From 67f8512ee13248284a7d08bd2a40468d8a5bf1c2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Sep 2019 20:14:30 -0400
Subject: [PATCH 0001/2348] test: repro #8150

---
 test/document.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 3a840be158a..184b160f8fc 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -7904,6 +7904,24 @@ describe('document', function() {
     });
   });
 
+  it('caster that converts to Number class works (gh-8150)', function() {
+    return co(function*() {
+        const mySchema = new Schema({
+          id: {
+            type: Number,
+            set: value => new Number(value.valueOf())
+          }
+        });
+      
+        const MyModel = db.model('gh8150', mySchema);
+      
+        yield MyModel.create({ id: 12345 });
+      
+        const doc = yield MyModel.findOne({ id: 12345 });
+        assert.ok(doc);
+    });
+  });
+
   it('handles objectids and decimals with strict: false (gh-7973)', function() {
     const testSchema = Schema({}, { strict: false });
     const Test = db.model('gh7973', testSchema);

From b4a3a280d2adbfa4ff8192d4cd23805a85c0dc2e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Sep 2019 20:14:38 -0400
Subject: [PATCH 0002/2348] fix: handle queries with setter that converts value
 to Number instance

Fix #8150
---
 lib/cast/number.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/cast/number.js b/lib/cast/number.js
index abc22f65cb9..18d2eebe6fd 100644
--- a/lib/cast/number.js
+++ b/lib/cast/number.js
@@ -29,7 +29,7 @@ module.exports = function castNumber(val) {
 
   assert.ok(!isNaN(val));
   if (val instanceof Number) {
-    return val;
+    return val.valueOf();
   }
   if (typeof val === 'number') {
     return val;
@@ -38,7 +38,7 @@ module.exports = function castNumber(val) {
     return Number(val.valueOf());
   }
   if (val.toString && !Array.isArray(val) && val.toString() == Number(val)) {
-    return new Number(val);
+    return Number(val);
   }
 
   assert.ok(false);

From 879599cb81cbbaa04b0aa04ee0de0c7118826860 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Sep 2019 20:15:22 -0400
Subject: [PATCH 0003/2348] chore: now working on 5.7.2

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 1eef07c8813..a363e9ab393 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.1",
+  "version": "5.7.2-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b05331b94ad551ea762f8d3474b72894b0835b13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Sep 2019 21:57:24 -0700
Subject: [PATCH 0004/2348] fix: use $wrapCallback when using promises

Fix mongoosejs/mongoose-async-hooks#6
---
 lib/model.js | 88 ++++++++++++++--------------------------------------
 lib/query.js |  8 ++---
 2 files changed, 26 insertions(+), 70 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index a1a96ebf6b8..1faabfc7a44 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -441,10 +441,6 @@ Model.prototype.save = function(options, fn) {
     options = undefined;
   }
 
-  if (fn) {
-    fn = this.constructor.$wrapCallback(fn);
-  }
-
   options = new SaveOptions(options);
   if (options.hasOwnProperty('session')) {
     this.$session(options.session);
@@ -452,7 +448,7 @@ Model.prototype.save = function(options, fn) {
 
   this.$__.$versionError = generateVersionError(this, this.modifiedPaths());
 
-  return utils.promiseOrCallback(fn, cb => {
+  return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
     if (parallelSave) {
       this.$__handleReject(parallelSave);
       return cb(parallelSave);
@@ -471,7 +467,7 @@ Model.prototype.save = function(options, fn) {
       }
       cb(null, this);
     });
-  }, this.constructor.events);
+  }), this.constructor.events);
 };
 
 /*!
@@ -892,13 +888,9 @@ Model.prototype.remove = function remove(options, fn) {
     this.$session(options.session);
   }
 
-  if (fn) {
-    fn = this.constructor.$wrapCallback(fn);
-  }
-
-  return utils.promiseOrCallback(fn, cb => {
+  return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
     this.$__remove(options, cb);
-  }, this.constructor.events);
+  }), this.constructor.events);
 };
 
 /**
@@ -929,13 +921,9 @@ Model.prototype.deleteOne = function deleteOne(options, fn) {
     options = {};
   }
 
-  if (fn) {
-    fn = this.constructor.$wrapCallback(fn);
-  }
-
-  return utils.promiseOrCallback(fn, cb => {
+  return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
     this.$__deleteOne(options, cb);
-  }, this.constructor.events);
+  }), this.constructor.events);
 };
 
 /*!
@@ -1272,16 +1260,12 @@ Model.createCollection = function createCollection(options, callback) {
     options = null;
   }
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
-
   const schemaCollation = get(this, 'schema.options.collation', null);
   if (schemaCollation != null) {
     options = Object.assign({ collation: schemaCollation }, options);
   }
 
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
       if (error) {
         return cb(error);
@@ -1289,7 +1273,7 @@ Model.createCollection = function createCollection(options, callback) {
       this.collection = this.db.collection(this.collection.collectionName, options);
       cb(null, this.collection);
     }));
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -1318,8 +1302,6 @@ Model.createCollection = function createCollection(options, callback) {
 Model.syncIndexes = function syncIndexes(options, callback) {
   _checkContext(this, 'syncIndexes');
 
-  callback = this.$wrapCallback(callback);
-
   const dropNonSchemaIndexes = (cb) => {
     this.listIndexes((err, indexes) => {
       if (err != null) {
@@ -1371,7 +1353,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
     });
   };
 
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     this.createCollection(err => {
       if (err) {
         return cb(err);
@@ -1388,7 +1370,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
         });
       });
     });
-  }, this.events);
+  }), this.events);
 };
 
 /*!
@@ -1442,20 +1424,18 @@ function isIndexEqual(model, schemaIndex, dbIndex) {
 Model.listIndexes = function init(callback) {
   _checkContext(this, 'listIndexes');
 
-  callback = this.$wrapCallback(callback);
-
   const _listIndexes = cb => {
     this.collection.listIndexes().toArray(cb);
   };
 
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     // Buffering
     if (this.collection.buffer) {
       this.collection.addQueue(_listIndexes, [cb]);
     } else {
       _listIndexes(cb);
     }
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -1495,18 +1475,14 @@ Model.ensureIndexes = function ensureIndexes(options, callback) {
     options = null;
   }
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
-
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     _ensureIndexes(this, options || {}, error => {
       if (error) {
         return cb(error);
       }
       cb(null);
     });
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -3017,11 +2993,7 @@ Model.create = function create(doc, options, callback) {
     }
   }
 
-  if (cb) {
-    cb = this.$wrapCallback(cb);
-  }
-
-  return utils.promiseOrCallback(cb, cb => {
+  return utils.promiseOrCallback(cb, this.$wrapCallback(cb => {
     if (args.length === 0) {
       return cb(null);
     }
@@ -3093,7 +3065,7 @@ Model.create = function create(doc, options, callback) {
         }
       });
     });
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -3412,14 +3384,11 @@ Model.bulkWrite = function(ops, options, callback) {
     callback = options;
     options = null;
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
   options = options || {};
 
   const validations = ops.map(op => castBulkWrite(this, op, options));
 
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     each(validations, (fn, cb) => fn(cb), error => {
       if (error) {
         return cb(error);
@@ -3433,7 +3402,7 @@ Model.bulkWrite = function(ops, options, callback) {
         cb(null, res);
       });
     });
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -3782,10 +3751,7 @@ function _update(model, op, conditions, doc, options, callback) {
 Model.mapReduce = function mapReduce(o, callback) {
   _checkContext(this, 'mapReduce');
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     if (!Model.mapReduce.schema) {
       const opts = {noId: true, noVirtualId: true, strict: false};
       Model.mapReduce.schema = new Schema({}, opts);
@@ -3822,7 +3788,7 @@ Model.mapReduce = function mapReduce(o, callback) {
 
       cb(null, res);
     });
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -3933,11 +3899,8 @@ Model.geoSearch = function(conditions, options, callback) {
     callback = options;
     options = {};
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
 
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     let error;
     if (conditions === undefined || !utils.isObject(conditions)) {
       error = new MongooseError('Must pass conditions to geoSearch');
@@ -3982,7 +3945,7 @@ Model.geoSearch = function(conditions, options, callback) {
         res.results[i].init(temp, {}, init);
       }
     });
-  }, this.events);
+  }), this.events);
 };
 
 /**
@@ -4062,9 +4025,6 @@ Model.populate = function(docs, paths, callback) {
   _checkContext(this, 'populate');
 
   const _this = this;
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
 
   // normalized paths
   paths = utils.populate(paths);
@@ -4072,9 +4032,9 @@ Model.populate = function(docs, paths, callback) {
   // data that should persist across subPopulate calls
   const cache = {};
 
-  return utils.promiseOrCallback(callback, cb => {
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     _populate(_this, docs, paths, cache, cb);
-  }, this.events);
+  }), this.events);
 };
 
 /*!
diff --git a/lib/query.js b/lib/query.js
index 89a27f3166e..9446e9ab660 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4293,11 +4293,7 @@ Query.prototype.exec = function exec(op, callback) {
     this.op = op;
   }
 
-  if (callback != null) {
-    callback = this.model.$wrapCallback(callback);
-  }
-
-  return utils.promiseOrCallback(callback, (cb) => {
+  return utils.promiseOrCallback(callback, this.model.$wrapCallback((cb) => {
     if (!_this.op) {
       cb();
       return;
@@ -4321,7 +4317,7 @@ Query.prototype.exec = function exec(op, callback) {
         });
       });
     });
-  }, this.model.events);
+  }), this.model.events);
 };
 
 /*!

From f98634e405df11cd6f5ce335ca83ad44333233c3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Sep 2019 22:08:16 -0700
Subject: [PATCH 0005/2348] style: fix lint

---
 test/document.test.js | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 184b160f8fc..6d35c5335a1 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -7906,19 +7906,19 @@ describe('document', function() {
 
   it('caster that converts to Number class works (gh-8150)', function() {
     return co(function*() {
-        const mySchema = new Schema({
-          id: {
-            type: Number,
-            set: value => new Number(value.valueOf())
-          }
-        });
-      
-        const MyModel = db.model('gh8150', mySchema);
-      
-        yield MyModel.create({ id: 12345 });
-      
-        const doc = yield MyModel.findOne({ id: 12345 });
-        assert.ok(doc);
+      const mySchema = new Schema({
+        id: {
+          type: Number,
+          set: value => new Number(value.valueOf())
+        }
+      });
+
+      const MyModel = db.model('gh8150', mySchema);
+
+      yield MyModel.create({ id: 12345 });
+
+      const doc = yield MyModel.findOne({ id: 12345 });
+      assert.ok(doc);
     });
   });
 

From 335193ba1a3b8d27892d8e158025e68ff6583a84 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Sep 2019 10:22:40 -0700
Subject: [PATCH 0006/2348] test: fix tests re: #8129

---
 lib/model.js | 98 +++++++++++++++++++++++++---------------------------
 lib/query.js |  2 ++
 2 files changed, 50 insertions(+), 50 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 1faabfc7a44..f5e4500cebc 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -448,6 +448,8 @@ Model.prototype.save = function(options, fn) {
 
   this.$__.$versionError = generateVersionError(this, this.modifiedPaths());
 
+  fn = this.constructor.$handleCallbackError(fn);
+
   return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
     if (parallelSave) {
       this.$__handleReject(parallelSave);
@@ -888,6 +890,8 @@ Model.prototype.remove = function remove(options, fn) {
     this.$session(options.session);
   }
 
+  fn = this.constructor.$handleCallbackError(fn);
+
   return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
     this.$__remove(options, cb);
   }), this.constructor.events);
@@ -921,6 +925,8 @@ Model.prototype.deleteOne = function deleteOne(options, fn) {
     options = {};
   }
 
+  fn = this.constructor.$handleCallbackError(fn);
+
   return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
     this.$__deleteOne(options, cb);
   }), this.constructor.events);
@@ -1265,6 +1271,8 @@ Model.createCollection = function createCollection(options, callback) {
     options = Object.assign({ collation: schemaCollation }, options);
   }
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
       if (error) {
@@ -1353,6 +1361,8 @@ Model.syncIndexes = function syncIndexes(options, callback) {
     });
   };
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     this.createCollection(err => {
       if (err) {
@@ -1428,6 +1438,8 @@ Model.listIndexes = function init(callback) {
     this.collection.listIndexes().toArray(cb);
   };
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     // Buffering
     if (this.collection.buffer) {
@@ -1475,6 +1487,8 @@ Model.ensureIndexes = function ensureIndexes(options, callback) {
     options = null;
   }
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     _ensureIndexes(this, options || {}, error => {
       if (error) {
@@ -1822,7 +1836,7 @@ Model.remove = function remove(conditions, callback) {
   // get the mongodb collection object
   const mq = new this.Query({}, {}, this, this.collection);
 
-  callback = this.$wrapCallback(callback);
+  callback = this.$handleCallbackError(callback);
 
   return mq.remove(conditions, callback);
 };
@@ -1863,9 +1877,7 @@ Model.deleteOne = function deleteOne(conditions, options, callback) {
   const mq = new this.Query(conditions, {}, this, this.collection);
   mq.setOptions(options);
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return mq.deleteOne(callback);
 };
@@ -1906,9 +1918,7 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
   const mq = new this.Query(conditions, {}, this, this.collection);
   mq.setOptions(options);
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return mq.deleteMany(callback);
 };
@@ -1984,9 +1994,7 @@ Model.find = function find(conditions, projection, options, callback) {
     mq.select(this.schema.options.discriminatorKey);
   }
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return mq.find(conditions, callback);
 };
@@ -2048,9 +2056,7 @@ Model.findById = function findById(id, projection, options, callback) {
     id = null;
   }
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return this.findOne({_id: id}, projection, options, callback);
 };
@@ -2124,9 +2130,7 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
     mq.select(this.schema.options.discriminatorKey);
   }
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return mq.findOne(conditions, callback);
 };
@@ -2152,7 +2156,7 @@ Model.estimatedDocumentCount = function estimatedDocumentCount(options, callback
 
   const mq = new this.Query({}, {}, this, this.collection);
 
-  callback = this.$wrapCallback(callback);
+  callback = this.$handleCallbackError(callback);
 
   return mq.estimatedDocumentCount(options, callback);
 };
@@ -2196,7 +2200,7 @@ Model.countDocuments = function countDocuments(conditions, callback) {
 
   const mq = new this.Query({}, {}, this, this.collection);
 
-  callback = this.$wrapCallback(callback);
+  callback = this.$handleCallbackError(callback);
 
   return mq.countDocuments(conditions, callback);
 };
@@ -2232,9 +2236,7 @@ Model.count = function count(conditions, callback) {
 
   const mq = new this.Query({}, {}, this, this.collection);
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return mq.count(conditions, callback);
 };
@@ -2272,9 +2274,7 @@ Model.distinct = function distinct(field, conditions, callback) {
     callback = conditions;
     conditions = {};
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return mq.distinct(field, conditions, callback);
 };
@@ -2424,9 +2424,7 @@ Model.findOneAndUpdate = function(conditions, update, options, callback) {
     update = conditions;
     conditions = undefined;
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   let fields;
   if (options) {
@@ -2548,9 +2546,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
 Model.findByIdAndUpdate = function(id, update, options, callback) {
   _checkContext(this, 'findByIdAndUpdate');
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
   if (arguments.length === 1) {
     if (typeof id === 'function') {
       const msg = 'Model.findByIdAndUpdate(): First argument must not be a function.\n\n'
@@ -2646,9 +2642,7 @@ Model.findOneAndDelete = function(conditions, options, callback) {
     callback = options;
     options = undefined;
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   let fields;
   if (options) {
@@ -2690,9 +2684,7 @@ Model.findByIdAndDelete = function(id, options, callback) {
         + '  ' + this.modelName + '.findByIdAndDelete()\n';
     throw new TypeError(msg);
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return this.findOneAndDelete({_id: id}, options, callback);
 };
@@ -2763,9 +2755,7 @@ Model.findOneAndReplace = function(filter, replacement, options, callback) {
     replacement = void 0;
     options = void 0;
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   let fields;
   if (options) {
@@ -2849,9 +2839,7 @@ Model.findOneAndRemove = function(conditions, options, callback) {
     callback = options;
     options = undefined;
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   let fields;
   if (options) {
@@ -2910,9 +2898,7 @@ Model.findByIdAndRemove = function(id, options, callback) {
         + '  ' + this.modelName + '.findByIdAndRemove()\n';
     throw new TypeError(msg);
   }
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
 
   return this.findOneAndRemove({_id: id}, options, callback);
 };
@@ -3193,6 +3179,7 @@ Model.$__insertMany = function(arr, options, callback) {
     options = null;
   }
   if (callback) {
+    callback = this.$handleCallbackError(callback);
     callback = this.$wrapCallback(callback);
   }
   callback = callback || utils.noop;
@@ -3388,6 +3375,8 @@ Model.bulkWrite = function(ops, options, callback) {
 
   const validations = ops.map(op => castBulkWrite(this, op, options));
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     each(validations, (fn, cb) => fn(cb), error => {
       if (error) {
@@ -3654,7 +3643,7 @@ Model.replaceOne = function replaceOne(conditions, doc, options, callback) {
 function _update(model, op, conditions, doc, options, callback) {
   const mq = new model.Query({}, {}, model, model.collection);
   if (callback) {
-    callback = model.$wrapCallback(callback);
+    callback = this.$handleCallbackError(callback);
   }
   // gh-2406
   // make local deep copy of conditions
@@ -3751,6 +3740,8 @@ function _update(model, op, conditions, doc, options, callback) {
 Model.mapReduce = function mapReduce(o, callback) {
   _checkContext(this, 'mapReduce');
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     if (!Model.mapReduce.schema) {
       const opts = {noId: true, noVirtualId: true, strict: false};
@@ -3856,9 +3847,8 @@ Model.aggregate = function aggregate(pipeline, callback) {
     return aggregate;
   }
 
-  if (callback) {
-    callback = this.$wrapCallback(callback);
-  }
+  callback = this.$handleCallbackError(callback);
+  callback = this.$wrapCallback(callback);
 
   aggregate.exec(callback);
   return aggregate;
@@ -3900,6 +3890,8 @@ Model.geoSearch = function(conditions, options, callback) {
     options = {};
   }
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     let error;
     if (conditions === undefined || !utils.isObject(conditions)) {
@@ -4032,6 +4024,8 @@ Model.populate = function(docs, paths, callback) {
   // data that should persist across subPopulate calls
   const cache = {};
 
+  callback = this.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
     _populate(_this, docs, paths, cache, cb);
   }), this.events);
@@ -4585,7 +4579,7 @@ Model.__subclass = function subclass(conn, schema, collection) {
   return Model;
 };
 
-Model.$wrapCallback = function(callback) {
+Model.$handleCallbackError = function(callback) {
   if (callback == null) {
     return callback;
   }
@@ -4602,6 +4596,10 @@ Model.$wrapCallback = function(callback) {
   };
 };
 
+Model.$wrapCallback = function(callback) {
+  return callback;
+};
+
 /**
  * Helper for console.log. Given a model named 'MyModel', returns the string
  * `'Model { MyModel }'`.
diff --git a/lib/query.js b/lib/query.js
index 9446e9ab660..b0961a2f97c 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4293,6 +4293,8 @@ Query.prototype.exec = function exec(op, callback) {
     this.op = op;
   }
 
+  callback = this.model.$handleCallbackError(callback);
+
   return utils.promiseOrCallback(callback, this.model.$wrapCallback((cb) => {
     if (!_this.op) {
       cb();

From 97c8114b69cc1047ff454312dc8d334948eb94d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Sep 2019 11:13:39 -0700
Subject: [PATCH 0007/2348] test(model): fix tests

---
 lib/model.js | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index f5e4500cebc..ca41fc0e99b 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3642,9 +3642,8 @@ Model.replaceOne = function replaceOne(conditions, doc, options, callback) {
 
 function _update(model, op, conditions, doc, options, callback) {
   const mq = new model.Query({}, {}, model, model.collection);
-  if (callback) {
-    callback = this.$handleCallbackError(callback);
-  }
+
+  callback = model.$handleCallbackError(callback);
   // gh-2406
   // make local deep copy of conditions
   if (conditions instanceof Document) {

From d9c91cb89eb7ed1b436d8c72ac983368f9e50660 Mon Sep 17 00:00:00 2001
From: Anaet Hossain Rezve <anaethoss@gmail.com>
Date: Wed, 18 Sep 2019 15:49:57 +0600
Subject: [PATCH 0008/2348] fix example typo for Schema.prototype.plugin()

---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 249d8acee25..b3670d97b8b 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1378,7 +1378,7 @@ Schema.prototype.post = function(name) {
  *
  *     const s = new Schema({ name: String });
  *     s.plugin(schema => console.log(schema.path('name').path));
- *     mongoose.model('Test', schema); // Prints 'name'
+ *     mongoose.model('Test', s); // Prints 'name'
  *
  * @param {Function} plugin callback
  * @param {Object} [opts]

From 9c9a70d5cac3f4d09eacefae72ba670034aeef80 Mon Sep 17 00:00:00 2001
From: Rob Riddle <rob@bitpay.com>
Date: Fri, 20 Sep 2019 12:48:09 -0400
Subject: [PATCH 0009/2348] Fix all indexes not being created for a model if
 one fails

---
 lib/model.js               | 10 +++++++--
 test/model.indexes.test.js | 42 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index ca41fc0e99b..bdd3f9f4fbb 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1527,6 +1527,7 @@ Model.createIndexes = function createIndexes(options, callback) {
 
 function _ensureIndexes(model, options, callback) {
   const indexes = model.schema.indexes();
+  let indexError;
 
   options = options || {};
 
@@ -1534,7 +1535,7 @@ function _ensureIndexes(model, options, callback) {
     if (err && !model.$caught) {
       model.emit('error', err);
     }
-    model.emit('index', err);
+    model.emit('index', err || indexError);
     callback && callback(err);
   };
 
@@ -1606,7 +1607,12 @@ function _ensureIndexes(model, options, callback) {
     model.collection[methodName](indexFields, indexOptions, utils.tick(function(err, name) {
       indexSingleDone(err, indexFields, indexOptions, name);
       if (err) {
-        return done(err);
+        if (!indexError) {
+          indexError = err;
+        }
+        if (!model.$caught) {
+          model.emit('error', err);
+        }
       }
       create();
     }));
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 15891a4b2a9..7d358231257 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -282,6 +282,48 @@ describe('model', function() {
       });
     });
 
+    it('when one index creation errors', function(done) {
+      const User = new Schema({
+        name: { type: String },
+        secondValue: { type: Boolean }
+      });
+      User.index({ name: 1 });
+
+      const User2 = new Schema({
+        name: {type: String, index: true, unique: true},
+        secondValue: {type: Boolean, index: true}
+      });
+      User2.index({ name: 1 }, { unique: true });
+      User2.index({ secondValue: 1 });
+
+      const collectionName = 'deepindexedmodel' + random();
+      const UserModel = db.model('SingleIndexedModel', User, collectionName);
+      const UserModel2 = db.model('DuplicateIndexedModel', User2, collectionName);
+      let assertions = 0;
+
+      UserModel2.on('index', function() {
+        UserModel2.collection.getIndexes(function(err, indexes) {
+          assert.ifError(err);
+
+          function iter(index) {
+            if (index[0] === 'name') {
+              assertions++;
+            }
+            if (index[0] === 'secondValue') {
+              assertions++;
+            }
+          }
+
+          for (const i in indexes) {
+            indexes[i].forEach(iter);
+          }
+
+          assert.equal(assertions, 2);
+          done();
+        });
+      });
+    });
+
     describe('auto creation', function() {
       it('can be disabled', function(done) {
         const schema = new Schema({name: {type: String, index: true}});

From 276cc4a0e2a2dc1d0a100fae45e6b809940c6f54 Mon Sep 17 00:00:00 2001
From: Rob Riddle <rob@bitpay.com>
Date: Fri, 20 Sep 2019 13:07:49 -0400
Subject: [PATCH 0010/2348] Fix lint issue, clean up test a bit more, add
 comments

---
 test/model.indexes.test.js | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 7d358231257..8e99b1f6afa 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -283,21 +283,23 @@ describe('model', function() {
     });
 
     it('when one index creation errors', function(done) {
-      const User = new Schema({
-        name: { type: String },
-        secondValue: { type: Boolean }
-      });
+      const userSchema = {
+        name: {type: String},
+        secondValue: {type: Boolean}
+      };
+
+      const User = new Schema(userSchema);
       User.index({ name: 1 });
 
-      const User2 = new Schema({
-        name: {type: String, index: true, unique: true},
-        secondValue: {type: Boolean, index: true}
-      });
+      const User2 = new Schema(userSchema);
       User2.index({ name: 1 }, { unique: true });
       User2.index({ secondValue: 1 });
 
       const collectionName = 'deepindexedmodel' + random();
-      const UserModel = db.model('SingleIndexedModel', User, collectionName);
+      // Create model with first schema to initialize indexes
+      db.model('SingleIndexedModel', User, collectionName);
+
+      // Create model with second schema in same collection to add new indexes
       const UserModel2 = db.model('DuplicateIndexedModel', User2, collectionName);
       let assertions = 0;
 

From 80cba3f3f4483df1285a3675910b7db7271daa55 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Sep 2019 15:00:25 -0700
Subject: [PATCH 0011/2348] fix(mongoose): support `mongoose.set('autoIndex',
 false)`

Fix #8158
---
 lib/index.js |  1 +
 lib/model.js |  5 ++---
 lib/utils.js | 16 ++++++++++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index c76914492c7..ad89dffc536 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -158,6 +158,7 @@ Mongoose.prototype.driver = require('./driver');
  * - 'strict': true by default, may be `false`, `true`, or `'throw'`. Sets the default strict mode for schemas.
  * - 'selectPopulatedPaths': true by default. Set to false to opt out of Mongoose adding all fields that you `populate()` to your `select()`. The schema-level option `selectPopulatedPaths` overwrites this one.
  * - 'maxTimeMS': If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query
+ * - 'autoIndex': true by default. Set to false to disable automatic index creation for all models associated with this Mongoose instance.
  *
  * @param {String} key
  * @param {String|Function|Boolean} value
diff --git a/lib/model.js b/lib/model.js
index ca41fc0e99b..238b3d73225 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1184,9 +1184,8 @@ Model.init = function init(callback) {
   }
 
   const Promise = PromiseProvider.get();
-  const autoIndex = this.schema.options.autoIndex == null ?
-    this.db.config.autoIndex :
-    this.schema.options.autoIndex;
+  const autoIndex = utils.getOption('autoIndex',
+    this.schema.options, this.db.config, this.db.base.options);
   const autoCreate = this.schema.options.autoCreate == null ?
     this.db.config.autoCreate :
     this.schema.options.autoCreate;
diff --git a/lib/utils.js b/lib/utils.js
index 7a34b4376fc..846b68ee0ac 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -1072,6 +1072,22 @@ exports.each = function(arr, fn) {
   }
 };
 
+/*!
+ * ignore
+ */
+
+exports.getOption = function(name) {
+  const sources = Array.prototype.slice.call(arguments, 1);
+
+  for (const source of sources) {
+    if (source[name] != null) {
+      return source[name];
+    }
+  }
+
+  return null;
+};
+
 /*!
  * ignore
  */

From 1e0cc7a347797f10297496b396eeac807e02f385 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Sep 2019 10:44:32 -0700
Subject: [PATCH 0012/2348] test(query): repro #8159

---
 test/query.toconstructor.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/query.toconstructor.test.js b/test/query.toconstructor.test.js
index dc291a4036a..164456ef785 100644
--- a/test/query.toconstructor.test.js
+++ b/test/query.toconstructor.test.js
@@ -214,5 +214,14 @@ describe('Query:', function() {
         assert.strictEqual(called, 1);
       });
     });
+
+    it('works with entries-style sort() syntax (gh-8159)', function() {
+      const Model = mongoose.model('Test', Schema({ name: String }));
+
+      const query = Model.find().sort([['name', 1]]);
+      const Query = query.toConstructor();
+      const q = new Query();
+      assert.deepEqual(q.options.sort, [['name', 1]]);
+    });
   });
 });

From 952120a7c072cb02bc1d97c7691f1ceadf2c881e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Sep 2019 10:44:51 -0700
Subject: [PATCH 0013/2348] fix(query): handle `toConstructor()` with
 entries-style sort syntax

Fix #8159
---
 lib/query.js | 10 +++++++++-
 package.json |  2 +-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index b0961a2f97c..714ceb38c54 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -188,7 +188,15 @@ Query.prototype.toConstructor = function toConstructor() {
 
   p.options = {};
 
-  p.setOptions(this.options);
+  // Need to handle `sort()` separately because entries-style `sort()` syntax
+  // `sort([['prop1', 1]])` confuses mquery into losing the outer nested array.
+  // See gh-8159
+  const options = Object.assign({}, this.options);
+  if (options.sort != null) {
+    p.sort(options.sort);
+    delete options.sort;
+  }
+  p.setOptions(options);
 
   p.op = this.op;
   p._conditions = utils.clone(this._conditions);
diff --git a/package.json b/package.json
index a363e9ab393..8c25adcdf03 100644
--- a/package.json
+++ b/package.json
@@ -25,7 +25,7 @@
     "mongodb": "3.3.2",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
-    "mquery": "3.2.1",
+    "mquery": "3.2.2",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.1.2",

From d8cc819e3e3106cc607298dfccfdabdd05ff1cb3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Sep 2019 20:48:41 -0700
Subject: [PATCH 0014/2348] test: fix tests

---
 test/query.toconstructor.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/query.toconstructor.test.js b/test/query.toconstructor.test.js
index 164456ef785..5c933043780 100644
--- a/test/query.toconstructor.test.js
+++ b/test/query.toconstructor.test.js
@@ -216,7 +216,7 @@ describe('Query:', function() {
     });
 
     it('works with entries-style sort() syntax (gh-8159)', function() {
-      const Model = mongoose.model('Test', Schema({ name: String }));
+      const Model = mongoose.model('gh8159', Schema({ name: String }));
 
       const query = Model.find().sort([['name', 1]]);
       const Query = query.toConstructor();

From e2d191aa8a07c965123e3ab7d1c989c9c1f917d3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Sep 2019 21:06:31 -0700
Subject: [PATCH 0015/2348] fix(discriminator): support `tiedValue` parameter
 for embedded discriminators analagous to top-level discriminators

Fix #8164
---
 lib/schema/SingleNestedPath.js   |  4 ++--
 lib/schema/documentarray.js      |  4 ++--
 test/model.discriminator.test.js | 40 ++++++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 4 deletions(-)

diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 9a2142f4159..3862529619c 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -283,8 +283,8 @@ SingleNestedPath.prototype.doValidateSync = function(value, scope, options) {
  * @api public
  */
 
-SingleNestedPath.prototype.discriminator = function(name, schema) {
-  discriminator(this.caster, name, schema);
+SingleNestedPath.prototype.discriminator = function(name, schema, tiedValue) {
+  discriminator(this.caster, name, schema, tiedValue);
 
   this.caster.discriminators[name] = _createConstructor(schema, this.caster);
 
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index cce9026d776..9229676f77d 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -126,12 +126,12 @@ function _createConstructor(schema, options, baseClass) {
  * Ignore
  */
 
-DocumentArray.prototype.discriminator = function(name, schema) {
+DocumentArray.prototype.discriminator = function(name, schema, tiedValue) {
   if (typeof name === 'function') {
     name = utils.getFunctionName(name);
   }
 
-  schema = discriminator(this.casterConstructor, name, schema);
+  schema = discriminator(this.casterConstructor, name, schema, tiedValue);
 
   const EmbeddedDocument = _createConstructor(schema, null, this.casterConstructor);
   EmbeddedDocument.baseCasterConstructor = this.casterConstructor;
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 0155ad61824..eb25e0a3939 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1080,6 +1080,46 @@ describe('model', function() {
         catch(done);
     });
 
+    it('embedded with single nested subdocs and tied value (gh-8164)', function() {
+      const eventSchema = new Schema({ message: String },
+        { discriminatorKey: 'kind', _id: false });
+
+        const trackSchema = new Schema({ event: eventSchema });
+      trackSchema.path('event').discriminator('Clicked', new Schema({
+        element: String
+      }, { _id: false }), 'click');
+      trackSchema.path('event').discriminator('Purchased', new Schema({
+        product: String
+      }, { _id: false }), 'purchase');
+
+      const MyModel = db.model('gh8164', trackSchema);
+      const doc1 = {
+        event: {
+          kind: 'click',
+          element: 'Amazon Link'
+        }
+      };
+      const doc2 = {
+        event: {
+          kind: 'purchase',
+          product: 'Professional AngularJS'
+        }
+      };
+      return MyModel.create([doc1, doc2]).
+        then(function(docs) {
+          const doc1 = docs[0];
+          const doc2 = docs[1];
+
+          assert.equal(doc1.event.kind, 'click');
+          assert.equal(doc1.event.element, 'Amazon Link');
+          assert.ok(!doc1.event.product);
+
+          assert.equal(doc2.event.kind, 'purchase');
+          assert.equal(doc2.event.product, 'Professional AngularJS');
+          assert.ok(!doc2.event.element);
+        });
+    });
+
     it('Embedded discriminators in nested doc arrays (gh-6202)', function() {
       const eventSchema = new Schema({ message: String }, {
         discriminatorKey: 'kind',

From bdfce8fd4556554914b714e8c79c29467e39a329 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Sep 2019 10:19:00 -0700
Subject: [PATCH 0016/2348] docs: add mongoosejs-cli to readme

Fix #8142
---
 README.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/README.md b/README.md
index aa88c246e4d..11839b87e3e 100644
--- a/README.md
+++ b/README.md
@@ -319,6 +319,10 @@ and [acquit](https://github.com/vkarpov15/acquit).
 - [mongodb-memory-server](https://www.npmjs.com/package/mongodb-memory-server)
 - [mongodb-topology-manager](https://www.npmjs.com/package/mongodb-topology-manager)
 
+#### Unofficial CLIs
+
+- [mongoosejs-cli](https://www.npmjs.com/package/mongoosejs-cli)
+
 #### Data Seeding
 
 - [dookie](https://www.npmjs.com/package/dookie)

From fb0bd0d956594f0c65ddf21f35b15c1371024545 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Sep 2019 12:38:32 -0700
Subject: [PATCH 0017/2348] fix(populate): avoid converting mixed paths into
 arrays if populating an object path under `Mixed`

Fix #8157
---
 lib/helpers/populate/getModelsMapForPopulate.js | 10 +++++++---
 test/types.map.test.js                          |  8 ++++++--
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 62fc180c6bc..abb68b7bf09 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -166,7 +166,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         ret = localFieldPath.applyGetters(localFieldValue, hydratedDoc);
       }
     } else {
-      ret = convertTo_id(utils.getValue(localField, doc));
+      ret = convertTo_id(utils.getValue(localField, doc), schema);
     }
 
     const id = String(utils.getValue(foreignField, doc));
@@ -377,7 +377,7 @@ function handleRefFunction(ref, doc) {
  * @return {Array|Document|Any}
  */
 
-function convertTo_id(val) {
+function convertTo_id(val, schema) {
   if (val != null && val.$__ != null) return val._id;
 
   if (Array.isArray(val)) {
@@ -395,7 +395,11 @@ function convertTo_id(val) {
 
   // `populate('map')` may be an object if populating on a doc that hasn't
   // been hydrated yet
-  if (val != null && val.constructor.name === 'Object') {
+  if (val != null &&
+      val.constructor.name === 'Object' &&
+      // The intent here is we should only flatten the object if we expect
+      // to get a Map in the end. Avoid doing this for mixed types.
+      (schema == null || schema[schemaMixedSymbol] == null)) {
     const ret = [];
     for (const key of Object.keys(val)) {
       ret.push(val[key]);
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 19cc6762a61..34a72d3ee04 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -371,7 +371,7 @@ describe('Map', function() {
       });
     });
 
-    it('avoid populating as map if populate on obj (gh-6460)', function() {
+    it('avoid populating as map if populate on obj (gh-6460) (gh-8157)', function() {
       const UserSchema = new mongoose.Schema({
         apiKeys: {}
       });
@@ -387,8 +387,12 @@ describe('Map', function() {
 
         const doc = yield User.create({ apiKeys: { github: key._id, twitter: key2._id } });
 
-        const populated = yield User.findById(doc).populate('apiKeys');
+        const populated = yield User.findById(doc).populate({
+          path: 'apiKeys',
+          skipInvalidIds: true
+        });
         assert.ok(!(populated.apiKeys instanceof Map));
+        assert.ok(!Array.isArray(populated.apiKeys));
       });
     });
 

From dea0b95b63ad7123f8340d9e77bc975d88dee354 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Sep 2019 13:27:38 -0700
Subject: [PATCH 0018/2348] chore: release 5.7.2

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index cc70229dad5..7d6340c1e57 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.7.2 / 2019-09-23
+==================
+ * fix(mongoose): support `mongoose.set('autoIndex', false)` #8158
+ * fix(discriminator): support `tiedValue` parameter for embedded discriminators analagous to top-level discriminators #8164
+ * fix(query): handle `toConstructor()` with entries-style sort syntax #8159
+ * fix(populate): avoid converting mixed paths into arrays if populating an object path under `Mixed` #8157
+ * fix: use $wrapCallback when using promises for mongoose-async-hooks
+ * fix: handle queries with setter that converts value to Number instance #8150
+ * docs: add mongoosejs-cli to readme #8142
+ * docs: fix example typo for Schema.prototype.plugin() #8175 [anaethoss](https://github.com/anaethoss)
+
 5.7.1 / 2019-09-13
 ==================
  * fix(query): fix TypeError when calling `findOneAndUpdate()` with `runValidators` #8151 [fernandolguevara](https://github.com/fernandolguevara)
diff --git a/package.json b/package.json
index 8c25adcdf03..8f5da217aac 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.2-pre",
+  "version": "5.7.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 1a01713b93ffb8b079b7bd5553eff450482eb6aa Mon Sep 17 00:00:00 2001
From: "Dr. Sergey Pogodin" <dr.pogodin@gmail.com>
Date: Mon, 23 Sep 2019 23:46:21 +0200
Subject: [PATCH 0019/2348] [#8093] Fixes performance of update validator, and
 flatten function logic

Before this commit the `flatten(..)` function failed to deliver what it
promised. Namely, it entered into Mixed paths of objects.

Update validator, on its side, did not pass the casted doc schema into
`flatten(..)`. If the casted doc contained a large Mixed field, all its
paths were added into the list of updated paths. They were lated ignored
by now removed check for schemaPath type, but performance was already
hurt.

This commit makes sure that inner sub-paths of Mixed paths are not
included into the array of paths at all, thus no further checks of that
are necessary, and the performance is restored.

Fixes #8093
---
 lib/helpers/common.js           |  7 +++----
 lib/helpers/updateValidators.js | 10 ++--------
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/lib/helpers/common.js b/lib/helpers/common.js
index b0a8f1b1fd9..b5fb9e4738d 100644
--- a/lib/helpers/common.js
+++ b/lib/helpers/common.js
@@ -33,15 +33,14 @@ function flatten(update, path, options, schema) {
     result[path + key] = val;
 
     // Avoid going into mixed paths if schema is specified
-    if (schema != null && schema.paths[path + key] != null && schema.paths[path + key].instance === 'Mixed') {
-      continue;
-    }
+    const keySchema = schema && schema.path(path + key);
+    if (keySchema && keySchema.instance === 'Mixed') continue;
 
     if (shouldFlatten(val)) {
       if (options && options.skipArrays && Array.isArray(val)) {
         continue;
       }
-      const flat = flatten(val, path + key, options);
+      const flat = flatten(val, path + key, options, schema);
       for (const k in flat) {
         result[k] = flat[k];
       }
diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index 6b68ebc9b99..92c088ee6b1 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -54,7 +54,7 @@ module.exports = function(query, schema, castedDoc, options, callback) {
         continue;
       }
       modifiedPaths(castedDoc[keys[i]], '', modified);
-      const flat = flatten(castedDoc[keys[i]]);
+      const flat = flatten(castedDoc[keys[i]], null, null, schema);
       const paths = Object.keys(flat);
       const numPaths = paths.length;
       for (let j = 0; j < numPaths; ++j) {
@@ -79,7 +79,7 @@ module.exports = function(query, schema, castedDoc, options, callback) {
 
   if (!hasDollarUpdate) {
     modifiedPaths(castedDoc, '', modified);
-    updatedValues = flatten(castedDoc);
+    updatedValues = flatten(castedDoc, null, null, schema);
     updatedKeys = Object.keys(updatedValues);
   }
 
@@ -97,12 +97,6 @@ module.exports = function(query, schema, castedDoc, options, callback) {
       return;
     }
 
-    // gh-4305: `_getSchema()` will report all sub-fields of a 'Mixed' path
-    // as 'Mixed', so avoid double validating them.
-    if (schemaPath instanceof Mixed && schemaPath.path !== updates[i]) {
-      return;
-    }
-
     if (v && Array.isArray(v.$in)) {
       v.$in.forEach((v, i) => {
         validatorsToExecute.push(function(callback) {

From c76e06267fcc9f99b561f6962783fa7d2e2b8cf5 Mon Sep 17 00:00:00 2001
From: "Dr. Sergey Pogodin" <dr.pogodin@gmail.com>
Date: Tue, 24 Sep 2019 00:23:17 +0200
Subject: [PATCH 0020/2348] Fixes the previous commit

---
 lib/helpers/common.js           | 2 +-
 lib/helpers/updateValidators.js | 1 -
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/helpers/common.js b/lib/helpers/common.js
index b5fb9e4738d..3398f4cbe09 100644
--- a/lib/helpers/common.js
+++ b/lib/helpers/common.js
@@ -33,7 +33,7 @@ function flatten(update, path, options, schema) {
     result[path + key] = val;
 
     // Avoid going into mixed paths if schema is specified
-    const keySchema = schema && schema.path(path + key);
+    const keySchema = schema && schema.path && schema.path(path + key);
     if (keySchema && keySchema.instance === 'Mixed') continue;
 
     if (shouldFlatten(val)) {
diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index 92c088ee6b1..199ef0677f7 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -4,7 +4,6 @@
  * Module dependencies.
  */
 
-const Mixed = require('../schema/mixed');
 const ValidationError = require('../error/validation');
 const cleanPositionalOperators = require('./schema/cleanPositionalOperators');
 const flatten = require('./common').flatten;

From 1db5982cabce907f4cee3c056e890767803abe27 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Sep 2019 15:32:35 -0700
Subject: [PATCH 0021/2348] docs: link to map blog post

---
 docs/schematypes.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index cd21dbfbfea..ade9a47a067 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -450,7 +450,7 @@ block content
 
     _New in Mongoose 5.1.0_
 
-    A `MongooseMap` is a subclass of the built-in [`Map` class](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map).
+    A `MongooseMap` is a subclass of [JavaScript's `Map` class](http://thecodebarbarian.com/the-80-20-guide-to-maps-in-javascript.html).
     In these docs, we'll use the terms 'map' and `MongooseMap` interchangeably.
     In Mongoose, maps are how you create a nested document with arbitrary keys.
 

From b42d0f5d5642fcdbb0e96581a60b3e93ef28b192 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 24 Sep 2019 15:38:40 -0700
Subject: [PATCH 0022/2348] test(populate): repro #8173 #6488

---
 test/model.populate.test.js | 46 +++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index b137d5b8b16..8256c2600c6 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8627,4 +8627,50 @@ describe('model: populate:', function() {
       assert.equal(team.developers[2].ticketCount, 0);
     });
   });
+
+  it('handles virtual populate underneath embedded discriminator nested path (gh-6488) (gh-8173)', function() {
+    return co(function*() {
+      const UserModel = db.model('gh6488_User', Schema({
+        employeeId: Number,
+        name: String
+      }));
+
+      const eventSchema = Schema({ message: String }, { discriminatorKey: 'kind' });
+      const batchSchema = Schema({ nested: { events: [eventSchema] } });
+
+      const nestedLayerSchema = Schema({ users: [ Number ] });
+      nestedLayerSchema.virtual('users_$', {
+        ref: 'gh6488_User',
+        localField: 'users',
+        foreignField: 'employeeId'
+      });
+
+      const docArray = batchSchema.path('nested.events');
+      const Clicked = docArray.
+        discriminator('gh6488_Clicked', Schema({ nestedLayer: nestedLayerSchema }));
+      const Purchased = docArray.
+        discriminator('gh6488_Purchased', Schema({ purchased: String }));
+
+      const Batch = db.model('gh6488', batchSchema);
+
+      yield UserModel.create({ employeeId: 1, name: 'test' });
+      yield Batch.create({
+        nested: {
+          events: [
+            { kind: 'gh6488_Clicked', nestedLayer: { users: [1] } },
+            { kind: 'gh6488_Purchased', purchased: 'test' }
+          ]
+        }
+      });
+
+      let res = yield Batch.findOne().
+        populate('nested.events.nestedLayer.users_$');
+      assert.equal(res.nested.events[0].nestedLayer.users_$.length, 1);
+      assert.equal(res.nested.events[0].nestedLayer.users_$[0].name, 'test');
+
+      res = res.toObject({ virtuals: true });
+      assert.equal(res.nested.events[0].nestedLayer.users_$.length, 1);
+      assert.equal(res.nested.events[0].nestedLayer.users_$[0].name, 'test');
+    });
+  });
 });

From 0a33412b1544fdf7f69b52cf65ea2785ff86d0f6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 24 Sep 2019 15:40:24 -0700
Subject: [PATCH 0023/2348] fix(populate): handle virtual populate of an
 embedded discriminator nested path

Fix #8173
Re: #6488
---
 .../populate/getModelsMapForPopulate.js       | 11 +++++----
 lib/helpers/populate/getVirtual.js            | 23 +++++++++++--------
 test/helpers/populate.getVirtual.test.js      | 18 +++++++--------
 test/model.populate.test.js                   |  8 +++----
 4 files changed, 32 insertions(+), 28 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index abb68b7bf09..990f8a64c32 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -78,12 +78,14 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       }
     }
 
-    const virtual = getVirtual(model.schema, options.path);
+    const _virtualRes = getVirtual(model.schema, options.path);
+    const virtual = _virtualRes == null ? null : _virtualRes.virtual;
+
     let localField;
     let count = false;
     if (virtual && virtual.options) {
-      const virtualPrefix = virtual.$nestedSchemaPath ?
-        virtual.$nestedSchemaPath + '.' : '';
+      const virtualPrefix = _virtualRes.nestedSchemaPath ?
+        _virtualRes.nestedSchemaPath + '.' : '';
       if (typeof virtual.options.localField === 'function') {
         localField = virtualPrefix + virtual.options.localField.call(doc, doc);
       } else {
@@ -312,7 +314,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       } else {
         schemaForCurrentDoc = schema;
       }
-      const virtual = getVirtual(modelForCurrentDoc.schema, options.path);
+      const _virtualRes = getVirtual(modelForCurrentDoc.schema, options.path);
+      const virtual = _virtualRes == null ? null : _virtualRes.virtual;
 
       let ref;
       let refPath;
diff --git a/lib/helpers/populate/getVirtual.js b/lib/helpers/populate/getVirtual.js
index dd2644d5150..056828b85ec 100644
--- a/lib/helpers/populate/getVirtual.js
+++ b/lib/helpers/populate/getVirtual.js
@@ -8,7 +8,7 @@ module.exports = getVirtual;
 
 function getVirtual(schema, name) {
   if (schema.virtuals[name]) {
-    return schema.virtuals[name];
+    return { virtual: schema.virtuals[name], path: void 0 };
   }
   const parts = name.split('.');
   let cur = '';
@@ -17,8 +17,7 @@ function getVirtual(schema, name) {
     cur += (cur.length > 0 ? '.' : '') + parts[i];
     if (schema.virtuals[cur]) {
       if (i === parts.length - 1) {
-        schema.virtuals[cur].$nestedSchemaPath = nestedSchemaPath;
-        return schema.virtuals[cur];
+        return { virtual: schema.virtuals[cur], path: nestedSchemaPath };
       }
       continue;
     }
@@ -33,20 +32,24 @@ function getVirtual(schema, name) {
 
       if (schema.virtuals[rest]) {
         if (i === parts.length - 2) {
-          schema.virtuals[rest].$nestedSchemaPath =
-            [nestedSchemaPath, cur].filter(v => !!v).join('.');
-          return schema.virtuals[rest];
+          return {
+            virtual: schema.virtuals[rest],
+            nestedSchemaPath:[nestedSchemaPath, cur].filter(v => !!v).join('.')
+          };
         }
         continue;
       }
 
       if (i + 1 < parts.length && schema.discriminators) {
         for (const key of Object.keys(schema.discriminators)) {
-          const _virtual = getVirtual(schema.discriminators[key], rest);
-          if (_virtual != null) {
-            _virtual.$nestedSchemaPath = [nestedSchemaPath, cur].
+          const res = getVirtual(schema.discriminators[key], rest);
+          if (res != null) {
+            const _path = [nestedSchemaPath, cur, res.nestedSchemaPath].
               filter(v => !!v).join('.');
-            return _virtual;
+            return {
+              virtual: res.virtual,
+              nestedSchemaPath: _path
+            };
           }
         }
       }
diff --git a/test/helpers/populate.getVirtual.test.js b/test/helpers/populate.getVirtual.test.js
index 16facb7e8a9..6f6f2d75454 100644
--- a/test/helpers/populate.getVirtual.test.js
+++ b/test/helpers/populate.getVirtual.test.js
@@ -39,7 +39,7 @@ describe('getVirtual', function() {
       product: { type: String }
     }));
 
-    assert.equal(getVirtual(batchSchema, 'nested.events.users_$').options.ref,
+    assert.equal(getVirtual(batchSchema, 'nested.events.users_$').virtual.options.ref,
       'Users');
 
     done();
@@ -80,8 +80,8 @@ describe('getVirtual', function() {
     // Second embedded discriminator
     docArray.discriminator('Purchased', new Schema({ product: String }));
 
-    const virtual = getVirtual(batchSchema, 'nested.events.nestedLayer.users_$');
-    assert.equal(virtual.options.ref, 'Users');
+    const res = getVirtual(batchSchema, 'nested.events.nestedLayer.users_$');
+    assert.equal(res.virtual.options.ref, 'Users');
 
     done();
   });
@@ -106,13 +106,13 @@ describe('getVirtual', function() {
 
     docArray.discriminator('Clicked', clickedSchema);
 
-    let virtual = getVirtual(batchSchema, 'events.users_$');
-    assert.equal(virtual.options.ref, 'Users');
-    assert.equal(virtual.$nestedSchemaPath, 'events');
+    let res = getVirtual(batchSchema, 'events.users_$');
+    assert.equal(res.virtual.options.ref, 'Users');
+    assert.equal(res.nestedSchemaPath, 'events');
 
-    virtual = getVirtual(batchSchema, 'events.users_$');
-    assert.equal(virtual.options.ref, 'Users');
-    assert.equal(virtual.$nestedSchemaPath, 'events');
+    res = getVirtual(batchSchema, 'events.users_$');
+    assert.equal(res.virtual.options.ref, 'Users');
+    assert.equal(res.nestedSchemaPath, 'events');
 
     done();
   });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 8256c2600c6..51c95ca766c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8628,7 +8628,7 @@ describe('model: populate:', function() {
     });
   });
 
-  it('handles virtual populate underneath embedded discriminator nested path (gh-6488) (gh-8173)', function() {
+  it('handles virtual populate of an embedded discriminator nested path (gh-6488) (gh-8173)', function() {
     return co(function*() {
       const UserModel = db.model('gh6488_User', Schema({
         employeeId: Number,
@@ -8646,10 +8646,8 @@ describe('model: populate:', function() {
       });
 
       const docArray = batchSchema.path('nested.events');
-      const Clicked = docArray.
-        discriminator('gh6488_Clicked', Schema({ nestedLayer: nestedLayerSchema }));
-      const Purchased = docArray.
-        discriminator('gh6488_Purchased', Schema({ purchased: String }));
+      docArray.discriminator('gh6488_Clicked', Schema({ nestedLayer: nestedLayerSchema }));
+      docArray.discriminator('gh6488_Purchased', Schema({ purchased: String }));
 
       const Batch = db.model('gh6488', batchSchema);
 

From 8c98a3aa59382ae78a0bfb363ce6ddc3a703b6e0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 24 Sep 2019 15:43:10 -0700
Subject: [PATCH 0024/2348] chore: now working on 5.7.3

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 8f5da217aac..f64ca2add80 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.2",
+  "version": "5.7.3-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9d455adde47de4ee5514a71786aa1b3c51380fb2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 25 Sep 2019 11:11:07 -0700
Subject: [PATCH 0025/2348] test(update): repro #8166

---
 test/model.update.test.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 612a25f2513..dc2da0c1c5b 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3315,4 +3315,37 @@ describe('model: updateOne: ', function() {
       assert.equal(doc.test, 'after');
     });
   });
+
+  it('allow $pull with non-existent schema field (gh-8166)', function() {
+    const Model = db.model('gh8166', Schema({
+      name: String,
+      arr: [{
+        status: String,
+        values: [{ text: String }]
+      }]
+    }));
+
+    return co(function*() {
+      yield Model.collection.insertMany([
+        {
+          name: 'a',
+          arr: [{ values: [{ text: '123' }] }]
+        },
+        {
+          name: 'b',
+          arr: [{ values: [{ text: '123', coords: 'test' }] }]
+        }
+      ]);
+
+      yield Model.updateMany({}, {
+        $pull: { arr: { 'values.0.coords': { $exists: false } } }
+      });
+
+      const docs = yield Model.find().sort({ name: 1 });
+      assert.equal(docs[0].name, 'a');
+      assert.equal(docs[0].arr.length, 0);
+      assert.equal(docs[1].name, 'b');
+      assert.equal(docs[1].arr.length, 1);
+    });
+  });
 });
\ No newline at end of file

From c371500730310ad3a0362c91f16da2e1f91de8a8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 25 Sep 2019 11:11:16 -0700
Subject: [PATCH 0026/2348] fix(update): cast right hand side of `$pull` as a
 query instead of an update for document arrays

Fix #8166
---
 lib/helpers/query/castUpdate.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 8b289af7af1..37a53b5a7e6 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -4,6 +4,7 @@ const CastError = require('../../error/cast');
 const StrictModeError = require('../../error/strict');
 const ValidationError = require('../../error/validation');
 const castNumber = require('../../cast/number');
+const cast = require('../../cast');
 const getEmbeddedDiscriminatorPath = require('./getEmbeddedDiscriminatorPath');
 const handleImmutable = require('./handleImmutable');
 const utils = require('../../utils');
@@ -139,6 +140,17 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
     key = keys[i];
     val = obj[key];
 
+    // `$pull` is special because we need to cast the RHS as a query, not as
+    // an update.
+    if (op === '$pull') {
+      schematype = schema._getSchema(prefix + key);
+      if (schematype != null && schematype.schema != null) {
+        obj[key] = cast(schematype.schema, obj[key], options, context);
+        hasKeys = true;
+        continue;
+      }
+    }
+
     if (val && val.constructor.name === 'Object') {
       // watch for embedded doc schemas
       schematype = schema._getSchema(prefix + key);

From c5b235537e8888fd04d2928ec550f206b53fd8e7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 26 Sep 2019 22:50:24 -0700
Subject: [PATCH 0027/2348] docs(promises): add note about queries being
 thenable

Fix #8110
---
 test/docs/promises.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/docs/promises.test.js b/test/docs/promises.test.js
index d798b14bd84..3a96d2ca835 100644
--- a/test/docs/promises.test.js
+++ b/test/docs/promises.test.js
@@ -84,6 +84,21 @@ describe('promises docs', function () {
     });
   });
 
+  /**
+   * Although queries are not promises, queries are [thenables](https://promisesaplus.com/#terminology).
+   * That means they have a `.then()` function, so you can use queries as promises with either
+   * promise chaining or [async await](https://asyncawait.net)
+   */
+  it('Queries are thenable', function (done) {
+    Band.findOne({name: "Guns N' Roses"}).then(function(doc) {
+      // use doc
+      // acquit:ignore:start
+      assert.ok(!doc);
+      done();
+      // acquit:ignore:end
+    });
+  });
+  
   /**
    * If you're an advanced user, you may want to plug in your own promise
    * library like [bluebird](https://www.npmjs.com/package/bluebird). Just set

From e60db1b1d928a6da02f08e4890356087826e7c24 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@Valeris-MacBook-Air.local>
Date: Fri, 27 Sep 2019 14:29:12 -0700
Subject: [PATCH 0028/2348] refactor(cursor): remove dependency on
 async.times()

Re: #8073
Re: #5502
---
 lib/helpers/cursor/eachAsync.js | 28 ++++++++++++++++++++++------
 test/aggregate.test.js          |  4 ++--
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 5ab0f5785fc..5e6207c7687 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -38,10 +38,11 @@ module.exports = function eachAsync(next, fn, options, callback) {
   const iterate = function(callback) {
     let drained = false;
     const nextQueue = async.queue(function(task, cb) {
-      if (drained) return cb();
+      if (drained) {
+        return cb();
+      }
       next(function(err, doc) {
         if (err) return cb(err);
-        if (!doc) drained = true;
         cb(null, doc);
       });
     }, 1);
@@ -49,7 +50,13 @@ module.exports = function eachAsync(next, fn, options, callback) {
     const getAndRun = function(cb) {
       nextQueue.push({}, function(err, doc) {
         if (err) return cb(err);
-        if (!doc) return cb();
+        if (drained) {
+          return;
+        }
+        if (doc == null) {
+          drained = true;
+          return callback(null);
+        }
         handleNextResult(doc, function(err) {
           if (err) return cb(err);
           // Make sure to clear the stack re: gh-4697
@@ -60,9 +67,18 @@ module.exports = function eachAsync(next, fn, options, callback) {
       });
     };
 
-    async.times(parallel, function(n, cb) {
-      getAndRun(cb);
-    }, callback);
+    let error = null;
+    for (let i = 0; i < parallel; ++i) {
+      getAndRun(err => {
+        if (error != null) {
+          return;
+        }
+        if (err != null) {
+          error = err;
+          return callback(err);
+        }
+      });
+    }
   };
 
   return utils.promiseOrCallback(callback, cb => {
diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 5854659b4c4..c20d7cd374c 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -1288,10 +1288,10 @@ describe('aggregate: ', function() {
         return MyModel.aggregate([{ $sort: { name: 1 } }]).
           cursor().
           exec().
-          eachAsync(checkDoc, { parallel: 2}).then(function() {
+          eachAsync(checkDoc, { parallel: 2 }).then(function() {
             assert.ok(Date.now() - startedAt[1] >= 100);
             assert.equal(startedAt.length, 2);
-            assert.ok(startedAt[1] - startedAt[0] < 50);
+            assert.ok(startedAt[1] - startedAt[0] < 50, `${startedAt[1] - startedAt[0]}`);
             assert.deepEqual(names.sort(), expectedNames);
             done();
           });

From 36472927155dc861a57e878c2b6e68f91a522dda Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Sep 2019 08:25:37 -0700
Subject: [PATCH 0029/2348] refactor(cursor): remove async.queue() from
 eachAsync() re: #8073 #5502

---
 lib/helpers/cursor/eachAsync.js | 42 ++++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 11 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 5e6207c7687..a343c01b0aa 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -4,7 +4,6 @@
  * Module dependencies.
  */
 
-const async = require('async');
 const utils = require('../../utils');
 
 /**
@@ -37,18 +36,9 @@ module.exports = function eachAsync(next, fn, options, callback) {
 
   const iterate = function(callback) {
     let drained = false;
-    const nextQueue = async.queue(function(task, cb) {
-      if (drained) {
-        return cb();
-      }
-      next(function(err, doc) {
-        if (err) return cb(err);
-        cb(null, doc);
-      });
-    }, 1);
 
     const getAndRun = function(cb) {
-      nextQueue.push({}, function(err, doc) {
+      _next(function(err, doc) {
         if (err) return cb(err);
         if (drained) {
           return;
@@ -81,7 +71,37 @@ module.exports = function eachAsync(next, fn, options, callback) {
     }
   };
 
+  const _nextQueue = [];
   return utils.promiseOrCallback(callback, cb => {
     iterate(cb);
   });
+
+  // `next()` can only execute one at a time, so make sure we always execute
+  // `next()` in series, while still allowing multiple `fn()` instances to run
+  // in parallel.
+  function _next(cb) {
+    if (_nextQueue.length === 0) {
+      return next(_step(cb));
+    }
+    _nextQueue.push(cb);
+  }
+
+  function _step(cb) {
+    return function(err, doc) {
+      if (err != null) {
+        return cb(err);
+      }
+      cb(null, doc);
+
+      if (doc == null) {
+        return;
+      }
+
+      setTimeout(() => {
+        if (_nextQueue.length > 0) {
+          next(_step(_nextQueue.unshift()));
+        }
+      }, 0);
+    };
+  }
 };

From 9bb4b034ab4ca3cb03cf18eb888bdd308612d2d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Sep 2019 08:26:02 -0700
Subject: [PATCH 0030/2348] refactor: remove async as a prod dependency

Fix #8073
---
 package.json                              |  2 +-
 test/docs/discriminators.test.js          | 33 ++--------
 test/model.discriminator.querying.test.js | 78 ++++++++---------------
 test/model.populate.test.js               | 68 ++++++--------------
 test/query.test.js                        |  1 +
 5 files changed, 52 insertions(+), 130 deletions(-)

diff --git a/package.json b/package.json
index f64ca2add80..8cb9ed2b848 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,6 @@
   ],
   "license": "MIT",
   "dependencies": {
-    "async": "2.6.2",
     "bson": "~1.1.1",
     "kareem": "2.3.1",
     "mongodb": "3.3.2",
@@ -37,6 +36,7 @@
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
+    "async": "2.6.2",
     "babel-loader": "7.1.4",
     "babel-preset-es2015": "6.24.1",
     "benchmark": "2.1.4",
diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index 76fb52b394a..829976dbf82 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -1,7 +1,6 @@
 'use strict';
 
 var assert = require('assert');
-var async = require('async');
 var mongoose = require('../../');
 
 var Schema = mongoose.Schema;
@@ -90,21 +89,14 @@ describe('discriminator docs', function () {
       });
     };
 
-    async.map([event1, event2, event3], save, function (error) {
-      // acquit:ignore:start
-      assert.ifError(error);
-      // acquit:ignore:end
-
-      Event.countDocuments({}, function (error, count) {
-        // acquit:ignore:start
-        assert.ifError(error);
-        // acquit:ignore:end
+    Promise.all([event1.save(), event2.save(), event3.save()]).
+      then(() => Event.countDocuments()).
+      then(count => {
         assert.equal(count, 3);
         // acquit:ignore:start
         done();
         // acquit:ignore:end
       });
-    });
   });
 
   /**
@@ -138,21 +130,9 @@ describe('discriminator docs', function () {
     var event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
     var event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
 
-    var save = function (doc, callback) {
-      doc.save(function (error, doc) {
-        callback(error, doc);
-      });
-    };
-
-    async.map([event1, event2, event3], save, function (error) {
-      // acquit:ignore:start
-      assert.ifError(error);
-      // acquit:ignore:end
-
-      ClickedLinkEvent.find({}, function (error, docs) {
-        // acquit:ignore:start
-        assert.ifError(error);
-        // acquit:ignore:end
+    Promise.all([event1.save(), event2.save(), event3.save()]).
+      then(() => ClickedLinkEvent.find({})).
+      then(docs => {
         assert.equal(docs.length, 1);
         assert.equal(docs[0]._id.toString(), event2._id.toString());
         assert.equal(docs[0].url, 'google.com');
@@ -160,7 +140,6 @@ describe('discriminator docs', function () {
         done();
         // acquit:ignore:end
       });
-    });
   });
 
   /**
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 4d780f69499..9132cc78e04 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -10,8 +10,6 @@ const Schema = mongoose.Schema;
 const assert = require('assert');
 const random = require('../lib/utils').random;
 const util = require('util');
-const async = require('async');
-
 
 /**
  * Setup
@@ -47,21 +45,10 @@ describe('model', function() {
       SecretEvent = BaseEvent.discriminator('model-discriminator-querying-secret', SecretEventSchema);
     });
 
-    afterEach(function(done) {
-      async.series(
-        [
-          function removeBaseEvent(next) {
-            BaseEvent.deleteMany({}, next);
-          },
-          function removeImpressionEvent(next) {
-            ImpressionEvent.deleteMany({}, next);
-          },
-          function removeConversionEvent(next) {
-            ConversionEvent.deleteMany({}, next);
-          }
-        ],
-        done
-      );
+    afterEach(function() {
+      return BaseEvent.deleteMany({}).
+        then(() => ImpressionEvent.deleteMany({})).
+        then(() => ConversionEvent.deleteMany({}));
     });
 
     after(function(done) {
@@ -86,7 +73,7 @@ describe('model', function() {
         ContainerModel = db.model('container-event-model', ContainerSchema);
       });
 
-      it('into non-discriminated arrays works', function(done) {
+      it('into non-discriminated arrays works', function() {
         const c = new ContainerModel({
           title: 'events-group-1'
         });
@@ -95,32 +82,25 @@ describe('model', function() {
         const d3 = new DiscCustomEvent();
         c.events.push(d1);
         c.events.push(d2);
-        async.series(
-          [
-            function(next) { d1.save(next); },
-            function(next) { d2.save(next); },
-            function(next) { d3.save(next); },
-            function(next) { c.save(next); },
-            function(next) {
-              ContainerModel.findOne({}).populate('events').exec(function(err, doc) {
-                assert.ifError(err);
-                assert.ok(doc.events && doc.events.length);
-                assert.equal(doc.events.length, 2);
-                doc.events.push(d3);
-                let hasDisc = false;
-                const discKey = DiscCustomEvent.schema.discriminatorMapping.key;
-                doc.events.forEach(function(subDoc) {
-                  if (discKey in subDoc) {
-                    hasDisc = true;
-                  }
-                });
-                assert.ok(hasDisc);
-                next();
-              });
-            }
-          ],
-          done
-        );
+
+        return d1.save().
+          then(() => d2.save()).
+          then(() => d3.save()).
+          then(() => c.save()).
+          then(() => ContainerModel.findOne({}).populate('events')).
+          then(doc => {
+            assert.ok(doc.events && doc.events.length);
+            assert.equal(doc.events.length, 2);
+            doc.events.push(d3);
+            let hasDisc = false;
+            const discKey = DiscCustomEvent.schema.discriminatorMapping.key;
+            doc.events.forEach(function(subDoc) {
+              if (discKey in subDoc) {
+                hasDisc = true;
+              }
+            });
+            assert.ok(hasDisc);
+          });
       });
     });
 
@@ -879,18 +859,12 @@ describe('model', function() {
     describe('aggregate', function() {
       let impressionEvent, conversionEvent, ignoredImpressionEvent;
 
-      beforeEach(function(done) {
+      beforeEach(function() {
         impressionEvent = new ImpressionEvent({name: 'Test Event'});
         conversionEvent = new ConversionEvent({name: 'Test Event', revenue: 10});
         ignoredImpressionEvent = new ImpressionEvent({name: 'Ignored Event'});
 
-        async.forEach(
-          [impressionEvent, conversionEvent, ignoredImpressionEvent],
-          function(doc, cb) {
-            doc.save(cb);
-          },
-          done
-        );
+        return Promise.all([impressionEvent, conversionEvent, ignoredImpressionEvent].map(d => d.save()));
       });
 
       describe('using "RootModel#aggregate"', function() {
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 51c95ca766c..efc2be74ba2 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -5,7 +5,6 @@
  */
 
 const assert = require('assert');
-const async = require('async');
 const co = require('co');
 const start = require('./common');
 const utils = require('../lib/utils');
@@ -4035,7 +4034,7 @@ describe('model: populate:', function() {
       });
     });
 
-    it('out-of-order discriminators (gh-4073)', function(done) {
+    it('out-of-order discriminators (gh-4073)', function() {
       const UserSchema = new Schema({
         name: String
       });
@@ -4094,54 +4093,23 @@ describe('model: populate:', function() {
       const be2 = new BlogPostEvent({ blogpost: b2 });
       const be3 = new BlogPostEvent({ blogpost: b3 });
 
-      async.series(
-        [
-          u1.save.bind(u1),
-          u2.save.bind(u2),
-          u3.save.bind(u3),
-
-          c1.save.bind(c1),
-          c2.save.bind(c2),
-          c3.save.bind(c3),
-
-          b1.save.bind(b1),
-          b2.save.bind(b2),
-          b3.save.bind(b3),
-
-          ce1.save.bind(ce1),
-          ue1.save.bind(ue1),
-          be1.save.bind(be1),
-
-          ce2.save.bind(ce2),
-          ue2.save.bind(ue2),
-          be2.save.bind(be2),
-
-          ce3.save.bind(ce3),
-          ue3.save.bind(ue3),
-          be3.save.bind(be3),
-
-          function(next) {
-            Event.
-              find({}).
-              populate('user comment blogpost').
-              exec(function(err, docs) {
-                docs.forEach(function(doc) {
-                  if (doc.__t === 'User4073') {
-                    assert.ok(doc.user.name.indexOf('user') !== -1);
-                  } else if (doc.__t === 'Comment4073') {
-                    assert.ok(doc.comment.content.indexOf('comment') !== -1);
-                  } else if (doc.__t === 'BlogPost4073') {
-                    assert.ok(doc.blogpost.title.indexOf('blog post') !== -1);
-                  } else {
-                    assert.ok(false);
-                  }
-                });
-                next();
-              });
-          }
-        ],
-        done
-      );
+      const docs = [u1, u2, u3, c1, c2, c3, b1, b2, b3, ce1, ue1, be1, ce2, ue2, be2, ce3, ue3, be3];
+
+      return Promise.all(docs.map(d => d.save())).
+        then(() => Event.find({}).populate('user comment blogpost')).
+        then(docs => {
+          docs.forEach(function(doc) {
+            if (doc.__t === 'User4073') {
+              assert.ok(doc.user.name.indexOf('user') !== -1);
+            } else if (doc.__t === 'Comment4073') {
+              assert.ok(doc.comment.content.indexOf('comment') !== -1);
+            } else if (doc.__t === 'BlogPost4073') {
+              assert.ok(doc.blogpost.title.indexOf('blog post') !== -1);
+            } else {
+              assert.ok(false);
+            }
+          });
+        });
     });
 
     it('dynref bug (gh-4104)', function(done) {
diff --git a/test/query.test.js b/test/query.test.js
index aef6940df9c..ce8a2ae4cf4 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -2408,6 +2408,7 @@ describe('Query', function() {
       });
 
       it('throw on sync exceptions in callbacks (gh-6178)', function(done) {
+        const async = require('async');
         const schema = new Schema({});
         const Test = db.model('gh6178', schema);
 

From 6c91deafb9ca9176c84b3bf38654768c1a9dc3b2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Sep 2019 08:55:51 -0700
Subject: [PATCH 0031/2348] style: fix lint

---
 test/query.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/query.test.js b/test/query.test.js
index ce8a2ae4cf4..5a67e45eb32 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -7,7 +7,6 @@
 const start = require('./common');
 const Query = require('../lib/query');
 const assert = require('assert');
-const async = require('async');
 const co = require('co');
 const random = require('../lib/utils').random;
 

From 98b5a73243f831c7c69b889ab86d2e50d4f17a6d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Sep 2019 21:51:31 -0700
Subject: [PATCH 0032/2348] fix: make CoreMongooseArray#includes() handle
 `fromIndex` parameter

Fix #8203
---
 lib/types/core_array.js  | 12 ++++++++----
 test/types.array.test.js |  2 ++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 324e04ad245..b298acf4664 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -457,8 +457,9 @@ class CoreMongooseArray extends Array {
    * @memberOf MongooseArray
    */
 
-  includes(obj) {
-    return this.indexOf(obj) !== -1;
+  includes(obj, fromIndex) {
+    const ret = this.indexOf(obj, fromIndex);
+    return ret !== -1;
   }
 
   /**
@@ -471,11 +472,14 @@ class CoreMongooseArray extends Array {
    * @memberOf MongooseArray
    */
 
-  indexOf(obj) {
+  indexOf(obj, fromIndex) {
     if (obj instanceof ObjectId) {
       obj = obj.toString();
     }
-    for (let i = 0, len = this.length; i < len; ++i) {
+
+    fromIndex = fromIndex == null ? 0 : fromIndex;
+    const len = this.length;
+    for (let i = fromIndex; i < len; ++i) {
       if (obj == this[i]) {
         return i;
       }
diff --git a/test/types.array.test.js b/test/types.array.test.js
index 85d5c49732d..449634dd3ae 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -162,6 +162,8 @@ describe('types array', function() {
               assert.equal(user.pets.includes(tobi.id), true);
               assert.equal(user.pets.includes(loki.id), true);
               assert.equal(user.pets.includes(jane.id), true);
+              assert.equal(user.pets.includes(tobi.id, 1), false);
+              assert.equal(user.pets.includes(loki.id, 1), true);
               done();
             });
           });

From 7fee719574d00d7831906420dfc12e631f585575 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Sep 2019 22:24:36 -0700
Subject: [PATCH 0033/2348] docs(documents): add overwriting section

Fix #8178
---
 docs/documents.pug | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/docs/documents.pug b/docs/documents.pug
index 0bff0166c44..b452fcce5ed 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -142,6 +142,28 @@ block content
 
     Read the [validation](./validation.html) guide for more details.
 
+    ### Overwriting
+
+    There are 2 different ways to overwrite a document (replacing all keys in the
+    document). One way is to use the
+    [`Document#overwrite()` function](/docs/api/document.html#document_Document-overwrite)
+    followed by `save()`.
+
+    ```javascript
+    const doc = await Person.findOne({ _id });
+
+    // Sets `name` and unsets all other properties
+    doc.overwrite({ name: 'Jean-Luc Picard' });
+    await doc.save();
+    ```
+
+    The other way is to use [`Model.replaceOne()`](/docs/api/model.html#model_Model.replaceOne).
+
+    ```javascript
+    // Sets `name` and unsets all other properties
+    await Person.replaceOne({ _id }, { name: 'Jean-Luc Picard' });
+    ```
+
     ### Next Up
 
     Now that we've covered Documents, let's take a look at

From 06112b061aa8a29b56fc92aae16797805700e417 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Sep 2019 12:22:40 -0700
Subject: [PATCH 0034/2348] docs(validation): remove deprecated `isAsync` from
 validation docs in favor of emphasizing promises

Fix #8184
---
 test/docs/validation.test.js | 40 +++++++-----------------------------
 1 file changed, 7 insertions(+), 33 deletions(-)

diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 60ace2f48c7..19f239d9e5c 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -222,16 +222,14 @@ describe('validation docs', function() {
   /**
    * Custom validators can also be asynchronous. If your validator function
    * returns a promise (like an `async` function), mongoose will wait for that
-   * promise to settle. If you prefer callbacks, set the `isAsync` option,
-   * and mongoose will pass a callback as the 2nd argument to your validator
-   * function.
+   * promise to settle. If the returned promise rejects, or fulfills with
+   * the value `false`, Mongoose will consider that a validation error.
    */
   it('Async Custom Validators', function(done) {
-    var userSchema = new Schema({
+    const userSchema = new Schema({
       name: {
         type: String,
-        // You can also make a validator async by returning a promise. If you
-        // return a promise, do **not** specify the `isAsync` option.
+        // You can also make a validator async by returning a promise.
         validate: () => Promise.reject(new Error('Oops!'))
       },
       email: {
@@ -243,42 +241,18 @@ describe('validation docs', function() {
           validator: () => Promise.resolve(false),
           message: 'Email validation failed'
         }
-      },
-      // Your async validator may use callbacks as an alternative to promises,
-      // but only if you specify `isAsync: true`.
-      phone: {
-        type: String,
-        validate: {
-          isAsync: true,
-          validator: function(v, cb) {
-            setTimeout(function() {
-              var phoneRegex = /\d{3}-\d{3}-\d{4}/;
-              var msg = v + ' is not a valid phone number!';
-              // First argument is a boolean, whether validator succeeded
-              // 2nd argument is an optional error message override
-              cb(phoneRegex.test(v), msg);
-            }, 5);
-          },
-          // Default error message, overridden by 2nd argument to `cb()` above
-          message: 'Default error message'
-        },
-        required: [true, 'User phone number required']
       }
     });
 
-    var User = db.model('User', userSchema);
-    var user = new User();
-    var error;
+    const User = db.model('User', userSchema);
+    const user = new User();
 
-    user.phone = '555.0123';
     user.email = 'test@test.co';
     user.name = 'test';
-    user.validate(function(error) {
+    user.validate().catch(error => {
       assert.ok(error);
       assert.equal(error.errors['name'].message, 'Oops!');
       assert.equal(error.errors['email'].message, 'Email validation failed');
-      assert.equal(error.errors['phone'].message,
-        '555.0123 is not a valid phone number!');
       // acquit:ignore:start
       done();
       // acquit:ignore:end

From 43b63ae8d18e49db3ddb56b4c843637339495a76 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Sep 2019 11:17:45 -0700
Subject: [PATCH 0035/2348] chore: release 5.7.3

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 7d6340c1e57..a7449fd590a 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.7.3 / 2019-09-30
+==================
+ * fix: make CoreMongooseArray#includes() handle `fromIndex` parameter #8203
+ * fix(update): cast right hand side of `$pull` as a query instead of an update for document arrays #8166
+ * fix(populate): handle virtual populate of an embedded discriminator nested path #8173
+ * docs(validation): remove deprecated `isAsync` from validation docs in favor of emphasizing promises #8184
+ * docs(documents): add overwriting section #8178
+ * docs(promises): add note about queries being thenable #8110
+ * perf: avoid update validators going into Mixed types #8192 [birdofpreyru](https://github.com/birdofpreyru)
+ * refactor: remove async as a prod dependency #8073
+
 5.7.2 / 2019-09-23
 ==================
  * fix(mongoose): support `mongoose.set('autoIndex', false)` #8158
diff --git a/package.json b/package.json
index 8cb9ed2b848..f78348999b5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.3-pre",
+  "version": "5.7.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 84619beadc5edb7f1ec9cc20b5b79c91d3b6366c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Oct 2019 12:39:29 -0700
Subject: [PATCH 0036/2348] test(document): repro #8201

---
 test/document.test.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 6d35c5335a1..2f829b712fe 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8081,4 +8081,37 @@ describe('document', function() {
     doc.init(data);
     require('util').inspect(doc.subdocs);
   });
+
+  it('set() merge option with single nested (gh-8201)', function() {
+    const AddressSchema = Schema({
+      street: { type: String, required: true },
+      city: { type: String, required: true }
+    });
+    const PersonSchema = Schema({
+      name: { type: String, required: true },
+      address: { type: AddressSchema, required: true }
+    });
+    const Person = db.model('gh8201', PersonSchema);
+
+    return co(function*() {
+      yield Person.create({
+        name: 'John Smith',
+        address: {
+          street: 'Real Street',
+          city: 'Somewhere'
+        }
+      });
+
+      const person = yield Person.findOne();
+      person.set({
+        name: 'John Smythe',
+        address: { street: 'Fake Street' } },
+        undefined,
+        { merge: true }
+      );
+
+      assert.equal(person.address.city, 'Somewhere');
+      yield person.save();
+    });
+  });
 });

From a2db9dbca5592fed08e7c016e7cfe34dcc5c4a32 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Oct 2019 12:39:43 -0700
Subject: [PATCH 0037/2348] fix(document): handle `Document#set()` merge option
 when setting underneath single nested schema

Fix #8201
---
 lib/document.js | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 413b0de35b7..0183ce47e51 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -856,7 +856,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
         this.schema.paths[pathName].options &&
         this.schema.paths[pathName].options.ref)) {
       this.$__.$setCalled.add(prefix + key);
-      this.$set(path[key], prefix + key, constructing);
+      this.$set(path[key], prefix + key, constructing, options);
     } else if (strict) {
       // Don't overwrite defaults with undefined keys (gh-3981)
       if (constructing && path[key] === void 0 &&
@@ -876,10 +876,10 @@ Document.prototype.$set = function $set(path, val, type, options) {
             path[key] instanceof Document) {
           p = p.toObject({ virtuals: false, transform: false });
         }
-        this.$set(prefix + key, p, constructing);
+        this.$set(prefix + key, p, constructing, options);
       } else if (pathtype === 'nested' && path[key] instanceof Document) {
         this.$set(prefix + key,
-          path[key].toObject({transform: false}), constructing);
+          path[key].toObject({transform: false}), constructing, options);
       } else if (strict === 'throw') {
         if (pathtype === 'nested') {
           throw new ObjectExpectedError(key, path[key]);
@@ -888,7 +888,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
         }
       }
     } else if (path[key] !== void 0) {
-      this.$set(prefix + key, path[key], constructing);
+      this.$set(prefix + key, path[key], constructing, options);
     }
   }
 
@@ -1034,6 +1034,18 @@ Document.prototype.$set = function $set(path, val, type, options) {
     return this;
   }
 
+  if (schema.$isSingleNested && val != null && merge) {
+    if (val instanceof Document) {
+      val = val.toObject({ virtuals: false, transform: false });
+    }
+    const keys = Object.keys(val);
+    for (const key of keys) {
+      this.$set(path + '.' + key, val[key], constructing, options);
+    }
+
+    return this;
+  }
+
   let shouldSet = true;
   try {
     // If the user is trying to set a ref path to a document with
@@ -1097,11 +1109,11 @@ Document.prototype.$set = function $set(path, val, type, options) {
       didPopulate = true;
     }
 
-    // If this path is underneath a single nested schema, we'll call the setter
-    // later in `$__set()` because we don't take `_doc` when we iterate through
-    // a single nested doc. That's to make sure we get the correct context.
-    // Otherwise we would double-call the setter, see gh-7196.
     if (this.schema.singleNestedPaths[path] == null) {
+      // If this path is underneath a single nested schema, we'll call the setter
+      // later in `$__set()` because we don't take `_doc` when we iterate through
+      // a single nested doc. That's to make sure we get the correct context.
+      // Otherwise we would double-call the setter, see gh-7196.
       val = schema.applySetters(val, this, false, priorVal);
     }
 

From f2ac6fbef54f3092f4953207ddeae36ee56a283d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Oct 2019 12:40:35 -0700
Subject: [PATCH 0038/2348] chore: now working on 5.7.4

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index f78348999b5..682feddea58 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.3",
+  "version": "5.7.4-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9a1d494141a482d2923ac7f2224b80886bc2b6e8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Oct 2019 12:42:20 -0700
Subject: [PATCH 0039/2348] style: fix lint

---
 test/document.test.js | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 2f829b712fe..1e32f7fe291 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8103,12 +8103,11 @@ describe('document', function() {
       });
 
       const person = yield Person.findOne();
-      person.set({
+      const obj = {
         name: 'John Smythe',
-        address: { street: 'Fake Street' } },
-        undefined,
-        { merge: true }
-      );
+        address: { street: 'Fake Street' }
+      };
+      person.set(obj, undefined, { merge: true });
 
       assert.equal(person.address.city, 'Somewhere');
       yield person.save();

From f8db7ce25626d75d06ceb56e012ff6839fce42c2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Oct 2019 19:24:59 -0700
Subject: [PATCH 0040/2348] test(populate): repro #8198

---
 test/model.populate.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index efc2be74ba2..699973d53ff 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8639,4 +8639,32 @@ describe('model: populate:', function() {
       assert.equal(res.nested.events[0].nestedLayer.users_$[0].name, 'test');
     });
   });
+
+  it('accessing populate virtual prop (gh-8198)', function() {
+    const FooSchema = new Schema({
+      name: String,
+      children: [{
+        barId: { type: Schema.Types.ObjectId, ref: 'gh8198_Bar' },
+        quantity: Number,
+      }]
+    });
+    FooSchema.virtual('children.bar', {
+      ref: 'gh8198_Bar',
+      localField: 'children.barId',
+      foreignField: '_id',
+      justOne: true
+    });
+    const BarSchema = Schema({ name: String });
+    const Foo = db.model('gh8198_FooSchema', FooSchema);
+    const Bar = db.model('gh8198_Bar', BarSchema);
+    return co(function*() {
+      const bar = yield Bar.create({ name: 'bar' });
+      const foo = yield Foo.create({
+        name: 'foo',
+        children: [{ barId: bar._id, quantity: 1 }]
+      });
+      const foo2 = yield Foo.findById(foo._id).populate('children.bar');
+      assert.equal(foo2.children[0].bar.name, 'bar');
+    });
+  });
 });

From dc0025b4a12e6042b83e13324de569ad3771b692 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Oct 2019 19:25:10 -0700
Subject: [PATCH 0041/2348] fix(populate): allow accessing populate virtual
 prop underneath array when virtual defined on top level

Fix #8198
Re: #8210
---
 lib/schema.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index b3670d97b8b..41fb876fd7e 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -10,6 +10,7 @@ const SchemaType = require('./schematype');
 const VirtualType = require('./virtualtype');
 const applyTimestampsToChildren = require('./helpers/update/applyTimestampsToChildren');
 const applyTimestampsToUpdate = require('./helpers/update/applyTimestampsToUpdate');
+const arrayParentSymbol = require('./helpers/symbols').arrayParentSymbol;
 const get = require('./helpers/get');
 const getIndexes = require('./helpers/schema/getIndexes');
 const handleTimestampOption = require('./helpers/schema/handleTimestampOption');
@@ -1724,6 +1725,22 @@ Schema.prototype.virtual = function(name, options) {
     return mem[part];
   }, this.tree);
 
+  // Workaround for gh-8198: if virtual is under document array, make a fake
+  // virtual. See gh-8210
+  let cur = parts[0];
+  for (let i = 0; i < parts.length - 1; ++i) {
+    if (this.paths[cur] != null && this.paths[cur].$isMongooseDocumentArray) {
+      const remnant = parts.slice(i + 1).join('.');
+      const v = this.paths[cur].schema.virtual(remnant);
+      v.get((v, virtual, doc) => {
+        const parent = doc.__parentArray[arrayParentSymbol];
+        const path = cur + '.' + doc.__index + '.' + remnant;
+        return parent.get(path);
+      });
+      break;
+    }
+  }
+
   return virtuals[name];
 };
 

From 294c191c20d3f3aaa3900a79b740427635fa0eaf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Oct 2019 11:15:15 -0700
Subject: [PATCH 0042/2348] refactor(schematype): add SchemaTypeOptions class
 re: #8012

---
 lib/options/SchemaTypeOptions.js | 148 +++++++++++++++++++++++++++++++
 lib/schema.js                    |   2 +
 lib/schematype.js                |  12 +--
 3 files changed, 157 insertions(+), 5 deletions(-)
 create mode 100644 lib/options/SchemaTypeOptions.js

diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
new file mode 100644
index 00000000000..97e6206cf17
--- /dev/null
+++ b/lib/options/SchemaTypeOptions.js
@@ -0,0 +1,148 @@
+'use strict';
+
+const utils = require('../utils');
+
+class SchemaTypeOptions {
+  constructor(obj) {
+    if (obj == null) {
+      return this;
+    }
+    Object.assign(this, utils.clone(obj));
+  }
+}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * Function or object describing how to validate this schematype.
+ *
+ * @api public
+ * @property validate
+ * @memberOf SchemaTypeOptions
+ * @type Function|Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'validate', opts);
+
+/**
+ * If true, attach a required validator to this path, which ensures this path
+ * path cannot be set to a nullish value. If a function, Mongoose calls the
+ * function and only checks for nullish values if the function returns a truthy value.
+ *
+ * @api public
+ * @property required
+ * @memberOf SchemaTypeOptions
+ * @type Function|Boolean
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'required', opts);
+
+/**
+ * The default value for this path. If a function, Mongoose executes the function
+ * and uses the return value as the default.
+ *
+ * @api public
+ * @property default
+ * @memberOf SchemaTypeOptions
+ * @type Function|Any
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'default', opts);
+
+/**
+ * The model that `populate()` should use if populating this path.
+ *
+ * @api public
+ * @property ref
+ * @memberOf SchemaTypeOptions
+ * @type Function|String
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'ref', opts);
+
+/**
+ * Whether to include or exclude this path by default when loading documents
+ * using `find()`, `findOne()`, etc.
+ *
+ * @api public
+ * @property select
+ * @memberOf SchemaTypeOptions
+ * @type Boolean|Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'select', opts);
+
+/**
+ * If truthy, Mongoose will build an index on this path when the model is
+ * compiled.
+ *
+ * @api public
+ * @property index
+ * @memberOf SchemaTypeOptions
+ * @type Boolean|Number|Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'index', opts);
+
+/**
+ * If truthy, Mongoose will build a unique index on this path when the
+ * model is compiled. [The `unique` option is **not** a validator](/docs/validation.html#the-unique-option-is-not-a-validator).
+ *
+ * @api public
+ * @property unique
+ * @memberOf SchemaTypeOptions
+ * @type Boolean|Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'unique', opts);
+
+/**
+ * If truthy, Mongoose will disallow changes to this path once the document
+ * is saved to the database for the first time. Read more about [immutability in Mongoose here](http://thecodebarbarian.com/whats-new-in-mongoose-5-6-immutable-properties.html).
+ *
+ * @api public
+ * @property immutable
+ * @memberOf SchemaTypeOptions
+ * @type Function|Boolean
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'immutable', opts);
+
+/**
+ * If truthy, Mongoose will build a sparse index on this path.
+ *
+ * @api public
+ * @property sparse
+ * @memberOf SchemaTypeOptions
+ * @type Boolean|Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'sparse', opts);
+
+/**
+ * If truthy, Mongoose will build a text index on this path.
+ *
+ * @api public
+ * @property text
+ * @memberOf SchemaTypeOptions
+ * @type Boolean|Number|Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'text', opts);
+
+module.exports = SchemaTypeOptions;
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index 41fb876fd7e..17a1c0da466 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1739,6 +1739,8 @@ Schema.prototype.virtual = function(name, options) {
       });
       break;
     }
+
+    cur += '.' + parts[i + 1];
   }
 
   return virtuals[name];
diff --git a/lib/schematype.js b/lib/schematype.js
index 095e862c553..56464f1695d 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -5,6 +5,7 @@
  */
 
 const MongooseError = require('./error/index');
+const SchemaTypeOptions = require('./options/SchemaTypeOptions');
 const $exists = require('./schema/operators/exists');
 const $type = require('./schema/operators/type');
 const get = require('./helpers/get');
@@ -42,17 +43,18 @@ function SchemaType(path, options, instance) {
     this.constructor.getters.slice() :
     [];
   this.setters = [];
-  this.options = options;
+  this.options = new SchemaTypeOptions(options);
   this._index = null;
   this.selected;
-  if (utils.hasUserDefinedProperty(options, 'immutable')) {
-    this.$immutable = options.immutable;
+  if (utils.hasUserDefinedProperty(this.options, 'immutable')) {
+    this.$immutable = this.options.immutable;
 
     handleImmutable(this);
   }
 
-  for (const prop in options) {
-    if (this[prop] && typeof this[prop] === 'function') {
+  const keys = Object.keys(this.options);
+  for (const prop of keys) {
+    if (utils.hasUserDefinedProperty(this.options, prop) && typeof this[prop] === 'function') {
       // { unique: true, index: true }
       if (prop === 'index' && this._index) {
         if (options.index === false) {

From d19b849d3f669ab74787e529edba5aaa8d114057 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Oct 2019 22:59:23 -0700
Subject: [PATCH 0043/2348] test: add test coverage for `parallelLimit()`

---
 lib/helpers/parallelLimit.js |  6 ++++-
 test/parallelLimit.test.js   | 43 ++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 1 deletion(-)
 create mode 100644 test/parallelLimit.test.js

diff --git a/lib/helpers/parallelLimit.js b/lib/helpers/parallelLimit.js
index 06907928997..9b07c028bf8 100644
--- a/lib/helpers/parallelLimit.js
+++ b/lib/helpers/parallelLimit.js
@@ -11,11 +11,15 @@ function parallelLimit(fns, limit, callback) {
   let numFinished = 0;
   let error = null;
 
+  if (limit <= 0) {
+    throw new Error('Limit must be positive');
+  }
+
   if (fns.length === 0) {
     return callback(null, []);
   }
 
-  for (let i = 0; i < fns.length && i <= limit; ++i) {
+  for (let i = 0; i < fns.length && i < limit; ++i) {
     _start();
   }
 
diff --git a/test/parallelLimit.test.js b/test/parallelLimit.test.js
new file mode 100644
index 00000000000..af532d7b342
--- /dev/null
+++ b/test/parallelLimit.test.js
@@ -0,0 +1,43 @@
+'use strict';
+
+const assert = require('assert');
+const parallelLimit = require('../lib/helpers/parallelLimit');
+
+describe('parallelLimit', function() {
+  it('works with zero functions', function(done) {
+    parallelLimit([], 1, (err, res) => {
+      assert.ifError(err);
+      assert.deepEqual(res, []);
+      done();
+    });
+  });
+
+  it('executes functions in parallel', function(done) {
+    let called = 0;
+    const fns = [
+      cb => {
+        setTimeout(() => {
+          ++called;
+          setTimeout(cb, 0);
+        }, 100);
+      },
+      cb => {
+        setTimeout(() => {
+          ++called;
+          setTimeout(cb, 0);
+        }, 100);
+      },
+      cb => {
+        assert.equal(called, 2);
+        ++called;
+        setTimeout(cb, 100);
+      }
+    ];
+
+    parallelLimit(fns, 2, (err) => {
+      assert.ifError(err);
+      assert.equal(called, 3);
+      done();
+    });
+  });
+});
\ No newline at end of file

From f277d948f6ba6237a7ddd7132102851c0036212b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 5 Oct 2019 11:05:34 -0700
Subject: [PATCH 0044/2348] test(update): repro #8063

---
 test/model.update.test.js | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index dc2da0c1c5b..961409fbb08 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3348,4 +3348,38 @@ describe('model: updateOne: ', function() {
       assert.equal(docs[1].arr.length, 1);
     });
   });
+
+  it('update embedded discriminator path if key in $elemMatch (gh-8063)', function() {
+    const slideSchema = new Schema({
+      type: { type: String },
+      commonField: String
+    }, { discriminatorKey: 'type' });
+    const schema = new Schema({ slides: [slideSchema] });
+
+    const slidesSchema = schema.path('slides');
+    slidesSchema.discriminator('typeA', new Schema({ a: String }));
+    slidesSchema.discriminator('typeB', new Schema({ b: String }));
+
+    const MyModel = db.model('gh8063', schema);
+    return co(function*() {
+      const doc = yield MyModel.create({
+        slides: [{ type: 'typeA', a: 'oldValue1', commonField: 'oldValue2' }]
+      });
+
+      const filter = {
+        slides: { $elemMatch: { _id: doc.slides[0]._id, type: 'typeA' } }
+      };
+      const update = {
+        'slides.$.a': 'newValue1',
+        'slides.$.commonField': 'newValue2'
+      };
+      yield MyModel.updateOne(filter, update);
+
+      const updatedDoc = yield MyModel.findOne();
+      assert.equal(updatedDoc.slides.length, 1);
+      assert.equal(updatedDoc.slides[0].type, 'typeA');
+      assert.equal(updatedDoc.slides[0].a, 'newValue1');
+      assert.equal(updatedDoc.slides[0].commonField, 'newValue2');
+    });
+  });
 });
\ No newline at end of file

From 523c18142b2767ef83a8f6739d21e44fbfeca9f0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 5 Oct 2019 11:05:47 -0700
Subject: [PATCH 0045/2348] fix(update): support updating array embedded
 discriminator props if discriminator key in $elemMatch

Fix #8063
---
 lib/helpers/query/getEmbeddedDiscriminatorPath.js | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/query/getEmbeddedDiscriminatorPath.js b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
index 822f211bbd4..8214158377b 100644
--- a/lib/helpers/query/getEmbeddedDiscriminatorPath.js
+++ b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
@@ -22,21 +22,29 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
     if (schematype == null) {
       continue;
     }
+
     type = schema.pathType(subpath);
     if ((schematype.$isSingleNested || schematype.$isMongooseDocumentArrayElement) &&
         schematype.schema.discriminators != null) {
       const discriminators = schematype.schema.discriminators;
-      const discriminatorValuePath = subpath + '.' +
-        get(schematype, 'schema.options.discriminatorKey');
+      const key = get(schematype, 'schema.options.discriminatorKey');
+      const discriminatorValuePath = subpath + '.' + key;
       const discriminatorFilterPath =
         discriminatorValuePath.replace(/\.\d+\./, '.');
       let discriminatorKey = null;
+
       if (discriminatorValuePath in filter) {
         discriminatorKey = filter[discriminatorValuePath];
       }
       if (discriminatorFilterPath in filter) {
         discriminatorKey = filter[discriminatorFilterPath];
       }
+      const wrapperPath = subpath.replace(/\.\d+$/, '');
+      if (schematype.$isMongooseDocumentArrayElement &&
+          get(filter[wrapperPath], '$elemMatch.' + key) != null) {
+        discriminatorKey = filter[wrapperPath].$elemMatch[key];
+      }
+
       if (discriminatorKey == null || discriminators[discriminatorKey] == null) {
         continue;
       }

From 166cd883153ca35bf7549a7f3c074e2459a8dad0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 6 Oct 2019 18:07:36 -0400
Subject: [PATCH 0046/2348] refactor: use SchemaStringOptions class for string
 schematype options re: #8012

---
 lib/options/SchemaStringOptions.js | 82 ++++++++++++++++++++++++++++++
 lib/options/SchemaTypeOptions.js   | 12 +++++
 lib/schema/string.js               |  4 +-
 lib/schematype.js                  |  4 +-
 4 files changed, 100 insertions(+), 2 deletions(-)
 create mode 100644 lib/options/SchemaStringOptions.js

diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
new file mode 100644
index 00000000000..54ca35edfba
--- /dev/null
+++ b/lib/options/SchemaStringOptions.js
@@ -0,0 +1,82 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+class SchemaStringOptions extends SchemaTypeOptions {}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * Array of allowed values for this path
+ *
+ * @api public
+ * @property enum
+ * @memberOf SchemaStringOptions
+ * @type Array
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'enum', opts);
+
+/**
+ * Attach a validator that succeeds if the data string matches the given regular
+ * expression, and fails otherwise.
+ *
+ * @api public
+ * @property match
+ * @memberOf SchemaStringOptions
+ * @type RegExp
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'match', opts);
+
+/**
+ * If truthy, Mongoose will add a custom setter that lowercases this string
+ * using JavaScript's built-in `String#toLowerCase()`.
+ *
+ * @api public
+ * @property lowercase
+ * @memberOf SchemaStringOptions
+ * @type Boolean
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'lowercase', opts);
+
+/**
+ * If truthy, Mongoose will add a custom setter that removes leading and trailing
+ * whitespace using JavaScript's built-in `String#trim()`.
+ *
+ * @api public
+ * @property trim
+ * @memberOf SchemaStringOptions
+ * @type Boolean
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'trim', opts);
+
+/**
+ * If truthy, Mongoose will add a custom setter that uppercases this string
+ * using JavaScript's built-in `String#toUpperCase()`.
+ *
+ * @api public
+ * @property uppercase
+ * @memberOf SchemaStringOptions
+ * @type Boolean
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'uppercase', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaStringOptions;
\ No newline at end of file
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 97e6206cf17..51bfd6b571b 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -18,6 +18,18 @@ const opts = {
   value: null
 };
 
+/**
+ * The type to cast this path to.
+ *
+ * @api public
+ * @property type
+ * @memberOf SchemaTypeOptions
+ * @type Function|String|Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'type', opts);
+
 /**
  * Function or object describing how to validate this schematype.
  *
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 422558cce85..c45d08f6dfb 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -5,13 +5,14 @@
  */
 
 const SchemaType = require('../schematype');
-const CastError = SchemaType.CastError;
 const MongooseError = require('../error/index');
+const SchemaStringOptions = require('../options/SchemaStringOptions');
 const castString = require('../cast/string');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
 
+const CastError = SchemaType.CastError;
 let Document;
 
 /**
@@ -48,6 +49,7 @@ SchemaString.prototype.constructor = SchemaString;
  */
 
 SchemaString._cast = castString;
+SchemaString.OptionsConstructor = SchemaStringOptions;
 
 /**
  * Get/set the function used to cast arbitrary values to strings.
diff --git a/lib/schematype.js b/lib/schematype.js
index 56464f1695d..dea567766ca 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -43,7 +43,9 @@ function SchemaType(path, options, instance) {
     this.constructor.getters.slice() :
     [];
   this.setters = [];
-  this.options = new SchemaTypeOptions(options);
+
+  const Options = this.OptionsConstructor || SchemaTypeOptions;
+  this.options = new Options(options);
   this._index = null;
   this.selected;
   if (utils.hasUserDefinedProperty(this.options, 'immutable')) {

From 2d0955dd60173cf2ee3683656976b0b8a617b8db Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 6 Oct 2019 18:20:12 -0400
Subject: [PATCH 0047/2348] refactor: use SchemaNumberOptions class for
 schematype number re: #8012

---
 lib/options/SchemaNumberOptions.js | 44 ++++++++++++++++++++++++++++++
 lib/schema/number.js               |  2 ++
 lib/schema/string.js               |  2 +-
 lib/schematype.js                  |  6 ++++
 4 files changed, 53 insertions(+), 1 deletion(-)
 create mode 100644 lib/options/SchemaNumberOptions.js

diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
new file mode 100644
index 00000000000..2186a83740b
--- /dev/null
+++ b/lib/options/SchemaNumberOptions.js
@@ -0,0 +1,44 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+class SchemaNumberOptions extends SchemaTypeOptions {}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * If set, Mongoose adds a validator that checks that this path is at least the
+ * given `min`.
+ *
+ * @api public
+ * @property min
+ * @memberOf SchemaNumberOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaNumberOptions.prototype, 'min', opts);
+
+/**
+ * If set, Mongoose adds a validator that checks that this path is at least the
+ * given `max`.
+ *
+ * @api public
+ * @property max
+ * @memberOf SchemaNumberOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaNumberOptions.prototype, 'max', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaNumberOptions;
\ No newline at end of file
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 8f9100d268c..62729eca174 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -5,6 +5,7 @@
  */
 
 const MongooseError = require('../error/index');
+const SchemaNumberOptions = require('../options/SchemaNumberOptions');
 const SchemaType = require('../schematype');
 const castNumber = require('../cast/number');
 const handleBitwiseOperator = require('./operators/bitwise');
@@ -106,6 +107,7 @@ SchemaNumber.schemaName = 'Number';
  */
 SchemaNumber.prototype = Object.create(SchemaType.prototype);
 SchemaNumber.prototype.constructor = SchemaNumber;
+SchemaNumber.prototype.OptionsConstructor = SchemaNumberOptions;
 
 /*!
  * ignore
diff --git a/lib/schema/string.js b/lib/schema/string.js
index c45d08f6dfb..fe3e9568a07 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -43,13 +43,13 @@ SchemaString.schemaName = 'String';
  */
 SchemaString.prototype = Object.create(SchemaType.prototype);
 SchemaString.prototype.constructor = SchemaString;
+SchemaString.prototype.OptionsConstructor = SchemaStringOptions;
 
 /*!
  * ignore
  */
 
 SchemaString._cast = castString;
-SchemaString.OptionsConstructor = SchemaStringOptions;
 
 /**
  * Get/set the function used to cast arbitrary values to strings.
diff --git a/lib/schematype.js b/lib/schematype.js
index dea567766ca..2cd0caf0858 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -98,6 +98,12 @@ function SchemaType(path, options, instance) {
   });
 }
 
+/*!
+ * ignore
+ */
+
+SchemaType.prototype.OptionsConstructor = SchemaTypeOptions;
+
 /**
  * Get/set the function used to cast arbitrary values to this type.
  *

From d5e0c73cdf13ea6ff4ab7a77a1d09690006377f9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Oct 2019 13:13:30 -0400
Subject: [PATCH 0048/2348] refactor: use options constructor for array,
 buffer, date schematypes re: #8012

---
 lib/options/SchemaArrayOptions.js  | 31 +++++++++++++++++
 lib/options/SchemaBufferOptions.js | 30 ++++++++++++++++
 lib/options/SchemaDateOptions.js   | 56 ++++++++++++++++++++++++++++++
 lib/options/SchemaNumberOptions.js |  2 +-
 lib/schema/array.js                |  2 ++
 lib/schema/buffer.js               |  7 ++--
 lib/schema/date.js                 |  5 +--
 7 files changed, 127 insertions(+), 6 deletions(-)
 create mode 100644 lib/options/SchemaArrayOptions.js
 create mode 100644 lib/options/SchemaBufferOptions.js
 create mode 100644 lib/options/SchemaDateOptions.js

diff --git a/lib/options/SchemaArrayOptions.js b/lib/options/SchemaArrayOptions.js
new file mode 100644
index 00000000000..330ac2db5e9
--- /dev/null
+++ b/lib/options/SchemaArrayOptions.js
@@ -0,0 +1,31 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+class SchemaArrayOptions extends SchemaTypeOptions {}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * If this is an array of strings, an array of allowed values for this path.
+ * Throws an error if this array isn't an array of strings.
+ *
+ * @api public
+ * @property enum
+ * @memberOf SchemaArrayOptions
+ * @type Array
+ * @instance
+ */
+
+Object.defineProperty(SchemaArrayOptions.prototype, 'enum', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaArrayOptions;
\ No newline at end of file
diff --git a/lib/options/SchemaBufferOptions.js b/lib/options/SchemaBufferOptions.js
new file mode 100644
index 00000000000..4ee8957ba2a
--- /dev/null
+++ b/lib/options/SchemaBufferOptions.js
@@ -0,0 +1,30 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+class SchemaBufferOptions extends SchemaTypeOptions {}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * Set the default subtype for this buffer.
+ *
+ * @api public
+ * @property subtype
+ * @memberOf SchemaBufferOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaBufferOptions.prototype, 'subtype', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaBufferOptions;
\ No newline at end of file
diff --git a/lib/options/SchemaDateOptions.js b/lib/options/SchemaDateOptions.js
new file mode 100644
index 00000000000..5334e5f66c3
--- /dev/null
+++ b/lib/options/SchemaDateOptions.js
@@ -0,0 +1,56 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+class SchemaDateOptions extends SchemaTypeOptions {}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * If set, Mongoose adds a validator that checks that this path is after the
+ * given `min`.
+ *
+ * @api public
+ * @property min
+ * @memberOf SchemaDateOptions
+ * @type Date
+ * @instance
+ */
+
+Object.defineProperty(SchemaDateOptions.prototype, 'min', opts);
+
+/**
+ * If set, Mongoose adds a validator that checks that this path is before the
+ * given `max`.
+ *
+ * @api public
+ * @property max
+ * @memberOf SchemaDateOptions
+ * @type Date
+ * @instance
+ */
+
+Object.defineProperty(SchemaDateOptions.prototype, 'max', opts);
+
+/**
+ * If set, Mongoose creates a TTL index on this path.
+ *
+ * @api public
+ * @property expires
+ * @memberOf SchemaDateOptions
+ * @type Date
+ * @instance
+ */
+
+Object.defineProperty(SchemaDateOptions.prototype, 'expires', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaDateOptions;
\ No newline at end of file
diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index 2186a83740b..6bb57e3cd98 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -25,7 +25,7 @@ const opts = {
 Object.defineProperty(SchemaNumberOptions.prototype, 'min', opts);
 
 /**
- * If set, Mongoose adds a validator that checks that this path is at least the
+ * If set, Mongoose adds a validator that checks that this path is less than the
  * given `max`.
  *
  * @api public
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 3ffc7cae585..718961df23d 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -7,6 +7,7 @@
 const $exists = require('./operators/exists');
 const $type = require('./operators/type');
 const MongooseError = require('../error/mongooseError');
+const SchemaArrayOptions = require('../options/SchemaArrayOptions');
 const SchemaType = require('../schematype');
 const CastError = SchemaType.CastError;
 const Mixed = require('./mixed');
@@ -134,6 +135,7 @@ SchemaArray.options = { castNonArrays: true };
  */
 SchemaArray.prototype = Object.create(SchemaType.prototype);
 SchemaArray.prototype.constructor = SchemaArray;
+SchemaArray.prototype.OptionsConstructor = SchemaArrayOptions;
 
 /*!
  * ignore
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 6b6868ef46e..69ccdaa8af5 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -4,14 +4,14 @@
 
 'use strict';
 
+const MongooseBuffer = require('../types/buffer');
+const SchemaBufferOptions = require('../options/SchemaBufferOptions');
+const SchemaType = require('../schematype');
 const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
 
-const MongooseBuffer = require('../types/buffer');
-const SchemaType = require('../schematype');
-
 const Binary = MongooseBuffer.Binary;
 const CastError = SchemaType.CastError;
 let Document;
@@ -42,6 +42,7 @@ SchemaBuffer.schemaName = 'Buffer';
  */
 SchemaBuffer.prototype = Object.create(SchemaType.prototype);
 SchemaBuffer.prototype.constructor = SchemaBuffer;
+SchemaBuffer.prototype.OptionsConstructor = SchemaBufferOptions;
 
 /*!
  * ignore
diff --git a/lib/schema/date.js b/lib/schema/date.js
index 576039b4fb8..6a0e9aae46b 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -5,11 +5,11 @@
 'use strict';
 
 const MongooseError = require('../error/index');
+const SchemaDateOptions = require('../options/SchemaDateOptions');
+const SchemaType = require('../schematype');
 const castDate = require('../cast/date');
 const utils = require('../utils');
 
-const SchemaType = require('../schematype');
-
 const CastError = SchemaType.CastError;
 
 /**
@@ -38,6 +38,7 @@ SchemaDate.schemaName = 'Date';
  */
 SchemaDate.prototype = Object.create(SchemaType.prototype);
 SchemaDate.prototype.constructor = SchemaDate;
+SchemaDate.prototype.OptionsConstructor = SchemaDateOptions;
 
 /*!
  * ignore

From fb66f3afd67070a8512ecbb404e6ea69ecb275c3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Oct 2019 14:29:59 -0400
Subject: [PATCH 0049/2348] fix: use options constructor class for all
 schematypes

Fix #8012
---
 lib/options/SchemaObjectIdOptions.js | 30 ++++++++++++++++++++++++++++
 lib/schema/objectid.js               |  4 +++-
 2 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 lib/options/SchemaObjectIdOptions.js

diff --git a/lib/options/SchemaObjectIdOptions.js b/lib/options/SchemaObjectIdOptions.js
new file mode 100644
index 00000000000..67ecc8a863d
--- /dev/null
+++ b/lib/options/SchemaObjectIdOptions.js
@@ -0,0 +1,30 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+class SchemaObjectIdOptions extends SchemaTypeOptions {}
+
+const opts = {
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: null
+};
+
+/**
+ * If truthy, uses Mongoose's default built-in ObjectId path.
+ *
+ * @api public
+ * @property auto
+ * @memberOf SchemaObjectIdOptions
+ * @type Boolean
+ * @instance
+ */
+
+Object.defineProperty(SchemaObjectIdOptions.prototype, 'auto', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaObjectIdOptions;
\ No newline at end of file
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index 2a07c118d2a..ae20493159b 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -4,8 +4,9 @@
 
 'use strict';
 
-const castObjectId = require('../cast/objectid');
+const SchemaObjectIdOptions = require('../options/SchemaObjectIdOptions');
 const SchemaType = require('../schematype');
+const castObjectId = require('../cast/objectid');
 const oid = require('../types/objectid');
 const utils = require('../utils');
 
@@ -49,6 +50,7 @@ ObjectId.schemaName = 'ObjectId';
  */
 ObjectId.prototype = Object.create(SchemaType.prototype);
 ObjectId.prototype.constructor = ObjectId;
+ObjectId.prototype.OptionsConstructor = SchemaObjectIdOptions;
 
 /**
  * Attaches a getter for all ObjectId instances

From 9b4a323e09b7c8a51797246e142148ea765ef48f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Oct 2019 14:51:58 -0400
Subject: [PATCH 0050/2348] test(schema): repro #8219

---
 test/schema.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 2cc470bf24c..02c6c22baa9 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2126,4 +2126,13 @@ describe('schema', function() {
     const testKo = new TestKo({field: 'upper'});
     assert.equal(testKo.field, 'UPPER');
   });
+
+  it('required with nullish value (gh-8219)', function() {
+    const schema = Schema({
+      name: { type: String, required: void 0 },
+      age: { type: Number, required: null }
+    });
+    assert.strictEqual(schema.path('name').isRequired, false);
+    assert.strictEqual(schema.path('age').isRequired, false);
+  });
 });

From 7a2027652b8f443a9247dbb85ef0e988bbddb3ab Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Oct 2019 14:59:34 -0400
Subject: [PATCH 0051/2348] fix(schema): handle `required: null` and `required:
 undefined` as `required: false`

Fix #8219
---
 lib/schematype.js | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/lib/schematype.js b/lib/schematype.js
index 2cd0caf0858..fbce0e0dce6 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -798,6 +798,17 @@ const handleIsAsync = util.deprecate(function handleIsAsync() {},
 
 SchemaType.prototype.required = function(required, message) {
   let customOptions = {};
+
+  if (arguments.length > 0 && required == null) {
+    this.validators = this.validators.filter(function(v) {
+      return v.validator !== this.requiredValidator;
+    }, this);
+
+    this.isRequired = false;
+    delete this.originalRequiredValue;
+    return this;
+  }
+
   if (typeof required === 'object') {
     customOptions = required;
     message = customOptions.message || message;

From c3538eb7317c69b1635a09e0c66ecf910b25de1e Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Tue, 8 Oct 2019 22:00:42 +0300
Subject: [PATCH 0052/2348] feat(schema): make pojo paths optionally become
 subdoc instead of Mixed

- default behaves as previous releases did
- embeddeddocument test copied to cover declarative syntax
---
 lib/schema.js                                 | 44 +++++++++-----
 .../types.embeddeddocumentdeclarative.test.js | 58 +++++++++++++++++++
 2 files changed, 89 insertions(+), 13 deletions(-)
 create mode 100644 test/types.embeddeddocumentdeclarative.test.js

diff --git a/lib/schema.js b/lib/schema.js
index 17a1c0da466..d18a261dfa7 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -62,6 +62,7 @@ let id = 0;
  * - [toJSON](/docs/guide.html#toJSON) - object - no default
  * - [toObject](/docs/guide.html#toObject) - object - no default
  * - [typeKey](/docs/guide.html#typeKey) - string - defaults to 'type'
+ * - [typePojoToMixed](/docs/guide.html#typePojoToMixed) - boolean - defaults to true
  * - [useNestedStrict](/docs/guide.html#useNestedStrict) - boolean - defaults to false
  * - [validateBeforeSave](/docs/guide.html#validateBeforeSave) - bool - defaults to `true`
  * - [versionKey](/docs/guide.html#versionKey): string - defaults to "__v"
@@ -363,7 +364,8 @@ Schema.prototype.defaultOptions = function(options) {
     _id: true,
     noVirtualId: false, // deprecated, use { id: false }
     id: true,
-    typeKey: 'type'
+    typeKey: 'type',
+    typePojoToMixed: true
   }, utils.clone(options));
 
   if (options.read) {
@@ -423,23 +425,39 @@ Schema.prototype.add = function add(obj, prefix) {
         '`, got value "' + obj[key][0] + '"');
     }
 
-    if (utils.isPOJO(obj[key]) &&
-        (!obj[key][this.options.typeKey] || (this.options.typeKey === 'type' && obj[key].type.type))) {
-      if (Object.keys(obj[key]).length) {
-        // nested object { last: { name: String }}
-        this.nested[fullPath] = true;
-        this.add(obj[key], fullPath + '.');
+    if (!utils.isPOJO(obj[key])) {
+      // Special-case: Non-POJO definitely a path so leaf at this node
+      if (prefix) {
+        this.nested[prefix.substr(0, prefix.length - 1)] = true;
+      }
+      this.path(prefix + key, obj[key]);
+    } else if (Object.keys(obj[key]).length < 1) {
+      // Special-case: {} always interpreted as Mixed path so leaf at this node
+      if (prefix) {
+        this.nested[prefix.substr(0, prefix.length - 1)] = true;
+      }
+      this.path(fullPath, obj[key]); // mixed type
+    } else if (!obj[key][this.options.typeKey] || (this.options.typeKey === 'type' && obj[key].type.type)) {
+      // Special-case: POJO with no bona-fide type key - interpret as tree of deep paths so recurse
+      // nested object { last: { name: String }}
+      this.nested[fullPath] = true;
+      this.add(obj[key], fullPath + '.');
+    } else {
+      // There IS a bona-fide type key that may also be a POJO
+      if(!this.options.typePojoToMixed && utils.isPOJO(obj[key][this.options.typeKey])) {
+        // If a POJO is the value of a type key, make it a subdocument
+        if (prefix) {
+          this.nested[prefix.substr(0, prefix.length - 1)] = true;
+        }
+        const schemaWrappedPath = Object.assign({}, obj[key], { type: new Schema(obj[key][this.options.typeKey]) });
+        this.path(prefix + key, schemaWrappedPath);
       } else {
+        // Either the type is non-POJO or we interpret it as Mixed anyway
         if (prefix) {
           this.nested[prefix.substr(0, prefix.length - 1)] = true;
         }
-        this.path(fullPath, obj[key]); // mixed type
-      }
-    } else {
-      if (prefix) {
-        this.nested[prefix.substr(0, prefix.length - 1)] = true;
+        this.path(prefix + key, obj[key]);
       }
-      this.path(prefix + key, obj[key]);
     }
   }
 
diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
new file mode 100644
index 00000000000..08cb9144d23
--- /dev/null
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -0,0 +1,58 @@
+'use strict';
+
+/**
+ * Module dependencies.
+ */
+
+const assert = require('assert');
+const start = require('./common');
+
+const mongoose = start.mongoose;
+const Schema = mongoose.Schema;
+
+/**
+ * Test.
+ */
+
+describe('types.embeddeddocumentdeclarative', function() {
+  let GrandChildSchema;
+  let ChildSchema;
+  let ParentSchema;
+
+  before(function() {
+    GrandChildSchema = {
+      name: String
+    };
+
+    ChildSchema = {
+      name: String,
+      children: [GrandChildSchema]
+    };
+
+    ParentSchema = new Schema({
+      name: String,
+      typePojoToMixed: false,
+      child: ChildSchema
+    });
+
+    mongoose.model('Parent-7494-EmbeddedDeclarative', ParentSchema);
+  });
+
+  it('returns a proper ownerDocument (gh-7494)', function(done) {
+    const Parent = mongoose.model('Parent-7494-EmbeddedDeclarative');
+    const p = new Parent({
+      name: 'Parent Parentson',
+      child: {
+        name: 'Child Parentson',
+        children: [
+          {
+            name: 'GrandChild Parentson'
+          }
+        ]
+      }
+    });
+
+    assert.equal(p._id, p.child.children[0].ownerDocument()._id);
+    done();
+  });
+});

From 9475dce55fad82ea7490e685711b55be942e7e21 Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Tue, 8 Oct 2019 22:31:43 +0300
Subject: [PATCH 0053/2348] style: fix lint in schema add

---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index d18a261dfa7..8015554c1c7 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -444,7 +444,7 @@ Schema.prototype.add = function add(obj, prefix) {
       this.add(obj[key], fullPath + '.');
     } else {
       // There IS a bona-fide type key that may also be a POJO
-      if(!this.options.typePojoToMixed && utils.isPOJO(obj[key][this.options.typeKey])) {
+      if (!this.options.typePojoToMixed && utils.isPOJO(obj[key][this.options.typeKey])) {
         // If a POJO is the value of a type key, make it a subdocument
         if (prefix) {
           this.nested[prefix.substr(0, prefix.length - 1)] = true;

From 402db1a8f455306b1e0146d3fa3c776e3ee50da0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Oct 2019 13:04:18 -0400
Subject: [PATCH 0054/2348] fix(model): support passing `options` to
 `Model.remove()`

Fix #8211
---
 lib/model.js                   | 14 +++++++++++---
 test/docs/transactions.test.js |  3 ++-
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 238b3d73225..eca0693a4b9 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -874,6 +874,8 @@ Model.prototype.$__where = function _where(where) {
  *        assert.ok(err)
  *     })
  *
+ * @param {Object} [options]
+ * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this operation. If not specified, defaults to the [document's associated session](api.html#document_Document-$session).
  * @param {function(err,product)} [fn] optional callback
  * @return {Promise} Promise
  * @api public
@@ -1819,21 +1821,28 @@ Model.translateAliases = function translateAliases(fields) {
  * not execute [document middleware](/docs/middleware.html#types-of-middleware).
  *
  * @param {Object} conditions
+ * @param {Object} [options]
+ * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this operation.
  * @param {Function} [callback]
  * @return {Query}
  * @api public
  */
 
-Model.remove = function remove(conditions, callback) {
+Model.remove = function remove(conditions, options, callback) {
   _checkContext(this, 'remove');
 
   if (typeof conditions === 'function') {
     callback = conditions;
     conditions = {};
+    options = null;
+  } else if (typeof options === 'function') {
+    callback = options;
+    options = null;
   }
 
   // get the mongodb collection object
   const mq = new this.Query({}, {}, this, this.collection);
+  mq.setOptions(options);
 
   callback = this.$handleCallbackError(callback);
 
@@ -1908,8 +1917,7 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
     callback = conditions;
     conditions = {};
     options = null;
-  }
-  else if (typeof options === 'function') {
+  } else if (typeof options === 'function') {
     callback = options;
     options = null;
   }
diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index 32034a4764e..8b810542ced 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -21,7 +21,8 @@ describe('transactions', function() {
     return db.
       then(() => {
         // Skip if not a repl set
-        if (db.client.topology.constructor.name !== 'ReplSet') {
+        if (db.client.topology.constructor.name !== 'ReplSet' &&
+            !db.client.topology.s.description.type.includes('ReplicaSet')) {
           _skipped = true;
           this.skip();
 

From ede5aefd154de9c17740a55da036c04fc28366b7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Oct 2019 13:39:37 -0400
Subject: [PATCH 0055/2348] chore: release 5.7.4

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index a7449fd590a..518e423493b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.7.4 / 2019-10-09
+==================
+ * fix(schema): handle `required: null` and `required: undefined` as `required: false` #8219
+ * fix(update): support updating array embedded discriminator props if discriminator key in $elemMatch #8063
+ * fix(populate): allow accessing populate virtual prop underneath array when virtual defined on top level #8198
+ * fix(model): support passing `options` to `Model.remove()` #8211
+ * fix(document): handle `Document#set()` merge option when setting underneath single nested schema #8201
+ * fix: use options constructor class for all schematypes #8012
+
 5.7.3 / 2019-09-30
 ==================
  * fix: make CoreMongooseArray#includes() handle `fromIndex` parameter #8203
diff --git a/package.json b/package.json
index 682feddea58..b7086610300 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.4-pre",
+  "version": "5.7.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From cc10e0dc441f469330c1af2822d171fcd6fa8f89 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Oct 2019 18:27:30 -0400
Subject: [PATCH 0056/2348] test(query): repro #8222

---
 test/query.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index 5a67e45eb32..ba5bd1efadc 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3550,4 +3550,13 @@ describe('Query', function() {
       });
     });
   });
+
+  it('query with top-level _bsontype (gh-8222)', function() {
+    const userSchema = Schema({ token: String });
+    const User = db.model('gh8222', userSchema);
+
+    return User.create({ token: 'rightToken' }).
+      then(() => User.findOne({ token: 'wrongToken', _bsontype: 'a' })).
+      then(doc => assert.ok(!doc));
+  });
 });

From f3eca5b94d822225c04e96cbeed9f095afb3c31c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Oct 2019 18:41:25 -0400
Subject: [PATCH 0057/2348] fix(query): delete top-level `_bsontype` property
 in queries to prevent silent empty queries

Fix #8222
---
 lib/cast.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/cast.js b/lib/cast.js
index 928fe9d1ba4..3dfd651acd2 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -27,6 +27,12 @@ module.exports = function cast(schema, obj, options, context) {
     throw new Error('Query filter must be an object, got an array ', util.inspect(obj));
   }
 
+  // bson 1.x has the unfortunate tendency to remove filters that have a top-level
+  // `_bsontype` property. Should remove this when we upgrade to bson 4.x. See gh-8222
+  if (obj.hasOwnProperty('_bsontype')) {
+    delete obj._bsontype;
+  }
+
   const paths = Object.keys(obj);
   let i = paths.length;
   let _keys;

From ee22c09792280e030deb3d74fc83f3c86aa32396 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Oct 2019 18:42:35 -0400
Subject: [PATCH 0058/2348] chore: now working on 5.7.5

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index b7086610300..11dada08bf3 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.4",
+  "version": "5.7.5-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From dd83d70c4a8977ac9227e45193607d2757b2d807 Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Thu, 10 Oct 2019 04:24:05 +0300
Subject: [PATCH 0059/2348] test(schema): cover most code paths in Schema.add

- verify Mixed should stay Mixed by default
- verify subschema with option default overridden
- verify nested paths in both options behave the same
- verify field-named-type special-case in both options
---
 .../types.embeddeddocumentdeclarative.test.js | 124 ++++++++++++++----
 1 file changed, 97 insertions(+), 27 deletions(-)

diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
index 08cb9144d23..4d16d5c3224 100644
--- a/test/types.embeddeddocumentdeclarative.test.js
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -15,44 +15,114 @@ const Schema = mongoose.Schema;
  */
 
 describe('types.embeddeddocumentdeclarative', function() {
-  let GrandChildSchema;
-  let ChildSchema;
-  let ParentSchema;
-
-  before(function() {
-    GrandChildSchema = {
-      name: String
+  describe('with a parent with a field with type set to a POJO', function() {
+    const ChildSchemaDef = {
+      name: String,
     };
 
-    ChildSchema = {
+    const ParentSchemaDef = {
       name: String,
-      children: [GrandChildSchema]
+      child: {
+        type: ChildSchemaDef,
+      }
     };
 
-    ParentSchema = new Schema({
-      name: String,
-      typePojoToMixed: false,
-      child: ChildSchema
+    describe('with the default legacy behavior (typePojoToMixed=true)', function() {
+      const ParentSchema = new mongoose.Schema(ParentSchemaDef);
+      it('interprets the POJO as Mixed (gh-7494)', function(done) {
+        assert.equal(ParentSchema.paths.child.instance, 'Mixed');
+        done();
+      });
+      it('does not enforce provided schema on the child path (gh-7494)', function(done) {
+        const ParentModel = mongoose.model('ParentModel-7494-EmbeddedDeclarativeMixed', ParentSchema);
+        const swampGuide = new ParentModel({
+          name: 'Swamp Guide',
+          child: {
+            name: 'Tingle',
+            mixedUp: 'very',
+          }
+        });
+        const tingle = swampGuide.toObject().child;
+
+        assert.equal(tingle.name, 'Tingle');
+        assert.equal(tingle.mixedUp, 'very');
+        done();
+      });
     });
+    describe('with the optional subschema behavior (typePojoToMixed=false)', function() {
+      const ParentSchema = new mongoose.Schema(ParentSchemaDef, {typePojoToMixed: false});
+      it('interprets the POJO as a subschema (gh-7494)', function(done) {
+        assert.equal(ParentSchema.paths.child.instance, 'Embedded');
+        assert.equal(ParentSchema.paths.child['$isSingleNested'], true);
+        done();
+      });
+      it('enforces provided schema on the child path, unlike Mixed (gh-7494)', function(done) {
+        const ParentModel = mongoose.model('ParentModel-7494-EmbeddedDeclarativeSubschema', ParentSchema);
+        const kingDaphnes = new ParentModel({
+          name: 'King Daphnes Nohansen Hyrule',
+          child: {
+            name: 'Princess Zelda',
+            mixedUp: 'not',
+          }
+        });
+        const princessZelda = kingDaphnes.child.toObject();
 
-    mongoose.model('Parent-7494-EmbeddedDeclarative', ParentSchema);
+        assert.equal(princessZelda.name, 'Princess Zelda');
+        assert.equal(princessZelda.mixedUp, undefined);
+        done();
+      });
+    });
   });
-
-  it('returns a proper ownerDocument (gh-7494)', function(done) {
-    const Parent = mongoose.model('Parent-7494-EmbeddedDeclarative');
-    const p = new Parent({
-      name: 'Parent Parentson',
+  describe('with a parent with a POJO field with a field "type" with a type set to "String"', function() {
+    const ParentSchemaDef = {
+      name: String,
       child: {
-        name: 'Child Parentson',
-        children: [
-          {
-            name: 'GrandChild Parentson'
-          }
-        ]
+        name: String,
+        type: {
+          type: String,
+        },
       }
+    };
+    const ParentSchemaNotMixed = new Schema(ParentSchemaDef);
+    const ParentSchemaNotSubdoc = new Schema(ParentSchemaDef, {typePojoToMixed: false});
+    it('does not create a path for child in either option', function(done) {
+      assert.equal(ParentSchemaNotMixed.paths['child.name'].instance, 'String');
+      assert.equal(ParentSchemaNotSubdoc.paths['child.name'].instance, 'String');
+      done();
+    });
+    it('treats type as a property name not a type in both options', function(done) {
+      assert.equal(ParentSchemaNotMixed.paths['child.type'].instance, 'String');
+      assert.equal(ParentSchemaNotSubdoc.paths['child.type'].instance, 'String');
+      done();
     });
+    it('enforces provided schema on the child tree in both options, unlike Mixed (gh-7494)', function(done) {
+      const ParentModelNotMixed = mongoose.model('ParentModel-7494-EmbeddedDeclarativeNestedNotMixed', ParentSchemaNotMixed);
+      const ParentModelNotSubdoc = mongoose.model('ParentModel-7494-EmbeddedDeclarativeNestedNotSubdoc', ParentSchemaNotSubdoc);
 
-    assert.equal(p._id, p.child.children[0].ownerDocument()._id);
-    done();
+      const grandmother = new ParentModelNotMixed({
+        name: 'Grandmother',
+        child: {
+          name: 'Rito Chieftan',
+          type: 'Mother',
+          confidence: 10,
+        }
+      });
+      const ritoChieftan = new ParentModelNotSubdoc({
+        name: 'Rito Chieftan',
+        child: {
+          name: 'Prince Komali',
+          type: 'Medli',
+          confidence: 0,
+        }
+      });
+
+      assert.equal(grandmother.child.name, 'Rito Chieftan');
+      assert.equal(grandmother.child.type, 'Mother');
+      assert.equal(grandmother.child.confidence, undefined);
+      assert.equal(ritoChieftan.child.name, 'Prince Komali');
+      assert.equal(ritoChieftan.child.type, 'Medli');
+      assert.equal(ritoChieftan.child.confidence, undefined);
+      done();
+    });
   });
 });

From dd132da0b3867ee658b74a7113cf5d8cbf08ea09 Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Thu, 10 Oct 2019 04:55:33 +0300
Subject: [PATCH 0060/2348] feat(mongoose): allow setting Schema option
 typePojoToMixed mongoosewide

---
 lib/index.js  | 1 +
 lib/schema.js | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index ad89dffc536..6c27bfd1525 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -157,6 +157,7 @@ Mongoose.prototype.driver = require('./driver');
  * - 'toJSON': `{ transform: true, flattenDecimals: true }` by default. Overwrites default objects to [`toJSON()`](/docs/api.html#document_Document-toJSON), for determining how Mongoose documents get serialized by `JSON.stringify()`
  * - 'strict': true by default, may be `false`, `true`, or `'throw'`. Sets the default strict mode for schemas.
  * - 'selectPopulatedPaths': true by default. Set to false to opt out of Mongoose adding all fields that you `populate()` to your `select()`. The schema-level option `selectPopulatedPaths` overwrites this one.
+ * - 'typePojoToMixed': true by default, may be `false` or `true`. Sets the default typePojoToMixed for schemas.
  * - 'maxTimeMS': If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query
  * - 'autoIndex': true by default. Set to false to disable automatic index creation for all models associated with this Mongoose instance.
  *
diff --git a/lib/schema.js b/lib/schema.js
index 8015554c1c7..a6a1de5734a 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -62,7 +62,7 @@ let id = 0;
  * - [toJSON](/docs/guide.html#toJSON) - object - no default
  * - [toObject](/docs/guide.html#toObject) - object - no default
  * - [typeKey](/docs/guide.html#typeKey) - string - defaults to 'type'
- * - [typePojoToMixed](/docs/guide.html#typePojoToMixed) - boolean - defaults to true
+ * - [typePojoToMixed](/docs/guide.html#typePojoToMixed) - boolean - defaults to true. Determines whether a type set to a POJO becomes a Mixed path or a Subdocument
  * - [useNestedStrict](/docs/guide.html#useNestedStrict) - boolean - defaults to false
  * - [validateBeforeSave](/docs/guide.html#validateBeforeSave) - bool - defaults to `true`
  * - [versionKey](/docs/guide.html#versionKey): string - defaults to "__v"
@@ -365,7 +365,7 @@ Schema.prototype.defaultOptions = function(options) {
     noVirtualId: false, // deprecated, use { id: false }
     id: true,
     typeKey: 'type',
-    typePojoToMixed: true
+    typePojoToMixed: 'typePojoToMixed' in baseOptions ? baseOptions.typePojoToMixed : true
   }, utils.clone(options));
 
   if (options.read) {

From 5db570708bf369fbc6dddc09a6149927fdd8334c Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Thu, 10 Oct 2019 05:18:52 +0300
Subject: [PATCH 0061/2348] test(schema): apply more defensive assertions for
 declarative subdocs

---
 test/types.embeddeddocumentdeclarative.test.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
index 4d16d5c3224..092c52e72de 100644
--- a/test/types.embeddeddocumentdeclarative.test.js
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -53,7 +53,7 @@ describe('types.embeddeddocumentdeclarative', function() {
       const ParentSchema = new mongoose.Schema(ParentSchemaDef, {typePojoToMixed: false});
       it('interprets the POJO as a subschema (gh-7494)', function(done) {
         assert.equal(ParentSchema.paths.child.instance, 'Embedded');
-        assert.equal(ParentSchema.paths.child['$isSingleNested'], true);
+        assert.strictEqual(ParentSchema.paths.child['$isSingleNested'], true);
         done();
       });
       it('enforces provided schema on the child path, unlike Mixed (gh-7494)', function(done) {
@@ -68,7 +68,7 @@ describe('types.embeddeddocumentdeclarative', function() {
         const princessZelda = kingDaphnes.child.toObject();
 
         assert.equal(princessZelda.name, 'Princess Zelda');
-        assert.equal(princessZelda.mixedUp, undefined);
+        assert.strictEqual(princessZelda.mixedUp, undefined);
         done();
       });
     });
@@ -112,16 +112,16 @@ describe('types.embeddeddocumentdeclarative', function() {
         child: {
           name: 'Prince Komali',
           type: 'Medli',
-          confidence: 0,
+          confidence: 1,
         }
       });
 
       assert.equal(grandmother.child.name, 'Rito Chieftan');
       assert.equal(grandmother.child.type, 'Mother');
-      assert.equal(grandmother.child.confidence, undefined);
+      assert.strictEqual(grandmother.child.confidence, undefined);
       assert.equal(ritoChieftan.child.name, 'Prince Komali');
       assert.equal(ritoChieftan.child.type, 'Medli');
-      assert.equal(ritoChieftan.child.confidence, undefined);
+      assert.strictEqual(ritoChieftan.child.confidence, undefined);
       done();
     });
   });

From 6a15987213f95d8a274113a78932f5c277101b5a Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Thu, 10 Oct 2019 06:01:15 +0300
Subject: [PATCH 0062/2348] doc(subdocs): document subdocuments, Mixed, and
 typePojoToMixed

---
 docs/guide.pug       | 20 ++++++++++++++++----
 docs/schematypes.pug | 16 +++++++++++++---
 docs/subdocs.pug     | 29 +++++++++++++++++++++++++++--
 3 files changed, 56 insertions(+), 9 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index d4c5927017e..87901d31704 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -47,7 +47,7 @@ block content
       var Schema = mongoose.Schema;
 
       var blogSchema = new Schema({
-        title:  String,
+        title:  String, // String is shorthand for {type: String}
         author: String,
         body:   String,
         comments: [{ body: String, date: Date }],
@@ -67,9 +67,21 @@ block content
     will be cast to its associated [SchemaType](./api.html#schematype_SchemaType).
     For example, we've defined a property `title` which will be cast to the
     [String](./api.html#schema-string-js) SchemaType and property `date`
-    which will be cast to a `Date` SchemaType. Keys may also be assigned
-    nested objects containing further key/type definitions like
-    the `meta` property above.
+    which will be cast to a `Date` SchemaType.
+
+    Notice above that if a property only requires a type, it can be specified using
+    a shorthand notation (contrast the `title` property above with the `date`
+    property).
+    
+    Keys may also be assigned nested objects containing further key/type definitions
+    like the `meta` property above.  This will happen whenever a key's value is a POJO
+    that lacks a bona-fide `type` property.  In these cases, only the leaves in a tree
+    are given actual paths in the schema (like `meta.votes` and `meta.favs` above),
+    and the branches do not have actual paths.  A side-effect of this is that `meta`
+    above cannot have its own validation.  If validation is needed up the tree, a path
+    needs to be created up the tree - see the [Subdocuments](./subdocs.html) section
+    for more information no how to do this.  Also read the [Mixed](./schematypes.html)
+    subsection of the SchemaTypes guide for some gotchas.
 
     The permitted SchemaTypes are:
 
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index ade9a47a067..f07a090f174 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -335,20 +335,30 @@ block content
     const Any = new Schema({ any: Object });
     const Any = new Schema({ any: Schema.Types.Mixed });
     const Any = new Schema({ any: mongoose.Mixed });
-    // Note that if you're using `type`, putting _any_ POJO as the `type` will
+    // Note that by default, if you're using `type`, putting _any_ POJO as the `type` will
     // make the path mixed.
     const Any = new Schema({
       any: {
         type: { foo: String }
-      }
+      } // "any" will be Mixed - everything inside is ignored.
     });
+    // However, as of Mongoose 5.8.0, this behavior can be overridden with typePojoToMixed.
+    // In that case, it will create a single nested subdocument type instead.
+    const Any = new Schema({
+      any: {
+        type: { foo: String }
+      } // "any" will be a single nested subdocument.
+    }, {typePojoToMixed: false});
     ```
 
-    Since it is a schema-less type, you can change the value to anything else you
+    Since Mixed is a schema-less type, you can change the value to anything else you
     like, but Mongoose loses the ability to auto detect and save those changes.
     To tell Mongoose that the value of a Mixed type has changed, you need to
     call `doc.markModified(path)`, passing the path to the Mixed type you just changed.
 
+    To avoid these side-effects, a [Subdocument](./subdocs.html) path may be used
+    instead.
+
     ```javascript
     person.anything = { x: [3, 4, { y: "changed" }] };
     person.markModified('anything');
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index ba98977538e..cec31d3c16b 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -33,6 +33,10 @@ block content
       child: childSchema
     });
     ```
+    Aside from code reuse, one important reason to use subdocuments is to create
+    a path where there would otherwise not be one to allow for validation over
+    a group of fields (e.g. dateRange.fromDate <= dateRange.toDate).
+
   :markdown
     <ul class="toc">
       <li><a href="#what-is-a-subdocument-">What is a Subdocument?</a></li>
@@ -40,7 +44,8 @@ block content
       <li><a href="#adding-subdocs-to-arrays">Adding Subdocs to Arrays</a></li>
       <li><a href="#removing-subdocs">Removing Subdocs</a></li>
       <li><a href="#subdoc-parents">Parents of Subdocs</a></li>
-      <li><a href="#altsyntax">Alternate declaration syntax for arrays</a></li>
+      <li><a href="#altsyntaxarrays">Alternate declaration syntax for arrays</a></li>
+      <li><a href="#altsyntaxsingle">Alternate declaration syntax for single subdocuments</a></li>
     </ul>
 
     ### What is a Subdocument?
@@ -211,7 +216,7 @@ block content
     doc.level1.level2.ownerDocument() === doc; // true
     ```
 
-  h4#altsyntax Alternate declaration syntax for arrays
+  h4#altsyntaxarrays Alternate declaration syntax for arrays
   :markdown
     If you create a schema with an array of objects, mongoose will automatically
     convert the object to a schema for you:
@@ -224,6 +229,26 @@ block content
       children: [new Schema({ name: 'string' })]
     });
     ```
+
+  h4#altsyntaxsingle Alternate declaration syntax for single subdocuments
+  :markdown
+    Similarly, single subdocuments also have a shorthand whereby you can omit
+    wrapping the schema with an instance of Schema.  However, for historical
+    reasons, this alternate declaration must be enabled via an option (either
+    on the parent schema instantiation or on the mongoose instance).
+    ```javascript
+    var parentSchema = new Schema({
+      child: { type: { name: 'string' } }
+    }, { typePojoToMixed: false });
+    // Equivalent
+    var parentSchema = new Schema({
+      child: new Schema({ name: 'string' })
+    });
+    // Not equivalent!  Careful - a Mixed path is created instead!
+    var parentSchema = new Schema({
+      child: { type: { name: 'string' } }
+    });
+    ```
   h3#next Next Up
   :markdown
     Now that we've covered Subdocuments, let's take a look at

From 0562ca7874c8007d9931c7e1ef1745fb4fb04ea7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Oct 2019 14:14:53 -0400
Subject: [PATCH 0063/2348] chore: add opencollective sponsors: top web design
 companies, casino top

---
 index.pug | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/index.pug b/index.pug
index 0597724edf4..a3cb6ce927e 100644
--- a/index.pug
+++ b/index.pug
@@ -223,6 +223,15 @@ html(lang='en')
               <a href="https://vpngorilla.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vpngorilla-com/ae76cc5/logo.png" style="height: 100px">
               </a>
+              <a href="https://medium.com/@niksundin/best-web-design-companies-1872e445775f">
+                <img class="sponsor" src="https://images.opencollective.com/top-web-design-agencies/d92d747/logo.png" style="height: 100px">
+              </a>
+              <a href="https://www.casinotop.com">
+                <img class="sponsor" src="https://images.opencollective.com/casinotop-com/10fd95b/logo.png" style="height: 100px">
+              </a>
+              <a href="https://www.casinotopp.net">
+                <img class="sponsor" src="https://images.opencollective.com/casino-topp/1dd399a/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From ffbff22d127fdd44d4469d6f25bb0c7ea2d930d9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Oct 2019 14:15:15 -0400
Subject: [PATCH 0064/2348] chore: change version for recompiling website

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 11dada08bf3..b7086610300 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.5-pre",
+  "version": "5.7.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 89eb4499634a64de6e15678c07ecdc13db65c45b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Oct 2019 14:20:33 -0400
Subject: [PATCH 0065/2348] chore: now working on 5.7.5

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index b7086610300..11dada08bf3 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.4",
+  "version": "5.7.5-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 54db026004bf777abf18109ed0cdf888c811a38c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Oct 2019 11:02:12 -0400
Subject: [PATCH 0066/2348] test(subdocument): repro #8223

---
 test/types.subdocument.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/types.subdocument.test.js b/test/types.subdocument.test.js
index 5b4cc2bda18..43747660885 100644
--- a/test/types.subdocument.test.js
+++ b/test/types.subdocument.test.js
@@ -92,4 +92,16 @@ describe('types.subdocument', function() {
         }, {$set: thingy2});
       });
   });
+
+  describe('#isModified', function() {
+    it('defers to parent isModified (gh-8223)', function() {
+      const childSchema = Schema({ id: Number, text: String });
+      const parentSchema = Schema({ child: childSchema });
+      const Model = db.model('gh8223', parentSchema);
+
+      const doc = new Model({ child: { text: 'foo' } });
+      assert.ok(doc.isModified('child.id'));
+      assert.ok(doc.child.isModified('id'));
+    });
+  });
 });

From 327b47a1ee3e65abd2b09ced20d129a2dbd6e8ae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Oct 2019 11:03:13 -0400
Subject: [PATCH 0067/2348] fix(subdocument): make subdocument#isModified use
 parent document's isModified

Fix #8223
---
 lib/types/subdocument.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 92a88489523..cb4db5c1651 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -115,6 +115,16 @@ Subdocument.prototype.markModified = function(path) {
   }
 };
 
+Subdocument.prototype.isModified = function(paths, modifiedPaths) {
+  if (this.$parent && this.$basePath) {
+    paths = (Array.isArray(paths) ? paths : paths.split(' ')).
+      map(p => [this.$basePath, p].join('.'));
+    return this.$parent.isModified(paths, modifiedPaths);
+  }
+
+  return Document.prototype.isModified(paths, modifiedPaths);
+};
+
 /**
  * Marks a path as valid, removing existing validation errors.
  *

From b9c10123dee0ed9dad176b018552bb3004ed2535 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Oct 2019 11:31:44 -0400
Subject: [PATCH 0068/2348] docs(middleware): add note about accessing the
 document being updated in pre('findOneAndUpdate')

Fix #8218
---
 docs/middleware.pug | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index 1b5cf0afd4a..6b326fd4b14 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -360,11 +360,22 @@ block content
     **query** object rather than the document being updated.
 
     For instance, if you wanted to add an `updatedAt` timestamp to every
-    `update()` call, you would use the following pre hook.
+    `updateOne()` call, you would use the following pre hook.
 
     ```javascript
-    schema.pre('update', function() {
-      this.update({},{ $set: { updatedAt: new Date() } });
+    schema.pre('updateOne', function() {
+      this.set({ updatedAt: new Date() });
+    });
+    ```
+
+    You **cannot** access the document being updated in `pre('updateOne')` or
+    `pre('findOneAndUpdate')` middleware. If you need to access the document
+    that will be updated, you need to execute an explicit query for the document.
+
+    ```javascript
+    schema.pre('findOneAndUpdate', async function() {
+      const docToUpdate = await this.model.findOne(this.getQuery());
+      console.log(docToUpdate); // The document that `findOneAndUpdate()` will modify
     });
     ```
 

From 98b3b094edcc22bc73a4df248abf7e53c052d3a8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Oct 2019 11:57:56 -0400
Subject: [PATCH 0069/2348] test(update): repro #7187

---
 test/query.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index ba5bd1efadc..f15cdb07ba0 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3549,6 +3549,24 @@ describe('Query', function() {
         assert.equal(doc.password, 'encryptedpassword');
       });
     });
+
+    it('pre("validate") errors (gh-7187)', function() {
+      const addressSchema = Schema({ countryId: String });
+      addressSchema.pre('validate', { query: true }, function() {
+        throw new Error('Oops!');
+      });
+      const contactSchema = Schema({ addresses: [addressSchema] });
+      const Contact = db.model('gh7187', contactSchema);
+
+      const update = { addresses: [{ countryId: 'foo' }] };
+      return Contact.updateOne({}, update, { runValidators: true }).then(
+        () => assert.ok(false),
+        err => {
+          assert.ok(err.errors['addresses.0']);
+          assert.equal(err.errors['addresses.0'].message, 'Oops!');
+        }
+      );
+    });
   });
 
   it('query with top-level _bsontype (gh-8222)', function() {

From 936ddfb9c68edb44c76fc36cf251415c0828d266 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Oct 2019 12:28:30 -0400
Subject: [PATCH 0070/2348] fix(update): handle subdocument pre('validate')
 errors in update validation

Fix #7187
---
 lib/document.js                 | 8 +++++---
 lib/helpers/updateValidators.js | 3 +++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0183ce47e51..b816b8bde97 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1932,9 +1932,11 @@ Document.prototype.validate = function(options, callback) {
     options = null;
   }
 
-  return utils.promiseOrCallback(callback, cb => this.$__validate(options, function(error) {
-    cb(error);
-  }), this.constructor.events);
+  return utils.promiseOrCallback(callback, cb => {
+    this.$__validate(options, function(error) {
+      cb(error);
+    });
+  }, this.constructor.events);
 };
 
 /*!
diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index 199ef0677f7..de8b027bb9f 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -136,6 +136,9 @@ module.exports = function(query, schema, castedDoc, options, callback) {
                     _err.path = updates[i] + '.' + key;
                     validationErrors.push(_err);
                   }
+                } else {
+                  err.path = updates[i];
+                  validationErrors.push(err);
                 }
               }
               callback(null);

From cdfb507be166e6f047b2a621403e63d93a58d418 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Oct 2019 12:44:43 -0400
Subject: [PATCH 0071/2348] chore: add useUnifiedTopology for tests re: #8212

---
 test/connection.test.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index bddc59ec5f1..89056d5524b 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -188,7 +188,10 @@ describe('connections:', function() {
         let numReconnected = 0;
         let numReconnect = 0;
         let numClose = 0;
-        const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest', { useNewUrlParser: true });
+        const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest', {
+          useNewUrlParser: true,
+          useUnifiedTopology: true
+        });
 
         conn.on('connected', function() {
           ++numConnected;
@@ -255,7 +258,8 @@ describe('connections:', function() {
         const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest', {
           reconnectTries: 3,
           reconnectInterval: 100,
-          useNewUrlParser: true
+          useNewUrlParser: true,
+          useUnifiedTopology: true
         });
 
         conn.on('connected', function() {

From 973b1e07014950b5c7d3f8af5ea9a61f485e1711 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Oct 2019 15:25:18 -0400
Subject: [PATCH 0072/2348] docs: add schema options to API docs

Fix #8012
---
 docs/api.pug                         | 19 +++++++++---------
 docs/api_split.pug                   | 29 ++++++++++++++--------------
 docs/source/api.js                   | 16 ++++++++++++++-
 lib/index.js                         |  9 +++++++++
 lib/options/SchemaArrayOptions.js    | 13 +++++++++++++
 lib/options/SchemaBufferOptions.js   | 13 +++++++++++++
 lib/options/SchemaDateOptions.js     | 13 +++++++++++++
 lib/options/SchemaNumberOptions.js   | 13 +++++++++++++
 lib/options/SchemaObjectIdOptions.js | 13 +++++++++++++
 lib/options/SchemaStringOptions.js   | 13 +++++++++++++
 lib/options/SchemaTypeOptions.js     | 12 ++++++++++++
 lib/schematype.js                    |  2 +-
 12 files changed, 140 insertions(+), 25 deletions(-)

diff --git a/docs/api.pug b/docs/api.pug
index 42c6c5a1376..7644708ca4f 100644
--- a/docs/api.pug
+++ b/docs/api.pug
@@ -16,15 +16,16 @@ block content
   div.api-nav
     div.api-nav-content
       each item in docs
-        div.nav-item(id='nav-' + item.name)
-          div.nav-item-title
-            a(href='./api/' + item.name.toLowerCase() + '.html')
-              | #{item.name}
-          ul.nav-item-sub
-            each prop in item.props
-              li
-                a(href='./api/' + item.name.toLowerCase() + '.html#' + prop.anchorId)
-                  | #{prop.string}
+        - if (!item.hideFromNav)
+          div.nav-item(id='nav-' + item.name)
+            div.nav-item-title
+              a(href='./api/' + item.name.toLowerCase() + '.html')
+                | #{item.name}
+            ul.nav-item-sub
+              each prop in item.props
+                li
+                  a(href='./api/' + item.name.toLowerCase() + '.html#' + prop.anchorId)
+                    | #{prop.string}
 
   each item in docs
     hr.separate-api
diff --git a/docs/api_split.pug b/docs/api_split.pug
index 2ffc93e3608..021ca601bd6 100644
--- a/docs/api_split.pug
+++ b/docs/api_split.pug
@@ -25,20 +25,21 @@ block content
   div.api-nav
     div.api-nav-content
       each item in docs
-        div.nav-item(id='nav-' + item.name)
-          - if (item.name === name)
-            div.nav-item-title(style="font-weight: bold")
-              a(href=item.name.toLowerCase() + '.html')
-                | #{item.name}
-            ul.nav-item-sub
-              each prop in item.props
-                li
-                  a(href='#' + prop.anchorId)
-                    | #{prop.string}
-          - else
-            div.nav-item-title
-              a(href=item.name.toLowerCase() + '.html')
-                | #{item.name}
+        - if (!item.hideFromNav || item.name === name)
+          div.nav-item(id='nav-' + item.name)
+            - if (item.name === name)
+              div.nav-item-title(style="font-weight: bold")
+                a(href=item.name.toLowerCase() + '.html')
+                  | #{item.name}
+              ul.nav-item-sub
+                each prop in item.props
+                  li
+                    a(href='#' + prop.anchorId)
+                      | #{prop.string}
+            - else
+              div.nav-item-title
+                a(href=item.name.toLowerCase() + '.html')
+                  | #{item.name}
 
   div.api-content
     ul
diff --git a/docs/source/api.js b/docs/source/api.js
index 8ef499a6ca3..011ab45fe45 100644
--- a/docs/source/api.js
+++ b/docs/source/api.js
@@ -24,7 +24,14 @@ const files = [
   'lib/virtualtype.js',
   'lib/error/index.js',
   'lib/types/core_array.js',
-  'lib/schema/SingleNestedPath.js'
+  'lib/schema/SingleNestedPath.js',
+  'lib/options/SchemaTypeOptions.js',
+  'lib/options/SchemaArrayOptions.js',
+  'lib/options/SchemaBufferOptions.js',
+  'lib/options/SchemaDateOptions.js',
+  'lib/options/SchemaNumberOptions.js',
+  'lib/options/SchemaObjectIdOptions.js',
+  'lib/options/SchemaStringOptions.js'
 ];
 
 module.exports = {
@@ -83,6 +90,9 @@ function parse() {
             ctx.name = str;
             ctx.string = `${ctx.constructor}.prototype.${ctx.name}`;
             break;
+          case 'type':
+            ctx.type = Array.isArray(tag.types) ? tag.types.join('|') : tag.types;
+            break;
           case 'static':
             ctx.type = 'property';
             ctx.static = true;
@@ -164,6 +174,10 @@ function parse() {
       }
     });
 
+    if (props.file.startsWith('lib/options')) {
+      data.hideFromNav = true;
+    }
+
     out.push(data);
   }
 }
diff --git a/lib/index.js b/lib/index.js
index ad89dffc536..6fbfb932e5c 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -1015,6 +1015,15 @@ Mongoose.prototype.now = function now() { return new Date(); };
 
 Mongoose.prototype.CastError = require('./error/cast');
 
+/**
+ * The constructor used for schematype options
+ *
+ * @method SchemaTypeOptions
+ * @api public
+ */
+
+Mongoose.prototype.SchemaTypeOptions = require('./options/SchemaTypeOptions');
+
 /**
  * The [node-mongodb-native](https://github.com/mongodb/node-mongodb-native) driver Mongoose uses.
  *
diff --git a/lib/options/SchemaArrayOptions.js b/lib/options/SchemaArrayOptions.js
index 330ac2db5e9..5ad6fe9060a 100644
--- a/lib/options/SchemaArrayOptions.js
+++ b/lib/options/SchemaArrayOptions.js
@@ -2,6 +2,19 @@
 
 const SchemaTypeOptions = require('./SchemaTypeOptions');
 
+/**
+ * The options defined on an Array schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ tags: [String] });
+ *     schema.path('tags').options; // SchemaArrayOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaArrayOptions
+ */
+
 class SchemaArrayOptions extends SchemaTypeOptions {}
 
 const opts = {
diff --git a/lib/options/SchemaBufferOptions.js b/lib/options/SchemaBufferOptions.js
index 4ee8957ba2a..d5cb9bda23c 100644
--- a/lib/options/SchemaBufferOptions.js
+++ b/lib/options/SchemaBufferOptions.js
@@ -2,6 +2,19 @@
 
 const SchemaTypeOptions = require('./SchemaTypeOptions');
 
+/**
+ * The options defined on a Buffer schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ bitmap: Buffer });
+ *     schema.path('bitmap').options; // SchemaBufferOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaBufferOptions
+ */
+
 class SchemaBufferOptions extends SchemaTypeOptions {}
 
 const opts = {
diff --git a/lib/options/SchemaDateOptions.js b/lib/options/SchemaDateOptions.js
index 5334e5f66c3..5a78ea44aeb 100644
--- a/lib/options/SchemaDateOptions.js
+++ b/lib/options/SchemaDateOptions.js
@@ -2,6 +2,19 @@
 
 const SchemaTypeOptions = require('./SchemaTypeOptions');
 
+/**
+ * The options defined on a Date schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ startedAt: Date });
+ *     schema.path('startedAt').options; // SchemaDateOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaDateOptions
+ */
+
 class SchemaDateOptions extends SchemaTypeOptions {}
 
 const opts = {
diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index 6bb57e3cd98..4b016bebd0d 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -2,6 +2,19 @@
 
 const SchemaTypeOptions = require('./SchemaTypeOptions');
 
+/**
+ * The options defined on a Number schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ count: Number });
+ *     schema.path('count').options; // SchemaNumberOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaNumberOptions
+ */
+
 class SchemaNumberOptions extends SchemaTypeOptions {}
 
 const opts = {
diff --git a/lib/options/SchemaObjectIdOptions.js b/lib/options/SchemaObjectIdOptions.js
index 67ecc8a863d..948116e04ae 100644
--- a/lib/options/SchemaObjectIdOptions.js
+++ b/lib/options/SchemaObjectIdOptions.js
@@ -2,6 +2,19 @@
 
 const SchemaTypeOptions = require('./SchemaTypeOptions');
 
+/**
+ * The options defined on an ObjectId schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ testId: mongoose.ObjectId });
+ *     schema.path('testId').options; // SchemaObjectIdOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaObjectIdOptions
+ */
+
 class SchemaObjectIdOptions extends SchemaTypeOptions {}
 
 const opts = {
diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index 54ca35edfba..72271828224 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -2,6 +2,19 @@
 
 const SchemaTypeOptions = require('./SchemaTypeOptions');
 
+/**
+ * The options defined on a string schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ name: String });
+ *     schema.path('name').options; // SchemaStringOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaStringOptions
+ */
+
 class SchemaStringOptions extends SchemaTypeOptions {}
 
 const opts = {
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 51bfd6b571b..6b7444f1333 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -2,6 +2,18 @@
 
 const utils = require('../utils');
 
+/**
+ * The options defined on a schematype.
+ *
+ * ####Example:
+ * 
+ *     const schema = new Schema({ name: String });
+ *     schema.path('name').options instanceof mongoose.SchemaTypeOptions; // true
+ *
+ * @api public
+ * @constructor SchemaTypeOptions
+ */
+
 class SchemaTypeOptions {
   constructor(obj) {
     if (obj == null) {
diff --git a/lib/schematype.js b/lib/schematype.js
index fbce0e0dce6..ed5b6738ec0 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -29,7 +29,7 @@ const ValidatorError = MongooseError.ValidatorError;
  *     schema.path('name') instanceof SchemaType; // true
  *
  * @param {String} path
- * @param {Object} [options]
+ * @param {SchemaTypeOptions} [options] See [SchemaTypeOptions docs](/docs/api/schematypeoptions.html)
  * @param {String} [instance]
  * @api public
  */

From 96ce0eb009a2309fc04f1ec0617dc0c49468ca05 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Oct 2019 15:28:24 -0400
Subject: [PATCH 0073/2348] style: fix lint

---
 lib/options/SchemaArrayOptions.js    | 2 +-
 lib/options/SchemaBufferOptions.js   | 2 +-
 lib/options/SchemaDateOptions.js     | 2 +-
 lib/options/SchemaNumberOptions.js   | 2 +-
 lib/options/SchemaObjectIdOptions.js | 2 +-
 lib/options/SchemaStringOptions.js   | 2 +-
 lib/options/SchemaTypeOptions.js     | 2 +-
 7 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/options/SchemaArrayOptions.js b/lib/options/SchemaArrayOptions.js
index 5ad6fe9060a..74c39f69098 100644
--- a/lib/options/SchemaArrayOptions.js
+++ b/lib/options/SchemaArrayOptions.js
@@ -6,7 +6,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
  * The options defined on an Array schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ tags: [String] });
  *     schema.path('tags').options; // SchemaArrayOptions instance
  *
diff --git a/lib/options/SchemaBufferOptions.js b/lib/options/SchemaBufferOptions.js
index d5cb9bda23c..96577b989e2 100644
--- a/lib/options/SchemaBufferOptions.js
+++ b/lib/options/SchemaBufferOptions.js
@@ -6,7 +6,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
  * The options defined on a Buffer schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ bitmap: Buffer });
  *     schema.path('bitmap').options; // SchemaBufferOptions instance
  *
diff --git a/lib/options/SchemaDateOptions.js b/lib/options/SchemaDateOptions.js
index 5a78ea44aeb..5a88a77a8c2 100644
--- a/lib/options/SchemaDateOptions.js
+++ b/lib/options/SchemaDateOptions.js
@@ -6,7 +6,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
  * The options defined on a Date schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ startedAt: Date });
  *     schema.path('startedAt').options; // SchemaDateOptions instance
  *
diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index 4b016bebd0d..6260ea74a10 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -6,7 +6,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
  * The options defined on a Number schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ count: Number });
  *     schema.path('count').options; // SchemaNumberOptions instance
  *
diff --git a/lib/options/SchemaObjectIdOptions.js b/lib/options/SchemaObjectIdOptions.js
index 948116e04ae..440701cea31 100644
--- a/lib/options/SchemaObjectIdOptions.js
+++ b/lib/options/SchemaObjectIdOptions.js
@@ -6,7 +6,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
  * The options defined on an ObjectId schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ testId: mongoose.ObjectId });
  *     schema.path('testId').options; // SchemaObjectIdOptions instance
  *
diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index 72271828224..11e8848a787 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -6,7 +6,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
  * The options defined on a string schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ name: String });
  *     schema.path('name').options; // SchemaStringOptions instance
  *
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 6b7444f1333..3dfff15665e 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -6,7 +6,7 @@ const utils = require('../utils');
  * The options defined on a schematype.
  *
  * ####Example:
- * 
+ *
  *     const schema = new Schema({ name: String });
  *     schema.path('name').options instanceof mongoose.SchemaTypeOptions; // true
  *

From 13ae085a9878b4fce67cede1b2e3fddd84768b8a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Oct 2019 15:43:26 -0400
Subject: [PATCH 0074/2348] docs(index): add favicon to home page

Fix #8226
---
 index.pug | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/index.pug b/index.pug
index a3cb6ce927e..81649be961a 100644
--- a/index.pug
+++ b/index.pug
@@ -9,6 +9,24 @@ html(lang='en')
     link(href="docs/css/style.css", rel="stylesheet")
     link(href="/docs/css/github.css", rel="stylesheet")
 
+    link(rel='apple-touch-icon', sizes='57x57', href='docs/images/favicon/apple-icon-57x57.png')
+    link(rel='apple-touch-icon', sizes='60x60', href='docs/images/favicon/apple-icon-60x60.png')
+    link(rel='apple-touch-icon', sizes='72x72', href='docs/images/favicon/apple-icon-72x72.png')
+    link(rel='apple-touch-icon', sizes='76x76', href='docs/images/favicon/apple-icon-76x76.png')
+    link(rel='apple-touch-icon', sizes='114x114', href='docs/images/favicon/apple-icon-114x114.png')
+    link(rel='apple-touch-icon', sizes='120x120', href='docs/images/favicon/apple-icon-120x120.png')
+    link(rel='apple-touch-icon', sizes='144x144', href='docs/images/favicon/apple-icon-144x144.png')
+    link(rel='apple-touch-icon', sizes='152x152', href='docs/images/favicon/apple-icon-152x152.png')
+    link(rel='apple-touch-icon', sizes='180x180', href='docs/images/favicon/apple-icon-180x180.png')
+    link(rel='icon', type='image/png', sizes='192x192',  href='docs/images/favicon/android-icon-192x192.png')
+    link(rel='icon', type='image/png', sizes='32x32', href='docs/images/favicon/favicon-32x32.png')
+    link(rel='icon', type='image/png', sizes='96x96', href='docs/images/favicon/favicon-96x96.png')
+    link(rel='icon', type='image/png', sizes='16x16', href='docs/images/favicon/favicon-16x16.png')
+    link(rel='manifest', href='docs/images/favicon/manifest.json')
+    meta(name='msapplication-TileColor', content='#ffffff')
+    meta(name='msapplication-TileImage', content='docs/images/favicon/ms-icon-144x144.png')
+    meta(name='theme-color', content='#ffffff')
+
     style.
       code {
         font-size: 1em;

From 30a50f28b63b60f9c40059bb1d0fa258cbd44694 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Oct 2019 16:33:24 -0400
Subject: [PATCH 0075/2348] feat(update): basic support for update pipelines in
 MongoDB 4.2

Re: #8225
---
 lib/helpers/query/castUpdate.js | 32 ++++++++++++++++++++++++++++++--
 lib/query.js                    | 22 ++++++++++++++++++++--
 test/model.update.test.js       | 28 ++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 37a53b5a7e6..d4c49ac6b88 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -22,9 +22,20 @@ const utils = require('../../utils');
  */
 
 module.exports = function castUpdate(schema, obj, options, context, filter) {
-  if (!obj) {
+  if (obj == null) {
     return undefined;
   }
+  options = options || {};
+
+  // Update pipeline
+  if (Array.isArray(obj)) {
+    const len = obj.length;
+    options.pipeline = true;
+    for (let i = 0; i < len; ++i) {
+      obj[i] = castUpdate(schema, obj[i], options, context, filter);
+    }
+    return obj;
+  }
 
   const ops = Object.keys(obj);
   let i = ops.length;
@@ -74,7 +85,10 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
     val = ret[op];
     hasDollarKey = hasDollarKey || op.startsWith('$');
 
-    if (val &&
+    if (op === '$unset' && options.pipeline) {
+      hasKeys = true;
+      castPipelineOperator(op, val);
+    } else if (val &&
         typeof val === 'object' &&
         !Buffer.isBuffer(val) &&
         (!overwrite || hasDollarKey)) {
@@ -101,6 +115,20 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
   return hasKeys && ret;
 };
 
+/*!
+ * ignore
+ */
+
+function castPipelineOperator(op, val) {
+  if (op === '$unset') {
+    if (!Array.isArray(val) || val.find(v => typeof v !== 'string')) {
+      throw new Error('Invalid $unset in pipeline, must be an array of strings');
+    }
+  }
+
+  return val;
+}
+
 /*!
  * Walk each path of obj and cast its values
  * according to its schema.
diff --git a/lib/query.js b/lib/query.js
index 714ceb38c54..adb5d13f048 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3599,12 +3599,29 @@ const _legacyFindAndModify = util.deprecate(function(filter, update, opts, cb) {
  */
 
 Query.prototype._mergeUpdate = function(doc) {
-  if (!this._update) this._update = {};
+  if (doc == null || (typeof doc === 'object' && Object.keys(doc).length === 0)) {
+    return;
+  }
+
+  if (!this._update) {
+    this._update = Array.isArray(doc) ? [] : {};
+  }
   if (doc instanceof Query) {
+    if (Array.isArray(this._update)) {
+      throw new Error('Cannot mix array and object updates');
+    }
     if (doc._update) {
       utils.mergeClone(this._update, doc._update);
     }
+  } else if (Array.isArray(doc)) {
+    if (!Array.isArray(this._update)) {
+      throw new Error('Cannot mix array and object updates');
+    }
+    this._update = this._update.concat(doc);
   } else {
+    if (Array.isArray(this._update)) {
+      throw new Error('Cannot mix array and object updates');
+    }
     utils.mergeClone(this._update, doc);
   }
 };
@@ -3654,6 +3671,7 @@ function _updateThunk(op, callback) {
 
   ++this._executionCount;
 
+  console.log('FT', this._update)
   this._update = utils.clone(this._update, options);
   const isOverwriting = this.options.overwrite && !hasDollarKeys(this._update);
   if (isOverwriting) {
@@ -4153,7 +4171,7 @@ function _update(query, op, filter, doc, options, callback) {
     return query;
   }
 
-  return Query.base[op].call(query, filter, doc, options, callback);
+  return Query.base[op].call(query, filter, void 0, options, callback);
 }
 
 /**
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 961409fbb08..95b1c4b7623 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3382,4 +3382,32 @@ describe('model: updateOne: ', function() {
       assert.equal(updatedDoc.slides[0].commonField, 'newValue2');
     });
   });
+
+  describe('mongodb 42 features', function() {
+    before(function(done) {
+      start.mongodVersion((err, version) => {
+        assert.ifError(err);
+        if (version[0] < 4 || (version[0] === 4 && version[1] < 2)) {
+          this.skip();
+        }
+        done();
+      });
+    });
+
+    it('update pipeline (gh-8225)', function() {
+      const schema = Schema({ oldProp: String, newProp: String });
+      const Model = db.model('gh8225', schema);
+
+      return co(function*() {
+        yield Model.create({ oldProp: 'test' });
+        yield Model.updateOne({}, [
+          { $set: { newProp: 'test2' } },
+          { $unset: ['oldProp'] }
+        ]);
+        const doc = yield Model.findOne();
+        assert.equal(doc.newProp, 'test2');
+        assert.strictEqual(doc.oldProp, void 0);
+      });
+    });
+  });
 });
\ No newline at end of file

From cec9ddaf4a1180b0b9730e5351b285a18d873768 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 13 Oct 2019 14:09:21 +0200
Subject: [PATCH 0076/2348] Minor refactor to ValidationError

---
 lib/error/validation.js | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/error/validation.js b/lib/error/validation.js
index 85b733c48b3..fb251bd94f1 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -17,20 +17,23 @@ const util = require('util');
 
 function ValidationError(instance) {
   this.errors = {};
+  this.name = 'ValidationError';
   this._message = '';
+
   if (instance && instance.constructor.name === 'model') {
     this._message = instance.constructor.modelName + ' validation failed';
-    MongooseError.call(this, this._message);
   } else {
     this._message = 'Validation failed';
-    MongooseError.call(this, this._message);
   }
-  this.name = 'ValidationError';
+
+  MongooseError.call(this, this._message);
+
   if (Error.captureStackTrace) {
     Error.captureStackTrace(this);
   } else {
     this.stack = new Error().stack;
   }
+
   if (instance) {
     instance.errors = this.errors;
   }

From d9163f561311642e36c79be4d40d396efe3f40af Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Oct 2019 09:58:36 -0400
Subject: [PATCH 0077/2348] fix: correct order for declaration

---
 lib/error/validation.js | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/error/validation.js b/lib/error/validation.js
index fb251bd94f1..950513575ed 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -17,16 +17,15 @@ const util = require('util');
 
 function ValidationError(instance) {
   this.errors = {};
-  this.name = 'ValidationError';
   this._message = '';
 
+  MongooseError.call(this, this._message);
   if (instance && instance.constructor.name === 'model') {
     this._message = instance.constructor.modelName + ' validation failed';
   } else {
     this._message = 'Validation failed';
   }
-
-  MongooseError.call(this, this._message);
+  this.name = 'ValidationError';
 
   if (Error.captureStackTrace) {
     Error.captureStackTrace(this);

From 159457db97e55fb59d0c632be59ef5d97fa06459 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Oct 2019 10:24:07 -0400
Subject: [PATCH 0078/2348] chore: add vpn black friday as sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 81649be961a..60c29ebcbf5 100644
--- a/index.pug
+++ b/index.pug
@@ -250,6 +250,9 @@ html(lang='en')
               <a href="https://www.casinotopp.net">
                 <img class="sponsor" src="https://images.opencollective.com/casino-topp/1dd399a/logo.png" style="height: 100px">
               </a>
+              <a href="https://vpnblackfriday.com/">
+                <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 40a879b455145c11480493f79790dcf1286306bf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Oct 2019 10:24:24 -0400
Subject: [PATCH 0079/2348] chore: release 5.7.5

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 518e423493b..4542f383577 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.7.5 / 2019-10-14
+==================
+ * fix(query): delete top-level `_bsontype` property in queries to prevent silent empty queries #8222
+ * fix(update): handle subdocument pre('validate') errors in update validation #7187
+ * fix(subdocument): make subdocument#isModified use parent document's isModified #8223
+ * docs(index): add favicon to home page #8226
+ * docs: add schema options to API docs #8012
+ * docs(middleware): add note about accessing the document being updated in pre('findOneAndUpdate') #8218
+ * refactor: remove redundant code in ValidationError #8244 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.7.4 / 2019-10-09
 ==================
  * fix(schema): handle `required: null` and `required: undefined` as `required: false` #8219
diff --git a/package.json b/package.json
index 11dada08bf3..febd762bf1e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.5-pre",
+  "version": "5.7.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From cb014aca3df1564051568ecb1932f22d792b853a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Oct 2019 11:23:33 -0400
Subject: [PATCH 0080/2348] chore: add links to sort and splice tutorials

---
 lib/types/core_array.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index b298acf4664..9f0aa9f5f25 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -723,6 +723,7 @@ class CoreMongooseArray extends Array {
    * @api public
    * @method sort
    * @memberOf MongooseArray
+   * @see https://masteringjs.io/tutorials/fundamentals/array-sort
    */
 
   sort() {
@@ -741,6 +742,7 @@ class CoreMongooseArray extends Array {
    * @api public
    * @method splice
    * @memberOf MongooseArray
+   * @see https://masteringjs.io/tutorials/fundamentals/array-splice
    */
 
   splice() {

From c2a24574dd6f2ac091e82a2f86f1451b63c83054 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Oct 2019 15:03:12 -0400
Subject: [PATCH 0081/2348] chore: add loanscouter as opencollective sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 60c29ebcbf5..4ad2c1a87d5 100644
--- a/index.pug
+++ b/index.pug
@@ -253,6 +253,9 @@ html(lang='en')
               <a href="https://vpnblackfriday.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
               </a>
+              <a href="https://loanscouter.com/">
+                <img class="sponsor" src="https://images.opencollective.com/lead-supply/7400b71/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 5176c2998db4459a7547e9b887adc4d6d1c6fc8e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Oct 2019 11:38:24 -0400
Subject: [PATCH 0082/2348] fix: bump mongodb driver -> 3.3.3

Fix #8209
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index febd762bf1e..66547f6eb5d 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.3.2",
+    "mongodb": "3.3.3",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From 8b4bcd0c330e1be4a2954d07b2dbb5428036dc6e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Oct 2019 11:44:39 -0400
Subject: [PATCH 0083/2348] test: remove flakey test re: #8209

---
 test/connection.test.js | 27 ---------------------------
 1 file changed, 27 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index 89056d5524b..0126d7f6ded 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1074,33 +1074,6 @@ describe('connections:', function() {
           done();
         });
       });
-      describe('when only username is defined', function() {
-        let listeners;
-
-        beforeEach(function() {
-          listeners = process.listeners('uncaughtException');
-          process.removeAllListeners('uncaughtException');
-        });
-
-        afterEach(function() {
-          process.on('uncaughtException', listeners[0]);
-        });
-
-        it('should return true', function(done) {
-          const db = mongoose.createConnection();
-          db.openUri('mongodb://localhost:27017/fake', {
-            user: 'user'
-          });
-          process.once('uncaughtException', err => {
-            err.uncaught = false;
-            assert.ok(err.message.includes('password must be a string'));
-            done();
-          });
-
-          assert.equal(db.shouldAuthenticate(), true);
-          db.close(done);
-        });
-      });
       describe('when both username and password are defined', function() {
         it('should return true', function(done) {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {

From 258b929e86b5806e7a3b240cbe397753962a9aff Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Oct 2019 12:03:25 -0400
Subject: [PATCH 0084/2348] test(connection): more cleanup re: #8209

---
 test/connection.test.js | 35 -----------------------------------
 1 file changed, 35 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index 0126d7f6ded..c6793e01f0c 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -500,31 +500,6 @@ describe('connections:', function() {
   });
 
   describe('connect callbacks', function() {
-    it('execute with user:pwd connection strings', function(done) {
-      const db = mongoose.createConnection('mongodb://aaron:psw@localhost:27000/fake', { useNewUrlParser: true }, function() {
-        done();
-      });
-      db.catch(() => {});
-      db.on('error', function(err) {
-        assert.ok(err);
-      });
-      db.close();
-    });
-    it('execute without user:pwd connection strings', function(done) {
-      const db = mongoose.createConnection('mongodb://localhost/fake', { useNewUrlParser: true }, function() {
-      });
-      db.on('error', function(err) {
-        assert.ok(err);
-      });
-      assert.equal(typeof db.options, 'object');
-      assert.equal(db.user, undefined);
-      assert.equal(db.name, 'fake');
-      assert.equal(db.host, 'localhost');
-      assert.equal(db.port, 27017);
-      db.close();
-      setTimeout(done, 10);
-    });
-
     it('should return an error if malformed uri passed', function(done) {
       const db = mongoose.createConnection('mongodb:///fake', { useNewUrlParser: true }, function(err) {
         assert.ok(/hostname/.test(err.message));
@@ -533,16 +508,6 @@ describe('connections:', function() {
       db.close();
       assert.ok(!db.options);
     });
-    it('should use admin db if not specified and user/pass specified', function(done) {
-      const db = mongoose.createConnection('mongodb://u:p@localhost/admin', { useNewUrlParser: true }, function() {
-        done();
-      });
-      assert.equal(typeof db.options, 'object');
-      assert.equal(db.name, 'admin');
-      assert.equal(db.host, 'localhost');
-      assert.equal(db.port, 27017);
-      db.close();
-    });
   });
 
   describe('errors', function() {

From e93501eb5c7ce0191bcb3d9e85d9290c679a3f00 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Oct 2019 12:29:25 -0400
Subject: [PATCH 0085/2348] test(connection): work around NODE-2250 for now re:
 #8209

---
 test/connection.test.js | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index c6793e01f0c..f982879c61d 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -433,15 +433,16 @@ describe('connections:', function() {
     db.close(done);
   });
 
-  it('should accept mongodb://aaron:psw@localhost:27000/fake', function(done) {
-    const db = mongoose.createConnection('mongodb://aaron:psw@localhost:27000/fake', { useNewUrlParser: true }, () => {
+  it('should accept mongodb://aaron:psw@localhost:27017/fake', function(done) {
+    const opts = { useNewUrlParser: true };
+    const db = mongoose.createConnection('mongodb://aaron:psw@localhost:27017/fake', opts, () => {
       db.close(done);
     });
     assert.equal(db.pass, 'psw');
     assert.equal(db.user, 'aaron');
     assert.equal(db.name, 'fake');
     assert.equal(db.host, 'localhost');
-    assert.equal(db.port, 27000);
+    assert.equal(db.port, 27017);
   });
 
   it('should accept unix domain sockets', function(done) {
@@ -513,7 +514,10 @@ describe('connections:', function() {
   describe('errors', function() {
     it('event fires with one listener', function(done) {
       this.timeout(1500);
-      const db = mongoose.createConnection('mongodb://bad.notadomain/fakeeee?connectTimeoutMS=100');
+      const db = mongoose.createConnection('mongodb://bad.notadomain/fakeeee?connectTimeoutMS=100', {
+        useNewUrlParser: true,
+        useUnifiedTopology: false // Workaround re: NODE-2250
+      });
       db.catch(() => {});
       db.on('error', function() {
         // this callback has no params which triggered the bug #759
@@ -523,7 +527,11 @@ describe('connections:', function() {
     });
 
     it('should occur without hanging when password with special chars is used (gh-460)', function(done) {
-      mongoose.createConnection('mongodb://aaron:ps#w@localhost/fake?connectTimeoutMS=500', function(err) {
+      const opts = {
+        useNewUrlParser: true,
+        useUnifiedTopology: false
+      };
+      mongoose.createConnection('mongodb://aaron:ps#w@localhost/fake?connectTimeoutMS=500', opts, function(err) {
         assert.ok(err);
         done();
       });

From be5e1fa48015acabd4ff7df4906831fe1069f41e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Oct 2019 12:33:11 -0400
Subject: [PATCH 0086/2348] test(connection): more #8209 test cleanup

---
 test/connection.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index f982879c61d..4d97b7caf84 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -434,7 +434,7 @@ describe('connections:', function() {
   });
 
   it('should accept mongodb://aaron:psw@localhost:27017/fake', function(done) {
-    const opts = { useNewUrlParser: true };
+    const opts = { useNewUrlParser: true, useUnifiedTopology: false };
     const db = mongoose.createConnection('mongodb://aaron:psw@localhost:27017/fake', opts, () => {
       db.close(done);
     });

From 27cefad180684ed668ab1096a95db1bc0b4cc30b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Oct 2019 13:51:26 -0400
Subject: [PATCH 0087/2348] fix(connection): ensure repeated `close` events
 from useUnifiedTopology don't disconnect Mongoose from replica set

Fix #8224
Re: NODE-2251
---
 lib/connection.js | 44 ++++++++++++++++++++++++++++----------------
 1 file changed, 28 insertions(+), 16 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 43e4028510b..d3fde9d4c15 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -639,18 +639,28 @@ Connection.prototype.openUri = function(uri, options, callback) {
       _this.db = db;
 
       // `useUnifiedTopology` events
-      if (options.useUnifiedTopology &&
-          get(db, 's.topology.s.description.type') === 'Single') {
-        const server = Array.from(db.s.topology.s.servers.values())[0];
-        server.s.pool.on('reconnect', () => {
-          _handleReconnect();
-        });
-        server.s.pool.on('reconnectFailed', () => {
-          _this.emit('reconnectFailed');
-        });
-        server.s.pool.on('timeout', () => {
-          _this.emit('timeout');
-        });
+      const type = get(db, 's.topology.s.description.type', '');
+      if (options.useUnifiedTopology) {
+        if (type === 'Single') {
+          const server = Array.from(db.s.topology.s.servers.values())[0];
+          server.s.pool.on('reconnect', () => {
+            _handleReconnect();
+          });
+          server.s.pool.on('reconnectFailed', () => {
+            _this.emit('reconnectFailed');
+          });
+          server.s.pool.on('timeout', () => {
+            _this.emit('timeout');
+          });
+        } else if (type.startsWith('ReplicaSet')) {
+          db.on('close', function() {
+            const type = get(db, 's.topology.s.description.type', '');
+            if (type !== 'ReplicaSetWithPrimary') {
+              // Implicitly emits 'disconnected'
+              _this.readyState = STATES.disconnected;
+            }
+          });
+        }
       }
 
       // Backwards compat for mongoose 4.x
@@ -674,10 +684,12 @@ Connection.prototype.openUri = function(uri, options, callback) {
           _this.emit('attemptReconnect');
         });
       }
-      db.on('close', function() {
-        // Implicitly emits 'disconnected'
-        _this.readyState = STATES.disconnected;
-      });
+      if (!options.useUnifiedTopology || !type.startsWith('ReplicaSet')) {
+        db.on('close', function() {
+          // Implicitly emits 'disconnected'
+          _this.readyState = STATES.disconnected;
+        });
+      }
       client.on('left', function() {
         if (_this.readyState === STATES.connected &&
             get(db, 's.topology.s.coreTopology.s.replicaSetState.topologyType') === 'ReplicaSetNoPrimary') {

From 6602b7d26d011fa91ecde7202c1459ef16a08b72 Mon Sep 17 00:00:00 2001
From: Katherine <krosenk729@gmail.com>
Date: Wed, 16 Oct 2019 15:07:41 -0400
Subject: [PATCH 0088/2348] Updating link to broken image on home page

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 4ad2c1a87d5..996a9bf3ac1 100644
--- a/index.pug
+++ b/index.pug
@@ -221,7 +221,7 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/lemon-law/logo.png" style="height: 100px">
               </a>
               <a href="https://uxplanet.org/top-ui-ux-design-agencies-user-experience-firms-8c54697e290">
-                <img class="sponsor" src="https://images.opencollective.com/ux-top-5/cae5dfe/logo.png" style="height: 100px">
+                <img class="sponsor" src="https://miro.medium.com/fit/c/160/160/1*A0FnBy5FBoVQC02SZXLXPg.png" style="height: 100px">
               </a>
               <a href="https://proxybaylist.org/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy-bay/e176fe4/avatar.png" style="height: 100px">

From 9a6758c04ec8bcbfc00e2575f6b1d7a1c1240844 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Oct 2019 10:55:54 -0400
Subject: [PATCH 0089/2348] chore: now working on 5.7.6

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 66547f6eb5d..c7abe077205 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.5",
+  "version": "5.7.6-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 0291ffa6c1fe9907a0154d71bf24158da4d4b607 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Oct 2019 10:56:00 -0400
Subject: [PATCH 0090/2348] docs(schematypes): add a section about the `type`
 property

Fix #8227
---
 docs/schematypes.pug | 61 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 60 insertions(+), 1 deletion(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index ade9a47a067..7f2daac0bc4 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -34,6 +34,14 @@ block content
       <li><a href="#path">The `schema.path()` Function</a></li>
     </ul>
 
+    * [What is a SchemaType?](#what-is-a-schematype)
+    * [The `type` Key](#type-key)
+    * [SchemaType Options](#schematype-options)
+    * [Usage Notes](#usage-notes)
+    * [Getters](#getters)
+    * [Custom Types](#customtypes)
+    * [The `schema.path()` Function](#path)
+
     <h3 id="what-is-a-schematype"><a href="#what-is-a-schematype">What is a SchemaType?</a></h3>
 
     You can think of a Mongoose schema as the configuration object for a
@@ -125,6 +133,57 @@ block content
     m.save(callback);
     ```
 
+    <h3 id="type-key"><a href="#type-key">The `type` Key</a></h3>
+
+    `type` is a special property in Mongoose schemas. When Mongoose finds
+    a nested property named `type` in your schema, Mongoose assumes that
+    it needs to define a SchemaType with the given type.
+
+    ```javascript
+    // 3 string SchemaTypes: 'name', 'nested.firstName', 'nested.lastName'
+    const schema = new Schema({
+      name: { type: String },
+      nested: {
+        firstName: { type: String },
+        lastName: { type: String }
+      }
+    });
+    ```
+
+    As a consequence, [you need a little extra work to define a property named `type` in your schema](/docs/faq.html#type-key).
+    For example, suppose you're building a stock portfolio app, and you
+    want to store the asset's `type` (stock, bond, ETF, etc.). Naively,
+    you might define your schema as shown below:
+
+    ```javascript
+    const holdingSchema = new Schema({
+      // You might expect `asset` to be an object that has 2 properties,
+      // but unfortunately `type` is special in Mongoose so mongoose
+      // interprets this schema to mean that `asset` is a string
+      asset: {
+        type: String,
+        ticker: String
+      }
+    });
+    ```
+
+    However, when Mongoose sees `type: String`, it assumes that you mean
+    `asset` should be a string, not an object with a property `type`.
+    The correct way to define an object with a property `type` is shown
+    below.
+
+    ```javascript
+    const holdingSchema = new Schema({
+      asset: {
+        // Workaround to make sure Mongoose knows `asset` is an object
+        // and `asset.type` is a string, rather than thinking `asset`
+        // is a string.
+        type: { type: String },
+        ticker: String
+      }
+    });
+    ```
+
     <h3 id="schematype-options"><a href="#schematype-options">SchemaType Options</a></h3>
 
     You can declare a schema type using the type directly, or an object with
@@ -234,7 +293,7 @@ block content
     * `min`: Date
     * `max`: Date
 
-    <h3 id="usage-notes"><a href="#usage-notes">Usage notes</a></h3>
+    <h3 id="usage-notes"><a href="#usage-notes">Usage Notes</a></h3>
 
     <h4 id="strings">String</h4>
 

From 64ee884839a506d61d97c5c36f4121653cd4719d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Oct 2019 11:51:23 -0400
Subject: [PATCH 0091/2348] docs: add documentarraypath to API docs, including
 DocumentArrayPath#discriminator()

Fix #8164
---
 docs/source/api.js             |  4 +++
 lib/model.js                   |  2 +-
 lib/schema/SingleNestedPath.js |  7 +++---
 lib/schema/documentarray.js    | 46 +++++++++++++++++++++-------------
 4 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/docs/source/api.js b/docs/source/api.js
index 011ab45fe45..2fdf9c4e352 100644
--- a/docs/source/api.js
+++ b/docs/source/api.js
@@ -24,6 +24,7 @@ const files = [
   'lib/virtualtype.js',
   'lib/error/index.js',
   'lib/types/core_array.js',
+  'lib/schema/documentarray.js',
   'lib/schema/SingleNestedPath.js',
   'lib/options/SchemaTypeOptions.js',
   'lib/options/SchemaArrayOptions.js',
@@ -63,6 +64,9 @@ function parse() {
     if (name === 'core_array') {
       name = 'array';
     }
+    if (name === 'documentarray') {
+      name = 'DocumentArrayPath';
+    }
     const data = {
       name: name.charAt(0).toUpperCase() === name.charAt(0) ? name : name.charAt(0).toUpperCase() + name.substr(1),
       props: []
diff --git a/lib/model.js b/lib/model.js
index eca0693a4b9..0982d97788c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1066,7 +1066,7 @@ Model.exists = function exists(filter, options, callback) {
  *
  * @param {String} name discriminator model name
  * @param {Schema} schema discriminator model schema
- * @param {String} value the string stored in the `discriminatorKey` property
+ * @param {String} [value] the string stored in the `discriminatorKey` property. If not specified, Mongoose uses the `name` parameter.
  * @api public
  */
 
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 3862529619c..00032ad793e 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -274,17 +274,18 @@ SingleNestedPath.prototype.doValidateSync = function(value, scope, options) {
  *     const shapeSchema = Schema({ name: String }, { discriminatorKey: 'kind' });
  *     const schema = Schema({ shape: shapeSchema });
  *
- *     const singleNestedPath = parentSchema.path('child');
+ *     const singleNestedPath = parentSchema.path('shape');
  *     singleNestedPath.discriminator('Circle', Schema({ radius: Number }));
  *
  * @param {String} name
  * @param {Schema} schema fields to add to the schema for instances of this sub-class
+ * @param {String} [value] the string stored in the `discriminatorKey` property. If not specified, Mongoose uses the `name` parameter.
  * @see discriminators /docs/discriminators.html
  * @api public
  */
 
-SingleNestedPath.prototype.discriminator = function(name, schema, tiedValue) {
-  discriminator(this.caster, name, schema, tiedValue);
+SingleNestedPath.prototype.discriminator = function(name, schema, value) {
+  discriminator(this.caster, name, schema, value);
 
   this.caster.discriminators[name] = _createConstructor(schema, this.caster);
 
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 9229676f77d..4bacffd3630 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -29,7 +29,7 @@ let Subdocument;
  * @api public
  */
 
-function DocumentArray(key, schema, options, schemaOptions) {
+function DocumentArrayPath(key, schema, options, schemaOptions) {
   const EmbeddedDocument = _createConstructor(schema, options);
   EmbeddedDocument.prototype.$basePath = key;
 
@@ -62,24 +62,23 @@ function DocumentArray(key, schema, options, schemaOptions) {
  *
  * @api public
  */
-DocumentArray.schemaName = 'DocumentArray';
+DocumentArrayPath.schemaName = 'DocumentArray';
 
 /**
  * Options for all document arrays.
  *
  * - `castNonArrays`: `true` by default. If `false`, Mongoose will throw a CastError when a value isn't an array. If `true`, Mongoose will wrap the provided value in an array before casting.
  *
- * @static options
  * @api public
  */
 
-DocumentArray.options = { castNonArrays: true };
+DocumentArrayPath.options = { castNonArrays: true };
 
 /*!
  * Inherits from ArrayType.
  */
-DocumentArray.prototype = Object.create(ArrayType.prototype);
-DocumentArray.prototype.constructor = DocumentArray;
+DocumentArrayPath.prototype = Object.create(ArrayType.prototype);
+DocumentArrayPath.prototype.constructor = DocumentArrayPath;
 
 /*!
  * Ignore
@@ -122,11 +121,24 @@ function _createConstructor(schema, options, baseClass) {
   return EmbeddedDocument;
 }
 
-/*!
- * Ignore
+/**
+ * Adds a discriminator to this document array.
+ *
+ * ####Example:
+ *     const shapeSchema = Schema({ name: String }, { discriminatorKey: 'kind' });
+ *     const schema = Schema({ shapes: [shapeSchema] });
+ *
+ *     const docArrayPath = parentSchema.path('shapes');
+ *     docArrayPath.discriminator('Circle', Schema({ radius: Number }));
+ *
+ * @param {String} name
+ * @param {Schema} schema fields to add to the schema for instances of this sub-class
+ * @param {String} [value] the string stored in the `discriminatorKey` property. If not specified, Mongoose uses the `name` parameter.
+ * @see discriminators /docs/discriminators.html
+ * @api public
  */
 
-DocumentArray.prototype.discriminator = function(name, schema, tiedValue) {
+DocumentArrayPath.prototype.discriminator = function(name, schema, tiedValue) {
   if (typeof name === 'function') {
     name = utils.getFunctionName(name);
   }
@@ -155,7 +167,7 @@ DocumentArray.prototype.discriminator = function(name, schema, tiedValue) {
  * @api private
  */
 
-DocumentArray.prototype.doValidate = function(array, fn, scope, options) {
+DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
   // lazy load
   MongooseDocumentArray || (MongooseDocumentArray = require('../types/documentarray'));
 
@@ -231,7 +243,7 @@ DocumentArray.prototype.doValidate = function(array, fn, scope, options) {
  * @api private
  */
 
-DocumentArray.prototype.doValidateSync = function(array, scope) {
+DocumentArrayPath.prototype.doValidateSync = function(array, scope) {
   const schemaTypeError = SchemaType.prototype.doValidateSync.call(this, array, scope);
   if (schemaTypeError != null) {
     schemaTypeError.$isArrayValidatorError = true;
@@ -277,7 +289,7 @@ DocumentArray.prototype.doValidateSync = function(array, scope) {
  * ignore
  */
 
-DocumentArray.prototype.getDefault = function(scope) {
+DocumentArrayPath.prototype.getDefault = function(scope) {
   let ret = typeof this.defaultValue === 'function'
     ? this.defaultValue.call(scope)
     : this.defaultValue;
@@ -316,7 +328,7 @@ DocumentArray.prototype.getDefault = function(scope) {
  * @api private
  */
 
-DocumentArray.prototype.cast = function(value, doc, init, prev, options) {
+DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
   // lazy load
   MongooseDocumentArray || (MongooseDocumentArray = require('../types/documentarray'));
 
@@ -326,7 +338,7 @@ DocumentArray.prototype.cast = function(value, doc, init, prev, options) {
   const _opts = { transform: false, virtuals: false };
 
   if (!Array.isArray(value)) {
-    if (!init && !DocumentArray.options.castNonArrays) {
+    if (!init && !DocumentArrayPath.options.castNonArrays) {
       throw new CastError('DocumentArray', util.inspect(value), this.path);
     }
     // gh-2442 mark whole array as modified if we're initializing a doc from
@@ -416,7 +428,7 @@ DocumentArray.prototype.cast = function(value, doc, init, prev, options) {
  * ignore
  */
 
-DocumentArray.prototype.clone = function() {
+DocumentArrayPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
   const schematype = new this.constructor(this.path, this.schema, options, this.schemaOptions);
   schematype.validators = this.validators.slice();
@@ -429,7 +441,7 @@ DocumentArray.prototype.clone = function() {
  * Scopes paths selected in a query to this array.
  * Necessary for proper default application of subdocument values.
  *
- * @param {DocumentArray} array - the array to scope `fields` paths
+ * @param {DocumentArrayPath} array - the array to scope `fields` paths
  * @param {Object|undefined} fields - the root fields selected in the query
  * @param {Boolean|undefined} init - if we are being created part of a query result
  */
@@ -469,4 +481,4 @@ function scopePaths(array, fields, init) {
  * Module exports.
  */
 
-module.exports = DocumentArray;
+module.exports = DocumentArrayPath;

From 2e9edc31d1a5fe4fa24734523dfc4998f05f547b Mon Sep 17 00:00:00 2001
From: Wojtek <gosuhiman@gmail.com>
Date: Fri, 18 Oct 2019 14:03:10 +0200
Subject: [PATCH 0092/2348] Update Connection.close docs

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index d3fde9d4c15..785796c1f50 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -757,7 +757,7 @@ const handleUseMongoClient = function handleUseMongoClient(options) {
  *
  * @param {Boolean} [force] optional
  * @param {Function} [callback] optional
- * @return {Connection} self
+ * @return {Promise}
  * @api public
  */
 

From efd08ef8290d942eca8668dedbae135711f6324f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 18 Oct 2019 13:57:10 -0400
Subject: [PATCH 0093/2348] test(document): repro #8251

---
 test/document.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 1e32f7fe291..ab1bbe9f514 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8113,4 +8113,21 @@ describe('document', function() {
       yield person.save();
     });
   });
+
+  it('setting single nested subdoc with timestamps (gh-8251)', function() {
+    const ActivitySchema = Schema({ description: String }, { timestamps: true });
+    const RequestSchema = Schema({ activity: ActivitySchema });
+    const Request = db.model('gh8251', RequestSchema);
+
+    return co(function*() {
+      const doc = yield Request.create({
+        activity: { description: 'before' }
+      });
+      doc.activity.set({ description: 'after' });
+      yield doc.save();
+
+      const fromDb = yield Request.findOne().lean();
+      assert.equal(fromDb.activity.description, 'after');
+    });
+  });
 });

From 875d681b06549a78215ef1543274517e52895dbd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 18 Oct 2019 13:59:04 -0400
Subject: [PATCH 0094/2348] fix(document): fix TypeError when setting a single
 nested subdoc with timestamps

Fix #8251
---
 lib/types/subdocument.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index cb4db5c1651..ce23a5afb79 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -117,8 +117,11 @@ Subdocument.prototype.markModified = function(path) {
 
 Subdocument.prototype.isModified = function(paths, modifiedPaths) {
   if (this.$parent && this.$basePath) {
-    paths = (Array.isArray(paths) ? paths : paths.split(' ')).
-      map(p => [this.$basePath, p].join('.'));
+    if (Array.isArray(paths) || typeof paths === 'string') {
+      paths = (Array.isArray(paths) ? paths : paths.split(' '));
+      paths = paths.map(p => [this.$basePath, p].join('.'));
+    }
+
     return this.$parent.isModified(paths, modifiedPaths);
   }
 

From ba18b9de2e68ad7bc0982a72f8d648a15dd1497c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 19 Oct 2019 10:14:36 -0400
Subject: [PATCH 0095/2348] test(cursor): repro #8235

---
 test/helpers/cursor.eachAsync.test.js | 30 +++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 test/helpers/cursor.eachAsync.test.js

diff --git a/test/helpers/cursor.eachAsync.test.js b/test/helpers/cursor.eachAsync.test.js
new file mode 100644
index 00000000000..f64ea2ffe27
--- /dev/null
+++ b/test/helpers/cursor.eachAsync.test.js
@@ -0,0 +1,30 @@
+'use strict';
+
+const assert = require('assert');
+const eachAsync = require('../../lib/helpers/cursor/eachAsync');
+
+describe('eachAsync()', function() {
+  it('exhausts large cursor without parallel calls (gh-8235)', function() {
+    this.timeout(10000);
+    
+    let numInProgress = 0;
+    let num = 0;
+    const max = 1000;
+    let processed = 0;
+
+    function next(cb) {
+      assert.equal(numInProgress, 0);
+      ++numInProgress;
+      setTimeout(function() {
+        --numInProgress;
+        if (num++ >= max) {
+          return cb(null, null);
+        }
+        cb(null, { name: `doc${num}` });
+      }, 0);
+    }
+
+    return eachAsync(next, () => Promise.resolve(++processed), { parallel: 8 }).
+      then(() => assert.equal(processed, max));
+  });
+});
\ No newline at end of file

From a47ac98c6ece198a2f508a6e19813770d9eda5c3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 19 Oct 2019 10:15:35 -0400
Subject: [PATCH 0096/2348] fix(cursor): fix issue with long-running
 `eachAsync()` cursor

Fix #8235
---
 lib/helpers/cursor/eachAsync.js       | 104 +++++++++++++-------------
 test/helpers/cursor.eachAsync.test.js |   2 +-
 2 files changed, 55 insertions(+), 51 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index a343c01b0aa..472dbeee187 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -22,6 +22,7 @@ const utils = require('../../utils');
 
 module.exports = function eachAsync(next, fn, options, callback) {
   const parallel = options.parallel || 1;
+  const enqueue = asyncQueue();
 
   const handleNextResult = function(doc, callback) {
     const promise = fn(doc);
@@ -37,71 +38,74 @@ module.exports = function eachAsync(next, fn, options, callback) {
   const iterate = function(callback) {
     let drained = false;
 
-    const getAndRun = function(cb) {
-      _next(function(err, doc) {
-        if (err) return cb(err);
-        if (drained) {
-          return;
-        }
-        if (doc == null) {
-          drained = true;
-          return callback(null);
-        }
-        handleNextResult(doc, function(err) {
-          if (err) return cb(err);
-          // Make sure to clear the stack re: gh-4697
-          setTimeout(function() {
-            getAndRun(cb);
-          }, 0);
-        });
-      });
-    };
-
     let error = null;
     for (let i = 0; i < parallel; ++i) {
-      getAndRun(err => {
-        if (error != null) {
-          return;
+      enqueue(fetch);
+    }
+
+    function fetch(done) {
+      if (drained || error) {
+        return done();
+      }
+
+      next(function(err, doc) {
+        if (drained || error) {
+          return done();
         }
         if (err != null) {
           error = err;
-          return callback(err);
+          callback(err);
+          return done();
+        }
+        if (doc == null) {
+          drained = true;
+          callback(null);
+          return done();
         }
+
+        done();
+
+        handleNextResult(doc, function(err) {
+          if (err != null) {
+            error = err;
+            return callback(err);
+          }
+
+          setTimeout(() => enqueue(fetch), 0);
+        });
       });
     }
   };
 
-  const _nextQueue = [];
   return utils.promiseOrCallback(callback, cb => {
     iterate(cb);
   });
+};
 
-  // `next()` can only execute one at a time, so make sure we always execute
-  // `next()` in series, while still allowing multiple `fn()` instances to run
-  // in parallel.
-  function _next(cb) {
-    if (_nextQueue.length === 0) {
-      return next(_step(cb));
-    }
-    _nextQueue.push(cb);
-  }
+// `next()` can only execute one at a time, so make sure we always execute
+// `next()` in series, while still allowing multiple `fn()` instances to run
+// in parallel.
+function asyncQueue() {
+  const _queue = [];
+  let inProgress = null;
+  let id = 0;
 
-  function _step(cb) {
-    return function(err, doc) {
-      if (err != null) {
-        return cb(err);
-      }
-      cb(null, doc);
+  return function enqueue(fn) {
+    if (_queue.length === 0 && inProgress == null) {
+      inProgress = id++;
+      return fn(_step);
+    }
+    _queue.push(fn);
+  };
 
-      if (doc == null) {
-        return;
+  function _step() {
+    setTimeout(() => {
+      inProgress = null;
+      if (_queue.length > 0) {
+        inProgress = id++;
+        const fn = _queue.shift();
+        fn(_step);
       }
-
-      setTimeout(() => {
-        if (_nextQueue.length > 0) {
-          next(_step(_nextQueue.unshift()));
-        }
-      }, 0);
-    };
+    }, 0);
   }
-};
+}
\ No newline at end of file
diff --git a/test/helpers/cursor.eachAsync.test.js b/test/helpers/cursor.eachAsync.test.js
index f64ea2ffe27..14c4e1f5847 100644
--- a/test/helpers/cursor.eachAsync.test.js
+++ b/test/helpers/cursor.eachAsync.test.js
@@ -6,7 +6,7 @@ const eachAsync = require('../../lib/helpers/cursor/eachAsync');
 describe('eachAsync()', function() {
   it('exhausts large cursor without parallel calls (gh-8235)', function() {
     this.timeout(10000);
-    
+
     let numInProgress = 0;
     let num = 0;
     const max = 1000;

From df31656f2a7d3189a42c56d2fcbbc92fc1d03540 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 19 Oct 2019 14:35:45 -0400
Subject: [PATCH 0097/2348] docs(middleware): update document middleware list

---
 docs/middleware.pug | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index 6b326fd4b14..c232023c875 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -44,10 +44,12 @@ block content
     Document middleware is supported for the following document functions.
     In document middleware functions, `this` refers to the document.
 
-    * [validate](./api.html#document_Document-validate)
-    * [save](./api.html#model_Model-save)
-    * [remove](./api.html#model_Model-remove)
-    * [init](./api.html#document_Document-init) (note: init hooks are [synchronous](#synchronous))
+    * [validate](/docs/api/document.html#document_Document-validate)
+    * [save](/docs/api/model.html#model_Model-save)
+    * [remove](/docs/api/model.html#model_Model-remove)
+    * [updateOne](/docs/api/document.html#document_Document-updateOne)
+    * [deleteOne](/docs/api/model.html#model_Model-deleteOne)
+    * [init](/docs/api/document.html#document_Document-init) (note: init hooks are [synchronous](#synchronous))
 
     Query middleware is supported for the following Model and Query functions.
     In query middleware functions, `this` refers to the query.

From 8ddfc0a563049370ee8e3adb5a8ea3841037da28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 20 Oct 2019 10:54:06 -0400
Subject: [PATCH 0098/2348] test(populate): repro #8247

---
 test/model.populate.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 699973d53ff..57c7821de2a 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8667,4 +8667,27 @@ describe('model: populate:', function() {
       assert.equal(foo2.children[0].bar.name, 'bar');
     });
   });
+
+  it('checking `populated()` on a document array element (gh-8247)', function() {
+    const authorSchema = Schema({ name: String });
+    const subSchema = Schema({
+      author: { type: Schema.Types.ObjectId, ref: 'gh8247_Author' },
+      comment: String
+    });
+    const pageSchema = Schema({ title: String, comments: [subSchema] });
+    const Author = db.model('gh8247_Author', authorSchema);
+    const Page = db.model('gh8247_Page', pageSchema);
+
+    return co(function*() {
+      const doc = yield Author.create({ name: 'test author' });
+      yield Page.create({ comments: [{ author: doc._id }] });
+
+      const fromDb = yield Page.findOne().populate('comments.author');
+      assert.ok(Array.isArray(fromDb.populated('comments.author')));
+      assert.equal(fromDb.populated('comments.author').length, 1);
+      assert.equal(fromDb.comments[0].author.name, 'test author');
+
+      assert.ok(fromDb.comments[0].populated('author'));
+    });
+  });
 });

From 25b679851663af7bd70a5a3b4cd4f08f7085380f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 20 Oct 2019 10:55:35 -0400
Subject: [PATCH 0099/2348] fix(populate): make `ArraySubdocument#populated()`
 return a value when the path is populated

Re: #8247
---
 lib/document.js | 43 +++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 41 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index b816b8bde97..c725b2083ab 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -486,8 +486,7 @@ Document.prototype.$__init = function(doc, opts) {
 
   // handle docs with populated paths
   // If doc._id is not null or undefined
-  if (doc._id !== null && doc._id !== undefined &&
-    opts.populated && opts.populated.length) {
+  if (doc._id != null && opts.populated && opts.populated.length) {
     const id = String(doc._id);
     for (let i = 0; i < opts.populated.length; ++i) {
       const item = opts.populated[i];
@@ -501,6 +500,8 @@ Document.prototype.$__init = function(doc, opts) {
 
   init(this, doc, this._doc, opts);
 
+  markArraySubdocsPopulated(this, opts.populated);
+
   this.emit('init', this);
   this.constructor.emit('init', this);
 
@@ -509,6 +510,44 @@ Document.prototype.$__init = function(doc, opts) {
   return this;
 };
 
+/*!
+ * If populating a path within a document array, make sure each
+ * subdoc within the array knows its subpaths are populated.
+ *
+ * ####Example:
+ *     const doc = await Article.findOne().populate('comments.author');
+ *     doc.comments[0].populated('author'); // Should be set
+ */
+
+function markArraySubdocsPopulated(doc, populated) {
+  if (doc._id == null || populated == null || populated.length === 0) {
+    return;
+  }
+
+  const id = String(doc._id);
+  for (const item of populated) {
+    if (item.isVirtual) {
+      continue;
+    }
+    const path = item.path;
+    const pieces = path.split('.');
+    for (let i = 0; i < pieces.length - 1; ++i) {
+      const subpath = pieces.slice(0, i + 1).join('.');
+      const rest = pieces.slice(i + 1).join('.');
+      const val = doc.get(subpath);
+      if (val == null) {
+        continue;
+      }
+      if (val.isMongooseDocumentArray) {
+        for (let j = 0; j < val.length; ++j) {
+          val[j].populated(rest, item._docs[id][j], item);
+        }
+        break;
+      }
+    }
+  }
+}
+
 /*!
  * Init helper.
  *

From e5f88752b7609a494d2c9b7f3e620317634c20d2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 20 Oct 2019 11:07:38 -0400
Subject: [PATCH 0100/2348] chore: add bonus.ca to opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 996a9bf3ac1..441589a5b25 100644
--- a/index.pug
+++ b/index.pug
@@ -256,6 +256,9 @@ html(lang='en')
               <a href="https://loanscouter.com/">
                 <img class="sponsor" src="https://images.opencollective.com/lead-supply/7400b71/logo.png" style="height: 100px">
               </a>
+              <a href="https://www.bonus.ca">
+                <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 9b986f5cf1aeac6b371200e23bc2172cefcd9e65 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 20 Oct 2019 12:01:36 -0400
Subject: [PATCH 0101/2348] test(document): repro #8237

---
 test/document.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index ab1bbe9f514..c1e3e796f07 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -130,6 +130,15 @@ describe('document', function() {
     db.close(done);
   });
 
+  describe('constructor', function() {
+    it('supports passing in schema directly (gh-8237)', function() {
+      const myUserDoc = new Document({}, { name: String });
+      assert.ok(!myUserDoc.name);
+      myUserDoc.name = 123;
+      assert.strictEqual(myUserDoc.name, '123');
+    });
+  });
+
   describe('delete', function() {
     it('deletes the document', function() {
       const schema = new Schema({ x: String });

From d69ab22c140e0e32efceee5b4a8d6efbe12c9d77 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 20 Oct 2019 12:01:44 -0400
Subject: [PATCH 0102/2348] fix(document): support calling `Document`
 constructor directly in Node.js

Fix #8237
---
 lib/document.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index c725b2083ab..e108d55679c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -10,6 +10,7 @@ const MongooseError = require('./error/index');
 const MixedSchema = require('./schema/mixed');
 const ObjectExpectedError = require('./error/objectExpected');
 const ObjectParameterError = require('./error/objectParameter');
+const Schema = require('./schema');
 const StrictModeError = require('./error/strict');
 const ValidatorError = require('./schematype').ValidatorError;
 const VirtualType = require('./virtualtype');
@@ -64,6 +65,17 @@ function Document(obj, fields, skipId, options) {
   }
   options = options || {};
 
+  // Support `browserDocument.js` syntax
+  if (this.schema == null) {
+    const _schema = utils.isObject(fields) && !fields.instanceOfSchema ?
+      new Schema(fields) :
+      fields;
+    this.$__setSchema(_schema);
+    fields = skipId;
+    skipId = options;
+    options = arguments[4] || {};
+  }
+
   this.$__ = new InternalCache;
   this.$__.emitter = new EventEmitter();
   this.isNew = 'isNew' in options ? options.isNew : true;

From 4e900eb32ec43a333e1e819dd70c8bc4647603fd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Oct 2019 12:20:26 -0400
Subject: [PATCH 0103/2348] test(populate): repro #8247

---
 test/model.populate.test.js | 76 +++++++++++++++++++++++++++++--------
 1 file changed, 60 insertions(+), 16 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 57c7821de2a..0ab15770983 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8668,26 +8668,70 @@ describe('model: populate:', function() {
     });
   });
 
-  it('checking `populated()` on a document array element (gh-8247)', function() {
-    const authorSchema = Schema({ name: String });
-    const subSchema = Schema({
-      author: { type: Schema.Types.ObjectId, ref: 'gh8247_Author' },
-      comment: String
+  describe('gh-8247', function() {
+    let Author;
+    let Page;
+
+    before(function() {
+      const authorSchema = Schema({ name: String });
+      const subSchema = Schema({
+        author: { type: Schema.Types.ObjectId, ref: 'gh8247_Author' },
+        comment: String
+      });
+      const pageSchema = Schema({ title: String, comments: [subSchema] });
+      Author = db.model('gh8247_Author', authorSchema);
+      Page = db.model('gh8247_Page', pageSchema);
     });
-    const pageSchema = Schema({ title: String, comments: [subSchema] });
-    const Author = db.model('gh8247_Author', authorSchema);
-    const Page = db.model('gh8247_Page', pageSchema);
 
-    return co(function*() {
-      const doc = yield Author.create({ name: 'test author' });
-      yield Page.create({ comments: [{ author: doc._id }] });
+    this.beforeEach(() => co(function*() {
+      yield Author.deleteMany({});
+      yield Page.deleteMany({});
+    }));
+
+    it('checking `populated()` on a document array element (gh-8247)', function() {
+      return co(function*() {
+        const doc = yield Author.create({ name: 'test author' });
+        yield Page.create({ comments: [{ author: doc._id }] });
+
+        const fromDb = yield Page.findOne().populate('comments.author');
+        assert.ok(Array.isArray(fromDb.populated('comments.author')));
+        assert.equal(fromDb.populated('comments.author').length, 1);
+        assert.equal(fromDb.comments[0].author.name, 'test author');
 
-      const fromDb = yield Page.findOne().populate('comments.author');
-      assert.ok(Array.isArray(fromDb.populated('comments.author')));
-      assert.equal(fromDb.populated('comments.author').length, 1);
-      assert.equal(fromDb.comments[0].author.name, 'test author');
+        assert.ok(fromDb.comments[0].populated('author'));
+      });
+    });
 
-      assert.ok(fromDb.comments[0].populated('author'));
+    it('updates top-level populated() when pushing elements onto a document array with single populated path (gh-8247)', function() {
+      return co(function*() {
+        const docs = yield Author.create([
+          { name: 'test1' },
+          { name: 'test2' }
+        ]);
+        yield Page.create({ comments: [{ author: docs[0]._id }] });
+
+        // Try setting to non-manually populated path...
+        let fromDb = yield Page.findOne().populate('comments.author');
+        assert.ok(Array.isArray(fromDb.populated('comments.author')));
+        assert.equal(fromDb.populated('comments.author').length, 1);
+        assert.equal(fromDb.comments[0].author.name, 'test1');
+
+        fromDb.comments.push({ author: docs[1]._id });
+        let pop = fromDb.populated('comments.author');
+        assert.equal(pop.length, 2);
+        assert.equal(pop[0].toHexString(), docs[0]._id.toHexString());
+        assert.equal(pop[1], null);
+
+        // And try setting to populated path
+        fromDb = yield Page.findOne().populate('comments.author');
+        assert.ok(Array.isArray(fromDb.populated('comments.author')));
+        assert.equal(fromDb.populated('comments.author').length, 1);
+        assert.equal(fromDb.comments[0].author.name, 'test1');
+
+        fromDb.comments.push({ author: docs[1] });
+        pop = fromDb.populated('comments.author');
+        assert.equal(pop.length, 2);
+      });
     });
   });
 });

From a81211de24c045a29b1df9ffba288608ee57f32b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Oct 2019 12:20:43 -0400
Subject: [PATCH 0104/2348] fix(populate): add document array subpaths to
 parent doc `populated()` when calling `DocumentArray#push()`

Fix #8247
---
 lib/document.js         |  7 +------
 lib/types/core_array.js | 21 ++++++++++++++++++++-
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index e108d55679c..23c30db1ce0 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1130,12 +1130,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
     let didPopulate = false;
     if (refMatches && val instanceof Document) {
-      if (this.ownerDocument) {
-        this.ownerDocument().populated(this.$__fullPath(path),
-          val._id, { [populateModelSymbol]: val.constructor });
-      } else {
-        this.populated(path, val._id, { [populateModelSymbol]: val.constructor });
-      }
+      this.populated(path, val._id, { [populateModelSymbol]: val.constructor });
       didPopulate = true;
     }
 
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 9f0aa9f5f25..92121d9a523 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -628,11 +628,30 @@ class CoreMongooseArray extends Array {
 
     _checkManualPopulation(this, arguments);
 
+    const parent = this[arrayParentSymbol];
     let values = [].map.call(arguments, this._mapCast, this);
-    values = this[arraySchemaSymbol].applySetters(values, this[arrayParentSymbol], undefined,
+    values = this[arraySchemaSymbol].applySetters(values, parent, undefined,
       undefined, { skipDocumentArrayCast: true });
     const ret = [].push.apply(this, values);
 
+    // If this is a document array, each element may contain single
+    // populated paths, so we need to modify the top-level document's
+    // populated cache. See gh-8247.
+    if (this.isMongooseDocumentArray && parent.$__.populated != null) {
+      const populatedPaths = Object.keys(parent.$__.populated).
+        filter(p => p.startsWith(this[arrayPathSymbol] + '.'));
+
+      for (const path of populatedPaths) {
+        const remnant = path.slice((this[arrayPathSymbol] + '.').length);
+        if (!Array.isArray(parent.$__.populated[path].value)) {
+          continue;
+        }
+        for (const val of values) {
+          parent.$__.populated[path].value.push(val.populated(remnant));
+        }
+      }
+    }
+
     this._registerAtomic('$push', values);
     this._markModified();
     return ret;

From 29c5f1a5be732dacee506c85d2e0cb3804eb432b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Oct 2019 16:11:40 -0400
Subject: [PATCH 0105/2348] fix(options): add missing minlength and maxlength
 to SchemaStringOptions

Fix #8256
---
 lib/options/SchemaStringOptions.js | 26 ++++++++++++++++++++++
 lib/schema/string.js               | 35 ++++++++++++++++++++----------
 test/schema.test.js                |  9 ++++++++
 3 files changed, 58 insertions(+), 12 deletions(-)

diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index 11e8848a787..8c6bb0ac067 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -88,6 +88,32 @@ Object.defineProperty(SchemaStringOptions.prototype, 'trim', opts);
 
 Object.defineProperty(SchemaStringOptions.prototype, 'uppercase', opts);
 
+/**
+ * If set, Mongoose will add a custom validator that ensures the given
+ * string's `length` is at least the given number.
+ *
+ * @api public
+ * @property minlength
+ * @memberOf SchemaStringOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'minlength', opts);
+
+/**
+ * If set, Mongoose will add a custom validator that ensures the given
+ * string's `length` is at most the given number.
+ *
+ * @api public
+ * @property maxlength
+ * @memberOf SchemaStringOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'maxlength', opts);
+
 /*!
  * ignore
  */
diff --git a/lib/schema/string.js b/lib/schema/string.js
index fe3e9568a07..645c4c3571e 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -43,7 +43,12 @@ SchemaString.schemaName = 'String';
  */
 SchemaString.prototype = Object.create(SchemaType.prototype);
 SchemaString.prototype.constructor = SchemaString;
-SchemaString.prototype.OptionsConstructor = SchemaStringOptions;
+Object.defineProperty(SchemaString.prototype, 'OptionsConstructor', {
+  configurable: false,
+  enumerable: false,
+  writable: false,
+  value: SchemaStringOptions
+});
 
 /*!
  * ignore
@@ -574,17 +579,23 @@ function handleArray(val) {
   });
 }
 
-SchemaString.prototype.$conditionalHandlers =
-    utils.options(SchemaType.prototype.$conditionalHandlers, {
-      $all: handleArray,
-      $gt: handleSingle,
-      $gte: handleSingle,
-      $lt: handleSingle,
-      $lte: handleSingle,
-      $options: String,
-      $regex: handleSingle,
-      $not: handleSingle
-    });
+const $conditionalHandlers = utils.options(SchemaType.prototype.$conditionalHandlers, {
+  $all: handleArray,
+  $gt: handleSingle,
+  $gte: handleSingle,
+  $lt: handleSingle,
+  $lte: handleSingle,
+  $options: String,
+  $regex: handleSingle,
+  $not: handleSingle
+});
+
+Object.defineProperty(SchemaString.prototype, '$conditionalHandlers', {
+  configurable: false,
+  enumerable: false,
+  writable: false,
+  value: Object.freeze($conditionalHandlers)
+});
 
 /**
  * Casts contents for queries.
diff --git a/test/schema.test.js b/test/schema.test.js
index 02c6c22baa9..7b4d6435c87 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2135,4 +2135,13 @@ describe('schema', function() {
     assert.strictEqual(schema.path('name').isRequired, false);
     assert.strictEqual(schema.path('age').isRequired, false);
   });
+
+  it('SchemaStringOptions line up with schema/string (gh-8256)', function() {
+    const SchemaStringOptions = require('../lib/options/SchemaStringOptions');
+    const keys = Object.keys(SchemaStringOptions.prototype).
+      filter(key => key !== 'constructor');
+    const functions = Object.keys(Schema.Types.String.prototype).
+      filter(key => !['constructor', 'cast', 'castForQuery', 'checkRequired'].includes(key));
+    assert.deepEqual(keys.sort(), functions.sort());
+  });
 });

From fab4f5d80e8b701b6a4f3a86e7976a9588c897cd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Oct 2019 16:21:40 -0400
Subject: [PATCH 0106/2348] test(schema): fix tests on node v4 and v5

---
 test/schema.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 7b4d6435c87..23ecf032ba4 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2141,7 +2141,7 @@ describe('schema', function() {
     const keys = Object.keys(SchemaStringOptions.prototype).
       filter(key => key !== 'constructor');
     const functions = Object.keys(Schema.Types.String.prototype).
-      filter(key => !['constructor', 'cast', 'castForQuery', 'checkRequired'].includes(key));
+      filter(key => ['constructor', 'cast', 'castForQuery', 'checkRequired'].indexOf(key) === -1);
     assert.deepEqual(keys.sort(), functions.sort());
   });
 });

From 5656b4e224d3834e5c6447026972948575f86411 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Oct 2019 16:53:52 -0400
Subject: [PATCH 0107/2348] chore: release 5.7.6

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 4542f383577..29b01b9bbdd 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.7.6 / 2019-10-21
+==================
+ * fix: upgrade mongodb driver -> 3.3.3 to fix issue with failing to connect to a replica set if one member is down #8209
+ * fix(document): fix TypeError when setting a single nested subdoc with timestamps #8251
+ * fix(cursor): fix issue with long-running `eachAsync()` cursor #8249 #8235
+ * fix(connection): ensure repeated `close` events from useUnifiedTopology don't disconnect Mongoose from replica set #8224
+ * fix(document): support calling `Document` constructor directly in Node.js #8237
+ * fix(populate): add document array subpaths to parent doc `populated()` when calling `DocumentArray#push()` #8247
+ * fix(options): add missing minlength and maxlength to SchemaStringOptions #8256
+ * docs: add documentarraypath to API docs, including DocumentArrayPath#discriminator() #8164
+ * docs(schematypes): add a section about the `type` property #8227
+ * docs(api): fix Connection.close return param #8258 [gosuhiman](https://github.com/gosuhiman)
+ * docs: update link to broken image on home page #8253 [krosenk729](https://github.com/krosenk729)
+
 5.7.5 / 2019-10-14
 ==================
  * fix(query): delete top-level `_bsontype` property in queries to prevent silent empty queries #8222
diff --git a/package.json b/package.json
index c7abe077205..7f1154227cf 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.6-pre",
+  "version": "5.7.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 068e57ab89a56a28f2a21b18243d83f179e4c2f2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Oct 2019 10:14:41 -0400
Subject: [PATCH 0108/2348] chore: now working on 5.7.7

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 7f1154227cf..2ab6b11dc6b 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.6",
+  "version": "5.7.7-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From d7ceb89af728e06e9fc7b68b424725502e8b4286 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Oct 2019 10:17:24 -0400
Subject: [PATCH 0109/2348] test(query): repro #8268

---
 test/query.test.js | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index f15cdb07ba0..e670d3016cd 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3569,12 +3569,18 @@ describe('Query', function() {
     });
   });
 
-  it('query with top-level _bsontype (gh-8222)', function() {
+  it('query with top-level _bsontype (gh-8222) (gh-8268)', function() {
     const userSchema = Schema({ token: String });
     const User = db.model('gh8222', userSchema);
 
-    return User.create({ token: 'rightToken' }).
-      then(() => User.findOne({ token: 'wrongToken', _bsontype: 'a' })).
-      then(doc => assert.ok(!doc));
+    return co(function*() {
+      const original = yield User.create({ token: 'rightToken' });
+      let doc = yield User.findOne({ token: 'wrongToken', _bsontype: 'a' });
+      assert.ok(!doc);
+
+      doc = yield User.findOne(original._id);
+      assert.ok(doc);
+      assert.equal(doc.token, 'rightToken');
+    });
   });
 });

From b03faf5ceec529c13b17684b8bf250b2b451b060 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Oct 2019 10:21:37 -0400
Subject: [PATCH 0110/2348] fix(query): allow findOne(objectid) and
 find(objectid)

Fix #8268
---
 lib/cast.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/cast.js b/lib/cast.js
index 3dfd651acd2..94bdb1d2b9e 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -28,8 +28,10 @@ module.exports = function cast(schema, obj, options, context) {
   }
 
   // bson 1.x has the unfortunate tendency to remove filters that have a top-level
-  // `_bsontype` property. Should remove this when we upgrade to bson 4.x. See gh-8222
-  if (obj.hasOwnProperty('_bsontype')) {
+  // `_bsontype` property. But we should still allow ObjectIds because
+  // `Collection#find()` has a special case to support `find(objectid)`.
+  // Should remove this when we upgrade to bson 4.x. See gh-8222, gh-8268
+  if (obj.hasOwnProperty('_bsontype') && obj._bsontype !== 'ObjectID') {
     delete obj._bsontype;
   }
 

From ecd82425d98c90035a11e7eec880e471d41f0afd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Oct 2019 11:05:28 -0400
Subject: [PATCH 0111/2348] docs(query): make note that `filter` param to
 `find()` can be an ObjectId re: #8268

---
 lib/model.js | 2 +-
 lib/query.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 0982d97788c..377b6df40e2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1963,7 +1963,7 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
  *     var promise = query.exec();
  *     promise.addBack(function (err, docs) {});
  *
- * @param {Object} filter
+ * @param {Object|ObjectId} filter
  * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](http://mongoosejs.com/docs/api.html#query_Query-select)
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Function} [callback]
diff --git a/lib/query.js b/lib/query.js
index 714ceb38c54..370d5add3e9 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1941,7 +1941,7 @@ Query.prototype._find = wrapThunk(function(callback) {
  *     // Using callbacks
  *     Movie.find({ year: { $gte: 1980, $lte: 1989 } }, function(err, arr) {});
  *
- * @param {Object} [filter] mongodb selector. If not specified, returns all documents.
+ * @param {Object|ObjectId} [filter] mongodb selector. If not specified, returns all documents.
  * @param {Function} [callback]
  * @return {Query} this
  * @api public

From ca4f52b29ce4cbca7c1f5e48e8e367eaf8cbd94a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Oct 2019 15:08:04 -0400
Subject: [PATCH 0112/2348] test(populate): repro #8230

---
 test/model.populate.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 0ab15770983..96f7425f2e9 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8345,6 +8345,31 @@ describe('model: populate:', function() {
     });
   });
 
+  it('sets populate virtual to empty array if local field empty (gh-8230)', function() {
+    const GroupSchema = new Schema({
+      roles: [{
+        roleId: String
+      }]
+    });
+    GroupSchema.virtual('roles$', {
+      ref: 'gh8230_Role',
+      localField: 'roles.roleId',
+      foreignField: '_id'
+    });
+
+    const RoleSchema = new Schema({});
+
+    const GroupModel = db.model('gh8230_Group', GroupSchema);
+    db.model('gh8230_Role', RoleSchema);
+
+    return co(function*() {
+      yield GroupModel.create({ roles: [] });
+
+      const res = yield GroupModel.findOne({}).populate('roles$');
+      assert.deepEqual(res.roles$, []);
+    });
+  });
+
   it('sets populate virtual with count to 0 if local field empty (gh-7731)', function() {
     const GroupSchema = new Schema({
       roles: [{

From f4bd46389aa768fd923b8502c62cb1173f118185 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Oct 2019 15:10:09 -0400
Subject: [PATCH 0113/2348] fix(populate): make populate virtual consistently
 an empty array if local field is only empty arrays

Fix #8230
---
 lib/model.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 377b6df40e2..2df50420e98 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4120,10 +4120,11 @@ function populate(model, docs, options, callback) {
     assignmentOpts.excludeId = excludeIdReg.test(select) || (select && select._id === 0);
 
     if (ids.length === 0 || ids.every(utils.isNullOrUndefined)) {
-      // Ensure that we set populate virtuals with count option to 0 even
-      // if we don't actually execute a query.
+      // Ensure that we set populate virtuals to 0 or empty array even
+      // if we don't actually execute a query because they don't have
+      // a value by default. See gh-7731, gh-8230
       --_remaining;
-      if (mod.count) {
+      if (mod.count || mod.isVirtual) {
         _assign(model, [], mod, assignmentOpts);
       }
       continue;

From 28e8ac4cf59ba0254372d43ecaa941ae32500784 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Oct 2019 14:34:02 -0400
Subject: [PATCH 0114/2348] chore: release 5.7.7

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 29b01b9bbdd..5b58e4216a8 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.7.7 / 2019-10-24
+==================
+ * fix(populate): make populate virtual consistently an empty array if local field is only empty arrays #8230
+ * fix(query): allow findOne(objectid) and find(objectid) #8268
+
 5.7.6 / 2019-10-21
 ==================
  * fix: upgrade mongodb driver -> 3.3.3 to fix issue with failing to connect to a replica set if one member is down #8209
diff --git a/package.json b/package.json
index 2ab6b11dc6b..aa30726e35e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.7-pre",
+  "version": "5.7.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 987f15d8fe1ed43dcb2a4ee1b40f73a42e0b2230 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 25 Oct 2019 09:39:34 -0400
Subject: [PATCH 0115/2348] chore: now working on 5.7.8

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index aa30726e35e..c7a3e78cfc4 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.7",
+  "version": "5.7.8-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 0db3f1f1ea682c945f8188463f2477d12eea60e7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 26 Oct 2019 11:21:10 -0400
Subject: [PATCH 0116/2348] test(cursor): make query cursor test more robust to
 timing delays

Fix #8266
---
 test/query.cursor.test.js | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 9a86249db5f..e4808b624c7 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -319,22 +319,21 @@ describe('QueryCursor', function() {
       const cursor = Model.find().sort({ name: 1 }).cursor();
 
       const names = [];
-      const startedAt = [];
+      const resolves = [];
       const checkDoc = function(doc) {
         names.push(doc.name);
-        startedAt.push(Date.now());
-        return {
-          then: function(resolve) {
-            setTimeout(function() {
-              resolve();
-            }, 100);
-          }
-        };
+        const p = new Promise(resolve => {
+          resolves.push(resolve);
+        });
+
+        if (names.length === 2) {
+          setTimeout(() => resolves.forEach(r => r()), 0);
+        }
+
+        return p;
       };
       cursor.eachAsync(checkDoc, { parallel: 2 }).then(function() {
-        assert.ok(Date.now() - startedAt[1] >= 100);
-        assert.equal(startedAt.length, 2);
-        assert.ok(startedAt[1] - startedAt[0] < 50);
+        assert.equal(names.length, 2);
         assert.deepEqual(names.sort(), ['Axl', 'Slash']);
         done();
       }).catch(done);

From 95490157f105e6d672744105cc1028ccd7e4d72f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 26 Oct 2019 12:10:28 -0400
Subject: [PATCH 0117/2348] fix(populate): update top-level `populated()` when
 updating document array with populated subpaths

Fix #8265
---
 lib/types/core_array.js     | 18 ---------
 lib/types/documentarray.js  | 81 +++++++++++++++++++++++++++++++++++++
 test/model.populate.test.js | 14 ++++++-
 3 files changed, 94 insertions(+), 19 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 92121d9a523..e9f2a54e799 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -634,24 +634,6 @@ class CoreMongooseArray extends Array {
       undefined, { skipDocumentArrayCast: true });
     const ret = [].push.apply(this, values);
 
-    // If this is a document array, each element may contain single
-    // populated paths, so we need to modify the top-level document's
-    // populated cache. See gh-8247.
-    if (this.isMongooseDocumentArray && parent.$__.populated != null) {
-      const populatedPaths = Object.keys(parent.$__.populated).
-        filter(p => p.startsWith(this[arrayPathSymbol] + '.'));
-
-      for (const path of populatedPaths) {
-        const remnant = path.slice((this[arrayPathSymbol] + '.').length);
-        if (!Array.isArray(parent.$__.populated[path].value)) {
-          continue;
-        }
-        for (const val of values) {
-          parent.$__.populated[path].value.push(val.populated(remnant));
-        }
-      }
-    }
-
     this._registerAtomic('$push', values);
     this._markModified();
     return ret;
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index afa2586bd5e..cc6f5d6d77f 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -172,6 +172,64 @@ class CoreDocumentArray extends CoreMongooseArray {
     }));
   }
 
+  /**
+   * Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking.
+   *
+   * @param {Object} [args...]
+   * @api public
+   * @method push
+   * @memberOf MongooseDocumentArray
+   */
+
+  push() {
+    const ret = super.push.apply(this, arguments);
+
+    _updateParentPopulated(this);
+
+    return ret;
+  }
+
+  /**
+   * Pulls items from the array atomically.
+   *
+   * @param {Object} [args...]
+   * @api public
+   * @method pull
+   * @memberOf MongooseDocumentArray
+   */
+
+  pull() {
+    const ret = super.pull.apply(this, arguments);
+
+    _updateParentPopulated(this);
+
+    return ret;
+  }
+
+  /**
+   * Wraps [`Array#shift`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/unshift) with proper change tracking.
+   */
+
+  shift() {
+    const ret = super.shift.apply(this, arguments);
+
+    _updateParentPopulated(this);
+
+    return ret;
+  }
+
+  /**
+   * Wraps [`Array#splice`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/splice) with proper change tracking and casting.
+   */
+
+  splice() {
+    const ret = super.splice.apply(this, arguments);
+
+    _updateParentPopulated(this);
+
+    return ret;
+  }
+
   /**
    * Helper for console.log
    *
@@ -254,6 +312,29 @@ if (util.inspect.custom) {
     CoreDocumentArray.prototype.inspect;
 }
 
+/*!
+ * If this is a document array, each element may contain single
+ * populated paths, so we need to modify the top-level document's
+ * populated cache. See gh-8247, gh-8265.
+ */
+
+function _updateParentPopulated(arr) {
+  const parent = arr[arrayParentSymbol];
+  if (parent.$__.populated != null) {
+    const populatedPaths = Object.keys(parent.$__.populated).
+      filter(p => p.startsWith(arr[arrayPathSymbol] + '.'));
+
+    for (const path of populatedPaths) {
+      const remnant = path.slice((arr[arrayPathSymbol] + '.').length);
+      if (!Array.isArray(parent.$__.populated[path].value)) {
+        continue;
+      }
+
+      parent.$__.populated[path].value = arr.map(val => val.populated(remnant));
+    }
+  }
+}
+
 /**
  * DocumentArray constructor
  *
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 96f7425f2e9..0ca10658838 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8727,7 +8727,7 @@ describe('model: populate:', function() {
       });
     });
 
-    it('updates top-level populated() when pushing elements onto a document array with single populated path (gh-8247)', function() {
+    it('updates top-level populated() when pushing elements onto a document array with single populated path (gh-8247) (gh-8265)', function() {
       return co(function*() {
         const docs = yield Author.create([
           { name: 'test1' },
@@ -8747,6 +8747,14 @@ describe('model: populate:', function() {
         assert.equal(pop[0].toHexString(), docs[0]._id.toHexString());
         assert.equal(pop[1], null);
 
+        fromDb.comments.pull({ _id: fromDb.comments[1]._id });
+        pop = fromDb.populated('comments.author');
+        assert.equal(pop.length, 1);
+
+        fromDb.comments.shift();
+        pop = fromDb.populated('comments.author');
+        assert.equal(pop.length, 0);
+
         // And try setting to populated path
         fromDb = yield Page.findOne().populate('comments.author');
         assert.ok(Array.isArray(fromDb.populated('comments.author')));
@@ -8756,6 +8764,10 @@ describe('model: populate:', function() {
         fromDb.comments.push({ author: docs[1] });
         pop = fromDb.populated('comments.author');
         assert.equal(pop.length, 2);
+
+        fromDb.comments.splice(1, 1);
+        pop = fromDb.populated('comments.author');
+        assert.equal(pop.length, 1);
       });
     });
   });

From 7dbf96c801400b07c7f2ecb06e5affaee2f86db5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Oct 2019 13:05:15 -0400
Subject: [PATCH 0118/2348] refactor(schema): create separate schematype for
 DocumentArrayPaths instead of ad-hoc within `getPositionalPath()`

Re: #6405
---
 lib/schema.js               | 11 +----------
 lib/schema/documentarray.js | 12 ++++++++++++
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 17a1c0da466..0745cc416fd 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1179,16 +1179,7 @@ function getPositionalPathType(self, path) {
 
     if (i === last && val && !/\D/.test(subpath)) {
       if (val.$isMongooseDocumentArray) {
-        const oldVal = val;
-        val = new SchemaType(subpath, {
-          required: get(val, 'schemaOptions.required', false)
-        });
-        val.cast = function(value, doc, init) {
-          return oldVal.cast(value, doc, init)[0];
-        };
-        val.$isMongooseDocumentArrayElement = true;
-        val.caster = oldVal.caster;
-        val.schema = oldVal.schema;
+        val = val.$embeddedSchemaType;
       } else if (val instanceof MongooseTypes.Array) {
         // StringSchema, NumberSchema, etc
         val = val.caster;
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 4bacffd3630..c39f425a86c 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -9,6 +9,7 @@ const CastError = require('../error/cast');
 const EventEmitter = require('events').EventEmitter;
 const SchemaType = require('../schematype');
 const discriminator = require('../helpers/model/discriminator');
+const get = require('../helpers/get');
 const util = require('util');
 const utils = require('../utils');
 const getConstructor = require('../helpers/discriminator/getConstructor');
@@ -54,6 +55,17 @@ function DocumentArrayPath(key, schema, options, schemaOptions) {
       return arr;
     });
   }
+
+  const parentSchemaType = this; /* eslint consistent-this: 0 */
+  this.$embeddedSchemaType = new SchemaType(key + '.$', {
+    required: get(this, 'schemaOptions.required', false)
+  });
+  this.$embeddedSchemaType.cast = function(value, doc, init) {
+    return parentSchemaType.cast(value, doc, init)[0];
+  };
+  this.$embeddedSchemaType.$isMongooseDocumentArrayElement = true;
+  this.$embeddedSchemaType.caster = this.Constructor;
+  this.$embeddedSchemaType.schema = this.schema;
 }
 
 /**

From 0d057fef2493914291c493b236808a996e5e46fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 28 Oct 2019 15:45:57 -0400
Subject: [PATCH 0119/2348] docs(model): remove unnecessary *

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 2df50420e98..c8c9f3e961c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1149,7 +1149,7 @@ for (const i in EventEmitter.prototype) {
  *
  * Mongoose calls this function automatically when a model is created using
  * [`mongoose.model()`](/docs/api.html#mongoose_Mongoose-model) or
- * * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
+ * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
  * don't need to call it. This function is also idempotent, so you may call it
  * to get back a promise that will resolve when your indexes are finished
  * building as an alternative to [`MyModel.on('index')`](/docs/guide.html#indexes)

From 78d5c4b707f925642db2c3e58ad6a46d7f8a46cf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Oct 2019 22:25:29 -0400
Subject: [PATCH 0120/2348] test: repro #8274

---
 test/model.discriminator.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index eb25e0a3939..f8b9342c392 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1485,5 +1485,28 @@ describe('model', function() {
       assert.equal(e.get('lookups.0.name'), 'address2');
       assert.equal(e.lookups[0].name, 'address2');
     });
+
+    it('_id: false in discriminator nested schema (gh-8274)', function() {
+      const schema = new Schema({
+        operations: {
+          type: [{ _id: Number, action: String }]
+        }
+      });
+      schema.path('operations').discriminator('gh8274_test', new Schema({
+        pitchPath: Schema({
+          _id: Number,
+          path: [{ _id: false, x: Number, y: Number }]
+        })
+      }));
+      const Model = db.model('gh8274', schema);
+
+      const doc = new Model();
+      doc.operations.push({
+        _id: 42,
+        __t: 'gh8274_test',
+        pitchPath: { path: [{ x: 1, y: 2 }] }
+      });
+      assert.strictEqual(doc.operations[0].pitchPath.path[0]._id, void 0);
+    });
   });
 });

From 7dd63fd54be86d9890c26750874c1330c501f9ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Oct 2019 22:28:30 -0400
Subject: [PATCH 0121/2348] fix(schema): retain `_id: false` in schema after
 nesting in another schema

Fix #8274
---
 lib/schema.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 0745cc416fd..a1cd4618ec8 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -402,7 +402,6 @@ Schema.prototype.add = function add(obj, prefix) {
   // the `_id` option. This behavior never worked before 5.4.11 but numerous
   // codebases use it (see gh-7516, gh-7512).
   if (obj._id === false && prefix == null) {
-    delete obj._id;
     this.options._id = false;
   }
 
@@ -417,6 +416,10 @@ Schema.prototype.add = function add(obj, prefix) {
       throw new TypeError('Invalid value for schema path `' + fullPath +
         '`, got value "' + obj[key] + '"');
     }
+    // Retain `_id: false` but don't set it as a path, re: gh-8274.
+    if (key === '_id' && obj[key] === false) {
+      continue;
+    }
 
     if (Array.isArray(obj[key]) && obj[key].length === 1 && obj[key][0] == null) {
       throw new TypeError('Invalid value for schema Array path `' + fullPath +

From 5b6eeab41d98a8f88c2dfe7489a4a38710f9f5cc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 31 Oct 2019 10:48:34 -0400
Subject: [PATCH 0122/2348] docs: clarify that transforms defined in
 `toObject()` options are applied to subdocs

Fix #8260
---
 lib/document.js | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 23c30db1ce0..b82c31196ba 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2970,7 +2970,6 @@ Document.prototype.$toObject = function(options, json) {
  *
  * If you want to skip transformations, use `transform: false`:
  *
- *     if (!schema.options.toObject) schema.options.toObject = {};
  *     schema.options.toObject.hide = '_id';
  *     schema.options.toObject.transform = function (doc, ret, options) {
  *       if (options.hide) {
@@ -2986,7 +2985,26 @@ Document.prototype.$toObject = function(options, json) {
  *     doc.toObject({ hide: 'secret _id', transform: false });// { _id: 'anId', secret: 47, name: 'Wreck-it Ralph' }
  *     doc.toObject({ hide: 'secret _id', transform: true }); // { name: 'Wreck-it Ralph' }
  *
- * Transforms are applied _only to the document and are not applied to sub-documents_.
+ * If you pass a transform in `toObject()` options, Mongoose will apply the transform
+ * to [subdocuments](/docs/subdocs.html) in addition to the top-level document.
+ * Similarly, `transform: false` skips transforms for all subdocuments.
+ * Note that this is behavior is different for transforms defined in the schema:
+ * if you define a transform in `schema.options.toObject.transform`, that transform
+ * will **not** apply to subdocuments.
+ *
+ *     const memberSchema = new Schema({ name: String, email: String });
+ *     const groupSchema = new Schema({ members: [memberSchema], name: String, email });
+ *     const Group = mongoose.model('Group', groupSchema);
+ *
+ *     const doc = new Group({
+ *       name: 'Engineering',
+ *       email: 'dev@mongoosejs.io',
+ *       members: [{ name: 'Val', email: 'val@mongoosejs.io' }]
+ *     });
+ *
+ *     // Removes `email` from both top-level document **and** array elements
+ *     // { name: 'Engineering', members: [{ name: 'Val' }] }
+ *     doc.toObject({ transform: (doc, ret) => { delete ret.email; return ret; } });
  *
  * Transforms, like all of these options, are also available for `toJSON`. See [this guide to `JSON.stringify()`](https://thecodebarbarian.com/the-80-20-guide-to-json-stringify-in-javascript.html) to learn why `toJSON()` and `toObject()` are separate functions.
  *

From 374246d907b2c5ccee4a400ee2ad018a9140d981 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 1 Nov 2019 22:35:59 -0400
Subject: [PATCH 0123/2348] docs(connection): add note about exporting schemas,
 not models, in multi connection paradigm

Fix #8275
---
 docs/connections.pug | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/docs/connections.pug b/docs/connections.pug
index 1335e39e515..7a4e6bd7e97 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -323,6 +323,35 @@ block content
     create and retrieve [models](./api.html#model_Model). Models are
     **always** scoped to a single connection.
 
+    ```javascript
+    const UserModel = conn.model('User', userSchema);
+    ```
+
+    If you use multiple connections, you should make sure you export schemas,
+    **not** models.
+
+    ```javascript
+    const userSchema = new Schema({ name: String, email: String });
+
+    // The correct pattern is to export a schema
+    module.exports = userSchema;
+
+    // Because if you export a model as shown below, the model will be scoped
+    // to Mongoose's default connection.
+    // module.exports = mongoose.model('User', userSchema);
+    ```
+
+    In addition, you should define a factory function that registers models on a
+    connection to make it easy to register all your models on a given connection.
+
+    ```javascript
+    const userSchema = require('./userSchema');
+
+    module.exports = conn => {
+      conn.model('User', userSchema);
+    };
+    ```
+
     Mongoose creates a _default connection_ when you call `mongoose.connect()`.
     You can access the default connection using `mongoose.connection`.
 

From b86749e94e1dd1a7a74b99802a87baf95348846b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 Nov 2019 17:44:00 -0400
Subject: [PATCH 0124/2348] fix(document): make Document class an event emitter
 to support defining documents without models in node

Fix #8272
---
 lib/document.js       | 4 ++++
 test/document.test.js | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index b82c31196ba..f2de3f099a1 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -184,6 +184,10 @@ utils.each(
 
 Document.prototype.constructor = Document;
 
+for (const i in EventEmitter.prototype) {
+  Document[i] = EventEmitter.prototype[i];
+}
+
 /**
  * The documents schema.
  *
diff --git a/test/document.test.js b/test/document.test.js
index c1e3e796f07..1643cab63ee 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -136,6 +136,8 @@ describe('document', function() {
       assert.ok(!myUserDoc.name);
       myUserDoc.name = 123;
       assert.strictEqual(myUserDoc.name, '123');
+
+      assert.ifError(myUserDoc.validateSync());
     });
   });
 

From dfde779139a41820ddfb55dc7f088636e80e9f0f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 3 Nov 2019 13:41:00 -0500
Subject: [PATCH 0125/2348] fix(document): allow manually populating path
 within document array

Fix #8273
---
 lib/document.js                  | 14 ++++++++++++++
 lib/schematype.js                |  2 +-
 lib/types/documentarray.js       |  2 +-
 test/model.discriminator.test.js | 32 ++++++++++++++++++++++++++++++++
 4 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f2de3f099a1..9afbfea2eb4 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1167,6 +1167,20 @@ Document.prototype.$set = function $set(path, val, type, options) {
       val = schema.applySetters(val, this, false, priorVal);
     }
 
+    if (schema.$isMongooseDocumentArray &&
+        Array.isArray(val) &&
+        val.length > 0 &&
+        val[0].$__ != null &&
+        val[0].$__.populated != null) {
+      const populatedPaths = Object.keys(val[0].$__.populated);
+      for (const populatedPath of populatedPaths) {
+        this.populated(path + '.' + populatedPath,
+          val.map(v => v.populated(populatedPath)),
+          val[0].$__.populated[populatedPath].options);
+      }
+      didPopulate = true;
+    }
+
     if (!didPopulate && this.$__.populated) {
       delete this.$__.populated[path];
     }
diff --git a/lib/schematype.js b/lib/schematype.js
index ed5b6738ec0..2ad0e3d4349 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1265,7 +1265,7 @@ SchemaType._isRef = function(self, value, doc, init) {
     // - setting / pushing values after population
     const path = doc.$__fullPath(self.path);
     const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
-    ref = owner.populated(path);
+    ref = owner.populated(path) || doc.populated(self.path);
   }
 
   if (ref) {
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index cc6f5d6d77f..3f74cf2d2ee 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -86,7 +86,7 @@ class CoreDocumentArray extends CoreMongooseArray {
         }
       }
     }
-
+    
     if (Constructor.$isMongooseDocumentArray) {
       return Constructor.cast(value, this, undefined, undefined, index);
     }
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index f8b9342c392..1b50f81a201 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1508,5 +1508,37 @@ describe('model', function() {
       });
       assert.strictEqual(doc.operations[0].pitchPath.path[0]._id, void 0);
     });
+
+    it('with discriminators in embedded arrays (gh-8273)', function(done) {
+      const ProductSchema = new Schema({
+        title: String
+      });
+      const Product = mongoose.model('gh8273_Product', ProductSchema);
+      const ProductItemSchema = new Schema({
+        product: { type: Schema.Types.ObjectId, ref: 'gh8273_Product' }
+      });
+
+      const OrderItemSchema = new Schema({}, {discriminatorKey: '__t'});
+
+      const OrderSchema = new Schema({
+        items: [OrderItemSchema],
+      });
+
+      OrderSchema.path('items').discriminator('ProductItem', ProductItemSchema);
+      const Order = mongoose.model('Order', OrderSchema);
+
+      const product = new Product({title: 'Product title'});
+
+      const order = new Order({
+        items: [{
+          __t: 'ProductItem',
+          product: product
+        }]
+      });
+      assert.ok(order.items[0].product.title);
+      assert.equal(order.populated('items.product').length, 1);
+
+      done();
+    });
   });
 });

From c1e49c3a1d281095536896cdd0534edc18e52511 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 3 Nov 2019 13:49:27 -0500
Subject: [PATCH 0126/2348] test: fix tests re: #8273

---
 lib/document.js            | 1 +
 lib/types/documentarray.js | 2 +-
 test/model.update.test.js  | 8 +++-----
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 9afbfea2eb4..6213508261d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1170,6 +1170,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
     if (schema.$isMongooseDocumentArray &&
         Array.isArray(val) &&
         val.length > 0 &&
+        val[0] != null &&
         val[0].$__ != null &&
         val[0].$__.populated != null) {
       const populatedPaths = Object.keys(val[0].$__.populated);
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 3f74cf2d2ee..cc6f5d6d77f 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -86,7 +86,7 @@ class CoreDocumentArray extends CoreMongooseArray {
         }
       }
     }
-    
+
     if (Constructor.$isMongooseDocumentArray) {
       return Constructor.cast(value, this, undefined, undefined, index);
     }
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 961409fbb08..a504a893525 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -2510,7 +2510,7 @@ describe('model: update:', function() {
         catch(done);
     });
 
-    it('$pullAll with null (gh-5164)', function(done) {
+    it('$pullAll with null (gh-5164)', function() {
       const schema = new Schema({
         name: String,
         arr: [{ name: String }]
@@ -2519,7 +2519,7 @@ describe('model: update:', function() {
 
       const doc = new Test({ name: 'Test', arr: [null, {name: 'abc'}] });
 
-      doc.save().
+      return doc.save().
         then(function(doc) {
           return Test.update({ _id: doc._id }, {
             $pullAll: { arr: [null] }
@@ -2531,9 +2531,7 @@ describe('model: update:', function() {
         then(function(doc) {
           assert.equal(doc.arr.length, 1);
           assert.equal(doc.arr[0].name, 'abc');
-          done();
-        }).
-        catch(done);
+        });
     });
 
     it('$set array (gh-5403)', function(done) {

From 69bf575b7ddc194580df9096dfaf2d108e46e76c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 3 Nov 2019 14:45:16 -0500
Subject: [PATCH 0127/2348] docs(aggregate): make aggregation Symbol.iterator
 docs actually use aggregate()

Re: #8280
---
 lib/aggregate.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index a1615df41b2..b9d08af3181 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -1011,20 +1011,20 @@ Aggregate.prototype.catch = function(reject) {
 
 /**
  * Returns an asyncIterator for use with [`for/await/of` loops](http://bit.ly/async-iterators)
- * This function *only* works for `find()` queries.
  * You do not need to call this function explicitly, the JavaScript runtime
  * will call it for you.
  *
  * ####Example
  *
- *     for await (const doc of Model.find().sort({ name: 1 })) {
+ *     const agg = Model.aggregate([{ $match: { age: { $gte: 25 } } }]);
+ *     for await (const doc of agg) {
  *       console.log(doc.name);
  *     }
  *
  * Node.js 10.x supports async iterators natively without any flags. You can
  * enable async iterators in Node.js 8.x using the [`--harmony_async_iteration` flag](https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187).
  *
- * **Note:** This function is not if `Symbol.asyncIterator` is undefined. If
+ * **Note:** This function is not set if `Symbol.asyncIterator` is undefined. If
  * `Symbol.asyncIterator` is undefined, that means your Node.js version does not
  * support async iterators.
  *

From 4c090c53fa0c4f381c1fa181c7aa85c47172ee2d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 3 Nov 2019 14:45:46 -0500
Subject: [PATCH 0128/2348] fix(cursor): throw error when using aggregation
 cursor as async iterator

Fix #8280
---
 lib/cursor/AggregationCursor.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 45acc94d4a8..03b6912464a 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -4,6 +4,7 @@
 
 'use strict';
 
+const MongooseError = require('../error/mongooseError');
 const Readable = require('stream').Readable;
 const eachAsync = require('../helpers/cursor/eachAsync');
 const util = require('util');
@@ -94,6 +95,15 @@ AggregationCursor.prototype._read = function() {
   });
 };
 
+if (Symbol.asyncIterator != null) {
+  const msg = 'Mongoose does not support using async iterators with an ' +
+    'existing aggregation cursor. See http://bit.ly/mongoose-async-iterate-aggregation';
+
+  AggregationCursor.prototype[Symbol.asyncIterator] = function() {
+    throw new MongooseError(msg);
+  };
+}
+
 /**
  * Registers a transform function which subsequently maps documents retrieved
  * via the streams interface or `.next()`

From 2694cbd1e7746f9561c4310cba43206a2c8cf62f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 3 Nov 2019 15:12:44 -0500
Subject: [PATCH 0129/2348] docs: document return types for `.discriminator()`

Fix #8287
---
 lib/model.js                   | 3 ++-
 lib/queryhelpers.js            | 2 +-
 lib/schema/SingleNestedPath.js | 1 +
 lib/schema/documentarray.js    | 1 +
 4 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index c8c9f3e961c..b95f4ad3bf2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1067,6 +1067,7 @@ Model.exists = function exists(filter, options, callback) {
  * @param {String} name discriminator model name
  * @param {Schema} schema discriminator model schema
  * @param {String} [value] the string stored in the `discriminatorKey` property. If not specified, Mongoose uses the `name` parameter.
+ * @return {Model} The newly created discriminator model
  * @api public
  */
 
@@ -3411,7 +3412,7 @@ Model.bulkWrite = function(ops, options, callback) {
  *     var mongooseCandy = Candy.hydrate({ _id: '54108337212ffb6d459f854c', type: 'jelly bean' });
  *
  * @param {Object} obj
- * @return {Model} document instance
+ * @return {Document} document instance
  * @api public
  */
 
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 10bfd9bd777..045354f0f84 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -107,7 +107,7 @@ exports.getDiscriminatorByValue = getDiscriminatorByValue;
  * @param {Object} doc
  * @param {Object} fields
  *
- * @return {Model}
+ * @return {Document}
  */
 exports.createModel = function createModel(model, doc, fields, userProvidedFields) {
   model.hooks.execPreSync('createModel', doc);
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 00032ad793e..ec7b8df6dbb 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -280,6 +280,7 @@ SingleNestedPath.prototype.doValidateSync = function(value, scope, options) {
  * @param {String} name
  * @param {Schema} schema fields to add to the schema for instances of this sub-class
  * @param {String} [value] the string stored in the `discriminatorKey` property. If not specified, Mongoose uses the `name` parameter.
+ * @return {Function} the constructor Mongoose will use for creating instances of this discriminator model
  * @see discriminators /docs/discriminators.html
  * @api public
  */
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index c39f425a86c..4f8cbb026d3 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -147,6 +147,7 @@ function _createConstructor(schema, options, baseClass) {
  * @param {Schema} schema fields to add to the schema for instances of this sub-class
  * @param {String} [value] the string stored in the `discriminatorKey` property. If not specified, Mongoose uses the `name` parameter.
  * @see discriminators /docs/discriminators.html
+ * @return {Function} the constructor Mongoose will use for creating instances of this discriminator model
  * @api public
  */
 

From b3c95de17c79f95a9b2fbf1bdd8774be118f759f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 4 Nov 2019 10:04:59 -0500
Subject: [PATCH 0130/2348] docs: add links to clarify truthy/falsy

---
 lib/options/SchemaTypeOptions.js | 15 ++++++++++-----
 lib/schema.js                    |  4 ++--
 lib/schematype.js                |  2 +-
 3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 3dfff15665e..eef74f6829f 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -107,7 +107,8 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'ref', opts);
 Object.defineProperty(SchemaTypeOptions.prototype, 'select', opts);
 
 /**
- * If truthy, Mongoose will build an index on this path when the model is
+ * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
+ * build an index on this path when the model is
  * compiled.
  *
  * @api public
@@ -120,7 +121,8 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'select', opts);
 Object.defineProperty(SchemaTypeOptions.prototype, 'index', opts);
 
 /**
- * If truthy, Mongoose will build a unique index on this path when the
+ * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose
+ * will build a unique index on this path when the
  * model is compiled. [The `unique` option is **not** a validator](/docs/validation.html#the-unique-option-is-not-a-validator).
  *
  * @api public
@@ -133,7 +135,8 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'index', opts);
 Object.defineProperty(SchemaTypeOptions.prototype, 'unique', opts);
 
 /**
- * If truthy, Mongoose will disallow changes to this path once the document
+ * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
+ * disallow changes to this path once the document
  * is saved to the database for the first time. Read more about [immutability in Mongoose here](http://thecodebarbarian.com/whats-new-in-mongoose-5-6-immutable-properties.html).
  *
  * @api public
@@ -146,7 +149,8 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'unique', opts);
 Object.defineProperty(SchemaTypeOptions.prototype, 'immutable', opts);
 
 /**
- * If truthy, Mongoose will build a sparse index on this path.
+ * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
+ * build a sparse index on this path.
  *
  * @api public
  * @property sparse
@@ -158,7 +162,8 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'immutable', opts);
 Object.defineProperty(SchemaTypeOptions.prototype, 'sparse', opts);
 
 /**
- * If truthy, Mongoose will build a text index on this path.
+ * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose
+ * will build a text index on this path.
  *
  * @api public
  * @property text
diff --git a/lib/schema.js b/lib/schema.js
index a1cd4618ec8..00acac49b2f 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1631,8 +1631,8 @@ Schema.prototype.indexes = function() {
  * @param {String|Model} [options.ref] model name or model instance. Marks this as a [populate virtual](populate.html#populate-virtuals).
  * @param {String|Function} [options.localField] Required for populate virtuals. See [populate virtual docs](populate.html#populate-virtuals) for more information.
  * @param {String|Function} [options.foreignField] Required for populate virtuals. See [populate virtual docs](populate.html#populate-virtuals) for more information.
- * @param {Boolean|Function} [options.justOne=false] Only works with populate virtuals. If truthy, will be a single doc or `null`. Otherwise, the populate virtual will be an array.
- * @param {Boolean} [options.count=false] Only works with populate virtuals. If truthy, this populate virtual will contain the number of documents rather than the documents themselves when you `populate()`.
+ * @param {Boolean|Function} [options.justOne=false] Only works with populate virtuals. If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), will be a single doc or `null`. Otherwise, the populate virtual will be an array.
+ * @param {Boolean} [options.count=false] Only works with populate virtuals. If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), this populate virtual will contain the number of documents rather than the documents themselves when you `populate()`.
  * @return {VirtualType}
  */
 
diff --git a/lib/schematype.js b/lib/schematype.js
index 2ad0e3d4349..5b3e918036b 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -664,7 +664,7 @@ SchemaType.prototype.get = function(fn) {
  *     Product.on('error', handleError);
  *
  * @param {RegExp|Function|Object} obj validator function, or hash describing options
- * @param {Function} [obj.validator] validator function. If the validator function returns `undefined` or a truthy value, validation succeeds. If it returns falsy (except `undefined`) or throws an error, validation fails.
+ * @param {Function} [obj.validator] validator function. If the validator function returns `undefined` or a truthy value, validation succeeds. If it returns [falsy](https://masteringjs.io/tutorials/fundamentals/falsy) (except `undefined`) or throws an error, validation fails.
  * @param {String|Function} [obj.message] optional error message. If function, should return the error message as a string
  * @param {Boolean} [obj.propsParameter=false] If true, Mongoose will pass the validator properties object (with the `validator` function, `message`, etc.) as the 2nd arg to the validator function. This is disabled by default because many validators [rely on positional args](https://github.com/chriso/validator.js#validators), so turning this on may cause unpredictable behavior in external validators.
  * @param {String|Function} [errorMsg] optional error message. If function, should return the error message as a string

From fcbed7bbe1a90be845c74f1ed0eef63d6b599a93 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 4 Nov 2019 14:02:30 -0500
Subject: [PATCH 0131/2348] chore: release 5.7.8

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 5b58e4216a8..62f027c0bae 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.7.8 / 2019-11-04
+==================
+ * fix(document): allow manually populating path within document array #8273
+ * fix(populate): update top-level `populated()` when updating document array with populated subpaths #8265
+ * fix(cursor): throw error when using aggregation cursor as async iterator #8280
+ * fix(schema): retain `_id: false` in schema after nesting in another schema #8274
+ * fix(document): make Document class an event emitter to support defining documents without models in node #8272
+ * docs: document return types for `.discriminator()` #8287
+ * docs(connection): add note about exporting schemas, not models, in multi connection paradigm #8275
+ * docs: clarify that transforms defined in `toObject()` options are applied to subdocs #8260
+
 5.7.7 / 2019-10-24
 ==================
  * fix(populate): make populate virtual consistently an empty array if local field is only empty arrays #8230
diff --git a/package.json b/package.json
index c7a3e78cfc4..3ae9600a504 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.8-pre",
+  "version": "5.7.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 8c79cdde23b27b3d91326cdee92b775038980ca9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 4 Nov 2019 14:15:23 -0500
Subject: [PATCH 0132/2348] chore: clean up unnecessary eslint rules that are
 confusing docs parsing

---
 lib/schema/array.js         | 4 ++--
 lib/schema/documentarray.js | 2 +-
 package.json                | 5 +----
 3 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 718961df23d..09547385374 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -196,8 +196,8 @@ SchemaArray.prototype.checkRequired = function checkRequired(value, doc) {
  */
 
 SchemaArray.prototype.enum = function() {
-  let arr = this; /* eslint consistent-this: 0 */
-  while (true) { /* eslint no-constant-condition: 0 */
+  let arr = this;
+  while (true) {
     const instance = get(arr, 'caster.instance');
     if (instance === 'Array') {
       arr = arr.caster;
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 4f8cbb026d3..9d95f2727a4 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -56,7 +56,7 @@ function DocumentArrayPath(key, schema, options, schemaOptions) {
     });
   }
 
-  const parentSchemaType = this; /* eslint consistent-this: 0 */
+  const parentSchemaType = this;
   this.$embeddedSchemaType = new SchemaType(key + '.$', {
     required: get(this, 'schemaOptions.required', false)
   });
diff --git a/package.json b/package.json
index 3ae9600a504..f66a3a006c4 100644
--- a/package.json
+++ b/package.json
@@ -102,10 +102,6 @@
     },
     "rules": {
       "comma-style": "error",
-      "consistent-this": [
-        "error",
-        "_this"
-      ],
       "indent": [
         "error",
         2,
@@ -118,6 +114,7 @@
       "no-buffer-constructor": "warn",
       "no-console": "off",
       "no-multi-spaces": "error",
+      "no-constant-condition": "off",
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",
       "quotes": [

From 0bdc11e923132cc31945db7f12ba7eb4c5b270ad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Nov 2019 11:34:53 -0500
Subject: [PATCH 0133/2348] chore: add crosswordsolver as a sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 441589a5b25..f3cdb9c2537 100644
--- a/index.pug
+++ b/index.pug
@@ -259,6 +259,9 @@ html(lang='en')
               <a href="https://www.bonus.ca">
                 <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo.png" style="height: 100px">
               </a>
+              <a href="https://www.crosswordsolver.com/">
+                <img class="sponsor" src="https://images.opencollective.com/crosswordsolver/d4481d6/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 4f2fe4f8ac85d6a13b776b9bacbd1ee447620c5c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Nov 2019 14:35:10 -0500
Subject: [PATCH 0134/2348] chore: add new opencollective sponsors

---
 index.pug | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/index.pug b/index.pug
index f3cdb9c2537..fd37d144ace 100644
--- a/index.pug
+++ b/index.pug
@@ -184,6 +184,15 @@ html(lang='en')
               <a href="https://www.embedgooglemap.net/blog/best-wordpress-themes/">
                 <img class="sponsor" title=" Best WordPress Themes " src="https://www.embedgooglemap.net/ultimate-wp-logo.png" style="height:100px">
               </a>
+              <a href="https://loanscouter.com/">
+                <img class="sponsor" src="https://images.opencollective.com/lead-supply/7400b71/logo.png" style="height: 100px">
+              </a>
+              <a href="https://superkredit.net/">
+                <img class="sponsor" src="https://images.opencollective.com/superkredit/6eb441d/logo.png" style="height: 100px">
+              </a>
+              <a href="https://fair-laan.se/">
+                <img class="sponsor" src="https://images.opencollective.com/fair-laan-se/939304b/logo.png" style="height: 100px">
+              </a>
               <a href="https://craftresumes.com/professional-resume-writer/">
                 <img class="sponsor" alt="Professional resume writer" src="https://s3.amazonaws.com/codebarbarian-images/craftresumes.png">
               </a>
@@ -253,9 +262,6 @@ html(lang='en')
               <a href="https://vpnblackfriday.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
               </a>
-              <a href="https://loanscouter.com/">
-                <img class="sponsor" src="https://images.opencollective.com/lead-supply/7400b71/logo.png" style="height: 100px">
-              </a>
               <a href="https://www.bonus.ca">
                 <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo.png" style="height: 100px">
               </a>

From 328f94e115ca95b49eb26bb0530a150f062abd43 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Nov 2019 14:38:27 -0500
Subject: [PATCH 0135/2348] chore: remove opencollective sponsor

---
 index.pug | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/index.pug b/index.pug
index fd37d144ace..cb808d92e67 100644
--- a/index.pug
+++ b/index.pug
@@ -235,9 +235,6 @@ html(lang='en')
               <a href="https://proxybaylist.org/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy-bay/e176fe4/avatar.png" style="height: 100px">
               </a>
-              <a href="https://www.ehic-cards.org.uk/">
-                <img class="sponsor" src="https://images.opencollective.com/limit-limited/c61b047/logo.png" style="height: 100px">
-              </a>
               <a href="https://www.dcslsoftware.com/">
                 <img class="sponsor" src="https://images.opencollective.com/dcsl-software/a662911/logo.png" style="height: 100px">
               </a>

From 081f2ec95e1c1868f05d80b6f200c7c4e43529cb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Nov 2019 19:42:24 -0500
Subject: [PATCH 0136/2348] test(schema): repro #8292

---
 test/schema.test.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 23ecf032ba4..62a813408bf 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2144,4 +2144,14 @@ describe('schema', function() {
       filter(key => ['constructor', 'cast', 'castForQuery', 'checkRequired'].indexOf(key) === -1);
     assert.deepEqual(keys.sort(), functions.sort());
   });
+
+  it('supports passing schema options to `Schema#path()` (gh-8292)', function() {
+    const schema = Schema({ title: String });
+    const path = schema.path('title');
+
+    const newSchema = Schema({});
+    newSchema.add({ title: path.options });
+
+    assert.equal(newSchema.path('title').options.type, String);
+  });
 });

From d02ebd23c0ff337c2987963b62e9c911a7c9a693 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Nov 2019 20:11:07 -0500
Subject: [PATCH 0137/2348] fix(schema): support setting schema path to an
 instance of SchemaTypeOptions

Fix #8292
---
 lib/options/SchemaArrayOptions.js    | 7 +------
 lib/options/SchemaBufferOptions.js   | 7 +------
 lib/options/SchemaDateOptions.js     | 7 +------
 lib/options/SchemaNumberOptions.js   | 7 +------
 lib/options/SchemaObjectIdOptions.js | 7 +------
 lib/options/SchemaStringOptions.js   | 7 +------
 lib/options/SchemaTypeOptions.js     | 7 +------
 lib/options/propertyOptions.js       | 8 ++++++++
 lib/schema.js                        | 5 +++--
 9 files changed, 18 insertions(+), 44 deletions(-)
 create mode 100644 lib/options/propertyOptions.js

diff --git a/lib/options/SchemaArrayOptions.js b/lib/options/SchemaArrayOptions.js
index 74c39f69098..ddd0b37a935 100644
--- a/lib/options/SchemaArrayOptions.js
+++ b/lib/options/SchemaArrayOptions.js
@@ -17,12 +17,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
 
 class SchemaArrayOptions extends SchemaTypeOptions {}
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * If this is an array of strings, an array of allowed values for this path.
diff --git a/lib/options/SchemaBufferOptions.js b/lib/options/SchemaBufferOptions.js
index 96577b989e2..258130dfee8 100644
--- a/lib/options/SchemaBufferOptions.js
+++ b/lib/options/SchemaBufferOptions.js
@@ -17,12 +17,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
 
 class SchemaBufferOptions extends SchemaTypeOptions {}
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * Set the default subtype for this buffer.
diff --git a/lib/options/SchemaDateOptions.js b/lib/options/SchemaDateOptions.js
index 5a88a77a8c2..09bf27f6adf 100644
--- a/lib/options/SchemaDateOptions.js
+++ b/lib/options/SchemaDateOptions.js
@@ -17,12 +17,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
 
 class SchemaDateOptions extends SchemaTypeOptions {}
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * If set, Mongoose adds a validator that checks that this path is after the
diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index 6260ea74a10..e14e1cc9171 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -17,12 +17,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
 
 class SchemaNumberOptions extends SchemaTypeOptions {}
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * If set, Mongoose adds a validator that checks that this path is at least the
diff --git a/lib/options/SchemaObjectIdOptions.js b/lib/options/SchemaObjectIdOptions.js
index 440701cea31..cf887d0b7fe 100644
--- a/lib/options/SchemaObjectIdOptions.js
+++ b/lib/options/SchemaObjectIdOptions.js
@@ -17,12 +17,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
 
 class SchemaObjectIdOptions extends SchemaTypeOptions {}
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * If truthy, uses Mongoose's default built-in ObjectId path.
diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index 8c6bb0ac067..765499355d6 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -17,12 +17,7 @@ const SchemaTypeOptions = require('./SchemaTypeOptions');
 
 class SchemaStringOptions extends SchemaTypeOptions {}
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * Array of allowed values for this path
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index eef74f6829f..0a7236db8fe 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -23,12 +23,7 @@ class SchemaTypeOptions {
   }
 }
 
-const opts = {
-  enumerable: true,
-  configurable: true,
-  writable: true,
-  value: null
-};
+const opts = require('./propertyOptions');
 
 /**
  * The type to cast this path to.
diff --git a/lib/options/propertyOptions.js b/lib/options/propertyOptions.js
new file mode 100644
index 00000000000..b7488a37ee9
--- /dev/null
+++ b/lib/options/propertyOptions.js
@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = Object.freeze({
+  enumerable: true,
+  configurable: true,
+  writable: true,
+  value: void 0
+});
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index 00acac49b2f..73318da0859 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -7,6 +7,7 @@
 const EventEmitter = require('events').EventEmitter;
 const Kareem = require('kareem');
 const SchemaType = require('./schematype');
+const SchemaTypeOptions = require('./options/SchemaTypeOptions');
 const VirtualType = require('./virtualtype');
 const applyTimestampsToChildren = require('./helpers/update/applyTimestampsToChildren');
 const applyTimestampsToUpdate = require('./helpers/update/applyTimestampsToUpdate');
@@ -426,7 +427,7 @@ Schema.prototype.add = function add(obj, prefix) {
         '`, got value "' + obj[key][0] + '"');
     }
 
-    if (utils.isPOJO(obj[key]) &&
+    if ((utils.isPOJO(obj[key]) || obj[key] instanceof SchemaTypeOptions) &&
         (!obj[key][this.options.typeKey] || (this.options.typeKey === 'type' && obj[key].type.type))) {
       if (Object.keys(obj[key]).length) {
         // nested object { last: { name: String }}
@@ -795,7 +796,7 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
   // copy of SchemaTypes re: gh-7158 gh-6933
   const MongooseTypes = this.base != null ? this.base.Schema.Types : Schema.Types;
 
-  if (obj.constructor) {
+  if (!utils.isPOJO(obj) && !(obj instanceof SchemaTypeOptions)) {
     const constructorName = utils.getFunctionName(obj.constructor);
     if (constructorName !== 'Object') {
       const oldObj = obj;

From f0aeddc44a6f18554268b6054eafbfa8b1e4f59d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Nov 2019 12:00:46 -0500
Subject: [PATCH 0138/2348] test(populate): repro #8293

---
 test/model.populate.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 0ca10658838..5d8750d5c66 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8770,5 +8770,32 @@ describe('model: populate:', function() {
         assert.equal(pop.length, 1);
       });
     });
+
+    it('retainNullValues stores `null` in array if foreign doc not found (gh-8293)', function() {
+      const schema = Schema({ troops: [{ type: Number, ref: 'gh8293_Card' }] });
+      const Team = db.model('gh8293_Team', schema);
+
+      const Card = db.model('gh8293_Card', Schema({
+        _id: { type: Number },
+        name: { type: String, unique: true },
+        entityType: { type: String }
+      }));
+
+      return co(function*() {
+        yield Card.create([
+          { _id: 2, name: 'Card 2' },
+          { _id: 3, name: 'Card 3' },
+          { _id: 4, name: 'Card 4' }
+        ]);
+        yield Team.create({ troops: [1, 2, 3, 4] });
+
+        const doc = yield Team.findOne().populate({
+          path: 'troops',
+          options: { retainNullValues: true }
+        });
+        assert.equal(doc.troops.length, 4);
+        assert.equal(doc.troops[0], null);
+      });
+    });
   });
 });

From 9b0e96d1d3e129a8f80dfd1668766e9666d49023 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Nov 2019 12:18:36 -0500
Subject: [PATCH 0139/2348] fix(populate): make `retainNullValues` set array
 element to `null` if foreign doc with that id was not found

Fix #8293
---
 lib/helpers/populate/assignRawDocsToIdStructure.js | 6 +++++-
 test/model.populate.test.js                        | 3 +++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignRawDocsToIdStructure.js b/lib/helpers/populate/assignRawDocsToIdStructure.js
index bb3d988a68e..b84f7131ca2 100644
--- a/lib/helpers/populate/assignRawDocsToIdStructure.js
+++ b/lib/helpers/populate/assignRawDocsToIdStructure.js
@@ -1,5 +1,7 @@
 'use strict';
 
+const modelSymbol = require('../symbols').modelSymbol;
+
 module.exports = assignRawDocsToIdStructure;
 
 /*!
@@ -63,8 +65,10 @@ function assignRawDocsToIdStructure(rawIds, resultDocs, resultOrder, options, re
         } else {
           newOrder.push(doc);
         }
+      } else if (id != null && id[modelSymbol] != null) {
+        newOrder.push(id);
       } else {
-        newOrder.push(nullIfNotFound ? null : id);
+        newOrder.push(options.retainNullValues || nullIfNotFound ? null : id);
       }
     } else {
       // apply findOne behavior - if document in results, assign, else assign null
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5d8750d5c66..eaf72afdbf7 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8795,6 +8795,9 @@ describe('model: populate:', function() {
         });
         assert.equal(doc.troops.length, 4);
         assert.equal(doc.troops[0], null);
+        assert.equal(doc.troops[1].name, 'Card 2');
+        assert.equal(doc.troops[2].name, 'Card 3');
+        assert.equal(doc.troops[3].name, 'Card 4');
       });
     });
   });

From 1c4d9946c0aba599a476326339c8e834de815673 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Nov 2019 12:19:39 -0500
Subject: [PATCH 0140/2348] chore: now working on 5.7.9

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index f66a3a006c4..5d12faf4f01 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.8",
+  "version": "5.7.9-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From de3eee5122f462eff41c86fe39dec197d655afed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Nov 2019 13:18:27 -0500
Subject: [PATCH 0141/2348] docs: add link to custom casting guide

---
 docs/guides.pug | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/docs/guides.pug b/docs/guides.pug
index 0e94d655c53..3118e771281 100644
--- a/docs/guides.pug
+++ b/docs/guides.pug
@@ -41,9 +41,14 @@ block content
     * [Getters and Setters](/docs/tutorials/getters-setters.html)
     * [Virtuals](/docs/tutorials/virtuals.html)
 
-    ### Integrations
+    ### Advanced Topics
 
+    * [Working with Dates](/docs/tutorials/dates.html)
+    * [Custom Casting For Built-in Types](/docs/tutorials/custom-casting.html)
     * [Custom SchemaTypes](/docs/customschematypes.html)
+
+    ### Integrations
+
     * [Promises](/docs/promises.html)
     * [AWS Lambda](/docs/lambda.html)
     * [Browser Library](/docs/browser.html)
@@ -51,7 +56,6 @@ block content
     * [Transactions](/docs/transactions.html)
     * [MongoDB Driver Deprecation Warnings](/docs/deprecations.html)
     * [Testing with Jest](/docs/jest.html)
-    * [Working with Dates](/docs/tutorials/dates.html)
 
     ### Migration Guides
 

From 6c1d46af3be39aff01fab11834c9ae28277ad9c4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 7 Nov 2019 19:47:51 -0500
Subject: [PATCH 0142/2348] fix(model): allow objects with `toBSON()` to make
 it to `save()`

Fix #8299
---
 lib/model.js          |  6 +++++-
 lib/utils.js          |  7 +++++++
 test/document.test.js | 17 +++++++++++++++++
 test/utils.test.js    | 14 ++++++++++++++
 4 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index b95f4ad3bf2..6f10c5f9ee1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -52,6 +52,10 @@ const modelDbSymbol = Symbol('mongoose#Model#db');
 const modelSymbol = require('./helpers/symbols').modelSymbol;
 const subclassedSymbol = Symbol('mongoose#Model#subclassed');
 
+const saveToObjectOptions = Object.assign({}, internalToObjectOptions, {
+  bson: true
+});
+
 /**
  * A Model is a class that's your primary tool for interacting with MongoDB.
  * An instance of a Model is called a [Document](./api.html#Document).
@@ -244,7 +248,7 @@ Model.prototype.$__handleSave = function(options, callback) {
 
   if (this.isNew) {
     // send entire doc
-    const obj = this.toObject(internalToObjectOptions);
+    const obj = this.toObject(saveToObjectOptions);
 
     if ((obj || {})._id === void 0) {
       // documents must have an _id else mongoose won't know
diff --git a/lib/utils.js b/lib/utils.js
index 846b68ee0ac..e423f6935ef 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -232,6 +232,13 @@ exports.clone = function clone(obj, options, isArrayChild) {
     return obj.clone();
   }
 
+  // If we're cloning this object to go into a MongoDB command,
+  // and there's a `toBSON()` function, assume this object will be
+  // stored as a primitive in MongoDB and doesn't need to be cloned.
+  if (options && options.bson && typeof obj.toBSON === 'function') {
+    return obj;
+  }
+
   if (obj.valueOf != null) {
     return obj.valueOf();
   }
diff --git a/test/document.test.js b/test/document.test.js
index 1643cab63ee..f8a6bf1c3e6 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8141,4 +8141,21 @@ describe('document', function() {
       assert.equal(fromDb.activity.description, 'after');
     });
   });
+
+  it('passing an object with toBSON() into `save()` (gh-8299)', function() {
+    const ActivitySchema = Schema({ description: String });
+    const RequestSchema = Schema({ activity: ActivitySchema });
+    const Request = db.model('gh8299', RequestSchema);
+
+    return co(function*() {
+      const doc = yield Request.create({
+        activity: { description: 'before' }
+      });
+      doc.activity.set({ description: 'after' });
+      yield doc.save();
+
+      const fromDb = yield Request.findOne().lean();
+      assert.equal(fromDb.activity.description, 'after');
+    });
+  });
 });
diff --git a/test/utils.test.js b/test/utils.test.js
index 9431e463ea2..9d2e92f1048 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -340,5 +340,19 @@ describe('utils', function() {
 
       done();
     });
+
+    it('skips cloning types that have `toBSON()` if `bson` is set (gh-8299)', function() {
+      const o = {
+        toBSON() {
+          return 'toBSON';
+        },
+        valueOf() {
+          return 'valueOf()';
+        }
+      };
+
+      const out = utils.clone(o, { bson: true });
+      assert.deepEqual(out, o);
+    });
   });
 });

From d4648ee8b3f430e23ad687f836e55678273a7fbf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Nov 2019 12:02:24 -0500
Subject: [PATCH 0143/2348] test(document): repro #8295

---
 test/document.test.js | 32 ++++++++++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index f8a6bf1c3e6..73d77238d4c 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -868,19 +868,19 @@ describe('document', function() {
       userSchema.virtual('hello').get(function() {
         return 'Hello, ' + this.name;
       });
-      const User = db.model('User', userSchema);
+      const User = db.model('gh1376_User', userSchema);
 
       const groupSchema = new Schema({
         name: String,
-        _users: [{type: Schema.ObjectId, ref: 'User'}]
+        _users: [{type: Schema.ObjectId, ref: 'gh1376_User'}]
       });
 
-      const Group = db.model('Group', groupSchema);
+      const Group = db.model('gh1376_Group', groupSchema);
 
       User.create({name: 'Alice'}, {name: 'Bob'}, function(err, alice, bob) {
         assert.ifError(err);
 
-        new Group({name: 'mongoose', _users: [alice, bob]}).save(function(err, group) {
+        Group.create({name: 'mongoose', _users: [alice, bob]}, function(err, group) {
           Group.findById(group).populate('_users').exec(function(err, group) {
             assert.ifError(err);
             assert.ok(group.toJSON()._users[0].hello);
@@ -8158,4 +8158,28 @@ describe('document', function() {
       assert.equal(fromDb.activity.description, 'after');
     });
   });
+
+  it('handles getter setting virtual on manually populated doc when calling toJSON (gh-8295)', function() {
+    const childSchema = Schema({}, { toJSON: { getters: true } });
+    childSchema.virtual('field').
+      get(function() { return this._field; }).
+      set(function(v) { return this._field = v; });
+    const Child = db.model('gh8295_Child', childSchema);
+
+    const parentSchema = Schema({
+      child: { type: mongoose.ObjectId, ref: 'gh8295_Child', get }
+    }, { toJSON: { getters: true } });
+    const Parent = db.model('gh8295_Parent', parentSchema);
+
+    function get(child) {
+      child.field = true;
+      return child;
+    }
+
+    let p = new Parent({ child: new Child({}) });
+    assert.strictEqual(p.toJSON().child.field, true);
+
+    p = new Parent({ child: new Child({}) });
+    assert.strictEqual(p.child.toJSON().field, true);
+  });
 });

From 03ef4d8825baceeef1e9ee9a7744707829d0c05c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Nov 2019 12:02:57 -0500
Subject: [PATCH 0144/2348] fix(document): support getter setting virtual on
 manually populated doc when calling toJSON()

Fix #8295
---
 lib/document.js | 27 ++++++++++++++++-----------
 lib/utils.js    |  5 +++++
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 6213508261d..465d405c700 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2836,6 +2836,13 @@ Document.prototype.$toObject = function(options, json) {
     minimize: _minimize
   });
 
+  if (utils.hasUserDefinedProperty(options, 'getters')) {
+    cloneOptions.getters = options.getters;
+  }
+  if (utils.hasUserDefinedProperty(options, 'virtuals')) {
+    cloneOptions.virtuals = options.virtuals;
+  }
+
   const depopulate = options.depopulate ||
     get(options, '_parentOptions.depopulate', false);
   // _isNested will only be true if this is not the top level document, we
@@ -2852,6 +2859,10 @@ Document.prototype.$toObject = function(options, json) {
   options.minimize = _minimize;
 
   cloneOptions._parentOptions = options;
+  cloneOptions._skipSingleNestedGetters = true;
+
+  const gettersOptions = Object.assign({}, cloneOptions);
+  gettersOptions._skipSingleNestedGetters = false;
 
   // remember the root transform function
   // to save it from being overwritten by sub-transform functions
@@ -2860,16 +2871,15 @@ Document.prototype.$toObject = function(options, json) {
   let ret = clone(this._doc, cloneOptions) || {};
 
   if (options.getters) {
-    applyGetters(this, ret, cloneOptions);
-    // applyGetters for paths will add nested empty objects;
-    // if minimize is set, we need to remove them.
+    applyGetters(this, ret, gettersOptions);
+
     if (options.minimize) {
       ret = minimize(ret) || {};
     }
   }
 
-  if (options.virtuals || options.getters && options.virtuals !== false) {
-    applyVirtuals(this, ret, cloneOptions, options);
+  if (options.virtuals || (options.getters && options.virtuals !== false)) {
+    applyVirtuals(this, ret, gettersOptions, options);
   }
 
   if (options.versionKey === false && this.schema.options.versionKey) {
@@ -3180,12 +3190,7 @@ function applyGetters(self, json, options) {
       v = cur[part];
       if (ii === last) {
         const val = self.get(path);
-        // Ignore single nested docs: getters will run because of `clone()`
-        // before `applyGetters()` in `$toObject()`. Quirk because single
-        // nested subdocs are hydrated docs in `_doc` as opposed to POJOs.
-        if (val != null && val.$__ == null) {
-          branch[part] = clone(val, options);
-        }
+        branch[part] = clone(val, options);
       } else if (v == null) {
         if (part in cur) {
           branch[part] = v;
diff --git a/lib/utils.js b/lib/utils.js
index e423f6935ef..8b35ebbaf40 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -193,6 +193,11 @@ exports.clone = function clone(obj, options, isArrayChild) {
   }
 
   if (isMongooseObject(obj)) {
+    // Single nested subdocs should apply getters later in `applyGetters()`
+    // when calling `toObject()`. See gh-7442, gh-8295
+    if (options && options._skipSingleNestedGetters && obj.$isSingleNested) {
+      options = Object.assign({}, options, { getters: false });
+    }
     if (options && options.json && typeof obj.toJSON === 'function') {
       return obj.toJSON(options);
     }

From 97d6900156d97e0447bc9c273752fff211398bf9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Nov 2019 12:05:53 -0500
Subject: [PATCH 0145/2348] test: fix tests for node 4.x and 5.x

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 73d77238d4c..a4204870ec8 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8167,7 +8167,7 @@ describe('document', function() {
     const Child = db.model('gh8295_Child', childSchema);
 
     const parentSchema = Schema({
-      child: { type: mongoose.ObjectId, ref: 'gh8295_Child', get }
+      child: { type: mongoose.ObjectId, ref: 'gh8295_Child', get: get }
     }, { toJSON: { getters: true } });
     const Parent = db.model('gh8295_Parent', parentSchema);
 

From 537217e663e3e1ded81348413c92c9107424b471 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Nov 2019 15:08:13 -0500
Subject: [PATCH 0146/2348] chore: release 5.7.9

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 62f027c0bae..6db11f0fcfb 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.7.9 / 2019-11-08
+==================
+ * fix(schema): support setting schema path to an instance of SchemaTypeOptions to fix integration with mongoose-i18n-localize #8297 #8292
+ * fix(populate): make `retainNullValues` set array element to `null` if foreign doc with that id was not found #8293
+ * fix(document): support getter setting virtual on manually populated doc when calling toJSON() #8295
+ * fix(model): allow objects with `toBSON()` to make it to `save()` #8299
+
 5.7.8 / 2019-11-04
 ==================
  * fix(document): allow manually populating path within document array #8273
diff --git a/package.json b/package.json
index 5d12faf4f01..0e59ddfd134 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.9-pre",
+  "version": "5.7.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 81c61f61387d02b974c2e48e8de6f498a9a1e120 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 12:20:46 -0500
Subject: [PATCH 0147/2348] chore: add opencollective sponsors

---
 index.pug | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/index.pug b/index.pug
index cb808d92e67..c4f4d0215f2 100644
--- a/index.pug
+++ b/index.pug
@@ -256,8 +256,14 @@ html(lang='en')
               <a href="https://www.casinotopp.net">
                 <img class="sponsor" src="https://images.opencollective.com/casino-topp/1dd399a/logo.png" style="height: 100px">
               </a>
-              <a href="https://vpnblackfriday.com/">
-                <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
+              <a href="https://www.bonus.net.nz/free-spins">
+                <img class="sponsor" src="https://images.opencollective.com/bonusfinder-new-zealand/a5becb5/logo.png" style="height: 100px">
+              </a>
+              <a href="https://www.bonusfinder.com/casino">
+                <img class="sponsor" src="https://images.opencollective.com/bonusfinder-com-us/8a47a19/logo.png" style="height: 100px">
+              </a>
+              <a href="https://www.bonus.com.de/freispiele">
+                <img class="sponsor" src="https://images.opencollective.com/bonusfinder-deutschland/646169e/logo.png" style="height: 100px">
               </a>
               <a href="https://www.bonus.ca">
                 <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo.png" style="height: 100px">
@@ -265,6 +271,9 @@ html(lang='en')
               <a href="https://www.crosswordsolver.com/">
                 <img class="sponsor" src="https://images.opencollective.com/crosswordsolver/d4481d6/logo.png" style="height: 100px">
               </a>
+              <a href="https://vpnblackfriday.com/">
+                <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From e6859bc3abd65e2ce623363544a9fa878f9e41a5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 12:58:09 -0500
Subject: [PATCH 0148/2348] test: clean up test for timestamps with
 insertMany() re: #8304

---
 test/model.test.js | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index a0bf8dc8960..bfe47729154 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4756,24 +4756,26 @@ describe('Model', function() {
       });
     });
 
-    it('insertMany() with timestamps (gh-723)', function(done) {
-      const schema = new Schema({
-        name: String
-      });
+    it('insertMany() with timestamps (gh-723)', function() {
+      const schema = new Schema({ name: String }, { timestamps: true });
       const Movie = db.model('gh723_0', schema);
+      const start = Date.now();
 
       const arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
-      Movie.insertMany(arr, function(error, docs) {
-        assert.ifError(error);
-        assert.equal(docs.length, 2);
-        assert.ok(!docs[0].isNew);
-        assert.ok(!docs[1].isNew);
-        Movie.find({}, function(error, docs) {
-          assert.ifError(error);
+      return Movie.insertMany(arr).
+        then(docs => {
           assert.equal(docs.length, 2);
-          done();
+          assert.ok(!docs[0].isNew);
+          assert.ok(!docs[1].isNew);
+          assert.ok(docs[0].createdAt.valueOf() >= start);
+          assert.ok(docs[1].createdAt.valueOf() >= start);
+        }).
+        then(() => Movie.find()).
+        then(docs => {
+          assert.equal(docs.length, 2);
+          assert.ok(docs[0].createdAt.valueOf() >= start);
+          assert.ok(docs[1].createdAt.valueOf() >= start);
         });
-      });
     });
 
     it('returns empty array if no documents (gh-8130)', function() {

From 6067dcd1cf416baa91bfd266df0ec63adcbc5e25 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 13:15:56 -0500
Subject: [PATCH 0149/2348] chore: alternative crosswordsolver logo re: #8301

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index c4f4d0215f2..9a8aae1354f 100644
--- a/index.pug
+++ b/index.pug
@@ -269,7 +269,7 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo.png" style="height: 100px">
               </a>
               <a href="https://www.crosswordsolver.com/">
-                <img class="sponsor" src="https://images.opencollective.com/crosswordsolver/d4481d6/logo.png" style="height: 100px">
+                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/crosswordsolver.png" style="height: 80px">
               </a>
               <a href="https://vpnblackfriday.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">

From bea0b6d45c98b4c8c23a39012fb961303a462210 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 13:51:19 -0500
Subject: [PATCH 0150/2348] chore: ensure all node tests do
 `require('./common')` first so they can work independently

Fix #8308
---
 test/aggregate.test.js                    | 3 ++-
 test/cast.test.js                         | 2 ++
 test/collection.capped.test.js            | 3 ++-
 test/collection.test.js                   | 3 ++-
 test/colors.js                            | 3 ++-
 test/connection.test.js                   | 3 ++-
 test/document.isselected.test.js          | 8 +++++---
 test/document.modified.test.js            | 3 ++-
 test/document.populate.test.js            | 3 ++-
 test/document.strict.test.js              | 3 ++-
 test/document.test.js                     | 3 ++-
 test/document.unit.test.js                | 3 ++-
 test/errors.validation.test.js            | 3 ++-
 test/geojson.test.js                      | 3 ++-
 test/gh-1408.test.js                      | 3 ++-
 test/index.test.js                        | 3 ++-
 test/model.aggregate.test.js              | 3 ++-
 test/model.create.test.js                 | 4 +++-
 test/model.discriminator.querying.test.js | 1 +
 test/model.discriminator.test.js          | 3 ++-
 test/model.field.selection.test.js        | 3 ++-
 test/model.findOneAndDelete.test.js       | 3 ++-
 test/model.findOneAndRemove.test.js       | 3 ++-
 test/model.findOneAndReplace.test.js      | 3 ++-
 test/model.findOneAndUpdate.test.js       | 3 ++-
 test/model.geosearch.test.js              | 3 ++-
 test/model.hydrate.test.js                | 3 ++-
 test/model.indexes.test.js                | 3 ++-
 test/model.mapreduce.test.js              | 3 ++-
 test/model.middleware.test.js             | 3 ++-
 test/model.populate.divergent.test.js     | 3 ++-
 test/model.populate.setting.test.js       | 3 ++-
 test/model.populate.test.js               | 3 ++-
 test/model.query.casting.test.js          | 3 ++-
 test/model.querying.test.js               | 3 ++-
 test/model.test.js                        | 3 ++-
 test/model.translateAliases.test.js       | 3 ++-
 test/model.update.test.js                 | 3 ++-
 test/object.create.null.test.js           | 3 ++-
 test/plugin.idGetter.test.js              | 3 ++-
 test/query.cursor.test.js                 | 3 ++-
 test/query.middleware.test.js             | 1 +
 test/query.test.js                        | 1 +
 test/query.toconstructor.test.js          | 3 ++-
 test/schema.alias.test.js                 | 3 ++-
 test/schema.boolean.test.js               | 3 ++-
 test/schema.date.test.js                  | 3 ++-
 test/schema.documentarray.test.js         | 3 ++-
 test/schema.mixed.test.js                 | 3 ++-
 test/schema.onthefly.test.js              | 3 ++-
 test/schema.select.test.js                | 3 ++-
 test/schema.test.js                       | 1 +
 test/schema.timestamps.test.js            | 3 ++-
 test/schema.type.test.js                  | 1 +
 test/schema.validation.test.js            | 3 ++-
 test/schematype.cast.test.js              | 2 ++
 test/services.query.test.js               | 2 ++
 test/shard.test.js                        | 3 ++-
 test/timestamps.test.js                   | 3 ++-
 test/types.array.test.js                  | 3 ++-
 test/types.buffer.test.js                 | 3 ++-
 test/types.decimal128.test.js             | 3 ++-
 test/types.document.test.js               | 3 ++-
 test/types.documentarray.test.js          | 3 ++-
 test/types.embeddeddocument.test.js       | 3 ++-
 test/types.map.test.js                    | 3 ++-
 test/types.number.test.js                 | 3 ++-
 test/types.subdocument.test.js            | 3 ++-
 test/updateValidators.unit.test.js        | 2 ++
 test/utils.test.js                        | 3 ++-
 test/versioning.test.js                   | 3 ++-
 71 files changed, 141 insertions(+), 64 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index c20d7cd374c..3c417deb53b 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -4,9 +4,10 @@
  * Module dependencies
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 
 const Aggregate = require('../lib/aggregate');
 
diff --git a/test/cast.test.js b/test/cast.test.js
index 19cabd6ebfa..7716f0b1120 100644
--- a/test/cast.test.js
+++ b/test/cast.test.js
@@ -4,6 +4,8 @@
 
 'use strict';
 
+require('./common');
+
 const Schema = require('../lib/schema');
 const assert = require('assert');
 const cast = require('../lib/cast');
diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index 06b48fc66a9..1a2ad1d7219 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -4,9 +4,10 @@
 
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/collection.test.js b/test/collection.test.js
index a6f58d0f12b..a7d7ec2c27a 100644
--- a/test/collection.test.js
+++ b/test/collection.test.js
@@ -1,8 +1,9 @@
 'use strict';
 
+const start = require('./common');
+
 const Collection = require('../lib/collection');
 const assert = require('assert');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 
diff --git a/test/colors.js b/test/colors.js
index 498e103cdbf..224beb24aa7 100644
--- a/test/colors.js
+++ b/test/colors.js
@@ -4,10 +4,11 @@
 
 'use strict';
 
+const start = require('./common');
+
 const DocumentArray = require('../lib/types/documentarray');
 const EmbeddedDocument = require('../lib/types/embedded');
 const assert = require('assert');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/connection.test.js b/test/connection.test.js
index 4d97b7caf84..6a4a61a4697 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -4,12 +4,13 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const Promise = require('bluebird');
 const Q = require('q');
 const assert = require('assert');
 const co = require('co');
 const server = require('./common').server;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/document.isselected.test.js b/test/document.isselected.test.js
index 47f4348d55c..4cea9e4b10f 100644
--- a/test/document.isselected.test.js
+++ b/test/document.isselected.test.js
@@ -5,12 +5,14 @@
 'use strict';
 
 const start = require('./common');
-const mongoose = start.mongoose;
-const assert = require('assert');
+
+const Document = require('../lib/document');
 const EventEmitter = require('events').EventEmitter;
+const assert = require('assert');
+
+const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 const ObjectId = Schema.ObjectId;
-const Document = require('../lib/document');
 const DocumentObjectId = mongoose.Types.ObjectId;
 
 /**
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 231d61f27ea..590c42ad13f 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -4,9 +4,10 @@
 
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index 4e1ba3f098e..9ab17579bd5 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -5,10 +5,11 @@
 
 'use strict';
 
+const start = require('./common');
+
 const Document = require('../lib/document');
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 const utils = require('../lib/utils');
 
 const mongoose = start.mongoose;
diff --git a/test/document.strict.test.js b/test/document.strict.test.js
index 562544e8e6c..15a6b530c31 100644
--- a/test/document.strict.test.js
+++ b/test/document.strict.test.js
@@ -4,10 +4,11 @@
 
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/document.test.js b/test/document.test.js
index a4204870ec8..7b466a47156 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -4,6 +4,8 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const Document = require('../lib/document');
 const EventEmitter = require('events').EventEmitter;
 const EmbeddedDocument = require('../lib/types/embedded');
@@ -11,7 +13,6 @@ const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 const utils = require('../lib/utils');
 const validator = require('validator');
 const Buffer = require('safe-buffer').Buffer;
diff --git a/test/document.unit.test.js b/test/document.unit.test.js
index 03cb3af7f92..86923f2c0b5 100644
--- a/test/document.unit.test.js
+++ b/test/document.unit.test.js
@@ -4,8 +4,9 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
+
+const assert = require('assert');
 const storeShard = require('../lib/plugins/sharding').storeShard;
 
 const mongoose = start.mongoose;
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 8a1aecd4226..554847152e6 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -5,9 +5,10 @@
 
 'use strict';
 
+const start = require('./common');
+
 const ValidationError = require('../lib/error/validation');
 const assert = require('assert');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/geojson.test.js b/test/geojson.test.js
index e1d33c804eb..e54f6fd7609 100644
--- a/test/geojson.test.js
+++ b/test/geojson.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/gh-1408.test.js b/test/gh-1408.test.js
index a6684ac1ded..7a2d86cef57 100644
--- a/test/gh-1408.test.js
+++ b/test/gh-1408.test.js
@@ -5,9 +5,10 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/index.test.js b/test/index.test.js
index e9e7eee8a01..5e3c643cd4f 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -1,9 +1,10 @@
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 const stream = require('stream');
 
 const collection = 'blogposts_' + random();
diff --git a/test/model.aggregate.test.js b/test/model.aggregate.test.js
index b740c40b499..2272f23fe30 100644
--- a/test/model.aggregate.test.js
+++ b/test/model.aggregate.test.js
@@ -5,10 +5,11 @@
 
 'use strict';
 
+const start = require('./common');
+
 const Aggregate = require('../lib/aggregate');
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.create.test.js b/test/model.create.test.js
index a22b1da92e7..51630b0a654 100644
--- a/test/model.create.test.js
+++ b/test/model.create.test.js
@@ -5,9 +5,11 @@
  */
 
 const start = require('./common');
+
 const assert = require('assert');
-const mongoose = start.mongoose;
 const random = require('../lib/utils').random;
+
+const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 const DocumentObjectId = mongoose.Types.ObjectId;
 
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 9132cc78e04..83c55da1a8c 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -5,6 +5,7 @@
 'use strict';
 
 const start = require('./common');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 const assert = require('assert');
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 1b50f81a201..429c5c18620 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -4,11 +4,12 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const clone = require('../lib/utils').clone;
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 const util = require('util');
 
 const mongoose = start.mongoose;
diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index 9834cd45b3d..d2e2d454436 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -4,10 +4,11 @@
 
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.findOneAndDelete.test.js b/test/model.findOneAndDelete.test.js
index 210a992b4d7..4c6e80f789d 100644
--- a/test/model.findOneAndDelete.test.js
+++ b/test/model.findOneAndDelete.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
diff --git a/test/model.findOneAndRemove.test.js b/test/model.findOneAndRemove.test.js
index b73af6d83e4..901e9e05885 100644
--- a/test/model.findOneAndRemove.test.js
+++ b/test/model.findOneAndRemove.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
diff --git a/test/model.findOneAndReplace.test.js b/test/model.findOneAndReplace.test.js
index 11e7dfbd8fe..b3054153f5f 100644
--- a/test/model.findOneAndReplace.test.js
+++ b/test/model.findOneAndReplace.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index a59d3d2e9a6..efa5091ba73 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -4,8 +4,9 @@
  * Test dependencies.
  */
 
-const CastError = require('../lib/error/cast');
 const start = require('./common');
+
+const CastError = require('../lib/error/cast');
 const assert = require('assert');
 const mongoose = start.mongoose;
 const random = require('../lib/utils').random;
diff --git a/test/model.geosearch.test.js b/test/model.geosearch.test.js
index a0cee8b299c..3848240091f 100644
--- a/test/model.geosearch.test.js
+++ b/test/model.geosearch.test.js
@@ -1,8 +1,9 @@
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.hydrate.test.js b/test/model.hydrate.test.js
index 83a0319e323..e7f0134d61a 100644
--- a/test/model.hydrate.test.js
+++ b/test/model.hydrate.test.js
@@ -4,9 +4,10 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 const DocumentObjectId = mongoose.Types.ObjectId;
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 15891a4b2a9..113980002cd 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.mapreduce.test.js b/test/model.mapreduce.test.js
index 59777ed7fef..7b69d8d1ecc 100644
--- a/test/model.mapreduce.test.js
+++ b/test/model.mapreduce.test.js
@@ -5,9 +5,10 @@
 
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.middleware.test.js b/test/model.middleware.test.js
index e92ade6cb11..84d0abe869e 100644
--- a/test/model.middleware.test.js
+++ b/test/model.middleware.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.populate.divergent.test.js b/test/model.populate.divergent.test.js
index 891b5c7f78c..49b989231ff 100644
--- a/test/model.populate.divergent.test.js
+++ b/test/model.populate.divergent.test.js
@@ -5,8 +5,9 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
+
+const assert = require('assert');
 const utils = require('../lib/utils');
 
 const mongoose = start.mongoose;
diff --git a/test/model.populate.setting.test.js b/test/model.populate.setting.test.js
index b8c7307b6b4..e5b4c8be7a9 100644
--- a/test/model.populate.setting.test.js
+++ b/test/model.populate.setting.test.js
@@ -6,9 +6,10 @@
 
 'use strict';
 
+const start = require('./common');
+
 const Buffer = require('safe-buffer').Buffer;
 const assert = require('assert');
-const start = require('./common');
 const utils = require('../lib/utils');
 
 const mongoose = start.mongoose;
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index eaf72afdbf7..8abdabb8a2c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 const utils = require('../lib/utils');
 const Buffer = require('safe-buffer').Buffer;
 
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index 153d6b83c0a..20b7a5b5a2c 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 9d02ab1ee1d..7c996183098 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -4,11 +4,12 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
diff --git a/test/model.test.js b/test/model.test.js
index bfe47729154..f51cd13e094 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4,10 +4,11 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
diff --git a/test/model.translateAliases.test.js b/test/model.translateAliases.test.js
index 60c9c59f759..944e4fb7bb9 100644
--- a/test/model.translateAliases.test.js
+++ b/test/model.translateAliases.test.js
@@ -4,9 +4,10 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 
 describe('model translate aliases', function() {
diff --git a/test/model.update.test.js b/test/model.update.test.js
index a504a893525..18f3ba25b98 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -4,10 +4,11 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
diff --git a/test/object.create.null.test.js b/test/object.create.null.test.js
index ae852f3301d..27447e033db 100644
--- a/test/object.create.null.test.js
+++ b/test/object.create.null.test.js
@@ -4,9 +4,10 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/plugin.idGetter.test.js b/test/plugin.idGetter.test.js
index 28d7aefd64f..c68497d7a8f 100644
--- a/test/plugin.idGetter.test.js
+++ b/test/plugin.idGetter.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index e4808b624c7..f29b4b6deeb 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -4,9 +4,10 @@
 
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index 9ebebaf3649..dd3d0cab9ed 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 
diff --git a/test/query.test.js b/test/query.test.js
index e670d3016cd..e1533df1a51 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -5,6 +5,7 @@
  */
 
 const start = require('./common');
+
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
diff --git a/test/query.toconstructor.test.js b/test/query.toconstructor.test.js
index 5c933043780..647278c02cf 100644
--- a/test/query.toconstructor.test.js
+++ b/test/query.toconstructor.test.js
@@ -1,10 +1,11 @@
 'use strict';
 
+const start = require('./common');
+
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index ef16af91039..41b7e81d20e 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -4,8 +4,9 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
+
+const assert = require('assert');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
diff --git a/test/schema.boolean.test.js b/test/schema.boolean.test.js
index c5e759b6c77..9d15ef88604 100644
--- a/test/schema.boolean.test.js
+++ b/test/schema.boolean.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/schema.date.test.js b/test/schema.date.test.js
index aea430d3232..227786469a7 100644
--- a/test/schema.date.test.js
+++ b/test/schema.date.test.js
@@ -1,8 +1,9 @@
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/schema.documentarray.test.js b/test/schema.documentarray.test.js
index d6e34182b0b..208446dddeb 100644
--- a/test/schema.documentarray.test.js
+++ b/test/schema.documentarray.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/schema.mixed.test.js b/test/schema.mixed.test.js
index 6687b81bdc6..6a5fc1b97b3 100644
--- a/test/schema.mixed.test.js
+++ b/test/schema.mixed.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = new start.mongoose.Mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/schema.onthefly.test.js b/test/schema.onthefly.test.js
index caf524e658b..d20ed690a65 100644
--- a/test/schema.onthefly.test.js
+++ b/test/schema.onthefly.test.js
@@ -1,8 +1,9 @@
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/schema.select.test.js b/test/schema.select.test.js
index 1eb52b8ac9c..f88c8e3a3db 100644
--- a/test/schema.select.test.js
+++ b/test/schema.select.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
diff --git a/test/schema.test.js b/test/schema.test.js
index 62a813408bf..6cc36b8218e 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -5,6 +5,7 @@
  */
 
 const start = require('./common');
+
 const mongoose = start.mongoose;
 const assert = require('assert');
 const Schema = mongoose.Schema;
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index 959134494d2..60cc3630456 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -4,9 +4,10 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/schema.type.test.js b/test/schema.type.test.js
index dcd21284ede..b1c37594576 100644
--- a/test/schema.type.test.js
+++ b/test/schema.type.test.js
@@ -5,6 +5,7 @@
  */
 
 const mongoose = require('./common').mongoose;
+
 const assert = require('assert');
 
 const Schema = mongoose.Schema;
diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index 77239c7122a..6b689ef052a 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -4,10 +4,11 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const Promise = require('bluebird');
 const assert = require('assert');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/schematype.cast.test.js b/test/schematype.cast.test.js
index 2007b52739a..e7cb29da704 100644
--- a/test/schematype.cast.test.js
+++ b/test/schematype.cast.test.js
@@ -1,5 +1,7 @@
 'use strict';
 
+require('./common');
+
 const ObjectId = require('bson').ObjectId;
 const Schema = require('../lib/schema');
 const assert = require('assert');
diff --git a/test/services.query.test.js b/test/services.query.test.js
index ff2616c64bf..a79008893c2 100644
--- a/test/services.query.test.js
+++ b/test/services.query.test.js
@@ -1,5 +1,7 @@
 'use strict';
 
+require('./common');
+
 const Query = require('../lib/query');
 const Schema = require('../lib/schema');
 const assert = require('assert');
diff --git a/test/shard.test.js b/test/shard.test.js
index 753d207885a..b70aff23fb2 100644
--- a/test/shard.test.js
+++ b/test/shard.test.js
@@ -1,9 +1,10 @@
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const chalk = require('chalk');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index e3e8f103518..2c3ab4fddec 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -1,8 +1,9 @@
 'use strict';
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/types.array.test.js b/test/types.array.test.js
index 449634dd3ae..fe87c82eeaa 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -4,13 +4,14 @@
 
 'use strict';
 
+const start = require('./common');
+
 const Buffer = require('safe-buffer').Buffer;
 const assert = require('assert');
 const co = require('co');
 const mongodb = require('mongodb');
 const mongoose = require('./common').mongoose;
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const MongooseArray = mongoose.Types.Array;
 const Schema = mongoose.Schema;
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index b1c5d4f56f5..a888af52c33 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -4,11 +4,12 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const Buffer = require('safe-buffer').Buffer;
 const assert = require('assert');
 const mongoose = require('./common').mongoose;
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const MongooseBuffer = mongoose.Types.Buffer;
 const Schema = mongoose.Schema;
diff --git a/test/types.decimal128.test.js b/test/types.decimal128.test.js
index 702444a9bfb..e226d5195c3 100644
--- a/test/types.decimal128.test.js
+++ b/test/types.decimal128.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/types.document.test.js b/test/types.document.test.js
index e9f155ab50d..57408268740 100644
--- a/test/types.document.test.js
+++ b/test/types.document.test.js
@@ -5,8 +5,9 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
+
+const assert = require('assert');
 const mongoose = start.mongoose;
 const EmbeddedDocument = require('../lib/types/embedded');
 const EventEmitter = require('events').EventEmitter;
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 4195f06d531..e367250c062 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -4,13 +4,14 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const DocumentArray = require('../lib/types/documentarray');
 const EmbeddedDocument = require('../lib/types/embedded');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
 const setValue = require('../lib/utils').setValue;
-const start = require('./common');
 
 const mongoose = require('./common').mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/types.embeddeddocument.test.js b/test/types.embeddeddocument.test.js
index 0cb15c89197..9dc078877fe 100644
--- a/test/types.embeddeddocument.test.js
+++ b/test/types.embeddeddocument.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 34a72d3ee04..5b3c2121e39 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/types.number.test.js b/test/types.number.test.js
index 3ade9579897..fa8b152f6e6 100644
--- a/test/types.number.test.js
+++ b/test/types.number.test.js
@@ -4,9 +4,10 @@
  * Module dependencies.
  */
 
-const assert = require('assert');
 const mongoose = require('./common').mongoose;
 
+const assert = require('assert');
+
 const SchemaNumber = mongoose.Schema.Types.Number;
 
 /**
diff --git a/test/types.subdocument.test.js b/test/types.subdocument.test.js
index 43747660885..2c583625e39 100644
--- a/test/types.subdocument.test.js
+++ b/test/types.subdocument.test.js
@@ -5,9 +5,10 @@
 
 'use strict';
 
-const assert = require('assert');
 const start = require('./common');
 
+const assert = require('assert');
+
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
diff --git a/test/updateValidators.unit.test.js b/test/updateValidators.unit.test.js
index 6d5820f71d0..d92887e82c1 100644
--- a/test/updateValidators.unit.test.js
+++ b/test/updateValidators.unit.test.js
@@ -1,5 +1,7 @@
 'use strict';
 
+require('./common');
+
 const Schema = require('../lib/schema');
 const assert = require('assert');
 const updateValidators = require('../lib/helpers/updateValidators');
diff --git a/test/utils.test.js b/test/utils.test.js
index 9d2e92f1048..3fe9ac31a03 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -4,12 +4,13 @@
  * Module dependencies.
  */
 
+const start = require('./common');
+
 const Buffer = require('safe-buffer').Buffer;
 const MongooseBuffer = require('../lib/types/buffer');
 const ObjectId = require('../lib/types/objectid');
 const StateMachine = require('../lib/statemachine');
 const assert = require('assert');
-const start = require('./common');
 const utils = require('../lib/utils');
 
 const mongoose = start.mongoose;
diff --git a/test/versioning.test.js b/test/versioning.test.js
index 0806894eb90..e5b127d1d3b 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -4,10 +4,11 @@
  * Test dependencies.
  */
 
+const start = require('./common');
+
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
-const start = require('./common');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;

From e9c69b3c40eaf7434af3446d10ced7a87dfc858c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 14:40:48 -0500
Subject: [PATCH 0151/2348] perf(cursor): remove unnecessary `setTimeout()` in
 `eachAsync()`, 4x speedup in basic benchmarks

Fix #8310
---
 lib/helpers/cursor/eachAsync.js | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 472dbeee187..95a38dbf93a 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -99,13 +99,11 @@ function asyncQueue() {
   };
 
   function _step() {
-    setTimeout(() => {
-      inProgress = null;
-      if (_queue.length > 0) {
-        inProgress = id++;
-        const fn = _queue.shift();
-        fn(_step);
-      }
-    }, 0);
+    inProgress = null;
+    if (_queue.length > 0) {
+      inProgress = id++;
+      const fn = _queue.shift();
+      fn(_step);
+    }
   }
 }
\ No newline at end of file

From c7676a9e47c50fcb3cbc8d9294ab5ebf7335772e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 19:05:12 -0500
Subject: [PATCH 0152/2348] feat(aggregate): run pre/post aggregate hooks on
 `explain()`

Fix #5887
---
 lib/aggregate.js       | 34 +++++++++++++++++++++++++---------
 test/aggregate.test.js | 24 ++++++++++++++++++++++++
 2 files changed, 49 insertions(+), 9 deletions(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index b9d08af3181..ea3b5f1e6a4 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -697,6 +697,8 @@ Aggregate.prototype.redact = function(expression, thenExpr, elseExpr) {
  */
 
 Aggregate.prototype.explain = function(callback) {
+  const model = this._model;
+
   return utils.promiseOrCallback(callback, cb => {
     if (!this._pipeline.length) {
       const err = new Error('Aggregate has empty pipeline');
@@ -705,15 +707,29 @@ Aggregate.prototype.explain = function(callback) {
 
     prepareDiscriminatorPipeline(this);
 
-    this._model.collection.
-      aggregate(this._pipeline, this.options || {}).
-      explain(function(error, result) {
-        if (error) {
-          return cb(error);
-        }
-        cb(null, result);
-      });
-  }, this._model.events);
+    model.hooks.execPre('aggregate', this, error => {
+      if (error) {
+        const _opts = { error: error };
+        return model.hooks.execPost('aggregate', this, [null], _opts, error => {
+          cb(error);
+        });
+      }
+
+      this.options.explain = true;
+
+      model.collection.
+        aggregate(this._pipeline, this.options || {}).
+        explain((error, result) => {
+          const _opts = { error: error };
+          return model.hooks.execPost('aggregate', this, [result], _opts, error => {
+            if (error) {
+              return cb(error);
+            }
+            return cb(null, result);
+          });
+        });
+    });
+  }, model.events);
 };
 
 /**
diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 3c417deb53b..54c85e8a982 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -1146,6 +1146,30 @@ describe('aggregate: ', function() {
             done();
           });
       });
+
+      it('with explain() (gh-5887)', function() {
+        const s = new Schema({ name: String });
+
+        let calledPre = 0;
+        const calledPost = [];
+        s.pre('aggregate', function(next) {
+          ++calledPre;
+          next();
+        });
+        s.post('aggregate', function(res, next) {
+          calledPost.push(res);
+          next();
+        });
+
+        const M = db.model('gh5887_cursor', s);
+
+        return M.aggregate([{ $match: { name: 'test' } }]).explain().
+          then(() => {
+            assert.equal(calledPre, 1);
+            assert.equal(calledPost.length, 1);
+            assert.ok(calledPost[0].queryPlanner);
+          });
+      });
     });
 
     it('readPref from schema (gh-5522)', function(done) {

From c2532348cc168a86ead2bf104cd622a9544bf75e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 19:17:28 -0500
Subject: [PATCH 0153/2348] test(aggregate): fix tests

---
 test/aggregate.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 54c85e8a982..c12c9d6b44d 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -900,7 +900,7 @@ describe('aggregate: ', function() {
             assert.ifError(err1);
             assert.ok(output);
             // make sure we got explain output
-            assert.ok(output.stages);
+            assert.ok(output.stages || output.queryPlanner);
 
             done();
           });
@@ -1167,7 +1167,7 @@ describe('aggregate: ', function() {
           then(() => {
             assert.equal(calledPre, 1);
             assert.equal(calledPost.length, 1);
-            assert.ok(calledPost[0].queryPlanner);
+            assert.ok(calledPost[0].stages || calledPost[0].queryPlanner);
           });
       });
     });

From b36259c1b76efa2d7db911dc0e811b2efb181319 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Nov 2019 22:02:08 -0500
Subject: [PATCH 0154/2348] feat(query): add Query#mongooseOptions() function

Fix #8296
---
 lib/query.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/lib/query.js b/lib/query.js
index 370d5add3e9..be4d5613142 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1687,6 +1687,39 @@ Query.prototype.lean = function(v) {
   return this;
 };
 
+/**
+ * Returns an object containing the Mongoose-specific options for this query,
+ * including `lean` and `populate`.
+ *
+ * Mongoose-specific options are different from normal options (`sort`, `limit`, etc.)
+ * because they are **not** sent to the MongoDB server.
+ *
+ * ####Example:
+ *
+ *     const q = new Query();
+ *     q.mongooseOptions().lean; // undefined
+ *
+ *     q.lean();
+ *     q.mongooseOptions().lean; // true
+ *
+ * This function is useful for writing [query middleware](/docs/middleware.html).
+ * Below is a full list of properties the return value from this function may have:
+ *
+ * - `populate`
+ * - `lean`
+ * - `omitUndefined`
+ * - `strict`
+ * - `nearSphere`
+ * - `useFindAndModify`
+ *
+ * @return {Object} Mongoose-specific options
+ * @param public
+ */
+
+Query.prototype.mongooseOptions = function() {
+  return this._mongooseOptions;
+};
+
 /**
  * Adds a `$set` to this query's update without changing the operation.
  * This is useful for query middleware so you can add an update regardless

From 689791b6445cd8d1f7deb422bd14f6ebdb1c14a1 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Sun, 10 Nov 2019 13:46:53 -0500
Subject: [PATCH 0155/2348] Illustrate Promise API, move Import after Install

---
 README.md | 35 ++++++++++++++++++++---------------
 1 file changed, 20 insertions(+), 15 deletions(-)

diff --git a/README.md b/README.md
index 11839b87e3e..b9a2c71e12f 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Mongoose
 
-Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed to work in an asynchronous environment.
+Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed to work in an asynchronous environment. It has both a callbacks and Promise-style API.
 
 [![Slack Status](http://slack.mongoosejs.io/badge.svg)](http://slack.mongoosejs.io)
 [![Build Status](https://api.travis-ci.org/Automattic/mongoose.svg?branch=master)](https://travis-ci.org/Automattic/mongoose)
@@ -22,16 +22,6 @@ Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed
   - [Help Forum](http://groups.google.com/group/mongoose-orm)
   - [MongoDB Support](https://docs.mongodb.org/manual/support/)
 
-## Importing
-
-```javascript
-// Using Node.js `require()`
-const mongoose = require('mongoose');
-
-// Using ES6 imports
-import mongoose from 'mongoose';
-```
-
 ## Plugins
 
 Check out the [plugins search site](http://plugins.mongoosejs.io/) to see hundreds of related modules from the community. Next, learn how to write your own plugin from the [docs](http://mongoosejs.com/docs/plugins.html) or [this blog post](http://thecodebarbarian.com/2015/03/06/guide-to-mongoose-plugins).
@@ -55,6 +45,16 @@ First install [node.js](http://nodejs.org/) and [mongodb](https://www.mongodb.or
 $ npm install mongoose
 ```
 
+## Importing
+
+```javascript
+// Using Node.js `require()`
+const mongoose = require('mongoose');
+
+// Using ES6 imports
+import mongoose from 'mongoose';
+```
+
 ## Overview
 
 ### Connecting to MongoDB
@@ -64,9 +64,7 @@ First, we need to define a connection. If your app uses only one database, you s
 Both `connect` and `createConnection` take a `mongodb://` URI, or the parameters `host, database, port, options`.
 
 ```js
-const mongoose = require('mongoose');
-
-mongoose.connect('mongodb://localhost/my_database', {
+await mongoose.connect('mongodb://localhost/my_database', {
   useNewUrlParser: true,
   useUnifiedTopology: true
 });
@@ -172,7 +170,14 @@ MyModel.find({}, function (err, docs) {
 });
 ```
 
-You can also `findOne`, `findById`, `update`, etc. For more details check out [the docs](http://mongoosejs.com/docs/queries.html).
+You can also `findOne`, `findById`, `update`, etc.
+
+```js
+const instance = await MyModel.findOne({ ... });
+console.log(instance.my.key);  // 'hello'
+```
+
+For more details check out [the docs](http://mongoosejs.com/docs/queries.html).
 
 **Important!** If you opened a separate connection using `mongoose.createConnection()` but attempt to access the model through `mongoose.model('ModelName')` it will not work as expected since it is not hooked up to an active db connection. In this case access your model through the connection you created:
 

From 85120952cd0f6426f43d769d3ae5edf1376651b2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 10 Nov 2019 21:24:50 -0500
Subject: [PATCH 0156/2348] feat(schema): group indexes defined in schema path
 with the same name

Fix #6499
---
 lib/helpers/schema/getIndexes.js | 14 +++++++++++++-
 test/schema.test.js              | 13 +++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index 899d309b5ed..e501456952c 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -12,6 +12,7 @@ module.exports = function getIndexes(schema) {
   let indexes = [];
   const schemaStack = new WeakMap();
   const indexTypes = schema.constructor.indexTypes;
+  const indexByName = new Map();
 
   const collectIndexes = function(schema, prefix, baseSchema) {
     // Ignore infinitely nested schemas, if we've already seen this schema
@@ -80,7 +81,18 @@ module.exports = function getIndexes(schema) {
           options.background = true;
         }
 
-        indexes.push([field, options]);
+        const indexName = options && options.name;
+        if (typeof indexName === 'string') {
+          if (indexByName.has(indexName)) {
+            Object.assign(indexByName.get(indexName), field);
+          } else {
+            indexes.push([field, options]);
+            indexByName.set(indexName, field);
+          }
+        } else {
+          indexes.push([field, options]);
+          indexByName.set(indexName, field);
+        }
       }
     }
 
diff --git a/test/schema.test.js b/test/schema.test.js
index 6cc36b8218e..30ca6a7c59d 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -845,6 +845,19 @@ describe('schema', function() {
         done();
       });
 
+      it('compound based on name (gh-6499)', function() {
+        const testSchema = new Schema({
+          prop1: { type: String, index: { name: 'test1' } },
+          prop2: { type: Number, index: true },
+          prop3: { type: String, index: { name: 'test1' } }
+        });
+
+        const indexes = testSchema.indexes();
+        assert.equal(indexes.length, 2);
+        assert.deepEqual(indexes[0][0], { prop1: 1, prop3: 1 });
+        assert.deepEqual(indexes[1][0], { prop2: 1 });
+      });
+
       it('with single nested doc (gh-6113)', function(done) {
         const pointSchema = new Schema({
           type: {

From 9e317105f535ce424e260514ad34672a496a351f Mon Sep 17 00:00:00 2001
From: "Andrew Stiegmann (stieg)" <andrew.stiegmann@airfordable.com>
Date: Sun, 10 Nov 2019 20:42:52 -1000
Subject: [PATCH 0157/2348] build(test) Improve test target

Adds a mocha section to package.json to allow the removal of the
file path arguments in the test script target for mocha. Doing this
enables the developer to now invoke testing on a single file more
easily like so:

`$ npm test test/utils.test.js`
---
 package.json | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 0e59ddfd134..793e4570891 100644
--- a/package.json
+++ b/package.json
@@ -73,7 +73,7 @@
     "lint": "eslint .",
     "release": "git pull && git push origin master --tags && npm publish",
     "release-legacy": "git pull origin 4.x && git push origin 4.x --tags && npm publish --tag legacy",
-    "test": "mocha --exit test/*.test.js test/**/*.test.js",
+    "test": "mocha --exit",
     "test-cov": "nyc --reporter=html --reporter=text npm test"
   },
   "main": "./index.js",
@@ -142,6 +142,10 @@
           "message": "Don't use Mocha's global context"
         }
       ]
+    },
+    "mocha": {
+      "extension": ["test.js"],
+      "watch-files": ["test/**/*.js"]
     }
   }
 }

From 2753e1c38635bfd93ad586cfb4abd6e7381224a5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 11 Nov 2019 13:32:49 -0500
Subject: [PATCH 0158/2348] chore: fix package.json config for #8322

---
 package.json | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/package.json b/package.json
index 793e4570891..df8c25b273e 100644
--- a/package.json
+++ b/package.json
@@ -89,6 +89,14 @@
   },
   "homepage": "https://mongoosejs.com",
   "browser": "./browser.js",
+  "mocha": {
+    "extension": [
+      "test.js"
+    ],
+    "watch-files": [
+      "test/**/*.js"
+    ]
+  },
   "eslintConfig": {
     "extends": [
       "eslint:recommended"
@@ -142,10 +150,6 @@
           "message": "Don't use Mocha's global context"
         }
       ]
-    },
-    "mocha": {
-      "extension": ["test.js"],
-      "watch-files": ["test/**/*.js"]
     }
   }
 }

From 95b25cec12e73ce5d34cef06023b75c2e0441f33 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 11 Nov 2019 13:43:38 -0500
Subject: [PATCH 0159/2348] chore: release 5.7.10

---
 History.md   | 6 ++++++
 README.md    | 2 +-
 package.json | 2 +-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/History.md b/History.md
index 6db11f0fcfb..e634a8e41ff 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.7.10 / 2019-11-11
+===================
+ * perf(cursor): remove unnecessary `setTimeout()` in `eachAsync()`, 4x speedup in basic benchmarks #8310
+ * docs(README): re-order sections for better readability #8321 [dandv](https://github.com/dandv)
+ * chore: make npm test not hard-code file paths #8322 [stieg](https://github.com/stieg)
+
 5.7.9 / 2019-11-08
 ==================
  * fix(schema): support setting schema path to an instance of SchemaTypeOptions to fix integration with mongoose-i18n-localize #8297 #8292
diff --git a/README.md b/README.md
index b9a2c71e12f..ebfcbb93bcd 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Mongoose
 
-Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed to work in an asynchronous environment. It has both a callbacks and Promise-style API.
+Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed to work in an asynchronous environment. Mongoose supports both promises and callbacks.
 
 [![Slack Status](http://slack.mongoosejs.io/badge.svg)](http://slack.mongoosejs.io)
 [![Build Status](https://api.travis-ci.org/Automattic/mongoose.svg?branch=master)](https://travis-ci.org/Automattic/mongoose)
diff --git a/package.json b/package.json
index df8c25b273e..e1aa1713044 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.9",
+  "version": "5.7.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From de583bb44655a7055c17e455c3853b3eb81af6f2 Mon Sep 17 00:00:00 2001
From: Hsu Ching Feng <5862369+Fonger@users.noreply.github.com>
Date: Tue, 12 Nov 2019 17:50:42 +0800
Subject: [PATCH 0160/2348] fix(model): delete $versionError after saving to
 prevent memory leak

The original fix in PR #8048 has a typo. This really fix the issue.
---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 6f10c5f9ee1..ba982da837d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -465,7 +465,7 @@ Model.prototype.save = function(options, fn) {
     this.$__save(options, error => {
       this.$__.saving = undefined;
       delete this.$__.saveOptions;
-      delete this.$__.versionError;
+      delete this.$__.$versionError;
 
       if (error) {
         this.$__handleReject(error);

From 6c1dcb28cc6eb528a3710f64fe3cc95ea7e628ff Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 Nov 2019 15:50:42 +0200
Subject: [PATCH 0161/2348] Fixes #8331

---
 lib/helpers/model/castBulkWrite.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index f4e15648979..f724afb0b31 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -34,6 +34,9 @@ module.exports = function castBulkWrite(model, op, options) {
     op = op['updateOne'];
     return (callback) => {
       try {
+        if (!op['filter']) throw new Error('Must provide a filter object.');
+        if (!op['update']) throw new Error('Must provide an update object.');
+
         op['filter'] = cast(model.schema, op['filter']);
         op['update'] = castUpdate(model.schema, op['update'], {
           strict: model.schema.options.strict,
@@ -61,6 +64,9 @@ module.exports = function castBulkWrite(model, op, options) {
     op = op['updateMany'];
     return (callback) => {
       try {
+        if (!op['filter']) throw new Error('Must provide a filter object.');
+        if (!op['update']) throw new Error('Must provide an update object.');
+
         op['filter'] = cast(model.schema, op['filter']);
         op['update'] = castUpdate(model.schema, op['update'], {
           strict: model.schema.options.strict,

From a91dc93a3750d024899ac8b3a56a9d2b8f682759 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 Nov 2019 16:04:54 +0200
Subject: [PATCH 0162/2348] Add test for #8331

---
 test/model.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index a0bf8dc8960..ce2ceddb56e 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5671,6 +5671,34 @@ describe('Model', function() {
           then(() => Model.findOne()).
           then(doc => assert.equal(doc.nested.name, 'foo'));
       });
+
+      it('throws an error if no update object is provided (gh-8331)', function() {
+        const userSchema = new Schema({ name: { type: String, required: true } });
+        const User = db.model('gh8331', userSchema);
+
+        return co(function*() {
+          const createdUser = yield User.create({ name: 'Hafez' });
+          let threw = false;
+          try {
+            yield User.bulkWrite([{
+              updateOne: {
+                filter: { _id: createdUser._id }
+              }
+            }]);
+          }
+          catch (err) {
+            threw = true;
+            assert.equal(err.message, 'Must provide an update object.');
+          }
+          finally {
+            assert.equal(threw, true);
+
+            const userAfterUpdate = yield User.findOne({ _id: createdUser._id });
+
+            assert.equal(userAfterUpdate.name, 'Hafez', 'Document data is not wiped if no update object is provided.');
+          }
+        });
+      });
     });
 
     it('insertMany with Decimal (gh-5190)', function(done) {

From 51d7c34417afe2fcef1adcbfa6a5fa3a69f31f60 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 Nov 2019 21:14:58 +0200
Subject: [PATCH 0163/2348] Fixes #6899

---
 lib/index.js        |  3 +++
 lib/validoptions.js | 29 +++++++++++++++++++++++++++++
 test/index.test.js  | 14 ++++++++++++++
 3 files changed, 46 insertions(+)
 create mode 100644 lib/validoptions.js

diff --git a/lib/index.js b/lib/index.js
index 6fbfb932e5c..ddc4978b33a 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -20,6 +20,7 @@ const SchemaType = require('./schematype');
 const SchemaTypes = require('./schema/index');
 const VirtualType = require('./virtualtype');
 const STATES = require('./connectionstate');
+const VALID_OPTIONS = require('./validoptions');
 const Types = require('./types');
 const Query = require('./query');
 const Model = require('./model');
@@ -168,6 +169,8 @@ Mongoose.prototype.driver = require('./driver');
 Mongoose.prototype.set = function(key, value) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
+  if (!VALID_OPTIONS.includes(key)) throw new Error(`\`${key}\` is an invaid option.`);
+
   if (arguments.length === 1) {
     return _mongoose.options[key];
   }
diff --git a/lib/validoptions.js b/lib/validoptions.js
new file mode 100644
index 00000000000..7ae1a8bb874
--- /dev/null
+++ b/lib/validoptions.js
@@ -0,0 +1,29 @@
+
+/*!
+ * Valid mongoose options
+ */
+
+'use strict';
+
+const VALID_OPTIONS = Object.freeze([
+  'applyPluginsToChildSchemas',
+  'applyPluginsToDiscriminators',
+  'autoIndex',
+  'bufferCommands',
+  'cloneSchemas',
+  'debug',
+  'maxTimeMS',
+  'objectIdGetter',
+  'runValidators',
+  'selectPopulatedPaths',
+  'strict',
+  'toJSON',
+  'toObject',
+  'useCreateIndex',
+  'useFindAndModify',
+  'useNewUrlParser',
+  'usePushEach',
+  'useUnifiedTopology'
+]);
+
+module.exports = VALID_OPTIONS;
\ No newline at end of file
diff --git a/test/index.test.js b/test/index.test.js
index e9e7eee8a01..2bc2516181c 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -495,6 +495,20 @@ describe('mongoose module:', function() {
     return Promise.resolve();
   });
 
+  it('throws errors on setting invalid options (gh-6899)', function() {
+    let threw = false;
+    try {
+      mongoose.set('someInvalidOption', true);
+    }
+    catch (err) {
+      assert.equal(err.message, '`someInvalidOption` is an invalid option.');
+      threw = true;
+    }
+    finally {
+      assert.equal(threw, true);
+    }
+  });
+
   describe('disconnection of all connections', function() {
     this.timeout(10000);
 

From 132ad41d1a28002b3e8fc675d60d5e84fd17519c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 Nov 2019 21:20:51 +0200
Subject: [PATCH 0164/2348] Fix typo

---
 lib/index.js       | 2 +-
 test/index.test.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index ddc4978b33a..d262c090858 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -169,7 +169,7 @@ Mongoose.prototype.driver = require('./driver');
 Mongoose.prototype.set = function(key, value) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  if (!VALID_OPTIONS.includes(key)) throw new Error(`\`${key}\` is an invaid option.`);
+  if (!VALID_OPTIONS.includes(key)) throw new Error(`\`${key}\` is an invalid option.`);
 
   if (arguments.length === 1) {
     return _mongoose.options[key];
diff --git a/test/index.test.js b/test/index.test.js
index 2bc2516181c..14d78e926ef 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -495,7 +495,7 @@ describe('mongoose module:', function() {
     return Promise.resolve();
   });
 
-  it('throws errors on setting invalid options (gh-6899)', function() {
+  it('throws an error on setting invalid options (gh-6899)', function() {
     let threw = false;
     try {
       mongoose.set('someInvalidOption', true);

From 91ea10e0a509a8732723e3806db87d860e707b99 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Nov 2019 16:22:08 -0500
Subject: [PATCH 0165/2348] fix: upgrade to mongodb driver 3.3.4

Fix #8337
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index e1aa1713044..0449d663b3e 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.3.3",
+    "mongodb": "3.3.4",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From 4ec852d28817e01f3119b2eb04618adc6d79e90e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Nov 2019 17:49:07 -0500
Subject: [PATCH 0166/2348] fix(connection): bubble up connected/disconnected
 events with unified topology

---
 lib/connection.js       | 6 ++++++
 test/connection.test.js | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 785796c1f50..6cdd4e64dc5 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -643,6 +643,12 @@ Connection.prototype.openUri = function(uri, options, callback) {
       if (options.useUnifiedTopology) {
         if (type === 'Single') {
           const server = Array.from(db.s.topology.s.servers.values())[0];
+          server.s.pool.on('close', () => {
+            _this.readyState = STATES.disconnected;
+          });
+          server.s.topology.on('serverHeartbeatSucceeded', () => {
+            _handleReconnect();
+          });
           server.s.pool.on('reconnect', () => {
             _handleReconnect();
           });
diff --git a/test/connection.test.js b/test/connection.test.js
index 6a4a61a4697..f7c4a4e4852 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -189,7 +189,7 @@ describe('connections:', function() {
         let numReconnected = 0;
         let numReconnect = 0;
         let numClose = 0;
-        const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest', {
+        const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest?heartbeatfrequencyms=1000', {
           useNewUrlParser: true,
           useUnifiedTopology: true
         });

From c4fc7b25a1b520bebe6a8656ede8a173332c0ded Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 Nov 2019 01:31:23 +0200
Subject: [PATCH 0167/2348] Add valid options to fix test case

---
 test/index.test.js | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/index.test.js b/test/index.test.js
index 14d78e926ef..0ab58f82537 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -102,12 +102,12 @@ describe('mongoose module:', function() {
   it('{g,s}etting options', function(done) {
     const mongoose = new Mongoose();
 
-    mongoose.set('a', 'b');
-    mongoose.set('long option', 'c');
+    mongoose.set('runValidators', 'b');
+    mongoose.set('useNewUrlParser', 'c');
 
-    assert.equal(mongoose.get('a'), 'b');
-    assert.equal(mongoose.set('a'), 'b');
-    assert.equal(mongoose.get('long option'), 'c');
+    assert.equal(mongoose.get('runValidators'), 'b');
+    assert.equal(mongoose.set('runValidators'), 'b');
+    assert.equal(mongoose.get('useNewUrlParser'), 'c');
     done();
   });
 
@@ -495,7 +495,7 @@ describe('mongoose module:', function() {
     return Promise.resolve();
   });
 
-  it('throws an error on setting invalid options (gh-6899)', function() {
+  xit('throws an error on setting invalid options (gh-6899)', function() {
     let threw = false;
     try {
       mongoose.set('someInvalidOption', true);

From 50f81425468b52708f1dc1ec49acbd15e92c1d5f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 Nov 2019 01:40:29 +0200
Subject: [PATCH 0168/2348] Make test pass for Node version 4 & 5

---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index d262c090858..467c5b39c1a 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -169,7 +169,7 @@ Mongoose.prototype.driver = require('./driver');
 Mongoose.prototype.set = function(key, value) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  if (!VALID_OPTIONS.includes(key)) throw new Error(`\`${key}\` is an invalid option.`);
+  if (!VALID_OPTIONS.indexOf(key) !== -1) throw new Error(`\`${key}\` is an invalid option.`);
 
   if (arguments.length === 1) {
     return _mongoose.options[key];

From 4035d43b99956b79f9c033f7cb74160b9eae33e2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 Nov 2019 01:41:27 +0200
Subject: [PATCH 0169/2348] Fix typo

---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index 467c5b39c1a..a24f61f688b 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -169,7 +169,7 @@ Mongoose.prototype.driver = require('./driver');
 Mongoose.prototype.set = function(key, value) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  if (!VALID_OPTIONS.indexOf(key) !== -1) throw new Error(`\`${key}\` is an invalid option.`);
+  if (!VALID_OPTIONS.indexOf(key) === -1) throw new Error(`\`${key}\` is an invalid option.`);
 
   if (arguments.length === 1) {
     return _mongoose.options[key];

From d1cbe0616017a72a45185511dd7786e29cb93be7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 Nov 2019 01:41:46 +0200
Subject: [PATCH 0170/2348] Fix typo

---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index a24f61f688b..595bf8e4bb0 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -169,7 +169,7 @@ Mongoose.prototype.driver = require('./driver');
 Mongoose.prototype.set = function(key, value) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  if (!VALID_OPTIONS.indexOf(key) === -1) throw new Error(`\`${key}\` is an invalid option.`);
+  if (VALID_OPTIONS.indexOf(key) === -1) throw new Error(`\`${key}\` is an invalid option.`);
 
   if (arguments.length === 1) {
     return _mongoose.options[key];

From 0c0833a33de28c40eb56387b87b71d6437d8e413 Mon Sep 17 00:00:00 2001
From: Fonger <5862369+Fonger@users.noreply.github.com>
Date: Thu, 14 Nov 2019 14:18:23 +0800
Subject: [PATCH 0171/2348] test(model): add test for issue #8040 re: #8048
 #8326

---
 test/model.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 0ab154470aa..fc6c2b40a20 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -3816,6 +3816,23 @@ describe('Model', function() {
         });
       });
     });
+    it('should clear $versionError and saveOptions after saved (gh-8040)', function(done) {
+      const schema = new Schema({name: String});
+      const Model = db.model('gh8040', schema);
+      const doc = new Model({
+        name: 'Fonger'
+      });
+
+      const savePromise = doc.save();
+      assert.ok(doc.$__.$versionError);
+      assert.ok(doc.$__.saveOptions);
+
+      savePromise.then(function() {
+        assert.ok(!doc.$__.$versionError);
+        assert.ok(!doc.$__.saveOptions);
+        done();
+      }).catch(done);
+    });
   });
 
 

From e5c6ded7996953b4fe146e6ce9a75041a7849509 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 14 Nov 2019 10:22:55 -0500
Subject: [PATCH 0172/2348] test(connection): fix tests re: #8337

---
 lib/connection.js       | 3 ---
 test/connection.test.js | 2 +-
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 6cdd4e64dc5..a8e418f49a9 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -652,9 +652,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
           server.s.pool.on('reconnect', () => {
             _handleReconnect();
           });
-          server.s.pool.on('reconnectFailed', () => {
-            _this.emit('reconnectFailed');
-          });
           server.s.pool.on('timeout', () => {
             _this.emit('timeout');
           });
diff --git a/test/connection.test.js b/test/connection.test.js
index f7c4a4e4852..16b05ac3305 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -260,7 +260,7 @@ describe('connections:', function() {
           reconnectTries: 3,
           reconnectInterval: 100,
           useNewUrlParser: true,
-          useUnifiedTopology: true
+          useUnifiedTopology: false // reconnectFailed doesn't get emitted with 'useUnifiedTopology'
         });
 
         conn.on('connected', function() {

From 9970a6f21693a90c8c7c2d2c4adc58ff735de677 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 14 Nov 2019 10:35:19 -0500
Subject: [PATCH 0173/2348] chore: release 5.7.11

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index e634a8e41ff..91ae6d36208 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.7.11 / 2019-11-14
+===================
+ * fix: update mongodb driver -> 3.3.4 #8276
+ * fix(model): throw readable error when casting bulkWrite update without a 'filter' or 'update' #8332 #8331 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(connection): bubble up connected/disconnected events with unified topology #8338 #8337
+ * fix(model): delete $versionError after saving #8326 #8048 [Fonger](https://github.com/Fonger)
+ * test(model): add test for issue #8040 #8341 [Fonger](https://github.com/Fonger)
+
 5.7.10 / 2019-11-11
 ===================
  * perf(cursor): remove unnecessary `setTimeout()` in `eachAsync()`, 4x speedup in basic benchmarks #8310
diff --git a/package.json b/package.json
index 0449d663b3e..464125c02a7 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.10",
+  "version": "5.7.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 8b4d868bf93334dfb6ff1380c19fd257a6ed56ab Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 Nov 2019 19:29:38 +0200
Subject: [PATCH 0174/2348] Allow test to run

---
 test/index.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/index.test.js b/test/index.test.js
index 0ab58f82537..7957fdd2c72 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -495,7 +495,7 @@ describe('mongoose module:', function() {
     return Promise.resolve();
   });
 
-  xit('throws an error on setting invalid options (gh-6899)', function() {
+  it('throws an error on setting invalid options (gh-6899)', function() {
     let threw = false;
     try {
       mongoose.set('someInvalidOption', true);

From 10bb6ed2e2218f50fcbcc4657253b64e5b88de6d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 15 Nov 2019 20:00:01 -0500
Subject: [PATCH 0175/2348] chore: now working on 5.7.12

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 464125c02a7..aaa6e1eb422 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.11",
+  "version": "5.7.12-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a821c305114c492ff88ee2f563a7c72da7ec0351 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 15 Nov 2019 20:09:13 -0500
Subject: [PATCH 0176/2348] docs(schema): add Schema#paths docs to public API
 docs

Fix #8340
---
 lib/schema.js | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 73318da0859..014b34479e6 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -235,15 +235,17 @@ Object.defineProperty(Schema.prototype, 'childSchemas', {
 Schema.prototype.obj;
 
 /**
- * Schema as flat paths
+ * The paths defined on this schema. The keys are the top-level paths
+ * in this schema, and the values are instances of the SchemaType class.
  *
  * ####Example:
- *     {
- *         '_id'        : SchemaType,
- *       , 'nested.key' : SchemaType,
- *     }
+ *     const schema = new Schema({ name: String }, { _id: false });
+ *     schema.paths; // { name: SchemaString { ... } }
+ * 
+ *     schema.add({ age: Number });
+ *     schema.paths; // { name: SchemaString { ... }, age: SchemaNumber { ... } }
  *
- * @api private
+ * @api public
  * @property paths
  * @memberOf Schema
  * @instance

From eb235b064fa7b788fda144b521a4278770b4fea9 Mon Sep 17 00:00:00 2001
From: Metin Dumandag <metin@hazelcast.com>
Date: Sat, 16 Nov 2019 17:46:27 +0300
Subject: [PATCH 0177/2348] remove duplicate omitUndefined options

---
 lib/query.js | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 370d5add3e9..4a31e40d50f 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3862,7 +3862,6 @@ Query.prototype._replaceOne = wrapThunk(function(callback) {
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
- * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] params are (error, writeOpResult)
  * @return {Query} this
@@ -3928,7 +3927,6 @@ Query.prototype.update = function(conditions, doc, options, callback) {
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
- * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] params are (error, writeOpResult)
  * @return {Query} this
@@ -3995,7 +3993,6 @@ Query.prototype.updateMany = function(conditions, doc, options, callback) {
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
- * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] params are (error, writeOpResult)
  * @return {Query} this
@@ -4060,7 +4057,6 @@ Query.prototype.updateOne = function(conditions, doc, options, callback) {
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
- * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] params are (error, writeOpResult)
  * @return {Query} this

From 9ce45efc9e3e0641c19d048fceba7c4c493f6c01 Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Sat, 16 Nov 2019 14:22:11 -0800
Subject: [PATCH 0178/2348] feat(browser): pre-compile mongoose/browser

---
 build-browser.js       | 18 ++++++++++
 package.json           |  4 ++-
 test/files/sample.js   |  2 +-
 test/webpack.test.js   | 81 +++++++++++++++++++-----------------------
 webpack.base.config.js | 33 +++++++++++++++++
 webpack.config.js      | 24 +++++++++++++
 6 files changed, 115 insertions(+), 47 deletions(-)
 create mode 100644 build-browser.js
 create mode 100644 webpack.base.config.js
 create mode 100644 webpack.config.js

diff --git a/build-browser.js b/build-browser.js
new file mode 100644
index 00000000000..6f4aa168160
--- /dev/null
+++ b/build-browser.js
@@ -0,0 +1,18 @@
+'use strict';
+
+const config = require('./webpack.config.js');
+const webpack = require('webpack');
+
+const compiler = webpack(config);
+
+console.log('Starting browser build...');
+compiler.run((err, stats) => {
+  if (err) {
+    console.err(stats.toString());
+    console.err('Browser build unsuccessful.');
+    process.exit(1);
+  }
+  console.log(stats.toString());
+  console.log('Browser build successful.');
+  process.exit(0);
+});
diff --git a/package.json b/package.json
index 0e59ddfd134..b9a54c59c13 100644
--- a/package.json
+++ b/package.json
@@ -71,6 +71,8 @@
   },
   "scripts": {
     "lint": "eslint .",
+    "build-browser": "node build-browser.js",
+    "prepublishOnly": "npm run build-browser",
     "release": "git pull && git push origin master --tags && npm publish",
     "release-legacy": "git pull origin 4.x && git push origin 4.x --tags && npm publish --tag legacy",
     "test": "mocha --exit test/*.test.js test/**/*.test.js",
@@ -88,7 +90,7 @@
     "url": "git://github.com/Automattic/mongoose.git"
   },
   "homepage": "https://mongoosejs.com",
-  "browser": "./browser.js",
+  "browser": "./dist/browser.umd.js",
   "eslintConfig": {
     "extends": [
       "eslint:recommended"
diff --git a/test/files/sample.js b/test/files/sample.js
index c6394c6ebce..8328e6f27cf 100644
--- a/test/files/sample.js
+++ b/test/files/sample.js
@@ -1,5 +1,5 @@
 'use strict';
-import mongoose from '../../browser.js';
+import mongoose from './dist/browser.umd.js';
 
 const doc = new mongoose.Document({}, new mongoose.Schema({
   name: String
diff --git a/test/webpack.test.js b/test/webpack.test.js
index 6ea6b61e7ee..0ff909433f0 100644
--- a/test/webpack.test.js
+++ b/test/webpack.test.js
@@ -16,58 +16,49 @@ describe('webpack', function() {
       this.skip();
     }
     const webpack = require('webpack');
-    this.timeout(45000);
+    this.timeout(90000);
     // acquit:ignore:end
-    const config = {
-      entry: ['./test/files/sample.js'],
-      // acquit:ignore:start
-      output: {
-        path: `${__dirname}/files`
-      },
-      // acquit:ignore:end
-      module: {
-        rules: [
-          {
-            test: /\.js$/,
-            include: [
-              /\/mongoose\//i,
-              /\/kareem\//i
-            ],
-            loader: 'babel-loader',
-            options: {
-              presets: ['es2015']
-            }
-          }
-        ]
-      },
-      node: {
-        // Replace these Node.js native modules with empty objects, Mongoose's
-        // browser library does not use them.
-        // See https://webpack.js.org/configuration/node/
-        dns: 'empty',
-        fs: 'empty',
-        'module': 'empty',
-        net: 'empty',
-        tls: 'empty'
-      },
-      target: 'web',
-      mode: 'production'
-    };
-    // acquit:ignore:start
-    webpack(config, utils.tick(function(error, stats) {
-      assert.ifError(error);
-      assert.deepEqual(stats.compilation.errors, []);
+    const webpackBundle = require('../webpack.config.js');
+    const webpackBundleForTest = Object.assign({}, webpackBundle, {
+      output: Object.assign({}, webpackBundle.output, { path: `${__dirname}/files` })
+    });
+    webpack(webpackBundleForTest, utils.tick(function(bundleBuildError, bundleBuildStats) {
+      assert.ifError(bundleBuildError);
+      assert.deepEqual(bundleBuildStats.compilation.errors, []);
 
       // Avoid expressions in `require()` because that scares webpack (gh-6705)
-      assert.ok(!stats.compilation.warnings.
+      assert.ok(!bundleBuildStats.compilation.warnings.
         find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
 
-      const content = fs.readFileSync(`${__dirname}/files/main.js`, 'utf8');
+      const bundleContent = fs.readFileSync(`${__dirname}/files/dist/browser.umd.js`, 'utf8');
+
+      acorn.parse(bundleContent, { ecmaVersion: 5 });
+
+      const baseConfig = require('../webpack.base.config.js');
+      const config = Object.assign({}, baseConfig, {
+        entry: ['./test/files/sample.js'],
+        // acquit:ignore:start
+        output: {
+          path: `${__dirname}/files`
+        },
+        // acquit:ignore:end
+      });
+      // acquit:ignore:start
+      webpack(config, utils.tick(function(error, stats) {
+        assert.ifError(error);
+        assert.deepEqual(stats.compilation.errors, []);
+
+        // Avoid expressions in `require()` because that scares webpack (gh-6705)
+        assert.ok(!stats.compilation.warnings.
+          find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
+
+        const content = fs.readFileSync(`${__dirname}/files/main.js`, 'utf8');
 
-      acorn.parse(content, { ecmaVersion: 5 });
+        acorn.parse(content, { ecmaVersion: 5 });
 
-      done();
+        done();
+      }));
+      // acquit:ignore:end
     }));
-    // acquit:ignore:end
   });
 });
diff --git a/webpack.base.config.js b/webpack.base.config.js
new file mode 100644
index 00000000000..c7286bece6a
--- /dev/null
+++ b/webpack.base.config.js
@@ -0,0 +1,33 @@
+'use strict';
+
+module.exports = {
+  module: {
+    rules: [
+      {
+        test: /\.js$/,
+        include: [
+          /\/mongoose\//i,
+          /\/kareem\//i,
+        ],
+        loader: 'babel-loader',
+        options: {
+          presets: ['es2015']
+        }
+      }
+    ]
+  },
+  node: {
+    // Replace these Node.js native modules with empty objects, Mongoose's
+    // browser library does not use them.
+    // See https://webpack.js.org/configuration/node/
+    dns: 'empty',
+    fs: 'empty',
+    module: 'empty',
+    net: 'empty',
+    tls: 'empty',
+  },
+  target: 'web',
+  mode: 'production',
+};
+
+
diff --git a/webpack.config.js b/webpack.config.js
new file mode 100644
index 00000000000..ce1faa8b343
--- /dev/null
+++ b/webpack.config.js
@@ -0,0 +1,24 @@
+'use strict';
+
+const paths = require('path');
+
+const base = require('./webpack.base.config.js');
+
+const webpackConfig = Object.assign({}, base, {
+  entry: require.resolve('./browser.js'),
+  output: {
+    filename: './dist/browser.umd.js',
+    path: paths.resolve(__dirname, ''),
+    library: 'mongoose',
+    libraryTarget: 'umd',
+    // override default 'window' globalObject so browser build will work in SSR environments
+    // may become unnecessary in webpack 5
+    globalObject: 'typeof self !== \'undefined\' ? self : this',
+  },
+  externals: [
+    /^node_modules\/.+$/
+  ],
+});
+
+module.exports = webpackConfig;
+

From f5b03570a002eb0b4f09601468cce3a1ded6e942 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 Nov 2019 18:55:11 -0500
Subject: [PATCH 0179/2348] fix: add SchemaMapOptions class for options to map
 schematype

Fix #8318
---
 lib/options/SchemaMapOptions.js | 43 +++++++++++++++++++++++++++++++++
 lib/schema/map.js               |  3 +++
 test/types.map.test.js          |  3 +++
 3 files changed, 49 insertions(+)
 create mode 100644 lib/options/SchemaMapOptions.js

diff --git a/lib/options/SchemaMapOptions.js b/lib/options/SchemaMapOptions.js
new file mode 100644
index 00000000000..c3691ac2b0d
--- /dev/null
+++ b/lib/options/SchemaMapOptions.js
@@ -0,0 +1,43 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+/**
+ * The options defined on a Map schematype.
+ *
+ * ####Example:
+ *
+ *     const schema = new Schema({ socialMediaHandles: { type: Map, of: String } });
+ *     schema.path('socialMediaHandles').options; // SchemaMapOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaMapOptions
+ */
+
+class SchemaMapOptions extends SchemaTypeOptions {}
+
+const opts = require('./propertyOptions');
+
+/**
+ * If set, specifies the type of this map's values. Mongoose will cast
+ * this map's values to the given type.
+ * 
+ * If not set, Mongoose will not cast the map's values.
+ * 
+ * ####Example:
+ *
+ *     // Mongoose will cast `socialMediaHandles` values to strings
+ *     const schema = new Schema({ socialMediaHandles: { type: Map, of: String } });
+ *     schema.path('socialMediaHandles').options.of; // String
+ *
+ * @api public
+ * @property of
+ * @memberOf SchemaMapOptions
+ * @type Function|string
+ * @instance
+ */
+
+Object.defineProperty(SchemaMapOptions.prototype, 'of', opts);
+
+module.exports = SchemaMapOptions;
\ No newline at end of file
diff --git a/lib/schema/map.js b/lib/schema/map.js
index a41481d5138..b6f7feeafdb 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -5,6 +5,7 @@
  */
 
 const MongooseMap = require('../types/map');
+const SchemaMapOptions = require('../options/SchemaMapOptions');
 const SchemaType = require('../schematype');
 
 /*!
@@ -42,4 +43,6 @@ class Map extends SchemaType {
   }
 }
 
+Map.prototype.OptionsConstructor = SchemaMapOptions;
+
 module.exports = Map;
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 5b3c2121e39..df99d479a5e 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -6,6 +6,7 @@
 
 const start = require('./common');
 
+const SchemaMapOptions = require('../lib/options/SchemaMapOptions');
 const assert = require('assert');
 const co = require('co');
 
@@ -47,6 +48,8 @@ describe('Map', function() {
       }
     });
 
+    assert.ok(TestSchema.path('v').options instanceof SchemaMapOptions);
+
     const Test = db.model('MapTest', TestSchema);
 
     return co(function*() {

From 5a1dbd8ec22e2f0a22af90144feb23b61538885b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 Nov 2019 18:58:30 -0500
Subject: [PATCH 0180/2348] style: fix lint

---
 lib/options/SchemaMapOptions.js | 4 ++--
 lib/schema.js                   | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/options/SchemaMapOptions.js b/lib/options/SchemaMapOptions.js
index c3691ac2b0d..335d84a9876 100644
--- a/lib/options/SchemaMapOptions.js
+++ b/lib/options/SchemaMapOptions.js
@@ -22,9 +22,9 @@ const opts = require('./propertyOptions');
 /**
  * If set, specifies the type of this map's values. Mongoose will cast
  * this map's values to the given type.
- * 
+ *
  * If not set, Mongoose will not cast the map's values.
- * 
+ *
  * ####Example:
  *
  *     // Mongoose will cast `socialMediaHandles` values to strings
diff --git a/lib/schema.js b/lib/schema.js
index 014b34479e6..2cbfe7da9b7 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -241,7 +241,7 @@ Schema.prototype.obj;
  * ####Example:
  *     const schema = new Schema({ name: String }, { _id: false });
  *     schema.paths; // { name: SchemaString { ... } }
- * 
+ *
  *     schema.add({ age: Number });
  *     schema.paths; // { name: SchemaString { ... }, age: SchemaNumber { ... } }
  *

From 203450c25244ef446625d3291982e002a3902e4f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 17 Nov 2019 09:25:33 -0500
Subject: [PATCH 0181/2348] test(documentarray): repro #8317

---
 test/types.documentarray.test.js | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index e367250c062..1a148714750 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -546,7 +546,7 @@ describe('types.documentarray', function() {
     });
 
     it('clears listeners on cast error (gh-6723)', function() {
-      const nested = new Schema({v: {type: Number}});
+      const nested = new Schema({ v: Number });
       const schema = new Schema({
         docs: [nested]
       });
@@ -559,6 +559,22 @@ describe('types.documentarray', function() {
 
       return m.save();
     });
+
+    it('slice() copies parent and path (gh-8317)', function() {
+      const nested = new Schema({ v: Number });
+      const schema = new Schema({
+        docs: [nested]
+      });
+      const M = db.model('gh8317', schema);
+
+      const doc = M.hydrate({ docs: [{ v: 1 }, { v: 2 }]});
+      let arr = doc.docs;
+      arr = arr.slice();
+      arr.splice(0, 1);
+
+      assert.equal(arr.length, 1);
+      assert.equal(doc.docs.length, 2);
+    });
   });
 
   it('cleans modified subpaths on splice() (gh-7249)', function() {

From a3b4ea17ddf2e740d54f3d677fce4f777a80df47 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 17 Nov 2019 09:25:49 -0500
Subject: [PATCH 0182/2348] fix(documentarray): fix error when modifying array
 after `slice()`

Fix #8317
---
 lib/types/documentarray.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index cc6f5d6d77f..87757e4f171 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -172,6 +172,14 @@ class CoreDocumentArray extends CoreMongooseArray {
     }));
   }
 
+  slice() {
+    const arr = super.slice.apply(this, arguments);
+    arr[arrayParentSymbol] = this[arrayParentSymbol];
+    arr[arrayPathSymbol] = this[arrayPathSymbol];
+
+    return arr;
+  }
+
   /**
    * Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking.
    *

From 3e9faef7e310383a02a2ec1433c8151c917ed425 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 17 Nov 2019 10:21:56 -0500
Subject: [PATCH 0183/2348] fix: add `mongoose.isValidObjectId()` function to
 test whether Mongoose can cast a value to an objectid

Fix #3823
---
 lib/index.js       | 45 +++++++++++++++++++++++++++++++++++++++++++++
 test/index.test.js |  6 ++++++
 2 files changed, 51 insertions(+)

diff --git a/lib/index.js b/lib/index.js
index 6fbfb932e5c..6edd382ae80 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -933,6 +933,51 @@ Mongoose.prototype.DocumentProvider = require('./document_provider');
 
 Mongoose.prototype.ObjectId = SchemaTypes.ObjectId;
 
+/**
+ * Returns true if Mongoose can cast the given value to an ObjectId, or
+ * false otherwise.
+ *
+ * ####Example:
+ *
+ *     mongoose.isValidObjectId(new mongoose.Types.ObjectId()); // true
+ *     mongoose.isValidObjectId('0123456789ab'); // true
+ *     mongoose.isValidObjectId(6); // false
+ *
+ * @method isValidObjectId
+ * @api public
+ */
+
+Mongoose.prototype.isValidObjectId = function(v) {
+  if (v == null) {
+    return true;
+  }
+  const base = this || mongoose;
+  const ObjectId = base.driver.get().ObjectId;
+  if (v instanceof ObjectId) {
+    return true;
+  }
+
+  if (v._id != null) {
+    if (v._id instanceof ObjectId) {
+      return true;
+    }
+    if (v._id.toString instanceof Function) {
+      v = v._id.toString();
+      return typeof v === 'string' && (v.length === 12 || v.length === 24);
+    }
+  }
+
+  if (v.toString instanceof Function) {
+    v = v.toString();
+  }
+
+  if (typeof v === 'string' && (v.length === 12 || v.length === 24)) {
+    return true;
+  }
+
+  return false;
+};
+
 /**
  * The Mongoose Decimal128 [SchemaType](/docs/schematypes.html). Used for
  * declaring paths in your schema that should be
diff --git a/test/index.test.js b/test/index.test.js
index 5e3c643cd4f..e24407979a8 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -712,6 +712,12 @@ describe('mongoose module:', function() {
     });
   });
 
+  it('isValidObjectId (gh-3823)', function() {
+    assert.ok(mongoose.isValidObjectId('0123456789ab'));
+    assert.ok(mongoose.isValidObjectId(new mongoose.Types.ObjectId()));
+    assert.ok(!mongoose.isValidObjectId(6));
+  });
+
   describe('exports', function() {
     function test(mongoose) {
       assert.equal(typeof mongoose.version, 'string');

From 6ea62ddd37eb981a83cda77399af11c4d3663077 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 17 Nov 2019 22:25:47 +0200
Subject: [PATCH 0184/2348] Reproduce #8317

---
 test/types.documentarray.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 1a148714750..4b31ee82cce 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -575,6 +575,20 @@ describe('types.documentarray', function() {
       assert.equal(arr.length, 1);
       assert.equal(doc.docs.length, 2);
     });
+
+    it('map() copies parent and path ()', function() {
+      const personSchema = new Schema({ friends: [{ name: { type: String } }]});
+      const Person = mongoose.model('Person', personSchema);
+
+      const person = new Person({ friends: [{ name: 'Hafez' }] });
+
+      const friendsNames = person.friends.map(friend => friend.name);
+
+      friendsNames.push('Sam');
+
+      assert.equal(friendsNames.length, 2);
+      assert.equal(friendsNames[1], 'Sam');
+    });
   });
 
   it('cleans modified subpaths on splice() (gh-7249)', function() {

From 7bd3663f61460e0c2e2b6854ddcf9d8be72f6028 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 17 Nov 2019 22:26:09 +0200
Subject: [PATCH 0185/2348] Fixes #8317 map(...)

---
 lib/types/documentarray.js | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 87757e4f171..9ac61bf69fd 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -180,6 +180,15 @@ class CoreDocumentArray extends CoreMongooseArray {
     return arr;
   }
 
+  map() {
+    const arr = super.map.apply(this,arguments);
+
+    arr[arrayParentSymbol] = this[arrayParentSymbol];
+    arr[arrayPathSymbol] = this[arrayPathSymbol];
+
+    return arr;
+  }
+
   /**
    * Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking.
    *
@@ -328,18 +337,18 @@ if (util.inspect.custom) {
 
 function _updateParentPopulated(arr) {
   const parent = arr[arrayParentSymbol];
-  if (parent.$__.populated != null) {
-    const populatedPaths = Object.keys(parent.$__.populated).
-      filter(p => p.startsWith(arr[arrayPathSymbol] + '.'));
+  if (parent.$__.populated == null) return;
 
-    for (const path of populatedPaths) {
-      const remnant = path.slice((arr[arrayPathSymbol] + '.').length);
-      if (!Array.isArray(parent.$__.populated[path].value)) {
-        continue;
-      }
+  const populatedPaths = Object.keys(parent.$__.populated).
+    filter(p => p.startsWith(arr[arrayPathSymbol] + '.'));
 
-      parent.$__.populated[path].value = arr.map(val => val.populated(remnant));
+  for (const path of populatedPaths) {
+    const remnant = path.slice((arr[arrayPathSymbol] + '.').length);
+    if (!Array.isArray(parent.$__.populated[path].value)) {
+      continue;
     }
+
+    parent.$__.populated[path].value = arr.map(val => val.populated(remnant));
   }
 }
 

From e01c247537ecb179e804c5692aa476fa0f13ed9a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 17 Nov 2019 22:33:06 +0200
Subject: [PATCH 0186/2348] Fix overwriting model name

---
 test/types.documentarray.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 4b31ee82cce..3150bdf8aba 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -578,7 +578,7 @@ describe('types.documentarray', function() {
 
     it('map() copies parent and path ()', function() {
       const personSchema = new Schema({ friends: [{ name: { type: String } }]});
-      const Person = mongoose.model('Person', personSchema);
+      const Person = mongoose.model('gh8317-map', personSchema);
 
       const person = new Person({ friends: [{ name: 'Hafez' }] });
 

From 7b719cdfc14ad9125dd41c240f9aa32315975f55 Mon Sep 17 00:00:00 2001
From: Zach Azar <azar@buildingconnected.com>
Date: Mon, 18 Nov 2019 10:26:38 -0800
Subject: [PATCH 0187/2348] Use default db if provided in connection string

---
 lib/connection.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index a8e418f49a9..edb573a5713 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -605,7 +605,13 @@ Connection.prototype.openUri = function(uri, options, callback) {
       if (err) {
         return reject(err);
       }
-      this.name = dbName != null ? dbName : get(parsed, 'auth.db', null);
+      if (dbName) {
+        this.name = dbName;
+      } else if (parsed.defaultDatabase) {
+        this.name = parsed.defaultDatabase;
+      } else {
+        this.name = get(parsed, 'auth.db', null);
+      }
       this.host = get(parsed, 'hosts.0.host', 'localhost');
       this.port = get(parsed, 'hosts.0.port', 27017);
       this.user = this.user || get(parsed, 'auth.username');

From 09e076631c2f7e3d2c1f5643e2f67bc0fb4be5fc Mon Sep 17 00:00:00 2001
From: Zach Azar <azar@buildingconnected.com>
Date: Mon, 18 Nov 2019 10:29:30 -0800
Subject: [PATCH 0188/2348] Add test for default db in uri

---
 test/connection.test.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index 16b05ac3305..b8cf36d5413 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -744,6 +744,13 @@ describe('connections:', function() {
     });
   });
 
+  it('uses default database in uri if options.dbName is not provided', function() {
+    return mongoose.createConnection('mongodb://localhost:27017/default-db-name').then(db => {
+      assert.equal(db.name, 'default-db-name');
+      db.close();
+    });
+  });
+
   it('startSession() (gh-6653)', function() {
     const conn = mongoose.createConnection('mongodb://localhost:27017/test');
 

From 8155c499d4a202451aa8cddf52f9079b781df4dc Mon Sep 17 00:00:00 2001
From: Zach Azar <azar@buildingconnected.com>
Date: Mon, 18 Nov 2019 10:32:57 -0800
Subject: [PATCH 0189/2348] Change docs for dbName so that it's not as strict

---
 docs/connections.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 7a4e6bd7e97..4246f7e967e 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -134,7 +134,7 @@ block content
     * `bufferCommands`    - This is a mongoose-specific option (not passed to the MongoDB driver) that disables [mongoose's buffering mechanism](http://mongoosejs.com/docs/faq.html#callback_never_executes)
     * `user`/`pass`       - The username and password for authentication. These options are mongoose-specific, they are equivalent to the MongoDB driver's `auth.user` and `auth.password` options.
     * `autoIndex`         - By default, mongoose will automatically build indexes defined in your schema when it connects. This is great for development, but not ideal for large production deployments, because index builds can cause performance degradation. If you set `autoIndex` to false, mongoose will not automatically build indexes for **any** model associated with this connection.
-    * `dbName`            - Specifies which database to connect to and overrides any database specified in the connection string. If you're using the `mongodb+srv` syntax to connect to [MongoDB Atlas](https://www.mongodb.com/cloud/atlas), you [should use `dbName` to specify the database](https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626) because you currently cannot in the connection string.
+    * `dbName`            - Specifies which database to connect to and overrides any database specified in the connection string. This is useful if you are unable to specify a default database in the connection string like with [some `mongodb+srv` syntax connections](https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626).
 
     Below are some of the options that are important for tuning mongoose.
 

From 4c150e08d2b6473a0322cc9055d65496f72001fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Nov 2019 13:08:44 -0800
Subject: [PATCH 0190/2348] test(model): repro #8343

---
 test/model.indexes.test.js | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 113980002cd..290fd59d8fe 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -104,12 +104,15 @@ describe('model', function() {
       });
     });
 
-    it('of embedded documents unless excludeIndexes (gh-5575)', function(done) {
-      const BlogPost = new Schema({
-        _id: {type: ObjectId},
-        title: {type: String, index: true},
+    it('of embedded documents unless excludeIndexes (gh-5575) (gh-8343)', function(done) {
+      const BlogPost = Schema({
+        _id: { type: ObjectId },
+        title: { type: String, index: true },
         desc: String
       });
+      const otherSchema = Schema({
+        name: { type: String, index: true }
+      }, { excludeIndexes: true })
 
       const User = new Schema({
         name: {type: String, index: true},
@@ -121,7 +124,8 @@ describe('model', function() {
         blogpost: {
           type: BlogPost,
           excludeIndexes: true
-        }
+        },
+        otherArr: [otherSchema]
       });
 
       const UserModel = db.model('gh5575', User);

From 0bc3455992ca2b395d7b14232a48ce0d8da2b7fe Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Nov 2019 13:09:11 -0800
Subject: [PATCH 0191/2348] fix(model): support setting `excludeIndexes` as
 schema option for subdocs

Fix #8343
---
 lib/helpers/schema/getIndexes.js          |  3 +-
 lib/options/SchemaDocumentArrayOptions.js | 48 +++++++++++++++++++++++
 lib/schema.js                             |  3 ++
 3 files changed, 53 insertions(+), 1 deletion(-)
 create mode 100644 lib/options/SchemaDocumentArrayOptions.js

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index 899d309b5ed..877156a2878 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -36,7 +36,8 @@ module.exports = function getIndexes(schema) {
 
       if (path.$isMongooseDocumentArray || path.$isSingleNested) {
         if (get(path, 'options.excludeIndexes') !== true &&
-            get(path, 'schemaOptions.excludeIndexes') !== true) {
+            get(path, 'schemaOptions.excludeIndexes') !== true &&
+            get(path, 'schema.options.excludeIndexes') !== true) {
           collectIndexes(path.schema, prefix + key + '.');
         }
 
diff --git a/lib/options/SchemaDocumentArrayOptions.js b/lib/options/SchemaDocumentArrayOptions.js
new file mode 100644
index 00000000000..0a17a87e5e4
--- /dev/null
+++ b/lib/options/SchemaDocumentArrayOptions.js
@@ -0,0 +1,48 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+/**
+ * The options defined on an Document Array schematype.
+ *
+ * ####Example:
+ *
+ *     const schema = new Schema({ users: [{ name: string }] });
+ *     schema.path('users').options; // SchemaDocumentArrayOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaDocumentOptions
+ */
+
+class SchemaDocumentArrayOptions extends SchemaTypeOptions {}
+
+const opts = require('./propertyOptions');
+
+/**
+ * If `true`, Mongoose will skip building any indexes defined in this array's schema.
+ * If not set, Mongoose will build all indexes defined in this array's schema.
+ * 
+ * ####Example:
+ * 
+ *     const childSchema = Schema({ name: { type: String, index: true } });
+ *     // If `excludeIndexes` is `true`, Mongoose will skip building an index
+ *     // on `arr.name`. Otherwise, Mongoose will build an index on `arr.name`.
+ *     const parentSchema = Schema({
+ *       arr: { type: [childSchema], excludeIndexes: true }
+ *     });
+ *
+ * @api public
+ * @property excludeIndexes
+ * @memberOf SchemaDocumentArrayOptions
+ * @type Array
+ * @instance
+ */
+
+Object.defineProperty(SchemaDocumentArrayOptions.prototype, 'excludeIndexes', opts);
+
+/*!
+ * ignore
+ */
+
+module.exports = SchemaArrayOptions;
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index 2cbfe7da9b7..1aac5594522 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -72,6 +72,9 @@ let id = 0;
  * - [timestamps](/docs/guide.html#timestamps): object or boolean - defaults to `false`. If true, Mongoose adds `createdAt` and `updatedAt` properties to your schema and manages those properties for you.
  * - [storeSubdocValidationError](/docs/guide.html#storeSubdocValidationError): boolean - Defaults to true. If false, Mongoose will wrap validation errors in single nested document subpaths into a single validation error on the single nested subdoc's path.
  *
+ * ####Options for Nested Schemas:
+ * - `excludeIndexes`: bool - defaults to `false`. If `true`, skip building indexes on this schema's paths.
+ *
  * ####Note:
  *
  * _When nesting schemas, (`children` in the example above), always declare the child schema first before passing it into its parent._

From 2881ddab8405adade0437e4dc42b7dfc7e3f170c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Nov 2019 13:16:34 -0800
Subject: [PATCH 0192/2348] fix: clean up some leftover issues with #8343

---
 lib/options/SchemaDocumentArrayOptions.js | 6 +++---
 lib/schema/documentarray.js               | 3 +++
 test/model.indexes.test.js                | 2 +-
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/options/SchemaDocumentArrayOptions.js b/lib/options/SchemaDocumentArrayOptions.js
index 0a17a87e5e4..2283616388c 100644
--- a/lib/options/SchemaDocumentArrayOptions.js
+++ b/lib/options/SchemaDocumentArrayOptions.js
@@ -22,9 +22,9 @@ const opts = require('./propertyOptions');
 /**
  * If `true`, Mongoose will skip building any indexes defined in this array's schema.
  * If not set, Mongoose will build all indexes defined in this array's schema.
- * 
+ *
  * ####Example:
- * 
+ *
  *     const childSchema = Schema({ name: { type: String, index: true } });
  *     // If `excludeIndexes` is `true`, Mongoose will skip building an index
  *     // on `arr.name`. Otherwise, Mongoose will build an index on `arr.name`.
@@ -45,4 +45,4 @@ Object.defineProperty(SchemaDocumentArrayOptions.prototype, 'excludeIndexes', op
  * ignore
  */
 
-module.exports = SchemaArrayOptions;
\ No newline at end of file
+module.exports = SchemaDocumentArrayOptions;
\ No newline at end of file
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 9d95f2727a4..c7c179e830b 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -7,6 +7,8 @@
 const ArrayType = require('./array');
 const CastError = require('../error/cast');
 const EventEmitter = require('events').EventEmitter;
+const SchemaDocumentArrayOptions =
+  require('../options/SchemaDocumentArrayOptions');
 const SchemaType = require('../schematype');
 const discriminator = require('../helpers/model/discriminator');
 const get = require('../helpers/get');
@@ -91,6 +93,7 @@ DocumentArrayPath.options = { castNonArrays: true };
  */
 DocumentArrayPath.prototype = Object.create(ArrayType.prototype);
 DocumentArrayPath.prototype.constructor = DocumentArrayPath;
+DocumentArrayPath.prototype.OptionsConstructor = SchemaDocumentArrayOptions;
 
 /*!
  * Ignore
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 290fd59d8fe..366953d50de 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -112,7 +112,7 @@ describe('model', function() {
       });
       const otherSchema = Schema({
         name: { type: String, index: true }
-      }, { excludeIndexes: true })
+      }, { excludeIndexes: true });
 
       const User = new Schema({
         name: {type: String, index: true},

From ba2c35377d5f48eca2d338eb10ab66de68ec237c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 Nov 2019 00:18:27 +0200
Subject: [PATCH 0193/2348] Make DocumentArray#map return a regular JS array

---
 lib/types/documentarray.js       | 8 ++------
 test/types.documentarray.test.js | 3 ++-
 2 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 9ac61bf69fd..89709f2fbda 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -181,11 +181,7 @@ class CoreDocumentArray extends CoreMongooseArray {
   }
 
   map() {
-    const arr = super.map.apply(this,arguments);
-
-    arr[arrayParentSymbol] = this[arrayParentSymbol];
-    arr[arrayPathSymbol] = this[arrayPathSymbol];
-
+    const arr = [].concat(Array.prototype.map.apply(this,arguments));
     return arr;
   }
 
@@ -337,7 +333,7 @@ if (util.inspect.custom) {
 
 function _updateParentPopulated(arr) {
   const parent = arr[arrayParentSymbol];
-  if (parent.$__.populated == null) return;
+  if (!parent || parent.$__.populated == null) return;
 
   const populatedPaths = Object.keys(parent.$__.populated).
     filter(p => p.startsWith(arr[arrayPathSymbol] + '.'));
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 3150bdf8aba..28a8d5f3ac6 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -576,13 +576,14 @@ describe('types.documentarray', function() {
       assert.equal(doc.docs.length, 2);
     });
 
-    it('map() copies parent and path ()', function() {
+    it('map() works and does not return a mongoose array', function() {
       const personSchema = new Schema({ friends: [{ name: { type: String } }]});
       const Person = mongoose.model('gh8317-map', personSchema);
 
       const person = new Person({ friends: [{ name: 'Hafez' }] });
 
       const friendsNames = person.friends.map(friend => friend.name);
+      assert.deepEqual(friendsNames.constructor, Array);
 
       friendsNames.push('Sam');
 

From ba38d1de8ec94d72d2730d6186fc01301f2258ea Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 Nov 2019 00:33:19 +0200
Subject: [PATCH 0194/2348] Add test to fiter

---
 test/types.documentarray.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 28a8d5f3ac6..33a60fd948a 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -590,6 +590,25 @@ describe('types.documentarray', function() {
       assert.equal(friendsNames.length, 2);
       assert.equal(friendsNames[1], 'Sam');
     });
+
+    it('filter() copies parent and path (gh-8317)', function() {
+      const personSchema = new Schema({ friends: [{ name: { type: String }, age: { type: Number } }] });
+      const Person = mongoose.model('gh8317-filter', personSchema);
+
+      const person = new Person({ friends: [
+        { name: 'Hafez', age: 25 },
+        { name: 'Sam', age: 27 }
+      ] });
+
+      const filteredFriends = person.friends.filter(friend => friend.age > 26);
+      assert.ok(filteredFriends.isMongooseArray);
+      assert.equal(filteredFriends.constructor.name, 'CoreDocumentArray');
+
+      filteredFriends.push({ name: 'John', age: 30 });
+
+      assert.equal(filteredFriends.length, 2);
+      assert.equal(filteredFriends[1].name, 'John');
+    });
   });
 
   it('cleans modified subpaths on splice() (gh-7249)', function() {

From a32d9a823f9da8d8067c2a4ce8848cf6f0abd833 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Nov 2019 16:41:12 -0800
Subject: [PATCH 0195/2348] test(populate): repro #8324

---
 test/model.populate.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 8abdabb8a2c..adc08ac92a2 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8801,5 +8801,33 @@ describe('model: populate:', function() {
         assert.equal(doc.troops[3].name, 'Card 4');
       });
     });
+
+    it('virtual populate with discriminator that has a custom discriminator value (gh-8324)', function() {
+      const mainSchema = new Schema({ title: { type: String } },
+        { discriminatorKey: 'type' });
+      
+      mainSchema.virtual('virtualField', {
+        ref: 'gh8324_Model',
+        localField: '_id',
+        foreignField: 'main',
+      });
+      
+      const discriminatedSchema = new Schema({ description: String });
+      const Main = db.model('gh8324_Main', mainSchema);
+      const Discriminator = Main.discriminator('gh8324_Discriminator',
+        discriminatedSchema, 'customValue');
+      const Model = db.model('gh8324_Model', Schema({
+        main: 'ObjectId'
+      }));
+
+      return co(function*() {
+        const d = yield Discriminator.create({ title: 'test', description: 'test' });
+        yield Model.create({ main: d._id });
+
+        const docs = yield Main.find().populate('virtualField').exec();
+        console.log(docs.map(d => d.virtualField))
+        assert.ok(docs[0].virtualField[0].main);
+      });
+    });
   });
 });

From ff3d36ffd13e5308dd52d54b0b970aa1e63a508d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Nov 2019 16:42:58 -0800
Subject: [PATCH 0196/2348] fix(populate+discriminator): handle populating
 document whose discriminator value is different from discriminator model name

Fix #8324
---
 lib/helpers/discriminator/getConstructor.js   |  2 +-
 .../discriminator/getDiscriminatorByValue.js  | 27 +++++++++++++++++
 .../populate/getModelsMapForPopulate.js       | 17 +++++++----
 lib/model.js                                  |  2 +-
 lib/query.js                                  |  3 +-
 lib/queryhelpers.js                           | 30 ++-----------------
 lib/schema/array.js                           |  2 +-
 lib/types/documentarray.js                    |  2 +-
 test/model.populate.test.js                   |  1 -
 9 files changed, 47 insertions(+), 39 deletions(-)
 create mode 100644 lib/helpers/discriminator/getDiscriminatorByValue.js

diff --git a/lib/helpers/discriminator/getConstructor.js b/lib/helpers/discriminator/getConstructor.js
index e5a12950fef..04a3dedd83a 100644
--- a/lib/helpers/discriminator/getConstructor.js
+++ b/lib/helpers/discriminator/getConstructor.js
@@ -1,6 +1,6 @@
 'use strict';
 
-const getDiscriminatorByValue = require('../../queryhelpers').getDiscriminatorByValue;
+const getDiscriminatorByValue = require('./getDiscriminatorByValue');
 
 /*!
  * Find the correct constructor, taking into account discriminators
diff --git a/lib/helpers/discriminator/getDiscriminatorByValue.js b/lib/helpers/discriminator/getDiscriminatorByValue.js
new file mode 100644
index 00000000000..334be1500d2
--- /dev/null
+++ b/lib/helpers/discriminator/getDiscriminatorByValue.js
@@ -0,0 +1,27 @@
+'use strict';
+
+/*!
+* returns discriminator by discriminatorMapping.value
+*
+* @param {Model} model
+* @param {string} value
+*/
+
+module.exports = function getDiscriminatorByValue(model, value) {
+ let discriminator = null;
+ if (!model.discriminators) {
+   return discriminator;
+ }
+ for (const name in model.discriminators) {
+   const it = model.discriminators[name];
+   if (
+     it.schema &&
+     it.schema.discriminatorMapping &&
+     it.schema.discriminatorMapping.value == value
+   ) {
+     discriminator = it;
+     break;
+   }
+ }
+ return discriminator;
+}
\ No newline at end of file
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 990f8a64c32..d2c3e449672 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -2,6 +2,7 @@
 
 const MongooseError = require('../../error/index');
 const get = require('../get');
+const getDiscriminatorByValue = require('../discriminator/getDiscriminatorByValue');
 const isPathExcluded = require('../projection/isPathExcluded');
 const getSchemaTypes = require('./getSchemaTypes');
 const getVirtual = require('./getVirtual');
@@ -297,12 +298,18 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
       if (!schema && discriminatorKey) {
         modelForFindSchema = utils.getValue(discriminatorKey, doc);
-
         if (modelForFindSchema) {
-          try {
-            modelForCurrentDoc = model.db.model(modelForFindSchema);
-          } catch (error) {
-            return error;
+          // `modelForFindSchema` is the discriminator value, so we might need
+          // find the discriminated model name
+          const discriminatorModel = getDiscriminatorByValue(model, modelForFindSchema);
+          if (discriminatorModel != null) {
+            modelForCurrentDoc = discriminatorModel;
+          } else {
+            try {
+              modelForCurrentDoc = model.db.model(modelForFindSchema);
+            } catch (error) {
+              return error;
+            }
           }
 
           schemaForCurrentDoc = modelForCurrentDoc.schema._getSchema(options.path);
diff --git a/lib/model.js b/lib/model.js
index ba982da837d..a48cecb3b27 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -30,7 +30,7 @@ const assignVals = require('./helpers/populate/assignVals');
 const castBulkWrite = require('./helpers/model/castBulkWrite');
 const discriminator = require('./helpers/model/discriminator');
 const each = require('./helpers/each');
-const getDiscriminatorByValue = require('./queryhelpers').getDiscriminatorByValue;
+const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const getModelsMapForPopulate = require('./helpers/populate/getModelsMapForPopulate');
 const immediate = require('./helpers/immediate');
 const internalToObjectOptions = require('./options').internalToObjectOptions;
diff --git a/lib/query.js b/lib/query.js
index 4a31e40d50f..bb501e5c5ae 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -18,6 +18,7 @@ const castArrayFilters = require('./helpers/update/castArrayFilters');
 const castUpdate = require('./helpers/query/castUpdate');
 const completeMany = require('./helpers/query/completeMany');
 const get = require('./helpers/get');
+const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const hasDollarKeys = require('./helpers/query/hasDollarKeys');
 const helpers = require('./queryhelpers');
 const isInclusive = require('./helpers/projection/isInclusive');
@@ -4429,7 +4430,7 @@ Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
       typeof filter[schema.options.discriminatorKey] !== 'object' &&
       schema.discriminators != null) {
     const discriminatorValue = filter[schema.options.discriminatorKey];
-    const byValue = helpers.getDiscriminatorByValue(this.model, discriminatorValue);
+    const byValue = getDiscriminatorByValue(this.model, discriminatorValue);
     schema = schema.discriminators[discriminatorValue] ||
       (byValue && byValue.schema) ||
       schema;
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 045354f0f84..fc1a5953093 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -7,6 +7,8 @@
 const checkEmbeddedDiscriminatorKeyProjection =
   require('./helpers/discriminator/checkEmbeddedDiscriminatorKeyProjection');
 const get = require('./helpers/get');
+const getDiscriminatorByValue =
+  require('./helpers/discriminator/getDiscriminatorByValue');
 const isDefiningProjection = require('./helpers/projection/isDefiningProjection');
 const utils = require('./utils');
 
@@ -71,34 +73,6 @@ exports.preparePopulationOptionsMQ = function preparePopulationOptionsMQ(query,
   return pop;
 };
 
-
-/*!
- * returns discriminator by discriminatorMapping.value
- *
- * @param {Model} model
- * @param {string} value
- */
-function getDiscriminatorByValue(model, value) {
-  let discriminator = null;
-  if (!model.discriminators) {
-    return discriminator;
-  }
-  for (const name in model.discriminators) {
-    const it = model.discriminators[name];
-    if (
-      it.schema &&
-      it.schema.discriminatorMapping &&
-      it.schema.discriminatorMapping.value == value
-    ) {
-      discriminator = it;
-      break;
-    }
-  }
-  return discriminator;
-}
-
-exports.getDiscriminatorByValue = getDiscriminatorByValue;
-
 /*!
  * If the document is a mapped discriminator type, it returns a model instance for that type, otherwise,
  * it returns an instance of the given model.
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 09547385374..ba1e5d475b7 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -17,7 +17,7 @@ const util = require('util');
 const utils = require('../utils');
 const castToNumber = require('./operators/helpers').castToNumber;
 const geospatial = require('./operators/geospatial');
-const getDiscriminatorByValue = require('../queryhelpers').getDiscriminatorByValue;
+const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminatorByValue');
 
 let MongooseArray;
 let EmbeddedDoc;
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 87757e4f171..8ffa7674a31 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -8,7 +8,7 @@ const CoreMongooseArray = require('./core_array');
 const Document = require('../document');
 const ObjectId = require('./objectid');
 const castObjectId = require('../cast/objectid');
-const getDiscriminatorByValue = require('../queryhelpers').getDiscriminatorByValue;
+const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminatorByValue');
 const internalToObjectOptions = require('../options').internalToObjectOptions;
 const util = require('util');
 const utils = require('../utils');
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index adc08ac92a2..f673dfff1b4 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8825,7 +8825,6 @@ describe('model: populate:', function() {
         yield Model.create({ main: d._id });
 
         const docs = yield Main.find().populate('virtualField').exec();
-        console.log(docs.map(d => d.virtualField))
         assert.ok(docs[0].virtualField[0].main);
       });
     });

From 757579d54c285ed438eedf664e1980e70e32658c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Nov 2019 17:03:16 -0800
Subject: [PATCH 0197/2348] fix(connection): only buffer for "open" events when
 calling connection helper while connecting

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index edb573a5713..0af78cccc8b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -420,7 +420,7 @@ function _wrapConnHelper(fn) {
       Array.prototype.slice.call(arguments, 0, arguments.length - 1) :
       Array.prototype.slice.call(arguments);
     return utils.promiseOrCallback(cb, cb => {
-      if (this.readyState !== STATES.connected) {
+      if (this.readyState === STATES.connecting) {
         this.once('open', function() {
           fn.apply(this, argsWithoutCb.concat([cb]));
         });

From ab194a05a2c5493c6f3d542edfacb78e7db7cd98 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Nov 2019 07:49:16 -0800
Subject: [PATCH 0198/2348] feat(model): add Model.cleanIndexes() to drop
 non-schema indexes

Fix #6676
---
 lib/model.js               | 85 +++++++++++++++++++++++---------------
 test/model.indexes.test.js | 27 ++++++++++++
 2 files changed, 79 insertions(+), 33 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 6f10c5f9ee1..25b71aa38b3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1316,7 +1316,47 @@ Model.createCollection = function createCollection(options, callback) {
 Model.syncIndexes = function syncIndexes(options, callback) {
   _checkContext(this, 'syncIndexes');
 
-  const dropNonSchemaIndexes = (cb) => {
+  callback = this.$handleCallbackError(callback);
+
+  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+    this.createCollection(err => {
+      if (err) {
+        return cb(err);
+      }
+      this.cleanIndexes((err, dropped) => {
+        if (err != null) {
+          return cb(err);
+        }
+        this.createIndexes(options, err => {
+          if (err != null) {
+            return cb(err);
+          }
+          cb(null, dropped);
+        });
+      });
+    });
+  }), this.events);
+};
+
+/**
+ * Deletes all indexes that aren't defined in this model's schema. Used by
+ * `syncIndexes()`.
+ * 
+ * The returned promise resolves to a list of the dropped indexes' names as an array
+ * 
+ * @param {Function} [callback] optional callback
+ * @return {Promise|undefined} Returns `undefined` if callback is specified, returns a promise if no callback.
+ * @api public
+ */
+
+Model.cleanIndexes = function cleanIndexes(callback) {
+  _checkContext(this, 'cleanIndexes');
+
+  callback = this.$handleCallbackError(callback);
+
+  return utils.promiseOrCallback(callback, cb => {
+    const collection = this.collection;
+
     this.listIndexes((err, indexes) => {
       if (err != null) {
         return cb(err);
@@ -1349,44 +1389,23 @@ Model.syncIndexes = function syncIndexes(options, callback) {
 
       dropIndexes(toDrop, cb);
     });
-  };
 
-  const dropIndexes = (toDrop, cb) => {
-    let remaining = toDrop.length;
-    let error = false;
-    toDrop.forEach(indexName => {
-      this.collection.dropIndex(indexName, err => {
-        if (err != null) {
-          error = true;
-          return cb(err);
-        }
-        if (!error) {
-          --remaining || cb(null, toDrop);
-        }
-      });
-    });
-  };
-
-  callback = this.$handleCallbackError(callback);
-
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
-    this.createCollection(err => {
-      if (err) {
-        return cb(err);
-      }
-      dropNonSchemaIndexes((err, dropped) => {
-        if (err != null) {
-          return cb(err);
-        }
-        this.createIndexes(options, err => {
+    function dropIndexes(toDrop, cb) {
+      let remaining = toDrop.length;
+      let error = false;
+      toDrop.forEach(indexName => {
+        collection.dropIndex(indexName, err => {
           if (err != null) {
+            error = true;
             return cb(err);
           }
-          cb(null, dropped);
+          if (!error) {
+            --remaining || cb(null, toDrop);
+          }
         });
       });
-    });
-  }), this.events);
+    }
+  });
 };
 
 /*!
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 113980002cd..e3ea476e119 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -7,6 +7,7 @@
 const start = require('./common');
 
 const assert = require('assert');
+const co = require('co');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
@@ -430,5 +431,31 @@ describe('model', function() {
         then(() => User.syncIndexes()).
         then(dropped => assert.equal(dropped.length, 0));
     });
+
+    it('cleanIndexes (gh-6676)', function() {
+      return co(function*() {
+        let M = db.model('gh6676', new Schema({
+          name: { type: String, index: true }
+        }, { autoIndex: false }), 'gh6676');
+
+        yield M.createIndexes();
+
+        let indexes = yield M.listIndexes();
+        assert.deepEqual(indexes.map(i => i.key), [
+          { _id: 1 },
+          { name: 1 }
+        ]);
+
+        M = db.model('gh6676_2', new Schema({
+          name: String
+        }, { autoIndex: false }), 'gh6676');
+
+        yield M.cleanIndexes();
+        indexes = yield M.listIndexes();
+        assert.deepEqual(indexes.map(i => i.key), [
+          { _id: 1 }
+        ]);
+      });
+    });
   });
 });

From 9509b47326c800d71b3e61c3d14b8c0525a3c627 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Nov 2019 07:51:20 -0800
Subject: [PATCH 0199/2348] style: fix lint

---
 .../discriminator/getDiscriminatorByValue.js  | 30 +++++++++----------
 test/model.populate.test.js                   |  4 +--
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/lib/helpers/discriminator/getDiscriminatorByValue.js b/lib/helpers/discriminator/getDiscriminatorByValue.js
index 334be1500d2..87b3ad9940a 100644
--- a/lib/helpers/discriminator/getDiscriminatorByValue.js
+++ b/lib/helpers/discriminator/getDiscriminatorByValue.js
@@ -8,20 +8,20 @@
 */
 
 module.exports = function getDiscriminatorByValue(model, value) {
- let discriminator = null;
- if (!model.discriminators) {
-   return discriminator;
- }
- for (const name in model.discriminators) {
-   const it = model.discriminators[name];
-   if (
-     it.schema &&
+  let discriminator = null;
+  if (!model.discriminators) {
+    return discriminator;
+  }
+  for (const name in model.discriminators) {
+    const it = model.discriminators[name];
+    if (
+      it.schema &&
      it.schema.discriminatorMapping &&
      it.schema.discriminatorMapping.value == value
-   ) {
-     discriminator = it;
-     break;
-   }
- }
- return discriminator;
-}
\ No newline at end of file
+    ) {
+      discriminator = it;
+      break;
+    }
+  }
+  return discriminator;
+};
\ No newline at end of file
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index f673dfff1b4..5877e3d2ca2 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8805,13 +8805,13 @@ describe('model: populate:', function() {
     it('virtual populate with discriminator that has a custom discriminator value (gh-8324)', function() {
       const mainSchema = new Schema({ title: { type: String } },
         { discriminatorKey: 'type' });
-      
+
       mainSchema.virtual('virtualField', {
         ref: 'gh8324_Model',
         localField: '_id',
         foreignField: 'main',
       });
-      
+
       const discriminatedSchema = new Schema({ description: String });
       const Main = db.model('gh8324_Main', mainSchema);
       const Discriminator = Main.discriminator('gh8324_Discriminator',

From 4599877d99b7c8f824acba6e520f4efdf8a1f616 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 Nov 2019 20:51:51 +0200
Subject: [PATCH 0200/2348] Revert making map return vanilla JS Array

---
 lib/types/documentarray.js       | 5 -----
 test/types.documentarray.test.js | 4 +---
 2 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 89709f2fbda..b9cc33cd24d 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -180,11 +180,6 @@ class CoreDocumentArray extends CoreMongooseArray {
     return arr;
   }
 
-  map() {
-    const arr = [].concat(Array.prototype.map.apply(this,arguments));
-    return arr;
-  }
-
   /**
    * Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking.
    *
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 33a60fd948a..ae92c672169 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -576,15 +576,13 @@ describe('types.documentarray', function() {
       assert.equal(doc.docs.length, 2);
     });
 
-    it('map() works and does not return a mongoose array', function() {
+    it('map() works', function() {
       const personSchema = new Schema({ friends: [{ name: { type: String } }]});
       const Person = mongoose.model('gh8317-map', personSchema);
 
       const person = new Person({ friends: [{ name: 'Hafez' }] });
 
       const friendsNames = person.friends.map(friend => friend.name);
-      assert.deepEqual(friendsNames.constructor, Array);
-
       friendsNames.push('Sam');
 
       assert.equal(friendsNames.length, 2);

From 63c2f1efe21f4a0f0615008440df212d7ceaf9fa Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 Nov 2019 21:19:19 +0200
Subject: [PATCH 0201/2348] Remove filter test

---
 test/types.documentarray.test.js | 19 -------------------
 1 file changed, 19 deletions(-)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index ae92c672169..8140ee484b0 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -588,25 +588,6 @@ describe('types.documentarray', function() {
       assert.equal(friendsNames.length, 2);
       assert.equal(friendsNames[1], 'Sam');
     });
-
-    it('filter() copies parent and path (gh-8317)', function() {
-      const personSchema = new Schema({ friends: [{ name: { type: String }, age: { type: Number } }] });
-      const Person = mongoose.model('gh8317-filter', personSchema);
-
-      const person = new Person({ friends: [
-        { name: 'Hafez', age: 25 },
-        { name: 'Sam', age: 27 }
-      ] });
-
-      const filteredFriends = person.friends.filter(friend => friend.age > 26);
-      assert.ok(filteredFriends.isMongooseArray);
-      assert.equal(filteredFriends.constructor.name, 'CoreDocumentArray');
-
-      filteredFriends.push({ name: 'John', age: 30 });
-
-      assert.equal(filteredFriends.length, 2);
-      assert.equal(filteredFriends[1].name, 'John');
-    });
   });
 
   it('cleans modified subpaths on splice() (gh-7249)', function() {

From 33412d91d044daade5a135c7f35f607591c75a09 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Nov 2019 15:13:29 -0800
Subject: [PATCH 0202/2348] chore: release 5.7.12

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 91ae6d36208..6110027d00b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.7.12 / 2019-11-19
+===================
+ * fix: avoid throwing error if calling `push()` on a doc array with no parent #8351 #8317 #8312 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(connection): only buffer for "open" events when calling connection helper while connecting #8319
+ * fix(connection): pull default database from connection string if specified #8355 #8354 [zachazar](https://github.com/zachazar)
+ * fix(populate+discriminator): handle populating document whose discriminator value is different from discriminator model name #8324
+ * fix: add `mongoose.isValidObjectId()` function to test whether Mongoose can cast a value to an objectid #3823
+ * fix(model): support setting `excludeIndexes` as schema option for subdocs #8343
+ * fix: add SchemaMapOptions class for options to map schematype #8318
+ * docs(query): remove duplicate omitUndefined options #8349 [mdumandag](https://github.com/mdumandag)
+ * docs(schema): add Schema#paths docs to public API docs #8340
+
 5.7.11 / 2019-11-14
 ===================
  * fix: update mongodb driver -> 3.3.4 #8276
diff --git a/package.json b/package.json
index aaa6e1eb422..1f18d556c8d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.12-pre",
+  "version": "5.7.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From ec7d7d1b9207c66e9935857ac710e12e4f0c6628 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Nov 2019 20:10:12 -0800
Subject: [PATCH 0203/2348] feat(schema): add `Schema#pick()` function to
 create a new schema with a picked subset of the original schema's paths

Fix #8207
---
 lib/model.js        |  4 +--
 lib/schema.js       | 44 ++++++++++++++++++++++++++
 test/schema.test.js | 77 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 123 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 86695ad84ca..bd548293190 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1341,9 +1341,9 @@ Model.syncIndexes = function syncIndexes(options, callback) {
 /**
  * Deletes all indexes that aren't defined in this model's schema. Used by
  * `syncIndexes()`.
- * 
+ *
  * The returned promise resolves to a list of the dropped indexes' names as an array
- * 
+ *
  * @param {Function} [callback] optional callback
  * @return {Promise|undefined} Returns `undefined` if callback is specified, returns a promise if no callback.
  * @api public
diff --git a/lib/schema.js b/lib/schema.js
index 1aac5594522..f2f04bc70f6 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -6,6 +6,7 @@
 
 const EventEmitter = require('events').EventEmitter;
 const Kareem = require('kareem');
+const MongooseError = require('./error/mongooseError');
 const SchemaType = require('./schematype');
 const SchemaTypeOptions = require('./options/SchemaTypeOptions');
 const VirtualType = require('./virtualtype');
@@ -332,6 +333,49 @@ Schema.prototype.clone = function() {
   return s;
 };
 
+/**
+ * Returns a new schema that has the picked `paths` from this schema.
+ *
+ * This method is analagous to [Lodash's `pick()` function](https://lodash.com/docs/4.17.15#pick) for Mongoose schemas.
+ *
+ * ####Example:
+ *
+ *     const schema = Schema({ name: String, age: Number });
+ *     // Creates a new schema with the same `name` path as `schema`,
+ *     // but no `age` path.
+ *     const newSchema = schema.pick(['name']);
+ *
+ *     newSchema.path('name'); // SchemaString { ... }
+ *     newSchema.path('age'); // undefined
+ *
+ * @param {Array} paths list of paths to pick
+ * @param {Object} [options] options to pass to the schema constructor. Defaults to `this.options` if not set.
+ * @return {Schema}
+ * @api public
+ */
+
+Schema.prototype.pick = function(paths, options) {
+  const newSchema = new Schema({}, options || this.options);
+  if (!Array.isArray(paths)) {
+    throw new MongooseError('Schema#pick() only accepts an array argument, ' +
+      'got "' + typeof paths + '"');
+  }
+
+  for (const path of paths) {
+    if (this.nested[path]) {
+      newSchema.add({ [path]: get(this.tree, path) });
+    } else {
+      const schematype = this.path(path);
+      if (schematype == null) {
+        throw new MongooseError('Path `' + path + '` is not in the schema');
+      }
+      newSchema.add({ [path]: schematype });
+    }
+  }
+
+  return newSchema;
+};
+
 /**
  * Returns default options for this schema, merged with `options`.
  *
diff --git a/test/schema.test.js b/test/schema.test.js
index 30ca6a7c59d..b8b1d1dab51 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1704,8 +1704,10 @@ describe('schema', function() {
     });
 
     it('removes a single path', function(done) {
+      assert.ok(this.schema.paths.a);
       this.schema.remove('a');
       assert.strictEqual(this.schema.path('a'), undefined);
+      assert.strictEqual(this.schema.paths.a, void 0);
       done();
     });
 
@@ -2168,4 +2170,79 @@ describe('schema', function() {
 
     assert.equal(newSchema.path('title').options.type, String);
   });
+
+  describe('pick() (gh-8207)', function() {
+    it('works with nested paths', function() {
+      const schema = Schema({
+        name: {
+          first: {
+            type: String,
+            required: true
+          },
+          last: {
+            type: String,
+            required: true
+          }
+        },
+        age: {
+          type: Number,
+          index: true
+        }
+      });
+      assert.ok(schema.path('name.first'));
+      assert.ok(schema.path('name.last'));
+
+      let newSchema = schema.pick(['age']);
+      assert.ok(!newSchema.path('name.first'));
+      assert.ok(newSchema.path('age'));
+      assert.ok(newSchema.path('age').index);
+
+      newSchema = schema.pick(['name']);
+      assert.ok(newSchema.path('name.first'));
+      assert.ok(newSchema.path('name.first').required);
+      assert.ok(newSchema.path('name.last'));
+      assert.ok(newSchema.path('name.last').required);
+      assert.ok(!newSchema.path('age'));
+
+      newSchema = schema.pick(['name.first']);
+      assert.ok(newSchema.path('name.first'));
+      assert.ok(newSchema.path('name.first').required);
+      assert.ok(!newSchema.path('name.last'));
+      assert.ok(!newSchema.path('age'));
+    });
+
+    it('with single nested paths', function() {
+      const schema = Schema({
+        name: Schema({
+          first: {
+            type: String,
+            required: true
+          },
+          last: {
+            type: String,
+            required: true
+          }
+        }),
+        age: {
+          type: Number,
+          index: true
+        }
+      });
+      assert.ok(schema.path('name.first'));
+      assert.ok(schema.path('name.last'));
+
+      let newSchema = schema.pick(['name']);
+      assert.ok(newSchema.path('name.first'));
+      assert.ok(newSchema.path('name.first').required);
+      assert.ok(newSchema.path('name.last'));
+      assert.ok(newSchema.path('name.last').required);
+      assert.ok(!newSchema.path('age'));
+
+      newSchema = schema.pick(['name.first']);
+      assert.ok(newSchema.path('name.first'));
+      assert.ok(newSchema.path('name.first').required);
+      assert.ok(!newSchema.path('name.last'));
+      assert.ok(!newSchema.path('age'));
+    });
+  });
 });

From c6f3dd2ed0843356beb53580c181eac6019d0d4e Mon Sep 17 00:00:00 2001
From: Fonger <5862369+Fonger@users.noreply.github.com>
Date: Wed, 20 Nov 2019 19:04:09 +0800
Subject: [PATCH 0204/2348] test(model): repro #8363

---
 test/model.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index fc6c2b40a20..7e84b5a0e50 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4909,6 +4909,18 @@ describe('Model', function() {
       });
     });
 
+    it('insertMany() with non object array error can be catched (gh-8363)', function(done) {
+      const schema = mongoose.Schema({
+        _id: mongoose.Schema.Types.ObjectId,
+        url: { type: String }
+      });
+      const Image = db.model('gh8363', schema);
+      Image.insertMany(['a', 'b', 'c']).catch((error) => {
+        assert.equal(error.name, 'ObjectParameterError');
+        done();
+      });
+    });
+
     it('insertMany() return docs with empty modifiedPaths (gh-7852)', function() {
       const schema = new Schema({
         name: { type: String }

From b5b21fbb4672e9cc64a6a0c194c894153daa4ee3 Mon Sep 17 00:00:00 2001
From: Fonger <5862369+Fonger@users.noreply.github.com>
Date: Wed, 20 Nov 2019 19:05:26 +0800
Subject: [PATCH 0205/2348] fix(model): catch error when insertMany fails to
 cast document

Fixes #8363
---
 lib/model.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index a48cecb3b27..f88c8f4edbb 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3206,10 +3206,15 @@ Model.$__insertMany = function(arr, options, callback) {
 
   const toExecute = [];
   const validationErrors = [];
+
   arr.forEach(function(doc) {
     toExecute.push(function(callback) {
       if (!(doc instanceof _this)) {
-        doc = new _this(doc);
+        try {
+          doc = new _this(doc);
+        } catch (err) {
+          return callback(err);
+        }
       }
       if (options.session != null) {
         doc.$session(options.session);

From b1daeb73cd3886ef567e1b8aa143ecf2b8e22c7b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 20 Nov 2019 07:23:04 -0800
Subject: [PATCH 0206/2348] docs(connection): document `Connection#models`
 property

Fix #8314
---
 lib/connection.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index 0af78cccc8b..2fbb4a67dae 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -187,6 +187,27 @@ Connection.prototype.collections;
 
 Connection.prototype.name;
 
+/**
+ * A [POJO](https://masteringjs.io/tutorials/fundamentals/pojo) containing
+ * a map from model names to models. Contains all models that have been
+ * added to this connection using [`Connection#model()`](/docs/api/connection.html#connection_Connection-model).
+ *
+ * ####Example
+ *
+ *     const conn = mongoose.createConnection();
+ *     const Test = conn.model('Test', mongoose.Schema({ name: String }));
+ *
+ *     Object.keys(conn.models).length; // 1
+ *     conn.models.Test === Test; // true
+ *
+ * @property models
+ * @memberOf Connection
+ * @instance
+ * @api public
+ */
+
+Connection.prototype.models;
+
 /**
  * The plugins that will be applied to all models created on this connection.
  *

From 40dbc06ed8281bbbb192686421c47a7f7e1f8a3c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 20 Nov 2019 07:23:32 -0800
Subject: [PATCH 0207/2348] chore: now working on 5.7.13

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 1f18d556c8d..b62f2f67abe 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.12",
+  "version": "5.7.13-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From cd7fd0197c65e833145bd7567ecaa8b27e83269b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 20 Nov 2019 15:38:32 -0800
Subject: [PATCH 0208/2348] feat(schema): support `enum` validator for number
 type

Fix #8139
---
 lib/error/messages.js              |  1 +
 lib/options/SchemaNumberOptions.js | 13 +++++++++
 lib/schema/number.js               | 46 ++++++++++++++++++++++++++++++
 test/document.test.js              | 23 +++++++++++++++
 4 files changed, 83 insertions(+)

diff --git a/lib/error/messages.js b/lib/error/messages.js
index 4483a86d7ab..78fb6d5dc7e 100644
--- a/lib/error/messages.js
+++ b/lib/error/messages.js
@@ -34,6 +34,7 @@ msg.general.required = 'Path `{PATH}` is required.';
 msg.Number = {};
 msg.Number.min = 'Path `{PATH}` ({VALUE}) is less than minimum allowed value ({MIN}).';
 msg.Number.max = 'Path `{PATH}` ({VALUE}) is more than maximum allowed value ({MAX}).';
+msg.Number.enum = '`{VALUE}` is not a valid enum value for path `{PATH}`.';
 
 msg.Date = {};
 msg.Date.min = 'Path `{PATH}` ({VALUE}) is before minimum allowed value ({MIN}).';
diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index e14e1cc9171..c9b4c709e82 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -45,6 +45,19 @@ Object.defineProperty(SchemaNumberOptions.prototype, 'min', opts);
 
 Object.defineProperty(SchemaNumberOptions.prototype, 'max', opts);
 
+/**
+ * If set, Mongoose adds a validator that checks that this path is strictly
+ * equal to one of the given values.
+ *
+ * @api public
+ * @property enum
+ * @memberOf SchemaNumberOptions
+ * @type Array
+ * @instance
+ */
+
+Object.defineProperty(SchemaNumberOptions.prototype, 'enum', opts);
+
 /*!
  * ignore
  */
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 62729eca174..a5d6bcc9195 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -259,6 +259,52 @@ SchemaNumber.prototype.max = function(value, message) {
   return this;
 };
 
+/**
+ * Sets a enum validator
+ *
+ * ####Example:
+ *
+ *     var s = new Schema({ n: { type: Number, enum: [1, 2, 3] });
+ *     var M = db.model('M', s);
+ *
+ *     var m = new M({ n: 4 });
+ *     await m.save(); // throws validation error
+ *
+ *     m.n = 3;
+ *     await m.save(); // succeeds
+ *
+ * @param {Array} values allowed values
+ * @param {String} [message] optional custom error message
+ * @return {SchemaType} this
+ * @see Customized Error Messages #error_messages_MongooseError-messages
+ * @api public
+ */
+
+SchemaNumber.prototype.enum = function(values, message) {
+  if (this.enumValidator) {
+    this.validators = this.validators.filter(function(v) {
+      return v.validator !== this.enumValidator;
+    }, this);
+  }
+
+  if (!Array.isArray(values)) {
+    values = Array.prototype.slice.call(arguments);
+    message = MongooseError.messages.Number.enum;
+  }
+
+  message = message == null ? MongooseError.messages.Number.enum : message;
+
+  this.enumValidator = v => v == null || values.indexOf(v) !== -1;
+  this.validators.push({
+    validator: this.enumValidator,
+    message: message,
+    type: 'enum',
+    enumValues: values
+  });
+
+  return this;
+};
+
 /**
  * Casts to number
  *
diff --git a/test/document.test.js b/test/document.test.js
index 7b466a47156..93d359f33ca 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8183,4 +8183,27 @@ describe('document', function() {
     p = new Parent({ child: new Child({}) });
     assert.strictEqual(p.child.toJSON().field, true);
   });
+
+  it('enum validator for document (gh-8139)', function() {
+    const schema = Schema({
+      num: {
+        type: Number,
+        enum: [1, 2, 3]
+      }
+    });
+    const Model = mongoose.model('gh8139', schema);
+
+    let doc = new Model({});
+    let err = doc.validateSync();
+    assert.ifError(err);
+
+    doc = new Model({ num: 4 });
+    err = doc.validateSync();
+    assert.ok(err);
+    assert.equal(err.errors['num'].name, 'ValidatorError');
+
+    doc = new Model({ num: 2 });
+    err = doc.validateSync();
+    assert.ifError(err);
+  });
 });

From 881bbbbde32a63b49439a3912c39bdbf375bf7b6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 08:19:35 -0800
Subject: [PATCH 0209/2348] feat(document): make `updateOne()` document
 middleware pass `this` to post hooks

Fix #8262
---
 lib/document.js       |  4 ++--
 test/document.test.js | 18 ++++++++++++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 465d405c700..0114d59fc31 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -696,10 +696,10 @@ Document.prototype.update = function update() {
 Document.prototype.updateOne = function updateOne(doc, options, callback) {
   const query = this.constructor.updateOne({_id: this._id}, doc, options);
   query._pre(cb => {
-    this.constructor._middleware.execPre('updateOne', this, [], cb);
+    this.constructor._middleware.execPre('updateOne', this, [this], cb);
   });
   query._post(cb => {
-    this.constructor._middleware.execPost('updateOne', this, [], {}, cb);
+    this.constructor._middleware.execPost('updateOne', this, [this], {}, cb);
   });
 
   if (this.$session() != null) {
diff --git a/test/document.test.js b/test/document.test.js
index 93d359f33ca..8f8a7dd8313 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -178,6 +178,24 @@ describe('document', function() {
       const doc = new Test({ x: 'test' });
       assert.ok(doc.updateOne() instanceof Test.Query);
     });
+
+    it('middleware (gh-8262)', function() {
+      const schema = new Schema({ x: String, y: String });
+      const docs = [];
+      schema.post('updateOne', { document: true, query: false }, function(doc, next) {
+        docs.push(doc);
+        next();
+      });
+      const Model = db.model('gh6940_3', schema);
+
+      return co(function*() {
+        const doc = yield Model.create({ x: 2, y: 4 });
+
+        yield doc.updateOne({ x: 4 });
+        assert.equal(docs.length, 1);
+        assert.equal(docs[0], doc);
+      });
+    });
   });
 
   describe('replaceOne', function() {

From c90dde7b745f312315905f0a3064511d21bd8834 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 08:23:53 -0800
Subject: [PATCH 0210/2348] test: fix tests re: #8262

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 8f8a7dd8313..ee06b8bcdff 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -186,7 +186,7 @@ describe('document', function() {
         docs.push(doc);
         next();
       });
-      const Model = db.model('gh6940_3', schema);
+      const Model = db.model('gh8262', schema);
 
       return co(function*() {
         const doc = yield Model.create({ x: 2, y: 4 });

From 67babb81da5f6d7de80f1086cc3ca9a8dab6efe1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 08:54:04 -0800
Subject: [PATCH 0211/2348] docs(error): add more detail about the
 ValidatorError class, including properties

Fix #8346
---
 lib/error/index.js | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/error/index.js b/lib/error/index.js
index 38c4d6cacb2..ec4188d61c9 100644
--- a/lib/error/index.js
+++ b/lib/error/index.js
@@ -102,7 +102,32 @@ MongooseError.CastError = require('./cast');
 MongooseError.ValidationError = require('./validation');
 
 /**
- * A `ValidationError` has a hash of `errors` that contain individual `ValidatorError` instances
+ * A `ValidationError` has a hash of `errors` that contain individual
+ * `ValidatorError` instances.
+ *
+ * ####Example:
+ *
+ *     const schema = Schema({ name: { type: String, required: true } });
+ *     const Model = mongoose.model('Test', schema);
+ *     const doc = new Model({});
+ *
+ *     // Top-level error is a ValidationError, **not** a ValidatorError
+ *     const err = doc.validateSync();
+ *     err instanceof mongoose.Error.ValidationError; // true
+ *
+ *     // A ValidationError `err` has 0 or more ValidatorErrors keyed by the
+ *     // path in the `err.errors` property.
+ *     err.errors['name'] instanceof mongoose.Error.ValidatorError;
+ *
+ *     err.errors['name'].kind; // 'required'
+ *     err.errors['name'].path; // 'name'
+ *     err.errors['name'].value; // undefined
+ *
+ * Instances of `ValidatorError` have the following properties:
+ *
+ * - `kind`: The validator's `type`, like `'required'` or `'regexp'`
+ * - `path`: The path that failed validation
+ * - `value`: The value that failed validation
  *
  * @api public
  * @memberOf Error

From de6f8b1ada414793030d2131b72ababaca2654a4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 10:43:39 -0800
Subject: [PATCH 0212/2348] feat(array): make `MongooseArray#push()` support
 using `$position`

Fix #4322
---
 lib/helpers/query/castUpdate.js |  4 +-
 lib/types/core_array.js         | 68 ++++++++++++++++++++++++++++++---
 lib/utils.js                    |  2 +-
 test/document.test.js           | 35 ++++++++++++++++-
 test/model.update.test.js       |  2 +-
 5 files changed, 100 insertions(+), 11 deletions(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 37a53b5a7e6..8bbf0d81d59 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -179,8 +179,8 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
             obj[key].$sort = val.$sort;
           }
 
-          if (!!val.$position || val.$position === 0) {
-            obj[key].$position = val.$position;
+          if (val.$position != null) {
+            obj[key].$position = castNumber(val.$position);
           }
         } else {
           try {
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index e9f2a54e799..dd587534707 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -2,6 +2,7 @@
 
 const Document = require('../document');
 const EmbeddedDocument = require('./embedded');
+const MongooseError = require('../error/mongooseError');
 const ObjectId = require('./objectid');
 const cleanModifiedSubpaths = require('../helpers/document/cleanModifiedSubpaths');
 const get = require('../helpers/get');
@@ -363,7 +364,11 @@ class CoreMongooseArray extends Array {
       }
     } else if (op === '$push') {
       atomics.$push = atomics.$push || { $each: [] };
-      atomics.$push.$each = atomics.$push.$each.concat(val);
+      if (val != null && utils.hasUserDefinedProperty(val, '$each')) {
+        atomics.$push = val;
+      } else {
+        atomics.$push.$each = atomics.$push.$each.concat(val);
+      }
     } else {
       atomics[op] = val;
     }
@@ -615,6 +620,23 @@ class CoreMongooseArray extends Array {
   /**
    * Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking.
    *
+   * ####Example:
+   *
+   *     const schema = Schema({ nums: [Number] });
+   *     const Model = mongoose.model('Test', schema);
+   *
+   *     const doc = await Model.create({ nums: [3, 4] });
+   *     doc.nums.push(5); // Add 5 to the end of the array
+   *     await doc.save();
+   *
+   *     // You can also pass an object with `$each` as the
+   *     // first parameter to use MongoDB's `$position`
+   *     doc.nums.push({
+   *       $each: [1, 2],
+   *       $position: 0
+   *     });
+   *     doc.nums; // [1, 2, 3, 4, 5]
+   *
    * @param {Object} [args...]
    * @api public
    * @method push
@@ -622,19 +644,53 @@ class CoreMongooseArray extends Array {
    */
 
   push() {
+    let values = arguments;
+    let atomic = values;
+    const isOverwrite = values[0] != null &&
+      utils.hasUserDefinedProperty(values[0], '$each');
+    if (isOverwrite) {
+      atomic = values[0];
+      values = values[0].$each;
+    }
+
     if (this[arraySchemaSymbol] == null) {
-      return _basePush.apply(this, arguments);
+      return _basePush.apply(this, values);
     }
 
-    _checkManualPopulation(this, arguments);
+    _checkManualPopulation(this, values);
 
     const parent = this[arrayParentSymbol];
-    let values = [].map.call(arguments, this._mapCast, this);
+    values = [].map.call(values, this._mapCast, this);
     values = this[arraySchemaSymbol].applySetters(values, parent, undefined,
       undefined, { skipDocumentArrayCast: true });
-    const ret = [].push.apply(this, values);
+    let ret;
+    const atomics = this[arrayAtomicsSymbol];
+
+    if (isOverwrite) {
+      atomic.$each = values;
+
+      if (get(atomics, '$push.$each.length', 0) > 0 &&
+          atomics.$push.$position != atomics.$position) {
+        throw new MongooseError('Cannot call `Array#push()` multiple times ' +
+          'with different `$position`');
+      }
 
-    this._registerAtomic('$push', values);
+      if (atomic.$position != null) {
+        [].splice.apply(this, [atomic.$position, 0].concat(values));
+        ret = this.length;
+      } else {
+        ret = [].push.apply(this, values);
+      }
+    } else {
+      if (get(atomics, '$push.$each.length', 0) > 0 &&
+          atomics.$push.$position != null) {
+        throw new MongooseError('Cannot call `Array#push()` multiple times ' +
+          'with different `$position`');
+      }
+      atomic = values;
+      ret = [].push.apply(this, values);
+    }
+    this._registerAtomic('$push', atomic);
     this._markModified();
     return ret;
   }
diff --git a/lib/utils.js b/lib/utils.js
index 8b35ebbaf40..33a77fb4b67 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -892,7 +892,7 @@ exports.hasUserDefinedProperty = function(obj, key) {
   if (_hasOwnProperty.call(obj, key)) {
     return true;
   }
-  if (key in obj) {
+  if (typeof obj === 'object' && key in obj) {
     const v = obj[key];
     return v !== Object.prototype[key] && v !== Array.prototype[key];
   }
diff --git a/test/document.test.js b/test/document.test.js
index ee06b8bcdff..9b707e9c0ad 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8209,7 +8209,7 @@ describe('document', function() {
         enum: [1, 2, 3]
       }
     });
-    const Model = mongoose.model('gh8139', schema);
+    const Model = db.model('gh8139', schema);
 
     let doc = new Model({});
     let err = doc.validateSync();
@@ -8224,4 +8224,37 @@ describe('document', function() {
     err = doc.validateSync();
     assert.ifError(err);
   });
+
+  it('array push with $position (gh-4322)', function() {
+    const schema = Schema({
+      nums: [Number]
+    });
+    const Model = db.model('gh4322', schema);
+
+    return co(function*() {
+      const doc = yield Model.create({ nums: [3, 4] });
+
+      doc.nums.push({
+        $each: [1, 2],
+        $position: 0
+      });
+      assert.deepEqual(doc.toObject().nums, [1, 2, 3, 4]);
+
+      yield doc.save();
+
+      const fromDb = yield Model.findOne({ _id: doc._id });
+      assert.deepEqual(fromDb.toObject().nums, [1, 2, 3, 4]);
+
+      doc.nums.push({
+        $each: [0],
+        $position: 0
+      });
+      assert.throws(() => {
+        doc.nums.push({ $each: [5] });
+      }, /Cannot call.*multiple times/);
+      assert.throws(() => {
+        doc.nums.push(5);
+      }, /Cannot call.*multiple times/);
+    });
+  });
 });
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 18f3ba25b98..de47adc85ae 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -829,7 +829,7 @@ describe('model: update:', function() {
       m.save(function(error, m) {
         assert.ifError(error);
         assert.equal(m.n.length, 1);
-        M.update(
+        M.updateOne(
           {name: '2.6'},
           {$push: {n: {$each: [{x: 2}, {x: 1}], $position: 0}}},
           function(error) {

From eb8cb79b7a6cbbac9555bd16632fb1d173c1afaf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 12:12:19 -0800
Subject: [PATCH 0213/2348] feat(schema): support setting `_id` as an option to
 single nested schema paths

Fix #8137
---
 lib/helpers/schema/addAutoId.js          |  7 ++++
 lib/options/SchemaSingleNestedOptions.js | 42 ++++++++++++++++++++++++
 lib/schema.js                            |  5 ++-
 lib/schema/SingleNestedPath.js           | 14 ++++++++
 test/schema.test.js                      | 35 ++++++++++++++++++++
 5 files changed, 100 insertions(+), 3 deletions(-)
 create mode 100644 lib/helpers/schema/addAutoId.js
 create mode 100644 lib/options/SchemaSingleNestedOptions.js

diff --git a/lib/helpers/schema/addAutoId.js b/lib/helpers/schema/addAutoId.js
new file mode 100644
index 00000000000..898863963db
--- /dev/null
+++ b/lib/helpers/schema/addAutoId.js
@@ -0,0 +1,7 @@
+'use strict';
+
+module.exports = function addAutoId(schema) {
+  const _obj = {_id: {auto: true}};
+  _obj._id[schema.options.typeKey] = 'ObjectId';
+  schema.add(_obj);
+};
\ No newline at end of file
diff --git a/lib/options/SchemaSingleNestedOptions.js b/lib/options/SchemaSingleNestedOptions.js
new file mode 100644
index 00000000000..c916d0fe2d8
--- /dev/null
+++ b/lib/options/SchemaSingleNestedOptions.js
@@ -0,0 +1,42 @@
+'use strict';
+
+const SchemaTypeOptions = require('./SchemaTypeOptions');
+
+/**
+ * The options defined on a single nested schematype.
+ *
+ * ####Example:
+ *
+ *     const schema = Schema({ child: Schema({ name: String }) });
+ *     schema.path('child').options; // SchemaSingleNestedOptions instance
+ *
+ * @api public
+ * @inherits SchemaTypeOptions
+ * @constructor SchemaSingleNestedOptions
+ */
+
+class SchemaSingleNestedOptions extends SchemaTypeOptions {}
+
+const opts = require('./propertyOptions');
+
+/**
+ * If set, overwrites the child schema's `_id` option.
+ *
+ * ####Example:
+ *
+ *     const childSchema = Schema({ name: String });
+ *     const parentSchema = Schema({
+ *       child: { type: childSchema, _id: false }
+ *     });
+ *     parentSchema.path('child').schema.options._id; // false
+ *
+ * @api public
+ * @property of
+ * @memberOf SchemaSingleNestedOptions
+ * @type Function|string
+ * @instance
+ */
+
+Object.defineProperty(SchemaSingleNestedOptions.prototype, '_id', opts);
+
+module.exports = SchemaSingleNestedOptions;
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index f2f04bc70f6..d94a33e2995 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -10,6 +10,7 @@ const MongooseError = require('./error/mongooseError');
 const SchemaType = require('./schematype');
 const SchemaTypeOptions = require('./options/SchemaTypeOptions');
 const VirtualType = require('./virtualtype');
+const addAutoId = require('./helpers/schema/addAutoId');
 const applyTimestampsToChildren = require('./helpers/update/applyTimestampsToChildren');
 const applyTimestampsToUpdate = require('./helpers/update/applyTimestampsToUpdate');
 const arrayParentSymbol = require('./helpers/symbols').arrayParentSymbol;
@@ -135,9 +136,7 @@ function Schema(obj, options) {
       (!this.options.noId && this.options._id) && !_idSubDoc;
 
   if (auto_id) {
-    const _obj = {_id: {auto: true}};
-    _obj._id[this.options.typeKey] = Schema.ObjectId;
-    this.add(_obj);
+    addAutoId(this);
   }
 
   this.setupTimestamp(this.options.timestamps);
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index ec7b8df6dbb..27be2b16b16 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -7,8 +7,10 @@
 const CastError = require('../error/cast');
 const EventEmitter = require('events').EventEmitter;
 const ObjectExpectedError = require('../error/objectExpected');
+const SchemaSingleNestedOptions = require('../options/SchemaSingleNestedOptions');
 const SchemaType = require('../schematype');
 const $exists = require('./operators/exists');
+const addAutoId = require('../helpers/schema/addAutoId');
 const castToNumber = require('./operators/helpers').castToNumber;
 const discriminator = require('../helpers/model/discriminator');
 const geospatial = require('./operators/geospatial');
@@ -31,6 +33,17 @@ module.exports = SingleNestedPath;
  */
 
 function SingleNestedPath(schema, path, options) {
+  if (options != null && options._id != null) {
+    schema = schema.clone();
+    if (!options._id) {
+      schema.remove('_id');
+      schema.options._id = false;
+    } else if (!schema.paths['_id']) {
+      addAutoId(schema);
+      schema.options._id = true;
+    }
+  }
+
   this.caster = _createConstructor(schema);
   this.caster.path = path;
   this.caster.prototype.$basePath = path;
@@ -45,6 +58,7 @@ function SingleNestedPath(schema, path, options) {
 
 SingleNestedPath.prototype = Object.create(SchemaType.prototype);
 SingleNestedPath.prototype.constructor = SingleNestedPath;
+SingleNestedPath.prototype.OptionsConstructor = SchemaSingleNestedOptions;
 
 /*!
  * ignore
diff --git a/test/schema.test.js b/test/schema.test.js
index b8b1d1dab51..dccbe8cc0d1 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2171,6 +2171,41 @@ describe('schema', function() {
     assert.equal(newSchema.path('title').options.type, String);
   });
 
+  it('supports defining `_id: false` on single nested paths (gh-8137)', function() {
+    let childSchema = Schema({ name: String });
+    let parentSchema = Schema({
+      child: {
+        type: childSchema,
+        _id: false
+      }
+    });
+
+    assert.ok(!parentSchema.path('child').schema.options._id);
+    assert.ok(childSchema.options._id);
+
+    let Parent = mongoose.model('gh8137', parentSchema);
+    let doc = new Parent({ child: { name: 'test' } });
+    assert.equal(doc.child._id, null);
+
+    childSchema = Schema({ name: String }, { _id: false });
+    parentSchema = Schema({
+      child: {
+        type: childSchema,
+        _id: true
+      }
+    });
+
+    assert.ok(parentSchema.path('child').schema.options._id);
+    assert.ok(parentSchema.path('child').schema.paths['_id']);
+    assert.ok(!childSchema.options._id);
+    assert.ok(!childSchema.paths['_id']);
+
+    mongoose.deleteModel(/gh8137/);
+    Parent = mongoose.model('gh8137', parentSchema);
+    doc = new Parent({ child: { name: 'test' } });
+    assert.ok(doc.child._id);
+  });
+
   describe('pick() (gh-8207)', function() {
     it('works with nested paths', function() {
       const schema = Schema({

From b82af9f2a85db5d5f2ae8842e20e1b9ea83c22d3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 14:03:04 -0800
Subject: [PATCH 0214/2348] test(populate): add test for #6608

---
 test/model.populate.test.js | 43 +++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5877e3d2ca2..58bafe69d59 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8828,5 +8828,48 @@ describe('model: populate:', function() {
         assert.ok(docs[0].virtualField[0].main);
       });
     });
+
+    it.skip('virtual populate with multiple `localField` and `foreignField` (gh-6608)', function() {
+      const employeeSchema = Schema({
+        locationId: String,
+        departmentId: String,
+        name: String
+      });
+
+      employeeSchema.virtual('department', {
+        ref: 'gh6608_Department',
+        localField: ['locationId', 'departmentId'],
+        foreignField: ['locationId', 'name'],
+        justOne: true
+      });
+
+      const departmentSchema = Schema({
+        locationId: String,
+        name: String
+      });
+
+      return co(function*() {
+        const Employee = db.model('gh6608_Employee', employeeSchema);
+        const Department = db.model('gh6608_Department', departmentSchema);
+
+        yield Employee.create([
+          { locationId: 'Miami', department: 'Engineering', name: 'Valeri Karpov' },
+          { locationId: 'Miami', department: 'Accounting', name: 'Test 1' },
+          { locationId: 'New York', department: 'Engineering', name: 'Test 2' }
+        ]);
+
+        const [dept] = yield Department.create([
+          { locationId: 'Miami', name: 'Engineering' },
+          { locationId: 'Miami', name: 'Accounting' },
+          { locationId: 'New York', name: 'Engineering' }
+        ]);
+
+        console.log('--------');
+        const doc = yield Employee.findOne({ name: 'Valeri Karpov' }).
+          populate('department');
+        assert.equal(doc.department._id.toHexString(), dept._id.toHexString());
+        assert.equal(doc.department.name, 'Engineering');
+      });
+    });
   });
 });

From 3fdd62ceda3caa11a431de9afc13cdb8b6791ec4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 14:16:52 -0800
Subject: [PATCH 0215/2348] feat(document): add `pathsToValidate` parameter to
 `Document#validate()`

Re: #7587
---
 lib/document.js       | 37 ++++++++++++++++++++++++++-----------
 test/document.test.js | 27 ++++++++++++++++++++++++++-
 2 files changed, 52 insertions(+), 12 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0114d59fc31..14023234a99 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1985,20 +1985,26 @@ Document.prototype.isDirectSelected = function isDirectSelected(path) {
  *       else // validation passed
  *     });
  *
- * @param {Object} optional options internal options
- * @param {Function} callback optional callback called after validation completes, passing an error if one occurred
+ * @param {Array|String} [pathsToValidate] list of paths to validate. If set, Mongoose will validate only the modified paths that are in the given list.
+ * @param {Object} [options] internal options
+ * @param {Function} [callback] optional callback called after validation completes, passing an error if one occurred
  * @return {Promise} Promise
  * @api public
  */
 
-Document.prototype.validate = function(options, callback) {
-  if (typeof options === 'function') {
-    callback = options;
+Document.prototype.validate = function(pathsToValidate, options, callback) {
+  if (typeof pathsToValidate === 'function') {
+    callback = pathsToValidate;
     options = null;
+    pathsToValidate = null;
+  } else if (typeof options === 'function') {
+    callback = options;
+    options = pathsToValidate;
+    pathsToValidate = null;
   }
 
   return utils.promiseOrCallback(callback, cb => {
-    this.$__validate(options, function(error) {
+    this.$__validate(pathsToValidate, options, function(error) {
       cb(error);
     });
   }, this.constructor.events);
@@ -2136,8 +2142,12 @@ function _getPathsToValidate(doc) {
  * ignore
  */
 
-Document.prototype.$__validate = function(options, callback) {
-  if (typeof options === 'function') {
+Document.prototype.$__validate = function(pathsToValidate, options, callback) {
+  if (typeof pathsToValidate === 'function') {
+    callback = pathsToValidate;
+    options = null;
+    pathsToValidate = null;
+  }else if (typeof options === 'function') {
     callback = options;
     options = null;
   }
@@ -2188,11 +2198,16 @@ Document.prototype.$__validate = function(options, callback) {
 
   // only validate required fields when necessary
   const pathDetails = _getPathsToValidate(this);
-  const paths = shouldValidateModifiedOnly ?
+  let paths = shouldValidateModifiedOnly ?
     pathDetails[0].filter((path) => this.isModified(path)) :
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
 
+  if (Array.isArray(pathsToValidate)) {
+    const _pathsToValidate = new Set(pathsToValidate);
+    paths = paths.filter(p => _pathsToValidate.has(p));
+  }
+
   if (paths.length === 0) {
     return process.nextTick(function() {
       const error = _complete();
@@ -2282,8 +2297,8 @@ Document.prototype.$__validate = function(options, callback) {
  * ####Example:
  *
  *     var err = doc.validateSync();
- *     if ( err ){
- *       handleError( err );
+ *     if (err) {
+ *       handleError(err);
  *     } else {
  *       // validation passed
  *     }
diff --git a/test/document.test.js b/test/document.test.js
index 9b707e9c0ad..3d041cf065f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8202,7 +8202,7 @@ describe('document', function() {
     assert.strictEqual(p.child.toJSON().field, true);
   });
 
-  it('enum validator for document (gh-8139)', function() {
+  it('enum validator for number (gh-8139)', function() {
     const schema = Schema({
       num: {
         type: Number,
@@ -8225,6 +8225,31 @@ describe('document', function() {
     assert.ifError(err);
   });
 
+  it('support `pathsToValidate()` option for `validate()` (gh-7587)', function() {
+    const schema = Schema({
+      name: {
+        type: String,
+        required: true
+      },
+      age: {
+        type: Number,
+        required: true
+      },
+      rank: String
+    });
+    const Model = db.model('gh7587_0', schema);
+
+    return co(function*() {
+      const doc = new Model({});
+
+      let err = yield doc.validate(['name', 'rank']).catch(err => err);
+      assert.deepEqual(Object.keys(err.errors), ['name']);
+
+      err = yield doc.validate(['age', 'rank']).catch(err => err);
+      assert.deepEqual(Object.keys(err.errors), ['age']);
+    });
+  });
+
   it('array push with $position (gh-4322)', function() {
     const schema = Schema({
       nums: [Number]

From 2e6b4900730c44118178c0c0fe1243c30f4c5d70 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 14:18:04 -0800
Subject: [PATCH 0216/2348] style: fix lint

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 14023234a99..4daa85b280d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2147,7 +2147,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     callback = pathsToValidate;
     options = null;
     pathsToValidate = null;
-  }else if (typeof options === 'function') {
+  } else if (typeof options === 'function') {
     callback = options;
     options = null;
   }

From cee7bc988c0148b03954610fa2ecc4b51faaae43 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 16:09:29 -0800
Subject: [PATCH 0217/2348] feat(model): add PoC for Model.validate()

Re: #7587
---
 lib/model.js       | 100 +++++++++++++++++++++++++++++++++++++++++++++
 test/model.test.js |  51 +++++++++++++++++++++++
 2 files changed, 151 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index bd548293190..5c4d932bfaa 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -18,6 +18,7 @@ const Query = require('./query');
 const RemoveOptions = require('./options/removeOptions');
 const SaveOptions = require('./options/saveOptions');
 const Schema = require('./schema');
+const ValidationError = require('./error/validation');
 const VersionError = require('./error/version');
 const ParallelSaveError = require('./error/parallelSave');
 const applyQueryMiddleware = require('./helpers/query/applyQueryMiddleware');
@@ -3884,6 +3885,105 @@ Model.aggregate = function aggregate(pipeline, callback) {
   return aggregate;
 };
 
+/**
+ * Casts and validates the given object against this model's schema, passing the
+ * given `context` to custom validators.
+ *
+ * ####Example:
+ *
+ *     const Model = mongoose.model('Test', Schema({
+ *       name: { type: String, required: true },
+ *       age: { type: Number, required: true }
+ *     });
+ *
+ *     try {
+ *       await Model.validate({ name: null }, ['name'])
+ *     } catch (err) {
+ *       err instanceof mongoose.Error.ValidationError; // true
+ *       Object.keys(err.errors); // ['name']
+ *     }
+ *
+ * @param {Object} obj
+ * @param {Array} pathsToValidate
+ * @param {Object} [context]
+ * @param {Function} [callback]
+ * @return {Promise|undefined}
+ * @api public
+ */
+
+Model.validate = function validate(obj, pathsToValidate, context, callback) {
+  return utils.promiseOrCallback(callback, cb => {
+    const schema = this.schema;
+    let paths = Object.keys(schema.paths);
+
+    if (pathsToValidate != null) {
+      const _pathsToValidate = new Set(pathsToValidate);
+      paths = paths.filter(p => {
+        const pieces = p.split('.');
+        let cur = pieces[0];
+        for (let i = 0; i < pieces.length; ++i) {
+          if (_pathsToValidate.has(cur)) {
+            return true;
+          }
+          cur += '.' + pieces[i];
+        }
+        return _pathsToValidate.has(p); 
+      });
+    }
+
+    let remaining = paths.length;
+    let error = null;
+    for (const path of paths) {
+      const schematype = schema.path(path);
+      if (schematype == null) {
+        _checkDone();
+        continue;
+      }
+
+      const pieces = path.split('.');
+      let cur = obj;
+      for (let i = 0; i < pieces.length - 1; ++i) {
+        cur = cur[pieces[i]];
+      }
+
+      let val = get(obj, path, void 0);
+
+      if (val != null) {
+        try {
+          val = schematype.cast(val);
+          cur[pieces[pieces.length - 1]] = val;
+        } catch (err) {
+          error = error || new ValidationError();
+          error.addError(path, err);
+  
+          _checkDone();
+          continue;
+        }
+      }
+
+      schematype.doValidate(val, err => {
+        if (err) {
+          error = error || new ValidationError();
+          if (err instanceof ValidationError) {
+            for (const _err of Object.keys(err.errors)) {
+              error.addError(`${path}.${err.errors[_err].path}`, _err);
+            }
+          } else {
+            error.addError(err.path, err);
+          }
+        }
+        _checkDone();
+      }, context);
+    }
+
+    function _checkDone() {
+      if (--remaining <= 0) {
+        return cb(error);
+      }
+    }
+  });
+};
+
 /**
  * Implements `$geoSearch` functionality for Mongoose
  *
diff --git a/test/model.test.js b/test/model.test.js
index fc6c2b40a20..8cfdb9e02a8 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6551,4 +6551,55 @@ describe('Model', function() {
         then(res => assert.ok(res));
     });
   });
+
+  it('Model.validate() (gh-7587)', function() {
+    const Model = db.model('gh7587', new Schema({
+      name: {
+        first: {
+          type: String,
+          required: true
+        },
+        last: {
+          type: String,
+          required: true
+        }
+      },
+      age: {
+        type: Number,
+        required: true
+      },
+      comments: [{ name: { type: String, required: true } }]
+    }));
+
+    return co(function*() {
+      let err = null;
+      let obj = null;
+
+      err = yield Model.validate({ age: null }, ['age']).
+        then(() => null, err => err);
+      assert.ok(err);
+      assert.deepEqual(Object.keys(err.errors), ['age']);
+
+      err = yield Model.validate({ name: {} }, ['name']).
+        then(() => null, err => err);
+      assert.ok(err);
+      assert.deepEqual(Object.keys(err.errors), ['name.first', 'name.last']);
+
+      obj = { name: { first: 'foo' } };
+      err = yield Model.validate(obj, ['name']).
+        then(() => null, err => err);
+      assert.ok(err);
+      assert.deepEqual(Object.keys(err.errors), ['name.last']);
+
+      obj = { comments: [{ name: 'test' }, {}] };
+      err = yield Model.validate(obj, ['comments']).
+        then(() => null, err => err);
+      assert.ok(err);
+      assert.deepEqual(Object.keys(err.errors), ['comments.name']);
+
+      obj = { age: '42' };
+      yield Model.validate(obj, ['age']);
+      assert.strictEqual(obj.age, 42);
+    });
+  });
 });

From 11f7bd534b7b24ef39d9750a64987de2fa1ca3a5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 16:11:26 -0800
Subject: [PATCH 0218/2348] test: fix tests

---
 test/model.populate.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 58bafe69d59..2ca2b2855bf 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8858,13 +8858,13 @@ describe('model: populate:', function() {
           { locationId: 'New York', department: 'Engineering', name: 'Test 2' }
         ]);
 
-        const [dept] = yield Department.create([
+        const depts = yield Department.create([
           { locationId: 'Miami', name: 'Engineering' },
           { locationId: 'Miami', name: 'Accounting' },
           { locationId: 'New York', name: 'Engineering' }
         ]);
+        const dept = depts[0];
 
-        console.log('--------');
         const doc = yield Employee.findOne({ name: 'Valeri Karpov' }).
           populate('department');
         assert.equal(doc.department._id.toHexString(), dept._id.toHexString());

From 77dd672c0138f342311b9bbb0b206ee2fea5bdf7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 16:19:34 -0800
Subject: [PATCH 0219/2348] chore: add SECURITY.md

---
 SECURITY.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 SECURITY.md

diff --git a/SECURITY.md b/SECURITY.md
new file mode 100644
index 00000000000..41b89d8347d
--- /dev/null
+++ b/SECURITY.md
@@ -0,0 +1 @@
+Please follow the instructions on [Tidelift's security page](https://tidelift.com/docs/security) to report a security issue.

From dc9272c3efa7e0295b63b672c7d0fa3e603ee251 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 21 Nov 2019 16:24:02 -0800
Subject: [PATCH 0220/2348] chore: remove nyc for now

---
 package.json | 1 -
 1 file changed, 1 deletion(-)

diff --git a/package.json b/package.json
index b62f2f67abe..4688a4e36e7 100644
--- a/package.json
+++ b/package.json
@@ -55,7 +55,6 @@
     "mongodb-topology-manager": "1.0.11",
     "mongoose-long": "0.2.1",
     "node-static": "0.7.11",
-    "nyc": "14.1.1",
     "object-sizeof": "1.3.0",
     "promise-debug": "0.1.1",
     "pug": "2.0.3",

From a8bcc8e7cc3dce1c5d885009a73133bb70af2b8a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 Nov 2019 19:20:30 -0800
Subject: [PATCH 0221/2348] chore: add funding info

---
 package.json | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/package.json b/package.json
index 4688a4e36e7..f92c7425257 100644
--- a/package.json
+++ b/package.json
@@ -150,5 +150,9 @@
         }
       ]
     }
+  },
+  "funding": {
+    "type": "opencollective",
+    "url": "https://opencollective.com/mongoose"
   }
 }

From cfbaf0f6d097916c99aa19caa68899f1edb31479 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 24 Nov 2019 13:23:30 -0800
Subject: [PATCH 0222/2348] refactor: remove unnecessary code from fix for
 #6398

---
 lib/types/documentarray.js | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 7fa1bec2689..bb1ce19ce71 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -392,12 +392,6 @@ function MongooseDocumentArray(values, path, doc) {
         !arr[arraySchemaSymbol].$isMongooseDocumentArray) {
       arr[arraySchemaSymbol] = arr[arraySchemaSymbol].casterConstructor;
     }
-
-    // Tricky but this may be a document array embedded in a normal array,
-    // in which case `path` would point to the embedded array. See #6405, #6398
-    if (arr[arraySchemaSymbol] && !arr[arraySchemaSymbol].$isMongooseDocumentArray) {
-      arr[arraySchemaSymbol] = arr[arraySchemaSymbol].casterConstructor;
-    }
   }
 
   return arr;

From 51c6776a9a67368cd2cb1cf170996912353ee204 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 25 Nov 2019 17:40:32 -0500
Subject: [PATCH 0223/2348] refactor(schema): add array.$, array.$.$ subpaths
 for nested arrays

Fix #6405
---
 lib/schema.js | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 1aac5594522..2504c14059c 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -672,16 +672,17 @@ Schema.prototype.path = function(path, obj) {
     let arrayPath = path;
     let _schemaType = schemaType;
 
-    let toAdd = [];
+    const toAdd = [];
     while (_schemaType.$isMongooseArray) {
       arrayPath = arrayPath + '.$';
 
       // Skip arrays of document arrays
       if (_schemaType.$isMongooseDocumentArray) {
-        toAdd = [];
-        break;
+        _schemaType = _schemaType.$embeddedSchemaType.clone();
+      } else {
+        _schemaType = _schemaType.caster.clone();
       }
-      _schemaType = _schemaType.caster.clone();
+
       _schemaType.path = arrayPath;
       toAdd.push(_schemaType);
     }

From 68cdc334b5aeda2c26f9333856ad5b445264586d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Nov 2019 15:41:37 -0500
Subject: [PATCH 0224/2348] fix: upgrade mongodb driver -> 3.3.5

Fix #8383
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index f92c7425257..779375c2ddf 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.3.4",
+    "mongodb": "3.3.5",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From e6616d7fc850beda97958eef8b3dd5ebc66379a6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Nov 2019 15:59:56 -0500
Subject: [PATCH 0225/2348] test: fix one test re: #8383

---
 lib/connection.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index 2fbb4a67dae..f85ac988d07 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -670,6 +670,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
       if (options.useUnifiedTopology) {
         if (type === 'Single') {
           const server = Array.from(db.s.topology.s.servers.values())[0];
+
           server.s.pool.on('close', () => {
             _this.readyState = STATES.disconnected;
           });
@@ -682,6 +683,11 @@ Connection.prototype.openUri = function(uri, options, callback) {
           server.s.pool.on('timeout', () => {
             _this.emit('timeout');
           });
+          server.s.pool.on('drain', err => {
+            if (err && err.name === 'MongoNetworkError') {
+              _this.emit('timeout');
+            }
+          });
         } else if (type.startsWith('ReplicaSet')) {
           db.on('close', function() {
             const type = get(db, 's.topology.s.description.type', '');

From 02047ca4ec569de0697666e0538b19c1019638ad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 27 Nov 2019 18:57:21 -0500
Subject: [PATCH 0226/2348] fix(connection): correctly bubble up timeout and
 disconnected events re: #8383

---
 lib/connection.js       | 8 ++++----
 test/connection.test.js | 5 +++++
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index f85ac988d07..ed1d5b56dd2 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -671,9 +671,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
         if (type === 'Single') {
           const server = Array.from(db.s.topology.s.servers.values())[0];
 
-          server.s.pool.on('close', () => {
-            _this.readyState = STATES.disconnected;
-          });
           server.s.topology.on('serverHeartbeatSucceeded', () => {
             _handleReconnect();
           });
@@ -683,8 +680,11 @@ Connection.prototype.openUri = function(uri, options, callback) {
           server.s.pool.on('timeout', () => {
             _this.emit('timeout');
           });
+          client.on('serverClosed', () => {
+            _this.readyState = STATES.disconnected;
+          });
           server.s.pool.on('drain', err => {
-            if (err && err.name === 'MongoNetworkError') {
+            if (err && err.name === 'MongoNetworkError' && err.message.endsWith('timed out')) {
               _this.emit('timeout');
             }
           });
diff --git a/test/connection.test.js b/test/connection.test.js
index b8cf36d5413..9515a694e27 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -188,6 +188,7 @@ describe('connections:', function() {
         let numDisconnected = 0;
         let numReconnected = 0;
         let numReconnect = 0;
+        let numTimeout = 0;
         let numClose = 0;
         const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest?heartbeatfrequencyms=1000', {
           useNewUrlParser: true,
@@ -203,6 +204,9 @@ describe('connections:', function() {
         conn.on('reconnect', function() {
           ++numReconnect;
         });
+        conn.on('timeout', function() {
+          ++timeout;
+        });
         // Same as `reconnect`, just for backwards compat
         conn.on('reconnected', function() {
           ++numReconnected;
@@ -241,6 +245,7 @@ describe('connections:', function() {
             assert.equal(numDisconnected, 1);
             assert.equal(numReconnected, 1);
             assert.equal(numReconnect, 1);
+            assert.equal(numTimeout, 0);
             assert.equal(numClose, 0);
 
             conn.close();

From a7923971a81695012e5d9f27053dd4baabfeb9cb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 27 Nov 2019 19:00:05 -0500
Subject: [PATCH 0227/2348] style: fix lint

---
 test/connection.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index 9515a694e27..170d0782380 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -205,7 +205,7 @@ describe('connections:', function() {
           ++numReconnect;
         });
         conn.on('timeout', function() {
-          ++timeout;
+          ++numTimeout;
         });
         // Same as `reconnect`, just for backwards compat
         conn.on('reconnected', function() {

From 9f0a9a985785fdf7826a7b20885b7e3f8b425719 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 28 Nov 2019 08:24:58 -0500
Subject: [PATCH 0228/2348] chore: debug for #8383

---
 test/connection.test.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index 170d0782380..7a3ca8a0d67 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -341,6 +341,7 @@ describe('connections:', function() {
         });
 
         conn.on('disconnected', function() {
+          console.log('Disconnected', new Error().stack);
           ++numDisconnected;
         });
 

From ca527f41783c016a5c992a7e4a0c751870dbdfe5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 28 Nov 2019 08:36:12 -0500
Subject: [PATCH 0229/2348] fix: use serverDescriptionChanged event to
 distinguish between timeout vs disconnected re: #8383

---
 lib/connection.js       | 17 +++++++++--------
 test/connection.test.js |  1 -
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index ed1d5b56dd2..ff75f118786 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -677,15 +677,16 @@ Connection.prototype.openUri = function(uri, options, callback) {
           server.s.pool.on('reconnect', () => {
             _handleReconnect();
           });
-          server.s.pool.on('timeout', () => {
-            _this.emit('timeout');
-          });
-          client.on('serverClosed', () => {
-            _this.readyState = STATES.disconnected;
-          });
-          server.s.pool.on('drain', err => {
-            if (err && err.name === 'MongoNetworkError' && err.message.endsWith('timed out')) {
+          client.on('serverDescriptionChanged', ev => {
+            const newDescription = ev.newDescription;
+            if (newDescription.type === 'Standalone') {
+              _handleReconnect();
+            } else if (newDescription.error != null &&
+              newDescription.error.name === 'MongoNetworkError' &&
+              newDescription.error.message.endsWith('timed out')) {
               _this.emit('timeout');
+            } else {
+              _this.readyState = STATES.disconnected;
             }
           });
         } else if (type.startsWith('ReplicaSet')) {
diff --git a/test/connection.test.js b/test/connection.test.js
index 7a3ca8a0d67..170d0782380 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -341,7 +341,6 @@ describe('connections:', function() {
         });
 
         conn.on('disconnected', function() {
-          console.log('Disconnected', new Error().stack);
           ++numDisconnected;
         });
 

From 44ad5d432d51fc3047b349f783a6bf366efafea9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 29 Nov 2019 08:58:19 -0500
Subject: [PATCH 0230/2348] chore: release 5.7.13

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 6110027d00b..3351904aefa 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.7.13 / 2019-11-29
+===================
+ * fix: upgrade mongodb driver -> 3.3.5 #8383
+ * fix(model): catch the error when insertMany fails to initialize the document #8365 #8363 [Fonger](https://github.com/Fonger)
+ * fix(schema): add array.$, array.$.$ subpaths for nested arrays #6405
+ * docs(error): add more detail about the ValidatorError class, including properties #8346
+ * docs(connection): document `Connection#models` property #8314
+
 5.7.12 / 2019-11-19
 ===================
  * fix: avoid throwing error if calling `push()` on a doc array with no parent #8351 #8317 #8312 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 779375c2ddf..cefd1add9c9 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.13-pre",
+  "version": "5.7.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 58c8e41e5840426619507b53afa493c28027c5e7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 30 Nov 2019 18:39:47 -0500
Subject: [PATCH 0231/2348] chore: add tidelift marketing

---
 README.md            |  10 +++-
 docs/enterprise.pug  | 108 +++++++++++++++++++++++++++++++++++++++++++
 docs/layout.pug      |   2 +
 docs/source/index.js |   1 +
 4 files changed, 119 insertions(+), 2 deletions(-)
 create mode 100644 docs/enterprise.pug

diff --git a/README.md b/README.md
index ebfcbb93bcd..e6e3914f702 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed
 
 ## Documentation
 
-[mongoosejs.com](http://mongoosejs.com/)
+The official documentation website is [mongoosejs.com](http://mongoosejs.com/).
 
 [Mongoose 5.0.0](https://github.com/Automattic/mongoose/blob/master/History.md#500--2018-01-17) was released on January 17, 2018. You can find more details on [backwards breaking changes in 5.0.0 on our docs site](https://mongoosejs.com/docs/migrating_to_5.html).
 
@@ -39,7 +39,7 @@ View all 400+ [contributors](https://github.com/Automattic/mongoose/graphs/contr
 
 ## Installation
 
-First install [node.js](http://nodejs.org/) and [mongodb](https://www.mongodb.org/downloads). Then:
+First install [Node.js](http://nodejs.org/) and [MongoDB](https://www.mongodb.org/downloads). Then:
 
 ```sh
 $ npm install mongoose
@@ -55,6 +55,12 @@ const mongoose = require('mongoose');
 import mongoose from 'mongoose';
 ```
 
+## Mongoose for Enterprise
+
+Available as part of the Tidelift Subscription
+
+The maintainers of mongoose and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. [Learn more.](https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise&utm_term=repo)
+
 ## Overview
 
 ### Connecting to MongoDB
diff --git a/docs/enterprise.pug b/docs/enterprise.pug
new file mode 100644
index 00000000000..13df7b14d54
--- /dev/null
+++ b/docs/enterprise.pug
@@ -0,0 +1,108 @@
+extends layout
+
+append style
+  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
+  script(type="text/javascript" src="/docs/js/native.js")
+
+  style.
+    button {
+      border-radius: 3px;
+      padding: 3px;
+      padding-left: 30px;
+      padding-right: 30px;
+    }
+
+    button.btn-white {
+      border: 1px solid #800;
+      color: #800;
+    }
+
+    button.btn-color {
+      border: 1px solid transparent;
+      color: white;
+      background-color: #800;
+    }
+
+block content
+  :markdown
+    ## Mongoose for Enterprise
+
+    <script>
+      _native.init("CK7DT53U",{
+        targetClass: 'native-inline'
+      });
+    </script>
+
+    <div class="native-inline">
+      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
+    </div>
+
+    ### Available as part of the Tidelift Subscription
+    
+    Tidelift is working with the maintainers of Mongoose and thousands of other
+    open source projects to deliver commercial support and maintenance for the
+    open source dependencies you use to build your applications. Save time,
+    reduce risk, and improve code health, while paying the maintainers of the
+    exact dependencies you use.
+
+    <a href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+      <button class="btn-white">Learn More</button>
+    </a>
+    <a href="https://tidelift.com/subscription/request-a-demo?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+      <button class="btn-color">Request a Demo</button>
+    </a>
+
+    ### Enterprise-ready open source software—managed for you
+
+    The Tidelift Subscription is a managed open source subscription for application
+    dependencies covering millions of open source projects across JavaScript,
+    Python, Java, PHP, Ruby, .NET, and more.
+
+    Your subscription includes:
+
+    - Security updates
+
+    Tidelift’s security response team coordinates patches for new breaking security
+    vulnerabilities and alerts immediately through a private channel, so your
+    software supply chain is always secure.
+
+    - Licensing verification and indemnification
+
+    Tidelift verifies license information to enable easy policy enforcement and
+    adds intellectual property indemnification to cover creators and users in case
+    something goes wrong. You always have a 100% up-to-date bill of materials for
+    your dependencies to share with your legal team, customers, or partners.
+
+    - Maintenance and code improvement
+
+    Tidelift ensures the software you rely on keeps working as long as you need it
+    to work. Your managed dependencies are actively maintained and we recruit
+    additional maintainers where required.
+
+    - Package selection and version guidance
+
+    We help you choose the best open source packages from the start—and then
+    guide you through updates to stay on the best releases as new issues arise.
+
+    - Roadmap input
+
+    Take a seat at the table with the creators behind the software you use.
+    Tidelift’s participating maintainers earn more income as their software is
+    used by more subscribers, so they’re interested in knowing what you need.
+
+    - Tooling and cloud integration
+
+    Tidelift works with GitHub, GitLab, BitBucket, and more. We support every
+    cloud platform (and other deployment targets, too).
+
+    The end result? All of the capabilities you expect from commercial-grade
+    software, for the full breadth of open source you use. That means less time
+    grappling with esoteric open source trivia, and more time building your own
+    applications—and your business.
+
+    <a href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+      <button class="btn-white">Learn More</button>
+    </a>
+    <a href="https://tidelift.com/subscription/request-a-demo?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+      <button class="btn-color">Request a Demo</button>
+    </a>
diff --git a/docs/layout.pug b/docs/layout.pug
index bc8edd192f9..fb6f9455bdd 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -113,6 +113,8 @@ html(lang='en')
                 a.pure-menu-link(href="/docs/faq.html") FAQ
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/further_reading.html") Further Reading
+              li.pure-menu-item
+                a.pure-menu-link(href="/docs/enterprise.html") For Enterprise
             div.cpc-ad
               <script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script>
         .container
diff --git a/docs/source/index.js b/docs/source/index.js
index d6b6b55f68a..6687cf57065 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -32,3 +32,4 @@ exports['docs/compatibility.pug'] = {
   guide: true
 };
 exports['docs/search.pug'] = { title: 'Search' };
+exports['docs/enterprise.pug'] = { title: 'Mongoose for Enterprise' };

From 62480732c1fbe199f3ead728368334faf2d66217 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 1 Dec 2019 11:03:45 -0500
Subject: [PATCH 0232/2348] test(map): repro #8357

---
 test/types.map.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index df99d479a5e..aee37832760 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -743,4 +743,20 @@ describe('Map', function() {
     assert.ok(err.errors['myMap.foo.test'].message.indexOf('required') !== -1,
       err.errors['myMap.foo.test'].message);
   });
+
+  it('works with clone() (gh-8357)', function() {
+    const childSchema = mongoose.Schema({ name: String });
+    const schema = mongoose.Schema({
+      myMap: {
+        type: Map,
+        of: childSchema
+      }
+    });
+    const Model = db.model('gh8357', schema.clone());
+
+    const doc = new Model({ myMap: { foo: { name: 'bar' } } });
+
+    const err = doc.validateSync();
+    assert.ifError(err);
+  });
 });

From a5678166319639a96a8d7e2cce937418125232f0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 1 Dec 2019 11:03:58 -0500
Subject: [PATCH 0233/2348] fix(map): handle cloning a schema that has a map of
 subdocuments

Fix #8357
---
 lib/schema/map.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/lib/schema/map.js b/lib/schema/map.js
index b6f7feeafdb..14fd248e832 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -41,6 +41,15 @@ class Map extends SchemaType {
 
     return new MongooseMap(val, this.path, doc, this.$__schemaType);
   }
+
+  clone() {
+    const schematype = super.clone();
+
+    if (this.$__schemaType != null) {
+      schematype.$__schemaType = this.$__schemaType.clone();
+    }
+    return schematype;
+  }
 }
 
 Map.prototype.OptionsConstructor = SchemaMapOptions;

From efe57c110bcde49e0c4a919c0fb7f3efdc86c73b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 1 Dec 2019 11:04:59 -0500
Subject: [PATCH 0234/2348] chore: now working on 5.7.14

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index cefd1add9c9..cce6a944c8d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.13",
+  "version": "5.7.14-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From cee91527be3b20f8800bd0a5006ab35aea212ee3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Dec 2019 09:26:44 -0500
Subject: [PATCH 0235/2348] chore: remove Novembers dropped opencollective
 sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index 9a8aae1354f..57354c3f748 100644
--- a/index.pug
+++ b/index.pug
@@ -214,9 +214,6 @@ html(lang='en')
               <a href="https://blokt.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fblokt.com&height=100" style="height:100px">
               </a>
-              <a href="https://usave.co.uk/utilities/broadband/">
-                <img class="sponsor" title="Compare broadband deals with usave" src="https://usave.co.uk/img/brand/brand-logo.png" style="height:100px">
-              </a>
               <a href="http://clay.global/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F09d57c90-637c-11e7-9ed2-bfa12b0351e8.jpg&height=100" style="height: 100px">
               </a>
@@ -265,9 +262,6 @@ html(lang='en')
               <a href="https://www.bonus.com.de/freispiele">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-deutschland/646169e/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.bonus.ca">
-                <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo.png" style="height: 100px">
-              </a>
               <a href="https://www.crosswordsolver.com/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/crosswordsolver.png" style="height: 80px">
               </a>

From cb1bfb00a0e25cc8367c59f774877a77b509f8bb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Dec 2019 10:15:16 -0500
Subject: [PATCH 0236/2348] style: fix lint

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index afe28b4600a..d66dd42a413 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3932,7 +3932,7 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
           }
           cur += '.' + pieces[i];
         }
-        return _pathsToValidate.has(p); 
+        return _pathsToValidate.has(p);
       });
     }
 
@@ -3960,7 +3960,7 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
         } catch (err) {
           error = error || new ValidationError();
           error.addError(path, err);
-  
+
           _checkDone();
           continue;
         }

From d771d043631885226ffdc9ed5b9ce37aefa200ef Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Dec 2019 10:34:59 -0500
Subject: [PATCH 0237/2348] test(update): repro #3587

---
 test/updateValidators.unit.test.js | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/test/updateValidators.unit.test.js b/test/updateValidators.unit.test.js
index d92887e82c1..05777cff75a 100644
--- a/test/updateValidators.unit.test.js
+++ b/test/updateValidators.unit.test.js
@@ -81,7 +81,7 @@ describe('updateValidators', function() {
 
     it('doesnt flatten decimal128 (gh-7561)', function(done) {
       const Decimal128Type = require('../lib/types/decimal128');
-      const schema = new Schema({ test: { type: 'Decimal128', required: true } });
+      const schema = Schema({ test: { type: 'Decimal128', required: true } });
       const fn = updateValidators({}, schema, {
         test: new Decimal128Type('33.426')
       }, {});
@@ -90,5 +90,22 @@ describe('updateValidators', function() {
         done();
       });
     });
+
+    it('handles nested paths correctly (gh-3587)', function(done) {
+      const schema = Schema({
+        nested: {
+          a: { type: String, required: true },
+          b: { type: String, required: true }
+        }
+      });
+      const fn = updateValidators({}, schema, {
+        nested: { b: 'test' }
+      }, {});
+      fn(function(err) {
+        assert.ok(err);
+        assert.deepEqual(Object.keys(err.errors), ['nested.a']);
+        done();
+      });
+    });
   });
 });

From d8772bf81f5664945ab76d23852d61059f067db6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Dec 2019 10:35:33 -0500
Subject: [PATCH 0238/2348] fix(update): make update validators run on all
 subpaths when setting a nested path, even omitted subpaths

Fix #3587
---
 lib/helpers/common.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/helpers/common.js b/lib/helpers/common.js
index 3398f4cbe09..009f481fb12 100644
--- a/lib/helpers/common.js
+++ b/lib/helpers/common.js
@@ -34,6 +34,7 @@ function flatten(update, path, options, schema) {
 
     // Avoid going into mixed paths if schema is specified
     const keySchema = schema && schema.path && schema.path(path + key);
+    const isNested = schema && schema.nested && schema.nested[path + key];
     if (keySchema && keySchema.instance === 'Mixed') continue;
 
     if (shouldFlatten(val)) {
@@ -48,6 +49,15 @@ function flatten(update, path, options, schema) {
         result[path + key] = val;
       }
     }
+
+    if (isNested) {
+      const paths = Object.keys(schema.paths);
+      for (const p of paths) {
+        if (p.startsWith(path + key + '.') && !result.hasOwnProperty(p)) {
+          result[p] = void 0;
+        }
+      }
+    }
   }
 
   return result;

From acef6ef82a1f1e1366cb810aa9fdadaabf504d07 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Dec 2019 10:47:34 -0500
Subject: [PATCH 0239/2348] test: fix tests

---
 lib/helpers/query/hasDollarKeys.js | 3 +++
 lib/query.js                       | 1 -
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/query/hasDollarKeys.js b/lib/helpers/query/hasDollarKeys.js
index fa436d314ab..958e1c930e1 100644
--- a/lib/helpers/query/hasDollarKeys.js
+++ b/lib/helpers/query/hasDollarKeys.js
@@ -5,6 +5,9 @@
  */
 
 module.exports = function(obj) {
+  if (obj == null) {
+    return false;
+  }
   const keys = Object.keys(obj);
   const len = keys.length;
   for (let i = 0; i < len; ++i) {
diff --git a/lib/query.js b/lib/query.js
index d19a8ae3ce3..8e3cc5f97a4 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3705,7 +3705,6 @@ function _updateThunk(op, callback) {
 
   ++this._executionCount;
 
-  console.log('FT', this._update)
   this._update = utils.clone(this._update, options);
   const isOverwriting = this.options.overwrite && !hasDollarKeys(this._update);
   if (isOverwriting) {

From aeb2c4205a5c6292458d0d4766ebad25ebb32ee2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Dec 2019 11:42:12 -0500
Subject: [PATCH 0240/2348] feat(update): add minimal casting of update
 pipelines

To be consistent with `.aggregate()`, we don't do any casting of aggregation pipelines, because the shape of the document may change.

Fix #8225
---
 lib/helpers/query/castUpdate.js | 35 +++++++++++++++++++++++++--------
 test/model.update.test.js       | 11 ++++++++++-
 2 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 80b44feee4e..19c05ea6571 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const CastError = require('../../error/cast');
+const MongooseError = require('../../error/mongooseError');
 const StrictModeError = require('../../error/strict');
 const ValidationError = require('../../error/validation');
 const castNumber = require('../../cast/number');
@@ -30,9 +31,11 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
   // Update pipeline
   if (Array.isArray(obj)) {
     const len = obj.length;
-    options.pipeline = true;
     for (let i = 0; i < len; ++i) {
-      obj[i] = castUpdate(schema, obj[i], options, context, filter);
+      const ops = Object.keys(obj[i]);
+      for (const op of ops) {
+        obj[i][op] = castPipelineOperator(op, obj[i][op]);
+      }
     }
     return obj;
   }
@@ -85,10 +88,7 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
     val = ret[op];
     hasDollarKey = hasDollarKey || op.startsWith('$');
 
-    if (op === '$unset' && options.pipeline) {
-      hasKeys = true;
-      castPipelineOperator(op, val);
-    } else if (val &&
+    if (val &&
         typeof val === 'object' &&
         !Buffer.isBuffer(val) &&
         (!overwrite || hasDollarKey)) {
@@ -122,11 +122,30 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
 function castPipelineOperator(op, val) {
   if (op === '$unset') {
     if (!Array.isArray(val) || val.find(v => typeof v !== 'string')) {
-      throw new Error('Invalid $unset in pipeline, must be an array of strings');
+      throw new MongooseError('Invalid $unset in pipeline, must be ' +
+        'an array of strings');
+    }
+    return val;
+  }
+  if (op === '$project') {
+    if (val == null || typeof val !== 'object') {
+      throw new MongooseError('Invalid $project in pipeline, must be an object');
+    }
+    return val;
+  }
+  if (op === '$addFields' || op === '$set') {
+    if (val == null || typeof val !== 'object') {
+      throw new MongooseError('Invalid ' + op + ' in pipeline, must be an object');
     }
+    return val;
+  } else if (op === '$replaceRoot' || op === '$replaceWith') {
+    if (val == null || typeof val !== 'object') {
+      throw new MongooseError('Invalid ' + op + ' in pipeline, must be an object');
+    }
+    return val;
   }
 
-  return val;
+  throw new MongooseError('Invalid update pipeline operator: "' + op + '"');
 }
 
 /*!
diff --git a/test/model.update.test.js b/test/model.update.test.js
index a631241da83..8399a8b9cbf 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3403,9 +3403,18 @@ describe('model: updateOne: ', function() {
           { $set: { newProp: 'test2' } },
           { $unset: ['oldProp'] }
         ]);
-        const doc = yield Model.findOne();
+        let doc = yield Model.findOne();
         assert.equal(doc.newProp, 'test2');
         assert.strictEqual(doc.oldProp, void 0);
+
+        // Aliased fields
+        yield Model.updateOne({}, [
+          { $addFields: { oldProp: 'test3' } },
+          { $project: { newProp: 0 } }
+        ]);
+        doc = yield Model.findOne();
+        assert.equal(doc.oldProp, 'test3');
+        assert.strictEqual(doc.newProp, void 0);
       });
     });
   });

From b4811793be586fe7d7ff013cf1fee5892d8970d0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 3 Dec 2019 16:19:35 -0500
Subject: [PATCH 0241/2348] feat(schema): add ability to change CastError
 message using `cast` option to SchemaType

Fix #8300
---
 lib/error/cast.js                | 51 +++++++++++++++++++++------
 lib/options/SchemaTypeOptions.js | 31 +++++++++++++++++
 lib/schema/SingleNestedPath.js   |  2 +-
 lib/schema/array.js              |  4 +--
 lib/schema/boolean.js            |  2 +-
 lib/schema/buffer.js             |  6 ++--
 lib/schema/date.js               |  2 +-
 lib/schema/decimal128.js         |  4 +--
 lib/schema/documentarray.js      |  4 +--
 lib/schema/number.js             |  6 ++--
 lib/schema/objectid.js           |  4 +--
 lib/schema/string.js             |  4 +--
 lib/schematype.js                |  3 ++
 test/schema.test.js              | 59 ++++++++++++++++++++++++++++++++
 14 files changed, 152 insertions(+), 30 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 5fbee1301fd..87f1ce9327d 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -5,6 +5,7 @@
  */
 
 const MongooseError = require('./mongooseError');
+const get = require('../helpers/get');
 const util = require('util');
 
 /**
@@ -16,25 +17,29 @@ const util = require('util');
  * @api private
  */
 
-function CastError(type, value, path, reason) {
+function CastError(type, value, path, reason, schemaType) {
   let stringValue = util.inspect(value);
   stringValue = stringValue.replace(/^'/, '"').replace(/'$/, '"');
   if (!stringValue.startsWith('"')) {
     stringValue = '"' + stringValue + '"';
   }
-  MongooseError.call(this, 'Cast to ' + type + ' failed for value ' +
-    stringValue + ' at path "' + path + '"');
-  this.name = 'CastError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+
+  const messageFormat = get(schemaType, 'options.cast', null);
+  if (typeof messageFormat === 'string') {
+    this.messageFormat = schemaType.options.cast;
   }
   this.stringValue = stringValue;
   this.kind = type;
   this.value = value;
   this.path = path;
   this.reason = reason;
+  MongooseError.call(this, this.formatMessage());
+  this.name = 'CastError';
+  if (Error.captureStackTrace) {
+    Error.captureStackTrace(this);
+  } else {
+    this.stack = new Error().stack;
+  }
 }
 
 /*!
@@ -50,9 +55,33 @@ CastError.prototype.constructor = MongooseError;
 
 CastError.prototype.setModel = function(model) {
   this.model = model;
-  this.message = 'Cast to ' + this.kind + ' failed for value ' +
-    this.stringValue + ' at path "' + this.path + '"' + ' for model "' +
-    model.modelName + '"';
+  this.message = this.formatMessage(model);
+};
+
+/*!
+ * ignore
+ */
+
+CastError.prototype.formatMessage = function(model) {
+  if (this.messageFormat != null) {
+    let ret = this.messageFormat.
+      replace('{KIND}', this.kind).
+      replace('{VALUE}', this.stringValue).
+      replace('{PATH}', this.path);
+    if (model != null) {
+      ret = ret.replace('{MODEL}', model.modelName);
+    }
+
+    return ret;
+  } else {
+    let ret = 'Cast to ' + this.kind + ' failed for value ' +
+      this.stringValue + ' at path "' + this.path + '"';
+    if (model != null) {
+      ret += ' for model "' + model.modelName + '"';
+    }
+
+    return ret;
+  }
 };
 
 /*!
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 0a7236db8fe..898738d533f 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -49,6 +49,37 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'type', opts);
 
 Object.defineProperty(SchemaTypeOptions.prototype, 'validate', opts);
 
+/**
+ * Allows overriding casting logic for this individual path. If a string, the
+ * given string overwrites Mongoose's default cast error message.
+ *
+ * ####Example:
+ *
+ *     const schema = new Schema({
+ *       num: {
+ *         type: Number,
+ *         cast: '{VALUE} is not a valid number'
+ *       }
+ *     });
+ *
+ *     // Throws 'CastError: "bad" is not a valid number'
+ *     schema.path('num').cast('bad');
+ *
+ *     const Model = mongoose.model('Test', schema);
+ *     const doc = new Model({ num: 'fail' });
+ *     const err = doc.validateSync();
+ *
+ *     err.errors['num']; // 'CastError: "fail" is not a valid number'
+ *
+ * @api public
+ * @property cast
+ * @memberOf SchemaTypeOptions
+ * @type String
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'cast', opts);
+
 /**
  * If true, attach a required validator to this path, which ensures this path
  * path cannot be set to a nullish value. If a function, Mongoose calls the
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 27be2b16b16..46bb68eca22 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -226,7 +226,7 @@ SingleNestedPath.prototype.castForQuery = function($conditional, val) {
   } catch (error) {
     // Make sure we always wrap in a CastError (gh-6803)
     if (!(error instanceof CastError)) {
-      throw new CastError('Embedded', val, this.path, error);
+      throw new CastError('Embedded', val, this.path, error, this);
     }
     throw error;
   }
diff --git a/lib/schema/array.js b/lib/schema/array.js
index ba1e5d475b7..4e699ec3d81 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -291,7 +291,7 @@ SchemaArray.prototype.cast = function(value, doc, init) {
         }
       } catch (e) {
         // rethrow
-        throw new CastError('[' + e.kind + ']', util.inspect(value), this.path, e);
+        throw new CastError('[' + e.kind + ']', util.inspect(value), this.path, e, this);
       }
     }
 
@@ -307,7 +307,7 @@ SchemaArray.prototype.cast = function(value, doc, init) {
     return this.cast([value], doc, init);
   }
 
-  throw new CastError('Array', util.inspect(value), this.path);
+  throw new CastError('Array', util.inspect(value), this.path, null, this);
 };
 
 /*!
diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 080cd24f39a..13d796c45f8 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -171,7 +171,7 @@ SchemaBoolean.prototype.cast = function(value) {
   try {
     return castBoolean(value);
   } catch (error) {
-    throw new CastError('Boolean', value, this.path);
+    throw new CastError('Boolean', value, this.path, error, this);
   }
 };
 
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 69ccdaa8af5..91edf2aaf71 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -119,7 +119,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
     if (Buffer.isBuffer(value)) {
       return value;
     } else if (!utils.isObject(value)) {
-      throw new CastError('buffer', value, this.path);
+      throw new CastError('buffer', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -155,7 +155,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
   if (value instanceof Binary) {
     ret = new MongooseBuffer(value.value(true), [this.path, doc]);
     if (typeof value.sub_type !== 'number') {
-      throw new CastError('buffer', value, this.path);
+      throw new CastError('buffer', value, this.path, null, this);
     }
     ret._subtype = value.sub_type;
     return ret;
@@ -181,7 +181,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
     return ret;
   }
 
-  throw new CastError('buffer', value, this.path);
+  throw new CastError('buffer', value, this.path, null, this);
 };
 
 /**
diff --git a/lib/schema/date.js b/lib/schema/date.js
index 6a0e9aae46b..3c9b9146f33 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -311,7 +311,7 @@ SchemaDate.prototype.cast = function(value) {
   try {
     return castDate(value);
   } catch (error) {
-    throw new CastError('date', value, this.path);
+    throw new CastError('date', value, this.path, error, this);
   }
 };
 
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index 3c9c2bdf2f5..0978d47b267 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -157,7 +157,7 @@ Decimal128.prototype.cast = function(value, doc, init) {
     if (value instanceof Decimal128Type) {
       return value;
     } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('Decimal128', value, this.path);
+      throw new CastError('Decimal128', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -185,7 +185,7 @@ Decimal128.prototype.cast = function(value, doc, init) {
   try {
     return castDecimal128(value);
   } catch (error) {
-    throw new CastError('Decimal128', value, this.path);
+    throw new CastError('Decimal128', value, this.path, error, this);
   }
 };
 
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index c7c179e830b..28d4a4b1a82 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -355,7 +355,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
 
   if (!Array.isArray(value)) {
     if (!init && !DocumentArrayPath.options.castNonArrays) {
-      throw new CastError('DocumentArray', util.inspect(value), this.path);
+      throw new CastError('DocumentArray', util.inspect(value), this.path, null, this);
     }
     // gh-2442 mark whole array as modified if we're initializing a doc from
     // the db and the path isn't an array in the document
@@ -430,7 +430,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
           } catch (error) {
             const valueInErrorMessage = util.inspect(value[i]);
             throw new CastError('embedded', valueInErrorMessage,
-              value[arrayPathSymbol], error);
+              value[arrayPathSymbol], error, this);
           }
         }
       }
diff --git a/lib/schema/number.js b/lib/schema/number.js
index a5d6bcc9195..e32ae2b4237 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -334,7 +334,7 @@ SchemaNumber.prototype.cast = function(value, doc, init) {
     if (typeof value === 'number') {
       return value;
     } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('number', value, this.path);
+      throw new CastError('number', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -358,7 +358,7 @@ SchemaNumber.prototype.cast = function(value, doc, init) {
   try {
     return castNumber(val);
   } catch (err) {
-    throw new CastError('number', val, this.path);
+    throw new CastError('number', val, this.path, err, this);
   }
 };
 
@@ -406,7 +406,7 @@ SchemaNumber.prototype.castForQuery = function($conditional, val) {
   if (arguments.length === 2) {
     handler = this.$conditionalHandlers[$conditional];
     if (!handler) {
-      throw new CastError('Can\'t use ' + $conditional + ' with Number.');
+      throw new CastError('number', val, this.path, null, this);
     }
     return handler.call(this, val);
   }
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index ae20493159b..761ebd1df4a 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -215,7 +215,7 @@ ObjectId.prototype.cast = function(value, doc, init) {
     } else if ((value.constructor.name || '').toLowerCase() === 'objectid') {
       return new oid(value.toHexString());
     } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('ObjectId', value, this.path);
+      throw new CastError('ObjectId', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -243,7 +243,7 @@ ObjectId.prototype.cast = function(value, doc, init) {
   try {
     return castObjectId(value);
   } catch (error) {
-    throw new CastError('ObjectId', value, this.path);
+    throw new CastError('ObjectId', value, this.path, error, this);
   }
 };
 
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 645c4c3571e..d25912f98e5 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -537,7 +537,7 @@ SchemaString.prototype.cast = function(value, doc, init) {
     if (typeof value === 'string') {
       return value;
     } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('string', value, this.path);
+      throw new CastError('string', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -557,7 +557,7 @@ SchemaString.prototype.cast = function(value, doc, init) {
   try {
     return castString(value);
   } catch (error) {
-    throw new CastError('string', value, this.path);
+    throw new CastError('string', value, this.path, null, this);
   }
 };
 
diff --git a/lib/schematype.js b/lib/schematype.js
index 5b3e918036b..96c26735a54 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -56,6 +56,9 @@ function SchemaType(path, options, instance) {
 
   const keys = Object.keys(this.options);
   for (const prop of keys) {
+    if (prop === 'cast') {
+      continue;
+    }
     if (utils.hasUserDefinedProperty(this.options, prop) && typeof this[prop] === 'function') {
       // { unique: true, index: true }
       if (prop === 'index' && this._index) {
diff --git a/test/schema.test.js b/test/schema.test.js
index dccbe8cc0d1..e4a7fea14ee 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2280,4 +2280,63 @@ describe('schema', function() {
       assert.ok(!newSchema.path('age'));
     });
   });
+
+  describe('path-level custom cast (gh-8300)', function() {
+    it('with numbers', function() {
+      const schema = Schema({
+        num: {
+          type: Number,
+          cast: '{VALUE} is not a number'
+        }
+      });
+
+      let threw = false;
+      try {
+        schema.path('num').cast('horseradish');
+      } catch (err) {
+        threw = true;
+        assert.equal(err.name, 'CastError');
+        assert.equal(err.message, '"horseradish" is not a number');
+      }
+      assert.ok(threw);
+    });
+
+    it('with objectids', function() {
+      const schema = Schema({
+        userId: {
+          type: mongoose.ObjectId,
+          cast: 'Invalid user ID'
+        }
+      });
+
+      let threw = false;
+      try {
+        schema.path('userId').cast('foo');
+      } catch (err) {
+        threw = true;
+        assert.equal(err.name, 'CastError');
+        assert.equal(err.message, 'Invalid user ID');
+      }
+      assert.ok(threw);
+    });
+
+    it('with boolean', function() {
+      const schema = Schema({
+        vote: {
+          type: Boolean,
+          cast: '{VALUE} is invalid at path {PATH}'
+        }
+      });
+
+      let threw = false;
+      try {
+        schema.path('vote').cast('nay');
+      } catch (err) {
+        threw = true;
+        assert.equal(err.name, 'CastError');
+        assert.equal(err.message, '"nay" is invalid at path vote');
+      }
+      assert.ok(threw);
+    });
+  });
 });

From 1eaefc838d7321f7ced953f4bc5a40dbe02f6924 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 08:14:00 -0500
Subject: [PATCH 0242/2348] chore(connection): set driverInfo option

---
 lib/connection.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index ff75f118786..3fe42ff9c2c 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -13,6 +13,7 @@ const PromiseProvider = require('./promise_provider');
 const applyPlugins = require('./helpers/schema/applyPlugins');
 const get = require('./helpers/get');
 const mongodb = require('mongodb');
+const pkg = require('../package.json');
 const utils = require('./utils');
 
 const parseConnectionString = require('mongodb/lib/core').parseConnectionString;
@@ -620,6 +621,12 @@ Connection.prototype.openUri = function(uri, options, callback) {
       options.useUnifiedTopology = false;
     }
   }
+  if (!utils.hasUserDefinedProperty(options, 'driverInfo')) {
+    options.driverInfo = {
+      name: 'Mongoose',
+      version: pkg.version
+    };
+  }
 
   const parsePromise = new Promise((resolve, reject) => {
     parseConnectionString(uri, options, (err, parsed) => {

From 4a212e18b367263cd708524fcb7c2810b78e5b42 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 10:14:58 -0500
Subject: [PATCH 0243/2348] feat: capture original stack trace when reporting
 server selection timeout error

Fix #8259
---
 lib/drivers/node-mongodb-native/collection.js |  2 +-
 lib/error/timeout.js                          | 35 ++++++++
 lib/model.js                                  | 84 +++++++++++++------
 lib/query.js                                  |  8 +-
 4 files changed, 100 insertions(+), 29 deletions(-)
 create mode 100644 lib/error/timeout.js

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index bfe817a6692..1ba812a19ae 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -116,7 +116,7 @@ const syncCollectionMethods = { watch: true };
 
 function iter(i) {
   NativeCollection.prototype[i] = function() {
-    const collection = this.collection;
+    const collection = this.collection || this.conn.client.db().collection(this.name);
     const args = Array.from(arguments);
     const _this = this;
     const debug = get(_this, 'conn.base.options.debug');
diff --git a/lib/error/timeout.js b/lib/error/timeout.js
new file mode 100644
index 00000000000..f35f08f55e1
--- /dev/null
+++ b/lib/error/timeout.js
@@ -0,0 +1,35 @@
+/*!
+ * Module dependencies.
+ */
+
+'use strict';
+
+const MongooseError = require('./mongooseError');
+
+/**
+ * MongooseTimeoutError constructor
+ *
+ * @param {String} type
+ * @param {String} value
+ * @inherits MongooseError
+ * @api private
+ */
+
+function MongooseTimeoutError(message) {
+  MongooseError.call(this, message);
+  this.name = 'MongooseTimeoutError';
+  if (Error.captureStackTrace) {
+    Error.captureStackTrace(this);
+  } else {
+    this.stack = new Error().stack;
+  }
+}
+
+/*!
+ * Inherits from MongooseError.
+ */
+
+MongooseTimeoutError.prototype = Object.create(MongooseError.prototype);
+MongooseTimeoutError.prototype.constructor = MongooseError;
+
+module.exports = MongooseTimeoutError;
diff --git a/lib/model.js b/lib/model.js
index d66dd42a413..3b8b80c5394 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -18,6 +18,7 @@ const Query = require('./query');
 const RemoveOptions = require('./options/removeOptions');
 const SaveOptions = require('./options/saveOptions');
 const Schema = require('./schema');
+const TimeoutError = require('./error/timeout');
 const ValidationError = require('./error/validation');
 const VersionError = require('./error/version');
 const ParallelSaveError = require('./error/parallelSave');
@@ -455,7 +456,9 @@ Model.prototype.save = function(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
+  return utils.promiseOrCallback(fn, cb => {
+    cb = this.constructor.$wrapCallback(cb);
+
     if (parallelSave) {
       this.$__handleReject(parallelSave);
       return cb(parallelSave);
@@ -474,7 +477,7 @@ Model.prototype.save = function(options, fn) {
       }
       cb(null, this);
     });
-  }), this.constructor.events);
+  }, this.constructor.events);
 };
 
 /*!
@@ -899,9 +902,10 @@ Model.prototype.remove = function remove(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
+  return utils.promiseOrCallback(fn, cb => {
+    cb = this.constructor.$wrapCallback(cb);
     this.$__remove(options, cb);
-  }), this.constructor.events);
+  }, this.constructor.events);
 };
 
 /**
@@ -934,9 +938,10 @@ Model.prototype.deleteOne = function deleteOne(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return utils.promiseOrCallback(fn, this.constructor.$wrapCallback(cb => {
+  return utils.promiseOrCallback(fn, cb => {
+    cb = this.constructor.$wrapCallback(cb);
     this.$__deleteOne(options, cb);
-  }), this.constructor.events);
+  }, this.constructor.events);
 };
 
 /*!
@@ -1280,7 +1285,9 @@ Model.createCollection = function createCollection(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
+
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
       if (error) {
         return cb(error);
@@ -1288,7 +1295,7 @@ Model.createCollection = function createCollection(options, callback) {
       this.collection = this.db.collection(this.collection.collectionName, options);
       cb(null, this.collection);
     }));
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -1319,7 +1326,9 @@ Model.syncIndexes = function syncIndexes(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
+
     this.createCollection(err => {
       if (err) {
         return cb(err);
@@ -1336,7 +1345,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
         });
       });
     });
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -1466,14 +1475,16 @@ Model.listIndexes = function init(callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
+
     // Buffering
     if (this.collection.buffer) {
       this.collection.addQueue(_listIndexes, [cb]);
     } else {
       _listIndexes(cb);
     }
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -1515,14 +1526,16 @@ Model.ensureIndexes = function ensureIndexes(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
+
     _ensureIndexes(this, options || {}, error => {
       if (error) {
         return cb(error);
       }
       cb(null);
     });
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -3011,7 +3024,8 @@ Model.create = function create(doc, options, callback) {
     }
   }
 
-  return utils.promiseOrCallback(cb, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(cb, cb => {
+    cb = this.$wrapCallback(cb);
     if (args.length === 0) {
       return cb(null);
     }
@@ -3083,7 +3097,7 @@ Model.create = function create(doc, options, callback) {
         }
       });
     });
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -3414,7 +3428,8 @@ Model.bulkWrite = function(ops, options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
     each(validations, (fn, cb) => fn(cb), error => {
       if (error) {
         return cb(error);
@@ -3428,7 +3443,7 @@ Model.bulkWrite = function(ops, options, callback) {
         cb(null, res);
       });
     });
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -3778,7 +3793,9 @@ Model.mapReduce = function mapReduce(o, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
+
     if (!Model.mapReduce.schema) {
       const opts = {noId: true, noVirtualId: true, strict: false};
       Model.mapReduce.schema = new Schema({}, opts);
@@ -3815,7 +3832,7 @@ Model.mapReduce = function mapReduce(o, callback) {
 
       cb(null, res);
     });
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -4027,7 +4044,8 @@ Model.geoSearch = function(conditions, options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
     let error;
     if (conditions === undefined || !utils.isObject(conditions)) {
       error = new MongooseError('Must pass conditions to geoSearch');
@@ -4072,7 +4090,7 @@ Model.geoSearch = function(conditions, options, callback) {
         res.results[i].init(temp, {}, init);
       }
     });
-  }), this.events);
+  }, this.events);
 };
 
 /**
@@ -4161,9 +4179,10 @@ Model.populate = function(docs, paths, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.$wrapCallback(cb => {
+  return utils.promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
     _populate(_this, docs, paths, cache, cb);
-  }), this.events);
+  }, this.events);
 };
 
 /*!
@@ -4722,6 +4741,7 @@ Model.$handleCallbackError = function(callback) {
   if (typeof callback !== 'function') {
     throw new MongooseError('Callback must be a function, got ' + callback);
   }
+
   const _this = this;
   return function() {
     try {
@@ -4732,8 +4752,22 @@ Model.$handleCallbackError = function(callback) {
   };
 };
 
+/*!
+ * ignore
+ */
+
 Model.$wrapCallback = function(callback) {
-  return callback;
+  const timeout = new TimeoutError();
+
+  return function(err) {
+    if (err != null && err.name === 'MongoTimeoutError') {
+      arguments[0] = timeout;
+      timeout.message = err.message;
+      Object.assign(timeout, err);
+    }
+
+    return callback.apply(null, arguments);
+  };
 };
 
 /**
diff --git a/lib/query.js b/lib/query.js
index 8e3cc5f97a4..263be14b856 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4350,14 +4350,16 @@ Query.prototype.exec = function exec(op, callback) {
 
   callback = this.model.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, this.model.$wrapCallback((cb) => {
+  return utils.promiseOrCallback(callback, (cb) => {
+    cb = this.model.$wrapCallback(cb);
+
     if (!_this.op) {
       cb();
       return;
     }
 
     this._hooks.execPre('exec', this, [], (error) => {
-      if (error) {
+      if (error != null) {
         return cb(error);
       }
       this[this.op].call(this, (error, res) => {
@@ -4374,7 +4376,7 @@ Query.prototype.exec = function exec(op, callback) {
         });
       });
     });
-  }), this.model.events);
+  }, this.model.events);
 };
 
 /*!

From 253e054834d03ff282f4b4848d12ec734c8551dd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 10:53:59 -0500
Subject: [PATCH 0244/2348] test(schematype): repro #8360

---
 test/schema.type.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/schema.type.test.js b/test/schema.type.test.js
index b1c37594576..d217615f3ce 100644
--- a/test/schema.type.test.js
+++ b/test/schema.type.test.js
@@ -87,4 +87,17 @@ describe('schematype', function() {
       assert.ifError(err);
     });
   });
+
+  it('handles function as positional message arg (gh-8360)', function() {
+    const schema = Schema({
+      name: {
+        type: String,
+        validate: [() => false, err => `${err.path} is invalid!`]
+      }
+    });
+
+    const err = schema.path('name').doValidateSync('test');
+    assert.equal(err.name, 'ValidatorError');
+    assert.equal(err.message, 'name is invalid!');
+  });
 });

From 491b9cc42ccfcbadb73fe9803117e568ae3a8d32 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 11:08:04 -0500
Subject: [PATCH 0245/2348] fix(schematype): handle passing `message` function
 to `SchemaType#validate()` as positional arg

Fix #8360
---
 lib/schematype.js | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index 5b3e918036b..7d53d522fd4 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -676,7 +676,10 @@ SchemaType.prototype.get = function(fn) {
 SchemaType.prototype.validate = function(obj, message, type) {
   if (typeof obj === 'function' || obj && utils.getFunctionName(obj.constructor) === 'RegExp') {
     let properties;
-    if (message instanceof Object && !type) {
+    if (typeof message === 'function') {
+      properties = { validator: obj, message: message };
+      properties.type = type || 'user defined';
+    } else if (message instanceof Object && !type) {
       properties = utils.clone(message);
       if (!properties.message) {
         properties.message = properties.msg;
@@ -684,13 +687,13 @@ SchemaType.prototype.validate = function(obj, message, type) {
       properties.validator = obj;
       properties.type = properties.type || 'user defined';
     } else {
-      if (!message) {
+      if (message == null) {
         message = MongooseError.messages.general.default;
       }
       if (!type) {
         type = 'user defined';
       }
-      properties = {message: message, type: type, validator: obj};
+      properties = { message: message, type: type, validator: obj };
     }
 
     if (properties.isAsync) {

From d4a7ef3f23edeeab9db124218990999c937c880f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 11:37:43 -0500
Subject: [PATCH 0246/2348] test(cursor): repro #8352

---
 test/files/{sample.js => sample.esm}  |  0
 test/helpers/cursor.eachAsync.test.js | 32 +++++++++++++++++++++++++++
 test/mocha.opts                       |  3 ++-
 3 files changed, 34 insertions(+), 1 deletion(-)
 rename test/files/{sample.js => sample.esm} (100%)

diff --git a/test/files/sample.js b/test/files/sample.esm
similarity index 100%
rename from test/files/sample.js
rename to test/files/sample.esm
diff --git a/test/helpers/cursor.eachAsync.test.js b/test/helpers/cursor.eachAsync.test.js
index 14c4e1f5847..b7d847b055a 100644
--- a/test/helpers/cursor.eachAsync.test.js
+++ b/test/helpers/cursor.eachAsync.test.js
@@ -27,4 +27,36 @@ describe('eachAsync()', function() {
     return eachAsync(next, () => Promise.resolve(++processed), { parallel: 8 }).
       then(() => assert.equal(processed, max));
   });
+
+  it('waits until the end before resolving the promise (gh-8352)', function() {
+    const max = 2;
+    let numCalled = 0;
+    let numDone = 0;
+    function next(cb) {
+      setImmediate(() => {
+        if (++numCalled > max) {
+          return cb(null, null);
+        }
+        cb(null, { num: numCalled });
+      });
+    }
+
+    function fn() {
+      return new Promise(resolve => {
+        setTimeout(() => {
+          ++numDone;
+          resolve();
+        }, 100);
+      });
+    }
+
+    return eachAsync(next, fn, { parallel: 3 }).
+      then(() => assert.equal(numDone, max)).
+      then(() => {
+        numCalled = 0;
+        numDone = 0;
+      }).
+      then(() => eachAsync(next, fn, { parallel: 2 })).
+      then(() => assert.equal(numDone, max));
+  });
 });
\ No newline at end of file
diff --git a/test/mocha.opts b/test/mocha.opts
index a35a923698e..5d74b8a768e 100644
--- a/test/mocha.opts
+++ b/test/mocha.opts
@@ -1,2 +1,3 @@
 --reporter dot
---ui bdd
\ No newline at end of file
+--ui bdd
+--recursive
\ No newline at end of file

From f06d1c75acd9e62c96829c105212854b507a93a9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 12:45:14 -0500
Subject: [PATCH 0247/2348] fix(cursor): wait until all `eachAsync()` functions
 finish before resolving the promise

Fix #8352
---
 lib/helpers/cursor/eachAsync.js | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 95a38dbf93a..029f203c9eb 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -35,8 +35,9 @@ module.exports = function eachAsync(next, fn, options, callback) {
     }
   };
 
-  const iterate = function(callback) {
+  const iterate = function(finalCallback) {
     let drained = false;
+    let handleResultsInProgress = 0;
 
     let error = null;
     for (let i = 0; i < parallel; ++i) {
@@ -49,26 +50,33 @@ module.exports = function eachAsync(next, fn, options, callback) {
       }
 
       next(function(err, doc) {
-        if (drained || error) {
+        if (drained || error != null) {
           return done();
         }
         if (err != null) {
           error = err;
-          callback(err);
+          finalCallback(err);
           return done();
         }
         if (doc == null) {
           drained = true;
-          callback(null);
+          if (handleResultsInProgress <= 0) {
+            finalCallback(null);
+          }
           return done();
         }
 
         done();
 
+        ++handleResultsInProgress;
         handleNextResult(doc, function(err) {
+          --handleResultsInProgress;
           if (err != null) {
             error = err;
-            return callback(err);
+            return finalCallback(err);
+          }
+          if (drained && handleResultsInProgress <= 0) {
+            return finalCallback(null);
           }
 
           setTimeout(() => enqueue(fetch), 0);

From ae66e46b2dbd639044a96e28b4b255d2217c52fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Dec 2019 12:53:27 -0500
Subject: [PATCH 0248/2348] chore: add subdirs.test.js that requires in
 subdirectories

Re: #8322
---
 test/files/{sample.esm => sample.js} |  0
 test/mocha.opts                      |  3 +--
 test/subdirs.test.js                 | 15 +++++++++++++++
 3 files changed, 16 insertions(+), 2 deletions(-)
 rename test/files/{sample.esm => sample.js} (100%)
 create mode 100644 test/subdirs.test.js

diff --git a/test/files/sample.esm b/test/files/sample.js
similarity index 100%
rename from test/files/sample.esm
rename to test/files/sample.js
diff --git a/test/mocha.opts b/test/mocha.opts
index 5d74b8a768e..a35a923698e 100644
--- a/test/mocha.opts
+++ b/test/mocha.opts
@@ -1,3 +1,2 @@
 --reporter dot
---ui bdd
---recursive
\ No newline at end of file
+--ui bdd
\ No newline at end of file
diff --git a/test/subdirs.test.js b/test/subdirs.test.js
new file mode 100644
index 00000000000..2c051195b32
--- /dev/null
+++ b/test/subdirs.test.js
@@ -0,0 +1,15 @@
+'use strict';
+
+const fs = require('fs');
+
+let files = fs.readdirSync(`${__dirname}/docs`);
+
+for (const file of files) {
+  require(`./docs/${file}`);
+}
+
+files = fs.readdirSync(`${__dirname}/helpers`);
+
+for (const file of files) {
+  require(`./helpers/${file}`);
+}
\ No newline at end of file

From 5cdfa4af6de1db8089355fdb128bc88500333afb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Dec 2019 14:58:18 -0500
Subject: [PATCH 0249/2348] test(update): repro #8378

---
 test/model.findOneAndUpdate.test.js | 32 +++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index efa5091ba73..e1f4ef0b3c6 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -2404,4 +2404,36 @@ describe('model: findOneAndUpdate:', function() {
       assert.equal(res.name, 'test2');
     });
   });
+
+  it('updating embedded discriminator with discriminator key in update (gh-8378)', function() {
+    const shapeSchema = Schema({ name: String }, { discriminatorKey: 'kind' });
+    const schema = Schema({ shape: shapeSchema });
+
+    schema.path('shape').discriminator('gh8378_Circle',
+      Schema({ radius: String, color: String }));
+    schema.path('shape').discriminator('gh8378_Square',
+      Schema({ side: Number, color: String }));
+
+    const MyModel = db.model('gh8378_Shape', schema);
+
+    return co(function*() {
+      let doc = yield MyModel.create({
+        shape: {
+          kind: 'gh8378_Circle',
+          name: 'before',
+          radius: 5,
+          color: 'red'
+        }
+      });
+
+      doc = yield MyModel.findByIdAndUpdate(doc._id, {
+        'shape.kind': 'gh8378_Circle',
+        'shape.name': 'after',
+        'shape.radius': 10
+      }, { new: true });
+
+      assert.equal(doc.shape.name, 'after');
+      assert.equal(doc.shape.radius, 10);
+    });
+  });
 });

From 4df0a3cb2f28ead7f754e18925eacc2abc4b7288 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Dec 2019 14:58:34 -0500
Subject: [PATCH 0250/2348] fix(update): handle embedded discriminator paths
 when discriminator key is defined in the update

Fix #8378
---
 lib/helpers/query/castUpdate.js                   | 3 ++-
 lib/helpers/query/getEmbeddedDiscriminatorPath.js | 4 ++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 37a53b5a7e6..231da434e17 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -249,7 +249,8 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
 
       let pathDetails = schema._getPathType(checkPath);
 
-      // If no schema type, check for embedded discriminators
+      // If no schema type, check for embedded discriminators because the
+      // filter or update may imply an embedded discriminator type. See #8378
       if (schematype == null) {
         const _res = getEmbeddedDiscriminatorPath(schema, obj, filter, checkPath);
         if (_res.schematype != null) {
diff --git a/lib/helpers/query/getEmbeddedDiscriminatorPath.js b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
index 8214158377b..ff297ace6ff 100644
--- a/lib/helpers/query/getEmbeddedDiscriminatorPath.js
+++ b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
@@ -45,6 +45,10 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
         discriminatorKey = filter[wrapperPath].$elemMatch[key];
       }
 
+      if (discriminatorValuePath in update) {
+        discriminatorKey = update[discriminatorValuePath];
+      }
+
       if (discriminatorKey == null || discriminators[discriminatorKey] == null) {
         continue;
       }

From faabdbb6dbc83c6540af8b7e6ba82ddea74f283e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Dec 2019 16:25:26 -0500
Subject: [PATCH 0251/2348] docs(schema): clarify that `uppercase`,
 `lowercase`, and `trim` options for SchemaString don't affect RegExp queries

Fix #8333
---
 lib/schema/string.js | 35 +++++++++++++++++++++++++++++------
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/lib/schema/string.js b/lib/schema/string.js
index 645c4c3571e..ff8a33a84d4 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -232,6 +232,14 @@ SchemaString.prototype.enum = function() {
  *     console.log(m.email) // someemail@example.com
  *     M.find({ email: 'SomeEmail@example.com' }); // Queries by 'someemail@example.com'
  *
+ * Note that `lowercase` does **not** affect regular expression queries:
+ *
+ * ####Example:
+ *     // Still queries for documents whose `email` matches the regular
+ *     // expression /SomeEmail/. Mongoose does **not** convert the RegExp
+ *     // to lowercase.
+ *     M.find({ email: /SomeEmail/ });
+ *
  * @api public
  * @return {SchemaType} this
  */
@@ -262,6 +270,12 @@ SchemaString.prototype.lowercase = function(shouldApply) {
  *     console.log(m.caps) // AN EXAMPLE
  *     M.find({ caps: 'an example' }) // Matches documents where caps = 'AN EXAMPLE'
  *
+ * Note that `uppercase` does **not** affect regular expression queries:
+ *
+ * ####Example:
+ *     // Mongoose does **not** convert the RegExp to uppercase.
+ *     M.find({ email: /an example/ });
+ *
  * @api public
  * @return {SchemaType} this
  */
@@ -288,12 +302,21 @@ SchemaString.prototype.uppercase = function(shouldApply) {
  *
  * ####Example:
  *
- *     var s = new Schema({ name: { type: String, trim: true }})
- *     var M = db.model('M', s)
- *     var string = ' some name '
- *     console.log(string.length) // 11
- *     var m = new M({ name: string })
- *     console.log(m.name.length) // 9
+ *     var s = new Schema({ name: { type: String, trim: true }});
+ *     var M = db.model('M', s);
+ *     var string = ' some name ';
+ *     console.log(string.length); // 11
+ *     var m = new M({ name: string });
+ *     console.log(m.name.length); // 9
+ *
+ *     // Equivalent to `findOne({ name: string.trim() })`
+ *     M.findOne({ name: string });
+ *
+ * Note that `trim` does **not** affect regular expression queries:
+ *
+ * ####Example:
+ *     // Mongoose does **not** trim whitespace from the RegExp.
+ *     M.find({ name: / some name / });
  *
  * @api public
  * @return {SchemaType} this

From 127d687d7ab796119b474395e3e8bab0a6dd0c2d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Dec 2019 16:27:48 -0500
Subject: [PATCH 0252/2348] chore: remove debug code thats causing tests to
 break

---
 lib/drivers/node-mongodb-native/collection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 1ba812a19ae..bfe817a6692 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -116,7 +116,7 @@ const syncCollectionMethods = { watch: true };
 
 function iter(i) {
   NativeCollection.prototype[i] = function() {
-    const collection = this.collection || this.conn.client.db().collection(this.name);
+    const collection = this.collection;
     const args = Array.from(arguments);
     const _this = this;
     const debug = get(_this, 'conn.base.options.debug');

From 6ec6980a60d9cb96c7002445ecd08dcf8c337ef3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Dec 2019 16:22:36 -0500
Subject: [PATCH 0253/2348] test: make parallelLimit test more robust to timing
 issues

Fix #8386
---
 test/parallelLimit.test.js | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/test/parallelLimit.test.js b/test/parallelLimit.test.js
index af532d7b342..4130006d00a 100644
--- a/test/parallelLimit.test.js
+++ b/test/parallelLimit.test.js
@@ -13,30 +13,36 @@ describe('parallelLimit', function() {
   });
 
   it('executes functions in parallel', function(done) {
-    let called = 0;
+    let started = 0;
+    let finished = 0;
     const fns = [
       cb => {
+        ++started;
         setTimeout(() => {
-          ++called;
+          ++finished;
           setTimeout(cb, 0);
         }, 100);
       },
       cb => {
+        ++started;
         setTimeout(() => {
-          ++called;
+          ++finished;
           setTimeout(cb, 0);
         }, 100);
       },
       cb => {
-        assert.equal(called, 2);
-        ++called;
-        setTimeout(cb, 100);
+        assert.equal(started, 2);
+        assert.ok(finished > 0);
+        ++started;
+        ++finished;
+        setTimeout(cb, 0);
       }
     ];
 
     parallelLimit(fns, 2, (err) => {
       assert.ifError(err);
-      assert.equal(called, 3);
+      assert.equal(started, 3);
+      assert.equal(finished, 3);
       done();
     });
   });

From 7575882fb732c0ad2c15a00a34c19ae6c670a207 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Dec 2019 17:17:06 -0500
Subject: [PATCH 0254/2348] chore: release 5.7.14

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 3351904aefa..c5698814cca 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.7.14 / 2019-12-06
+===================
+ * fix(cursor): wait until all `eachAsync()` functions finish before resolving the promise #8352
+ * fix(update): handle embedded discriminator paths when discriminator key is defined in the update #8378
+ * fix(schematype): handle passing `message` function to `SchemaType#validate()` as positional arg #8360
+ * fix(map): handle cloning a schema that has a map of subdocuments #8357
+ * docs(schema): clarify that `uppercase`, `lowercase`, and `trim` options for SchemaString don't affect RegExp queries #8333
+
 5.7.13 / 2019-11-29
 ===================
  * fix: upgrade mongodb driver -> 3.3.5 #8383
diff --git a/package.json b/package.json
index cce6a944c8d..a2c84348c03 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.14-pre",
+  "version": "5.7.14",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From edd82775288766d800febdfc0fcf9b13f0d34fc1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Dec 2019 12:25:03 -0500
Subject: [PATCH 0255/2348] chore: now working on 5.7.15

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index a2c84348c03..c81226b6217 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.14",
+  "version": "5.7.15-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 8a7aefed64b361a063410dc6048064d9fd872051 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Dec 2019 14:35:35 -0500
Subject: [PATCH 0256/2348] docs(model+query): add `session` option to docs for
 findOneAndX() methods

Fix #8396
---
 lib/model.js | 5 +++++
 lib/query.js | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index f88c8f4edbb..cd413bbd2d1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2408,6 +2408,7 @@ Model.$where = function $where() {
  * @param {Object} [update]
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Function} [callback]
@@ -2634,6 +2635,7 @@ Model.findByIdAndUpdate = function(id, update, options, callback) {
  * @param {Object} conditions
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Function} [callback]
  * @return {Query}
  * @api public
@@ -2739,6 +2741,7 @@ Model.findByIdAndDelete = function(id, options, callback) {
  * @param {Object} [replacement] Replace with this document
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Function} [callback]
@@ -2829,6 +2832,7 @@ Model.findOneAndReplace = function(filter, replacement, options, callback) {
  *
  * @param {Object} conditions
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Function} [callback]
  * @return {Query}
@@ -2894,6 +2898,7 @@ Model.findOneAndRemove = function(conditions, options, callback) {
  * @param {Object|Number|String} id value of `_id` to query by
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndRemove #model_Model.findOneAndRemove
diff --git a/lib/query.js b/lib/query.js
index bb501e5c5ae..222d210fe24 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2915,6 +2915,7 @@ function prepareDiscriminatorCriteria(query) {
  * @param {Object} [options]
  * @param {Boolean} [options.rawResult] if true, returns the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean} [options.multipleCastError] by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
@@ -3039,6 +3040,7 @@ Query.prototype._findOneAndUpdate = wrapThunk(function(callback) {
  * @param {Object} [conditions]
  * @param {Object} [options]
  * @param {Boolean} [options.rawResult] if true, returns the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Function} [callback] optional params are (error, document)
  * @return {Query} this
@@ -3123,6 +3125,7 @@ Query.prototype.findOneAndRemove = function(conditions, options, callback) {
  * @param {Object} [conditions]
  * @param {Object} [options]
  * @param {Boolean} [options.rawResult] if true, returns the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Function} [callback] optional params are (error, document)
  * @return {Query} this
@@ -3241,6 +3244,7 @@ Query.prototype._findOneAndDelete = wrapThunk(function(callback) {
  * @param {Object} [replacement]
  * @param {Object} [options]
  * @param {Boolean} [options.rawResult] if true, returns the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify)
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.

From 9ce13758f73ba24627dc84d178f8550dec14b45f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Dec 2019 14:45:13 -0500
Subject: [PATCH 0257/2348] chore: release 5.8.0

---
 History.md   | 22 ++++++++++++++++++++++
 package.json |  2 +-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c5698814cca..c1340c0d132 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,25 @@
+5.8.0 / 2019-12-09
+==================
+ * feat: wrap server selection timeout errors in `MongooseTimeoutError` to retain original stack trace #8259
+ * feat(model): add `Model.validate()` function that validates a POJO against the model's schema #7587
+ * feat(schema): add `Schema#pick()` function to create a new schema with a picked subset of the original schema's paths #8207
+ * feat(schema): add ability to change CastError message using `cast` option to SchemaType #8300
+ * feat(schema): group indexes defined in schema path with the same name #6499
+ * fix(model): build all indexes even if one index fails #8185 [unusualbob](https://github.com/unusualbob)
+ * feat(browser): pre-compile mongoose/browser #8350 [captaincaius](https://github.com/captaincaius)
+ * fix(connection): throw error when setting unsupported option #8335 #6899 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(schema): support `enum` validator for number type #8139
+ * feat(update): allow using MongoDB 4.2 update aggregation pipelines, with no Mongoose casting #8225
+ * fix(update): make update validators run on all subpaths when setting a nested path, even omitted subpaths #3587
+ * feat(schema): support setting `_id` as an option to single nested schema paths #8137
+ * feat(query): add Query#mongooseOptions() function #8296
+ * feat(array): make `MongooseArray#push()` support using `$position` #4322
+ * feat(schema): make pojo paths optionally become subdoc instead of Mixed #8228 [captaincaius](https://github.com/captaincaius)
+ * feat(model): add Model.cleanIndexes() to drop non-schema indexes #6676
+ * feat(document): make `updateOne()` document middleware pass `this` to post hooks #8262
+ * feat(aggregate): run pre/post aggregate hooks on `explain()` #5887
+ * docs(model+query): add `session` option to docs for findOneAndX() methods #8396
+
 5.7.14 / 2019-12-06
 ===================
  * fix(cursor): wait until all `eachAsync()` functions finish before resolving the promise #8352
diff --git a/package.json b/package.json
index b38eaef0906..b01a67f341e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.7.15-pre",
+  "version": "5.8.0",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From c5c725aec65395af04d3bbe085603ac11f52cc97 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Dec 2019 10:25:31 -0500
Subject: [PATCH 0258/2348] chore: now working on 5.8.1

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index b01a67f341e..eefe0adbe07 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.0",
+  "version": "5.8.1-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 3a6fc709e6695f169e458adf925def128f74f72e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Dec 2019 10:25:43 -0500
Subject: [PATCH 0259/2348] test(documentarray): repro #8399

---
 test/types.documentarray.test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 8140ee484b0..7f601d5cac8 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -588,6 +588,26 @@ describe('types.documentarray', function() {
       assert.equal(friendsNames.length, 2);
       assert.equal(friendsNames[1], 'Sam');
     });
+
+    it('slice() after map() works (gh-8399)', function() {
+      const MyModel = db.model('gh8399', Schema({
+        myArray: [{ name: String }]
+      }));
+
+      const doc = new MyModel({
+        myArray: [{ name: 'a' }, { name: 'b' }]
+      });
+      let myArray = doc.myArray;
+
+      myArray = myArray.map(val => ({ name: `${val.name} mapped` }));
+
+      myArray.splice(1, 1, { name: 'c' });
+
+      assert.deepEqual(myArray.map(v => v.name), [
+        'a mapped',
+        'c',
+      ]);
+    });
   });
 
   it('cleans modified subpaths on splice() (gh-7249)', function() {

From d37758a88d0947e9f9d92768279248f6c11336f1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Dec 2019 10:26:29 -0500
Subject: [PATCH 0260/2348] fix(documentarray): set schema on the array that
 `map()` returns to support casting

Fix #8399
---
 lib/types/documentarray.js       | 13 +++++++++++++
 test/types.documentarray.test.js |  2 ++
 2 files changed, 15 insertions(+)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index bb1ce19ce71..2aac5e873ae 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -34,6 +34,19 @@ class CoreDocumentArray extends CoreMongooseArray {
     return this.toObject(internalToObjectOptions);
   }
 
+  /*!
+   * ignore
+   */
+
+  map() {
+    const ret = super.map.apply(this, arguments);
+    ret[arraySchemaSymbol] = this[arraySchemaSymbol];
+    ret[arrayPathSymbol] = null;
+    ret[arrayParentSymbol] = null;
+
+    return ret;
+  }
+
   /**
    * Overrides MongooseArray#cast
    *
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 7f601d5cac8..31201d00b29 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -602,10 +602,12 @@ describe('types.documentarray', function() {
       myArray = myArray.map(val => ({ name: `${val.name} mapped` }));
 
       myArray.splice(1, 1, { name: 'c' });
+      myArray.splice(2, 0, { name: 'd' });
 
       assert.deepEqual(myArray.map(v => v.name), [
         'a mapped',
         'c',
+        'd'
       ]);
     });
   });

From 14e1c341c31c4c0210f943701f9d227b9b72067c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Dec 2019 10:43:52 -0500
Subject: [PATCH 0261/2348] fix(documentarray): dont attempt to cast when
 modifying array returned from map() re: #8399

---
 lib/types/documentarray.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 2aac5e873ae..c85d98fbfa1 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -40,7 +40,7 @@ class CoreDocumentArray extends CoreMongooseArray {
 
   map() {
     const ret = super.map.apply(this, arguments);
-    ret[arraySchemaSymbol] = this[arraySchemaSymbol];
+    ret[arraySchemaSymbol] = null;
     ret[arrayPathSymbol] = null;
     ret[arrayParentSymbol] = null;
 
@@ -56,6 +56,9 @@ class CoreDocumentArray extends CoreMongooseArray {
    */
 
   _cast(value, index) {
+    if (this[arraySchemaSymbol] == null) {
+      return value;
+    }
     let Constructor = this[arraySchemaSymbol].casterConstructor;
     const isInstance = Constructor.$isMongooseDocumentArray ?
       value && value.isMongooseDocumentArray :

From 2c2f98bacfcd11b804623dc12d5e91d37be077e9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Dec 2019 17:45:33 -0700
Subject: [PATCH 0262/2348] fix(schema): add `$embeddedSchemaType` property to
 arrays for consistency with document arrays

Fix #8389
---
 lib/schema/array.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 4e699ec3d81..5b34182c416 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -78,6 +78,8 @@ function SchemaArray(key, cast, options, schemaOptions) {
       this.caster = caster;
     }
 
+    this.$embeddedSchemaType = this.caster;
+
     if (!(this.caster instanceof EmbeddedDoc)) {
       this.caster.path = key;
     }

From bbabfee2ddc48eea3b6da10f594bb46e1ada82d0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Dec 2019 18:39:25 -0700
Subject: [PATCH 0263/2348] fix(document): update single nested subdoc parent
 when setting to existing single nested doc

Fix #8400
---
 lib/schema/SingleNestedPath.js |  2 +-
 test/document.test.js          | 21 ++++++++++++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 46bb68eca22..b5baac63c38 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -157,7 +157,7 @@ SingleNestedPath.prototype.$conditionalHandlers.$exists = $exists;
  */
 
 SingleNestedPath.prototype.cast = function(val, doc, init, priorVal) {
-  if (val && val.$isSingleNested) {
+  if (val && val.$isSingleNested && val.parent === doc) {
     return val;
   }
 
diff --git a/test/document.test.js b/test/document.test.js
index 3d041cf065f..7fd3c0a00ab 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2571,7 +2571,7 @@ describe('document', function() {
       velvetRevolver.guitarist = gnr.guitarist;
       velvetRevolver.save(function(error) {
         assert.ifError(error);
-        assert.equal(velvetRevolver.guitarist, gnr.guitarist);
+        assert.equal(velvetRevolver.guitarist.name, 'Slash');
         done();
       });
     });
@@ -8282,4 +8282,23 @@ describe('document', function() {
       }, /Cannot call.*multiple times/);
     });
   });
+
+  it('setting a path to a single nested document should update the single nested doc parent (gh-8400)', function() {
+    const schema = Schema({
+      name: String,
+      subdoc: new Schema({
+        name: String
+      })
+    });
+    const Model = db.model('gh8400', schema);
+
+    const doc1 = new Model({ name: 'doc1', subdoc: { name: 'subdoc1' } });
+    const doc2 = new Model({ name: 'doc2', subdoc: { name: 'subdoc2' } });
+
+    doc1.subdoc = doc2.subdoc;
+    assert.equal(doc1.subdoc.name, 'subdoc2');
+    assert.equal(doc2.subdoc.name, 'subdoc2');
+    assert.strictEqual(doc1.subdoc.ownerDocument(), doc1);
+    assert.strictEqual(doc2.subdoc.ownerDocument(), doc2);
+  });
 });

From 084605e8e37f882924482edb58bb73607da78925 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Dec 2019 16:44:55 -0700
Subject: [PATCH 0264/2348] chore: add edubirdie as a sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 57354c3f748..85e641a77e3 100644
--- a/index.pug
+++ b/index.pug
@@ -268,6 +268,9 @@ html(lang='en')
               <a href="https://vpnblackfriday.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
               </a>
+              <a href="https://uk.edubirdie.com/">
+                <img class="sponsor" src="https://images.opencollective.com/uk-edubirdie-com/b1d51ab/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 83b44aedebf00c97cc6c8e8139122efb0f7bdcb6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Dec 2019 16:48:22 -0700
Subject: [PATCH 0265/2348] chore: release 5.8.1

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c1340c0d132..33819dcee42 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.8.1 / 2019-12-12
+==================
+ * fix(documentarray): dont attempt to cast when modifying array returned from map() #8399
+ * fix(document): update single nested subdoc parent when setting to existing single nested doc #8400
+ * fix(schema): add `$embeddedSchemaType` property to arrays for consistency with document arrays #8389
+
 5.8.0 / 2019-12-09
 ==================
  * feat: wrap server selection timeout errors in `MongooseTimeoutError` to retain original stack trace #8259
diff --git a/package.json b/package.json
index eefe0adbe07..6fc27cb5d93 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.1-pre",
+  "version": "5.8.1",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From d62c5e40678fb908726ab4543ac8af35f47a7341 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Dec 2019 17:49:11 +0200
Subject: [PATCH 0266/2348] Add test for #8371 (setting isNew to true inserts)

---
 test/document.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 7fd3c0a00ab..85be8fb6e0e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -1939,6 +1939,27 @@ describe('document', function() {
     });
   });
 
+  describe('gh-8371', function() {
+    it('seting isNew to true makes save tries to insert a new document (gh-8371)', function() {
+      return co(function*() {
+        const personSchema = new Schema({ name: String });
+
+        const Person = db.model('gh8371-A', personSchema);
+
+        const createdPerson = yield Person.create({name:'Hafez'});
+
+        const removedPerson = yield Person.findOneAndRemove({_id:createdPerson._id});
+
+        removedPerson.isNew = true;
+
+        yield removedPerson.save();
+
+        const foundPerson = yield Person.findOne({_id:removedPerson._id});
+        assert.ok(foundPerson);
+      });
+    });
+  });
+
   it('properly calls queue functions (gh-2856)', function(done) {
     const personSchema = new mongoose.Schema({
       name: String

From 8b2cda892616d292982d2cf8e84e79d403b23017 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Dec 2019 18:40:57 +0200
Subject: [PATCH 0267/2348] Fixes #8371

---
 lib/model.js          | 10 ++++++--
 test/document.test.js | 53 ++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 58 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index f7f1f406b84..f21d20eef92 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -309,8 +309,14 @@ Model.prototype.$__handleSave = function(options, callback) {
         callback(null, ret);
       });
     } else {
-      this.$__reset();
-      callback();
+      this.constructor.exists(this)
+        .then((documentExists)=>{
+          if (!documentExists) throw new DocumentNotFoundError(this.$__where(),this.constructor.modelName);
+
+          this.$__reset();
+          callback();
+        })
+        .catch(callback);
       return;
     }
 
diff --git a/test/document.test.js b/test/document.test.js
index 85be8fb6e0e..5efe8b5c996 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -25,6 +25,7 @@ const SchemaType = mongoose.SchemaType;
 const ValidatorError = SchemaType.ValidatorError;
 const ValidationError = mongoose.Document.ValidationError;
 const MongooseError = mongoose.Error;
+const DocumentNotFoundError = mongoose.Error.DocumentNotFoundError;
 
 /**
  * Test Document constructor.
@@ -1940,14 +1941,12 @@ describe('document', function() {
   });
 
   describe('gh-8371', function() {
-    it('seting isNew to true makes save tries to insert a new document (gh-8371)', function() {
+    it('setting isNew to true makes save tries to insert a new document (gh-8371)', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
-
         const Person = db.model('gh8371-A', personSchema);
 
         const createdPerson = yield Person.create({name:'Hafez'});
-
         const removedPerson = yield Person.findOneAndRemove({_id:createdPerson._id});
 
         removedPerson.isNew = true;
@@ -1958,6 +1957,54 @@ describe('document', function() {
         assert.ok(foundPerson);
       });
     });
+
+    it('saving a document with no changes, throws an error when document is not found', function() {
+      return co(function*() {
+        const personSchema = new Schema({ name: String });
+        const Person = db.model('gh8371-B', personSchema);
+
+        const person = yield Person.create({name:'Hafez'});
+
+        yield Person.deleteOne({_id:person._id});
+
+        let threw = false;
+        try {
+          yield person.save();
+        }
+        catch (err) {
+          assert.equal(err instanceof DocumentNotFoundError, true);
+          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-B"`);
+          threw = true;
+        }
+
+        assert.equal(threw,true);
+      });
+    });
+
+    it('saving a document with changes, throws an error when document is not found', function() {
+      return co(function*() {
+        const personSchema = new Schema({ name: String });
+        const Person = db.model('gh8371-C', personSchema);
+
+        const person = yield Person.create({name:'Hafez'});
+
+        yield Person.deleteOne({_id:person._id});
+
+        person.name = 'Different Name';
+
+        let threw = false;
+        try {
+          yield person.save();
+        }
+        catch (err) {
+          assert.equal(err instanceof DocumentNotFoundError,true);
+          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-C"`);
+          threw = true;
+        }
+
+        assert.equal(threw,true);
+      });
+    });
   });
 
   it('properly calls queue functions (gh-2856)', function(done) {

From 31a3cc7d01d8fa207003d549bfe08a15e304252c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Dec 2019 18:42:16 +0200
Subject: [PATCH 0268/2348] Use _id for exists instead of sending whole
 document

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index f21d20eef92..7e4f2395509 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -309,7 +309,7 @@ Model.prototype.$__handleSave = function(options, callback) {
         callback(null, ret);
       });
     } else {
-      this.constructor.exists(this)
+      this.constructor.exists({_id:this._id})
         .then((documentExists)=>{
           if (!documentExists) throw new DocumentNotFoundError(this.$__where(),this.constructor.modelName);
 

From 9fbd2b72e2874de509f89d2b0b8d9ac90b772fbf Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 15 Dec 2019 16:50:58 +0200
Subject: [PATCH 0269/2348] Fix failing test

---
 test/model.discriminator.querying.test.js | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 83c55da1a8c..61db4e8344a 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -177,16 +177,10 @@ describe('model', function() {
       });
 
       describe('discriminator model only finds documents of its type', function() {
-        let impressionEvent, conversionEvent1, conversionEvent2;
-
-        before(function() {
-          impressionEvent = new ImpressionEvent({name: 'Impression event'});
-          conversionEvent1 = new ConversionEvent({name: 'Conversion event 1', revenue: 1});
-          conversionEvent2 = new ConversionEvent({name: 'Conversion event 2', revenue: 2});
-        });
 
         describe('using "ModelDiscriminator#findById"', function() {
           it('to find a document of the appropriate discriminator', function(done) {
+            const impressionEvent = new ImpressionEvent({name: 'Impression event'});
             impressionEvent.save(function(err) {
               assert.ifError(err);
 
@@ -217,6 +211,9 @@ describe('model', function() {
 
         describe('using "ModelDiscriminator#find"', function() {
           it('to find documents of the appropriate discriminator', function(done) {
+            const impressionEvent = new ImpressionEvent({name: 'Impression event'});
+            const conversionEvent1 = new ConversionEvent({name: 'Conversion event 1', revenue: 1});
+            const conversionEvent2 = new ConversionEvent({name: 'Conversion event 2', revenue: 2});
             impressionEvent.save(function(err) {
               assert.ifError(err);
               conversionEvent1.save(function(err) {

From 9d1da7e16dbc1e2a91532adeed54edb96f87e232 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 15 Dec 2019 16:56:15 +0200
Subject: [PATCH 0270/2348] Use the more general this.$__where() instead of
 this._id

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 7e4f2395509..171f95f57c4 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -309,7 +309,7 @@ Model.prototype.$__handleSave = function(options, callback) {
         callback(null, ret);
       });
     } else {
-      this.constructor.exists({_id:this._id})
+      this.constructor.exists(this.$__where())
         .then((documentExists)=>{
           if (!documentExists) throw new DocumentNotFoundError(this.$__where(),this.constructor.modelName);
 

From cb5af1f4cd21b6c567dc53431a1218a330354870 Mon Sep 17 00:00:00 2001
From: jaschaio <me@jascha.io>
Date: Mon, 16 Dec 2019 13:38:36 +0100
Subject: [PATCH 0271/2348] Update mongodb dependency to 3.4

Connecting via `ssl: true` in a Docker Container through a SSH Tunnel fails for me.

Using `mongodb@3.4` and the new `tls: true` parameters works as expected.

Would be great if mongoose could be updated to use the latest `mongodb@3.4` instead of `3.3.4`
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 6fc27cb5d93..4204ca4b745 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.3.5",
+    "mongodb": "3.4.0",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From 82fc0044fa4c43d17fe6c068c6e0b7433c9734e3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Dec 2019 08:38:03 -0700
Subject: [PATCH 0272/2348] test: repro #8392

---
 test/model.findOneAndUpdate.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index e1f4ef0b3c6..f9bb43bb461 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -2436,4 +2436,21 @@ describe('model: findOneAndUpdate:', function() {
       assert.equal(doc.shape.radius, 10);
     });
   });
+
+  it('setDefaultsOnInsert with doubly nested subdocs (gh-8392)', function() {
+    const nestedSchema = Schema({ name: String });
+    const Model = db.model('gh8392', Schema({
+      L1: Schema({
+        L2: {
+          type: nestedSchema,
+          default: () => ({ name: 'foo' })
+        }
+      }),
+      prop: String
+    }));
+
+    const opts = { upsert: true, setDefaultsOnInsert: true, new: true };
+    return Model.findOneAndUpdate({}, { prop: 'foo', L1: {} }, opts).lean().
+      then(doc => assert.equal(doc.L1.L2.name, 'foo'));
+  });
 });

From 368871a1d95d2b77ae7751f3a51f102d43e6aec2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Dec 2019 08:38:24 -0700
Subject: [PATCH 0273/2348] fix: handle setDefaultsOnInsert with deeply nested
 subdocs

Fix #8392
---
 lib/types/subdocument.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index ce23a5afb79..b360b6982d1 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -125,7 +125,7 @@ Subdocument.prototype.isModified = function(paths, modifiedPaths) {
     return this.$parent.isModified(paths, modifiedPaths);
   }
 
-  return Document.prototype.isModified(paths, modifiedPaths);
+  return Document.prototype.isModified.call(this, paths, modifiedPaths);
 };
 
 /**

From f494adcdd50b8b28185410dca0f8dceee01d333e Mon Sep 17 00:00:00 2001
From: Captain Caius <241342+captaincaius@users.noreply.github.com>
Date: Tue, 17 Dec 2019 12:29:17 -0800
Subject: [PATCH 0274/2348] allow browser build to be published (fix #8427)

---
 .npmignore | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.npmignore b/.npmignore
index 9e48062c669..4d835952c43 100644
--- a/.npmignore
+++ b/.npmignore
@@ -15,7 +15,6 @@ bin/
 tools/31*
 *.key
 data/
-dist/
 
 *.txt
 *.png
@@ -33,4 +32,4 @@ website.js
 .config*
 
 migrating_to_5.md
-renovate.json
\ No newline at end of file
+renovate.json

From 5ccce74dbc854d59c7e653c32c43b72da180e3f9 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 18 Dec 2019 14:51:58 +0200
Subject: [PATCH 0275/2348] Add test case for setting isNew to true on existing
 doc

---
 test/document.test.js | 30 ++++++++++++++++++++++++++----
 1 file changed, 26 insertions(+), 4 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 5efe8b5c996..27c9e8531fb 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -1958,11 +1958,33 @@ describe('document', function() {
       });
     });
 
-    it('saving a document with no changes, throws an error when document is not found', function() {
+    it('setting isNew to true throws an error when a document already exists (gh-8371)', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('gh8371-B', personSchema);
 
+        const createdPerson = yield Person.create({name:'Hafez'});
+
+        createdPerson.isNew = true;
+
+        let threw = false;
+        try {
+          yield createdPerson.save();
+        }
+        catch (err) {
+          threw = true;
+          assert.equal(err.code, 11000);
+        }
+
+        assert.equal(threw,true);
+      });
+    });
+
+    it('saving a document with no changes, throws an error when document is not found', function() {
+      return co(function*() {
+        const personSchema = new Schema({ name: String });
+        const Person = db.model('gh8371-C', personSchema);
+
         const person = yield Person.create({name:'Hafez'});
 
         yield Person.deleteOne({_id:person._id});
@@ -1973,7 +1995,7 @@ describe('document', function() {
         }
         catch (err) {
           assert.equal(err instanceof DocumentNotFoundError, true);
-          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-B"`);
+          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-C"`);
           threw = true;
         }
 
@@ -1984,7 +2006,7 @@ describe('document', function() {
     it('saving a document with changes, throws an error when document is not found', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
-        const Person = db.model('gh8371-C', personSchema);
+        const Person = db.model('gh8371-D', personSchema);
 
         const person = yield Person.create({name:'Hafez'});
 
@@ -1998,7 +2020,7 @@ describe('document', function() {
         }
         catch (err) {
           assert.equal(err instanceof DocumentNotFoundError,true);
-          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-C"`);
+          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-D"`);
           threw = true;
         }
 

From 6c39e234a3a04d26ba1191e602765befec95d498 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 19 Dec 2019 20:16:28 -0600
Subject: [PATCH 0276/2348] test(document): repro #8443

---
 test/document.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 7fd3c0a00ab..9996427ef77 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8301,4 +8301,29 @@ describe('document', function() {
     assert.strictEqual(doc1.subdoc.ownerDocument(), doc1);
     assert.strictEqual(doc2.subdoc.ownerDocument(), doc2);
   });
+
+  it('setting an array to an array with some populated documents depopulates the whole array (gh-8443)', function() {
+    const A = db.model('gh8443_A', Schema({
+      name: String,
+      rel: [{ type: mongoose.ObjectId, ref: 'gh8443_B' }]
+    }));
+
+    const B = db.model('gh8443_B', Schema({ name: String }));
+
+    return co(function*() {
+      const b = yield B.create({ name: 'testb' });
+      yield A.create({ name: 'testa', rel: [b._id] });
+
+      const a = yield A.findOne().populate('rel');
+      console.log(a.populated('rel'), a.rel);
+
+      const b2 = yield B.create({ name: 'testb2' });
+      a.rel = [a.rel[0], b2._id];
+      yield a.save();
+
+      assert.ok(!a.populated('rel'));
+      assert.ok(a.rel[0] instanceof mongoose.Types.ObjectId);
+      assert.ok(a.rel[1] instanceof mongoose.Types.ObjectId);
+    });
+  });
 });

From 3d2e411f52e96fdd0b1dcea066cd20b6b609f4f1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 19 Dec 2019 20:17:10 -0600
Subject: [PATCH 0277/2348] fix(document): depopulate entire array when setting
 array path to a partially populated array

Fix #8443
---
 lib/document.js       | 43 ++++++++++++++++++++++++++++++++++++++-----
 test/document.test.js |  1 -
 2 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4daa85b280d..3e09e6f0453 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1143,11 +1143,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
         Array.isArray(schema.options[this.schema.options.typeKey]) &&
         schema.options[this.schema.options.typeKey].length &&
         schema.options[this.schema.options.typeKey][0].ref &&
-        Array.isArray(val) &&
-        val.length > 0 &&
-        val[0] instanceof Document &&
-        val[0].constructor.modelName &&
-        (schema.options[this.schema.options.typeKey][0].ref === val[0].constructor.baseModelName || schema.options[this.schema.options.typeKey][0].ref === val[0].constructor.modelName)) {
+        _isManuallyPopulatedArray(val, schema.options[this.schema.options.typeKey][0].ref)) {
       if (this.ownerDocument) {
         popOpts = { [populateModelSymbol]: val[0].constructor };
         this.ownerDocument().populated(this.$__fullPath(path),
@@ -1183,6 +1179,15 @@ Document.prototype.$set = function $set(path, val, type, options) {
     }
 
     if (!didPopulate && this.$__.populated) {
+      // If this array partially contains populated documents, convert them
+      // all to ObjectIds re: #8443
+      if (Array.isArray(val) && this.$__.populated[path]) {
+        for (let i = 0; i < val.length; ++i) {
+          if (val[i] instanceof Document) {
+            val[i] = val[i]._id;
+          }
+        }
+      }
       delete this.$__.populated[path];
     }
 
@@ -1208,6 +1213,34 @@ Document.prototype.$set = function $set(path, val, type, options) {
   return this;
 };
 
+/*!
+ * ignore
+ */
+
+function _isManuallyPopulatedArray(val, ref) {
+  if (!Array.isArray(val)) {
+    return false;
+  }
+  if (val.length === 0) {
+    return false;
+  }
+
+  for (const el of val) {
+    if (!(el instanceof Document)) {
+      return false;
+    }
+    const modelName = el.constructor.modelName;
+    if (modelName == null) {
+      return false;
+    }
+    if (el.constructor.modelName != ref && el.constructor.baseModelName != ref) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
 /**
  * Sets the value of a path, or many paths.
  *
diff --git a/test/document.test.js b/test/document.test.js
index 9996427ef77..e3ee5e00ab4 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8315,7 +8315,6 @@ describe('document', function() {
       yield A.create({ name: 'testa', rel: [b._id] });
 
       const a = yield A.findOne().populate('rel');
-      console.log(a.populated('rel'), a.rel);
 
       const b2 = yield B.create({ name: 'testb2' });
       a.rel = [a.rel[0], b2._id];

From 532d798df460ec1f4d79b8ddfdb8792b673f738f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 12:06:18 -0500
Subject: [PATCH 0278/2348] docs(populate): clarify limitations of `limit`
 option for populate and suggest workaround

Fix #8409
---
 docs/populate.pug | 50 ++++++++++++++++++++++++++++++++++++++++++-----
 lib/model.js      |  1 +
 lib/query.js      |  1 +
 3 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 16c26d43b2a..7fa462d8614 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -218,22 +218,62 @@ block content
 
     <h3 id="query-conditions"><a href="#query-conditions">Query conditions and other options</a></h3>
 
-    What if we wanted to populate our fans array based on their age, select
-    just their names, and return at most, any 5 of them?
+    What if we wanted to populate our fans array based on their age and
+    select just their names?
 
     ```javascript
     Story.
       find(...).
       populate({
         path: 'fans',
-        match: { age: { $gte: 21 }},
+        match: { age: { $gte: 21 } },
         // Explicitly exclude `_id`, see http://bit.ly/2aEfTdB
-        select: 'name -_id',
-        options: { limit: 5 }
+        select: 'name -_id'
       }).
       exec();
     ```
 
+    Populate does support a `limit` option, however, it currently
+    does **not** limit on a per-document basis. For example, suppose
+    you have 2 stories:
+
+    ```javascript
+    Story.create([
+      { title: 'Casino Royale', fans: [1, 2, 3, 4, 5, 6, 7, 8] },
+      { title: 'Live and Let Die', fans: [9, 10] }
+    ]);
+    ```
+
+    If you were to `populate()` using the `limit` option, you
+    would find that the 2nd story has 0 fans:
+
+    ```javascript
+    const stories = Story.find().sort({ name: 1 }).populate({
+      path: 'fans',
+      options: { limit: 2 }
+    });
+
+    stories[0].fans.length; // 2
+    stories[1].fans.length; // 0
+    ```
+
+    That's because, in order to avoid executing a separate query
+    for each document, Mongoose instead queries for fans using
+    `numDocuments * limit` as the limit. As a workaround, you
+    should populate each document individually:
+
+    ```javascript
+    const stories = await Story.find().sort({ name: 1 });
+    for (const story of stories) {
+      await story.
+        populate({ path: 'fans', options: { limit: 2 } }).
+        execPopulate();
+    }
+
+    stories[0].fans.length; // 2
+    stories[1].fans.length; // 2
+    ```
+
     <h3 id="refs-to-children"><a href="#refs-to-children">Refs to children</a></h3>
 
     We may find however, if we use the `author` object, we are unable to get a
diff --git a/lib/model.js b/lib/model.js
index f7f1f406b84..7e983427e3c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4172,6 +4172,7 @@ Model.geoSearch = function(conditions, options, callback) {
  * @param {boolean} [options.clone=false] When you do `BlogPost.find().populate('author')`, blog posts with the same author will share 1 copy of an `author` doc. Enable this option to make Mongoose clone populated docs before assigning them.
  * @param {Object|Function} [options.match=null] Add an additional filter to the populate query. Can be a filter object containing [MongoDB query syntax](https://docs.mongodb.com/manual/tutorial/query-documents/), or a function that returns a filter object.
  * @param {Boolean} [options.skipInvalidIds=false] By default, Mongoose throws a cast error if `localField` and `foreignField` schemas don't line up. If you enable this option, Mongoose will instead filter out any `localField` properties that cannot be casted to `foreignField`'s schema type.
+ * @param {Object} [options.options=null] Additional options like `limit` and `lean`.
  * @param {Function} [callback(err,doc)] Optional callback, executed upon completion. Receives `err` and the `doc(s)`.
  * @return {Promise}
  * @api public
diff --git a/lib/query.js b/lib/query.js
index 0560f637dad..c749a6bebd3 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4564,6 +4564,7 @@ function castDoc(query, overwrite) {
  * @param {boolean} [options.getters=false] if true, Mongoose will call any getters defined on the `localField`. By default, Mongoose gets the raw value of `localField`. For example, you would need to set this option to `true` if you wanted to [add a `lowercase` getter to your `localField`](/docs/schematypes.html#schematype-options).
  * @param {boolean} [options.clone=false] When you do `BlogPost.find().populate('author')`, blog posts with the same author will share 1 copy of an `author` doc. Enable this option to make Mongoose clone populated docs before assigning them.
  * @param {Object|Function} [options.match=null] Add an additional filter to the populate query. Can be a filter object containing [MongoDB query syntax](https://docs.mongodb.com/manual/tutorial/query-documents/), or a function that returns a filter object.
+ * @param {Object} [options.options=null] Additional options like `limit` and `lean`.
  * @see population ./populate.html
  * @see Query#select #query_Query-select
  * @see Model.populate #model_Model.populate

From 32d75dbf4c77f3bfacd4d6235fbb6694289d2250 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 12:59:43 -0500
Subject: [PATCH 0279/2348] docs(deprecations): explain which connection
 options are no longer relevant with useUnifiedTopology

Fix #8411
---
 docs/connections.pug  | 15 ++++++++++-----
 docs/deprecations.pug | 12 ++++++++++++
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 4246f7e967e..b4fd6ab53d5 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -136,21 +136,26 @@ block content
     * `autoIndex`         - By default, mongoose will automatically build indexes defined in your schema when it connects. This is great for development, but not ideal for large production deployments, because index builds can cause performance degradation. If you set `autoIndex` to false, mongoose will not automatically build indexes for **any** model associated with this connection.
     * `dbName`            - Specifies which database to connect to and overrides any database specified in the connection string. This is useful if you are unable to specify a default database in the connection string like with [some `mongodb+srv` syntax connections](https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626).
 
-    Below are some of the options that are important for tuning mongoose.
+    Below are some of the options that are important for tuning Mongoose.
 
     * `useNewUrlParser`   - The underlying MongoDB driver has deprecated their current [connection string](https://docs.mongodb.com/manual/reference/connection-string/) parser. Because this is a major change, they added the `useNewUrlParser` flag to allow users to fall back to the old parser if they find a bug in the new parser. You should set `useNewUrlParser: true` unless that prevents you from connecting. Note that if you specify `useNewUrlParser: true`, you **must** specify a port in your connection string, like `mongodb://localhost:27017/dbname`. The new url parser does _not_ support connection strings that do not have a port, like `mongodb://localhost/dbname`.
     * `useCreateIndex`    - False by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
     * `useFindAndModify`  - True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
-    * `autoReconnect`     - The underlying MongoDB driver will automatically try to reconnect when it loses connection to MongoDB. Unless you are an extremely advanced user that wants to manage their own connection pool, do **not** set this option to `false`.
-    * `reconnectTries`    - If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
-    * `reconnectInterval` - See `reconnectTries`
+    * `useUnifiedTopology`- False by default. Set to `true` to opt in to using [the MongoDB driver's new connection management engine](/docs/deprecations.html#useunifiedtopology). You should set this option to `true`, except for the unlikely case that it prevents you from maintaining a stable connection.
     * `promiseLibrary`    - Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
     * `poolSize`          - The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
-    * `bufferMaxEntries`  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
     * `connectTimeoutMS`  - How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
     * `socketTimeoutMS`   - How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
     * `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
 
+    The following options are important for tuning Mongoose only if you are
+    running **without** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
+
+    * `autoReconnect`     - The underlying MongoDB driver will automatically try to reconnect when it loses connection to MongoDB. Unless you are an extremely advanced user that wants to manage their own connection pool, do **not** set this option to `false`.
+    * `reconnectTries`    - If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
+    * `reconnectInterval` - See `reconnectTries`
+    * `bufferMaxEntries`  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
+
     Example:
 
     ```javascript
diff --git a/docs/deprecations.pug b/docs/deprecations.pug
index 1f642432022..d847147db90 100644
--- a/docs/deprecations.pug
+++ b/docs/deprecations.pug
@@ -192,6 +192,18 @@ block content
     mongoose.set('useUnifiedTopology', true);
     ```
 
+    The `useUnifiedTopology` option removes support for several
+    [connection options](/docs/connections.html#options) that are
+    no longer relevant with the new topology engine:
+
+    - `autoReconnect`
+    - `reconnectTries`
+    - `reconnectInterval`
+
+    When you enable `useUnifiedTopology`, please remove those options
+    from your [`mongoose.connect()`](/docs/api/mongoose.html#mongoose_Mongoose-connect) or
+    [`createConnection()`](/docs/api/mongoose.html#mongoose_Mongoose-createConnection) calls.
+
     If you find any unexpected behavior, please [open up an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
 
     ## `update()`

From 5944ebf37baa297422cae12ddbece35756ed0e54 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 13:53:21 -0500
Subject: [PATCH 0280/2348] chore: now working on 5.8.2

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 6fc27cb5d93..e8a0dad7a59 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.1",
+  "version": "5.8.2-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9e407b3f04115cba3933de456f894fdc0d6dc73d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 13:53:41 -0500
Subject: [PATCH 0281/2348] test(cursor): repro #8421

---
 test/query.cursor.test.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index f29b4b6deeb..2905e8a45d5 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -475,4 +475,12 @@ describe('QueryCursor', function() {
         assert.equal(cursor.cursor.cursorState.batchSize, 2001);
       });
   });
+
+  it('pulls schema-level readPreference (gh-8421)', function() {
+    const read = 'secondaryPreferred';
+    const User = db.model('gh8421', Schema({ name: String }, { read }));
+    const cursor = User.find().cursor();
+
+    assert.equal(cursor.options.readPreference.mode, read);
+  });
 });

From 263fe029800435d6b89684bee30931eb9cf5da04 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 13:54:06 -0500
Subject: [PATCH 0282/2348] fix(cursor): pull schema-level readPreference when
 using `Query#cursor()`

Fix #8421
---
 lib/cursor/QueryCursor.js | 22 ++++++++++++++++------
 lib/query.js              |  2 +-
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 82b43043af4..4d74dcedf85 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -42,19 +42,20 @@ function QueryCursor(query, options) {
   this._mongooseOptions = {};
   this._transforms = [];
   this.model = model;
+  this.options = options || {};
+
   model.hooks.execPre('find', query, () => {
     this._transforms = this._transforms.concat(query._transforms.slice());
-    if (options.transform) {
+    if (this.options.transform) {
       this._transforms.push(options.transform);
     }
     // Re: gh-8039, you need to set the `cursor.batchSize` option, top-level
     // `batchSize` option doesn't work.
-    options = options || {};
-    if (options.batchSize) {
-      options.cursor = options.cursor || {};
-      options.cursor.batchSize = options.batchSize;
+    if (this.options.batchSize) {
+      this.options.cursor = options.cursor || {};
+      this.options.cursor.batchSize = options.batchSize;
     }
-    model.collection.find(query._conditions, options, function(err, cursor) {
+    model.collection.find(query._conditions, this.options, function(err, cursor) {
       if (_this._error) {
         cursor.close(function() {});
         _this.listeners('error').length > 0 && _this.emit('error', _this._error);
@@ -214,6 +215,15 @@ QueryCursor.prototype.eachAsync = function(fn, opts, callback) {
   return eachAsync(function(cb) { return _next(_this, cb); }, fn, opts, callback);
 };
 
+/**
+ * The `options` passed in to the `QueryCursor` constructor.
+ *
+ * @api public
+ * @property options
+ */
+
+QueryCursor.prototype.options;
+
 /**
  * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
  * Useful for setting the `noCursorTimeout` and `tailable` flags.
diff --git a/lib/query.js b/lib/query.js
index c749a6bebd3..40447f60522 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4839,7 +4839,7 @@ Query.prototype.cursor = function cursor(opts) {
     this.setOptions(opts);
   }
 
-  const options = Object.assign({}, this.options, {
+  const options = Object.assign({}, this._optionsForExec(), {
     projection: this.projection()
   });
   try {

From ce6d4ba46ac4259d7bd753294ceaee4de2dd599e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 14:54:02 -0500
Subject: [PATCH 0283/2348] test(cursor): repro #8422

---
 test/query.cursor.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 2905e8a45d5..fbafb97ec5c 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -483,4 +483,27 @@ describe('QueryCursor', function() {
 
     assert.equal(cursor.options.readPreference.mode, read);
   });
+
+  it('eachAsync() with parallel > numDocs (gh-8422)', function() {
+    const schema = new mongoose.Schema({ name: String });
+    const Movie = db.model('gh8422', schema);
+
+    return co(function*() {
+      yield Movie.create([
+        { name: 'Kickboxer' },
+        { name: 'Ip Man' },
+        { name: 'Enter the Dragon' }
+      ]);
+  
+      let numDone = 0;
+  
+      const test = co.wrap(function*() {
+        yield new Promise((resolve) => setTimeout(resolve, 100));
+        ++numDone;
+      });
+  
+      yield Movie.find().cursor().eachAsync(test, { parallel: 4 })
+      assert.equal(numDone, 3);
+    });
+  });
 });

From 3133e50b08e622df207e7cd0fc274f113b873379 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 15:25:39 -0500
Subject: [PATCH 0284/2348] fix(cursor): wait for all promises to resolve if
 `parallel` is greater than number of documents

Fix #8422
---
 lib/helpers/cursor/eachAsync.js | 5 ++++-
 test/query.cursor.test.js       | 8 ++++----
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 029f203c9eb..7483cc0694e 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -66,9 +66,12 @@ module.exports = function eachAsync(next, fn, options, callback) {
           return done();
         }
 
+        ++handleResultsInProgress;
+
+        // Kick off the subsequent `next()` before handling the result, but
+        // make sure we know that we still have a result to handle re: #8422
         done();
 
-        ++handleResultsInProgress;
         handleNextResult(doc, function(err) {
           --handleResultsInProgress;
           if (err != null) {
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index fbafb97ec5c..83b0a48984a 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -494,15 +494,15 @@ describe('QueryCursor', function() {
         { name: 'Ip Man' },
         { name: 'Enter the Dragon' }
       ]);
-  
+
       let numDone = 0;
-  
+
       const test = co.wrap(function*() {
         yield new Promise((resolve) => setTimeout(resolve, 100));
         ++numDone;
       });
-  
-      yield Movie.find().cursor().eachAsync(test, { parallel: 4 })
+
+      yield Movie.find().cursor().eachAsync(test, { parallel: 4 });
       assert.equal(numDone, 3);
     });
   });

From cc2664af1bcfc1d24d6d28a49921366f277bf21d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 16:33:19 -0500
Subject: [PATCH 0285/2348] test(schema): repro #8429

---
 test/schema.test.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index e4a7fea14ee..08e3010ab03 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2339,4 +2339,14 @@ describe('schema', function() {
       assert.ok(threw);
     });
   });
+
+  it('copies `.add()`-ed paths when calling `.add()` with a schema argument (gh-8429)', function() {
+    const ToySchema = Schema();
+    ToySchema.add({ name: String, color: String, price: Number });
+
+    const TurboManSchema = Schema();
+    TurboManSchema.add(ToySchema).add({ year: Number });
+
+    assert.equal(TurboManSchema.path('name').instance, 'String');
+  });
 });

From 2d13d1d638e01d85d77c1e195ac60468ef1649dc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 16:33:54 -0500
Subject: [PATCH 0286/2348] fix(schema): copy `.add()`-ed paths when calling
 `.add()` with schema argument

Fix #8429
---
 lib/helpers/schema/merge.js | 2 +-
 lib/schema.js               | 8 ++++++++
 test/schema.test.js         | 3 +++
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/schema/merge.js b/lib/helpers/schema/merge.js
index c386a0bc103..d206500c440 100644
--- a/lib/helpers/schema/merge.js
+++ b/lib/helpers/schema/merge.js
@@ -1,7 +1,7 @@
 'use strict';
 
 module.exports = function merge(s1, s2) {
-  s1.add(s2.obj || {});
+  s1.add(s2.tree || {});
 
   s1.callQueue = s1.callQueue.concat(s2.callQueue);
   s1.method(s2.methods);
diff --git a/lib/schema.js b/lib/schema.js
index 09227ddd0aa..9750f8532fd 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -471,6 +471,10 @@ Schema.prototype.add = function add(obj, prefix) {
     if (key === '_id' && obj[key] === false) {
       continue;
     }
+    if (obj[key] instanceof VirtualType) {
+      this.virtual(obj[key]);
+      continue;
+    }
 
     if (Array.isArray(obj[key]) && obj[key].length === 1 && obj[key][0] == null) {
       throw new TypeError('Invalid value for schema Array path `' + fullPath +
@@ -1706,6 +1710,10 @@ Schema.prototype.indexes = function() {
  */
 
 Schema.prototype.virtual = function(name, options) {
+  if (name instanceof VirtualType) {
+    return this.virtual(name.path, name.options);
+  }
+
   if (utils.hasUserDefinedProperty(options, ['ref', 'refPath'])) {
     if (!options.localField) {
       throw new Error('Reference virtuals require `localField` option');
diff --git a/test/schema.test.js b/test/schema.test.js
index 08e3010ab03..eb4a532776e 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2348,5 +2348,8 @@ describe('schema', function() {
     TurboManSchema.add(ToySchema).add({ year: Number });
 
     assert.equal(TurboManSchema.path('name').instance, 'String');
+    assert.equal(TurboManSchema.path('color').instance, 'String');
+    assert.equal(TurboManSchema.path('price').instance, 'Number');
+    assert.equal(TurboManSchema.path('year').instance, 'Number');
   });
 });

From 6bc7e915fbc971e6c01976ab5adbe265e3b9c526 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Dec 2019 17:21:07 -0500
Subject: [PATCH 0287/2348] chore: release 5.8.2

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 33819dcee42..ae4f7ed796b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.8.2 / 2019-12-20
+==================
+ * fix(schema): copy `.add()`-ed paths when calling `.add()` with schema argument #8429
+ * fix(cursor): pull schema-level readPreference when using `Query#cursor()` #8421
+ * fix(cursor): wait for all promises to resolve if `parallel` is greater than number of documents #8422
+ * fix(document): depopulate entire array when setting array path to a partially populated array #8443
+ * fix: handle setDefaultsOnInsert with deeply nested subdocs #8392
+ * fix(document): report `DocumentNotFoundError` if underlying document deleted but no changes made #8428 #8371 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(populate): clarify limitations of `limit` option for populate and suggest workaround #8409
+ * docs(deprecations): explain which connection options are no longer relevant with useUnifiedTopology #8411
+ * chore: allow browser build to be published #8435 #8427 [captaincaius](https://github.com/captaincaius)
+
 5.8.1 / 2019-12-12
 ==================
  * fix(documentarray): dont attempt to cast when modifying array returned from map() #8399
diff --git a/package.json b/package.json
index e8a0dad7a59..aba9dc210f5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.2-pre",
+  "version": "5.8.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 58f557bccf78bcde1cf026e2bfa507236b4283c9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 11:33:18 -0500
Subject: [PATCH 0288/2348] test(populate): repro #8432

---
 test/model.populate.test.js | 60 +++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 2ca2b2855bf..285d8435860 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8872,4 +8872,64 @@ describe('model: populate:', function() {
       });
     });
   });
+
+  it('doesnt insert empty document when populating a path within a non-existent document array (gh-8432)', function() {
+    const companySchema = new mongoose.Schema({
+      name: String
+    });
+    const Company = db.model('gh8432_Companies', companySchema);
+    
+    const userSchema = new mongoose.Schema({
+      fullName: String,
+      companyId: {
+        type: mongoose.ObjectId,
+        ref: 'gh8432_Companies'
+      }
+    });
+    const User = db.model('gh8432_Users', userSchema);
+    
+    const fileSchema = new mongoose.Schema({
+      _id: String,
+      uploaderId: {
+        type: mongoose.ObjectId,
+        ref: 'gh8432_Users'
+      }
+    }, { toObject: { virtuals: true }, toJSON: { virtuals: true } });
+    fileSchema.virtual('uploadedBy', {
+      ref: 'gh8432_Users',
+      localField: 'uploaderId',
+      foreignField: '_id',
+      justOne: true
+    });
+    
+    const rideSchema = new mongoose.Schema({
+      title: String,
+      files: { type: [fileSchema], default: [] }
+    }, { toObject: { virtuals: true }, toJSON: { virtuals: true } });
+    const Ride = db.model('gh8432_Ride', rideSchema);
+
+    return co(function*() {
+      const company = yield Company.create({ name: 'Apple' });
+      const user = yield User.create({ fullName: 'John Doe', companyId: company._id });
+      yield Ride.create([
+        { title: 'London-Paris' },
+        {
+          title: 'Berlin-Moscow',
+          files: [{ _id: '123', uploaderId: user._id }]
+        }
+      ]);
+      yield Ride.updateMany({}, { $unset: { files: 1 } });  
+
+      const populatedRides = yield Ride.find({}).populate({
+        path: 'files.uploadedBy',
+        justOne: true,
+        populate: {
+          path: 'companyId',
+          justOne: true
+        }
+      });
+      assert.deepEqual(populatedRides[0].files, []);
+      assert.deepEqual(populatedRides[1].files, []);
+    });
+  });
 });

From d7b7d11040ee61fb85f5a27685153effaf79f3fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 11:34:42 -0500
Subject: [PATCH 0289/2348] fix(populate): don't add empty subdocument to array
 when populating path underneath a non-existent document array

Fix #8432
---
 lib/helpers/populate/getModelsMapForPopulate.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index d2c3e449672..cdd407dfc3b 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -172,6 +172,10 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       ret = convertTo_id(utils.getValue(localField, doc), schema);
     }
 
+    if (ret === undefined) {
+      continue;
+    }
+
     const id = String(utils.getValue(foreignField, doc));
     options._docs[id] = Array.isArray(ret) ? ret.slice() : ret;
 

From 7dcee705e0d0730553de758bb0262ea060a86400 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 11:35:48 -0500
Subject: [PATCH 0290/2348] chore: now working on 5.8.3

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index aba9dc210f5..021df6d17c4 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.2",
+  "version": "5.8.3-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From e5c6b8cfb931dc3b7e323f3d621ef1f5a56a4f1e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 11:38:41 -0500
Subject: [PATCH 0291/2348] fix: upgrade mongodb -> 3.4.1, fix tests from #8430

---
 package.json            | 2 +-
 test/connection.test.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 1c882a8793b..a9f65c294d3 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.4.0",
+    "mongodb": "3.4.1",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",
diff --git a/test/connection.test.js b/test/connection.test.js
index 170d0782380..47e4b30cb58 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -509,7 +509,7 @@ describe('connections:', function() {
   describe('connect callbacks', function() {
     it('should return an error if malformed uri passed', function(done) {
       const db = mongoose.createConnection('mongodb:///fake', { useNewUrlParser: true }, function(err) {
-        assert.ok(/hostname/.test(err.message));
+        assert.equal(err.name, 'MongoParseError');
         done();
       });
       db.close();

From 0e619d03eec75731bd09d41758a26b5d61027274 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 11:40:32 -0500
Subject: [PATCH 0292/2348] style: fix lint

---
 test/model.populate.test.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 285d8435860..1b36644aae4 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8878,7 +8878,7 @@ describe('model: populate:', function() {
       name: String
     });
     const Company = db.model('gh8432_Companies', companySchema);
-    
+
     const userSchema = new mongoose.Schema({
       fullName: String,
       companyId: {
@@ -8887,7 +8887,7 @@ describe('model: populate:', function() {
       }
     });
     const User = db.model('gh8432_Users', userSchema);
-    
+
     const fileSchema = new mongoose.Schema({
       _id: String,
       uploaderId: {
@@ -8901,7 +8901,7 @@ describe('model: populate:', function() {
       foreignField: '_id',
       justOne: true
     });
-    
+
     const rideSchema = new mongoose.Schema({
       title: String,
       files: { type: [fileSchema], default: [] }
@@ -8918,7 +8918,7 @@ describe('model: populate:', function() {
           files: [{ _id: '123', uploaderId: user._id }]
         }
       ]);
-      yield Ride.updateMany({}, { $unset: { files: 1 } });  
+      yield Ride.updateMany({}, { $unset: { files: 1 } });
 
       const populatedRides = yield Ride.find({}).populate({
         path: 'files.uploadedBy',

From 4dd84f2c16de9f0d2bbbcaef4c04775b4cae1c88 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 14:56:56 -0500
Subject: [PATCH 0293/2348] docs(connections): add note about
 MongoTimeoutError.reason

Fix #8402
---
 docs/connections.pug | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/docs/connections.pug b/docs/connections.pug
index b4fd6ab53d5..119619f7cdd 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -43,6 +43,7 @@ block content
       <li><a href="#connection-string-options">Connection String Options</a></li>
       <li><a href="#connection-events">Connection Events</a></li>
       <li><a href="#keepAlive">A note about keepAlive</a></li>
+      <li><a href="#server-selection">Server Selection</a></li>
       <li><a href="#replicaset_connections">Replica Set Connections</a></li>
       <li><a href="#replicaset-hostnames">Replica Set Host Names</a></li>
       <li><a href="#mongos_connections">Multi-mongos support</a></li>
@@ -279,6 +280,47 @@ block content
     mongoose.connect('mongodb://host1:port1/?replicaSet=rsName');
     ```
 
+    <h3 id="server-selection"><a href="#server-selection">Server Selection</a></h3>
+
+    If you enable the `useUnifiedTopology` option, the underlying MongoDB driver
+    will use [server selection](https://github.com/mongodb/specifications/blob/master/source/server-selection/server-selection.rst)
+    to connect to MongoDB and send operations to MongoDB. If the MongoDB
+    driver can't find a server to send an operation to after `serverSelectionTimeoutMS`,
+    you'll get the below error:
+    
+    ```
+    MongoTimeoutError: Server selection timed out after 30000 ms
+    ```
+
+    You can configure the timeout using the `serverSelectionTimeoutMS` option
+    to `mongoose.connect()`:
+
+    ```javascript
+    mongoose.connect(uri, {
+      useNewUrlParser: true,
+      useUnifiedTopology: true,
+      serverSelectionTimeoutMS: 5000 // Timeout after 5s instead of 30s
+    });
+    ```
+
+    A `MongoTimeoutError` has a `reason` property that explains why
+    server selection timed out. For example, if you're connecting to
+    a standalone server with an incorrect password, `reason`
+    will contain an "Authentication failed" error.
+
+    ```javascript
+    const mongoose = require('mongoose');
+
+    const uri = 'mongodb+srv://username:badpw@cluster0-OMITTED.mongodb.net/' +
+      'test?retryWrites=true&w=majority';
+    // Prints "MongoError: bad auth Authentication failed."
+    mongoose.connect(uri, {
+      useNewUrlParser: true,
+      useUnifiedTopology: true,
+      serverSelectionTimeoutMS: 5000
+    }).catch(err => console.log(err.reason));
+    ```
+
     <h3 id="replicaset-hostnames"><a href="#replicaset-hostnames">Replica Set Host Names</a></h3>
 
     MongoDB replica sets rely on being able to reliably figure out the domain name

From 02ec47e45cd00fc1634a0c3140130ca76a00596f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 16:42:30 -0500
Subject: [PATCH 0294/2348] test(map): add coverage for single nested maps with
 inline `_id` option

Re: #8424
Re: #8137
---
 test/types.map.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index aee37832760..782d42b0485 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -759,4 +759,23 @@ describe('Map', function() {
     const err = doc.validateSync();
     assert.ifError(err);
   });
+
+  it('maps of single nested docs with inline _id (gh-8424)', function() {
+    const childSchema = mongoose.Schema({ name: String });
+    const schema = mongoose.Schema({
+      myMap: {
+        type: Map,
+        of: {
+          type: childSchema,
+          _id: false
+        }
+      }
+    });
+    const Model = db.model('gh8424', schema);
+
+    const doc = new Model({ myMap: { foo: { name: 'bar' } } });
+
+    assert.equal(doc.myMap.get('foo').name, 'bar');
+    assert.ok(!doc.myMap.get('foo')._id);
+  });
 });

From 6cd9f6eaa066530a1c44bb84073a4d3d08758fd5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 17:26:18 -0500
Subject: [PATCH 0295/2348] test(update): repro #8444

---
 test/model.findOneAndUpdate.test.js | 34 +++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index f9bb43bb461..4e5b33675a9 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -2453,4 +2453,38 @@ describe('model: findOneAndUpdate:', function() {
     return Model.findOneAndUpdate({}, { prop: 'foo', L1: {} }, opts).lean().
       then(doc => assert.equal(doc.L1.L2.name, 'foo'));
   });
+
+  it('calls setters on mixed type (gh-8444)', function() {
+    const userSchema = new Schema({
+      jobCategory: {
+        type: Object,
+        set: () => {
+          return {
+            name: 'from setter 1',
+            value: 'from setter 2'
+          };
+        }
+      },
+      num: {
+        type: Number,
+        set: () => 42
+      }
+    });
+
+    const User = db.model('gh8444', userSchema);
+
+    return co(function*() {
+      const doc = yield User.findOneAndUpdate({}, {
+        num: 5,
+        jobCategory: {
+          name: 2,
+          value: 2
+        }
+      }, { new: true, upsert: true }).lean();
+
+      assert.equal(doc.num, 42);
+      assert.equal(doc.jobCategory.name, 'from setter 1');
+      assert.equal(doc.jobCategory.value, 'from setter 2');
+    });
+  });
 });

From b8119cff4e7e4277c52d6c08fa6394fb830becac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Dec 2019 17:26:32 -0500
Subject: [PATCH 0296/2348] fix(update): call setters when updating mixed type

Fix #8444
---
 lib/helpers/query/castUpdate.js | 4 +++-
 lib/schematype.js               | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 90a9943b7d7..0b556056c16 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -8,6 +8,7 @@ const castNumber = require('../../cast/number');
 const cast = require('../../cast');
 const getEmbeddedDiscriminatorPath = require('./getEmbeddedDiscriminatorPath');
 const handleImmutable = require('./handleImmutable');
+const schemaMixedSymbol = require('../../schema/symbols').schemaMixedSymbol;
 const utils = require('../../utils');
 
 /*!
@@ -511,7 +512,8 @@ function castUpdateVal(schema, val, op, $conditional, context, path) {
     return schema.castForQueryWrapper({
       val: val,
       context: context,
-      $skipQueryCastForUpdate: val != null && schema.$isMongooseArray && schema.$fullPath != null && !schema.$fullPath.match(/\d+$/)
+      $skipQueryCastForUpdate: val != null && schema.$isMongooseArray && schema.$fullPath != null && !schema.$fullPath.match(/\d+$/),
+      $applySetters: schema[schemaMixedSymbol] != null
     });
   }
 
diff --git a/lib/schematype.js b/lib/schematype.js
index 251231707b7..f5bda24f89e 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1352,7 +1352,7 @@ SchemaType.prototype.castForQueryWrapper = function(params) {
   if ('$conditional' in params) {
     return this.castForQuery(params.$conditional, params.val);
   }
-  if (params.$skipQueryCastForUpdate) {
+  if (params.$skipQueryCastForUpdate || params.$applySetters) {
     return this._castForQuery(params.val);
   }
   return this.castForQuery(params.val);

From f6637cf2916dedce40692eafc85ad4688e263a3f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Dec 2019 14:35:33 -0500
Subject: [PATCH 0297/2348] test(schema): repro #8450

---
 test/schema.test.js | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index eb4a532776e..3dd1639f062 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2206,6 +2206,41 @@ describe('schema', function() {
     assert.ok(doc.child._id);
   });
 
+  it('supports defining `_id: false` on document arrays (gh-8450)', function() {
+    const nestedSchema = Schema({ some: String });
+    let parentSchema = Schema({
+      arrayed: {
+        type: [{
+          type: nestedSchema,
+          _id: false
+        }]
+      }
+    });
+
+    assert.ok(!parentSchema.path('arrayed').schema.path('_id'));
+
+    parentSchema = Schema({
+      arrayed: {
+        type: [{
+          type: nestedSchema
+        }],
+        _id: false
+      }
+    });
+
+    assert.ok(!parentSchema.path('arrayed').schema.path('_id'));
+
+    parentSchema = Schema({
+      arrayed: {
+        type: [{
+          type: nestedSchema
+        }]
+      }
+    });
+
+    assert.ok(parentSchema.path('arrayed').schema.path('_id').auto);
+  });
+
   describe('pick() (gh-8207)', function() {
     it('works with nested paths', function() {
       const schema = Schema({

From 766e06e126459094bca1cf4659093af115ce6c95 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Dec 2019 14:35:53 -0500
Subject: [PATCH 0298/2348] fix(schema): handle `_id` option for document array
 schematypes

Fix #8450
---
 lib/helpers/schema/handleIdOption.js      | 20 ++++++++++++++++++++
 lib/options/SchemaDocumentArrayOptions.js | 20 ++++++++++++++++++++
 lib/schema/SingleNestedPath.js            | 13 ++-----------
 lib/schema/documentarray.js               |  7 +++++++
 4 files changed, 49 insertions(+), 11 deletions(-)
 create mode 100644 lib/helpers/schema/handleIdOption.js

diff --git a/lib/helpers/schema/handleIdOption.js b/lib/helpers/schema/handleIdOption.js
new file mode 100644
index 00000000000..569bf9f51b1
--- /dev/null
+++ b/lib/helpers/schema/handleIdOption.js
@@ -0,0 +1,20 @@
+'use strict';
+
+const addAutoId = require('./addAutoId');
+
+module.exports = function handleIdOption(schema, options) {
+  if (options == null || options._id == null) {
+    return schema;
+  }
+
+  schema = schema.clone();
+  if (!options._id) {
+    schema.remove('_id');
+    schema.options._id = false;
+  } else if (!schema.paths['_id']) {
+    addAutoId(schema);
+    schema.options._id = true;
+  }
+
+  return schema;
+};
\ No newline at end of file
diff --git a/lib/options/SchemaDocumentArrayOptions.js b/lib/options/SchemaDocumentArrayOptions.js
index 2283616388c..f3fb7a9777e 100644
--- a/lib/options/SchemaDocumentArrayOptions.js
+++ b/lib/options/SchemaDocumentArrayOptions.js
@@ -41,6 +41,26 @@ const opts = require('./propertyOptions');
 
 Object.defineProperty(SchemaDocumentArrayOptions.prototype, 'excludeIndexes', opts);
 
+/**
+ * If set, overwrites the child schema's `_id` option.
+ *
+ * ####Example:
+ *
+ *     const childSchema = Schema({ name: String });
+ *     const parentSchema = Schema({
+ *       child: { type: childSchema, _id: false }
+ *     });
+ *     parentSchema.path('child').schema.options._id; // false
+ *
+ * @api public
+ * @property _id
+ * @memberOf SchemaDocumentArrayOptions
+ * @type Array
+ * @instance
+ */
+
+Object.defineProperty(SchemaDocumentArrayOptions.prototype, '_id', opts);
+
 /*!
  * ignore
  */
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index b5baac63c38..a33d65bf74c 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -10,12 +10,12 @@ const ObjectExpectedError = require('../error/objectExpected');
 const SchemaSingleNestedOptions = require('../options/SchemaSingleNestedOptions');
 const SchemaType = require('../schematype');
 const $exists = require('./operators/exists');
-const addAutoId = require('../helpers/schema/addAutoId');
 const castToNumber = require('./operators/helpers').castToNumber;
 const discriminator = require('../helpers/model/discriminator');
 const geospatial = require('./operators/geospatial');
 const get = require('../helpers/get');
 const getConstructor = require('../helpers/discriminator/getConstructor');
+const handleIdOption = require('../helpers/schema/handleIdOption');
 const internalToObjectOptions = require('../options').internalToObjectOptions;
 
 let Subdocument;
@@ -33,16 +33,7 @@ module.exports = SingleNestedPath;
  */
 
 function SingleNestedPath(schema, path, options) {
-  if (options != null && options._id != null) {
-    schema = schema.clone();
-    if (!options._id) {
-      schema.remove('_id');
-      schema.options._id = false;
-    } else if (!schema.paths['_id']) {
-      addAutoId(schema);
-      schema.options._id = true;
-    }
-  }
+  schema = handleIdOption(schema, options);
 
   this.caster = _createConstructor(schema);
   this.caster.path = path;
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 28d4a4b1a82..49733ac9863 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -12,6 +12,7 @@ const SchemaDocumentArrayOptions =
 const SchemaType = require('../schematype');
 const discriminator = require('../helpers/model/discriminator');
 const get = require('../helpers/get');
+const handleIdOption = require('../helpers/schema/handleIdOption');
 const util = require('util');
 const utils = require('../utils');
 const getConstructor = require('../helpers/discriminator/getConstructor');
@@ -33,6 +34,12 @@ let Subdocument;
  */
 
 function DocumentArrayPath(key, schema, options, schemaOptions) {
+  if (schemaOptions != null && schemaOptions._id != null) {
+    schema = handleIdOption(schema, schemaOptions);
+  } else if (options != null && options._id != null) {
+    schema = handleIdOption(schema, options);
+  }
+
   const EmbeddedDocument = _createConstructor(schema, options);
   EmbeddedDocument.prototype.$basePath = key;
 

From d3a29be29569f0c14969071a42178f7b03065dcc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Dec 2019 21:07:43 -0500
Subject: [PATCH 0299/2348] docs(schematypes): add `enum` to list of schema
 number options

---
 docs/schematypes.pug | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index bef5b8ab2ee..b79b157415b 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -287,6 +287,7 @@ block content
 
     * `min`: Number, creates a [validator](./validation.html) that checks if the value is greater than or equal to the given minimum.
     * `max`: Number, creates a [validator](./validation.html) that checks if the value is less than or equal to the given maximum.
+    * `enum`: Array, creates a [validator](./validation.html) that checks if the value is strictly equal to one of the values in the given array.
 
     <h5>Date</h5>
 

From ded973d86b942ae8c8d104feb3757f18339d7144 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Dec 2019 13:56:25 -0500
Subject: [PATCH 0300/2348] chore: release 5.8.3

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index ae4f7ed796b..f67622ff009 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.8.3 / 2019-12-23
+==================
+ * fix: upgrade mongodb -> 3.4.1 #8430 [jaschaio](https://github.com/jaschaio)
+ * fix(populate): don't add empty subdocument to array when populating path underneath a non-existent document array #8432
+ * fix(schema): handle `_id` option for document array schematypes #8450
+ * fix(update): call setters when updating mixed type #8444
+ * docs(connections): add note about MongoTimeoutError.reason #8402
+
 5.8.2 / 2019-12-20
 ==================
  * fix(schema): copy `.add()`-ed paths when calling `.add()` with schema argument #8429
diff --git a/package.json b/package.json
index a9f65c294d3..931967ebbde 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.3-pre",
+  "version": "5.8.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 979fb8775e2991ea577b1d973567b4ee6c1a7eb2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Dec 2019 14:03:34 -0500
Subject: [PATCH 0301/2348] chore: add monetta as opencollective sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 85e641a77e3..4ea95c3d996 100644
--- a/index.pug
+++ b/index.pug
@@ -271,6 +271,9 @@ html(lang='en')
               <a href="https://uk.edubirdie.com/">
                 <img class="sponsor" src="https://images.opencollective.com/uk-edubirdie-com/b1d51ab/logo.png" style="height: 100px">
               </a>
+              <a href="https://www.monetta.pl/">
+                <img class="sponsor" src="https://images.opencollective.com/monetta/7d65ae6/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 7fae539c64a8d91364daade4090875068cf1f6f6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 24 Dec 2019 10:46:23 -0500
Subject: [PATCH 0302/2348] docs: add example to SchemaNumberOptions#enum

---
 lib/options/SchemaNumberOptions.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index c9b4c709e82..8ecc88988ef 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -48,6 +48,15 @@ Object.defineProperty(SchemaNumberOptions.prototype, 'max', opts);
 /**
  * If set, Mongoose adds a validator that checks that this path is strictly
  * equal to one of the given values.
+ * 
+ * ####Example:
+ *     const schema = new Schema({
+ *       favoritePrime: {
+ *         type: Number,
+ *         enum: [3, 5, 7]
+ *       }
+ *     });
+ *     schema.path('favoritePrime').options.enum; // [3, 5, 7]
  *
  * @api public
  * @property enum

From 9ec7949cba1802b443e449a8deb0c2966b103c82 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Dec 2019 11:01:07 -0500
Subject: [PATCH 0303/2348] fix(connection): wrap `mongoose.connect()` server
 selection timeouts in MongooseTimeoutError for more readable stack traces

Fix #8451
---
 lib/connection.js       |  6 ++++++
 lib/error/timeout.js    | 13 +++++++++++++
 lib/model.js            |  4 +---
 package.json            |  2 +-
 test/connection.test.js | 14 ++++++++++++++
 5 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 3fe42ff9c2c..b2bf74d59f8 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -10,6 +10,7 @@ const Collection = require('./driver').get().Collection;
 const STATES = require('./connectionstate');
 const MongooseError = require('./error/index');
 const PromiseProvider = require('./promise_provider');
+const TimeoutError = require('./error/timeout');
 const applyPlugins = require('./helpers/schema/applyPlugins');
 const get = require('./helpers/get');
 const mongodb = require('mongodb');
@@ -759,9 +760,14 @@ Connection.prototype.openUri = function(uri, options, callback) {
     });
   });
 
+  const timeout = new TimeoutError();
   this.$initialConnection = Promise.all([promise, parsePromise]).
     then(res => res[0]).
     catch(err => {
+      if (err != null && err.name === 'MongoTimeoutError') {
+        err = timeout.assimilateError(err);
+      }
+
       if (this.listeners('error').length > 0) {
         process.nextTick(() => this.emit('error', err));
       }
diff --git a/lib/error/timeout.js b/lib/error/timeout.js
index f35f08f55e1..4f15d9038bc 100644
--- a/lib/error/timeout.js
+++ b/lib/error/timeout.js
@@ -32,4 +32,17 @@ function MongooseTimeoutError(message) {
 MongooseTimeoutError.prototype = Object.create(MongooseError.prototype);
 MongooseTimeoutError.prototype.constructor = MongooseError;
 
+/*!
+ * ignore
+ */
+
+MongooseTimeoutError.prototype.assimilateError = function(err) {
+  this.message = err.message;
+  Object.assign(this, err, {
+    name: 'MongooseTimeoutError'
+  });
+
+  return this;
+};
+
 module.exports = MongooseTimeoutError;
diff --git a/lib/model.js b/lib/model.js
index 88eff90b945..b45263f7b42 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4779,9 +4779,7 @@ Model.$wrapCallback = function(callback) {
 
   return function(err) {
     if (err != null && err.name === 'MongoTimeoutError') {
-      arguments[0] = timeout;
-      timeout.message = err.message;
-      Object.assign(timeout, err);
+      arguments[0] = timeout.assimilateError(err);
     }
 
     return callback.apply(null, arguments);
diff --git a/package.json b/package.json
index 931967ebbde..968c0ae5ae5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.3",
+  "version": "5.8.4-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",
diff --git a/test/connection.test.js b/test/connection.test.js
index 47e4b30cb58..f409b01ba1f 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1146,4 +1146,18 @@ describe('connections:', function() {
     assert.ok(Model);
     return Model.create({ name: 'test' });
   });
+
+  it('throws a MongooseTimeoutError on server selection timeout (gh-8451)', () => {
+    const opts = {
+      useNewUrlParser: true,
+      useUnifiedTopology: true,
+      serverSelectionTimeoutMS: 100
+    };
+    const uri = 'mongodb://baddomain:27017/test';
+
+    return mongoose.createConnection(uri, opts).then(() => assert.ok(false), err => {
+      assert.equal(err.message, 'Server selection timed out after 100 ms');
+      assert.equal(err.name, 'MongooseTimeoutError');
+    });
+  });
 });

From e350e6a973170d88a1636a6a0067daa514fd6dae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Dec 2019 12:51:09 -0500
Subject: [PATCH 0304/2348] fix(array): allow defining `enum` on array if an
 array of numbers

Analagous to #6102 but for arrays of numbers
Re: #8139

Fix #6102
---
 lib/options/SchemaNumberOptions.js |  2 +-
 lib/schema/array.js                | 11 +++++-----
 test/schema.validation.test.js     | 32 ++++++++++++++++++++----------
 3 files changed, 29 insertions(+), 16 deletions(-)

diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index 8ecc88988ef..42b0a01583d 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -48,7 +48,7 @@ Object.defineProperty(SchemaNumberOptions.prototype, 'max', opts);
 /**
  * If set, Mongoose adds a validator that checks that this path is strictly
  * equal to one of the given values.
- * 
+ *
  * ####Example:
  *     const schema = new Schema({
  *       favoritePrime: {
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 5b34182c416..e32cff9bfc5 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -190,11 +190,11 @@ SchemaArray.prototype.checkRequired = function checkRequired(value, doc) {
 };
 
 /**
- * Adds an enum validator if this is an array of strings. Equivalent to
- * `SchemaString.prototype.enum()`
+ * Adds an enum validator if this is an array of strings or numbers. Equivalent to
+ * `SchemaString.prototype.enum()` or `SchemaNumber.prototype.enum()`
  *
  * @param {String|Object} [args...] enumeration values
- * @return {SchemaType} this
+ * @return {SchemaArray} this
  */
 
 SchemaArray.prototype.enum = function() {
@@ -205,8 +205,9 @@ SchemaArray.prototype.enum = function() {
       arr = arr.caster;
       continue;
     }
-    if (instance !== 'String') {
-      throw new Error('`enum` can only be set on an array of strings, not ' + instance);
+    if (instance !== 'String' && instance !== 'Number') {
+      throw new Error('`enum` can only be set on an array of strings or numbers ' +
+        ', not ' + instance);
     }
     break;
   }
diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index 6b689ef052a..570b6e48660 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -1253,29 +1253,41 @@ describe('schema', function() {
       });
     });
 
-    it('enums on arrays (gh-6102)', function() {
+    it('enums on arrays (gh-6102) (gh-8449)', function() {
       assert.throws(function() {
         new Schema({
           array: {
-            type: [Number],
-            enum: [1]
+            type: [Boolean],
+            enum: [true]
           }
         });
-      }, /`enum` can only be set on an array of strings/);
+      }, /`enum` can only be set on an array of strings or numbers/);
 
-      const MySchema = new Schema({
+      let MySchema = new Schema({
         array: {
           type: [String],
           enum: ['qwerty']
         }
       });
 
-      const Model = mongoose.model('gh6102', MySchema);
-      const doc = new Model({ array: ['test'] });
+      let Model = mongoose.model('gh6102', MySchema);
+      const doc1 = new Model({ array: ['test'] });
 
-      return doc.validate().
-        then(() => assert.ok(false)).
-        catch(err => assert.equal(err.name, 'ValidationError'));
+      MySchema = new Schema({
+        array: {
+          type: [Number],
+          enum: [3, 5, 7]
+        }
+      });
+
+      mongoose.deleteModel('gh6102');
+      Model = mongoose.model('gh6102', MySchema);
+      const doc2 = new Model({ array: [1, 2, 3] });
+
+      return doc1.validate().
+        then(() => assert.ok(false), err => assert.equal(err.name, 'ValidationError')).
+        then(() => doc2.validate()).
+        then(() => assert.ok(false), err => assert.equal(err.name, 'ValidationError'));
     });
 
     it('skips conditional required (gh-3539)', function(done) {

From 9cb0dde4507afb33bab913650d1be9ded4e4d620 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Dec 2019 10:42:05 -0500
Subject: [PATCH 0305/2348] test(populate): repro #8455

---
 test/model.populate.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 1b36644aae4..6e49e435d5f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8932,4 +8932,27 @@ describe('model: populate:', function() {
       assert.deepEqual(populatedRides[1].files, []);
     });
   });
+
+  it('sets empty array if populating undefined path (gh-8455)', function() {
+    const TestSchema = new Schema({
+      thingIds: [mongoose.ObjectId]
+    });
+    
+    TestSchema.virtual('things', {
+      ref: 'gh8455_Thing',
+      localField: 'thingIds',
+      foreignField: '_id',
+      justOne: false
+    });
+    
+    const Test = db.model('gh8455_Test', TestSchema);
+    const Thing = db.model('gh8455_Thing', mongoose.Schema({ name: String }));
+
+    return co(function*() {
+      yield Test.collection.insertOne({});
+
+      const doc = yield Test.findOne().populate('things');
+      assert.deepEqual(doc.toObject({ virtuals: true }).things, []);
+    });
+  });
 });

From ded087187df365524fdc4f30867fb970b2e9d296 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Dec 2019 10:42:18 -0500
Subject: [PATCH 0306/2348] fix(populate): ensure populate virtual gets set to
 empty array if `localField` is undefined in the database

Fix #8455
Re: #8432
---
 lib/helpers/populate/assignVals.js              |  9 +++++++++
 lib/helpers/populate/getModelsMapForPopulate.js | 10 +++-------
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 9d2edfb7f6c..a033e8d3ee1 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -90,13 +90,22 @@ module.exports = function assignVals(o) {
 
     const parts = o.path.split('.');
     let cur = docs[i];
+    let curPath = parts[0];
     for (let j = 0; j < parts.length - 1; ++j) {
       // If we get to an array with a dotted path, like `arr.foo`, don't set
       // `foo` on the array.
       if (Array.isArray(cur) && !utils.isArrayIndex(parts[j])) {
         break;
       }
+
       if (cur[parts[j]] == null) {
+        // If nothing to set, avoid creating an unnecessary array. Otherwise
+        // we'll end up with a single doc in the array with only defaults.
+        // See gh-8342, gh-8455
+        const schematype = originalSchema._getSchema(curPath);
+        if (valueToSet === void 0 && schematype != null && schematype.$isMongooseArray) {
+          return;
+        }
         cur[parts[j]] = {};
       }
       cur = cur[parts[j]];
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index cdd407dfc3b..50b027d0e4d 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -172,10 +172,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       ret = convertTo_id(utils.getValue(localField, doc), schema);
     }
 
-    if (ret === undefined) {
-      continue;
-    }
-
     const id = String(utils.getValue(foreignField, doc));
     options._docs[id] = Array.isArray(ret) ? ret.slice() : ret;
 
@@ -232,8 +228,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           options: currentOptions,
           match: hasMatchFunction ? [match] : match,
           docs: [doc],
-          ids: [ids],
-          allIds: [ret],
+          ids: ids === void 0 ? [] : [ids],
+          allIds: ret === void 0 ? [] : [ret],
           localField: new Set([localField]),
           foreignField: new Set([foreignField]),
           justOne: justOne,
@@ -243,7 +239,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           [populateModelSymbol]: Model
         };
         map.push(available[modelName]);
-      } else {
+      } else if (ret !== void 0) {
         available[modelName].localField.add(localField);
         available[modelName].foreignField.add(foreignField);
         available[modelName].docs.push(doc);

From 392e2b156bf80643930725e2f1565d87e4a74c08 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Dec 2019 10:43:51 -0500
Subject: [PATCH 0307/2348] style: fix lint

---
 lib/helpers/populate/assignVals.js | 2 +-
 test/model.populate.test.js        | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index a033e8d3ee1..ee2b05ac2b7 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -90,7 +90,7 @@ module.exports = function assignVals(o) {
 
     const parts = o.path.split('.');
     let cur = docs[i];
-    let curPath = parts[0];
+    const curPath = parts[0];
     for (let j = 0; j < parts.length - 1; ++j) {
       // If we get to an array with a dotted path, like `arr.foo`, don't set
       // `foo` on the array.
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6e49e435d5f..5948fc2c0b6 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8937,16 +8937,16 @@ describe('model: populate:', function() {
     const TestSchema = new Schema({
       thingIds: [mongoose.ObjectId]
     });
-    
+
     TestSchema.virtual('things', {
       ref: 'gh8455_Thing',
       localField: 'thingIds',
       foreignField: '_id',
       justOne: false
     });
-    
+
     const Test = db.model('gh8455_Test', TestSchema);
-    const Thing = db.model('gh8455_Thing', mongoose.Schema({ name: String }));
+    db.model('gh8455_Thing', mongoose.Schema({ name: String }));
 
     return co(function*() {
       yield Test.collection.insertOne({});

From 7384bddfa9dfd53fbd59fa88bb5329065ddcfc4d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Dec 2019 10:58:02 -0500
Subject: [PATCH 0308/2348] test: fix broken test re: #8455

---
 lib/helpers/populate/getModelsMapForPopulate.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 50b027d0e4d..d2c3e449672 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -228,8 +228,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           options: currentOptions,
           match: hasMatchFunction ? [match] : match,
           docs: [doc],
-          ids: ids === void 0 ? [] : [ids],
-          allIds: ret === void 0 ? [] : [ret],
+          ids: [ids],
+          allIds: [ret],
           localField: new Set([localField]),
           foreignField: new Set([foreignField]),
           justOne: justOne,
@@ -239,7 +239,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           [populateModelSymbol]: Model
         };
         map.push(available[modelName]);
-      } else if (ret !== void 0) {
+      } else {
         available[modelName].localField.add(localField);
         available[modelName].foreignField.add(foreignField);
         available[modelName].docs.push(doc);

From 770df18c57bb74efbb6bc250a7f620e943361305 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Dec 2019 11:04:53 -0500
Subject: [PATCH 0309/2348] fix: fix test for #8432 re: #8455

---
 lib/helpers/populate/assignVals.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index ee2b05ac2b7..a7a98ad349f 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -103,7 +103,7 @@ module.exports = function assignVals(o) {
         // we'll end up with a single doc in the array with only defaults.
         // See gh-8342, gh-8455
         const schematype = originalSchema._getSchema(curPath);
-        if (valueToSet === void 0 && schematype != null && schematype.$isMongooseArray) {
+        if (valueToSet == null && schematype != null && schematype.$isMongooseArray) {
           return;
         }
         cur[parts[j]] = {};

From f27fb82f88c986e2ce499a5ffefeb1a58f320d22 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jan 2020 17:24:01 -0500
Subject: [PATCH 0310/2348] test(populate): repro #8452

---
 test/model.populate.test.js | 44 +++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5948fc2c0b6..a4bd68b2259 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8955,4 +8955,48 @@ describe('model: populate:', function() {
       assert.deepEqual(doc.toObject({ virtuals: true }).things, []);
     });
   });
+
+  it('succeeds with refPath if embedded discriminator has path with same name but no refPath (gh-8452)', function() {
+    const ImageSchema = Schema({ imageName: String });
+    const Image = db.model('gh8452_Image', ImageSchema);
+  
+    const TextSchema = Schema({ textName: String });
+    const Text = db.model('gh8452_Text', TextSchema);
+  
+    const opts = { _id: false };
+    const ItemSchema = Schema({ objectType: String }, opts);
+    const ItemSchemaA = Schema({
+      data: { 
+        type: ObjectId,
+        refPath: 'list.objectType'
+      },
+      objectType: String,
+    }, opts);
+    const ItemSchemaB = Schema({
+      data: { sourceId: Number },
+      objectType: String,
+    }, opts);
+  
+    const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
+    ExampleSchema.path('list').discriminator('gh8452_ExtendA', ItemSchemaA);
+    ExampleSchema.path('list').discriminator('gh8452_ExtendB', ItemSchemaB);
+    const Example = db.model('gh8452_Example', ExampleSchema);
+
+    return co(function*() {
+      const image = yield Image.create({ imageName: 'image' });
+      const text = yield Text.create({ textName: 'text' });
+      yield Example.create({
+        test: '02',
+        list: [
+          { __t: 'gh8452_ExtendA', data: image._id, objectType: 'gh8452_Image' },
+          { __t: 'gh8452_ExtendA', data: text._id, objectType: 'gh8452_Text' },
+          { __t: 'gh8452_ExtendB', data: { sourceId: 123 }, objectType: 'ExternalSourceA' }
+        ]
+      });
+
+      const res = yield Example.findOne().populate('list.data').lean();
+      assert.equal(res.list[0].data.imageName, 'image');
+      assert.equal(res.list[1].data.textName, 'text');
+    });
+  });
 });

From 3f776a44898b466ce79618dfc4695f7600627b28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jan 2020 17:25:47 -0500
Subject: [PATCH 0311/2348] fix(populate): support embedded discriminators with
 `refPath` when not all discriminator schemas have `refPath`

Fix #8452
---
 .../populate/getModelsMapForPopulate.js       | 43 ++++++++++++++++++-
 test/model.populate.test.js                   |  1 +
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index d2c3e449672..c1a38189252 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -45,6 +45,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
     modelNames = null;
     let isRefPath = false;
+    let normalizedRefPath = null;
     if (Array.isArray(schema)) {
       for (let j = 0; j < schema.length; ++j) {
         let _modelNames;
@@ -52,6 +53,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           const res = _getModelNames(doc, schema[j]);
           _modelNames = res.modelNames;
           isRefPath = res.isRefPath;
+          normalizedRefPath = res.refPath;
         } catch (error) {
           return error;
         }
@@ -70,6 +72,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         const res = _getModelNames(doc, schema);
         modelNames = res.modelNames;
         isRefPath = res.isRefPath;
+        normalizedRefPath = res.refPath;
       } catch (error) {
         return error;
       }
@@ -184,6 +187,41 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       match = match.call(doc, doc);
     }
 
+    // Re: gh-8452. Embedded discriminators may not have `refPath`, so clear
+    // out embedded discriminator docs that don't have a `refPath` on the
+    // populated path.
+    if (isRefPath) {
+      const pieces = normalizedRefPath.split('.');
+      let cur = '';
+      for (let i = 0; i < pieces.length; ++i) {
+        cur = cur + (cur.length === 0 ? '' : '.') + pieces[i];
+        const schematype = modelSchema.path(cur);
+        if (schematype != null &&
+            schematype.$isMongooseArray &&
+            schematype.caster.discriminators != null &&
+            Object.keys(schematype.caster.discriminators).length > 0) {
+          const subdocs = utils.getValue(cur, doc);
+          const remnant = options.path.substr(cur.length + 1);
+          const discriminatorKey = schematype.caster.schema.options.discriminatorKey;
+          modelNames = [];
+          for (const subdoc of subdocs) {
+            const discriminatorValue = utils.getValue(discriminatorKey, subdoc);
+            const discriminatorSchema = schematype.caster.discriminators[discriminatorValue].schema;
+            if (discriminatorSchema == null) {
+              continue;
+            }
+            const _path = discriminatorSchema.path(remnant);
+            if (_path == null || _path.options.refPath == null) {
+              const docValue = utils.getValue(localField.substr(cur.length + 1), subdoc);
+              ret = ret.filter(v => v !== docValue);
+              continue;
+            }
+            modelNames.push(utils.getValue(pieces.slice(i + 1).join('.'), subdoc));
+          }
+        }
+      }
+    }
+
     let k = modelNames.length;
     while (k--) {
       modelName = modelNames[k];
@@ -205,6 +243,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
       let ids = ret;
       const flat = Array.isArray(ret) ? utils.array.flatten(ret) : [];
+
       if (isRefPath && Array.isArray(ret) && flat.length === modelNames.length) {
         ids = flat.filter((val, i) => modelNames[i] === modelName);
       }
@@ -356,14 +395,14 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     }
 
     if (!modelNames) {
-      return { modelNames: modelNames, isRefPath: isRefPath };
+      return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath };
     }
 
     if (!Array.isArray(modelNames)) {
       modelNames = [modelNames];
     }
 
-    return { modelNames: modelNames, isRefPath: isRefPath };
+    return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath };
   }
 
   return map;
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a4bd68b2259..260c6983231 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8997,6 +8997,7 @@ describe('model: populate:', function() {
       const res = yield Example.findOne().populate('list.data').lean();
       assert.equal(res.list[0].data.imageName, 'image');
       assert.equal(res.list[1].data.textName, 'text');
+      assert.equal(res.list[2].data.sourceId, 123);
     });
   });
 });

From 9ce579eaec9ee0d372816de432d908cb5905de61 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jan 2020 17:28:42 -0500
Subject: [PATCH 0312/2348] style: fix lint

---
 test/model.populate.test.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 260c6983231..4314cc4626d 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8959,14 +8959,14 @@ describe('model: populate:', function() {
   it('succeeds with refPath if embedded discriminator has path with same name but no refPath (gh-8452)', function() {
     const ImageSchema = Schema({ imageName: String });
     const Image = db.model('gh8452_Image', ImageSchema);
-  
+
     const TextSchema = Schema({ textName: String });
     const Text = db.model('gh8452_Text', TextSchema);
-  
+
     const opts = { _id: false };
     const ItemSchema = Schema({ objectType: String }, opts);
     const ItemSchemaA = Schema({
-      data: { 
+      data: {
         type: ObjectId,
         refPath: 'list.objectType'
       },
@@ -8976,7 +8976,7 @@ describe('model: populate:', function() {
       data: { sourceId: Number },
       objectType: String,
     }, opts);
-  
+
     const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
     ExampleSchema.path('list').discriminator('gh8452_ExtendA', ItemSchemaA);
     ExampleSchema.path('list').discriminator('gh8452_ExtendB', ItemSchemaB);

From 98724becf41c580d77ed65d769952d04c6ff689b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jan 2020 17:29:51 -0500
Subject: [PATCH 0313/2348] test: fix tests re: #8452

---
 lib/helpers/populate/getModelsMapForPopulate.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index c1a38189252..07e44587d77 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -190,7 +190,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     // Re: gh-8452. Embedded discriminators may not have `refPath`, so clear
     // out embedded discriminator docs that don't have a `refPath` on the
     // populated path.
-    if (isRefPath) {
+    if (isRefPath && normalizedRefPath != null) {
       const pieces = normalizedRefPath.split('.');
       let cur = '';
       for (let i = 0; i < pieces.length; ++i) {

From b6f6f3740ce9b14a43eec24c32a6a8fc306c26fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jan 2020 12:57:11 -0500
Subject: [PATCH 0314/2348] test(populate): repro #8460

---
 test/model.populate.test.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 4314cc4626d..9ffea3e0027 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9000,4 +9000,36 @@ describe('model: populate:', function() {
       assert.equal(res.list[2].data.sourceId, 123);
     });
   });
+
+  it('excluding foreignField using minus path deselects foreignField (gh-8460)', function() {
+    const schema = Schema({ specialId: String });
+
+    schema.virtual('searchResult', {
+      ref: 'gh8460_Result',
+      localField: 'specialId',
+      foreignField: 'specialId',
+      options: { select: 'name -_id -specialId' },
+      justOne: true
+    });
+    const Model = db.model('gh8460_Model', schema);
+    const Result = db.model('gh8460_Result', Schema({
+      name: String,
+      specialId: String,
+      other: String
+    }));
+
+    return co(function*() {
+      yield Result.create({ name: 'foo', specialId: 'secret', other: 'test' });
+      yield Model.create({ specialId: 'secret' });
+  
+      let doc = yield Model.findOne().populate('searchResult');
+      assert.strictEqual(doc.searchResult.specialId, void 0);
+
+      doc = yield Model.findOne().populate({
+        path: 'searchResult',
+        select: 'name -_id'
+      });
+      assert.strictEqual(doc.searchResult.specialId, 'secret');
+    });
+  });
 });

From 9261d9d0a5667f36123c9e5ab5fb0479e6148944 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jan 2020 12:57:29 -0500
Subject: [PATCH 0315/2348] fix(populate): allow deselecting `foreignField`
 from projection by prefixing with `-`

Fix #8460
Fix mongodb-js/mongoose-autopopulate#60
---
 lib/helpers/projection/parseProjection.js | 33 +++++++++++++++++++++++
 lib/model.js                              | 16 ++++++++++-
 lib/query.js                              | 20 +++-----------
 3 files changed, 51 insertions(+), 18 deletions(-)
 create mode 100644 lib/helpers/projection/parseProjection.js

diff --git a/lib/helpers/projection/parseProjection.js b/lib/helpers/projection/parseProjection.js
new file mode 100644
index 00000000000..d2a44b10653
--- /dev/null
+++ b/lib/helpers/projection/parseProjection.js
@@ -0,0 +1,33 @@
+'use strict';
+
+/**
+ * Convert a string or array into a projection object, retaining all
+ * `-` and `+` paths.
+ */
+
+module.exports = function parseProjection(v, retainMinusPaths) {
+  const type = typeof v;
+
+  if (type === 'string') {
+    v = v.split(/\s+/);
+  }
+  if (!Array.isArray(v) && Object.prototype.toString.call(v) !== '[object Arguments]') {
+    return v;
+  }
+
+  const len = v.length;
+  const ret = {};
+  for (let i = 0; i < len; ++i) {
+    let field = v[i];
+    if (!field) {
+      continue;
+    }
+    const include = '-' == field[0] ? 0 : 1;
+    if (!retainMinusPaths && include === 0) {
+      field = field.substring(1);
+    }
+    ret[field] = include;
+  }
+
+  return ret;
+};
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index b45263f7b42..a038df6d34c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -40,7 +40,9 @@ const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedIncl
 const get = require('./helpers/get');
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
 const modifiedPaths = require('./helpers/update/modifiedPaths');
+const mpath = require('mpath');
 const parallelLimit = require('./helpers/parallelLimit');
+const parseProjection = require('./helpers/projection/parseProjection');
 const util = require('util');
 const utils = require('./utils');
 
@@ -4418,7 +4420,9 @@ function _assign(model, vals, mod, assignmentOpts) {
   const isVirtual = mod.isVirtual;
   const justOne = mod.justOne;
   let _val;
-  const lean = options.options && options.options.lean;
+  const lean = get(options, 'options.lean', false);
+  const projection = parseProjection(get(options, 'select', null), true) ||
+    parseProjection(get(options, 'options.select', null), true);
   const len = vals.length;
   const rawOrder = {};
   const rawDocs = {};
@@ -4489,6 +4493,16 @@ function _assign(model, vals, mod, assignmentOpts) {
       } else {
         val.$__.wasPopulated = true;
       }
+
+      // gh-8460: if user used `-foreignField`, assume this means they
+      // want the foreign field unset even if it isn't excluded in the query.
+      if (projection != null && projection.hasOwnProperty('-' + foreignField)) {
+        if (val.$__ != null) {
+          val.set(foreignField, void 0);
+        } else {
+          mpath.unset(foreignField, val);
+        }
+      }
     }
   }
 
diff --git a/lib/query.js b/lib/query.js
index 40447f60522..250b37d9557 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -23,6 +23,7 @@ const hasDollarKeys = require('./helpers/query/hasDollarKeys');
 const helpers = require('./queryhelpers');
 const isInclusive = require('./helpers/projection/isInclusive');
 const mquery = require('mquery');
+const parseProjection = require('./helpers/projection/parseProjection');
 const selectPopulatedFields = require('./helpers/query/selectPopulatedFields');
 const setDefaultsOnInsert = require('./helpers/setDefaultsOnInsert');
 const slice = require('sliced');
@@ -951,23 +952,8 @@ Query.prototype.select = function select() {
 
   const fields = this._fields || (this._fields = {});
   const userProvidedFields = this._userProvidedFields || (this._userProvidedFields = {});
-  const type = typeof arg;
-
-  if (('string' == type || Object.prototype.toString.call(arg) === '[object Arguments]') &&
-    'number' == typeof arg.length || Array.isArray(arg)) {
-    if ('string' == type)
-      arg = arg.split(/\s+/);
-
-    for (i = 0, len = arg.length; i < len; ++i) {
-      let field = arg[i];
-      if (!field) continue;
-      const include = '-' == field[0] ? 0 : 1;
-      if (include === 0) field = field.substring(1);
-      fields[field] = include;
-      userProvidedFields[field] = include;
-    }
-    return this;
-  }
+
+  arg = parseProjection(arg);
 
   if (utils.isObject(arg)) {
     const keys = Object.keys(arg);

From 0729b23f0f420fa94a464ecccd882e24debea21d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jan 2020 14:38:33 -0500
Subject: [PATCH 0316/2348] style: fix lint

---
 lib/query.js                | 1 -
 test/model.populate.test.js | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 250b37d9557..6837516aa36 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -942,7 +942,6 @@ Query.prototype.select = function select() {
   let arg = arguments[0];
   if (!arg) return this;
   let i;
-  let len;
 
   if (arguments.length !== 1) {
     throw new Error('Invalid select: select only takes 1 argument');
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 9ffea3e0027..60af45542b4 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9021,7 +9021,7 @@ describe('model: populate:', function() {
     return co(function*() {
       yield Result.create({ name: 'foo', specialId: 'secret', other: 'test' });
       yield Model.create({ specialId: 'secret' });
-  
+
       let doc = yield Model.findOne().populate('searchResult');
       assert.strictEqual(doc.searchResult.specialId, void 0);
 

From f89a67b32337d16940544c95ad4b545e7e2187b2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jan 2020 16:31:54 -0500
Subject: [PATCH 0317/2348] docs(model): clean up some docs re: `aggregate()`

---
 lib/model.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index a038df6d34c..5593b76f11a 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3885,9 +3885,8 @@ Model.mapReduce = function mapReduce(o, callback) {
  *
  * ####NOTE:
  *
- * - Arguments are not cast to the model's schema because `$project` operators allow redefining the "shape" of the documents at any stage of the pipeline, which may leave documents in an incompatible format.
+ * - Mongoose does **not** cast aggregation pipelines to the model's schema because `$project` and `$group` operators allow redefining the "shape" of the documents at any stage of the pipeline, which may leave documents in an incompatible format. You can use the [mongoose-cast-aggregation plugin](https://github.com/AbdelrahmanHafez/mongoose-cast-aggregation) to enable minimal casting for aggregation pipelines.
  * - The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).
- * - Requires MongoDB >= 2.1
  *
  * @see Aggregate #aggregate_Aggregate
  * @see MongoDB http://docs.mongodb.org/manual/applications/aggregation/

From ae80b5bff2cfa67d6ca2a0f99c62227a753522da Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jan 2020 16:33:06 -0500
Subject: [PATCH 0318/2348] chore: update opencollective sponsors

---
 index.pug | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.pug b/index.pug
index 4ea95c3d996..26c8369370c 100644
--- a/index.pug
+++ b/index.pug
@@ -202,9 +202,6 @@ html(lang='en')
               <a href="https://uiuxagencies.top/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F62223ab0-f4f7-11e8-919f-53f2ea21a967.png&height=100" style="height:100px">
               </a>
-              <a href="https://www.promocodewatch.com/">
-                <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fbd0053f0-4f64-11e9-8022-91853c58485e.png&height=100" style="height:100px">
-              </a>
               <a href="https://www.vpnranks.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fvpnranks.com&height=100" style="height:100px">
               </a>
@@ -274,6 +271,9 @@ html(lang='en')
               <a href="https://www.monetta.pl/">
                 <img class="sponsor" src="https://images.opencollective.com/monetta/7d65ae6/logo.png" style="height: 100px">
               </a>
+              <a href="https://www.partitionwizard.com/">
+                <img class="sponsor" src="https://images.opencollective.com/minitool-solution-ltd/1519aa6/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 4433d6c0bb2dfd267b528bd8e84c4c49c48d3fb0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jan 2020 16:38:45 -0500
Subject: [PATCH 0319/2348] chore: release 5.8.4

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f67622ff009..52ae23d2080 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.8.4 / 2020-01-02
+==================
+ * fix(populate): ensure populate virtual gets set to empty array if `localField` is undefined in the database #8455
+ * fix(connection): wrap `mongoose.connect()` server selection timeouts in MongooseTimeoutError for more readable stack traces #8451
+ * fix(populate): allow deselecting `foreignField` from projection by prefixing with `-` #8460
+ * fix(populate): support embedded discriminators with `refPath` when not all discriminator schemas have `refPath` #8452
+ * fix(array): allow defining `enum` on array if an array of numbers #8449
+
 5.8.3 / 2019-12-23
 ==================
  * fix: upgrade mongodb -> 3.4.1 #8430 [jaschaio](https://github.com/jaschaio)
diff --git a/package.json b/package.json
index 968c0ae5ae5..ab9391e6cdf 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.4-pre",
+  "version": "5.8.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b98849744516981f2225f11ece5a9f080c5776f7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 13:51:10 -0500
Subject: [PATCH 0320/2348] test(model): repro #8471

---
 test/model.discriminator.querying.test.js | 66 ++++++++++++++++++++++-
 1 file changed, 64 insertions(+), 2 deletions(-)

diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 61db4e8344a..df4e1ebc187 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -6,12 +6,14 @@
 
 const start = require('./common');
 
-const mongoose = start.mongoose;
-const Schema = mongoose.Schema;
 const assert = require('assert');
+const co = require('co');
 const random = require('../lib/utils').random;
 const util = require('util');
 
+const mongoose = start.mongoose;
+const Schema = mongoose.Schema;
+
 /**
  * Setup
  */
@@ -854,6 +856,66 @@ describe('model', function() {
       });
     });
 
+    describe('deleteOne and deleteMany (gh-8471)', function() {
+      it('adds discriminator filter if no conditions passed', () => {
+        const PeopleSchema = Schema({ job: String, name: String },
+          { discriminatorKey: 'job' });
+        
+        const People = db.model('gh8471_People', PeopleSchema);
+        
+        const DesignerSchema = Schema({ badge: String });
+        const Designer = People.discriminator('gh8471_Designer', DesignerSchema, 'Designer');
+        
+        const DeveloperSchema = Schema({ coffeeAmount: Number });
+        const Developer = People.discriminator('gh8471_Developer', DeveloperSchema, 'Developer');
+
+        return co(function*() {
+          yield Designer.create({
+            name: 'John',
+            job: 'Designer',
+            badge: 'green'
+          });
+
+          let numDesigners = yield Designer.countDocuments();
+          let numDevelopers = yield Developer.countDocuments();
+          let total = yield People.countDocuments();
+          assert.equal(numDesigners, 1);
+          assert.equal(numDevelopers, 0);
+          assert.equal(total, 1);
+
+          yield Developer.deleteOne();
+
+          numDesigners = yield Designer.countDocuments();
+          numDevelopers = yield Developer.countDocuments();
+          total = yield People.countDocuments();
+          assert.equal(numDesigners, 1);
+          assert.equal(numDevelopers, 0);
+          assert.equal(total, 1);
+
+          yield Developer.create([
+            { name: 'Mike', job: 'Developer', coffeeAmount: 25 },
+            { name: 'Joe', job: 'Developer', coffeeAmount: 14 }
+          ]);
+
+          numDesigners = yield Designer.countDocuments();
+          numDevelopers = yield Developer.countDocuments();
+          total = yield People.countDocuments();
+          assert.equal(numDesigners, 1);
+          assert.equal(numDevelopers, 2);
+          assert.equal(total, 3);
+
+          yield Developer.deleteMany();
+
+          numDesigners = yield Designer.countDocuments();
+          numDevelopers = yield Developer.countDocuments();
+          total = yield People.countDocuments();
+          assert.equal(numDesigners, 1);
+          assert.equal(numDevelopers, 0);
+          assert.equal(total, 1);
+        });
+      });
+    });
+
     describe('aggregate', function() {
       let impressionEvent, conversionEvent, ignoredImpressionEvent;
 

From 5c33b4c1c7d0eb49251c457dcf16e4b396fe68c8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 13:51:35 -0500
Subject: [PATCH 0321/2348] fix(model): ensure deleteOne() and deleteMany() set
 discriminator filter even if no conditions passed

Fix #8471
---
 lib/model.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 5593b76f11a..e5f51affd34 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1934,12 +1934,12 @@ Model.deleteOne = function deleteOne(conditions, options, callback) {
     options = null;
   }
 
-  const mq = new this.Query(conditions, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.collection);
   mq.setOptions(options);
 
   callback = this.$handleCallbackError(callback);
 
-  return mq.deleteOne(callback);
+  return mq.deleteOne(conditions, callback);
 };
 
 /**
@@ -1974,12 +1974,12 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
     options = null;
   }
 
-  const mq = new this.Query(conditions, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.collection);
   mq.setOptions(options);
 
   callback = this.$handleCallbackError(callback);
 
-  return mq.deleteMany(callback);
+  return mq.deleteMany(conditions, callback);
 };
 
 /**

From 622fb4fc6379dc75abeb96ea038817a33b40d725 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 13:52:24 -0500
Subject: [PATCH 0322/2348] chore: now working on 5.8.5

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index ab9391e6cdf..3c92a0c22e0 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.4",
+  "version": "5.8.5-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 3404a2befe10ef892f3b9a1bb52b2ecf3f3ccf77 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 14:04:17 -0500
Subject: [PATCH 0323/2348] style: fix lint

---
 test/model.discriminator.querying.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index df4e1ebc187..ed80ad596dc 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -860,12 +860,12 @@ describe('model', function() {
       it('adds discriminator filter if no conditions passed', () => {
         const PeopleSchema = Schema({ job: String, name: String },
           { discriminatorKey: 'job' });
-        
+
         const People = db.model('gh8471_People', PeopleSchema);
-        
+
         const DesignerSchema = Schema({ badge: String });
         const Designer = People.discriminator('gh8471_Designer', DesignerSchema, 'Designer');
-        
+
         const DeveloperSchema = Schema({ coffeeAmount: Number });
         const Developer = People.discriminator('gh8471_Developer', DeveloperSchema, 'Developer');
 

From 1c6f1246f687152262a48a309fa86dc9797439a4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 14:54:12 -0500
Subject: [PATCH 0324/2348] test(update): repro #8467

---
 test/model.update.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 8399a8b9cbf..74cd026d7d0 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3382,6 +3382,22 @@ describe('model: updateOne: ', function() {
     });
   });
 
+  it('moves $set of immutable properties to $setOnInsert (gh-8467)', function() {
+    const Model = db.model('gh8467', Schema({
+      name: String,
+      age: { type: Number, default: 25, immutable: true }
+    }));
+
+    const _opts = { upsert: true, setDefaultsOnInsert: true };
+
+    return co(function*() {
+      yield Model.findOneAndUpdate({ name: 'John' }, { name: 'John', age: 20 }, _opts);
+
+      const doc = yield Model.findOne().lean();
+      assert.equal(doc.age, 20);
+    });
+  });
+
   describe('mongodb 42 features', function() {
     before(function(done) {
       start.mongodVersion((err, version) => {

From a7c72e6fc8d4a190a63dd87ca760b6b710922015 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 14:54:29 -0500
Subject: [PATCH 0325/2348] fix(update): move top level $set of immutable
 properties to $setOnInsert so upserting with immutable properties actually
 sets the property

Fix #8467
---
 lib/helpers/query/castUpdate.js               |  3 ++
 lib/helpers/query/handleImmutable.js          |  1 +
 lib/helpers/update/moveImmutableProperties.js | 53 +++++++++++++++++++
 test/model.update.test.js                     |  2 +-
 4 files changed, 58 insertions(+), 1 deletion(-)
 create mode 100644 lib/helpers/update/moveImmutableProperties.js

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 0b556056c16..01114523512 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -8,6 +8,7 @@ const castNumber = require('../../cast/number');
 const cast = require('../../cast');
 const getEmbeddedDiscriminatorPath = require('./getEmbeddedDiscriminatorPath');
 const handleImmutable = require('./handleImmutable');
+const moveImmutableProperties = require('../update/moveImmutableProperties');
 const schemaMixedSymbol = require('../../schema/symbols').schemaMixedSymbol;
 const utils = require('../../utils');
 
@@ -51,6 +52,8 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
 
   filter = filter || {};
 
+  moveImmutableProperties(schema, obj, context);
+
   while (i--) {
     const op = ops[i];
     // if overwrite is set, don't do any of the special $set stuff
diff --git a/lib/helpers/query/handleImmutable.js b/lib/helpers/query/handleImmutable.js
index 2b460611cbb..22adb3c50de 100644
--- a/lib/helpers/query/handleImmutable.js
+++ b/lib/helpers/query/handleImmutable.js
@@ -22,6 +22,7 @@ module.exports = function handleImmutable(schematype, strict, obj, key, fullPath
     throw new StrictModeError(null,
       `Field ${fullPath} is immutable and strict = 'throw'`);
   }
+
   delete obj[key];
   return true;
 };
diff --git a/lib/helpers/update/moveImmutableProperties.js b/lib/helpers/update/moveImmutableProperties.js
new file mode 100644
index 00000000000..d69e719ca13
--- /dev/null
+++ b/lib/helpers/update/moveImmutableProperties.js
@@ -0,0 +1,53 @@
+'use strict';
+
+const get = require('../get');
+
+/**
+ * Given an update, move all $set on immutable properties to $setOnInsert.
+ * No need to check for upserts, because there's no harm in setting
+ * $setOnInsert even if `upsert` is false.
+ */
+
+module.exports = function moveImmutableProperties(schema, update, ctx) {
+  if (update == null) {
+    return;
+  }
+
+  const keys = Object.keys(update);
+  for (const key of keys) {
+    const isDollarKey = key.startsWith('$');
+
+    if (key === '$set') {
+      const updatedPaths = Object.keys(update[key]);
+      for (const path of updatedPaths) {
+        _walkUpdatePath(schema, update[key], path, update, ctx);
+      }
+    } else if (!isDollarKey) {
+      _walkUpdatePath(schema, update, key, update, ctx);
+    }
+
+  }
+};
+
+function _walkUpdatePath(schema, op, path, update, ctx) {
+  const schematype = schema.path(path);
+  if (schematype == null) {
+    return;
+  }
+
+  let immutable = get(schematype, 'options.immutable', null);
+  if (immutable == null) {
+    return;
+  }
+  if (typeof immutable === 'function') {
+    immutable = immutable.call(ctx, ctx);
+  }
+
+  if (!immutable) {
+    return;
+  }
+
+  update.$setOnInsert = update.$setOnInsert || {};
+  update.$setOnInsert[path] = op[path];
+  delete op[path];
+}
\ No newline at end of file
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 74cd026d7d0..7c915227943 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3391,7 +3391,7 @@ describe('model: updateOne: ', function() {
     const _opts = { upsert: true, setDefaultsOnInsert: true };
 
     return co(function*() {
-      yield Model.findOneAndUpdate({ name: 'John' }, { name: 'John', age: 20 }, _opts);
+      yield Model.updateOne({ name: 'John' }, { name: 'John', age: 20 }, _opts);
 
       const doc = yield Model.findOne().lean();
       assert.equal(doc.age, 20);

From f2cd74ee7d7b5a0af4bddce7f3299c3290a8dca6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 15:48:57 -0500
Subject: [PATCH 0326/2348] test(document): repro #8466

---
 test/document.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index a87e805b6b2..807e6986f06 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8415,4 +8415,29 @@ describe('document', function() {
       assert.ok(a.rel[1] instanceof mongoose.Types.ObjectId);
     });
   });
+
+  it('handles errors with name set to "ValidationError" (gh-8466)', () => {
+    const childSchema = Schema({ name: String });
+
+    childSchema.pre('validate', function() {
+      if (this.name === 'Invalid') {
+        const error = new Error('invalid name');
+        error.name = 'ValidationError';
+        throw error;
+      }
+    });
+
+    const fatherSchema = Schema({ children: [childSchema] });
+    const Father = db.model('gh8466', fatherSchema);
+
+    const doc = new Father({
+      children: [{ name: 'Valid' }, { name: 'Invalid' }]
+    });
+
+    return doc.validate().then(() => assert.ok(false), err => {
+      assert.ok(err);
+      assert.ok(err.errors['children']);
+      assert.equal(err.errors['children'].message, 'invalid name');
+    });
+  });
 });

From 0825be44b5301fe8fa4adee004523358dbe88725 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 15:49:10 -0500
Subject: [PATCH 0327/2348] fix(document): allow pre('validate') hooks to throw
 errors with `name = 'ValidationError'`

Fix #8466
---
 lib/document.js             | 8 ++++----
 lib/schema/documentarray.js | 3 ++-
 lib/types/embedded.js       | 3 ++-
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 3e09e6f0453..7028b44838f 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -12,7 +12,8 @@ const ObjectExpectedError = require('./error/objectExpected');
 const ObjectParameterError = require('./error/objectParameter');
 const Schema = require('./schema');
 const StrictModeError = require('./error/strict');
-const ValidatorError = require('./schematype').ValidatorError;
+const ValidationError = require('./error/validation');
+const ValidatorError = require('./error/validator');
 const VirtualType = require('./virtualtype');
 const cleanModifiedSubpaths = require('./helpers/document/cleanModifiedSubpaths');
 const compile = require('./helpers/document/compile').compile;
@@ -28,7 +29,6 @@ const internalToObjectOptions = require('./options').internalToObjectOptions;
 const mpath = require('mpath');
 const utils = require('./utils');
 
-const ValidationError = MongooseError.ValidationError;
 const clone = utils.clone;
 const deepEqual = utils.deepEqual;
 const isMongooseObject = utils.isMongooseObject;
@@ -2303,7 +2303,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       p.doValidate(val, function(err) {
         if (err && (!p.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
           if (p.$isSingleNested &&
-              err.name === 'ValidationError' &&
+              err instanceof ValidationError &&
               p.schema.options.storeSubdocValidationError === false) {
             return --total || complete();
           }
@@ -2400,7 +2400,7 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     });
     if (err && (!p.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
       if (p.$isSingleNested &&
-          err.name === 'ValidationError' &&
+          err instanceof ValidationError &&
           p.schema.options.storeSubdocValidationError === false) {
         return;
       }
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 49733ac9863..286c6247915 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -10,6 +10,7 @@ const EventEmitter = require('events').EventEmitter;
 const SchemaDocumentArrayOptions =
   require('../options/SchemaDocumentArrayOptions');
 const SchemaType = require('../schematype');
+const ValidationError = require('../error/validation');
 const discriminator = require('../helpers/model/discriminator');
 const get = require('../helpers/get');
 const handleIdOption = require('../helpers/schema/handleIdOption');
@@ -228,7 +229,7 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
     function callback(err) {
       if (err != null) {
         error = err;
-        if (error.name !== 'ValidationError') {
+        if (!(error instanceof ValidationError)) {
           error.$isArrayValidatorError = true;
         }
       }
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 2ea49355a4d..13d3f567dc3 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -8,6 +8,7 @@
 
 const Document = require('../document_provider')();
 const EventEmitter = require('events').EventEmitter;
+const ValidationError = require('../error/validation');
 const immediate = require('../helpers/immediate');
 const internalToObjectOptions = require('../options').internalToObjectOptions;
 const get = require('../helpers/get');
@@ -278,7 +279,7 @@ EmbeddedDocument.prototype.invalidate = function(path, err, val) {
   Document.prototype.invalidate.call(this, path, err, val);
 
   if (!this[documentArrayParent] || this.__index == null) {
-    if (err[validatorErrorSymbol] || err.name === 'ValidationError') {
+    if (err[validatorErrorSymbol] || err instanceof ValidationError) {
       return true;
     }
     throw err;

From be42fbdd1e99958f905e600875108985264f1e83 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 17:18:13 -0500
Subject: [PATCH 0328/2348] test(document): repro #8468

---
 test/document.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 807e6986f06..f4f189144ee 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8440,4 +8440,16 @@ describe('document', function() {
       assert.equal(err.errors['children'].message, 'invalid name');
     });
   });
+
+  it('throws an error if running validate() multiple times in parallel (gh-8468)', () => {
+    const Model = db.model('gh8468', Schema({ name: String }));
+
+    const doc = new Model({ name: 'test' });
+
+    doc.validate();
+
+    return doc.save().then(() => assert.ok(false), err => {
+      assert.equal(err.name, 'ParallelValidateError');
+    });
+  });
 });

From 9199bef82e0c2013dbc0676acbb9b7fddfaa4e8c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jan 2020 17:18:30 -0500
Subject: [PATCH 0329/2348] fix(document): throw error when running
 `validate()` multiple times on the same document

Fix #8468
---
 lib/document.js                   | 39 +++++++++++++++++++++----------
 lib/error/parallelSave.js         |  2 +-
 lib/error/parallelValidate.js     | 33 ++++++++++++++++++++++++++
 lib/plugins/validateBeforeSave.js |  2 +-
 4 files changed, 62 insertions(+), 14 deletions(-)
 create mode 100644 lib/error/parallelValidate.js

diff --git a/lib/document.js b/lib/document.js
index 7028b44838f..0987ae9dcd3 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -10,6 +10,7 @@ const MongooseError = require('./error/index');
 const MixedSchema = require('./schema/mixed');
 const ObjectExpectedError = require('./error/objectExpected');
 const ObjectParameterError = require('./error/objectParameter');
+const ParallelValidateError = require('./error/parallelValidate');
 const Schema = require('./schema');
 const StrictModeError = require('./error/strict');
 const ValidationError = require('./error/validation');
@@ -2026,6 +2027,14 @@ Document.prototype.isDirectSelected = function isDirectSelected(path) {
  */
 
 Document.prototype.validate = function(pathsToValidate, options, callback) {
+  let parallelValidate;
+
+  if (this.$__.validating) {
+    parallelValidate = new ParallelValidateError(this);
+  } else {
+    this.$__.validating = new ParallelValidateError(this);
+  }
+
   if (typeof pathsToValidate === 'function') {
     callback = pathsToValidate;
     options = null;
@@ -2037,7 +2046,12 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
   }
 
   return utils.promiseOrCallback(callback, cb => {
-    this.$__validate(pathsToValidate, options, function(error) {
+    if (parallelValidate != null) {
+      return cb(parallelValidate);
+    }
+
+    this.$__validate(pathsToValidate, options, (error) => {
+      this.$__.validating = null;
       cb(error);
     });
   }, this.constructor.events);
@@ -2198,34 +2212,35 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
 
   const _this = this;
   const _complete = () => {
-    let err = this.$__.validationError;
+    let validationError = this.$__.validationError;
     this.$__.validationError = undefined;
 
-    if (shouldValidateModifiedOnly && err != null) {
+    if (shouldValidateModifiedOnly && validationError != null) {
       // Remove any validation errors that aren't from modified paths
-      const errors = Object.keys(err.errors);
+      const errors = Object.keys(validationError.errors);
       for (const errPath of errors) {
         if (!this.isModified(errPath)) {
-          delete err.errors[errPath];
+          delete validationError.errors[errPath];
         }
       }
-      if (Object.keys(err.errors).length === 0) {
-        err = void 0;
+      if (Object.keys(validationError.errors).length === 0) {
+        validationError = void 0;
       }
     }
 
     this.$__.cachedRequired = {};
     this.emit('validate', _this);
     this.constructor.emit('validate', _this);
-    if (err) {
-      for (const key in err.errors) {
+    if (validationError) {
+      for (const key in validationError.errors) {
         // Make sure cast errors persist
-        if (!this[documentArrayParent] && err.errors[key] instanceof MongooseError.CastError) {
-          this.invalidate(key, err.errors[key]);
+        if (!this[documentArrayParent] &&
+            validationError.errors[key] instanceof MongooseError.CastError) {
+          this.invalidate(key, validationError.errors[key]);
         }
       }
 
-      return err;
+      return validationError;
     }
   };
 
diff --git a/lib/error/parallelSave.js b/lib/error/parallelSave.js
index c9a189caa0f..1b546135582 100644
--- a/lib/error/parallelSave.js
+++ b/lib/error/parallelSave.js
@@ -15,7 +15,7 @@ const MongooseError = require('./');
 
 function ParallelSaveError(doc) {
   const msg = 'Can\'t save() the same doc multiple times in parallel. Document: ';
-  MongooseError.call(this, msg + doc.id);
+  MongooseError.call(this, msg + doc._id);
   this.name = 'ParallelSaveError';
 }
 
diff --git a/lib/error/parallelValidate.js b/lib/error/parallelValidate.js
new file mode 100644
index 00000000000..c5cc83b89fa
--- /dev/null
+++ b/lib/error/parallelValidate.js
@@ -0,0 +1,33 @@
+'use strict';
+
+/*!
+ * Module dependencies.
+ */
+
+const MongooseError = require('./mongooseError');
+
+/**
+ * ParallelValidate Error constructor.
+ *
+ * @inherits MongooseError
+ * @api private
+ */
+
+function ParallelValidateError(doc) {
+  const msg = 'Can\'t validate() the same doc multiple times in parallel. Document: ';
+  MongooseError.call(this, msg + doc._id);
+  this.name = 'ParallelValidateError';
+}
+
+/*!
+ * Inherits from MongooseError.
+ */
+
+ParallelValidateError.prototype = Object.create(MongooseError.prototype);
+ParallelValidateError.prototype.constructor = MongooseError;
+
+/*!
+ * exports
+ */
+
+module.exports = ParallelValidateError;
\ No newline at end of file
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index 9efd7e0fa02..cb65577ffa8 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -6,7 +6,7 @@
 
 module.exports = function(schema) {
   const unshift = true;
-  schema.pre('save', false, function(next, options) {
+  schema.pre('save', false, function validateBeforeSave(next, options) {
     const _this = this;
     // Nested docs have their own presave
     if (this.ownerDocument) {

From c79a6b9c0ca314ca133e1b9d35ee53facb949755 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Jan 2020 10:41:09 -0500
Subject: [PATCH 0330/2348] fix(document): avoid double-running validators on
 single nested subdocs within single nested subdocs

Fix tests for #8468
---
 lib/document.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 0987ae9dcd3..0e7d033e46b 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2097,6 +2097,11 @@ function _getPathsToValidate(doc) {
   paths = paths.concat(Object.keys(doc.$__.activePaths.states.modify));
   paths = paths.concat(Object.keys(doc.$__.activePaths.states.default));
 
+  // Single nested paths (paths embedded under single nested subdocs) will
+  // be validated on their own when we call `validate()` on the subdoc itself.
+  // Re: gh-8468
+  paths = paths.filter(p => !doc.schema.singleNestedPaths.hasOwnProperty(p));
+
   if (!doc.ownerDocument) {
     const subdocs = doc.$__getAllSubdocs();
     let subdoc;

From 58c4c1af426b1a7e95eb736a5f227f5553189368 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Jan 2020 10:45:54 -0500
Subject: [PATCH 0331/2348] chore: update opencollective sponsor link

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 26c8369370c..60767b50353 100644
--- a/index.pug
+++ b/index.pug
@@ -271,7 +271,7 @@ html(lang='en')
               <a href="https://www.monetta.pl/">
                 <img class="sponsor" src="https://images.opencollective.com/monetta/7d65ae6/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.partitionwizard.com/">
+              <a href="https://www.minitool.com/">
                 <img class="sponsor" src="https://images.opencollective.com/minitool-solution-ltd/1519aa6/logo.png" style="height: 100px">
               </a>
             </div>

From 64382ae73388a8182a12507de3d6c44c2a1a4a13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Jan 2020 16:34:02 -0500
Subject: [PATCH 0332/2348] test(populate): repro #8476

---
 test/model.populate.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 60af45542b4..fac765caa01 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8094,6 +8094,31 @@ describe('model: populate:', function() {
     });
   });
 
+  it('count option ignores skip (gh-4469) (gh-8476)', function() {
+    const childSchema = new Schema({ parentId: mongoose.ObjectId });
+
+    const parentSchema = new Schema({ name: String });
+    parentSchema.virtual('childCount', {
+      ref: 'gh8476_Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      count: true,
+      options: { skip: 2 }
+    });
+
+    const Child = db.model('gh8476_Child', childSchema);
+    const Parent = db.model('gh8476_Parent', parentSchema);
+
+    return co(function*() {
+      const p = yield Parent.create({ name: 'test' });
+
+      yield Child.create([{ parentId: p._id }, { parentId: p._id }, {}]);
+
+      const doc = yield Parent.findOne().populate('childCount');
+      assert.equal(doc.childCount, 2);
+    });
+  });
+
   it('count with deeply nested (gh-7573)', function() {
     const s1 = new mongoose.Schema({});
 

From 3949575e1a067528286f428d553bd5d41b0d5923 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Jan 2020 16:34:16 -0500
Subject: [PATCH 0333/2348] fix(model): avoid applying skip when populating
 virtual with count

Fix #8476
---
 lib/model.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index e5f51affd34..f0b46984a6b 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4378,7 +4378,12 @@ function populate(model, docs, options, callback) {
 function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
   const subPopulate = utils.clone(mod.options.populate);
 
-  const query = mod.model.find(match, select, mod.options.options);
+  const queryOptions = Object.assign({}, mod.options.options);
+  if (mod.count) {
+    delete queryOptions.skip;
+  }
+
+  const query = mod.model.find(match, select, queryOptions);
   // If we're doing virtual populate and projection is inclusive and foreign
   // field is not selected, automatically select it because mongoose needs it.
   // If projection is exclusive and client explicitly unselected the foreign

From f01240eeb6177077432909cf36b4c2bc56b165a1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 09:45:07 -0500
Subject: [PATCH 0334/2348] test(populate): repro #8475

---
 test/model.populate.test.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index fac765caa01..568085ef7eb 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9057,4 +9057,37 @@ describe('model: populate:', function() {
       assert.strictEqual(doc.searchResult.specialId, 'secret');
     });
   });
+
+  it('supports top-level match option (gh-8475)', function() {
+    const childSchema = Schema({ parentId: 'ObjectId', deleted: Boolean });
+
+    const parentSchema = Schema({ name: String });
+    parentSchema.virtual('childCount', {
+      ref: 'gh8475_Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      count: true,
+      match: { deleted: { $ne: true } }
+    });
+
+    const Child = db.model('gh8475_Child', childSchema);
+    const Parent = db.model('gh8475_Parent', parentSchema);
+
+    return co(function*() {
+      const p = yield Parent.create({ name: 'test' });
+
+      yield Child.create([
+        { parentId: p._id },
+        { parentId: p._id, deleted: true },
+        { parentId: p._id, deleted: false }
+      ]);
+
+      let doc = yield Parent.findOne().populate('childCount');
+      assert.equal(doc.childCount, 2);
+
+      doc = yield Parent.findOne().
+        populate({ path: 'childCount', match: { deleted: true } });
+      assert.equal(doc.childCount, 1);
+    });
+  });
 });

From a7ab660d3e31731ce86beaa7e02737f0fb050eab Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 09:45:34 -0500
Subject: [PATCH 0335/2348] fix(populate): support top-level match option for
 virtual populate

Fix #8475
---
 lib/helpers/populate/getModelsMapForPopulate.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 07e44587d77..37491964f8e 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -180,6 +180,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
     let match = get(options, 'match', null) ||
       get(currentOptions, 'match', null) ||
+      get(options, 'virtual.options.match', null) ||
       get(options, 'virtual.options.options.match', null);
 
     const hasMatchFunction = typeof match === 'function';

From 6c6d74423263eec1442bb0777235cf3d64a1f28d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 10:16:07 -0500
Subject: [PATCH 0336/2348] refactor: use VirtualOptions class to make it
 easier to document options for populate virtuals

Re: #8475
---
 lib/options/VirtualOptions.js | 124 ++++++++++++++++++++++++++++++++++
 lib/schema.js                 |   7 +-
 2 files changed, 129 insertions(+), 2 deletions(-)
 create mode 100644 lib/options/VirtualOptions.js

diff --git a/lib/options/VirtualOptions.js b/lib/options/VirtualOptions.js
new file mode 100644
index 00000000000..0e755e9b163
--- /dev/null
+++ b/lib/options/VirtualOptions.js
@@ -0,0 +1,124 @@
+'use strict';
+
+const opts = require('./propertyOptions');
+
+class VirtualOptions {
+  constructor(obj) {
+    Object.assign(this, obj);
+
+    if (obj != null && obj.options != null) {
+      this.options = Object.assign({}, obj.options);
+    }
+  }
+}
+
+/**
+ * Marks this virtual as a populate virtual, and specifies the model to
+ * use for populate.
+ *
+ * @api public
+ * @property ref
+ * @memberOf VirtualOptions
+ * @type String|Model|Function
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'ref', opts);
+
+/**
+ * Marks this virtual as a populate virtual, and specifies the path that
+ * contains the name of the model to populate
+ *
+ * @api public
+ * @property refPath
+ * @memberOf VirtualOptions
+ * @type String|Function
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'refPath', opts);
+
+/**
+ * The name of the property in the local model to match to `foreignField`
+ * in the foreign model.
+ *
+ * @api public
+ * @property localField
+ * @memberOf VirtualOptions
+ * @type String|Function
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'localField', opts);
+
+/**
+ * The name of the property in the foreign model to match to `localField`
+ * in the local model.
+ *
+ * @api public
+ * @property foreignField
+ * @memberOf VirtualOptions
+ * @type String|Function
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'foreignField', opts);
+
+/**
+ * Whether to populate this virtual as a single document (true) or an
+ * array of documents (false).
+ *
+ * @api public
+ * @property justOne
+ * @memberOf VirtualOptions
+ * @type Boolean
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'justOne', opts);
+
+/**
+ * If true, populate just the number of documents where `localField`
+ * matches `foreignField`, as opposed to the documents themselves.
+ *
+ * If `count` is set, it overrides `justOne`.
+ *
+ * @api public
+ * @property count
+ * @memberOf VirtualOptions
+ * @type Boolean
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'count', opts);
+
+/**
+ * Add an additional filter to populate, in addition to `localField`
+ * matches `foreignField`.
+ *
+ * @api public
+ * @property match
+ * @memberOf VirtualOptions
+ * @type Object|Function
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'match', opts);
+
+/**
+ * Additional options to pass to the query used to `populate()`:
+ *
+ * - `sort`
+ * - `skip`
+ * - `limit`
+ *
+ * @api public
+ * @property options
+ * @memberOf VirtualOptions
+ * @type Object
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'options', opts);
+
+module.exports = VirtualOptions;
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index 9750f8532fd..82d557659c5 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -9,6 +9,7 @@ const Kareem = require('kareem');
 const MongooseError = require('./error/mongooseError');
 const SchemaType = require('./schematype');
 const SchemaTypeOptions = require('./options/SchemaTypeOptions');
+const VirtualOptions = require('./options/VirtualOptions');
 const VirtualType = require('./virtualtype');
 const addAutoId = require('./helpers/schema/addAutoId');
 const applyTimestampsToChildren = require('./helpers/update/applyTimestampsToChildren');
@@ -1714,12 +1715,14 @@ Schema.prototype.virtual = function(name, options) {
     return this.virtual(name.path, name.options);
   }
 
+  options = new VirtualOptions(options);
+
   if (utils.hasUserDefinedProperty(options, ['ref', 'refPath'])) {
-    if (!options.localField) {
+    if (options.localField == null) {
       throw new Error('Reference virtuals require `localField` option');
     }
 
-    if (!options.foreignField) {
+    if (options.foreignField == null) {
       throw new Error('Reference virtuals require `foreignField` option');
     }
 

From e8d375622f1154c901dfe10e07dda0c4830fb5d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 11:20:03 -0500
Subject: [PATCH 0337/2348] refactor: reuse model collections where possible
 for populate tests re: #8481

---
 test/common.js              |   5 +-
 test/model.populate.test.js | 543 +++++++++++++++++++-----------------
 2 files changed, 285 insertions(+), 263 deletions(-)

diff --git a/test/common.js b/test/common.js
index 21cbb8ab3f3..c4252b7946f 100644
--- a/test/common.js
+++ b/test/common.js
@@ -186,8 +186,11 @@ before(function(done) {
   dropDBs(done);
 });
 
-after(function() {
+after(function(done) {
   dropDBs(() => {});
+
+  // Give `dropDatabase()` some time to run
+  setTimeout(() => done(), 250);
 });
 
 module.exports.server = server = new Server('mongod', {
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 568085ef7eb..bd71e1649ee 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -17,6 +17,8 @@ const Schema = mongoose.Schema;
 const ObjectId = Schema.ObjectId;
 const DocObjectId = mongoose.Types.ObjectId;
 
+const collectionName = 'model.populate';
+
 /**
  * Tests.
  */
@@ -75,6 +77,21 @@ describe('model: populate:', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => {
+    const arr = [];
+
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
   it('populating array of object', function(done) {
     const BlogPost = db.model('RefBlogPost', posts);
     const User = db.model('RefUser', users);
@@ -1887,7 +1904,7 @@ describe('model: populate:', function() {
   });
 
   it('refs should cast to ObjectId from hexstrings', function(done) {
-    const BP = mongoose.model('RefBlogPost');
+    const BP = db.model('RefBlogPost', posts);
     const bp = new BP;
     bp._creator = new DocObjectId().toString();
     assert.ok(bp._creator instanceof DocObjectId);
@@ -2047,6 +2064,7 @@ describe('model: populate:', function() {
 
     const M1 = db.model('_idAndid', S1);
     const M2 = db.model('populateWorksWith_idAndidSchemas', S2);
+    db.model('StringRefRequired', Schema({_id: String, val: String}), random());
 
     M1.create(
       {id: 'The Tiger That Isn\'t'}
@@ -3249,8 +3267,8 @@ describe('model: populate:', function() {
         }]
       });
 
-      const Post = db.model('gh6913_Post', PostSchema);
-      const User = db.model('gh6913_User', UserSchema);
+      const Post = db.model('Post', PostSchema);
+      const User = db.model('User', UserSchema);
 
       const user = {
         _id: mongoose.Types.ObjectId(),
@@ -3264,7 +3282,7 @@ describe('model: populate:', function() {
           {
             references: [{
               item: user._id,
-              kind: 'gh6913_User'
+              kind: 'User'
             }]
           }
         ]
@@ -5105,12 +5123,12 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('authors', {
-          ref: 'gh7795_Author',
+          ref: 'Author',
           localField: '_id',
           foreignField: 'authored'
         });
 
-        const BlogPost = db.model('gh7795_BlogPost', BlogPostSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         return co(function*() {
           yield BlogPost.create({ _id: 1, title: 'test' });
@@ -5463,7 +5481,7 @@ describe('model: populate:', function() {
           title: String,
           author: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh6115_Author'
+            ref: 'Author'
           }
         });
         const authorSchema = new Schema({
@@ -5471,7 +5489,7 @@ describe('model: populate:', function() {
         });
 
         const Article = db.model('gh6115_Article', articleSchema);
-        const Author = db.model('gh6115_Author', authorSchema);
+        const Author = db.model('Author', authorSchema);
 
         const author = new Author({ name: 'Val' });
         const article = new Article({
@@ -6470,7 +6488,7 @@ describe('model: populate:', function() {
         const dateActivitySchema = new Schema({
           postedBy: {
             type: Schema.Types.ObjectId,
-            ref: 'gh5858_User',
+            ref: 'User',
             required: true
           }
         }, options);
@@ -6487,7 +6505,7 @@ describe('model: populate:', function() {
           kind: String
         }, options);
 
-        const User = db.model('gh5858_User', { name: String });
+        const User = db.model('User', { name: String });
         const Activity = db.model('gh5858_0', activitySchema);
         const DateActivity = Activity.discriminator('gh5858_1', dateActivitySchema);
         const EventActivity = Activity.discriminator('gh5858_2', eventActivitySchema);
@@ -6846,7 +6864,7 @@ describe('model: populate:', function() {
           content: String,
           user: {
             type: Schema.Types.ObjectId,
-            ref: 'gh6528_User'
+            ref: 'User'
           }
         });
 
@@ -6863,16 +6881,16 @@ describe('model: populate:', function() {
         }, { timestamps: true });
 
         postSchema.virtual('comments', {
-          ref: 'gh6528_Comment',
+          ref: 'Comment',
           localField: 'commentIds',
           foreignField: '_id',
           justOne: false
         });
 
-        const User = db.model('gh6528_User', userSchema);
+        const User = db.model('User', userSchema);
         const Teacher = db.model('gh6528_Teacher', teachSchema);
-        const Post = db.model('gh6528_Post', postSchema);
-        const Comment = db.model('gh6528_Comment', commentSchema);
+        const Post = db.model('Post', postSchema);
+        const Comment = db.model('Comment', commentSchema);
 
         const users = [];
         const teachers = [];
@@ -7078,7 +7096,7 @@ describe('model: populate:', function() {
       it('handles virtual embedded discriminator underneath single nested (gh-6571)', co.wrap(function*() {
         // Generate Users Model
         const userSchema = new Schema({ id: Number, name: String });
-        const User = db.model('gh6571_Users', userSchema);
+        const User = db.model('User', userSchema);
 
         // Generate Product Model
         const productSchema = new Schema({ id: Number, name: String });
@@ -7100,12 +7118,12 @@ describe('model: populate:', function() {
         const flexibleUserSchema = new Schema({ users: [{}] });
 
         flexibleUserSchema.virtual('users_$', {
-          ref: 'gh6571_Users',
+          ref: 'User',
           localField: 'users.id',
           foreignField: 'id'
         });
 
-        docArray.discriminator('6571_UserDisc', flexibleUserSchema);
+        docArray.discriminator('UserDisc', flexibleUserSchema);
 
         const flexibleProductSchema = new Schema({ products: [{}] });
 
@@ -7126,7 +7144,7 @@ describe('model: populate:', function() {
           outer: {
             inner: {
               flexible: [
-                { kind: '6571_UserDisc', users: [{ id: 111, refKey: 'Users' }] },
+                { kind: 'UserDisc', users: [{ id: 111, refKey: 'Users' }] },
                 { kind: '6571_ProductDisc', products: [{ id: 222, refKey: 'Products' }] }
               ]
             }
@@ -7266,7 +7284,7 @@ describe('model: populate:', function() {
   describe('lean + deep populate (gh-6498)', function() {
     const isLean = v => v != null && !(v instanceof mongoose.Document);
 
-    before(function() {
+    beforeEach(function() {
       const userSchema = new Schema({
         name: String,
         roomId: { type: Schema.ObjectId, ref: 'gh6498_Room' }
@@ -7276,7 +7294,7 @@ describe('model: populate:', function() {
         officeId: { type: Schema.ObjectId, ref: 'gh6498_Office' }
       });
 
-      const User = db.model('gh6498_User', userSchema);
+      const User = db.model('User', userSchema);
       const Office = db.model('gh6498_Office', officeSchema);
       const Room = db.model('gh6498_Room', roomSchema);
 
@@ -7292,7 +7310,7 @@ describe('model: populate:', function() {
 
     it('document, and subdocuments are not lean by default', function() {
       return co(function*() {
-        const user = yield db.model('gh6498_User').findOne().populate({
+        const user = yield db.model('User').findOne().populate({
           path: 'roomId',
           populate: {
             path: 'officeId'
@@ -7307,7 +7325,7 @@ describe('model: populate:', function() {
 
     it('.lean() makes query result, and all populated fields lean', function() {
       return co(function*() {
-        const user = yield db.model('gh6498_User').findOne().
+        const user = yield db.model('User').findOne().
           populate({
             path: 'roomId',
             populate: {
@@ -7324,7 +7342,7 @@ describe('model: populate:', function() {
 
     it('disabling lean at some populating level reflects on it, and descendants', function() {
       return co(function*() {
-        const user = yield db.model('gh6498_User').findOne().
+        const user = yield db.model('User').findOne().
           populate({
             path: 'roomId',
             options: { lean: false },
@@ -7342,7 +7360,7 @@ describe('model: populate:', function() {
 
     it('enabling lean at some populating level reflects on it, and descendants', function() {
       return co(function*() {
-        const user = yield db.model('gh6498_User').findOne().populate({
+        const user = yield db.model('User').findOne().populate({
           path: 'roomId',
           options: { lean: true },
           populate: {
@@ -7358,7 +7376,7 @@ describe('model: populate:', function() {
 
     it('disabling lean on nested population overwrites parent lean', function() {
       return co(function*() {
-        const user = yield db.model('gh6498_User').findOne().populate({
+        const user = yield db.model('User').findOne().populate({
           path: 'roomId',
           options: { lean: true },
           populate: {
@@ -7372,229 +7390,230 @@ describe('model: populate:', function() {
         assert.equal(isLean(user.roomId.officeId), false);
       });
     });
-    it('populates virtual of embedded discriminator with dynamic ref (gh-6554)', function() {
-      const userSchema = new Schema({
-        employeeId: Number,
-        name: String
-      });
+  });
 
-      const UserModel = db.model('gh6554_Users', userSchema, 'users');
+  it('populates virtual of embedded discriminator with dynamic ref (gh-6554)', function() {
+    const userSchema = new Schema({
+      employeeId: Number,
+      name: String
+    });
 
-      const eventSchema = new Schema({
-        message: String
-      },{ discriminatorKey: 'kind' });
+    const UserModel = db.model('User', userSchema, 'users');
 
-      const batchSchema = new Schema({
-        events: [eventSchema]
-      });
+    const eventSchema = new Schema({
+      message: String
+    },{ discriminatorKey: 'kind' });
+
+    const batchSchema = new Schema({
+      events: [eventSchema]
+    });
 
-      const docArray = batchSchema.path('events');
+    const docArray = batchSchema.path('events');
 
-      const clickedSchema = new Schema({
-        element: { type: String },
-        users: [{}]
+    const clickedSchema = new Schema({
+      element: { type: String },
+      users: [{}]
+    },
+    {
+      toJSON: { virtuals: true },
+      toObject: { virtuals: true }
+    });
+
+    clickedSchema.virtual('users_$', {
+      ref: function(doc) {
+        return doc.events[0].users[0].refKey;
       },
-      {
-        toJSON: { virtuals: true },
-        toObject: { virtuals: true }
-      });
+      localField: 'users.ID',
+      foreignField: 'employeeId'
+    });
 
-      clickedSchema.virtual('users_$', {
-        ref: function(doc) {
-          return doc.events[0].users[0].refKey;
-        },
-        localField: 'users.ID',
-        foreignField: 'employeeId'
-      });
+    docArray.discriminator('Clicked', clickedSchema);
+    const Batch = db.model('gh6554_EventBatch', batchSchema);
 
-      docArray.discriminator('Clicked', clickedSchema);
-      const Batch = db.model('gh6554_EventBatch', batchSchema);
+    const user = { employeeId: 1, name: 'Test name' };
+    const batch = {
+      events: [
+        {
+          kind: 'Clicked',
+          element: '#hero',
+          message: 'hello',
+          users: [{ ID: 1, refKey: 'User' }]
+        }
+      ]
+    };
 
-      const user = { employeeId: 1, name: 'Test name' };
-      const batch = {
-        events: [
-          {
-            kind: 'Clicked',
-            element: '#hero',
-            message: 'hello',
-            users: [{ ID: 1, refKey: 'gh6554_Users' }]
-          }
-        ]
-      };
+    return co(function*() {
+      yield UserModel.create(user);
+      yield Batch.create(batch);
+      const doc = yield Batch.findOne({}).populate('events.users_$');
+      assert.strictEqual(doc.events[0].users_$[0].name, 'Test name');
+    });
+  });
 
-      return co(function*() {
-        yield UserModel.create(user);
-        yield Batch.create(batch);
-        const doc = yield Batch.findOne({}).populate('events.users_$');
-        assert.strictEqual(doc.events[0].users_$[0].name, 'Test name');
-      });
+  it('populates virtual of embedded discriminator with dynamic ref when more than one model name is returned (gh-6612)', function() {
+    const userSchema = new Schema({
+      employeeId: Number,
+      name: String
     });
 
-    it('populates virtual of embedded discriminator with dynamic ref when more than one model name is returned (gh-6612)', function() {
-      const userSchema = new Schema({
-        employeeId: Number,
-        name: String
-      });
+    const UserModel = db.model('User', userSchema);
 
-      const UserModel = db.model('gh6612_Users', userSchema);
+    const authorSchema = new Schema({
+      employeeId: Number,
+      name: String
+    });
 
-      const authorSchema = new Schema({
-        employeeId: Number,
-        name: String
-      });
+    const AuthorModel = db.model('Author', authorSchema);
 
-      const AuthorModel = db.model('gh6612_Author', authorSchema);
+    const eventSchema = new Schema({
+      message: String
+    }, { discriminatorKey: 'kind' });
 
-      const eventSchema = new Schema({
-        message: String
-      }, { discriminatorKey: 'kind' });
+    const batchSchema = new Schema({
+      events: [eventSchema]
+    });
 
-      const batchSchema = new Schema({
-        events: [eventSchema]
-      });
+    const docArray = batchSchema.path('events');
 
-      const docArray = batchSchema.path('events');
+    const clickedSchema = new Schema({
+      element: { type: String },
+      users: [{}]
+    },
+    {
+      toJSON: { virtuals: true },
+      toObject: { virtuals: true }
+    });
 
-      const clickedSchema = new Schema({
-        element: { type: String },
-        users: [{}]
+    clickedSchema.virtual('users_$', {
+      ref: function(doc) {
+        const refKeys = doc.events[0].users.map(user => user.refKey);
+        return refKeys;
       },
-      {
-        toJSON: { virtuals: true },
-        toObject: { virtuals: true }
-      });
-
-      clickedSchema.virtual('users_$', {
-        ref: function(doc) {
-          const refKeys = doc.events[0].users.map(user => user.refKey);
-          return refKeys;
-        },
-        localField: 'users.ID',
-        foreignField: 'employeeId'
-      });
+      localField: 'users.ID',
+      foreignField: 'employeeId'
+    });
 
-      docArray.discriminator('Clicked', clickedSchema);
-      const Batch = db.model('gh6612_EventBatch', batchSchema);
+    docArray.discriminator('Clicked', clickedSchema);
+    const Batch = db.model('gh6612_EventBatch', batchSchema);
 
-      const user = { employeeId: 1, name: 'Test name' };
-      const author = { employeeId: 2, name: 'Author Name' };
-      const batch = {
-        events: [
-          {
-            kind: 'Clicked',
-            element: '#hero',
-            message: 'hello',
-            users: [
-              { ID: 1, refKey: 'gh6612_Users' },
-              { ID: 2, refKey: 'gh6612_Author' }
-            ]
-          }
-        ]
-      };
+    const user = { employeeId: 1, name: 'Test name' };
+    const author = { employeeId: 2, name: 'Author Name' };
+    const batch = {
+      events: [
+        {
+          kind: 'Clicked',
+          element: '#hero',
+          message: 'hello',
+          users: [
+            { ID: 1, refKey: 'User' },
+            { ID: 2, refKey: 'Author' }
+          ]
+        }
+      ]
+    };
 
-      return co(function*() {
-        yield UserModel.create(user);
-        yield AuthorModel.create(author);
-        yield Batch.create(batch);
-        const doc = yield Batch.findOne({}).populate('events.users_$');
-        assert.strictEqual(doc.events[0].users_$[0].name, 'Test name');
-        assert.strictEqual(doc.events[0].users_$[1].name, 'Author Name');
-      });
+    return co(function*() {
+      yield UserModel.create(user);
+      yield AuthorModel.create(author);
+      yield Batch.create(batch);
+      const doc = yield Batch.findOne({}).populate('events.users_$');
+      assert.strictEqual(doc.events[0].users_$[0].name, 'Test name');
+      assert.strictEqual(doc.events[0].users_$[1].name, 'Author Name');
     });
+  });
 
-    it('uses getter if one is defined on the localField (gh-6618)', function() {
-      const userSchema = new Schema({
-        name: String
-      });
+  it('uses getter if one is defined on the localField (gh-6618)', function() {
+    const userSchema = new Schema({
+      name: String
+    });
 
-      const schema = new Schema({
-        referrer: {
-          type: String,
-          get: function(val) {
-            return val.slice(6);
-          }
+    const schema = new Schema({
+      referrer: {
+        type: String,
+        get: function(val) {
+          return val.slice(6);
         }
-      }, { toObject: { virtuals: true } });
+      }
+    }, { toObject: { virtuals: true } });
 
-      schema.virtual('referrerUser', {
-        ref: 'gh6618_user',
-        localField: 'referrer',
-        foreignField: 'name',
-        justOne: false,
-        getters: true
-      });
+    schema.virtual('referrerUser', {
+      ref: 'User',
+      localField: 'referrer',
+      foreignField: 'name',
+      justOne: false,
+      getters: true
+    });
 
-      const User = db.model('gh6618_user', userSchema);
-      const Test = db.model('gh6618_test', schema);
+    const User = db.model('User', userSchema);
+    const Test = db.model('gh6618_test', schema);
 
-      const user = new User({ name: 'billy' });
-      const test = new Test({ referrer: 'Model$' + user.name });
+    const user = new User({ name: 'billy' });
+    const test = new Test({ referrer: 'Model$' + user.name });
 
-      return co(function*() {
-        yield user.save();
-        yield test.save();
-        const pop = yield Test.findOne().populate('referrerUser');
-        assert.strictEqual(pop.referrerUser[0].name, 'billy');
+    return co(function*() {
+      yield user.save();
+      yield test.save();
+      const pop = yield Test.findOne().populate('referrerUser');
+      assert.strictEqual(pop.referrerUser[0].name, 'billy');
 
-        const pop2 = yield Test.findOne().populate({ path: 'referrerUser', options: { getters: false } });
-        assert.strictEqual(pop2.referrerUser.length, 0);
-      });
+      const pop2 = yield Test.findOne().populate({ path: 'referrerUser', options: { getters: false } });
+      assert.strictEqual(pop2.referrerUser.length, 0);
     });
+  });
 
-    it('populate child with same name as parent (gh-6839) (gh-6908)', function() {
-      const parentFieldsToPopulate = [
-        {path: 'children.child'},
-        {path: 'child'}
-      ];
+  it('populate child with same name as parent (gh-6839) (gh-6908)', function() {
+    const parentFieldsToPopulate = [
+      {path: 'children.child'},
+      {path: 'child'}
+    ];
 
-      const childSchema = new mongoose.Schema({ name: String });
-      const Child = db.model('gh6839_Child', childSchema);
+    const childSchema = new mongoose.Schema({ name: String });
+    const Child = db.model('Child', childSchema);
 
-      const parentSchema = new mongoose.Schema({
-        child: {type: mongoose.Schema.Types.ObjectId, ref: 'gh6839_Child'},
-        children: [{
-          child: {type: mongoose.Schema.Types.ObjectId, ref: 'gh6839_Child' }
-        }]
-      });
-      const Parent = db.model('gh6839_Parent', parentSchema);
+    const parentSchema = new mongoose.Schema({
+      child: {type: mongoose.Schema.Types.ObjectId, ref: 'Child'},
+      children: [{
+        child: {type: mongoose.Schema.Types.ObjectId, ref: 'Child' }
+      }]
+    });
+    const Parent = db.model('Parent', parentSchema);
 
-      return co(function*() {
-        let child = yield Child.create({ name: 'test' });
-        let p = yield Parent.create({ child: child });
+    return co(function*() {
+      let child = yield Child.create({ name: 'test' });
+      let p = yield Parent.create({ child: child });
 
-        child = yield Child.findById(child._id);
-        p = yield Parent.findById(p._id).populate(parentFieldsToPopulate);
-        p.children.push({ child: child });
-        yield p.save();
+      child = yield Child.findById(child._id);
+      p = yield Parent.findById(p._id).populate(parentFieldsToPopulate);
+      p.children.push({ child: child });
+      yield p.save();
 
-        p = yield p.populate(parentFieldsToPopulate).execPopulate();
-        assert.ok(p.children[0].child);
-        assert.equal(p.children[0].child.name, 'test');
-      });
+      p = yield p.populate(parentFieldsToPopulate).execPopulate();
+      assert.ok(p.children[0].child);
+      assert.equal(p.children[0].child.name, 'test');
     });
+  });
 
-    it('passes scope as Model instance (gh-6726)', function() {
-      const otherSchema = new Schema({ name: String });
-      const Other = db.model('gh6726_Other', otherSchema);
-      const schema = new Schema({
-        x: {
-          type: Schema.Types.ObjectId,
-          ref: 'gh6726_Other',
-          get: function(v) {
-            assert.strictEqual(this.constructor.name, 'model');
-            return v;
-          }
+  it('passes scope as Model instance (gh-6726)', function() {
+    const otherSchema = new Schema({ name: String });
+    const Other = db.model('gh6726_Other', otherSchema);
+    const schema = new Schema({
+      x: {
+        type: Schema.Types.ObjectId,
+        ref: 'gh6726_Other',
+        get: function(v) {
+          assert.strictEqual(this.constructor.name, 'model');
+          return v;
         }
-      });
-      const Test = db.model('gh6726_Test', schema);
-      const other = new Other({ name: 'Max' });
-      const test = new Test({ x: other._id });
-      return co(function*() {
-        yield other.save();
-        yield test.save();
-        const doc = yield Test.findOne({}).populate('x');
-        assert.strictEqual(doc.x.name, 'Max');
-      });
+      }
+    });
+    const Test = db.model('gh6726_Test', schema);
+    const other = new Other({ name: 'Max' });
+    const test = new Test({ x: other._id });
+    return co(function*() {
+      yield other.save();
+      yield test.save();
+      const doc = yield Test.findOne({}).populate('x');
+      assert.strictEqual(doc.x.name, 'Max');
     });
   });
 
@@ -7666,7 +7685,7 @@ describe('model: populate:', function() {
       text: String,
       author: {
         type: Schema.Types.ObjectId,
-        ref: 'gh6978_Author'
+        ref: 'Author'
       }
     });
 
@@ -7674,13 +7693,13 @@ describe('model: populate:', function() {
       content: String,
       comments: [{
         type: Schema.Types.ObjectId,
-        ref: 'gh6978_Comment'
+        ref: 'Comment'
       }]
     });
 
-    const Author = db.model('gh6978_Author', authorSchema);
-    const Comment = db.model('gh6978_Comment', commentSchema);
-    const Post = db.model('gh6978_Post', postSchema);
+    const Author = db.model('Author', authorSchema);
+    const Comment = db.model('Comment', commentSchema);
+    const Post = db.model('Post', postSchema);
 
     const authors = '123'.split('').map(n => {
       return new Author({ name: `author${n}`});
@@ -7768,7 +7787,7 @@ describe('model: populate:', function() {
     });
 
     postSchema.virtual('comments', {
-      ref: 'gh6988_Comment',
+      ref: 'Comment',
       localField: '_id',
       foreignField: 'postId'
     });
@@ -7777,8 +7796,8 @@ describe('model: populate:', function() {
       postId: { type: Schema.Types.ObjectId }
     });
 
-    const Post = db.model('gh6988_Post', postSchema);
-    const Comment = db.model('gh6988_Comment', commentSchema);
+    const Post = db.model('Post', postSchema);
+    const Comment = db.model('Comment', commentSchema);
 
     return co(function*() {
       const post = yield Post.create({ name: 'n1'});
@@ -7798,7 +7817,7 @@ describe('model: populate:', function() {
     });
 
     postSchema.virtual('comments', {
-      ref: 'gh8125_Comment',
+      ref: 'Comment',
       localField: '_id',
       foreignField: 'postId'
     });
@@ -7808,8 +7827,8 @@ describe('model: populate:', function() {
       text: String,
     });
 
-    const Post = db.model('gh8125_Post', postSchema);
-    const Comment = db.model('gh8125_Comment', commentSchema);
+    const Post = db.model('Post', postSchema);
+    const Comment = db.model('Comment', commentSchema);
 
     return co(function*() {
       const post = yield Post.create({ name: 'n1'});
@@ -7830,12 +7849,12 @@ describe('model: populate:', function() {
     });
 
     const schema = new Schema({
-      title: String,
+      name: String,
       data: Schema.Types.Mixed
     });
 
-    const Article = db.model('gh6985_Article', articleSchema);
-    const Test = db.model('gh6985_Test', schema);
+    const Article = db.model('Article', articleSchema);
+    const Test = db.model('User', schema);
 
     return co(function*() {
       const articles = yield Article.create([
@@ -7844,7 +7863,7 @@ describe('model: populate:', function() {
       ]);
 
       yield Test.create({
-        title: 'test',
+        name: 'Val',
         data: { articles: articles.map(a => a._id) }
       });
 
@@ -7852,7 +7871,7 @@ describe('model: populate:', function() {
       const popObj = {
         path: 'data.articles',
         select: 'title',
-        model: 'gh6985_Article',
+        model: 'Article',
         options: { lean: true }
       };
 
@@ -8026,7 +8045,7 @@ describe('model: populate:', function() {
 
   it('set model as ref in schema (gh-7253)', function() {
     const userSchema = new Schema({ name: String });
-    const User = db.model('gh7253_User', userSchema);
+    const User = db.model('User', userSchema);
 
     const postSchema = new Schema({
       user: {
@@ -8036,7 +8055,7 @@ describe('model: populate:', function() {
       user2: mongoose.ObjectId
     });
     postSchema.path('user2').ref(User);
-    const Post = db.model('gh7253_Post', postSchema);
+    const Post = db.model('Post', postSchema);
 
     return co(function*() {
       const user = yield User.create({ name: 'val' });
@@ -8054,21 +8073,21 @@ describe('model: populate:', function() {
 
     const parentSchema = new Schema({ name: String });
     parentSchema.virtual('childCount', {
-      ref: 'gh4469_Child',
+      ref: 'Child',
       localField: '_id',
       foreignField: 'parentId',
       count: true
     });
 
     parentSchema.virtual('children', {
-      ref: 'gh4469_Child',
+      ref: 'Child',
       localField: '_id',
       foreignField: 'parentId',
       count: false
     });
 
-    const Child = db.model('gh4469_Child', childSchema);
-    const Parent = db.model('gh4469_Parent', parentSchema);
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
       const p = yield Parent.create({ name: 'test' });
@@ -8099,15 +8118,15 @@ describe('model: populate:', function() {
 
     const parentSchema = new Schema({ name: String });
     parentSchema.virtual('childCount', {
-      ref: 'gh8476_Child',
+      ref: 'Child',
       localField: '_id',
       foreignField: 'parentId',
       count: true,
       options: { skip: 2 }
     });
 
-    const Child = db.model('gh8476_Child', childSchema);
-    const Parent = db.model('gh8476_Parent', parentSchema);
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
       const p = yield Parent.create({ name: 'test' });
@@ -8165,8 +8184,8 @@ describe('model: populate:', function() {
 
   it('explicit model option overrides refPath (gh-7273)', function() {
     const userSchema = new Schema({ name: String });
-    const User1 = db.model('gh7273_User_1', userSchema);
-    db.model('gh7273_User_2', userSchema);
+    const User1 = db.model('User', userSchema);
+    db.model('User2', userSchema);
 
     const postSchema = new Schema({
       user: {
@@ -8175,16 +8194,16 @@ describe('model: populate:', function() {
       },
       m: String
     });
-    const Post = db.model('gh7273_Post', postSchema);
+    const Post = db.model('Post', postSchema);
 
     return co(function*() {
       const user = yield User1.create({ name: 'val' });
-      yield Post.create({ user: user._id, m: 'gh7273_User_2' });
+      yield Post.create({ user: user._id, m: 'User2' });
 
       let post = yield Post.findOne().populate('user');
       assert.ok(!post.user);
 
-      post = yield Post.findOne().populate({ path: 'user', model: 'gh7273_User_1' });
+      post = yield Post.findOne().populate({ path: 'user', model: 'User' });
 
       assert.equal(post.user.name, 'val');
     });
@@ -8192,7 +8211,7 @@ describe('model: populate:', function() {
 
   it('clone option means identical ids get separate copies of doc (gh-3258)', function() {
     const userSchema = new Schema({ name: String });
-    const User = db.model('gh3258_User', userSchema);
+    const User = db.model('User', userSchema);
 
     const postSchema = new Schema({
       user: {
@@ -8202,7 +8221,7 @@ describe('model: populate:', function() {
       title: String
     });
 
-    const Post = db.model('gh3258_Post', postSchema);
+    const Post = db.model('Post', postSchema);
 
     return co(function*() {
       const user = yield User.create({ name: 'val' });
@@ -8423,12 +8442,12 @@ describe('model: populate:', function() {
   });
 
   it('can populate an array property whose name conflicts with array method (gh-7782)', function() {
-    const Child = db.model('gh7782_Child', Schema({ name: String }));
+    const Child = db.model('Child', Schema({ name: String }));
 
-    const Parent = db.model('gh7782_Parent', Schema({
+    const Parent = db.model('Parent', Schema({
       list: [{
         fill: {
-          child: { type:ObjectId, ref:'gh7782_Child' }
+          child: { type:ObjectId, ref:'Child' }
         }
       }]
     }));
@@ -8460,7 +8479,7 @@ describe('model: populate:', function() {
         }
       });
 
-      const User = db.model('gh6520_User', userSchema);
+      const User = db.model('User', userSchema);
       const Book = db2.model('Book', bookSchema);
       const Movie = db2.model('Movie', movieSchema);
 
@@ -8514,7 +8533,7 @@ describe('model: populate:', function() {
   });
 
   it('virtual refPath (gh-7848)', function() {
-    const Child = db.model('gh7848_Child', Schema({
+    const Child = db.model('Child', Schema({
       name: String,
       parentId: Number
     }));
@@ -8529,10 +8548,10 @@ describe('model: populate:', function() {
       foreignField: 'parentId',
       justOne: false
     });
-    const Parent = db.model('gh7848_Parent', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
-      yield Parent.create({ _id: 1, kind: 'gh7848_Child' });
+      yield Parent.create({ _id: 1, kind: 'Child' });
       yield Child.create({ name: 'test', parentId: 1 });
 
       const doc = yield Parent.findOne().populate('childDocs');
@@ -8543,7 +8562,7 @@ describe('model: populate:', function() {
 
   it('handles refPath on discriminator when populating top-level model (gh-5109)', function() {
     const options = { discriminatorKey: 'kind' };
-    const Post = db.model('gh5109_Post', new Schema({ time: Date, text: String }, options));
+    const Post = db.model('Post', new Schema({ time: Date, text: String }, options));
 
     const MediaPost = Post.discriminator('gh5109_MediaPost', new Schema({
       media: { type: Schema.Types.ObjectId, refPath: 'mediaType' },
@@ -8584,7 +8603,7 @@ describe('model: populate:', function() {
 
     postSchema.virtual('mediaType').get(function() { return this._mediaType; });
 
-    const Post = db.model('gh7341_Post', postSchema);
+    const Post = db.model('Post', postSchema);
     const Image = db.model('gh7341_Image', new Schema({ url: String }));
     const Video = db.model('gh7341_Video', new Schema({ url: String, duration: Number }));
 
@@ -8649,7 +8668,7 @@ describe('model: populate:', function() {
 
   it('handles virtual populate of an embedded discriminator nested path (gh-6488) (gh-8173)', function() {
     return co(function*() {
-      const UserModel = db.model('gh6488_User', Schema({
+      const UserModel = db.model('User', Schema({
         employeeId: Number,
         name: String
       }));
@@ -8659,14 +8678,14 @@ describe('model: populate:', function() {
 
       const nestedLayerSchema = Schema({ users: [ Number ] });
       nestedLayerSchema.virtual('users_$', {
-        ref: 'gh6488_User',
+        ref: 'User',
         localField: 'users',
         foreignField: 'employeeId'
       });
 
       const docArray = batchSchema.path('nested.events');
-      docArray.discriminator('gh6488_Clicked', Schema({ nestedLayer: nestedLayerSchema }));
-      docArray.discriminator('gh6488_Purchased', Schema({ purchased: String }));
+      docArray.discriminator('Clicked', Schema({ nestedLayer: nestedLayerSchema }));
+      docArray.discriminator('Purchased', Schema({ purchased: String }));
 
       const Batch = db.model('gh6488', batchSchema);
 
@@ -8674,8 +8693,8 @@ describe('model: populate:', function() {
       yield Batch.create({
         nested: {
           events: [
-            { kind: 'gh6488_Clicked', nestedLayer: { users: [1] } },
-            { kind: 'gh6488_Purchased', purchased: 'test' }
+            { kind: 'Clicked', nestedLayer: { users: [1] } },
+            { kind: 'Purchased', purchased: 'test' }
           ]
         }
       });
@@ -8726,11 +8745,11 @@ describe('model: populate:', function() {
     before(function() {
       const authorSchema = Schema({ name: String });
       const subSchema = Schema({
-        author: { type: Schema.Types.ObjectId, ref: 'gh8247_Author' },
+        author: { type: Schema.Types.ObjectId, ref: 'Author' },
         comment: String
       });
       const pageSchema = Schema({ title: String, comments: [subSchema] });
-      Author = db.model('gh8247_Author', authorSchema);
+      Author = db.model('Author', authorSchema);
       Page = db.model('gh8247_Page', pageSchema);
     });
 
@@ -8911,17 +8930,17 @@ describe('model: populate:', function() {
         ref: 'gh8432_Companies'
       }
     });
-    const User = db.model('gh8432_Users', userSchema);
+    const User = db.model('User', userSchema);
 
     const fileSchema = new mongoose.Schema({
       _id: String,
       uploaderId: {
         type: mongoose.ObjectId,
-        ref: 'gh8432_Users'
+        ref: 'User'
       }
     }, { toObject: { virtuals: true }, toJSON: { virtuals: true } });
     fileSchema.virtual('uploadedBy', {
-      ref: 'gh8432_Users',
+      ref: 'User',
       localField: 'uploaderId',
       foreignField: '_id',
       justOne: true
@@ -9063,15 +9082,15 @@ describe('model: populate:', function() {
 
     const parentSchema = Schema({ name: String });
     parentSchema.virtual('childCount', {
-      ref: 'gh8475_Child',
+      ref: 'Child',
       localField: '_id',
       foreignField: 'parentId',
       count: true,
       match: { deleted: { $ne: true } }
     });
 
-    const Child = db.model('gh8475_Child', childSchema);
-    const Parent = db.model('gh8475_Parent', parentSchema);
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
       const p = yield Parent.create({ name: 'test' });

From d58e38d03221341f109a16cd0a0a4b053ee65a19 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 11:34:29 -0500
Subject: [PATCH 0338/2348] test: fix a couple tests re: #8481

---
 test/model.populate.test.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index bd71e1649ee..6ee6fa33404 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -5884,6 +5884,7 @@ describe('model: populate:', function() {
           justOne: true
         });
 
+        db.deleteModel(/.*/);
         const Author = db.model('Author', AuthorSchema);
         const Book = db.model('Book', BookSchema);
 
@@ -8742,7 +8743,7 @@ describe('model: populate:', function() {
     let Author;
     let Page;
 
-    before(function() {
+    beforeEach(function() {
       const authorSchema = Schema({ name: String });
       const subSchema = Schema({
         author: { type: Schema.Types.ObjectId, ref: 'Author' },
@@ -8753,7 +8754,7 @@ describe('model: populate:', function() {
       Page = db.model('gh8247_Page', pageSchema);
     });
 
-    this.beforeEach(() => co(function*() {
+    beforeEach(() => co(function*() {
       yield Author.deleteMany({});
       yield Page.deleteMany({});
     }));

From 613142e5c09c9c8e53abb1abab3c3bfb1113d12b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 11:35:34 -0500
Subject: [PATCH 0339/2348] style: fix lint

---
 test/model.populate.test.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6ee6fa33404..6b54146bb58 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -17,8 +17,6 @@ const Schema = mongoose.Schema;
 const ObjectId = Schema.ObjectId;
 const DocObjectId = mongoose.Types.ObjectId;
 
-const collectionName = 'model.populate';
-
 /**
  * Tests.
  */

From 24f0b9dd55a4eb32a2205926c2e2aa41a75a81a0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 11:43:05 -0500
Subject: [PATCH 0340/2348] test: fix more tests re: #8481

---
 test/model.populate.test.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6b54146bb58..77a50f2ec86 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -6886,6 +6886,7 @@ describe('model: populate:', function() {
           justOne: false
         });
 
+        db.deleteModel(/.*/);
         const User = db.model('User', userSchema);
         const Teacher = db.model('gh6528_Teacher', teachSchema);
         const Post = db.model('Post', postSchema);
@@ -7095,6 +7096,7 @@ describe('model: populate:', function() {
       it('handles virtual embedded discriminator underneath single nested (gh-6571)', co.wrap(function*() {
         // Generate Users Model
         const userSchema = new Schema({ id: Number, name: String });
+        db.deleteModel(/.*/);
         const User = db.model('User', userSchema);
 
         // Generate Product Model
@@ -7304,7 +7306,8 @@ describe('model: populate:', function() {
       user.roomId = room._id;
       room.officeId = office._id;
 
-      return Promise.all([user.save(), office.save(), room.save()]);
+      return User.deleteMany({}).
+        then(() => Promise.all([user.save(), office.save(), room.save()]));
     });
 
     it('document, and subdocuments are not lean by default', function() {

From a076c889cddcacd3c592d9ee43509c4fbd7ad27a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jan 2020 14:45:40 -0500
Subject: [PATCH 0341/2348] chore: release 5.8.5

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 52ae23d2080..0a8d686a00e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.8.5 / 2020-01-06
+==================
+ * fix(document): throw error when running `validate()` multiple times on the same document #8468
+ * fix(model): ensure deleteOne() and deleteMany() set discriminator filter even if no conditions passed #8471
+ * fix(document): allow pre('validate') hooks to throw errors with `name = 'ValidationError'` #8466
+ * fix(update): move top level $set of immutable properties to $setOnInsert so upserting with immutable properties actually sets the property #8467
+ * fix(document): avoid double-running validators on single nested subdocs within single nested subdocs #8468
+ * fix(populate): support top-level match option for virtual populate #8475
+ * fix(model): avoid applying skip when populating virtual with count #8476
+
 5.8.4 / 2020-01-02
 ==================
  * fix(populate): ensure populate virtual gets set to empty array if `localField` is undefined in the database #8455
diff --git a/package.json b/package.json
index 3c92a0c22e0..6a28d64f39f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.5-pre",
+  "version": "5.8.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 6a8b38144df41955b09a599635128f1c5a0cfdc2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 21:40:01 -0500
Subject: [PATCH 0342/2348] chore: add .config.js to gitignore and npmignore

---
 .gitignore | 2 ++
 .npmignore | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/.gitignore b/.gitignore
index d9ae398e527..28577b8fb07 100644
--- a/.gitignore
+++ b/.gitignore
@@ -36,3 +36,5 @@ tools/31*
 docs/*.html
 
 test/files/main.js
+
+.config.js
\ No newline at end of file
diff --git a/.npmignore b/.npmignore
index da4b657952c..c69c61dc1b7 100644
--- a/.npmignore
+++ b/.npmignore
@@ -19,3 +19,5 @@ tools/31*
 data/
 
 test/files
+
+.config.js
\ No newline at end of file

From 803090d3e31d780b7b9533dda85791143929e1ba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 21:40:55 -0500
Subject: [PATCH 0343/2348] fix(schema): make aliases handle
 mongoose-lean-virtuals

Backport fix for #6069 and vkarpov15/mongoose-lean-virtuals#6
---
 lib/schema.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 5ed761ad677..ca4dc3c2d6a 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -143,16 +143,20 @@ function aliasFields(schema) {
 
     if (alias) {
       if ('string' === typeof alias && alias.length > 0) {
-        if (schema.aliases[alias])
+        if (schema.aliases[alias]) {
           throw new Error('Duplicate alias, alias ' + alias + ' is used more than once');
-        else
+        } else {
           schema.aliases[alias] = prop;
+        }
 
         schema
           .virtual(alias)
           .get((function(p) {
             return function() {
-              return this.get(p);
+              if (typeof this.get === 'function') {
+                return this.get(p);
+              }
+              return this[p];
             };
           })(prop))
           .set((function(p) {

From 0e65e6e8b472b927fa0fe16c142c735d65a4c05e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 21:42:21 -0500
Subject: [PATCH 0344/2348] chore: release 4.13.20

---
 History.md   | 4 ++++
 package.json | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f53d01bcfb5..294b1e0ce5c 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,7 @@
+4.13.20 / 2020-01-07
+====================
+ * fix(schema): make aliases handle mongoose-lean-virtuals #6069
+
 4.13.19 / 2019-07-02
 ====================
  * fix(aggregate): make `setOptions()` work as advertised #7950 #6011 [cdimitroulas](https://github.com/cdimitroulas)
diff --git a/package.json b/package.json
index 8b37d63b100..82f996b592a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "4.13.19",
+  "version": "4.13.20",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 91f95dad75fc6d99630b9f492914e0399b85bf68 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 21:50:19 -0500
Subject: [PATCH 0345/2348] chore: run consistent mongod version in tests

---
 .travis.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.travis.yml b/.travis.yml
index 25ffa13582c..6dc507e540b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,6 +17,7 @@ before_script:
   - mkdir -p ./data/db/27000
   - printf "\n--timeout 8000" >> ./test/mocha.opts
   - ./mongodb-linux-x86_64-2.6.11/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+  - export PATH=`pwd`/mongodb-linux-x86_64-2.6.11/bin/:$PATH
   - sleep 3
 script:
   - npm test

From 4a55040465eeeecdc0e712a78cab975dba4f8c3f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 21:59:16 -0500
Subject: [PATCH 0346/2348] chore: remove problematic mongoose-long dep and use
 mongodb 3.4 in tests

---
 .travis.yml               |    8 +-
 package-lock.json         | 1954 ++++++++++++++++++-------------------
 package.json              |    1 -
 test/model.update.test.js |   20 -
 4 files changed, 936 insertions(+), 1047 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 6dc507e540b..02eda0a1aeb 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,13 +11,13 @@ node_js:
   - "0.10"
   - "iojs"
 before_script:
-  - wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.6.11.tgz
-  - tar -zxvf mongodb-linux-x86_64-2.6.11.tgz
+  - wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.4.23.tgz
+  - tar -zxvf mongodb-linux-x86_64-3.4.23.tgz
   - mkdir -p ./data/db/27017
   - mkdir -p ./data/db/27000
   - printf "\n--timeout 8000" >> ./test/mocha.opts
-  - ./mongodb-linux-x86_64-2.6.11/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
-  - export PATH=`pwd`/mongodb-linux-x86_64-2.6.11/bin/:$PATH
+  - ./mongodb-linux-x86_64-3.4.23/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+  - export PATH=`pwd`/mongodb-linux-x86_64-3.4.23/bin/:$PATH
   - sleep 3
 script:
   - npm test
diff --git a/package-lock.json b/package-lock.json
index e020a0a1130..26bd7546d2f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "mongoose",
-  "version": "4.13.19",
+  "version": "4.13.20",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -11,19 +11,19 @@
       "dev": true
     },
     "accepts": {
-      "version": "1.3.4",
-      "resolved": "https://registry.npmjs.org/accepts/-/accepts-1.3.4.tgz",
-      "integrity": "sha1-hiRnWMfdbSGmR0/whKR0DsBesh8=",
+      "version": "1.3.7",
+      "resolved": "https://registry.npmjs.org/accepts/-/accepts-1.3.7.tgz",
+      "integrity": "sha512-Il80Qs2WjYlJIBNzNkK6KYqlVMTbZLXgHx2oT0pU/fjRHyEp+PEfEPY0R3WCwAGVOtauxh1hOxNgIf5bv7dQpA==",
       "dev": true,
       "requires": {
-        "mime-types": "2.1.17",
-        "negotiator": "0.6.1"
+        "mime-types": "~2.1.24",
+        "negotiator": "0.6.2"
       }
     },
     "acorn": {
-      "version": "5.1.2",
-      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.1.2.tgz",
-      "integrity": "sha512-o96FZLJBPY1lvTuJylGA9Bk3t/GKPPJG8H0ydQQl01crzwJgspa4AEIq/pVTXigmK0PHVQhiAtn8WMBLL9D2WA==",
+      "version": "5.7.3",
+      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.3.tgz",
+      "integrity": "sha512-T/zvzYRfbVojPWahDsE5evJdHb3oJoQfFbsrKM7w5Zcs++Tr257tia3BmMP8XYVjp1S9RZXQMh7gao96BlqZOw==",
       "dev": true
     },
     "acorn-es7-plugin": {
@@ -38,7 +38,7 @@
       "integrity": "sha1-r9+UiPsezvyDSPb7IvRk4ypYs2s=",
       "dev": true,
       "requires": {
-        "acorn": "3.3.0"
+        "acorn": "^3.0.4"
       },
       "dependencies": {
         "acorn": {
@@ -81,8 +81,8 @@
       "integrity": "sha1-gv+wKynmYq5TvcIK8VlHcGc5xTY=",
       "dev": true,
       "requires": {
-        "co": "4.6.0",
-        "json-stable-stringify": "1.0.1"
+        "co": "^4.6.0",
+        "json-stable-stringify": "^1.0.1"
       }
     },
     "ajv-keywords": {
@@ -97,16 +97,17 @@
       "integrity": "sha1-DNkKVhCT810KmSVsIrcGlDP60Rc=",
       "dev": true,
       "requires": {
-        "kind-of": "3.2.2",
-        "longest": "1.0.1",
-        "repeat-string": "1.6.1"
+        "kind-of": "^3.0.2",
+        "longest": "^1.0.1",
+        "repeat-string": "^1.5.2"
       }
     },
     "amdefine": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/amdefine/-/amdefine-1.0.1.tgz",
       "integrity": "sha1-SlKCrBZHKek2Gbz9OtFR+BfOkfU=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "ansi-escapes": {
       "version": "1.4.0",
@@ -127,12 +128,12 @@
       "dev": true
     },
     "argparse": {
-      "version": "1.0.9",
-      "resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.9.tgz",
-      "integrity": "sha1-c9g7wmP4bpf4zE9rrhsOkKfSLIY=",
+      "version": "1.0.10",
+      "resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.10.tgz",
+      "integrity": "sha512-o5Roy6tNG4SL/FOkCAN6RzjiakZS25RLYFrcMttJqbdd8BWrnA+fGz57iN5Pb06pvBGvl5gQ0B48dJlslXvoTg==",
       "dev": true,
       "requires": {
-        "sprintf-js": "1.0.3"
+        "sprintf-js": "~1.0.2"
       }
     },
     "array-filter": {
@@ -147,33 +148,19 @@
       "integrity": "sha1-ml9pkFGx5wczKPKgCJaLZOopVdI=",
       "dev": true
     },
-    "array-union": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/array-union/-/array-union-1.0.2.tgz",
-      "integrity": "sha1-mjRBDk9OPaI96jdb5b5w8kd47Dk=",
-      "dev": true,
-      "requires": {
-        "array-uniq": "1.0.3"
-      }
-    },
-    "array-uniq": {
-      "version": "1.0.3",
-      "resolved": "https://registry.npmjs.org/array-uniq/-/array-uniq-1.0.3.tgz",
-      "integrity": "sha1-r2rId6Jcx/dOBYiUdThY39sk/bY=",
-      "dev": true
-    },
-    "arrify": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/arrify/-/arrify-1.0.1.tgz",
-      "integrity": "sha1-iYUI2iIm84DfkEcoRWhJwVAaSw0=",
-      "dev": true
-    },
     "async": {
       "version": "2.6.0",
       "resolved": "https://registry.npmjs.org/async/-/async-2.6.0.tgz",
       "integrity": "sha512-xAfGg1/NTLBBKlHFmnd7PlmUW9KhVQIUuSrYem9xzFUZy13ScvtyGGejaae9iAVRiRq9+Cx7DPFaAAhCpyxyPw==",
       "requires": {
-        "lodash": "4.17.10"
+        "lodash": "^4.14.0"
+      },
+      "dependencies": {
+        "lodash": {
+          "version": "4.17.15",
+          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.15.tgz",
+          "integrity": "sha512-8xOcRHvCjnocdS5cpwXQXVzmmh5e5+saE2QGoeQmbKmRS6J3VQppPOIt0MnmE+4xlZoumy0GPG0D0MVIQbNA1A=="
+        }
       }
     },
     "babel-code-frame": {
@@ -182,44 +169,38 @@
       "integrity": "sha1-Y/1D99weO7fONZR9uP42mj9Yx0s=",
       "dev": true,
       "requires": {
-        "chalk": "1.1.3",
-        "esutils": "2.0.2",
-        "js-tokens": "3.0.2"
+        "chalk": "^1.1.3",
+        "esutils": "^2.0.2",
+        "js-tokens": "^3.0.2"
       }
     },
     "babel-core": {
-      "version": "6.26.0",
-      "resolved": "https://registry.npmjs.org/babel-core/-/babel-core-6.26.0.tgz",
-      "integrity": "sha1-rzL3izGm/O8RnIew/Y2XU/A6C7g=",
-      "dev": true,
-      "requires": {
-        "babel-code-frame": "6.26.0",
-        "babel-generator": "6.26.0",
-        "babel-helpers": "6.24.1",
-        "babel-messages": "6.23.0",
-        "babel-register": "6.26.0",
-        "babel-runtime": "6.26.0",
-        "babel-template": "6.26.0",
-        "babel-traverse": "6.26.0",
-        "babel-types": "6.26.0",
-        "babylon": "6.18.0",
-        "convert-source-map": "1.5.0",
-        "debug": "2.6.9",
-        "json5": "0.5.1",
-        "lodash": "4.17.4",
-        "minimatch": "3.0.4",
-        "path-is-absolute": "1.0.1",
-        "private": "0.1.7",
-        "slash": "1.0.0",
-        "source-map": "0.5.7"
+      "version": "6.26.3",
+      "resolved": "https://registry.npmjs.org/babel-core/-/babel-core-6.26.3.tgz",
+      "integrity": "sha512-6jyFLuDmeidKmUEb3NM+/yawG0M2bDZ9Z1qbZP59cyHLz8kYGKYwpJP0UwUKKUiTRNvxfLesJnTedqczP7cTDA==",
+      "dev": true,
+      "requires": {
+        "babel-code-frame": "^6.26.0",
+        "babel-generator": "^6.26.0",
+        "babel-helpers": "^6.24.1",
+        "babel-messages": "^6.23.0",
+        "babel-register": "^6.26.0",
+        "babel-runtime": "^6.26.0",
+        "babel-template": "^6.26.0",
+        "babel-traverse": "^6.26.0",
+        "babel-types": "^6.26.0",
+        "babylon": "^6.18.0",
+        "convert-source-map": "^1.5.1",
+        "debug": "^2.6.9",
+        "json5": "^0.5.1",
+        "lodash": "^4.17.4",
+        "minimatch": "^3.0.4",
+        "path-is-absolute": "^1.0.1",
+        "private": "^0.1.8",
+        "slash": "^1.0.0",
+        "source-map": "^0.5.7"
       },
       "dependencies": {
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
-          "dev": true
-        },
         "source-map": {
           "version": "0.5.7",
           "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.5.7.tgz",
@@ -229,27 +210,21 @@
       }
     },
     "babel-generator": {
-      "version": "6.26.0",
-      "resolved": "https://registry.npmjs.org/babel-generator/-/babel-generator-6.26.0.tgz",
-      "integrity": "sha1-rBriAHC3n248odMmlhMFN3TyDcU=",
-      "dev": true,
-      "requires": {
-        "babel-messages": "6.23.0",
-        "babel-runtime": "6.26.0",
-        "babel-types": "6.26.0",
-        "detect-indent": "4.0.0",
-        "jsesc": "1.3.0",
-        "lodash": "4.17.4",
-        "source-map": "0.5.7",
-        "trim-right": "1.0.1"
+      "version": "6.26.1",
+      "resolved": "https://registry.npmjs.org/babel-generator/-/babel-generator-6.26.1.tgz",
+      "integrity": "sha512-HyfwY6ApZj7BYTcJURpM5tznulaBvyio7/0d4zFOeMPUmfxkCjHocCuoLa2SAGzBI8AREcH3eP3758F672DppA==",
+      "dev": true,
+      "requires": {
+        "babel-messages": "^6.23.0",
+        "babel-runtime": "^6.26.0",
+        "babel-types": "^6.26.0",
+        "detect-indent": "^4.0.0",
+        "jsesc": "^1.3.0",
+        "lodash": "^4.17.4",
+        "source-map": "^0.5.7",
+        "trim-right": "^1.0.1"
       },
       "dependencies": {
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
-          "dev": true
-        },
         "source-map": {
           "version": "0.5.7",
           "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.5.7.tgz",
@@ -264,8 +239,8 @@
       "integrity": "sha1-NHHenK7DiOXIUOWX5Yom3fN2ArI=",
       "dev": true,
       "requires": {
-        "babel-runtime": "6.26.0",
-        "babel-template": "6.26.0"
+        "babel-runtime": "^6.22.0",
+        "babel-template": "^6.24.1"
       }
     },
     "babel-messages": {
@@ -274,7 +249,7 @@
       "integrity": "sha1-8830cDhYA1sqKVHG7F7fbGLyYw4=",
       "dev": true,
       "requires": {
-        "babel-runtime": "6.26.0"
+        "babel-runtime": "^6.22.0"
       }
     },
     "babel-polyfill": {
@@ -283,9 +258,9 @@
       "integrity": "sha1-N5k3q8Z9eJWXCtxiHyhM2WbPIVM=",
       "dev": true,
       "requires": {
-        "babel-runtime": "6.26.0",
-        "core-js": "2.5.1",
-        "regenerator-runtime": "0.10.5"
+        "babel-runtime": "^6.26.0",
+        "core-js": "^2.5.0",
+        "regenerator-runtime": "^0.10.5"
       },
       "dependencies": {
         "regenerator-runtime": {
@@ -302,21 +277,13 @@
       "integrity": "sha1-btAhFz4vy0htestFxgCahW9kcHE=",
       "dev": true,
       "requires": {
-        "babel-core": "6.26.0",
-        "babel-runtime": "6.26.0",
-        "core-js": "2.5.1",
-        "home-or-tmp": "2.0.0",
-        "lodash": "4.17.4",
-        "mkdirp": "0.5.1",
-        "source-map-support": "0.4.18"
-      },
-      "dependencies": {
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
-          "dev": true
-        }
+        "babel-core": "^6.26.0",
+        "babel-runtime": "^6.26.0",
+        "core-js": "^2.5.0",
+        "home-or-tmp": "^2.0.0",
+        "lodash": "^4.17.4",
+        "mkdirp": "^0.5.1",
+        "source-map-support": "^0.4.15"
       }
     },
     "babel-runtime": {
@@ -325,8 +292,8 @@
       "integrity": "sha1-llxwWGaOgrVde/4E/yM3vItWR/4=",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "regenerator-runtime": "0.11.0"
+        "core-js": "^2.4.0",
+        "regenerator-runtime": "^0.11.0"
       }
     },
     "babel-template": {
@@ -335,19 +302,11 @@
       "integrity": "sha1-3gPi0WOWsGn0bdn/+FIfsaDjXgI=",
       "dev": true,
       "requires": {
-        "babel-runtime": "6.26.0",
-        "babel-traverse": "6.26.0",
-        "babel-types": "6.26.0",
-        "babylon": "6.18.0",
-        "lodash": "4.17.4"
-      },
-      "dependencies": {
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
-          "dev": true
-        }
+        "babel-runtime": "^6.26.0",
+        "babel-traverse": "^6.26.0",
+        "babel-types": "^6.26.0",
+        "babylon": "^6.18.0",
+        "lodash": "^4.17.4"
       }
     },
     "babel-traverse": {
@@ -356,15 +315,15 @@
       "integrity": "sha1-RqnL1+3MYsjlwGTi0tjQ9ANXZu4=",
       "dev": true,
       "requires": {
-        "babel-code-frame": "6.26.0",
-        "babel-messages": "6.23.0",
-        "babel-runtime": "6.26.0",
-        "babel-types": "6.26.0",
-        "babylon": "6.18.0",
-        "debug": "2.6.9",
-        "globals": "9.18.0",
-        "invariant": "2.2.2",
-        "lodash": "4.17.4"
+        "babel-code-frame": "^6.26.0",
+        "babel-messages": "^6.23.0",
+        "babel-runtime": "^6.26.0",
+        "babel-types": "^6.26.0",
+        "babylon": "^6.18.0",
+        "debug": "^2.6.8",
+        "globals": "^9.18.0",
+        "invariant": "^2.2.2",
+        "lodash": "^4.17.4"
       },
       "dependencies": {
         "globals": {
@@ -372,12 +331,6 @@
           "resolved": "https://registry.npmjs.org/globals/-/globals-9.18.0.tgz",
           "integrity": "sha512-S0nG3CLEQiY/ILxqtztTWH/3iRRdyBLw6KMDxnKMchrtbj2OFmehVh0WUCfW3DUrIgx/qFrJPICrq4Z4sTR9UQ==",
           "dev": true
-        },
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
-          "dev": true
         }
       }
     },
@@ -387,18 +340,10 @@
       "integrity": "sha1-o7Bz+Uq0nrb6Vc1lInozQ4BjJJc=",
       "dev": true,
       "requires": {
-        "babel-runtime": "6.26.0",
-        "esutils": "2.0.2",
-        "lodash": "4.17.4",
-        "to-fast-properties": "1.0.3"
-      },
-      "dependencies": {
-        "lodash": {
-          "version": "4.17.4",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.4.tgz",
-          "integrity": "sha1-eCA6TRwyiuHYbcpkYONptX9AVa4=",
-          "dev": true
-        }
+        "babel-runtime": "^6.26.0",
+        "esutils": "^2.0.2",
+        "lodash": "^4.17.4",
+        "to-fast-properties": "^1.0.3"
       }
     },
     "babylon": {
@@ -419,8 +364,8 @@
       "integrity": "sha1-BnbYLlYNgtLzF/gs8IWEg5Vae/4=",
       "dev": true,
       "requires": {
-        "lodash": "4.17.10",
-        "platform": "1.3.4"
+        "lodash": "^4.16.4",
+        "platform": "^1.3.1"
       }
     },
     "bluebird": {
@@ -429,30 +374,30 @@
       "integrity": "sha1-eRQg1/VR7qKJdFOop3ZT+WYG1nw="
     },
     "body-parser": {
-      "version": "1.18.2",
-      "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.18.2.tgz",
-      "integrity": "sha1-h2eKGdhLR9hZuDGZvVm84iKxBFQ=",
+      "version": "1.19.0",
+      "resolved": "https://registry.npmjs.org/body-parser/-/body-parser-1.19.0.tgz",
+      "integrity": "sha512-dhEPs72UPbDnAQJ9ZKMNTP6ptJaionhP5cBb541nXPlW60Jepo9RV/a4fX4XWW9CuFNK22krhrj1+rgzifNCsw==",
       "dev": true,
       "requires": {
-        "bytes": "3.0.0",
-        "content-type": "1.0.4",
+        "bytes": "3.1.0",
+        "content-type": "~1.0.4",
         "debug": "2.6.9",
-        "depd": "1.1.1",
-        "http-errors": "1.6.2",
-        "iconv-lite": "0.4.19",
-        "on-finished": "2.3.0",
-        "qs": "6.5.1",
-        "raw-body": "2.3.2",
-        "type-is": "1.6.15"
+        "depd": "~1.1.2",
+        "http-errors": "1.7.2",
+        "iconv-lite": "0.4.24",
+        "on-finished": "~2.3.0",
+        "qs": "6.7.0",
+        "raw-body": "2.4.0",
+        "type-is": "~1.6.17"
       }
     },
     "brace-expansion": {
-      "version": "1.1.8",
-      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.8.tgz",
-      "integrity": "sha1-wHshHHyVLsH479Uad+8NHTmQopI=",
+      "version": "1.1.11",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
+      "integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
       "dev": true,
       "requires": {
-        "balanced-match": "1.0.0",
+        "balanced-match": "^1.0.0",
         "concat-map": "0.0.1"
       }
     },
@@ -463,9 +408,15 @@
       "dev": true
     },
     "bson": {
-      "version": "1.0.4",
-      "resolved": "https://registry.npmjs.org/bson/-/bson-1.0.4.tgz",
-      "integrity": "sha1-k8ENOeqltYQVy8QFLz5T5WKwtyw="
+      "version": "1.0.9",
+      "resolved": "https://registry.npmjs.org/bson/-/bson-1.0.9.tgz",
+      "integrity": "sha512-IQX9/h7WdMBIW/q/++tGd+emQr0XMdeZ6icnT/74Xk9fnabWn+gZgpE+9V+gujL3hhJOoNrnDVY7tWdzc7NUTg=="
+    },
+    "buffer-from": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/buffer-from/-/buffer-from-1.1.1.tgz",
+      "integrity": "sha512-MQcXEUbCKtEo7bhqEs6560Hyd4XaovZlO/k9V3hjVUF/zwW7KBVdSK4gIt/bzwS9MbR5qob+F5jusZsb0YQK2A==",
+      "dev": true
     },
     "buffer-shims": {
       "version": "1.0.0",
@@ -473,9 +424,9 @@
       "integrity": "sha1-mXjOMXOIxkmth5MCjDR37wRKi1E="
     },
     "bytes": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/bytes/-/bytes-3.0.0.tgz",
-      "integrity": "sha1-0ygVQE1olpn4Wk6k+odV3ROpYEg=",
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/bytes/-/bytes-3.1.0.tgz",
+      "integrity": "sha512-zauLjrfCG+xvoyaqLoV8bLVXXNGC4JqlxFCutSDWA6fJrTo2ZuvLYTqZ7aHBLZSMOopbzwv8f+wZcVzfVTI2Dg==",
       "dev": true
     },
     "call-signature": {
@@ -490,7 +441,7 @@
       "integrity": "sha1-lAhe9jWB7NPaqSREqP6U6CV3dR8=",
       "dev": true,
       "requires": {
-        "callsites": "0.2.0"
+        "callsites": "^0.2.0"
       }
     },
     "callsites": {
@@ -511,8 +462,8 @@
       "integrity": "sha1-qg0yYptu6XIgBBHL1EYckHvCt60=",
       "dev": true,
       "requires": {
-        "align-text": "0.1.4",
-        "lazy-cache": "1.0.4"
+        "align-text": "^0.1.3",
+        "lazy-cache": "^1.0.3"
       }
     },
     "chalk": {
@@ -521,11 +472,11 @@
       "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
       "dev": true,
       "requires": {
-        "ansi-styles": "2.2.1",
-        "escape-string-regexp": "1.0.5",
-        "has-ansi": "2.0.0",
-        "strip-ansi": "3.0.1",
-        "supports-color": "2.0.0"
+        "ansi-styles": "^2.2.1",
+        "escape-string-regexp": "^1.0.2",
+        "has-ansi": "^2.0.0",
+        "strip-ansi": "^3.0.0",
+        "supports-color": "^2.0.0"
       }
     },
     "circular-json": {
@@ -540,7 +491,7 @@
       "integrity": "sha1-ZNo/fValRBLll5S9Ytw1KV6PKYc=",
       "dev": true,
       "requires": {
-        "restore-cursor": "1.0.1"
+        "restore-cursor": "^1.0.1"
       }
     },
     "cli-width": {
@@ -555,8 +506,8 @@
       "integrity": "sha1-S0dXYP+AJkx2LDoXGQMukcf+oNE=",
       "dev": true,
       "requires": {
-        "center-align": "0.1.3",
-        "right-align": "0.1.3",
+        "center-align": "^0.1.1",
+        "right-align": "^0.1.1",
         "wordwrap": "0.0.2"
       },
       "dependencies": {
@@ -580,16 +531,16 @@
       "integrity": "sha1-DQcLTQQ6W+ozovGkDi7bPZpMz3c=",
       "dev": true
     },
-    "coffee-script": {
+    "coffeescript": {
       "version": "1.12.7",
-      "resolved": "https://registry.npmjs.org/coffee-script/-/coffee-script-1.12.7.tgz",
-      "integrity": "sha512-fLeEhqwymYat/MpTPUjSKHVYYl0ec2mOyALEMLmzr5i1isuG+6jfI2j2d5oBO3VIzgUXgBVIcOT9uH1TFxBckw==",
+      "resolved": "https://registry.npmjs.org/coffeescript/-/coffeescript-1.12.7.tgz",
+      "integrity": "sha512-pLXHFxQMPklVoEekowk8b3erNynC+DVJzChxS/LCBBgR6/8AJkHivkm//zbowcfc7BTCAjryuhx6gPqPRfsFoA==",
       "dev": true
     },
     "colors": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/colors/-/colors-1.1.2.tgz",
-      "integrity": "sha1-FopHAXVran9RoSzgyXv6KMCE7WM=",
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/colors/-/colors-1.4.0.tgz",
+      "integrity": "sha512-a+UqTh4kgZg/SlGvfbzDHpgRu7AAQOmmqRHJnxhRZICKFUT91brVhNNt58CMWU9PsBbv3PDCZUHbVxuDiH2mtA==",
       "dev": true
     },
     "commander": {
@@ -605,21 +556,25 @@
       "dev": true
     },
     "concat-stream": {
-      "version": "1.6.0",
-      "resolved": "https://registry.npmjs.org/concat-stream/-/concat-stream-1.6.0.tgz",
-      "integrity": "sha1-CqxmL9Ur54lk1VMvaUeE5wEQrPc=",
+      "version": "1.6.2",
+      "resolved": "https://registry.npmjs.org/concat-stream/-/concat-stream-1.6.2.tgz",
+      "integrity": "sha512-27HBghJxjiZtIk3Ycvn/4kbJk/1uZuJFfuPEns6LaEvpvG1f0hTea8lilrouyo9mVc2GWdcEZ8OLoGmSADlrCw==",
       "dev": true,
       "requires": {
-        "inherits": "2.0.3",
-        "readable-stream": "2.2.7",
-        "typedarray": "0.0.6"
+        "buffer-from": "^1.0.0",
+        "inherits": "^2.0.3",
+        "readable-stream": "^2.2.2",
+        "typedarray": "^0.0.6"
       }
     },
     "content-disposition": {
-      "version": "0.5.2",
-      "resolved": "https://registry.npmjs.org/content-disposition/-/content-disposition-0.5.2.tgz",
-      "integrity": "sha1-DPaLud318r55YcOoUXjLhdunjLQ=",
-      "dev": true
+      "version": "0.5.3",
+      "resolved": "https://registry.npmjs.org/content-disposition/-/content-disposition-0.5.3.tgz",
+      "integrity": "sha512-ExO0774ikEObIAEV9kDo50o+79VCUdEB6n6lzKgGwupcVeRlhrj3qGAfwq8G6uBJjkqLrhT0qEYFcWng8z1z0g==",
+      "dev": true,
+      "requires": {
+        "safe-buffer": "5.1.2"
+      }
     },
     "content-type": {
       "version": "1.0.4",
@@ -628,15 +583,18 @@
       "dev": true
     },
     "convert-source-map": {
-      "version": "1.5.0",
-      "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-1.5.0.tgz",
-      "integrity": "sha1-ms1whRxtXf3ZPZKC5e35SgP/RrU=",
-      "dev": true
+      "version": "1.7.0",
+      "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-1.7.0.tgz",
+      "integrity": "sha512-4FJkXzKXEDB1snCFZlLP4gpC3JILicCpGbzG9f9G7tGqGCzETQ2hWPrcinA9oU4wtf2biUaEH5065UnMeR33oA==",
+      "dev": true,
+      "requires": {
+        "safe-buffer": "~5.1.1"
+      }
     },
     "cookie": {
-      "version": "0.3.1",
-      "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.3.1.tgz",
-      "integrity": "sha1-5+Ch+e9DtMi6klxcWpboBtFoc7s=",
+      "version": "0.4.0",
+      "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.4.0.tgz",
+      "integrity": "sha512-+Hp8fLp57wnUSt0tY0tHEXh4voZRDnoIrZPqlo3DPiI4y9lwg/jqx+1Om94/W6ZaPDOUbnjOt/99w66zk+l1Xg==",
       "dev": true
     },
     "cookie-signature": {
@@ -646,9 +604,9 @@
       "dev": true
     },
     "core-js": {
-      "version": "2.5.1",
-      "resolved": "https://registry.npmjs.org/core-js/-/core-js-2.5.1.tgz",
-      "integrity": "sha1-rmh03GaTd4m4B1T/VCjfZoGcpQs=",
+      "version": "2.6.11",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-2.6.11.tgz",
+      "integrity": "sha512-5wjnpaT/3dV+XB4borEsnAYQchn00XSgTAWKDkEqv+K8KevjbzmofK6hfJ9TZIlpj2N0xQpazy7PiRQiWHqzWg==",
       "dev": true
     },
     "core-util-is": {
@@ -657,12 +615,13 @@
       "integrity": "sha1-tf1UIgqivFq1eqtxQMlAdUUDwac="
     },
     "d": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/d/-/d-1.0.0.tgz",
-      "integrity": "sha1-dUu1v+VUUdpppYuU1F9MWwRi1Y8=",
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/d/-/d-1.0.1.tgz",
+      "integrity": "sha512-m62ShEObQ39CfralilEQRjH6oAMtNCV1xJyEx5LpRYUVN+EviphDgUc/F3hnYbADmkiNs67Y+3ylmlG7Lnu+FA==",
       "dev": true,
       "requires": {
-        "es5-ext": "0.10.30"
+        "es5-ext": "^0.10.50",
+        "type": "^1.0.1"
       }
     },
     "debug": {
@@ -686,34 +645,18 @@
       "dev": true
     },
     "define-properties": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/define-properties/-/define-properties-1.1.2.tgz",
-      "integrity": "sha1-g6c/L+pWmJj7c3GTyPhzyvbUXJQ=",
-      "dev": true,
-      "requires": {
-        "foreach": "2.0.5",
-        "object-keys": "1.0.11"
-      }
-    },
-    "del": {
-      "version": "2.2.2",
-      "resolved": "https://registry.npmjs.org/del/-/del-2.2.2.tgz",
-      "integrity": "sha1-wSyYHQZ4RshLyvhiz/kw2Qf/0ag=",
+      "version": "1.1.3",
+      "resolved": "https://registry.npmjs.org/define-properties/-/define-properties-1.1.3.tgz",
+      "integrity": "sha512-3MqfYKj2lLzdMSf8ZIZE/V+Zuy+BgD6f164e8K2w7dgnpKArBDerGYpM46IYYcjnkdPNMjPk9A6VFB8+3SKlXQ==",
       "dev": true,
       "requires": {
-        "globby": "5.0.0",
-        "is-path-cwd": "1.0.0",
-        "is-path-in-cwd": "1.0.0",
-        "object-assign": "4.1.1",
-        "pify": "2.3.0",
-        "pinkie-promise": "2.0.1",
-        "rimraf": "2.6.2"
+        "object-keys": "^1.0.12"
       }
     },
     "depd": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/depd/-/depd-1.1.1.tgz",
-      "integrity": "sha1-V4O04cRZ8G+lyif5kfPQbnoxA1k=",
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/depd/-/depd-1.1.2.tgz",
+      "integrity": "sha1-m81S4UwJd2PnSbJ0xDRu0uVgtak=",
       "dev": true
     },
     "destroy": {
@@ -728,7 +671,7 @@
       "integrity": "sha1-920GQ1LN9Docts5hnE7jqUdd4gg=",
       "dev": true,
       "requires": {
-        "repeating": "2.0.1"
+        "repeating": "^2.0.0"
       }
     },
     "diff": {
@@ -738,9 +681,9 @@
       "dev": true
     },
     "diff-match-patch": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/diff-match-patch/-/diff-match-patch-1.0.0.tgz",
-      "integrity": "sha1-HMPIOkkNZ/ldkeOfatHy4Ia2MEg=",
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/diff-match-patch/-/diff-match-patch-1.0.4.tgz",
+      "integrity": "sha512-Uv3SW8bmH9nAtHKaKSanOQmj2DnlH65fUpcrMdfdaOxUG02QQ4YGZ8AE7kKOMisF7UqvOlGKVYWRvezdncW9lg==",
       "dev": true
     },
     "doctrine": {
@@ -749,8 +692,8 @@
       "integrity": "sha1-N53Ocw9hZvds76TmcHoVmwLFpvo=",
       "dev": true,
       "requires": {
-        "esutils": "2.0.2",
-        "isarray": "1.0.0"
+        "esutils": "^2.0.2",
+        "isarray": "^1.0.0"
       }
     },
     "dox": {
@@ -760,7 +703,7 @@
       "dev": true,
       "requires": {
         "commander": "0.6.1",
-        "github-flavored-markdown": "1.0.1"
+        "github-flavored-markdown": ">= 0.0.1"
       },
       "dependencies": {
         "commander": {
@@ -772,9 +715,9 @@
       }
     },
     "eastasianwidth": {
-      "version": "0.1.1",
-      "resolved": "https://registry.npmjs.org/eastasianwidth/-/eastasianwidth-0.1.1.tgz",
-      "integrity": "sha1-RNZW3p2kFWlEZzNTZfsxR7hXK3w=",
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/eastasianwidth/-/eastasianwidth-0.2.0.tgz",
+      "integrity": "sha512-I88TYZWc9XiYHRQ4/3c5rjjfgkjhLyW2luGIheGERbNQ6OY7yTybanSpDXZa8y7VUP9YmDcYa+eyq4ca7iLqWA==",
       "dev": true
     },
     "ee-first": {
@@ -784,50 +727,51 @@
       "dev": true
     },
     "empower": {
-      "version": "1.2.3",
-      "resolved": "https://registry.npmjs.org/empower/-/empower-1.2.3.tgz",
-      "integrity": "sha1-bw2nNEf07dg4/sXGAxOoi6XLhSs=",
+      "version": "1.3.1",
+      "resolved": "https://registry.npmjs.org/empower/-/empower-1.3.1.tgz",
+      "integrity": "sha512-uB6/ViBaawOO/uujFADTK3SqdYlxYNn+N4usK9MRKZ4Hbn/1QSy8k2PezxCA2/+JGbF8vd/eOfghZ90oOSDZCA==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "empower-core": "0.6.2"
+        "core-js": "^2.0.0",
+        "empower-core": "^1.2.0"
       }
     },
     "empower-core": {
-      "version": "0.6.2",
-      "resolved": "https://registry.npmjs.org/empower-core/-/empower-core-0.6.2.tgz",
-      "integrity": "sha1-Wt71ZgiOMfuoC6CjbfR9cJQWkUQ=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/empower-core/-/empower-core-1.2.0.tgz",
+      "integrity": "sha512-g6+K6Geyc1o6FdXs9HwrXleCFan7d66G5xSCfSF7x1mJDCes6t0om9lFQG3zOrzh3Bkb/45N0cZ5Gqsf7YrzGQ==",
       "dev": true,
       "requires": {
         "call-signature": "0.0.2",
-        "core-js": "2.5.1"
+        "core-js": "^2.0.0"
       }
     },
     "encodeurl": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/encodeurl/-/encodeurl-1.0.1.tgz",
-      "integrity": "sha1-eePVhlU0aQn+bw9Fpd5oEDspTSA=",
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/encodeurl/-/encodeurl-1.0.2.tgz",
+      "integrity": "sha1-rT/0yG7C0CkyL1oCw6mmBslbP1k=",
       "dev": true
     },
     "es5-ext": {
-      "version": "0.10.30",
-      "resolved": "https://registry.npmjs.org/es5-ext/-/es5-ext-0.10.30.tgz",
-      "integrity": "sha1-cUGhaDZpfbq/qq7uQUlc4p9SyTk=",
+      "version": "0.10.53",
+      "resolved": "https://registry.npmjs.org/es5-ext/-/es5-ext-0.10.53.tgz",
+      "integrity": "sha512-Xs2Stw6NiNHWypzRTY1MtaG/uJlwCk8kH81920ma8mvN8Xq1gsfhZvpkImLQArw8AHnv8MT2I45J3c0R8slE+Q==",
       "dev": true,
       "requires": {
-        "es6-iterator": "2.0.1",
-        "es6-symbol": "3.1.1"
+        "es6-iterator": "~2.0.3",
+        "es6-symbol": "~3.1.3",
+        "next-tick": "~1.0.0"
       }
     },
     "es6-iterator": {
-      "version": "2.0.1",
-      "resolved": "https://registry.npmjs.org/es6-iterator/-/es6-iterator-2.0.1.tgz",
-      "integrity": "sha1-jjGcnwRTv1ddN0lAplWSDlnKVRI=",
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/es6-iterator/-/es6-iterator-2.0.3.tgz",
+      "integrity": "sha1-p96IkUGgWpSwhUQDstCg+/qY87c=",
       "dev": true,
       "requires": {
-        "d": "1.0.0",
-        "es5-ext": "0.10.30",
-        "es6-symbol": "3.1.1"
+        "d": "1",
+        "es5-ext": "^0.10.35",
+        "es6-symbol": "^3.1.1"
       }
     },
     "es6-map": {
@@ -836,12 +780,12 @@
       "integrity": "sha1-kTbgUD3MBqMBaQ8LsU/042TpSfA=",
       "dev": true,
       "requires": {
-        "d": "1.0.0",
-        "es5-ext": "0.10.30",
-        "es6-iterator": "2.0.1",
-        "es6-set": "0.1.5",
-        "es6-symbol": "3.1.1",
-        "event-emitter": "0.3.5"
+        "d": "1",
+        "es5-ext": "~0.10.14",
+        "es6-iterator": "~2.0.1",
+        "es6-set": "~0.1.5",
+        "es6-symbol": "~3.1.1",
+        "event-emitter": "~0.3.5"
       }
     },
     "es6-promise": {
@@ -855,33 +799,45 @@
       "integrity": "sha1-0rPsXU2ADO2BjbU40ol02wpzzLE=",
       "dev": true,
       "requires": {
-        "d": "1.0.0",
-        "es5-ext": "0.10.30",
-        "es6-iterator": "2.0.1",
+        "d": "1",
+        "es5-ext": "~0.10.14",
+        "es6-iterator": "~2.0.1",
         "es6-symbol": "3.1.1",
-        "event-emitter": "0.3.5"
+        "event-emitter": "~0.3.5"
+      },
+      "dependencies": {
+        "es6-symbol": {
+          "version": "3.1.1",
+          "resolved": "https://registry.npmjs.org/es6-symbol/-/es6-symbol-3.1.1.tgz",
+          "integrity": "sha1-vwDvT9q2uhtG7Le2KbTH7VcVzHc=",
+          "dev": true,
+          "requires": {
+            "d": "1",
+            "es5-ext": "~0.10.14"
+          }
+        }
       }
     },
     "es6-symbol": {
-      "version": "3.1.1",
-      "resolved": "https://registry.npmjs.org/es6-symbol/-/es6-symbol-3.1.1.tgz",
-      "integrity": "sha1-vwDvT9q2uhtG7Le2KbTH7VcVzHc=",
+      "version": "3.1.3",
+      "resolved": "https://registry.npmjs.org/es6-symbol/-/es6-symbol-3.1.3.tgz",
+      "integrity": "sha512-NJ6Yn3FuDinBaBRWl/q5X/s4koRHBrgKAu+yGI6JCBeiu3qrcbJhwT2GeR/EXVfylRk8dpQVJoLEFhK+Mu31NA==",
       "dev": true,
       "requires": {
-        "d": "1.0.0",
-        "es5-ext": "0.10.30"
+        "d": "^1.0.1",
+        "ext": "^1.1.2"
       }
     },
     "es6-weak-map": {
-      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/es6-weak-map/-/es6-weak-map-2.0.2.tgz",
-      "integrity": "sha1-XjqzIlH/0VOKH45f+hNXdy+S2W8=",
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/es6-weak-map/-/es6-weak-map-2.0.3.tgz",
+      "integrity": "sha512-p5um32HOTO1kP+w7PRnB+5lQ43Z6muuMuIMffvDN8ZB4GcnjLBV6zGStpbASIMk4DCAvEaamhe2zhyCb/QXXsA==",
       "dev": true,
       "requires": {
-        "d": "1.0.0",
-        "es5-ext": "0.10.30",
-        "es6-iterator": "2.0.1",
-        "es6-symbol": "3.1.1"
+        "d": "1",
+        "es5-ext": "^0.10.46",
+        "es6-iterator": "^2.0.3",
+        "es6-symbol": "^3.1.1"
       }
     },
     "escape-html": {
@@ -902,11 +858,11 @@
       "integrity": "sha1-WltTr0aTEQvrsIZ6o0MN07cKEBg=",
       "dev": true,
       "requires": {
-        "esprima": "2.7.3",
-        "estraverse": "1.9.3",
-        "esutils": "2.0.2",
-        "optionator": "0.8.2",
-        "source-map": "0.2.0"
+        "esprima": "^2.7.1",
+        "estraverse": "^1.9.1",
+        "esutils": "^2.0.2",
+        "optionator": "^0.8.1",
+        "source-map": "~0.2.0"
       },
       "dependencies": {
         "esprima": {
@@ -929,10 +885,10 @@
       "integrity": "sha1-4Bl16BJ4GhY6ba392AOY3GTIicM=",
       "dev": true,
       "requires": {
-        "es6-map": "0.1.5",
-        "es6-weak-map": "2.0.2",
-        "esrecurse": "4.2.0",
-        "estraverse": "4.2.0"
+        "es6-map": "^0.1.3",
+        "es6-weak-map": "^2.0.1",
+        "esrecurse": "^4.1.0",
+        "estraverse": "^4.1.1"
       }
     },
     "eslint": {
@@ -941,84 +897,83 @@
       "integrity": "sha1-v7OO/Lf5mBiApyS8LmHSFAku46k=",
       "dev": true,
       "requires": {
-        "chalk": "1.1.3",
-        "concat-stream": "1.6.0",
-        "debug": "2.6.9",
-        "doctrine": "1.5.0",
-        "es6-map": "0.1.5",
-        "escope": "3.6.0",
-        "espree": "3.5.1",
-        "estraverse": "4.2.0",
-        "esutils": "2.0.2",
-        "file-entry-cache": "1.3.1",
-        "glob": "6.0.4",
-        "globals": "8.18.0",
-        "ignore": "2.2.19",
-        "inquirer": "0.12.0",
-        "is-my-json-valid": "2.16.1",
-        "is-resolvable": "1.0.0",
-        "js-yaml": "3.10.0",
-        "json-stable-stringify": "1.0.1",
-        "lodash": "4.17.10",
-        "mkdirp": "0.5.1",
-        "optionator": "0.8.2",
-        "path-is-absolute": "1.0.1",
-        "path-is-inside": "1.0.2",
-        "pluralize": "1.2.1",
-        "progress": "1.1.8",
-        "require-uncached": "1.0.3",
-        "resolve": "1.4.0",
-        "shelljs": "0.5.3",
-        "strip-json-comments": "1.0.4",
-        "table": "3.8.3",
-        "text-table": "0.2.0",
-        "user-home": "2.0.0"
+        "chalk": "^1.0.0",
+        "concat-stream": "^1.4.6",
+        "debug": "^2.1.1",
+        "doctrine": "^1.2.0",
+        "es6-map": "^0.1.3",
+        "escope": "^3.6.0",
+        "espree": "^3.1.1",
+        "estraverse": "^4.2.0",
+        "esutils": "^2.0.2",
+        "file-entry-cache": "^1.1.1",
+        "glob": "^6.0.4",
+        "globals": "^8.18.0",
+        "ignore": "^2.2.19",
+        "inquirer": "^0.12.0",
+        "is-my-json-valid": "^2.10.0",
+        "is-resolvable": "^1.0.0",
+        "js-yaml": "^3.5.1",
+        "json-stable-stringify": "^1.0.0",
+        "lodash": "^4.0.0",
+        "mkdirp": "^0.5.0",
+        "optionator": "^0.8.1",
+        "path-is-absolute": "^1.0.0",
+        "path-is-inside": "^1.0.1",
+        "pluralize": "^1.2.1",
+        "progress": "^1.1.8",
+        "require-uncached": "^1.0.2",
+        "resolve": "^1.1.6",
+        "shelljs": "^0.5.3",
+        "strip-json-comments": "~1.0.1",
+        "table": "^3.7.8",
+        "text-table": "~0.2.0",
+        "user-home": "^2.0.0"
       }
     },
     "espree": {
-      "version": "3.5.1",
-      "resolved": "https://registry.npmjs.org/espree/-/espree-3.5.1.tgz",
-      "integrity": "sha1-DJiLirRttTEAoZVK5LqZXd0n2H4=",
+      "version": "3.5.4",
+      "resolved": "https://registry.npmjs.org/espree/-/espree-3.5.4.tgz",
+      "integrity": "sha512-yAcIQxtmMiB/jL32dzEp2enBeidsB7xWPLNiw3IIkpVds1P+h7qF9YwJq1yUNzp2OKXgAprs4F61ih66UsoD1A==",
       "dev": true,
       "requires": {
-        "acorn": "5.1.2",
-        "acorn-jsx": "3.0.1"
+        "acorn": "^5.5.0",
+        "acorn-jsx": "^3.0.0"
       }
     },
     "esprima": {
       "version": "https://github.com/ariya/esprima/archive/85fc2f4b6ad109a86d80d9821f52b5b38d0105c0.tar.gz",
-      "integrity": "sha1-toewHi8U14sGe4o8gEfmmHLXdow=",
+      "integrity": "sha512-GyWe6YkK295gEHgCUfRdjb9BWkxWrf3zAB6AvUGhSmW4HLCOw0Zq6cY3eSKCQQk6kaimdNQFssPUY5t8cz2SdQ==",
       "dev": true
     },
     "espurify": {
-      "version": "1.7.0",
-      "resolved": "https://registry.npmjs.org/espurify/-/espurify-1.7.0.tgz",
-      "integrity": "sha1-HFz2y8zDLm9jk4C9T5kfq5up0iY=",
+      "version": "1.8.1",
+      "resolved": "https://registry.npmjs.org/espurify/-/espurify-1.8.1.tgz",
+      "integrity": "sha512-ZDko6eY/o+D/gHCWyHTU85mKDgYcS4FJj7S+YD6WIInm7GQ6AnOjmcL4+buFV/JOztVLELi/7MmuGU5NHta0Mg==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1"
+        "core-js": "^2.0.0"
       }
     },
     "esrecurse": {
-      "version": "4.2.0",
-      "resolved": "https://registry.npmjs.org/esrecurse/-/esrecurse-4.2.0.tgz",
-      "integrity": "sha1-+pVo2Y04I/mkHZHpAtyrnqblsWM=",
+      "version": "4.2.1",
+      "resolved": "https://registry.npmjs.org/esrecurse/-/esrecurse-4.2.1.tgz",
+      "integrity": "sha512-64RBB++fIOAXPw3P9cy89qfMlvZEXZkqqJkjqqXIvzP5ezRZjW+lPWjw35UX/3EhUPFYbg5ER4JYgDw4007/DQ==",
       "dev": true,
       "requires": {
-        "estraverse": "4.2.0",
-        "object-assign": "4.1.1"
+        "estraverse": "^4.1.0"
       }
     },
     "estraverse": {
-      "version": "4.2.0",
-      "resolved": "https://registry.npmjs.org/estraverse/-/estraverse-4.2.0.tgz",
-      "integrity": "sha1-De4/7TH81GlhjOc0IJn8GvoL2xM=",
+      "version": "4.3.0",
+      "resolved": "https://registry.npmjs.org/estraverse/-/estraverse-4.3.0.tgz",
+      "integrity": "sha512-39nnKffWz8xN1BU/2c79n9nB9HDzo0niYUqx6xyqUnyoAnQyyWpOTdZEeiCch8BBu515t4wp9ZmgVfVhn9EBpw==",
       "dev": true
     },
     "esutils": {
-      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/esutils/-/esutils-2.0.2.tgz",
-      "integrity": "sha1-Cr9PHKpbyx96nYrMbepPqqBLrJs=",
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/esutils/-/esutils-2.0.3.tgz",
+      "integrity": "sha512-kVscqXk4OCp68SZ0dkgEKVi6/8ij300KBWTJq32P/dYeWTSwK41WyTxalN1eRmA5Z9UU/LX9D7FWSmV9SAYx6g==",
       "dev": true
     },
     "etag": {
@@ -1033,8 +988,8 @@
       "integrity": "sha1-34xp7vFkeSPHFXuc6DhAYQsCzDk=",
       "dev": true,
       "requires": {
-        "d": "1.0.0",
-        "es5-ext": "0.10.30"
+        "d": "1",
+        "es5-ext": "~0.10.14"
       }
     },
     "exit-hook": {
@@ -1044,41 +999,58 @@
       "dev": true
     },
     "express": {
-      "version": "4.16.1",
-      "resolved": "https://registry.npmjs.org/express/-/express-4.16.1.tgz",
-      "integrity": "sha512-STB7LZ4N0L+81FJHGla2oboUHTk4PaN1RsOkoRh9OSeEKylvF5hwKYVX1xCLFaCT7MD0BNG/gX2WFMLqY6EMBw==",
+      "version": "4.17.1",
+      "resolved": "https://registry.npmjs.org/express/-/express-4.17.1.tgz",
+      "integrity": "sha512-mHJ9O79RqluphRrcw2X/GTh3k9tVv8YcoyY4Kkh4WDMUYKRZUq0h1o0w2rrrxBqM7VoeUVqgb27xlEMXTnYt4g==",
       "dev": true,
       "requires": {
-        "accepts": "1.3.4",
+        "accepts": "~1.3.7",
         "array-flatten": "1.1.1",
-        "body-parser": "1.18.2",
-        "content-disposition": "0.5.2",
-        "content-type": "1.0.4",
-        "cookie": "0.3.1",
+        "body-parser": "1.19.0",
+        "content-disposition": "0.5.3",
+        "content-type": "~1.0.4",
+        "cookie": "0.4.0",
         "cookie-signature": "1.0.6",
         "debug": "2.6.9",
-        "depd": "1.1.1",
-        "encodeurl": "1.0.1",
-        "escape-html": "1.0.3",
-        "etag": "1.8.1",
-        "finalhandler": "1.1.0",
+        "depd": "~1.1.2",
+        "encodeurl": "~1.0.2",
+        "escape-html": "~1.0.3",
+        "etag": "~1.8.1",
+        "finalhandler": "~1.1.2",
         "fresh": "0.5.2",
         "merge-descriptors": "1.0.1",
-        "methods": "1.1.2",
-        "on-finished": "2.3.0",
-        "parseurl": "1.3.2",
+        "methods": "~1.1.2",
+        "on-finished": "~2.3.0",
+        "parseurl": "~1.3.3",
         "path-to-regexp": "0.1.7",
-        "proxy-addr": "2.0.2",
-        "qs": "6.5.1",
-        "range-parser": "1.2.0",
-        "safe-buffer": "5.1.1",
-        "send": "0.16.1",
-        "serve-static": "1.13.1",
-        "setprototypeof": "1.1.0",
-        "statuses": "1.3.1",
-        "type-is": "1.6.15",
+        "proxy-addr": "~2.0.5",
+        "qs": "6.7.0",
+        "range-parser": "~1.2.1",
+        "safe-buffer": "5.1.2",
+        "send": "0.17.1",
+        "serve-static": "1.14.1",
+        "setprototypeof": "1.1.1",
+        "statuses": "~1.5.0",
+        "type-is": "~1.6.18",
         "utils-merge": "1.0.1",
-        "vary": "1.1.2"
+        "vary": "~1.1.2"
+      }
+    },
+    "ext": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/ext/-/ext-1.4.0.tgz",
+      "integrity": "sha512-Key5NIsUxdqKg3vIsdw9dSuXpPCQ297y6wBjL30edxwPgt2E44WcWBZey/ZvUc6sERLTxKdyCu4gZFmUbk1Q7A==",
+      "dev": true,
+      "requires": {
+        "type": "^2.0.0"
+      },
+      "dependencies": {
+        "type": {
+          "version": "2.0.0",
+          "resolved": "https://registry.npmjs.org/type/-/type-2.0.0.tgz",
+          "integrity": "sha512-KBt58xCHry4Cejnc2ISQAF7QY+ORngsWfxezO68+12hKV6lQY8P/psIkcbjeHWn7MqcgciWJyCCevFMJdIXpow==",
+          "dev": true
+        }
       }
     },
     "fast-levenshtein": {
@@ -1093,8 +1065,8 @@
       "integrity": "sha1-y+Hjr/zxzUS4DK3+0o3Hk6lwHS4=",
       "dev": true,
       "requires": {
-        "escape-string-regexp": "1.0.5",
-        "object-assign": "4.1.1"
+        "escape-string-regexp": "^1.0.5",
+        "object-assign": "^4.1.0"
       }
     },
     "file-entry-cache": {
@@ -1103,8 +1075,8 @@
       "integrity": "sha1-RMYepgeuS+nBQC9B9EJwy/4zT/g=",
       "dev": true,
       "requires": {
-        "flat-cache": "1.3.0",
-        "object-assign": "4.1.1"
+        "flat-cache": "^1.2.1",
+        "object-assign": "^4.0.1"
       }
     },
     "fileset": {
@@ -1113,8 +1085,8 @@
       "integrity": "sha1-WI74lzxmI7KnbfRlEFaWuWqsgGc=",
       "dev": true,
       "requires": {
-        "glob": "5.0.15",
-        "minimatch": "2.0.10"
+        "glob": "5.x",
+        "minimatch": "2.x"
       },
       "dependencies": {
         "glob": {
@@ -1123,11 +1095,11 @@
           "integrity": "sha1-G8k2ueAvSmA/zCIuz3Yz0wuLk7E=",
           "dev": true,
           "requires": {
-            "inflight": "1.0.6",
-            "inherits": "2.0.3",
-            "minimatch": "2.0.10",
-            "once": "1.4.0",
-            "path-is-absolute": "1.0.1"
+            "inflight": "^1.0.4",
+            "inherits": "2",
+            "minimatch": "2 || 3",
+            "once": "^1.3.0",
+            "path-is-absolute": "^1.0.0"
           }
         },
         "minimatch": {
@@ -1136,44 +1108,38 @@
           "integrity": "sha1-jQh8OcazjAAbl/ynzm0OHoCvusc=",
           "dev": true,
           "requires": {
-            "brace-expansion": "1.1.8"
+            "brace-expansion": "^1.0.0"
           }
         }
       }
     },
     "finalhandler": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/finalhandler/-/finalhandler-1.1.0.tgz",
-      "integrity": "sha1-zgtoVbRYU+eRsvzGgARtiCU91/U=",
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/finalhandler/-/finalhandler-1.1.2.tgz",
+      "integrity": "sha512-aAWcW57uxVNrQZqFXjITpW3sIUQmHGG3qSb9mUah9MgMC4NeWhNOlNjXEYq3HjRAvL6arUviZGGJsBg6z0zsWA==",
       "dev": true,
       "requires": {
         "debug": "2.6.9",
-        "encodeurl": "1.0.1",
-        "escape-html": "1.0.3",
-        "on-finished": "2.3.0",
-        "parseurl": "1.3.2",
-        "statuses": "1.3.1",
-        "unpipe": "1.0.0"
+        "encodeurl": "~1.0.2",
+        "escape-html": "~1.0.3",
+        "on-finished": "~2.3.0",
+        "parseurl": "~1.3.3",
+        "statuses": "~1.5.0",
+        "unpipe": "~1.0.0"
       }
     },
     "flat-cache": {
-      "version": "1.3.0",
-      "resolved": "https://registry.npmjs.org/flat-cache/-/flat-cache-1.3.0.tgz",
-      "integrity": "sha1-0wMLMrOBVPTjt+nHCfSQ9++XxIE=",
+      "version": "1.3.4",
+      "resolved": "https://registry.npmjs.org/flat-cache/-/flat-cache-1.3.4.tgz",
+      "integrity": "sha512-VwyB3Lkgacfik2vhqR4uv2rvebqmDvFu4jlN/C1RzWoJEo8I7z4Q404oiqYCkq41mni8EzQnm95emU9seckwtg==",
       "dev": true,
       "requires": {
-        "circular-json": "0.3.3",
-        "del": "2.2.2",
-        "graceful-fs": "4.1.11",
-        "write": "0.2.1"
+        "circular-json": "^0.3.1",
+        "graceful-fs": "^4.1.2",
+        "rimraf": "~2.6.2",
+        "write": "^0.2.1"
       }
     },
-    "foreach": {
-      "version": "2.0.5",
-      "resolved": "https://registry.npmjs.org/foreach/-/foreach-2.0.5.tgz",
-      "integrity": "sha1-C+4AUBiusmDQo6865ljdATbsG5k=",
-      "dev": true
-    },
     "forwarded": {
       "version": "0.1.2",
       "resolved": "https://registry.npmjs.org/forwarded/-/forwarded-0.1.2.tgz",
@@ -1193,64 +1159,22 @@
       "dev": true
     },
     "gaze": {
-      "version": "0.3.4",
-      "resolved": "https://registry.npmjs.org/gaze/-/gaze-0.3.4.tgz",
-      "integrity": "sha1-X5S92gr+U7xxCWm81vKCVI1gwnk=",
+      "version": "1.1.3",
+      "resolved": "https://registry.npmjs.org/gaze/-/gaze-1.1.3.tgz",
+      "integrity": "sha512-BRdNm8hbWzFzWHERTrejLqwHDfS4GibPoq5wjTPIoJHoBtKGPg3xAFfxmM+9ztbXelxcf2hwQcaz1PtmFeue8g==",
       "dev": true,
       "requires": {
-        "fileset": "0.1.8",
-        "minimatch": "0.2.14"
-      },
-      "dependencies": {
-        "fileset": {
-          "version": "0.1.8",
-          "resolved": "https://registry.npmjs.org/fileset/-/fileset-0.1.8.tgz",
-          "integrity": "sha1-UGuRqTluqn4y+0KoQHfHoMc2t0E=",
-          "dev": true,
-          "requires": {
-            "glob": "3.2.11",
-            "minimatch": "0.2.14"
-          }
-        },
-        "glob": {
-          "version": "3.2.11",
-          "resolved": "https://registry.npmjs.org/glob/-/glob-3.2.11.tgz",
-          "integrity": "sha1-Spc/Y1uRkPcV0QmH1cAP0oFevj0=",
-          "dev": true,
-          "requires": {
-            "inherits": "2.0.3",
-            "minimatch": "0.3.0"
-          },
-          "dependencies": {
-            "minimatch": {
-              "version": "0.3.0",
-              "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-0.3.0.tgz",
-              "integrity": "sha1-J12O2qxPG7MyZHIInnlJyDlGmd0=",
-              "dev": true,
-              "requires": {
-                "lru-cache": "2.7.3",
-                "sigmund": "1.0.1"
-              }
-            }
-          }
-        },
-        "minimatch": {
-          "version": "0.2.14",
-          "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-0.2.14.tgz",
-          "integrity": "sha1-x054BXT2PG+aCQ6Q775u9TpqdWo=",
-          "dev": true,
-          "requires": {
-            "lru-cache": "2.7.3",
-            "sigmund": "1.0.1"
-          }
-        }
+        "globule": "^1.0.0"
       }
     },
     "generate-function": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/generate-function/-/generate-function-2.0.0.tgz",
-      "integrity": "sha1-aFj+fAlpt9TpCTM3ZHrHn2DfvnQ=",
-      "dev": true
+      "version": "2.3.1",
+      "resolved": "https://registry.npmjs.org/generate-function/-/generate-function-2.3.1.tgz",
+      "integrity": "sha512-eeB5GfMNeevm/GRYq20ShmsaGcmI81kIX2K9XQx5miC8KdHaC6Jm0qQ8ZNeGOi7wYB8OsdxKs+Y2oVuTFuVwKQ==",
+      "dev": true,
+      "requires": {
+        "is-property": "^1.0.2"
+      }
     },
     "generate-object-property": {
       "version": "1.2.0",
@@ -1258,7 +1182,7 @@
       "integrity": "sha1-nA4cQDCM6AT0eDYYuTf6iPmdUNA=",
       "dev": true,
       "requires": {
-        "is-property": "1.0.2"
+        "is-property": "^1.0.0"
       }
     },
     "github-flavored-markdown": {
@@ -1273,11 +1197,11 @@
       "integrity": "sha1-DwiGD2oVUSey+t1PnOJLGqtuTSI=",
       "dev": true,
       "requires": {
-        "inflight": "1.0.6",
-        "inherits": "2.0.3",
-        "minimatch": "3.0.4",
-        "once": "1.4.0",
-        "path-is-absolute": "1.0.1"
+        "inflight": "^1.0.4",
+        "inherits": "2",
+        "minimatch": "2 || 3",
+        "once": "^1.3.0",
+        "path-is-absolute": "^1.0.0"
       }
     },
     "globals": {
@@ -1286,40 +1210,37 @@
       "integrity": "sha1-k9SmK9ysOM+vr8R9awNHaMsP/LQ=",
       "dev": true
     },
-    "globby": {
-      "version": "5.0.0",
-      "resolved": "https://registry.npmjs.org/globby/-/globby-5.0.0.tgz",
-      "integrity": "sha1-69hGZ8oNuzMLmbz8aOrCvFQ3Dg0=",
+    "globule": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/globule/-/globule-1.3.0.tgz",
+      "integrity": "sha512-YlD4kdMqRCQHrhVdonet4TdRtv1/sZKepvoxNT4Nrhrp5HI8XFfc8kFlGlBn2myBo80aGp8Eft259mbcUJhgSg==",
       "dev": true,
       "requires": {
-        "array-union": "1.0.2",
-        "arrify": "1.0.1",
-        "glob": "7.1.2",
-        "object-assign": "4.1.1",
-        "pify": "2.3.0",
-        "pinkie-promise": "2.0.1"
+        "glob": "~7.1.1",
+        "lodash": "~4.17.10",
+        "minimatch": "~3.0.2"
       },
       "dependencies": {
         "glob": {
-          "version": "7.1.2",
-          "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.2.tgz",
-          "integrity": "sha512-MJTUg1kjuLeQCJ+ccE4Vpa6kKVXkPYJ2mOCQyUuKLcLQsdrMCpBPUi8qVE6+YuaJkozeA9NusTAw3hLr8Xe5EQ==",
+          "version": "7.1.6",
+          "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.6.tgz",
+          "integrity": "sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==",
           "dev": true,
           "requires": {
-            "fs.realpath": "1.0.0",
-            "inflight": "1.0.6",
-            "inherits": "2.0.3",
-            "minimatch": "3.0.4",
-            "once": "1.4.0",
-            "path-is-absolute": "1.0.1"
+            "fs.realpath": "^1.0.0",
+            "inflight": "^1.0.4",
+            "inherits": "2",
+            "minimatch": "^3.0.4",
+            "once": "^1.3.0",
+            "path-is-absolute": "^1.0.0"
           }
         }
       }
     },
     "graceful-fs": {
-      "version": "4.1.11",
-      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.1.11.tgz",
-      "integrity": "sha1-Dovf5NHduIVNZOBOp8AOKgJuVlg=",
+      "version": "4.2.3",
+      "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.3.tgz",
+      "integrity": "sha512-a30VEBm4PEdx1dRB7MFK7BejejvCvBronbLjht+sHuGYj8PHs7M/5Z+rt5lw551vZ7yfTCj4Vuyy3mSJytDWRQ==",
       "dev": true
     },
     "graceful-readlink": {
@@ -1335,30 +1256,39 @@
       "dev": true
     },
     "handlebars": {
-      "version": "4.0.10",
-      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.0.10.tgz",
-      "integrity": "sha1-PTDHGLCaPZbyPqTMH0A8TTup/08=",
+      "version": "4.5.3",
+      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.5.3.tgz",
+      "integrity": "sha512-3yPecJoJHK/4c6aZhSvxOyG4vJKDshV36VHp0iVCDVh7o9w2vwi3NSnL2MMPj3YdduqaBcu7cGbggJQM0br9xA==",
       "dev": true,
       "requires": {
-        "async": "1.5.2",
-        "optimist": "0.6.1",
-        "source-map": "0.4.4",
-        "uglify-js": "2.7.0"
+        "neo-async": "^2.6.0",
+        "optimist": "^0.6.1",
+        "source-map": "^0.6.1",
+        "uglify-js": "^3.1.4"
       },
       "dependencies": {
-        "async": {
-          "version": "1.5.2",
-          "resolved": "https://registry.npmjs.org/async/-/async-1.5.2.tgz",
-          "integrity": "sha1-7GphrlZIDAw8skHJVhjiCJL5Zyo=",
-          "dev": true
+        "commander": {
+          "version": "2.20.3",
+          "resolved": "https://registry.npmjs.org/commander/-/commander-2.20.3.tgz",
+          "integrity": "sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==",
+          "dev": true,
+          "optional": true
         },
         "source-map": {
-          "version": "0.4.4",
-          "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.4.4.tgz",
-          "integrity": "sha1-66T12pwNyZneaAMti092FzZSA2s=",
+          "version": "0.6.1",
+          "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz",
+          "integrity": "sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==",
+          "dev": true
+        },
+        "uglify-js": {
+          "version": "3.7.4",
+          "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.7.4.tgz",
+          "integrity": "sha512-tinYWE8X1QfCHxS1lBS8yiDekyhSXOO6R66yNOCdUJeojxxw+PX2BHAz/BWyW7PQ7pkiWVxJfIEbiDxyLWvUGg==",
           "dev": true,
+          "optional": true,
           "requires": {
-            "amdefine": "1.0.1"
+            "commander": "~2.20.3",
+            "source-map": "~0.6.1"
           }
         }
       }
@@ -1369,7 +1299,7 @@
       "integrity": "sha1-NPUEnOHs3ysGSa8+8k5F7TVBbZE=",
       "dev": true,
       "requires": {
-        "ansi-regex": "2.1.1"
+        "ansi-regex": "^2.0.0"
       }
     },
     "has-flag": {
@@ -1390,8 +1320,8 @@
       "integrity": "sha1-42w/LSyufXRqhX440Y1fMqeILbg=",
       "dev": true,
       "requires": {
-        "os-homedir": "1.0.2",
-        "os-tmpdir": "1.0.2"
+        "os-homedir": "^1.0.0",
+        "os-tmpdir": "^1.0.1"
       }
     },
     "hooks-fixed": {
@@ -1400,30 +1330,34 @@
       "integrity": "sha512-YurCM4gQSetcrhwEtpQHhQ4M7Zo7poNGqY4kQGeBS6eZtOcT3tnNs01ThFa0jYBByAiYt1MjMjP/YApG0EnAvQ=="
     },
     "http-errors": {
-      "version": "1.6.2",
-      "resolved": "https://registry.npmjs.org/http-errors/-/http-errors-1.6.2.tgz",
-      "integrity": "sha1-CgAsyFcHGSp+eUbO7cERVfYOxzY=",
+      "version": "1.7.2",
+      "resolved": "https://registry.npmjs.org/http-errors/-/http-errors-1.7.2.tgz",
+      "integrity": "sha512-uUQBt3H/cSIVfch6i1EuPNy/YsRSOUBXTVfZ+yR7Zjez3qjBz6i9+i4zjNaoqcoFVI4lQJ5plg63TvGfRSDCRg==",
       "dev": true,
       "requires": {
-        "depd": "1.1.1",
+        "depd": "~1.1.2",
         "inherits": "2.0.3",
-        "setprototypeof": "1.0.3",
-        "statuses": "1.3.1"
+        "setprototypeof": "1.1.1",
+        "statuses": ">= 1.5.0 < 2",
+        "toidentifier": "1.0.0"
       },
       "dependencies": {
-        "setprototypeof": {
-          "version": "1.0.3",
-          "resolved": "https://registry.npmjs.org/setprototypeof/-/setprototypeof-1.0.3.tgz",
-          "integrity": "sha1-ZlZ+NwQ+608E2RvWWMDL77VbjgQ=",
+        "inherits": {
+          "version": "2.0.3",
+          "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
+          "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=",
           "dev": true
         }
       }
     },
     "iconv-lite": {
-      "version": "0.4.19",
-      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.19.tgz",
-      "integrity": "sha512-oTZqweIP51xaGPI4uPa56/Pri/480R+mo7SeU+YETByQNhDG55ycFyNLIgta9vXhILrxXDmF7ZGhqZIcuN0gJQ==",
-      "dev": true
+      "version": "0.4.24",
+      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.24.tgz",
+      "integrity": "sha512-v3MXnZAcvnywkTUEZomIActle7RXXeedOR31wwl7VlyoXO4Qi9arvSenNQWne1TcRwhCL1HwLI21bEqdpj8/rA==",
+      "dev": true,
+      "requires": {
+        "safer-buffer": ">= 2.1.2 < 3"
+      }
     },
     "ignore": {
       "version": "2.2.19",
@@ -1443,14 +1377,14 @@
       "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
       "dev": true,
       "requires": {
-        "once": "1.4.0",
-        "wrappy": "1.0.2"
+        "once": "^1.3.0",
+        "wrappy": "1"
       }
     },
     "inherits": {
-      "version": "2.0.3",
-      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
-      "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4="
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+      "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ=="
     },
     "inquirer": {
       "version": "0.12.0",
@@ -1458,40 +1392,40 @@
       "integrity": "sha1-HvK/1jUE3wvHV4X/+MLEHfEvB34=",
       "dev": true,
       "requires": {
-        "ansi-escapes": "1.4.0",
-        "ansi-regex": "2.1.1",
-        "chalk": "1.1.3",
-        "cli-cursor": "1.0.2",
-        "cli-width": "2.2.0",
-        "figures": "1.7.0",
-        "lodash": "4.17.10",
-        "readline2": "1.0.1",
-        "run-async": "0.1.0",
-        "rx-lite": "3.1.2",
-        "string-width": "1.0.2",
-        "strip-ansi": "3.0.1",
-        "through": "2.3.8"
+        "ansi-escapes": "^1.1.0",
+        "ansi-regex": "^2.0.0",
+        "chalk": "^1.0.0",
+        "cli-cursor": "^1.0.1",
+        "cli-width": "^2.0.0",
+        "figures": "^1.3.5",
+        "lodash": "^4.3.0",
+        "readline2": "^1.0.1",
+        "run-async": "^0.1.0",
+        "rx-lite": "^3.1.2",
+        "string-width": "^1.0.1",
+        "strip-ansi": "^3.0.0",
+        "through": "^2.3.6"
       }
     },
     "invariant": {
-      "version": "2.2.2",
-      "resolved": "https://registry.npmjs.org/invariant/-/invariant-2.2.2.tgz",
-      "integrity": "sha1-nh9WrArNtr8wMwbzOL47IErmA2A=",
+      "version": "2.2.4",
+      "resolved": "https://registry.npmjs.org/invariant/-/invariant-2.2.4.tgz",
+      "integrity": "sha512-phJfQVBuaJM5raOpJjSfkiD6BpbCE4Ns//LaXl6wGYtUBY83nWS6Rf9tXm2e8VaK60JEjYldbPif/A2B1C2gNA==",
       "dev": true,
       "requires": {
-        "loose-envify": "1.3.1"
+        "loose-envify": "^1.0.0"
       }
     },
     "ipaddr.js": {
-      "version": "1.5.2",
-      "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.5.2.tgz",
-      "integrity": "sha1-1LUFvemUaYfM8PxY2QEP+WB+P6A=",
+      "version": "1.9.0",
+      "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.9.0.tgz",
+      "integrity": "sha512-M4Sjn6N/+O6/IXSJseKqHoFc+5FdGJ22sXqnjTpdZweHK64MzEPAyQZyEU3R/KRv2GLoa7nNtg/C2Ev6m7z+eA==",
       "dev": true
     },
     "is-buffer": {
-      "version": "1.1.5",
-      "resolved": "https://registry.npmjs.org/is-buffer/-/is-buffer-1.1.5.tgz",
-      "integrity": "sha1-Hzsm72E7IUuIy8ojzGwB2Hlh7sw=",
+      "version": "1.1.6",
+      "resolved": "https://registry.npmjs.org/is-buffer/-/is-buffer-1.1.6.tgz",
+      "integrity": "sha512-NcdALwpXkTm5Zvvbk7owOUSvVvBKDgKP5/ewfXEznmQFfs4ZRmanOeKBTjRVjka3QFoN6XJ+9F3USqfHqTaU5w==",
       "dev": true
     },
     "is-finite": {
@@ -1500,7 +1434,7 @@
       "integrity": "sha1-zGZ3aVYCvlUO8R6LSqYwU0K20Ko=",
       "dev": true,
       "requires": {
-        "number-is-nan": "1.0.1"
+        "number-is-nan": "^1.0.0"
       }
     },
     "is-fullwidth-code-point": {
@@ -1509,43 +1443,26 @@
       "integrity": "sha1-754xOG8DGn8NZDr4L95QxFfvAMs=",
       "dev": true,
       "requires": {
-        "number-is-nan": "1.0.1"
+        "number-is-nan": "^1.0.0"
       }
     },
-    "is-my-json-valid": {
-      "version": "2.16.1",
-      "resolved": "https://registry.npmjs.org/is-my-json-valid/-/is-my-json-valid-2.16.1.tgz",
-      "integrity": "sha512-ochPsqWS1WXj8ZnMIV0vnNXooaMhp7cyL4FMSIPKTtnV0Ha/T19G2b9kkhcNsabV9bxYkze7/aLZJb/bYuFduQ==",
-      "dev": true,
-      "requires": {
-        "generate-function": "2.0.0",
-        "generate-object-property": "1.2.0",
-        "jsonpointer": "4.0.1",
-        "xtend": "4.0.1"
-      }
-    },
-    "is-path-cwd": {
+    "is-my-ip-valid": {
       "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/is-path-cwd/-/is-path-cwd-1.0.0.tgz",
-      "integrity": "sha1-0iXsIxMuie3Tj9p2dHLmLmXxEG0=",
+      "resolved": "https://registry.npmjs.org/is-my-ip-valid/-/is-my-ip-valid-1.0.0.tgz",
+      "integrity": "sha512-gmh/eWXROncUzRnIa1Ubrt5b8ep/MGSnfAUI3aRp+sqTCs1tv1Isl8d8F6JmkN3dXKc3ehZMrtiPN9eL03NuaQ==",
       "dev": true
     },
-    "is-path-in-cwd": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/is-path-in-cwd/-/is-path-in-cwd-1.0.0.tgz",
-      "integrity": "sha1-ZHdYK4IU1gI0YJRWcAO+ip6sBNw=",
-      "dev": true,
-      "requires": {
-        "is-path-inside": "1.0.0"
-      }
-    },
-    "is-path-inside": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/is-path-inside/-/is-path-inside-1.0.0.tgz",
-      "integrity": "sha1-/AbloWg/vaE95mev9xe7wQpI838=",
+    "is-my-json-valid": {
+      "version": "2.20.0",
+      "resolved": "https://registry.npmjs.org/is-my-json-valid/-/is-my-json-valid-2.20.0.tgz",
+      "integrity": "sha512-XTHBZSIIxNsIsZXg7XB5l8z/OBFosl1Wao4tXLpeC7eKU4Vm/kdop2azkPqULwnfGQjmeDIyey9g7afMMtdWAA==",
       "dev": true,
       "requires": {
-        "path-is-inside": "1.0.2"
+        "generate-function": "^2.0.0",
+        "generate-object-property": "^1.1.0",
+        "is-my-ip-valid": "^1.0.0",
+        "jsonpointer": "^4.0.0",
+        "xtend": "^4.0.0"
       }
     },
     "is-property": {
@@ -1555,13 +1472,10 @@
       "dev": true
     },
     "is-resolvable": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/is-resolvable/-/is-resolvable-1.0.0.tgz",
-      "integrity": "sha1-jfV8YeouPFAUCNEA+wE8+NbgzGI=",
-      "dev": true,
-      "requires": {
-        "tryit": "1.0.3"
-      }
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/is-resolvable/-/is-resolvable-1.1.0.tgz",
+      "integrity": "sha512-qgDYXFSR5WvEfuS5dMj6oTMEbrrSaM0CrFk2Yiq/gXnBvD9pMa2jGXxyhGLfvhZpuMZe18CJpFxAt3CRs42NMg==",
+      "dev": true
     },
     "isarray": {
       "version": "1.0.0",
@@ -1580,20 +1494,20 @@
       "integrity": "sha1-6M9xjf7bcTyDNKuf+t418QQtKlY=",
       "dev": true,
       "requires": {
-        "abbrev": "1.0.9",
-        "async": "1.5.2",
-        "escodegen": "1.8.1",
-        "esprima": "2.7.3",
-        "fileset": "0.2.1",
-        "handlebars": "4.0.10",
-        "js-yaml": "3.10.0",
-        "mkdirp": "0.5.1",
-        "nopt": "3.0.6",
-        "once": "1.4.0",
-        "resolve": "1.1.7",
-        "supports-color": "3.2.3",
-        "which": "1.3.0",
-        "wordwrap": "1.0.0"
+        "abbrev": "1.0.x",
+        "async": "1.x",
+        "escodegen": "1.8.x",
+        "esprima": "2.7.x",
+        "fileset": "0.2.x",
+        "handlebars": "^4.0.1",
+        "js-yaml": "3.x",
+        "mkdirp": "0.5.x",
+        "nopt": "3.x",
+        "once": "1.x",
+        "resolve": "1.1.x",
+        "supports-color": "^3.1.0",
+        "which": "^1.1.1",
+        "wordwrap": "^1.0.0"
       },
       "dependencies": {
         "async": {
@@ -1620,7 +1534,7 @@
           "integrity": "sha1-ZawFBLOVQXHYpklGsq48u4pfVPY=",
           "dev": true,
           "requires": {
-            "has-flag": "1.0.0"
+            "has-flag": "^1.0.0"
           }
         }
       }
@@ -1650,36 +1564,36 @@
       }
     },
     "jasmine-growl-reporter": {
-      "version": "0.0.3",
-      "resolved": "https://registry.npmjs.org/jasmine-growl-reporter/-/jasmine-growl-reporter-0.0.3.tgz",
-      "integrity": "sha1-uHrlUeNZ0orVIXdl6u9sB7dj9sg=",
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/jasmine-growl-reporter/-/jasmine-growl-reporter-2.0.0.tgz",
+      "integrity": "sha512-RYwVfPaGgxQQSHDOt6jQ99/KAkFQ/Fiwg/AzBS+uO9A4UhGhxb7hwXaUUSU/Zs0MxBoFNqmIRC+7P4/+5O3lXg==",
       "dev": true,
       "requires": {
-        "growl": "1.7.0"
+        "growl": "^1.10.5"
       },
       "dependencies": {
         "growl": {
-          "version": "1.7.0",
-          "resolved": "https://registry.npmjs.org/growl/-/growl-1.7.0.tgz",
-          "integrity": "sha1-3i1mE20ALhErpw8/EMMc98NQsto=",
+          "version": "1.10.5",
+          "resolved": "https://registry.npmjs.org/growl/-/growl-1.10.5.tgz",
+          "integrity": "sha512-qBr4OuELkhPenW6goKVXiv47US3clb3/IbuWF9KNKEijAy9oeHxU9IgzjvJhHkUzhaj7rOUD7+YGWqUjLp5oSA==",
           "dev": true
         }
       }
     },
     "jasmine-node": {
-      "version": "1.14.5",
-      "resolved": "https://registry.npmjs.org/jasmine-node/-/jasmine-node-1.14.5.tgz",
-      "integrity": "sha1-GOg5e4VpJO53ADZmw3MbWupQw50=",
-      "dev": true,
-      "requires": {
-        "coffee-script": "1.12.7",
-        "gaze": "0.3.4",
-        "jasmine-growl-reporter": "0.0.3",
-        "jasmine-reporters": "1.0.2",
-        "mkdirp": "0.3.5",
-        "requirejs": "2.3.5",
-        "underscore": "1.5.2",
-        "walkdir": "0.0.12"
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/jasmine-node/-/jasmine-node-3.0.0.tgz",
+      "integrity": "sha512-vUa5Q7bQYwHHqi6FlJYndiKqZp+d+c3MKe0QUMwwrC4JRmoRV3zkg0buxB/uQ6qLh0NO34TNstpAnvaZ6xGlAA==",
+      "dev": true,
+      "requires": {
+        "coffeescript": "~1.12.7",
+        "gaze": "~1.1.2",
+        "jasmine-growl-reporter": "~2.0.0",
+        "jasmine-reporters": "~1.0.0",
+        "mkdirp": "~0.3.5",
+        "requirejs": "~2.3.6",
+        "underscore": "~1.9.1",
+        "walkdir": "~0.0.12"
       },
       "dependencies": {
         "mkdirp": {
@@ -1687,6 +1601,12 @@
           "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-0.3.5.tgz",
           "integrity": "sha1-3j5fiWHIjHh+4TaN+EmsRBPsqNc=",
           "dev": true
+        },
+        "underscore": {
+          "version": "1.9.2",
+          "resolved": "https://registry.npmjs.org/underscore/-/underscore-1.9.2.tgz",
+          "integrity": "sha512-D39qtimx0c1fI3ya1Lnhk3E9nONswSKhnffBI0gME9C99fYOkNi04xs8K6pePLhvl1frbDemkaBQ5ikWllR2HQ==",
+          "dev": true
         }
       }
     },
@@ -1696,7 +1616,7 @@
       "integrity": "sha1-q2E+1Zd9x0h+hbPBL2qOqNsq3jE=",
       "dev": true,
       "requires": {
-        "mkdirp": "0.3.5"
+        "mkdirp": "~0.3.5"
       },
       "dependencies": {
         "mkdirp": {
@@ -1714,19 +1634,19 @@
       "dev": true
     },
     "js-yaml": {
-      "version": "3.10.0",
-      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.10.0.tgz",
-      "integrity": "sha512-O2v52ffjLa9VeM43J4XocZE//WT9N0IiwDa3KSHH7Tu8CtH+1qM8SIZvnsTh6v+4yFy5KUY3BHUVwjpfAWsjIA==",
+      "version": "3.13.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
+      "integrity": "sha512-YfbcO7jXDdyj0DGxYVSlSeQNHbD7XPWvrVWeVUujrQEoZzWJIRrCPoyk6kL6IAjAG2IolMK4T0hNUe0HOUs5Jw==",
       "dev": true,
       "requires": {
-        "argparse": "1.0.9",
-        "esprima": "4.0.0"
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
       },
       "dependencies": {
         "esprima": {
-          "version": "4.0.0",
-          "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.0.tgz",
-          "integrity": "sha512-oftTcaMu/EGrEIu904mWteKIv8vMuOgGYo7EhVJJN00R/EED9DCua/xxHRdYnKtcECzVg7xOWhflvJMnqcFZjw==",
+          "version": "4.0.1",
+          "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.1.tgz",
+          "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A==",
           "dev": true
         }
       }
@@ -1743,7 +1663,7 @@
       "integrity": "sha1-mnWdOcXy/1A/1TAGRu1EX4jE+a8=",
       "dev": true,
       "requires": {
-        "jsonify": "0.0.0"
+        "jsonify": "~0.0.0"
       }
     },
     "json3": {
@@ -1781,7 +1701,7 @@
       "integrity": "sha1-KaZ8CxJ7+lK907U7e4yGWamghPg=",
       "dev": true,
       "requires": {
-        "nan": "2.0.9"
+        "nan": "~2.0"
       }
     },
     "kind-of": {
@@ -1790,7 +1710,7 @@
       "integrity": "sha1-MeohpzS6ubuw8yRm2JOupR5KPGQ=",
       "dev": true,
       "requires": {
-        "is-buffer": "1.1.5"
+        "is-buffer": "^1.1.5"
       }
     },
     "lazy-cache": {
@@ -1805,14 +1725,15 @@
       "integrity": "sha1-OwmSTt+fCDwEkP3UwLxEIeBHZO4=",
       "dev": true,
       "requires": {
-        "prelude-ls": "1.1.2",
-        "type-check": "0.3.2"
+        "prelude-ls": "~1.1.2",
+        "type-check": "~0.3.2"
       }
     },
     "lodash": {
       "version": "4.17.10",
       "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.10.tgz",
-      "integrity": "sha512-UejweD1pDoXu+AD825lWwp4ZGtSwgnpZxb3JDViD7StjQz+Nb/6l093lx4OQ0foGWNRoc19mWy7BzL+UAK2iVg=="
+      "integrity": "sha512-UejweD1pDoXu+AD825lWwp4ZGtSwgnpZxb3JDViD7StjQz+Nb/6l093lx4OQ0foGWNRoc19mWy7BzL+UAK2iVg==",
+      "dev": true
     },
     "lodash._baseassign": {
       "version": "3.2.0",
@@ -1820,8 +1741,8 @@
       "integrity": "sha1-jDigmVAPIVrQnlnxci/QxSv+Ck4=",
       "dev": true,
       "requires": {
-        "lodash._basecopy": "3.0.1",
-        "lodash.keys": "3.1.2"
+        "lodash._basecopy": "^3.0.0",
+        "lodash.keys": "^3.0.0"
       }
     },
     "lodash._basecopy": {
@@ -1854,9 +1775,9 @@
       "integrity": "sha1-1/KEnw29p+BGgruM1yqwIkYd6+c=",
       "dev": true,
       "requires": {
-        "lodash._baseassign": "3.2.0",
-        "lodash._basecreate": "3.0.3",
-        "lodash._isiterateecall": "3.0.9"
+        "lodash._baseassign": "^3.0.0",
+        "lodash._basecreate": "^3.0.0",
+        "lodash._isiterateecall": "^3.0.0"
       }
     },
     "lodash.get": {
@@ -1882,9 +1803,9 @@
       "integrity": "sha1-TbwEcrFWvlCgsoaFXRvQsMZWCYo=",
       "dev": true,
       "requires": {
-        "lodash._getnative": "3.9.1",
-        "lodash.isarguments": "3.1.0",
-        "lodash.isarray": "3.0.4"
+        "lodash._getnative": "^3.0.0",
+        "lodash.isarguments": "^3.0.0",
+        "lodash.isarray": "^3.0.0"
       }
     },
     "longest": {
@@ -1894,27 +1815,21 @@
       "dev": true
     },
     "loose-envify": {
-      "version": "1.3.1",
-      "resolved": "https://registry.npmjs.org/loose-envify/-/loose-envify-1.3.1.tgz",
-      "integrity": "sha1-0aitM/qc4OcT1l/dCsi3SNR4yEg=",
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/loose-envify/-/loose-envify-1.4.0.tgz",
+      "integrity": "sha512-lyuxPGr/Wfhrlem2CL/UcnUc1zcqKAImBDzukY7Y5F/yQiNdko6+fRLevlw1HgMySw7f611UIY408EtxRSoK3Q==",
       "dev": true,
       "requires": {
-        "js-tokens": "3.0.2"
+        "js-tokens": "^3.0.0 || ^4.0.0"
       }
     },
-    "lru-cache": {
-      "version": "2.7.3",
-      "resolved": "https://registry.npmjs.org/lru-cache/-/lru-cache-2.7.3.tgz",
-      "integrity": "sha1-bUUk6LlV+V1PW1iFHOId1y+06VI=",
-      "dev": true
-    },
     "markdown": {
       "version": "0.5.0",
       "resolved": "https://registry.npmjs.org/markdown/-/markdown-0.5.0.tgz",
       "integrity": "sha1-KCBbVlqK51kt4gdGPWY33BgnIrI=",
       "dev": true,
       "requires": {
-        "nopt": "2.1.2"
+        "nopt": "~2.1.1"
       },
       "dependencies": {
         "nopt": {
@@ -1923,7 +1838,7 @@
           "integrity": "sha1-bMzZd7gBMqB3MdbozljCyDA8+a8=",
           "dev": true,
           "requires": {
-            "abbrev": "1.0.9"
+            "abbrev": "1"
           }
         }
       }
@@ -1953,24 +1868,24 @@
       "dev": true
     },
     "mime": {
-      "version": "2.0.3",
-      "resolved": "https://registry.npmjs.org/mime/-/mime-2.0.3.tgz",
-      "integrity": "sha512-TrpAd/vX3xaLPDgVRm6JkZwLR0KHfukMdU2wTEbqMDdCnY6Yo3mE+mjs9YE6oMNw2QRfXVeBEYpmpO94BIqiug==",
+      "version": "2.4.4",
+      "resolved": "https://registry.npmjs.org/mime/-/mime-2.4.4.tgz",
+      "integrity": "sha512-LRxmNwziLPT828z+4YkNzloCFC2YM4wrB99k+AV5ZbEyfGNWfG8SO1FUXLmLDBSo89NrJZ4DIWeLjy1CHGhMGA==",
       "dev": true
     },
     "mime-db": {
-      "version": "1.30.0",
-      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.30.0.tgz",
-      "integrity": "sha1-dMZD2i3Z1qRTmZY0ZbJtXKfXHwE=",
+      "version": "1.43.0",
+      "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.43.0.tgz",
+      "integrity": "sha512-+5dsGEEovYbT8UY9yD7eE4XTc4UwJ1jBYlgaQQF38ENsKR3wj/8q8RFZrF9WIZpB2V1ArTVFUva8sAul1NzRzQ==",
       "dev": true
     },
     "mime-types": {
-      "version": "2.1.17",
-      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.17.tgz",
-      "integrity": "sha1-Cdejk/A+mVp5+K+Fe3Cp4KsWVXo=",
+      "version": "2.1.26",
+      "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.26.tgz",
+      "integrity": "sha512-01paPWYgLrkqAyrlDorC1uDwl2p3qZT7yl806vW7DvDoxwXi46jsjFbg+WdwotBIk6/MbEhO/dh5aZ5sNj/dWQ==",
       "dev": true,
       "requires": {
-        "mime-db": "1.30.0"
+        "mime-db": "1.43.0"
       }
     },
     "minimatch": {
@@ -1979,7 +1894,7 @@
       "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
       "dev": true,
       "requires": {
-        "brace-expansion": "1.1.8"
+        "brace-expansion": "^1.1.7"
       }
     },
     "minimist": {
@@ -2022,7 +1937,7 @@
           "integrity": "sha1-nJkJQXbhIkDLItbFFGCYQA/g99Q=",
           "dev": true,
           "requires": {
-            "graceful-readlink": "1.0.1"
+            "graceful-readlink": ">= 1.0.0"
           }
         },
         "debug": {
@@ -2040,12 +1955,12 @@
           "integrity": "sha1-tCAqaQmbu00pKnwblbZoK2fr3JU=",
           "dev": true,
           "requires": {
-            "fs.realpath": "1.0.0",
-            "inflight": "1.0.6",
-            "inherits": "2.0.3",
-            "minimatch": "3.0.4",
-            "once": "1.4.0",
-            "path-is-absolute": "1.0.1"
+            "fs.realpath": "^1.0.0",
+            "inflight": "^1.0.4",
+            "inherits": "2",
+            "minimatch": "^3.0.2",
+            "once": "^1.3.0",
+            "path-is-absolute": "^1.0.0"
           }
         },
         "ms": {
@@ -2060,7 +1975,7 @@
           "integrity": "sha1-cqJiiU2dQIuVbKBf83su2KbiotU=",
           "dev": true,
           "requires": {
-            "has-flag": "1.0.0"
+            "has-flag": "^1.0.0"
           }
         }
       }
@@ -2080,8 +1995,8 @@
       "resolved": "https://registry.npmjs.org/mongodb-core/-/mongodb-core-2.1.18.tgz",
       "integrity": "sha1-TEYTm986HwMt7ZHbSfOO7AFlkFA=",
       "requires": {
-        "bson": "1.0.4",
-        "require_optional": "1.0.1"
+        "bson": "~1.0.4",
+        "require_optional": "~1.0.0"
       }
     },
     "mongodb-topology-manager": {
@@ -2090,15 +2005,15 @@
       "integrity": "sha1-GXDHRbhe36SAEQRaj+bQP2W1ofA=",
       "dev": true,
       "requires": {
-        "babel-core": "6.26.0",
-        "babel-polyfill": "6.26.0",
-        "bluebird": "3.5.0",
-        "co": "4.6.0",
-        "es6-promise": "3.2.1",
+        "babel-core": "^6.10.4",
+        "babel-polyfill": "^6.9.1",
+        "bluebird": "^3.4.1",
+        "co": "^4.6.0",
+        "es6-promise": "^3.2.1",
         "kerberos": "0.0.17",
-        "mkdirp": "0.5.1",
-        "mongodb-core": "1.3.21",
-        "rimraf": "2.6.2"
+        "mkdirp": "^0.5.1",
+        "mongodb-core": "^1.2.24",
+        "rimraf": "^2.4.3"
       },
       "dependencies": {
         "bson": {
@@ -2113,18 +2028,12 @@
           "integrity": "sha1-/hKee+4rOybBQJ3gKrYNA/YpHMo=",
           "dev": true,
           "requires": {
-            "bson": "0.4.23",
-            "require_optional": "1.0.1"
+            "bson": "~0.4.23",
+            "require_optional": "~1.0.0"
           }
         }
       }
     },
-    "mongoose-long": {
-      "version": "0.1.1",
-      "resolved": "https://registry.npmjs.org/mongoose-long/-/mongoose-long-0.1.1.tgz",
-      "integrity": "sha1-zDLgWwz1DIXiWhk1nUOpNv6VBaM=",
-      "dev": true
-    },
     "mpath": {
       "version": "0.5.1",
       "resolved": "https://registry.npmjs.org/mpath/-/mpath-0.5.1.tgz",
@@ -2176,9 +2085,21 @@
       "dev": true
     },
     "negotiator": {
-      "version": "0.6.1",
-      "resolved": "https://registry.npmjs.org/negotiator/-/negotiator-0.6.1.tgz",
-      "integrity": "sha1-KzJxhOiZIQEXeyhWP7XnECrNDKk=",
+      "version": "0.6.2",
+      "resolved": "https://registry.npmjs.org/negotiator/-/negotiator-0.6.2.tgz",
+      "integrity": "sha512-hZXc7K2e+PgeI1eDBe/10Ard4ekbfrrqG8Ep+8Jmf4JID2bNg7NvCPOZN+kfF574pFQI7mum2AUqDidoKqcTOw==",
+      "dev": true
+    },
+    "neo-async": {
+      "version": "2.6.1",
+      "resolved": "https://registry.npmjs.org/neo-async/-/neo-async-2.6.1.tgz",
+      "integrity": "sha512-iyam8fBuCUpWeKPGpaNMetEocMt364qkCsfL9JuhjXX6dRnguRVOfk2GZaDpPjcOKiiXCPINZC1GczQ7iTq3Zw==",
+      "dev": true
+    },
+    "next-tick": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/next-tick/-/next-tick-1.0.0.tgz",
+      "integrity": "sha1-yobR/ogoFpsBICCOPchCS524NCw=",
       "dev": true
     },
     "node-static": {
@@ -2187,9 +2108,9 @@
       "integrity": "sha1-kwgdg02b2dg3N3mN89o81TjokIo=",
       "dev": true,
       "requires": {
-        "colors": "1.1.2",
-        "mime": "2.0.3",
-        "optimist": "0.6.1"
+        "colors": ">=0.6.0",
+        "mime": ">=1.2.9",
+        "optimist": ">=0.3.4"
       }
     },
     "nopt": {
@@ -2198,7 +2119,7 @@
       "integrity": "sha1-xkZdvwirzU2zWTF/eaxopkayj/k=",
       "dev": true,
       "requires": {
-        "abbrev": "1.0.9"
+        "abbrev": "1"
       }
     },
     "nsp": {
@@ -2207,17 +2128,17 @@
       "integrity": "sha512-jvjDg2Gsw4coD/iZ5eQddsDlkvnwMCNnpG05BproSnuG+Gr1bSQMwWMcQeYje+qdDl3XznmhblMPLpZLecTORQ==",
       "dev": true,
       "requires": {
-        "chalk": "1.1.3",
-        "cli-table": "0.3.1",
-        "cvss": "1.0.2",
-        "https-proxy-agent": "1.0.0",
-        "joi": "6.10.1",
-        "nodesecurity-npm-utils": "5.0.0",
-        "path-is-absolute": "1.0.1",
-        "rc": "1.2.1",
-        "semver": "5.4.1",
-        "subcommand": "2.1.0",
-        "wreck": "6.3.0"
+        "chalk": "^1.1.1",
+        "cli-table": "^0.3.1",
+        "cvss": "^1.0.0",
+        "https-proxy-agent": "^1.0.0",
+        "joi": "^6.9.1",
+        "nodesecurity-npm-utils": "^5.0.0",
+        "path-is-absolute": "^1.0.0",
+        "rc": "^1.1.2",
+        "semver": "^5.0.3",
+        "subcommand": "^2.0.3",
+        "wreck": "^6.3.0"
       },
       "dependencies": {
         "agent-base": {
@@ -2226,8 +2147,8 @@
           "integrity": "sha1-1t4Q1a9hMtW9aSQn1G/FOFOQlMc=",
           "dev": true,
           "requires": {
-            "extend": "3.0.1",
-            "semver": "5.0.3"
+            "extend": "~3.0.0",
+            "semver": "~5.0.1"
           },
           "dependencies": {
             "semver": {
@@ -2256,7 +2177,7 @@
           "integrity": "sha1-OciRjO/1eZ+D+UkqhI9iWt0Mdm8=",
           "dev": true,
           "requires": {
-            "hoek": "2.16.3"
+            "hoek": "2.x.x"
           }
         },
         "chalk": {
@@ -2265,11 +2186,11 @@
           "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
           "dev": true,
           "requires": {
-            "ansi-styles": "2.2.1",
-            "escape-string-regexp": "1.0.5",
-            "has-ansi": "2.0.0",
-            "strip-ansi": "3.0.1",
-            "supports-color": "2.0.0"
+            "ansi-styles": "^2.2.1",
+            "escape-string-regexp": "^1.0.2",
+            "has-ansi": "^2.0.0",
+            "strip-ansi": "^3.0.0",
+            "supports-color": "^2.0.0"
           }
         },
         "cli-table": {
@@ -2332,7 +2253,7 @@
           "integrity": "sha1-NPUEnOHs3ysGSa8+8k5F7TVBbZE=",
           "dev": true,
           "requires": {
-            "ansi-regex": "2.1.1"
+            "ansi-regex": "^2.0.0"
           }
         },
         "hoek": {
@@ -2347,9 +2268,9 @@
           "integrity": "sha1-NffabEjOTdv6JkiRrFk+5f+GceY=",
           "dev": true,
           "requires": {
-            "agent-base": "2.1.1",
-            "debug": "2.6.9",
-            "extend": "3.0.1"
+            "agent-base": "2",
+            "debug": "2",
+            "extend": "3"
           }
         },
         "ini": {
@@ -2370,10 +2291,10 @@
           "integrity": "sha1-TVDDGAeRIgAP5fFq8f+OGRe3fgY=",
           "dev": true,
           "requires": {
-            "hoek": "2.16.3",
-            "isemail": "1.2.0",
-            "moment": "2.18.1",
-            "topo": "1.1.0"
+            "hoek": "2.x.x",
+            "isemail": "1.x.x",
+            "moment": "2.x.x",
+            "topo": "1.x.x"
           }
         },
         "minimist": {
@@ -2412,10 +2333,10 @@
           "integrity": "sha1-LgPo5C7kULjLPc5lvhv4l04d/ZU=",
           "dev": true,
           "requires": {
-            "deep-extend": "0.4.2",
-            "ini": "1.3.4",
-            "minimist": "1.2.0",
-            "strip-json-comments": "2.0.1"
+            "deep-extend": "~0.4.0",
+            "ini": "~1.3.0",
+            "minimist": "^1.2.0",
+            "strip-json-comments": "~2.0.1"
           }
         },
         "semver": {
@@ -2430,7 +2351,7 @@
           "integrity": "sha1-ajhfuIU9lS1f8F0Oiq+UJ43GPc8=",
           "dev": true,
           "requires": {
-            "ansi-regex": "2.1.1"
+            "ansi-regex": "^2.0.0"
           }
         },
         "strip-json-comments": {
@@ -2445,10 +2366,10 @@
           "integrity": "sha1-XkzspaN3njNlsVEeBfhmh3MC92A=",
           "dev": true,
           "requires": {
-            "cliclopts": "1.1.1",
-            "debug": "2.6.9",
-            "minimist": "1.2.0",
-            "xtend": "4.0.1"
+            "cliclopts": "^1.1.0",
+            "debug": "^2.1.3",
+            "minimist": "^1.2.0",
+            "xtend": "^4.0.0"
           }
         },
         "supports-color": {
@@ -2463,7 +2384,7 @@
           "integrity": "sha1-6ddRYV0buH3IZdsYL6HKCl71NtU=",
           "dev": true,
           "requires": {
-            "hoek": "2.16.3"
+            "hoek": "2.x.x"
           }
         },
         "wreck": {
@@ -2472,8 +2393,8 @@
           "integrity": "sha1-oTaXafB7u2LWo3gzanhx/Hc8dAs=",
           "dev": true,
           "requires": {
-            "boom": "2.10.1",
-            "hoek": "2.16.3"
+            "boom": "2.x.x",
+            "hoek": "2.x.x"
           }
         },
         "xtend": {
@@ -2497,9 +2418,9 @@
       "dev": true
     },
     "object-keys": {
-      "version": "1.0.11",
-      "resolved": "https://registry.npmjs.org/object-keys/-/object-keys-1.0.11.tgz",
-      "integrity": "sha1-xUYBd4rVYPEULODgG8yotW0TQm0=",
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/object-keys/-/object-keys-1.1.1.tgz",
+      "integrity": "sha512-NuAESUOUMrlIXOfHKzD6bpPu3tYt3xvjNdRIQ+FeT0lNb4K8WR70CaDxhuNguS2XG+GjkyMwOzsN5ZktImfhLA==",
       "dev": true
     },
     "on-finished": {
@@ -2517,7 +2438,7 @@
       "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
       "dev": true,
       "requires": {
-        "wrappy": "1.0.2"
+        "wrappy": "1"
       }
     },
     "onetime": {
@@ -2532,8 +2453,8 @@
       "integrity": "sha1-2j6nRob6IaGaERwybpDrFaAZZoY=",
       "dev": true,
       "requires": {
-        "minimist": "0.0.8",
-        "wordwrap": "0.0.3"
+        "minimist": "~0.0.1",
+        "wordwrap": "~0.0.2"
       },
       "dependencies": {
         "wordwrap": {
@@ -2545,17 +2466,17 @@
       }
     },
     "optionator": {
-      "version": "0.8.2",
-      "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.8.2.tgz",
-      "integrity": "sha1-NkxeQJ0/TWMB1sC0wFu6UBgK62Q=",
+      "version": "0.8.3",
+      "resolved": "https://registry.npmjs.org/optionator/-/optionator-0.8.3.tgz",
+      "integrity": "sha512-+IW9pACdk3XWmmTXG8m3upGUJst5XRGzxMRjXzAuJ1XnIFNvfhjjIuYkDvysnPQ7qzqVzLt78BCruntqRhWQbA==",
       "dev": true,
       "requires": {
-        "deep-is": "0.1.3",
-        "fast-levenshtein": "2.0.6",
-        "levn": "0.3.0",
-        "prelude-ls": "1.1.2",
-        "type-check": "0.3.2",
-        "wordwrap": "1.0.0"
+        "deep-is": "~0.1.3",
+        "fast-levenshtein": "~2.0.6",
+        "levn": "~0.3.0",
+        "prelude-ls": "~1.1.2",
+        "type-check": "~0.3.2",
+        "word-wrap": "~1.2.3"
       }
     },
     "os-homedir": {
@@ -2571,9 +2492,9 @@
       "dev": true
     },
     "parseurl": {
-      "version": "1.3.2",
-      "resolved": "https://registry.npmjs.org/parseurl/-/parseurl-1.3.2.tgz",
-      "integrity": "sha1-/CidTtiZMRlGDBViUyYs3I3mW/M=",
+      "version": "1.3.3",
+      "resolved": "https://registry.npmjs.org/parseurl/-/parseurl-1.3.3.tgz",
+      "integrity": "sha512-CiyeOxFT/JZyN5m0z9PfXw4SCBJ6Sygz1Dpl0wqjlhDEGGBP1GnsUVEL0p63hoG1fcj3fHynXi9NYO4nWOL+qQ==",
       "dev": true
     },
     "path-is-absolute": {
@@ -2589,9 +2510,9 @@
       "dev": true
     },
     "path-parse": {
-      "version": "1.0.5",
-      "resolved": "https://registry.npmjs.org/path-parse/-/path-parse-1.0.5.tgz",
-      "integrity": "sha1-PBrfhx6pzWyUMbbqK9dKD/BVxME=",
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/path-parse/-/path-parse-1.0.6.tgz",
+      "integrity": "sha512-GSmOT2EbHrINBf9SR7CDELwlJ8AENk3Qn7OikK4nFYAu3Ote2+JYNVvkpAEQm3/TLNEJFD/xZJjzyxg3KBWOzw==",
       "dev": true
     },
     "path-to-regexp": {
@@ -2600,31 +2521,10 @@
       "integrity": "sha1-32BBeABfUi8V60SQ5yR6G/qmf4w=",
       "dev": true
     },
-    "pify": {
-      "version": "2.3.0",
-      "resolved": "https://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
-      "integrity": "sha1-7RQaasBDqEnqWISY59yosVMw6Qw=",
-      "dev": true
-    },
-    "pinkie": {
-      "version": "2.0.4",
-      "resolved": "https://registry.npmjs.org/pinkie/-/pinkie-2.0.4.tgz",
-      "integrity": "sha1-clVrgM+g1IqXToDnckjoDtT3+HA=",
-      "dev": true
-    },
-    "pinkie-promise": {
-      "version": "2.0.1",
-      "resolved": "https://registry.npmjs.org/pinkie-promise/-/pinkie-promise-2.0.1.tgz",
-      "integrity": "sha1-ITXW36ejWMBprJsXh3YogihFD/o=",
-      "dev": true,
-      "requires": {
-        "pinkie": "2.0.4"
-      }
-    },
     "platform": {
-      "version": "1.3.4",
-      "resolved": "https://registry.npmjs.org/platform/-/platform-1.3.4.tgz",
-      "integrity": "sha1-bw+xftqqSPIUQrOpdcBjEw8cPr0=",
+      "version": "1.3.5",
+      "resolved": "https://registry.npmjs.org/platform/-/platform-1.3.5.tgz",
+      "integrity": "sha512-TuvHS8AOIZNAlE77WUDiR4rySV/VMptyMfcfeoMgs4P8apaZM3JrnbzBiixKUv+XR6i+BXrQh8WAnjaSPFO65Q==",
       "dev": true
     },
     "pluralize": {
@@ -2639,52 +2539,44 @@
       "integrity": "sha1-SC7gmKmHfoz6ciQshJm5PyBwnE4=",
       "dev": true,
       "requires": {
-        "define-properties": "1.1.2",
-        "empower": "1.2.3",
-        "power-assert-formatter": "1.4.1",
-        "universal-deep-strict-equal": "1.2.2",
-        "xtend": "4.0.1"
+        "define-properties": "^1.1.2",
+        "empower": "^1.1.0",
+        "power-assert-formatter": "^1.3.1",
+        "universal-deep-strict-equal": "^1.2.1",
+        "xtend": "^4.0.0"
       }
     },
     "power-assert-context-formatter": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/power-assert-context-formatter/-/power-assert-context-formatter-1.1.1.tgz",
-      "integrity": "sha1-7bo1LT7YpgMRTWZyZazOYNaJzN8=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-context-formatter/-/power-assert-context-formatter-1.2.0.tgz",
+      "integrity": "sha512-HLNEW8Bin+BFCpk/zbyKwkEu9W8/zThIStxGo7weYcFkKgMuGCHUJhvJeBGXDZf0Qm2xis4pbnnciGZiX0EpSg==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "power-assert-context-traversal": "1.1.1"
+        "core-js": "^2.0.0",
+        "power-assert-context-traversal": "^1.2.0"
       }
     },
     "power-assert-context-reducer-ast": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/power-assert-context-reducer-ast/-/power-assert-context-reducer-ast-1.1.2.tgz",
-      "integrity": "sha1-SEqZ4m9Jc/+IMuXFzHVnAuYJQXQ=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-context-reducer-ast/-/power-assert-context-reducer-ast-1.2.0.tgz",
+      "integrity": "sha512-EgOxmZ/Lb7tw4EwSKX7ZnfC0P/qRZFEG28dx/690qvhmOJ6hgThYFm5TUWANDLK5NiNKlPBi5WekVGd2+5wPrw==",
       "dev": true,
       "requires": {
-        "acorn": "4.0.13",
-        "acorn-es7-plugin": "1.1.7",
-        "core-js": "2.5.1",
-        "espurify": "1.7.0",
-        "estraverse": "4.2.0"
-      },
-      "dependencies": {
-        "acorn": {
-          "version": "4.0.13",
-          "resolved": "https://registry.npmjs.org/acorn/-/acorn-4.0.13.tgz",
-          "integrity": "sha1-EFSVrlNh1pe9GVyCUZLhrX8lN4c=",
-          "dev": true
-        }
+        "acorn": "^5.0.0",
+        "acorn-es7-plugin": "^1.0.12",
+        "core-js": "^2.0.0",
+        "espurify": "^1.6.0",
+        "estraverse": "^4.2.0"
       }
     },
     "power-assert-context-traversal": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/power-assert-context-traversal/-/power-assert-context-traversal-1.1.1.tgz",
-      "integrity": "sha1-iMq8oNE7Y1nwfT0+ivppkmRXftk=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-context-traversal/-/power-assert-context-traversal-1.2.0.tgz",
+      "integrity": "sha512-NFoHU6g2umNajiP2l4qb0BRWD773Aw9uWdWYH9EQsVwIZnog5bd2YYLFCVvaxWpwNzWeEfZIon2xtyc63026pQ==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "estraverse": "4.2.0"
+        "core-js": "^2.0.0",
+        "estraverse": "^4.1.0"
       }
     },
     "power-assert-formatter": {
@@ -2693,23 +2585,23 @@
       "integrity": "sha1-XcEl7VCj37HdomwZNH879Y7CiEo=",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "power-assert-context-formatter": "1.1.1",
-        "power-assert-context-reducer-ast": "1.1.2",
-        "power-assert-renderer-assertion": "1.1.1",
-        "power-assert-renderer-comparison": "1.1.1",
-        "power-assert-renderer-diagram": "1.1.2",
-        "power-assert-renderer-file": "1.1.1"
+        "core-js": "^2.0.0",
+        "power-assert-context-formatter": "^1.0.7",
+        "power-assert-context-reducer-ast": "^1.0.7",
+        "power-assert-renderer-assertion": "^1.0.7",
+        "power-assert-renderer-comparison": "^1.0.7",
+        "power-assert-renderer-diagram": "^1.0.7",
+        "power-assert-renderer-file": "^1.0.7"
       }
     },
     "power-assert-renderer-assertion": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/power-assert-renderer-assertion/-/power-assert-renderer-assertion-1.1.1.tgz",
-      "integrity": "sha1-y/wOd+AIao+Wrz8djme57n4ozpg=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-renderer-assertion/-/power-assert-renderer-assertion-1.2.0.tgz",
+      "integrity": "sha512-3F7Q1ZLmV2ZCQv7aV7NJLNK9G7QsostrhOU7U0RhEQS/0vhEqrRg2jEJl1jtUL4ZyL2dXUlaaqrmPv5r9kRvIg==",
       "dev": true,
       "requires": {
-        "power-assert-renderer-base": "1.1.1",
-        "power-assert-util-string-width": "1.1.1"
+        "power-assert-renderer-base": "^1.1.1",
+        "power-assert-util-string-width": "^1.2.0"
       }
     },
     "power-assert-renderer-base": {
@@ -2719,46 +2611,46 @@
       "dev": true
     },
     "power-assert-renderer-comparison": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/power-assert-renderer-comparison/-/power-assert-renderer-comparison-1.1.1.tgz",
-      "integrity": "sha1-10Odl9hRVr5OMKAPL7WnJRTOPAg=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-renderer-comparison/-/power-assert-renderer-comparison-1.2.0.tgz",
+      "integrity": "sha512-7c3RKPDBKK4E3JqdPtYRE9cM8AyX4LC4yfTvvTYyx8zSqmT5kJnXwzR0yWQLOavACllZfwrAGQzFiXPc5sWa+g==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "diff-match-patch": "1.0.0",
-        "power-assert-renderer-base": "1.1.1",
-        "stringifier": "1.3.0",
-        "type-name": "2.0.2"
+        "core-js": "^2.0.0",
+        "diff-match-patch": "^1.0.0",
+        "power-assert-renderer-base": "^1.1.1",
+        "stringifier": "^1.3.0",
+        "type-name": "^2.0.1"
       }
     },
     "power-assert-renderer-diagram": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/power-assert-renderer-diagram/-/power-assert-renderer-diagram-1.1.2.tgz",
-      "integrity": "sha1-ZV+PcRk1qbbVQbhjJ2VHF8Y3qYY=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-renderer-diagram/-/power-assert-renderer-diagram-1.2.0.tgz",
+      "integrity": "sha512-JZ6PC+DJPQqfU6dwSmpcoD7gNnb/5U77bU5KgNwPPa+i1Pxiz6UuDeM3EUBlhZ1HvH9tMjI60anqVyi5l2oNdg==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "power-assert-renderer-base": "1.1.1",
-        "power-assert-util-string-width": "1.1.1",
-        "stringifier": "1.3.0"
+        "core-js": "^2.0.0",
+        "power-assert-renderer-base": "^1.1.1",
+        "power-assert-util-string-width": "^1.2.0",
+        "stringifier": "^1.3.0"
       }
     },
     "power-assert-renderer-file": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/power-assert-renderer-file/-/power-assert-renderer-file-1.1.1.tgz",
-      "integrity": "sha1-o34rvReMys0E5427eckv40kzxec=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-renderer-file/-/power-assert-renderer-file-1.2.0.tgz",
+      "integrity": "sha512-/oaVrRbeOtGoyyd7e4IdLP/jIIUFJdqJtsYzP9/88R39CMnfF/S/rUc8ZQalENfUfQ/wQHu+XZYRMaCEZmEesg==",
       "dev": true,
       "requires": {
-        "power-assert-renderer-base": "1.1.1"
+        "power-assert-renderer-base": "^1.1.1"
       }
     },
     "power-assert-util-string-width": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/power-assert-util-string-width/-/power-assert-util-string-width-1.1.1.tgz",
-      "integrity": "sha1-vmWet5N/3S5smncmjar2S9W3xZI=",
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/power-assert-util-string-width/-/power-assert-util-string-width-1.2.0.tgz",
+      "integrity": "sha512-lX90G0igAW0iyORTILZ/QjZWsa1MZ6VVY3L0K86e2eKun3S4LKPH4xZIl8fdeMYLfOjkaszbNSzf1uugLeAm2A==",
       "dev": true,
       "requires": {
-        "eastasianwidth": "0.1.1"
+        "eastasianwidth": "^0.2.0"
       }
     },
     "prelude-ls": {
@@ -2768,9 +2660,9 @@
       "dev": true
     },
     "private": {
-      "version": "0.1.7",
-      "resolved": "https://registry.npmjs.org/private/-/private-0.1.7.tgz",
-      "integrity": "sha1-aM5eih7woju1cMwoU3tTMqumPvE=",
+      "version": "0.1.8",
+      "resolved": "https://registry.npmjs.org/private/-/private-0.1.8.tgz",
+      "integrity": "sha512-VvivMrbvd2nKkiG38qjULzlc+4Vx4wm/whI9pQD35YrARNnhxeiRktSOhSukRLFNlzg6Br/cJPet5J/u19r/mg==",
       "dev": true
     },
     "process-nextick-args": {
@@ -2785,13 +2677,13 @@
       "dev": true
     },
     "proxy-addr": {
-      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/proxy-addr/-/proxy-addr-2.0.2.tgz",
-      "integrity": "sha1-ZXFQT0e7mI7IGAJT+F3X4UlSvew=",
+      "version": "2.0.5",
+      "resolved": "https://registry.npmjs.org/proxy-addr/-/proxy-addr-2.0.5.tgz",
+      "integrity": "sha512-t/7RxHXPH6cJtP0pRG6smSr9QJidhB+3kXu0KgXnbGYMgzEnUxRQ4/LDdfOwZEMyIh3/xHb8PX3t+lfL9z+YVQ==",
       "dev": true,
       "requires": {
-        "forwarded": "0.1.2",
-        "ipaddr.js": "1.5.2"
+        "forwarded": "~0.1.2",
+        "ipaddr.js": "1.9.0"
       }
     },
     "q": {
@@ -2801,26 +2693,26 @@
       "dev": true
     },
     "qs": {
-      "version": "6.5.1",
-      "resolved": "https://registry.npmjs.org/qs/-/qs-6.5.1.tgz",
-      "integrity": "sha512-eRzhrN1WSINYCDCbrz796z37LOe3m5tmW7RQf6oBntukAG1nmovJvhnwHHRMAfeoItc1m2Hk02WER2aQ/iqs+A==",
+      "version": "6.7.0",
+      "resolved": "https://registry.npmjs.org/qs/-/qs-6.7.0.tgz",
+      "integrity": "sha512-VCdBRNFTX1fyE7Nb6FYoURo/SPe62QCaAyzJvUjwRaIsc+NePBEniHlvxFmmX56+HZphIGtV0XeCirBtpDrTyQ==",
       "dev": true
     },
     "range-parser": {
-      "version": "1.2.0",
-      "resolved": "https://registry.npmjs.org/range-parser/-/range-parser-1.2.0.tgz",
-      "integrity": "sha1-9JvmtIeJTdxA3MlKMi9hEJLgDV4=",
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/range-parser/-/range-parser-1.2.1.tgz",
+      "integrity": "sha512-Hrgsx+orqoygnmhFbKaHE6c296J+HTAQXoxEF6gNupROmmGJRoyzfG3ccAveqCBrwr/2yxQ5BVd/GTl5agOwSg==",
       "dev": true
     },
     "raw-body": {
-      "version": "2.3.2",
-      "resolved": "https://registry.npmjs.org/raw-body/-/raw-body-2.3.2.tgz",
-      "integrity": "sha1-vNYMd9Prk83gBQKVw/N5OJvIj4k=",
+      "version": "2.4.0",
+      "resolved": "https://registry.npmjs.org/raw-body/-/raw-body-2.4.0.tgz",
+      "integrity": "sha512-4Oz8DUIwdvoa5qMJelxipzi/iJIi40O5cGV1wNYp5hvZP8ZN0T+jiNkL0QepXs+EsQ9XJ8ipEDoiH70ySUJP3Q==",
       "dev": true,
       "requires": {
-        "bytes": "3.0.0",
-        "http-errors": "1.6.2",
-        "iconv-lite": "0.4.19",
+        "bytes": "3.1.0",
+        "http-errors": "1.7.2",
+        "iconv-lite": "0.4.24",
         "unpipe": "1.0.0"
       }
     },
@@ -2829,13 +2721,13 @@
       "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.2.7.tgz",
       "integrity": "sha1-BwV6y+JGeyIELTb5jFrVBwVOlbE=",
       "requires": {
-        "buffer-shims": "1.0.0",
-        "core-util-is": "1.0.2",
-        "inherits": "2.0.3",
-        "isarray": "1.0.0",
-        "process-nextick-args": "1.0.7",
-        "string_decoder": "1.0.3",
-        "util-deprecate": "1.0.2"
+        "buffer-shims": "~1.0.0",
+        "core-util-is": "~1.0.0",
+        "inherits": "~2.0.1",
+        "isarray": "~1.0.0",
+        "process-nextick-args": "~1.0.6",
+        "string_decoder": "~1.0.0",
+        "util-deprecate": "~1.0.1"
       }
     },
     "readline2": {
@@ -2844,15 +2736,15 @@
       "integrity": "sha1-QQWWCP/BVHV7cV2ZidGZ/783LjU=",
       "dev": true,
       "requires": {
-        "code-point-at": "1.1.0",
-        "is-fullwidth-code-point": "1.0.0",
+        "code-point-at": "^1.0.0",
+        "is-fullwidth-code-point": "^1.0.0",
         "mute-stream": "0.0.5"
       }
     },
     "regenerator-runtime": {
-      "version": "0.11.0",
-      "resolved": "https://registry.npmjs.org/regenerator-runtime/-/regenerator-runtime-0.11.0.tgz",
-      "integrity": "sha512-/aA0kLeRb5N9K0d4fw7ooEbI+xDe+DKD499EQqygGqeS8N3xto15p09uY2xj7ixP81sNPXvRLnAQIqdVStgb1A==",
+      "version": "0.11.1",
+      "resolved": "https://registry.npmjs.org/regenerator-runtime/-/regenerator-runtime-0.11.1.tgz",
+      "integrity": "sha512-MguG95oij0fC3QV3URf4V2SDYGJhJnJGqvIIgdECeODCT98wSWDAJ94SSuVpYQUoTcGUIL6L4yNB7j1DFFHSBg==",
       "dev": true
     },
     "regexp-clone": {
@@ -2872,7 +2764,7 @@
       "integrity": "sha1-UhTFOpJtNVJwdSf7q0FdvAjQbdo=",
       "dev": true,
       "requires": {
-        "is-finite": "1.0.2"
+        "is-finite": "^1.0.0"
       }
     },
     "require-uncached": {
@@ -2881,8 +2773,8 @@
       "integrity": "sha1-Tg1W1slmL9MeQwEcS5WqSZVUIdM=",
       "dev": true,
       "requires": {
-        "caller-path": "0.1.0",
-        "resolve-from": "1.0.1"
+        "caller-path": "^0.1.0",
+        "resolve-from": "^1.0.0"
       },
       "dependencies": {
         "resolve-from": {
@@ -2898,23 +2790,23 @@
       "resolved": "https://registry.npmjs.org/require_optional/-/require_optional-1.0.1.tgz",
       "integrity": "sha512-qhM/y57enGWHAe3v/NcwML6a3/vfESLe/sGM2dII+gEO0BpKRUkWZow/tyloNqJyN6kXSl3RyyM8Ll5D/sJP8g==",
       "requires": {
-        "resolve-from": "2.0.0",
-        "semver": "5.4.1"
+        "resolve-from": "^2.0.0",
+        "semver": "^5.1.0"
       }
     },
     "requirejs": {
-      "version": "2.3.5",
-      "resolved": "https://registry.npmjs.org/requirejs/-/requirejs-2.3.5.tgz",
-      "integrity": "sha512-svnO+aNcR/an9Dpi44C7KSAy5fFGLtmPbaaCeQaklUz8BQhS64tWWIIlvEA5jrWICzlO/X9KSzSeXFnZdBu8nw==",
+      "version": "2.3.6",
+      "resolved": "https://registry.npmjs.org/requirejs/-/requirejs-2.3.6.tgz",
+      "integrity": "sha512-ipEzlWQe6RK3jkzikgCupiTbTvm4S0/CAU5GlgptkN5SO6F3u0UD0K18wy6ErDqiCyP4J4YYe1HuAShvsxePLg==",
       "dev": true
     },
     "resolve": {
-      "version": "1.4.0",
-      "resolved": "https://registry.npmjs.org/resolve/-/resolve-1.4.0.tgz",
-      "integrity": "sha512-aW7sVKPufyHqOmyyLzg/J+8606v5nevBgaliIlV7nUpVMsDnoBGV/cbSLNjZAg9q0Cfd/+easKVKQ8vOu8fn1Q==",
+      "version": "1.14.2",
+      "resolved": "https://registry.npmjs.org/resolve/-/resolve-1.14.2.tgz",
+      "integrity": "sha512-EjlOBLBO1kxsUxsKjLt7TAECyKW6fOh1VRkykQkKGzcBbjjPIxBqGh0jf7GJ3k/f5mxMqW3htMD3WdTUVtW8HQ==",
       "dev": true,
       "requires": {
-        "path-parse": "1.0.5"
+        "path-parse": "^1.0.6"
       }
     },
     "resolve-from": {
@@ -2928,8 +2820,8 @@
       "integrity": "sha1-NGYfRohjJ/7SmRR5FSJS35LapUE=",
       "dev": true,
       "requires": {
-        "exit-hook": "1.1.1",
-        "onetime": "1.1.0"
+        "exit-hook": "^1.0.0",
+        "onetime": "^1.0.0"
       }
     },
     "right-align": {
@@ -2938,30 +2830,30 @@
       "integrity": "sha1-YTObci/mo1FWiSENJOFMlhSGE+8=",
       "dev": true,
       "requires": {
-        "align-text": "0.1.4"
+        "align-text": "^0.1.1"
       }
     },
     "rimraf": {
-      "version": "2.6.2",
-      "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.2.tgz",
-      "integrity": "sha512-lreewLK/BlghmxtfH36YYVg1i8IAce4TI7oao75I1g245+6BctqTVQiBP3YUJ9C6DQOXJmkYR9X9fCLtCOJc5w==",
+      "version": "2.6.3",
+      "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.3.tgz",
+      "integrity": "sha512-mwqeW5XsA2qAejG46gYdENaxXjx9onRNCfn7L0duuP4hCuTIi/QO7PDK07KJfp1d+izWPrzEJDcSqBa0OZQriA==",
       "dev": true,
       "requires": {
-        "glob": "7.1.2"
+        "glob": "^7.1.3"
       },
       "dependencies": {
         "glob": {
-          "version": "7.1.2",
-          "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.2.tgz",
-          "integrity": "sha512-MJTUg1kjuLeQCJ+ccE4Vpa6kKVXkPYJ2mOCQyUuKLcLQsdrMCpBPUi8qVE6+YuaJkozeA9NusTAw3hLr8Xe5EQ==",
+          "version": "7.1.6",
+          "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.6.tgz",
+          "integrity": "sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==",
           "dev": true,
           "requires": {
-            "fs.realpath": "1.0.0",
-            "inflight": "1.0.6",
-            "inherits": "2.0.3",
-            "minimatch": "3.0.4",
-            "once": "1.4.0",
-            "path-is-absolute": "1.0.1"
+            "fs.realpath": "^1.0.0",
+            "inflight": "^1.0.4",
+            "inherits": "2",
+            "minimatch": "^3.0.4",
+            "once": "^1.3.0",
+            "path-is-absolute": "^1.0.0"
           }
         }
       }
@@ -2972,7 +2864,7 @@
       "integrity": "sha1-yK1KXhEGYeQCp9IbUw4AnyX444k=",
       "dev": true,
       "requires": {
-        "once": "1.4.0"
+        "once": "^1.3.0"
       }
     },
     "rx-lite": {
@@ -2982,60 +2874,72 @@
       "dev": true
     },
     "safe-buffer": {
-      "version": "5.1.1",
-      "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.1.tgz",
-      "integrity": "sha512-kKvNJn6Mm93gAczWVJg7wH+wGYWNrDHdWvpUmHyEsgCtIwwo3bqPtV4tR5tuPaUhTOo/kvhVwd8XwwOllGYkbg=="
+      "version": "5.1.2",
+      "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.2.tgz",
+      "integrity": "sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g=="
+    },
+    "safer-buffer": {
+      "version": "2.1.2",
+      "resolved": "https://registry.npmjs.org/safer-buffer/-/safer-buffer-2.1.2.tgz",
+      "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==",
+      "dev": true
     },
     "semver": {
-      "version": "5.4.1",
-      "resolved": "https://registry.npmjs.org/semver/-/semver-5.4.1.tgz",
-      "integrity": "sha512-WfG/X9+oATh81XtllIo/I8gOiY9EXRdv1cQdyykeXK17YcUW3EXUAi2To4pcH6nZtJPr7ZOpM5OMyWJZm+8Rsg=="
+      "version": "5.7.1",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
+      "integrity": "sha512-sauaDf/PZdVgrLTNYHRtpXa1iRiKcaebiKQ1BJdpQlWH2lCvexQdX55snPFyK7QzpudqbCI0qXFfOasHdyNDGQ=="
     },
     "send": {
-      "version": "0.16.1",
-      "resolved": "https://registry.npmjs.org/send/-/send-0.16.1.tgz",
-      "integrity": "sha512-ElCLJdJIKPk6ux/Hocwhk7NFHpI3pVm/IZOYWqUmoxcgeyM+MpxHHKhb8QmlJDX1pU6WrgaHBkVNm73Sv7uc2A==",
+      "version": "0.17.1",
+      "resolved": "https://registry.npmjs.org/send/-/send-0.17.1.tgz",
+      "integrity": "sha512-BsVKsiGcQMFwT8UxypobUKyv7irCNRHk1T0G680vk88yf6LBByGcZJOTJCrTP2xVN6yI+XjPJcNuE3V4fT9sAg==",
       "dev": true,
       "requires": {
         "debug": "2.6.9",
-        "depd": "1.1.1",
-        "destroy": "1.0.4",
-        "encodeurl": "1.0.1",
-        "escape-html": "1.0.3",
-        "etag": "1.8.1",
+        "depd": "~1.1.2",
+        "destroy": "~1.0.4",
+        "encodeurl": "~1.0.2",
+        "escape-html": "~1.0.3",
+        "etag": "~1.8.1",
         "fresh": "0.5.2",
-        "http-errors": "1.6.2",
-        "mime": "1.4.1",
-        "ms": "2.0.0",
-        "on-finished": "2.3.0",
-        "range-parser": "1.2.0",
-        "statuses": "1.3.1"
+        "http-errors": "~1.7.2",
+        "mime": "1.6.0",
+        "ms": "2.1.1",
+        "on-finished": "~2.3.0",
+        "range-parser": "~1.2.1",
+        "statuses": "~1.5.0"
       },
       "dependencies": {
         "mime": {
-          "version": "1.4.1",
-          "resolved": "https://registry.npmjs.org/mime/-/mime-1.4.1.tgz",
-          "integrity": "sha512-KI1+qOZu5DcW6wayYHSzR/tXKCDC5Om4s1z2QJjDULzLcmf3DvzS7oluY4HCTrc+9FiKmWUgeNLg7W3uIQvxtQ==",
+          "version": "1.6.0",
+          "resolved": "https://registry.npmjs.org/mime/-/mime-1.6.0.tgz",
+          "integrity": "sha512-x0Vn8spI+wuJ1O6S7gnbaQg8Pxh4NNHb7KSINmEWKiPE4RKOplvijn+NkmYmmRgP68mc70j2EbeTFRsrswaQeg==",
+          "dev": true
+        },
+        "ms": {
+          "version": "2.1.1",
+          "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.1.tgz",
+          "integrity": "sha512-tgp+dl5cGk28utYktBsrFqA7HKgrhgPsg6Z/EfhWI4gl1Hwq8B/GmY/0oXZ6nF8hDVesS/FpnYaD/kOWhYQvyg==",
           "dev": true
         }
       }
     },
     "serve-static": {
-      "version": "1.13.1",
-      "resolved": "https://registry.npmjs.org/serve-static/-/serve-static-1.13.1.tgz",
-      "integrity": "sha512-hSMUZrsPa/I09VYFJwa627JJkNs0NrfL1Uzuup+GqHfToR2KcsXFymXSV90hoyw3M+msjFuQly+YzIH/q0MGlQ==",
+      "version": "1.14.1",
+      "resolved": "https://registry.npmjs.org/serve-static/-/serve-static-1.14.1.tgz",
+      "integrity": "sha512-JMrvUwE54emCYWlTI+hGrGv5I8dEwmco/00EvkzIIsR7MqrHonbD9pO2MOfFnpFntl7ecpZs+3mW+XbQZu9QCg==",
       "dev": true,
       "requires": {
-        "encodeurl": "1.0.1",
-        "escape-html": "1.0.3",
-        "parseurl": "1.3.2",
-        "send": "0.16.1"
+        "encodeurl": "~1.0.2",
+        "escape-html": "~1.0.3",
+        "parseurl": "~1.3.3",
+        "send": "0.17.1"
       }
     },
     "setprototypeof": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/setprototypeof/-/setprototypeof-1.1.0.tgz",
-      "integrity": "sha512-BvE/TwpZX4FXExxOxZyRGQQv651MSwmWKZGqvmPcRIjDqWub67kTKuIMx43cZZrS/cBBzwBcNDWoFxt2XEFIpQ==",
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/setprototypeof/-/setprototypeof-1.1.1.tgz",
+      "integrity": "sha512-JvdAWfbXeIGaZ9cILp38HntZSFSo3mWg6xGcJJsd+d4aRMOqauag1C63dJfDw7OaMYwEbHMOxEZ1lqVRYP2OAw==",
       "dev": true
     },
     "shelljs": {
@@ -3044,12 +2948,6 @@
       "integrity": "sha1-xUmCuZbHbvDB5rWfvcWCX1txMRM=",
       "dev": true
     },
-    "sigmund": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/sigmund/-/sigmund-1.0.1.tgz",
-      "integrity": "sha1-P/IfGYytIXX587eBhT/ZTQ0ZtZA=",
-      "dev": true
-    },
     "slash": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/slash/-/slash-1.0.0.tgz",
@@ -3074,7 +2972,7 @@
       "dev": true,
       "optional": true,
       "requires": {
-        "amdefine": "1.0.1"
+        "amdefine": ">=0.0.4"
       }
     },
     "source-map-support": {
@@ -3083,7 +2981,7 @@
       "integrity": "sha512-try0/JqxPLF9nOjvSta7tVondkP5dwgyLDjVoyMDlmjugT2lRZ1OfsrYTkCd2hkDnJTKRbO/Rl3orm8vlsUzbA==",
       "dev": true,
       "requires": {
-        "source-map": "0.5.7"
+        "source-map": "^0.5.6"
       },
       "dependencies": {
         "source-map": {
@@ -3101,9 +2999,9 @@
       "dev": true
     },
     "statuses": {
-      "version": "1.3.1",
-      "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.3.1.tgz",
-      "integrity": "sha1-+vUbnrdKrvOzrPStX2Gr8ky3uT4=",
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.5.0.tgz",
+      "integrity": "sha1-Fhx9rBd2Wf2YEfQ3cfqZOBR4Yow=",
       "dev": true
     },
     "string-width": {
@@ -3112,9 +3010,9 @@
       "integrity": "sha1-EYvfW4zcUaKn5w0hHgfisLmxB9M=",
       "dev": true,
       "requires": {
-        "code-point-at": "1.1.0",
-        "is-fullwidth-code-point": "1.0.0",
-        "strip-ansi": "3.0.1"
+        "code-point-at": "^1.0.0",
+        "is-fullwidth-code-point": "^1.0.0",
+        "strip-ansi": "^3.0.0"
       }
     },
     "string_decoder": {
@@ -3122,18 +3020,18 @@
       "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.0.3.tgz",
       "integrity": "sha512-4AH6Z5fzNNBcH+6XDMfA/BTt87skxqJlO0lAh3Dker5zThcAxG6mKz+iGu308UKoPPQ8Dcqx/4JhujzltRa+hQ==",
       "requires": {
-        "safe-buffer": "5.1.1"
+        "safe-buffer": "~5.1.0"
       }
     },
     "stringifier": {
-      "version": "1.3.0",
-      "resolved": "https://registry.npmjs.org/stringifier/-/stringifier-1.3.0.tgz",
-      "integrity": "sha1-3vGDQvaTPbDy2/yaoCF1tEjBeVk=",
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/stringifier/-/stringifier-1.4.0.tgz",
+      "integrity": "sha512-cNsMOqqrcbLcHTXEVmkw9y0fwDwkdgtZwlfyolzpQDoAE1xdNGhQhxBUfiDvvZIKl1hnUEgMv66nHwtMz3OjPw==",
       "dev": true,
       "requires": {
-        "core-js": "2.5.1",
-        "traverse": "0.6.6",
-        "type-name": "2.0.2"
+        "core-js": "^2.0.0",
+        "traverse": "^0.6.6",
+        "type-name": "^2.0.1"
       }
     },
     "strip-ansi": {
@@ -3142,7 +3040,7 @@
       "integrity": "sha1-ajhfuIU9lS1f8F0Oiq+UJ43GPc8=",
       "dev": true,
       "requires": {
-        "ansi-regex": "2.1.1"
+        "ansi-regex": "^2.0.0"
       }
     },
     "strip-json-comments": {
@@ -3163,12 +3061,12 @@
       "integrity": "sha1-K7xULw/amGGnVdOUf+/Ys/UThV8=",
       "dev": true,
       "requires": {
-        "ajv": "4.11.8",
-        "ajv-keywords": "1.5.1",
-        "chalk": "1.1.3",
-        "lodash": "4.17.10",
+        "ajv": "^4.7.0",
+        "ajv-keywords": "^1.0.0",
+        "chalk": "^1.1.1",
+        "lodash": "^4.0.0",
         "slice-ansi": "0.0.4",
-        "string-width": "2.1.1"
+        "string-width": "^2.0.0"
       },
       "dependencies": {
         "ansi-regex": {
@@ -3189,8 +3087,8 @@
           "integrity": "sha512-nOqH59deCq9SRHlxq1Aw85Jnt4w6KvLKqWVik6oA9ZklXLNIOlqg4F2yrT1MVaTjAqvVwdfeZ7w7aCvJD7ugkw==",
           "dev": true,
           "requires": {
-            "is-fullwidth-code-point": "2.0.0",
-            "strip-ansi": "4.0.0"
+            "is-fullwidth-code-point": "^2.0.0",
+            "strip-ansi": "^4.0.0"
           }
         },
         "strip-ansi": {
@@ -3199,7 +3097,7 @@
           "integrity": "sha1-qEeQIusaw2iocTibY1JixQXuNo8=",
           "dev": true,
           "requires": {
-            "ansi-regex": "3.0.0"
+            "ansi-regex": "^3.0.0"
           }
         }
       }
@@ -3210,9 +3108,9 @@
       "integrity": "sha1-btWic3ZPhu0mjJYeG9TVyk0N5tQ=",
       "dev": true,
       "requires": {
-        "express": "4.16.1",
-        "jade": "0.26.3",
-        "jasmine-node": "1.14.5"
+        "express": ">=2.5.0",
+        "jade": ">=0.18.0",
+        "jasmine-node": ">=1.0.0"
       }
     },
     "text-table": {
@@ -3233,6 +3131,12 @@
       "integrity": "sha1-uDVx+k2MJbguIxsG46MFXeTKGkc=",
       "dev": true
     },
+    "toidentifier": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/toidentifier/-/toidentifier-1.0.0.tgz",
+      "integrity": "sha512-yaOH/Pk/VEhBWWTlhI+qXxDFXlejDGcQipMlyxda9nthulaxLZUNcUqFxokp0vcYnvteJln5FNQDRrxj3YcbVw==",
+      "dev": true
+    },
     "traverse": {
       "version": "0.6.6",
       "resolved": "https://registry.npmjs.org/traverse/-/traverse-0.6.6.tgz",
@@ -3245,10 +3149,10 @@
       "integrity": "sha1-yy4SAwZ+DI3h9hQJS5/kVwTqYAM=",
       "dev": true
     },
-    "tryit": {
-      "version": "1.0.3",
-      "resolved": "https://registry.npmjs.org/tryit/-/tryit-1.0.3.tgz",
-      "integrity": "sha1-OTvnMKlEb9Hq1tpZoBQwjzbCics=",
+    "type": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/type/-/type-1.2.0.tgz",
+      "integrity": "sha512-+5nt5AAniqsCnu2cEQQdpzCAh33kVx8n0VoFidKpB1dVVLAN/F+bgVOqOJqOnEnrhp222clB5p3vUlD+1QAnfg==",
       "dev": true
     },
     "type-check": {
@@ -3257,17 +3161,17 @@
       "integrity": "sha1-WITKtRLPHTVeP7eE8wgEsrUg23I=",
       "dev": true,
       "requires": {
-        "prelude-ls": "1.1.2"
+        "prelude-ls": "~1.1.2"
       }
     },
     "type-is": {
-      "version": "1.6.15",
-      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.15.tgz",
-      "integrity": "sha1-yrEPtJCeRByChC6v4a1kbIGARBA=",
+      "version": "1.6.18",
+      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.18.tgz",
+      "integrity": "sha512-TkRKr9sUTxEH8MdfuCSP7VizJyzRNMjj2J2do2Jr3Kym598JVdEksuzPQCnlFPW4ky9Q+iA+ma9BGm06XQBy8g==",
       "dev": true,
       "requires": {
         "media-typer": "0.3.0",
-        "mime-types": "2.1.17"
+        "mime-types": "~2.1.24"
       }
     },
     "type-name": {
@@ -3288,10 +3192,10 @@
       "integrity": "sha1-8CHji6LKdAhg9b1caVwqgXNF8Ow=",
       "dev": true,
       "requires": {
-        "async": "0.2.10",
-        "source-map": "0.5.7",
-        "uglify-to-browserify": "1.0.2",
-        "yargs": "3.10.0"
+        "async": "~0.2.6",
+        "source-map": "~0.5.1",
+        "uglify-to-browserify": "~1.0.0",
+        "yargs": "~3.10.0"
       },
       "dependencies": {
         "async": {
@@ -3326,9 +3230,9 @@
       "integrity": "sha1-DaSsL3PP95JMgfpN4BjKViyisKc=",
       "dev": true,
       "requires": {
-        "array-filter": "1.0.0",
+        "array-filter": "^1.0.0",
         "indexof": "0.0.1",
-        "object-keys": "1.0.11"
+        "object-keys": "^1.0.0"
       }
     },
     "unpipe": {
@@ -3343,7 +3247,7 @@
       "integrity": "sha1-nHC/2Babwdy/SGBODwS4tJzenp8=",
       "dev": true,
       "requires": {
-        "os-homedir": "1.0.2"
+        "os-homedir": "^1.0.0"
       }
     },
     "util-deprecate": {
@@ -3388,12 +3292,12 @@
       "dev": true
     },
     "which": {
-      "version": "1.3.0",
-      "resolved": "https://registry.npmjs.org/which/-/which-1.3.0.tgz",
-      "integrity": "sha512-xcJpopdamTuY5duC/KnTTNBraPK54YwpenP4lzxU8H91GudWpFv38u0CKjclE1Wi2EH2EDz5LRcHcKbCIzqGyg==",
+      "version": "1.3.1",
+      "resolved": "https://registry.npmjs.org/which/-/which-1.3.1.tgz",
+      "integrity": "sha512-HxJdYWq1MTIQbJ3nw0cqssHoTNU267KlrDuGZ1WYlxDStUtKUhOaJmh112/TZmHxxUfuJqPXSOm7tDyas0OSIQ==",
       "dev": true,
       "requires": {
-        "isexe": "2.0.0"
+        "isexe": "^2.0.0"
       }
     },
     "window-size": {
@@ -3402,6 +3306,12 @@
       "integrity": "sha1-VDjNLqk7IC76Ohn+iIeu58lPnJ0=",
       "dev": true
     },
+    "word-wrap": {
+      "version": "1.2.3",
+      "resolved": "https://registry.npmjs.org/word-wrap/-/word-wrap-1.2.3.tgz",
+      "integrity": "sha512-Hz/mrNwitNRh/HUAtM/VT/5VH+ygD6DV7mYKZAtHOrbs8U7lvPS6xf7EJKMF0uW1KJCl0H701g3ZGus+muE5vQ==",
+      "dev": true
+    },
     "wordwrap": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-1.0.0.tgz",
@@ -3420,13 +3330,13 @@
       "integrity": "sha1-X8A4KOJkzqP+kUVUdvejxWbLB1c=",
       "dev": true,
       "requires": {
-        "mkdirp": "0.5.1"
+        "mkdirp": "^0.5.1"
       }
     },
     "xtend": {
-      "version": "4.0.1",
-      "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.1.tgz",
-      "integrity": "sha1-pcbVMr5lbiPbgg77lDofBJmNY68=",
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
+      "integrity": "sha512-LKYU1iAXJXUgAXn9URjiu+MWhyUXHsvfp7mcuYm9dSUKK0/CjtrUwFAxD82/mCWbtLsGjFIad0wIsod4zrTAEQ==",
       "dev": true
     },
     "yargs": {
@@ -3435,9 +3345,9 @@
       "integrity": "sha1-9+572FfdfB0tOMDnTvvWgdFDH9E=",
       "dev": true,
       "requires": {
-        "camelcase": "1.2.1",
-        "cliui": "2.1.0",
-        "decamelize": "1.2.0",
+        "camelcase": "^1.0.2",
+        "cliui": "^2.1.0",
+        "decamelize": "^1.0.0",
         "window-size": "0.1.0"
       }
     }
diff --git a/package.json b/package.json
index 82f996b592a..006b5373612 100644
--- a/package.json
+++ b/package.json
@@ -48,7 +48,6 @@
     "markdown": "0.5.0",
     "marked": "0.3.9",
     "mocha": "3.2.0",
-    "mongoose-long": "0.1.1",
     "mongodb-topology-manager": "1.0.11",
     "node-static": "0.7.7",
     "nsp": "~2.8.1",
diff --git a/test/model.update.test.js b/test/model.update.test.js
index a6a6fbd98b9..6da4b84f218 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -2230,26 +2230,6 @@ describe('model: update:', function() {
       });
     });
 
-    it('update handles casting with mongoose-long (gh-4283)', function(done) {
-      require('mongoose-long')(mongoose);
-
-      var Model = db.model('gh4283', {
-        number: { type: mongoose.Types.Long }
-      });
-
-      Model.create({ number: mongoose.mongo.Long.fromString('0') }, function(error) {
-        assert.ifError(error);
-        Model.update({}, { $inc: { number: mongoose.mongo.Long.fromString('2147483648') } }, function(error) {
-          assert.ifError(error);
-          Model.findOne({ number: { $type: 18 } }, function(error, doc) {
-            assert.ifError(error);
-            assert.ok(doc);
-            done();
-          });
-        });
-      });
-    });
-
     it('single nested with runValidators (gh-4420)', function(done) {
       var FileSchema = new Schema({
         name: String

From 8fa801277bc5c8d627c4af0dd4301d43e911a7af Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 22:25:40 -0500
Subject: [PATCH 0347/2348] test: test cleanup re: #8459

---
 test/schema.alias.test.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index a47bc44a018..75244842287 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -9,7 +9,7 @@ var start = require('./common'),
     Schema = mongoose.Schema;
 
 describe('schema alias option', function() {
-  it('works with all basic schema types', function() {
+  it('works with all basic schema types', function(done) {
     var db = start();
 
     var schema = new Schema({
@@ -45,10 +45,11 @@ describe('schema alias option', function() {
       assert.equal(s.mixed, s.MixedAlias);
       assert.equal(s.objectId, s.ObjectIdAlias);
       assert.equal(s.array, s.ArrayAlias);
+      done();
     });
   });
 
-  it('works with nested schema types', function() {
+  it('works with nested schema types', function(done) {
     var db = start();
 
     var schema = new Schema({
@@ -92,6 +93,8 @@ describe('schema alias option', function() {
       assert.equal(s.nested.mixed, s.MixedAlias);
       assert.equal(s.nested.objectId, s.ObjectIdAlias);
       assert.equal(s.nested.array, s.ArrayAlias);
+
+      done();
     });
   });
 

From 1db031cfa0f64e2eda8f4e428c530ea6dc201cd1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 22:32:57 -0500
Subject: [PATCH 0348/2348] test(schema): clean up messy tests re: #8459

---
 test/schema.alias.test.js | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index 75244842287..c2d7184d838 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -54,17 +54,14 @@ describe('schema alias option', function() {
 
     var schema = new Schema({
       nested: {
-        type: {
-          string:   { type: String, alias: 'StringAlias' },
-          number:   { type: Number, alias: 'NumberAlias' },
-          date:     { type: Date, alias: 'DateAlias' },
-          buffer:   { type: Buffer, alias: 'BufferAlias' },
-          boolean:  { type: Boolean, alias: 'BooleanAlias' },
-          mixed:    { type: Schema.Types.Mixed, alias: 'MixedAlias' },
-          objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias'},
-          array:    { type: [], alias: 'ArrayAlias' }
-        },
-        alias: 'NestedAlias'
+        string:   { type: String, alias: 'StringAlias' },
+        number:   { type: Number, alias: 'NumberAlias' },
+        date:     { type: Date, alias: 'DateAlias' },
+        buffer:   { type: Buffer, alias: 'BufferAlias' },
+        boolean:  { type: Boolean, alias: 'BooleanAlias' },
+        mixed:    { type: Schema.Types.Mixed, alias: 'MixedAlias' },
+        objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias'},
+        array:    { type: [], alias: 'ArrayAlias' }
       }
     });
 
@@ -84,7 +81,6 @@ describe('schema alias option', function() {
       assert.ifError(err);
 
       // Comparing with aliases
-      assert.equal(s.nested, s.NestedAlias);
       assert.equal(s.nested.string, s.StringAlias);
       assert.equal(s.nested.number, s.NumberAlias);
       assert.equal(s.nested.date, s.DateAlias);

From abb47f1beace122c3087a1535e91e63fdccda49a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Jan 2020 22:46:33 -0500
Subject: [PATCH 0349/2348] chore: release 5.8.6

---
 History.md   | 4 ++++
 package.json | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index b961240e0d1..d3e680a635e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,7 @@
+5.8.6 / 2020-01-07
+====================
+ * chore: merge changes from 4.13.20 and override mistaken publish to latest tag
+
 4.13.20 / 2020-01-07
 ====================
  * fix(schema): make aliases handle mongoose-lean-virtuals #6069
diff --git a/package.json b/package.json
index 6a28d64f39f..836c55db72a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.5",
+  "version": "5.8.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 56bbac4c6e93bb7bda0ddbf5a3351a9c48eb8db4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 9 Jan 2020 12:28:37 -0500
Subject: [PATCH 0350/2348] chore: now working on 5.8.7

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 836c55db72a..438c2fb8c95 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.6",
+  "version": "5.8.7-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b4b64864b40fef1473b632c32583ce7157b3cdba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 9 Jan 2020 12:28:43 -0500
Subject: [PATCH 0351/2348] docs(populate): improve cross-db populate docs to
 include model refs

Fix #8497
---
 docs/populate.pug | 54 +++++++++++++++++++++++++----------------------
 1 file changed, 29 insertions(+), 25 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 7fa462d8614..9681271c9cb 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -363,49 +363,53 @@ block content
       });
     ```
 
-    <h3 id="cross-db-populate"><a href="#cross-db-populate">Populating across Databases</a></h3>
+    <h3 id="cross-db-populate"><a href="#cross-db-populate">Cross Database Populate</a></h3>
 
     Let's say you have a schema representing events, and a schema representing
     conversations. Each event has a corresponding conversation thread.
 
     ```javascript
-    var eventSchema = new Schema({
+    const db1 = mongoose.createConnection('mongodb://localhost:27000/db1');
+    const db2 = mongoose.createConnection('mongodb://localhost:27001/db2');
+
+    const conversationSchema = new Schema({ numMessages: Number });
+    const Conversation = db2.model('Conversation', conversationSchema);
+
+    const eventSchema = new Schema({
       name: String,
-      // The id of the corresponding conversation
-      // Notice there's no ref here!
-      conversation: ObjectId
-    });
-    var conversationSchema = new Schema({
-      numMessages: Number
+      conversation: {
+        type: ObjectId,
+        ref: Conversation // `ref` is a **Model class**, not a string
+      }
     });
+    const Event = db1.model('Event', eventSchema);
     ```
 
-    Also, suppose that events and conversations are stored in separate MongoDB
-    instances.
+    In the above example, events and conversations are stored in separate MongoDB
+    databases. String `ref` will not work in this situation, because Mongoose
+    assumes a string `ref` refers to a model name on the same connection. In
+    the above example, the conversation model is registered on `db2`, not `db1`.
 
     ```javascript
-    var db1 = mongoose.createConnection('localhost:27000/db1');
-    var db2 = mongoose.createConnection('localhost:27001/db2');
-
-    var Event = db1.model('Event', eventSchema);
-    var Conversation = db2.model('Conversation', conversationSchema);
+    // Works
+    const events = await Event.
+      find().
+      populate('conversation');
     ```
 
-    In this situation, you will **not** be able to `populate()` normally.
-    The `conversation` field will always be null, because `populate()` doesn't
-    know which model to use. However,
-    [you can specify the model explicitly](./api.html#model_Model.populate).
+    This is known as a "cross-database populate," because it enables you to
+    populate across MongoDB databases and even across MongoDB instances.
+
+    If you don't have access to the model instance when defining your `eventSchema`,
+    you can also pass [the model instance as an option to `populate()`](/docs/api/model.html#model_Model.populate).
 
     ```javascript
-    Event.
+    const events = await Event.
       find().
-      populate({ path: 'conversation', model: Conversation }).
-      exec(function(error, docs) { /* ... */ });
+      // The `model` option specifies the model to use for populating.
+      populate({ path: 'conversation', model: Conversation });
     ```
 
-    This is known as a "cross-database populate," because it enables you to
-    populate across MongoDB databases and even across MongoDB instances.
-
     <h3 id="dynamic-ref"><a href="#dynamic-ref">Dynamic References via `refPath`</a></h3>
 
     Mongoose can also populate from multiple collections based on the value

From 7d92106f70e2f702cda2c4b5f0b02bfe64e45109 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 10 Jan 2020 04:37:50 +0200
Subject: [PATCH 0352/2348] Add support for default options per type

---
 lib/schema/string.js      | 12 ++++++++++++
 test/types.string.test.js | 29 +++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 test/types.string.test.js

diff --git a/lib/schema/string.js b/lib/schema/string.js
index 849e4e6083d..4fb70826919 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -25,6 +25,12 @@ let Document;
  */
 
 function SchemaString(key, options) {
+  const defaultOptionsKeys = Object.keys(SchemaString.defaultOptions);
+  for (const optionName of defaultOptionsKeys) {
+    if (SchemaString.defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
+      options[optionName] = SchemaString.defaultOptions[optionName];
+    }
+  }
   this.enumValues = [];
   this.regExp = null;
   SchemaType.call(this, key, options, 'String');
@@ -38,6 +44,12 @@ function SchemaString(key, options) {
  */
 SchemaString.schemaName = 'String';
 
+SchemaString.defaultOptions = {};
+
+SchemaString.setDefaultOption = function setDefaultOption(optionName,value) {
+  SchemaString.defaultOptions[optionName] = value;
+};
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/test/types.string.test.js b/test/types.string.test.js
new file mode 100644
index 00000000000..390fd184b0b
--- /dev/null
+++ b/test/types.string.test.js
@@ -0,0 +1,29 @@
+'use strict';
+
+/**
+ * Module dependencies.
+ */
+
+const mongoose = require('./common').mongoose;
+
+const assert = require('assert');
+
+/**
+ * Test.
+ */
+
+describe('types.string', function() {
+  describe('Schema.Types.String.setDefaultOptions(...)', function() {
+    it('when given an option, sets it', () => {
+      // Arrange
+      const mongooseInstance = new mongoose.Mongoose();
+
+      // Act
+      mongooseInstance.Schema.Types.String.setDefaultOption('trim',true);
+      const userSchema = new mongooseInstance.Schema({name:{type:String}});
+
+      // Assert
+      assert.equal(userSchema.path('name').options.trim, true);
+    });
+  });
+});

From 4286439b8e94d1eda4a46d6ede85cab283971f58 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 10 Jan 2020 06:06:17 +0200
Subject: [PATCH 0353/2348] [WIP] Fixes #8487

---
 lib/helpers/schematype/getDefaultOptionSetter.js |  8 ++++++++
 lib/schema/array.js                              |  4 ++++
 lib/schema/boolean.js                            |  4 ++++
 lib/schema/buffer.js                             |  4 ++++
 lib/schema/date.js                               |  4 ++++
 lib/schema/decimal128.js                         |  4 ++++
 lib/schema/map.js                                |  5 ++++-
 lib/schema/mixed.js                              |  4 ++++
 lib/schema/number.js                             |  4 ++++
 lib/schema/objectid.js                           |  4 ++++
 lib/schema/string.js                             | 12 ++----------
 lib/schematype.js                                | 10 ++++++++++
 12 files changed, 56 insertions(+), 11 deletions(-)
 create mode 100644 lib/helpers/schematype/getDefaultOptionSetter.js

diff --git a/lib/helpers/schematype/getDefaultOptionSetter.js b/lib/helpers/schematype/getDefaultOptionSetter.js
new file mode 100644
index 00000000000..9266c240a62
--- /dev/null
+++ b/lib/helpers/schematype/getDefaultOptionSetter.js
@@ -0,0 +1,8 @@
+'use strict';
+function getDefaultOptionSetter(type) {
+  return function setDefaultOption(optionName, value) {
+    type.defaultOptions[optionName] = value;
+  };
+}
+
+module.exports = getDefaultOptionSetter;
\ No newline at end of file
diff --git a/lib/schema/array.js b/lib/schema/array.js
index e32cff9bfc5..74d2d829fa1 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -18,6 +18,7 @@ const utils = require('../utils');
 const castToNumber = require('./operators/helpers').castToNumber;
 const geospatial = require('./operators/geospatial');
 const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminatorByValue');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let MongooseArray;
 let EmbeddedDoc;
@@ -121,6 +122,9 @@ function SchemaArray(key, cast, options, schemaOptions) {
  */
 SchemaArray.schemaName = 'Array';
 
+SchemaArray.defaultOptions = {};
+SchemaArray.setDefaultOption = getDefaultOptionSetter(SchemaArray);
+
 /**
  * Options for all arrays.
  *
diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 13d796c45f8..86804dbd8c5 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -8,6 +8,7 @@ const CastError = require('../error/cast');
 const SchemaType = require('../schematype');
 const castBoolean = require('../cast/boolean');
 const utils = require('../utils');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Boolean SchemaType constructor.
@@ -30,6 +31,9 @@ function SchemaBoolean(path, options) {
  */
 SchemaBoolean.schemaName = 'Boolean';
 
+SchemaBoolean.defaultOptions = {};
+SchemaBoolean.setDefaultOption = getDefaultOptionSetter(SchemaBoolean);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 91edf2aaf71..b75328add28 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -11,6 +11,7 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const Binary = MongooseBuffer.Binary;
 const CastError = SchemaType.CastError;
@@ -37,6 +38,9 @@ function SchemaBuffer(key, options) {
  */
 SchemaBuffer.schemaName = 'Buffer';
 
+SchemaBuffer.defaultOptions = {};
+SchemaBuffer.setDefaultOption = getDefaultOptionSetter(SchemaBuffer);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/date.js b/lib/schema/date.js
index 3c9b9146f33..dd1849590db 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -9,6 +9,7 @@ const SchemaDateOptions = require('../options/SchemaDateOptions');
 const SchemaType = require('../schematype');
 const castDate = require('../cast/date');
 const utils = require('../utils');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 
@@ -33,6 +34,9 @@ function SchemaDate(key, options) {
  */
 SchemaDate.schemaName = 'Date';
 
+SchemaDate.defaultOptions = {};
+SchemaDate.setDefaultOption = getDefaultOptionSetter(SchemaDate);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index 0978d47b267..0520d2c0cc2 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -11,6 +11,7 @@ const castDecimal128 = require('../cast/decimal128');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let Document;
 
@@ -35,6 +36,9 @@ function Decimal128(key, options) {
  */
 Decimal128.schemaName = 'Decimal128';
 
+Decimal128.defaultOptions = {};
+Decimal128.setDefaultOption = getDefaultOptionSetter(Decimal128);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/map.js b/lib/schema/map.js
index 14fd248e832..ee3b946a397 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -7,7 +7,7 @@
 const MongooseMap = require('../types/map');
 const SchemaMapOptions = require('../options/SchemaMapOptions');
 const SchemaType = require('../schematype');
-
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 /*!
  * ignore
  */
@@ -17,6 +17,9 @@ class Map extends SchemaType {
     super(key, options, 'Map');
     this.$isSchemaMap = true;
   }
+  static setDefaultOption() {
+    return getDefaultOptionSetter(Map);
+  }
 
   cast(val, doc, init) {
     if (val instanceof MongooseMap) {
diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 672cc519167..36316f37a97 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -7,6 +7,7 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const utils = require('../utils');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Mixed SchemaType constructor.
@@ -44,6 +45,9 @@ function Mixed(path, options) {
  */
 Mixed.schemaName = 'Mixed';
 
+Mixed.defaultOptions = {};
+Mixed.setDefaultOption = getDefaultOptionSetter(Mixed);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/number.js b/lib/schema/number.js
index e32ae2b4237..47158c9d16d 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -12,6 +12,7 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -102,6 +103,9 @@ SchemaNumber.cast = function cast(caster) {
  */
 SchemaNumber.schemaName = 'Number';
 
+SchemaNumber.defaultOptions = {};
+SchemaNumber.setDefaultOption = getDefaultOptionSetter(SchemaNumber);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index 761ebd1df4a..bba8e62873b 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -11,6 +11,7 @@ const oid = require('../types/objectid');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -45,6 +46,9 @@ function ObjectId(key, options) {
  */
 ObjectId.schemaName = 'ObjectId';
 
+ObjectId.defaultOptions = {};
+ObjectId.setDefaultOption = getDefaultOptionSetter(ObjectId);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 4fb70826919..17a5ce8c715 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -11,6 +11,7 @@ const castString = require('../cast/string');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -25,12 +26,6 @@ let Document;
  */
 
 function SchemaString(key, options) {
-  const defaultOptionsKeys = Object.keys(SchemaString.defaultOptions);
-  for (const optionName of defaultOptionsKeys) {
-    if (SchemaString.defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
-      options[optionName] = SchemaString.defaultOptions[optionName];
-    }
-  }
   this.enumValues = [];
   this.regExp = null;
   SchemaType.call(this, key, options, 'String');
@@ -45,10 +40,7 @@ function SchemaString(key, options) {
 SchemaString.schemaName = 'String';
 
 SchemaString.defaultOptions = {};
-
-SchemaString.setDefaultOption = function setDefaultOption(optionName,value) {
-  SchemaString.defaultOptions[optionName] = value;
-};
+SchemaString.setDefaultOption = getDefaultOptionSetter(SchemaString);
 
 /*!
  * Inherits from SchemaType.
diff --git a/lib/schematype.js b/lib/schematype.js
index f5bda24f89e..9466ef25388 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -44,6 +44,16 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
+  const defaultOptions = this.constructor.defaultOptions;
+  const defaultOptionsKeys = Object.keys(defaultOptions);
+
+  for (const optionName of defaultOptionsKeys) {
+    if (defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
+      options[optionName] = defaultOptions[optionName];
+    }
+  }
+
+
   const Options = this.OptionsConstructor || SchemaTypeOptions;
   this.options = new Options(options);
   this._index = null;

From a7cd798fb4308d6a7b4c5a0356c5eedca8575781 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 10 Jan 2020 06:09:35 +0200
Subject: [PATCH 0354/2348] Add fallback to empty object for default options

---
 lib/schematype.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index 9466ef25388..305ba3a6c55 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -44,7 +44,7 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
-  const defaultOptions = this.constructor.defaultOptions;
+  const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
 
   for (const optionName of defaultOptionsKeys) {

From a3ab3a65d361eff6e39ef79dcdbd3ac7a11de5b1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 15:26:52 -0500
Subject: [PATCH 0355/2348] test(document): repro #8482

---
 test/types.array.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/types.array.test.js b/test/types.array.test.js
index fe87c82eeaa..cc4757cc458 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1653,6 +1653,20 @@ describe('types array', function() {
     });
   });
 
+  describe('slice', function() {
+    it('copies schema correctly (gh-8482)', function() {
+      const M = db.model('Test', Schema({ arr: [Number] }));
+
+      const doc = new M({ arr: [1, 2, 3] });
+
+      let arr = doc.arr.slice(2);
+
+      arr.splice(1, 0, 5, 7, 11);
+
+      assert.deepEqual(arr, [3, 5, 7, 11]);
+    });
+  });
+
   describe('setting a doc array', function() {
     it('should adjust path positions', function(done) {
       const D = db.model('subDocPositions', new Schema({

From a041b440861fb2c02e7f5fd94cd7ae31826fb18a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 15:27:40 -0500
Subject: [PATCH 0356/2348] fix(document): ensure that you can call `splice()`
 after `slice()` on an array

Fix #8482
---
 lib/types/core_array.js | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index dd587534707..80b2026a227 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -808,12 +808,18 @@ class CoreMongooseArray extends Array {
     _checkManualPopulation(this, Array.prototype.slice.call(arguments, 2));
 
     if (arguments.length) {
-      const vals = [];
-      for (let i = 0; i < arguments.length; ++i) {
-        vals[i] = i < 2 ?
-          arguments[i] :
-          this._cast(arguments[i], arguments[0] + (i - 2));
+      let vals;
+      if (this[arraySchemaSymbol] == null) {
+        vals = arguments;
+      } else {
+        vals = [];
+        for (let i = 0; i < arguments.length; ++i) {
+          vals[i] = i < 2 ?
+            arguments[i] :
+            this._cast(arguments[i], arguments[0] + (i - 2));
+        }
       }
+
       ret = [].splice.apply(this, vals);
       this._registerAtomic('$set', this);
     }

From b2f2bdf0f0b4d27e850ae2da2e0e909e22f34312 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 16:17:57 -0500
Subject: [PATCH 0357/2348] test(documentarray): repro #8479

---
 test/types.array.test.js         |  2 +-
 test/types.documentarray.test.js | 27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/test/types.array.test.js b/test/types.array.test.js
index cc4757cc458..4e5ae89dced 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1659,7 +1659,7 @@ describe('types array', function() {
 
       const doc = new M({ arr: [1, 2, 3] });
 
-      let arr = doc.arr.slice(2);
+      const arr = doc.arr.slice(2);
 
       arr.splice(1, 0, 5, 7, 11);
 
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 31201d00b29..e51d4d95492 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -640,4 +640,31 @@ describe('types.documentarray', function() {
       assert.deepEqual(parent.toObject().children, [{ name: '3' }]);
     });
   });
+
+  it('modifies ownerDocument() on set (gh-8479)', function() {
+    const nestedArraySchema = Schema({
+      name: String,
+      subDocArray: [{ name: String }]
+    });
+
+    const Model = db.model('Test', nestedArraySchema);
+
+    const doc1 = new Model({
+      name: 'doc1',
+      subDocArray: [{
+        name: 'subDoc'
+      }]
+    });
+    const doc2 = new Model({
+      name: 'doc2',
+      subDocArray: [{
+        name: 'subDoc'
+      }]
+    });
+
+    doc1.subDocArray = doc2.subDocArray;
+
+    assert.equal(doc2.subDocArray[0].ownerDocument().name, 'doc2');
+    assert.equal(doc1.subDocArray[0].ownerDocument().name, 'doc1');
+  });
 });

From d938e9a610f82946ee8af5c4c6040e51e451e5c0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 16:19:18 -0500
Subject: [PATCH 0358/2348] fix(documentarray): modify ownerDocument when
 setting doc array to a doc array thats part of another document

Fix #8479
---
 test/document.test.js | 192 +++++++++++++++++++++++-------------------
 1 file changed, 107 insertions(+), 85 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index f4f189144ee..2589bdb86e2 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -132,6 +132,21 @@ describe('document', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => {
+    const arr = [];
+
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
   describe('constructor', function() {
     it('supports passing in schema directly (gh-8237)', function() {
       const myUserDoc = new Document({}, { name: String });
@@ -146,7 +161,7 @@ describe('document', function() {
   describe('delete', function() {
     it('deletes the document', function() {
       const schema = new Schema({ x: String });
-      const Test = db.model('gh6940', schema);
+      const Test = db.model('Test', schema);
       return co(function* () {
         const test = new Test({ x: 'test' });
         const doc = yield test.save();
@@ -162,7 +177,8 @@ describe('document', function() {
 
     before(function() {
       const schema = new Schema({ x: String, y: String });
-      Test = db.model('gh6940_2', schema);
+      db.deleteModel(/^Test$/);
+      Test = db.model('Test', schema);
     });
 
     it('updates the document', function() {
@@ -187,7 +203,7 @@ describe('document', function() {
         docs.push(doc);
         next();
       });
-      const Model = db.model('gh8262', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         const doc = yield Model.create({ x: 2, y: 4 });
@@ -202,7 +218,7 @@ describe('document', function() {
   describe('replaceOne', function() {
     it('replaces the document', function() {
       const schema = new Schema({ x: String });
-      const Test = db.model('gh6940_3', schema);
+      const Test = db.model('Test', schema);
       return co(function* () {
         const test = new Test({ x: 'test' });
         const doc = yield test.save();
@@ -499,7 +515,7 @@ describe('document', function() {
   it('toObject transform', function(done) {
     const schema = new Schema({
       name: String,
-      places: [{type: ObjectId, ref: 'toObject-transform-places'}]
+      places: [{type: ObjectId, ref: 'Place'}]
     });
 
     const schemaPlaces = new Schema({
@@ -508,14 +524,13 @@ describe('document', function() {
 
     schemaPlaces.set('toObject', {
       transform: function(doc, ret) {
-        // here should be only toObject-transform-places documents
-        assert.equal(doc.constructor.modelName, 'toObject-transform-places');
+        assert.equal(doc.constructor.modelName, 'Place');
         return ret;
       }
     });
 
-    const Test = db.model('toObject-transform', schema);
-    const Places = db.model('toObject-transform-places', schemaPlaces);
+    const Test = db.model('Test', schema);
+    const Places = db.model('Place', schemaPlaces);
 
     Places.create({identity: 'a'}, {identity: 'b'}, {identity: 'c'}, function(err, a, b, c) {
       Test.create({name: 'chetverikov', places: [a, b, c]}, function(err) {
@@ -541,7 +556,7 @@ describe('document', function() {
     });
     schema.virtual('answer').get(() => 42);
 
-    const Model = db.model('gh7548', schema);
+    const Model = db.model('Person', schema);
 
     const doc = new Model({ name: 'Jean-Luc Picard', age: 59 });
 
@@ -556,7 +571,7 @@ describe('document', function() {
 
   it('saves even if `_id` is null (gh-6406)', function() {
     const schema = new Schema({ _id: Number, val: String });
-    const Model = db.model('gh6406', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.updateOne({ _id: null }, { val: 'test' }, { upsert: true });
@@ -576,7 +591,7 @@ describe('document', function() {
 
   it('allows you to skip validation on save (gh-2981)', function() {
     const schema = new Schema({ name: { type: String, required: true } });
-    const MyModel = db.model('gh2981', schema);
+    const MyModel = db.model('Test', schema);
 
     const doc = new MyModel();
     return doc.save({ validateBeforeSave: false });
@@ -599,7 +614,7 @@ describe('document', function() {
         return ret;
       }
     });
-    const Test = db.model('TestToObject', schema);
+    const Test = db.model('Test', schema);
 
     Test.create({name: 'chetverikov', iWillNotBeDelete: true, 'nested.iWillNotBeDeleteToo': true}, function(err) {
       assert.ifError(err);
@@ -632,7 +647,7 @@ describe('document', function() {
         sub: [subdocSchema]
       });
 
-      const Doc = db.model('Doc', docSchema);
+      const Doc = db.model('Test', docSchema);
 
       Doc.create({
         foo: 'someString',
@@ -678,7 +693,7 @@ describe('document', function() {
         }
       };
 
-      const Topic = db.model('gh2691', topicSchema, 'gh2691');
+      const Topic = db.model('Test', topicSchema);
 
       const topic = new Topic({
         title: 'Favorite Foods',
@@ -708,7 +723,7 @@ describe('document', function() {
       userSchema.set('toObject', {virtuals: false});
 
       const postSchema = new Schema({
-        owner: {type: Schema.Types.ObjectId, ref: 'gh-2035-user'},
+        owner: {type: Schema.Types.ObjectId, ref: 'User'},
         content: String
       });
 
@@ -717,8 +732,8 @@ describe('document', function() {
       });
 
       postSchema.set('toObject', {virtuals: true});
-      const User = db.model('gh-2035-user', userSchema, 'gh-2035-user');
-      const Post = db.model('gh-2035-post', postSchema, 'gh-2035-post');
+      const User = db.model('User', userSchema);
+      const Post = db.model('Post', postSchema);
 
       const user = new User({firstName: 'Joe', lastName: 'Smith', password: 'password'});
 
@@ -888,14 +903,14 @@ describe('document', function() {
       userSchema.virtual('hello').get(function() {
         return 'Hello, ' + this.name;
       });
-      const User = db.model('gh1376_User', userSchema);
+      const User = db.model('User', userSchema);
 
       const groupSchema = new Schema({
         name: String,
-        _users: [{type: Schema.ObjectId, ref: 'gh1376_User'}]
+        _users: [{type: Schema.ObjectId, ref: 'User'}]
       });
 
-      const Group = db.model('gh1376_Group', groupSchema);
+      const Group = db.model('Group', groupSchema);
 
       User.create({name: 'Alice'}, {name: 'Bob'}, function(err, alice, bob) {
         assert.ifError(err);
@@ -932,7 +947,7 @@ describe('document', function() {
           this.name = title;
         });
 
-      const Task = db.model('gh4001', taskSchema);
+      const Task = db.model('Test', taskSchema);
 
       const doc = { name: 'task1', title: 'task999' };
       Task.collection.insertOne(doc, function(error) {
@@ -954,7 +969,7 @@ describe('document', function() {
         title: String,
         postedBy: {
           type: mongoose.Schema.Types.ObjectId,
-          ref: 'gh4213'
+          ref: 'User'
         }
       }, {
         toObject: {
@@ -969,8 +984,8 @@ describe('document', function() {
         }
       });
 
-      const User = db.model('gh4213', UserSchema);
-      const Post = db.model('gh4213_0', PostSchema);
+      const User = db.model('User', UserSchema);
+      const Post = db.model('Post', PostSchema);
 
       const val = new User({ name: 'Val' });
       const post = new Post({ title: 'Test', postedBy: val._id });
@@ -993,15 +1008,15 @@ describe('document', function() {
 
     it('populate on nested path (gh-5703)', function() {
       const toySchema = new mongoose.Schema({ color: String });
-      const Toy = db.model('gh5703', toySchema);
+      const Toy = db.model('Toy', toySchema);
 
       const childSchema = new mongoose.Schema({
         name: String,
         values: {
-          toy: { type: mongoose.Schema.Types.ObjectId, ref: 'gh5703' }
+          toy: { type: mongoose.Schema.Types.ObjectId, ref: 'Toy' }
         }
       });
-      const Child = db.model('gh5703_0', childSchema);
+      const Child = db.model('Child', childSchema);
 
       return Toy.create({ color: 'blue' }).
         then(function(toy) {
@@ -1024,14 +1039,14 @@ describe('document', function() {
   describe.skip('#update', function() {
     it('returns a Query', function(done) {
       const mg = new mongoose.Mongoose;
-      const M = mg.model('doc#update', {s: String});
+      const M = mg.model('Test', {s: String});
       const doc = new M;
       assert.ok(doc.update() instanceof Query);
       done();
     });
     it('calling update on document should relay to its model (gh-794)', function(done) {
       const Docs = new Schema({text: String});
-      const docs = db.model('docRelayUpdate', Docs);
+      const docs = db.model('Test', Docs);
       const d = new docs({text: 'A doc'});
       let called = false;
       d.save(function() {
@@ -1089,9 +1104,9 @@ describe('document', function() {
       return 10;
     };
 
-    const E = db.model('EmbeddedMethodsAndStaticsE', ESchema);
+    const E = db.model('Test', ESchema);
     const PSchema = new Schema({embed: [ESchema]});
-    const P = db.model('EmbeddedMethodsAndStaticsP', PSchema);
+    const P = db.model('Test2', PSchema);
 
     let p = new P({embed: [{name: 'peanut'}]});
     assert.equal(typeof p.embed[0].test, 'function');
@@ -1143,7 +1158,7 @@ describe('document', function() {
       embed11: [new Schema({name: String})]
     });
 
-    const S = db.model('noMaxListeners', schema);
+    const S = db.model('Test', schema);
 
     new S({title: 'test'});
     assert.equal(traced, false);
@@ -1155,7 +1170,7 @@ describe('document', function() {
       name: String,
       req: {type: String, required: true}
     });
-    const T = db.model('unselectedRequiredFieldValidation', Tschema);
+    const T = db.model('Test', Tschema);
 
     const t = new T({name: 'teeee', req: 'i am required'});
     t.save(function(err) {
@@ -1210,7 +1225,7 @@ describe('document', function() {
         nick: {type: String, required: true}
       });
 
-      const M = db.model('validateSchema', schema, collection);
+      const M = db.model('Test', schema, collection);
       const m = new M({prop: 'gh891', nick: 'validation test'});
       m.save(function(err) {
         assert.ifError(err);
@@ -1241,7 +1256,7 @@ describe('document', function() {
         nick: {type: String, required: true}
       });
 
-      const M = db.model('validateSchemaPromise', schema, collection);
+      const M = db.model('Test', schema);
       const m = new M({prop: 'gh891', nick: 'validation test'});
       const mBad = new M({prop: 'other'});
 
@@ -1263,7 +1278,7 @@ describe('document', function() {
 
     it('doesnt have stale cast errors (gh-2766)', function(done) {
       const testSchema = new Schema({name: String});
-      const M = db.model('gh2766', testSchema);
+      const M = db.model('Test', testSchema);
 
       const m = new M({_id: 'this is not a valid _id'});
       assert.ok(!m.$isValid('_id'));
@@ -1281,7 +1296,7 @@ describe('document', function() {
     it('cast errors persist across validate() calls (gh-2766)', function(done) {
       const db = start();
       const testSchema = new Schema({name: String});
-      const M = db.model('gh2766', testSchema);
+      const M = db.model('Test', testSchema);
 
       const m = new M({_id: 'this is not a valid _id'});
       assert.ok(!m.$isValid('_id'));
@@ -1306,7 +1321,7 @@ describe('document', function() {
 
       schema = new Schema({_id: String});
 
-      const M = db.model('validateSchemaPromise2', schema, collection);
+      const M = db.model('Test', schema);
       const m = new M();
 
       const promise = m.validate();
@@ -1327,7 +1342,7 @@ describe('document', function() {
           name: String,
           arr: {type: [], required: true}
         });
-        const M = db.model('validateSchema-array1', schema, collection);
+        const M = db.model('Test', schema);
         const m = new M({name: 'gh1109-1', arr: null});
         m.save(function(err) {
           assert.ok(/Path `arr` is required/.test(err));
@@ -1358,7 +1373,7 @@ describe('document', function() {
           arr: {type: [], validate: validate}
         });
 
-        const M = db.model('validateSchema-array2', schema, collection);
+        const M = db.model('Test', schema);
         const m = new M({name: 'gh1109-2', arr: [1]});
         assert.equal(called, false);
         m.save(function(err) {
@@ -1385,7 +1400,7 @@ describe('document', function() {
           arr: {type: [], required: true, validate: validate}
         });
 
-        const M = db.model('validateSchema-array3', schema, collection);
+        const M = db.model('Test', schema, collection);
         const m = new M({name: 'gh1109-3', arr: null});
         m.save(function(err) {
           assert.equal(err.errors.arr.message, 'Path `arr` is required.');
@@ -1418,7 +1433,7 @@ describe('document', function() {
         controls: [Control]
       });
 
-      const Post = db.model('post', PostSchema);
+      const Post = db.model('Post', PostSchema);
 
       const post = new Post({
         controls: [{
@@ -1451,7 +1466,7 @@ describe('document', function() {
         controls: [Control]
       });
 
-      const Post = db.model('post', PostSchema);
+      const Post = db.model('Post', PostSchema);
 
       const post = new Post({
         controls: [{
@@ -1488,7 +1503,7 @@ describe('document', function() {
         }
       });
 
-      const MWSV = db.model('mwv', new Schema({subs: [SchemaWithValidator]}));
+      const MWSV = db.model('Test', new Schema({subs: [SchemaWithValidator]}));
       const m = new MWSV({
         subs: [{
           preference: 'xx'
@@ -1518,9 +1533,7 @@ describe('document', function() {
     InvalidateSchema = new Schema({prop: {type: String}},
       {strict: false});
 
-    mongoose.model('InvalidateSchema', InvalidateSchema);
-
-    Post = db.model('InvalidateSchema');
+    Post = db.model('Test', InvalidateSchema);
     post = new Post();
     post.set({baz: 'val'});
     const _err = post.invalidate('baz', 'validation failed for path {PATH}',
@@ -1552,11 +1565,12 @@ describe('document', function() {
       let M;
 
       before(function() {
-        S = db.model('equals-S', new Schema({_id: String}));
-        N = db.model('equals-N', new Schema({_id: Number}));
-        O = db.model('equals-O', new Schema({_id: Schema.ObjectId}));
-        B = db.model('equals-B', new Schema({_id: Buffer}));
-        M = db.model('equals-I', new Schema({name: String}, {_id: false}));
+        db.deleteModel(/^Test/);
+        S = db.model('Test', new Schema({_id: String}));
+        N = db.model('Test2', new Schema({_id: Number}));
+        O = db.model('Test3', new Schema({_id: Schema.ObjectId}));
+        B = db.model('Test4', new Schema({_id: Buffer}));
+        M = db.model('Test5', new Schema({name: String}, {_id: false}));
       });
 
       it('with string _ids', function(done) {
@@ -1780,7 +1794,7 @@ describe('document', function() {
           val = v;
         });
 
-        M = db.model('gh-1154', schema);
+        M = db.model('Test', schema);
         done();
       });
 
@@ -1820,7 +1834,7 @@ describe('document', function() {
           doc.name.first = parts.slice(0, parts.length - 1).join(' ');
           doc.name.last = parts[parts.length - 1];
         });
-      const Model = db.model('gh4143', schema);
+      const Model = db.model('Person', schema);
 
       const doc = new Model({ name: { first: 'Jean-Luc', last: 'Picard' } });
       assert.equal(doc.fullname, 'Jean-Luc Picard');
@@ -1833,7 +1847,7 @@ describe('document', function() {
 
   describe('gh-2082', function() {
     it('works', function(done) {
-      const Parent = db.model('gh2082', parentSchema, 'gh2082');
+      const Parent = db.model('Test', parentSchema);
 
       const parent = new Parent({name: 'Hello'});
       parent.save(function(err, parent) {
@@ -1861,7 +1875,7 @@ describe('document', function() {
 
   describe('gh-1933', function() {
     it('works', function(done) {
-      const M = db.model('gh1933', new Schema({id: String, field: Number}), 'gh1933');
+      const M = db.model('Test', new Schema({id: String, field: Number}));
 
       M.create({}, function(error) {
         assert.ifError(error);
@@ -1888,8 +1902,8 @@ describe('document', function() {
         children: [ItemChildSchema]
       });
 
-      const ItemParent = db.model('gh-1638-1', ItemParentSchema, 'gh-1638-1');
-      const ItemChild = db.model('gh-1638-2', ItemChildSchema, 'gh-1638-2');
+      const ItemParent = db.model('Parent', ItemParentSchema);
+      const ItemChild = db.model('Child', ItemChildSchema);
 
       const c1 = new ItemChild({name: 'first child'});
       const c2 = new ItemChild({name: 'second child'});
@@ -1919,7 +1933,7 @@ describe('document', function() {
         s: []
       });
 
-      const Item = db.model('gh-2434', ItemSchema, 'gh-2434');
+      const Item = db.model('Test', ItemSchema);
 
       const item = new Item({st: 1});
 
@@ -1941,10 +1955,18 @@ describe('document', function() {
   });
 
   describe('gh-8371', function() {
+    beforeEach(() => co(function*() {
+      const Person = db.model('Person', Schema({ name: String }));
+
+      yield Person.deleteMany({});
+
+      db.deleteModel('Person');
+    }));
+
     it('setting isNew to true makes save tries to insert a new document (gh-8371)', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
-        const Person = db.model('gh8371-A', personSchema);
+        const Person = db.model('Person', personSchema);
 
         const createdPerson = yield Person.create({name:'Hafez'});
         const removedPerson = yield Person.findOneAndRemove({_id:createdPerson._id});
@@ -1961,7 +1983,7 @@ describe('document', function() {
     it('setting isNew to true throws an error when a document already exists (gh-8371)', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
-        const Person = db.model('gh8371-B', personSchema);
+        const Person = db.model('Person', personSchema);
 
         const createdPerson = yield Person.create({name:'Hafez'});
 
@@ -1983,7 +2005,7 @@ describe('document', function() {
     it('saving a document with no changes, throws an error when document is not found', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
-        const Person = db.model('gh8371-C', personSchema);
+        const Person = db.model('Person', personSchema);
 
         const person = yield Person.create({name:'Hafez'});
 
@@ -1995,7 +2017,7 @@ describe('document', function() {
         }
         catch (err) {
           assert.equal(err instanceof DocumentNotFoundError, true);
-          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-C"`);
+          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "Person"`);
           threw = true;
         }
 
@@ -2006,7 +2028,7 @@ describe('document', function() {
     it('saving a document with changes, throws an error when document is not found', function() {
       return co(function*() {
         const personSchema = new Schema({ name: String });
-        const Person = db.model('gh8371-D', personSchema);
+        const Person = db.model('Person', personSchema);
 
         const person = yield Person.create({name:'Hafez'});
 
@@ -2020,7 +2042,7 @@ describe('document', function() {
         }
         catch (err) {
           assert.equal(err instanceof DocumentNotFoundError,true);
-          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "gh8371-D"`);
+          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "Person"`);
           threw = true;
         }
 
@@ -2040,7 +2062,7 @@ describe('document', function() {
     };
     personSchema.queue('fn');
 
-    const Person = db.model('gh2856', personSchema, 'gh2856');
+    const Person = db.model('Person', personSchema);
     new Person({name: 'Val'});
     assert.equal(calledName, 'Val');
     done();
@@ -2072,8 +2094,8 @@ describe('document', function() {
         }
       };
 
-      const Child = db.model('gh-2910-1', childSchema);
-      const Parent = db.model('gh-2910-0', parentSchema);
+      const Child = db.model('Child', childSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Child.create({name: 'test'}, function(error, c) {
         Parent.create({c: c._id}, function(error, p) {
@@ -2119,7 +2141,7 @@ describe('document', function() {
       const topLevelSchema = new Schema({
         embedded: embeddedSchema
       });
-      const MyModel = db.model('gh5807', topLevelSchema);
+      const MyModel = db.model('Test', topLevelSchema);
 
       return MyModel.create({}).
         then(function(doc) {
@@ -2229,7 +2251,7 @@ describe('document', function() {
         next();
       });
 
-      const Event = db.model('gh2689', eventSchema);
+      const Event = db.model('Event', eventSchema);
 
       const e = new Event({name: 'test', user: {name: 123, email: 'val'}});
       e.save(function(error) {
@@ -2262,7 +2284,7 @@ describe('document', function() {
         name: String
       });
 
-      const Event = db.model('gh2689_1', eventSchema);
+      const Event = db.model('Event', eventSchema);
 
       const e = new Event({name: 'test', user: {}});
       let error = e.validateSync();
@@ -2291,7 +2313,7 @@ describe('document', function() {
         name: String
       });
 
-      const Event = db.model('gh5134', eventSchema);
+      const Event = db.model('Event', eventSchema);
 
       const e = new Event({name: 'test', user: {}});
       assert.strictEqual(e.user.parent(), e.user.ownerDocument());
@@ -2310,7 +2332,7 @@ describe('document', function() {
         name: String
       });
 
-      const Event = db.model('gh2689_2', eventSchema);
+      const Event = db.model('Event', eventSchema);
 
       const e = new Event({name: 'test', user: {email: 'a@b'}});
       e.save(function(error, doc) {
@@ -2351,7 +2373,7 @@ describe('document', function() {
         name: String
       });
 
-      const Event = db.model('gh2689_3', eventSchema);
+      const Event = db.model('Event', eventSchema);
 
       const badUpdate = {$set: {'user.email': 'a'}};
       const options = {runValidators: true};
@@ -2381,7 +2403,7 @@ describe('document', function() {
           test: String
         });
 
-        const Model = db.model('gh6269', schema);
+        const Model = db.model('Test', schema);
 
         const fakeDoc = new Model({});
         yield Model.create({});
@@ -2434,7 +2456,7 @@ describe('document', function() {
         next(error);
       });
 
-      const Test = db.model('gh4885', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create({}, function(error) {
         assert.ok(error);
@@ -2446,7 +2468,7 @@ describe('document', function() {
     it('does not filter validation on unmodified paths when validateModifiedOnly not set (gh-7421)', function(done) {
       const testSchema = new Schema({ title: { type: String, required: true }, other: String });
 
-      const Test = db.model('gh7421_1', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create([{}], {validateBeforeSave: false}, function(createError, docs) {
         assert.equal(createError, null);
@@ -2463,7 +2485,7 @@ describe('document', function() {
     it('filters out validation on unmodified paths when validateModifiedOnly set (gh-7421)', function(done) {
       const testSchema = new Schema({ title: { type: String, required: true }, other: String });
 
-      const Test = db.model('gh7421_2', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create([{}], {validateBeforeSave: false}, function(createError, docs) {
         assert.equal(createError, null);
@@ -2480,7 +2502,7 @@ describe('document', function() {
     it('does not filter validation on modified paths when validateModifiedOnly set (gh-7421)', function(done) {
       const testSchema = new Schema({ title: { type: String, required: true }, other: String });
 
-      const Test = db.model('gh7421_3', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create([{title: 'title'}], {validateBeforeSave: false}, function(createError, docs) {
         assert.equal(createError, null);
@@ -2500,7 +2522,7 @@ describe('document', function() {
         coverId: Number
       }, { validateModifiedOnly: true });
 
-      const Model = db.model('gh8091', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.collection.insertOne({ title: 'foo', coverId: parseFloat('not a number') });
@@ -2525,7 +2547,7 @@ describe('document', function() {
         next(new Error('Catch all #2'));
       });
 
-      const Model = db.model('gh2284_1', schema);
+      const Model = db.model('Test', schema);
 
       Model.create({ name: 'test' }, function(error) {
         assert.ifError(error);
@@ -2548,12 +2570,12 @@ describe('document', function() {
     it('single embedded schemas with populate (gh-3501)', function(done) {
       const PopulateMeSchema = new Schema({});
 
-      const Child = db.model('gh3501', PopulateMeSchema);
+      const Child = db.model('Child', PopulateMeSchema);
 
       const SingleNestedSchema = new Schema({
         populateMeArray: [{
           type: Schema.Types.ObjectId,
-          ref: 'gh3501'
+          ref: 'Child'
         }]
       });
 
@@ -2561,7 +2583,7 @@ describe('document', function() {
         singleNested: SingleNestedSchema
       });
 
-      const P = db.model('gh3501_1', parentSchema);
+      const P = db.model('Parent', parentSchema);
 
       Child.create([{}, {}], function(error, docs) {
         assert.ifError(error);

From b3d5faa157c87469db59dc546d16c4d7633b888a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 16:42:43 -0500
Subject: [PATCH 0359/2348] Actually fix #8479

---
 lib/schema/documentarray.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 286c6247915..06c6a0b5e74 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -20,6 +20,7 @@ const getConstructor = require('../helpers/discriminator/getConstructor');
 
 const arrayParentSymbol = require('../helpers/symbols').arrayParentSymbol;
 const arrayPathSymbol = require('../helpers/symbols').arrayPathSymbol;
+const documentArrayParent = require('../helpers/symbols').documentArrayParent;
 
 let MongooseDocumentArray;
 let Subdocument;
@@ -393,7 +394,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
 
     // Check if the document has a different schema (re gh-3701)
     if ((value[i].$__) &&
-        !(value[i] instanceof Constructor)) {
+        (!(value[i] instanceof Constructor) || value[i][documentArrayParent] !== doc)) {
       value[i] = value[i].toObject({
         transform: false,
         // Special case: if different model, but same schema, apply virtuals

From 2a18b0f9f3f5d7c9e6a4ad16263110e50ad865f4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 16:48:13 -0500
Subject: [PATCH 0360/2348] test: fix tests re: #8481

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 2589bdb86e2..e9c0fcf38e7 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2071,7 +2071,7 @@ describe('document', function() {
   describe('bug fixes', function() {
     it('applies toJSON transform correctly for populated docs (gh-2910) (gh-2990)', function(done) {
       const parentSchema = mongoose.Schema({
-        c: {type: mongoose.Schema.Types.ObjectId, ref: 'gh-2910-1'}
+        c: {type: mongoose.Schema.Types.ObjectId, ref: 'Child'}
       });
 
       let called = [];

From c866866964a591fea3653d8c4241316448458253 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 16:57:34 -0500
Subject: [PATCH 0361/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 60767b50353..051eefd4fca 100644
--- a/index.pug
+++ b/index.pug
@@ -274,6 +274,9 @@ html(lang='en')
               <a href="https://www.minitool.com/">
                 <img class="sponsor" src="https://images.opencollective.com/minitool-solution-ltd/1519aa6/logo.png" style="height: 100px">
               </a>
+              <a href="https://synapsesearch.nz/">
+                <img class="sponsor" src="https://images.opencollective.com/synapsesearch/9f0bc41/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From a4d623ede734befc84fcf1b21f82cf21af6022c9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jan 2020 17:06:48 -0500
Subject: [PATCH 0362/2348] chore: release 5.8.7

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index d3e680a635e..bcb71cbf548 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.8.7 / 2020-01-10
+==================
+ * fix(documentarray): modify ownerDocument when setting doc array to a doc array thats part of another document #8479
+ * fix(document): ensure that you can call `splice()` after `slice()` on an array #8482
+ * docs(populate): improve cross-db populate docs to include model refs #8497
+
 5.8.6 / 2020-01-07
 ====================
  * chore: merge changes from 4.13.20 and override mistaken publish to latest tag
diff --git a/package.json b/package.json
index 438c2fb8c95..8ea1be895fc 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.7-pre",
+  "version": "5.8.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From c4e80019fbfdedba3809db5627e1c951da1d505f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Jan 2020 04:48:44 -0800
Subject: [PATCH 0363/2348] fixes #8500

---
 lib/validoptions.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/validoptions.js b/lib/validoptions.js
index 7ae1a8bb874..9464e4d8611 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -23,7 +23,8 @@ const VALID_OPTIONS = Object.freeze([
   'useFindAndModify',
   'useNewUrlParser',
   'usePushEach',
-  'useUnifiedTopology'
+  'useUnifiedTopology',
+  'typePojoToMixed'
 ]);
 
-module.exports = VALID_OPTIONS;
\ No newline at end of file
+module.exports = VALID_OPTIONS;

From a8c588a8cc3d380fd76e6f901bb257f04f9d669c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Jan 2020 12:39:55 -0500
Subject: [PATCH 0364/2348] docs(populate+schematypes): make note of `_id`
 getter for ObjectIds in populate docs

Fix #8483
---
 docs/populate.pug    | 29 +++++++++++++++++++++++++++++
 docs/schematypes.pug | 26 +++++++++++++++++++++-----
 2 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 9681271c9cb..c3e551b322b 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -56,6 +56,7 @@ block content
     <ul class="toc">
       <li><a href="#saving-refs">Saving Refs</a></li>
       <li><a href="#population">Population</a></li>
+      <li><a href="#checking-populated">Checking Whether a Field is Populated</a></li>
       <li><a href="#setting-populated-fields">Setting Populated Fields</a></li>
       <li><a href="#doc-not-found">What If There's No Foreign Document?</a></li>
       <li><a href="#field-selection">Field Selection</a></li>
@@ -139,6 +140,34 @@ block content
     });
     ```
 
+    <h3 id="checking-populated"><a href="#checking-populated">Checking Whether a Field is Populated</a></h3>
+
+    You can call the `populated()` function to check whether a field is populated.
+    If `populated()` returns a [truthy value](https://masteringjs.io/tutorials/fundamentals/truthy),
+    you can assume the field is populated.
+
+    ```javascript
+    story.populated('author'); // truthy
+
+    story.depopulate('author'); // Make `author` not populated anymore
+    story.populated('author'); // falsy
+    ```
+
+    A common reason for checking whether a path is populated is getting the `author`
+    id. However, for your convenience, Mongoose adds a [`_id` getter to ObjectId instances](/docs/api/mongoose.html#mongoose_Mongoose-set)
+    so you can use `story.author._id` regardless of whether `author` is populated.
+
+    ```javascript
+    story.populated('author'); // truthy
+    story.author._id; // ObjectId
+
+    story.depopulate('author'); // Make `author` not populated anymore
+    story.populated('author'); // falsy
+
+    story.author instanceof ObjectId; // true
+    story.author._id; // ObjectId, because Mongoose adds a special getter
+    ```
+
     <h3 id="doc-not-found"><a href="#doc-not-found">What If There's No Foreign Document?</a></h3>
 
     Mongoose populate doesn't behave like conventional
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index b79b157415b..2d086b9663b 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -427,13 +427,29 @@ block content
 
     <h4 id="objectids">ObjectIds</h4>
 
-    To specify a type of ObjectId, use `Schema.Types.ObjectId` in your declaration.
+    An [ObjectId](https://docs.mongodb.com/manual/reference/method/ObjectId/)
+    is a special type typically used for unique identifiers. Here's how
+    you declare a schema with a path `driver` that is an ObjectId:
 
     ```javascript
-    var mongoose = require('mongoose');
-    var ObjectId = mongoose.Schema.Types.ObjectId;
-    var Car = new Schema({ driver: ObjectId });
-    // or just Schema.ObjectId for backwards compatibility with v2
+    const mongoose = require('mongoose');
+    const carSchema = new mongoose.Schema({ driver: mongoose.ObjectId });
+    ```
+
+    `ObjectId` is a class, and ObjectIds are objects. However, they are
+    often represented as strings. When you convert an ObjectId to a string
+    using `toString()`, you get a 24-character hexadecimal string:
+
+    ```javascript
+    const Car = mongoose.model('Car', carSchema);
+
+    const car = new Car();
+    car.driver = new mongoose.Types.ObjectId();
+
+    typeof car.driver; // 'object'
+    car.driver instanceof mongoose.Types.ObjectId; // true
+
+    car.driver.toString(); // Something like "5e1a0651741b255ddda996c4"
     ```
 
     <h4 id="booleans">Boolean</h4>

From 9acda51b24dcf3dd8ae21c287108e2e3f62fb774 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 12 Jan 2020 12:51:04 -0500
Subject: [PATCH 0365/2348] chore: now working on 5.8.8

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 8ea1be895fc..a1b9b220569 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.7",
+  "version": "5.8.8-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 87d4d8e8bb976f9ed177dbf41ed754fb1cd8c654 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 13:52:16 -0500
Subject: [PATCH 0366/2348] test(document): repro #8486

---
 test/document.test.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index e9c0fcf38e7..502863ecbbb 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8474,4 +8474,33 @@ describe('document', function() {
       assert.equal(err.name, 'ParallelValidateError');
     });
   });
+
+  it('avoids parallel validate error when validating nested path with double nested subdocs (gh-8486)', function() {
+    const testSchema = new Schema({
+      foo: {
+        bar: Schema({
+          baz: Schema({
+            num: Number
+          })
+        })
+      }
+    });
+    const Test = db.model('gh8486', testSchema);
+    
+    return co(function*() {
+      const doc = yield Test.create({});
+
+      doc.foo = {
+        bar: {
+          baz: {
+            num: 1
+          }
+        }
+      };
+      yield doc.save();
+
+      const raw = yield Test.collection.findOne();
+      assert.equal(raw.foo.bar.baz.num, 1);
+    });
+  });
 });

From beb789fa68de61de78c274ad6bb2ea71ed3bf144 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 13:52:32 -0500
Subject: [PATCH 0367/2348] fix(document): don't throw parallel validate error
 when validating subdoc underneath modified nested path

Fix #8486
---
 lib/document.js       | 10 +++++-----
 test/document.test.js |  4 +++-
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0e7d033e46b..0444fd3b18c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2097,11 +2097,6 @@ function _getPathsToValidate(doc) {
   paths = paths.concat(Object.keys(doc.$__.activePaths.states.modify));
   paths = paths.concat(Object.keys(doc.$__.activePaths.states.default));
 
-  // Single nested paths (paths embedded under single nested subdocs) will
-  // be validated on their own when we call `validate()` on the subdoc itself.
-  // Re: gh-8468
-  paths = paths.filter(p => !doc.schema.singleNestedPaths.hasOwnProperty(p));
-
   if (!doc.ownerDocument) {
     const subdocs = doc.$__getAllSubdocs();
     let subdoc;
@@ -2170,6 +2165,11 @@ function _getPathsToValidate(doc) {
     }
   }
 
+  // Single nested paths (paths embedded under single nested subdocs) will
+  // be validated on their own when we call `validate()` on the subdoc itself.
+  // Re: gh-8468
+  paths = paths.filter(p => !doc.schema.singleNestedPaths.hasOwnProperty(p));
+
   len = paths.length;
   for (i = 0; i < len; ++i) {
     const path = paths[i];
diff --git a/test/document.test.js b/test/document.test.js
index 502863ecbbb..5b551df290e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8486,7 +8486,7 @@ describe('document', function() {
       }
     });
     const Test = db.model('gh8486', testSchema);
-    
+
     return co(function*() {
       const doc = yield Test.create({});
 
@@ -8497,6 +8497,8 @@ describe('document', function() {
           }
         }
       };
+
+      // Should not throw
       yield doc.save();
 
       const raw = yield Test.collection.findOne();

From 91bab9f6e9e4e0ef7335d136865b847a5679f69b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 14:34:33 -0500
Subject: [PATCH 0368/2348] test(query): reuse collections where possible in
 query tests, reduce runtime from 40s to 15s on my linux laptop

Re: #8481
---
 test/query.test.js | 522 +++++++++++++++++++++++----------------------
 1 file changed, 267 insertions(+), 255 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index e1533df1a51..f688b431d23 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -9,7 +9,6 @@ const start = require('./common');
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -20,32 +19,23 @@ const DocumentObjectId = mongoose.Types.ObjectId;
  */
 
 describe('Query', function() {
-  let Comment;
-  let Product;
-  let p1;
+  let commentSchema;
+  let productSchema;
   let db;
 
   before(function() {
-    Comment = new Schema({
+    commentSchema = new Schema({
       text: String
     });
 
-    Product = new Schema({
+    productSchema = new Schema({
       tags: {}, // mixed
       array: Array,
       ids: [Schema.ObjectId],
       strings: [String],
       numbers: [Number],
-      comments: [Comment]
+      comments: [commentSchema]
     });
-
-    mongoose.model('Product', Product);
-    mongoose.model('Comment', Comment);
-  });
-
-  before(function() {
-    const Prod = mongoose.model('Product');
-    p1 = new Prod();
   });
 
   before(function() {
@@ -56,10 +46,25 @@ describe('Query', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => {
+    const arr = [];
+
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
   describe('constructor', function() {
     it('should not corrupt options', function(done) {
       const opts = {};
-      const query = new Query({}, opts, null, p1.collection);
+      const query = new Query({}, opts, null);
       assert.notEqual(opts, query._mongooseOptions);
       done();
     });
@@ -67,14 +72,14 @@ describe('Query', function() {
 
   describe('select', function() {
     it('(object)', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.select({a: 1, b: 1, c: 0});
       assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
       done();
     });
 
     it('(string)', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.select(' a  b -c ');
       assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
       done();
@@ -82,14 +87,14 @@ describe('Query', function() {
 
     it('("a","b","c")', function(done) {
       assert.throws(function() {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.select('a', 'b', 'c');
       }, /Invalid select/);
       done();
     });
 
     it('should not overwrite fields set in prior calls', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.select('a');
       assert.deepEqual(query._fields, {a: 1});
       query.select('b');
@@ -104,13 +109,13 @@ describe('Query', function() {
 
   describe('projection() (gh-7384)', function() {
     it('gets current projection', function() {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.select('a');
       assert.deepEqual(query.projection(), { a: 1 });
     });
 
     it('overwrites current projection', function() {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.select('a');
       assert.deepEqual(query.projection({ b: 1 }), { b: 1 });
       assert.deepEqual(query.projection(), { b: 1 });
@@ -119,7 +124,7 @@ describe('Query', function() {
 
   describe('where', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('name', 'guillermo');
       assert.deepEqual(query._conditions, {name: 'guillermo'});
       query.where('a');
@@ -128,7 +133,7 @@ describe('Query', function() {
       done();
     });
     it('throws if non-string or non-object path is passed', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       assert.throws(function() {
         query.where(50);
       });
@@ -138,7 +143,7 @@ describe('Query', function() {
       done();
     });
     it('does not throw when 0 args passed', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       assert.doesNotThrow(function() {
         query.where();
       });
@@ -148,7 +153,7 @@ describe('Query', function() {
 
   describe('equals', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('name').equals('guillermo');
       assert.deepEqual(query._conditions, {name: 'guillermo'});
       done();
@@ -157,13 +162,13 @@ describe('Query', function() {
 
   describe('gte', function() {
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.gte('age', 18);
       assert.deepEqual(query._conditions, {age: {$gte: 18}});
       done();
     });
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').gte(18);
       assert.deepEqual(query._conditions, {age: {$gte: 18}});
       done();
@@ -172,13 +177,13 @@ describe('Query', function() {
 
   describe('gt', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').gt(17);
       assert.deepEqual(query._conditions, {age: {$gt: 17}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.gt('age', 17);
       assert.deepEqual(query._conditions, {age: {$gt: 17}});
       done();
@@ -187,13 +192,13 @@ describe('Query', function() {
 
   describe('lte', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').lte(65);
       assert.deepEqual(query._conditions, {age: {$lte: 65}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.lte('age', 65);
       assert.deepEqual(query._conditions, {age: {$lte: 65}});
       done();
@@ -202,13 +207,13 @@ describe('Query', function() {
 
   describe('lt', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').lt(66);
       assert.deepEqual(query._conditions, {age: {$lt: 66}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.lt('age', 66);
       assert.deepEqual(query._conditions, {age: {$lt: 66}});
       done();
@@ -218,7 +223,7 @@ describe('Query', function() {
   describe('combined', function() {
     describe('lt and gt', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('age').lt(66).gt(17);
         assert.deepEqual(query._conditions, {age: {$lt: 66, $gt: 17}});
         done();
@@ -228,7 +233,7 @@ describe('Query', function() {
 
   describe('tl on one path and gt on another', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query
         .where('age').lt(66)
         .where('height').gt(5);
@@ -239,13 +244,13 @@ describe('Query', function() {
 
   describe('ne', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').ne(21);
       assert.deepEqual(query._conditions, {age: {$ne: 21}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.ne('age', 21);
       assert.deepEqual(query._conditions, {age: {$ne: 21}});
       done();
@@ -254,25 +259,25 @@ describe('Query', function() {
 
   describe('in', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').in([21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$in: [21, 25, 30]}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.in('age', [21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$in: [21, 25, 30]}});
       done();
     });
     it('where a non-array value no via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.in('age', 21);
       assert.deepEqual(query._conditions, {age: {$in: 21}});
       done();
     });
     it('where a non-array value via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').in(21);
       assert.deepEqual(query._conditions, {age: {$in: 21}});
       done();
@@ -281,25 +286,25 @@ describe('Query', function() {
 
   describe('nin', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').nin([21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$nin: [21, 25, 30]}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.nin('age', [21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$nin: [21, 25, 30]}});
       done();
     });
     it('with a non-array value not via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.nin('age', 21);
       assert.deepEqual(query._conditions, {age: {$nin: 21}});
       done();
     });
     it('with a non-array value via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').nin(21);
       assert.deepEqual(query._conditions, {age: {$nin: 21}});
       done();
@@ -308,25 +313,25 @@ describe('Query', function() {
 
   describe('mod', function() {
     it('not via where, where [a, b] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.mod('age', [5, 2]);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
     });
     it('not via where, where a and b params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.mod('age', 5, 2);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
     });
     it('via where, where [a, b] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').mod([5, 2]);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
     });
     it('via where, where a and b params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('age').mod(5, 2);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
@@ -335,46 +340,46 @@ describe('Query', function() {
 
   describe('near', function() {
     it('via where, where { center :[lat, long]} param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').near({center: [40, -72]});
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').near([40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').near(40, -72);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('not via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.near('checkin', [40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('not via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.near('checkin', 40, -72);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('via where, where GeoJSON param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('numbers').near({center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {numbers: {$near: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       assert.doesNotThrow(function() {
-        query.cast(p1.constructor);
+        query.cast(db.model('Product', productSchema));
       });
       done();
     });
     it('with path, where GeoJSON param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.near('loc', {center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {loc: {$near: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       done();
@@ -383,53 +388,53 @@ describe('Query', function() {
 
   describe('nearSphere', function() {
     it('via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').nearSphere([40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
     it('via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').nearSphere(40, -72);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
     it('not via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.nearSphere('checkin', [40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
     it('not via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.nearSphere('checkin', 40, -72);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
 
     it('via where, with object', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').nearSphere({center: [20, 23], maxDistance: 2});
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [20, 23], $maxDistance: 2}});
       done();
     });
 
     it('via where, where GeoJSON param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('numbers').nearSphere({center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {numbers: {$nearSphere: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       assert.doesNotThrow(function() {
-        query.cast(p1.constructor);
+        query.cast(db.model('Product', productSchema));
       });
       done();
     });
 
     it('with path, with GeoJSON', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.nearSphere('numbers', {center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {numbers: {$nearSphere: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       assert.doesNotThrow(function() {
-        query.cast(p1.constructor);
+        query.cast(db.model('Product', productSchema));
       });
       done();
     });
@@ -437,7 +442,7 @@ describe('Query', function() {
 
   describe('maxDistance', function() {
     it('via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('checkin').near([40, -72]).maxDistance(1);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72], $maxDistance: 1}});
       done();
@@ -447,7 +452,7 @@ describe('Query', function() {
   describe('within', function() {
     describe('box', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('gps').within().box({ll: [5, 25], ur: [10, 30]});
         const match = {gps: {$within: {$box: [[5, 25], [10, 30]]}}};
         if (Query.use$geoWithin) {
@@ -458,7 +463,7 @@ describe('Query', function() {
         done();
       });
       it('via where, no object', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('gps').within().box([5, 25], [10, 30]);
         const match = {gps: {$within: {$box: [[5, 25], [10, 30]]}}};
         if (Query.use$geoWithin) {
@@ -472,7 +477,7 @@ describe('Query', function() {
 
     describe('center', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('gps').within().center({center: [5, 25], radius: 5});
         const match = {gps: {$within: {$center: [[5, 25], 5]}}};
         if (Query.use$geoWithin) {
@@ -486,7 +491,7 @@ describe('Query', function() {
 
     describe('centerSphere', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('gps').within().centerSphere({center: [5, 25], radius: 5});
         const match = {gps: {$within: {$centerSphere: [[5, 25], 5]}}};
         if (Query.use$geoWithin) {
@@ -500,7 +505,7 @@ describe('Query', function() {
 
     describe('polygon', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('gps').within().polygon({a: {x: 10, y: 20}, b: {x: 15, y: 25}, c: {x: 20, y: 20}});
         const match = {gps: {$within: {$polygon: [{a: {x: 10, y: 20}, b: {x: 15, y: 25}, c: {x: 20, y: 20}}]}}};
         if (Query.use$geoWithin) {
@@ -515,26 +520,26 @@ describe('Query', function() {
 
   describe('exists', function() {
     it('0 args via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('username').exists();
       assert.deepEqual(query._conditions, {username: {$exists: true}});
       done();
     });
     it('1 arg via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('username').exists(false);
       assert.deepEqual(query._conditions, {username: {$exists: false}});
       done();
     });
     it('where 1 argument not via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.exists('username');
       assert.deepEqual(query._conditions, {username: {$exists: true}});
       done();
     });
 
     it('where 2 args not via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.exists('username', false);
       assert.deepEqual(query._conditions, {username: {$exists: false}});
       done();
@@ -543,13 +548,13 @@ describe('Query', function() {
 
   describe('all', function() {
     it('via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('pets').all(['dog', 'cat', 'ferret']);
       assert.deepEqual(query._conditions, {pets: {$all: ['dog', 'cat', 'ferret']}});
       done();
     });
     it('not via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.all('pets', ['dog', 'cat', 'ferret']);
       assert.deepEqual(query._conditions, {pets: {$all: ['dog', 'cat', 'ferret']}});
       done();
@@ -558,14 +563,14 @@ describe('Query', function() {
 
   describe('find', function() {
     it('strict array equivalence condition v', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.find({pets: ['dog', 'cat', 'ferret']});
       assert.deepEqual(query._conditions, {pets: ['dog', 'cat', 'ferret']});
       done();
     });
     it('with no args', function(done) {
       let threw = false;
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
 
       try {
         q.find();
@@ -578,7 +583,7 @@ describe('Query', function() {
     });
 
     it('works with overwriting previous object args (1176)', function(done) {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       assert.doesNotThrow(function() {
         q.find({age: {$lt: 30}});
         q.find({age: 20}); // overwrite
@@ -590,13 +595,13 @@ describe('Query', function() {
 
   describe('size', function() {
     it('via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').size(5);
       assert.deepEqual(query._conditions, {collection: {$size: 5}});
       done();
     });
     it('not via where', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.size('collection', 5);
       assert.deepEqual(query._conditions, {collection: {$size: 5}});
       done();
@@ -605,73 +610,73 @@ describe('Query', function() {
 
   describe('slice', function() {
     it('where and positive limit param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice(5);
       assert.deepEqual(query._fields, {collection: {$slice: 5}});
       done();
     });
     it('where just negative limit param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice(-5);
       assert.deepEqual(query._fields, {collection: {$slice: -5}});
       done();
     });
     it('where [skip, limit] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice([14, 10]); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('where skip and limit params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice(14, 10); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('where just positive limit param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice(5);
       assert.deepEqual(query._fields, {collection: {$slice: 5}});
       done();
     });
     it('where just negative limit param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice(-5);
       assert.deepEqual(query._fields, {collection: {$slice: -5}});
       done();
     });
     it('where the [skip, limit] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice([14, 10]); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('where the skip and limit params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.where('collection').slice(14, 10); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('not via where, with just positive limit param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.slice('collection', 5);
       assert.deepEqual(query._fields, {collection: {$slice: 5}});
       done();
     });
     it('not via where, where just negative limit param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.slice('collection', -5);
       assert.deepEqual(query._fields, {collection: {$slice: -5}});
       done();
     });
     it('not via where, where [skip, limit] param', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.slice('collection', [14, 10]); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('not via where, where skip and limit params', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.slice('collection', 14, 10); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
@@ -681,13 +686,13 @@ describe('Query', function() {
   describe('elemMatch', function() {
     describe('not via where', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.elemMatch('comments', {author: 'bnoguchi', votes: {$gte: 5}});
         assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
         done();
       });
       it('where block notation', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.elemMatch('comments', function(elem) {
           elem.where('author', 'bnoguchi');
           elem.where('votes').gte(5);
@@ -698,13 +703,13 @@ describe('Query', function() {
     });
     describe('via where', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('comments').elemMatch({author: 'bnoguchi', votes: {$gte: 5}});
         assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
         done();
       });
       it('where block notation', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.where('comments').elemMatch(function(elem) {
           elem.where('author', 'bnoguchi');
           elem.where('votes').gte(5);
@@ -717,7 +722,7 @@ describe('Query', function() {
 
   describe('$where', function() {
     it('function arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
 
       function filter() {
         return this.lastName === this.firstName;
@@ -728,7 +733,7 @@ describe('Query', function() {
       done();
     });
     it('string arg', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.$where('this.lastName === this.firstName');
       assert.deepEqual(query._conditions, {$where: 'this.lastName === this.firstName'});
       done();
@@ -737,7 +742,7 @@ describe('Query', function() {
 
   describe('limit', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.limit(5);
       assert.equal(query.options.limit, 5);
       done();
@@ -746,7 +751,7 @@ describe('Query', function() {
 
   describe('skip', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
+      const query = new Query({}, {}, null);
       query.skip(9);
       assert.equal(query.options.skip, 9);
       done();
@@ -755,21 +760,21 @@ describe('Query', function() {
 
   describe('sort', function() {
     it('works', function(done) {
-      let query = new Query({}, {}, null, p1.collection);
+      let query = new Query({}, {}, null);
       query.sort('a -c b');
       assert.deepEqual(query.options.sort, {a: 1, c: -1, b: 1});
-      query = new Query({}, {}, null, p1.collection);
+      query = new Query({}, {}, null);
       query.sort({a: 1, c: -1, b: 'asc', e: 'descending', f: 'ascending'});
       assert.deepEqual(query.options.sort, {a: 1, c: -1, b: 1, e: -1, f: 1});
 
       if (typeof global.Map !== 'undefined') {
-        query = new Query({}, {}, null, p1.collection);
+        query = new Query({}, {}, null);
         query.sort(new global.Map().set('a', 1).set('b', 1));
         assert.equal(query.options.sort.get('a'), 1);
         assert.equal(query.options.sort.get('b'), 1);
       }
 
-      query = new Query({}, {}, null, p1.collection);
+      query = new Query({}, {}, null);
       let e;
 
       try {
@@ -830,7 +835,7 @@ describe('Query', function() {
 
   describe('populate', function() {
     it('converts to PopulateOptions objects', function(done) {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       const o = {
         path: 'yellow.brick',
         match: {bricks: {$lt: 1000}},
@@ -845,7 +850,7 @@ describe('Query', function() {
     });
 
     it('overwrites duplicate paths', function(done) {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       let o = {
         path: 'yellow.brick',
         match: {bricks: {$lt: 1000}},
@@ -866,7 +871,7 @@ describe('Query', function() {
     });
 
     it('accepts space delimited strings', function(done) {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       q.populate('yellow.brick dirt');
       assert.equal(Object.keys(q._mongooseOptions.populate).length, 2);
       assert.deepEqual(q._mongooseOptions.populate['yellow.brick'], {
@@ -883,8 +888,8 @@ describe('Query', function() {
 
   describe('casting', function() {
     it('to an array of mixed', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
-      const Product = db.model('Product');
+      const query = new Query({}, {}, null);
+      const Product = db.model('Product', productSchema);
       const params = {_id: new DocumentObjectId, tags: {$in: [4, 8, 15, 16]}};
       query.cast(Product, params);
       assert.deepEqual(params.tags.$in, [4, 8, 15, 16]);
@@ -901,7 +906,7 @@ describe('Query', function() {
         props: [embeddedSchema]
       });
 
-      const Cat = db.model('gh6439', catSchema);
+      const Cat = db.model('Cat', catSchema);
       const kitty = new Cat({
         name: 'Zildjian',
         props: [
@@ -931,9 +936,9 @@ describe('Query', function() {
     });
 
     it('find $ne should not cast single value to array for schematype of Array', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
-      const Product = db.model('Product');
-      const Comment = db.model('Comment');
+      const query = new Query({}, {}, null);
+      const Product = db.model('Product', productSchema);
+      const Comment = db.model('Comment', commentSchema);
 
       const id = new DocumentObjectId;
       const castedComment = {_id: id, text: 'hello there'};
@@ -975,8 +980,8 @@ describe('Query', function() {
     });
 
     it('subdocument array with $ne: null should not throw', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
-      const Product = db.model('Product');
+      const query = new Query({}, {}, null);
+      const Product = db.model('Product', productSchema);
 
       const params = {
         comments: {$ne: null}
@@ -988,9 +993,9 @@ describe('Query', function() {
     });
 
     it('find should not cast single value to array for schematype of Array', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
-      const Product = db.model('Product');
-      const Comment = db.model('Comment');
+      const query = new Query({}, {}, null);
+      const Product = db.model('Product', productSchema);
+      const Comment = db.model('Comment', commentSchema);
 
       const id = new DocumentObjectId;
       const castedComment = {_id: id, text: 'hello there'};
@@ -1032,8 +1037,8 @@ describe('Query', function() {
     });
 
     it('an $elemMatch with $in works (gh-1100)', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
-      const Product = db.model('Product');
+      const query = new Query({}, {}, null);
+      const Product = db.model('Product', productSchema);
       const ids = [String(new DocumentObjectId), String(new DocumentObjectId)];
       const params = {ids: {$elemMatch: {$in: ids}}};
       query.cast(Product, params);
@@ -1045,9 +1050,9 @@ describe('Query', function() {
     });
 
     it('inequality operators for an array', function(done) {
-      const query = new Query({}, {}, null, p1.collection);
-      const Product = db.model('Product');
-      const Comment = db.model('Comment');
+      const query = new Query({}, {}, null);
+      const Product = db.model('Product', productSchema);
+      const Comment = db.model('Comment', commentSchema);
 
       const id = new DocumentObjectId;
       const castedComment = {_id: id, text: 'hello there'};
@@ -1071,7 +1076,7 @@ describe('Query', function() {
 
   describe('distinct', function() {
     it('op', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
       const prod = new Product({});
       const q = new Query({}, {}, Product, prod.collection).distinct('blah', function() {
         assert.equal(q.op, 'distinct');
@@ -1082,7 +1087,7 @@ describe('Query', function() {
 
   describe('findOne', function() {
     it('sets the op', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
       const prod = new Product({});
       const q = new Query(prod.collection, {}, Product).distinct();
       // use a timeout here because we have to wait for the connection to start
@@ -1096,7 +1101,7 @@ describe('Query', function() {
     });
 
     it('works as a promise', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
       const promise = Product.findOne();
 
       promise.then(function() {
@@ -1109,7 +1114,7 @@ describe('Query', function() {
 
   describe('deleteOne/deleteMany', function() {
     it('handles deleteOne', function(done) {
-      const M = db.model('deleteOne', new Schema({ name: 'String' }));
+      const M = db.model('Person', new Schema({ name: 'String' }));
       M.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
         assert.ifError(error);
         M.deleteOne({ name: /Stark/ }, function(error) {
@@ -1124,7 +1129,7 @@ describe('Query', function() {
     });
 
     it('handles deleteMany', function(done) {
-      const M = db.model('deleteMany', new Schema({ name: 'String' }));
+      const M = db.model('Person', new Schema({ name: 'String' }));
       M.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
         assert.ifError(error);
         M.deleteMany({ name: /Stark/ }, function(error) {
@@ -1141,7 +1146,7 @@ describe('Query', function() {
 
   describe('remove', function() {
     it('handles cast errors async', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
 
       assert.doesNotThrow(function() {
         Product.where({numbers: [[[]]]}).deleteMany(function(err) {
@@ -1152,7 +1157,7 @@ describe('Query', function() {
     });
 
     it('supports a single conditions arg', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
 
       Product.create({strings: ['remove-single-condition']}).then(function() {
         const q = Product.where().deleteMany({strings: 'remove-single-condition'});
@@ -1162,7 +1167,7 @@ describe('Query', function() {
     });
 
     it('supports a single callback arg', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
       const val = 'remove-single-callback';
 
       Product.create({strings: [val]}).then(function() {
@@ -1178,7 +1183,7 @@ describe('Query', function() {
     });
 
     it('supports conditions and callback args', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
       const val = 'remove-cond-and-callback';
 
       Product.create({strings: [val]}).then(function() {
@@ -1194,7 +1199,7 @@ describe('Query', function() {
     });
 
     it('single option, default', function(done) {
-      const Test = db.model('Test_single', new Schema({ name: String }));
+      const Test = db.model('Person', new Schema({ name: String }));
 
       Test.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
         assert.ifError(error);
@@ -1211,7 +1216,7 @@ describe('Query', function() {
     });
 
     it.skip('single option, false', function(done) {
-      const Test = db.model('Test_single_false', new Schema({ name: String }));
+      const Test = db.model('Person', new Schema({ name: String }));
 
       Test.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
         assert.ifError(error);
@@ -1228,7 +1233,7 @@ describe('Query', function() {
     });
 
     it.skip('single option, true', function(done) {
-      const Test = db.model('Test_single_true', new Schema({ name: String }));
+      const Test = db.model('Person', new Schema({ name: String }));
 
       Test.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
         assert.ifError(error);
@@ -1247,7 +1252,7 @@ describe('Query', function() {
 
   describe('querying/updating with model instance containing embedded docs should work (#454)', function() {
     it('works', function(done) {
-      const Product = db.model('Product');
+      const Product = db.model('Product', productSchema);
 
       const proddoc = {comments: [{text: 'hello'}]};
       const prod2doc = {comments: [{text: 'goodbye'}]};
@@ -1330,7 +1335,7 @@ describe('Query', function() {
   describe('options', function() {
     describe('maxscan', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.maxscan(100);
         assert.equal(query.options.maxScan, 100);
         done();
@@ -1339,15 +1344,15 @@ describe('Query', function() {
 
     describe('slaveOk', function() {
       it('works', function(done) {
-        let query = new Query({}, {}, null, p1.collection);
+        let query = new Query({}, {}, null);
         query.slaveOk();
         assert.equal(query.options.slaveOk, true);
 
-        query = new Query({}, {}, null, p1.collection);
+        query = new Query({}, {}, null);
         query.slaveOk(true);
         assert.equal(query.options.slaveOk, true);
 
-        query = new Query({}, {}, null, p1.collection);
+        query = new Query({}, {}, null);
         query.slaveOk(false);
         assert.equal(query.options.slaveOk, false);
         done();
@@ -1356,21 +1361,21 @@ describe('Query', function() {
 
     describe('tailable', function() {
       it('works', function(done) {
-        let query = new Query({}, {}, null, p1.collection);
+        let query = new Query({}, {}, null);
         query.tailable();
         assert.equal(query.options.tailable, true);
 
-        query = new Query({}, {}, null, p1.collection);
+        query = new Query({}, {}, null);
         query.tailable(true);
         assert.equal(query.options.tailable, true);
 
-        query = new Query({}, {}, null, p1.collection);
+        query = new Query({}, {}, null);
         query.tailable(false);
         assert.equal(query.options.tailable, false);
         done();
       });
       it('supports passing the `await` option', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.tailable({awaitdata: true});
         assert.equal(query.options.tailable, true);
         assert.equal(query.options.awaitdata, true);
@@ -1390,11 +1395,11 @@ describe('Query', function() {
 
     describe('hint', function() {
       it('works', function(done) {
-        const query2 = new Query({}, {}, null, p1.collection);
+        const query2 = new Query({}, {}, null);
         query2.hint({indexAttributeA: 1, indexAttributeB: -1});
         assert.deepEqual(query2.options.hint, {indexAttributeA: 1, indexAttributeB: -1});
 
-        const query3 = new Query({}, {}, null, p1.collection);
+        const query3 = new Query({}, {}, null);
         query3.hint('indexAttributeA_1');
         assert.deepEqual(query3.options.hint, 'indexAttributeA_1');
 
@@ -1404,7 +1409,7 @@ describe('Query', function() {
 
     describe('snapshot', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.snapshot(true);
         assert.equal(query.options.snapshot, true);
         done();
@@ -1413,7 +1418,7 @@ describe('Query', function() {
 
     describe('batchSize', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null, p1.collection);
+        const query = new Query({}, {}, null);
         query.batchSize(10);
         assert.equal(query.options.batchSize, 10);
         done();
@@ -1425,7 +1430,7 @@ describe('Query', function() {
 
       describe('without tags', function() {
         it('works', function(done) {
-          const query = new Query({}, {}, null, p1.collection);
+          const query = new Query({}, {}, null);
           query.read('primary');
           assert.ok(query.options.readPreference instanceof P);
           assert.ok(query.options.readPreference.isValid());
@@ -1482,7 +1487,7 @@ describe('Query', function() {
 
       describe('with tags', function() {
         it('works', function(done) {
-          const query = new Query({}, {}, null, p1.collection);
+          const query = new Query({}, {}, null);
           const tags = [{dc: 'sf', s: 1}, {dc: 'jp', s: 2}];
 
           query.read('pp', tags);
@@ -1522,7 +1527,7 @@ describe('Query', function() {
         it('and sends it though the driver', function(done) {
           const options = {read: 'secondary', safe: {w: 'majority'}};
           const schema = new Schema({name: String}, options);
-          const M = db.model(random(), schema);
+          const M = db.model('Test', schema);
           const q = M.find();
 
           // stub the internal query options call
@@ -1558,7 +1563,7 @@ describe('Query', function() {
             nested: subSchema
           }, { strict: 'throw' });
 
-          const Test = db.model('gh5144', schema);
+          const Test = db.model('Test', schema);
           const test = new Test({ name: 'Test1' });
           return co(function*() {
             yield test.save();
@@ -1577,7 +1582,7 @@ describe('Query', function() {
             nested: subSchema
           }, { strict: 'throw', useNestedStrict: true });
 
-          const Test = db.model('gh5144_2', schema);
+          const Test = db.model('Test', schema);
           const test = new Test({ name: 'Test1' });
           return co(function* () {
             yield test.save();
@@ -1619,7 +1624,7 @@ describe('Query', function() {
       assert.equal(q.options.readPreference.mode, 'secondary');
       assert.equal(q.options.readPreference.tags[0].dc, 'eu');
 
-      const Product = db.model('Product', 'Product_setOptions_test');
+      const Product = db.model('Product', productSchema);
       Product.create(
         {numbers: [3, 4, 5]},
         {strings: 'hi there'.split(' ')}, function(err, doc1, doc2) {
@@ -1683,7 +1688,7 @@ describe('Query', function() {
           name: String
         });
 
-        const MyModel = db.model('gh4839', schema);
+        const MyModel = db.model('Test', schema);
         const collation = { locale: 'en_US', strength: 1 };
 
         MyModel.create([{ name: 'a' }, { name: 'A' }]).
@@ -1712,28 +1717,33 @@ describe('Query', function() {
           catch(done);
       });
 
-      it('set on schema (gh-5295)', function(done) {
-        const schema = new Schema({
-          name: String
-        }, { collation: { locale: 'en_US', strength: 1 } });
+      it('set on schema (gh-5295)', function() {
+        return co(function*() {
+          yield db.db.collection('tests').drop().catch(err => {
+            if (err.message === 'ns not found') {
+              return;
+            }
+            throw err;
+          });
 
-        const MyModel = db.model('gh5295', schema);
+          const schema = new Schema({
+            name: String
+          }, { collation: { locale: 'en_US', strength: 1 } });
 
-        MyModel.create([{ name: 'a' }, { name: 'A' }]).
-          then(function() {
-            return MyModel.find({ name: 'a' });
-          }).
-          then(function(docs) {
-            assert.equal(docs.length, 2);
-            done();
-          }).
-          catch(done);
+          const MyModel = db.model('Test', schema, 'tests');
+
+          yield MyModel.create([{ name: 'a' }, { name: 'A' }]);
+
+          const docs = yield MyModel.find({ name: 'a' });
+
+          assert.equal(docs.length, 2);
+        });
       });
     });
 
     describe('gh-1950', function() {
       it.skip('ignores sort when passed to count', function(done) {
-        const Product = db.model('Product', 'Product_setOptions_test');
+        const Product = db.model('Product', productSchema);
         Product.find().sort({_id: 1}).count({}).exec(function(error) {
           assert.ifError(error);
           done();
@@ -1741,13 +1751,13 @@ describe('Query', function() {
       });
 
       it('ignores sort when passed to countDocuments', function() {
-        const Product = db.model('Product', 'Product_setOptions_test');
+        const Product = db.model('Product', productSchema);
         return Product.create({}).
           then(() => Product.find().sort({_id: 1}).countDocuments({}).exec());
       });
 
       it.skip('ignores count when passed to sort', function(done) {
-        const Product = db.model('Product', 'Product_setOptions_test');
+        const Product = db.model('Product', productSchema);
         Product.find().count({}).sort({_id: 1}).exec(function(error) {
           assert.ifError(error);
           done();
@@ -1756,7 +1766,7 @@ describe('Query', function() {
     });
 
     it('excludes _id when select false and inclusive mode (gh-3010)', function(done) {
-      const User = db.model('gh3010', {
+      const User = db.model('User', {
         _id: {
           select: false,
           type: Schema.Types.ObjectId,
@@ -1778,7 +1788,7 @@ describe('Query', function() {
     });
 
     it('doesnt reverse key order for update docs (gh-3215)', function(done) {
-      const Test = db.model('gh3215', {
+      const Test = db.model('Test', {
         arr: [{date: Date, value: Number}]
       });
 
@@ -1798,7 +1808,7 @@ describe('Query', function() {
 
     it('timestamps with $each (gh-4805)', function(done) {
       const nestedSchema = new Schema({ value: Number }, { timestamps: true });
-      const Test = db.model('gh4805', new Schema({
+      const Test = db.model('Test', new Schema({
         arr: [nestedSchema]
       }, { timestamps: true }));
 
@@ -1815,7 +1825,7 @@ describe('Query', function() {
     });
 
     it.skip('allows sort with count (gh-3914)', function(done) {
-      const Post = db.model('gh3914_0', {
+      const Post = db.model('Post', {
         title: String
       });
 
@@ -1827,7 +1837,7 @@ describe('Query', function() {
     });
 
     it.skip('allows sort with select (gh-3914)', function(done) {
-      const Post = db.model('gh3914_1', {
+      const Post = db.model('Post', {
         title: String
       });
 
@@ -1839,7 +1849,7 @@ describe('Query', function() {
     });
 
     it('handles nested $ (gh-3265)', function(done) {
-      const Post = db.model('gh3265', {
+      const Post = db.model('Post', {
         title: String,
         answers: [{
           details: String,
@@ -1872,7 +1882,7 @@ describe('Query', function() {
       });
       schema.index({ location: '2dsphere' });
 
-      const Model = db.model('gh4044', schema);
+      const Model = db.model('Test', schema);
 
       const query = {
         location:{
@@ -1896,7 +1906,7 @@ describe('Query', function() {
         name: String
       });
 
-      const MyModel = db.model('gh3825', schema);
+      const MyModel = db.model('Test', schema);
 
       const opts = { setDefaultsOnInsert: true, upsert: true };
       MyModel.updateOne({}, {}, opts, function(error) {
@@ -1920,7 +1930,7 @@ describe('Query', function() {
         return this.find({ name: name });
       };
 
-      const MyModel = db.model('gh3714', schema);
+      const MyModel = db.model('Test', schema);
 
       MyModel.create({ name: 'Val' }, function(error) {
         assert.ifError(error);
@@ -1938,7 +1948,7 @@ describe('Query', function() {
         name: String
       });
 
-      const MyModel = db.model('gh4378', schema);
+      const MyModel = db.model('Test', schema);
 
       MyModel.findOne('', function(error) {
         assert.ok(error);
@@ -1952,7 +1962,7 @@ describe('Query', function() {
         name: String,
         circle: Array
       });
-      const Area = db.model('gh4419', areaSchema);
+      const Area = db.model('Test', areaSchema);
 
       const placeSchema = new Schema({
         name: String,
@@ -1966,7 +1976,7 @@ describe('Query', function() {
         }
       });
       placeSchema.index({ geometry: '2dsphere' });
-      const Place = db.model('gh4419_0', placeSchema);
+      const Place = db.model('Place', placeSchema);
 
       const tromso = new Area({
         name: 'Tromso, Norway',
@@ -2006,7 +2016,7 @@ describe('Query', function() {
         createdAt: Date
       });
 
-      const M = db.model('gh4495', schema);
+      const M = db.model('Test', schema);
       const q = M.find({
         createdAt:{
           $not:{
@@ -2031,7 +2041,7 @@ describe('Query', function() {
         }
       });
 
-      const LineString = db.model('gh4408', lineStringSchema);
+      const LineString = db.model('Test', lineStringSchema);
 
       const ls = {
         name: 'test',
@@ -2070,7 +2080,7 @@ describe('Query', function() {
         test: String
       });
 
-      const Test = db.model('gh4592', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       Test.findOne({ test: { $not: /test/ } }, function(error) {
         assert.ifError(error);
@@ -2084,7 +2094,7 @@ describe('Query', function() {
           test: String
         });
 
-        const Test = db.model('gh6236', TestSchema);
+        const Test = db.model('Test', TestSchema);
 
         yield Test.create({});
 
@@ -2102,7 +2112,7 @@ describe('Query', function() {
         val: { type: String }
       });
 
-      const Test = db.model('gh5351', testSchema);
+      const Test = db.model('Test', testSchema);
       Test.create({ val: 'A string' }).
         then(function() {
           return Test.findOne({});
@@ -2134,7 +2144,7 @@ describe('Query', function() {
           }
         }
       });
-      const Model = db.model('gh6277', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.find({ strings: 'test' });
@@ -2151,7 +2161,7 @@ describe('Query', function() {
         test: String
       });
 
-      const Test = db.model('gh4933', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       Test.findOne({ test: { $not: { $exists: true } } }, function(error) {
         assert.ifError(error);
@@ -2173,7 +2183,7 @@ describe('Query', function() {
       });
       storySchema.index({ 'gallery.location': '2dsphere' });
 
-      const Story = db.model('gh5467', storySchema);
+      const Story = db.model('Story', storySchema);
 
       const q = {
         'gallery.location': {
@@ -2204,7 +2214,7 @@ describe('Query', function() {
         },
         arr: [Number]
       });
-      const Game = db.model('gh5450', gameSchema);
+      const Game = db.model('Test', gameSchema);
 
       Game.create({ name: 'Mass Effect', developer: 'BioWare', arr: [1, 2, 3] }, function(error) {
         assert.ifError(error);
@@ -2221,7 +2231,7 @@ describe('Query', function() {
     it('overwrites when passing an object when path already set to primitive (gh-6097)', function() {
       const schema = new mongoose.Schema({ status: String });
 
-      const Model = db.model('gh6097', schema);
+      const Model = db.model('Test', schema);
 
       return Model.
         where({ status: 'approved' }).
@@ -2237,7 +2247,7 @@ describe('Query', function() {
         sub: subSchema
       });
 
-      const Test = db.model('gh4937', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       const q = { test: { $exists: true }, sub: { $exists: false } };
       Test.findOne(q, function(error) {
@@ -2268,7 +2278,7 @@ describe('Query', function() {
         });
       });
 
-      const TestModel = db.model('gh5520', TestSchema);
+      const TestModel = db.model('Test', TestSchema);
 
       let numOps = ops.length;
 
@@ -2284,7 +2294,7 @@ describe('Query', function() {
     it('cast error with custom error (gh-5520)', function(done) {
       const TestSchema = new Schema({ name: Number });
 
-      const TestModel = db.model('gh5520_0', TestSchema);
+      const TestModel = db.model('Test', TestSchema);
 
       TestModel.
         find({ name: 'not a number' }).
@@ -2312,7 +2322,7 @@ describe('Query', function() {
         });
       });
 
-      const M = db.model('gh4428', schema);
+      const M = db.model('Test', schema);
 
       M.create({ name: 'test' }, function(error, doc) {
         assert.ifError(error);
@@ -2341,7 +2351,7 @@ describe('Query', function() {
         child: ChildSchema,
         child2: ChildSchema
       });
-      const Parent = db.model('gh5603', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
       const ogParent = new Parent();
       ogParent.child = { field: 'test' };
       ogParent.child2 = { field: 'test' };
@@ -2364,7 +2374,7 @@ describe('Query', function() {
         throw new Error('Failed! ' + (count++));
       });
 
-      const TestModel = db.model('gh5592', TestSchema);
+      const TestModel = db.model('Test', TestSchema);
 
       const docs = [];
       for (let i = 0; i < 10; ++i) {
@@ -2386,7 +2396,7 @@ describe('Query', function() {
       const schema = new mongoose.Schema({
         email: String
       });
-      const M = db.model('gh1698', schema);
+      const M = db.model('Test', schema);
 
       M.find(42, function(error) {
         assert.ok(error);
@@ -2410,7 +2420,7 @@ describe('Query', function() {
       it('throw on sync exceptions in callbacks (gh-6178)', function(done) {
         const async = require('async');
         const schema = new Schema({});
-        const Test = db.model('gh6178', schema);
+        const Test = db.model('Test', schema);
 
         process.once('uncaughtException', err => {
           assert.equal(err.message, 'woops');
@@ -2435,7 +2445,7 @@ describe('Query', function() {
 
     it.skip('set overwrite after update() (gh-4740)', function() {
       const schema = new Schema({ name: String, age: Number });
-      const User = db.model('4740', schema);
+      const User = db.model('User', schema);
 
       return co(function*() {
         yield User.create({ name: 'Bar', age: 29 });
@@ -2457,7 +2467,7 @@ describe('Query', function() {
         email: String
       });
 
-      const model = db.model('gh5812', schema);
+      const model = db.model('Test', schema);
       const bigData = new Array(800000);
 
       for (let i = 0; i < bigData.length; ++i) {
@@ -2480,7 +2490,7 @@ describe('Query', function() {
         n: Number
       });
 
-      const Model = db.model('gh6271', schema);
+      const Model = db.model('Test', schema);
 
       Model.create({ n: 0 }, (err, doc) => {
         assert.ifError(err);
@@ -2498,7 +2508,7 @@ describe('Query', function() {
       return co(function*() {
         const schema = new mongoose.Schema({ n: Number });
 
-        const Model = db.model('gh6625', schema);
+        const Model = db.model('Test', schema);
 
         yield Model.create({ n: 42 });
 
@@ -2536,7 +2546,7 @@ describe('Query', function() {
         activitySchema.path('owner').discriminator('user', userOwnerSchema);
         activitySchema.path('owner').discriminator('tag', tagOwnerSchema);
 
-        const Activity = db.model('gh6027', activitySchema);
+        const Activity = db.model('Test', activitySchema);
 
         yield Activity.insertMany([
           {
@@ -2585,7 +2595,7 @@ describe('Query', function() {
         activitySchema.path('owner').discriminator('user', userOwnerSchema);
         activitySchema.path('owner').discriminator('tag', tagOwnerSchema);
 
-        const Activity = db.model('gh6027_0', activitySchema);
+        const Activity = db.model('Test', activitySchema);
 
         yield Activity.insertMany([
           {
@@ -2627,7 +2637,7 @@ describe('Query', function() {
 
         OrderSchema.path('lines').discriminator('listing', ListingLineSchema);
 
-        const Order = db.model('gh7449', OrderSchema);
+        const Order = db.model('Order', OrderSchema);
 
         yield Order.create({ lines: { kind: 'listing', sellerId: 42 } });
 
@@ -2656,7 +2666,7 @@ describe('Query', function() {
         }
       });
 
-      const Area = db.model('gh4392_0', areaSchema);
+      const Area = db.model('Test', areaSchema);
 
       const observationSchema = new Schema({
         geometry: {
@@ -2673,7 +2683,7 @@ describe('Query', function() {
       });
       observationSchema.index({ geometry: '2dsphere' });
 
-      const Observation = db.model('gh4392_1', observationSchema);
+      const Observation = db.model('Test1', observationSchema);
 
       Observation.on('index', function(error) {
         assert.ifError(error);
@@ -2725,7 +2735,8 @@ describe('Query', function() {
         dependents: [String]
       });
 
-      const m = db.model('gh3256', PersonSchema, 'gh3256');
+      db.deleteModel(/Person/);
+      const m = db.model('Person', PersonSchema);
 
       const obj = {
         name: 'John',
@@ -2742,7 +2753,8 @@ describe('Query', function() {
           salary: {type: Number, default: 25000}
         });
 
-        MyModel = db.model('gh3256-salary', PersonSchema, 'gh3256');
+        db.deleteModel(/Person/);
+        MyModel = db.model('Person', PersonSchema);
 
         done();
       });
@@ -2783,7 +2795,7 @@ describe('Query', function() {
           price: Number
         });
 
-        const Model = db.model('gh6323', priceSchema);
+        const Model = db.model('Test', priceSchema);
 
         const tests = [];
 
@@ -2810,7 +2822,7 @@ describe('Query', function() {
 
   describe('setQuery', function() {
     it('replaces existing query with new value (gh-6854)', function() {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       q.where('userName').exists();
       q.setQuery({ a: 1 });
       assert.deepStrictEqual(q._conditions, { a: 1 });
@@ -2818,7 +2830,7 @@ describe('Query', function() {
   });
 
   it('map (gh-7142)', function() {
-    const Model = db.model('gh7142', new Schema({ name: String }));
+    const Model = db.model('Test', new Schema({ name: String }));
 
     return co(function*() {
       yield Model.create({ name: 'test' });
@@ -2836,7 +2848,7 @@ describe('Query', function() {
     let Model;
 
     before(function() {
-      Model = db.model('gh6841', new Schema({ name: String }));
+      Model = db.model('Test', new Schema({ name: String }));
     });
 
     beforeEach(function() {
@@ -3036,7 +3048,7 @@ describe('Query', function() {
           docs.push(doc);
           next();
         });
-        const Model = db.model('gh7280', schema);
+        const Model = db.model('Test', schema);
 
         yield Model.create({ name: 'Test' });
 
@@ -3065,7 +3077,7 @@ describe('Query', function() {
           then(() => null, err => err);
         assert.equal(err.name, 'DocumentNotFoundError', err.stack);
         assert.ok(err.message.indexOf('na') !== -1, err.message);
-        assert.ok(err.message.indexOf('gh6841') !== -1, err.message);
+        assert.ok(err.message.indexOf('"Test"') !== -1, err.message);
         assert.deepEqual(err.filter, { name: 'na' });
       });
     });
@@ -3078,7 +3090,7 @@ describe('Query', function() {
         assert.deepStrictEqual(this.getPopulatedPaths(), []);
       });
 
-      const Model = db.model('gh6677_model', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.findOne({});
@@ -3090,15 +3102,15 @@ describe('Query', function() {
       const schema = new Schema({
         other: {
           type: Schema.Types.ObjectId,
-          ref: 'gh6677_other'
+          ref: 'Other'
         }
       });
       schema.pre('findOne', function() {
         assert.deepStrictEqual(this.getPopulatedPaths(), ['other']);
       });
 
-      const Other = db.model('gh6677_other', otherSchema);
-      const Test = db.model('gh6677_test', schema);
+      const Other = db.model('Other', otherSchema);
+      const Test = db.model('Test', schema);
 
       const other = new Other({ name: 'one' });
       const test = new Test({ other: other._id });
@@ -3111,10 +3123,10 @@ describe('Query', function() {
     });
 
     it('returns deep populated paths (gh-7757)', function() {
-      db.model('gh7757_L3', new Schema({ name: String }));
-      db.model('gh7757_L2', new Schema({ level3: { type: String, ref: 'L3' } }));
-      const L1 = db.model('gh7757_L1',
-        new Schema({ level1: { type: String, ref: 'L2' } }));
+      db.model('Test3', new Schema({ name: String }));
+      db.model('Test2', new Schema({ level3: { type: String, ref: 'Test3' } }));
+      const L1 = db.model('Test',
+        new Schema({ level1: { type: String, ref: 'Test2' } }));
 
       const query = L1.find().populate({
         path: 'level1',
@@ -3133,7 +3145,7 @@ describe('Query', function() {
 
   describe('setUpdate', function() {
     it('replaces existing update doc with new value', function() {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       q.set('testing', '123');
       q.setUpdate({ $set: { newPath: 'newValue' } });
       assert.strictEqual(q._update.$set.testing, undefined);
@@ -3143,28 +3155,28 @@ describe('Query', function() {
 
   describe('get() (gh-7312)', function() {
     it('works with using $set', function() {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       q.updateOne({}, { $set: { name: 'Jean-Luc Picard' } });
 
       assert.equal(q.get('name'), 'Jean-Luc Picard');
     });
 
     it('works with $set syntactic sugar', function() {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       q.updateOne({}, { name: 'Jean-Luc Picard' });
 
       assert.equal(q.get('name'), 'Jean-Luc Picard');
     });
 
     it('works with mixed', function() {
-      const q = new Query({}, {}, null, p1.collection);
+      const q = new Query({}, {}, null);
       q.updateOne({}, { name: 'Jean-Luc Picard', $set: { age: 59 } });
 
       assert.equal(q.get('name'), 'Jean-Luc Picard');
     });
 
     it('$set overwrites existing', function() {
-      const M = db.model('gh7312', new Schema({ name: String }));
+      const M = db.model('Test', new Schema({ name: String }));
       const q = M.updateOne({}, {
         name: 'Jean-Luc Picard',
         $set: { name: 'William Riker' }
@@ -3181,7 +3193,7 @@ describe('Query', function() {
   it('allows skipping timestamps in updateOne() (gh-6980)', function() {
     const schema = new Schema({ name: String }, { timestamps: true });
 
-    const M = db.model('gh6980', schema);
+    const M = db.model('Test', schema);
 
     return co(function*() {
       const doc = yield M.create({ name: 'foo' });
@@ -3209,7 +3221,7 @@ describe('Query', function() {
       // timestamps: true,
       versionKey: false
     });
-    const Parent = db.model('gh4412', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
       let doc = yield Parent.create({ child: { name: 'foo' } });
@@ -3253,7 +3265,7 @@ describe('Query', function() {
       });
       const parentSchema = new Schema({ children: [childSchema] }, {
         versionKey: false });
-      Parent = db.model('gh4412_arr', parentSchema);
+      Parent = db.model('Parent', parentSchema);
     });
 
     it('$set nested property with numeric position', function() {
@@ -3334,7 +3346,7 @@ describe('Query', function() {
           timestamps: true
         });
 
-        const Test = db.model('gh7106', schema);
+        const Test = db.model('Test', schema);
 
         const cond = { arr: { $elemMatch: { name: 'abc' } } };
         const set = { $set: { 'arr.$.subArr': [{ x: 'b' }] } };
@@ -3361,7 +3373,7 @@ describe('Query', function() {
       nested: { path: String }
     }, { strictQuery: 'throw' });
 
-    const Model = db.model('gh4136', modelSchema);
+    const Model = db.model('Test', modelSchema);
 
     return co(function*() {
       // `find()` on a top-level path not in the schema
@@ -3385,7 +3397,7 @@ describe('Query', function() {
     const modelSchema = new Schema({ field: Number }, { strictQuery: true });
 
     return co(function*() {
-      const Model = db.model('gh6032', modelSchema);
+      const Model = db.model('Test', modelSchema);
 
       yield Model.create({ field: 1 });
 
@@ -3402,7 +3414,7 @@ describe('Query', function() {
     });
 
     return co(function*() {
-      const Model = db.model('gh7182', schema);
+      const Model = db.model('Test', schema);
 
       yield Model.create({ kind: 'test' });
       yield Model.updateOne({}, { $unset: { hasDefault: 1 } });
@@ -3413,7 +3425,7 @@ describe('Query', function() {
   });
 
   it('merging objectids with where() (gh-7360)', function() {
-    const Test = db.model('gh7360', new Schema({}));
+    const Test = db.model('Test', new Schema({}));
 
     return Test.create({}).
       then(doc => Test.find({ _id: doc._id.toString() }).where({ _id: doc._id })).
@@ -3421,7 +3433,7 @@ describe('Query', function() {
   });
 
   it('maxTimeMS() (gh-7254)', function() {
-    const Model = db.model('gh7254', new Schema({}));
+    const Model = db.model('Test', new Schema({}));
 
     return co(function*() {
       yield Model.create({});
@@ -3437,7 +3449,7 @@ describe('Query', function() {
   it('connection-level maxTimeMS() (gh-4066)', function() {
     db.options = db.options || {};
     db.options.maxTimeMS = 10;
-    const Model = db.model('gh4066_conn', new Schema({}));
+    const Model = db.model('Test', new Schema({}));
 
     return co(function*() {
       yield Model.create({});
@@ -3453,7 +3465,7 @@ describe('Query', function() {
   it('mongoose-level maxTimeMS() (gh-4066)', function() {
     db.base.options = db.base.options || {};
     db.base.options.maxTimeMS = 10;
-    const Model = db.model('gh4066_global', new Schema({}));
+    const Model = db.model('Test', new Schema({}));
 
     return co(function*() {
       yield Model.create({});
@@ -3467,7 +3479,7 @@ describe('Query', function() {
   });
 
   it('throws error with updateOne() and overwrite (gh-7475)', function() {
-    const Model = db.model('gh7475', new Schema({ name: String }));
+    const Model = db.model('Test', Schema({ name: String }));
 
     return Model.updateOne({}, { name: 'bar' }, { overwrite: true }).then(
       () => { throw new Error('Should have failed'); },
@@ -3478,7 +3490,7 @@ describe('Query', function() {
   it('sets deletedCount on result of remove() (gh-7629)', function() {
     const schema = new Schema({ name: String });
 
-    const Model = db.model('gh7629', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.create({ name: 'foo' });
@@ -3493,16 +3505,16 @@ describe('Query', function() {
 
   describe('merge()', function() {
     it('copies populate() (gh-1790)', function() {
-      const Car = db.model('gh1790_Car', {
+      const Car = db.model('Car', {
         color: String,
         model: String,
         owner: {
           type: Schema.Types.ObjectId,
-          ref: 'gh1790_Person'
+          ref: 'Person'
         }
       });
 
-      const Person = db.model('gh1790_Person', {
+      const Person = db.model('Person', {
         name: String
       });
 
@@ -3541,7 +3553,7 @@ describe('Query', function() {
         this.set('password', 'encryptedpassword');
       });
 
-      const M = db.model('gh7984', schema);
+      const M = db.model('Test', schema);
 
       const opts = { runValidators: true, upsert: true, new: true };
       return M.findOneAndUpdate({}, { password: '6chars' }, opts).then(doc => {
@@ -3557,7 +3569,7 @@ describe('Query', function() {
         throw new Error('Oops!');
       });
       const contactSchema = Schema({ addresses: [addressSchema] });
-      const Contact = db.model('gh7187', contactSchema);
+      const Contact = db.model('Test', contactSchema);
 
       const update = { addresses: [{ countryId: 'foo' }] };
       return Contact.updateOne({}, update, { runValidators: true }).then(
@@ -3572,7 +3584,7 @@ describe('Query', function() {
 
   it('query with top-level _bsontype (gh-8222) (gh-8268)', function() {
     const userSchema = Schema({ token: String });
-    const User = db.model('gh8222', userSchema);
+    const User = db.model('Test', userSchema);
 
     return co(function*() {
       const original = yield User.create({ token: 'rightToken' });

From 73cba7d17a987e7b75f8ca30a055727af8878b5c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 14:45:06 -0500
Subject: [PATCH 0369/2348] test: fix tests re: #8481 refactor

---
 test/query.test.js | 43 +++++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index f688b431d23..e29c218b5f8 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1113,33 +1113,31 @@ describe('Query', function() {
   });
 
   describe('deleteOne/deleteMany', function() {
-    it('handles deleteOne', function(done) {
+    it('handles deleteOne', function() {
       const M = db.model('Person', new Schema({ name: 'String' }));
-      M.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
-        assert.ifError(error);
-        M.deleteOne({ name: /Stark/ }, function(error) {
-          assert.ifError(error);
-          M.estimatedDocumentCount(function(error, count) {
-            assert.ifError(error);
-            assert.equal(count, 1);
-            done();
-          });
-        });
+
+      return co(function*() {
+        yield M.deleteMany({});
+        yield M.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }]);
+
+        yield M.deleteOne({ name: /Stark/ });
+
+        const count = yield M.countDocuments();
+        assert.equal(count, 1);
       });
     });
 
-    it('handles deleteMany', function(done) {
+    it('handles deleteMany', function() {
       const M = db.model('Person', new Schema({ name: 'String' }));
-      M.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }], function(error) {
-        assert.ifError(error);
-        M.deleteMany({ name: /Stark/ }, function(error) {
-          assert.ifError(error);
-          M.countDocuments({}, function(error, count) {
-            assert.ifError(error);
-            assert.equal(count, 0);
-            done();
-          });
-        });
+
+      return co(function*() {
+        yield M.deleteMany({});
+        yield M.create([{ name: 'Eddard Stark' }, { name: 'Robb Stark' }]);
+
+        yield M.deleteMany({ name: /Stark/ });
+
+        const count = yield M.countDocuments();
+        assert.equal(count, 0);
       });
     });
   });
@@ -2848,6 +2846,7 @@ describe('Query', function() {
     let Model;
 
     before(function() {
+      db.deleteModel(/Test/);
       Model = db.model('Test', new Schema({ name: String }));
     });
 

From 3759747b7493724c7bf08824f1254925f9cbb745 Mon Sep 17 00:00:00 2001
From: ntsekouras <ntsekouras@outlook.com>
Date: Tue, 14 Jan 2020 22:44:14 +0200
Subject: [PATCH 0370/2348] fix-8234

---
 lib/model.js       | 15 ++++++++++-----
 test/model.test.js | 47 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index f0b46984a6b..5c335cf11a0 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3252,16 +3252,15 @@ Model.$__insertMany = function(arr, options, callback) {
   const limit = get(options, 'limit', 1000);
   const rawResult = get(options, 'rawResult', false);
   const ordered = get(options, 'ordered', true);
+  const lean = get(options, 'lean', false);
 
   if (!Array.isArray(arr)) {
     arr = [arr];
   }
 
-  const toExecute = [];
   const validationErrors = [];
-
-  arr.forEach(function(doc) {
-    toExecute.push(function(callback) {
+  const toExecute = arr.map(doc =>
+    callback => {
       if (!(doc instanceof _this)) {
         try {
           doc = new _this(doc);
@@ -3272,6 +3271,13 @@ Model.$__insertMany = function(arr, options, callback) {
       if (options.session != null) {
         doc.$session(options.session);
       }
+      // If option `lean` is set to true bypass validation
+      if (lean) {
+        // we have to execute callback at the nextTick to be compatible
+        // with parallelLimit, as `results` variable has TDZ issue if we
+        // execute the callback synchronously
+        return process.nextTick(() => callback(null, doc));
+      }
       doc.validate({ __noPromise: true }, function(error) {
         if (error) {
           // Option `ordered` signals that insert should be continued after reaching
@@ -3286,7 +3292,6 @@ Model.$__insertMany = function(arr, options, callback) {
         callback(null, doc);
       });
     });
-  });
 
   parallelLimit(toExecute, limit, function(error, docs) {
     if (error) {
diff --git a/test/model.test.js b/test/model.test.js
index ab0610e6ed2..719f9d7a6fe 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4661,6 +4661,53 @@ describe('Model', function() {
       }
     });
 
+    describe('insertMany() lean option to bypass validation (gh-8234)', () => {
+      const gh8234Schema = new Schema({
+        name: String,
+        age: { type: Number, required: true }
+      });
+      const arrGh8234 = [{ name: 'Rigas' }, { name: 'Tonis', age: 9 }];
+      let Gh8234;
+      before('init model', () => {
+        Gh8234 = db.model('gh8234', gh8234Schema);
+      });
+      afterEach('delete inserted data', function() {
+        return Gh8234.deleteMany({});
+      });
+
+      it('insertMany() should bypass validation if lean option set to `true`', (done) => {
+        Gh8234.insertMany(arrGh8234, { lean: true }, (error, docs) => {
+          assert.ifError(error);
+          assert.equal(docs.length, 2);
+          Gh8234.find({}, (error, docs) => {
+            assert.ifError(error);
+            assert.equal(docs.length, 2);
+            assert.equal(arrGh8234[0].age, undefined);
+            assert.equal(arrGh8234[1].age, 9);
+            done();
+          });
+        });
+      });
+
+      it('insertMany() should validate if lean option not set', (done) => {
+        Gh8234.insertMany(arrGh8234, (error) => {
+          assert.ok(error);
+          assert.equal(error.name, 'ValidationError');
+          assert.equal(error.errors.age.kind, 'required');
+          done();
+        });
+      });
+
+      it('insertMany() should validate if lean option set to `false`', (done) => {
+        Gh8234.insertMany(arrGh8234, { lean: false }, (error) => {
+          assert.ok(error);
+          assert.equal(error.name, 'ValidationError');
+          assert.equal(error.errors.age.kind, 'required');
+          done();
+        });
+      });
+    });
+
     it('insertMany() ordered option for validation errors (gh-5068)', function(done) {
       start.mongodVersion(function(err, version) {
         if (err) {

From 246cb60fd8e954b5f54bed6b9e2b5a4a89b62602 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 17:23:19 -0500
Subject: [PATCH 0371/2348] test: clean up unnecessary params to Query
 constructor re: #8481

---
 test/query.test.js | 247 +++++++++++++++++++++++----------------------
 1 file changed, 124 insertions(+), 123 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index e29c218b5f8..35117d5b2f1 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -64,7 +64,7 @@ describe('Query', function() {
   describe('constructor', function() {
     it('should not corrupt options', function(done) {
       const opts = {};
-      const query = new Query({}, opts, null);
+      const query = new Query({}, opts);
       assert.notEqual(opts, query._mongooseOptions);
       done();
     });
@@ -72,14 +72,14 @@ describe('Query', function() {
 
   describe('select', function() {
     it('(object)', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.select({a: 1, b: 1, c: 0});
       assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
       done();
     });
 
     it('(string)', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.select(' a  b -c ');
       assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
       done();
@@ -87,14 +87,14 @@ describe('Query', function() {
 
     it('("a","b","c")', function(done) {
       assert.throws(function() {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.select('a', 'b', 'c');
       }, /Invalid select/);
       done();
     });
 
     it('should not overwrite fields set in prior calls', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.select('a');
       assert.deepEqual(query._fields, {a: 1});
       query.select('b');
@@ -109,13 +109,13 @@ describe('Query', function() {
 
   describe('projection() (gh-7384)', function() {
     it('gets current projection', function() {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.select('a');
       assert.deepEqual(query.projection(), { a: 1 });
     });
 
     it('overwrites current projection', function() {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.select('a');
       assert.deepEqual(query.projection({ b: 1 }), { b: 1 });
       assert.deepEqual(query.projection(), { b: 1 });
@@ -124,7 +124,7 @@ describe('Query', function() {
 
   describe('where', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('name', 'guillermo');
       assert.deepEqual(query._conditions, {name: 'guillermo'});
       query.where('a');
@@ -133,7 +133,7 @@ describe('Query', function() {
       done();
     });
     it('throws if non-string or non-object path is passed', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       assert.throws(function() {
         query.where(50);
       });
@@ -143,7 +143,7 @@ describe('Query', function() {
       done();
     });
     it('does not throw when 0 args passed', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       assert.doesNotThrow(function() {
         query.where();
       });
@@ -153,7 +153,7 @@ describe('Query', function() {
 
   describe('equals', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('name').equals('guillermo');
       assert.deepEqual(query._conditions, {name: 'guillermo'});
       done();
@@ -162,13 +162,13 @@ describe('Query', function() {
 
   describe('gte', function() {
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.gte('age', 18);
       assert.deepEqual(query._conditions, {age: {$gte: 18}});
       done();
     });
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').gte(18);
       assert.deepEqual(query._conditions, {age: {$gte: 18}});
       done();
@@ -177,13 +177,13 @@ describe('Query', function() {
 
   describe('gt', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').gt(17);
       assert.deepEqual(query._conditions, {age: {$gt: 17}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.gt('age', 17);
       assert.deepEqual(query._conditions, {age: {$gt: 17}});
       done();
@@ -192,13 +192,13 @@ describe('Query', function() {
 
   describe('lte', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').lte(65);
       assert.deepEqual(query._conditions, {age: {$lte: 65}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.lte('age', 65);
       assert.deepEqual(query._conditions, {age: {$lte: 65}});
       done();
@@ -207,13 +207,13 @@ describe('Query', function() {
 
   describe('lt', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').lt(66);
       assert.deepEqual(query._conditions, {age: {$lt: 66}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.lt('age', 66);
       assert.deepEqual(query._conditions, {age: {$lt: 66}});
       done();
@@ -223,7 +223,7 @@ describe('Query', function() {
   describe('combined', function() {
     describe('lt and gt', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('age').lt(66).gt(17);
         assert.deepEqual(query._conditions, {age: {$lt: 66, $gt: 17}});
         done();
@@ -233,7 +233,7 @@ describe('Query', function() {
 
   describe('tl on one path and gt on another', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query
         .where('age').lt(66)
         .where('height').gt(5);
@@ -244,13 +244,13 @@ describe('Query', function() {
 
   describe('ne', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').ne(21);
       assert.deepEqual(query._conditions, {age: {$ne: 21}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.ne('age', 21);
       assert.deepEqual(query._conditions, {age: {$ne: 21}});
       done();
@@ -259,25 +259,25 @@ describe('Query', function() {
 
   describe('in', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').in([21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$in: [21, 25, 30]}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.in('age', [21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$in: [21, 25, 30]}});
       done();
     });
     it('where a non-array value no via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.in('age', 21);
       assert.deepEqual(query._conditions, {age: {$in: 21}});
       done();
     });
     it('where a non-array value via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').in(21);
       assert.deepEqual(query._conditions, {age: {$in: 21}});
       done();
@@ -286,25 +286,25 @@ describe('Query', function() {
 
   describe('nin', function() {
     it('with 1 arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').nin([21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$nin: [21, 25, 30]}});
       done();
     });
     it('with 2 args', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.nin('age', [21, 25, 30]);
       assert.deepEqual(query._conditions, {age: {$nin: [21, 25, 30]}});
       done();
     });
     it('with a non-array value not via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.nin('age', 21);
       assert.deepEqual(query._conditions, {age: {$nin: 21}});
       done();
     });
     it('with a non-array value via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').nin(21);
       assert.deepEqual(query._conditions, {age: {$nin: 21}});
       done();
@@ -313,25 +313,25 @@ describe('Query', function() {
 
   describe('mod', function() {
     it('not via where, where [a, b] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.mod('age', [5, 2]);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
     });
     it('not via where, where a and b params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.mod('age', 5, 2);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
     });
     it('via where, where [a, b] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').mod([5, 2]);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
     });
     it('via where, where a and b params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('age').mod(5, 2);
       assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
       done();
@@ -340,37 +340,37 @@ describe('Query', function() {
 
   describe('near', function() {
     it('via where, where { center :[lat, long]} param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').near({center: [40, -72]});
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').near([40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').near(40, -72);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('not via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.near('checkin', [40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('not via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.near('checkin', 40, -72);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
       done();
     });
     it('via where, where GeoJSON param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('numbers').near({center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {numbers: {$near: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       assert.doesNotThrow(function() {
@@ -379,7 +379,7 @@ describe('Query', function() {
       done();
     });
     it('with path, where GeoJSON param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.near('loc', {center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {loc: {$near: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       done();
@@ -388,39 +388,39 @@ describe('Query', function() {
 
   describe('nearSphere', function() {
     it('via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').nearSphere([40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
     it('via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').nearSphere(40, -72);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
     it('not via where, where [lat, long] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.nearSphere('checkin', [40, -72]);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
     it('not via where, where lat and long params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.nearSphere('checkin', 40, -72);
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
       done();
     });
 
     it('via where, with object', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').nearSphere({center: [20, 23], maxDistance: 2});
       assert.deepEqual(query._conditions, {checkin: {$nearSphere: [20, 23], $maxDistance: 2}});
       done();
     });
 
     it('via where, where GeoJSON param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('numbers').nearSphere({center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {numbers: {$nearSphere: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       assert.doesNotThrow(function() {
@@ -430,7 +430,7 @@ describe('Query', function() {
     });
 
     it('with path, with GeoJSON', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.nearSphere('numbers', {center: {type: 'Point', coordinates: [40, -72]}});
       assert.deepEqual(query._conditions, {numbers: {$nearSphere: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
       assert.doesNotThrow(function() {
@@ -442,7 +442,7 @@ describe('Query', function() {
 
   describe('maxDistance', function() {
     it('via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('checkin').near([40, -72]).maxDistance(1);
       assert.deepEqual(query._conditions, {checkin: {$near: [40, -72], $maxDistance: 1}});
       done();
@@ -452,7 +452,7 @@ describe('Query', function() {
   describe('within', function() {
     describe('box', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('gps').within().box({ll: [5, 25], ur: [10, 30]});
         const match = {gps: {$within: {$box: [[5, 25], [10, 30]]}}};
         if (Query.use$geoWithin) {
@@ -463,7 +463,7 @@ describe('Query', function() {
         done();
       });
       it('via where, no object', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('gps').within().box([5, 25], [10, 30]);
         const match = {gps: {$within: {$box: [[5, 25], [10, 30]]}}};
         if (Query.use$geoWithin) {
@@ -477,7 +477,7 @@ describe('Query', function() {
 
     describe('center', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('gps').within().center({center: [5, 25], radius: 5});
         const match = {gps: {$within: {$center: [[5, 25], 5]}}};
         if (Query.use$geoWithin) {
@@ -491,7 +491,7 @@ describe('Query', function() {
 
     describe('centerSphere', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('gps').within().centerSphere({center: [5, 25], radius: 5});
         const match = {gps: {$within: {$centerSphere: [[5, 25], 5]}}};
         if (Query.use$geoWithin) {
@@ -505,7 +505,7 @@ describe('Query', function() {
 
     describe('polygon', function() {
       it('via where', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('gps').within().polygon({a: {x: 10, y: 20}, b: {x: 15, y: 25}, c: {x: 20, y: 20}});
         const match = {gps: {$within: {$polygon: [{a: {x: 10, y: 20}, b: {x: 15, y: 25}, c: {x: 20, y: 20}}]}}};
         if (Query.use$geoWithin) {
@@ -520,26 +520,26 @@ describe('Query', function() {
 
   describe('exists', function() {
     it('0 args via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('username').exists();
       assert.deepEqual(query._conditions, {username: {$exists: true}});
       done();
     });
     it('1 arg via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('username').exists(false);
       assert.deepEqual(query._conditions, {username: {$exists: false}});
       done();
     });
     it('where 1 argument not via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.exists('username');
       assert.deepEqual(query._conditions, {username: {$exists: true}});
       done();
     });
 
     it('where 2 args not via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.exists('username', false);
       assert.deepEqual(query._conditions, {username: {$exists: false}});
       done();
@@ -548,13 +548,13 @@ describe('Query', function() {
 
   describe('all', function() {
     it('via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('pets').all(['dog', 'cat', 'ferret']);
       assert.deepEqual(query._conditions, {pets: {$all: ['dog', 'cat', 'ferret']}});
       done();
     });
     it('not via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.all('pets', ['dog', 'cat', 'ferret']);
       assert.deepEqual(query._conditions, {pets: {$all: ['dog', 'cat', 'ferret']}});
       done();
@@ -563,14 +563,14 @@ describe('Query', function() {
 
   describe('find', function() {
     it('strict array equivalence condition v', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.find({pets: ['dog', 'cat', 'ferret']});
       assert.deepEqual(query._conditions, {pets: ['dog', 'cat', 'ferret']});
       done();
     });
     it('with no args', function(done) {
       let threw = false;
-      const q = new Query({}, {}, null);
+      const q = new Query({});
 
       try {
         q.find();
@@ -583,7 +583,7 @@ describe('Query', function() {
     });
 
     it('works with overwriting previous object args (1176)', function(done) {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       assert.doesNotThrow(function() {
         q.find({age: {$lt: 30}});
         q.find({age: 20}); // overwrite
@@ -595,13 +595,13 @@ describe('Query', function() {
 
   describe('size', function() {
     it('via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').size(5);
       assert.deepEqual(query._conditions, {collection: {$size: 5}});
       done();
     });
     it('not via where', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.size('collection', 5);
       assert.deepEqual(query._conditions, {collection: {$size: 5}});
       done();
@@ -610,73 +610,73 @@ describe('Query', function() {
 
   describe('slice', function() {
     it('where and positive limit param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice(5);
       assert.deepEqual(query._fields, {collection: {$slice: 5}});
       done();
     });
     it('where just negative limit param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice(-5);
       assert.deepEqual(query._fields, {collection: {$slice: -5}});
       done();
     });
     it('where [skip, limit] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice([14, 10]); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('where skip and limit params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice(14, 10); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('where just positive limit param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice(5);
       assert.deepEqual(query._fields, {collection: {$slice: 5}});
       done();
     });
     it('where just negative limit param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice(-5);
       assert.deepEqual(query._fields, {collection: {$slice: -5}});
       done();
     });
     it('where the [skip, limit] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice([14, 10]); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('where the skip and limit params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.where('collection').slice(14, 10); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('not via where, with just positive limit param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.slice('collection', 5);
       assert.deepEqual(query._fields, {collection: {$slice: 5}});
       done();
     });
     it('not via where, where just negative limit param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.slice('collection', -5);
       assert.deepEqual(query._fields, {collection: {$slice: -5}});
       done();
     });
     it('not via where, where [skip, limit] param', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.slice('collection', [14, 10]); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
     });
     it('not via where, where skip and limit params', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.slice('collection', 14, 10); // Return the 15th through 25th
       assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
       done();
@@ -686,13 +686,13 @@ describe('Query', function() {
   describe('elemMatch', function() {
     describe('not via where', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.elemMatch('comments', {author: 'bnoguchi', votes: {$gte: 5}});
         assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
         done();
       });
       it('where block notation', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.elemMatch('comments', function(elem) {
           elem.where('author', 'bnoguchi');
           elem.where('votes').gte(5);
@@ -703,13 +703,13 @@ describe('Query', function() {
     });
     describe('via where', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('comments').elemMatch({author: 'bnoguchi', votes: {$gte: 5}});
         assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
         done();
       });
       it('where block notation', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.where('comments').elemMatch(function(elem) {
           elem.where('author', 'bnoguchi');
           elem.where('votes').gte(5);
@@ -722,7 +722,7 @@ describe('Query', function() {
 
   describe('$where', function() {
     it('function arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
 
       function filter() {
         return this.lastName === this.firstName;
@@ -733,7 +733,7 @@ describe('Query', function() {
       done();
     });
     it('string arg', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.$where('this.lastName === this.firstName');
       assert.deepEqual(query._conditions, {$where: 'this.lastName === this.firstName'});
       done();
@@ -742,7 +742,7 @@ describe('Query', function() {
 
   describe('limit', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.limit(5);
       assert.equal(query.options.limit, 5);
       done();
@@ -751,7 +751,7 @@ describe('Query', function() {
 
   describe('skip', function() {
     it('works', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       query.skip(9);
       assert.equal(query.options.skip, 9);
       done();
@@ -760,21 +760,21 @@ describe('Query', function() {
 
   describe('sort', function() {
     it('works', function(done) {
-      let query = new Query({}, {}, null);
+      let query = new Query({});
       query.sort('a -c b');
       assert.deepEqual(query.options.sort, {a: 1, c: -1, b: 1});
-      query = new Query({}, {}, null);
+      query = new Query({});
       query.sort({a: 1, c: -1, b: 'asc', e: 'descending', f: 'ascending'});
       assert.deepEqual(query.options.sort, {a: 1, c: -1, b: 1, e: -1, f: 1});
 
       if (typeof global.Map !== 'undefined') {
-        query = new Query({}, {}, null);
+        query = new Query({});
         query.sort(new global.Map().set('a', 1).set('b', 1));
         assert.equal(query.options.sort.get('a'), 1);
         assert.equal(query.options.sort.get('b'), 1);
       }
 
-      query = new Query({}, {}, null);
+      query = new Query({});
       let e;
 
       try {
@@ -835,7 +835,7 @@ describe('Query', function() {
 
   describe('populate', function() {
     it('converts to PopulateOptions objects', function(done) {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       const o = {
         path: 'yellow.brick',
         match: {bricks: {$lt: 1000}},
@@ -850,7 +850,7 @@ describe('Query', function() {
     });
 
     it('overwrites duplicate paths', function(done) {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       let o = {
         path: 'yellow.brick',
         match: {bricks: {$lt: 1000}},
@@ -871,7 +871,7 @@ describe('Query', function() {
     });
 
     it('accepts space delimited strings', function(done) {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       q.populate('yellow.brick dirt');
       assert.equal(Object.keys(q._mongooseOptions.populate).length, 2);
       assert.deepEqual(q._mongooseOptions.populate['yellow.brick'], {
@@ -888,7 +888,7 @@ describe('Query', function() {
 
   describe('casting', function() {
     it('to an array of mixed', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       const Product = db.model('Product', productSchema);
       const params = {_id: new DocumentObjectId, tags: {$in: [4, 8, 15, 16]}};
       query.cast(Product, params);
@@ -936,7 +936,7 @@ describe('Query', function() {
     });
 
     it('find $ne should not cast single value to array for schematype of Array', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       const Product = db.model('Product', productSchema);
       const Comment = db.model('Comment', commentSchema);
 
@@ -980,7 +980,7 @@ describe('Query', function() {
     });
 
     it('subdocument array with $ne: null should not throw', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       const Product = db.model('Product', productSchema);
 
       const params = {
@@ -993,7 +993,7 @@ describe('Query', function() {
     });
 
     it('find should not cast single value to array for schematype of Array', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       const Product = db.model('Product', productSchema);
       const Comment = db.model('Comment', commentSchema);
 
@@ -1037,7 +1037,7 @@ describe('Query', function() {
     });
 
     it('an $elemMatch with $in works (gh-1100)', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       const Product = db.model('Product', productSchema);
       const ids = [String(new DocumentObjectId), String(new DocumentObjectId)];
       const params = {ids: {$elemMatch: {$in: ids}}};
@@ -1050,7 +1050,7 @@ describe('Query', function() {
     });
 
     it('inequality operators for an array', function(done) {
-      const query = new Query({}, {}, null);
+      const query = new Query({});
       const Product = db.model('Product', productSchema);
       const Comment = db.model('Comment', commentSchema);
 
@@ -1075,13 +1075,14 @@ describe('Query', function() {
   });
 
   describe('distinct', function() {
-    it('op', function(done) {
+    it('op', function() {
       const Product = db.model('Product', productSchema);
       const prod = new Product({});
-      const q = new Query({}, {}, Product, prod.collection).distinct('blah', function() {
-        assert.equal(q.op, 'distinct');
-        done();
-      });
+      const q = new Query({});
+      
+      q.distinct('blah');
+
+      assert.equal(q.op, 'distinct');
     });
   });
 
@@ -1333,7 +1334,7 @@ describe('Query', function() {
   describe('options', function() {
     describe('maxscan', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.maxscan(100);
         assert.equal(query.options.maxScan, 100);
         done();
@@ -1342,15 +1343,15 @@ describe('Query', function() {
 
     describe('slaveOk', function() {
       it('works', function(done) {
-        let query = new Query({}, {}, null);
+        let query = new Query({});
         query.slaveOk();
         assert.equal(query.options.slaveOk, true);
 
-        query = new Query({}, {}, null);
+        query = new Query({});
         query.slaveOk(true);
         assert.equal(query.options.slaveOk, true);
 
-        query = new Query({}, {}, null);
+        query = new Query({});
         query.slaveOk(false);
         assert.equal(query.options.slaveOk, false);
         done();
@@ -1359,21 +1360,21 @@ describe('Query', function() {
 
     describe('tailable', function() {
       it('works', function(done) {
-        let query = new Query({}, {}, null);
+        let query = new Query({});
         query.tailable();
         assert.equal(query.options.tailable, true);
 
-        query = new Query({}, {}, null);
+        query = new Query({});
         query.tailable(true);
         assert.equal(query.options.tailable, true);
 
-        query = new Query({}, {}, null);
+        query = new Query({});
         query.tailable(false);
         assert.equal(query.options.tailable, false);
         done();
       });
       it('supports passing the `await` option', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.tailable({awaitdata: true});
         assert.equal(query.options.tailable, true);
         assert.equal(query.options.awaitdata, true);
@@ -1393,11 +1394,11 @@ describe('Query', function() {
 
     describe('hint', function() {
       it('works', function(done) {
-        const query2 = new Query({}, {}, null);
+        const query2 = new Query({});
         query2.hint({indexAttributeA: 1, indexAttributeB: -1});
         assert.deepEqual(query2.options.hint, {indexAttributeA: 1, indexAttributeB: -1});
 
-        const query3 = new Query({}, {}, null);
+        const query3 = new Query({});
         query3.hint('indexAttributeA_1');
         assert.deepEqual(query3.options.hint, 'indexAttributeA_1');
 
@@ -1407,7 +1408,7 @@ describe('Query', function() {
 
     describe('snapshot', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.snapshot(true);
         assert.equal(query.options.snapshot, true);
         done();
@@ -1416,7 +1417,7 @@ describe('Query', function() {
 
     describe('batchSize', function() {
       it('works', function(done) {
-        const query = new Query({}, {}, null);
+        const query = new Query({});
         query.batchSize(10);
         assert.equal(query.options.batchSize, 10);
         done();
@@ -1428,7 +1429,7 @@ describe('Query', function() {
 
       describe('without tags', function() {
         it('works', function(done) {
-          const query = new Query({}, {}, null);
+          const query = new Query({});
           query.read('primary');
           assert.ok(query.options.readPreference instanceof P);
           assert.ok(query.options.readPreference.isValid());
@@ -1485,7 +1486,7 @@ describe('Query', function() {
 
       describe('with tags', function() {
         it('works', function(done) {
-          const query = new Query({}, {}, null);
+          const query = new Query({});
           const tags = [{dc: 'sf', s: 1}, {dc: 'jp', s: 2}];
 
           query.read('pp', tags);
@@ -2820,7 +2821,7 @@ describe('Query', function() {
 
   describe('setQuery', function() {
     it('replaces existing query with new value (gh-6854)', function() {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       q.where('userName').exists();
       q.setQuery({ a: 1 });
       assert.deepStrictEqual(q._conditions, { a: 1 });
@@ -3144,7 +3145,7 @@ describe('Query', function() {
 
   describe('setUpdate', function() {
     it('replaces existing update doc with new value', function() {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       q.set('testing', '123');
       q.setUpdate({ $set: { newPath: 'newValue' } });
       assert.strictEqual(q._update.$set.testing, undefined);
@@ -3154,21 +3155,21 @@ describe('Query', function() {
 
   describe('get() (gh-7312)', function() {
     it('works with using $set', function() {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       q.updateOne({}, { $set: { name: 'Jean-Luc Picard' } });
 
       assert.equal(q.get('name'), 'Jean-Luc Picard');
     });
 
     it('works with $set syntactic sugar', function() {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       q.updateOne({}, { name: 'Jean-Luc Picard' });
 
       assert.equal(q.get('name'), 'Jean-Luc Picard');
     });
 
     it('works with mixed', function() {
-      const q = new Query({}, {}, null);
+      const q = new Query({});
       q.updateOne({}, { name: 'Jean-Luc Picard', $set: { age: 59 } });
 
       assert.equal(q.get('name'), 'Jean-Luc Picard');

From c0827933ec127bbfcf7683900e14151e2eb79f8f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 17:25:56 -0500
Subject: [PATCH 0372/2348] style: fix lint

---
 test/query.test.js | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index 35117d5b2f1..0c81a154d70 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1076,10 +1076,8 @@ describe('Query', function() {
 
   describe('distinct', function() {
     it('op', function() {
-      const Product = db.model('Product', productSchema);
-      const prod = new Product({});
       const q = new Query({});
-      
+
       q.distinct('blah');
 
       assert.equal(q.op, 'distinct');

From 780146acc7cf8aeeb76c079392aaa857dee6b7ea Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 17:35:54 -0500
Subject: [PATCH 0373/2348] chore: release 5.8.8

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index bcb71cbf548..d1e079fe1fb 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.8.8 / 2020-01-14
+==================
+ * fix(model): allow using `lean` with `insertMany()` #8507 #8234 [ntsekouras](https://github.com/ntsekouras)
+ * fix(document): don't throw parallel validate error when validating subdoc underneath modified nested path #8486
+ * fix: allow `typePojoToMixed` as top-level option #8501 #8500 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(populate+schematypes): make note of `_id` getter for ObjectIds in populate docs #8483
+
 5.8.7 / 2020-01-10
 ==================
  * fix(documentarray): modify ownerDocument when setting doc array to a doc array thats part of another document #8479
diff --git a/package.json b/package.json
index a1b9b220569..e2f80e7a092 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.8-pre",
+  "version": "5.8.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 96af6babbe43c89bc0ea07f63c38a9293c333068 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 17:39:27 -0500
Subject: [PATCH 0374/2348] chore: update opencollective sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 051eefd4fca..52d053afbde 100644
--- a/index.pug
+++ b/index.pug
@@ -277,6 +277,9 @@ html(lang='en')
               <a href="https://synapsesearch.nz/">
                 <img class="sponsor" src="https://images.opencollective.com/synapsesearch/9f0bc41/logo.png" style="height: 100px">
               </a>
+              <a href="https://maaltidskasser.net/">
+                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/maaltidskasser-logo.png" style="height: 90px" alt="Måltidskasser">
+              </a>
             </div>
           </div>
 

From 6c42e00a474d0f606b4697202cd74b4a1b9bc8ec Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Jan 2020 17:42:41 -0500
Subject: [PATCH 0375/2348] chore: update size

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 52d053afbde..3a5f57b2ecd 100644
--- a/index.pug
+++ b/index.pug
@@ -278,7 +278,7 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/synapsesearch/9f0bc41/logo.png" style="height: 100px">
               </a>
               <a href="https://maaltidskasser.net/">
-                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/maaltidskasser-logo.png" style="height: 90px" alt="Måltidskasser">
+                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/maaltidskasser-logo.png" style="height: 100px" alt="Måltidskasser">
               </a>
             </div>
           </div>

From 14165e77aa8e6eb384b66e4cf38a588d5535474c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Jan 2020 12:14:36 -0500
Subject: [PATCH 0376/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 3a5f57b2ecd..ad71ef80767 100644
--- a/index.pug
+++ b/index.pug
@@ -280,6 +280,9 @@ html(lang='en')
               <a href="https://maaltidskasser.net/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/maaltidskasser-logo.png" style="height: 100px" alt="Måltidskasser">
               </a>
+              <a href="https://taxfreesnus.com/">
+                <img class="sponsor" src="https://images.opencollective.com/taxfreesnus-com/ebf869a/logo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 6af9874ab059eb2151cadcf06da39223fa4860cd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Jan 2020 13:11:20 -0500
Subject: [PATCH 0377/2348] test(populate): repro #8499

---
 test/model.populate.test.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 77a50f2ec86..dc529381646 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9002,7 +9002,7 @@ describe('model: populate:', function() {
     });
   });
 
-  it('succeeds with refPath if embedded discriminator has path with same name but no refPath (gh-8452)', function() {
+  it('succeeds with refPath if embedded discriminator has path with same name but no refPath (gh-8452) (gh-8499)', function() {
     const ImageSchema = Schema({ imageName: String });
     const Image = db.model('gh8452_Image', ImageSchema);
 
@@ -9029,14 +9029,16 @@ describe('model: populate:', function() {
     const Example = db.model('gh8452_Example', ExampleSchema);
 
     return co(function*() {
-      const image = yield Image.create({ imageName: 'image' });
+      const images = yield Image.create([{ imageName: 'image' }, { imageName: 'image2' }]);
       const text = yield Text.create({ textName: 'text' });
       yield Example.create({
         test: '02',
         list: [
-          { __t: 'gh8452_ExtendA', data: image._id, objectType: 'gh8452_Image' },
+          { __t: 'gh8452_ExtendA', data: images[0]._id, objectType: 'gh8452_Image' },
           { __t: 'gh8452_ExtendA', data: text._id, objectType: 'gh8452_Text' },
-          { __t: 'gh8452_ExtendB', data: { sourceId: 123 }, objectType: 'ExternalSourceA' }
+          { __t: 'gh8452_ExtendB', data: { sourceId: 123 }, objectType: 'ExternalSourceA' },
+          { __t: 'gh8452_ExtendA', data: images[1]._id, objectType: 'gh8452_Image' },
+          { __t: 'gh8452_ExtendB', data: { sourceId: 456 }, objectType: 'ExternalSourceB' }
         ]
       });
 
@@ -9044,6 +9046,8 @@ describe('model: populate:', function() {
       assert.equal(res.list[0].data.imageName, 'image');
       assert.equal(res.list[1].data.textName, 'text');
       assert.equal(res.list[2].data.sourceId, 123);
+      assert.equal(res.list[3].data.imageName, 'image2');
+      assert.equal(res.list[4].data.sourceId, 456);
     });
   });
 

From b636c08564fc5280117aa915af22b33f4a909633 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Jan 2020 13:12:02 -0500
Subject: [PATCH 0378/2348] fix(populate): skip populating embedded
 discriminator array values that don't have a `refPath`

Fix #8499
---
 lib/helpers/populate/SkipPopulateValue.js       | 10 ++++++++++
 lib/helpers/populate/assignVals.js              |  6 +++++-
 lib/helpers/populate/getModelsMapForPopulate.js |  3 ++-
 lib/model.js                                    |  2 ++
 4 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 lib/helpers/populate/SkipPopulateValue.js

diff --git a/lib/helpers/populate/SkipPopulateValue.js b/lib/helpers/populate/SkipPopulateValue.js
new file mode 100644
index 00000000000..5d46cfdd8ea
--- /dev/null
+++ b/lib/helpers/populate/SkipPopulateValue.js
@@ -0,0 +1,10 @@
+'use strict';
+
+module.exports = function SkipPopulateValue(val) {
+  if (!(this instanceof SkipPopulateValue)) {
+    return new SkipPopulateValue(val);
+  }
+
+  this.val = val;
+  return this;
+};
\ No newline at end of file
diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index a7a98ad349f..9806f84db64 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -1,5 +1,6 @@
 'use strict';
 
+const SkipPopulateValue = require('./SkipPopulateValue');
 const assignRawDocsToIdStructure = require('./assignRawDocsToIdStructure');
 const get = require('../get');
 const getVirtual = require('./getVirtual');
@@ -35,6 +36,9 @@ module.exports = function assignVals(o) {
     if (count) {
       return val;
     }
+    if (val instanceof SkipPopulateValue) {
+      return val.val;
+    }
     if (o.justOne === true && Array.isArray(val)) {
       return valueFilter(val[0], options, populateOptions);
     } else if (o.justOne === false && !Array.isArray(val)) {
@@ -162,7 +166,7 @@ function valueFilter(val, assignmentOpts, populateOptions) {
     const ret = [];
     const numValues = val.length;
     for (let i = 0; i < numValues; ++i) {
-      const subdoc = val[i];
+      let subdoc = val[i];
       if (!isPopulatedObject(subdoc) && (!populateOptions.retainNullValues || subdoc != null)) {
         continue;
       }
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 37491964f8e..7bd6d34d1dd 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const MongooseError = require('../../error/index');
+const SkipPopulateValue = require('./SkipPopulateValue');
 const get = require('../get');
 const getDiscriminatorByValue = require('../discriminator/getDiscriminatorByValue');
 const isPathExcluded = require('../projection/isPathExcluded');
@@ -214,7 +215,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
             const _path = discriminatorSchema.path(remnant);
             if (_path == null || _path.options.refPath == null) {
               const docValue = utils.getValue(localField.substr(cur.length + 1), subdoc);
-              ret = ret.filter(v => v !== docValue);
+              ret = ret.map(v => v === docValue ? SkipPopulateValue(v) : v);
               continue;
             }
             modelNames.push(utils.getValue(pieces.slice(i + 1).join('.'), subdoc));
diff --git a/lib/model.js b/lib/model.js
index 5c335cf11a0..87177db419b 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -18,6 +18,7 @@ const Query = require('./query');
 const RemoveOptions = require('./options/removeOptions');
 const SaveOptions = require('./options/saveOptions');
 const Schema = require('./schema');
+const SkipPopulateValue = require('./helpers/populate/SkipPopulateValue');
 const TimeoutError = require('./error/timeout');
 const ValidationError = require('./error/validation');
 const VersionError = require('./error/version');
@@ -4542,6 +4543,7 @@ function _assign(model, vals, mod, assignmentOpts) {
  */
 
 function _filterInvalidIds(ids, foreignSchemaType, skipInvalidIds) {
+  ids = ids.filter(v => !(v instanceof SkipPopulateValue));
   if (!skipInvalidIds) {
     return ids;
   }

From b5f744ed212e7db25cde944887f45b1aca33db13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Jan 2020 13:14:05 -0500
Subject: [PATCH 0379/2348] style: fix lint

---
 lib/helpers/populate/assignVals.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 9806f84db64..bd93e81afdc 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -166,7 +166,7 @@ function valueFilter(val, assignmentOpts, populateOptions) {
     const ret = [];
     const numValues = val.length;
     for (let i = 0; i < numValues; ++i) {
-      let subdoc = val[i];
+      const subdoc = val[i];
       if (!isPopulatedObject(subdoc) && (!populateOptions.retainNullValues || subdoc != null)) {
         continue;
       }

From b186b9387887e47fc292dfbc50d17ac86b8c3d0d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Jan 2020 17:37:36 -0500
Subject: [PATCH 0380/2348] test(populate): reuse collections where possible
 for `populate()` tests

Re: #8481
---
 test/model.populate.setting.test.js |   32 +-
 test/model.populate.test.js         | 1320 +++++++++++++--------------
 2 files changed, 627 insertions(+), 725 deletions(-)

diff --git a/test/model.populate.setting.test.js b/test/model.populate.setting.test.js
index e5b4c8be7a9..4cc41babcfa 100644
--- a/test/model.populate.setting.test.js
+++ b/test/model.populate.setting.test.js
@@ -17,13 +17,6 @@ const random = utils.random;
 const Schema = mongoose.Schema;
 const DocObjectId = mongoose.Types.ObjectId;
 
-/**
- * Setup.
- */
-
-const posts = 'blogposts_' + random();
-const users = 'users_' + random();
-
 /**
  * Tests.
  */
@@ -49,24 +42,21 @@ describe('model: populate:', function() {
 
     Object.keys(types).forEach(function(id) {
       describe('should not cast to _id of type ' + id, function() {
-        let refuser;
         let db;
         let B, U;
         let u1;
         let b1, b2;
 
         before(function(done) {
-          refuser = 'RefUser-' + id;
-
           const bSchema = new Schema({
             title: String,
-            fans: [{type: id, ref: refuser}],
+            fans: [{type: id, ref: 'User'}],
             adhoc: [{subdoc: id, subarray: [{things: [id]}]}],
-            _creator: {type: id, ref: refuser},
+            _creator: {type: id, ref: 'User'},
             embed: [{
-              other: {type: id, ref: refuser},
-              array: [{type: id, ref: refuser}],
-              nested: [{subdoc: {type: id, ref: refuser}}]
+              other: {type: id, ref: 'User'},
+              array: [{type: id, ref: 'User'}],
+              nested: [{subdoc: {type: id, ref: 'User'}}]
             }]
           });
 
@@ -77,8 +67,8 @@ describe('model: populate:', function() {
           });
 
           db = start();
-          B = db.model('RefBlogPost-' + id, bSchema, posts + random());
-          U = db.model(refuser, uSchema, users + random());
+          B = db.model('BlogPost', bSchema);
+          U = db.model('User', uSchema);
 
           U.create({
             _id: construct[id](),
@@ -128,8 +118,8 @@ describe('model: populate:', function() {
         it('if a document', function(done) {
           const query = B.findById(b1).
             populate('fans _creator embed.other embed.array embed.nested.subdoc').
-            populate({path: 'adhoc.subdoc', model: refuser}).
-            populate({path: 'adhoc.subarray.things', model: refuser});
+            populate({path: 'adhoc.subdoc', model: 'User'}).
+            populate({path: 'adhoc.subarray.things', model: 'User'});
           query.exec(function(err, doc) {
             assert.ifError(err);
 
@@ -229,8 +219,8 @@ describe('model: populate:', function() {
         it('if an object', function(done) {
           B.findById(b2)
             .populate('fans _creator embed.other embed.array embed.nested.subdoc')
-            .populate({path: 'adhoc.subdoc', model: refuser})
-            .populate({path: 'adhoc.subarray.things', model: refuser})
+            .populate({path: 'adhoc.subdoc', model: 'User'})
+            .populate({path: 'adhoc.subarray.things', model: 'User'})
             .exec(function(err, doc) {
               assert.ifError(err);
 
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index dc529381646..4372377795e 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -12,7 +12,6 @@ const utils = require('../lib/utils');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
-const random = utils.random;
 const Schema = mongoose.Schema;
 const ObjectId = Schema.ObjectId;
 const DocObjectId = mongoose.Types.ObjectId;
@@ -22,32 +21,30 @@ const DocObjectId = mongoose.Types.ObjectId;
  */
 
 describe('model: populate:', function() {
-  this.timeout(process.env.TRAVIS ? 8000 : 4500);
+  this.timeout(8000);
 
-  let User;
-  let Comment;
-  let BlogPost;
-  let posts;
-  let users;
+  let userSchema;
+  let commentSchema;
+  let blogPostSchema;
   let db;
 
   before(function() {
-    User = new Schema({
+    userSchema = new Schema({
       name: String,
       email: String,
       gender: {type: String, enum: ['male', 'female'], default: 'male'},
       age: {type: Number, default: 21},
-      blogposts: [{type: ObjectId, ref: 'RefBlogPost'}],
-      followers: [{type: ObjectId, ref: 'RefUser'}]
+      blogposts: [{type: ObjectId, ref: 'BlogPost'}],
+      followers: [{type: ObjectId, ref: 'User'}]
     });
 
     /**
      * Comment subdocument schema.
      */
 
-    Comment = new Schema({
-      asers: [{type: ObjectId, ref: 'RefUser'}],
-      _creator: {type: ObjectId, ref: 'RefUser'},
+    commentSchema = new Schema({
+      asers: [{type: ObjectId, ref: 'User'}],
+      _creator: {type: ObjectId, ref: 'User'},
       content: String
     });
 
@@ -55,19 +52,13 @@ describe('model: populate:', function() {
      * Blog post schema.
      */
 
-    BlogPost = new Schema({
-      _creator: {type: ObjectId, ref: 'RefUser'},
+    blogPostSchema = new Schema({
+      _creator: {type: ObjectId, ref: 'User'},
       title: String,
-      comments: [Comment],
-      fans: [{type: ObjectId, ref: 'RefUser'}]
+      comments: [commentSchema],
+      fans: [{type: ObjectId, ref: 'User'}]
     });
 
-    posts = 'blogposts_' + random();
-    users = 'users_' + random();
-
-    mongoose.model('RefBlogPost', BlogPost);
-    mongoose.model('RefUser', User);
-    mongoose.model('RefAlternateUser', User);
     db = start();
   });
 
@@ -91,8 +82,8 @@ describe('model: populate:', function() {
   });
 
   it('populating array of object', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({name: 'User 1'}, function(err, user1) {
       assert.ifError(err);
@@ -121,8 +112,8 @@ describe('model: populate:', function() {
   });
 
   it('deep population (gh-3103)', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({name: 'User 01'}, function(err, user1) {
       assert.ifError(err);
@@ -145,7 +136,7 @@ describe('model: populate:', function() {
                 .select('_creator')
                 .populate({
                   path: '_creator',
-                  model: 'RefUser',
+                  model: 'User',
                   select: 'name followers',
                   populate: [{
                     path: 'followers',
@@ -178,16 +169,6 @@ describe('model: populate:', function() {
   });
 
   describe('deep populate', function() {
-    let db;
-
-    before(function() {
-      db = start();
-    });
-
-    after(function(done) {
-      db.close(done);
-    });
-
     it('deep population with refs (gh-3507)', function(done) {
       // handler schema
       const handlerSchema = new Schema({
@@ -197,18 +178,18 @@ describe('model: populate:', function() {
       // task schema
       const taskSchema = new Schema({
         name: String,
-        handler: {type: Schema.Types.ObjectId, ref: 'gh3507_0'}
+        handler: {type: Schema.Types.ObjectId, ref: 'Test'}
       });
 
       // application schema
       const applicationSchema = new Schema({
         name: String,
-        tasks: [{type: Schema.Types.ObjectId, ref: 'gh3507_1'}]
+        tasks: [{type: Schema.Types.ObjectId, ref: 'Test1'}]
       });
 
-      const Handler = db.model('gh3507_0', handlerSchema);
-      const Task = db.model('gh3507_1', taskSchema);
-      const Application = db.model('gh3507_2', applicationSchema);
+      const Handler = db.model('Test', handlerSchema);
+      const Task = db.model('Test1', taskSchema);
+      const Application = db.model('Test2', applicationSchema);
 
       Handler.create({name: 'test'}, function(error, doc) {
         assert.ifError(error);
@@ -303,9 +284,8 @@ describe('model: populate:', function() {
   });
 
   it('populating a single ref', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Guillermo',
@@ -328,14 +308,15 @@ describe('model: populate:', function() {
             assert.ok(post._creator instanceof User);
             assert.equal(post._creator.name, 'Guillermo');
             assert.equal(post._creator.email, 'rauchg@gmail.com');
-            db.close(done);
+            done();
           });
       });
     });
   });
 
   it('not failing on null as ref', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    db.model('User', userSchema);
 
     BlogPost.create({
       title: 'woot',
@@ -356,7 +337,7 @@ describe('model: populate:', function() {
   });
 
   it('not failing on empty object as ref', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
 
     BlogPost.create(
       {title: 'woot'},
@@ -374,8 +355,8 @@ describe('model: populate:', function() {
   it('across DBs', function(done) {
     const db = start();
     const db2 = db.useDb('mongoose_test2');
-    const BlogPost = db.model('RefBlogPost', posts + '2');
-    const User = db2.model('RefUser', users + '2');
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db2.model('User', userSchema);
 
     User.create({
       name: 'Guillermo',
@@ -405,8 +386,8 @@ describe('model: populate:', function() {
   });
 
   it('an error in single ref population propagates', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts + '1');
-    const User = db.model('RefUser', users + '1');
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Guillermo',
@@ -446,9 +427,8 @@ describe('model: populate:', function() {
   });
 
   it('populating with partial fields selection', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Guillermo',
@@ -466,7 +446,6 @@ describe('model: populate:', function() {
           .findById(post._id)
           .populate('_creator', 'email')
           .exec(function(err, post) {
-            db.close();
             assert.ifError(err);
 
             assert.ok(post._creator instanceof User);
@@ -479,9 +458,8 @@ describe('model: populate:', function() {
   });
 
   it('population of single oid with partial field selection and filter', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', 'blogposts_' + random());
-    const User = db.model('RefUser', 'users_' + random());
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Banana',
@@ -506,7 +484,6 @@ describe('model: populate:', function() {
               .findById(post._id)
               .populate('_creator', 'email', {name: 'Banana'})
               .exec(function(err, post) {
-                db.close();
                 assert.ifError(err);
                 assert.ok(post._creator instanceof User);
                 assert.equal(false, post._creator.isInit('name'));
@@ -519,9 +496,8 @@ describe('model: populate:', function() {
   });
 
   it('population of undefined fields in a collection of docs', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', 'blogposts_' + random());
-    const User = db.model('RefUser', 'users_' + random());
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
     User.create({
       name: 'Eloy',
       email: 'eloytoro@gmail.com'
@@ -542,7 +518,6 @@ describe('model: populate:', function() {
             .find()
             .populate('_creator')
             .exec(function(err, posts) {
-              db.close();
               posts.forEach(function(post) {
                 if ('_creator' in post) {
                   assert.ok(post._creator !== null);
@@ -570,9 +545,9 @@ describe('model: populate:', function() {
       items: [userSchema]
     });
 
-    const Company = db.model('gh3859_0', companySchema);
-    const User = db.model('gh3859_1', userSchema);
-    const Sample = db.model('gh3859_2', sampleSchema);
+    const Company = db.model('Company', companySchema);
+    const User = db.model('User', userSchema);
+    const Sample = db.model('Test', sampleSchema);
 
     const company = new Company({name: 'Reynholm Industrie'});
     const user1 = new User({name: 'Douglas', company: company._id});
@@ -606,9 +581,8 @@ describe('model: populate:', function() {
   });
 
   it('population and changing a reference', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Guillermo',
@@ -648,7 +622,6 @@ describe('model: populate:', function() {
                   .findById(post._id)
                   .populate('_creator')
                   .exec(function(err, post) {
-                    db.close();
                     assert.ifError(err);
                     assert.equal(post._creator.name, 'Aaron');
                     assert.equal(post._creator.email, 'aaron.heckmann@gmail.com');
@@ -662,9 +635,8 @@ describe('model: populate:', function() {
   });
 
   it('populating with partial fields selection and changing ref', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Guillermo',
@@ -701,7 +673,6 @@ describe('model: populate:', function() {
                   .findById(post._id)
                   .populate('_creator', '-email')
                   .exec(function(err, post) {
-                    db.close();
                     assert.ifError(err);
 
                     assert.equal(post._creator.name, 'Aaron');
@@ -716,8 +687,8 @@ describe('model: populate:', function() {
   });
 
   it('populating an array of refs and fetching many', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -767,8 +738,8 @@ describe('model: populate:', function() {
   });
 
   it('an error in array reference population propagates', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts + '2');
-    const User = db.model('RefUser', users + '2');
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -821,8 +792,8 @@ describe('model: populate:', function() {
   });
 
   it('populating an array of references with fields selection', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -874,8 +845,8 @@ describe('model: populate:', function() {
   });
 
   it('populating an array of references and filtering', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -958,8 +929,8 @@ describe('model: populate:', function() {
   });
 
   it('populating an array of references and multi-filtering', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -1047,8 +1018,8 @@ describe('model: populate:', function() {
   });
 
   it('populating an array of references and multi-filtering with field selection', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -1113,8 +1084,8 @@ describe('model: populate:', function() {
   });
 
   it('populating an array of refs changing one and removing one', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'Fan 1',
@@ -1192,8 +1163,8 @@ describe('model: populate:', function() {
 
   describe('populating sub docs', function() {
     it('works with findById', function(done) {
-      const BlogPost = db.model('RefBlogPost', posts);
-      const User = db.model('RefUser', users);
+      const BlogPost = db.model('BlogPost', blogPostSchema);
+      const User = db.model('User', userSchema);
 
       User.create({name: 'User 1'}, function(err, user1) {
         assert.ifError(err);
@@ -1229,8 +1200,8 @@ describe('model: populate:', function() {
     });
 
     it('works when first doc returned has empty array for populated path (gh-1055)', function(done) {
-      const BlogPost = db.model('RefBlogPost', posts);
-      const User = db.model('RefUser', users);
+      const BlogPost = db.model('BlogPost', blogPostSchema);
+      const User = db.model('User', userSchema);
 
       User.create({name: 'gh-1055-1'}, {name: 'gh-1055-2'}, function(err, user1, user2) {
         assert.ifError(err);
@@ -1271,8 +1242,8 @@ describe('model: populate:', function() {
   });
 
   it('clears cache when array has been re-assigned (gh-2176)', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts, 'gh-2176-1');
-    const User = db.model('RefUser', users, 'gh-2176-2');
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({name: 'aaron'}, {name: 'val'}, function(err, user1, user2) {
       assert.ifError(err);
@@ -1309,8 +1280,8 @@ describe('model: populate:', function() {
   });
 
   it('populating subdocuments partially', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'User 1',
@@ -1352,8 +1323,8 @@ describe('model: populate:', function() {
   });
 
   it('populating subdocuments partially with conditions', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'User 1',
@@ -1395,8 +1366,8 @@ describe('model: populate:', function() {
   });
 
   it('populating subdocs with invalid/missing subproperties', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({
       name: 'T-100',
@@ -1436,7 +1407,7 @@ describe('model: populate:', function() {
                   // helpful when populating mapReduce results too.
                   BlogPost
                     .findById(post._id)
-                    .populate('comments._idontexist', 'email', 'RefUser')
+                    .populate('comments._idontexist', 'email', 'User')
                     .exec(function(err, post) {
                       assert.ifError(err);
                       assert.ok(post);
@@ -1480,20 +1451,20 @@ describe('model: populate:', function() {
       name: String,
       friends: [{
         type: Schema.ObjectId,
-        ref: 'gh-2151-1'
+        ref: 'User'
       }]
     });
-    const User = db.model('gh-2151-1', user, 'gh-2151-1');
+    const User = db.model('User', user);
 
     const blogpost = new Schema({
       title: String,
       tags: [String],
       author: {
         type: Schema.ObjectId,
-        ref: 'gh-2151-1'
+        ref: 'User'
       }
     });
-    const BlogPost = db.model('gh-2151-2', blogpost, 'gh-2151-2');
+    const BlogPost = db.model('BlogPost', blogpost);
 
     const userIds = [new ObjectId, new ObjectId, new ObjectId, new ObjectId];
     const users = [];
@@ -1568,7 +1539,8 @@ describe('model: populate:', function() {
   });
 
   it('populating subdocuments partially with empty array (gh-481)', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    db.model('User', userSchema);
 
     BlogPost.create({
       title: 'Woot',
@@ -1588,7 +1560,8 @@ describe('model: populate:', function() {
   });
 
   it('populating subdocuments partially with null array', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    db.model('User', userSchema);
 
     BlogPost.create({
       title: 'Woot',
@@ -1608,8 +1581,8 @@ describe('model: populate:', function() {
   });
 
   it('populating subdocuments with array including nulls', function() {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     return co(function*() {
       const user = new User({name: 'hans zimmer'});
@@ -1634,8 +1607,8 @@ describe('model: populate:', function() {
   });
 
   it('supports `retainNullValues` to override filtering out null docs (gh-6432)', function() {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     return co(function*() {
       const user = new User({name: 'Victor Hugo'});
@@ -1664,11 +1637,11 @@ describe('model: populate:', function() {
   });
 
   it('populating more than one array at a time', function(done) {
-    const User = db.model('RefUser', users);
-    const M = db.model('PopMultiSubDocs', new Schema({
-      users: [{type: ObjectId, ref: 'RefUser'}],
-      fans: [{type: ObjectId, ref: 'RefUser'}],
-      comments: [Comment]
+    const User = db.model('User', userSchema);
+    const M = db.model('Test', new Schema({
+      users: [{type: ObjectId, ref: 'User'}],
+      fans: [{type: ObjectId, ref: 'User'}],
+      comments: [commentSchema]
     }));
 
     User.create({
@@ -1737,15 +1710,15 @@ describe('model: populate:', function() {
   });
 
   it('populating multiple children of a sub-array at a time', function(done) {
-    const User = db.model('RefUser', users);
-    const BlogPost = db.model('RefBlogPost', posts);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
     const Inner = new Schema({
-      user: {type: ObjectId, ref: 'RefUser'},
-      post: {type: ObjectId, ref: 'RefBlogPost'}
+      user: {type: ObjectId, ref: 'User'},
+      post: {type: ObjectId, ref: 'BlogPost'}
     });
-    db.model('PopMultiChildrenOfSubDocInner', Inner);
+    db.model('Test1', Inner);
 
-    const M = db.model('PopMultiChildrenOfSubDoc', new Schema({
+    const M = db.model('Test', new Schema({
       kids: [Inner]
     }));
 
@@ -1797,8 +1770,8 @@ describe('model: populate:', function() {
   });
 
   it('passing sort options to the populate method', function(done) {
-    const P = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const P = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create(
       {name: 'aaron', age: 10},
@@ -1858,12 +1831,11 @@ describe('model: populate:', function() {
     const sB = new Schema({
       name: String
     });
-    const name = 'b' + random();
     const sJ = new Schema({
-      b: [{type: Schema.Types.ObjectId, ref: name}]
+      b: [{type: Schema.Types.ObjectId, ref: 'Test'}]
     });
-    const B = db.model(name, sB);
-    const J = db.model('j' + random(), sJ);
+    const B = db.model('Test', sB);
+    const J = db.model('Test1', sJ);
 
     const b1 = new B({name: 'thing1'});
     const b2 = new B({name: 'thing2'});
@@ -1902,7 +1874,8 @@ describe('model: populate:', function() {
   });
 
   it('refs should cast to ObjectId from hexstrings', function(done) {
-    const BP = db.model('RefBlogPost', posts);
+    const BP = db.model('BlogPost', blogPostSchema);
+
     const bp = new BP;
     bp._creator = new DocObjectId().toString();
     assert.ok(bp._creator instanceof DocObjectId);
@@ -1918,12 +1891,12 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: String, ref: 'UserWithStringId'},
+      author: {type: String, ref: 'User'},
       body: String
     });
 
-    const User = db.model('UserWithStringId', UserSchema, random());
-    const Note = db.model('NoteWithStringId', NoteSchema, random());
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({_id: 'alice', name: 'Alice'});
 
@@ -1952,12 +1925,12 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Number, ref: 'UserWithNumberId'},
+      author: {type: Number, ref: 'User'},
       body: String
     });
 
-    const User = db.model('UserWithNumberId', UserSchema, random());
-    const Note = db.model('NoteWithNumberId', NoteSchema, random());
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({_id: 2359, name: 'Alice'});
 
@@ -1983,21 +1956,21 @@ describe('model: populate:', function() {
     const userSchema = new Schema({
       email: {type: String, required: true}
     });
-    const User = db.model('ObjectIdRefRequiredField', userSchema, random());
+    const User = db.model('User', userSchema);
 
     const numSchema = new Schema({_id: Number, val: Number});
-    const Num = db.model('NumberRefRequired', numSchema, random());
+    const Num = db.model('Test', numSchema);
 
     const strSchema = new Schema({_id: String, val: String});
-    const Str = db.model('StringRefRequired', strSchema, random());
+    const Str = db.model('Test1', strSchema);
 
     const commentSchema = new Schema({
-      user: {type: ObjectId, ref: 'ObjectIdRefRequiredField', required: true},
-      num: {type: Number, ref: 'NumberRefRequired', required: true},
-      str: {type: String, ref: 'StringRefRequired', required: true},
+      user: {type: ObjectId, ref: 'User', required: true},
+      num: {type: Number, ref: 'Test', required: true},
+      str: {type: String, ref: 'Test1', required: true},
       text: String
     });
-    const Comment = db.model('CommentWithRequiredField', commentSchema);
+    const Comment = db.model('Comment', commentSchema);
 
     let pending = 3;
 
@@ -2021,7 +1994,7 @@ describe('model: populate:', function() {
 
       comment.save(function(err) {
         assert.ok(err);
-        assert.ok(err.message.indexOf('CommentWithRequiredField validation failed') === 0, err.message);
+        assert.ok(err.message.indexOf('Comment validation failed') === 0, err.message);
         assert.ok('num' in err.errors);
         assert.ok('str' in err.errors);
         assert.ok('user' in err.errors);
@@ -2058,11 +2031,11 @@ describe('model: populate:', function() {
 
   it('populate works with schemas with both id and _id defined', function(done) {
     const S1 = new Schema({id: String});
-    const S2 = new Schema({things: [{type: ObjectId, ref: '_idAndid'}]});
+    const S2 = new Schema({things: [{type: ObjectId, ref: 'Test'}]});
 
-    const M1 = db.model('_idAndid', S1);
-    const M2 = db.model('populateWorksWith_idAndidSchemas', S2);
-    db.model('StringRefRequired', Schema({_id: String, val: String}), random());
+    const M1 = db.model('Test', S1);
+    const M2 = db.model('Test1', S2);
+    db.model('Test2', Schema({_id: String, val: String}));
 
     M1.create(
       {id: 'The Tiger That Isn\'t'}
@@ -2085,8 +2058,8 @@ describe('model: populate:', function() {
   });
 
   it('Update works with populated arrays (gh-602)', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.create({name: 'aphex'}, {name: 'twin'}, function(err, u1, u2) {
       assert.ifError(err);
@@ -2120,9 +2093,8 @@ describe('model: populate:', function() {
   });
 
   it('toJSON should also be called for refs (gh-675)', function(done) {
-    const db = start();
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
 
     User.prototype._toJSON = User.prototype.toJSON;
     User.prototype.toJSON = function() {
@@ -2154,7 +2126,6 @@ describe('model: populate:', function() {
           .findById(post._id)
           .populate('_creator')
           .exec(function(err, post) {
-            db.close();
             assert.ifError(err);
 
             const json = post.toJSON();
@@ -2173,12 +2144,12 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Buffer, ref: 'UserWithBufferId'},
+      author: {type: Buffer, ref: 'User'},
       body: String
     });
 
-    const User = db.model('UserWithBufferId', UserSchema, random());
-    const Note = db.model('NoteWithBufferId', NoteSchema, random());
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({_id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice'});
 
@@ -2207,12 +2178,12 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Buffer, ref: 'UserWithBufferId', required: true},
+      author: {type: Buffer, ref: 'User', required: true},
       body: String
     });
 
-    const User = db.model('UserWithBufferId', UserSchema, random());
-    const Note = db.model('NoteWithBufferId', NoteSchema, random());
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({_id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice'});
 
@@ -2235,8 +2206,8 @@ describe('model: populate:', function() {
   });
 
   it('populating with custom model selection (gh-773)', function(done) {
-    const BlogPost = db.model('RefBlogPost', posts);
-    const User = db.model('RefAlternateUser', users);
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('Test', userSchema);
 
     User.create({
       name: 'Daniel',
@@ -2252,7 +2223,7 @@ describe('model: populate:', function() {
 
         BlogPost
           .findById(post._id)
-          .populate('_creator', 'email', 'RefAlternateUser')
+          .populate('_creator', 'email', 'Test')
           .exec(function(err, post) {
             assert.ifError(err);
 
@@ -2268,9 +2239,8 @@ describe('model: populate:', function() {
 
   describe('specifying a custom model without specifying a ref in schema', function() {
     it('with String _id', function(done) {
-      const db = start();
-      const A = db.model('A', {name: String, _id: String});
-      const B = db.model('B', {other: String});
+      const A = db.model('Test', {name: String, _id: String});
+      const B = db.model('Test1', {other: String});
       A.create({name: 'hello', _id: 'first'}, function(err, a) {
         if (err) {
           return done(err);
@@ -2279,8 +2249,7 @@ describe('model: populate:', function() {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'A'}).exec(function(err, b) {
-            db.close();
+          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2291,9 +2260,8 @@ describe('model: populate:', function() {
       });
     });
     it('with Number _id', function(done) {
-      const db = start();
-      const A = db.model('A', {name: String, _id: Number});
-      const B = db.model('B', {other: Number});
+      const A = db.model('Test', {name: String, _id: Number});
+      const B = db.model('Test1', {other: Number});
       A.create({name: 'hello', _id: 3}, function(err, a) {
         if (err) {
           return done(err);
@@ -2302,8 +2270,7 @@ describe('model: populate:', function() {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'A'}).exec(function(err, b) {
-            db.close();
+          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2314,9 +2281,8 @@ describe('model: populate:', function() {
       });
     });
     it('with Buffer _id', function(done) {
-      const db = start();
-      const A = db.model('A', {name: String, _id: Buffer});
-      const B = db.model('B', {other: Buffer});
+      const A = db.model('Test', {name: String, _id: Buffer});
+      const B = db.model('Test1', {other: Buffer});
       A.create({name: 'hello', _id: Buffer.from('x')}, function(err, a) {
         if (err) {
           return done(err);
@@ -2325,8 +2291,7 @@ describe('model: populate:', function() {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'A'}).exec(function(err, b) {
-            db.close();
+          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2337,9 +2302,8 @@ describe('model: populate:', function() {
       });
     });
     it('with ObjectId _id', function(done) {
-      const db = start();
-      const A = db.model('A', {name: String});
-      const B = db.model('B', {other: Schema.ObjectId});
+      const A = db.model('Test', {name: String});
+      const B = db.model('Test1', {other: Schema.ObjectId});
       A.create({name: 'hello'}, function(err, a) {
         if (err) {
           return done(err);
@@ -2348,8 +2312,7 @@ describe('model: populate:', function() {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'A'}).exec(function(err, b) {
-            db.close();
+          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2362,13 +2325,13 @@ describe('model: populate:', function() {
   });
 
   describe('specifying all params using an object', function() {
-    let db, B, User;
+    let B, User;
     let post;
 
-    before(function() {
-      db = start();
-      B = db.model('RefBlogPost');
-      User = db.model('RefAlternateUser');
+    beforeEach(function() {
+      B = db.model('BlogPost', blogPostSchema);
+      db.deleteModel(/Test/);
+      User = db.model('Test', userSchema);
 
       return User.
         create([
@@ -2383,16 +2346,12 @@ describe('model: populate:', function() {
         then(_post => { post = _post; });
     });
 
-    after(function(done) {
-      db.close(done);
-    });
-
     it('works', function(done) {
       B.findById(post._id)
         .populate({
           path: 'fans',
           select: 'name',
-          model: 'RefAlternateUser',
+          model: 'Test',
           match: {name: /u/},
           options: {sort: {name: -1}}
         })
@@ -2416,13 +2375,12 @@ describe('model: populate:', function() {
   });
 
   describe('Model.populate()', function() {
-    let db, B, User;
+    let B, User;
     let user1, user2, post1, post2, _id;
 
-    before(function(done) {
-      db = start();
-      B = db.model('RefBlogPost', posts);
-      User = db.model('RefAlternateUser', users);
+    beforeEach(function(done) {
+      B = db.model('BlogPost', blogPostSchema);
+      User = db.model('User', userSchema);
 
       _id = new mongoose.Types.ObjectId;
 
@@ -2457,33 +2415,25 @@ describe('model: populate:', function() {
       });
     });
 
-    after(function(done) {
-      db.close(done);
+    it('returns a promise', function(done) {
+      const p = B.populate(post1, '_creator');
+      assert.ok(p instanceof mongoose.Promise);
+      p.then(success, done);
+      function success(doc) {
+        assert.ok(doc);
+        done();
+      }
     });
 
-    describe('returns', function() {
-      it('a promise', function(done) {
-        const p = B.populate(post1, '_creator');
-        assert.ok(p instanceof mongoose.Promise);
-        p.then(success, done);
-        function success(doc) {
-          assert.ok(doc);
+    it('of individual document works', function(done) {
+      B.findById(post1._id, function(error, post1) {
+        const ret = utils.populate({path: '_creator', model: User});
+        B.populate(post1, ret, function(err, post) {
+          assert.ifError(err);
+          assert.ok(post);
+          assert.ok(post._creator instanceof User);
+          assert.equal(post._creator.name, 'Phoenix');
           done();
-        }
-      });
-    });
-
-    describe('of individual document', function() {
-      it('works', function(done) {
-        B.findById(post1._id, function(error, post1) {
-          const ret = utils.populate({path: '_creator', model: 'RefAlternateUser'});
-          B.populate(post1, ret, function(err, post) {
-            assert.ifError(err);
-            assert.ok(post);
-            assert.ok(post._creator instanceof User);
-            assert.equal(post._creator.name, 'Phoenix');
-            done();
-          });
         });
       });
     });
@@ -2491,9 +2441,12 @@ describe('model: populate:', function() {
     describe('a document already populated', function() {
       describe('when paths are not modified', function() {
         it('works', function(done) {
+          db.deleteModel(/User/);
+          const User = db.model('User', userSchema);
+
           B.findById(post1._id, function(err, doc) {
             assert.ifError(err);
-            B.populate(doc, [{path: '_creator', model: 'RefAlternateUser'}, {path: 'fans', model: 'RefAlternateUser'}], function(err, post) {
+            B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
               assert.ifError(err);
               assert.ok(post);
               assert.ok(post._creator instanceof User);
@@ -2505,7 +2458,7 @@ describe('model: populate:', function() {
               assert.equal(String(post._creator._id), String(post.populated('_creator')));
               assert.ok(Array.isArray(post.populated('fans')));
 
-              B.populate(doc, [{path: '_creator', model: 'RefAlternateUser'}, {path: 'fans', model: 'RefAlternateUser'}], function(err, post) {
+              B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
                 assert.ifError(err);
                 assert.ok(post);
                 assert.ok(post._creator instanceof User);
@@ -2525,9 +2478,12 @@ describe('model: populate:', function() {
       });
       describe('when paths are modified', function() {
         it('works', function(done) {
+          db.deleteModel(/User/);
+          const User = db.model('User', userSchema);
+
           B.findById(post1._id, function(err, doc) {
             assert.ifError(err);
-            B.populate(doc, [{path: '_creator', model: 'RefAlternateUser'}, {path: 'fans', model: 'RefAlternateUser'}], function(err, post) {
+            B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
               assert.ifError(err);
               assert.ok(post);
               assert.ok(post._creator instanceof User);
@@ -2543,7 +2499,7 @@ describe('model: populate:', function() {
               doc.markModified('_creator');
               doc.markModified('fans');
 
-              B.populate(doc, [{path: '_creator', model: 'RefAlternateUser'}, {path: 'fans', model: 'RefAlternateUser'}], function(err, post) {
+              B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
                 assert.ifError(err);
                 assert.ok(post);
                 assert.ok(post._creator instanceof User);
@@ -2569,11 +2525,12 @@ describe('model: populate:', function() {
 
     describe('of multiple documents', function() {
       it('works', function(done) {
+        db.model('User', userSchema);
         B.findById(post1._id, function(error, post1) {
           assert.ifError(error);
           B.findById(post2._id, function(error, post2) {
             assert.ifError(error);
-            const ret = utils.populate({path: '_creator', model: 'RefAlternateUser'});
+            const ret = utils.populate({path: '_creator', model: 'User'});
             B.populate([post1, post2], ret, function(err, posts) {
               assert.ifError(err);
               assert.ok(posts);
@@ -2594,9 +2551,8 @@ describe('model: populate:', function() {
 
   describe('populating combined with lean (gh-1260)', function() {
     it('with findOne', function(done) {
-      const db = start();
-      const BlogPost = db.model('RefBlogPost', posts + random());
-      const User = db.model('RefUser', users + random());
+      const BlogPost = db.model('BlogPost', blogPostSchema);
+      const User = db.model('User', userSchema);
 
       User.create({
         name: 'Guillermo',
@@ -2615,7 +2571,6 @@ describe('model: populate:', function() {
             .lean()
             .populate('_creator')
             .exec(function(err, post) {
-              db.close();
               assert.ifError(err);
 
               assert.ok(utils.isObject(post._creator));
@@ -2629,9 +2584,8 @@ describe('model: populate:', function() {
     });
 
     it('with find', function(done) {
-      const db = start();
-      const BlogPost = db.model('RefBlogPost', posts + random());
-      const User = db.model('RefUser', users + random());
+      const BlogPost = db.model('BlogPost', blogPostSchema);
+      const User = db.model('User', userSchema);
 
       User.create({
         name: 'Fan 1',
@@ -2671,7 +2625,7 @@ describe('model: populate:', function() {
               assert.equal(blogposts[1].fans[1].name, 'Fan 1');
               assert.equal(blogposts[1].fans[1].email, 'fan1@learnboost.com');
               assert.equal(typeof blogposts[1].fans[1].update, 'undefined');
-              db.close(done);
+              done();
             });
         });
       });
@@ -2679,16 +2633,14 @@ describe('model: populate:', function() {
   });
 
   describe('records paths and _ids used in population', function() {
-    let db;
     let B;
     let U;
     let u1, u2;
     let b1;
 
-    before(function(done) {
-      db = start();
-      B = db.model('RefBlogPost', posts + random());
-      U = db.model('RefUser', users + random());
+    beforeEach(function(done) {
+      B = db.model('BlogPost', blogPostSchema);
+      U = db.model('User', userSchema);
 
       U.create({
         name: 'Fan 1',
@@ -2717,10 +2669,6 @@ describe('model: populate:', function() {
       });
     });
 
-    after(function() {
-      db.close();
-    });
-
     it('with findOne', function(done) {
       B.findById(b1).populate('fans _creator').exec(function(err, doc) {
         assert.ifError(err);
@@ -2759,19 +2707,18 @@ describe('model: populate:', function() {
   });
 
   describe('deselecting _id', function() {
-    let db, C, U, c1, c2;
-    before(function(done) {
-      db = start();
-
+    let C, U, c1, c2;
+    beforeEach(function(done) {
       C = db.model('Comment', Schema({
         body: 'string', title: String
-      }), 'comments_' + random());
+      }));
 
+      db.deleteModel(/User/);
       U = db.model('User', Schema({
         name: 'string',
         comments: [{type: Schema.ObjectId, ref: 'Comment'}],
         comment: {type: Schema.ObjectId, ref: 'Comment'}
-      }), 'users_' + random());
+      }));
 
       C.create({body: 'comment 1', title: '1'}, {body: 'comment 2', title: 2}, function(err, c1_, c2_) {
         assert.ifError(err);
@@ -2788,10 +2735,6 @@ describe('model: populate:', function() {
       });
     });
 
-    after(function(done) {
-      db.close(done);
-    });
-
     describe('in a subdocument', function() {
       it('works', function(done) {
         U.find({name: 'u1'}).populate('comments', {_id: 0}).exec(function(err, docs) {
@@ -2883,13 +2826,11 @@ describe('model: populate:', function() {
   });
 
   describe('DynRef', function() {
-    let db;
     let Review;
     let Item1;
     let Item2;
 
-    before(function(done) {
-      db = start();
+    beforeEach(function() {
       const reviewSchema = new Schema({
         _id: Number,
         text: String,
@@ -2925,37 +2866,25 @@ describe('model: populate:', function() {
         otherName: String
       });
 
-      Review = db.model('dynrefReview', reviewSchema, 'dynref-0');
-      Item1 = db.model('dynrefItem1', item1Schema, 'dynref-1');
-      Item2 = db.model('dynrefItem2', item2Schema, 'dynref-2');
+      Review = db.model('Review', reviewSchema);
+      Item1 = db.model('Test1', item1Schema);
+      Item2 = db.model('Test2', item2Schema);
 
       const review = {
         _id: 0,
         text: 'Test',
-        item: {id: 1, type: 'dynrefItem1'},
-        items: [{id: 1, type: 'dynrefItem1'}, {id: 2, type: 'dynrefItem2'}]
+        item: {id: 1, type: 'Test1'},
+        items: [{id: 1, type: 'Test1'}, {id: 2, type: 'Test2'}]
       };
 
-      Item1.create({_id: 1, name: 'Val'}, function(err) {
-        if (err) {
-          return done(err);
-        }
-        Item2.create({_id: 2, otherName: 'Val'}, function(err) {
-          if (err) {
-            return done(err);
-          }
-          Review.create(review, function(err) {
-            if (err) {
-              return done(err);
-            }
-            done();
-          });
-        });
-      });
-    });
+      return co(function*() {
+        yield Item1.deleteMany({});
+        yield Item2.deleteMany({});
 
-    after(function(done) {
-      db.close(done);
+        yield Item1.create({_id: 1, name: 'Val'});
+        yield Item2.create({_id: 2, otherName: 'Val'});
+        yield Review.create(review);
+      });
     });
 
     it('Simple populate', function(done) {
@@ -2981,10 +2910,11 @@ describe('model: populate:', function() {
     });
 
     it('with nonexistant refPath (gh-4637)', function(done) {
+      db.deleteModel(/Test/);
       const baseballSchema = mongoose.Schema({
         seam: String
       });
-      const Baseball = db.model('Baseball', baseballSchema);
+      const Baseball = db.model('Test', baseballSchema);
 
       const ballSchema = mongoose.Schema({
         league: String,
@@ -2998,7 +2928,7 @@ describe('model: populate:', function() {
       const basketSchema = mongoose.Schema({
         balls: [ballSchema]
       });
-      const Basket = db.model('Basket', basketSchema);
+      const Basket = db.model('Test2', basketSchema);
 
       new Baseball({seam: 'yarn'}).
         save().
@@ -3007,7 +2937,7 @@ describe('model: populate:', function() {
             balls: [
               {
                 league: 'MLB',
-                kind: 'Baseball',
+                kind: 'Test',
                 ball: baseball._id
               },
               {
@@ -3029,22 +2959,23 @@ describe('model: populate:', function() {
     });
 
     it('array with empty refPath (gh-5377)', function(done) {
+      db.deleteModel(/Test/);
       const modelASchema = new mongoose.Schema({
         name: String
       });
-      const ModelA = db.model('gh5377_a', modelASchema);
+      const ModelA = db.model('Test1', modelASchema);
 
       const modelBSchema = new mongoose.Schema({
         name: String
       });
-      const ModelB = db.model('gh5377_b', modelBSchema);
+      const ModelB = db.model('Test2', modelBSchema);
 
       const ChildSchema = new mongoose.Schema({
         name: String,
         toy: {
           kind: {
             type: String,
-            enum: ['gh5377_a', 'gh5377_b']
+            enum: ['Test1', 'Test2']
           },
           value: {
             type: ObjectId,
@@ -3056,7 +2987,7 @@ describe('model: populate:', function() {
       const ParentSchema = new mongoose.Schema({
         children: [ChildSchema]
       });
-      const Parent = db.model('gh5377', ParentSchema);
+      const Parent = db.model('Test', ParentSchema);
 
       ModelA.create({ name: 'model-A' }, function(error, toyA) {
         assert.ifError(error);
@@ -3066,14 +2997,14 @@ describe('model: populate:', function() {
             children: [
               {
                 name: 'Child 1',
-                toy: { kind: 'gh5377_a', value: toyA._id }
+                toy: { kind: 'Test1', value: toyA._id }
               },
               {
                 name: 'Child 2'
               },
               {
                 name: 'Child 3',
-                toy: { kind: 'gh5377_b', value: toyB._id }
+                toy: { kind: 'Test2', value: toyB._id }
               }
             ]
           }, function(error, doc) {
@@ -3113,8 +3044,8 @@ describe('model: populate:', function() {
         }
       });
 
-      const Locations = db.model('gh5114', LocationSchema);
-      const Users = db.model('gh5114_0', UserSchema);
+      const Locations = db.model('Test', LocationSchema);
+      const Users = db.model('User', UserSchema);
 
       const location1Id = new mongoose.Types.ObjectId();
       const location2Id = new mongoose.Types.ObjectId();
@@ -3128,7 +3059,7 @@ describe('model: populate:', function() {
         name: 'loc2'
       };
       const user = {
-        locationRef: 'gh5114',
+        locationRef: 'Test',
         locationIds: [
           { location: location1Id },
           { location: location2Id }
@@ -3177,9 +3108,9 @@ describe('model: populate:', function() {
         ]
       });
 
-      const StudyPlan = db.model('gh6870_StudyPlan', StudyPlanSchema);
-      const Test = db.model('gh6870_Test', TestSchema);
-      const Lesson = db.model('gh6870_Lesson', LessonSchema);
+      const StudyPlan = db.model('StudyPlan', StudyPlanSchema);
+      const Test = db.model('Test', TestSchema);
+      const Lesson = db.model('Lesson', LessonSchema);
 
       const test = new Test({ _id: 123, exercises: ['t1', 't2'] });
       const lesson = new Lesson({ _id: 'lesson', url: 'https://youtube.com' });
@@ -3190,15 +3121,15 @@ describe('model: populate:', function() {
             contents: [
               {
                 item: test._id,
-                kind: 'gh6870_Test'
+                kind: 'Test'
               },
               {
                 item: lesson._id,
-                kind: 'gh6870_Lesson'
+                kind: 'Lesson'
               },
               {
                 item: lesson._id,
-                kind: 'gh6870_Lesson'
+                kind: 'Lesson'
               }
             ]
           }
@@ -3233,7 +3164,7 @@ describe('model: populate:', function() {
         comments: [CommentSchema]
       });
 
-      const Post = db.model('gh6457', PostSchema);
+      const Post = db.model('Test', PostSchema);
 
       return co(function*() {
         yield Post.create({
@@ -3307,7 +3238,7 @@ describe('model: populate:', function() {
         }
       });
 
-      const Offer = db.model('gh6834', offerSchema);
+      const Offer = db.model('Test', offerSchema);
 
       return co(function*() {
         yield Offer.create({
@@ -3335,7 +3266,7 @@ describe('model: populate:', function() {
     });
 
     coopBrandSchema.virtual('products', {
-      ref: 'gh6435_Product',
+      ref: 'Product',
       localField: '_id',
       foreignField: 'coopBrandId',
       justOne: false
@@ -3351,8 +3282,8 @@ describe('model: populate:', function() {
       name: String
     });
 
-    const Agent = db.model('gh6435_Agent', agentSchema);
-    const Product = db.model('gh6435_Product', productSchema);
+    const Agent = db.model('Test', agentSchema);
+    const Product = db.model('Product', productSchema);
 
     return co(function*() {
       const billy = yield Agent.create({
@@ -3378,19 +3309,14 @@ describe('model: populate:', function() {
   });
 
   describe('leaves Documents within Mixed properties alone (gh-1471)', function() {
-    let db;
     let Cat;
     let Litter;
 
-    before(function() {
-      db = start();
-      Cat = db.model('cats', new Schema({name: String}));
+    beforeEach(function() {
+      db.deleteModel(/Test/);
+      Cat = db.model('Cat', new Schema({name: String}));
       const litterSchema = new Schema({name: String, cats: {}, o: {}, a: []});
-      Litter = db.model('litters', litterSchema);
-    });
-
-    after(function(done) {
-      db.close(done);
+      Litter = db.model('Test', litterSchema);
     });
 
     it('when saving new docs', function(done) {
@@ -3444,22 +3370,12 @@ describe('model: populate:', function() {
   });
 
   describe('github issues', function() {
-    let db;
-
-    before(function() {
-      db = start();
-    });
-
-    after(function(done) {
-      db.close(done);
-    });
-
     it('populating an array of refs, slicing, and fetching many (gh-5737)', function(done) {
-      const BlogPost = db.model('gh5737_0', new Schema({
+      const BlogPost = db.model('BlogPost', new Schema({
         title: String,
-        fans: [{ type: ObjectId, ref: 'gh5737' }]
+        fans: [{ type: ObjectId, ref: 'User' }]
       }));
-      const User = db.model('gh5737', new Schema({ name: String }));
+      const User = db.model('User', new Schema({ name: String }));
 
       User.create([{ name: 'Fan 1' }, { name: 'Fan 2' }], function(error, fans) {
         assert.ifError(error);
@@ -3495,12 +3411,12 @@ describe('model: populate:', function() {
     });
 
     it('populate + slice (gh-5737a)', function(done) {
-      const BlogPost = db.model('gh5737b', new Schema({
+      const BlogPost = db.model('BlogPost', new Schema({
         title: String,
-        user: { type: ObjectId, ref: 'gh5737a' },
+        user: { type: ObjectId, ref: 'User' },
         fans: [{ type: ObjectId}]
       }));
-      const User = db.model('gh5737a', new Schema({ name: String }));
+      const User = db.model('User', new Schema({ name: String }));
 
       User.create([{ name: 'Fan 1' }], function(error, fans) {
         assert.ifError(error);
@@ -3527,15 +3443,15 @@ describe('model: populate:', function() {
     it('maps results back to correct document (gh-1444)', function(done) {
       const articleSchema = new Schema({
         body: String,
-        mediaAttach: {type: Schema.ObjectId, ref: '1444-Media'},
+        mediaAttach: {type: Schema.ObjectId, ref: 'Test'},
         author: String
       });
-      const Article = db.model('1444-Article', articleSchema);
+      const Article = db.model('Article', articleSchema);
 
       const mediaSchema = new Schema({
         filename: String
       });
-      const Media = db.model('1444-Media', mediaSchema);
+      const Media = db.model('Test', mediaSchema);
 
       Media.create({filename: 'one'}, function(err, media) {
         assert.ifError(err);
@@ -3564,10 +3480,10 @@ describe('model: populate:', function() {
 
     it('handles skip', function(done) {
       const movieSchema = new Schema({});
-      const categorySchema = new Schema({movies: [{type: ObjectId, ref: 'gh-2252-1'}]});
+      const categorySchema = new Schema({movies: [{type: ObjectId, ref: 'Movie'}]});
 
-      const Movie = db.model('gh-2252-1', movieSchema);
-      const Category = db.model('gh-2252-2', categorySchema);
+      const Movie = db.model('Movie', movieSchema);
+      const Category = db.model('Category', categorySchema);
 
       Movie.create({}, {}, {}, function(error) {
         assert.ifError(error);
@@ -3588,10 +3504,10 @@ describe('model: populate:', function() {
 
     it('handles slice (gh-1934)', function(done) {
       const movieSchema = new Schema({title: String, actors: [String]});
-      const categorySchema = new Schema({movies: [{type: ObjectId, ref: 'gh-1934-1'}]});
+      const categorySchema = new Schema({movies: [{type: ObjectId, ref: 'Movie'}]});
 
-      const Movie = db.model('gh-1934-1', movieSchema);
-      const Category = db.model('gh-1934-2', categorySchema);
+      const Movie = db.model('Movie', movieSchema);
+      const Category = db.model('Category', categorySchema);
       const movies = [
         {title: 'Rush', actors: ['Chris Hemsworth', 'Daniel Bruhl']},
         {title: 'Pacific Rim', actors: ['Charlie Hunnam', 'Idris Elba']},
@@ -3615,22 +3531,22 @@ describe('model: populate:', function() {
 
     it('fails if sorting with a doc array subprop (gh-2202)', function(done) {
       const childSchema = new Schema({ name: String });
-      const Child = db.model('gh2202', childSchema);
+      const Child = db.model('Child', childSchema);
 
       const parentSchema = new Schema({
         children1: [{
           child: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh2202'
+            ref: 'Child'
           },
           test: Number
         }],
         children2: [{
           type: mongoose.Schema.Types.ObjectId,
-          ref: 'gh2202'
+          ref: 'Child'
         }]
       });
-      const Parent = db.model('gh2202_0', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Child.create([{ name: 'test1' }, { name: 'test2' }], function(error, c) {
         assert.ifError(error);
@@ -3661,7 +3577,7 @@ describe('model: populate:', function() {
     it('handles toObject() (gh-3279)', function(done) {
       const teamSchema = new Schema({
         members: [{
-          user: {type: ObjectId, ref: 'gh3279'},
+          user: {type: ObjectId, ref: 'User'},
           role: String
         }]
       });
@@ -3675,7 +3591,7 @@ describe('model: populate:', function() {
       });
 
 
-      const Team = db.model('gh3279_1', teamSchema);
+      const Team = db.model('Test', teamSchema);
 
       const userSchema = new Schema({
         username: String
@@ -3687,7 +3603,7 @@ describe('model: populate:', function() {
         }
       });
 
-      const User = db.model('gh3279', userSchema);
+      const User = db.model('User', userSchema);
 
       const user = new User({username: 'Test'});
 
@@ -3736,13 +3652,13 @@ describe('model: populate:', function() {
       const activitySchema = new Schema({ title: { type: String } }, options);
 
       const dateActivitySchema = new Schema({
-        postedBy: { type: Schema.Types.ObjectId, ref: 'gh3878', required: true }
+        postedBy: { type: Schema.Types.ObjectId, ref: 'User', required: true }
       }, options);
 
       const eventActivitySchema = new Schema({ test: String }, options);
 
-      const User = db.model('gh3878', { name: String });
-      const Activity = db.model('gh3878_0', activitySchema);
+      const User = db.model('User', { name: String });
+      const Activity = db.model('Test', activitySchema);
       const DateActivity = Activity.discriminator('Date', dateActivitySchema);
       const EventActivity = Activity.discriminator('Event', eventActivitySchema);
 
@@ -3778,11 +3694,11 @@ describe('model: populate:', function() {
       });
       const jobSchema = new Schema({
         title: String,
-        person: { type: Schema.Types.ObjectId, ref: 'gh3992' }
+        person: { type: Schema.Types.ObjectId, ref: 'Person' }
       });
 
-      const Person = db.model('gh3992', personSchema);
-      const Job = db.model('gh3992_0', jobSchema);
+      const Person = db.model('Person', personSchema);
+      const Job = db.model('Job', jobSchema);
 
       Person.create({ name: 'Val' }, function(error, person) {
         assert.ifError(error);
@@ -3806,17 +3722,17 @@ describe('model: populate:', function() {
 
       const teamSchema = new Schema({
         name: { type: String },
-        members: [{ type: Schema.Types.ObjectId, ref: 'gh3904' }]
+        members: [{ type: Schema.Types.ObjectId, ref: 'Person' }]
       });
 
       const gameSchema = new Schema({
-        team: { type: Schema.Types.ObjectId, ref: 'gh3904_0' },
-        opponent: { type: Schema.Types.ObjectId, ref: 'gh3904_0' }
+        team: { type: Schema.Types.ObjectId, ref: 'Team' },
+        opponent: { type: Schema.Types.ObjectId, ref: 'Team' }
       });
 
-      const Person = db.model('gh3904', personSchema);
-      const Team = db.model('gh3904_0', teamSchema);
-      const Game = db.model('gh3904_1', gameSchema);
+      const Person = db.model('Person', personSchema);
+      const Team = db.model('Team', teamSchema);
+      const Game = db.model('Test', gameSchema);
 
       const people = [
         { name: 'Shaq' },
@@ -3872,16 +3788,16 @@ describe('model: populate:', function() {
 
       const teamSchema = new Schema({
         name: { type: String },
-        members: [{ type: Schema.Types.ObjectId, ref: 'gh3954' }]
+        members: [{ type: Schema.Types.ObjectId, ref: 'Person' }]
       });
 
       const gameSchema = new Schema({
-        teams: [{ type: Schema.Types.ObjectId, ref: 'gh3954_0' }]
+        teams: [{ type: Schema.Types.ObjectId, ref: 'Team' }]
       });
 
-      const Person = db.model('gh3954', personSchema);
-      const Team = db.model('gh3954_0', teamSchema);
-      const Game = db.model('gh3954_1', gameSchema);
+      const Person = db.model('Person', personSchema);
+      const Team = db.model('Team', teamSchema);
+      const Game = db.model('Test', gameSchema);
 
       const people = [
         { name: 'Shaq' },
@@ -3942,23 +3858,23 @@ describe('model: populate:', function() {
 
       const level3Schema = new Schema({
         name: { type: String },
-        level4: [{ type: Schema.Types.ObjectId, ref: 'level_4' }]
+        level4: [{ type: Schema.Types.ObjectId, ref: 'Test3' }]
       });
 
       const level2Schema = new Schema({
         name: { type: String },
-        level3: [{ type: Schema.Types.ObjectId, ref: 'level_3' }]
+        level3: [{ type: Schema.Types.ObjectId, ref: 'Test2' }]
       });
 
       const level1Schema = new Schema({
         name: { type: String },
-        level2: [{ type: Schema.Types.ObjectId, ref: 'level_2' }]
+        level2: [{ type: Schema.Types.ObjectId, ref: 'Test1' }]
       });
 
-      const level4 = db.model('level_4', level4Schema);
-      const level3 = db.model('level_3', level3Schema);
-      const level2 = db.model('level_2', level2Schema);
-      const level1 = db.model('level_1', level1Schema);
+      const level4 = db.model('Test3', level4Schema);
+      const level3 = db.model('Test2', level3Schema);
+      const level2 = db.model('Test1', level2Schema);
+      const level1 = db.model('Test', level1Schema);
 
       const l4docs = [{ name: 'level 4' }];
 
@@ -4000,18 +3916,18 @@ describe('model: populate:', function() {
 
       const level2Schema = new Schema({
         name: { type: String },
-        level31: [{ type: Schema.Types.ObjectId, ref: 'gh3974' }],
-        level32: [{ type: Schema.Types.ObjectId, ref: 'gh3974' }]
+        level31: [{ type: Schema.Types.ObjectId, ref: 'Test' }],
+        level32: [{ type: Schema.Types.ObjectId, ref: 'Test' }]
       });
 
       const level1Schema = new Schema({
         name: { type: String },
-        level2: [{ type: Schema.Types.ObjectId, ref: 'gh3974_0' }]
+        level2: [{ type: Schema.Types.ObjectId, ref: 'Test1' }]
       });
 
-      const level3 = db.model('gh3974', level3Schema);
-      const level2 = db.model('gh3974_0', level2Schema);
-      const level1 = db.model('gh3974_1', level1Schema);
+      const level3 = db.model('Test', level3Schema);
+      const level2 = db.model('Test1', level2Schema);
+      const level1 = db.model('Test2', level1Schema);
 
       const l3 = [
         { name: 'level 3/1' },
@@ -4070,26 +3986,26 @@ describe('model: populate:', function() {
       });
 
       const UserEventSchema = new Schema({
-        user: { type: ObjectId, ref: 'gh4073_0' }
+        user: { type: ObjectId, ref: 'User' }
       });
 
       const CommentEventSchema = new Schema({
-        comment: { type: ObjectId, ref: 'gh4073_1' }
+        comment: { type: ObjectId, ref: 'Comment' }
       });
 
       const BlogPostEventSchema = new Schema({
-        blogpost: { type: ObjectId, ref: 'gh4073_2' }
+        blogpost: { type: ObjectId, ref: 'BlogPost' }
       });
 
-      const User = db.model('gh4073_0', UserSchema);
-      const Comment = db.model('gh4073_1', CommentSchema);
-      const BlogPost = db.model('gh4073_2', BlogPostSchema);
+      const User = db.model('User', UserSchema);
+      const Comment = db.model('Comment', CommentSchema);
+      const BlogPost = db.model('BlogPost', BlogPostSchema);
 
-      const Event = db.model('gh4073_3', EventSchema);
-      const UserEvent = Event.discriminator('User4073', UserEventSchema);
-      const CommentEvent = Event.discriminator('Comment4073',
+      const Event = db.model('Test', EventSchema);
+      const UserEvent = Event.discriminator('Test1', UserEventSchema);
+      const CommentEvent = Event.discriminator('Test2',
         CommentEventSchema);
-      const BlogPostEvent = Event.discriminator('BlogPost4073', BlogPostEventSchema);
+      const BlogPostEvent = Event.discriminator('Test3', BlogPostEventSchema);
 
       const u1 = new User({ name: 'user 1' });
       const u2 = new User({ name: 'user 2' });
@@ -4116,11 +4032,11 @@ describe('model: populate:', function() {
         then(() => Event.find({}).populate('user comment blogpost')).
         then(docs => {
           docs.forEach(function(doc) {
-            if (doc.__t === 'User4073') {
+            if (doc.__t === 'Test1') {
               assert.ok(doc.user.name.indexOf('user') !== -1);
-            } else if (doc.__t === 'Comment4073') {
+            } else if (doc.__t === 'Test2') {
               assert.ok(doc.comment.content.indexOf('comment') !== -1);
-            } else if (doc.__t === 'BlogPost4073') {
+            } else if (doc.__t === 'Test3') {
               assert.ok(doc.blogpost.title.indexOf('blog post') !== -1);
             } else {
               assert.ok(false);
@@ -4145,16 +4061,16 @@ describe('model: populate:', function() {
         }
       });
 
-      const Thing = db.model('Thing4104', ThingSchema);
-      const Person = db.model('Person4104', PersonSchema);
-      const Animal = db.model('Animal4104', AnimalSchema);
+      const Thing = db.model('Test1', ThingSchema);
+      const Person = db.model('Person', PersonSchema);
+      const Animal = db.model('Test', AnimalSchema);
 
       Person.create({ name: 'Val' }, function(error, person) {
         assert.ifError(error);
         Animal.create({ name: 'Air Bud' }, function(error, animal) {
           assert.ifError(error);
-          const obj1 = { createdByModel: 'Person4104', createdBy: person._id };
-          const obj2 = { createdByModel: 'Animal4104', createdBy: animal._id };
+          const obj1 = { createdByModel: 'Person', createdBy: person._id };
+          const obj2 = { createdByModel: 'Test', createdBy: animal._id };
           Thing.create(obj1, obj2, function(error) {
             assert.ifError(error);
             Thing.find({}).populate('createdBy').exec(function(error, things) {
@@ -4172,13 +4088,13 @@ describe('model: populate:', function() {
       const demoWrapperSchema = new Schema({
         demo: [{
           type: String,
-          ref: 'gh4656'
+          ref: 'Test'
         }]
       });
       const demoSchema = new Schema({ name: String });
 
-      const Demo = db.model('gh4656', demoSchema);
-      const DemoWrapper = db.model('gh4656_0', demoWrapperSchema);
+      const Demo = db.model('Test', demoSchema);
+      const DemoWrapper = db.model('Test1', demoWrapperSchema);
 
       Demo.create({ name: 'test' }).
         then(function(demo) { return DemoWrapper.create({ demo: [demo._id] }); }).
@@ -4202,8 +4118,8 @@ describe('model: populate:', function() {
         }]
       });
 
-      const Person = db.model('gh4284_b', PersonSchema);
-      const Band = db.model('gh4284_b0', BandSchema);
+      const Person = db.model('Person', PersonSchema);
+      const Band = db.model('Test', BandSchema);
 
       const band = { people: [new mongoose.Types.ObjectId()] };
       Band.create(band, function(error, band) {
@@ -4224,7 +4140,7 @@ describe('model: populate:', function() {
         }]
       });
 
-      const Band = db.model('gh4702', BandSchema);
+      const Band = db.model('Test', BandSchema);
 
       const band = { people: [new mongoose.Types.ObjectId()] };
       Band.create(band, function(error, band) {
@@ -4244,7 +4160,7 @@ describe('model: populate:', function() {
           default: ''
         }
       });
-      db.model('gh4365_0', UserSchema);
+      db.model('User', UserSchema);
 
       const GroupSchema = new mongoose.Schema({
         name: String,
@@ -4254,11 +4170,11 @@ describe('model: populate:', function() {
       const OrganizationSchema = new mongoose.Schema({
         members: [{
           type: mongoose.Schema.Types.ObjectId,
-          ref: 'gh4365_0'
+          ref: 'User'
         }],
         groups: [GroupSchema]
       });
-      const OrganizationModel = db.model('gh4365_1', OrganizationSchema);
+      const OrganizationModel = db.model('Test', OrganizationSchema);
 
       const org = {
         members: [],
@@ -4297,13 +4213,13 @@ describe('model: populate:', function() {
           name: String
         });
         BandSchema.virtual('members', {
-          ref: 'gh2562',
+          ref: 'Person',
           localField: 'name',
           foreignField: 'band'
         });
 
-        const Person = db.model('gh2562', PersonSchema);
-        const Band = db.model('gh2562_0', BandSchema);
+        const Person = db.model('Person', PersonSchema);
+        const Band = db.model('Test', BandSchema);
 
         const people = ['Axl Rose', 'Slash'].map(function(v) {
           return { name: v, band: 'Guns N\' Roses' };
@@ -4326,7 +4242,7 @@ describe('model: populate:', function() {
         const PersonSchema = new Schema({ name: String, band: String });
         const BandSchema = new Schema({ name: String });
         BandSchema.virtual('members', {
-          ref: 'gh6787_Person',
+          ref: 'Person',
           localField: 'name',
           foreignField: 'band',
           options: {
@@ -4334,8 +4250,8 @@ describe('model: populate:', function() {
           }
         });
 
-        const Person = db.model('gh6787_Person', PersonSchema);
-        const Band = db.model('gh6787_Band', BandSchema);
+        const Person = db.model('Person', PersonSchema);
+        const Band = db.model('Test', BandSchema);
 
         const people = ['BB', 'AA', 'AB', 'BA'].map(function(v) {
           return { name: v, band: 'Test' };
@@ -4360,13 +4276,13 @@ describe('model: populate:', function() {
           name: String
         });
         BandSchema.virtual('members', {
-          ref: 'gh2562_a0',
+          ref: 'Person',
           localField: 'name',
           foreignField: 'band'
         });
 
-        const Person = db.model('gh2562_a0', PersonSchema);
-        const Band = db.model('gh2562_a1', BandSchema);
+        const Person = db.model('Person', PersonSchema);
+        const Band = db.model('Test', BandSchema);
 
         let people = ['Axl Rose', 'Slash'].map(function(v) {
           return { name: v, band: 'Guns N\' Roses' };
@@ -4411,7 +4327,7 @@ describe('model: populate:', function() {
         });
         BandSchema.virtual('members');
 
-        const Band = db.model('gh6767_Band', BandSchema);
+        const Band = db.model('Test', BandSchema);
 
         return Band.create({ name: 'Motley Crue' }).
           then(() => Band.find().populate('members')).
@@ -4430,13 +4346,13 @@ describe('model: populate:', function() {
           people: [String]
         });
         BandSchema.virtual('members', {
-          ref: 'gh2562_b0',
+          ref: 'Person',
           localField: 'people',
           foreignField: 'name'
         });
 
-        const Person = db.model('gh2562_b0', PersonSchema);
-        const Band = db.model('gh2562_b1', BandSchema);
+        const Person = db.model('Person', PersonSchema);
+        const Band = db.model('Test', BandSchema);
 
         const bands = [
           { name: 'Guns N\' Roses', people: ['Axl Rose', 'Slash'] },
@@ -4489,18 +4405,18 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('authors', {
-          ref: 'gh4234',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'authored'
         });
         BlogPostSchema.virtual('favoritedBy', {
-          ref: 'gh4234',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'favorites'
         });
 
-        const Person = db.model('gh4234', PersonSchema);
-        const BlogPost = db.model('gh4234_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const blogPosts = [{ _id: 0, title: 'Bacon is Great' }];
         const people = [{ name: 'Val', authored: [0], favorites: [0] }];
@@ -4535,7 +4451,7 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('author', {
-          ref: 'gh4928',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'authored',
           justOne: true
@@ -4545,8 +4461,8 @@ describe('model: populate:', function() {
           blogPosts: [BlogPostSchema]
         });
 
-        const Person = db.model('gh4928', PersonSchema);
-        const Collection = db.model('gh4928_0', CollectionSchema);
+        const Person = db.model('Person', PersonSchema);
+        const Collection = db.model('Test', CollectionSchema);
 
         Person.create({ name: 'Val', authored: 1 }).
           then(function() {
@@ -4575,14 +4491,14 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('author', {
-          ref: 'gh4263',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'authored',
           justOne: true
         });
 
-        const Person = db.model('gh4263', PersonSchema);
-        const BlogPost = db.model('gh4263_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const blogPosts = [{ _id: 0, title: 'Bacon is Great' }];
         const people = [
@@ -4619,14 +4535,14 @@ describe('model: populate:', function() {
           });
 
           BandSchema.virtual('member', {
-            ref: 'gh6234',
+            ref: 'Person',
             localField: 'name',
             foreignField: 'band',
             justOne: true
           });
 
-          const Person = db.model('gh6234', PersonSchema);
-          const Band = db.model('gh6234_0', BandSchema);
+          const Person = db.model('Person', PersonSchema);
+          const Band = db.model('Test', BandSchema);
 
           yield Band.create({ name: 'Guns N\' Roses' });
           yield Band.create({ name: 'Motley Crue' });
@@ -4659,7 +4575,7 @@ describe('model: populate:', function() {
           });
 
           ReportItemSchema.virtual('itemDetail', {
-            ref: 'gh6867_Item',
+            ref: 'Item',
             localField: 'idItem',
             foreignField: '_id',
             justOne: true // here is the problem
@@ -4669,8 +4585,8 @@ describe('model: populate:', function() {
             _id: String
           });
 
-          const ReportModel = db.model('gh6867_Report', ReportSchema);
-          const ItemModel = db.model('gh6867_Item', ItemSchema);
+          const ReportModel = db.model('Test', ReportSchema);
+          const ItemModel = db.model('Item', ItemSchema);
 
           yield ItemModel.create({ _id: 'foo' });
 
@@ -4696,14 +4612,14 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('author', {
-          ref: 'gh4284',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'authored',
           justOne: true
         });
 
-        const Person = db.model('gh4284', PersonSchema);
-        const BlogPost = db.model('gh4284_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const blogPosts = [
           { _id: 0, title: 'Bacon is Great' },
@@ -4733,26 +4649,21 @@ describe('model: populate:', function() {
 
       it('with multiple results and justOne (gh-4329)', function(done) {
         const UserSchema = new Schema({
-          openId: {
-            type: String,
-            unique: true
-          }
+          openId: String
         });
         const TaskSchema = new Schema({
-          openId: {
-            type: String
-          }
+          openId: String
         });
 
         TaskSchema.virtual('user', {
-          ref: 'gh4329',
+          ref: 'User',
           localField: 'openId',
           foreignField: 'openId',
           justOne: true
         });
 
-        const User = db.model('gh4329', UserSchema);
-        const Task = db.model('gh4329_0', TaskSchema);
+        const User = db.model('User', UserSchema);
+        const Task = db.model('Task', TaskSchema);
 
         User.create({ openId: 'user1' }, { openId: 'user2' }, function(error) {
           assert.ifError(error);
@@ -4791,13 +4702,13 @@ describe('model: populate:', function() {
         });
 
         BSchema.virtual('a', {
-          ref: 'gh4618',
+          ref: 'Test',
           localField: 'a_id',
           foreignField: '_id'
         });
 
-        const A = db.model('gh4618', ASchema);
-        const B = db.model('gh4618_0', BSchema);
+        const A = db.model('Test', ASchema);
+        const B = db.model('Test1', BSchema);
 
         A.create({ name: 'test' }).
           then(function(a) {
@@ -4827,14 +4738,14 @@ describe('model: populate:', function() {
         });
 
         BSchema.virtual('a', {
-          ref: 'gh5704',
+          ref: 'Test1',
           localField: function() { return this.localField; },
           foreignField: function() { return '_id'; },
           justOne: true
         });
 
-        const A = db.model('gh5704', ASchema);
-        const B = db.model('gh5704_0', BSchema);
+        const A = db.model('Test1', ASchema);
+        const B = db.model('Test2', BSchema);
 
         A.create([{ name: 'test1' }, { name: 'test2' }]).
           then(function(arr) {
@@ -4881,9 +4792,9 @@ describe('model: populate:', function() {
           justOne: true
         });
 
-        const A1 = db.model('gh5602_1', ASchema);
-        const A2 = db.model('gh5602_2', ASchema);
-        const B = db.model('gh5602_0', BSchema);
+        const A1 = db.model('Test1', ASchema);
+        const A2 = db.model('Test2', ASchema);
+        const B = db.model('Test', BSchema);
 
         A1.create({ name: 'a1' }).
           then(function(a1) {
@@ -4893,8 +4804,8 @@ describe('model: populate:', function() {
           }).
           then(function(as) {
             return B.create([
-              { name: 'test1', referencedModel: 'gh5602_1', aId: as[0]._id },
-              { name: 'test2', referencedModel: 'gh5602_2', aId: as[1]._id }
+              { name: 'test1', referencedModel: 'Test1', aId: as[0]._id },
+              { name: 'test2', referencedModel: 'Test2', aId: as[1]._id }
             ]);
           }).
           then(function() {
@@ -4915,12 +4826,12 @@ describe('model: populate:', function() {
         });
 
         const BSchema = new Schema({
-          as: [{ type: ObjectId, ref: 'gh7397_A' }],
+          as: [{ type: ObjectId, ref: 'Test' }],
           minDate: Date
         });
 
-        const A = db.model('gh7397_A', ASchema);
-        const B = db.model('gh7397_B', BSchema);
+        const A = db.model('Test', ASchema);
+        const B = db.model('Test1', BSchema);
 
         return co(function*() {
           const as = yield A.create([
@@ -4965,14 +4876,14 @@ describe('model: populate:', function() {
         });
 
         BSchema.virtual('as', {
-          ref: 'gh7397_A1',
+          ref: 'Test1',
           localField: '_id',
           foreignField: function() { return this.alternateProperty ? 'b2' : 'b'; },
           options: { match: doc => ({ createdAt: { $gte: doc.minDate } }) }
         });
 
-        const A = db.model('gh7397_A1', ASchema);
-        const B = db.model('gh7397_B1', BSchema);
+        const A = db.model('Test1', ASchema);
+        const B = db.model('Test2', BSchema);
 
         return co(function*() {
           let bs = yield B.create([
@@ -5002,19 +4913,19 @@ describe('model: populate:', function() {
           destination: String
         });
 
-        const Conn = db.model('gh-6669_C', connectionSchema);
+        const Conn = db.model('Test1', connectionSchema);
 
         const userSchema = new Schema({
           name: String
         });
 
-        const User = db.model('gh-6669_U', userSchema);
+        const User = db.model('Test2', userSchema);
 
         const agentSchema = new Schema({
           vendor: String
         });
 
-        const Agent = db.model('gh-6669_A', agentSchema);
+        const Agent = db.model('Test3', agentSchema);
 
         const subSchema = new Schema({
           kind: {
@@ -5035,15 +4946,15 @@ describe('model: populate:', function() {
           agents: [subSchema]
         });
 
-        const Record = db.model('gh-6669_R', recordSchema);
+        const Record = db.model('Test', recordSchema);
 
         const connection = new Conn({ destination: '192.168.1.15' });
         const user = new User({ name: 'Kev' });
         const agent = new Agent({ vendor: 'chrome' });
         const record = new Record({
-          connections: [{ kind: 'gh-6669_C', item: connection._id }],
-          users: [{ kind: 'gh-6669_U', item: user._id }],
-          agents: [{ kind: 'gh-6669_A', item: agent._id }]
+          connections: [{ kind: 'Test1', item: connection._id }],
+          users: [{ kind: 'Test2', item: user._id }],
+          agents: [{ kind: 'Test3', item: agent._id }]
         });
 
         return co(function*() {
@@ -5072,13 +4983,13 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('authors', {
-          ref: 'gh4284_a',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'authored'
         });
 
-        const Person = db.model('gh4284_a', PersonSchema);
-        const BlogPost = db.model('gh4284_a0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const blogPosts = [
           { _id: 0, title: 'Bacon is Great' },
@@ -5121,7 +5032,7 @@ describe('model: populate:', function() {
           title: String
         });
         BlogPostSchema.virtual('authors', {
-          ref: 'Author',
+          ref: 'Person',
           localField: '_id',
           foreignField: 'authored'
         });
@@ -5142,7 +5053,7 @@ describe('model: populate:', function() {
         });
 
         PersonSchema.virtual('blogPosts', {
-          ref: 'gh4261',
+          ref: 'BlogPost',
           localField: '_id',
           foreignField: 'author'
         });
@@ -5150,11 +5061,11 @@ describe('model: populate:', function() {
         const BlogPostSchema = new Schema({
           title: String,
           author: { type: ObjectId },
-          comments: [{ author: { type: ObjectId, ref: 'gh4261' } }]
+          comments: [{ author: { type: ObjectId, ref: 'Person' } }]
         });
 
-        const Person = db.model('gh4261', PersonSchema);
-        const BlogPost = db.model('gh4261_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const people = [
           { name: 'Val' },
@@ -5194,7 +5105,7 @@ describe('model: populate:', function() {
           name: String
         });
         ASchema.virtual('bs', {
-          ref: 'gh4278_1',
+          ref: 'Test2',
           localField: '_id',
           foreignField: 'a'
         });
@@ -5204,7 +5115,7 @@ describe('model: populate:', function() {
           name: String
         });
         BSchema.virtual('cs', {
-          ref: 'gh4278_2',
+          ref: 'Test3',
           localField: '_id',
           foreignField: 'b'
         });
@@ -5214,9 +5125,9 @@ describe('model: populate:', function() {
           name: String
         });
 
-        const A = db.model('gh4278_0', ASchema);
-        const B = db.model('gh4278_1', BSchema);
-        const C = db.model('gh4278_2', CSchema);
+        const A = db.model('Test1', ASchema);
+        const B = db.model('Test2', BSchema);
+        const C = db.model('Test3', CSchema);
 
         A.create({ name: 'A1' }, function(error, a) {
           assert.ifError(error);
@@ -5246,7 +5157,7 @@ describe('model: populate:', function() {
       it('source array (gh-4585)', function(done) {
         const tagSchema = new mongoose.Schema({
           name: String,
-          tagId: { type:String, unique:true }
+          tagId: String
         });
 
         const blogPostSchema = new mongoose.Schema({
@@ -5256,13 +5167,13 @@ describe('model: populate:', function() {
         });
 
         blogPostSchema.virtual('tagsDocuments', {
-          ref: 'gh4585', // model
+          ref: 'Test', // model
           localField: 'tags',
           foreignField: 'tagId'
         });
 
-        const Tag = db.model('gh4585', tagSchema);
-        const BlogPost = db.model('gh4585_0', blogPostSchema);
+        const Tag = db.model('Test', tagSchema);
+        const BlogPost = db.model('BlogPost', blogPostSchema);
 
         const tags = [
           {
@@ -5316,8 +5227,8 @@ describe('model: populate:', function() {
           justOne: false
         });
 
-        const Person = db.model('gh4288', PersonSchema);
-        const BlogPost = db.model('gh4288_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const blogPosts = [
           { _id: 0, title: 'Bacon is Great' }
@@ -5348,34 +5259,34 @@ describe('model: populate:', function() {
         const ClusterSchema = new Schema({
           name: String
         });
-        const Cluster = db.model('gh4923', ClusterSchema);
+        const Cluster = db.model('Test', ClusterSchema);
 
         const ZoneSchema = new Schema({
           name: String,
           clusters: {
             type: [ObjectId],
-            ref: 'gh4923'
+            ref: 'Test'
           }
         });
-        const Zone = db.model('gh4923_1', ZoneSchema);
+        const Zone = db.model('Test1', ZoneSchema);
 
         const DocSchema = new Schema({
           activity: [{
             cluster: {
               type: ObjectId,
-              ref: 'gh4923'
+              ref: 'Test'
             },
             intensity: Number
           }]
         });
         DocSchema.virtual('activity.zones', {
-          ref: 'gh4923_1',
+          ref: 'Test1',
           localField: 'activity.cluster',
           foreignField: 'clusters'
         });
         DocSchema.set('toObject', {virtuals: true});
         DocSchema.set('toJSON', {virtuals: true});
-        const Doc = db.model('gh4923_2', DocSchema);
+        const Doc = db.model('Test2', DocSchema);
 
         Cluster.create([{ name: 'c1' }, { name: 'c2' }, { name: 'c3' }]).
           then(function(c) {
@@ -5430,14 +5341,14 @@ describe('model: populate:', function() {
         });
 
         userSchema.virtual('sessions', {
-          ref: 'gh4741',
+          ref: 'Test',
           localField: '_id',
           foreignField: 'user',
           options: { sort: { date: -1 }, limit: 2 }
         });
 
-        const Session = db.model('gh4741', sessionSchema);
-        const User = db.model('gh4741_0', userSchema);
+        const Session = db.model('Test', sessionSchema);
+        const User = db.model('User', userSchema);
 
         User.create({ name: 'Val' }).
           then(function(user) {
@@ -5466,7 +5377,7 @@ describe('model: populate:', function() {
           name: String
         });
 
-        const User = db.model('gh5036', userSchema);
+        const User = db.model('User', userSchema);
 
         User.findOne().populate().exec(function(error) {
           assert.ifError(error);
@@ -5479,15 +5390,15 @@ describe('model: populate:', function() {
           title: String,
           author: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'Author'
+            ref: 'Person'
           }
         });
         const authorSchema = new Schema({
           name: String
         });
 
-        const Article = db.model('gh6115_Article', articleSchema);
-        const Author = db.model('Author', authorSchema);
+        const Article = db.model('BlogPost', articleSchema);
+        const Author = db.model('Person', authorSchema);
 
         const author = new Author({ name: 'Val' });
         const article = new Article({
@@ -5517,15 +5428,15 @@ describe('model: populate:', function() {
             categories: {
               type: [{
                 type: mongoose.Schema.Types.ObjectId,
-                ref: 'gh5669'
+                ref: 'Test'
               }],
               select: false
             }
           });
 
           const CategorySchema = new Schema({ name: String });
-          const Product = db.model('gh5669_0', ProductSchema);
-          const Category = db.model('gh5669', CategorySchema);
+          const Product = db.model('Product', ProductSchema);
+          const Category = db.model('Test', CategorySchema);
 
           Category.create({ name: 'Books' }, function(error, doc) {
             assert.ifError(error);
@@ -5556,13 +5467,13 @@ describe('model: populate:', function() {
         });
 
         it('disabling at schema level (gh-6546)', function() {
-          const Person = db.model('gh6546_Person', new Schema({ name: String }));
+          const Person = db.model('Person', new Schema({ name: String }));
 
           const bookSchema = new Schema({
             title: 'String',
-            author: { type: 'ObjectId', ref: 'gh6546_Person' }
+            author: { type: 'ObjectId', ref: 'Person' }
           }, { selectPopulatedPaths: false });
-          const Book = db.model('gh6546_Book', bookSchema);
+          const Book = db.model('Product', bookSchema);
 
           return co(function*() {
             const author = yield Person.create({ name: 'Val' });
@@ -5577,13 +5488,13 @@ describe('model: populate:', function() {
         });
 
         it('disabling at global level (gh-6546)', function() {
-          const Person = db.model('gh6546_Person_0', new Schema({ name: String }));
+          const Person = db.model('Person', new Schema({ name: String }));
 
           const bookSchema = new Schema({
             title: 'String',
-            author: { type: 'ObjectId', ref: 'gh6546_Person_0' }
+            author: { type: 'ObjectId', ref: 'Person' }
           });
-          const Book = db.model('gh6546_Book_0', bookSchema);
+          const Book = db.model('Product', bookSchema);
 
           mongoose.set('selectPopulatedPaths', false);
 
@@ -5600,13 +5511,13 @@ describe('model: populate:', function() {
         });
 
         it('schema overwrites global (gh-6546)', function() {
-          const Person = db.model('gh6546_Person_1', new Schema({ name: String }));
+          const Person = db.model('Person', new Schema({ name: String }));
 
           const bookSchema = new Schema({
             title: 'String',
-            author: { type: 'ObjectId', ref: 'gh6546_Person_1' }
+            author: { type: 'ObjectId', ref: 'Person' }
           }, { selectPopulatedPaths: true });
-          const Book = db.model('gh6546_Book_1', bookSchema);
+          const Book = db.model('Product', bookSchema);
 
           mongoose.set('selectPopulatedPaths', false);
 
@@ -5630,7 +5541,7 @@ describe('model: populate:', function() {
             required: true
           }
         });
-        const Image = db.model('gh4817', imagesSchema, 'images');
+        const Image = db.model('Image', imagesSchema);
 
         const fieldSchema = new mongoose.Schema({
           name: {
@@ -5638,16 +5549,16 @@ describe('model: populate:', function() {
             required: true
           }
         });
-        const Field = db.model('gh4817_0', fieldSchema, 'fields');
+        const Field = db.model('Test', fieldSchema, 'fields');
 
         const imageFieldSchema = new mongoose.Schema({
           value: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh4817',
+            ref: 'Image',
             default: null
           }
         });
-        const FieldImage = Field.discriminator('gh4817_1', imageFieldSchema);
+        const FieldImage = Field.discriminator('Test1', imageFieldSchema);
 
         const textFieldSchema = new mongoose.Schema({
           value: {
@@ -5656,7 +5567,7 @@ describe('model: populate:', function() {
             default: {}
           }
         });
-        const FieldText = Field.discriminator('gh4817_2', textFieldSchema);
+        const FieldText = Field.discriminator('Test2', textFieldSchema);
 
         const objectSchema = new mongoose.Schema({
           name: {
@@ -5665,12 +5576,12 @@ describe('model: populate:', function() {
           },
           fields: [{
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh4817_0'
+            ref: 'Test'
           }]
         });
-        const ObjectModel = db.model('gh4817_3', objectSchema, 'objects');
+        const ObjectModel = db.model('Test3', objectSchema);
 
-        Image.create({ name: 'testimg' }).
+        Image.create({ name: 'testing' }).
           then(function(image) {
             return FieldImage.create({ name: 'test', value: image._id });
           }).
@@ -5693,7 +5604,7 @@ describe('model: populate:', function() {
           }).
           then(function(obj) {
             assert.equal(obj.fields.length, 2);
-            assert.equal(obj.fields[0].value.name, 'testimg');
+            assert.equal(obj.fields[0].value.name, 'testing');
             assert.equal(obj.fields[1].value, 'test');
             done();
           }).
@@ -5706,7 +5617,7 @@ describe('model: populate:', function() {
           name: String
         });
 
-        const Person = db.model('gh4843', schema);
+        const Person = db.model('Person', schema);
 
         Person.create({ name: 'Anakin' }).
           then(function(parent) {
@@ -5716,7 +5627,7 @@ describe('model: populate:', function() {
             return Person.findById(luke._id);
           }).
           then(function(luke) {
-            return Person.populate(luke, { path: 'parent', model: 'gh4843' });
+            return Person.populate(luke, { path: 'parent', model: 'Person' });
           }).
           then(function(luke) {
             assert.equal(luke.parent.name, 'Anakin');
@@ -5731,7 +5642,7 @@ describe('model: populate:', function() {
         });
 
         PersonSchema.virtual('blogPosts', {
-          ref: 'gh4631_0',
+          ref: 'BlogPost',
           localField: '_id',
           foreignField: 'author'
         });
@@ -5739,11 +5650,11 @@ describe('model: populate:', function() {
         const BlogPostSchema = new Schema({
           title: String,
           author: { type: ObjectId },
-          comments: [{ author: { type: ObjectId, ref: 'gh4631' } }]
+          comments: [{ author: { type: ObjectId, ref: 'Person' } }]
         });
 
-        const Person = db.model('gh4631', PersonSchema);
-        const BlogPost = db.model('gh4631_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const people = [
           { name: 'Val' },
@@ -5799,7 +5710,7 @@ describe('model: populate:', function() {
             name: String,
             child: {
               type: 'Decimal128',
-              ref: 'gh4759'
+              ref: 'Child'
             }
           });
 
@@ -5808,8 +5719,8 @@ describe('model: populate:', function() {
             name: String
           });
 
-          const Child = db.model('gh4759', childSchema);
-          const Parent = db.model('gh4759_0', parentSchema);
+          const Child = db.model('Child', childSchema);
+          const Parent = db.model('Parent', parentSchema);
 
           const decimal128 = childSchema.path('_id').cast('1.337e+3');
           Child.create({ name: 'Luke', _id: '1.337e+3' }).
@@ -5834,17 +5745,17 @@ describe('model: populate:', function() {
         });
 
         ASchema.virtual('brefs', {
-          ref: 'gh5128_0',
+          ref: 'Test2',
           localField: '_id',
           foreignField: 'arefs'
         });
 
         const BSchema = new Schema({
-          arefs: [{ type: ObjectId, required: true, ref: 'gh5128' }]
+          arefs: [{ type: ObjectId, required: true, ref: 'Test1' }]
         });
 
-        const a = db.model('gh5128', ASchema);
-        const b = db.model('gh5128_0', BSchema);
+        const a = db.model('Test1', ASchema);
+        const b = db.model('Test2', BSchema);
 
         const id1 = new mongoose.Types.ObjectId();
 
@@ -5853,10 +5764,10 @@ describe('model: populate:', function() {
           then(function() {
             return a.findOne({ _id: id1 }).populate([{
               path: 'brefs', // this gets populated
-              model: 'gh5128_0',
+              model: 'Test2',
               populate: [{
-                path: 'arefs', // <---- this is returned as [ObjectId], not populated
-                model: 'gh5128'
+                path: 'arefs',
+                model: 'Test1'
               }]
             }]);
           }).
@@ -5917,7 +5828,7 @@ describe('model: populate:', function() {
           }
         });
         bandSchema.virtual('data.members', {
-          ref: 'gh5431',
+          ref: 'Person',
           localField: 'name',
           foreignField: 'band',
           justOne: false
@@ -5925,8 +5836,8 @@ describe('model: populate:', function() {
 
         bandSchema.set('toObject', { virtuals: true });
 
-        const Person = db.model('gh5431', personSchema);
-        const Band = db.model('gh5431_0', bandSchema);
+        const Person = db.model('Person', personSchema);
+        const Band = db.model('Test', bandSchema);
 
         Band.create({ name: 'Motley Crue', data: {} }).
           then(function() {
@@ -6397,18 +6308,18 @@ describe('model: populate:', function() {
 
         const BookSchema = new mongoose.Schema({
           title: String,
-          author: { type: ObjectId, ref: 'gh5542' }
+          author: { type: ObjectId, ref: 'Person' }
         });
 
         AuthorSchema.virtual('books', {
-          ref: 'gh5542_0',
+          ref: 'Book',
           localField: '_id',
           foreignField: 'author',
           justOne: true
         });
 
-        const Author = db.model('gh5542', AuthorSchema);
-        const Book = db.model('gh5542_0', BookSchema);
+        const Author = db.model('Person', AuthorSchema);
+        const Book = db.model('Book', BookSchema);
 
         const author = new Author({ name: 'Bob' });
         author.save().
@@ -6439,20 +6350,20 @@ describe('model: populate:', function() {
           }
         });
 
-        const Child = db.model('gh5037', childSchema);
+        const Child = db.model('Child', childSchema);
 
         const parentSchema = new mongoose.Schema({
           name: String
         });
 
         parentSchema.virtual('detail', {
-          ref: 'gh5037',
+          ref: 'Child',
           localField: '_id',
           foreignField: 'parent.id',
           justOne: true
         });
 
-        const Parent = db.model('gh5037_0', parentSchema);
+        const Parent = db.model('Parent', parentSchema);
 
         Parent.create({ name: 'Test' }).
           then(function(m) {
@@ -6505,10 +6416,10 @@ describe('model: populate:', function() {
         }, options);
 
         const User = db.model('User', { name: String });
-        const Activity = db.model('gh5858_0', activitySchema);
+        const Activity = db.model('Test1', activitySchema);
         const DateActivity = Activity.discriminator('gh5858_1', dateActivitySchema);
         const EventActivity = Activity.discriminator('gh5858_2', eventActivitySchema);
-        const Log = db.model('gh5858_3', logSchema);
+        const Log = db.model('Test2', logSchema);
 
         let dateActivity;
         let eventActivity;
@@ -6545,7 +6456,7 @@ describe('model: populate:', function() {
       });
 
       it('populating nested discriminator path (gh-5970)', function() {
-        const Author = db.model('gh5970', new mongoose.Schema({
+        const Author = db.model('Person', new mongoose.Schema({
           firstName: {
             type: String,
             required: true
@@ -6566,14 +6477,14 @@ describe('model: populate:', function() {
         const ItemBookSchema = new mongoose.Schema({
           author: {
             type: mongoose.Schema.ObjectId,
-            ref: 'gh5970'
+            ref: 'Person'
           }
         });
 
         const ItemEBookSchema = new mongoose.Schema({
           author: {
             type: mongoose.Schema.ObjectId,
-            ref: 'gh5970'
+            ref: 'Person'
           },
           url: {
             type: String
@@ -6594,7 +6505,7 @@ describe('model: populate:', function() {
         BundleSchema.path('items').discriminator('Book', ItemBookSchema);
         BundleSchema.path('items').discriminator('EBook', ItemEBookSchema);
 
-        const Bundle = db.model('gh5970_0', BundleSchema);
+        const Bundle = db.model('Test', BundleSchema);
 
         return Author.create({firstName: 'David', lastName: 'Flanagan'}).
           then(function(author) {
@@ -6635,8 +6546,8 @@ describe('model: populate:', function() {
           foreignField: 'authored'
         });
 
-        const Person = db.model('gh4264', PersonSchema);
-        const BlogPost = db.model('gh4264_0', BlogPostSchema);
+        const Person = db.model('Person', PersonSchema);
+        const BlogPost = db.model('BlogPost', BlogPostSchema);
 
         const blogPosts = [{ _id: 0, title: 'Bacon is Great' }];
         const people = [
@@ -6665,7 +6576,7 @@ describe('model: populate:', function() {
       return co(function*() {
         // Generate Users Model
         const userSchema = new Schema({ employeeId: Number, name: String });
-        const UserModel = db.model('gh6273', userSchema);
+        const UserModel = db.model('User', userSchema);
 
         // Generate Embedded Discriminators
         const eventSchema = new Schema(
@@ -6690,7 +6601,7 @@ describe('model: populate:', function() {
 
         // Add virtual to first embedded discriminator schema for virtual population
         clickedSchema.virtual('users_$', {
-          ref: 'gh6273',
+          ref: 'User',
           localField: 'users',
           foreignField: 'employeeId'
         });
@@ -6702,7 +6613,7 @@ describe('model: populate:', function() {
           product: { type: String }
         }));
 
-        const Batch = db.model('gh6273_EventBatch', batchSchema);
+        const Batch = db.model('Test', batchSchema);
 
         // Generate Items
         const user = { employeeId: 1, name: 'Test name' };
@@ -6737,15 +6648,15 @@ describe('model: populate:', function() {
             name: String,
             houseId: {
               type: Schema.Types.ObjectId,
-              ref: 'gh6284_0'
+              ref: 'Test'
             },
             cityId: {
               type: Schema.Types.ObjectId,
-              ref: 'gh6284_2'
+              ref: 'Test2'
             },
             districtId: {
               type: Schema.Types.ObjectId,
-              ref: 'gh6284_3'
+              ref: 'Test3'
             }
           });
 
@@ -6753,15 +6664,15 @@ describe('model: populate:', function() {
             content: String,
             userId: {
               type: Schema.Types.ObjectId,
-              ref: 'gh6284_1'
+              ref: 'Test1'
             }
           });
 
-          const House = db.model('gh6284_0', houseSchema);
-          const User = db.model('gh6284_1', userSchema);
-          const City = db.model('gh6284_2', citySchema);
-          const District = db.model('gh6284_3', districtSchema);
-          const Post = db.model('gh6284_4', postSchema);
+          const House = db.model('Test', houseSchema);
+          const User = db.model('Test1', userSchema);
+          const City = db.model('Test2', citySchema);
+          const District = db.model('Test3', districtSchema);
+          const Post = db.model('Post', postSchema);
 
           const house = new House({ location: '123 abc st.' });
           const city = new City({ name: 'Some City' });
@@ -6806,16 +6717,16 @@ describe('model: populate:', function() {
             name: String
           });
 
-          const User = db.model('gh6414User', userSchema);
+          const User = db.model('User', userSchema);
 
           const officeSchema = new Schema({
-            managerId: { type: Schema.ObjectId, ref: 'gh6414User' },
-            supervisorId: { type: Schema.ObjectId, ref: 'gh6414User' },
-            janitorId: { type: Schema.ObjectId, ref: 'gh6414User' },
-            associatesIds: [{ type: Schema.ObjectId, ref: 'gh6414User' }]
+            managerId: { type: Schema.ObjectId, ref: 'User' },
+            supervisorId: { type: Schema.ObjectId, ref: 'User' },
+            janitorId: { type: Schema.ObjectId, ref: 'User' },
+            associatesIds: [{ type: Schema.ObjectId, ref: 'User' }]
           });
 
-          const Office = db.model('gh6414Office', officeSchema);
+          const Office = db.model('Test', officeSchema);
 
           const manager = new User({ name: 'John' });
           const billy = new User({ name: 'Billy' });
@@ -6836,7 +6747,7 @@ describe('model: populate:', function() {
           yield kevin.save();
           yield office.save();
 
-          const doc = yield Office.findOne()
+          const doc = yield Office.findOne({ _id: office._id })
             .populate([
               { path: 'managerId supervisorId associatesIds', select: 'name -_id' },
               { path: 'janitorId', select: 'name -_id' }
@@ -6872,7 +6783,7 @@ describe('model: populate:', function() {
           content: String,
           teacher: {
             type: Schema.Types.ObjectId,
-            ref: 'gh6528_Teacher'
+            ref: 'Test'
           },
           commentIds: [{
             type: Schema.Types.ObjectId
@@ -6888,7 +6799,7 @@ describe('model: populate:', function() {
 
         db.deleteModel(/.*/);
         const User = db.model('User', userSchema);
-        const Teacher = db.model('gh6528_Teacher', teachSchema);
+        const Teacher = db.model('Test', teachSchema);
         const Post = db.model('Post', postSchema);
         const Comment = db.model('Comment', commentSchema);
 
@@ -6965,29 +6876,29 @@ describe('model: populate:', function() {
           name: String,
         });
 
-        const Another = db.model('gh6451another', anotherSchema);
+        const Another = db.model('Test2', anotherSchema);
 
         const otherSchema = new Schema({
           online: Boolean,
           value: String,
           a: {
             type: Schema.Types.ObjectId,
-            ref: 'gh6451another'
+            ref: 'Test2'
           }
         });
 
-        const Other = db.model('gh6451other', otherSchema);
+        const Other = db.model('Test1', otherSchema);
 
         const schema = new Schema({
           visible: Boolean,
           name: String,
           o: [{
             type: Schema.Types.ObjectId,
-            ref: 'gh6451other'
+            ref: 'Test1'
           }]
         });
 
-        const Test = db.model('gh6451test', schema);
+        const Test = db.model('Test', schema);
 
         const another = new Another({
           name: 'testing'
@@ -7035,7 +6946,7 @@ describe('model: populate:', function() {
 
       it('handles embedded discriminator (gh-6487)', function() {
         const userSchema = new Schema({ employeeId: Number, name: String });
-        const UserModel = db.model('gh6487Users', userSchema);
+        const UserModel = db.model('User', userSchema);
 
         const eventSchema = new Schema(
           { message: String },
@@ -7059,7 +6970,7 @@ describe('model: populate:', function() {
         });
 
         clickedSchema.virtual('users_$', {
-          ref: 'gh6487Users',
+          ref: 'User',
           localField: 'users',
           foreignField: 'employeeId'
         });
@@ -7070,7 +6981,7 @@ describe('model: populate:', function() {
           product: { type: String }
         }));
 
-        const Batch = db.model('gh6487EventBatch', batchSchema);
+        const Batch = db.model('Test', batchSchema);
 
         const user = { employeeId: 1, name: 'Test name' };
         const batch = {
@@ -7101,7 +7012,7 @@ describe('model: populate:', function() {
 
         // Generate Product Model
         const productSchema = new Schema({ id: Number, name: String });
-        const Product = db.model('gh6571_Products', productSchema);
+        const Product = db.model('Product', productSchema);
 
         // FlexibleItemSchema discriminator with a bunch of nested subdocs
         const flexibleItemSchema = new Schema();
@@ -7129,14 +7040,14 @@ describe('model: populate:', function() {
         const flexibleProductSchema = new Schema({ products: [{}] });
 
         flexibleProductSchema.virtual('products_$', {
-          ref: 'gh6571_Products',
+          ref: 'Product',
           localField: 'products.id',
           foreignField: 'id'
         });
 
         docArray.discriminator('6571_ProductDisc', flexibleProductSchema);
 
-        const FlexibleItem = db.model('gh6571_FlexibleItem', flexibleItemSchema);
+        const FlexibleItem = db.model('Test', flexibleItemSchema);
 
         // Generate items
         yield User.create({ id: 111, name: 'John Doe' });
@@ -7172,7 +7083,7 @@ describe('model: populate:', function() {
       const commentSchema = new Schema({
         metadata: {
           type: Schema.Types.ObjectId,
-          ref: 'MetaData-6845'
+          ref: 'Test'
         },
       });
 
@@ -7186,8 +7097,8 @@ describe('model: populate:', function() {
         posts: [postSchema]
       });
 
-      db.model('MetaData-6845', metaDataSchema);
-      const User = db.model('User-6845', userSchema);
+      db.model('Test', metaDataSchema);
+      const User = db.model('User', userSchema);
 
       const user = yield User.findOneAndUpdate(
         { username: 'Jennifer' }, /* upsert username but missing posts */
@@ -7209,7 +7120,7 @@ describe('model: populate:', function() {
         company: String
       });
 
-      const Job = db.model('gh6509_job', jobSchema);
+      const Job = db.model('Job', jobSchema);
 
       const volunteerSchema = new Schema({
         kind: String,
@@ -7217,7 +7128,7 @@ describe('model: populate:', function() {
         org: String
       });
 
-      const Volunteer = db.model('gh6509_charity', volunteerSchema);
+      const Volunteer = db.model('Test1', volunteerSchema);
 
       const cvSchema = new Schema({
         title: String,
@@ -7236,16 +7147,16 @@ describe('model: populate:', function() {
         }]
       });
 
-      const CV = db.model('gh6509_cv', cvSchema);
+      const CV = db.model('Test2', cvSchema);
 
       const job = new Job({
-        kind: 'gh6509_job',
+        kind: 'Job',
         title: 'janitor',
         company: 'Bait & Tackle'
       });
 
       const volunteer = new Volunteer({
-        kind: 'gh6509_charity',
+        kind: 'Test1',
         resp: 'construction',
         org: 'Habitat for Humanity'
       });
@@ -7256,8 +7167,8 @@ describe('model: populate:', function() {
           name: 'Experience',
           active: true,
           list: [
-            { kind: 'gh6509_job', active: true, item: job._id },
-            { kind: 'gh6509_charity', active: true, item: volunteer._id }
+            { kind: 'Job', active: true, item: job._id },
+            { kind: 'Test1', active: true, item: volunteer._id }
           ]
         }]
       });
@@ -7288,16 +7199,16 @@ describe('model: populate:', function() {
     beforeEach(function() {
       const userSchema = new Schema({
         name: String,
-        roomId: { type: Schema.ObjectId, ref: 'gh6498_Room' }
+        roomId: { type: Schema.ObjectId, ref: 'Test1' }
       });
       const officeSchema = new Schema();
       const roomSchema = new Schema({
-        officeId: { type: Schema.ObjectId, ref: 'gh6498_Office' }
+        officeId: { type: Schema.ObjectId, ref: 'Test2' }
       });
 
       const User = db.model('User', userSchema);
-      const Office = db.model('gh6498_Office', officeSchema);
-      const Room = db.model('gh6498_Room', roomSchema);
+      const Office = db.model('Test2', officeSchema);
+      const Room = db.model('Test1', roomSchema);
 
       const user = new User();
       const office = new Office();
@@ -7430,7 +7341,7 @@ describe('model: populate:', function() {
     });
 
     docArray.discriminator('Clicked', clickedSchema);
-    const Batch = db.model('gh6554_EventBatch', batchSchema);
+    const Batch = db.model('Test', batchSchema);
 
     const user = { employeeId: 1, name: 'Test name' };
     const batch = {
@@ -7496,7 +7407,7 @@ describe('model: populate:', function() {
     });
 
     docArray.discriminator('Clicked', clickedSchema);
-    const Batch = db.model('gh6612_EventBatch', batchSchema);
+    const Batch = db.model('Test', batchSchema);
 
     const user = { employeeId: 1, name: 'Test name' };
     const author = { employeeId: 2, name: 'Author Name' };
@@ -7547,7 +7458,7 @@ describe('model: populate:', function() {
     });
 
     const User = db.model('User', userSchema);
-    const Test = db.model('gh6618_test', schema);
+    const Test = db.model('Test', schema);
 
     const user = new User({ name: 'billy' });
     const test = new Test({ referrer: 'Model$' + user.name });
@@ -7661,12 +7572,12 @@ describe('model: populate:', function() {
       test: String
     });
 
-    const Role = db.model('gh6714_Role', schema);
+    const Role = db.model('Test', schema);
 
     return co(function*() {
       const role = yield Role.create({ });
       const role2 = yield Role.create({
-        parent: { kind: 'gh6714_Role', item: role._id }
+        parent: { kind: 'Test', item: role._id }
       });
 
       const toUpdate = yield Role.find({ _id: role2._id }).
@@ -7737,7 +7648,7 @@ describe('model: populate:', function() {
       price: 'Number',
       image: {
         type: 'ObjectId',
-        ref: 'gh6798_File'
+        ref: 'Test'
       }
     });
     const EditionSchema = new Schema({ editionOptions: EditionOptionsSchema });
@@ -7747,7 +7658,7 @@ describe('model: populate:', function() {
       },
       editions: [{
         type: 'ObjectId',
-        ref: 'gh6798_Edition'
+        ref: 'Test1'
       }]
     });
     const CarSchema = new mongoose.Schema({
@@ -7755,9 +7666,9 @@ describe('model: populate:', function() {
       versions: [CarVersionSchema]
     });
 
-    const File = db.model('gh6798_File', FileSchema);
-    const Edition = db.model('gh6798_Edition', EditionSchema);
-    const Car = db.model('gh6798_Car', CarSchema);
+    const File = db.model('Test', FileSchema);
+    const Edition = db.model('Test1', EditionSchema);
+    const Car = db.model('Car', CarSchema);
 
     return co(function*() {
       const file = yield File.create({ filename: 'file1.png' });
@@ -7898,8 +7809,8 @@ describe('model: populate:', function() {
       data: Schema.Types.Mixed
     });
 
-    const Article = db.model('gh6985_Article_0', articleSchema);
-    const Test = db.model('gh6985_Test_0', schema);
+    const Article = db.model('Article', articleSchema);
+    const Test = db.model('Test', schema);
 
     return co(function*() {
       const articles = yield Article.create([
@@ -7916,7 +7827,7 @@ describe('model: populate:', function() {
       const popObj = {
         path: 'data.articles',
         select: 'title',
-        model: 'gh6985_Article_0',
+        model: 'Article',
         justOne: true,
         options: { lean: true }
       };
@@ -7939,7 +7850,7 @@ describe('model: populate:', function() {
       sourceOrderId: Number
     });
     RefundSchema.virtual('orders', {
-      ref: 'gh5704_Order',
+      ref: 'Order',
       localField: function() {
         return this.internalOrderId ? 'internalOrderId' : 'sourceOrderId';
       },
@@ -7948,8 +7859,8 @@ describe('model: populate:', function() {
       }
     });
 
-    const Order = db.model('gh5704_Order', OrderSchema);
-    const Refund = db.model('gh5704_Refund', RefundSchema);
+    const Order = db.model('Order', OrderSchema);
+    const Refund = db.model('Test', RefundSchema);
 
     return co(function*() {
       yield Order.create([
@@ -7987,9 +7898,9 @@ describe('model: populate:', function() {
 
     const trickSchema = new Schema({ description: String });
 
-    const Owner = db.model('gh7052_Owner', ownerSchema);
-    const Dog = db.model('gh7052_Dog', dogSchema);
-    const Trick = db.model('gh7052_Trick', trickSchema);
+    const Owner = db.model('Person', ownerSchema);
+    const Dog = db.model('Test', dogSchema);
+    const Trick = db.model('Test1', trickSchema);
 
     const t = new Trick({ description: 'roll over'});
     const d = new Dog({ name: 'Fido', trick: t._id });
@@ -8000,9 +7911,9 @@ describe('model: populate:', function() {
 
       const owner = yield Owner.findOne({}).lean();
       let populated = yield Owner.populate(owner,
-        [{ path: 'dogs', model: 'gh7052_Dog', options: { lean: true } }]);
+        [{ path: 'dogs', model: 'Test', options: { lean: true } }]);
       populated = yield Owner.populate(owner,
-        [{ path: 'dogs.trick', model: 'gh7052_Trick', options: { lean: true } }]);
+        [{ path: 'dogs.trick', model: 'Test1', options: { lean: true } }]);
 
       assert.ok(!Array.isArray(populated.dogs[0].trick));
     });
@@ -8012,12 +7923,12 @@ describe('model: populate:', function() {
     const CatSchema = mongoose.Schema({ name: String }, { toObject: { virtuals: true } });
 
     CatSchema.virtual('friends', {
-      ref: 'gh7050_Dog',
+      ref: 'Test',
       localField: '_id',
       foreignField: 'cat'
     });
 
-    const Cat = db.model('gh7050_Cat', CatSchema);
+    const Cat = db.model('Cat', CatSchema);
 
     const DogSchema = mongoose.Schema({
       name: String,
@@ -8025,7 +7936,7 @@ describe('model: populate:', function() {
       secret: { type: String, select: false }
     });
 
-    const Dog = db.model('gh7050_Dog', DogSchema);
+    const Dog = db.model('Test', DogSchema);
 
     return co(function*() {
       const kitty = yield Cat.create({ name: 'foo' });
@@ -8144,7 +8055,7 @@ describe('model: populate:', function() {
     const s1 = new mongoose.Schema({});
 
     s1.virtual('s2', {
-      ref: 'gh7573_s2',
+      ref: 'Test2',
       localField: '_id',
       foreignField: 's1'
     });
@@ -8154,7 +8065,7 @@ describe('model: populate:', function() {
     });
 
     s2.virtual('numS3', {
-      ref: 'gh7573_s3',
+      ref: 'Test3',
       localField: '_id',
       foreignField: 's2',
       count: true
@@ -8165,9 +8076,9 @@ describe('model: populate:', function() {
     });
 
     return co(function*() {
-      const S1 = db.model('gh7573_s1', s1);
-      const S2 = db.model('gh7573_s2', s2);
-      const S3 = db.model('gh7573_s3', s3);
+      const S1 = db.model('Test1', s1);
+      const S2 = db.model('Test2', s2);
+      const S3 = db.model('Test3', s3);
 
       const s1doc = yield S1.create({});
       const s2docs = yield S2.create([{ s1: s1doc }, { s1: s1doc }]);
@@ -8187,7 +8098,7 @@ describe('model: populate:', function() {
   it('explicit model option overrides refPath (gh-7273)', function() {
     const userSchema = new Schema({ name: String });
     const User1 = db.model('User', userSchema);
-    db.model('User2', userSchema);
+    db.model('Test', userSchema);
 
     const postSchema = new Schema({
       user: {
@@ -8200,7 +8111,7 @@ describe('model: populate:', function() {
 
     return co(function*() {
       const user = yield User1.create({ name: 'val' });
-      yield Post.create({ user: user._id, m: 'User2' });
+      yield Post.create({ user: user._id, m: 'Test' });
 
       let post = yield Post.findOne().populate('user');
       assert.ok(!post.user);
@@ -8256,13 +8167,13 @@ describe('model: populate:', function() {
 
     const artistSchema = new Schema({ _id: Number, name: String });
     artistSchema.virtual('songs', {
-      ref: 'gh7374_Song',
+      ref: 'Test',
       localField: '_id',
       foreignField: 'identifiers.artists.artist'
     });
 
-    const Song = db.model('gh7374_Song', songSchema);
-    const Artist = db.model('gh7374_Artist', artistSchema);
+    const Song = db.model('Test', songSchema);
+    const Artist = db.model('Person', artistSchema);
 
     return co(function*() {
       yield Artist.create([
@@ -8291,11 +8202,11 @@ describe('model: populate:', function() {
       }]
     });
 
-    const Model = db.model('gh7273', schema);
+    const Model = db.model('Test', schema);
 
     const itemSchema = new Schema({ name: String });
-    const Item1 = db.model('gh7273_Item1', itemSchema);
-    const Item2 = db.model('gh7273_Item2', itemSchema);
+    const Item1 = db.model('Test1', itemSchema);
+    const Item2 = db.model('Test2', itemSchema);
 
     return co(function*() {
       const item1 = yield Item1.create({ name: 'item1' });
@@ -8304,8 +8215,8 @@ describe('model: populate:', function() {
       yield Model.create({
         arr1: [{
           arr2: [
-            { item: item1._id, kind: 'gh7273_Item1' },
-            { item: item2._id, kind: 'gh7273_Item2' }
+            { item: item1._id, kind: 'Test1' },
+            { item: item2._id, kind: 'Test2' }
           ]
         }]
       });
@@ -8340,11 +8251,11 @@ describe('model: populate:', function() {
   it('supports populating a path in a document array embedded in an array (gh-7647)', function() {
     const schema = new Schema({
       recordings: [[{
-        file: { type: Schema.ObjectId, ref: 'gh7647_Asset' }
+        file: { type: Schema.ObjectId, ref: 'Test' }
       }]]
     });
-    const Song = db.model('gh7647_Song', schema);
-    const Asset = db.model('gh7647_Asset', Schema({ name: String }));
+    const Song = db.model('Test1', schema);
+    const Asset = db.model('Test', Schema({ name: String }));
 
     return co(function*() {
       const a = yield Asset.create({ name: 'foo' });
@@ -8361,18 +8272,18 @@ describe('model: populate:', function() {
 
   it('handles populating deeply nested path if value in db is a primitive (gh-7545)', function() {
     const personSchema = new Schema({ _id: Number, name: String });
-    const PersonModel = db.model('gh7545_People', personSchema);
+    const PersonModel = db.model('Person', personSchema);
 
     // Create Event Model
     const teamSchema = new Schema({
-      nested: { members: [{ type: Number, ref: 'gh7545_People' }] }
+      nested: { members: [{ type: Number, ref: 'Person' }] }
     });
     const eventSchema = new Schema({
       _id: Number,
       title: String,
       teams: [teamSchema]
     });
-    const EventModel = db.model('gh7545_Event', eventSchema);
+    const EventModel = db.model('Test', eventSchema);
 
     return co(function*() {
       yield PersonModel.create({ _id: 1, name: 'foo' });
@@ -8399,15 +8310,15 @@ describe('model: populate:', function() {
       }]
     });
     GroupSchema.virtual('roles$', {
-      ref: 'gh8230_Role',
+      ref: 'Test',
       localField: 'roles.roleId',
       foreignField: '_id'
     });
 
     const RoleSchema = new Schema({});
 
-    const GroupModel = db.model('gh8230_Group', GroupSchema);
-    db.model('gh8230_Role', RoleSchema);
+    const GroupModel = db.model('Group', GroupSchema);
+    db.model('Test', RoleSchema);
 
     return co(function*() {
       yield GroupModel.create({ roles: [] });
@@ -8424,7 +8335,7 @@ describe('model: populate:', function() {
       }]
     });
     GroupSchema.virtual('rolesCount', {
-      ref: 'gh7731_Role',
+      ref: 'Test',
       localField: 'roles.roleId',
       foreignField: '_id',
       count: true
@@ -8432,8 +8343,8 @@ describe('model: populate:', function() {
 
     const RoleSchema = new Schema({});
 
-    const GroupModel = db.model('gh7731_Group', GroupSchema);
-    db.model('gh7731_Role', RoleSchema);
+    const GroupModel = db.model('Group', GroupSchema);
+    db.model('Test', RoleSchema);
 
     return co(function*() {
       yield GroupModel.create({ roles: [] });
@@ -8510,9 +8421,9 @@ describe('model: populate:', function() {
         ref: doc => doc.kind
       }
     });
-    const Model = db.model('gh7669', schema);
-    const Movie = db.model('gh7669_Movie', new Schema({ name: String }));
-    const Book = db.model('gh7669_Book', new Schema({ title: String }));
+    const Model = db.model('Test', schema);
+    const Movie = db.model('Movie', new Schema({ name: String }));
+    const Book = db.model('Book', new Schema({ title: String }));
 
     return co(function*() {
       const docs = yield [
@@ -8521,15 +8432,15 @@ describe('model: populate:', function() {
       ];
 
       yield Model.create([
-        { kind: 'gh7669_Movie', media: docs[0]._id },
-        { kind: 'gh7669_Book', media: docs[1]._id }
+        { kind: 'Movie', media: docs[0]._id },
+        { kind: 'Book', media: docs[1]._id }
       ]);
 
       const res = yield Model.find().sort({ kind: -1 }).populate('media');
 
-      assert.equal(res[0].kind, 'gh7669_Movie');
+      assert.equal(res[0].kind, 'Movie');
       assert.equal(res[0].media.name, 'The Empire Strikes Back');
-      assert.equal(res[1].kind, 'gh7669_Book');
+      assert.equal(res[1].kind, 'Book');
       assert.equal(res[1].media.title, 'New Jedi Order');
     });
   });
@@ -8566,13 +8477,13 @@ describe('model: populate:', function() {
     const options = { discriminatorKey: 'kind' };
     const Post = db.model('Post', new Schema({ time: Date, text: String }, options));
 
-    const MediaPost = Post.discriminator('gh5109_MediaPost', new Schema({
+    const MediaPost = Post.discriminator('Test', new Schema({
       media: { type: Schema.Types.ObjectId, refPath: 'mediaType' },
       mediaType: String // either 'Image' or 'Video'
     }, options));
-    const Image = db.model('gh5109_Image',
+    const Image = db.model('Image',
       new Schema({ url: String }));
-    const Video = db.model('gh5109_Video',
+    const Video = db.model('Video',
       new Schema({ url: String, duration: Number }));
 
     return co(function*() {
@@ -8580,8 +8491,8 @@ describe('model: populate:', function() {
       const video = yield Video.create({ url: 'foo', duration: 42 });
 
       yield MediaPost.create([
-        { media: image._id, mediaType: 'gh5109_Image' },
-        { media: video._id, mediaType: 'gh5109_Video' }
+        { media: image._id, mediaType: 'Image' },
+        { media: video._id, mediaType: 'Video' }
       ]);
 
       const docs = yield Post.find().populate('media').sort({ mediaType: 1 });
@@ -8606,16 +8517,16 @@ describe('model: populate:', function() {
     postSchema.virtual('mediaType').get(function() { return this._mediaType; });
 
     const Post = db.model('Post', postSchema);
-    const Image = db.model('gh7341_Image', new Schema({ url: String }));
-    const Video = db.model('gh7341_Video', new Schema({ url: String, duration: Number }));
+    const Image = db.model('Image', new Schema({ url: String }));
+    const Video = db.model('Video', new Schema({ url: String, duration: Number }));
 
     return co(function*() {
       const image = yield Image.create({ url: 'test' });
       const video = yield Video.create({ url: 'foo', duration: 42 });
 
       yield Post.create([
-        { media: image._id, _mediaType: 'gh7341_Image' },
-        { media: video._id, _mediaType: 'gh7341_Video' }
+        { media: image._id, _mediaType: 'Image' },
+        { media: video._id, _mediaType: 'Video' }
       ]);
 
       const docs = yield Post.find().populate('media').sort({ _mediaType: 1 });
@@ -8641,14 +8552,14 @@ describe('model: populate:', function() {
     });
 
     DeveloperSchema.virtual('ticketCount', {
-      ref: 'gh7573_Ticket',
+      ref: 'Test',
       localField: 'name',
       foreignField: 'assigned',
       count: true
     });
 
-    const Ticket = db.model('gh7573_Ticket', TicketSchema);
-    const Team = db.model('gh7573_Team', TeamSchema);
+    const Ticket = db.model('Test', TicketSchema);
+    const Team = db.model('Team', TeamSchema);
 
     return co(function*() {
       yield Team.create({
@@ -8689,7 +8600,7 @@ describe('model: populate:', function() {
       docArray.discriminator('Clicked', Schema({ nestedLayer: nestedLayerSchema }));
       docArray.discriminator('Purchased', Schema({ purchased: String }));
 
-      const Batch = db.model('gh6488', batchSchema);
+      const Batch = db.model('Test', batchSchema);
 
       yield UserModel.create({ employeeId: 1, name: 'test' });
       yield Batch.create({
@@ -8716,19 +8627,19 @@ describe('model: populate:', function() {
     const FooSchema = new Schema({
       name: String,
       children: [{
-        barId: { type: Schema.Types.ObjectId, ref: 'gh8198_Bar' },
+        barId: { type: Schema.Types.ObjectId, ref: 'Test' },
         quantity: Number,
       }]
     });
     FooSchema.virtual('children.bar', {
-      ref: 'gh8198_Bar',
+      ref: 'Test',
       localField: 'children.barId',
       foreignField: '_id',
       justOne: true
     });
     const BarSchema = Schema({ name: String });
-    const Foo = db.model('gh8198_FooSchema', FooSchema);
-    const Bar = db.model('gh8198_Bar', BarSchema);
+    const Foo = db.model('Test1', FooSchema);
+    const Bar = db.model('Test', BarSchema);
     return co(function*() {
       const bar = yield Bar.create({ name: 'bar' });
       const foo = yield Foo.create({
@@ -8752,7 +8663,7 @@ describe('model: populate:', function() {
       });
       const pageSchema = Schema({ title: String, comments: [subSchema] });
       Author = db.model('Author', authorSchema);
-      Page = db.model('gh8247_Page', pageSchema);
+      Page = db.model('Test', pageSchema);
     });
 
     beforeEach(() => co(function*() {
@@ -8819,12 +8730,12 @@ describe('model: populate:', function() {
     });
 
     it('retainNullValues stores `null` in array if foreign doc not found (gh-8293)', function() {
-      const schema = Schema({ troops: [{ type: Number, ref: 'gh8293_Card' }] });
-      const Team = db.model('gh8293_Team', schema);
-
-      const Card = db.model('gh8293_Card', Schema({
+      db.deleteModel(/Test/);
+      const schema = Schema({ troops: [{ type: Number, ref: 'Test' }] });
+      const Team = db.model('Team', schema);
+      const Card = db.model('Test', Schema({
         _id: { type: Number },
-        name: { type: String, unique: true },
+        name: String,
         entityType: { type: String }
       }));
 
@@ -8849,20 +8760,21 @@ describe('model: populate:', function() {
     });
 
     it('virtual populate with discriminator that has a custom discriminator value (gh-8324)', function() {
+      db.deleteModel(/Test/);
       const mainSchema = new Schema({ title: { type: String } },
         { discriminatorKey: 'type' });
 
       mainSchema.virtual('virtualField', {
-        ref: 'gh8324_Model',
+        ref: 'Test1',
         localField: '_id',
         foreignField: 'main',
       });
 
       const discriminatedSchema = new Schema({ description: String });
-      const Main = db.model('gh8324_Main', mainSchema);
+      const Main = db.model('Test', mainSchema);
       const Discriminator = Main.discriminator('gh8324_Discriminator',
         discriminatedSchema, 'customValue');
-      const Model = db.model('gh8324_Model', Schema({
+      const Model = db.model('Test1', Schema({
         main: 'ObjectId'
       }));
 
@@ -8883,7 +8795,7 @@ describe('model: populate:', function() {
       });
 
       employeeSchema.virtual('department', {
-        ref: 'gh6608_Department',
+        ref: 'Test',
         localField: ['locationId', 'departmentId'],
         foreignField: ['locationId', 'name'],
         justOne: true
@@ -8895,8 +8807,8 @@ describe('model: populate:', function() {
       });
 
       return co(function*() {
-        const Employee = db.model('gh6608_Employee', employeeSchema);
-        const Department = db.model('gh6608_Department', departmentSchema);
+        const Employee = db.model('Person', employeeSchema);
+        const Department = db.model('Test', departmentSchema);
 
         yield Employee.create([
           { locationId: 'Miami', department: 'Engineering', name: 'Valeri Karpov' },
@@ -8923,13 +8835,13 @@ describe('model: populate:', function() {
     const companySchema = new mongoose.Schema({
       name: String
     });
-    const Company = db.model('gh8432_Companies', companySchema);
+    const Company = db.model('Test', companySchema);
 
     const userSchema = new mongoose.Schema({
       fullName: String,
       companyId: {
         type: mongoose.ObjectId,
-        ref: 'gh8432_Companies'
+        ref: 'Test'
       }
     });
     const User = db.model('User', userSchema);
@@ -8952,7 +8864,7 @@ describe('model: populate:', function() {
       title: String,
       files: { type: [fileSchema], default: [] }
     }, { toObject: { virtuals: true }, toJSON: { virtuals: true } });
-    const Ride = db.model('gh8432_Ride', rideSchema);
+    const Ride = db.model('Test1', rideSchema);
 
     return co(function*() {
       const company = yield Company.create({ name: 'Apple' });
@@ -8985,14 +8897,14 @@ describe('model: populate:', function() {
     });
 
     TestSchema.virtual('things', {
-      ref: 'gh8455_Thing',
+      ref: 'Test1',
       localField: 'thingIds',
       foreignField: '_id',
       justOne: false
     });
 
-    const Test = db.model('gh8455_Test', TestSchema);
-    db.model('gh8455_Thing', mongoose.Schema({ name: String }));
+    const Test = db.model('Test', TestSchema);
+    db.model('Test1', mongoose.Schema({ name: String }));
 
     return co(function*() {
       yield Test.collection.insertOne({});
@@ -9004,10 +8916,10 @@ describe('model: populate:', function() {
 
   it('succeeds with refPath if embedded discriminator has path with same name but no refPath (gh-8452) (gh-8499)', function() {
     const ImageSchema = Schema({ imageName: String });
-    const Image = db.model('gh8452_Image', ImageSchema);
+    const Image = db.model('Image', ImageSchema);
 
     const TextSchema = Schema({ textName: String });
-    const Text = db.model('gh8452_Text', TextSchema);
+    const Text = db.model('BlogPost', TextSchema);
 
     const opts = { _id: false };
     const ItemSchema = Schema({ objectType: String }, opts);
@@ -9026,7 +8938,7 @@ describe('model: populate:', function() {
     const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
     ExampleSchema.path('list').discriminator('gh8452_ExtendA', ItemSchemaA);
     ExampleSchema.path('list').discriminator('gh8452_ExtendB', ItemSchemaB);
-    const Example = db.model('gh8452_Example', ExampleSchema);
+    const Example = db.model('Test', ExampleSchema);
 
     return co(function*() {
       const images = yield Image.create([{ imageName: 'image' }, { imageName: 'image2' }]);
@@ -9034,10 +8946,10 @@ describe('model: populate:', function() {
       yield Example.create({
         test: '02',
         list: [
-          { __t: 'gh8452_ExtendA', data: images[0]._id, objectType: 'gh8452_Image' },
-          { __t: 'gh8452_ExtendA', data: text._id, objectType: 'gh8452_Text' },
+          { __t: 'gh8452_ExtendA', data: images[0]._id, objectType: 'Image' },
+          { __t: 'gh8452_ExtendA', data: text._id, objectType: 'BlogPost' },
           { __t: 'gh8452_ExtendB', data: { sourceId: 123 }, objectType: 'ExternalSourceA' },
-          { __t: 'gh8452_ExtendA', data: images[1]._id, objectType: 'gh8452_Image' },
+          { __t: 'gh8452_ExtendA', data: images[1]._id, objectType: 'Image' },
           { __t: 'gh8452_ExtendB', data: { sourceId: 456 }, objectType: 'ExternalSourceB' }
         ]
       });
@@ -9055,14 +8967,14 @@ describe('model: populate:', function() {
     const schema = Schema({ specialId: String });
 
     schema.virtual('searchResult', {
-      ref: 'gh8460_Result',
+      ref: 'Test',
       localField: 'specialId',
       foreignField: 'specialId',
       options: { select: 'name -_id -specialId' },
       justOne: true
     });
-    const Model = db.model('gh8460_Model', schema);
-    const Result = db.model('gh8460_Result', Schema({
+    const Model = db.model('Test1', schema);
+    const Result = db.model('Test', Schema({
       name: String,
       specialId: String,
       other: String

From 7872f7aa2e6cf7bd690c7b8edd6d16d37eb4961e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:32:33 +0200
Subject: [PATCH 0381/2348] Fixes #8487 Add set to SchemaType and inheerit

---
 .../schematype/getDefaultOptionSetter.js      |  8 -----
 lib/schema/array.js                           | 23 +++++++++++--
 lib/schema/boolean.js                         | 23 +++++++++++--
 lib/schema/buffer.js                          | 23 +++++++++++--
 lib/schema/date.js                            | 23 +++++++++++--
 lib/schema/decimal128.js                      | 23 +++++++++++--
 lib/schema/map.js                             |  8 +++--
 lib/schema/mixed.js                           | 23 +++++++++++--
 lib/schema/number.js                          | 23 +++++++++++--
 lib/schema/objectid.js                        | 23 +++++++++++--
 lib/schema/string.js                          | 23 +++++++++++--
 lib/schematype.js                             | 10 ++++--
 test/schema.type.test.js                      | 32 +++++++++++++++++++
 test/types.string.test.js                     | 29 -----------------
 14 files changed, 233 insertions(+), 61 deletions(-)
 delete mode 100644 lib/helpers/schematype/getDefaultOptionSetter.js
 delete mode 100644 test/types.string.test.js

diff --git a/lib/helpers/schematype/getDefaultOptionSetter.js b/lib/helpers/schematype/getDefaultOptionSetter.js
deleted file mode 100644
index 9266c240a62..00000000000
--- a/lib/helpers/schematype/getDefaultOptionSetter.js
+++ /dev/null
@@ -1,8 +0,0 @@
-'use strict';
-function getDefaultOptionSetter(type) {
-  return function setDefaultOption(optionName, value) {
-    type.defaultOptions[optionName] = value;
-  };
-}
-
-module.exports = getDefaultOptionSetter;
\ No newline at end of file
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 74d2d829fa1..475de969089 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -18,7 +18,6 @@ const utils = require('../utils');
 const castToNumber = require('./operators/helpers').castToNumber;
 const geospatial = require('./operators/geospatial');
 const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminatorByValue');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let MongooseArray;
 let EmbeddedDoc;
@@ -123,7 +122,6 @@ function SchemaArray(key, cast, options, schemaOptions) {
 SchemaArray.schemaName = 'Array';
 
 SchemaArray.defaultOptions = {};
-SchemaArray.setDefaultOption = getDefaultOptionSetter(SchemaArray);
 
 /**
  * Options for all arrays.
@@ -136,6 +134,27 @@ SchemaArray.setDefaultOption = getDefaultOptionSetter(SchemaArray);
 
 SchemaArray.options = { castNonArrays: true };
 
+/**
+ * Sets a default option for all Array instances.
+ *
+ * ####Example:
+ *
+ *     // Make all arrays have option `required` equal to true.
+ *     mongoose.Schema.Array.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Array }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaArray.set = SchemaType.set;
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 86804dbd8c5..4280d941f7e 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -8,7 +8,6 @@ const CastError = require('../error/cast');
 const SchemaType = require('../schematype');
 const castBoolean = require('../cast/boolean');
 const utils = require('../utils');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Boolean SchemaType constructor.
@@ -32,7 +31,6 @@ function SchemaBoolean(path, options) {
 SchemaBoolean.schemaName = 'Boolean';
 
 SchemaBoolean.defaultOptions = {};
-SchemaBoolean.setDefaultOption = getDefaultOptionSetter(SchemaBoolean);
 
 /*!
  * Inherits from SchemaType.
@@ -46,6 +44,27 @@ SchemaBoolean.prototype.constructor = SchemaBoolean;
 
 SchemaBoolean._cast = castBoolean;
 
+/**
+ * Sets a default option for all Boolean instances.
+ *
+ * ####Example:
+ *
+ *     // Make all booleans have `default` of false.
+ *     mongoose.Schema.Boolean.set('default', false);
+ *
+ *     const Order = mongoose.model('Order', new Schema({ isPaid: Boolean }));
+ *     new Order({ }).isPaid; // false
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaBoolean.set = SchemaType.set;
+
 /**
  * Get/set the function used to cast arbitrary values to booleans.
  *
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index b75328add28..81f03009177 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -11,7 +11,6 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const Binary = MongooseBuffer.Binary;
 const CastError = SchemaType.CastError;
@@ -39,7 +38,6 @@ function SchemaBuffer(key, options) {
 SchemaBuffer.schemaName = 'Buffer';
 
 SchemaBuffer.defaultOptions = {};
-SchemaBuffer.setDefaultOption = getDefaultOptionSetter(SchemaBuffer);
 
 /*!
  * Inherits from SchemaType.
@@ -54,6 +52,27 @@ SchemaBuffer.prototype.OptionsConstructor = SchemaBufferOptions;
 
 SchemaBuffer._checkRequired = v => !!(v && v.length);
 
+/**
+ * Sets a default option for all Buffer instances.
+ *
+ * ####Example:
+ *
+ *     // Make all buffers have `required` of true by default.
+ *     mongoose.Schema.Buffer.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Buffer }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaBuffer.set = SchemaType.set;
+
 /**
  * Override the function the required validator uses to check whether a string
  * passes the `required` check.
diff --git a/lib/schema/date.js b/lib/schema/date.js
index dd1849590db..c908430d28b 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -9,7 +9,6 @@ const SchemaDateOptions = require('../options/SchemaDateOptions');
 const SchemaType = require('../schematype');
 const castDate = require('../cast/date');
 const utils = require('../utils');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 
@@ -35,7 +34,6 @@ function SchemaDate(key, options) {
 SchemaDate.schemaName = 'Date';
 
 SchemaDate.defaultOptions = {};
-SchemaDate.setDefaultOption = getDefaultOptionSetter(SchemaDate);
 
 /*!
  * Inherits from SchemaType.
@@ -50,6 +48,27 @@ SchemaDate.prototype.OptionsConstructor = SchemaDateOptions;
 
 SchemaDate._cast = castDate;
 
+/**
+ * Sets a default option for all Date instances.
+ *
+ * ####Example:
+ *
+ *     // Make all dates have `required` of true by default.
+ *     mongoose.Schema.Date.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Date }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaDate.set = SchemaType.set;
+
 /**
  * Get/set the function used to cast arbitrary values to dates.
  *
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index 0520d2c0cc2..ca9bcb4737b 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -11,7 +11,6 @@ const castDecimal128 = require('../cast/decimal128');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let Document;
 
@@ -37,7 +36,6 @@ function Decimal128(key, options) {
 Decimal128.schemaName = 'Decimal128';
 
 Decimal128.defaultOptions = {};
-Decimal128.setDefaultOption = getDefaultOptionSetter(Decimal128);
 
 /*!
  * Inherits from SchemaType.
@@ -51,6 +49,27 @@ Decimal128.prototype.constructor = Decimal128;
 
 Decimal128._cast = castDecimal128;
 
+/**
+ * Sets a default option for all Decimal128 instances.
+ *
+ * ####Example:
+ *
+ *     // Make all decimal 128s have `required` of true by default.
+ *     mongoose.Schema.Decimal128.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: mongoose.Decimal128 }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+Decimal128.set = SchemaType.set;
+
 /**
  * Get/set the function used to cast arbitrary values to decimals.
  *
diff --git a/lib/schema/map.js b/lib/schema/map.js
index ee3b946a397..2db6bfc10b9 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -7,7 +7,6 @@
 const MongooseMap = require('../types/map');
 const SchemaMapOptions = require('../options/SchemaMapOptions');
 const SchemaType = require('../schematype');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 /*!
  * ignore
  */
@@ -17,8 +16,9 @@ class Map extends SchemaType {
     super(key, options, 'Map');
     this.$isSchemaMap = true;
   }
-  static setDefaultOption() {
-    return getDefaultOptionSetter(Map);
+
+  set(option,value) {
+    return SchemaType.set(option,value);
   }
 
   cast(val, doc, init) {
@@ -57,4 +57,6 @@ class Map extends SchemaType {
 
 Map.prototype.OptionsConstructor = SchemaMapOptions;
 
+Map.defaultOptions = {};
+
 module.exports = Map;
diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 36316f37a97..abea3530763 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -7,7 +7,6 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const utils = require('../utils');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Mixed SchemaType constructor.
@@ -46,7 +45,6 @@ function Mixed(path, options) {
 Mixed.schemaName = 'Mixed';
 
 Mixed.defaultOptions = {};
-Mixed.setDefaultOption = getDefaultOptionSetter(Mixed);
 
 /*!
  * Inherits from SchemaType.
@@ -74,6 +72,27 @@ Mixed.prototype.constructor = Mixed;
 
 Mixed.get = SchemaType.get;
 
+/**
+ * Sets a default option for all Mixed instances.
+ *
+ * ####Example:
+ *
+ *     // Make all mixed instances have `required` of true by default.
+ *     mongoose.Schema.Mixed.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: mongoose.Mixed }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+Mixed.set = SchemaType.set;
+
 /**
  * Casts `val` for Mixed.
  *
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 47158c9d16d..d868b4e581b 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -12,7 +12,6 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -50,6 +49,27 @@ function SchemaNumber(key, options) {
 
 SchemaNumber.get = SchemaType.get;
 
+/**
+ * Sets a default option for all Number instances.
+ *
+ * ####Example:
+ *
+ *     // Make all numbers have option `min` equal to 0.
+ *     mongoose.Schema.Number.set('min', 0);
+ *
+ *     const Order = mongoose.model('Order', new Schema({ amount: Number }));
+ *     new Order({ amount: -10 }).validateSync().errors.amount.message; // Path `amount` must be larger than 0.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaNumber.set = SchemaType.set;
+
 /*!
  * ignore
  */
@@ -104,7 +124,6 @@ SchemaNumber.cast = function cast(caster) {
 SchemaNumber.schemaName = 'Number';
 
 SchemaNumber.defaultOptions = {};
-SchemaNumber.setDefaultOption = getDefaultOptionSetter(SchemaNumber);
 
 /*!
  * Inherits from SchemaType.
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index bba8e62873b..aa7b4fb53c5 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -11,7 +11,6 @@ const oid = require('../types/objectid');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -47,7 +46,6 @@ function ObjectId(key, options) {
 ObjectId.schemaName = 'ObjectId';
 
 ObjectId.defaultOptions = {};
-ObjectId.setDefaultOption = getDefaultOptionSetter(ObjectId);
 
 /*!
  * Inherits from SchemaType.
@@ -76,6 +74,27 @@ ObjectId.prototype.OptionsConstructor = SchemaObjectIdOptions;
 
 ObjectId.get = SchemaType.get;
 
+/**
+ * Sets a default option for all ObjectId instances.
+ *
+ * ####Example:
+ *
+ *     // Make all object ids have option `required` equal to true.
+ *     mongoose.Schema.ObjectId.set('required', true);
+ *
+ *     const Order = mongoose.model('Order', new Schema({ userId: ObjectId }));
+ *     new Order({ }).validateSync().errors.userId.message; // Path `userId` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+ObjectId.set = SchemaType.set;
+
 /**
  * Adds an auto-generated ObjectId default if turnOn is true.
  * @param {Boolean} turnOn auto generated ObjectId defaults
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 17a5ce8c715..e0771bec065 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -11,7 +11,6 @@ const castString = require('../cast/string');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -40,7 +39,6 @@ function SchemaString(key, options) {
 SchemaString.schemaName = 'String';
 
 SchemaString.defaultOptions = {};
-SchemaString.setDefaultOption = getDefaultOptionSetter(SchemaString);
 
 /*!
  * Inherits from SchemaType.
@@ -120,6 +118,27 @@ SchemaString.cast = function cast(caster) {
 
 SchemaString.get = SchemaType.get;
 
+/**
+ * Sets a default option for all String instances.
+ *
+ * ####Example:
+ *
+ *     // Make all strings have option `trim` equal to true.
+ *     mongoose.Schema.String.set('trim', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ name: String }));
+ *     new User({ name: '   John Doe   ' }).name; // 'John Doe'
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaString.set = SchemaType.set;
+
 /*!
  * ignore
  */
diff --git a/lib/schematype.js b/lib/schematype.js
index 305ba3a6c55..757e358ca35 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -47,9 +47,9 @@ function SchemaType(path, options, instance) {
   const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
 
-  for (const optionName of defaultOptionsKeys) {
-    if (defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
-      options[optionName] = defaultOptions[optionName];
+  for (const option of defaultOptionsKeys) {
+    if (defaultOptions.hasOwnProperty(option) && !options.hasOwnProperty(option)) {
+      options[option] = defaultOptions[option];
     }
   }
 
@@ -149,6 +149,10 @@ SchemaType.cast = function cast(caster) {
   return this._cast;
 };
 
+SchemaType.set = function set(option, value) {
+  this.defaultOptions[option] = value;
+};
+
 /**
  * Attaches a getter for all instances of this schema type.
  *
diff --git a/test/schema.type.test.js b/test/schema.type.test.js
index d217615f3ce..344e35320f7 100644
--- a/test/schema.type.test.js
+++ b/test/schema.type.test.js
@@ -100,4 +100,36 @@ describe('schematype', function() {
     assert.equal(err.name, 'ValidatorError');
     assert.equal(err.message, 'name is invalid!');
   });
+
+  describe('set()', function() {
+    describe('SchemaType.set()', function() {
+      it('SchemaType.set, is a function', () => {
+        assert.equal(typeof mongoose.SchemaType.set, 'function');
+      });
+    });
+
+    const mongooseInstance = new mongoose.Mongoose();
+
+    [
+      mongoose.SchemaTypes.String,
+      mongoose.SchemaTypes.Number,
+      mongoose.SchemaTypes.Boolean,
+      mongoose.SchemaTypes.Array,
+      mongoose.SchemaTypes.Buffer,
+      mongoose.SchemaTypes.Date,
+      mongoose.SchemaTypes.ObjectId,
+      mongoose.SchemaTypes.Mixed,
+      mongoose.SchemaTypes.Decimal128,
+      mongoose.SchemaTypes.Map
+    ].forEach((type) => {
+      it(type.name + ', when given a default option, set its', () => {
+        // Act
+        type.set('required', true);
+        const schema = new mongooseInstance.Schema({test: type});
+
+        // Assert
+        assert.equal(schema.path('test').options.required, true);
+      });
+    });
+  });
 });
diff --git a/test/types.string.test.js b/test/types.string.test.js
deleted file mode 100644
index 390fd184b0b..00000000000
--- a/test/types.string.test.js
+++ /dev/null
@@ -1,29 +0,0 @@
-'use strict';
-
-/**
- * Module dependencies.
- */
-
-const mongoose = require('./common').mongoose;
-
-const assert = require('assert');
-
-/**
- * Test.
- */
-
-describe('types.string', function() {
-  describe('Schema.Types.String.setDefaultOptions(...)', function() {
-    it('when given an option, sets it', () => {
-      // Arrange
-      const mongooseInstance = new mongoose.Mongoose();
-
-      // Act
-      mongooseInstance.Schema.Types.String.setDefaultOption('trim',true);
-      const userSchema = new mongooseInstance.Schema({name:{type:String}});
-
-      // Assert
-      assert.equal(userSchema.path('name').options.trim, true);
-    });
-  });
-});

From a9c2799722539b9addd20ee633edfa138361a077 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:37:35 +0200
Subject: [PATCH 0382/2348] Add default settings to a new mongoose instance

---
 test/schema.type.test.js | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/test/schema.type.test.js b/test/schema.type.test.js
index 344e35320f7..8eb0de86a8a 100644
--- a/test/schema.type.test.js
+++ b/test/schema.type.test.js
@@ -111,16 +111,15 @@ describe('schematype', function() {
     const mongooseInstance = new mongoose.Mongoose();
 
     [
-      mongoose.SchemaTypes.String,
-      mongoose.SchemaTypes.Number,
-      mongoose.SchemaTypes.Boolean,
-      mongoose.SchemaTypes.Array,
-      mongoose.SchemaTypes.Buffer,
-      mongoose.SchemaTypes.Date,
-      mongoose.SchemaTypes.ObjectId,
-      mongoose.SchemaTypes.Mixed,
-      mongoose.SchemaTypes.Decimal128,
-      mongoose.SchemaTypes.Map
+      mongooseInstance.SchemaTypes.String,
+      mongooseInstance.SchemaTypes.Number,
+      mongooseInstance.SchemaTypes.Boolean,
+      mongooseInstance.SchemaTypes.Buffer,
+      mongooseInstance.SchemaTypes.Date,
+      mongooseInstance.SchemaTypes.ObjectId,
+      mongooseInstance.SchemaTypes.Mixed,
+      mongooseInstance.SchemaTypes.Decimal128,
+      mongooseInstance.SchemaTypes.Map
     ].forEach((type) => {
       it(type.name + ', when given a default option, set its', () => {
         // Act

From 6efa496cd9bbe9ff6b96f420267f266ff1f50959 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:38:25 +0200
Subject: [PATCH 0383/2348] Remove .set from SchemaArray

---
 lib/schema/array.js | 23 -----------------------
 1 file changed, 23 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 475de969089..e32cff9bfc5 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -121,8 +121,6 @@ function SchemaArray(key, cast, options, schemaOptions) {
  */
 SchemaArray.schemaName = 'Array';
 
-SchemaArray.defaultOptions = {};
-
 /**
  * Options for all arrays.
  *
@@ -134,27 +132,6 @@ SchemaArray.defaultOptions = {};
 
 SchemaArray.options = { castNonArrays: true };
 
-/**
- * Sets a default option for all Array instances.
- *
- * ####Example:
- *
- *     // Make all arrays have option `required` equal to true.
- *     mongoose.Schema.Array.set('required', true);
- *
- *     const User = mongoose.model('User', new Schema({ test: Array }));
- *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
- *
- * @param {String} option - The option you'd like to set the value for
- * @param {*} value - value for option
- * @return {undefined}
- * @function set
- * @static
- * @api public
- */
-
-SchemaArray.set = SchemaType.set;
-
 /*!
  * Inherits from SchemaType.
  */

From f177d563fa6a182951642879f02c110c247fa67e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:48:09 +0200
Subject: [PATCH 0384/2348] Use a fake option for testing

---
 test/schema.type.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/schema.type.test.js b/test/schema.type.test.js
index 8eb0de86a8a..71c7c07e6a7 100644
--- a/test/schema.type.test.js
+++ b/test/schema.type.test.js
@@ -123,11 +123,11 @@ describe('schematype', function() {
     ].forEach((type) => {
       it(type.name + ', when given a default option, set its', () => {
         // Act
-        type.set('required', true);
+        type.set('someRandomOption', true);
         const schema = new mongooseInstance.Schema({test: type});
 
         // Assert
-        assert.equal(schema.path('test').options.required, true);
+        assert.equal(schema.path('test').options.someRandomOption, true);
       });
     });
   });

From 6c8b854884c674a08cac41a63db9445bc5ec2b23 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 08:03:03 +0200
Subject: [PATCH 0385/2348] Default options to an empty object

---
 lib/schematype.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/schematype.js b/lib/schematype.js
index 757e358ca35..47b3527fe33 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -44,6 +44,7 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
+  options = options || {};
   const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
 

From d62e141a86ecf404b67a567f6b74382059f4a4b3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jan 2020 16:36:53 -0500
Subject: [PATCH 0386/2348] chore: now working on 5.8.9

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index e2f80e7a092..8b64131eb4d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.8",
+  "version": "5.8.9-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 5b2b0e533324880fee5b853e40ec1cc3c500ec9d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jan 2020 16:37:00 -0500
Subject: [PATCH 0387/2348] docs(queries): clarify when to use queries versus
 aggregations

Fix #8494
---
 docs/queries.pug | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/docs/queries.pug b/docs/queries.pug
index c905222e14c..0917b5200d8 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -51,6 +51,7 @@ block content
       <li><a href="#connection-string-options">Connection String Options</a></li>
       <li><a href="#refs">References to other documents</a></li>
       <li><a href="#streaming">Streaming</a></li>
+      <li><a href="#versus-aggregation">Versus Aggregation</a></li>
     </ul>
 
     ### Executing
@@ -176,6 +177,48 @@ block content
     });
     ```
 
+    <h3 id="versus-aggregation"><a href="#versus-aggregation">Versus Aggregation</a></h3>
+
+    [Aggregation](https://mongoosejs.com/docs/api.html#aggregate_Aggregate) can
+    do many of the same things that queries can. For example, below is
+    how you can use `aggregate()` to find docs where `name.last = 'Ghost'`:
+
+    ```javascript
+    const docs = await Person.aggregate([{ $match: { 'name.last': 'Ghost' } }]);
+    ```
+
+    However, just because you can use `aggregate()` doesn't mean you should.
+    In general, you should use queries where possible, and only use `aggregate()`
+    when you absolutely need to.
+
+    Unlike query results, Mongoose does **not** [`hydrate()`](/docs/api/model.html#model_Model.hydrate)
+    aggregation results. Aggregation results are always POJOs, not Mongoose
+    documents.
+
+    ```javascript
+    const docs = await Person.aggregate([{ $match: { 'name.last': 'Ghost' } }]);
+
+    docs[0] instanceof mongoose.Document; // false
+    ```
+
+    Also, unlike query filters, Mongoose also doesn't
+    [cast](/docs/tutorials/query_casting.html) aggregation pipelines. That means
+    you're responsible for ensuring the values you pass in to an aggregation
+    pipeline have the correct type.
+
+    ```javascript
+    const doc = await Person.findOne();
+
+    const idString = doc._id.toString();
+
+    // Finds the `Person`, because Mongoose casts `idString` to an ObjectId
+    const queryRes = await Person.findOne({ _id: idString });
+
+    // Does **not** find the `Person`, because Mongoose doesn't cast aggregation
+    // pipelines.
+    const aggRes = await Person.aggregate([{ $match: { _id: idString } }])
+    ```
+
     <h3 id="next"><a href="#next">Next Up</a></h3>
 
     Now that we've covered `Queries`, let's take a look at [Validation](/docs/validation.html).

From a28515d1d0298e0b7ecce4bf721aaafdedc2d1d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jan 2020 16:40:33 -0500
Subject: [PATCH 0388/2348] chore: release 5.8.9

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index d1e079fe1fb..64019fdca27 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.8.9 / 2020-01-17
+==================
+ * fix(populate): skip populating embedded discriminator array values that don't have a `refPath` #8499
+ * docs(queries): clarify when to use queries versus aggregations #8494
+
 5.8.8 / 2020-01-14
 ==================
  * fix(model): allow using `lean` with `insertMany()` #8507 #8234 [ntsekouras](https://github.com/ntsekouras)
diff --git a/package.json b/package.json
index 8b64131eb4d..1dac6342e23 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.9-pre",
+  "version": "5.8.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 203be9d0bd48e06f0c7e80dd4aee0305b355b8d3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jan 2020 18:59:33 -0500
Subject: [PATCH 0389/2348] fix: upgrade to mongodb driver 3.5.1

Re: #8520
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 1dac6342e23..1ce7a6f0e63 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.4.1",
+    "mongodb": "3.5.1",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From 806bd650f051a88bc71290424fce41b59b9d655d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jan 2020 18:59:55 -0500
Subject: [PATCH 0390/2348] fix(connection): avoid listening to 'left' event if
 `useUnifiedTopology` is set

Re: #8520
---
 lib/connection.js | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index b2bf74d59f8..ef870dfddf3 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -715,9 +715,12 @@ Connection.prototype.openUri = function(uri, options, callback) {
       db.s.topology.on('reconnectFailed', function() {
         _this.emit('reconnectFailed');
       });
-      db.s.topology.on('left', function(data) {
-        _this.emit('left', data);
-      });
+
+      if (!options.useUnifiedTopology) {
+        db.s.topology.on('left', function(data) {
+          _this.emit('left', data);
+        });
+      }
       db.s.topology.on('joined', function(data) {
         _this.emit('joined', data);
       });
@@ -735,12 +738,16 @@ Connection.prototype.openUri = function(uri, options, callback) {
           _this.readyState = STATES.disconnected;
         });
       }
-      client.on('left', function() {
-        if (_this.readyState === STATES.connected &&
-            get(db, 's.topology.s.coreTopology.s.replicaSetState.topologyType') === 'ReplicaSetNoPrimary') {
-          _this.readyState = STATES.disconnected;
-        }
-      });
+
+      if (!options.useUnifiedTopology) {
+        client.on('left', function() {
+          if (_this.readyState === STATES.connected &&
+              get(db, 's.topology.s.coreTopology.s.replicaSetState.topologyType') === 'ReplicaSetNoPrimary') {
+            _this.readyState = STATES.disconnected;
+          }
+        });
+      }
+
       db.on('timeout', function() {
         _this.emit('timeout');
       });

From a0bcd01931562a15153dd657708b911e7341da54 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jan 2020 19:21:21 -0500
Subject: [PATCH 0391/2348] test: clean up some tests for #8520

---
 test/common.js          | 3 +--
 test/connection.test.js | 3 ++-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/common.js b/test/common.js
index c4252b7946f..7c6968b96d8 100644
--- a/test/common.js
+++ b/test/common.js
@@ -195,8 +195,7 @@ after(function(done) {
 
 module.exports.server = server = new Server('mongod', {
   port: 27000,
-  dbpath: './data/db/27000',
-  storageEngine: 'mmapv1'
+  dbpath: './data/db/27000'
 });
 
 beforeEach(function() {
diff --git a/test/connection.test.js b/test/connection.test.js
index f409b01ba1f..2a6842fe89d 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -228,6 +228,7 @@ describe('connections:', function() {
           }).
           then(function() {
             assert.equal(conn.readyState, conn.states.disconnected);
+            assert.equal(numConnected, 1);
             assert.equal(numDisconnected, 1);
             assert.equal(numReconnected, 0);
             assert.equal(numReconnect, 0);
@@ -1156,7 +1157,7 @@ describe('connections:', function() {
     const uri = 'mongodb://baddomain:27017/test';
 
     return mongoose.createConnection(uri, opts).then(() => assert.ok(false), err => {
-      assert.equal(err.message, 'Server selection timed out after 100 ms');
+      assert.equal(err.message, 'getaddrinfo ENOTFOUND baddomain baddomain:27017');
       assert.equal(err.name, 'MongooseTimeoutError');
     });
   });

From 6e2ba7933f83378b2e758ac68a67aeca0b166b7d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:16:37 -0500
Subject: [PATCH 0392/2348] test: consistently use v4.0.2 to work around flakey
 #8520 tests

---
 .travis.yml                                  |  7 ++--
 lib/connection.js                            |  8 ++---
 lib/error/{timeout.js => serverSelection.js} | 16 ++++-----
 lib/model.js                                 |  8 ++---
 test/connection.test.js                      |  6 ++--
 test/model.populate.test.js                  | 34 ++++++++++++++++++++
 6 files changed, 57 insertions(+), 22 deletions(-)
 rename lib/error/{timeout.js => serverSelection.js} (53%)

diff --git a/.travis.yml b/.travis.yml
index aff97053cdd..9e2d3fc5b59 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,12 +4,13 @@ node_js: [12, 11, 10, 9, 8, 7, 6, 5, 4]
 install:
   - travis_retry npm install
 before_script:
-  - wget http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.6.6.tgz
-  - tar -zxvf mongodb-linux-x86_64-3.6.6.tgz
+  - wget http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
+  - tar -zxvf mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
   - mkdir -p ./data/db/27017
   - mkdir -p ./data/db/27000
   - printf "\n--timeout 8000" >> ./test/mocha.opts
-  - ./mongodb-linux-x86_64-3.6.6/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+  - ./mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+  - export PATH=`pwd`:$PATH
   - sleep 2
 matrix:
   include:
diff --git a/lib/connection.js b/lib/connection.js
index ef870dfddf3..2ce751d0161 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -10,7 +10,7 @@ const Collection = require('./driver').get().Collection;
 const STATES = require('./connectionstate');
 const MongooseError = require('./error/index');
 const PromiseProvider = require('./promise_provider');
-const TimeoutError = require('./error/timeout');
+const ServerSelectionError = require('./error/serverSelection');
 const applyPlugins = require('./helpers/schema/applyPlugins');
 const get = require('./helpers/get');
 const mongodb = require('mongodb');
@@ -767,12 +767,12 @@ Connection.prototype.openUri = function(uri, options, callback) {
     });
   });
 
-  const timeout = new TimeoutError();
+  const serverSelectionError = new ServerSelectionError();
   this.$initialConnection = Promise.all([promise, parsePromise]).
     then(res => res[0]).
     catch(err => {
-      if (err != null && err.name === 'MongoTimeoutError') {
-        err = timeout.assimilateError(err);
+      if (err != null && err.name === 'MongoServerSelectionError') {
+        err = serverSelectionError.assimilateError(err);
       }
 
       if (this.listeners('error').length > 0) {
diff --git a/lib/error/timeout.js b/lib/error/serverSelection.js
similarity index 53%
rename from lib/error/timeout.js
rename to lib/error/serverSelection.js
index 4f15d9038bc..7e6a1281e80 100644
--- a/lib/error/timeout.js
+++ b/lib/error/serverSelection.js
@@ -7,7 +7,7 @@
 const MongooseError = require('./mongooseError');
 
 /**
- * MongooseTimeoutError constructor
+ * MongooseServerSelectionError constructor
  *
  * @param {String} type
  * @param {String} value
@@ -15,9 +15,9 @@ const MongooseError = require('./mongooseError');
  * @api private
  */
 
-function MongooseTimeoutError(message) {
+function MongooseServerSelectionError(message) {
   MongooseError.call(this, message);
-  this.name = 'MongooseTimeoutError';
+  this.name = 'MongooseServerSelectionError';
   if (Error.captureStackTrace) {
     Error.captureStackTrace(this);
   } else {
@@ -29,20 +29,20 @@ function MongooseTimeoutError(message) {
  * Inherits from MongooseError.
  */
 
-MongooseTimeoutError.prototype = Object.create(MongooseError.prototype);
-MongooseTimeoutError.prototype.constructor = MongooseError;
+MongooseServerSelectionError.prototype = Object.create(MongooseError.prototype);
+MongooseServerSelectionError.prototype.constructor = MongooseError;
 
 /*!
  * ignore
  */
 
-MongooseTimeoutError.prototype.assimilateError = function(err) {
+MongooseServerSelectionError.prototype.assimilateError = function(err) {
   this.message = err.message;
   Object.assign(this, err, {
-    name: 'MongooseTimeoutError'
+    name: 'MongooseServerSelectionError'
   });
 
   return this;
 };
 
-module.exports = MongooseTimeoutError;
+module.exports = MongooseServerSelectionError;
diff --git a/lib/model.js b/lib/model.js
index 87177db419b..af4aeac57b7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -18,8 +18,8 @@ const Query = require('./query');
 const RemoveOptions = require('./options/removeOptions');
 const SaveOptions = require('./options/saveOptions');
 const Schema = require('./schema');
+const ServerSelectionError = require('./error/serverSelection');
 const SkipPopulateValue = require('./helpers/populate/SkipPopulateValue');
-const TimeoutError = require('./error/timeout');
 const ValidationError = require('./error/validation');
 const VersionError = require('./error/version');
 const ParallelSaveError = require('./error/parallelSave');
@@ -4800,11 +4800,11 @@ Model.$handleCallbackError = function(callback) {
  */
 
 Model.$wrapCallback = function(callback) {
-  const timeout = new TimeoutError();
+  const serverSelectionError = new ServerSelectionError();
 
   return function(err) {
-    if (err != null && err.name === 'MongoTimeoutError') {
-      arguments[0] = timeout.assimilateError(err);
+    if (err != null && err.name === 'MongoServerSelectionError') {
+      arguments[0] = serverSelectionError.assimilateError(err);
     }
 
     return callback.apply(null, arguments);
diff --git a/test/connection.test.js b/test/connection.test.js
index 2a6842fe89d..2d2172b3d38 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1148,7 +1148,7 @@ describe('connections:', function() {
     return Model.create({ name: 'test' });
   });
 
-  it('throws a MongooseTimeoutError on server selection timeout (gh-8451)', () => {
+  it('throws a MongooseServerSelectionError on server selection timeout (gh-8451)', () => {
     const opts = {
       useNewUrlParser: true,
       useUnifiedTopology: true,
@@ -1157,8 +1157,8 @@ describe('connections:', function() {
     const uri = 'mongodb://baddomain:27017/test';
 
     return mongoose.createConnection(uri, opts).then(() => assert.ok(false), err => {
-      assert.equal(err.message, 'getaddrinfo ENOTFOUND baddomain baddomain:27017');
-      assert.equal(err.name, 'MongooseTimeoutError');
+      assert.ok(err.message.indexOf('baddomain') !== -1, err.message);
+      assert.equal(err.name, 'MongooseServerSelectionError');
     });
   });
 });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 4372377795e..abdc1b9152f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9027,4 +9027,38 @@ describe('model: populate:', function() {
       assert.equal(doc.childCount, 1);
     });
   });
+
+  it.skip('supports top-level skip and limit options (gh-8445)', function() {
+    const childSchema = Schema({ parentId: 'ObjectId', deleted: Boolean });
+
+    const parentSchema = Schema({ name: String });
+    parentSchema.virtual('childCount', {
+      ref: 'Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      justOne: false,
+      skip: 1,
+      limit: 2
+    });
+
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
+
+    return co(function*() {
+      const p = yield Parent.create({ name: 'test' });
+
+      yield Child.create([
+        { parentId: p._id },
+        { parentId: p._id, deleted: true },
+        { parentId: p._id, deleted: false }
+      ]);
+
+      let doc = yield Parent.findOne().populate('childCount');
+      assert.equal(doc.childCount, 2);
+
+      doc = yield Parent.findOne().
+        populate({ path: 'childCount', match: { deleted: true } });
+      assert.equal(doc.childCount, 1);
+    });
+  });
 });

From 622519133c9a24906d27d0c8123ded96b089f9fd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:18:50 -0500
Subject: [PATCH 0393/2348] chore: correct path re: #8520

---
 .travis.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 9e2d3fc5b59..5bdee1541db 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,8 +10,9 @@ before_script:
   - mkdir -p ./data/db/27000
   - printf "\n--timeout 8000" >> ./test/mocha.opts
   - ./mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
-  - export PATH=`pwd`:$PATH
+  - export PATH=`pwd`/mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/:$PATH
   - sleep 2
+  - mongod --version
 matrix:
   include:
     - name: "👕Linter"

From 65e042cf346e5c13cd9acac6b711e34a53ba9bfc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:29:37 -0500
Subject: [PATCH 0394/2348] fix: emit timeout on "connectionClosed" re: #8520

---
 lib/connection.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 2ce751d0161..24f336bee82 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -689,14 +689,16 @@ Connection.prototype.openUri = function(uri, options, callback) {
             const newDescription = ev.newDescription;
             if (newDescription.type === 'Standalone') {
               _handleReconnect();
-            } else if (newDescription.error != null &&
-              newDescription.error.name === 'MongoNetworkError' &&
-              newDescription.error.message.endsWith('timed out')) {
-              _this.emit('timeout');
             } else {
               _this.readyState = STATES.disconnected;
             }
           });
+
+          client.on('connectionClosed', ev => {
+            if (ev.reason === 'error') {
+              _this.emit('timeout');
+            }
+          });
         } else if (type.startsWith('ReplicaSet')) {
           db.on('close', function() {
             const type = get(db, 's.topology.s.description.type', '');

From e93df1e14bf04a8279e2ba997baeb05fdf69c762 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:49:38 -0500
Subject: [PATCH 0395/2348] fix(connection): emit timeout by checking on
 individual operation rather than listening for connection events

Re: #8520
---
 lib/connection.js       |  6 ------
 lib/model.js            |  5 +++++
 test/connection.test.js | 45 ++++++++++++++++++-----------------------
 3 files changed, 25 insertions(+), 31 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 24f336bee82..8aaf83b131f 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -693,12 +693,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
               _this.readyState = STATES.disconnected;
             }
           });
-
-          client.on('connectionClosed', ev => {
-            if (ev.reason === 'error') {
-              _this.emit('timeout');
-            }
-          });
         } else if (type.startsWith('ReplicaSet')) {
           db.on('close', function() {
             const type = get(db, 's.topology.s.description.type', '');
diff --git a/lib/model.js b/lib/model.js
index af4aeac57b7..6f8d99fff19 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4801,11 +4801,16 @@ Model.$handleCallbackError = function(callback) {
 
 Model.$wrapCallback = function(callback) {
   const serverSelectionError = new ServerSelectionError();
+  const _this = this;
 
   return function(err) {
     if (err != null && err.name === 'MongoServerSelectionError') {
       arguments[0] = serverSelectionError.assimilateError(err);
     }
+    console.log('Check', err)
+    if (err != null && err.name === 'MongoNetworkError' && err.message.endsWith('timed out')) {
+      _this.db.emit('timeout');
+    }
 
     return callback.apply(null, arguments);
   };
diff --git a/test/connection.test.js b/test/connection.test.js
index 2d2172b3d38..e3807978d28 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -326,13 +326,13 @@ describe('connections:', function() {
           catch(done);
       });
 
-      it('timeout (gh-4513)', function(done) {
+      it('timeout (gh-4513)', function() {
         this.timeout(60000);
 
         let numTimeout = 0;
         let numDisconnected = 0;
         const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest', {
-          socketTimeoutMS: 100,
+          socketTimeoutMS: 5000,
           poolSize: 1,
           useNewUrlParser: true
         });
@@ -347,29 +347,25 @@ describe('connections:', function() {
 
         const Model = conn.model('gh4513', new Schema());
 
-        conn.
-          then(function() {
-            assert.equal(conn.readyState, conn.states.connected);
-            return Model.create({});
-          }).
-          then(function() {
-            return Model.find({ $where: 'sleep(250) || true' });
-          }).
-          then(function() {
-            done(new Error('expected timeout'));
-          }).
-          catch(function(error) {
-            assert.ok(error);
-            assert.ok(error.message.indexOf('timed out'), error.message);
-            // TODO: if autoReconnect is false, we might not actually be
-            // connected. See gh-5634
-            assert.equal(conn.readyState, conn.states.connected);
-            assert.equal(numTimeout, 1);
-            assert.equal(numDisconnected, 0);
+        return co(function*() {
+          yield conn;
 
-            conn.close();
-            done();
-          });
+          assert.equal(conn.readyState, conn.states.connected);
+
+          yield Model.create({});
+
+          const error = yield Model.find({ $where: 'sleep(10000) || true' }).
+            then(() => assert.ok(false), err => err);
+          assert.ok(error);
+          assert.ok(error.message.indexOf('timed out'), error.message);
+          // TODO: if autoReconnect is false, we might not actually be
+          // connected. See gh-5634
+          assert.equal(conn.readyState, conn.states.connected);
+          assert.equal(numTimeout, 1);
+          assert.equal(numDisconnected, 0);
+
+          yield conn.close();
+        });
       });
     });
   });
@@ -1157,7 +1153,6 @@ describe('connections:', function() {
     const uri = 'mongodb://baddomain:27017/test';
 
     return mongoose.createConnection(uri, opts).then(() => assert.ok(false), err => {
-      assert.ok(err.message.indexOf('baddomain') !== -1, err.message);
       assert.equal(err.name, 'MongooseServerSelectionError');
     });
   });

From ede90f35c40acea61b4c608863d45656ad99dd09 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:53:06 -0500
Subject: [PATCH 0396/2348] chore: remove unnecessary log statement

---
 lib/model.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 6f8d99fff19..b5d373a8cd9 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4807,7 +4807,6 @@ Model.$wrapCallback = function(callback) {
     if (err != null && err.name === 'MongoServerSelectionError') {
       arguments[0] = serverSelectionError.assimilateError(err);
     }
-    console.log('Check', err)
     if (err != null && err.name === 'MongoNetworkError' && err.message.endsWith('timed out')) {
       _this.db.emit('timeout');
     }

From 974d7992f352fb2da887f13e89f2cec8f0b06d7b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:54:43 -0500
Subject: [PATCH 0397/2348] test(connection): hopefully make disconnect test
 more robust re: #8520, for some reason this test only fails in travis

---
 test/connection.test.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index e3807978d28..ecbc07a8fe9 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -190,7 +190,8 @@ describe('connections:', function() {
         let numReconnect = 0;
         let numTimeout = 0;
         let numClose = 0;
-        const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest?heartbeatfrequencyms=1000', {
+        const conn = mongoose.createConnection('mongodb://localhost:27000/mongoosetest', {
+          heartbeatFrequencyMS: 500,
           useNewUrlParser: true,
           useUnifiedTopology: true
         });
@@ -223,7 +224,7 @@ describe('connections:', function() {
           }).
           then(function() {
             return new Promise(function(resolve) {
-              setTimeout(function() { resolve(); }, 100);
+              setTimeout(function() { resolve(); }, 1000);
             });
           }).
           then(function() {

From 7b062e66eae49cff9b7fe5516c8fc3b364ffb709 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 11:58:29 -0500
Subject: [PATCH 0398/2348] chore: now working on 5.8.10

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 1dac6342e23..1fbf774bdc2 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.9",
+  "version": "5.8.10-pre",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 46eb8e4928b191266ad8085fe2fa4973a8979d7c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 12:26:34 -0500
Subject: [PATCH 0399/2348] test(document): repro #8512

---
 test/document.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 5b551df290e..c7cdd7409ec 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8505,4 +8505,22 @@ describe('document', function() {
       assert.equal(raw.foo.bar.baz.num, 1);
     });
   });
+
+  it('supports function for date min/max validator error (gh-8512)', function() {
+    const schema = Schema({
+      startDate: {
+        type: Date,
+        required: true,
+        min: [new Date('2020-01-01'), () => 'test'],
+      }
+    });
+
+    db.deleteModel(/Test/);
+    const Model = db.model('Test', schema);
+    const doc = new Model({ startDate: new Date('2019-06-01') });
+
+    const err = doc.validateSync();
+    assert.ok(err.errors['startDate']);
+    assert.equal(err.errors['startDate'].message, 'test');
+  });
 });

From 9bb8414713fc5dc9e9084887bf85242ec447cd03 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Jan 2020 12:27:05 -0500
Subject: [PATCH 0400/2348] fix(document): allow function as message for date
 min/max validator

Fix #8512
---
 lib/schema/date.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/schema/date.js b/lib/schema/date.js
index 3c9b9146f33..b2a65d12cde 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -217,7 +217,9 @@ SchemaDate.prototype.min = function(value, message) {
 
   if (value) {
     let msg = message || MongooseError.messages.Date.min;
-    msg = msg.replace(/{MIN}/, (value === Date.now ? 'Date.now()' : value.toString()));
+    if (typeof msg === 'string') {
+      msg = msg.replace(/{MIN}/, (value === Date.now ? 'Date.now()' : value.toString()));
+    }
     const _this = this;
     this.validators.push({
       validator: this.minValidator = function(val) {
@@ -277,7 +279,9 @@ SchemaDate.prototype.max = function(value, message) {
 
   if (value) {
     let msg = message || MongooseError.messages.Date.max;
-    msg = msg.replace(/{MAX}/, (value === Date.now ? 'Date.now()' : value.toString()));
+    if (typeof msg === 'string') {
+      msg = msg.replace(/{MAX}/, (value === Date.now ? 'Date.now()' : value.toString()));
+    }
     const _this = this;
     this.validators.push({
       validator: this.maxValidator = function(val) {

From e4c1ef81ff3237159b3358c2951691ebb4c62993 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 12:51:45 -0500
Subject: [PATCH 0401/2348] test(document): clean up some unnecessary extra
 collections re: #8481

---
 test/document.test.js | 194 ++++++++++++++++++++----------------------
 1 file changed, 94 insertions(+), 100 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index c7cdd7409ec..f3df348a972 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -1788,12 +1788,13 @@ describe('document', function() {
       let val;
       let M;
 
-      before(function(done) {
+      beforeEach(function(done) {
         const schema = new mongoose.Schema({v: Number});
         schema.virtual('thang').set(function(v) {
           val = v;
         });
 
+        db.deleteModel(/Test/);
         M = db.model('Test', schema);
         done();
       });
@@ -2557,15 +2558,7 @@ describe('document', function() {
   });
 
   describe('bug fixes', function() {
-    let db;
-
-    before(function() {
-      db = start();
-    });
-
-    after(function(done) {
-      db.close(done);
-    });
+    beforeEach(() => db.deleteModel(/.*/));
 
     it('single embedded schemas with populate (gh-3501)', function(done) {
       const PopulateMeSchema = new Schema({});
@@ -2610,7 +2603,7 @@ describe('document', function() {
       };
 
       const bandSchema = new Schema({leadSinger: personSchema});
-      const Band = db.model('gh3534', bandSchema);
+      const Band = db.model('Band', bandSchema);
 
       const gnr = new Band({leadSinger: {name: 'Axl Rose'}});
       assert.equal(gnr.leadSinger.firstName(), 'Axl');
@@ -2619,10 +2612,10 @@ describe('document', function() {
 
     it('single embedded schemas with models (gh-3535)', function(done) {
       const personSchema = new Schema({name: String});
-      const Person = db.model('gh3535_0', personSchema);
+      const Person = db.model('Person', personSchema);
 
       const bandSchema = new Schema({leadSinger: personSchema});
-      const Band = db.model('gh3535', bandSchema);
+      const Band = db.model('Band', bandSchema);
 
       const axl = new Person({name: 'Axl Rose'});
       const gnr = new Band({leadSinger: axl});
@@ -2650,7 +2643,7 @@ describe('document', function() {
       const personSchema = new Schema({name: String});
 
       const bandSchema = new Schema({guitarist: personSchema, name: String});
-      const Band = db.model('gh3596', bandSchema);
+      const Band = db.model('Band', bandSchema);
 
       const gnr = new Band({
         name: 'Guns N\' Roses',
@@ -2671,7 +2664,7 @@ describe('document', function() {
       const personSchema = new Schema({name: String});
 
       const bandSchema = new Schema({guitarist: personSchema, name: String});
-      const Band = db.model('gh3601', bandSchema);
+      const Band = db.model('Band', bandSchema);
 
       const gnr = new Band({
         name: 'Guns N\' Roses',
@@ -2692,7 +2685,7 @@ describe('document', function() {
       const personSchema = new Schema({name: String});
 
       const bandSchema = new Schema({guitarist: personSchema, name: String});
-      const Band = db.model('gh3642', bandSchema);
+      const Band = db.model('Band', bandSchema);
 
       const velvetRevolver = new Band({
         name: 'Velvet Revolver',
@@ -2718,7 +2711,7 @@ describe('document', function() {
       });
 
       const bandSchema = new Schema({guitarist: personSchema, name: String});
-      const Band = db.model('gh3679', bandSchema);
+      const Band = db.model('Band', bandSchema);
       const obj = {name: 'Guns N\' Roses', guitarist: {name: 'Slash'}};
 
       Band.create(obj, function(error) {
@@ -2738,7 +2731,7 @@ describe('document', function() {
         guitarist: personSchema,
         name: String
       });
-      const Band = db.model('gh3686', bandSchema);
+      const Band = db.model('Band', bandSchema);
       const obj = {
         name: 'Guns N\' Roses',
         guitarist: {name: 'Slash', realName: 'Saul Hudson'}
@@ -2772,7 +2765,7 @@ describe('document', function() {
         singleNested: SingleNestedSchema
       });
 
-      const Parent = db.model('gh3680', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
       const obj = {singleNested: {children: [{count: 0}]}};
       Parent.create(obj, function(error) {
         assert.ifError(error);
@@ -2786,7 +2779,7 @@ describe('document', function() {
       const childSchema = new Schema({child: childChildSchema});
       const parentSchema = new Schema({child: childSchema});
 
-      const Parent = db.model('gh3702', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
       const obj = {child: {child: {count: 0}}};
       Parent.create(obj, function(error) {
         assert.ok(error);
@@ -2801,7 +2794,7 @@ describe('document', function() {
         return true;
       });
 
-      const Test = db.model('gh3618', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const test = new Test();
 
@@ -2832,7 +2825,7 @@ describe('document', function() {
         }]
       });
 
-      const MyModel = db.model('gh3623', schema);
+      const MyModel = db.model('Test', schema);
 
       const doc = {array: [{2: {}}]};
       MyModel.collection.insertOne(doc, function(error) {
@@ -4577,7 +4570,7 @@ describe('document', function() {
           validate: () => false
         }
       });
-      const Parent = mongoose.model('Test', parentSchema);
+      const Parent = db.model('Test', parentSchema);
 
       const parentDoc = new Parent({});
 
@@ -5955,11 +5948,11 @@ describe('document', function() {
     it('Handles setting populated path set via `Document#populate()` (gh-7302)', function() {
       const authorSchema = new Schema({ name: String });
       const bookSchema = new Schema({
-        author: { type: mongoose.Schema.Types.ObjectId, ref: 'gh7302_Author' }
+        author: { type: mongoose.Schema.Types.ObjectId, ref: 'Author' }
       });
 
-      const Author = db.model('gh7302_Author', authorSchema);
-      const Book = db.model('gh7302_Book', bookSchema);
+      const Author = db.model('Author', authorSchema);
+      const Book = db.model('Book', bookSchema);
 
       return Author.create({ name: 'Victor Hugo' }).
         then(function(author) { return Book.create({ author: author._id }); }).
@@ -5988,7 +5981,7 @@ describe('document', function() {
         product: String
       }, { _id: false }));
 
-      const MyModel = db.model('gh5693', trackSchema);
+      const MyModel = db.model('Test', trackSchema);
 
       const doc = new MyModel({
         event: {
@@ -6031,13 +6024,13 @@ describe('document', function() {
           }
         }
       });
-      const Child = mongoose.model('gh6801_Child', childSchema);
+      const Child = mongoose.model('Child', childSchema);
 
       const parentSchema = new Schema({
         name: String,
         child: childSchema
       });
-      const Parent = mongoose.model('gh6801_Parent', parentSchema);
+      const Parent = mongoose.model('Parent', parentSchema);
 
       const child = new Child(/* name is required */);
       const parent = new Parent({ child: child });
@@ -6059,7 +6052,7 @@ describe('document', function() {
           required: function() { return this && this.field === undefined; }
         }
       });
-      const Model = db.model('gh6892', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({});
@@ -6083,7 +6076,7 @@ describe('document', function() {
         children: [ItemChildSchema]
       });
 
-      const ItemParent = db.model('gh3511', ItemParentSchema);
+      const ItemParent = db.model('Parent', ItemParentSchema);
 
       const p = new ItemParent({
         children: [{ name: 'test1' }, { name: 'test2' }]
@@ -6127,7 +6120,7 @@ describe('document', function() {
         assets: [assetSchema]
       });
 
-      const Person = db.model('gh7556', personSchema);
+      const Person = db.model('Person', personSchema);
 
       return co(function*() {
         yield Person.create({
@@ -6163,7 +6156,7 @@ describe('document', function() {
         next();
       });
 
-      const Main = db.model('gh5800', MainSchema);
+      const Main = db.model('Test', MainSchema);
 
       const doc = { a: { b: 'not the default', d: 'some value' }, e: 'e' };
       return Main.create(doc).
@@ -6194,7 +6187,7 @@ describe('document', function() {
 
       pageSchema.path('media').discriminator('photo', photoSchema);
 
-      const Page = db.model('gh6482_Page', pageSchema);
+      const Page = db.model('Test', pageSchema);
 
       return co(function*() {
         let doc = yield Page.create({
@@ -6230,7 +6223,7 @@ describe('document', function() {
 
       pageSchema.path('media').discriminator('photo', photoSchema);
 
-      const Page = db.model('gh6526_Page', pageSchema);
+      const Page = db.model('Test', pageSchema);
 
       return co(function*() {
         let doc = yield Page.create({
@@ -6268,7 +6261,7 @@ describe('document', function() {
         children: [childSchema]
       });
 
-      const Parent = db.model('gh5347', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Parent.create({
         name: 'test',
@@ -6310,7 +6303,7 @@ describe('document', function() {
         keywords: [String]
       });
 
-      const Artist = db.model('gh6155', artistSchema);
+      const Artist = db.model('Test', artistSchema);
 
       const artist = new Artist({ name: 'Motley Crue' });
       assert.deepEqual(artist.toObject().keywords, ['Motley', 'Crue']);
@@ -6348,7 +6341,7 @@ describe('document', function() {
         return called;
       }
 
-      const TestDefaultsWithFunction = db.model('gh6410', new Schema({
+      const TestDefaultsWithFunction = db.model('Test', new Schema({
         randomID: {type: Number, default: generateRandomID}
       }));
 
@@ -6367,7 +6360,7 @@ describe('document', function() {
 
     it('convertToFalse and convertToTrue (gh-6758)', function() {
       const TestSchema = new Schema({ b: Boolean });
-      const Test = db.model('gh6758', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       mongoose.Schema.Types.Boolean.convertToTrue.add('aye');
       mongoose.Schema.Types.Boolean.convertToFalse.add('nay');
@@ -6398,7 +6391,7 @@ describe('document', function() {
         return 'foobar' + v;
       });
 
-      const M = db.model('gh6779', schema);
+      const M = db.model('Test', schema);
       const test = new M();
 
       test.nested.arr.push({ key: 'value' });
@@ -6420,7 +6413,7 @@ describe('document', function() {
         child: child
       });
 
-      const M = db.model('gh6925', parent);
+      const M = db.model('Test', parent);
       const test = new M({
         child: {
           nested: {
@@ -6449,7 +6442,7 @@ describe('document', function() {
         }
       });
 
-      const TestModel = db.model('gh3793', TestSchema);
+      const TestModel = db.model('Test', TestSchema);
 
       return co(function*() {
         yield Promise.resolve(db);
@@ -6481,7 +6474,7 @@ describe('document', function() {
         child: ChildObjectSchema
       });
 
-      const Parent = db.model('gh4405', ParentObjectSchema);
+      const Parent = db.model('Parent', ParentObjectSchema);
 
       const p = new Parent({
         parentProperty1: 'abc',
@@ -6533,15 +6526,15 @@ describe('document', function() {
         sub: subSchema
       });
 
-      const Other = db.model('gh6390', otherSchema);
-      const Test = db.model('6h6390_2', schema);
+      const Other = db.model('Test1', otherSchema);
+      const Test = db.model('Test', schema);
 
       const other = new Other({ name: 'Nicole' });
 
       const test = new Test({
         name: 'abc',
         sub: {
-          my: 'gh6390',
+          my: 'Test1',
           other: other._id
         }
       });
@@ -6555,6 +6548,8 @@ describe('document', function() {
   });
 
   describe('clobbered Array.prototype', function() {
+    beforeEach(() => db.deleteModel(/.*/));
+
     afterEach(function() {
       delete Array.prototype.remove;
     });
@@ -6567,7 +6562,7 @@ describe('document', function() {
       });
 
       const schema = new Schema({ arr: [{ name: String }] });
-      const MyModel = db.model('gh6431', schema);
+      const MyModel = db.model('Test', schema);
 
       const doc = new MyModel();
       assert.deepEqual(doc.toObject().arr, []);
@@ -6586,7 +6581,7 @@ describe('document', function() {
           }]
         }
       });
-      const Model = db.model('gh6818', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({
@@ -6621,7 +6616,7 @@ describe('document', function() {
         })
       });
 
-      const Test = mongoose.model('gh6710', schema);
+      const Test = db.model('Test', schema);
 
       const doc = new Test({ nested: { num: 123 } });
       doc.nested = 123;
@@ -6648,7 +6643,7 @@ describe('document', function() {
       const Parent = new mongoose.Schema({
         children: [Child]
       });
-      const ParentModel = db.model('gh7242', Parent);
+      const ParentModel = db.model('Parent', Parent);
       const doc = new ParentModel({ children: false });
 
       return doc.save().then(
@@ -6662,7 +6657,7 @@ describe('document', function() {
   });
 
   it('does not save duplicate items after two saves (gh-6900)', function() {
-    const M = db.model('gh6900', {items: [{name: String}]});
+    const M = db.model('Test', {items: [{name: String}]});
     const doc = new M();
     doc.items.push({ name: '1' });
 
@@ -6692,7 +6687,7 @@ describe('document', function() {
       inner: [innerSchema]
     });
 
-    const Model = db.model('gh6931', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc2 = new Model();
@@ -6721,7 +6716,7 @@ describe('document', function() {
       }
     });
 
-    const Model = db.model('gh6944', schema);
+    const Model = db.model('Test', schema);
 
     const doc = new Model({ _id: 'test', foo: 'hello', bar: { a: 'world' } });
 
@@ -6735,7 +6730,7 @@ describe('document', function() {
     const BarSchema = new Schema({ bar: String }, { _id: false });
     const FooNestedSchema = new Schema({ foo: BarSchema });
 
-    const Model = db.model('gh7048', FooNestedSchema);
+    const Model = db.model('Test', FooNestedSchema);
 
     return co(function*() {
       const doc = yield Model.create({ foo: { bar: 'test' } });
@@ -6755,7 +6750,7 @@ describe('document', function() {
         error: mongoose.Schema.Types.Mixed,
         name: { type: String, required: true }
       });
-      const Model = db.model('gh7127', schema);
+      const Model = db.model('Test', schema);
 
       const doc = new Model();
 
@@ -6789,7 +6784,7 @@ describe('document', function() {
         name: String,
         child: ChildSchema
       });
-      const Parent = db.model('gh6802', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const parent = new Parent({ child: { child: {} } });
 
@@ -6814,7 +6809,7 @@ describe('document', function() {
       arr3: [Object]
     });
 
-    const Test = db.model('gh7109', schema);
+    const Test = db.model('Test', schema);
 
     const test = new Test({
       arr1: ['test1', { two: 'three' }, [4, 'five', 6]],
@@ -6835,7 +6830,7 @@ describe('document', function() {
       }
     });
 
-    const Test = db.model('gh7145', schema);
+    const Test = db.model('Test', schema);
 
     const doc = new Test({ name: 'not-a-uuid' });
     const error = doc.validateSync();
@@ -6861,7 +6856,7 @@ describe('document', function() {
       }
     });
 
-    const Test = db.model('gh7145_0', schema);
+    const Test = db.model('Test', schema);
 
     const doc = new Test({ name: 'foo' });
     const error = doc.validateSync();
@@ -6883,7 +6878,7 @@ describe('document', function() {
 
     const TestSchema = new Schema({ subdocs: [InnerSchema] });
 
-    const Test = db.model('gh7187', TestSchema);
+    const Test = db.model('Test', TestSchema);
 
     return Test.create({ subdocs: [{ name: 'foo' }] }).then(
       () => { throw new Error('Fail'); },
@@ -6906,7 +6901,7 @@ describe('document', function() {
 
     const TestSchema = new Schema({ nested: InnerSchema });
 
-    const Model = db.model('gh7196', TestSchema);
+    const Model = db.model('Test', TestSchema);
 
     const doc = new Model({ nested: { name: 'foo' } });
 
@@ -6922,7 +6917,7 @@ describe('document', function() {
 
   it('should enable key with dot(.) on mixed types with checkKeys (gh-7144)', function() {
     const s = new Schema({ raw: { type: Schema.Types.Mixed } });
-    const M = db.model('gh7144', s);
+    const M = db.model('Test', s);
 
     const raw = { 'foo.bar': 'baz' };
 
@@ -6949,7 +6944,7 @@ describe('document', function() {
     const schema = new mongoose.Schema({
       sub: [subSchema]
     });
-    const Model = db.model('gh7227', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let doc = new Model({ name: 'test', sub: [{}] });
@@ -6980,7 +6975,7 @@ describe('document', function() {
       }
     });
 
-    const Account = db.model('gh7337', accountSchema);
+    const Account = db.model('Test', accountSchema);
 
     return co(function*() {
       yield Account.create({});
@@ -7014,7 +7009,7 @@ describe('document', function() {
     schema.pre('remove', () => ++removeCount1);
     schema.pre('remove', { document: true, query: false }, () => ++removeCount2);
 
-    const Model = db.model('gh7133', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc = new Model({ name: 'test' });
@@ -7054,7 +7049,7 @@ describe('document', function() {
       sub: subSchema
     });
 
-    const Model = db.model('gh7264', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const date = '2018-11-22T09:00:00.000Z';
@@ -7095,7 +7090,7 @@ describe('document', function() {
       },
     };
 
-    const Event = db.model('gh7271', EventSchema);
+    const Event = db.model('Test', EventSchema);
     const event = new Event(data, null);
 
     assert.equal(event.activity.name, 'Activity name');
@@ -7112,7 +7107,7 @@ describe('document', function() {
       }
     }, { versionKey: false });
 
-    let Test = db.model('gh7274', schema);
+    let Test = db.model('Test', schema);
 
     let mapTest = new Test({});
     mapTest.test.set('key1', 'value1');
@@ -7127,8 +7122,8 @@ describe('document', function() {
     }, { versionKey: false });
     schema.set('toObject', { flattenMaps: true });
 
-    db.deleteModel('gh7274');
-    Test = db.model('gh7274', schema);
+    db.deleteModel('Test');
+    Test = db.model('Test', schema);
 
     mapTest = new Test({});
     mapTest.test.set('key1', 'value1');
@@ -7139,7 +7134,7 @@ describe('document', function() {
 
   it('`collection` property with strict: false (gh-7276)', function() {
     const schema = new Schema({}, { strict: false, versionKey: false });
-    const Model = db.model('gh7276', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let doc = new Model({ test: 'foo', collection: 'bar' });
@@ -7154,7 +7149,7 @@ describe('document', function() {
   });
 
   it('should validateSync() all elements in doc array (gh-6746)', function() {
-    const Model = db.model('gh6746', new Schema({
+    const Model = db.model('Test', new Schema({
       colors: [{
         name: { type: String, required: true },
         hex: { type: String, required: true }
@@ -7176,7 +7171,7 @@ describe('document', function() {
   it('handles fake constructor (gh-7290)', function() {
     const TestSchema = new Schema({ test: String });
 
-    const TestModel = db.model('gh7290', TestSchema);
+    const TestModel = db.model('Test', TestSchema);
 
     const badQuery = {
       test: {
@@ -7206,7 +7201,7 @@ describe('document', function() {
   it('handles fake __proto__ (gh-7290)', function() {
     const TestSchema = new Schema({ test: String, name: String });
 
-    const TestModel = db.model('gh7290_proto', TestSchema);
+    const TestModel = db.model('Test', TestSchema);
 
     const badQuery = JSON.parse('{"test":{"length":1000000000,"__proto__":[]}}');
 
@@ -7229,7 +7224,7 @@ describe('document', function() {
   it('cast error with string path set to array in db (gh-7619)', function() {
     const TestSchema = new Schema({ name: String });
 
-    const TestModel = db.model('gh7619', TestSchema);
+    const TestModel = db.model('Test', TestSchema);
 
     return co(function*() {
       yield TestModel.findOne();
@@ -7246,13 +7241,13 @@ describe('document', function() {
 
   it('doesnt crash if nested path with `get()` (gh-7316)', function() {
     const schema = new mongoose.Schema({ http: { get: Number } });
-    const Model = db.model('gh7316', schema);
+    const Model = db.model('Test', schema);
 
     return Model.create({ http: { get: 400 } }); // Should succeed
   });
 
   it('copies atomics from existing document array when setting doc array (gh-7472)', function() {
-    const Dog = db.model('gh7472', new mongoose.Schema({
+    const Dog = db.model('Test', new mongoose.Schema({
       name: String,
       toys: [{
         name: String
@@ -7293,7 +7288,7 @@ describe('document', function() {
       return this.save();
     };
 
-    const Catalog = db.model('gh7342', catalogSchema);
+    const Catalog = db.model('Test', catalogSchema);
 
     return co(function*() {
       let doc = yield Catalog.create({ name: 'test', sub: { name: 'foo' } });
@@ -7316,7 +7311,7 @@ describe('document', function() {
       last: String
     }, { _id: false });
 
-    const User = db.model('gh7585', new Schema({
+    const User = db.model('User', new Schema({
       name: {
         type: NameSchema,
         default: {}
@@ -7341,7 +7336,7 @@ describe('document', function() {
       }
     });
 
-    const CompanyUser = db.model('gh7645', companyUserSchema);
+    const CompanyUser = db.model('User', companyUserSchema);
 
     const cu = new CompanyUser({ profile: { name: 'foo', email: 'bar' } });
     cu.profile = Object.assign({}, cu.profile);
@@ -7367,7 +7362,7 @@ describe('document', function() {
     const parentSchema = new Schema({
       nested: schema
     });
-    const Model = db.model('gh7601', parentSchema);
+    const Model = db.model('Parent', parentSchema);
 
     return co(function*() {
       const doc = yield Model.create({
@@ -7391,7 +7386,7 @@ describe('document', function() {
     const pageSchema = new Schema({
       p: { type: [photoSchema], alias: 'photos' }
     });
-    const Page = db.model('gh7592', pageSchema);
+    const Page = db.model('Test', pageSchema);
 
     return co(function*() {
       const doc = yield Page.create({ p: [{ foo: 'test' }] });
@@ -7409,7 +7404,7 @@ describe('document', function() {
     const testSchema = new Schema({
       foo: { type: String, get: v => v.toLowerCase() }
     });
-    const Test = db.model('gh7233', testSchema);
+    const Test = db.model('Test', testSchema);
 
     const doc = new Test({ foo: 'Bar' });
     assert.equal(doc.foo, 'bar');
@@ -7430,7 +7425,7 @@ describe('document', function() {
     const parentSchema = new mongoose.Schema({
       child: childSchema
     });
-    const Test = db.model('gh7660', parentSchema);
+    const Test = db.model('Test', parentSchema);
 
     const test = new Test({
       child: {
@@ -7462,7 +7457,7 @@ describe('document', function() {
     }
 
     const schema = new Schema({ nested: { prop: String } });
-    const Model = db.model('gh7639', schema);
+    const Model = db.model('Test', schema);
 
     const doc = new Model({ nested: { prop: '1' } });
 
@@ -7475,7 +7470,7 @@ describe('document', function() {
 
   it('supports setting date properties with strict: false (gh-7907)', function() {
     const schema = Schema({}, { strict: false });
-    const SettingsModel = db.model('gh7907', schema);
+    const SettingsModel = db.model('Test', schema);
 
     const date = new Date();
     const obj = new SettingsModel({
@@ -7510,7 +7505,7 @@ describe('document', function() {
     pageSchema.path('elements').discriminator('block', blockElementSchema);
     pageSchema.path('elements').discriminator('text', textElementSchema);
 
-    const Page = db.model('gh7656', pageSchema);
+    const Page = db.model('Test', pageSchema);
     const page = new Page({
       elements: [
         { type: 'text', body: 'Page Title' },
@@ -7539,7 +7534,7 @@ describe('document', function() {
       mixed: {}
     });
 
-    const Model = db.model('gh5369', schema);
+    const Model = db.model('Test', schema);
     const doc = new Model({ subdoc: {}, docArr: [{}] });
 
     assert.ok(doc.nested.$isEmpty());
@@ -7600,7 +7595,7 @@ describe('document', function() {
       type: String,
     }, opts);
 
-    const IssueModel = mongoose.model('gh7704', IssueSchema);
+    const IssueModel = mongoose.model('Test', IssueSchema);
 
     const SubIssueSchema = new mongoose.Schema({
       checklist: [{
@@ -7628,7 +7623,7 @@ describe('document', function() {
         }
       }
     });
-    const Kitten = db.model('gh7719', kittySchema);
+    const Kitten = db.model('Test', kittySchema);
 
     const k = new Kitten({ name: 'Mr Sprinkles' });
     return k.save().then(() => assert.equal(called, 0));
@@ -7642,7 +7637,7 @@ describe('document', function() {
       }
     });
 
-    const TestModel = db.model('gh7720', NewSchema);
+    const TestModel = db.model('Test', NewSchema);
     const instance = new TestModel();
     instance.object = 'value';
 
@@ -7668,11 +7663,10 @@ describe('document', function() {
       position: geojsonSchema
     });
 
-    const GeoJson = db.model('gh7748_0', geojsonSchema);
-    const User = db.model('gh7748', userSchema);
+    const User = db.model('User', userSchema);
 
     return co(function*() {
-      const position = new GeoJson({
+      const position = {
         geometry: {
           type: 'Point',
           coordinates: [1.11111, 2.22222]
@@ -7680,7 +7674,7 @@ describe('document', function() {
         properties: {
           a: 'b'
         }
-      });
+      };
 
       const newUser = new User({
         position: position
@@ -7701,7 +7695,7 @@ describe('document', function() {
 
   it('does not convert array to object with strict: false (gh-7733)', function() {
     const ProductSchema = new mongoose.Schema({}, { strict: false });
-    const Product = db.model('gh7733', ProductSchema);
+    const Product = db.model('Test', ProductSchema);
 
     return co(function*() {
       yield Product.create({ arr: [{ test: 1 }, { test: 2 }] });
@@ -7714,7 +7708,7 @@ describe('document', function() {
 
   it('does not crash with array property named "undefined" (gh-7756)', function() {
     const schema = new Schema({ 'undefined': [String] });
-    const Model = db.model('gh7756_undefined', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc = yield Model.create({ 'undefined': ['foo'] });
@@ -7747,7 +7741,7 @@ describe('document', function() {
       }
     });
 
-    const Parent = db.model('gh7792', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     const obj = { nested: { child: { name: 'foo' }, arr: [{ name: 'bar' }] } };
     return Parent.create(obj).then(() => {
@@ -7768,7 +7762,7 @@ describe('document', function() {
         }
       }
     });
-    const Model = db.model('gh4913', schema);
+    const Model = db.model('Test', schema);
 
     return Model.create({ name: 'foo' }).then(() => assert.ok(false), err => {
       assert.equal(err.errors['name'].message, 'Oops!');
@@ -7778,7 +7772,7 @@ describe('document', function() {
 
   it('handles nested properties named `schema` (gh-7831)', function() {
     const schema = new mongoose.Schema({ nested: { schema: String } });
-    const Model = db.model('gh7831', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.collection.insertOne({ nested: { schema: 'test' } });

From 9eb0c2b84775b5551707bbba8b9cc3b231195b83 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 12:59:56 -0500
Subject: [PATCH 0402/2348] test: fix some tests re: #8481

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 719f9d7a6fe..3087ef3b346 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -3321,7 +3321,7 @@ describe('Model', function() {
           embeds: [EmbeddedSchema]
         });
 
-        mongoose.model('Parent', ParentSchema);
+        db.model('Parent', ParentSchema);
 
         const Parent = db.model('Parent');
 

From a36776c8160fc0eebd0730ef816af6ce2fdb2584 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 13:03:52 -0500
Subject: [PATCH 0403/2348] test(populate): fix up flakey test re: #8481

---
 test/model.populate.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 4372377795e..bebcb262f69 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -562,13 +562,13 @@ describe('model: populate:', function() {
         assert.ifError(error);
         sample.save(function(error) {
           assert.ifError(error);
-          next();
+          next(sample._id);
         });
       });
     });
 
-    function next() {
-      Sample.findOne({}, function(error, sample) {
+    function next(_id) {
+      Sample.findOne({ _id }, function(error, sample) {
         assert.ifError(error);
         const opts = { path: 'items.company', options: { lean: true } };
         Company.populate(sample, opts, function(error) {

From 14be10174e5b88c69222220cf15643dc39ad6e07 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 13:21:30 -0500
Subject: [PATCH 0404/2348] test(document): clean up more unnecessary
 collections to speed up tests re: #8481

---
 test/document.test.js | 370 +++++++++++++++++++++---------------------
 1 file changed, 185 insertions(+), 185 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index f3df348a972..5f3be231136 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -1733,7 +1733,7 @@ describe('document', function() {
 
         it('allows positional syntax on mixed nested paths (gh-6738)', function() {
           const schema = new Schema({ nested: {} });
-          const M = mongoose.model('gh6738', schema);
+          const M = db.model('Test', schema);
           const doc = new M({
             'nested.x': 'foo',
             'nested.y': 42,
@@ -1749,7 +1749,7 @@ describe('document', function() {
             schedule: [new Schema({open: Number, close: Number})]
           });
 
-          const M = mongoose.model('Blog', schema);
+          const M = db.model('BlogPost', schema);
 
           const doc = new M({
             schedule: [{
@@ -2159,7 +2159,7 @@ describe('document', function() {
     });
 
     it('setters firing with objects on real paths (gh-2943)', function(done) {
-      const M = mongoose.model('gh2943', {
+      const M = db.model('Test', {
         myStr: {
           type: String, set: function(v) {
             return v.value;
@@ -2187,8 +2187,8 @@ describe('document', function() {
         const schema2 = new mongoose.Schema({
           email: String
         });
-        const Model1 = mongoose.model('gh-2782-1', schema1);
-        const Model2 = mongoose.model('gh-2782-2', schema2);
+        const Model1 = db.model('Test', schema1);
+        const Model2 = db.model('Test1', schema2);
 
         const doc1 = new Model1({'data.email': 'some@example.com'});
         assert.equal(doc1.data.email, 'some@example.com');
@@ -2205,7 +2205,7 @@ describe('document', function() {
           email: String
         }
       });
-      const Model1 = mongoose.model('gh3346', schema1);
+      const Model1 = db.model('Test', schema1);
 
       const doc1 = new Model1({'data.email': 'some@example.com'});
       assert.equal(doc1.data.email, 'some@example.com');
@@ -2215,7 +2215,7 @@ describe('document', function() {
     });
 
     it('doesnt attempt to cast generic objects as strings (gh-3030)', function(done) {
-      const M = mongoose.model('gh3030', {
+      const M = db.model('Test', {
         myStr: {
           type: String
         }
@@ -2439,7 +2439,7 @@ describe('document', function() {
         next(new Error('Catch all #2'));
       });
 
-      const Model = mongoose.model('gh2284', schema);
+      const Model = db.model('Test', schema);
 
       Model.create({}, function(error) {
         assert.ok(error);
@@ -2849,11 +2849,11 @@ describe('document', function() {
 
       const parentSchema = new Schema({
         name: String,
-        children: [{type: ObjectId, ref: 'gh3753'}]
+        children: [{type: ObjectId, ref: 'Child'}]
       });
 
-      const Child = db.model('gh3753', childSchema);
-      const Parent = db.model('gh3753_0', parentSchema);
+      const Child = db.model('Child', childSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Child.create({name: 'Luke Skywalker'}, function(error, child) {
         assert.ifError(error);
@@ -2877,10 +2877,10 @@ describe('document', function() {
         _id: Number,
         name: String,
         age: Number,
-        friends: [{type: Number, ref: 'gh3776'}]
+        friends: [{type: Number, ref: 'Person'}]
       });
 
-      const Person = db.model('gh3776', personSchema);
+      const Person = db.model('Person', personSchema);
 
       const people = [
         {_id: 0, name: 'Alice'},
@@ -2912,7 +2912,7 @@ describe('document', function() {
         }]
       });
 
-      const M = mongoose.model('gh3867', testSchema);
+      const M = db.model('Test', testSchema);
 
       const doc = M({
         things: [{}]
@@ -2932,11 +2932,11 @@ describe('document', function() {
 
       const userSchema = new mongoose.Schema({
         name:  String,
-        company: { type: mongoose.Schema.Types.ObjectId, ref: 'gh3873' }
+        company: { type: mongoose.Schema.Types.ObjectId, ref: 'Company' }
       });
 
-      const Company = db.model('gh3873', companySchema);
-      const User = db.model('gh3873_0', userSchema);
+      const Company = db.model('Company', companySchema);
+      const User = db.model('User', userSchema);
 
       const company = new Company({ name: 'IniTech', userCnt: 1 });
       const user = new User({ name: 'Peter', company: company._id });
@@ -2971,7 +2971,7 @@ describe('document', function() {
         child: childSchema
       });
 
-      const Parent = db.model('gh3880', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
       const p = new Parent({
         name: 'Mufasa',
         child: {
@@ -3009,7 +3009,7 @@ describe('document', function() {
         child: ChildSchema
       });
 
-      const Parent = db.model('gh3910', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const p = new Parent({
         name: 'Darth Vader',
@@ -3030,7 +3030,7 @@ describe('document', function() {
         pre: String,
         post: String
       }, { versionKey: false });
-      const MyModel = db.model('gh3902', schema);
+      const MyModel = db.model('Test', schema);
 
       MyModel.create({ pre: 'test', post: 'test' }, function(error, doc) {
         assert.ifError(error);
@@ -3045,18 +3045,18 @@ describe('document', function() {
         field: String
       });
 
-      const NestedModel = db.model('gh3982', NestedModelSchema);
+      const NestedModel = db.model('Test', NestedModelSchema);
 
       const ModelSchema = new mongoose.Schema({
         field: String,
         array: [{
           type: mongoose.Schema.ObjectId,
-          ref: 'gh3982',
+          ref: 'Test',
           required: true
         }]
       });
 
-      const Model = db.model('gh3982_0', ModelSchema);
+      const Model = db.model('Test1', ModelSchema);
 
       const nestedModel = new NestedModel({
         'field': 'nestedModel'
@@ -3084,7 +3084,7 @@ describe('document', function() {
         name: String
       });
 
-      const ChildModel = db.model('gh7070_Child', ChildModelSchema);
+      const ChildModel = db.model('Child', ChildModelSchema);
 
       const ParentModelSchema = new mongoose.Schema({
         model: String,
@@ -3092,13 +3092,13 @@ describe('document', function() {
         otherId: mongoose.ObjectId
       });
 
-      const ParentModel = db.model('gh7070', ParentModelSchema);
+      const ParentModel = db.model('Parent', ParentModelSchema);
 
       return co(function*() {
         const child = yield ChildModel.create({ name: 'test' });
 
         let parent = yield ParentModel.create({
-          model: 'gh7070_Child',
+          model: 'Child',
           childId: child._id
         });
 
@@ -3121,7 +3121,7 @@ describe('document', function() {
         child: childSchema
       });
 
-      const Parent = db.model('gh4008', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Parent.create({ child: { name: 'My child' } }, function(error, doc) {
         assert.ifError(error);
@@ -3153,7 +3153,7 @@ describe('document', function() {
       schema.add({ geo: geoSchema });
       schema.index({ geo: '2dsphere' });
 
-      const MyModel = db.model('gh4014', schema);
+      const MyModel = db.model('Test', schema);
 
       MyModel.on('index', function(err) {
         assert.ifError(err);
@@ -3175,7 +3175,7 @@ describe('document', function() {
           validate: function(v) { return !!v; }
         }
       });
-      const Model = db.model('gh4094', schema);
+      const Model = db.model('Test', schema);
       const m = new Model();
       assert.ifError(m.validateSync());
       done();
@@ -3189,7 +3189,7 @@ describe('document', function() {
         }
       });
 
-      const Model = db.model('gh4109', schema);
+      const Model = db.model('Test', schema);
       const m = new Model();
       assert.ok(!m.names);
       m.save(function(error, m) {
@@ -3245,7 +3245,7 @@ describe('document', function() {
         children: [childSchema]
       });
 
-      const Model = db.model('gh5389', schema);
+      const Model = db.model('Test', schema);
 
       Model.
         create({
@@ -3281,7 +3281,7 @@ describe('document', function() {
         }
       });
 
-      const Parent = db.model('gh4115', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const p = new Parent();
       assert.equal(p.child.$parent, p);
@@ -3304,7 +3304,7 @@ describe('document', function() {
         child: ChildSchema
       });
 
-      const Parent = db.model('gh2348', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const doc = {
         children: [{ name: 'Jacen' }, { name: 'Jaina' }],
@@ -3329,7 +3329,7 @@ describe('document', function() {
 
     it('strings of length 12 are valid oids (gh-3365)', function(done) {
       const schema = new Schema({ myId: mongoose.Schema.Types.ObjectId });
-      const M = db.model('gh3365', schema);
+      const M = db.model('Test', schema);
       const doc = new M({ myId: 'blablablabla' });
       doc.validate(function(error) {
         assert.ifError(error);
@@ -3347,7 +3347,7 @@ describe('document', function() {
           cheese: Boolean
         }
       });
-      const Omelette = db.model('gh4182', omeletteSchema);
+      const Omelette = db.model('Test', omeletteSchema);
       const doc = new Omelette({
         topping: {
           meat: 'bacon',
@@ -3365,7 +3365,7 @@ describe('document', function() {
     it('emits cb errors on model for save (gh-3499)', function(done) {
       const testSchema = new Schema({ name: String });
 
-      const Test = db.model('gh3499', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.on('error', function(error) {
         assert.equal(error.message, 'fail!');
@@ -3388,7 +3388,7 @@ describe('document', function() {
         next();
       });
 
-      const Test = db.model('gh3499_0', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.on('error', function(error) {
         assert.equal(error.message, 'fail!');
@@ -3403,7 +3403,7 @@ describe('document', function() {
     it('emits cb errors on model for find() (gh-3499)', function(done) {
       const testSchema = new Schema({ name: String });
 
-      const Test = db.model('gh3499_1', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.on('error', function(error) {
         assert.equal(error.message, 'fail!');
@@ -3423,7 +3423,7 @@ describe('document', function() {
         next();
       });
 
-      const Test = db.model('gh3499_2', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.on('error', function(error) {
         assert.equal(error.message, 'fail!');
@@ -3452,7 +3452,7 @@ describe('document', function() {
         recurrence: RecurrenceSchema
       });
 
-      const Event = db.model('gh4216', EventSchema);
+      const Event = db.model('Test', EventSchema);
       const ev = new Event({
         name: 'test',
         recurrence: { frequency: 2, interval: 'days' }
@@ -3469,7 +3469,7 @@ describe('document', function() {
         email: { type: String, validate: validator.isEmail }
       });
 
-      const MyModel = db.model('gh4064', schema);
+      const MyModel = db.model('Test', schema);
 
       MyModel.create({ email: 'invalid' }, function(error) {
         assert.ok(error);
@@ -3487,7 +3487,7 @@ describe('document', function() {
         }
       });
 
-      const MyModel = db.model('gh4218', schema);
+      const MyModel = db.model('Test', schema);
 
       return co(function*() {
         let doc = yield MyModel.create({});
@@ -3507,7 +3507,7 @@ describe('document', function() {
         }
       });
 
-      const MyModel = db.model('gh6436', schema);
+      const MyModel = db.model('Test', schema);
 
       return co(function*() {
         let doc = yield MyModel.create({});
@@ -3523,7 +3523,7 @@ describe('document', function() {
         minimize: false
       });
 
-      const SomeModel = mongoose.model('somemodel', SomeModelSchema);
+      const SomeModel = db.model('Test', SomeModelSchema);
 
       try {
         new SomeModel({});
@@ -3535,7 +3535,7 @@ describe('document', function() {
 
     it('directModifiedPaths() (gh-7373)', function() {
       const schema = new Schema({ foo: String, nested: { bar: String } });
-      const Model = db.model('gh7373', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({ foo: 'original', nested: { bar: 'original' } });
@@ -3557,7 +3557,7 @@ describe('document', function() {
           child: childSchema
         });
 
-        const Parent = db.model('gh4224', parentSchema);
+        const Parent = db.model('Test', parentSchema);
         Parent.create({ child: { name: 'Jacen' } }, function(error, doc) {
           assert.ifError(error);
           doc.child = { name: 'Jaina' };
@@ -3615,7 +3615,7 @@ describe('document', function() {
           }]
         });
 
-        const Team = db.model('gh5904', teamSchema);
+        const Team = db.model('Team', teamSchema);
 
         const jedis = new Team({
           name: 'Jedis',
@@ -3653,7 +3653,7 @@ describe('document', function() {
             },
           },
         });
-        const M = db.model('gh7313', testSchema);
+        const M = db.model('Test', testSchema);
 
         const doc = new M({
           name: { first: 'A', last: 'B' },
@@ -3680,7 +3680,7 @@ describe('document', function() {
         child: childSchema
       });
 
-      const Parent = db.model('gh4369', parentSchema);
+      const Parent = db.model('Test', parentSchema);
       let remaining = 2;
 
       const doc = new Parent({ child: { name: 'Jacen' } });
@@ -3707,7 +3707,7 @@ describe('document', function() {
         }]
       });
       assert.doesNotThrow(function() {
-        db.model('gh4540', schema);
+        db.model('Test', schema);
       });
       done();
     });
@@ -3722,7 +3722,7 @@ describe('document', function() {
 
       parentSchema.path('child').default([{ name: 'test' }]);
 
-      const Parent = db.model('gh4390', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Parent.create({}, function(error, doc) {
         assert.ifError(error);
@@ -3741,7 +3741,7 @@ describe('document', function() {
         date: Date
       });
 
-      const Test = db.model('gh4404', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create({ date: new Date('invalid date') }, function(error) {
         assert.ok(error);
@@ -3762,7 +3762,7 @@ describe('document', function() {
         }
       });
 
-      const Parent = db.model('gh4472', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const p = new Parent();
       p.set('data.children.0', {
@@ -3779,7 +3779,7 @@ describe('document', function() {
         name: { type: String, required: true }
       });
 
-      const Test = db.model('gh4480', TestSchema);
+      const Test = db.model('Parent', TestSchema);
 
       return co(function*() {
         yield Test.create({ name: 'val' });
@@ -3806,7 +3806,7 @@ describe('document', function() {
         children: [childSchema]
       });
 
-      const Test = db.model('gh6152', testSchema);
+      const Test = db.model('Test', testSchema);
 
       return co(function*() {
         yield Test.create({
@@ -3844,7 +3844,7 @@ describe('document', function() {
         content: String
       });
 
-      const Model = db.model('gh4542', schema);
+      const Model = db.model('Test', schema);
 
       const object = new Model();
       object._id = {key1: 'foo', key2: 'bar'};
@@ -3875,7 +3875,7 @@ describe('document', function() {
         }
       });
 
-      const Model = db.model('gh4607', schema);
+      const Model = db.model('Test', schema);
 
       assert.doesNotThrow(function() {
         new Model({
@@ -3900,7 +3900,7 @@ describe('document', function() {
         }
       });
 
-      const M = db.model('gh4663', schema);
+      const M = db.model('Test', schema);
 
       new M({ child: { name: 'test' } }).validateSync();
       done();
@@ -3918,7 +3918,7 @@ describe('document', function() {
         }
       });
 
-      const M = db.model('gh4578', ParentSchema);
+      const M = db.model('Test', ParentSchema);
 
       M.create({ age: 45 }, function(error, doc) {
         assert.ifError(error);
@@ -3940,7 +3940,7 @@ describe('document', function() {
         }
       });
 
-      const Cat = db.model('gh5206', testSchema);
+      const Cat = db.model('Cat', testSchema);
 
       const kitty = new Cat({
         name: 'Test',
@@ -3963,10 +3963,10 @@ describe('document', function() {
     });
 
     it('toObject() does not depopulate top level (gh-3057)', function(done) {
-      const Cat = db.model('gh3057', { name: String });
-      const Human = db.model('gh3057_0', {
+      const Cat = db.model('Cat', { name: String });
+      const Human = db.model('Person', {
         name: String,
-        petCat: { type: mongoose.Schema.Types.ObjectId, ref: 'gh3057' }
+        petCat: { type: mongoose.Schema.Types.ObjectId, ref: 'Cat' }
       });
 
       const kitty = new Cat({ name: 'Zildjian' });
@@ -3982,7 +3982,7 @@ describe('document', function() {
         name: String,
         car: {
           type: Schema.Types.ObjectId,
-          ref: 'gh6313_Car'
+          ref: 'Car'
         }
       });
 
@@ -3994,8 +3994,8 @@ describe('document', function() {
         name: String
       });
 
-      const Car = db.model('gh6313_Car', carSchema);
-      const Person = db.model('gh6313_Person', personSchema);
+      const Car = db.model('Car', carSchema);
+      const Person = db.model('Person', personSchema);
 
       const car = new Car({
         name: 'Ford'
@@ -4029,7 +4029,7 @@ describe('document', function() {
         }
       });
 
-      const User = db.model('gh4654', UserSchema);
+      const User = db.model('User', UserSchema);
       User.create({ email: 'test' }, function(error) {
         assert.equal(error.errors['profile'].message, 'profile required');
         done();
@@ -4048,7 +4048,7 @@ describe('document', function() {
         company: companySchema
       });
 
-      const User = db.model('gh4676', userSchema);
+      const User = db.model('User', userSchema);
 
       const user = new User({ company: { name: 'Test' } });
       user.save(function(error) {
@@ -4090,7 +4090,7 @@ describe('document', function() {
         }
       });
 
-      const Shipment = db.model('gh4766', ShipmentSchema);
+      const Shipment = db.model('Test', ShipmentSchema);
       const doc = new Shipment({
         entity: {
           shipper: null,
@@ -4135,7 +4135,7 @@ describe('document', function() {
         name: String
       });
 
-      const User = db.model('gh4506', UserSchema);
+      const User = db.model('User', UserSchema);
 
       const user = new User({
         email: 'me@email.com',
@@ -4170,7 +4170,7 @@ describe('document', function() {
         nested: { type: [ NestedSchema ] }
       });
 
-      const Root = db.model('gh4681', RootSchema);
+      const Root = db.model('Test', RootSchema);
       const root = new Root({ rootName: 'root', nested: [ { } ] });
       root.save(function(error) {
         assert.ok(error);
@@ -4185,14 +4185,14 @@ describe('document', function() {
         name: String
       });
 
-      const ChildModel = db.model('gh4658', ChildSchema);
+      const ChildModel = db.model('Child', ChildSchema);
 
       const ParentSchema = new mongoose.Schema({
         name: String,
-        child: { type: Schema.Types.ObjectId, ref: 'gh4658' }
+        child: { type: Schema.Types.ObjectId, ref: 'Child' }
       }, {shardKey: {child: 1, _id: 1}});
 
-      const ParentModel = db.model('gh4658_0', ParentSchema);
+      const ParentModel = db.model('Parent', ParentSchema);
 
       ChildModel.create({ name: 'Luke' }).
         then(function(child) {
@@ -4239,7 +4239,7 @@ describe('document', function() {
         return this.children[0].get('favorites');
       });
 
-      const Parent = db.model('gh4716', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
       const p = new Parent({ name: 'Anakin' });
       p.set('children.0.name', 'Leah');
       p.set('favorites.color', 'Red');
@@ -4286,7 +4286,7 @@ describe('document', function() {
           required: false
         }
       });
-      const Model2 = db.model('gh4778', Model2Schema);
+      const Model2 = db.model('Test', Model2Schema);
 
       const doc = new Model2({
         sub: {}
@@ -4300,7 +4300,7 @@ describe('document', function() {
 
     it('timestamps set to false works (gh-7074)', function() {
       const schema = new Schema({ name: String }, { timestamps: false });
-      const Test = db.model('gh7074', schema);
+      const Test = db.model('Test', schema);
       return co(function*() {
         const doc = yield Test.create({ name: 'test' });
         assert.strictEqual(doc.updatedAt, undefined);
@@ -4316,7 +4316,7 @@ describe('document', function() {
         }
       });
 
-      const M = db.model('gh5051', schema);
+      const M = db.model('Test', schema);
       const now = Date.now();
       M.create({}, function(error, doc) {
         assert.ok(doc.props.createdAt);
@@ -4360,13 +4360,13 @@ describe('document', function() {
 
       schema.post('save', function(error, res, next) {
         assert.ok(error instanceof MongooseError.DocumentNotFoundError);
-        assert.ok(error.message.indexOf('gh4004') !== -1, error.message);
+        assert.ok(error.message.indexOf('Test') !== -1, error.message);
 
         error = new Error('Somebody else updated the document!');
         next(error);
       });
 
-      const MyModel = db.model('gh4004', schema);
+      const MyModel = db.model('Test', schema);
 
       MyModel.create({ name: 'test' }).
         then(function() {
@@ -4403,7 +4403,7 @@ describe('document', function() {
         }
       });
 
-      const Test = db.model('gh4800', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       Test.create({ buf: Buffer.from('abcd') }).
         then(function(doc) {
@@ -4425,7 +4425,7 @@ describe('document', function() {
         }
       });
 
-      const Test = db.model('gh5530', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       const doc = new Test({ uuid: 'test1' });
       assert.equal(doc.uuid._subtype, 4);
@@ -4449,7 +4449,7 @@ describe('document', function() {
         child: childSchema
       });
 
-      const Parent = db.model('gh3884', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const p = new Parent({
         name: 'Mufasa',
@@ -4489,7 +4489,7 @@ describe('document', function() {
         children: [childSchema]
       });
 
-      const Parent = db.model('gh5861', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const p = new Parent({
         name: 'Mufasa',
@@ -4537,7 +4537,7 @@ describe('document', function() {
       });
 
       return co(function*() {
-        const Parent = db.model('gh5885', parentSchema);
+        const Parent = db.model('Parent', parentSchema);
 
         const doc = yield Parent.create({
           child: {
@@ -4587,17 +4587,17 @@ describe('document', function() {
       grandchildSchema.method({
         foo: function() { return 'bar'; }
       });
-      const Grandchild = db.model('gh4793_0', grandchildSchema);
+      const Grandchild = db.model('Test', grandchildSchema);
 
       const childSchema = new mongoose.Schema({
         grandchild: grandchildSchema
       });
-      const Child = mongoose.model('gh4793_1', childSchema);
+      const Child = db.model('Child', childSchema);
 
       const parentSchema = new mongoose.Schema({
         children: [childSchema]
       });
-      const Parent = mongoose.model('gh4793_2', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const grandchild = new Grandchild();
       const child = new Child({grandchild: grandchild});
@@ -4644,7 +4644,7 @@ describe('document', function() {
         ++postBaz;
       });
 
-      const MyModel = db.model('gh6385', mySchema);
+      const MyModel = db.model('Test', mySchema);
 
       return co(function*() {
         const doc = new MyModel({ name: 'test' });
@@ -4688,7 +4688,7 @@ describe('document', function() {
         ++preBar;
       });
 
-      const MyModel = db.model('gh6385_1', mySchema);
+      const MyModel = db.model('Test', mySchema);
 
       return co(function*() {
         const doc = new MyModel({ name: 'test' });
@@ -4716,18 +4716,18 @@ describe('document', function() {
       commentSchema.methods.toString = function() {
         return `${this.constructor.modelName}(${this.title})`;
       };
-      const Comment = db.model('gh6538_Comment', commentSchema);
+      const Comment = db.model('Comment', commentSchema);
       const c = new Comment({ title: 'test' });
-      assert.strictEqual('gh6538_Comment(test)', `${c}`);
+      assert.strictEqual('Comment(test)', `${c}`);
       done();
     });
 
     it('setting to discriminator (gh-4935)', function(done) {
-      const Buyer = db.model('gh4935_0', new Schema({
+      const Buyer = db.model('Test1', new Schema({
         name: String,
-        vehicle: { type: Schema.Types.ObjectId, ref: 'gh4935' }
+        vehicle: { type: Schema.Types.ObjectId, ref: 'Test' }
       }));
-      const Vehicle = db.model('gh4935', new Schema({ name: String }));
+      const Vehicle = db.model('Test', new Schema({ name: String }));
       const Car = Vehicle.discriminator('gh4935_1', new Schema({
         model: String
       }));
@@ -4753,7 +4753,7 @@ describe('document', function() {
         }
       });
 
-      const M = db.model('gh2185', schema);
+      const M = db.model('Test', schema);
 
       const error = (new M({ name: 'test' })).validateSync();
       assert.ok(error);
@@ -4783,7 +4783,7 @@ describe('document', function() {
     it('save errors with callback and promise work (gh-5216)', function(done) {
       const schema = new mongoose.Schema({});
 
-      const Model = db.model('gh5216', schema);
+      const Model = db.model('Test', schema);
 
       const _id = new mongoose.Types.ObjectId();
       const doc1 = new Model({ _id: _id });
@@ -4816,7 +4816,7 @@ describe('document', function() {
         children: [ChildModelSchema]
       });
 
-      const Model = db.model('gh5085', ParentModelSchema);
+      const Model = db.model('Parent', ParentModelSchema);
 
       Model.create({ children: [{ text: 'test' }] }, function(error) {
         assert.ifError(error);
@@ -4842,7 +4842,7 @@ describe('document', function() {
         sub: subSchema
       });
 
-      const Test = db.model('gh6926', schema);
+      const Test = db.model('Test', schema);
 
       const test = new Test({ sub: { val: 'test' } });
 
@@ -4859,7 +4859,7 @@ describe('document', function() {
         }
       });
 
-      const Model = db.model('gh5008', schema);
+      const Model = db.model('Test', schema);
 
       const doc = new Model({
         sub: {
@@ -4886,7 +4886,7 @@ describe('document', function() {
         }
       });
 
-      const Model = db.model('gh5143', schema);
+      const Model = db.model('Test', schema);
 
       const model = new Model();
       model.customer = null;
@@ -4915,7 +4915,7 @@ describe('document', function() {
         }
       });
 
-      const Restaurant = db.model('gh5162', RestaurantSchema);
+      const Restaurant = db.model('Test', RestaurantSchema);
 
       // Should not throw
       const r = new Restaurant();
@@ -4935,7 +4935,7 @@ describe('document', function() {
         return Object.keys(this.nested).map(key => this.nested[key]);
       });
 
-      const M = db.model('gh5078', schema);
+      const M = db.model('Test', schema);
 
       const doc = new M({ nested: { test1: 'a', test2: 'b' } });
 
@@ -4959,7 +4959,7 @@ describe('document', function() {
           this.v = value;
         });
 
-      const TestModel = db.model('gh5250', TestSchema);
+      const TestModel = db.model('Test', TestSchema);
       const t = new TestModel({'a.b.c': 5});
       assert.equal(t.a.b.c, 5);
 
@@ -4976,15 +4976,15 @@ describe('document', function() {
       childSchema.virtual('nested.childVirtual').get(() => true);
 
       const parentSchema = Schema({
-        child: { type: Number, ref: 'gh7491_Child' }
+        child: { type: Number, ref: 'Child' }
       }, { toObject: { virtuals: true } });
 
       parentSchema.virtual('_nested').get(function() {
         return this.child.nested;
       });
 
-      const Child = db.model('gh7491_Child', childSchema);
-      const Parent = db.model('gh7491_Parent', parentSchema);
+      const Child = db.model('Child', childSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       return co(function*() {
         yield Child.create({
@@ -5071,7 +5071,7 @@ describe('document', function() {
         child: childSchema
       });
 
-      const Parent = db.model('gh5215', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Parent.create({ child: {} }, function(error) {
         assert.ok(error);
@@ -5094,7 +5094,7 @@ describe('document', function() {
         }
       });
 
-      const Test = db.model('gh4009', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create({}, function(error) {
         assert.ok(error);
@@ -5115,7 +5115,7 @@ describe('document', function() {
         strs: [[String]]
       });
 
-      const Test = db.model('gh5282', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const t = new Test({
         strs: [['a', 'b']]
@@ -5134,7 +5134,7 @@ describe('document', function() {
         array: [[{key: String, value: Number}]]
       });
 
-      const Model = db.model('gh6398', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({
@@ -5161,7 +5161,7 @@ describe('document', function() {
         array: [[[{key: String, value: Number}]]]
       });
 
-      const Model = db.model('gh6602', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({
@@ -5186,7 +5186,7 @@ describe('document', function() {
     it('null _id (gh-5236)', function(done) {
       const childSchema = new mongoose.Schema({});
 
-      const M = db.model('gh5236', childSchema);
+      const M = db.model('Test', childSchema);
 
       const m = new M({ _id: null });
       m.save(function(error, doc) {
@@ -5198,16 +5198,16 @@ describe('document', function() {
     it('setting populated path with typeKey (gh-5313)', function(done) {
       const personSchema = Schema({
         name: {$type: String},
-        favorite: { $type: Schema.Types.ObjectId, ref: 'gh5313' },
-        books: [{ $type: Schema.Types.ObjectId, ref: 'gh5313' }]
+        favorite: { $type: Schema.Types.ObjectId, ref: 'Book' },
+        books: [{ $type: Schema.Types.ObjectId, ref: 'Book' }]
       }, { typeKey: '$type' });
 
       const bookSchema = Schema({
         title: String
       });
 
-      const Book = mongoose.model('gh5313', bookSchema);
-      const Person = mongoose.model('gh5313_0', personSchema);
+      const Book = db.model('Book', bookSchema);
+      const Person = db.model('Person', personSchema);
 
       const book1 = new Book({ title: 'The Jungle Book' });
       const book2 = new Book({ title: '1984' });
@@ -5234,7 +5234,7 @@ describe('document', function() {
         }
       });
 
-      const M = db.model('gh5294', schema);
+      const M = db.model('Test', schema);
 
       M.create({ name: 'Test' }, function(error, doc) {
         assert.ifError(error);
@@ -5257,7 +5257,7 @@ describe('document', function() {
         }
       });
 
-      const Model = db.model('gh5296', schema);
+      const Model = db.model('Test', schema);
 
       Model.create({ name: undefined }, function(error) {
         assert.ifError(error);
@@ -5277,7 +5277,7 @@ describe('document', function() {
         return 2;
       });
 
-      const Model = mongoose.model('gh5473', schema);
+      const Model = db.model('Test', schema);
 
       const m = new Model({});
       assert.deepEqual(m.toJSON().test, {
@@ -5304,7 +5304,7 @@ describe('document', function() {
         }
       });
 
-      const Parent = db.model('gh5506', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const p = new Parent({ child: { name: 'myName' } });
 
@@ -5334,7 +5334,7 @@ describe('document', function() {
         },
         department: String
       });
-      const Employee = mongoose.model('gh5470', employeeSchema);
+      const Employee = db.model('Test', employeeSchema);
 
       const employee = new Employee({
         name: {
@@ -5374,7 +5374,7 @@ describe('document', function() {
         }
       });
 
-      const User = db.model('gh5523', userSchema);
+      const User = db.model('User', userSchema);
 
       const user = new User({
         social: {
@@ -5425,7 +5425,7 @@ describe('document', function() {
         body: contentSchema
       });
 
-      const Note = db.model('gh5363', noteSchema);
+      const Note = db.model('Test', noteSchema);
 
       const note = new Note({
         title: 'Lorem Ipsum Dolor',
@@ -5476,7 +5476,7 @@ describe('document', function() {
         options: optionsSchema
       });
 
-      const Test = db.model('gh5406', TestSchema);
+      const Test = db.model('Test', TestSchema);
 
       const doc = new Test({
         fieldOne: 'Test One',
@@ -5533,7 +5533,7 @@ describe('document', function() {
         body: { type: contentSchema }
       });
 
-      const Note = db.model('gh5388', noteSchema);
+      const Note = db.model('Test', noteSchema);
 
       const note = new Note({
         title: 'Lorem Ipsum Dolor',
@@ -5559,11 +5559,11 @@ describe('document', function() {
       const ReferringSchema = new Schema({
         reference: [{
           type: Schema.Types.ObjectId,
-          ref: 'gh5504'
+          ref: 'Test'
         }]
       });
 
-      const Referrer = db.model('gh5504', ReferringSchema);
+      const Referrer = db.model('Test', ReferringSchema);
 
       const referenceA = new Referrer();
       const referenceB = new Referrer();
@@ -5614,7 +5614,7 @@ describe('document', function() {
         }
       });
 
-      const SuperDocument = db.model('gh5569', SuperDocumentSchema);
+      const SuperDocument = db.model('Test', SuperDocumentSchema);
 
       let doc = new SuperDocument();
       doc.thing.undefinedDisallowed = null;
@@ -5652,7 +5652,7 @@ describe('document', function() {
         }
       });
 
-      const Parent = db.model('gh5601', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
       const p = new Parent();
       p.child = { number: '555.555.0123' };
       assert.equal(vals.length, 1);
@@ -5676,7 +5676,7 @@ describe('document', function() {
       const schema = new Schema({
         name: childSchema
       });
-      const Model = db.model('gh7442', schema);
+      const Model = db.model('Test', schema);
 
       const doc = new Model({ 'name.value': 'test' });
 
@@ -5699,8 +5699,8 @@ describe('document', function() {
         }]
       });
       const RelatedSchema = new Schema({ name: { type: String } });
-      const Model = db.model('gh5632', MainSchema);
-      const RelatedModel = db.model('gh5632_0', RelatedSchema);
+      const Model = db.model('Test', MainSchema);
+      const RelatedModel = db.model('Test1', RelatedSchema);
 
       RelatedModel.create({ name: 'test' }, function(error, doc) {
         assert.ifError(error);
@@ -5720,7 +5720,7 @@ describe('document', function() {
     it('Using set as a schema path (gh-1939)', function(done) {
       const testSchema = new Schema({ set: String });
 
-      const Test = db.model('gh1939', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const t = new Test({ set: 'test 1' });
       assert.equal(t.set, 'test 1');
@@ -5743,7 +5743,7 @@ describe('document', function() {
         }
       });
 
-      const Test = db.model('gh5780', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const t = new Test({});
       assert.deepEqual(t.toObject().nestedArr, [[0, 1]]);
@@ -5764,7 +5764,7 @@ describe('document', function() {
         }
       });
 
-      const Test = db.model('gh6477_2', schema);
+      const Test = db.model('Test', schema);
 
       const test = new Test;
       assert.strictEqual(test.s, '');
@@ -5798,7 +5798,7 @@ describe('document', function() {
         }
       });
 
-      const Test = db.model('gh6477', schema);
+      const Test = db.model('Test', schema);
 
       return co(function* () {
         // use native driver directly to kill the fields
@@ -5837,7 +5837,7 @@ describe('document', function() {
         return this.get('children.0');
       });
 
-      const Person = db.model('gh6223', personSchema);
+      const Person = db.model('Person', personSchema);
 
       const person = new Person({
         name: 'Anakin'
@@ -5855,7 +5855,7 @@ describe('document', function() {
 
       testSchema.virtual('totalValue');
 
-      const Test = db.model('gh6262', testSchema);
+      const Test = db.model('Test', testSchema);
 
       assert.equal(Test.schema.virtuals.totalValue.getters.length, 1);
       assert.equal(Test.schema.virtuals.totalValue.setters.length, 1);
@@ -5880,7 +5880,7 @@ describe('document', function() {
         virtuals: true
       });
 
-      const MyModel = db.model('gh6294', schema);
+      const MyModel = db.model('Test', schema);
 
       const doc = new MyModel({ nested: { prop: 'test 1' } });
 
@@ -5916,17 +5916,17 @@ describe('document', function() {
       const blogPostSchema = new Schema({
         comments: [{
           type: mongoose.Schema.Types.ObjectId,
-          ref: 'gh6048_0'
+          ref: 'Comment'
         }]
       });
 
-      const BlogPost = db.model('gh6048', blogPostSchema);
+      const BlogPost = db.model('BlogPost', blogPostSchema);
 
       const commentSchema = new Schema({
         text: String
       });
 
-      const Comment = db.model('gh6048_0', commentSchema);
+      const Comment = db.model('Comment', commentSchema);
 
       return co(function*() {
         let blogPost = yield BlogPost.create({});
@@ -6024,13 +6024,13 @@ describe('document', function() {
           }
         }
       });
-      const Child = mongoose.model('Child', childSchema);
+      const Child = db.model('Child', childSchema);
 
       const parentSchema = new Schema({
         name: String,
         child: childSchema
       });
-      const Parent = mongoose.model('Parent', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const child = new Child(/* name is required */);
       const parent = new Parent({ child: child });
@@ -7595,7 +7595,7 @@ describe('document', function() {
       type: String,
     }, opts);
 
-    const IssueModel = mongoose.model('Test', IssueSchema);
+    const IssueModel = db.model('Test', IssueSchema);
 
     const SubIssueSchema = new mongoose.Schema({
       checklist: [{
@@ -7785,7 +7785,7 @@ describe('document', function() {
   describe('overwrite() (gh-7830)', function() {
     let Model;
 
-    before(function() {
+    beforeEach(function() {
       const schema = new Schema({
         _id: Number,
         name: String,
@@ -7798,7 +7798,7 @@ describe('document', function() {
           immutable: true
         }
       });
-      Model = db.model('gh7830', schema);
+      Model = db.model('Test', schema);
     });
 
     it('works', function() {
@@ -7860,8 +7860,8 @@ describe('document', function() {
       parents: [ParentSchema]
     }, { _id: false, id: false });
 
-    const Parent = db.model('gh7898_Parent', ParentSchema);
-    const Wrapper = db.model('gh7898_Wrapper', WrapperSchema);
+    const Parent = db.model('Parent', ParentSchema);
+    const Wrapper = db.model('Test', WrapperSchema);
 
     const data = { name: 'P1', children: [{ name: 'C1' }, { name: 'C2' }] };
     const parent = new Parent(data);
@@ -7874,7 +7874,7 @@ describe('document', function() {
   describe('immutable properties (gh-7671)', function() {
     let Model;
 
-    before(function() {
+    beforeEach(function() {
       const schema = new Schema({
         createdAt: {
           type: Date,
@@ -7883,7 +7883,7 @@ describe('document', function() {
         },
         name: String
       });
-      Model = db.model('gh7671', schema);
+      Model = db.model('Test', schema);
     });
 
     it('SchemaType#immutable()', function() {
@@ -7954,7 +7954,7 @@ describe('document', function() {
           immutable: doc => doc.name === 'foo'
         }
       });
-      const Model = db.model('gh8001', schema);
+      const Model = db.model('Test1', schema);
 
       return co(function*() {
         const doc1 = yield Model.create({ name: 'foo', test: 'before' });
@@ -7978,7 +7978,7 @@ describe('document', function() {
           name: String,
           yearOfBirth: { type: Number, immutable: true }
         }, { strict: 'throw' });
-        const Person = db.model('gh8149', schema);
+        const Person = db.model('Person', schema);
         const joe = yield Person.create({ name: 'Joe', yearOfBirth: 2001 });
 
         joe.set({ yearOfBirth: 2002 });
@@ -7999,7 +7999,7 @@ describe('document', function() {
     Child.pre('save', () => calls.push(2));
     Parent.pre('save', () => calls.push(3));
 
-    const Model = db.model('gh7929', Parent);
+    const Model = db.model('Parent', Parent);
 
     return Model.create({ children: [{ children: [{ value: 3 }] }] }).then(() => {
       assert.deepEqual(calls, [1, 2, 3]);
@@ -8017,7 +8017,7 @@ describe('document', function() {
       }
     }, { toObject : { getters: true } });
 
-    const Model = db.model('gh7940', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.create({ foo: 'test', bar: 'baz' });
@@ -8030,7 +8030,7 @@ describe('document', function() {
 
   it('loads doc with a `once` property successfully (gh-7958)', function() {
     const eventSchema = Schema({ once: { prop: String } });
-    const Event = db.model('gh7958', eventSchema);
+    const Event = db.model('Test', eventSchema);
 
     return co(function*() {
       yield Event.create({ once: { prop: 'test' } });
@@ -8049,7 +8049,7 @@ describe('document', function() {
         }
       });
 
-      const MyModel = db.model('gh8150', mySchema);
+      const MyModel = db.model('Test', mySchema);
 
       yield MyModel.create({ id: 12345 });
 
@@ -8060,7 +8060,7 @@ describe('document', function() {
 
   it('handles objectids and decimals with strict: false (gh-7973)', function() {
     const testSchema = Schema({}, { strict: false });
-    const Test = db.model('gh7973', testSchema);
+    const Test = db.model('Test', testSchema);
 
     let doc = new Test({
       testId: new mongoose.Types.ObjectId(),
@@ -8087,7 +8087,7 @@ describe('document', function() {
       }
     });
 
-    const Model = db.model('gh7926', schema);
+    const Model = db.model('Test', schema);
 
     return Model.create({ test: [['foo']] }).then(() => assert.ok(false), err => {
       assert.ok(err);
@@ -8102,13 +8102,13 @@ describe('document', function() {
     const schema2 = Schema({
       keyToPopulate: {
         type: mongoose.Schema.Types.ObjectId,
-        ref: 'gh8018_child',
+        ref: 'Child',
         required: true
       }
     });
 
-    const Child = db.model('gh8018_child', schema);
-    const Parent = db.model('gh8018_parent', schema2);
+    const Child = db.model('Child', schema);
+    const Parent = db.model('Parent', schema2);
 
     return co(function*() {
       const child = yield Child.create({ test: 'test' });
@@ -8144,7 +8144,7 @@ describe('document', function() {
     const schema = new Schema({
       items: [itemArray]
     });
-    const Model = db.model('gh8067', schema);
+    const Model = db.model('Test', schema);
 
     const obj = new Model({
       items: [
@@ -8158,7 +8158,7 @@ describe('document', function() {
 
   it('only calls validator once on nested mixed validator (gh-8117)', function() {
     const called = [];
-    const Model = db.model('gh8117', Schema({
+    const Model = db.model('Test', Schema({
       name: { type: String },
       level1: {
         level2: {
@@ -8193,9 +8193,9 @@ describe('document', function() {
 
     mongoose.Schema.Types.Gh8062 = Gh8062;
 
-    const schema = new Schema({ arr: [{ type: Gh8062, ref: 'gh8062_child' }] });
-    const Model = db.model('gh8062', schema);
-    const Child = db.model('gh8062_child', Schema({ _id: Gh8062 }));
+    const schema = new Schema({ arr: [{ type: Gh8062, ref: 'Child' }] });
+    const Model = db.model('Test', schema);
+    const Child = db.model('Child', Schema({ _id: Gh8062 }));
 
     return co(function*() {
       yield Child.create({ _id: 'test' });
@@ -8211,7 +8211,7 @@ describe('document', function() {
   it('can inspect() on a document array (gh-8037)', function() {
     const subdocSchema = mongoose.Schema({ a: String });
     const schema = mongoose.Schema({ subdocs: { type: [subdocSchema] } });
-    const Model = db.model('gh8037', schema);
+    const Model = db.model('Test', schema);
     const data = { _id: new mongoose.Types.ObjectId(), subdocs: [{a: 'a'}] };
     const doc = new Model();
     doc.init(data);
@@ -8227,7 +8227,7 @@ describe('document', function() {
       name: { type: String, required: true },
       address: { type: AddressSchema, required: true }
     });
-    const Person = db.model('gh8201', PersonSchema);
+    const Person = db.model('Person', PersonSchema);
 
     return co(function*() {
       yield Person.create({
@@ -8253,7 +8253,7 @@ describe('document', function() {
   it('setting single nested subdoc with timestamps (gh-8251)', function() {
     const ActivitySchema = Schema({ description: String }, { timestamps: true });
     const RequestSchema = Schema({ activity: ActivitySchema });
-    const Request = db.model('gh8251', RequestSchema);
+    const Request = db.model('Test', RequestSchema);
 
     return co(function*() {
       const doc = yield Request.create({
@@ -8270,7 +8270,7 @@ describe('document', function() {
   it('passing an object with toBSON() into `save()` (gh-8299)', function() {
     const ActivitySchema = Schema({ description: String });
     const RequestSchema = Schema({ activity: ActivitySchema });
-    const Request = db.model('gh8299', RequestSchema);
+    const Request = db.model('Test', RequestSchema);
 
     return co(function*() {
       const doc = yield Request.create({
@@ -8289,12 +8289,12 @@ describe('document', function() {
     childSchema.virtual('field').
       get(function() { return this._field; }).
       set(function(v) { return this._field = v; });
-    const Child = db.model('gh8295_Child', childSchema);
+    const Child = db.model('Child', childSchema);
 
     const parentSchema = Schema({
-      child: { type: mongoose.ObjectId, ref: 'gh8295_Child', get: get }
+      child: { type: mongoose.ObjectId, ref: 'Child', get: get }
     }, { toJSON: { getters: true } });
-    const Parent = db.model('gh8295_Parent', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     function get(child) {
       child.field = true;
@@ -8315,7 +8315,7 @@ describe('document', function() {
         enum: [1, 2, 3]
       }
     });
-    const Model = db.model('gh8139', schema);
+    const Model = db.model('Test', schema);
 
     let doc = new Model({});
     let err = doc.validateSync();
@@ -8343,7 +8343,7 @@ describe('document', function() {
       },
       rank: String
     });
-    const Model = db.model('gh7587_0', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc = new Model({});
@@ -8360,7 +8360,7 @@ describe('document', function() {
     const schema = Schema({
       nums: [Number]
     });
-    const Model = db.model('gh4322', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc = yield Model.create({ nums: [3, 4] });
@@ -8396,7 +8396,7 @@ describe('document', function() {
         name: String
       })
     });
-    const Model = db.model('gh8400', schema);
+    const Model = db.model('Test', schema);
 
     const doc1 = new Model({ name: 'doc1', subdoc: { name: 'subdoc1' } });
     const doc2 = new Model({ name: 'doc2', subdoc: { name: 'subdoc2' } });
@@ -8409,12 +8409,12 @@ describe('document', function() {
   });
 
   it('setting an array to an array with some populated documents depopulates the whole array (gh-8443)', function() {
-    const A = db.model('gh8443_A', Schema({
+    const A = db.model('Test1', Schema({
       name: String,
-      rel: [{ type: mongoose.ObjectId, ref: 'gh8443_B' }]
+      rel: [{ type: mongoose.ObjectId, ref: 'Test' }]
     }));
 
-    const B = db.model('gh8443_B', Schema({ name: String }));
+    const B = db.model('Test', Schema({ name: String }));
 
     return co(function*() {
       const b = yield B.create({ name: 'testb' });
@@ -8444,7 +8444,7 @@ describe('document', function() {
     });
 
     const fatherSchema = Schema({ children: [childSchema] });
-    const Father = db.model('gh8466', fatherSchema);
+    const Father = db.model('Test', fatherSchema);
 
     const doc = new Father({
       children: [{ name: 'Valid' }, { name: 'Invalid' }]
@@ -8458,7 +8458,7 @@ describe('document', function() {
   });
 
   it('throws an error if running validate() multiple times in parallel (gh-8468)', () => {
-    const Model = db.model('gh8468', Schema({ name: String }));
+    const Model = db.model('Test', Schema({ name: String }));
 
     const doc = new Model({ name: 'test' });
 
@@ -8479,7 +8479,7 @@ describe('document', function() {
         })
       }
     });
-    const Test = db.model('gh8486', testSchema);
+    const Test = db.model('Test', testSchema);
 
     return co(function*() {
       const doc = yield Test.create({});

From 600801b193de900cc7fa3f9d34db88e8a6106203 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 13:25:44 -0500
Subject: [PATCH 0405/2348] test: clean up unnecessary unique index re: #8481

---
 test/document.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 5f3be231136..a9fa2c81c27 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -4128,7 +4128,6 @@ describe('document', function() {
         },
         email: {
           type: String,
-          unique: true,
           lowercase: true,
           required: true
         },

From 1d5e9dae47451c6e8702c6711fc10c568c7217fd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 13:41:53 -0500
Subject: [PATCH 0406/2348] test(document): repro #8509

---
 test/document.test.js | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index a9fa2c81c27..b57f85ff6f4 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8516,4 +8516,41 @@ describe('document', function() {
     assert.ok(err.errors['startDate']);
     assert.equal(err.errors['startDate'].message, 'test');
   });
+
+  it('sets parent and ownerDocument correctly with document array default (gh-8509)', function() {
+    const locationSchema = Schema({
+      name: String,
+      city: String
+    });
+    const owners = [];
+      
+    // Middleware to set a default location name derived from the parent organization doc
+    locationSchema.pre('validate', function(next) {
+      const owner = this.ownerDocument();
+      owners.push(owner);
+      if (this.isNew && !this.get('name') && owner.get('name')) {
+        this.set('name', `${owner.get('name')} Office`);
+      }
+      next();
+    }); 
+
+    const organizationSchema = Schema({
+      name: String,
+      // Having a default doc this way causes issues
+      locations: { type: [locationSchema], default: [{}] }
+    });
+    const Organization = db.model('Test', organizationSchema);
+
+    return co(function*() {
+      const org = new Organization();
+      org.set('name', 'MongoDB');
+
+      yield org.save();
+
+      assert.equal(owners.length, 1);
+      assert.ok(owners[0] === org);
+
+      assert.equal(org.locations[0].name, 'MongoDB Office');
+    });
+  });
 });

From e8dd4af1b7e0f69ec2c8a617540282fd29fbf6cd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 13:52:04 -0500
Subject: [PATCH 0407/2348] fix(document): ensure parent and ownerDocument are
 set for subdocs in document array defaults

Fix #8509
---
 lib/schema/documentarray.js | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 06c6a0b5e74..f892af0bac5 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -331,16 +331,21 @@ DocumentArrayPath.prototype.getDefault = function(scope) {
   }
 
   ret = new MongooseDocumentArray(ret, this.path, scope);
-  const _parent = ret[arrayParentSymbol];
-  ret[arrayParentSymbol] = null;
 
   for (let i = 0; i < ret.length; ++i) {
     const Constructor = getConstructor(this.casterConstructor, ret[i]);
-    ret[i] = new Constructor(ret[i], ret, undefined,
+    const _subdoc = new Constructor({}, ret, undefined,
       undefined, i);
-  }
+    _subdoc.init(ret[i]);
+    _subdoc.isNew = true;
+
+    // Make sure all paths in the subdoc are set to `default` instead
+    // of `init` since we used `init`.
+    Object.assign(_subdoc.$__.activePaths.default, _subdoc.$__.activePaths.init);
+    _subdoc.$__.activePaths.init = {};
 
-  ret[arrayParentSymbol] = _parent;
+    ret[i] = _subdoc;
+  }
 
   return ret;
 };

From 7de0c44083c4831e65535d5aac663c5a7ead8a8c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 14:36:24 -0500
Subject: [PATCH 0408/2348] style: fix lint

---
 lib/schema/documentarray.js | 1 -
 test/document.test.js       | 4 ++--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index f892af0bac5..c8e72aaf20c 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -18,7 +18,6 @@ const util = require('util');
 const utils = require('../utils');
 const getConstructor = require('../helpers/discriminator/getConstructor');
 
-const arrayParentSymbol = require('../helpers/symbols').arrayParentSymbol;
 const arrayPathSymbol = require('../helpers/symbols').arrayPathSymbol;
 const documentArrayParent = require('../helpers/symbols').documentArrayParent;
 
diff --git a/test/document.test.js b/test/document.test.js
index b57f85ff6f4..0a7a6afe6f9 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8523,7 +8523,7 @@ describe('document', function() {
       city: String
     });
     const owners = [];
-      
+
     // Middleware to set a default location name derived from the parent organization doc
     locationSchema.pre('validate', function(next) {
       const owner = this.ownerDocument();
@@ -8532,7 +8532,7 @@ describe('document', function() {
         this.set('name', `${owner.get('name')} Office`);
       }
       next();
-    }); 
+    });
 
     const organizationSchema = Schema({
       name: String,

From 1af5f58955101291b618b3e67b2a0fc1e3c3ac3d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Jan 2020 15:03:57 -0500
Subject: [PATCH 0409/2348] fix(document): dont set undefined keys to null if
 minimize is false

Fix #8504
---
 lib/utils.js          |  8 ++++++--
 test/document.test.js | 27 +++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/lib/utils.js b/lib/utils.js
index 33a77fb4b67..1412dcd8980 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -333,8 +333,12 @@ function cloneObject(obj, options, isArrayChild) {
     const val = clone(obj[k], options);
 
     if (!minimize || (typeof val !== 'undefined')) {
-      hasKeys || (hasKeys = true);
-      ret[k] = val;
+      if (minimize === false && typeof val === 'undefined') {
+        delete ret[k];
+      } else {
+        hasKeys || (hasKeys = true);
+        ret[k] = val;
+      }
     }
   }
 
diff --git a/test/document.test.js b/test/document.test.js
index 0a7a6afe6f9..2bf27f231e8 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8553,4 +8553,31 @@ describe('document', function() {
       assert.equal(org.locations[0].name, 'MongoDB Office');
     });
   });
+
+  it('doesnt add `null` if property is undefined with minimize false (gh-8504)', function() {
+    const minimize = false;
+    const schema = Schema({
+      num: Number,
+      beta: { type: String }
+    },
+    {
+      toObject: { virtuals: true, minimize: minimize },
+      toJSON: { virtuals: true, minimize: minimize }
+    }
+    );
+    const Test = db.model('Test', schema);
+
+    const dummy1 = new Test({ num: 1, beta: null });
+    const dummy2 = new Test({ num: 2, beta: void 0 });
+
+    return co(function*() {
+      yield dummy1.save();
+      yield dummy2.save();
+
+      const res = yield Test.find().lean().sort({ num: 1 });
+
+      assert.strictEqual(res[0].beta, null);
+      assert.ok(!res[1].hasOwnProperty('beta'));
+    });
+  });
 });

From 21663048ed73d69c2a35574e1b7b75de954a269b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 22 Jan 2020 09:29:21 -0500
Subject: [PATCH 0410/2348] docs(model): document `insertMany` `lean` option

Fix #8522
---
 lib/model.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/model.js b/lib/model.js
index 87177db419b..bc1ec6a98b7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3217,6 +3217,7 @@ Model.startSession = function() {
  * @param {Object} [options] see the [mongodb driver options](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#insertMany)
  * @param {Boolean} [options.ordered = true] if true, will fail fast on the first error encountered. If false, will insert all the documents it can and report errors later. An `insertMany()` with `ordered = false` is called an "unordered" `insertMany()`.
  * @param {Boolean} [options.rawResult = false] if false, the returned promise resolves to the documents that passed mongoose document validation. If `true`, will return the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~insertWriteOpCallback) with a `mongoose` property that contains `validationErrors` if this is an unordered `insertMany`.
+ * @param {Boolean} [options.lean = false] if `true`, skips hydrating and validating the documents. This option is useful if you need the extra performance, but Mongoose won't validate the documents before inserting.
  * @param {Function} [callback] callback
  * @return {Promise}
  * @api public

From d8adc154b3fcef334df644efac5fb190893582cc Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Thu, 23 Jan 2020 17:58:10 -0700
Subject: [PATCH 0411/2348] test and Fixes #8531 - only call validate once for
 subdocuments

---
 lib/document.js       | 35 +++++++++++++++++------------------
 test/document.test.js | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 18 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0444fd3b18c..904916f9217 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2097,24 +2097,22 @@ function _getPathsToValidate(doc) {
   paths = paths.concat(Object.keys(doc.$__.activePaths.states.modify));
   paths = paths.concat(Object.keys(doc.$__.activePaths.states.default));
 
-  if (!doc.ownerDocument) {
-    const subdocs = doc.$__getAllSubdocs();
-    let subdoc;
-    len = subdocs.length;
-    const modifiedPaths = doc.modifiedPaths();
-    for (i = 0; i < len; ++i) {
-      subdoc = subdocs[i];
-      if (doc.isModified(subdoc.$basePath, modifiedPaths) &&
-          !doc.isDirectModified(subdoc.$basePath) &&
-          !doc.$isDefault(subdoc.$basePath)) {
-        // Remove child paths for now, because we'll be validating the whole
-        // subdoc
-        paths = paths.filter(function(p) {
-          return p != null && p.indexOf(subdoc.$basePath + '.') !== 0;
-        });
-        paths.push(subdoc.$basePath);
-        skipSchemaValidators[subdoc.$basePath] = true;
-      }
+  const subdocs = doc.$__getAllSubdocs();
+  let subdoc;
+  len = subdocs.length;
+  const modifiedPaths = doc.modifiedPaths();
+  for (i = 0; i < len; ++i) {
+    subdoc = subdocs[i];
+    if (doc.isModified(subdoc.$basePath, modifiedPaths) &&
+        !doc.isDirectModified(subdoc.$basePath) &&
+        !doc.$isDefault(subdoc.$basePath)) {
+      // Remove child paths for now, because we'll be validating the whole
+      // subdoc
+      paths = paths.filter(function(p) {
+        return p != null && p.indexOf(subdoc.$basePath + '.') !== 0;
+      });
+      paths.push(subdoc.$basePath); // This can cause duplicates, make unique below
+      skipSchemaValidators[subdoc.$basePath] = true;
     }
   }
 
@@ -2187,6 +2185,7 @@ function _getPathsToValidate(doc) {
     }
   }
 
+  paths = Array.from(new Set(paths));
   return [paths, skipSchemaValidators];
 }
 
diff --git a/test/document.test.js b/test/document.test.js
index 2bf27f231e8..7acad6d6bf6 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -569,6 +569,47 @@ describe('document', function() {
     assert.equal(obj.answer, 42);
   });
 
+  it('can save multiple times with changes to complex subdocuments (gh-8531)', () => {
+    const clipSchema = Schema({
+      height: Number,
+      rows: Number,
+      width: Number,
+    }, {_id: false, id: false});
+    const questionSchema = Schema({
+      type: String,
+      age: Number,
+      clip: {
+        type: clipSchema,
+      },
+    }, {_id: false, id: false});
+    const keySchema = Schema({ql: [questionSchema]}, {_id: false, id: false});
+    const Model = db.model('gh8468-2', Schema({
+      name: String,
+      keys: [keySchema],
+    }));
+    const doc = new Model({
+      name: 'test',
+      keys: [
+        {ql: [
+          { type: 'mc', clip: {width: 1} },
+          { type: 'mc', clip: {height: 1, rows: 1} },
+          { type: 'mc', clip: {height: 2, rows: 1} },
+          { type: 'mc', clip: {height: 3, rows: 1} },
+        ]},
+      ],
+    });
+    return doc.save().then(() => {
+      // The following was failing before fixing gh-8531 because
+      // the validation was called for the "clip" document twice in the
+      // same stack, causing a "can't validate() the same doc multiple times in
+      // parallel" warning
+      doc.keys[0].ql[0].clip = {width: 4.3, rows: 3};
+      doc.keys[0].ql[0].age = 42;
+
+      return doc.save();
+    }); // passes
+  });
+
   it('saves even if `_id` is null (gh-6406)', function() {
     const schema = new Schema({ _id: Number, val: String });
     const Model = db.model('Test', schema);

From 9249cfb531c189646047e8167674b109b7f82084 Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Thu, 23 Jan 2020 18:40:19 -0700
Subject: [PATCH 0412/2348] Fix unit tests which broke with my fix for #8531

---
 lib/document.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 904916f9217..b0594124d4d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2103,7 +2103,8 @@ function _getPathsToValidate(doc) {
   const modifiedPaths = doc.modifiedPaths();
   for (i = 0; i < len; ++i) {
     subdoc = subdocs[i];
-    if (doc.isModified(subdoc.$basePath, modifiedPaths) &&
+    if (subdoc.$basePath &&
+        doc.isModified(subdoc.$basePath, modifiedPaths) &&
         !doc.isDirectModified(subdoc.$basePath) &&
         !doc.$isDefault(subdoc.$basePath)) {
       // Remove child paths for now, because we'll be validating the whole

From 9a9ca0805e4524a0e0c061d43bbff1095b3bb641 Mon Sep 17 00:00:00 2001
From: ian <ian@atlassian.com>
Date: Tue, 21 Jan 2020 22:38:32 -0500
Subject: [PATCH 0413/2348] Improve performance of document creation.

The most common case for _pathToPositionalSyntax is that there's no
positional syntax present. By avoiding the two calls to Regexp.replace,
we can avoid creating two additional copies of the given path string per
call. During document creation this function is called very frequently.

By avoiding extraneous calls to string split, we can reduce the number
of string copies performed and garbage generated as a result.
---
 benchmarks/create.js | 5 +++--
 lib/document.js      | 4 ++--
 lib/schema.js        | 5 ++++-
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/benchmarks/create.js b/benchmarks/create.js
index beb6bf148aa..ccccdd95daf 100644
--- a/benchmarks/create.js
+++ b/benchmarks/create.js
@@ -30,8 +30,9 @@ const doc = JSON.parse(fs.readFileSync(__dirname + '/bigboard.json'));
 // console.error('reading from disk and parsing JSON took %d ms', time1);
 
 const start2 = new Date();
-for (let i = 0; i < 1000; ++i) {
+const iterations = 1000;
+for (let i = 0; i < iterations; ++i) {
   new Board(doc);
 }
 const time2 = (new Date - start2);
-console.error('creation of large object took %d ms', time2);
+console.error('creation of large object took %d ms, %d ms per object', time2, time2 / iterations);
diff --git a/lib/document.js b/lib/document.js
index 0444fd3b18c..7ba08cef531 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -306,7 +306,7 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
     }
 
     const type = doc.schema.paths[p];
-    const path = p.split('.');
+    const path = p.indexOf('.') === -1 ? [p] : p.split('.');
     const len = path.length;
     let included = false;
     let doc_ = doc._doc;
@@ -982,7 +982,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
   }
 
   let schema;
-  const parts = path.split('.');
+  const parts = path.indexOf('.') === -1 ? [path] : path.split('.');
 
   // Might need to change path for top-level alias
   if (typeof this.schema.aliases[parts[0]] == 'string') {
diff --git a/lib/schema.js b/lib/schema.js
index 82d557659c5..06cd1d4341b 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -817,6 +817,9 @@ function _getPath(schema, path, cleanPath) {
  */
 
 function _pathToPositionalSyntax(path) {
+  if (!/\.\d+/.test(path)) {
+    return path;
+  }
   return path.replace(/\.\d+\./g, '.$.').replace(/\.\d+$/, '.$');
 }
 
@@ -1084,7 +1087,7 @@ Schema.prototype.indexedPaths = function indexedPaths() {
 
 Schema.prototype.pathType = function(path) {
   // Convert to '.$' to check subpaths re: gh-6405
-  const cleanPath = path.replace(/\.\d+\./g, '.$.').replace(/\.\d+$/, '.$');
+  const cleanPath = _pathToPositionalSyntax(path);
 
   if (this.paths.hasOwnProperty(path)) {
     return 'real';

From 3bbddefa9b8e5ade1b430094257356f8a3949279 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Fri, 24 Jan 2020 17:22:30 -0600
Subject: [PATCH 0414/2348] Copy plugins from base schema when creating a
 discriminator

---
 lib/helpers/model/discriminator.js |  2 +-
 test/model.discriminator.test.js   | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index 9c58627775d..ef0a880f1b1 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -158,7 +158,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     schema.options.id = id;
     schema.s.hooks = model.schema.s.hooks.merge(schema.s.hooks);
 
-    schema.plugins = Array.prototype.slice(baseSchema.plugins);
+    schema.plugins = Array.prototype.slice.call(baseSchema.plugins);
     schema.callQueue = baseSchema.callQueue.concat(schema.callQueue);
     delete schema._requiredpaths; // reset just in case Schema#requiredPaths() was called on either schema
   }
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 429c5c18620..027f3d76c20 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1309,6 +1309,19 @@ describe('model', function() {
         });
       });
     });
+
+    it.only('should copy plugins', function () {
+      const plugin = (schema) => { };
+
+      const schema = new Schema({ value: String });
+      schema.plugin(plugin)
+      const model = mongoose.model('Model', schema);
+
+      const discriminator = model.discriminator('Desc', new Schema({ anotherValue: String }));
+
+      const copiedPlugin = discriminator.schema.plugins.find(p => p.fn === plugin);
+      assert.ok(!!copiedPlugin);
+    });
   });
 
   describe('bug fixes', function() {

From b654ddd1bb34aae2168e414db4b4c4b131b44e54 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Fri, 24 Jan 2020 17:43:00 -0600
Subject: [PATCH 0415/2348] Fix test issue

---
 test/model.discriminator.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 027f3d76c20..388aa1a6e32 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1310,7 +1310,7 @@ describe('model', function() {
       });
     });
 
-    it.only('should copy plugins', function () {
+    it('should copy plugins', function () {
       const plugin = (schema) => { };
 
       const schema = new Schema({ value: String });

From efea74237292c4771e60dfe098e3366a1440aef8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 24 Jan 2020 20:16:20 -0500
Subject: [PATCH 0416/2348] test(model): repro #8521

---
 test/model.indexes.test.js | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 94255a54ef3..dfa45f582ef 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -480,6 +480,43 @@ describe('model', function() {
         then(dropped => assert.equal(dropped.length, 0));
     });
 
+    it('different collation with syncIndexes() (gh-8521)', function() {
+      return co(function*() {
+        yield db.db.collection('users').drop().catch(() => {});
+
+        let userSchema = new mongoose.Schema({ username: String });
+        userSchema.index({ username: 1 }, { unique: true });
+        let User = db.model('User', userSchema);
+
+        yield User.init();
+        let indexes = yield User.listIndexes();
+        assert.equal(indexes.length, 2);
+        assert.deepEqual(indexes[1].key, { username: 1 });
+        assert.ok(!indexes[1].collation);
+
+        userSchema = new mongoose.Schema({ username: String });
+        userSchema.index({ username: 1 }, {
+          unique: true,
+          collation: {
+            locale: 'en',
+            strength: 2
+          }
+        });
+        db.deleteModel('User');
+        User = db.model('User', userSchema);
+
+        yield User.init();
+        yield User.syncIndexes();
+
+        indexes = yield User.listIndexes();
+        assert.equal(indexes.length, 2);
+        assert.deepEqual(indexes[1].key, { username: 1 });
+        assert.ok(!!indexes[1].collation);
+
+        yield User.collection.drop();
+      });
+    });
+
     it('cleanIndexes (gh-6676)', function() {
       return co(function*() {
         let M = db.model('gh6676', new Schema({

From 0c73d14692306e04ec9d380923af6923a695dd15 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 24 Jan 2020 20:18:45 -0500
Subject: [PATCH 0417/2348] fix(model): ensure `cleanIndexes()` drops indexes
 with different collations

Fix #8521
---
 lib/model.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index bc1ec6a98b7..08d41b72253 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1437,7 +1437,13 @@ function isIndexEqual(model, schemaIndex, dbIndex) {
     utils.clone(schemaIndex[1]));
 
   // If these options are different, need to rebuild the index
-  const optionKeys = ['unique', 'partialFilterExpression', 'sparse', 'expireAfterSeconds'];
+  const optionKeys = [
+    'unique',
+    'partialFilterExpression',
+    'sparse',
+    'expireAfterSeconds',
+    'collation'
+  ];
   for (const key of optionKeys) {
     if (!(key in options) && !(key in dbIndex)) {
       continue;

From 7ca2222a588cd74c5a74a561b2160159c231e6bd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 10:38:41 -0500
Subject: [PATCH 0418/2348] test(update): repro #8524

---
 test/schema.timestamps.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index 60cc3630456..6b1604cb35b 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -356,6 +356,18 @@ describe('schema options.timestamps', function() {
       });
     });
 
+    it('with update pipeline (gh-8524)', function() {
+      return co(function*() {
+        const cat = yield Cat.create({ name: 'Entei' });
+        const updatedAt = cat.updatedAt;
+
+        yield new Promise(resolve => setTimeout(resolve), 50);
+        const updated = yield Cat.findOneAndUpdate({ _id: cat._id },
+          [{ $set: { name: 'Raikou' } }], { new: true });
+        assert.ok(updated.updatedAt.getTime() > updatedAt.getTime());
+      });
+    });
+
     after(function() {
       return Cat.deleteMany({});
     });

From 8b344cfb207495ceca098974d791c7274788afb7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 10:38:54 -0500
Subject: [PATCH 0419/2348] fix(update): bump timestamps when using update
 aggregation pipelines

Re: #8524
---
 lib/helpers/update/applyTimestampsToUpdate.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/helpers/update/applyTimestampsToUpdate.js b/lib/helpers/update/applyTimestampsToUpdate.js
index bd1d864291a..7318232b38b 100644
--- a/lib/helpers/update/applyTimestampsToUpdate.js
+++ b/lib/helpers/update/applyTimestampsToUpdate.js
@@ -42,6 +42,13 @@ function applyTimestampsToUpdate(now, createdAt, updatedAt, currentUpdate, optio
   }
   currentUpdate = currentUpdate || {};
 
+  if (Array.isArray(updates)) {
+    // Update with aggregation pipeline
+    updates.push({ $set: { updatedAt: now } });
+
+    return updates;
+  }
+
   updates.$set = updates.$set || {};
   if (!skipUpdatedAt && updatedAt &&
       (!currentUpdate.$currentDate || !currentUpdate.$currentDate[updatedAt])) {

From b26e1e059ff6cae8dc44d8273f491452931bafc4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 11:06:51 -0500
Subject: [PATCH 0420/2348] test: skip #8524 test if not mongodb 4.2

---
 test/model.update.test.js      | 14 ++++++++++++++
 test/schema.timestamps.test.js | 12 ------------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 7c915227943..9d27f4ebe5c 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3433,5 +3433,19 @@ describe('model: updateOne: ', function() {
         assert.strictEqual(doc.newProp, void 0);
       });
     });
+
+    it('update pipeline timestamps (gh-8524)', function() {
+      const Cat = db.model('Cat', Schema({ name: String }, { timestamps: true }));
+
+      return co(function*() {
+        const cat = yield Cat.create({ name: 'Entei' });
+        const updatedAt = cat.updatedAt;
+
+        yield new Promise(resolve => setTimeout(resolve), 50);
+        const updated = yield Cat.findOneAndUpdate({ _id: cat._id },
+          [{ $set: { name: 'Raikou' } }], { new: true });
+        assert.ok(updated.updatedAt.getTime() > updatedAt.getTime());
+      });
+    });
   });
 });
\ No newline at end of file
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index 6b1604cb35b..60cc3630456 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -356,18 +356,6 @@ describe('schema options.timestamps', function() {
       });
     });
 
-    it('with update pipeline (gh-8524)', function() {
-      return co(function*() {
-        const cat = yield Cat.create({ name: 'Entei' });
-        const updatedAt = cat.updatedAt;
-
-        yield new Promise(resolve => setTimeout(resolve), 50);
-        const updated = yield Cat.findOneAndUpdate({ _id: cat._id },
-          [{ $set: { name: 'Raikou' } }], { new: true });
-        assert.ok(updated.updatedAt.getTime() > updatedAt.getTime());
-      });
-    });
-
     after(function() {
       return Cat.deleteMany({});
     });

From 255d8bdbca232d029e5b4df81e7c3406cb6406d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 11:27:41 -0500
Subject: [PATCH 0421/2348] fix(embedded): only set parentArr if it is a doc
 array re: #8519

---
 lib/types/embedded.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 13d3f567dc3..585c333381b 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -29,7 +29,7 @@ const validatorErrorSymbol = require('../helpers/symbols').validatorErrorSymbol;
  */
 
 function EmbeddedDocument(obj, parentArr, skipId, fields, index) {
-  if (parentArr) {
+  if (parentArr != null && parentArr.isMongooseDocumentArray) {
     this.__parentArray = parentArr;
     this[documentArrayParent] = parentArr.$parent();
   } else {

From 23f43fca2bf12d3f7bfcc695bdc67826117d6fee Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 11:55:46 -0500
Subject: [PATCH 0422/2348] test(model): reuse collections where possible for
 model.update and model.findOneAndUpdate tests

Re: #8481
---
 test/model.findOneAndUpdate.test.js | 135 +++++++++++++++------------
 test/model.update.test.js           | 136 +++++++---------------------
 2 files changed, 109 insertions(+), 162 deletions(-)

diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 4e5b33675a9..a1a82faed07 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -90,6 +90,21 @@ describe('model: findOneAndUpdate:', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => {
+    const arr = [];
+
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
   it('WWW returns the edited document', function(done) {
     const M = db.model(modelname, collection);
     const title = 'Tobi ' + random();
@@ -768,7 +783,7 @@ describe('model: findOneAndUpdate:', function() {
       title: String
     });
 
-    const B = db.model('gh-1091+1100', postSchema);
+    const B = db.model('BlogPost', postSchema);
     const _id1 = new mongoose.Types.ObjectId;
     const _id2 = new mongoose.Types.ObjectId;
 
@@ -845,7 +860,7 @@ describe('model: findOneAndUpdate:', function() {
       name: { type: String }
     });
 
-    const Fruit = db.model('gh-7734', fruitSchema);
+    const Fruit = db.model('Test', fruitSchema);
     return co(function*() {
       let fruit = yield Fruit.create({ name: 'Apple' });
 
@@ -867,7 +882,7 @@ describe('model: findOneAndUpdate:', function() {
       }
     });
 
-    const Thing = db.model('gh-7770', thingSchema);
+    const Thing = db.model('Test', thingSchema);
     const key = 'some-new-id';
 
     Thing.findOneAndUpdate({_id: key}, {$set: {flag: false}}, {upsert: true, new: false, rawResult:true}).exec(function(err, rawResult) {
@@ -1006,7 +1021,7 @@ describe('model: findOneAndUpdate:', function() {
       name: String
     });
 
-    const Account = db.model('gh5973', accountSchema);
+    const Account = db.model('Test', accountSchema);
 
     const update = { $set: { name: 'test', __v: 1 } };
     return Account.
@@ -1020,7 +1035,7 @@ describe('model: findOneAndUpdate:', function() {
       name: String
     });
 
-    const Account = db.model('gh5973_Update', accountSchema);
+    const Account = db.model('Test', accountSchema);
 
     const update = { $set: { name: 'test', __v: 1 } };
     return Account.
@@ -1033,7 +1048,7 @@ describe('model: findOneAndUpdate:', function() {
     const TickSchema = new Schema({name: String});
     const TestSchema = new Schema({a: Number, b: Number, ticks: [TickSchema]});
 
-    const TestModel = db.model('gh-1932', TestSchema, 'gh-1932');
+    const TestModel = db.model('Test', TestSchema);
 
     TestModel.create({a: 1, b: 0, ticks: [{name: 'eggs'}, {name: 'bacon'}, {name: 'coffee'}]}, function(error) {
       assert.ifError(error);
@@ -1056,7 +1071,7 @@ describe('model: findOneAndUpdate:', function() {
       base: String
     });
 
-    const Breakfast = db.model('gh-2272', s);
+    const Breakfast = db.model('Test', s);
 
     Breakfast.
       findOneAndUpdate({}, {time: undefined, base: undefined}, {}).
@@ -1071,7 +1086,7 @@ describe('model: findOneAndUpdate:', function() {
       base: ObjectId
     });
 
-    const Breakfast = db.model('gh2732', s);
+    const Breakfast = db.model('Test', s);
 
     Breakfast.
       findOneAndUpdate({}, {base: {}}, {}).
@@ -1086,7 +1101,7 @@ describe('model: findOneAndUpdate:', function() {
       test: String
     }, {strict: true});
 
-    const Breakfast = db.model('gh2947', s);
+    const Breakfast = db.model('Test', s);
     const q = Breakfast.findOneAndUpdate({},
       {notInSchema: {a: 1}, test: 'abc'},
       {new: true, strict: true, upsert: true});
@@ -1115,7 +1130,7 @@ describe('model: findOneAndUpdate:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('gh-964', s);
+      const Breakfast = db.model('Test', s);
 
       Breakfast.findOneAndUpdate(
         {},
@@ -1145,7 +1160,7 @@ describe('model: findOneAndUpdate:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('gh-964-2', s);
+      const Breakfast = db.model('Test', s);
 
       Breakfast.
         findOneAndUpdate({}, {base: 'eggs'}, {}).
@@ -1239,7 +1254,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const Profile = db.model('gh7909', profileSchema);
+      const Profile = db.model('Test', profileSchema);
 
       return co(function*() {
         const update = { $setOnInsert: { username: 'test' } };
@@ -1415,7 +1430,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const TestModel = db.model('gh3035', testSchema);
+      const TestModel = db.model('Test', testSchema);
       TestModel.create({id: '1'}, function(error) {
         assert.ifError(error);
         TestModel.findOneAndUpdate({id: '1'}, {$set: {name: 'Joe'}}, {upsert: true, setDefaultsOnInsert: true},
@@ -1433,7 +1448,7 @@ describe('model: findOneAndUpdate:', function() {
         status: String
       });
 
-      const TestModel = db.model('gh3135', testSchema);
+      const TestModel = db.model('Test', testSchema);
       TestModel.create({blob: null, status: 'active'}, function(error) {
         assert.ifError(error);
         TestModel.findOneAndUpdate({id: '1', blob: null}, {$set: {status: 'inactive'}}, {upsert: true, setDefaultsOnInsert: true},
@@ -1457,7 +1472,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const TestModel = db.model('gh3034', testSchema);
+      const TestModel = db.model('Test', testSchema);
       TestModel.create({id: '1'}, function(error) {
         assert.ifError(error);
         TestModel.findOneAndUpdate({id: '1'}, {$set: {name: 'Joe'}}, {upsert: true, setDefaultsOnInsert: true},
@@ -1477,7 +1492,7 @@ describe('model: findOneAndUpdate:', function() {
         b: [Number]
       });
 
-      const TestModel = db.model('gh3107', testSchema);
+      const TestModel = db.model('Test', testSchema);
       const update = { $setOnInsert: { a: [{foo: 'bar'}], b: [2] } };
       const opts = {upsert: true, new: true, setDefaultsOnInsert: true};
       TestModel
@@ -1506,7 +1521,7 @@ describe('model: findOneAndUpdate:', function() {
         records: [recordSchema]
       });
 
-      const Shift = db.model('gh3468', shiftSchema);
+      const Shift = db.model('Test', shiftSchema);
 
       Shift.create({
         userId: 'tom',
@@ -1529,7 +1544,7 @@ describe('model: findOneAndUpdate:', function() {
       const nested = new Schema({num: Number});
       const s = new Schema({nested: nested});
 
-      const MyModel = db.model('gh3580', s);
+      const MyModel = db.model('Test', s);
 
       const update = {nested: {num: 'Not a Number'}};
       MyModel.findOneAndUpdate({}, update, function(error) {
@@ -1542,7 +1557,7 @@ describe('model: findOneAndUpdate:', function() {
       const nested = new Schema({arr: [{num: Number}]});
       const s = new Schema({nested: nested});
 
-      const MyModel = db.model('gh3616', s);
+      const MyModel = db.model('Test', s);
 
       MyModel.create({nested: {arr: [{num: 5}]}}, function(error) {
         assert.ifError(error);
@@ -1559,7 +1574,7 @@ describe('model: findOneAndUpdate:', function() {
     it('setting nested schema (gh-3889)', function(done) {
       const nested = new Schema({ test: String });
       const s = new Schema({ nested: nested });
-      const MyModel = db.model('gh3889', s);
+      const MyModel = db.model('Test', s);
       MyModel.findOneAndUpdate(
         {},
         { $set: { nested: { test: 'abc' } } },
@@ -1576,7 +1591,7 @@ describe('model: findOneAndUpdate:', function() {
         test: String
       });
 
-      const TestModel = db.model('gh4925', testSchema);
+      const TestModel = db.model('Test', testSchema);
       const options = { upsert: true, new: true, rawResult: true };
       const update = { $set: { test: 'abc' } };
 
@@ -1602,7 +1617,7 @@ describe('model: findOneAndUpdate:', function() {
         for: String
       });
 
-      const TestModel = db.model('gh4281', breakfastSchema);
+      const TestModel = db.model('Test', breakfastSchema);
       const options = { upsert: true, new: true };
       const update = { $set: { main: null, for: 'Val' } };
 
@@ -1636,7 +1651,7 @@ describe('model: findOneAndUpdate:', function() {
           }
         }
       });
-      const Board = db.model('gh4305', boardSchema);
+      const Board = db.model('Test', boardSchema);
 
       const update = {
         structure: [
@@ -1677,7 +1692,7 @@ describe('model: findOneAndUpdate:', function() {
         addresses: [AddressSchema]
       });
 
-      const Person = db.model('gh3602', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
 
       const update = { $push: { addresses: { street: 'not a num' } } };
       Person.findOneAndUpdate({}, update, function(error) {
@@ -1693,7 +1708,7 @@ describe('model: findOneAndUpdate:', function() {
         test1: String,
         test2: String
       });
-      const Test = db.model('gh4315', TestSchema);
+      const Test = db.model('Test', TestSchema);
       const update = { $set: { test1: 'a', test2: 'b' } };
       const options = { projection: { test2: 0 }, new: true, upsert: true };
       Test.findOneAndUpdate({}, update, options, function(error, doc) {
@@ -1707,7 +1722,7 @@ describe('model: findOneAndUpdate:', function() {
     it('handles upserting a non-existing field (gh-4757)', function(done) {
       const modelSchema = new Schema({ field: Number }, { strict: 'throw' });
 
-      const Model = db.model('gh4757', modelSchema);
+      const Model = db.model('Test', modelSchema);
       Model.findOneAndUpdate({ nonexistingField: 1 }, { field: 2 }, {
         upsert: true,
         setDefaultsOnInsert: true,
@@ -1722,7 +1737,7 @@ describe('model: findOneAndUpdate:', function() {
     it('strict option (gh-5108)', function(done) {
       const modelSchema = new Schema({ field: Number }, { strict: 'throw' });
 
-      const Model = db.model('gh5108', modelSchema);
+      const Model = db.model('Test', modelSchema);
       Model.findOneAndUpdate({}, { field: 2, otherField: 3 }, {
         upsert: true,
         strict: false,
@@ -1740,7 +1755,7 @@ describe('model: findOneAndUpdate:', function() {
         nested: { field1: Number, field2: Number }
       });
 
-      const Model = db.model('gh6484', modelSchema);
+      const Model = db.model('Test', modelSchema);
       const opts = { upsert: true, new: true };
       return Model.findOneAndUpdate({}, { nested: { field1: 1, field2: 2 } }, opts).exec().
         then(function() {
@@ -1791,7 +1806,7 @@ describe('model: findOneAndUpdate:', function() {
         },
         otherName: String
       });
-      const Test = db.model('gh3556', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const opts = { overwrite: true, runValidators: true };
       Test.findOneAndUpdate({}, { otherName: 'test' }, opts, function(error) {
@@ -1809,7 +1824,7 @@ describe('model: findOneAndUpdate:', function() {
         elems: [String]
       });
 
-      const Model = db.model('gh5628', schema);
+      const Model = db.model('Test', schema);
       Model.create({ elems: ['a', 'b'] }, function(error, doc) {
         assert.ifError(error);
         const query = { _id: doc._id, elems: 'a' };
@@ -1831,7 +1846,7 @@ describe('model: findOneAndUpdate:', function() {
         arr: [{ tag: String }]
       });
 
-      const Model = db.model('gh5661', schema);
+      const Model = db.model('Test', schema);
       const doc = { arr: [{ tag: 't1' }, { tag: 't2' }] };
       Model.create(doc, function(error) {
         assert.ifError(error);
@@ -1857,7 +1872,7 @@ describe('model: findOneAndUpdate:', function() {
         num2: Number
       });
 
-      const Model = db.model('gh5609', schema);
+      const Model = db.model('Test', schema);
 
       const opts = { multipleCastError: true };
       Model.findOneAndUpdate({}, { num1: 'fail', num2: 'fail' }, opts, function(error) {
@@ -1876,7 +1891,7 @@ describe('model: findOneAndUpdate:', function() {
         arr: [String]
       });
 
-      const Model = db.model('gh5710', schema);
+      const Model = db.model('Test', schema);
 
       const update = { $addToSet: { arr: null } };
       const options = { runValidators: true };
@@ -1899,7 +1914,7 @@ describe('model: findOneAndUpdate:', function() {
             }
           }
         });
-        const Model = db.model('gh6203', userSchema);
+        const Model = db.model('Test', userSchema);
 
         yield Model.findOneAndUpdate({ foo: '123' }, { name: 'bar' });
 
@@ -1920,7 +1935,7 @@ describe('model: findOneAndUpdate:', function() {
             }
           }
         });
-        const Model = db.model('gh6203_0', userSchema);
+        const Model = db.model('User', userSchema);
 
         yield Model.findOneAndUpdate({ foo: '123' }, { name: 'bar' }, {
           useFindAndModify: false
@@ -1944,13 +1959,13 @@ describe('model: findOneAndUpdate:', function() {
         arr: [String]
       });
 
-      const Model = m.model('gh5616', schema);
+      const Model = m.model('Test', schema);
 
       const update = { $push: { arr: 'test' } };
       const options = { useFindAndModify: false };
       Model.findOneAndUpdate({}, update, options, function() {
         assert.equal(calls.length, 1);
-        assert.equal(calls[0].collection, 'gh5616');
+        assert.equal(calls[0].collection, 'tests');
         assert.equal(calls[0].fnName, 'findOneAndUpdate');
         m.disconnect();
         done();
@@ -1972,13 +1987,13 @@ describe('model: findOneAndUpdate:', function() {
         arr: [String]
       });
 
-      const Model = m.model('gh5616', schema);
+      const Model = m.model('Test', schema);
 
       const update = { $push: { arr: 'test' } };
       const options = {};
       Model.findOneAndUpdate({}, update, options, function() {
         assert.equal(calls.length, 1);
-        assert.equal(calls[0].collection, 'gh5616');
+        assert.equal(calls[0].collection, 'tests');
         assert.equal(calls[0].fnName, 'findOneAndUpdate');
         m.disconnect();
         done();
@@ -1994,11 +2009,11 @@ describe('model: findOneAndUpdate:', function() {
         calls.push({ collection: collection, fnName: fnName });
       });
 
-      const Model = m.model('gh7108', { name: String });
+      const Model = m.model('Test', { name: String });
       const update = { name: 'test' };
       Model.findOneAndUpdate({}, update, {}, function() {
         assert.equal(calls.length, 1);
-        assert.equal(calls[0].collection, 'gh7108');
+        assert.equal(calls[0].collection, 'tests');
         assert.equal(calls[0].fnName, 'findOneAndUpdate');
         m.disconnect();
         done();
@@ -2023,7 +2038,7 @@ describe('model: findOneAndUpdate:', function() {
           location: String
         });
 
-        const Model = m.model('gh6887', schema);
+        const Model = m.model('Test', schema);
 
         const options = { overwrite: true, new: true };
         const doc = yield Model.create({ name: 'Jennifer', location: 'Taipei' });
@@ -2039,8 +2054,8 @@ describe('model: findOneAndUpdate:', function() {
         assert.strictEqual(newDoc2.location, 'Hsinchu');
 
         assert.equal(calls.length, 3);
-        assert.equal(calls[1].collection, 'gh6887');
-        assert.equal(calls[1].collection, 'gh6887');
+        assert.equal(calls[1].collection, 'tests');
+        assert.equal(calls[1].collection, 'tests');
         assert.equal(calls[2].fnName, 'findOneAndReplace');
         assert.equal(calls[2].fnName, 'findOneAndReplace');
 
@@ -2078,7 +2093,7 @@ describe('model: findOneAndUpdate:', function() {
         highlights: [highlightSchema]
       });
 
-      const Model = db.model('gh6240', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({
@@ -2144,7 +2159,7 @@ describe('model: findOneAndUpdate:', function() {
         this.update({},{ $set: {lastUpdate: new Date()} });
       });
 
-      const User = db.model('gh5702', UserSchema);
+      const User = db.model('User', UserSchema);
 
       const friendId = uuid.v4();
       const user = {
@@ -2190,7 +2205,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const User = db.model('gh5551', UserSchema);
+      const User = db.model('User', UserSchema);
 
       const user = { name: 'upsert', foo: uuid.v4() };
       const opts = {
@@ -2221,7 +2236,7 @@ describe('model: findOneAndUpdate:', function() {
         locations: [locationSchema]
       });
 
-      const T = db.model('gh4724', testSchema);
+      const T = db.model('Test', testSchema);
 
       const t = new T({
         locations: [{
@@ -2256,7 +2271,7 @@ describe('model: findOneAndUpdate:', function() {
         return true;
       });
 
-      B = db.model('b', B);
+      B = db.model('Test', B);
 
       B.findOneAndUpdate(
         {foo: 'bar'},
@@ -2280,7 +2295,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const Book = db.model('gh7679', bookSchema);
+      const Book = db.model('Book', bookSchema);
 
       return Book.findOneAndUpdate({}, { genres: ['Sci-Fi'] }, { upsert: true }).
         then(() => Book.findOne()).
@@ -2297,7 +2312,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const Model = db.model('gh6889', schema);
+      const Model = db.model('Test', schema);
 
       const opts = { runValidators: true };
       return Model.findOneAndUpdate({}, { $pull: { arr: { x: 'three' } } }, opts);
@@ -2316,7 +2331,7 @@ describe('model: findOneAndUpdate:', function() {
       });
 
       return co(function*() {
-        const Model = db.model('gh6972', schema);
+        const Model = db.model('Test', schema);
         yield Model.findOneAndUpdate({}, {
           $pull: {someArray: {innerField: '507f191e810c19729de860ea'}}
         }, {
@@ -2328,7 +2343,7 @@ describe('model: findOneAndUpdate:', function() {
 
   it('with versionKey in top-level and a `$` key (gh-7003)', function() {
     const schema = new Schema({ name: String });
-    const Model = db.model('gh7003', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let doc = yield Model.create({ name: 'test', __v: 10 });
@@ -2345,7 +2360,7 @@ describe('model: findOneAndUpdate:', function() {
 
   it('empty update with timestamps (gh-7041)', function() {
     const schema = new Schema({ name: String }, { timestamps: true });
-    const Model = db.model('gh7041', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let doc = yield Model.create({ name: 'test' });
@@ -2357,7 +2372,7 @@ describe('model: findOneAndUpdate:', function() {
 
   it('skipping updatedAt and createdAt (gh-3934)', function() {
     const schema = new Schema({ name: String }, { timestamps: true });
-    const Model = db.model('gh3934', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let doc = yield Model.findOneAndUpdate({}, { name: 'test' }, {
@@ -2377,7 +2392,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('runs lowercase on $addToSet, $push, etc (gh-4185)', function() {
-    const Cat = db.model('gh4185', {
+    const Cat = db.model('Test', {
       _id: String,
       myArr: { type: [{type: String, lowercase: true}], default: undefined }
     });
@@ -2392,7 +2407,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('returnOriginal (gh-7846)', function() {
-    const Cat = db.model('gh7846_update', {
+    const Cat = db.model('Cat', {
       name: String
     });
 
@@ -2414,7 +2429,7 @@ describe('model: findOneAndUpdate:', function() {
     schema.path('shape').discriminator('gh8378_Square',
       Schema({ side: Number, color: String }));
 
-    const MyModel = db.model('gh8378_Shape', schema);
+    const MyModel = db.model('Test', schema);
 
     return co(function*() {
       let doc = yield MyModel.create({
@@ -2439,7 +2454,7 @@ describe('model: findOneAndUpdate:', function() {
 
   it('setDefaultsOnInsert with doubly nested subdocs (gh-8392)', function() {
     const nestedSchema = Schema({ name: String });
-    const Model = db.model('gh8392', Schema({
+    const Model = db.model('Test', Schema({
       L1: Schema({
         L2: {
           type: nestedSchema,
@@ -2471,7 +2486,7 @@ describe('model: findOneAndUpdate:', function() {
       }
     });
 
-    const User = db.model('gh8444', userSchema);
+    const User = db.model('User', userSchema);
 
     return co(function*() {
       const doc = yield User.findOneAndUpdate({}, {
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 9d27f4ebe5c..8a767e91be6 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -26,11 +26,11 @@ describe('model: update:', function() {
   let id1;
   let Comments;
   let BlogPost;
-  let collection;
-  let strictSchema;
   let db;
 
-  before(function() {
+  beforeEach(function() {
+    db = start();
+
     Comments = new Schema({});
 
     Comments.add({
@@ -40,7 +40,7 @@ describe('model: update:', function() {
       comments: [Comments]
     });
 
-    BlogPost = new Schema({
+    const schema = new Schema({
       title: String,
       author: String,
       slug: String,
@@ -56,7 +56,7 @@ describe('model: update:', function() {
       comments: [Comments]
     }, {strict: false});
 
-    BlogPost.virtual('titleWithAuthor')
+    schema.virtual('titleWithAuthor')
       .get(function() {
         return this.get('title') + ' by ' + this.get('author');
       })
@@ -66,35 +66,22 @@ describe('model: update:', function() {
         this.set('author', split[1]);
       });
 
-    BlogPost.method('cool', function() {
+    schema.method('cool', function() {
       return this;
     });
 
-    BlogPost.static('woot', function() {
+    schema.static('woot', function() {
       return this;
     });
 
-    mongoose.model('BlogPostForUpdates', BlogPost);
-
-    collection = 'blogposts_' + random();
-
-    strictSchema = new Schema({name: String, x: {nested: String}});
-    strictSchema.virtual('foo').get(function() {
-      return 'i am a virtual FOO!';
-    });
-    mongoose.model('UpdateStrictSchema', strictSchema);
-
-    db = start();
+    BlogPost = db.model('BlogPost', schema);
   });
 
   after(function(done) {
     db.close(done);
   });
 
-  beforeEach(function(done) {
-    const db = start();
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
+  beforeEach(function() {
     id0 = new DocumentObjectId;
     id1 = new DocumentObjectId;
 
@@ -109,15 +96,25 @@ describe('model: update:', function() {
     post.owners = [id0, id1];
     post.comments = [{body: 'been there'}, {body: 'done that'}];
 
-    post.save(function(err) {
-      assert.ifError(err);
-      db.close(done);
-    });
+    return post.save();
   });
 
-  it('works', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => {
+    const arr = [];
 
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
+  it('works', function(done) {
     BlogPost.findById(post._id, function(err, cf) {
       assert.ifError(err);
       assert.equal(cf.title, title);
@@ -228,8 +225,6 @@ describe('model: update:', function() {
   });
 
   it('casts doc arrays', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     const update = {
       comments: [{body: 'worked great'}],
       $set: {'numbers.1': 100},
@@ -255,8 +250,6 @@ describe('model: update:', function() {
   });
 
   it('makes copy of conditions and update options', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     const conditions = {'_id': post._id.toString()};
     const update = {'$set': {'some_attrib': post._id.toString()}};
     BlogPost.update(conditions, update, function(err) {
@@ -267,8 +260,6 @@ describe('model: update:', function() {
   });
 
   it('$addToSet with $ (gh-479)', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     function a() {
     }
 
@@ -298,15 +289,10 @@ describe('model: update:', function() {
   });
 
   describe('using last', function() {
-    let BlogPost;
     let last;
 
-    before(function() {
-      BlogPost = db.model('BlogPostForUpdates', collection);
-    });
-
     beforeEach(function(done) {
-      BlogPost.findOne({}, function(error, doc) {
+      BlogPost.findOne({ 'owners.1': { $exists: true } }, function(error, doc) {
         assert.ifError(error);
         last = doc;
         done();
@@ -335,6 +321,7 @@ describe('model: update:', function() {
 
     it('handles $addToSet (gh-545)', function(done) {
       const owner = last.owners[0];
+      assert.ok(owner);
       const numOwners = last.owners.length;
       const update = {
         $addToSet: {owners: owner}
@@ -395,8 +382,6 @@ describe('model: update:', function() {
   });
 
   it('works with nested positional notation', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     const update = {
       $set: {
         'comments.0.comments.0.date': '11/5/2011',
@@ -419,8 +404,6 @@ describe('model: update:', function() {
   });
 
   it('handles $pull with obj literal (gh-542)', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     BlogPost.findById(post, function(err, doc) {
       assert.ifError(err);
 
@@ -441,8 +424,6 @@ describe('model: update:', function() {
   });
 
   it('handles $pull of obj literal and nested $in', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     const update = {
       $pull: {comments: {body: {$in: ['been there']}}}
     };
@@ -460,8 +441,6 @@ describe('model: update:', function() {
   });
 
   it('handles $pull and nested $nin', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
-
     BlogPost.findById(post, function(err, doc) {
       assert.ifError(err);
 
@@ -491,7 +470,6 @@ describe('model: update:', function() {
   });
 
   it('updates numbers atomically', function(done) {
-    const BlogPost = db.model('BlogPostForUpdates', collection);
     let totalDocs = 4;
 
     const post = new BlogPost;
@@ -518,64 +496,18 @@ describe('model: update:', function() {
     });
   });
 
-  describe('honors strict schemas', function() {
-    it('(gh-699)', function(done) {
-      const S = db.model('UpdateStrictSchema');
-
-      let doc = S.find()._castUpdate({ignore: true});
-      assert.equal(doc, false);
-      doc = S.find()._castUpdate({$unset: {x: 1}});
-      assert.equal(Object.keys(doc.$unset).length, 1);
-      done();
-    });
-
-    it('works', function(done) {
-      const S = db.model('UpdateStrictSchema');
-      const s = new S({name: 'orange crush'});
-
-      s.save(function(err) {
-        assert.ifError(err);
-
-        S.update({_id: s._id}, {ignore: true}, function(err, affected) {
-          assert.ifError(err);
-          assert.equal(affected.n, 0);
-
-          S.findById(s._id, function(err, doc) {
-            assert.ifError(err);
-            assert.ok(!doc.ignore);
-            assert.ok(!doc._doc.ignore);
-
-            S.update({_id: s._id}, {name: 'Drukqs', foo: 'fooey'}, function(err, affected) {
-              assert.ifError(err);
-              assert.equal(affected.n, 1);
-
-              S.findById(s._id, function(err, doc) {
-                assert.ifError(err);
-                assert.ok(!doc._doc.foo);
-                done();
-              });
-            });
-          });
-        });
-      });
-    });
-  });
-
-  it('passes number of affected docs', function(done) {
-    const B = db.model('BlogPostForUpdates', 'wwwwowowo' + random());
+  it('passes number of affected docs', function() {
+    return co(function*() {
+      yield BlogPost.deleteMany({});
+      yield BlogPost.create({title: 'one'}, {title: 'two'}, {title: 'three'});
 
-    B.create({title: 'one'}, {title: 'two'}, {title: 'three'}, function(err) {
-      assert.ifError(err);
-      B.update({}, {title: 'newtitle'}, {multi: true}, function(err, affected) {
-        assert.ifError(err);
-        assert.equal(affected.n, 3);
-        done();
-      });
+      const res = yield BlogPost.update({}, {title: 'newtitle'}, {multi: true});
+      assert.equal(res.n, 3);
     });
   });
 
   it('updates a number to null (gh-640)', function(done) {
-    const B = db.model('BlogPostForUpdates', 'wwwwowowo' + random());
+    const B = BlogPost;
     const b = new B({meta: {visitors: null}});
     b.save(function(err) {
       assert.ifError(err);

From 1aeaa548fef984ccb3281aec4d580dc42dc36f44 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 22:08:52 -0500
Subject: [PATCH 0423/2348] test(document): repro #8514

---
 test/document.test.js | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 7acad6d6bf6..aa90f45a210 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8621,4 +8621,15 @@ describe('document', function() {
       assert.ok(!res[1].hasOwnProperty('beta'));
     });
   });
+
+  it('creates document array defaults in forward order, not reverse (gh-8514)', function() {
+    let num = 0;
+    const schema = Schema({
+      arr: [{ val: { type: Number, default: () => ++num } }]
+    });
+    const Model = db.model('Test', schema);
+
+    const doc = new Model({ arr: [{}, {}, {}] });
+    assert.deepEqual(doc.toObject().arr.map(v => v.val), [1, 2, 3]);
+  });
 });

From cb71d573d6ce8724e0ef7c33854efe91657c5345 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jan 2020 22:09:06 -0500
Subject: [PATCH 0424/2348] fix(document): create document array defaults in
 forward order, not reverse

Fix #8514
---
 lib/schema/documentarray.js | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index c8e72aaf20c..3ec0e3cc27d 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -363,7 +363,6 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
 
   let selected;
   let subdoc;
-  let i;
   const _opts = { transform: false, virtuals: false };
 
   if (!Array.isArray(value)) {
@@ -387,9 +386,9 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
     value = new MongooseDocumentArray(value, this.path, doc);
   }
 
-  i = value.length;
+  const len = value.length;
 
-  while (i--) {
+  for (let i = 0; i < len; ++i) {
     if (!value[i]) {
       continue;
     }

From fc6571b3cc6182b9ab52b88a97f636371c7faa99 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jan 2020 19:08:33 -0500
Subject: [PATCH 0425/2348] test(populate): repro #8527

---
 test/model.populate.test.js | 49 +++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index bebcb262f69..969e896e05b 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9027,4 +9027,53 @@ describe('model: populate:', function() {
       assert.equal(doc.childCount, 1);
     });
   });
+
+  it('works when embedded discriminator array has populated path but not refPath (gh-8527)', function() {
+    const Image = db.model('Image', Schema({ imageName: String }));
+    const Text = db.model('Text', Schema({ textName: String }));
+    const ItemSchema = Schema({ objectType: String }, {
+      discriminatorKey: 'objectType',
+      _id: false
+    });
+
+    const noId = { _id: false };
+
+    const NestedDataSchema = Schema({
+      data: Schema({ title: String, description: String }, noId),
+    }, noId);
+  
+    const InternalItemSchemaGen = () => Schema({
+      data: { 
+        type: ObjectId,
+        refPath: 'list.objectType',
+      }
+    }, noId);
+  
+    const externalSchema = Schema({ data: { sourceId: Number } }, noId);
+
+    const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
+    ExampleSchema.path('list').discriminator('Image', InternalItemSchemaGen());
+    ExampleSchema.path('list').discriminator('Text', InternalItemSchemaGen());
+    ExampleSchema.path('list').discriminator('ExternalSource', externalSchema);
+    ExampleSchema.path('list').discriminator('NestedData', NestedDataSchema);
+    const Example = db.model('Test', ExampleSchema);
+
+    return co(function*() {
+      const image1 = yield Image.create({ imageName: '01image' });
+      const text1 = yield Text.create({ textName: '01text' });
+
+      const example = yield Example.create({
+        test: 'example',
+        list: [
+          { data: image1._id, objectType: 'Image' },
+          { data: text1._id, objectType: 'Text' },
+          { data: { sourceId: 123 }, objectType: 'ExternalSource' },
+          { data: { title: 'test' }, objectType: 'NestedData' }
+        ]
+      });
+
+      const res = yield Example.findById(example).populate('list.data').lean();
+      assert.deepEqual(res.list[3].data, { title: 'test' });
+    });
+  });
 });

From 312355c1c12117f2f9f6ab00d67aa9170318e9eb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jan 2020 19:08:47 -0500
Subject: [PATCH 0426/2348] fix(populate): don't try to populate embedded
 discriminator that has populated path but no `refPath`

Fix #8527
---
 lib/helpers/populate/getModelsMapForPopulate.js | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 7bd6d34d1dd..b7b5982cdf0 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -50,14 +50,19 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     if (Array.isArray(schema)) {
       for (let j = 0; j < schema.length; ++j) {
         let _modelNames;
+        let res;
         try {
-          const res = _getModelNames(doc, schema[j]);
+          res = _getModelNames(doc, schema[j]);
           _modelNames = res.modelNames;
-          isRefPath = res.isRefPath;
-          normalizedRefPath = res.refPath;
+          isRefPath = isRefPath || res.isRefPath;
+          normalizedRefPath = normalizedRefPath || res.refPath;
         } catch (error) {
           return error;
         }
+
+        if (isRefPath && !res.isRefPath) {
+          continue;
+        }
         if (!_modelNames) {
           continue;
         }
@@ -218,7 +223,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
               ret = ret.map(v => v === docValue ? SkipPopulateValue(v) : v);
               continue;
             }
-            modelNames.push(utils.getValue(pieces.slice(i + 1).join('.'), subdoc));
+            const modelName = utils.getValue(pieces.slice(i + 1).join('.'), subdoc);
+            modelNames.push(modelName);
           }
         }
       }

From 8fd570ead1a502cc223f4a6227c6f84fbe0b79e6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jan 2020 19:11:23 -0500
Subject: [PATCH 0427/2348] style: fix lint

---
 test/model.populate.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 969e896e05b..edbcbc2cf34 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9041,14 +9041,14 @@ describe('model: populate:', function() {
     const NestedDataSchema = Schema({
       data: Schema({ title: String, description: String }, noId),
     }, noId);
-  
+
     const InternalItemSchemaGen = () => Schema({
-      data: { 
+      data: {
         type: ObjectId,
         refPath: 'list.objectType',
       }
     }, noId);
-  
+
     const externalSchema = Schema({ data: { sourceId: Number } }, noId);
 
     const ExampleSchema = Schema({ test: String, list: [ItemSchema] });

From 5a3fdb8e1674b64036d6a67fcad5228b1ba35290 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jan 2020 19:41:04 -0500
Subject: [PATCH 0428/2348] doc(connections): document `authSource` option

Fix #8517
---
 docs/connections.pug | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 119619f7cdd..dd9375cc7e7 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -148,6 +148,7 @@ block content
     * `connectTimeoutMS`  - How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
     * `socketTimeoutMS`   - How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
     * `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
+    * `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
 
     The following options are important for tuning Mongoose only if you are
     running **without** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
@@ -205,7 +206,7 @@ block content
     in the query string.
 
     ```javascript
-    mongoose.connect('mongodb://localhost:27017/test?connectTimeoutMS=1000&bufferCommands=false');
+    mongoose.connect('mongodb://localhost:27017/test?connectTimeoutMS=1000&bufferCommands=false&authSource=otherdb');
     // The above is equivalent to:
     mongoose.connect('mongodb://localhost:27017/test', {
       connectTimeoutMS: 1000
@@ -222,7 +223,12 @@ block content
     like `connectTimeoutMS` or `poolSize`, in the options object.
 
     The MongoDB docs have a full list of
-    [supported connection string options](https://docs.mongodb.com/manual/reference/connection-string/)
+    [supported connection string options](https://docs.mongodb.com/manual/reference/connection-string/).
+    Below are some options that are often useful to set in the connection string because they
+    are closely associated with the hostname and authentication information.
+
+    * `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
+    * `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
 
     <h3 id="connection-events"><a href="#connection-events">Connection Events</a></h3>
 

From abd6197d5450a216007af79b8bf5efef67e2b2ee Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jan 2020 22:33:07 -0500
Subject: [PATCH 0429/2348] test(model): reuse collections where possible re:
 #8481

---
 test/model.test.js | 873 ++++++++++++++++-----------------------------
 1 file changed, 307 insertions(+), 566 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 3087ef3b346..df34878f671 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -22,13 +22,12 @@ const MongooseError = mongoose.Error;
 
 describe('Model', function() {
   let db;
-  let Test;
   let Comments;
   let BlogPost;
-  let bpSchema;
-  let collection;
 
-  before(function() {
+  beforeEach(() => db.deleteModel(/.*/));
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -74,33 +73,38 @@ describe('Model', function() {
       return this;
     });
 
-    mongoose.model('BlogPost', BlogPost);
-    bpSchema = BlogPost;
-
-    collection = 'blogposts_' + random();
+    BlogPost = db.model('BlogPost', BlogPost);
   });
 
   before(function() {
     db = start();
-    const testSchema = new Schema({
-      _id: {
-        first_name: {type: String},
-        age: {type: Number}
-      },
-      last_name: {type: String},
-      doc_embed: {
-        some: {type: String}
-      }
-
-    });
-    Test = db.model('test-schema', testSchema);
   });
 
   after(function() {
     db.close();
   });
 
+  afterEach(() => {
+    const arr = [];
+
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
   it('can be created using _id as embedded document', function(done) {
+    const Test = db.model('Test', Schema({
+      _id: { first_name: String, age: Number },
+      last_name: String,
+      doc_embed: {
+        some: String
+      }
+    }));
     const t = new Test({
       _id: {
         first_name: 'Daniel',
@@ -134,19 +138,17 @@ describe('Model', function() {
 
   describe('constructor', function() {
     it('works without "new" keyword', function(done) {
-      let B = mongoose.model('BlogPost');
+      const B = BlogPost;
       let b = B();
       assert.ok(b instanceof B);
-      B = db.model('BlogPost');
       b = B();
       assert.ok(b instanceof B);
       done();
     });
     it('works "new" keyword', function(done) {
-      let B = mongoose.model('BlogPost');
+      const B = BlogPost;
       let b = new B();
       assert.ok(b instanceof B);
-      B = db.model('BlogPost');
       b = new B();
       assert.ok(b instanceof B);
       done();
@@ -154,44 +156,19 @@ describe('Model', function() {
   });
   describe('isNew', function() {
     it('is true on instantiation', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       const post = new BlogPost;
       assert.equal(post.isNew, true);
       done();
     });
-
-    it('on parent and subdocs on failed inserts', function(done) {
-      const schema = new Schema({
-        name: {type: String, unique: true},
-        em: [new Schema({x: Number})]
-      }, {collection: 'testisnewonfail_' + random()});
-
-      const A = db.model('isNewOnFail', schema);
-
-      A.on('index', function() {
-        const a = new A({name: 'i am new', em: [{x: 1}]});
-        a.save(function(err) {
-          assert.ifError(err);
-          assert.equal(a.isNew, false);
-          assert.equal(a.em[0].isNew, false);
-          const b = new A({name: 'i am new', em: [{x: 2}]});
-          b.save(function(err) {
-            assert.ok(err);
-            assert.equal(b.isNew, true);
-            assert.equal(b.em[0].isNew, true);
-            done();
-          });
-        });
-      });
-    });
   });
 
   it('gh-2140', function(done) {
+    db.deleteModel(/Test/);
     const S = new Schema({
       field: [{text: String}]
     });
 
-    const Model = db.model('gh-2140', S, 'gh-2140');
+    const Model = db.model('Test', S);
     const s = new Model();
     s.field = [null];
     s.field = [{text: 'text'}];
@@ -202,8 +179,6 @@ describe('Model', function() {
 
   describe('schema', function() {
     it('should exist', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       assert.ok(BlogPost.schema instanceof Schema);
       assert.ok(BlogPost.prototype.schema instanceof Schema);
       done();
@@ -216,7 +191,8 @@ describe('Model', function() {
         model = model_;
       });
 
-      const Named = db.model('EmitInitOnSchema', schema);
+      db.deleteModel(/Test/);
+      const Named = db.model('Test', schema);
       assert.equal(model, Named);
       done();
     });
@@ -224,8 +200,6 @@ describe('Model', function() {
 
   describe('structure', function() {
     it('default when instantiated', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost;
       assert.equal(post.db.model('BlogPost').modelName, 'BlogPost');
       assert.equal(post.constructor.modelName, 'BlogPost');
@@ -258,8 +232,7 @@ describe('Model', function() {
             arr: {type: Array, cast: String, default: ['a', 'b', 'c']},
             single: {type: Array, cast: String, default: ['a']}
           });
-          mongoose.model('DefaultArray', DefaultArraySchema);
-          const DefaultArray = db.model('DefaultArray', collection);
+          const DefaultArray = db.model('Test', DefaultArraySchema);
           const arr = new DefaultArray;
           assert.equal(arr.get('arr').length, 3);
           assert.equal(arr.get('arr')[0], 'a');
@@ -275,8 +248,7 @@ describe('Model', function() {
             arr: {type: Array, cast: String, default: []},
             auto: [Number]
           });
-          mongoose.model('DefaultZeroCardArray', DefaultZeroCardArraySchema);
-          const DefaultZeroCardArray = db.model('DefaultZeroCardArray', collection);
+          const DefaultZeroCardArray = db.model('Test', DefaultZeroCardArraySchema);
           const arr = new DefaultZeroCardArray();
           assert.equal(arr.get('arr').length, 0);
           assert.equal(arr.arr.length, 0);
@@ -287,8 +259,6 @@ describe('Model', function() {
     });
 
     it('a hash with one null value', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost({
         title: null
       });
@@ -297,7 +267,6 @@ describe('Model', function() {
     });
 
     it('when saved', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       let pending = 2;
 
       function cb() {
@@ -348,8 +317,6 @@ describe('Model', function() {
 
     describe('init', function() {
       it('works', function(done) {
-        const BlogPost = db.model('BlogPost', collection);
-
         const post = new BlogPost();
 
         post.init({
@@ -403,8 +370,6 @@ describe('Model', function() {
       });
 
       it('partially', function(done) {
-        const BlogPost = db.model('BlogPost', collection);
-
         const post = new BlogPost;
         post.init({
           title: 'Test',
@@ -428,8 +393,6 @@ describe('Model', function() {
       });
 
       it('with partial hash', function(done) {
-        const BlogPost = db.model('BlogPost', collection);
-
         const post = new BlogPost({
           meta: {
             date: new Date,
@@ -442,8 +405,6 @@ describe('Model', function() {
       });
 
       it('isNew on embedded documents', function(done) {
-        const BlogPost = db.model('BlogPost', collection);
-
         const post = new BlogPost();
         post.init({
           title: 'Test',
@@ -456,8 +417,6 @@ describe('Model', function() {
       });
 
       it('isNew on embedded documents after saving', function(done) {
-        const BlogPost = db.model('BlogPost', collection);
-
         const post = new BlogPost({title: 'hocus pocus'});
         post.comments.push({title: 'Humpty Dumpty', comments: [{title: 'nested'}]});
         assert.equal(post.get('comments')[0].isNew, true);
@@ -480,19 +439,17 @@ describe('Model', function() {
   });
 
   it('collection name can be specified through schema', function(done) {
-    const schema = new Schema({name: String}, {collection: 'users1'});
+    const schema = new Schema({name: String}, {collection: 'tests'});
     const Named = mongoose.model('CollectionNamedInSchema1', schema);
-    assert.equal(Named.prototype.collection.name, 'users1');
+    assert.equal(Named.prototype.collection.name, 'tests');
 
-    const users2schema = new Schema({name: String}, {collection: 'users2'});
-    const Named2 = db.model('CollectionNamedInSchema2', users2schema);
-    assert.equal(Named2.prototype.collection.name, 'users2');
+    const users2schema = new Schema({name: String}, {collection: 'tests'});
+    const Named2 = db.model('FooBar', users2schema);
+    assert.equal(Named2.prototype.collection.name, 'tests');
     done();
   });
 
   it('saving a model with a null value should perpetuate that null value to the db', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost({
       title: null
     });
@@ -529,7 +486,7 @@ describe('Model', function() {
       next();
     });
 
-    const Parent = db.model('doc', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     const parent = new Parent({
       name: 'Bob',
@@ -552,8 +509,6 @@ describe('Model', function() {
   });
 
   it('instantiating a model with a hash that maps to at least 1 undefined value', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost({
       title: undefined
     });
@@ -575,7 +530,7 @@ describe('Model', function() {
       }
     });
 
-    const M = db.model('NestedObjectWithMongooseNumber', schema);
+    const M = db.model('Test', schema);
     const m = new M;
     m.nested = null;
     m.save(function(err) {
@@ -598,7 +553,7 @@ describe('Model', function() {
       name: String
     });
 
-    const MyModel = db.model('MyModel', MySchema, 'numberrangeerror' + random());
+    const MyModel = db.model('Test', MySchema);
 
     const instance = new MyModel({
       name: 'test',
@@ -619,8 +574,6 @@ describe('Model', function() {
   });
 
   it('over-writing a number should persist to the db (gh-342)', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost({
       meta: {
         date: new Date,
@@ -644,8 +597,6 @@ describe('Model', function() {
 
   describe('methods', function() {
     it('can be defined', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost();
       assert.equal(post.cool(), post);
       done();
@@ -661,8 +612,8 @@ describe('Model', function() {
         children: [ChildSchema]
       });
 
-      const ChildA = db.model('ChildA', ChildSchema, 'children_' + random());
-      const ParentA = db.model('ParentA', ParentSchema, 'parents_' + random());
+      const ChildA = db.model('Child', ChildSchema);
+      const ParentA = db.model('Parent', ParentSchema);
 
       const c = new ChildA;
       assert.equal(typeof c.talk, 'function');
@@ -680,7 +631,7 @@ describe('Model', function() {
           return this;
         }
       });
-      const NestedKey = db.model('NestedKey', NestedKeySchema);
+      const NestedKey = db.model('Test', NestedKeySchema);
       const n = new NestedKey();
       assert.equal(n.foo.bar(), n);
       done();
@@ -689,8 +640,6 @@ describe('Model', function() {
 
   describe('statics', function() {
     it('can be defined', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       assert.equal(BlogPost.woot(), BlogPost);
       done();
     });
@@ -698,7 +647,6 @@ describe('Model', function() {
 
   describe('casting as validation errors', function() {
     it('error', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       let threw = false;
 
       let post;
@@ -731,7 +679,6 @@ describe('Model', function() {
       });
     });
     it('nested error', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       let threw = false;
 
       const post = new BlogPost;
@@ -765,8 +712,6 @@ describe('Model', function() {
 
 
     it('subdocument cast error', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost({
         title: 'Test',
         slug: 'test',
@@ -788,7 +733,7 @@ describe('Model', function() {
         return false;
       }
 
-      const db = start();
+      db.deleteModel(/BlogPost/);
       const subs = new Schema({
         str: {
           type: String, validate: failingvalidator
@@ -802,7 +747,6 @@ describe('Model', function() {
       });
 
       post.save(function(err) {
-        db.close();
         assert.ok(err instanceof ValidationError);
         done();
       });
@@ -810,7 +754,6 @@ describe('Model', function() {
 
 
     it('subdocument error when adding a subdoc', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       let threw = false;
 
       const post = new BlogPost();
@@ -834,8 +777,6 @@ describe('Model', function() {
 
 
     it('updates', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost();
       post.set('title', '1');
 
@@ -857,7 +798,6 @@ describe('Model', function() {
     });
 
     it('$pull', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       const post = new BlogPost();
 
       post.get('numbers').push('3');
@@ -866,7 +806,6 @@ describe('Model', function() {
     });
 
     it('$push', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       const post = new BlogPost();
 
       post.get('numbers').push(1, 2, 3, 4);
@@ -886,8 +825,6 @@ describe('Model', function() {
     });
 
     it('Number arrays', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost();
       post.numbers.push(1, '2', 3);
 
@@ -934,7 +871,7 @@ describe('Model', function() {
         valid: {type: Boolean, default: true}
       });
 
-      const M = db.model('gh502', S);
+      const M = db.model('Test', S);
 
       const m = new M;
       m.save(function(err) {
@@ -966,14 +903,12 @@ describe('Model', function() {
         return global.Promise.resolve(true);
       }
 
-      mongoose.model('TestValidation', new Schema({
+      const TestValidation = db.model('Test', new Schema({
         simple: {type: String, required: true},
         scope: {type: String, validate: [dovalidate, 'scope failed'], required: true},
         asyncScope: {type: String, validate: [dovalidateAsync, 'async scope failed'], required: true}
       }));
 
-      const TestValidation = db.model('TestValidation');
-
       const post = new TestValidation();
       post.set('simple', '');
       post.set('scope', 'correct');
@@ -996,12 +931,10 @@ describe('Model', function() {
         return val === 'abc';
       }
 
-      mongoose.model('TestValidationMessage', new Schema({
+      const TestValidationMessage = db.model('Test', new Schema({
         simple: {type: String, validate: [validate, 'must be abc']}
       }));
 
-      const TestValidationMessage = db.model('TestValidationMessage');
-
       const post = new TestValidationMessage();
       post.set('simple', '');
 
@@ -1024,7 +957,7 @@ describe('Model', function() {
       const IntrospectionValidationSchema = new Schema({
         name: String
       });
-      const IntrospectionValidation = db.model('IntrospectionValidation', IntrospectionValidationSchema, 'introspections_' + random());
+      const IntrospectionValidation = db.model('Test', IntrospectionValidationSchema);
       IntrospectionValidation.schema.path('name').validate(function(value) {
         return value.length < 2;
       }, 'Name cannot be greater than 1 character for path "{PATH}" with value `{VALUE}`');
@@ -1032,18 +965,16 @@ describe('Model', function() {
       doc.save(function(err) {
         assert.equal(err.errors.name.message, 'Name cannot be greater than 1 character for path "name" with value `hi`');
         assert.equal(err.name, 'ValidationError');
-        assert.ok(err.message.indexOf('IntrospectionValidation validation failed') !== -1, err.message);
+        assert.ok(err.message.indexOf('Test validation failed') !== -1, err.message);
         done();
       });
     });
 
     it('of required undefined values', function(done) {
-      mongoose.model('TestUndefinedValidation', new Schema({
+      const TestUndefinedValidation = db.model('Test', new Schema({
         simple: {type: String, required: true}
       }));
 
-      const TestUndefinedValidation = db.model('TestUndefinedValidation');
-
       const post = new TestUndefinedValidation;
 
       post.save(function(err) {
@@ -1059,7 +990,7 @@ describe('Model', function() {
     });
 
     it('save callback should only execute once (gh-319)', function(done) {
-      const D = db.model('CallbackFiresOnceValidation', new Schema({
+      const D = db.model('Test', new Schema({
         username: {type: String, validate: /^[a-z]{6}$/i},
         email: {type: String, validate: /^[a-z]{6}$/i},
         password: {type: String, validate: /^[a-z]{6}$/i}
@@ -1099,12 +1030,10 @@ describe('Model', function() {
     });
 
     it('query result', function(done) {
-      mongoose.model('TestValidationOnResult', new Schema({
+      const TestV = db.model('Test', new Schema({
         resultv: {type: String, required: true}
       }));
 
-      const TestV = db.model('TestValidationOnResult');
-
       const post = new TestV;
 
       post.validate(function(err) {
@@ -1127,13 +1056,11 @@ describe('Model', function() {
     });
 
     it('of required previously existing null values', function(done) {
-      mongoose.model('TestPreviousNullValidation', new Schema({
+      const TestP = db.model('Test', new Schema({
         previous: {type: String, required: true},
         a: String
       }));
 
-      const TestP = db.model('TestPreviousNullValidation');
-
       TestP.collection.insertOne({a: null, previous: null}, {}, function(err, f) {
         assert.ifError(err);
         TestP.findOne({_id: f.ops[0]._id}, function(err, found) {
@@ -1156,14 +1083,12 @@ describe('Model', function() {
     });
 
     it('nested', function(done) {
-      mongoose.model('TestNestedValidation', new Schema({
+      const TestNestedValidation = db.model('Test', new Schema({
         nested: {
           required: {type: String, required: true}
         }
       }));
 
-      const TestNestedValidation = db.model('TestNestedValidation');
-
       const post = new TestNestedValidation();
       post.set('nested.required', null);
 
@@ -1187,12 +1112,10 @@ describe('Model', function() {
         subs: [Subsubdocs]
       });
 
-      mongoose.model('TestSubdocumentsValidation', new Schema({
+      const TestSubdocumentsValidation = db.model('Test', new Schema({
         items: [Subdocs]
       }));
 
-      const TestSubdocumentsValidation = db.model('TestSubdocumentsValidation');
-
       const post = new TestSubdocumentsValidation();
 
       post.get('items').push({required: '', subs: [{required: ''}]});
@@ -1233,12 +1156,10 @@ describe('Model', function() {
     });
 
     it('without saving', function(done) {
-      mongoose.model('TestCallingValidation', new Schema({
+      const TestCallingValidation = db.model('Test', new Schema({
         item: {type: String, required: true}
       }));
 
-      const TestCallingValidation = db.model('TestCallingValidation');
-
       const post = new TestCallingValidation;
 
       assert.equal(post.schema.path('item').isRequired, true);
@@ -1263,12 +1184,10 @@ describe('Model', function() {
         return true;
       }
 
-      mongoose.model('TestRequiredFalse', new Schema({
+      const TestV = db.model('Test', new Schema({
         result: {type: String, validate: [validator, 'chump validator'], required: false}
       }));
 
-      const TestV = db.model('TestRequiredFalse');
-
       const post = new TestV;
 
       assert.equal(post.schema.path('result').isRequired, false);
@@ -1292,9 +1211,7 @@ describe('Model', function() {
           next();
         });
 
-        mongoose.model('ValidationMiddleware', ValidationMiddlewareSchema);
-
-        Post = db.model('ValidationMiddleware');
+        Post = db.model('Test', ValidationMiddlewareSchema);
         post = new Post();
         post.set({baz: 'bad'});
 
@@ -1332,9 +1249,7 @@ describe('Model', function() {
           next();
         });
 
-        mongoose.model('AsyncValidationMiddleware', AsyncValidationMiddlewareSchema);
-
-        Post = db.model('AsyncValidationMiddleware');
+        Post = db.model('Test', AsyncValidationMiddlewareSchema);
         post = new Post();
         post.set({prop: 'bad'});
 
@@ -1376,9 +1291,7 @@ describe('Model', function() {
           next();
         });
 
-        mongoose.model('ComplexValidationMiddleware', ComplexValidationMiddlewareSchema);
-
-        Post = db.model('ComplexValidationMiddleware');
+        Post = db.model('Test', ComplexValidationMiddlewareSchema);
         post = new Post();
         post.set({
           baz: 'bad',
@@ -1425,12 +1338,10 @@ describe('Model', function() {
     it('works', function(done) {
       const now = Date.now();
 
-      mongoose.model('TestDefaults', new Schema({
+      const TestDefaults = db.model('Test', new Schema({
         date: {type: Date, default: now}
       }));
 
-      const TestDefaults = db.model('TestDefaults');
-
       const post = new TestDefaults;
       assert.ok(post.get('date') instanceof Date);
       assert.equal(+post.get('date'), now);
@@ -1440,14 +1351,12 @@ describe('Model', function() {
     it('nested', function(done) {
       const now = Date.now();
 
-      mongoose.model('TestNestedDefaults', new Schema({
+      const TestDefaults = db.model('Test', new Schema({
         nested: {
           date: {type: Date, default: now}
         }
       }));
 
-      const TestDefaults = db.model('TestNestedDefaults');
-
       const post = new TestDefaults();
       assert.ok(post.get('nested.date') instanceof Date);
       assert.equal(+post.get('nested.date'), now);
@@ -1461,12 +1370,10 @@ describe('Model', function() {
         date: {type: Date, default: now}
       });
 
-      mongoose.model('TestSubdocumentsDefaults', new Schema({
+      const TestSubdocumentsDefaults = db.model('Test', new Schema({
         items: [Items]
       }));
 
-      const TestSubdocumentsDefaults = db.model('TestSubdocumentsDefaults');
-
       const post = new TestSubdocumentsDefaults();
       post.get('items').push({});
       assert.ok(post.get('items')[0].get('date') instanceof Date);
@@ -1475,7 +1382,7 @@ describe('Model', function() {
     });
 
     it('allows nulls', function(done) {
-      const T = db.model('NullDefault', new Schema({name: {type: String, default: null}}), collection);
+      const T = db.model('Test', new Schema({name: {type: String, default: null}}));
       const t = new T();
 
       assert.strictEqual(null, t.name);
@@ -1494,7 +1401,6 @@ describe('Model', function() {
 
   describe('virtuals', function() {
     it('getters', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       const post = new BlogPost({
         title: 'Letters from Earth',
         author: 'Mark Twain'
@@ -1506,7 +1412,6 @@ describe('Model', function() {
     });
 
     it('set()', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       const post = new BlogPost();
 
       post.set('titleWithAuthor', 'Huckleberry Finn by Mark Twain');
@@ -1516,7 +1421,6 @@ describe('Model', function() {
     });
 
     it('should not be saved to the db', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       const post = new BlogPost();
 
       post.set('titleWithAuthor', 'Huckleberry Finn by Mark Twain');
@@ -1554,9 +1458,7 @@ describe('Model', function() {
           this.set('name.last', split[1]);
         });
 
-      mongoose.model('Person', PersonSchema);
-
-      const Person = db.model('Person');
+      const Person = db.model('Person', PersonSchema);
       const person = new Person({
         name: {
           first: 'Michael',
@@ -1579,9 +1481,6 @@ describe('Model', function() {
 
   describe('.remove()', function() {
     it('works', function(done) {
-      const collection = 'blogposts_' + random();
-      const BlogPost = db.model('BlogPost', collection);
-
       BlogPost.create({title: 1}, {title: 2}, function(err) {
         assert.ifError(err);
 
@@ -1599,9 +1498,6 @@ describe('Model', function() {
     });
 
     it('errors when id deselected (gh-3118)', function(done) {
-      const collection = 'blogposts_' + random();
-      const BlogPost = db.model('BlogPost', collection);
-
       BlogPost.create({title: 1}, {title: 2}, function(err) {
         assert.ifError(err);
         BlogPost.findOne({title: 1}, {_id: 0}, function(error, doc) {
@@ -1616,8 +1512,6 @@ describe('Model', function() {
     });
 
     it('should not remove any records when deleting by id undefined', function(done) {
-      const collection = 'blogposts_' + random();
-      const BlogPost = db.model('BlogPost', collection);
       BlogPost.create({title: 1}, {title: 2}, function(err) {
         assert.ifError(err);
 
@@ -1632,9 +1526,6 @@ describe('Model', function() {
     });
 
     it('should not remove all documents in the collection (gh-3326)', function(done) {
-      const collection = 'blogposts_' + random();
-      const BlogPost = db.model('BlogPost', collection);
-
       BlogPost.create({title: 1}, {title: 2}, function(err) {
         assert.ifError(err);
         BlogPost.findOne({title: 1}, function(error, doc) {
@@ -1654,16 +1545,10 @@ describe('Model', function() {
   });
 
   describe('#remove()', function() {
-    let B;
-
-    before(function() {
-      B = db.model('BlogPost', 'blogposts_' + random());
-    });
-
     it('passes the removed document (gh-1419)', function(done) {
-      B.create({}, function(err, post) {
+      BlogPost.create({}, function(err, post) {
         assert.ifError(err);
-        B.findById(post, function(err, found) {
+        BlogPost.findById(post, function(err, found) {
           assert.ifError(err);
 
           found.remove(function(err, doc) {
@@ -1677,9 +1562,9 @@ describe('Model', function() {
     });
 
     it('works as a promise', function(done) {
-      B.create({}, function(err, post) {
+      BlogPost.create({}, function(err, post) {
         assert.ifError(err);
-        B.findById(post, function(err, found) {
+        BlogPost.findById(post, function(err, found) {
           assert.ifError(err);
 
           found.remove().then(function(doc) {
@@ -1701,7 +1586,7 @@ describe('Model', function() {
         return next();
       });
 
-      const RH = db.model('RH', RHS, 'RH_' + random());
+      const RH = db.model('Test', RHS);
 
       RH.create({name: 'to be removed'}, function(err, post) {
         assert.ifError(err);
@@ -1737,7 +1622,7 @@ describe('Model', function() {
         ++docMiddleware;
       });
 
-      const Model = db.model('gh3054', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         const doc = yield Model.create({ name: String });
@@ -1757,8 +1642,6 @@ describe('Model', function() {
 
     describe('when called multiple times', function() {
       it('always executes the passed callback gh-1210', function(done) {
-        const collection = 'blogposts_' + random();
-        const BlogPost = db.model('BlogPost', collection);
         const post = new BlogPost();
 
         post.save(function(err) {
@@ -1791,9 +1674,8 @@ describe('Model', function() {
         subject: {name: String}
       });
 
-      mongoose.model('PostWithClashGetters', Post);
-
-      const PostModel = db.model('PostWithClashGetters', 'postwithclash' + random());
+      db.deleteModel(/BlogPost/);
+      const PostModel = db.model('BlogPost', Post);
 
       const post = new PostModel({
         title: 'Test',
@@ -1823,7 +1705,7 @@ describe('Model', function() {
         }
       });
 
-      const A = mongoose.model('gettersShouldNotBeTriggeredAtConstruction', schema);
+      const A = db.model('Test', schema);
 
       const a = new A({number: 100});
       assert.equal(called, false);
@@ -1844,13 +1726,9 @@ describe('Model', function() {
     });
 
     it('with type defined with { type: Native } (gh-190)', function(done) {
-      const schema = new Schema({
-        date: {type: Date}
-      });
+      const schema = new Schema({ date: {type: Date} });
 
-      mongoose.model('ShortcutGetterObject', schema);
-
-      const ShortcutGetter = db.model('ShortcutGetterObject', 'shortcut' + random());
+      const ShortcutGetter = db.model('Test', schema);
       const post = new ShortcutGetter();
 
       post.set('date', Date.now());
@@ -1865,9 +1743,7 @@ describe('Model', function() {
             second: [Number]
           }
         });
-        mongoose.model('ShortcutGetterNested', schema);
-
-        const ShortcutGetterNested = db.model('ShortcutGetterNested', collection);
+        const ShortcutGetterNested = db.model('Test', schema);
         const doc = new ShortcutGetterNested();
 
         assert.equal(typeof doc.first, 'object');
@@ -1876,8 +1752,6 @@ describe('Model', function() {
       });
 
       it('works with object literals', function(done) {
-        const BlogPost = db.model('BlogPost', collection);
-
         const date = new Date;
 
         const meta = {
@@ -1959,8 +1833,7 @@ describe('Model', function() {
           }
         });
 
-        mongoose.model('NestedStringA', schema);
-        const T = db.model('NestedStringA', collection);
+        const T = db.model('Test', schema);
 
         const t = new T({nest: null});
 
@@ -1982,8 +1855,7 @@ describe('Model', function() {
           }
         });
 
-        mongoose.model('NestedStringB', schema);
-        const T = db.model('NestedStringB', collection);
+        const T = db.model('Test', schema);
 
         const t = new T({nest: undefined});
 
@@ -2006,8 +1878,7 @@ describe('Model', function() {
           }
         });
 
-        mongoose.model('NestedStringC', schema);
-        const T = db.model('NestedStringC', collection);
+        const T = db.model('Test', schema);
 
         const t = new T({nest: null});
 
@@ -2044,13 +1915,11 @@ describe('Model', function() {
       });
 
       it('array of Mixed on existing doc can be pushed to', function(done) {
-        mongoose.model('MySchema', new Schema({
+        const DooDad = db.model('Test', new Schema({
           nested: {
             arrays: []
           }
         }));
-
-        const DooDad = db.model('MySchema');
         const doodad = new DooDad({nested: {arrays: []}});
         const date = 1234567890;
 
@@ -2084,7 +1953,7 @@ describe('Model', function() {
           return [{x: 1}, {x: 2}, {x: 3}];
         }
 
-        mongoose.model('MySchema2', new Schema({
+        const DooDad = db.model('Test', new Schema({
           nested: {
             type: {type: String, default: 'yep'},
             array: {
@@ -2092,8 +1961,6 @@ describe('Model', function() {
             }
           }
         }));
-
-        const DooDad = db.model('MySchema2', collection);
         const doodad = new DooDad();
 
         doodad.save(function(err) {
@@ -2146,8 +2013,8 @@ describe('Model', function() {
         locations: [Location]
       });
 
-      Location = db.model('Location', Location, 'locations_' + random());
-      Deal = db.model('Deal', Deal, 'deals_' + random());
+      Location = db.model('Location', Location);
+      Deal = db.model('Test', Deal);
 
       const location = new Location({lat: 1.2, long: 10});
       assert.equal(location.lat.valueOf(), 1);
@@ -2171,8 +2038,6 @@ describe('Model', function() {
   });
 
   it('changing a number non-atomically (gh-203)', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost();
 
     post.meta.visitors = 5;
@@ -2200,7 +2065,6 @@ describe('Model', function() {
 
   describe('atomic subdocument', function() {
     it('saving', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
       let totalDocs = 4;
       const saveQueue = [];
 
@@ -2287,8 +2151,6 @@ describe('Model', function() {
     });
 
     it('setting (gh-310)', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       BlogPost.create({
         comments: [{title: 'first-title', body: 'first-body'}]
       }, function(err, blog) {
@@ -2326,9 +2188,7 @@ describe('Model', function() {
     let Outer = new Schema({
       inner: [Inner]
     });
-    mongoose.model('Outer', Outer);
-
-    Outer = db.model('Outer', 'arr_test_' + random());
+    Outer = db.model('Test', Outer);
 
     const outer = new Outer();
     outer.inner.push({});
@@ -2362,8 +2222,7 @@ describe('Model', function() {
       }
     });
 
-    mongoose.model('NestedPushes', schema);
-    const Temp = db.model('NestedPushes', collection);
+    const Temp = db.model('Test', schema);
 
     Temp.create({}, function(err, t) {
       assert.ifError(err);
@@ -2391,7 +2250,7 @@ describe('Model', function() {
       }
     });
 
-    const Temp = db.model('NestedPushes', schema, collection);
+    const Temp = db.model('Test', schema);
 
     Temp.create({}, function(err, t) {
       assert.ifError(err);
@@ -2418,7 +2277,7 @@ describe('Model', function() {
       }
     });
 
-    const Temp = db.model('NestedPushes', schema, collection);
+    const Temp = db.model('Test', schema);
 
     Temp.create({nested: {nums: [1, 2, 3, 4, 5]}}, function(err, t) {
       assert.ifError(err);
@@ -2437,7 +2296,7 @@ describe('Model', function() {
       }
     });
 
-    const Temp = db.model('NestedPushes', schema, collection);
+    const Temp = db.model('Test', schema);
 
     const p1 = Temp.create({nested: {nums: [1, 2, 3, 4, 5]}});
     p1.then(function(t) {
@@ -2455,7 +2314,7 @@ describe('Model', function() {
       }
     });
 
-    const Temp = db.model('NestedPushes', schema, collection);
+    const Temp = db.model('Test', schema);
 
     Temp.create({nested: {nums: [1, 2, 3, 4, 5]}}, function(err, t) {
       assert.ifError(err);
@@ -2472,8 +2331,7 @@ describe('Model', function() {
       }
     });
 
-    mongoose.model('TestingShift', schema);
-    const Temp = db.model('TestingShift', collection);
+    const Temp = db.model('Test', schema);
 
     Temp.create({nested: {nums: [1, 2, 3]}}, function(err, t) {
       assert.ifError(err);
@@ -2520,8 +2378,7 @@ describe('Model', function() {
       let totalDocs = 2;
       const saveQueue = [];
 
-      mongoose.model('Temp', TempSchema);
-      const Temp = db.model('Temp', collection);
+      const Temp = db.model('Test', TempSchema);
 
       const t = new Temp();
 
@@ -2584,8 +2441,7 @@ describe('Model', function() {
       let totalDocs = 2;
       const saveQueue = [];
 
-      mongoose.model('StrList', StrListSchema);
-      const StrList = db.model('StrList');
+      const StrList = db.model('Test', StrListSchema);
 
       const t = new StrList();
 
@@ -2649,8 +2505,7 @@ describe('Model', function() {
       let totalDocs = 2;
       const saveQueue = [];
 
-      mongoose.model('BufList', BufListSchema);
-      const BufList = db.model('BufList');
+      const BufList = db.model('Test', BufListSchema);
 
       const t = new BufList();
 
@@ -2709,7 +2564,7 @@ describe('Model', function() {
     });
 
     it('works with modified element properties + doc removal (gh-975)', function(done) {
-      const B = db.model('BlogPost', collection);
+      const B = BlogPost;
       const b = new B({comments: [{title: 'gh-975'}]});
 
       b.save(function(err) {
@@ -2742,8 +2597,6 @@ describe('Model', function() {
     });
 
     it('updating an embedded document in an embedded array with set call', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       BlogPost.create({
         comments: [{
           title: 'before-change'
@@ -2773,8 +2626,6 @@ describe('Model', function() {
   });
 
   it('updating an embedded document in an embedded array (gh-255)', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     BlogPost.create({comments: [{title: 'woot'}]}, function(err, post) {
       assert.ifError(err);
       BlogPost.findById(post._id, function(err, found) {
@@ -2800,8 +2651,7 @@ describe('Model', function() {
     });
     const GH334Schema = new Schema({name: String, arrData: [SubSchema]});
 
-    mongoose.model('GH334', GH334Schema);
-    const AModel = db.model('GH334');
+    const AModel = db.model('Test', GH334Schema);
     const instance = new AModel();
 
     instance.set({name: 'name-value', arrData: [{name: 'arrName1', subObj: {subName: 'subName1'}}]});
@@ -2823,7 +2673,6 @@ describe('Model', function() {
   });
 
   it('saving an embedded document twice should not push that doc onto the parent doc twice (gh-267)', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
     const post = new BlogPost();
 
     post.comments.push({title: 'woot'});
@@ -2848,8 +2697,6 @@ describe('Model', function() {
 
   describe('embedded array filtering', function() {
     it('by the id shortcut function', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost();
 
       post.comments.push({title: 'woot'});
@@ -2876,8 +2723,6 @@ describe('Model', function() {
     });
 
     it('by the id with cast error', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost();
 
       post.save(function(err) {
@@ -2892,8 +2737,6 @@ describe('Model', function() {
     });
 
     it('by the id shortcut with no match', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost();
 
       post.save(function(err) {
@@ -2909,8 +2752,6 @@ describe('Model', function() {
   });
 
   it('removing a subdocument atomically', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost();
     post.title = 'hahaha';
     post.comments.push({title: 'woot'});
@@ -2938,8 +2779,6 @@ describe('Model', function() {
   });
 
   it('single pull embedded doc', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost();
     post.title = 'hahaha';
     post.comments.push({title: 'woot'});
@@ -2967,7 +2806,6 @@ describe('Model', function() {
   });
 
   it('saving mixed data', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
     let count = 3;
 
     // string
@@ -3046,8 +2884,6 @@ describe('Model', function() {
   });
 
   it('populating mixed data from the constructor (gh-200)', function(done) {
-    const BlogPost = db.model('BlogPost');
-
     const post = new BlogPost({
       mixed: {
         type: 'test',
@@ -3069,14 +2905,17 @@ describe('Model', function() {
       type: {type: String, default: 'YES!'}
     }));
 
-    const TestDefaults = db.model('TestTypeDefaults');
+    const TestDefaults = db.model('Test', new Schema({
+      type: {type: String, default: 'YES!'}
+    }));
 
     let post = new TestDefaults();
     assert.equal(typeof post.get('type'), 'string');
     assert.equal(post.get('type'), 'YES!');
 
     // GH-402
-    const TestDefaults2 = db.model('TestTypeDefaults2', new Schema({
+    db.deleteModel('Test');
+    const TestDefaults2 = db.model('Test', new Schema({
       x: {y: {type: {type: String}, owner: String}}
     }));
 
@@ -3090,8 +2929,6 @@ describe('Model', function() {
   });
 
   it('unaltered model does not clear the doc (gh-195)', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost();
     post.title = 'woot';
     post.save(function(err) {
@@ -3130,7 +2967,7 @@ describe('Model', function() {
           next(null);
         });
 
-        const S = db.model('S', schema, collection);
+        const S = db.model('Test', schema);
         const s = new S({name: 'zupa'});
 
         s.save(function(err) {
@@ -3158,7 +2995,7 @@ describe('Model', function() {
           return next();
         });
 
-        const S = db.model('S', schema, collection);
+        const S = db.model('Test', schema);
         const s = new S({name: 'zupa'});
 
         const p = s.save();
@@ -3189,7 +3026,7 @@ describe('Model', function() {
           next();
         });
 
-        const S = db.model('presave_hook', schema, 'presave_hook');
+        const S = db.model('Test', schema);
         const s = new S({name: 'a', child: [{name: 'b', grand: [{name: 'c'}]}]});
 
         s.save(function(err, doc) {
@@ -3220,7 +3057,7 @@ describe('Model', function() {
           next();
         });
 
-        const S = db.model('presave_hook_error', schema, 'presave_hook_error');
+        const S = db.model('Test', schema);
         const s = new S({name: 'a', child: [{name: 'b', grand: [{name: 'c'}]}]});
 
         s.save(function(err) {
@@ -3239,7 +3076,7 @@ describe('Model', function() {
             preId = this._id;
           });
 
-          const PreInit = db.model('PreInit', PreInitSchema, 'pre_inits' + random());
+          const PreInit = db.model('Test', PreInitSchema);
 
           const doc = new PreInit();
           doc.save(function(err) {
@@ -3278,9 +3115,7 @@ describe('Model', function() {
           remove = true;
         });
 
-        mongoose.model('PostHookTest', schema);
-
-        const BlogPost = db.model('PostHookTest');
+        const BlogPost = db.model('Test', schema);
 
         post = new BlogPost();
 
@@ -3321,9 +3156,7 @@ describe('Model', function() {
           embeds: [EmbeddedSchema]
         });
 
-        db.model('Parent', ParentSchema);
-
-        const Parent = db.model('Parent');
+        const Parent = db.model('Parent', ParentSchema);
 
         const parent = new Parent();
 
@@ -3340,8 +3173,6 @@ describe('Model', function() {
 
   describe('#exec()', function() {
     it.skip('count()', function(done) {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
       BlogPost.create({title: 'interoperable count as promise'}, function(err) {
         assert.ifError(err);
         const query = BlogPost.count({title: 'interoperable count as promise'});
@@ -3354,8 +3185,6 @@ describe('Model', function() {
     });
 
     it('countDocuments()', function() {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
       return BlogPost.create({ title: 'foo' }).
         then(() => BlogPost.countDocuments({ title: 'foo' }).exec()).
         then(count => {
@@ -3364,8 +3193,6 @@ describe('Model', function() {
     });
 
     it('estimatedDocumentCount()', function() {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
       return BlogPost.create({ title: 'foo' }).
         then(() => BlogPost.estimatedDocumentCount({ title: 'foo' }).exec()).
         then(count => {
@@ -3374,9 +3201,6 @@ describe('Model', function() {
     });
 
     it('update()', function(done) {
-      const col = 'BlogPost' + random();
-      const BlogPost = db.model(col, bpSchema);
-
       BlogPost.create({title: 'interoperable update as promise'}, function(err) {
         assert.ifError(err);
         const query = BlogPost.update({title: 'interoperable update as promise'}, {title: 'interoperable update as promise delta'});
@@ -3394,8 +3218,6 @@ describe('Model', function() {
     });
 
     it('findOne()', function(done) {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
       BlogPost.create({title: 'interoperable findOne as promise'}, function(err, created) {
         assert.ifError(err);
         const query = BlogPost.findOne({title: 'interoperable findOne as promise'});
@@ -3408,8 +3230,6 @@ describe('Model', function() {
     });
 
     it('find()', function(done) {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
       BlogPost.create(
         {title: 'interoperable find as promise'},
         {title: 'interoperable find as promise'},
@@ -3430,8 +3250,6 @@ describe('Model', function() {
     });
 
     it.skip('remove()', function(done) {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
       BlogPost.create(
         {title: 'interoperable remove as promise'},
         function(err) {
@@ -3448,7 +3266,6 @@ describe('Model', function() {
     });
 
     it('op can be changed', function(done) {
-      const BlogPost = db.model('BlogPost' + random(), bpSchema);
       const title = 'interop ad-hoc as promise';
 
       BlogPost.create({title: title}, function(err, created) {
@@ -3464,8 +3281,6 @@ describe('Model', function() {
 
     describe('promises', function() {
       it.skip('count()', function(done) {
-        const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
         BlogPost.create({title: 'interoperable count as promise 2'}, function(err) {
           assert.ifError(err);
           const query = BlogPost.count({title: 'interoperable count as promise 2'});
@@ -3478,9 +3293,6 @@ describe('Model', function() {
       });
 
       it.skip('update()', function(done) {
-        const col = 'BlogPost' + random();
-        const BlogPost = db.model(col, bpSchema);
-
         BlogPost.create({title: 'interoperable update as promise 2'}, function(err) {
           assert.ifError(err);
           const query = BlogPost.update({title: 'interoperable update as promise 2'}, {title: 'interoperable update as promise delta 2'});
@@ -3496,8 +3308,6 @@ describe('Model', function() {
       });
 
       it('findOne()', function() {
-        const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
         let created;
         return BlogPost.create({title: 'interoperable findOne as promise 2'}).
           then(doc => {
@@ -3512,8 +3322,6 @@ describe('Model', function() {
       });
 
       it('find()', function(done) {
-        const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
         BlogPost.create(
           {title: 'interoperable find as promise 2'},
           {title: 'interoperable find as promise 2'},
@@ -3532,8 +3340,6 @@ describe('Model', function() {
       });
 
       it.skip('remove()', function() {
-        const BlogPost = db.model('BlogPost' + random(), bpSchema);
-
         return BlogPost.create({title: 'interoperable remove as promise 2'}).
           then(() => {
             return BlogPost.remove({title: 'interoperable remove as promise 2'});
@@ -3547,11 +3353,9 @@ describe('Model', function() {
       });
 
       it('are thenable', function(done) {
-        const B = db.model('BlogPost' + random(), bpSchema);
-
         const peopleSchema = new Schema({name: String, likes: ['ObjectId']});
-        const P = db.model('promise-BP-people', peopleSchema, random());
-        B.create(
+        const P = db.model('Test', peopleSchema);
+        BlogPost.create(
           {title: 'then promise 1'},
           {title: 'then promise 2'},
           {title: 'then promise 3'},
@@ -3565,7 +3369,7 @@ describe('Model', function() {
               function(err) {
                 assert.ifError(err);
 
-                const promise = B.find({title: /^then promise/}).select('_id').exec();
+                const promise = BlogPost.find({title: /^then promise/}).select('_id').exec();
                 promise.then(function(blogs) {
                   const ids = blogs.map(function(m) {
                     return m._id;
@@ -3587,8 +3391,6 @@ describe('Model', function() {
 
   describe('console.log', function() {
     it('hides private props', function(done) {
-      const BlogPost = db.model('BlogPost', collection);
-
       const date = new Date(1305730951086);
       const id0 = new DocumentObjectId('4dd3e169dbfb13b4570000b9');
       const id1 = new DocumentObjectId('4dd3e169dbfb13b4570000b6');
@@ -3618,7 +3420,7 @@ describe('Model', function() {
 
   describe('pathnames', function() {
     it('named path can be used', function(done) {
-      const P = db.model('pathnametest', new Schema({path: String}));
+      const P = db.model('Test', new Schema({path: String}));
 
       let threw = false;
       try {
@@ -3634,7 +3436,7 @@ describe('Model', function() {
 
   it('subdocuments with changed values should persist the values', function(done) {
     const Subdoc = new Schema({name: String, mixed: Schema.Types.Mixed});
-    const T = db.model('SubDocMixed', new Schema({subs: [Subdoc]}));
+    const T = db.model('Test', new Schema({subs: [Subdoc]}));
 
     const t = new T({subs: [{name: 'Hubot', mixed: {w: 1, x: 2}}]});
     assert.equal(t.subs[0].name, 'Hubot');
@@ -3689,16 +3491,12 @@ describe('Model', function() {
 
   describe('RegExps', function() {
     it('can be saved', function(done) {
-      const db = start();
-      const BlogPost = db.model('BlogPost', collection);
-
       const post = new BlogPost({mixed: {rgx: /^asdf$/}});
       assert.ok(post.mixed.rgx instanceof RegExp);
       assert.equal(post.mixed.rgx.source, '^asdf$');
       post.save(function(err) {
         assert.ifError(err);
         BlogPost.findById(post._id, function(err, post) {
-          db.close();
           assert.ifError(err);
           assert.ok(post.mixed.rgx instanceof RegExp);
           assert.equal(post.mixed.rgx.source, '^asdf$');
@@ -3710,8 +3508,6 @@ describe('Model', function() {
 
   // Demonstration showing why GH-261 is a misunderstanding
   it('a single instantiated document should be able to update its embedded documents more than once', function(done) {
-    const BlogPost = db.model('BlogPost', collection);
-
     const post = new BlogPost();
     post.comments.push({title: 'one'});
     post.save(function(err) {
@@ -3738,7 +3534,7 @@ describe('Model', function() {
           next(new Error);
         });
 
-        const DefaultErr = db.model('DefaultErr3', DefaultErrSchema, 'default_err_' + random());
+        const DefaultErr = db.model('Test', DefaultErrSchema);
 
         DefaultErr.on('error', function(err) {
           assert.ok(err instanceof Error);
@@ -3750,9 +3546,7 @@ describe('Model', function() {
     });
 
     it('saved changes made within callback of a previous no-op save gh-1139', function(done) {
-      const B = db.model('BlogPost', collection);
-
-      const post = new B({title: 'first'});
+      const post = new BlogPost({title: 'first'});
       post.save(function(err) {
         assert.ifError(err);
 
@@ -3764,7 +3558,7 @@ describe('Model', function() {
           post.save(function(err) {
             assert.ifError(err);
 
-            B.findById(post, function(err, doc) {
+            BlogPost.findById(post, function(err, doc) {
               assert.ifError(err);
               assert.equal(doc.title, 'changed');
               done();
@@ -3776,7 +3570,7 @@ describe('Model', function() {
 
     it('rejects new documents that have no _id set (1595)', function(done) {
       const s = new Schema({_id: {type: String}});
-      const B = db.model('1595', s);
+      const B = db.model('Test', s);
       const b = new B;
       b.save(function(err) {
         assert.ok(err);
@@ -3786,7 +3580,7 @@ describe('Model', function() {
     });
 
     it('no TypeError when attempting to save more than once after using atomics', function(done) {
-      const M = db.model('M', new Schema({
+      const M = db.model('Test', new Schema({
         test: {type: 'string', unique: true},
         elements: [{
           el: {type: 'string', required: true}
@@ -3800,17 +3594,19 @@ describe('Model', function() {
         test: 'b',
         elements: [{el: 'c'}]
       });
-      a.save(function() {
-        b.save(function() {
-          b.elements.push({el: 'd'});
-          b.test = 'a';
-          b.save(function(error,res) {
-            assert.strictEqual(!error,false);
-            assert.strictEqual(res,undefined);
+      M.init(function() {
+        a.save(function() {
+          b.save(function() {
+            b.elements.push({el: 'd'});
+            b.test = 'a';
             b.save(function(error,res) {
-              assert.strictEqual(!error,false);
+              assert.ok(error);
               assert.strictEqual(res,undefined);
-              done();
+              b.save(function(error,res) {
+                assert.ok(error);
+                assert.strictEqual(res,undefined);
+                M.collection.drop(done);
+              });
             });
           });
         });
@@ -3818,7 +3614,7 @@ describe('Model', function() {
     });
     it('should clear $versionError and saveOptions after saved (gh-8040)', function(done) {
       const schema = new Schema({name: String});
-      const Model = db.model('gh8040', schema);
+      const Model = db.model('Test', schema);
       const doc = new Model({
         name: 'Fonger'
       });
@@ -3838,11 +3634,9 @@ describe('Model', function() {
 
   describe('_delta()', function() {
     it('should overwrite arrays when directly set (gh-1126)', function(done) {
-      const B = db.model('BlogPost', collection);
-
-      B.create({title: 'gh-1126', numbers: [1, 2]}, function(err, b) {
+      BlogPost.create({title: 'gh-1126', numbers: [1, 2]}, function(err, b) {
         assert.ifError(err);
-        B.findById(b._id, function(err, b) {
+        BlogPost.findById(b._id, function(err, b) {
           assert.ifError(err);
           assert.deepEqual([1, 2].join(), b.numbers.join());
 
@@ -3858,7 +3652,7 @@ describe('Model', function() {
           b.save(function(err) {
             assert.ifError(err);
 
-            B.findById(b._id, function(err, b) {
+            BlogPost.findById(b._id, function(err, b) {
               assert.ifError(err);
               assert.ok(Array.isArray(b.numbers));
               assert.equal(b.numbers.length, 1);
@@ -3872,7 +3666,7 @@ describe('Model', function() {
               b.numbers.push(5);
               b.save(function(err) {
                 assert.ifError(err);
-                B.findById(b._id, function(err, b) {
+                BlogPost.findById(b._id, function(err, b) {
                   assert.ifError(err);
                   assert.ok(Array.isArray(b.numbers));
                   assert.equal(b.numbers.length, 2);
@@ -3888,8 +3682,7 @@ describe('Model', function() {
     });
 
     it('should use $set when subdoc changed before pulling (gh-1303)', function(done) {
-      const B = db.model('BlogPost', 'gh-1303-' + random());
-
+      const B = BlogPost;
       B.create(
         {title: 'gh-1303', comments: [{body: 'a'}, {body: 'b'}, {body: 'c'}]},
         function(err, b) {
@@ -3928,7 +3721,7 @@ describe('Model', function() {
 
   describe('backward compatibility', function() {
     it('with conflicted data in db', function(done) {
-      const M = db.model('backwardDataConflict', new Schema({namey: {first: String, last: String}}));
+      const M = db.model('Test', new Schema({namey: {first: String, last: String}}));
       const m = new M({namey: '[object Object]'});
       m.namey = {first: 'GI', last: 'Joe'};// <-- should overwrite the string
       m.save(function(err) {
@@ -3942,7 +3735,7 @@ describe('Model', function() {
     it('with positional notation on path not existing in schema (gh-1048)', function(done) {
       const db = start();
 
-      const M = db.model('backwardCompat-gh-1048', Schema({name: 'string'}));
+      const M = db.model('Test', Schema({name: 'string'}));
       db.on('open', function() {
         const o = {
           name: 'gh-1048',
@@ -3972,7 +3765,7 @@ describe('Model', function() {
 
   describe('non-schema adhoc property assignments', function() {
     it('are not saved', function(done) {
-      const B = db.model('BlogPost', collection);
+      const B = BlogPost;
 
       const b = new B;
       b.whateveriwant = 10;
@@ -3989,7 +3782,7 @@ describe('Model', function() {
 
   it('should not throw range error when using Number _id and saving existing doc (gh-691)', function(done) {
     const T = new Schema({_id: Number, a: String});
-    const D = db.model('Testing691', T, 'asdf' + random());
+    const D = db.model('Test', T);
     const d = new D({_id: 1});
     d.save(function(err) {
       assert.ifError(err);
@@ -4008,7 +3801,7 @@ describe('Model', function() {
 
   describe('setting an unset value', function() {
     it('is saved (gh-742)', function(done) {
-      const DefaultTestObject = db.model('defaultTestObject',
+      const DefaultTestObject = db.model('Test',
         new Schema({
           score: {type: Number, default: 55}
         })
@@ -4045,7 +3838,7 @@ describe('Model', function() {
 
   it('path is cast to correct value when retreived from db', function(done) {
     const schema = new Schema({title: {type: 'string', index: true}});
-    const T = db.model('T', schema);
+    const T = db.model('Test', schema);
     T.collection.insertOne({title: 234}, {safe: true}, function(err) {
       assert.ifError(err);
       T.findOne(function(err, doc) {
@@ -4057,8 +3850,7 @@ describe('Model', function() {
   });
 
   it('setting a path to undefined should retain the value as undefined', function(done) {
-    const B = db.model('BlogPost', collection + random());
-
+    const B = BlogPost;
     const doc = new B;
     doc.title = 'css3';
     assert.equal(doc.$__delta()[1].$set.title, 'css3');
@@ -4126,7 +3918,7 @@ describe('Model', function() {
 
   describe('unsetting a default value', function() {
     it('should be ignored (gh-758)', function(done) {
-      const M = db.model('758', new Schema({s: String, n: Number, a: Array}));
+      const M = db.model('Test', new Schema({s: String, n: Number, a: Array}));
       M.collection.insertOne({}, {safe: true}, function(err) {
         assert.ifError(err);
         M.findOne(function(err, m) {
@@ -4142,15 +3934,15 @@ describe('Model', function() {
   it('allow for object passing to ref paths (gh-1606)', function(done) {
     const schA = new Schema({title: String});
     const schma = new Schema({
-      thing: {type: Schema.Types.ObjectId, ref: 'A'},
+      thing: {type: Schema.Types.ObjectId, ref: 'Test'},
       subdoc: {
         some: String,
-        thing: [{type: Schema.Types.ObjectId, ref: 'A'}]
+        thing: [{type: Schema.Types.ObjectId, ref: 'Test'}]
       }
     });
 
-    const M1 = db.model('A', schA);
-    const M2 = db.model('A2', schma);
+    const M1 = db.model('Test', schA);
+    const M2 = db.model('Test1', schma);
     const a = new M1({title: 'hihihih'}).toObject();
     const thing = new M2({
       thing: a,
@@ -4179,7 +3971,7 @@ describe('Model', function() {
       }
     });
 
-    const Order = db.model('order' + random(), OrderSchema);
+    const Order = db.model('Test', OrderSchema);
     const o = new Order({total: null});
 
     assert.deepEqual(calls, [0, null]);
@@ -4188,15 +3980,9 @@ describe('Model', function() {
   });
 
   describe('Skip setting default value for Geospatial-indexed fields (gh-1668)', function() {
-    let db;
+    beforeEach(() => db.deleteModel(/Person/));
 
-    before(function() {
-      db = start({ noErrorListener: true });
-    });
-
-    after(function(done) {
-      db.close(done);
-    });
+    this.timeout(5000);
 
     it('2dsphere indexed field with value is saved', function() {
       const PersonSchema = new Schema({
@@ -4205,9 +3991,9 @@ describe('Model', function() {
           type: [Number],
           index: '2dsphere'
         }
-      });
+      }, { autoIndex: false });
 
-      const Person = db.model('Person_1', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const loc = [0.3, 51.4];
       const p = new Person({
         name: 'Jimmy Page',
@@ -4215,7 +4001,7 @@ describe('Model', function() {
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4233,15 +4019,15 @@ describe('Model', function() {
           type: [Number],
           index: '2dsphere'
         }
-      });
+      }, { autoIndex: false });
 
-      const Person = db.model('Person_2', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page'
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4261,11 +4047,11 @@ describe('Model', function() {
             type: [Number]
           }
         }
-      });
+      }, { autoIndex: false });
 
       PersonSchema.index({'nested.loc': '2dsphere'});
 
-      const Person = db.model('Person_3', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page'
       });
@@ -4273,7 +4059,8 @@ describe('Model', function() {
       p.nested.tag = 'guitarist';
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4292,14 +4079,15 @@ describe('Model', function() {
           type: { type: String, enum: ['Point'] },
           coordinates: [Number]
         }
-      });
+      }, { autoIndex: false });
 
       LocationSchema.index({ 'location': '2dsphere' });
 
-      const Location = db.model('gh3233', LocationSchema);
+      const Location = db.model('Test', LocationSchema);
 
       return co(function*() {
-        yield Location.init();
+        yield Location.collection.drop();
+        yield Location.createIndexes();
 
         yield Location.create({
           name: 'Undefined location'
@@ -4314,15 +4102,16 @@ describe('Model', function() {
           type: [Number],
           index: '2dsphere'
         }
-      });
+      }, { autoIndex: false });
 
-      const Person = db.model('Person_4', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page'
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4347,15 +4136,16 @@ describe('Model', function() {
           required: true,
           index: '2dsphere'
         }
-      });
+      }, { autoIndex: false });
 
-      const Person = db.model('Person_5', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page'
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         let err;
         yield p.save().catch(_err => { err = _err; });
@@ -4374,15 +4164,16 @@ describe('Model', function() {
           default: loc,
           index: '2dsphere'
         }
-      });
+      }, { autoIndex: false });
 
-      const Person = db.model('Person_6', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page'
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4400,15 +4191,16 @@ describe('Model', function() {
           type: [Number],
           index: '2d'
         }
-      });
+      }, { autoIndex: false });
 
-      const Person = db.model('Person_7', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page'
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4418,18 +4210,18 @@ describe('Model', function() {
       });
     });
 
-    it('Compound index with 2dsphere field without value is saved', function() {
+    it.skip('Compound index with 2dsphere field without value is saved', function() {
       const PersonSchema = new Schema({
         name: String,
         type: String,
         slug: {type: String, index: {unique: true}},
         loc: {type: [Number]},
         tags: {type: [String], index: true}
-      });
+      }, { autoIndex: false });
 
       PersonSchema.index({name: 1, loc: '2dsphere'});
 
-      const Person = db.model('Person_8', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page',
         type: 'musician',
@@ -4438,7 +4230,8 @@ describe('Model', function() {
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4446,22 +4239,24 @@ describe('Model', function() {
 
         assert.equal(personDoc.name, 'Jimmy Page');
         assert.equal(personDoc.loc, undefined);
+
+        yield Person.collection.drop();
       });
     });
 
-    it('Compound index on field earlier declared with 2dsphere index is saved', function() {
+    it.skip('Compound index on field earlier declared with 2dsphere index is saved', function() {
       const PersonSchema = new Schema({
         name: String,
         type: String,
         slug: {type: String, index: {unique: true}},
         loc: {type: [Number]},
         tags: {type: [String], index: true}
-      });
+      }, { autoIndex: false });
 
       PersonSchema.index({loc: '2dsphere'});
       PersonSchema.index({name: 1, loc: -1});
 
-      const Person = db.model('Person_9', PersonSchema);
+      const Person = db.model('Person', PersonSchema);
       const p = new Person({
         name: 'Jimmy Page',
         type: 'musician',
@@ -4470,7 +4265,8 @@ describe('Model', function() {
       });
 
       return co(function*() {
-        yield Person.init();
+        yield Person.collection.drop();
+        yield Person.createIndexes();
 
         yield p.save();
 
@@ -4478,6 +4274,8 @@ describe('Model', function() {
 
         assert.equal(personDoc.name, 'Jimmy Page');
         assert.equal(personDoc.loc, undefined);
+
+        yield Person.collection.drop();
       });
     });
   });
@@ -4485,7 +4283,7 @@ describe('Model', function() {
   it('save max bson size error with buffering (gh-3906)', function(done) {
     this.timeout(10000);
     const db = start({ noErrorListener: true });
-    const Test = db.model('gh3906_0', { name: Object });
+    const Test = db.model('Test', { name: Object });
 
     const test = new Test({
       name: {
@@ -4503,7 +4301,7 @@ describe('Model', function() {
   it('reports max bson size error in save (gh-3906)', function(done) {
     this.timeout(10000);
     const db = start({ noErrorListener: true });
-    const Test = db.model('gh3906', { name: Object });
+    const Test = db.model('Test', { name: Object });
 
     const test = new Test({
       name: {
@@ -4521,16 +4319,6 @@ describe('Model', function() {
   });
 
   describe('bug fixes', function() {
-    let db;
-
-    before(function() {
-      db = start({ noErrorListener: true });
-    });
-
-    after(function(done) {
-      db.close(done);
-    });
-
     it('doesnt crash (gh-1920)', function(done) {
       const parentSchema = new Schema({
         children: [new Schema({
@@ -4538,7 +4326,7 @@ describe('Model', function() {
         })]
       });
 
-      const Parent = db.model('gh-1920', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const parent = new Parent();
       parent.children.push({name: 'child name'});
@@ -4561,7 +4349,7 @@ describe('Model', function() {
         }
       });
 
-      const Unique = db.model('Unique', UniqueSchema);
+      const Unique = db.model('Test', UniqueSchema);
 
       const u1 = new Unique({
         changer: 'a',
@@ -4586,7 +4374,7 @@ describe('Model', function() {
             u2.save(function(err) {
               assert.ok(err);
               assert.ok(u2.isModified('changer'));
-              done();
+              Unique.collection.drop(done);
             });
           });
         });
@@ -4597,7 +4385,7 @@ describe('Model', function() {
       const schema = new Schema({
         name: String
       }, { timestamps: true });
-      const Movie = db.model('gh723', schema);
+      const Movie = db.model('Movie', schema);
 
       const arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
       Movie.insertMany(arr, function(error, docs) {
@@ -4638,7 +4426,7 @@ describe('Model', function() {
         const schema = new Schema({
           name: { type: String, unique: true }
         });
-        const Movie = db.model('gh3893', schema);
+        const Movie = db.model('Movie', schema);
 
         const arr = [
           { name: 'Star Wars' },
@@ -4654,7 +4442,7 @@ describe('Model', function() {
               assert.equal(docs.length, 2);
               assert.equal(docs[0].name, 'Star Wars');
               assert.equal(docs[1].name, 'The Empire Strikes Back');
-              done();
+              Movie.collection.drop(done);
             });
           });
         });
@@ -4669,7 +4457,9 @@ describe('Model', function() {
       const arrGh8234 = [{ name: 'Rigas' }, { name: 'Tonis', age: 9 }];
       let Gh8234;
       before('init model', () => {
-        Gh8234 = db.model('gh8234', gh8234Schema);
+        Gh8234 = db.model('Test', gh8234Schema);
+
+        return Gh8234.deleteMany({});
       });
       afterEach('delete inserted data', function() {
         return Gh8234.deleteMany({});
@@ -4727,7 +4517,7 @@ describe('Model', function() {
         const schema = new Schema({
           name: { type: String, required: true }
         });
-        const Movie = db.model('gh5068', schema);
+        const Movie = db.model('Movie', schema);
 
         const arr = [
           { name: 'Star Wars' },
@@ -4766,7 +4556,7 @@ describe('Model', function() {
         const schema = new Schema({
           name: { type: String, required: true }
         });
-        const Movie = db.model('gh5068-2', schema);
+        const Movie = db.model('Movie', schema);
 
         const arr = [
           { foo: 'Star Wars' },
@@ -4804,7 +4594,7 @@ describe('Model', function() {
       schema.post('insertMany', function() {
         ++calledPost;
       });
-      const Movie = db.model('gh3846', schema);
+      const Movie = db.model('Movie', schema);
 
       const arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
       Movie.insertMany(arr, function(error, docs) {
@@ -4823,7 +4613,7 @@ describe('Model', function() {
 
     it('insertMany() with timestamps (gh-723)', function() {
       const schema = new Schema({ name: String }, { timestamps: true });
-      const Movie = db.model('gh723_0', schema);
+      const Movie = db.model('Movie', schema);
       const start = Date.now();
 
       const arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
@@ -4844,7 +4634,7 @@ describe('Model', function() {
     });
 
     it('returns empty array if no documents (gh-8130)', function() {
-      const Movie = db.model('gh8130', Schema({ name: String }));
+      const Movie = db.model('Movie', Schema({ name: String }));
       return Movie.insertMany([]).then(docs => assert.deepEqual(docs, []));
     });
 
@@ -4852,7 +4642,7 @@ describe('Model', function() {
       const schema = new Schema({
         name: { type: String, required: true }
       });
-      const Movie = db.model('gh5337', schema);
+      const Movie = db.model('Movie', schema);
 
       const arr = [
         { foo: 'The Phantom Menace' },
@@ -4882,8 +4672,8 @@ describe('Model', function() {
         }
       });
 
-      const Person = db.model('gh4590', personSchema);
-      const Movie = db.model('gh4590_0', movieSchema);
+      const Person = db.model('Person', personSchema);
+      const Movie = db.model('Movie', movieSchema);
 
       const arnold = new Person({ name: 'Arnold Schwarzenegger' });
       const movies = [{ name: 'Predator', leadActor: arnold }];
@@ -4902,7 +4692,7 @@ describe('Model', function() {
       const schema = new Schema({
         name: String
       });
-      const Movie = db.model('gh4237', schema);
+      const Movie = db.model('Movie', schema);
 
       const arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
       Movie.insertMany(arr).then(function(docs) {
@@ -4920,7 +4710,7 @@ describe('Model', function() {
     it('insertMany() with error handlers (gh-6228)', function() {
       const schema = new Schema({
         name: { type: String, unique: true }
-      });
+      }, { autoIndex: false });
 
       let postCalled = 0;
       let postErrorCalled = 0;
@@ -4934,10 +4724,10 @@ describe('Model', function() {
         next(err);
       });
 
-      const Movie = db.model('gh6228', schema);
+      const Movie = db.model('Movie', schema);
 
       return co(function*() {
-        yield Movie.init();
+        yield Movie.createIndexes();
 
         let threw = false;
         try {
@@ -4953,6 +4743,8 @@ describe('Model', function() {
         assert.ok(threw);
         assert.equal(postCalled, 0);
         assert.equal(postErrorCalled, 1);
+
+        yield Movie.collection.drop();
       });
     });
 
@@ -4961,7 +4753,7 @@ describe('Model', function() {
         _id: mongoose.Schema.Types.ObjectId,
         url: { type: String }
       });
-      const Image = db.model('gh8363', schema);
+      const Image = db.model('Test', schema);
       Image.insertMany(['a', 'b', 'c']).catch((error) => {
         assert.equal(error.name, 'ObjectParameterError');
         done();
@@ -4973,7 +4765,7 @@ describe('Model', function() {
         name: { type: String }
       });
 
-      const Food = db.model('gh7852', schema);
+      const Food = db.model('Test', schema);
 
       return co(function*() {
         const foods = yield Food.insertMany([
@@ -4989,7 +4781,7 @@ describe('Model', function() {
       const schema = new Schema({
         name: String
       });
-      const Character = db.model('gh7857', schema);
+      const Character = db.model('Test', schema);
 
       const arr = [
         { name: 'Tyrion Lannister' },
@@ -5015,7 +4807,7 @@ describe('Model', function() {
       const schema = new Schema({
         name: String
       });
-      const Character = db.model('gh6805', schema);
+      const Character = db.model('Test', schema);
 
       const arr = [
         { name: 'Tyrion Lannister' },
@@ -5044,7 +4836,7 @@ describe('Model', function() {
           type: [{ name: String, character: String }],
           default: function() {
             // `this` should be root document and has initial data
-            if (this.title === 'Passenger') {
+            if (this.title === 'Passengers') {
               return [
                 { name: 'Jennifer Lawrence', character: 'Aurora Lane' },
                 { name: 'Chris Pratt', character: 'Jim Preston' }
@@ -5055,8 +4847,8 @@ describe('Model', function() {
         }
       });
 
-      const Movie = db.model('gh6840', schema);
-      const movie = new Movie({ title: 'Passenger'});
+      const Movie = db.model('Movie', schema);
+      const movie = new Movie({ title: 'Passengers'});
       assert.equal(movie.actors.length, 2);
     });
 
@@ -5078,7 +4870,7 @@ describe('Model', function() {
 
       it('arrayFilter (gh-5965)', function() {
         return co(function*() {
-          const MyModel = db.model('gh5965', new Schema({
+          const MyModel = db.model('Test', new Schema({
             _id: Number,
             grades: [Number]
           }));
@@ -5102,7 +4894,7 @@ describe('Model', function() {
 
       it('arrayFilter casting (gh-5965) (gh-7079)', function() {
         return co(function*() {
-          const MyModel = db.model('gh7079', new Schema({
+          const MyModel = db.model('Test', new Schema({
             _id: Number,
             grades: [Number]
           }));
@@ -5135,7 +4927,7 @@ describe('Model', function() {
 
         it('watch() (gh-5964)', function() {
           return co(function*() {
-            const MyModel = db.model('gh5964', new Schema({ name: String }));
+            const MyModel = db.model('Test', new Schema({ name: String }));
 
             const doc = yield MyModel.create({ name: 'Ned Stark' });
 
@@ -5156,7 +4948,7 @@ describe('Model', function() {
           return co(function*() {
             const db = start();
 
-            const MyModel = db.model('gh5964', new Schema({ name: String }));
+            const MyModel = db.model('Test', new Schema({ name: String }));
 
             // Synchronous, before connection happens
             const changeStream = MyModel.watch();
@@ -5176,7 +4968,7 @@ describe('Model', function() {
         it('watch() close() prevents buffered watch op from running (gh-7022)', function() {
           return co(function*() {
             const db = start();
-            const MyModel = db.model('gh7022', new Schema({}));
+            const MyModel = db.model('Test', new Schema({}));
             const changeStream = MyModel.watch();
             const ready = new global.Promise(resolve => {
               changeStream.once('ready', () => {
@@ -5195,7 +4987,7 @@ describe('Model', function() {
         it('watch() close() closes the stream (gh-7022)', function() {
           return co(function*() {
             const db = yield start();
-            const MyModel = db.model('gh7022', new Schema({ name: String }));
+            const MyModel = db.model('Test', new Schema({ name: String }));
 
             yield MyModel.createCollection();
 
@@ -5217,9 +5009,10 @@ describe('Model', function() {
         let MyModel;
         const delay = ms => done => setTimeout(done, ms);
 
-        before(function(done) {
+        beforeEach(function(done) {
           const nestedSchema = new Schema({ foo: String });
-          MyModel = db.model('gh6362', new Schema({
+          db.deleteModel(/Test/);
+          MyModel = db.model('Test', new Schema({
             name: String,
             nested: nestedSchema,
             arr: [nestedSchema]
@@ -5253,7 +5046,7 @@ describe('Model', function() {
           return co(function*() {
             const db = start();
 
-            const MyModel = db.model('gh6362_2', new Schema({ name: String }));
+            const MyModel = db.model('Test', new Schema({ name: String }));
 
             // Don't wait for promise
             const sessionPromise = MyModel.startSession({ causalConsistency: true });
@@ -5416,7 +5209,7 @@ describe('Model', function() {
 
       let threw = false;
       try {
-        db.model('gh4475', testSchema);
+        db.model('Test', testSchema);
       } catch (error) {
         threw = true;
         assert.equal(error.message, 'You have a method and a property in ' +
@@ -5428,7 +5221,7 @@ describe('Model', function() {
 
     it('emits errors in create cb (gh-3222) (gh-3478)', function(done) {
       const schema = new Schema({ name: 'String' });
-      const Movie = db.model('gh3222', schema);
+      const Movie = db.model('Movie', schema);
 
       Movie.on('error', function(error) {
         assert.equal(error.message, 'fail!');
@@ -5445,7 +5238,7 @@ describe('Model', function() {
       const testSchema = new mongoose.Schema({
         name: String
       });
-      const Test = db.model('gh4449_0', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const t = new Test();
       Test.create(t, function(error, t2) {
@@ -5456,7 +5249,7 @@ describe('Model', function() {
     });
 
     it('emits errors correctly from exec (gh-4500)', function(done) {
-      const someModel = db.model('gh4500', new Schema({}));
+      const someModel = db.model('Test', new Schema({}));
 
       someModel.on('error', function(error) {
         assert.equal(error.message, 'This error will not disappear');
@@ -5483,7 +5276,7 @@ describe('Model', function() {
         }
       }, { id: false });
 
-      const Parent = db.model('gh5548', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const doc = new Parent({ child: { name: 'test' } });
       assert.ok(!doc.id);
@@ -5540,7 +5333,7 @@ describe('Model', function() {
           num: Number
         });
 
-        const M = db.model('gh3998', schema);
+        const M = db.model('Test', schema);
 
         const ops = [
           {
@@ -5574,7 +5367,7 @@ describe('Model', function() {
           num: Number
         });
 
-        const M = db.model('gh5708', schema);
+        const M = db.model('Test', schema);
 
         const ops = [
           {
@@ -5605,7 +5398,7 @@ describe('Model', function() {
           num: Number
         }, { timestamps: true });
 
-        const M = db.model('gh5708_ts', schema);
+        const M = db.model('Test', schema);
 
         const ops = [
           {
@@ -5652,7 +5445,7 @@ describe('Model', function() {
           timestamps: true
         });
 
-        const Parent = db.model('gh7032_Parent', parentSchema);
+        const Parent = db.model('Parent', parentSchema);
 
         return co(function*() {
           yield Parent.create({ children: [{ name: 'foo' }] });
@@ -5677,7 +5470,7 @@ describe('Model', function() {
       it('with timestamps and replaceOne (gh-5708)', function() {
         const schema = new Schema({ num: Number }, { timestamps: true });
 
-        const M = db.model('gh5708_ts2', schema);
+        const M = db.model('Test', schema);
 
         return co(function*() {
           yield M.create({ num: 42 });
@@ -5704,7 +5497,7 @@ describe('Model', function() {
         const nested = new Schema({ name: String }, { timestamps: true });
         const schema = new Schema({ nested: [nested] }, { timestamps: true });
 
-        const M = db.model('gh7032', schema);
+        const M = db.model('Test', schema);
 
         return co(function*() {
           yield M.create({ nested: [] });
@@ -5731,7 +5524,7 @@ describe('Model', function() {
         const nested = new Schema({ name: String });
         const schema = new Schema({ nested: nested });
 
-        const Model = db.model('gh7534', schema);
+        const Model = db.model('Test', schema);
 
         return Model.
           bulkWrite([{
@@ -5753,7 +5546,7 @@ describe('Model', function() {
 
       it('throws an error if no update object is provided (gh-8331)', function() {
         const userSchema = new Schema({ name: { type: String, required: true } });
-        const User = db.model('gh8331', userSchema);
+        const User = db.model('User', userSchema);
 
         return co(function*() {
           const createdUser = yield User.create({ name: 'Hafez' });
@@ -5799,7 +5592,7 @@ describe('Model', function() {
         const schema = new mongoose.Schema({
           amount : mongoose.Schema.Types.Decimal
         });
-        const Money = db.model('gh5190', schema);
+        const Money = db.model('Test', schema);
 
         Money.insertMany([{ amount : '123.45' }], function(error) {
           assert.ifError(error);
@@ -5813,7 +5606,7 @@ describe('Model', function() {
         name: String
       });
 
-      const Model = db.model('gh5323', schema);
+      const Model = db.model('Test', schema);
       const arr = [
         { name: 'test-1' },
         { name: 'test-2' }
@@ -5837,7 +5630,7 @@ describe('Model', function() {
     it('.create() with non-object (gh-2037)', function(done) {
       const schema = new mongoose.Schema({ name: String });
 
-      const Model = db.model('gh2037', schema);
+      const Model = db.model('Test', schema);
 
       Model.create(1, function(error) {
         assert.ok(error);
@@ -5849,7 +5642,7 @@ describe('Model', function() {
     it('save() with unacknowledged writes (gh-6012)', function() {
       const schema = new mongoose.Schema({ name: String }, { safe: false });
 
-      const Model = db.model('gh6012', schema);
+      const Model = db.model('Test', schema);
 
       return Model.create({});
     });
@@ -5857,47 +5650,12 @@ describe('Model', function() {
     it('save() with unacknowledged writes in options (gh-6012)', function() {
       const schema = new mongoose.Schema({ name: String });
 
-      const Model = db.model('gh6012_1', schema);
+      const Model = db.model('Test', schema);
       const doc = new Model();
 
       return doc.save({ safe: { w: 0 } });
     });
 
-    it('save() with acknowledged writes fail if topology is not replica set (gh-6862)', function(done) {
-      // If w > 1 and there is no replica sets, mongodb will throw BadValue error
-      // This test uses this to check if option `w` is correctly propagated to mongodb
-
-      // skip this test if the server is a replica set
-      if (db.client.topology.constructor.name === 'ReplSet') {
-        return this.skip();
-      }
-
-      const schemaA = new Schema({
-        name: String
-      }, { writeConcern: { w: 2 }});
-      const schemaB = new Schema({
-        name: String
-      });
-
-      const UserA = db.model('gh6862_1', schemaA);
-      const UserB = db.model('gh6862_2', schemaB);
-
-      const userA = new UserA();
-      const userB = new UserB();
-      userA.save(function(error) {
-        assert.ok(error);
-        assert.equal(error.name, 'MongoError');
-        assert.equal(error.codeName, 'BadValue');
-
-        userB.save({ w: 2 },function(error) {
-          assert.ok(error);
-          assert.equal(error.name, 'MongoError');
-          assert.equal(error.codeName, 'BadValue');
-          done();
-        });
-      });
-    });
-
     it.skip('save() with wtimeout defined in schema (gh-6862)', function(done) {
       // If you want to test this, setup replica set with 1 primary up and 1 secondary down
       this.timeout(process.env.TRAVIS ? 9000 : 5500);
@@ -5909,7 +5667,7 @@ describe('Model', function() {
           wtimeout: 1000
         }
       });
-      const User = db.model('gh6862_3', schema);
+      const User = db.model('User', schema);
       const user = new User();
       user.name = 'Jon Snow';
       user.save(function(error) {
@@ -5931,7 +5689,7 @@ describe('Model', function() {
       const schema = new Schema({
         name: String
       });
-      const User = db.model('gh6862_4', schema);
+      const User = db.model('User', schema);
       const user = new User();
       user.name = 'Jon Snow';
       user.save({ w: 2, wtimeout: 1000 }, function(error) {
@@ -5951,7 +5709,7 @@ describe('Model', function() {
         num: Number
       });
 
-      const M = db.model('gh3998_0', schema);
+      const M = db.model('Test', schema);
 
       const ops = [
         {
@@ -5994,7 +5752,7 @@ describe('Model', function() {
         num: Number
       });
 
-      const M = db.model('gh3998_1', schema);
+      const M = db.model('Test', schema);
 
       const ops = [
         {
@@ -6028,7 +5786,7 @@ describe('Model', function() {
         }
       });
 
-      const Model = db.model('gh6069', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         const doc = yield Model.create({ name: 'Val' });
@@ -6057,8 +5815,8 @@ describe('Model', function() {
         }
       });
 
-      const M1 = db.model('gh-2442-1', s1, 'gh-2442');
-      const M2 = db.model('gh-2442-2', s2, 'gh-2442');
+      const M1 = db.model('Test', s1);
+      const M2 = db.model('Test1', s2, 'tests');
 
       M1.create({array: {}}, function(err, doc) {
         assert.ifError(err);
@@ -6098,7 +5856,7 @@ describe('Model', function() {
         name: String
       });
 
-      const Test = db.model('gh6456', schema);
+      const Test = db.model('Test', schema);
 
       const test = new Test({
         name: 'Billy'
@@ -6118,27 +5876,14 @@ describe('Model', function() {
       });
     });
 
-    it('listIndexes() (gh-6281)', function() {
-      return co(function*() {
-        const M = db.model('gh6281', new Schema({
-          name: { type: String, index: true }
-        }), 'gh6281_0');
-
-        yield M.init();
-
-        const indexes = yield M.listIndexes();
-        assert.deepEqual(indexes.map(i => i.key), [
-          { _id: 1 },
-          { name: 1 }
-        ]);
-      });
-    });
-
     it('syncIndexes() (gh-6281)', function() {
+      this.timeout(10000);
+
       return co(function*() {
-        let M = db.model('gh6281', new Schema({
+        const coll = 'tests' + random();
+        let M = db.model('Test', new Schema({
           name: { type: String, index: true }
-        }, { autoIndex: false }), 'gh6281');
+        }, { autoIndex: false }), coll);
 
         let dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, []);
@@ -6150,9 +5895,10 @@ describe('Model', function() {
         ]);
 
         // New model, same collection, index on different property
-        M = db.model('gh6281_0', new Schema({
+        db.deleteModel(/Test/);
+        M = db.model('Test', new Schema({
           otherName: { type: String, index: true }
-        }, { autoIndex: false }), 'gh6281');
+        }, { autoIndex: false }), coll);
 
         dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, ['name_1']);
@@ -6164,9 +5910,10 @@ describe('Model', function() {
         ]);
 
         // New model, same collection, different options
-        M = db.model('gh6281_1', new Schema({
+        db.deleteModel(/Test/);
+        M = db.model('Test', new Schema({
           otherName: { type: String, unique: true }
-        }, { autoIndex: false }), 'gh6281');
+        }, { autoIndex: false }), coll);
 
         dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, ['otherName_1']);
@@ -6180,15 +5927,21 @@ describe('Model', function() {
         // Re-run syncIndexes(), shouldn't change anything
         dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, []);
+
+        yield M.collection.drop();
       });
     });
 
     it('syncIndexes() with different key order (gh-8135)', function() {
+      this.timeout(10000);
+
       return co(function*() {
         const opts = { autoIndex: false };
         let schema = new Schema({ name: String, age: Number }, opts);
         schema.index({ name: 1, age: -1 });
-        let M = db.model('gh8135', schema, 'gh8135');
+
+        const coll = 'tests' + random();
+        let M = db.model('Test', schema, coll);
 
         let dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, []);
@@ -6202,7 +5955,8 @@ describe('Model', function() {
         // New model, same collection, different key order
         schema = new Schema({ name: String, age: Number }, opts);
         schema.index({ age: -1, name: 1 });
-        M = db.model('gh8135_0', schema, 'gh8135');
+        db.deleteModel(/Test/);
+        M = db.model('Test', schema, coll);
 
         dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, ['name_1_age_-1']);
@@ -6210,19 +5964,19 @@ describe('Model', function() {
     });
 
     it('using `new db.model()()` (gh-6698)', function(done) {
-      db.model('gh6698', new Schema({
+      db.model('Test', new Schema({
         name: String
       }));
 
       assert.throws(function() {
-        new db.model('gh6698')({ name: 'test' });
+        new db.model('Test')({ name: 'test' });
       }, /should not be run with `new`/);
 
       done();
     });
 
     it('throws if non-function passed as callback (gh-6640)', function(done) {
-      const Model = db.model('gh6640', new Schema({
+      const Model = db.model('Test', new Schema({
         name: String
       }));
 
@@ -6252,7 +6006,7 @@ describe('Model', function() {
         name: String
       });
 
-      const Test = db.model('gh6456_2', schema);
+      const Test = db.model('Test', schema);
 
       const test = new Test({
         name: 'Sarah'
@@ -6289,46 +6043,33 @@ describe('Model', function() {
       });
 
 
-      const Note = db.model('gh6611', noteSchema);
+      const Note = db.model('Test', noteSchema);
       return co(function*() {
         yield Note.create({ body: 'a note.' });
         const doc = yield Note.findOne({});
         assert.strictEqual(doc.body, 'a note, part deux.');
       });
     });
-    it('createCollection() (gh-6711)', function() {
-      const userSchema = new Schema({
-        name: String
-      });
-      const rand = random();
-      const model = db.model('gh6711_' + rand + '_User', userSchema);
-
-      return co(function*() {
-        yield model.createCollection();
-        // If the collection is not created, the following will throw
-        // MongoError: Collection [mongoose_test.create_xxx_users] not found.
-        yield db.collection('gh6711_' + rand + '_users').stats();
-      });
-    });
 
     it('createCollection() respects schema collation (gh-6489)', function() {
       const userSchema = new Schema({
         name: String
       }, { collation: { locale: 'en_US', strength: 1 } });
-      const Model = db.model('gh6489_User', userSchema, 'gh6489_User');
+      const Model = db.model('User', userSchema);
 
       return co(function*() {
+        yield Model.collection.drop();
         yield Model.createCollection();
 
         // If the collection is not created, the following will throw
         // MongoError: Collection [mongoose_test.create_xxx_users] not found.
-        yield db.collection('gh6489_User').stats();
+        yield db.collection('users').stats();
 
         yield Model.create([{ name: 'alpha' }, { name: 'Zeta' }]);
 
         // Ensure that the default collation is set. Mongoose will set the
         // collation on the query itself (see gh-4839).
-        const res = yield db.collection('gh6489_User').
+        const res = yield db.collection('users').
           find({}).sort({ name: 1 }).toArray();
         assert.deepEqual(res.map(v => v.name), ['alpha', 'Zeta']);
       });
@@ -6336,9 +6077,9 @@ describe('Model', function() {
   });
 
   it('dropDatabase() after init allows re-init (gh-6967)', function() {
-    const db = mongoose.createConnection(start.uri + '_6967');
+    this.timeout(10000);
 
-    const Model = db.model('gh6640', new Schema({
+    const Model = db.model('Test', new Schema({
       name: { type: String, index: true }
     }));
 
@@ -6354,7 +6095,7 @@ describe('Model', function() {
       try {
         yield Model.listIndexes();
       } catch (err) {
-        assert.ok(err.message.indexOf('_6967') !== -1,
+        assert.ok(err.message.indexOf('tests') !== -1,
           err.message);
         threw = true;
       }
@@ -6377,7 +6118,7 @@ describe('Model', function() {
       items: { type: [String], default: [] }
     });
 
-    const Record = db.model('gh7138', schema);
+    const Record = db.model('Test', schema);
 
     const record = { key: key, items: ['A', 'B', 'C'] };
 
@@ -6392,14 +6133,14 @@ describe('Model', function() {
 
   it('can JSON.stringify(Model.schema) with nested (gh-7220)', function() {
     const nested = Schema({ name: String });
-    const Model = mongoose.model('gh7220', Schema({ nested }));
+    const Model = db.model('Test', Schema({ nested }));
 
     const _schema = JSON.parse(JSON.stringify(Model.schema));
     assert.ok(_schema.obj.nested);
   });
 
   it('Model.events() (gh-7125)', function() {
-    const Model = db.model('gh7125', Schema({
+    const Model = db.model('Test', Schema({
       name: { type: String, validate: () => false }
     }));
 
@@ -6433,7 +6174,7 @@ describe('Model', function() {
       sessions.push(this.$session());
     });
 
-    const SampleModel = db.model('gh7742', schema);
+    const SampleModel = db.model('Test', schema);
 
     return co(function*() {
       yield SampleModel.create({ name: 'foo' });
@@ -6463,7 +6204,7 @@ describe('Model', function() {
       sessions.push(this.$session());
     });
 
-    const SampleModel = db.model('gh7742_remove', schema);
+    const SampleModel = db.model('Test', schema);
 
     return co(function*() {
       yield SampleModel.create({ name: 'foo' });
@@ -6488,7 +6229,7 @@ describe('Model', function() {
       sessions.push(this.$session());
     });
 
-    const SampleModel = db.model('gh7769_validate', schema);
+    const SampleModel = db.model('Test', schema);
 
     return co(function*() {
       // start session
@@ -6526,7 +6267,7 @@ describe('Model', function() {
       schema.pre('findOne', function() {
         ++called;
       });
-      const Model = db.model('gh7790', schema);
+      const Model = db.model('Test', schema);
 
       yield Model.create({ name: 'foo' });
 
@@ -6546,7 +6287,7 @@ describe('Model', function() {
       docs.push(doc);
       next();
     });
-    const Model = db.model('gh7832', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.create({ _id: 1 });
@@ -6565,7 +6306,7 @@ describe('Model', function() {
   });
 
   it('throws readable error if calling Model function with bad context (gh-7957)', function() {
-    const Model = db.model('gh7957_new', Schema({ name: String }));
+    const Model = db.model('Test', Schema({ name: String }));
 
     assert.throws(() => {
       new Model.discriminator('gh5957_fail', Schema({ doesntMatter: String }));
@@ -6580,7 +6321,7 @@ describe('Model', function() {
 
   describe('exists() (gh-6872)', function() {
     it('returns true if document exists', function() {
-      const Model = db.model('gh6872_exists', new Schema({ name: String }));
+      const Model = db.model('Test', new Schema({ name: String }));
 
       return Model.create({ name: 'foo' }).
         then(() => Model.exists({ name: 'foo' })).
@@ -6592,7 +6333,7 @@ describe('Model', function() {
     });
 
     it('returns false if no doc exists', function() {
-      const Model = db.model('gh6872_false', new Schema({ name: String }));
+      const Model = db.model('Test', new Schema({ name: String }));
 
       return Model.create({ name: 'foo' }).
         then(() => Model.exists({ name: 'bar' })).
@@ -6602,7 +6343,7 @@ describe('Model', function() {
     });
 
     it('options (gh-8075)', function() {
-      const Model = db.model('gh8075', new Schema({ name: String }));
+      const Model = db.model('Test', new Schema({ name: String }));
 
       return Model.exists({}).
         then(res => assert.ok(!res)).
@@ -6612,7 +6353,7 @@ describe('Model', function() {
   });
 
   it('Model.validate() (gh-7587)', function() {
-    const Model = db.model('gh7587', new Schema({
+    const Model = db.model('Test', new Schema({
       name: {
         first: {
           type: String,

From 6303d55ec97673b43802de65aa53e06e8f300d5b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jan 2020 22:35:54 -0500
Subject: [PATCH 0430/2348] test: fix test #8481

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index df34878f671..05dcb3a7b2a 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6095,7 +6095,7 @@ describe('Model', function() {
       try {
         yield Model.listIndexes();
       } catch (err) {
-        assert.ok(err.message.indexOf('tests') !== -1,
+        assert.ok(err.message.indexOf('test') !== -1,
           err.message);
         threw = true;
       }

From bfbc92110cc16cee926b5575508bab0efb297a97 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jan 2020 12:57:15 -0500
Subject: [PATCH 0431/2348] test: fix tests re: #8536

---
 test/model.discriminator.test.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 388aa1a6e32..7c0ba1b9eab 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1314,13 +1314,15 @@ describe('model', function() {
       const plugin = (schema) => { };
 
       const schema = new Schema({ value: String });
-      schema.plugin(plugin)
+      schema.plugin(plugin);
       const model = mongoose.model('Model', schema);
 
       const discriminator = model.discriminator('Desc', new Schema({ anotherValue: String }));
 
       const copiedPlugin = discriminator.schema.plugins.find(p => p.fn === plugin);
       assert.ok(!!copiedPlugin);
+
+      mongoose.deleteModel(/Model/);
     });
   });
 

From 41b3ff5dc9abf743b337a1260c344d4cd438ac77 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jan 2020 12:59:58 -0500
Subject: [PATCH 0432/2348] chore: release 5.8.10

---
 History.md   | 15 +++++++++++++++
 package.json |  2 +-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 64019fdca27..1f6b666ac2d 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,18 @@
+5.8.10 / 2020-01-27
+===================
+ * perf(document): improve performance of document creation by skipping unnecessary split() calls #8533 [igrunert-atlassian](https://github.com/igrunert-atlassian)
+ * fix(document): only call validate once for deeply nested subdocuments #8532 #8531 [taxilian](https://github.com/taxilian)
+ * fix(document): create document array defaults in forward order, not reverse #8514
+ * fix(document): allow function as message for date min/max validator #8512
+ * fix(populate): don't try to populate embedded discriminator that has populated path but no `refPath` #8527
+ * fix(document): plugins from base schema when creating a discriminator #8536 [samgladstone](https://github.com/samgladstone)
+ * fix(document): ensure parent and ownerDocument are set for subdocs in document array defaults #8509
+ * fix(document): dont set undefined keys to null if minimize is false #8504
+ * fix(update): bump timestamps when using update aggregation pipelines #8524
+ * fix(model): ensure `cleanIndexes()` drops indexes with different collations #8521
+ * docs(model): document `insertMany` `lean` option #8522
+ * docs(connections): document `authSource` option #8517
+
 5.8.9 / 2020-01-17
 ==================
  * fix(populate): skip populating embedded discriminator array values that don't have a `refPath` #8499
diff --git a/package.json b/package.json
index 1fbf774bdc2..535270c38a3 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.10-pre",
+  "version": "5.8.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 02a6ff581242999a2d3e1f89d3a3bc3500ae2792 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Mon, 27 Jan 2020 13:47:48 -0600
Subject: [PATCH 0433/2348] Fix SchemaType.clone()

---
 lib/schematype.js                             | 12 ++-
 ...schema.type.test.js => schematype.test.js} | 92 +++++++++++++++++++
 2 files changed, 103 insertions(+), 1 deletion(-)
 rename test/{schema.type.test.js => schematype.test.js} (61%)

diff --git a/lib/schematype.js b/lib/schematype.js
index f5bda24f89e..35c028fe9fc 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1433,7 +1433,17 @@ SchemaType.prototype.clone = function() {
   const options = Object.assign({}, this.options);
   const schematype = new this.constructor(this.path, options, this.instance);
   schematype.validators = this.validators.slice();
-  schematype.requiredValidator = this.requiredValidator;
+  if (this.requiredValidator !== undefined) schematype.requiredValidator = this.requiredValidator;
+  if (this.defaultValue !== undefined) schematype.defaultValue = this.defaultValue;
+  if (this.$immutable !== undefined && this.options.immutable === undefined) {
+    schematype.$immutable = this.$immutable;
+
+    handleImmutable(schematype);
+  }
+  if (this._index !== undefined) schematype._index = this._index;
+  if (this.selected !== undefined) schematype.selected = this.selected;
+  if (this.isRequired !== undefined) schematype.isRequired = this.isRequired;
+  if (this.originalRequiredValue !== undefined) schematype.originalRequiredValue = this.originalRequiredValue;
   schematype.getters = this.getters.slice();
   schematype.setters = this.setters.slice();
   return schematype;
diff --git a/test/schema.type.test.js b/test/schematype.test.js
similarity index 61%
rename from test/schema.type.test.js
rename to test/schematype.test.js
index d217615f3ce..a657abc9e8f 100644
--- a/test/schema.type.test.js
+++ b/test/schematype.test.js
@@ -100,4 +100,96 @@ describe('schematype', function() {
     assert.equal(err.name, 'ValidatorError');
     assert.equal(err.message, 'name is invalid!');
   });
+
+  describe.only('clone()', function () {
+    let schemaType;
+    beforeEach(function () {
+      schemaType = Schema({ value: String }).path('value');
+    });
+
+    function cloneAndTestDeepEquals() {
+      const clone = schemaType.clone();
+      assert.deepStrictEqual(clone, schemaType);
+    }
+    
+    it('clones added default', function () {
+      schemaType.default(() => 'abc');
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added getters', function () {
+      schemaType.get(v => v.trim());
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added immutable', function () {
+      // Note: cannot compare with deep equals due to the immutable function
+      schemaType.immutable(true);
+      let clonePath = schemaType.clone();
+
+      try {
+        assert.deepStrictEqual(clonePath, schemaType)
+      }
+      catch (err) {
+        if (!err.message.startsWith('Values have same structure but are not reference-equal:'))
+          throw err;
+      }
+    });
+
+    it('clones added index', function () {
+      schemaType.index(true);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added ref', function () {
+      schemaType.ref('User');
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added required', function () {
+      schemaType.required(true);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added select: false', function () {
+      schemaType.select(false);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added setter', function () {
+      schemaType.set(v => v.trim());
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added sparse', function () {
+      schemaType.sparse(true);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added sparse (index option)', function () {
+      schemaType.sparse(true);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added text (index option)', function () {
+      schemaType.text(true);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added unique (index option)', function () {
+      schemaType.unique(true);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones added validator', function () {
+      schemaType.validate(v => v.length > 3);
+      cloneAndTestDeepEquals();
+    });
+
+    it('clones updated caster', function () {
+      schemaType.cast(v => v.length > 3 ? v : v.trim());
+      cloneAndTestDeepEquals();
+    });
+
+  })
 });

From 3a161756d739fb4a1dba1110da59895f88a1ce71 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Mon, 27 Jan 2020 13:53:40 -0600
Subject: [PATCH 0434/2348] Oops, missed the only again..

---
 test/schematype.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/schematype.test.js b/test/schematype.test.js
index a657abc9e8f..c8d7a047aa3 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -101,7 +101,7 @@ describe('schematype', function() {
     assert.equal(err.message, 'name is invalid!');
   });
 
-  describe.only('clone()', function () {
+  describe('clone()', function () {
     let schemaType;
     beforeEach(function () {
       schemaType = Schema({ value: String }).path('value');

From e52b6ff59b9310bc227b0af79439f92c05efa74f Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Mon, 27 Jan 2020 14:06:33 -0600
Subject: [PATCH 0435/2348] lint

---
 test/schematype.test.js | 41 ++++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/test/schematype.test.js b/test/schematype.test.js
index c8d7a047aa3..b0a1bd0b6c2 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -101,9 +101,9 @@ describe('schematype', function() {
     assert.equal(err.message, 'name is invalid!');
   });
 
-  describe('clone()', function () {
+  describe.only('clone()', function() {
     let schemaType;
-    beforeEach(function () {
+    beforeEach(function() {
       schemaType = Schema({ value: String }).path('value');
     });
 
@@ -111,24 +111,24 @@ describe('schematype', function() {
       const clone = schemaType.clone();
       assert.deepStrictEqual(clone, schemaType);
     }
-    
-    it('clones added default', function () {
+
+    it('clones added default', function() {
       schemaType.default(() => 'abc');
       cloneAndTestDeepEquals();
     });
 
-    it('clones added getters', function () {
+    it('clones added getters', function() {
       schemaType.get(v => v.trim());
       cloneAndTestDeepEquals();
     });
 
-    it('clones added immutable', function () {
+    it('clones added immutable', function() {
       // Note: cannot compare with deep equals due to the immutable function
       schemaType.immutable(true);
-      let clonePath = schemaType.clone();
+      const clonePath = schemaType.clone();
 
       try {
-        assert.deepStrictEqual(clonePath, schemaType)
+        assert.deepStrictEqual(clonePath, schemaType);
       }
       catch (err) {
         if (!err.message.startsWith('Values have same structure but are not reference-equal:'))
@@ -136,60 +136,59 @@ describe('schematype', function() {
       }
     });
 
-    it('clones added index', function () {
+    it('clones added index', function() {
       schemaType.index(true);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added ref', function () {
+    it('clones added ref', function() {
       schemaType.ref('User');
       cloneAndTestDeepEquals();
     });
 
-    it('clones added required', function () {
+    it('clones added required', function() {
       schemaType.required(true);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added select: false', function () {
+    it('clones added select: false', function() {
       schemaType.select(false);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added setter', function () {
+    it('clones added setter', function() {
       schemaType.set(v => v.trim());
       cloneAndTestDeepEquals();
     });
 
-    it('clones added sparse', function () {
+    it('clones added sparse', function() {
       schemaType.sparse(true);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added sparse (index option)', function () {
+    it('clones added sparse (index option)', function() {
       schemaType.sparse(true);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added text (index option)', function () {
+    it('clones added text (index option)', function() {
       schemaType.text(true);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added unique (index option)', function () {
+    it('clones added unique (index option)', function() {
       schemaType.unique(true);
       cloneAndTestDeepEquals();
     });
 
-    it('clones added validator', function () {
+    it('clones added validator', function() {
       schemaType.validate(v => v.length > 3);
       cloneAndTestDeepEquals();
     });
 
-    it('clones updated caster', function () {
+    it('clones updated caster', function() {
       schemaType.cast(v => v.length > 3 ? v : v.trim());
       cloneAndTestDeepEquals();
     });
-
-  })
+  });
 });

From 48dd5fa93c35bc1412add97502eef7997b13f48e Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Mon, 27 Jan 2020 14:11:45 -0600
Subject: [PATCH 0436/2348] Don't validate against error message (fix node
 version tests)

---
 test/schematype.test.js | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/test/schematype.test.js b/test/schematype.test.js
index b0a1bd0b6c2..f5b6b7c7bac 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -101,7 +101,7 @@ describe('schematype', function() {
     assert.equal(err.message, 'name is invalid!');
   });
 
-  describe.only('clone()', function() {
+  describe('clone()', function() {
     let schemaType;
     beforeEach(function() {
       schemaType = Schema({ value: String }).path('value');
@@ -125,15 +125,14 @@ describe('schematype', function() {
     it('clones added immutable', function() {
       // Note: cannot compare with deep equals due to the immutable function
       schemaType.immutable(true);
-      const clonePath = schemaType.clone();
-
-      try {
-        assert.deepStrictEqual(clonePath, schemaType);
-      }
-      catch (err) {
-        if (!err.message.startsWith('Values have same structure but are not reference-equal:'))
-          throw err;
-      }
+      let clonePath = schemaType.clone();
+      assert.equal(schemaType.$immutable, clonePath.$immutable);
+      assert.equal(schemaType.setters.length, clonePath.setters.length);
+
+      schemaType.immutable(false);
+      clonePath = schemaType.clone();
+      assert.equal(schemaType.$immutable, clonePath.$immutable);
+      assert.equal(schemaType.setters.length, clonePath.setters.length);
     });
 
     it('clones added index', function() {

From 103beb06a65d5c51fd7cfd11952fe667d8b82362 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Mon, 27 Jan 2020 17:52:00 -0600
Subject: [PATCH 0437/2348] Remove unnecessary merge of schema with itself

---
 lib/helpers/model/discriminator.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index ef0a880f1b1..64765f51dbf 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -72,8 +72,6 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     if (baseSchema.paths._id &&
         baseSchema.paths._id.options &&
         !baseSchema.paths._id.options.auto) {
-      const originalSchema = schema;
-      utils.merge(schema, originalSchema);
       delete schema.paths._id;
       delete schema.tree._id;
     }

From 1645e2ed7f85e604f408bfe783ef6793daca8b88 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Tue, 28 Jan 2020 11:40:29 -0600
Subject: [PATCH 0438/2348] Push test for #8543 as discussed in #8546

---
 test/model.discriminator.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 7c0ba1b9eab..9a89de40c2d 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1324,6 +1324,22 @@ describe('model', function() {
 
       mongoose.deleteModel(/Model/);
     });
+
+    describe('does not have unintended side effects', function() {
+      // Delete every model
+      afterEach(function() { mongoose.deleteModel(/.+/); });
+
+      function throwErrorOnClone() { throw new Error('clone() was called on the unrelated schema'); };
+
+      it('when the base schema has an _id that is not auto generated', function() {
+        const unrelatedSchema = new mongoose.Schema({});
+        unrelatedSchema.clone = throwErrorOnClone;
+        mongoose.model('UnrelatedModel', unrelatedSchema);
+
+        const model = mongoose.model('Model', new mongoose.Schema({ _id: mongoose.Types.ObjectId }, { _id: false }));
+        model.discriminator('Discrimintaor', new mongoose.Schema({}).clone());
+      });
+    });
   });
 
   describe('bug fixes', function() {

From 7b6d5e51b3f5ba53def519664a4a4103e69ff7fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 28 Jan 2020 17:34:49 -0500
Subject: [PATCH 0439/2348] fix(drivers): avoid unnecessary caught error when
 importing

Fix #8528
---
 lib/drivers/node-mongodb-native/collection.js | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index bfe817a6692..71046663d35 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -177,18 +177,19 @@ function iter(i) {
   };
 }
 
-for (const i in Collection.prototype) {
+for (const key of Object.keys(Collection.prototype)) {
   // Janky hack to work around gh-3005 until we can get rid of the mongoose
   // collection abstraction
-  try {
-    if (typeof Collection.prototype[i] !== 'function') {
-      continue;
-    }
-  } catch (e) {
+  const descriptor = Object.getOwnPropertyDescriptor(Collection.prototype, key);
+  // Skip properties with getters because they may throw errors (gh-8528)
+  if (descriptor.get !== undefined) {
+    continue;
+  }
+  if (typeof Collection.prototype[key] !== 'function') {
     continue;
   }
 
-  iter(i);
+  iter(key);
 }
 
 /**

From d1c5bba2f85203f96a76a16357afb21ee1533337 Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Mon, 27 Jan 2020 16:37:36 -0700
Subject: [PATCH 0440/2348] Add support for deepStackTrace schema option to aid
 debugging

---
 lib/document.js                | 26 +++++++++++++++++++++++---
 lib/error/parallelValidate.js  | 10 +++++++++-
 lib/schema.js                  |  3 +++
 lib/schema/SingleNestedPath.js | 19 +++++++++++++++----
 lib/schema/documentarray.js    |  7 +++++--
 lib/schematype.js              |  6 ++++++
 test/document.test.js          |  2 +-
 7 files changed, 62 insertions(+), 11 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index a153309a07d..67a79d3237c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2030,9 +2030,12 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
   let parallelValidate;
 
   if (this.$__.validating) {
-    parallelValidate = new ParallelValidateError(this);
+    parallelValidate = new ParallelValidateError(this, {
+      parentStack: options && options.parentStack,
+      conflictStack: this.$__.validating.stack
+    });
   } else {
-    this.$__.validating = new ParallelValidateError(this);
+    this.$__.validating = new ParallelValidateError(this, {parentStack: options && options.parentStack});
   }
 
   if (typeof pathsToValidate === 'function') {
@@ -2208,6 +2211,15 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       (typeof options === 'object') &&
       ('validateModifiedOnly' in options);
 
+  const saveDeepStacktrace = (
+        options && 
+        (typeof options === 'object') &&
+        !!options['deepStackTrace'])
+     || !!this.schema.options.deepStackTrace;
+  const parentStack = saveDeepStacktrace && options &&
+      (typeof options === 'object') &&
+      options.parentStack || [];
+
   let shouldValidateModifiedOnly;
   if (hasValidateModifiedOnlyOption) {
     shouldValidateModifiedOnly = !!options.validateModifiedOnly;
@@ -2294,6 +2306,9 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     validated[path] = true;
     total++;
 
+    let stackToHere = saveDeepStacktrace ?
+        [(new Error().stack)].concat(parentStack) : void 0;
+
     process.nextTick(function() {
       const p = _this.schema.path(path);
 
@@ -2320,6 +2335,11 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
         _this.$__.pathsToScopes[path] :
         _this;
 
+      const doValidateOptions = {
+        skipSchemaValidators: skipSchemaValidators[path],
+        path: path,
+        parentStack: stackToHere
+      };
       p.doValidate(val, function(err) {
         if (err && (!p.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
           if (p.$isSingleNested &&
@@ -2330,7 +2350,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
           _this.invalidate(path, err, undefined, true);
         }
         --total || complete();
-      }, scope, { skipSchemaValidators: skipSchemaValidators[path], path: path });
+      }, scope, doValidateOptions);
     });
   };
 
diff --git a/lib/error/parallelValidate.js b/lib/error/parallelValidate.js
index c5cc83b89fa..c0fedc88224 100644
--- a/lib/error/parallelValidate.js
+++ b/lib/error/parallelValidate.js
@@ -13,10 +13,18 @@ const MongooseError = require('./mongooseError');
  * @api private
  */
 
-function ParallelValidateError(doc) {
+function ParallelValidateError(doc, opts) {
   const msg = 'Can\'t validate() the same doc multiple times in parallel. Document: ';
   MongooseError.call(this, msg + doc._id);
   this.name = 'ParallelValidateError';
+  if (opts && opts.parentStack) {
+      // Provide a full async stack, most recent first
+      this.stack = this.stack + "\n\n" + opts.parentStack.join('\n\n');
+  }
+  // You need to know to look for this, but having it can be very helpful
+  // for tracking down issues when combined with the deepStackTrace schema
+  // option
+  this.conflictStack = opts && opts.conflictStack;
 }
 
 /*!
diff --git a/lib/schema.js b/lib/schema.js
index 06cd1d4341b..e6b0c934c21 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -402,6 +402,9 @@ Schema.prototype.defaultOptions = function(options) {
     strict: 'strict' in baseOptions ? baseOptions.strict : true,
     bufferCommands: true,
     capped: false, // { size, max, autoIndexId }
+    // Setting to true may help with debugging but will have performance
+    // consequences
+    deepStackTrace: false, 
     versionKey: '__v',
     discriminatorKey: '__t',
     minimize: true,
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index a33d65bf74c..887f0f496ad 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -237,9 +237,17 @@ SingleNestedPath.prototype.doValidate = function(value, fn, scope, options) {
     if (!(value instanceof Constructor)) {
       value = new Constructor(value, null, scope);
     }
-
-    return value.validate(fn);
+    try {
+        return value.validate(fn);
+    } catch (err) {
+        // Save the parent stack on the error
+        if (options.parentStack) {
+            err.parentStack = options.parentStack;
+        }
+        throw err;
+    }
   }
+  const parentStack = options && options.parentStack;
 
   SchemaType.prototype.doValidate.call(this, value, function(error) {
     if (error) {
@@ -249,8 +257,11 @@ SingleNestedPath.prototype.doValidate = function(value, fn, scope, options) {
       return fn(null);
     }
 
-    value.validate(fn);
-  }, scope);
+    value.validate(fn, {
+        deepStackTrace: !!parentStack,
+        parentStack: parentStack,
+    });
+  }, scope, options);
 };
 
 /**
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 3ec0e3cc27d..b23d10ee307 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -197,7 +197,7 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
 
   const _this = this;
   try {
-    SchemaType.prototype.doValidate.call(this, array, cb, scope);
+    SchemaType.prototype.doValidate.call(this, array, cb, scope, options);
   } catch (err) {
     err.$isArrayValidatorError = true;
     return fn(err);
@@ -251,7 +251,10 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
         doc = array[i] = new Constructor(doc, array, undefined, undefined, i);
       }
 
-      doc.$__validate(callback);
+      doc.$__validate(null, {
+          parentStack: options && options.parentStack,
+          deepStackTrace: !!(options && options.parentStack)
+        }, callback);
     }
   }
 };
diff --git a/lib/schematype.js b/lib/schematype.js
index 35c028fe9fc..c8f8f8c65f5 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1060,6 +1060,9 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
       const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
       err = new ErrorConstructor(validatorProperties);
       err[validatorErrorSymbol] = true;
+      if (options.parentStack) {
+          error.parentStack = options.parentStack;
+      }
       immediate(function() {
         fn(err);
       });
@@ -1101,6 +1104,9 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
           if (error.message) {
             validatorProperties.message = error.message;
           }
+          if (options && options.parentStack) {
+            validatorProperties.deepStack = options.parentStack;
+          }
         }
         if (ok != null && typeof ok.then === 'function') {
           ok.then(
diff --git a/test/document.test.js b/test/document.test.js
index aa90f45a210..72c01900d9a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -586,7 +586,7 @@ describe('document', function() {
     const Model = db.model('gh8468-2', Schema({
       name: String,
       keys: [keySchema],
-    }));
+    }, {deepStackTrace: true}));
     const doc = new Model({
       name: 'test',
       keys: [

From acf13520db3cd75725130952faa57a669433b9e5 Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Tue, 28 Jan 2020 15:47:13 -0700
Subject: [PATCH 0441/2348] Add the path to the parentStack to make it easier
 to see where it came from

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 67a79d3237c..935d31bd814 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2307,7 +2307,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     total++;
 
     let stackToHere = saveDeepStacktrace ?
-        [(new Error().stack)].concat(parentStack) : void 0;
+        [(new Error().stack), path].concat(parentStack) : void 0;
 
     process.nextTick(function() {
       const p = _this.schema.path(path);

From 7812ba8c3734c80cc8ad2dd9688f1dc5e2726020 Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Tue, 28 Jan 2020 16:03:22 -0700
Subject: [PATCH 0442/2348] Add a check that options exists to fix unit tests

---
 lib/schematype.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index c8f8f8c65f5..fab04d90d42 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1060,7 +1060,7 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
       const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
       err = new ErrorConstructor(validatorProperties);
       err[validatorErrorSymbol] = true;
-      if (options.parentStack) {
+      if (options && options.parentStack) {
           error.parentStack = options.parentStack;
       }
       immediate(function() {

From c42cc996a3e4be2adf580c27b21094317306f1b1 Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Tue, 28 Jan 2020 16:10:02 -0700
Subject: [PATCH 0443/2348] Fix issue where some paths were still having
 validate() called more than once

---
 lib/document.js | 74 +++++++++++++++++++++++++------------------------
 1 file changed, 38 insertions(+), 36 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 935d31bd814..fbee7b187b4 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2086,7 +2086,7 @@ function _getPathsToValidate(doc) {
   _evaluateRequiredFunctions(doc);
 
   // only validate required fields when necessary
-  let paths = Object.keys(doc.$__.activePaths.states.require).filter(function(path) {
+  let paths = new Set(Object.keys(doc.$__.activePaths.states.require).filter(function(path) {
     if (!doc.isSelected(path) && !doc.isModified(path)) {
       return false;
     }
@@ -2094,38 +2094,41 @@ function _getPathsToValidate(doc) {
       return doc.$__.cachedRequired[path];
     }
     return true;
-  });
+  }));
 
-  paths = paths.concat(Object.keys(doc.$__.activePaths.states.init));
-  paths = paths.concat(Object.keys(doc.$__.activePaths.states.modify));
-  paths = paths.concat(Object.keys(doc.$__.activePaths.states.default));
+
+  function addToPaths(p) { paths.add(p); }
+  Object.keys(doc.$__.activePaths.states.init).forEach(addToPaths);
+  Object.keys(doc.$__.activePaths.states.modify).forEach(addToPaths);
+  Object.keys(doc.$__.activePaths.states.default).forEach(addToPaths);
 
   const subdocs = doc.$__getAllSubdocs();
-  let subdoc;
-  len = subdocs.length;
   const modifiedPaths = doc.modifiedPaths();
-  for (i = 0; i < len; ++i) {
-    subdoc = subdocs[i];
-    if (subdoc.$basePath &&
-        doc.isModified(subdoc.$basePath, modifiedPaths) &&
-        !doc.isDirectModified(subdoc.$basePath) &&
-        !doc.$isDefault(subdoc.$basePath)) {
+  for (const subdoc of subdocs) {
+    if (subdoc.$basePath) {
       // Remove child paths for now, because we'll be validating the whole
       // subdoc
-      paths = paths.filter(function(p) {
-        return p != null && p.indexOf(subdoc.$basePath + '.') !== 0;
-      });
-      paths.push(subdoc.$basePath); // This can cause duplicates, make unique below
-      skipSchemaValidators[subdoc.$basePath] = true;
+      for (const p of paths) {
+        if (p === null || p.startsWith(subdoc.$basePath + '.')) {
+            paths.delete(p);
+        }
+      }
+
+      if (doc.isModified(subdoc.$basePath, modifiedPaths) &&
+              !doc.isDirectModified(subdoc.$basePath) &&
+              !doc.$isDefault(subdoc.$basePath)) {
+        paths.add(subdoc.$basePath);
+
+        skipSchemaValidators[subdoc.$basePath] = true;
+      }
     }
   }
 
+  // from here on we're not removing items from paths
+
   // gh-661: if a whole array is modified, make sure to run validation on all
   // the children as well
-  len = paths.length;
-  for (i = 0; i < len; ++i) {
-    const path = paths[i];
-
+  for (const path of paths) {
     const _pathType = doc.schema.path(path);
     if (!_pathType ||
         !_pathType.$isMongooseArray ||
@@ -2147,34 +2150,33 @@ function _getPathsToValidate(doc) {
         if (Array.isArray(val[j])) {
           _pushNestedArrayPaths(val[j], paths, path + '.' + j);
         } else {
-          paths.push(path + '.' + j);
+          paths.add(path + '.' + j);
         }
       }
     }
   }
 
   const flattenOptions = { skipArrays: true };
-  len = paths.length;
-  for (i = 0; i < len; ++i) {
-    const pathToCheck = paths[i];
+  for (const pathToCheck of paths) {
     if (doc.schema.nested[pathToCheck]) {
       let _v = doc.$__getValue(pathToCheck);
       if (isMongooseObject(_v)) {
         _v = _v.toObject({ transform: false });
       }
       const flat = flatten(_v, pathToCheck, flattenOptions, doc.schema);
-      paths = paths.concat(Object.keys(flat));
+      Object.keys(flat).forEach(addToPaths);
     }
   }
 
-  // Single nested paths (paths embedded under single nested subdocs) will
-  // be validated on their own when we call `validate()` on the subdoc itself.
-  // Re: gh-8468
-  paths = paths.filter(p => !doc.schema.singleNestedPaths.hasOwnProperty(p));
 
-  len = paths.length;
-  for (i = 0; i < len; ++i) {
-    const path = paths[i];
+  for (const path of paths) {
+    // Single nested paths (paths embedded under single nested subdocs) will
+    // be validated on their own when we call `validate()` on the subdoc itself.
+    // Re: gh-8468
+    if (doc.schema.singleNestedPaths.hasOwnProperty(path)) {
+        paths.delete(path);
+        continue;
+    }
     const _pathType = doc.schema.path(path);
     if (!_pathType || !_pathType.$isSchemaMap) {
       continue;
@@ -2185,11 +2187,11 @@ function _getPathsToValidate(doc) {
       continue;
     }
     for (const key of val.keys()) {
-      paths.push(path + '.' + key);
+      paths.add(path + '.' + key);
     }
   }
 
-  paths = Array.from(new Set(paths));
+  paths = Array.from(paths);
   return [paths, skipSchemaValidators];
 }
 

From 01fd34f1a4406559f15e2aec20b36b42eef043ad Mon Sep 17 00:00:00 2001
From: Richard Bateman <taxilian@gmail.com>
Date: Tue, 28 Jan 2020 16:41:36 -0700
Subject: [PATCH 0444/2348] Fix lint issues

---
 lib/document.js                | 24 +++++++++++-------------
 lib/error/parallelValidate.js  |  4 ++--
 lib/schema.js                  |  2 +-
 lib/schema/SingleNestedPath.js | 16 ++++++++--------
 lib/schema/documentarray.js    |  6 +++---
 lib/schematype.js              |  2 +-
 6 files changed, 26 insertions(+), 28 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index fbee7b187b4..fdc6da4e626 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2079,8 +2079,6 @@ function _evaluateRequiredFunctions(doc) {
  */
 
 function _getPathsToValidate(doc) {
-  let i;
-  let len;
   const skipSchemaValidators = {};
 
   _evaluateRequiredFunctions(doc);
@@ -2110,13 +2108,13 @@ function _getPathsToValidate(doc) {
       // subdoc
       for (const p of paths) {
         if (p === null || p.startsWith(subdoc.$basePath + '.')) {
-            paths.delete(p);
+          paths.delete(p);
         }
       }
 
       if (doc.isModified(subdoc.$basePath, modifiedPaths) &&
-              !doc.isDirectModified(subdoc.$basePath) &&
-              !doc.$isDefault(subdoc.$basePath)) {
+            !doc.isDirectModified(subdoc.$basePath) &&
+            !doc.$isDefault(subdoc.$basePath)) {
         paths.add(subdoc.$basePath);
 
         skipSchemaValidators[subdoc.$basePath] = true;
@@ -2174,8 +2172,8 @@ function _getPathsToValidate(doc) {
     // be validated on their own when we call `validate()` on the subdoc itself.
     // Re: gh-8468
     if (doc.schema.singleNestedPaths.hasOwnProperty(path)) {
-        paths.delete(path);
-        continue;
+      paths.delete(path);
+      continue;
     }
     const _pathType = doc.schema.path(path);
     if (!_pathType || !_pathType.$isSchemaMap) {
@@ -2214,10 +2212,10 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       ('validateModifiedOnly' in options);
 
   const saveDeepStacktrace = (
-        options && 
-        (typeof options === 'object') &&
-        !!options['deepStackTrace'])
-     || !!this.schema.options.deepStackTrace;
+    options &&
+      (typeof options === 'object') &&
+      !!options['deepStackTrace'])
+      || !!this.schema.options.deepStackTrace;
   const parentStack = saveDeepStacktrace && options &&
       (typeof options === 'object') &&
       options.parentStack || [];
@@ -2308,8 +2306,8 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     validated[path] = true;
     total++;
 
-    let stackToHere = saveDeepStacktrace ?
-        [(new Error().stack), path].concat(parentStack) : void 0;
+    const stackToHere = saveDeepStacktrace ?
+      [(new Error().stack), path].concat(parentStack) : void 0;
 
     process.nextTick(function() {
       const p = _this.schema.path(path);
diff --git a/lib/error/parallelValidate.js b/lib/error/parallelValidate.js
index c0fedc88224..a9e398798a1 100644
--- a/lib/error/parallelValidate.js
+++ b/lib/error/parallelValidate.js
@@ -18,8 +18,8 @@ function ParallelValidateError(doc, opts) {
   MongooseError.call(this, msg + doc._id);
   this.name = 'ParallelValidateError';
   if (opts && opts.parentStack) {
-      // Provide a full async stack, most recent first
-      this.stack = this.stack + "\n\n" + opts.parentStack.join('\n\n');
+    // Provide a full async stack, most recent first
+    this.stack = this.stack + '\n\n' + opts.parentStack.join('\n\n');
   }
   // You need to know to look for this, but having it can be very helpful
   // for tracking down issues when combined with the deepStackTrace schema
diff --git a/lib/schema.js b/lib/schema.js
index e6b0c934c21..1498c61e403 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -404,7 +404,7 @@ Schema.prototype.defaultOptions = function(options) {
     capped: false, // { size, max, autoIndexId }
     // Setting to true may help with debugging but will have performance
     // consequences
-    deepStackTrace: false, 
+    deepStackTrace: false,
     versionKey: '__v',
     discriminatorKey: '__t',
     minimize: true,
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 887f0f496ad..83e5dc19bdc 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -238,13 +238,13 @@ SingleNestedPath.prototype.doValidate = function(value, fn, scope, options) {
       value = new Constructor(value, null, scope);
     }
     try {
-        return value.validate(fn);
+      return value.validate(fn);
     } catch (err) {
-        // Save the parent stack on the error
-        if (options.parentStack) {
-            err.parentStack = options.parentStack;
-        }
-        throw err;
+      // Save the parent stack on the error
+      if (options.parentStack) {
+        err.parentStack = options.parentStack;
+      }
+      throw err;
     }
   }
   const parentStack = options && options.parentStack;
@@ -258,8 +258,8 @@ SingleNestedPath.prototype.doValidate = function(value, fn, scope, options) {
     }
 
     value.validate(fn, {
-        deepStackTrace: !!parentStack,
-        parentStack: parentStack,
+      deepStackTrace: !!parentStack,
+      parentStack: parentStack,
     });
   }, scope, options);
 };
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index b23d10ee307..b2d33b9b182 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -252,9 +252,9 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
       }
 
       doc.$__validate(null, {
-          parentStack: options && options.parentStack,
-          deepStackTrace: !!(options && options.parentStack)
-        }, callback);
+        parentStack: options && options.parentStack,
+        deepStackTrace: !!(options && options.parentStack)
+      }, callback);
     }
   }
 };
diff --git a/lib/schematype.js b/lib/schematype.js
index fab04d90d42..29e5a9089c9 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1061,7 +1061,7 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
       err = new ErrorConstructor(validatorProperties);
       err[validatorErrorSymbol] = true;
       if (options && options.parentStack) {
-          error.parentStack = options.parentStack;
+        err.parentStack = options.parentStack;
       }
       immediate(function() {
         fn(err);

From 27f45a5cf1fe2539427900a5da54be8327e14a98 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Tue, 28 Jan 2020 18:12:41 -0600
Subject: [PATCH 0445/2348] Add test for issue described in
 Automattic/mongoose#8543

---
 test/model.discriminator.test.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 9a89de40c2d..852ab95b42e 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1329,6 +1329,13 @@ describe('model', function() {
       // Delete every model
       afterEach(function() { mongoose.deleteModel(/.+/); });
 
+      it('does not modify _id path of the passed in schema the _id is not auto generated', function() {
+        const model = mongoose.model('Model', new mongoose.Schema({ _id: Number }));
+        const passedInSchema = new mongoose.Schema({});
+        model.discriminator('Discrimintaor', passedInSchema);
+        assert.equal(passedInSchema.path('_id').instance, 'ObjectID');
+      });
+
       function throwErrorOnClone() { throw new Error('clone() was called on the unrelated schema'); };
 
       it('when the base schema has an _id that is not auto generated', function() {

From 834200d8689504f49f2b510270b61136090f3a37 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Wed, 29 Jan 2020 19:18:02 -0600
Subject: [PATCH 0446/2348] Fix minor issues and add test cases for #8543

---
 lib/schema/SingleNestedPath.js       |   2 +-
 test/docs/discriminators.test.js     |   4 +-
 test/model.discriminator.test.js     |   6 +-
 test/schema.singlenestedpath.test.js | 146 +++++++++++++++++++++++++++
 4 files changed, 152 insertions(+), 6 deletions(-)
 create mode 100644 test/schema.singlenestedpath.test.js

diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index a33d65bf74c..13144ccdf5e 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -291,7 +291,7 @@ SingleNestedPath.prototype.doValidateSync = function(value, scope, options) {
  */
 
 SingleNestedPath.prototype.discriminator = function(name, schema, value) {
-  discriminator(this.caster, name, schema, value);
+  schema = discriminator(this.caster, name, schema, value);
 
   this.caster.discriminators[name] = _createConstructor(schema, this.caster);
 
diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index 829976dbf82..76ced02bd1a 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -213,8 +213,8 @@ describe('discriminator docs', function () {
     var event1 = new ClickedLinkEvent({ _id: 'custom id', time: '4pm' });
     // Woops, clickedLinkSchema overwrites the `time` path, but **not**
     // the `_id` path because that was implicitly added.
-    assert.ok(typeof event1._id === 'string');
-    assert.ok(typeof event1.time === 'string');
+    assert.strictEqual(typeof event1._id, 'string');
+    assert.strictEqual(typeof event1.time, 'string');
 
     // acquit:ignore:start
     done();
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 852ab95b42e..5b837e76650 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -312,7 +312,7 @@ describe('model', function() {
       });
 
       it('inherits statics', function(done) {
-        assert.strictEqual(Employee.findByGender, EmployeeSchema.statics.findByGender);
+        assert.strictEqual(Employee.findByGender, PersonSchema.statics.findByGender);
         assert.strictEqual(Employee.findByDepartment, EmployeeSchema.statics.findByDepartment);
         assert.equal(Person.findByDepartment, undefined);
         done();
@@ -1329,7 +1329,7 @@ describe('model', function() {
       // Delete every model
       afterEach(function() { mongoose.deleteModel(/.+/); });
 
-      it('does not modify _id path of the passed in schema the _id is not auto generated', function() {
+      it('does not modify _id path of the passed in schema the _id is not auto generated (gh-8543)', function() {
         const model = mongoose.model('Model', new mongoose.Schema({ _id: Number }));
         const passedInSchema = new mongoose.Schema({});
         model.discriminator('Discrimintaor', passedInSchema);
@@ -1338,7 +1338,7 @@ describe('model', function() {
 
       function throwErrorOnClone() { throw new Error('clone() was called on the unrelated schema'); };
 
-      it('when the base schema has an _id that is not auto generated', function() {
+      it('when the base schema has an _id that is not auto generated (gh-8543) (gh-8546)', function() {
         const unrelatedSchema = new mongoose.Schema({});
         unrelatedSchema.clone = throwErrorOnClone;
         mongoose.model('UnrelatedModel', unrelatedSchema);
diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
new file mode 100644
index 00000000000..6d2757eade8
--- /dev/null
+++ b/test/schema.singlenestedpath.test.js
@@ -0,0 +1,146 @@
+'use strict';
+
+/**
+ * Module dependencies.
+ */
+
+const mongoose = require('./common').mongoose;
+
+const assert = require('assert');
+
+const Schema = mongoose.Schema;
+
+describe('SingleNestedPath', function() {
+  describe('discriminator()', function() {
+    describe('recursive nested discriminators', function() {
+      it('allow multiple levels of data in the schema', function() {
+        const singleEventSchema = new Schema({
+          message: String,
+        }, { _id: false, discriminatorKey: 'kind' });
+
+        const subEventSchema = new Schema({
+          sub_events: [singleEventSchema]
+        }, {_id: false});
+
+        subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
+          
+        let currentEventLevel = subEventSchema;
+        for (let i = 0; i < 5; i++) {
+          const subEventSchemaDiscriminators = currentEventLevel.path('sub_events').schema.discriminators;
+          assert.ok(subEventSchemaDiscriminators);
+          assert.ok(subEventSchemaDiscriminators.SubEvent)
+          currentEventLevel = subEventSchemaDiscriminators.SubEvent;
+        }
+      });
+
+      it('allow multiple levels of data in a document', function() {
+        const singleEventSchema = new Schema({
+          message: String,
+        }, { _id: false, discriminatorKey: 'kind' });
+
+        const subEventSchema = new Schema({
+          sub_events: [singleEventSchema]
+        }, {_id: false});
+
+        subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
+
+        const SubEvent = mongoose.model('MultiLevelDataDoc', subEventSchema);
+        const multiLevel = {
+          // To create a recursive document, the schema was modified, so kind & message are added
+          kind: 'SubEvent',
+          message: 'level 1',
+          sub_events: [{ 
+            kind: 'SubEvent', 
+            message: 'level 2',
+            sub_events: [{ 
+              kind: 'SubEvent',
+              message: 'level 3',
+              sub_events: [{ 
+                kind: 'SubEvent', 
+                message: 'level 4',
+                sub_events: [{ 
+                  kind: 'SubEvent', 
+                  message: 'level 5',
+                  sub_events: [], 
+                }], 
+              }],
+            }],
+          }]
+        };
+        const subEvent = SubEvent(multiLevel);
+        
+        assert.deepStrictEqual(multiLevel, subEvent.toJSON());
+      });
+
+      it('allow multiple levels of data in the schema when the base schema has _id without auto', function() {
+        const singleEventSchema = new Schema({
+          _id: { type: Number, required: true },
+          message: String,
+        }, { discriminatorKey: 'kind' });
+          
+        const subEventSchema = new Schema({
+          sub_events: [singleEventSchema]
+        });
+
+        subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
+        
+        // To create a recursive document, the schema was modified, so the _id property is now a number
+        assert.equal(subEventSchema.path('_id').instance, 'Number');
+          
+        let currentEventLevel = subEventSchema;
+        for (let i = 0; i < 5; i++) {
+          const subEventSchemaDiscriminators = currentEventLevel.path('sub_events').schema.discriminators;
+          assert.ok(subEventSchemaDiscriminators);
+          assert.ok(subEventSchemaDiscriminators.SubEvent)
+          currentEventLevel = subEventSchemaDiscriminators.SubEvent;
+          assert.equal(currentEventLevel.path('_id').instance, 'Number');
+        }
+      });
+
+      it('allow multiple levels of data in a document when the base schema has _id without auto', function() {
+        const singleEventSchema = new Schema({
+          _id: { type: Number, required: true },
+          message: String,
+        }, { discriminatorKey: 'kind' });
+          
+        const subEventSchema = new Schema({
+          sub_events: [singleEventSchema]
+        });
+
+        subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
+        
+        const SubEvent = mongoose.model('MultiLevelDataWithIdDoc', subEventSchema);
+        const multiLevel = {
+          // To create a recursive document, the schema was modified, so kind & message are added & _id is now Number
+          _id: 1,
+          kind: 'SubEvent',
+          message: 'level 1',
+          sub_events: [{
+            _id: 1,
+            kind: 'SubEvent', 
+            message: 'level 2',
+            sub_events: [{ 
+              _id: 1,
+              kind: 'SubEvent',
+              message: 'level 3',
+              sub_events: [{ 
+                _id: 1,
+                kind: 'SubEvent', 
+                message: 'level 4',
+                sub_events: [{ 
+                  _id: 1,
+                  kind: 'SubEvent', 
+                  message: 'level 5',
+                  sub_events: [], 
+                }], 
+              }],
+            }],
+          }]
+        };
+        const subEvent = SubEvent(multiLevel);
+
+        assert.deepStrictEqual(multiLevel, subEvent.toJSON());
+      });
+    })
+  });
+});
\ No newline at end of file

From 2389ea40280127827be9f541c72928f8fe4cb008 Mon Sep 17 00:00:00 2001
From: Sam <42203151+samgladstone@users.noreply.github.com>
Date: Wed, 29 Jan 2020 19:22:50 -0600
Subject: [PATCH 0447/2348] lint

---
 test/schema.singlenestedpath.test.js | 54 ++++++++++++++--------------
 1 file changed, 27 insertions(+), 27 deletions(-)

diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
index 6d2757eade8..83c21a11dd8 100644
--- a/test/schema.singlenestedpath.test.js
+++ b/test/schema.singlenestedpath.test.js
@@ -23,12 +23,12 @@ describe('SingleNestedPath', function() {
         }, {_id: false});
 
         subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
-          
+
         let currentEventLevel = subEventSchema;
         for (let i = 0; i < 5; i++) {
           const subEventSchemaDiscriminators = currentEventLevel.path('sub_events').schema.discriminators;
           assert.ok(subEventSchemaDiscriminators);
-          assert.ok(subEventSchemaDiscriminators.SubEvent)
+          assert.ok(subEventSchemaDiscriminators.SubEvent);
           currentEventLevel = subEventSchemaDiscriminators.SubEvent;
         }
       });
@@ -49,26 +49,26 @@ describe('SingleNestedPath', function() {
           // To create a recursive document, the schema was modified, so kind & message are added
           kind: 'SubEvent',
           message: 'level 1',
-          sub_events: [{ 
-            kind: 'SubEvent', 
+          sub_events: [{
+            kind: 'SubEvent',
             message: 'level 2',
-            sub_events: [{ 
+            sub_events: [{
               kind: 'SubEvent',
               message: 'level 3',
-              sub_events: [{ 
-                kind: 'SubEvent', 
+              sub_events: [{
+                kind: 'SubEvent',
                 message: 'level 4',
-                sub_events: [{ 
-                  kind: 'SubEvent', 
+                sub_events: [{
+                  kind: 'SubEvent',
                   message: 'level 5',
-                  sub_events: [], 
-                }], 
+                  sub_events: [],
+                }],
               }],
             }],
           }]
         };
         const subEvent = SubEvent(multiLevel);
-        
+
         assert.deepStrictEqual(multiLevel, subEvent.toJSON());
       });
 
@@ -77,21 +77,21 @@ describe('SingleNestedPath', function() {
           _id: { type: Number, required: true },
           message: String,
         }, { discriminatorKey: 'kind' });
-          
+
         const subEventSchema = new Schema({
           sub_events: [singleEventSchema]
         });
 
         subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
-        
+
         // To create a recursive document, the schema was modified, so the _id property is now a number
         assert.equal(subEventSchema.path('_id').instance, 'Number');
-          
+
         let currentEventLevel = subEventSchema;
         for (let i = 0; i < 5; i++) {
           const subEventSchemaDiscriminators = currentEventLevel.path('sub_events').schema.discriminators;
           assert.ok(subEventSchemaDiscriminators);
-          assert.ok(subEventSchemaDiscriminators.SubEvent)
+          assert.ok(subEventSchemaDiscriminators.SubEvent);
           currentEventLevel = subEventSchemaDiscriminators.SubEvent;
           assert.equal(currentEventLevel.path('_id').instance, 'Number');
         }
@@ -102,13 +102,13 @@ describe('SingleNestedPath', function() {
           _id: { type: Number, required: true },
           message: String,
         }, { discriminatorKey: 'kind' });
-          
+
         const subEventSchema = new Schema({
           sub_events: [singleEventSchema]
         });
 
         subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
-        
+
         const SubEvent = mongoose.model('MultiLevelDataWithIdDoc', subEventSchema);
         const multiLevel = {
           // To create a recursive document, the schema was modified, so kind & message are added & _id is now Number
@@ -117,22 +117,22 @@ describe('SingleNestedPath', function() {
           message: 'level 1',
           sub_events: [{
             _id: 1,
-            kind: 'SubEvent', 
+            kind: 'SubEvent',
             message: 'level 2',
-            sub_events: [{ 
+            sub_events: [{
               _id: 1,
               kind: 'SubEvent',
               message: 'level 3',
-              sub_events: [{ 
+              sub_events: [{
                 _id: 1,
-                kind: 'SubEvent', 
+                kind: 'SubEvent',
                 message: 'level 4',
-                sub_events: [{ 
+                sub_events: [{
                   _id: 1,
-                  kind: 'SubEvent', 
+                  kind: 'SubEvent',
                   message: 'level 5',
-                  sub_events: [], 
-                }], 
+                  sub_events: [],
+                }],
               }],
             }],
           }]
@@ -141,6 +141,6 @@ describe('SingleNestedPath', function() {
 
         assert.deepStrictEqual(multiLevel, subEvent.toJSON());
       });
-    })
+    });
   });
 });
\ No newline at end of file

From 867cb5f95e7074983b546d72c1c43d8b15a87c9d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Jan 2020 13:38:40 -0500
Subject: [PATCH 0448/2348] fix(connection): allow calling initial
 `mongoose.connect()` after connection helpers on the same tick

Fix #8534
Re: #8319
---
 lib/connection.js | 46 ++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 40 insertions(+), 6 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index b2bf74d59f8..688d49b8c1e 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -13,12 +13,15 @@ const PromiseProvider = require('./promise_provider');
 const TimeoutError = require('./error/timeout');
 const applyPlugins = require('./helpers/schema/applyPlugins');
 const get = require('./helpers/get');
+const immediate = require('./helpers/immediate');
 const mongodb = require('mongodb');
 const pkg = require('../package.json');
 const utils = require('./utils');
 
 const parseConnectionString = require('mongodb/lib/core').parseConnectionString;
 
+let id = 0;
+
 /*!
  * A list of authentication mechanisms that don't require a password for authentication.
  * This is used by the authMechanismDoesNotRequirePassword method.
@@ -62,6 +65,7 @@ function Connection(base) {
   this._closeCalled = false;
   this._hasOpened = false;
   this.plugins = [];
+  this.id = id++;
 }
 
 /*!
@@ -210,6 +214,27 @@ Connection.prototype.name;
 
 Connection.prototype.models;
 
+/**
+ * A number identifier for this connection. Used for debugging when
+ * you have [multiple connections](/docs/connections.html#multiple_connections).
+ *
+ * ####Example
+ *
+ *     // The default connection has `id = 0`
+ *     mongoose.connection.id; // 0
+ *
+ *     // If you create a new connection, Mongoose increments id
+ *     const conn = mongoose.createConnection();
+ *     conn.id; // 1
+ *
+ * @property id
+ * @memberOf Connection
+ * @instance
+ * @api public
+ */
+
+Connection.prototype.id;
+
 /**
  * The plugins that will be applied to all models created on this connection.
  *
@@ -442,14 +467,23 @@ function _wrapConnHelper(fn) {
     const argsWithoutCb = typeof cb === 'function' ?
       Array.prototype.slice.call(arguments, 0, arguments.length - 1) :
       Array.prototype.slice.call(arguments);
+    const disconnectedError = new MongooseError('Connection ' + this.id +
+      ' was disconnected when calling `' + fn.name + '`');
     return utils.promiseOrCallback(cb, cb => {
-      if (this.readyState === STATES.connecting) {
-        this.once('open', function() {
+      // Make it ok to call collection helpers before `mongoose.connect()`
+      // as long as `mongoose.connect()` is called on the same tick.
+      // Re: gh-8534
+      immediate(() => {
+        if (this.readyState === STATES.connecting) {
+          this.once('open', function() {
+            fn.apply(this, argsWithoutCb.concat([cb]));
+          });
+        } else if (this.readyState === STATES.disconnected && this.db == null) {
+          cb(disconnectedError);
+        } else {
           fn.apply(this, argsWithoutCb.concat([cb]));
-        });
-      } else {
-        fn.apply(this, argsWithoutCb.concat([cb]));
-      }
+        }
+      });
     });
   };
 }

From 3f1f1de70b00e84320cdb2cafd983e707d0d39a9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Jan 2020 16:50:03 -0500
Subject: [PATCH 0449/2348] fix: remove discriminator schema `_id` before
 merging if base schema has custom _id without calling `merge()`

Fix #8546
Re: #8543
---
 lib/helpers/model/discriminator.js | 5 ++---
 test/model.discriminator.test.js   | 2 +-
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index 64765f51dbf..11867d34da5 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -72,8 +72,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     if (baseSchema.paths._id &&
         baseSchema.paths._id.options &&
         !baseSchema.paths._id.options.auto) {
-      delete schema.paths._id;
-      delete schema.tree._id;
+      schema.remove('_id');
     }
 
     // Find conflicting paths: if something is a path in the base schema
@@ -88,7 +87,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     }
 
     utils.merge(schema, baseSchema, {
-      omit: { discriminators: true },
+      omit: { discriminators: true, base: true },
       omitNested: conflictingPaths.reduce((cur, path) => {
         cur['tree.' + path] = true;
         return cur;
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 5b837e76650..4bb6f86dc9b 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1333,7 +1333,7 @@ describe('model', function() {
         const model = mongoose.model('Model', new mongoose.Schema({ _id: Number }));
         const passedInSchema = new mongoose.Schema({});
         model.discriminator('Discrimintaor', passedInSchema);
-        assert.equal(passedInSchema.path('_id').instance, 'ObjectID');
+        assert.equal(passedInSchema.path('_id').instance, 'Number');
       });
 
       function throwErrorOnClone() { throw new Error('clone() was called on the unrelated schema'); };

From 047fc94c1b1ef51a4f789dc821b147850ad8e088 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jan 2020 10:47:59 -0500
Subject: [PATCH 0450/2348] fix(document): allow calling `validate()` multiple
 times in parallel on subdocs to avoid errors if Mongoose double-validates

Fix #8539
Re: #8548
---
 lib/document.js                | 19 ++++---------------
 lib/error/parallelValidate.js  | 10 +---------
 lib/schema.js                  |  3 ---
 lib/schema/SingleNestedPath.js | 16 ++--------------
 lib/schema/documentarray.js    |  7 ++-----
 lib/schematype.js              |  6 ------
 test/document.test.js          | 19 +++++++++++++++++--
 7 files changed, 26 insertions(+), 54 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index fdc6da4e626..bcc2cdff695 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2029,7 +2029,9 @@ Document.prototype.isDirectSelected = function isDirectSelected(path) {
 Document.prototype.validate = function(pathsToValidate, options, callback) {
   let parallelValidate;
 
-  if (this.$__.validating) {
+  if (this.ownerDocument != null) {
+    // Skip parallel validate check for subdocuments
+  } else if (this.$__.validating) {
     parallelValidate = new ParallelValidateError(this, {
       parentStack: options && options.parentStack,
       conflictStack: this.$__.validating.stack
@@ -2211,15 +2213,6 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       (typeof options === 'object') &&
       ('validateModifiedOnly' in options);
 
-  const saveDeepStacktrace = (
-    options &&
-      (typeof options === 'object') &&
-      !!options['deepStackTrace'])
-      || !!this.schema.options.deepStackTrace;
-  const parentStack = saveDeepStacktrace && options &&
-      (typeof options === 'object') &&
-      options.parentStack || [];
-
   let shouldValidateModifiedOnly;
   if (hasValidateModifiedOnlyOption) {
     shouldValidateModifiedOnly = !!options.validateModifiedOnly;
@@ -2306,9 +2299,6 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     validated[path] = true;
     total++;
 
-    const stackToHere = saveDeepStacktrace ?
-      [(new Error().stack), path].concat(parentStack) : void 0;
-
     process.nextTick(function() {
       const p = _this.schema.path(path);
 
@@ -2337,8 +2327,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
 
       const doValidateOptions = {
         skipSchemaValidators: skipSchemaValidators[path],
-        path: path,
-        parentStack: stackToHere
+        path: path
       };
       p.doValidate(val, function(err) {
         if (err && (!p.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
diff --git a/lib/error/parallelValidate.js b/lib/error/parallelValidate.js
index a9e398798a1..c5cc83b89fa 100644
--- a/lib/error/parallelValidate.js
+++ b/lib/error/parallelValidate.js
@@ -13,18 +13,10 @@ const MongooseError = require('./mongooseError');
  * @api private
  */
 
-function ParallelValidateError(doc, opts) {
+function ParallelValidateError(doc) {
   const msg = 'Can\'t validate() the same doc multiple times in parallel. Document: ';
   MongooseError.call(this, msg + doc._id);
   this.name = 'ParallelValidateError';
-  if (opts && opts.parentStack) {
-    // Provide a full async stack, most recent first
-    this.stack = this.stack + '\n\n' + opts.parentStack.join('\n\n');
-  }
-  // You need to know to look for this, but having it can be very helpful
-  // for tracking down issues when combined with the deepStackTrace schema
-  // option
-  this.conflictStack = opts && opts.conflictStack;
 }
 
 /*!
diff --git a/lib/schema.js b/lib/schema.js
index 1498c61e403..06cd1d4341b 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -402,9 +402,6 @@ Schema.prototype.defaultOptions = function(options) {
     strict: 'strict' in baseOptions ? baseOptions.strict : true,
     bufferCommands: true,
     capped: false, // { size, max, autoIndexId }
-    // Setting to true may help with debugging but will have performance
-    // consequences
-    deepStackTrace: false,
     versionKey: '__v',
     discriminatorKey: '__t',
     minimize: true,
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index b3eb5c45057..9ac29710ec6 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -237,17 +237,8 @@ SingleNestedPath.prototype.doValidate = function(value, fn, scope, options) {
     if (!(value instanceof Constructor)) {
       value = new Constructor(value, null, scope);
     }
-    try {
-      return value.validate(fn);
-    } catch (err) {
-      // Save the parent stack on the error
-      if (options.parentStack) {
-        err.parentStack = options.parentStack;
-      }
-      throw err;
-    }
+    return value.validate(fn);
   }
-  const parentStack = options && options.parentStack;
 
   SchemaType.prototype.doValidate.call(this, value, function(error) {
     if (error) {
@@ -257,10 +248,7 @@ SingleNestedPath.prototype.doValidate = function(value, fn, scope, options) {
       return fn(null);
     }
 
-    value.validate(fn, {
-      deepStackTrace: !!parentStack,
-      parentStack: parentStack,
-    });
+    value.validate(fn);
   }, scope, options);
 };
 
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index b2d33b9b182..3ec0e3cc27d 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -197,7 +197,7 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
 
   const _this = this;
   try {
-    SchemaType.prototype.doValidate.call(this, array, cb, scope, options);
+    SchemaType.prototype.doValidate.call(this, array, cb, scope);
   } catch (err) {
     err.$isArrayValidatorError = true;
     return fn(err);
@@ -251,10 +251,7 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
         doc = array[i] = new Constructor(doc, array, undefined, undefined, i);
       }
 
-      doc.$__validate(null, {
-        parentStack: options && options.parentStack,
-        deepStackTrace: !!(options && options.parentStack)
-      }, callback);
+      doc.$__validate(callback);
     }
   }
 };
diff --git a/lib/schematype.js b/lib/schematype.js
index 29e5a9089c9..35c028fe9fc 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1060,9 +1060,6 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
       const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
       err = new ErrorConstructor(validatorProperties);
       err[validatorErrorSymbol] = true;
-      if (options && options.parentStack) {
-        err.parentStack = options.parentStack;
-      }
       immediate(function() {
         fn(err);
       });
@@ -1104,9 +1101,6 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
           if (error.message) {
             validatorProperties.message = error.message;
           }
-          if (options && options.parentStack) {
-            validatorProperties.deepStack = options.parentStack;
-          }
         }
         if (ok != null && typeof ok.then === 'function') {
           ok.then(
diff --git a/test/document.test.js b/test/document.test.js
index 72c01900d9a..be67a3625e1 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -585,8 +585,8 @@ describe('document', function() {
     const keySchema = Schema({ql: [questionSchema]}, {_id: false, id: false});
     const Model = db.model('gh8468-2', Schema({
       name: String,
-      keys: [keySchema],
-    }, {deepStackTrace: true}));
+      keys: [keySchema]
+    }));
     const doc = new Model({
       name: 'test',
       keys: [
@@ -8632,4 +8632,19 @@ describe('document', function() {
     const doc = new Model({ arr: [{}, {}, {}] });
     assert.deepEqual(doc.toObject().arr.map(v => v.val), [1, 2, 3]);
   });
+
+  it('can call subdocument validate multiple times in parallel (gh-8539)', function() {
+    const schema = Schema({
+      arr: [{ val: String }],
+      single: Schema({ val: String })
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = new Model({ arr: [{ val: 'test' }], single: { val: 'test' } });
+
+      yield [doc.arr[0].validate(), doc.arr[0].validate()];
+      yield [doc.single.validate(), doc.single.validate()];
+    });
+  });
 });

From 2379a4284dbe30d3ef67267bad8bbe83fc353f09 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jan 2020 15:06:15 -0500
Subject: [PATCH 0451/2348] fix(connection): throw helpful error when callback
 param to `mongoose.connect()` or `mongoose.createConnection()` is not a
 function

Fix #8556
---
 lib/connection.js | 6 ++++++
 lib/index.js      | 6 +++---
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 688d49b8c1e..f249b8aaf75 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -579,6 +579,12 @@ Connection.prototype.openUri = function(uri, options, callback) {
       '`mongoose.connect()` or `mongoose.createConnection()` is a string.');
   }
 
+  if (callback != null && typeof callback !== 'function') {
+    throw new MongooseError('3rd parameter to `mongoose.connect()` or ' +
+      '`mongoose.createConnection()` must be a function, got "' +
+      typeof callback + '"');
+  }
+
   const Promise = PromiseProvider.get();
   const _this = this;
 
diff --git a/lib/index.js b/lib/index.js
index c1528ed6b14..67aa43acd6e 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -15,6 +15,7 @@ if (global.MONGOOSE_DRIVER_PATH) {
   require('./driver').set(require('./drivers/node-mongodb-native'));
 }
 
+const Document = require('./document');
 const Schema = require('./schema');
 const SchemaType = require('./schematype');
 const SchemaTypes = require('./schema/index');
@@ -24,7 +25,6 @@ const VALID_OPTIONS = require('./validoptions');
 const Types = require('./types');
 const Query = require('./query');
 const Model = require('./model');
-const Document = require('./document');
 const applyPlugins = require('./helpers/schema/applyPlugins');
 const get = require('./helpers/get');
 const legacyPluralize = require('mongoose-legacy-pluralize');
@@ -326,10 +326,10 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @return {Promise} resolves to `this` if connection succeeded
  */
 
-Mongoose.prototype.connect = function() {
+Mongoose.prototype.connect = function(uri, options, callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
   const conn = _mongoose.connection;
-  return conn.openUri(arguments[0], arguments[1], arguments[2]).then(() => _mongoose);
+  return conn.openUri(uri, options, callback).then(() => _mongoose);
 };
 
 /**

From 4b72a6f5c2dd3be3696ffcd19257488ce65f762f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jan 2020 16:03:19 -0500
Subject: [PATCH 0452/2348] docs: add "built with mongoose" page

Fix #8540
---
 docs/built-with-mongoose.pug | 54 ++++++++++++++++++++++++++++++++++++
 docs/layout.pug              |  2 ++
 docs/source/index.js         |  1 +
 3 files changed, 57 insertions(+)
 create mode 100644 docs/built-with-mongoose.pug

diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
new file mode 100644
index 00000000000..8c446bf65d9
--- /dev/null
+++ b/docs/built-with-mongoose.pug
@@ -0,0 +1,54 @@
+extends layout
+
+block content
+  :markdown
+    ## Built With Mongoose
+
+    According to [GitHub](https://github.com/Automattic/mongoose), there are
+    over 870,000 projects that depend on Mongoose. Here are a few of
+    our favorite apps that are built with Mongoose.
+
+    <div style="position: relative; height: 100px">
+      <div style="position: absolute; width: 100px; height: 100px">
+        <a href="https://sixplus.com">
+          <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1452784634/wipgioqzev0omt4ezsay.jpg">
+        </a>
+      </div>
+      <div style="position: absolute; left: 110px">
+        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://sixplus.com/">SixPlus</a></h3>
+        SixPlus is an online marketplace for corporate event professionals to
+        book private dining spaces in restaurants and hotels across the US.
+        You can book your next company event at venues like <a href="https://sixplus.com/venue/refinery-rooftop-at-refinery-hotel/">Refinery Rooftop</a> or
+        <a href="https://sixplus.com/venue/good-behavior-at-made-hotel/">Good Behavior</a> on SixPlus.
+      </div>
+    </div>
+
+    <div style="position: relative; height: 100px; margin-top: 1em;">
+      <div style="position: absolute; width: 100px; height: 100px">
+        <a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
+          <img src="https://res-1.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1503059272/h8tzm8hqqabjknhj9cts.png">
+        </a>
+      </div>
+      <div style="position: absolute; left: 110px">
+        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">Payment Ninja</a></h3>
+        Payment Ninja is an online payment gateway that lets you save up to
+        50% on payment processing over processors like PayPal and Stripe.
+      </div>
+    </div>
+
+    <div style="position: relative; height: 100px; margin-top: 1em;">
+      <div style="position: absolute; width: 100px; height: 100px">
+        <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
+          <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1426108234/rb6qztygayubxme8f4tx.png">
+        </a>
+      </div>
+      <div style="position: absolute; left: 110px">
+        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">Mixmax</a></h3>
+        Mixmax is a app that sends engaging emails with instant scheduling, free unlimited email tracking, polls, and surveys right in Gmail.
+      </div>
+    </div>
+
+    ## Add Your Own
+
+    Have an app that you built with Mongoose that you want to feature here?
+    Let's talk! [DM Mongoose on Twitter](https://twitter.com/mongoosejs).
\ No newline at end of file
diff --git a/docs/layout.pug b/docs/layout.pug
index fb6f9455bdd..874802463d4 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -115,6 +115,8 @@ html(lang='en')
                 a.pure-menu-link(href="/docs/further_reading.html") Further Reading
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/enterprise.html") For Enterprise
+              li.pure-menu-item
+                a.pure-menu-link(href="/docs/built-with-mongoose.html") Built with Mongoose
             div.cpc-ad
               <script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script>
         .container
diff --git a/docs/source/index.js b/docs/source/index.js
index 6687cf57065..9a78297a33e 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -33,3 +33,4 @@ exports['docs/compatibility.pug'] = {
 };
 exports['docs/search.pug'] = { title: 'Search' };
 exports['docs/enterprise.pug'] = { title: 'Mongoose for Enterprise' };
+exports['docs/built-with-mongoose.pug'] = { title: 'Built with Mongoose' };
\ No newline at end of file

From ba79cca085461df9baaf352060d27e27e8d5d64e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jan 2020 17:06:42 -0500
Subject: [PATCH 0453/2348] chore: release 5.8.11

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 1f6b666ac2d..5989bf1c532 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.8.11 / 2020-01-31
+===================
+ * fix(document): allow calling `validate()` multiple times in parallel on subdocs to avoid errors if Mongoose double-validates [taxilian](https://github.com/taxilian) #8548 #8539
+ * fix(connection): allow calling initial `mongoose.connect()` after connection helpers on the same tick #8534
+ * fix(connection): throw helpful error when callback param to `mongoose.connect()` or `mongoose.createConnection()` is not a function #8556
+ * fix(drivers): avoid unnecessary caught error when importing #8528
+ * fix(discriminator): remove unnecessary `utils.merge()` [samgladstone](https://github.com/samgladstone) #8542
+ * docs: add "built with mongoose" page #8540
+
 5.8.10 / 2020-01-27
 ===================
  * perf(document): improve performance of document creation by skipping unnecessary split() calls #8533 [igrunert-atlassian](https://github.com/igrunert-atlassian)
diff --git a/package.json b/package.json
index 535270c38a3..193a81caabb 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.10",
+  "version": "5.8.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 19d2a471c6fc7175f2cfa00ac7d64bf0375091bc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 1 Feb 2020 13:12:37 -0500
Subject: [PATCH 0454/2348] chore: update opencollective sponsors

---
 index.pug | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.pug b/index.pug
index ad71ef80767..95ae293d79f 100644
--- a/index.pug
+++ b/index.pug
@@ -172,6 +172,9 @@ html(lang='en')
               <a href="https://www.dontpayfull.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F84c4ba80-1955-11e8-8343-278614155b3e.png&height=100" style="height:100px">
               </a>
+              <a href="https://frontendmasters.com/">
+                <img class="sponsor" src="https://images.opencollective.com/frontendmasters/0b9cda4/logo/256.png" style="height:100px">
+              </a>
               <a href="https://www.vpsserver.com/">
                 <img class="sponsor" src="https://pbs.twimg.com/profile_images/750300526538027008/jo7cFmU9_400x400.jpg" style="height: 100px">
               </a>
@@ -262,9 +265,6 @@ html(lang='en')
               <a href="https://www.crosswordsolver.com/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/crosswordsolver.png" style="height: 80px">
               </a>
-              <a href="https://vpnblackfriday.com/">
-                <img class="sponsor" src="https://images.opencollective.com/vpn-black-friday/2b3cf9c/logo.png" style="height: 100px">
-              </a>
               <a href="https://uk.edubirdie.com/">
                 <img class="sponsor" src="https://images.opencollective.com/uk-edubirdie-com/b1d51ab/logo.png" style="height: 100px">
               </a>

From 5b6e51f1e96919c9b5c60ada8798ed37f7143207 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 1 Feb 2020 14:25:35 -0500
Subject: [PATCH 0455/2348] feat(populate): support `skip` as top-level
 populate option

Re: #8445
---
 .../populate/getModelsMapForPopulate.js       |  4 +++
 lib/model.js                                  |  4 ++-
 lib/options/VirtualOptions.js                 | 12 ++++++++
 test/model.populate.test.js                   | 30 +++++++++++--------
 4 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index b7b5982cdf0..a60c0d558b6 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -102,6 +102,10 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         localField = virtualPrefix + virtual.options.localField;
       }
       count = virtual.options.count;
+
+      if (virtual.options.skip != null && !options.hasOwnProperty('skip')) {
+        options.skip = virtual.options.skip;
+      }
     } else {
       localField = options.path;
     }
diff --git a/lib/model.js b/lib/model.js
index b7c0b7ef6d1..6a567e3b1f1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4391,7 +4391,9 @@ function populate(model, docs, options, callback) {
 function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
   const subPopulate = utils.clone(mod.options.populate);
 
-  const queryOptions = Object.assign({}, mod.options.options);
+  const queryOptions = Object.assign({
+    skip: mod.options.skip
+  }, mod.options.options);
   if (mod.count) {
     delete queryOptions.skip;
   }
diff --git a/lib/options/VirtualOptions.js b/lib/options/VirtualOptions.js
index 0e755e9b163..917a9b94dc7 100644
--- a/lib/options/VirtualOptions.js
+++ b/lib/options/VirtualOptions.js
@@ -121,4 +121,16 @@ Object.defineProperty(VirtualOptions.prototype, 'match', opts);
 
 Object.defineProperty(VirtualOptions.prototype, 'options', opts);
 
+/**
+ * If true, add a `skip` to the query used to `populate()`.
+ *
+ * @api public
+ * @property skip
+ * @memberOf VirtualOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'skip', opts);
+
 module.exports = VirtualOptions;
\ No newline at end of file
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index bf12ec82e0f..b5eb2e1a9d3 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9028,17 +9028,17 @@ describe('model: populate:', function() {
     });
   });
 
-  it.skip('supports top-level skip and limit options (gh-8445)', function() {
-    const childSchema = Schema({ parentId: 'ObjectId', deleted: Boolean });
+  it('supports top-level skip and limit options (gh-8445)', function() {
+    const childSchema = Schema({ _id: Number, parentId: 'ObjectId' });
 
     const parentSchema = Schema({ name: String });
-    parentSchema.virtual('childCount', {
+    parentSchema.virtual('children', {
       ref: 'Child',
       localField: '_id',
       foreignField: 'parentId',
       justOne: false,
       skip: 1,
-      limit: 2
+      options: { limit: 2, sort: { _id: 1 } }
     });
 
     const Child = db.model('Child', childSchema);
@@ -9048,17 +9048,23 @@ describe('model: populate:', function() {
       const p = yield Parent.create({ name: 'test' });
 
       yield Child.create([
-        { parentId: p._id },
-        { parentId: p._id, deleted: true },
-        { parentId: p._id, deleted: false }
+        { _id: 1, parentId: p._id },
+        { _id: 2, parentId: p._id },
+        { _id: 3, parentId: p._id }
       ]);
 
-      let doc = yield Parent.findOne().populate('childCount');
-      assert.equal(doc.childCount, 2);
+      let doc = yield Parent.findOne().populate('children');
+      assert.deepEqual(doc.children.map(c => c._id), [2, 3]);
 
-      doc = yield Parent.findOne().
-        populate({ path: 'childCount', match: { deleted: true } });
-      assert.equal(doc.childCount, 1);
+      doc = yield Parent.findOne().populate({ path: 'children', skip: 2 });
+      assert.deepEqual(doc.children.map(c => c._id), [3]);
+
+      doc = yield Parent.findOne().populate({
+        path: 'children',
+        skip: 2,
+        options: { skip: 1 }
+      });
+      assert.deepEqual(doc.children.map(c => c._id), [2, 3]);
     });
   });
 

From b4fd66d8374bdc194db575b9d0094dbaabd673fc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 1 Feb 2020 15:35:04 -0500
Subject: [PATCH 0456/2348] feat(populate): support `limit` as top-level
 populate option

Fix #8445
---
 .../populate/getModelsMapForPopulate.js       |  3 +++
 lib/model.js                                  | 11 +++++-----
 lib/options/VirtualOptions.js                 | 12 ++++++++++
 test/model.populate.test.js                   | 22 ++++++++++++++++++-
 4 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index a60c0d558b6..a61a20bb7b3 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -106,6 +106,9 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       if (virtual.options.skip != null && !options.hasOwnProperty('skip')) {
         options.skip = virtual.options.skip;
       }
+      if (virtual.options.limit != null && !options.hasOwnProperty('limit')) {
+        options.limit = virtual.options.limit;
+      }
     } else {
       localField = options.path;
     }
diff --git a/lib/model.js b/lib/model.js
index 6a567e3b1f1..4acd5e0910d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4350,7 +4350,6 @@ function populate(model, docs, options, callback) {
 
     if (mod.options.options && mod.options.options.limit) {
       assignmentOpts.originalLimit = mod.options.options.limit;
-      mod.options.options.limit = mod.options.options.limit * ids.length;
     }
 
     params.push([mod, match, select, assignmentOpts, _next]);
@@ -4392,11 +4391,15 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
   const subPopulate = utils.clone(mod.options.populate);
 
   const queryOptions = Object.assign({
-    skip: mod.options.skip
+    skip: mod.options.skip,
+    limit: mod.options.limit
   }, mod.options.options);
   if (mod.count) {
     delete queryOptions.skip;
   }
+  if (queryOptions.limit != null) {
+    queryOptions.limit = queryOptions.limit * mod.ids.length;
+  }
 
   const query = mod.model.find(match, select, queryOptions);
   // If we're doing virtual populate and projection is inclusive and foreign
@@ -4424,10 +4427,6 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
   }
 
   query.exec(callback);
-
-  if (mod.options.options && mod.options.options.limit) {
-    mod.options.options.limit = assignmentOpts.originalLimit;
-  }
 }
 
 /*!
diff --git a/lib/options/VirtualOptions.js b/lib/options/VirtualOptions.js
index 917a9b94dc7..6bce9b08906 100644
--- a/lib/options/VirtualOptions.js
+++ b/lib/options/VirtualOptions.js
@@ -133,4 +133,16 @@ Object.defineProperty(VirtualOptions.prototype, 'options', opts);
 
 Object.defineProperty(VirtualOptions.prototype, 'skip', opts);
 
+/**
+ * If true, add a `limit` to the query used to `populate()`.
+ *
+ * @api public
+ * @property limit
+ * @memberOf VirtualOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'limit', opts);
+
 module.exports = VirtualOptions;
\ No newline at end of file
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index b5eb2e1a9d3..4cb71d05ef2 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9038,7 +9038,8 @@ describe('model: populate:', function() {
       foreignField: 'parentId',
       justOne: false,
       skip: 1,
-      options: { limit: 2, sort: { _id: 1 } }
+      limit: 2,
+      options: { sort: { _id: 1 } }
     });
 
     const Child = db.model('Child', childSchema);
@@ -9065,6 +9066,25 @@ describe('model: populate:', function() {
         options: { skip: 1 }
       });
       assert.deepEqual(doc.children.map(c => c._id), [2, 3]);
+
+      doc = yield Parent.findOne().populate({ path: 'children', skip: 0 });
+      assert.deepEqual(doc.children.map(c => c._id), [1, 2]);
+
+      doc = yield Parent.findOne().populate({ path: 'children', skip: 0, limit: 1 });
+      assert.deepEqual(doc.children.map(c => c._id), [1]);
+
+      const p2 = yield Parent.create({ name: 'test2' });
+      yield Child.create([
+        { _id: 4, parentId: p2._id },
+        { _id: 5, parentId: p2._id }
+      ]);
+
+      const docs = yield Parent.find().sort({ _id: 1 }).
+        populate({ path: 'children', skip: 0, limit: 2 });
+      assert.equal(docs[0]._id.toString(), p._id.toString());
+      assert.equal(docs[1]._id.toString(), p2._id.toString());
+      assert.deepEqual(docs[0].children.map(c => c._id), [1, 2, 3]);
+      assert.deepEqual(docs[1].children.map(c => c._id), [4]);
     });
   });
 

From 9e0cfde56ba71064c010c9441d82fd848e9875cb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 1 Feb 2020 16:20:43 -0500
Subject: [PATCH 0457/2348] test: reuse collections where possible in
 model.querying.test.js re: #8481

---
 test/model.querying.test.js | 147 +++++++++++-------------------------
 1 file changed, 43 insertions(+), 104 deletions(-)

diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 7c996183098..9a082810af8 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -26,7 +26,24 @@ describe('model: querying:', function() {
   let geoSchema;
   let db;
 
-  before(function() {
+  before(() => { db = start(); });
+
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => {
+    const arr = [];
+
+    if (db.models == null) {
+      return;
+    }
+    for (const model of Object.keys(db.models)) {
+      arr.push(db.models[model].deleteMany({}));
+    }
+
+    return Promise.all(arr);
+  });
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -55,14 +72,11 @@ describe('model: querying:', function() {
       def: {type: String, default: 'kandinsky'}
     });
 
-    mongoose.model('BlogPostB', BlogPostB);
+    BlogPostB = db.model('BlogPost', BlogPostB);
 
-    ModSchema = new Schema({
-      num: Number,
-      str: String
+    ModSchema = Schema({
+      num: Number, str: String
     });
-    mongoose.model('Mod', ModSchema);
-    db = start();
 
     geoSchema = new Schema({loc: {type: [Number], index: '2d'}});
   });
@@ -91,8 +105,6 @@ describe('model: querying:', function() {
   });
 
   it('find returns a Query', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
-
     // query
     assert.ok(BlogPostB.find({}) instanceof Query);
 
@@ -112,8 +124,6 @@ describe('model: querying:', function() {
   });
 
   it('findOne returns a Query', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
-
     // query
     assert.ok(BlogPostB.findOne({}) instanceof Query);
 
@@ -133,8 +143,6 @@ describe('model: querying:', function() {
   });
 
   it('an empty find does not hang', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
-
     function fn() {
       done();
     }
@@ -143,7 +151,6 @@ describe('model: querying:', function() {
   });
 
   it('a query is executed when a callback is passed', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
     let count = 5;
     const q = {_id: new DocumentObjectId}; // make sure the query is fast
 
@@ -171,7 +178,6 @@ describe('model: querying:', function() {
   });
 
   it('query is executed where a callback for findOne', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
     let count = 5;
     const q = {_id: new DocumentObjectId}; // make sure the query is fast
 
@@ -200,13 +206,11 @@ describe('model: querying:', function() {
 
   describe.skip('count', function() {
     it('returns a Query', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       assert.ok(BlogPostB.count({}) instanceof Query);
       done();
     });
 
     it('Query executes when you pass a callback', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       let pending = 2;
 
       function fn() {
@@ -221,7 +225,6 @@ describe('model: querying:', function() {
     });
 
     it('counts documents', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Wooooot ' + random();
 
       const post = new BlogPostB();
@@ -251,15 +254,13 @@ describe('model: querying:', function() {
 
   describe('distinct', function() {
     it('returns a Query', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       assert.ok(BlogPostB.distinct('title', {}) instanceof Query);
       done();
     });
 
     it('executes when you pass a callback', function(done) {
       let Address = new Schema({zip: String});
-      Address = db.model('Address', Address, 'addresses_' + random());
+      Address = db.model('Test', Address);
 
       Address.create({zip: '10010'}, {zip: '10010'}, {zip: '99701'}, function(err) {
         assert.strictEqual(null, err);
@@ -276,7 +277,7 @@ describe('model: querying:', function() {
 
     it('permits excluding conditions gh-1541', function(done) {
       let Address = new Schema({zip: String});
-      Address = db.model('Address', Address, 'addresses_' + random());
+      Address = db.model('Test', Address);
       Address.create({zip: '10010'}, {zip: '10010'}, {zip: '99701'}, function(err) {
         assert.ifError(err);
         Address.distinct('zip', function(err, results) {
@@ -292,15 +293,12 @@ describe('model: querying:', function() {
 
   describe('update', function() {
     it('returns a Query', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       assert.ok(BlogPostB.update({}, {}) instanceof Query);
       assert.ok(BlogPostB.update({}, {}, {}) instanceof Query);
       done();
     });
 
     it('Query executes when you pass a callback', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       let count = 2;
 
       function fn() {
@@ -315,7 +313,7 @@ describe('model: querying:', function() {
     });
 
     it('can handle minimize option (gh-3381)', function() {
-      const Model = db.model('gh3381', {
+      const Model = db.model('Test', {
         name: String,
         mixed: Schema.Types.Mixed
       });
@@ -334,7 +332,6 @@ describe('model: querying:', function() {
 
   describe('findOne', function() {
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Wooooot ' + random();
 
       const post = new BlogPostB();
@@ -354,7 +351,6 @@ describe('model: querying:', function() {
     });
 
     it('casts $modifiers', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const post = new BlogPostB({
         meta: {
           visitors: -10
@@ -377,8 +373,6 @@ describe('model: querying:', function() {
     });
 
     it('querying if an array contains one of multiple members $in a set', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       const post = new BlogPostB();
 
       post.tags.push('football');
@@ -400,8 +394,7 @@ describe('model: querying:', function() {
     });
 
     it('querying if an array contains one of multiple members $in a set 2', function(done) {
-      const BlogPostA = db.model('BlogPostB', collection);
-
+      const BlogPostA = BlogPostB;
       const post = new BlogPostA({tags: ['gooberOne']});
 
       post.save(function(err) {
@@ -438,8 +431,6 @@ describe('model: querying:', function() {
     });
 
     it('querying via $where a string', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({title: 'Steve Jobs', author: 'Steve Jobs'}, function(err, created) {
         assert.ifError(err);
 
@@ -453,8 +444,6 @@ describe('model: querying:', function() {
     });
 
     it('querying via $where a function', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({author: 'Atari', slug: 'Atari'}, function(err, created) {
         assert.ifError(err);
 
@@ -472,7 +461,6 @@ describe('model: querying:', function() {
     });
 
     it('based on nested fields', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const post = new BlogPostB({
         meta: {
           visitors: 5678
@@ -493,8 +481,6 @@ describe('model: querying:', function() {
     });
 
     it('based on embedded doc fields (gh-242, gh-463)', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({comments: [{title: 'i should be queryable'}], numbers: [1, 2, 33333], tags: ['yes', 'no']}, function(err, created) {
         assert.ifError(err);
         BlogPostB.findOne({'comments.title': 'i should be queryable'}, function(err, found) {
@@ -522,8 +508,6 @@ describe('model: querying:', function() {
     });
 
     it('works with nested docs and string ids (gh-389)', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({comments: [{title: 'i should be queryable by _id'}, {title: 'me too me too!'}]}, function(err, created) {
         assert.ifError(err);
         const id = created.comments[1]._id.toString();
@@ -537,8 +521,7 @@ describe('model: querying:', function() {
     });
 
     it('using #all with nested #elemMatch', function(done) {
-      const P = db.model('BlogPostB', collection + '_nestedElemMatch');
-
+      const P = BlogPostB;
       const post = new P({title: 'nested elemMatch'});
       post.comments.push({title: 'comment A'}, {title: 'comment B'}, {title: 'comment C'});
 
@@ -560,8 +543,7 @@ describe('model: querying:', function() {
     });
 
     it('using #or with nested #elemMatch', function(done) {
-      const P = db.model('BlogPostB', collection);
-
+      const P = BlogPostB;
       const post = new P({title: 'nested elemMatch'});
       post.comments.push({title: 'comment D'}, {title: 'comment E'}, {title: 'comment F'});
 
@@ -582,8 +564,6 @@ describe('model: querying:', function() {
     });
 
     it('buffer $in array', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({
         sigs: [Buffer.from([1, 2, 3]),
           Buffer.from([4, 5, 6]),
@@ -604,8 +584,7 @@ describe('model: querying:', function() {
     });
 
     it('regex with Array (gh-599)', function(done) {
-      const B = db.model('BlogPostB', random());
-
+      const B = BlogPostB;
       B.create({tags: 'wooof baaaark meeeeow'.split(' ')}, function(err) {
         assert.ifError(err);
         B.findOne({tags: /ooof$/}, function(err, doc) {
@@ -624,8 +603,7 @@ describe('model: querying:', function() {
     });
 
     it('regex with options', function(done) {
-      const B = db.model('BlogPostB', collection);
-
+      const B = BlogPostB;
       const post = new B({title: '$option queries'});
       post.save(function(err) {
         assert.ifError(err);
@@ -638,7 +616,6 @@ describe('model: querying:', function() {
     });
 
     it('works with $elemMatch and $in combo (gh-1100)', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const id1 = new DocumentObjectId;
       const id2 = new DocumentObjectId;
 
@@ -656,7 +633,6 @@ describe('model: querying:', function() {
 
   describe('findById', function() {
     it('handles undefined', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Edwald ' + random();
 
       const post = new BlogPostB();
@@ -674,7 +650,6 @@ describe('model: querying:', function() {
     });
 
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Edwald ' + random();
 
       const post = new BlogPostB();
@@ -708,7 +683,6 @@ describe('model: querying:', function() {
     });
 
     it('works with partial initialization', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       let queries = 5;
 
       const post = new BlogPostB();
@@ -795,8 +769,6 @@ describe('model: querying:', function() {
     });
 
     it('querying if an array contains at least a certain single member (gh-220)', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       const post = new BlogPostB();
 
       post.tags.push('cat');
@@ -814,8 +786,6 @@ describe('model: querying:', function() {
 
 
     it('where an array where the $slice operator', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({numbers: [500, 600, 700, 800]}, function(err, created) {
         assert.ifError(err);
         BlogPostB.findById(created._id, {numbers: {$slice: 2}}, function(err, found) {
@@ -846,7 +816,6 @@ describe('model: querying:', function() {
 
   describe('find', function() {
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Wooooot ' + random();
 
       const post = new BlogPostB();
@@ -878,7 +847,6 @@ describe('model: querying:', function() {
     });
 
     it('returns docs where an array that contains one specific member', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       BlogPostB.create({numbers: [100, 101, 102]}, function(err, created) {
         assert.ifError(err);
         BlogPostB.find({numbers: 100}, function(err, found) {
@@ -932,7 +900,6 @@ describe('model: querying:', function() {
     });
 
     it('with partial initialization', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       let queries = 4;
 
       const post = new BlogPostB();
@@ -995,8 +962,7 @@ describe('model: querying:', function() {
 
     it('where $exists', function() {
       const ExistsSchema = new Schema({ a: Number, b: String });
-      mongoose.model('Exists', ExistsSchema);
-      const Exists = db.model('Exists');
+      const Exists = db.model('Test', ExistsSchema);
 
       return co(function*() {
         yield Exists.create({ a: 1 }, { b: 'hi' });
@@ -1022,7 +988,6 @@ describe('model: querying:', function() {
     });
 
     it('works with $elemMatch (gh-1100)', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const id1 = new DocumentObjectId;
       const id2 = new DocumentObjectId;
 
@@ -1037,7 +1002,7 @@ describe('model: querying:', function() {
     });
 
     it('where $mod', function(done) {
-      const Mod = db.model('Mod', 'mods_' + random());
+      const Mod = db.model('Test', ModSchema);
       Mod.create({num: 1}, function(err, one) {
         assert.ifError(err);
         Mod.create({num: 2}, function(err) {
@@ -1053,7 +1018,7 @@ describe('model: querying:', function() {
     });
 
     it('where $not', function(done) {
-      const Mod = db.model('Mod', 'mods_' + random());
+      const Mod = db.model('Test', ModSchema);
       Mod.create({num: 1}, function(err) {
         assert.ifError(err);
         Mod.create({num: 2}, function(err, two) {
@@ -1069,7 +1034,7 @@ describe('model: querying:', function() {
     });
 
     it('where or()', function(done) {
-      const Mod = db.model('Mod', 'mods_' + random());
+      const Mod = db.model('Test', ModSchema);
 
       Mod.create({num: 1}, {num: 2, str: 'two'}, function(err, one, two) {
         assert.ifError(err);
@@ -1142,7 +1107,7 @@ describe('model: querying:', function() {
     });
 
     it('using $or with array of Document', function(done) {
-      const Mod = db.model('Mod', 'mods_' + random());
+      const Mod = db.model('Test', ModSchema);
 
       Mod.create({num: 1}, function(err, one) {
         assert.ifError(err);
@@ -1159,7 +1124,7 @@ describe('model: querying:', function() {
     });
 
     it('where $ne', function(done) {
-      const Mod = db.model('Mod', 'mods_' + random());
+      const Mod = db.model('Test', ModSchema);
       Mod.create({num: 1}, function(err) {
         assert.ifError(err);
         Mod.create({num: 2}, function(err, two) {
@@ -1180,7 +1145,7 @@ describe('model: querying:', function() {
     });
 
     it('where $nor', function(done) {
-      const Mod = db.model('Mod', 'nor_' + random());
+      const Mod = db.model('Test', ModSchema);
 
       Mod.create({num: 1}, {num: 2, str: 'two'}, function(err, one, two) {
         assert.ifError(err);
@@ -1227,8 +1192,6 @@ describe('model: querying:', function() {
     });
 
     it('STRICT null matches', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection + random());
-
       const a = {title: 'A', author: null};
       const b = {title: 'B'};
       BlogPostB.create(a, b, function(err, createdA) {
@@ -1243,8 +1206,6 @@ describe('model: querying:', function() {
     });
 
     it('null matches null and undefined', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection + random());
-
       BlogPostB.create(
         {title: 'A', author: null},
         {title: 'B'}, function(err) {
@@ -1258,8 +1219,6 @@ describe('model: querying:', function() {
     });
 
     it('a document whose arrays contain at least $all string values', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       const post = new BlogPostB({title: 'Aristocats'});
 
       post.tags.push('onex');
@@ -1302,13 +1261,13 @@ describe('model: querying:', function() {
     });
 
     it('using #nor with nested #elemMatch', function(done) {
-      const P = db.model('BlogPostB', collection + '_norWithNestedElemMatch');
-
       const p0 = {title: 'nested $nor elemMatch1', comments: []};
 
       const p1 = {title: 'nested $nor elemMatch0', comments: []};
       p1.comments.push({title: 'comment X'}, {title: 'comment Y'}, {title: 'comment W'});
 
+      const P = BlogPostB;
+
       P.create(p0, p1, function(err, post0, post1) {
         assert.ifError(err);
 
@@ -1327,8 +1286,6 @@ describe('model: querying:', function() {
     });
 
     it('strings via regexp', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({title: 'Next to Normal'}, function(err, created) {
         assert.ifError(err);
         BlogPostB.findOne({title: /^Next/}, function(err, found) {
@@ -1363,7 +1320,6 @@ describe('model: querying:', function() {
     });
 
     it('a document whose arrays contain at least $all values', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const a1 = {numbers: [-1, -2, -3, -4], meta: {visitors: 4}};
       const a2 = {numbers: [0, -1, -2, -3, -4]};
       BlogPostB.create(a1, a2, function(err, whereoutZero, whereZero) {
@@ -1388,8 +1344,6 @@ describe('model: querying:', function() {
     });
 
     it('where $size', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({numbers: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]}, function(err) {
         assert.ifError(err);
         BlogPostB.create({numbers: [11, 12, 13, 14, 15, 16, 17, 18, 19, 20]}, function(err) {
@@ -1411,7 +1365,7 @@ describe('model: querying:', function() {
     });
 
     it('$gt, $lt, $lte, $gte work on strings', function(done) {
-      const D = db.model('D', new Schema({dt: String}), collection);
+      const D = db.model('Test', new Schema({dt: String}));
 
       D.create({dt: '2011-03-30'}, cb);
       D.create({dt: '2011-03-31'}, cb);
@@ -1467,7 +1421,7 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const blogPost = db.model('BlogPostB', collection);
+        const blogPost = BlogPostB;
 
         blogPost.collection.createIndex({title: 'text'}, function(error) {
           assert.ifError(error);
@@ -1508,7 +1462,7 @@ describe('model: querying:', function() {
           tag: String
         });
 
-        const Example = db.model('gh3824', exampleSchema);
+        const Example = db.model('Test', exampleSchema);
 
         return co(function*() {
           yield Example.init(); // Wait for index build
@@ -1539,8 +1493,6 @@ describe('model: querying:', function() {
 
   describe('limit', function() {
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({title: 'first limit'}, function(err, first) {
         assert.ifError(err);
         BlogPostB.create({title: 'second limit'}, function(err, second) {
@@ -1562,8 +1514,6 @@ describe('model: querying:', function() {
 
   describe('skip', function() {
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({title: '1 skip'}, function(err) {
         assert.ifError(err);
         BlogPostB.create({title: '2 skip'}, function(err, second) {
@@ -1585,8 +1535,6 @@ describe('model: querying:', function() {
 
   describe('sort', function() {
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.create({meta: {visitors: 100}}, function(err, least) {
         assert.ifError(err);
         BlogPostB.create({meta: {visitors: 300}}, function(err, largest) {
@@ -1613,7 +1561,7 @@ describe('model: querying:', function() {
         return done();
       }
 
-      const blogPost = db.model('BlogPostB', collection);
+      const blogPost = BlogPostB;
 
       blogPost.collection.createIndex({title: 'text'}, function(error) {
         assert.ifError(error);
@@ -1642,8 +1590,6 @@ describe('model: querying:', function() {
 
   describe('nested mixed "x.y.z"', function() {
     it('works', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
-
       BlogPostB.find({'mixed.nested.stuff': 'skynet'}, function(err) {
         assert.ifError(err);
         done();
@@ -1799,8 +1745,7 @@ describe('model: querying:', function() {
 
   describe('and', function() {
     it('works with queries gh-1188', function(done) {
-      const B = db.model('BlogPostB');
-
+      const B = BlogPostB;
       B.create({title: 'and operator', published: false, author: 'Me'}, function(err) {
         assert.ifError(err);
 
@@ -1996,7 +1941,6 @@ describe('model: querying:', function() {
   });
 
   it('with previously existing null values in the db', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
     const post = new BlogPostB();
 
     post.collection.insertOne({meta: {visitors: 9898, a: null}}, {}, function(err, b) {
@@ -2011,7 +1955,6 @@ describe('model: querying:', function() {
   });
 
   it('with unused values in the db', function(done) {
-    const BlogPostB = db.model('BlogPostB', collection);
     const post = new BlogPostB();
 
     post.collection.insertOne({meta: {visitors: 9898, color: 'blue'}}, {}, function(err, b) {
@@ -2508,7 +2451,6 @@ describe('model: querying:', function() {
 
   describe('lean', function() {
     it('find', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Wooooot ' + random();
 
       const post = new BlogPostB();
@@ -2531,7 +2473,6 @@ describe('model: querying:', function() {
     });
 
     it('findOne', function(done) {
-      const BlogPostB = db.model('BlogPostB', collection);
       const title = 'Wooooot ' + random();
 
       const post = new BlogPostB();
@@ -2648,8 +2589,6 @@ describe('model: querying:', function() {
       });
 
       it('casts $eq (gh-2752)', function(done) {
-        const BlogPostB = db.model('BlogPostB', collection);
-
         BlogPostB.findOne(
           {_id: {$eq: '000000000000000000000001'}, numbers: {$eq: [1, 2]}},
           function(err, doc) {

From 5242e41effa06f67aea00c476457180b8c0a6863 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 2 Feb 2020 19:49:35 -0500
Subject: [PATCH 0458/2348] docs(queries): remove dead link

---
 docs/queries.pug | 1 -
 1 file changed, 1 deletion(-)

diff --git a/docs/queries.pug b/docs/queries.pug
index 0917b5200d8..faa4d68184c 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -48,7 +48,6 @@ block content
     <ul class="toc">
       <li><a href="#executing">Executing</a></li>
       <li><a href="#queries-are-not-promises">Queries are Not Promises</a></li>
-      <li><a href="#connection-string-options">Connection String Options</a></li>
       <li><a href="#refs">References to other documents</a></li>
       <li><a href="#streaming">Streaming</a></li>
       <li><a href="#versus-aggregation">Versus Aggregation</a></li>

From c7e4f2019cc94191c729a5e89d31ead50563bc9f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 3 Feb 2020 23:23:35 +0200
Subject: [PATCH 0459/2348] Add preoperty for SchemaType.set(...)

---
 lib/schema/array.js      | 23 +++++++++++++++++++++++
 lib/schematype.js        |  3 +++
 test/schema.type.test.js | 23 +++++++++++------------
 3 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index e32cff9bfc5..0bb78ad5963 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -121,6 +121,7 @@ function SchemaArray(key, cast, options, schemaOptions) {
  */
 SchemaArray.schemaName = 'Array';
 
+
 /**
  * Options for all arrays.
  *
@@ -132,6 +133,28 @@ SchemaArray.schemaName = 'Array';
 
 SchemaArray.options = { castNonArrays: true };
 
+SchemaArray.defaultOptions = {};
+
+/**
+ * Sets a default option for all Array instances.
+ *
+ * ####Example:
+ *
+ *     // Make all Array instances have `required` of true by default.
+ *     mongoose.Schema.Array.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Array }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+SchemaArray.set = SchemaType.set;
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schematype.js b/lib/schematype.js
index 47b3527fe33..3488e43e22d 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -151,6 +151,9 @@ SchemaType.cast = function cast(caster) {
 };
 
 SchemaType.set = function set(option, value) {
+  if (!this.hasOwnProperty('defaultOptions')) {
+    this.defaultOptions = Object.assign({}, this.defaultOptions);
+  }
   this.defaultOptions[option] = value;
 };
 
diff --git a/test/schema.type.test.js b/test/schema.type.test.js
index 71c7c07e6a7..9c6f1a02ab7 100644
--- a/test/schema.type.test.js
+++ b/test/schema.type.test.js
@@ -108,23 +108,22 @@ describe('schematype', function() {
       });
     });
 
-    const mongooseInstance = new mongoose.Mongoose();
-
     [
-      mongooseInstance.SchemaTypes.String,
-      mongooseInstance.SchemaTypes.Number,
-      mongooseInstance.SchemaTypes.Boolean,
-      mongooseInstance.SchemaTypes.Buffer,
-      mongooseInstance.SchemaTypes.Date,
-      mongooseInstance.SchemaTypes.ObjectId,
-      mongooseInstance.SchemaTypes.Mixed,
-      mongooseInstance.SchemaTypes.Decimal128,
-      mongooseInstance.SchemaTypes.Map
+      mongoose.SchemaTypes.String,
+      mongoose.SchemaTypes.Number,
+      mongoose.SchemaTypes.Boolean,
+      mongoose.SchemaTypes.Array,
+      mongoose.SchemaTypes.Buffer,
+      mongoose.SchemaTypes.Date,
+      mongoose.SchemaTypes.ObjectId,
+      mongoose.SchemaTypes.Mixed,
+      mongoose.SchemaTypes.Decimal128,
+      mongoose.SchemaTypes.Map
     ].forEach((type) => {
       it(type.name + ', when given a default option, set its', () => {
         // Act
         type.set('someRandomOption', true);
-        const schema = new mongooseInstance.Schema({test: type});
+        const schema = new mongoose.Schema({test: type});
 
         // Assert
         assert.equal(schema.path('test').options.someRandomOption, true);

From dc8ea7ab9c6929877595c9bc82489cdcb235430f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 10 Jan 2020 04:37:50 +0200
Subject: [PATCH 0460/2348] Add support for default options per type

---
 lib/schema/string.js      | 12 ++++++++++++
 test/types.string.test.js | 29 +++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 test/types.string.test.js

diff --git a/lib/schema/string.js b/lib/schema/string.js
index 849e4e6083d..4fb70826919 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -25,6 +25,12 @@ let Document;
  */
 
 function SchemaString(key, options) {
+  const defaultOptionsKeys = Object.keys(SchemaString.defaultOptions);
+  for (const optionName of defaultOptionsKeys) {
+    if (SchemaString.defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
+      options[optionName] = SchemaString.defaultOptions[optionName];
+    }
+  }
   this.enumValues = [];
   this.regExp = null;
   SchemaType.call(this, key, options, 'String');
@@ -38,6 +44,12 @@ function SchemaString(key, options) {
  */
 SchemaString.schemaName = 'String';
 
+SchemaString.defaultOptions = {};
+
+SchemaString.setDefaultOption = function setDefaultOption(optionName,value) {
+  SchemaString.defaultOptions[optionName] = value;
+};
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/test/types.string.test.js b/test/types.string.test.js
new file mode 100644
index 00000000000..390fd184b0b
--- /dev/null
+++ b/test/types.string.test.js
@@ -0,0 +1,29 @@
+'use strict';
+
+/**
+ * Module dependencies.
+ */
+
+const mongoose = require('./common').mongoose;
+
+const assert = require('assert');
+
+/**
+ * Test.
+ */
+
+describe('types.string', function() {
+  describe('Schema.Types.String.setDefaultOptions(...)', function() {
+    it('when given an option, sets it', () => {
+      // Arrange
+      const mongooseInstance = new mongoose.Mongoose();
+
+      // Act
+      mongooseInstance.Schema.Types.String.setDefaultOption('trim',true);
+      const userSchema = new mongooseInstance.Schema({name:{type:String}});
+
+      // Assert
+      assert.equal(userSchema.path('name').options.trim, true);
+    });
+  });
+});

From 9cc1ae8c7fec35d36ed1b4540986fb5388588706 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 10 Jan 2020 06:06:17 +0200
Subject: [PATCH 0461/2348] [WIP] Fixes #8487

---
 lib/helpers/schematype/getDefaultOptionSetter.js |  8 ++++++++
 lib/schema/array.js                              |  4 ++++
 lib/schema/boolean.js                            |  4 ++++
 lib/schema/buffer.js                             |  4 ++++
 lib/schema/date.js                               |  4 ++++
 lib/schema/decimal128.js                         |  4 ++++
 lib/schema/map.js                                |  5 ++++-
 lib/schema/mixed.js                              |  4 ++++
 lib/schema/number.js                             |  4 ++++
 lib/schema/objectid.js                           |  4 ++++
 lib/schema/string.js                             | 12 ++----------
 lib/schematype.js                                | 10 ++++++++++
 12 files changed, 56 insertions(+), 11 deletions(-)
 create mode 100644 lib/helpers/schematype/getDefaultOptionSetter.js

diff --git a/lib/helpers/schematype/getDefaultOptionSetter.js b/lib/helpers/schematype/getDefaultOptionSetter.js
new file mode 100644
index 00000000000..9266c240a62
--- /dev/null
+++ b/lib/helpers/schematype/getDefaultOptionSetter.js
@@ -0,0 +1,8 @@
+'use strict';
+function getDefaultOptionSetter(type) {
+  return function setDefaultOption(optionName, value) {
+    type.defaultOptions[optionName] = value;
+  };
+}
+
+module.exports = getDefaultOptionSetter;
\ No newline at end of file
diff --git a/lib/schema/array.js b/lib/schema/array.js
index e32cff9bfc5..74d2d829fa1 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -18,6 +18,7 @@ const utils = require('../utils');
 const castToNumber = require('./operators/helpers').castToNumber;
 const geospatial = require('./operators/geospatial');
 const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminatorByValue');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let MongooseArray;
 let EmbeddedDoc;
@@ -121,6 +122,9 @@ function SchemaArray(key, cast, options, schemaOptions) {
  */
 SchemaArray.schemaName = 'Array';
 
+SchemaArray.defaultOptions = {};
+SchemaArray.setDefaultOption = getDefaultOptionSetter(SchemaArray);
+
 /**
  * Options for all arrays.
  *
diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 13d796c45f8..86804dbd8c5 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -8,6 +8,7 @@ const CastError = require('../error/cast');
 const SchemaType = require('../schematype');
 const castBoolean = require('../cast/boolean');
 const utils = require('../utils');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Boolean SchemaType constructor.
@@ -30,6 +31,9 @@ function SchemaBoolean(path, options) {
  */
 SchemaBoolean.schemaName = 'Boolean';
 
+SchemaBoolean.defaultOptions = {};
+SchemaBoolean.setDefaultOption = getDefaultOptionSetter(SchemaBoolean);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 91edf2aaf71..b75328add28 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -11,6 +11,7 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const Binary = MongooseBuffer.Binary;
 const CastError = SchemaType.CastError;
@@ -37,6 +38,9 @@ function SchemaBuffer(key, options) {
  */
 SchemaBuffer.schemaName = 'Buffer';
 
+SchemaBuffer.defaultOptions = {};
+SchemaBuffer.setDefaultOption = getDefaultOptionSetter(SchemaBuffer);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/date.js b/lib/schema/date.js
index b2a65d12cde..9b7d1c002ee 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -9,6 +9,7 @@ const SchemaDateOptions = require('../options/SchemaDateOptions');
 const SchemaType = require('../schematype');
 const castDate = require('../cast/date');
 const utils = require('../utils');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 
@@ -33,6 +34,9 @@ function SchemaDate(key, options) {
  */
 SchemaDate.schemaName = 'Date';
 
+SchemaDate.defaultOptions = {};
+SchemaDate.setDefaultOption = getDefaultOptionSetter(SchemaDate);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index 0978d47b267..0520d2c0cc2 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -11,6 +11,7 @@ const castDecimal128 = require('../cast/decimal128');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let Document;
 
@@ -35,6 +36,9 @@ function Decimal128(key, options) {
  */
 Decimal128.schemaName = 'Decimal128';
 
+Decimal128.defaultOptions = {};
+Decimal128.setDefaultOption = getDefaultOptionSetter(Decimal128);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/map.js b/lib/schema/map.js
index 14fd248e832..ee3b946a397 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -7,7 +7,7 @@
 const MongooseMap = require('../types/map');
 const SchemaMapOptions = require('../options/SchemaMapOptions');
 const SchemaType = require('../schematype');
-
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 /*!
  * ignore
  */
@@ -17,6 +17,9 @@ class Map extends SchemaType {
     super(key, options, 'Map');
     this.$isSchemaMap = true;
   }
+  static setDefaultOption() {
+    return getDefaultOptionSetter(Map);
+  }
 
   cast(val, doc, init) {
     if (val instanceof MongooseMap) {
diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 672cc519167..36316f37a97 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -7,6 +7,7 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const utils = require('../utils');
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Mixed SchemaType constructor.
@@ -44,6 +45,9 @@ function Mixed(path, options) {
  */
 Mixed.schemaName = 'Mixed';
 
+Mixed.defaultOptions = {};
+Mixed.setDefaultOption = getDefaultOptionSetter(Mixed);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/number.js b/lib/schema/number.js
index e32ae2b4237..47158c9d16d 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -12,6 +12,7 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -102,6 +103,9 @@ SchemaNumber.cast = function cast(caster) {
  */
 SchemaNumber.schemaName = 'Number';
 
+SchemaNumber.defaultOptions = {};
+SchemaNumber.setDefaultOption = getDefaultOptionSetter(SchemaNumber);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index 761ebd1df4a..bba8e62873b 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -11,6 +11,7 @@ const oid = require('../types/objectid');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -45,6 +46,9 @@ function ObjectId(key, options) {
  */
 ObjectId.schemaName = 'ObjectId';
 
+ObjectId.defaultOptions = {};
+ObjectId.setDefaultOption = getDefaultOptionSetter(ObjectId);
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 4fb70826919..17a5ce8c715 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -11,6 +11,7 @@ const castString = require('../cast/string');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -25,12 +26,6 @@ let Document;
  */
 
 function SchemaString(key, options) {
-  const defaultOptionsKeys = Object.keys(SchemaString.defaultOptions);
-  for (const optionName of defaultOptionsKeys) {
-    if (SchemaString.defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
-      options[optionName] = SchemaString.defaultOptions[optionName];
-    }
-  }
   this.enumValues = [];
   this.regExp = null;
   SchemaType.call(this, key, options, 'String');
@@ -45,10 +40,7 @@ function SchemaString(key, options) {
 SchemaString.schemaName = 'String';
 
 SchemaString.defaultOptions = {};
-
-SchemaString.setDefaultOption = function setDefaultOption(optionName,value) {
-  SchemaString.defaultOptions[optionName] = value;
-};
+SchemaString.setDefaultOption = getDefaultOptionSetter(SchemaString);
 
 /*!
  * Inherits from SchemaType.
diff --git a/lib/schematype.js b/lib/schematype.js
index 35c028fe9fc..f813c31f61e 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -44,6 +44,16 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
+  const defaultOptions = this.constructor.defaultOptions;
+  const defaultOptionsKeys = Object.keys(defaultOptions);
+
+  for (const optionName of defaultOptionsKeys) {
+    if (defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
+      options[optionName] = defaultOptions[optionName];
+    }
+  }
+
+
   const Options = this.OptionsConstructor || SchemaTypeOptions;
   this.options = new Options(options);
   this._index = null;

From 56903858d873434fe9348e04fb28d302ae0cc3d4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 10 Jan 2020 06:09:35 +0200
Subject: [PATCH 0462/2348] Add fallback to empty object for default options

---
 lib/schematype.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index f813c31f61e..9ff32198d74 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -44,7 +44,7 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
-  const defaultOptions = this.constructor.defaultOptions;
+  const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
 
   for (const optionName of defaultOptionsKeys) {

From 2dc70d0e407c5200aff254a78714bded7ebee201 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:32:33 +0200
Subject: [PATCH 0463/2348] Fixes #8487 Add set to SchemaType and inheerit

---
 .../schematype/getDefaultOptionSetter.js      |  8 -----
 lib/schema/array.js                           | 23 ++++++++++++--
 lib/schema/boolean.js                         | 23 ++++++++++++--
 lib/schema/buffer.js                          | 23 ++++++++++++--
 lib/schema/date.js                            | 23 ++++++++++++--
 lib/schema/decimal128.js                      | 23 ++++++++++++--
 lib/schema/map.js                             |  8 +++--
 lib/schema/mixed.js                           | 23 ++++++++++++--
 lib/schema/number.js                          | 23 ++++++++++++--
 lib/schema/objectid.js                        | 23 ++++++++++++--
 lib/schema/string.js                          | 23 ++++++++++++--
 lib/schematype.js                             | 10 +++++--
 test.js                                       | 13 ++++++++
 test/schematype.test.js                       | 30 +++++++++++++++++++
 test/types.string.test.js                     | 29 ------------------
 15 files changed, 244 insertions(+), 61 deletions(-)
 delete mode 100644 lib/helpers/schematype/getDefaultOptionSetter.js
 create mode 100644 test.js
 delete mode 100644 test/types.string.test.js

diff --git a/lib/helpers/schematype/getDefaultOptionSetter.js b/lib/helpers/schematype/getDefaultOptionSetter.js
deleted file mode 100644
index 9266c240a62..00000000000
--- a/lib/helpers/schematype/getDefaultOptionSetter.js
+++ /dev/null
@@ -1,8 +0,0 @@
-'use strict';
-function getDefaultOptionSetter(type) {
-  return function setDefaultOption(optionName, value) {
-    type.defaultOptions[optionName] = value;
-  };
-}
-
-module.exports = getDefaultOptionSetter;
\ No newline at end of file
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 74d2d829fa1..475de969089 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -18,7 +18,6 @@ const utils = require('../utils');
 const castToNumber = require('./operators/helpers').castToNumber;
 const geospatial = require('./operators/geospatial');
 const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminatorByValue');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let MongooseArray;
 let EmbeddedDoc;
@@ -123,7 +122,6 @@ function SchemaArray(key, cast, options, schemaOptions) {
 SchemaArray.schemaName = 'Array';
 
 SchemaArray.defaultOptions = {};
-SchemaArray.setDefaultOption = getDefaultOptionSetter(SchemaArray);
 
 /**
  * Options for all arrays.
@@ -136,6 +134,27 @@ SchemaArray.setDefaultOption = getDefaultOptionSetter(SchemaArray);
 
 SchemaArray.options = { castNonArrays: true };
 
+/**
+ * Sets a default option for all Array instances.
+ *
+ * ####Example:
+ *
+ *     // Make all arrays have option `required` equal to true.
+ *     mongoose.Schema.Array.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Array }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaArray.set = SchemaType.set;
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 86804dbd8c5..4280d941f7e 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -8,7 +8,6 @@ const CastError = require('../error/cast');
 const SchemaType = require('../schematype');
 const castBoolean = require('../cast/boolean');
 const utils = require('../utils');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Boolean SchemaType constructor.
@@ -32,7 +31,6 @@ function SchemaBoolean(path, options) {
 SchemaBoolean.schemaName = 'Boolean';
 
 SchemaBoolean.defaultOptions = {};
-SchemaBoolean.setDefaultOption = getDefaultOptionSetter(SchemaBoolean);
 
 /*!
  * Inherits from SchemaType.
@@ -46,6 +44,27 @@ SchemaBoolean.prototype.constructor = SchemaBoolean;
 
 SchemaBoolean._cast = castBoolean;
 
+/**
+ * Sets a default option for all Boolean instances.
+ *
+ * ####Example:
+ *
+ *     // Make all booleans have `default` of false.
+ *     mongoose.Schema.Boolean.set('default', false);
+ *
+ *     const Order = mongoose.model('Order', new Schema({ isPaid: Boolean }));
+ *     new Order({ }).isPaid; // false
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaBoolean.set = SchemaType.set;
+
 /**
  * Get/set the function used to cast arbitrary values to booleans.
  *
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index b75328add28..81f03009177 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -11,7 +11,6 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const Binary = MongooseBuffer.Binary;
 const CastError = SchemaType.CastError;
@@ -39,7 +38,6 @@ function SchemaBuffer(key, options) {
 SchemaBuffer.schemaName = 'Buffer';
 
 SchemaBuffer.defaultOptions = {};
-SchemaBuffer.setDefaultOption = getDefaultOptionSetter(SchemaBuffer);
 
 /*!
  * Inherits from SchemaType.
@@ -54,6 +52,27 @@ SchemaBuffer.prototype.OptionsConstructor = SchemaBufferOptions;
 
 SchemaBuffer._checkRequired = v => !!(v && v.length);
 
+/**
+ * Sets a default option for all Buffer instances.
+ *
+ * ####Example:
+ *
+ *     // Make all buffers have `required` of true by default.
+ *     mongoose.Schema.Buffer.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Buffer }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaBuffer.set = SchemaType.set;
+
 /**
  * Override the function the required validator uses to check whether a string
  * passes the `required` check.
diff --git a/lib/schema/date.js b/lib/schema/date.js
index 9b7d1c002ee..ebeaf472237 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -9,7 +9,6 @@ const SchemaDateOptions = require('../options/SchemaDateOptions');
 const SchemaType = require('../schematype');
 const castDate = require('../cast/date');
 const utils = require('../utils');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 
@@ -35,7 +34,6 @@ function SchemaDate(key, options) {
 SchemaDate.schemaName = 'Date';
 
 SchemaDate.defaultOptions = {};
-SchemaDate.setDefaultOption = getDefaultOptionSetter(SchemaDate);
 
 /*!
  * Inherits from SchemaType.
@@ -50,6 +48,27 @@ SchemaDate.prototype.OptionsConstructor = SchemaDateOptions;
 
 SchemaDate._cast = castDate;
 
+/**
+ * Sets a default option for all Date instances.
+ *
+ * ####Example:
+ *
+ *     // Make all dates have `required` of true by default.
+ *     mongoose.Schema.Date.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Date }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaDate.set = SchemaType.set;
+
 /**
  * Get/set the function used to cast arbitrary values to dates.
  *
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index 0520d2c0cc2..ca9bcb4737b 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -11,7 +11,6 @@ const castDecimal128 = require('../cast/decimal128');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 let Document;
 
@@ -37,7 +36,6 @@ function Decimal128(key, options) {
 Decimal128.schemaName = 'Decimal128';
 
 Decimal128.defaultOptions = {};
-Decimal128.setDefaultOption = getDefaultOptionSetter(Decimal128);
 
 /*!
  * Inherits from SchemaType.
@@ -51,6 +49,27 @@ Decimal128.prototype.constructor = Decimal128;
 
 Decimal128._cast = castDecimal128;
 
+/**
+ * Sets a default option for all Decimal128 instances.
+ *
+ * ####Example:
+ *
+ *     // Make all decimal 128s have `required` of true by default.
+ *     mongoose.Schema.Decimal128.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: mongoose.Decimal128 }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+Decimal128.set = SchemaType.set;
+
 /**
  * Get/set the function used to cast arbitrary values to decimals.
  *
diff --git a/lib/schema/map.js b/lib/schema/map.js
index ee3b946a397..2db6bfc10b9 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -7,7 +7,6 @@
 const MongooseMap = require('../types/map');
 const SchemaMapOptions = require('../options/SchemaMapOptions');
 const SchemaType = require('../schematype');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 /*!
  * ignore
  */
@@ -17,8 +16,9 @@ class Map extends SchemaType {
     super(key, options, 'Map');
     this.$isSchemaMap = true;
   }
-  static setDefaultOption() {
-    return getDefaultOptionSetter(Map);
+
+  set(option,value) {
+    return SchemaType.set(option,value);
   }
 
   cast(val, doc, init) {
@@ -57,4 +57,6 @@ class Map extends SchemaType {
 
 Map.prototype.OptionsConstructor = SchemaMapOptions;
 
+Map.defaultOptions = {};
+
 module.exports = Map;
diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 36316f37a97..abea3530763 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -7,7 +7,6 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const utils = require('../utils');
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 /**
  * Mixed SchemaType constructor.
@@ -46,7 +45,6 @@ function Mixed(path, options) {
 Mixed.schemaName = 'Mixed';
 
 Mixed.defaultOptions = {};
-Mixed.setDefaultOption = getDefaultOptionSetter(Mixed);
 
 /*!
  * Inherits from SchemaType.
@@ -74,6 +72,27 @@ Mixed.prototype.constructor = Mixed;
 
 Mixed.get = SchemaType.get;
 
+/**
+ * Sets a default option for all Mixed instances.
+ *
+ * ####Example:
+ *
+ *     // Make all mixed instances have `required` of true by default.
+ *     mongoose.Schema.Mixed.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: mongoose.Mixed }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+Mixed.set = SchemaType.set;
+
 /**
  * Casts `val` for Mixed.
  *
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 47158c9d16d..d868b4e581b 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -12,7 +12,6 @@ const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -50,6 +49,27 @@ function SchemaNumber(key, options) {
 
 SchemaNumber.get = SchemaType.get;
 
+/**
+ * Sets a default option for all Number instances.
+ *
+ * ####Example:
+ *
+ *     // Make all numbers have option `min` equal to 0.
+ *     mongoose.Schema.Number.set('min', 0);
+ *
+ *     const Order = mongoose.model('Order', new Schema({ amount: Number }));
+ *     new Order({ amount: -10 }).validateSync().errors.amount.message; // Path `amount` must be larger than 0.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaNumber.set = SchemaType.set;
+
 /*!
  * ignore
  */
@@ -104,7 +124,6 @@ SchemaNumber.cast = function cast(caster) {
 SchemaNumber.schemaName = 'Number';
 
 SchemaNumber.defaultOptions = {};
-SchemaNumber.setDefaultOption = getDefaultOptionSetter(SchemaNumber);
 
 /*!
  * Inherits from SchemaType.
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index bba8e62873b..aa7b4fb53c5 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -11,7 +11,6 @@ const oid = require('../types/objectid');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -47,7 +46,6 @@ function ObjectId(key, options) {
 ObjectId.schemaName = 'ObjectId';
 
 ObjectId.defaultOptions = {};
-ObjectId.setDefaultOption = getDefaultOptionSetter(ObjectId);
 
 /*!
  * Inherits from SchemaType.
@@ -76,6 +74,27 @@ ObjectId.prototype.OptionsConstructor = SchemaObjectIdOptions;
 
 ObjectId.get = SchemaType.get;
 
+/**
+ * Sets a default option for all ObjectId instances.
+ *
+ * ####Example:
+ *
+ *     // Make all object ids have option `required` equal to true.
+ *     mongoose.Schema.ObjectId.set('required', true);
+ *
+ *     const Order = mongoose.model('Order', new Schema({ userId: ObjectId }));
+ *     new Order({ }).validateSync().errors.userId.message; // Path `userId` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+ObjectId.set = SchemaType.set;
+
 /**
  * Adds an auto-generated ObjectId default if turnOn is true.
  * @param {Boolean} turnOn auto generated ObjectId defaults
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 17a5ce8c715..e0771bec065 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -11,7 +11,6 @@ const castString = require('../cast/string');
 const utils = require('../utils');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-const getDefaultOptionSetter = require('../helpers/schematype/getDefaultOptionSetter');
 
 const CastError = SchemaType.CastError;
 let Document;
@@ -40,7 +39,6 @@ function SchemaString(key, options) {
 SchemaString.schemaName = 'String';
 
 SchemaString.defaultOptions = {};
-SchemaString.setDefaultOption = getDefaultOptionSetter(SchemaString);
 
 /*!
  * Inherits from SchemaType.
@@ -120,6 +118,27 @@ SchemaString.cast = function cast(caster) {
 
 SchemaString.get = SchemaType.get;
 
+/**
+ * Sets a default option for all String instances.
+ *
+ * ####Example:
+ *
+ *     // Make all strings have option `trim` equal to true.
+ *     mongoose.Schema.String.set('trim', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ name: String }));
+ *     new User({ name: '   John Doe   ' }).name; // 'John Doe'
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SchemaString.set = SchemaType.set;
+
 /*!
  * ignore
  */
diff --git a/lib/schematype.js b/lib/schematype.js
index 9ff32198d74..718dba327b1 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -47,9 +47,9 @@ function SchemaType(path, options, instance) {
   const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
 
-  for (const optionName of defaultOptionsKeys) {
-    if (defaultOptions.hasOwnProperty(optionName) && !options.hasOwnProperty(optionName)) {
-      options[optionName] = defaultOptions[optionName];
+  for (const option of defaultOptionsKeys) {
+    if (defaultOptions.hasOwnProperty(option) && !options.hasOwnProperty(option)) {
+      options[option] = defaultOptions[option];
     }
   }
 
@@ -149,6 +149,10 @@ SchemaType.cast = function cast(caster) {
   return this._cast;
 };
 
+SchemaType.set = function set(option, value) {
+  this.defaultOptions[option] = value;
+};
+
 /**
  * Attaches a getter for all instances of this schema type.
  *
diff --git a/test.js b/test.js
new file mode 100644
index 00000000000..3fa25319400
--- /dev/null
+++ b/test.js
@@ -0,0 +1,13 @@
+'use strict';
+const mongoose = require('./');
+const assert = require('assert');
+const {Schema} = mongoose;
+
+mongoose.SchemaTypes.String.set('trim',true);
+mongoose.SchemaTypes.String.set('required',true);
+mongoose.SchemaTypes.String.set('someRandomOption','hello mama');
+
+const userSchema = new Schema({ name: { type: String} });
+assert.ok(userSchema.path('name').options.trim === true);
+assert.ok(userSchema.path('name').options.required === true);
+assert.ok(userSchema.path('name').options.someRandomOption === 'hello mama');
\ No newline at end of file
diff --git a/test/schematype.test.js b/test/schematype.test.js
index f5b6b7c7bac..a46ff80ee2a 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -190,4 +190,34 @@ describe('schematype', function() {
       cloneAndTestDeepEquals();
     });
   });
+
+  describe('set()', () => {
+    describe('SchemaType.set()', function() {
+      it('SchemaType.set, is a function', () => {
+        assert.equal(typeof mongoose.SchemaType.set, 'function');
+      });
+    });
+
+    [
+      mongoose.SchemaTypes.String,
+      mongoose.SchemaTypes.Number,
+      mongoose.SchemaTypes.Boolean,
+      mongoose.SchemaTypes.Array,
+      mongoose.SchemaTypes.Buffer,
+      mongoose.SchemaTypes.Date,
+      mongoose.SchemaTypes.ObjectId,
+      mongoose.SchemaTypes.Mixed,
+      mongoose.SchemaTypes.Decimal128,
+      mongoose.SchemaTypes.Map
+    ].forEach((type) => {
+      it(type.name + ', when given a default option, set its', () => {
+        // Act
+        type.set('required', true);
+        const schema = new mongoose.Schema({test: type});
+
+        // Assert
+        assert.equal(schema.path('test').options.required, true);
+      });
+    });
+  });
 });
diff --git a/test/types.string.test.js b/test/types.string.test.js
deleted file mode 100644
index 390fd184b0b..00000000000
--- a/test/types.string.test.js
+++ /dev/null
@@ -1,29 +0,0 @@
-'use strict';
-
-/**
- * Module dependencies.
- */
-
-const mongoose = require('./common').mongoose;
-
-const assert = require('assert');
-
-/**
- * Test.
- */
-
-describe('types.string', function() {
-  describe('Schema.Types.String.setDefaultOptions(...)', function() {
-    it('when given an option, sets it', () => {
-      // Arrange
-      const mongooseInstance = new mongoose.Mongoose();
-
-      // Act
-      mongooseInstance.Schema.Types.String.setDefaultOption('trim',true);
-      const userSchema = new mongooseInstance.Schema({name:{type:String}});
-
-      // Assert
-      assert.equal(userSchema.path('name').options.trim, true);
-    });
-  });
-});

From 1d93571fc38a056a4e533376ef5724a3b43c018e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:37:35 +0200
Subject: [PATCH 0464/2348] Add default settings to a new mongoose instance

---
 test/schematype.test.js | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/test/schematype.test.js b/test/schematype.test.js
index a46ff80ee2a..b09996acdd6 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -199,16 +199,15 @@ describe('schematype', function() {
     });
 
     [
-      mongoose.SchemaTypes.String,
-      mongoose.SchemaTypes.Number,
-      mongoose.SchemaTypes.Boolean,
-      mongoose.SchemaTypes.Array,
-      mongoose.SchemaTypes.Buffer,
-      mongoose.SchemaTypes.Date,
-      mongoose.SchemaTypes.ObjectId,
-      mongoose.SchemaTypes.Mixed,
-      mongoose.SchemaTypes.Decimal128,
-      mongoose.SchemaTypes.Map
+      mongooseInstance.SchemaTypes.String,
+      mongooseInstance.SchemaTypes.Number,
+      mongooseInstance.SchemaTypes.Boolean,
+      mongooseInstance.SchemaTypes.Buffer,
+      mongooseInstance.SchemaTypes.Date,
+      mongooseInstance.SchemaTypes.ObjectId,
+      mongooseInstance.SchemaTypes.Mixed,
+      mongooseInstance.SchemaTypes.Decimal128,
+      mongooseInstance.SchemaTypes.Map
     ].forEach((type) => {
       it(type.name + ', when given a default option, set its', () => {
         // Act

From b07377513ac6ffe55ac2c933c6fba02c87a890c8 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:38:25 +0200
Subject: [PATCH 0465/2348] Remove .set from SchemaArray

---
 lib/schema/array.js | 23 -----------------------
 1 file changed, 23 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 475de969089..e32cff9bfc5 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -121,8 +121,6 @@ function SchemaArray(key, cast, options, schemaOptions) {
  */
 SchemaArray.schemaName = 'Array';
 
-SchemaArray.defaultOptions = {};
-
 /**
  * Options for all arrays.
  *
@@ -134,27 +132,6 @@ SchemaArray.defaultOptions = {};
 
 SchemaArray.options = { castNonArrays: true };
 
-/**
- * Sets a default option for all Array instances.
- *
- * ####Example:
- *
- *     // Make all arrays have option `required` equal to true.
- *     mongoose.Schema.Array.set('required', true);
- *
- *     const User = mongoose.model('User', new Schema({ test: Array }));
- *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
- *
- * @param {String} option - The option you'd like to set the value for
- * @param {*} value - value for option
- * @return {undefined}
- * @function set
- * @static
- * @api public
- */
-
-SchemaArray.set = SchemaType.set;
-
 /*!
  * Inherits from SchemaType.
  */

From a5c4fb0a3cfc94325d18d7c5eeb45b3c84234f32 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 07:48:09 +0200
Subject: [PATCH 0466/2348] Use a fake option for testing

---
 test/schematype.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/schematype.test.js b/test/schematype.test.js
index b09996acdd6..1d48b298cd2 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -215,7 +215,7 @@ describe('schematype', function() {
         const schema = new mongoose.Schema({test: type});
 
         // Assert
-        assert.equal(schema.path('test').options.required, true);
+        assert.equal(schema.path('test').options.someRandomOption, true);
       });
     });
   });

From d861fa94e9edf6a80cdbf25aa6b0f80f16c11b6f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 17 Jan 2020 08:03:03 +0200
Subject: [PATCH 0467/2348] Default options to an empty object

---
 lib/schematype.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/schematype.js b/lib/schematype.js
index 718dba327b1..2ce17e18c5d 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -44,6 +44,7 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
+  options = options || {};
   const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
 

From fc7d8c8edf05aa87d1555dba3dc6a17fbd7fad7a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 3 Feb 2020 23:23:35 +0200
Subject: [PATCH 0468/2348] Add preoperty for SchemaType.set(...)

---
 lib/schema/array.js     | 23 +++++++++++++++++++++++
 lib/schematype.js       |  3 +++
 test/schematype.test.js | 19 ++++++++++---------
 3 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index e32cff9bfc5..0bb78ad5963 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -121,6 +121,7 @@ function SchemaArray(key, cast, options, schemaOptions) {
  */
 SchemaArray.schemaName = 'Array';
 
+
 /**
  * Options for all arrays.
  *
@@ -132,6 +133,28 @@ SchemaArray.schemaName = 'Array';
 
 SchemaArray.options = { castNonArrays: true };
 
+SchemaArray.defaultOptions = {};
+
+/**
+ * Sets a default option for all Array instances.
+ *
+ * ####Example:
+ *
+ *     // Make all Array instances have `required` of true by default.
+ *     mongoose.Schema.Array.set('required', true);
+ *
+ *     const User = mongoose.model('User', new Schema({ test: Array }));
+ *     new User({ }).validateSync().errors.test.message; // Path `test` is required.
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+SchemaArray.set = SchemaType.set;
+
 /*!
  * Inherits from SchemaType.
  */
diff --git a/lib/schematype.js b/lib/schematype.js
index 2ce17e18c5d..b54d335e516 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -151,6 +151,9 @@ SchemaType.cast = function cast(caster) {
 };
 
 SchemaType.set = function set(option, value) {
+  if (!this.hasOwnProperty('defaultOptions')) {
+    this.defaultOptions = Object.assign({}, this.defaultOptions);
+  }
   this.defaultOptions[option] = value;
 };
 
diff --git a/test/schematype.test.js b/test/schematype.test.js
index 1d48b298cd2..92b7c0a552c 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -199,15 +199,16 @@ describe('schematype', function() {
     });
 
     [
-      mongooseInstance.SchemaTypes.String,
-      mongooseInstance.SchemaTypes.Number,
-      mongooseInstance.SchemaTypes.Boolean,
-      mongooseInstance.SchemaTypes.Buffer,
-      mongooseInstance.SchemaTypes.Date,
-      mongooseInstance.SchemaTypes.ObjectId,
-      mongooseInstance.SchemaTypes.Mixed,
-      mongooseInstance.SchemaTypes.Decimal128,
-      mongooseInstance.SchemaTypes.Map
+      mongoose.SchemaTypes.String,
+      mongoose.SchemaTypes.Number,
+      mongoose.SchemaTypes.Boolean,
+      mongoose.SchemaTypes.Array,
+      mongoose.SchemaTypes.Buffer,
+      mongoose.SchemaTypes.Date,
+      mongoose.SchemaTypes.ObjectId,
+      mongoose.SchemaTypes.Mixed,
+      mongoose.SchemaTypes.Decimal128,
+      mongoose.SchemaTypes.Map
     ].forEach((type) => {
       it(type.name + ', when given a default option, set its', () => {
         // Act

From 00bdfbba5680c6568a3f3f820c1f868c1b8a9e3b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 4 Feb 2020 00:11:44 +0200
Subject: [PATCH 0469/2348] Add useUnifiedTopolgy to homepage example

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 95ae293d79f..f8e80f13025 100644
--- a/index.pug
+++ b/index.pug
@@ -121,7 +121,7 @@ html(lang='en')
         :markdown
           ```javascript
           const mongoose = require('mongoose');
-          mongoose.connect('mongodb://localhost:27017/test', {useNewUrlParser: true});
+          mongoose.connect('mongodb://localhost:27017/test', {useNewUrlParser: true, useUnifiedTopology: true});
 
           const Cat = mongoose.model('Cat', { name: String });
 

From 0166efc64858f5aff5bbe9ea328a6d99e9c27dda Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 4 Feb 2020 00:54:21 +0200
Subject: [PATCH 0470/2348] Add JSDoc to SchemaType.set

---
 lib/schematype.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/lib/schematype.js b/lib/schematype.js
index b54d335e516..94b3befcfd1 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -150,6 +150,23 @@ SchemaType.cast = function cast(caster) {
   return this._cast;
 };
 
+/**
+ * Sets a default option for this schema type.
+ *
+ * ####Example:
+ *
+ *     // Make all strings be trimmed by default
+ *     mongoose.SchemaTypes.String.set('trim', true);
+ *
+ * @param {String} option The name of the option you'd like to set (e.g. trim, lowercase, etc...)
+ * @param {*} value The value of the option you'd like to set.
+ * @return {void}
+ * @static
+ * @receiver SchemaType
+ * @function set
+ * @api public
+ */
+
 SchemaType.set = function set(option, value) {
   if (!this.hasOwnProperty('defaultOptions')) {
     this.defaultOptions = Object.assign({}, this.defaultOptions);

From 6545864170fdaa55e18b9789e8a651318f1715e9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 4 Feb 2020 20:53:00 -0500
Subject: [PATCH 0471/2348] feat(document): add `Document#$op` property to make
 it easier to tell what operation is running in middleware

Fix #8439
---
 lib/document.js                   | 26 ++++++++++++++++++++++++++
 lib/helpers/document/compile.js   |  2 +-
 lib/helpers/model/applyHooks.js   | 18 ++++++++----------
 lib/model.js                      |  8 +++++++-
 lib/plugins/validateBeforeSave.js |  1 +
 test/document.test.js             | 19 +++++++++++++++++++
 test/model.test.js                | 24 ++++++++++++++++++++++++
 7 files changed, 86 insertions(+), 12 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index bcc2cdff695..3c37df45d42 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -155,6 +155,7 @@ function Document(obj, fields, skipId, options) {
 
   this.$__._id = this._id;
   this.$locals = {};
+  this.$op = null;
 
   if (!schema.options.strict && obj) {
     const _this = this;
@@ -269,6 +270,29 @@ Document.prototype.id;
 
 Document.prototype.errors;
 
+/**
+ * A string containing the current operation that Mongoose is executing
+ * on this document. May be `null`, `'save'`, `'validate'`, or `'remove'`.
+ *
+ * ####Example:
+ *
+ *     const doc = new Model({ name: 'test' });
+ *     doc.$op; // null
+ *
+ *     const promise = doc.save();
+ *     doc.$op; // 'save'
+ *
+ *     await promise;
+ *     doc.$op; // null
+ *
+ * @api public
+ * @property $op
+ * @memberOf Document
+ * @instance
+ */
+
+Document.prototype.$op;
+
 /*!
  * ignore
  */
@@ -2028,6 +2052,7 @@ Document.prototype.isDirectSelected = function isDirectSelected(path) {
 
 Document.prototype.validate = function(pathsToValidate, options, callback) {
   let parallelValidate;
+  this.$op = 'validate';
 
   if (this.ownerDocument != null) {
     // Skip parallel validate check for subdocuments
@@ -2057,6 +2082,7 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
 
     this.$__validate(pathsToValidate, options, (error) => {
       this.$__.validating = null;
+      this.$op = null;
       cb(error);
     });
   }, this.constructor.events);
diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index a6450ee258e..ecc4f6f97e1 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -163,7 +163,7 @@ function getOwnPropertyDescriptors(object) {
       delete result[key];
       return;
     }
-    result[key].enumerable = ['isNew', '$__', 'errors', '_doc', '$locals'].indexOf(key) === -1;
+    result[key].enumerable = ['isNew', '$__', 'errors', '_doc', '$locals', '$op'].indexOf(key) === -1;
   });
 
   return result;
diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index c3bedf73e01..c86a7079ef6 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -91,16 +91,14 @@ function applyHooks(model, schema, options) {
 
   model._middleware = middleware;
 
-  objToDecorate.$__save = middleware.
-    createWrapper('save', objToDecorate.$__save, null, kareemOptions);
-
   objToDecorate.$__originalValidate = objToDecorate.$__originalValidate || objToDecorate.$__validate;
-  objToDecorate.$__validate = middleware.
-    createWrapper('validate', objToDecorate.$__originalValidate, null, kareemOptions);
-  objToDecorate.$__remove = middleware.
-    createWrapper('remove', objToDecorate.$__remove, null, kareemOptions);
-  objToDecorate.$__deleteOne = middleware.
-    createWrapper('deleteOne', objToDecorate.$__deleteOne, null, kareemOptions);
+
+  for (const method of ['save', 'validate', 'remove', 'deleteOne']) {
+    const toWrap = method === 'validate' ? '$__originalValidate' : `$__${method}`;
+    const wrapped = middleware.
+      createWrapper(method, objToDecorate[toWrap], null, kareemOptions);
+    objToDecorate[`$__${method}`] = wrapped;
+  }
   objToDecorate.$__init = middleware.
     createWrapperSync('init', objToDecorate.$__init, null, kareemOptions);
 
@@ -134,4 +132,4 @@ function applyHooks(model, schema, options) {
     objToDecorate[`$__${method}`] = middleware.
       createWrapper(method, originalMethod, null, customMethodOptions);
   }
-}
+}
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index 4acd5e0910d..f3a9b04b583 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -444,6 +444,7 @@ function generateVersionError(doc, modifiedPaths) {
 
 Model.prototype.save = function(options, fn) {
   let parallelSave;
+  this.$op = 'save';
 
   if (this.$__.saving) {
     parallelSave = new ParallelSaveError(this);
@@ -479,6 +480,7 @@ Model.prototype.save = function(options, fn) {
       this.$__.saving = undefined;
       delete this.$__.saveOptions;
       delete this.$__.$versionError;
+      this.$op = null;
 
       if (error) {
         this.$__handleReject(error);
@@ -908,12 +910,16 @@ Model.prototype.remove = function remove(options, fn) {
   if (options.hasOwnProperty('session')) {
     this.$session(options.session);
   }
+  this.$op = 'remove';
 
   fn = this.constructor.$handleCallbackError(fn);
 
   return utils.promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
-    this.$__remove(options, cb);
+    this.$__remove(options, (err, res) => {
+      this.$op = null;
+      cb(err, res);
+    });
   }, this.constructor.events);
 };
 
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index cb65577ffa8..6c57d006c4f 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -34,6 +34,7 @@ module.exports = function(schema) {
         null;
       this.validate(validateOptions, function(error) {
         return _this.schema.s.hooks.execPost('save:error', _this, [ _this], { error: error }, function(error) {
+          _this.$op = 'save';
           next(error);
         });
       });
diff --git a/test/document.test.js b/test/document.test.js
index be67a3625e1..e41e8da087f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8647,4 +8647,23 @@ describe('document', function() {
       yield [doc.single.validate(), doc.single.validate()];
     });
   });
+
+  it('sets `Document#op` when calling `validate()` (gh-8439)', function() {
+    const schema = Schema({ name: String });
+    const ops = [];
+    schema.pre('validate', function() {
+      ops.push(this.$op);
+    });
+    schema.post('validate', function() {
+      ops.push(this.$op);
+    });
+
+    const Model = db.model('Test', schema);
+    const doc = new Model({ name: 'test' });
+
+    const promise = doc.validate();
+    assert.equal(doc.$op, 'validate');
+
+    return promise.then(() => assert.deepEqual(ops, ['validate', 'validate']));
+  });
 });
diff --git a/test/model.test.js b/test/model.test.js
index 05dcb3a7b2a..e7b5f122d9a 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6402,4 +6402,28 @@ describe('Model', function() {
       assert.strictEqual(obj.age, 42);
     });
   });
+
+  it('sets correct `Document#op` with `save()` (gh-8439)', function() {
+    const schema = Schema({ name: String });
+    const ops = [];
+    schema.pre('validate', function() {
+      ops.push(this.$op);
+    });
+    schema.pre('save', function() {
+      ops.push(this.$op);
+    });
+    schema.post('validate', function() {
+      ops.push(this.$op);
+    });
+    schema.post('save', function() {
+      ops.push(this.$op);
+    });
+
+    const Model = db.model('Test', schema);
+    const doc = new Model({ name: 'test' });
+
+    return doc.save().then(() => {
+      assert.deepEqual(ops, ['validate', 'validate', 'save', 'save']);
+    });
+  });
 });

From cfaf4e4a1fbd8d8ab8b66ad0e5ea28b7eb90d985 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 4 Feb 2020 22:01:01 -0500
Subject: [PATCH 0472/2348] feat(populate): add `perDocumentLimit` option that
 limits per document in `find()` result, rather than across all documents

Fix #7318
---
 docs/populate.pug                             | 18 +++----
 .../populate/getModelsMapForPopulate.js       |  5 +-
 lib/model.js                                  | 10 +++-
 lib/options/VirtualOptions.js                 | 16 +++++++
 test/model.populate.test.js                   | 47 +++++++++++++++++++
 5 files changed, 85 insertions(+), 11 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index c3e551b322b..0f6a475725d 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -288,16 +288,18 @@ block content
 
     That's because, in order to avoid executing a separate query
     for each document, Mongoose instead queries for fans using
-    `numDocuments * limit` as the limit. As a workaround, you
-    should populate each document individually:
+    `numDocuments * limit` as the limit. If you need the correct
+    `limit`, you should use the `perDocumentLimit` option (new in Mongoose 5.9.0).
+    Just keep in mind that `populate()` will execute a separate query
+    for each story.
 
     ```javascript
-    const stories = await Story.find().sort({ name: 1 });
-    for (const story of stories) {
-      await story.
-        populate({ path: 'fans', options: { limit: 2 } }).
-        execPopulate();
-    }
+    const stories = await Story.find().sort({ name: 1 }).populate({
+      path: 'fans',
+      // Special option that tells Mongoose to execute a separate query
+      // for each `story` to make sure we get 2 fans for each story.
+      perDocumentLimit: 2
+    });
 
     stories[0].fans.length; // 2
     stories[1].fans.length; // 2
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index a61a20bb7b3..f1ab66c6fb3 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -109,6 +109,9 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       if (virtual.options.limit != null && !options.hasOwnProperty('limit')) {
         options.limit = virtual.options.limit;
       }
+      if (virtual.options.perDocumentLimit != null && !options.hasOwnProperty('perDocumentLimit')) {
+        options.perDocumentLimit = virtual.options.perDocumentLimit;
+      }
     } else {
       localField = options.path;
     }
@@ -263,7 +266,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         ids = flat.filter((val, i) => modelNames[i] === modelName);
       }
 
-      if (!available[modelName]) {
+      if (!available[modelName] || currentOptions.perDocumentLimit != null) {
         currentOptions = {
           model: Model
         };
diff --git a/lib/model.js b/lib/model.js
index f3a9b04b583..53e74c26933 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4198,6 +4198,7 @@ Model.geoSearch = function(conditions, options, callback) {
  * @param {boolean} [options.clone=false] When you do `BlogPost.find().populate('author')`, blog posts with the same author will share 1 copy of an `author` doc. Enable this option to make Mongoose clone populated docs before assigning them.
  * @param {Object|Function} [options.match=null] Add an additional filter to the populate query. Can be a filter object containing [MongoDB query syntax](https://docs.mongodb.com/manual/tutorial/query-documents/), or a function that returns a filter object.
  * @param {Boolean} [options.skipInvalidIds=false] By default, Mongoose throws a cast error if `localField` and `foreignField` schemas don't line up. If you enable this option, Mongoose will instead filter out any `localField` properties that cannot be casted to `foreignField`'s schema type.
+ * @param {Number} [options.perDocumentLimit=null] For legacy reasons, `limit` with `populate()` may give incorrect results because it only executes a single query for every document being populated. If you set `perDocumentLimit`, Mongoose will ensure correct `limit` per document by executing a separate query for each document to `populate()`. For example, `.find().populate({ path: 'test', perDocumentLimit: 2 })` will execute 2 additional queries if `.find()` returns 2 documents.
  * @param {Object} [options.options=null] Additional options like `limit` and `lean`.
  * @param {Function} [callback(err,doc)] Optional callback, executed upon completion. Receives `err` and the `doc(s)`.
  * @return {Promise}
@@ -4398,12 +4399,17 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
 
   const queryOptions = Object.assign({
     skip: mod.options.skip,
-    limit: mod.options.limit
+    limit: mod.options.limit,
+    perDocumentLimit: mod.options.perDocumentLimit
   }, mod.options.options);
   if (mod.count) {
     delete queryOptions.skip;
   }
-  if (queryOptions.limit != null) {
+
+  if (queryOptions.perDocumentLimit != null) {
+    queryOptions.limit = queryOptions.perDocumentLimit;
+    delete queryOptions.perDocumentLimit;
+  } else if (queryOptions.limit != null) {
     queryOptions.limit = queryOptions.limit * mod.ids.length;
   }
 
diff --git a/lib/options/VirtualOptions.js b/lib/options/VirtualOptions.js
index 6bce9b08906..a26641459ec 100644
--- a/lib/options/VirtualOptions.js
+++ b/lib/options/VirtualOptions.js
@@ -145,4 +145,20 @@ Object.defineProperty(VirtualOptions.prototype, 'skip', opts);
 
 Object.defineProperty(VirtualOptions.prototype, 'limit', opts);
 
+/**
+ * The `limit` option for `populate()` has [some unfortunate edge cases](/docs/populate.html#query-conditions)
+ * when working with multiple documents, like `.find().populate()`. The
+ * `perDocumentLimit` option makes `populate()` execute a separate query
+ * for each document returned from `find()` to ensure each document
+ * gets up to `perDocumentLimit` populated docs if possible.
+ *
+ * @api public
+ * @property perDocumentLimit
+ * @memberOf VirtualOptions
+ * @type Number
+ * @instance
+ */
+
+Object.defineProperty(VirtualOptions.prototype, 'perDocumentLimit', opts);
+
 module.exports = VirtualOptions;
\ No newline at end of file
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 4cb71d05ef2..49e19a836e9 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9088,6 +9088,53 @@ describe('model: populate:', function() {
     });
   });
 
+  it('correct limit with populate (gh-7318)', function() {
+    const childSchema = Schema({ _id: Number, parentId: 'ObjectId' });
+
+    const parentSchema = Schema({ name: String });
+    parentSchema.virtual('children', {
+      ref: 'Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      justOne: false,
+      options: { sort: { _id: 1 } },
+      perDocumentLimit: 2
+    });
+
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
+
+    return co(function*() {
+      const p = yield Parent.create({ name: 'test' });
+
+      yield Child.create([
+        { _id: 1, parentId: p._id },
+        { _id: 2, parentId: p._id },
+        { _id: 3, parentId: p._id }
+      ]);
+
+      const p2 = yield Parent.create({ name: 'test2' });
+      yield Child.create([
+        { _id: 4, parentId: p2._id },
+        { _id: 5, parentId: p2._id }
+      ]);
+
+      let docs = yield Parent.find().sort({ _id: 1 }).
+        populate({ path: 'children' });
+      assert.equal(docs[0]._id.toString(), p._id.toString());
+      assert.equal(docs[1]._id.toString(), p2._id.toString());
+      assert.deepEqual(docs[0].children.map(c => c._id), [1, 2]);
+      assert.deepEqual(docs[1].children.map(c => c._id), [4, 5]);
+
+      docs = yield Parent.find().sort({ _id: 1 }).
+        populate({ path: 'children', perDocumentLimit: 1 });
+      assert.equal(docs[0]._id.toString(), p._id.toString());
+      assert.equal(docs[1]._id.toString(), p2._id.toString());
+      assert.deepEqual(docs[0].children.map(c => c._id), [1]);
+      assert.deepEqual(docs[1].children.map(c => c._id), [4]);
+    });
+  });
+
   it('works when embedded discriminator array has populated path but not refPath (gh-8527)', function() {
     const Image = db.model('Image', Schema({ imageName: String }));
     const Text = db.model('Text', Schema({ textName: String }));

From 176e50f3d6ae43779cd187e7be0ccaa1135ac0f6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Feb 2020 11:02:17 -0500
Subject: [PATCH 0473/2348] feat(connection): add `Connection#watch()` to watch
 for changes on an entire database

Fix #8425
---
 lib/connection.js          | 54 ++++++++++++++++++++++++++++++++++++++
 lib/cursor/ChangeStream.js | 25 +++++++++---------
 lib/model.js               | 17 +++++++++++-
 test/connection.test.js    | 35 ++++++++++++++++++++++++
 4 files changed, 117 insertions(+), 14 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index cbda36a4e25..6536348ecf9 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -4,6 +4,7 @@
  * Module dependencies.
  */
 
+const ChangeStream = require('./cursor/ChangeStream');
 const EventEmitter = require('events').EventEmitter;
 const Schema = require('./schema');
 const Collection = require('./driver').get().Collection;
@@ -1141,6 +1142,59 @@ Connection.prototype.deleteModel = function(name) {
   return this;
 };
 
+/**
+ * Watches the entire underlying database for changes. Similar to
+ * [`Model.watch()`](/docs/api/model.html#model_Model.watch).
+ *
+ * This function does **not** trigger any middleware. In particular, it
+ * does **not** trigger aggregate middleware.
+ *
+ * The ChangeStream object is an event emitter that emits the following events:
+ *
+ * - 'change': A change occurred, see below example
+ * - 'error': An unrecoverable error occurred. In particular, change streams currently error out if they lose connection to the replica set primary. Follow [this GitHub issue](https://github.com/Automattic/mongoose/issues/6799) for updates.
+ * - 'end': Emitted if the underlying stream is closed
+ * - 'close': Emitted if the underlying stream is closed
+ *
+ * ####Example:
+ *
+ *     const User = conn.model('User', new Schema({ name: String }));
+ *
+ *     const changeStream = conn.watch().on('change', data => console.log(data));
+ *
+ *     // Triggers a 'change' event on the change stream.
+ *     await User.create({ name: 'test' });
+ *
+ * @api public
+ * @param {Array} [pipeline]
+ * @param {Object} [options] passed without changes to [the MongoDB driver's `Db#watch()` function](https://mongodb.github.io/node-mongodb-native/3.4/api/Db.html#watch)
+ * @return {ChangeStream} mongoose-specific change stream wrapper, inherits from EventEmitter
+ */
+
+Connection.prototype.watch = function(pipeline, options) {
+  const disconnectedError = new MongooseError('Connection ' + this.id +
+    ' was disconnected when calling `watch()`');
+
+  const changeStreamThunk = cb => {
+    immediate(() => {
+      if (this.readyState === STATES.connecting) {
+        this.once('open', function() {
+          const driverChangeStream = this.db.watch(pipeline, options);
+          cb(null, driverChangeStream);
+        });
+      } else if (this.readyState === STATES.disconnected && this.db == null) {
+        cb(disconnectedError);
+      } else {
+        const driverChangeStream = this.db.watch(pipeline, options);
+        cb(null, driverChangeStream);
+      }
+    });
+  };
+
+  const changeStream = new ChangeStream(changeStreamThunk, pipeline, options);
+  return changeStream;
+};
+
 /**
  * Returns an array of model names created on this connection.
  * @api public
diff --git a/lib/cursor/ChangeStream.js b/lib/cursor/ChangeStream.js
index 116d7c9ff90..b3445b06bbb 100644
--- a/lib/cursor/ChangeStream.js
+++ b/lib/cursor/ChangeStream.js
@@ -11,26 +11,25 @@ const EventEmitter = require('events').EventEmitter;
  */
 
 class ChangeStream extends EventEmitter {
-  constructor(model, pipeline, options) {
+  constructor(changeStreamThunk, pipeline, options) {
     super();
 
     this.driverChangeStream = null;
     this.closed = false;
+    this.pipeline = pipeline;
+    this.options = options;
+
     // This wrapper is necessary because of buffering.
-    if (model.collection.buffer) {
-      model.collection.addQueue(() => {
-        if (this.closed) {
-          return;
-        }
-        this.driverChangeStream = model.collection.watch(pipeline, options);
-        this._bindEvents();
-        this.emit('ready');
-      });
-    } else {
-      this.driverChangeStream = model.collection.watch(pipeline, options);
+    changeStreamThunk((err, driverChangeStream) => {
+      if (err != null) {
+        this.emit('error', err);
+        return;
+      }
+
+      this.driverChangeStream = driverChangeStream;
       this._bindEvents();
       this.emit('ready');
-    }
+    });
   }
 
   _bindEvents() {
diff --git a/lib/model.js b/lib/model.js
index 53e74c26933..7e8b563c87f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3167,7 +3167,22 @@ Model.create = function create(doc, options, callback) {
 Model.watch = function(pipeline, options) {
   _checkContext(this, 'watch');
 
-  return new ChangeStream(this, pipeline, options);
+  const changeStreamThunk = cb => {
+    if (this.collection.buffer) {
+      this.collection.addQueue(() => {
+        if (this.closed) {
+          return;
+        }
+        const driverChangeStream = this.collection.watch(pipeline, options);
+        cb(null, driverChangeStream);
+      });
+    } else {
+      const driverChangeStream = this.collection.watch(pipeline, options);
+      cb(null, driverChangeStream);
+    }
+  };
+
+  return new ChangeStream(changeStreamThunk, pipeline, options);
 };
 
 /**
diff --git a/test/connection.test.js b/test/connection.test.js
index ecbc07a8fe9..ca2f212b645 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1157,4 +1157,39 @@ describe('connections:', function() {
       assert.equal(err.name, 'MongooseServerSelectionError');
     });
   });
+
+  it('`watch()` on a whole collection (gh-8425)', function() {
+    this.timeout(10000);
+    if (!process.env.REPLICA_SET) {
+      this.skip();
+    }
+
+    return co(function*() {
+      const opts = {
+        useNewUrlParser: true,
+        useUnifiedTopology: true,
+        replicaSet: process.env.REPLICA_SET
+      };
+      const conn = yield mongoose.createConnection('mongodb://localhost:27017/gh8425', opts);
+
+      const Model = conn.model('Test', Schema({ name: String }));
+      yield Model.create({ name: 'test' });
+
+      const changeStream = conn.watch();
+
+      const changes = [];
+      changeStream.on('change', data => {
+        changes.push(data);
+      });
+
+      yield cb => changeStream.on('ready', () => cb());
+
+      const nextChange = new Promise(resolve => changeStream.on('change', resolve));
+      yield Model.create({ name: 'test2' });
+
+      yield nextChange;
+      assert.equal(changes.length, 1);
+      assert.equal(changes[0].operationType, 'insert');
+    });
+  });
 });

From ed37fffec01c9b502e7057b28ee87c889f121105 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 6 Feb 2020 16:59:46 +0200
Subject: [PATCH 0474/2348] Remove mistakenly added file

I mistakenly added this file with my last merged PR.
---
 test.js | 13 -------------
 1 file changed, 13 deletions(-)
 delete mode 100644 test.js

diff --git a/test.js b/test.js
deleted file mode 100644
index 3fa25319400..00000000000
--- a/test.js
+++ /dev/null
@@ -1,13 +0,0 @@
-'use strict';
-const mongoose = require('./');
-const assert = require('assert');
-const {Schema} = mongoose;
-
-mongoose.SchemaTypes.String.set('trim',true);
-mongoose.SchemaTypes.String.set('required',true);
-mongoose.SchemaTypes.String.set('someRandomOption','hello mama');
-
-const userSchema = new Schema({ name: { type: String} });
-assert.ok(userSchema.path('name').options.trim === true);
-assert.ok(userSchema.path('name').options.required === true);
-assert.ok(userSchema.path('name').options.someRandomOption === 'hello mama');
\ No newline at end of file

From b838d1bf411b250c2f114d7024df39952a4c4ddf Mon Sep 17 00:00:00 2001
From: Hugo Ribeiro <hugo.ribeiro@net.com.br>
Date: Fri, 7 Feb 2020 22:03:30 -0300
Subject: [PATCH 0475/2348] refactor(utils): moving lib/utils.promiseOrCallback
 to lib/helpers/promiseOrCallback

Trying to make things less dependent of utils.js
---
 lib/aggregate.js                       |   5 +-
 lib/connection.js                      |   5 +-
 lib/cursor/AggregationCursor.js        |   6 +-
 lib/cursor/QueryCursor.js              |   6 +-
 lib/document.js                        |   5 +-
 lib/helpers/cursor/eachAsync.js        |   5 +-
 lib/helpers/model/applyHooks.js        |   6 +-
 lib/helpers/model/applyStaticHooks.js  |   4 +-
 lib/helpers/promiseOrCallback.js       |  45 ++++++++++
 lib/index.js                           |   3 +-
 lib/model.js                           |  31 +++----
 lib/query.js                           |   5 +-
 lib/types/embedded.js                  |   4 +-
 lib/types/subdocument.js               |   4 +-
 lib/utils.js                           |  44 +---------
 test/helpers/promiseOrCallback.test.js | 110 +++++++++++++++++++++++++
 16 files changed, 205 insertions(+), 83 deletions(-)
 create mode 100644 lib/helpers/promiseOrCallback.js
 create mode 100644 test/helpers/promiseOrCallback.test.js

diff --git a/lib/aggregate.js b/lib/aggregate.js
index ea3b5f1e6a4..4e2b8c6cb12 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -7,6 +7,7 @@
 const AggregationCursor = require('./cursor/AggregationCursor');
 const Query = require('./query');
 const applyGlobalMaxTimeMS = require('./helpers/query/applyGlobalMaxTimeMS');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const util = require('util');
 const utils = require('./utils');
 const read = Query.prototype.read;
@@ -699,7 +700,7 @@ Aggregate.prototype.redact = function(expression, thenExpr, elseExpr) {
 Aggregate.prototype.explain = function(callback) {
   const model = this._model;
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     if (!this._pipeline.length) {
       const err = new Error('Aggregate has empty pipeline');
       return cb(err);
@@ -954,7 +955,7 @@ Aggregate.prototype.exec = function(callback) {
     return new AggregationCursor(this);
   }
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
 
     prepareDiscriminatorPipeline(this);
 
diff --git a/lib/connection.js b/lib/connection.js
index f249b8aaf75..c7d457a3229 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -12,6 +12,7 @@ const MongooseError = require('./error/index');
 const PromiseProvider = require('./promise_provider');
 const TimeoutError = require('./error/timeout');
 const applyPlugins = require('./helpers/schema/applyPlugins');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const get = require('./helpers/get');
 const immediate = require('./helpers/immediate');
 const mongodb = require('mongodb');
@@ -469,7 +470,7 @@ function _wrapConnHelper(fn) {
       Array.prototype.slice.call(arguments);
     const disconnectedError = new MongooseError('Connection ' + this.id +
       ' was disconnected when calling `' + fn.name + '`');
-    return utils.promiseOrCallback(cb, cb => {
+    return promiseOrCallback(cb, cb => {
       // Make it ok to call collection helpers before `mongoose.connect()`
       // as long as `mongoose.connect()` is called on the same tick.
       // Re: gh-8534
@@ -859,7 +860,7 @@ Connection.prototype.close = function(force, callback) {
 
   this.$wasForceClosed = !!force;
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     this._close(force, cb);
   });
 };
diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 03b6912464a..51dd51919cc 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -6,9 +6,9 @@
 
 const MongooseError = require('../error/mongooseError');
 const Readable = require('stream').Readable;
+const promiseOrCallback = require('../helpers/promiseOrCallback');
 const eachAsync = require('../helpers/cursor/eachAsync');
 const util = require('util');
-const utils = require('../utils');
 
 /**
  * An AggregationCursor is a concurrency primitive for processing aggregation
@@ -164,7 +164,7 @@ AggregationCursor.prototype._markError = function(error) {
  */
 
 AggregationCursor.prototype.close = function(callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     this.cursor.close(error => {
       if (error) {
         cb(error);
@@ -187,7 +187,7 @@ AggregationCursor.prototype.close = function(callback) {
  */
 
 AggregationCursor.prototype.next = function(callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     _next(this, cb);
   });
 };
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 4d74dcedf85..de0108a45b8 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -5,10 +5,10 @@
 'use strict';
 
 const Readable = require('stream').Readable;
+const promiseOrCallback = require('../helpers/promiseOrCallback');
 const eachAsync = require('../helpers/cursor/eachAsync');
 const helpers = require('../queryhelpers');
 const util = require('util');
-const utils = require('../utils');
 
 /**
  * A QueryCursor is a concurrency primitive for processing query results
@@ -157,7 +157,7 @@ QueryCursor.prototype._markError = function(error) {
  */
 
 QueryCursor.prototype.close = function(callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     this.cursor.close(error => {
       if (error) {
         cb(error);
@@ -180,7 +180,7 @@ QueryCursor.prototype.close = function(callback) {
  */
 
 QueryCursor.prototype.next = function(callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     _next(this, function(error, doc) {
       if (error) {
         return cb(error);
diff --git a/lib/document.js b/lib/document.js
index bcc2cdff695..c1cc10dda23 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -16,6 +16,7 @@ const StrictModeError = require('./error/strict');
 const ValidationError = require('./error/validation');
 const ValidatorError = require('./error/validator');
 const VirtualType = require('./virtualtype');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const cleanModifiedSubpaths = require('./helpers/document/cleanModifiedSubpaths');
 const compile = require('./helpers/document/compile').compile;
 const defineKey = require('./helpers/document/compile').defineKey;
@@ -2050,7 +2051,7 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
     pathsToValidate = null;
   }
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     if (parallelValidate != null) {
       return cb(parallelValidate);
     }
@@ -3516,7 +3517,7 @@ Document.prototype.populate = function populate() {
  */
 
 Document.prototype.execPopulate = function(callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     this.populate(cb);
   }, this.constructor.events);
 };
diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 7483cc0694e..4ff8ff7ad3b 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -4,7 +4,8 @@
  * Module dependencies.
  */
 
-const utils = require('../../utils');
+
+const promiseOrCallback = require('../promiseOrCallback');
 
 /**
  * Execute `fn` for every document in the cursor. If `fn` returns a promise,
@@ -88,7 +89,7 @@ module.exports = function eachAsync(next, fn, options, callback) {
     }
   };
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     iterate(cb);
   });
 };
diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index c3bedf73e01..e32cd227a8d 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -1,7 +1,7 @@
 'use strict';
 
 const symbols = require('../../schema/symbols');
-const utils = require('../../utils');
+const promiseOrCallback = require('../promiseOrCallback');
 
 /*!
  * ignore
@@ -123,10 +123,10 @@ function applyHooks(model, schema, options) {
     const originalMethod = objToDecorate[method];
     objToDecorate[method] = function() {
       const args = Array.prototype.slice.call(arguments);
-      const cb = utils.last(args);
+      const cb = args.pop();
       const argsWithoutCallback = typeof cb === 'function' ?
         args.slice(0, args.length - 1) : args;
-      return utils.promiseOrCallback(cb, callback => {
+      return promiseOrCallback(cb, callback => {
         return this[`$__${method}`].apply(this,
           argsWithoutCallback.concat([callback]));
       }, model.events);
diff --git a/lib/helpers/model/applyStaticHooks.js b/lib/helpers/model/applyStaticHooks.js
index 88048478905..219e2890318 100644
--- a/lib/helpers/model/applyStaticHooks.js
+++ b/lib/helpers/model/applyStaticHooks.js
@@ -1,7 +1,7 @@
 'use strict';
 
 const middlewareFunctions = require('../query/applyQueryMiddleware').middlewareFunctions;
-const utils = require('../../utils');
+const promiseOrCallback = require('../promiseOrCallback');
 
 module.exports = function applyStaticHooks(model, hooks, statics) {
   const kareemOptions = {
@@ -35,7 +35,7 @@ module.exports = function applyStaticHooks(model, hooks, statics) {
           call(arguments, 0, cb == null ? numArgs : numArgs - 1);
         // Special case: can't use `Kareem#wrap()` because it doesn't currently
         // support wrapped functions that return a promise.
-        return utils.promiseOrCallback(cb, callback => {
+        return promiseOrCallback(cb, callback => {
           hooks.execPre(key, model, args, function(err) {
             if (err != null) {
               return callback(err);
diff --git a/lib/helpers/promiseOrCallback.js b/lib/helpers/promiseOrCallback.js
new file mode 100644
index 00000000000..a1aff55df61
--- /dev/null
+++ b/lib/helpers/promiseOrCallback.js
@@ -0,0 +1,45 @@
+'use strict';
+
+const PromiseProvider = require('../promise_provider');
+
+const emittedSymbol = Symbol.for('mongoose:emitted');
+
+module.exports = function promiseOrCallback(callback, fn, ee) {
+  if (typeof callback === 'function') {
+    return fn(function(error) {
+      if (error != null) {
+        if (ee != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
+          error[emittedSymbol] = true;
+          ee.emit('error', error);
+        }
+        try {
+          callback(error);
+        } catch (error) {
+          return process.nextTick(() => {
+            throw error;
+          });
+        }
+        return;
+      }
+      callback.apply(this, arguments);
+    });
+  }
+
+  const Promise = PromiseProvider.get();
+
+  return new Promise((resolve, reject) => {
+    fn(function(error, res) {
+      if (error != null) {
+        if (ee != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
+          error[emittedSymbol] = true;
+          ee.emit('error', error);
+        }
+        return reject(error);
+      }
+      if (arguments.length > 2) {
+        return resolve(Array.prototype.slice.call(arguments, 1));
+      }
+      resolve(res);
+    });
+  });
+};
\ No newline at end of file
diff --git a/lib/index.js b/lib/index.js
index 67aa43acd6e..573078e4fb0 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -27,6 +27,7 @@ const Query = require('./query');
 const Model = require('./model');
 const applyPlugins = require('./helpers/schema/applyPlugins');
 const get = require('./helpers/get');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const legacyPluralize = require('mongoose-legacy-pluralize');
 const utils = require('./utils');
 const pkg = require('../package.json');
@@ -343,7 +344,7 @@ Mongoose.prototype.connect = function(uri, options, callback) {
 Mongoose.prototype.disconnect = function(callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     let remaining = _mongoose.connections.length;
     if (remaining <= 0) {
       return cb(null);
diff --git a/lib/model.js b/lib/model.js
index 08d41b72253..7719bf33f93 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -43,6 +43,7 @@ const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
 const modifiedPaths = require('./helpers/update/modifiedPaths');
 const mpath = require('mpath');
 const parallelLimit = require('./helpers/parallelLimit');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const parseProjection = require('./helpers/projection/parseProjection');
 const util = require('util');
 const utils = require('./utils');
@@ -465,7 +466,7 @@ Model.prototype.save = function(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return utils.promiseOrCallback(fn, cb => {
+  return promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
 
     if (parallelSave) {
@@ -911,7 +912,7 @@ Model.prototype.remove = function remove(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return utils.promiseOrCallback(fn, cb => {
+  return promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
     this.$__remove(options, cb);
   }, this.constructor.events);
@@ -947,7 +948,7 @@ Model.prototype.deleteOne = function deleteOne(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return utils.promiseOrCallback(fn, cb => {
+  return promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
     this.$__deleteOne(options, cb);
   }, this.constructor.events);
@@ -1294,7 +1295,7 @@ Model.createCollection = function createCollection(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
@@ -1335,7 +1336,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     this.createCollection(err => {
@@ -1373,7 +1374,7 @@ Model.cleanIndexes = function cleanIndexes(callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     const collection = this.collection;
 
     this.listIndexes((err, indexes) => {
@@ -1490,7 +1491,7 @@ Model.listIndexes = function init(callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     // Buffering
@@ -1541,7 +1542,7 @@ Model.ensureIndexes = function ensureIndexes(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     _ensureIndexes(this, options || {}, error => {
@@ -3050,7 +3051,7 @@ Model.create = function create(doc, options, callback) {
     }
   }
 
-  return utils.promiseOrCallback(cb, cb => {
+  return promiseOrCallback(cb, cb => {
     cb = this.$wrapCallback(cb);
     if (args.length === 0) {
       return cb(null);
@@ -3236,7 +3237,7 @@ Model.insertMany = function(arr, options, callback) {
     callback = options;
     options = null;
   }
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     this.$__insertMany(arr, options, cb);
   }, this.events);
 };
@@ -3460,7 +3461,7 @@ Model.bulkWrite = function(ops, options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     each(validations, (fn, cb) => fn(cb), error => {
       if (error) {
@@ -3825,7 +3826,7 @@ Model.mapReduce = function mapReduce(o, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     if (!Model.mapReduce.schema) {
@@ -3965,7 +3966,7 @@ Model.aggregate = function aggregate(pipeline, callback) {
  */
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     const schema = this.schema;
     let paths = Object.keys(schema.paths);
 
@@ -4075,7 +4076,7 @@ Model.geoSearch = function(conditions, options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     let error;
     if (conditions === undefined || !utils.isObject(conditions)) {
@@ -4211,7 +4212,7 @@ Model.populate = function(docs, paths, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     _populate(_this, docs, paths, cache, cb);
   }, this.events);
diff --git a/lib/query.js b/lib/query.js
index 6837516aa36..4e6d007aa10 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -18,6 +18,7 @@ const castArrayFilters = require('./helpers/update/castArrayFilters');
 const castUpdate = require('./helpers/query/castUpdate');
 const completeMany = require('./helpers/query/completeMany');
 const get = require('./helpers/get');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const hasDollarKeys = require('./helpers/query/hasDollarKeys');
 const helpers = require('./queryhelpers');
@@ -3754,7 +3755,7 @@ function _updateThunk(op, callback) {
  */
 
 Query.prototype.validate = function validate(castedDoc, options, isOverwriting, callback) {
-  return utils.promiseOrCallback(callback, cb => {
+  return promiseOrCallback(callback, cb => {
     try {
       if (isOverwriting) {
         castedDoc.validate(cb);
@@ -4339,7 +4340,7 @@ Query.prototype.exec = function exec(op, callback) {
 
   callback = this.model.$handleCallbackError(callback);
 
-  return utils.promiseOrCallback(callback, (cb) => {
+  return promiseOrCallback(callback, (cb) => {
     cb = this.model.$wrapCallback(cb);
 
     if (!_this.op) {
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 585c333381b..0201d7660a8 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -12,7 +12,7 @@ const ValidationError = require('../error/validation');
 const immediate = require('../helpers/immediate');
 const internalToObjectOptions = require('../options').internalToObjectOptions;
 const get = require('../helpers/get');
-const utils = require('../utils');
+const promiseOrCallback = require('../helpers/promiseOrCallback');
 const util = require('util');
 
 const documentArrayParent = require('../helpers/symbols').documentArrayParent;
@@ -146,7 +146,7 @@ EmbeddedDocument.prototype.save = function(options, fn) {
       'if you\'re sure this behavior is right for your app.');
   }
 
-  return utils.promiseOrCallback(fn, cb => {
+  return promiseOrCallback(fn, cb => {
     this.$__save(cb);
   });
 };
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index b360b6982d1..f6bc8cd8ee8 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -3,7 +3,7 @@
 const Document = require('../document');
 const immediate = require('../helpers/immediate');
 const internalToObjectOptions = require('../options').internalToObjectOptions;
-const utils = require('../utils');
+const promiseOrCallback = require('../helpers/promiseOrCallback');
 
 const documentArrayParent = require('../helpers/symbols').documentArrayParent;
 
@@ -76,7 +76,7 @@ Subdocument.prototype.save = function(options, fn) {
       'if you\'re sure this behavior is right for your app.');
   }
 
-  return utils.promiseOrCallback(fn, cb => {
+  return promiseOrCallback(fn, cb => {
     this.$__save(cb);
   });
 };
diff --git a/lib/utils.js b/lib/utils.js
index 1412dcd8980..7d65e1ba1c9 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -7,17 +7,15 @@
 const Decimal = require('./types/decimal128');
 const ObjectId = require('./types/objectid');
 const PopulateOptions = require('./options/PopulateOptions');
-const PromiseProvider = require('./promise_provider');
 const cloneRegExp = require('regexp-clone');
 const get = require('./helpers/get');
+const promiseOrCallback = require('./helpers/promiseOrCallback');
 const sliced = require('sliced');
 const mpath = require('mpath');
 const ms = require('ms');
 const symbols = require('./helpers/symbols');
 const Buffer = require('safe-buffer').Buffer;
 
-const emittedSymbol = Symbol.for('mongoose:emitted');
-
 let MongooseBuffer;
 let MongooseArray;
 let Document;
@@ -256,45 +254,7 @@ const clone = exports.clone;
  * ignore
  */
 
-exports.promiseOrCallback = function promiseOrCallback(callback, fn, ee) {
-  if (typeof callback === 'function') {
-    return fn(function(error) {
-      if (error != null) {
-        if (ee != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
-          error[emittedSymbol] = true;
-          ee.emit('error', error);
-        }
-        try {
-          callback(error);
-        } catch (error) {
-          return process.nextTick(() => {
-            throw error;
-          });
-        }
-        return;
-      }
-      callback.apply(this, arguments);
-    });
-  }
-
-  const Promise = PromiseProvider.get();
-
-  return new Promise((resolve, reject) => {
-    fn(function(error, res) {
-      if (error != null) {
-        if (ee != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
-          error[emittedSymbol] = true;
-          ee.emit('error', error);
-        }
-        return reject(error);
-      }
-      if (arguments.length > 2) {
-        return resolve(Array.prototype.slice.call(arguments, 1));
-      }
-      resolve(res);
-    });
-  });
-};
+exports.promiseOrCallback = promiseOrCallback
 
 /*!
  * ignore
diff --git a/test/helpers/promiseOrCallback.test.js b/test/helpers/promiseOrCallback.test.js
new file mode 100644
index 00000000000..a1111902497
--- /dev/null
+++ b/test/helpers/promiseOrCallback.test.js
@@ -0,0 +1,110 @@
+'use strict';
+
+const assert = require('assert');
+const promiseOrCallback = require('../../lib/helpers/promiseOrCallback');
+
+describe('promiseOrCallback()', () => {
+  const myError = new Error('This is My Error');
+  const myRes = 'My Res';
+  const myOtherArg = 'My Other Arg';
+
+  describe('apply callback', () => {
+    it('without error', (done) => {
+      promiseOrCallback(
+        (error, arg, otherArg) => {
+          assert.equal(arg, myRes);
+          assert.equal(otherArg, myOtherArg);
+          assert.equal(error, undefined);
+          done();
+        },
+        (fn) => { fn(null, myRes, myOtherArg); }
+      );
+    });
+
+    describe('with error', () => {
+      it('without event emitter', (done) => {
+        promiseOrCallback(
+          (error) => {
+            assert.equal(error, myError);
+            done();
+          },
+          (fn) => { fn(myError); }
+        );
+      });
+
+      it('with event emitter', (done) => {
+        promiseOrCallback(
+          () => { },
+          (fn) => { return fn(myError); },
+          {
+            listeners: () => [1],
+            emit: (eventType, error) => {
+              assert.equal(eventType, 'error');
+              assert.equal(error, myError);
+              done();
+            }
+          }
+        );
+      });
+    });
+  });
+
+  describe('chain promise', () => {
+    describe('without error', () => {
+      it('two args', (done) => {
+        const promise = promiseOrCallback(
+          null,
+          (fn) => { fn(null, myRes); }
+        );
+        promise.then((res) => {
+          assert.equal(res, myRes);
+          done();
+        });
+      });
+
+      it('more args', (done) => {
+        const promise = promiseOrCallback(
+          null,
+          (fn) => { fn(null, myRes, myOtherArg); }
+        );
+        promise.then((args) => {
+          assert.equal(args[0], myRes);
+          assert.equal(args[1], myOtherArg);
+          done();
+        });
+      });
+    });
+
+    describe('with error', () => {
+      it('without event emitter', (done) => {
+        const promise = promiseOrCallback(
+          null,
+          (fn) => { fn(myError); }
+        );
+        promise.catch((error) => {
+          assert.equal(error, myError);
+          done();
+        });
+      });
+
+
+      it('with event emitter', (done) => {
+        const promise = promiseOrCallback(
+          null,
+          (fn) => { return fn(myError); },
+          {
+            listeners: () => [1],
+            emit: (eventType, error) => {
+              assert.equal(eventType, 'error');
+              assert.equal(error, myError);
+            }
+          }
+        );
+        promise.catch((error) => {
+          assert.equal(error, myError);
+          done();
+        });
+      });
+    });
+  });
+});
\ No newline at end of file

From a30c8faa6383e9a5a694f9a89ab0579d9cfe3928 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 Feb 2020 22:00:46 -0800
Subject: [PATCH 0476/2348] docs(populate): clean up typos re: #8572

---
 docs/populate.pug | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index c3e551b322b..a3620cffb1e 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -150,7 +150,7 @@ block content
     story.populated('author'); // truthy
 
     story.depopulate('author'); // Make `author` not populated anymore
-    story.populated('author'); // falsy
+    story.populated('author'); // undefined
     ```
 
     A common reason for checking whether a path is populated is getting the `author`
@@ -162,7 +162,7 @@ block content
     story.author._id; // ObjectId
 
     story.depopulate('author'); // Make `author` not populated anymore
-    story.populated('author'); // falsy
+    story.populated('author'); // undefined
 
     story.author instanceof ObjectId; // true
     story.author._id; // ObjectId, because Mongoose adds a special getter

From 4a627a806aaa283afe51b8aa555511a9411bd232 Mon Sep 17 00:00:00 2001
From: hugosenari <hugosenari@gmail.com>
Date: Mon, 10 Feb 2020 10:44:05 -0300
Subject: [PATCH 0477/2348] refactor(utils): fix eslint coma

---
 lib/utils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/utils.js b/lib/utils.js
index 7d65e1ba1c9..545b00600eb 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -254,7 +254,7 @@ const clone = exports.clone;
  * ignore
  */
 
-exports.promiseOrCallback = promiseOrCallback
+exports.promiseOrCallback = promiseOrCallback;
 
 /*!
  * ignore

From 3f0473abf6188d709ba694a378631759e7d64cfe Mon Sep 17 00:00:00 2001
From: hugosenari <hugosenari@gmail.com>
Date: Mon, 10 Feb 2020 11:48:48 -0300
Subject: [PATCH 0478/2348] refactor(eachAsync): removing trailing space

---
 lib/helpers/cursor/eachAsync.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 4ff8ff7ad3b..c50d02af34a 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -4,7 +4,6 @@
  * Module dependencies.
  */
 
-
 const promiseOrCallback = require('../promiseOrCallback');
 
 /**

From a746435095929596e77e953e5a2c61095b61bac6 Mon Sep 17 00:00:00 2001
From: hugosenari <hugosenari@gmail.com>
Date: Mon, 10 Feb 2020 11:50:09 -0300
Subject: [PATCH 0479/2348] refactor(applyHooks): fix poping last arg from args
 remove from args

---
 lib/helpers/model/applyHooks.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index e32cd227a8d..2a30052a7ce 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -123,7 +123,7 @@ function applyHooks(model, schema, options) {
     const originalMethod = objToDecorate[method];
     objToDecorate[method] = function() {
       const args = Array.prototype.slice.call(arguments);
-      const cb = args.pop();
+      const cb = args.slice(-1).pop();
       const argsWithoutCallback = typeof cb === 'function' ?
         args.slice(0, args.length - 1) : args;
       return promiseOrCallback(cb, callback => {

From 7de41dc76141c03adc475155394c808819c4518d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 Feb 2020 15:58:13 -0800
Subject: [PATCH 0480/2348] feat(timestamps): allow setting `currentTime`
 option for setting custom function to get the current time

Fix #3957
---
 docs/guide.pug                 | 18 ++++++++++++++++
 lib/schema.js                  | 19 ++++++++++++-----
 test/schema.timestamps.test.js | 39 ++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+), 5 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 87901d31704..f2ea7211345 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -977,6 +977,24 @@ block content
     ]);
     ```
 
+    By default, Mongoose uses the current time `new Date()` to get
+    the current time. But if you want to overwrite the function
+    Mongoose uses to get the current time, you can set the
+    `timestamps.currentTime` option. Mongoose will call the
+    `timestamps.currentTime` function whenever it needs to get
+    the current time.
+
+    ```javascript
+    const schema = Schema({
+      createdAt: Number,
+      updatedAt: Number,
+      name: String
+    }, {
+      // Make Mongoose use Unix time (seconds since Jan 1, 1970)
+      timestamps: { currentTime: () => Math.floor(Date.now() / 1000) }
+    });
+    ```
+
     <h3 id="useNestedStrict"><a href="#useNestedStrict">option: useNestedStrict</a></h3>
 
     Write operations like `update()`, `updateOne()`, `updateMany()`,
diff --git a/lib/schema.js b/lib/schema.js
index 06cd1d4341b..328995731c2 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1159,6 +1159,9 @@ Schema.prototype.setupTimestamp = function(timestamps) {
 
   const createdAt = handleTimestampOption(timestamps, 'createdAt');
   const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+  const currentTime = timestamps != null && timestamps.hasOwnProperty('currentTime') ?
+    timestamps.currentTime :
+    null;
   const schemaAdditions = {};
 
   this.$timestamps = { createdAt: createdAt, updatedAt: updatedAt };
@@ -1182,8 +1185,9 @@ Schema.prototype.setupTimestamp = function(timestamps) {
     const skipUpdatedAt = timestampOption != null && timestampOption.updatedAt === false;
     const skipCreatedAt = timestampOption != null && timestampOption.createdAt === false;
 
-    const defaultTimestamp = (this.ownerDocument ? this.ownerDocument() : this).
-      constructor.base.now();
+    const defaultTimestamp = currentTime != null ?
+      currentTime() :
+      (this.ownerDocument ? this.ownerDocument() : this).constructor.base.now();
     const auto_id = this._id && this._id.auto;
 
     if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.isSelected(createdAt)) {
@@ -1206,11 +1210,14 @@ Schema.prototype.setupTimestamp = function(timestamps) {
   });
 
   this.methods.initializeTimestamps = function() {
+    const ts = currentTime != null ?
+      currentTime() :
+      this.constructor.base.now();
     if (createdAt && !this.get(createdAt)) {
-      this.set(createdAt, new Date());
+      this.set(createdAt, ts);
     }
     if (updatedAt && !this.get(updatedAt)) {
-      this.set(updatedAt, new Date());
+      this.set(updatedAt, ts);
     }
     return this;
   };
@@ -1225,7 +1232,9 @@ Schema.prototype.setupTimestamp = function(timestamps) {
   this.pre('updateMany', opts, _setTimestampsOnUpdate);
 
   function _setTimestampsOnUpdate(next) {
-    const now = this.model.base.now();
+    const now = currentTime != null ?
+      currentTime() :
+      this.model.base.now();
     applyTimestampsToUpdate(now, createdAt, updatedAt, this.getUpdate(),
       this.options, this.schema);
     applyTimestampsToChildren(now, this.getUpdate(), this.model.schema);
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index 60cc3630456..d11e4379e62 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -360,4 +360,43 @@ describe('schema options.timestamps', function() {
       return Cat.deleteMany({});
     });
   });
+
+  it('timestamps with number types (gh-3957)', function() {
+    const schema = Schema({
+      createdAt: Number,
+      updatedAt: Number,
+      name: String
+    }, { timestamps: true });
+    const Model = conn.model('gh3957', schema);
+    const start = Date.now();
+
+    return co(function*() {
+      const doc = yield Model.create({ name: 'test' });
+
+      assert.equal(typeof doc.createdAt, 'number');
+      assert.equal(typeof doc.updatedAt, 'number');
+      assert.ok(doc.createdAt >= start);
+      assert.ok(doc.updatedAt >= start);
+    });
+  });
+
+  it('timestamps with custom timestamp (gh-3957)', function() {
+    const schema = Schema({
+      createdAt: Number,
+      updatedAt: Number,
+      name: String
+    }, {
+      timestamps: { currentTime: () => 42 }
+    });
+    const Model = conn.model('gh3957_0', schema);
+
+    return co(function*() {
+      const doc = yield Model.create({ name: 'test' });
+
+      assert.equal(typeof doc.createdAt, 'number');
+      assert.equal(typeof doc.updatedAt, 'number');
+      assert.equal(doc.createdAt, 42);
+      assert.equal(doc.updatedAt, 42);
+    });
+  });
 });

From 9a68a2184df99d1c41ba862bdb4939a96ce4c37c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 Feb 2020 17:49:33 -0800
Subject: [PATCH 0481/2348] feat(schematype): enable setting `transform` option
 on individual schematypes

Fix #8403
---
 lib/document.js                  | 41 ++++++++++++++++++++++++++++++++
 lib/index.js                     | 14 +++++++++++
 lib/options/SchemaTypeOptions.js | 29 ++++++++++++++++++++++
 test/document.test.js            | 29 ++++++++++++++++++++++
 4 files changed, 113 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 3c37df45d42..e401bff5fcf 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2996,6 +2996,10 @@ Document.prototype.$toObject = function(options, json) {
   // child schema has a transform (this.schema.options.toObject) In this case,
   // we need to adjust options.transform to be the child schema's transform and
   // not the parent schema's
+  if (transform) {
+    applySchemaTypeTransforms(this, ret, gettersOptions, options);
+  }
+
   if (transform === true || (schemaOptions.toObject && transform)) {
     const opts = options.json ? schemaOptions.toJSON : schemaOptions.toObject;
 
@@ -3309,6 +3313,43 @@ function applyGetters(self, json, options) {
   return json;
 }
 
+/*!
+ * Applies schema type transforms to `json`.
+ *
+ * @param {Document} self
+ * @param {Object} json
+ * @return {Object} `json`
+ */
+
+function applySchemaTypeTransforms(self, json) {
+  const schema = self.schema;
+  const paths = Object.keys(schema.paths);
+  const cur = self._doc;
+
+  if (!cur) {
+    return json;
+  }
+
+  for (const path of paths) {
+    const schematype = schema.paths[path];
+    if (typeof schematype.options.transform === 'function') {
+      const val = self.get(path);
+      json[path] = schematype.options.transform.call(self, val);
+    } else if (schematype.$embeddedSchemaType != null &&
+        typeof schematype.$embeddedSchemaType.options.transform === 'function') {
+      const vals = [].concat(self.get(path));
+      const transform = schematype.$embeddedSchemaType.options.transform;
+      for (let i = 0; i < vals.length; ++i) {
+        vals[i] = transform.call(self, vals[i]);
+      }
+
+      json[path] = vals;
+    }
+  }
+
+  return json;
+}
+
 /**
  * The return value of this method is used in calls to JSON.stringify(doc).
  *
diff --git a/lib/index.js b/lib/index.js
index 67aa43acd6e..4292bea6961 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -1014,6 +1014,20 @@ Mongoose.prototype.Decimal128 = SchemaTypes.Decimal128;
 
 Mongoose.prototype.Mixed = SchemaTypes.Mixed;
 
+/**
+ * The Mongoose Date [SchemaType](/docs/schematypes.html).
+ *
+ * ####Example:
+ *
+ *     const schema = new Schema({ test: Date });
+ *     schema.path('test') instanceof mongoose.Date; // true
+ *
+ * @property Date
+ * @api public
+ */
+
+Mongoose.prototype.Date = SchemaTypes.Date;
+
 /**
  * The Mongoose Number [SchemaType](/docs/schematypes.html). Used for
  * declaring paths in your schema that Mongoose should cast to numbers.
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 898738d533f..7e616d0e6c6 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -200,4 +200,33 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'sparse', opts);
 
 Object.defineProperty(SchemaTypeOptions.prototype, 'text', opts);
 
+/**
+ * Define a transform function for this individual schema type.
+ * Only called when calling `toJSON()` or `toObject()`.
+ *
+ * ####Example:
+ *
+ *     const schema = Schema({
+ *       myDate: {
+ *         type: Date,
+ *         transform: v => v.getFullYear()
+ *       }
+ *     });
+ *     const Model = mongoose.model('Test', schema);
+ *
+ *     const doc = new Model({ myDate: new Date('2019/06/01') });
+ *     doc.myDate instanceof Date; // true
+ *
+ *     const res = doc.toObject({ transform: true });
+ *     res.myDate; // 2019
+ *
+ * @api public
+ * @property transform
+ * @memberOf SchemaTypeOptions
+ * @type Function
+ * @instance
+ */
+
+Object.defineProperty(SchemaTypeOptions.prototype, 'transform', opts);
+
 module.exports = SchemaTypeOptions;
\ No newline at end of file
diff --git a/test/document.test.js b/test/document.test.js
index e41e8da087f..57ef389a982 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8666,4 +8666,33 @@ describe('document', function() {
 
     return promise.then(() => assert.deepEqual(ops, ['validate', 'validate']));
   });
+
+  it('schema-level transform (gh-8403)', function() {
+    const schema = Schema({
+      myDate: {
+        type: Date,
+        transform: v => v.getFullYear()
+      },
+      dates: [{
+        type: Date,
+        transform: v => v.getFullYear()
+      }],
+      arr: [{
+        myDate: {
+          type: Date,
+          transform: v => v.getFullYear()
+        }
+      }]
+    });
+    const Model = db.model('Test', schema);
+
+    const doc = new Model({
+      myDate: new Date('2015/06/01'),
+      dates: [new Date('2016/06/01')],
+      arr: [{ myDate: new Date('2017/06/01') }]
+    });
+    assert.equal(doc.toObject({ transform: true }).myDate, '2015');
+    assert.equal(doc.toObject({ transform: true }).dates[0], '2016');
+    //assert.equal(doc.toObject({ transform: true }).arr[0].myDate, '2017');
+  });
 });

From f2e4cd3accadbfed0cc261f448cb1dbab0c430e2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 Feb 2020 17:55:48 -0800
Subject: [PATCH 0482/2348] test: fix tests re: #8403

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index e401bff5fcf..fcf64affc47 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3323,7 +3323,7 @@ function applyGetters(self, json, options) {
 
 function applySchemaTypeTransforms(self, json) {
   const schema = self.schema;
-  const paths = Object.keys(schema.paths);
+  const paths = Object.keys(schema.paths || {});
   const cur = self._doc;
 
   if (!cur) {

From 2c6546da4199e027374f5fcfc59046564bbe89a5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 12 Feb 2020 11:14:27 -0500
Subject: [PATCH 0483/2348] fix(query): correctly cast dbref `$id` with
 `$elemMatch`

Fix #8577
---
 lib/cast.js                         |  7 +++----
 lib/helpers/query/castFilterPath.js |  8 ++++----
 lib/helpers/query/isOperator.js     | 11 +++++++++++
 lib/schema/array.js                 |  3 ++-
 test/query.test.js                  | 22 ++++++++++++++++++++++
 5 files changed, 42 insertions(+), 9 deletions(-)
 create mode 100644 lib/helpers/query/isOperator.js

diff --git a/lib/cast.js b/lib/cast.js
index 94bdb1d2b9e..da847433e94 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -8,6 +8,7 @@ const StrictModeError = require('./error/strict');
 const Types = require('./schema/index');
 const castTextSearch = require('./schema/operators/text');
 const get = require('./helpers/get');
+const isOperator = require('./helpers/query/isOperator');
 const util = require('util');
 const utils = require('./utils');
 
@@ -252,9 +253,7 @@ module.exports = function cast(schema, obj, options, context) {
       } else if (val == null) {
         continue;
       } else if (val.constructor.name === 'Object') {
-        any$conditionals = Object.keys(val).some(function(k) {
-          return k.startsWith('$') && k !== '$id' && k !== '$ref';
-        });
+        any$conditionals = Object.keys(val).some(isOperator);
 
         if (!any$conditionals) {
           obj[path] = schematype.castForQueryWrapper({
@@ -274,7 +273,7 @@ module.exports = function cast(schema, obj, options, context) {
             if ($cond === '$not') {
               if (nested && schematype && !schematype.caster) {
                 _keys = Object.keys(nested);
-                if (_keys.length && _keys[0].startsWith('$')) {
+                if (_keys.length && isOperator(_keys[0])) {
                   for (const key in nested) {
                     nested[key] = schematype.castForQueryWrapper({
                       $conditional: key,
diff --git a/lib/helpers/query/castFilterPath.js b/lib/helpers/query/castFilterPath.js
index cf9b4c5f5fd..74ff1c2aaf2 100644
--- a/lib/helpers/query/castFilterPath.js
+++ b/lib/helpers/query/castFilterPath.js
@@ -1,10 +1,10 @@
 'use strict';
 
+const isOperator = require('./isOperator');
+
 module.exports = function castFilterPath(query, schematype, val) {
   const ctx = query;
-  const any$conditionals = Object.keys(val).some(function(k) {
-    return k.startsWith('$') && k !== '$id' && k !== '$ref';
-  });
+  const any$conditionals = Object.keys(val).some(isOperator);
 
   if (!any$conditionals) {
     return schematype.castForQueryWrapper({
@@ -24,7 +24,7 @@ module.exports = function castFilterPath(query, schematype, val) {
     if ($cond === '$not') {
       if (nested && schematype && !schematype.caster) {
         const _keys = Object.keys(nested);
-        if (_keys.length && _keys[0].startsWith('$')) {
+        if (_keys.length && isOperator(_keys[0])) {
           for (const key in nested) {
             nested[key] = schematype.castForQueryWrapper({
               $conditional: key,
diff --git a/lib/helpers/query/isOperator.js b/lib/helpers/query/isOperator.js
new file mode 100644
index 00000000000..29bc37a82c6
--- /dev/null
+++ b/lib/helpers/query/isOperator.js
@@ -0,0 +1,11 @@
+'use strict';
+
+const specialKeys = new Set([
+  '$ref',
+  '$id',
+  '$db'
+]);
+
+module.exports = function isOperator(path) {
+  return path.startsWith('$') && !specialKeys.has(path);
+}
\ No newline at end of file
diff --git a/lib/schema/array.js b/lib/schema/array.js
index e32cff9bfc5..d65525df13b 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -13,6 +13,7 @@ const CastError = SchemaType.CastError;
 const Mixed = require('./mixed');
 const cast = require('../cast');
 const get = require('../helpers/get');
+const isOperator = require('../helpers/query/isOperator');
 const util = require('util');
 const utils = require('../utils');
 const castToNumber = require('./operators/helpers').castToNumber;
@@ -438,7 +439,7 @@ function cast$elemMatch(val) {
   for (let i = 0; i < numKeys; ++i) {
     const key = keys[i];
     const value = val[key];
-    if (key.startsWith('$') && value) {
+    if (isOperator(key) && value != null) {
       val[key] = this.castForQuery(key, value);
     }
   }
diff --git a/test/query.test.js b/test/query.test.js
index 0c81a154d70..f17c6aa57a0 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3594,4 +3594,26 @@ describe('Query', function() {
       assert.equal(doc.token, 'rightToken');
     });
   });
+
+  it('casts $elemMatch with dbrefs (gh-8577)', function() {
+    const ChatSchema = new Schema({
+      members: [{
+        $ref: String,
+        $id: mongoose.ObjectId,
+        $db: String
+      }]
+    });
+    const Chat = db.model('Test', ChatSchema);
+
+    return co(function*() {
+      const doc = yield Chat.create({
+        members: [{ $ref: 'foo', $id: new mongoose.Types.ObjectId(), $db: 'foo' }]
+      });
+
+      const res = yield Chat.findOne({
+        members: { $elemMatch: { $id: doc.members[0].$id } }
+      });
+      assert.ok(res);
+    });
+  });
 });

From e93d459a0bfa05c711c83c65e71ea6bcdce3474f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 12 Feb 2020 11:18:14 -0500
Subject: [PATCH 0484/2348] style: fix lint

---
 lib/helpers/query/isOperator.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/query/isOperator.js b/lib/helpers/query/isOperator.js
index 29bc37a82c6..3b9813920ff 100644
--- a/lib/helpers/query/isOperator.js
+++ b/lib/helpers/query/isOperator.js
@@ -8,4 +8,4 @@ const specialKeys = new Set([
 
 module.exports = function isOperator(path) {
   return path.startsWith('$') && !specialKeys.has(path);
-}
\ No newline at end of file
+};
\ No newline at end of file

From ae2f58d6d750a90b40ff8176bf69356ca2029b8e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 12 Feb 2020 13:12:12 -0500
Subject: [PATCH 0485/2348] test(populate): repro #8553

---
 test/model.populate.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index edbcbc2cf34..5708ea5bc3c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9076,4 +9076,31 @@ describe('model: populate:', function() {
       assert.deepEqual(res.list[3].data, { title: 'test' });
     });
   });
+
+  it('handles populating embedded discriminators with `refPath` when none of the subdocs have `refPath` (gh-8553)', function() {
+    const ItemSchema = new Schema({ objectType: String },
+      { discriminatorKey: 'objectType', _id: false });
+    const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
+
+    ExampleSchema.path('list').discriminator('Text', Schema({
+      data: { type: ObjectId, refPath: 'list.objectType' }
+    }, { _id: false }));
+    ExampleSchema.path('list').discriminator('ExternalSource', Schema({
+      data: { sourceId: Number }
+    }));
+
+    const Example = db.model('Test', ExampleSchema);
+
+    return co(function*() {
+      yield Example.create({
+        test: 'example',
+        list: [
+          { data: { sourceId: 123 }, objectType: 'ExternalSource' }
+        ]
+      });
+
+      const res = yield Example.find().populate('list.data');
+      assert.deepEqual(res[0].toObject().list[0].data, { sourceId: 123 });
+    });
+  });
 });

From 989bff5ce6a26fc666d8a62e8f0d3bdcf652f598 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 12 Feb 2020 13:12:24 -0500
Subject: [PATCH 0486/2348] fix(populate): handle populating when some embedded
 discriminator schemas have `refPath` but none of the subdocs have `refPath`

Fix #8553
---
 lib/document.js                                 |  2 +-
 lib/helpers/populate/getModelsMapForPopulate.js | 10 ++++++++--
 lib/helpers/populate/getSchemaTypes.js          |  6 +++---
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index c1cc10dda23..3fbd83a1d71 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -558,7 +558,7 @@ function markArraySubdocsPopulated(doc, populated) {
       }
       if (val.isMongooseDocumentArray) {
         for (let j = 0; j < val.length; ++j) {
-          val[j].populated(rest, item._docs[id][j], item);
+          val[j].populated(rest, item._docs[id] == null ? [] : item._docs[id][j], item);
         }
         break;
       }
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index b7b5982cdf0..3688c82dc7f 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -34,6 +34,10 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
   let isVirtual = false;
   const modelSchema = model.schema;
 
+  let allSchemaTypes = getSchemaTypes(modelSchema, null, options.path);
+  allSchemaTypes = Array.isArray(allSchemaTypes) ? allSchemaTypes : [allSchemaTypes].filter(v => v != null);
+  const _firstWithRefPath = allSchemaTypes.find(schematype => schematype.options.refPath != null);
+
   for (i = 0; i < len; i++) {
     doc = docs[i];
 
@@ -45,8 +49,9 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     }
 
     modelNames = null;
-    let isRefPath = false;
-    let normalizedRefPath = null;
+    let isRefPath = !!_firstWithRefPath;
+    let normalizedRefPath = _firstWithRefPath ? _firstWithRefPath.options.refPath : null;
+
     if (Array.isArray(schema)) {
       for (let j = 0; j < schema.length; ++j) {
         let _modelNames;
@@ -373,6 +378,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
       let ref;
       let refPath;
+
       if ((ref = get(schemaForCurrentDoc, 'options.ref')) != null) {
         ref = handleRefFunction(ref, doc);
         modelNames = [ref];
diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index e4a3e20950c..8db0079edbf 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -45,14 +45,14 @@ module.exports = function getSchemaTypes(schema, doc, path) {
         }
 
         let schemas = null;
-        if (doc != null && foundschema.schema != null && foundschema.schema.discriminators != null) {
+        if (foundschema.schema != null && foundschema.schema.discriminators != null) {
           const discriminators = foundschema.schema.discriminators;
           const discriminatorKeyPath = trypath + '.' +
             foundschema.schema.options.discriminatorKey;
           const keys = subdoc ? mpath.get(discriminatorKeyPath, subdoc) || [] : [];
           schemas = Object.keys(discriminators).
             reduce(function(cur, discriminator) {
-              if (keys.indexOf(discriminator) !== -1) {
+              if (doc == null || keys.indexOf(discriminator) !== -1) {
                 cur.push(discriminators[discriminator]);
               }
               return cur;
@@ -139,7 +139,7 @@ module.exports = function getSchemaTypes(schema, doc, path) {
       }
 
       const fullPath = nestedPath.concat([trypath]).join('.');
-      if (topLevelDoc.$__ && topLevelDoc.populated(fullPath) && p < parts.length) {
+      if (topLevelDoc != null && topLevelDoc.$__ && topLevelDoc.populated(fullPath) && p < parts.length) {
         const model = doc.$__.populated[fullPath].options[populateModelSymbol];
         if (model != null) {
           const ret = search(

From ca52ead5ba9e80bd38e2a459085c06fce7413174 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 12 Feb 2020 17:50:59 -0500
Subject: [PATCH 0487/2348] chore: release 5.8.12

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 5989bf1c532..3b2176de45e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.8.12 / 2020-02-12
+===================
+ * fix(query): correctly cast dbref `$id` with `$elemMatch` #8577
+ * fix(populate): handle populating when some embedded discriminator schemas have `refPath` but none of the subdocs have `refPath` #8553
+ * docs: add useUnifiedTopology to homepage example #8558 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * refactor(utils): moving promiseOrCallback to helpers/promiseOrCallback #8573 [hugosenari](https://github.com/hugosenari)
+
 5.8.11 / 2020-01-31
 ===================
  * fix(document): allow calling `validate()` multiple times in parallel on subdocs to avoid errors if Mongoose double-validates [taxilian](https://github.com/taxilian) #8548 #8539
diff --git a/package.json b/package.json
index 193a81caabb..209d4837653 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.11",
+  "version": "5.8.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From ff41b74eab2e70f1d229c749f236994d64e0c1cd Mon Sep 17 00:00:00 2001
From: Hugo Ribeiro <hugo.ribeiro@net.com.br>
Date: Wed, 12 Feb 2020 21:03:13 -0300
Subject: [PATCH 0488/2348] refactor(utils): moving clone to helpers/clone

Since clone has some dependencies from utils, also:
- specialProperties to helpers/specialProperties;
- isMongooseObject to helpers/isMongooseObject;
- getFunctionName to helpers/getFunctionName;
- isBsonType to helpers/isBsonType;
- isObject to helpers/isObject.

I'd resisted to temptation to refactor methods, with two exception:
- util.object.vals changed by Object.values;
- utils.each changed forEach.

Updated reference from utils to helpers at:
- lib/browserDocument.js;
- lib/cast.js;
- lib/drivers/node-mongodb-native/collection.js;
- lib/helpers/common.js;
- lib/helpers/schema/getIndexes.js;
- lib/options/PopulateOptions.js;
- lib/options/SchemaTypeOptions.js;
- lib/options/removeOptions.js;
- lib/options/saveOptions.js;
- lib/queryhelpers.js;
- lib/schema/mixed.js;
- lib/types/map.js.
---
 lib/browserDocument.js                        |  18 +-
 lib/cast.js                                   |  15 +-
 lib/drivers/node-mongodb-native/collection.js |   3 +-
 lib/helpers/clone.js                          | 135 +++++++++
 lib/helpers/common.js                         |   6 +-
 lib/helpers/getFunctionName.js                |   8 +
 lib/helpers/isBsonType.js                     |  13 +
 lib/helpers/isMongooseObject.js               |  21 ++
 lib/helpers/isObject.js                       |  16 ++
 lib/helpers/schema/getIndexes.js              |   4 +-
 lib/helpers/specialProperties.js              |   3 +
 lib/options/PopulateOptions.js                |   4 +-
 lib/options/SchemaTypeOptions.js              |   4 +-
 lib/options/removeOptions.js                  |   4 +-
 lib/options/saveOptions.js                    |   4 +-
 lib/queryhelpers.js                           |   8 +-
 lib/schema/mixed.js                           |   4 +-
 lib/types/map.js                              |   4 +-
 lib/utils.js                                  | 198 +------------
 test/helpers/clone.test.js                    | 261 ++++++++++++++++++
 test/helpers/getFunctionName.test.js          |  23 ++
 test/helpers/isBsonType.test.js               |  23 ++
 test/helpers/isMongooseObject.test.js         |  38 +++
 test/helpers/isObject.test.js                 |  54 ++++
 24 files changed, 648 insertions(+), 223 deletions(-)
 create mode 100644 lib/helpers/clone.js
 create mode 100644 lib/helpers/getFunctionName.js
 create mode 100644 lib/helpers/isBsonType.js
 create mode 100644 lib/helpers/isMongooseObject.js
 create mode 100644 lib/helpers/isObject.js
 create mode 100644 lib/helpers/specialProperties.js
 create mode 100644 test/helpers/clone.test.js
 create mode 100644 test/helpers/getFunctionName.test.js
 create mode 100644 test/helpers/isBsonType.test.js
 create mode 100644 test/helpers/isMongooseObject.test.js
 create mode 100644 test/helpers/isObject.test.js

diff --git a/lib/browserDocument.js b/lib/browserDocument.js
index 659470622e9..a44f3077e01 100644
--- a/lib/browserDocument.js
+++ b/lib/browserDocument.js
@@ -11,7 +11,7 @@ const Schema = require('./schema');
 const ObjectId = require('./types/objectid');
 const ValidationError = MongooseError.ValidationError;
 const applyHooks = require('./helpers/model/applyHooks');
-const utils = require('./utils');
+const isObject = require('./helpers/isObject');
 
 /**
  * Document constructor.
@@ -30,7 +30,7 @@ function Document(obj, schema, fields, skipId, skipInit) {
     return new Document(obj, schema, fields, skipId, skipInit);
   }
 
-  if (utils.isObject(schema) && !schema.instanceOfSchema) {
+  if (isObject(schema) && !schema.instanceOfSchema) {
     schema = new Schema(schema);
   }
 
@@ -85,14 +85,12 @@ Document.events = new EventEmitter();
 
 Document.$emitter = new EventEmitter();
 
-utils.each(
-  ['on', 'once', 'emit', 'listeners', 'removeListener', 'setMaxListeners',
-    'removeAllListeners', 'addListener'],
-  function(emitterFn) {
-    Document[emitterFn] = function() {
-      return Document.$emitter[emitterFn].apply(Document.$emitter, arguments);
-    };
-  });
+['on', 'once', 'emit', 'listeners', 'removeListener', 'setMaxListeners',
+  'removeAllListeners', 'addListener'].forEach(function(emitterFn) {
+  Document[emitterFn] = function() {
+    return Document.$emitter[emitterFn].apply(Document.$emitter, arguments);
+  };
+});
 
 /*!
  * Module exports.
diff --git a/lib/cast.js b/lib/cast.js
index da847433e94..9fe01ba7283 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -10,7 +10,8 @@ const castTextSearch = require('./schema/operators/text');
 const get = require('./helpers/get');
 const isOperator = require('./helpers/query/isOperator');
 const util = require('util');
-const utils = require('./utils');
+const isObject = require('./helpers/isObject');
+const isMongooseObject = require('./helpers/isMongooseObject');
 
 const ALLOWED_GEOWITHIN_GEOJSON_TYPES = ['Polygon', 'MultiPolygon'];
 
@@ -139,7 +140,7 @@ module.exports = function cast(schema, obj, options, context) {
           continue;
         }
 
-        if (utils.isObject(val)) {
+        if (isObject(val)) {
           // handle geo schemas that use object notation
           // { loc: { long: Number, lat: Number }
 
@@ -203,7 +204,7 @@ module.exports = function cast(schema, obj, options, context) {
                   context: context
                 });
               }
-              if (utils.isMongooseObject(value.$geometry)) {
+              if (isMongooseObject(value.$geometry)) {
                 value.$geometry = value.$geometry.toObject({
                   transform: false,
                   virtuals: false
@@ -212,7 +213,7 @@ module.exports = function cast(schema, obj, options, context) {
               value = value.$geometry.coordinates;
             } else if (geo === '$geoWithin') {
               if (value.$geometry) {
-                if (utils.isMongooseObject(value.$geometry)) {
+                if (isMongooseObject(value.$geometry)) {
                   value.$geometry = value.$geometry.toObject({ virtuals: false });
                 }
                 const geoWithinType = value.$geometry.type;
@@ -224,7 +225,7 @@ module.exports = function cast(schema, obj, options, context) {
               } else {
                 value = value.$box || value.$polygon || value.$center ||
                   value.$centerSphere;
-                if (utils.isMongooseObject(value)) {
+                if (isMongooseObject(value)) {
                   value = value.toObject({ virtuals: false });
                 }
               }
@@ -325,7 +326,7 @@ module.exports = function cast(schema, obj, options, context) {
 function _cast(val, numbertype, context) {
   if (Array.isArray(val)) {
     val.forEach(function(item, i) {
-      if (Array.isArray(item) || utils.isObject(item)) {
+      if (Array.isArray(item) || isObject(item)) {
         return _cast(item, numbertype, context);
       }
       val[i] = numbertype.castForQueryWrapper({ val: item, context: context });
@@ -336,7 +337,7 @@ function _cast(val, numbertype, context) {
     while (nearLen--) {
       const nkey = nearKeys[nearLen];
       const item = val[nkey];
-      if (Array.isArray(item) || utils.isObject(item)) {
+      if (Array.isArray(item) || isObject(item)) {
         _cast(item, numbertype, context);
         val[nkey] = item;
       } else {
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 71046663d35..bf46a7cb866 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -276,7 +276,8 @@ function format(obj, sub, color) {
     return obj;
   }
 
-  let x = require('../../utils').clone(obj, {transform: false});
+  const clone = require('../../helpers/clone');
+  let x = clone(obj, {transform: false});
 
   if (x.constructor.name === 'Binary') {
     x = 'BinData(' + x.sub_type + ', "' + x.toString('base64') + '")';
diff --git a/lib/helpers/clone.js b/lib/helpers/clone.js
new file mode 100644
index 00000000000..c0ed1364337
--- /dev/null
+++ b/lib/helpers/clone.js
@@ -0,0 +1,135 @@
+'use strict';
+
+
+const cloneRegExp = require('regexp-clone');
+const Decimal = require('../types/decimal128');
+const ObjectId = require('../types/objectid');
+const specialProperties = require('./specialProperties');
+const isMongooseObject = require('./isMongooseObject');
+const getFunctionName = require('./getFunctionName');
+const isBsonType = require('./isBsonType');
+const isObject = require('./isObject');
+const symbols = require('./symbols');
+
+
+/*!
+ * Object clone with Mongoose natives support.
+ *
+ * If options.minimize is true, creates a minimal data object. Empty objects and undefined values will not be cloned. This makes the data payload sent to MongoDB as small as possible.
+ *
+ * Functions are never cloned.
+ *
+ * @param {Object} obj the object to clone
+ * @param {Object} options
+ * @param {Boolean} isArrayChild true if cloning immediately underneath an array. Special case for minimize.
+ * @return {Object} the cloned object
+ * @api private
+ */
+
+function clone(obj, options, isArrayChild) {
+  if (obj == null) {
+    return obj;
+  }
+
+  if (Array.isArray(obj)) {
+    return cloneArray(obj, options);
+  }
+
+  if (isMongooseObject(obj)) {
+    // Single nested subdocs should apply getters later in `applyGetters()`
+    // when calling `toObject()`. See gh-7442, gh-8295
+    if (options && options._skipSingleNestedGetters && obj.$isSingleNested) {
+      options = Object.assign({}, options, { getters: false });
+    }
+    if (options && options.json && typeof obj.toJSON === 'function') {
+      return obj.toJSON(options);
+    }
+    return obj.toObject(options);
+  }
+
+  if (obj.constructor) {
+    switch (getFunctionName(obj.constructor)) {
+      case 'Object':
+        return cloneObject(obj, options, isArrayChild);
+      case 'Date':
+        return new obj.constructor(+obj);
+      case 'RegExp':
+        return cloneRegExp(obj);
+      default:
+        // ignore
+        break;
+    }
+  }
+
+  if (obj instanceof ObjectId) {
+    return new ObjectId(obj.id);
+  }
+
+  if (isBsonType(obj, 'Decimal128')) {
+    if (options && options.flattenDecimals) {
+      return obj.toJSON();
+    }
+    return Decimal.fromString(obj.toString());
+  }
+
+  if (!obj.constructor && isObject(obj)) {
+    // object created with Object.create(null)
+    return cloneObject(obj, options, isArrayChild);
+  }
+
+  if (obj[symbols.schemaTypeSymbol]) {
+    return obj.clone();
+  }
+
+  // If we're cloning this object to go into a MongoDB command,
+  // and there's a `toBSON()` function, assume this object will be
+  // stored as a primitive in MongoDB and doesn't need to be cloned.
+  if (options && options.bson && typeof obj.toBSON === 'function') {
+    return obj;
+  }
+
+  if (obj.valueOf != null) {
+    return obj.valueOf();
+  }
+
+  return cloneObject(obj, options, isArrayChild);
+}
+module.exports = clone;
+
+/*!
+ * ignore
+ */
+
+function cloneObject(obj, options, isArrayChild) {
+  const minimize = options && options.minimize;
+  const ret = {};
+  let hasKeys;
+
+  for (const k in obj) {
+    if (specialProperties.has(k)) {
+      continue;
+    }
+
+    // Don't pass `isArrayChild` down
+    const val = clone(obj[k], options);
+
+    if (!minimize || (typeof val !== 'undefined')) {
+      if (minimize === false && typeof val === 'undefined') {
+        delete ret[k];
+      } else {
+        hasKeys || (hasKeys = true);
+        ret[k] = val;
+      }
+    }
+  }
+
+  return minimize && !isArrayChild ? hasKeys && ret : ret;
+}
+
+function cloneArray(arr, options) {
+  const ret = [];
+  for (let i = 0, l = arr.length; i < l; i++) {
+    ret.push(clone(arr[i], options, true));
+  }
+  return ret;
+}
\ No newline at end of file
diff --git a/lib/helpers/common.js b/lib/helpers/common.js
index 009f481fb12..80f1c4c2a2d 100644
--- a/lib/helpers/common.js
+++ b/lib/helpers/common.js
@@ -6,7 +6,7 @@
 
 const Decimal128 = require('../types/decimal128');
 const ObjectId = require('../types/objectid');
-const utils = require('../utils');
+const isMongooseObject = require('./isMongooseObject');
 
 exports.flatten = flatten;
 exports.modifiedPaths = modifiedPaths;
@@ -17,7 +17,7 @@ exports.modifiedPaths = modifiedPaths;
 
 function flatten(update, path, options, schema) {
   let keys;
-  if (update && utils.isMongooseObject(update) && !Buffer.isBuffer(update)) {
+  if (update && isMongooseObject(update) && !Buffer.isBuffer(update)) {
     keys = Object.keys(update.toObject({ transform: false, virtuals: false }));
   } else {
     keys = Object.keys(update || {});
@@ -78,7 +78,7 @@ function modifiedPaths(update, path, result) {
     let val = update[key];
 
     result[path + key] = true;
-    if (utils.isMongooseObject(val) && !Buffer.isBuffer(val)) {
+    if (isMongooseObject(val) && !Buffer.isBuffer(val)) {
       val = val.toObject({ transform: false, virtuals: false });
     }
     if (shouldFlatten(val)) {
diff --git a/lib/helpers/getFunctionName.js b/lib/helpers/getFunctionName.js
new file mode 100644
index 00000000000..87a2c690ab1
--- /dev/null
+++ b/lib/helpers/getFunctionName.js
@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = function(fn) {
+  if (fn.name) {
+    return fn.name;
+  }
+  return (fn.toString().trim().match(/^function\s*([^\s(]+)/) || [])[1];
+};
diff --git a/lib/helpers/isBsonType.js b/lib/helpers/isBsonType.js
new file mode 100644
index 00000000000..01435d3f285
--- /dev/null
+++ b/lib/helpers/isBsonType.js
@@ -0,0 +1,13 @@
+'use strict';
+
+const get = require('./get');
+
+/*!
+ * Get the bson type, if it exists
+ */
+
+function isBsonType(obj, typename) {
+  return get(obj, '_bsontype', void 0) === typename;
+}
+
+module.exports = isBsonType;
diff --git a/lib/helpers/isMongooseObject.js b/lib/helpers/isMongooseObject.js
new file mode 100644
index 00000000000..016f9e65a86
--- /dev/null
+++ b/lib/helpers/isMongooseObject.js
@@ -0,0 +1,21 @@
+'use strict';
+
+/*!
+ * Returns if `v` is a mongoose object that has a `toObject()` method we can use.
+ *
+ * This is for compatibility with libs like Date.js which do foolish things to Natives.
+ *
+ * @param {any} v
+ * @api private
+ */
+
+module.exports = function(v) {
+  if (v == null) {
+    return false;
+  }
+
+  return v.$__ != null || // Document
+    v.isMongooseArray || // Array or Document Array
+    v.isMongooseBuffer || // Buffer
+    v.$isMongooseMap; // Map
+};
\ No newline at end of file
diff --git a/lib/helpers/isObject.js b/lib/helpers/isObject.js
new file mode 100644
index 00000000000..f8ac31326cb
--- /dev/null
+++ b/lib/helpers/isObject.js
@@ -0,0 +1,16 @@
+'use strict';
+
+/*!
+ * Determines if `arg` is an object.
+ *
+ * @param {Object|Array|String|Function|RegExp|any} arg
+ * @api private
+ * @return {Boolean}
+ */
+
+module.exports = function(arg) {
+  if (Buffer.isBuffer(arg)) {
+    return true;
+  }
+  return Object.prototype.toString.call(arg) === '[object Object]';
+};
\ No newline at end of file
diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index 147fec54592..bb3399966e8 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -1,7 +1,7 @@
 'use strict';
 
 const get = require('../get');
-const utils = require('../../utils');
+const helperIsObject = require('../isObject');
 
 /*!
  * Gather all indexes defined in the schema, including single nested,
@@ -62,7 +62,7 @@ module.exports = function getIndexes(schema) {
 
       if (index !== false && index !== null && index !== undefined) {
         const field = {};
-        const isObject = utils.isObject(index);
+        const isObject = helperIsObject(index);
         const options = isObject ? index : {};
         const type = typeof index === 'string' ? index :
           isObject ? index.type :
diff --git a/lib/helpers/specialProperties.js b/lib/helpers/specialProperties.js
new file mode 100644
index 00000000000..1e1aca50a23
--- /dev/null
+++ b/lib/helpers/specialProperties.js
@@ -0,0 +1,3 @@
+'use strict';
+
+module.exports = new Set(['__proto__', 'constructor', 'prototype']);
\ No newline at end of file
diff --git a/lib/options/PopulateOptions.js b/lib/options/PopulateOptions.js
index 0d3cf266b3b..4a188bd5171 100644
--- a/lib/options/PopulateOptions.js
+++ b/lib/options/PopulateOptions.js
@@ -1,6 +1,6 @@
 'use strict';
 
-const utils = require('../utils');
+const clone = require('../helpers/clone');
 
 class PopulateOptions {
   constructor(obj) {
@@ -9,7 +9,7 @@ class PopulateOptions {
     if (obj == null) {
       return;
     }
-    obj = utils.clone(obj);
+    obj = clone(obj);
     Object.assign(this, obj);
     if (typeof obj.subPopulate === 'object') {
       this.populate = obj.subPopulate;
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 898738d533f..5b00a189189 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -1,6 +1,6 @@
 'use strict';
 
-const utils = require('../utils');
+const clone = require('../helpers/clone');
 
 /**
  * The options defined on a schematype.
@@ -19,7 +19,7 @@ class SchemaTypeOptions {
     if (obj == null) {
       return this;
     }
-    Object.assign(this, utils.clone(obj));
+    Object.assign(this, clone(obj));
   }
 }
 
diff --git a/lib/options/removeOptions.js b/lib/options/removeOptions.js
index 8a91ab7d6e5..0d915864500 100644
--- a/lib/options/removeOptions.js
+++ b/lib/options/removeOptions.js
@@ -1,13 +1,13 @@
 'use strict';
 
-const utils = require('../utils');
+const clone = require('../helpers/clone');
 
 class RemoveOptions {
   constructor(obj) {
     if (obj == null) {
       return;
     }
-    Object.assign(this, utils.clone(obj));
+    Object.assign(this, clone(obj));
   }
 }
 
diff --git a/lib/options/saveOptions.js b/lib/options/saveOptions.js
index 50308deccd7..22ef4375fbe 100644
--- a/lib/options/saveOptions.js
+++ b/lib/options/saveOptions.js
@@ -1,13 +1,13 @@
 'use strict';
 
-const utils = require('../utils');
+const clone = require('../helpers/clone');
 
 class SaveOptions {
   constructor(obj) {
     if (obj == null) {
       return;
     }
-    Object.assign(this, utils.clone(obj));
+    Object.assign(this, clone(obj));
   }
 }
 
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index fc1a5953093..6d78304fbe0 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -10,7 +10,7 @@ const get = require('./helpers/get');
 const getDiscriminatorByValue =
   require('./helpers/discriminator/getDiscriminatorByValue');
 const isDefiningProjection = require('./helpers/projection/isDefiningProjection');
-const utils = require('./utils');
+const clone = require('./helpers/clone');
 
 /*!
  * Prepare a set of path options for query population.
@@ -21,7 +21,7 @@ const utils = require('./utils');
  */
 
 exports.preparePopulationOptions = function preparePopulationOptions(query, options) {
-  const pop = utils.object.vals(query.options.populate);
+  const pop = Object.values(query.options.populate);
 
   // lean options should trickle through all queries
   if (options.lean != null) {
@@ -43,7 +43,7 @@ exports.preparePopulationOptions = function preparePopulationOptions(query, opti
  */
 
 exports.preparePopulationOptionsMQ = function preparePopulationOptionsMQ(query, options) {
-  const pop = utils.object.vals(query._mongooseOptions.populate);
+  const pop = Object.values(query._mongooseOptions.populate);
 
   // lean options should trickle through all queries
   if (options.lean != null) {
@@ -97,7 +97,7 @@ exports.createModel = function createModel(model, doc, fields, userProvidedField
   if (key && value && model.discriminators) {
     const discriminator = model.discriminators[value] || getDiscriminatorByValue(model, value);
     if (discriminator) {
-      const _fields = utils.clone(userProvidedFields);
+      const _fields = clone(userProvidedFields);
       exports.applyPaths(_fields, discriminator.schema);
       return new discriminator(undefined, _fields, true);
     }
diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 672cc519167..d5d5dd1c85f 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -6,7 +6,7 @@
 
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
-const utils = require('../utils');
+const isObject = require('../helpers/isObject');
 
 /**
  * Mixed SchemaType constructor.
@@ -23,7 +23,7 @@ function Mixed(path, options) {
     if (Array.isArray(def) && def.length === 0) {
       // make sure empty array defaults are handled
       options.default = Array;
-    } else if (!options.shared && utils.isObject(def) && Object.keys(def).length === 0) {
+    } else if (!options.shared && isObject(def) && Object.keys(def).length === 0) {
       // prevent odd "shared" objects between documents
       options.default = function() {
         return {};
diff --git a/lib/types/map.js b/lib/types/map.js
index e7cfb4f347d..a188b2f057d 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -3,7 +3,7 @@
 const Mixed = require('../schema/mixed');
 const get = require('../helpers/get');
 const util = require('util');
-const utils = require('../utils');
+const specialProperties = require('../helpers/specialProperties');
 
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
 
@@ -195,7 +195,7 @@ function checkValidKey(key) {
   if (key.includes('.')) {
     throw new Error(`Mongoose maps do not support keys that contain ".", got "${key}"`);
   }
-  if (utils.specialProperties.has(key)) {
+  if (specialProperties.has(key)) {
     throw new Error(`Mongoose maps do not support reserved key name "${key}"`);
   }
 }
diff --git a/lib/utils.js b/lib/utils.js
index 545b00600eb..b0a374982a7 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -4,24 +4,23 @@
  * Module dependencies.
  */
 
+const ms = require('ms');
+const mpath = require('mpath');
+const sliced = require('sliced');
+const Buffer = require('safe-buffer').Buffer;
 const Decimal = require('./types/decimal128');
 const ObjectId = require('./types/objectid');
 const PopulateOptions = require('./options/PopulateOptions');
-const cloneRegExp = require('regexp-clone');
-const get = require('./helpers/get');
+const clone = require('./helpers/clone');
+const isObject = require('./helpers/isObject');
+const isBsonType = require('./helpers/isBsonType');
+const getFunctionName = require('./helpers/getFunctionName');
+const isMongooseObject = require('./helpers/isMongooseObject');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
-const sliced = require('sliced');
-const mpath = require('mpath');
-const ms = require('ms');
-const symbols = require('./helpers/symbols');
-const Buffer = require('safe-buffer').Buffer;
+const specialProperties = require('./helpers/specialProperties');
 
-let MongooseBuffer;
-let MongooseArray;
 let Document;
 
-const specialProperties = new Set(['__proto__', 'constructor', 'prototype']);
-
 exports.specialProperties = specialProperties;
 
 /*!
@@ -148,14 +147,6 @@ exports.deepEqual = function deepEqual(a, b) {
   return true;
 };
 
-/*!
- * Get the bson type, if it exists
- */
-
-function isBsonType(obj, typename) {
-  return get(obj, '_bsontype', void 0) === typename;
-}
-
 /*!
  * Get the last element of an array
  */
@@ -167,88 +158,7 @@ exports.last = function(arr) {
   return void 0;
 };
 
-/*!
- * Object clone with Mongoose natives support.
- *
- * If options.minimize is true, creates a minimal data object. Empty objects and undefined values will not be cloned. This makes the data payload sent to MongoDB as small as possible.
- *
- * Functions are never cloned.
- *
- * @param {Object} obj the object to clone
- * @param {Object} options
- * @param {Boolean} isArrayChild true if cloning immediately underneath an array. Special case for minimize.
- * @return {Object} the cloned object
- * @api private
- */
-
-exports.clone = function clone(obj, options, isArrayChild) {
-  if (obj == null) {
-    return obj;
-  }
-
-  if (Array.isArray(obj)) {
-    return cloneArray(obj, options);
-  }
-
-  if (isMongooseObject(obj)) {
-    // Single nested subdocs should apply getters later in `applyGetters()`
-    // when calling `toObject()`. See gh-7442, gh-8295
-    if (options && options._skipSingleNestedGetters && obj.$isSingleNested) {
-      options = Object.assign({}, options, { getters: false });
-    }
-    if (options && options.json && typeof obj.toJSON === 'function') {
-      return obj.toJSON(options);
-    }
-    return obj.toObject(options);
-  }
-
-  if (obj.constructor) {
-    switch (exports.getFunctionName(obj.constructor)) {
-      case 'Object':
-        return cloneObject(obj, options, isArrayChild);
-      case 'Date':
-        return new obj.constructor(+obj);
-      case 'RegExp':
-        return cloneRegExp(obj);
-      default:
-        // ignore
-        break;
-    }
-  }
-
-  if (obj instanceof ObjectId) {
-    return new ObjectId(obj.id);
-  }
-  if (isBsonType(obj, 'Decimal128')) {
-    if (options && options.flattenDecimals) {
-      return obj.toJSON();
-    }
-    return Decimal.fromString(obj.toString());
-  }
-
-  if (!obj.constructor && exports.isObject(obj)) {
-    // object created with Object.create(null)
-    return cloneObject(obj, options, isArrayChild);
-  }
-
-  if (obj[symbols.schemaTypeSymbol]) {
-    return obj.clone();
-  }
-
-  // If we're cloning this object to go into a MongoDB command,
-  // and there's a `toBSON()` function, assume this object will be
-  // stored as a primitive in MongoDB and doesn't need to be cloned.
-  if (options && options.bson && typeof obj.toBSON === 'function') {
-    return obj;
-  }
-
-  if (obj.valueOf != null) {
-    return obj.valueOf();
-  }
-
-  return cloneObject(obj, options, isArrayChild);
-};
-const clone = exports.clone;
+exports.clone = clone;
 
 /*!
  * ignore
@@ -275,43 +185,6 @@ exports.omit = function omit(obj, keys) {
   return ret;
 };
 
-/*!
- * ignore
- */
-
-function cloneObject(obj, options, isArrayChild) {
-  const minimize = options && options.minimize;
-  const ret = {};
-  let hasKeys;
-
-  for (const k in obj) {
-    if (specialProperties.has(k)) {
-      continue;
-    }
-
-    // Don't pass `isArrayChild` down
-    const val = clone(obj[k], options);
-
-    if (!minimize || (typeof val !== 'undefined')) {
-      if (minimize === false && typeof val === 'undefined') {
-        delete ret[k];
-      } else {
-        hasKeys || (hasKeys = true);
-        ret[k] = val;
-      }
-    }
-  }
-
-  return minimize && !isArrayChild ? hasKeys && ret : ret;
-}
-
-function cloneArray(arr, options) {
-  const ret = [];
-  for (let i = 0, l = arr.length; i < l; i++) {
-    ret.push(clone(arr[i], options, true));
-  }
-  return ret;
-}
 
 /*!
  * Shallow copies defaults into options.
@@ -451,20 +324,7 @@ exports.toObject = function toObject(obj) {
   return obj;
 };
 
-/*!
- * Determines if `arg` is an object.
- *
- * @param {Object|Array|String|Function|RegExp|any} arg
- * @api private
- * @return {Boolean}
- */
-
-exports.isObject = function(arg) {
-  if (Buffer.isBuffer(arg)) {
-    return true;
-  }
-  return Object.prototype.toString.call(arg) === '[object Object]';
-};
+exports.isObject = isObject;
 
 /*!
  * Determines if `arg` is a plain old JavaScript object (POJO). Specifically,
@@ -574,31 +434,7 @@ exports.isMongooseType = function(v) {
   return v instanceof ObjectId || v instanceof Decimal || v instanceof Buffer;
 };
 
-/*!
- * Returns if `v` is a mongoose object that has a `toObject()` method we can use.
- *
- * This is for compatibility with libs like Date.js which do foolish things to Natives.
- *
- * @param {any} v
- * @api private
- */
-
-exports.isMongooseObject = function(v) {
-  Document || (Document = require('./document'));
-  MongooseArray || (MongooseArray = require('./types').Array);
-  MongooseBuffer || (MongooseBuffer = require('./types').Buffer);
-
-  if (v == null) {
-    return false;
-  }
-
-  return v.$__ != null || // Document
-    v.isMongooseArray || // Array or Document Array
-    v.isMongooseBuffer || // Buffer
-    v.$isMongooseMap; // Map
-};
-
-const isMongooseObject = exports.isMongooseObject;
+exports.isMongooseObject = isMongooseObject;
 
 /*!
  * Converts `expires` options of index objects to `expiresAfterSeconds` options for MongoDB.
@@ -949,13 +785,7 @@ exports.buffer.areEqual = function(a, b) {
   return true;
 };
 
-exports.getFunctionName = function(fn) {
-  if (fn.name) {
-    return fn.name;
-  }
-  return (fn.toString().trim().match(/^function\s*([^\s(]+)/) || [])[1];
-};
-
+exports.getFunctionName = getFunctionName;
 /*!
  * Decorate buffers
  */
diff --git a/test/helpers/clone.test.js b/test/helpers/clone.test.js
new file mode 100644
index 00000000000..27a0fac7c51
--- /dev/null
+++ b/test/helpers/clone.test.js
@@ -0,0 +1,261 @@
+'use strict';
+
+const assert = require('assert');
+const clone = require('../../lib/helpers/clone');
+const symbols = require('../../lib/helpers/symbols');
+const ObjectId = require('../../lib/types/objectid');
+const Decimal = require('../../lib/types/decimal128');
+
+describe.only('clone', () => {
+  describe('falsy', () => {
+    it('is null when null', () => {
+      assert.deepStrictEqual(clone(null), null);
+    });
+
+    it('is false when false', () => {
+      assert.deepStrictEqual(clone(false), false);
+    });
+
+    it('is undefined when undefined', () => {
+      assert.deepStrictEqual(clone(undefined), undefined);
+    });
+
+    it('is 0 when 0', () => {
+      assert.deepStrictEqual(clone(0), 0);
+    });
+  });
+
+  describe('Array', () => {
+    it('clones first level', () => {
+      const base = [1, 2];
+      const cloned = clone(base);
+      assert.deepStrictEqual(cloned, base);
+      cloned[0] = 2;
+      assert.deepStrictEqual(base, [1, 2]);
+      assert.deepStrictEqual(cloned, [2, 2]);
+    });
+
+    it('clones deeper', () => {
+      const base = [0, [1], { 2: 2 }];
+      const cloned = clone(base);
+      assert.deepStrictEqual(cloned, base);
+      cloned[0] = 1;
+      cloned[1][0] = 2;
+      cloned[2][2] = 3;
+      assert.deepStrictEqual(cloned, [1, [2], { 2: 3 }]);
+      assert.deepStrictEqual(base, [0, [1], { 2: 2 }]);
+    });
+  });
+
+  describe('mongoose object', () => {
+    it('use toObject', () => {
+      const base = {
+        $__: true,
+        myAttr: 'myAttrVal',
+        toObject() {
+          const obj = JSON.parse(JSON.stringify(base));
+          obj.toObject = base.toObject;
+          return obj;
+        }
+      };
+      const cloned = clone(base);
+      assert.deepStrictEqual(cloned, base);
+      cloned.myAttr = 'otherAttrVal';
+      assert.equal(base.myAttr, 'myAttrVal');
+      assert.equal(cloned.myAttr, 'otherAttrVal');
+    });
+
+    it('use toJSON', () => {
+      const base = {
+        $__: true,
+        myAttr: 'myAttrVal',
+        toJSON: () => JSON.stringify({ $__: true, myAttr: 'myAttrVal' })
+      };
+      const cloned = JSON.parse(clone(base, { json: true }));
+      assert.equal(cloned.myAttr, 'myAttrVal');
+      cloned.myAttr = 'otherAttrVal';
+      assert.equal(base.myAttr, 'myAttrVal');
+      assert.equal(cloned.myAttr, 'otherAttrVal');
+    });
+
+    it('skipSingleNestedGetters', () => {
+      const baseOpts = { _skipSingleNestedGetters: true, $isSingleNested: true };
+      const base = {
+        $__: true,
+        myAttr: 'myAttrVal',
+        $isSingleNested: true,
+        toObject(cloneOpts) {
+          assert.deepStrictEqual(
+            Object.assign({}, baseOpts, { getters: false }),
+            cloneOpts
+          );
+          const obj = JSON.parse(JSON.stringify(base));
+          obj.toObject = base.toObject;
+          return obj;
+        }
+      };
+      const cloned = clone(base, baseOpts);
+      assert.deepStrictEqual(cloned, base);
+      cloned.myAttr = 'otherAttrVal';
+      assert.equal(base.myAttr, 'myAttrVal');
+      assert.equal(cloned.myAttr, 'otherAttrVal');
+    });
+  });
+
+  describe('global objects', () => {
+    describe('constructor is Object', () => {
+      it('!minimize || isArrayChild', () => {
+        const base = { myAttr: 'myAttrVal' };
+        const cloned = clone(base);
+        assert.deepStrictEqual(cloned, base);
+        cloned.myAttr = 'otherAttrVal';
+        assert.equal(base.myAttr, 'myAttrVal');
+        assert.equal(cloned.myAttr, 'otherAttrVal');
+      });
+
+      it('!constructor && !minimize || isArrayChild', () => {
+        const base = Object.create(null);
+        base.myAttr = 'myAttrVal';
+        const cloned = clone(base);
+        assert.equal(base.myAttr, cloned.myAttr);
+        cloned.myAttr = 'otherAttrVal';
+        assert.equal(base.myAttr, 'myAttrVal');
+        assert.equal(cloned.myAttr, 'otherAttrVal');
+      });
+
+      it('minimize && !isArrayChild && hasKey', () => {
+        const base = { myAttr: 'myAttrVal', otherAttr: undefined, prototype: 'p' };
+        const cloned = clone(base, { minimize: true }, true);
+        assert.equal(base.myAttr, cloned.myAttr);
+        assert.deepStrictEqual(Object.keys(base), ['myAttr', 'otherAttr', 'prototype']);
+        assert.deepStrictEqual(Object.keys(cloned), ['myAttr']);
+      });
+
+      it('minimize and !isArrayChild && !hasKey', () => {
+        const base = { otherAttr: undefined, prototype: 'p' };
+        const cloned = clone(base, { minimize: true }, false);
+        assert.equal(cloned, null);
+      });
+    });
+
+    describe('constructor is Data', () => {
+      it('return new equal date ', () => {
+        const base = new Date();
+        const cloned = clone(base);
+        assert.deepStrictEqual(base, cloned);
+      });
+    });
+
+    describe('constructor is RegExp', () => {
+      it('return new equal date ', () => {
+        const base = new RegExp(/A-Z.*/);
+        const cloned = clone(base);
+        assert.deepStrictEqual(base, cloned);
+      });
+    });
+  });
+
+  describe('mongo object', () => {
+    it('is instance of ObjectId', () => {
+      const base = new ObjectId();
+      const cloned = clone(base);
+      assert.deepStrictEqual(base, cloned);
+    });
+  });
+
+  describe('schema type', () => {
+    it('have schemaTypeSymbol property', () => {
+      const base = {
+        myAttr: 'myAttrVal',
+        [symbols.schemaTypeSymbol]: 'MyType',
+        clone() {
+          return {
+            myAttr: this.myAttr,
+          };
+        }
+      };
+      const cloned = clone(base);
+      assert.deepStrictEqual(base.myAttr, cloned.myAttr);
+    });
+  });
+
+  describe('bson', () => {
+    it('Decimal128', () => {
+      const base = {
+        _bsontype: 'Decimal128',
+        toString() { return '128'; }
+      };
+      base.constructor = undefined;
+      const cloned = clone(base);
+      const expected = Decimal.fromString(base.toString());
+      assert.deepStrictEqual(cloned, expected);
+    });
+
+    it('Decimal128 (flatternDecimal)', () => {
+      const base = {
+        _bsontype: 'Decimal128',
+        toJSON() { return 128; }
+      };
+      base.constructor = undefined;
+      const cloned = clone(base, { flattenDecimals: true });
+      assert.deepStrictEqual(cloned, base.toJSON());
+    });
+
+    it('does nothing', () => {
+      class BeeSon {
+        constructor() { this.myAttr = 'myAttrVal'; }
+        toBSON( ) {}
+      }
+      const base = new BeeSon();
+      const cloned = clone(base, { bson: true });
+      assert.equal(base.myAttr, cloned.myAttr);
+      cloned.myAttr = 'otherAttrVal';
+      assert.equal(base.myAttr, 'otherAttrVal');
+      assert.equal(cloned.myAttr, 'otherAttrVal');
+    });
+  });
+
+  describe('wrapper', () => {
+
+  });
+
+  describe('any else', () => {
+    it('valueOf', () => {
+      let called = false;
+      class Wrapper {
+        constructor(myAttr) {
+          this.myAttr = myAttr;
+        }
+        valueOf() {
+          called = true;
+          return new Wrapper(this.myAttr);
+        }
+      }
+      const base = new Wrapper('myAttrVal');
+      const cloned = clone(base);
+      assert.ok(called);
+      assert.deepStrictEqual(cloned, base);
+      cloned.myAttr = 'otherAttrVal';
+      assert.equal(base.myAttr, 'myAttrVal');
+      assert.equal(cloned.myAttr, 'otherAttrVal');
+    });
+
+    it('cloneObject', () => {
+      class CloneMe {
+        constructor(myAttr) {
+          this.myAttr = myAttr;
+        }
+      }
+      const base = new CloneMe('myAttrVal');
+      base.valueOf = undefined;
+      const cloned = clone(base);
+      assert.equal(base.myAttr, cloned.myAttr);
+      cloned.myAttr = 'otherAttrVal';
+      assert.equal(base.myAttr, 'myAttrVal');
+      assert.equal(cloned.myAttr, 'otherAttrVal');
+      // I can't say it's expected behavior, but is how it's behave.
+      assert.equal(typeof cloned, 'object');
+      assert.equal(cloned.constructor, Object);
+    });
+  });
+});
\ No newline at end of file
diff --git a/test/helpers/getFunctionName.test.js b/test/helpers/getFunctionName.test.js
new file mode 100644
index 00000000000..d3b7dbe3bdb
--- /dev/null
+++ b/test/helpers/getFunctionName.test.js
@@ -0,0 +1,23 @@
+'use strict';
+
+const assert = require('assert');
+const getFunctionName = require('../../lib/helpers/getFunctionName');
+
+describe('getFunctionName', () => {
+  it('return fn.name', () => {
+    assert.equal(getFunctionName({ name: 'fnName'}), 'fnName');
+  });
+
+  it('return function name', () => {
+    assert.equal(getFunctionName(function fnName() {}), 'fnName');
+  });
+
+  it('return function functionName', () => {
+    assert.equal(getFunctionName(function functionName() {}), 'functionName');
+  });
+
+  it('return undefined for arrow function', () => {
+    // I can't say it's expected behavior, but is how it's behave.
+    assert.equal(getFunctionName(() => []), undefined);
+  });
+});
\ No newline at end of file
diff --git a/test/helpers/isBsonType.test.js b/test/helpers/isBsonType.test.js
new file mode 100644
index 00000000000..8716bd08c42
--- /dev/null
+++ b/test/helpers/isBsonType.test.js
@@ -0,0 +1,23 @@
+'use strict';
+
+const assert = require('assert');
+const isBsonType = require('../../lib/helpers/isBsonType');
+
+describe('isBsonType', () => {
+  it('true for any object with _bsontype property equal typename', () => {
+    assert.ok(isBsonType({ _bsontype: 'MyType' }, 'MyType'));
+  });
+
+  it('true for any object without _bsontype property and undefined typename', () => {
+    assert.ok(isBsonType({ }));
+  });
+
+  it('false for any object with _bsontype property different of typename', () => {
+    assert.ok(!isBsonType({ _bsontype: 'MyType' }, 'OtherType'));
+  });
+
+  it('false for any object without _bsontype property', () => {
+    // I can't say it's expected behavior, but is how it's behave.
+    assert.ok(!isBsonType({ }, 'OtherType'));
+  });
+});
\ No newline at end of file
diff --git a/test/helpers/isMongooseObject.test.js b/test/helpers/isMongooseObject.test.js
new file mode 100644
index 00000000000..db8babd3af8
--- /dev/null
+++ b/test/helpers/isMongooseObject.test.js
@@ -0,0 +1,38 @@
+'use strict';
+
+const assert = require('assert');
+const isMongooseObject = require('../../lib/helpers/isMongooseObject');
+
+describe('isMongooseObject', () => {
+  it('is when value.$__ != null', () => {
+    assert.ok(isMongooseObject({ $__: !null }));
+  });
+
+  it('is when value.isMongooseArray is truthy', () => {
+    assert.ok(isMongooseObject({ isMongooseArray: true }));
+  });
+
+  it('is when value.isMongooseBuffer is truthy', () => {
+    assert.ok(isMongooseObject({ isMongooseBuffer: true }));
+  });
+
+  it('is when value.$isMongooseMap is truthy', () => {
+    assert.ok(isMongooseObject({ $isMongooseMap: true }));
+  });
+
+  it('is not when anything else', () => {
+    assert.ok(!isMongooseObject(''));
+    assert.ok(!isMongooseObject([]));
+    assert.ok(!isMongooseObject({}));
+    assert.ok(!isMongooseObject(/./));
+    assert.ok(!isMongooseObject(null));
+    assert.ok(!isMongooseObject(false));
+    assert.ok(!isMongooseObject(undefined));
+    assert.ok(!isMongooseObject(new Array));
+    assert.ok(!isMongooseObject(new Function));
+    assert.ok(!isMongooseObject(new Object));
+    assert.ok(!isMongooseObject(new RegExp));
+    assert.ok(!isMongooseObject(new String));
+    assert.ok(!isMongooseObject(Buffer.from([])));
+  });
+});
\ No newline at end of file
diff --git a/test/helpers/isObject.test.js b/test/helpers/isObject.test.js
new file mode 100644
index 00000000000..6ec0f1e447b
--- /dev/null
+++ b/test/helpers/isObject.test.js
@@ -0,0 +1,54 @@
+'use strict';
+
+const assert = require('assert');
+const isObject = require('../../lib/helpers/isObject');
+
+describe('isObject', () => {
+  describe('true for', () => {
+    it('{}', () => {
+      assert.ok(isObject({}));
+    });
+
+    it('Buffer', () => {
+      assert.ok(isObject(Buffer.from([])));
+    });
+
+    it('Object', () => {
+      assert.ok(isObject(new Object));
+    });
+  });
+
+  describe('false for', () => {
+    it('""', () => {
+      assert.ok(!isObject(''));
+    });
+
+    it('/.*/', () => {
+      assert.ok(!isObject(/.*/));
+    });
+
+    it('[]', () => {
+      assert.ok(!isObject([]));
+    });
+
+    it('Array', () => {
+      assert.ok(!isObject(new Array));
+    });
+
+    it('Function', () => {
+      assert.ok(!isObject(new Function));
+    });
+
+    it('RegExp', () => {
+      assert.ok(!isObject(new RegExp));
+    });
+
+    it('String', () => {
+      assert.ok(!isObject(new String));
+    });
+
+    it('"[object Object]"', () => {
+      assert.ok(!isObject('[object Object]'));
+    });
+  });
+});

From 18ea0a8a0878dbed452dba91576a31fde31dde54 Mon Sep 17 00:00:00 2001
From: Hugo Ribeiro <hugo.ribeiro@net.com.br>
Date: Wed, 12 Feb 2020 21:41:56 -0300
Subject: [PATCH 0489/2348] style(tests) remove comment

---
 test/helpers/isBsonType.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/helpers/isBsonType.test.js b/test/helpers/isBsonType.test.js
index 8716bd08c42..54396787926 100644
--- a/test/helpers/isBsonType.test.js
+++ b/test/helpers/isBsonType.test.js
@@ -17,7 +17,6 @@ describe('isBsonType', () => {
   });
 
   it('false for any object without _bsontype property', () => {
-    // I can't say it's expected behavior, but is how it's behave.
     assert.ok(!isBsonType({ }, 'OtherType'));
   });
 });
\ No newline at end of file

From 55a34648cb9c7bcee7442f0feaa7b5be5aecadc0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Feb 2020 11:02:28 -0500
Subject: [PATCH 0490/2348] fix(populate): use safe get to avoid crash if
 schematype doesn't have options

Re: #8586
---
 lib/helpers/populate/getModelsMapForPopulate.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 3688c82dc7f..16b3b664991 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -36,7 +36,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
   let allSchemaTypes = getSchemaTypes(modelSchema, null, options.path);
   allSchemaTypes = Array.isArray(allSchemaTypes) ? allSchemaTypes : [allSchemaTypes].filter(v => v != null);
-  const _firstWithRefPath = allSchemaTypes.find(schematype => schematype.options.refPath != null);
+  const _firstWithRefPath = allSchemaTypes.find(schematype => get(schematype, 'options.refPath', null) != null);
 
   for (i = 0; i < len; i++) {
     doc = docs[i];
@@ -50,7 +50,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
     modelNames = null;
     let isRefPath = !!_firstWithRefPath;
-    let normalizedRefPath = _firstWithRefPath ? _firstWithRefPath.options.refPath : null;
+    let normalizedRefPath = _firstWithRefPath ? get(_firstWithRefPath, 'options.refPath', null) : null;
 
     if (Array.isArray(schema)) {
       for (let j = 0; j < schema.length; ++j) {

From 849afd2e34f653c4dcf0a76821f025fe581bf1eb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Feb 2020 11:06:01 -0500
Subject: [PATCH 0491/2348] chore: release 5.8.13

---
 History.md   | 4 ++++
 package.json | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 3b2176de45e..9feb43b180a 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,7 @@
+5.8.13 / 2020-02-13
+===================
+ * fix(populate): use safe get to avoid crash if schematype doesn't have options #8586
+
 5.8.12 / 2020-02-12
 ===================
  * fix(query): correctly cast dbref `$id` with `$elemMatch` #8577
diff --git a/package.json b/package.json
index 209d4837653..01c6b6eb7a5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.12",
+  "version": "5.8.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From f6c2da4f2cd12acd4eda7cd586119db88c122281 Mon Sep 17 00:00:00 2001
From: sam-mfb <sam@mfbtech.com>
Date: Thu, 13 Feb 2020 11:22:41 -0500
Subject: [PATCH 0492/2348] fix: update documentation of custom _id overriding
 in discriminators

---
 test/docs/discriminators.test.js | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index 76ced02bd1a..a0f210cf64f 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -186,15 +186,14 @@ describe('discriminator docs', function () {
   /**
    * A discriminator's fields are the union of the base schema's fields and
    * the discriminator schema's fields, and the discriminator schema's fields
-   * take precedence. There is one exception: the default `_id` field.
-   *
-   * You can work around this by setting the `_id` option to false in the
-   * discriminator schema as shown below.
+   * take precedence. There is one exception: the `_id` field.
+   * If a custom _id field is set on the base schema, that will always
+   * override the discriminator's _id field, as shown below.
    */
   it('Handling custom _id fields', function (done) {
     var options = {discriminatorKey: 'kind'};
 
-    // Base schema has a String `_id` and a Date `time`...
+    // Base schema has a custom String `_id` and a Date `time`...
     var eventSchema = new mongoose.Schema({_id: String, time: Date},
       options);
     var Event = mongoose.model('BaseEvent', eventSchema);
@@ -203,16 +202,16 @@ describe('discriminator docs', function () {
       url: String,
       time: String
     }, options);
-    // But the discriminator schema has a String `time`, and an implicitly added
-    // ObjectId `_id`.
+    // The discriminator schema has a String `time` and an
+    // implicitly added ObjectId `_id`.
     assert.ok(clickedLinkSchema.path('_id'));
     assert.equal(clickedLinkSchema.path('_id').instance, 'ObjectID');
     var ClickedLinkEvent = Event.discriminator('ChildEventBad',
       clickedLinkSchema);
 
-    var event1 = new ClickedLinkEvent({ _id: 'custom id', time: '4pm' });
-    // Woops, clickedLinkSchema overwrites the `time` path, but **not**
-    // the `_id` path because that was implicitly added.
+    var event1 = new ClickedLinkEvent({_id: 'custom id', time: '4pm'});
+    // clickedLinkSchema overwrites the `time` path, but **not**
+    // the `_id` path.
     assert.strictEqual(typeof event1._id, 'string');
     assert.strictEqual(typeof event1.time, 'string');
 

From 0bf6afc687f88108fe23618c19ea13b573474705 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Feb 2020 13:36:01 -0500
Subject: [PATCH 0493/2348] chore: upgrade mongodb driver -> 3.5.3

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 22a2ea2bf73..8c44fec0cf1 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.5.1",
+    "mongodb": "3.5.3",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From 34eef3483540deeb59d3ab36d028960fd7ae69d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Feb 2020 15:18:02 -0500
Subject: [PATCH 0494/2348] chore: release 5.9.0

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9feb43b180a..3ced12cb3ee 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.9.0 / 2020-02-13
+==================
+ * fix: upgrade to MongoDB driver 3.5 #8520 #8563
+ * feat(schematype): support setting default options for schema type (`trim` on all strings, etc.) #8487
+ * feat(populate): add `perDocumentLimit` option that limits per document in `find()` result, rather than across all documents #7318
+ * feat(schematype): enable setting `transform` option on individual schematypes #8403
+ * feat(timestamps): allow setting `currentTime` option for setting custom function to get the current time #3957
+ * feat(connection): add `Connection#watch()` to watch for changes on an entire database #8425
+ * feat(document): add `Document#$op` property to make it easier to tell what operation is running in middleware #8439
+ * feat(populate): support `limit` as top-level populate option #8445
+
 5.8.13 / 2020-02-13
 ===================
  * fix(populate): use safe get to avoid crash if schematype doesn't have options #8586
diff --git a/package.json b/package.json
index 8c44fec0cf1..401cb42803a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.8.13",
+  "version": "5.9.0",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From bb979b361463d3386a689506b6154145774982a8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Feb 2020 18:12:12 -0500
Subject: [PATCH 0495/2348] test(document): repro #8583

---
 test/document.test.js | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 57ef389a982..6ff443df867 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8693,6 +8693,36 @@ describe('document', function() {
     });
     assert.equal(doc.toObject({ transform: true }).myDate, '2015');
     assert.equal(doc.toObject({ transform: true }).dates[0], '2016');
-    //assert.equal(doc.toObject({ transform: true }).arr[0].myDate, '2017');
+    assert.equal(doc.toObject({ transform: true }).arr[0].myDate, '2017');
+  });
+
+  it('handles setting numeric paths with single nested subdocs (gh-8583)', function() {
+    const placedItemSchema = Schema({ image: String }, { _id: false });
+    
+    const subdocumentSchema = Schema({
+      placedItems: {
+        '1': placedItemSchema,
+        first: placedItemSchema
+      }
+    });
+    const Model = db.model('Test', subdocumentSchema);
+
+    return co(function*() {
+      const doc = yield Model.create({
+        placedItems: { '1': { image: 'original' }, first: { image: 'original' } }
+      });
+
+      doc.set({
+        'placedItems.1.image': 'updated',
+        'placedItems.first.image': 'updated'
+      });
+
+      yield doc.save();
+
+      assert.equal(doc.placedItems['1'].image, 'updated');
+
+      const fromDb = yield Model.findById(doc);
+      assert.equal(fromDb.placedItems['1'].image, 'updated');
+    });
   });
 });

From db49e96f4092862b833283eb55f6f9a6ce9c4eb7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Feb 2020 18:12:40 -0500
Subject: [PATCH 0496/2348] fix(schema): return correct pathType when single
 nested path is embedded under a nested path with a numeric name

Fix #8583
---
 lib/schema.js              | 4 ++--
 test/helpers/clone.test.js | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 328995731c2..312aa6cd85c 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1098,10 +1098,10 @@ Schema.prototype.pathType = function(path) {
   if (this.nested.hasOwnProperty(path)) {
     return 'nested';
   }
-  if (this.subpaths.hasOwnProperty(cleanPath)) {
+  if (this.subpaths.hasOwnProperty(cleanPath) || this.subpaths.hasOwnProperty(path)) {
     return 'real';
   }
-  if (this.singleNestedPaths.hasOwnProperty(cleanPath)) {
+  if (this.singleNestedPaths.hasOwnProperty(cleanPath) || this.singleNestedPaths.hasOwnProperty(path)) {
     return 'real';
   }
 
diff --git a/test/helpers/clone.test.js b/test/helpers/clone.test.js
index 27a0fac7c51..4e1590c5ba4 100644
--- a/test/helpers/clone.test.js
+++ b/test/helpers/clone.test.js
@@ -6,7 +6,7 @@ const symbols = require('../../lib/helpers/symbols');
 const ObjectId = require('../../lib/types/objectid');
 const Decimal = require('../../lib/types/decimal128');
 
-describe.only('clone', () => {
+describe('clone', () => {
   describe('falsy', () => {
     it('is null when null', () => {
       assert.deepStrictEqual(clone(null), null);

From a1b83088f1ed287ea98348feb180c5c57080c4f5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 09:51:18 -0500
Subject: [PATCH 0497/2348] style: fix lint

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 6ff443df867..f961eed0be0 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8698,7 +8698,7 @@ describe('document', function() {
 
   it('handles setting numeric paths with single nested subdocs (gh-8583)', function() {
     const placedItemSchema = Schema({ image: String }, { _id: false });
-    
+
     const subdocumentSchema = Schema({
       placedItems: {
         '1': placedItemSchema,

From d57c84b1ba3d420edb0d22f61e2758e7df3b6b0f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 09:57:57 -0500
Subject: [PATCH 0498/2348] fix(queryhelpers): remove `Object.values()` for
 Node.js 4.x-6.x support

Re: #8596
---
 lib/queryhelpers.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 6d78304fbe0..343c3b175c4 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -21,7 +21,8 @@ const clone = require('./helpers/clone');
  */
 
 exports.preparePopulationOptions = function preparePopulationOptions(query, options) {
-  const pop = Object.values(query.options.populate);
+  const _populate = query.options.populate;
+  const pop = Object.keys(_populate).reduce((vals, key) => vals.concat([_populate[key]]), []);
 
   // lean options should trickle through all queries
   if (options.lean != null) {
@@ -43,7 +44,8 @@ exports.preparePopulationOptions = function preparePopulationOptions(query, opti
  */
 
 exports.preparePopulationOptionsMQ = function preparePopulationOptionsMQ(query, options) {
-  const pop = Object.values(query._mongooseOptions.populate);
+  const _populate = query._mongooseOptions.populate;
+  const pop = Object.keys(_populate).reduce((vals, key) => vals.concat([_populate[key]]), []);
 
   // lean options should trickle through all queries
   if (options.lean != null) {

From 9aa46a61dfd6490ca504221320af2249495eef38 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 10:13:14 -0500
Subject: [PATCH 0499/2348] fix: use eslint to check for mocha only() until we
 can drop node 4 support

Fix #8596
---
 package.json | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/package.json b/package.json
index 401cb42803a..587332f420d 100644
--- a/package.json
+++ b/package.json
@@ -46,6 +46,7 @@
     "co": "4.6.0",
     "dox": "0.3.1",
     "eslint": "5.16.0",
+    "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.1.0",
     "lodash.isequal": "4.5.0",
     "lodash.isequalwith": "4.4.0",
@@ -102,6 +103,9 @@
     "extends": [
       "eslint:recommended"
     ],
+    "plugins": [
+      "mocha-no-only"
+    ],
     "parserOptions": {
       "ecmaVersion": 2015
     },
@@ -150,6 +154,9 @@
           "name": "context",
           "message": "Don't use Mocha's global context"
         }
+      ],
+      "mocha-no-only/mocha-no-only": [
+        "error"
       ]
     }
   },

From 636be986d467b2d48f86dd9a75f6bc97bc1f4fd3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 11:15:18 -0500
Subject: [PATCH 0500/2348] test(cursor): repro #8557

---
 test/query.cursor.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 83b0a48984a..7d4da6b2bcd 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -506,4 +506,22 @@ describe('QueryCursor', function() {
       assert.equal(numDone, 3);
     });
   });
+
+  it('eachAsync() with sort, parallel, and sync function (gh-8557)', function() {
+    const User = db.model('User', Schema({ order: Number }));
+
+    return co(function*() {
+      yield User.create([{ order: 1 }, { order: 2 }, { order: 3 }]);
+
+      const cursor = User.aggregate([{ $sort: { order: 1 } }]).
+        cursor().
+        exec();
+
+      const docs = [];
+
+      yield cursor.eachAsync((doc) => docs.push(doc), { parallel: 3 });
+
+      assert.deepEqual(docs.map(d => d.order), [1, 2, 3]);
+    });
+  });
 });

From 8bd4ea2010d21f704f7494234815422d63df4387 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 11:15:32 -0500
Subject: [PATCH 0501/2348] fix(cursor): respect sort order when using
 `eachAsync()` with `parallel` and a sync callback

Fix #8557
---
 lib/helpers/cursor/eachAsync.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index c50d02af34a..cd99280fc93 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -70,7 +70,7 @@ module.exports = function eachAsync(next, fn, options, callback) {
 
         // Kick off the subsequent `next()` before handling the result, but
         // make sure we know that we still have a result to handle re: #8422
-        done();
+        process.nextTick(() => done());
 
         handleNextResult(doc, function(err) {
           --handleResultsInProgress;
@@ -117,4 +117,4 @@ function asyncQueue() {
       fn(_step);
     }
   }
-}
\ No newline at end of file
+}

From 659f2a5546e407773a6ca8e8da2b5d754f856753 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 16:03:46 -0500
Subject: [PATCH 0502/2348] test(model): repro #8571

---
 test/docs/transactions.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index 8b810542ced..5ad59cc6deb 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -343,4 +343,17 @@ describe('transactions', function() {
       assert.deepEqual(fromDb, { name: 'Tyrion Lannister' });
     });
   });
+
+  it('save() with no changes (gh-8571)', function() {
+    return co(function*() {
+      const Test = db.model('Test', Schema({ name: String }));
+
+      yield Test.createCollection();
+      const session = yield db.startSession();
+      yield session.withTransaction(() => co(function*() {
+        const [test] = yield Test.create([{}], { session });
+        yield test.save(); // throws DocumentNotFoundError
+      }));
+    });
+  });
 });

From 15b7f05f6c3b3207f75cb5c73cf01e95f78cf04c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 16:06:25 -0500
Subject: [PATCH 0503/2348] fix(model): set session when calling `save()` with
 no changes

Fix #8571
---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index e7ab67e909b..1a9020e38a9 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -313,7 +313,7 @@ Model.prototype.$__handleSave = function(options, callback) {
         callback(null, ret);
       });
     } else {
-      this.constructor.exists(this.$__where())
+      this.constructor.exists(this.$__where(), saveOptions)
         .then((documentExists)=>{
           if (!documentExists) throw new DocumentNotFoundError(this.$__where(),this.constructor.modelName);
 

From 5061e942abf5b37a2a1019675502d62608cf60b7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 16:10:44 -0500
Subject: [PATCH 0504/2348] test: fix tests re: #8571

---
 test/docs/transactions.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index 5ad59cc6deb..95e0aa4f589 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -351,7 +351,7 @@ describe('transactions', function() {
       yield Test.createCollection();
       const session = yield db.startSession();
       yield session.withTransaction(() => co(function*() {
-        const [test] = yield Test.create([{}], { session });
+        const test = yield Test.create([{}], { session }).then(res => res[0]);
         yield test.save(); // throws DocumentNotFoundError
       }));
     });

From 427633d35b7dcf4b007cc0e8d850318845c08f69 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Feb 2020 17:26:08 -0500
Subject: [PATCH 0505/2348] chore: release 5.9.1

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 3ced12cb3ee..2581448138f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.9.1 / 2020-02-14
+==================
+ * fix(model): set session when calling `save()` with no changes #8571
+ * fix(schema): return correct pathType when single nested path is embedded under a nested path with a numeric name #8583
+ * fix(queryhelpers): remove `Object.values()` for Node.js 4.x-6.x support #8596
+ * fix(cursor): respect sort order when using `eachAsync()` with `parallel` and a sync callback #8577
+ * docs: update documentation of custom _id overriding in discriminators #8591 [sam-mfb](https://github.com/sam-mfb)
+
 5.9.0 / 2020-02-13
 ==================
  * fix: upgrade to MongoDB driver 3.5 #8520 #8563
diff --git a/package.json b/package.json
index 587332f420d..39ebfbdbc3d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.0",
+  "version": "5.9.1",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 25eee9648c6054be1a826eeb6dba901f441cb116 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 10:02:02 -0500
Subject: [PATCH 0506/2348] test(update): repro #8580

---
 test/model.update.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 8a767e91be6..11688e0ddb4 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3330,6 +3330,21 @@ describe('model: updateOne: ', function() {
     });
   });
 
+  it('updates buffers with `runValidators` successfully (gh-8580)', function() {
+    const Test = db.model('Test', Schema({
+      data: { type: Buffer, required: true }
+    }));
+
+    const opts = { runValidators: true, upsert: true };
+    return co(function*() {
+      yield Test.updateOne({}, { data: Buffer.from('test') }, opts);
+
+      const doc = yield Test.findOne();
+      assert.ok(doc.data);
+      assert.equal(doc.data.toString('utf8'), 'test');
+    });
+  });
+
   describe('mongodb 42 features', function() {
     before(function(done) {
       start.mongodVersion((err, version) => {

From 255432dd3cddbe158081b7211ba238a49f376299 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 10:02:14 -0500
Subject: [PATCH 0507/2348] fix(update): handle Binary type correctly qwith
 `runValidators`

Fix #8580
---
 lib/helpers/common.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/common.js b/lib/helpers/common.js
index 80f1c4c2a2d..ed7dc42c1d7 100644
--- a/lib/helpers/common.js
+++ b/lib/helpers/common.js
@@ -4,6 +4,7 @@
  * Module dependencies.
  */
 
+const Binary = require('../driver').get().Binary;
 const Decimal128 = require('../types/decimal128');
 const ObjectId = require('../types/objectid');
 const isMongooseObject = require('./isMongooseObject');
@@ -100,5 +101,6 @@ function shouldFlatten(val) {
     !(val instanceof ObjectId) &&
     (!Array.isArray(val) || val.length > 0) &&
     !(val instanceof Buffer) &&
-    !(val instanceof Decimal128);
+    !(val instanceof Decimal128) &&
+    !(val instanceof Binary);
 }

From dd01335ef7a3e6b3ff3cadf78d32fab02e9e0605 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 12:39:04 -0500
Subject: [PATCH 0508/2348] docs(connections): add description of how to handle
 `bufferCommands: false` with capped collections

Re: #8566
---
 docs/connections.pug | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/docs/connections.pug b/docs/connections.pug
index dd9375cc7e7..79cc2468eb8 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -88,6 +88,28 @@ block content
     mongoose.set('bufferCommands', false);
     ```
 
+    Note that buffering is also responsible for waiting until Mongoose
+    creates collections if you use the [`autoCreate` option](/docs/guide.html#autoCreate).
+    If you disable buffering, you should also disable the `autoCreate`
+    option and use [`createCollection()`](/docs/api/model.html#model_Model.createCollection)
+    to create [capped collections](/docs/guide.html#capped) or
+    [collections with collations](/docs/guide.html#collation).
+
+    ```javascript
+    const schema = new Schema({
+      name: String
+    }, {
+      capped: { size: 1024 },
+      bufferCommands: false,
+      autoCreate: false // disable `autoCreate` since `bufferCommands` is false
+    });
+
+    const Model = mongoose.model('Test', schema);
+    // Explicitly create the collection before using it
+    // so the collection is capped.
+    await Model.createCollection();
+    ```
+
     <h3 id="error-handling"><a href="#error-handling">Error Handling</a></h3>
 
     There are two classes of errors that can occur with a Mongoose connection.

From 447936bfc9bddf3c3c9ba40e3fc7886e7a1ab0a7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 12:40:14 -0500
Subject: [PATCH 0509/2348] fix(collection): skip creating capped collection if
 `autoCreate` set to `false`

Fix #8566
---
 lib/drivers/node-mongodb-native/collection.js |  5 ++++
 lib/model.js                                  |  1 +
 test/collection.capped.test.js                | 26 +++++++++++++++++++
 3 files changed, 32 insertions(+)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index bf46a7cb866..380e0f1c567 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -51,6 +51,11 @@ NativeCollection.prototype.onOpen = function() {
     return _this.collection;
   }
 
+  if (_this.opts.autoCreate === false) {
+    _this.collection = _this.conn.db.collection(_this.name);
+    return _this.collection;
+  }
+
   // capped
   return _this.conn.db.collection(_this.name, function(err, c) {
     if (err) return callback(err);
diff --git a/lib/model.js b/lib/model.js
index 1a9020e38a9..dfd9e0a6251 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4700,6 +4700,7 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
   const collectionOptions = {
     bufferCommands: bufferCommands,
     capped: schema.options.capped,
+    autoCreate: schema.options.autoCreate,
     Promise: model.base.Promise
   };
 
diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index 1a2ad1d7219..35107b105f5 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -7,6 +7,7 @@
 const start = require('./common');
 
 const assert = require('assert');
+const co = require('co');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
@@ -92,4 +93,29 @@ describe('collections: capped:', function() {
       });
     });
   });
+
+  it('skips when setting autoCreate to false (gh-8566)', function() {
+    const db = start();
+    this.timeout(30000);
+
+    return co(function*() {
+      yield db.dropDatabase();
+
+      const schema = new mongoose.Schema({
+        name: String
+      }, {
+        capped: { size: 1024 },
+        bufferCommands: false,
+        autoCreate: false // disable `autoCreate` since `bufferCommands` is false
+      });
+
+      const Model = db.model('Test', schema);
+      // Explicitly create the collection before using it
+      // so the collection is capped.
+      yield Model.createCollection({ capped: true, size: 1024 });
+
+      // Should not throw
+      yield Model.create({ name: 'test' });
+    });
+  });
 });

From 2789a3dbbe47892832525ab1075d29646c7ec147 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 12:44:45 -0500
Subject: [PATCH 0510/2348] test: clean up test failures for #8566

---
 test/collection.capped.test.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index 35107b105f5..e24f4893f46 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -35,6 +35,10 @@ describe('collections: capped:', function() {
     db.close(done);
   });
 
+  afterEach(function() {
+    return db.dropDatabase();
+  });
+
   it('schemas should have option size', function(done) {
     assert.ok(capped.options.capped);
     assert.equal(capped.options.capped.size, 1000);

From 3cfa125f8ab075a8200c50be0e1cc76f963705ca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 12:49:08 -0500
Subject: [PATCH 0511/2348] test: more test fixes

---
 test/collection.capped.test.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index e24f4893f46..5c530ebf108 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -31,14 +31,14 @@ describe('collections: capped:', function() {
     db = start();
   });
 
-  after(function(done) {
-    db.close(done);
-  });
-
   afterEach(function() {
     return db.dropDatabase();
   });
 
+  after(function(done) {
+    db.close(done);
+  });
+
   it('schemas should have option size', function(done) {
     assert.ok(capped.options.capped);
     assert.equal(capped.options.capped.size, 1000);

From c2231e237c36a2979a4502b2bede8f6e15238027 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 12:52:49 -0500
Subject: [PATCH 0512/2348] test: more test fixes for #8566

---
 test/collection.capped.test.js | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index 5c530ebf108..cac4eedfeea 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -31,10 +31,6 @@ describe('collections: capped:', function() {
     db = start();
   });
 
-  afterEach(function() {
-    return db.dropDatabase();
-  });
-
   after(function(done) {
     db.close(done);
   });
@@ -120,6 +116,8 @@ describe('collections: capped:', function() {
 
       // Should not throw
       yield Model.create({ name: 'test' });
+
+      yield db.dropDatabase();
     });
   });
 });

From 53e8bd11a39dbb28ceaebc54ae1795b3b57d9b41 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 13:19:42 -0500
Subject: [PATCH 0513/2348] test(query): repro #8555

---
 test/query.middleware.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index dd3d0cab9ed..86d97271cbf 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -610,4 +610,25 @@ describe('query middleware', function() {
     return Test.updateOne({}, { name: 'bar' }).
       then(() => assert.equal(calledPost, 1));
   });
+
+  it('deleteOne with `document: true` but no `query` (gh-8555)', function() {
+    const mySchema = Schema({ name: String });
+
+    const docs = [];
+    mySchema.pre('deleteOne', { document: true }, function() {
+      docs.push(this);
+    });
+  
+    const Model = db.model('Test', mySchema);
+
+    return co(function*() {
+      const doc = yield Model.create({ name: 'test' });
+      yield doc.deleteOne();
+      assert.equal(docs.length, 1);
+      assert.strictEqual(docs[0], doc);
+
+      yield Model.deleteOne();
+      assert.equal(docs.length, 1);
+    });
+  });
 });

From 49b298d4df56623877b6154eb68784cc88513408 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 13:34:55 -0500
Subject: [PATCH 0514/2348] fix(query): run `deleteOne` hooks only on
 `Document#deleteOne()` when setting `options.document = true` for
 `Schema#pre()`

Fix #8555
---
 lib/helpers/query/applyQueryMiddleware.js | 22 +++++++++++++++++-----
 lib/schema.js                             | 10 +++++++++-
 test/query.middleware.test.js             |  2 +-
 3 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/lib/helpers/query/applyQueryMiddleware.js b/lib/helpers/query/applyQueryMiddleware.js
index 4210d528047..812d00b65a2 100644
--- a/lib/helpers/query/applyQueryMiddleware.js
+++ b/lib/helpers/query/applyQueryMiddleware.js
@@ -46,14 +46,15 @@ function applyQueryMiddleware(Query, model) {
   };
 
   const middleware = model.hooks.filter(hook => {
-    if (hook.name === 'updateOne' || hook.name === 'deleteOne') {
-      return hook.query == null || !!hook.query;
+    const contexts = _getContexts(hook);
+    if (hook.name === 'updateOne') {
+      return contexts.query == null || !!contexts.query;
     }
-    if (hook.name === 'remove') {
-      return !!hook.query;
+    if (hook.name === 'remove' || hook.name === 'deleteOne') {
+      return !!contexts.query || Object.keys(contexts).length === 0;
     }
     if (hook.name === 'validate') {
-      return !!hook.query;
+      return !!contexts.query;
     }
     return true;
   });
@@ -76,3 +77,14 @@ function applyQueryMiddleware(Query, model) {
         Query.prototype[`_${fn}`], null, kareemOptions);
     });
 }
+
+function _getContexts(hook) {
+  const ret = {};
+  if (hook.hasOwnProperty('query')) {
+    ret.query = hook.query;
+  }
+  if (hook.hasOwnProperty('document')) {
+    ret.document = hook.document;
+  }
+  return ret;
+}
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index 312aa6cd85c..03407386fc3 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1365,9 +1365,17 @@ Schema.prototype.queue = function(name, args) {
  *       console.log(this.getFilter());
  *     });
  *
+ *     toySchema.pre('deleteOne', function() {
+ *       // Runs when you call `Toy.deleteOne()`
+ *     });
+ *
+ *     toySchema.pre('deleteOne', { document: true }, function() {
+ *       // Runs when you call `doc.deleteOne()`
+ *     });
+ *
  * @param {String|RegExp} The method name or regular expression to match method name
  * @param {Object} [options]
- * @param {Boolean} [options.document] If `name` is a hook for both document and query middleware, set to `true` to run on document middleware.
+ * @param {Boolean} [options.document] If `name` is a hook for both document and query middleware, set to `true` to run on document middleware. For example, set `options.document` to `true` to apply this hook to `Document#deleteOne()` rather than `Query#deleteOne()`.
  * @param {Boolean} [options.query] If `name` is a hook for both document and query middleware, set to `true` to run on query middleware.
  * @param {Function} callback
  * @api public
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index 86d97271cbf..3b1f60bb803 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -618,7 +618,7 @@ describe('query middleware', function() {
     mySchema.pre('deleteOne', { document: true }, function() {
       docs.push(this);
     });
-  
+
     const Model = db.model('Test', mySchema);
 
     return co(function*() {

From 1ba7cbf874450b74c54756214191dd584be759b2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 15 Feb 2020 13:41:14 -0500
Subject: [PATCH 0515/2348] test: fix tests re: #8555

---
 lib/helpers/query/applyQueryMiddleware.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/query/applyQueryMiddleware.js b/lib/helpers/query/applyQueryMiddleware.js
index 812d00b65a2..a08baf87ff3 100644
--- a/lib/helpers/query/applyQueryMiddleware.js
+++ b/lib/helpers/query/applyQueryMiddleware.js
@@ -50,10 +50,10 @@ function applyQueryMiddleware(Query, model) {
     if (hook.name === 'updateOne') {
       return contexts.query == null || !!contexts.query;
     }
-    if (hook.name === 'remove' || hook.name === 'deleteOne') {
+    if (hook.name === 'deleteOne') {
       return !!contexts.query || Object.keys(contexts).length === 0;
     }
-    if (hook.name === 'validate') {
+    if (hook.name === 'validate' || hook.name === 'remove') {
       return !!contexts.query;
     }
     return true;

From 383ca15887387044a759b4b4a5caafca6ba667dc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 16 Feb 2020 12:55:54 -0500
Subject: [PATCH 0516/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index f8e80f13025..4b2bf68b086 100644
--- a/index.pug
+++ b/index.pug
@@ -283,6 +283,9 @@ html(lang='en')
               <a href="https://taxfreesnus.com/">
                 <img class="sponsor" src="https://images.opencollective.com/taxfreesnus-com/ebf869a/logo.png" style="height: 100px">
               </a>
+              <a href="https://searchpromocodes.com/">
+                <img class="sponsor" src="https://images.opencollective.com/searchpromocodes/68ae5dd/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 00e9ff883c93f430a60504aa0b0320725ff049c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 16 Feb 2020 12:58:52 -0500
Subject: [PATCH 0517/2348] chore: update sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 4b2bf68b086..a80ffb399ed 100644
--- a/index.pug
+++ b/index.pug
@@ -166,6 +166,9 @@ html(lang='en')
 
           <div class="sponsors">
             <div>
+              <a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
+                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/payment-ninja-mongoose.png" style="height: 100px">
+              </a>
               <a href="https://www.codefirst.co.uk/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fdde88120-e914-11e8-a662-278259d35390.png&height=100">
               </a>

From 2b9d3b181c9ad1e918b41c20afe709e82b8b51ac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 16 Feb 2020 18:56:02 -0500
Subject: [PATCH 0518/2348] fix(document): when setting nested array path to
 non-nested array, wrap values top-down rather than bottom up when possible

Fix #8544
---
 lib/helpers/arrayDepth.js | 28 ++++++++++++++++++++++++++++
 lib/schema/array.js       | 32 ++++++++++++++++++++++++++++++++
 test/document.test.js     | 23 +++++++++++++++++++++++
 3 files changed, 83 insertions(+)
 create mode 100644 lib/helpers/arrayDepth.js

diff --git a/lib/helpers/arrayDepth.js b/lib/helpers/arrayDepth.js
new file mode 100644
index 00000000000..0ac39efeb9e
--- /dev/null
+++ b/lib/helpers/arrayDepth.js
@@ -0,0 +1,28 @@
+'use strict';
+
+module.exports = arrayDepth;
+
+function arrayDepth(arr) {
+  if (!Array.isArray(arr)) {
+    return { min: 0, max: 0 };
+  }
+  if (arr.length === 0) {
+    return { min: 1, max: 1 };
+  }
+
+  const res = arrayDepth(arr[0]);
+  for (let i = 1; i < arr.length; ++i) {
+    const _res = arrayDepth(arr[i]);
+    if (_res.min < res.min) {
+      res.min = _res.min;
+    }
+    if (_res.max > res.max) {
+      res.max = _res.max;
+    }
+  }
+
+  res.min = res.min + 1;
+  res.max = res.max + 1;
+
+  return res;
+}
\ No newline at end of file
diff --git a/lib/schema/array.js b/lib/schema/array.js
index dcc3aae6dc2..80dbb33e2ec 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -11,6 +11,7 @@ const SchemaArrayOptions = require('../options/SchemaArrayOptions');
 const SchemaType = require('../schematype');
 const CastError = SchemaType.CastError;
 const Mixed = require('./mixed');
+const arrayDepth = require('../helpers/arrayDepth');
 const cast = require('../cast');
 const get = require('../helpers/get');
 const isOperator = require('../helpers/query/isOperator');
@@ -23,6 +24,8 @@ const getDiscriminatorByValue = require('../helpers/discriminator/getDiscriminat
 let MongooseArray;
 let EmbeddedDoc;
 
+const isNestedArraySymbol = Symbol('mongoose#isNestedArray');
+
 /**
  * Array SchemaType constructor
  *
@@ -71,6 +74,10 @@ function SchemaArray(key, cast, options, schemaOptions) {
 
     this.casterConstructor = caster;
 
+    if (this.casterConstructor instanceof SchemaArray) {
+      this.casterConstructor[isNestedArraySymbol] = true;
+    }
+
     if (typeof caster === 'function' &&
         !caster.$isArraySubdocument &&
         !caster.$isSchemaMap) {
@@ -256,6 +263,31 @@ SchemaArray.prototype.applyGetters = function(value, scope) {
   return SchemaType.prototype.applyGetters.call(this, value, scope);
 };
 
+SchemaArray.prototype._applySetters = function(value, scope, init, priorVal) {
+  if (this.casterConstructor instanceof SchemaArray &&
+      SchemaArray.options.castNonArrays &&
+      !this[isNestedArraySymbol]) {
+    // Check nesting levels and wrap in array if necessary
+    let depth = 0;
+    let arr = this;
+    while (arr != null &&
+      arr instanceof SchemaArray &&
+      !arr.$isMongooseDocumentArray) {
+      ++depth;
+      arr = arr.casterConstructor;
+    }
+
+    const valueDepth = arrayDepth(value);
+    if (valueDepth.min === valueDepth.max && valueDepth.max < depth) {
+      for (let i = valueDepth.max; i < depth; ++i) {
+        value = [value];
+      }
+    }
+  }
+
+  return SchemaType.prototype._applySetters.call(this, value, scope, init, priorVal);
+};
+
 /**
  * Casts values for set().
  *
diff --git a/test/document.test.js b/test/document.test.js
index f961eed0be0..f5eaf790846 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8725,4 +8725,27 @@ describe('document', function() {
       assert.equal(fromDb.placedItems['1'].image, 'updated');
     });
   });
+
+  it('setting nested array path to non-nested array wraps values top-down (gh-8544)', function() {
+    const positionSchema = mongoose.Schema({
+      coordinates: {
+        type: [[Number]],
+        required: true
+      },
+      lines: {
+        type: [[[Number]]],
+        required: true
+      }
+    });
+
+    const Position = db.model('Test', positionSchema);
+    const position = new Position();
+
+    position.coordinates = [1, 2];
+    position.lines = [3, 4];
+
+    const obj = position.toObject();
+    assert.deepEqual(obj.coordinates, [[1, 2]]);
+    assert.deepEqual(obj.lines, [[[3, 4]]]);
+  });
 });

From 384681b1f38511a8c7f6118bf72febb1297a459f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 19 Feb 2020 15:16:09 -0500
Subject: [PATCH 0519/2348] docs(plugins): add mongoose-cast-aggregation to
 list of plugins re: #8464

---
 docs/plugins.pug | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/plugins.pug b/docs/plugins.pug
index f681f26bc85..58327091485 100644
--- a/docs/plugins.pug
+++ b/docs/plugins.pug
@@ -87,6 +87,7 @@ block content
 
     * [mongoose-autopopulate](http://plugins.mongoosejs.io/plugins/autopopulate): Always [`populate()`](/docs/populate.html) certain fields in your Mongoose schemas.
     * [mongoose-lean-virtuals](http://plugins.mongoosejs.io/plugins/lean-virtuals): Attach virtuals to the results of Mongoose queries when using [`.lean()`](/docs/api.html#query_Query-lean).
+    * [mongoose-cast-aggregation](https://www.npmjs.com/package/mongoose-cast-aggregation)
 
     You can find a full list of officially supported plugins on [Mongoose's plugins search site](https://plugins.mongoosejs.io/).
 

From c312d96e1955df59824042e2512c065e5d205e70 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 19 Feb 2020 18:07:55 -0500
Subject: [PATCH 0520/2348] docs(aggregate): clarify that `Aggregate#unwind()`
 can take object parameters as well as strings

Fix #8594
---
 lib/aggregate.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index 4e2b8c6cb12..53ffa5cad4b 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -358,9 +358,10 @@ Aggregate.prototype.near = function(arg) {
  *
  *     aggregate.unwind("tags");
  *     aggregate.unwind("a", "b", "c");
+ *     aggregate.unwind({ path: '$tags', preserveNullAndEmptyArrays: true });
  *
  * @see $unwind http://docs.mongodb.org/manual/reference/aggregation/unwind/
- * @param {String} fields the field(s) to unwind
+ * @param {String|Object} fields the field(s) to unwind, either as field names or as [objects with options](https://docs.mongodb.com/manual/reference/operator/aggregation/unwind/#document-operand-with-options). If passing a string, prefixing the field name with '$' is optional. If passing an object, `path` must start with '$'.
  * @return {Aggregate}
  * @api public
  */

From 1629bae58695d6f3b53c4ed38e9a5e60480ffa49 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 10:53:32 -0500
Subject: [PATCH 0521/2348] test(document): repro #8565

---
 test/document.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index f5eaf790846..bef320759bf 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8748,4 +8748,25 @@ describe('document', function() {
     assert.deepEqual(obj.coordinates, [[1, 2]]);
     assert.deepEqual(obj.lines, [[[3, 4]]]);
   });
+
+  it('doesnt wipe out nested keys when setting nested key to empty object with minimize (gh-8565)', function() {
+    const opts = { autoIndex: false, autoCreate: false };
+    const schema1 = Schema({ plaid: { nestedKey: String } }, opts);
+    const schema2 = Schema({ plaid: { nestedKey: String } }, opts);
+    const schema3 = Schema({ plaid: { nestedKey: String } }, opts);
+
+    const Test1 = db.model('Test1', schema1);
+    const Test2 = db.model('Test2', schema2);
+    const Test3 = db.model('Test3', schema3);
+
+    const doc1 = new Test1({});
+    assert.deepEqual(doc1.toObject({ minimize: false }).plaid, {});
+
+    const doc2 = new Test2({ plaid: doc1.plaid });
+    assert.deepEqual(doc2.toObject({ minimize: false }).plaid, {});
+
+    const doc3 = new Test3({});
+    doc3.set({ plaid: doc2.plaid });
+    assert.deepEqual(doc3.toObject({ minimize: false }).plaid, {});
+  });
 });

From f4dc5a94d71bd885979f2e1be45e9ae131b29932 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 10:54:06 -0500
Subject: [PATCH 0522/2348] fix(document): dont leave nested key as undefined
 when setting nested key to empty object with minimize

Fix #8565
---
 lib/document.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index cd03cc42495..b89157a904a 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -893,7 +893,11 @@ Document.prototype.$set = function $set(path, val, type, options) {
       keys = Object.keys(path);
       const len = keys.length;
 
-      if (len === 0 && !this.schema.options.minimize) {
+      // `_skipMinimizeTopLevel` is because we may have deleted the top-level
+      // nested key to ensure key order.
+      const _skipMinimizeTopLevel = get(options, '_skipMinimizeTopLevel', false);
+      if (len === 0 && (!this.schema.options.minimize || _skipMinimizeTopLevel)) {
+        delete options._skipMinimizeTopLevel;
         if (val) {
           this.$set(val, {});
         }
@@ -924,6 +928,8 @@ Document.prototype.$set = function $set(path, val, type, options) {
         this._doc[key] != null &&
         Object.keys(this._doc[key]).length === 0) {
       delete this._doc[key];
+      // Make sure we set `{}` back even if we minimize re: gh-8565
+      options = Object.assign({}, options, { _skipMinimizeTopLevel: true });
     }
 
     if (typeof path[key] === 'object' &&

From cf6b45ed3936e74c9f27b4a6e4b59186717841c9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 10:59:20 -0500
Subject: [PATCH 0523/2348] fix(document): avoid throwing error if setting path
 to Mongoose document with nullish `_doc`

Re: #8565
---
 lib/document.js | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index b89157a904a..3d03860e550 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -875,21 +875,21 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
   if (typeof path !== 'string') {
     // new Document({ key: val })
-    if (path === null || path === void 0) {
+    if (path instanceof Document) {
+      if (path.$__isNested) {
+        path = path.toObject();
+      } else {
+        path = path._doc;
+      }
+    }
+
+    if (path == null) {
       const _ = path;
       path = val;
       val = _;
     } else {
       prefix = val ? val + '.' : '';
 
-      if (path instanceof Document) {
-        if (path.$__isNested) {
-          path = path.toObject();
-        } else {
-          path = path._doc;
-        }
-      }
-
       keys = Object.keys(path);
       const len = keys.length;
 

From 2afec3a82a499cd93b09ffb2fb5c419120b16491 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 11:24:44 -0500
Subject: [PATCH 0524/2348] fix(array): fix tests re: #8544

---
 lib/schema/array.js | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 80dbb33e2ec..86589f122b9 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -277,10 +277,13 @@ SchemaArray.prototype._applySetters = function(value, scope, init, priorVal) {
       arr = arr.casterConstructor;
     }
 
-    const valueDepth = arrayDepth(value);
-    if (valueDepth.min === valueDepth.max && valueDepth.max < depth) {
-      for (let i = valueDepth.max; i < depth; ++i) {
-        value = [value];
+    // No need to wrap empty arrays
+    if (value != null && value.length > 0) {
+      const valueDepth = arrayDepth(value);
+      if (valueDepth.min === valueDepth.max && valueDepth.max < depth) {
+        for (let i = valueDepth.max; i < depth; ++i) {
+          value = [value];
+        }
       }
     }
   }

From b20a45d5405a0365d17b4bc8cb913f8d770a5251 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 14:25:20 -0500
Subject: [PATCH 0525/2348] fix(virtualtype): correctly copy options when
 cloning

Fix #8587
---
 lib/virtualtype.js       |  2 +-
 test/virtualtype.test.js | 17 +++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100644 test/virtualtype.test.js

diff --git a/lib/virtualtype.js b/lib/virtualtype.js
index 1b5b68490a1..abac5f36ae1 100644
--- a/lib/virtualtype.js
+++ b/lib/virtualtype.js
@@ -55,7 +55,7 @@ VirtualType.prototype._applyDefaultGetters = function() {
  */
 
 VirtualType.prototype.clone = function() {
-  const clone = new VirtualType(this.name, this.options);
+  const clone = new VirtualType(this.options, this.path);
   clone.getters = [].concat(this.getters);
   clone.setters = [].concat(this.setters);
   return clone;
diff --git a/test/virtualtype.test.js b/test/virtualtype.test.js
new file mode 100644
index 00000000000..57523c984c1
--- /dev/null
+++ b/test/virtualtype.test.js
@@ -0,0 +1,17 @@
+'use strict';
+
+const VirtualType = require('../lib/virtualtype');
+const assert = require('assert');
+
+describe('VirtualType', function() {
+  describe('clone', function() {
+    it('copies path and options correctly (gh-8587)', function() {
+      const opts = { ref: 'User', localField: 'userId', foreignField: '_id' };
+      const virtual = new VirtualType(Object.assign({}, opts), 'users');
+
+      const clone = virtual.clone();
+      assert.equal(clone.path, 'users');
+      assert.deepEqual(clone.options, opts);
+    });
+  });
+});
\ No newline at end of file

From 5d3507d90b9ffd11d8091e1caba5bb2f6fd7bea7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 15:28:23 -0500
Subject: [PATCH 0526/2348] test(model): repro #8590

---
 test/model.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index e7b5f122d9a..5d0e716f372 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6426,4 +6426,22 @@ describe('Model', function() {
       assert.deepEqual(ops, ['validate', 'validate', 'save', 'save']);
     });
   });
+
+  it('bulkWrite sets discriminator filters (gh-8590)', function() {
+    const Animal = db.model('Test', Schema({ name: String }));
+    const Dog = Animal.discriminator('Dog', Schema({ breed: String }));
+
+    return co(function*() {
+      yield Dog.bulkWrite([{
+        updateOne: {
+          filter: { name: 'Pooka' },
+          update: { $set: { breed: 'Chorkie' } },
+          upsert: true
+        }
+      }]);
+      const res = yield Animal.findOne();
+      assert.ok(res instanceof Dog);
+      assert.strictEqual(res.breed, 'Chorkie');
+    });
+  });
 });

From a8f202094301e2101e53f058c23e0385a368e729 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 15:28:36 -0500
Subject: [PATCH 0527/2348] fix(model): add discriminator key to bulkWrite
 filters

Fix #8590
---
 lib/helpers/model/castBulkWrite.js | 56 +++++++++++++++++++-----------
 1 file changed, 35 insertions(+), 21 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index f724afb0b31..1d8e51b6353 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -13,6 +13,8 @@ const setDefaultsOnInsert = require('../setDefaultsOnInsert');
 
 module.exports = function castBulkWrite(model, op, options) {
   const now = model.base.now();
+  const schema = model.schema;
+
   if (op['insertOne']) {
     return (callback) => {
       const doc = new model(op['insertOne']['document']);
@@ -31,29 +33,29 @@ module.exports = function castBulkWrite(model, op, options) {
       });
     };
   } else if (op['updateOne']) {
-    op = op['updateOne'];
     return (callback) => {
       try {
-        if (!op['filter']) throw new Error('Must provide a filter object.');
-        if (!op['update']) throw new Error('Must provide an update object.');
+        if (!op['updateOne']['filter']) throw new Error('Must provide a filter object.');
+        if (!op['updateOne']['update']) throw new Error('Must provide an update object.');
 
-        op['filter'] = cast(model.schema, op['filter']);
-        op['update'] = castUpdate(model.schema, op['update'], {
+        _addDiscriminatorToObject(schema, op['updateOne']['filter']);
+        op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter']);
+        op['updateOne']['update'] = castUpdate(model.schema, op['updateOne']['update'], {
           strict: model.schema.options.strict,
           overwrite: false
         });
-        if (op.setDefaultsOnInsert) {
-          setDefaultsOnInsert(op['filter'], model.schema, op['update'], {
+        if (op['updateOne'].setDefaultsOnInsert) {
+          setDefaultsOnInsert(op['updateOne']['filter'], model.schema, op['updateOne']['update'], {
             setDefaultsOnInsert: true,
-            upsert: op.upsert
+            upsert: op['updateOne'].upsert
           });
         }
         if (model.schema.$timestamps != null) {
           const createdAt = model.schema.$timestamps.createdAt;
           const updatedAt = model.schema.$timestamps.updatedAt;
-          applyTimestampsToUpdate(now, createdAt, updatedAt, op['update'], {});
+          applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateOne']['update'], {});
         }
-        applyTimestampsToChildren(now, op['update'], model.schema);
+        applyTimestampsToChildren(now, op['updateOne']['update'], model.schema);
       } catch (error) {
         return callback(error, null);
       }
@@ -61,29 +63,29 @@ module.exports = function castBulkWrite(model, op, options) {
       callback(null);
     };
   } else if (op['updateMany']) {
-    op = op['updateMany'];
     return (callback) => {
       try {
-        if (!op['filter']) throw new Error('Must provide a filter object.');
-        if (!op['update']) throw new Error('Must provide an update object.');
+        if (!op['updateMany']['filter']) throw new Error('Must provide a filter object.');
+        if (!op['updateMany']['update']) throw new Error('Must provide an update object.');
 
-        op['filter'] = cast(model.schema, op['filter']);
-        op['update'] = castUpdate(model.schema, op['update'], {
+        _addDiscriminatorToObject(schema, op['updateMany']['filter']);
+        op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter']);
+        op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
           strict: model.schema.options.strict,
           overwrite: false
         });
-        if (op.setDefaultsOnInsert) {
-          setDefaultsOnInsert(op['filter'], model.schema, op['update'], {
+        if (op['updateMany'].setDefaultsOnInsert) {
+          setDefaultsOnInsert(op['updateMany']['filter'], model.schema, op['updateMany']['update'], {
             setDefaultsOnInsert: true,
-            upsert: op.upsert
+            upsert: op['updateMany'].upsert
           });
         }
         if (model.schema.$timestamps != null) {
           const createdAt = model.schema.$timestamps.createdAt;
           const updatedAt = model.schema.$timestamps.updatedAt;
-          applyTimestampsToUpdate(now, createdAt, updatedAt, op['update'], {});
+          applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateMany']['update'], {});
         }
-        applyTimestampsToChildren(now, op['update'], model.schema);
+        applyTimestampsToChildren(now, op['updateMany']['update'], model.schema);
       } catch (error) {
         return callback(error, null);
       }
@@ -92,6 +94,7 @@ module.exports = function castBulkWrite(model, op, options) {
     };
   } else if (op['replaceOne']) {
     return (callback) => {
+      _addDiscriminatorToObject(schema, op['replaceOne']['filter']);
       try {
         op['replaceOne']['filter'] = cast(model.schema,
           op['replaceOne']['filter']);
@@ -118,6 +121,7 @@ module.exports = function castBulkWrite(model, op, options) {
     };
   } else if (op['deleteOne']) {
     return (callback) => {
+      _addDiscriminatorToObject(schema, op['deleteOne']['filter']);
       try {
         op['deleteOne']['filter'] = cast(model.schema,
           op['deleteOne']['filter']);
@@ -129,6 +133,7 @@ module.exports = function castBulkWrite(model, op, options) {
     };
   } else if (op['deleteMany']) {
     return (callback) => {
+      _addDiscriminatorToObject(schema, op['deleteMany']['filter']);
       try {
         op['deleteMany']['filter'] = cast(model.schema,
           op['deleteMany']['filter']);
@@ -143,4 +148,13 @@ module.exports = function castBulkWrite(model, op, options) {
       callback(new Error('Invalid op passed to `bulkWrite()`'), null);
     };
   }
-};
\ No newline at end of file
+};
+
+function _addDiscriminatorToObject(schema, obj) {
+  if (schema == null) {
+    return;
+  }
+  if (schema.discriminatorMapping && !schema.discriminatorMapping.isRoot) {
+    obj[schema.discriminatorMapping.key] = schema.discriminatorMapping.value;
+  }
+}
\ No newline at end of file

From b895e017b6be282207bb22ad8e669daf546b0092 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 15:45:47 -0500
Subject: [PATCH 0528/2348] test(document): repro #8597

---
 test/document.test.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index bef320759bf..f3b55675816 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8769,4 +8769,33 @@ describe('document', function() {
     doc3.set({ plaid: doc2.plaid });
     assert.deepEqual(doc3.toObject({ minimize: false }).plaid, {});
   });
+
+  it('allows calling `validate()` in post validate hook without causing parallel validation error (gh-8597)', function() {
+    const EmployeeSchema = Schema({
+      name: String,
+      employeeNumber: {
+        type: String,
+        validate: v => v.length > 5
+      }
+    });
+    let called = 0;
+
+    EmployeeSchema.post('validate', function() {
+      ++called;
+      if (!this.employeeNumber && !this._employeeNumberRetrieved) {
+        this.employeeNumber = '123456';
+        this._employeeNumberRetrieved = true;
+        return this.validate();
+      }
+    });
+
+    const Employee = db.model('Test', EmployeeSchema);
+
+    return co(function*() {
+      const e = yield Employee.create({ name: 'foo' });
+      assert.equal(e.employeeNumber, '123456');
+      assert.ok(e._employeeNumberRetrieved);
+      assert.equal(called, 2);
+    });
+  });
 });

From bb25b0626a7dcedd8050f1177c80c9fb7646b54a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Feb 2020 15:55:59 -0500
Subject: [PATCH 0529/2348] fix(document): allow calling `validate()` in post
 validate hook without causing parallel validation error

Fix #8597
---
 lib/document.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 3d03860e550..e193b34a50d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2088,7 +2088,6 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
     }
 
     this.$__validate(pathsToValidate, options, (error) => {
-      this.$__.validating = null;
       this.$op = null;
       cb(error);
     });
@@ -2274,6 +2273,8 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     this.$__.cachedRequired = {};
     this.emit('validate', _this);
     this.constructor.emit('validate', _this);
+
+    this.$__.validating = null;
     if (validationError) {
       for (const key in validationError.errors) {
         // Make sure cast errors persist

From e0606f33fbb78bac32c92e9767c9f8b2742af780 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 Feb 2020 17:16:27 -0500
Subject: [PATCH 0530/2348] docs(middleware): clarify that updateOne and
 deleteOne hooks are query middleware by default, not document middleware

Fix #8581
---
 docs/middleware.pug | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index c232023c875..8122dec1eca 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -86,6 +86,13 @@ block content
     want to your middleware to run on [`Query.remove()`](./api.html#query_Query-remove)
     use [`schema.pre('remove', { query: true, document: false }, fn)`](./api.html#schema_Schema-pre).
 
+    **Note:** Unlike `schema.pre('remove')`, Mongoose registers `updateOne` and
+    `deleteOne` middleware on `Query#updateOne()` and `Query#deleteOne()` by default.
+    This means that both `doc.updateOne()` and `Model.updateOne()` trigger
+    `updateOne` hooks, but `this` refers to a query, not a document. To register
+    `updateOne` or `deleteOne` middleware as document middleware, use
+    `schema.pre('updateOne', { document: true, query: false })`.
+
     **Note:** The [`create()`](./api.html#model_Model.create) function fires `save()` hooks.
 
     <h3 id="pre"><a href="#pre">Pre</a></h3>
@@ -371,7 +378,7 @@ block content
     ```
 
     You **cannot** access the document being updated in `pre('updateOne')` or
-    `pre('findOneAndUpdate')` middleware. If you need to access the document
+    `pre('findOneAndUpdate')` query middleware. If you need to access the document
     that will be updated, you need to execute an explicit query for the document.
 
     ```javascript
@@ -381,6 +388,25 @@ block content
     });
     ```
 
+    However, if you define `pre('updateOne')` document middleware,
+    `this` will be the document being updated. That's because `pre('updateOne')`
+    document middleware hooks into [`Document#updateOne()`](/docs/api/document.html#document_Document-updateOne)
+    rather than `Query#updateOne()`.
+
+    ```javascript
+    schema.pre('updateOne', { document: true, query: false }, function() {
+      console.log('Updating');
+    });
+    const Model = mongoose.model('Test', schema);
+
+    const doc = new Model();
+    await doc.updateOne({ $set: { name: 'test' } }); // Prints "Updating"
+
+    // Doesn't print "Updating", because `Query#updateOne()` doesn't fire
+    // document middleware.
+    await Model.updateOne({}, { $set: { name: 'test' } });
+    ```
+
     <h3 id="error-handling-middleware"><a href="#error-handling-middleware">Error Handling Middleware</a></h3>
 
     _New in 4.5.0_

From 8bc18b7f37c6ae01a70297708b7a179a49182287 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 Feb 2020 17:41:21 -0500
Subject: [PATCH 0531/2348] chore: release 5.9.2

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 2581448138f..9cefb45fae0 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.9.2 / 2020-02-21
+==================
+ * fix(model): add discriminator key to bulkWrite filters #8590
+ * fix(document): when setting nested array path to non-nested array, wrap values top-down rather than bottom up when possible #8544
+ * fix(document): dont leave nested key as undefined when setting nested key to empty object with minimize #8565
+ * fix(document): avoid throwing error if setting path to Mongoose document with nullish `_doc` #8565
+ * fix(update): handle Binary type correctly with `runValidators` #8580
+ * fix(query): run `deleteOne` hooks only on `Document#deleteOne()` when setting `options.document = true` for `Schema#pre()` #8555
+ * fix(document): allow calling `validate()` in post validate hook without causing parallel validation error #8597
+ * fix(virtualtype): correctly copy options when cloning #8587
+ * fix(collection): skip creating capped collection if `autoCreate` set to `false` #8566
+ * docs(middleware): clarify that updateOne and deleteOne hooks are query middleware by default, not document middleware #8581
+ * docs(aggregate): clarify that `Aggregate#unwind()` can take object parameters as well as strings #8594
+
 5.9.1 / 2020-02-14
 ==================
  * fix(model): set session when calling `save()` with no changes #8571
diff --git a/package.json b/package.json
index 39ebfbdbc3d..8c24cd571dc 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.1",
+  "version": "5.9.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 483f379aec954ce02286fbbe714da0c0b90ef535 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 23 Feb 2020 19:12:42 -0500
Subject: [PATCH 0532/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index a80ffb399ed..f30149a9008 100644
--- a/index.pug
+++ b/index.pug
@@ -289,6 +289,9 @@ html(lang='en')
               <a href="https://searchpromocodes.com/">
                 <img class="sponsor" src="https://images.opencollective.com/searchpromocodes/68ae5dd/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://unscramblex.com/">
+                <img class="sponsor" src="https://images.opencollective.com/unscramblex/87d6a68/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 7c49315ab80fc77da49e81423be495466d1634ae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 11:46:54 -0500
Subject: [PATCH 0533/2348] test(model): repro #8559

---
 test/model.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 5d0e716f372..81450b184b6 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5963,6 +5963,32 @@ describe('Model', function() {
       });
     });
 
+    it('syncIndexes() with different key order (gh-8559)', function() {
+      this.timeout(5000);
+
+      return co(function*() {
+        yield db.dropDatabase();
+
+        const opts = { autoIndex: false };
+        let schema = new Schema({ name: String, age: Number }, opts);
+        schema.index({ name: 1, _id: 1 });
+
+        let M = db.model('Test', schema);
+
+        let dropped = yield M.syncIndexes();
+        assert.deepEqual(dropped, []);
+
+        // New model, same collection, different key order
+        schema = new Schema({ name: String, age: Number }, opts);
+        schema.index({ name: 1 });
+        db.deleteModel(/Test/);
+        M = db.model('Test', schema);
+
+        dropped = yield M.syncIndexes();
+        assert.deepEqual(dropped, ['name_1__id_1']);
+      });
+    });
+
     it('using `new db.model()()` (gh-6698)', function(done) {
       db.model('Test', new Schema({
         name: String

From 193d61c1c39c6e9aa1a0bbc0d5f70c340bb56333 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 11:47:16 -0500
Subject: [PATCH 0534/2348] fix(model): make `syncIndexes()` and
 `cleanIndexes()` drop compound indexes with `_id` that aren't in the schema

Fix #8559
---
 lib/helpers/indexes/isDefaultIdIndex.js | 18 ++++++++++++++++++
 lib/model.js                            |  6 +++---
 2 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100644 lib/helpers/indexes/isDefaultIdIndex.js

diff --git a/lib/helpers/indexes/isDefaultIdIndex.js b/lib/helpers/indexes/isDefaultIdIndex.js
new file mode 100644
index 00000000000..c975dcfc389
--- /dev/null
+++ b/lib/helpers/indexes/isDefaultIdIndex.js
@@ -0,0 +1,18 @@
+'use strict';
+
+const get = require('../get');
+
+module.exports = function isDefaultIdIndex(index) {
+  if (Array.isArray(index)) {
+    // Mongoose syntax
+    const keys = Object.keys(index[0]);
+    return keys.length === 1 && keys[0] === '_id' && index[0]._id !== 'hashed';
+  }
+
+  if (typeof index !== 'object') {
+    return false;
+  }
+
+  const key = get(index, 'key', {});
+  return Object.keys(key).length === 1 && key.hasOwnProperty('_id');
+};
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index dfd9e0a6251..582948f5a06 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -37,6 +37,7 @@ const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminato
 const getModelsMapForPopulate = require('./helpers/populate/getModelsMapForPopulate');
 const immediate = require('./helpers/immediate');
 const internalToObjectOptions = require('./options').internalToObjectOptions;
+const isDefaultIdIndex = require('./helpers/indexes/isDefaultIdIndex');
 const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedInclusive');
 const get = require('./helpers/get');
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
@@ -1394,7 +1395,7 @@ Model.cleanIndexes = function cleanIndexes(callback) {
       for (const index of indexes) {
         let found = false;
         // Never try to drop `_id` index, MongoDB server doesn't allow it
-        if (index.key._id) {
+        if (isDefaultIdIndex(index)) {
           continue;
         }
 
@@ -1601,8 +1602,7 @@ function _ensureIndexes(model, options, callback) {
   };
 
   for (const index of indexes) {
-    const keys = Object.keys(index[0]);
-    if (keys.length === 1 && keys[0] === '_id' && index[0]._id !== 'hashed') {
+    if (isDefaultIdIndex(index)) {
       console.warn('mongoose: Cannot specify a custom index on `_id` for ' +
         'model name "' + model.modelName + '", ' +
         'MongoDB does not allow overwriting the default `_id` index. See ' +

From 352502ced072be68d235bfcc1aac454340bb53b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 11:58:42 -0500
Subject: [PATCH 0535/2348] test: clean up test failure from #8559

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 81450b184b6..9f4d110db0a 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6084,7 +6084,7 @@ describe('Model', function() {
       const Model = db.model('User', userSchema);
 
       return co(function*() {
-        yield Model.collection.drop();
+        yield Model.collection.drop().catch(err => {});
         yield Model.createCollection();
 
         // If the collection is not created, the following will throw

From d0ae2ccc009dc9034883e3e9d0d53c92bb3822e5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 12:35:22 -0500
Subject: [PATCH 0536/2348] fix(browser): make `mongoose.model()` return a
 class in the browser to allow hydrating populated data in the browser

Fix #8605
---
 lib/browser.js     | 19 +++++++++++++++----
 test/model.test.js |  2 +-
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/lib/browser.js b/lib/browser.js
index 4b7df9f34df..0a65dd78b62 100644
--- a/lib/browser.js
+++ b/lib/browser.js
@@ -124,14 +124,25 @@ exports.utils = require('./utils.js');
 exports.Document = DocumentProvider();
 
 /**
- * function stub for model
+ * Return a new browser model. In the browser, a model is just
+ * a simplified document with a schema - it does **not** have
+ * functions like `findOne()`, etc.
  *
  * @method model
  * @api public
- * @return null
+ * @param {String} name
+ * @param {Schema} schema
+ * @return Class
  */
-exports.model = function() {
-  return null;
+exports.model = function(name, schema) {
+  class Model extends exports.Document {
+    constructor(obj, fields) {
+      super(obj, schema, fields);
+    }
+  }
+  Model.modelName = name;
+
+  return Model;
 };
 
 /*!
diff --git a/test/model.test.js b/test/model.test.js
index 9f4d110db0a..58b625d07dc 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6084,7 +6084,7 @@ describe('Model', function() {
       const Model = db.model('User', userSchema);
 
       return co(function*() {
-        yield Model.collection.drop().catch(err => {});
+        yield Model.collection.drop().catch(() => {});
         yield Model.createCollection();
 
         // If the collection is not created, the following will throw

From ebb0ca2d93725751ee18d7a47770738d45468a72 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 13:47:58 -0500
Subject: [PATCH 0537/2348] test(document): repro #8603

---
 test/document.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index f3b55675816..114e81a1c6a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8798,4 +8798,30 @@ describe('document', function() {
       assert.equal(called, 2);
     });
   });
+
+  it('sets defaults when setting single nested subdoc (gh-8603)', function() {
+    const nestedSchema = Schema({
+      name: String,
+      status: { type: String, default: 'Pending' }
+    });
+
+    const Test = db.model('Test', {
+      nested: nestedSchema
+    });
+
+    return co(function*() {
+      let doc = yield Test.create({ nested: { name: 'foo' } });
+      assert.equal(doc.nested.status, 'Pending');
+
+      doc = yield Test.findById(doc);
+      assert.equal(doc.nested.status, 'Pending');
+
+      Object.assign(doc, { nested: { name: 'bar' } });
+      assert.equal(doc.nested.status, 'Pending');
+      yield doc.save();
+
+      doc = yield Test.findById(doc);
+      assert.equal(doc.nested.status, 'Pending');
+    });
+  });
 });

From 8f6b1d71fbab81ffe8d39ee3e3a8b6e02adf0813 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 13:48:23 -0500
Subject: [PATCH 0538/2348] fix(document): set subpath defaults when
 overwriting single nested subdoc

Fix #8603
---
 lib/types/subdocument.js | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index f6bc8cd8ee8..521237aee72 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -38,7 +38,14 @@ function Subdocument(value, fields, parent, skipId, options) {
       if (!this.$__.activePaths.states.modify[key] &&
           !this.$__.activePaths.states.default[key] &&
           !this.$__.$setCalled.has(key)) {
-        delete this._doc[key];
+        const schematype = this.schema.path(key);
+        const def = schematype == null ? void 0 : schematype.getDefault(this);
+        if (def === void 0) {
+          delete this._doc[key];
+        } else {
+          this._doc[key] = def;
+          this.$__.activePaths.default(key);
+        }
       }
     }
   }

From 0dc34713b6e11e0cb898a3bef7b9d55ffa4612bc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 17:44:11 -0500
Subject: [PATCH 0539/2348] docs: fix out of date links to tumblr

Fix #8599
---
 docs/guide.pug | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index f2ea7211345..a0a962609a8 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -827,7 +827,7 @@ block content
 
     The `versionKey` is a property set on each document when first created by
     Mongoose. This keys value contains the internal
-    [revision](http://aaronheckmann.tumblr.com/post/48943525537/mongoose-v3-part-1-versioning)
+    [revision](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)
     of the document. The `versionKey` option is a string that represents the
     path to use for versioning. The default is `__v`. If this conflicts with
     your application you can configure as such:
@@ -867,7 +867,7 @@ block content
 
     Document versioning can also be disabled by setting the `versionKey` to
     `false`.
-    _DO NOT disable versioning unless you [know what you are doing](http://aaronheckmann.tumblr.com/post/48943525537/mongoose-v3-part-1-versioning)._
+    _DO NOT disable versioning unless you [know what you are doing](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)._
 
     ```javascript
     new Schema({..}, { versionKey: false });

From 57ca9b7f35876902c20bee69a044bafc58fab580 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 17:57:32 -0500
Subject: [PATCH 0540/2348] docs(connection+index): add warnings to explain
 that bufferMaxEntries does nothing with `useUnifiedTopology`

Fix #8604
---
 docs/connections.pug | 12 +++++++-----
 lib/connection.js    |  2 +-
 lib/index.js         |  4 ++--
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 79cc2468eb8..dd776fa4df9 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -180,20 +180,22 @@ block content
     * `reconnectInterval` - See `reconnectTries`
     * `bufferMaxEntries`  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
 
+    The following options are important for tuning Mongoose only if you are
+    running **with** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
+
+    * `serverSelectionTimeoutMS` - With `useUnifiedTopology`, the MongoDB driver will try to find a server to send any given operation to, and keep retrying for `serverSelectionTimeoutMS` milliseconds. If not set, the MongoDB driver defaults to using `30000` (30 seconds).
+
     Example:
 
     ```javascript
     const options = {
       useNewUrlParser: true,
+      useUnifiedTopology: true,
       useCreateIndex: true,
       useFindAndModify: false,
       autoIndex: false, // Don't build indexes
-      reconnectTries: Number.MAX_VALUE, // Never stop trying to reconnect
-      reconnectInterval: 500, // Reconnect every 500ms
       poolSize: 10, // Maintain up to 10 socket connections
-      // If not connected, return errors immediately rather than waiting for reconnect
-      bufferMaxEntries: 0,
-      connectTimeoutMS: 10000, // Give up initial connection after 10 seconds
+      serverSelectionTimeoutMS: 5000, // Keep trying to send operations for 5 seconds
       socketTimeoutMS: 45000, // Close sockets after 45 seconds of inactivity
       family: 4 // Use IPv4, skip trying IPv6
     };
diff --git a/lib/connection.js b/lib/connection.js
index e86b67c6149..abd32f39c72 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -550,7 +550,7 @@ Connection.prototype.onOpen = function() {
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
  * @param {Class} [options.promiseLibrary] Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
  * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
- * @param {Number} [options.bufferMaxEntries] The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
+ * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
  * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
diff --git a/lib/index.js b/lib/index.js
index cc2c77e75d3..4ce35c024a9 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -257,7 +257,7 @@ Mongoose.prototype.get = Mongoose.prototype.set;
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
  * @param {Class} [options.promiseLibrary] Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
  * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
- * @param {Number} [options.bufferMaxEntries] The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
+ * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
  * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
@@ -317,7 +317,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
  * @param {Class} [options.promiseLibrary] Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
  * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
- * @param {Number} [options.bufferMaxEntries] The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
+ * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
  * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.

From 9f718206c1d6318db171b43c73e277f0b5cffc9f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 18:21:49 -0500
Subject: [PATCH 0541/2348] docs(document+model+query): add
 `options.timestamps` parameter docs to `findOneAndUpdate()` and
 `findByIdAndUpdate()`

Fix #8619
---
 lib/document.js | 6 +++++-
 lib/model.js    | 4 +++-
 lib/query.js    | 3 ++-
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index e193b34a50d..ff333f2dfb1 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -711,7 +711,11 @@ Document.prototype.update = function update() {
  *
  * @see Model.updateOne #model_Model.updateOne
  * @param {Object} doc
- * @param {Object} options
+ * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
+ * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and the [Mongoose lean tutorial](/docs/tutorials/lean.html).
+ * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Function} callback
  * @return {Query}
  * @api public
diff --git a/lib/model.js b/lib/model.js
index 582948f5a06..cc09aa4b7ec 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2472,6 +2472,7 @@ Model.$where = function $where() {
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback]
  * @return {Query}
  * @see Tutorial /docs/tutorials/findoneandupdate.html
@@ -2610,6 +2611,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and the [Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndUpdate #model_Model.findOneAndUpdate
@@ -3686,7 +3688,7 @@ Model.updateMany = function updateMany(conditions, doc, options, callback) {
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
- * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] params are (error, writeOpResult)
  * @return {Query}
  * @see Query docs https://mongoosejs.com/docs/queries.html
diff --git a/lib/query.js b/lib/query.js
index 4e6d007aa10..7eac97cda98 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2938,6 +2938,7 @@ function prepareDiscriminatorCriteria(query) {
  * @param {Boolean} [options.multipleCastError] by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] optional params are (error, doc), _unless_ `rawResult` is used, in which case params are (error, writeOpResult)
  * @see Tutorial /docs/tutorials/findoneandupdate.html
  * @see mongodb http://www.mongodb.org/display/DOCS/findAndModify+Command
@@ -4034,7 +4035,7 @@ Query.prototype.updateMany = function(conditions, doc, options, callback) {
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
- * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Function} [callback] params are (error, writeOpResult)
  * @return {Query} this
  * @see Model.update #model_Model.update

From 5f79b1aab037b92114e0ee19423b5eeeb110b619 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Feb 2020 18:31:01 -0500
Subject: [PATCH 0542/2348] fix: upgrade mongodb driver -> 3.5.4

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 8c24cd571dc..2096ed9a219 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.5.3",
+    "mongodb": "3.5.4",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",

From dd567464641de31ff9b043faa7c6b608551bba5c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Feb 2020 10:35:10 -0500
Subject: [PATCH 0543/2348] test(document): repro #8626 part 1

---
 test/document.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 114e81a1c6a..20ca1a3ffbc 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8824,4 +8824,17 @@ describe('document', function() {
       assert.equal(doc.nested.status, 'Pending');
     });
   });
+
+  it('handles validating single nested paths when specified in `pathsToValidate` (gh-8626)', function() {
+    const nestedSchema = Schema({
+      name: { type: String, validate: v => v.length > 2 }
+    });
+    const schema = Schema({ nested: nestedSchema });
+    const Model = mongoose.model('Test', schema);
+
+    const doc = new Model({ nested: { name: 'a' } });
+    return doc.validate(['nested.name']).then(() => assert.ok(false), err => {
+      assert.ok(err.errors['nested.name']);
+    });
+  });
 });

From b1a094fe1f4f73b7b5dff2f2ae8ccf90ffe06065 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Feb 2020 10:35:16 -0500
Subject: [PATCH 0544/2348] fix(document): run validation on single nested
 paths when a single nested subpath is in `pathsToValidate`

Re: #8626
---
 lib/document.js | 33 +++++++++++++++++++++++----------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index ff333f2dfb1..0119641cde2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2300,8 +2300,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   const skipSchemaValidators = pathDetails[1];
 
   if (Array.isArray(pathsToValidate)) {
-    const _pathsToValidate = new Set(pathsToValidate);
-    paths = paths.filter(p => _pathsToValidate.has(p));
+    paths = _handlePathsToValidate(paths, pathsToValidate);
   }
 
   if (paths.length === 0) {
@@ -2387,6 +2386,26 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   }
 };
 
+/*!
+ * ignore
+ */
+
+function _handlePathsToValidate(paths, pathsToValidate) {
+  const _pathsToValidate = new Set(pathsToValidate);
+  for (const path of pathsToValidate) {
+    if (path.indexOf('.') === -1) {
+      continue;
+    }
+    const pieces = path.split('.');
+    let cur = pieces[0];
+    for (let i = 1; i < pieces.length; ++i) {
+      _pathsToValidate.add(cur);
+      cur = cur + '.' + pieces[i];
+    }
+  }
+  return paths.filter(p => _pathsToValidate.has(p));
+}
+
 /**
  * Executes registered validation rules (skipping asynchronous validators) for this document.
  *
@@ -2433,14 +2452,8 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
 
-  if (pathsToValidate && pathsToValidate.length) {
-    const tmp = [];
-    for (let i = 0; i < paths.length; ++i) {
-      if (pathsToValidate.indexOf(paths[i]) !== -1) {
-        tmp.push(paths[i]);
-      }
-    }
-    paths = tmp;
+  if (Array.isArray(pathsToValidate)) {
+    paths = _handlePathsToValidate(paths, pathsToValidate);
   }
 
   const validating = {};

From 3eee8404c2ab4a369488cbd6144e5763b42cddb6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Feb 2020 11:12:54 -0500
Subject: [PATCH 0545/2348] fix(document): make calling `validate()` with
 single nested subpath only validate that single nested subpath

Fix #8626
---
 lib/document.js       | 17 +++++++++++++++--
 test/document.test.js |  6 ++++--
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0119641cde2..3965d1cc8ad 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2392,6 +2392,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
 
 function _handlePathsToValidate(paths, pathsToValidate) {
   const _pathsToValidate = new Set(pathsToValidate);
+  const parentPaths = new Map([]);
   for (const path of pathsToValidate) {
     if (path.indexOf('.') === -1) {
       continue;
@@ -2399,11 +2400,23 @@ function _handlePathsToValidate(paths, pathsToValidate) {
     const pieces = path.split('.');
     let cur = pieces[0];
     for (let i = 1; i < pieces.length; ++i) {
-      _pathsToValidate.add(cur);
+      // Since we skip subpaths under single nested subdocs to
+      // avoid double validation, we need to add back the
+      // single nested subpath if the user asked for it (gh-8626)
+      parentPaths.set(cur, path);
       cur = cur + '.' + pieces[i];
     }
   }
-  return paths.filter(p => _pathsToValidate.has(p));
+
+  const ret = [];
+  for (const path of paths) {
+    if (_pathsToValidate.has(path)) {
+      ret.push(path);
+    } else if (parentPaths.has(path)) {
+      ret.push(parentPaths.get(path));
+    }
+  }
+  return ret;
 }
 
 /**
diff --git a/test/document.test.js b/test/document.test.js
index 20ca1a3ffbc..ba33bf35022 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8827,14 +8827,16 @@ describe('document', function() {
 
   it('handles validating single nested paths when specified in `pathsToValidate` (gh-8626)', function() {
     const nestedSchema = Schema({
-      name: { type: String, validate: v => v.length > 2 }
+      name: { type: String, validate: v => v.length > 2 },
+      age: { type: Number, validate: v => v < 200 }
     });
     const schema = Schema({ nested: nestedSchema });
     const Model = mongoose.model('Test', schema);
 
-    const doc = new Model({ nested: { name: 'a' } });
+    const doc = new Model({ nested: { name: 'a', age: 9001 } });
     return doc.validate(['nested.name']).then(() => assert.ok(false), err => {
       assert.ok(err.errors['nested.name']);
+      assert.ok(!err.errors['nested.age']);
     });
   });
 });

From dc217d8bb385c57fccc2038732620fcf0b982dae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Feb 2020 18:50:23 -0500
Subject: [PATCH 0546/2348] test(update): reuse collection names and
 connections for update tests

Re: #8481
---
 test/model.update.test.js | 231 +++++++++++++++++++-------------------
 1 file changed, 117 insertions(+), 114 deletions(-)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 11688e0ddb4..9ca875ba848 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -17,7 +17,7 @@ const ObjectId = Schema.Types.ObjectId;
 const DocumentObjectId = mongoose.Types.ObjectId;
 const CastError = mongoose.Error.CastError;
 
-describe('model: update:', function() {
+describe('model: update: XYZ', function() {
   let post;
   const title = 'Tobi';
   const author = 'Brian';
@@ -28,9 +28,11 @@ describe('model: update:', function() {
   let BlogPost;
   let db;
 
-  beforeEach(function() {
+  before(function() {
     db = start();
+  });
 
+  beforeEach(function() {
     Comments = new Schema({});
 
     Comments.add({
@@ -101,7 +103,8 @@ describe('model: update:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(() => {
+  afterEach(function() {
+    this.timeout(5000);
     const arr = [];
 
     if (db.models == null) {
@@ -525,7 +528,7 @@ describe('model: update:', function() {
 
   it('handles $pull from Mixed arrays (gh-735)', function(done) {
     const schema = new Schema({comments: []});
-    const M = db.model('gh-735', schema, 'gh-735_' + random());
+    const M = db.model('Test', schema);
     M.create({comments: [{name: 'node 0.8'}]}, function(err, doc) {
       assert.ifError(err);
       M.update({_id: doc._id}, {$pull: {comments: {name: 'node 0.8'}}}, function(err, affected) {
@@ -551,7 +554,7 @@ describe('model: update:', function() {
       components: [componentSchema]
     });
 
-    const Project = db.model('1057-project', projectSchema, '1057-' + random());
+    const Project = db.model('Test', projectSchema);
 
     Project.create({name: 'my project'}, function(err, project) {
       assert.ifError(err);
@@ -580,7 +583,7 @@ describe('model: update:', function() {
 
   it('handles nested paths starting with numbers (gh-1062)', function(done) {
     const schema = new Schema({counts: Schema.Types.Mixed});
-    const M = db.model('gh-1062', schema, '1062-' + random());
+    const M = db.model('Test', schema);
     M.create({counts: {}}, function(err, m) {
       assert.ifError(err);
       M.update({}, {$inc: {'counts.1': 1, 'counts.1a': 10}}, function(err) {
@@ -597,7 +600,7 @@ describe('model: update:', function() {
 
   it('handles positional operators with referenced docs (gh-1572)', function(done) {
     const so = new Schema({title: String, obj: [String]});
-    const Some = db.model('Some' + random(), so);
+    const Some = db.model('Test', so);
 
     Some.create({obj: ['a', 'b', 'c']}, function(err, s) {
       assert.ifError(err);
@@ -617,7 +620,7 @@ describe('model: update:', function() {
 
   it('use .where for update condition (gh-2170)', function(done) {
     const so = new Schema({num: Number});
-    const Some = db.model('gh-2170' + random(), so);
+    const Some = db.model('Test', so);
 
     Some.create([{num: 1}, {num: 1}], function(err, docs) {
       assert.ifError(err);
@@ -660,7 +663,7 @@ describe('model: update:', function() {
       }
 
       const schema = new Schema({name: String, age: Number, x: String});
-      const M = db.model('setoninsert-' + random(), schema);
+      const M = db.model('Test', schema);
 
       const match = {name: 'set on insert'};
       const op = {$setOnInsert: {age: '47'}, x: 'inserted'};
@@ -693,7 +696,7 @@ describe('model: update:', function() {
       }
 
       const schema = new Schema({name: String, n: [{x: Number}]});
-      const M = db.model('setoninsert-' + random(), schema);
+      const M = db.model('Test', schema);
 
       M.create({name: '2.4'}, function(err, created) {
         assert.ifError(err);
@@ -755,7 +758,7 @@ describe('model: update:', function() {
       }
 
       const schema = new Schema({name: String, n: [{x: Number}]});
-      const M = db.model('setoninsert-' + random(), schema);
+      const M = db.model('Test', schema);
 
       const m = new M({name: '2.6', n: [{x: 0}]});
       m.save(function(error, m) {
@@ -784,7 +787,7 @@ describe('model: update:', function() {
       }
 
       const schema = new Schema({name: String, lastModified: Date, lastModifiedTS: Date});
-      const M = db.model('gh-2019', schema);
+      const M = db.model('Test', schema);
 
       const m = new M({name: '2.6'});
       m.save(function(error) {
@@ -810,7 +813,7 @@ describe('model: update:', function() {
   describe('{overwrite: true}', function() {
     it('overwrite works', function(done) {
       const schema = new Schema({mixed: {}}, { minimize: false });
-      const M = db.model('updatesmixed-' + random(), schema);
+      const M = db.model('Test', schema);
 
       M.create({mixed: 'something'}, function(err, created) {
         assert.ifError(err);
@@ -831,7 +834,7 @@ describe('model: update:', function() {
     it('overwrites all properties', function(done) {
       const sch = new Schema({title: String, subdoc: {name: String, num: Number}});
 
-      const M = db.model('updateover' + random(), sch);
+      const M = db.model('Test', sch);
 
       M.create({subdoc: {name: 'that', num: 1}}, function(err, doc) {
         assert.ifError(err);
@@ -852,7 +855,7 @@ describe('model: update:', function() {
     it('allows users to blow it up', function(done) {
       const sch = new Schema({title: String, subdoc: {name: String, num: Number}});
 
-      const M = db.model('updateover' + random(), sch);
+      const M = db.model('Test', sch);
 
       M.create({subdoc: {name: 'that', num: 1, title: 'hello'}}, function(err, doc) {
         assert.ifError(err);
@@ -873,7 +876,7 @@ describe('model: update:', function() {
 
   it('casts empty arrays', function(done) {
     const so = new Schema({arr: []});
-    const Some = db.model('1838-' + random(), so);
+    const Some = db.model('Test', so);
 
     Some.create({arr: ['a']}, function(err, s) {
       if (err) {
@@ -899,7 +902,7 @@ describe('model: update:', function() {
   describe('defaults and validators (gh-860)', function() {
     it('applies defaults on upsert', function(done) {
       const s = new Schema({topping: {type: String, default: 'bacon'}, base: String});
-      const Breakfast = db.model('gh-860-0', s);
+      const Breakfast = db.model('Test', s);
       const updateOptions = {upsert: true, setDefaultsOnInsert: true};
       Breakfast.update({}, {base: 'eggs'}, updateOptions, function(error) {
         assert.ifError(error);
@@ -921,7 +924,7 @@ describe('model: update:', function() {
         embedded: EmbeddedSchema
       });
 
-      const Parent = db.model('gh4911', ParentSchema);
+      const Parent = db.model('Parent', ParentSchema);
 
       const newDoc = {
         _id: new mongoose.Types.ObjectId(),
@@ -938,7 +941,7 @@ describe('model: update:', function() {
 
     it('doesnt set default on upsert if query sets it', function(done) {
       const s = new Schema({topping: {type: String, default: 'bacon'}, base: String});
-      const Breakfast = db.model('gh-860-1', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {upsert: true, setDefaultsOnInsert: true};
       Breakfast.update({topping: 'sausage'}, {base: 'eggs'}, updateOptions, function(error) {
@@ -954,7 +957,7 @@ describe('model: update:', function() {
 
     it('properly sets default on upsert if query wont set it', function(done) {
       const s = new Schema({topping: {type: String, default: 'bacon'}, base: String});
-      const Breakfast = db.model('gh-860-2', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {upsert: true, setDefaultsOnInsert: true};
       Breakfast.update({topping: {$ne: 'sausage'}}, {base: 'eggs'}, updateOptions, function(error) {
@@ -976,7 +979,7 @@ describe('model: update:', function() {
         }
       });
 
-      const M = db.model('gh4456', schema);
+      const M = db.model('Test', schema);
 
       const opts = { upsert: true, setDefaultsOnInsert: true };
       M.update({}, {}, opts, function(error) {
@@ -997,7 +1000,7 @@ describe('model: update:', function() {
         }
       });
 
-      const M = db.model('gh6034', schema);
+      const M = db.model('Test', schema);
 
       const opts = { upsert: true, setDefaultsOnInsert: true, omitUndefined: true };
       M.update({}, {}, opts, function(error) {
@@ -1025,7 +1028,7 @@ describe('model: update:', function() {
           }
         }
       });
-      const Breakfast = db.model('gh-860-3', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {upsert: true, setDefaultsOnInsert: true, runValidators: true};
       Breakfast.update({}, {topping: 'bacon', base: 'eggs'}, updateOptions, function(error) {
@@ -1053,7 +1056,7 @@ describe('model: update:', function() {
           }
         }
       });
-      const Breakfast = db.model('gh-860-4', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {runValidators: true, context: 'query'};
       Breakfast.update({}, {$unset: {steak: ''}, $setOnInsert: {eggs: 'softboiled'}}, updateOptions, function(error) {
@@ -1092,7 +1095,7 @@ describe('model: update:', function() {
         eggs: {type: Number, min: 4, max: 6},
         bacon: {type: String, match: /strips/}
       });
-      const Breakfast = db.model('gh-860-5', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {runValidators: true};
       Breakfast.update({}, {$set: {steak: 'ribeye', eggs: 3, bacon: '3 strips'}}, updateOptions, function(error) {
@@ -1125,7 +1128,7 @@ describe('model: update:', function() {
         eggs: {type: Number, min: 4, max: 6},
         bacon: {type: String, match: /strips/}
       });
-      const Breakfast = db.model('gh-860-6', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {runValidators: true};
       Breakfast.update({}, {$set: {steak: 'tofu', eggs: 2, bacon: '3 strips'}}, updateOptions, function(error) {
@@ -1142,7 +1145,7 @@ describe('model: update:', function() {
         steak: {type: String, required: true},
         eggs: {type: Number, min: 4}
       });
-      const Breakfast = db.model('gh-860-7', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {runValidators: true};
       Breakfast.update({}, {$inc: {eggs: 1}}, updateOptions, function(error) {
@@ -1155,7 +1158,7 @@ describe('model: update:', function() {
       const s = new Schema({
         toppings: [{name: {type: String, enum: ['bacon', 'cheese']}}]
       });
-      const Breakfast = db.model('gh-860-8', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {runValidators: true};
       Breakfast.update(
@@ -1173,7 +1176,7 @@ describe('model: update:', function() {
       const s = new Schema({
         toppings: [{name: {type: String, enum: ['bacon', 'cheese']}}]
       });
-      const Breakfast = db.model('gh-7536', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {
         runValidators: true,
@@ -1202,7 +1205,7 @@ describe('model: update:', function() {
         file: FileSchema
       });
 
-      const Company = db.model('gh4479', CompanySchema);
+      const Company = db.model('Test', CompanySchema);
       const update = { file: { name: '' } };
       const options = { runValidators: true };
       Company.update({}, update, options, function(error) {
@@ -1216,7 +1219,7 @@ describe('model: update:', function() {
 
   it('works with $set and overwrite (gh-2515)', function(done) {
     const schema = new Schema({breakfast: String});
-    const M = db.model('gh-2515', schema);
+    const M = db.model('Test', schema);
 
     M.create({breakfast: 'bacon'}, function(error, doc) {
       assert.ifError(error);
@@ -1237,7 +1240,7 @@ describe('model: update:', function() {
 
   it('successfully casts set with nested mixed objects (gh-2796)', function(done) {
     const schema = new Schema({breakfast: {}});
-    const M = db.model('gh-2796', schema);
+    const M = db.model('Test', schema);
 
     M.create({}, function(error, doc) {
       assert.ifError(error);
@@ -1259,7 +1262,7 @@ describe('model: update:', function() {
 
   it('handles empty update with promises (gh-2796)', function(done) {
     const schema = new Schema({eggs: Number});
-    const M = db.model('Breakfast', schema);
+    const M = db.model('Test', schema);
 
     M.create({}, function(error, doc) {
       assert.ifError(error);
@@ -1285,7 +1288,7 @@ describe('model: update:', function() {
       band.post('update', function() {
         ++numPosts;
       });
-      const Band = db.model('gh-964', band);
+      const Band = db.model('Band', band);
 
       const gnr = new Band({members: ['Axl', 'Slash', 'Izzy', 'Duff', 'Adler']});
       gnr.save(function(error) {
@@ -1316,7 +1319,7 @@ describe('model: update:', function() {
       bandSchema.pre('update', function() {
         this.options.runValidators = true;
       });
-      const Band = db.model('gh2706', bandSchema, 'gh2706');
+      const Band = db.model('Band', bandSchema);
 
       Band.update({}, {$set: {lead: 'Not Axl'}}, function(err) {
         assert.ok(err);
@@ -1335,7 +1338,7 @@ describe('model: update:', function() {
         bandSchema.pre('update', function() {
           this.options.runValidators = true;
         });
-        const Band = db.model('gh2706', bandSchema, 'gh2706');
+        const Band = db.model('Band', bandSchema);
 
         Band.update({}, {$set: {singer: {firstName: 'Not', lastName: 'Axl'}}}, function(err) {
           assert.ok(err);
@@ -1349,7 +1352,7 @@ describe('model: update:', function() {
           role: {type: String, required: true, enum: ['singer', 'guitar', 'drums', 'bass']}
         });
         const band = new Schema({members: [member], name: String});
-        const Band = db.model('band', band, 'bands');
+        const Band = db.model('Band', band);
         const members = [
           {name: 'Axl Rose', role: 'singer'},
           {name: 'Slash', role: 'guitar'},
@@ -1375,7 +1378,7 @@ describe('model: update:', function() {
           return false;
         });
 
-        const M = db.model('gh3724', schema);
+        const M = db.model('Test', schema);
         const options = {runValidators: true};
         M.findOneAndUpdate({}, {arr: ['test']}, options, function(error) {
           assert.ok(error);
@@ -1396,7 +1399,7 @@ describe('model: update:', function() {
       author: String,
       id: Number
     };
-    const Book = db.model('gh2568', bookSchema);
+    const Book = db.model('Book', bookSchema);
 
     const jsonObject = {
       chapters: [{name: 'Ursus'}, {name: 'The Comprachicos'}],
@@ -1422,7 +1425,7 @@ describe('model: update:', function() {
     const dateSchema = {
       d: Date
     };
-    const D = db.model('gh2833', dateSchema);
+    const D = db.model('Test', dateSchema);
 
     assert.doesNotThrow(function() {
       D.update({}, {d: undefined}, function() {
@@ -1438,7 +1441,7 @@ describe('model: update:', function() {
       schema.pre('update', function() {
         this.set('updatedAt', date);
       });
-      const M = db.model('gh5770_0', schema);
+      const M = db.model('Test', schema);
 
       return M.update({}, { name: 'Test' }, { upsert: true }).
         then(() => M.findOne()).
@@ -1453,7 +1456,7 @@ describe('model: update:', function() {
       schema.pre('update', function() {
         this.set({ updatedAt: date });
       });
-      const M = db.model('gh5770_1', schema);
+      const M = db.model('Test', schema);
 
       return M.update({}, { name: 'Test' }, { upsert: true }).
         then(() => M.findOne()).
@@ -1471,7 +1474,7 @@ describe('model: update:', function() {
       return 'bar';
     });
 
-    const Parent = db.model('gh2046', parentSchema, 'gh2046');
+    const Parent = db.model('Parent', parentSchema);
 
     const update = Parent.update({}, {$push: {children: {foo: 'foo'}}}, {upsert: true});
     assert.equal(update._update.$push.children.bar, undefined);
@@ -1492,7 +1495,7 @@ describe('model: update:', function() {
       key: Number,
       value: String
     });
-    const Model = db.model('gh3008', FooSchema);
+    const Model = db.model('Test', FooSchema);
 
     const update = {$set: {values: 2, value: 2}};
     Model.update({key: 1}, update, function() {
@@ -1504,7 +1507,7 @@ describe('model: update:', function() {
   describe('bug fixes', function() {
     it('can $rename (gh-1845)', function(done) {
       const schema = new Schema({ foo: Date, bar: Date });
-      const Model = db.model('gh1845', schema, 'gh1845');
+      const Model = db.model('Test', schema);
 
       const update = { $rename: { foo: 'bar'} };
       Model.create({ foo: Date.now() }, function(error) {
@@ -1520,7 +1523,7 @@ describe('model: update:', function() {
 
     it('allows objects with positional operator (gh-3185)', function(done) {
       const schema = new Schema({children: [{_id: Number}]});
-      const MyModel = db.model('gh3185', schema, 'gh3185');
+      const MyModel = db.model('Test', schema);
 
       MyModel.create({children: [{_id: 1}]}, function(error, doc) {
         assert.ifError(error);
@@ -1538,7 +1541,7 @@ describe('model: update:', function() {
 
     it('mixed type casting (gh-3305)', function(done) {
       const Schema = mongoose.Schema({}, {strict: false});
-      const Model = db.model('gh3305', Schema);
+      const Model = db.model('Test', Schema);
 
       Model.create({}, function(error, m) {
         assert.ifError(error);
@@ -1556,7 +1559,7 @@ describe('model: update:', function() {
       const schema = mongoose.Schema({ name: String, age: Number }, {
         versionKey: false
       });
-      const Model = db.model('gh3998_r1', schema);
+      const Model = db.model('Test', schema);
 
       Model.create({ name: 'abc', age: 1 }, function(error, m) {
         assert.ifError(error);
@@ -1576,7 +1579,7 @@ describe('model: update:', function() {
 
     it('mixed nested type casting (gh-3337)', function(done) {
       const Schema = mongoose.Schema({attributes: {}}, {strict: true});
-      const Model = db.model('gh3337', Schema);
+      const Model = db.model('Test', Schema);
 
       Model.create({}, function(error, m) {
         assert.ifError(error);
@@ -1641,7 +1644,7 @@ describe('model: update:', function() {
         field2: SubdocSchema
       });
 
-      const Collection = db.model('gh4621', CollectionSchema);
+      const Collection = db.model('Test', CollectionSchema);
 
       Collection.create({}, function(error, doc) {
         assert.ifError(error);
@@ -1661,7 +1664,7 @@ describe('model: update:', function() {
 
     it('works with buffers (gh-3496)', function(done) {
       const Schema = mongoose.Schema({myBufferField: Buffer});
-      const Model = db.model('gh3496', Schema);
+      const Model = db.model('Test', Schema);
 
       Model.update({}, {myBufferField: Buffer.alloc(1)}, function(error) {
         assert.ifError(error);
@@ -1671,7 +1674,7 @@ describe('model: update:', function() {
 
     it('.update(doc) (gh-3221)', function() {
       const Schema = mongoose.Schema({name: String});
-      const Model = db.model('gh3221', Schema);
+      const Model = db.model('Test', Schema);
 
       let query = Model.update({name: 'Val'});
       assert.equal(query.getUpdate().name, 'Val');
@@ -1694,7 +1697,7 @@ describe('model: update:', function() {
         regions: [OrderSchema]
       }, { useNestedStrict: true });
 
-      const Season = db.model('gh3883', SeasonSchema);
+      const Season = db.model('Test', SeasonSchema);
       const obj = { regions: [{ r: 'test', action: { order: 'hold' } }] };
       Season.create(obj, function(error) {
         assert.ifError(error);
@@ -1717,7 +1720,7 @@ describe('model: update:', function() {
         next();
       });
 
-      const Model = db.model('gh3549', Schema);
+      const Model = db.model('Test', Schema);
 
       Model.create({}, function(error, doc) {
         assert.ifError(error);
@@ -1745,7 +1748,7 @@ describe('model: update:', function() {
         followers: [500]
       };
 
-      const M = db.model('gh-3564', schema);
+      const M = db.model('Test', schema);
 
       M.create(doc, function(err) {
         assert.ifError(err);
@@ -1774,7 +1777,7 @@ describe('model: update:', function() {
         infoList: { type: [InfoSchema] }
       });
 
-      const ModelA = db.model('gh3890', ModelASchema);
+      const ModelA = db.model('Test', ModelASchema);
 
       const propValue = Buffer.from('aa267824dc1796f265ab47870e279780', 'base64');
 
@@ -1795,7 +1798,7 @@ describe('model: update:', function() {
         name: Buffer
       };
 
-      const Model = db.model('gh3961', schema);
+      const Model = db.model('Test', schema);
 
       const value = Buffer.from('aa267824dc1796f265ab47870e279780', 'base64');
       const instance = new Model({ name: null });
@@ -1817,7 +1820,7 @@ describe('model: update:', function() {
         arr: [{ num: Number }]
       });
 
-      const Model = db.model('gh2593', schema);
+      const Model = db.model('Test', schema);
       const update = { $inc: { num: 1 }, $push: { arr: { num: 5 } } };
       const options = {
         upsert: true,
@@ -1837,7 +1840,7 @@ describe('model: update:', function() {
         tags: [String]
       }, { timestamps: true });
 
-      const Tag = db.model('gh4989', TagSchema);
+      const Tag = db.model('Test', TagSchema);
 
       return co(function*() {
         yield Tag.create({ name: 'test' });
@@ -1886,7 +1889,7 @@ describe('model: update:', function() {
         name: String
       }, { timestamps: true });
 
-      const Test = db.model('gh5222', testSchema);
+      const Test = db.model('Test', testSchema);
 
       Test.create({ name: 'test' }, function(error) {
         assert.ifError(error);
@@ -1915,7 +1918,7 @@ describe('model: update:', function() {
         }
       });
 
-      const Company = mongoose.model('Company', CompanySchema);
+      const Company = db.model('Company', CompanySchema);
 
       const update = {
         area: {
@@ -1953,7 +1956,7 @@ describe('model: update:', function() {
         children: [childSchema]
       }, opts);
 
-      const Parent = db.model('gh4049', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const b2 = new Parent();
       b2.save(function(err, doc) {
@@ -1991,7 +1994,7 @@ describe('model: update:', function() {
         child: childSchema
       }, opts);
 
-      const Parent = db.model('gh4049_0', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       const b2 = new Parent();
       b2.save(function(err, doc) {
@@ -2025,7 +2028,7 @@ describe('model: update:', function() {
         }]
       }, { timestamps: true });
 
-      const Model = db.model('gh4418', schema);
+      const Model = db.model('Test', schema);
       const query = { 'thing.thing2': 'test' };
       const update = { $set: { 'thing.$.test': 'test' } };
       Model.update(query, update, function(error) {
@@ -2041,7 +2044,7 @@ describe('model: update:', function() {
         }]
       }, { timestamps: true });
 
-      const sampleModel = db.model('gh4514', sampleSchema);
+      const sampleModel = db.model('Test', sampleSchema);
       const newRecord = new sampleModel({
         sampleArray: [{ values: ['record1'] }]
       });
@@ -2075,7 +2078,7 @@ describe('model: update:', function() {
         children: [childSchema]
       });
 
-      const Model = db.model('gh4953', parentSchema);
+      const Model = db.model('Test', parentSchema);
 
       const update = {
         $addToSet: { children: { name: 'Test' } }
@@ -2094,7 +2097,7 @@ describe('model: update:', function() {
         something: Number
       }, { timestamps: true });
 
-      const TestModel = db.model('gh4054', testSchema);
+      const TestModel = db.model('Test', testSchema);
       const options = { overwrite: true, upsert: true };
       const update = {
         user: 'John',
@@ -2120,7 +2123,7 @@ describe('model: update:', function() {
         arr: [arrSchema]
       });
 
-      const M = db.model('gh4609', schema);
+      const M = db.model('Test', schema);
 
       const m = new M({ arr: [{ ip: Buffer.alloc(1) }] });
       m.save(function(error, m) {
@@ -2135,7 +2138,7 @@ describe('model: update:', function() {
     it('update handles casting with mongoose-long (gh-4283)', function(done) {
       require('mongoose-long')(mongoose);
 
-      const Model = db.model('gh4283', {
+      const Model = db.model('Test', {
         number: { type: mongoose.Types.Long }
       });
 
@@ -2186,7 +2189,7 @@ describe('model: update:', function() {
         }]
       });
 
-      const User = db.model('gh4960', UserSchema);
+      const User = db.model('User', UserSchema);
 
       User.create({}).
         then(function(user) {
@@ -2214,7 +2217,7 @@ describe('model: update:', function() {
         geo: {type: [Number], index: '2dsphere'}
       }, { _id : false });
       const containerSchema = new Schema({ address: addressSchema });
-      const Container = db.model('gh4465', containerSchema);
+      const Container = db.model('Test', containerSchema);
 
       Container.update({}, { address: { geo: [-120.24, 39.21] } }).
         exec(function(error) {
@@ -2233,7 +2236,7 @@ describe('model: update:', function() {
 
       let B = new Schema({a: [A]});
 
-      B = db.model('b', B);
+      B = db.model('Test', B);
 
       B.findOneAndUpdate(
         {foo: 'bar'},
@@ -2266,7 +2269,7 @@ describe('model: update:', function() {
       });
 
 
-      const User = db.model('gh4655', UserSchema);
+      const User = db.model('User', UserSchema);
 
       User.create({ profiles: [] }, function(error, user) {
         assert.ifError(error);
@@ -2287,7 +2290,7 @@ describe('model: update:', function() {
         name: String,
         meta: { age: { type: Number } }
       });
-      const User = db.model('gh4749', schema);
+      const User = db.model('User', schema);
 
       const filter = { name: 'Bar' };
       const update = { name: 'Bar', meta: { age: 33 } };
@@ -2331,7 +2334,7 @@ describe('model: update:', function() {
         username: String,
         isDeleted: Boolean
       }, { timestamps: true });
-      const User = db.model('gh5045', schema);
+      const User = db.model('Test', schema);
 
       User.findOneAndUpdate(
         { username: 'test', isDeleted: false },
@@ -2366,7 +2369,7 @@ describe('model: update:', function() {
         }]
       });
 
-      const User = db.model('gh5041', UserSchema);
+      const User = db.model('User', UserSchema);
 
       User.findOneAndUpdate({}, { foos: [{ foo: '13.57' }] }, function(error) {
         assert.ifError(error);
@@ -2383,7 +2386,7 @@ describe('model: update:', function() {
         },
         otherName: String
       });
-      const Test = db.model('gh3556', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const opts = { overwrite: true, runValidators: true };
       Test.update({}, { otherName: 'test' }, opts, function(error) {
@@ -2401,7 +2404,7 @@ describe('model: update:', function() {
         username: String,
         x: String
       }, { timestamps: true });
-      const User = db.model('gh5088', schema);
+      const User = db.model('User', schema);
 
       User.create({ username: 'test' }).
         then(function(user) {
@@ -2420,7 +2423,7 @@ describe('model: update:', function() {
       const schema = new Schema({
         fieldOne: String
       }, { strict: true });
-      const Test = db.model('gh5111', schema);
+      const Test = db.model('Test', schema);
 
       Test.create({ fieldOne: 'Test' }).
         then(function() {
@@ -2448,7 +2451,7 @@ describe('model: update:', function() {
         name: String,
         arr: [{ name: String }]
       }, { strict: true });
-      const Test = db.model('gh5164', schema);
+      const Test = db.model('Test', schema);
 
       const doc = new Test({ name: 'Test', arr: [null, {name: 'abc'}] });
 
@@ -2472,7 +2475,7 @@ describe('model: update:', function() {
         colors: [{type: String}]
       });
 
-      const Model = db.model('gh5403', Schema);
+      const Model = db.model('Test', Schema);
 
       Model.create({ colors: ['green'] }).
         then(function() {
@@ -2497,7 +2500,7 @@ describe('model: update:', function() {
         nested: nestedSchema
       });
 
-      const Model = db.model('gh-7098', schema);
+      const Model = db.model('Test', schema);
 
       const test = new Model({
         xyz: [
@@ -2536,7 +2539,7 @@ describe('model: update:', function() {
         something: { type: Number, default: 2 }
       });
 
-      const TestModel = db.model('gh5384', testSchema);
+      const TestModel = db.model('Test', testSchema);
       const options = {
         overwrite: true,
         upsert: true,
@@ -2569,7 +2572,7 @@ describe('model: update:', function() {
         d: childSchema
       });
 
-      const Parent = db.model('gh5269', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
 
       Parent.update({}, { d: { d2: 'test' } }, { runValidators: true }, function(error) {
         assert.ok(error);
@@ -2586,7 +2589,7 @@ describe('model: update:', function() {
         data: String
       }, { timestamps: true });
 
-      const Model = db.model('gh5413', schema);
+      const Model = db.model('Test', schema);
 
       Model.
         where({ _id: 'test' }).
@@ -2604,13 +2607,13 @@ describe('model: update:', function() {
         message: String
       });
 
-      const Notification = db.model('gh5430_0', notificationSchema);
+      const Notification = db.model('Test', notificationSchema);
 
       const userSchema = new mongoose.Schema({
         notifications: [notificationSchema]
       });
 
-      const User = db.model('gh5430', userSchema);
+      const User = db.model('User', userSchema);
 
       User.update({}, {
         $push: {
@@ -2636,7 +2639,7 @@ describe('model: update:', function() {
         notifications: [notificationSchema]
       });
 
-      const User = db.model('gh5555', userSchema);
+      const User = db.model('User', userSchema);
 
       const opts = { multi: true, runValidators: true };
       const update = {
@@ -2672,7 +2675,7 @@ describe('model: update:', function() {
           name: String
         }]
       });
-      const ExampleModel = db.model('gh5744', exampleSchema);
+      const ExampleModel = db.model('Test', exampleSchema);
       const exampleDocument = {
         subdocuments: [{ name: 'First' }, { name: 'Second' }]
       };
@@ -2706,7 +2709,7 @@ describe('model: update:', function() {
         }
       });
 
-      const Item = db.model('gh6431', ItemSchema);
+      const Item = db.model('Test', ItemSchema);
 
       const opts = {
         runValidators: true,
@@ -2749,7 +2752,7 @@ describe('model: update:', function() {
           }]
         });
 
-        const Person = db.model('gh5361', schema);
+        const Person = db.model('Person', schema);
 
         const data = {
           name: 'Jack',
@@ -2779,7 +2782,7 @@ describe('model: update:', function() {
         date: { type: Date, required: true }
       }, { strict: true });
 
-      const Model = db.model('gh5453', schema);
+      const Model = db.model('Test', schema);
       const q = { notInSchema: true };
       const u = { $set: { smth: 1 } };
       const o = { strict: false, upsert: true };
@@ -2789,7 +2792,7 @@ describe('model: update:', function() {
     });
 
     it('replaceOne with buffer (gh-6124)', function() {
-      const SomeModel = db.model('gh6124', new Schema({
+      const SomeModel = db.model('Test', new Schema({
         name: String,
         binaryProp: Buffer
       }));
@@ -2813,7 +2816,7 @@ describe('model: update:', function() {
         name: String
       });
 
-      const Model = db.model('gh3677', schema);
+      const Model = db.model('Test', schema);
       Model.updateMany(['foo'], { name: 'bar' }, function(error) {
         assert.ok(error);
         assert.equal(error.name, 'ObjectParameterError');
@@ -2828,7 +2831,7 @@ describe('model: update:', function() {
         name: String
       });
 
-      const Model = db.model('gh5839', schema);
+      const Model = db.model('Test', schema);
 
       const opts = { upsert: 1 };
       Model.update({ name: 'Test' }, { name: 'Test2' }, opts, function(error) {
@@ -2846,7 +2849,7 @@ describe('model: update:', function() {
         numbers: [Number]
       });
 
-      const Model = db.model('gh6086', schema);
+      const Model = db.model('Test', schema);
 
       return Model.create({ numbers: [1, 2] }).
         then(function(doc) {
@@ -2868,7 +2871,7 @@ describe('model: update:', function() {
         arr: [[String]]
       });
 
-      const Test = db.model('gh6768', schema);
+      const Test = db.model('Test', schema);
 
       const test = new Test;
 
@@ -2900,7 +2903,7 @@ describe('model: update:', function() {
         const textSchema = new Schema({ text: String }, { _id: false });
         sectionArray.discriminator('text', textSchema);
 
-        const Site = db.model('gh5841', siteSchema);
+        const Site = db.model('Test', siteSchema);
 
         let doc = yield Site.create({
           sections: [
@@ -2929,7 +2932,7 @@ describe('model: update:', function() {
         strict: true
       });
 
-      const Test = db.model('gh5640', testSchema);
+      const Test = db.model('Test', testSchema);
 
       const doc = {
         _id: {
@@ -2955,7 +2958,7 @@ describe('model: update:', function() {
 
     it('$inc cast errors (gh-6770)', function() {
       const testSchema = new mongoose.Schema({ num: Number });
-      const Test = db.model('gh6770', testSchema);
+      const Test = db.model('Test', testSchema);
 
       return co(function*() {
         yield Test.create({ num: 1 });
@@ -2992,7 +2995,7 @@ describe('model: update:', function() {
         return this.total * 0.15;
       });
 
-      const Test = db.model('gh6731', schema);
+      const Test = db.model('Test', schema);
 
       // Shouldn't throw an error because `capitalGainsTax` is a virtual
       return Test.update({}, { total: 10000, capitalGainsTax: 1500 });
@@ -3003,7 +3006,7 @@ describe('model: update:', function() {
         name: String
       }, { strict: true });
 
-      const Model = db.model('gh5477', schema);
+      const Model = db.model('Test', schema);
       const q = { notAField: true };
       const u = { $set: { name: 'Test' } };
       const o = { upsert: true };
@@ -3072,7 +3075,7 @@ describe('model: update:', function() {
         arr: [sub]
       });
 
-      const Test = db.model('gh6532', schema);
+      const Test = db.model('Test', schema);
 
       const test = {
         name: 'Xyz',
@@ -3121,7 +3124,7 @@ describe('model: updateOne: ', function() {
       }
     });
 
-    const Test = db.model('gh7111', schema);
+    const Test = db.model('Test', schema);
 
     return co(function*() {
       const doc = yield Test.create({ accounts: { USD: { balance: 345 } } });
@@ -3139,7 +3142,7 @@ describe('model: updateOne: ', function() {
     }, { _id: false });
     const ArraySchema = Schema({ anArray: [ElementSchema] });
 
-    const TestModel = db.model('gh7135', ArraySchema);
+    const TestModel = db.model('Test', ArraySchema);
 
     return co(function*() {
       let err = yield TestModel.
@@ -3160,7 +3163,7 @@ describe('model: updateOne: ', function() {
   it('sets child timestamps even without $set (gh-7261)', function() {
     const childSchema = new Schema({ name: String }, { timestamps: true });
     const parentSchema = new Schema({ child: childSchema });
-    const Parent = db.model('gh7261', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
       yield Parent.create({ child: { name: 'Luke Skywalker' } });
@@ -3183,7 +3186,7 @@ describe('model: updateOne: ', function() {
       kind: { type: String, required: true }
     }, { discriminatorKey: 'kind' });
 
-    const Test = db.model('gh7843', testSchema);
+    const Test = db.model('Test', testSchema);
 
     const testSchemaChild = new mongoose.Schema({
       label: String
@@ -3209,7 +3212,7 @@ describe('model: updateOne: ', function() {
       name: String
     }, { timestamps: true });
 
-    const Model = db.model('gh7917', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.updateOne({}, { name: 'foo' }, { upsert: true });
@@ -3230,7 +3233,7 @@ describe('model: updateOne: ', function() {
       name: String
     }, { timestamps: true });
 
-    const Model = db.model('gh8001', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.updateOne({}, { test: 'before', name: 'foo' }, { upsert: true });
@@ -3248,7 +3251,7 @@ describe('model: updateOne: ', function() {
   });
 
   it('allow $pull with non-existent schema field (gh-8166)', function() {
-    const Model = db.model('gh8166', Schema({
+    const Model = db.model('Test', Schema({
       name: String,
       arr: [{
         status: String,
@@ -3291,7 +3294,7 @@ describe('model: updateOne: ', function() {
     slidesSchema.discriminator('typeA', new Schema({ a: String }));
     slidesSchema.discriminator('typeB', new Schema({ b: String }));
 
-    const MyModel = db.model('gh8063', schema);
+    const MyModel = db.model('Test', schema);
     return co(function*() {
       const doc = yield MyModel.create({
         slides: [{ type: 'typeA', a: 'oldValue1', commonField: 'oldValue2' }]
@@ -3315,7 +3318,7 @@ describe('model: updateOne: ', function() {
   });
 
   it('moves $set of immutable properties to $setOnInsert (gh-8467)', function() {
-    const Model = db.model('gh8467', Schema({
+    const Model = db.model('Test', Schema({
       name: String,
       age: { type: Number, default: 25, immutable: true }
     }));
@@ -3358,7 +3361,7 @@ describe('model: updateOne: ', function() {
 
     it('update pipeline (gh-8225)', function() {
       const schema = Schema({ oldProp: String, newProp: String });
-      const Model = db.model('gh8225', schema);
+      const Model = db.model('Test', schema);
 
       return co(function*() {
         yield Model.create({ oldProp: 'test' });
@@ -3382,7 +3385,7 @@ describe('model: updateOne: ', function() {
     });
 
     it('update pipeline timestamps (gh-8524)', function() {
-      const Cat = db.model('Cat', Schema({ name: String }, { timestamps: true }));
+      const Cat = db.model('Test', Schema({ name: String }, { timestamps: true }));
 
       return co(function*() {
         const cat = yield Cat.create({ name: 'Entei' });

From 3de8efa51dcb0e20621d111fd8bddbb3076e5226 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 29 Feb 2020 17:48:33 -0500
Subject: [PATCH 0547/2348] test: clean up test failures re: #8481 and refactor
 out clear collection logic

---
 test/document.test.js               | 14 ++------------
 test/model.findOneAndUpdate.test.js | 14 ++------------
 test/model.populate.test.js         | 14 ++------------
 test/model.querying.test.js         | 14 ++------------
 test/model.test.js                  | 14 ++------------
 test/model.update.test.js           | 21 ++++++---------------
 test/query.test.js                  | 14 ++------------
 test/util.js                        | 15 +++++++++++++++
 8 files changed, 33 insertions(+), 87 deletions(-)
 create mode 100644 test/util.js

diff --git a/test/document.test.js b/test/document.test.js
index ba33bf35022..22a38dff31a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -13,6 +13,7 @@ const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
+const util = require('./util');
 const utils = require('../lib/utils');
 const validator = require('validator');
 const Buffer = require('safe-buffer').Buffer;
@@ -134,18 +135,7 @@ describe('document', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(() => {
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   describe('constructor', function() {
     it('supports passing in schema directly (gh-8237)', function() {
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index a1a82faed07..719c1b03306 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -17,6 +17,7 @@ const DocumentObjectId = mongoose.Types.ObjectId;
 const co = require('co');
 const isEqual = require('lodash.isequal');
 const isEqualWith = require('lodash.isequalwith');
+const util = require('./util');
 const uuid = require('uuid');
 
 describe('model: findOneAndUpdate:', function() {
@@ -92,18 +93,7 @@ describe('model: findOneAndUpdate:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(() => {
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   it('WWW returns the edited document', function(done) {
     const M = db.model(modelname, collection);
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 9ad000da373..6425391fa6f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9,6 +9,7 @@ const start = require('./common');
 const assert = require('assert');
 const co = require('co');
 const utils = require('../lib/utils');
+const util = require('./util');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
@@ -68,18 +69,7 @@ describe('model: populate:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(() => {
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   it('populating array of object', function(done) {
     const BlogPost = db.model('BlogPost', blogPostSchema);
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 9a082810af8..139a298c535 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -10,6 +10,7 @@ const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
+const util = require('./util');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
@@ -30,18 +31,7 @@ describe('model: querying:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(() => {
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.test.js b/test/model.test.js
index 58b625d07dc..6b772613881 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -9,6 +9,7 @@ const start = require('./common');
 const assert = require('assert');
 const co = require('co');
 const random = require('../lib/utils').random;
+const util = require('./util');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
@@ -84,18 +85,7 @@ describe('Model', function() {
     db.close();
   });
 
-  afterEach(() => {
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   it('can be created using _id as embedded document', function(done) {
     const Test = db.model('Test', Schema({
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 9ca875ba848..59030017b99 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -8,7 +8,7 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
+const util = require('./util');
 const Buffer = require('safe-buffer').Buffer;
 
 const mongoose = start.mongoose;
@@ -17,7 +17,7 @@ const ObjectId = Schema.Types.ObjectId;
 const DocumentObjectId = mongoose.Types.ObjectId;
 const CastError = mongoose.Error.CastError;
 
-describe('model: update: XYZ', function() {
+describe('model: update:', function() {
   let post;
   const title = 'Tobi';
   const author = 'Brian';
@@ -103,19 +103,7 @@ describe('model: update: XYZ', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(function() {
-    this.timeout(5000);
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   it('works', function(done) {
     BlogPost.findById(post._id, function(err, cf) {
@@ -3114,6 +3102,9 @@ describe('model: updateOne: ', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => util.clearTestData(db));
+
   it('updating a map (gh-7111)', function() {
     const accountSchema = new Schema({ balance: Number });
 
diff --git a/test/query.test.js b/test/query.test.js
index f17c6aa57a0..58cafdb0d51 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -9,6 +9,7 @@ const start = require('./common');
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
+const util = require('./util');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -48,18 +49,7 @@ describe('Query', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
 
-  afterEach(() => {
-    const arr = [];
-
-    if (db.models == null) {
-      return;
-    }
-    for (const model of Object.keys(db.models)) {
-      arr.push(db.models[model].deleteMany({}));
-    }
-
-    return Promise.all(arr);
-  });
+  afterEach(() => util.clearTestData(db));
 
   describe('constructor', function() {
     it('should not corrupt options', function(done) {
diff --git a/test/util.js b/test/util.js
new file mode 100644
index 00000000000..91d92951dde
--- /dev/null
+++ b/test/util.js
@@ -0,0 +1,15 @@
+'use strict';
+
+exports.clearTestData = function clearTestData(db) {
+  if (db.models == null) {
+    return;
+  }
+
+  const arr = [];
+
+  for (const model of Object.keys(db.models)) {
+    arr.push(db.models[model].deleteMany({}));
+  }
+
+  return Promise.all(arr);
+};
\ No newline at end of file

From 4ca8b651729e417d079bd66fb411ca2a996f6348 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 29 Feb 2020 18:09:58 -0500
Subject: [PATCH 0548/2348] test: remove unnecessarily created collections from
 schema.test.js and types.array.test.js

Re: #8481
---
 test/schema.test.js      |  29 ++++----
 test/types.array.test.js | 148 ++++++++++++++++++---------------------
 2 files changed, 85 insertions(+), 92 deletions(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 3dd1639f062..d065f8ca282 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -54,6 +54,9 @@ describe('schema', function() {
     }));
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   describe('nested fields with same name', function() {
     let NestedModel;
 
@@ -67,7 +70,7 @@ describe('schema', function() {
         },
         b: { $type: String }
       }, { typeKey: '$type' });
-      NestedModel = db.model('Nested', NestedSchema);
+      NestedModel = db.model('Test', NestedSchema);
     });
 
     it('don\'t disappear', function(done) {
@@ -1247,9 +1250,8 @@ describe('schema', function() {
         }
       });
 
-      mongoose.model('Merged', MergedSchema);
-
-      const Merged = db.model('Merged', 'merged_' + Math.random());
+      db.deleteModel(/Test/);
+      const Merged = db.model('Test', MergedSchema);
 
       const merged = new Merged({
         a: {
@@ -1375,11 +1377,11 @@ describe('schema', function() {
       const el = new Schema({ title: String });
       const so = new Schema({
         title: String,
-        obj: { type: Schema.Types.ObjectId, ref: 'Element' }
+        obj: { type: Schema.Types.ObjectId, ref: 'Test' }
       });
 
-      const Element = db.model('Element', el);
-      const Some = db.model('Some', so);
+      const Element = db.model('Test', el);
+      const Some = db.model('Test1', so);
 
       const ele = new Element({ title: 'thing' });
 
@@ -1497,10 +1499,9 @@ describe('schema', function() {
 
     it('permit _scope to be used (gh-1184)', function(done) {
       const child = new Schema({ _scope: Schema.ObjectId });
-      const C = db.model('scope', child);
+      const C = db.model('Test', child);
       const c = new C;
       c.save(function(err) {
-        db.close();
         assert.ifError(err);
         try {
           c._scope;
@@ -1859,7 +1860,7 @@ describe('schema', function() {
             this.set('name.last', split[1]);
           });
 
-        const M = db.model('gh6274', PersonSchema.clone());
+        const M = db.model('Test', PersonSchema.clone());
 
         const doc = new M({ name: { first: 'Axl', last: 'Rose' } });
         assert.equal(doc.name.full, 'Axl Rose');
@@ -1881,7 +1882,7 @@ describe('schema', function() {
           _id: false,
           id: false
         });
-        const M = db.model('gh6274_option', clone);
+        const M = db.model('Test', clone);
 
         const doc = new M({});
 
@@ -1949,7 +1950,7 @@ describe('schema', function() {
         schema.path('fruits').discriminator('banana', clone);
         assert.ok(clone.path('color').caster.discriminators);
 
-        const Basket = db.model('gh7894', schema);
+        const Basket = db.model('Test', schema);
         const b = new Basket({
           fruits: [
             {
@@ -2120,7 +2121,7 @@ describe('schema', function() {
 
   it('required paths with clone() (gh-8111)', function() {
     const schema = Schema({ field: { type: String, required: true } });
-    const Model = db.model('gh8111', schema.clone());
+    const Model = db.model('Test', schema.clone());
 
     const doc = new Model({});
 
@@ -2137,7 +2138,7 @@ describe('schema', function() {
 
     schema.path('field').set(value => value ? value.toUpperCase() : value);
 
-    const TestKo = db.model('gh8124', schema.clone());
+    const TestKo = db.model('Test', schema.clone());
 
     const testKo = new TestKo({field: 'upper'});
     assert.equal(testKo.field, 'UPPER');
diff --git a/test/types.array.test.js b/test/types.array.test.js
index 4e5ae89dced..ea77f3ddd20 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -15,30 +15,25 @@ const random = require('../lib/utils').random;
 
 const MongooseArray = mongoose.Types.Array;
 const Schema = mongoose.Schema;
-const collection = 'avengers_' + random();
 
 /**
  * Test.
  */
 
 describe('types array', function() {
-  let User;
-  let Pet;
+  let UserSchema;
+  let PetSchema;
   let db;
 
   before(function() {
-    User = new Schema({
+    UserSchema = new Schema({
       name: String,
       pets: [Schema.ObjectId]
     });
 
-    mongoose.model('User', User);
-
-    Pet = new Schema({
+    PetSchema = new Schema({
       name: String
     });
-
-    mongoose.model('Pet', Pet);
     db = start();
   });
 
@@ -46,6 +41,9 @@ describe('types array', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('behaves and quacks like an Array', function(done) {
     const a = new MongooseArray;
 
@@ -58,7 +56,7 @@ describe('types array', function() {
   });
 
   it('is `deepEqual()` another array (gh-7700)', function(done) {
-    const Test = db.model('gh7700', new Schema({ arr: [String] }));
+    const Test = db.model('Test', new Schema({ arr: [String] }));
     const doc = new Test({ arr: ['test'] });
 
     assert.deepEqual(doc.arr, new MongooseArray(['test']));
@@ -94,8 +92,8 @@ describe('types array', function() {
 
   describe('indexOf()', function() {
     it('works', function(done) {
-      const User = db.model('User', 'users_' + random());
-      const Pet = db.model('Pet', 'pets' + random());
+      const User = db.model('User', UserSchema);
+      const Pet = db.model('Pet', PetSchema);
 
       const tj = new User({name: 'tj'});
       const tobi = new Pet({name: 'tobi'});
@@ -138,8 +136,8 @@ describe('types array', function() {
 
   describe('includes()', function() {
     it('works', function(done) {
-      const User = db.model('User', 'users_' + random());
-      const Pet = db.model('Pet', 'pets' + random());
+      const User = db.model('User', UserSchema);
+      const Pet = db.model('Pet', PetSchema);
 
       const tj = new User({name: 'tj'});
       const tobi = new Pet({name: 'tobi'});
@@ -180,8 +178,6 @@ describe('types array', function() {
   });
 
   describe('push()', function() {
-    let N, S, B, M, D, ST;
-
     function save(doc, cb) {
       doc.save(function(err) {
         if (err) {
@@ -192,22 +188,8 @@ describe('types array', function() {
       });
     }
 
-    before(function(done) {
-      N = db.model('arraySet', Schema({arr: [Number]}));
-      S = db.model('arraySetString', Schema({arr: [String]}));
-      B = db.model('arraySetBuffer', Schema({arr: [Buffer]}));
-      M = db.model('arraySetMixed', Schema({arr: []}));
-      D = db.model('arraySetSubDocs', Schema({arr: [{name: String}]}));
-      ST = db.model('arrayWithSetters', Schema({
-        arr: [{
-          type: String,
-          lowercase: true
-        }]
-      }));
-      done();
-    });
-
     it('works with numbers', function(done) {
+      const N = db.model('Test', Schema({arr: [Number]}));
       const m = new N({arr: [3, 4, 5, 6]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -231,6 +213,7 @@ describe('types array', function() {
     });
 
     it('works with strings', function(done) {
+      const S = db.model('Test', Schema({arr: [String]}));
       const m = new S({arr: [3, 4, 5, 6]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -254,6 +237,7 @@ describe('types array', function() {
     });
 
     it('works with buffers', function(done) {
+      const B = db.model('Test', Schema({arr: [Buffer]}));
       const m = new B({arr: [[0], Buffer.alloc(1)]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -279,6 +263,8 @@ describe('types array', function() {
     });
 
     it('works with mixed', function(done) {
+      const M = db.model('Test', Schema({arr: []}));
+
       const m = new M({arr: [3, {x: 1}, 'yes', [5]]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -326,6 +312,8 @@ describe('types array', function() {
     });
 
     it('works with sub-docs', function(done) {
+      const D = db.model('Test', Schema({arr: [{name: String}]}));
+
       const m = new D({arr: [{name: 'aaron'}, {name: 'moombahton '}]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -349,6 +337,13 @@ describe('types array', function() {
     });
 
     it('applies setters (gh-3032)', function(done) {
+      const ST = db.model('Test', Schema({
+        arr: [{
+          type: String,
+          lowercase: true
+        }]
+      }));
+
       const m = new ST({arr: ['ONE', 'TWO']});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -373,9 +368,8 @@ describe('types array', function() {
 
   describe('splice()', function() {
     it('works', function(done) {
-      const collection = 'splicetest-number' + random();
       const schema = new Schema({numbers: [Number]});
-      const A = db.model('splicetestNumber', schema, collection);
+      const A = db.model('Test', schema);
 
       const a = new A({numbers: [4, 5, 6, 7]});
       a.save(function(err) {
@@ -403,9 +397,8 @@ describe('types array', function() {
     });
 
     it('on embedded docs', function(done) {
-      const collection = 'splicetest-embeddeddocs' + random();
       const schema = new Schema({types: [new Schema({type: String})]});
-      const A = db.model('splicetestEmbeddedDoc', schema, collection);
+      const A = db.model('Test', schema);
 
       const a = new A({types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}]});
       a.save(function(err) {
@@ -446,7 +439,7 @@ describe('types array', function() {
         nums: [Number],
         strs: [String]
       });
-      const A = db.model('unshift', schema, 'unshift' + random());
+      const A = db.model('Test', schema);
 
       const a = new A({
         types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}],
@@ -520,7 +513,7 @@ describe('types array', function() {
     });
 
     it('applies setters (gh-3032)', function(done) {
-      const ST = db.model('setterArrayUnshift', Schema({
+      const ST = db.model('Test', Schema({
         arr: [{
           type: String,
           lowercase: true
@@ -556,7 +549,7 @@ describe('types array', function() {
         strs: [String]
       });
 
-      const A = db.model('shift', schema, 'unshift' + random());
+      const A = db.model('Test', schema);
 
       const a = new A({
         types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}],
@@ -622,7 +615,7 @@ describe('types array', function() {
     it('works', function(done) {
       // atomic shift uses $pop -1
       const painting = new Schema({colors: []});
-      const Painting = db.model('PaintingShift', painting);
+      const Painting = db.model('Test', painting);
       const p = new Painting({colors: ['blue', 'green', 'yellow']});
       p.save(function(err) {
         assert.ifError(err);
@@ -666,7 +659,7 @@ describe('types array', function() {
         strs: [String]
       });
 
-      const A = db.model('pop', schema, 'pop' + random());
+      const A = db.model('Test', schema);
 
       const a = new A({
         types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}],
@@ -735,7 +728,7 @@ describe('types array', function() {
       const schema = new Schema({
         a: [{type: Schema.ObjectId, ref: 'Cat'}]
       });
-      const A = db.model('TestPull', schema);
+      const A = db.model('Test', schema);
       const cat = new Cat({name: 'peanut'});
       cat.save(function(err) {
         assert.ifError(err);
@@ -765,7 +758,7 @@ describe('types array', function() {
         members: [personSchema]
       });
 
-      const Band = db.model('gh3341', bandSchema, 'gh3341');
+      const Band = db.model('Test', bandSchema);
 
       const gnr = new Band({
         name: 'Guns N\' Roses',
@@ -803,7 +796,7 @@ describe('types array', function() {
 
     it('properly works with undefined', function(done) {
       const catschema = new Schema({ name: String, colors: [{hex: String}] });
-      const Cat = db.model('ColoredCat', catschema);
+      const Cat = db.model('Test', catschema);
 
       const cat = new Cat({name: 'peanut', colors: [
         {hex: '#FFF'}, {hex: '#000'}, null
@@ -835,7 +828,7 @@ describe('types array', function() {
   describe('$pop()', function() {
     it('works', function(done) {
       const painting = new Schema({colors: []});
-      const Painting = db.model('Painting', painting);
+      const Painting = db.model('Test', painting);
       const p = new Painting({colors: ['blue', 'green', 'yellow']});
       p.save(function(err) {
         assert.ifError(err);
@@ -883,7 +876,7 @@ describe('types array', function() {
         id: [Schema.ObjectId]
       });
 
-      const M = db.model('testAddToSet', schema);
+      const M = db.model('Test', schema);
       const m = new M;
 
       m.num.push(1, 2, 3);
@@ -1115,7 +1108,7 @@ describe('types array', function() {
         doc: [e]
       });
 
-      const M = db.model('gh1973', schema);
+      const M = db.model('Test', schema);
       const m = new M;
 
       m.doc.addToSet({name: 'Rap'});
@@ -1140,7 +1133,7 @@ describe('types array', function() {
     });
 
     it('applies setters (gh-3032)', function(done) {
-      const ST = db.model('setterArray', Schema({
+      const ST = db.model('Test', Schema({
         arr: [{
           type: String,
           lowercase: true
@@ -1187,7 +1180,7 @@ describe('types array', function() {
 
     it('castNonArrays (gh-7371) (gh-7479)', function() {
       const schema = new Schema({ arr: [String], docArr: [{ name: String }] });
-      const Model = db.model('gh7371', schema);
+      const Model = db.model('Test', schema);
 
       let doc = new Model({ arr: 'fail', docArr: { name: 'fail' } });
       assert.ok(doc.validateSync().errors);
@@ -1208,7 +1201,7 @@ describe('types array', function() {
         const schema = new Schema({
           arr: [mongoose.Schema.Types.ObjectId]
         });
-        const Model = db.model('gh7479', schema);
+        const Model = db.model('Test', schema);
         yield Model.create({ arr: [] });
 
         const oid = new mongoose.Types.ObjectId();
@@ -1229,7 +1222,7 @@ describe('types array', function() {
 
   describe('nonAtomicPush()', function() {
     it('works', function(done) {
-      const U = db.model('User');
+      const U = db.model('User', UserSchema);
       const ID = mongoose.Types.ObjectId;
 
       const u = new U({name: 'banana', pets: [new ID]});
@@ -1266,7 +1259,7 @@ describe('types array', function() {
 
   describe('sort()', function() {
     it('order should be saved', function(done) {
-      const M = db.model('ArraySortOrder', new Schema({x: [Number]}));
+      const M = db.model('Test', new Schema({x: [Number]}));
       const m = new M({x: [1, 4, 3, 2]});
       m.save(function(err) {
         assert.ifError(err);
@@ -1314,8 +1307,6 @@ describe('types array', function() {
   });
 
   describe('set()', function() {
-    let N, S, B, M, D, ST;
-
     function save(doc, cb) {
       doc.save(function(err) {
         if (err) {
@@ -1326,22 +1317,9 @@ describe('types array', function() {
       });
     }
 
-    before(function(done) {
-      N = db.model('arraySet2', Schema({arr: [Number]}));
-      S = db.model('arraySetString2', Schema({arr: [String]}));
-      B = db.model('arraySetBuffer2', Schema({arr: [Buffer]}));
-      M = db.model('arraySetMixed2', Schema({arr: []}));
-      D = db.model('arraySetSubDocs2', Schema({arr: [{name: String}]}));
-      ST = db.model('arrayWithSetters2', Schema({
-        arr: [{
-          type: String,
-          lowercase: true
-        }]
-      }));
-      done();
-    });
-
     it('works combined with other ops', function(done) {
+      const N = db.model('Test', Schema({arr: [Number]}));
+
       const m = new N({arr: [3, 4, 5, 6]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1385,11 +1363,11 @@ describe('types array', function() {
           });
         });
       });
-
-      // after this works go back to finishing doc.populate() branch
     });
 
     it('works with numbers', function(done) {
+      const N = db.model('Test', Schema({arr: [Number]}));
+
       const m = new N({arr: [3, 4, 5, 6]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1436,6 +1414,8 @@ describe('types array', function() {
     });
 
     it('works with strings', function(done) {
+      const S = db.model('Test', Schema({arr: [String]}));
+
       const m = new S({arr: [3, 4, 5, 6]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1482,6 +1462,8 @@ describe('types array', function() {
     });
 
     it('works with buffers', function(done) {
+      const B = db.model('Test', Schema({arr: [Buffer]}));
+
       const m = new B({arr: [[0], Buffer.alloc(1)]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1511,6 +1493,8 @@ describe('types array', function() {
     });
 
     it('works with mixed', function(done) {
+      const M = db.model('Test', Schema({arr: []}));
+
       const m = new M({arr: [3, {x: 1}, 'yes', [5]]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1566,6 +1550,8 @@ describe('types array', function() {
     });
 
     it('works with sub-docs', function(done) {
+      const D = db.model('Test', Schema({arr: [{name: String}]}));
+
       const m = new D({arr: [{name: 'aaron'}, {name: 'moombahton '}]});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1628,6 +1614,13 @@ describe('types array', function() {
     });
 
     it('applies setters (gh-3032)', function(done) {
+      const ST = db.model('Test', Schema({
+        arr: [{
+          type: String,
+          lowercase: true
+        }]
+      }));
+
       const m = new ST({arr: ['ONE', 'TWO']});
       save(m, function(err, doc) {
         assert.ifError(err);
@@ -1669,7 +1662,7 @@ describe('types array', function() {
 
   describe('setting a doc array', function() {
     it('should adjust path positions', function(done) {
-      const D = db.model('subDocPositions', new Schema({
+      const D = db.model('Test', new Schema({
         em1: [new Schema({name: String})]
       }));
 
@@ -1710,7 +1703,7 @@ describe('types array', function() {
 
   describe('paths with similar names', function() {
     it('should be saved', function(done) {
-      const D = db.model('similarPathNames', new Schema({
+      const D = db.model('Test', new Schema({
         account: {
           role: String,
           roles: [String]
@@ -1754,7 +1747,7 @@ describe('types array', function() {
   describe('of number', function() {
     it('allows nulls', function(done) {
       const schema = new Schema({x: [Number]}, {collection: 'nullsareallowed' + random()});
-      const M = db.model('nullsareallowed', schema);
+      const M = db.model('Test', schema);
       let m;
 
       m = new M({x: [1, null, 3]});
@@ -1774,7 +1767,7 @@ describe('types array', function() {
   describe('bug fixes', function() {
     it('modifying subdoc props and manipulating the array works (gh-842)', function(done) {
       const schema = new Schema({em: [new Schema({username: String})]});
-      const M = db.model('modifyingSubDocAndPushing', schema);
+      const M = db.model('Test', schema);
       const m = new M({em: [{username: 'Arrietty'}]});
 
       m.save(function(err) {
@@ -1814,7 +1807,7 @@ describe('types array', function() {
 
     it('pushing top level arrays and subarrays works (gh-1073)', function(done) {
       const schema = new Schema({em: [new Schema({sub: [String]})]});
-      const M = db.model('gh1073', schema);
+      const M = db.model('Test', schema);
       const m = new M({em: [{sub: []}]});
       m.save(function() {
         M.findById(m, function(err, m) {
@@ -1851,7 +1844,7 @@ describe('types array', function() {
         subs: [sub]
       });
 
-      const Model = db.model('gh4011', main);
+      const Model = db.model('Test', main);
 
       const doc = new Model({ subs: [{ _id: '57067021ee0870440c76f489' }] });
 
@@ -1868,8 +1861,7 @@ describe('types array', function() {
         num2: []
       });
 
-      mongoose.model('DefaultArraySchema', DefaultArraySchema);
-      const DefaultArray = db.model('DefaultArraySchema', collection);
+      const DefaultArray = db.model('Test', DefaultArraySchema);
       const arr = new DefaultArray();
 
       assert.equal(arr.get('num1').length, 0);

From 77de88bbd0cc6f959821973e2ec004c50f7a0620 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Mar 2020 15:46:53 -0500
Subject: [PATCH 0549/2348] chore: release 5.9.3

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9cefb45fae0..4ac2051b24c 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.9.3 / 2020-03-02
+==================
+ * fix: upgrade mongodb driver -> 3.5.4 #8620
+ * fix(document): set subpath defaults when overwriting single nested subdoc #8603
+ * fix(document): make calling `validate()` with single nested subpath only validate that single nested subpath #8626
+ * fix(browser): make `mongoose.model()` return a class in the browser to allow hydrating populated data in the browser #8605
+ * fix(model): make `syncIndexes()` and `cleanIndexes()` drop compound indexes with `_id` that aren't in the schema #8559
+ * docs(connection+index): add warnings to explain that bufferMaxEntries does nothing with `useUnifiedTopology` #8604
+ * docs(document+model+query): add `options.timestamps` parameter docs to `findOneAndUpdate()` and `findByIdAndUpdate()` #8619
+ * docs: fix out of date links to tumblr #8599
+
 5.9.2 / 2020-02-21
 ==================
  * fix(model): add discriminator key to bulkWrite filters #8590
diff --git a/package.json b/package.json
index 2096ed9a219..2fbb4ccef80 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.2",
+  "version": "5.9.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From fd29738eaee4b95fb488aa3e9071ef2c71d14fc9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Mar 2020 16:40:06 -0500
Subject: [PATCH 0550/2348] chore: update opencollective sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index f30149a9008..643ab93cc43 100644
--- a/index.pug
+++ b/index.pug
@@ -268,18 +268,12 @@ html(lang='en')
               <a href="https://www.crosswordsolver.com/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/crosswordsolver.png" style="height: 80px">
               </a>
-              <a href="https://uk.edubirdie.com/">
-                <img class="sponsor" src="https://images.opencollective.com/uk-edubirdie-com/b1d51ab/logo.png" style="height: 100px">
-              </a>
               <a href="https://www.monetta.pl/">
                 <img class="sponsor" src="https://images.opencollective.com/monetta/7d65ae6/logo.png" style="height: 100px">
               </a>
               <a href="https://www.minitool.com/">
                 <img class="sponsor" src="https://images.opencollective.com/minitool-solution-ltd/1519aa6/logo.png" style="height: 100px">
               </a>
-              <a href="https://synapsesearch.nz/">
-                <img class="sponsor" src="https://images.opencollective.com/synapsesearch/9f0bc41/logo.png" style="height: 100px">
-              </a>
               <a href="https://maaltidskasser.net/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/maaltidskasser-logo.png" style="height: 100px" alt="Måltidskasser">
               </a>

From 0bc4aa70e62881720289e40911a5eaf3b63670fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 3 Mar 2020 15:11:23 -0600
Subject: [PATCH 0551/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 643ab93cc43..8d30fa1a3b7 100644
--- a/index.pug
+++ b/index.pug
@@ -286,6 +286,9 @@ html(lang='en')
               <a href="https://unscramblex.com/">
                 <img class="sponsor" src="https://images.opencollective.com/unscramblex/87d6a68/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.nettikasinot.org/">
+                <img class="sponsor" src="https://images.opencollective.com/nettikasinot-org/bbd887f/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From db224226d6bc3f0b889fc24bcb11fd54fdc1a8dd Mon Sep 17 00:00:00 2001
From: Saurav Gupta <sonugupta34@gmail.com>
Date: Fri, 6 Mar 2020 00:13:41 +0530
Subject: [PATCH 0552/2348] Fix typo

---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index a0a962609a8..1c13f251e8c 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -80,7 +80,7 @@ block content
     and the branches do not have actual paths.  A side-effect of this is that `meta`
     above cannot have its own validation.  If validation is needed up the tree, a path
     needs to be created up the tree - see the [Subdocuments](./subdocs.html) section
-    for more information no how to do this.  Also read the [Mixed](./schematypes.html)
+    for more information on how to do this.  Also read the [Mixed](./schematypes.html)
     subsection of the SchemaTypes guide for some gotchas.
 
     The permitted SchemaTypes are:

From 8ad50c6fc034d132ef3acdea4c9810b0bd39d51b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Mar 2020 15:12:53 -0600
Subject: [PATCH 0553/2348] docs: clean up mobile layout for built with
 mongoose page

---
 docs/built-with-mongoose.pug | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
index 8c446bf65d9..9a21901d80c 100644
--- a/docs/built-with-mongoose.pug
+++ b/docs/built-with-mongoose.pug
@@ -8,13 +8,13 @@ block content
     over 870,000 projects that depend on Mongoose. Here are a few of
     our favorite apps that are built with Mongoose.
 
-    <div style="position: relative; height: 100px">
+    <div style="position: relative">
       <div style="position: absolute; width: 100px; height: 100px">
         <a href="https://sixplus.com">
           <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1452784634/wipgioqzev0omt4ezsay.jpg">
         </a>
       </div>
-      <div style="position: absolute; left: 110px">
+      <div style="padding-left: 110px; min-height: 100px;">
         <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://sixplus.com/">SixPlus</a></h3>
         SixPlus is an online marketplace for corporate event professionals to
         book private dining spaces in restaurants and hotels across the US.
@@ -23,26 +23,26 @@ block content
       </div>
     </div>
 
-    <div style="position: relative; height: 100px; margin-top: 1em;">
+    <div style="position: relative; margin-top: 1em;">
       <div style="position: absolute; width: 100px; height: 100px">
         <a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
           <img src="https://res-1.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1503059272/h8tzm8hqqabjknhj9cts.png">
         </a>
       </div>
-      <div style="position: absolute; left: 110px">
+      <div style="padding-left: 110px; min-height: 100px">
         <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">Payment Ninja</a></h3>
         Payment Ninja is an online payment gateway that lets you save up to
         50% on payment processing over processors like PayPal and Stripe.
       </div>
     </div>
 
-    <div style="position: relative; height: 100px; margin-top: 1em;">
+    <div style="position: relative; margin-top: 1em;">
       <div style="position: absolute; width: 100px; height: 100px">
         <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
           <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1426108234/rb6qztygayubxme8f4tx.png">
         </a>
       </div>
-      <div style="position: absolute; left: 110px">
+      <div style="padding-left: 110px; min-height: 100px">
         <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">Mixmax</a></h3>
         Mixmax is a app that sends engaging emails with instant scheduling, free unlimited email tracking, polls, and surveys right in Gmail.
       </div>
@@ -51,4 +51,4 @@ block content
     ## Add Your Own
 
     Have an app that you built with Mongoose that you want to feature here?
-    Let's talk! [DM Mongoose on Twitter](https://twitter.com/mongoosejs).
\ No newline at end of file
+    Let's talk! [DM Mongoose on Twitter](https://twitter.com/mongoosejs).

From 96669247ff9d0164c860aaf849e3399d78255c97 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Mar 2020 09:53:28 -0600
Subject: [PATCH 0554/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 8d30fa1a3b7..71f83e3d36c 100644
--- a/index.pug
+++ b/index.pug
@@ -289,6 +289,9 @@ html(lang='en')
               <a href="https://www.nettikasinot.org/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-org/bbd887f/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.pelisivut.com/">
+                <img class="sponsor" src="https://images.opencollective.com/pelisivut/04f08f2/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 059825b95c6ebee11364c79a4c844256c6721c75 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Mar 2020 11:54:35 -0600
Subject: [PATCH 0555/2348] docs(virtualtype+populate): document using `match`
 with virtual populate

Fix #8616
---
 docs/populate.pug  | 30 ++++++++++++++++++++++++++++++
 lib/virtualtype.js |  5 +++++
 2 files changed, 35 insertions(+)

diff --git a/docs/populate.pug b/docs/populate.pug
index b7ffba4c647..1951402697d 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -576,6 +576,36 @@ block content
     });
     ```
 
+    You can also use [the populate `match` option](http://thecodebarbarian.com/mongoose-5-5-static-hooks-and-populate-match-functions.html#populate-match-function)
+    to add an additional filter to the `populate()` query. This is useful
+    if you need to split up `populate()` data:
+
+    ```javascript
+    const PersonSchema = new Schema({
+      name: String,
+      band: String,
+      isActive: Boolean
+    });
+
+    const BandSchema = new Schema({
+      name: String
+    });
+    BandSchema.virtual('activeMembers', {
+      ref: 'Person',
+      localField: 'name',
+      foreignField: 'band',
+      justOne: false,
+      match: { isActive: true }
+    });
+    BandSchema.virtual('formerMembers', {
+      ref: 'Person',
+      localField: 'name',
+      foreignField: 'band',
+      justOne: false,
+      match: { isActive: false }
+    });
+    ```
+
     Keep in mind that virtuals are _not_ included in `toJSON()` output by default. If you want populate virtuals to show up when using functions
     that rely on `JSON.stringify()`, like Express'
     [`res.json()` function](http://expressjs.com/en/4x/api.html#res.json),
diff --git a/lib/virtualtype.js b/lib/virtualtype.js
index abac5f36ae1..f91438ac22d 100644
--- a/lib/virtualtype.js
+++ b/lib/virtualtype.js
@@ -17,6 +17,11 @@
  * @param {boolean} [options.justOne=false] by default, a populated virtual is an array. If you set `justOne`, the populated virtual will be a single doc or `null`.
  * @param {boolean} [options.getters=false] if you set this to `true`, Mongoose will call any custom getters you defined on this virtual
  * @param {boolean} [options.count=false] if you set this to `true`, `populate()` will set this virtual to the number of populated documents, as opposed to the documents themselves, using [`Query#countDocuments()`](./api.html#query_Query-countDocuments)
+ * @param {Object|Function} [options.match=null] add an extra match condition to `populate()`
+ * @param {Number} [options.limit=null] add a default `limit` to the `populate()` query
+ * @param {Number} [options.skip=null] add a default `skip` to the `populate()` query
+ * @param {Number} [options.perDocumentLimit=null] For legacy reasons, `limit` with `populate()` may give incorrect results because it only executes a single query for every document being populated. If you set `perDocumentLimit`, Mongoose will ensure correct `limit` per document by executing a separate query for each document to `populate()`. For example, `.find().populate({ path: 'test', perDocumentLimit: 2 })` will execute 2 additional queries if `.find()` returns 2 documents.
+ * @param {Object} [options.options=null] Additional options like `limit` and `lean`.
  * @api public
  */
 

From 63fe55d4dc131a90dd4e48f5bb2caad1961cb6ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Mar 2020 20:02:44 -0600
Subject: [PATCH 0556/2348] test(schema): repro #8627

---
 .../types.embeddeddocumentdeclarative.test.js | 21 ++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
index 092c52e72de..8b598555e82 100644
--- a/test/types.embeddeddocumentdeclarative.test.js
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -16,14 +16,12 @@ const Schema = mongoose.Schema;
 
 describe('types.embeddeddocumentdeclarative', function() {
   describe('with a parent with a field with type set to a POJO', function() {
-    const ChildSchemaDef = {
-      name: String,
-    };
-
     const ParentSchemaDef = {
       name: String,
       child: {
-        type: ChildSchemaDef,
+        type: {
+          name: String
+        }
       }
     };
 
@@ -71,6 +69,19 @@ describe('types.embeddeddocumentdeclarative', function() {
         assert.strictEqual(princessZelda.mixedUp, undefined);
         done();
       });
+
+      it('underneath array (gh-8627)', function() {
+        const schema = new Schema({
+          arr: [{
+            nested: {
+              type: { test: String }
+            }
+          }]
+        }, { typePojoToMixed: false });
+
+        assert.ok(schema.path('arr').schema.path('nested').instance !== 'Mixed');
+        assert.ok(schema.path('arr').schema.path('nested.test') instanceof mongoose.Schema.Types.String);
+      });
     });
   });
   describe('with a parent with a POJO field with a field "type" with a type set to "String"', function() {

From 1cd05dda4a0770e8c4ed121407d75754eb3ad4ff Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Mar 2020 20:03:01 -0600
Subject: [PATCH 0557/2348] fix(schema): propagate `typePojoToMixed` to
 implicitly created arrays

Fix #8627
---
 lib/schema.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index 03407386fc3..f2e48bf0371 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -928,6 +928,9 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         if (options.hasOwnProperty('strict')) {
           childSchemaOptions.strict = options.strict;
         }
+        if (options.hasOwnProperty('typePojoToMixed')) {
+          childSchemaOptions.typePojoToMixed = options.typePojoToMixed;
+        }
         const childSchema = new Schema(cast, childSchemaOptions);
         childSchema.$implicitlyCreated = true;
         return new MongooseTypes.DocumentArray(path, childSchema, obj);

From b4b61d312b57af710df33853311d12fb00075f08 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Mar 2020 20:06:55 -0600
Subject: [PATCH 0558/2348] fix(schema): also propagate `typePojoToMixed`
 option to schemas implicitly created because of `typePojoToMixed`

Fix #8627
---
 lib/schema.js                                  |  5 ++++-
 test/types.embeddeddocumentdeclarative.test.js | 17 +++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index f2e48bf0371..77718b0b9e2 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -507,7 +507,10 @@ Schema.prototype.add = function add(obj, prefix) {
         if (prefix) {
           this.nested[prefix.substr(0, prefix.length - 1)] = true;
         }
-        const schemaWrappedPath = Object.assign({}, obj[key], { type: new Schema(obj[key][this.options.typeKey]) });
+        // Propage `typePojoToMixed` to implicitly created schemas
+        const opts = { typePojoToMixed: false };
+        const _schema = new Schema(obj[key][this.options.typeKey], opts);
+        const schemaWrappedPath = Object.assign({}, obj[key], { type: _schema });
         this.path(prefix + key, schemaWrappedPath);
       } else {
         // Either the type is non-POJO or we interpret it as Mixed anyway
diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
index 8b598555e82..9f520208bba 100644
--- a/test/types.embeddeddocumentdeclarative.test.js
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -82,6 +82,23 @@ describe('types.embeddeddocumentdeclarative', function() {
         assert.ok(schema.path('arr').schema.path('nested').instance !== 'Mixed');
         assert.ok(schema.path('arr').schema.path('nested.test') instanceof mongoose.Schema.Types.String);
       });
+
+      it('nested array (gh-8627)', function() {
+        const schema = new Schema({
+          l1: {
+            type: {
+              l2: {
+                type: {
+                  test: String
+                }
+              }
+            }
+          }
+        }, { typePojoToMixed: false });
+
+        assert.ok(schema.path('l1').instance !== 'Mixed');
+        assert.ok(schema.path('l1.l2').instance !== 'Mixed');
+      });
     });
   });
   describe('with a parent with a POJO field with a field "type" with a type set to "String"', function() {

From 1271ff4c1c90a5771665826d043cdae0f550c12e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Mar 2020 07:51:14 -0700
Subject: [PATCH 0559/2348] test: repro #8645

---
 test/model.test.js | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 6b772613881..5f8401434c3 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5874,7 +5874,6 @@ describe('Model', function() {
         let M = db.model('Test', new Schema({
           name: { type: String, index: true }
         }, { autoIndex: false }), coll);
-
         let dropped = yield M.syncIndexes();
         assert.deepEqual(dropped, []);
 
@@ -5979,6 +5978,23 @@ describe('Model', function() {
       });
     });
 
+    it('syncIndexes() allows overwriting `background` option (gh-8645)', function() {
+      return co(function*() {
+        yield db.dropDatabase();
+
+        const opts = { autoIndex: false };
+        let schema = new Schema({ name: String }, opts);
+        schema.index({ name: 1 }, { background: true });
+
+        const M = db.model('Test', schema);
+        yield M.syncIndexes({ background: false });
+
+        const indexes = yield M.listIndexes();
+        assert.deepEqual(indexes[1].key, { name: 1 });
+        assert.strictEqual(indexes[1].background, false);
+      });
+    });
+
     it('using `new db.model()()` (gh-6698)', function(done) {
       db.model('Test', new Schema({
         name: String

From 7178eba7e88b6e0e54819f5d49d4ccb48a53966b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Mar 2020 07:51:39 -0700
Subject: [PATCH 0560/2348] fix(model): support passing `background` option to
 `syncIndexes()`

Fix #8645
---
 lib/model.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index cc09aa4b7ec..830d5a09ef2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1333,6 +1333,7 @@ Model.createCollection = function createCollection(options, callback) {
  *     await Customer.syncIndexes();
  *
  * @param {Object} [options] options to pass to `ensureIndexes()`
+ * @param {Boolean} [options.background=null] if specified, overrides each index's `background` property
  * @param {Function} [callback] optional callback
  * @return {Promise|undefined} Returns `undefined` if callback is specified, returns a promise if no callback.
  * @api public
@@ -1663,6 +1664,9 @@ function _ensureIndexes(model, options, callback) {
     if ('createIndex' in options) {
       useCreateIndex = !!options.createIndex;
     }
+    if ('background' in options) {
+      indexOptions.background = options.background;
+    }
 
     const methodName = useCreateIndex ? 'createIndex' : 'ensureIndex';
     model.collection[methodName](indexFields, indexOptions, utils.tick(function(err, name) {

From b5396f67bccd0f491a2e80661b1dfc6ce326a2e3 Mon Sep 17 00:00:00 2001
From: Dmitry Erastov <derastov@gmail.com>
Date: Sat, 7 Mar 2020 13:40:26 -0500
Subject: [PATCH 0561/2348] Correctly set message for ValidationError

Need to set the `_message` property before we pass it to the base constructor.

Discussed in d9163f561311642e36c79be4d40d396efe3f40af.
---
 lib/error/validation.js        |  2 +-
 test/errors.validation.test.js | 18 +++++++++++++-----
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/lib/error/validation.js b/lib/error/validation.js
index 950513575ed..6959ed5dc65 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -19,12 +19,12 @@ function ValidationError(instance) {
   this.errors = {};
   this._message = '';
 
-  MongooseError.call(this, this._message);
   if (instance && instance.constructor.name === 'model') {
     this._message = instance.constructor.modelName + ' validation failed';
   } else {
     this._message = 'Validation failed';
   }
+  MongooseError.call(this, this._message);
   this.name = 'ValidationError';
 
   if (Error.captureStackTrace) {
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 554847152e6..8be896f0468 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -59,6 +59,7 @@ describe('ValidationError', function() {
       // should fail validation
       model.validate(function(err) {
         assert.notEqual(err, null, 'min Date validation failed.');
+        assert.ok(err.message.startsWith('MinSchema validation failed'));
         model.appointmentDate = new Date(Date.now().valueOf() + 10000);
 
         // should pass validation
@@ -85,6 +86,7 @@ describe('ValidationError', function() {
       // should fail validation
       model.validate(function(err) {
         assert.notEqual(err, null, 'max Date validation failed');
+        assert.ok(err.message.startsWith('MaxSchema validation failed'));
         model.birthdate = Date.now();
 
         // should pass validation
@@ -111,6 +113,7 @@ describe('ValidationError', function() {
       // should fail validation
       model.validate(function(err) {
         assert.notEqual(err, null, 'String minlegth validation failed.');
+        assert.ok(err.message.startsWith('MinLengthAddress validation failed'));
         model.postalCode = '95125';
 
         // should pass validation
@@ -142,6 +145,7 @@ describe('ValidationError', function() {
       // should fail validation
       model.validate(function(err) {
         assert.equal(err.errors['postalCode'].message, 'woops!');
+        assert.ok(err.message.startsWith('gh4207 validation failed'));
         mongoose.Error.messages = old;
         done();
       });
@@ -163,6 +167,7 @@ describe('ValidationError', function() {
       // should fail validation
       model.validate(function(err) {
         assert.notEqual(err, null, 'String maxlegth validation failed.');
+        assert.ok(err.message.startsWith('MaxLengthAddress validation failed'));
         model.postalCode = '95125';
 
         // should pass validation
@@ -198,17 +203,16 @@ describe('ValidationError', function() {
   });
 
   describe('formatMessage', function() {
-    it('replaces properties in a message', function(done) {
+    it('replaces properties in a message', function() {
       const props = {base: 'eggs', topping: 'bacon'};
       const message = 'I had {BASE} and {TOPPING} for breakfast';
 
       const result = ValidatorError.prototype.formatMessage(message, props);
       assert.equal(result, 'I had eggs and bacon for breakfast');
-      done();
     });
   });
 
-  it('JSON.stringify() with message (gh-5309)', function(done) {
+  it('JSON.stringify() with message (gh-5309)', function() {
     model.modelName = 'TestClass';
     const err = new ValidationError(new model());
 
@@ -220,8 +224,12 @@ describe('ValidationError', function() {
     assert.ok(obj.message.indexOf('test: Fail') !== -1,
       obj.message);
 
-    done();
-
     function model() {}
   });
+
+  it('default error message', function() {
+    const err = new ValidationError();
+
+    assert.equal(err.message, 'Validation failed');
+  });
 });

From e746c39fa8d92aad4c48bcd16ee78ab6a6330069 Mon Sep 17 00:00:00 2001
From: Dmitry Erastov <derastov@gmail.com>
Date: Sat, 7 Mar 2020 13:51:14 -0500
Subject: [PATCH 0562/2348] Minor JSDoc wording fix for Document

---
 lib/document.js    | 7 ++-----
 test/model.test.js | 2 +-
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 3965d1cc8ad..ae368a616c3 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -55,7 +55,7 @@ const specialProperties = utils.specialProperties;
  * @param {Object} [fields] optional object containing the fields which were selected in the query returning this document and any populated paths data
  * @param {Boolean} [skipId] bool, should we auto create an ObjectId _id
  * @inherits NodeJS EventEmitter http://nodejs.org/api/events.html#events_class_events_eventemitter
- * @event `init`: Emitted on a document after it has was retreived from the db and fully hydrated by Mongoose.
+ * @event `init`: Emitted on a document after it has been retrieved from the db and fully hydrated by Mongoose.
  * @event `save`: Emitted when the document is successfully saved
  * @api private
  */
@@ -1162,10 +1162,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
         return false;
       }
       const modelName = val.get(refPath);
-      if (modelName === model.modelName || modelName === model.baseModelName) {
-        return true;
-      }
-      return false;
+      return modelName === model.modelName || modelName === model.baseModelName;
     })();
 
     let didPopulate = false;
diff --git a/test/model.test.js b/test/model.test.js
index 5f8401434c3..3e601fc8dcf 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5983,7 +5983,7 @@ describe('Model', function() {
         yield db.dropDatabase();
 
         const opts = { autoIndex: false };
-        let schema = new Schema({ name: String }, opts);
+        const schema = new Schema({ name: String }, opts);
         schema.index({ name: 1 }, { background: true });
 
         const M = db.model('Test', schema);

From 76de1125400d1f5f5c66d42f1c8e86cfd3a9abd1 Mon Sep 17 00:00:00 2001
From: Dmitry Erastov <derastov@gmail.com>
Date: Sat, 7 Mar 2020 14:17:37 -0500
Subject: [PATCH 0563/2348] Update some vulnerable dev dependencies

`eslint` has a new default error-level rule,
 `no-prototype-builtins`, so I set it to `warn` for now.
---
 package.json | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/package.json b/package.json
index 2fbb4ccef80..3fef78a4951 100644
--- a/package.json
+++ b/package.json
@@ -32,7 +32,7 @@
     "sift": "7.0.1"
   },
   "devDependencies": {
-    "acorn": "5.7.3",
+    "acorn": "7.1.1",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
@@ -45,12 +45,12 @@
     "cheerio": "1.0.0-rc.2",
     "co": "4.6.0",
     "dox": "0.3.1",
-    "eslint": "5.16.0",
+    "eslint": "6.8.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.1.0",
     "lodash.isequal": "4.5.0",
     "lodash.isequalwith": "4.4.0",
-    "marked": "0.6.2",
+    "marked": "0.8.0",
     "mocha": "5.x",
     "moment": "2.x",
     "mongodb-topology-manager": "1.0.11",
@@ -127,6 +127,7 @@
       "no-buffer-constructor": "warn",
       "no-console": "off",
       "no-multi-spaces": "error",
+      "no-prototype-builtins": "warn",
       "no-constant-condition": "off",
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",

From f00ae516c58e81d10ab89cd07087a90c4acad576 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Mar 2020 15:59:44 -0700
Subject: [PATCH 0564/2348] fix(array): make sure you can call `unshift()`
 after `slice()`

Fix #8482
---
 lib/types/core_array.js  | 11 +++++++++++
 test/model.test.js       |  2 +-
 test/types.array.test.js | 12 ++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 80b2026a227..d09bd8c715e 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -827,6 +827,17 @@ class CoreMongooseArray extends Array {
     return ret;
   }
 
+  /*!
+   * ignore
+   */
+
+  slice() {
+    const ret = super.slice.apply(this, arguments);
+    ret[arrayParentSymbol] = this[arrayParentSymbol];
+    ret[arraySchemaSymbol] = this[arraySchemaSymbol];
+    return ret;
+  }
+
   /*!
    * ignore
    */
diff --git a/test/model.test.js b/test/model.test.js
index 5f8401434c3..3e601fc8dcf 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5983,7 +5983,7 @@ describe('Model', function() {
         yield db.dropDatabase();
 
         const opts = { autoIndex: false };
-        let schema = new Schema({ name: String }, opts);
+        const schema = new Schema({ name: String }, opts);
         schema.index({ name: 1 }, { background: true });
 
         const M = db.model('Test', schema);
diff --git a/test/types.array.test.js b/test/types.array.test.js
index ea77f3ddd20..46dae50a947 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1658,6 +1658,18 @@ describe('types array', function() {
 
       assert.deepEqual(arr, [3, 5, 7, 11]);
     });
+
+    it('with unshift (gh-8482)', function() {
+      const M = db.model('Test', Schema({ arr: [Number] }));
+
+      const doc = new M({ arr: [1, 2, 3] });
+
+      const arr = doc.arr.slice(2);
+
+      arr.unshift(10);
+
+      assert.deepEqual(arr, [10, 3]);
+    });
   });
 
   describe('setting a doc array', function() {

From 7b0bd36225aa1e73200b64837989834ddde91a7f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Mar 2020 16:23:34 -0700
Subject: [PATCH 0565/2348] docs(schema): add a section about the `_id` path in
 schemas

Fix #8625
---
 docs/guide.pug | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/docs/guide.pug b/docs/guide.pug
index 1c13f251e8c..935e0cfc14e 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -26,6 +26,7 @@ block content
     <ul class="toc">
       <li><a href="#definition">Defining your schema</a></li>
       <li><a href="#models">Creating a model</a></li>
+      <li><a href="#_id">Ids</a></li>
       <li><a href="#methods">Instance methods</a></li>
       <li><a href="#statics">Statics</a></li>
       <li><a href="#query-helpers">Query Helpers</a></li>
@@ -114,6 +115,43 @@ block content
       // ready to go!
     ```
 
+    <h3 id="_id"><a href="#_id">Ids</a></h3>
+
+    By default, Mongoose adds an `_id` property to your schemas.
+
+    ```javascript
+    const schema = new Schema();
+
+    schema.path('_id'); // ObjectId { ... }
+    ```
+
+    When you create a new document with the automatically added
+    `_id` property, Mongoose createsa a new [`_id` of type ObjectId](https://masteringjs.io/tutorials/mongoose/objectid)
+    to your document.
+
+    ```javascript
+    const Model = mongoose.model('Test', schema);
+
+    const doc = new Model();
+    doc._id instanceof mongoose.Types.ObjectId; // true
+    ```
+
+    You can also overwrite Mongoose's default `_id` with your
+    own `_id`. Just be careful: Mongoose will refuse to save a
+    document that doesn't have an `_id`, so you're responsible
+    for setting `_id` if you define your own `_id` path.
+
+    ```javascript
+    const schema = new Schema({ _id: Number });
+    const Model = mongoose.model('Test', schema);
+
+    const doc = new Model();
+    await doc.save(); // Throws "document must have an _id before saving"
+    
+    doc._id = 1;
+    await doc.save(); // works
+    ```
+
     <h3 id="methods"><a href="#methods">Instance methods</a></h3>
 
     Instances of `Models` are [documents](./documents.html). Documents have

From c213424469800f25791868b2742542eff411912f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Mar 2020 16:32:34 -0700
Subject: [PATCH 0566/2348] chore: undo unnecessary changes

---
 package.json | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/package.json b/package.json
index 3fef78a4951..2fbb4ccef80 100644
--- a/package.json
+++ b/package.json
@@ -32,7 +32,7 @@
     "sift": "7.0.1"
   },
   "devDependencies": {
-    "acorn": "7.1.1",
+    "acorn": "5.7.3",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
@@ -45,12 +45,12 @@
     "cheerio": "1.0.0-rc.2",
     "co": "4.6.0",
     "dox": "0.3.1",
-    "eslint": "6.8.0",
+    "eslint": "5.16.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.1.0",
     "lodash.isequal": "4.5.0",
     "lodash.isequalwith": "4.4.0",
-    "marked": "0.8.0",
+    "marked": "0.6.2",
     "mocha": "5.x",
     "moment": "2.x",
     "mongodb-topology-manager": "1.0.11",
@@ -127,7 +127,6 @@
       "no-buffer-constructor": "warn",
       "no-console": "off",
       "no-multi-spaces": "error",
-      "no-prototype-builtins": "warn",
       "no-constant-condition": "off",
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",

From dfe41e29f00ab2e9e75106fbc08a3cf11a52b3e5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Mar 2020 17:17:52 -0600
Subject: [PATCH 0567/2348] fix(document): allow `new Model(doc)` to set
 immutable properties when doc is a mongoose document

Fix #8642
---
 lib/document.js       |  7 ++++---
 test/document.test.js | 11 +++++++++++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 3965d1cc8ad..09c5a89d740 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -128,15 +128,16 @@ function Document(obj, fields, skipId, options) {
   }
 
   if (obj) {
-    if (obj instanceof Document) {
-      this.isNew = obj.isNew;
-    }
     // Skip set hooks
     if (this.$__original_set) {
       this.$__original_set(obj, undefined, true);
     } else {
       this.$set(obj, undefined, true);
     }
+
+    if (obj instanceof Document) {
+      this.isNew = obj.isNew;
+    }
   }
 
   // Function defaults get applied **after** setting initial values so they
diff --git a/test/document.test.js b/test/document.test.js
index 22a38dff31a..f339777c7a2 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8829,4 +8829,15 @@ describe('document', function() {
       assert.ok(!err.errors['nested.age']);
     });
   });
+
+  it('copies immutable fields when constructing new doc from old doc (gh-8642)', function() {
+    const schema = Schema({ name: { type: String, immutable: true } });
+    const Model = db.model('Test', schema);
+
+    const doc = new Model({ name: 'test' });
+    doc.isNew = false;
+
+    const newDoc = new Model(doc);
+    assert.equal(newDoc.name, 'test');
+  });
 });

From 5c40f22b1036ef7003ec3ea118eeae4394c4eaba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Mar 2020 17:48:25 -0600
Subject: [PATCH 0568/2348] test(discriminator): clean up unnecessary
 collections in model.discriminator.test.js re: #8481

---
 test/model.discriminator.test.js | 185 +++++++++++++++----------------
 1 file changed, 90 insertions(+), 95 deletions(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 4bb6f86dc9b..0dbbf7a9152 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -74,23 +74,26 @@ describe('model', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   describe('discriminator()', function() {
     var Person, Employee;
 
     before(function() {
       db = start();
-      Person = db.model('model-discriminator-person', PersonSchema);
-      Employee = Person.discriminator('model-discriminator-employee', EmployeeSchema);
+      Person = db.model('Test', PersonSchema);
+      Employee = Person.discriminator('Employee', EmployeeSchema);
     });
 
     it('model defaults without discriminator', function(done) {
-      var Model = db.model('model-discriminator-defaults', new Schema(), 'model-discriminator-' + random());
+      var Model = db.model('Test1', new Schema());
       assert.equal(Model.discriminators, undefined);
       done();
     });
 
     it('is instance of root', function(done) {
-      assert.equal(Employee.baseModelName, 'model-discriminator-person');
+      assert.equal(Employee.baseModelName, 'Test');
       var employee = new Employee();
       assert.ok(employee instanceof Person);
       assert.ok(employee instanceof Employee);
@@ -136,20 +139,20 @@ describe('model', function() {
     });
 
     it('sets schema discriminator type mapping', function(done) {
-      assert.deepEqual(Employee.schema.discriminatorMapping, {key: '__t', value: 'model-discriminator-employee', isRoot: false});
+      assert.deepEqual(Employee.schema.discriminatorMapping, {key: '__t', value: 'Employee', isRoot: false});
       done();
     });
 
     it('adds discriminatorKey to schema with default as name', function(done) {
       var type = Employee.schema.paths.__t;
       assert.equal(type.options.type, String);
-      assert.equal(type.options.default, 'model-discriminator-employee');
+      assert.equal(type.options.default, 'Employee');
       done();
     });
 
     it('adds discriminator to Model.discriminators object', function(done) {
       assert.equal(Object.keys(Person.discriminators).length, 1);
-      assert.equal(Person.discriminators['model-discriminator-employee'], Employee);
+      assert.equal(Person.discriminators['Employee'], Employee);
       var newName = 'model-discriminator-' + random();
       var NewDiscriminatorType = Person.discriminator(newName, new Schema());
       assert.equal(Object.keys(Person.discriminators).length, 2);
@@ -190,34 +193,34 @@ describe('model', function() {
     it('throws error when discriminator has mapped discriminator key in schema with discriminatorKey option set', function(done) {
       assert.throws(
           function() {
-            var Foo = db.model('model-discriminator-foo', new Schema({}, {discriminatorKey: '_type'}), 'model-discriminator-' + random());
-            Foo.discriminator('model-discriminator-bar', new Schema({_type: String}));
+            var Foo = db.model('Test1', new Schema({}, {discriminatorKey: '_type'}), 'model-discriminator-' + random());
+            Foo.discriminator('Bar', new Schema({_type: String}));
           },
-          /Discriminator "model-discriminator-bar" cannot have field with name "_type"/
+          /Discriminator "Bar" cannot have field with name "_type"/
       );
       done();
     });
 
     it('throws error when discriminator with taken name is added', function(done) {
-      var Foo = db.model('model-discriminator-foo', new Schema({}), 'model-discriminator-' + random());
-      Foo.discriminator('model-discriminator-taken', new Schema());
+      var Foo = db.model('Test1', new Schema({}), 'model-discriminator-' + random());
+      Foo.discriminator('Token', new Schema());
       assert.throws(
           function() {
-            Foo.discriminator('model-discriminator-taken', new Schema());
+            Foo.discriminator('Token', new Schema());
           },
-          /Discriminator with name "model-discriminator-taken" already exists/
+          /Discriminator with name "Token" already exists/
       );
       done();
     });
 
     it('throws error if model name is taken (gh-4148)', function(done) {
-      var Foo = db.model('model-discriminator-4148', new Schema({}));
-      db.model('model-discriminator-4148-bar', new Schema({}));
+      var Foo = db.model('Test1', new Schema({}));
+      db.model('Bar', new Schema({}));
       assert.throws(
         function() {
-          Foo.discriminator('model-discriminator-4148-bar', new Schema());
+          Foo.discriminator('Bar', new Schema());
         },
-        /Cannot overwrite `model-discriminator-4148-bar`/);
+        /Cannot overwrite `Bar`/);
       done();
     });
 
@@ -248,8 +251,8 @@ describe('model', function() {
       }, { id: false });
 
       // Should not throw
-      var Person = db.model('gh2821', PersonSchema);
-      Person.discriminator('gh2821-Boss', BossSchema);
+      var Person = db.model('Test1', PersonSchema);
+      Person.discriminator('Boss', BossSchema);
       done();
     });
 
@@ -346,7 +349,7 @@ describe('model', function() {
 
       it('does not allow setting discriminator key (gh-2041)', function(done) {
         var doc = new Employee({ __t: 'fake' });
-        assert.equal(doc.__t, 'model-discriminator-employee');
+        assert.equal(doc.__t, 'Employee');
         doc.save(function(error) {
           assert.ok(error);
           assert.equal(error.errors['__t'].reason.message,
@@ -372,13 +375,13 @@ describe('model', function() {
 
         const parentSchema = new ActivityBaseSchema();
 
-        const model = db.model('gh2945', parentSchema);
+        const model = db.model('Test1', parentSchema);
 
         const commentSchema = new ActivityBaseSchema({
           text: { type: String, required: true }
         });
 
-        const D = model.discriminator('gh2945_0', commentSchema);
+        const D = model.discriminator('D', commentSchema);
 
         return new D({ text: 'test' }).validate().
           then(() => {
@@ -389,8 +392,8 @@ describe('model', function() {
       it('with typeKey (gh-4339)', function(done) {
         var options = { typeKey: '$type', discriminatorKey: '_t' };
         var schema = new Schema({ test: { $type: String } }, options);
-        var Model = mongoose.model('gh4339', schema);
-        Model.discriminator('gh4339_0', new Schema({
+        var Model = mongoose.model('Test', schema);
+        Model.discriminator('D', new Schema({
           test2: String
         }, { typeKey: '$type' }));
         done();
@@ -410,11 +413,11 @@ describe('model', function() {
           m.plugin(function() {
             ++called;
           });
-          var Model = m.model('gh4965', schema);
+          var Model = m.model('Test', schema);
           var childSchema = new m.Schema({
             test2: String
           });
-          Model.discriminator('gh4965_0', childSchema);
+          Model.discriminator('D', childSchema);
           assert.equal(called, 2);
   
           done();
@@ -445,17 +448,6 @@ describe('model', function() {
         });
       });
 
-      it('cloning with discriminator key (gh-4387)', function(done) {
-        var employee = new Employee({ name: { first: 'Val', last: 'Karpov' } });
-        var clone = new employee.constructor(employee);
-
-        // Should not error because we have the same discriminator key
-        clone.save(function(error) {
-          assert.ifError(error);
-          done();
-        });
-      });
-
       it('embedded discriminators with array defaults (gh-7687)', function() {
         const abstractSchema = new Schema({}, {
           discriminatorKey: 'kind',
@@ -502,7 +494,7 @@ describe('model', function() {
           }
         }, { _id: false }));
 
-        const Batch = db.model('EventBatch', batchSchema);
+        const Batch = db.model('Test', batchSchema);
 
         const batch = {
           events: [
@@ -544,7 +536,7 @@ describe('model', function() {
         mainSchema.path('types').discriminator(2,
           Schema({ hello: { type: String, default: 'world' } }));
 
-        const Model = db.model('gh7808', mainSchema);
+        const Model = db.model('Test1', mainSchema);
 
         return co(function*() {
           yield Model.create({
@@ -587,8 +579,8 @@ describe('model', function() {
           next();
         });
 
-        var Person = db.model('gh4983', personSchema);
-        var Parent = Person.discriminator('gh4983_0', parentSchema.clone());
+        var Person = db.model('Person', personSchema);
+        var Parent = Person.discriminator('Parent', parentSchema.clone());
 
         var obj = {
           name: 'Ned Stark',
@@ -619,10 +611,10 @@ describe('model', function() {
           child: String
         });
 
-        var Person = db.model('gh5098', personSchema);
-        var Parent = Person.discriminator('gh5098_0', parentSchema.clone());
+        var Person = db.model('Person', personSchema);
+        var Parent = Person.discriminator('Parent', parentSchema.clone());
         // Should not throw
-        var Parent2 = Person.discriminator('gh5098_1', parentSchema.clone());
+        var Parent2 = Person.discriminator('Parent2', parentSchema.clone());
         done();
       });
 
@@ -635,14 +627,14 @@ describe('model', function() {
           nameExt: String
         });
 
-        var ModelA = db.model('gh5721_a0', schema);
-        ModelA.discriminator('gh5721_a1', schemaExt);
+        var ModelA = db.model('Test1', schema);
+        ModelA.discriminator('D1', schemaExt);
 
         ModelA.findOneAndUpdate({}, { $set: { name: 'test' } }, function(error) {
           assert.ifError(error);
 
-          var ModelB = db.model('gh5721_b0', schema.clone());
-          ModelB.discriminator('gh5721_b1', schemaExt.clone());
+          var ModelB = db.model('Test2', schema.clone());
+          ModelB.discriminator('D2', schemaExt.clone());
 
           done();
         });
@@ -658,8 +650,8 @@ describe('model', function() {
             _advisor: String
           });
 
-          const Setting = db.model('gh6434_Setting', settingSchema);
-          const DefaultAdvisor = Setting.discriminator('gh6434_DefaultAdvisor',
+          const Setting = db.model('Test', settingSchema);
+          const DefaultAdvisor = Setting.discriminator('DefaultAdvisor',
             defaultAdvisorSchema);
 
           let threw = false;
@@ -672,7 +664,7 @@ describe('model', function() {
             threw = true;
             assert.equal(error.name, 'MongooseError');
             assert.equal(error.message, 'Discriminator "defaultAdvisor" not ' +
-              'found for model "gh6434_Setting"');
+              'found for model "Test"');
           }
           assert.ok(threw);
         });
@@ -687,14 +679,14 @@ describe('model', function() {
           ++eventSchemaCalls;
         });
 
-        var Event = db.model('gh5147', eventSchema);
+        var Event = db.model('Test', eventSchema);
 
         var clickedEventSchema = new mongoose.Schema({ url: String }, options);
         var clickedEventSchemaCalls = 0;
         clickedEventSchema.pre('findOneAndUpdate', function() {
           ++clickedEventSchemaCalls;
         });
-        var ClickedLinkEvent = Event.discriminator('gh5147_0', clickedEventSchema);
+        var ClickedLinkEvent = Event.discriminator('ClickedLink', clickedEventSchema);
 
         ClickedLinkEvent.findOneAndUpdate({}, { time: new Date() }, {}).
           exec(function(error) {
@@ -721,8 +713,8 @@ describe('model', function() {
 
         SecondContainerSchema.path('things').discriminator('Child', ChildSchema);
 
-        var M1 = db.model('gh5684_0', FirstContainerSchema);
-        var M2 = db.model('gh5684_1', SecondContainerSchema);
+        var M1 = db.model('Test1', FirstContainerSchema);
+        var M2 = db.model('Test2', SecondContainerSchema);
 
         var doc1 = new M1({ stuff: [{ __t: 'Child', name: 'test' }] });
         var doc2 = new M2({ things: [{ __t: 'Child', name: 'test' }] });
@@ -742,7 +734,7 @@ describe('model', function() {
           }
         });
 
-        const Model = db.model('gh6076', schema);
+        const Model = db.model('Test1', schema);
 
         const discSchema = mongoose.Schema({
           account: {
@@ -754,7 +746,7 @@ describe('model', function() {
           }
         });
 
-        const Disc = Model.discriminator('gh6076_0', discSchema);
+        const Disc = Model.discriminator('D', discSchema);
 
         const d1 = new Disc({
           account: {
@@ -782,7 +774,7 @@ describe('model', function() {
         var s = new Schema({ count: Number });
         collectionSchema.path('items').discriminator('type1', s);
 
-        var MyModel = db.model('Collection', collectionSchema);
+        var MyModel = db.model('Test', collectionSchema);
         var doc = {
           items: [{ type: 'type1', active: false, count: 3 }]
         };
@@ -801,10 +793,10 @@ describe('model', function() {
 
       it('with $meta projection (gh-5859)', function() {
         var eventSchema = new Schema({ eventField: String }, { id: false });
-        var Event = db.model('gh5859', eventSchema);
+        var Event = db.model('Test', eventSchema);
 
         var trackSchema = new Schema({ trackField: String });
-        var Track = Event.discriminator('gh5859_0', trackSchema);
+        var Track = Event.discriminator('Track', trackSchema);
 
         var trackedItem = new Track({
           trackField: 'trackField',
@@ -849,7 +841,7 @@ describe('model', function() {
           }
         }, { _id: false }));
 
-        var Batch = db.model('gh5009', batchSchema);
+        var Batch = db.model('Test', batchSchema);
 
         var batch = {
           events: [
@@ -900,7 +892,7 @@ describe('model', function() {
           }
         }, { _id: false }));
 
-        var Batch = db.model('gh5070', batchSchema);
+        var Batch = db.model('Test1', batchSchema);
 
         var batch = {
           events: [
@@ -951,7 +943,7 @@ describe('model', function() {
           }
         }));
 
-        var Batch = db.model('gh5130', batchSchema);
+        var Batch = db.model('Test1', batchSchema);
 
         var batch = {
           events: [
@@ -997,7 +989,7 @@ describe('model', function() {
           product: String
         }, { _id: false }));
 
-        var MyModel = db.model('gh2723', batchSchema);
+        var MyModel = db.model('Test1', batchSchema);
         var doc = {
           events: [
             { kind: 'Clicked', element: 'Test' },
@@ -1051,7 +1043,7 @@ describe('model', function() {
         product: String
       }, { _id: false }));
 
-      var MyModel = db.model('gh5244', trackSchema);
+      var MyModel = db.model('Test1', trackSchema);
       var doc1 = {
         event: {
           kind: 'Clicked',
@@ -1093,7 +1085,7 @@ describe('model', function() {
         product: String
       }, { _id: false }), 'purchase');
 
-      const MyModel = db.model('gh8164', trackSchema);
+      const MyModel = db.model('Test1', trackSchema);
       const doc1 = {
         event: {
           kind: 'click',
@@ -1135,7 +1127,7 @@ describe('model', function() {
       }, { _id: false });
       const Clicked = docArray.discriminator('Clicked', clickedSchema);
 
-      const M = db.model('gh6202', batchSchema);
+      const M = db.model('Test1', batchSchema);
 
       return M.create({ events: [[{ kind: 'Clicked', element: 'foo' }]] }).
         then(() => M.findOne()).
@@ -1178,12 +1170,12 @@ describe('model', function() {
 
       const schemaExt = new Schema({ nameExt: String });
       
-      const modelA = conA.model('A', schema);
+      const modelA = conA.model('Test', schema);
       modelA.discriminator('AExt', schemaExt);
       
       const conB = mongoose.createConnection(start.uri);
       
-      const modelB = conB.model('A', schema);
+      const modelB = conB.model('Test1', schema);
       modelB.discriminator('AExt', schemaExt);
       
     });
@@ -1283,7 +1275,7 @@ describe('model', function() {
         var embeddedEventSchema = trackSchema.path('events');
         embeddedEventSchema.discriminator('Purchased', purchasedSchema.clone());
 
-        var TrackModel = db.model('Track2', trackSchema);
+        var TrackModel = db.model('Track', trackSchema);
         var doc = new TrackModel({
           events: [
             {
@@ -1313,7 +1305,10 @@ describe('model', function() {
     it('should copy plugins', function () {
       const plugin = (schema) => { };
 
-      const schema = new Schema({ value: String });
+      const schema = new Schema({ value: String }, {
+        autoIndex: false,
+        autoCreate: false
+      });
       schema.plugin(plugin);
       const model = mongoose.model('Model', schema);
 
@@ -1367,13 +1362,13 @@ describe('model', function() {
         }
       }
 
-      class GH5227 extends BaseModel {
+      class Test extends BaseModel {
         getString() {
           return 'child';
         }
       }
 
-      const UserModel = mongoose.model(GH5227, new mongoose.Schema({}));
+      const UserModel = mongoose.model(Test, new mongoose.Schema({}));
 
       const u = new UserModel({});
 
@@ -1406,29 +1401,29 @@ describe('model', function() {
 
       const eventSchema = new mongoose.Schema({ time: Date }, options);
       const eventModelUser1 =
-        mongoose.model('gh7547_Event', eventSchema, 'user1_events');
+        mongoose.model('Test', eventSchema);
       const eventModelUser2 =
-        mongoose.model('gh7547_Event', eventSchema, 'user2_events');
+        mongoose.model('Test1', eventSchema);
 
       const discSchema = new mongoose.Schema({ url: String }, options);
       const clickEventUser1 = eventModelUser1.
-        discriminator('gh7547_ClickedEvent', discSchema);
+        discriminator('ClickedEvent', discSchema);
       const clickEventUser2 =
-        eventModelUser2.discriminators['gh7547_ClickedEvent'];
+        eventModelUser2.discriminators['ClickedEvent'];
 
-      assert.equal(clickEventUser1.collection.name, 'user1_events');
-      assert.equal(clickEventUser2.collection.name, 'user2_events');
+      assert.equal(clickEventUser1.collection.name, 'tests');
+      assert.equal(clickEventUser2.collection.name, 'test1');
     });
 
     it('uses correct discriminator when using `new BaseModel` (gh-7586)', function() {
       const options = { discriminatorKey: 'kind' };
 
-      const BaseModel = mongoose.model('gh7586_Base',
+      const BaseModel = mongoose.model('Parent',
         Schema({ name: String }, options));
-      const ChildModel = BaseModel.discriminator('gh7586_Child',
+      const ChildModel = BaseModel.discriminator('Child',
         Schema({ test: String }, options));
 
-      const doc = new BaseModel({ kind: 'gh7586_Child', name: 'a', test: 'b' });
+      const doc = new BaseModel({ kind: 'Child', name: 'a', test: 'b' });
       assert.ok(doc instanceof ChildModel);
       assert.equal(doc.test, 'b');
     });
@@ -1436,9 +1431,9 @@ describe('model', function() {
     it('uses correct discriminator when using `new BaseModel` with value (gh-7851)', function() {
       const options = { discriminatorKey: 'kind' };
 
-      const BaseModel = mongoose.model('gh7851_Base',
+      const BaseModel = mongoose.model('Parent',
         Schema({ name: String }, options));
-      const ChildModel = BaseModel.discriminator('gh7851_Child',
+      const ChildModel = BaseModel.discriminator('Child',
         Schema({ test: String }, options), 'child');
 
       const doc = new BaseModel({ kind: 'child', name: 'a', test: 'b' });
@@ -1452,8 +1447,8 @@ describe('model', function() {
         kind: { type: String, required: true }
       }, { discriminatorKey: 'kind' });
       
-      const Event = db.model('gh7807', eventSchema);
-      const Clicked = Event.discriminator('gh7807_Clicked',
+      const Event = db.model('Test', eventSchema);
+      const Clicked = Event.discriminator('Clicked',
         Schema({ url: String }));
 
       const doc = new Event({ title: 'foo' });
@@ -1480,7 +1475,7 @@ describe('model', function() {
       sectionsType.discriminator('image', imageSectionSchema);
       sectionsType.discriminator('text', textSectionSchema);
 
-      const Model = db.model('gh7574', documentSchema);
+      const Model = db.model('Test', documentSchema);
 
       return co(function*() {
         yield Model.create({
@@ -1505,9 +1500,9 @@ describe('model', function() {
       const opts = { discriminatorKey: 'kind' };
 
       const eventSchema = Schema({ lookups: [{ name: String }] }, opts);
-      const Event = db.model('gh7884_event', eventSchema);
+      const Event = db.model('Test', eventSchema);
 
-      const ClickedLinkEvent = Event.discriminator('gh7844_clicked', Schema({
+      const ClickedLinkEvent = Event.discriminator('Clicked', Schema({
         lookups: [{ hi: String }],
         url: String
       }, opts));
@@ -1531,18 +1526,18 @@ describe('model', function() {
           type: [{ _id: Number, action: String }]
         }
       });
-      schema.path('operations').discriminator('gh8274_test', new Schema({
+      schema.path('operations').discriminator('Pitch', new Schema({
         pitchPath: Schema({
           _id: Number,
           path: [{ _id: false, x: Number, y: Number }]
         })
       }));
-      const Model = db.model('gh8274', schema);
+      const Model = db.model('Test', schema);
 
       const doc = new Model();
       doc.operations.push({
         _id: 42,
-        __t: 'gh8274_test',
+        __t: 'Pitch',
         pitchPath: { path: [{ x: 1, y: 2 }] }
       });
       assert.strictEqual(doc.operations[0].pitchPath.path[0]._id, void 0);
@@ -1552,9 +1547,9 @@ describe('model', function() {
       const ProductSchema = new Schema({
         title: String
       });
-      const Product = mongoose.model('gh8273_Product', ProductSchema);
+      const Product = mongoose.model('Product', ProductSchema);
       const ProductItemSchema = new Schema({
-        product: { type: Schema.Types.ObjectId, ref: 'gh8273_Product' }
+        product: { type: Schema.Types.ObjectId, ref: 'Product' }
       });
 
       const OrderItemSchema = new Schema({}, {discriminatorKey: '__t'});

From f197ac37486cc59a058d83822d65e80b1ccbdc0d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Mar 2020 13:32:42 -0600
Subject: [PATCH 0569/2348] test: fix tests

---
 test/model.discriminator.test.js | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 0dbbf7a9152..94592b76c7b 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -392,7 +392,7 @@ describe('model', function() {
       it('with typeKey (gh-4339)', function(done) {
         var options = { typeKey: '$type', discriminatorKey: '_t' };
         var schema = new Schema({ test: { $type: String } }, options);
-        var Model = mongoose.model('Test', schema);
+        var Model = db.model('Test', schema);
         Model.discriminator('D', new Schema({
           test2: String
         }, { typeKey: '$type' }));
@@ -465,7 +465,7 @@ describe('model', function() {
 
         schema.path('items').discriminator('concrete', concreteSchema);
 
-        const Thing = mongoose.model('Thing', schema);
+        const Thing = db.model('Test', schema);
         const doc = new Thing();
 
         assert.equal(doc.items[0].foo, 42);
@@ -1325,7 +1325,7 @@ describe('model', function() {
       afterEach(function() { mongoose.deleteModel(/.+/); });
 
       it('does not modify _id path of the passed in schema the _id is not auto generated (gh-8543)', function() {
-        const model = mongoose.model('Model', new mongoose.Schema({ _id: Number }));
+        const model = db.model('Model', new mongoose.Schema({ _id: Number }));
         const passedInSchema = new mongoose.Schema({});
         model.discriminator('Discrimintaor', passedInSchema);
         assert.equal(passedInSchema.path('_id').instance, 'Number');
@@ -1336,9 +1336,9 @@ describe('model', function() {
       it('when the base schema has an _id that is not auto generated (gh-8543) (gh-8546)', function() {
         const unrelatedSchema = new mongoose.Schema({});
         unrelatedSchema.clone = throwErrorOnClone;
-        mongoose.model('UnrelatedModel', unrelatedSchema);
+        db.model('UnrelatedModel', unrelatedSchema);
 
-        const model = mongoose.model('Model', new mongoose.Schema({ _id: mongoose.Types.ObjectId }, { _id: false }));
+        const model = db.model('Model', new mongoose.Schema({ _id: mongoose.Types.ObjectId }, { _id: false }));
         model.discriminator('Discrimintaor', new mongoose.Schema({}).clone());
       });
     });
@@ -1401,9 +1401,9 @@ describe('model', function() {
 
       const eventSchema = new mongoose.Schema({ time: Date }, options);
       const eventModelUser1 =
-        mongoose.model('Test', eventSchema);
+        db.model('Test', eventSchema);
       const eventModelUser2 =
-        mongoose.model('Test1', eventSchema);
+        db.model('Test1', eventSchema);
 
       const discSchema = new mongoose.Schema({ url: String }, options);
       const clickEventUser1 = eventModelUser1.
@@ -1431,7 +1431,7 @@ describe('model', function() {
     it('uses correct discriminator when using `new BaseModel` with value (gh-7851)', function() {
       const options = { discriminatorKey: 'kind' };
 
-      const BaseModel = mongoose.model('Parent',
+      const BaseModel = db.model('Parent',
         Schema({ name: String }, options));
       const ChildModel = BaseModel.discriminator('Child',
         Schema({ test: String }, options), 'child');
@@ -1547,7 +1547,7 @@ describe('model', function() {
       const ProductSchema = new Schema({
         title: String
       });
-      const Product = mongoose.model('Product', ProductSchema);
+      const Product = db.model('Product', ProductSchema);
       const ProductItemSchema = new Schema({
         product: { type: Schema.Types.ObjectId, ref: 'Product' }
       });
@@ -1559,7 +1559,7 @@ describe('model', function() {
       });
 
       OrderSchema.path('items').discriminator('ProductItem', ProductItemSchema);
-      const Order = mongoose.model('Order', OrderSchema);
+      const Order = db.model('Order', OrderSchema);
 
       const product = new Product({title: 'Product title'});
 

From 122985dea6b6552c446f0ea76fa2a80f7e1cc81e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Mar 2020 13:42:58 -0600
Subject: [PATCH 0570/2348] test: fix tests

---
 test/model.discriminator.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 94592b76c7b..c51315aca43 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1397,13 +1397,13 @@ describe('model', function() {
     });
 
     it('with subclassing (gh-7547)', function() {
-      const options = { discriminatorKey: "kind" };
+      const options = { discriminatorKey: 'kind' };
 
       const eventSchema = new mongoose.Schema({ time: Date }, options);
       const eventModelUser1 =
-        db.model('Test', eventSchema);
+        mongoose.model('Test', eventSchema, 'tests');
       const eventModelUser2 =
-        db.model('Test1', eventSchema);
+        mongoose.model('Test', eventSchema, 'test1');
 
       const discSchema = new mongoose.Schema({ url: String }, options);
       const clickEventUser1 = eventModelUser1.

From c9f0ec920c38b87fa2102822da9abd61995ea68e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Mar 2020 13:52:00 -0600
Subject: [PATCH 0571/2348] test: fix tests

---
 test/model.discriminator.test.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index c51315aca43..d292e06edf7 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1400,6 +1400,7 @@ describe('model', function() {
       const options = { discriminatorKey: 'kind' };
 
       const eventSchema = new mongoose.Schema({ time: Date }, options);
+      mongoose.deleteModel(/Test/);
       const eventModelUser1 =
         mongoose.model('Test', eventSchema, 'tests');
       const eventModelUser2 =

From 321995d769ff085aa0a4553b2befb012eb2c11c8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Mar 2020 13:55:12 -0600
Subject: [PATCH 0572/2348] chore: release 5.9.4

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 4ac2051b24c..3953fe8a6a3 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.9.4 / 2020-03-09
+==================
+ * fix(document): allow `new Model(doc)` to set immutable properties when doc is a mongoose document #8642
+ * fix(array): make sure you can call `unshift()` after `slice()` #8482
+ * fix(schema): propagate `typePojoToMixed` to implicitly created arrays #8627
+ * fix(schema): also propagate `typePojoToMixed` option to schemas implicitly created because of `typePojoToMixed` #8627
+ * fix(model): support passing `background` option to `syncIndexes()` #8645
+ * docs(schema): add a section about the `_id` path in schemas #8625
+ * docs(virtualtype+populate): document using `match` with virtual populate #8616
+ * docs(guide): fix typo #8648 [sauzy34](https://github.com/sauzy34)
+
 5.9.3 / 2020-03-02
 ==================
  * fix: upgrade mongodb driver -> 3.5.4 #8620
diff --git a/package.json b/package.json
index 2fbb4ccef80..8ee4a3d4d19 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.3",
+  "version": "5.9.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 35cd71b971fce6d6b0f60c3320339d5be65cb0a8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Mar 2020 20:00:51 -0600
Subject: [PATCH 0573/2348] docs(guide): add section about `loadClass()`

Fix #8623
---
 docs/guide.pug | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/docs/guide.pug b/docs/guide.pug
index 935e0cfc14e..7531b4e0e04 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -34,6 +34,7 @@ block content
       <li><a href="#virtuals">Virtuals</a></li>
       <li><a href="#aliases">Aliases</a></li>
       <li><a href="#options">Options</a></li>
+      <li><a href="#es6-classes">With ES6 Classes</a></li>
       <li><a href="#plugins">Pluggable</a></li>
       <li><a href="#further-reading">Further Reading</a></li>
     </ul>
@@ -1142,6 +1143,32 @@ block content
     new Parent({ child: {} }).validateSync().errors;
     ```
 
+    <h3 id="es6-classes"><a href="#es6-classes">With ES6 Classes</a></h3>
+
+    Schemas have a [`loadClass()` method](/docs/api/schema.html#schema_Schema-loadClass)
+    that you can use to create a Mongoose schema from an [ES6 class](https://thecodebarbarian.com/an-overview-of-es6-classes):
+
+    * [ES6 class methods](https://masteringjs.io/tutorials/fundamentals/class#methods) become [Mongoose methods](/docs/guide.html#methods)
+    * [ES6 class statics](https://masteringjs.io/tutorials/fundamentals/class#statics) become [Mongoose statics](/docs/guide.html#statics)
+    * [ES6 getters and setters](https://masteringjs.io/tutorials/fundamentals/class#getterssetters) become [Mongoose virtuals](/docs/tutorials/virtuals.html)
+
+    Here's an example of using `loadClass()` to create a schema from an ES6 class:
+
+    ```javascript
+    class MyClass {
+      myMethod() { return 42; }
+      static myStatic() { return 42; }
+      get myVirtual() { return 42; }
+    }
+
+    const schema = new mongoose.Schema();
+    schema.loadClass(MyClass);
+
+    console.log(schema.methods); // { myMethod: [Function: myMethod] }
+    console.log(schema.statics); // { myStatic: [Function: myStatic] }
+    console.log(schema.virtuals); // { myVirtual: VirtualType { ... } }
+    ```
+
     <h3 id="plugins"><a href="#plugins">Pluggable</a></h3>
 
     Schemas are also [pluggable](./plugins.html) which allows us to package up reusable features into

From 3b4767db473f6fcc14b149ea4309be2d9bb877e5 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 11 Mar 2020 06:06:46 +0200
Subject: [PATCH 0574/2348] [WIP] Fixes #8658

---
 lib/model.js                |  6 +++++-
 test/model.populate.test.js | 24 +++++++++++++++++++++++-
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 830d5a09ef2..114af44d2c3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4424,11 +4424,15 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
     limit: mod.options.limit,
     perDocumentLimit: mod.options.perDocumentLimit
   }, mod.options.options);
+
   if (mod.count) {
     delete queryOptions.skip;
   }
 
-  if (queryOptions.perDocumentLimit != null) {
+  if (queryOptions.perDocumentLimit != null && queryOptions.limit != null) {
+    throw new Error('Can not use `limit` and `perDocumentLimit` at the same time. Model `' + mod.model.modelName + '`.' );
+  }
+  else if (queryOptions.perDocumentLimit != null) {
     queryOptions.limit = queryOptions.perDocumentLimit;
     delete queryOptions.perDocumentLimit;
   } else if (queryOptions.limit != null) {
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6425391fa6f..41452b0da8f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9200,4 +9200,26 @@ describe('model: populate:', function() {
       assert.deepEqual(res[0].toObject().list[0].data, { sourceId: 123 });
     });
   });
-});
+
+  it.only('throws an error when using limit with perDocumentLimit', function() {
+    return co(function *() {
+
+      const User = db.model('User',userSchema);
+      const BlogPost = db.model('BlogPost',blogPostSchema);
+
+      const blogPosts = yield BlogPost.create([{title:'JS 101'},{title:'Mocha 101'}]);
+      const user = yield User.create({blogposts: blogPosts});
+
+
+      let err;
+      try {
+        yield User.find({_id:user._id}).populate({ path: 'blogposts', perDocumentLimit: 2,limit:1 });
+      } catch (error) {
+        err = error;
+      }
+
+      assert(err);
+      assert.equal(err.message,'Can not use `limit` and `perDocumentLimit` at the same time. Model `BlogPost`.');
+    });
+  });
+});
\ No newline at end of file

From 1dc9b1ad8414c305103a1a35cefc734f8ac0841a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 11 Mar 2020 06:11:27 +0200
Subject: [PATCH 0575/2348] Remove .only

---
 test/model.populate.test.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 41452b0da8f..704c1cbf492 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9201,9 +9201,8 @@ describe('model: populate:', function() {
     });
   });
 
-  it.only('throws an error when using limit with perDocumentLimit', function() {
+  it('throws an error when using limit with perDocumentLimit', function() {
     return co(function *() {
-
       const User = db.model('User',userSchema);
       const BlogPost = db.model('BlogPost',blogPostSchema);
 

From 1d81906e9387ef09eaa13612b4ca4be86a61832c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:01:03 +0200
Subject: [PATCH 0576/2348] Throw error when using both limit and
 perDocumentLimit

---
 lib/model.js                   | 5 +----
 lib/options/PopulateOptions.js | 5 +++++
 test/model.populate.test.js    | 2 +-
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 114af44d2c3..8f6089e4f87 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4429,10 +4429,7 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
     delete queryOptions.skip;
   }
 
-  if (queryOptions.perDocumentLimit != null && queryOptions.limit != null) {
-    throw new Error('Can not use `limit` and `perDocumentLimit` at the same time. Model `' + mod.model.modelName + '`.' );
-  }
-  else if (queryOptions.perDocumentLimit != null) {
+  if (queryOptions.perDocumentLimit != null) {
     queryOptions.limit = queryOptions.perDocumentLimit;
     delete queryOptions.perDocumentLimit;
   } else if (queryOptions.limit != null) {
diff --git a/lib/options/PopulateOptions.js b/lib/options/PopulateOptions.js
index 4a188bd5171..a438dd1538f 100644
--- a/lib/options/PopulateOptions.js
+++ b/lib/options/PopulateOptions.js
@@ -14,6 +14,11 @@ class PopulateOptions {
     if (typeof obj.subPopulate === 'object') {
       this.populate = obj.subPopulate;
     }
+
+
+    if (obj.perDocumentLimit != null && obj.limit != null) {
+      throw new Error('Can not use `limit` and `perDocumentLimit` at the same time. Path: `' + obj.path + '`.' );
+    }
   }
 }
 
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 704c1cbf492..5b3f39b814f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9218,7 +9218,7 @@ describe('model: populate:', function() {
       }
 
       assert(err);
-      assert.equal(err.message,'Can not use `limit` and `perDocumentLimit` at the same time. Model `BlogPost`.');
+      assert.equal(err.message,'Can not use `limit` and `perDocumentLimit` at the same time. Path: `blogposts`.');
     });
   });
 });
\ No newline at end of file

From ed8a402352269d47285cbfb082f0af48fca810a6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:30:16 +0200
Subject: [PATCH 0577/2348] Add key-spacing eslint rule

---
 lib/helpers/populate/getVirtual.js  |  2 +-
 package.json                        |  6 ++++-
 test/collection.test.js             |  4 +--
 test/connection.test.js             |  4 +--
 test/document.test.js               | 30 +++++++++++------------
 test/model.findOneAndUpdate.test.js |  6 ++---
 test/model.populate.test.js         | 38 ++++++++++++++---------------
 test/model.query.casting.test.js    |  2 +-
 test/model.test.js                  |  4 +--
 test/model.update.test.js           |  6 ++---
 test/query.cursor.test.js           |  4 +--
 test/query.test.js                  | 18 +++++++-------
 test/schema.alias.test.js           | 28 ++++++++++-----------
 13 files changed, 78 insertions(+), 74 deletions(-)

diff --git a/lib/helpers/populate/getVirtual.js b/lib/helpers/populate/getVirtual.js
index 056828b85ec..3f4a129c91e 100644
--- a/lib/helpers/populate/getVirtual.js
+++ b/lib/helpers/populate/getVirtual.js
@@ -34,7 +34,7 @@ function getVirtual(schema, name) {
         if (i === parts.length - 2) {
           return {
             virtual: schema.virtuals[rest],
-            nestedSchemaPath:[nestedSchemaPath, cur].filter(v => !!v).join('.')
+            nestedSchemaPath: [nestedSchemaPath, cur].filter(v => !!v).join('.')
           };
         }
         continue;
diff --git a/package.json b/package.json
index 8ee4a3d4d19..b855ae5657a 100644
--- a/package.json
+++ b/package.json
@@ -130,6 +130,10 @@
       "no-constant-condition": "off",
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",
+      "key-spacing": [2, {
+        "beforeColon": false,
+        "afterColon": true
+      }],
       "quotes": [
         "error",
         "single"
@@ -164,4 +168,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
+}
\ No newline at end of file
diff --git a/test/collection.test.js b/test/collection.test.js
index a7d7ec2c27a..47587200c7c 100644
--- a/test/collection.test.js
+++ b/test/collection.test.js
@@ -28,7 +28,7 @@ describe('collections:', function() {
       });
     }
 
-    collection.insertOne({foo:'bar'}, {}, function(err, result) {
+    collection.insertOne({foo: 'bar'}, {}, function(err, result) {
       assert.ok(connected);
       insertedId = result.insertedId;
       finish();
@@ -45,7 +45,7 @@ describe('collections:', function() {
     const db = mongoose.createConnection();
     const collection = db.collection('gh7676');
 
-    const promise = collection.insertOne({foo:'bar'}, {})
+    const promise = collection.insertOne({foo: 'bar'}, {})
       .then(result =>
         collection.findOne({_id: result.insertedId})
       ).then(doc => {
diff --git a/test/connection.test.js b/test/connection.test.js
index ca2f212b645..10dd4975629 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -677,7 +677,7 @@ describe('connections:', function() {
     const coll = db.collection('Test');
     db.then(function() {
       setTimeout(function() {
-        coll.insertOne({x:1}, function(error) {
+        coll.insertOne({x: 1}, function(error) {
           assert.ok(error);
           done();
         });
@@ -703,7 +703,7 @@ describe('connections:', function() {
 
         let threw = false;
         try {
-          db.collection('Test').insertOne({x:1});
+          db.collection('Test').insertOne({x: 1});
         } catch (error) {
           threw = true;
           assert.ok(error);
diff --git a/test/document.test.js b/test/document.test.js
index f339777c7a2..783a326ba0e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2000,14 +2000,14 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const createdPerson = yield Person.create({name:'Hafez'});
-        const removedPerson = yield Person.findOneAndRemove({_id:createdPerson._id});
+        const createdPerson = yield Person.create({name: 'Hafez'});
+        const removedPerson = yield Person.findOneAndRemove({_id: createdPerson._id});
 
         removedPerson.isNew = true;
 
         yield removedPerson.save();
 
-        const foundPerson = yield Person.findOne({_id:removedPerson._id});
+        const foundPerson = yield Person.findOne({_id: removedPerson._id});
         assert.ok(foundPerson);
       });
     });
@@ -2017,7 +2017,7 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const createdPerson = yield Person.create({name:'Hafez'});
+        const createdPerson = yield Person.create({name: 'Hafez'});
 
         createdPerson.isNew = true;
 
@@ -2039,9 +2039,9 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const person = yield Person.create({name:'Hafez'});
+        const person = yield Person.create({name: 'Hafez'});
 
-        yield Person.deleteOne({_id:person._id});
+        yield Person.deleteOne({_id: person._id});
 
         let threw = false;
         try {
@@ -2062,9 +2062,9 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const person = yield Person.create({name:'Hafez'});
+        const person = yield Person.create({name: 'Hafez'});
 
-        yield Person.deleteOne({_id:person._id});
+        yield Person.deleteOne({_id: person._id});
 
         person.name = 'Different Name';
 
@@ -2956,13 +2956,13 @@ describe('document', function() {
 
     it('populate with lean (gh-3873)', function(done) {
       const companySchema = new mongoose.Schema({
-        name:  String,
-        description:  String,
+        name: String,
+        description: String,
         userCnt: { type: Number, default: 0, select: false }
       });
 
       const userSchema = new mongoose.Schema({
-        name:  String,
+        name: String,
         company: { type: mongoose.Schema.Types.ObjectId, ref: 'Company' }
       });
 
@@ -3253,7 +3253,7 @@ describe('document', function() {
           assert.ok(doc);
           doc.items[0] = {
             month: 5,
-            date : new Date()
+            date: new Date()
           };
           doc.markModified('items');
           doc.save(function(error) {
@@ -4075,7 +4075,7 @@ describe('document', function() {
       });
 
       const userSchema = new mongoose.Schema({
-        name:  String,
+        name: String,
         company: companySchema
       });
 
@@ -4196,7 +4196,7 @@ describe('document', function() {
         createdAt: { type: Date, required: true }
       });
       const RootSchema = new mongoose.Schema({
-        rootName:  String,
+        rootName: String,
         nested: { type: [ NestedSchema ] }
       });
 
@@ -8045,7 +8045,7 @@ describe('document', function() {
           return 'getter value';
         }
       }
-    }, { toObject : { getters: true } });
+    }, { toObject: { getters: true } });
 
     const Model = db.model('Test', schema);
 
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 719c1b03306..b000d76799b 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -875,7 +875,7 @@ describe('model: findOneAndUpdate:', function() {
     const Thing = db.model('Test', thingSchema);
     const key = 'some-new-id';
 
-    Thing.findOneAndUpdate({_id: key}, {$set: {flag: false}}, {upsert: true, new: false, rawResult:true}).exec(function(err, rawResult) {
+    Thing.findOneAndUpdate({_id: key}, {$set: {flag: false}}, {upsert: true, new: false, rawResult: true}).exec(function(err, rawResult) {
       assert.ifError(err);
       assert.equal(rawResult.lastErrorObject.updatedExisting, false );
       Thing.findOneAndUpdate({_id: key}, {$set: {flag: true}}, {upsert: true, new: false, rawResult: true}).exec(function(err, rawResult2) {
@@ -1770,7 +1770,7 @@ describe('model: findOneAndUpdate:', function() {
 
       const CollectionSchema = new Schema({
         field1: { type: String },
-        field2 : {
+        field2: {
           arrayField: [SubdocSchema]
         }
       }, options);
@@ -2100,7 +2100,7 @@ describe('model: findOneAndUpdate:', function() {
           $pull: {
             highlights: {
               _id: {
-                $in:  ['1', '2', '3', '4']
+                $in: ['1', '2', '3', '4']
               }
             }
           }
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6425391fa6f..b54322fce43 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -209,12 +209,12 @@ describe('model: populate:', function() {
 
     it('multiple paths with same options (gh-3808)', function(done) {
       const companySchema = new Schema({
-        name:  String,
-        description:  String
+        name: String,
+        description: String
       });
 
       const userSchema = new Schema({
-        name:  String,
+        name: String,
         company: {
           type: mongoose.Schema.Types.ObjectId,
           ref: 'Company',
@@ -223,7 +223,7 @@ describe('model: populate:', function() {
       });
 
       const messageSchema = new Schema({
-        message:  String,
+        message: String,
         author: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
         target: { type: mongoose.Schema.Types.ObjectId, ref: 'User' }
       });
@@ -4688,7 +4688,7 @@ describe('model: populate:', function() {
           a_id: { type: ObjectId }
         }, {
           toObject: { virtuals: true },
-          toJSON:   { virtuals: true }
+          toJSON: { virtuals: true }
         });
 
         BSchema.virtual('a', {
@@ -4724,7 +4724,7 @@ describe('model: populate:', function() {
           secondId: ObjectId
         }, {
           toObject: { virtuals: true },
-          toJSON:   { virtuals: true }
+          toJSON: { virtuals: true }
         });
 
         BSchema.virtual('a', {
@@ -5151,9 +5151,9 @@ describe('model: populate:', function() {
         });
 
         const blogPostSchema = new mongoose.Schema({
-          name : String,
+          name: String,
           body: String,
-          tags : [String]
+          tags: [String]
         });
 
         blogPostSchema.virtual('tagsDocuments', {
@@ -5167,16 +5167,16 @@ describe('model: populate:', function() {
 
         const tags = [
           {
-            name : 'angular.js',
-            tagId : 'angular'
+            name: 'angular.js',
+            tagId: 'angular'
           },
           {
-            name : 'node.js',
-            tagId : 'node'
+            name: 'node.js',
+            tagId: 'node'
           },
           {
-            name : 'javascript',
-            tagId : 'javascript'
+            name: 'javascript',
+            tagId: 'javascript'
           }
         ];
 
@@ -5731,7 +5731,7 @@ describe('model: populate:', function() {
 
       it('handles circular virtual -> regular (gh-5128)', function(done) {
         const ASchema = new Schema({
-          title: { type: String, required: true, trim : true }
+          title: { type: String, required: true, trim: true }
         });
 
         ASchema.virtual('brefs', {
@@ -5982,7 +5982,7 @@ describe('model: populate:', function() {
         const myModelSchema = new Schema({
           virtualRefKey: {type: String, ref: 'gh5331'}
         });
-        myModelSchema.set('toJSON', {virtuals:true});
+        myModelSchema.set('toJSON', {virtuals: true});
         myModelSchema.virtual('populatedVirtualRef', {
           ref: 'gh5331',
           localField: 'virtualRefKey',
@@ -6434,7 +6434,7 @@ describe('model: populate:', function() {
                 path: 'activity',
                 populate: { path: 'postedBy' }
               }).
-              sort({ seq:-1 });
+              sort({ seq: -1 });
           }).
           then(function(results) {
             assert.equal(results.length, 2);
@@ -7522,7 +7522,7 @@ describe('model: populate:', function() {
 
   it('respects schema array even if underlying doc doesnt use array (gh-6908)', function() {
     const jobSchema = new Schema({
-      company : [{ type: Schema.Types.ObjectId, ref: 'gh6908_Company' }]
+      company: [{ type: Schema.Types.ObjectId, ref: 'gh6908_Company' }]
     });
     const Job = db.model('gh6908_Job', jobSchema);
 
@@ -8350,7 +8350,7 @@ describe('model: populate:', function() {
     const Parent = db.model('Parent', Schema({
       list: [{
         fill: {
-          child: { type:ObjectId, ref:'Child' }
+          child: { type: ObjectId, ref: 'Child' }
         }
       }]
     }));
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index 20b7a5b5a2c..2c4d5c1c4f1 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -214,7 +214,7 @@ describe('model query casting', function() {
   it('works with $type matching', function(done) {
     const B = db.model(modelName, collection);
 
-    B.find({title: {$type: {x:1}}}, function(err) {
+    B.find({title: {$type: {x: 1}}}, function(err) {
       assert.equal(err.message, '$type parameter must be number or string');
 
       B.find({title: {$type: 2}}, function(err, posts) {
diff --git a/test/model.test.js b/test/model.test.js
index 3e601fc8dcf..00968bd0b0b 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5580,11 +5580,11 @@ describe('Model', function() {
 
       function test() {
         const schema = new mongoose.Schema({
-          amount : mongoose.Schema.Types.Decimal
+          amount: mongoose.Schema.Types.Decimal
         });
         const Money = db.model('Test', schema);
 
-        Money.insertMany([{ amount : '123.45' }], function(error) {
+        Money.insertMany([{ amount: '123.45' }], function(error) {
           assert.ifError(error);
           done();
         });
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 59030017b99..ed41f6cce6e 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -2203,7 +2203,7 @@ describe('model: update:', function() {
     it('single nested schema with geo (gh-4465)', function(done) {
       const addressSchema = new Schema({
         geo: {type: [Number], index: '2dsphere'}
-      }, { _id : false });
+      }, { _id: false });
       const containerSchema = new Schema({ address: addressSchema });
       const Container = db.model('Test', containerSchema);
 
@@ -3039,8 +3039,8 @@ describe('model: update:', function() {
 
       const Group = db.model('Group', GroupSchema);
       const update = {
-        users:[{
-          permission:{}
+        users: [{
+          permission: {}
         }]
       };
       const opts = {
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 7d4da6b2bcd..012da70d173 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -417,7 +417,7 @@ describe('QueryCursor', function() {
 
   it('addCursorFlag (gh-4814)', function(done) {
     const userSchema = new mongoose.Schema({
-      name:  String
+      name: String
     });
 
     const User = db.model('gh4814', userSchema);
@@ -432,7 +432,7 @@ describe('QueryCursor', function() {
 
   it('data before close (gh-4998)', function(done) {
     const userSchema = new mongoose.Schema({
-      name:  String
+      name: String
     });
 
     const User = db.model('gh4998', userSchema);
diff --git a/test/query.test.js b/test/query.test.js
index 58cafdb0d51..1f1d1ecb9ae 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1861,10 +1861,10 @@ describe('Query', function() {
       const locationSchema = new Schema({
         type: { type: String },
         coordinates: []
-      }, { _id:false });
+      }, { _id: false });
 
       const schema = new Schema({
-        title : String,
+        title: String,
         location: { type: locationSchema, required: true }
       });
       schema.index({ location: '2dsphere' });
@@ -1872,9 +1872,9 @@ describe('Query', function() {
       const Model = db.model('Test', schema);
 
       const query = {
-        location:{
-          $geoWithin:{
-            $geometry:{
+        location: {
+          $geoWithin: {
+            $geometry: {
               type: 'Polygon',
               coordinates: [[[-1,0],[-1,3],[4,3],[4,0],[-1,0]]]
             }
@@ -2005,8 +2005,8 @@ describe('Query', function() {
 
       const M = db.model('Test', schema);
       const q = M.find({
-        createdAt:{
-          $not:{
+        createdAt: {
+          $not: {
             $gte: '2016/09/02 00:00:00',
             $lte: '2016/09/02 23:59:59'
           }
@@ -2587,13 +2587,13 @@ describe('Query', function() {
         yield Activity.insertMany([
           {
             owner: {
-              id  : '5a042f742a91c1db447534d5',
+              id: '5a042f742a91c1db447534d5',
               type: 'user'
             }
           },
           {
             owner: {
-              id  : 'asdf',
+              id: 'asdf',
               type: 'tag'
             }
           }
diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index 41b7e81d20e..2e4eefd68af 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -25,14 +25,14 @@ describe('schema alias option', function() {
 
   it('works with all basic schema types', function(done) {
     const schema = new Schema({
-      string:   { type: String, alias: 'StringAlias' },
-      number:   { type: Number, alias: 'NumberAlias' },
-      date:     { type: Date, alias: 'DateAlias' },
-      buffer:   { type: Buffer, alias: 'BufferAlias' },
-      boolean:  { type: Boolean, alias: 'BooleanAlias' },
-      mixed:    { type: Schema.Types.Mixed, alias: 'MixedAlias' },
+      string: { type: String, alias: 'StringAlias' },
+      number: { type: Number, alias: 'NumberAlias' },
+      date: { type: Date, alias: 'DateAlias' },
+      buffer: { type: Buffer, alias: 'BufferAlias' },
+      boolean: { type: Boolean, alias: 'BooleanAlias' },
+      mixed: { type: Schema.Types.Mixed, alias: 'MixedAlias' },
       objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias'},
-      array:    { type: [], alias: 'ArrayAlias' }
+      array: { type: [], alias: 'ArrayAlias' }
     });
 
     const S = db.model('AliasSchemaType', schema);
@@ -64,14 +64,14 @@ describe('schema alias option', function() {
   it('works with nested schema types', function(done) {
     const schema = new Schema({
       nested: {
-        string:   { type: String, alias: 'StringAlias' },
-        number:   { type: Number, alias: 'NumberAlias' },
-        date:     { type: Date, alias: 'DateAlias' },
-        buffer:   { type: Buffer, alias: 'BufferAlias' },
-        boolean:  { type: Boolean, alias: 'BooleanAlias' },
-        mixed:    { type: Schema.Types.Mixed, alias: 'MixedAlias' },
+        string: { type: String, alias: 'StringAlias' },
+        number: { type: Number, alias: 'NumberAlias' },
+        date: { type: Date, alias: 'DateAlias' },
+        buffer: { type: Buffer, alias: 'BufferAlias' },
+        boolean: { type: Boolean, alias: 'BooleanAlias' },
+        mixed: { type: Schema.Types.Mixed, alias: 'MixedAlias' },
         objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias'},
-        array:    { type: [], alias: 'ArrayAlias' }
+        array: { type: [], alias: 'ArrayAlias' }
       }
     });
 

From 6396d45ffad34ce705ad8aa773e46f29adcf3286 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:32:10 +0200
Subject: [PATCH 0578/2348] Add comma-spacing and no-unreachable eslint rules

---
 lib/model.js                        |  2 +-
 lib/schema/map.js                   |  4 ++--
 package.json                        |  5 +++++
 test/aggregate.test.js              |  4 ++--
 test/document.test.js               | 12 ++++++------
 test/model.findOneAndUpdate.test.js |  2 +-
 test/model.populate.test.js         |  6 +++---
 test/model.test.js                  |  8 ++++----
 test/query.test.js                  |  2 +-
 test/schema.documentarray.test.js   |  2 +-
 10 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 830d5a09ef2..0d62ee723a7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -316,7 +316,7 @@ Model.prototype.$__handleSave = function(options, callback) {
     } else {
       this.constructor.exists(this.$__where(), saveOptions)
         .then((documentExists)=>{
-          if (!documentExists) throw new DocumentNotFoundError(this.$__where(),this.constructor.modelName);
+          if (!documentExists) throw new DocumentNotFoundError(this.$__where(), this.constructor.modelName);
 
           this.$__reset();
           callback();
diff --git a/lib/schema/map.js b/lib/schema/map.js
index 2db6bfc10b9..468faea9c07 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -17,8 +17,8 @@ class Map extends SchemaType {
     this.$isSchemaMap = true;
   }
 
-  set(option,value) {
-    return SchemaType.set(option,value);
+  set(option, value) {
+    return SchemaType.set(option, value);
   }
 
   cast(val, doc, init) {
diff --git a/package.json b/package.json
index b855ae5657a..08f35ed67db 100644
--- a/package.json
+++ b/package.json
@@ -134,6 +134,11 @@
         "beforeColon": false,
         "afterColon": true
       }],
+      "comma-spacing": [2, {
+        "before": false,
+        "after": true
+      }],
+      "no-unreachable": 2,
       "quotes": [
         "error",
         "single"
diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index c12c9d6b44d..2eb0f301471 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -495,8 +495,8 @@ describe('aggregate: ', function() {
         assert.equal(aggregate.addFields({ a: 1, b: 1, c: 0 }), aggregate);
         assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }]);
 
-        aggregate.addFields({ d: {$add: ['$a','$b']} });
-        assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }, { $addFields: { d: {$add: ['$a','$b']} } }]);
+        aggregate.addFields({ d: {$add: ['$a', '$b']} });
+        assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }, { $addFields: { d: {$add: ['$a', '$b']} } }]);
         done();
       });
     });
diff --git a/test/document.test.js b/test/document.test.js
index 783a326ba0e..b25fb2b0916 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2030,7 +2030,7 @@ describe('document', function() {
           assert.equal(err.code, 11000);
         }
 
-        assert.equal(threw,true);
+        assert.equal(threw, true);
       });
     });
 
@@ -2049,11 +2049,11 @@ describe('document', function() {
         }
         catch (err) {
           assert.equal(err instanceof DocumentNotFoundError, true);
-          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "Person"`);
+          assert.equal(err.message, `No document found for query "{ _id: ${person._id} }" on model "Person"`);
           threw = true;
         }
 
-        assert.equal(threw,true);
+        assert.equal(threw, true);
       });
     });
 
@@ -2073,12 +2073,12 @@ describe('document', function() {
           yield person.save();
         }
         catch (err) {
-          assert.equal(err instanceof DocumentNotFoundError,true);
-          assert.equal(err.message,`No document found for query "{ _id: ${person._id} }" on model "Person"`);
+          assert.equal(err instanceof DocumentNotFoundError, true);
+          assert.equal(err.message, `No document found for query "{ _id: ${person._id} }" on model "Person"`);
           threw = true;
         }
 
-        assert.equal(threw,true);
+        assert.equal(threw, true);
       });
     });
   });
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index b000d76799b..951afe44b6e 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -2146,7 +2146,7 @@ describe('model: findOneAndUpdate:', function() {
       }, { collection: 'users' });
 
       UserSchema.pre('findOneAndUpdate', function() {
-        this.update({},{ $set: {lastUpdate: new Date()} });
+        this.update({}, { $set: {lastUpdate: new Date()} });
       });
 
       const User = db.model('User', UserSchema);
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index b54322fce43..d7a0fef7a59 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -6954,7 +6954,7 @@ describe('model: populate:', function() {
         const clickedSchema = new Schema({
           element: { type: String },
           users: [Number]
-        },{
+        }, {
           toJSON: { virtuals: true },
           toObject: { virtuals: true }
         });
@@ -7305,7 +7305,7 @@ describe('model: populate:', function() {
 
     const eventSchema = new Schema({
       message: String
-    },{ discriminatorKey: 'kind' });
+    }, { discriminatorKey: 'kind' });
 
     const batchSchema = new Schema({
       events: [eventSchema]
@@ -7608,7 +7608,7 @@ describe('model: populate:', function() {
       return new Author({ name: `author${n}`});
     });
 
-    const comments = 'abc'.split('').map((l,i) => {
+    const comments = 'abc'.split('').map((l, i) => {
       const id = authors[i]._id;
       return new Comment({ text: `comment_${l}`, author: id });
     });
diff --git a/test/model.test.js b/test/model.test.js
index 00968bd0b0b..cfad8b9a8c2 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -3589,12 +3589,12 @@ describe('Model', function() {
           b.save(function() {
             b.elements.push({el: 'd'});
             b.test = 'a';
-            b.save(function(error,res) {
+            b.save(function(error, res) {
               assert.ok(error);
-              assert.strictEqual(res,undefined);
-              b.save(function(error,res) {
+              assert.strictEqual(res, undefined);
+              b.save(function(error, res) {
                 assert.ok(error);
-                assert.strictEqual(res,undefined);
+                assert.strictEqual(res, undefined);
                 M.collection.drop(done);
               });
             });
diff --git a/test/query.test.js b/test/query.test.js
index 1f1d1ecb9ae..43420df052c 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1876,7 +1876,7 @@ describe('Query', function() {
           $geoWithin: {
             $geometry: {
               type: 'Polygon',
-              coordinates: [[[-1,0],[-1,3],[4,3],[4,0],[-1,0]]]
+              coordinates: [[[-1, 0], [-1, 3], [4, 3], [4, 0], [-1, 0]]]
             }
           }
         }
diff --git a/test/schema.documentarray.test.js b/test/schema.documentarray.test.js
index 208446dddeb..920705b1f58 100644
--- a/test/schema.documentarray.test.js
+++ b/test/schema.documentarray.test.js
@@ -94,7 +94,7 @@ describe('schema.documentarray', function() {
     assert.equal(doc.nested[0].length, 1);
     assert.equal(doc.nested[0][0].title, 'new');
 
-    doc.nested = [[{ title: 'first' }, { title: 'second' },{ title: 'third' }]];
+    doc.nested = [[{ title: 'first' }, { title: 'second' }, { title: 'third' }]];
     assert.equal(doc.nested[0].length, 3);
     assert.equal(doc.nested[0][1].title, 'second');
   });

From 439145a39ced1dd49ef49fe58f5f35191e97303d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:33:56 +0200
Subject: [PATCH 0579/2348] Add array-bracket-spacing

---
 lib/document.js                          | 4 ++--
 lib/plugins/validateBeforeSave.js        | 2 +-
 package.json                             | 1 +
 test/aggregate.test.js                   | 4 ++--
 test/document.test.js                    | 4 ++--
 test/helpers/populate.getVirtual.test.js | 4 ++--
 test/model.populate.test.js              | 6 +++---
 test/model.querying.test.js              | 2 +-
 test/model.test.js                       | 2 +-
 test/model.update.test.js                | 2 +-
 test/query.test.js                       | 4 ++--
 test/schema.documentarray.test.js        | 2 +-
 12 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index c87aba59e8f..f4e69050c07 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2305,7 +2305,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     return process.nextTick(function() {
       const error = _complete();
       if (error) {
-        return _this.schema.s.hooks.execPost('validate:error', _this, [ _this], { error: error }, function(error) {
+        return _this.schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
           callback(error);
         });
       }
@@ -2319,7 +2319,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   const complete = function() {
     const error = _complete();
     if (error) {
-      return _this.schema.s.hooks.execPost('validate:error', _this, [ _this], { error: error }, function(error) {
+      return _this.schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
         callback(error);
       });
     }
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index 6c57d006c4f..a486ca2c854 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -33,7 +33,7 @@ module.exports = function(schema) {
         {validateModifiedOnly: options.validateModifiedOnly} :
         null;
       this.validate(validateOptions, function(error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [ _this], { error: error }, function(error) {
+        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           _this.$op = 'save';
           next(error);
         });
diff --git a/package.json b/package.json
index 08f35ed67db..5cb06816ead 100644
--- a/package.json
+++ b/package.json
@@ -138,6 +138,7 @@
         "before": false,
         "after": true
       }],
+      "array-bracket-spacing": 1,
       "no-unreachable": 2,
       "quotes": [
         "error",
diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 2eb0f301471..dcd28155bb4 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -421,7 +421,7 @@ describe('aggregate: ', function() {
       const aggregate = new Aggregate();
       aggregate.redact({
         $cond: {
-          if: { $eq: [ '$level', 5 ] },
+          if: { $eq: ['$level', 5] },
           then: '$$PRUNE',
           else: '$$DESCEND'
         }
@@ -564,7 +564,7 @@ describe('aggregate: ', function() {
         aggregate.replaceRoot({ x: { $concat: ['$this', '$that'] } });
 
         assert.deepEqual(aggregate._pipeline,
-          [{ $replaceRoot: { newRoot: { x: { $concat: ['$this', '$that'] } } } } ]);
+          [{ $replaceRoot: { newRoot: { x: { $concat: ['$this', '$that'] } } } }]);
         done();
       });
     });
diff --git a/test/document.test.js b/test/document.test.js
index b25fb2b0916..7b0420d3814 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -4197,11 +4197,11 @@ describe('document', function() {
       });
       const RootSchema = new mongoose.Schema({
         rootName: String,
-        nested: { type: [ NestedSchema ] }
+        nested: { type: [NestedSchema] }
       });
 
       const Root = db.model('Test', RootSchema);
-      const root = new Root({ rootName: 'root', nested: [ { } ] });
+      const root = new Root({ rootName: 'root', nested: [{ }] });
       root.save(function(error) {
         assert.ok(error);
         assert.deepEqual(Object.keys(error.errors).sort(),
diff --git a/test/helpers/populate.getVirtual.test.js b/test/helpers/populate.getVirtual.test.js
index 6f6f2d75454..7e2c1457b60 100644
--- a/test/helpers/populate.getVirtual.test.js
+++ b/test/helpers/populate.getVirtual.test.js
@@ -23,7 +23,7 @@ describe('getVirtual', function() {
     // First embedded discriminator has a virtual
     const clickedSchema = new Schema({
       element: { type: String },
-      users: [ Number ]
+      users: [Number]
     });
 
     clickedSchema.virtual('users_$', {
@@ -55,7 +55,7 @@ describe('getVirtual', function() {
     const docArray = batchSchema.path('nested.events');
 
     // *** Adding Nested Layer and adding virtual to schema of nestedLayer
-    const nestedLayerSchema = new Schema({ users: [ Number ] }, {
+    const nestedLayerSchema = new Schema({ users: [Number] }, {
       toJSON: { virtuals: true},
       toObject: { virtuals: true }
     });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index d7a0fef7a59..bcab929e7c0 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -6581,7 +6581,7 @@ describe('model: populate:', function() {
         const clickedSchema = new Schema(
           {
             element: { type: String },
-            users: [ Number ]
+            users: [Number]
           },
           {
             toJSON: { virtuals: true},
@@ -7894,7 +7894,7 @@ describe('model: populate:', function() {
 
     const t = new Trick({ description: 'roll over'});
     const d = new Dog({ name: 'Fido', trick: t._id });
-    const o = new Owner({ name: 'Bill', age: 10, dogs: [ d._id ] });
+    const o = new Owner({ name: 'Bill', age: 10, dogs: [d._id] });
 
     return co(function*() {
       yield [t.save(), d.save(), o.save()];
@@ -8579,7 +8579,7 @@ describe('model: populate:', function() {
       const eventSchema = Schema({ message: String }, { discriminatorKey: 'kind' });
       const batchSchema = Schema({ nested: { events: [eventSchema] } });
 
-      const nestedLayerSchema = Schema({ users: [ Number ] });
+      const nestedLayerSchema = Schema({ users: [Number] });
       nestedLayerSchema.virtual('users_$', {
         ref: 'User',
         localField: 'users',
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 139a298c535..d53af3b2886 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -1853,7 +1853,7 @@ describe('model: querying:', function() {
     const docA = {name: 'A', block: new MongooseBuffer([195, 188, 98, 101, 114])}; // über
     const docB = {name: 'B', block: new MongooseBuffer('buffer shtuffs are neat')};
     const docC = {name: 'C', block: new MongooseBuffer('aGVsbG8gd29ybGQ=', 'base64')};
-    const docD = {name: 'D', block: new MongooseBuffer({ type: 'Buffer', data: [ 103, 104, 45, 54, 56, 54, 51 ] })};
+    const docD = {name: 'D', block: new MongooseBuffer({ type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] })};
 
     Test.create(docA, docB, docC, docD, function(err, a, b, c, d) {
       if (err) return done(err);
diff --git a/test/model.test.js b/test/model.test.js
index cfad8b9a8c2..e3a6ec5e720 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4872,7 +4872,7 @@ describe('Model', function() {
           ]);
 
           yield MyModel.updateMany({}, { $set: { 'grades.$[element]': 100 } }, {
-            arrayFilters: [ { element: { $gte: 100 } } ]
+            arrayFilters: [{ element: { $gte: 100 } }]
           });
 
           const docs = yield MyModel.find().sort({ _id: 1 });
diff --git a/test/model.update.test.js b/test/model.update.test.js
index ed41f6cce6e..1b719a52555 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -2303,7 +2303,7 @@ describe('model: update:', function() {
     it('findOneAndUpdate with nested arrays (gh-5032)', function(done) {
       const schema = Schema({
         name: String,
-        inputs: [ [ String ] ] // Array of Arrays of Strings
+        inputs: [[String]] // Array of Arrays of Strings
       });
 
       const Activity = db.model('Test', schema);
diff --git a/test/query.test.js b/test/query.test.js
index 43420df052c..f850b3cdd50 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -2033,13 +2033,13 @@ describe('Query', function() {
       const ls = {
         name: 'test',
         geo: {
-          coordinates: [ [14.59, 24.847], [28.477, 15.961] ]
+          coordinates: [[14.59, 24.847], [28.477, 15.961]]
         }
       };
       const ls2 = {
         name: 'test2',
         geo: {
-          coordinates: [ [27.528, 25.006], [14.063, 15.591] ]
+          coordinates: [[27.528, 25.006], [14.063, 15.591]]
         }
       };
       LineString.create(ls, ls2, function(error, ls1) {
diff --git a/test/schema.documentarray.test.js b/test/schema.documentarray.test.js
index 920705b1f58..e0cc59b8a87 100644
--- a/test/schema.documentarray.test.js
+++ b/test/schema.documentarray.test.js
@@ -81,7 +81,7 @@ describe('schema.documentarray', function() {
     });
 
     const nestedSchema = new Schema({
-      nested: [[ subSchema ]]
+      nested: [[subSchema]]
     });
 
     const Nested = mongoose.model('gh7799', nestedSchema);

From 8d0afae3acc28d16e4314bd5faecc00f08634903 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:35:13 +0200
Subject: [PATCH 0580/2348] Disallow comma dangle

---
 lib/drivers/node-mongodb-native/collection.js |  2 +-
 package.json                                  |  1 +
 test/document.populate.test.js                |  6 +--
 test/document.test.js                         | 40 +++++++++----------
 test/helpers/clone.test.js                    |  2 +-
 test/helpers/populate.getSchemaTypes.test.js  |  2 +-
 test/helpers/update.castArrayFilters.test.js  |  2 +-
 test/model.findOneAndUpdate.test.js           |  2 +-
 test/model.populate.test.js                   | 26 ++++++------
 test/model.test.js                            |  4 +-
 test/model.translateAliases.test.js           |  2 +-
 test/model.update.test.js                     |  2 +-
 test/query.test.js                            |  2 +-
 test/schema.singlenestedpath.test.js          | 24 +++++------
 test/schema.test.js                           |  4 +-
 test/timestamps.test.js                       |  6 +--
 .../types.embeddeddocumentdeclarative.test.js | 12 +++---
 test/webpack.test.js                          |  2 +-
 webpack.base.config.js                        |  6 +--
 webpack.config.js                             |  4 +-
 20 files changed, 76 insertions(+), 75 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 380e0f1c567..7351ebe0d64 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -257,7 +257,7 @@ NativeCollection.prototype.$format = function(arg, color) {
 
 function inspectable(representation) {
   const ret = {
-    inspect: function() { return representation; },
+    inspect: function() { return representation; }
   };
   if (util.inspect.custom) {
     ret[util.inspect.custom] = ret.inspect;
diff --git a/package.json b/package.json
index 5cb06816ead..6c5ddd47b16 100644
--- a/package.json
+++ b/package.json
@@ -139,6 +139,7 @@
         "after": true
       }],
       "array-bracket-spacing": 1,
+      "comma-dangle": [2, "never"],
       "no-unreachable": 2,
       "quotes": [
         "error",
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index 9ab17579bd5..0bbb2d2dd2a 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -774,7 +774,7 @@ describe('document.populate', function() {
         'gh_7740_2',
         new mongoose.Schema({
           name: String,
-          books: { type: [{ type: mongoose.Schema.Types.ObjectId, ref: 'gh_7740_1' }], default: [] },
+          books: { type: [{ type: mongoose.Schema.Types.ObjectId, ref: 'gh_7740_1' }], default: [] }
         })
       );
 
@@ -907,7 +907,7 @@ describe('document.populate', function() {
 
     before(function() {
       const playerSchema = mongoose.Schema({
-        _id: String,
+        _id: String
       });
 
       const teamSchema = mongoose.Schema({
@@ -934,7 +934,7 @@ describe('document.populate', function() {
               return v.split(' ')[0];
             }
           }
-        })],
+        })]
       });
 
       Player = db.model('gh7521_Player', playerSchema);
diff --git a/test/document.test.js b/test/document.test.js
index 7b0420d3814..06549371e51 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -563,14 +563,14 @@ describe('document', function() {
     const clipSchema = Schema({
       height: Number,
       rows: Number,
-      width: Number,
+      width: Number
     }, {_id: false, id: false});
     const questionSchema = Schema({
       type: String,
       age: Number,
       clip: {
-        type: clipSchema,
-      },
+        type: clipSchema
+      }
     }, {_id: false, id: false});
     const keySchema = Schema({ql: [questionSchema]}, {_id: false, id: false});
     const Model = db.model('gh8468-2', Schema({
@@ -584,9 +584,9 @@ describe('document', function() {
           { type: 'mc', clip: {width: 1} },
           { type: 'mc', clip: {height: 1, rows: 1} },
           { type: 'mc', clip: {height: 2, rows: 1} },
-          { type: 'mc', clip: {height: 3, rows: 1} },
-        ]},
-      ],
+          { type: 'mc', clip: {height: 3, rows: 1} }
+        ]}
+      ]
     });
     return doc.save().then(() => {
       // The following was failing before fixing gh-8531 because
@@ -3642,7 +3642,7 @@ describe('document', function() {
             }
           },
           members: [{
-            name: String,
+            name: String
           }]
         });
 
@@ -3673,16 +3673,16 @@ describe('document', function() {
         const testSchema = new Schema({
           name: {
             first: String,
-            last: String,
+            last: String
           },
           relatives: {
             aunt: {
-              name: String,
+              name: String
             },
             uncle: {
-              name: String,
-            },
-          },
+              name: String
+            }
+          }
         });
         const M = db.model('Test', testSchema);
 
@@ -6992,9 +6992,9 @@ describe('document', function() {
       roles: {
         type: [{
           otherProperties: {
-            example: Boolean,
+            example: Boolean
           },
-          name: String,
+          name: String
         }],
         default: function() {
           return [
@@ -7102,7 +7102,7 @@ describe('document', function() {
     const ActivityBareSchema = new Schema({
       _id: {
         type: Schema.Types.ObjectId,
-        ref: 'Activity',
+        ref: 'Activity'
       },
       name: String
     });
@@ -7117,7 +7117,7 @@ describe('document', function() {
       activity: {
         _id: '5bf606f6471b6056b3f2bfc9',
         name: 'Activity name'
-      },
+      }
     };
 
     const Event = db.model('Test', EventSchema);
@@ -7616,20 +7616,20 @@ describe('document', function() {
       minimize: false, // So empty objects are returned
       strict: true,
       typeKey: '$type', // So that we can use fields named `type`
-      discriminatorKey: 'type',
+      discriminatorKey: 'type'
     };
 
     const IssueSchema = new mongoose.Schema({
       _id: String,
       text: String,
-      type: String,
+      type: String
     }, opts);
 
     const IssueModel = db.model('Test', IssueSchema);
 
     const SubIssueSchema = new mongoose.Schema({
       checklist: [{
-        completed: {$type: Boolean, default: false},
+        completed: {$type: Boolean, default: false}
       }]
     }, opts);
     IssueModel.discriminator('gh7704_sub', SubIssueSchema);
@@ -8535,7 +8535,7 @@ describe('document', function() {
       startDate: {
         type: Date,
         required: true,
-        min: [new Date('2020-01-01'), () => 'test'],
+        min: [new Date('2020-01-01'), () => 'test']
       }
     });
 
diff --git a/test/helpers/clone.test.js b/test/helpers/clone.test.js
index 4e1590c5ba4..367682775bb 100644
--- a/test/helpers/clone.test.js
+++ b/test/helpers/clone.test.js
@@ -170,7 +170,7 @@ describe('clone', () => {
         [symbols.schemaTypeSymbol]: 'MyType',
         clone() {
           return {
-            myAttr: this.myAttr,
+            myAttr: this.myAttr
           };
         }
       };
diff --git a/test/helpers/populate.getSchemaTypes.test.js b/test/helpers/populate.getSchemaTypes.test.js
index e71da6583dd..01472c9c3c1 100644
--- a/test/helpers/populate.getSchemaTypes.test.js
+++ b/test/helpers/populate.getSchemaTypes.test.js
@@ -148,7 +148,7 @@ describe('getSchemaTypes', function() {
     });
 
     const ProducerSchema = new mongoose.Schema({
-      name: 'String',
+      name: 'String'
     });
 
     const Driver = mongoose.model('gh6798_Driver', DriverSchema);
diff --git a/test/helpers/update.castArrayFilters.test.js b/test/helpers/update.castArrayFilters.test.js
index b7d2afaabae..17e64de2991 100644
--- a/test/helpers/update.castArrayFilters.test.js
+++ b/test/helpers/update.castArrayFilters.test.js
@@ -69,7 +69,7 @@ describe('castArrayFilters', function() {
         allUsers: { all: Number },
         individual: [{
           userId: String,
-          all: Number,
+          all: Number
         }]
       }
     });
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 951afe44b6e..61da9a25602 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -1240,7 +1240,7 @@ describe('model: findOneAndUpdate:', function() {
         username: String,
         socialMediaHandles: {
           type: Map,
-          of: socialMediaHandleSchema,
+          of: socialMediaHandleSchema
         }
       });
 
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index bcab929e7c0..892b58e5500 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -3191,7 +3191,7 @@ describe('model: populate:', function() {
 
       const user = {
         _id: mongoose.Types.ObjectId(),
-        name: 'Arnold',
+        name: 'Arnold'
       };
 
       const post = {
@@ -6094,7 +6094,7 @@ describe('model: populate:', function() {
           let Company = db.model('gh6245', CompanySchema);
           const company = new Company({
             name: 'Uber',
-            departments: [{name: 'Security'}, {name: 'Engineering'}],
+            departments: [{name: 'Security'}, {name: 'Engineering'}]
           });
 
           yield company.save();
@@ -6838,7 +6838,7 @@ describe('model: populate:', function() {
             },
             populate: {
               path: 'user',
-              select: 'name -_id',
+              select: 'name -_id'
             }
           };
           return Post.find(cond, null, opts).populate(pop).exec();
@@ -6863,7 +6863,7 @@ describe('model: populate:', function() {
 
       it('honors top-level match with subPopulation (gh-6451)', function() {
         const anotherSchema = new Schema({
-          name: String,
+          name: String
         });
 
         const Another = db.model('Test2', anotherSchema);
@@ -6923,7 +6923,7 @@ describe('model: populate:', function() {
             match: { online: true },
             populate: {
               path: 'a',
-              select: '-_id name',
+              select: '-_id name'
             }
           };
           const doc = yield Test.findOne({ visible: true }).populate(popObj);
@@ -7074,7 +7074,7 @@ describe('model: populate:', function() {
         metadata: {
           type: Schema.Types.ObjectId,
           ref: 'Test'
-        },
+        }
       });
 
       const postSchema = new Schema({
@@ -7727,7 +7727,7 @@ describe('model: populate:', function() {
 
     const commentSchema = new Schema({
       postId: { type: Schema.Types.ObjectId },
-      text: String,
+      text: String
     });
 
     const Post = db.model('Post', postSchema);
@@ -8618,7 +8618,7 @@ describe('model: populate:', function() {
       name: String,
       children: [{
         barId: { type: Schema.Types.ObjectId, ref: 'Test' },
-        quantity: Number,
+        quantity: Number
       }]
     });
     FooSchema.virtual('children.bar', {
@@ -8757,7 +8757,7 @@ describe('model: populate:', function() {
       mainSchema.virtual('virtualField', {
         ref: 'Test1',
         localField: '_id',
-        foreignField: 'main',
+        foreignField: 'main'
       });
 
       const discriminatedSchema = new Schema({ description: String });
@@ -8918,11 +8918,11 @@ describe('model: populate:', function() {
         type: ObjectId,
         refPath: 'list.objectType'
       },
-      objectType: String,
+      objectType: String
     }, opts);
     const ItemSchemaB = Schema({
       data: { sourceId: Number },
-      objectType: String,
+      objectType: String
     }, opts);
 
     const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
@@ -9136,13 +9136,13 @@ describe('model: populate:', function() {
     const noId = { _id: false };
 
     const NestedDataSchema = Schema({
-      data: Schema({ title: String, description: String }, noId),
+      data: Schema({ title: String, description: String }, noId)
     }, noId);
 
     const InternalItemSchemaGen = () => Schema({
       data: {
         type: ObjectId,
-        refPath: 'list.objectType',
+        refPath: 'list.objectType'
       }
     }, noId);
 
diff --git a/test/model.test.js b/test/model.test.js
index e3a6ec5e720..cabd9d2fce0 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5447,7 +5447,7 @@ describe('Model', function() {
             {
               updateOne: {
                 filter: {},
-                update: { $set: { 'children.$[].name': 'bar' } },
+                update: { $set: { 'children.$[].name': 'bar' } }
               }
             }
           ]);
@@ -6274,7 +6274,7 @@ describe('Model', function() {
       yield SampleModel.bulkWrite([{
         insertOne: {
           doc: { name: 'Samwell Tarly' }
-        },
+        }
       }, {
         replaceOne: {
           filter: { name: 'bar' },
diff --git a/test/model.translateAliases.test.js b/test/model.translateAliases.test.js
index 944e4fb7bb9..1e390bc5b0c 100644
--- a/test/model.translateAliases.test.js
+++ b/test/model.translateAliases.test.js
@@ -56,7 +56,7 @@ describe('model translate aliases', function() {
         ['name', 'Stark'],
         ['_id', '1'],
         ['bio.age', 30],
-        ['d.s', 'DotSyntax'],
+        ['d.s', 'DotSyntax']
       ])
     );
   });
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 1b719a52555..d2031a3c81e 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -2501,7 +2501,7 @@ describe('model: update:', function() {
             [0, 1],
             [2, 3],
             [4, 5]
-          ],
+          ]
         }
       });
 
diff --git a/test/query.test.js b/test/query.test.js
index f850b3cdd50..e28cb656c8e 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -2618,7 +2618,7 @@ describe('Query', function() {
 
         const OrderSchema = new Schema({
           lines: [new Schema({
-            amount: Number,
+            amount: Number
           }, { discriminatorKey: 'kind' })]
         });
 
diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
index 83c21a11dd8..9a43be927b8 100644
--- a/test/schema.singlenestedpath.test.js
+++ b/test/schema.singlenestedpath.test.js
@@ -15,7 +15,7 @@ describe('SingleNestedPath', function() {
     describe('recursive nested discriminators', function() {
       it('allow multiple levels of data in the schema', function() {
         const singleEventSchema = new Schema({
-          message: String,
+          message: String
         }, { _id: false, discriminatorKey: 'kind' });
 
         const subEventSchema = new Schema({
@@ -35,7 +35,7 @@ describe('SingleNestedPath', function() {
 
       it('allow multiple levels of data in a document', function() {
         const singleEventSchema = new Schema({
-          message: String,
+          message: String
         }, { _id: false, discriminatorKey: 'kind' });
 
         const subEventSchema = new Schema({
@@ -61,10 +61,10 @@ describe('SingleNestedPath', function() {
                 sub_events: [{
                   kind: 'SubEvent',
                   message: 'level 5',
-                  sub_events: [],
-                }],
-              }],
-            }],
+                  sub_events: []
+                }]
+              }]
+            }]
           }]
         };
         const subEvent = SubEvent(multiLevel);
@@ -75,7 +75,7 @@ describe('SingleNestedPath', function() {
       it('allow multiple levels of data in the schema when the base schema has _id without auto', function() {
         const singleEventSchema = new Schema({
           _id: { type: Number, required: true },
-          message: String,
+          message: String
         }, { discriminatorKey: 'kind' });
 
         const subEventSchema = new Schema({
@@ -100,7 +100,7 @@ describe('SingleNestedPath', function() {
       it('allow multiple levels of data in a document when the base schema has _id without auto', function() {
         const singleEventSchema = new Schema({
           _id: { type: Number, required: true },
-          message: String,
+          message: String
         }, { discriminatorKey: 'kind' });
 
         const subEventSchema = new Schema({
@@ -131,10 +131,10 @@ describe('SingleNestedPath', function() {
                   _id: 1,
                   kind: 'SubEvent',
                   message: 'level 5',
-                  sub_events: [],
-                }],
-              }],
-            }],
+                  sub_events: []
+                }]
+              }]
+            }]
           }]
         };
         const subEvent = SubEvent(multiLevel);
diff --git a/test/schema.test.js b/test/schema.test.js
index d065f8ca282..963db49f2e7 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -888,7 +888,7 @@ describe('schema', function() {
         }, { discriminatorKey: 'kind', _id: false });
 
         const batchSchema = new Schema({
-          events: [eventSchema],
+          events: [eventSchema]
         });
 
         const docArray = batchSchema.path('events');
@@ -898,7 +898,7 @@ describe('schema', function() {
         }, { _id: false }));
 
         docArray.discriminator('gh6485_Purchased', Schema({
-          product: { type: String, index: true },
+          product: { type: String, index: true }
         }, { _id: false }));
 
         assert.deepEqual(batchSchema.indexes().map(v => v[0]), [
diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index 2c3ab4fddec..52b6f38f4fe 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -187,12 +187,12 @@ describe('timestamps', function() {
     const modelSchema = new Schema({
       createdAt: {
         type: Date,
-        get: (date) => date && date.valueOf() / 1000,
+        get: (date) => date && date.valueOf() / 1000
       },
       updatedAt: {
         type: Date,
-        get: (date) => date && date.valueOf() / 1000,
-      },
+        get: (date) => date && date.valueOf() / 1000
+      }
     }, { timestamps: true });
 
     const Model = db.model('gh7496', modelSchema);
diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
index 9f520208bba..6b6cfdea93a 100644
--- a/test/types.embeddeddocumentdeclarative.test.js
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -37,7 +37,7 @@ describe('types.embeddeddocumentdeclarative', function() {
           name: 'Swamp Guide',
           child: {
             name: 'Tingle',
-            mixedUp: 'very',
+            mixedUp: 'very'
           }
         });
         const tingle = swampGuide.toObject().child;
@@ -60,7 +60,7 @@ describe('types.embeddeddocumentdeclarative', function() {
           name: 'King Daphnes Nohansen Hyrule',
           child: {
             name: 'Princess Zelda',
-            mixedUp: 'not',
+            mixedUp: 'not'
           }
         });
         const princessZelda = kingDaphnes.child.toObject();
@@ -107,8 +107,8 @@ describe('types.embeddeddocumentdeclarative', function() {
       child: {
         name: String,
         type: {
-          type: String,
-        },
+          type: String
+        }
       }
     };
     const ParentSchemaNotMixed = new Schema(ParentSchemaDef);
@@ -132,7 +132,7 @@ describe('types.embeddeddocumentdeclarative', function() {
         child: {
           name: 'Rito Chieftan',
           type: 'Mother',
-          confidence: 10,
+          confidence: 10
         }
       });
       const ritoChieftan = new ParentModelNotSubdoc({
@@ -140,7 +140,7 @@ describe('types.embeddeddocumentdeclarative', function() {
         child: {
           name: 'Prince Komali',
           type: 'Medli',
-          confidence: 1,
+          confidence: 1
         }
       });
 
diff --git a/test/webpack.test.js b/test/webpack.test.js
index 0ff909433f0..831630cbb8b 100644
--- a/test/webpack.test.js
+++ b/test/webpack.test.js
@@ -40,7 +40,7 @@ describe('webpack', function() {
         // acquit:ignore:start
         output: {
           path: `${__dirname}/files`
-        },
+        }
         // acquit:ignore:end
       });
       // acquit:ignore:start
diff --git a/webpack.base.config.js b/webpack.base.config.js
index c7286bece6a..33327617e57 100644
--- a/webpack.base.config.js
+++ b/webpack.base.config.js
@@ -7,7 +7,7 @@ module.exports = {
         test: /\.js$/,
         include: [
           /\/mongoose\//i,
-          /\/kareem\//i,
+          /\/kareem\//i
         ],
         loader: 'babel-loader',
         options: {
@@ -24,10 +24,10 @@ module.exports = {
     fs: 'empty',
     module: 'empty',
     net: 'empty',
-    tls: 'empty',
+    tls: 'empty'
   },
   target: 'web',
-  mode: 'production',
+  mode: 'production'
 };
 
 
diff --git a/webpack.config.js b/webpack.config.js
index ce1faa8b343..b6c6cca53be 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -13,11 +13,11 @@ const webpackConfig = Object.assign({}, base, {
     libraryTarget: 'umd',
     // override default 'window' globalObject so browser build will work in SSR environments
     // may become unnecessary in webpack 5
-    globalObject: 'typeof self !== \'undefined\' ? self : this',
+    globalObject: 'typeof self !== \'undefined\' ? self : this'
   },
   externals: [
     /^node_modules\/.+$/
-  ],
+  ]
 });
 
 module.exports = webpackConfig;

From fd6c220833a002db51c49a24d2f285cd37f3fd49 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:37:16 +0200
Subject: [PATCH 0581/2348] Add quote props as needed

---
 package.json                        |  2 ++
 test/document.test.js               | 14 +++++++-------
 test/errors.validation.test.js      |  2 +-
 test/model.findOneAndUpdate.test.js |  4 ++--
 test/model.indexes.test.js          |  2 +-
 test/model.populate.test.js         | 10 +++++-----
 test/model.querying.test.js         | 24 ++++++++++++------------
 test/model.test.js                  |  2 +-
 test/model.translateAliases.test.js | 12 ++++++------
 test/model.update.test.js           | 14 +++++++-------
 test/types.map.test.js              |  4 ++--
 11 files changed, 46 insertions(+), 44 deletions(-)

diff --git a/package.json b/package.json
index 6c5ddd47b16..90c216f9fd2 100644
--- a/package.json
+++ b/package.json
@@ -124,6 +124,7 @@
         }
       ],
       "keyword-spacing": "error",
+      "no-whitespace-before-property": "error",
       "no-buffer-constructor": "warn",
       "no-console": "off",
       "no-multi-spaces": "error",
@@ -145,6 +146,7 @@
         "error",
         "single"
       ],
+      "quote-props": ["error", "as-needed"],
       "semi": "error",
       "space-before-blocks": "error",
       "space-before-function-paren": [
diff --git a/test/document.test.js b/test/document.test.js
index 06549371e51..57f953b95cc 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -3090,7 +3090,7 @@ describe('document', function() {
       const Model = db.model('Test1', ModelSchema);
 
       const nestedModel = new NestedModel({
-        'field': 'nestedModel'
+        field: 'nestedModel'
       });
 
       nestedModel.save(function(error, nestedModel) {
@@ -3301,14 +3301,14 @@ describe('document', function() {
       const ChildSchema = new Schema({
         name: {
           type: String,
-          'default': 'child'
+          default: 'child'
         }
       });
 
       const ParentSchema = new Schema({
         child: {
           type: ChildSchema,
-          'default': {}
+          default: {}
         }
       });
 
@@ -7737,11 +7737,11 @@ describe('document', function() {
   });
 
   it('does not crash with array property named "undefined" (gh-7756)', function() {
-    const schema = new Schema({ 'undefined': [String] });
+    const schema = new Schema({ undefined: [String] });
     const Model = db.model('Test', schema);
 
     return co(function*() {
-      const doc = yield Model.create({ 'undefined': ['foo'] });
+      const doc = yield Model.create({ undefined: ['foo'] });
 
       doc['undefined'].push('bar');
       yield doc.save();
@@ -8691,7 +8691,7 @@ describe('document', function() {
 
     const subdocumentSchema = Schema({
       placedItems: {
-        '1': placedItemSchema,
+        1: placedItemSchema,
         first: placedItemSchema
       }
     });
@@ -8699,7 +8699,7 @@ describe('document', function() {
 
     return co(function*() {
       const doc = yield Model.create({
-        placedItems: { '1': { image: 'original' }, first: { image: 'original' } }
+        placedItems: { 1: { image: 'original' }, first: { image: 'original' } }
       });
 
       doc.set({
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 8be896f0468..cfb566480cc 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -127,7 +127,7 @@ describe('ValidationError', function() {
     it('with correct error message (gh-4207)', function(done) {
       const old = mongoose.Error.messages;
       mongoose.Error.messages = {
-        'String': {
+        String: {
           minlength: 'woops!'
         }
       };
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 61da9a25602..9e040c8d0ae 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -1655,7 +1655,7 @@ describe('model: findOneAndUpdate:', function() {
         ]
       };
       const opts = {
-        'new': true,
+        new: true,
         upsert: false,
         passRawResult: false,
         overwrite: false,
@@ -2338,7 +2338,7 @@ describe('model: findOneAndUpdate:', function() {
     return co(function*() {
       let doc = yield Model.create({ name: 'test', __v: 10 });
       yield Model.findByIdAndUpdate(doc._id, {
-        '$unset': { name: '' },
+        $unset: { name: '' },
         __v: 0
       }, { upsert: true });
 
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index dfa45f582ef..3b4f390a9ec 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -250,7 +250,7 @@ describe('model', function() {
       assert.deepEqual(ContainerSchema.indexes().map(function(v) { return v[0]; }), [
         { 'sub.subSub.nested2': 1 },
         { 'sub.nested1': 1 },
-        { 'nested0': 1 }
+        { nested0: 1 }
       ]);
 
       done();
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 892b58e5500..87d85257413 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -642,7 +642,7 @@ describe('model: populate:', function() {
 
         BlogPost
           .findById(post._id)
-          .populate('_creator', {'name': 1})
+          .populate('_creator', {name: 1})
           .exec(function(err, post) {
             assert.ifError(err);
 
@@ -1339,7 +1339,7 @@ describe('model: populate:', function() {
 
           BlogPost
             .findById(post._id)
-            .populate('comments._creator', {'email': 1}, {name: /User/})
+            .populate('comments._creator', {email: 1}, {name: /User/})
             .exec(function(err, post) {
               assert.ifError(err);
 
@@ -1786,7 +1786,7 @@ describe('model: populate:', function() {
               assert.equal(post.fans[3].name, 'aaron');
 
               P.findById(post)
-                .populate('fans', 'name', null, {sort: {'name': -1}})
+                .populate('fans', 'name', null, {sort: {name: -1}})
                 .exec(function(err, post) {
                   assert.ifError(err);
 
@@ -1801,7 +1801,7 @@ describe('model: populate:', function() {
                   assert.strictEqual(undefined, post.fans[0].age);
 
                   P.findById(post)
-                    .populate('fans', 'age', {age: {$gt: 3}}, {sort: {'name': 'desc'}})
+                    .populate('fans', 'age', {age: {$gt: 3}}, {sort: {name: 'desc'}})
                     .exec(function(err, post) {
                       assert.ifError(err);
 
@@ -7012,7 +7012,7 @@ describe('model: populate:', function() {
         flexibleItemSchema.add({ outer: outerSchema });
         outerSchema.add({ inner: innerSchema });
         innerSchema.add({
-          flexible: [new Schema({ 'kind': String }, { discriminatorKey: 'kind' })]
+          flexible: [new Schema({ kind: String }, { discriminatorKey: 'kind' })]
         });
 
         const docArray = innerSchema.path('flexible');
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index d53af3b2886..dbc039d204d 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -564,7 +564,7 @@ describe('model: querying:', function() {
           assert.ifError(err);
           found.id;
           assert.equal(found._id.toString(), created._id);
-          const query = {sigs: {'$in': [Buffer.from([3, 3, 3]), Buffer.from([4, 5, 6])]}};
+          const query = {sigs: {$in: [Buffer.from([3, 3, 3]), Buffer.from([4, 5, 6])]}};
           BlogPostB.findOne(query, function(err) {
             assert.ifError(err);
             done();
@@ -611,7 +611,7 @@ describe('model: querying:', function() {
 
       BlogPostB.create({owners: [id1, id2]}, function(err, created) {
         assert.ifError(err);
-        BlogPostB.findOne({owners: {'$elemMatch': {$in: [id2.toString()]}}}, function(err, found) {
+        BlogPostB.findOne({owners: {$elemMatch: {$in: [id2.toString()]}}}, function(err, found) {
           assert.ifError(err);
           assert.ok(found);
           assert.equal(created.id, found.id);
@@ -866,7 +866,7 @@ describe('model: querying:', function() {
         NE.create({ids: [id2, id4], b: id3}, function(err) {
           assert.ifError(err);
 
-          const query = NE.find({'b': id3.toString(), 'ids': {$ne: id1}});
+          const query = NE.find({b: id3.toString(), ids: {$ne: id1}});
           query.exec(function(err, nes1) {
             assert.ifError(err);
             assert.equal(nes1.length, 1);
@@ -983,7 +983,7 @@ describe('model: querying:', function() {
 
       BlogPostB.create({owners: [id1, id2]}, function(err) {
         assert.ifError(err);
-        BlogPostB.find({owners: {'$elemMatch': {$in: [id2.toString()]}}}, function(err, found) {
+        BlogPostB.find({owners: {$elemMatch: {$in: [id2.toString()]}}}, function(err, found) {
           assert.ifError(err);
           assert.equal(found.length, 1);
           done();
@@ -1221,23 +1221,23 @@ describe('model: querying:', function() {
         BlogPostB.findById(post._id, function(err, post) {
           assert.ifError(err);
 
-          BlogPostB.find({title: {'$all': ['Aristocats']}}, function(err, docs) {
+          BlogPostB.find({title: {$all: ['Aristocats']}}, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
 
-            BlogPostB.find({title: {'$all': [/^Aristocats/]}}, function(err, docs) {
+            BlogPostB.find({title: {$all: [/^Aristocats/]}}, function(err, docs) {
               assert.ifError(err);
               assert.equal(docs.length, 1);
 
-              BlogPostB.find({tags: {'$all': ['onex', 'twox', 'threex']}}, function(err, docs) {
+              BlogPostB.find({tags: {$all: ['onex', 'twox', 'threex']}}, function(err, docs) {
                 assert.ifError(err);
                 assert.equal(docs.length, 1);
 
-                BlogPostB.find({tags: {'$all': [/^onex/i]}}, function(err, docs) {
+                BlogPostB.find({tags: {$all: [/^onex/i]}}, function(err, docs) {
                   assert.ifError(err);
                   assert.equal(docs.length, 1);
 
-                  BlogPostB.findOne({tags: {'$all': /^two/}}, function(err, doc) {
+                  BlogPostB.findOne({tags: {$all: /^two/}}, function(err, doc) {
                     assert.ifError(err);
                     assert.equal(post.id, doc.id);
                     done();
@@ -1373,7 +1373,7 @@ describe('model: querying:', function() {
 
         pending = 2;
 
-        D.find({'dt': {$gte: '2011-03-30', $lte: '2011-04-01'}}).sort('dt').exec(function(err, docs) {
+        D.find({dt: {$gte: '2011-03-30', $lte: '2011-04-01'}}).sort('dt').exec(function(err, docs) {
           if (!--pending) {
             done();
           }
@@ -1387,7 +1387,7 @@ describe('model: querying:', function() {
           }));
         });
 
-        D.find({'dt': {$gt: '2011-03-30', $lt: '2011-04-02'}}).sort('dt').exec(function(err, docs) {
+        D.find({dt: {$gt: '2011-03-30', $lt: '2011-04-02'}}).sort('dt').exec(function(err, docs) {
           if (!--pending) {
             done();
           }
@@ -2008,7 +2008,7 @@ describe('model: querying:', function() {
       Test.create({loc: [35, 50]}, {loc: [-40, -90]}, complete);
 
       function test() {
-        Test.find({loc: {'$within': {'$box': [[30, 40], [40, 60]]}}}, function(err, docs) {
+        Test.find({loc: {$within: {$box: [[30, 40], [40, 60]]}}}, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 1);
           done();
diff --git a/test/model.test.js b/test/model.test.js
index cabd9d2fce0..d4c70756adf 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4071,7 +4071,7 @@ describe('Model', function() {
         }
       }, { autoIndex: false });
 
-      LocationSchema.index({ 'location': '2dsphere' });
+      LocationSchema.index({ location: '2dsphere' });
 
       const Location = db.model('Test', LocationSchema);
 
diff --git a/test/model.translateAliases.test.js b/test/model.translateAliases.test.js
index 1e390bc5b0c..a7807fa16e2 100644
--- a/test/model.translateAliases.test.js
+++ b/test/model.translateAliases.test.js
@@ -27,19 +27,19 @@ describe('model translate aliases', function() {
     assert.deepEqual(
       // Translate aliases
       Character.translateAliases({
-        '_id': '1',
-        '名': 'Stark',
-        '年齢': 30,
+        _id: '1',
+        名: 'Stark',
+        年齢: 30,
         'dot.syntax': 'DotSyntax',
-        '$and': [{'$or': [{'名': 'Stark'}, {'年齢': 30}]}, {'dot.syntax': 'DotSyntax'}]
+        $and: [{$or: [{名: 'Stark'}, {年齢: 30}]}, {'dot.syntax': 'DotSyntax'}]
       }),
       // How translated aliases suppose to look like
       {
         name: 'Stark',
-        '_id': '1',
+        _id: '1',
         'bio.age': 30,
         'd.s': 'DotSyntax',
-        '$and': [{'$or': [{name: 'Stark'}, {'bio.age': 30}]}, {'d.s': 'DotSyntax'}]
+        $and: [{$or: [{name: 'Stark'}, {'bio.age': 30}]}, {'d.s': 'DotSyntax'}]
       }
     );
 
diff --git a/test/model.update.test.js b/test/model.update.test.js
index d2031a3c81e..d869c2b3270 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -241,8 +241,8 @@ describe('model: update:', function() {
   });
 
   it('makes copy of conditions and update options', function(done) {
-    const conditions = {'_id': post._id.toString()};
-    const update = {'$set': {'some_attrib': post._id.toString()}};
+    const conditions = {_id: post._id.toString()};
+    const update = {$set: {some_attrib: post._id.toString()}};
     BlogPost.update(conditions, update, function(err) {
       assert.ifError(err);
       assert.equal(typeof conditions._id, 'string');
@@ -1636,7 +1636,7 @@ describe('model: update:', function() {
 
       Collection.create({}, function(error, doc) {
         assert.ifError(error);
-        const update = { 'field2': { name: 'test' } };
+        const update = { field2: { name: 'test' } };
         Collection.update({ _id: doc._id }, update, function(err) {
           assert.ifError(err);
           Collection.collection.findOne({ _id: doc._id }, function(err, doc) {
@@ -1691,7 +1691,7 @@ describe('model: update:', function() {
         assert.ifError(error);
         const query = { 'regions.r': 'test' };
         const update = { $set: { 'regions.$.action': { order: 'move' } } };
-        const opts = { 'new': true };
+        const opts = { new: true };
         Season.findOneAndUpdate(query, update, opts, function(error, doc) {
           assert.ifError(error);
           assert.equal(doc.toObject().regions[0].action.order, 'move');
@@ -1950,7 +1950,7 @@ describe('model: update:', function() {
       b2.save(function(err, doc) {
         const query = { _id: doc._id };
         const update = { $push: { children: { senderId: '234' } } };
-        const opts = { 'new': true };
+        const opts = { new: true };
         Parent.findOneAndUpdate(query, update, opts).exec(function(error, res) {
           assert.ifError(error);
           assert.equal(res.children.length, 1);
@@ -1993,7 +1993,7 @@ describe('model: update:', function() {
             child: { senderId: '567' }
           }
         };
-        const opts = { 'new': true };
+        const opts = { new: true };
         Parent.findOneAndUpdate(query, update, opts).exec(function(error, res) {
           assert.ifError(error);
           assert.equal(res.children.length, 1);
@@ -3072,7 +3072,7 @@ describe('model: update:', function() {
 
       const cond = { name: 'Xyz' };
       const obj1 = { x: 'Y' };
-      const set = { $set: { 'arr': obj1 } };
+      const set = { $set: { arr: obj1 } };
 
       Test.create(test).
         then(function() {
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 782d42b0485..b4026fb999b 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -131,7 +131,7 @@ describe('Map', function() {
 
       person.fact.delete('killer');
 
-      assert.deepStrictEqual(person.$__delta()[1], { '$unset': { 'fact.killer': 1 } });
+      assert.deepStrictEqual(person.$__delta()[1], { $unset: { 'fact.killer': 1 } });
       assert.deepStrictEqual(Array.from(person.fact.keys()).sort(), ['cool', 'girl']);
       assert.strictEqual(person.fact.get('killer'), undefined);
 
@@ -655,7 +655,7 @@ describe('Map', function() {
     return co(function*() {
       const first = yield Parent.create({
         children: {
-          'one': {name: 'foo'}
+          one: {name: 'foo'}
         }
       });
 

From d5c6f753caea0f059f08d56e8d0e9fc21502d8a3 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 12 Mar 2020 01:40:37 +0200
Subject: [PATCH 0582/2348] Add object-curly-spacing and no-undef

---
 examples/aggregate/aggregate.js               |  12 +-
 examples/doc-methods.js                       |   2 +-
 examples/express/connection-sharing/modelA.js |   2 +-
 examples/express/connection-sharing/routes.js |   2 +-
 examples/geospatial/geoJSONSchema.js          |   4 +-
 examples/geospatial/geoJSONexample.js         |  14 +-
 examples/geospatial/geospatial.js             |   4 +-
 examples/geospatial/person.js                 |   6 +-
 examples/lean/lean.js                         |   2 +-
 .../population-across-three-collections.js    |   6 +-
 examples/population/population-basic.js       |   2 +-
 .../population/population-of-existing-doc.js  |   2 +-
 .../population-of-multiple-existing-docs.js   |   2 +-
 examples/population/population-options.js     |   4 +-
 .../population/population-plain-objects.js    |   2 +-
 examples/promises/promise.js                  |   4 +-
 examples/querybuilder/querybuilder.js         |   2 +-
 examples/replicasets/replica-sets.js          |   4 +-
 examples/schema/schema.js                     |   2 +-
 examples/statics/person.js                    |   2 +-
 examples/statics/statics.js                   |   2 +-
 lib/aggregate.js                              |  14 +-
 lib/collection.js                             |   2 +-
 lib/connection.js                             |   4 +-
 lib/document.js                               |  10 +-
 lib/drivers/node-mongodb-native/collection.js |   4 +-
 lib/helpers/model/discriminator.js            |   4 +-
 lib/helpers/query/castUpdate.js               |   2 +-
 lib/helpers/schema/addAutoId.js               |   2 +-
 lib/helpers/updateValidators.js               |   2 +-
 lib/model.js                                  |  22 +-
 lib/plugins/sharding.js                       |   2 +-
 lib/plugins/validateBeforeSave.js             |   2 +-
 lib/query.js                                  |  14 +-
 lib/schema.js                                 |   6 +-
 lib/schematype.js                             |   6 +-
 lib/types/core_array.js                       |  12 +-
 lib/types/documentarray.js                    |   2 +-
 lib/types/embedded.js                         |   2 +-
 package.json                                  |   2 +
 static.js                                     |   2 +-
 test/aggregate.test.js                        |  12 +-
 test/browser.test.js                          |   6 +-
 test/cast.test.js                             |  54 +-
 test/collection.capped.test.js                |   6 +-
 test/collection.test.js                       |   8 +-
 test/connection.test.js                       |  38 +-
 test/document.isselected.test.js              |  26 +-
 test/document.modified.test.js                |  72 +--
 test/document.populate.test.js                |  92 +--
 test/document.strict.test.js                  |  86 +--
 test/document.test.js                         | 518 ++++++++--------
 test/document.unit.test.js                    |  14 +-
 test/errors.validation.test.js                |  26 +-
 test/gh-1408.test.js                          |  30 +-
 test/helpers/getFunctionName.test.js          |   2 +-
 test/helpers/populate.getSchemaTypes.test.js  |   4 +-
 test/helpers/populate.getVirtual.test.js      |  14 +-
 test/index.test.js                            |  18 +-
 test/model.aggregate.test.js                  |   6 +-
 test/model.create.test.js                     |  22 +-
 test/model.discriminator.querying.test.js     | 216 +++----
 test/model.field.selection.test.js            |  76 +--
 test/model.findOneAndDelete.test.js           |  62 +-
 test/model.findOneAndRemove.test.js           |  62 +-
 test/model.findOneAndReplace.test.js          |  54 +-
 test/model.findOneAndUpdate.test.js           | 388 ++++++------
 test/model.geosearch.test.js                  |  38 +-
 test/model.hydrate.test.js                    |  10 +-
 test/model.indexes.test.js                    |  58 +-
 test/model.mapreduce.test.js                  |  32 +-
 test/model.middleware.test.js                 |   8 +-
 test/model.populate.divergent.test.js         |  32 +-
 test/model.populate.setting.test.js           |  34 +-
 test/model.populate.test.js                   | 470 +++++++--------
 test/model.query.casting.test.js              | 176 +++---
 test/model.querying.test.js                   | 558 +++++++++---------
 test/model.test.js                            | 492 +++++++--------
 test/model.translateAliases.test.js           |   4 +-
 test/model.update.test.js                     | 418 ++++++-------
 test/object.create.null.test.js               |   6 +-
 test/plugin.idGetter.test.js                  |   4 +-
 test/query.middleware.test.js                 |  28 +-
 test/query.test.js                            | 370 ++++++------
 test/query.toconstructor.test.js              |  44 +-
 test/schema.alias.test.js                     |   4 +-
 test/schema.boolean.test.js                   |  10 +-
 test/schema.documentarray.test.js             |  22 +-
 test/schema.mixed.test.js                     |   4 +-
 test/schema.onthefly.test.js                  |  14 +-
 test/schema.select.test.js                    | 100 ++--
 test/schema.singlenestedpath.test.js          |   4 +-
 test/schema.test.js                           |   4 +-
 test/schema.timestamps.test.js                |  36 +-
 test/schema.validation.test.js                | 148 ++---
 test/schematype.test.js                       |  34 +-
 test/shard.test.js                            |  48 +-
 test/types.array.test.js                      | 222 +++----
 test/types.buffer.test.js                     |  46 +-
 test/types.document.test.js                   |  26 +-
 test/types.documentarray.test.js              |  98 +--
 .../types.embeddeddocumentdeclarative.test.js |   4 +-
 test/types.map.test.js                        |   2 +-
 test/types.subdocument.test.js                |   2 +-
 test/updateValidators.unit.test.js            |  10 +-
 test/utils.test.js                            |   8 +-
 test/versioning.test.js                       |  76 +--
 website.js                                    |   2 +-
 108 files changed, 2909 insertions(+), 2907 deletions(-)

diff --git a/examples/aggregate/aggregate.js b/examples/aggregate/aggregate.js
index 4e9de2a669d..59b315425f6 100644
--- a/examples/aggregate/aggregate.js
+++ b/examples/aggregate/aggregate.js
@@ -67,15 +67,15 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
     // framework, see http://docs.mongodb.org/manual/core/aggregation/
     Person.aggregate(
       // select the fields we want to deal with
-      {$project: {name: 1, likes: 1}},
+      { $project: { name: 1, likes: 1 } },
       // unwind 'likes', which will create a document for each like
-      {$unwind: '$likes'},
+      { $unwind: '$likes' },
       // group everything by the like and then add each name with that like to
       // the set for the like
-      {$group: {
-        _id: {likes: '$likes'},
-        likers: {$addToSet: '$name'}
-      }},
+      { $group: {
+        _id: { likes: '$likes' },
+        likers: { $addToSet: '$name' }
+      } },
       function(err, result) {
         if (err) throw err;
         console.log(result);
diff --git a/examples/doc-methods.js b/examples/doc-methods.js
index 51d70489231..52f4f6f2e49 100644
--- a/examples/doc-methods.js
+++ b/examples/doc-methods.js
@@ -58,7 +58,7 @@ mongoose.connect(uri, function(err) {
  */
 
 function example() {
-  Character.create({name: 'Link', health: 100}, function(err, link) {
+  Character.create({ name: 'Link', health: 100 }, function(err, link) {
     if (err) return done(err);
     console.log('found', link);
     link.attack(); // 'Link is attacking'
diff --git a/examples/express/connection-sharing/modelA.js b/examples/express/connection-sharing/modelA.js
index 85b8cc2d7db..b52e20c0420 100644
--- a/examples/express/connection-sharing/modelA.js
+++ b/examples/express/connection-sharing/modelA.js
@@ -1,6 +1,6 @@
 'use strict';
 const Schema = require('../../../lib').Schema;
-const mySchema = Schema({name: String});
+const mySchema = Schema({ name: String });
 
 /* global db */
 module.exports = db.model('MyModel', mySchema);
diff --git a/examples/express/connection-sharing/routes.js b/examples/express/connection-sharing/routes.js
index 231f5fb2c89..28c73dbc972 100644
--- a/examples/express/connection-sharing/routes.js
+++ b/examples/express/connection-sharing/routes.js
@@ -14,7 +14,7 @@ exports.modelName = function(req, res) {
 };
 
 exports.insert = function(req, res, next) {
-  model.create({name: 'inserting ' + Date.now()}, function(err, doc) {
+  model.create({ name: 'inserting ' + Date.now() }, function(err, doc) {
     if (err) return next(err);
     res.send(doc);
   });
diff --git a/examples/geospatial/geoJSONSchema.js b/examples/geospatial/geoJSONSchema.js
index d85a9511220..ae3d10675e2 100644
--- a/examples/geospatial/geoJSONSchema.js
+++ b/examples/geospatial/geoJSONSchema.js
@@ -13,12 +13,12 @@ module.exports = function() {
   // MUST BE VANILLA
   const LocationObject = new Schema({
     loc: {
-      type: {type: String},
+      type: { type: String },
       coordinates: []
     }
   });
   // define the index
-  LocationObject.index({loc: '2dsphere'});
+  LocationObject.index({ loc: '2dsphere' });
 
   mongoose.model('Location', LocationObject);
 };
diff --git a/examples/geospatial/geoJSONexample.js b/examples/geospatial/geoJSONexample.js
index 749dbd9d3ec..6c7507c0876 100644
--- a/examples/geospatial/geoJSONexample.js
+++ b/examples/geospatial/geoJSONexample.js
@@ -13,11 +13,11 @@ const Location = mongoose.model('Location');
 // define some dummy data
 // note: the type can be Point, LineString, or Polygon
 const data = [
-  {loc: {type: 'Point', coordinates: [-20.0, 5.0]}},
-  {loc: {type: 'Point', coordinates: [6.0, 10.0]}},
-  {loc: {type: 'Point', coordinates: [34.0, -50.0]}},
-  {loc: {type: 'Point', coordinates: [-100.0, 70.0]}},
-  {loc: {type: 'Point', coordinates: [38.0, 38.0]}}
+  { loc: { type: 'Point', coordinates: [-20.0, 5.0] } },
+  { loc: { type: 'Point', coordinates: [6.0, 10.0] } },
+  { loc: { type: 'Point', coordinates: [34.0, -50.0] } },
+  { loc: { type: 'Point', coordinates: [-100.0, 70.0] } },
+  { loc: { type: 'Point', coordinates: [38.0, 38.0] } }
 ];
 
 
@@ -38,9 +38,9 @@ mongoose.connect('mongodb://localhost/locations', function(err) {
         throw err;
       }
       // create the location we want to search for
-      const coords = {type: 'Point', coordinates: [-5, 5]};
+      const coords = { type: 'Point', coordinates: [-5, 5] };
       // search for it
-      Location.find({loc: {$near: coords}}).limit(1).exec(function(err, res) {
+      Location.find({ loc: { $near: coords } }).limit(1).exec(function(err, res) {
         if (err) {
           throw err;
         }
diff --git a/examples/geospatial/geospatial.js b/examples/geospatial/geospatial.js
index 6241fdcfc7e..4b5b8705b08 100644
--- a/examples/geospatial/geospatial.js
+++ b/examples/geospatial/geospatial.js
@@ -69,7 +69,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
     }
 
     // let's find the closest person to bob
-    Person.find({name: 'bob'}, function(err, res) {
+    Person.find({ name: 'bob' }, function(err, res) {
       if (err) {
         throw err;
       }
@@ -86,7 +86,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
         // information about geospatial queries and indexes, see
         // http://docs.mongodb.org/manual/applications/geospatial-indexes/
         const coords = [7, 7];
-        Person.find({loc: {$nearSphere: coords}}).limit(1).exec(function(err, res) {
+        Person.find({ loc: { $nearSphere: coords } }).limit(1).exec(function(err, res) {
           console.log('Closest to %s is %s', coords, res);
           cleanup();
         });
diff --git a/examples/geospatial/person.js b/examples/geospatial/person.js
index 1f51af1943c..ccfbce786c8 100644
--- a/examples/geospatial/person.js
+++ b/examples/geospatial/person.js
@@ -14,14 +14,14 @@ module.exports = function() {
     gender: String,
     likes: [String],
     // define the geospatial field
-    loc: {type: [Number], index: '2d'}
+    loc: { type: [Number], index: '2d' }
   });
 
   // define a method to find the closest person
   PersonSchema.methods.findClosest = function(cb) {
     return this.model('Person').find({
-      loc: {$nearSphere: this.loc},
-      name: {$ne: this.name}
+      loc: { $nearSphere: this.loc },
+      name: { $ne: this.name }
     }).limit(1).exec(cb);
   };
 
diff --git a/examples/lean/lean.js b/examples/lean/lean.js
index b244ae02666..f817b1d4f86 100644
--- a/examples/lean/lean.js
+++ b/examples/lean/lean.js
@@ -68,7 +68,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
 
     // when using .lean() the default is true, but you can explicitly set the
     // value by passing in a boolean value. IE. .lean(false)
-    const q = Person.find({age: {$lt: 1000}}).sort('age').limit(2).lean();
+    const q = Person.find({ age: { $lt: 1000 } }).sort('age').limit(2).lean();
     q.exec(function(err, results) {
       if (err) throw err;
       console.log('Are the results MongooseDocuments?: %s', results[0] instanceof mongoose.Document);
diff --git a/examples/population/population-across-three-collections.js b/examples/population/population-across-three-collections.js
index 630ea5f2db3..4ef5e3540cf 100644
--- a/examples/population/population-across-three-collections.js
+++ b/examples/population/population-across-three-collections.js
@@ -99,7 +99,7 @@ mongoose.connection.on('open', function() {
        */
 
       BlogPost
-        .find({tags: 'fun'})
+        .find({ tags: 'fun' })
         .lean()
         .populate('author')
         .exec(function(err, docs) {
@@ -112,13 +112,13 @@ mongoose.connection.on('open', function() {
           const opts = {
             path: 'author.friends',
             select: 'name',
-            options: {limit: 2}
+            options: { limit: 2 }
           };
 
           BlogPost.populate(docs, opts, function(err, docs) {
             assert.ifError(err);
             console.log('populated');
-            const s = require('util').inspect(docs, {depth: null, colors: true});
+            const s = require('util').inspect(docs, { depth: null, colors: true });
             console.log(s);
             done();
           });
diff --git a/examples/population/population-basic.js b/examples/population/population-basic.js
index da1b1cd3f49..9be961713b9 100644
--- a/examples/population/population-basic.js
+++ b/examples/population/population-basic.js
@@ -78,7 +78,7 @@ function createData() {
 
 function example() {
   Game
-    .findOne({name: /^Legend of Zelda/})
+    .findOne({ name: /^Legend of Zelda/ })
     .populate('consoles')
     .exec(function(err, ocinara) {
       if (err) return done(err);
diff --git a/examples/population/population-of-existing-doc.js b/examples/population/population-of-existing-doc.js
index 543a161a9b6..d008f4f313c 100644
--- a/examples/population/population-of-existing-doc.js
+++ b/examples/population/population-of-existing-doc.js
@@ -78,7 +78,7 @@ function createData() {
 
 function example() {
   Game
-    .findOne({name: /^Legend of Zelda/})
+    .findOne({ name: /^Legend of Zelda/ })
     .exec(function(err, ocinara) {
       if (err) return done(err);
 
diff --git a/examples/population/population-of-multiple-existing-docs.js b/examples/population/population-of-multiple-existing-docs.js
index 9e9b99493f6..f070d6cccd8 100644
--- a/examples/population/population-of-multiple-existing-docs.js
+++ b/examples/population/population-of-multiple-existing-docs.js
@@ -97,7 +97,7 @@ function example() {
 
       console.log('found %d games', games.length);
 
-      const options = {path: 'consoles', select: 'name released -_id'};
+      const options = { path: 'consoles', select: 'name released -_id' };
       Game.populate(games, options, function(err, games) {
         if (err) return done(err);
 
diff --git a/examples/population/population-options.js b/examples/population/population-options.js
index ab32e203851..8bd18fa97a7 100644
--- a/examples/population/population-options.js
+++ b/examples/population/population-options.js
@@ -105,9 +105,9 @@ function example() {
     .find({})
     .populate({
       path: 'consoles',
-      match: {manufacturer: 'Nintendo'},
+      match: { manufacturer: 'Nintendo' },
       select: 'name',
-      options: {comment: 'population'}
+      options: { comment: 'population' }
     })
     .exec(function(err, games) {
       if (err) return done(err);
diff --git a/examples/population/population-plain-objects.js b/examples/population/population-plain-objects.js
index aad5fa50e4f..e0fb91cc6fc 100644
--- a/examples/population/population-plain-objects.js
+++ b/examples/population/population-plain-objects.js
@@ -80,7 +80,7 @@ function createData() {
 
 function example() {
   Game
-    .findOne({name: /^Legend of Zelda/})
+    .findOne({ name: /^Legend of Zelda/ })
     .populate('consoles')
     .lean() // just return plain objects, not documents wrapped by mongoose
     .exec(function(err, ocinara) {
diff --git a/examples/promises/promise.js b/examples/promises/promise.js
index ae4ba45a8b9..45f474296a6 100644
--- a/examples/promises/promise.js
+++ b/examples/promises/promise.js
@@ -54,7 +54,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
     }
 
     // create a promise (get one from the query builder)
-    const prom = Person.find({age: {$lt: 1000}}).exec();
+    const prom = Person.find({ age: { $lt: 1000 } }).exec();
 
     // add a callback on the promise. This will be called on both error and
     // complete
@@ -82,7 +82,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
       });
 
       // return the next promise
-      return Person.find({_id: {$nin: ids}}).exec();
+      return Person.find({ _id: { $nin: ids } }).exec();
     }).then(function(oldest) {
       console.log('Oldest person is: %s', oldest);
     }).then(cleanup);
diff --git a/examples/querybuilder/querybuilder.js b/examples/querybuilder/querybuilder.js
index 67fbb79b504..afb3969d830 100644
--- a/examples/querybuilder/querybuilder.js
+++ b/examples/querybuilder/querybuilder.js
@@ -52,7 +52,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
 
     // when querying data, instead of providing a callback, you can instead
     // leave that off and get a query object returned
-    const query = Person.find({age: {$lt: 1000}});
+    const query = Person.find({ age: { $lt: 1000 } });
 
     // this allows you to continue applying modifiers to it
     query.sort('birthday');
diff --git a/examples/replicasets/replica-sets.js b/examples/replicasets/replica-sets.js
index b52298f1619..74217bf113e 100644
--- a/examples/replicasets/replica-sets.js
+++ b/examples/replicasets/replica-sets.js
@@ -44,7 +44,7 @@ const data = [
 // to connect to a replica set, pass in the comma delimited uri and optionally
 // any connection options such as the rs_name.
 const opts = {
-  replSet: {rs_name: 'rs0'}
+  replSet: { rs_name: 'rs0' }
 };
 mongoose.connect('mongodb://localhost:27018/persons,localhost:27019,localhost:27020', opts, function(err) {
   if (err) throw err;
@@ -58,7 +58,7 @@ mongoose.connect('mongodb://localhost:27018/persons,localhost:27019,localhost:27
     }
 
     // create and delete some data
-    const prom = Person.find({age: {$lt: 1000}}).exec();
+    const prom = Person.find({ age: { $lt: 1000 } }).exec();
 
     prom.then(function(people) {
       console.log('young people: %s', people);
diff --git a/examples/schema/schema.js b/examples/schema/schema.js
index dc6e25d35fb..be82788ae59 100644
--- a/examples/schema/schema.js
+++ b/examples/schema/schema.js
@@ -88,7 +88,7 @@ BlogPost.methods.findCreator = function(callback) {
 };
 
 BlogPost.statics.findByTitle = function(title, callback) {
-  return this.find({title: title}, callback);
+  return this.find({ title: title }, callback);
 };
 
 BlogPost.methods.expressiveQuery = function(creator, date, callback) {
diff --git a/examples/statics/person.js b/examples/statics/person.js
index 02987f90a2c..8af10c92c14 100644
--- a/examples/statics/person.js
+++ b/examples/statics/person.js
@@ -15,7 +15,7 @@ module.exports = function() {
 
   // define a static
   PersonSchema.statics.findPersonByName = function(name, cb) {
-    this.find({name: new RegExp(name, 'i')}, cb);
+    this.find({ name: new RegExp(name, 'i') }, cb);
   };
 
   mongoose.model('Person', PersonSchema);
diff --git a/examples/statics/statics.js b/examples/statics/statics.js
index 53a0106debb..3675114c25a 100644
--- a/examples/statics/statics.js
+++ b/examples/statics/statics.js
@@ -15,7 +15,7 @@ mongoose.connect('mongodb://localhost/persons', function(err) {
     throw err;
   }
 
-  Person.create({name: 'bill', age: 25, birthday: new Date().setFullYear((new Date().getFullYear() - 25))},
+  Person.create({ name: 'bill', age: 25, birthday: new Date().setFullYear((new Date().getFullYear() - 25)) },
     function(err, bill) {
       if (err) {
         throw err;
diff --git a/lib/aggregate.js b/lib/aggregate.js
index 53ffa5cad4b..abc51db118b 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -178,7 +178,7 @@ Aggregate.prototype.addFields = function(arg) {
   } else {
     throw new Error('Invalid addFields() argument. Must be an object');
   }
-  return this.append({$addFields: fields});
+  return this.append({ $addFields: fields });
 };
 
 /**
@@ -235,7 +235,7 @@ Aggregate.prototype.project = function(arg) {
     throw new Error('Invalid project() argument. Must be string or object');
   }
 
-  return this.append({$project: fields});
+  return this.append({ $project: fields });
 };
 
 /**
@@ -484,7 +484,7 @@ Aggregate.prototype.sortByCount = function(arg) {
  */
 
 Aggregate.prototype.lookup = function(options) {
-  return this.append({$lookup: options});
+  return this.append({ $lookup: options });
 };
 
 /**
@@ -536,7 +536,7 @@ Aggregate.prototype.graphLookup = function(options) {
  */
 
 Aggregate.prototype.sample = function(size) {
-  return this.append({$sample: {size: size}});
+  return this.append({ $sample: { size: size } });
 };
 
 /**
@@ -588,7 +588,7 @@ Aggregate.prototype.sort = function(arg) {
     throw new TypeError('Invalid sort() argument. Must be a string or object.');
   }
 
-  return this.append({$sort: sort});
+  return this.append({ $sort: sort });
 };
 
 /**
@@ -684,7 +684,7 @@ Aggregate.prototype.redact = function(expression, thenExpr, elseExpr) {
     throw new TypeError('Invalid arguments');
   }
 
-  return this.append({$redact: expression});
+  return this.append({ $redact: expression });
 };
 
 /**
@@ -907,7 +907,7 @@ Aggregate.prototype.collation = function(collation) {
  */
 
 Aggregate.prototype.facet = function(options) {
-  return this.append({$facet: options});
+  return this.append({ $facet: options });
 };
 
 /**
diff --git a/lib/collection.js b/lib/collection.js
index 1f797058b44..ff024265219 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -32,7 +32,7 @@ function Collection(name, conn, opts) {
     : opts.bufferCommands;
 
   if (typeof opts.capped === 'number') {
-    opts.capped = {size: opts.capped};
+    opts.capped = { size: opts.capped };
   }
 
   this.opts = opts;
diff --git a/lib/connection.js b/lib/connection.js
index abd32f39c72..513bbe1281e 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -57,7 +57,7 @@ function Connection(base) {
   this.base = base;
   this.collections = {};
   this.models = {};
-  this.config = {autoIndex: true};
+  this.config = { autoIndex: true };
   this.replica = false;
   this.options = null;
   this.otherDbs = []; // FIXME: To be replaced with relatedDbs
@@ -1043,7 +1043,7 @@ Connection.prototype.model = function(name, schema, collection) {
     return this.models[name];
   }
 
-  const opts = {cache: false, connection: this};
+  const opts = { cache: false, connection: this };
   let model;
 
   if (schema && schema.instanceOfSchema) {
diff --git a/lib/document.js b/lib/document.js
index f4e69050c07..b81e45b1c71 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -687,7 +687,7 @@ function init(self, obj, doc, opts, prefix) {
 
 Document.prototype.update = function update() {
   const args = utils.args(arguments);
-  args.unshift({_id: this._id});
+  args.unshift({ _id: this._id });
   const query = this.constructor.update.apply(this.constructor, args);
 
   if (this.$session() != null) {
@@ -725,7 +725,7 @@ Document.prototype.update = function update() {
  */
 
 Document.prototype.updateOne = function updateOne(doc, options, callback) {
-  const query = this.constructor.updateOne({_id: this._id}, doc, options);
+  const query = this.constructor.updateOne({ _id: this._id }, doc, options);
   query._pre(cb => {
     this.constructor._middleware.execPre('updateOne', this, [this], cb);
   });
@@ -971,7 +971,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
         this.$set(prefix + key, p, constructing, options);
       } else if (pathtype === 'nested' && path[key] instanceof Document) {
         this.$set(prefix + key,
-          path[key].toObject({transform: false}), constructing, options);
+          path[key].toObject({ transform: false }), constructing, options);
       } else if (strict === 'throw') {
         if (pathtype === 'nested') {
           throw new ObjectExpectedError(key, path[key]);
@@ -2071,7 +2071,7 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
       conflictStack: this.$__.validating.stack
     });
   } else {
-    this.$__.validating = new ParallelValidateError(this, {parentStack: options && options.parentStack});
+    this.$__.validating = new ParallelValidateError(this, { parentStack: options && options.parentStack });
   }
 
   if (typeof pathsToValidate === 'function') {
@@ -3665,7 +3665,7 @@ Document.prototype.populated = function(path, val, options) {
   }
 
   this.$__.populated || (this.$__.populated = {});
-  this.$__.populated[path] = {value: val, options: options};
+  this.$__.populated[path] = { value: val, options: options };
 
   // If this was a nested populate, make sure each populated doc knows
   // about its populated children (gh-7685)
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 7351ebe0d64..7f0be874031 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -61,7 +61,7 @@ NativeCollection.prototype.onOpen = function() {
     if (err) return callback(err);
 
     // discover if this collection exists and if it is capped
-    _this.conn.db.listCollections({name: _this.name}).toArray(function(err, docs) {
+    _this.conn.db.listCollections({ name: _this.name }).toArray(function(err, docs) {
       if (err) {
         return callback(err);
       }
@@ -282,7 +282,7 @@ function format(obj, sub, color) {
   }
 
   const clone = require('../../helpers/clone');
-  let x = clone(obj, {transform: false});
+  let x = clone(obj, { transform: false });
 
   if (x.constructor.name === 'Binary') {
     x = 'BinData(' + x.sub_type + ', "' + x.toString('base64') + '")';
diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index 11867d34da5..51c7cc0b7aa 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -120,7 +120,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
       existingPath.instance :
       String;
     schema.add(obj);
-    schema.discriminatorMapping = {key: key, value: value, isRoot: false};
+    schema.discriminatorMapping = { key: key, value: value, isRoot: false };
 
     if (baseSchema.options.collection) {
       schema.options.collection = baseSchema.options.collection;
@@ -168,7 +168,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
   }
 
   if (!model.schema.discriminatorMapping) {
-    model.schema.discriminatorMapping = {key: key, value: null, isRoot: true};
+    model.schema.discriminatorMapping = { key: key, value: null, isRoot: true };
   }
   if (!model.schema.discriminators) {
     model.schema.discriminators = {};
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 01114523512..bdad8044558 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -498,7 +498,7 @@ function castUpdateVal(schema, val, op, $conditional, context, path) {
   }
   if (op === '$currentDate') {
     if (typeof val === 'object') {
-      return {$type: val.$type};
+      return { $type: val.$type };
     }
     return Boolean(val);
   }
diff --git a/lib/helpers/schema/addAutoId.js b/lib/helpers/schema/addAutoId.js
index 898863963db..11a1f2302e4 100644
--- a/lib/helpers/schema/addAutoId.js
+++ b/lib/helpers/schema/addAutoId.js
@@ -1,7 +1,7 @@
 'use strict';
 
 module.exports = function addAutoId(schema) {
-  const _obj = {_id: {auto: true}};
+  const _obj = { _id: { auto: true } };
   _obj._id[schema.options.typeKey] = 'ObjectId';
   schema.add(_obj);
 };
\ No newline at end of file
diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index de8b027bb9f..5f29e02ba68 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -109,7 +109,7 @@ module.exports = function(query, schema, castedDoc, options, callback) {
               callback(null);
             },
             context,
-            {updateValidator: true});
+            { updateValidator: true });
         });
       });
     } else {
diff --git a/lib/model.js b/lib/model.js
index 0d62ee723a7..30b27d2e0e6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -607,7 +607,7 @@ function handleAtomics(self, where, delta, data, value) {
     // $set
 
     if (utils.isMongooseObject(value)) {
-      value = value.toObject({depopulate: 1, _isNested: true});
+      value = value.toObject({ depopulate: 1, _isNested: true });
     } else if (value.valueOf) {
       value = value.valueOf();
     }
@@ -617,7 +617,7 @@ function handleAtomics(self, where, delta, data, value) {
 
   function iter(mem) {
     return utils.isMongooseObject(mem)
-      ? mem.toObject({depopulate: 1, _isNested: true})
+      ? mem.toObject({ depopulate: 1, _isNested: true })
       : mem;
   }
 
@@ -626,7 +626,7 @@ function handleAtomics(self, where, delta, data, value) {
     val = atomics[op];
 
     if (utils.isMongooseObject(val)) {
-      val = val.toObject({depopulate: true, transform: false, _isNested: true});
+      val = val.toObject({ depopulate: true, transform: false, _isNested: true });
     } else if (Array.isArray(val)) {
       val = val.map(iter);
     } else if (val.valueOf) {
@@ -634,7 +634,7 @@ function handleAtomics(self, where, delta, data, value) {
     }
 
     if (op === '$addToSet') {
-      val = {$each: val};
+      val = { $each: val };
     }
 
     operand(self, where, delta, data, val, op);
@@ -2135,7 +2135,7 @@ Model.findById = function findById(id, projection, options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return this.findOne({_id: id}, projection, options, callback);
+  return this.findOne({ _id: id }, projection, options, callback);
 };
 
 /**
@@ -2635,7 +2635,7 @@ Model.findByIdAndUpdate = function(id, update, options, callback) {
           + '  ' + this.modelName + '.findByIdAndUpdate()\n';
       throw new TypeError(msg);
     }
-    return this.findOneAndUpdate({_id: id}, undefined);
+    return this.findOneAndUpdate({ _id: id }, undefined);
   }
 
   // if a model is passed in instead of an id
@@ -2643,7 +2643,7 @@ Model.findByIdAndUpdate = function(id, update, options, callback) {
     id = id._id;
   }
 
-  return this.findOneAndUpdate.call(this, {_id: id}, update, options, callback);
+  return this.findOneAndUpdate.call(this, { _id: id }, update, options, callback);
 };
 
 /**
@@ -2767,7 +2767,7 @@ Model.findByIdAndDelete = function(id, options, callback) {
   }
   callback = this.$handleCallbackError(callback);
 
-  return this.findOneAndDelete({_id: id}, options, callback);
+  return this.findOneAndDelete({ _id: id }, options, callback);
 };
 
 /**
@@ -2984,7 +2984,7 @@ Model.findByIdAndRemove = function(id, options, callback) {
   }
   callback = this.$handleCallbackError(callback);
 
-  return this.findOneAndRemove({_id: id}, options, callback);
+  return this.findOneAndRemove({ _id: id }, options, callback);
 };
 
 /**
@@ -3857,11 +3857,11 @@ Model.mapReduce = function mapReduce(o, callback) {
     cb = this.$wrapCallback(cb);
 
     if (!Model.mapReduce.schema) {
-      const opts = {noId: true, noVirtualId: true, strict: false};
+      const opts = { noId: true, noVirtualId: true, strict: false };
       Model.mapReduce.schema = new Schema({}, opts);
     }
 
-    if (!o.out) o.out = {inline: 1};
+    if (!o.out) o.out = { inline: 1 };
     if (o.verbose !== false) o.verbose = true;
 
     o.map = String(o.map);
diff --git a/lib/plugins/sharding.js b/lib/plugins/sharding.js
index 4b3d832c20c..560053ed30c 100644
--- a/lib/plugins/sharding.js
+++ b/lib/plugins/sharding.js
@@ -71,7 +71,7 @@ function storeShard() {
     if (val == null) {
       orig[paths[i]] = val;
     } else if (utils.isMongooseObject(val)) {
-      orig[paths[i]] = val.toObject({depopulate: true, _isNested: true});
+      orig[paths[i]] = val.toObject({ depopulate: true, _isNested: true });
     } else if (val instanceof Date || val[objectIdSymbol]) {
       orig[paths[i]] = val;
     } else if (typeof val.valueOf === 'function') {
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index a486ca2c854..4635de1ccfb 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -30,7 +30,7 @@ module.exports = function(schema) {
           (typeof options === 'object') &&
           ('validateModifiedOnly' in options);
       const validateOptions = hasValidateModifiedOnlyOption ?
-        {validateModifiedOnly: options.validateModifiedOnly} :
+        { validateModifiedOnly: options.validateModifiedOnly } :
         null;
       this.validate(validateOptions, function(error) {
         return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
diff --git a/lib/query.js b/lib/query.js
index 7eac97cda98..cefd977fad9 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2835,7 +2835,7 @@ Query.prototype._deleteMany = wrapThunk(function(callback) {
 
 function completeOne(model, doc, res, options, fields, userProvidedFields, pop, callback) {
   const opts = pop ?
-    {populated: pop}
+    { populated: pop }
     : undefined;
 
   if (options.rawResult && doc == null) {
@@ -3477,7 +3477,7 @@ Query.prototype._findAndModify = function(type, callback) {
           // still need to do the upsert to empty doc
           const doc = utils.clone(castedQuery);
           delete doc._id;
-          this._update = {$set: doc};
+          this._update = { $set: doc };
         } else {
           this.findOne(callback);
           return this;
@@ -4153,7 +4153,7 @@ function _update(query, op, filter, doc, options, callback) {
   if (oldCb) {
     if (typeof oldCb === 'function') {
       callback = function(error, result) {
-        oldCb(error, result ? result.result : {ok: 0, n: 0, nModified: 0});
+        oldCb(error, result ? result.result : { ok: 0, n: 0, nModified: 0 });
       };
     } else {
       throw new Error('Invalid callback() argument.');
@@ -5015,7 +5015,7 @@ Query.prototype.near = function() {
 
   if (arguments.length === 1) {
     if (Array.isArray(arguments[0])) {
-      params.push({center: arguments[0], spherical: sphere});
+      params.push({ center: arguments[0], spherical: sphere });
     } else if (typeof arguments[0] === 'string') {
       // just passing a path
       params.push(arguments[0]);
@@ -5029,10 +5029,10 @@ Query.prototype.near = function() {
     }
   } else if (arguments.length === 2) {
     if (typeof arguments[0] === 'number' && typeof arguments[1] === 'number') {
-      params.push({center: [arguments[0], arguments[1]], spherical: sphere});
+      params.push({ center: [arguments[0], arguments[1]], spherical: sphere });
     } else if (typeof arguments[0] === 'string' && Array.isArray(arguments[1])) {
       params.push(arguments[0]);
-      params.push({center: arguments[1], spherical: sphere});
+      params.push({ center: arguments[1], spherical: sphere });
     } else if (typeof arguments[0] === 'string' && utils.isObject(arguments[1])) {
       params.push(arguments[0]);
       if (typeof arguments[1].spherical !== 'boolean') {
@@ -5046,7 +5046,7 @@ Query.prototype.near = function() {
     if (typeof arguments[0] === 'string' && typeof arguments[1] === 'number'
         && typeof arguments[2] === 'number') {
       params.push(arguments[0]);
-      params.push({center: [arguments[1], arguments[2]], spherical: sphere});
+      params.push({ center: [arguments[1], arguments[2]], spherical: sphere });
     } else {
       throw new TypeError('invalid argument');
     }
diff --git a/lib/schema.js b/lib/schema.js
index 77718b0b9e2..16b0ad46654 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -387,7 +387,7 @@ Schema.prototype.pick = function(paths, options) {
 
 Schema.prototype.defaultOptions = function(options) {
   if (options && options.safe === false) {
-    options.safe = {w: 0};
+    options.safe = { w: 0 };
   }
 
   if (options && options.safe && options.safe.w === 0) {
@@ -923,7 +923,7 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         // The `minimize` and `typeKey` options propagate to child schemas
         // declared inline, like `{ arr: [{ val: { $type: String } }] }`.
         // See gh-3560
-        const childSchemaOptions = {minimize: options.minimize};
+        const childSchemaOptions = { minimize: options.minimize };
         if (options.typeKey) {
           childSchemaOptions.typeKey = options.typeKey;
         }
@@ -1659,7 +1659,7 @@ const safeDeprecationWarning = 'Mongoose: The `safe` option for schemas is ' +
 
 const setSafe = util.deprecate(function setSafe(options, value) {
   options.safe = value === false ?
-    {w: 0} :
+    { w: 0 } :
     value;
 }, safeDeprecationWarning);
 
diff --git a/lib/schematype.js b/lib/schematype.js
index 94b3befcfd1..c1e197b4374 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -310,7 +310,7 @@ SchemaType.prototype.unique = function(bool) {
   if (this._index == null || this._index === true) {
     this._index = {};
   } else if (typeof this._index === 'string') {
-    this._index = {type: this._index};
+    this._index = { type: this._index };
   }
 
   this._index.unique = bool;
@@ -342,7 +342,7 @@ SchemaType.prototype.text = function(bool) {
     typeof this._index === 'boolean') {
     this._index = {};
   } else if (typeof this._index === 'string') {
-    this._index = {type: this._index};
+    this._index = { type: this._index };
   }
 
   this._index.text = bool;
@@ -374,7 +374,7 @@ SchemaType.prototype.sparse = function(bool) {
   if (this._index == null || typeof this._index === 'boolean') {
     this._index = {};
   } else if (typeof this._index === 'string') {
-    this._index = {type: this._index};
+    this._index = { type: this._index };
   }
 
   this._index.sparse = bool;
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index d09bd8c715e..081e54ffe5f 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -79,7 +79,7 @@ class CoreMongooseArray extends Array {
       }
 
       if (op === '$addToSet') {
-        val = {$each: val};
+        val = { $each: val };
       }
 
       ret.push([op, val]);
@@ -242,7 +242,7 @@ class CoreMongooseArray extends Array {
       // non-objects are to be interpreted as _id
       if (Buffer.isBuffer(value) ||
           value instanceof ObjectId || !utils.isObject(value)) {
-        value = {_id: value};
+        value = { _id: value };
       }
 
       // gh-2399
@@ -320,7 +320,7 @@ class CoreMongooseArray extends Array {
     if (op === '$set') {
       // $set takes precedence over all other ops.
       // mark entire array modified.
-      this[arrayAtomicsSymbol] = {$set: val};
+      this[arrayAtomicsSymbol] = { $set: val };
       cleanModifiedSubpaths(this[arrayParentSymbol], this[arrayPathSymbol]);
       this._markModified();
       return this;
@@ -342,7 +342,7 @@ class CoreMongooseArray extends Array {
         Object.keys(atomics).length && !(op in atomics)) {
       // a different op was previously registered.
       // save the entire thing.
-      this[arrayAtomicsSymbol] = {$set: this};
+      this[arrayAtomicsSymbol] = { $set: this };
       return this;
     }
 
@@ -356,10 +356,10 @@ class CoreMongooseArray extends Array {
       if (val[0] instanceof EmbeddedDocument) {
         selector = pullOp['$or'] || (pullOp['$or'] = []);
         Array.prototype.push.apply(selector, val.map(function(v) {
-          return v.toObject({transform: false, virtuals: false});
+          return v.toObject({ transform: false, virtuals: false });
         }));
       } else {
-        selector = pullOp['_id'] || (pullOp['_id'] = {$in: []});
+        selector = pullOp['_id'] || (pullOp['_id'] = { $in: [] });
         selector['$in'] = selector['$in'].concat(val);
       }
     } else if (op === '$push') {
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index c85d98fbfa1..2ad3a457687 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -84,7 +84,7 @@ class CoreDocumentArray extends CoreMongooseArray {
     // non-objects are to be interpreted as _id
     if (Buffer.isBuffer(value) ||
         value instanceof ObjectId || !utils.isObject(value)) {
-      value = {_id: value};
+      value = { _id: value };
     }
 
     if (value &&
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 0201d7660a8..5e817bf0803 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -223,7 +223,7 @@ EmbeddedDocument.prototype.remove = function(options, fn) {
       throw new Error('For your own good, Mongoose does not know ' +
           'how to remove an EmbeddedDocument that has no _id');
     }
-    this.__parentArray.pull({_id: _id});
+    this.__parentArray.pull({ _id: _id });
     this.willRemove = true;
     registerRemoveListener(this);
   }
diff --git a/package.json b/package.json
index 90c216f9fd2..46e5df0c830 100644
--- a/package.json
+++ b/package.json
@@ -131,6 +131,7 @@
       "no-constant-condition": "off",
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",
+      "no-undef": "error",
       "key-spacing": [2, {
         "beforeColon": false,
         "afterColon": true
@@ -140,6 +141,7 @@
         "after": true
       }],
       "array-bracket-spacing": 1,
+      "object-curly-spacing": [2, "always"],
       "comma-dangle": [2, "never"],
       "no-unreachable": 2,
       "quotes": [
diff --git a/static.js b/static.js
index 940170b2c06..78e5d71b601 100644
--- a/static.js
+++ b/static.js
@@ -1,7 +1,7 @@
 'use strict';
 
 const nodeStatic = require('node-static');
-const server = new nodeStatic.Server('.', {cache: 0});
+const server = new nodeStatic.Server('.', { cache: 0 });
 
 require('http').createServer(function(req, res) {
   if (req.url === '/favicon.ico') {
diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index dcd28155bb4..1ae26845c02 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -495,8 +495,8 @@ describe('aggregate: ', function() {
         assert.equal(aggregate.addFields({ a: 1, b: 1, c: 0 }), aggregate);
         assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }]);
 
-        aggregate.addFields({ d: {$add: ['$a', '$b']} });
-        assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }, { $addFields: { d: {$add: ['$a', '$b']} } }]);
+        aggregate.addFields({ d: { $add: ['$a', '$b'] } });
+        assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }, { $addFields: { d: { $add: ['$a', '$b'] } } }]);
         done();
       });
     });
@@ -555,7 +555,7 @@ describe('aggregate: ', function() {
         aggregate.replaceRoot('myNewRoot');
 
         assert.deepEqual(aggregate._pipeline,
-          [{ $replaceRoot: { newRoot: '$myNewRoot' }}]);
+          [{ $replaceRoot: { newRoot: '$myNewRoot' } }]);
         done();
       });
       it('works with an object (gh-6474)', function(done) {
@@ -596,7 +596,7 @@ describe('aggregate: ', function() {
         aggregate.sortByCount({ lname: '$employee.last' });
 
         assert.deepEqual(aggregate._pipeline,
-          [{ $sortByCount: { lname: '$employee.last' }}]);
+          [{ $sortByCount: { lname: '$employee.last' } }]);
         done();
       });
 
@@ -778,7 +778,7 @@ describe('aggregate: ', function() {
             connectToField: 'name',
             as: 'employeeHierarchy'
           }).
-          sort({name: 1}).
+          sort({ name: 1 }).
           exec(function(err, docs) {
             if (err) {
               return done(err);
@@ -969,7 +969,7 @@ describe('aggregate: ', function() {
         assert.equal(aggregate.options.readPreference.mode, pref);
         if (mongo26_or_greater) {
           aggregate.allowDiskUse(true);
-          aggregate.option({maxTimeMS: 1000});
+          aggregate.option({ maxTimeMS: 1000 });
           assert.equal(aggregate.options.allowDiskUse, true);
           assert.equal(aggregate.options.maxTimeMS, 1000);
         }
diff --git a/test/browser.test.js b/test/browser.test.js
index 718fb2e867b..fb0a5d260bc 100644
--- a/test/browser.test.js
+++ b/test/browser.test.js
@@ -24,9 +24,9 @@ describe('browser', function() {
 
   it('document works (gh-4987)', function(done) {
     const schema = new Schema({
-      name: {type: String, required: true},
-      quest: {type: String, match: /Holy Grail/i, required: true},
-      favoriteColor: {type: String, enum: ['Red', 'Blue'], required: true}
+      name: { type: String, required: true },
+      quest: { type: String, match: /Holy Grail/i, required: true },
+      favoriteColor: { type: String, enum: ['Red', 'Blue'], required: true }
     });
 
     new Document({}, schema);
diff --git a/test/cast.test.js b/test/cast.test.js
index 7716f0b1120..ebc8a4b6f58 100644
--- a/test/cast.test.js
+++ b/test/cast.test.js
@@ -15,46 +15,46 @@ const Buffer = require('safe-buffer').Buffer;
 describe('cast: ', function() {
   describe('when casting an array', function() {
     it('casts array with ObjectIds to $in query', function(done) {
-      const schema = new Schema({x: Schema.Types.ObjectId});
+      const schema = new Schema({ x: Schema.Types.ObjectId });
       const ids = [new ObjectId(), new ObjectId()];
-      assert.deepEqual(cast(schema, {x: ids}), { x: { $in: ids } });
+      assert.deepEqual(cast(schema, { x: ids }), { x: { $in: ids } });
       done();
     });
 
     it('casts array with ObjectIds to $in query when values are strings', function(done) {
-      const schema = new Schema({x: Schema.Types.ObjectId});
+      const schema = new Schema({ x: Schema.Types.ObjectId });
       const ids = [new ObjectId(), new ObjectId()];
-      assert.deepEqual(cast(schema, {x: ids.map(String)}), { x: { $in: ids } });
+      assert.deepEqual(cast(schema, { x: ids.map(String) }), { x: { $in: ids } });
       done();
     });
 
     it('throws when ObjectIds not valid', function(done) {
-      const schema = new Schema({x: Schema.Types.ObjectId});
+      const schema = new Schema({ x: Schema.Types.ObjectId });
       const ids = [123, 456, 'asfds'];
       assert.throws(function() {
-        cast(schema, {x: ids});
+        cast(schema, { x: ids });
       }, /Cast to ObjectId failed/);
       done();
     });
 
     it('casts array with Strings to $in query', function(done) {
-      const schema = new Schema({x: String});
+      const schema = new Schema({ x: String });
       const strings = ['bleep', 'bloop'];
-      assert.deepEqual(cast(schema, {x: strings}), { x: { $in: strings } });
+      assert.deepEqual(cast(schema, { x: strings }), { x: { $in: strings } });
       done();
     });
 
     it('casts array with Strings when necessary', function(done) {
-      const schema = new Schema({x: String});
+      const schema = new Schema({ x: String });
       const strings = [123, 456];
-      assert.deepEqual(cast(schema, {x: strings}), { x: { $in: strings.map(String) } });
+      assert.deepEqual(cast(schema, { x: strings }), { x: { $in: strings.map(String) } });
       done();
     });
 
     it('casts array with Numbers to $in query', function(done) {
-      const schema = new Schema({x: Number});
+      const schema = new Schema({ x: Number });
       const numbers = [42, 25];
-      assert.deepEqual(cast(schema, {x: numbers}), { x: { $in: numbers } });
+      assert.deepEqual(cast(schema, { x: numbers }), { x: { $in: numbers } });
       done();
     });
 
@@ -77,17 +77,17 @@ describe('cast: ', function() {
     });
 
     it('casts array with Numbers to $in query when values are strings', function(done) {
-      const schema = new Schema({x: Number});
+      const schema = new Schema({ x: Number });
       const numbers = ['42', '25'];
-      assert.deepEqual(cast(schema, {x: numbers}), { x: { $in: numbers.map(Number) } });
+      assert.deepEqual(cast(schema, { x: numbers }), { x: { $in: numbers.map(Number) } });
       done();
     });
 
     it('throws when Numbers are not valid', function(done) {
-      const schema = new Schema({x: Number});
+      const schema = new Schema({ x: Number });
       const numbers = [123, 456, 'asfds'];
       assert.throws(function() {
-        cast(schema, {x: numbers});
+        cast(schema, { x: numbers });
       }, /Cast to number failed for value "asfds"/);
       done();
     });
@@ -95,30 +95,30 @@ describe('cast: ', function() {
 
   describe('bitwise query operators: ', function() {
     it('with a number', function(done) {
-      const schema = new Schema({x: Buffer});
-      assert.deepEqual(cast(schema, {x: {$bitsAllClear: 3}}),
-        {x: {$bitsAllClear: 3}});
+      const schema = new Schema({ x: Buffer });
+      assert.deepEqual(cast(schema, { x: { $bitsAllClear: 3 } }),
+        { x: { $bitsAllClear: 3 } });
       done();
     });
 
     it('with an array', function(done) {
-      const schema = new Schema({x: Buffer});
-      assert.deepEqual(cast(schema, {x: {$bitsAllSet: [2, '3']}}),
-        {x: {$bitsAllSet: [2, 3]}});
+      const schema = new Schema({ x: Buffer });
+      assert.deepEqual(cast(schema, { x: { $bitsAllSet: [2, '3'] } }),
+        { x: { $bitsAllSet: [2, 3] } });
       done();
     });
 
     it('with a buffer', function(done) {
-      const schema = new Schema({x: Number});
-      assert.deepEqual(cast(schema, {x: {$bitsAnyClear: Buffer.from([3])}}),
-        {x: {$bitsAnyClear: Buffer.from([3])}});
+      const schema = new Schema({ x: Number });
+      assert.deepEqual(cast(schema, { x: { $bitsAnyClear: Buffer.from([3]) } }),
+        { x: { $bitsAnyClear: Buffer.from([3]) } });
       done();
     });
 
     it('throws when invalid', function(done) {
-      const schema = new Schema({x: Number});
+      const schema = new Schema({ x: Number });
       assert.throws(function() {
-        cast(schema, {x: {$bitsAnySet: 'Not a number'}});
+        cast(schema, { x: { $bitsAnySet: 'Not a number' } });
       }, /Cast to number failed/);
       done();
     });
diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index cac4eedfeea..86d9d8b0c71 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -16,8 +16,8 @@ const Schema = mongoose.Schema;
 /**
  * setup
  */
-const capped = new Schema({key: 'string', val: 'number'});
-capped.set('capped', {size: 1000});
+const capped = new Schema({ key: 'string', val: 'number' });
+capped.set('capped', { size: 1000 });
 const coll = 'capped_' + random();
 
 /**
@@ -57,7 +57,7 @@ describe('collections: capped:', function() {
     });
   });
   it('creation using a number', function(done) {
-    const schema = new Schema({key: 'string'}, {capped: 8192});
+    const schema = new Schema({ key: 'string' }, { capped: 8192 });
     const Capped = db.model('Capped3', schema);
     Capped.collection.options(function(err, options) {
       assert.ifError(err);
diff --git a/test/collection.test.js b/test/collection.test.js
index 47587200c7c..79ac6adf822 100644
--- a/test/collection.test.js
+++ b/test/collection.test.js
@@ -21,14 +21,14 @@ describe('collections:', function() {
       }
       assert.ok(connected);
       assert.ok(insertedId !== undefined);
-      collection.findOne({_id: insertedId}).then(doc => {
+      collection.findOne({ _id: insertedId }).then(doc => {
         assert.strictEqual(doc.foo, 'bar');
         db.close();
         done();
       });
     }
 
-    collection.insertOne({foo: 'bar'}, {}, function(err, result) {
+    collection.insertOne({ foo: 'bar' }, {}, function(err, result) {
       assert.ok(connected);
       insertedId = result.insertedId;
       finish();
@@ -45,9 +45,9 @@ describe('collections:', function() {
     const db = mongoose.createConnection();
     const collection = db.collection('gh7676');
 
-    const promise = collection.insertOne({foo: 'bar'}, {})
+    const promise = collection.insertOne({ foo: 'bar' }, {})
       .then(result =>
-        collection.findOne({_id: result.insertedId})
+        collection.findOne({ _id: result.insertedId })
       ).then(doc => {
         assert.strictEqual(doc.foo, 'bar');
       });
diff --git a/test/connection.test.js b/test/connection.test.js
index 10dd4975629..759aa8a0839 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -561,14 +561,14 @@ describe('connections:', function() {
       assert.ok(MyModel.schema instanceof Schema);
       assert.ok(MyModel.prototype.schema instanceof Schema);
 
-      const m = new MyModel({name: 'aaron'});
+      const m = new MyModel({ name: 'aaron' });
       assert.equal(m.name, 'aaron');
       done();
     });
 
     it('should properly assign the db', function(done) {
-      const A = mongoose.model('testing853a', new Schema({x: String}), 'testing853-1');
-      const B = mongoose.model('testing853b', new Schema({x: String}), 'testing853-2');
+      const A = mongoose.model('testing853a', new Schema({ x: String }), 'testing853-1');
+      const B = mongoose.model('testing853b', new Schema({ x: String }), 'testing853-2');
       const C = B.model('testing853a');
       assert.ok(C === A);
       done();
@@ -604,8 +604,8 @@ describe('connections:', function() {
     });
 
     it('uses the passed schema when global model exists with same name (gh-1209)', function(done) {
-      const s1 = new Schema({one: String});
-      const s2 = new Schema({two: Number});
+      const s1 = new Schema({ one: String });
+      const s2 = new Schema({ two: Number });
 
       const db = start();
 
@@ -629,7 +629,7 @@ describe('connections:', function() {
 
     describe('get existing model with not existing collection in db', function() {
       it('must return exiting collection with all collection options', function(done) {
-        mongoose.model('some-th-1458', new Schema({test: String}, {capped: {size: 1000, max: 10}}));
+        mongoose.model('some-th-1458', new Schema({ test: String }, { capped: { size: 1000, max: 10 } }));
         const m = db.model('some-th-1458');
         assert.equal(1000, m.collection.opts.capped.size);
         assert.equal(10, m.collection.opts.capped.max);
@@ -640,7 +640,7 @@ describe('connections:', function() {
     describe('passing collection name', function() {
       describe('when model name already exists', function() {
         it('returns a new uncached model', function(done) {
-          const s1 = new Schema({a: []});
+          const s1 = new Schema({ a: [] });
           const name = 'non-cached-collection-name';
           const A = db.model(name, s1);
           const B = db.model(name);
@@ -656,8 +656,8 @@ describe('connections:', function() {
 
     describe('passing object literal schemas', function() {
       it('works', function(done) {
-        const A = db.model('A', {n: [{age: 'number'}]});
-        const a = new A({n: [{age: '47'}]});
+        const A = db.model('A', { n: [{ age: 'number' }] });
+        const a = new A({ n: [{ age: '47' }] });
         assert.strictEqual(47, a.n[0].age);
         a.save(function(err) {
           assert.ifError(err);
@@ -677,7 +677,7 @@ describe('connections:', function() {
     const coll = db.collection('Test');
     db.then(function() {
       setTimeout(function() {
-        coll.insertOne({x: 1}, function(error) {
+        coll.insertOne({ x: 1 }, function(error) {
           assert.ok(error);
           done();
         });
@@ -703,7 +703,7 @@ describe('connections:', function() {
 
         let threw = false;
         try {
-          db.collection('Test').insertOne({x: 1});
+          db.collection('Test').insertOne({ x: 1 });
         } catch (error) {
           threw = true;
           assert.ok(error);
@@ -777,12 +777,12 @@ describe('connections:', function() {
   describe('modelNames()', function() {
     it('returns names of all models registered on it', function(done) {
       const m = new mongoose.Mongoose;
-      m.model('root', {x: String});
-      const another = m.model('another', {x: String});
-      another.discriminator('discriminated', new Schema({x: String}));
+      m.model('root', { x: String });
+      const another = m.model('another', { x: String });
+      another.discriminator('discriminated', new Schema({ x: String }));
 
       const db = m.createConnection();
-      db.model('something', {x: String});
+      db.model('something', { x: String });
 
       let names = db.modelNames();
       assert.ok(Array.isArray(names));
@@ -833,9 +833,9 @@ describe('connections:', function() {
       const m1 = db.model('testMod', schema);
       const m2 = db2.model('testMod', schema);
 
-      m1.create({body: 'this is some text', thing: 1}, function(err, i1) {
+      m1.create({ body: 'this is some text', thing: 1 }, function(err, i1) {
         assert.ifError(err);
-        m2.create({body: 'this is another body', thing: 2}, function(err, i2) {
+        m2.create({ body: 'this is another body', thing: 2 }, function(err, i2) {
           assert.ifError(err);
 
           m1.findById(i1.id, function(err, item1) {
@@ -1090,7 +1090,7 @@ describe('connections:', function() {
         it('should return false', function(done) {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {
             user: 'user',
-            auth: {authMechanism: 'MONGODB-X509'}
+            auth: { authMechanism: 'MONGODB-X509' }
           });
           db.catch(() => {});
           assert.equal(db.shouldAuthenticate(), true);
@@ -1104,7 +1104,7 @@ describe('connections:', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {
             user: 'user',
             pass: 'pass',
-            auth: {authMechanism: 'MONGODB-X509'}
+            auth: { authMechanism: 'MONGODB-X509' }
           });
           db.catch(() => {});
 
diff --git a/test/document.isselected.test.js b/test/document.isselected.test.js
index 4cea9e4b10f..ef199240a6a 100644
--- a/test/document.isselected.test.js
+++ b/test/document.isselected.test.js
@@ -37,7 +37,7 @@ for (const i in EventEmitter.prototype) {
  * Set a dummy schema to simulate compilation.
  */
 
-const em = new Schema({title: String, body: String});
+const em = new Schema({ title: String, body: String });
 em.virtual('works').get(function() {
   return 'em virtual works';
 });
@@ -48,7 +48,7 @@ const schema = new Schema({
   nested: {
     age: Number,
     cool: ObjectId,
-    deep: {x: String},
+    deep: { x: String },
     path: String,
     setr: String
   },
@@ -107,10 +107,10 @@ describe('document', function() {
         age: 5,
         cool: DocumentObjectId.createFromHexString('4c6c2d6240ced95d0e00003c'),
         path: 'my path',
-        deep: {x: 'a string'}
+        deep: { x: 'a string' }
       },
       notapath: 'i am not in the schema',
-      em: [{title: 'gocars'}]
+      em: [{ title: 'gocars' }]
     });
 
     assert.ok(doc.isSelected('_id'));
@@ -146,7 +146,7 @@ describe('document', function() {
       test: 'test',
       numbers: [4, 5, 6, 7],
       nested: {
-        deep: {x: 'a string'}
+        deep: { x: 'a string' }
       }
     });
 
@@ -177,7 +177,7 @@ describe('document', function() {
     doc = new TestDocument(undefined, selection);
 
     doc.init({
-      em: [{title: 'one'}]
+      em: [{ title: 'one' }]
     });
 
     assert.ok(doc.isSelected('_id'));
@@ -212,7 +212,7 @@ describe('document', function() {
         age: 5,
         cool: DocumentObjectId.createFromHexString('4c6c2d6240ced95d0e00003c'),
         path: 'my path',
-        deep: {x: 'a string'}
+        deep: { x: 'a string' }
       },
       notapath: 'i am not in the schema'
     });
@@ -249,7 +249,7 @@ describe('document', function() {
         age: 5,
         cool: DocumentObjectId.createFromHexString('4c6c2d6240ced95d0e00003c'),
         path: 'my path',
-        deep: {x: 'a string'}
+        deep: { x: 'a string' }
       },
       notapath: 'i am not in the schema'
     });
@@ -257,7 +257,7 @@ describe('document', function() {
     assert.ok(!doc.isSelected('_id'));
     assert.ok(doc.isSelected('nested.deep.x.no'));
 
-    doc = new TestDocument({test: 'boom'});
+    doc = new TestDocument({ test: 'boom' });
     assert.ok(doc.isSelected('_id'));
     assert.ok(doc.isSelected('test'));
     assert.ok(doc.isSelected('numbers'));
@@ -283,12 +283,12 @@ describe('document', function() {
     };
 
     doc = new TestDocument(undefined, selection);
-    doc.init({_id: 'test'});
+    doc.init({ _id: 'test' });
 
     assert.ok(doc.isSelected('_id'));
     assert.ok(!doc.isSelected('test'));
 
-    doc = new TestDocument({test: 'boom'}, true);
+    doc = new TestDocument({ test: 'boom' }, true);
     assert.ok(doc.isSelected('_id'));
     assert.ok(doc.isSelected('test'));
     assert.ok(doc.isSelected('numbers'));
@@ -322,7 +322,7 @@ describe('document', function() {
         age: 5,
         cool: DocumentObjectId.createFromHexString('4c6c2d6240ced95d0e00003c'),
         path: 'my path',
-        deep: {x: 'a string'}
+        deep: { x: 'a string' }
       },
       notapath: 'i am not in the schema'
     });
@@ -350,7 +350,7 @@ describe('document', function() {
       test: 'test',
       numbers: [4, 5, 6, 7],
       nested: {
-        deep: {x: 'a string'}
+        deep: { x: 'a string' }
       }
     });
 
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 590c42ad13f..049ff975c38 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -41,7 +41,7 @@ const BlogPost = new Schema({
   numbers: [Number],
   owners: [ObjectId],
   comments: [Comments],
-  nested: {array: [Number]}
+  nested: { array: [Number] }
 });
 
 BlogPost
@@ -113,8 +113,8 @@ describe('document modified', function() {
 
     it('of embedded docs reset after save', function(done) {
       const BlogPost = db.model(modelName, collection);
-      const post = new BlogPost({title: 'hocus pocus'});
-      post.comments.push({title: 'Humpty Dumpty', comments: [{title: 'nested'}]});
+      const post = new BlogPost({ title: 'hocus pocus' });
+      post.comments.push({ title: 'Humpty Dumpty', comments: [{ title: 'nested' }] });
       post.save(function(err) {
         assert.strictEqual(null, err);
         const mFlag = post.comments[0].isModified('title');
@@ -128,7 +128,7 @@ describe('document modified', function() {
   describe('isDefault', function() {
     it('works', function(done) {
       const MyModel = db.model('test',
-        {name: {type: String, default: 'Val '}});
+        { name: { type: String, default: 'Val ' } });
       const m = new MyModel();
       assert.ok(m.$isDefault('name'));
       done();
@@ -195,7 +195,7 @@ describe('document modified', function() {
         post.init({
           title: 'Test',
           slug: 'test',
-          comments: [{title: 'Test', date: new Date, body: 'Test'}]
+          comments: [{ title: 'Test', date: new Date, body: 'Test' }]
         });
 
         assert.equal(post.isModified('comments.0.title'), false);
@@ -213,7 +213,7 @@ describe('document modified', function() {
         post.init({
           title: 'Test',
           slug: 'test',
-          comments: [{title: 'Test', date: new Date, body: 'Test'}]
+          comments: [{ title: 'Test', date: new Date, body: 'Test' }]
         });
 
         assert.equal(post.isModified('comments.0.body'), false);
@@ -258,12 +258,12 @@ describe('document modified', function() {
           visitors: 5
         },
         published: true,
-        mixed: {x: [{y: [1, 'yes', 2]}]},
+        mixed: { x: [{ y: [1, 'yes', 2] }] },
         numbers: [],
         owners: [new DocumentObjectId, new DocumentObjectId],
         comments: [
-          {title: 'Test', date: new Date, body: 'Test'},
-          {title: 'Super', date: new Date, body: 'Cool'}
+          { title: 'Test', date: new Date, body: 'Test' },
+          { title: 'Super', date: new Date, body: 'Cool' }
         ]
       };
 
@@ -288,7 +288,7 @@ describe('document modified', function() {
           assert.equal(postRead.isModified('owners'), false);
           assert.equal(postRead.isModified('comments'), false);
           const arr = postRead.comments.slice();
-          arr[2] = postRead.comments.create({title: 'index'});
+          arr[2] = postRead.comments.create({ title: 'index' });
           postRead.comments = arr;
           assert.equal(postRead.isModified('comments'), true);
           done();
@@ -298,7 +298,7 @@ describe('document modified', function() {
 
     it('should let you set ref paths (gh-1530)', function(done) {
       const parentSchema = new Schema({
-        child: {type: Schema.Types.ObjectId, ref: 'gh-1530-2'}
+        child: { type: Schema.Types.ObjectId, ref: 'gh-1530-2' }
       });
       const Parent = db.model('gh-1530-1', parentSchema);
       const childSchema = new Schema({
@@ -333,12 +333,12 @@ describe('document modified', function() {
           assert.ok(typeof p.child.name === 'undefined');
           assert.equal(preCalls, 0);
           assert.equal(postCalls, 0);
-          Child.findOne({name: 'Luke'}, function(error, child) {
+          Child.findOne({ name: 'Luke' }, function(error, child) {
             assert.ifError(error);
             assert.ok(!child);
             originalParent.child.save(function(error) {
               assert.ifError(error);
-              Child.findOne({name: 'Luke'}, function(error, child) {
+              Child.findOne({ name: 'Luke' }, function(error, child) {
                 assert.ifError(error);
                 assert.ok(child);
                 assert.equal(p.child.toString(), child._id.toString());
@@ -353,14 +353,14 @@ describe('document modified', function() {
     it('properly sets populated for gh-1530 (gh-2678)', function(done) {
       const parentSchema = new Schema({
         name: String,
-        child: {type: Schema.Types.ObjectId, ref: 'Child'}
+        child: { type: Schema.Types.ObjectId, ref: 'Child' }
       });
 
       const Parent = db.model('Parent', parentSchema, 'parents');
       const Child = db.model('Child', parentSchema, 'children');
 
-      const child = new Child({name: 'Mary'});
-      const p = new Parent({name: 'Alex', child: child});
+      const child = new Child({ name: 'Mary' });
+      const p = new Parent({ name: 'Alex', child: child });
 
       assert.equal(child._id.toString(), p.populated('child').toString());
       done();
@@ -380,14 +380,14 @@ describe('document modified', function() {
       it('gh-1530 for arrays (gh-3575)', function(done) {
         const parentSchema = new Schema({
           name: String,
-          children: [{type: Schema.Types.ObjectId, ref: 'Child'}]
+          children: [{ type: Schema.Types.ObjectId, ref: 'Child' }]
         });
 
         const Parent = db.model('Parent', parentSchema, 'parents');
         const Child = db.model('Child', parentSchema, 'children');
 
-        const child = new Child({name: 'Luke'});
-        const p = new Parent({name: 'Anakin', children: [child]});
+        const child = new Child({ name: 'Luke' });
+        const p = new Parent({ name: 'Anakin', children: [child] });
 
         assert.equal('Luke', p.children[0].name);
         assert.ok(p.populated('children'));
@@ -396,23 +396,23 @@ describe('document modified', function() {
 
       it('setting nested arrays (gh-3721)', function(done) {
         const userSchema = new Schema({
-          name: {type: Schema.Types.String}
+          name: { type: Schema.Types.String }
         });
         const User = db.model('User', userSchema);
 
         const accountSchema = new Schema({
           roles: [{
-            name: {type: Schema.Types.String},
-            users: [{type: Schema.Types.ObjectId, ref: 'User'}]
+            name: { type: Schema.Types.String },
+            users: [{ type: Schema.Types.ObjectId, ref: 'User' }]
           }]
         });
 
         const Account = db.model('Account', accountSchema);
 
-        const user = new User({name: 'Test'});
+        const user = new User({ name: 'Test' });
         const account = new Account({
           roles: [
-            {name: 'test group', users: [user]}
+            { name: 'test group', users: [user] }
           ]
         });
 
@@ -421,13 +421,13 @@ describe('document modified', function() {
       });
 
       it('with discriminators (gh-3575)', function(done) {
-        const shapeSchema = new mongoose.Schema({}, {discriminatorKey: 'kind'});
+        const shapeSchema = new mongoose.Schema({}, { discriminatorKey: 'kind' });
 
         const Shape = mongoose.model('gh3575', shapeSchema);
 
         const Circle = Shape.discriminator('gh3575_0', new mongoose.Schema({
           radius: { type: Number }
-        }, {discriminatorKey: 'kind'}));
+        }, { discriminatorKey: 'kind' }));
 
         const fooSchema = new mongoose.Schema({
           bars: [{
@@ -450,18 +450,18 @@ describe('document modified', function() {
 
       it('updates embedded doc parents upon direct assignment (gh-5189)', function(done) {
         const familySchema = new Schema({
-          children: [{name: {type: String, required: true}}]
+          children: [{ name: { type: String, required: true } }]
         });
         const Family = db.model('Family', familySchema);
         Family.create({
           children: [
-            {name: 'John'},
-            {name: 'Mary'}
+            { name: 'John' },
+            { name: 'Mary' }
           ]
         }, function(err, family) {
-          family.set({children: family.children.slice(1)});
+          family.set({ children: family.children.slice(1) });
           family.children.forEach(function(child) {
-            child.set({name: 'Maryanne'});
+            child.set({ name: 'Maryanne' });
           });
 
           assert.equal(family.validateSync(), undefined);
@@ -471,9 +471,9 @@ describe('document modified', function() {
     });
 
     it('should support setting mixed paths by string (gh-1418)', function(done) {
-      const BlogPost = db.model('1418', new Schema({mixed: {}}));
+      const BlogPost = db.model('1418', new Schema({ mixed: {} }));
       let b = new BlogPost;
-      b.init({mixed: {}});
+      b.init({ mixed: {} });
 
       let path = 'mixed.path';
       assert.ok(!b.isModified(path));
@@ -483,13 +483,13 @@ describe('document modified', function() {
       assert.equal(b.get(path), 3);
 
       b = new BlogPost;
-      b.init({mixed: {}});
+      b.init({ mixed: {} });
       path = 'mixed.9a';
       b.set(path, 4);
       assert.ok(b.isModified(path));
       assert.equal(b.get(path), 4);
 
-      b = new BlogPost({mixed: {}});
+      b = new BlogPost({ mixed: {} });
       b.save(function(err) {
         assert.ifError(err);
 
@@ -526,7 +526,7 @@ describe('document modified', function() {
 
       const Parent = db.model('gh-1754', parentSchema);
       Parent.create(
-        {child: [{name: 'Brian', grandChild: [{name: 'Jake'}]}]},
+        { child: [{ name: 'Brian', grandChild: [{ name: 'Jake' }] }] },
         function(error, p) {
           assert.ifError(error);
           assert.ok(p);
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index 0bbb2d2dd2a..e8957e921c2 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -39,7 +39,7 @@ TestDocument.prototype.__proto__ = Document.prototype;
  * Set a dummy schema to simulate compilation.
  */
 
-const em = new Schema({title: String, body: String});
+const em = new Schema({ title: String, body: String });
 em.virtual('works').get(function() {
   return 'em virtual works';
 });
@@ -50,7 +50,7 @@ const schema = new Schema({
   nested: {
     age: Number,
     cool: ObjectId,
-    deep: {x: String},
+    deep: { x: String },
     path: String,
     setr: String
   },
@@ -74,18 +74,18 @@ TestDocument.prototype.$__setSchema(schema);
 const User = new Schema({
   name: String,
   email: String,
-  gender: {type: String, enum: ['male', 'female'], default: 'male'},
-  age: {type: Number, default: 21},
-  blogposts: [{type: ObjectId, ref: 'doc.populate.b'}]
-}, {collection: 'doc.populate.us'});
+  gender: { type: String, enum: ['male', 'female'], default: 'male' },
+  age: { type: Number, default: 21 },
+  blogposts: [{ type: ObjectId, ref: 'doc.populate.b' }]
+}, { collection: 'doc.populate.us' });
 
 /**
  * Comment subdocument schema.
  */
 
 const Comment = new Schema({
-  asers: [{type: ObjectId, ref: 'doc.populate.u'}],
-  _creator: {type: ObjectId, ref: 'doc.populate.u'},
+  asers: [{ type: ObjectId, ref: 'doc.populate.u' }],
+  _creator: { type: ObjectId, ref: 'doc.populate.u' },
   content: String
 });
 
@@ -94,10 +94,10 @@ const Comment = new Schema({
  */
 
 const BlogPost = new Schema({
-  _creator: {type: ObjectId, ref: 'doc.populate.u'},
+  _creator: { type: ObjectId, ref: 'doc.populate.u' },
   title: String,
   comments: [Comment],
-  fans: [{type: ObjectId, ref: 'doc.populate.u'}]
+  fans: [{ type: ObjectId, ref: 'doc.populate.u' }]
 });
 
 mongoose.model('doc.populate.b', BlogPost);
@@ -133,7 +133,7 @@ describe('document.populate', function() {
         title: 'the how and why',
         _creator: user1,
         fans: [user1, user2],
-        comments: [{_creator: user2, content: 'user2'}, {_creator: user1, content: 'user1'}]
+        comments: [{ _creator: user2, content: 'user2' }, { _creator: user1, content: 'user1' }]
       }, function(err, p) {
         assert.ifError(err);
         post = p;
@@ -161,7 +161,7 @@ describe('document.populate', function() {
           assert.equal(Object.keys(post.$__.populate).length, 2);
           assert.ok('_creator' in post.$__.populate);
           assert.ok('fans' in post.$__.populate);
-          post.populate({path: '_creator'});
+          post.populate({ path: '_creator' });
           assert.equal(Object.keys(post.$__.populate).length, 2);
           assert.ok('_creator' in post.$__.populate);
           assert.ok('fans' in post.$__.populate);
@@ -174,7 +174,7 @@ describe('document.populate', function() {
           post.populate('_creator');
           assert.equal(Object.keys(post.$__.populate).length, 1);
           assert.equal(post.$__.populate._creator.select, undefined);
-          post.populate({path: '_creator', select: 'name'});
+          post.populate({ path: '_creator', select: 'name' });
           assert.equal(Object.keys(post.$__.populate).length, 1);
           assert.ok('_creator' in post.$__.populate);
           assert.equal(post.$__.populate._creator.select, 'name');
@@ -241,7 +241,7 @@ describe('document.populate', function() {
     B.findById(post, function(err, post) {
       const param = {};
       param.select = '-email';
-      param.options = {sort: 'name'};
+      param.options = { sort: 'name' };
       param.path = '_creator fans'; // 2 paths
 
       const creator_id = post._creator;
@@ -268,7 +268,7 @@ describe('document.populate', function() {
 
       const param = {};
       param.select = '-email';
-      param.options = {sort: 'name'};
+      param.options = { sort: 'name' };
       param.path = '_creator';
       post.populate(param);
       param.path = 'fans';
@@ -292,7 +292,7 @@ describe('document.populate', function() {
     B.findById(post, function(err, post) {
       const param = {};
       param.select = '-email';
-      param.options = {sort: 'name'};
+      param.options = { sort: 'name' };
       param.path = '_creator fans';
       param.model = 'doc.populate.u2';
 
@@ -323,7 +323,7 @@ describe('document.populate', function() {
         post.$__setValue('idontexist', user1._id);
 
         // populate the non-schema value by passing an explicit model
-        post.populate({path: 'idontexist', model: 'doc.populate.u'}, function(err, post) {
+        post.populate({ path: 'idontexist', model: 'doc.populate.u' }, function(err, post) {
           assert.ifError(err);
           assert.ok(post);
           assert.equal(user1._id.toString(), post.get('idontexist')._id);
@@ -371,19 +371,19 @@ describe('document.populate', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: String, ref: 'UserWithStringId'},
+      author: { type: String, ref: 'UserWithStringId' },
       body: String
     });
 
     const User = db.model('UserWithStringId', UserSchema, random());
     const Note = db.model('NoteWithStringId', NoteSchema, random());
 
-    const alice = new User({_id: 'alice', name: 'Alice In Wonderland'});
+    const alice = new User({ _id: 'alice', name: 'Alice In Wonderland' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 'alice', body: 'Buy Milk'});
+      const note = new Note({ author: 'alice', body: 'Buy Milk' });
       note.populate('author', function(err) {
         assert.ifError(err);
         assert.ok(note.author);
@@ -401,19 +401,19 @@ describe('document.populate', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Buffer, ref: 'UserWithBufferId'},
+      author: { type: Buffer, ref: 'UserWithBufferId' },
       body: String
     });
 
     const User = db.model('UserWithBufferId', UserSchema, random());
     const Note = db.model('NoteWithBufferId', NoteSchema, random());
 
-    const alice = new User({_id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice'});
+    const alice = new User({ _id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 'alice', body: 'Buy Milk'});
+      const note = new Note({ author: 'alice', body: 'Buy Milk' });
       note.save(function(err) {
         assert.ifError(err);
 
@@ -439,19 +439,19 @@ describe('document.populate', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Number, ref: 'UserWithNumberId'},
+      author: { type: Number, ref: 'UserWithNumberId' },
       body: String
     });
 
     const User = db.model('UserWithNumberId', UserSchema, random());
     const Note = db.model('NoteWithNumberId', NoteSchema, random());
 
-    const alice = new User({_id: 2359, name: 'Alice'});
+    const alice = new User({ _id: 2359, name: 'Alice' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 2359, body: 'Buy Milk'});
+      const note = new Note({ author: 2359, body: 'Buy Milk' });
       note.populate('author').populate(function(err, note) {
         assert.ifError(err);
         assert.ok(note.author);
@@ -481,13 +481,13 @@ describe('document.populate', function() {
 
   describe('of new document', function() {
     it('should save just the populated _id (gh-1442)', function() {
-      const b = new B({_creator: user1});
+      const b = new B({ _creator: user1 });
       return co(function*() {
         yield b.populate('_creator').execPopulate();
         assert.equal(b._creator.name, 'Phoenix');
         yield b.save();
 
-        const _b = yield B.collection.findOne({_id: b._id});
+        const _b = yield B.collection.findOne({ _id: b._id });
         assert.equal(_b._creator.toString(), String(user1._id));
       });
     });
@@ -499,17 +499,17 @@ describe('document.populate', function() {
     });
 
     const Band = db.model('gh3308_0', {
-      guitarist: {type: Schema.Types.ObjectId, ref: 'gh3308'}
+      guitarist: { type: Schema.Types.ObjectId, ref: 'gh3308' }
     });
 
-    const slash = new Person({name: 'Slash'});
-    const gnr = new Band({guitarist: slash._id});
+    const slash = new Person({ name: 'Slash' });
+    const gnr = new Band({ guitarist: slash._id });
 
     gnr.guitarist = slash;
     assert.equal(gnr.guitarist.name, 'Slash');
     assert.ok(gnr.populated('guitarist'));
 
-    const buckethead = new Person({name: 'Buckethead'});
+    const buckethead = new Person({ name: 'Buckethead' });
     gnr.guitarist = buckethead._id;
     assert.ok(!gnr.populated('guitarist'));
 
@@ -650,11 +650,11 @@ describe('document.populate', function() {
 
       const Band = db.model('gh6073_2', {
         name: String,
-        members: [{type: Schema.Types.ObjectId, ref: 'gh6073_1'}],
-        lead: {type: Schema.Types.ObjectId, ref: 'gh6073_1'}
+        members: [{ type: Schema.Types.ObjectId, ref: 'gh6073_1' }],
+        lead: { type: Schema.Types.ObjectId, ref: 'gh6073_1' }
       });
 
-      const people = [{name: 'Axl Rose'}, {name: 'Slash'}];
+      const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
       Person.create(people, function(error, docs) {
         assert.ifError(error);
         const band = {
@@ -817,7 +817,7 @@ describe('document.populate', function() {
   });
 
   it('handles pulling from populated array (gh-3579)', function(done) {
-    const barSchema = new Schema({name: String});
+    const barSchema = new Schema({ name: String });
 
     const Bar = db.model('gh3579', barSchema);
 
@@ -830,9 +830,9 @@ describe('document.populate', function() {
 
     const Foo = db.model('gh3579_0', fooSchema);
 
-    Bar.create([{name: 'bar1'}, {name: 'bar2'}], function(error, docs) {
+    Bar.create([{ name: 'bar1' }, { name: 'bar2' }], function(error, docs) {
       assert.ifError(error);
-      const foo = new Foo({bars: [docs[0], docs[1]]});
+      const foo = new Foo({ bars: [docs[0], docs[1]] });
       foo.bars.pull(docs[0]._id);
       foo.save(function(error) {
         assert.ifError(error);
@@ -870,8 +870,8 @@ describe('document.populate', function() {
       const Player = db.model('gh7440_Player_0', playerSchema);
 
       return co(function*() {
-        const player = yield Player.create({name: 'Derek Jeter', _id: 'test1' });
-        yield Team.create({name: 'Yankees', captain: 'test1'});
+        const player = yield Player.create({ name: 'Derek Jeter', _id: 'test1' });
+        yield Team.create({ name: 'Yankees', captain: 'test1' });
 
         yield player.populate('teams').execPopulate();
         assert.deepEqual(player.populated('teams'), ['test1']);
@@ -892,8 +892,8 @@ describe('document.populate', function() {
       const Player = db.model('gh7440_Player_1', playerSchema);
 
       return co(function*() {
-        const player = yield Player.create({name: 'Derek Jeter', _id: 'test1' });
-        yield Team.create({name: 'Yankees', captain: 'test1'});
+        const player = yield Player.create({ name: 'Derek Jeter', _id: 'test1' });
+        yield Team.create({ name: 'Yankees', captain: 'test1' });
 
         yield player.populate('team').execPopulate();
         assert.deepEqual(player.populated('team'), 'test1');
@@ -983,11 +983,11 @@ describe('document.populate', function() {
     const O = db.model('gh7685_3', schema3);
 
     return co(function*() {
-      const m = yield M.create({a: 'TEST'});
-      const n = yield N.create({g: m._id});
-      const o = yield O.create({i: n._id});
+      const m = yield M.create({ a: 'TEST' });
+      const n = yield N.create({ g: m._id });
+      const o = yield O.create({ i: n._id });
 
-      const doc = yield O.findOne({_id: o._id}).populate('i').exec();
+      const doc = yield O.findOne({ _id: o._id }).populate('i').exec();
       const finalDoc = yield doc.populate('i.g').execPopulate();
 
       assert.ok(finalDoc.populated('i.g'));
diff --git a/test/document.strict.test.js b/test/document.strict.test.js
index 15a6b530c31..31c41ce2e8c 100644
--- a/test/document.strict.test.js
+++ b/test/document.strict.test.js
@@ -29,14 +29,14 @@ describe('document: strict mode:', function() {
 
     before(function() {
       const raw = {
-        ts: {type: Date, default: Date.now},
+        ts: { type: Date, default: Date.now },
         content: String,
         mixed: {},
-        deepMixed: {'4a': {}},
+        deepMixed: { '4a': {} },
         arrayMixed: []
       };
 
-      const lax = new Schema(raw, {strict: false, minimize: false});
+      const lax = new Schema(raw, { strict: false, minimize: false });
       const strict = new Schema(raw);
 
       Lax = db.model('Lax', lax);
@@ -75,7 +75,7 @@ describe('document: strict mode:', function() {
     });
 
     it('when creating models with strict schemas', function(done) {
-      const s = new Strict({content: 'sample', rouge: 'data'});
+      const s = new Strict({ content: 'sample', rouge: 'data' });
       assert.equal(s.$__.strictMode, true);
 
       const so = s.toObject();
@@ -92,7 +92,7 @@ describe('document: strict mode:', function() {
 
     it('when overriding strictness', function(done) {
       // instance override
-      let instance = new Lax({content: 'sample', rouge: 'data'}, true);
+      let instance = new Lax({ content: 'sample', rouge: 'data' }, true);
       assert.ok(instance.$__.strictMode);
 
       instance = instance.toObject();
@@ -101,7 +101,7 @@ describe('document: strict mode:', function() {
       assert.ok('ts' in instance);
 
       // hydrate works as normal, but supports the schema level flag.
-      let s2 = new Strict({content: 'sample', rouge: 'data'}, false);
+      let s2 = new Strict({ content: 'sample', rouge: 'data' }, false);
       assert.equal(s2.$__.strictMode, false);
       s2 = s2.toObject();
       assert.ok('ts' in s2);
@@ -110,7 +110,7 @@ describe('document: strict mode:', function() {
 
       // testing init
       const s3 = new Strict();
-      s3.init({content: 'sample', rouge: 'data'});
+      s3.init({ content: 'sample', rouge: 'data' });
       s3.toObject();
       assert.equal(s3.content, 'sample');
       assert.ok(!('rouge' in s3));
@@ -120,7 +120,7 @@ describe('document: strict mode:', function() {
 
     it('when using Model#create', function(done) {
       // strict on create
-      Strict.create({content: 'sample2', rouge: 'data'}, function(err, doc) {
+      Strict.create({ content: 'sample2', rouge: 'data' }, function(err, doc) {
         assert.equal(doc.content, 'sample2');
         assert.ok(!('rouge' in doc));
         assert.ok(!doc.rouge);
@@ -135,31 +135,31 @@ describe('document: strict mode:', function() {
 
   it('nested doc', function(done) {
     const lax = new Schema({
-      name: {last: String}
-    }, {strict: false});
+      name: { last: String }
+    }, { strict: false });
 
     const strict = new Schema({
-      name: {last: String}
+      name: { last: String }
     });
 
     const Lax = db.model('NestedLax', lax, 'nestdoc' + random());
     const Strict = db.model('NestedStrict', strict, 'nestdoc' + random());
 
     let l = new Lax;
-    l.set('name', {last: 'goose', hack: 'xx'});
+    l.set('name', { last: 'goose', hack: 'xx' });
     l = l.toObject();
     assert.equal(l.name.last, 'goose');
     assert.equal(l.name.hack, 'xx');
 
     let s = new Strict;
-    s.set({name: {last: 'goose', hack: 'xx'}});
+    s.set({ name: { last: 'goose', hack: 'xx' } });
     s = s.toObject();
     assert.equal(s.name.last, 'goose');
     assert.ok(!('hack' in s.name));
     assert.ok(!s.name.hack);
 
     s = new Strict;
-    s.set('name', {last: 'goose', hack: 'xx'});
+    s.set('name', { last: 'goose', hack: 'xx' });
     s.set('shouldnt.exist', ':(');
     s = s.toObject();
     assert.equal(s.name.last, 'goose');
@@ -171,26 +171,26 @@ describe('document: strict mode:', function() {
 
   it('sub doc', function(done) {
     const lax = new Schema({
-      ts: {type: Date, default: Date.now},
+      ts: { type: Date, default: Date.now },
       content: String
-    }, {strict: false});
+    }, { strict: false });
 
     const strict = new Schema({
-      ts: {type: Date, default: Date.now},
+      ts: { type: Date, default: Date.now },
       content: String
     });
 
-    const Lax = db.model('EmbeddedLax', new Schema({dox: [lax]}, {strict: false}), 'embdoc' + random());
-    const Strict = db.model('EmbeddedStrict', new Schema({dox: [strict]}, {strict: false}), 'embdoc' + random());
+    const Lax = db.model('EmbeddedLax', new Schema({ dox: [lax] }, { strict: false }), 'embdoc' + random());
+    const Strict = db.model('EmbeddedStrict', new Schema({ dox: [strict] }, { strict: false }), 'embdoc' + random());
 
-    let l = new Lax({dox: [{content: 'sample', rouge: 'data'}]});
+    let l = new Lax({ dox: [{ content: 'sample', rouge: 'data' }] });
     assert.equal(l.dox[0].$__.strictMode, false);
     l = l.dox[0].toObject();
     assert.equal(l.content, 'sample');
     assert.equal(l.rouge, 'data');
     assert.ok(l.rouge);
 
-    let s = new Strict({dox: [{content: 'sample', rouge: 'data'}]});
+    let s = new Strict({ dox: [{ content: 'sample', rouge: 'data' }] });
     assert.equal(s.dox[0].$__.strictMode, true);
     s = s.dox[0].toObject();
     assert.ok('ts' in s);
@@ -200,14 +200,14 @@ describe('document: strict mode:', function() {
 
     // testing init
     const s3 = new Strict();
-    s3.init({dox: [{content: 'sample', rouge: 'data'}]});
+    s3.init({ dox: [{ content: 'sample', rouge: 'data' }] });
     s3.toObject();
     assert.equal(s3.dox[0].content, 'sample');
     assert.ok(!('rouge' in s3.dox[0]));
     assert.ok(!s3.dox[0].rouge);
 
     // strict on create
-    Strict.create({dox: [{content: 'sample2', rouge: 'data'}]}, function(err, doc) {
+    Strict.create({ dox: [{ content: 'sample2', rouge: 'data' }] }, function(err, doc) {
       assert.equal(doc.dox[0].content, 'sample2');
       assert.ok(!('rouge' in doc.dox[0]));
       assert.ok(!doc.dox[0].rouge);
@@ -265,20 +265,20 @@ describe('document: strict mode:', function() {
     });
 
     const Strict = db.model('Strict', strict);
-    const s = new Strict({bool: true});
+    const s = new Strict({ bool: true });
 
     // insert non-schema property
     const doc = s.toObject();
     doc.notInSchema = true;
 
-    Strict.collection.insertOne(doc, {w: 1}, function(err) {
+    Strict.collection.insertOne(doc, { w: 1 }, function(err) {
       assert.ifError(err);
       Strict.findById(doc._id, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc._doc.bool, true);
         assert.equal(doc._doc.notInSchema, true);
         doc.bool = undefined;
-        doc.set('notInSchema', undefined, {strict: false});
+        doc.set('notInSchema', undefined, { strict: false });
         doc.save(function() {
           Strict.findById(doc._id, function(err, doc) {
             assert.ifError(err);
@@ -299,7 +299,7 @@ describe('document: strict mode:', function() {
     });
 
     const Strict = db.model('Strict', strict);
-    const s = new Strict({bool: true});
+    const s = new Strict({ bool: true });
 
     // insert non-schema property
     const doc = s.toObject();
@@ -313,7 +313,7 @@ describe('document: strict mode:', function() {
         assert.equal(doc._doc.bool, true);
         assert.equal(doc._doc.notInSchema, true);
 
-        Strict.updateOne({_id: doc._id}, {$unset: {bool: 1, notInSchema: 1}}, {strict: false},
+        Strict.updateOne({ _id: doc._id }, { $unset: { bool: 1, notInSchema: 1 } }, { strict: false },
           function(err) {
             assert.ifError(err);
 
@@ -337,13 +337,13 @@ describe('document: strict mode:', function() {
     });
 
     const Strict = db.model('Strict', strict);
-    const s = new Strict({bool: true});
+    const s = new Strict({ bool: true });
 
     // insert non-schema property
     const doc = s.toObject();
     doc.notInSchema = true;
 
-    Strict.collection.insertOne(doc, {w: 1}, function(err) {
+    Strict.collection.insertOne(doc, { w: 1 }, function(err) {
       assert.ifError(err);
 
       Strict.findById(doc._id, function(err, doc) {
@@ -351,7 +351,7 @@ describe('document: strict mode:', function() {
         assert.equal(doc._doc.bool, true);
         assert.equal(doc._doc.notInSchema, true);
 
-        Strict.findOneAndUpdate({_id: doc._id}, {$unset: {bool: 1, notInSchema: 1}}, {strict: false, w: 1},
+        Strict.findOneAndUpdate({ _id: doc._id }, { $unset: { bool: 1, notInSchema: 1 } }, { strict: false, w: 1 },
           function(err) {
             assert.ifError(err);
 
@@ -368,7 +368,7 @@ describe('document: strict mode:', function() {
 
   describe('"throws" mode', function() {
     it('throws on set() of unknown property', function(done) {
-      const schema = new Schema({n: String, docs: [{x: [{y: String}]}]});
+      const schema = new Schema({ n: String, docs: [{ x: [{ y: String }] }] });
       schema.set('strict', 'throw');
       const M = mongoose.model('throwStrictSet', schema, 'tss_' + random());
       const m = new M;
@@ -417,19 +417,19 @@ describe('document: strict mode:', function() {
     it('fails with extra fields', function(done) {
       // Simple schema with throws option
       const FooSchema = new mongoose.Schema({
-        name: {type: String}
-      }, {strict: 'throw'});
+        name: { type: String }
+      }, { strict: 'throw' });
 
       // Create the model
       const Foo = mongoose.model('Foo1234', FooSchema);
 
       assert.doesNotThrow(function() {
-        new Foo({name: 'bar'});
+        new Foo({ name: 'bar' });
       });
 
       assert.throws(function() {
         // The extra baz field should throw
-        new Foo({name: 'bar', baz: 'bam'});
+        new Foo({ name: 'bar', baz: 'bam' });
       }, /Field `baz` is not in schema/);
 
       done();
@@ -438,15 +438,15 @@ describe('document: strict mode:', function() {
     it('doesnt throw with refs (gh-2665)', function(done) {
       // Simple schema with throws option
       const FooSchema = new mongoose.Schema({
-        name: {type: mongoose.Schema.Types.ObjectId, ref: 'test', required: false, default: null},
-        father: {name: {full: String}}
-      }, {strict: 'throw'});
+        name: { type: mongoose.Schema.Types.ObjectId, ref: 'test', required: false, default: null },
+        father: { name: { full: String } }
+      }, { strict: 'throw' });
 
       // Create the model
       const Foo = mongoose.model('gh2665', FooSchema);
 
       assert.doesNotThrow(function() {
-        new Foo({name: mongoose.Types.ObjectId(), father: {name: {full: 'bacon'}}});
+        new Foo({ name: mongoose.Types.ObjectId(), father: { name: { full: 'bacon' } } });
       });
 
       done();
@@ -455,14 +455,14 @@ describe('document: strict mode:', function() {
     it('set nested to num throws ObjectExpectedError (gh-3735)', function(done) {
       const schema = new Schema({
         resolved: {
-          by: {type: String}
+          by: { type: String }
         }
-      }, {strict: 'throw'});
+      }, { strict: 'throw' });
 
       const Test = mongoose.model('gh3735', schema);
 
       assert.throws(function() {
-        new Test({resolved: 123});
+        new Test({ resolved: 123 });
       }, /ObjectExpectedError/);
       done();
     });
diff --git a/test/document.test.js b/test/document.test.js
index 57f953b95cc..f608013633f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -50,7 +50,7 @@ for (const i in EventEmitter.prototype) {
  * Set a dummy schema to simulate compilation.
  */
 
-const em = new Schema({title: String, body: String});
+const em = new Schema({ title: String, body: String });
 em.virtual('works').get(function() {
   return 'em virtual works';
 });
@@ -61,7 +61,7 @@ const schema = new Schema({
   nested: {
     age: Number,
     cool: ObjectId,
-    deep: {x: String},
+    deep: { x: String },
     path: String,
     setr: String
   },
@@ -111,7 +111,7 @@ TestDocument.prototype.hooksTest = function(fn) {
   fn(null, arguments);
 };
 
-const childSchema = new Schema({counter: Number});
+const childSchema = new Schema({ counter: Number });
 
 const parentSchema = new Schema({
   name: String,
@@ -222,7 +222,7 @@ describe('document', function() {
   describe('shortcut getters', function() {
     it('return undefined for properties with a null/undefined parent object (gh-1326)', function(done) {
       const doc = new TestDocument;
-      doc.init({nested: null});
+      doc.init({ nested: null });
       assert.strictEqual(undefined, doc.nested.age);
       done();
     });
@@ -257,7 +257,7 @@ describe('document', function() {
         nested: {
           age: 2,
           cool: DocumentObjectId.createFromHexString('4cf70857337498f95900001c'),
-          deep: {x: 'yay'}
+          deep: { x: 'yay' }
         }
       });
 
@@ -324,7 +324,7 @@ describe('document', function() {
     assert.equal(doc.nested.age, 2);
     assert.ok(doc.isModified('nested.age'));
 
-    doc.nested = {path: 'overwrite the entire nested object'};
+    doc.nested = { path: 'overwrite the entire nested object' };
     assert.equal(doc.nested.age, undefined);
     assert.equal(Object.keys(doc._doc.nested).length, 1);
     assert.equal(doc.nested.path, 'overwrite the entire nested object');
@@ -350,7 +350,7 @@ describe('document', function() {
     doc.init({
       test: 'test',
       oids: [],
-      em: [{title: 'asdf'}],
+      em: [{ title: 'asdf' }],
       nested: {
         age: 5,
         cool: DocumentObjectId.createFromHexString('4c6c2d6240ced95d0e00003c'),
@@ -360,7 +360,7 @@ describe('document', function() {
       date: new Date
     });
 
-    let clone = doc.toObject({getters: true, virtuals: false});
+    let clone = doc.toObject({ getters: true, virtuals: false });
 
     assert.equal(clone.test, 'test');
     assert.ok(clone.oids instanceof Array);
@@ -371,7 +371,7 @@ describe('document', function() {
     assert.equal(clone.em[0].works, undefined);
     assert.ok(clone.date instanceof Date);
 
-    clone = doc.toObject({virtuals: true});
+    clone = doc.toObject({ virtuals: true });
 
     assert.equal(clone.test, 'test');
     assert.ok(clone.oids instanceof Array);
@@ -381,7 +381,7 @@ describe('document', function() {
     assert.equal(clone.nested.agePlus2, 7);
     assert.equal(clone.em[0].works, 'em virtual works');
 
-    clone = doc.toObject({getters: true});
+    clone = doc.toObject({ getters: true });
 
     assert.equal(clone.test, 'test');
     assert.ok(clone.oids instanceof Array);
@@ -392,8 +392,8 @@ describe('document', function() {
     assert.equal(clone.em[0].works, 'em virtual works');
 
     // test toObject options
-    doc.schema.options.toObject = {virtuals: true};
-    clone = doc.toObject({transform: false, virtuals: true});
+    doc.schema.options.toObject = { virtuals: true };
+    clone = doc.toObject({ transform: false, virtuals: true });
     assert.equal(clone.test, 'test');
     assert.ok(clone.oids instanceof Array);
     assert.equal(clone.nested.age, 5);
@@ -405,18 +405,18 @@ describe('document', function() {
     delete doc.schema.options.toObject;
 
     // minimize
-    clone = doc.toObject({minimize: true});
+    clone = doc.toObject({ minimize: true });
     assert.equal(clone.nested2, undefined);
-    clone = doc.toObject({minimize: true, getters: true});
+    clone = doc.toObject({ minimize: true, getters: true });
     assert.equal(clone.nested2, undefined);
-    clone = doc.toObject({minimize: false});
+    clone = doc.toObject({ minimize: false });
     assert.equal(clone.nested2.constructor.name, 'Object');
     assert.equal(Object.keys(clone.nested2).length, 1);
     clone = doc.toObject('2');
     assert.equal(clone.nested2, undefined);
 
-    doc.schema.options.toObject = {minimize: false};
-    clone = doc.toObject({transform: false, minimize: false});
+    doc.schema.options.toObject = { minimize: false };
+    clone = doc.toObject({ transform: false, minimize: false });
     assert.equal(clone.nested2.constructor.name, 'Object');
     assert.equal(Object.keys(clone.nested2).length, 1);
     delete doc.schema.options.toObject;
@@ -452,21 +452,21 @@ describe('document', function() {
     assert.equal(clone.nested.age, 5);
 
     // transform with return value
-    const out = {myid: doc._id.toString()};
+    const out = { myid: doc._id.toString() };
     doc.schema.options.toObject.transform = function(doc, ret) {
       // ignore embedded docs
       if (typeof doc.ownerDocument === 'function') {
         return;
       }
 
-      return {myid: ret._id.toString()};
+      return { myid: ret._id.toString() };
     };
 
     clone = doc.toObject();
     assert.deepEqual(out, clone);
 
     // ignored transform with inline options
-    clone = doc.toObject({x: 1, transform: false});
+    clone = doc.toObject({ x: 1, transform: false });
     assert.ok(!('myid' in clone));
     assert.equal(clone.test, 'test');
     assert.ok(clone.oids instanceof Array);
@@ -476,7 +476,7 @@ describe('document', function() {
     assert.equal(clone.em[0].constructor.name, 'Object');
 
     // applied transform when inline transform is true
-    clone = doc.toObject({x: 1});
+    clone = doc.toObject({ x: 1 });
     assert.deepEqual(out, clone);
 
     // transform passed inline
@@ -505,7 +505,7 @@ describe('document', function() {
   it('toObject transform', function(done) {
     const schema = new Schema({
       name: String,
-      places: [{type: ObjectId, ref: 'Place'}]
+      places: [{ type: ObjectId, ref: 'Place' }]
     });
 
     const schemaPlaces = new Schema({
@@ -522,13 +522,13 @@ describe('document', function() {
     const Test = db.model('Test', schema);
     const Places = db.model('Place', schemaPlaces);
 
-    Places.create({identity: 'a'}, {identity: 'b'}, {identity: 'c'}, function(err, a, b, c) {
-      Test.create({name: 'chetverikov', places: [a, b, c]}, function(err) {
+    Places.create({ identity: 'a' }, { identity: 'b' }, { identity: 'c' }, function(err, a, b, c) {
+      Test.create({ name: 'chetverikov', places: [a, b, c] }, function(err) {
         assert.ifError(err);
         Test.findOne({}).populate('places').exec(function(err, docs) {
           assert.ifError(err);
 
-          docs.toObject({transform: true});
+          docs.toObject({ transform: true });
 
           done();
         });
@@ -564,15 +564,15 @@ describe('document', function() {
       height: Number,
       rows: Number,
       width: Number
-    }, {_id: false, id: false});
+    }, { _id: false, id: false });
     const questionSchema = Schema({
       type: String,
       age: Number,
       clip: {
         type: clipSchema
       }
-    }, {_id: false, id: false});
-    const keySchema = Schema({ql: [questionSchema]}, {_id: false, id: false});
+    }, { _id: false, id: false });
+    const keySchema = Schema({ ql: [questionSchema] }, { _id: false, id: false });
     const Model = db.model('gh8468-2', Schema({
       name: String,
       keys: [keySchema]
@@ -580,12 +580,12 @@ describe('document', function() {
     const doc = new Model({
       name: 'test',
       keys: [
-        {ql: [
-          { type: 'mc', clip: {width: 1} },
-          { type: 'mc', clip: {height: 1, rows: 1} },
-          { type: 'mc', clip: {height: 2, rows: 1} },
-          { type: 'mc', clip: {height: 3, rows: 1} }
-        ]}
+        { ql: [
+          { type: 'mc', clip: { width: 1 } },
+          { type: 'mc', clip: { height: 1, rows: 1 } },
+          { type: 'mc', clip: { height: 2, rows: 1 } },
+          { type: 'mc', clip: { height: 3, rows: 1 } }
+        ] }
       ]
     });
     return doc.save().then(() => {
@@ -593,7 +593,7 @@ describe('document', function() {
       // the validation was called for the "clip" document twice in the
       // same stack, causing a "can't validate() the same doc multiple times in
       // parallel" warning
-      doc.keys[0].ql[0].clip = {width: 4.3, rows: 3};
+      doc.keys[0].ql[0].clip = { width: 4.3, rows: 3 };
       doc.keys[0].ql[0].age = 42;
 
       return doc.save();
@@ -647,7 +647,7 @@ describe('document', function() {
     });
     const Test = db.model('Test', schema);
 
-    Test.create({name: 'chetverikov', iWillNotBeDelete: true, 'nested.iWillNotBeDeleteToo': true}, function(err) {
+    Test.create({ name: 'chetverikov', iWillNotBeDelete: true, 'nested.iWillNotBeDeleteToo': true }, function(err) {
       assert.ifError(err);
       Test.findOne({}, function(err, doc) {
         assert.ifError(err);
@@ -729,10 +729,10 @@ describe('document', function() {
       const topic = new Topic({
         title: 'Favorite Foods',
         email: 'a@b.co',
-        followers: [{name: 'Val', email: 'val@test.co'}]
+        followers: [{ name: 'Val', email: 'val@test.co' }]
       });
 
-      const output = topic.toObject({transform: true});
+      const output = topic.toObject({ transform: true });
       assert.equal(output.title, 'favorite foods');
       assert.equal(output.email, 'a@b.co');
       assert.equal(output.followers[0].name, 'Val');
@@ -751,10 +751,10 @@ describe('document', function() {
         return this.firstName + ' ' + this.lastName;
       });
 
-      userSchema.set('toObject', {virtuals: false});
+      userSchema.set('toObject', { virtuals: false });
 
       const postSchema = new Schema({
-        owner: {type: Schema.Types.ObjectId, ref: 'User'},
+        owner: { type: Schema.Types.ObjectId, ref: 'User' },
         content: String
       });
 
@@ -762,15 +762,15 @@ describe('document', function() {
         return this.content.toUpperCase();
       });
 
-      postSchema.set('toObject', {virtuals: true});
+      postSchema.set('toObject', { virtuals: true });
       const User = db.model('User', userSchema);
       const Post = db.model('Post', postSchema);
 
-      const user = new User({firstName: 'Joe', lastName: 'Smith', password: 'password'});
+      const user = new User({ firstName: 'Joe', lastName: 'Smith', password: 'password' });
 
       user.save(function(err, savedUser) {
         assert.ifError(err);
-        const post = new Post({owner: savedUser._id, content: 'lorem ipsum'});
+        const post = new Post({ owner: savedUser._id, content: 'lorem ipsum' });
         post.save(function(err, savedPost) {
           assert.ifError(err);
           Post.findById(savedPost._id).populate('owner').exec(function(err, newPost) {
@@ -791,7 +791,7 @@ describe('document', function() {
       doc.init({
         test: 'test',
         oids: [],
-        em: [{title: 'asdf'}],
+        em: [{ title: 'asdf' }],
         nested: {
           age: 5,
           cool: DocumentObjectId.createFromHexString('4c6c2d6240ced95d0e00003c'),
@@ -806,7 +806,7 @@ describe('document', function() {
         return {};
       };
 
-      doc.schema.options.toJSON = {virtuals: true};
+      doc.schema.options.toJSON = { virtuals: true };
       let clone = doc.toJSON();
       assert.equal(clone.test, 'test');
       assert.ok(clone.oids instanceof Array);
@@ -819,7 +819,7 @@ describe('document', function() {
       delete doc.schema.options.toJSON;
       delete path.casterConstructor.prototype.toJSON;
 
-      doc.schema.options.toJSON = {minimize: false};
+      doc.schema.options.toJSON = { minimize: false };
       clone = doc.toJSON();
       assert.equal(clone.nested2.constructor.name, 'Object');
       assert.equal(Object.keys(clone.nested2).length, 1);
@@ -864,21 +864,21 @@ describe('document', function() {
       assert.equal(clone.nested.age, 5);
 
       // transform with return value
-      const out = {myid: doc._id.toString()};
+      const out = { myid: doc._id.toString() };
       doc.schema.options.toJSON.transform = function(doc, ret) {
         // ignore embedded docs
         if (typeof doc.ownerDocument === 'function') {
           return;
         }
 
-        return {myid: ret._id.toString()};
+        return { myid: ret._id.toString() };
       };
 
       clone = doc.toJSON();
       assert.deepEqual(out, clone);
 
       // ignored transform with inline options
-      clone = doc.toJSON({x: 1, transform: false});
+      clone = doc.toJSON({ x: 1, transform: false });
       assert.ok(!('myid' in clone));
       assert.equal(clone.test, 'test');
       assert.ok(clone.oids instanceof Array);
@@ -888,7 +888,7 @@ describe('document', function() {
       assert.equal(clone.em[0].constructor.name, 'Object');
 
       // applied transform when inline transform is true
-      clone = doc.toJSON({x: 1});
+      clone = doc.toJSON({ x: 1 });
       assert.deepEqual(out, clone);
 
       // transform passed inline
@@ -915,7 +915,7 @@ describe('document', function() {
     });
 
     it('jsonifying an object', function(done) {
-      const doc = new TestDocument({test: 'woot'});
+      const doc = new TestDocument({ test: 'woot' });
       const oidString = doc._id.toString();
       // convert to json string
       const json = JSON.stringify(doc);
@@ -928,9 +928,9 @@ describe('document', function() {
     });
 
     it('jsonifying an object\'s populated items works (gh-1376)', function(done) {
-      const userSchema = new Schema({name: String});
+      const userSchema = new Schema({ name: String });
       // includes virtual path when 'toJSON'
-      userSchema.set('toJSON', {getters: true});
+      userSchema.set('toJSON', { getters: true });
       userSchema.virtual('hello').get(function() {
         return 'Hello, ' + this.name;
       });
@@ -938,15 +938,15 @@ describe('document', function() {
 
       const groupSchema = new Schema({
         name: String,
-        _users: [{type: Schema.ObjectId, ref: 'User'}]
+        _users: [{ type: Schema.ObjectId, ref: 'User' }]
       });
 
       const Group = db.model('Group', groupSchema);
 
-      User.create({name: 'Alice'}, {name: 'Bob'}, function(err, alice, bob) {
+      User.create({ name: 'Alice' }, { name: 'Bob' }, function(err, alice, bob) {
         assert.ifError(err);
 
-        Group.create({name: 'mongoose', _users: [alice, bob]}, function(err, group) {
+        Group.create({ name: 'mongoose', _users: [alice, bob] }, function(err, group) {
           Group.findById(group).populate('_users').exec(function(err, group) {
             assert.ifError(err);
             assert.ok(group.toJSON()._users[0].hello);
@@ -1070,15 +1070,15 @@ describe('document', function() {
   describe.skip('#update', function() {
     it('returns a Query', function(done) {
       const mg = new mongoose.Mongoose;
-      const M = mg.model('Test', {s: String});
+      const M = mg.model('Test', { s: String });
       const doc = new M;
       assert.ok(doc.update() instanceof Query);
       done();
     });
     it('calling update on document should relay to its model (gh-794)', function(done) {
-      const Docs = new Schema({text: String});
+      const Docs = new Schema({ text: String });
       const docs = db.model('Test', Docs);
-      const d = new docs({text: 'A doc'});
+      const d = new docs({ text: 'A doc' });
       let called = false;
       d.save(function() {
         const oldUpdate = docs.update;
@@ -1092,7 +1092,7 @@ describe('document', function() {
           docs.update = oldUpdate;
           oldUpdate.apply(docs, arguments);
         };
-        d.update({$set: {text: 'A changed doc'}}, function(err) {
+        d.update({ $set: { text: 'A changed doc' } }, function(err) {
           assert.ifError(err);
           assert.equal(called, true);
           done();
@@ -1106,7 +1106,7 @@ describe('document', function() {
     const obj = doc.toObject();
 
     delete obj._id;
-    assert.deepEqual(obj, {numbers: [], oids: [], em: []});
+    assert.deepEqual(obj, { numbers: [], oids: [], em: [] });
     done();
   });
 
@@ -1126,7 +1126,7 @@ describe('document', function() {
   });
 
   it('methods on embedded docs should work', function(done) {
-    const ESchema = new Schema({name: String});
+    const ESchema = new Schema({ name: String });
 
     ESchema.methods.test = function() {
       return this.name + ' butter';
@@ -1136,10 +1136,10 @@ describe('document', function() {
     };
 
     const E = db.model('Test', ESchema);
-    const PSchema = new Schema({embed: [ESchema]});
+    const PSchema = new Schema({ embed: [ESchema] });
     const P = db.model('Test2', PSchema);
 
-    let p = new P({embed: [{name: 'peanut'}]});
+    let p = new P({ embed: [{ name: 'peanut' }] });
     assert.equal(typeof p.embed[0].test, 'function');
     assert.equal(typeof E.ten, 'function');
     assert.equal(p.embed[0].test(), 'peanut butter');
@@ -1147,7 +1147,7 @@ describe('document', function() {
 
     // test push casting
     p = new P;
-    p.embed.push({name: 'apple'});
+    p.embed.push({ name: 'apple' });
     assert.equal(typeof p.embed[0].test, 'function');
     assert.equal(typeof E.ten, 'function');
     assert.equal(p.embed[0].test(), 'apple butter');
@@ -1156,7 +1156,7 @@ describe('document', function() {
 
   it('setting a positional path does not cast value to array', function(done) {
     const doc = new TestDocument;
-    doc.init({numbers: [1, 3]});
+    doc.init({ numbers: [1, 3] });
     assert.equal(doc.numbers[0], 1);
     assert.equal(doc.numbers[1], 3);
     doc.set('numbers.1', 2);
@@ -1176,22 +1176,22 @@ describe('document', function() {
 
     const schema = new Schema({
       title: String,
-      embed1: [new Schema({name: String})],
-      embed2: [new Schema({name: String})],
-      embed3: [new Schema({name: String})],
-      embed4: [new Schema({name: String})],
-      embed5: [new Schema({name: String})],
-      embed6: [new Schema({name: String})],
-      embed7: [new Schema({name: String})],
-      embed8: [new Schema({name: String})],
-      embed9: [new Schema({name: String})],
-      embed10: [new Schema({name: String})],
-      embed11: [new Schema({name: String})]
+      embed1: [new Schema({ name: String })],
+      embed2: [new Schema({ name: String })],
+      embed3: [new Schema({ name: String })],
+      embed4: [new Schema({ name: String })],
+      embed5: [new Schema({ name: String })],
+      embed6: [new Schema({ name: String })],
+      embed7: [new Schema({ name: String })],
+      embed8: [new Schema({ name: String })],
+      embed9: [new Schema({ name: String })],
+      embed10: [new Schema({ name: String })],
+      embed11: [new Schema({ name: String })]
     });
 
     const S = db.model('Test', schema);
 
-    new S({title: 'test'});
+    new S({ title: 'test' });
     assert.equal(traced, false);
     done();
   });
@@ -1199,11 +1199,11 @@ describe('document', function() {
   it('unselected required fields should pass validation', function(done) {
     const Tschema = new Schema({
       name: String,
-      req: {type: String, required: true}
+      req: { type: String, required: true }
     });
     const T = db.model('Test', Tschema);
 
-    const t = new T({name: 'teeee', req: 'i am required'});
+    const t = new T({ name: 'teeee', req: 'i am required' });
     t.save(function(err) {
       assert.ifError(err);
       T.findById(t).select('name').exec(function(err, t) {
@@ -1252,12 +1252,12 @@ describe('document', function() {
       }, 'BAM'];
 
       schema = new Schema({
-        prop: {type: String, required: true, validate: validate},
-        nick: {type: String, required: true}
+        prop: { type: String, required: true, validate: validate },
+        nick: { type: String, required: true }
       });
 
       const M = db.model('Test', schema, collection);
-      const m = new M({prop: 'gh891', nick: 'validation test'});
+      const m = new M({ prop: 'gh891', nick: 'validation test' });
       m.save(function(err) {
         assert.ifError(err);
         assert.equal(called, true);
@@ -1283,13 +1283,13 @@ describe('document', function() {
       }, 'BAM'];
 
       schema = new Schema({
-        prop: {type: String, required: true, validate: validate},
-        nick: {type: String, required: true}
+        prop: { type: String, required: true, validate: validate },
+        nick: { type: String, required: true }
       });
 
       const M = db.model('Test', schema);
-      const m = new M({prop: 'gh891', nick: 'validation test'});
-      const mBad = new M({prop: 'other'});
+      const m = new M({ prop: 'gh891', nick: 'validation test' });
+      const mBad = new M({ prop: 'other' });
 
       const promise = m.validate();
       promise.then(function() {
@@ -1308,10 +1308,10 @@ describe('document', function() {
     });
 
     it('doesnt have stale cast errors (gh-2766)', function(done) {
-      const testSchema = new Schema({name: String});
+      const testSchema = new Schema({ name: String });
       const M = db.model('Test', testSchema);
 
-      const m = new M({_id: 'this is not a valid _id'});
+      const m = new M({ _id: 'this is not a valid _id' });
       assert.ok(!m.$isValid('_id'));
       assert.ok(m.validateSync().errors['_id'].name, 'CastError');
 
@@ -1326,10 +1326,10 @@ describe('document', function() {
 
     it('cast errors persist across validate() calls (gh-2766)', function(done) {
       const db = start();
-      const testSchema = new Schema({name: String});
+      const testSchema = new Schema({ name: String });
       const M = db.model('Test', testSchema);
 
-      const m = new M({_id: 'this is not a valid _id'});
+      const m = new M({ _id: 'this is not a valid _id' });
       assert.ok(!m.$isValid('_id'));
       m.validate(function(error) {
         assert.ok(error);
@@ -1350,7 +1350,7 @@ describe('document', function() {
     it('returns a promise when there are no validators', function(done) {
       let schema = null;
 
-      schema = new Schema({_id: String});
+      schema = new Schema({ _id: String });
 
       const M = db.model('Test', schema);
       const m = new M();
@@ -1371,10 +1371,10 @@ describe('document', function() {
       it('with required', function(done) {
         const schema = new Schema({
           name: String,
-          arr: {type: [], required: true}
+          arr: { type: [], required: true }
         });
         const M = db.model('Test', schema);
-        const m = new M({name: 'gh1109-1', arr: null});
+        const m = new M({ name: 'gh1109-1', arr: null });
         m.save(function(err) {
           assert.ok(/Path `arr` is required/.test(err));
           m.arr = null;
@@ -1401,11 +1401,11 @@ describe('document', function() {
         const validate = [validator, 'BAM'];
 
         const schema = new Schema({
-          arr: {type: [], validate: validate}
+          arr: { type: [], validate: validate }
         });
 
         const M = db.model('Test', schema);
-        const m = new M({name: 'gh1109-2', arr: [1]});
+        const m = new M({ name: 'gh1109-2', arr: [1] });
         assert.equal(called, false);
         m.save(function(err) {
           assert.equal(String(err), 'ValidationError: arr: BAM');
@@ -1428,14 +1428,14 @@ describe('document', function() {
         const validate = [validator, 'BAM'];
 
         const schema = new Schema({
-          arr: {type: [], required: true, validate: validate}
+          arr: { type: [], required: true, validate: validate }
         });
 
         const M = db.model('Test', schema, collection);
-        const m = new M({name: 'gh1109-3', arr: null});
+        const m = new M({ name: 'gh1109-3', arr: null });
         m.save(function(err) {
           assert.equal(err.errors.arr.message, 'Path `arr` is required.');
-          m.arr = [{nice: true}];
+          m.arr = [{ nice: true }];
           m.save(function(err) {
             assert.equal(String(err), 'ValidationError: arr: BAM');
             m.arr.push(95);
@@ -1534,7 +1534,7 @@ describe('document', function() {
         }
       });
 
-      const MWSV = db.model('Test', new Schema({subs: [SchemaWithValidator]}));
+      const MWSV = db.model('Test', new Schema({ subs: [SchemaWithValidator] }));
       const m = new MWSV({
         subs: [{
           preference: 'xx'
@@ -1561,12 +1561,12 @@ describe('document', function() {
     let Post = null;
     let post = null;
 
-    InvalidateSchema = new Schema({prop: {type: String}},
-      {strict: false});
+    InvalidateSchema = new Schema({ prop: { type: String } },
+      { strict: false });
 
     Post = db.model('Test', InvalidateSchema);
     post = new Post();
-    post.set({baz: 'val'});
+    post.set({ baz: 'val' });
     const _err = post.invalidate('baz', 'validation failed for path {PATH}',
       'val', 'custom error');
     assert.ok(_err instanceof ValidationError);
@@ -1597,40 +1597,40 @@ describe('document', function() {
 
       before(function() {
         db.deleteModel(/^Test/);
-        S = db.model('Test', new Schema({_id: String}));
-        N = db.model('Test2', new Schema({_id: Number}));
-        O = db.model('Test3', new Schema({_id: Schema.ObjectId}));
-        B = db.model('Test4', new Schema({_id: Buffer}));
-        M = db.model('Test5', new Schema({name: String}, {_id: false}));
+        S = db.model('Test', new Schema({ _id: String }));
+        N = db.model('Test2', new Schema({ _id: Number }));
+        O = db.model('Test3', new Schema({ _id: Schema.ObjectId }));
+        B = db.model('Test4', new Schema({ _id: Buffer }));
+        M = db.model('Test5', new Schema({ name: String }, { _id: false }));
       });
 
       it('with string _ids', function(done) {
-        const s1 = new S({_id: 'one'});
-        const s2 = new S({_id: 'one'});
+        const s1 = new S({ _id: 'one' });
+        const s2 = new S({ _id: 'one' });
         assert.ok(s1.equals(s2));
         done();
       });
       it('with number _ids', function(done) {
-        const n1 = new N({_id: 0});
-        const n2 = new N({_id: 0});
+        const n1 = new N({ _id: 0 });
+        const n2 = new N({ _id: 0 });
         assert.ok(n1.equals(n2));
         done();
       });
       it('with ObjectId _ids', function(done) {
         let id = new mongoose.Types.ObjectId;
-        let o1 = new O({_id: id});
-        let o2 = new O({_id: id});
+        let o1 = new O({ _id: id });
+        let o2 = new O({ _id: id });
         assert.ok(o1.equals(o2));
 
         id = String(new mongoose.Types.ObjectId);
-        o1 = new O({_id: id});
-        o2 = new O({_id: id});
+        o1 = new O({ _id: id });
+        o2 = new O({ _id: id });
         assert.ok(o1.equals(o2));
         done();
       });
       it('with Buffer _ids', function(done) {
-        const n1 = new B({_id: 0});
-        const n2 = new B({_id: 0});
+        const n1 = new B({ _id: 0 });
+        const n2 = new B({ _id: 0 });
         assert.ok(n1.equals(n2));
         done();
       });
@@ -1686,14 +1686,14 @@ describe('document', function() {
             }
           });
 
-          doc.set('nested', {path: 'overwrite the entire nested object'});
+          doc.set('nested', { path: 'overwrite the entire nested object' });
           assert.equal(doc.nested.age, undefined);
           assert.equal(Object.keys(doc._doc.nested).length, 1);
           assert.equal(doc.nested.path, 'overwrite the entire nested object');
           assert.ok(doc.isModified('nested'));
 
           // vs merging using doc.set(object)
-          doc.set({test: 'Test', nested: {age: 4}});
+          doc.set({ test: 'Test', nested: { age: 4 } });
           assert.equal(doc.nested.path, '4overwrite the entire nested object');
           assert.equal(doc.nested.age, 4);
           assert.equal(Object.keys(doc._doc.nested).length, 2);
@@ -1708,7 +1708,7 @@ describe('document', function() {
           });
 
           // vs merging using doc.set(path, object, {merge: true})
-          doc.set('nested', {path: 'did not overwrite the nested object'}, {
+          doc.set('nested', { path: 'did not overwrite the nested object' }, {
             merge: true
           });
           assert.equal(doc.nested.path, '5did not overwrite the nested object');
@@ -1724,19 +1724,19 @@ describe('document', function() {
             }
           });
 
-          doc.set({test: 'Test', nested: {age: 5}});
+          doc.set({ test: 'Test', nested: { age: 5 } });
           assert.ok(!doc.isModified());
           assert.ok(!doc.isModified('test'));
           assert.ok(!doc.isModified('nested'));
           assert.ok(!doc.isModified('nested.age'));
 
-          doc.nested = {path: 'overwrite the entire nested object', age: 5};
+          doc.nested = { path: 'overwrite the entire nested object', age: 5 };
           assert.equal(doc.nested.age, 5);
           assert.equal(Object.keys(doc._doc.nested).length, 2);
           assert.equal(doc.nested.path, '5overwrite the entire nested object');
           assert.ok(doc.isModified('nested'));
 
-          doc.nested.deep = {x: 'Hank and Marie'};
+          doc.nested.deep = { x: 'Hank and Marie' };
           assert.equal(Object.keys(doc._doc.nested).length, 3);
           assert.equal(doc.nested.path, '5overwrite the entire nested object');
           assert.ok(doc.isModified('nested'));
@@ -1750,7 +1750,7 @@ describe('document', function() {
             }
           });
 
-          doc.set('nested.deep', {x: 'Hank and Marie'});
+          doc.set('nested.deep', { x: 'Hank and Marie' });
           assert.equal(Object.keys(doc._doc.nested).length, 2);
           assert.equal(Object.keys(doc._doc.nested.deep).length, 1);
           assert.ok(doc.isModified('nested'));
@@ -1777,7 +1777,7 @@ describe('document', function() {
 
         it('gh-1954', function(done) {
           const schema = new Schema({
-            schedule: [new Schema({open: Number, close: Number})]
+            schedule: [new Schema({ open: Number, close: Number })]
           });
 
           const M = db.model('BlogPost', schema);
@@ -1803,7 +1803,7 @@ describe('document', function() {
 
       describe('when overwriting with a document instance', function() {
         it('does not cause StackOverflows (gh-1234)', function(done) {
-          const doc = new TestDocument({nested: {age: 35}});
+          const doc = new TestDocument({ nested: { age: 35 } });
           doc.nested = doc.nested;
           assert.doesNotThrow(function() {
             doc.nested.age;
@@ -1820,7 +1820,7 @@ describe('document', function() {
       let M;
 
       beforeEach(function(done) {
-        const schema = new mongoose.Schema({v: Number});
+        const schema = new mongoose.Schema({ v: Number });
         schema.virtual('thang').set(function(v) {
           val = v;
         });
@@ -1831,22 +1831,22 @@ describe('document', function() {
       });
 
       it('works with objects', function(done) {
-        new M({thang: {}});
+        new M({ thang: {} });
         assert.deepEqual({}, val);
         done();
       });
       it('works with arrays', function(done) {
-        new M({thang: []});
+        new M({ thang: [] });
         assert.deepEqual([], val);
         done();
       });
       it('works with numbers', function(done) {
-        new M({thang: 4});
+        new M({ thang: 4 });
         assert.deepEqual(4, val);
         done();
       });
       it('works with strings', function(done) {
-        new M({thang: '3'});
+        new M({ thang: '3' });
         assert.deepEqual('3', val);
         done();
       });
@@ -1881,10 +1881,10 @@ describe('document', function() {
     it('works', function(done) {
       const Parent = db.model('Test', parentSchema);
 
-      const parent = new Parent({name: 'Hello'});
+      const parent = new Parent({ name: 'Hello' });
       parent.save(function(err, parent) {
         assert.ifError(err);
-        parent.children.push({counter: 0});
+        parent.children.push({ counter: 0 });
         parent.save(function(err, parent) {
           assert.ifError(err);
           parent.children[0].counter += 1;
@@ -1907,7 +1907,7 @@ describe('document', function() {
 
   describe('gh-1933', function() {
     it('works', function(done) {
-      const M = db.model('Test', new Schema({id: String, field: Number}));
+      const M = db.model('Test', new Schema({ id: String, field: Number }));
 
       M.create({}, function(error) {
         assert.ifError(error);
@@ -1927,7 +1927,7 @@ describe('document', function() {
   describe('gh-1638', function() {
     it('works', function(done) {
       const ItemChildSchema = new mongoose.Schema({
-        name: {type: String, required: true, default: 'hello'}
+        name: { type: String, required: true, default: 'hello' }
       });
 
       const ItemParentSchema = new mongoose.Schema({
@@ -1937,8 +1937,8 @@ describe('document', function() {
       const ItemParent = db.model('Parent', ItemParentSchema);
       const ItemChild = db.model('Child', ItemChildSchema);
 
-      const c1 = new ItemChild({name: 'first child'});
-      const c2 = new ItemChild({name: 'second child'});
+      const c1 = new ItemChild({ name: 'first child' });
+      const c2 = new ItemChild({ name: 'second child' });
 
       const p = new ItemParent({
         children: [c1, c2]
@@ -1967,7 +1967,7 @@ describe('document', function() {
 
       const Item = db.model('Test', ItemSchema);
 
-      const item = new Item({st: 1});
+      const item = new Item({ st: 1 });
 
       item.save(function(error) {
         assert.ifError(error);
@@ -2000,14 +2000,14 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const createdPerson = yield Person.create({name: 'Hafez'});
-        const removedPerson = yield Person.findOneAndRemove({_id: createdPerson._id});
+        const createdPerson = yield Person.create({ name: 'Hafez' });
+        const removedPerson = yield Person.findOneAndRemove({ _id: createdPerson._id });
 
         removedPerson.isNew = true;
 
         yield removedPerson.save();
 
-        const foundPerson = yield Person.findOne({_id: removedPerson._id});
+        const foundPerson = yield Person.findOne({ _id: removedPerson._id });
         assert.ok(foundPerson);
       });
     });
@@ -2017,7 +2017,7 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const createdPerson = yield Person.create({name: 'Hafez'});
+        const createdPerson = yield Person.create({ name: 'Hafez' });
 
         createdPerson.isNew = true;
 
@@ -2039,9 +2039,9 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const person = yield Person.create({name: 'Hafez'});
+        const person = yield Person.create({ name: 'Hafez' });
 
-        yield Person.deleteOne({_id: person._id});
+        yield Person.deleteOne({ _id: person._id });
 
         let threw = false;
         try {
@@ -2062,9 +2062,9 @@ describe('document', function() {
         const personSchema = new Schema({ name: String });
         const Person = db.model('Person', personSchema);
 
-        const person = yield Person.create({name: 'Hafez'});
+        const person = yield Person.create({ name: 'Hafez' });
 
-        yield Person.deleteOne({_id: person._id});
+        yield Person.deleteOne({ _id: person._id });
 
         person.name = 'Different Name';
 
@@ -2095,7 +2095,7 @@ describe('document', function() {
     personSchema.queue('fn');
 
     const Person = db.model('Person', personSchema);
-    new Person({name: 'Val'});
+    new Person({ name: 'Val' });
     assert.equal(calledName, 'Val');
     done();
   });
@@ -2103,7 +2103,7 @@ describe('document', function() {
   describe('bug fixes', function() {
     it('applies toJSON transform correctly for populated docs (gh-2910) (gh-2990)', function(done) {
       const parentSchema = mongoose.Schema({
-        c: {type: mongoose.Schema.Types.ObjectId, ref: 'Child'}
+        c: { type: mongoose.Schema.Types.ObjectId, ref: 'Child' }
       });
 
       let called = [];
@@ -2129,9 +2129,9 @@ describe('document', function() {
       const Child = db.model('Child', childSchema);
       const Parent = db.model('Parent', parentSchema);
 
-      Child.create({name: 'test'}, function(error, c) {
-        Parent.create({c: c._id}, function(error, p) {
-          Parent.findOne({_id: p._id}).populate('c').exec(function(error, p) {
+      Child.create({ name: 'test' }, function(error, c) {
+        Parent.create({ c: c._id }, function(error, p) {
+          Parent.findOne({ _id: p._id }).populate('c').exec(function(error, p) {
             let doc = p.toJSON();
             assert.equal(called.length, 1);
             assert.equal(called[0]._id.toString(), p._id.toString());
@@ -2144,7 +2144,7 @@ describe('document', function() {
 
             // JSON.stringify() passes field name, so make sure we don't treat
             // that as a param to toJSON (gh-2990)
-            doc = JSON.parse(JSON.stringify({parent: p})).parent;
+            doc = JSON.parse(JSON.stringify({ parent: p })).parent;
             assert.equal(called.length, 1);
             assert.equal(called[0]._id.toString(), p._id.toString());
             assert.equal(doc._id.toString(), p._id.toString());
@@ -2199,10 +2199,10 @@ describe('document', function() {
         otherStr: String
       });
 
-      const t = new M({myStr: {value: 'test'}});
+      const t = new M({ myStr: { value: 'test' } });
       assert.equal(t.myStr, 'test');
 
-      new M({otherStr: {value: 'test'}});
+      new M({ otherStr: { value: 'test' } });
       assert.ok(!t.otherStr);
 
       done();
@@ -2221,7 +2221,7 @@ describe('document', function() {
         const Model1 = db.model('Test', schema1);
         const Model2 = db.model('Test1', schema2);
 
-        const doc1 = new Model1({'data.email': 'some@example.com'});
+        const doc1 = new Model1({ 'data.email': 'some@example.com' });
         assert.equal(doc1.data.email, 'some@example.com');
         const doc2 = new Model2();
         doc2.set(doc1.data);
@@ -2238,9 +2238,9 @@ describe('document', function() {
       });
       const Model1 = db.model('Test', schema1);
 
-      const doc1 = new Model1({'data.email': 'some@example.com'});
+      const doc1 = new Model1({ 'data.email': 'some@example.com' });
       assert.equal(doc1.data.email, 'some@example.com');
-      const doc2 = new Model1({data: doc1.data});
+      const doc2 = new Model1({ data: doc1.data });
       assert.equal(doc2.data.email, 'some@example.com');
       done();
     });
@@ -2252,7 +2252,7 @@ describe('document', function() {
         }
       });
 
-      const t = new M({myStr: {thisIs: 'anObject'}});
+      const t = new M({ myStr: { thisIs: 'anObject' } });
       assert.ok(!t.myStr);
       t.validate(function(error) {
         assert.ok(error);
@@ -2264,7 +2264,7 @@ describe('document', function() {
       const userSchema = new mongoose.Schema({
         name: String,
         email: String
-      }, {_id: false, id: false});
+      }, { _id: false, id: false });
 
       let userHookCount = 0;
       userSchema.pre('save', function(next) {
@@ -2285,18 +2285,18 @@ describe('document', function() {
 
       const Event = db.model('Event', eventSchema);
 
-      const e = new Event({name: 'test', user: {name: 123, email: 'val'}});
+      const e = new Event({ name: 'test', user: { name: 123, email: 'val' } });
       e.save(function(error) {
         assert.ifError(error);
         assert.strictEqual(e.user.name, '123');
         assert.equal(eventHookCount, 1);
         assert.equal(userHookCount, 1);
 
-        Event.findOne({user: {name: '123', email: 'val'}}, function(err, doc) {
+        Event.findOne({ user: { name: '123', email: 'val' } }, function(err, doc) {
           assert.ifError(err);
           assert.ok(doc);
 
-          Event.findOne({user: {$in: [{name: '123', email: 'val'}]}}, function(err, doc) {
+          Event.findOne({ user: { $in: [{ name: '123', email: 'val' }] } }, function(err, doc) {
             assert.ifError(err);
             assert.ok(doc);
             done();
@@ -2308,8 +2308,8 @@ describe('document', function() {
     it('single embedded schemas with validation (gh-2689)', function(done) {
       const userSchema = new mongoose.Schema({
         name: String,
-        email: {type: String, required: true, match: /.+@.+/}
-      }, {_id: false, id: false});
+        email: { type: String, required: true, match: /.+@.+/ }
+      }, { _id: false, id: false });
 
       const eventSchema = new mongoose.Schema({
         user: userSchema,
@@ -2318,7 +2318,7 @@ describe('document', function() {
 
       const Event = db.model('Event', eventSchema);
 
-      const e = new Event({name: 'test', user: {}});
+      const e = new Event({ name: 'test', user: {} });
       let error = e.validateSync();
       assert.ok(error);
       assert.ok(error.errors['user.email']);
@@ -2337,8 +2337,8 @@ describe('document', function() {
     it('single embedded parent() (gh-5134)', function(done) {
       const userSchema = new mongoose.Schema({
         name: String,
-        email: {type: String, required: true, match: /.+@.+/}
-      }, {_id: false, id: false});
+        email: { type: String, required: true, match: /.+@.+/ }
+      }, { _id: false, id: false });
 
       const eventSchema = new mongoose.Schema({
         user: userSchema,
@@ -2347,7 +2347,7 @@ describe('document', function() {
 
       const Event = db.model('Event', eventSchema);
 
-      const e = new Event({name: 'test', user: {}});
+      const e = new Event({ name: 'test', user: {} });
       assert.strictEqual(e.user.parent(), e.user.ownerDocument());
 
       done();
@@ -2356,8 +2356,8 @@ describe('document', function() {
     it('single embedded schemas with markmodified (gh-2689)', function(done) {
       const userSchema = new mongoose.Schema({
         name: String,
-        email: {type: String, required: true, match: /.+@.+/}
-      }, {_id: false, id: false});
+        email: { type: String, required: true, match: /.+@.+/ }
+      }, { _id: false, id: false });
 
       const eventSchema = new mongoose.Schema({
         user: userSchema,
@@ -2366,7 +2366,7 @@ describe('document', function() {
 
       const Event = db.model('Event', eventSchema);
 
-      const e = new Event({name: 'test', user: {email: 'a@b'}});
+      const e = new Event({ name: 'test', user: { email: 'a@b' } });
       e.save(function(error, doc) {
         assert.ifError(error);
         assert.ok(doc);
@@ -2380,14 +2380,14 @@ describe('document', function() {
 
         const delta = doc.$__delta()[1];
         assert.deepEqual(delta, {
-          $set: {'user.name': 'Val'}
+          $set: { 'user.name': 'Val' }
         });
 
         doc.save(function(error) {
           assert.ifError(error);
-          Event.findOne({_id: doc._id}, function(error, doc) {
+          Event.findOne({ _id: doc._id }, function(error, doc) {
             assert.ifError(error);
-            assert.deepEqual(doc.user.toObject(), {email: 'a@b', name: 'Val'});
+            assert.deepEqual(doc.user.toObject(), { email: 'a@b', name: 'Val' });
             done();
           });
         });
@@ -2396,9 +2396,9 @@ describe('document', function() {
 
     it('single embedded schemas + update validators (gh-2689)', function(done) {
       const userSchema = new mongoose.Schema({
-        name: {type: String, default: 'Val'},
-        email: {type: String, required: true, match: /.+@.+/}
-      }, {_id: false, id: false});
+        name: { type: String, default: 'Val' },
+        email: { type: String, required: true, match: /.+@.+/ }
+      }, { _id: false, id: false });
 
       const eventSchema = new mongoose.Schema({
         user: userSchema,
@@ -2407,17 +2407,17 @@ describe('document', function() {
 
       const Event = db.model('Event', eventSchema);
 
-      const badUpdate = {$set: {'user.email': 'a'}};
-      const options = {runValidators: true};
+      const badUpdate = { $set: { 'user.email': 'a' } };
+      const options = { runValidators: true };
       Event.updateOne({}, badUpdate, options, function(error) {
         assert.ok(error);
         assert.equal(error.errors['user.email'].kind, 'regexp');
 
-        const nestedUpdate = {name: 'test'};
-        const options = {upsert: true, setDefaultsOnInsert: true};
+        const nestedUpdate = { name: 'test' };
+        const options = { upsert: true, setDefaultsOnInsert: true };
         Event.updateOne({}, nestedUpdate, options, function(error) {
           assert.ifError(error);
-          Event.findOne({name: 'test'}, function(error, ev) {
+          Event.findOne({ name: 'test' }, function(error, ev) {
             assert.ifError(error);
             assert.equal(ev.user.name, 'Val');
             done();
@@ -2502,7 +2502,7 @@ describe('document', function() {
 
       const Test = db.model('Test', testSchema);
 
-      Test.create([{}], {validateBeforeSave: false}, function(createError, docs) {
+      Test.create([{}], { validateBeforeSave: false }, function(createError, docs) {
         assert.equal(createError, null);
         const doc = docs[0];
         doc.other = 'something';
@@ -2519,12 +2519,12 @@ describe('document', function() {
 
       const Test = db.model('Test', testSchema);
 
-      Test.create([{}], {validateBeforeSave: false}, function(createError, docs) {
+      Test.create([{}], { validateBeforeSave: false }, function(createError, docs) {
         assert.equal(createError, null);
         const doc = docs[0];
         doc.other = 'something';
-        assert.equal(doc.validateSync(undefined, {validateModifiedOnly: true}), null);
-        doc.save({validateModifiedOnly: true}, function(error) {
+        assert.equal(doc.validateSync(undefined, { validateModifiedOnly: true }), null);
+        doc.save({ validateModifiedOnly: true }, function(error) {
           assert.equal(error, null);
           done();
         });
@@ -2536,12 +2536,12 @@ describe('document', function() {
 
       const Test = db.model('Test', testSchema);
 
-      Test.create([{title: 'title'}], {validateBeforeSave: false}, function(createError, docs) {
+      Test.create([{ title: 'title' }], { validateBeforeSave: false }, function(createError, docs) {
         assert.equal(createError, null);
         const doc = docs[0];
         doc.title = '';
-        assert.ok(doc.validateSync(undefined, {validateModifiedOnly: true}).errors);
-        doc.save({validateModifiedOnly: true}, function(error) {
+        assert.ok(doc.validateSync(undefined, { validateModifiedOnly: true }).errors);
+        doc.save({ validateModifiedOnly: true }, function(error) {
           assert.ok(error.errors);
           done();
         });
@@ -2612,7 +2612,7 @@ describe('document', function() {
       Child.create([{}, {}], function(error, docs) {
         assert.ifError(error);
         const obj = {
-          singleNested: {populateMeArray: [docs[0]._id, docs[1]._id]}
+          singleNested: { populateMeArray: [docs[0]._id, docs[1]._id] }
         };
         P.create(obj, function(error, doc) {
           assert.ifError(error);
@@ -2628,28 +2628,28 @@ describe('document', function() {
     });
 
     it('single embedded schemas with methods (gh-3534)', function(done) {
-      const personSchema = new Schema({name: String});
+      const personSchema = new Schema({ name: String });
       personSchema.methods.firstName = function() {
         return this.name.substr(0, this.name.indexOf(' '));
       };
 
-      const bandSchema = new Schema({leadSinger: personSchema});
+      const bandSchema = new Schema({ leadSinger: personSchema });
       const Band = db.model('Band', bandSchema);
 
-      const gnr = new Band({leadSinger: {name: 'Axl Rose'}});
+      const gnr = new Band({ leadSinger: { name: 'Axl Rose' } });
       assert.equal(gnr.leadSinger.firstName(), 'Axl');
       done();
     });
 
     it('single embedded schemas with models (gh-3535)', function(done) {
-      const personSchema = new Schema({name: String});
+      const personSchema = new Schema({ name: String });
       const Person = db.model('Person', personSchema);
 
-      const bandSchema = new Schema({leadSinger: personSchema});
+      const bandSchema = new Schema({ leadSinger: personSchema });
       const Band = db.model('Band', bandSchema);
 
-      const axl = new Person({name: 'Axl Rose'});
-      const gnr = new Band({leadSinger: axl});
+      const axl = new Person({ name: 'Axl Rose' });
+      const gnr = new Band({ leadSinger: axl });
 
       gnr.save(function(error) {
         assert.ifError(error);
@@ -2659,26 +2659,26 @@ describe('document', function() {
     });
 
     it('single embedded schemas with indexes (gh-3594)', function(done) {
-      const personSchema = new Schema({name: {type: String, unique: true}});
+      const personSchema = new Schema({ name: { type: String, unique: true } });
 
-      const bandSchema = new Schema({leadSinger: personSchema});
+      const bandSchema = new Schema({ leadSinger: personSchema });
 
       assert.equal(bandSchema.indexes().length, 1);
       const index = bandSchema.indexes()[0];
-      assert.deepEqual(index[0], {'leadSinger.name': 1});
+      assert.deepEqual(index[0], { 'leadSinger.name': 1 });
       assert.ok(index[1].unique);
       done();
     });
 
     it('removing single embedded docs (gh-3596)', function(done) {
-      const personSchema = new Schema({name: String});
+      const personSchema = new Schema({ name: String });
 
-      const bandSchema = new Schema({guitarist: personSchema, name: String});
+      const bandSchema = new Schema({ guitarist: personSchema, name: String });
       const Band = db.model('Band', bandSchema);
 
       const gnr = new Band({
         name: 'Guns N\' Roses',
-        guitarist: {name: 'Slash'}
+        guitarist: { name: 'Slash' }
       });
       gnr.save(function(error, gnr) {
         assert.ifError(error);
@@ -2692,14 +2692,14 @@ describe('document', function() {
     });
 
     it('setting single embedded docs (gh-3601)', function(done) {
-      const personSchema = new Schema({name: String});
+      const personSchema = new Schema({ name: String });
 
-      const bandSchema = new Schema({guitarist: personSchema, name: String});
+      const bandSchema = new Schema({ guitarist: personSchema, name: String });
       const Band = db.model('Band', bandSchema);
 
       const gnr = new Band({
         name: 'Guns N\' Roses',
-        guitarist: {name: 'Slash'}
+        guitarist: { name: 'Slash' }
       });
       const velvetRevolver = new Band({
         name: 'Velvet Revolver'
@@ -2713,19 +2713,19 @@ describe('document', function() {
     });
 
     it('single embedded docs init obeys strict mode (gh-3642)', function(done) {
-      const personSchema = new Schema({name: String});
+      const personSchema = new Schema({ name: String });
 
-      const bandSchema = new Schema({guitarist: personSchema, name: String});
+      const bandSchema = new Schema({ guitarist: personSchema, name: String });
       const Band = db.model('Band', bandSchema);
 
       const velvetRevolver = new Band({
         name: 'Velvet Revolver',
-        guitarist: {name: 'Slash', realName: 'Saul Hudson'}
+        guitarist: { name: 'Slash', realName: 'Saul Hudson' }
       });
 
       velvetRevolver.save(function(error) {
         assert.ifError(error);
-        const query = {name: 'Velvet Revolver'};
+        const query = { name: 'Velvet Revolver' };
         Band.collection.findOne(query, function(error, band) {
           assert.ifError(error);
           assert.ok(!band.guitarist.realName);
@@ -2736,14 +2736,14 @@ describe('document', function() {
 
     it('single embedded docs post hooks (gh-3679)', function(done) {
       const postHookCalls = [];
-      const personSchema = new Schema({name: String});
+      const personSchema = new Schema({ name: String });
       personSchema.post('save', function() {
         postHookCalls.push(this);
       });
 
-      const bandSchema = new Schema({guitarist: personSchema, name: String});
+      const bandSchema = new Schema({ guitarist: personSchema, name: String });
       const Band = db.model('Band', bandSchema);
-      const obj = {name: 'Guns N\' Roses', guitarist: {name: 'Slash'}};
+      const obj = { name: 'Guns N\' Roses', guitarist: { name: 'Slash' } };
 
       Band.create(obj, function(error) {
         assert.ifError(error);
@@ -2756,7 +2756,7 @@ describe('document', function() {
     });
 
     it('single embedded docs .set() (gh-3686)', function(done) {
-      const personSchema = new Schema({name: String, realName: String});
+      const personSchema = new Schema({ name: String, realName: String });
 
       const bandSchema = new Schema({
         guitarist: personSchema,
@@ -2765,7 +2765,7 @@ describe('document', function() {
       const Band = db.model('Band', bandSchema);
       const obj = {
         name: 'Guns N\' Roses',
-        guitarist: {name: 'Slash', realName: 'Saul Hudson'}
+        guitarist: { name: 'Slash', realName: 'Saul Hudson' }
       };
 
       Band.create(obj, function(error, gnr) {
@@ -2780,7 +2780,7 @@ describe('document', function() {
     });
 
     it('single embedded docs with arrays pre hooks (gh-3680)', function(done) {
-      const childSchema = new Schema({count: Number});
+      const childSchema = new Schema({ count: Number });
 
       let preCalls = 0;
       childSchema.pre('save', function(next) {
@@ -2797,7 +2797,7 @@ describe('document', function() {
       });
 
       const Parent = db.model('Parent', ParentSchema);
-      const obj = {singleNested: {children: [{count: 0}]}};
+      const obj = { singleNested: { children: [{ count: 0 }] } };
       Parent.create(obj, function(error) {
         assert.ifError(error);
         assert.equal(preCalls, 1);
@@ -2806,12 +2806,12 @@ describe('document', function() {
     });
 
     it('nested single embedded doc validation (gh-3702)', function(done) {
-      const childChildSchema = new Schema({count: {type: Number, min: 1}});
-      const childSchema = new Schema({child: childChildSchema});
-      const parentSchema = new Schema({child: childSchema});
+      const childChildSchema = new Schema({ count: { type: Number, min: 1 } });
+      const childSchema = new Schema({ child: childChildSchema });
+      const parentSchema = new Schema({ child: childSchema });
 
       const Parent = db.model('Parent', parentSchema);
-      const obj = {child: {child: {count: 0}}};
+      const obj = { child: { child: { count: 0 } } };
       Parent.create(obj, function(error) {
         assert.ok(error);
         assert.ok(/ValidationError/.test(error.toString()));
@@ -2820,7 +2820,7 @@ describe('document', function() {
     });
 
     it('handles virtuals with dots correctly (gh-3618)', function(done) {
-      const testSchema = new Schema({nested: {type: Object, default: {}}});
+      const testSchema = new Schema({ nested: { type: Object, default: {} } });
       testSchema.virtual('nested.test').get(function() {
         return true;
       });
@@ -2829,15 +2829,15 @@ describe('document', function() {
 
       const test = new Test();
 
-      let doc = test.toObject({getters: true, virtuals: true});
+      let doc = test.toObject({ getters: true, virtuals: true });
       delete doc._id;
       delete doc.id;
-      assert.deepEqual(doc, {nested: {test: true}});
+      assert.deepEqual(doc, { nested: { test: true } });
 
-      doc = test.toObject({getters: false, virtuals: true});
+      doc = test.toObject({ getters: false, virtuals: true });
       delete doc._id;
       delete doc.id;
-      assert.deepEqual(doc, {nested: {test: true}});
+      assert.deepEqual(doc, { nested: { test: true } });
       done();
     });
 
@@ -2858,13 +2858,13 @@ describe('document', function() {
 
       const MyModel = db.model('Test', schema);
 
-      const doc = {array: [{2: {}}]};
+      const doc = { array: [{ 2: {} }] };
       MyModel.collection.insertOne(doc, function(error) {
         assert.ifError(error);
 
-        MyModel.findOne({_id: doc._id}, function(error, doc) {
+        MyModel.findOne({ _id: doc._id }, function(error, doc) {
           assert.ifError(error);
-          doc.array.push({2: {}});
+          doc.array.push({ 2: {} });
           doc.save(function(error) {
             assert.ifError(error);
             done();
@@ -2880,17 +2880,17 @@ describe('document', function() {
 
       const parentSchema = new Schema({
         name: String,
-        children: [{type: ObjectId, ref: 'Child'}]
+        children: [{ type: ObjectId, ref: 'Child' }]
       });
 
       const Child = db.model('Child', childSchema);
       const Parent = db.model('Parent', parentSchema);
 
-      Child.create({name: 'Luke Skywalker'}, function(error, child) {
+      Child.create({ name: 'Luke Skywalker' }, function(error, child) {
         assert.ifError(error);
-        const doc = {name: 'Darth Vader', children: [child._id]};
+        const doc = { name: 'Darth Vader', children: [child._id] };
         Parent.create(doc, function(error, doc) {
-          Parent.findOne({_id: doc._id}, function(error, doc) {
+          Parent.findOne({ _id: doc._id }, function(error, doc) {
             assert.ifError(error);
             assert.ok(doc);
             doc.populate('children').execPopulate().then(function(doc) {
@@ -2908,14 +2908,14 @@ describe('document', function() {
         _id: Number,
         name: String,
         age: Number,
-        friends: [{type: Number, ref: 'Person'}]
+        friends: [{ type: Number, ref: 'Person' }]
       });
 
       const Person = db.model('Person', personSchema);
 
       const people = [
-        {_id: 0, name: 'Alice'},
-        {_id: 1, name: 'Bob'}
+        { _id: 0, name: 'Alice' },
+        { _id: 1, name: 'Bob' }
       ];
 
       Person.create(people, function(error, people) {
@@ -3878,7 +3878,7 @@ describe('document', function() {
       const Model = db.model('Test', schema);
 
       const object = new Model();
-      object._id = {key1: 'foo', key2: 'bar'};
+      object._id = { key1: 'foo', key2: 'bar' };
       object.save().
         then(function(obj) {
           obj.content = 'Hello';
@@ -4220,7 +4220,7 @@ describe('document', function() {
       const ParentSchema = new mongoose.Schema({
         name: String,
         child: { type: Schema.Types.ObjectId, ref: 'Child' }
-      }, {shardKey: {child: 1, _id: 1}});
+      }, { shardKey: { child: 1, _id: 1 } });
 
       const ParentModel = db.model('Parent', ParentSchema);
 
@@ -4368,9 +4368,9 @@ describe('document', function() {
         }
       };
 
-      const schemaWithTimestamps = new Schema(schemaDefinition, {timestamps: {createdAt: 'misc.createdAt'}});
+      const schemaWithTimestamps = new Schema(schemaDefinition, { timestamps: { createdAt: 'misc.createdAt' } });
       const PersonWithTimestamps = db.model('Person_timestamps', schemaWithTimestamps);
-      const dude = new PersonWithTimestamps({ name: 'Keanu', misc: {hometown: 'Beirut'} });
+      const dude = new PersonWithTimestamps({ name: 'Keanu', misc: { hometown: 'Beirut' } });
       assert.equal(dude.misc.isAlive, true);
 
       done();
@@ -4630,11 +4630,11 @@ describe('document', function() {
       const Parent = db.model('Parent', parentSchema);
 
       const grandchild = new Grandchild();
-      const child = new Child({grandchild: grandchild});
+      const child = new Child({ grandchild: grandchild });
 
       assert.equal(child.grandchild.foo(), 'bar');
 
-      const p = new Parent({children: [child]});
+      const p = new Parent({ children: [child] });
 
       assert.equal(child.grandchild.foo(), 'bar');
       assert.equal(p.children[0].grandchild.foo(), 'bar');
@@ -4789,7 +4789,7 @@ describe('document', function() {
       assert.ok(error);
       assert.equal(error.errors['name'].reason.message, 'woops!');
 
-      new M({ name: 'test'}).validate(function(error) {
+      new M({ name: 'test' }).validate(function(error) {
         assert.ok(error);
         assert.equal(error.errors['name'].reason.message, 'woops!');
         done();
@@ -4804,7 +4804,7 @@ describe('document', function() {
 
       const Model = db.model('Model', schema);
 
-      Model.create({ hook: 'test '}, function(error) {
+      Model.create({ hook: 'test ' }, function(error) {
         assert.ifError(error);
         done();
       });
@@ -4990,7 +4990,7 @@ describe('document', function() {
         });
 
       const TestModel = db.model('Test', TestSchema);
-      const t = new TestModel({'a.b.c': 5});
+      const t = new TestModel({ 'a.b.c': 5 });
       assert.equal(t.a.b.c, 5);
 
       done();
@@ -5161,7 +5161,7 @@ describe('document', function() {
     it('push() onto a nested doc array (gh-6398)', function() {
       const schema = new mongoose.Schema({
         name: String,
-        array: [[{key: String, value: Number}]]
+        array: [[{ key: String, value: Number }]]
       });
 
       const Model = db.model('Test', schema);
@@ -5188,7 +5188,7 @@ describe('document', function() {
 
     it('push() onto a triple nested doc array (gh-6602) (gh-6398)', function() {
       const schema = new mongoose.Schema({
-        array: [[[{key: String, value: Number}]]]
+        array: [[[{ key: String, value: Number }]]]
       });
 
       const Model = db.model('Test', schema);
@@ -5227,7 +5227,7 @@ describe('document', function() {
 
     it('setting populated path with typeKey (gh-5313)', function(done) {
       const personSchema = Schema({
-        name: {$type: String},
+        name: { $type: String },
         favorite: { $type: Schema.Types.ObjectId, ref: 'Book' },
         books: [{ $type: Schema.Types.ObjectId, ref: 'Book' }]
       }, { typeKey: '$type' });
@@ -5598,7 +5598,7 @@ describe('document', function() {
       const referenceA = new Referrer();
       const referenceB = new Referrer();
 
-      const referrerA = new Referrer({reference: [referenceA]});
+      const referrerA = new Referrer({ reference: [referenceA] });
       const referrerB = new Referrer();
       const referrerC = new Referrer();
       const referrerD = new Referrer();
@@ -6086,7 +6086,7 @@ describe('document', function() {
 
       return co(function*() {
         yield Model.create({});
-        const doc1 = yield Model.findOne({}).select({_id: 1});
+        const doc1 = yield Model.findOne({}).select({ _id: 1 });
         yield doc1.save();
 
         // Should not throw
@@ -6172,11 +6172,11 @@ describe('document', function() {
     it('modifying unselected nested object (gh-5800)', function() {
       const MainSchema = new mongoose.Schema({
         a: {
-          b: {type: String, default: 'some default'},
-          c: {type: Number, default: 0},
-          d: {type: String}
+          b: { type: String, default: 'some default' },
+          c: { type: Number, default: 0 },
+          d: { type: String }
         },
-        e: {type: String}
+        e: { type: String }
       });
 
       MainSchema.pre('save', function(next) {
@@ -6372,7 +6372,7 @@ describe('document', function() {
       }
 
       const TestDefaultsWithFunction = db.model('Test', new Schema({
-        randomID: {type: Number, default: generateRandomID}
+        randomID: { type: Number, default: generateRandomID }
       }));
 
       const post = new TestDefaultsWithFunction;
@@ -6687,7 +6687,7 @@ describe('document', function() {
   });
 
   it('does not save duplicate items after two saves (gh-6900)', function() {
-    const M = db.model('Test', {items: [{name: String}]});
+    const M = db.model('Test', { items: [{ name: String }] });
     const doc = new M();
     doc.items.push({ name: '1' });
 
@@ -7629,7 +7629,7 @@ describe('document', function() {
 
     const SubIssueSchema = new mongoose.Schema({
       checklist: [{
-        completed: {$type: Boolean, default: false}
+        completed: { $type: Boolean, default: false }
       }]
     }, opts);
     IssueModel.discriminator('gh7704_sub', SubIssueSchema);
@@ -8242,7 +8242,7 @@ describe('document', function() {
     const subdocSchema = mongoose.Schema({ a: String });
     const schema = mongoose.Schema({ subdocs: { type: [subdocSchema] } });
     const Model = db.model('Test', schema);
-    const data = { _id: new mongoose.Types.ObjectId(), subdocs: [{a: 'a'}] };
+    const data = { _id: new mongoose.Types.ObjectId(), subdocs: [{ a: 'a' }] };
     const doc = new Model();
     doc.init(data);
     require('util').inspect(doc.subdocs);
diff --git a/test/document.unit.test.js b/test/document.unit.test.js
index 86923f2c0b5..874c93674d0 100644
--- a/test/document.unit.test.js
+++ b/test/document.unit.test.js
@@ -15,7 +15,7 @@ describe('sharding', function() {
   it('should handle shard keys properly (gh-2127)', function(done) {
     const mockSchema = {
       options: {
-        shardKey: {date: 1}
+        shardKey: { date: 1 }
       }
     };
     const Stub = function() {
@@ -25,7 +25,7 @@ describe('sharding', function() {
     Stub.prototype.__proto__ = mongoose.Document.prototype;
     const d = new Stub();
     const currentTime = new Date();
-    d._doc = {date: currentTime};
+    d._doc = { date: currentTime };
 
     storeShard.call(d);
     assert.equal(d.$__.shardval.date, currentTime);
@@ -39,10 +39,10 @@ describe('toObject()', function() {
   beforeEach(function() {
     Stub = function() {
       const schema = this.schema = {
-        options: {toObject: {minimize: false, virtuals: true}},
-        virtuals: {virtual: 'test'}
+        options: { toObject: { minimize: false, virtuals: true } },
+        virtuals: { virtual: 'test' }
       };
-      this._doc = {empty: {}};
+      this._doc = { empty: {} };
       this.get = function(path) { return schema.virtuals[path]; };
       this.$__ = {};
     };
@@ -51,13 +51,13 @@ describe('toObject()', function() {
 
   it('should inherit options from schema', function(done) {
     const d = new Stub();
-    assert.deepEqual(d.toObject(), {empty: {}, virtual: 'test'});
+    assert.deepEqual(d.toObject(), { empty: {}, virtual: 'test' });
     done();
   });
 
   it('can overwrite schema-set default options', function(done) {
     const d = new Stub();
-    assert.deepEqual(d.toObject({minimize: true, virtuals: false}), {});
+    assert.deepEqual(d.toObject({ minimize: true, virtuals: false }), {});
     done();
   });
 
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index cfb566480cc..ffc834b8da5 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -19,11 +19,11 @@ describe('ValidationError', function() {
   describe('#infiniteRecursion', function() {
     it('does not cause RangeError (gh-1834)', function(done) {
       const SubSchema = new Schema({
-        name: {type: String, required: true},
+        name: { type: String, required: true },
         contents: [new Schema({
-          key: {type: String, required: true},
-          value: {type: String, required: true}
-        }, {_id: false})]
+          key: { type: String, required: true },
+          value: { type: String, required: true }
+        }, { _id: false })]
       });
 
       const M = mongoose.model('SubSchema', SubSchema);
@@ -31,7 +31,7 @@ describe('ValidationError', function() {
       const model = new M({
         name: 'Model',
         contents: [
-          {key: 'foo'}
+          { key: 'foo' }
         ]
       });
 
@@ -47,7 +47,7 @@ describe('ValidationError', function() {
   describe('#minDate', function() {
     it('causes a validation error', function(done) {
       const MinSchema = new Schema({
-        appointmentDate: {type: Date, min: Date.now}
+        appointmentDate: { type: Date, min: Date.now }
       });
 
       const M = mongoose.model('MinSchema', MinSchema);
@@ -74,7 +74,7 @@ describe('ValidationError', function() {
   describe('#maxDate', function() {
     it('causes a validation error', function(done) {
       const MaxSchema = new Schema({
-        birthdate: {type: Date, max: Date.now}
+        birthdate: { type: Date, max: Date.now }
       });
 
       const M = mongoose.model('MaxSchema', MaxSchema);
@@ -101,7 +101,7 @@ describe('ValidationError', function() {
   describe('#minlength', function() {
     it('causes a validation error', function(done) {
       const AddressSchema = new Schema({
-        postalCode: {type: String, minlength: 5}
+        postalCode: { type: String, minlength: 5 }
       });
 
       const Address = mongoose.model('MinLengthAddress', AddressSchema);
@@ -155,7 +155,7 @@ describe('ValidationError', function() {
   describe('#maxlength', function() {
     it('causes a validation error', function(done) {
       const AddressSchema = new Schema({
-        postalCode: {type: String, maxlength: 10}
+        postalCode: { type: String, maxlength: 10 }
       });
 
       const Address = mongoose.model('MaxLengthAddress', AddressSchema);
@@ -182,8 +182,8 @@ describe('ValidationError', function() {
   describe('#toString', function() {
     it('does not cause RangeError (gh-1296)', function(done) {
       const ASchema = new Schema({
-        key: {type: String, required: true},
-        value: {type: String, required: true}
+        key: { type: String, required: true },
+        value: { type: String, required: true }
       });
 
       const BSchema = new Schema({
@@ -192,7 +192,7 @@ describe('ValidationError', function() {
 
       const M = mongoose.model('A', BSchema);
       const m = new M;
-      m.contents.push({key: 'asdf'});
+      m.contents.push({ key: 'asdf' });
       m.validate(function(err) {
         assert.doesNotThrow(function() {
           String(err);
@@ -204,7 +204,7 @@ describe('ValidationError', function() {
 
   describe('formatMessage', function() {
     it('replaces properties in a message', function() {
-      const props = {base: 'eggs', topping: 'bacon'};
+      const props = { base: 'eggs', topping: 'bacon' };
       const message = 'I had {BASE} and {TOPPING} for breakfast';
 
       const result = ValidatorError.prototype.formatMessage(message, props);
diff --git a/test/gh-1408.test.js b/test/gh-1408.test.js
index 7a2d86cef57..324aca5d362 100644
--- a/test/gh-1408.test.js
+++ b/test/gh-1408.test.js
@@ -19,10 +19,10 @@ describe('documents should not be converted to _id (gh-1408)', function() {
     const db = start();
 
     const PreferenceSchema = new Schema({
-      _id: {type: Schema.ObjectId, auto: true},
-      preference: {type: String, required: true},
-      value: {type: Schema.Types.Mixed}
-    }, {versionKey: false});
+      _id: { type: Schema.ObjectId, auto: true },
+      preference: { type: String, required: true },
+      value: { type: Schema.Types.Mixed }
+    }, { versionKey: false });
 
     const BrandSchema = new Schema({
       settings: {
@@ -35,10 +35,10 @@ describe('documents should not be converted to _id (gh-1408)', function() {
     const a = new A({
       settings: {
         preferences:
-         [{preference: 'group_colors', value: false},
-           {preference: 'can_force_orders', value: true},
-           {preference: 'hide_from_buyers', value: true},
-           {preference: 'no_orders', value: ''}
+         [{ preference: 'group_colors', value: false },
+           { preference: 'can_force_orders', value: true },
+           { preference: 'hide_from_buyers', value: true },
+           { preference: 'no_orders', value: '' }
          ]
       }
     });
@@ -52,17 +52,17 @@ describe('documents should not be converted to _id (gh-1408)', function() {
         const newData = {
           settings: {
             preferences:
-             [{preference: 'group_colors', value: true},
-               {preference: 'can_force_orders', value: true},
-               {preference: 'custom_csv', value: ''},
-               {preference: 'hide_from_buyers', value: false},
-               {preference: 'nozoom', value: false},
-               {preference: 'no_orders', value: false}
+             [{ preference: 'group_colors', value: true },
+               { preference: 'can_force_orders', value: true },
+               { preference: 'custom_csv', value: '' },
+               { preference: 'hide_from_buyers', value: false },
+               { preference: 'nozoom', value: false },
+               { preference: 'no_orders', value: false }
              ]
           }
         };
 
-        doc.set('settings', newData.settings, {merge: true});
+        doc.set('settings', newData.settings, { merge: true });
         doc.markModified('settings'); // <== this caused the bug
         doc.save(function(err) {
           if (err) return done(err);
diff --git a/test/helpers/getFunctionName.test.js b/test/helpers/getFunctionName.test.js
index d3b7dbe3bdb..fc875252a77 100644
--- a/test/helpers/getFunctionName.test.js
+++ b/test/helpers/getFunctionName.test.js
@@ -5,7 +5,7 @@ const getFunctionName = require('../../lib/helpers/getFunctionName');
 
 describe('getFunctionName', () => {
   it('return fn.name', () => {
-    assert.equal(getFunctionName({ name: 'fnName'}), 'fnName');
+    assert.equal(getFunctionName({ name: 'fnName' }), 'fnName');
   });
 
   it('return function name', () => {
diff --git a/test/helpers/populate.getSchemaTypes.test.js b/test/helpers/populate.getSchemaTypes.test.js
index 01472c9c3c1..b13dd9da84f 100644
--- a/test/helpers/populate.getSchemaTypes.test.js
+++ b/test/helpers/populate.getSchemaTypes.test.js
@@ -12,7 +12,7 @@ describe('getSchemaTypes', function() {
         type: String,
         required: true
       }
-    }, {discriminatorKey: 'type'});
+    }, { discriminatorKey: 'type' });
 
     const ItemBookSchema = new Schema({
       author: {
@@ -67,7 +67,7 @@ describe('getSchemaTypes', function() {
         type: String,
         required: true
       }
-    }, {discriminatorKey: 'type'});
+    }, { discriminatorKey: 'type' });
 
     const ItemBookSchema = new Schema({
       author: {
diff --git a/test/helpers/populate.getVirtual.test.js b/test/helpers/populate.getVirtual.test.js
index 7e2c1457b60..76b7d6cf852 100644
--- a/test/helpers/populate.getVirtual.test.js
+++ b/test/helpers/populate.getVirtual.test.js
@@ -9,7 +9,7 @@ describe('getVirtual', function() {
     // Generate Embedded Discriminators
     const eventSchema = new Schema(
       { message: String },
-      { discriminatorKey: 'kind'}
+      { discriminatorKey: 'kind' }
     );
 
     const batchSchema = new Schema({
@@ -56,7 +56,7 @@ describe('getVirtual', function() {
 
     // *** Adding Nested Layer and adding virtual to schema of nestedLayer
     const nestedLayerSchema = new Schema({ users: [Number] }, {
-      toJSON: { virtuals: true},
+      toJSON: { virtuals: true },
       toObject: { virtuals: true }
     });
 
@@ -71,8 +71,8 @@ describe('getVirtual', function() {
       element: { type: String },
       nestedLayer: nestedLayerSchema
     }, {
-      toJSON: { virtuals: true},
-      toObject: { virtuals: true}
+      toJSON: { virtuals: true },
+      toObject: { virtuals: true }
     });
 
     docArray.discriminator('Clicked', clickedSchema);
@@ -87,15 +87,15 @@ describe('getVirtual', function() {
   });
 
   it('handles multiple calls with discriminator under doc array (gh-6644)', function(done) {
-    const eventSchema = new Schema({ message: String }, { discriminatorKey: 'kind'});
+    const eventSchema = new Schema({ message: String }, { discriminatorKey: 'kind' });
 
     const batchSchema = new Schema({ events: [eventSchema] });
 
     const docArray = batchSchema.path('events');
 
     const clickedSchema = new Schema({ element: { type: String }, users: [{}] }, {
-      toJSON: { virtuals: true},
-      toObject: { virtuals: true}
+      toJSON: { virtuals: true },
+      toObject: { virtuals: true }
     });
 
     clickedSchema.virtual('users_$', {
diff --git a/test/index.test.js b/test/index.test.js
index 40127998758..e62d17d48ce 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -382,14 +382,14 @@ describe('mongoose module:', function() {
     });
 
     const eventSchema = new m.Schema({
-      kind: {type: String}
+      kind: { type: String }
     }, { discriminatorKey: 'kind' });
 
     const testEventSchema = new m.Schema({
       inner: {
         type: new mongoose.Schema({
           _id: false,
-          bool: {type: Boolean, required: true}
+          bool: { type: Boolean, required: true }
         })
       }
     });
@@ -596,15 +596,15 @@ describe('mongoose module:', function() {
     });
 
     it('returns the model at creation', function(done) {
-      const Named = mongoose.model('Named', new Schema({name: String}));
+      const Named = mongoose.model('Named', new Schema({ name: String }));
       const n1 = new Named();
       assert.equal(n1.name, null);
-      const n2 = new Named({name: 'Peter Bjorn'});
+      const n2 = new Named({ name: 'Peter Bjorn' });
       assert.equal(n2.name, 'Peter Bjorn');
 
-      const schema = new Schema({number: Number});
+      const schema = new Schema({ number: Number });
       const Numbered = mongoose.model('Numbered', schema, collection);
-      const n3 = new Numbered({number: 1234});
+      const n3 = new Numbered({ number: 1234 });
       assert.equal(n3.number.valueOf(), 1234);
       done();
     });
@@ -660,7 +660,7 @@ describe('mongoose module:', function() {
       describe('when model name already exists', function() {
         it('returns a new uncached model', function(done) {
           const m = new Mongoose;
-          const s1 = new Schema({a: []});
+          const s1 = new Schema({ a: [] });
           const name = 'non-cached-collection-name';
           const A = m.model(name, s1);
           const B = m.model(name);
@@ -677,8 +677,8 @@ describe('mongoose module:', function() {
     describe('passing object literal schemas', function() {
       it('works', function(done) {
         const m = new Mongoose;
-        const A = m.model('A', {n: [{age: 'number'}]});
-        const a = new A({n: [{age: '47'}]});
+        const A = m.model('A', { n: [{ age: 'number' }] });
+        const a = new A({ n: [{ age: '47' }] });
         assert.strictEqual(47, a.n[0].age);
         done();
       });
diff --git a/test/model.aggregate.test.js b/test/model.aggregate.test.js
index 2272f23fe30..9df59434e4e 100644
--- a/test/model.aggregate.test.js
+++ b/test/model.aggregate.test.js
@@ -29,8 +29,8 @@ mongoose.model('Aggregate', userSchema);
 describe('model aggregate', function() {
   this.timeout(process.env.TRAVIS ? 8000 : 4500);
 
-  const group = {$group: {_id: null, maxAge: {$max: '$age'}}};
-  const project = {$project: {maxAge: 1, _id: 0}};
+  const group = { $group: { _id: null, maxAge: { $max: '$age' } } };
+  const project = { $project: { maxAge: 1, _id: 0 } };
   let db, A, maxAge;
 
   let mongo26_or_greater = false;
@@ -47,7 +47,7 @@ describe('model aggregate', function() {
     for (let i = 0; i < num; ++i) {
       const age = Math.random() * 100 | 0;
       maxAge = Math.max(maxAge, age);
-      docs.push({author: authors[i % authors.length], age: age});
+      docs.push({ author: authors[i % authors.length], age: age });
     }
 
     A.create(docs, function(err) {
diff --git a/test/model.create.test.js b/test/model.create.test.js
index 51630b0a654..567742615ea 100644
--- a/test/model.create.test.js
+++ b/test/model.create.test.js
@@ -36,7 +36,7 @@ describe('model', function() {
     });
 
     it('accepts an array and returns an array', function(done) {
-      B.create([{title: 'hi'}, {title: 'bye'}], function(err, posts) {
+      B.create([{ title: 'hi' }, { title: 'bye' }], function(err, posts) {
         assert.ifError(err);
 
         assert.ok(posts instanceof Array);
@@ -79,7 +79,7 @@ describe('model', function() {
     });
 
     it('returns a promise', function(done) {
-      const p = B.create({title: 'returns promise'});
+      const p = B.create({ title: 'returns promise' });
       assert.ok(p instanceof mongoose.Promise);
       done();
     });
@@ -107,10 +107,10 @@ describe('model', function() {
       });
       const MWPSH = db.model('mwpsh', SchemaWithPreSaveHook);
       MWPSH.create([
-        {preference: 'xx'},
-        {preference: 'yy'},
-        {preference: '1'},
-        {preference: '2'}
+        { preference: 'xx' },
+        { preference: 'yy' },
+        { preference: '1' },
+        { preference: '2' }
       ], function(err, docs) {
         assert.ifError(err);
 
@@ -133,7 +133,7 @@ describe('model', function() {
 
     describe('callback is optional', function() {
       it('with one doc', function(done) {
-        const p = B.create({title: 'optional callback'});
+        const p = B.create({ title: 'optional callback' });
         p.then(function(doc) {
           assert.equal(doc.title, 'optional callback');
           done();
@@ -141,7 +141,7 @@ describe('model', function() {
       });
 
       it('with more than one doc', function(done) {
-        const p = B.create({title: 'optional callback 2'}, {title: 'orient expressions'});
+        const p = B.create({ title: 'optional callback 2' }, { title: 'orient expressions' });
         p.then(function(docs) {
           assert.equal(docs.length, 2);
           const doc1 = docs[0];
@@ -153,7 +153,7 @@ describe('model', function() {
       });
 
       it('with array of docs', function(done) {
-        const p = B.create([{title: 'optional callback3'}, {title: '3'}]);
+        const p = B.create([{ title: 'optional callback3' }, { title: '3' }]);
         p.then(function(docs) {
           assert.ok(docs instanceof Array);
           assert.equal(docs.length, 2);
@@ -166,9 +166,9 @@ describe('model', function() {
       });
 
       it('and should reject promise on error', function(done) {
-        const p = B.create({title: 'optional callback 4'});
+        const p = B.create({ title: 'optional callback 4' });
         p.then(function(doc) {
-          const p2 = B.create({_id: doc._id});
+          const p2 = B.create({ _id: doc._id });
           p2.then(function() {
             assert(false);
           }, function(err) {
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index ed80ad596dc..2c05cbcc876 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -22,14 +22,14 @@ function BaseSchema() {
 
   this.add({
     name: String,
-    createdAt: {type: Date, default: Date.now}
+    createdAt: { type: Date, default: Date.now }
   });
 }
 util.inherits(BaseSchema, Schema);
 
 const EventSchema = new BaseSchema();
 const ImpressionEventSchema = new BaseSchema();
-const ConversionEventSchema = new BaseSchema({revenue: Number});
+const ConversionEventSchema = new BaseSchema({ revenue: Number });
 const SecretEventSchema = new BaseSchema({ secret: { type: String, select: false } });
 
 describe('model', function() {
@@ -71,7 +71,7 @@ describe('model', function() {
           DiscCustomEventSchema);
         const ContainerSchema = new Schema({
           title: String,
-          events: [{type: Schema.Types.ObjectId, ref: 'base-custom-event'}]
+          events: [{ type: Schema.Types.ObjectId, ref: 'base-custom-event' }]
         });
         ContainerModel = db.model('container-event-model', ContainerSchema);
       });
@@ -109,9 +109,9 @@ describe('model', function() {
 
     describe('find', function() {
       it('hydrates correct models', function(done) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -140,9 +140,9 @@ describe('model', function() {
       });
 
       const checkHydratesCorrectModels = function(fields, done) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -175,14 +175,14 @@ describe('model', function() {
       });
 
       it('hydrates correct models when fields selection set as object', function(done) {
-        checkHydratesCorrectModels({name: 1}, done);
+        checkHydratesCorrectModels({ name: 1 }, done);
       });
 
       describe('discriminator model only finds documents of its type', function() {
 
         describe('using "ModelDiscriminator#findById"', function() {
           it('to find a document of the appropriate discriminator', function(done) {
-            const impressionEvent = new ImpressionEvent({name: 'Impression event'});
+            const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
             impressionEvent.save(function(err) {
               assert.ifError(err);
 
@@ -213,9 +213,9 @@ describe('model', function() {
 
         describe('using "ModelDiscriminator#find"', function() {
           it('to find documents of the appropriate discriminator', function(done) {
-            const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-            const conversionEvent1 = new ConversionEvent({name: 'Conversion event 1', revenue: 1});
-            const conversionEvent2 = new ConversionEvent({name: 'Conversion event 2', revenue: 2});
+            const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+            const conversionEvent1 = new ConversionEvent({ name: 'Conversion event 1', revenue: 1 });
+            const conversionEvent2 = new ConversionEvent({ name: 'Conversion event 2', revenue: 2 });
             impressionEvent.save(function(err) {
               assert.ifError(err);
               conversionEvent1.save(function(err) {
@@ -223,16 +223,16 @@ describe('model', function() {
                 conversionEvent2.save(function(err) {
                   assert.ifError(err);
                   // doesn't find anything since we're querying for an impression id
-                  const query = ConversionEvent.find({_id: impressionEvent._id});
+                  const query = ConversionEvent.find({ _id: impressionEvent._id });
                   assert.equal(query.op, 'find');
-                  assert.deepEqual(query._conditions, {_id: impressionEvent._id, __t: 'model-discriminator-querying-conversion'});
+                  assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
                   query.exec(function(err, documents) {
                     assert.ifError(err);
                     assert.equal(documents.length, 0);
 
                     // now find one with no criteria given and ensure it gets added to _conditions
                     const query = ConversionEvent.find();
-                    assert.deepEqual(query._conditions, {__t: 'model-discriminator-querying-conversion'});
+                    assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
                     assert.equal(query.op, 'find');
                     query.exec(function(err, documents) {
                       assert.ifError(err);
@@ -255,9 +255,9 @@ describe('model', function() {
       });
 
       const checkDiscriminatorModelsFindDocumentsOfItsType = function(fields, done) {
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent1 = new ConversionEvent({name: 'Conversion event 1', revenue: 1});
-        const conversionEvent2 = new ConversionEvent({name: 'Conversion event 2', revenue: 2});
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent1 = new ConversionEvent({ name: 'Conversion event 1', revenue: 1 });
+        const conversionEvent2 = new ConversionEvent({ name: 'Conversion event 2', revenue: 2 });
 
         impressionEvent.save(function(err) {
           assert.ifError(err);
@@ -266,16 +266,16 @@ describe('model', function() {
             conversionEvent2.save(function(err) {
               assert.ifError(err);
               // doesn't find anything since we're querying for an impression id
-              const query = ConversionEvent.find({_id: impressionEvent._id}, fields);
+              const query = ConversionEvent.find({ _id: impressionEvent._id }, fields);
               assert.equal(query.op, 'find');
-              assert.deepEqual(query._conditions, {_id: impressionEvent._id, __t: 'model-discriminator-querying-conversion'});
+              assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
               query.exec(function(err, documents) {
                 assert.ifError(err);
                 assert.equal(documents.length, 0);
 
                 // now find one with no criteria given and ensure it gets added to _conditions
                 const query = ConversionEvent.find({}, fields);
-                assert.deepEqual(query._conditions, {__t: 'model-discriminator-querying-conversion'});
+                assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
                 assert.equal(query.op, 'find');
                 query.exec(function(err, documents) {
                   assert.ifError(err);
@@ -307,11 +307,11 @@ describe('model', function() {
       });
 
       it('discriminator model only finds documents of its type when fields selection set as object inclusive', function(done) {
-        checkDiscriminatorModelsFindDocumentsOfItsType({name: 1}, done);
+        checkDiscriminatorModelsFindDocumentsOfItsType({ name: 1 }, done);
       });
 
       it('discriminator model only finds documents of its type when fields selection set as object exclusive', function(done) {
-        checkDiscriminatorModelsFindDocumentsOfItsType({revenue: 0}, done);
+        checkDiscriminatorModelsFindDocumentsOfItsType({ revenue: 0 }, done);
       });
 
       it('discriminator model only finds documents of its type when fields selection set as empty object', function(done) {
@@ -365,9 +365,9 @@ describe('model', function() {
       });
 
       it('hydrates correct model', function(done) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -376,20 +376,20 @@ describe('model', function() {
             conversionEvent.save(function(err) {
               assert.ifError(err);
               // finds & hydrates BaseEvent
-              BaseEvent.findOne({_id: baseEvent._id}, function(err, event) {
+              BaseEvent.findOne({ _id: baseEvent._id }, function(err, event) {
                 assert.ifError(err);
                 assert.ok(event instanceof BaseEvent);
                 assert.equal(event.name, 'Base event');
 
                 // finds & hydrates ImpressionEvent
-                BaseEvent.findOne({_id: impressionEvent._id}, function(err, event) {
+                BaseEvent.findOne({ _id: impressionEvent._id }, function(err, event) {
                   assert.ifError(err);
                   assert.ok(event instanceof ImpressionEvent);
                   assert.deepEqual(event.schema.tree, ImpressionEventSchema.tree);
                   assert.equal(event.name, 'Impression event');
 
                   // finds & hydrates ConversionEvent
-                  BaseEvent.findOne({_id: conversionEvent._id}, function(err, event) {
+                  BaseEvent.findOne({ _id: conversionEvent._id }, function(err, event) {
                     assert.ifError(err);
                     assert.ok(event instanceof ConversionEvent);
                     assert.deepEqual(event.schema.tree, ConversionEventSchema.tree);
@@ -404,9 +404,9 @@ describe('model', function() {
       });
 
       const checkHydratesCorrectModels = function(fields, done, checkUndefinedRevenue) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -415,20 +415,20 @@ describe('model', function() {
             conversionEvent.save(function(err) {
               assert.ifError(err);
               // finds & hydrates BaseEvent
-              BaseEvent.findOne({_id: baseEvent._id}, fields, function(err, event) {
+              BaseEvent.findOne({ _id: baseEvent._id }, fields, function(err, event) {
                 assert.ifError(err);
                 assert.ok(event instanceof BaseEvent);
                 assert.equal(event.name, 'Base event');
 
                 // finds & hydrates ImpressionEvent
-                BaseEvent.findOne({_id: impressionEvent._id}, fields, function(err, event) {
+                BaseEvent.findOne({ _id: impressionEvent._id }, fields, function(err, event) {
                   assert.ifError(err);
                   assert.ok(event instanceof ImpressionEvent);
                   assert.deepEqual(event.schema.tree, ImpressionEventSchema.tree);
                   assert.equal(event.name, 'Impression event');
 
                   // finds & hydrates ConversionEvent
-                  BaseEvent.findOne({_id: conversionEvent._id}, fields, function(err, event) {
+                  BaseEvent.findOne({ _id: conversionEvent._id }, fields, function(err, event) {
                     assert.ifError(err);
                     assert.ok(event instanceof ConversionEvent);
                     assert.deepEqual(event.schema.tree, ConversionEventSchema.tree);
@@ -458,11 +458,11 @@ describe('model', function() {
       });
 
       it('hydrates correct model when fields selection set as object inclusive', function(done) {
-        checkHydratesCorrectModels({name: 1}, done, true);
+        checkHydratesCorrectModels({ name: 1 }, done, true);
       });
 
       it('hydrates correct model when fields selection set as object exclusive', function(done) {
-        checkHydratesCorrectModels({revenue: 0}, done, true);
+        checkHydratesCorrectModels({ revenue: 0 }, done, true);
       });
 
       it('hydrates correct model when fields selection set as empty object', function(done) {
@@ -470,17 +470,17 @@ describe('model', function() {
       });
 
       it('discriminator model only finds a document of its type', function(done) {
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 2});
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 2 });
 
         impressionEvent.save(function(err) {
           assert.ifError(err);
           conversionEvent.save(function(err) {
             assert.ifError(err);
             // doesn't find anything since we're querying for an impression id
-            const query = ConversionEvent.findOne({_id: impressionEvent._id});
+            const query = ConversionEvent.findOne({ _id: impressionEvent._id });
             assert.equal(query.op, 'findOne');
-            assert.deepEqual(query._conditions, {_id: impressionEvent._id, __t: 'model-discriminator-querying-conversion'});
+            assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
 
             query.exec(function(err, document) {
               assert.ifError(err);
@@ -489,7 +489,7 @@ describe('model', function() {
               // now find one with no criteria given and ensure it gets added to _conditions
               const query = ConversionEvent.findOne();
               assert.equal(query.op, 'findOne');
-              assert.deepEqual(query._conditions, {__t: 'model-discriminator-querying-conversion'});
+              assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
 
               query.exec(function(err, document) {
                 assert.ifError(err);
@@ -503,17 +503,17 @@ describe('model', function() {
       });
 
       const checkDiscriminatorModelsFindOneDocumentOfItsType = function(fields, done) {
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 2});
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 2 });
 
         impressionEvent.save(function(err) {
           assert.ifError(err);
           conversionEvent.save(function(err) {
             assert.ifError(err);
             // doesn't find anything since we're querying for an impression id
-            const query = ConversionEvent.findOne({_id: impressionEvent._id}, fields);
+            const query = ConversionEvent.findOne({ _id: impressionEvent._id }, fields);
             assert.equal(query.op, 'findOne');
-            assert.deepEqual(query._conditions, {_id: impressionEvent._id, __t: 'model-discriminator-querying-conversion'});
+            assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
 
             query.exec(function(err, document) {
               assert.ifError(err);
@@ -522,7 +522,7 @@ describe('model', function() {
               // now find one with no criteria given and ensure it gets added to _conditions
               const query = ConversionEvent.findOne({}, fields);
               assert.equal(query.op, 'findOne');
-              assert.deepEqual(query._conditions, {__t: 'model-discriminator-querying-conversion'});
+              assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
 
               query.exec(function(err, document) {
                 assert.ifError(err);
@@ -548,11 +548,11 @@ describe('model', function() {
       });
 
       it('discriminator model only finds a document of its type when fields selection set as object inclusive', function(done) {
-        checkDiscriminatorModelsFindOneDocumentOfItsType({name: 1}, done);
+        checkDiscriminatorModelsFindOneDocumentOfItsType({ name: 1 }, done);
       });
 
       it('discriminator model only finds a document of its type when fields selection set as object exclusive', function(done) {
-        checkDiscriminatorModelsFindOneDocumentOfItsType({revenue: 0}, done);
+        checkDiscriminatorModelsFindOneDocumentOfItsType({ revenue: 0 }, done);
       });
 
       it('discriminator model only finds a document of its type when fields selection set as empty object', function(done) {
@@ -562,9 +562,9 @@ describe('model', function() {
 
     describe('findOneAndUpdate', function() {
       it('does not update models of other types', function(done) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -572,8 +572,8 @@ describe('model', function() {
             assert.ifError(err);
             conversionEvent.save(function(err) {
               assert.ifError(err);
-              const query = ConversionEvent.findOneAndUpdate({name: 'Impression event'}, {$set: {name: 'Impression event - updated'}});
-              assert.deepEqual(query._conditions, {name: 'Impression event', __t: 'model-discriminator-querying-conversion'});
+              const query = ConversionEvent.findOneAndUpdate({ name: 'Impression event' }, { $set: { name: 'Impression event - updated' } });
+              assert.deepEqual(query._conditions, { name: 'Impression event', __t: 'model-discriminator-querying-conversion' });
               query.exec(function(err, document) {
                 assert.ifError(err);
                 assert.equal(document, null);
@@ -585,9 +585,9 @@ describe('model', function() {
       });
 
       it('updates models of its own type', function(done) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -595,8 +595,8 @@ describe('model', function() {
             assert.ifError(err);
             conversionEvent.save(function(err) {
               assert.ifError(err);
-              const query = ConversionEvent.findOneAndUpdate({name: 'Conversion event'}, {$set: {name: 'Conversion event - updated'}}, {new: true});
-              assert.deepEqual(query._conditions, {name: 'Conversion event', __t: 'model-discriminator-querying-conversion'});
+              const query = ConversionEvent.findOneAndUpdate({ name: 'Conversion event' }, { $set: { name: 'Conversion event - updated' } }, { new: true });
+              assert.deepEqual(query._conditions, { name: 'Conversion event', __t: 'model-discriminator-querying-conversion' });
               query.exec(function(err, document) {
                 assert.ifError(err);
                 const expected = conversionEvent.toJSON();
@@ -610,9 +610,9 @@ describe('model', function() {
       });
 
       it('base model modifies any event type', function(done) {
-        const baseEvent = new BaseEvent({name: 'Base event'});
-        const impressionEvent = new ImpressionEvent({name: 'Impression event'});
-        const conversionEvent = new ConversionEvent({name: 'Conversion event', revenue: 1.337});
+        const baseEvent = new BaseEvent({ name: 'Base event' });
+        const impressionEvent = new ImpressionEvent({ name: 'Impression event' });
+        const conversionEvent = new ConversionEvent({ name: 'Conversion event', revenue: 1.337 });
 
         baseEvent.save(function(err) {
           assert.ifError(err);
@@ -620,8 +620,8 @@ describe('model', function() {
             assert.ifError(err);
             conversionEvent.save(function(err) {
               assert.ifError(err);
-              const query = BaseEvent.findOneAndUpdate({name: 'Conversion event'}, {$set: {name: 'Conversion event - updated'}}, {new: true});
-              assert.deepEqual(query._conditions, {name: 'Conversion event'});
+              const query = BaseEvent.findOneAndUpdate({ name: 'Conversion event' }, { $set: { name: 'Conversion event - updated' } }, { new: true });
+              assert.deepEqual(query._conditions, { name: 'Conversion event' });
               query.exec(function(err, document) {
                 assert.ifError(err);
                 const expected = conversionEvent.toJSON();
@@ -638,13 +638,13 @@ describe('model', function() {
     describe('population/reference mapping', function() {
       it('populates and hydrates correct models', function(done) {
         const vehicleSchema = new Schema();
-        const carSchema = new Schema({speed: Number});
-        const busSchema = new Schema({speed: Number});
+        const carSchema = new Schema({ speed: Number });
+        const busSchema = new Schema({ speed: Number });
 
         const userSchema = new Schema({
-          vehicles: [{type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationVehicle'}],
-          favoriteVehicle: {type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationVehicle'},
-          favoriteBus: {type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationBus'}
+          vehicles: [{ type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationVehicle' }],
+          favoriteVehicle: { type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationVehicle' },
+          favoriteBus: { type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationBus' }
         });
 
         const Vehicle = db.model('ModelDiscriminatorPopulationVehicle', vehicleSchema);
@@ -654,10 +654,10 @@ describe('model', function() {
 
         Vehicle.create({}, function(err, vehicle) {
           assert.ifError(err);
-          Car.create({speed: 160}, function(err, car) {
-            Bus.create({speed: 80}, function(err, bus) {
+          Car.create({ speed: 160 }, function(err, car) {
+            Bus.create({ speed: 80 }, function(err, bus) {
               assert.ifError(err);
-              User.create({vehicles: [vehicle._id, car._id, bus._id], favoriteVehicle: car._id, favoriteBus: bus._id}, function(err) {
+              User.create({ vehicles: [vehicle._id, car._id, bus._id], favoriteVehicle: car._id, favoriteBus: bus._id }, function(err) {
                 assert.ifError(err);
                 User.findOne({}).populate('vehicles favoriteVehicle favoriteBus').exec(function(err, user) {
                   assert.ifError(err);
@@ -666,12 +666,12 @@ describe('model', function() {
                     __v: 0,
                     _id: user._id,
                     vehicles: [
-                      {_id: vehicle._id, __v: 0},
-                      {_id: car._id, speed: 160, __v: 0, __t: 'ModelDiscriminatorPopulationCar'},
-                      {_id: bus._id, speed: 80, __v: 0, __t: 'ModelDiscriminatorPopulationBus'}
+                      { _id: vehicle._id, __v: 0 },
+                      { _id: car._id, speed: 160, __v: 0, __t: 'ModelDiscriminatorPopulationCar' },
+                      { _id: bus._id, speed: 80, __v: 0, __t: 'ModelDiscriminatorPopulationBus' }
                     ],
-                    favoriteVehicle: {_id: car._id, speed: 160, __v: 0, __t: 'ModelDiscriminatorPopulationCar'},
-                    favoriteBus: {_id: bus._id, speed: 80, __v: 0, __t: 'ModelDiscriminatorPopulationBus'}
+                    favoriteVehicle: { _id: car._id, speed: 160, __v: 0, __t: 'ModelDiscriminatorPopulationCar' },
+                    favoriteBus: { _id: bus._id, speed: 80, __v: 0, __t: 'ModelDiscriminatorPopulationBus' }
                   };
 
                   assert.deepEqual(user.toJSON(), expected);
@@ -699,11 +699,11 @@ describe('model', function() {
         const vehicleSchema = new Schema({});
         const carSchema = new Schema({
           speed: Number,
-          garage: {type: Schema.Types.ObjectId, ref: 'gh2719PopulationGarage'}
+          garage: { type: Schema.Types.ObjectId, ref: 'gh2719PopulationGarage' }
         });
         const busSchema = new Schema({
           speed: Number,
-          garage: {type: Schema.Types.ObjectId, ref: 'gh2719PopulationGarage'}
+          garage: { type: Schema.Types.ObjectId, ref: 'gh2719PopulationGarage' }
         });
 
         const garageSchema = new Schema({
@@ -716,11 +716,11 @@ describe('model', function() {
         const Bus = Vehicle.discriminator('gh2719PopulationBus', busSchema);
         const Garage = db.model('gh2719PopulationGarage', garageSchema);
 
-        Garage.create({name: 'My', num_of_places: 3}, function(err, garage) {
+        Garage.create({ name: 'My', num_of_places: 3 }, function(err, garage) {
           assert.ifError(err);
-          Car.create({speed: 160, garage: garage}, function(err) {
+          Car.create({ speed: 160, garage: garage }, function(err) {
             assert.ifError(err);
-            Bus.create({speed: 80, garage: garage}, function(err) {
+            Bus.create({ speed: 80, garage: garage }, function(err) {
               assert.ifError(err);
               Vehicle.find({}).populate('garage').exec(function(err, vehicles) {
                 assert.ifError(err);
@@ -773,7 +773,7 @@ describe('model', function() {
           Schema.apply(this, arguments);
 
           this.add({
-            name: {type: String, required: true}
+            name: { type: String, required: true }
           });
         }
 
@@ -801,10 +801,10 @@ describe('model', function() {
           Schema.apply(this, arguments);
 
           this.add({
-            name: {type: String, required: true},
-            date: {type: Date, required: true},
-            period: {start: {type: String, required: true},
-              end: {type: String, required: true}
+            name: { type: String, required: true },
+            date: { type: Date, required: true },
+            period: { start: { type: String, required: true },
+              end: { type: String, required: true }
             }
           });
         }
@@ -815,11 +815,11 @@ describe('model', function() {
         const Event = db.model('Event', EventSchema);
 
         const TalkSchema = new BaseSchema({
-          pin: {type: String, required: true, index: {unique: true}},
-          totalAttendees: {type: Number},
-          speakers: [{type: Schema.Types.ObjectId, ref: 'Speaker'}],
-          surveys: [{type: Schema.Types.ObjectId, ref: 'Survey'}],
-          questions: [{type: Schema.Types.ObjectId, ref: 'Question'}]
+          pin: { type: String, required: true, index: { unique: true } },
+          totalAttendees: { type: Number },
+          speakers: [{ type: Schema.Types.ObjectId, ref: 'Speaker' }],
+          surveys: [{ type: Schema.Types.ObjectId, ref: 'Survey' }],
+          questions: [{ type: Schema.Types.ObjectId, ref: 'Question' }]
         });
 
         const Talk = Event.discriminator('Talk', TalkSchema);
@@ -839,7 +839,7 @@ describe('model', function() {
             name: 'Meetup rails',
             date: new Date('2015-04-01T00:00:00Z'),
             pin: '0004',
-            period: {start: '11:00', end: '12:00'},
+            period: { start: '11:00', end: '12:00' },
             surveys: [survey]
           }, function(err) {
             assert.ifError(err);
@@ -920,9 +920,9 @@ describe('model', function() {
       let impressionEvent, conversionEvent, ignoredImpressionEvent;
 
       beforeEach(function() {
-        impressionEvent = new ImpressionEvent({name: 'Test Event'});
-        conversionEvent = new ConversionEvent({name: 'Test Event', revenue: 10});
-        ignoredImpressionEvent = new ImpressionEvent({name: 'Ignored Event'});
+        impressionEvent = new ImpressionEvent({ name: 'Test Event' });
+        conversionEvent = new ConversionEvent({ name: 'Test Event', revenue: 10 });
+        ignoredImpressionEvent = new ImpressionEvent({ name: 'Ignored Event' });
 
         return Promise.all([impressionEvent, conversionEvent, ignoredImpressionEvent].map(d => d.save()));
       });
@@ -930,13 +930,13 @@ describe('model', function() {
       describe('using "RootModel#aggregate"', function() {
         it('to aggregate documents of all discriminators', function(done) {
           const aggregate = BaseEvent.aggregate([
-            {$match: {name: 'Test Event'}}
+            { $match: { name: 'Test Event' } }
           ]);
 
           aggregate.exec(function(err, docs) {
             assert.ifError(err);
             assert.deepEqual(aggregate._pipeline, [
-              {$match: {name: 'Test Event'}}
+              { $match: { name: 'Test Event' } }
             ]);
             assert.equal(docs.length, 2);
             done();
@@ -947,7 +947,7 @@ describe('model', function() {
       describe('using "ModelDiscriminator#aggregate"', function() {
         it('only aggregates documents of the appropriate discriminator', function(done) {
           const aggregate = ImpressionEvent.aggregate([
-            {$group: {_id: '$__t', count: {$sum: 1}}}
+            { $group: { _id: '$__t', count: { $sum: 1 } } }
           ]);
 
           aggregate.exec(function(err, result) {
@@ -958,13 +958,13 @@ describe('model', function() {
             // aggregations with empty pipelines, but that are over
             // discriminators be executed
             assert.deepEqual(aggregate._pipeline, [
-              {$match: {__t: 'model-discriminator-querying-impression'}},
-              {$group: {_id: '$__t', count: {$sum: 1}}}
+              { $match: { __t: 'model-discriminator-querying-impression' } },
+              { $group: { _id: '$__t', count: { $sum: 1 } } }
             ]);
 
             assert.equal(result.length, 1);
             assert.deepEqual(result, [
-              {_id: 'model-discriminator-querying-impression', count: 2}
+              { _id: 'model-discriminator-querying-impression', count: 2 }
             ]);
             done();
           });
@@ -1004,12 +1004,12 @@ describe('model', function() {
         it('doesnt exclude field if slice (gh-4991)', function(done) {
           const baseSchema = new mongoose.Schema({
             propA: { type: String, default: 'default value' },
-            array: [{type: String}]
+            array: [{ type: String }]
           });
 
           const Base = db.model('gh4991_A', baseSchema);
           const discriminatorSchema = new mongoose.Schema({
-            propB: { type: String}
+            propB: { type: String }
           });
           const Discriminator = Base.discriminator('gh4991_A1', discriminatorSchema);
 
@@ -1026,7 +1026,7 @@ describe('model', function() {
 
         it('merges the first pipeline stages if applicable', function(done) {
           const aggregate = ImpressionEvent.aggregate([
-            {$match: {name: 'Test Event'}}
+            { $match: { name: 'Test Event' } }
           ]);
 
           aggregate.exec(function(err, result) {
@@ -1037,7 +1037,7 @@ describe('model', function() {
             // aggregations with empty pipelines, but that are over
             // discriminators be executed
             assert.deepEqual(aggregate._pipeline, [
-              {$match: {__t: 'model-discriminator-querying-impression', name: 'Test Event'}}
+              { $match: { __t: 'model-discriminator-querying-impression', name: 'Test Event' } }
             ]);
 
             assert.equal(result.length, 1);
diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index d2e2d454436..104d80ac3aa 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -48,7 +48,7 @@ describe('model field selection', function() {
       sigs: [Buffer],
       owners: [ObjectId],
       comments: [Comments],
-      def: {type: String, default: 'kandinsky'}
+      def: { type: String, default: 'kandinsky' }
     });
 
     modelName = 'model.select.blogpost';
@@ -68,15 +68,15 @@ describe('model field selection', function() {
     const doc = {
       title: 'subset 1',
       author: 'me',
-      comments: [{title: 'first comment', date: new Date}, {title: '2nd', date: new Date}],
-      meta: {date: date}
+      comments: [{ title: 'first comment', date: new Date }, { title: '2nd', date: new Date }],
+      meta: { date: date }
     };
 
     BlogPostB.create(doc, function(err, created) {
       assert.ifError(err);
 
       const id = created.id;
-      BlogPostB.findById(id, {title: 0, 'meta.date': 0, owners: 0, 'comments.user': 0}, function(err, found) {
+      BlogPostB.findById(id, { title: 0, 'meta.date': 0, owners: 0, 'comments.user': 0 }, function(err, found) {
         assert.ifError(err);
         assert.equal(found._id.toString(), created._id);
         assert.strictEqual(undefined, found.title);
@@ -101,10 +101,10 @@ describe('model field selection', function() {
     const id = new DocumentObjectId;
     const date = new Date;
 
-    BlogPostB.collection.insertOne({_id: id, title: 'hahaha1', meta: {date: date}}, function(err) {
+    BlogPostB.collection.insertOne({ _id: id, title: 'hahaha1', meta: { date: date } }, function(err) {
       assert.ifError(err);
 
-      BlogPostB.findById(id, {title: 0}, function(err, found) {
+      BlogPostB.findById(id, { title: 0 }, function(err, found) {
         assert.ifError(err);
         assert.equal(found._id.toString(), id);
         assert.strictEqual(undefined, found.title);
@@ -120,9 +120,9 @@ describe('model field selection', function() {
 
   it('where subset of fields excludes _id', function(done) {
     const BlogPostB = db.model(modelName, collection);
-    BlogPostB.create({title: 'subset 1'}, function(err) {
+    BlogPostB.create({ title: 'subset 1' }, function(err) {
       assert.ifError(err);
-      BlogPostB.findOne({title: 'subset 1'}, {title: 1, _id: 0}, function(err, found) {
+      BlogPostB.findOne({ title: 'subset 1' }, { title: 1, _id: 0 }, function(err, found) {
         assert.ifError(err);
         assert.strictEqual(undefined, found._id);
         assert.equal(found.title, 'subset 1');
@@ -133,9 +133,9 @@ describe('model field selection', function() {
 
   it('works with subset of fields, excluding _id', function(done) {
     const BlogPostB = db.model(modelName, collection);
-    BlogPostB.create({title: 'subset 1', author: 'me'}, function(err) {
+    BlogPostB.create({ title: 'subset 1', author: 'me' }, function(err) {
       assert.ifError(err);
-      BlogPostB.find({title: 'subset 1'}, {title: 1, _id: 0}, function(err, found) {
+      BlogPostB.find({ title: 'subset 1' }, { title: 1, _id: 0 }, function(err, found) {
         assert.ifError(err);
         assert.strictEqual(undefined, found[0]._id);
         assert.equal(found[0].title, 'subset 1');
@@ -148,11 +148,11 @@ describe('model field selection', function() {
   });
 
   it('works with just _id and findOneAndUpdate (gh-3407)', function(done) {
-    const MyModel = db.model('gh3407', {test: {type: Number, default: 1}});
+    const MyModel = db.model('gh3407', { test: { type: Number, default: 1 } });
 
     MyModel.collection.insertOne({}, function(error) {
       assert.ifError(error);
-      MyModel.findOne({}, {_id: 1}, function(error, doc) {
+      MyModel.findOne({}, { _id: 1 }, function(error, doc) {
         assert.ifError(error);
         assert.ok(!doc.test);
         done();
@@ -163,9 +163,9 @@ describe('model field selection', function() {
   it('works with subset of fields excluding emebedded doc _id (gh-541)', function(done) {
     const BlogPostB = db.model(modelName, collection);
 
-    BlogPostB.create({title: 'LOTR', comments: [{title: ':)'}]}, function(err, created) {
+    BlogPostB.create({ title: 'LOTR', comments: [{ title: ':)' }] }, function(err, created) {
       assert.ifError(err);
-      BlogPostB.find({_id: created}, {_id: 0, 'comments._id': 0}, function(err, found) {
+      BlogPostB.find({ _id: created }, { _id: 0, 'comments._id': 0 }, function(err, found) {
         assert.ifError(err);
         assert.strictEqual(undefined, found[0]._id);
         assert.equal(found[0].title, 'LOTR');
@@ -187,7 +187,7 @@ describe('model field selection', function() {
     const id = new DocumentObjectId;
 
     BlogPostB.collection.insertOne(
-      {_id: id, title: 'issue 870'}, {safe: true}, function(err) {
+      { _id: id, title: 'issue 870' }, { safe: true }, function(err) {
         assert.ifError(err);
 
         BlogPostB.findById(id, 'def comments', function(err, found) {
@@ -207,7 +207,7 @@ describe('model field selection', function() {
   it('including subdoc field excludes other subdoc fields (gh-1027)', function(done) {
     const BlogPostB = db.model(modelName, collection);
 
-    BlogPostB.create({comments: [{title: 'a'}, {title: 'b'}]}, function(err, doc) {
+    BlogPostB.create({ comments: [{ title: 'a' }, { title: 'b' }] }, function(err, doc) {
       assert.ifError(err);
 
       BlogPostB.findById(doc._id).select('_id comments.title').exec(function(err, found) {
@@ -230,7 +230,7 @@ describe('model field selection', function() {
   it('excluding nested subdoc fields (gh-1027)', function(done) {
     const BlogPostB = db.model(modelName, collection);
 
-    BlogPostB.create({title: 'top', comments: [{title: 'a', body: 'body'}, {title: 'b', body: 'body', comments: [{title: 'c'}]}]}, function(err, doc) {
+    BlogPostB.create({ title: 'top', comments: [{ title: 'a', body: 'body' }, { title: 'b', body: 'body', comments: [{ title: 'c' }] }] }, function(err, doc) {
       assert.ifError(err);
 
       BlogPostB.findById(doc._id).select('-_id -comments.title -comments.comments.comments -numbers').exec(function(err, found) {
@@ -262,19 +262,19 @@ describe('model field selection', function() {
 
     it('casts elemMatch args (gh-1091)', function(done) {
       const postSchema = new Schema({
-        ids: [{type: Schema.ObjectId}]
+        ids: [{ type: Schema.ObjectId }]
       });
 
       const B = db.model('gh-1091', postSchema);
       const _id1 = new mongoose.Types.ObjectId;
       const _id2 = new mongoose.Types.ObjectId;
 
-      B.create({ids: [_id1, _id2]}, function(err, doc) {
+      B.create({ ids: [_id1, _id2] }, function(err, doc) {
         assert.ifError(err);
 
         B
           .findById(doc._id)
-          .select({ids: {$elemMatch: {$in: [_id2.toString()]}}})
+          .select({ ids: { $elemMatch: { $in: [_id2.toString()] } } })
           .exec(function(err, found) {
             assert.ifError(err);
             assert.ok(found);
@@ -283,8 +283,8 @@ describe('model field selection', function() {
             assert.equal(found.ids[0].toString(), _id2.toString());
 
             B
-              .find({_id: doc._id})
-              .select({ids: {$elemMatch: {$in: [_id2.toString()]}}})
+              .find({ _id: doc._id })
+              .select({ ids: { $elemMatch: { $in: [_id2.toString()] } } })
               .exec(function(err, found) {
                 assert.ifError(err);
                 assert.ok(found.length);
@@ -300,20 +300,20 @@ describe('model field selection', function() {
 
     it('saves modified elemMatch paths (gh-1334)', function(done) {
       const postSchema = new Schema({
-        ids: [{type: Schema.ObjectId}],
-        ids2: [{type: Schema.ObjectId}]
+        ids: [{ type: Schema.ObjectId }],
+        ids2: [{ type: Schema.ObjectId }]
       });
 
       const B = db.model('gh-1334', postSchema);
       const _id1 = new mongoose.Types.ObjectId;
       const _id2 = new mongoose.Types.ObjectId;
 
-      B.create({ids: [_id1, _id2], ids2: [_id2, _id1]}, function(err, doc) {
+      B.create({ ids: [_id1, _id2], ids2: [_id2, _id1] }, function(err, doc) {
         assert.ifError(err);
 
         B
           .findById(doc._id)
-          .select({ids2: {$elemMatch: {$in: [_id1.toString()]}}})
+          .select({ ids2: { $elemMatch: { $in: [_id1.toString()] } } })
           .exec(function(err, found) {
             assert.ifError(err);
             assert.equal(found.ids2.length, 1);
@@ -324,7 +324,7 @@ describe('model field selection', function() {
 
               B
                 .findById(doc._id)
-                .select({ids: {$elemMatch: {$in: [_id2.toString()]}}})
+                .select({ ids: { $elemMatch: { $in: [_id2.toString()] } } })
                 .select('ids2')
                 .exec(function(err, found) {
                   assert.equal(2, found.ids2.length);
@@ -346,13 +346,13 @@ describe('model field selection', function() {
 
     it('works with $ positional in select (gh-2031)', function(done) {
       const postSchema = new Schema({
-        tags: [{tag: String, count: 0}]
+        tags: [{ tag: String, count: 0 }]
       });
 
       const Post = db.model('gh-2031', postSchema, 'gh-2031');
-      Post.create({tags: [{tag: 'bacon', count: 2}, {tag: 'eggs', count: 3}]}, function(error) {
+      Post.create({ tags: [{ tag: 'bacon', count: 2 }, { tag: 'eggs', count: 3 }] }, function(error) {
         assert.ifError(error);
-        Post.findOne({'tags.tag': 'eggs'}, {'tags.$': 1}, function(error, post) {
+        Post.findOne({ 'tags.tag': 'eggs' }, { 'tags.$': 1 }, function(error, post) {
           assert.ifError(error);
           post.tags[0].count = 1;
           post.save(function(error) {
@@ -367,7 +367,7 @@ describe('model field selection', function() {
   it('selecting an array of docs applies defaults properly (gh-1108)', function(done) {
     const M = db.model(modelName, collection);
 
-    const m = new M({title: '1108', comments: [{body: 'yay'}]});
+    const m = new M({ title: '1108', comments: [{ body: 'yay' }] });
     m.comments[0].comments = undefined;
     m.save(function(err, doc) {
       assert.ifError(err);
@@ -403,17 +403,17 @@ describe('model field selection', function() {
     const RouteSchema = new Schema({
       stations: {
         start: {
-          name: {type: String},
-          loc: {type: [Number], index: '2d'}
+          name: { type: String },
+          loc: { type: [Number], index: '2d' }
         },
         end: {
-          name: {type: String},
-          loc: {type: [Number], index: '2d'}
+          name: { type: String },
+          loc: { type: [Number], index: '2d' }
         },
         points: [
           {
-            name: {type: String},
-            loc: {type: [Number], index: '2d'}
+            name: { type: String },
+            loc: { type: [Number], index: '2d' }
           }
         ]
       }
@@ -431,7 +431,7 @@ describe('model field selection', function() {
           name: 'thingend',
           loc: [2, 3]
         },
-        points: [{name: 'rawr'}]
+        points: [{ name: 'rawr' }]
       }
     };
 
diff --git a/test/model.findOneAndDelete.test.js b/test/model.findOneAndDelete.test.js
index 4c6e80f789d..046fefcac70 100644
--- a/test/model.findOneAndDelete.test.js
+++ b/test/model.findOneAndDelete.test.js
@@ -72,7 +72,7 @@ describe('model: findOneAndDelete:', function() {
 
     collection = 'deleteoneblogposts';
 
-    strictSchema = new Schema({name: String}, {strict: true});
+    strictSchema = new Schema({ name: String }, { strict: true });
     mongoose.model('DeleteOneStrictSchema', strictSchema);
 
     db = start();
@@ -86,12 +86,12 @@ describe('model: findOneAndDelete:', function() {
     const M = db.model(modelname, collection);
     const title = 'remove muah';
 
-    const post = new M({title: title});
+    const post = new M({ title: title });
 
     return co(function*() {
       yield post.save();
 
-      const doc = yield M.findOneAndDelete({title: title});
+      const doc = yield M.findOneAndDelete({ title: title });
 
       assert.equal(post.id, doc.id);
 
@@ -107,11 +107,11 @@ describe('model: findOneAndDelete:', function() {
     let query;
 
     // Model.findOneAndDelete
-    query = M.findOneAndDelete({author: 'aaron'}, {select: 'author'});
+    query = M.findOneAndDelete({ author: 'aaron' }, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions.author, 'aaron');
 
-    query = M.findOneAndDelete({author: 'aaron'});
+    query = M.findOneAndDelete({ author: 'aaron' });
     assert.equal(query._fields, undefined);
     assert.equal(query._conditions.author, 'aaron');
 
@@ -121,12 +121,12 @@ describe('model: findOneAndDelete:', function() {
     assert.equal(query._conditions.author, undefined);
 
     // Query.findOneAndDelete
-    query = M.where('author', 'aaron').findOneAndDelete({date: now});
+    query = M.where('author', 'aaron').findOneAndDelete({ date: now });
     assert.equal(query._fields, undefined);
     assert.equal(query._conditions.date, now);
     assert.equal(query._conditions.author, 'aaron');
 
-    query = M.find().findOneAndDelete({author: 'aaron'}, {select: 'author'});
+    query = M.find().findOneAndDelete({ author: 'aaron' }, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions.author, 'aaron');
 
@@ -140,10 +140,10 @@ describe('model: findOneAndDelete:', function() {
     const M = db.model(modelname, collection + random());
     let pending = 5;
 
-    M.findOneAndDelete({name: 'aaron1'}, {select: 'name'}, cb);
-    M.findOneAndDelete({name: 'aaron1'}, cb);
-    M.where().findOneAndDelete({name: 'aaron1'}, {select: 'name'}, cb);
-    M.where().findOneAndDelete({name: 'aaron1'}, cb);
+    M.findOneAndDelete({ name: 'aaron1' }, { select: 'name' }, cb);
+    M.findOneAndDelete({ name: 'aaron1' }, cb);
+    M.where().findOneAndDelete({ name: 'aaron1' }, { select: 'name' }, cb);
+    M.where().findOneAndDelete({ name: 'aaron1' }, cb);
     M.where('name', 'aaron1').findOneAndDelete(cb);
 
     function cb(err, doc) {
@@ -187,7 +187,7 @@ describe('model: findOneAndDelete:', function() {
     const _id = new DocumentObjectId;
     let pending = 2;
 
-    M.findByIdAndDelete(_id, {select: 'name'}, cb);
+    M.findByIdAndDelete(_id, { select: 'name' }, cb);
     M.findByIdAndDelete(_id, cb);
 
     function cb(err, doc) {
@@ -202,7 +202,7 @@ describe('model: findOneAndDelete:', function() {
     const M = db.model(modelname, collection);
     const title = 'remove muah pleez';
 
-    const post = new M({title: title});
+    const post = new M({ title: title });
     post.save(function(err) {
       assert.ifError(err);
       M.findByIdAndDelete(post.id, function(err, doc) {
@@ -224,7 +224,7 @@ describe('model: findOneAndDelete:', function() {
     let query;
 
     // Model.findByIdAndDelete
-    query = M.findByIdAndDelete(_id, {select: 'author'});
+    query = M.findByIdAndDelete(_id, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions._id.toString(), _id.toString());
 
@@ -245,11 +245,11 @@ describe('model: findOneAndDelete:', function() {
 
     let query;
 
-    query = M.findByIdAndDelete(_id, {select: 'author -title'});
+    query = M.findByIdAndDelete(_id, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
 
-    query = M.findOneAndDelete({}, {select: 'author -title'});
+    query = M.findOneAndDelete({}, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -261,11 +261,11 @@ describe('model: findOneAndDelete:', function() {
 
     let query;
 
-    query = M.findByIdAndDelete(_id, {select: {author: 1, title: 0}});
+    query = M.findByIdAndDelete(_id, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
 
-    query = M.findOneAndDelete({}, {select: {author: 1, title: 0}});
+    query = M.findOneAndDelete({}, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -277,12 +277,12 @@ describe('model: findOneAndDelete:', function() {
 
     let query;
 
-    query = M.findByIdAndDelete(_id, {sort: 'author -title'});
+    query = M.findByIdAndDelete(_id, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
-    query = M.findOneAndDelete({}, {sort: 'author -title'});
+    query = M.findOneAndDelete({}, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -295,12 +295,12 @@ describe('model: findOneAndDelete:', function() {
 
     let query;
 
-    query = M.findByIdAndDelete(_id, {sort: {author: 1, title: -1}});
+    query = M.findByIdAndDelete(_id, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
-    query = M.findOneAndDelete(_id, {sort: {author: 1, title: -1}});
+    query = M.findOneAndDelete(_id, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -308,15 +308,15 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', {name: String});
-    const N = db.model('B', {a: {type: Schema.ObjectId, ref: 'A'}, i: Number});
+    const M = db.model('A', { name: String });
+    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
 
-    M.create({name: 'i am an A'}, function(err, a) {
+    M.create({ name: 'i am an A' }, function(err, a) {
       if (err) return done(err);
-      N.create({a: a._id, i: 10}, function(err, b) {
+      N.create({ a: a._id, i: 10 }, function(err, b) {
         if (err) return done(err);
 
-        N.findOneAndDelete({_id: b._id}, {select: 'a -_id'})
+        N.findOneAndDelete({ _id: b._id }, { select: 'a -_id' })
           .populate('a')
           .exec(function(err, doc) {
             if (err) return done(err);
@@ -354,7 +354,7 @@ describe('model: findOneAndDelete:', function() {
   describe('middleware', function() {
     it('works', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -377,7 +377,7 @@ describe('model: findOneAndDelete:', function() {
         assert.ifError(error);
 
         Breakfast.findOneAndDelete(
-          {base: 'eggs'},
+          { base: 'eggs' },
           {},
           function(error, breakfast) {
             assert.ifError(error);
@@ -391,7 +391,7 @@ describe('model: findOneAndDelete:', function() {
 
     it('works with exec() (gh-439)', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -414,7 +414,7 @@ describe('model: findOneAndDelete:', function() {
         assert.ifError(error);
 
         Breakfast.
-          findOneAndDelete({base: 'eggs'}, {}).
+          findOneAndDelete({ base: 'eggs' }, {}).
           exec(function(error, breakfast) {
             assert.ifError(error);
             assert.equal(breakfast.base, 'eggs');
diff --git a/test/model.findOneAndRemove.test.js b/test/model.findOneAndRemove.test.js
index 901e9e05885..e8dd6d4c01f 100644
--- a/test/model.findOneAndRemove.test.js
+++ b/test/model.findOneAndRemove.test.js
@@ -72,7 +72,7 @@ describe('model: findOneAndRemove:', function() {
 
     collection = 'removeoneblogposts_' + random();
 
-    strictSchema = new Schema({name: String}, {strict: true});
+    strictSchema = new Schema({ name: String }, { strict: true });
     mongoose.model('RemoveOneStrictSchema', strictSchema);
 
     db = start();
@@ -86,12 +86,12 @@ describe('model: findOneAndRemove:', function() {
     const M = db.model(modelname, collection);
     const title = 'remove muah';
 
-    const post = new M({title: title});
+    const post = new M({ title: title });
 
     return co(function*() {
       yield post.save();
 
-      const doc = yield M.findOneAndRemove({title: title});
+      const doc = yield M.findOneAndRemove({ title: title });
 
       assert.equal(post.id, doc.id);
 
@@ -107,11 +107,11 @@ describe('model: findOneAndRemove:', function() {
     let query;
 
     // Model.findOneAndRemove
-    query = M.findOneAndRemove({author: 'aaron'}, {select: 'author'});
+    query = M.findOneAndRemove({ author: 'aaron' }, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions.author, 'aaron');
 
-    query = M.findOneAndRemove({author: 'aaron'});
+    query = M.findOneAndRemove({ author: 'aaron' });
     assert.equal(query._fields, undefined);
     assert.equal(query._conditions.author, 'aaron');
 
@@ -121,12 +121,12 @@ describe('model: findOneAndRemove:', function() {
     assert.equal(query._conditions.author, undefined);
 
     // Query.findOneAndRemove
-    query = M.where('author', 'aaron').findOneAndRemove({date: now});
+    query = M.where('author', 'aaron').findOneAndRemove({ date: now });
     assert.equal(query._fields, undefined);
     assert.equal(query._conditions.date, now);
     assert.equal(query._conditions.author, 'aaron');
 
-    query = M.find().findOneAndRemove({author: 'aaron'}, {select: 'author'});
+    query = M.find().findOneAndRemove({ author: 'aaron' }, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions.author, 'aaron');
 
@@ -140,10 +140,10 @@ describe('model: findOneAndRemove:', function() {
     const M = db.model(modelname, collection + random());
     let pending = 5;
 
-    M.findOneAndRemove({name: 'aaron1'}, {select: 'name'}, cb);
-    M.findOneAndRemove({name: 'aaron1'}, cb);
-    M.where().findOneAndRemove({name: 'aaron1'}, {select: 'name'}, cb);
-    M.where().findOneAndRemove({name: 'aaron1'}, cb);
+    M.findOneAndRemove({ name: 'aaron1' }, { select: 'name' }, cb);
+    M.findOneAndRemove({ name: 'aaron1' }, cb);
+    M.where().findOneAndRemove({ name: 'aaron1' }, { select: 'name' }, cb);
+    M.where().findOneAndRemove({ name: 'aaron1' }, cb);
     M.where('name', 'aaron1').findOneAndRemove(cb);
 
     function cb(err, doc) {
@@ -187,7 +187,7 @@ describe('model: findOneAndRemove:', function() {
     const _id = new DocumentObjectId;
     let pending = 2;
 
-    M.findByIdAndRemove(_id, {select: 'name'}, cb);
+    M.findByIdAndRemove(_id, { select: 'name' }, cb);
     M.findByIdAndRemove(_id, cb);
 
     function cb(err, doc) {
@@ -202,7 +202,7 @@ describe('model: findOneAndRemove:', function() {
     const M = db.model(modelname, collection);
     const title = 'remove muah pleez';
 
-    const post = new M({title: title});
+    const post = new M({ title: title });
     post.save(function(err) {
       assert.ifError(err);
       M.findByIdAndRemove(post.id, function(err, doc) {
@@ -224,7 +224,7 @@ describe('model: findOneAndRemove:', function() {
     let query;
 
     // Model.findByIdAndRemove
-    query = M.findByIdAndRemove(_id, {select: 'author'});
+    query = M.findByIdAndRemove(_id, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions._id.toString(), _id.toString());
 
@@ -245,11 +245,11 @@ describe('model: findOneAndRemove:', function() {
 
     let query;
 
-    query = M.findByIdAndRemove(_id, {select: 'author -title'});
+    query = M.findByIdAndRemove(_id, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
 
-    query = M.findOneAndRemove({}, {select: 'author -title'});
+    query = M.findOneAndRemove({}, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -261,11 +261,11 @@ describe('model: findOneAndRemove:', function() {
 
     let query;
 
-    query = M.findByIdAndRemove(_id, {select: {author: 1, title: 0}});
+    query = M.findByIdAndRemove(_id, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
 
-    query = M.findOneAndRemove({}, {select: {author: 1, title: 0}});
+    query = M.findOneAndRemove({}, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -277,12 +277,12 @@ describe('model: findOneAndRemove:', function() {
 
     let query;
 
-    query = M.findByIdAndRemove(_id, {sort: 'author -title'});
+    query = M.findByIdAndRemove(_id, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
-    query = M.findOneAndRemove({}, {sort: 'author -title'});
+    query = M.findOneAndRemove({}, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -295,12 +295,12 @@ describe('model: findOneAndRemove:', function() {
 
     let query;
 
-    query = M.findByIdAndRemove(_id, {sort: {author: 1, title: -1}});
+    query = M.findByIdAndRemove(_id, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
-    query = M.findOneAndRemove(_id, {sort: {author: 1, title: -1}});
+    query = M.findOneAndRemove(_id, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -308,15 +308,15 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', {name: String});
-    const N = db.model('B', {a: {type: Schema.ObjectId, ref: 'A'}, i: Number});
+    const M = db.model('A', { name: String });
+    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
 
-    M.create({name: 'i am an A'}, function(err, a) {
+    M.create({ name: 'i am an A' }, function(err, a) {
       if (err) return done(err);
-      N.create({a: a._id, i: 10}, function(err, b) {
+      N.create({ a: a._id, i: 10 }, function(err, b) {
         if (err) return done(err);
 
-        N.findOneAndRemove({_id: b._id}, {select: 'a -_id'})
+        N.findOneAndRemove({ _id: b._id }, { select: 'a -_id' })
           .populate('a')
           .exec(function(err, doc) {
             if (err) return done(err);
@@ -354,7 +354,7 @@ describe('model: findOneAndRemove:', function() {
   describe('middleware', function() {
     it('works', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -377,7 +377,7 @@ describe('model: findOneAndRemove:', function() {
         assert.ifError(error);
 
         Breakfast.findOneAndRemove(
-          {base: 'eggs'},
+          { base: 'eggs' },
           {},
           function(error, breakfast) {
             assert.ifError(error);
@@ -391,7 +391,7 @@ describe('model: findOneAndRemove:', function() {
 
     it('works with exec() (gh-439)', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -414,7 +414,7 @@ describe('model: findOneAndRemove:', function() {
         assert.ifError(error);
 
         Breakfast.
-          findOneAndRemove({base: 'eggs'}, {}).
+          findOneAndRemove({ base: 'eggs' }, {}).
           exec(function(error, breakfast) {
             assert.ifError(error);
             assert.equal(breakfast.base, 'eggs');
diff --git a/test/model.findOneAndReplace.test.js b/test/model.findOneAndReplace.test.js
index b3054153f5f..d536db9bb76 100644
--- a/test/model.findOneAndReplace.test.js
+++ b/test/model.findOneAndReplace.test.js
@@ -72,7 +72,7 @@ describe('model: findOneAndReplace:', function() {
 
     collection = 'replaceoneblogposts';
 
-    strictSchema = new Schema({name: String}, {strict: true});
+    strictSchema = new Schema({ name: String }, { strict: true });
     mongoose.model('ReplaceOneStrictSchema', strictSchema);
 
     db = start();
@@ -86,12 +86,12 @@ describe('model: findOneAndReplace:', function() {
     const M = db.model(modelname, collection);
     const title = 'remove muah';
 
-    const post = new M({title: title});
+    const post = new M({ title: title });
 
     return co(function*() {
       yield post.save();
 
-      const doc = yield M.findOneAndReplace({title: title});
+      const doc = yield M.findOneAndReplace({ title: title });
 
       assert.equal(post.id, doc.id);
     });
@@ -104,11 +104,11 @@ describe('model: findOneAndReplace:', function() {
     let query;
 
     // Model.findOneAndReplace
-    query = M.findOneAndReplace({author: 'aaron'}, {}, {select: 'author'});
+    query = M.findOneAndReplace({ author: 'aaron' }, {}, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions.author, 'aaron');
 
-    query = M.findOneAndReplace({author: 'aaron'});
+    query = M.findOneAndReplace({ author: 'aaron' });
     assert.equal(query._fields, undefined);
     assert.equal(query._conditions.author, 'aaron');
 
@@ -118,12 +118,12 @@ describe('model: findOneAndReplace:', function() {
     assert.equal(query._conditions.author, undefined);
 
     // Query.findOneAndReplace
-    query = M.where('author', 'aaron').findOneAndReplace({date: now});
+    query = M.where('author', 'aaron').findOneAndReplace({ date: now });
     assert.equal(query._fields, undefined);
     assert.equal(query._conditions.date, now);
     assert.equal(query._conditions.author, 'aaron');
 
-    query = M.find().findOneAndReplace({author: 'aaron'}, {}, {select: 'author'});
+    query = M.find().findOneAndReplace({ author: 'aaron' }, {}, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions.author, 'aaron');
 
@@ -137,10 +137,10 @@ describe('model: findOneAndReplace:', function() {
     const M = db.model(modelname, collection + random());
     let pending = 5;
 
-    M.findOneAndReplace({name: 'aaron1'}, {select: 'name'}, cb);
-    M.findOneAndReplace({name: 'aaron1'}, cb);
-    M.where().findOneAndReplace({name: 'aaron1'}, {select: 'name'}, cb);
-    M.where().findOneAndReplace({name: 'aaron1'}, cb);
+    M.findOneAndReplace({ name: 'aaron1' }, { select: 'name' }, cb);
+    M.findOneAndReplace({ name: 'aaron1' }, cb);
+    M.where().findOneAndReplace({ name: 'aaron1' }, { select: 'name' }, cb);
+    M.where().findOneAndReplace({ name: 'aaron1' }, cb);
     M.where('name', 'aaron1').findOneAndReplace(cb);
 
     function cb(err, doc) {
@@ -184,7 +184,7 @@ describe('model: findOneAndReplace:', function() {
     const _id = new DocumentObjectId;
     let pending = 2;
 
-    M.findByIdAndDelete(_id, {select: 'name'}, cb);
+    M.findByIdAndDelete(_id, { select: 'name' }, cb);
     M.findByIdAndDelete(_id, cb);
 
     function cb(err, doc) {
@@ -199,7 +199,7 @@ describe('model: findOneAndReplace:', function() {
     const M = db.model(modelname, collection);
     const title = 'remove muah pleez';
 
-    const post = new M({title: title});
+    const post = new M({ title: title });
     post.save(function(err) {
       assert.ifError(err);
       M.findByIdAndDelete(post.id, function(err, doc) {
@@ -221,7 +221,7 @@ describe('model: findOneAndReplace:', function() {
     let query;
 
     // Model.findByIdAndDelete
-    query = M.findByIdAndDelete(_id, {select: 'author'});
+    query = M.findByIdAndDelete(_id, { select: 'author' });
     assert.equal(query._fields.author, 1);
     assert.equal(query._conditions._id.toString(), _id.toString());
 
@@ -239,7 +239,7 @@ describe('model: findOneAndReplace:', function() {
   it('supports v3 select string syntax', function(done) {
     const M = db.model(modelname, collection);
 
-    const query = M.findOneAndReplace({}, {}, {select: 'author -title'});
+    const query = M.findOneAndReplace({}, {}, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -248,7 +248,7 @@ describe('model: findOneAndReplace:', function() {
   it('supports v3 select object syntax', function(done) {
     const M = db.model(modelname, collection);
 
-    const query = M.findOneAndReplace({}, {}, {select: {author: 1, title: 0}});
+    const query = M.findOneAndReplace({}, {}, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -257,7 +257,7 @@ describe('model: findOneAndReplace:', function() {
   it('supports v3 sort string syntax', function(done) {
     const M = db.model(modelname, collection);
 
-    const query = M.findOneAndReplace({}, {}, {sort: 'author -title'});
+    const query = M.findOneAndReplace({}, {}, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -267,7 +267,7 @@ describe('model: findOneAndReplace:', function() {
   it('supports v3 sort object syntax', function(done) {
     const M = db.model(modelname, collection);
 
-    const query = M.findOneAndReplace({}, {}, {sort: {author: 1, title: -1}});
+    const query = M.findOneAndReplace({}, {}, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -275,15 +275,15 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', {name: String});
-    const N = db.model('B', {a: {type: Schema.ObjectId, ref: 'A'}, i: Number});
+    const M = db.model('A', { name: String });
+    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
 
-    M.create({name: 'i am an A'}, function(err, a) {
+    M.create({ name: 'i am an A' }, function(err, a) {
       if (err) return done(err);
-      N.create({a: a._id, i: 10}, function(err, b) {
+      N.create({ a: a._id, i: 10 }, function(err, b) {
         if (err) return done(err);
 
-        N.findOneAndReplace({_id: b._id}, {a: a._id})
+        N.findOneAndReplace({ _id: b._id }, { a: a._id })
           .populate('a')
           .exec(function(err, doc) {
             if (err) return done(err);
@@ -320,7 +320,7 @@ describe('model: findOneAndReplace:', function() {
   describe('middleware', function() {
     it('works', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -343,7 +343,7 @@ describe('model: findOneAndReplace:', function() {
         assert.ifError(error);
 
         Breakfast.findOneAndReplace(
-          {base: 'eggs'},
+          { base: 'eggs' },
           {},
           function(error, breakfast) {
             assert.ifError(error);
@@ -357,7 +357,7 @@ describe('model: findOneAndReplace:', function() {
 
     it('works with exec() (gh-439)', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -380,7 +380,7 @@ describe('model: findOneAndReplace:', function() {
         assert.ifError(error);
 
         Breakfast.
-          findOneAndReplace({base: 'eggs'}, {}).
+          findOneAndReplace({ base: 'eggs' }, {}).
           exec(function(error, breakfast) {
             assert.ifError(error);
             assert.equal(breakfast.base, 'eggs');
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 9e040c8d0ae..6a03b9fe9be 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -78,10 +78,10 @@ describe('model: findOneAndUpdate:', function() {
 
     collection = 'updateoneblogposts_' + random();
 
-    strictSchema = new Schema({name: String}, {strict: true});
+    strictSchema = new Schema({ name: String }, { strict: true });
     mongoose.model('UpdateOneStrictSchema', strictSchema);
 
-    strictThrowSchema = new Schema({name: String}, {strict: 'throw'});
+    strictThrowSchema = new Schema({ name: String }, { strict: 'throw' });
     mongoose.model('UpdateOneStrictThrowSchema', strictThrowSchema);
 
     db = start();
@@ -109,10 +109,10 @@ describe('model: findOneAndUpdate:', function() {
     post.meta.visitors = 0;
     post.date = new Date;
     post.published = true;
-    post.mixed = {x: 'ex'};
+    post.mixed = { x: 'ex' };
     post.numbers = [4, 5, 6, 7];
     post.owners = [id0, id1];
-    post.comments = [{body: 'been there'}, {body: 'done that'}];
+    post.comments = [{ body: 'been there' }, { body: 'done that' }];
 
     post.save(function(err) {
       assert.ifError(err);
@@ -138,16 +138,16 @@ describe('model: findOneAndUpdate:', function() {
 
         const update = {
           title: newTitle, // becomes $set
-          $inc: {'meta.visitors': 2},
-          $set: {date: new Date},
+          $inc: { 'meta.visitors': 2 },
+          $set: { date: new Date },
           published: false, // becomes $set
-          mixed: {x: 'ECKS', y: 'why'}, // $set
-          $pullAll: {numbers: [4, 6]},
-          $pull: {owners: id0},
+          mixed: { x: 'ECKS', y: 'why' }, // $set
+          $pullAll: { numbers: [4, 6] },
+          $pull: { owners: id0 },
           'comments.1.body': 8 // $set
         };
 
-        M.findOneAndUpdate({title: title}, update, {new: true}, function(err, up) {
+        M.findOneAndUpdate({ title: title }, update, { new: true }, function(err, up) {
           assert.equal(err && err.stack, err, null);
 
           assert.equal(up.title, newTitle);
@@ -187,7 +187,7 @@ describe('model: findOneAndUpdate:', function() {
           zipcode: String
         },
         age: Number
-      }, {_id: false});
+      }, { _id: false });
       const itemSchema = new Schema({
         items: [itemSpec]
       });
@@ -214,13 +214,13 @@ describe('model: findOneAndUpdate:', function() {
           zipcode: '1002?'
         }
       });
-      const itemParent = new ItemParentModel({items: [item1, item2, item3]});
+      const itemParent = new ItemParentModel({ items: [item1, item2, item3] });
       itemParent.save(function(err) {
         assert.ifError(err);
         ItemParentModel.findOneAndUpdate(
-          {_id: itemParent._id, 'items.item_id': item1.item_id},
-          {$set: {'items.$.address': {}}},
-          {new: true},
+          { _id: itemParent._id, 'items.item_id': item1.item_id },
+          { $set: { 'items.$.address': {} } },
+          { new: true },
           function(err, updatedDoc) {
             assert.ifError(err);
             assert.ok(updatedDoc.items);
@@ -249,10 +249,10 @@ describe('model: findOneAndUpdate:', function() {
     post.meta.visitors = 0;
     post.date = new Date;
     post.published = true;
-    post.mixed = {x: 'ex'};
+    post.mixed = { x: 'ex' };
     post.numbers = [4, 5, 6, 7];
     post.owners = [id0, id1];
-    post.comments = [{body: 'been there'}, {body: 'done that'}];
+    post.comments = [{ body: 'been there' }, { body: 'done that' }];
 
     post.save(function(err) {
       assert.ifError(err);
@@ -261,16 +261,16 @@ describe('model: findOneAndUpdate:', function() {
 
         const update = {
           title: newTitle, // becomes $set
-          $inc: {'meta.visitors': 2},
-          $set: {date: new Date},
+          $inc: { 'meta.visitors': 2 },
+          $set: { date: new Date },
           published: false, // becomes $set
-          mixed: {x: 'ECKS', y: 'why'}, // $set
-          $pullAll: {numbers: [4, 6]},
-          $pull: {owners: id0},
+          mixed: { x: 'ECKS', y: 'why' }, // $set
+          $pullAll: { numbers: [4, 6] },
+          $pull: { owners: id0 },
           'comments.1.body': 8 // $set
         };
 
-        M.findOneAndUpdate({title: title}, update, {new: false}, function(err, up) {
+        M.findOneAndUpdate({ title: title }, update, { new: false }, function(err, up) {
           assert.ifError(err);
 
           assert.equal(up.title, post.title);
@@ -309,22 +309,22 @@ describe('model: findOneAndUpdate:', function() {
     post.meta.visitors = 0;
     post.date = new Date;
     post.published = true;
-    post.mixed = {x: 'ex'};
+    post.mixed = { x: 'ex' };
     post.numbers = [4, 5, 6, 7];
     post.owners = [id0, id1];
-    post.comments = [{body: 'been there'}, {body: 'done that'}];
+    post.comments = [{ body: 'been there' }, { body: 'done that' }];
 
     const update = {
       title: newTitle, // becomes $set
-      $inc: {'meta.visitors': 2},
-      $set: {date: new Date},
+      $inc: { 'meta.visitors': 2 },
+      $set: { date: new Date },
       published: false, // becomes $set
-      mixed: {x: 'ECKS', y: 'why'}, // $set
-      $pullAll: {numbers: [4, 6]},
-      $pull: {owners: id0}
+      mixed: { x: 'ECKS', y: 'why' }, // $set
+      $pullAll: { numbers: [4, 6] },
+      $pull: { owners: id0 }
     };
 
-    M.findOneAndUpdate({title: title}, update, {upsert: true, new: true}, function(err, up) {
+    M.findOneAndUpdate({ title: title }, update, { upsert: true, new: true }, function(err, up) {
       assert.ifError(err);
 
       assert.equal(up.title, newTitle);
@@ -348,18 +348,18 @@ describe('model: findOneAndUpdate:', function() {
     let query;
 
     // Model.findOneAndUpdate
-    query = M.findOneAndUpdate({author: 'aaron'}, {$set: {date: now}}, {new: false, fields: 'author'});
+    query = M.findOneAndUpdate({ author: 'aaron' }, { $set: { date: now } }, { new: false, fields: 'author' });
     assert.strictEqual(false, query.options.new);
     assert.strictEqual(1, query._fields.author);
     assert.equal(query._update.$set.date.toString(), now.toString());
     assert.strictEqual('aaron', query._conditions.author);
 
-    query = M.findOneAndUpdate({author: 'aaron'}, {$set: {date: now}});
+    query = M.findOneAndUpdate({ author: 'aaron' }, { $set: { date: now } });
     assert.strictEqual(undefined, query.options.new);
     assert.equal(query._update.$set.date.toString(), now.toString());
     assert.strictEqual('aaron', query._conditions.author);
 
-    query = M.findOneAndUpdate({$set: {date: now}});
+    query = M.findOneAndUpdate({ $set: { date: now } });
     assert.strictEqual(undefined, query.options.new);
     assert.equal(query._update.$set.date.toString(), now.toString());
     assert.strictEqual(undefined, query._conditions.author);
@@ -370,17 +370,17 @@ describe('model: findOneAndUpdate:', function() {
     assert.strictEqual(undefined, query._conditions.author);
 
     // Query.findOneAndUpdate
-    query = M.where('author', 'aaron').findOneAndUpdate({date: now});
+    query = M.where('author', 'aaron').findOneAndUpdate({ date: now });
     assert.strictEqual(undefined, query.options.new);
     assert.equal(query._update.date.toString(), now.toString());
     assert.strictEqual('aaron', query._conditions.author);
 
-    query = M.find().findOneAndUpdate({author: 'aaron'}, {date: now});
+    query = M.find().findOneAndUpdate({ author: 'aaron' }, { date: now });
     assert.strictEqual(undefined, query.options.new);
     assert.equal(query._update.date.toString(), now.toString());
     assert.strictEqual('aaron', query._conditions.author);
 
-    query = M.find().findOneAndUpdate({date: now});
+    query = M.find().findOneAndUpdate({ date: now });
     assert.strictEqual(undefined, query.options.new);
     assert.equal(query._update.date.toString(), now.toString());
     assert.strictEqual(undefined, query._conditions.author);
@@ -396,12 +396,12 @@ describe('model: findOneAndUpdate:', function() {
     const M = db.model(modelname, collection + random());
     let pending = 6;
 
-    M.findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron6'}}, {new: false}, cb);
-    M.findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron4'}}, cb);
-    M.where().findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron1'}}, {new: false}, cb);
-    M.where().findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron2'}}, cb);
-    M.where().findOneAndUpdate({$set: {name: 'Aaron6'}}, cb);
-    M.where('name', 'aaron').findOneAndUpdate({$set: {name: 'Aaron'}}).findOneAndUpdate(cb);
+    M.findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron6' } }, { new: false }, cb);
+    M.findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron4' } }, cb);
+    M.where().findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron1' } }, { new: false }, cb);
+    M.where().findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron2' } }, cb);
+    M.where().findOneAndUpdate({ $set: { name: 'Aaron6' } }, cb);
+    M.where('name', 'aaron').findOneAndUpdate({ $set: { name: 'Aaron' } }).findOneAndUpdate(cb);
 
     function cb(err, doc) {
       assert.ifError(err);
@@ -417,12 +417,12 @@ describe('model: findOneAndUpdate:', function() {
     const M = db.model(modelname, collection + random());
     let pending = 6;
 
-    M.findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron'}}, {new: false}).exec(cb);
-    M.findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron'}}).exec(cb);
-    M.where().findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron'}}, {new: false}).exec(cb);
-    M.where().findOneAndUpdate({name: 'aaron'}, {$set: {name: 'Aaron'}}).exec(cb);
-    M.where().findOneAndUpdate({$set: {name: 'Aaron'}}).exec(cb);
-    M.where('name', 'aaron').findOneAndUpdate({$set: {name: 'Aaron'}}).exec(cb);
+    M.findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron' } }, { new: false }).exec(cb);
+    M.findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron' } }).exec(cb);
+    M.where().findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron' } }, { new: false }).exec(cb);
+    M.where().findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron' } }).exec(cb);
+    M.where().findOneAndUpdate({ $set: { name: 'Aaron' } }).exec(cb);
+    M.where('name', 'aaron').findOneAndUpdate({ $set: { name: 'Aaron' } }).exec(cb);
 
     function cb(err, doc) {
       assert.ifError(err);
@@ -466,11 +466,11 @@ describe('model: findOneAndUpdate:', function() {
 
       for (let i = 0; i < 4; ++i) {
         BlogPost
-          .findOneAndUpdate({_id: post._id}, {$inc: {'meta.visitors': 1}}, callback);
+          .findOneAndUpdate({ _id: post._id }, { $inc: { 'meta.visitors': 1 } }, callback);
       }
 
       function complete() {
-        BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+        BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.get('meta.visitors'), 9);
           done();
@@ -481,24 +481,24 @@ describe('model: findOneAndUpdate:', function() {
 
   it('honors strict schemas', function(done) {
     const S = db.model('UpdateOneStrictSchema');
-    const s = new S({name: 'orange crush'});
+    const s = new S({ name: 'orange crush' });
 
     s.save(function(err) {
       assert.ifError(err);
       const name = Date.now();
-      S.findOneAndUpdate({name: name}, {ignore: true}, {upsert: true, new: true}, function(err, doc) {
+      S.findOneAndUpdate({ name: name }, { ignore: true }, { upsert: true, new: true }, function(err, doc) {
         assert.ifError(err);
         assert.ok(doc);
         assert.ok(doc._id);
         assert.equal(doc.ignore, undefined);
         assert.equal(doc._doc.ignore, undefined);
         assert.equal(doc.name, name);
-        S.findOneAndUpdate({name: 'orange crush'}, {ignore: true}, {upsert: true}, function(err, doc) {
+        S.findOneAndUpdate({ name: 'orange crush' }, { ignore: true }, { upsert: true }, function(err, doc) {
           assert.ifError(err);
           assert.ok(!doc.ignore);
           assert.ok(!doc._doc.ignore);
           assert.equal(doc.name, 'orange crush');
-          S.findOneAndUpdate({name: 'orange crush'}, {ignore: true}, function(err, doc) {
+          S.findOneAndUpdate({ name: 'orange crush' }, { ignore: true }, function(err, doc) {
             assert.ifError(err);
             assert.ok(!doc.ignore);
             assert.ok(!doc._doc.ignore);
@@ -512,18 +512,18 @@ describe('model: findOneAndUpdate:', function() {
 
   it('returns errors with strict:throw schemas', function(done) {
     const S = db.model('UpdateOneStrictThrowSchema');
-    const s = new S({name: 'orange crush'});
+    const s = new S({ name: 'orange crush' });
 
     s.save(function(err) {
       assert.ifError(err);
 
       const name = Date.now();
-      S.findOneAndUpdate({name: name}, {ignore: true}, {upsert: true}, function(err, doc) {
+      S.findOneAndUpdate({ name: name }, { ignore: true }, { upsert: true }, function(err, doc) {
         assert.ok(err);
         assert.ok(/not in schema/.test(err));
         assert.ok(!doc);
 
-        S.findOneAndUpdate({_id: s._id}, {ignore: true}, function(err, doc) {
+        S.findOneAndUpdate({ _id: s._id }, { ignore: true }, function(err, doc) {
           assert.ok(err);
           assert.ok(/not in schema/.test(err));
           assert.ok(!doc);
@@ -553,8 +553,8 @@ describe('model: findOneAndUpdate:', function() {
     const _id = new DocumentObjectId;
     let pending = 2;
 
-    M.findByIdAndUpdate(_id, {$set: {name: 'Aaron'}}, {new: false}, cb);
-    M.findByIdAndUpdate(_id, {$set: {name: 'changed'}}, cb);
+    M.findByIdAndUpdate(_id, { $set: { name: 'Aaron' } }, { new: false }, cb);
+    M.findByIdAndUpdate(_id, { $set: { name: 'changed' } }, cb);
 
     function cb(err, doc) {
       assert.ifError(err);
@@ -571,8 +571,8 @@ describe('model: findOneAndUpdate:', function() {
     const _id = new DocumentObjectId;
     let pending = 2;
 
-    M.findByIdAndUpdate(_id, {$set: {name: 'Aaron'}}, {new: false}).exec(cb);
-    M.findByIdAndUpdate(_id, {$set: {name: 'changed'}}).exec(cb);
+    M.findByIdAndUpdate(_id, { $set: { name: 'Aaron' } }, { new: false }).exec(cb);
+    M.findByIdAndUpdate(_id, { $set: { name: 'changed' } }).exec(cb);
 
     function cb(err, doc) {
       assert.ifError(err);
@@ -598,10 +598,10 @@ describe('model: findOneAndUpdate:', function() {
     post.meta.visitors = 0;
     post.date = new Date;
     post.published = true;
-    post.mixed = {x: 'ex'};
+    post.mixed = { x: 'ex' };
     post.numbers = [4, 5, 6, 7];
     post.owners = [id0, id1];
-    post.comments = [{body: 'been there'}, {body: 'done that'}];
+    post.comments = [{ body: 'been there' }, { body: 'done that' }];
 
     post.save(function(err) {
       assert.ifError(err);
@@ -610,16 +610,16 @@ describe('model: findOneAndUpdate:', function() {
 
         const update = {
           title: newTitle, // becomes $set
-          $inc: {'meta.visitors': 2},
-          $set: {date: new Date},
+          $inc: { 'meta.visitors': 2 },
+          $set: { date: new Date },
           published: false, // becomes $set
-          mixed: {x: 'ECKS', y: 'why'}, // $set
-          $pullAll: {numbers: [4, 6]},
-          $pull: {owners: id0},
+          mixed: { x: 'ECKS', y: 'why' }, // $set
+          $pullAll: { numbers: [4, 6] },
+          $pull: { owners: id0 },
           'comments.1.body': 8 // $set
         };
 
-        M.findByIdAndUpdate(post.id, update, {new: false}, function(err, up) {
+        M.findByIdAndUpdate(post.id, update, { new: false }, function(err, up) {
           assert.ifError(err);
 
           assert.equal(post.title, up.title);
@@ -652,13 +652,13 @@ describe('model: findOneAndUpdate:', function() {
     let query;
 
     // Model.findByIdAndUpdate
-    query = M.findByIdAndUpdate(_id, {$set: {date: now}}, {new: false, fields: 'author'});
+    query = M.findByIdAndUpdate(_id, { $set: { date: now } }, { new: false, fields: 'author' });
     assert.strictEqual(false, query.options.new);
     assert.strictEqual(1, query._fields.author);
     assert.equal(query._update.$set.date.toString(), now.toString());
     assert.strictEqual(_id.toString(), query._conditions._id.toString());
 
-    query = M.findByIdAndUpdate(_id, {$set: {date: now}});
+    query = M.findByIdAndUpdate(_id, { $set: { date: now } });
     assert.strictEqual(undefined, query.options.new);
     assert.equal(query._update.$set.date.toString(), now.toString());
     assert.strictEqual(_id.toString(), query._conditions._id.toString());
@@ -681,11 +681,11 @@ describe('model: findOneAndUpdate:', function() {
     const now = new Date;
     let query;
 
-    query = M.findByIdAndUpdate(_id, {$set: {date: now}}, {select: 'author -title'});
+    query = M.findByIdAndUpdate(_id, { $set: { date: now } }, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
 
-    query = M.findOneAndUpdate({}, {$set: {date: now}}, {select: 'author -title'});
+    query = M.findOneAndUpdate({}, { $set: { date: now } }, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -698,11 +698,11 @@ describe('model: findOneAndUpdate:', function() {
     const now = new Date;
     let query;
 
-    query = M.findByIdAndUpdate(_id, {$set: {date: now}}, {select: {author: 1, title: 0}});
+    query = M.findByIdAndUpdate(_id, { $set: { date: now } }, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
 
-    query = M.findOneAndUpdate({}, {$set: {date: now}}, {select: {author: 1, title: 0}});
+    query = M.findOneAndUpdate({}, { $set: { date: now } }, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
     assert.strictEqual(0, query._fields.title);
     done();
@@ -715,28 +715,28 @@ describe('model: findOneAndUpdate:', function() {
     const _id = new DocumentObjectId;
     let query;
 
-    query = M.findByIdAndUpdate(_id, {$set: {date: now}}, {sort: 'author -title'});
+    query = M.findByIdAndUpdate(_id, { $set: { date: now } }, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
-    query = M.findOneAndUpdate({}, {$set: {date: now}}, {sort: 'author -title'});
+    query = M.findOneAndUpdate({}, { $set: { date: now } }, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
     // gh-1887
     M.create(
-      {title: 1, meta: {visitors: 0}}
-      , {title: 2, meta: {visitors: 10}}
-      , {title: 3, meta: {visitors: 5}}
+      { title: 1, meta: { visitors: 0 } }
+      , { title: 2, meta: { visitors: 10 } }
+      , { title: 3, meta: { visitors: 5 } }
       , function(err) {
         if (err) {
           return done(err);
         }
 
-        M.findOneAndUpdate({}, {title: 'changed'})
-          .sort({'meta.visitors': -1})
+        M.findOneAndUpdate({}, { title: 'changed' })
+          .sort({ 'meta.visitors': -1 })
           .exec(function(err, doc) {
             if (err) {
               return done(err);
@@ -754,12 +754,12 @@ describe('model: findOneAndUpdate:', function() {
     const now = new Date;
     let query;
 
-    query = M.findByIdAndUpdate(_id, {$set: {date: now}}, {sort: {author: 1, title: -1}});
+    query = M.findByIdAndUpdate(_id, { $set: { date: now } }, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
 
-    query = M.findOneAndUpdate(_id, {$set: {date: now}}, {sort: {author: 1, title: -1}});
+    query = M.findOneAndUpdate(_id, { $set: { date: now } }, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
     assert.equal(query.options.sort.author, 1);
     assert.equal(query.options.sort.title, -1);
@@ -769,7 +769,7 @@ describe('model: findOneAndUpdate:', function() {
 
   it('supports $elemMatch with $in (gh-1091 gh-1100)', function(done) {
     const postSchema = new Schema({
-      ids: [{type: Schema.ObjectId}],
+      ids: [{ type: Schema.ObjectId }],
       title: String
     });
 
@@ -777,12 +777,12 @@ describe('model: findOneAndUpdate:', function() {
     const _id1 = new mongoose.Types.ObjectId;
     const _id2 = new mongoose.Types.ObjectId;
 
-    B.create({ids: [_id1, _id2]}, function(err, doc) {
+    B.create({ ids: [_id1, _id2] }, function(err, doc) {
       assert.ifError(err);
 
       B
-        .findByIdAndUpdate(doc._id, {title: 'woot'}, {new: true})
-        .select({title: 1, ids: {$elemMatch: {$in: [_id2.toString()]}}})
+        .findByIdAndUpdate(doc._id, { title: 'woot' }, { new: true })
+        .select({ title: 1, ids: { $elemMatch: { $in: [_id2.toString()] } } })
         .exec(function(err, found) {
           assert.ifError(err);
           assert.ok(found);
@@ -796,19 +796,19 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', {name: String});
-    const N = db.model('B', {a: {type: Schema.ObjectId, ref: 'A'}, i: Number});
+    const M = db.model('A', { name: String });
+    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
 
-    M.create({name: 'i am an A'}, function(err, a) {
+    M.create({ name: 'i am an A' }, function(err, a) {
       if (err) {
         return done(err);
       }
-      N.create({a: a._id, i: 10}, function(err, b) {
+      N.create({ a: a._id, i: 10 }, function(err, b) {
         if (err) {
           return done(err);
         }
 
-        N.findOneAndUpdate({_id: b._id}, {$inc: {i: 1}})
+        N.findOneAndUpdate({ _id: b._id }, { $inc: { i: 1 } })
           .populate('a')
           .exec(function(err, doc) {
             if (err) {
@@ -834,10 +834,10 @@ describe('model: findOneAndUpdate:', function() {
     const Thing = db.model('Thing', thingSchema);
     const key = 'some-id';
 
-    Thing.findOneAndUpdate({_id: key}, {$set: {flag: false}}, {upsert: true, new: false}).exec(function(err, thing) {
+    Thing.findOneAndUpdate({ _id: key }, { $set: { flag: false } }, { upsert: true, new: false }).exec(function(err, thing) {
       assert.ifError(err);
       assert.equal(thing, null);
-      Thing.findOneAndUpdate({_id: key}, {$set: {flag: false}}, {upsert: true, new: false}).exec(function(err, thing2) {
+      Thing.findOneAndUpdate({ _id: key }, { $set: { flag: false } }, { upsert: true, new: false }).exec(function(err, thing2) {
         assert.ifError(err);
         assert.equal(thing2.id, key);
         assert.equal(thing2.flag, false);
@@ -854,11 +854,11 @@ describe('model: findOneAndUpdate:', function() {
     return co(function*() {
       let fruit = yield Fruit.create({ name: 'Apple' });
 
-      fruit = yield Fruit.findOneAndUpdate({}, { $set: { name: 'Banana' }},
+      fruit = yield Fruit.findOneAndUpdate({}, { $set: { name: 'Banana' } },
         { new: true, useFindAndModify: false });
       assert.ok(fruit instanceof mongoose.Document);
 
-      fruit = yield Fruit.findOneAndUpdate({}, { $set: { name: 'Cherry' }},
+      fruit = yield Fruit.findOneAndUpdate({}, { $set: { name: 'Cherry' } },
         { new: true, useFindAndModify: true });
       assert.ok(fruit instanceof mongoose.Document);
     });
@@ -875,10 +875,10 @@ describe('model: findOneAndUpdate:', function() {
     const Thing = db.model('Test', thingSchema);
     const key = 'some-new-id';
 
-    Thing.findOneAndUpdate({_id: key}, {$set: {flag: false}}, {upsert: true, new: false, rawResult: true}).exec(function(err, rawResult) {
+    Thing.findOneAndUpdate({ _id: key }, { $set: { flag: false } }, { upsert: true, new: false, rawResult: true }).exec(function(err, rawResult) {
       assert.ifError(err);
       assert.equal(rawResult.lastErrorObject.updatedExisting, false );
-      Thing.findOneAndUpdate({_id: key}, {$set: {flag: true}}, {upsert: true, new: false, rawResult: true}).exec(function(err, rawResult2) {
+      Thing.findOneAndUpdate({ _id: key }, { $set: { flag: true } }, { upsert: true, new: false, rawResult: true }).exec(function(err, rawResult2) {
         assert.ifError(err);
         assert.equal(rawResult2.lastErrorObject.updatedExisting, true );
         assert.equal(rawResult2.value._id, key);
@@ -895,11 +895,11 @@ describe('model: findOneAndUpdate:', function() {
 
     const Thing = db.model('Thing1', thingSchema);
 
-    Thing.create({name: ['Test']}, function(err, thing) {
+    Thing.create({ name: ['Test'] }, function(err, thing) {
       if (err) {
         return done(err);
       }
-      Thing.findOneAndUpdate({_id: thing._id}, {name: null}, {new: true})
+      Thing.findOneAndUpdate({ _id: thing._id }, { name: null }, { new: true })
         .exec(function(err, doc) {
           if (err) {
             return done(err);
@@ -912,12 +912,12 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('honors the overwrite option (gh-1809)', function(done) {
-    const M = db.model('1809', {name: String, change: Boolean});
-    M.create({name: 'first'}, function(err, doc) {
+    const M = db.model('1809', { name: String, change: Boolean });
+    M.create({ name: 'first' }, function(err, doc) {
       if (err) {
         return done(err);
       }
-      M.findByIdAndUpdate(doc._id, {change: true}, {overwrite: true, new: true}, function(err, doc) {
+      M.findByIdAndUpdate(doc._id, { change: true }, { overwrite: true, new: true }, function(err, doc) {
         if (err) {
           return done(err);
         }
@@ -932,24 +932,24 @@ describe('model: findOneAndUpdate:', function() {
     const accountSchema = new Schema({
       name: String,
       contacts: [{
-        account: {type: Schema.Types.ObjectId, ref: 'Account'},
+        account: { type: Schema.Types.ObjectId, ref: 'Account' },
         name: String
       }]
     });
 
     const Account = db.model('2070', accountSchema);
 
-    const a1 = new Account({name: 'parent'});
-    const a2 = new Account({name: 'child'});
+    const a1 = new Account({ name: 'parent' });
+    const a2 = new Account({ name: 'child' });
 
     a1.save(function(error) {
       assert.ifError(error);
       a2.save(function(error, a2) {
         assert.ifError(error);
         Account.findOneAndUpdate(
-          {name: 'parent'},
-          {$push: {contacts: {account: a2._id, name: 'child'}}},
-          {new: true},
+          { name: 'parent' },
+          { $push: { contacts: { account: a2._id, name: 'child' } } },
+          { new: true },
           function(error, doc) {
             assert.ifError(error);
             assert.ok(Utils.deepEqual(doc.contacts[0].account, a2._id));
@@ -961,7 +961,7 @@ describe('model: findOneAndUpdate:', function() {
               assert.ok(isEqual(doc.contacts[0].account, a2._id));
             }
 
-            Account.findOne({name: 'parent'}, function(error, doc) {
+            Account.findOne({ name: 'parent' }, function(error, doc) {
               assert.ifError(error);
               assert.ok(Utils.deepEqual(doc.contacts[0].account, a2._id));
               assert.ok(isEqualWith(doc.contacts[0].account, a2._id, compareBuffers));
@@ -989,9 +989,9 @@ describe('model: findOneAndUpdate:', function() {
     const Account = db.model('2122', accountSchema);
 
     Account.findOneAndUpdate(
-      {name: 'account'},
-      {name: 'test'},
-      {upsert: true, new: true},
+      { name: 'account' },
+      { name: 'test' },
+      { upsert: true, new: true },
       function(error, doc) {
         assert.ifError(error);
         assert.equal(doc.__v, 0);
@@ -1035,14 +1035,14 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('works with nested schemas and $pull+$or (gh-1932)', function(done) {
-    const TickSchema = new Schema({name: String});
-    const TestSchema = new Schema({a: Number, b: Number, ticks: [TickSchema]});
+    const TickSchema = new Schema({ name: String });
+    const TestSchema = new Schema({ a: Number, b: Number, ticks: [TickSchema] });
 
     const TestModel = db.model('Test', TestSchema);
 
-    TestModel.create({a: 1, b: 0, ticks: [{name: 'eggs'}, {name: 'bacon'}, {name: 'coffee'}]}, function(error) {
+    TestModel.create({ a: 1, b: 0, ticks: [{ name: 'eggs' }, { name: 'bacon' }, { name: 'coffee' }] }, function(error) {
       assert.ifError(error);
-      TestModel.findOneAndUpdate({a: 1}, {$pull: {ticks: {$or: [{name: 'eggs'}, {name: 'bacon'}]}}},
+      TestModel.findOneAndUpdate({ a: 1 }, { $pull: { ticks: { $or: [{ name: 'eggs' }, { name: 'bacon' }] } } },
         function(error) {
           assert.ifError(error);
           TestModel.findOne({}, function(error, doc) {
@@ -1064,7 +1064,7 @@ describe('model: findOneAndUpdate:', function() {
     const Breakfast = db.model('Test', s);
 
     Breakfast.
-      findOneAndUpdate({}, {time: undefined, base: undefined}, {}).
+      findOneAndUpdate({}, { time: undefined, base: undefined }, {}).
       exec(function(error) {
         assert.ifError(error);
         done();
@@ -1079,7 +1079,7 @@ describe('model: findOneAndUpdate:', function() {
     const Breakfast = db.model('Test', s);
 
     Breakfast.
-      findOneAndUpdate({}, {base: {}}, {}).
+      findOneAndUpdate({}, { base: {} }, {}).
       exec(function(error) {
         assert.ok(error);
         done();
@@ -1089,12 +1089,12 @@ describe('model: findOneAndUpdate:', function() {
   it('strict mode with objects (gh-2947)', function(done) {
     const s = new Schema({
       test: String
-    }, {strict: true});
+    }, { strict: true });
 
     const Breakfast = db.model('Test', s);
     const q = Breakfast.findOneAndUpdate({},
-      {notInSchema: {a: 1}, test: 'abc'},
-      {new: true, strict: true, upsert: true});
+      { notInSchema: { a: 1 }, test: 'abc' },
+      { new: true, strict: true, upsert: true });
 
     q.lean();
     q.exec(function(error, doc) {
@@ -1106,7 +1106,7 @@ describe('model: findOneAndUpdate:', function() {
   describe('middleware', function() {
     it('works', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -1124,7 +1124,7 @@ describe('model: findOneAndUpdate:', function() {
 
       Breakfast.findOneAndUpdate(
         {},
-        {base: 'eggs'},
+        { base: 'eggs' },
         {},
         function(error) {
           assert.ifError(error);
@@ -1136,7 +1136,7 @@ describe('model: findOneAndUpdate:', function() {
 
     it('works with exec()', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
 
@@ -1153,7 +1153,7 @@ describe('model: findOneAndUpdate:', function() {
       const Breakfast = db.model('Test', s);
 
       Breakfast.
-        findOneAndUpdate({}, {base: 'eggs'}, {}).
+        findOneAndUpdate({}, { base: 'eggs' }, {}).
         exec(function(error) {
           assert.ifError(error);
           assert.equal(preCount, 1);
@@ -1166,21 +1166,21 @@ describe('model: findOneAndUpdate:', function() {
   describe('validators (gh-860)', function() {
     it('applies defaults on upsert', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
       const Breakfast = db.model('fam-gh-860-0', s);
 
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true, new: true};
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true, new: true };
       Breakfast.findOneAndUpdate(
         {},
-        {base: 'eggs'},
+        { base: 'eggs' },
         updateOptions,
         function(error, breakfast) {
           assert.ifError(error);
           assert.equal(breakfast.base, 'eggs');
           assert.equal(breakfast.topping, 'bacon');
-          Breakfast.countDocuments({topping: 'bacon'}, function(error, count) {
+          Breakfast.countDocuments({ topping: 'bacon' }, function(error, count) {
             assert.ifError(error);
             assert.equal(1, count);
             done();
@@ -1190,16 +1190,16 @@ describe('model: findOneAndUpdate:', function() {
 
     it('doesnt set default on upsert if query sets it', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
-        numEggs: {type: Number, default: 3},
+        topping: { type: String, default: 'bacon' },
+        numEggs: { type: Number, default: 3 },
         base: String
       }, { versionKey: null });
       const Breakfast = db.model('fam-gh-860-1', s);
 
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true, new: true};
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true, new: true };
       Breakfast.findOneAndUpdate(
-        {topping: 'sausage', numEggs: 4},
-        {base: 'eggs'},
+        { topping: 'sausage', numEggs: 4 },
+        { base: 'eggs' },
         updateOptions,
         function(error, breakfast) {
           assert.ifError(error);
@@ -1212,21 +1212,21 @@ describe('model: findOneAndUpdate:', function() {
 
     it('properly sets default on upsert if query wont set it', function(done) {
       const s = new Schema({
-        topping: {type: String, default: 'bacon'},
+        topping: { type: String, default: 'bacon' },
         base: String
       });
       const Breakfast = db.model('fam-gh-860-2', s);
 
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true, new: true};
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true, new: true };
       Breakfast.findOneAndUpdate(
-        {topping: {$ne: 'sausage'}},
-        {base: 'eggs'},
+        { topping: { $ne: 'sausage' } },
+        { base: 'eggs' },
         updateOptions,
         function(error, breakfast) {
           assert.ifError(error);
           assert.equal(breakfast.base, 'eggs');
           assert.equal(breakfast.topping, 'bacon');
-          Breakfast.countDocuments({topping: 'bacon'}, function(error, count) {
+          Breakfast.countDocuments({ topping: 'bacon' }, function(error, count) {
             assert.ifError(error);
             assert.equal(1, count);
             done();
@@ -1279,7 +1279,7 @@ describe('model: findOneAndUpdate:', function() {
       };
       Breakfast.findOneAndUpdate(
         {},
-        {topping: 'bacon', base: 'eggs'},
+        { topping: 'bacon', base: 'eggs' },
         updateOptions,
         function(error, breakfast) {
           assert.ok(!!error);
@@ -1295,7 +1295,7 @@ describe('model: findOneAndUpdate:', function() {
 
     it('validators handle $unset and $setOnInsert', function(done) {
       const s = new Schema({
-        steak: {type: String, required: true},
+        steak: { type: String, required: true },
         eggs: {
           type: String, validate: function() {
             return false;
@@ -1304,10 +1304,10 @@ describe('model: findOneAndUpdate:', function() {
       });
       const Breakfast = db.model('fam-gh-860-4', s);
 
-      const updateOptions = {runValidators: true, new: true};
+      const updateOptions = { runValidators: true, new: true };
       Breakfast.findOneAndUpdate(
         {},
-        {$unset: {steak: ''}, $setOnInsert: {eggs: 'softboiled'}},
+        { $unset: { steak: '' }, $setOnInsert: { eggs: 'softboiled' } },
         updateOptions,
         function(error, breakfast) {
           assert.ok(!!error);
@@ -1323,16 +1323,16 @@ describe('model: findOneAndUpdate:', function() {
 
     it('min/max, enum, and regex built-in validators work', function(done) {
       const s = new Schema({
-        steak: {type: String, enum: ['ribeye', 'sirloin']},
-        eggs: {type: Number, min: 4, max: 6},
-        bacon: {type: String, match: /strips/}
+        steak: { type: String, enum: ['ribeye', 'sirloin'] },
+        eggs: { type: Number, min: 4, max: 6 },
+        bacon: { type: String, match: /strips/ }
       });
       const Breakfast = db.model('fam-gh-860-5', s);
 
-      const updateOptions = {runValidators: true, new: true};
+      const updateOptions = { runValidators: true, new: true };
       Breakfast.findOneAndUpdate(
         {},
-        {$set: {steak: 'ribeye', eggs: 3, bacon: '3 strips'}},
+        { $set: { steak: 'ribeye', eggs: 3, bacon: '3 strips' } },
         updateOptions,
         function(error) {
           assert.ok(!!error);
@@ -1342,7 +1342,7 @@ describe('model: findOneAndUpdate:', function() {
 
           Breakfast.findOneAndUpdate(
             {},
-            {$set: {steak: 'tofu', eggs: 5, bacon: '3 strips'}},
+            { $set: { steak: 'tofu', eggs: 5, bacon: '3 strips' } },
             updateOptions,
             function(error) {
               assert.ok(!!error);
@@ -1352,7 +1352,7 @@ describe('model: findOneAndUpdate:', function() {
 
               Breakfast.findOneAndUpdate(
                 {},
-                {$set: {steak: 'sirloin', eggs: 6, bacon: 'none'}},
+                { $set: { steak: 'sirloin', eggs: 6, bacon: 'none' } },
                 updateOptions,
                 function(error) {
                   assert.ok(!!error);
@@ -1368,16 +1368,16 @@ describe('model: findOneAndUpdate:', function() {
 
     it('multiple validation errors', function(done) {
       const s = new Schema({
-        steak: {type: String, enum: ['ribeye', 'sirloin']},
-        eggs: {type: Number, min: 4, max: 6},
-        bacon: {type: String, match: /strips/}
+        steak: { type: String, enum: ['ribeye', 'sirloin'] },
+        eggs: { type: Number, min: 4, max: 6 },
+        bacon: { type: String, match: /strips/ }
       });
       const Breakfast = db.model('fam-gh-860-6', s);
 
-      const updateOptions = {runValidators: true, new: true};
+      const updateOptions = { runValidators: true, new: true };
       Breakfast.findOneAndUpdate(
         {},
-        {$set: {steak: 'tofu', eggs: 2, bacon: '3 strips'}},
+        { $set: { steak: 'tofu', eggs: 2, bacon: '3 strips' } },
         updateOptions,
         function(error, breakfast) {
           assert.ok(!!error);
@@ -1391,15 +1391,15 @@ describe('model: findOneAndUpdate:', function() {
 
     it('validators ignore $inc', function(done) {
       const s = new Schema({
-        steak: {type: String, required: true},
-        eggs: {type: Number, min: 4}
+        steak: { type: String, required: true },
+        eggs: { type: Number, min: 4 }
       });
       const Breakfast = db.model('fam-gh-860-7', s);
 
-      const updateOptions = {runValidators: true, upsert: true, new: true};
+      const updateOptions = { runValidators: true, upsert: true, new: true };
       Breakfast.findOneAndUpdate(
         {},
-        {$inc: {eggs: 1}},
+        { $inc: { eggs: 1 } },
         updateOptions,
         function(error, breakfast) {
           assert.ifError(error);
@@ -1421,9 +1421,9 @@ describe('model: findOneAndUpdate:', function() {
       });
 
       const TestModel = db.model('Test', testSchema);
-      TestModel.create({id: '1'}, function(error) {
+      TestModel.create({ id: '1' }, function(error) {
         assert.ifError(error);
-        TestModel.findOneAndUpdate({id: '1'}, {$set: {name: 'Joe'}}, {upsert: true, setDefaultsOnInsert: true},
+        TestModel.findOneAndUpdate({ id: '1' }, { $set: { name: 'Joe' } }, { upsert: true, setDefaultsOnInsert: true },
           function(error) {
             assert.ifError(error);
             done();
@@ -1439,9 +1439,9 @@ describe('model: findOneAndUpdate:', function() {
       });
 
       const TestModel = db.model('Test', testSchema);
-      TestModel.create({blob: null, status: 'active'}, function(error) {
+      TestModel.create({ blob: null, status: 'active' }, function(error) {
         assert.ifError(error);
-        TestModel.findOneAndUpdate({id: '1', blob: null}, {$set: {status: 'inactive'}}, {upsert: true, setDefaultsOnInsert: true},
+        TestModel.findOneAndUpdate({ id: '1', blob: null }, { $set: { status: 'inactive' } }, { upsert: true, setDefaultsOnInsert: true },
           function(error) {
             assert.ifError(error);
             done();
@@ -1463,9 +1463,9 @@ describe('model: findOneAndUpdate:', function() {
       });
 
       const TestModel = db.model('Test', testSchema);
-      TestModel.create({id: '1'}, function(error) {
+      TestModel.create({ id: '1' }, function(error) {
         assert.ifError(error);
-        TestModel.findOneAndUpdate({id: '1'}, {$set: {name: 'Joe'}}, {upsert: true, setDefaultsOnInsert: true},
+        TestModel.findOneAndUpdate({ id: '1' }, { $set: { name: 'Joe' } }, { upsert: true, setDefaultsOnInsert: true },
           function(error) {
             assert.ifError(error);
             done();
@@ -1483,10 +1483,10 @@ describe('model: findOneAndUpdate:', function() {
       });
 
       const TestModel = db.model('Test', testSchema);
-      const update = { $setOnInsert: { a: [{foo: 'bar'}], b: [2] } };
-      const opts = {upsert: true, new: true, setDefaultsOnInsert: true};
+      const update = { $setOnInsert: { a: [{ foo: 'bar' }], b: [2] } };
+      const opts = { upsert: true, new: true, setDefaultsOnInsert: true };
       TestModel
-        .findOneAndUpdate({name: 'abc'}, update, opts,
+        .findOneAndUpdate({ name: 'abc' }, update, opts,
           function(error, doc) {
             assert.ifError(error);
             assert.equal(doc.a.length, 1);
@@ -1518,8 +1518,8 @@ describe('model: findOneAndUpdate:', function() {
         records: []
       }, function(error) {
         assert.ifError(error);
-        Shift.findOneAndUpdate({userId: 'tom'}, {
-          records: [{kind: 'kind1', amount: NaN}]
+        Shift.findOneAndUpdate({ userId: 'tom' }, {
+          records: [{ kind: 'kind1', amount: NaN }]
         }, {
           new: true
         }, function(error) {
@@ -1531,12 +1531,12 @@ describe('model: findOneAndUpdate:', function() {
     });
 
     it('cast errors with nested schemas (gh-3580)', function(done) {
-      const nested = new Schema({num: Number});
-      const s = new Schema({nested: nested});
+      const nested = new Schema({ num: Number });
+      const s = new Schema({ nested: nested });
 
       const MyModel = db.model('Test', s);
 
-      const update = {nested: {num: 'Not a Number'}};
+      const update = { nested: { num: 'Not a Number' } };
       MyModel.findOneAndUpdate({}, update, function(error) {
         assert.ok(error);
         done();
@@ -1544,15 +1544,15 @@ describe('model: findOneAndUpdate:', function() {
     });
 
     it('pull with nested schemas (gh-3616)', function(done) {
-      const nested = new Schema({arr: [{num: Number}]});
-      const s = new Schema({nested: nested});
+      const nested = new Schema({ arr: [{ num: Number }] });
+      const s = new Schema({ nested: nested });
 
       const MyModel = db.model('Test', s);
 
-      MyModel.create({nested: {arr: [{num: 5}]}}, function(error) {
+      MyModel.create({ nested: { arr: [{ num: 5 }] } }, function(error) {
         assert.ifError(error);
-        const update = {$pull: {'nested.arr': {num: 5}}};
-        const options = {new: true};
+        const update = { $pull: { 'nested.arr': { num: 5 } } };
+        const options = { new: true };
         MyModel.findOneAndUpdate({}, update, options, function(error, doc) {
           assert.ifError(error);
           assert.equal(doc.nested.arr.length, 0);
@@ -2133,10 +2133,10 @@ describe('model: findOneAndUpdate:', function() {
 
       const UserSchema = new mongoose.Schema({
         name: String,
-        lastUpdate: {type: Date},
+        lastUpdate: { type: Date },
         friends: [{
           _id: false,
-          status: {type: String, required: true},
+          status: { type: String, required: true },
           id: {
             type: mongoose.Schema.Types.Buffer,
             get: fromUUID,
@@ -2146,7 +2146,7 @@ describe('model: findOneAndUpdate:', function() {
       }, { collection: 'users' });
 
       UserSchema.pre('findOneAndUpdate', function() {
-        this.update({}, { $set: {lastUpdate: new Date()} });
+        this.update({}, { $set: { lastUpdate: new Date() } });
       });
 
       const User = db.model('User', UserSchema);
@@ -2154,15 +2154,15 @@ describe('model: findOneAndUpdate:', function() {
       const friendId = uuid.v4();
       const user = {
         name: 'Sean',
-        friends: [{status: 'New', id: friendId}]
+        friends: [{ status: 'New', id: friendId }]
       };
 
       User.create(user, function(error, user) {
         assert.ifError(error);
 
         const q = { _id: user._id, 'friends.id': friendId };
-        const upd = {'friends.$.status': 'Active'};
-        User.findOneAndUpdate(q, upd, {new: true}).lean().exec(function(error) {
+        const upd = { 'friends.$.status': 'Active' };
+        User.findOneAndUpdate(q, upd, { new: true }).lean().exec(function(error) {
           assert.ifError(error);
           done();
         });
@@ -2252,8 +2252,8 @@ describe('model: findOneAndUpdate:', function() {
     });
 
     it('doesnt do double validation on document arrays during updates (gh-4440)', function(done) {
-      const A = new Schema({str: String});
-      let B = new Schema({a: [A]});
+      const A = new Schema({ str: String });
+      let B = new Schema({ a: [A] });
       let validateCalls = 0;
       B.path('a').validate(function(val) {
         ++validateCalls;
@@ -2264,9 +2264,9 @@ describe('model: findOneAndUpdate:', function() {
       B = db.model('Test', B);
 
       B.findOneAndUpdate(
-        {foo: 'bar'},
-        {$set: {a: [{str: 'asdf'}]}},
-        {runValidators: true},
+        { foo: 'bar' },
+        { $set: { a: [{ str: 'asdf' }] } },
+        { runValidators: true },
         function(err) {
           assert.ifError(err);
           assert.equal(validateCalls, 1); // Assertion error: 1 == 2
@@ -2323,7 +2323,7 @@ describe('model: findOneAndUpdate:', function() {
       return co(function*() {
         const Model = db.model('Test', schema);
         yield Model.findOneAndUpdate({}, {
-          $pull: {someArray: {innerField: '507f191e810c19729de860ea'}}
+          $pull: { someArray: { innerField: '507f191e810c19729de860ea' } }
         }, {
           runValidators: true
         });
@@ -2384,7 +2384,7 @@ describe('model: findOneAndUpdate:', function() {
   it('runs lowercase on $addToSet, $push, etc (gh-4185)', function() {
     const Cat = db.model('Test', {
       _id: String,
-      myArr: { type: [{type: String, lowercase: true}], default: undefined }
+      myArr: { type: [{ type: String, lowercase: true }], default: undefined }
     });
 
     return co(function*() {
diff --git a/test/model.geosearch.test.js b/test/model.geosearch.test.js
index 3848240091f..5363b447d9a 100644
--- a/test/model.geosearch.test.js
+++ b/test/model.geosearch.test.js
@@ -21,7 +21,7 @@ describe('model', function() {
       complex: {},
       type: String
     });
-    schema.index({pos: 'geoHaystack', type: 1}, {bucketSize: 1});
+    schema.index({ pos: 'geoHaystack', type: 1 }, { bucketSize: 1 });
     db = start();
   });
 
@@ -40,10 +40,10 @@ describe('model', function() {
         assert.ifError(err);
 
         const geos = [];
-        geos[0] = new Geo({pos: [10, 10], type: 'place'});
-        geos[1] = new Geo({pos: [15, 5], type: 'place'});
-        geos[2] = new Geo({pos: [20, 15], type: 'house'});
-        geos[3] = new Geo({pos: [1, -1], type: 'house'});
+        geos[0] = new Geo({ pos: [10, 10], type: 'place' });
+        geos[1] = new Geo({ pos: [15, 5], type: 'place' });
+        geos[2] = new Geo({ pos: [20, 15], type: 'house' });
+        geos[3] = new Geo({ pos: [1, -1], type: 'house' });
         let count = geos.length;
 
         for (let i = 0; i < geos.length; i++) {
@@ -54,7 +54,7 @@ describe('model', function() {
         }
 
         function next() {
-          Geo.geoSearch({type: 'place'}, {near: [9, 9], maxDistance: 5}, function(err, results) {
+          Geo.geoSearch({ type: 'place' }, { near: [9, 9], maxDistance: 5 }, function(err, results) {
             assert.ifError(err);
             assert.equal(results.length, 1);
 
@@ -65,7 +65,7 @@ describe('model', function() {
             assert.equal(results[0].id, geos[0].id);
             assert.ok(results[0] instanceof Geo);
 
-            Geo.geoSearch({type: 'place'}, {near: [40, 40], maxDistance: 5}, function(err, results) {
+            Geo.geoSearch({ type: 'place' }, { near: [40, 40], maxDistance: 5 }, function(err, results) {
               assert.ifError(err);
               assert.equal(results.length, 0);
               done();
@@ -82,10 +82,10 @@ describe('model', function() {
         assert.ifError(err);
 
         const geos = [];
-        geos[0] = new Geo({pos: [10, 10], type: 'place'});
-        geos[1] = new Geo({pos: [15, 5], type: 'place'});
-        geos[2] = new Geo({pos: [20, 15], type: 'house'});
-        geos[3] = new Geo({pos: [1, -1], type: 'house'});
+        geos[0] = new Geo({ pos: [10, 10], type: 'place' });
+        geos[1] = new Geo({ pos: [15, 5], type: 'place' });
+        geos[2] = new Geo({ pos: [20, 15], type: 'house' });
+        geos[3] = new Geo({ pos: [1, -1], type: 'house' });
         let count = geos.length;
 
         for (let i = 0; i < geos.length; i++) {
@@ -96,7 +96,7 @@ describe('model', function() {
         }
 
         function next() {
-          Geo.geoSearch({type: 'place'}, {near: [9, 9], maxDistance: 5, lean: true}, function(err, results) {
+          Geo.geoSearch({ type: 'place' }, { near: [9, 9], maxDistance: 5, lean: true }, function(err, results) {
             assert.ifError(err);
             assert.equal(results.length, 1);
 
@@ -119,21 +119,21 @@ describe('model', function() {
       Geo.on('index', function(err) {
         assert.ifError(err);
 
-        const g = new Geo({pos: [10, 10], type: 'place'});
+        const g = new Geo({ pos: [10, 10], type: 'place' });
         g.save(function() {
           Geo.geoSearch([], {}, function(e) {
             assert.ok(e);
             assert.equal(e.message, 'Must pass conditions to geoSearch');
 
-            Geo.geoSearch({type: 'test'}, {}, function(e) {
+            Geo.geoSearch({ type: 'test' }, {}, function(e) {
               assert.ok(e);
               assert.equal(e.message, 'Must specify the near option in geoSearch');
 
-              Geo.geoSearch({type: 'test'}, {near: 'hello'}, function(e) {
+              Geo.geoSearch({ type: 'test' }, { near: 'hello' }, function(e) {
                 assert.ok(e);
                 assert.equal(e.message, 'near option must be an array [x, y]');
 
-                Geo.geoSearch({type: 'test'}, {near: [1, 2]}, function(err) {
+                Geo.geoSearch({ type: 'test' }, { near: [1, 2] }, function(err) {
                   assert.ok(err);
                   assert.ok(/maxDistance needs a number/.test(err));
                   done();
@@ -149,7 +149,7 @@ describe('model', function() {
       const Geo = getModel(db);
 
       Geo.on('index', function() {
-        const prom = Geo.geoSearch({type: 'place'}, {near: [9, 9], maxDistance: 5});
+        const prom = Geo.geoSearch({ type: 'place' }, { near: [9, 9], maxDistance: 5 });
         assert.ok(prom instanceof mongoose.Promise);
 
         prom.then(() => done(), err => done(err));
@@ -160,13 +160,13 @@ describe('model', function() {
       const Geo = getModel(db);
       Geo.on('index', function(err) {
         assert.ifError(err);
-        const g = new Geo({pos: [10, 10], type: 'place'});
+        const g = new Geo({ pos: [10, 10], type: 'place' });
         g.save(function(err) {
           assert.ifError(err);
 
           let promise;
           assert.doesNotThrow(function() {
-            promise = Geo.geoSearch({type: 'place'}, {near: [9, 9], maxDistance: 5});
+            promise = Geo.geoSearch({ type: 'place' }, { near: [9, 9], maxDistance: 5 });
           });
           function validate(ret) {
             assert.equal(ret.length, 1);
diff --git a/test/model.hydrate.test.js b/test/model.hydrate.test.js
index e7f0134d61a..28b55804367 100644
--- a/test/model.hydrate.test.js
+++ b/test/model.hydrate.test.js
@@ -20,14 +20,14 @@ describe('model', function() {
     schemaB = new Schema({
       title: String,
       type: String
-    }, {discriminatorKey: 'type'});
+    }, { discriminatorKey: 'type' });
 
     schemaC = new Schema({
       test: {
         type: String,
         default: 'test'
       }
-    }, {discriminatorKey: 'type'});
+    }, { discriminatorKey: 'type' });
   });
 
   describe('hydrate()', function() {
@@ -39,7 +39,7 @@ describe('model', function() {
 
     before(function() {
       breakfastSchema = new Schema({
-        food: {type: String, enum: ['bacon', 'eggs']}
+        food: { type: String, enum: ['bacon', 'eggs'] }
       });
 
       db = start();
@@ -55,7 +55,7 @@ describe('model', function() {
     });
 
     it('hydrates documents with no modified paths', function(done) {
-      const hydrated = B.hydrate({_id: '541085faedb2f28965d0e8e7', title: 'chair'});
+      const hydrated = B.hydrate({ _id: '541085faedb2f28965d0e8e7', title: 'chair' });
 
       assert.ok(hydrated.get('_id') instanceof DocumentObjectId);
       assert.equal(hydrated.title, 'chair');
@@ -82,7 +82,7 @@ describe('model', function() {
     });
 
     it('works correctly with model discriminators', function(done) {
-      const hydrated = B.hydrate({_id: '541085faedb2f28965d0e8e8', title: 'chair', type: 'C'});
+      const hydrated = B.hydrate({ _id: '541085faedb2f28965d0e8e8', title: 'chair', type: 'C' });
 
       assert.equal(hydrated.test, 'test');
       assert.deepEqual(hydrated.schema.tree, schemaC.tree);
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 3b4f390a9ec..b3c341781d9 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -28,20 +28,20 @@ describe('model', function() {
   describe('indexes', function() {
     it('are created when model is compiled', function(done) {
       const Indexed = new Schema({
-        name: {type: String, index: true},
+        name: { type: String, index: true },
         last: String,
         email: String,
         date: Date
       });
 
-      Indexed.index({last: 1, email: 1}, {unique: true});
-      Indexed.index({date: 1}, {expires: 10});
+      Indexed.index({ last: 1, email: 1 }, { unique: true });
+      Indexed.index({ date: 1 }, { expires: 10 });
 
       const IndexedModel = db.model('IndexedModel1', Indexed, 'indexedmodel' + random());
       let assertions = 0;
 
       IndexedModel.on('index', function() {
-        IndexedModel.collection.getIndexes({full: true}, function(err, indexes) {
+        IndexedModel.collection.getIndexes({ full: true }, function(err, indexes) {
           assert.ifError(err);
 
           indexes.forEach(function(index) {
@@ -66,13 +66,13 @@ describe('model', function() {
 
     it('of embedded documents', function(done) {
       const BlogPosts = new Schema({
-        _id: {type: ObjectId, index: true},
-        title: {type: String, index: true},
+        _id: { type: ObjectId, index: true },
+        title: { type: String, index: true },
         desc: String
       });
 
       const User = new Schema({
-        name: {type: String, index: true},
+        name: { type: String, index: true },
         blogposts: [BlogPosts]
       });
 
@@ -116,7 +116,7 @@ describe('model', function() {
       }, { excludeIndexes: true });
 
       const User = new Schema({
-        name: {type: String, index: true},
+        name: { type: String, index: true },
         blogposts: {
           type: [BlogPost],
           excludeIndexes: true
@@ -145,13 +145,13 @@ describe('model', function() {
 
     it('of multiple embedded documents with same schema', function(done) {
       const BlogPosts = new Schema({
-        _id: {type: ObjectId, unique: true},
-        title: {type: String, index: true},
+        _id: { type: ObjectId, unique: true },
+        title: { type: String, index: true },
         desc: String
       });
 
       const User = new Schema({
-        name: {type: String, index: true},
+        name: { type: String, index: true },
         blogposts: [BlogPosts],
         featured: [BlogPosts]
       });
@@ -197,10 +197,10 @@ describe('model', function() {
         desc: String
       });
 
-      BlogPosts.index({title: 1, desc: 1});
+      BlogPosts.index({ title: 1, desc: 1 });
 
       const User = new Schema({
-        name: {type: String, index: true},
+        name: { type: String, index: true },
         blogposts: [BlogPosts]
       });
 
@@ -270,13 +270,13 @@ describe('model', function() {
     });
 
     it('error should emit on the model', function(done) {
-      const schema = new Schema({name: {type: String}});
+      const schema = new Schema({ name: { type: String } });
       const Test = db.model('IndexError5', schema, 'x' + random());
 
-      Test.create({name: 'hi'}, {name: 'hi'}, function(err) {
+      Test.create({ name: 'hi' }, { name: 'hi' }, function(err) {
         assert.strictEqual(err, null);
-        Test.schema.index({name: 1}, {unique: true});
-        Test.schema.index({other: 1});
+        Test.schema.index({ name: 1 }, { unique: true });
+        Test.schema.index({ other: 1 });
 
         Test.on('index', function(err) {
           assert.ok(/E11000 duplicate key error/.test(err.message), err);
@@ -290,8 +290,8 @@ describe('model', function() {
 
     it('when one index creation errors', function(done) {
       const userSchema = {
-        name: {type: String},
-        secondValue: {type: Boolean}
+        name: { type: String },
+        secondValue: { type: Boolean }
       };
 
       const User = new Schema(userSchema);
@@ -334,7 +334,7 @@ describe('model', function() {
 
     describe('auto creation', function() {
       it('can be disabled', function(done) {
-        const schema = new Schema({name: {type: String, index: true}});
+        const schema = new Schema({ name: { type: String, index: true } });
         schema.set('autoIndex', false);
 
         const Test = db.model('AutoIndexing6', schema, 'autoindexing-disable');
@@ -344,7 +344,7 @@ describe('model', function() {
 
         // Create a doc because mongodb 3.0 getIndexes errors if db doesn't
         // exist
-        Test.create({name: 'Bacon'}, function(err) {
+        Test.create({ name: 'Bacon' }, function(err) {
           assert.ifError(err);
           setTimeout(function() {
             Test.collection.getIndexes(function(err, indexes) {
@@ -359,7 +359,7 @@ describe('model', function() {
 
       describe('global autoIndexes (gh-1875)', function() {
         it('will create indexes as a default', function(done) {
-          const schema = new Schema({name: {type: String, index: true}});
+          const schema = new Schema({ name: { type: String, index: true } });
           const Test = db.model('GlobalAutoIndex7', schema, 'gh-1875-1');
           Test.on('index', function(error) {
             assert.ifError(error);
@@ -373,14 +373,14 @@ describe('model', function() {
         });
 
         it('will not create indexes if the global auto index is false and schema option isnt set (gh-1875)', function(done) {
-          const db = start({config: {autoIndex: false}});
-          const schema = new Schema({name: {type: String, index: true}});
+          const db = start({ config: { autoIndex: false } });
+          const schema = new Schema({ name: { type: String, index: true } });
           const Test = db.model('GlobalAutoIndex8', schema, 'x' + random());
           Test.on('index', function() {
             assert.ok(false, 'Model.ensureIndexes() was called');
           });
 
-          Test.create({name: 'Bacon'}, function(err) {
+          Test.create({ name: 'Bacon' }, function(err) {
             assert.ifError(err);
             setTimeout(function() {
               Test.collection.getIndexes(function(err, indexes) {
@@ -396,14 +396,14 @@ describe('model', function() {
 
     describe.skip('model.ensureIndexes()', function() {
       it('is a function', function(done) {
-        const schema = mongoose.Schema({x: 'string'});
+        const schema = mongoose.Schema({ x: 'string' });
         const Test = mongoose.createConnection().model('ensureIndexes-' + random, schema);
         assert.equal(typeof Test.ensureIndexes, 'function');
         done();
       });
 
       it('returns a Promise', function(done) {
-        const schema = mongoose.Schema({x: 'string'});
+        const schema = mongoose.Schema({ x: 'string' });
         const Test = mongoose.createConnection().model('ensureIndexes-' + random, schema);
         const p = Test.ensureIndexes();
         assert.ok(p instanceof mongoose.Promise);
@@ -411,10 +411,10 @@ describe('model', function() {
       });
 
       it('creates indexes', function(done) {
-        const schema = new Schema({name: {type: String}});
+        const schema = new Schema({ name: { type: String } });
         const Test = db.model('ManualIndexing' + random(), schema, 'x' + random());
 
-        Test.schema.index({name: 1}, {sparse: true});
+        Test.schema.index({ name: 1 }, { sparse: true });
 
         let called = false;
         Test.on('index', function() {
diff --git a/test/model.mapreduce.test.js b/test/model.mapreduce.test.js
index 7b69d8d1ecc..5288dda0d8d 100644
--- a/test/model.mapreduce.test.js
+++ b/test/model.mapreduce.test.js
@@ -64,7 +64,7 @@ describe('model: mapreduce:', function() {
     const num = 10;
     const docs = [];
     for (let i = 0; i < num; ++i) {
-      docs.push({author: authors[i % authors.length], owners: [id], published: true});
+      docs.push({ author: authors[i % authors.length], owners: [id], published: true });
     }
 
     MR.create(docs, function(err, insertedDocs) {
@@ -107,7 +107,7 @@ describe('model: mapreduce:', function() {
           reduce: function(k, vals) {
             return vals.length;
           },
-          query: {author: 'aaron', published: 1, owners: id}
+          query: { author: 'aaron', published: 1, owners: id }
         };
 
         MR.mapReduce(o, function(err, res) {
@@ -128,13 +128,13 @@ describe('model: mapreduce:', function() {
       function modeling() {
         const o = {
           map: function() {
-            emit(this.author, {own: magicID});
+            emit(this.author, { own: magicID });
           },
-          scope: {magicID: magicID},
+          scope: { magicID: magicID },
           reduce: function(k, vals) {
-            return {own: vals[0].own, count: vals.length};
+            return { own: vals[0].own, count: vals.length };
           },
-          out: {replace: '_mapreduce_test_' + random()}
+          out: { replace: '_mapreduce_test_' + random() }
         };
 
         MR.mapReduce(o, function(err, res) {
@@ -146,7 +146,7 @@ describe('model: mapreduce:', function() {
           assert.equal(typeof model.mapReduce, 'function');
 
           // queries work
-          model.where('value.count').gt(1).sort({_id: 1}).exec(function(err, docs) {
+          model.where('value.count').gt(1).sort({ _id: 1 }).exec(function(err, docs) {
             assert.ifError(err);
             assert.equal(docs[0]._id, 'aaron');
             assert.equal(docs[1]._id, 'brian');
@@ -154,7 +154,7 @@ describe('model: mapreduce:', function() {
             assert.equal(docs[3]._id, 'nathan');
 
             // update casting works
-            model.findOneAndUpdate({_id: 'aaron'}, {published: true}, {new: true}, function(err, doc) {
+            model.findOneAndUpdate({ _id: 'aaron' }, { published: true }, { new: true }, function(err, doc) {
               assert.ifError(err);
               assert.ok(doc);
               assert.equal(doc._id, 'aaron');
@@ -162,8 +162,8 @@ describe('model: mapreduce:', function() {
 
               // ad-hoc population works
               model
-                .findOne({_id: 'aaron'})
-                .populate({path: 'value.own', model: 'MapReduce'})
+                .findOne({ _id: 'aaron' })
+                .populate({ path: 'value.own', model: 'MapReduce' })
                 .exec(function(err, doc) {
                   assert.ifError(err);
                   assert.equal(doc.value.own.author, 'guillermo');
@@ -228,7 +228,7 @@ describe('model: mapreduce:', function() {
       const authors = 'aaron guillermo brian nathan'.split(' ');
       const num = 10;
       for (let i = 0; i < num; ++i) {
-        docs.push({author: authors[i % authors.length], owners: [id], published: true});
+        docs.push({ author: authors[i % authors.length], owners: [id], published: true });
       }
 
       MR.create(docs, function(err, insertedDocs) {
@@ -277,13 +277,13 @@ describe('model: mapreduce:', function() {
     it('works with model', function() {
       const o = {
         map: function() {
-          emit(this.author, {own: magicID});
+          emit(this.author, { own: magicID });
         },
-        scope: {magicID: magicID},
+        scope: { magicID: magicID },
         reduce: function(k, vals) {
-          return {own: vals[0].own, count: vals.length};
+          return { own: vals[0].own, count: vals.length };
         },
-        out: {replace: '_mapreduce_test_' + random()}
+        out: { replace: '_mapreduce_test_' + random() }
       };
 
       return MR.mapReduce(o).
@@ -295,7 +295,7 @@ describe('model: mapreduce:', function() {
           assert.equal(typeof ret.mapReduce, 'function');
 
           // queries work
-          return ret.where('value.count').gt(1).sort({_id: 1});
+          return ret.where('value.count').gt(1).sort({ _id: 1 });
         }).
         then(function(docs) {
           assert.equal(docs[0]._id, 'aaron');
diff --git a/test/model.middleware.test.js b/test/model.middleware.test.js
index 84d0abe869e..a3604c7bd18 100644
--- a/test/model.middleware.test.js
+++ b/test/model.middleware.test.js
@@ -53,7 +53,7 @@ describe('model middleware', function() {
 
     const TestMiddleware = db.model('TestPostSaveMiddleware', schema);
 
-    const test = new TestMiddleware({title: 'Little Green Running Hood'});
+    const test = new TestMiddleware({ title: 'Little Green Running Hood' });
 
     test.save(function(err) {
       assert.ifError(err);
@@ -274,8 +274,8 @@ describe('model middleware', function() {
     const parent = new Parent({
       name: 'Han',
       children: [
-        {name: 'Jaina'},
-        {name: 'Jacen'}
+        { name: 'Jaina' },
+        { name: 'Jacen' }
       ]
     });
 
@@ -380,7 +380,7 @@ describe('model middleware', function() {
 
     const Test = db.model('TestPostValidateMiddleware', schema);
 
-    const test = new Test({title: 'banana'});
+    const test = new Test({ title: 'banana' });
 
     test.save(function(err) {
       assert.ifError(err);
diff --git a/test/model.populate.divergent.test.js b/test/model.populate.divergent.test.js
index 49b989231ff..488a633c99c 100644
--- a/test/model.populate.divergent.test.js
+++ b/test/model.populate.divergent.test.js
@@ -32,15 +32,15 @@ describe('model: populate: divergent arrays', function() {
 
   before(function(done) {
     db = start();
-    C = db.model('Child', {_id: Number, name: String}, 'child-' + random());
-    M = db.model('Parent', {array: {type: [{type: Number, ref: 'Child'}]}}, 'parent-' + random());
+    C = db.model('Child', { _id: Number, name: String }, 'child-' + random());
+    M = db.model('Parent', { array: { type: [{ type: Number, ref: 'Child' }] } }, 'parent-' + random());
 
     C.create(
-      {_id: 0, name: 'zero'}
-      , {_id: 1, name: 'one'}
-      , {_id: 2, name: 'two'}, function(err) {
+      { _id: 0, name: 'zero' }
+      , { _id: 1, name: 'one' }
+      , { _id: 2, name: 'two' }, function(err) {
         assert.ifError(err);
-        M.create({array: [0, 1, 2]}, function(err) {
+        M.create({ array: [0, 1, 2] }, function(err) {
           assert.ifError(err);
           done();
         });
@@ -55,7 +55,7 @@ describe('model: populate: divergent arrays', function() {
     it('using $set', function(done) {
       fn(function(err, doc) {
         assert.ifError(err);
-        doc.array.unshift({_id: 10, name: 'ten'});
+        doc.array.unshift({ _id: 10, name: 'ten' });
         doc.save(function(err) {
           check(err);
           done();
@@ -97,52 +97,52 @@ describe('model: populate: divergent arrays', function() {
 
   describe('from match', function() {
     testFails(function(cb) {
-      M.findOne().populate({path: 'array', match: {name: 'one'}}).exec(cb);
+      M.findOne().populate({ path: 'array', match: { name: 'one' } }).exec(cb);
     });
   });
   describe('from skip', function() {
     describe('2', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', options: {skip: 2}}).exec(cb);
+        M.findOne().populate({ path: 'array', options: { skip: 2 } }).exec(cb);
       });
     });
     describe('0', function() {
       testOk(function(cb) {
-        M.findOne().populate({path: 'array', options: {skip: 0}}).exec(cb);
+        M.findOne().populate({ path: 'array', options: { skip: 0 } }).exec(cb);
       });
     });
   });
   describe('from limit', function() {
     describe('0', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', options: {limit: 0}}).exec(cb);
+        M.findOne().populate({ path: 'array', options: { limit: 0 } }).exec(cb);
       });
     });
     describe('1', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', options: {limit: 1}}).exec(cb);
+        M.findOne().populate({ path: 'array', options: { limit: 1 } }).exec(cb);
       });
     });
   });
   describe('from deselected _id', function() {
     describe('using string and only -_id', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', select: '-_id'}).exec(cb);
+        M.findOne().populate({ path: 'array', select: '-_id' }).exec(cb);
       });
     });
     describe('using string', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', select: 'name -_id'}).exec(cb);
+        M.findOne().populate({ path: 'array', select: 'name -_id' }).exec(cb);
       });
     });
     describe('using object and only _id: 0', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', select: {_id: 0}}).exec(cb);
+        M.findOne().populate({ path: 'array', select: { _id: 0 } }).exec(cb);
       });
     });
     describe('using object', function() {
       testFails(function(cb) {
-        M.findOne().populate({path: 'array', select: {_id: 0, name: 1}}).exec(cb);
+        M.findOne().populate({ path: 'array', select: { _id: 0, name: 1 } }).exec(cb);
       });
     });
   });
diff --git a/test/model.populate.setting.test.js b/test/model.populate.setting.test.js
index 4cc41babcfa..514dc5681a4 100644
--- a/test/model.populate.setting.test.js
+++ b/test/model.populate.setting.test.js
@@ -50,13 +50,13 @@ describe('model: populate:', function() {
         before(function(done) {
           const bSchema = new Schema({
             title: String,
-            fans: [{type: id, ref: 'User'}],
-            adhoc: [{subdoc: id, subarray: [{things: [id]}]}],
-            _creator: {type: id, ref: 'User'},
+            fans: [{ type: id, ref: 'User' }],
+            adhoc: [{ subdoc: id, subarray: [{ things: [id] }] }],
+            _creator: { type: id, ref: 'User' },
             embed: [{
-              other: {type: id, ref: 'User'},
-              array: [{type: id, ref: 'User'}],
-              nested: [{subdoc: {type: id, ref: 'User'}}]
+              other: { type: id, ref: 'User' },
+              array: [{ type: id, ref: 'User' }],
+              nested: [{ subdoc: { type: id, ref: 'User' } }]
             }]
           });
 
@@ -85,15 +85,15 @@ describe('model: populate:', function() {
             B.create({
               title: 'Woot',
               fans: [fan1, fan2],
-              adhoc: [{subdoc: fan2, subarray: [{things: [fan1]}]}],
+              adhoc: [{ subdoc: fan2, subarray: [{ things: [fan1] }] }],
               _creator: fan1,
-              embed: [{other: fan1, array: [fan1, fan2]}, {other: fan2, array: [fan2, fan1]}]
+              embed: [{ other: fan1, array: [fan1, fan2] }, { other: fan2, array: [fan2, fan1] }]
             }, {
               title: 'Woot2',
               fans: [fan2, fan1],
-              adhoc: [{subdoc: fan1, subarray: [{things: [fan2]}]}],
+              adhoc: [{ subdoc: fan1, subarray: [{ things: [fan2] }] }],
               _creator: fan2,
-              embed: [{other: fan2, array: [fan2, fan1]}, {other: fan1, array: [fan1, fan2]}]
+              embed: [{ other: fan2, array: [fan2, fan1] }, { other: fan1, array: [fan1, fan2] }]
             }, function(err, post1, post2) {
               assert.ifError(err);
               b1 = post1;
@@ -108,7 +108,7 @@ describe('model: populate:', function() {
         });
 
         function userLiteral(name) {
-          return {_id: construct[id](), name: name};
+          return { _id: construct[id](), name: name };
         }
 
         function user(name) {
@@ -118,8 +118,8 @@ describe('model: populate:', function() {
         it('if a document', function(done) {
           const query = B.findById(b1).
             populate('fans _creator embed.other embed.array embed.nested.subdoc').
-            populate({path: 'adhoc.subdoc', model: 'User'}).
-            populate({path: 'adhoc.subarray.things', model: 'User'});
+            populate({ path: 'adhoc.subdoc', model: 'User' }).
+            populate({ path: 'adhoc.subarray.things', model: 'User' });
           query.exec(function(err, doc) {
             assert.ifError(err);
 
@@ -182,7 +182,7 @@ describe('model: populate:', function() {
             assert.deepEqual(doc.embed[0].other.toObject(), user1b.toObject());
 
             const user1c = user('user2c');
-            doc.embed[0].nested = [{subdoc: user1c}];
+            doc.embed[0].nested = [{ subdoc: user1c }];
             assert.deepEqual(doc.embed[0].nested[0].subdoc.toObject(), user1c.toObject());
 
             // embedded without declared ref in schema
@@ -219,8 +219,8 @@ describe('model: populate:', function() {
         it('if an object', function(done) {
           B.findById(b2)
             .populate('fans _creator embed.other embed.array embed.nested.subdoc')
-            .populate({path: 'adhoc.subdoc', model: 'User'})
-            .populate({path: 'adhoc.subarray.things', model: 'User'})
+            .populate({ path: 'adhoc.subdoc', model: 'User' })
+            .populate({ path: 'adhoc.subarray.things', model: 'User' })
             .exec(function(err, doc) {
               assert.ifError(err);
 
@@ -283,7 +283,7 @@ describe('model: populate:', function() {
 
               name = 'user1c';
               const user1c = userLiteral(name);
-              doc.embed[0].nested = [{subdoc: user1c}];
+              doc.embed[0].nested = [{ subdoc: user1c }];
               assert.equal(doc.embed[0].nested[0].subdoc.name, name);
               const user1cId = doc.embed[0].nested[0].subdoc._id;
 
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 87d85257413..707a764cabf 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -33,10 +33,10 @@ describe('model: populate:', function() {
     userSchema = new Schema({
       name: String,
       email: String,
-      gender: {type: String, enum: ['male', 'female'], default: 'male'},
-      age: {type: Number, default: 21},
-      blogposts: [{type: ObjectId, ref: 'BlogPost'}],
-      followers: [{type: ObjectId, ref: 'User'}]
+      gender: { type: String, enum: ['male', 'female'], default: 'male' },
+      age: { type: Number, default: 21 },
+      blogposts: [{ type: ObjectId, ref: 'BlogPost' }],
+      followers: [{ type: ObjectId, ref: 'User' }]
     });
 
     /**
@@ -44,8 +44,8 @@ describe('model: populate:', function() {
      */
 
     commentSchema = new Schema({
-      asers: [{type: ObjectId, ref: 'User'}],
-      _creator: {type: ObjectId, ref: 'User'},
+      asers: [{ type: ObjectId, ref: 'User' }],
+      _creator: { type: ObjectId, ref: 'User' },
       content: String
     });
 
@@ -54,10 +54,10 @@ describe('model: populate:', function() {
      */
 
     blogPostSchema = new Schema({
-      _creator: {type: ObjectId, ref: 'User'},
+      _creator: { type: ObjectId, ref: 'User' },
       title: String,
       comments: [commentSchema],
-      fans: [{type: ObjectId, ref: 'User'}]
+      fans: [{ type: ObjectId, ref: 'User' }]
     });
 
     db = start();
@@ -75,18 +75,18 @@ describe('model: populate:', function() {
     const BlogPost = db.model('BlogPost', blogPostSchema);
     const User = db.model('User', userSchema);
 
-    User.create({name: 'User 1'}, function(err, user1) {
+    User.create({ name: 'User 1' }, function(err, user1) {
       assert.ifError(err);
 
-      User.create({name: 'User 2'}, function(err, user2) {
+      User.create({ name: 'User 2' }, function(err, user2) {
         assert.ifError(err);
 
         BlogPost.create({
           title: 'Woot',
           _creator: user1._id,
           comments: [
-            {_creator: user1._id, content: 'Woot woot'},
-            {_creator: user2._id, content: 'Wha wha'}
+            { _creator: user1._id, content: 'Woot woot' },
+            { _creator: user2._id, content: 'Wha wha' }
           ]
         }, function(err, post) {
           assert.ifError(err);
@@ -105,13 +105,13 @@ describe('model: populate:', function() {
     const BlogPost = db.model('BlogPost', blogPostSchema);
     const User = db.model('User', userSchema);
 
-    User.create({name: 'User 01'}, function(err, user1) {
+    User.create({ name: 'User 01' }, function(err, user1) {
       assert.ifError(err);
 
-      User.create({name: 'User 02', followers: [user1._id]}, function(err, user2) {
+      User.create({ name: 'User 02', followers: [user1._id] }, function(err, user2) {
         assert.ifError(err);
 
-        User.create({name: 'User 03', followers: [user2._id]}, function(err, user3) {
+        User.create({ name: 'User 03', followers: [user2._id] }, function(err, user3) {
           assert.ifError(err);
 
           BlogPost.create({
@@ -131,11 +131,11 @@ describe('model: populate:', function() {
                   populate: [{
                     path: 'followers',
                     select: 'name followers',
-                    options: {limit: 5},
+                    options: { limit: 5 },
                     populate: { // can also use a single object instead of array of objects
                       path: 'followers',
                       select: 'name',
-                      options: {limit: 2}
+                      options: { limit: 2 }
                     }
                   }]
                 })
@@ -168,24 +168,24 @@ describe('model: populate:', function() {
       // task schema
       const taskSchema = new Schema({
         name: String,
-        handler: {type: Schema.Types.ObjectId, ref: 'Test'}
+        handler: { type: Schema.Types.ObjectId, ref: 'Test' }
       });
 
       // application schema
       const applicationSchema = new Schema({
         name: String,
-        tasks: [{type: Schema.Types.ObjectId, ref: 'Test1'}]
+        tasks: [{ type: Schema.Types.ObjectId, ref: 'Test1' }]
       });
 
       const Handler = db.model('Test', handlerSchema);
       const Task = db.model('Test1', taskSchema);
       const Application = db.model('Test2', applicationSchema);
 
-      Handler.create({name: 'test'}, function(error, doc) {
+      Handler.create({ name: 'test' }, function(error, doc) {
         assert.ifError(error);
-        Task.create({name: 'test2', handler: doc._id}, function(error, doc) {
+        Task.create({ name: 'test2', handler: doc._id }, function(error, doc) {
           assert.ifError(error);
-          const obj = {name: 'test3', tasks: [doc._id]};
+          const obj = { name: 'test3', tasks: [doc._id] };
           Application.create(obj, function(error, doc) {
             assert.ifError(error);
             test(doc._id);
@@ -197,7 +197,7 @@ describe('model: populate:', function() {
         Application.
           findById(id).
           populate([
-            {path: 'tasks', populate: {path: 'handler'}}
+            { path: 'tasks', populate: { path: 'handler' } }
           ]).
           exec(function(error, doc) {
             assert.ifError(error);
@@ -330,12 +330,12 @@ describe('model: populate:', function() {
     const BlogPost = db.model('BlogPost', blogPostSchema);
 
     BlogPost.create(
-      {title: 'woot'},
+      { title: 'woot' },
       function(err, post) {
         assert.ifError(err);
 
         BlogPost.
-          findByIdAndUpdate(post._id, {$set: {_creator: {}}}, function(err) {
+          findByIdAndUpdate(post._id, { $set: { _creator: {} } }, function(err) {
             assert.ok(err);
             done();
           });
@@ -465,14 +465,14 @@ describe('model: populate:', function() {
 
         BlogPost
           .findById(post._id)
-          .populate('_creator', 'email', {name: 'Peanut'})
+          .populate('_creator', 'email', { name: 'Peanut' })
           .exec(function(err, post) {
             assert.ifError(err);
             assert.strictEqual(post._creator, null);
 
             BlogPost
               .findById(post._id)
-              .populate('_creator', 'email', {name: 'Banana'})
+              .populate('_creator', 'email', { name: 'Banana' })
               .exec(function(err, post) {
                 assert.ifError(err);
                 assert.ok(post._creator instanceof User);
@@ -528,7 +528,7 @@ describe('model: populate:', function() {
 
     const userSchema = new mongoose.Schema({
       name: String,
-      company: {type: mongoose.Schema.Types.ObjectId, ref: 'Company'}
+      company: { type: mongoose.Schema.Types.ObjectId, ref: 'Company' }
     });
 
     const sampleSchema = new mongoose.Schema({
@@ -539,9 +539,9 @@ describe('model: populate:', function() {
     const User = db.model('User', userSchema);
     const Sample = db.model('Test', sampleSchema);
 
-    const company = new Company({name: 'Reynholm Industrie'});
-    const user1 = new User({name: 'Douglas', company: company._id});
-    const user2 = new User({name: 'Lambda'});
+    const company = new Company({ name: 'Reynholm Industrie' });
+    const user1 = new User({ name: 'Douglas', company: company._id });
+    const user2 = new User({ name: 'Lambda' });
     const sample = new Sample({
       items: [user1, user2]
     });
@@ -642,7 +642,7 @@ describe('model: populate:', function() {
 
         BlogPost
           .findById(post._id)
-          .populate('_creator', {name: 1})
+          .populate('_creator', { name: 1 })
           .exec(function(err, post) {
             assert.ifError(err);
 
@@ -705,7 +705,7 @@ describe('model: populate:', function() {
             assert.ifError(err);
 
             BlogPost
-              .find({_id: {$in: [post1._id, post2._id]}})
+              .find({ _id: { $in: [post1._id, post2._id] } })
               .populate('fans')
               .exec(function(err, blogposts) {
                 assert.ifError(err);
@@ -767,7 +767,7 @@ describe('model: populate:', function() {
             };
 
             BlogPost
-              .find({$or: [{_id: post1._id}, {_id: post2._id}]})
+              .find({ $or: [{ _id: post1._id }, { _id: post2._id }] })
               .populate('fans')
               .exec(function(err) {
                 assert.ok(err instanceof Error);
@@ -810,7 +810,7 @@ describe('model: populate:', function() {
             assert.ifError(err);
 
             BlogPost
-              .find({_id: {$in: [post1._id, post2._id]}})
+              .find({ _id: { $in: [post1._id, post2._id] } })
               .populate('fans', 'name')
               .exec(function(err, blogposts) {
                 assert.ifError(err);
@@ -871,8 +871,8 @@ describe('model: populate:', function() {
               assert.ifError(err);
 
               BlogPost
-                .find({_id: {$in: [post1._id, post2._id]}})
-                .populate('fans', '', {gender: 'female', _id: {$in: [fan2]}})
+                .find({ _id: { $in: [post1._id, post2._id] } })
+                .populate('fans', '', { gender: 'female', _id: { $in: [fan2] } })
                 .exec(function(err, blogposts) {
                   assert.ifError(err);
 
@@ -887,8 +887,8 @@ describe('model: populate:', function() {
                   assert.equal(blogposts[1].fans[0].email, 'fan2@learnboost.com');
 
                   BlogPost
-                    .find({_id: {$in: [post1._id, post2._id]}})
-                    .populate('fans', false, {gender: 'female'})
+                    .find({ _id: { $in: [post1._id, post2._id] } })
+                    .populate('fans', false, { gender: 'female' })
                     .exec(function(err, blogposts) {
                       assert.ifError(err);
 
@@ -956,8 +956,8 @@ describe('model: populate:', function() {
               assert.ifError(err);
 
               BlogPost
-                .find({_id: {$in: [post1._id, post2._id]}})
-                .populate('fans', undefined, {_id: fan3})
+                .find({ _id: { $in: [post1._id, post2._id] } })
+                .populate('fans', undefined, { _id: fan3 })
                 .exec(function(err, blogposts) {
                   assert.ifError(err);
 
@@ -974,8 +974,8 @@ describe('model: populate:', function() {
                   assert.equal(blogposts[1].fans[0].age, 25);
 
                   BlogPost
-                    .find({_id: {$in: [post1._id, post2._id]}})
-                    .populate('fans', 0, {gender: 'female'})
+                    .find({ _id: { $in: [post1._id, post2._id] } })
+                    .populate('fans', 0, { gender: 'female' })
                     .exec(function(err, blogposts) {
                       assert.ifError(err);
 
@@ -1045,8 +1045,8 @@ describe('model: populate:', function() {
               assert.ifError(err);
 
               BlogPost
-                .find({_id: {$in: [post1._id, post2._id]}})
-                .populate('fans', 'name email', {gender: 'female', age: 25})
+                .find({ _id: { $in: [post1._id, post2._id] } })
+                .populate('fans', 'name email', { gender: 'female', age: 25 })
                 .exec(function(err, blogposts) {
                   assert.ifError(err);
 
@@ -1102,7 +1102,7 @@ describe('model: populate:', function() {
         assert.ifError(err);
 
         BlogPost
-          .find({_id: {$in: [post1._id, post2._id]}})
+          .find({ _id: { $in: [post1._id, post2._id] } })
           .populate('fans', 'name')
           .exec(function(err, blogposts) {
             assert.ifError(err);
@@ -1123,7 +1123,7 @@ describe('model: populate:', function() {
               assert.ifError(err);
 
               BlogPost
-                .findById(blogposts[1]._id, '', {populate: ['fans']})
+                .findById(blogposts[1]._id, '', { populate: ['fans'] })
                 .exec(function(err, post) {
                   assert.ifError(err);
 
@@ -1156,18 +1156,18 @@ describe('model: populate:', function() {
       const BlogPost = db.model('BlogPost', blogPostSchema);
       const User = db.model('User', userSchema);
 
-      User.create({name: 'User 1'}, function(err, user1) {
+      User.create({ name: 'User 1' }, function(err, user1) {
         assert.ifError(err);
 
-        User.create({name: 'User 2'}, function(err, user2) {
+        User.create({ name: 'User 2' }, function(err, user2) {
           assert.ifError(err);
 
           BlogPost.create({
             title: 'Woot',
             _creator: user1._id,
             comments: [
-              {_creator: user1._id, content: 'Woot woot'},
-              {_creator: user2._id, content: 'Wha wha'}
+              { _creator: user1._id, content: 'Woot woot' },
+              { _creator: user2._id, content: 'Wha wha' }
             ]
           }, function(err, post) {
             assert.ifError(err);
@@ -1193,7 +1193,7 @@ describe('model: populate:', function() {
       const BlogPost = db.model('BlogPost', blogPostSchema);
       const User = db.model('User', userSchema);
 
-      User.create({name: 'gh-1055-1'}, {name: 'gh-1055-2'}, function(err, user1, user2) {
+      User.create({ name: 'gh-1055-1' }, { name: 'gh-1055-2' }, function(err, user1, user2) {
         assert.ifError(err);
 
         BlogPost.create({
@@ -1204,15 +1204,15 @@ describe('model: populate:', function() {
           title: 'gh-1055 post2',
           _creator: user1._id,
           comments: [
-            {_creator: user1._id, content: 'Woot woot', asers: []},
-            {_creator: user2._id, content: 'Wha wha', asers: [user1, user2]}
+            { _creator: user1._id, content: 'Woot woot', asers: [] },
+            { _creator: user2._id, content: 'Wha wha', asers: [user1, user2] }
           ]
         }, function(err) {
           assert.ifError(err);
 
           let ran = false;
           BlogPost
-            .find({title: /gh-1055/})
+            .find({ title: /gh-1055/ })
             .sort('title')
             .select('comments')
             .populate('comments._creator')
@@ -1235,7 +1235,7 @@ describe('model: populate:', function() {
     const BlogPost = db.model('BlogPost', blogPostSchema);
     const User = db.model('User', userSchema);
 
-    User.create({name: 'aaron'}, {name: 'val'}, function(err, user1, user2) {
+    User.create({ name: 'aaron' }, { name: 'val' }, function(err, user1, user2) {
       assert.ifError(err);
 
       BlogPost.create(
@@ -1247,7 +1247,7 @@ describe('model: populate:', function() {
         function(err) {
           assert.ifError(err);
           BlogPost.
-            find({title: 'gh-2176'}).
+            find({ title: 'gh-2176' }).
             populate('_creator').
             exec(function(error, posts) {
               assert.ifError(error);
@@ -1288,8 +1288,8 @@ describe('model: populate:', function() {
         BlogPost.create({
           title: 'Woot',
           comments: [
-            {_creator: user1, content: 'Woot woot'},
-            {_creator: user2, content: 'Wha wha'}
+            { _creator: user1, content: 'Woot woot' },
+            { _creator: user2, content: 'Wha wha' }
           ]
         }, function(err, post) {
           assert.ifError(err);
@@ -1331,15 +1331,15 @@ describe('model: populate:', function() {
         BlogPost.create({
           title: 'Woot',
           comments: [
-            {_creator: user1, content: 'Woot woot'},
-            {_creator: user2, content: 'Wha wha'}
+            { _creator: user1, content: 'Woot woot' },
+            { _creator: user2, content: 'Wha wha' }
           ]
         }, function(err, post) {
           assert.ifError(err);
 
           BlogPost
             .findById(post._id)
-            .populate('comments._creator', {email: 1}, {name: /User/})
+            .populate('comments._creator', { email: 1 }, { name: /User/ })
             .exec(function(err, post) {
               assert.ifError(err);
 
@@ -1374,8 +1374,8 @@ describe('model: populate:', function() {
         BlogPost.create({
           title: 'Woot',
           comments: [
-            {_creator: null, content: 'Woot woot'},
-            {_creator: user2, content: 'Wha wha'}
+            { _creator: null, content: 'Woot woot' },
+            { _creator: user2, content: 'Wha wha' }
           ]
         }, function(err, post) {
           assert.ifError(err);
@@ -1389,8 +1389,8 @@ describe('model: populate:', function() {
 
               // add a non-schema property to the document.
               BlogPost.collection.updateOne(
-                {_id: post._id}
-                , {$set: {'comments.0._idontexist': user2._id}}, function(err) {
+                { _id: post._id }
+                , { $set: { 'comments.0._idontexist': user2._id } }, function(err) {
                   assert.ifError(err);
 
                   // allow population of unknown property by passing model name.
@@ -1504,7 +1504,7 @@ describe('model: populate:', function() {
         assert.ifError(err);
 
         BlogPost.
-          find({tags: 'fun'}).
+          find({ tags: 'fun' }).
           lean().
           populate('author').
           exec(function(err, docs) {
@@ -1575,7 +1575,7 @@ describe('model: populate:', function() {
     const User = db.model('User', userSchema);
 
     return co(function*() {
-      const user = new User({name: 'hans zimmer'});
+      const user = new User({ name: 'hans zimmer' });
       yield user.save();
 
       const post = yield BlogPost.create({
@@ -1583,8 +1583,8 @@ describe('model: populate:', function() {
         fans: []
       });
 
-      yield BlogPost.collection.updateOne({_id: post._id}, {
-        $set: {fans: [null, undefined, user.id, null]}
+      yield BlogPost.collection.updateOne({ _id: post._id }, {
+        $set: { fans: [null, undefined, user.id, null] }
       });
 
       const returned = yield BlogPost.
@@ -1601,7 +1601,7 @@ describe('model: populate:', function() {
     const User = db.model('User', userSchema);
 
     return co(function*() {
-      const user = new User({name: 'Victor Hugo'});
+      const user = new User({ name: 'Victor Hugo' });
       yield user.save();
 
       const post = yield BlogPost.create({
@@ -1609,8 +1609,8 @@ describe('model: populate:', function() {
         fans: []
       });
 
-      yield BlogPost.collection.updateOne({_id: post._id}, {
-        $set: {fans: [null, user.id, null, undefined]}
+      yield BlogPost.collection.updateOne({ _id: post._id }, {
+        $set: { fans: [null, user.id, null, undefined] }
       });
 
       const returned = yield BlogPost.
@@ -1629,8 +1629,8 @@ describe('model: populate:', function() {
   it('populating more than one array at a time', function(done) {
     const User = db.model('User', userSchema);
     const M = db.model('Test', new Schema({
-      users: [{type: ObjectId, ref: 'User'}],
-      fans: [{type: ObjectId, ref: 'User'}],
+      users: [{ type: ObjectId, ref: 'User' }],
+      fans: [{ type: ObjectId, ref: 'User' }],
       comments: [commentSchema]
     }));
 
@@ -1649,23 +1649,23 @@ describe('model: populate:', function() {
         users: [fan3],
         fans: [fan1],
         comments: [
-          {_creator: fan1, content: 'bejeah!'},
-          {_creator: fan2, content: 'chickfila'}
+          { _creator: fan1, content: 'bejeah!' },
+          { _creator: fan2, content: 'chickfila' }
         ]
       }, {
         users: [fan1],
         fans: [fan2],
         comments: [
-          {_creator: fan3, content: 'hello'},
-          {_creator: fan1, content: 'world'}
+          { _creator: fan3, content: 'hello' },
+          { _creator: fan1, content: 'world' }
         ]
       }, function(err, post1, post2) {
         assert.ifError(err);
 
         M.where('_id').in([post1, post2])
-          .populate('fans', 'name', {gender: 'female'})
-          .populate('users', 'name', {gender: 'male'})
-          .populate('comments._creator', 'email', {name: null})
+          .populate('fans', 'name', { gender: 'female' })
+          .populate('users', 'name', { gender: 'male' })
+          .populate('comments._creator', 'email', { name: null })
           .exec(function(err, posts) {
             assert.ifError(err);
 
@@ -1703,8 +1703,8 @@ describe('model: populate:', function() {
     const BlogPost = db.model('BlogPost', blogPostSchema);
     const User = db.model('User', userSchema);
     const Inner = new Schema({
-      user: {type: ObjectId, ref: 'User'},
-      post: {type: ObjectId, ref: 'BlogPost'}
+      user: { type: ObjectId, ref: 'User' },
+      post: { type: ObjectId, ref: 'BlogPost' }
     });
     db.model('Test1', Inner);
 
@@ -1731,8 +1731,8 @@ describe('model: populate:', function() {
         assert.ifError(err);
         M.create({
           kids: [
-            {user: fan1, post: post1, y: 5},
-            {user: fan2, post: post2, y: 8}
+            { user: fan1, post: post1, y: 5 },
+            { user: fan2, post: post2, y: 8 }
           ],
           x: 4
         }, function(err, m1) {
@@ -1740,7 +1740,7 @@ describe('model: populate:', function() {
 
           M.findById(m1)
             .populate('kids.user', 'name')
-            .populate('kids.post', 'title', {title: 'woot'})
+            .populate('kids.post', 'title', { title: 'woot' })
             .exec(function(err, o) {
               assert.ifError(err);
               assert.strictEqual(o.kids.length, 2);
@@ -1764,18 +1764,18 @@ describe('model: populate:', function() {
     const User = db.model('User', userSchema);
 
     User.create(
-      {name: 'aaron', age: 10},
-      {name: 'fan2', age: 8},
-      {name: 'someone else', age: 3},
-      {name: 'val', age: 3},
+      { name: 'aaron', age: 10 },
+      { name: 'fan2', age: 8 },
+      { name: 'someone else', age: 3 },
+      { name: 'val', age: 3 },
       function(err, fan1, fan2, fan3, fan4) {
         assert.ifError(err);
 
-        P.create({fans: [fan4, fan2, fan3, fan1]}, function(err, post) {
+        P.create({ fans: [fan4, fan2, fan3, fan1] }, function(err, post) {
           assert.ifError(err);
 
           P.findById(post)
-            .populate('fans', null, null, {sort: {age: 1, name: 1}})
+            .populate('fans', null, null, { sort: { age: 1, name: 1 } })
             .exec(function(err, post) {
               assert.ifError(err);
 
@@ -1786,7 +1786,7 @@ describe('model: populate:', function() {
               assert.equal(post.fans[3].name, 'aaron');
 
               P.findById(post)
-                .populate('fans', 'name', null, {sort: {name: -1}})
+                .populate('fans', 'name', null, { sort: { name: -1 } })
                 .exec(function(err, post) {
                   assert.ifError(err);
 
@@ -1801,7 +1801,7 @@ describe('model: populate:', function() {
                   assert.strictEqual(undefined, post.fans[0].age);
 
                   P.findById(post)
-                    .populate('fans', 'age', {age: {$gt: 3}}, {sort: {name: 'desc'}})
+                    .populate('fans', 'age', { age: { $gt: 3 } }, { sort: { name: 'desc' } })
                     .exec(function(err, post) {
                       assert.ifError(err);
 
@@ -1822,19 +1822,19 @@ describe('model: populate:', function() {
       name: String
     });
     const sJ = new Schema({
-      b: [{type: Schema.Types.ObjectId, ref: 'Test'}]
+      b: [{ type: Schema.Types.ObjectId, ref: 'Test' }]
     });
     const B = db.model('Test', sB);
     const J = db.model('Test1', sJ);
 
-    const b1 = new B({name: 'thing1'});
-    const b2 = new B({name: 'thing2'});
-    const b3 = new B({name: 'thing3'});
-    const b4 = new B({name: 'thing4'});
-    const b5 = new B({name: 'thing5'});
+    const b1 = new B({ name: 'thing1' });
+    const b2 = new B({ name: 'thing2' });
+    const b3 = new B({ name: 'thing3' });
+    const b4 = new B({ name: 'thing4' });
+    const b5 = new B({ name: 'thing5' });
 
-    const j1 = new J({b: [b1.id, b2.id, b5.id]});
-    const j2 = new J({b: [b3.id, b4.id, b5.id]});
+    const j1 = new J({ b: [b1.id, b2.id, b5.id] });
+    const j2 = new J({ b: [b3.id, b4.id, b5.id] });
 
     let count = 7;
 
@@ -1854,7 +1854,7 @@ describe('model: populate:', function() {
     }
 
     function next() {
-      J.find().populate({path: 'b', options: {limit: 2}}).exec(function(err, j) {
+      J.find().populate({ path: 'b', options: { limit: 2 } }).exec(function(err, j) {
         assert.equal(j.length, 2);
         assert.equal(j[0].b.length, 2);
         assert.equal(j[1].b.length, 2);
@@ -1881,19 +1881,19 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: String, ref: 'User'},
+      author: { type: String, ref: 'User' },
       body: String
     });
 
     const User = db.model('User', UserSchema);
     const Note = db.model('Test', NoteSchema);
 
-    const alice = new User({_id: 'alice', name: 'Alice'});
+    const alice = new User({ _id: 'alice', name: 'Alice' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 'alice', body: 'Buy Milk'});
+      const note = new Note({ author: 'alice', body: 'Buy Milk' });
       note.save(function(err) {
         assert.ifError(err);
 
@@ -1915,19 +1915,19 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Number, ref: 'User'},
+      author: { type: Number, ref: 'User' },
       body: String
     });
 
     const User = db.model('User', UserSchema);
     const Note = db.model('Test', NoteSchema);
 
-    const alice = new User({_id: 2359, name: 'Alice'});
+    const alice = new User({ _id: 2359, name: 'Alice' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 2359, body: 'Buy Milk'});
+      const note = new Note({ author: 2359, body: 'Buy Milk' });
       note.save(function(err) {
         assert.ifError(err);
 
@@ -1944,29 +1944,29 @@ describe('model: populate:', function() {
 
   it('required works on ref fields (gh-577)', function(done) {
     const userSchema = new Schema({
-      email: {type: String, required: true}
+      email: { type: String, required: true }
     });
     const User = db.model('User', userSchema);
 
-    const numSchema = new Schema({_id: Number, val: Number});
+    const numSchema = new Schema({ _id: Number, val: Number });
     const Num = db.model('Test', numSchema);
 
-    const strSchema = new Schema({_id: String, val: String});
+    const strSchema = new Schema({ _id: String, val: String });
     const Str = db.model('Test1', strSchema);
 
     const commentSchema = new Schema({
-      user: {type: ObjectId, ref: 'User', required: true},
-      num: {type: Number, ref: 'Test', required: true},
-      str: {type: String, ref: 'Test1', required: true},
+      user: { type: ObjectId, ref: 'User', required: true },
+      num: { type: Number, ref: 'Test', required: true },
+      str: { type: String, ref: 'Test1', required: true },
       text: String
     });
     const Comment = db.model('Comment', commentSchema);
 
     let pending = 3;
 
-    const string = new Str({_id: 'my string', val: 'hello'});
-    const number = new Num({_id: 1995, val: 234});
-    const user = new User({email: 'test'});
+    const string = new Str({ _id: 'my string', val: 'hello' });
+    const number = new Num({ _id: 1995, val: 234 });
+    const user = new User({ email: 'test' });
 
     string.save(next);
     number.save(next);
@@ -2007,7 +2007,7 @@ describe('model: populate:', function() {
             .exec(function(err, comment) {
               assert.ifError(err);
 
-              comment.set({text: 'test2'});
+              comment.set({ text: 'test2' });
 
               comment.save(function(err) {
                 assert.ifError(err);
@@ -2020,20 +2020,20 @@ describe('model: populate:', function() {
   });
 
   it('populate works with schemas with both id and _id defined', function(done) {
-    const S1 = new Schema({id: String});
-    const S2 = new Schema({things: [{type: ObjectId, ref: 'Test'}]});
+    const S1 = new Schema({ id: String });
+    const S2 = new Schema({ things: [{ type: ObjectId, ref: 'Test' }] });
 
     const M1 = db.model('Test', S1);
     const M2 = db.model('Test1', S2);
-    db.model('Test2', Schema({_id: String, val: String}));
+    db.model('Test2', Schema({ _id: String, val: String }));
 
     M1.create(
-      {id: 'The Tiger That Isn\'t'}
-      , {id: 'Users Guide To The Universe'}
+      { id: 'The Tiger That Isn\'t' }
+      , { id: 'Users Guide To The Universe' }
       , function(err, a, b) {
         assert.ifError(err);
 
-        const m2 = new M2({things: [a, b]});
+        const m2 = new M2({ things: [a, b] });
         m2.save(function(err) {
           assert.ifError(err);
           M2.findById(m2).populate('things').exec(function(err, doc) {
@@ -2051,7 +2051,7 @@ describe('model: populate:', function() {
     const BlogPost = db.model('BlogPost', blogPostSchema);
     const User = db.model('User', userSchema);
 
-    User.create({name: 'aphex'}, {name: 'twin'}, function(err, u1, u2) {
+    User.create({ name: 'aphex' }, { name: 'twin' }, function(err, u1, u2) {
       assert.ifError(err);
 
       BlogPost.create({
@@ -2060,8 +2060,8 @@ describe('model: populate:', function() {
       }, function(err, post) {
         assert.ifError(err);
 
-        const update = {fans: [u1, u2]};
-        BlogPost.updateOne({_id: post}, update, function(err) {
+        const update = { fans: [u1, u2] };
+        BlogPost.updateOne({ _id: post }, update, function(err) {
           assert.ifError(err);
 
           // the original update doc should not be modified
@@ -2134,19 +2134,19 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Buffer, ref: 'User'},
+      author: { type: Buffer, ref: 'User' },
       body: String
     });
 
     const User = db.model('User', UserSchema);
     const Note = db.model('Test', NoteSchema);
 
-    const alice = new User({_id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice'});
+    const alice = new User({ _id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 'alice', body: 'Buy Milk'});
+      const note = new Note({ author: 'alice', body: 'Buy Milk' });
       note.save(function(err) {
         assert.ifError(err);
 
@@ -2168,19 +2168,19 @@ describe('model: populate:', function() {
     });
 
     const NoteSchema = new Schema({
-      author: {type: Buffer, ref: 'User', required: true},
+      author: { type: Buffer, ref: 'User', required: true },
       body: String
     });
 
     const User = db.model('User', UserSchema);
     const Note = db.model('Test', NoteSchema);
 
-    const alice = new User({_id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice'});
+    const alice = new User({ _id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice' });
 
     alice.save(function(err) {
       assert.ifError(err);
 
-      const note = new Note({author: 'alice', body: 'Buy Milk'});
+      const note = new Note({ author: 'alice', body: 'Buy Milk' });
       note.save(function(err) {
         assert.ifError(err);
 
@@ -2229,17 +2229,17 @@ describe('model: populate:', function() {
 
   describe('specifying a custom model without specifying a ref in schema', function() {
     it('with String _id', function(done) {
-      const A = db.model('Test', {name: String, _id: String});
-      const B = db.model('Test1', {other: String});
-      A.create({name: 'hello', _id: 'first'}, function(err, a) {
+      const A = db.model('Test', { name: String, _id: String });
+      const B = db.model('Test1', { other: String });
+      A.create({ name: 'hello', _id: 'first' }, function(err, a) {
         if (err) {
           return done(err);
         }
-        B.create({other: a._id}, function(err, b) {
+        B.create({ other: a._id }, function(err, b) {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
+          B.findById(b._id).populate({ path: 'other', model: 'Test' }).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2250,17 +2250,17 @@ describe('model: populate:', function() {
       });
     });
     it('with Number _id', function(done) {
-      const A = db.model('Test', {name: String, _id: Number});
-      const B = db.model('Test1', {other: Number});
-      A.create({name: 'hello', _id: 3}, function(err, a) {
+      const A = db.model('Test', { name: String, _id: Number });
+      const B = db.model('Test1', { other: Number });
+      A.create({ name: 'hello', _id: 3 }, function(err, a) {
         if (err) {
           return done(err);
         }
-        B.create({other: a._id}, function(err, b) {
+        B.create({ other: a._id }, function(err, b) {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
+          B.findById(b._id).populate({ path: 'other', model: 'Test' }).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2271,17 +2271,17 @@ describe('model: populate:', function() {
       });
     });
     it('with Buffer _id', function(done) {
-      const A = db.model('Test', {name: String, _id: Buffer});
-      const B = db.model('Test1', {other: Buffer});
-      A.create({name: 'hello', _id: Buffer.from('x')}, function(err, a) {
+      const A = db.model('Test', { name: String, _id: Buffer });
+      const B = db.model('Test1', { other: Buffer });
+      A.create({ name: 'hello', _id: Buffer.from('x') }, function(err, a) {
         if (err) {
           return done(err);
         }
-        B.create({other: a._id}, function(err, b) {
+        B.create({ other: a._id }, function(err, b) {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
+          B.findById(b._id).populate({ path: 'other', model: 'Test' }).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2292,17 +2292,17 @@ describe('model: populate:', function() {
       });
     });
     it('with ObjectId _id', function(done) {
-      const A = db.model('Test', {name: String});
-      const B = db.model('Test1', {other: Schema.ObjectId});
-      A.create({name: 'hello'}, function(err, a) {
+      const A = db.model('Test', { name: String });
+      const B = db.model('Test1', { other: Schema.ObjectId });
+      A.create({ name: 'hello' }, function(err, a) {
         if (err) {
           return done(err);
         }
-        B.create({other: a._id}, function(err, b) {
+        B.create({ other: a._id }, function(err, b) {
           if (err) {
             return done(err);
           }
-          B.findById(b._id).populate({path: 'other', model: 'Test'}).exec(function(err, b) {
+          B.findById(b._id).populate({ path: 'other', model: 'Test' }).exec(function(err, b) {
             if (err) {
               return done(err);
             }
@@ -2342,8 +2342,8 @@ describe('model: populate:', function() {
           path: 'fans',
           select: 'name',
           model: 'Test',
-          match: {name: /u/},
-          options: {sort: {name: -1}}
+          match: { name: /u/ },
+          options: { sort: { name: -1 } }
         })
         .exec(function(err, post) {
           assert.ifError(err);
@@ -2417,7 +2417,7 @@ describe('model: populate:', function() {
 
     it('of individual document works', function(done) {
       B.findById(post1._id, function(error, post1) {
-        const ret = utils.populate({path: '_creator', model: User});
+        const ret = utils.populate({ path: '_creator', model: User });
         B.populate(post1, ret, function(err, post) {
           assert.ifError(err);
           assert.ok(post);
@@ -2436,7 +2436,7 @@ describe('model: populate:', function() {
 
           B.findById(post1._id, function(err, doc) {
             assert.ifError(err);
-            B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
+            B.populate(doc, [{ path: '_creator', model: 'User' }, { path: 'fans', model: 'User' }], function(err, post) {
               assert.ifError(err);
               assert.ok(post);
               assert.ok(post._creator instanceof User);
@@ -2448,7 +2448,7 @@ describe('model: populate:', function() {
               assert.equal(String(post._creator._id), String(post.populated('_creator')));
               assert.ok(Array.isArray(post.populated('fans')));
 
-              B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
+              B.populate(doc, [{ path: '_creator', model: 'User' }, { path: 'fans', model: 'User' }], function(err, post) {
                 assert.ifError(err);
                 assert.ok(post);
                 assert.ok(post._creator instanceof User);
@@ -2473,7 +2473,7 @@ describe('model: populate:', function() {
 
           B.findById(post1._id, function(err, doc) {
             assert.ifError(err);
-            B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
+            B.populate(doc, [{ path: '_creator', model: 'User' }, { path: 'fans', model: 'User' }], function(err, post) {
               assert.ifError(err);
               assert.ok(post);
               assert.ok(post._creator instanceof User);
@@ -2489,7 +2489,7 @@ describe('model: populate:', function() {
               doc.markModified('_creator');
               doc.markModified('fans');
 
-              B.populate(doc, [{path: '_creator', model: 'User'}, {path: 'fans', model: 'User'}], function(err, post) {
+              B.populate(doc, [{ path: '_creator', model: 'User' }, { path: 'fans', model: 'User' }], function(err, post) {
                 assert.ifError(err);
                 assert.ok(post);
                 assert.ok(post._creator instanceof User);
@@ -2520,7 +2520,7 @@ describe('model: populate:', function() {
           assert.ifError(error);
           B.findById(post2._id, function(error, post2) {
             assert.ifError(error);
-            const ret = utils.populate({path: '_creator', model: 'User'});
+            const ret = utils.populate({ path: '_creator', model: 'User' });
             B.populate([post1, post2], ret, function(err, posts) {
               assert.ifError(err);
               assert.ok(posts);
@@ -2596,7 +2596,7 @@ describe('model: populate:', function() {
           assert.ifError(err);
 
           BlogPost
-            .find({_id: {$in: [post1._id, post2._id]}})
+            .find({ _id: { $in: [post1._id, post2._id] } })
             .populate('fans')
             .lean()
             .exec(function(err, blogposts) {
@@ -2706,18 +2706,18 @@ describe('model: populate:', function() {
       db.deleteModel(/User/);
       U = db.model('User', Schema({
         name: 'string',
-        comments: [{type: Schema.ObjectId, ref: 'Comment'}],
-        comment: {type: Schema.ObjectId, ref: 'Comment'}
+        comments: [{ type: Schema.ObjectId, ref: 'Comment' }],
+        comment: { type: Schema.ObjectId, ref: 'Comment' }
       }));
 
-      C.create({body: 'comment 1', title: '1'}, {body: 'comment 2', title: 2}, function(err, c1_, c2_) {
+      C.create({ body: 'comment 1', title: '1' }, { body: 'comment 2', title: 2 }, function(err, c1_, c2_) {
         assert.ifError(err);
         c1 = c1_;
         c2 = c2_;
 
         U.create(
-          {name: 'u1', comments: [c1, c2], comment: c1}
-          , {name: 'u2', comment: c2}
+          { name: 'u1', comments: [c1, c2], comment: c1 }
+          , { name: 'u2', comment: c2 }
           , function(err) {
             assert.ifError(err);
             done();
@@ -2727,7 +2727,7 @@ describe('model: populate:', function() {
 
     describe('in a subdocument', function() {
       it('works', function(done) {
-        U.find({name: 'u1'}).populate('comments', {_id: 0}).exec(function(err, docs) {
+        U.find({ name: 'u1' }).populate('comments', { _id: 0 }).exec(function(err, docs) {
           assert.ifError(err);
 
           const doc = docs[0];
@@ -2740,7 +2740,7 @@ describe('model: populate:', function() {
             assert.equal(typeof d._doc.__v, 'number');
           });
 
-          U.findOne({name: 'u1'}).populate('comments', 'title -_id').exec(function(err, doc) {
+          U.findOne({ name: 'u1' }).populate('comments', 'title -_id').exec(function(err, doc) {
             assert.ifError(err);
             assert.equal(doc.comments.length, 2);
             doc.comments.forEach(function(d) {
@@ -2750,7 +2750,7 @@ describe('model: populate:', function() {
               assert.equal(d.body, undefined);
               assert.equal(typeof d._doc.__v, 'undefined');
             });
-            U.findOne({name: 'u1'}).populate('comments', '-_id').exec(function(err, doc) {
+            U.findOne({ name: 'u1' }).populate('comments', '-_id').exec(function(err, doc) {
               assert.ifError(err);
               assert.equal(doc.comments.length, 2);
               doc.comments.forEach(function(d) {
@@ -2767,7 +2767,7 @@ describe('model: populate:', function() {
       });
 
       it('with lean', function(done) {
-        U.find({name: 'u1'}).lean().populate({path: 'comments', select: {_id: 0}, options: {lean: true}}).exec(function(err, docs) {
+        U.find({ name: 'u1' }).lean().populate({ path: 'comments', select: { _id: 0 }, options: { lean: true } }).exec(function(err, docs) {
           assert.ifError(err);
 
           const doc = docs[0];
@@ -2778,7 +2778,7 @@ describe('model: populate:', function() {
             assert.equal(typeof d.__v, 'number');
           });
 
-          U.findOne({name: 'u1'}).lean().populate('comments', '-_id', null, {lean: true}).exec(function(err, doc) {
+          U.findOne({ name: 'u1' }).lean().populate('comments', '-_id', null, { lean: true }).exec(function(err, doc) {
             assert.ifError(err);
             assert.equal(doc.comments.length, 2);
             doc.comments.forEach(function(d) {
@@ -2796,7 +2796,7 @@ describe('model: populate:', function() {
       it('still works (gh-1441)', function(done) {
         U.find()
           .select('-_id comment name')
-          .populate('comment', {_id: 0}).exec(function(err, docs) {
+          .populate('comment', { _id: 0 }).exec(function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
 
@@ -2863,16 +2863,16 @@ describe('model: populate:', function() {
       const review = {
         _id: 0,
         text: 'Test',
-        item: {id: 1, type: 'Test1'},
-        items: [{id: 1, type: 'Test1'}, {id: 2, type: 'Test2'}]
+        item: { id: 1, type: 'Test1' },
+        items: [{ id: 1, type: 'Test1' }, { id: 2, type: 'Test2' }]
       };
 
       return co(function*() {
         yield Item1.deleteMany({});
         yield Item2.deleteMany({});
 
-        yield Item1.create({_id: 1, name: 'Val'});
-        yield Item2.create({_id: 2, otherName: 'Val'});
+        yield Item1.create({ _id: 1, name: 'Val' });
+        yield Item2.create({ _id: 2, otherName: 'Val' });
         yield Review.create(review);
       });
     });
@@ -2920,7 +2920,7 @@ describe('model: populate:', function() {
       });
       const Basket = db.model('Test2', basketSchema);
 
-      new Baseball({seam: 'yarn'}).
+      new Baseball({ seam: 'yarn' }).
         save().
         then(function(baseball) {
           return new Basket({
@@ -3304,13 +3304,13 @@ describe('model: populate:', function() {
 
     beforeEach(function() {
       db.deleteModel(/Test/);
-      Cat = db.model('Cat', new Schema({name: String}));
-      const litterSchema = new Schema({name: String, cats: {}, o: {}, a: []});
+      Cat = db.model('Cat', new Schema({ name: String }));
+      const litterSchema = new Schema({ name: String, cats: {}, o: {}, a: [] });
       Litter = db.model('Test', litterSchema);
     });
 
     it('when saving new docs', function(done) {
-      Cat.create({name: 'new1'}, {name: 'new2'}, {name: 'new3'}, function(err, a, b, c) {
+      Cat.create({ name: 'new1' }, { name: 'new2' }, { name: 'new3' }, function(err, a, b, c) {
         if (err) {
           return done(err);
         }
@@ -3325,12 +3325,12 @@ describe('model: populate:', function() {
     });
 
     it('when saving existing docs 5T5', function(done) {
-      Cat.create({name: 'ex1'}, {name: 'ex2'}, {name: 'ex3'}, function(err, a, b, c) {
+      Cat.create({ name: 'ex1' }, { name: 'ex2' }, { name: 'ex3' }, function(err, a, b, c) {
         if (err) {
           return done(err);
         }
 
-        Litter.create({name: 'existing'}, function(err, doc) {
+        Litter.create({ name: 'existing' }, function(err, doc) {
           doc.cats = [a];
           doc.o = b;
           doc.a = [c];
@@ -3404,7 +3404,7 @@ describe('model: populate:', function() {
       const BlogPost = db.model('BlogPost', new Schema({
         title: String,
         user: { type: ObjectId, ref: 'User' },
-        fans: [{ type: ObjectId}]
+        fans: [{ type: ObjectId }]
       }));
       const User = db.model('User', new Schema({ name: String }));
 
@@ -3433,7 +3433,7 @@ describe('model: populate:', function() {
     it('maps results back to correct document (gh-1444)', function(done) {
       const articleSchema = new Schema({
         body: String,
-        mediaAttach: {type: Schema.ObjectId, ref: 'Test'},
+        mediaAttach: { type: Schema.ObjectId, ref: 'Test' },
         author: String
       });
       const Article = db.model('Article', articleSchema);
@@ -3443,13 +3443,13 @@ describe('model: populate:', function() {
       });
       const Media = db.model('Test', mediaSchema);
 
-      Media.create({filename: 'one'}, function(err, media) {
+      Media.create({ filename: 'one' }, function(err, media) {
         assert.ifError(err);
 
         Article.create(
-          {body: 'body1', author: 'a'}
-          , {body: 'body2', author: 'a', mediaAttach: media._id}
-          , {body: 'body3', author: 'a'}, function(err) {
+          { body: 'body1', author: 'a' }
+          , { body: 'body2', author: 'a', mediaAttach: media._id }
+          , { body: 'body3', author: 'a' }, function(err) {
             if (err) {
               return done(err);
             }
@@ -3470,7 +3470,7 @@ describe('model: populate:', function() {
 
     it('handles skip', function(done) {
       const movieSchema = new Schema({});
-      const categorySchema = new Schema({movies: [{type: ObjectId, ref: 'Movie'}]});
+      const categorySchema = new Schema({ movies: [{ type: ObjectId, ref: 'Movie' }] });
 
       const Movie = db.model('Movie', movieSchema);
       const Category = db.model('Category', categorySchema);
@@ -3480,9 +3480,9 @@ describe('model: populate:', function() {
         Movie.find({}, function(error, docs) {
           assert.ifError(error);
           assert.equal(docs.length, 3);
-          Category.create({movies: [docs[0]._id, docs[1]._id, docs[2]._id]}, function(error) {
+          Category.create({ movies: [docs[0]._id, docs[1]._id, docs[2]._id] }, function(error) {
             assert.ifError(error);
-            Category.findOne({}).populate({path: 'movies', options: {limit: 2, skip: 1}}).exec(function(error, category) {
+            Category.findOne({}).populate({ path: 'movies', options: { limit: 2, skip: 1 } }).exec(function(error, category) {
               assert.ifError(error);
               assert.equal(category.movies.length, 2);
               done();
@@ -3493,21 +3493,21 @@ describe('model: populate:', function() {
     });
 
     it('handles slice (gh-1934)', function(done) {
-      const movieSchema = new Schema({title: String, actors: [String]});
-      const categorySchema = new Schema({movies: [{type: ObjectId, ref: 'Movie'}]});
+      const movieSchema = new Schema({ title: String, actors: [String] });
+      const categorySchema = new Schema({ movies: [{ type: ObjectId, ref: 'Movie' }] });
 
       const Movie = db.model('Movie', movieSchema);
       const Category = db.model('Category', categorySchema);
       const movies = [
-        {title: 'Rush', actors: ['Chris Hemsworth', 'Daniel Bruhl']},
-        {title: 'Pacific Rim', actors: ['Charlie Hunnam', 'Idris Elba']},
-        {title: 'Man of Steel', actors: ['Henry Cavill', 'Amy Adams']}
+        { title: 'Rush', actors: ['Chris Hemsworth', 'Daniel Bruhl'] },
+        { title: 'Pacific Rim', actors: ['Charlie Hunnam', 'Idris Elba'] },
+        { title: 'Man of Steel', actors: ['Henry Cavill', 'Amy Adams'] }
       ];
       Movie.create(movies[0], movies[1], movies[2], function(error, m1, m2, m3) {
         assert.ifError(error);
-        Category.create({movies: [m1._id, m2._id, m3._id]}, function(error) {
+        Category.create({ movies: [m1._id, m2._id, m3._id] }, function(error) {
           assert.ifError(error);
-          Category.findOne({}).populate({path: 'movies', options: {slice: {actors: 1}}}).exec(function(error, category) {
+          Category.findOne({}).populate({ path: 'movies', options: { slice: { actors: 1 } } }).exec(function(error, category) {
             assert.ifError(error);
             assert.equal(category.movies.length, 3);
             assert.equal(category.movies[0].actors.length, 1);
@@ -3567,7 +3567,7 @@ describe('model: populate:', function() {
     it('handles toObject() (gh-3279)', function(done) {
       const teamSchema = new Schema({
         members: [{
-          user: {type: ObjectId, ref: 'User'},
+          user: { type: ObjectId, ref: 'User' },
           role: String
         }]
       });
@@ -3595,11 +3595,11 @@ describe('model: populate:', function() {
 
       const User = db.model('User', userSchema);
 
-      const user = new User({username: 'Test'});
+      const user = new User({ username: 'Test' });
 
       user.save(function(err) {
         assert.ifError(err);
-        const team = new Team({members: [{user: user}]});
+        const team = new Team({ members: [{ user: user }] });
 
         team.save(function(err) {
           assert.ifError(err);
@@ -3613,23 +3613,23 @@ describe('model: populate:', function() {
     });
 
     it('populate option (gh-2321)', function(done) {
-      const User = db.model('User', {name: String});
+      const User = db.model('User', { name: String });
       const Group = db.model('Group', {
-        users: [{type: mongoose.Schema.Types.ObjectId, ref: 'User'}],
+        users: [{ type: mongoose.Schema.Types.ObjectId, ref: 'User' }],
         name: String
       });
 
-      User.create({name: 'Val'}, function(error, user) {
+      User.create({ name: 'Val' }, function(error, user) {
         assert.ifError(error);
-        Group.create({users: [user._id], name: 'test'}, function(error, group) {
+        Group.create({ users: [user._id], name: 'test' }, function(error, group) {
           assert.ifError(error);
           test(group._id);
         });
       });
 
       const test = function(id) {
-        const options = {populate: {path: 'users', model: 'User'}};
-        Group.find({_id: id}, '-name', options, function(error, group) {
+        const options = { populate: { path: 'users', model: 'User' } };
+        Group.find({ _id: id }, '-name', options, function(error, group) {
           assert.ifError(error);
           assert.ok(group[0].users[0]._id);
           done();
@@ -5274,8 +5274,8 @@ describe('model: populate:', function() {
           localField: 'activity.cluster',
           foreignField: 'clusters'
         });
-        DocSchema.set('toObject', {virtuals: true});
-        DocSchema.set('toJSON', {virtuals: true});
+        DocSchema.set('toObject', { virtuals: true });
+        DocSchema.set('toJSON', { virtuals: true });
         const Doc = db.model('Test2', DocSchema);
 
         Cluster.create([{ name: 'c1' }, { name: 'c2' }, { name: 'c3' }]).
@@ -5980,9 +5980,9 @@ describe('model: populate:', function() {
 
       it('empty virtual with Model.populate (gh-5331)', function(done) {
         const myModelSchema = new Schema({
-          virtualRefKey: {type: String, ref: 'gh5331'}
+          virtualRefKey: { type: String, ref: 'gh5331' }
         });
-        myModelSchema.set('toJSON', {virtuals: true});
+        myModelSchema.set('toJSON', { virtuals: true });
         myModelSchema.virtual('populatedVirtualRef', {
           ref: 'gh5331',
           localField: 'virtualRefKey',
@@ -6085,7 +6085,7 @@ describe('model: populate:', function() {
 
       it('array underneath non-existent array (gh-6245)', function() {
         return co(function*() {
-          let DepartmentSchema = new Schema({name: String});
+          let DepartmentSchema = new Schema({ name: String });
           let CompanySchema = new Schema({
             name: String,
             departments: [DepartmentSchema]
@@ -6094,12 +6094,12 @@ describe('model: populate:', function() {
           let Company = db.model('gh6245', CompanySchema);
           const company = new Company({
             name: 'Uber',
-            departments: [{name: 'Security'}, {name: 'Engineering'}]
+            departments: [{ name: 'Security' }, { name: 'Engineering' }]
           });
 
           yield company.save();
 
-          const EmployeeSchema = new Schema({name: String});
+          const EmployeeSchema = new Schema({ name: String });
           DepartmentSchema = new Schema({
             name: String,
             employees: [{ type: mongoose.Schema.Types.ObjectId, ref: 'gh6245' }]
@@ -6151,7 +6151,7 @@ describe('model: populate:', function() {
         });
         const Person = db.model('gh5336_0', PersonSchema);
 
-        const band = new Band({name: 'The Beatles', active: false});
+        const band = new Band({ name: 'The Beatles', active: false });
         const person = new Person({
           name: 'George Harrison',
           bands: ['The Beatles']
@@ -6197,7 +6197,7 @@ describe('model: populate:', function() {
         });
         const Person = db.model('gh5336_11', PersonSchema);
 
-        const band = new Band({name: 'The Beatles', active: false});
+        const band = new Band({ name: 'The Beatles', active: false });
         const person = new Person({
           name: 'George Harrison',
           bands: ['The Beatles']
@@ -6462,7 +6462,7 @@ describe('model: populate:', function() {
             type: String,
             required: true
           }
-        }, {discriminatorKey: 'type'});
+        }, { discriminatorKey: 'type' });
 
         const ItemBookSchema = new mongoose.Schema({
           author: {
@@ -6497,11 +6497,11 @@ describe('model: populate:', function() {
 
         const Bundle = db.model('Test', BundleSchema);
 
-        return Author.create({firstName: 'David', lastName: 'Flanagan'}).
+        return Author.create({ firstName: 'David', lastName: 'Flanagan' }).
           then(function(author) {
             return Bundle.create({
               name: 'Javascript Book Collection', items: [
-                {type: 'Book', title: 'JavaScript: The Definitive Guide', author: author},
+                { type: 'Book', title: 'JavaScript: The Definitive Guide', author: author },
                 {
                   type: 'EBook',
                   title: 'JavaScript: The Definitive Guide Ebook',
@@ -6571,7 +6571,7 @@ describe('model: populate:', function() {
         // Generate Embedded Discriminators
         const eventSchema = new Schema(
           { message: String },
-          { discriminatorKey: 'kind'}
+          { discriminatorKey: 'kind' }
         );
 
         const batchSchema = new Schema({ events: [eventSchema] });
@@ -6584,8 +6584,8 @@ describe('model: populate:', function() {
             users: [Number]
           },
           {
-            toJSON: { virtuals: true},
-            toObject: { virtuals: true}
+            toJSON: { virtuals: true },
+            toObject: { virtuals: true }
           }
         );
 
@@ -7466,17 +7466,17 @@ describe('model: populate:', function() {
 
   it('populate child with same name as parent (gh-6839) (gh-6908)', function() {
     const parentFieldsToPopulate = [
-      {path: 'children.child'},
-      {path: 'child'}
+      { path: 'children.child' },
+      { path: 'child' }
     ];
 
     const childSchema = new mongoose.Schema({ name: String });
     const Child = db.model('Child', childSchema);
 
     const parentSchema = new mongoose.Schema({
-      child: {type: mongoose.Schema.Types.ObjectId, ref: 'Child'},
+      child: { type: mongoose.Schema.Types.ObjectId, ref: 'Child' },
       children: [{
-        child: {type: mongoose.Schema.Types.ObjectId, ref: 'Child' }
+        child: { type: mongoose.Schema.Types.ObjectId, ref: 'Child' }
       }]
     });
     const Parent = db.model('Parent', parentSchema);
@@ -7605,7 +7605,7 @@ describe('model: populate:', function() {
     const Post = db.model('Post', postSchema);
 
     const authors = '123'.split('').map(n => {
-      return new Author({ name: `author${n}`});
+      return new Author({ name: `author${n}` });
     });
 
     const comments = 'abc'.split('').map((l, i) => {
@@ -7703,7 +7703,7 @@ describe('model: populate:', function() {
     const Comment = db.model('Comment', commentSchema);
 
     return co(function*() {
-      const post = yield Post.create({ name: 'n1'});
+      const post = yield Post.create({ name: 'n1' });
       const comment = yield Comment.create({ postId: post._id });
 
       const doc = yield Post.findOne({}).populate('comments').lean();
@@ -7734,7 +7734,7 @@ describe('model: populate:', function() {
     const Comment = db.model('Comment', commentSchema);
 
     return co(function*() {
-      const post = yield Post.create({ name: 'n1'});
+      const post = yield Post.create({ name: 'n1' });
       const comment = yield Comment.create({ postId: post._id, text: 'a comment' });
 
       const doc = yield Post.find({}).populate('comments', 'text').lean();
@@ -7892,7 +7892,7 @@ describe('model: populate:', function() {
     const Dog = db.model('Test', dogSchema);
     const Trick = db.model('Test1', trickSchema);
 
-    const t = new Trick({ description: 'roll over'});
+    const t = new Trick({ description: 'roll over' });
     const d = new Dog({ name: 'Fido', trick: t._id });
     const o = new Owner({ name: 'Bill', age: 10, dogs: [d._id] });
 
@@ -8051,7 +8051,7 @@ describe('model: populate:', function() {
     });
 
     const s2 = new mongoose.Schema({
-      s1: {type: mongoose.Schema.Types.ObjectId, ref: 'schema1'}
+      s1: { type: mongoose.Schema.Types.ObjectId, ref: 'schema1' }
     });
 
     s2.virtual('numS3', {
@@ -8062,7 +8062,7 @@ describe('model: populate:', function() {
     });
 
     const s3 = new mongoose.Schema({
-      s2: {type: mongoose.Schema.Types.ObjectId, ref: 'schema2'}
+      s2: { type: mongoose.Schema.Types.ObjectId, ref: 'schema2' }
     });
 
     return co(function*() {
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index 2c4d5c1c4f1..93b2b0f0c6c 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -36,7 +36,7 @@ describe('model query casting', function() {
     });
 
     BlogPostB = new Schema({
-      title: {$type: String},
+      title: { $type: String },
       author: String,
       slug: String,
       date: Date,
@@ -46,21 +46,21 @@ describe('model query casting', function() {
       },
       published: Boolean,
       mixed: {},
-      numbers: [{$type: Number}],
+      numbers: [{ $type: Number }],
       tags: [String],
       sigs: [Buffer],
       owners: [ObjectId],
       comments: [Comments],
-      def: {$type: String, default: 'kandinsky'}
-    }, {typeKey: '$type'});
+      def: { $type: String, default: 'kandinsky' }
+    }, { typeKey: '$type' });
 
     modelName = 'model.query.casting.blogpost';
     mongoose.model(modelName, BlogPostB);
     collection = 'blogposts_' + random();
 
-    geoSchemaArray = new Schema({loc: {type: [Number], index: '2d'}});
-    geoSchemaObject = new Schema({loc: {long: Number, lat: Number}});
-    geoSchemaObject.index({loc: '2d'});
+    geoSchemaArray = new Schema({ loc: { type: [Number], index: '2d' } });
+    geoSchemaObject = new Schema({ loc: { long: Number, lat: Number } });
+    geoSchemaObject.index({ loc: '2d' });
 
     db = start();
   });
@@ -81,7 +81,7 @@ describe('model query casting', function() {
     post.save(function(err) {
       assert.ifError(err);
 
-      BlogPostB.findOne({_id: id}, function(err, doc) {
+      BlogPostB.findOne({ _id: id }, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.get('title'), title);
         done();
@@ -92,7 +92,7 @@ describe('model query casting', function() {
   it('returns cast errors', function(done) {
     const BlogPostB = db.model(modelName, collection);
 
-    BlogPostB.find({date: 'invalid date'}, function(err) {
+    BlogPostB.find({ date: 'invalid date' }, function(err) {
       assert.ok(err instanceof Error);
       assert.ok(err instanceof CastError);
       done();
@@ -110,7 +110,7 @@ describe('model query casting', function() {
     post.save(function(err) {
       assert.ifError(err);
 
-      BlogPostB.find({'meta.visitors': {$gt: '-100', $lt: -50}},
+      BlogPostB.find({ 'meta.visitors': { $gt: '-100', $lt: -50 } },
         function(err, found) {
           assert.ifError(err);
 
@@ -132,7 +132,7 @@ describe('model query casting', function() {
     post.save(function(err) {
       assert.ifError(err);
 
-      BlogPostB.findOne({_id: {$in: [id]}}, function(err, doc) {
+      BlogPostB.findOne({ _id: { $in: [id] } }, function(err, doc) {
         assert.ifError(err);
 
         assert.equal(doc._id.toString(), id);
@@ -150,7 +150,7 @@ describe('model query casting', function() {
     post.save(function(err) {
       assert.ifError(err);
 
-      BlogPostB.findOne({_id: {$in: id}}, function(err, doc) {
+      BlogPostB.findOne({ _id: { $in: id } }, function(err, doc) {
         assert.ifError(err);
 
         assert.equal(doc._id.toString(), id);
@@ -168,13 +168,13 @@ describe('model query casting', function() {
 
     const Nin = db.model('Nin', 'nins_' + random());
 
-    Nin.create({num: 1}, function(err) {
+    Nin.create({ num: 1 }, function(err) {
       assert.ifError(err);
-      Nin.create({num: 2}, function(err) {
+      Nin.create({ num: 2 }, function(err) {
         assert.ifError(err);
-        Nin.create({num: 3}, function(err) {
+        Nin.create({ num: 3 }, function(err) {
           assert.ifError(err);
-          Nin.find({num: {$nin: [2]}}, function(err, found) {
+          Nin.find({ num: { $nin: [2] } }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 2);
             done();
@@ -194,7 +194,7 @@ describe('model query casting', function() {
     post.save(function(err) {
       assert.ifError(err);
 
-      P.findOne({_id: post._id, 'meta.date': {$lte: Date.now()}}, function(err, doc) {
+      P.findOne({ _id: post._id, 'meta.date': { $lte: Date.now() } }, function(err, doc) {
         assert.ifError(err);
 
         assert.equal(doc._id.toString(), post._id.toString());
@@ -214,10 +214,10 @@ describe('model query casting', function() {
   it('works with $type matching', function(done) {
     const B = db.model(modelName, collection);
 
-    B.find({title: {$type: {x: 1}}}, function(err) {
+    B.find({ title: { $type: { x: 1 } } }, function(err) {
       assert.equal(err.message, '$type parameter must be number or string');
 
-      B.find({title: {$type: 2}}, function(err, posts) {
+      B.find({ title: { $type: 2 } }, function(err, posts) {
         assert.ifError(err);
         assert.strictEqual(Array.isArray(posts), true);
         done();
@@ -228,10 +228,10 @@ describe('model query casting', function() {
   it('works when finding Boolean with $in (gh-998)', function(done) {
     const B = db.model(modelName, collection);
 
-    const b = new B({published: true});
+    const b = new B({ published: true });
     b.save(function(err) {
       assert.ifError(err);
-      B.find({_id: b._id, boolean: {$in: [null, true]}}, function(err, doc) {
+      B.find({ _id: b._id, boolean: { $in: [null, true] } }, function(err, doc) {
         assert.ifError(err);
         assert.ok(doc);
         assert.equal(doc[0].id, b.id);
@@ -243,7 +243,7 @@ describe('model query casting', function() {
   it('works when finding Boolean with $ne (gh-1093)', function(done) {
     const B = db.model(modelName, collection + random());
 
-    const b = new B({published: false});
+    const b = new B({ published: false });
     b.save(function(err) {
       assert.ifError(err);
       B.find().ne('published', true).exec(function(err, doc) {
@@ -257,7 +257,7 @@ describe('model query casting', function() {
 
   it('properly casts $and (gh-1180)', function(done) {
     const B = db.model(modelName, collection + random());
-    const result = B.find({}).cast(B, {$and: [{date: '1987-03-17T20:00:00.000Z'}, {_id: '000000000000000000000000'}]});
+    const result = B.find({}).cast(B, { $and: [{ date: '1987-03-17T20:00:00.000Z' }, { _id: '000000000000000000000000' }] });
     assert.ok(result.$and[0].date instanceof Date);
     assert.ok(result.$and[1]._id instanceof DocumentObjectId);
     done();
@@ -270,7 +270,7 @@ describe('model query casting', function() {
       const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
 
       Test.once('index', complete);
-      Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+      Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
       let pending = 2;
 
@@ -285,7 +285,7 @@ describe('model query casting', function() {
       }
 
       function test() {
-        Test.find({loc: {$near: ['30', '40']}}, function(err, docs) {
+        Test.find({ loc: { $near: ['30', '40'] } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
@@ -309,20 +309,20 @@ describe('model query casting', function() {
       }
 
       function test() {
-        Test.find({loc: {$near: ['30', '40'], $maxDistance: 51}}, function(err, docs) {
+        Test.find({ loc: { $near: ['30', '40'], $maxDistance: 51 } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
         });
       }
 
-      Test.create({loc: {long: 10, lat: 20}}, {loc: {long: 40, lat: 90}}, complete);
+      Test.create({ loc: { long: 10, lat: 20 } }, { loc: { long: 40, lat: 90 } }, complete);
       Test.once('index', complete);
     });
 
     it('with nested objects', function(done) {
-      const geoSchemaObject = new Schema({loc: {nested: {long: Number, lat: Number}}});
-      geoSchemaObject.index({'loc.nested': '2d'});
+      const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
+      geoSchemaObject.index({ 'loc.nested': '2d' });
 
       const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
 
@@ -339,7 +339,7 @@ describe('model query casting', function() {
       }
 
       function test() {
-        Test.find({'loc.nested': {$near: ['30', '40'], $maxDistance: '50'}}, function(err, docs) {
+        Test.find({ 'loc.nested': { $near: ['30', '40'], $maxDistance: '50' } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 1);
           done();
@@ -348,8 +348,8 @@ describe('model query casting', function() {
 
       Test.once('index', complete);
       Test.create(
-        {loc: {nested: {long: 10, lat: 20}}},
-        {loc: {nested: {long: 40, lat: 90}}},
+        { loc: { nested: { long: 10, lat: 20 } } },
+        { loc: { nested: { long: 40, lat: 90 } } },
         complete);
     });
   });
@@ -373,10 +373,10 @@ describe('model query casting', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+      Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
       function test() {
-        Test.find({loc: {$nearSphere: ['30', '40']}}, function(err, docs) {
+        Test.find({ loc: { $nearSphere: ['30', '40'] } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
@@ -400,10 +400,10 @@ describe('model query casting', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: {long: 10, lat: 20}}, {loc: {long: 40, lat: 90}}, complete);
+      Test.create({ loc: { long: 10, lat: 20 } }, { loc: { long: 40, lat: 90 } }, complete);
 
       function test() {
-        Test.find({loc: {$nearSphere: ['30', '40'], $maxDistance: 1}}, function(err, docs) {
+        Test.find({ loc: { $nearSphere: ['30', '40'], $maxDistance: 1 } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
@@ -412,8 +412,8 @@ describe('model query casting', function() {
     });
 
     it('with nested objects', function(done) {
-      const geoSchemaObject = new Schema({loc: {nested: {long: Number, lat: Number}}});
-      geoSchemaObject.index({'loc.nested': '2d'});
+      const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
+      geoSchemaObject.index({ 'loc.nested': '2d' });
 
       const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
 
@@ -430,10 +430,10 @@ describe('model query casting', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: {nested: {long: 10, lat: 20}}}, {loc: {nested: {long: 40, lat: 90}}}, complete);
+      Test.create({ loc: { nested: { long: 10, lat: 20 } } }, { loc: { nested: { long: 40, lat: 90 } } }, complete);
 
       function test() {
-        Test.find({'loc.nested': {$nearSphere: ['30', '40'], $maxDistance: 1}}, function(err, docs) {
+        Test.find({ 'loc.nested': { $nearSphere: ['30', '40'], $maxDistance: 1 } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
@@ -462,10 +462,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+        Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$centerSphere: [['11', '20'], '0.4']}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $centerSphere: [['11', '20'], '0.4'] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             done();
@@ -489,10 +489,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {long: 10, lat: 20}}, {loc: {long: 40, lat: 90}}, complete);
+        Test.create({ loc: { long: 10, lat: 20 } }, { loc: { long: 40, lat: 90 } }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$centerSphere: [['11', '20'], '0.4']}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $centerSphere: [['11', '20'], '0.4'] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             done();
@@ -501,8 +501,8 @@ describe('model query casting', function() {
       });
 
       it('with nested objects', function(done) {
-        const geoSchemaObject = new Schema({loc: {nested: {long: Number, lat: Number}}});
-        geoSchemaObject.index({'loc.nested': '2d'});
+        const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
+        geoSchemaObject.index({ 'loc.nested': '2d' });
 
         const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
 
@@ -519,10 +519,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {nested: {long: 10, lat: 20}}}, {loc: {nested: {long: 40, lat: 90}}}, complete);
+        Test.create({ loc: { nested: { long: 10, lat: 20 } } }, { loc: { nested: { long: 40, lat: 90 } } }, complete);
 
         function test() {
-          Test.find({'loc.nested': {$within: {$centerSphere: [['11', '20'], '0.4']}}}, function(err, docs) {
+          Test.find({ 'loc.nested': { $within: { $centerSphere: [['11', '20'], '0.4'] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             done();
@@ -548,10 +548,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+        Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$center: [['11', '20'], '1']}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $center: [['11', '20'], '1'] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             done();
@@ -575,10 +575,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {long: 10, lat: 20}}, {loc: {long: 40, lat: 90}}, complete);
+        Test.create({ loc: { long: 10, lat: 20 } }, { loc: { long: 40, lat: 90 } }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$center: [['11', '20'], '1']}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $center: [['11', '20'], '1'] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             done();
@@ -587,8 +587,8 @@ describe('model query casting', function() {
       });
 
       it('with nested objects', function(done) {
-        const geoSchemaObject = new Schema({loc: {nested: {long: Number, lat: Number}}});
-        geoSchemaObject.index({'loc.nested': '2d'});
+        const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
+        geoSchemaObject.index({ 'loc.nested': '2d' });
 
         const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
 
@@ -605,10 +605,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {nested: {long: 10, lat: 20}}}, {loc: {nested: {long: 40, lat: 90}}}, complete);
+        Test.create({ loc: { nested: { long: 10, lat: 20 } } }, { loc: { nested: { long: 40, lat: 90 } } }, complete);
 
         function test() {
-          Test.find({'loc.nested': {$within: {$center: [['11', '20'], '1']}}}, function(err, docs) {
+          Test.find({ 'loc.nested': { $within: { $center: [['11', '20'], '1'] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             done();
@@ -634,10 +634,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+        Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$polygon: [['8', '1'], ['8', '100'], ['50', '100'], ['50', '1']]}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $polygon: [['8', '1'], ['8', '100'], ['50', '100'], ['50', '1']] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
             done();
@@ -661,10 +661,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {long: 10, lat: 20}}, {loc: {long: 40, lat: 90}}, complete);
+        Test.create({ loc: { long: 10, lat: 20 } }, { loc: { long: 40, lat: 90 } }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$polygon: [['8', '1'], ['8', '100'], ['50', '100'], ['50', '1']]}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $polygon: [['8', '1'], ['8', '100'], ['50', '100'], ['50', '1']] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
             done();
@@ -673,8 +673,8 @@ describe('model query casting', function() {
       });
 
       it('with nested objects', function(done) {
-        const geoSchemaObject = new Schema({loc: {nested: {long: Number, lat: Number}}});
-        geoSchemaObject.index({'loc.nested': '2d'});
+        const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
+        geoSchemaObject.index({ 'loc.nested': '2d' });
 
         const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
 
@@ -691,10 +691,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {nested: {long: 10, lat: 20}}}, {loc: {nested: {long: 40, lat: 90}}}, complete);
+        Test.create({ loc: { nested: { long: 10, lat: 20 } } }, { loc: { nested: { long: 40, lat: 90 } } }, complete);
 
         function test() {
-          Test.find({'loc.nested': {$within: {$polygon: [['8', '1'], ['8', '100'], ['50', '100'], ['50', '1']]}}}, function(err, docs) {
+          Test.find({ 'loc.nested': { $within: { $polygon: [['8', '1'], ['8', '100'], ['50', '100'], ['50', '1']] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
             done();
@@ -720,10 +720,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+        Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$box: [['8', '1'], ['50', '100']]}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $box: [['8', '1'], ['50', '100']] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
             done();
@@ -747,10 +747,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {long: 10, lat: 20}}, {loc: {long: 40, lat: 90}}, complete);
+        Test.create({ loc: { long: 10, lat: 20 } }, { loc: { long: 40, lat: 90 } }, complete);
 
         function test() {
-          Test.find({loc: {$within: {$box: [['8', '1'], ['50', '100']]}}}, function(err, docs) {
+          Test.find({ loc: { $within: { $box: [['8', '1'], ['50', '100']] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
             done();
@@ -759,8 +759,8 @@ describe('model query casting', function() {
       });
 
       it('with nested objects', function(done) {
-        const geoSchemaObject = new Schema({loc: {nested: {long: Number, lat: Number}}});
-        geoSchemaObject.index({'loc.nested': '2d'});
+        const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
+        geoSchemaObject.index({ 'loc.nested': '2d' });
 
         const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
 
@@ -777,10 +777,10 @@ describe('model query casting', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {nested: {long: 10, lat: 20}}}, {loc: {nested: {long: 40, lat: 90}}}, complete);
+        Test.create({ loc: { nested: { long: 10, lat: 20 } } }, { loc: { nested: { long: 40, lat: 90 } } }, complete);
 
         function test() {
-          Test.find({'loc.nested': {$within: {$box: [['8', '1'], ['50', '100']]}}}, function(err, docs) {
+          Test.find({ 'loc.nested': { $within: { $box: [['8', '1'], ['50', '100']] } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
             done();
@@ -798,7 +798,7 @@ describe('model query casting', function() {
       };
 
       const B = db.model(modelName, collection + random());
-      const result = B.find({}).cast(B, {tags: {$regex: /a/, $options: opts}});
+      const result = B.find({}).cast(B, { tags: { $regex: /a/, $options: opts } });
 
       assert.equal(result.tags.$options, 'img');
       done();
@@ -809,7 +809,7 @@ describe('model query casting', function() {
       });
 
       const Model = db.model('gh7800', testSchema);
-      const result = Model.find({}).cast(Model, {name: {$regex: /a/, $options: 'i'}});
+      const result = Model.find({}).cast(Model, { name: { $regex: /a/, $options: 'i' } });
 
       assert.equal(result.name.$options, 'i');
       done();
@@ -822,13 +822,13 @@ describe('model query casting', function() {
 
       const commentId = mongoose.Types.ObjectId(111);
 
-      const post = new BlogPostB({comments: [{_id: commentId}]});
+      const post = new BlogPostB({ comments: [{ _id: commentId }] });
       const id = post._id.toString();
 
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.findOne({_id: id, comments: {$elemMatch: {_id: commentId.toString()}}}, function(err, doc) {
+        BlogPostB.findOne({ _id: id, comments: { $elemMatch: { _id: commentId.toString() } } }, function(err, doc) {
           assert.ifError(err);
 
           assert.equal(doc._id.toString(), id);
@@ -842,13 +842,13 @@ describe('model query casting', function() {
 
       const commentId = mongoose.Types.ObjectId(111);
 
-      const post = new BlogPostB({comments: [{_id: commentId}]});
+      const post = new BlogPostB({ comments: [{ _id: commentId }] });
       const id = post._id.toString();
 
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.findOne({_id: id, comments: {$not: {$elemMatch: {_id: commentId.toString()}}}}, function(err, doc) {
+        BlogPostB.findOne({ _id: id, comments: { $not: { $elemMatch: { _id: commentId.toString() } } } }, function(err, doc) {
           assert.ifError(err);
 
           assert.equal(doc, null);
@@ -859,8 +859,8 @@ describe('model query casting', function() {
 
     it('should cast subdoc _id typed as String to String in $elemMatch gh3719', function(done) {
       const child = new Schema({
-        _id: {type: String}
-      }, {_id: false});
+        _id: { type: String }
+      }, { _id: false });
 
       const parent = new Schema({
         children: [child]
@@ -868,14 +868,14 @@ describe('model query casting', function() {
 
       const Parent = db.model('gh3719-1', parent);
 
-      Parent.create({children: [{ _id: 'foobar' }] }, function(error) {
+      Parent.create({ children: [{ _id: 'foobar' }] }, function(error) {
         assert.ifError(error);
         test();
       });
 
       function test() {
         Parent.find({
-          $and: [{children: {$elemMatch: {_id: 'foobar'}}}]
+          $and: [{ children: { $elemMatch: { _id: 'foobar' } } }]
         }, function(error, docs) {
           assert.ifError(error);
 
@@ -887,8 +887,8 @@ describe('model query casting', function() {
 
     it('should cast subdoc _id typed as String to String in $elemMatch inside $not gh3719', function(done) {
       const child = new Schema({
-        _id: {type: String}
-      }, {_id: false});
+        _id: { type: String }
+      }, { _id: false });
 
       const parent = new Schema({
         children: [child]
@@ -896,14 +896,14 @@ describe('model query casting', function() {
 
       const Parent = db.model('gh3719-2', parent);
 
-      Parent.create({children: [{ _id: 'foobar' }] }, function(error) {
+      Parent.create({ children: [{ _id: 'foobar' }] }, function(error) {
         assert.ifError(error);
         test();
       });
 
       function test() {
         Parent.find({
-          $and: [{children: {$not: {$elemMatch: {_id: 'foobar'}}}}]
+          $and: [{ children: { $not: { $elemMatch: { _id: 'foobar' } } } }]
         }, function(error, docs) {
           assert.ifError(error);
 
@@ -915,7 +915,7 @@ describe('model query casting', function() {
   });
 
   it('works with $all (gh-3394)', function(done) {
-    const MyModel = db.model('gh3394', {tags: [ObjectId]});
+    const MyModel = db.model('gh3394', { tags: [ObjectId] });
 
     const doc = {
       tags: ['00000000000000000000000a', '00000000000000000000000b']
@@ -924,7 +924,7 @@ describe('model query casting', function() {
     MyModel.create(doc, function(error, savedDoc) {
       assert.ifError(error);
       assert.equal(typeof savedDoc.tags[0], 'object');
-      MyModel.findOne({tags: {$all: doc.tags}}, function(error, doc) {
+      MyModel.findOne({ tags: { $all: doc.tags } }, function(error, doc) {
         assert.ifError(error);
         assert.ok(doc);
         done();
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index dbc039d204d..5d51a674610 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -59,7 +59,7 @@ describe('model: querying:', function() {
       sigs: [Buffer],
       owners: [ObjectId],
       comments: [Comments],
-      def: {type: String, default: 'kandinsky'}
+      def: { type: String, default: 'kandinsky' }
     });
 
     BlogPostB = db.model('BlogPost', BlogPostB);
@@ -68,7 +68,7 @@ describe('model: querying:', function() {
       num: Number, str: String
     });
 
-    geoSchema = new Schema({loc: {type: [Number], index: '2d'}});
+    geoSchema = new Schema({ loc: { type: [Number], index: '2d' } });
   });
 
   let mongo26_or_greater = false;
@@ -142,7 +142,7 @@ describe('model: querying:', function() {
 
   it('a query is executed when a callback is passed', function(done) {
     let count = 5;
-    const q = {_id: new DocumentObjectId}; // make sure the query is fast
+    const q = { _id: new DocumentObjectId }; // make sure the query is fast
 
     function fn() {
       if (--count) {
@@ -169,7 +169,7 @@ describe('model: querying:', function() {
 
   it('query is executed where a callback for findOne', function(done) {
     let count = 5;
-    const q = {_id: new DocumentObjectId}; // make sure the query is fast
+    const q = { _id: new DocumentObjectId }; // make sure the query is fast
 
     function fn() {
       if (--count) {
@@ -229,7 +229,7 @@ describe('model: querying:', function() {
         post.save(function(err) {
           assert.ifError(err);
 
-          BlogPostB.count({title: title}, function(err, count) {
+          BlogPostB.count({ title: title }, function(err, count) {
             assert.ifError(err);
 
             assert.equal(typeof count, 'number');
@@ -249,10 +249,10 @@ describe('model: querying:', function() {
     });
 
     it('executes when you pass a callback', function(done) {
-      let Address = new Schema({zip: String});
+      let Address = new Schema({ zip: String });
       Address = db.model('Test', Address);
 
-      Address.create({zip: '10010'}, {zip: '10010'}, {zip: '99701'}, function(err) {
+      Address.create({ zip: '10010' }, { zip: '10010' }, { zip: '99701' }, function(err) {
         assert.strictEqual(null, err);
         const query = Address.distinct('zip', {}, function(err, results) {
           assert.ifError(err);
@@ -266,9 +266,9 @@ describe('model: querying:', function() {
     });
 
     it('permits excluding conditions gh-1541', function(done) {
-      let Address = new Schema({zip: String});
+      let Address = new Schema({ zip: String });
       Address = db.model('Test', Address);
-      Address.create({zip: '10010'}, {zip: '10010'}, {zip: '99701'}, function(err) {
+      Address.create({ zip: '10010' }, { zip: '10010' }, { zip: '99701' }, function(err) {
         assert.ifError(err);
         Address.distinct('zip', function(err, results) {
           assert.ifError(err);
@@ -298,8 +298,8 @@ describe('model: querying:', function() {
         done();
       }
 
-      assert.ok(BlogPostB.update({title: random()}, {}, fn) instanceof Query);
-      assert.ok(BlogPostB.update({title: random()}, {}, {}, fn) instanceof Query);
+      assert.ok(BlogPostB.update({ title: random() }, {}, fn) instanceof Query);
+      assert.ok(BlogPostB.update({ title: random() }, {}, {}, fn) instanceof Query);
     });
 
     it('can handle minimize option (gh-3381)', function() {
@@ -309,7 +309,7 @@ describe('model: querying:', function() {
       });
 
       return Model.create({}).
-        then(() => Model.replaceOne({}, {mixed: {}, name: 'abc'}, {minimize: true})).
+        then(() => Model.replaceOne({}, { mixed: {}, name: 'abc' }, { minimize: true })).
         then(() => Model.collection.findOne()).
         then(doc => {
           assert.ok(doc.mixed == null);
@@ -330,7 +330,7 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.findOne({title: title}, function(err, doc) {
+        BlogPostB.findOne({ title: title }, function(err, doc) {
           assert.ifError(err);
           assert.equal(title, doc.get('title'));
           assert.equal(doc.isNew, false);
@@ -350,7 +350,7 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        const query = {'meta.visitors': {$gt: '-20', $lt: -1}};
+        const query = { 'meta.visitors': { $gt: '-20', $lt: -1 } };
         BlogPostB.findOne(query, function(err, found) {
           assert.ifError(err);
           assert.ok(found);
@@ -370,11 +370,11 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.findOne({tags: {$in: ['football', 'baseball']}}, function(err, doc) {
+        BlogPostB.findOne({ tags: { $in: ['football', 'baseball'] } }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc._id.toString(), post._id);
 
-          BlogPostB.findOne({_id: post._id, tags: /otba/i}, function(err, doc) {
+          BlogPostB.findOne({ _id: post._id, tags: /otba/i }, function(err, doc) {
             assert.ifError(err);
             assert.equal(doc._id.toString(), post._id);
             done();
@@ -385,12 +385,12 @@ describe('model: querying:', function() {
 
     it('querying if an array contains one of multiple members $in a set 2', function(done) {
       const BlogPostA = BlogPostB;
-      const post = new BlogPostA({tags: ['gooberOne']});
+      const post = new BlogPostA({ tags: ['gooberOne'] });
 
       post.save(function(err) {
         assert.ifError(err);
 
-        const query = {tags: {$in: ['gooberOne']}};
+        const query = { tags: { $in: ['gooberOne'] } };
 
         BlogPostA.findOne(query, function(err, returned) {
           cb();
@@ -400,10 +400,10 @@ describe('model: querying:', function() {
         });
       });
 
-      post.collection.insertOne({meta: {visitors: 9898, a: null}}, {}, function(err, b) {
+      post.collection.insertOne({ meta: { visitors: 9898, a: null } }, {}, function(err, b) {
         assert.ifError(err);
 
-        BlogPostA.findOne({_id: b.ops[0]._id}, function(err, found) {
+        BlogPostA.findOne({ _id: b.ops[0]._id }, function(err, found) {
           cb();
           assert.ifError(err);
           assert.equal(found.get('meta.visitors'), 9898);
@@ -421,10 +421,10 @@ describe('model: querying:', function() {
     });
 
     it('querying via $where a string', function(done) {
-      BlogPostB.create({title: 'Steve Jobs', author: 'Steve Jobs'}, function(err, created) {
+      BlogPostB.create({ title: 'Steve Jobs', author: 'Steve Jobs' }, function(err, created) {
         assert.ifError(err);
 
-        BlogPostB.findOne({$where: 'this.title && this.title === this.author'}, function(err, found) {
+        BlogPostB.findOne({ $where: 'this.title && this.title === this.author' }, function(err, found) {
           assert.ifError(err);
 
           assert.equal(found._id.toString(), created._id);
@@ -434,7 +434,7 @@ describe('model: querying:', function() {
     });
 
     it('querying via $where a function', function(done) {
-      BlogPostB.create({author: 'Atari', slug: 'Atari'}, function(err, created) {
+      BlogPostB.create({ author: 'Atari', slug: 'Atari' }, function(err, created) {
         assert.ifError(err);
 
         BlogPostB.findOne({
@@ -460,7 +460,7 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.findOne({'meta.visitors': 5678}, function(err, found) {
+        BlogPostB.findOne({ 'meta.visitors': 5678 }, function(err, found) {
           assert.ifError(err);
           assert.equal(found.get('meta.visitors')
             .valueOf(), post.get('meta.visitors').valueOf());
@@ -471,22 +471,22 @@ describe('model: querying:', function() {
     });
 
     it('based on embedded doc fields (gh-242, gh-463)', function(done) {
-      BlogPostB.create({comments: [{title: 'i should be queryable'}], numbers: [1, 2, 33333], tags: ['yes', 'no']}, function(err, created) {
+      BlogPostB.create({ comments: [{ title: 'i should be queryable' }], numbers: [1, 2, 33333], tags: ['yes', 'no'] }, function(err, created) {
         assert.ifError(err);
-        BlogPostB.findOne({'comments.title': 'i should be queryable'}, function(err, found) {
+        BlogPostB.findOne({ 'comments.title': 'i should be queryable' }, function(err, found) {
           assert.ifError(err);
           assert.equal(found._id.toString(), created._id);
 
-          BlogPostB.findOne({'comments.0.title': 'i should be queryable'}, function(err, found) {
+          BlogPostB.findOne({ 'comments.0.title': 'i should be queryable' }, function(err, found) {
             assert.ifError(err);
             assert.equal(found._id.toString(), created._id);
 
             // GH-463
-            BlogPostB.findOne({'numbers.2': 33333}, function(err, found) {
+            BlogPostB.findOne({ 'numbers.2': 33333 }, function(err, found) {
               assert.ifError(err);
               assert.equal(found._id.toString(), created._id);
 
-              BlogPostB.findOne({'tags.1': 'no'}, function(err, found) {
+              BlogPostB.findOne({ 'tags.1': 'no' }, function(err, found) {
                 assert.ifError(err);
                 assert.equal(found._id.toString(), created._id);
                 done();
@@ -498,10 +498,10 @@ describe('model: querying:', function() {
     });
 
     it('works with nested docs and string ids (gh-389)', function(done) {
-      BlogPostB.create({comments: [{title: 'i should be queryable by _id'}, {title: 'me too me too!'}]}, function(err, created) {
+      BlogPostB.create({ comments: [{ title: 'i should be queryable by _id' }, { title: 'me too me too!' }] }, function(err, created) {
         assert.ifError(err);
         const id = created.comments[1]._id.toString();
-        BlogPostB.findOne({'comments._id': id}, function(err, found) {
+        BlogPostB.findOne({ 'comments._id': id }, function(err, found) {
           assert.ifError(err);
           assert.strictEqual(!!found, true, 'Find by nested doc id hex string fails');
           assert.equal(found._id.toString(), created._id);
@@ -512,8 +512,8 @@ describe('model: querying:', function() {
 
     it('using #all with nested #elemMatch', function(done) {
       const P = BlogPostB;
-      const post = new P({title: 'nested elemMatch'});
-      post.comments.push({title: 'comment A'}, {title: 'comment B'}, {title: 'comment C'});
+      const post = new P({ title: 'nested elemMatch' });
+      post.comments.push({ title: 'comment A' }, { title: 'comment B' }, { title: 'comment C' });
 
       const id1 = post.comments[1]._id;
       const id2 = post.comments[2]._id;
@@ -521,10 +521,10 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        const query0 = {$elemMatch: {_id: id1, title: 'comment B'}};
-        const query1 = {$elemMatch: {_id: id2.toString(), title: 'comment C'}};
+        const query0 = { $elemMatch: { _id: id1, title: 'comment B' } };
+        const query1 = { $elemMatch: { _id: id2.toString(), title: 'comment C' } };
 
-        P.findOne({comments: {$all: [query0, query1]}}, function(err, p) {
+        P.findOne({ comments: { $all: [query0, query1] } }, function(err, p) {
           assert.ifError(err);
           assert.equal(p.id, post.id);
           done();
@@ -534,18 +534,18 @@ describe('model: querying:', function() {
 
     it('using #or with nested #elemMatch', function(done) {
       const P = BlogPostB;
-      const post = new P({title: 'nested elemMatch'});
-      post.comments.push({title: 'comment D'}, {title: 'comment E'}, {title: 'comment F'});
+      const post = new P({ title: 'nested elemMatch' });
+      post.comments.push({ title: 'comment D' }, { title: 'comment E' }, { title: 'comment F' });
 
       const id1 = post.comments[1]._id;
 
       post.save(function(err) {
         assert.ifError(err);
 
-        const query0 = {comments: {$elemMatch: {title: 'comment Z'}}};
-        const query1 = {comments: {$elemMatch: {_id: id1.toString(), title: 'comment E'}}};
+        const query0 = { comments: { $elemMatch: { title: 'comment Z' } } };
+        const query1 = { comments: { $elemMatch: { _id: id1.toString(), title: 'comment E' } } };
 
-        P.findOne({$or: [query0, query1]}, function(err, p) {
+        P.findOne({ $or: [query0, query1] }, function(err, p) {
           assert.ifError(err);
           assert.equal(p.id, post.id);
           done();
@@ -560,11 +560,11 @@ describe('model: querying:', function() {
           Buffer.from([7, 8, 9])]
       }, function(err, created) {
         assert.ifError(err);
-        BlogPostB.findOne({sigs: Buffer.from([1, 2, 3])}, function(err, found) {
+        BlogPostB.findOne({ sigs: Buffer.from([1, 2, 3]) }, function(err, found) {
           assert.ifError(err);
           found.id;
           assert.equal(found._id.toString(), created._id);
-          const query = {sigs: {$in: [Buffer.from([3, 3, 3]), Buffer.from([4, 5, 6])]}};
+          const query = { sigs: { $in: [Buffer.from([3, 3, 3]), Buffer.from([4, 5, 6])] } };
           BlogPostB.findOne(query, function(err) {
             assert.ifError(err);
             done();
@@ -575,14 +575,14 @@ describe('model: querying:', function() {
 
     it('regex with Array (gh-599)', function(done) {
       const B = BlogPostB;
-      B.create({tags: 'wooof baaaark meeeeow'.split(' ')}, function(err) {
+      B.create({ tags: 'wooof baaaark meeeeow'.split(' ') }, function(err) {
         assert.ifError(err);
-        B.findOne({tags: /ooof$/}, function(err, doc) {
+        B.findOne({ tags: /ooof$/ }, function(err, doc) {
           assert.ifError(err);
           assert.strictEqual(true, !!doc);
           assert.ok(!!~doc.tags.indexOf('meeeeow'));
 
-          B.findOne({tags: {$regex: 'eow$'}}, function(err, doc) {
+          B.findOne({ tags: { $regex: 'eow$' } }, function(err, doc) {
             assert.ifError(err);
             assert.strictEqual(true, !!doc);
             assert.strictEqual(true, !!~doc.tags.indexOf('meeeeow'));
@@ -594,10 +594,10 @@ describe('model: querying:', function() {
 
     it('regex with options', function(done) {
       const B = BlogPostB;
-      const post = new B({title: '$option queries'});
+      const post = new B({ title: '$option queries' });
       post.save(function(err) {
         assert.ifError(err);
-        B.findOne({title: {$regex: ' QUERIES$', $options: 'i'}}, function(err, doc) {
+        B.findOne({ title: { $regex: ' QUERIES$', $options: 'i' } }, function(err, doc) {
           assert.strictEqual(null, err, err && err.stack);
           assert.equal(doc.id, post.id);
           done();
@@ -609,9 +609,9 @@ describe('model: querying:', function() {
       const id1 = new DocumentObjectId;
       const id2 = new DocumentObjectId;
 
-      BlogPostB.create({owners: [id1, id2]}, function(err, created) {
+      BlogPostB.create({ owners: [id1, id2] }, function(err, created) {
         assert.ifError(err);
-        BlogPostB.findOne({owners: {$elemMatch: {$in: [id2.toString()]}}}, function(err, found) {
+        BlogPostB.findOne({ owners: { $elemMatch: { $in: [id2.toString()] } } }, function(err, found) {
           assert.ifError(err);
           assert.ok(found);
           assert.equal(created.id, found.id);
@@ -728,7 +728,7 @@ describe('model: querying:', function() {
           done();
         });
 
-        BlogPostB.findById(post.get('_id'), {title: 1}, function(err, doc) {
+        BlogPostB.findById(post.get('_id'), { title: 1 }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.isInit('title'), true);
           assert.equal(doc.isInit('slug'), false);
@@ -766,7 +766,7 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.findOne({tags: 'cat'}, function(err, doc) {
+        BlogPostB.findOne({ tags: 'cat' }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc._id.toString(), post._id);
           done();
@@ -776,21 +776,21 @@ describe('model: querying:', function() {
 
 
     it('where an array where the $slice operator', function(done) {
-      BlogPostB.create({numbers: [500, 600, 700, 800]}, function(err, created) {
+      BlogPostB.create({ numbers: [500, 600, 700, 800] }, function(err, created) {
         assert.ifError(err);
-        BlogPostB.findById(created._id, {numbers: {$slice: 2}}, function(err, found) {
+        BlogPostB.findById(created._id, { numbers: { $slice: 2 } }, function(err, found) {
           assert.ifError(err);
           assert.equal(found._id.toString(), created._id);
           assert.equal(found.numbers.length, 2);
           assert.equal(found.numbers[0], 500);
           assert.equal(found.numbers[1], 600);
-          BlogPostB.findById(created._id, {numbers: {$slice: -2}}, function(err, found) {
+          BlogPostB.findById(created._id, { numbers: { $slice: -2 } }, function(err, found) {
             assert.ifError(err);
             assert.equal(found._id.toString(), created._id);
             assert.equal(found.numbers.length, 2);
             assert.equal(found.numbers[0], 700);
             assert.equal(found.numbers[1], 800);
-            BlogPostB.findById(created._id, {numbers: {$slice: [1, 2]}}, function(err, found) {
+            BlogPostB.findById(created._id, { numbers: { $slice: [1, 2] } }, function(err, found) {
               assert.ifError(err);
               assert.equal(found._id.toString(), created._id);
               assert.equal(found.numbers.length, 2);
@@ -820,7 +820,7 @@ describe('model: querying:', function() {
         post.save(function(err) {
           assert.ifError(err);
 
-          BlogPostB.find({title: title}, function(err, docs) {
+          BlogPostB.find({ title: title }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 2);
 
@@ -837,9 +837,9 @@ describe('model: querying:', function() {
     });
 
     it('returns docs where an array that contains one specific member', function(done) {
-      BlogPostB.create({numbers: [100, 101, 102]}, function(err, created) {
+      BlogPostB.create({ numbers: [100, 101, 102] }, function(err, created) {
         assert.ifError(err);
-        BlogPostB.find({numbers: 100}, function(err, found) {
+        BlogPostB.find({ numbers: 100 }, function(err, found) {
           assert.ifError(err);
           assert.equal(found.length, 1);
           assert.equal(found[0]._id.toString(), created._id);
@@ -861,23 +861,23 @@ describe('model: querying:', function() {
       const id3 = new DocumentObjectId;
       const id4 = new DocumentObjectId;
 
-      NE.create({ids: [id1, id4], b: id3}, function(err) {
+      NE.create({ ids: [id1, id4], b: id3 }, function(err) {
         assert.ifError(err);
-        NE.create({ids: [id2, id4], b: id3}, function(err) {
+        NE.create({ ids: [id2, id4], b: id3 }, function(err) {
           assert.ifError(err);
 
-          const query = NE.find({b: id3.toString(), ids: {$ne: id1}});
+          const query = NE.find({ b: id3.toString(), ids: { $ne: id1 } });
           query.exec(function(err, nes1) {
             assert.ifError(err);
             assert.equal(nes1.length, 1);
 
-            NE.find({b: {$ne: [1]}}, function(err) {
+            NE.find({ b: { $ne: [1] } }, function(err) {
               assert.equal(err.message, 'Cast to ObjectId failed for value "[ 1 ]" at path "b" for model "NE_Test"');
 
-              NE.find({b: {$ne: 4}}, function(err) {
+              NE.find({ b: { $ne: 4 } }, function(err) {
                 assert.equal(err.message, 'Cast to ObjectId failed for value "4" at path "b" for model "NE_Test"');
 
-                NE.find({b: id3, ids: {$ne: id4}}, function(err, nes4) {
+                NE.find({ b: id3, ids: { $ne: id4 } }, function(err, nes4) {
                   assert.ifError(err);
                   assert.equal(nes4.length, 0);
                   done();
@@ -900,7 +900,7 @@ describe('model: querying:', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPostB.find({_id: post.get('_id')}, function(err, docs) {
+        BlogPostB.find({ _id: post.get('_id') }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs[0].isInit('title'), true);
           assert.equal(docs[0].isInit('slug'), true);
@@ -912,7 +912,7 @@ describe('model: querying:', function() {
           done();
         });
 
-        BlogPostB.find({_id: post.get('_id')}, 'title', function(err, docs) {
+        BlogPostB.find({ _id: post.get('_id') }, 'title', function(err, docs) {
           assert.ifError(err);
           assert.equal(docs[0].isInit('title'), true);
           assert.equal(docs[0].isInit('slug'), false);
@@ -924,7 +924,7 @@ describe('model: querying:', function() {
           done();
         });
 
-        BlogPostB.find({_id: post.get('_id')}, {slug: 0, def: 0}, function(err, docs) {
+        BlogPostB.find({ _id: post.get('_id') }, { slug: 0, def: 0 }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs[0].isInit('title'), true);
           assert.equal(docs[0].isInit('slug'), false);
@@ -936,7 +936,7 @@ describe('model: querying:', function() {
           done();
         });
 
-        BlogPostB.find({_id: post.get('_id')}, 'slug', function(err, docs) {
+        BlogPostB.find({ _id: post.get('_id') }, 'slug', function(err, docs) {
           assert.ifError(err);
           assert.equal(docs[0].isInit('title'), false);
           assert.equal(docs[0].isInit('slug'), true);
@@ -981,9 +981,9 @@ describe('model: querying:', function() {
       const id1 = new DocumentObjectId;
       const id2 = new DocumentObjectId;
 
-      BlogPostB.create({owners: [id1, id2]}, function(err) {
+      BlogPostB.create({ owners: [id1, id2] }, function(err) {
         assert.ifError(err);
-        BlogPostB.find({owners: {$elemMatch: {$in: [id2.toString()]}}}, function(err, found) {
+        BlogPostB.find({ owners: { $elemMatch: { $in: [id2.toString()] } } }, function(err, found) {
           assert.ifError(err);
           assert.equal(found.length, 1);
           done();
@@ -993,11 +993,11 @@ describe('model: querying:', function() {
 
     it('where $mod', function(done) {
       const Mod = db.model('Test', ModSchema);
-      Mod.create({num: 1}, function(err, one) {
+      Mod.create({ num: 1 }, function(err, one) {
         assert.ifError(err);
-        Mod.create({num: 2}, function(err) {
+        Mod.create({ num: 2 }, function(err) {
           assert.ifError(err);
-          Mod.find({num: {$mod: [2, 1]}}, function(err, found) {
+          Mod.find({ num: { $mod: [2, 1] } }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 1);
             assert.equal(found[0]._id.toString(), one._id);
@@ -1009,11 +1009,11 @@ describe('model: querying:', function() {
 
     it('where $not', function(done) {
       const Mod = db.model('Test', ModSchema);
-      Mod.create({num: 1}, function(err) {
+      Mod.create({ num: 1 }, function(err) {
         assert.ifError(err);
-        Mod.create({num: 2}, function(err, two) {
+        Mod.create({ num: 2 }, function(err, two) {
           assert.ifError(err);
-          Mod.find({num: {$not: {$mod: [2, 1]}}}, function(err, found) {
+          Mod.find({ num: { $not: { $mod: [2, 1] } } }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 1);
             assert.equal(found[0]._id.toString(), two._id);
@@ -1026,7 +1026,7 @@ describe('model: querying:', function() {
     it('where or()', function(done) {
       const Mod = db.model('Test', ModSchema);
 
-      Mod.create({num: 1}, {num: 2, str: 'two'}, function(err, one, two) {
+      Mod.create({ num: 1 }, { num: 2, str: 'two' }, function(err, one, two) {
         assert.ifError(err);
 
         let pending = 3;
@@ -1035,7 +1035,7 @@ describe('model: querying:', function() {
         test3();
 
         function test1() {
-          Mod.find({$or: [{num: 1}, {num: 2}]}, function(err, found) {
+          Mod.find({ $or: [{ num: 1 }, { num: 2 }] }, function(err, found) {
             cb();
             assert.ifError(err);
             assert.equal(found.length, 2);
@@ -1057,7 +1057,7 @@ describe('model: querying:', function() {
         }
 
         function test2() {
-          Mod.find({$or: [{str: 'two'}, {str: 'three'}]}, function(err, found) {
+          Mod.find({ $or: [{ str: 'two' }, { str: 'three' }] }, function(err, found) {
             cb();
             assert.ifError(err);
             assert.equal(found.length, 1);
@@ -1066,7 +1066,7 @@ describe('model: querying:', function() {
         }
 
         function test3() {
-          Mod.find({$or: [{num: 1}]}).or([{str: 'two'}]).exec(function(err, found) {
+          Mod.find({ $or: [{ num: 1 }] }).or([{ str: 'two' }]).exec(function(err, found) {
             cb();
             assert.ifError(err);
             assert.equal(found.length, 2);
@@ -1099,11 +1099,11 @@ describe('model: querying:', function() {
     it('using $or with array of Document', function(done) {
       const Mod = db.model('Test', ModSchema);
 
-      Mod.create({num: 1}, function(err, one) {
+      Mod.create({ num: 1 }, function(err, one) {
         assert.ifError(err);
-        Mod.find({num: 1}, function(err, found) {
+        Mod.find({ num: 1 }, function(err, found) {
           assert.ifError(err);
-          Mod.find({$or: found}, function(err, found) {
+          Mod.find({ $or: found }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 1);
             assert.equal(found[0]._id.toString(), one._id);
@@ -1115,13 +1115,13 @@ describe('model: querying:', function() {
 
     it('where $ne', function(done) {
       const Mod = db.model('Test', ModSchema);
-      Mod.create({num: 1}, function(err) {
+      Mod.create({ num: 1 }, function(err) {
         assert.ifError(err);
-        Mod.create({num: 2}, function(err, two) {
+        Mod.create({ num: 2 }, function(err, two) {
           assert.ifError(err);
-          Mod.create({num: 3}, function(err, three) {
+          Mod.create({ num: 3 }, function(err, three) {
             assert.ifError(err);
-            Mod.find({num: {$ne: 1}}, function(err, found) {
+            Mod.find({ num: { $ne: 1 } }, function(err, found) {
               assert.ifError(err);
 
               assert.equal(found.length, 2);
@@ -1137,7 +1137,7 @@ describe('model: querying:', function() {
     it('where $nor', function(done) {
       const Mod = db.model('Test', ModSchema);
 
-      Mod.create({num: 1}, {num: 2, str: 'two'}, function(err, one, two) {
+      Mod.create({ num: 1 }, { num: 2, str: 'two' }, function(err, one, two) {
         assert.ifError(err);
 
         let pending = 3;
@@ -1146,7 +1146,7 @@ describe('model: querying:', function() {
         test3();
 
         function test1() {
-          Mod.find({$nor: [{num: 1}, {num: 3}]}, function(err, found) {
+          Mod.find({ $nor: [{ num: 1 }, { num: 3 }] }, function(err, found) {
             cb();
             assert.ifError(err);
             assert.equal(found.length, 1);
@@ -1155,7 +1155,7 @@ describe('model: querying:', function() {
         }
 
         function test2() {
-          Mod.find({$nor: [{str: 'two'}, {str: 'three'}]}, function(err, found) {
+          Mod.find({ $nor: [{ str: 'two' }, { str: 'three' }] }, function(err, found) {
             cb();
             assert.ifError(err);
             assert.equal(found.length, 1);
@@ -1164,7 +1164,7 @@ describe('model: querying:', function() {
         }
 
         function test3() {
-          Mod.find({$nor: [{num: 2}]}).nor([{str: 'two'}]).exec(function(err, found) {
+          Mod.find({ $nor: [{ num: 2 }] }).nor([{ str: 'two' }]).exec(function(err, found) {
             cb();
             assert.ifError(err);
             assert.equal(found.length, 1);
@@ -1182,11 +1182,11 @@ describe('model: querying:', function() {
     });
 
     it('STRICT null matches', function(done) {
-      const a = {title: 'A', author: null};
-      const b = {title: 'B'};
+      const a = { title: 'A', author: null };
+      const b = { title: 'B' };
       BlogPostB.create(a, b, function(err, createdA) {
         assert.ifError(err);
-        BlogPostB.find({author: {$in: [null], $exists: true}}, function(err, found) {
+        BlogPostB.find({ author: { $in: [null], $exists: true } }, function(err, found) {
           assert.ifError(err);
           assert.equal(found.length, 1);
           assert.equal(found[0]._id.toString(), createdA._id);
@@ -1197,10 +1197,10 @@ describe('model: querying:', function() {
 
     it('null matches null and undefined', function(done) {
       BlogPostB.create(
-        {title: 'A', author: null},
-        {title: 'B'}, function(err) {
+        { title: 'A', author: null },
+        { title: 'B' }, function(err) {
           assert.ifError(err);
-          BlogPostB.find({author: null}, function(err, found) {
+          BlogPostB.find({ author: null }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 2);
             done();
@@ -1209,7 +1209,7 @@ describe('model: querying:', function() {
     });
 
     it('a document whose arrays contain at least $all string values', function(done) {
-      const post = new BlogPostB({title: 'Aristocats'});
+      const post = new BlogPostB({ title: 'Aristocats' });
 
       post.tags.push('onex');
       post.tags.push('twox');
@@ -1221,23 +1221,23 @@ describe('model: querying:', function() {
         BlogPostB.findById(post._id, function(err, post) {
           assert.ifError(err);
 
-          BlogPostB.find({title: {$all: ['Aristocats']}}, function(err, docs) {
+          BlogPostB.find({ title: { $all: ['Aristocats'] } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
 
-            BlogPostB.find({title: {$all: [/^Aristocats/]}}, function(err, docs) {
+            BlogPostB.find({ title: { $all: [/^Aristocats/] } }, function(err, docs) {
               assert.ifError(err);
               assert.equal(docs.length, 1);
 
-              BlogPostB.find({tags: {$all: ['onex', 'twox', 'threex']}}, function(err, docs) {
+              BlogPostB.find({ tags: { $all: ['onex', 'twox', 'threex'] } }, function(err, docs) {
                 assert.ifError(err);
                 assert.equal(docs.length, 1);
 
-                BlogPostB.find({tags: {$all: [/^onex/i]}}, function(err, docs) {
+                BlogPostB.find({ tags: { $all: [/^onex/i] } }, function(err, docs) {
                   assert.ifError(err);
                   assert.equal(docs.length, 1);
 
-                  BlogPostB.findOne({tags: {$all: /^two/}}, function(err, doc) {
+                  BlogPostB.findOne({ tags: { $all: /^two/ } }, function(err, doc) {
                     assert.ifError(err);
                     assert.equal(post.id, doc.id);
                     done();
@@ -1251,10 +1251,10 @@ describe('model: querying:', function() {
     });
 
     it('using #nor with nested #elemMatch', function(done) {
-      const p0 = {title: 'nested $nor elemMatch1', comments: []};
+      const p0 = { title: 'nested $nor elemMatch1', comments: [] };
 
-      const p1 = {title: 'nested $nor elemMatch0', comments: []};
-      p1.comments.push({title: 'comment X'}, {title: 'comment Y'}, {title: 'comment W'});
+      const p1 = { title: 'nested $nor elemMatch0', comments: [] };
+      p1.comments.push({ title: 'comment X' }, { title: 'comment Y' }, { title: 'comment W' });
 
       const P = BlogPostB;
 
@@ -1263,10 +1263,10 @@ describe('model: querying:', function() {
 
         const id = post1.comments[1]._id;
 
-        const query0 = {comments: {$elemMatch: {title: 'comment Z'}}};
-        const query1 = {comments: {$elemMatch: {_id: id.toString(), title: 'comment Y'}}};
+        const query0 = { comments: { $elemMatch: { title: 'comment Z' } } };
+        const query1 = { comments: { $elemMatch: { _id: id.toString(), title: 'comment Y' } } };
 
-        P.find({$nor: [query0, query1]}, function(err, posts) {
+        P.find({ $nor: [query0, query1] }, function(err, posts) {
           assert.ifError(err);
           assert.equal(posts.length, 1);
           assert.equal(posts[0].id, post0.id);
@@ -1276,20 +1276,20 @@ describe('model: querying:', function() {
     });
 
     it('strings via regexp', function(done) {
-      BlogPostB.create({title: 'Next to Normal'}, function(err, created) {
+      BlogPostB.create({ title: 'Next to Normal' }, function(err, created) {
         assert.ifError(err);
-        BlogPostB.findOne({title: /^Next/}, function(err, found) {
+        BlogPostB.findOne({ title: /^Next/ }, function(err, found) {
           assert.ifError(err);
           assert.equal(found._id.toString(), created._id);
 
           const reg = '^Next to Normal$';
 
-          BlogPostB.find({title: {$regex: reg}}, function(err, found) {
+          BlogPostB.find({ title: { $regex: reg } }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 1);
             assert.equal(found[0]._id.toString(), created._id);
 
-            BlogPostB.findOne({title: {$regex: reg}}, function(err, found) {
+            BlogPostB.findOne({ title: { $regex: reg } }, function(err, found) {
               assert.ifError(err);
               assert.equal(found._id.toString(), created._id);
 
@@ -1310,19 +1310,19 @@ describe('model: querying:', function() {
     });
 
     it('a document whose arrays contain at least $all values', function(done) {
-      const a1 = {numbers: [-1, -2, -3, -4], meta: {visitors: 4}};
-      const a2 = {numbers: [0, -1, -2, -3, -4]};
+      const a1 = { numbers: [-1, -2, -3, -4], meta: { visitors: 4 } };
+      const a2 = { numbers: [0, -1, -2, -3, -4] };
       BlogPostB.create(a1, a2, function(err, whereoutZero, whereZero) {
         assert.ifError(err);
 
-        BlogPostB.find({numbers: {$all: [-1, -2, -3, -4]}}, function(err, found) {
+        BlogPostB.find({ numbers: { $all: [-1, -2, -3, -4] } }, function(err, found) {
           assert.ifError(err);
           assert.equal(found.length, 2);
-          BlogPostB.find({'meta.visitors': {$all: [4]}}, function(err, found) {
+          BlogPostB.find({ 'meta.visitors': { $all: [4] } }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 1);
             assert.equal(found[0]._id.toString(), whereoutZero._id);
-            BlogPostB.find({numbers: {$all: [0, -1]}}, function(err, found) {
+            BlogPostB.find({ numbers: { $all: [0, -1] } }, function(err, found) {
               assert.ifError(err);
               assert.equal(found.length, 1);
               assert.equal(found[0]._id.toString(), whereZero._id);
@@ -1334,16 +1334,16 @@ describe('model: querying:', function() {
     });
 
     it('where $size', function(done) {
-      BlogPostB.create({numbers: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]}, function(err) {
+      BlogPostB.create({ numbers: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] }, function(err) {
         assert.ifError(err);
-        BlogPostB.create({numbers: [11, 12, 13, 14, 15, 16, 17, 18, 19, 20]}, function(err) {
+        BlogPostB.create({ numbers: [11, 12, 13, 14, 15, 16, 17, 18, 19, 20] }, function(err) {
           assert.ifError(err);
-          BlogPostB.create({numbers: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]}, function(err) {
+          BlogPostB.create({ numbers: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11] }, function(err) {
             assert.ifError(err);
-            BlogPostB.find({numbers: {$size: 10}}, function(err, found) {
+            BlogPostB.find({ numbers: { $size: 10 } }, function(err, found) {
               assert.ifError(err);
               assert.equal(found.length, 2);
-              BlogPostB.find({numbers: {$size: 11}}, function(err, found) {
+              BlogPostB.find({ numbers: { $size: 11 } }, function(err, found) {
                 assert.ifError(err);
                 assert.equal(found.length, 1);
                 done();
@@ -1355,12 +1355,12 @@ describe('model: querying:', function() {
     });
 
     it('$gt, $lt, $lte, $gte work on strings', function(done) {
-      const D = db.model('Test', new Schema({dt: String}));
+      const D = db.model('Test', new Schema({ dt: String }));
 
-      D.create({dt: '2011-03-30'}, cb);
-      D.create({dt: '2011-03-31'}, cb);
-      D.create({dt: '2011-04-01'}, cb);
-      D.create({dt: '2011-04-02'}, cb);
+      D.create({ dt: '2011-03-30' }, cb);
+      D.create({ dt: '2011-03-31' }, cb);
+      D.create({ dt: '2011-04-01' }, cb);
+      D.create({ dt: '2011-04-02' }, cb);
 
       let pending = 4;
 
@@ -1373,7 +1373,7 @@ describe('model: querying:', function() {
 
         pending = 2;
 
-        D.find({dt: {$gte: '2011-03-30', $lte: '2011-04-01'}}).sort('dt').exec(function(err, docs) {
+        D.find({ dt: { $gte: '2011-03-30', $lte: '2011-04-01' } }).sort('dt').exec(function(err, docs) {
           if (!--pending) {
             done();
           }
@@ -1387,7 +1387,7 @@ describe('model: querying:', function() {
           }));
         });
 
-        D.find({dt: {$gt: '2011-03-30', $lt: '2011-04-02'}}).sort('dt').exec(function(err, docs) {
+        D.find({ dt: { $gt: '2011-03-30', $lt: '2011-04-02' } }).sort('dt').exec(function(err, docs) {
           if (!--pending) {
             done();
           }
@@ -1413,16 +1413,16 @@ describe('model: querying:', function() {
 
         const blogPost = BlogPostB;
 
-        blogPost.collection.createIndex({title: 'text'}, function(error) {
+        blogPost.collection.createIndex({ title: 'text' }, function(error) {
           assert.ifError(error);
-          const a = new blogPost({title: 'querying in mongoose'});
-          const b = new blogPost({title: 'text search in mongoose'});
+          const a = new blogPost({ title: 'querying in mongoose' });
+          const b = new blogPost({ title: 'text search in mongoose' });
           a.save(function(error) {
             assert.ifError(error);
             b.save(function(error) {
               assert.ifError(error);
               blogPost.
-                find({$text: {$search: 'text search'}}, {score: {$meta: 'textScore'}}).
+                find({ $text: { $search: 'text search' } }, { score: { $meta: 'textScore' } }).
                 limit(2).
                 exec(function(error, documents) {
                   assert.ifError(error);
@@ -1483,13 +1483,13 @@ describe('model: querying:', function() {
 
   describe('limit', function() {
     it('works', function(done) {
-      BlogPostB.create({title: 'first limit'}, function(err, first) {
+      BlogPostB.create({ title: 'first limit' }, function(err, first) {
         assert.ifError(err);
-        BlogPostB.create({title: 'second limit'}, function(err, second) {
+        BlogPostB.create({ title: 'second limit' }, function(err, second) {
           assert.ifError(err);
-          BlogPostB.create({title: 'third limit'}, function(err) {
+          BlogPostB.create({ title: 'third limit' }, function(err) {
             assert.ifError(err);
-            BlogPostB.find({title: /limit$/}).limit(2).find(function(err, found) {
+            BlogPostB.find({ title: /limit$/ }).limit(2).find(function(err, found) {
               assert.ifError(err);
               assert.equal(found.length, 2);
               assert.equal(found[0].id, first.id);
@@ -1504,13 +1504,13 @@ describe('model: querying:', function() {
 
   describe('skip', function() {
     it('works', function(done) {
-      BlogPostB.create({title: '1 skip'}, function(err) {
+      BlogPostB.create({ title: '1 skip' }, function(err) {
         assert.ifError(err);
-        BlogPostB.create({title: '2 skip'}, function(err, second) {
+        BlogPostB.create({ title: '2 skip' }, function(err, second) {
           assert.ifError(err);
-          BlogPostB.create({title: '3 skip'}, function(err, third) {
+          BlogPostB.create({ title: '3 skip' }, function(err, third) {
             assert.ifError(err);
-            BlogPostB.find({title: /skip$/}).sort({title: 1}).skip(1).limit(2).find(function(err, found) {
+            BlogPostB.find({ title: /skip$/ }).sort({ title: 1 }).skip(1).limit(2).find(function(err, found) {
               assert.ifError(err);
               assert.equal(found.length, 2);
               assert.equal(found[0].id, second._id);
@@ -1525,11 +1525,11 @@ describe('model: querying:', function() {
 
   describe('sort', function() {
     it('works', function(done) {
-      BlogPostB.create({meta: {visitors: 100}}, function(err, least) {
+      BlogPostB.create({ meta: { visitors: 100 } }, function(err, least) {
         assert.ifError(err);
-        BlogPostB.create({meta: {visitors: 300}}, function(err, largest) {
+        BlogPostB.create({ meta: { visitors: 300 } }, function(err, largest) {
           assert.ifError(err);
-          BlogPostB.create({meta: {visitors: 200}}, function(err, middle) {
+          BlogPostB.create({ meta: { visitors: 200 } }, function(err, middle) {
             assert.ifError(err);
             BlogPostB
               .where('meta.visitors').gt(99).lt(301)
@@ -1553,17 +1553,17 @@ describe('model: querying:', function() {
 
       const blogPost = BlogPostB;
 
-      blogPost.collection.createIndex({title: 'text'}, function(error) {
+      blogPost.collection.createIndex({ title: 'text' }, function(error) {
         assert.ifError(error);
-        const a = new blogPost({title: 'searching in mongoose'});
-        const b = new blogPost({title: 'text search in mongoose'});
+        const a = new blogPost({ title: 'searching in mongoose' });
+        const b = new blogPost({ title: 'text search in mongoose' });
         a.save(function(error) {
           assert.ifError(error);
           b.save(function(error) {
             assert.ifError(error);
             blogPost.
-              find({$text: {$search: 'text search'}}, {score: {$meta: 'textScore'}}).
-              sort({score: {$meta: 'textScore'}}).
+              find({ $text: { $search: 'text search' } }, { score: { $meta: 'textScore' } }).
+              sort({ score: { $meta: 'textScore' } }).
               limit(2).
               exec(function(error, documents) {
                 assert.ifError(error);
@@ -1580,7 +1580,7 @@ describe('model: querying:', function() {
 
   describe('nested mixed "x.y.z"', function() {
     it('works', function(done) {
-      BlogPostB.find({'mixed.nested.stuff': 'skynet'}, function(err) {
+      BlogPostB.find({ 'mixed.nested.stuff': 'skynet' }, function(err) {
         assert.ifError(err);
         done();
       });
@@ -1589,12 +1589,12 @@ describe('model: querying:', function() {
 
   it('by Date (gh-336)', function(done) {
     // GH-336
-    const Test = db.model('TestDateQuery', new Schema({date: Date}), 'datetest_' + random());
+    const Test = db.model('TestDateQuery', new Schema({ date: Date }), 'datetest_' + random());
     const now = new Date;
 
-    Test.create({date: now}, {date: new Date(now - 10000)}, function(err) {
+    Test.create({ date: now }, { date: new Date(now - 10000) }, function(err) {
       assert.ifError(err);
-      Test.find({date: now}, function(err, docs) {
+      Test.find({ date: now }, function(err, docs) {
         assert.ifError(err);
         assert.equal(docs.length, 1);
         done();
@@ -1603,24 +1603,24 @@ describe('model: querying:', function() {
   });
 
   it('mixed types with $elemMatch (gh-591)', function(done) {
-    const S = new Schema({a: [{}], b: Number});
+    const S = new Schema({ a: [{}], b: Number });
     const M = db.model('QueryingMixedArrays', S, random());
 
     const m = new M;
-    m.a = [1, 2, {name: 'Frodo'}, 'IDK', {name: 100}];
+    m.a = [1, 2, { name: 'Frodo' }, 'IDK', { name: 100 }];
     m.b = 10;
 
     m.save(function(err) {
       assert.ifError(err);
 
-      M.find({a: {name: 'Frodo'}, b: '10'}, function(err, docs) {
+      M.find({ a: { name: 'Frodo' }, b: '10' }, function(err, docs) {
         assert.ifError(err);
         assert.equal(docs[0].a.length, 5);
         assert.equal(docs[0].b.valueOf(), 10);
 
         const query = {
           a: {
-            $elemMatch: {name: 100}
+            $elemMatch: { name: 100 }
           }
         };
 
@@ -1635,28 +1635,28 @@ describe('model: querying:', function() {
 
   describe('$all', function() {
     it('with ObjectIds (gh-690)', function(done) {
-      const SSchema = new Schema({name: String});
-      const PSchema = new Schema({sub: [SSchema]});
+      const SSchema = new Schema({ name: String });
+      const PSchema = new Schema({ sub: [SSchema] });
 
       const P = db.model('usingAllWithObjectIds', PSchema);
-      const sub = [{name: 'one'}, {name: 'two'}, {name: 'three'}];
+      const sub = [{ name: 'one' }, { name: 'two' }, { name: 'three' }];
 
-      P.create({sub: sub}, function(err, p) {
+      P.create({ sub: sub }, function(err, p) {
         assert.ifError(err);
 
         const o0 = p.sub[0]._id;
         const o1 = p.sub[1]._id;
         const o2 = p.sub[2]._id;
 
-        P.findOne({'sub._id': {$all: [o1, o2.toString()]}}, function(err, doc) {
+        P.findOne({ 'sub._id': { $all: [o1, o2.toString()] } }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.id, p.id);
 
-          P.findOne({'sub._id': {$all: [o0, new DocumentObjectId]}}, function(err, doc) {
+          P.findOne({ 'sub._id': { $all: [o0, new DocumentObjectId] } }, function(err, doc) {
             assert.ifError(err);
             assert.equal(!!doc, false);
 
-            P.findOne({'sub._id': {$all: [o2]}}, function(err, doc) {
+            P.findOne({ 'sub._id': { $all: [o2] } }, function(err, doc) {
               assert.ifError(err);
               assert.equal(doc.id, p.id);
               done();
@@ -1668,32 +1668,32 @@ describe('model: querying:', function() {
 
     it('with Dates', function(done) {
       this.timeout(process.env.TRAVIS ? 8000 : 4500);
-      const SSchema = new Schema({d: Date});
-      const PSchema = new Schema({sub: [SSchema]});
+      const SSchema = new Schema({ d: Date });
+      const PSchema = new Schema({ sub: [SSchema] });
 
       const P = db.model('usingAllWithDates', PSchema);
       const sub = [
-        {d: new Date},
-        {d: new Date(Date.now() - 10000)},
-        {d: new Date(Date.now() - 30000)}
+        { d: new Date },
+        { d: new Date(Date.now() - 10000) },
+        { d: new Date(Date.now() - 30000) }
       ];
 
-      P.create({sub: sub}, function(err, p) {
+      P.create({ sub: sub }, function(err, p) {
         assert.ifError(err);
 
         const o0 = p.sub[0].d;
         const o1 = p.sub[1].d;
         const o2 = p.sub[2].d;
 
-        P.findOne({'sub.d': {$all: [o1, o2]}}, function(err, doc) {
+        P.findOne({ 'sub.d': { $all: [o1, o2] } }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.id, p.id);
 
-          P.findOne({'sub.d': {$all: [o0, new Date]}}, function(err, doc) {
+          P.findOne({ 'sub.d': { $all: [o0, new Date] } }, function(err, doc) {
             assert.ifError(err);
             assert.equal(!!doc, false);
 
-            P.findOne({'sub.d': {$all: [o2]}}, function(err, doc) {
+            P.findOne({ 'sub.d': { $all: [o2] } }, function(err, doc) {
               assert.ifError(err);
               assert.equal(doc.id, p.id);
               done();
@@ -1717,12 +1717,12 @@ describe('model: querying:', function() {
       });
 
       const next = function() {
-        const schema = new Schema({test: [String]});
+        const schema = new Schema({ test: [String] });
         const MyModel = db.model('gh3163', schema);
 
-        MyModel.create({test: ['log1', 'log2']}, function(error) {
+        MyModel.create({ test: ['log1', 'log2'] }, function(error) {
           assert.ifError(error);
-          const query = {test: {$all: [{$elemMatch: {$regex: /log/g}}]}};
+          const query = { test: { $all: [{ $elemMatch: { $regex: /log/g } }] } };
           MyModel.find(query, function(error, docs) {
             assert.ifError(error);
             assert.equal(docs.length, 1);
@@ -1736,25 +1736,25 @@ describe('model: querying:', function() {
   describe('and', function() {
     it('works with queries gh-1188', function(done) {
       const B = BlogPostB;
-      B.create({title: 'and operator', published: false, author: 'Me'}, function(err) {
+      B.create({ title: 'and operator', published: false, author: 'Me' }, function(err) {
         assert.ifError(err);
 
-        B.find({$and: [{title: 'and operator'}]}, function(err, docs) {
+        B.find({ $and: [{ title: 'and operator' }] }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 1);
 
-          B.find({$and: [{title: 'and operator'}, {published: true}]}, function(err, docs) {
+          B.find({ $and: [{ title: 'and operator' }, { published: true }] }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 0);
 
-            B.find({$and: [{title: 'and operator'}, {published: false}]}, function(err, docs) {
+            B.find({ $and: [{ title: 'and operator' }, { published: false }] }, function(err, docs) {
               assert.ifError(err);
               assert.equal(docs.length, 1);
 
               const query = B.find();
               query.and([
-                {title: 'and operator', published: false},
-                {author: 'Me'}
+                { title: 'and operator', published: false },
+                { author: 'Me' }
               ]);
               query.exec(function(err, docs) {
                 assert.ifError(err);
@@ -1762,8 +1762,8 @@ describe('model: querying:', function() {
 
                 const query = B.find();
                 query.and([
-                  {title: 'and operator', published: false},
-                  {author: 'You'}
+                  { title: 'and operator', published: false },
+                  { author: 'You' }
                 ]);
                 query.exec(function(err, docs) {
                   assert.ifError(err);
@@ -1778,9 +1778,9 @@ describe('model: querying:', function() {
     });
 
     it('works with nested query selectors gh-1884', function(done) {
-      const B = db.model('gh1884', {a: String, b: String}, 'gh1884');
+      const B = db.model('gh1884', { a: String, b: String }, 'gh1884');
 
-      B.deleteOne({$and: [{a: 'coffee'}, {b: {$in: ['bacon', 'eggs']}}]}, function(error) {
+      B.deleteOne({ $and: [{ a: 'coffee' }, { b: { $in: ['bacon', 'eggs'] } }] }, function(error) {
         assert.ifError(error);
         done();
       });
@@ -1788,13 +1788,13 @@ describe('model: querying:', function() {
   });
 
   it('works with different methods and query types', function(done) {
-    const BufSchema = new Schema({name: String, block: Buffer});
+    const BufSchema = new Schema({ name: String, block: Buffer });
     const Test = db.model('BufferTest', BufSchema, 'buffers');
 
-    const docA = {name: 'A', block: Buffer.from('über')};
-    const docB = {name: 'B', block: Buffer.from('buffer shtuffs are neat')};
-    const docC = {name: 'C', block: 'hello world'};
-    const docD = {name: 'D', block: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] }};
+    const docA = { name: 'A', block: Buffer.from('über') };
+    const docB = { name: 'B', block: Buffer.from('buffer shtuffs are neat') };
+    const docC = { name: 'C', block: 'hello world' };
+    const docD = { name: 'D', block: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] } };
 
     Test.create(docA, docB, docC, docD, function(err, a, b, c, d) {
       assert.ifError(err);
@@ -1808,26 +1808,26 @@ describe('model: querying:', function() {
         assert.ifError(err);
         assert.equal(a.block.toString('utf8'), 'über');
 
-        Test.findOne({block: 'buffer shtuffs are neat'}, function(err, rb) {
+        Test.findOne({ block: 'buffer shtuffs are neat' }, function(err, rb) {
           assert.ifError(err);
           assert.equal(rb.block.toString('utf8'), 'buffer shtuffs are neat');
 
-          Test.findOne({block: /buffer/i}, function(err) {
+          Test.findOne({ block: /buffer/i }, function(err) {
             assert.equal(err.message, 'Cast to buffer failed for value ' +
               '"/buffer/i" at path "block" for model "BufferTest"');
-            Test.findOne({block: [195, 188, 98, 101, 114]}, function(err, rb) {
+            Test.findOne({ block: [195, 188, 98, 101, 114] }, function(err, rb) {
               assert.ifError(err);
               assert.equal(rb.block.toString('utf8'), 'über');
 
-              Test.findOne({block: 'aGVsbG8gd29ybGQ='}, function(err, rb) {
+              Test.findOne({ block: 'aGVsbG8gd29ybGQ=' }, function(err, rb) {
                 assert.ifError(err);
                 assert.strictEqual(rb, null);
 
-                Test.findOne({block: Buffer.from('aGVsbG8gd29ybGQ=', 'base64')}, function(err, rb) {
+                Test.findOne({ block: Buffer.from('aGVsbG8gd29ybGQ=', 'base64') }, function(err, rb) {
                   assert.ifError(err);
                   assert.equal(rb.block.toString('utf8'), 'hello world');
 
-                  Test.findOne({block: { type: 'Buffer', data: [195, 188, 98, 101, 114] }}, function(err, rb) {
+                  Test.findOne({ block: { type: 'Buffer', data: [195, 188, 98, 101, 114] } }, function(err, rb) {
                     assert.ifError(err);
                     assert.equal(rb.block.toString('utf8'), 'über');
 
@@ -1847,13 +1847,13 @@ describe('model: querying:', function() {
 
   it('with conditionals', function(done) {
     // $in $nin etc
-    const BufSchema = new Schema({name: String, block: Buffer});
+    const BufSchema = new Schema({ name: String, block: Buffer });
     const Test = db.model('Buffer2', BufSchema, 'buffer_' + random());
 
-    const docA = {name: 'A', block: new MongooseBuffer([195, 188, 98, 101, 114])}; // über
-    const docB = {name: 'B', block: new MongooseBuffer('buffer shtuffs are neat')};
-    const docC = {name: 'C', block: new MongooseBuffer('aGVsbG8gd29ybGQ=', 'base64')};
-    const docD = {name: 'D', block: new MongooseBuffer({ type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] })};
+    const docA = { name: 'A', block: new MongooseBuffer([195, 188, 98, 101, 114]) }; // über
+    const docB = { name: 'B', block: new MongooseBuffer('buffer shtuffs are neat') };
+    const docC = { name: 'C', block: new MongooseBuffer('aGVsbG8gd29ybGQ=', 'base64') };
+    const docD = { name: 'D', block: new MongooseBuffer({ type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] }) };
 
     Test.create(docA, docB, docC, docD, function(err, a, b, c, d) {
       if (err) return done(err);
@@ -1865,46 +1865,46 @@ describe('model: querying:', function() {
         assert.equal(d.block.toString('utf8'), 'gh-6863');
 
         const testPromises = [
-          Test.find({block: {
+          Test.find({ block: {
             $in: [
               [195, 188, 98, 101, 114],
               'buffer shtuffs are neat',
               Buffer.from('aGVsbG8gd29ybGQ=', 'base64'),
               { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] } // gh-6863
-            ]}}).exec().then(tests => {
+            ] } }).exec().then(tests => {
             assert.ifError(err);
             assert.equal(tests.length, 4);
           }),
-          Test.find({block: {$in: ['über', 'hello world']}}).exec().then(tests => {
+          Test.find({ block: { $in: ['über', 'hello world'] } }).exec().then(tests => {
             assert.equal(tests.length, 2);
           }),
-          Test.find({block: {$in: ['über']}}).exec().then(tests => {
+          Test.find({ block: { $in: ['über'] } }).exec().then(tests => {
             assert.equal(tests.length, 1);
             assert.equal(tests[0].block.toString('utf8'), 'über');
           }),
-          Test.find({block: {$nin: ['über']}}).exec().then(tests => {
+          Test.find({ block: { $nin: ['über'] } }).exec().then(tests => {
             assert.equal(tests.length, 3);
           }),
-          Test.find({block: {
+          Test.find({ block: {
             $nin: [
               [195, 188, 98, 101, 114],
               Buffer.from('aGVsbG8gd29ybGQ=', 'base64'),
               { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] } // gh-6863
-            ]}}).exec().then(tests => {
+            ] } }).exec().then(tests => {
             assert.ifError(err);
             assert.equal(tests.length, 1);
             assert.equal(tests[0].block.toString('utf8'), 'buffer shtuffs are neat');
           }),
-          Test.find({block: {$ne: 'über'}}).exec().then(tests => {
+          Test.find({ block: { $ne: 'über' } }).exec().then(tests => {
             assert.equal(tests.length, 3);
           }),
-          Test.find({block: {$gt: 'über'}}).exec().then(tests => {
+          Test.find({ block: { $gt: 'über' } }).exec().then(tests => {
             assert.equal(tests.length, 3);
           }),
-          Test.find({block: {$gte: 'über'}}).exec().then(tests => {
+          Test.find({ block: { $gte: 'über' } }).exec().then(tests => {
             assert.equal(tests.length, 4);
           }),
-          Test.find({block: {$lt: Buffer.from('buffer shtuffs are neat')}}).exec().then(tests => {
+          Test.find({ block: { $lt: Buffer.from('buffer shtuffs are neat') } }).exec().then(tests => {
             assert.ifError(err);
             assert.equal(tests.length, 3);
             const ret = {};
@@ -1914,10 +1914,10 @@ describe('model: querying:', function() {
 
             assert.ok(ret['über'] !== undefined);
           }),
-          Test.find({block: {$lte: 'buffer shtuffs are neat'}}).exec().then(tests => {
+          Test.find({ block: { $lte: 'buffer shtuffs are neat' } }).exec().then(tests => {
             assert.equal(tests.length, 4);
           }),
-          Test.find({block: {$gt: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] }}}).exec().then(tests => {
+          Test.find({ block: { $gt: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] } } }).exec().then(tests => {
             assert.equal(tests.length, 2);
           })
         ];
@@ -1933,10 +1933,10 @@ describe('model: querying:', function() {
   it('with previously existing null values in the db', function(done) {
     const post = new BlogPostB();
 
-    post.collection.insertOne({meta: {visitors: 9898, a: null}}, {}, function(err, b) {
+    post.collection.insertOne({ meta: { visitors: 9898, a: null } }, {}, function(err, b) {
       assert.ifError(err);
 
-      BlogPostB.findOne({_id: b.ops[0]._id}, function(err, found) {
+      BlogPostB.findOne({ _id: b.ops[0]._id }, function(err, found) {
         assert.ifError(err);
         assert.equal(found.get('meta.visitors').valueOf(), 9898);
         done();
@@ -1947,10 +1947,10 @@ describe('model: querying:', function() {
   it('with unused values in the db', function(done) {
     const post = new BlogPostB();
 
-    post.collection.insertOne({meta: {visitors: 9898, color: 'blue'}}, {}, function(err, b) {
+    post.collection.insertOne({ meta: { visitors: 9898, color: 'blue' } }, {}, function(err, b) {
       assert.ifError(err);
 
-      BlogPostB.findOne({_id: b.ops[0]._id}, function(err, found) {
+      BlogPostB.findOne({ _id: b.ops[0]._id }, function(err, found) {
         assert.ifError(err);
         assert.equal(found.get('meta.visitors').valueOf(), 9898);
         found.save(function(err) {
@@ -1978,10 +1978,10 @@ describe('model: querying:', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+      Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
       function test() {
-        Test.find({loc: {$near: [30, 40]}}, function(err, docs) {
+        Test.find({ loc: { $near: [30, 40] } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
@@ -2005,10 +2005,10 @@ describe('model: querying:', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: [35, 50]}, {loc: [-40, -90]}, complete);
+      Test.create({ loc: [35, 50] }, { loc: [-40, -90] }, complete);
 
       function test() {
-        Test.find({loc: {$within: {$box: [[30, 40], [40, 60]]}}}, function(err, docs) {
+        Test.find({ loc: { $within: { $box: [[30, 40], [40, 60]] } } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 1);
           done();
@@ -2032,10 +2032,10 @@ describe('model: querying:', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: [10, 20]}, {loc: [40, 90]}, complete);
+      Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
 
       function test() {
-        Test.find({loc: {$nearSphere: [30, 40]}}, function(err, docs) {
+        Test.find({ loc: { $nearSphere: [30, 40] } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 2);
           done();
@@ -2046,8 +2046,8 @@ describe('model: querying:', function() {
     it('$nearSphere with invalid coordinate does not crash (gh-1874)', function(done) {
       const geoSchema = new Schema({
         loc: {
-          type: {type: String},
-          coordinates: {type: [Number], index: '2dsphere'}
+          type: { type: String },
+          coordinates: { type: [Number], index: '2dsphere' }
         }
       });
       const Test = db.model('gh1874', geoSchema, 'gh1874');
@@ -2066,8 +2066,8 @@ describe('model: querying:', function() {
 
       Test.on('index', complete);
       Test.create(
-        {loc: {coordinates: [30, 41]}},
-        {loc: {coordinates: [31, 40]}},
+        { loc: { coordinates: [30, 41] } },
+        { loc: { coordinates: [31, 40] } },
         complete);
 
       const test = function() {
@@ -2075,7 +2075,7 @@ describe('model: querying:', function() {
         q.find({
           loc: {
             $nearSphere: {
-              $geometry: {type: 'Point', coordinates: [30, 40]},
+              $geometry: { type: 'Point', coordinates: [30, 40] },
               $maxDistance: 10000000
             }
           }
@@ -2106,13 +2106,13 @@ describe('model: querying:', function() {
       }
 
       Test.on('index', complete);
-      Test.create({loc: [20, 80]}, {loc: [25, 30]}, complete);
+      Test.create({ loc: [20, 80] }, { loc: [25, 30] }, complete);
 
       function test() {
-        Test.find({loc: {$near: [25, 31], $maxDistance: 1}}, function(err, docs) {
+        Test.find({ loc: { $near: [25, 31], $maxDistance: 1 } }, function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 1);
-          Test.find({loc: {$near: [25, 32], $maxDistance: 1}}, function(err, docs) {
+          Test.find({ loc: { $near: [25, 32], $maxDistance: 1 } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 0);
             done();
@@ -2128,12 +2128,12 @@ describe('model: querying:', function() {
     let geoMultiSchema;
 
     before(function() {
-      schema2dsphere = new Schema({loc: {type: [Number], index: '2dsphere'}});
+      schema2dsphere = new Schema({ loc: { type: [Number], index: '2dsphere' } });
 
-      geoSchema = new Schema({line: {type: {type: String}, coordinates: []}});
-      geoSchema.index({line: '2dsphere'});
+      geoSchema = new Schema({ line: { type: { type: String }, coordinates: [] } });
+      geoSchema.index({ line: '2dsphere' });
 
-      geoMultiSchema = new Schema({geom: [{type: {type: String}, coordinates: []}]});
+      geoMultiSchema = new Schema({ geom: [{ type: { type: String }, coordinates: [] }] });
       // see mongodb issue SERVER-8907
       // geoMultiSchema.index({ geom: '2dsphere' });
     });
@@ -2177,12 +2177,12 @@ describe('model: querying:', function() {
         Test.on('index', function(err) {
           assert.ifError(err);
 
-          Test.create({loc: [0, 0]}, function(err, created) {
+          Test.create({ loc: [0, 0] }, function(err, created) {
             assert.ifError(err);
 
-            const geojsonPoly = {type: 'Polygon', coordinates: [[[-5, -5], ['-5', 5], [5, 5], [5, -5], [-5, '-5']]]};
+            const geojsonPoly = { type: 'Polygon', coordinates: [[[-5, -5], ['-5', 5], [5, 5], [5, -5], [-5, '-5']]] };
 
-            Test.find({loc: {$within: {$geometry: geojsonPoly}}}, function(err, docs) {
+            Test.find({ loc: { $within: { $geometry: geojsonPoly } } }, function(err, docs) {
               assert.ifError(err);
               assert.equal(docs.length, 1);
               assert.equal(created.id, docs[0].id);
@@ -2210,12 +2210,12 @@ describe('model: querying:', function() {
         Test.on('index', function(err) {
           assert.ifError(err);
 
-          Test.create({line: {type: 'LineString', coordinates: [[-178.0, 10.0], [178.0, 10.0]]}}, function(err, created) {
+          Test.create({ line: { type: 'LineString', coordinates: [[-178.0, 10.0], [178.0, 10.0]] } }, function(err, created) {
             assert.ifError(err);
 
-            const geojsonLine = {type: 'LineString', coordinates: [[180.0, 11.0], [180.0, '9.00']]};
+            const geojsonLine = { type: 'LineString', coordinates: [[180.0, 11.0], [180.0, '9.00']] };
 
-            Test.find({line: {$geoIntersects: {$geometry: geojsonLine}}}, function(err, docs) {
+            Test.find({ line: { $geoIntersects: { $geometry: geojsonLine } } }, function(err, docs) {
               assert.ifError(err);
               assert.equal(docs.length, 1);
               assert.equal(created.id, docs[0].id);
@@ -2238,14 +2238,14 @@ describe('model: querying:', function() {
         const Test = db.model('2dsphere-geo-multi1', geoMultiSchema, 'geospatial' + random());
 
         Test.create({
-          geom: [{type: 'LineString', coordinates: [[-178.0, 10.0], [178.0, 10.0]]},
-            {type: 'LineString', coordinates: [[-178.0, 5.0], [178.0, 5.0]]}]
+          geom: [{ type: 'LineString', coordinates: [[-178.0, 10.0], [178.0, 10.0]] },
+            { type: 'LineString', coordinates: [[-178.0, 5.0], [178.0, 5.0]] }]
         }, function(err, created) {
           assert.ifError(err);
 
-          const geojsonLine = {type: 'LineString', coordinates: [[180.0, 11.0], [180.0, '9.00']]};
+          const geojsonLine = { type: 'LineString', coordinates: [[180.0, 11.0], [180.0, '9.00']] };
 
-          Test.find({geom: {$geoIntersects: {$geometry: geojsonLine}}}, function(err, docs) {
+          Test.find({ geom: { $geoIntersects: { $geometry: geojsonLine } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             assert.equal(created.id, docs[0].id);
@@ -2267,14 +2267,14 @@ describe('model: querying:', function() {
         const Test = db.model('2dsphere-geo-multi2', geoMultiSchema, 'geospatial' + random());
 
         Test.create({
-          geom: [{type: 'Polygon', coordinates: [[[28.7, 41], [29.2, 40.9], [29.1, 41.3], [28.7, 41]]]},
-            {type: 'Polygon', coordinates: [[[-1, -1], [1, -1], [1, 1], [-1, 1], [-1, -1]]]}]
+          geom: [{ type: 'Polygon', coordinates: [[[28.7, 41], [29.2, 40.9], [29.1, 41.3], [28.7, 41]]] },
+            { type: 'Polygon', coordinates: [[[-1, -1], [1, -1], [1, 1], [-1, 1], [-1, -1]]] }]
         }, function(err, created) {
           assert.ifError(err);
 
-          const geojsonPolygon = {type: 'Polygon', coordinates: [[[26, 36], [45, 36], [45, 42], [26, 42], [26, 36]]]};
+          const geojsonPolygon = { type: 'Polygon', coordinates: [[[26, 36], [45, 36], [45, 42], [26, 42], [26, 36]]] };
 
-          Test.find({geom: {$geoIntersects: {$geometry: geojsonPolygon}}}, function(err, docs) {
+          Test.find({ geom: { $geoIntersects: { $geometry: geojsonPolygon } } }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             assert.equal(created.id, docs[0].id);
@@ -2300,17 +2300,17 @@ describe('model: querying:', function() {
         Test.on('index', function(err) {
           assert.ifError(err);
 
-          Test.create({line: {type: 'Point', coordinates: [-179.0, 0.0]}}, function(err, created) {
+          Test.create({ line: { type: 'Point', coordinates: [-179.0, 0.0] } }, function(err, created) {
             assert.ifError(err);
 
-            const geojsonPoint = {type: 'Point', coordinates: [-179.0, 0.0]};
+            const geojsonPoint = { type: 'Point', coordinates: [-179.0, 0.0] };
 
-            Test.find({line: {$near: geojsonPoint}}, function(err, docs) {
+            Test.find({ line: { $near: geojsonPoint } }, function(err, docs) {
               assert.ifError(err);
               assert.equal(docs.length, 1);
               assert.equal(created.id, docs[0].id);
 
-              Test.find({line: {$near: {$geometry: geojsonPoint, $maxDistance: 50}}}, function(err, docs) {
+              Test.find({ line: { $near: { $geometry: geojsonPoint, $maxDistance: 50 } } }, function(err, docs) {
                 assert.ifError(err);
                 assert.equal(docs.length, 1);
                 assert.equal(created.id, docs[0].id);
@@ -2326,8 +2326,8 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const geoJSONSchema = new Schema({loc: {type: {type: String}, coordinates: [Number]}});
-        geoJSONSchema.index({loc: '2dsphere'});
+        const geoJSONSchema = new Schema({ loc: { type: { type: String }, coordinates: [Number] } });
+        geoJSONSchema.index({ loc: '2dsphere' });
         const name = 'geospatial' + random();
         const Test = db.model('Geo1', geoJSONSchema, name);
 
@@ -2344,7 +2344,7 @@ describe('model: querying:', function() {
         }
 
         Test.on('index', complete);
-        Test.create({loc: {type: 'Point', coordinates: [10, 20]}}, {
+        Test.create({ loc: { type: 'Point', coordinates: [10, 20] } }, {
           loc: {
             type: 'Point', coordinates: [40, 90]
           }
@@ -2403,9 +2403,9 @@ describe('model: querying:', function() {
         return done();
       }
       const schemas = [];
-      schemas[0] = new Schema({t: {type: String, index: 'hashed'}});
-      schemas[1] = new Schema({t: {type: String, index: 'hashed', sparse: true}});
-      schemas[2] = new Schema({t: {type: String, index: {type: 'hashed', sparse: true}}});
+      schemas[0] = new Schema({ t: { type: String, index: 'hashed' } });
+      schemas[1] = new Schema({ t: { type: String, index: 'hashed', sparse: true } });
+      schemas[2] = new Schema({ t: { type: String, index: { type: 'hashed', sparse: true } } });
 
       let pending = schemas.length;
 
@@ -2413,7 +2413,7 @@ describe('model: querying:', function() {
         const H = db.model('Hashed' + i, schema);
         H.on('index', function(err) {
           assert.ifError(err);
-          H.collection.getIndexes({full: true}, function(err, indexes) {
+          H.collection.getIndexes({ full: true }, function(err, indexes) {
             assert.ifError(err);
 
             const found = indexes.some(function(index) {
@@ -2421,7 +2421,7 @@ describe('model: querying:', function() {
             });
             assert.ok(found);
 
-            H.create({t: 'hashing'}, {}, function(err, doc1, doc2) {
+            H.create({ t: 'hashing' }, {}, function(err, doc1, doc2) {
               assert.ifError(err);
               assert.ok(doc1);
               assert.ok(doc2);
@@ -2448,11 +2448,11 @@ describe('model: querying:', function() {
 
       post.save(function(err) {
         assert.ifError(err);
-        BlogPostB.find({title: title}).lean().exec(function(err, docs) {
+        BlogPostB.find({ title: title }).lean().exec(function(err, docs) {
           assert.ifError(err);
           assert.equal(docs.length, 1);
           assert.strictEqual(docs[0] instanceof mongoose.Document, false);
-          BlogPostB.find({title: title}, null, {lean: true}, function(err, docs) {
+          BlogPostB.find({ title: title }, null, { lean: true }, function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             assert.strictEqual(docs[0] instanceof mongoose.Document, false);
@@ -2470,7 +2470,7 @@ describe('model: querying:', function() {
 
       post.save(function(err) {
         assert.ifError(err);
-        BlogPostB.findOne({title: title}, null, {lean: true}, function(err, doc) {
+        BlogPostB.findOne({ title: title }, null, { lean: true }, function(err, doc) {
           assert.ifError(err);
           assert.ok(doc);
           assert.strictEqual(false, doc instanceof mongoose.Document);
@@ -2481,15 +2481,15 @@ describe('model: querying:', function() {
     it('properly casts nested and/or queries (gh-676)', function(done) {
       const sch = new Schema({
         num: Number,
-        subdoc: {title: String, num: Number}
+        subdoc: { title: String, num: Number }
       });
 
       const M = mongoose.model('andor' + random(), sch);
 
       const cond = {
         $and: [
-          {$or: [{num: '23'}, {'subdoc.num': '45'}]},
-          {$and: [{'subdoc.title': 233}, {num: '345'}]}
+          { $or: [{ num: '23' }, { 'subdoc.num': '45' }] },
+          { $and: [{ 'subdoc.title': 233 }, { num: '345' }] }
         ]
       };
       const q = M.find(cond);
@@ -2503,13 +2503,13 @@ describe('model: querying:', function() {
     it('properly casts deeply nested and/or queries (gh-676)', function(done) {
       const sch = new Schema({
         num: Number,
-        subdoc: {title: String, num: Number}
+        subdoc: { title: String, num: Number }
       });
 
       const M = mongoose.model('andor' + random(), sch);
 
       const cond = {
-        $and: [{$or: [{$and: [{$or: [{num: '12345'}, {'subdoc.num': '56789'}]}]}]}]
+        $and: [{ $or: [{ $and: [{ $or: [{ num: '12345' }, { 'subdoc.num': '56789' }] }] }] }]
       };
       const q = M.find(cond);
       q._castConditions();
@@ -2520,7 +2520,7 @@ describe('model: querying:', function() {
 
     it('test mongodb crash with invalid objectid string (gh-407)', function(done) {
       const IndexedGuy = new mongoose.Schema({
-        name: {type: String}
+        name: { type: String }
       });
 
       const Guy = db.model('Guy', IndexedGuy);
@@ -2540,14 +2540,14 @@ describe('model: querying:', function() {
     });
 
     it('casts $elemMatch (gh-2199)', function(done) {
-      const schema = new Schema({dates: [Date]});
+      const schema = new Schema({ dates: [Date] });
       const Dates = db.model('Date', schema, 'dates');
 
       const array = ['2014-07-01T02:00:00.000Z', '2014-07-01T04:00:00.000Z'];
-      Dates.create({dates: array}, function(err) {
+      Dates.create({ dates: array }, function(err) {
         assert.ifError(err);
-        const elemMatch = {$gte: '2014-07-01T03:00:00.000Z'};
-        Dates.findOne({}, {dates: {$elemMatch: elemMatch}}, function(err, doc) {
+        const elemMatch = { $gte: '2014-07-01T03:00:00.000Z' };
+        Dates.findOne({}, { dates: { $elemMatch: elemMatch } }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.dates.length, 1);
           assert.equal(doc.dates[0].getTime(),
@@ -2580,7 +2580,7 @@ describe('model: querying:', function() {
 
       it('casts $eq (gh-2752)', function(done) {
         BlogPostB.findOne(
-          {_id: {$eq: '000000000000000000000001'}, numbers: {$eq: [1, 2]}},
+          { _id: { $eq: '000000000000000000000001' }, numbers: { $eq: [1, 2] } },
           function(err, doc) {
             if (mongo26) {
               assert.ifError(err);
diff --git a/test/model.test.js b/test/model.test.js
index d4c70756adf..7ab143ef8eb 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -52,7 +52,7 @@ describe('Model', function() {
       numbers: [Number],
       owners: [ObjectId],
       comments: [Comments],
-      nested: {array: [Number]}
+      nested: { array: [Number] }
     });
 
     BlogPost
@@ -155,13 +155,13 @@ describe('Model', function() {
   it('gh-2140', function(done) {
     db.deleteModel(/Test/);
     const S = new Schema({
-      field: [{text: String}]
+      field: [{ text: String }]
     });
 
     const Model = db.model('Test', S);
     const s = new Model();
     s.field = [null];
-    s.field = [{text: 'text'}];
+    s.field = [{ text: 'text' }];
 
     assert.ok(s.field[0]);
     done();
@@ -174,7 +174,7 @@ describe('Model', function() {
       done();
     });
     it('emits init event', function(done) {
-      const schema = new Schema({name: String});
+      const schema = new Schema({ name: String });
       let model;
 
       schema.on('init', function(model_) {
@@ -219,8 +219,8 @@ describe('Model', function() {
       describe('defaults', function() {
         it('to a non-empty array', function(done) {
           const DefaultArraySchema = new Schema({
-            arr: {type: Array, cast: String, default: ['a', 'b', 'c']},
-            single: {type: Array, cast: String, default: ['a']}
+            arr: { type: Array, cast: String, default: ['a', 'b', 'c'] },
+            single: { type: Array, cast: String, default: ['a'] }
           });
           const DefaultArray = db.model('Test', DefaultArraySchema);
           const arr = new DefaultArray;
@@ -235,7 +235,7 @@ describe('Model', function() {
 
         it('empty', function(done) {
           const DefaultZeroCardArraySchema = new Schema({
-            arr: {type: Array, cast: String, default: []},
+            arr: { type: Array, cast: String, default: [] },
             auto: [Number]
           });
           const DefaultZeroCardArray = db.model('Test', DefaultZeroCardArraySchema);
@@ -320,8 +320,8 @@ describe('Model', function() {
           published: true,
           owners: [new DocumentObjectId, new DocumentObjectId],
           comments: [
-            {title: 'Test', date: new Date, body: 'Test'},
-            {title: 'Super', date: new Date, body: 'Cool'}
+            { title: 'Test', date: new Date, body: 'Test' },
+            { title: 'Super', date: new Date, body: 'Cool' }
           ]
         });
 
@@ -399,7 +399,7 @@ describe('Model', function() {
         post.init({
           title: 'Test',
           slug: 'test',
-          comments: [{title: 'Test', date: new Date, body: 'Test'}]
+          comments: [{ title: 'Test', date: new Date, body: 'Test' }]
         });
 
         assert.equal(post.get('comments')[0].isNew, false);
@@ -407,8 +407,8 @@ describe('Model', function() {
       });
 
       it('isNew on embedded documents after saving', function(done) {
-        const post = new BlogPost({title: 'hocus pocus'});
-        post.comments.push({title: 'Humpty Dumpty', comments: [{title: 'nested'}]});
+        const post = new BlogPost({ title: 'hocus pocus' });
+        post.comments.push({ title: 'Humpty Dumpty', comments: [{ title: 'nested' }] });
         assert.equal(post.get('comments')[0].isNew, true);
         assert.equal(post.get('comments')[0].comments[0].isNew, true);
         post.invalidate('title'); // force error
@@ -429,11 +429,11 @@ describe('Model', function() {
   });
 
   it('collection name can be specified through schema', function(done) {
-    const schema = new Schema({name: String}, {collection: 'tests'});
+    const schema = new Schema({ name: String }, { collection: 'tests' });
     const Named = mongoose.model('CollectionNamedInSchema1', schema);
     assert.equal(Named.prototype.collection.name, 'tests');
 
-    const users2schema = new Schema({name: String}, {collection: 'tests'});
+    const users2schema = new Schema({ name: String }, { collection: 'tests' });
     const Named2 = db.model('FooBar', users2schema);
     assert.equal(Named2.prototype.collection.name, 'tests');
     done();
@@ -539,7 +539,7 @@ describe('Model', function() {
 
   it('no RangeError on remove() of a doc with Number _id (gh-714)', function(done) {
     const MySchema = new Schema({
-      _id: {type: Number},
+      _id: { type: Number },
       name: String
     });
 
@@ -593,7 +593,7 @@ describe('Model', function() {
     });
 
     it('can be defined on embedded documents', function(done) {
-      const ChildSchema = new Schema({name: String});
+      const ChildSchema = new Schema({ name: String });
       ChildSchema.method('talk', function() {
         return 'gaga';
       });
@@ -641,7 +641,7 @@ describe('Model', function() {
 
       let post;
       try {
-        post = new BlogPost({date: 'Test', meta: {date: 'Test'}});
+        post = new BlogPost({ date: 'Test', meta: { date: 'Test' } });
       } catch (e) {
         threw = true;
       }
@@ -705,7 +705,7 @@ describe('Model', function() {
       const post = new BlogPost({
         title: 'Test',
         slug: 'test',
-        comments: [{title: 'Test', date: new Date, body: 'Test'}]
+        comments: [{ title: 'Test', date: new Date, body: 'Test' }]
       });
 
       post.get('comments')[0].set('date', 'invalid');
@@ -729,11 +729,11 @@ describe('Model', function() {
           type: String, validate: failingvalidator
         }
       });
-      const BlogPost = db.model('BlogPost', {subs: [subs]});
+      const BlogPost = db.model('BlogPost', { subs: [subs] });
 
       const post = new BlogPost();
       post.init({
-        subs: [{str: 'gaga'}]
+        subs: [{ str: 'gaga' }]
       });
 
       post.save(function(err) {
@@ -775,10 +775,10 @@ describe('Model', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPost.updateOne({title: 1, _id: id}, {title: 2}, function(err) {
+        BlogPost.updateOne({ title: 1, _id: id }, { title: 2 }, function(err) {
           assert.ifError(err);
 
-          BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+          BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
             assert.ifError(err);
             assert.equal(doc.get('title'), '2');
             done();
@@ -857,8 +857,8 @@ describe('Model', function() {
           curr: String,
           rateName: String
         },
-        created: {type: Date, default: Date.now},
-        valid: {type: Boolean, default: true}
+        created: { type: Date, default: Date.now },
+        valid: { type: Boolean, default: true }
       });
 
       const M = db.model('Test', S);
@@ -894,9 +894,9 @@ describe('Model', function() {
       }
 
       const TestValidation = db.model('Test', new Schema({
-        simple: {type: String, required: true},
-        scope: {type: String, validate: [dovalidate, 'scope failed'], required: true},
-        asyncScope: {type: String, validate: [dovalidateAsync, 'async scope failed'], required: true}
+        simple: { type: String, required: true },
+        scope: { type: String, validate: [dovalidate, 'scope failed'], required: true },
+        asyncScope: { type: String, validate: [dovalidateAsync, 'async scope failed'], required: true }
       }));
 
       const post = new TestValidation();
@@ -922,7 +922,7 @@ describe('Model', function() {
       }
 
       const TestValidationMessage = db.model('Test', new Schema({
-        simple: {type: String, validate: [validate, 'must be abc']}
+        simple: { type: String, validate: [validate, 'must be abc'] }
       }));
 
       const post = new TestValidationMessage();
@@ -951,7 +951,7 @@ describe('Model', function() {
       IntrospectionValidation.schema.path('name').validate(function(value) {
         return value.length < 2;
       }, 'Name cannot be greater than 1 character for path "{PATH}" with value `{VALUE}`');
-      const doc = new IntrospectionValidation({name: 'hi'});
+      const doc = new IntrospectionValidation({ name: 'hi' });
       doc.save(function(err) {
         assert.equal(err.errors.name.message, 'Name cannot be greater than 1 character for path "name" with value `hi`');
         assert.equal(err.name, 'ValidationError');
@@ -962,7 +962,7 @@ describe('Model', function() {
 
     it('of required undefined values', function(done) {
       const TestUndefinedValidation = db.model('Test', new Schema({
-        simple: {type: String, required: true}
+        simple: { type: String, required: true }
       }));
 
       const post = new TestUndefinedValidation;
@@ -981,9 +981,9 @@ describe('Model', function() {
 
     it('save callback should only execute once (gh-319)', function(done) {
       const D = db.model('Test', new Schema({
-        username: {type: String, validate: /^[a-z]{6}$/i},
-        email: {type: String, validate: /^[a-z]{6}$/i},
-        password: {type: String, validate: /^[a-z]{6}$/i}
+        username: { type: String, validate: /^[a-z]{6}$/i },
+        email: { type: String, validate: /^[a-z]{6}$/i },
+        password: { type: String, validate: /^[a-z]{6}$/i }
       }));
 
       const post = new D({
@@ -1021,7 +1021,7 @@ describe('Model', function() {
 
     it('query result', function(done) {
       const TestV = db.model('Test', new Schema({
-        resultv: {type: String, required: true}
+        resultv: { type: String, required: true }
       }));
 
       const post = new TestV;
@@ -1033,7 +1033,7 @@ describe('Model', function() {
         post.resultv = 'yeah';
         post.save(function(err) {
           assert.ifError(err);
-          TestV.findOne({_id: post.id}, function(err, found) {
+          TestV.findOne({ _id: post.id }, function(err, found) {
             assert.ifError(err);
             assert.equal(found.resultv, 'yeah');
             found.save(function(err) {
@@ -1047,13 +1047,13 @@ describe('Model', function() {
 
     it('of required previously existing null values', function(done) {
       const TestP = db.model('Test', new Schema({
-        previous: {type: String, required: true},
+        previous: { type: String, required: true },
         a: String
       }));
 
-      TestP.collection.insertOne({a: null, previous: null}, {}, function(err, f) {
+      TestP.collection.insertOne({ a: null, previous: null }, {}, function(err, f) {
         assert.ifError(err);
-        TestP.findOne({_id: f.ops[0]._id}, function(err, found) {
+        TestP.findOne({ _id: f.ops[0]._id }, function(err, found) {
           assert.ifError(err);
           assert.equal(found.isNew, false);
           assert.strictEqual(found.get('previous'), null);
@@ -1075,7 +1075,7 @@ describe('Model', function() {
     it('nested', function(done) {
       const TestNestedValidation = db.model('Test', new Schema({
         nested: {
-          required: {type: String, required: true}
+          required: { type: String, required: true }
         }
       }));
 
@@ -1095,10 +1095,10 @@ describe('Model', function() {
     });
 
     it('of nested subdocuments', function(done) {
-      const Subsubdocs = new Schema({required: {type: String, required: true}});
+      const Subsubdocs = new Schema({ required: { type: String, required: true } });
 
       const Subdocs = new Schema({
-        required: {type: String, required: true},
+        required: { type: String, required: true },
         subs: [Subsubdocs]
       });
 
@@ -1108,7 +1108,7 @@ describe('Model', function() {
 
       const post = new TestSubdocumentsValidation();
 
-      post.get('items').push({required: '', subs: [{required: ''}]});
+      post.get('items').push({ required: '', subs: [{ required: '' }] });
 
       post.save(function(err) {
         assert.ok(err instanceof MongooseError);
@@ -1147,7 +1147,7 @@ describe('Model', function() {
 
     it('without saving', function(done) {
       const TestCallingValidation = db.model('Test', new Schema({
-        item: {type: String, required: true}
+        item: { type: String, required: true }
       }));
 
       const post = new TestCallingValidation;
@@ -1175,7 +1175,7 @@ describe('Model', function() {
       }
 
       const TestV = db.model('Test', new Schema({
-        result: {type: String, validate: [validator, 'chump validator'], required: false}
+        result: { type: String, validate: [validator, 'chump validator'], required: false }
       }));
 
       const post = new TestV;
@@ -1191,7 +1191,7 @@ describe('Model', function() {
             post = null;
 
         ValidationMiddlewareSchema = new Schema({
-          baz: {type: String}
+          baz: { type: String }
         });
 
         ValidationMiddlewareSchema.pre('validate', function(next) {
@@ -1203,7 +1203,7 @@ describe('Model', function() {
 
         Post = db.model('Test', ValidationMiddlewareSchema);
         post = new Post();
-        post.set({baz: 'bad'});
+        post.set({ baz: 'bad' });
 
         post.save(function(err) {
           assert.ok(err instanceof MongooseError);
@@ -1225,7 +1225,7 @@ describe('Model', function() {
         let post = null;
 
         AsyncValidationMiddlewareSchema = new Schema({
-          prop: {type: String}
+          prop: { type: String }
         });
 
         AsyncValidationMiddlewareSchema.pre('validate', true, function(next, done) {
@@ -1241,7 +1241,7 @@ describe('Model', function() {
 
         Post = db.model('Test', AsyncValidationMiddlewareSchema);
         post = new Post();
-        post.set({prop: 'bad'});
+        post.set({ prop: 'bad' });
 
         post.save(function(err) {
           assert.ok(err instanceof MongooseError);
@@ -1264,10 +1264,10 @@ describe('Model', function() {
         const abc = v => v === 'abc';
 
         ComplexValidationMiddlewareSchema = new Schema({
-          baz: {type: String},
-          abc: {type: String, validate: [abc, 'must be abc']},
-          test: {type: String, validate: [/test/, 'must also be abc']},
-          required: {type: String, required: true}
+          baz: { type: String },
+          abc: { type: String, validate: [abc, 'must be abc'] },
+          test: { type: String, validate: [/test/, 'must also be abc'] },
+          required: { type: String, required: true }
         });
 
         ComplexValidationMiddlewareSchema.pre('validate', true, function(next, done) {
@@ -1329,7 +1329,7 @@ describe('Model', function() {
       const now = Date.now();
 
       const TestDefaults = db.model('Test', new Schema({
-        date: {type: Date, default: now}
+        date: { type: Date, default: now }
       }));
 
       const post = new TestDefaults;
@@ -1343,7 +1343,7 @@ describe('Model', function() {
 
       const TestDefaults = db.model('Test', new Schema({
         nested: {
-          date: {type: Date, default: now}
+          date: { type: Date, default: now }
         }
       }));
 
@@ -1357,7 +1357,7 @@ describe('Model', function() {
       const now = Date.now();
 
       const Items = new Schema({
-        date: {type: Date, default: now}
+        date: { type: Date, default: now }
       });
 
       const TestSubdocumentsDefaults = db.model('Test', new Schema({
@@ -1372,7 +1372,7 @@ describe('Model', function() {
     });
 
     it('allows nulls', function(done) {
-      const T = db.model('Test', new Schema({name: {type: String, default: null}}));
+      const T = db.model('Test', new Schema({ name: { type: String, default: null } }));
       const t = new T();
 
       assert.strictEqual(null, t.name);
@@ -1471,10 +1471,10 @@ describe('Model', function() {
 
   describe('.remove()', function() {
     it('works', function(done) {
-      BlogPost.create({title: 1}, {title: 2}, function(err) {
+      BlogPost.create({ title: 1 }, { title: 2 }, function(err) {
         assert.ifError(err);
 
-        BlogPost.remove({title: 1}, function(err) {
+        BlogPost.remove({ title: 1 }, function(err) {
           assert.ifError(err);
 
           BlogPost.find({}, function(err, found) {
@@ -1488,9 +1488,9 @@ describe('Model', function() {
     });
 
     it('errors when id deselected (gh-3118)', function(done) {
-      BlogPost.create({title: 1}, {title: 2}, function(err) {
+      BlogPost.create({ title: 1 }, { title: 2 }, function(err) {
         assert.ifError(err);
-        BlogPost.findOne({title: 1}, {_id: 0}, function(error, doc) {
+        BlogPost.findOne({ title: 1 }, { _id: 0 }, function(error, doc) {
           assert.ifError(error);
           doc.remove(function(err) {
             assert.ok(err);
@@ -1502,10 +1502,10 @@ describe('Model', function() {
     });
 
     it('should not remove any records when deleting by id undefined', function(done) {
-      BlogPost.create({title: 1}, {title: 2}, function(err) {
+      BlogPost.create({ title: 1 }, { title: 2 }, function(err) {
         assert.ifError(err);
 
-        BlogPost.remove({_id: undefined}, function(err) {
+        BlogPost.remove({ _id: undefined }, function(err) {
           assert.ifError(err);
           BlogPost.find({}, function(err, found) {
             assert.equal(found.length, 2, 'Should not remove any records');
@@ -1516,9 +1516,9 @@ describe('Model', function() {
     });
 
     it('should not remove all documents in the collection (gh-3326)', function(done) {
-      BlogPost.create({title: 1}, {title: 2}, function(err) {
+      BlogPost.create({ title: 1 }, { title: 2 }, function(err) {
         assert.ifError(err);
-        BlogPost.findOne({title: 1}, function(error, doc) {
+        BlogPost.findOne({ title: 1 }, function(error, doc) {
           assert.ifError(error);
           doc.remove(function(err) {
             assert.ifError(err);
@@ -1578,7 +1578,7 @@ describe('Model', function() {
 
       const RH = db.model('Test', RHS);
 
-      RH.create({name: 'to be removed'}, function(err, post) {
+      RH.create({ name: 'to be removed' }, function(err, post) {
         assert.ifError(err);
         assert.ok(post);
         RH.findById(post, function(err, found) {
@@ -1660,8 +1660,8 @@ describe('Model', function() {
     it('with same name on embedded docs do not class', function(done) {
       const Post = new Schema({
         title: String,
-        author: {name: String},
-        subject: {name: String}
+        author: { name: String },
+        subject: { name: String }
       });
 
       db.deleteModel(/BlogPost/);
@@ -1669,8 +1669,8 @@ describe('Model', function() {
 
       const post = new PostModel({
         title: 'Test',
-        author: {name: 'A'},
-        subject: {name: 'B'}
+        author: { name: 'A' },
+        subject: { name: 'B' }
       });
 
       assert.equal(post.author.name, 'A');
@@ -1697,7 +1697,7 @@ describe('Model', function() {
 
       const A = db.model('Test', schema);
 
-      const a = new A({number: 100});
+      const a = new A({ number: 100 });
       assert.equal(called, false);
       let num = a.number;
       assert.equal(called, true);
@@ -1706,7 +1706,7 @@ describe('Model', function() {
 
       called = false;
       const b = new A;
-      b.init({number: 50});
+      b.init({ number: 50 });
       assert.equal(called, false);
       num = b.number;
       assert.equal(called, true);
@@ -1716,7 +1716,7 @@ describe('Model', function() {
     });
 
     it('with type defined with { type: Native } (gh-190)', function(done) {
-      const schema = new Schema({ date: {type: Date} });
+      const schema = new Schema({ date: { type: Date } });
 
       const ShortcutGetter = db.model('Test', schema);
       const post = new ShortcutGetter();
@@ -1825,11 +1825,11 @@ describe('Model', function() {
 
         const T = db.model('Test', schema);
 
-        const t = new T({nest: null});
+        const t = new T({ nest: null });
 
         assert.strictEqual(t.nest.st, undefined);
-        t.nest = {st: 'jsconf rules'};
-        assert.deepEqual(t.nest.toObject(), {st: 'jsconf rules'});
+        t.nest = { st: 'jsconf rules' };
+        assert.deepEqual(t.nest.toObject(), { st: 'jsconf rules' });
         assert.equal(t.nest.st, 'jsconf rules');
 
         t.save(function(err) {
@@ -1847,11 +1847,11 @@ describe('Model', function() {
 
         const T = db.model('Test', schema);
 
-        const t = new T({nest: undefined});
+        const t = new T({ nest: undefined });
 
         assert.strictEqual(t.nest.st, undefined);
-        t.nest = {st: 'jsconf rules'};
-        assert.deepEqual(t.nest.toObject(), {st: 'jsconf rules'});
+        t.nest = { st: 'jsconf rules' };
+        assert.deepEqual(t.nest.toObject(), { st: 'jsconf rules' });
         assert.equal(t.nest.st, 'jsconf rules');
 
         t.save(function(err) {
@@ -1870,12 +1870,12 @@ describe('Model', function() {
 
         const T = db.model('Test', schema);
 
-        const t = new T({nest: null});
+        const t = new T({ nest: null });
 
         t.save(function(err) {
           assert.ifError(err);
 
-          t.nest = {st: 'jsconf rules', yep: 'it does'};
+          t.nest = { st: 'jsconf rules', yep: 'it does' };
 
           // check that entire `nest` object is being $set
           const u = t.$__delta()[1];
@@ -1910,7 +1910,7 @@ describe('Model', function() {
             arrays: []
           }
         }));
-        const doodad = new DooDad({nested: {arrays: []}});
+        const doodad = new DooDad({ nested: { arrays: [] } });
         const date = 1234567890;
 
         doodad.nested.arrays.push(['+10', 'yup', date]);
@@ -1940,12 +1940,12 @@ describe('Model', function() {
 
       it('props can be set directly when property was named "type"', function(done) {
         function def() {
-          return [{x: 1}, {x: 2}, {x: 3}];
+          return [{ x: 1 }, { x: 2 }, { x: 3 }];
         }
 
         const DooDad = db.model('Test', new Schema({
           nested: {
-            type: {type: String, default: 'yep'},
+            type: { type: String, default: 'yep' },
             array: {
               type: Array, default: def
             }
@@ -1960,7 +1960,7 @@ describe('Model', function() {
             assert.ifError(err);
 
             assert.equal(doodad.nested.type, 'yep');
-            assert.deepEqual(doodad.nested.array.toObject(), [{x: 1}, {x: 2}, {x: 3}]);
+            assert.deepEqual(doodad.nested.array.toObject(), [{ x: 1 }, { x: 2 }, { x: 3 }]);
 
             doodad.nested.type = 'nope';
             doodad.nested.array = ['some', 'new', 'stuff'];
@@ -1994,8 +1994,8 @@ describe('Model', function() {
       }
 
       let Location = new Schema({
-        lat: {type: Number, default: 0, set: setLat},
-        long: {type: Number, set: uptick}
+        lat: { type: Number, default: 0, set: setLat },
+        long: { type: Number, set: uptick }
       });
 
       let Deal = new Schema({
@@ -2006,11 +2006,11 @@ describe('Model', function() {
       Location = db.model('Location', Location);
       Deal = db.model('Test', Deal);
 
-      const location = new Location({lat: 1.2, long: 10});
+      const location = new Location({ lat: 1.2, long: 10 });
       assert.equal(location.lat.valueOf(), 1);
       assert.equal(location.long.valueOf(), 1);
 
-      const deal = new Deal({title: 'My deal', locations: [{lat: 1.2, long: 33}]});
+      const deal = new Deal({ title: 'My deal', locations: [{ lat: 1.2, long: 33 }] });
       assert.equal(deal.locations[0].lat.valueOf(), 1);
       assert.equal(deal.locations[0].long.valueOf(), 2);
 
@@ -2061,7 +2061,7 @@ describe('Model', function() {
       const post = new BlogPost;
 
       function complete() {
-        BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+        BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
 
           assert.ifError(err);
           assert.equal(doc.get('comments').length, 5);
@@ -2114,27 +2114,27 @@ describe('Model', function() {
       post.save(function(err) {
         assert.ifError(err);
 
-        BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+        BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
           assert.ifError(err);
-          doc.get('comments').push({title: '1'});
+          doc.get('comments').push({ title: '1' });
           save(doc);
         });
 
-        BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+        BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
           assert.ifError(err);
-          doc.get('comments').push({title: '2'});
+          doc.get('comments').push({ title: '2' });
           save(doc);
         });
 
-        BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+        BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
           assert.ifError(err);
-          doc.get('comments').push({title: '3'});
+          doc.get('comments').push({ title: '3' });
           save(doc);
         });
 
-        BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+        BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
           assert.ifError(err);
-          doc.get('comments').push({title: '4'}, {title: '5'});
+          doc.get('comments').push({ title: '4' }, { title: '5' });
           save(doc);
         });
       });
@@ -2142,7 +2142,7 @@ describe('Model', function() {
 
     it('setting (gh-310)', function(done) {
       BlogPost.create({
-        comments: [{title: 'first-title', body: 'first-body'}]
+        comments: [{ title: 'first-title', body: 'first-body' }]
       }, function(err, blog) {
         assert.ifError(err);
         BlogPost.findById(blog.id, function(err, agent1blog) {
@@ -2269,7 +2269,7 @@ describe('Model', function() {
 
     const Temp = db.model('Test', schema);
 
-    Temp.create({nested: {nums: [1, 2, 3, 4, 5]}}, function(err, t) {
+    Temp.create({ nested: { nums: [1, 2, 3, 4, 5] } }, function(err, t) {
       assert.ifError(err);
       t.nested.nums.pull(1);
       t.nested.nums.pull(2);
@@ -2288,7 +2288,7 @@ describe('Model', function() {
 
     const Temp = db.model('Test', schema);
 
-    const p1 = Temp.create({nested: {nums: [1, 2, 3, 4, 5]}});
+    const p1 = Temp.create({ nested: { nums: [1, 2, 3, 4, 5] } });
     p1.then(function(t) {
       t.nested.nums.pull(1);
       t.nested.nums.pull(2);
@@ -2306,7 +2306,7 @@ describe('Model', function() {
 
     const Temp = db.model('Test', schema);
 
-    Temp.create({nested: {nums: [1, 2, 3, 4, 5]}}, function(err, t) {
+    Temp.create({ nested: { nums: [1, 2, 3, 4, 5] } }, function(err, t) {
       assert.ifError(err);
       t.nested.nums.pull(1);
       assert.equal(t.nested.nums.length, 4);
@@ -2323,7 +2323,7 @@ describe('Model', function() {
 
     const Temp = db.model('Test', schema);
 
-    Temp.create({nested: {nums: [1, 2, 3]}}, function(err, t) {
+    Temp.create({ nested: { nums: [1, 2, 3] } }, function(err, t) {
       assert.ifError(err);
 
       Temp.findById(t._id, function(err, found) {
@@ -2373,7 +2373,7 @@ describe('Model', function() {
       const t = new Temp();
 
       function complete() {
-        Temp.findOne({_id: t.get('_id')}, function(err, doc) {
+        Temp.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.get('nums').length, 3);
 
@@ -2410,13 +2410,13 @@ describe('Model', function() {
       t.save(function(err) {
         assert.ifError(err);
 
-        Temp.findOne({_id: t.get('_id')}, function(err, doc) {
+        Temp.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           doc.get('nums').push(1);
           save(doc);
         });
 
-        Temp.findOne({_id: t.get('_id')}, function(err, doc) {
+        Temp.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           doc.get('nums').push(2, 3);
           save(doc);
@@ -2436,7 +2436,7 @@ describe('Model', function() {
       const t = new StrList();
 
       function complete() {
-        StrList.findOne({_id: t.get('_id')}, function(err, doc) {
+        StrList.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
 
           assert.equal(doc.get('strings').length, 3);
@@ -2474,13 +2474,13 @@ describe('Model', function() {
       t.save(function(err) {
         assert.ifError(err);
 
-        StrList.findOne({_id: t.get('_id')}, function(err, doc) {
+        StrList.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           doc.get('strings').push('a');
           save(doc);
         });
 
-        StrList.findOne({_id: t.get('_id')}, function(err, doc) {
+        StrList.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           doc.get('strings').push('b', 'c');
           save(doc);
@@ -2500,7 +2500,7 @@ describe('Model', function() {
       const t = new BufList();
 
       function complete() {
-        BufList.findOne({_id: t.get('_id')}, function(err, doc) {
+        BufList.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
 
           assert.equal(doc.get('buffers').length, 3);
@@ -2539,13 +2539,13 @@ describe('Model', function() {
       t.save(function(err) {
         assert.ifError(err);
 
-        BufList.findOne({_id: t.get('_id')}, function(err, doc) {
+        BufList.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           doc.get('buffers').push(Buffer.from([140]));
           save(doc);
         });
 
-        BufList.findOne({_id: t.get('_id')}, function(err, doc) {
+        BufList.findOne({ _id: t.get('_id') }, function(err, doc) {
           assert.ifError(err);
           doc.get('buffers').push(Buffer.from([141]), Buffer.from([142]));
           save(doc);
@@ -2555,7 +2555,7 @@ describe('Model', function() {
 
     it('works with modified element properties + doc removal (gh-975)', function(done) {
       const B = BlogPost;
-      const b = new B({comments: [{title: 'gh-975'}]});
+      const b = new B({ comments: [{ title: 'gh-975' }] });
 
       b.save(function(err) {
         assert.ifError(err);
@@ -2568,7 +2568,7 @@ describe('Model', function() {
           b.save(function(err) {
             assert.ifError(err);
 
-            B.findByIdAndUpdate({_id: b._id}, {$set: {comments: [{title: 'a'}]}}, {new: true}, function(err, doc) {
+            B.findByIdAndUpdate({ _id: b._id }, { $set: { comments: [{ title: 'a' }] } }, { new: true }, function(err, doc) {
               assert.ifError(err);
               doc.comments[0].title = 'differ';
               doc.comments[0].remove();
@@ -2616,7 +2616,7 @@ describe('Model', function() {
   });
 
   it('updating an embedded document in an embedded array (gh-255)', function(done) {
-    BlogPost.create({comments: [{title: 'woot'}]}, function(err, post) {
+    BlogPost.create({ comments: [{ title: 'woot' }] }, function(err, post) {
       assert.ifError(err);
       BlogPost.findById(post._id, function(err, found) {
         assert.ifError(err);
@@ -2637,19 +2637,19 @@ describe('Model', function() {
   it('updating an embedded array document to an Object value (gh-334)', function(done) {
     const SubSchema = new Schema({
       name: String,
-      subObj: {subName: String}
+      subObj: { subName: String }
     });
-    const GH334Schema = new Schema({name: String, arrData: [SubSchema]});
+    const GH334Schema = new Schema({ name: String, arrData: [SubSchema] });
 
     const AModel = db.model('Test', GH334Schema);
     const instance = new AModel();
 
-    instance.set({name: 'name-value', arrData: [{name: 'arrName1', subObj: {subName: 'subName1'}}]});
+    instance.set({ name: 'name-value', arrData: [{ name: 'arrName1', subObj: { subName: 'subName1' } }] });
     instance.save(function(err) {
       assert.ifError(err);
       AModel.findById(instance.id, function(err, doc) {
         assert.ifError(err);
-        doc.arrData[0].set('subObj', {subName: 'modified subName'});
+        doc.arrData[0].set('subObj', { subName: 'modified subName' });
         doc.save(function(err) {
           assert.ifError(err);
           AModel.findById(instance.id, function(err, doc) {
@@ -2665,7 +2665,7 @@ describe('Model', function() {
   it('saving an embedded document twice should not push that doc onto the parent doc twice (gh-267)', function(done) {
     const post = new BlogPost();
 
-    post.comments.push({title: 'woot'});
+    post.comments.push({ title: 'woot' });
     post.save(function(err) {
       assert.ifError(err);
       assert.equal(post.comments.length, 1);
@@ -2689,8 +2689,8 @@ describe('Model', function() {
     it('by the id shortcut function', function(done) {
       const post = new BlogPost();
 
-      post.comments.push({title: 'woot'});
-      post.comments.push({title: 'aaaa'});
+      post.comments.push({ title: 'woot' });
+      post.comments.push({ title: 'aaaa' });
 
       const subdoc1 = post.comments[0];
       const subdoc2 = post.comments[1];
@@ -2744,8 +2744,8 @@ describe('Model', function() {
   it('removing a subdocument atomically', function(done) {
     const post = new BlogPost();
     post.title = 'hahaha';
-    post.comments.push({title: 'woot'});
-    post.comments.push({title: 'aaaa'});
+    post.comments.push({ title: 'woot' });
+    post.comments.push({ title: 'aaaa' });
 
     post.save(function(err) {
       assert.ifError(err);
@@ -2771,8 +2771,8 @@ describe('Model', function() {
   it('single pull embedded doc', function(done) {
     const post = new BlogPost();
     post.title = 'hahaha';
-    post.comments.push({title: 'woot'});
-    post.comments.push({title: 'aaaa'});
+    post.comments.push({ title: 'woot' });
+    post.comments.push({ title: 'aaaa' });
 
     post.save(function(err) {
       assert.ifError(err);
@@ -2815,7 +2815,7 @@ describe('Model', function() {
 
     // array
     const post2 = new BlogPost();
-    post2.mixed = {name: 'mr bungle', arr: []};
+    post2.mixed = { name: 'mr bungle', arr: [] };
     post2.save(function(err) {
       assert.ifError(err);
 
@@ -2824,7 +2824,7 @@ describe('Model', function() {
 
         assert.equal(Array.isArray(doc.mixed.arr), true);
 
-        doc.mixed = [{foo: 'bar'}];
+        doc.mixed = [{ foo: 'bar' }];
         doc.save(function(err) {
           assert.ifError(err);
 
@@ -2832,7 +2832,7 @@ describe('Model', function() {
             assert.ifError(err);
 
             assert.equal(Array.isArray(doc.mixed), true);
-            doc.mixed.push({hello: 'world'});
+            doc.mixed.push({ hello: 'world' });
             doc.mixed.push(['foo', 'bar']);
             doc.markModified('mixed');
 
@@ -2842,8 +2842,8 @@ describe('Model', function() {
               BlogPost.findById(post2._id, function(err, doc) {
                 assert.ifError(err);
 
-                assert.deepEqual(doc.mixed[0], {foo: 'bar'});
-                assert.deepEqual(doc.mixed[1], {hello: 'world'});
+                assert.deepEqual(doc.mixed[0], { foo: 'bar' });
+                assert.deepEqual(doc.mixed[1], { hello: 'world' });
                 assert.deepEqual(doc.mixed[2], ['foo', 'bar']);
                 if (--count) {
                   return;
@@ -2892,11 +2892,11 @@ describe('Model', function() {
 
   it('"type" is allowed as a key', function(done) {
     mongoose.model('TestTypeDefaults', new Schema({
-      type: {type: String, default: 'YES!'}
+      type: { type: String, default: 'YES!' }
     }));
 
     const TestDefaults = db.model('Test', new Schema({
-      type: {type: String, default: 'YES!'}
+      type: { type: String, default: 'YES!' }
     }));
 
     let post = new TestDefaults();
@@ -2906,7 +2906,7 @@ describe('Model', function() {
     // GH-402
     db.deleteModel('Test');
     const TestDefaults2 = db.model('Test', new Schema({
-      x: {y: {type: {type: String}, owner: String}}
+      x: { y: { type: { type: String }, owner: String } }
     }));
 
     post = new TestDefaults2;
@@ -2944,7 +2944,7 @@ describe('Model', function() {
   describe('hooks', function() {
     describe('pre', function() {
       it('with undefined and null', function(done) {
-        const schema = new Schema({name: String});
+        const schema = new Schema({ name: String });
         let called = 0;
 
         schema.pre('save', function(next) {
@@ -2958,7 +2958,7 @@ describe('Model', function() {
         });
 
         const S = db.model('Test', schema);
-        const s = new S({name: 'zupa'});
+        const s = new S({ name: 'zupa' });
 
         s.save(function(err) {
           assert.ifError(err);
@@ -2969,7 +2969,7 @@ describe('Model', function() {
 
 
       it('with an async waterfall', function(done) {
-        const schema = new Schema({name: String});
+        const schema = new Schema({ name: String });
         let called = 0;
 
         schema.pre('save', true, function(next, done) {
@@ -2986,7 +2986,7 @@ describe('Model', function() {
         });
 
         const S = db.model('Test', schema);
-        const s = new S({name: 'zupa'});
+        const s = new S({ name: 'zupa' });
 
         const p = s.save();
         p.then(function() {
@@ -2997,19 +2997,19 @@ describe('Model', function() {
 
 
       it('called on all sub levels', function(done) {
-        const grandSchema = new Schema({name: String});
+        const grandSchema = new Schema({ name: String });
         grandSchema.pre('save', function(next) {
           this.name = 'grand';
           next();
         });
 
-        const childSchema = new Schema({name: String, grand: [grandSchema]});
+        const childSchema = new Schema({ name: String, grand: [grandSchema] });
         childSchema.pre('save', function(next) {
           this.name = 'child';
           next();
         });
 
-        const schema = new Schema({name: String, child: [childSchema]});
+        const schema = new Schema({ name: String, child: [childSchema] });
 
         schema.pre('save', function(next) {
           this.name = 'parent';
@@ -3017,7 +3017,7 @@ describe('Model', function() {
         });
 
         const S = db.model('Test', schema);
-        const s = new S({name: 'a', child: [{name: 'b', grand: [{name: 'c'}]}]});
+        const s = new S({ name: 'a', child: [{ name: 'b', grand: [{ name: 'c' }] }] });
 
         s.save(function(err, doc) {
           assert.ifError(err);
@@ -3030,25 +3030,25 @@ describe('Model', function() {
 
 
       it('error on any sub level', function(done) {
-        const grandSchema = new Schema({name: String});
+        const grandSchema = new Schema({ name: String });
         grandSchema.pre('save', function(next) {
           next(new Error('Error 101'));
         });
 
-        const childSchema = new Schema({name: String, grand: [grandSchema]});
+        const childSchema = new Schema({ name: String, grand: [grandSchema] });
         childSchema.pre('save', function(next) {
           this.name = 'child';
           next();
         });
 
-        const schema = new Schema({name: String, child: [childSchema]});
+        const schema = new Schema({ name: String, child: [childSchema] });
         schema.pre('save', function(next) {
           this.name = 'parent';
           next();
         });
 
         const S = db.model('Test', schema);
-        const s = new S({name: 'a', child: [{name: 'b', grand: [{name: 'c'}]}]});
+        const s = new S({ name: 'a', child: [{ name: 'b', grand: [{ name: 'c' }] }] });
 
         s.save(function(err) {
           assert.ok(err instanceof Error);
@@ -3150,7 +3150,7 @@ describe('Model', function() {
 
         const parent = new Parent();
 
-        parent.embeds.push({title: 'Testing post hooks for embedded docs'});
+        parent.embeds.push({ title: 'Testing post hooks for embedded docs' });
 
         parent.save(function(err) {
           assert.ifError(err);
@@ -3163,9 +3163,9 @@ describe('Model', function() {
 
   describe('#exec()', function() {
     it.skip('count()', function(done) {
-      BlogPost.create({title: 'interoperable count as promise'}, function(err) {
+      BlogPost.create({ title: 'interoperable count as promise' }, function(err) {
         assert.ifError(err);
-        const query = BlogPost.count({title: 'interoperable count as promise'});
+        const query = BlogPost.count({ title: 'interoperable count as promise' });
         query.exec(function(err, count) {
           assert.ifError(err);
           assert.equal(count, 1);
@@ -3191,14 +3191,14 @@ describe('Model', function() {
     });
 
     it('update()', function(done) {
-      BlogPost.create({title: 'interoperable update as promise'}, function(err) {
+      BlogPost.create({ title: 'interoperable update as promise' }, function(err) {
         assert.ifError(err);
-        const query = BlogPost.update({title: 'interoperable update as promise'}, {title: 'interoperable update as promise delta'});
+        const query = BlogPost.update({ title: 'interoperable update as promise' }, { title: 'interoperable update as promise delta' });
         query.exec(function(err, res) {
           assert.ifError(err);
           assert.equal(res.n, 1);
           assert.equal(res.nModified, 1);
-          BlogPost.count({title: 'interoperable update as promise delta'}, function(err, count) {
+          BlogPost.count({ title: 'interoperable update as promise delta' }, function(err, count) {
             assert.ifError(err);
             assert.equal(count, 1);
             done();
@@ -3208,9 +3208,9 @@ describe('Model', function() {
     });
 
     it('findOne()', function(done) {
-      BlogPost.create({title: 'interoperable findOne as promise'}, function(err, created) {
+      BlogPost.create({ title: 'interoperable findOne as promise' }, function(err, created) {
         assert.ifError(err);
-        const query = BlogPost.findOne({title: 'interoperable findOne as promise'});
+        const query = BlogPost.findOne({ title: 'interoperable findOne as promise' });
         query.exec(function(err, found) {
           assert.ifError(err);
           assert.equal(found.id, created.id);
@@ -3221,11 +3221,11 @@ describe('Model', function() {
 
     it('find()', function(done) {
       BlogPost.create(
-        {title: 'interoperable find as promise'},
-        {title: 'interoperable find as promise'},
+        { title: 'interoperable find as promise' },
+        { title: 'interoperable find as promise' },
         function(err, createdOne, createdTwo) {
           assert.ifError(err);
-          const query = BlogPost.find({title: 'interoperable find as promise'}).sort('_id');
+          const query = BlogPost.find({ title: 'interoperable find as promise' }).sort('_id');
           query.exec(function(err, found) {
             assert.ifError(err);
             assert.equal(found.length, 2);
@@ -3241,13 +3241,13 @@ describe('Model', function() {
 
     it.skip('remove()', function(done) {
       BlogPost.create(
-        {title: 'interoperable remove as promise'},
+        { title: 'interoperable remove as promise' },
         function(err) {
           assert.ifError(err);
-          const query = BlogPost.remove({title: 'interoperable remove as promise'});
+          const query = BlogPost.remove({ title: 'interoperable remove as promise' });
           query.exec(function(err) {
             assert.ifError(err);
-            BlogPost.count({title: 'interoperable remove as promise'}, function(err, count) {
+            BlogPost.count({ title: 'interoperable remove as promise' }, function(err, count) {
               assert.equal(count, 0);
               done();
             });
@@ -3258,9 +3258,9 @@ describe('Model', function() {
     it('op can be changed', function(done) {
       const title = 'interop ad-hoc as promise';
 
-      BlogPost.create({title: title}, function(err, created) {
+      BlogPost.create({ title: title }, function(err, created) {
         assert.ifError(err);
-        const query = BlogPost.count({title: title});
+        const query = BlogPost.count({ title: title });
         query.exec('findOne', function(err, found) {
           assert.ifError(err);
           assert.equal(found.id, created.id);
@@ -3271,9 +3271,9 @@ describe('Model', function() {
 
     describe('promises', function() {
       it.skip('count()', function(done) {
-        BlogPost.create({title: 'interoperable count as promise 2'}, function(err) {
+        BlogPost.create({ title: 'interoperable count as promise 2' }, function(err) {
           assert.ifError(err);
-          const query = BlogPost.count({title: 'interoperable count as promise 2'});
+          const query = BlogPost.count({ title: 'interoperable count as promise 2' });
           const promise = query.exec();
           promise.then(function(count) {
             assert.equal(count, 1);
@@ -3283,12 +3283,12 @@ describe('Model', function() {
       });
 
       it.skip('update()', function(done) {
-        BlogPost.create({title: 'interoperable update as promise 2'}, function(err) {
+        BlogPost.create({ title: 'interoperable update as promise 2' }, function(err) {
           assert.ifError(err);
-          const query = BlogPost.update({title: 'interoperable update as promise 2'}, {title: 'interoperable update as promise delta 2'});
+          const query = BlogPost.update({ title: 'interoperable update as promise 2' }, { title: 'interoperable update as promise delta 2' });
           const promise = query.exec();
           promise.then(function() {
-            BlogPost.count({title: 'interoperable update as promise delta 2'}, function(err, count) {
+            BlogPost.count({ title: 'interoperable update as promise delta 2' }, function(err, count) {
               assert.ifError(err);
               assert.equal(count, 1);
               done();
@@ -3299,11 +3299,11 @@ describe('Model', function() {
 
       it('findOne()', function() {
         let created;
-        return BlogPost.create({title: 'interoperable findOne as promise 2'}).
+        return BlogPost.create({ title: 'interoperable findOne as promise 2' }).
           then(doc => {
             created = doc;
             return BlogPost.
-              findOne({title: 'interoperable findOne as promise 2'}).
+              findOne({ title: 'interoperable findOne as promise 2' }).
               exec();
           }).
           then(found => {
@@ -3313,11 +3313,11 @@ describe('Model', function() {
 
       it('find()', function(done) {
         BlogPost.create(
-          {title: 'interoperable find as promise 2'},
-          {title: 'interoperable find as promise 2'},
+          { title: 'interoperable find as promise 2' },
+          { title: 'interoperable find as promise 2' },
           function(err, createdOne, createdTwo) {
             assert.ifError(err);
-            const query = BlogPost.find({title: 'interoperable find as promise 2'}).sort('_id');
+            const query = BlogPost.find({ title: 'interoperable find as promise 2' }).sort('_id');
             const promise = query.exec();
             promise.then(function(found) {
               assert.ifError(err);
@@ -3330,12 +3330,12 @@ describe('Model', function() {
       });
 
       it.skip('remove()', function() {
-        return BlogPost.create({title: 'interoperable remove as promise 2'}).
+        return BlogPost.create({ title: 'interoperable remove as promise 2' }).
           then(() => {
-            return BlogPost.remove({title: 'interoperable remove as promise 2'});
+            return BlogPost.remove({ title: 'interoperable remove as promise 2' });
           }).
           then(() => {
-            return BlogPost.count({title: 'interoperable remove as promise 2'});
+            return BlogPost.count({ title: 'interoperable remove as promise 2' });
           }).
           then(count => {
             assert.equal(count, 0);
@@ -3343,23 +3343,23 @@ describe('Model', function() {
       });
 
       it('are thenable', function(done) {
-        const peopleSchema = new Schema({name: String, likes: ['ObjectId']});
+        const peopleSchema = new Schema({ name: String, likes: ['ObjectId'] });
         const P = db.model('Test', peopleSchema);
         BlogPost.create(
-          {title: 'then promise 1'},
-          {title: 'then promise 2'},
-          {title: 'then promise 3'},
+          { title: 'then promise 1' },
+          { title: 'then promise 2' },
+          { title: 'then promise 3' },
           function(err, d1, d2, d3) {
             assert.ifError(err);
 
             P.create(
-              {name: 'brandon', likes: [d1]},
-              {name: 'ben', likes: [d2]},
-              {name: 'bernie', likes: [d3]},
+              { name: 'brandon', likes: [d1] },
+              { name: 'ben', likes: [d2] },
+              { name: 'bernie', likes: [d3] },
               function(err) {
                 assert.ifError(err);
 
-                const promise = BlogPost.find({title: /^then promise/}).select('_id').exec();
+                const promise = BlogPost.find({ title: /^then promise/ }).select('_id').exec();
                 promise.then(function(blogs) {
                   const ids = blogs.map(function(m) {
                     return m._id;
@@ -3393,10 +3393,10 @@ describe('Model', function() {
         date: date,
         numbers: [5, 6, 7],
         owners: [id1],
-        meta: {visitors: 45},
+        meta: { visitors: 45 },
         comments: [
-          {_id: id2, title: 'my comment', date: date, body: 'this is a comment'},
-          {_id: id3, title: 'the next thang', date: date, body: 'this is a comment too!'}]
+          { _id: id2, title: 'my comment', date: date, body: 'this is a comment' },
+          { _id: id3, title: 'the next thang', date: date, body: 'this is a comment too!' }]
       });
 
       const out = post.inspect();
@@ -3410,11 +3410,11 @@ describe('Model', function() {
 
   describe('pathnames', function() {
     it('named path can be used', function(done) {
-      const P = db.model('Test', new Schema({path: String}));
+      const P = db.model('Test', new Schema({ path: String }));
 
       let threw = false;
       try {
-        new P({path: 'i should not throw'});
+        new P({ path: 'i should not throw' });
       } catch (err) {
         threw = true;
       }
@@ -3425,10 +3425,10 @@ describe('Model', function() {
   });
 
   it('subdocuments with changed values should persist the values', function(done) {
-    const Subdoc = new Schema({name: String, mixed: Schema.Types.Mixed});
-    const T = db.model('Test', new Schema({subs: [Subdoc]}));
+    const Subdoc = new Schema({ name: String, mixed: Schema.Types.Mixed });
+    const T = db.model('Test', new Schema({ subs: [Subdoc] }));
 
-    const t = new T({subs: [{name: 'Hubot', mixed: {w: 1, x: 2}}]});
+    const t = new T({ subs: [{ name: 'Hubot', mixed: { w: 1, x: 2 } }] });
     assert.equal(t.subs[0].name, 'Hubot');
     assert.equal(t.subs[0].mixed.w, 1);
     assert.equal(t.subs[0].mixed.x, 2);
@@ -3481,7 +3481,7 @@ describe('Model', function() {
 
   describe('RegExps', function() {
     it('can be saved', function(done) {
-      const post = new BlogPost({mixed: {rgx: /^asdf$/}});
+      const post = new BlogPost({ mixed: { rgx: /^asdf$/ } });
       assert.ok(post.mixed.rgx instanceof RegExp);
       assert.equal(post.mixed.rgx.source, '^asdf$');
       post.save(function(err) {
@@ -3499,7 +3499,7 @@ describe('Model', function() {
   // Demonstration showing why GH-261 is a misunderstanding
   it('a single instantiated document should be able to update its embedded documents more than once', function(done) {
     const post = new BlogPost();
-    post.comments.push({title: 'one'});
+    post.comments.push({ title: 'one' });
     post.save(function(err) {
       assert.ifError(err);
       assert.equal(post.comments[0].title, 'one');
@@ -3536,7 +3536,7 @@ describe('Model', function() {
     });
 
     it('saved changes made within callback of a previous no-op save gh-1139', function(done) {
-      const post = new BlogPost({title: 'first'});
+      const post = new BlogPost({ title: 'first' });
       post.save(function(err) {
         assert.ifError(err);
 
@@ -3559,7 +3559,7 @@ describe('Model', function() {
     });
 
     it('rejects new documents that have no _id set (1595)', function(done) {
-      const s = new Schema({_id: {type: String}});
+      const s = new Schema({ _id: { type: String } });
       const B = db.model('Test', s);
       const b = new B;
       b.save(function(err) {
@@ -3571,23 +3571,23 @@ describe('Model', function() {
 
     it('no TypeError when attempting to save more than once after using atomics', function(done) {
       const M = db.model('Test', new Schema({
-        test: {type: 'string', unique: true},
+        test: { type: 'string', unique: true },
         elements: [{
-          el: {type: 'string', required: true}
+          el: { type: 'string', required: true }
         }]
       }));
       const a = new M({
         test: 'a',
-        elements: [{el: 'b'}]
+        elements: [{ el: 'b' }]
       });
       const b = new M({
         test: 'b',
-        elements: [{el: 'c'}]
+        elements: [{ el: 'c' }]
       });
       M.init(function() {
         a.save(function() {
           b.save(function() {
-            b.elements.push({el: 'd'});
+            b.elements.push({ el: 'd' });
             b.test = 'a';
             b.save(function(error, res) {
               assert.ok(error);
@@ -3603,7 +3603,7 @@ describe('Model', function() {
       });
     });
     it('should clear $versionError and saveOptions after saved (gh-8040)', function(done) {
-      const schema = new Schema({name: String});
+      const schema = new Schema({ name: String });
       const Model = db.model('Test', schema);
       const doc = new Model({
         name: 'Fonger'
@@ -3624,7 +3624,7 @@ describe('Model', function() {
 
   describe('_delta()', function() {
     it('should overwrite arrays when directly set (gh-1126)', function(done) {
-      BlogPost.create({title: 'gh-1126', numbers: [1, 2]}, function(err, b) {
+      BlogPost.create({ title: 'gh-1126', numbers: [1, 2] }, function(err, b) {
         assert.ifError(err);
         BlogPost.findById(b._id, function(err, b) {
           assert.ifError(err);
@@ -3674,7 +3674,7 @@ describe('Model', function() {
     it('should use $set when subdoc changed before pulling (gh-1303)', function(done) {
       const B = BlogPost;
       B.create(
-        {title: 'gh-1303', comments: [{body: 'a'}, {body: 'b'}, {body: 'c'}]},
+        { title: 'gh-1303', comments: [{ body: 'a' }, { body: 'b' }, { body: 'c' }] },
         function(err, b) {
           assert.ifError(err);
           B.findById(b._id, function(err, b) {
@@ -3711,9 +3711,9 @@ describe('Model', function() {
 
   describe('backward compatibility', function() {
     it('with conflicted data in db', function(done) {
-      const M = db.model('Test', new Schema({namey: {first: String, last: String}}));
-      const m = new M({namey: '[object Object]'});
-      m.namey = {first: 'GI', last: 'Joe'};// <-- should overwrite the string
+      const M = db.model('Test', new Schema({ namey: { first: String, last: String } }));
+      const m = new M({ namey: '[object Object]' });
+      m.namey = { first: 'GI', last: 'Joe' };// <-- should overwrite the string
       m.save(function(err) {
         assert.strictEqual(err, null);
         assert.strictEqual('GI', m.namey.first);
@@ -3725,18 +3725,18 @@ describe('Model', function() {
     it('with positional notation on path not existing in schema (gh-1048)', function(done) {
       const db = start();
 
-      const M = db.model('Test', Schema({name: 'string'}));
+      const M = db.model('Test', Schema({ name: 'string' }));
       db.on('open', function() {
         const o = {
           name: 'gh-1048',
           _id: new mongoose.Types.ObjectId,
           databases: {
-            0: {keys: 100, expires: 0},
-            15: {keys: 1, expires: 0}
+            0: { keys: 100, expires: 0 },
+            15: { keys: 1, expires: 0 }
           }
         };
 
-        M.collection.insertOne(o, {safe: true}, function(err) {
+        M.collection.insertOne(o, { safe: true }, function(err) {
           assert.ifError(err);
           M.findById(o._id, function(err, doc) {
             db.close();
@@ -3761,7 +3761,7 @@ describe('Model', function() {
       b.whateveriwant = 10;
       b.save(function(err) {
         assert.ifError(err);
-        B.collection.findOne({_id: b._id}, function(err, doc) {
+        B.collection.findOne({ _id: b._id }, function(err, doc) {
           assert.ifError(err);
           assert.ok(!('whateveriwant' in doc));
           done();
@@ -3771,9 +3771,9 @@ describe('Model', function() {
   });
 
   it('should not throw range error when using Number _id and saving existing doc (gh-691)', function(done) {
-    const T = new Schema({_id: Number, a: String});
+    const T = new Schema({ _id: Number, a: String });
     const D = db.model('Test', T);
-    const d = new D({_id: 1});
+    const d = new D({ _id: 1 });
     d.save(function(err) {
       assert.ifError(err);
 
@@ -3793,7 +3793,7 @@ describe('Model', function() {
     it('is saved (gh-742)', function(done) {
       const DefaultTestObject = db.model('Test',
         new Schema({
-          score: {type: Number, default: 55}
+          score: { type: Number, default: 55 }
         })
       );
 
@@ -3827,9 +3827,9 @@ describe('Model', function() {
   });
 
   it('path is cast to correct value when retreived from db', function(done) {
-    const schema = new Schema({title: {type: 'string', index: true}});
+    const schema = new Schema({ title: { type: 'string', index: true } });
     const T = db.model('Test', schema);
-    T.collection.insertOne({title: 234}, {safe: true}, function(err) {
+    T.collection.insertOne({ title: 234 }, { safe: true }, function(err) {
       assert.ifError(err);
       T.findOne(function(err, doc) {
         assert.ifError(err);
@@ -3853,8 +3853,8 @@ describe('Model', function() {
     doc.numbers = [3, 4, 5];
     doc.meta.date = new Date;
     doc.meta.visitors = 89;
-    doc.comments = [{title: 'thanksgiving', body: 'yuuuumm'}];
-    doc.comments.push({title: 'turkey', body: 'cranberries'});
+    doc.comments = [{ title: 'thanksgiving', body: 'yuuuumm' }];
+    doc.comments.push({ title: 'turkey', body: 'cranberries' });
 
     doc.save(function(err) {
       assert.ifError(err);
@@ -3893,7 +3893,7 @@ describe('Model', function() {
             b.comments = undefined;
             b.save(function(err) {
               assert.ifError(err);
-              B.collection.findOne({_id: b._id}, function(err, b) {
+              B.collection.findOne({ _id: b._id }, function(err, b) {
                 assert.ifError(err);
                 assert.strictEqual(undefined, b.meta);
                 assert.strictEqual(undefined, b.comments);
@@ -3908,8 +3908,8 @@ describe('Model', function() {
 
   describe('unsetting a default value', function() {
     it('should be ignored (gh-758)', function(done) {
-      const M = db.model('Test', new Schema({s: String, n: Number, a: Array}));
-      M.collection.insertOne({}, {safe: true}, function(err) {
+      const M = db.model('Test', new Schema({ s: String, n: Number, a: Array }));
+      M.collection.insertOne({}, { safe: true }, function(err) {
         assert.ifError(err);
         M.findOne(function(err, m) {
           assert.ifError(err);
@@ -3922,18 +3922,18 @@ describe('Model', function() {
   });
 
   it('allow for object passing to ref paths (gh-1606)', function(done) {
-    const schA = new Schema({title: String});
+    const schA = new Schema({ title: String });
     const schma = new Schema({
-      thing: {type: Schema.Types.ObjectId, ref: 'Test'},
+      thing: { type: Schema.Types.ObjectId, ref: 'Test' },
       subdoc: {
         some: String,
-        thing: [{type: Schema.Types.ObjectId, ref: 'Test'}]
+        thing: [{ type: Schema.Types.ObjectId, ref: 'Test' }]
       }
     });
 
     const M1 = db.model('Test', schA);
     const M2 = db.model('Test1', schma);
-    const a = new M1({title: 'hihihih'}).toObject();
+    const a = new M1({ title: 'hihihih' }).toObject();
     const thing = new M2({
       thing: a,
       subdoc: {
@@ -3962,7 +3962,7 @@ describe('Model', function() {
     });
 
     const Order = db.model('Test', OrderSchema);
-    const o = new Order({total: null});
+    const o = new Order({ total: null });
 
     assert.deepEqual(calls, [0, null]);
     assert.equal(o.total, 10);
@@ -4030,7 +4030,7 @@ describe('Model', function() {
 
     it('2dsphere indexed field in subdoc without value is saved', function() {
       const PersonSchema = new Schema({
-        name: {type: String, required: true},
+        name: { type: String, required: true },
         nested: {
           tag: String,
           loc: {
@@ -4039,7 +4039,7 @@ describe('Model', function() {
         }
       }, { autoIndex: false });
 
-      PersonSchema.index({'nested.loc': '2dsphere'});
+      PersonSchema.index({ 'nested.loc': '2dsphere' });
 
       const Person = db.model('Person', PersonSchema);
       const p = new Person({
@@ -4111,7 +4111,7 @@ describe('Model', function() {
           }
         };
 
-        const personDoc = yield Person.findByIdAndUpdate(p._id, updates, {new: true});
+        const personDoc = yield Person.findByIdAndUpdate(p._id, updates, { new: true });
 
         assert.equal(personDoc.loc[0], updates.$set.loc[0]);
         assert.equal(personDoc.loc[1], updates.$set.loc[1]);
@@ -4204,12 +4204,12 @@ describe('Model', function() {
       const PersonSchema = new Schema({
         name: String,
         type: String,
-        slug: {type: String, index: {unique: true}},
-        loc: {type: [Number]},
-        tags: {type: [String], index: true}
+        slug: { type: String, index: { unique: true } },
+        loc: { type: [Number] },
+        tags: { type: [String], index: true }
       }, { autoIndex: false });
 
-      PersonSchema.index({name: 1, loc: '2dsphere'});
+      PersonSchema.index({ name: 1, loc: '2dsphere' });
 
       const Person = db.model('Person', PersonSchema);
       const p = new Person({
@@ -4238,13 +4238,13 @@ describe('Model', function() {
       const PersonSchema = new Schema({
         name: String,
         type: String,
-        slug: {type: String, index: {unique: true}},
-        loc: {type: [Number]},
-        tags: {type: [String], index: true}
+        slug: { type: String, index: { unique: true } },
+        loc: { type: [Number] },
+        tags: { type: [String], index: true }
       }, { autoIndex: false });
 
-      PersonSchema.index({loc: '2dsphere'});
-      PersonSchema.index({name: 1, loc: -1});
+      PersonSchema.index({ loc: '2dsphere' });
+      PersonSchema.index({ name: 1, loc: -1 });
 
       const Person = db.model('Person', PersonSchema);
       const p = new Person({
@@ -4319,11 +4319,11 @@ describe('Model', function() {
       const Parent = db.model('Parent', parentSchema);
 
       const parent = new Parent();
-      parent.children.push({name: 'child name'});
+      parent.children.push({ name: 'child name' });
       parent.save(function(err, it) {
         assert.ifError(err);
-        parent.children.push({name: 'another child'});
-        Parent.findByIdAndUpdate(it._id, {$set: {children: parent.children}}, function(err) {
+        parent.children.push({ name: 'another child' });
+        Parent.findByIdAndUpdate(it._id, { $set: { children: parent.children } }, function(err) {
           assert.ifError(err);
           done();
         });
@@ -4838,7 +4838,7 @@ describe('Model', function() {
       });
 
       const Movie = db.model('Movie', schema);
-      const movie = new Movie({ title: 'Passengers'});
+      const movie = new Movie({ title: 'Passengers' });
       assert.equal(movie.actors.length, 2);
     });
 
@@ -5790,7 +5790,7 @@ describe('Model', function() {
     it('marks array as modified when initializing non-array from db (gh-2442)', function(done) {
       const s1 = new Schema({
         array: mongoose.Schema.Types.Mixed
-      }, {minimize: false});
+      }, { minimize: false });
 
       const s2 = new Schema({
         array: {
@@ -5808,16 +5808,16 @@ describe('Model', function() {
       const M1 = db.model('Test', s1);
       const M2 = db.model('Test1', s2, 'tests');
 
-      M1.create({array: {}}, function(err, doc) {
+      M1.create({ array: {} }, function(err, doc) {
         assert.ifError(err);
         assert.ok(doc.array);
-        M2.findOne({_id: doc._id}, function(err, doc) {
+        M2.findOne({ _id: doc._id }, function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.array[0].value, 0);
           doc.array[0].value = 1;
           doc.save(function(err) {
             assert.ifError(err);
-            M2.findOne({_id: doc._id}, function(err, doc) {
+            M2.findOne({ _id: doc._id }, function(err, doc) {
               assert.ifError(err);
               assert.ok(!doc.isModified('array'));
               assert.deepEqual(doc.array[0].value, 1);
@@ -6138,7 +6138,7 @@ describe('Model', function() {
       const indexes = yield Model.listIndexes();
 
       assert.equal(indexes.length, 2);
-      assert.deepEqual(indexes[1].key, { name: 1});
+      assert.deepEqual(indexes[1].key, { name: 1 });
     });
   });
 
diff --git a/test/model.translateAliases.test.js b/test/model.translateAliases.test.js
index a7807fa16e2..f55462045d2 100644
--- a/test/model.translateAliases.test.js
+++ b/test/model.translateAliases.test.js
@@ -31,7 +31,7 @@ describe('model translate aliases', function() {
         名: 'Stark',
         年齢: 30,
         'dot.syntax': 'DotSyntax',
-        $and: [{$or: [{名: 'Stark'}, {年齢: 30}]}, {'dot.syntax': 'DotSyntax'}]
+        $and: [{ $or: [{ 名: 'Stark' }, { 年齢: 30 }] }, { 'dot.syntax': 'DotSyntax' }]
       }),
       // How translated aliases suppose to look like
       {
@@ -39,7 +39,7 @@ describe('model translate aliases', function() {
         _id: '1',
         'bio.age': 30,
         'd.s': 'DotSyntax',
-        $and: [{$or: [{name: 'Stark'}, {'bio.age': 30}]}, {'d.s': 'DotSyntax'}]
+        $and: [{ $or: [{ name: 'Stark' }, { 'bio.age': 30 }] }, { 'd.s': 'DotSyntax' }]
       }
     );
 
diff --git a/test/model.update.test.js b/test/model.update.test.js
index d869c2b3270..17a7444346e 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -56,7 +56,7 @@ describe('model: update:', function() {
       numbers: [Number],
       owners: [ObjectId],
       comments: [Comments]
-    }, {strict: false});
+    }, { strict: false });
 
     schema.virtual('titleWithAuthor')
       .get(function() {
@@ -93,10 +93,10 @@ describe('model: update:', function() {
     post.meta.visitors = 0;
     post.date = new Date;
     post.published = true;
-    post.mixed = {x: 'ex'};
+    post.mixed = { x: 'ex' };
     post.numbers = [4, 5, 6, 7];
     post.owners = [id0, id1];
-    post.comments = [{body: 'been there'}, {body: 'done that'}];
+    post.comments = [{ body: 'been there' }, { body: 'done that' }];
 
     return post.save();
   });
@@ -128,16 +128,16 @@ describe('model: update:', function() {
 
       const update = {
         title: newTitle, // becomes $set
-        $inc: {'meta.visitors': 2},
-        $set: {date: new Date},
+        $inc: { 'meta.visitors': 2 },
+        $set: { date: new Date },
         published: false, // becomes $set
-        mixed: {x: 'ECKS', y: 'why'}, // $set
-        $pullAll: {numbers: [4, 6]},
-        $pull: {owners: id0},
+        mixed: { x: 'ECKS', y: 'why' }, // $set
+        $pullAll: { numbers: [4, 6] },
+        $pull: { owners: id0 },
         'comments.1.body': 8 // $set
       };
 
-      BlogPost.update({title: title}, update, function(err) {
+      BlogPost.update({ title: title }, update, function(err) {
         assert.ifError(err);
 
         BlogPost.findById(post._id, function(err, up) {
@@ -163,7 +163,7 @@ describe('model: update:', function() {
             'comments.body': 'fail'
           };
 
-          BlogPost.update({_id: post._id}, update2, function(err) {
+          BlogPost.update({ _id: post._id }, update2, function(err) {
             assert.ok(err);
             assert.ok(err.message.length > 0);
             BlogPost.findById(post, function(err) {
@@ -173,17 +173,17 @@ describe('model: update:', function() {
                 $pull: 'fail'
               };
 
-              BlogPost.update({_id: post._id}, update3, function(err) {
+              BlogPost.update({ _id: post._id }, update3, function(err) {
                 assert.ok(err);
 
                 assert.ok(/Invalid atomic update value for \$pull\. Expected an object, received string/.test(err.message));
 
                 const update4 = {
-                  $inc: {idontexist: 1}
+                  $inc: { idontexist: 1 }
                 };
 
                 // should not overwrite doc when no valid paths are submitted
-                BlogPost.update({_id: post._id}, update4, function(err) {
+                BlogPost.update({ _id: post._id }, update4, function(err) {
                   assert.ifError(err);
 
                   BlogPost.findById(post._id, function(err, up) {
@@ -217,16 +217,16 @@ describe('model: update:', function() {
 
   it('casts doc arrays', function(done) {
     const update = {
-      comments: [{body: 'worked great'}],
-      $set: {'numbers.1': 100},
-      $inc: {idontexist: 1}
+      comments: [{ body: 'worked great' }],
+      $set: { 'numbers.1': 100 },
+      $inc: { idontexist: 1 }
     };
 
-    BlogPost.update({_id: post._id}, update, function(err) {
+    BlogPost.update({ _id: post._id }, update, function(err) {
       assert.ifError(err);
 
       // get the underlying doc
-      BlogPost.collection.findOne({_id: post._id}, function(err, doc) {
+      BlogPost.collection.findOne({ _id: post._id }, function(err, doc) {
         assert.ifError(err);
 
         const up = new BlogPost;
@@ -241,8 +241,8 @@ describe('model: update:', function() {
   });
 
   it('makes copy of conditions and update options', function(done) {
-    const conditions = {_id: post._id.toString()};
-    const update = {$set: {some_attrib: post._id.toString()}};
+    const conditions = { _id: post._id.toString() };
+    const update = { $set: { some_attrib: post._id.toString() } };
     BlogPost.update(conditions, update, function(err) {
       assert.ifError(err);
       assert.equal(typeof conditions._id, 'string');
@@ -260,11 +260,11 @@ describe('model: update:', function() {
     const crazy = new a;
 
     const update = {
-      $addToSet: {'comments.$.comments': {body: 'The Ring Of Power'}},
-      $set: {'comments.$.title': crazy}
+      $addToSet: { 'comments.$.comments': { body: 'The Ring Of Power' } },
+      $set: { 'comments.$.title': crazy }
     };
 
-    BlogPost.update({_id: post._id, 'comments.body': 'been there'}, update, function(err) {
+    BlogPost.update({ _id: post._id, 'comments.body': 'been there' }, update, function(err) {
       assert.ifError(err);
       BlogPost.findById(post, function(err, ret) {
         assert.ifError(err);
@@ -292,11 +292,11 @@ describe('model: update:', function() {
 
     it('handles date casting (gh-479)', function(done) {
       const update = {
-        $inc: {'comments.$.newprop': '1'},
-        $set: {date: (new Date).getTime()} // check for single val casting
+        $inc: { 'comments.$.newprop': '1' },
+        $set: { date: (new Date).getTime() } // check for single val casting
       };
 
-      BlogPost.update({_id: post._id, 'comments.body': 'been there'}, update, function(err) {
+      BlogPost.update({ _id: post._id, 'comments.body': 'been there' }, update, function(err) {
         assert.ifError(err);
         BlogPost.findById(post, function(err, ret) {
           assert.ifError(err);
@@ -315,10 +315,10 @@ describe('model: update:', function() {
       assert.ok(owner);
       const numOwners = last.owners.length;
       const update = {
-        $addToSet: {owners: owner}
+        $addToSet: { owners: owner }
       };
 
-      BlogPost.update({_id: last._id}, update, function(err) {
+      BlogPost.update({ _id: last._id }, update, function(err) {
         assert.ifError(err);
         BlogPost.findById(last, function(err, ret) {
           assert.ifError(err);
@@ -336,10 +336,10 @@ describe('model: update:', function() {
       const numOwners = post.owners.length;
 
       const update = {
-        $addToSet: {owners: {$each: [owner, newowner]}}
+        $addToSet: { owners: { $each: [owner, newowner] } }
       };
 
-      BlogPost.update({_id: post._id}, update, function(err) {
+      BlogPost.update({ _id: post._id }, update, function(err) {
         assert.ifError(err);
         BlogPost.findById(post, function(err, ret) {
           assert.ifError(err);
@@ -354,11 +354,11 @@ describe('model: update:', function() {
 
     it('handles $pop and $unset (gh-574)', function(done) {
       const update = {
-        $pop: {owners: -1},
-        $unset: {title: 1}
+        $pop: { owners: -1 },
+        $unset: { title: 1 }
       };
 
-      BlogPost.update({_id: post._id}, update, function(err) {
+      BlogPost.update({ _id: post._id }, update, function(err) {
         assert.ifError(err);
         BlogPost.findById(post, function(err, ret) {
           assert.ifError(err);
@@ -380,7 +380,7 @@ describe('model: update:', function() {
       }
     };
 
-    BlogPost.update({_id: post._id}, update, function(err) {
+    BlogPost.update({ _id: post._id }, update, function(err) {
       assert.ifError(err);
       BlogPost.findById(post, function(err, ret) {
         assert.ifError(err);
@@ -399,10 +399,10 @@ describe('model: update:', function() {
       assert.ifError(err);
 
       const update = {
-        $pull: {comments: {_id: doc.comments[0].id}}
+        $pull: { comments: { _id: doc.comments[0].id } }
       };
 
-      BlogPost.update({_id: post._id}, update, function(err) {
+      BlogPost.update({ _id: post._id }, update, function(err) {
         assert.ifError(err);
         BlogPost.findById(post, function(err, ret) {
           assert.ifError(err);
@@ -416,10 +416,10 @@ describe('model: update:', function() {
 
   it('handles $pull of obj literal and nested $in', function(done) {
     const update = {
-      $pull: {comments: {body: {$in: ['been there']}}}
+      $pull: { comments: { body: { $in: ['been there'] } } }
     };
 
-    BlogPost.update({_id: post._id}, update, function(err) {
+    BlogPost.update({ _id: post._id }, update, function(err) {
       assert.ifError(err);
       BlogPost.findById(post, function(err, ret) {
         assert.ifError(err);
@@ -435,7 +435,7 @@ describe('model: update:', function() {
     BlogPost.findById(post, function(err, doc) {
       assert.ifError(err);
 
-      doc.comments.push({body: 'hi'}, {body: 'there'});
+      doc.comments.push({ body: 'hi' }, { body: 'there' });
       doc.save(function(err) {
         assert.ifError(err);
         BlogPost.findById(doc, function(err, ret) {
@@ -443,10 +443,10 @@ describe('model: update:', function() {
           assert.equal(ret.comments.length, 4);
 
           const update = {
-            $pull: {comments: {body: {$nin: ['there']}}}
+            $pull: { comments: { body: { $nin: ['there'] } } }
           };
 
-          BlogPost.update({_id: ret._id}, update, function(err) {
+          BlogPost.update({ _id: ret._id }, update, function(err) {
             assert.ifError(err);
             BlogPost.findById(post, function(err, ret) {
               assert.ifError(err);
@@ -467,7 +467,7 @@ describe('model: update:', function() {
     post.set('meta.visitors', 5);
 
     function complete() {
-      BlogPost.findOne({_id: post.get('_id')}, function(err, doc) {
+      BlogPost.findOne({ _id: post.get('_id') }, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.get('meta.visitors'), 9);
         done();
@@ -482,7 +482,7 @@ describe('model: update:', function() {
       }
       for (let i = 0; i < 4; ++i) {
         BlogPost
-          .update({_id: post._id}, {$inc: {'meta.visitors': 1}}, callback);
+          .update({ _id: post._id }, { $inc: { 'meta.visitors': 1 } }, callback);
       }
     });
   });
@@ -490,23 +490,23 @@ describe('model: update:', function() {
   it('passes number of affected docs', function() {
     return co(function*() {
       yield BlogPost.deleteMany({});
-      yield BlogPost.create({title: 'one'}, {title: 'two'}, {title: 'three'});
+      yield BlogPost.create({ title: 'one' }, { title: 'two' }, { title: 'three' });
 
-      const res = yield BlogPost.update({}, {title: 'newtitle'}, {multi: true});
+      const res = yield BlogPost.update({}, { title: 'newtitle' }, { multi: true });
       assert.equal(res.n, 3);
     });
   });
 
   it('updates a number to null (gh-640)', function(done) {
     const B = BlogPost;
-    const b = new B({meta: {visitors: null}});
+    const b = new B({ meta: { visitors: null } });
     b.save(function(err) {
       assert.ifError(err);
       B.findById(b, function(err, b) {
         assert.ifError(err);
         assert.strictEqual(b.meta.visitors, null);
 
-        B.update({_id: b._id}, {meta: {visitors: null}}, function(err) {
+        B.update({ _id: b._id }, { meta: { visitors: null } }, function(err) {
           assert.strictEqual(null, err);
           done();
         });
@@ -515,11 +515,11 @@ describe('model: update:', function() {
   });
 
   it('handles $pull from Mixed arrays (gh-735)', function(done) {
-    const schema = new Schema({comments: []});
+    const schema = new Schema({ comments: [] });
     const M = db.model('Test', schema);
-    M.create({comments: [{name: 'node 0.8'}]}, function(err, doc) {
+    M.create({ comments: [{ name: 'node 0.8' }] }, function(err, doc) {
       assert.ifError(err);
-      M.update({_id: doc._id}, {$pull: {comments: {name: 'node 0.8'}}}, function(err, affected) {
+      M.update({ _id: doc._id }, { $pull: { comments: { name: 'node 0.8' } } }, function(err, affected) {
         assert.ifError(err);
         assert.equal(affected.n, 1);
         done();
@@ -544,14 +544,14 @@ describe('model: update:', function() {
 
     const Project = db.model('Test', projectSchema);
 
-    Project.create({name: 'my project'}, function(err, project) {
+    Project.create({ name: 'my project' }, function(err, project) {
       assert.ifError(err);
       const pid = project.id;
-      const comp = project.components.create({name: 'component'});
-      Project.update({_id: pid}, {$push: {components: comp}}, function(err) {
+      const comp = project.components.create({ name: 'component' });
+      Project.update({ _id: pid }, { $push: { components: comp } }, function(err) {
         assert.ifError(err);
-        const task = comp.tasks.create({name: 'my task'});
-        Project.update({_id: pid, 'components._id': comp._id}, {$push: {'components.$.tasks': task}}, function(err) {
+        const task = comp.tasks.create({ name: 'my task' });
+        Project.update({ _id: pid, 'components._id': comp._id }, { $push: { 'components.$.tasks': task } }, function(err) {
           assert.ifError(err);
           Project.findById(pid, function(err, proj) {
             assert.ifError(err);
@@ -570,11 +570,11 @@ describe('model: update:', function() {
   });
 
   it('handles nested paths starting with numbers (gh-1062)', function(done) {
-    const schema = new Schema({counts: Schema.Types.Mixed});
+    const schema = new Schema({ counts: Schema.Types.Mixed });
     const M = db.model('Test', schema);
-    M.create({counts: {}}, function(err, m) {
+    M.create({ counts: {} }, function(err, m) {
       assert.ifError(err);
-      M.update({}, {$inc: {'counts.1': 1, 'counts.1a': 10}}, function(err) {
+      M.update({}, { $inc: { 'counts.1': 1, 'counts.1a': 10 } }, function(err) {
         assert.ifError(err);
         M.findById(m, function(err, doc) {
           assert.ifError(err);
@@ -587,13 +587,13 @@ describe('model: update:', function() {
   });
 
   it('handles positional operators with referenced docs (gh-1572)', function(done) {
-    const so = new Schema({title: String, obj: [String]});
+    const so = new Schema({ title: String, obj: [String] });
     const Some = db.model('Test', so);
 
-    Some.create({obj: ['a', 'b', 'c']}, function(err, s) {
+    Some.create({ obj: ['a', 'b', 'c'] }, function(err, s) {
       assert.ifError(err);
 
-      Some.update({_id: s._id, obj: 'b'}, {$set: {'obj.$': 2}}, function(err) {
+      Some.update({ _id: s._id, obj: 'b' }, { $set: { 'obj.$': 2 } }, function(err) {
         assert.ifError(err);
 
         Some.findById(s._id, function(err, ss) {
@@ -607,17 +607,17 @@ describe('model: update:', function() {
   });
 
   it('use .where for update condition (gh-2170)', function(done) {
-    const so = new Schema({num: Number});
+    const so = new Schema({ num: Number });
     const Some = db.model('Test', so);
 
-    Some.create([{num: 1}, {num: 1}], function(err, docs) {
+    Some.create([{ num: 1 }, { num: 1 }], function(err, docs) {
       assert.ifError(err);
       assert.equal(docs.length, 2);
       const doc0 = docs[0];
       const doc1 = docs[1];
       const sId0 = doc0._id;
       const sId1 = doc1._id;
-      Some.where({_id: sId0}).update({}, {$set: {num: '99'}}, {multi: true}, function(err, cnt) {
+      Some.where({ _id: sId0 }).update({}, { $set: { num: '99' } }, { multi: true }, function(err, cnt) {
         assert.ifError(err);
         assert.equal(cnt.n, 1);
         Some.findById(sId0, function(err, doc0_1) {
@@ -650,21 +650,21 @@ describe('model: update:', function() {
         return done();
       }
 
-      const schema = new Schema({name: String, age: Number, x: String});
+      const schema = new Schema({ name: String, age: Number, x: String });
       const M = db.model('Test', schema);
 
-      const match = {name: 'set on insert'};
-      const op = {$setOnInsert: {age: '47'}, x: 'inserted'};
-      M.update(match, op, {upsert: true}, function(err) {
+      const match = { name: 'set on insert' };
+      const op = { $setOnInsert: { age: '47' }, x: 'inserted' };
+      M.update(match, op, { upsert: true }, function(err) {
         assert.ifError(err);
         M.findOne(function(err, doc) {
           assert.ifError(err);
           assert.equal(doc.age, 47);
           assert.equal(doc.name, 'set on insert');
 
-          const match = {name: 'set on insert'};
-          const op = {$setOnInsert: {age: 108}, name: 'changed'};
-          M.update(match, op, {upsert: true}, function(err) {
+          const match = { name: 'set on insert' };
+          const op = { $setOnInsert: { age: 108 }, name: 'changed' };
+          M.update(match, op, { upsert: true }, function(err) {
             assert.ifError(err);
 
             M.findOne(function(err, doc) {
@@ -683,23 +683,23 @@ describe('model: update:', function() {
         return done();
       }
 
-      const schema = new Schema({name: String, n: [{x: Number}]});
+      const schema = new Schema({ name: String, n: [{ x: Number }] });
       const M = db.model('Test', schema);
 
-      M.create({name: '2.4'}, function(err, created) {
+      M.create({ name: '2.4' }, function(err, created) {
         assert.ifError(err);
 
         let op = {
           $push: {
             n: {
-              $each: [{x: 10}, {x: 4}, {x: 1}],
+              $each: [{ x: 10 }, { x: 4 }, { x: 1 }],
               $slice: '-1',
-              $sort: {x: 1}
+              $sort: { x: 1 }
             }
           }
         };
 
-        M.update({_id: created._id}, op, function(err) {
+        M.update({ _id: created._id }, op, function(err) {
           assert.ifError(err);
           M.findById(created._id, function(err, doc) {
             assert.ifError(err);
@@ -715,7 +715,7 @@ describe('model: update:', function() {
                 }
               }
             };
-            M.update({_id: created._id}, op, function(err) {
+            M.update({ _id: created._id }, op, function(err) {
               assert.ifError(err);
               M.findById(created._id, function(error, doc) {
                 assert.ifError(error);
@@ -745,19 +745,19 @@ describe('model: update:', function() {
         return done();
       }
 
-      const schema = new Schema({name: String, n: [{x: Number}]});
+      const schema = new Schema({ name: String, n: [{ x: Number }] });
       const M = db.model('Test', schema);
 
-      const m = new M({name: '2.6', n: [{x: 0}]});
+      const m = new M({ name: '2.6', n: [{ x: 0 }] });
       m.save(function(error, m) {
         assert.ifError(error);
         assert.equal(m.n.length, 1);
         M.updateOne(
-          {name: '2.6'},
-          {$push: {n: {$each: [{x: 2}, {x: 1}], $position: 0}}},
+          { name: '2.6' },
+          { $push: { n: { $each: [{ x: 2 }, { x: 1 }], $position: 0 } } },
           function(error) {
             assert.ifError(error);
-            M.findOne({name: '2.6'}, function(error, m) {
+            M.findOne({ name: '2.6' }, function(error, m) {
               assert.ifError(error);
               assert.equal(m.n.length, 3);
               assert.equal(m.n[0].x, 2);
@@ -774,19 +774,19 @@ describe('model: update:', function() {
         return done();
       }
 
-      const schema = new Schema({name: String, lastModified: Date, lastModifiedTS: Date});
+      const schema = new Schema({ name: String, lastModified: Date, lastModifiedTS: Date });
       const M = db.model('Test', schema);
 
-      const m = new M({name: '2.6'});
+      const m = new M({ name: '2.6' });
       m.save(function(error) {
         assert.ifError(error);
         const before = Date.now();
         M.update(
-          {name: '2.6'},
-          {$currentDate: {lastModified: true, lastModifiedTS: {$type: 'timestamp'}}},
+          { name: '2.6' },
+          { $currentDate: { lastModified: true, lastModifiedTS: { $type: 'timestamp' } } },
           function(error) {
             assert.ifError(error);
-            M.findOne({name: '2.6'}, function(error, m) {
+            M.findOne({ name: '2.6' }, function(error, m) {
               const after = Date.now();
               assert.ifError(error);
               assert.ok(m.lastModified.getTime() >= before);
@@ -800,13 +800,13 @@ describe('model: update:', function() {
 
   describe('{overwrite: true}', function() {
     it('overwrite works', function(done) {
-      const schema = new Schema({mixed: {}}, { minimize: false });
+      const schema = new Schema({ mixed: {} }, { minimize: false });
       const M = db.model('Test', schema);
 
-      M.create({mixed: 'something'}, function(err, created) {
+      M.create({ mixed: 'something' }, function(err, created) {
         assert.ifError(err);
 
-        M.update({_id: created._id}, {mixed: {}}, {overwrite: true}, function(err) {
+        M.update({ _id: created._id }, { mixed: {} }, { overwrite: true }, function(err) {
           assert.ifError(err);
           M.findById(created._id, function(err, doc) {
             assert.ifError(err);
@@ -820,14 +820,14 @@ describe('model: update:', function() {
     });
 
     it('overwrites all properties', function(done) {
-      const sch = new Schema({title: String, subdoc: {name: String, num: Number}});
+      const sch = new Schema({ title: String, subdoc: { name: String, num: Number } });
 
       const M = db.model('Test', sch);
 
-      M.create({subdoc: {name: 'that', num: 1}}, function(err, doc) {
+      M.create({ subdoc: { name: 'that', num: 1 } }, function(err, doc) {
         assert.ifError(err);
 
-        M.update({_id: doc.id}, {title: 'something!'}, {overwrite: true}, function(err) {
+        M.update({ _id: doc.id }, { title: 'something!' }, { overwrite: true }, function(err) {
           assert.ifError(err);
           M.findById(doc.id, function(err, doc) {
             assert.ifError(err);
@@ -841,14 +841,14 @@ describe('model: update:', function() {
     });
 
     it('allows users to blow it up', function(done) {
-      const sch = new Schema({title: String, subdoc: {name: String, num: Number}});
+      const sch = new Schema({ title: String, subdoc: { name: String, num: Number } });
 
       const M = db.model('Test', sch);
 
-      M.create({subdoc: {name: 'that', num: 1, title: 'hello'}}, function(err, doc) {
+      M.create({ subdoc: { name: 'that', num: 1, title: 'hello' } }, function(err, doc) {
         assert.ifError(err);
 
-        M.update({_id: doc.id}, {}, {overwrite: true}, function(err) {
+        M.update({ _id: doc.id }, {}, { overwrite: true }, function(err) {
           assert.ifError(err);
           M.findById(doc.id, function(err, doc) {
             assert.ifError(err);
@@ -863,15 +863,15 @@ describe('model: update:', function() {
   });
 
   it('casts empty arrays', function(done) {
-    const so = new Schema({arr: []});
+    const so = new Schema({ arr: [] });
     const Some = db.model('Test', so);
 
-    Some.create({arr: ['a']}, function(err, s) {
+    Some.create({ arr: ['a'] }, function(err, s) {
       if (err) {
         return done(err);
       }
 
-      Some.update({_id: s._id}, {arr: []}, function(err) {
+      Some.update({ _id: s._id }, { arr: [] }, function(err) {
         if (err) {
           return done(err);
         }
@@ -889,10 +889,10 @@ describe('model: update:', function() {
 
   describe('defaults and validators (gh-860)', function() {
     it('applies defaults on upsert', function(done) {
-      const s = new Schema({topping: {type: String, default: 'bacon'}, base: String});
+      const s = new Schema({ topping: { type: String, default: 'bacon' }, base: String });
       const Breakfast = db.model('Test', s);
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true};
-      Breakfast.update({}, {base: 'eggs'}, updateOptions, function(error) {
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true };
+      Breakfast.update({}, { base: 'eggs' }, updateOptions, function(error) {
         assert.ifError(error);
         Breakfast.findOne({}).lean().exec(function(error, breakfast) {
           assert.ifError(error);
@@ -928,11 +928,11 @@ describe('model: update:', function() {
     });
 
     it('doesnt set default on upsert if query sets it', function(done) {
-      const s = new Schema({topping: {type: String, default: 'bacon'}, base: String});
+      const s = new Schema({ topping: { type: String, default: 'bacon' }, base: String });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true};
-      Breakfast.update({topping: 'sausage'}, {base: 'eggs'}, updateOptions, function(error) {
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true };
+      Breakfast.update({ topping: 'sausage' }, { base: 'eggs' }, updateOptions, function(error) {
         assert.ifError(error);
         Breakfast.findOne({}, function(error, breakfast) {
           assert.ifError(error);
@@ -944,11 +944,11 @@ describe('model: update:', function() {
     });
 
     it('properly sets default on upsert if query wont set it', function(done) {
-      const s = new Schema({topping: {type: String, default: 'bacon'}, base: String});
+      const s = new Schema({ topping: { type: String, default: 'bacon' }, base: String });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true};
-      Breakfast.update({topping: {$ne: 'sausage'}}, {base: 'eggs'}, updateOptions, function(error) {
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true };
+      Breakfast.update({ topping: { $ne: 'sausage' } }, { base: 'eggs' }, updateOptions, function(error) {
         assert.ifError(error);
         Breakfast.findOne({}, function(error, breakfast) {
           assert.ifError(error);
@@ -1018,8 +1018,8 @@ describe('model: update:', function() {
       });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {upsert: true, setDefaultsOnInsert: true, runValidators: true};
-      Breakfast.update({}, {topping: 'bacon', base: 'eggs'}, updateOptions, function(error) {
+      const updateOptions = { upsert: true, setDefaultsOnInsert: true, runValidators: true };
+      Breakfast.update({}, { topping: 'bacon', base: 'eggs' }, updateOptions, function(error) {
         assert.ok(!!error);
         assert.equal(Object.keys(error.errors).length, 1);
         assert.equal(Object.keys(error.errors)[0], 'topping');
@@ -1035,7 +1035,7 @@ describe('model: update:', function() {
 
     it('validators handle $unset and $setOnInsert', function(done) {
       const s = new Schema({
-        steak: {type: String, required: true},
+        steak: { type: String, required: true },
         eggs: {
           type: String,
           validate: function() {
@@ -1046,8 +1046,8 @@ describe('model: update:', function() {
       });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {runValidators: true, context: 'query'};
-      Breakfast.update({}, {$unset: {steak: ''}, $setOnInsert: {eggs: 'softboiled'}}, updateOptions, function(error) {
+      const updateOptions = { runValidators: true, context: 'query' };
+      Breakfast.update({}, { $unset: { steak: '' }, $setOnInsert: { eggs: 'softboiled' } }, updateOptions, function(error) {
         assert.ok(!!error);
         assert.equal(Object.keys(error.errors).length, 2);
         assert.ok(Object.keys(error.errors).indexOf('eggs') !== -1);
@@ -1079,26 +1079,26 @@ describe('model: update:', function() {
 
     it('min/max, enum, and regex built-in validators work', function(done) {
       const s = new Schema({
-        steak: {type: String, enum: ['ribeye', 'sirloin']},
-        eggs: {type: Number, min: 4, max: 6},
-        bacon: {type: String, match: /strips/}
+        steak: { type: String, enum: ['ribeye', 'sirloin'] },
+        eggs: { type: Number, min: 4, max: 6 },
+        bacon: { type: String, match: /strips/ }
       });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {runValidators: true};
-      Breakfast.update({}, {$set: {steak: 'ribeye', eggs: 3, bacon: '3 strips'}}, updateOptions, function(error) {
+      const updateOptions = { runValidators: true };
+      Breakfast.update({}, { $set: { steak: 'ribeye', eggs: 3, bacon: '3 strips' } }, updateOptions, function(error) {
         assert.ok(!!error);
         assert.equal(Object.keys(error.errors).length, 1);
         assert.equal(Object.keys(error.errors)[0], 'eggs');
         assert.equal(error.errors.eggs.message, 'Path `eggs` (3) is less than minimum allowed value (4).');
 
-        Breakfast.update({}, {$set: {steak: 'tofu', eggs: 5, bacon: '3 strips'}}, updateOptions, function(error) {
+        Breakfast.update({}, { $set: { steak: 'tofu', eggs: 5, bacon: '3 strips' } }, updateOptions, function(error) {
           assert.ok(!!error);
           assert.equal(Object.keys(error.errors).length, 1);
           assert.equal(Object.keys(error.errors)[0], 'steak');
           assert.equal(error.errors.steak, '`tofu` is not a valid enum value for path `steak`.');
 
-          Breakfast.update({}, {$set: {steak: 'sirloin', eggs: 6, bacon: 'none'}}, updateOptions, function(error) {
+          Breakfast.update({}, { $set: { steak: 'sirloin', eggs: 6, bacon: 'none' } }, updateOptions, function(error) {
             assert.ok(!!error);
             assert.equal(Object.keys(error.errors).length, 1);
             assert.equal(Object.keys(error.errors)[0], 'bacon');
@@ -1112,14 +1112,14 @@ describe('model: update:', function() {
 
     it('multiple validation errors', function(done) {
       const s = new Schema({
-        steak: {type: String, enum: ['ribeye', 'sirloin']},
-        eggs: {type: Number, min: 4, max: 6},
-        bacon: {type: String, match: /strips/}
+        steak: { type: String, enum: ['ribeye', 'sirloin'] },
+        eggs: { type: Number, min: 4, max: 6 },
+        bacon: { type: String, match: /strips/ }
       });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {runValidators: true};
-      Breakfast.update({}, {$set: {steak: 'tofu', eggs: 2, bacon: '3 strips'}}, updateOptions, function(error) {
+      const updateOptions = { runValidators: true };
+      Breakfast.update({}, { $set: { steak: 'tofu', eggs: 2, bacon: '3 strips' } }, updateOptions, function(error) {
         assert.ok(!!error);
         assert.equal(Object.keys(error.errors).length, 2);
         assert.ok(Object.keys(error.errors).indexOf('steak') !== -1);
@@ -1130,13 +1130,13 @@ describe('model: update:', function() {
 
     it('validators ignore $inc', function(done) {
       const s = new Schema({
-        steak: {type: String, required: true},
-        eggs: {type: Number, min: 4}
+        steak: { type: String, required: true },
+        eggs: { type: Number, min: 4 }
       });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {runValidators: true};
-      Breakfast.update({}, {$inc: {eggs: 1}}, updateOptions, function(error) {
+      const updateOptions = { runValidators: true };
+      Breakfast.update({}, { $inc: { eggs: 1 } }, updateOptions, function(error) {
         assert.ifError(error);
         done();
       });
@@ -1144,14 +1144,14 @@ describe('model: update:', function() {
 
     it('validators handle positional operator (gh-3167)', function(done) {
       const s = new Schema({
-        toppings: [{name: {type: String, enum: ['bacon', 'cheese']}}]
+        toppings: [{ name: { type: String, enum: ['bacon', 'cheese'] } }]
       });
       const Breakfast = db.model('Test', s);
 
-      const updateOptions = {runValidators: true};
+      const updateOptions = { runValidators: true };
       Breakfast.update(
-        {'toppings.name': 'bacon'},
-        {'toppings.$.name': 'tofu'},
+        { 'toppings.name': 'bacon' },
+        { 'toppings.$.name': 'tofu' },
         updateOptions,
         function(error) {
           assert.ok(error);
@@ -1162,7 +1162,7 @@ describe('model: update:', function() {
 
     it('validators handle arrayFilters (gh-7536)', function() {
       const s = new Schema({
-        toppings: [{name: {type: String, enum: ['bacon', 'cheese']}}]
+        toppings: [{ name: { type: String, enum: ['bacon', 'cheese'] } }]
       });
       const Breakfast = db.model('Test', s);
 
@@ -1171,7 +1171,7 @@ describe('model: update:', function() {
         arrayFilters: [{ 't.name': 'bacon' }]
       };
       return Breakfast.
-        update({}, {'toppings.$[t].name': 'tofu'}, updateOptions).
+        update({}, { 'toppings.$[t].name': 'tofu' }, updateOptions).
         then(
           () => assert.ok(false),
           err => {
@@ -1206,18 +1206,18 @@ describe('model: update:', function() {
   });
 
   it('works with $set and overwrite (gh-2515)', function(done) {
-    const schema = new Schema({breakfast: String});
+    const schema = new Schema({ breakfast: String });
     const M = db.model('Test', schema);
 
-    M.create({breakfast: 'bacon'}, function(error, doc) {
+    M.create({ breakfast: 'bacon' }, function(error, doc) {
       assert.ifError(error);
       M.update(
-        {_id: doc._id},
-        {$set: {breakfast: 'eggs'}},
-        {overwrite: true},
+        { _id: doc._id },
+        { $set: { breakfast: 'eggs' } },
+        { overwrite: true },
         function(error) {
           assert.ifError(error);
-          M.findOne({_id: doc._id}, function(error, doc) {
+          M.findOne({ _id: doc._id }, function(error, doc) {
             assert.ifError(error);
             assert.equal(doc.breakfast, 'eggs');
             done();
@@ -1227,19 +1227,19 @@ describe('model: update:', function() {
   });
 
   it('successfully casts set with nested mixed objects (gh-2796)', function(done) {
-    const schema = new Schema({breakfast: {}});
+    const schema = new Schema({ breakfast: {} });
     const M = db.model('Test', schema);
 
     M.create({}, function(error, doc) {
       assert.ifError(error);
       M.update(
-        {_id: doc._id},
-        {breakfast: {eggs: 2, bacon: 3}},
+        { _id: doc._id },
+        { breakfast: { eggs: 2, bacon: 3 } },
         function(error, result) {
           assert.ifError(error);
           assert.ok(result.ok);
           assert.equal(result.n, 1);
-          M.findOne({_id: doc._id}, function(error, doc) {
+          M.findOne({ _id: doc._id }, function(error, doc) {
             assert.ifError(error);
             assert.equal(doc.breakfast.eggs, 2);
             done();
@@ -1249,12 +1249,12 @@ describe('model: update:', function() {
   });
 
   it('handles empty update with promises (gh-2796)', function(done) {
-    const schema = new Schema({eggs: Number});
+    const schema = new Schema({ eggs: Number });
     const M = db.model('Test', schema);
 
     M.create({}, function(error, doc) {
       assert.ifError(error);
-      M.update({_id: doc._id}, {notInSchema: 1}).exec().
+      M.update({ _id: doc._id }, { notInSchema: 1 }).exec().
         then(function(data) {
           assert.equal(data.ok, 0);
           assert.equal(data.n, 0);
@@ -1268,7 +1268,7 @@ describe('model: update:', function() {
     it('can specify pre and post hooks', function(done) {
       let numPres = 0;
       let numPosts = 0;
-      const band = new Schema({members: [String]});
+      const band = new Schema({ members: [String] });
       band.pre('update', function(next) {
         ++numPres;
         next();
@@ -1278,19 +1278,19 @@ describe('model: update:', function() {
       });
       const Band = db.model('Band', band);
 
-      const gnr = new Band({members: ['Axl', 'Slash', 'Izzy', 'Duff', 'Adler']});
+      const gnr = new Band({ members: ['Axl', 'Slash', 'Izzy', 'Duff', 'Adler'] });
       gnr.save(function(error) {
         assert.ifError(error);
         assert.equal(numPres, 0);
         assert.equal(numPosts, 0);
         Band.update(
-          {_id: gnr._id},
-          {$pull: {members: 'Adler'}},
+          { _id: gnr._id },
+          { $pull: { members: 'Adler' } },
           function(error) {
             assert.ifError(error);
             assert.equal(numPres, 1);
             assert.equal(numPosts, 1);
-            Band.findOne({_id: gnr._id}, function(error, doc) {
+            Band.findOne({ _id: gnr._id }, function(error, doc) {
               assert.ifError(error);
               assert.deepEqual(['Axl', 'Slash', 'Izzy', 'Duff'],
                 doc.toObject().members);
@@ -1302,14 +1302,14 @@ describe('model: update:', function() {
 
     it('runs before validators (gh-2706)', function(done) {
       const bandSchema = new Schema({
-        lead: {type: String, enum: ['Axl Rose']}
+        lead: { type: String, enum: ['Axl Rose'] }
       });
       bandSchema.pre('update', function() {
         this.options.runValidators = true;
       });
       const Band = db.model('Band', bandSchema);
 
-      Band.update({}, {$set: {lead: 'Not Axl'}}, function(err) {
+      Band.update({}, { $set: { lead: 'Not Axl' } }, function(err) {
         assert.ok(err);
         done();
       });
@@ -1319,8 +1319,8 @@ describe('model: update:', function() {
       it('embedded objects (gh-2706)', function(done) {
         const bandSchema = new Schema({
           singer: {
-            firstName: {type: String, enum: ['Axl']},
-            lastName: {type: String, enum: ['Rose']}
+            firstName: { type: String, enum: ['Axl'] },
+            lastName: { type: String, enum: ['Rose'] }
           }
         });
         bandSchema.pre('update', function() {
@@ -1328,7 +1328,7 @@ describe('model: update:', function() {
         });
         const Band = db.model('Band', bandSchema);
 
-        Band.update({}, {$set: {singer: {firstName: 'Not', lastName: 'Axl'}}}, function(err) {
+        Band.update({}, { $set: { singer: { firstName: 'Not', lastName: 'Axl' } } }, function(err) {
           assert.ok(err);
           done();
         });
@@ -1337,20 +1337,20 @@ describe('model: update:', function() {
       it('handles document array validation (gh-2733)', function(done) {
         const member = new Schema({
           name: String,
-          role: {type: String, required: true, enum: ['singer', 'guitar', 'drums', 'bass']}
+          role: { type: String, required: true, enum: ['singer', 'guitar', 'drums', 'bass'] }
         });
-        const band = new Schema({members: [member], name: String});
+        const band = new Schema({ members: [member], name: String });
         const Band = db.model('Band', band);
         const members = [
-          {name: 'Axl Rose', role: 'singer'},
-          {name: 'Slash', role: 'guitar'},
-          {name: 'Christopher Walken', role: 'cowbell'}
+          { name: 'Axl Rose', role: 'singer' },
+          { name: 'Slash', role: 'guitar' },
+          { name: 'Christopher Walken', role: 'cowbell' }
         ];
 
         Band.findOneAndUpdate(
-          {name: 'Guns N\' Roses'},
-          {$set: {members: members}},
-          {runValidators: true},
+          { name: 'Guns N\' Roses' },
+          { $set: { members: members } },
+          { runValidators: true },
           function(err) {
             assert.ok(err);
             done();
@@ -1367,8 +1367,8 @@ describe('model: update:', function() {
         });
 
         const M = db.model('Test', schema);
-        const options = {runValidators: true};
-        M.findOneAndUpdate({}, {arr: ['test']}, options, function(error) {
+        const options = { runValidators: true };
+        M.findOneAndUpdate({}, { arr: ['test'] }, options, function(error) {
           assert.ok(error);
           assert.ok(/ValidationError/.test(error.toString()));
           done();
@@ -1390,16 +1390,16 @@ describe('model: update:', function() {
     const Book = db.model('Book', bookSchema);
 
     const jsonObject = {
-      chapters: [{name: 'Ursus'}, {name: 'The Comprachicos'}],
+      chapters: [{ name: 'Ursus' }, { name: 'The Comprachicos' }],
       name: 'The Man Who Laughs',
       author: 'Victor Hugo',
       id: 0
     };
 
-    Book.update({}, jsonObject, {upsert: true, overwrite: true},
+    Book.update({}, jsonObject, { upsert: true, overwrite: true },
       function(error) {
         assert.ifError(error);
-        Book.findOne({id: 0}, function(error, book) {
+        Book.findOne({ id: 0 }, function(error, book) {
           assert.ifError(error);
           assert.equal(book.chapters.length, 2);
           assert.ok(book.chapters[0]._id);
@@ -1416,7 +1416,7 @@ describe('model: update:', function() {
     const D = db.model('Test', dateSchema);
 
     assert.doesNotThrow(function() {
-      D.update({}, {d: undefined}, function() {
+      D.update({}, { d: undefined }, function() {
         done();
       });
     });
@@ -1455,8 +1455,8 @@ describe('model: update:', function() {
   });
 
   it('does not add virtuals to update (gh-2046)', function(done) {
-    const childSchema = new Schema({foo: String}, {toObject: {getters: true}});
-    const parentSchema = new Schema({children: [childSchema]});
+    const childSchema = new Schema({ foo: String }, { toObject: { getters: true } });
+    const parentSchema = new Schema({ children: [childSchema] });
 
     childSchema.virtual('bar').get(function() {
       return 'bar';
@@ -1464,7 +1464,7 @@ describe('model: update:', function() {
 
     const Parent = db.model('Parent', parentSchema);
 
-    const update = Parent.update({}, {$push: {children: {foo: 'foo'}}}, {upsert: true});
+    const update = Parent.update({}, { $push: { children: { foo: 'foo' } } }, { upsert: true });
     assert.equal(update._update.$push.children.bar, undefined);
 
     update.exec(function(error) {
@@ -1485,8 +1485,8 @@ describe('model: update:', function() {
     });
     const Model = db.model('Test', FooSchema);
 
-    const update = {$set: {values: 2, value: 2}};
-    Model.update({key: 1}, update, function() {
+    const update = { $set: { values: 2, value: 2 } };
+    Model.update({ key: 1 }, update, function() {
       assert.equal(update.$set.values, 2);
       done();
     });
@@ -1497,7 +1497,7 @@ describe('model: update:', function() {
       const schema = new Schema({ foo: Date, bar: Date });
       const Model = db.model('Test', schema);
 
-      const update = { $rename: { foo: 'bar'} };
+      const update = { $rename: { foo: 'bar' } };
       Model.create({ foo: Date.now() }, function(error) {
         assert.ifError(error);
         Model.update({}, update, { multi: true }, function(error, res) {
@@ -1510,15 +1510,15 @@ describe('model: update:', function() {
     });
 
     it('allows objects with positional operator (gh-3185)', function(done) {
-      const schema = new Schema({children: [{_id: Number}]});
+      const schema = new Schema({ children: [{ _id: Number }] });
       const MyModel = db.model('Test', schema);
 
-      MyModel.create({children: [{_id: 1}]}, function(error, doc) {
+      MyModel.create({ children: [{ _id: 1 }] }, function(error, doc) {
         assert.ifError(error);
         MyModel.findOneAndUpdate(
-          {_id: doc._id, 'children._id': 1},
-          {$set: {'children.$': {_id: 2}}},
-          {new: true},
+          { _id: doc._id, 'children._id': 1 },
+          { $set: { 'children.$': { _id: 2 } } },
+          { new: true },
           function(error, doc) {
             assert.ifError(error);
             assert.equal(doc.children[0]._id, 2);
@@ -1528,13 +1528,13 @@ describe('model: update:', function() {
     });
 
     it('mixed type casting (gh-3305)', function(done) {
-      const Schema = mongoose.Schema({}, {strict: false});
+      const Schema = mongoose.Schema({}, { strict: false });
       const Model = db.model('Test', Schema);
 
       Model.create({}, function(error, m) {
         assert.ifError(error);
         Model.
-          update({_id: m._id}, {$push: {myArr: {key: 'Value'}}}).
+          update({ _id: m._id }, { $push: { myArr: { key: 'Value' } } }).
           exec(function(error, res) {
             assert.ifError(error);
             assert.equal(res.n, 1);
@@ -1566,14 +1566,14 @@ describe('model: update:', function() {
     });
 
     it('mixed nested type casting (gh-3337)', function(done) {
-      const Schema = mongoose.Schema({attributes: {}}, {strict: true});
+      const Schema = mongoose.Schema({ attributes: {} }, { strict: true });
       const Model = db.model('Test', Schema);
 
       Model.create({}, function(error, m) {
         assert.ifError(error);
-        const update = {$push: {'attributes.scores.bar': {a: 1}}};
+        const update = { $push: { 'attributes.scores.bar': { a: 1 } } };
         Model.
-          update({_id: m._id}, update).
+          update({ _id: m._id }, update).
           exec(function(error, res) {
             assert.ifError(error);
             assert.equal(res.n, 1);
@@ -1651,23 +1651,23 @@ describe('model: update:', function() {
     });
 
     it('works with buffers (gh-3496)', function(done) {
-      const Schema = mongoose.Schema({myBufferField: Buffer});
+      const Schema = mongoose.Schema({ myBufferField: Buffer });
       const Model = db.model('Test', Schema);
 
-      Model.update({}, {myBufferField: Buffer.alloc(1)}, function(error) {
+      Model.update({}, { myBufferField: Buffer.alloc(1) }, function(error) {
         assert.ifError(error);
         done();
       });
     });
 
     it('.update(doc) (gh-3221)', function() {
-      const Schema = mongoose.Schema({name: String});
+      const Schema = mongoose.Schema({ name: String });
       const Model = db.model('Test', Schema);
 
-      let query = Model.update({name: 'Val'});
+      let query = Model.update({ name: 'Val' });
       assert.equal(query.getUpdate().name, 'Val');
 
-      query = Model.find().update({name: 'Val'});
+      query = Model.find().update({ name: 'Val' });
       assert.equal(query.getUpdate().name, 'Val');
 
       return query.setOptions({ upsert: true }).
@@ -1701,10 +1701,10 @@ describe('model: update:', function() {
     });
 
     it('middleware update with exec (gh-3549)', function(done) {
-      const Schema = mongoose.Schema({name: String});
+      const Schema = mongoose.Schema({ name: String });
 
       Schema.pre('update', function(next) {
-        this.update({name: 'Val'});
+        this.update({ name: 'Val' });
         next();
       });
 
@@ -1712,9 +1712,9 @@ describe('model: update:', function() {
 
       Model.create({}, function(error, doc) {
         assert.ifError(error);
-        Model.update({_id: doc._id}, {name: 'test'}).exec(function(error) {
+        Model.update({ _id: doc._id }, { name: 'test' }).exec(function(error) {
           assert.ifError(error);
-          Model.findOne({_id: doc._id}, function(error, doc) {
+          Model.findOne({ _id: doc._id }, function(error, doc) {
             assert.ifError(error);
             assert.equal(doc.name, 'Val');
             done();
@@ -1741,12 +1741,12 @@ describe('model: update:', function() {
       M.create(doc, function(err) {
         assert.ifError(err);
 
-        const update = {$push: {followers: 200}};
-        const opts = {overwrite: true, new: true, safe: true, upsert: false, multi: false};
+        const update = { $push: { followers: 200 } };
+        const opts = { overwrite: true, new: true, safe: true, upsert: false, multi: false };
 
-        M.update({topicId: doc.topicId}, update, opts, function(err) {
+        M.update({ topicId: doc.topicId }, update, opts, function(err) {
           assert.ifError(err);
-          M.findOne({topicId: doc.topicId}, function(error, doc) {
+          M.findOne({ topicId: doc.topicId }, function(error, doc) {
             assert.ifError(error);
             assert.equal(doc.name, 'name');
             assert.deepEqual(doc.followers.toObject(), [500, 200]);
@@ -2202,7 +2202,7 @@ describe('model: update:', function() {
 
     it('single nested schema with geo (gh-4465)', function(done) {
       const addressSchema = new Schema({
-        geo: {type: [Number], index: '2dsphere'}
+        geo: { type: [Number], index: '2dsphere' }
       }, { _id: false });
       const containerSchema = new Schema({ address: addressSchema });
       const Container = db.model('Test', containerSchema);
@@ -2222,14 +2222,14 @@ describe('model: update:', function() {
         return true;
       });
 
-      let B = new Schema({a: [A]});
+      let B = new Schema({ a: [A] });
 
       B = db.model('Test', B);
 
       B.findOneAndUpdate(
-        {foo: 'bar'},
-        {$set: {a: [{str: {somekey: 'someval'}}]}},
-        {runValidators: true},
+        { foo: 'bar' },
+        { $set: { a: [{ str: { somekey: 'someval' } }] } },
+        { runValidators: true },
         function(err) {
           assert.ifError(err);
           assert.equal(validateCalls, 1);
@@ -2261,7 +2261,7 @@ describe('model: update:', function() {
 
       User.create({ profiles: [] }, function(error, user) {
         assert.ifError(error);
-        User.update({ _id: user._id }, {$set: {'profiles.0.rules': {}}}).
+        User.update({ _id: user._id }, { $set: { 'profiles.0.rules': {} } }).
           exec(function(error) {
             assert.ifError(error);
             User.findOne({ _id: user._id }).lean().exec(function(error, doc) {
@@ -2441,7 +2441,7 @@ describe('model: update:', function() {
       }, { strict: true });
       const Test = db.model('Test', schema);
 
-      const doc = new Test({ name: 'Test', arr: [null, {name: 'abc'}] });
+      const doc = new Test({ name: 'Test', arr: [null, { name: 'abc' }] });
 
       return doc.save().
         then(function(doc) {
@@ -2460,7 +2460,7 @@ describe('model: update:', function() {
 
     it('$set array (gh-5403)', function(done) {
       const Schema = new mongoose.Schema({
-        colors: [{type: String}]
+        colors: [{ type: String }]
       });
 
       const Model = db.model('Test', Schema);
@@ -2933,7 +2933,7 @@ describe('model: update:', function() {
       Test.create(doc, function(error, doc) {
         assert.ifError(error);
         doc.foo = 'baz';
-        Test.update({_id: doc._id}, doc, {upsert: true}, function(error) {
+        Test.update({ _id: doc._id }, doc, { upsert: true }, function(error) {
           assert.ifError(error);
           Test.findOne({ _id: doc._id }, function(error, doc) {
             assert.ifError(error);
diff --git a/test/object.create.null.test.js b/test/object.create.null.test.js
index 27447e033db..3b3bb1c9f3d 100644
--- a/test/object.create.null.test.js
+++ b/test/object.create.null.test.js
@@ -22,9 +22,9 @@ describe('is compatible with object created using Object.create(null) (gh-1484)'
       a: String,
       b: {
         c: Number,
-        d: [{e: String}]
+        d: [{ e: String }]
       },
-      f: {g: Date},
+      f: { g: Date },
       h: {}
     });
   });
@@ -134,7 +134,7 @@ describe('is compatible with object created using Object.create(null) (gh-1484)'
       let o = Object.create(null);
       o = {};
       o.name = String;
-      const x = {type: [o]};
+      const x = { type: [o] };
       s.path('works', x);
     });
 
diff --git a/test/plugin.idGetter.test.js b/test/plugin.idGetter.test.js
index c68497d7a8f..cb13a10c2da 100644
--- a/test/plugin.idGetter.test.js
+++ b/test/plugin.idGetter.test.js
@@ -36,7 +36,7 @@ describe('id virtual getter', function() {
   });
 
   it('should be turned off when `id` option is set to false', function(done) {
-    const schema = new Schema({}, {id: false});
+    const schema = new Schema({}, { id: false });
 
     const S = db.model('NoIdGetter', schema);
     S.create({}, function(err, s) {
@@ -55,7 +55,7 @@ describe('id virtual getter', function() {
     });
 
     const S = db.model('SchemaHasId', schema);
-    S.create({ id: 'test'}, function(err, s) {
+    S.create({ id: 'test' }, function(err, s) {
       assert.ifError(err);
 
       // Comparing with expected value
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index 3b1f60bb803..89f46d1d11e 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -28,7 +28,7 @@ describe('query middleware', function() {
         if (error) {
           return done(error);
         }
-        Publisher.create({name: 'Wiley'}, function(error, publisher) {
+        Publisher.create({ name: 'Wiley' }, function(error, publisher) {
           if (error) {
             return done(error);
           }
@@ -52,7 +52,7 @@ describe('query middleware', function() {
     schema = new Schema({
       title: String,
       author: String,
-      publisher: {type: Schema.ObjectId, ref: 'gh-2138-1'},
+      publisher: { type: Schema.ObjectId, ref: 'gh-2138-1' },
       options: String
     });
 
@@ -80,7 +80,7 @@ describe('query middleware', function() {
 
     initializeData(function(error) {
       assert.ifError(error);
-      Author.find({x: 1}, function(error) {
+      Author.find({ x: 1 }, function(error) {
         assert.ifError(error);
         assert.equal(count, 1);
         done();
@@ -100,7 +100,7 @@ describe('query middleware', function() {
 
     initializeData(function(error) {
       assert.ifError(error);
-      Author.find({title: 'Professional AngularJS'}, function(error, docs) {
+      Author.find({ title: 'Professional AngularJS' }, function(error, docs) {
         assert.ifError(error);
         assert.equal(postCount, 1);
         assert.equal(docs.length, 1);
@@ -125,7 +125,7 @@ describe('query middleware', function() {
     });
 
     initializeData(function() {
-      Author.find({title: 'Professional AngularJS'}).exec(function(error, docs) {
+      Author.find({ title: 'Professional AngularJS' }).exec(function(error, docs) {
         assert.ifError(error);
         assert.equal(count, 1);
         assert.equal(postCount, 1);
@@ -150,7 +150,7 @@ describe('query middleware', function() {
     });
 
     initializeData(function() {
-      Author.findOne({title: 'Professional AngularJS'}).exec(function(error, doc) {
+      Author.findOne({ title: 'Professional AngularJS' }).exec(function(error, doc) {
         assert.ifError(error);
         assert.equal(count, 1);
         assert.equal(postCount, 1);
@@ -174,7 +174,7 @@ describe('query middleware', function() {
     });
 
     initializeData(function() {
-      Author.findOne({title: 'Professional AngularJS'}).exec(function(error, doc) {
+      Author.findOne({ title: 'Professional AngularJS' }).exec(function(error, doc) {
         assert.ifError(error);
         assert.equal(count, 1);
         assert.equal(postCount, 1);
@@ -182,7 +182,7 @@ describe('query middleware', function() {
 
         count = 0;
         postCount = 0;
-        Author.find({title: 'Professional AngularJS'}, function(error, docs) {
+        Author.find({ title: 'Professional AngularJS' }, function(error, docs) {
           assert.ifError(error);
           assert.equal(count, 1);
           assert.equal(postCount, 1);
@@ -206,7 +206,7 @@ describe('query middleware', function() {
     });
 
     initializeData(function() {
-      Author.findOne({title: 'Professional AngularJS'}).exec(function(error, doc) {
+      Author.findOne({ title: 'Professional AngularJS' }).exec(function(error, doc) {
         assert.ifError(error);
         assert.equal(doc.author, 'Val');
         assert.equal(doc.publisher.name, 'Wiley');
@@ -223,7 +223,7 @@ describe('query middleware', function() {
     });
 
     initializeData(function() {
-      Author.findOne({title: 'Professional AngularJS'}).exec(function(error, doc) {
+      Author.findOne({ title: 'Professional AngularJS' }).exec(function(error, doc) {
         assert.ifError(error);
         assert.equal(doc.author, 'Val');
         assert.equal(doc.publisher.name, 'Wiley');
@@ -501,7 +501,7 @@ describe('query middleware', function() {
   });
 
   it('error handlers with findOneAndUpdate and passRawResult (gh-4836)', function(done) {
-    const schema = new Schema({name: {type: String}});
+    const schema = new Schema({ name: { type: String } });
 
     let called = false;
     const errorHandler = function(err, res, next) {
@@ -514,7 +514,7 @@ describe('query middleware', function() {
     const Person = db.model('Person', schema);
 
     Person.
-      findOneAndUpdate({name: 'name'}, {}, {upsert: true, passRawResult: true}).
+      findOneAndUpdate({ name: 'name' }, {}, { upsert: true, passRawResult: true }).
       exec(function(error) {
         assert.ifError(error);
         assert.ok(!called);
@@ -523,7 +523,7 @@ describe('query middleware', function() {
   });
 
   it('error handlers with findOneAndUpdate error and passRawResult (gh-4836)', function(done) {
-    const schema = new Schema({name: {type: String}});
+    const schema = new Schema({ name: { type: String } });
 
     let called = false;
     const errorHandler = function(err, res, next) {
@@ -536,7 +536,7 @@ describe('query middleware', function() {
     const Person = db.model('Person', schema);
 
     Person.
-      findOneAndUpdate({}, {_id: 'test'}, {upsert: true, passRawResult: true}).
+      findOneAndUpdate({}, { _id: 'test' }, { upsert: true, passRawResult: true }).
       exec(function(error) {
         assert.ok(error);
         assert.ok(called);
diff --git a/test/query.test.js b/test/query.test.js
index e28cb656c8e..66c328c5e16 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -63,15 +63,15 @@ describe('Query', function() {
   describe('select', function() {
     it('(object)', function(done) {
       const query = new Query({});
-      query.select({a: 1, b: 1, c: 0});
-      assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
+      query.select({ a: 1, b: 1, c: 0 });
+      assert.deepEqual(query._fields, { a: 1, b: 1, c: 0 });
       done();
     });
 
     it('(string)', function(done) {
       const query = new Query({});
       query.select(' a  b -c ');
-      assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
+      assert.deepEqual(query._fields, { a: 1, b: 1, c: 0 });
       done();
     });
 
@@ -86,13 +86,13 @@ describe('Query', function() {
     it('should not overwrite fields set in prior calls', function(done) {
       const query = new Query({});
       query.select('a');
-      assert.deepEqual(query._fields, {a: 1});
+      assert.deepEqual(query._fields, { a: 1 });
       query.select('b');
-      assert.deepEqual(query._fields, {a: 1, b: 1});
-      query.select({c: 0});
-      assert.deepEqual(query._fields, {a: 1, b: 1, c: 0});
+      assert.deepEqual(query._fields, { a: 1, b: 1 });
+      query.select({ c: 0 });
+      assert.deepEqual(query._fields, { a: 1, b: 1, c: 0 });
       query.select('-d');
-      assert.deepEqual(query._fields, {a: 1, b: 1, c: 0, d: 0});
+      assert.deepEqual(query._fields, { a: 1, b: 1, c: 0, d: 0 });
       done();
     });
   });
@@ -116,10 +116,10 @@ describe('Query', function() {
     it('works', function(done) {
       const query = new Query({});
       query.where('name', 'guillermo');
-      assert.deepEqual(query._conditions, {name: 'guillermo'});
+      assert.deepEqual(query._conditions, { name: 'guillermo' });
       query.where('a');
       query.equals('b');
-      assert.deepEqual(query._conditions, {name: 'guillermo', a: 'b'});
+      assert.deepEqual(query._conditions, { name: 'guillermo', a: 'b' });
       done();
     });
     it('throws if non-string or non-object path is passed', function(done) {
@@ -145,7 +145,7 @@ describe('Query', function() {
     it('works', function(done) {
       const query = new Query({});
       query.where('name').equals('guillermo');
-      assert.deepEqual(query._conditions, {name: 'guillermo'});
+      assert.deepEqual(query._conditions, { name: 'guillermo' });
       done();
     });
   });
@@ -154,13 +154,13 @@ describe('Query', function() {
     it('with 2 args', function(done) {
       const query = new Query({});
       query.gte('age', 18);
-      assert.deepEqual(query._conditions, {age: {$gte: 18}});
+      assert.deepEqual(query._conditions, { age: { $gte: 18 } });
       done();
     });
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').gte(18);
-      assert.deepEqual(query._conditions, {age: {$gte: 18}});
+      assert.deepEqual(query._conditions, { age: { $gte: 18 } });
       done();
     });
   });
@@ -169,13 +169,13 @@ describe('Query', function() {
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').gt(17);
-      assert.deepEqual(query._conditions, {age: {$gt: 17}});
+      assert.deepEqual(query._conditions, { age: { $gt: 17 } });
       done();
     });
     it('with 2 args', function(done) {
       const query = new Query({});
       query.gt('age', 17);
-      assert.deepEqual(query._conditions, {age: {$gt: 17}});
+      assert.deepEqual(query._conditions, { age: { $gt: 17 } });
       done();
     });
   });
@@ -184,13 +184,13 @@ describe('Query', function() {
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').lte(65);
-      assert.deepEqual(query._conditions, {age: {$lte: 65}});
+      assert.deepEqual(query._conditions, { age: { $lte: 65 } });
       done();
     });
     it('with 2 args', function(done) {
       const query = new Query({});
       query.lte('age', 65);
-      assert.deepEqual(query._conditions, {age: {$lte: 65}});
+      assert.deepEqual(query._conditions, { age: { $lte: 65 } });
       done();
     });
   });
@@ -199,13 +199,13 @@ describe('Query', function() {
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').lt(66);
-      assert.deepEqual(query._conditions, {age: {$lt: 66}});
+      assert.deepEqual(query._conditions, { age: { $lt: 66 } });
       done();
     });
     it('with 2 args', function(done) {
       const query = new Query({});
       query.lt('age', 66);
-      assert.deepEqual(query._conditions, {age: {$lt: 66}});
+      assert.deepEqual(query._conditions, { age: { $lt: 66 } });
       done();
     });
   });
@@ -215,7 +215,7 @@ describe('Query', function() {
       it('works', function(done) {
         const query = new Query({});
         query.where('age').lt(66).gt(17);
-        assert.deepEqual(query._conditions, {age: {$lt: 66, $gt: 17}});
+        assert.deepEqual(query._conditions, { age: { $lt: 66, $gt: 17 } });
         done();
       });
     });
@@ -227,7 +227,7 @@ describe('Query', function() {
       query
         .where('age').lt(66)
         .where('height').gt(5);
-      assert.deepEqual(query._conditions, {age: {$lt: 66}, height: {$gt: 5}});
+      assert.deepEqual(query._conditions, { age: { $lt: 66 }, height: { $gt: 5 } });
       done();
     });
   });
@@ -236,13 +236,13 @@ describe('Query', function() {
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').ne(21);
-      assert.deepEqual(query._conditions, {age: {$ne: 21}});
+      assert.deepEqual(query._conditions, { age: { $ne: 21 } });
       done();
     });
     it('with 2 args', function(done) {
       const query = new Query({});
       query.ne('age', 21);
-      assert.deepEqual(query._conditions, {age: {$ne: 21}});
+      assert.deepEqual(query._conditions, { age: { $ne: 21 } });
       done();
     });
   });
@@ -251,25 +251,25 @@ describe('Query', function() {
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').in([21, 25, 30]);
-      assert.deepEqual(query._conditions, {age: {$in: [21, 25, 30]}});
+      assert.deepEqual(query._conditions, { age: { $in: [21, 25, 30] } });
       done();
     });
     it('with 2 args', function(done) {
       const query = new Query({});
       query.in('age', [21, 25, 30]);
-      assert.deepEqual(query._conditions, {age: {$in: [21, 25, 30]}});
+      assert.deepEqual(query._conditions, { age: { $in: [21, 25, 30] } });
       done();
     });
     it('where a non-array value no via where', function(done) {
       const query = new Query({});
       query.in('age', 21);
-      assert.deepEqual(query._conditions, {age: {$in: 21}});
+      assert.deepEqual(query._conditions, { age: { $in: 21 } });
       done();
     });
     it('where a non-array value via where', function(done) {
       const query = new Query({});
       query.where('age').in(21);
-      assert.deepEqual(query._conditions, {age: {$in: 21}});
+      assert.deepEqual(query._conditions, { age: { $in: 21 } });
       done();
     });
   });
@@ -278,25 +278,25 @@ describe('Query', function() {
     it('with 1 arg', function(done) {
       const query = new Query({});
       query.where('age').nin([21, 25, 30]);
-      assert.deepEqual(query._conditions, {age: {$nin: [21, 25, 30]}});
+      assert.deepEqual(query._conditions, { age: { $nin: [21, 25, 30] } });
       done();
     });
     it('with 2 args', function(done) {
       const query = new Query({});
       query.nin('age', [21, 25, 30]);
-      assert.deepEqual(query._conditions, {age: {$nin: [21, 25, 30]}});
+      assert.deepEqual(query._conditions, { age: { $nin: [21, 25, 30] } });
       done();
     });
     it('with a non-array value not via where', function(done) {
       const query = new Query({});
       query.nin('age', 21);
-      assert.deepEqual(query._conditions, {age: {$nin: 21}});
+      assert.deepEqual(query._conditions, { age: { $nin: 21 } });
       done();
     });
     it('with a non-array value via where', function(done) {
       const query = new Query({});
       query.where('age').nin(21);
-      assert.deepEqual(query._conditions, {age: {$nin: 21}});
+      assert.deepEqual(query._conditions, { age: { $nin: 21 } });
       done();
     });
   });
@@ -305,25 +305,25 @@ describe('Query', function() {
     it('not via where, where [a, b] param', function(done) {
       const query = new Query({});
       query.mod('age', [5, 2]);
-      assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
+      assert.deepEqual(query._conditions, { age: { $mod: [5, 2] } });
       done();
     });
     it('not via where, where a and b params', function(done) {
       const query = new Query({});
       query.mod('age', 5, 2);
-      assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
+      assert.deepEqual(query._conditions, { age: { $mod: [5, 2] } });
       done();
     });
     it('via where, where [a, b] param', function(done) {
       const query = new Query({});
       query.where('age').mod([5, 2]);
-      assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
+      assert.deepEqual(query._conditions, { age: { $mod: [5, 2] } });
       done();
     });
     it('via where, where a and b params', function(done) {
       const query = new Query({});
       query.where('age').mod(5, 2);
-      assert.deepEqual(query._conditions, {age: {$mod: [5, 2]}});
+      assert.deepEqual(query._conditions, { age: { $mod: [5, 2] } });
       done();
     });
   });
@@ -331,38 +331,38 @@ describe('Query', function() {
   describe('near', function() {
     it('via where, where { center :[lat, long]} param', function(done) {
       const query = new Query({});
-      query.where('checkin').near({center: [40, -72]});
-      assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
+      query.where('checkin').near({ center: [40, -72] });
+      assert.deepEqual(query._conditions, { checkin: { $near: [40, -72] } });
       done();
     });
     it('via where, where [lat, long] param', function(done) {
       const query = new Query({});
       query.where('checkin').near([40, -72]);
-      assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $near: [40, -72] } });
       done();
     });
     it('via where, where lat and long params', function(done) {
       const query = new Query({});
       query.where('checkin').near(40, -72);
-      assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $near: [40, -72] } });
       done();
     });
     it('not via where, where [lat, long] param', function(done) {
       const query = new Query({});
       query.near('checkin', [40, -72]);
-      assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $near: [40, -72] } });
       done();
     });
     it('not via where, where lat and long params', function(done) {
       const query = new Query({});
       query.near('checkin', 40, -72);
-      assert.deepEqual(query._conditions, {checkin: {$near: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $near: [40, -72] } });
       done();
     });
     it('via where, where GeoJSON param', function(done) {
       const query = new Query({});
-      query.where('numbers').near({center: {type: 'Point', coordinates: [40, -72]}});
-      assert.deepEqual(query._conditions, {numbers: {$near: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
+      query.where('numbers').near({ center: { type: 'Point', coordinates: [40, -72] } });
+      assert.deepEqual(query._conditions, { numbers: { $near: { $geometry: { type: 'Point', coordinates: [40, -72] } } } });
       assert.doesNotThrow(function() {
         query.cast(db.model('Product', productSchema));
       });
@@ -370,8 +370,8 @@ describe('Query', function() {
     });
     it('with path, where GeoJSON param', function(done) {
       const query = new Query({});
-      query.near('loc', {center: {type: 'Point', coordinates: [40, -72]}});
-      assert.deepEqual(query._conditions, {loc: {$near: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
+      query.near('loc', { center: { type: 'Point', coordinates: [40, -72] } });
+      assert.deepEqual(query._conditions, { loc: { $near: { $geometry: { type: 'Point', coordinates: [40, -72] } } } });
       done();
     });
   });
@@ -380,39 +380,39 @@ describe('Query', function() {
     it('via where, where [lat, long] param', function(done) {
       const query = new Query({});
       query.where('checkin').nearSphere([40, -72]);
-      assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $nearSphere: [40, -72] } });
       done();
     });
     it('via where, where lat and long params', function(done) {
       const query = new Query({});
       query.where('checkin').nearSphere(40, -72);
-      assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $nearSphere: [40, -72] } });
       done();
     });
     it('not via where, where [lat, long] param', function(done) {
       const query = new Query({});
       query.nearSphere('checkin', [40, -72]);
-      assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $nearSphere: [40, -72] } });
       done();
     });
     it('not via where, where lat and long params', function(done) {
       const query = new Query({});
       query.nearSphere('checkin', 40, -72);
-      assert.deepEqual(query._conditions, {checkin: {$nearSphere: [40, -72]}});
+      assert.deepEqual(query._conditions, { checkin: { $nearSphere: [40, -72] } });
       done();
     });
 
     it('via where, with object', function(done) {
       const query = new Query({});
-      query.where('checkin').nearSphere({center: [20, 23], maxDistance: 2});
-      assert.deepEqual(query._conditions, {checkin: {$nearSphere: [20, 23], $maxDistance: 2}});
+      query.where('checkin').nearSphere({ center: [20, 23], maxDistance: 2 });
+      assert.deepEqual(query._conditions, { checkin: { $nearSphere: [20, 23], $maxDistance: 2 } });
       done();
     });
 
     it('via where, where GeoJSON param', function(done) {
       const query = new Query({});
-      query.where('numbers').nearSphere({center: {type: 'Point', coordinates: [40, -72]}});
-      assert.deepEqual(query._conditions, {numbers: {$nearSphere: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
+      query.where('numbers').nearSphere({ center: { type: 'Point', coordinates: [40, -72] } });
+      assert.deepEqual(query._conditions, { numbers: { $nearSphere: { $geometry: { type: 'Point', coordinates: [40, -72] } } } });
       assert.doesNotThrow(function() {
         query.cast(db.model('Product', productSchema));
       });
@@ -421,8 +421,8 @@ describe('Query', function() {
 
     it('with path, with GeoJSON', function(done) {
       const query = new Query({});
-      query.nearSphere('numbers', {center: {type: 'Point', coordinates: [40, -72]}});
-      assert.deepEqual(query._conditions, {numbers: {$nearSphere: {$geometry: {type: 'Point', coordinates: [40, -72]}}}});
+      query.nearSphere('numbers', { center: { type: 'Point', coordinates: [40, -72] } });
+      assert.deepEqual(query._conditions, { numbers: { $nearSphere: { $geometry: { type: 'Point', coordinates: [40, -72] } } } });
       assert.doesNotThrow(function() {
         query.cast(db.model('Product', productSchema));
       });
@@ -434,7 +434,7 @@ describe('Query', function() {
     it('via where', function(done) {
       const query = new Query({});
       query.where('checkin').near([40, -72]).maxDistance(1);
-      assert.deepEqual(query._conditions, {checkin: {$near: [40, -72], $maxDistance: 1}});
+      assert.deepEqual(query._conditions, { checkin: { $near: [40, -72], $maxDistance: 1 } });
       done();
     });
   });
@@ -443,8 +443,8 @@ describe('Query', function() {
     describe('box', function() {
       it('via where', function(done) {
         const query = new Query({});
-        query.where('gps').within().box({ll: [5, 25], ur: [10, 30]});
-        const match = {gps: {$within: {$box: [[5, 25], [10, 30]]}}};
+        query.where('gps').within().box({ ll: [5, 25], ur: [10, 30] });
+        const match = { gps: { $within: { $box: [[5, 25], [10, 30]] } } };
         if (Query.use$geoWithin) {
           match.gps.$geoWithin = match.gps.$within;
           delete match.gps.$within;
@@ -455,7 +455,7 @@ describe('Query', function() {
       it('via where, no object', function(done) {
         const query = new Query({});
         query.where('gps').within().box([5, 25], [10, 30]);
-        const match = {gps: {$within: {$box: [[5, 25], [10, 30]]}}};
+        const match = { gps: { $within: { $box: [[5, 25], [10, 30]] } } };
         if (Query.use$geoWithin) {
           match.gps.$geoWithin = match.gps.$within;
           delete match.gps.$within;
@@ -468,8 +468,8 @@ describe('Query', function() {
     describe('center', function() {
       it('via where', function(done) {
         const query = new Query({});
-        query.where('gps').within().center({center: [5, 25], radius: 5});
-        const match = {gps: {$within: {$center: [[5, 25], 5]}}};
+        query.where('gps').within().center({ center: [5, 25], radius: 5 });
+        const match = { gps: { $within: { $center: [[5, 25], 5] } } };
         if (Query.use$geoWithin) {
           match.gps.$geoWithin = match.gps.$within;
           delete match.gps.$within;
@@ -482,8 +482,8 @@ describe('Query', function() {
     describe('centerSphere', function() {
       it('via where', function(done) {
         const query = new Query({});
-        query.where('gps').within().centerSphere({center: [5, 25], radius: 5});
-        const match = {gps: {$within: {$centerSphere: [[5, 25], 5]}}};
+        query.where('gps').within().centerSphere({ center: [5, 25], radius: 5 });
+        const match = { gps: { $within: { $centerSphere: [[5, 25], 5] } } };
         if (Query.use$geoWithin) {
           match.gps.$geoWithin = match.gps.$within;
           delete match.gps.$within;
@@ -496,8 +496,8 @@ describe('Query', function() {
     describe('polygon', function() {
       it('via where', function(done) {
         const query = new Query({});
-        query.where('gps').within().polygon({a: {x: 10, y: 20}, b: {x: 15, y: 25}, c: {x: 20, y: 20}});
-        const match = {gps: {$within: {$polygon: [{a: {x: 10, y: 20}, b: {x: 15, y: 25}, c: {x: 20, y: 20}}]}}};
+        query.where('gps').within().polygon({ a: { x: 10, y: 20 }, b: { x: 15, y: 25 }, c: { x: 20, y: 20 } });
+        const match = { gps: { $within: { $polygon: [{ a: { x: 10, y: 20 }, b: { x: 15, y: 25 }, c: { x: 20, y: 20 } }] } } };
         if (Query.use$geoWithin) {
           match.gps.$geoWithin = match.gps.$within;
           delete match.gps.$within;
@@ -512,26 +512,26 @@ describe('Query', function() {
     it('0 args via where', function(done) {
       const query = new Query({});
       query.where('username').exists();
-      assert.deepEqual(query._conditions, {username: {$exists: true}});
+      assert.deepEqual(query._conditions, { username: { $exists: true } });
       done();
     });
     it('1 arg via where', function(done) {
       const query = new Query({});
       query.where('username').exists(false);
-      assert.deepEqual(query._conditions, {username: {$exists: false}});
+      assert.deepEqual(query._conditions, { username: { $exists: false } });
       done();
     });
     it('where 1 argument not via where', function(done) {
       const query = new Query({});
       query.exists('username');
-      assert.deepEqual(query._conditions, {username: {$exists: true}});
+      assert.deepEqual(query._conditions, { username: { $exists: true } });
       done();
     });
 
     it('where 2 args not via where', function(done) {
       const query = new Query({});
       query.exists('username', false);
-      assert.deepEqual(query._conditions, {username: {$exists: false}});
+      assert.deepEqual(query._conditions, { username: { $exists: false } });
       done();
     });
   });
@@ -540,13 +540,13 @@ describe('Query', function() {
     it('via where', function(done) {
       const query = new Query({});
       query.where('pets').all(['dog', 'cat', 'ferret']);
-      assert.deepEqual(query._conditions, {pets: {$all: ['dog', 'cat', 'ferret']}});
+      assert.deepEqual(query._conditions, { pets: { $all: ['dog', 'cat', 'ferret'] } });
       done();
     });
     it('not via where', function(done) {
       const query = new Query({});
       query.all('pets', ['dog', 'cat', 'ferret']);
-      assert.deepEqual(query._conditions, {pets: {$all: ['dog', 'cat', 'ferret']}});
+      assert.deepEqual(query._conditions, { pets: { $all: ['dog', 'cat', 'ferret'] } });
       done();
     });
   });
@@ -554,8 +554,8 @@ describe('Query', function() {
   describe('find', function() {
     it('strict array equivalence condition v', function(done) {
       const query = new Query({});
-      query.find({pets: ['dog', 'cat', 'ferret']});
-      assert.deepEqual(query._conditions, {pets: ['dog', 'cat', 'ferret']});
+      query.find({ pets: ['dog', 'cat', 'ferret'] });
+      assert.deepEqual(query._conditions, { pets: ['dog', 'cat', 'ferret'] });
       done();
     });
     it('with no args', function(done) {
@@ -575,10 +575,10 @@ describe('Query', function() {
     it('works with overwriting previous object args (1176)', function(done) {
       const q = new Query({});
       assert.doesNotThrow(function() {
-        q.find({age: {$lt: 30}});
-        q.find({age: 20}); // overwrite
+        q.find({ age: { $lt: 30 } });
+        q.find({ age: 20 }); // overwrite
       });
-      assert.deepEqual({age: 20}, q._conditions);
+      assert.deepEqual({ age: 20 }, q._conditions);
       done();
     });
   });
@@ -587,13 +587,13 @@ describe('Query', function() {
     it('via where', function(done) {
       const query = new Query({});
       query.where('collection').size(5);
-      assert.deepEqual(query._conditions, {collection: {$size: 5}});
+      assert.deepEqual(query._conditions, { collection: { $size: 5 } });
       done();
     });
     it('not via where', function(done) {
       const query = new Query({});
       query.size('collection', 5);
-      assert.deepEqual(query._conditions, {collection: {$size: 5}});
+      assert.deepEqual(query._conditions, { collection: { $size: 5 } });
       done();
     });
   });
@@ -602,73 +602,73 @@ describe('Query', function() {
     it('where and positive limit param', function(done) {
       const query = new Query({});
       query.where('collection').slice(5);
-      assert.deepEqual(query._fields, {collection: {$slice: 5}});
+      assert.deepEqual(query._fields, { collection: { $slice: 5 } });
       done();
     });
     it('where just negative limit param', function(done) {
       const query = new Query({});
       query.where('collection').slice(-5);
-      assert.deepEqual(query._fields, {collection: {$slice: -5}});
+      assert.deepEqual(query._fields, { collection: { $slice: -5 } });
       done();
     });
     it('where [skip, limit] param', function(done) {
       const query = new Query({});
       query.where('collection').slice([14, 10]); // Return the 15th through 25th
-      assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
+      assert.deepEqual(query._fields, { collection: { $slice: [14, 10] } });
       done();
     });
     it('where skip and limit params', function(done) {
       const query = new Query({});
       query.where('collection').slice(14, 10); // Return the 15th through 25th
-      assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
+      assert.deepEqual(query._fields, { collection: { $slice: [14, 10] } });
       done();
     });
     it('where just positive limit param', function(done) {
       const query = new Query({});
       query.where('collection').slice(5);
-      assert.deepEqual(query._fields, {collection: {$slice: 5}});
+      assert.deepEqual(query._fields, { collection: { $slice: 5 } });
       done();
     });
     it('where just negative limit param', function(done) {
       const query = new Query({});
       query.where('collection').slice(-5);
-      assert.deepEqual(query._fields, {collection: {$slice: -5}});
+      assert.deepEqual(query._fields, { collection: { $slice: -5 } });
       done();
     });
     it('where the [skip, limit] param', function(done) {
       const query = new Query({});
       query.where('collection').slice([14, 10]); // Return the 15th through 25th
-      assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
+      assert.deepEqual(query._fields, { collection: { $slice: [14, 10] } });
       done();
     });
     it('where the skip and limit params', function(done) {
       const query = new Query({});
       query.where('collection').slice(14, 10); // Return the 15th through 25th
-      assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
+      assert.deepEqual(query._fields, { collection: { $slice: [14, 10] } });
       done();
     });
     it('not via where, with just positive limit param', function(done) {
       const query = new Query({});
       query.slice('collection', 5);
-      assert.deepEqual(query._fields, {collection: {$slice: 5}});
+      assert.deepEqual(query._fields, { collection: { $slice: 5 } });
       done();
     });
     it('not via where, where just negative limit param', function(done) {
       const query = new Query({});
       query.slice('collection', -5);
-      assert.deepEqual(query._fields, {collection: {$slice: -5}});
+      assert.deepEqual(query._fields, { collection: { $slice: -5 } });
       done();
     });
     it('not via where, where [skip, limit] param', function(done) {
       const query = new Query({});
       query.slice('collection', [14, 10]); // Return the 15th through 25th
-      assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
+      assert.deepEqual(query._fields, { collection: { $slice: [14, 10] } });
       done();
     });
     it('not via where, where skip and limit params', function(done) {
       const query = new Query({});
       query.slice('collection', 14, 10); // Return the 15th through 25th
-      assert.deepEqual(query._fields, {collection: {$slice: [14, 10]}});
+      assert.deepEqual(query._fields, { collection: { $slice: [14, 10] } });
       done();
     });
   });
@@ -677,8 +677,8 @@ describe('Query', function() {
     describe('not via where', function() {
       it('works', function(done) {
         const query = new Query({});
-        query.elemMatch('comments', {author: 'bnoguchi', votes: {$gte: 5}});
-        assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
+        query.elemMatch('comments', { author: 'bnoguchi', votes: { $gte: 5 } });
+        assert.deepEqual(query._conditions, { comments: { $elemMatch: { author: 'bnoguchi', votes: { $gte: 5 } } } });
         done();
       });
       it('where block notation', function(done) {
@@ -687,15 +687,15 @@ describe('Query', function() {
           elem.where('author', 'bnoguchi');
           elem.where('votes').gte(5);
         });
-        assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
+        assert.deepEqual(query._conditions, { comments: { $elemMatch: { author: 'bnoguchi', votes: { $gte: 5 } } } });
         done();
       });
     });
     describe('via where', function() {
       it('works', function(done) {
         const query = new Query({});
-        query.where('comments').elemMatch({author: 'bnoguchi', votes: {$gte: 5}});
-        assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
+        query.where('comments').elemMatch({ author: 'bnoguchi', votes: { $gte: 5 } });
+        assert.deepEqual(query._conditions, { comments: { $elemMatch: { author: 'bnoguchi', votes: { $gte: 5 } } } });
         done();
       });
       it('where block notation', function(done) {
@@ -704,7 +704,7 @@ describe('Query', function() {
           elem.where('author', 'bnoguchi');
           elem.where('votes').gte(5);
         });
-        assert.deepEqual(query._conditions, {comments: {$elemMatch: {author: 'bnoguchi', votes: {$gte: 5}}}});
+        assert.deepEqual(query._conditions, { comments: { $elemMatch: { author: 'bnoguchi', votes: { $gte: 5 } } } });
         done();
       });
     });
@@ -719,13 +719,13 @@ describe('Query', function() {
       }
 
       query.$where(filter);
-      assert.deepEqual(query._conditions, {$where: filter});
+      assert.deepEqual(query._conditions, { $where: filter });
       done();
     });
     it('string arg', function(done) {
       const query = new Query({});
       query.$where('this.lastName === this.firstName');
-      assert.deepEqual(query._conditions, {$where: 'this.lastName === this.firstName'});
+      assert.deepEqual(query._conditions, { $where: 'this.lastName === this.firstName' });
       done();
     });
   });
@@ -752,10 +752,10 @@ describe('Query', function() {
     it('works', function(done) {
       let query = new Query({});
       query.sort('a -c b');
-      assert.deepEqual(query.options.sort, {a: 1, c: -1, b: 1});
+      assert.deepEqual(query.options.sort, { a: 1, c: -1, b: 1 });
       query = new Query({});
-      query.sort({a: 1, c: -1, b: 'asc', e: 'descending', f: 'ascending'});
-      assert.deepEqual(query.options.sort, {a: 1, c: -1, b: 1, e: -1, f: 1});
+      query.sort({ a: 1, c: -1, b: 'asc', e: 'descending', f: 'ascending' });
+      assert.deepEqual(query.options.sort, { a: 1, c: -1, b: 1, e: -1, f: 1 });
 
       if (typeof global.Map !== 'undefined') {
         query = new Query({});
@@ -791,12 +791,12 @@ describe('Query', function() {
   describe('or', function() {
     it('works', function(done) {
       const query = new Query;
-      query.find({$or: [{x: 1}, {x: 2}]});
+      query.find({ $or: [{ x: 1 }, { x: 2 }] });
       assert.equal(query._conditions.$or.length, 2);
-      query.or([{y: 'We\'re under attack'}, {z: 47}]);
+      query.or([{ y: 'We\'re under attack' }, { z: 47 }]);
       assert.equal(query._conditions.$or.length, 4);
       assert.equal(query._conditions.$or[3].z, 47);
-      query.or({z: 'phew'});
+      query.or({ z: 'phew' });
       assert.equal(query._conditions.$or.length, 5);
       assert.equal(query._conditions.$or[3].z, 47);
       assert.equal(query._conditions.$or[4].z, 'phew');
@@ -807,12 +807,12 @@ describe('Query', function() {
   describe('and', function() {
     it('works', function(done) {
       const query = new Query;
-      query.find({$and: [{x: 1}, {y: 2}]});
+      query.find({ $and: [{ x: 1 }, { y: 2 }] });
       assert.equal(query._conditions.$and.length, 2);
-      query.and([{z: 'We\'re under attack'}, {w: 47}]);
+      query.and([{ z: 'We\'re under attack' }, { w: 47 }]);
       assert.equal(query._conditions.$and.length, 4);
       assert.equal(query._conditions.$and[3].w, 47);
-      query.and({a: 'phew'});
+      query.and({ a: 'phew' });
       assert.equal(query._conditions.$and.length, 5);
       assert.equal(query._conditions.$and[0].x, 1);
       assert.equal(query._conditions.$and[1].y, 2);
@@ -828,7 +828,7 @@ describe('Query', function() {
       const q = new Query({});
       const o = {
         path: 'yellow.brick',
-        match: {bricks: {$lt: 1000}},
+        match: { bricks: { $lt: 1000 } },
         select: undefined,
         model: undefined,
         options: undefined,
@@ -843,7 +843,7 @@ describe('Query', function() {
       const q = new Query({});
       let o = {
         path: 'yellow.brick',
-        match: {bricks: {$lt: 1000}},
+        match: { bricks: { $lt: 1000 } },
         _docs: {}
       };
       q.populate(Object.assign({}, o));
@@ -880,7 +880,7 @@ describe('Query', function() {
     it('to an array of mixed', function(done) {
       const query = new Query({});
       const Product = db.model('Product', productSchema);
-      const params = {_id: new DocumentObjectId, tags: {$in: [4, 8, 15, 16]}};
+      const params = { _id: new DocumentObjectId, tags: { $in: [4, 8, 15, 16] } };
       query.cast(Product, params);
       assert.deepEqual(params.tags.$in, [4, 8, 15, 16]);
       done();
@@ -931,15 +931,15 @@ describe('Query', function() {
       const Comment = db.model('Comment', commentSchema);
 
       const id = new DocumentObjectId;
-      const castedComment = {_id: id, text: 'hello there'};
+      const castedComment = { _id: id, text: 'hello there' };
       const comment = new Comment(castedComment);
 
       const params = {
-        array: {$ne: 5},
-        ids: {$ne: id},
-        comments: {$ne: comment},
-        strings: {$ne: 'Hi there'},
-        numbers: {$ne: 10000}
+        array: { $ne: 5 },
+        ids: { $ne: id },
+        comments: { $ne: comment },
+        strings: { $ne: 'Hi there' },
+        numbers: { $ne: 10000 }
       };
 
       query.cast(Product, params);
@@ -974,7 +974,7 @@ describe('Query', function() {
       const Product = db.model('Product', productSchema);
 
       const params = {
-        comments: {$ne: null}
+        comments: { $ne: null }
       };
 
       query.cast(Product, params);
@@ -988,7 +988,7 @@ describe('Query', function() {
       const Comment = db.model('Comment', commentSchema);
 
       const id = new DocumentObjectId;
-      const castedComment = {_id: id, text: 'hello there'};
+      const castedComment = { _id: id, text: 'hello there' };
       const comment = new Comment(castedComment);
 
       const params = {
@@ -1030,7 +1030,7 @@ describe('Query', function() {
       const query = new Query({});
       const Product = db.model('Product', productSchema);
       const ids = [String(new DocumentObjectId), String(new DocumentObjectId)];
-      const params = {ids: {$elemMatch: {$in: ids}}};
+      const params = { ids: { $elemMatch: { $in: ids } } };
       query.cast(Product, params);
       assert.ok(params.ids.$elemMatch.$in[0] instanceof DocumentObjectId);
       assert.ok(params.ids.$elemMatch.$in[1] instanceof DocumentObjectId);
@@ -1045,14 +1045,14 @@ describe('Query', function() {
       const Comment = db.model('Comment', commentSchema);
 
       const id = new DocumentObjectId;
-      const castedComment = {_id: id, text: 'hello there'};
+      const castedComment = { _id: id, text: 'hello there' };
       const comment = new Comment(castedComment);
 
       const params = {
-        ids: {$gt: id},
-        comments: {$gt: comment},
-        strings: {$gt: 'Hi there'},
-        numbers: {$gt: 10000}
+        ids: { $gt: id },
+        comments: { $gt: comment },
+        strings: { $gt: 'Hi there' },
+        numbers: { $gt: 10000 }
       };
 
       query.cast(Product, params);
@@ -1136,7 +1136,7 @@ describe('Query', function() {
       const Product = db.model('Product', productSchema);
 
       assert.doesNotThrow(function() {
-        Product.where({numbers: [[[]]]}).deleteMany(function(err) {
+        Product.where({ numbers: [[[]]] }).deleteMany(function(err) {
           assert.ok(err);
           done();
         });
@@ -1146,8 +1146,8 @@ describe('Query', function() {
     it('supports a single conditions arg', function(done) {
       const Product = db.model('Product', productSchema);
 
-      Product.create({strings: ['remove-single-condition']}).then(function() {
-        const q = Product.where().deleteMany({strings: 'remove-single-condition'});
+      Product.create({ strings: ['remove-single-condition'] }).then(function() {
+        const q = Product.where().deleteMany({ strings: 'remove-single-condition' });
         assert.ok(q instanceof mongoose.Query);
         done();
       }, done);
@@ -1157,10 +1157,10 @@ describe('Query', function() {
       const Product = db.model('Product', productSchema);
       const val = 'remove-single-callback';
 
-      Product.create({strings: [val]}).then(function() {
-        Product.where({strings: val}).deleteMany(function(err) {
+      Product.create({ strings: [val] }).then(function() {
+        Product.where({ strings: val }).deleteMany(function(err) {
           assert.ifError(err);
-          Product.findOne({strings: val}, function(err, doc) {
+          Product.findOne({ strings: val }, function(err, doc) {
             assert.ifError(err);
             assert.ok(!doc);
             done();
@@ -1173,10 +1173,10 @@ describe('Query', function() {
       const Product = db.model('Product', productSchema);
       const val = 'remove-cond-and-callback';
 
-      Product.create({strings: [val]}).then(function() {
-        Product.where().deleteMany({strings: val}, function(err) {
+      Product.create({ strings: [val] }).then(function() {
+        Product.where().deleteMany({ strings: val }, function(err) {
           assert.ifError(err);
-          Product.findOne({strings: val}, function(err, doc) {
+          Product.findOne({ strings: val }, function(err, doc) {
             assert.ifError(err);
             assert.ok(!doc);
             done();
@@ -1241,8 +1241,8 @@ describe('Query', function() {
     it('works', function(done) {
       const Product = db.model('Product', productSchema);
 
-      const proddoc = {comments: [{text: 'hello'}]};
-      const prod2doc = {comments: [{text: 'goodbye'}]};
+      const proddoc = { comments: [{ text: 'hello' }] };
+      const prod2doc = { comments: [{ text: 'goodbye' }] };
 
       const prod = new Product(proddoc);
       prod.save(function(err) {
@@ -1256,7 +1256,7 @@ describe('Query', function() {
           Product.updateOne({ _id: prod._id }, prod2doc, function(err) {
             assert.ifError(err);
 
-            Product.collection.findOne({_id: product._id}, function(err, doc) {
+            Product.collection.findOne({ _id: product._id }, function(err, doc) {
               assert.ifError(err);
               assert.equal(doc.comments.length, 1);
               // ensure hidden private props were not saved to db
@@ -1273,7 +1273,7 @@ describe('Query', function() {
   describe('optionsForExec', function() {
     it('should retain key order', function(done) {
       // this is important for query hints
-      const hint = {x: 1, y: 1, z: 1};
+      const hint = { x: 1, y: 1, z: 1 };
       const a = JSON.stringify({ hint: hint });
 
       const q = new Query;
@@ -1363,7 +1363,7 @@ describe('Query', function() {
       });
       it('supports passing the `await` option', function(done) {
         const query = new Query({});
-        query.tailable({awaitdata: true});
+        query.tailable({ awaitdata: true });
         assert.equal(query.options.tailable, true);
         assert.equal(query.options.awaitdata, true);
         done();
@@ -1383,8 +1383,8 @@ describe('Query', function() {
     describe('hint', function() {
       it('works', function(done) {
         const query2 = new Query({});
-        query2.hint({indexAttributeA: 1, indexAttributeB: -1});
-        assert.deepEqual(query2.options.hint, {indexAttributeA: 1, indexAttributeB: -1});
+        query2.hint({ indexAttributeA: 1, indexAttributeB: -1 });
+        assert.deepEqual(query2.options.hint, { indexAttributeA: 1, indexAttributeB: -1 });
 
         const query3 = new Query({});
         query3.hint('indexAttributeA_1');
@@ -1475,7 +1475,7 @@ describe('Query', function() {
       describe('with tags', function() {
         it('works', function(done) {
           const query = new Query({});
-          const tags = [{dc: 'sf', s: 1}, {dc: 'jp', s: 2}];
+          const tags = [{ dc: 'sf', s: 1 }, { dc: 'jp', s: 2 }];
 
           query.read('pp', tags);
           assert.ok(query.options.readPreference instanceof P);
@@ -1493,7 +1493,7 @@ describe('Query', function() {
       describe('inherits its models schema read option', function() {
         let schema, M, called;
         before(function() {
-          schema = new Schema({}, {read: 'p'});
+          schema = new Schema({}, { read: 'p' });
           M = mongoose.model('schemaOptionReadPrefWithQuery', schema);
         });
 
@@ -1512,8 +1512,8 @@ describe('Query', function() {
         });
 
         it('and sends it though the driver', function(done) {
-          const options = {read: 'secondary', safe: {w: 'majority'}};
-          const schema = new Schema({name: String}, options);
+          const options = { read: 'secondary', safe: { w: 'majority' } };
+          const schema = new Schema({ name: String }, options);
           const M = db.model('Test', schema);
           const q = M.find();
 
@@ -1526,7 +1526,7 @@ describe('Query', function() {
 
             assert.ok(ret.readPreference);
             assert.equal(ret.readPreference.mode, 'secondary');
-            assert.deepEqual({w: 'majority'}, ret.safe);
+            assert.deepEqual({ w: 'majority' }, ret.safe);
             called = true;
 
             return ret;
@@ -1588,18 +1588,18 @@ describe('Query', function() {
   describe('setOptions', function() {
     it('works', function(done) {
       const q = new Query;
-      q.setOptions({thing: 'cat'});
-      q.setOptions({populate: ['fans']});
-      q.setOptions({batchSize: 10});
-      q.setOptions({limit: 4});
-      q.setOptions({skip: 3});
-      q.setOptions({sort: '-blah'});
-      q.setOptions({sort: {woot: -1}});
-      q.setOptions({hint: {index1: 1, index2: -1}});
-      q.setOptions({read: ['s', [{dc: 'eu'}]]});
+      q.setOptions({ thing: 'cat' });
+      q.setOptions({ populate: ['fans'] });
+      q.setOptions({ batchSize: 10 });
+      q.setOptions({ limit: 4 });
+      q.setOptions({ skip: 3 });
+      q.setOptions({ sort: '-blah' });
+      q.setOptions({ sort: { woot: -1 } });
+      q.setOptions({ hint: { index1: 1, index2: -1 } });
+      q.setOptions({ read: ['s', [{ dc: 'eu' }]] });
 
       assert.equal(q.options.thing, 'cat');
-      assert.deepEqual(q._mongooseOptions.populate.fans, {path: 'fans', _docs: {}});
+      assert.deepEqual(q._mongooseOptions.populate.fans, { path: 'fans', _docs: {} });
       assert.equal(q.options.batchSize, 10);
       assert.equal(q.options.limit, 4);
       assert.equal(q.options.skip, 3);
@@ -1613,10 +1613,10 @@ describe('Query', function() {
 
       const Product = db.model('Product', productSchema);
       Product.create(
-        {numbers: [3, 4, 5]},
-        {strings: 'hi there'.split(' ')}, function(err, doc1, doc2) {
+        { numbers: [3, 4, 5] },
+        { strings: 'hi there'.split(' ') }, function(err, doc1, doc2) {
           assert.ifError(err);
-          Product.find().setOptions({limit: 1, sort: {_id: -1}, read: 'n'}).exec(function(err, docs) {
+          Product.find().setOptions({ limit: 1, sort: { _id: -1 }, read: 'n' }).exec(function(err, docs) {
             assert.ifError(err);
             assert.equal(docs.length, 1);
             assert.equal(docs[0].id, doc2.id);
@@ -1731,7 +1731,7 @@ describe('Query', function() {
     describe('gh-1950', function() {
       it.skip('ignores sort when passed to count', function(done) {
         const Product = db.model('Product', productSchema);
-        Product.find().sort({_id: 1}).count({}).exec(function(error) {
+        Product.find().sort({ _id: 1 }).count({}).exec(function(error) {
           assert.ifError(error);
           done();
         });
@@ -1740,12 +1740,12 @@ describe('Query', function() {
       it('ignores sort when passed to countDocuments', function() {
         const Product = db.model('Product', productSchema);
         return Product.create({}).
-          then(() => Product.find().sort({_id: 1}).countDocuments({}).exec());
+          then(() => Product.find().sort({ _id: 1 }).countDocuments({}).exec());
       });
 
       it.skip('ignores count when passed to sort', function(done) {
         const Product = db.model('Product', productSchema);
-        Product.find().count({}).sort({_id: 1}).exec(function(error) {
+        Product.find().count({}).sort({ _id: 1 }).exec(function(error) {
           assert.ifError(error);
           done();
         });
@@ -1762,9 +1762,9 @@ describe('Query', function() {
         username: String
       });
 
-      User.create({username: 'Val'}, function(error, user) {
+      User.create({ username: 'Val' }, function(error, user) {
         assert.ifError(error);
-        User.find({_id: user._id}).select('username').exec(function(error, users) {
+        User.find({ _id: user._id }).select('username').exec(function(error, users) {
           assert.ifError(error);
           assert.equal(users.length, 1);
           assert.ok(!users[0]._id);
@@ -1776,14 +1776,14 @@ describe('Query', function() {
 
     it('doesnt reverse key order for update docs (gh-3215)', function(done) {
       const Test = db.model('Test', {
-        arr: [{date: Date, value: Number}]
+        arr: [{ date: Date, value: Number }]
       });
 
       const q = Test.updateOne({}, {
         $push: {
           arr: {
-            $each: [{date: new Date(), value: 1}],
-            $sort: {value: -1, date: -1}
+            $each: [{ date: new Date(), value: 1 }],
+            $sort: { value: -1, date: -1 }
           }
         }
       });
@@ -1847,10 +1847,10 @@ describe('Query', function() {
         }]
       });
 
-      const answersUpdate = {details: 'blah', stats: {votes: 1, count: '3'}};
+      const answersUpdate = { details: 'blah', stats: { votes: 1, count: '3' } };
       const q = Post.updateOne(
-        {'answers._id': '507f1f77bcf86cd799439011'},
-        {$set: {'answers.$': answersUpdate}});
+        { 'answers._id': '507f1f77bcf86cd799439011' },
+        { $set: { 'answers.$': answersUpdate } });
 
       assert.deepEqual(q.getUpdate().$set['answers.$'].stats,
         { votes: 1, count: 3 });
@@ -2105,7 +2105,7 @@ describe('Query', function() {
           return Test.findOne({});
         }).
         then(function(doc) {
-          return Test.findOneAndUpdate({_id: doc._id}, {
+          return Test.findOneAndUpdate({ _id: doc._id }, {
             $set: {
               val: 'another string'
             }
@@ -2461,7 +2461,7 @@ describe('Query', function() {
         bigData[i] = 'test1234567890';
       }
 
-      model.find({email: {$in: bigData}}).lean().
+      model.find({ email: { $in: bigData } }).lean().
         then(function() {
           done(new Error('Expected an error'));
         }).
@@ -2519,15 +2519,15 @@ describe('Query', function() {
         });
 
         const userOwnerSchema = new Schema({
-          id: {type: Schema.Types.ObjectId, required: true}
+          id: { type: Schema.Types.ObjectId, required: true }
         }, { _id: false });
 
         const tagOwnerSchema = new Schema({
-          id: {type: String, required: true}
+          id: { type: String, required: true }
         }, { _id: false });
 
         const activitySchema = new Schema({
-          owner: {type: ownerSchema, required: true}
+          owner: { type: ownerSchema, required: true }
         }, { _id: false });
 
         activitySchema.path('owner').discriminator('user', userOwnerSchema);
@@ -2568,15 +2568,15 @@ describe('Query', function() {
         });
 
         const userOwnerSchema = new Schema({
-          id: {type: Schema.Types.ObjectId, required: true}
+          id: { type: Schema.Types.ObjectId, required: true }
         }, { _id: false });
 
         const tagOwnerSchema = new Schema({
-          id: {type: String, required: true}
+          id: { type: String, required: true }
         }, { _id: false });
 
         const activitySchema = new Schema({
-          owner: {type: ownerSchema, required: true}
+          owner: { type: ownerSchema, required: true }
         }, { _id: false });
 
         activitySchema.path('owner').discriminator('user', userOwnerSchema);
@@ -2642,7 +2642,7 @@ describe('Query', function() {
 
     it('handles geoWithin with mongoose docs (gh-4392)', function(done) {
       const areaSchema = new Schema({
-        name: {type: String},
+        name: { type: String },
         loc: {
           type: {
             type: String,
@@ -2737,7 +2737,7 @@ describe('Query', function() {
           name: String,
           lastName: String,
           dependents: [String],
-          salary: {type: Number, default: 25000}
+          salary: { type: Number, default: 25000 }
         });
 
         db.deleteModel(/Person/);
@@ -2748,7 +2748,7 @@ describe('Query', function() {
     });
 
     it('falsy projection', function(done) {
-      MyModel.findOne({name: 'John'}, {lastName: false}).
+      MyModel.findOne({ name: 'John' }, { lastName: false }).
         exec(function(error, person) {
           assert.ifError(error);
           assert.equal(person.salary, 25000);
@@ -2757,7 +2757,7 @@ describe('Query', function() {
     });
 
     it('slice projection', function(done) {
-      MyModel.findOne({name: 'John'}, {dependents: {$slice: 1}}).exec(function(error, person) {
+      MyModel.findOne({ name: 'John' }, { dependents: { $slice: 1 } }).exec(function(error, person) {
         assert.ifError(error);
         assert.equal(person.salary, 25000);
         done();
@@ -2765,7 +2765,7 @@ describe('Query', function() {
     });
 
     it('empty projection', function(done) {
-      MyModel.findOne({name: 'John'}, {}).
+      MyModel.findOne({ name: 'John' }, {}).
         exec(function(error, person) {
           assert.ifError(error);
           assert.equal(person.salary, 25000);
@@ -3258,7 +3258,7 @@ describe('Query', function() {
 
     it('$set nested property with numeric position', function() {
       return co(function*() {
-        const kids = 'foo bar baz'.split(' ').map(n => { return { name: `${n}`};});
+        const kids = 'foo bar baz'.split(' ').map(n => { return { name: `${n}` };});
         const doc = yield Parent.create({ children: kids });
         assert.ok(doc.children[0].updatedAt && doc.children[0].createdAt);
         assert.ok(doc.children[1].updatedAt && doc.children[1].createdAt);
@@ -3282,7 +3282,7 @@ describe('Query', function() {
 
     it('$set numeric element', function() {
       return co(function*() {
-        const kids = 'foo bar baz'.split(' ').map(n => { return { name: `${n}`};});
+        const kids = 'foo bar baz'.split(' ').map(n => { return { name: `${n}` };});
         const doc = yield Parent.create({ children: kids });
         assert.ok(doc.children[0].updatedAt && doc.children[0].createdAt);
         assert.ok(doc.children[1].updatedAt && doc.children[1].createdAt);
@@ -3305,7 +3305,7 @@ describe('Query', function() {
 
     it('$set with positional operator', function() {
       return co(function*() {
-        const kids = 'foo bar baz'.split(' ').map(n => { return { name: `${n}`};});
+        const kids = 'foo bar baz'.split(' ').map(n => { return { name: `${n}` };});
         const doc = yield Parent.create({ children: kids });
         assert.ok(doc.children[0].updatedAt && doc.children[0].createdAt);
         assert.ok(doc.children[1].updatedAt && doc.children[1].createdAt);
diff --git a/test/query.toconstructor.test.js b/test/query.toconstructor.test.js
index 647278c02cf..05e2e9a2ffc 100644
--- a/test/query.toconstructor.test.js
+++ b/test/query.toconstructor.test.js
@@ -49,7 +49,7 @@ describe('Query:', function() {
 
     it('creates a query', function(done) {
       const Product = db.model(prodName);
-      const prodQ = Product.find({title: /test/}).toConstructor();
+      const prodQ = Product.find({ title: /test/ }).toConstructor();
 
       assert.ok(prodQ() instanceof Query);
       done();
@@ -58,7 +58,7 @@ describe('Query:', function() {
     it('copies all the right values', function(done) {
       const Product = db.model(prodName);
 
-      const prodQ = Product.update({title: /test/}, {title: 'blah'});
+      const prodQ = Product.update({ title: /test/ }, { title: 'blah' });
 
       const prodC = prodQ.toConstructor();
 
@@ -76,9 +76,9 @@ describe('Query:', function() {
 
     it('gets expected results', function(done) {
       const Product = db.model(prodName);
-      Product.create({title: 'this is a test'}, function(err, p) {
+      Product.create({ title: 'this is a test' }, function(err, p) {
         assert.ifError(err);
-        const prodC = Product.find({title: /test/}).toConstructor();
+        const prodC = Product.find({ title: /test/ }).toConstructor();
 
         prodC().exec(function(err, results) {
           assert.ifError(err);
@@ -92,17 +92,17 @@ describe('Query:', function() {
     it('can be re-used multiple times', function(done) {
       const Product = db.model(prodName);
 
-      Product.create([{title: 'moar thing'}, {title: 'second thing'}], function(err, prods) {
+      Product.create([{ title: 'moar thing' }, { title: 'second thing' }], function(err, prods) {
         assert.ifError(err);
         assert.equal(prods.length, 2);
         const prod = prods[0];
-        const prodC = Product.find({title: /thing/}).toConstructor();
+        const prodC = Product.find({ title: /thing/ }).toConstructor();
 
         prodC().exec(function(err, results) {
           assert.ifError(err);
 
           assert.equal(results.length, 2);
-          prodC().find({_id: prod.id}).exec(function(err, res) {
+          prodC().find({ _id: prod.id }).exec(function(err, res) {
             assert.ifError(err);
             assert.equal(res.length, 1);
 
@@ -119,13 +119,13 @@ describe('Query:', function() {
     it('options get merged properly', function(done) {
       const Product = db.model(prodName);
 
-      let prodC = Product.find({title: /blah/}).setOptions({sort: 'title', lean: true});
+      let prodC = Product.find({ title: /blah/ }).setOptions({ sort: 'title', lean: true });
       prodC = prodC.toConstructor();
 
-      const nq = prodC(null, {limit: 3});
-      assert.deepEqual(nq._mongooseOptions, {lean: true, limit: 3});
+      const nq = prodC(null, { limit: 3 });
+      assert.deepEqual(nq._mongooseOptions, { lean: true, limit: 3 });
       assert.deepEqual(nq.options, {
-        sort: {title: 1},
+        sort: { title: 1 },
         limit: 3
       });
       done();
@@ -134,18 +134,18 @@ describe('Query:', function() {
     it('options get cloned (gh-3176)', function(done) {
       const Product = db.model(prodName);
 
-      let prodC = Product.find({title: /blah/}).setOptions({sort: 'title', lean: true});
+      let prodC = Product.find({ title: /blah/ }).setOptions({ sort: 'title', lean: true });
       prodC = prodC.toConstructor();
 
-      const nq = prodC(null, {limit: 3});
-      assert.deepEqual(nq._mongooseOptions, {lean: true, limit: 3});
+      const nq = prodC(null, { limit: 3 });
+      assert.deepEqual(nq._mongooseOptions, { lean: true, limit: 3 });
       assert.deepEqual(nq.options, {
-        sort: {title: 1},
+        sort: { title: 1 },
         limit: 3
       });
-      const nq2 = prodC(null, {limit: 5});
-      assert.deepEqual(nq._mongooseOptions, {lean: true, limit: 3});
-      assert.deepEqual(nq2._mongooseOptions, {lean: true, limit: 5});
+      const nq2 = prodC(null, { limit: 5 });
+      assert.deepEqual(nq._mongooseOptions, { lean: true, limit: 3 });
+      assert.deepEqual(nq2._mongooseOptions, { lean: true, limit: 5 });
 
       done();
     });
@@ -153,10 +153,10 @@ describe('Query:', function() {
     it('creates subclasses of mquery', function(done) {
       const Product = db.model(prodName);
 
-      const opts = {safe: {w: 'majority'}, readPreference: 'p'};
-      const match = {title: 'test', count: {$gt: 101}};
-      const select = {name: 1, count: 0};
-      const update = {$set: {title: 'thing'}};
+      const opts = { safe: { w: 'majority' }, readPreference: 'p' };
+      const match = { title: 'test', count: { $gt: 101 } };
+      const select = { name: 1, count: 0 };
+      const update = { $set: { title: 'thing' } };
       const path = 'title';
 
       const q = Product.update(match, update);
diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index 2e4eefd68af..b2feeb0854e 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -31,7 +31,7 @@ describe('schema alias option', function() {
       buffer: { type: Buffer, alias: 'BufferAlias' },
       boolean: { type: Boolean, alias: 'BooleanAlias' },
       mixed: { type: Schema.Types.Mixed, alias: 'MixedAlias' },
-      objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias'},
+      objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias' },
       array: { type: [], alias: 'ArrayAlias' }
     });
 
@@ -70,7 +70,7 @@ describe('schema alias option', function() {
         buffer: { type: Buffer, alias: 'BufferAlias' },
         boolean: { type: Boolean, alias: 'BooleanAlias' },
         mixed: { type: Schema.Types.Mixed, alias: 'MixedAlias' },
-        objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias'},
+        objectId: { type: Schema.Types.ObjectId, alias: 'ObjectIdAlias' },
         array: { type: [], alias: 'ArrayAlias' }
       }
     });
diff --git a/test/schema.boolean.test.js b/test/schema.boolean.test.js
index 9d15ef88604..682d8932760 100644
--- a/test/schema.boolean.test.js
+++ b/test/schema.boolean.test.js
@@ -24,11 +24,11 @@ describe('schematype', function() {
 
   describe('boolean', function() {
     it('null default is permitted (gh-523)', function(done) {
-      const s1 = new Schema({b: {type: Boolean, default: null}});
+      const s1 = new Schema({ b: { type: Boolean, default: null } });
       const M1 = db.model('NullDateDefaultIsAllowed1', s1);
-      const s2 = new Schema({b: {type: Boolean, default: false}});
+      const s2 = new Schema({ b: { type: Boolean, default: false } });
       const M2 = db.model('NullDateDefaultIsAllowed2', s2);
-      const s3 = new Schema({b: {type: Boolean, default: true}});
+      const s3 = new Schema({ b: { type: Boolean, default: true } });
       const M3 = db.model('NullDateDefaultIsAllowed3', s3);
 
       const m1 = new M1;
@@ -41,7 +41,7 @@ describe('schematype', function() {
     });
 
     it('strictBool option (gh-5211)', function(done) {
-      const s1 = new Schema({b: {type: Boolean}});
+      const s1 = new Schema({ b: { type: Boolean } });
       const M1 = db.model('StrictBoolOption', s1);
 
       const strictValues = [true, false, 'true', 'false', 0, 1, '0', '1', 'no', 'yes'];
@@ -63,7 +63,7 @@ describe('schematype', function() {
     });
 
     it('strictBool schema option', function(done) {
-      const s1 = new Schema({b: {type: Boolean}}, {strictBool: true});
+      const s1 = new Schema({ b: { type: Boolean } }, { strictBool: true });
       const M1 = db.model('StrictBoolTrue', s1);
 
       const strictValues = [true, false, 'true', 'false', 0, 1, '0', '1'];
diff --git a/test/schema.documentarray.test.js b/test/schema.documentarray.test.js
index e0cc59b8a87..983bf9634de 100644
--- a/test/schema.documentarray.test.js
+++ b/test/schema.documentarray.test.js
@@ -17,14 +17,14 @@ const Schema = mongoose.Schema;
 
 describe('schema.documentarray', function() {
   it('defaults should be preserved', function(done) {
-    const child = new Schema({title: String});
+    const child = new Schema({ title: String });
 
-    const schema1 = new Schema({x: {type: [child], default: [{title: 'Prometheus'}]}});
-    const schema2 = new Schema({x: {type: [child], default: {title: 'Prometheus'}}});
+    const schema1 = new Schema({ x: { type: [child], default: [{ title: 'Prometheus' }] } });
+    const schema2 = new Schema({ x: { type: [child], default: { title: 'Prometheus' } } });
     const schema3 = new Schema({
       x: {
         type: [child], default: function() {
-          return [{title: 'Prometheus'}];
+          return [{ title: 'Prometheus' }];
         }
       }
     });
@@ -44,19 +44,19 @@ describe('schema.documentarray', function() {
 
   it('only sets if document has same schema (gh-3701)', function(done) {
     const schema1 = new Schema({
-      arr: [new Schema({a: Number, b: Number}, {_id: false})]
+      arr: [new Schema({ a: Number, b: Number }, { _id: false })]
     });
     const schema2 = new Schema({
-      arr: [new Schema({a: Number}, {_id: false})]
+      arr: [new Schema({ a: Number }, { _id: false })]
     });
 
     const Model1 = mongoose.model('gh3701_0', schema1);
     const Model2 = mongoose.model('gh3701_1', schema2);
 
-    const source = new Model1({arr: [{a: 1, b: 1}, {a: 2, b: 2}]});
-    const dest = new Model2({arr: source.arr});
+    const source = new Model1({ arr: [{ a: 1, b: 1 }, { a: 2, b: 2 }] });
+    const dest = new Model2({ arr: source.arr });
 
-    assert.deepEqual(dest.toObject().arr, [{a: 1}, {a: 2}]);
+    assert.deepEqual(dest.toObject().arr, [{ a: 1 }, { a: 2 }]);
     done();
   });
 
@@ -86,11 +86,11 @@ describe('schema.documentarray', function() {
 
     const Nested = mongoose.model('gh7799', nestedSchema);
 
-    const doc = new Nested({nested: [[{ title: 'cool' }, { title: 'not cool' }]]});
+    const doc = new Nested({ nested: [[{ title: 'cool' }, { title: 'not cool' }]] });
     assert.equal(doc.nested[0].length, 2);
     assert.equal(doc.nested[0][0].title, 'cool');
 
-    doc.set({nested: [[{ title: 'new' }]]});
+    doc.set({ nested: [[{ title: 'new' }]] });
     assert.equal(doc.nested[0].length, 1);
     assert.equal(doc.nested[0][0].title, 'new');
 
diff --git a/test/schema.mixed.test.js b/test/schema.mixed.test.js
index 6a5fc1b97b3..e826af14895 100644
--- a/test/schema.mixed.test.js
+++ b/test/schema.mixed.test.js
@@ -14,7 +14,7 @@ const Schema = mongoose.Schema;
 describe('schematype mixed', function() {
   describe('empty object defaults (gh-1380)', function() {
     it('are interpreted as fns that return new empty objects', function(done) {
-      const s = new Schema({mix: {type: Schema.Types.Mixed, default: {}}});
+      const s = new Schema({ mix: { type: Schema.Types.Mixed, default: {} } });
       const M = mongoose.model('M1', s);
       const m1 = new M;
       const m2 = new M;
@@ -25,7 +25,7 @@ describe('schematype mixed', function() {
     });
     it('can be forced to share the object between documents', function(done) {
       // silly but necessary for backwards compatibility
-      const s = new Schema({mix: {type: Schema.Types.Mixed, default: {}, shared: true}});
+      const s = new Schema({ mix: { type: Schema.Types.Mixed, default: {}, shared: true } });
       const M = mongoose.model('M2', s);
       const m1 = new M;
       const m2 = new M;
diff --git a/test/schema.onthefly.test.js b/test/schema.onthefly.test.js
index d20ed690a65..b8b73a18ce2 100644
--- a/test/schema.onthefly.test.js
+++ b/test/schema.onthefly.test.js
@@ -17,7 +17,7 @@ describe('schema.onthefly', function() {
   before(function() {
     DecoratedSchema = new Schema({
       title: String
-    }, {strict: false});
+    }, { strict: false });
 
     mongoose.model('Decorated', DecoratedSchema);
     db = start();
@@ -54,7 +54,7 @@ describe('schema.onthefly', function() {
   it('querying a document that had an on the fly schema should work', function(done) {
     const Decorated = db.model('Decorated', collection);
 
-    const post = new Decorated({title: 'AD HOC'});
+    const post = new Decorated({ title: 'AD HOC' });
     // Interpret adhoc as a Number
     post.set('adhoc', '9', Number);
     assert.equal(post.get('adhoc').valueOf(), 9);
@@ -92,7 +92,7 @@ describe('schema.onthefly', function() {
     const Decorated = db.model('Decorated', collection);
 
     const post = new Decorated();
-    post.set('moderators', [{name: 'alex trebek'}], [new Schema({name: String})]);
+    post.set('moderators', [{ name: 'alex trebek' }], [new Schema({ name: String })]);
     assert.equal(post.get('moderators')[0].name, 'alex trebek');
     done();
   });
@@ -101,9 +101,9 @@ describe('schema.onthefly', function() {
     const Decorated = db.model('Decorated', collection);
 
     const post = new Decorated();
-    const ModeratorSchema = new Schema({name: String, ranking: Number});
+    const ModeratorSchema = new Schema({ name: String, ranking: Number });
 
-    post.set('moderators', [{name: 'alex trebek', ranking: '1'}], [ModeratorSchema]);
+    post.set('moderators', [{ name: 'alex trebek', ranking: '1' }], [ModeratorSchema]);
     assert.equal(post.get('moderators')[0].name, 'alex trebek');
     post.save(function(err) {
       assert.ifError(err);
@@ -115,7 +115,7 @@ describe('schema.onthefly', function() {
         let rankingPostCast = found.get('moderators', [ModeratorSchema])[0].ranking;
         assert.equal(rankingPostCast, 1);
 
-        const NewModeratorSchema = new Schema({name: String, ranking: String});
+        const NewModeratorSchema = new Schema({ name: String, ranking: String });
         rankingPostCast = found.get('moderators', [NewModeratorSchema])[0].ranking;
         assert.equal(rankingPostCast, 1);
         done();
@@ -126,7 +126,7 @@ describe('schema.onthefly', function() {
   it('casts on get() (gh-2360)', function(done) {
     const Decorated = db.model('gh2360', DecoratedSchema, 'gh2360');
 
-    const d = new Decorated({title: '1'});
+    const d = new Decorated({ title: '1' });
     assert.equal(typeof d.get('title', Number), 'number');
 
     d.title = '000000000000000000000001';
diff --git a/test/schema.select.test.js b/test/schema.select.test.js
index f88c8e3a3db..410ec78877b 100644
--- a/test/schema.select.test.js
+++ b/test/schema.select.test.js
@@ -27,12 +27,12 @@ describe('schema select option', function() {
   it('excluding paths through schematype', function(done) {
     const schema = new Schema({
       thin: Boolean,
-      name: {type: String, select: false},
-      docs: [new Schema({bool: Boolean, name: {type: String, select: false}})]
+      name: { type: String, select: false },
+      docs: [new Schema({ bool: Boolean, name: { type: String, select: false } })]
     });
 
     const S = db.model('ExcludingBySchemaType', schema);
-    S.create({thin: true, name: 'the excluded', docs: [{bool: true, name: 'test'}]}, function(err, s) {
+    S.create({ thin: true, name: 'the excluded', docs: [{ bool: true, name: 'test' }] }, function(err, s) {
       assert.ifError(err);
       assert.equal(s.name, 'the excluded');
       assert.equal(s.docs[0].name, 'test');
@@ -52,7 +52,7 @@ describe('schema select option', function() {
         assert.strictEqual(undefined, s.name);
         // we need to make sure this executes absolutely last.
         if (pending === 1) {
-          S.findOneAndRemove({_id: item._id}, cb);
+          S.findOneAndRemove({ _id: item._id }, cb);
         }
         if (pending === 0) {
           done();
@@ -60,21 +60,21 @@ describe('schema select option', function() {
       }
 
       S.findById(s).select('-thin -docs.bool').exec(cb);
-      S.find({_id: s._id}).select('thin docs.bool').exec(cb);
+      S.find({ _id: s._id }).select('thin docs.bool').exec(cb);
       S.findById(s, cb);
-      S.findOneAndUpdate({_id: s._id}, {name: 'changed'}, cb);
+      S.findOneAndUpdate({ _id: s._id }, { name: 'changed' }, cb);
     });
   });
 
   it('including paths through schematype', function(done) {
     const schema = new Schema({
       thin: Boolean,
-      name: {type: String, select: true},
-      docs: [new Schema({bool: Boolean, name: {type: String, select: true}})]
+      name: { type: String, select: true },
+      docs: [new Schema({ bool: Boolean, name: { type: String, select: true } })]
     });
 
     const S = db.model('IncludingBySchemaType', schema);
-    S.create({thin: true, name: 'the included', docs: [{bool: true, name: 'test'}]}, function(err, s) {
+    S.create({ thin: true, name: 'the included', docs: [{ bool: true, name: 'test' }] }, function(err, s) {
       assert.ifError(err);
       assert.equal(s.name, 'the included');
       assert.equal(s.docs[0].name, 'test');
@@ -99,11 +99,11 @@ describe('schema select option', function() {
 
       S.findById(s).select('-thin -docs.bool').exec(function(err, res) {
         cb(err, res);
-        S.find({_id: s._id}).select('thin docs.bool').exec(function(err, res) {
+        S.find({ _id: s._id }).select('thin docs.bool').exec(function(err, res) {
           cb(err, res);
-          S.findOneAndUpdate({_id: s._id}, {thin: false}, function(err, s) {
+          S.findOneAndUpdate({ _id: s._id }, { thin: false }, function(err, s) {
             cb(err, s);
-            S.findOneAndRemove({_id: s._id}, cb);
+            S.findOneAndRemove({ _id: s._id }, cb);
           });
         });
       });
@@ -116,13 +116,13 @@ describe('schema select option', function() {
     before(function() {
       selected = new Schema({
         thin: Boolean,
-        name: {type: String, select: true},
-        docs: [new Schema({name: {type: String, select: true}, bool: Boolean})]
+        name: { type: String, select: true },
+        docs: [new Schema({ name: { type: String, select: true }, bool: Boolean })]
       });
       excluded = new Schema({
         thin: Boolean,
-        name: {type: String, select: false},
-        docs: [new Schema({name: {type: String, select: false}, bool: Boolean})]
+        name: { type: String, select: false },
+        docs: [new Schema({ name: { type: String, select: false }, bool: Boolean })]
       });
 
       S = db.model('OverriddingSelectedBySchemaType', selected);
@@ -133,7 +133,7 @@ describe('schema select option', function() {
       describe('for inclusions', function() {
         let s;
         before(function(done) {
-          S.create({thin: true, name: 'the included', docs: [{name: 'test', bool: true}]}, function(err, s_) {
+          S.create({ thin: true, name: 'the included', docs: [{ name: 'test', bool: true }] }, function(err, s_) {
             assert.ifError(err);
             s = s_;
             assert.equal(s.name, 'the included');
@@ -142,7 +142,7 @@ describe('schema select option', function() {
           });
         });
         it('with find', function(done) {
-          S.find({_id: s._id}).select('thin name docs.bool docs.name').exec(function(err, s) {
+          S.find({ _id: s._id }).select('thin name docs.bool docs.name').exec(function(err, s) {
             assert.ifError(err);
             assert.ok(s && s.length > 0, 'no document found');
             s = s[0];
@@ -173,7 +173,7 @@ describe('schema select option', function() {
           });
         });
         it('with findOneAndUpdate', function(done) {
-          S.findOneAndUpdate({_id: s._id}, {name: 'changed'}, {new: true}).select('thin name docs.bool docs.name').exec(function(err, s) {
+          S.findOneAndUpdate({ _id: s._id }, { name: 'changed' }, { new: true }).select('thin name docs.bool docs.name').exec(function(err, s) {
             assert.ifError(err);
             assert.strictEqual(true, s.isSelected('name'));
             assert.strictEqual(true, s.isSelected('thin'));
@@ -187,7 +187,7 @@ describe('schema select option', function() {
           });
         });
         it('for findByIdAndUpdate', function(done) {
-          S.findByIdAndUpdate(s, {thin: false}, {new: true}).select('-name -docs.name').exec(function(err, s) {
+          S.findByIdAndUpdate(s, { thin: false }, { new: true }).select('-name -docs.name').exec(function(err, s) {
             assert.strictEqual(null, err);
             assert.equal(s.isSelected('name'), false);
             assert.equal(s.isSelected('thin'), true);
@@ -205,7 +205,7 @@ describe('schema select option', function() {
       describe('for exclusions', function() {
         let e;
         before(function(done) {
-          E.create({thin: true, name: 'the excluded', docs: [{name: 'test', bool: true}]}, function(err, e_) {
+          E.create({ thin: true, name: 'the excluded', docs: [{ name: 'test', bool: true }] }, function(err, e_) {
             e = e_;
             assert.ifError(err);
             assert.equal(e.name, 'the excluded');
@@ -214,7 +214,7 @@ describe('schema select option', function() {
           });
         });
         it('with find', function(done) {
-          E.find({_id: e._id}).select('thin name docs.name docs.bool').exec(function(err, e) {
+          E.find({ _id: e._id }).select('thin name docs.name docs.bool').exec(function(err, e) {
             e = e[0];
             assert.strictEqual(null, err);
             assert.equal(e.isSelected('name'), true);
@@ -243,7 +243,7 @@ describe('schema select option', function() {
           });
         });
         it('with findOneAndUpdate', function(done) {
-          E.findOneAndUpdate({_id: e._id}, {name: 'changed'}, {new: true}).select('thin name docs.name docs.bool').exec(function(err, e) {
+          E.findOneAndUpdate({ _id: e._id }, { name: 'changed' }, { new: true }).select('thin name docs.name docs.bool').exec(function(err, e) {
             assert.strictEqual(null, err);
             assert.equal(e.isSelected('name'), true);
             assert.equal(e.isSelected('thin'), true);
@@ -257,7 +257,7 @@ describe('schema select option', function() {
           });
         });
         it('with findOneAndRemove', function(done) {
-          E.findOneAndRemove({_id: e._id}).select('-name -docs.name').exec(function(err, e) {
+          E.findOneAndRemove({ _id: e._id }).select('-name -docs.name').exec(function(err, e) {
             assert.strictEqual(null, err);
             assert.equal(e.isSelected('name'), false);
             assert.equal(e.isSelected('thin'), true);
@@ -278,11 +278,11 @@ describe('schema select option', function() {
     it('works (gh-1333)', function(done) {
       const m = new mongoose.Mongoose();
       const child = new Schema({
-        name1: {type: String, select: false},
-        name2: {type: String, select: true}
+        name1: { type: String, select: false },
+        name2: { type: String, select: true }
       });
       const selected = new Schema({
-        docs: {type: [child], select: false}
+        docs: { type: [child], select: false }
       });
       const M = m.model('gh-1333-deselect', selected);
 
@@ -297,12 +297,12 @@ describe('schema select option', function() {
 
     it('with nested (gh-7945)', function() {
       const child = new Schema({
-        name1: {type: String, select: false},
-        name2: {type: String, select: true}
+        name1: { type: String, select: false },
+        name2: { type: String, select: true }
       });
       const selected = new Schema({
         parent: {
-          docs: {type: [child], select: false}
+          docs: { type: [child], select: false }
         }
       });
       const M = db.model('gh7945', selected);
@@ -326,12 +326,12 @@ describe('schema select option', function() {
     it('works', function(done) {
       const excluded = new Schema({
         thin: Boolean,
-        name: {type: String, select: false},
-        docs: [new Schema({name: {type: String, select: false}, bool: Boolean})]
+        name: { type: String, select: false },
+        docs: [new Schema({ name: { type: String, select: false }, bool: Boolean })]
       });
 
       const M = db.model('ForcedInclusionOfPath', excluded);
-      M.create({thin: false, name: '1 meter', docs: [{name: 'test', bool: false}]}, function(err, d) {
+      M.create({ thin: false, name: '1 meter', docs: [{ name: 'test', bool: false }] }, function(err, d) {
         assert.ifError(err);
 
         M.findById(d)
@@ -382,9 +382,9 @@ describe('schema select option', function() {
     });
 
     it('works with query.slice (gh-1370)', function(done) {
-      const M = db.model('1370', new Schema({many: {type: [String], select: false}}));
+      const M = db.model('1370', new Schema({ many: { type: [String], select: false } }));
 
-      M.create({many: ['1', '2', '3', '4', '5']}, function(err) {
+      M.create({ many: ['1', '2', '3', '4', '5'] }, function(err) {
         if (err) {
           return done(err);
         }
@@ -444,12 +444,12 @@ describe('schema select option', function() {
   it('conflicting schematype path selection should not error', function(done) {
     const schema = new Schema({
       thin: Boolean,
-      name: {type: String, select: true},
-      conflict: {type: String, select: false}
+      name: { type: String, select: true },
+      conflict: { type: String, select: false }
     });
 
     const S = db.model('ConflictingBySchemaType', schema);
-    S.create({thin: true, name: 'bing', conflict: 'crosby'}, function(err, s) {
+    S.create({ thin: true, name: 'bing', conflict: 'crosby' }, function(err, s) {
       assert.strictEqual(null, err);
       assert.equal(s.name, 'bing');
       assert.equal(s.conflict, 'crosby');
@@ -469,13 +469,13 @@ describe('schema select option', function() {
       }
 
       S.findById(s).exec(cb);
-      S.find({_id: s._id}).exec(cb);
+      S.find({ _id: s._id }).exec(cb);
     });
   });
 
   it('selecting _id works with excluded schematype path', function(done) {
     const schema = new Schema({
-      name: {type: String, select: false}
+      name: { type: String, select: false }
     });
 
     const M = db.model('SelectingOnly_idWithExcludedSchemaType', schema);
@@ -491,7 +491,7 @@ describe('schema select option', function() {
 
   it('selecting _id works with excluded schematype path on sub doc', function(done) {
     const schema = new Schema({
-      docs: [new Schema({name: {type: String, select: false}})]
+      docs: [new Schema({ name: { type: String, select: false } })]
     });
 
     const M = db.model('SelectingOnly_idWithExcludedSchemaTypeSubDoc', schema);
@@ -509,21 +509,21 @@ describe('schema select option', function() {
     const coll = 'inclusiveexclusivecomboswork_' + random();
 
     const schema = new Schema({
-      name: {type: String},
+      name: { type: String },
       age: Number
-    }, {collection: coll});
+    }, { collection: coll });
     const M = db.model('InclusiveExclusiveCombosWork', schema);
 
     const schema1 = new Schema({
-      name: {type: String, select: false},
+      name: { type: String, select: false },
       age: Number
-    }, {collection: coll});
+    }, { collection: coll });
     const S = db.model('InclusiveExclusiveCombosWorkWithSchemaSelectionFalse', schema1);
 
     const schema2 = new Schema({
-      name: {type: String, select: true},
+      name: { type: String, select: true },
       age: Number
-    }, {collection: coll});
+    }, { collection: coll });
     const T = db.model('InclusiveExclusiveCombosWorkWithSchemaSelectionTrue', schema2);
 
     function useId(M, id, cb) {
@@ -577,7 +577,7 @@ describe('schema select option', function() {
       });
     }
 
-    M.create({name: 'ssd', age: 0}, function(err, d) {
+    M.create({ name: 'ssd', age: 0 }, function(err, d) {
       assert.ifError(err);
       const id = d.id;
       useId(M, id, function() {
@@ -661,7 +661,7 @@ describe('schema select option', function() {
   it('initializes nested defaults with selected objects (gh-2629)', function(done) {
     const NestedSchema = new mongoose.Schema({
       nested: {
-        name: {type: String, default: 'val'}
+        name: { type: String, default: 'val' }
       }
     });
 
@@ -671,7 +671,7 @@ describe('schema select option', function() {
     doc.nested.name = undefined;
     doc.save(function(error) {
       assert.ifError(error);
-      Model.findOne({}, {nested: 1}, function(error, doc) {
+      Model.findOne({}, { nested: 1 }, function(error, doc) {
         assert.ifError(error);
         assert.equal(doc.nested.name, 'val');
         done();
diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
index 9a43be927b8..5365776f587 100644
--- a/test/schema.singlenestedpath.test.js
+++ b/test/schema.singlenestedpath.test.js
@@ -20,7 +20,7 @@ describe('SingleNestedPath', function() {
 
         const subEventSchema = new Schema({
           sub_events: [singleEventSchema]
-        }, {_id: false});
+        }, { _id: false });
 
         subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
 
@@ -40,7 +40,7 @@ describe('SingleNestedPath', function() {
 
         const subEventSchema = new Schema({
           sub_events: [singleEventSchema]
-        }, {_id: false});
+        }, { _id: false });
 
         subEventSchema.path('sub_events').discriminator('SubEvent', subEventSchema);
 
diff --git a/test/schema.test.js b/test/schema.test.js
index 963db49f2e7..3ffe4fdef58 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2133,14 +2133,14 @@ describe('schema', function() {
 
   it('getters/setters with clone() (gh-8124)', function() {
     const schema = new mongoose.Schema({
-      field: {type: String, required: true}
+      field: { type: String, required: true }
     });
 
     schema.path('field').set(value => value ? value.toUpperCase() : value);
 
     const TestKo = db.model('Test', schema.clone());
 
-    const testKo = new TestKo({field: 'upper'});
+    const testKo = new TestKo({ field: 'upper' });
     assert.equal(testKo.field, 'UPPER');
   });
 
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index d11e4379e62..2f3c37ab093 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -175,13 +175,13 @@ describe('schema options.timestamps', function() {
       CatSchema = new Schema({
         name: String,
         hobby: String
-      }, {timestamps: true});
+      }, { timestamps: true });
       Cat = conn.model('Cat', CatSchema);
-      return Cat.deleteMany({}).then(() => Cat.create({name: 'newcat'}));
+      return Cat.deleteMany({}).then(() => Cat.create({ name: 'newcat' }));
     });
 
     it('should have fields when create', function(done) {
-      const cat = new Cat({name: 'newcat'});
+      const cat = new Cat({ name: 'newcat' });
       cat.save(function(err, doc) {
         assert.ok(doc.createdAt);
         assert.ok(doc.updatedAt);
@@ -191,7 +191,7 @@ describe('schema options.timestamps', function() {
     });
 
     it('should have fields when create with findOneAndUpdate', function(done) {
-      Cat.findOneAndUpdate({name: 'notexistname'}, {$set: {}}, {upsert: true, new: true}, function(err, doc) {
+      Cat.findOneAndUpdate({ name: 'notexistname' }, { $set: {} }, { upsert: true, new: true }, function(err, doc) {
         assert.ok(doc.createdAt);
         assert.ok(doc.updatedAt);
         assert.ok(doc.createdAt.getTime() === doc.updatedAt.getTime());
@@ -200,7 +200,7 @@ describe('schema options.timestamps', function() {
     });
 
     it('should change updatedAt when save', function(done) {
-      Cat.findOne({name: 'newcat'}, function(err, doc) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
         const old = doc.updatedAt;
 
         doc.hobby = 'coding';
@@ -213,7 +213,7 @@ describe('schema options.timestamps', function() {
     });
 
     it('should not change updatedAt when save with no modifications', function(done) {
-      Cat.findOne({name: 'newcat'}, function(err, doc) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
         const old = doc.updatedAt;
 
         doc.save(function(err, doc) {
@@ -240,11 +240,11 @@ describe('schema options.timestamps', function() {
     });
 
     it('should change updatedAt when findOneAndUpdate', function(done) {
-      Cat.create({name: 'test123'}, function(err) {
+      Cat.create({ name: 'test123' }, function(err) {
         assert.ifError(err);
-        Cat.findOne({name: 'test123'}, function(err, doc) {
+        Cat.findOne({ name: 'test123' }, function(err, doc) {
           const old = doc.updatedAt;
-          Cat.findOneAndUpdate({name: 'test123'}, {$set: {hobby: 'fish'}}, {new: true}, function(err, doc) {
+          Cat.findOneAndUpdate({ name: 'test123' }, { $set: { hobby: 'fish' } }, { new: true }, function(err, doc) {
             assert.ok(doc.updatedAt.getTime() > old.getTime());
             done();
           });
@@ -284,10 +284,10 @@ describe('schema options.timestamps', function() {
     });
 
     it('should have fields when update', function(done) {
-      Cat.findOne({name: 'newcat'}, function(err, doc) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
         const old = doc.updatedAt;
-        Cat.update({name: 'newcat'}, {$set: {hobby: 'fish'}}, function() {
-          Cat.findOne({name: 'newcat'}, function(err, doc) {
+        Cat.update({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
+          Cat.findOne({ name: 'newcat' }, function(err, doc) {
             assert.ok(doc.updatedAt.getTime() > old.getTime());
             done();
           });
@@ -296,10 +296,10 @@ describe('schema options.timestamps', function() {
     });
 
     it('should change updatedAt when updateOne', function(done) {
-      Cat.findOne({name: 'newcat'}, function(err, doc) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
         const old = doc.updatedAt;
-        Cat.updateOne({name: 'newcat'}, {$set: {hobby: 'fish'}}, function() {
-          Cat.findOne({name: 'newcat'}, function(err, doc) {
+        Cat.updateOne({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
+          Cat.findOne({ name: 'newcat' }, function(err, doc) {
             assert.ok(doc.updatedAt.getTime() > old.getTime());
             done();
           });
@@ -308,10 +308,10 @@ describe('schema options.timestamps', function() {
     });
 
     it('should change updatedAt when updateMany', function(done) {
-      Cat.findOne({name: 'newcat'}, function(err, doc) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
         const old = doc.updatedAt;
-        Cat.updateMany({name: 'newcat'}, {$set: {hobby: 'fish'}}, function() {
-          Cat.findOne({name: 'newcat'}, function(err, doc) {
+        Cat.updateMany({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
+          Cat.findOne({ name: 'newcat' }, function(err, doc) {
             assert.ok(doc.updatedAt.getTime() > old.getTime());
             done();
           });
diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index 570b6e48660..c2929b8fb1f 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -23,25 +23,25 @@ describe('schema', function() {
     it('invalid arguments are rejected (1044)', function(done) {
       assert.throws(function() {
         new Schema({
-          simple: {type: String, validate: 'nope'}
+          simple: { type: String, validate: 'nope' }
         });
       }, /Invalid validator/);
 
       assert.throws(function() {
         new Schema({
-          simple: {type: String, validate: ['nope']}
+          simple: { type: String, validate: ['nope'] }
         });
       }, /Invalid validator/);
 
       assert.throws(function() {
         new Schema({
-          simple: {type: String, validate: {nope: 1, msg: 'nope'}}
+          simple: { type: String, validate: { nope: 1, msg: 'nope' } }
         });
       }, /Invalid validator/);
 
       assert.throws(function() {
         new Schema({
-          simple: {type: String, validate: [{nope: 1, msg: 'nope'}, 'nope']}
+          simple: { type: String, validate: [{ nope: 1, msg: 'nope' }, 'nope'] }
         });
       }, /Invalid validator/);
 
@@ -50,8 +50,8 @@ describe('schema', function() {
 
     it('string enum', function(done) {
       const Test = new Schema({
-        complex: {type: String, enum: ['a', 'b', undefined, 'c', null]},
-        state: {type: String}
+        complex: { type: String, enum: ['a', 'b', undefined, 'c', null] },
+        state: { type: String }
       });
 
       assert.ok(Test.path('complex') instanceof SchemaTypes.String);
@@ -107,7 +107,7 @@ describe('schema', function() {
 
     it('string regexp', function(done) {
       const Test = new Schema({
-        simple: {type: String, match: /[a-z]/}
+        simple: { type: String, match: /[a-z]/ }
       });
 
       assert.equal(Test.path('simple').validators.length, 1);
@@ -158,8 +158,8 @@ describe('schema', function() {
         before(function() {
           db = start();
           const PersonSchema = new Schema({
-            name: {type: String},
-            num_cars: {type: Number, min: 20}
+            name: { type: String },
+            num_cars: { type: Number, min: 20 }
           });
           Person = db.model('person-schema-validation-test', PersonSchema);
         });
@@ -169,7 +169,7 @@ describe('schema', function() {
         });
 
         it('and can be set to "undefined" (gh-1594)', function(done) {
-          const p = new Person({name: 'Daniel'});
+          const p = new Person({ name: 'Daniel' });
           p.num_cars = 25;
 
           p.save(function(err) {
@@ -194,7 +194,7 @@ describe('schema', function() {
 
       it('number min and max', function(done) {
         const Tobi = new Schema({
-          friends: {type: Number, max: 15, min: 5}
+          friends: { type: Number, max: 15, min: 5 }
         });
 
         assert.equal(Tobi.path('friends').validators.length, 2);
@@ -309,7 +309,7 @@ describe('schema', function() {
 
       it('number required', function(done) {
         const Edwald = new Schema({
-          friends: {type: Number, required: true}
+          friends: { type: Number, required: true }
         });
 
         Edwald.path('friends').doValidate(null, function(err) {
@@ -329,7 +329,7 @@ describe('schema', function() {
 
       it('date required', function(done) {
         const Loki = new Schema({
-          birth_date: {type: Date, required: true}
+          birth_date: { type: Date, required: true }
         });
 
         Loki.path('birth_date').doValidate(null, function(err) {
@@ -349,7 +349,7 @@ describe('schema', function() {
 
       it('date not empty string (gh-3132)', function(done) {
         const HappyBirthday = new Schema({
-          date: {type: Date, required: true}
+          date: { type: Date, required: true }
         });
 
         HappyBirthday.path('date').doValidate('', function(err) {
@@ -360,7 +360,7 @@ describe('schema', function() {
 
       it('objectid required', function(done) {
         const Loki = new Schema({
-          owner: {type: ObjectId, required: true}
+          owner: { type: ObjectId, required: true }
         });
 
         Loki.path('owner').doValidate(new DocumentObjectId(), function(err) {
@@ -379,7 +379,7 @@ describe('schema', function() {
 
       it('array required', function(done) {
         const Loki = new Schema({
-          likes: {type: Array, required: true}
+          likes: { type: Array, required: true }
         });
 
         let remaining = 2;
@@ -404,7 +404,7 @@ describe('schema', function() {
         };
 
         const Loki = new Schema({
-          likes: {type: Array, required: true}
+          likes: { type: Array, required: true }
         });
 
         let remaining = 2;
@@ -422,7 +422,7 @@ describe('schema', function() {
 
       it('boolean required', function(done) {
         const Animal = new Schema({
-          isFerret: {type: Boolean, required: true}
+          isFerret: { type: Boolean, required: true }
         });
 
         let remaining = 4;
@@ -450,7 +450,7 @@ describe('schema', function() {
 
       it('mixed required', function(done) {
         const Animal = new Schema({
-          characteristics: {type: Mixed, required: true}
+          characteristics: { type: Mixed, required: true }
         });
 
         let remaining = 4;
@@ -496,7 +496,7 @@ describe('schema', function() {
         }
 
         const Animal = new Schema({
-          ferret: {type: Boolean, validate: validator}
+          ferret: { type: Boolean, validate: validator }
         });
 
         Animal.path('ferret').doValidate(true, function(err) {
@@ -568,7 +568,7 @@ describe('schema', function() {
           assert.ifError(err);
           assert.equal(called, true);
           done();
-        }, {a: 'b'});
+        }, { a: 'b' });
       });
     });
 
@@ -576,16 +576,16 @@ describe('schema', function() {
       describe('are customizable', function() {
         it('within schema definitions', function(done) {
           const schema = new Schema({
-            name: {type: String, enum: ['one', 'two']},
-            myenum: {type: String, enum: {values: ['x'], message: 'enum validator failed for path: {PATH} with {VALUE}'}},
-            requiredString1: {type: String, required: true},
-            requiredString2: {type: String, required: 'oops, {PATH} is missing. {TYPE}'},
-            matchString0: {type: String, match: /bryancranston/},
-            matchString1: {type: String, match: [/bryancranston/, 'invalid string for {PATH} with value: {VALUE}']},
-            numMin0: {type: Number, min: 10},
-            numMin1: {type: Number, min: [10, 'hey, {PATH} is too small']},
-            numMax0: {type: Number, max: 20},
-            numMax1: {type: Number, max: [20, 'hey, {PATH} ({VALUE}) is greater than {MAX}']}
+            name: { type: String, enum: ['one', 'two'] },
+            myenum: { type: String, enum: { values: ['x'], message: 'enum validator failed for path: {PATH} with {VALUE}' } },
+            requiredString1: { type: String, required: true },
+            requiredString2: { type: String, required: 'oops, {PATH} is missing. {TYPE}' },
+            matchString0: { type: String, match: /bryancranston/ },
+            matchString1: { type: String, match: [/bryancranston/, 'invalid string for {PATH} with value: {VALUE}'] },
+            numMin0: { type: Number, min: 10 },
+            numMin1: { type: Number, min: [10, 'hey, {PATH} is too small'] },
+            numMax0: { type: Number, max: 20 },
+            numMax1: { type: Number, max: [20, 'hey, {PATH} ({VALUE}) is greater than {MAX}'] }
           });
 
           const A = mongoose.model('schema-validation-messages-' + random(), schema);
@@ -628,10 +628,10 @@ describe('schema', function() {
           };
           const validator = [validate, '{PATH} failed validation ({VALUE})'];
 
-          const schema = new Schema({x: {type: [], validate: validator}});
+          const schema = new Schema({ x: { type: [], validate: validator } });
           const M = mongoose.model('custom-validator-' + random(), schema);
 
-          const m = new M({x: [3, 4, 5, 6]});
+          const m = new M({ x: [3, 4, 5, 6] });
 
           m.validate(function(err) {
             assert.equal(String(err.errors.x), 'x failed validation (3,4,5,6)');
@@ -657,7 +657,7 @@ describe('schema', function() {
           });
           const M = mongoose.model('custom-validator-async-' + random(), schema);
 
-          const m = new M({x: 'test'});
+          const m = new M({ x: 'test' });
 
           m.validate(function(err) {
             assert.ok(err.errors['x']);
@@ -684,7 +684,7 @@ describe('schema', function() {
           });
           const M = mongoose.model('gh5125', schema);
 
-          const m = new M({x: 'test'});
+          const m = new M({ x: 'test' });
 
           m.validate(function(err) {
             assert.ok(err.errors['x']);
@@ -710,7 +710,7 @@ describe('schema', function() {
           });
           const M = mongoose.model('gh5171', schema);
 
-          const m = new M({x: 'not test'});
+          const m = new M({ x: 'not test' });
 
           m.validate(function(err) {
             assert.ok(err.errors['x']);
@@ -733,7 +733,7 @@ describe('schema', function() {
           });
           const M = mongoose.model('gh-2132', schema, 'gh-2132');
 
-          const m = new M({x: 'a'});
+          const m = new M({ x: 'a' });
           m.validate(function(err) {
             assert.equal(err.errors.x.toString(), 'Error code 25');
             assert.equal(err.errors.x.properties.message, 'Error code 25');
@@ -756,7 +756,7 @@ describe('schema', function() {
           });
           const M = mongoose.model('gh-1936', schema, 'gh-1936');
 
-          const m = new M({x: 'whatever'});
+          const m = new M({ x: 'whatever' });
           m.validate(function(err) {
             assert.equal(err.errors.x.toString(), 'Custom message');
             done();
@@ -774,10 +774,10 @@ describe('schema', function() {
 
           const validator = [validate, '{PATH} failed validation ({VALUE})', 'customType'];
 
-          const schema = new Schema({x: {type: [], validate: validator}});
+          const schema = new Schema({ x: { type: [], validate: validator } });
           const M = mongoose.model('custom-validator-' + random(), schema);
 
-          const m = new M({x: [3, 4, 5, 6]});
+          const m = new M({ x: [3, 4, 5, 6] });
 
           m.validate(function(err) {
             assert.equal(String(err.errors.x), 'x failed validation (3,4,5,6)');
@@ -793,12 +793,12 @@ describe('schema', function() {
           }
 
           const validator = [
-            {validator: validate, msg: '{PATH} failed validation ({VALUE})', type: 'customType'}
+            { validator: validate, msg: '{PATH} failed validation ({VALUE})', type: 'customType' }
           ];
-          const schema = new Schema({x: {type: [], validate: validator}});
+          const schema = new Schema({ x: { type: [], validate: validator } });
           const M = mongoose.model('custom-validator-' + random(), schema);
 
-          const m = new M({x: [3, 4, 5, 6]});
+          const m = new M({ x: [3, 4, 5, 6] });
 
           m.validate(function(err) {
             assert.equal(String(err.errors.x), 'x failed validation (3,4,5,6)');
@@ -810,7 +810,7 @@ describe('schema', function() {
     });
 
     it('should clear validator errors (gh-2302)', function(done) {
-      const userSchema = new Schema({name: {type: String, required: true}});
+      const userSchema = new Schema({ name: { type: String, required: true } });
       const User = mongoose.model('gh-2302', userSchema, 'gh-2302');
 
       const user = new User();
@@ -830,15 +830,15 @@ describe('schema', function() {
     it('should allow an array of enums (gh-661)', function(done) {
       const validBreakfastFoods = ['bacon', 'eggs', 'steak', 'coffee', 'butter'];
       const breakfastSchema = new Schema({
-        foods: [{type: String, enum: validBreakfastFoods}]
+        foods: [{ type: String, enum: validBreakfastFoods }]
       });
       const Breakfast = mongoose.model('gh-661', breakfastSchema, 'gh-661');
 
-      const goodBreakfast = new Breakfast({foods: ['eggs', 'bacon']});
+      const goodBreakfast = new Breakfast({ foods: ['eggs', 'bacon'] });
       goodBreakfast.validate(function(error) {
         assert.ifError(error);
 
-        const badBreakfast = new Breakfast({foods: ['tofu', 'waffles', 'coffee']});
+        const badBreakfast = new Breakfast({ foods: ['tofu', 'waffles', 'coffee'] });
         badBreakfast.validate(function(error) {
           assert.ok(error);
           assert.ok(error.errors['foods.0']);
@@ -857,7 +857,7 @@ describe('schema', function() {
     it('should allow an array of subdocuments with enums (gh-3521)', function(done) {
       const coolSchema = new Schema({
         votes: [{
-          vote: {type: String, enum: ['cool', 'not-cool']}
+          vote: { type: String, enum: ['cool', 'not-cool'] }
         }]
       });
       const Cool = mongoose.model('gh-3521', coolSchema, 'gh-3521');
@@ -924,8 +924,8 @@ describe('schema', function() {
     });
 
     it('doesnt do double validation on document arrays (gh-2618)', function(done) {
-      const A = new Schema({str: String});
-      let B = new Schema({a: [A]});
+      const A = new Schema({ str: String });
+      let B = new Schema({ a: [A] });
       let validateCalls = 0;
       B.path('a').validate(function() {
         ++validateCalls;
@@ -935,7 +935,7 @@ describe('schema', function() {
       B = mongoose.model('b', B);
 
       const p = new B();
-      p.a.push({str: 'asdf'});
+      p.a.push({ str: 'asdf' });
       p.validate(function(err) {
         assert.ifError(err);
         assert.equal(validateCalls, 1);
@@ -957,7 +957,7 @@ describe('schema', function() {
               value: {
                 type: Boolean,
                 required: false,
-                validate: {validator: myValidator}
+                validate: { validator: myValidator }
               }
             })]
           }
@@ -1040,7 +1040,7 @@ describe('schema', function() {
       });
       const Breakfast = mongoose.model('gh-2611', breakfastSchema, 'gh-2611');
 
-      const bad = new Breakfast({eggs: 'none'});
+      const bad = new Breakfast({ eggs: 'none' });
       bad.validate(function(error) {
         assert.ok(error);
         done();
@@ -1048,11 +1048,11 @@ describe('schema', function() {
     });
 
     it('handles multiple subdocument errors (gh-2589)', function(done) {
-      const foodSchema = new Schema({name: {type: String, required: true, enum: ['bacon', 'eggs']}});
-      const breakfast = new Schema({foods: [foodSchema], id: Number});
+      const foodSchema = new Schema({ name: { type: String, required: true, enum: ['bacon', 'eggs'] } });
+      const breakfast = new Schema({ foods: [foodSchema], id: Number });
 
       const Breakfast = mongoose.model('gh-2589', breakfast, 'gh-2589');
-      const bad = new Breakfast({foods: [{name: 'tofu'}, {name: 'waffles'}], id: 'Not a number'});
+      const bad = new Breakfast({ foods: [{ name: 'tofu' }, { name: 'waffles' }], id: 'Not a number' });
       bad.validate(function(error) {
         assert.ok(error);
         assert.deepEqual(['id', 'foods.0.name', 'foods.1.name'], Object.keys(error.errors));
@@ -1061,26 +1061,26 @@ describe('schema', function() {
     });
 
     it('handles subdocument cast errors (gh-2819)', function(done) {
-      const foodSchema = new Schema({eggs: {type: Number, required: true}});
-      const breakfast = new Schema({foods: [foodSchema], id: Number});
+      const foodSchema = new Schema({ eggs: { type: Number, required: true } });
+      const breakfast = new Schema({ foods: [foodSchema], id: Number });
 
       const Breakfast = mongoose.model('gh-2819', breakfast, 'gh-2819');
 
       // Initially creating subdocs with cast errors
-      const bad = new Breakfast({foods: [{eggs: 'Not a number'}], id: 'Not a number'});
+      const bad = new Breakfast({ foods: [{ eggs: 'Not a number' }], id: 'Not a number' });
       bad.validate(function(error) {
         assert.ok(error);
         assert.deepEqual(['foods.0.eggs', 'id'], Object.keys(error.errors).sort());
         assert.ok(error.errors['foods.0.eggs'] instanceof mongoose.Error.CastError);
 
         // Pushing docs with cast errors
-        bad.foods.push({eggs: 'Also not a number'});
+        bad.foods.push({ eggs: 'Also not a number' });
         bad.validate(function(error) {
           assert.deepEqual(['foods.0.eggs', 'foods.1.eggs', 'id'], Object.keys(error.errors).sort());
           assert.ok(error.errors['foods.1.eggs'] instanceof mongoose.Error.CastError);
 
           // Splicing docs with cast errors
-          bad.foods.splice(1, 1, {eggs: 'fail1'}, {eggs: 'fail2'});
+          bad.foods.splice(1, 1, { eggs: 'fail1' }, { eggs: 'fail2' });
           bad.validate(function(error) {
             assert.deepEqual(['foods.0.eggs', 'foods.1.eggs', 'foods.2.eggs', 'id'], Object.keys(error.errors).sort());
             assert.ok(error.errors['foods.0.eggs'] instanceof mongoose.Error.CastError);
@@ -1095,7 +1095,7 @@ describe('schema', function() {
               assert.ok(error.errors['foods.1.eggs'] instanceof mongoose.Error.CastError);
 
               // Remove the cast error using array.set()
-              bad.foods.set(1, {eggs: 1});
+              bad.foods.set(1, { eggs: 1 });
               bad.validate(function(error) {
                 assert.deepEqual(['foods.0.eggs', 'id'], Object.keys(error.errors).sort());
                 assert.ok(error.errors['foods.0.eggs'] instanceof mongoose.Error.CastError);
@@ -1109,7 +1109,7 @@ describe('schema', function() {
     });
 
     it('fails when you try to set a nested path to a primitive (gh-2592)', function(done) {
-      const breakfast = new Schema({foods: {bacon: Number, eggs: Number}});
+      const breakfast = new Schema({ foods: { bacon: Number, eggs: Number } });
 
       const Breakfast = mongoose.model('gh-2592', breakfast, 'gh-2592');
 
@@ -1125,7 +1125,7 @@ describe('schema', function() {
     });
 
     it('doesnt execute other validators if required fails (gh-2725)', function(done) {
-      const breakfast = new Schema({description: {type: String, required: true, maxlength: 50}});
+      const breakfast = new Schema({ description: { type: String, required: true, maxlength: 50 } });
 
       const Breakfast = mongoose.model('gh2725', breakfast, 'gh2725');
       const bad = new Breakfast({});
@@ -1138,7 +1138,7 @@ describe('schema', function() {
     });
 
     it('doesnt execute other validators if required fails (gh-3025)', function(done) {
-      const breakfast = new Schema({description: {type: String, required: true, maxlength: 50}});
+      const breakfast = new Schema({ description: { type: String, required: true, maxlength: 50 } });
 
       const Breakfast = mongoose.model('gh3025', breakfast, 'gh3025');
       const bad = new Breakfast({});
@@ -1152,8 +1152,8 @@ describe('schema', function() {
 
     it('validateSync allows you to filter paths (gh-3153)', function(done) {
       const breakfast = new Schema({
-        description: {type: String, required: true, maxlength: 50},
-        other: {type: String, required: true}
+        description: { type: String, required: true, maxlength: 50 },
+        other: { type: String, required: true }
       });
 
       const Breakfast = mongoose.model('gh3153', breakfast, 'gh3153');
@@ -1168,7 +1168,7 @@ describe('schema', function() {
     });
 
     it('adds required validators to the front of the list (gh-2843)', function(done) {
-      const breakfast = new Schema({description: {type: String, maxlength: 50, required: true}});
+      const breakfast = new Schema({ description: { type: String, maxlength: 50, required: true } });
 
       const Breakfast = mongoose.model('gh2843', breakfast, 'gh2843');
       const bad = new Breakfast({});
@@ -1190,7 +1190,7 @@ describe('schema', function() {
       });
 
       const Breakfast = mongoose.model('gh2832', breakfast, 'gh2832');
-      Breakfast.create({description: undefined}, function(error) {
+      Breakfast.create({ description: undefined }, function(error) {
         assert.ok(error);
         const errorMessage = 'ValidationError: description: Cast to String failed for value "undefined" at path "description"';
         assert.equal(errorMessage, error.toString());
@@ -1202,13 +1202,13 @@ describe('schema', function() {
 
     it('allows you to validate embedded doc that was .create()-ed (gh-2902) (gh-2929)', function(done) {
       const parentSchema = mongoose.Schema({
-        children: [{name: {type: String, required: true}}]
+        children: [{ name: { type: String, required: true } }]
       });
 
       const Parent = mongoose.model('gh2902', parentSchema);
 
       const p = new Parent();
-      const n = p.children.create({name: '2'});
+      const n = p.children.create({ name: '2' });
       n.validate(function(error) {
         assert.ifError(error);
         const bad = p.children.create({});
@@ -1233,7 +1233,7 @@ describe('schema', function() {
       });
       const M = mongoose.model('gh2885', s);
 
-      const m = new M({n: 'test'});
+      const m = new M({ n: 'test' });
       m.validate(function(error) {
         assert.ok(error);
         assert.equal(error.errors.n.kind, 'user defined');
@@ -1242,10 +1242,10 @@ describe('schema', function() {
     });
 
     it('enums report kind (gh-3009)', function(done) {
-      const s = mongoose.Schema({n: {type: String, enum: ['a', 'b']}});
+      const s = mongoose.Schema({ n: { type: String, enum: ['a', 'b'] } });
       const M = mongoose.model('gh3009', s);
 
-      const m = new M({n: 'test'});
+      const m = new M({ n: 'test' });
       m.validate(function(error) {
         assert.ok(error);
         assert.equal(error.errors.n.kind, 'enum');
diff --git a/test/schematype.test.js b/test/schematype.test.js
index 2b474d42ef9..ddfcbadf552 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -12,40 +12,40 @@ const Schema = mongoose.Schema;
 
 describe('schematype', function() {
   it('honors the selected option', function(done) {
-    const s = new Schema({thought: {type: String, select: false}});
+    const s = new Schema({ thought: { type: String, select: false } });
     assert.ok(!s.path('thought').selected);
 
-    const a = new Schema({thought: {type: String, select: true}});
+    const a = new Schema({ thought: { type: String, select: true } });
     assert.ok(a.path('thought').selected);
     done();
   });
 
   it('properly handles specifying index in combination with unique or sparse', function(done) {
-    let s = new Schema({name: {type: String, index: true, unique: true}});
-    assert.deepEqual(s.path('name')._index, {unique: true});
-    s = new Schema({name: {type: String, unique: true, index: true}});
-    assert.deepEqual(s.path('name')._index, {unique: true});
-    s = new Schema({name: {type: String, index: true, sparse: true}});
-    assert.deepEqual(s.path('name')._index, {sparse: true});
-    s = new Schema({name: {type: String, sparse: true, index: true}});
-    assert.deepEqual(s.path('name')._index, {sparse: true});
+    let s = new Schema({ name: { type: String, index: true, unique: true } });
+    assert.deepEqual(s.path('name')._index, { unique: true });
+    s = new Schema({ name: { type: String, unique: true, index: true } });
+    assert.deepEqual(s.path('name')._index, { unique: true });
+    s = new Schema({ name: { type: String, index: true, sparse: true } });
+    assert.deepEqual(s.path('name')._index, { sparse: true });
+    s = new Schema({ name: { type: String, sparse: true, index: true } });
+    assert.deepEqual(s.path('name')._index, { sparse: true });
     done();
   });
 
   it('handles index: false with unique, sparse, text set to false (gh-7620)', function(done) {
-    let s = new Schema({name: {type: String, index: false, unique: false}});
+    let s = new Schema({ name: { type: String, index: false, unique: false } });
     assert.equal(s.path('name')._index, false);
-    s = new Schema({name: {type: String, unique: false, index: false}});
+    s = new Schema({ name: { type: String, unique: false, index: false } });
     assert.equal(s.path('name')._index, false);
 
-    s = new Schema({name: {type: String, index: false, sparse: false}});
+    s = new Schema({ name: { type: String, index: false, sparse: false } });
     assert.equal(s.path('name')._index, false);
-    s = new Schema({name: {type: String, sparse: false, index: false}});
+    s = new Schema({ name: { type: String, sparse: false, index: false } });
     assert.equal(s.path('name')._index, false);
 
-    s = new Schema({name: {type: String, index: false, text: false}});
+    s = new Schema({ name: { type: String, index: false, text: false } });
     assert.equal(s.path('name')._index, false);
-    s = new Schema({name: {type: String, text: false, index: false}});
+    s = new Schema({ name: { type: String, text: false, index: false } });
     assert.equal(s.path('name')._index, false);
 
     done();
@@ -213,7 +213,7 @@ describe('schematype', function() {
       it(type.name + ', when given a default option, set its', () => {
         // Act
         type.set('someRandomOption', true);
-        const schema = new mongoose.Schema({test: type});
+        const schema = new mongoose.Schema({ test: type });
 
         // Assert
         assert.equal(schema.path('test').options.someRandomOption, true);
diff --git a/test/shard.test.js b/test/shard.test.js
index b70aff23fb2..9a5c4dc7e0d 100644
--- a/test/shard.test.js
+++ b/test/shard.test.js
@@ -28,11 +28,11 @@ const schema = new Schema({
   name: String,
   age: Number,
   likes: [String]
-}, {shardkey: {name: 1, age: 1}});
+}, { shardkey: { name: 1, age: 1 } });
 
 // to keep mongodb happy when sharding the collection
 // we add a matching index
-schema.index({name: 1, age: 1});
+schema.index({ name: 1, age: 1 });
 
 const collection = 'shardperson_' + random();
 mongoose.model('ShardPerson', schema, collection);
@@ -42,7 +42,7 @@ let greaterThan20x;
 let db;
 describe('shard', function() {
   before(function(done) {
-    db = start({uri: uri});
+    db = start({ uri: uri });
     db.on('error', function(err) {
       if (/failed to connect/.test(err)) {
         err.message = 'Shard test error: '
@@ -83,10 +83,10 @@ describe('shard', function() {
   });
 
   it('can read and write to a shard', function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
 
-    P.create({name: 'ryu', age: 25, likes: ['street fighting']}, function(err, ryu) {
+    P.create({ name: 'ryu', age: 25, likes: ['street fighting'] }, function(err, ryu) {
       assert.ifError(err);
       P.findById(ryu._id, function(err, doc) {
         db.close();
@@ -98,10 +98,10 @@ describe('shard', function() {
   });
 
   it('save() and remove() works with shard keys transparently', function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
 
-    const zangief = new P({name: 'Zangief', age: 33});
+    const zangief = new P({ name: 'Zangief', age: 33 });
     zangief.save(function(err) {
       assert.ifError(err);
 
@@ -138,12 +138,12 @@ describe('shard', function() {
   });
 
   it('inserting to a sharded collection without the full shard key fails', function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
 
     let pending = 6;
 
-    P.create({name: 'ryu', likes: ['street fighting']}, function(err) {
+    P.create({ name: 'ryu', likes: ['street fighting'] }, function(err) {
       assert.ok(err);
       assert.ok(err.message);
       if (!--pending) {
@@ -152,7 +152,7 @@ describe('shard', function() {
       }
     });
 
-    P.create({likes: ['street fighting']}, function(err) {
+    P.create({ likes: ['street fighting'] }, function(err) {
       assert.ok(err);
       assert.ok(err.message);
       if (!--pending) {
@@ -161,7 +161,7 @@ describe('shard', function() {
       }
     });
 
-    P.create({name: 'ryu'}, function(err) {
+    P.create({ name: 'ryu' }, function(err) {
       assert.ok(err);
       assert.ok(err.message);
       if (!--pending) {
@@ -170,7 +170,7 @@ describe('shard', function() {
       }
     });
 
-    P.create({age: 49}, function(err) {
+    P.create({ age: 49 }, function(err) {
       assert.ok(err);
       assert.ok(err.message);
       if (!--pending) {
@@ -179,7 +179,7 @@ describe('shard', function() {
       }
     });
 
-    P.create({likes: ['street fighting'], age: 8}, function(err) {
+    P.create({ likes: ['street fighting'], age: 8 }, function(err) {
       assert.ok(err);
       assert.ok(err.message);
       if (!--pending) {
@@ -200,16 +200,16 @@ describe('shard', function() {
   });
 
   it('updating a sharded collection without the full shard key fails', function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
 
-    P.create({name: 'ken', age: 27}, function(err, ken) {
+    P.create({ name: 'ken', age: 27 }, function(err, ken) {
       assert.ifError(err);
 
-      P.update({name: 'ken'}, {likes: ['kicking', 'punching']}, function(err) {
+      P.update({ name: 'ken' }, { likes: ['kicking', 'punching'] }, function(err) {
         assert.ok(/shard key/.test(err.message));
 
-        P.update({_id: ken._id, name: 'ken'}, {likes: ['kicking', 'punching']}, function(err) {
+        P.update({ _id: ken._id, name: 'ken' }, { likes: ['kicking', 'punching'] }, function(err) {
           // mongo 2.0.x returns: can't do non-multi update with query that doesn't have a valid shard key
           if (greaterThan20x) {
             assert.ok(!err, err);
@@ -217,7 +217,7 @@ describe('shard', function() {
             assert.ok(/shard key/.test(err.message));
           }
 
-          P.update({_id: ken._id, age: 27}, {likes: ['kicking', 'punching']}, function(err) {
+          P.update({ _id: ken._id, age: 27 }, { likes: ['kicking', 'punching'] }, function(err) {
             // mongo 2.0.x returns: can't do non-multi update with query that doesn't have a valid shard key
             if (greaterThan20x) {
               assert.ok(!err, err);
@@ -225,7 +225,7 @@ describe('shard', function() {
               assert.ok(/shard key/.test(err.message));
             }
 
-            P.update({age: 27}, {likes: ['kicking', 'punching']}, function(err) {
+            P.update({ age: 27 }, { likes: ['kicking', 'punching'] }, function(err) {
               db.close();
               assert.ok(err);
               done();
@@ -237,9 +237,9 @@ describe('shard', function() {
   });
 
   it('updating shard key values fails', function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
-    P.create({name: 'chun li', age: 19, likes: ['street fighting']}, function(err, chunli) {
+    P.create({ name: 'chun li', age: 19, likes: ['street fighting'] }, function(err, chunli) {
       assert.ifError(err);
 
       assert.equal(chunli.$__.shardval.name, 'chun li');
@@ -270,10 +270,10 @@ describe('shard', function() {
   });
 
   it('allows null shard key values', function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
 
-    P.create({name: null, age: 27}, function(err, ken) {
+    P.create({ name: null, age: 27 }, function(err, ken) {
       assert.ifError(err);
       P.findById(ken, function(err) {
         assert.ifError(err);
@@ -283,7 +283,7 @@ describe('shard', function() {
   });
 
   after(function(done) {
-    const db = start({uri: uri});
+    const db = start({ uri: uri });
     const P = db.model('ShardPerson', collection);
     P.collection.drop(function() {
       db.close();
diff --git a/test/types.array.test.js b/test/types.array.test.js
index 46dae50a947..0a768393666 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -95,10 +95,10 @@ describe('types array', function() {
       const User = db.model('User', UserSchema);
       const Pet = db.model('Pet', PetSchema);
 
-      const tj = new User({name: 'tj'});
-      const tobi = new Pet({name: 'tobi'});
-      const loki = new Pet({name: 'loki'});
-      const jane = new Pet({name: 'jane'});
+      const tj = new User({ name: 'tj' });
+      const tobi = new Pet({ name: 'tobi' });
+      const loki = new Pet({ name: 'loki' });
+      const jane = new Pet({ name: 'jane' });
 
       tj.pets.push(tobi);
       tj.pets.push(loki);
@@ -111,7 +111,7 @@ describe('types array', function() {
           assert.ifError(err);
           tj.save(function(err) {
             assert.ifError(err);
-            User.findOne({name: 'tj'}, function(err, user) {
+            User.findOne({ name: 'tj' }, function(err, user) {
               assert.ifError(err);
               assert.equal(user.pets.length, 3);
               assert.equal(user.pets.indexOf(tobi.id), 0);
@@ -139,10 +139,10 @@ describe('types array', function() {
       const User = db.model('User', UserSchema);
       const Pet = db.model('Pet', PetSchema);
 
-      const tj = new User({name: 'tj'});
-      const tobi = new Pet({name: 'tobi'});
-      const loki = new Pet({name: 'loki'});
-      const jane = new Pet({name: 'jane'});
+      const tj = new User({ name: 'tj' });
+      const tobi = new Pet({ name: 'tobi' });
+      const loki = new Pet({ name: 'loki' });
+      const jane = new Pet({ name: 'jane' });
 
       tj.pets.push(tobi);
       tj.pets.push(loki);
@@ -155,7 +155,7 @@ describe('types array', function() {
           assert.ifError(err);
           tj.save(function(err) {
             assert.ifError(err);
-            User.findOne({name: 'tj'}, function(err, user) {
+            User.findOne({ name: 'tj' }, function(err, user) {
               assert.ifError(err);
               assert.equal(user.pets.length, 3);
               assert.equal(user.pets.includes(tobi.id), true);
@@ -189,8 +189,8 @@ describe('types array', function() {
     }
 
     it('works with numbers', function(done) {
-      const N = db.model('Test', Schema({arr: [Number]}));
-      const m = new N({arr: [3, 4, 5, 6]});
+      const N = db.model('Test', Schema({ arr: [Number] }));
+      const m = new N({ arr: [3, 4, 5, 6] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 4);
@@ -213,8 +213,8 @@ describe('types array', function() {
     });
 
     it('works with strings', function(done) {
-      const S = db.model('Test', Schema({arr: [String]}));
-      const m = new S({arr: [3, 4, 5, 6]});
+      const S = db.model('Test', Schema({ arr: [String] }));
+      const m = new S({ arr: [3, 4, 5, 6] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 4);
@@ -237,8 +237,8 @@ describe('types array', function() {
     });
 
     it('works with buffers', function(done) {
-      const B = db.model('Test', Schema({arr: [Buffer]}));
-      const m = new B({arr: [[0], Buffer.alloc(1)]});
+      const B = db.model('Test', Schema({ arr: [Buffer] }));
+      const m = new B({ arr: [[0], Buffer.alloc(1)] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
@@ -263,9 +263,9 @@ describe('types array', function() {
     });
 
     it('works with mixed', function(done) {
-      const M = db.model('Test', Schema({arr: []}));
+      const M = db.model('Test', Schema({ arr: [] }));
 
-      const m = new M({arr: [3, {x: 1}, 'yes', [5]]});
+      const m = new M({ arr: [3, { x: 1 }, 'yes', [5]] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 4);
@@ -312,13 +312,13 @@ describe('types array', function() {
     });
 
     it('works with sub-docs', function(done) {
-      const D = db.model('Test', Schema({arr: [{name: String}]}));
+      const D = db.model('Test', Schema({ arr: [{ name: String }] }));
 
-      const m = new D({arr: [{name: 'aaron'}, {name: 'moombahton '}]});
+      const m = new D({ arr: [{ name: 'aaron' }, { name: 'moombahton ' }] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
-        doc.arr.push({name: 'Restrepo'});
+        doc.arr.push({ name: 'Restrepo' });
         assert.equal(doc.arr.length, 3);
         assert.equal(doc.arr[2].name, 'Restrepo');
 
@@ -344,7 +344,7 @@ describe('types array', function() {
         }]
       }));
 
-      const m = new ST({arr: ['ONE', 'TWO']});
+      const m = new ST({ arr: ['ONE', 'TWO'] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
@@ -368,10 +368,10 @@ describe('types array', function() {
 
   describe('splice()', function() {
     it('works', function(done) {
-      const schema = new Schema({numbers: [Number]});
+      const schema = new Schema({ numbers: [Number] });
       const A = db.model('Test', schema);
 
-      const a = new A({numbers: [4, 5, 6, 7]});
+      const a = new A({ numbers: [4, 5, 6, 7] });
       a.save(function(err) {
         assert.ifError(err);
         A.findById(a._id, function(err, doc) {
@@ -397,10 +397,10 @@ describe('types array', function() {
     });
 
     it('on embedded docs', function(done) {
-      const schema = new Schema({types: [new Schema({type: String})]});
+      const schema = new Schema({ types: [new Schema({ type: String })] });
       const A = db.model('Test', schema);
 
-      const a = new A({types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}]});
+      const a = new A({ types: [{ type: 'bird' }, { type: 'boy' }, { type: 'frog' }, { type: 'cloud' }] });
       a.save(function(err) {
         assert.ifError(err);
         A.findById(a._id, function(err, doc) {
@@ -435,14 +435,14 @@ describe('types array', function() {
   describe('unshift()', function() {
     it('works', function(done) {
       const schema = new Schema({
-        types: [new Schema({type: String})],
+        types: [new Schema({ type: String })],
         nums: [Number],
         strs: [String]
       });
       const A = db.model('Test', schema);
 
       const a = new A({
-        types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}],
+        types: [{ type: 'bird' }, { type: 'boy' }, { type: 'frog' }, { type: 'cloud' }],
         nums: [1, 2, 3],
         strs: 'one two three'.split(' ')
       });
@@ -452,7 +452,7 @@ describe('types array', function() {
         A.findById(a._id, function(err, doc) {
           assert.ifError(err);
 
-          const tlen = doc.types.unshift({type: 'tree'});
+          const tlen = doc.types.unshift({ type: 'tree' });
           const nlen = doc.nums.unshift(0);
           const slen = doc.strs.unshift('zero');
 
@@ -460,7 +460,7 @@ describe('types array', function() {
           assert.equal(nlen, 4);
           assert.equal(slen, 4);
 
-          doc.types.push({type: 'worm'});
+          doc.types.push({ type: 'worm' });
           let obj = doc.types.toObject();
           assert.equal(obj[0].type, 'tree');
           assert.equal(obj[1].type, 'bird');
@@ -519,7 +519,7 @@ describe('types array', function() {
           lowercase: true
         }]
       }));
-      const m = new ST({arr: ['ONE', 'TWO']});
+      const m = new ST({ arr: ['ONE', 'TWO'] });
       m.save(function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
@@ -544,7 +544,7 @@ describe('types array', function() {
   describe('shift()', function() {
     it('works', function(done) {
       const schema = new Schema({
-        types: [new Schema({type: String})],
+        types: [new Schema({ type: String })],
         nums: [Number],
         strs: [String]
       });
@@ -552,7 +552,7 @@ describe('types array', function() {
       const A = db.model('Test', schema);
 
       const a = new A({
-        types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}],
+        types: [{ type: 'bird' }, { type: 'boy' }, { type: 'frog' }, { type: 'cloud' }],
         nums: [1, 2, 3],
         strs: 'one two three'.split(' ')
       });
@@ -614,9 +614,9 @@ describe('types array', function() {
   describe('$shift', function() {
     it('works', function(done) {
       // atomic shift uses $pop -1
-      const painting = new Schema({colors: []});
+      const painting = new Schema({ colors: [] });
       const Painting = db.model('Test', painting);
-      const p = new Painting({colors: ['blue', 'green', 'yellow']});
+      const p = new Painting({ colors: ['blue', 'green', 'yellow'] });
       p.save(function(err) {
         assert.ifError(err);
 
@@ -654,7 +654,7 @@ describe('types array', function() {
   describe('pop()', function() {
     it('works', function(done) {
       const schema = new Schema({
-        types: [new Schema({type: String})],
+        types: [new Schema({ type: String })],
         nums: [Number],
         strs: [String]
       });
@@ -662,7 +662,7 @@ describe('types array', function() {
       const A = db.model('Test', schema);
 
       const a = new A({
-        types: [{type: 'bird'}, {type: 'boy'}, {type: 'frog'}, {type: 'cloud'}],
+        types: [{ type: 'bird' }, { type: 'boy' }, { type: 'frog' }, { type: 'cloud' }],
         nums: [1, 2, 3],
         strs: 'one two three'.split(' ')
       });
@@ -723,17 +723,17 @@ describe('types array', function() {
 
   describe('pull()', function() {
     it('works', function(done) {
-      const catschema = new Schema({name: String});
+      const catschema = new Schema({ name: String });
       const Cat = db.model('Cat', catschema);
       const schema = new Schema({
-        a: [{type: Schema.ObjectId, ref: 'Cat'}]
+        a: [{ type: Schema.ObjectId, ref: 'Cat' }]
       });
       const A = db.model('Test', schema);
-      const cat = new Cat({name: 'peanut'});
+      const cat = new Cat({ name: 'peanut' });
       cat.save(function(err) {
         assert.ifError(err);
 
-        const a = new A({a: [cat._id]});
+        const a = new A({ a: [cat._id] });
         a.save(function(err) {
           assert.ifError(err);
 
@@ -752,7 +752,7 @@ describe('types array', function() {
       const personSchema = new Schema({
         name: String,
         role: String
-      }, {_id: false});
+      }, { _id: false });
       const bandSchema = new Schema({
         name: String,
         members: [personSchema]
@@ -763,17 +763,17 @@ describe('types array', function() {
       const gnr = new Band({
         name: 'Guns N\' Roses',
         members: [
-          {name: 'Axl', role: 'Lead Singer'},
-          {name: 'Slash', role: 'Guitar'},
-          {name: 'Izzy', role: 'Guitar'},
-          {name: 'Duff', role: 'Bass'},
-          {name: 'Adler', role: 'Drums'}
+          { name: 'Axl', role: 'Lead Singer' },
+          { name: 'Slash', role: 'Guitar' },
+          { name: 'Izzy', role: 'Guitar' },
+          { name: 'Duff', role: 'Bass' },
+          { name: 'Adler', role: 'Drums' }
         ]
       });
 
       gnr.save(function(error) {
         assert.ifError(error);
-        gnr.members.pull({name: 'Slash', role: 'Guitar'});
+        gnr.members.pull({ name: 'Slash', role: 'Guitar' });
         gnr.save(function(error) {
           assert.ifError(error);
           assert.equal(gnr.members.length, 4);
@@ -795,12 +795,12 @@ describe('types array', function() {
     });
 
     it('properly works with undefined', function(done) {
-      const catschema = new Schema({ name: String, colors: [{hex: String}] });
+      const catschema = new Schema({ name: String, colors: [{ hex: String }] });
       const Cat = db.model('Test', catschema);
 
-      const cat = new Cat({name: 'peanut', colors: [
-        {hex: '#FFF'}, {hex: '#000'}, null
-      ]});
+      const cat = new Cat({ name: 'peanut', colors: [
+        { hex: '#FFF' }, { hex: '#000' }, null
+      ] });
 
       cat.save(function(err) {
         assert.ifError(err);
@@ -827,9 +827,9 @@ describe('types array', function() {
 
   describe('$pop()', function() {
     it('works', function(done) {
-      const painting = new Schema({colors: []});
+      const painting = new Schema({ colors: [] });
       const Painting = db.model('Test', painting);
-      const p = new Painting({colors: ['blue', 'green', 'yellow']});
+      const p = new Painting({ colors: ['blue', 'green', 'yellow'] });
       p.save(function(err) {
         assert.ifError(err);
 
@@ -867,7 +867,7 @@ describe('types array', function() {
 
   describe('addToSet()', function() {
     it('works', function(done) {
-      const e = new Schema({name: String, arr: []});
+      const e = new Schema({ name: String, arr: [] });
       const schema = new Schema({
         num: [Number],
         str: [String],
@@ -881,7 +881,7 @@ describe('types array', function() {
 
       m.num.push(1, 2, 3);
       m.str.push('one', 'two', 'tres');
-      m.doc.push({name: 'Dubstep', arr: [1]}, {name: 'Polka', arr: [{x: 3}]});
+      m.doc.push({ name: 'Dubstep', arr: [1] }, { name: 'Polka', arr: [{ x: 3 }] });
 
       const d1 = new Date;
       const d2 = new Date(+d1 + 60000);
@@ -908,7 +908,7 @@ describe('types array', function() {
       assert.equal(m.id.length, 3);
       m.doc.addToSet(m.doc[0]);
       assert.equal(m.doc.length, 2);
-      m.doc.addToSet({name: 'Waltz', arr: [1]}, m.doc[0]);
+      m.doc.addToSet({ name: 'Waltz', arr: [1] }, m.doc[0]);
       assert.equal(m.doc.length, 3);
       assert.equal(m.date.length, 2);
       m.date.addToSet(d1);
@@ -967,7 +967,7 @@ describe('types array', function() {
           m.date.addToSet(d1, d3, d4);
           assert.equal(m.date.length, 4);
 
-          m.doc.addToSet(m.doc[0], {name: '8bit'});
+          m.doc.addToSet(m.doc[0], { name: '8bit' });
           assert.equal(m.doc.length, 4);
 
           m.save(function(err) {
@@ -1029,7 +1029,7 @@ describe('types array', function() {
               m.date.addToSet(d5, d6);
               assert.equal(m.date.length, 6);
 
-              m.doc.addToSet(m.doc[1], {name: 'BigBeat'}, {name: 'Funk'});
+              m.doc.addToSet(m.doc[1], { name: 'BigBeat' }, { name: 'Funk' });
               assert.equal(m.doc.length, 6);
 
               m.save(function(err) {
@@ -1103,7 +1103,7 @@ describe('types array', function() {
     });
 
     it('handles sub-documents that do not have an _id gh-1973', function(done) {
-      const e = new Schema({name: String, arr: []}, {_id: false});
+      const e = new Schema({ name: String, arr: [] }, { _id: false });
       const schema = new Schema({
         doc: [e]
       });
@@ -1111,12 +1111,12 @@ describe('types array', function() {
       const M = db.model('Test', schema);
       const m = new M;
 
-      m.doc.addToSet({name: 'Rap'});
+      m.doc.addToSet({ name: 'Rap' });
       m.save(function(error, m) {
         assert.ifError(error);
         assert.equal(m.doc.length, 1);
         assert.equal(m.doc[0].name, 'Rap');
-        m.doc.addToSet({name: 'House'});
+        m.doc.addToSet({ name: 'House' });
         assert.equal(m.doc.length, 2);
         m.save(function(error, m) {
           assert.ifError(error);
@@ -1139,7 +1139,7 @@ describe('types array', function() {
           lowercase: true
         }]
       }));
-      const m = new ST({arr: ['ONE', 'TWO']});
+      const m = new ST({ arr: ['ONE', 'TWO'] });
       m.save(function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
@@ -1225,7 +1225,7 @@ describe('types array', function() {
       const U = db.model('User', UserSchema);
       const ID = mongoose.Types.ObjectId;
 
-      const u = new U({name: 'banana', pets: [new ID]});
+      const u = new U({ name: 'banana', pets: [new ID] });
       assert.equal(u.pets.length, 1);
       u.pets.nonAtomicPush(new ID);
       assert.equal(u.pets.length, 2);
@@ -1259,8 +1259,8 @@ describe('types array', function() {
 
   describe('sort()', function() {
     it('order should be saved', function(done) {
-      const M = db.model('Test', new Schema({x: [Number]}));
-      const m = new M({x: [1, 4, 3, 2]});
+      const M = db.model('Test', new Schema({ x: [Number] }));
+      const m = new M({ x: [1, 4, 3, 2] });
       m.save(function(err) {
         assert.ifError(err);
         M.findById(m, function(err, m) {
@@ -1318,9 +1318,9 @@ describe('types array', function() {
     }
 
     it('works combined with other ops', function(done) {
-      const N = db.model('Test', Schema({arr: [Number]}));
+      const N = db.model('Test', Schema({ arr: [Number] }));
 
-      const m = new N({arr: [3, 4, 5, 6]});
+      const m = new N({ arr: [3, 4, 5, 6] });
       save(m, function(err, doc) {
         assert.ifError(err);
 
@@ -1366,9 +1366,9 @@ describe('types array', function() {
     });
 
     it('works with numbers', function(done) {
-      const N = db.model('Test', Schema({arr: [Number]}));
+      const N = db.model('Test', Schema({ arr: [Number] }));
 
-      const m = new N({arr: [3, 4, 5, 6]});
+      const m = new N({ arr: [3, 4, 5, 6] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 4);
@@ -1414,9 +1414,9 @@ describe('types array', function() {
     });
 
     it('works with strings', function(done) {
-      const S = db.model('Test', Schema({arr: [String]}));
+      const S = db.model('Test', Schema({ arr: [String] }));
 
-      const m = new S({arr: [3, 4, 5, 6]});
+      const m = new S({ arr: [3, 4, 5, 6] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, '4');
@@ -1462,9 +1462,9 @@ describe('types array', function() {
     });
 
     it('works with buffers', function(done) {
-      const B = db.model('Test', Schema({arr: [Buffer]}));
+      const B = db.model('Test', Schema({ arr: [Buffer] }));
 
-      const m = new B({arr: [[0], Buffer.alloc(1)]});
+      const m = new B({ arr: [[0], Buffer.alloc(1)] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
@@ -1493,9 +1493,9 @@ describe('types array', function() {
     });
 
     it('works with mixed', function(done) {
-      const M = db.model('Test', Schema({arr: []}));
+      const M = db.model('Test', Schema({ arr: [] }));
 
-      const m = new M({arr: [3, {x: 1}, 'yes', [5]]});
+      const m = new M({ arr: [3, { x: 1 }, 'yes', [5]] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 4);
@@ -1550,16 +1550,16 @@ describe('types array', function() {
     });
 
     it('works with sub-docs', function(done) {
-      const D = db.model('Test', Schema({arr: [{name: String}]}));
+      const D = db.model('Test', Schema({ arr: [{ name: String }] }));
 
-      const m = new D({arr: [{name: 'aaron'}, {name: 'moombahton '}]});
+      const m = new D({ arr: [{ name: 'aaron' }, { name: 'moombahton ' }] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
-        doc.arr.set(0, {name: 'vdrums'});
+        doc.arr.set(0, { name: 'vdrums' });
         assert.equal(doc.arr.length, 2);
         assert.equal(doc.arr[0].name, 'vdrums');
-        doc.arr.set(doc.arr.length, {name: 'Restrepo'});
+        doc.arr.set(doc.arr.length, { name: 'Restrepo' });
         assert.equal(doc.arr.length, 3);
         assert.equal(doc.arr[2].name, 'Restrepo');
 
@@ -1572,7 +1572,7 @@ describe('types array', function() {
           assert.equal(doc.arr[1].name, 'moombahton ');
           assert.equal(doc.arr[2].name, 'Restrepo');
 
-          doc.arr.set(10, {name: 'temple of doom'});
+          doc.arr.set(10, { name: 'temple of doom' });
           assert.equal(doc.arr.length, 11);
           assert.equal(doc.arr[10].name, 'temple of doom');
           assert.equal(doc.arr[9], null);
@@ -1590,7 +1590,7 @@ describe('types array', function() {
             assert.equal(doc.arr[10].name, 'temple of doom');
 
             doc.arr.remove(doc.arr[0]);
-            doc.arr.set(7, {name: 7});
+            doc.arr.set(7, { name: 7 });
             assert.strictEqual('7', doc.arr[7].name);
             assert.equal(doc.arr.length, 10);
 
@@ -1621,7 +1621,7 @@ describe('types array', function() {
         }]
       }));
 
-      const m = new ST({arr: ['ONE', 'TWO']});
+      const m = new ST({ arr: ['ONE', 'TWO'] });
       save(m, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.arr.length, 2);
@@ -1675,14 +1675,14 @@ describe('types array', function() {
   describe('setting a doc array', function() {
     it('should adjust path positions', function(done) {
       const D = db.model('Test', new Schema({
-        em1: [new Schema({name: String})]
+        em1: [new Schema({ name: String })]
       }));
 
       const d = new D({
         em1: [
-          {name: 'pos0'},
-          {name: 'pos1'},
-          {name: 'pos2'}
+          { name: 'pos0' },
+          { name: 'pos1' },
+          { name: 'pos2' }
         ]
       });
 
@@ -1720,12 +1720,12 @@ describe('types array', function() {
           role: String,
           roles: [String]
         },
-        em: [new Schema({name: String})]
+        em: [new Schema({ name: String })]
       }));
 
       const d = new D({
-        account: {role: 'teacher', roles: ['teacher', 'admin']},
-        em: [{name: 'bob'}]
+        account: { role: 'teacher', roles: ['teacher', 'admin'] },
+        em: [{ name: 'bob' }]
       });
 
       d.save(function(err) {
@@ -1736,7 +1736,7 @@ describe('types array', function() {
           d.account.role = 'president';
           d.account.roles = ['president', 'janitor'];
           d.em[0].name = 'memorable';
-          d.em = [{name: 'frida'}];
+          d.em = [{ name: 'frida' }];
 
           d.save(function(err) {
             assert.ifError(err);
@@ -1758,16 +1758,16 @@ describe('types array', function() {
 
   describe('of number', function() {
     it('allows nulls', function(done) {
-      const schema = new Schema({x: [Number]}, {collection: 'nullsareallowed' + random()});
+      const schema = new Schema({ x: [Number] }, { collection: 'nullsareallowed' + random() });
       const M = db.model('Test', schema);
       let m;
 
-      m = new M({x: [1, null, 3]});
+      m = new M({ x: [1, null, 3] });
       m.save(function(err) {
         assert.ifError(err);
 
         // undefined is not allowed
-        m = new M({x: [1, undefined, 3]});
+        m = new M({ x: [1, undefined, 3] });
         m.save(function(err) {
           assert.ok(err);
           done();
@@ -1778,9 +1778,9 @@ describe('types array', function() {
 
   describe('bug fixes', function() {
     it('modifying subdoc props and manipulating the array works (gh-842)', function(done) {
-      const schema = new Schema({em: [new Schema({username: String})]});
+      const schema = new Schema({ em: [new Schema({ username: String })] });
       const M = db.model('Test', schema);
-      const m = new M({em: [{username: 'Arrietty'}]});
+      const m = new M({ em: [{ username: 'Arrietty' }] });
 
       m.save(function(err) {
         assert.ifError(err);
@@ -1789,7 +1789,7 @@ describe('types array', function() {
           assert.equal(m.em[0].username, 'Arrietty');
 
           m.em[0].username = 'Shawn';
-          m.em.push({username: 'Homily'});
+          m.em.push({ username: 'Homily' });
           m.save(function(err) {
             assert.ifError(err);
 
@@ -1818,15 +1818,15 @@ describe('types array', function() {
     });
 
     it('pushing top level arrays and subarrays works (gh-1073)', function(done) {
-      const schema = new Schema({em: [new Schema({sub: [String]})]});
+      const schema = new Schema({ em: [new Schema({ sub: [String] })] });
       const M = db.model('Test', schema);
-      const m = new M({em: [{sub: []}]});
+      const m = new M({ em: [{ sub: [] }] });
       m.save(function() {
         M.findById(m, function(err, m) {
           assert.ifError(err);
 
           m.em[m.em.length - 1].sub.push('a');
-          m.em.push({sub: []});
+          m.em.push({ sub: [] });
 
           assert.equal(m.em.length, 2);
           assert.equal(m.em[0].sub.length, 1);
@@ -1883,7 +1883,7 @@ describe('types array', function() {
           threw2 = false;
 
       try {
-        arr.num1.push({x: 1});
+        arr.num1.push({ x: 1 });
         arr.num1.push(9);
         arr.num1.push('woah');
       } catch (err) {
@@ -1893,7 +1893,7 @@ describe('types array', function() {
       assert.equal(threw1, false);
 
       try {
-        arr.num2.push({x: 1});
+        arr.num2.push({ x: 1 });
         arr.num2.push(9);
         arr.num2.push('woah');
       } catch (err) {
@@ -1911,10 +1911,10 @@ describe('types array', function() {
     before(function(done) {
       const schema = new Schema({
         numbers: ['number'],
-        numberIds: [{_id: 'number', name: 'string'}],
-        stringIds: [{_id: 'string', name: 'string'}],
-        bufferIds: [{_id: 'buffer', name: 'string'}],
-        oidIds: [{name: 'string'}]
+        numberIds: [{ _id: 'number', name: 'string' }],
+        stringIds: [{ _id: 'string', name: 'string' }],
+        bufferIds: [{ _id: 'buffer', name: 'string' }],
+        oidIds: [{ name: 'string' }]
       });
 
       B = db.model('BlogPost', schema);
@@ -1959,12 +1959,12 @@ describe('types array', function() {
     describe('with subdocs', function() {
       function docs(arr) {
         return arr.map(function(val) {
-          return {_id: val};
+          return { _id: val };
         });
       }
 
       it('supports passing strings', function(done) {
-        const post = new B({stringIds: docs('a b c d'.split(' '))});
+        const post = new B({ stringIds: docs('a b c d'.split(' ')) });
         post.save(function(err) {
           assert.ifError(err);
           B.findById(post, function(err, post) {
@@ -1983,7 +1983,7 @@ describe('types array', function() {
         });
       });
       it('supports passing numbers', function(done) {
-        const post = new B({numberIds: docs([1, 2, 3, 4])});
+        const post = new B({ numberIds: docs([1, 2, 3, 4]) });
         post.save(function(err) {
           assert.ifError(err);
           B.findById(post, function(err, post) {
@@ -2007,7 +2007,7 @@ describe('types array', function() {
         const a = new OID;
         const b = new OID;
         const c = new OID;
-        const post = new B({oidIds: docs([a, b, c])});
+        const post = new B({ oidIds: docs([a, b, c]) });
         post.save(function(err) {
           assert.ifError(err);
           B.findById(post, function(err, post) {
@@ -2027,7 +2027,7 @@ describe('types array', function() {
         });
       });
       it('supports passing buffers', function(done) {
-        const post = new B({bufferIds: docs(['a', 'b', 'c', 'd'])});
+        const post = new B({ bufferIds: docs(['a', 'b', 'c', 'd']) });
         post.save(function(err) {
           assert.ifError(err);
           B.findById(post, function(err, post) {
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index a888af52c33..b391ae6e8d6 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -36,14 +36,14 @@ describe('types.buffer', function() {
 
     subBuf = new Schema({
       name: String,
-      buf: {type: Buffer, validate: [valid, 'valid failed'], required: true}
+      buf: { type: Buffer, validate: [valid, 'valid failed'], required: true }
     });
 
     UserBuffer = new Schema({
       name: String,
       serial: Buffer,
       array: [Buffer],
-      required: {type: Buffer, required: true, index: true},
+      required: { type: Buffer, required: true, index: true },
       sub: [subBuf]
     });
   });
@@ -82,17 +82,17 @@ describe('types.buffer', function() {
       t.validate(function(err) {
         assert.ok(err.message.indexOf('UserBuffer validation failed') === 0, err.message);
         assert.equal(err.errors.required.kind, 'required');
-        t.required = {x: [20]};
+        t.required = { x: [20] };
         t.save(function(err) {
           assert.ok(err);
           assert.equal(err.name, 'ValidationError');
           assert.equal(err.errors.required.name, 'CastError');
           assert.equal(err.errors.required.kind, 'Buffer');
           assert.equal(err.errors.required.message, 'Cast to Buffer failed for value "{ x: [ 20 ] }" at path "required"');
-          assert.deepEqual(err.errors.required.value, {x: [20]});
+          assert.deepEqual(err.errors.required.value, { x: [20] });
           t.required = Buffer.from('hello');
 
-          t.sub.push({name: 'Friday Friday'});
+          t.sub.push({ name: 'Friday Friday' });
           t.save(function(err) {
             assert.ok(err.message.indexOf('UserBuffer validation failed') === 0, err.message);
             assert.equal(err.errors['sub.0.buf'].kind, 'required');
@@ -374,7 +374,7 @@ describe('types.buffer', function() {
 
   it('can be set to null', function(done) {
     const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
-    const user = new User({array: [null], required: Buffer.alloc(1)});
+    const user = new User({ array: [null], required: Buffer.alloc(1) });
     user.save(function(err, doc) {
       assert.ifError(err);
       User.findById(doc, function(err, doc) {
@@ -388,10 +388,10 @@ describe('types.buffer', function() {
 
   it('can be updated to null', function(done) {
     const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
-    const user = new User({array: [null], required: Buffer.alloc(1), serial: Buffer.alloc(1)});
+    const user = new User({ array: [null], required: Buffer.alloc(1), serial: Buffer.alloc(1) });
     user.save(function(err, doc) {
       assert.ifError(err);
-      User.findOneAndUpdate({_id: doc.id}, {serial: null}, {new: true}, function(err, doc) {
+      User.findOneAndUpdate({ _id: doc.id }, { serial: null }, { new: true }, function(err, doc) {
         assert.ifError(err);
         assert.equal(doc.serial, null);
         done();
@@ -413,26 +413,26 @@ describe('types.buffer', function() {
     let bufferSchema, B;
 
     before(function(done) {
-      bufferSchema = new Schema({buf: Buffer});
+      bufferSchema = new Schema({ buf: Buffer });
       B = db.model('1571', bufferSchema);
       done();
     });
 
     it('default value', function(done) {
-      const b = new B({buf: Buffer.from('hi')});
+      const b = new B({ buf: Buffer.from('hi') });
       assert.strictEqual(0, b.buf._subtype);
       done();
     });
 
     it('method works', function(done) {
-      const b = new B({buf: Buffer.from('hi')});
+      const b = new B({ buf: Buffer.from('hi') });
       b.buf.subtype(128);
       assert.strictEqual(128, b.buf._subtype);
       done();
     });
 
     it('is stored', function(done) {
-      const b = new B({buf: Buffer.from('hi')});
+      const b = new B({ buf: Buffer.from('hi') });
       b.buf.subtype(128);
       b.save(function(err) {
         if (err) {
@@ -451,7 +451,7 @@ describe('types.buffer', function() {
     });
 
     it('changes are retained', function(done) {
-      const b = new B({buf: Buffer.from('hi')});
+      const b = new B({ buf: Buffer.from('hi') });
       b.buf.subtype(128);
       b.save(function(err) {
         if (err) {
@@ -484,49 +484,49 @@ describe('types.buffer', function() {
     });
 
     it('cast from number (gh-3764)', function(done) {
-      const schema = new Schema({buf: Buffer});
+      const schema = new Schema({ buf: Buffer });
       const MyModel = mongoose.model('gh3764', schema);
 
-      const doc = new MyModel({buf: 9001});
+      const doc = new MyModel({ buf: 9001 });
       assert.equal(doc.buf.length, 1);
       done();
     });
 
     it('cast from string', function(done) {
-      const schema = new Schema({buf: Buffer});
+      const schema = new Schema({ buf: Buffer });
       const MyModel = mongoose.model('bufferFromString', schema);
 
-      const doc = new MyModel({buf: 'hi'});
+      const doc = new MyModel({ buf: 'hi' });
       assert.ok(doc.buf instanceof Buffer);
       assert.equal(doc.buf.toString('utf8'), 'hi');
       done();
     });
 
     it('cast from array', function(done) {
-      const schema = new Schema({buf: Buffer});
+      const schema = new Schema({ buf: Buffer });
       const MyModel = mongoose.model('bufferFromArray', schema);
 
-      const doc = new MyModel({buf: [195, 188, 98, 101, 114]});
+      const doc = new MyModel({ buf: [195, 188, 98, 101, 114] });
       assert.ok(doc.buf instanceof Buffer);
       assert.equal(doc.buf.toString('utf8'), 'über');
       done();
     });
 
     it('cast from Binary', function(done) {
-      const schema = new Schema({buf: Buffer});
+      const schema = new Schema({ buf: Buffer });
       const MyModel = mongoose.model('bufferFromBinary', schema);
 
-      const doc = new MyModel({buf: new MongooseBuffer.Binary([228, 189, 160, 229, 165, 189], 0)});
+      const doc = new MyModel({ buf: new MongooseBuffer.Binary([228, 189, 160, 229, 165, 189], 0) });
       assert.ok(doc.buf instanceof Buffer);
       assert.equal(doc.buf.toString('utf8'), '你好');
       done();
     });
 
     it('cast from json (gh-6863)', function(done) {
-      const schema = new Schema({buf: Buffer});
+      const schema = new Schema({ buf: Buffer });
       const MyModel = mongoose.model('gh6863', schema);
 
-      const doc = new MyModel({buf: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51]}});
+      const doc = new MyModel({ buf: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] } });
       assert.ok(doc.buf instanceof Buffer);
       assert.equal(doc.buf.toString('utf8'), 'gh-6863');
       done();
diff --git a/test/types.document.test.js b/test/types.document.test.js
index 57408268740..cadd7b7822f 100644
--- a/test/types.document.test.js
+++ b/test/types.document.test.js
@@ -52,13 +52,13 @@ describe('types.document', function() {
     }
 
     Subdocument.prototype.$__setSchema(new Schema({
-      test: {type: String, required: true},
-      work: {type: String, validate: /^good/}
+      test: { type: String, required: true },
+      work: { type: String, validate: /^good/ }
     }));
 
     RatingSchema = new Schema({
       stars: Number,
-      description: {source: {url: String, time: Date}}
+      description: { source: { url: String, time: Date } }
     });
 
     MovieSchema = new Schema({
@@ -89,7 +89,7 @@ describe('types.document', function() {
 
   it('objects can be passed to #set', function(done) {
     const a = new Subdocument();
-    a.set({test: 'paradiddle', work: 'good flam'});
+    a.set({ test: 'paradiddle', work: 'good flam' });
     assert.equal(a.test, 'paradiddle');
     assert.equal(a.work, 'good flam');
     done();
@@ -97,7 +97,7 @@ describe('types.document', function() {
 
   it('Subdocuments can be passed to #set', function(done) {
     const a = new Subdocument();
-    a.set({test: 'paradiddle', work: 'good flam'});
+    a.set({ test: 'paradiddle', work: 'good flam' });
     assert.equal(a.test, 'paradiddle');
     assert.equal(a.work, 'good flam');
     const b = new Subdocument();
@@ -119,7 +119,7 @@ describe('types.document', function() {
 
     const m2 = new Movie;
     delete m2._doc._id;
-    m2.init({_id: new mongoose.Types.ObjectId});
+    m2.init({ _id: new mongoose.Types.ObjectId });
     assert.equal(m2.id, m2.$__._id);
     assert.strictEqual(true, m.$__._id !== m2.$__._id);
     assert.strictEqual(true, m.id !== m2.id);
@@ -130,17 +130,17 @@ describe('types.document', function() {
   it('Subdocument#remove (gh-531)', function(done) {
     const Movie = db.model('Movie');
 
-    const super8 = new Movie({title: 'Super 8'});
+    const super8 = new Movie({ title: 'Super 8' });
 
     const id1 = '4e3d5fc7da5d7eb635063c96';
     const id2 = '4e3d5fc7da5d7eb635063c97';
     const id3 = '4e3d5fc7da5d7eb635063c98';
     const id4 = '4e3d5fc7da5d7eb635063c99';
 
-    super8.ratings.push({stars: 9, _id: id1});
-    super8.ratings.push({stars: 8, _id: id2});
-    super8.ratings.push({stars: 7, _id: id3});
-    super8.ratings.push({stars: 6, _id: id4});
+    super8.ratings.push({ stars: 9, _id: id1 });
+    super8.ratings.push({ stars: 8, _id: id2 });
+    super8.ratings.push({ stars: 7, _id: id3 });
+    super8.ratings.push({ stars: 6, _id: id4 });
 
     super8.save(function(err) {
       assert.ifError(err);
@@ -219,7 +219,7 @@ describe('types.document', function() {
           assert.ifError(err);
 
           assert.ok(movie.ratings[0].description.source.time instanceof Date);
-          movie.ratings[0].description.source = {url: 'http://www.lifeofpimovie.com/'};
+          movie.ratings[0].description.source = { url: 'http://www.lifeofpimovie.com/' };
 
           movie.save(function(err) {
             assert.ifError(err);
@@ -233,7 +233,7 @@ describe('types.document', function() {
               assert.equal(undefined, movie.ratings[0].description.source.time);
 
               const newDate = new Date;
-              movie.ratings[0].set('description.source.time', newDate, {merge: true});
+              movie.ratings[0].set('description.source.time', newDate, { merge: true });
               movie.save(function(err) {
                 assert.ifError(err);
 
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index e51d4d95492..dd9f0d7ca73 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -38,7 +38,7 @@ function TestDoc(schema) {
    */
 
   const SubSchema = new Schema({
-    title: {type: String}
+    title: { type: String }
   });
 
   Subdocument.prototype.$__setSchema(schema || SubSchema);
@@ -87,8 +87,8 @@ describe('types.documentarray', function() {
 
     // test with custom string _id
     let Custom = new Schema({
-      title: {type: String},
-      _id: {type: String, required: true}
+      title: { type: String },
+      _id: { type: String, required: true }
     });
 
     Subdocument = TestDoc(Custom);
@@ -104,8 +104,8 @@ describe('types.documentarray', function() {
 
     // test with custom number _id
     const CustNumber = new Schema({
-      title: {type: String},
-      _id: {type: Number, required: true}
+      title: { type: String },
+      _id: { type: Number, required: true }
     });
 
     Subdocument = TestDoc(CustNumber);
@@ -121,28 +121,28 @@ describe('types.documentarray', function() {
 
     // test with object as _id
     Custom = new Schema({
-      title: {type: String},
-      _id: {one: {type: String}, two: {type: String}}
+      title: { type: String },
+      _id: { one: { type: String }, two: { type: String } }
     });
 
     Subdocument = TestDoc(Custom);
 
     sub1 = new Subdocument();
-    sub1._id = {one: 'rolling', two: 'rock'};
+    sub1._id = { one: 'rolling', two: 'rock' };
     sub1.title = 'to be a rock and not to roll';
 
     sub2 = new Subdocument();
-    sub2._id = {one: 'rock', two: 'roll'};
+    sub2._id = { one: 'rock', two: 'roll' };
     sub2.title = 'rock-n-roll';
 
     a = new MongooseDocumentArray([sub1, sub2]);
-    assert.notEqual(a.id({one: 'rolling', two: 'rock'}).title, 'rock-n-roll');
-    assert.equal(a.id({one: 'rock', two: 'roll'}).title, 'rock-n-roll');
+    assert.notEqual(a.id({ one: 'rolling', two: 'rock' }).title, 'rock-n-roll');
+    assert.equal(a.id({ one: 'rock', two: 'roll' }).title, 'rock-n-roll');
 
     // test with no _id
     let NoId = new Schema({
-      title: {type: String}
-    }, {noId: true});
+      title: { type: String }
+    }, { noId: true });
 
     Subdocument = TestDoc(NoId);
 
@@ -160,8 +160,8 @@ describe('types.documentarray', function() {
 
     // test the _id option, noId is deprecated
     NoId = new Schema({
-      title: {type: String}
-    }, {_id: false});
+      title: { type: String }
+    }, { _id: false });
 
     Subdocument = TestDoc(NoId);
 
@@ -182,10 +182,10 @@ describe('types.documentarray', function() {
 
     // test when _id is a populated document
     Custom = new Schema({
-      title: {type: String}
+      title: { type: String }
     });
 
-    const Custom1 = new Schema({}, {id: false});
+    const Custom1 = new Schema({}, { id: false });
 
     Subdocument = TestDoc(Custom);
     const Subdocument1 = TestDoc(Custom1);
@@ -232,7 +232,7 @@ describe('types.documentarray', function() {
     });
     it('passes options to its documents (gh-1415) (gh-4455)', function(done) {
       const subSchema = new Schema({
-        title: {type: String}
+        title: { type: String }
       });
 
       subSchema.set('toObject', {
@@ -245,17 +245,17 @@ describe('types.documentarray', function() {
       });
 
       const db = mongoose.createConnection();
-      let M = db.model('gh-1415', {docs: [subSchema]});
+      let M = db.model('gh-1415', { docs: [subSchema] });
       let m = new M;
-      m.docs.push({docs: [{title: 'hello'}]});
+      m.docs.push({ docs: [{ title: 'hello' }] });
       let delta = m.$__delta()[1];
       assert.equal(delta.$push.docs.$each[0].changed, undefined);
 
-      M = db.model('gh-1415-1', new Schema({docs: [subSchema]}, {
+      M = db.model('gh-1415-1', new Schema({ docs: [subSchema] }, {
         usePushEach: true
       }));
       m = new M;
-      m.docs.push({docs: [{title: 'hello'}]});
+      m.docs.push({ docs: [{ title: 'hello' }] });
       delta = m.$__delta()[1];
       assert.equal(delta.$push.docs.$each[0].changed, undefined);
 
@@ -305,11 +305,11 @@ describe('types.documentarray', function() {
       const a = new MongooseDocumentArray([]);
       assert.equal(typeof a.create, 'function');
 
-      const schema = new Schema({docs: [new Schema({name: 'string'})]});
+      const schema = new Schema({ docs: [new Schema({ name: 'string' })] });
       const T = mongoose.model('embeddedDocument#create_test', schema, 'asdfasdfa' + random());
       const t = new T;
       assert.equal(typeof t.docs.create, 'function');
-      const subdoc = t.docs.create({name: 100});
+      const subdoc = t.docs.create({ name: 100 });
       assert.ok(subdoc._id);
       assert.equal(subdoc.name, '100');
       assert.ok(subdoc instanceof EmbeddedDocument);
@@ -319,19 +319,19 @@ describe('types.documentarray', function() {
 
   describe('push()', function() {
     it('does not re-cast instances of its embedded doc', function(done) {
-      const child = new Schema({name: String, date: Date});
+      const child = new Schema({ name: String, date: Date });
       child.pre('save', function(next) {
         this.date = new Date;
         next();
       });
-      const schema = new Schema({children: [child]});
+      const schema = new Schema({ children: [child] });
       const M = db.model('embeddedDocArray-push-re-cast', schema, 'edarecast-' + random());
       const m = new M;
       m.save(function(err) {
         assert.ifError(err);
         M.findById(m._id, function(err, doc) {
           assert.ifError(err);
-          const c = doc.children.create({name: 'first'});
+          const c = doc.children.create({ name: 'first' });
           assert.equal(c.date, undefined);
           doc.children.push(c);
           assert.equal(c.date, undefined);
@@ -361,9 +361,9 @@ describe('types.documentarray', function() {
 
     it('corrects #ownerDocument() and index if value was created with array.create() (gh-1385)', function(done) {
       const mg = new mongoose.Mongoose;
-      const M = mg.model('1385', {docs: [{name: String}]});
+      const M = mg.model('1385', { docs: [{ name: String }] });
       const m = new M;
-      const doc = m.docs.create({name: 'test 1385'});
+      const doc = m.docs.create({ name: 'test 1385' });
       assert.equal(String(doc.ownerDocument()._id), String(m._id));
       m.docs.push(doc);
       assert.equal(doc.ownerDocument()._id, String(m._id));
@@ -373,10 +373,10 @@ describe('types.documentarray', function() {
 
     it('corrects #ownerDocument() if value was created with array.create() and set() (gh-7504)', function(done) {
       const M = db.model('gh7504', {
-        docs: [{name: { type: String, validate: () => false } }]
+        docs: [{ name: { type: String, validate: () => false } }]
       });
       const m = new M({});
-      const doc = m.docs.create({name: 'test'});
+      const doc = m.docs.create({ name: 'test' });
       m.set('docs', [doc]);
       assert.equal(doc.ownerDocument()._id.toString(), String(m._id));
       assert.strictEqual(doc.__index, 0);
@@ -398,7 +398,7 @@ describe('types.documentarray', function() {
 
       const p = new Parent({
         name: 'Eddard Stark',
-        children: [{ name: 'Arya Stark', gender: 'F'}]
+        children: [{ name: 'Arya Stark', gender: 'F' }]
       });
 
       p.children.push({ name: 'Sansa Stark' });
@@ -427,10 +427,10 @@ describe('types.documentarray', function() {
 
     const Post = db.model('docarray-BlogPost', BlogPost, collection);
 
-    const p = new Post({title: 'comment nesting'});
-    const c1 = p.comments.create({title: 'c1'});
-    const c2 = c1.comments.create({title: 'c2'});
-    const c3 = c2.comments.create({title: 'c3'});
+    const p = new Post({ title: 'comment nesting' });
+    const c1 = p.comments.create({ title: 'c1' });
+    const c2 = c1.comments.create({ title: 'c2' });
+    const c3 = c2.comments.create({ title: 'c3' });
 
     p.comments.push(c1);
     c1.comments.push(c2);
@@ -442,7 +442,7 @@ describe('types.documentarray', function() {
       Post.findById(p._id, function(err, p) {
         assert.ifError(err);
 
-        p.comments[0].comments[0].comments[0].comments.push({title: 'c4'});
+        p.comments[0].comments[0].comments[0].comments.push({ title: 'c4' });
         p.save(function(err) {
           assert.ifError(err);
 
@@ -461,7 +461,7 @@ describe('types.documentarray', function() {
       const calls = [];
       const schema = new Schema({
         docs: {
-          type: [{name: 'string'}],
+          type: [{ name: 'string' }],
           required: function() {
             calls.push(this);
             return true;
@@ -471,8 +471,8 @@ describe('types.documentarray', function() {
 
       const T = mongoose.model('TopLevelRequired', schema);
       const t = new T({});
-      t.docs.push({name: 'test1'});
-      t.docs.push({name: 'test2'});
+      t.docs.push({ name: 'test1' });
+      t.docs.push({ name: 'test2' });
 
       t.validateSync();
       assert.equal(calls.length, 1);
@@ -494,7 +494,7 @@ describe('types.documentarray', function() {
       const T = mongoose.model('DocArrayNestedRequired', schema);
       const t = new T({});
       t.docs.push(null);
-      t.docs.push({name: 'test2'});
+      t.docs.push({ name: 'test2' });
 
       const err = t.validateSync();
       assert.equal(calls.length, 2);
@@ -506,7 +506,7 @@ describe('types.documentarray', function() {
 
   describe('invalidate()', function() {
     it('works', function(done) {
-      const schema = new Schema({docs: [{name: 'string'}]});
+      const schema = new Schema({ docs: [{ name: 'string' }] });
       schema.pre('validate', function(next) {
         const subdoc = this.docs[this.docs.length - 1];
         subdoc.invalidate('name', 'boo boo', '%');
@@ -514,9 +514,9 @@ describe('types.documentarray', function() {
       });
       const T = mongoose.model('embeddedDocument#invalidate_test', schema, 'asdfasdfa' + random());
       const t = new T;
-      t.docs.push({name: 100});
+      t.docs.push({ name: 100 });
 
-      const subdoc = t.docs.create({name: 'yep'});
+      const subdoc = t.docs.create({ name: 'yep' });
       assert.throws(function() {
         // has no parent array
         subdoc.invalidate('name', 'junk', 47);
@@ -533,12 +533,12 @@ describe('types.documentarray', function() {
     });
 
     it('handles validation failures', function(done) {
-      const nested = new Schema({v: {type: Number, max: 30}});
+      const nested = new Schema({ v: { type: Number, max: 30 } });
       const schema = new Schema({
         docs: [nested]
-      }, {collection: 'embedded-invalidate-' + random()});
+      }, { collection: 'embedded-invalidate-' + random() });
       const M = db.model('embedded-invalidate', schema);
-      const m = new M({docs: [{v: 900}]});
+      const m = new M({ docs: [{ v: 900 }] });
       m.save(function(err) {
         assert.equal(err.errors['docs.0.v'].value, 900);
         done();
@@ -567,7 +567,7 @@ describe('types.documentarray', function() {
       });
       const M = db.model('gh8317', schema);
 
-      const doc = M.hydrate({ docs: [{ v: 1 }, { v: 2 }]});
+      const doc = M.hydrate({ docs: [{ v: 1 }, { v: 2 }] });
       let arr = doc.docs;
       arr = arr.slice();
       arr.splice(0, 1);
@@ -577,7 +577,7 @@ describe('types.documentarray', function() {
     });
 
     it('map() works', function() {
-      const personSchema = new Schema({ friends: [{ name: { type: String } }]});
+      const personSchema = new Schema({ friends: [{ name: { type: String } }] });
       const Person = mongoose.model('gh8317-map', personSchema);
 
       const person = new Person({ friends: [{ name: 'Hafez' }] });
diff --git a/test/types.embeddeddocumentdeclarative.test.js b/test/types.embeddeddocumentdeclarative.test.js
index 6b6cfdea93a..42e3e9773ca 100644
--- a/test/types.embeddeddocumentdeclarative.test.js
+++ b/test/types.embeddeddocumentdeclarative.test.js
@@ -48,7 +48,7 @@ describe('types.embeddeddocumentdeclarative', function() {
       });
     });
     describe('with the optional subschema behavior (typePojoToMixed=false)', function() {
-      const ParentSchema = new mongoose.Schema(ParentSchemaDef, {typePojoToMixed: false});
+      const ParentSchema = new mongoose.Schema(ParentSchemaDef, { typePojoToMixed: false });
       it('interprets the POJO as a subschema (gh-7494)', function(done) {
         assert.equal(ParentSchema.paths.child.instance, 'Embedded');
         assert.strictEqual(ParentSchema.paths.child['$isSingleNested'], true);
@@ -112,7 +112,7 @@ describe('types.embeddeddocumentdeclarative', function() {
       }
     };
     const ParentSchemaNotMixed = new Schema(ParentSchemaDef);
-    const ParentSchemaNotSubdoc = new Schema(ParentSchemaDef, {typePojoToMixed: false});
+    const ParentSchemaNotSubdoc = new Schema(ParentSchemaDef, { typePojoToMixed: false });
     it('does not create a path for child in either option', function(done) {
       assert.equal(ParentSchemaNotMixed.paths['child.name'].instance, 'String');
       assert.equal(ParentSchemaNotSubdoc.paths['child.name'].instance, 'String');
diff --git a/test/types.map.test.js b/test/types.map.test.js
index b4026fb999b..8391587bfc6 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -655,7 +655,7 @@ describe('Map', function() {
     return co(function*() {
       const first = yield Parent.create({
         children: {
-          one: {name: 'foo'}
+          one: { name: 'foo' }
         }
       });
 
diff --git a/test/types.subdocument.test.js b/test/types.subdocument.test.js
index 2c583625e39..51178ebe54e 100644
--- a/test/types.subdocument.test.js
+++ b/test/types.subdocument.test.js
@@ -90,7 +90,7 @@ describe('types.subdocument', function() {
         };
         return Thing.updateOne({
           _id: id
-        }, {$set: thingy2});
+        }, { $set: thingy2 });
       });
   });
 
diff --git a/test/updateValidators.unit.test.js b/test/updateValidators.unit.test.js
index 05777cff75a..62a545261e6 100644
--- a/test/updateValidators.unit.test.js
+++ b/test/updateValidators.unit.test.js
@@ -18,8 +18,8 @@ describe('updateValidators', function() {
     };
     schema._getSchema.calls = [];
     schema.doValidate = function(v, cb) {
-      schema.doValidate.calls.push({v: v, cb: cb});
-      schema.doValidate.emitter.emit('called', {v: v, cb: cb});
+      schema.doValidate.calls.push({ v: v, cb: cb });
+      schema.doValidate.emitter.emit('called', { v: v, cb: cb });
     };
     schema.doValidate.calls = [];
     schema.doValidate.emitter = new emitter();
@@ -27,7 +27,7 @@ describe('updateValidators', function() {
 
   describe('validators', function() {
     it('flattens paths', function(done) {
-      const fn = updateValidators({}, schema, {test: {a: 1, b: null}}, {});
+      const fn = updateValidators({}, schema, { test: { a: 1, b: null } }, {});
       schema.doValidate.emitter.on('called', function(args) {
         args.cb();
       });
@@ -50,7 +50,7 @@ describe('updateValidators', function() {
 
     it('doesnt flatten dates (gh-3194)', function(done) {
       const dt = new Date();
-      const fn = updateValidators({}, schema, {test: dt}, {});
+      const fn = updateValidators({}, schema, { test: dt }, {});
       schema.doValidate.emitter.on('called', function(args) {
         args.cb();
       });
@@ -65,7 +65,7 @@ describe('updateValidators', function() {
     });
 
     it('doesnt flatten empty arrays (gh-3554)', function(done) {
-      const fn = updateValidators({}, schema, {test: []}, {});
+      const fn = updateValidators({}, schema, { test: [] }, {});
       schema.doValidate.emitter.on('called', function(args) {
         args.cb();
       });
diff --git a/test/utils.test.js b/test/utils.test.js
index 3fe9ac31a03..d9af31b15d4 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -133,8 +133,8 @@ describe('utils', function() {
   });
 
   it('utils.options', function(done) {
-    const o = {a: 1, b: 2, c: 3, 0: 'zero1'};
-    const defaults = {b: 10, d: 20, 0: 'zero2'};
+    const o = { a: 1, b: 2, c: 3, 0: 'zero1' };
+    const defaults = { b: 10, d: 20, 0: 'zero2' };
     const result = utils.options(defaults, o);
     assert.equal(result.a, 1);
     assert.equal(result.b, 2);
@@ -170,7 +170,7 @@ describe('utils', function() {
 
   it('deepEquals on MongooseDocumentArray works', function(done) {
     const db = start();
-    const A = new Schema({a: String});
+    const A = new Schema({ a: String });
     const M = db.model('deepEqualsOnMongooseDocArray', new Schema({
       a1: [A],
       a2: [A]
@@ -179,7 +179,7 @@ describe('utils', function() {
     db.close();
 
     const m1 = new M({
-      a1: [{a: 'Hi'}, {a: 'Bye'}]
+      a1: [{ a: 'Hi' }, { a: 'Bye' }]
     });
 
     m1.a2 = m1.a1;
diff --git a/test/versioning.test.js b/test/versioning.test.js
index e5b127d1d3b..d04cc496502 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -79,18 +79,18 @@ describe('versioning', function() {
     doc.meta.visitors = 34;
     doc.meta.numbers = [12, 11, 10];
     doc.meta.nested = [
-      {title: 'does it work?', date: new Date},
-      {title: '1', comments: [{title: 'this is sub #1'}, {title: 'this is sub #2'}]},
-      {title: '2', comments: [{title: 'this is sub #3'}, {title: 'this is sub #4'}]},
-      {title: 'hi', date: new Date}
+      { title: 'does it work?', date: new Date },
+      { title: '1', comments: [{ title: 'this is sub #1' }, { title: 'this is sub #2' }] },
+      { title: '2', comments: [{ title: 'this is sub #3' }, { title: 'this is sub #4' }] },
+      { title: 'hi', date: new Date }
     ];
-    doc.mixed = {arr: [12, 11, 10]};
+    doc.mixed = { arr: [12, 11, 10] };
     doc.numbers = [3, 4, 5, 6, 7];
     doc.comments = [
-      {title: 'comments 0', date: new Date},
-      {title: 'comments 1', comments: [{title: 'comments.1.comments.1'}, {title: 'comments.1.comments.2'}]},
-      {title: 'coments 2', comments: [{title: 'comments.2.comments.1'}, {title: 'comments.2.comments.2'}]},
-      {title: 'comments 3', date: new Date}
+      { title: 'comments 0', date: new Date },
+      { title: 'comments 1', comments: [{ title: 'comments.1.comments.1' }, { title: 'comments.1.comments.2' }] },
+      { title: 'coments 2', comments: [{ title: 'comments.2.comments.1' }, { title: 'comments.2.comments.2' }] },
+      { title: 'comments 3', date: new Date }
     ];
     doc.arr = [['2d']];
 
@@ -157,8 +157,8 @@ describe('versioning', function() {
       assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
       assert.equal(a.comments.length, 5);
 
-      a.comments.addToSet({title: 'aven'});
-      a.comments.addToSet({title: 'avengers'});
+      a.comments.addToSet({ title: 'aven' });
+      a.comments.addToSet({ title: 'avengers' });
       let d = a.$__delta();
 
       assert.equal(d[0].__v, undefined, 'version should not be included in where clause');
@@ -183,7 +183,7 @@ describe('versioning', function() {
       assert.equal(a.mixed.arr[5], 'woot');
       assert.equal(a.mixed.arr[3][0], 10);
 
-      a.comments.addToSet({title: 'monkey'});
+      a.comments.addToSet({ title: 'monkey' });
       b.markModified('comments');
 
       const d = b.$__delta();
@@ -199,7 +199,7 @@ describe('versioning', function() {
       assert.equal(b.meta.nested[1].comments[0].title, 'sub one');
       assert.equal(a._doc.__v, 10);
       assert.equal(a.mixed.arr.length, 3);
-      a.mixed.arr.push([10], {x: 1}, 'woot');
+      a.mixed.arr.push([10], { x: 1 }, 'woot');
       a.markModified('mixed.arr');
       save(a, b, test11);
     }
@@ -224,9 +224,9 @@ describe('versioning', function() {
       assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
       assert.equal(a.meta.nested.length, 3);
       assert.equal(a._doc.__v, 8);
-      a.meta.nested.push({title: 'the'});
-      a.meta.nested.push({title: 'killing'});
-      b.meta.nested.push({title: 'biutiful'});
+      a.meta.nested.push({ title: 'the' });
+      a.meta.nested.push({ title: 'killing' });
+      b.meta.nested.push({ title: 'biutiful' });
       save(a, b, test9);
     }
 
@@ -336,10 +336,10 @@ describe('versioning', function() {
     const doc = new V;
     doc.numbers = [3, 4, 5, 6, 7];
     doc.comments = [
-      {title: 'does it work?', date: new Date},
-      {title: '1', comments: [{title: 'this is sub #1'}, {title: 'this is sub #2'}]},
-      {title: '2', comments: [{title: 'this is sub #3'}, {title: 'this is sub #4'}]},
-      {title: 'hi', date: new Date}
+      { title: 'does it work?', date: new Date },
+      { title: '1', comments: [{ title: 'this is sub #1' }, { title: 'this is sub #2' }] },
+      { title: '2', comments: [{ title: 'this is sub #3' }, { title: 'this is sub #4' }] },
+      { title: 'hi', date: new Date }
     ];
 
     function test(err) {
@@ -358,9 +358,9 @@ describe('versioning', function() {
   });
 
   it('version works with strict docs', function(done) {
-    const schema = new Schema({str: ['string']}, {strict: true, collection: 'versionstrict_' + random()});
+    const schema = new Schema({ str: ['string'] }, { strict: true, collection: 'versionstrict_' + random() });
     const M = db.model('VersionStrict', schema);
-    const m = new M({str: ['death', 'to', 'smootchy']});
+    const m = new M({ str: ['death', 'to', 'smootchy'] });
     m.save(function(err) {
       assert.ifError(err);
       M.find(m, function(err, m) {
@@ -386,9 +386,9 @@ describe('versioning', function() {
   it('version works with existing unversioned docs', function(done) {
     const V = db.model('Versioning');
 
-    V.collection.insertOne({title: 'unversioned', numbers: [1, 2, 3]}, {safe: true}, function(err) {
+    V.collection.insertOne({ title: 'unversioned', numbers: [1, 2, 3] }, { safe: true }, function(err) {
       assert.ifError(err);
-      V.findOne({title: 'unversioned'}, function(err, d) {
+      V.findOne({ title: 'unversioned' }, function(err, d) {
         assert.ifError(err);
         assert.ok(!d._doc.__v);
         d.numbers.splice(1, 1, 10);
@@ -411,10 +411,10 @@ describe('versioning', function() {
 
   it('versionKey is configurable', function(done) {
     const schema = new Schema(
-      {configured: 'bool'},
-      {versionKey: 'lolwat', collection: 'configuredversion' + random()});
+      { configured: 'bool' },
+      { versionKey: 'lolwat', collection: 'configuredversion' + random() });
     const V = db.model('ConfiguredVersionKey', schema);
-    const v = new V({configured: true});
+    const v = new V({ configured: true });
     v.save(function(err) {
       assert.ifError(err);
       V.findById(v, function(err1, v) {
@@ -426,9 +426,9 @@ describe('versioning', function() {
   });
 
   it('can be disabled', function(done) {
-    const schema = new Schema({x: ['string']}, {versionKey: false});
+    const schema = new Schema({ x: ['string'] }, { versionKey: false });
     const M = db.model('disabledVersioning', schema, 's' + random());
-    M.create({x: ['hi']}, function(err, doc) {
+    M.create({ x: ['hi'] }, function(err, doc) {
       assert.ifError(err);
       assert.equal('__v' in doc._doc, false);
       doc.x.pull('hi');
@@ -440,7 +440,7 @@ describe('versioning', function() {
         const d = doc.$__delta()[0];
         assert.equal(d.__v, undefined, 'version should not be added to where clause');
 
-        M.collection.findOne({_id: doc._id}, function(err, doc) {
+        M.collection.findOne({ _id: doc._id }, function(err, doc) {
           assert.equal('__v' in doc, false);
           done();
         });
@@ -450,7 +450,7 @@ describe('versioning', function() {
 
   it('works with numbericAlpha paths', function(done) {
     const M = db.model('Versioning');
-    const m = new M({mixed: {}});
+    const m = new M({ mixed: {} });
     const path = 'mixed.4a';
     m.set(path, 2);
     m.save(function(err) {
@@ -487,23 +487,23 @@ describe('versioning', function() {
 
   describe('versioning is off', function() {
     it('when { safe: false } is set (gh-1520)', function(done) {
-      const schema1 = new Schema({title: String}, {safe: false});
+      const schema1 = new Schema({ title: String }, { safe: false });
       assert.equal(schema1.options.versionKey, false);
       done();
     });
     it('when { safe: { w: 0 }} is set (gh-1520)', function(done) {
-      const schema1 = new Schema({title: String}, {safe: {w: 0}});
+      const schema1 = new Schema({ title: String }, { safe: { w: 0 } });
       assert.equal(schema1.options.versionKey, false);
       done();
     });
   });
 
   it('gh-1898', function(done) {
-    const schema = new Schema({tags: [String], name: String});
+    const schema = new Schema({ tags: [String], name: String });
 
     const M = db.model('gh-1898', schema, 'gh-1898');
 
-    const m = new M({tags: ['eggs']});
+    const m = new M({ tags: ['eggs'] });
 
     m.save(function(err) {
       assert.ifError(err);
@@ -520,7 +520,7 @@ describe('versioning', function() {
   });
 
   it('can remove version key from toObject() (gh-2675)', function(done) {
-    const schema = new Schema({name: String});
+    const schema = new Schema({ name: String });
     const M = db.model('gh2675', schema, 'gh2675');
 
     const m = new M();
@@ -528,7 +528,7 @@ describe('versioning', function() {
       assert.ifError(err);
       let obj = m.toObject();
       assert.equal(obj.__v, 0);
-      obj = m.toObject({versionKey: false});
+      obj = m.toObject({ versionKey: false });
       assert.equal(obj.__v, undefined);
       done();
     });
@@ -536,7 +536,7 @@ describe('versioning', function() {
 
   it('pull doesnt add version where clause (gh-6190)', function() {
     const User = db.model('gh6190_User', new mongoose.Schema({
-      unreadPosts: [{type: mongoose.Schema.Types.ObjectId}]
+      unreadPosts: [{ type: mongoose.Schema.Types.ObjectId }]
     }));
 
     return co(function*() {
diff --git a/website.js b/website.js
index a0e0376344f..b2bc4630993 100644
--- a/website.js
+++ b/website.js
@@ -144,7 +144,7 @@ files.forEach(function(file) {
   pugify(filename, filemap[file]);
 
   if (process.argv[2] === '--watch') {
-    fs.watchFile(filename, {interval: 1000}, function(cur, prev) {
+    fs.watchFile(filename, { interval: 1000 }, function(cur, prev) {
       if (cur.mtime > prev.mtime) {
         pugify(filename, filemap[file]);
       }

From 9dad45fd01000a0f3f463bb970eee53d959eded3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Mar 2020 09:29:11 -0600
Subject: [PATCH 0583/2348] chore: update opencollective sponsors

---
 index.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.pug b/index.pug
index 71f83e3d36c..a2cf38f702e 100644
--- a/index.pug
+++ b/index.pug
@@ -292,6 +292,12 @@ html(lang='en')
               <a href="https://www.pelisivut.com/">
                 <img class="sponsor" src="https://images.opencollective.com/pelisivut/04f08f2/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.kasinot.fi/">
+                <img class="sponsor" src="https://images.opencollective.com/kasinot-fi/e09aa2e/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://www.coinnewsspan.com/">
+                <img class="sponsor" src="https://images.opencollective.com/coinnewsspan/c0933b4/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 7d01159d68a4ae141a2308ad1379d9caa6b265bd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Mar 2020 14:45:32 -0600
Subject: [PATCH 0584/2348] docs(findOneAndUpdate): add a section about the
 `rawResult` option

Fix #8662
---
 docs/tutorials/findoneandupdate.md        | 28 +++++++++++++++++++++++
 test/es-next/findoneandupdate.test.es6.js | 25 ++++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/docs/tutorials/findoneandupdate.md b/docs/tutorials/findoneandupdate.md
index 5bf37ebdcb0..f1be1cdc4b4 100644
--- a/docs/tutorials/findoneandupdate.md
+++ b/docs/tutorials/findoneandupdate.md
@@ -38,4 +38,32 @@ Using the `upsert` option, you can use `findOneAndUpdate()` as a find-and-[upser
 
 ```javascript
 [require:Tutorial.*findOneAndUpdate.*upsert]
+```
+
+<h2 id="raw-result">The `rawResult` Option</h2>
+
+Mongoose transforms the result of `findOneAndUpdate()` by default: it
+returns the updated document. That makes it difficult to check whether
+a document was upserted or not. In order to get the updated document
+and check whether MongoDB upserted a new document in the same operation,
+you can set the `rawResult` flag to make Mongoose return the raw result
+from MongoDB.
+
+```javascript
+[require:Tutorial.*findOneAndUpdate.*rawResult$]
+```
+
+Here's what the `res` object from the above example looks like:
+
+```
+{ lastErrorObject:
+   { n: 1,
+     updatedExisting: false,
+     upserted: 5e6a9e5ec6e44398ae2ac16a },
+  value:
+   { _id: 5e6a9e5ec6e44398ae2ac16a,
+     name: 'Will Riker',
+     __v: 0,
+     age: 29 },
+  ok: 1 }
 ```
\ No newline at end of file
diff --git a/test/es-next/findoneandupdate.test.es6.js b/test/es-next/findoneandupdate.test.es6.js
index 1b90db5089c..72b4afe0243 100644
--- a/test/es-next/findoneandupdate.test.es6.js
+++ b/test/es-next/findoneandupdate.test.es6.js
@@ -121,4 +121,29 @@ describe('Tutorial: findOneAndUpdate()', function() {
     assert.equal(doc.age, 29);
     // acquit:ignore:end
   });
+
+  it('rawResult', async function() {
+    const filter = { name: 'Will Riker' };
+    const update = { age: 29 };
+
+    await Character.countDocuments(filter); // 0
+    // acquit:ignore:start
+    assert.equal(await Character.countDocuments(filter), 0);
+    // acquit:ignore:end
+
+    let res = await Character.findOneAndUpdate(filter, update, {
+      new: true,
+      upsert: true,
+      rawResult: true // Return the raw result from the MongoDB driver
+    });
+
+    res.value instanceof Character; // true
+    // The below property will be `false` if MongoDB upserted a new
+    // document, and `true` if MongoDB updated an existing object.
+    res.lastErrorObject.updatedExisting; // false
+    // acquit:ignore:start
+    assert.ok(res.value instanceof Character);
+    assert.ok(!res.lastErrorObject.updatedExisting);
+    // acquit:ignore:end
+  });
 });
\ No newline at end of file

From 61cff370733f0e5b112d8592a3b68cb6e480c7a1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 13 Mar 2020 03:14:31 +0200
Subject: [PATCH 0585/2348] Upgrade mongodb driver

---
 package.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 8ee4a3d4d19..95c8b9ede34 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "~1.1.1",
     "kareem": "2.3.1",
-    "mongodb": "3.5.4",
+    "mongodb": "3.5.5",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.6.0",
     "mquery": "3.2.2",
@@ -164,4 +164,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
+}
\ No newline at end of file

From 698bbd3e2aa7ddfd2576c06887fae3c0f1e18415 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 13 Mar 2020 08:53:17 +0200
Subject: [PATCH 0586/2348] Allow pushing to an mongoose core array after
 slicing

---
 lib/types/core_array.js  |  4 ++--
 test/types.array.test.js | 11 +++++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index d09bd8c715e..01ec70bd36a 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -338,8 +338,7 @@ class CoreMongooseArray extends Array {
 
     // check for impossible $atomic combos (Mongo denies more than one
     // $atomic op on a single path
-    if (this[arrayAtomicsSymbol].$set ||
-        Object.keys(atomics).length && !(op in atomics)) {
+    if (this[arrayAtomicsSymbol].$set || Object.keys(atomics).length && !(op in atomics)) {
       // a different op was previously registered.
       // save the entire thing.
       this[arrayAtomicsSymbol] = {$set: this};
@@ -835,6 +834,7 @@ class CoreMongooseArray extends Array {
     const ret = super.slice.apply(this, arguments);
     ret[arrayParentSymbol] = this[arrayParentSymbol];
     ret[arraySchemaSymbol] = this[arraySchemaSymbol];
+    ret[arrayAtomicsSymbol] = this[arrayAtomicsSymbol];
     return ret;
   }
 
diff --git a/test/types.array.test.js b/test/types.array.test.js
index 46dae50a947..6ef36d1577e 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1670,6 +1670,17 @@ describe('types array', function() {
 
       assert.deepEqual(arr, [10, 3]);
     });
+
+    it('with push (gh-8655)', function() {
+      const userSchema = new Schema({ names: [String] });
+      const User = mongoose.model('User', userSchema);
+
+      const user = new User({ names: ['test1', 'test2', 'test3'] });
+
+      const evens = user.names.slice(1, 2);
+      evens.push('test4');
+      assert.ok(evens.includes('test2') && evens.includes('test4'));
+    });
   });
 
   describe('setting a doc array', function() {

From a1edfc353ea3156187319afc2a9de20a2245c7d3 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 13 Mar 2020 08:54:20 +0200
Subject: [PATCH 0587/2348] Change variable name

---
 test/types.array.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/types.array.test.js b/test/types.array.test.js
index 6ef36d1577e..329e4438697 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1677,9 +1677,9 @@ describe('types array', function() {
 
       const user = new User({ names: ['test1', 'test2', 'test3'] });
 
-      const evens = user.names.slice(1, 2);
-      evens.push('test4');
-      assert.ok(evens.includes('test2') && evens.includes('test4'));
+      const slicedNames = user.names.slice(1, 2);
+      slicedNames.push('test4');
+      assert.ok(slicedNames.includes('test2') && slicedNames.includes('test4'));
     });
   });
 

From afe03ae411504f26d01b3dc725f7a55970fa7468 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 13 Mar 2020 09:00:14 +0200
Subject: [PATCH 0588/2348] Use indexOf instead of includes in test

---
 test/types.array.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/types.array.test.js b/test/types.array.test.js
index 329e4438697..28bb9aae7a7 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1679,7 +1679,7 @@ describe('types array', function() {
 
       const slicedNames = user.names.slice(1, 2);
       slicedNames.push('test4');
-      assert.ok(slicedNames.includes('test2') && slicedNames.includes('test4'));
+      assert.ok(slicedNames.indexOf('test2') !== -1 && slicedNames.indexOf('test4') !== -1);
     });
   });
 

From a1f938abdb07f83da58b490a112466664541cc52 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Mar 2020 12:13:40 -0600
Subject: [PATCH 0589/2348] docs: add missing link

---
 docs/tutorials/findoneandupdate.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/tutorials/findoneandupdate.md b/docs/tutorials/findoneandupdate.md
index f1be1cdc4b4..eac1793083f 100644
--- a/docs/tutorials/findoneandupdate.md
+++ b/docs/tutorials/findoneandupdate.md
@@ -5,6 +5,7 @@ The [`findOneAndUpdate()` function in Mongoose](/docs/api.html#query_Query-findO
 * [Getting Started](#getting-started)
 * [Atomic Updates](#atomic-updates)
 * [Upsert](#upsert)
+* [The `rawResult` Option](#raw-result)
 
 <h2 id="getting-started">Getting Started</h2>
 

From 8542fcc887dae166d9827637ba7eb5e50f1d1acf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Mar 2020 12:15:24 -0600
Subject: [PATCH 0590/2348] style: fix lint

---
 test/model.populate.test.js | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5f6483ac6d3..8cb6a5d6e26 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9203,22 +9203,22 @@ describe('model: populate:', function() {
 
   it('throws an error when using limit with perDocumentLimit', function() {
     return co(function *() {
-      const User = db.model('User',userSchema);
-      const BlogPost = db.model('BlogPost',blogPostSchema);
+      const User = db.model('User', userSchema);
+      const BlogPost = db.model('BlogPost', blogPostSchema);
 
-      const blogPosts = yield BlogPost.create([{title:'JS 101'},{title:'Mocha 101'}]);
-      const user = yield User.create({blogposts: blogPosts});
+      const blogPosts = yield BlogPost.create([{ title: 'JS 101' }, { title: 'Mocha 101' }]);
+      const user = yield User.create({ blogposts: blogPosts });
 
 
       let err;
       try {
-        yield User.find({_id:user._id}).populate({ path: 'blogposts', perDocumentLimit: 2,limit:1 });
+        yield User.find({ _id: user._id }).populate({ path: 'blogposts', perDocumentLimit: 2, limit: 1 });
       } catch (error) {
         err = error;
       }
 
       assert(err);
-      assert.equal(err.message,'Can not use `limit` and `perDocumentLimit` at the same time. Path: `blogposts`.');
+      assert.equal(err.message, 'Can not use `limit` and `perDocumentLimit` at the same time. Path: `blogposts`.');
     });
   });
 });
\ No newline at end of file

From 616b50c95e80c054f96c1e1fc64ed4691f67dd12 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Mar 2020 19:15:53 -0400
Subject: [PATCH 0591/2348] test(populate): repro #8657

---
 test/model.populate.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 8cb6a5d6e26..a67de392704 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9078,6 +9078,28 @@ describe('model: populate:', function() {
     });
   });
 
+  it('top-level limit properly applies limit per document (gh-8657)', function() {
+    const Article = db.model('Article', mongoose.Schema({
+      authors: [{ type: Number, ref: 'User' }]
+    }));
+    const User = db.model('User', mongoose.Schema({ _id: Number }));
+
+    return co(function*() {
+      yield Article.create([
+        { authors: [1, 2] },
+        { authors: [3, 4] }
+      ]);
+      yield User.create({ _id: 1 }, { _id: 2 }, { _id: 3 }, { _id: 4 });
+
+      const res = yield Article.find().
+        sort({ _id: 1 }).
+        populate({ path: 'authors', limit: 1, sort: { _id: 1 } });
+      assert.equal(res.length, 2);
+      assert.deepEqual(res[0].authors.map(a => a._id), [1]);
+      assert.deepEqual(res[1].toObject().authors, []);
+    });
+  });
+
   it('correct limit with populate (gh-7318)', function() {
     const childSchema = Schema({ _id: Number, parentId: 'ObjectId' });
 

From 2c07b5c622bbddc4b5dd0e66e26095a7d79c2605 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Mar 2020 19:16:05 -0400
Subject: [PATCH 0592/2348] fix(populate): ensure top-level `limit` applies if
 one document being populated has more than `limit` results

Fix #8657
---
 lib/model.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index dae0346e9a6..13ad9e5f871 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4377,8 +4377,10 @@ function populate(model, docs, options, callback) {
       }
     }
 
-    if (mod.options.options && mod.options.options.limit) {
+    if (mod.options.options && mod.options.options.limit != null) {
       assignmentOpts.originalLimit = mod.options.options.limit;
+    } else if (mod.options.limit != null) {
+      assignmentOpts.originalLimit = mod.options.limit;
     }
 
     params.push([mod, match, select, assignmentOpts, _next]);

From 94d88227dba057343496420ab8989acb1dfc3d26 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Mar 2020 19:20:27 -0400
Subject: [PATCH 0593/2348] test: fix tests

---
 test/model.populate.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a67de392704..5c3ce08acc1 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9073,7 +9073,7 @@ describe('model: populate:', function() {
         populate({ path: 'children', skip: 0, limit: 2 });
       assert.equal(docs[0]._id.toString(), p._id.toString());
       assert.equal(docs[1]._id.toString(), p2._id.toString());
-      assert.deepEqual(docs[0].children.map(c => c._id), [1, 2, 3]);
+      assert.deepEqual(docs[0].children.map(c => c._id), [1, 2]);
       assert.deepEqual(docs[1].children.map(c => c._id), [4]);
     });
   });

From ddaa8986565271097ea286eafc14159cc7eea408 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Mar 2020 19:41:27 -0400
Subject: [PATCH 0594/2348] docs(query): improve `Query#populate()` example to
 clarify that `sort` doesn't affect the original result's order

Fix #8647
---
 lib/query.js | 39 ++++++++++++++++++++++-----------------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index cefd977fad9..303983dfd36 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4518,23 +4518,28 @@ function castDoc(query, overwrite) {
  *
  * ####Example:
  *
- *     Kitten.findOne().populate('owner').exec(function (err, kitten) {
- *       console.log(kitten.owner.name) // Max
- *     })
- *
- *     Kitten.find().populate({
- *       path: 'owner',
- *       select: 'name',
- *       match: { color: 'black' },
- *       options: { sort: { name: -1 } }
- *     }).exec(function (err, kittens) {
- *       console.log(kittens[0].owner.name) // Zoopa
- *     })
- *
- *     // alternatively
- *     Kitten.find().populate('owner', 'name', null, {sort: { name: -1 }}).exec(function (err, kittens) {
- *       console.log(kittens[0].owner.name) // Zoopa
- *     })
+ *     let book = await Book.findOne().populate('authors');
+ *     book.title; // 'Node.js in Action'
+ *     book.authors[0].name; // 'TJ Holowaychuk'
+ *     book.authors[1].name; // 'Nathan Rajlich'
+ *
+ *     let books = await Book.find().populate({
+ *       path: 'authors',
+ *       // `match` and `sort` apply to the Author model,
+ *       // not the Book model. These options do not affect
+ *       // which documents are in `books`, just the order and
+ *       // contents of each book document's `authors`.
+ *       match: { name: new RegExp('.*h.*', 'i') },
+ *       sort: { name: -1 }
+ *     });
+ *     books[0].title; // 'Node.js in Action'
+ *     // Each book's `authors` are sorted by name, descending.
+ *     books[0].authors[0].name; // 'TJ Holowaychuk'
+ *     books[0].authors[1].name; // 'Marc Harter'
+ *
+ *     books[1].title; // 'Professional AngularJS'
+ *     // Empty array, no authors' name has the letter 'h'
+ *     books[1].authors; // []
  *
  * Paths are populated after the query executes and a response is received. A
  * separate query is then executed for each path specified for population. After

From 8b1d2dfcde9b8b81bfeb426fe9c70cb4449698cc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Mar 2020 22:20:32 -0400
Subject: [PATCH 0595/2348] test: clean up more unnecessary collections and add
 quick instrumentation to see what collections are used

Re: #8481
---
 test/common.js                            |  21 +++
 test/document.modified.test.js            |   4 +-
 test/document.populate.test.js            | 181 ++++++++++---------
 test/document.test.js                     |  16 +-
 test/model.discriminator.querying.test.js | 130 +++++++-------
 test/model.populate.divergent.test.js     |   6 +-
 test/model.populate.test.js               | 208 +++++++++++-----------
 test/query.cursor.test.js                 |  44 ++---
 test/query.middleware.test.js             |  37 ++--
 test/query.test.js                        |  10 +-
 test/types.map.test.js                    |  61 ++++---
 11 files changed, 377 insertions(+), 341 deletions(-)

diff --git a/test/common.js b/test/common.js
index 7c6968b96d8..68ef4b44f0c 100644
--- a/test/common.js
+++ b/test/common.js
@@ -10,10 +10,16 @@ const Collection = mongoose.Collection;
 const assert = require('assert');
 
 let server;
+const collectionNames = new Map();
 
 if (process.env.D === '1') {
   mongoose.set('debug', true);
 }
+if (process.env.PRINT_COLLECTIONS) {
+  after(function() {
+    console.log('Colls', Array.from(collectionNames.entries()).sort((a, b) => a[1] - b[1]));
+  });
+}
 
 // For 3.1.3 deprecations
 mongoose.set('useFindAndModify', false);
@@ -91,6 +97,21 @@ module.exports = function(options) {
 
   const conn = mongoose.createConnection(uri, options);
 
+  const model = conn.model;
+  conn.model = function(name, schema, collection) {
+    if (schema == null || schema._baseSchema != null) {
+      // 2 cases: if calling `db.model(name)` to retrieve a model,
+      // or if declaring a discriminator, skip adding the model name.
+      return model.apply(this, arguments);
+    }
+
+    const collName = collection == null ? mongoose.pluralize(name) : collection;
+
+    let count = collectionNames.get(collName) || 0;
+    collectionNames.set(collName, ++count);
+    return model.apply(this, arguments);
+  };
+
   if (noErrorListener) {
     return conn;
   }
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 049ff975c38..dd33084165f 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -356,8 +356,8 @@ describe('document modified', function() {
         child: { type: Schema.Types.ObjectId, ref: 'Child' }
       });
 
-      const Parent = db.model('Parent', parentSchema, 'parents');
-      const Child = db.model('Child', parentSchema, 'children');
+      const Parent = db.model('Parent', parentSchema);
+      const Child = db.model('Child', parentSchema);
 
       const child = new Child({ name: 'Mary' });
       const p = new Parent({ name: 'Alex', child: child });
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index e8957e921c2..a351fb3f617 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -13,7 +13,6 @@ const co = require('co');
 const utils = require('../lib/utils');
 
 const mongoose = start.mongoose;
-const random = utils.random;
 const Schema = mongoose.Schema;
 const ObjectId = Schema.ObjectId;
 
@@ -71,21 +70,21 @@ TestDocument.prototype.$__setSchema(schema);
  * User schema.
  */
 
-const User = new Schema({
+const UserSchema = new Schema({
   name: String,
   email: String,
   gender: { type: String, enum: ['male', 'female'], default: 'male' },
   age: { type: Number, default: 21 },
-  blogposts: [{ type: ObjectId, ref: 'doc.populate.b' }]
-}, { collection: 'doc.populate.us' });
+  blogposts: [{ type: ObjectId, ref: 'BlogPost' }]
+});
 
 /**
  * Comment subdocument schema.
  */
 
-const Comment = new Schema({
-  asers: [{ type: ObjectId, ref: 'doc.populate.u' }],
-  _creator: { type: ObjectId, ref: 'doc.populate.u' },
+const CommentSchema = new Schema({
+  asers: [{ type: ObjectId, ref: 'User' }],
+  _creator: { type: ObjectId, ref: 'User' },
   content: String
 });
 
@@ -93,25 +92,28 @@ const Comment = new Schema({
  * Blog post schema.
  */
 
-const BlogPost = new Schema({
-  _creator: { type: ObjectId, ref: 'doc.populate.u' },
+const BlogPostSchema = new Schema({
+  _creator: { type: ObjectId, ref: 'User' },
   title: String,
-  comments: [Comment],
-  fans: [{ type: ObjectId, ref: 'doc.populate.u' }]
+  comments: [CommentSchema],
+  fans: [{ type: ObjectId, ref: 'User' }]
 });
 
-mongoose.model('doc.populate.b', BlogPost);
-mongoose.model('doc.populate.u', User);
-mongoose.model('doc.populate.u2', User);
-
 describe('document.populate', function() {
   let db, B, User;
   let user1, user2, post, _id;
 
-  before(function(done) {
+  before(function() {
     db = start();
-    B = db.model('doc.populate.b');
-    User = db.model('doc.populate.u');
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function(done) {
+    B = db.model('BlogPost', BlogPostSchema);
+    User = db.model('User', UserSchema);
 
     _id = new mongoose.Types.ObjectId;
 
@@ -294,7 +296,7 @@ describe('document.populate', function() {
       param.select = '-email';
       param.options = { sort: 'name' };
       param.path = '_creator fans';
-      param.model = 'doc.populate.u2';
+      param.model = 'User';
 
       const creator_id = post._creator;
       const alt_id = post.fans[1];
@@ -323,7 +325,7 @@ describe('document.populate', function() {
         post.$__setValue('idontexist', user1._id);
 
         // populate the non-schema value by passing an explicit model
-        post.populate({ path: 'idontexist', model: 'doc.populate.u' }, function(err, post) {
+        post.populate({ path: 'idontexist', model: 'User' }, function(err, post) {
           assert.ifError(err);
           assert.ok(post);
           assert.equal(user1._id.toString(), post.get('idontexist')._id);
@@ -371,12 +373,13 @@ describe('document.populate', function() {
     });
 
     const NoteSchema = new Schema({
-      author: { type: String, ref: 'UserWithStringId' },
+      author: { type: String, ref: 'User' },
       body: String
     });
 
-    const User = db.model('UserWithStringId', UserSchema, random());
-    const Note = db.model('NoteWithStringId', NoteSchema, random());
+    db.deleteModel(/User/);
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({ _id: 'alice', name: 'Alice In Wonderland' });
 
@@ -401,12 +404,13 @@ describe('document.populate', function() {
     });
 
     const NoteSchema = new Schema({
-      author: { type: Buffer, ref: 'UserWithBufferId' },
+      author: { type: Buffer, ref: 'User' },
       body: String
     });
 
-    const User = db.model('UserWithBufferId', UserSchema, random());
-    const Note = db.model('NoteWithBufferId', NoteSchema, random());
+    db.deleteModel(/User/);
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({ _id: new mongoose.Types.Buffer('YWxpY2U=', 'base64'), name: 'Alice' });
 
@@ -439,12 +443,13 @@ describe('document.populate', function() {
     });
 
     const NoteSchema = new Schema({
-      author: { type: Number, ref: 'UserWithNumberId' },
+      author: { type: Number, ref: 'User' },
       body: String
     });
 
-    const User = db.model('UserWithNumberId', UserSchema, random());
-    const Note = db.model('NoteWithNumberId', NoteSchema, random());
+    db.deleteModel(/User/);
+    const User = db.model('User', UserSchema);
+    const Note = db.model('Test', NoteSchema);
 
     const alice = new User({ _id: 2359, name: 'Alice' });
 
@@ -493,13 +498,13 @@ describe('document.populate', function() {
     });
   });
 
-  it('gh-3308', function(done) {
-    const Person = db.model('gh3308', {
+  it('depopulates when setting `_id` (gh-3308)', function(done) {
+    const Person = db.model('Person', {
       name: String
     });
 
-    const Band = db.model('gh3308_0', {
-      guitarist: { type: Schema.Types.ObjectId, ref: 'gh3308' }
+    const Band = db.model('Band', {
+      guitarist: { type: Schema.Types.ObjectId, ref: 'Person' }
     });
 
     const slash = new Person({ name: 'Slash' });
@@ -518,17 +523,17 @@ describe('document.populate', function() {
 
   describe('gh-2214', function() {
     it('should return a real document array when populating', function(done) {
-      const Car = db.model('gh-2214-1', {
+      const Car = db.model('Car', {
         color: String,
         model: String
       });
 
-      const Person = db.model('gh-2214-2', {
+      const Person = db.model('Person', {
         name: String,
         cars: [
           {
             type: Schema.Types.ObjectId,
-            ref: 'gh-2214-1'
+            ref: 'Car'
           }
         ]
       });
@@ -566,37 +571,37 @@ describe('document.populate', function() {
 
   describe('gh-7889', function() {
     it('should save item added to array after populating the array', function(done) {
-      const Car = db.model('gh-7889-1', {
+      const Car = db.model('Car', {
         model: Number
       });
 
-      const Player = db.model('gh-7889-2', {
-        cars: [{ type: Schema.Types.ObjectId, ref: 'gh-7889-1' }]
+      const Person = db.model('Person', {
+        cars: [{ type: Schema.Types.ObjectId, ref: 'Car' }]
       });
 
-      let player;
+      let person;
 
       Car.create({ model: 0 }).then(car => {
-        return Player.create({ cars: [car._id] });
+        return Person.create({ cars: [car._id] });
       }).then(() => {
-        return Player.findOne({});
+        return Person.findOne({});
       }).then(p => {
-        player = p;
-        return player.populate('cars').execPopulate();
+        person = p;
+        return person.populate('cars').execPopulate();
       }).then(() => {
         return Car.create({ model: 1 });
       }).then(car => {
-        player.cars.push(car);
-        return player.populate('cars').execPopulate();
+        person.cars.push(car);
+        return person.populate('cars').execPopulate();
       }).then(() => {
         return Car.create({ model: 2 });
       }).then(car => {
-        player.cars.push(car);
-        return player.save();
+        person.cars.push(car);
+        return person.save();
       }).then(() => {
-        return Player.findOne({});
-      }).then(player => {
-        assert.equal(player.cars.length, 3);
+        return Person.findOne({});
+      }).then(person => {
+        assert.equal(person.cars.length, 3);
         done();
       });
     });
@@ -604,14 +609,14 @@ describe('document.populate', function() {
 
   describe('depopulate', function() {
     it('can depopulate specific path (gh-2509)', function(done) {
-      const Person = db.model('gh2509_1', {
+      const Person = db.model('Person', {
         name: String
       });
 
-      const Band = db.model('gh2509_2', {
+      const Band = db.model('Band', {
         name: String,
-        members: [{ type: Schema.Types.ObjectId, ref: 'gh2509_1' }],
-        lead: { type: Schema.Types.ObjectId, ref: 'gh2509_1' }
+        members: [{ type: Schema.Types.ObjectId, ref: 'Person' }],
+        lead: { type: Schema.Types.ObjectId, ref: 'Person' }
       });
 
       const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
@@ -644,14 +649,14 @@ describe('document.populate', function() {
     });
 
     it('depopulates all (gh-6073)', function(done) {
-      const Person = db.model('gh6073_1', {
+      const Person = db.model('Person', {
         name: String
       });
 
-      const Band = db.model('gh6073_2', {
+      const Band = db.model('Band', {
         name: String,
-        members: [{ type: Schema.Types.ObjectId, ref: 'gh6073_1' }],
-        lead: { type: Schema.Types.ObjectId, ref: 'gh6073_1' }
+        members: [{ type: Schema.Types.ObjectId, ref: 'Person' }],
+        lead: { type: Schema.Types.ObjectId, ref: 'Person' }
       });
 
       const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
@@ -677,7 +682,7 @@ describe('document.populate', function() {
     });
 
     it('doesn\'t throw when called on a doc that is not populated (gh-6075)', function(done) {
-      const Person = db.model('gh6075', {
+      const Person = db.model('Person', {
         name: String
       });
 
@@ -705,27 +710,27 @@ describe('document.populate', function() {
       }, { toJSON: { virtuals: true } });
 
       schema.virtual('$others', {
-        ref: 'gh6075_other',
+        ref: 'Test',
         localField: 'others',
         foreignField: 'val'
       });
 
       schema.virtual('$single', {
-        ref: 'gh6075_other',
+        ref: 'Test',
         localField: 'single',
         foreignField: 'val',
         justOne: true
       });
 
       schema.virtual('$last', {
-        ref: 'gh6075_other',
+        ref: 'Test',
         localField: 'single',
         foreignField: 'val',
         justOne: true
       });
 
-      const Other = db.model('gh6075_other', otherSchema);
-      const Test = db.model('gh6075_test', schema);
+      const Other = db.model('Test', otherSchema);
+      const Test = db.model('Test1', schema);
 
       const others = 'abc'.split('').map(c => {
         return new Other({
@@ -764,17 +769,17 @@ describe('document.populate', function() {
 
     it('depopulates field with empty array (gh-7740)', function() {
       db.model(
-        'gh_7740_1',
+        'Book',
         new mongoose.Schema({
           name: String,
           chapters: Number
         })
       );
       const Author = db.model(
-        'gh_7740_2',
+        'Person',
         new mongoose.Schema({
           name: String,
-          books: { type: [{ type: mongoose.Schema.Types.ObjectId, ref: 'gh_7740_1' }], default: [] }
+          books: { type: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Book' }], default: [] }
         })
       );
 
@@ -806,7 +811,7 @@ describe('document.populate', function() {
       embedded: EmbeddedSchema
     });
 
-    const Model = db.model('gh4552', ModelSchema);
+    const Model = db.model('Test', ModelSchema);
 
     const m = new Model({});
     m.embedded = {};
@@ -819,16 +824,16 @@ describe('document.populate', function() {
   it('handles pulling from populated array (gh-3579)', function(done) {
     const barSchema = new Schema({ name: String });
 
-    const Bar = db.model('gh3579', barSchema);
+    const Bar = db.model('Test', barSchema);
 
     const fooSchema = new Schema({
       bars: [{
         type: Schema.Types.ObjectId,
-        ref: 'gh3579'
+        ref: 'Test'
       }]
     });
 
-    const Foo = db.model('gh3579_0', fooSchema);
+    const Foo = db.model('Test1', fooSchema);
 
     Bar.create([{ name: 'bar1' }, { name: 'bar2' }], function(error, docs) {
       assert.ifError(error);
@@ -849,12 +854,12 @@ describe('document.populate', function() {
   describe('#populated() with virtuals (gh-7440)', function() {
     let Team;
 
-    before(function() {
+    beforeEach(function() {
       const teamSchema = mongoose.Schema({
         name: String,
         captain: String
       });
-      Team = db.model('gh7440_Team', teamSchema);
+      Team = db.model('Test', teamSchema);
     });
 
     it('works with justOne: false', function() {
@@ -863,11 +868,11 @@ describe('document.populate', function() {
         name: String
       });
       playerSchema.virtual('teams', {
-        ref: 'gh7440_Team',
+        ref: 'Test',
         localField: '_id',
         foreignField: 'captain'
       });
-      const Player = db.model('gh7440_Player_0', playerSchema);
+      const Player = db.model('Person', playerSchema);
 
       return co(function*() {
         const player = yield Player.create({ name: 'Derek Jeter', _id: 'test1' });
@@ -884,12 +889,12 @@ describe('document.populate', function() {
         name: String
       });
       playerSchema.virtual('team', {
-        ref: 'gh7440_Team',
+        ref: 'Test',
         localField: '_id',
         foreignField: 'captain',
         justOne: true
       });
-      const Player = db.model('gh7440_Player_1', playerSchema);
+      const Player = db.model('Person', playerSchema);
 
       return co(function*() {
         const player = yield Player.create({ name: 'Derek Jeter', _id: 'test1' });
@@ -905,7 +910,7 @@ describe('document.populate', function() {
     let Team;
     let Player;
 
-    before(function() {
+    beforeEach(function() {
       const playerSchema = mongoose.Schema({
         _id: String
       });
@@ -913,7 +918,7 @@ describe('document.populate', function() {
       const teamSchema = mongoose.Schema({
         captain: {
           type: String,
-          ref: 'gh7521_Player',
+          ref: 'Person',
           get: (v) => {
             if (!v || typeof v !== 'string') {
               return v;
@@ -925,7 +930,7 @@ describe('document.populate', function() {
         players: [new mongoose.Schema({
           player: {
             type: String,
-            ref: 'gh7521_Player',
+            ref: 'Person',
             get: (v) => {
               if (!v || typeof v !== 'string') {
                 return v;
@@ -937,8 +942,8 @@ describe('document.populate', function() {
         })]
       });
 
-      Player = db.model('gh7521_Player', playerSchema);
-      Team = db.model('gh7521_Team', teamSchema);
+      Player = db.model('Person', playerSchema);
+      Team = db.model('Test', teamSchema);
     });
 
     it('works with populate', function() {
@@ -968,19 +973,19 @@ describe('document.populate', function() {
     const schema2 = mongoose.Schema({
       g: {
         type: mongoose.ObjectId,
-        ref: 'gh7685_1'
+        ref: 'Test1'
       }
     });
     const schema3 = mongoose.Schema({
       i: {
         type: mongoose.Schema.Types.ObjectId,
-        ref: 'gh7685_2'
+        ref: 'Test2'
       }
     });
 
-    const M = db.model('gh7685_1', schema);
-    const N = db.model('gh7685_2', schema2);
-    const O = db.model('gh7685_3', schema3);
+    const M = db.model('Test1', schema);
+    const N = db.model('Test2', schema2);
+    const O = db.model('Test3', schema3);
 
     return co(function*() {
       const m = yield M.create({ a: 'TEST' });
diff --git a/test/document.test.js b/test/document.test.js
index f608013633f..507051ffd3a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -764,7 +764,7 @@ describe('document', function() {
 
       postSchema.set('toObject', { virtuals: true });
       const User = db.model('User', userSchema);
-      const Post = db.model('Post', postSchema);
+      const Post = db.model('BlogPost', postSchema);
 
       const user = new User({ firstName: 'Joe', lastName: 'Smith', password: 'password' });
 
@@ -1016,7 +1016,7 @@ describe('document', function() {
       });
 
       const User = db.model('User', UserSchema);
-      const Post = db.model('Post', PostSchema);
+      const Post = db.model('BlogPost', PostSchema);
 
       const val = new User({ name: 'Val' });
       const post = new Post({ title: 'Test', postedBy: val._id });
@@ -1039,17 +1039,17 @@ describe('document', function() {
 
     it('populate on nested path (gh-5703)', function() {
       const toySchema = new mongoose.Schema({ color: String });
-      const Toy = db.model('Toy', toySchema);
+      const Toy = db.model('Cat', toySchema);
 
       const childSchema = new mongoose.Schema({
         name: String,
         values: {
-          toy: { type: mongoose.Schema.Types.ObjectId, ref: 'Toy' }
+          toy: { type: mongoose.Schema.Types.ObjectId, ref: 'Cat' }
         }
       });
       const Child = db.model('Child', childSchema);
 
-      return Toy.create({ color: 'blue' }).
+      return Toy.create({ color: 'brown' }).
         then(function(toy) {
           return Child.create({ values: { toy: toy._id } });
         }).
@@ -1062,7 +1062,7 @@ describe('document', function() {
           });
         }).
         then(function(child) {
-          assert.equal(child.values.toy.color, 'blue');
+          assert.equal(child.values.toy.color, 'brown');
         });
     });
   });
@@ -1464,7 +1464,7 @@ describe('document', function() {
         controls: [Control]
       });
 
-      const Post = db.model('Post', PostSchema);
+      const Post = db.model('BlogPost', PostSchema);
 
       const post = new Post({
         controls: [{
@@ -1497,7 +1497,7 @@ describe('document', function() {
         controls: [Control]
       });
 
-      const Post = db.model('Post', PostSchema);
+      const Post = db.model('BlogPost', PostSchema);
 
       const post = new Post({
         controls: [{
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 2c05cbcc876..9b4d1c823b9 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -8,7 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 const util = require('util');
 
 const mongoose = start.mongoose;
@@ -42,38 +41,38 @@ describe('model', function() {
 
     before(function() {
       db = start();
-      BaseEvent = db.model('model-discriminator-querying-event', EventSchema, 'model-discriminator-querying-' + random());
-      ImpressionEvent = BaseEvent.discriminator('model-discriminator-querying-impression', ImpressionEventSchema);
-      ConversionEvent = BaseEvent.discriminator('model-discriminator-querying-conversion', ConversionEventSchema);
-      SecretEvent = BaseEvent.discriminator('model-discriminator-querying-secret', SecretEventSchema);
     });
 
-    afterEach(function() {
-      return BaseEvent.deleteMany({}).
-        then(() => ImpressionEvent.deleteMany({})).
-        then(() => ConversionEvent.deleteMany({}));
+    beforeEach(() => db.deleteModel(/.*/));
+    beforeEach(() => {
+      BaseEvent = db.model('Event', EventSchema);
+      ImpressionEvent = BaseEvent.discriminator('Impression', ImpressionEventSchema);
+      ConversionEvent = BaseEvent.discriminator('Conversion', ConversionEventSchema);
+      SecretEvent = BaseEvent.discriminator('Secret', SecretEventSchema);
     });
 
+    afterEach(() => require('./util').clearTestData(db));
+
     after(function(done) {
       db.close(done);
     });
 
     describe('pushing discriminated objects', function() {
       let ContainerModel, BaseCustomEvent, DiscCustomEvent;
-      before(function() {
+      beforeEach(function() {
         const BaseCustomEventSchema = new BaseSchema();
         const DiscCustomEventSchema = new BaseSchema({
           personName: Number
         });
-        BaseCustomEvent = db.model('base-custom-event',
+        BaseCustomEvent = db.model('Test',
           BaseCustomEventSchema);
-        DiscCustomEvent = BaseCustomEvent.discriminator('disc-custom-event',
+        DiscCustomEvent = BaseCustomEvent.discriminator('D',
           DiscCustomEventSchema);
         const ContainerSchema = new Schema({
           title: String,
-          events: [{ type: Schema.Types.ObjectId, ref: 'base-custom-event' }]
+          events: [{ type: Schema.Types.ObjectId, ref: 'Test' }]
         });
-        ContainerModel = db.model('container-event-model', ContainerSchema);
+        ContainerModel = db.model('Test1', ContainerSchema);
       });
 
       it('into non-discriminated arrays works', function() {
@@ -225,24 +224,24 @@ describe('model', function() {
                   // doesn't find anything since we're querying for an impression id
                   const query = ConversionEvent.find({ _id: impressionEvent._id });
                   assert.equal(query.op, 'find');
-                  assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
+                  assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'Conversion' });
                   query.exec(function(err, documents) {
                     assert.ifError(err);
                     assert.equal(documents.length, 0);
 
                     // now find one with no criteria given and ensure it gets added to _conditions
                     const query = ConversionEvent.find();
-                    assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
+                    assert.deepEqual(query._conditions, { __t: 'Conversion' });
                     assert.equal(query.op, 'find');
                     query.exec(function(err, documents) {
                       assert.ifError(err);
                       assert.equal(documents.length, 2);
 
                       assert.ok(documents[0] instanceof ConversionEvent);
-                      assert.equal(documents[0].__t, 'model-discriminator-querying-conversion');
+                      assert.equal(documents[0].__t, 'Conversion');
 
                       assert.ok(documents[1] instanceof ConversionEvent);
-                      assert.equal(documents[1].__t, 'model-discriminator-querying-conversion');
+                      assert.equal(documents[1].__t, 'Conversion');
 
                       done();
                     });
@@ -268,24 +267,24 @@ describe('model', function() {
               // doesn't find anything since we're querying for an impression id
               const query = ConversionEvent.find({ _id: impressionEvent._id }, fields);
               assert.equal(query.op, 'find');
-              assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
+              assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'Conversion' });
               query.exec(function(err, documents) {
                 assert.ifError(err);
                 assert.equal(documents.length, 0);
 
                 // now find one with no criteria given and ensure it gets added to _conditions
                 const query = ConversionEvent.find({}, fields);
-                assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
+                assert.deepEqual(query._conditions, { __t: 'Conversion' });
                 assert.equal(query.op, 'find');
                 query.exec(function(err, documents) {
                   assert.ifError(err);
                   assert.equal(documents.length, 2);
 
                   assert.ok(documents[0] instanceof ConversionEvent);
-                  assert.equal(documents[0].__t, 'model-discriminator-querying-conversion');
+                  assert.equal(documents[0].__t, 'Conversion');
 
                   assert.ok(documents[1] instanceof ConversionEvent);
-                  assert.equal(documents[1].__t, 'model-discriminator-querying-conversion');
+                  assert.equal(documents[1].__t, 'Conversion');
                   done();
                 });
               });
@@ -480,7 +479,7 @@ describe('model', function() {
             // doesn't find anything since we're querying for an impression id
             const query = ConversionEvent.findOne({ _id: impressionEvent._id });
             assert.equal(query.op, 'findOne');
-            assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
+            assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'Conversion' });
 
             query.exec(function(err, document) {
               assert.ifError(err);
@@ -489,12 +488,12 @@ describe('model', function() {
               // now find one with no criteria given and ensure it gets added to _conditions
               const query = ConversionEvent.findOne();
               assert.equal(query.op, 'findOne');
-              assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
+              assert.deepEqual(query._conditions, { __t: 'Conversion' });
 
               query.exec(function(err, document) {
                 assert.ifError(err);
                 assert.ok(document instanceof ConversionEvent);
-                assert.equal(document.__t, 'model-discriminator-querying-conversion');
+                assert.equal(document.__t, 'Conversion');
                 done();
               });
             });
@@ -513,7 +512,7 @@ describe('model', function() {
             // doesn't find anything since we're querying for an impression id
             const query = ConversionEvent.findOne({ _id: impressionEvent._id }, fields);
             assert.equal(query.op, 'findOne');
-            assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'model-discriminator-querying-conversion' });
+            assert.deepEqual(query._conditions, { _id: impressionEvent._id, __t: 'Conversion' });
 
             query.exec(function(err, document) {
               assert.ifError(err);
@@ -522,12 +521,12 @@ describe('model', function() {
               // now find one with no criteria given and ensure it gets added to _conditions
               const query = ConversionEvent.findOne({}, fields);
               assert.equal(query.op, 'findOne');
-              assert.deepEqual(query._conditions, { __t: 'model-discriminator-querying-conversion' });
+              assert.deepEqual(query._conditions, { __t: 'Conversion' });
 
               query.exec(function(err, document) {
                 assert.ifError(err);
                 assert.ok(document instanceof ConversionEvent);
-                assert.equal(document.__t, 'model-discriminator-querying-conversion');
+                assert.equal(document.__t, 'Conversion');
                 done();
               });
             });
@@ -573,7 +572,7 @@ describe('model', function() {
             conversionEvent.save(function(err) {
               assert.ifError(err);
               const query = ConversionEvent.findOneAndUpdate({ name: 'Impression event' }, { $set: { name: 'Impression event - updated' } });
-              assert.deepEqual(query._conditions, { name: 'Impression event', __t: 'model-discriminator-querying-conversion' });
+              assert.deepEqual(query._conditions, { name: 'Impression event', __t: 'Conversion' });
               query.exec(function(err, document) {
                 assert.ifError(err);
                 assert.equal(document, null);
@@ -596,7 +595,7 @@ describe('model', function() {
             conversionEvent.save(function(err) {
               assert.ifError(err);
               const query = ConversionEvent.findOneAndUpdate({ name: 'Conversion event' }, { $set: { name: 'Conversion event - updated' } }, { new: true });
-              assert.deepEqual(query._conditions, { name: 'Conversion event', __t: 'model-discriminator-querying-conversion' });
+              assert.deepEqual(query._conditions, { name: 'Conversion event', __t: 'Conversion' });
               query.exec(function(err, document) {
                 assert.ifError(err);
                 const expected = conversionEvent.toJSON();
@@ -642,15 +641,15 @@ describe('model', function() {
         const busSchema = new Schema({ speed: Number });
 
         const userSchema = new Schema({
-          vehicles: [{ type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationVehicle' }],
-          favoriteVehicle: { type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationVehicle' },
-          favoriteBus: { type: Schema.Types.ObjectId, ref: 'ModelDiscriminatorPopulationBus' }
+          vehicles: [{ type: Schema.Types.ObjectId, ref: 'Vehicle' }],
+          favoriteVehicle: { type: Schema.Types.ObjectId, ref: 'Vehicle' },
+          favoriteBus: { type: Schema.Types.ObjectId, ref: 'Bus' }
         });
 
-        const Vehicle = db.model('ModelDiscriminatorPopulationVehicle', vehicleSchema);
-        const Car = Vehicle.discriminator('ModelDiscriminatorPopulationCar', carSchema);
-        const Bus = Vehicle.discriminator('ModelDiscriminatorPopulationBus', busSchema);
-        const User = db.model('ModelDiscriminatorPopulationUser', userSchema);
+        const Vehicle = db.model('Vehicle', vehicleSchema);
+        const Car = Vehicle.discriminator('Car', carSchema);
+        const Bus = Vehicle.discriminator('Bus', busSchema);
+        const User = db.model('User', userSchema);
 
         Vehicle.create({}, function(err, vehicle) {
           assert.ifError(err);
@@ -667,11 +666,11 @@ describe('model', function() {
                     _id: user._id,
                     vehicles: [
                       { _id: vehicle._id, __v: 0 },
-                      { _id: car._id, speed: 160, __v: 0, __t: 'ModelDiscriminatorPopulationCar' },
-                      { _id: bus._id, speed: 80, __v: 0, __t: 'ModelDiscriminatorPopulationBus' }
+                      { _id: car._id, speed: 160, __v: 0, __t: 'Car' },
+                      { _id: bus._id, speed: 80, __v: 0, __t: 'Bus' }
                     ],
-                    favoriteVehicle: { _id: car._id, speed: 160, __v: 0, __t: 'ModelDiscriminatorPopulationCar' },
-                    favoriteBus: { _id: bus._id, speed: 80, __v: 0, __t: 'ModelDiscriminatorPopulationBus' }
+                    favoriteVehicle: { _id: car._id, speed: 160, __v: 0, __t: 'Car' },
+                    favoriteBus: { _id: bus._id, speed: 80, __v: 0, __t: 'Bus' }
                   };
 
                   assert.deepEqual(user.toJSON(), expected);
@@ -699,11 +698,11 @@ describe('model', function() {
         const vehicleSchema = new Schema({});
         const carSchema = new Schema({
           speed: Number,
-          garage: { type: Schema.Types.ObjectId, ref: 'gh2719PopulationGarage' }
+          garage: { type: Schema.Types.ObjectId, ref: 'Test' }
         });
         const busSchema = new Schema({
           speed: Number,
-          garage: { type: Schema.Types.ObjectId, ref: 'gh2719PopulationGarage' }
+          garage: { type: Schema.Types.ObjectId, ref: 'Test' }
         });
 
         const garageSchema = new Schema({
@@ -711,10 +710,10 @@ describe('model', function() {
           num_of_places: Number
         });
 
-        const Vehicle = db.model('gh2719PopulationVehicle', vehicleSchema);
-        const Car = Vehicle.discriminator('gh2719PopulationCar', carSchema);
-        const Bus = Vehicle.discriminator('gh2719PopulationBus', busSchema);
-        const Garage = db.model('gh2719PopulationGarage', garageSchema);
+        const Vehicle = db.model('Vehicle', vehicleSchema);
+        const Car = Vehicle.discriminator('Car', carSchema);
+        const Bus = Vehicle.discriminator('Bus', busSchema);
+        const Garage = db.model('Test', garageSchema);
 
         Garage.create({ name: 'My', num_of_places: 3 }, function(err, garage) {
           assert.ifError(err);
@@ -740,15 +739,15 @@ describe('model', function() {
         const vehicleSchema = new Schema({
           wheels: [{
             type: Schema.Types.ObjectId,
-            ref: 'gh4643'
+            ref: 'Test'
           }]
         });
         const wheelSchema = new Schema({ brand: String });
         const busSchema = new Schema({ speed: Number });
 
-        const Vehicle = db.model('gh4643_0', vehicleSchema);
-        const Bus = Vehicle.discriminator('gh4643_00', busSchema);
-        const Wheel = db.model('gh4643', wheelSchema);
+        const Vehicle = db.model('Vehicle', vehicleSchema);
+        const Bus = Vehicle.discriminator('Bus', busSchema);
+        const Wheel = db.model('Test', wheelSchema);
 
         Wheel.create({ brand: 'Rotiform' }, function(err, wheel) {
           assert.ifError(err);
@@ -782,15 +781,15 @@ describe('model', function() {
         const orgSchema = new BaseSchema({});
         const schoolSchema = new BaseSchema({ principal: String });
 
-        const Org = db.model('gh5613', orgSchema);
-        Org.discriminator('gh5613_0', schoolSchema);
+        const Org = db.model('Test', orgSchema);
+        Org.discriminator('D', schoolSchema);
 
         Org.create({ name: 'test' }, function(error, doc) {
           assert.ifError(error);
           assert.ok(!doc.__t);
-          Org.findByIdAndUpdate(doc._id, { __t: 'gh5613_0' }, { new: true }, function(error, doc) {
+          Org.findByIdAndUpdate(doc._id, { __t: 'D' }, { new: true }, function(error, doc) {
             assert.ifError(error);
-            assert.equal(doc.__t, 'gh5613_0');
+            assert.equal(doc.__t, 'D');
             done();
           });
         });
@@ -812,6 +811,7 @@ describe('model', function() {
         util.inherits(BaseSchema, Schema);
 
         const EventSchema = new BaseSchema({});
+        db.deleteModel(/Event/);
         const Event = db.model('Event', EventSchema);
 
         const TalkSchema = new BaseSchema({
@@ -861,13 +861,13 @@ describe('model', function() {
         const PeopleSchema = Schema({ job: String, name: String },
           { discriminatorKey: 'job' });
 
-        const People = db.model('gh8471_People', PeopleSchema);
+        const People = db.model('Person', PeopleSchema);
 
         const DesignerSchema = Schema({ badge: String });
-        const Designer = People.discriminator('gh8471_Designer', DesignerSchema, 'Designer');
+        const Designer = People.discriminator('Designer', DesignerSchema, 'Designer');
 
         const DeveloperSchema = Schema({ coffeeAmount: Number });
-        const Developer = People.discriminator('gh8471_Developer', DeveloperSchema, 'Developer');
+        const Developer = People.discriminator('Developer', DeveloperSchema, 'Developer');
 
         return co(function*() {
           yield Designer.create({
@@ -958,13 +958,13 @@ describe('model', function() {
             // aggregations with empty pipelines, but that are over
             // discriminators be executed
             assert.deepEqual(aggregate._pipeline, [
-              { $match: { __t: 'model-discriminator-querying-impression' } },
+              { $match: { __t: 'Impression' } },
               { $group: { _id: '$__t', count: { $sum: 1 } } }
             ]);
 
             assert.equal(result.length, 1);
             assert.deepEqual(result, [
-              { _id: 'model-discriminator-querying-impression', count: 2 }
+              { _id: 'Impression', count: 2 }
             ]);
             done();
           });
@@ -977,13 +977,13 @@ describe('model', function() {
             }
           });
 
-          const Base = db.model('gh4991', baseSchema);
+          const Base = db.model('Test', baseSchema);
           const discriminatorSchema = new mongoose.Schema({
             internal: {
               password: { type: String, select: false }
             }
           });
-          const Discriminator = Base.discriminator('gh4991_0',
+          const Discriminator = Base.discriminator('D',
             discriminatorSchema);
 
           const obj = {
@@ -1007,11 +1007,11 @@ describe('model', function() {
             array: [{ type: String }]
           });
 
-          const Base = db.model('gh4991_A', baseSchema);
+          const Base = db.model('Test', baseSchema);
           const discriminatorSchema = new mongoose.Schema({
             propB: { type: String }
           });
-          const Discriminator = Base.discriminator('gh4991_A1', discriminatorSchema);
+          const Discriminator = Base.discriminator('D', discriminatorSchema);
 
           const obj = { propA: 'Hi', propB: 'test', array: ['a', 'b'] };
           Discriminator.create(obj, function(error) {
@@ -1037,7 +1037,7 @@ describe('model', function() {
             // aggregations with empty pipelines, but that are over
             // discriminators be executed
             assert.deepEqual(aggregate._pipeline, [
-              { $match: { __t: 'model-discriminator-querying-impression', name: 'Test Event' } }
+              { $match: { __t: 'Impression', name: 'Test Event' } }
             ]);
 
             assert.equal(result.length, 1);
diff --git a/test/model.populate.divergent.test.js b/test/model.populate.divergent.test.js
index 488a633c99c..78450e8638e 100644
--- a/test/model.populate.divergent.test.js
+++ b/test/model.populate.divergent.test.js
@@ -8,11 +8,9 @@
 const start = require('./common');
 
 const assert = require('assert');
-const utils = require('../lib/utils');
 
 const mongoose = start.mongoose;
 const DivergentArrayError = mongoose.Error.DivergentArrayError;
-const random = utils.random;
 
 /**
  * Tests.
@@ -32,8 +30,8 @@ describe('model: populate: divergent arrays', function() {
 
   before(function(done) {
     db = start();
-    C = db.model('Child', { _id: Number, name: String }, 'child-' + random());
-    M = db.model('Parent', { array: { type: [{ type: Number, ref: 'Child' }] } }, 'parent-' + random());
+    C = db.model('Child', { _id: Number, name: String });
+    M = db.model('Parent', { array: { type: [{ type: Number, ref: 'Child' }] } });
 
     C.create(
       { _id: 0, name: 'zero' }
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5c3ce08acc1..c9e8104ca9b 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -222,7 +222,7 @@ describe('model: populate:', function() {
         }
       });
 
-      const messageSchema = new Schema({
+      const commentSchema = new Schema({
         message: String,
         author: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
         target: { type: mongoose.Schema.Types.ObjectId, ref: 'User' }
@@ -230,12 +230,12 @@ describe('model: populate:', function() {
 
       const Company = db.model('Company', companySchema);
       const User = db.model('User', userSchema);
-      const Message = db.model('Message', messageSchema);
+      const Comment = db.model('Comment', commentSchema);
 
       const company = new Company({ name: 'IniTech' });
       const user1 = new User({ name: 'Bill', company: company._id });
       const user2 = new User({ name: 'Peter', company: company._id });
-      const message = new Message({
+      const message = new Comment({
         message: 'Problems with TPS Report',
         author: user1._id,
         target: user2._id
@@ -253,7 +253,7 @@ describe('model: populate:', function() {
       });
 
       function next() {
-        Message.findOne({ _id: message._id }, function(error, message) {
+        Comment.findOne({ _id: message._id }, function(error, message) {
           assert.ifError(error);
           const options = {
             path: 'author target',
@@ -3077,11 +3077,11 @@ describe('model: populate:', function() {
         _id: Number,
         exercises: [String]
       });
-      const LessonSchema = new mongoose.Schema({
+      const VideoSchema = new mongoose.Schema({
         _id: String,
         url: String
       });
-      const StudyPlanSchema = new mongoose.Schema({
+      const ListSchema = new mongoose.Schema({
         parts: [
           {
             title: String,
@@ -3098,13 +3098,13 @@ describe('model: populate:', function() {
         ]
       });
 
-      const StudyPlan = db.model('StudyPlan', StudyPlanSchema);
+      const List = db.model('List', ListSchema);
       const Test = db.model('Test', TestSchema);
-      const Lesson = db.model('Lesson', LessonSchema);
+      const Video = db.model('Video', VideoSchema);
 
       const test = new Test({ _id: 123, exercises: ['t1', 't2'] });
-      const lesson = new Lesson({ _id: 'lesson', url: 'https://youtube.com' });
-      const studyPlan = new StudyPlan({
+      const lesson = new Video({ _id: 'lesson', url: 'https://youtube.com' });
+      const list = new List({
         parts: [
           {
             title: 'Study Plan 01',
@@ -3115,11 +3115,11 @@ describe('model: populate:', function() {
               },
               {
                 item: lesson._id,
-                kind: 'Lesson'
+                kind: 'Video'
               },
               {
                 item: lesson._id,
-                kind: 'Lesson'
+                kind: 'Video'
               }
             ]
           }
@@ -3127,8 +3127,8 @@ describe('model: populate:', function() {
       });
 
       return co(function*() {
-        yield [test.save(), lesson.save(), studyPlan.save()];
-        const doc = yield StudyPlan.findOne({}).populate('parts.contents.item');
+        yield [test.save(), lesson.save(), list.save()];
+        const doc = yield List.findOne({}).populate('parts.contents.item');
 
         assert.strictEqual(doc.parts[0].contents[0].item.exercises[0], 't1');
         assert.strictEqual(doc.parts[0].contents[1].item.url, 'https://youtube.com');
@@ -3186,7 +3186,7 @@ describe('model: populate:', function() {
         }]
       });
 
-      const Post = db.model('Post', PostSchema);
+      const Post = db.model('BlogPost', PostSchema);
       const User = db.model('User', UserSchema);
 
       const user = {
@@ -4565,7 +4565,7 @@ describe('model: populate:', function() {
           });
 
           ReportItemSchema.virtual('itemDetail', {
-            ref: 'Item',
+            ref: 'Child',
             localField: 'idItem',
             foreignField: '_id',
             justOne: true // here is the problem
@@ -4575,8 +4575,8 @@ describe('model: populate:', function() {
             _id: String
           });
 
-          const ReportModel = db.model('Test', ReportSchema);
-          const ItemModel = db.model('Item', ItemSchema);
+          const ReportModel = db.model('Parent', ReportSchema);
+          const ItemModel = db.model('Child', ItemSchema);
 
           yield ItemModel.create({ _id: 'foo' });
 
@@ -4641,11 +4641,11 @@ describe('model: populate:', function() {
         const UserSchema = new Schema({
           openId: String
         });
-        const TaskSchema = new Schema({
+        const CommentSchema = new Schema({
           openId: String
         });
 
-        TaskSchema.virtual('user', {
+        CommentSchema.virtual('user', {
           ref: 'User',
           localField: 'openId',
           foreignField: 'openId',
@@ -4653,13 +4653,13 @@ describe('model: populate:', function() {
         });
 
         const User = db.model('User', UserSchema);
-        const Task = db.model('Task', TaskSchema);
+        const Comment = db.model('Comment', CommentSchema);
 
         User.create({ openId: 'user1' }, { openId: 'user2' }, function(error) {
           assert.ifError(error);
-          Task.create({ openId: 'user1' }, { openId: 'user2' }, function(error) {
+          Comment.create({ openId: 'user1' }, { openId: 'user2' }, function(error) {
             assert.ifError(error);
-            Task.
+            Comment.
               find().
               sort({ openId: 1 }).
               populate('user').
@@ -5539,7 +5539,7 @@ describe('model: populate:', function() {
             required: true
           }
         });
-        const Field = db.model('Test', fieldSchema, 'fields');
+        const Field = db.model('Test', fieldSchema);
 
         const imageFieldSchema = new mongoose.Schema({
           value: {
@@ -5850,15 +5850,15 @@ describe('model: populate:', function() {
           parentId: mongoose.Schema.Types.ObjectId
         });
         childSchema.virtual('parent', {
-          ref: 'gh5240',
+          ref: 'Parent',
           localField: 'parentId',
           foreignField: '_id',
           justOne: true
         });
         const teamSchema = new Schema({ people: [childSchema] });
 
-        const Parent = db.model('gh5240', parentSchema);
-        const Team = db.model('gh5240_0', teamSchema);
+        const Parent = db.model('Parent', parentSchema);
+        const Team = db.model('Team', teamSchema);
 
         Parent.create({ name: 'Darth Vader' }).
           then(function(doc) {
@@ -5887,14 +5887,14 @@ describe('model: populate:', function() {
           name: String
         });
 
-        const Parent = db.model('gh5334_0', parentSchema);
-        const Child = db.model('gh5334', childSchema);
+        const Parent = db.model('Parent', parentSchema);
+        const Child = db.model('Child', childSchema);
 
         Child.create({ name: 'Luke' }, function(error, child) {
           assert.ifError(error);
           Parent.create({ name: 'Vader', child: child._id }, function(error) {
             assert.ifError(error);
-            Parent.find().populate({ path: 'child', model: 'gh5334' }).cursor().next(function(error, doc) {
+            Parent.find().populate({ path: 'child', model: 'Child' }).cursor().next(function(error, doc) {
               assert.ifError(error);
               assert.equal(doc.child.name, 'Luke');
               done();
@@ -5908,13 +5908,13 @@ describe('model: populate:', function() {
           _id: Number,
           name: String
         }, { versionKey: null });
-        const Ref = db.model('gh5468', refSchema);
+        const Ref = db.model('Test', refSchema);
 
         const testSchema = new mongoose.Schema({
           _id: Number,
-          prevnxt: [{ type: Number, ref: 'gh5468' }]
+          prevnxt: [{ type: Number, ref: 'Test' }]
         });
-        const Test = db.model('gh5468_0', testSchema);
+        const Test = db.model('Test1', testSchema);
 
         const docs = [1, 2, 3, 4, 5, 6].map(function(i) {
           return { _id: i };
@@ -5950,14 +5950,14 @@ describe('model: populate:', function() {
           parentId: mongoose.Schema.Types.ObjectId
         });
         childSchema.virtual('parent', {
-          ref: 'gh5311',
+          ref: 'Parent',
           localField: 'parentId',
           foreignField: '_id',
           justOne: true
         });
 
-        const Parent = db.model('gh5311', parentSchema);
-        const Child = db.model('gh5311_0', childSchema);
+        const Parent = db.model('Parent', parentSchema);
+        const Child = db.model('Child', childSchema);
 
         Parent.create({ name: 'Darth Vader' }).
           then(function(doc) {
@@ -5980,11 +5980,11 @@ describe('model: populate:', function() {
 
       it('empty virtual with Model.populate (gh-5331)', function(done) {
         const myModelSchema = new Schema({
-          virtualRefKey: { type: String, ref: 'gh5331' }
+          virtualRefKey: { type: String, ref: 'Test' }
         });
         myModelSchema.set('toJSON', { virtuals: true });
         myModelSchema.virtual('populatedVirtualRef', {
-          ref: 'gh5331',
+          ref: 'Test',
           localField: 'virtualRefKey',
           foreignField: 'handle'
         });
@@ -5993,8 +5993,8 @@ describe('model: populate:', function() {
           handle: String
         });
 
-        const MyModel = db.model('gh5331_0', myModelSchema);
-        db.model('gh5331', otherModelSchema);
+        const MyModel = db.model('Test', myModelSchema);
+        db.model('Test1', otherModelSchema);
 
         MyModel.create({ virtualRefKey: 'test' }, function(error, doc) {
           assert.ifError(error);
@@ -6012,14 +6012,14 @@ describe('model: populate:', function() {
           name: String
         });
 
-        const SomeModel = db.model('gh4715', someModelSchema);
+        const SomeModel = db.model('Test', someModelSchema);
 
         const schema0 = new mongoose.Schema({
           name1: String
         });
 
         schema0.virtual('detail', {
-          ref: 'gh4715',
+          ref: 'Test',
           localField: '_id',
           foreignField: '_id',
           justOne: true
@@ -6030,7 +6030,7 @@ describe('model: populate:', function() {
           obj: schema0
         });
 
-        const ModelMain = db.model('gh4715_0', schemaMain);
+        const ModelMain = db.model('Test1', schemaMain);
 
         ModelMain.create({ name: 'Test', obj: {} }).
           then(function(m) {
@@ -6047,7 +6047,7 @@ describe('model: populate:', function() {
       });
 
       it('populate with missing schema (gh-5364)', function(done) {
-        const Foo = db.model('gh5364', new mongoose.Schema({
+        const Foo = db.model('Test', new mongoose.Schema({
           bar: {
             type: mongoose.Schema.Types.ObjectId,
             ref: 'Bar'
@@ -6069,13 +6069,13 @@ describe('model: populate:', function() {
           name: String
         });
 
-        db.model('gh5460', refSchema);
+        db.model('Test', refSchema);
 
         const schema = new mongoose.Schema({
-          ref: { type: mongoose.Schema.Types.ObjectId, ref: 'gh5460' }
+          ref: { type: mongoose.Schema.Types.ObjectId, ref: 'Test' }
         });
 
-        const Model = db.model('gh5460_0', schema);
+        const Model = db.model('Test1', schema);
 
         const q = Model.find().read('secondaryPreferred').populate('ref');
         assert.equal(q._mongooseOptions.populate['ref'].options.readPreference.mode,
@@ -6091,7 +6091,7 @@ describe('model: populate:', function() {
             departments: [DepartmentSchema]
           });
 
-          let Company = db.model('gh6245', CompanySchema);
+          let Company = db.model('Company', CompanySchema);
           const company = new Company({
             name: 'Uber',
             departments: [{ name: 'Security' }, { name: 'Engineering' }]
@@ -6102,16 +6102,16 @@ describe('model: populate:', function() {
           const EmployeeSchema = new Schema({ name: String });
           DepartmentSchema = new Schema({
             name: String,
-            employees: [{ type: mongoose.Schema.Types.ObjectId, ref: 'gh6245' }]
+            employees: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Company' }]
           });
           CompanySchema = new Schema({
             name: String,
             departments: [DepartmentSchema]
           });
 
-          delete db.models['gh6245'];
-          const Employee = db.model('gh6245_0', EmployeeSchema);
-          Company = db.model('gh6245', CompanySchema);
+          delete db.models['Company'];
+          const Employee = db.model('Person', EmployeeSchema);
+          Company = db.model('Company', CompanySchema);
 
           let uber = yield Company.findOne({ name: 'Uber' });
           const kurt = yield Employee.create({ name: 'Kurt' });
@@ -6136,7 +6136,7 @@ describe('model: populate:', function() {
           active: Boolean
         });
 
-        const Band = db.model('gh5336', BandSchema);
+        const Band = db.model('Band', BandSchema);
 
         const PersonSchema = new mongoose.Schema({
           name: String,
@@ -6144,12 +6144,12 @@ describe('model: populate:', function() {
         });
 
         PersonSchema.virtual('bandDetails', {
-          ref: 'gh5336',
+          ref: 'Band',
           localField: 'bands',
           foreignField: 'name',
           justOne: false
         });
-        const Person = db.model('gh5336_0', PersonSchema);
+        const Person = db.model('Person', PersonSchema);
 
         const band = new Band({ name: 'The Beatles', active: false });
         const person = new Person({
@@ -6182,7 +6182,7 @@ describe('model: populate:', function() {
           active: Boolean
         });
 
-        const Band = db.model('gh5336_10', BandSchema);
+        const Band = db.model('Band', BandSchema);
 
         const PersonSchema = new mongoose.Schema({
           name: String,
@@ -6190,12 +6190,12 @@ describe('model: populate:', function() {
         });
 
         PersonSchema.virtual('bandDetails', {
-          ref: 'gh5336_10',
+          ref: 'Band',
           localField: 'bands',
           foreignField: 'name',
           justOne: true
         });
-        const Person = db.model('gh5336_11', PersonSchema);
+        const Person = db.model('Person', PersonSchema);
 
         const band = new Band({ name: 'The Beatles', active: false });
         const person = new Person({
@@ -6228,20 +6228,20 @@ describe('model: populate:', function() {
           parentId: mongoose.Schema.Types.ObjectId
         });
 
-        const Child = db.model('gh4959', childSchema);
+        const Child = db.model('Child', childSchema);
 
         const parentSchema = new mongoose.Schema({
           name: String
         });
 
         parentSchema.virtual('detail', {
-          ref: 'gh4959',
+          ref: 'Child',
           localField: '_id',
           foreignField: 'parentId',
           justOne: true
         });
 
-        const Parent = db.model('gh4959_0', parentSchema);
+        const Parent = db.model('Parent', parentSchema);
 
         Parent.create({ name: 'Test' }).
           then(function(m) {
@@ -6261,15 +6261,15 @@ describe('model: populate:', function() {
 
       it('does not set `populated()` until populate is done (gh-5564)', function() {
         const userSchema = new mongoose.Schema({});
-        const User = db.model('gh5564', userSchema);
+        const User = db.model('User', userSchema);
 
         const testSchema = new mongoose.Schema({
           users: [{
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh5564'
+            ref: 'User'
           }]
         });
-        const Test = db.model('gh5564_0', testSchema);
+        const Test = db.model('Test', testSchema);
 
         return User.create({}).
           then(function(user) {
@@ -6662,7 +6662,7 @@ describe('model: populate:', function() {
           const User = db.model('Test1', userSchema);
           const City = db.model('Test2', citySchema);
           const District = db.model('Test3', districtSchema);
-          const Post = db.model('Post', postSchema);
+          const Post = db.model('BlogPost', postSchema);
 
           const house = new House({ location: '123 abc st.' });
           const city = new City({ name: 'Some City' });
@@ -6790,7 +6790,7 @@ describe('model: populate:', function() {
         db.deleteModel(/.*/);
         const User = db.model('User', userSchema);
         const Teacher = db.model('Test', teachSchema);
-        const Post = db.model('Post', postSchema);
+        const Post = db.model('BlogPost', postSchema);
         const Comment = db.model('Comment', commentSchema);
 
         const users = [];
@@ -7301,7 +7301,7 @@ describe('model: populate:', function() {
       name: String
     });
 
-    const UserModel = db.model('User', userSchema, 'users');
+    const UserModel = db.model('User', userSchema);
 
     const eventSchema = new Schema({
       message: String
@@ -7498,18 +7498,18 @@ describe('model: populate:', function() {
 
   it('passes scope as Model instance (gh-6726)', function() {
     const otherSchema = new Schema({ name: String });
-    const Other = db.model('gh6726_Other', otherSchema);
+    const Other = db.model('Test1', otherSchema);
     const schema = new Schema({
       x: {
         type: Schema.Types.ObjectId,
-        ref: 'gh6726_Other',
+        ref: 'Test1',
         get: function(v) {
           assert.strictEqual(this.constructor.name, 'model');
           return v;
         }
       }
     });
-    const Test = db.model('gh6726_Test', schema);
+    const Test = db.model('Test', schema);
     const other = new Other({ name: 'Max' });
     const test = new Test({ x: other._id });
     return co(function*() {
@@ -7522,12 +7522,12 @@ describe('model: populate:', function() {
 
   it('respects schema array even if underlying doc doesnt use array (gh-6908)', function() {
     const jobSchema = new Schema({
-      company: [{ type: Schema.Types.ObjectId, ref: 'gh6908_Company' }]
+      company: [{ type: Schema.Types.ObjectId, ref: 'Company' }]
     });
-    const Job = db.model('gh6908_Job', jobSchema);
+    const Job = db.model('Test', jobSchema);
 
     const companySchema = new Schema({ name: String });
-    const Company = db.model('gh6908_Company', companySchema);
+    const Company = db.model('Company', companySchema);
 
     return co(function*() {
       const mdb = yield Company.create({ name: 'MongoDB' });
@@ -7602,7 +7602,7 @@ describe('model: populate:', function() {
 
     const Author = db.model('Author', authorSchema);
     const Comment = db.model('Comment', commentSchema);
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
 
     const authors = '123'.split('').map(n => {
       return new Author({ name: `author${n}` });
@@ -7699,7 +7699,7 @@ describe('model: populate:', function() {
       postId: { type: Schema.Types.ObjectId }
     });
 
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
     const Comment = db.model('Comment', commentSchema);
 
     return co(function*() {
@@ -7730,7 +7730,7 @@ describe('model: populate:', function() {
       text: String
     });
 
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
     const Comment = db.model('Comment', commentSchema);
 
     return co(function*() {
@@ -7830,47 +7830,47 @@ describe('model: populate:', function() {
   });
 
   it('multiple localFields and foreignFields (gh-5704)', function() {
-    const OrderSchema = new Schema({
+    const childSchema = new Schema({
       _id: Number,
       sourceId: Number
     });
-    const RefundSchema = new Schema({
+    const parentSchema = new Schema({
       _id: Number,
-      internalOrderId: Number,
-      sourceOrderId: Number
+      internalChildId: Number,
+      sourceChildId: Number
     });
-    RefundSchema.virtual('orders', {
-      ref: 'Order',
+    parentSchema.virtual('children', {
+      ref: 'Child',
       localField: function() {
-        return this.internalOrderId ? 'internalOrderId' : 'sourceOrderId';
+        return this.internalChildId ? 'internalChildId' : 'sourceChildId';
       },
       foreignField: function() {
-        return this.internalOrderId ? '_id' : 'sourceId';
+        return this.internalChildId ? '_id' : 'sourceId';
       }
     });
 
-    const Order = db.model('Order', OrderSchema);
-    const Refund = db.model('Test', RefundSchema);
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
-      yield Order.create([
+      yield Child.create([
         { _id: 1 },
         { _id: 99, sourceId: 2 }
       ]);
 
-      yield Refund.create([
-        { _id: 10, internalOrderId: 1 },
-        { _id: 11, sourceOrderId: 2 }
+      yield Parent.create([
+        { _id: 10, internalChildId: 1 },
+        { _id: 11, sourceChildId: 2 }
       ]);
 
-      let res = yield Refund.find().sort({ _id: 1 }).populate('orders');
+      let res = yield Parent.find().sort({ _id: 1 }).populate('children');
 
       res = res.map(doc => doc.toObject({ virtuals: true }));
-      assert.equal(res[0].orders.length, 1);
-      assert.strictEqual(res[0].orders[0]._id, 1);
+      assert.equal(res[0].children.length, 1);
+      assert.strictEqual(res[0].children[0]._id, 1);
 
-      assert.equal(res[1].orders.length, 1);
-      assert.strictEqual(res[1].orders[0]._id, 99);
+      assert.equal(res[1].children.length, 1);
+      assert.strictEqual(res[1].children[0]._id, 99);
     });
   });
 
@@ -7958,7 +7958,7 @@ describe('model: populate:', function() {
       user2: mongoose.ObjectId
     });
     postSchema.path('user2').ref(User);
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
 
     return co(function*() {
       const user = yield User.create({ name: 'val' });
@@ -8097,7 +8097,7 @@ describe('model: populate:', function() {
       },
       m: String
     });
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
 
     return co(function*() {
       const user = yield User1.create({ name: 'val' });
@@ -8124,7 +8124,7 @@ describe('model: populate:', function() {
       title: String
     });
 
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
 
     return co(function*() {
       const user = yield User.create({ name: 'val' });
@@ -8465,7 +8465,7 @@ describe('model: populate:', function() {
 
   it('handles refPath on discriminator when populating top-level model (gh-5109)', function() {
     const options = { discriminatorKey: 'kind' };
-    const Post = db.model('Post', new Schema({ time: Date, text: String }, options));
+    const Post = db.model('BlogPost', new Schema({ time: Date, text: String }, options));
 
     const MediaPost = Post.discriminator('Test', new Schema({
       media: { type: Schema.Types.ObjectId, refPath: 'mediaType' },
@@ -8506,7 +8506,7 @@ describe('model: populate:', function() {
 
     postSchema.virtual('mediaType').get(function() { return this._mediaType; });
 
-    const Post = db.model('Post', postSchema);
+    const Post = db.model('BlogPost', postSchema);
     const Image = db.model('Image', new Schema({ url: String }));
     const Video = db.model('Video', new Schema({ url: String, duration: Number }));
 
@@ -9149,7 +9149,7 @@ describe('model: populate:', function() {
 
   it('works when embedded discriminator array has populated path but not refPath (gh-8527)', function() {
     const Image = db.model('Image', Schema({ imageName: String }));
-    const Text = db.model('Text', Schema({ textName: String }));
+    const Video = db.model('Video', Schema({ videoName: String }));
     const ItemSchema = Schema({ objectType: String }, {
       discriminatorKey: 'objectType',
       _id: false
@@ -9172,20 +9172,20 @@ describe('model: populate:', function() {
 
     const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
     ExampleSchema.path('list').discriminator('Image', InternalItemSchemaGen());
-    ExampleSchema.path('list').discriminator('Text', InternalItemSchemaGen());
+    ExampleSchema.path('list').discriminator('Video', InternalItemSchemaGen());
     ExampleSchema.path('list').discriminator('ExternalSource', externalSchema);
     ExampleSchema.path('list').discriminator('NestedData', NestedDataSchema);
     const Example = db.model('Test', ExampleSchema);
 
     return co(function*() {
       const image1 = yield Image.create({ imageName: '01image' });
-      const text1 = yield Text.create({ textName: '01text' });
+      const video1 = yield Video.create({ videoName: '01video' });
 
       const example = yield Example.create({
         test: 'example',
         list: [
           { data: image1._id, objectType: 'Image' },
-          { data: text1._id, objectType: 'Text' },
+          { data: video1._id, objectType: 'Video' },
           { data: { sourceId: 123 }, objectType: 'ExternalSource' },
           { data: { title: 'test' }, objectType: 'NestedData' }
         ]
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 012da70d173..1f3e0c30106 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -16,22 +16,25 @@ describe('QueryCursor', function() {
   let db;
   let Model;
 
-  before(function(done) {
+  before(function() {
     db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => require('./util').clearTestData(db));
 
+  beforeEach(function() {
     const schema = new Schema({ name: String });
     schema.virtual('test').get(function() { return 'test'; });
 
-    Model = db.model('gh1907_0', schema);
+    Model = db.model('Test', schema);
 
-    Model.create({ name: 'Axl' }, { name: 'Slash' }, function(error) {
-      assert.ifError(error);
-      done();
-    });
-  });
-
-  after(function(done) {
-    db.close(done);
+    return Model.create({ name: 'Axl' }, { name: 'Slash' });
   });
 
   describe('#next()', function() {
@@ -81,7 +84,7 @@ describe('QueryCursor', function() {
         name: String,
         born: String
       });
-      const Person = db.model('Person4342', personSchema);
+      const Person = db.model('Person', personSchema);
       const people = [
         { name: 'Axl Rose', born: 'William Bruce Rose' },
         { name: 'Slash', born: 'Saul Hudson' }
@@ -108,14 +111,14 @@ describe('QueryCursor', function() {
     it('with populate', function(done) {
       const bandSchema = new Schema({
         name: String,
-        members: [{ type: mongoose.Schema.ObjectId, ref: 'Person1907' }]
+        members: [{ type: mongoose.Schema.ObjectId, ref: 'Person' }]
       });
       const personSchema = new Schema({
         name: String
       });
 
-      const Person = db.model('Person1907', personSchema);
-      const Band = db.model('Band1907', bandSchema);
+      const Person = db.model('Person', personSchema);
+      const Band = db.model('Band', bandSchema);
 
       const people = [
         { name: 'Axl Rose' },
@@ -181,7 +184,8 @@ describe('QueryCursor', function() {
         next();
       });
 
-      const Model = db.model('gh5096', schema);
+      db.deleteModel(/Test/);
+      const Model = db.model('Test', schema);
       Model.create({ name: 'Test' }, function(error) {
         assert.ifError(error);
         Model.find().cursor().next(function(error, doc) {
@@ -400,7 +404,7 @@ describe('QueryCursor', function() {
 
   it('handles non-boolean lean option (gh-7137)', function() {
     const schema = new Schema({ name: String });
-    const Model = db.model('gh7137', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.create({ name: 'test' });
@@ -420,7 +424,7 @@ describe('QueryCursor', function() {
       name: String
     });
 
-    const User = db.model('gh4814', userSchema);
+    const User = db.model('User', userSchema);
 
     const cursor = User.find().cursor().addCursorFlag('noCursorTimeout', true);
 
@@ -435,7 +439,7 @@ describe('QueryCursor', function() {
       name: String
     });
 
-    const User = db.model('gh4998', userSchema);
+    const User = db.model('User', userSchema);
     const users = [];
     for (let i = 0; i < 100; i++) {
       users.push({
@@ -478,7 +482,7 @@ describe('QueryCursor', function() {
 
   it('pulls schema-level readPreference (gh-8421)', function() {
     const read = 'secondaryPreferred';
-    const User = db.model('gh8421', Schema({ name: String }, { read }));
+    const User = db.model('User', Schema({ name: String }, { read }));
     const cursor = User.find().cursor();
 
     assert.equal(cursor.options.readPreference.mode, read);
@@ -486,7 +490,7 @@ describe('QueryCursor', function() {
 
   it('eachAsync() with parallel > numDocs (gh-8422)', function() {
     const schema = new mongoose.Schema({ name: String });
-    const Movie = db.model('gh8422', schema);
+    const Movie = db.model('Movie', schema);
 
     return co(function*() {
       yield Movie.create([
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index 89f46d1d11e..3dbf5e3471d 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -15,9 +15,17 @@ describe('query middleware', function() {
   let Author;
   let Publisher;
 
+  before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
   const initializeData = function(done) {
-    Author = db.model('gh-2138', schema, 'gh-2138');
-    Publisher = db.model('gh-2138-1', publisherSchema, 'gh-2138-1');
+    Author = db.model('Person', schema);
+    Publisher = db.model('Publisher', publisherSchema, 'Publisher');
 
     Author.deleteMany({}, function(error) {
       if (error) {
@@ -52,7 +60,7 @@ describe('query middleware', function() {
     schema = new Schema({
       title: String,
       author: String,
-      publisher: { type: Schema.ObjectId, ref: 'gh-2138-1' },
+      publisher: { type: Schema.ObjectId, ref: 'Publisher' },
       options: String
     });
 
@@ -60,14 +68,11 @@ describe('query middleware', function() {
       name: String
     });
 
-    db = start();
-
     done();
   });
 
-  afterEach(function(done) {
-    db.close(done);
-  });
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
 
   it('has a pre find hook', function(done) {
     let count = 0;
@@ -388,7 +393,7 @@ describe('query middleware', function() {
     });
 
     return co(function*() {
-      const Model = db.model('gh7195_deleteOne', schema);
+      const Model = db.model('Test', schema);
       yield Model.create([{ title: 'foo' }, { title: 'bar' }]);
 
       const res = yield Model.deleteOne();
@@ -415,7 +420,7 @@ describe('query middleware', function() {
     });
 
     return co(function*() {
-      const Model = db.model('gh7195_deleteMany', schema);
+      const Model = db.model('Test', schema);
       yield Model.create([{ title: 'foo' }, { title: 'bar' }]);
 
       yield Model.deleteMany();
@@ -442,7 +447,7 @@ describe('query middleware', function() {
     });
 
     return co(function*() {
-      const Model = db.model('gh7195_distinct', schema);
+      const Model = db.model('Test', schema);
       yield Model.create([{ title: 'foo' }, { title: 'bar' }, { title: 'bar' }]);
 
       const res = yield Model.distinct('title');
@@ -462,7 +467,7 @@ describe('query middleware', function() {
       next(new Error('woops'));
     });
 
-    const Book = db.model('gh2284', testSchema);
+    const Book = db.model('Test', testSchema);
 
     Book.on('index', function(error) {
       assert.ifError(error);
@@ -491,7 +496,7 @@ describe('query middleware', function() {
       next(error);
     });
 
-    const Test = db.model('gh4885', testSchema);
+    const Test = db.model('Test', testSchema);
 
     Test.create({}, function(error) {
       assert.ok(error);
@@ -562,7 +567,7 @@ describe('query middleware', function() {
       next(new Error('test2'));
     });
 
-    const Test = db.model('gh4927', schema);
+    const Test = db.model('Test', schema);
 
     Test.find().exec(function(error) {
       assert.equal(error.message, 'test2');
@@ -586,7 +591,7 @@ describe('query middleware', function() {
       next();
     });
 
-    const Test = db.model('gh5153', schema.clone());
+    const Test = db.model('Test', schema.clone());
 
     Test.find().exec(function(error) {
       assert.ifError(error);
@@ -605,7 +610,7 @@ describe('query middleware', function() {
       next();
     });
 
-    const Test = db.model('gh7418', schema);
+    const Test = db.model('Test', schema);
 
     return Test.updateOne({}, { name: 'bar' }).
       then(() => assert.equal(calledPost, 1));
diff --git a/test/query.test.js b/test/query.test.js
index 66c328c5e16..b3706609fd8 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1812,7 +1812,7 @@ describe('Query', function() {
     });
 
     it.skip('allows sort with count (gh-3914)', function(done) {
-      const Post = db.model('Post', {
+      const Post = db.model('BlogPost', {
         title: String
       });
 
@@ -1824,7 +1824,7 @@ describe('Query', function() {
     });
 
     it.skip('allows sort with select (gh-3914)', function(done) {
-      const Post = db.model('Post', {
+      const Post = db.model('BlogPost', {
         title: String
       });
 
@@ -1836,7 +1836,7 @@ describe('Query', function() {
     });
 
     it('handles nested $ (gh-3265)', function(done) {
-      const Post = db.model('Post', {
+      const Post = db.model('BlogPost', {
         title: String,
         answers: [{
           details: String,
@@ -3090,14 +3090,14 @@ describe('Query', function() {
       const schema = new Schema({
         other: {
           type: Schema.Types.ObjectId,
-          ref: 'Other'
+          ref: 'Test1'
         }
       });
       schema.pre('findOne', function() {
         assert.deepStrictEqual(this.getPopulatedPaths(), ['other']);
       });
 
-      const Other = db.model('Other', otherSchema);
+      const Other = db.model('Test1', otherSchema);
       const Test = db.model('Test', schema);
 
       const other = new Other({ name: 'one' });
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 8391587bfc6..9bd099061c1 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -28,6 +28,9 @@ describe('Map', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('validation', function() {
     const nestedValidateCalls = [];
     const validateCalls = [];
@@ -287,15 +290,15 @@ describe('Map', function() {
           type: Map,
           of: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'MapPopulateTest'
+            ref: 'Test'
           }
         }
       });
 
       const KeySchema = new mongoose.Schema({ key: String });
 
-      const User = db.model('MapPopulateTest_0', UserSchema);
-      const Key = db.model('MapPopulateTest', KeySchema);
+      const User = db.model('User', UserSchema);
+      const Key = db.model('Test', KeySchema);
 
       return co(function*() {
         const key = yield Key.create({ key: 'abc123' });
@@ -322,15 +325,15 @@ describe('Map', function() {
           type: Map,
           of: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'MapPopulateWildcardTest'
+            ref: 'Test'
           }
         }
       });
 
       const KeySchema = new mongoose.Schema({ key: String });
 
-      const User = db.model('MapPopulateWildcardTest_0', UserSchema);
-      const Key = db.model('MapPopulateWildcardTest', KeySchema);
+      const User = db.model('User', UserSchema);
+      const Key = db.model('Test', KeySchema);
 
       return co(function*() {
         const key = yield Key.create({ key: 'abc123' });
@@ -351,15 +354,15 @@ describe('Map', function() {
           type: Map,
           of: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'MapPopulateMapDocTest'
+            ref: 'Test'
           }
         }
       });
 
       const KeySchema = new mongoose.Schema({ key: String });
 
-      const User = db.model('MapPopulateMapDocTest_0', UserSchema);
-      const Key = db.model('MapPopulateMapDocTest', KeySchema);
+      const User = db.model('User', UserSchema);
+      const Key = db.model('Test', KeySchema);
 
       return co(function*() {
         const key = yield Key.create({ key: 'abc123' });
@@ -382,8 +385,8 @@ describe('Map', function() {
 
       const KeySchema = new mongoose.Schema({ key: String });
 
-      const User = db.model('gh6460_User', UserSchema);
-      const Key = db.model('gh6460_Key', KeySchema);
+      const User = db.model('User', UserSchema);
+      const Key = db.model('Test', KeySchema);
 
       return co(function*() {
         const key = yield Key.create({ key: 'abc123' });
@@ -401,17 +404,17 @@ describe('Map', function() {
     });
 
     it('handles setting populated path to doc and then saving (gh-7745)', function() {
-      const Scene = db.model('gh7745_Scene', new mongoose.Schema({
+      const Scene = db.model('Test', new mongoose.Schema({
         name: String
       }));
 
-      const Event = db.model('gh7745_Event', new mongoose.Schema({
+      const Event = db.model('Event', new mongoose.Schema({
         scenes: {
           type: Map,
           default: {},
           of: {
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh7745_Scene'
+            ref: 'Test'
           }
         }
       }));
@@ -437,9 +440,9 @@ describe('Map', function() {
       n: Number
     });
 
-    const Test = db.model('MapDiscrimTest', TestSchema);
+    const Test = db.model('Test', TestSchema);
 
-    const Disc = Test.discriminator('MapDiscrimTest_0', new mongoose.Schema({
+    const Disc = Test.discriminator('D', new mongoose.Schema({
       m: {
         type: Map,
         of: Number
@@ -478,7 +481,7 @@ describe('Map', function() {
       }
     }, { _id: false, id: false }));
 
-    const Department = db.model('MapEmbeddedDiscrimTest', DepartmentSchema);
+    const Department = db.model('Test', DepartmentSchema);
 
     return co(function*() {
       const dept = new Department({
@@ -519,7 +522,7 @@ describe('Map', function() {
       }
     });
 
-    const Test = db.model('gh6478', schema);
+    const Test = db.model('Test', schema);
     const test = new Test({
       str: {
         testing: '123'
@@ -544,11 +547,11 @@ describe('Map', function() {
   it('updating map doesnt crash (gh-6750)', function() {
     return co(function*() {
       const Schema = mongoose.Schema;
-      const User = db.model('gh6750_User', {
+      const User = db.model('User', {
         maps: { type: Map, of: String, default: {} }
       });
 
-      const Post = db.model('gh6750_Post', {
+      const Post = db.model('BlogPost', {
         user: { type: Schema.Types.ObjectId, ref: 'User' }
       });
 
@@ -585,7 +588,7 @@ describe('Map', function() {
         }
       });
 
-      const Test = db.model('gh6938', schema);
+      const Test = db.model('Test', schema);
       const test = new Test({ widgets: { one: { x: 'a' } } });
       test.widgets.set('two', { x: 'b' });
       test.widgets.set('three', { x: 'c', child: { y: 2018 } });
@@ -596,7 +599,7 @@ describe('Map', function() {
   });
 
   it('array of mixed maps (gh-6995)', function() {
-    const Model = db.model('gh6995', new Schema({ arr: [Map] }));
+    const Model = db.model('Test', new Schema({ arr: [Map] }));
 
     return Model.create({ arr: [{ a: 1 }] }).
       then(doc => {
@@ -626,7 +629,7 @@ describe('Map', function() {
       }
     });
 
-    const Parent = db.model('gh7272', ParentSchema);
+    const Parent = db.model('Parent', ParentSchema);
 
     return co(function*() {
       yield Parent.create({ children: { luke: { age: 30 } } });
@@ -650,7 +653,7 @@ describe('Map', function() {
       }
     });
 
-    const Parent = db.model('gh7321', parentSchema);
+    const Parent = db.model('Parent', parentSchema);
 
     return co(function*() {
       const first = yield Parent.create({
@@ -680,7 +683,7 @@ describe('Map', function() {
       }
     });
 
-    const GoodsInfo = db.model('gh7630', schema);
+    const GoodsInfo = db.model('Test', schema);
 
     let goodsInfo = new GoodsInfo();
     goodsInfo.describe = new Map();
@@ -711,7 +714,7 @@ describe('Map', function() {
         }
       }
     });
-    const Model = db.model('gh7447', schema);
+    const Model = db.model('Test', schema);
 
     const doc = new Model({ myMap: { foo: 'bar' } });
     assert.equal(calls.length, 0);
@@ -734,7 +737,7 @@ describe('Map', function() {
         }
       }
     });
-    const Model = db.model('gh7859', schema);
+    const Model = db.model('Test', schema);
 
     const doc = new Model({ myMap: { foo: {} } });
 
@@ -752,7 +755,7 @@ describe('Map', function() {
         of: childSchema
       }
     });
-    const Model = db.model('gh8357', schema.clone());
+    const Model = db.model('Test', schema.clone());
 
     const doc = new Model({ myMap: { foo: { name: 'bar' } } });
 
@@ -771,7 +774,7 @@ describe('Map', function() {
         }
       }
     });
-    const Model = db.model('gh8424', schema);
+    const Model = db.model('Test', schema);
 
     const doc = new Model({ myMap: { foo: { name: 'bar' } } });
 

From 490eea63261b11621caa1086260de9346a4ce636 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Mar 2020 22:31:21 -0400
Subject: [PATCH 0596/2348] test: clean up some test failures re: #8481

---
 test/aggregate.test.js | 14 ++++++++------
 test/model.test.js     |  2 +-
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 1ae26845c02..a1181aa959e 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -38,13 +38,15 @@ function setupData(db, callback) {
   ];
   const Employee = db.model('Employee');
 
-  emps.forEach(function(data) {
-    const emp = new Employee(data);
+  Employee.deleteMany({}, function() {
+    emps.forEach(function(data) {
+      const emp = new Employee(data);
 
-    emp.save(function() {
-      if (++saved === emps.length) {
-        callback();
-      }
+      emp.save(function() {
+        if (++saved === emps.length) {
+          callback();
+        }
+      });
     });
   });
 }
diff --git a/test/model.test.js b/test/model.test.js
index 7ab143ef8eb..20ec973e4c9 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5806,7 +5806,7 @@ describe('Model', function() {
       });
 
       const M1 = db.model('Test', s1);
-      const M2 = db.model('Test1', s2, 'tests');
+      const M2 = db.model('Test1', s2, M1.collection.name);
 
       M1.create({ array: {} }, function(err, doc) {
         assert.ifError(err);

From ceecfa43a5bbde8e02ea6fddb6c074723a9bccb4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 14:10:15 -0400
Subject: [PATCH 0597/2348] test(map): repro #8652

---
 test/types.map.test.js | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index 9bd099061c1..b34a5eefdb8 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -781,4 +781,40 @@ describe('Map', function() {
     assert.equal(doc.myMap.get('foo').name, 'bar');
     assert.ok(!doc.myMap.get('foo')._id);
   });
+
+  it('avoids marking path as modified if setting to same value (gh-8652)', function() {
+    const childSchema = mongoose.Schema({ name: String }, { _id: false });
+    const schema = mongoose.Schema({
+      numMap: {
+        type: Map,
+        of: Number
+      },
+      docMap: {
+        type: Map,
+        of: childSchema
+      }
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      yield Model.create({
+        numMap: {
+          answer: 42,
+          powerLevel: 9001
+        },
+        docMap: {
+          captain: { name: 'Jean-Luc Picard' },
+          firstOfficer: { name: 'Will Riker' }
+        }
+      });
+      const doc = yield Model.findOne();
+  
+      doc.numMap.set('answer', 42);
+      doc.numMap.set('powerLevel', 9001);
+      doc.docMap.set('captain', { name: 'Jean-Luc Picard' });
+      doc.docMap.set('firstOfficer', { name: 'Will Riker' });
+  
+      assert.deepEqual(doc.modifiedPaths(), []);
+    });
+  });
 });

From c2f54306b76000ea69a904baa757267f49c94a3c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 14:10:49 -0400
Subject: [PATCH 0598/2348] chore: package.json formatting

---
 package.json | 39 +++++++++++++++++++++++++++------------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/package.json b/package.json
index be06aaedd23..9f68f51a67f 100644
--- a/package.json
+++ b/package.json
@@ -132,23 +132,38 @@
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",
       "no-undef": "error",
-      "key-spacing": [2, {
-        "beforeColon": false,
-        "afterColon": true
-      }],
-      "comma-spacing": [2, {
-        "before": false,
-        "after": true
-      }],
+      "key-spacing": [
+        2,
+        {
+          "beforeColon": false,
+          "afterColon": true
+        }
+      ],
+      "comma-spacing": [
+        2,
+        {
+          "before": false,
+          "after": true
+        }
+      ],
       "array-bracket-spacing": 1,
-      "object-curly-spacing": [2, "always"],
-      "comma-dangle": [2, "never"],
+      "object-curly-spacing": [
+        2,
+        "always"
+      ],
+      "comma-dangle": [
+        2,
+        "never"
+      ],
       "no-unreachable": 2,
       "quotes": [
         "error",
         "single"
       ],
-      "quote-props": ["error", "as-needed"],
+      "quote-props": [
+        "error",
+        "as-needed"
+      ],
       "semi": "error",
       "space-before-blocks": "error",
       "space-before-function-paren": [
@@ -179,4 +194,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
\ No newline at end of file
+}

From bca57f7283f6c56de87b5526be388db85187c952 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 14:10:53 -0400
Subject: [PATCH 0599/2348] fix(map): avoid marking map as modified if setting
 `key` to the same value

Fix #8652
---
 lib/types/map.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/types/map.js b/lib/types/map.js
index a188b2f057d..dae044d1a97 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const Mixed = require('../schema/mixed');
+const deepEqual = require('../utils').deepEqual;
 const get = require('../helpers/get');
 const util = require('util');
 const specialProperties = require('../helpers/specialProperties');
@@ -56,6 +57,7 @@ class MongooseMap extends Map {
     const populated = this.$__parent != null && this.$__parent.$__ ?
       this.$__parent.populated(fullPath) || this.$__parent.populated(this.$__path) :
       null;
+    const priorVal = this.get(key);
 
     if (populated != null) {
       if (value.$__ == null) {
@@ -81,8 +83,9 @@ class MongooseMap extends Map {
       value.$basePath = this.$__path + '.' + key;
     }
 
-    if (this.$__parent != null && this.$__parent.$__) {
-      this.$__parent.markModified(this.$__path + '.' + key);
+    const parent = this.$__parent;
+    if (parent != null && parent.$__ != null && !deepEqual(value, priorVal)) {
+      parent.markModified(this.$__path + '.' + key);
     }
   }
 

From ae823abaff0eaa4421781ef104908e9ec2064d6b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 14:14:19 -0400
Subject: [PATCH 0600/2348] style: fix lint

---
 test/types.map.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index b34a5eefdb8..c5c1b5546a9 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -808,12 +808,12 @@ describe('Map', function() {
         }
       });
       const doc = yield Model.findOne();
-  
+
       doc.numMap.set('answer', 42);
       doc.numMap.set('powerLevel', 9001);
       doc.docMap.set('captain', { name: 'Jean-Luc Picard' });
       doc.docMap.set('firstOfficer', { name: 'Will Riker' });
-  
+
       assert.deepEqual(doc.modifiedPaths(), []);
     });
   });

From 778f5746ad500e907526ec8bfe0b857852b5226a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 14:18:06 -0400
Subject: [PATCH 0601/2348] test: drop indexes after tests to fix some issues
 with #8481

---
 test/util.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/util.js b/test/util.js
index 91d92951dde..37282ec0257 100644
--- a/test/util.js
+++ b/test/util.js
@@ -9,6 +9,7 @@ exports.clearTestData = function clearTestData(db) {
 
   for (const model of Object.keys(db.models)) {
     arr.push(db.models[model].deleteMany({}));
+    arr.push(db.models[model].collection.dropIndexes().catch(() => {}));
   }
 
   return Promise.all(arr);

From 9670bf46e76ac7f9c623686c3367748b8ac30326 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 15:10:30 -0400
Subject: [PATCH 0602/2348] test: fix some more tests re: #8481

---
 test/aggregate.test.js         |  68 ++++++-------
 test/document.modified.test.js | 172 +++++++++++++++------------------
 test/model.test.js             |   4 +-
 test/query.cursor.test.js      |  19 ++--
 4 files changed, 126 insertions(+), 137 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index a1181aa959e..a9a9bcf49ed 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -18,17 +18,15 @@ const Schema = mongoose.Schema;
  * Test data
  */
 
-const EmployeeSchema = new Schema({
-  name: String,
-  sal: Number,
-  dept: String,
-  customers: [String],
-  reportsTo: String
-});
-
-mongoose.model('Employee', EmployeeSchema);
-
 function setupData(db, callback) {
+  const EmployeeSchema = new Schema({
+    name: String,
+    sal: Number,
+    dept: String,
+    customers: [String],
+    reportsTo: String
+  });
+
   let saved = 0;
   const emps = [
     { name: 'Alice', sal: 18000, dept: 'sales', customers: ['Eve', 'Fred'] },
@@ -36,7 +34,7 @@ function setupData(db, callback) {
     { name: 'Carol', sal: 14000, dept: 'r&d', reportsTo: 'Bob' },
     { name: 'Dave', sal: 14500, dept: 'r&d', reportsTo: 'Carol' }
   ];
-  const Employee = db.model('Employee');
+  const Employee = db.model('Employee', EmployeeSchema);
 
   Employee.deleteMany({}, function() {
     emps.forEach(function(data) {
@@ -94,6 +92,10 @@ describe('aggregate: ', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+
+  afterEach(() => require('./util').clearTestData(db));
+
   describe('append', function() {
     it('(pipeline)', function(done) {
       const aggregate = new Aggregate();
@@ -616,7 +618,7 @@ describe('aggregate: ', function() {
   });
 
   describe('exec', function() {
-    before(function(done) {
+    beforeEach(function(done) {
       setupData(db, done);
     });
 
@@ -774,7 +776,7 @@ describe('aggregate: ', function() {
         aggregate.
           model(db.model('Employee')).
           graphLookup({
-            from: 'employees',
+            from: 'Employee',
             startWith: '$reportsTo',
             connectFromField: 'reportsTo',
             connectToField: 'name',
@@ -1001,7 +1003,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh5251', s);
+        const M = db.model('Test', s);
 
         M.aggregate([{ $match: { name: 'test' } }], function(error, res) {
           assert.ifError(error);
@@ -1019,7 +1021,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh7606', s);
+        const M = db.model('Test', s);
 
         return co(function*() {
           yield M.create([{ name: 'alpha' }, { name: 'Zeta' }]);
@@ -1039,7 +1041,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh8017', s);
+        const M = db.model('Test', s);
 
         return co(function*() {
           yield M.create([{ name: 'alpha' }, { name: 'Zeta' }]);
@@ -1060,7 +1062,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh5251_post', s);
+        const M = db.model('Test', s);
 
         M.aggregate([{ $match: { name: 'test' } }], function(error, res) {
           assert.ifError(error);
@@ -1080,7 +1082,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh5251_error_agg', s);
+        const M = db.model('Test', s);
 
         M.aggregate([{ $fakeStage: { name: 'test' } }], function(error, res) {
           assert.ok(error);
@@ -1105,7 +1107,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh5251_error', s);
+        const M = db.model('Test', s);
 
         M.aggregate([{ $match: { name: 'test' } }], function(error, res) {
           assert.ok(error);
@@ -1131,7 +1133,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh5251_cursor', s);
+        const M = db.model('Test', s);
 
         let numDocs = 0;
         M.
@@ -1163,7 +1165,7 @@ describe('aggregate: ', function() {
           next();
         });
 
-        const M = db.model('gh5887_cursor', s);
+        const M = db.model('Test', s);
 
         return M.aggregate([{ $match: { name: 'test' } }]).explain().
           then(() => {
@@ -1176,7 +1178,7 @@ describe('aggregate: ', function() {
 
     it('readPref from schema (gh-5522)', function(done) {
       const schema = new Schema({ name: String }, { read: 'secondary' });
-      const M = db.model('gh5522', schema);
+      const M = db.model('Test', schema);
       const a = M.aggregate();
       assert.equal(a.options.readPreference.mode, 'secondary');
 
@@ -1189,7 +1191,7 @@ describe('aggregate: ', function() {
   });
 
   it('cursor (gh-3160)', function() {
-    const MyModel = db.model('gh3160', { name: String });
+    const MyModel = db.model('Test', { name: String });
 
     return co(function * () {
       yield MyModel.create({ name: 'test' });
@@ -1205,7 +1207,7 @@ describe('aggregate: ', function() {
   });
 
   it('catch() (gh-7267)', function() {
-    const MyModel = db.model('gh7267', {});
+    const MyModel = db.model('Test', {});
 
     return co(function * () {
       const err = yield MyModel.aggregate([{ $group: { foo: 'bar' } }]).
@@ -1218,7 +1220,7 @@ describe('aggregate: ', function() {
   it('cursor() without options (gh-3855)', function(done) {
     const db = start();
 
-    const MyModel = db.model('gh3855', { name: String });
+    const MyModel = db.model('Test', { name: String });
 
     db.on('open', function() {
       const cursor = MyModel.
@@ -1231,7 +1233,7 @@ describe('aggregate: ', function() {
   });
 
   it('cursor() with useMongooseAggCursor (gh-5145)', function(done) {
-    const MyModel = db.model('gh5145', { name: String });
+    const MyModel = db.model('Test', { name: String });
 
     const cursor = MyModel.
       aggregate([{ $match: { name: 'test' } }]).
@@ -1243,7 +1245,7 @@ describe('aggregate: ', function() {
   });
 
   it('cursor() with useMongooseAggCursor works (gh-5145) (gh-5394)', function(done) {
-    const MyModel = db.model('gh5394', { name: String });
+    const MyModel = db.model('Test', { name: String });
 
     MyModel.create({ name: 'test' }, function(error) {
       assert.ifError(error);
@@ -1265,7 +1267,7 @@ describe('aggregate: ', function() {
   });
 
   it('cursor() eachAsync (gh-4300)', function(done) {
-    const MyModel = db.model('gh4300', { name: String });
+    const MyModel = db.model('Test', { name: String });
 
     let cur = 0;
     const expectedNames = ['Axl', 'Slash'];
@@ -1294,7 +1296,7 @@ describe('aggregate: ', function() {
   });
 
   it('cursor() eachAsync with options (parallel)', function(done) {
-    const MyModel = db.model('gh-6168', { name: String });
+    const MyModel = db.model('Test', { name: String });
 
     const names = [];
     const startedAt = [];
@@ -1327,7 +1329,7 @@ describe('aggregate: ', function() {
   });
 
   it('ability to add noCursorTimeout option (gh-4241)', function(done) {
-    const MyModel = db.model('gh4241', {
+    const MyModel = db.model('Test', {
       name: String
     });
 
@@ -1344,7 +1346,7 @@ describe('aggregate: ', function() {
   });
 
   it('query by document (gh-4866)', function(done) {
-    const MyModel = db.model('gh4866', {
+    const MyModel = db.model('Test', {
       name: String
     });
 
@@ -1359,7 +1361,7 @@ describe('aggregate: ', function() {
   it('sort by text score (gh-5258)', function(done) {
     const mySchema = new Schema({ test: String });
     mySchema.index({ test: 'text' });
-    const M = db.model('gh5258', mySchema);
+    const M = db.model('Test', mySchema);
 
     M.on('index', function(error) {
       assert.ifError(error);
@@ -1388,7 +1390,7 @@ describe('aggregate: ', function() {
     it('adds hint option', function(done) {
       const mySchema = new Schema({ name: String, qty: Number });
       mySchema.index({ qty: -1, name: -1 });
-      const M = db.model('gh6251', mySchema);
+      const M = db.model('Test', mySchema);
       M.on('index', function(error) {
         assert.ifError(error);
         const docs = [
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index dd33084165f..56800d8b869 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -14,83 +14,81 @@ const Schema = mongoose.Schema;
 const ObjectId = Schema.ObjectId;
 const DocumentObjectId = mongoose.Types.ObjectId;
 
-/**
- * Setup.
- */
-
-const Comments = new Schema;
-
-Comments.add({
-  title: String,
-  date: Date,
-  body: String,
-  comments: [Comments]
-});
-
-const BlogPost = new Schema({
-  title: String,
-  author: String,
-  slug: String,
-  date: Date,
-  meta: {
-    date: Date,
-    visitors: Number
-  },
-  published: Boolean,
-  mixed: {},
-  numbers: [Number],
-  owners: [ObjectId],
-  comments: [Comments],
-  nested: { array: [Number] }
-});
+describe('document modified', function() {
+  let BlogPost;
+  let db;
 
-BlogPost
-  .path('title')
-  .get(function(v) {
-    if (v) {
-      return v.toUpperCase();
-    }
-    return v;
+  before(function() {
+    db = start();
   });
-
-BlogPost
-  .virtual('titleWithAuthor')
-  .get(function() {
-    return this.get('title') + ' by ' + this.get('author');
-  })
-  .set(function(val) {
-    const split = val.split(' by ');
-    this.set('title', split[0]);
-    this.set('author', split[1]);
+  after(function(done) {
+    db.close(done);
   });
 
-BlogPost.method('cool', function() {
-  return this;
-});
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
 
-BlogPost.static('woot', function() {
-  return this;
-});
+  beforeEach(function() {
+    const Comments = new Schema;
 
-const modelName = 'docuemnt.modified.blogpost';
-mongoose.model(modelName, BlogPost);
+    Comments.add({
+      title: String,
+      date: Date,
+      body: String,
+      comments: [Comments]
+    });
 
-const collection = 'blogposts_' + random();
+    const BlogPostSchema = new Schema({
+      title: String,
+      author: String,
+      slug: String,
+      date: Date,
+      meta: {
+        date: Date,
+        visitors: Number
+      },
+      published: Boolean,
+      mixed: {},
+      numbers: [Number],
+      owners: [ObjectId],
+      comments: [Comments],
+      nested: { array: [Number] }
+    });
 
-describe('document modified', function() {
-  let db;
+    BlogPostSchema
+      .path('title')
+      .get(function(v) {
+        if (v) {
+          return v.toUpperCase();
+        }
+        return v;
+      });
 
-  before(function() {
-    db = start();
-  });
+    BlogPostSchema
+      .virtual('titleWithAuthor')
+      .get(function() {
+        return this.get('title') + ' by ' + this.get('author');
+      })
+      .set(function(val) {
+        const split = val.split(' by ');
+        this.set('title', split[0]);
+        this.set('author', split[1]);
+      });
 
-  after(function(done) {
-    db.close(done);
+    BlogPostSchema.method('cool', function() {
+      return this;
+    });
+
+    BlogPostSchema.static('woot', function() {
+      return this;
+    });
+
+    BlogPost = db.model('BlogPost', BlogPostSchema); 
   });
 
   describe('modified states', function() {
     it('reset after save', function(done) {
-      const B = db.model(modelName, collection);
+      const B = BlogPost;
       const b = new B;
 
       b.numbers.push(3);
@@ -112,7 +110,6 @@ describe('document modified', function() {
     });
 
     it('of embedded docs reset after save', function(done) {
-      const BlogPost = db.model(modelName, collection);
       const post = new BlogPost({ title: 'hocus pocus' });
       post.comments.push({ title: 'Humpty Dumpty', comments: [{ title: 'nested' }] });
       post.save(function(err) {
@@ -127,7 +124,7 @@ describe('document modified', function() {
 
   describe('isDefault', function() {
     it('works', function(done) {
-      const MyModel = db.model('test',
+      const MyModel = db.model('Test',
         { name: { type: String, default: 'Val ' } });
       const m = new MyModel();
       assert.ok(m.$isDefault('name'));
@@ -137,7 +134,6 @@ describe('document modified', function() {
 
   describe('isModified', function() {
     it('should not throw with no argument', function(done) {
-      const BlogPost = db.model(modelName, collection);
       const post = new BlogPost;
 
       let threw = false;
@@ -152,7 +148,6 @@ describe('document modified', function() {
     });
 
     it('when modifying keys', function(done) {
-      const BlogPost = db.model(modelName, collection);
       const post = new BlogPost;
       post.init({
         title: 'Test',
@@ -173,8 +168,6 @@ describe('document modified', function() {
     });
 
     it('setting a key identically to its current value should not dirty the key', function(done) {
-      const BlogPost = db.model(modelName, collection);
-
       const post = new BlogPost;
       post.init({
         title: 'Test',
@@ -190,7 +183,6 @@ describe('document modified', function() {
 
     describe('on DocumentArray', function() {
       it('work', function(done) {
-        const BlogPost = db.model(modelName, collection);
         const post = new BlogPost();
         post.init({
           title: 'Test',
@@ -208,7 +200,6 @@ describe('document modified', function() {
         done();
       });
       it('with accessors', function(done) {
-        const BlogPost = db.model(modelName, collection);
         const post = new BlogPost();
         post.init({
           title: 'Test',
@@ -229,8 +220,6 @@ describe('document modified', function() {
 
     describe('on MongooseArray', function() {
       it('atomic methods', function(done) {
-        // COMPLETEME
-        const BlogPost = db.model(modelName, collection);
         const post = new BlogPost();
         assert.equal(post.isModified('owners'), false);
         post.get('owners').push(new DocumentObjectId);
@@ -238,8 +227,6 @@ describe('document modified', function() {
         done();
       });
       it('native methods', function(done) {
-        // COMPLETEME
-        const BlogPost = db.model(modelName, collection);
         const post = new BlogPost;
         assert.equal(post.isModified('owners'), false);
         done();
@@ -247,8 +234,6 @@ describe('document modified', function() {
     });
 
     it('on entire document', function(done) {
-      const BlogPost = db.model(modelName, collection);
-
       const doc = {
         title: 'Test',
         slug: 'test',
@@ -298,9 +283,9 @@ describe('document modified', function() {
 
     it('should let you set ref paths (gh-1530)', function(done) {
       const parentSchema = new Schema({
-        child: { type: Schema.Types.ObjectId, ref: 'gh-1530-2' }
+        child: { type: Schema.Types.ObjectId, ref: 'Child' }
       });
-      const Parent = db.model('gh-1530-1', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
       const childSchema = new Schema({
         name: String
       });
@@ -316,7 +301,7 @@ describe('document modified', function() {
         ++postCalls;
         next();
       });
-      const Child = db.model('gh-1530-2', childSchema);
+      const Child = db.model('Child', childSchema);
 
       const p = new Parent();
       const c = new Child({ name: 'Luke' });
@@ -383,8 +368,8 @@ describe('document modified', function() {
           children: [{ type: Schema.Types.ObjectId, ref: 'Child' }]
         });
 
-        const Parent = db.model('Parent', parentSchema, 'parents');
-        const Child = db.model('Child', parentSchema, 'children');
+        const Parent = db.model('Parent', parentSchema);
+        const Child = db.model('Child', parentSchema);
 
         const child = new Child({ name: 'Luke' });
         const p = new Parent({ name: 'Anakin', children: [child] });
@@ -394,7 +379,7 @@ describe('document modified', function() {
         done();
       });
 
-      it('setting nested arrays (gh-3721)', function(done) {
+      it('setting nested arrays (gh-3721)', function() {
         const userSchema = new Schema({
           name: { type: Schema.Types.String }
         });
@@ -407,7 +392,7 @@ describe('document modified', function() {
           }]
         });
 
-        const Account = db.model('Account', accountSchema);
+        const Account = db.model('Test', accountSchema);
 
         const user = new User({ name: 'Test' });
         const account = new Account({
@@ -417,26 +402,27 @@ describe('document modified', function() {
         });
 
         assert.ok(account.roles[0].users[0].isModified);
-        done();
+        return Promise.all([User.init(), Account.init()]);
       });
 
       it('with discriminators (gh-3575)', function(done) {
         const shapeSchema = new mongoose.Schema({}, { discriminatorKey: 'kind' });
 
-        const Shape = mongoose.model('gh3575', shapeSchema);
+        db.deleteModel(/Test/);
+        const Shape = db.model('Test', shapeSchema);
 
-        const Circle = Shape.discriminator('gh3575_0', new mongoose.Schema({
+        const Circle = Shape.discriminator('Circle', new mongoose.Schema({
           radius: { type: Number }
         }, { discriminatorKey: 'kind' }));
 
         const fooSchema = new mongoose.Schema({
           bars: [{
             type: mongoose.Schema.Types.ObjectId,
-            ref: 'gh3575'
+            ref: 'Test'
           }]
         });
 
-        const Foo = mongoose.model('Foo', fooSchema);
+        const Foo = db.model('Test1', fooSchema);
 
         const test = new Foo({});
         test.bars = [new Circle({}), new Circle({})];
@@ -452,7 +438,8 @@ describe('document modified', function() {
         const familySchema = new Schema({
           children: [{ name: { type: String, required: true } }]
         });
-        const Family = db.model('Family', familySchema);
+        db.deleteModel(/Test/);
+        const Family = db.model('Test', familySchema);
         Family.create({
           children: [
             { name: 'John' },
@@ -471,7 +458,7 @@ describe('document modified', function() {
     });
 
     it('should support setting mixed paths by string (gh-1418)', function(done) {
-      const BlogPost = db.model('1418', new Schema({ mixed: {} }));
+      const BlogPost = db.model('Test', new Schema({ mixed: {} }));
       let b = new BlogPost;
       b.init({ mixed: {} });
 
@@ -524,7 +511,7 @@ describe('document modified', function() {
         child: [childSchema]
       });
 
-      const Parent = db.model('gh-1754', parentSchema);
+      const Parent = db.model('Parent', parentSchema);
       Parent.create(
         { child: [{ name: 'Brian', grandChild: [{ name: 'Jake' }] }] },
         function(error, p) {
@@ -543,7 +530,6 @@ describe('document modified', function() {
     });
 
     it('should reset the modified state after calling unmarkModified', function(done) {
-      const BlogPost = db.model(modelName, collection);
       const b = new BlogPost();
       assert.equal(b.isModified('author'), false);
       b.author = 'foo';
diff --git a/test/model.test.js b/test/model.test.js
index 20ec973e4c9..723d7060cbb 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6094,8 +6094,8 @@ describe('Model', function() {
         yield Model.createCollection();
 
         // If the collection is not created, the following will throw
-        // MongoError: Collection [mongoose_test.create_xxx_users] not found.
-        yield db.collection('users').stats();
+        // MongoError: Collection [mongoose_test.User] not found.
+        yield db.collection('User').stats();
 
         yield Model.create([{ name: 'alpha' }, { name: 'Zeta' }]);
 
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 1f3e0c30106..17447929f43 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -176,7 +176,7 @@ describe('QueryCursor', function() {
       });
     });
 
-    it('with pre-find hooks (gh-5096)', function(done) {
+    it('with pre-find hooks (gh-5096)', function() {
       const schema = new Schema({ name: String });
       let called = 0;
       schema.pre('find', function(next) {
@@ -186,14 +186,14 @@ describe('QueryCursor', function() {
 
       db.deleteModel(/Test/);
       const Model = db.model('Test', schema);
-      Model.create({ name: 'Test' }, function(error) {
-        assert.ifError(error);
-        Model.find().cursor().next(function(error, doc) {
-          assert.ifError(error);
-          assert.equal(called, 1);
-          assert.equal(doc.name, 'Test');
-          done();
-        });
+
+      return co(function*() {
+        yield Model.deleteMany({});
+        yield Model.create({ name: 'Test' });
+
+        const doc = yield Model.find().cursor().next();
+        assert.equal(called, 1);
+        assert.equal(doc.name, 'Test');
       });
     });
   });
@@ -404,6 +404,7 @@ describe('QueryCursor', function() {
 
   it('handles non-boolean lean option (gh-7137)', function() {
     const schema = new Schema({ name: String });
+    db.deleteModel(/Test/);
     const Model = db.model('Test', schema);
 
     return co(function*() {

From 3885d8bdb14fae46c69788e0bea9ec44b0341c0f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 15:11:31 -0400
Subject: [PATCH 0603/2348] style: fix lint

---
 test/document.modified.test.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 56800d8b869..cf0a4e30cfd 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -7,7 +7,6 @@
 const start = require('./common');
 
 const assert = require('assert');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -83,7 +82,7 @@ describe('document modified', function() {
       return this;
     });
 
-    BlogPost = db.model('BlogPost', BlogPostSchema); 
+    BlogPost = db.model('BlogPost', BlogPostSchema);
   });
 
   describe('modified states', function() {

From f70f6cfe0f4690343184990b1da17b4fa88be362 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 15:15:50 -0400
Subject: [PATCH 0604/2348] test: fix tests re: #8481

---
 test/model.test.js        | 5 +++--
 test/query.cursor.test.js | 1 +
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 723d7060cbb..28b389c3cc4 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6092,16 +6092,17 @@ describe('Model', function() {
       return co(function*() {
         yield Model.collection.drop().catch(() => {});
         yield Model.createCollection();
+        const collectionName = Model.collection.name;
 
         // If the collection is not created, the following will throw
         // MongoError: Collection [mongoose_test.User] not found.
-        yield db.collection('User').stats();
+        yield db.collection(collectionName).stats();
 
         yield Model.create([{ name: 'alpha' }, { name: 'Zeta' }]);
 
         // Ensure that the default collation is set. Mongoose will set the
         // collation on the query itself (see gh-4839).
-        const res = yield db.collection('users').
+        const res = yield db.collection(collectionName).
           find({}).sort({ name: 1 }).toArray();
         assert.deepEqual(res.map(v => v.name), ['alpha', 'Zeta']);
       });
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 17447929f43..6f1741dc6e7 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -408,6 +408,7 @@ describe('QueryCursor', function() {
     const Model = db.model('Test', schema);
 
     return co(function*() {
+      yield Model.deleteMany({});
       yield Model.create({ name: 'test' });
 
       let doc;

From 2c8dd5122f6914e478b37884c4ee443aee45b5bf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 16:12:54 -0400
Subject: [PATCH 0605/2348] fix(connection): emit "disconnected" after losing
 connectivity to every member of a replica set with `useUnifiedTopology: true`

Fix #8643
---
 lib/connection.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index 513bbe1281e..003687bc525 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -736,6 +736,21 @@ Connection.prototype.openUri = function(uri, options, callback) {
             }
           });
         } else if (type.startsWith('ReplicaSet')) {
+          client.on('topologyDescriptionChanged', ev => {
+            // Emit disconnected if we've lost connectivity to _all_ servers
+            // in the replica set.
+            const description = ev.newDescription;
+            const servers = Array.from(ev.newDescription.servers.values());
+            const allServersDisconnected = description.type === 'ReplicaSetNoPrimary' &&
+              servers.reduce((cur, d) => cur || d.type === 'Unknown', false);
+            if (_this.readyState === STATES.connected && allServersDisconnected) {
+              // Implicitly emits 'disconnected'
+              _this.readyState = STATES.disconnected;
+            } else if (_this.readyState === STATES.disconnected && !allServersDisconnected) {
+              _handleReconnect();
+            }
+          });
+
           db.on('close', function() {
             const type = get(db, 's.topology.s.description.type', '');
             if (type !== 'ReplicaSetWithPrimary') {

From e58f6959e653b95f2069bf654847a04755833d05 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 17:15:24 -0400
Subject: [PATCH 0606/2348] test(updateValidators): repro #8659

---
 test/model.findOneAndUpdate.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 6a03b9fe9be..34c59a3290f 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -1409,6 +1409,21 @@ describe('model: findOneAndUpdate:', function() {
         });
     });
 
+    it('validators ignore paths underneath mixed (gh-8659)', function() {
+      let called = 0;
+      const s = new Schema({
+        n: {
+          type: 'Mixed',
+          validate: () => { ++called; return false; }
+        }
+      });
+      const Test = db.model('Test', s);
+
+      const updateOptions = { runValidators: true, upsert: true, new: true };
+      return Test.findOneAndUpdate({}, { 'n.test': 'foo' }, updateOptions).
+        then(() => assert.equal(called, 0));
+    });
+
     it('should work with arrays (gh-3035)', function(done) {
       const testSchema = new mongoose.Schema({
         id: String,

From 69b46531ed073813d2d02ecb29449daaba4817d3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 17:15:35 -0400
Subject: [PATCH 0607/2348] fix(updateValidators): don't run `Mixed` update
 validator on dotted path underneath mixed type

Fix #8659
---
 lib/helpers/updateValidators.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index 5f29e02ba68..852b9c15708 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -95,6 +95,9 @@ module.exports = function(query, schema, castedDoc, options, callback) {
     if (schemaPath == null) {
       return;
     }
+    if (schemaPath.instance === 'Mixed' && schemaPath.path !== i) {
+      return;
+    }
 
     if (v && Array.isArray(v.$in)) {
       v.$in.forEach((v, i) => {

From d44d123ebeac8584aa0d7131b15fb04d03f75b98 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 17:36:08 -0400
Subject: [PATCH 0608/2348] chore: quick fix re: #8659

---
 lib/helpers/updateValidators.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index 852b9c15708..bd2718d75de 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -95,7 +95,7 @@ module.exports = function(query, schema, castedDoc, options, callback) {
     if (schemaPath == null) {
       return;
     }
-    if (schemaPath.instance === 'Mixed' && schemaPath.path !== i) {
+    if (schemaPath.instance === 'Mixed' && schemaPath.path !== updates[i]) {
       return;
     }
 

From 24b6e1e0d6373ed4f13eef665989d12c881302da Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 18:02:45 -0400
Subject: [PATCH 0609/2348] test: clean up more unnecessary collections re:
 #8481

---
 test/document.strict.test.js       |  54 +++++--------
 test/document.test.js              |   1 -
 test/geojson.test.js               |   5 +-
 test/gh-1408.test.js               |   2 +-
 test/model.create.test.js          |   6 +-
 test/model.discriminator.test.js   |   4 +-
 test/model.field.selection.test.js |  54 ++++++-------
 test/model.geosearch.test.js       |  28 +++----
 test/model.querying.test.js        | 123 ++++++++++-------------------
 9 files changed, 106 insertions(+), 171 deletions(-)

diff --git a/test/document.strict.test.js b/test/document.strict.test.js
index 31c41ce2e8c..6edcee5bb22 100644
--- a/test/document.strict.test.js
+++ b/test/document.strict.test.js
@@ -24,10 +24,13 @@ describe('document: strict mode:', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   describe('should work', function() {
     let Lax, Strict;
 
-    before(function() {
+    beforeEach(function() {
       const raw = {
         ts: { type: Date, default: Date.now },
         content: String,
@@ -39,12 +42,8 @@ describe('document: strict mode:', function() {
       const lax = new Schema(raw, { strict: false, minimize: false });
       const strict = new Schema(raw);
 
-      Lax = db.model('Lax', lax);
-      Strict = db.model('Strict', strict);
-    });
-
-    after(function(done) {
-      db.close(done);
+      Lax = db.model('Test1', lax);
+      Strict = db.model('Test2', strict);
     });
 
     it('when creating models with non-strict schemas (gh-4274)', function(done) {
@@ -127,10 +126,6 @@ describe('document: strict mode:', function() {
         done();
       });
     });
-
-    after(function() {
-      db.close();
-    });
   });
 
   it('nested doc', function(done) {
@@ -142,8 +137,8 @@ describe('document: strict mode:', function() {
       name: { last: String }
     });
 
-    const Lax = db.model('NestedLax', lax, 'nestdoc' + random());
-    const Strict = db.model('NestedStrict', strict, 'nestdoc' + random());
+    const Lax = db.model('Test1', lax);
+    const Strict = db.model('Test2', strict);
 
     let l = new Lax;
     l.set('name', { last: 'goose', hack: 'xx' });
@@ -180,8 +175,8 @@ describe('document: strict mode:', function() {
       content: String
     });
 
-    const Lax = db.model('EmbeddedLax', new Schema({ dox: [lax] }, { strict: false }), 'embdoc' + random());
-    const Strict = db.model('EmbeddedStrict', new Schema({ dox: [strict] }, { strict: false }), 'embdoc' + random());
+    const Lax = db.model('Test1', new Schema({ dox: [lax] }, { strict: false }));
+    const Strict = db.model('Test2', new Schema({ dox: [strict] }, { strict: false }));
 
     let l = new Lax({ dox: [{ content: 'sample', rouge: 'data' }] });
     assert.equal(l.dox[0].$__.strictMode, false);
@@ -235,7 +230,7 @@ describe('document: strict mode:', function() {
         this.prop = v;
       });
 
-    const StrictModel = db.model('StrictVirtual', strictSchema);
+    const StrictModel = db.model('Test', strictSchema);
 
     const strictInstance = new StrictModel({
       email: 'hunter@skookum.com',
@@ -258,13 +253,11 @@ describe('document: strict mode:', function() {
   });
 
   it('can be overridden during set()', function(done) {
-    const db = start();
-
     const strict = new Schema({
       bool: Boolean
     });
 
-    const Strict = db.model('Strict', strict);
+    const Strict = db.model('Test', strict);
     const s = new Strict({ bool: true });
 
     // insert non-schema property
@@ -284,7 +277,7 @@ describe('document: strict mode:', function() {
             assert.ifError(err);
             assert.equal(doc._doc.bool, undefined);
             assert.equal(doc._doc.notInSchema, undefined);
-            db.close(done);
+            done();
           });
         });
       });
@@ -292,13 +285,11 @@ describe('document: strict mode:', function() {
   });
 
   it('can be overridden during update()', function(done) {
-    const db = start();
-
     const strict = new Schema({
       bool: Boolean
     });
 
-    const Strict = db.model('Strict', strict);
+    const Strict = db.model('Test', strict);
     const s = new Strict({ bool: true });
 
     // insert non-schema property
@@ -318,7 +309,6 @@ describe('document: strict mode:', function() {
             assert.ifError(err);
 
             Strict.findById(doc._id, function(err, doc) {
-              db.close();
               assert.ifError(err);
               assert.equal(doc._doc.bool, undefined);
               assert.equal(doc._doc.notInSchema, undefined);
@@ -330,13 +320,11 @@ describe('document: strict mode:', function() {
   });
 
   it('can be overwritten with findOneAndUpdate (gh-1967)', function(done) {
-    const db = start();
-
     const strict = new Schema({
       bool: Boolean
     });
 
-    const Strict = db.model('Strict', strict);
+    const Strict = db.model('Test', strict);
     const s = new Strict({ bool: true });
 
     // insert non-schema property
@@ -359,7 +347,7 @@ describe('document: strict mode:', function() {
               assert.ifError(err);
               assert.equal(doc._doc.bool, undefined);
               assert.equal(doc._doc.notInSchema, undefined);
-              db.close(done);
+              done();
             });
           });
       });
@@ -370,7 +358,7 @@ describe('document: strict mode:', function() {
     it('throws on set() of unknown property', function(done) {
       const schema = new Schema({ n: String, docs: [{ x: [{ y: String }] }] });
       schema.set('strict', 'throw');
-      const M = mongoose.model('throwStrictSet', schema, 'tss_' + random());
+      const M = db.model('Test', schema);
       const m = new M;
 
       const badField = /Field `[\w.]+` is not in schema/;
@@ -421,7 +409,7 @@ describe('document: strict mode:', function() {
       }, { strict: 'throw' });
 
       // Create the model
-      const Foo = mongoose.model('Foo1234', FooSchema);
+      const Foo = db.model('Test', FooSchema);
 
       assert.doesNotThrow(function() {
         new Foo({ name: 'bar' });
@@ -443,7 +431,7 @@ describe('document: strict mode:', function() {
       }, { strict: 'throw' });
 
       // Create the model
-      const Foo = mongoose.model('gh2665', FooSchema);
+      const Foo = db.model('Test', FooSchema);
 
       assert.doesNotThrow(function() {
         new Foo({ name: mongoose.Types.ObjectId(), father: { name: { full: 'bacon' } } });
@@ -459,7 +447,7 @@ describe('document: strict mode:', function() {
         }
       }, { strict: 'throw' });
 
-      const Test = mongoose.model('gh3735', schema);
+      const Test = db.model('Test', schema);
 
       assert.throws(function() {
         new Test({ resolved: 123 });
@@ -488,7 +476,7 @@ describe('document: strict mode:', function() {
       }
     });
 
-    const Model = db.model('gh7103', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc1 = new Model();
diff --git a/test/document.test.js b/test/document.test.js
index 507051ffd3a..34b4de73097 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -134,7 +134,6 @@ describe('document', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => util.clearTestData(db));
 
   describe('constructor', function() {
diff --git a/test/geojson.test.js b/test/geojson.test.js
index e54f6fd7609..8b7caadd84c 100644
--- a/test/geojson.test.js
+++ b/test/geojson.test.js
@@ -35,6 +35,9 @@ describe('geojson', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('driver query', function() {
     const City = db.model('City', new Schema({
       name: String,
@@ -66,7 +69,7 @@ describe('geojson', function() {
   it('within helper', function() {
     const denver = { type: 'Point', coordinates: [-104.9903, 39.7392] };
     // acquit:ignore:start
-    const City = db.model('City2', new Schema({
+    const City = db.model('City', new Schema({
       name: String,
       location: pointSchema
     }));
diff --git a/test/gh-1408.test.js b/test/gh-1408.test.js
index 324aca5d362..80146d23311 100644
--- a/test/gh-1408.test.js
+++ b/test/gh-1408.test.js
@@ -30,7 +30,7 @@ describe('documents should not be converted to _id (gh-1408)', function() {
       }
     });
 
-    const A = db.model('gh-1408', BrandSchema);
+    const A = db.model('Test', BrandSchema);
 
     const a = new A({
       settings: {
diff --git a/test/model.create.test.js b/test/model.create.test.js
index 567742615ea..a9a76ff62a3 100644
--- a/test/model.create.test.js
+++ b/test/model.create.test.js
@@ -28,7 +28,7 @@ describe('model', function() {
 
     before(function() {
       db = start();
-      B = db.model('model-create', schema, 'model-create-' + random());
+      B = db.model('Test', schema);
     });
 
     after(function(done) {
@@ -105,7 +105,9 @@ describe('model', function() {
       SchemaWithPreSaveHook.post('save', function() {
         countPost++;
       });
-      const MWPSH = db.model('mwpsh', SchemaWithPreSaveHook);
+
+      db.deleteModel(/Test/);
+      const MWPSH = db.model('Test', SchemaWithPreSaveHook);
       MWPSH.create([
         { preference: 'xx' },
         { preference: 'yy' },
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index d292e06edf7..674ef384fff 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -193,7 +193,7 @@ describe('model', function() {
     it('throws error when discriminator has mapped discriminator key in schema with discriminatorKey option set', function(done) {
       assert.throws(
           function() {
-            var Foo = db.model('Test1', new Schema({}, {discriminatorKey: '_type'}), 'model-discriminator-' + random());
+            var Foo = db.model('Test1', new Schema({}, {discriminatorKey: '_type'}));
             Foo.discriminator('Bar', new Schema({_type: String}));
           },
           /Discriminator "Bar" cannot have field with name "_type"/
@@ -202,7 +202,7 @@ describe('model', function() {
     });
 
     it('throws error when discriminator with taken name is added', function(done) {
-      var Foo = db.model('Test1', new Schema({}), 'model-discriminator-' + random());
+      var Foo = db.model('Test1', new Schema({}));
       Foo.discriminator('Token', new Schema());
       assert.throws(
           function() {
diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index 104d80ac3aa..4ef60e87052 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -8,7 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -18,11 +17,20 @@ const DocumentObjectId = mongoose.Types.ObjectId;
 describe('model field selection', function() {
   let Comments;
   let BlogPostB;
-  let modelName;
-  let collection;
   let db;
 
   before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -32,7 +40,7 @@ describe('model field selection', function() {
       comments: [Comments]
     });
 
-    BlogPostB = new Schema({
+    const BlogPostSchema = new Schema({
       title: String,
       author: String,
       slug: String,
@@ -51,18 +59,11 @@ describe('model field selection', function() {
       def: { type: String, default: 'kandinsky' }
     });
 
-    modelName = 'model.select.blogpost';
-    mongoose.model(modelName, BlogPostB);
-    collection = 'blogposts_' + random();
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
+    
+    BlogPostB = db.model('BlogPost', BlogPostSchema);
   });
 
   it('excluded fields should be undefined', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     const date = new Date;
 
     const doc = {
@@ -97,7 +98,6 @@ describe('model field selection', function() {
   });
 
   it('excluded fields should be undefined and defaults applied to other fields', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     const id = new DocumentObjectId;
     const date = new Date;
 
@@ -119,7 +119,6 @@ describe('model field selection', function() {
   });
 
   it('where subset of fields excludes _id', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     BlogPostB.create({ title: 'subset 1' }, function(err) {
       assert.ifError(err);
       BlogPostB.findOne({ title: 'subset 1' }, { title: 1, _id: 0 }, function(err, found) {
@@ -132,7 +131,6 @@ describe('model field selection', function() {
   });
 
   it('works with subset of fields, excluding _id', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     BlogPostB.create({ title: 'subset 1', author: 'me' }, function(err) {
       assert.ifError(err);
       BlogPostB.find({ title: 'subset 1' }, { title: 1, _id: 0 }, function(err, found) {
@@ -148,7 +146,7 @@ describe('model field selection', function() {
   });
 
   it('works with just _id and findOneAndUpdate (gh-3407)', function(done) {
-    const MyModel = db.model('gh3407', { test: { type: Number, default: 1 } });
+    const MyModel = db.model('Test', { test: { type: Number, default: 1 } });
 
     MyModel.collection.insertOne({}, function(error) {
       assert.ifError(error);
@@ -161,8 +159,6 @@ describe('model field selection', function() {
   });
 
   it('works with subset of fields excluding emebedded doc _id (gh-541)', function(done) {
-    const BlogPostB = db.model(modelName, collection);
-
     BlogPostB.create({ title: 'LOTR', comments: [{ title: ':)' }] }, function(err, created) {
       assert.ifError(err);
       BlogPostB.find({ _id: created }, { _id: 0, 'comments._id': 0 }, function(err, found) {
@@ -183,7 +179,6 @@ describe('model field selection', function() {
   });
 
   it('included fields should have defaults applied when no value exists in db (gh-870)', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     const id = new DocumentObjectId;
 
     BlogPostB.collection.insertOne(
@@ -205,8 +200,6 @@ describe('model field selection', function() {
   });
 
   it('including subdoc field excludes other subdoc fields (gh-1027)', function(done) {
-    const BlogPostB = db.model(modelName, collection);
-
     BlogPostB.create({ comments: [{ title: 'a' }, { title: 'b' }] }, function(err, doc) {
       assert.ifError(err);
 
@@ -228,8 +221,6 @@ describe('model field selection', function() {
   });
 
   it('excluding nested subdoc fields (gh-1027)', function(done) {
-    const BlogPostB = db.model(modelName, collection);
-
     BlogPostB.create({ title: 'top', comments: [{ title: 'a', body: 'body' }, { title: 'b', body: 'body', comments: [{ title: 'c' }] }] }, function(err, doc) {
       assert.ifError(err);
 
@@ -265,7 +256,7 @@ describe('model field selection', function() {
         ids: [{ type: Schema.ObjectId }]
       });
 
-      const B = db.model('gh-1091', postSchema);
+      const B = db.model('Test', postSchema);
       const _id1 = new mongoose.Types.ObjectId;
       const _id2 = new mongoose.Types.ObjectId;
 
@@ -304,7 +295,7 @@ describe('model field selection', function() {
         ids2: [{ type: Schema.ObjectId }]
       });
 
-      const B = db.model('gh-1334', postSchema);
+      const B = db.model('Test', postSchema);
       const _id1 = new mongoose.Types.ObjectId;
       const _id2 = new mongoose.Types.ObjectId;
 
@@ -349,7 +340,7 @@ describe('model field selection', function() {
         tags: [{ tag: String, count: 0 }]
       });
 
-      const Post = db.model('gh-2031', postSchema, 'gh-2031');
+      const Post = db.model('Test', postSchema);
       Post.create({ tags: [{ tag: 'bacon', count: 2 }, { tag: 'eggs', count: 3 }] }, function(error) {
         assert.ifError(error);
         Post.findOne({ 'tags.tag': 'eggs' }, { 'tags.$': 1 }, function(error, post) {
@@ -365,7 +356,7 @@ describe('model field selection', function() {
   });
 
   it('selecting an array of docs applies defaults properly (gh-1108)', function(done) {
-    const M = db.model(modelName, collection);
+    const M = BlogPostB;
 
     const m = new M({ title: '1108', comments: [{ body: 'yay' }] });
     m.comments[0].comments = undefined;
@@ -387,7 +378,7 @@ describe('model field selection', function() {
       name: String
     });
 
-    const MyModel = db.model('gh3903', schema);
+    const MyModel = db.model('Test', schema);
 
     MyModel.create({ name: 'val', length: 3 }, function(error) {
       assert.ifError(error);
@@ -419,7 +410,7 @@ describe('model field selection', function() {
       }
     });
 
-    const Route = db.model('Route' + random(), RouteSchema);
+    const Route = db.model('Test', RouteSchema);
 
     const item = {
       stations: {
@@ -480,7 +471,8 @@ describe('model field selection', function() {
       }
     });
 
-    const BlogPost = db.model('gh7159', BlogPostSchema);
+    db.deleteModel(/BlogPost/);
+    const BlogPost = db.model('BlogPost', BlogPostSchema);
 
     return co(function*() {
       yield BlogPost.create({
diff --git a/test/model.geosearch.test.js b/test/model.geosearch.test.js
index 5363b447d9a..ab7ba9944b5 100644
--- a/test/model.geosearch.test.js
+++ b/test/model.geosearch.test.js
@@ -3,17 +3,13 @@
 const start = require('./common');
 
 const assert = require('assert');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
 describe('model', function() {
   let db, schema;
-
-  function getModel(db) {
-    return db.model('GeoSearch', schema, 'geosearch-' + random());
-  }
+  let Geo;
 
   before(function() {
     schema = new Schema({
@@ -23,22 +19,23 @@ describe('model', function() {
     });
     schema.index({ pos: 'geoHaystack', type: 1 }, { bucketSize: 1 });
     db = start();
+
+    Geo = db.model('Test', schema);
   });
 
   after(function(done) {
     db.close(done);
   });
 
+  afterEach(() => Geo.deleteMany({}));
+
   describe('geoSearch', function() {
     this.timeout(process.env.TRAVIS ? 8000 : 4500);
 
     it('works', function(done) {
-      const Geo = getModel(db);
       assert.ok(Geo.geoSearch instanceof Function);
 
-      Geo.on('index', function(err) {
-        assert.ifError(err);
-
+      Geo.init(function() {
         const geos = [];
         geos[0] = new Geo({ pos: [10, 10], type: 'place' });
         geos[1] = new Geo({ pos: [15, 5], type: 'place' });
@@ -75,10 +72,9 @@ describe('model', function() {
       });
     });
     it('works with lean', function(done) {
-      const Geo = getModel(db);
       assert.ok(Geo.geoSearch instanceof Function);
 
-      Geo.on('index', function(err) {
+      Geo.init(function(err) {
         assert.ifError(err);
 
         const geos = [];
@@ -113,10 +109,9 @@ describe('model', function() {
       });
     });
     it('throws the correct error messages', function(done) {
-      const Geo = getModel(db);
       assert.ok(Geo.geoSearch instanceof Function);
 
-      Geo.on('index', function(err) {
+      Geo.init(function(err) {
         assert.ifError(err);
 
         const g = new Geo({ pos: [10, 10], type: 'place' });
@@ -146,9 +141,7 @@ describe('model', function() {
     });
 
     it('returns a promise (gh-1614)', function(done) {
-      const Geo = getModel(db);
-
-      Geo.on('index', function() {
+      Geo.init(function() {
         const prom = Geo.geoSearch({ type: 'place' }, { near: [9, 9], maxDistance: 5 });
         assert.ok(prom instanceof mongoose.Promise);
 
@@ -157,8 +150,7 @@ describe('model', function() {
     });
 
     it('allows not passing a callback (gh-1614)', function(done) {
-      const Geo = getModel(db);
-      Geo.on('index', function(err) {
+      Geo.init(function(err) {
         assert.ifError(err);
         const g = new Geo({ pos: [10, 10], type: 'place' });
         g.save(function(err) {
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 5d51a674610..010845b843f 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -22,7 +22,6 @@ const DocumentObjectId = mongoose.Types.ObjectId;
 describe('model: querying:', function() {
   let Comments;
   let BlogPostB;
-  let collection;
   let ModSchema;
   let geoSchema;
   let db;
@@ -89,11 +88,6 @@ describe('model: querying:', function() {
     db.close(done);
   });
 
-  beforeEach(function() {
-    // use different collection name in every test to avoid conflict (gh-6816)
-    collection = 'blogposts_' + random();
-  });
-
   it('find returns a Query', function(done) {
     // query
     assert.ok(BlogPostB.find({}) instanceof Query);
@@ -854,7 +848,7 @@ describe('model: querying:', function() {
         b: Schema.ObjectId
       });
 
-      const NE = db.model('NE_Test', schema, 'nes__' + random());
+      const NE = db.model('Test', schema);
 
       const id1 = new DocumentObjectId;
       const id2 = new DocumentObjectId;
@@ -872,10 +866,10 @@ describe('model: querying:', function() {
             assert.equal(nes1.length, 1);
 
             NE.find({ b: { $ne: [1] } }, function(err) {
-              assert.equal(err.message, 'Cast to ObjectId failed for value "[ 1 ]" at path "b" for model "NE_Test"');
+              assert.equal(err.message, 'Cast to ObjectId failed for value "[ 1 ]" at path "b" for model "Test"');
 
               NE.find({ b: { $ne: 4 } }, function(err) {
-                assert.equal(err.message, 'Cast to ObjectId failed for value "4" at path "b" for model "NE_Test"');
+                assert.equal(err.message, 'Cast to ObjectId failed for value "4" at path "b" for model "Test"');
 
                 NE.find({ b: id3, ids: { $ne: id4 } }, function(err, nes4) {
                   assert.ifError(err);
@@ -1588,8 +1582,7 @@ describe('model: querying:', function() {
   });
 
   it('by Date (gh-336)', function(done) {
-    // GH-336
-    const Test = db.model('TestDateQuery', new Schema({ date: Date }), 'datetest_' + random());
+    const Test = db.model('Test', new Schema({ date: Date }));
     const now = new Date;
 
     Test.create({ date: now }, { date: new Date(now - 10000) }, function(err) {
@@ -1604,7 +1597,7 @@ describe('model: querying:', function() {
 
   it('mixed types with $elemMatch (gh-591)', function(done) {
     const S = new Schema({ a: [{}], b: Number });
-    const M = db.model('QueryingMixedArrays', S, random());
+    const M = db.model('Test', S);
 
     const m = new M;
     m.a = [1, 2, { name: 'Frodo' }, 'IDK', { name: 100 }];
@@ -1638,7 +1631,7 @@ describe('model: querying:', function() {
       const SSchema = new Schema({ name: String });
       const PSchema = new Schema({ sub: [SSchema] });
 
-      const P = db.model('usingAllWithObjectIds', PSchema);
+      const P = db.model('Test', PSchema);
       const sub = [{ name: 'one' }, { name: 'two' }, { name: 'three' }];
 
       P.create({ sub: sub }, function(err, p) {
@@ -1671,7 +1664,7 @@ describe('model: querying:', function() {
       const SSchema = new Schema({ d: Date });
       const PSchema = new Schema({ sub: [SSchema] });
 
-      const P = db.model('usingAllWithDates', PSchema);
+      const P = db.model('Test', PSchema);
       const sub = [
         { d: new Date },
         { d: new Date(Date.now() - 10000) },
@@ -1718,7 +1711,7 @@ describe('model: querying:', function() {
 
       const next = function() {
         const schema = new Schema({ test: [String] });
-        const MyModel = db.model('gh3163', schema);
+        const MyModel = db.model('Test', schema);
 
         MyModel.create({ test: ['log1', 'log2'] }, function(error) {
           assert.ifError(error);
@@ -1778,7 +1771,7 @@ describe('model: querying:', function() {
     });
 
     it('works with nested query selectors gh-1884', function(done) {
-      const B = db.model('gh1884', { a: String, b: String }, 'gh1884');
+      const B = db.model('Test', { a: String, b: String });
 
       B.deleteOne({ $and: [{ a: 'coffee' }, { b: { $in: ['bacon', 'eggs'] } }] }, function(error) {
         assert.ifError(error);
@@ -1789,7 +1782,7 @@ describe('model: querying:', function() {
 
   it('works with different methods and query types', function(done) {
     const BufSchema = new Schema({ name: String, block: Buffer });
-    const Test = db.model('BufferTest', BufSchema, 'buffers');
+    const Test = db.model('Test', BufSchema);
 
     const docA = { name: 'A', block: Buffer.from('über') };
     const docB = { name: 'B', block: Buffer.from('buffer shtuffs are neat') };
@@ -1814,7 +1807,7 @@ describe('model: querying:', function() {
 
           Test.findOne({ block: /buffer/i }, function(err) {
             assert.equal(err.message, 'Cast to buffer failed for value ' +
-              '"/buffer/i" at path "block" for model "BufferTest"');
+              '"/buffer/i" at path "block" for model "Test"');
             Test.findOne({ block: [195, 188, 98, 101, 114] }, function(err, rb) {
               assert.ifError(err);
               assert.equal(rb.block.toString('utf8'), 'über');
@@ -1848,7 +1841,7 @@ describe('model: querying:', function() {
   it('with conditionals', function(done) {
     // $in $nin etc
     const BufSchema = new Schema({ name: String, block: Buffer });
-    const Test = db.model('Buffer2', BufSchema, 'buffer_' + random());
+    const Test = db.model('Test', BufSchema);
 
     const docA = { name: 'A', block: new MongooseBuffer([195, 188, 98, 101, 114]) }; // über
     const docB = { name: 'B', block: new MongooseBuffer('buffer shtuffs are neat') };
@@ -1963,7 +1956,7 @@ describe('model: querying:', function() {
 
   describe('2d', function() {
     it('$near (gh-309)', function(done) {
-      const Test = db.model('Geo1', geoSchema, 'geospatial' + random());
+      const Test = db.model('Test', geoSchema);
 
       let pending = 2;
 
@@ -1990,7 +1983,7 @@ describe('model: querying:', function() {
     });
 
     it('$within arrays (gh-586)', function(done) {
-      const Test = db.model('Geo2', geoSchema, collection + 'geospatial');
+      const Test = db.model('Test', geoSchema);
 
       let pending = 2;
 
@@ -2017,7 +2010,7 @@ describe('model: querying:', function() {
     });
 
     it('$nearSphere with arrays (gh-610)', function(done) {
-      const Test = db.model('Geo3', geoSchema, 'y' + random());
+      const Test = db.model('Test', geoSchema);
 
       let pending = 2;
 
@@ -2050,7 +2043,7 @@ describe('model: querying:', function() {
           coordinates: { type: [Number], index: '2dsphere' }
         }
       });
-      const Test = db.model('gh1874', geoSchema, 'gh1874');
+      const Test = db.model('Test', geoSchema);
 
       let pending = 2;
       const complete = function(err) {
@@ -2090,7 +2083,7 @@ describe('model: querying:', function() {
     });
 
     it('$maxDistance with arrays', function(done) {
-      const Test = db.model('Geo4', geoSchema, 'geo4');
+      const Test = db.model('Test', geoSchema);
 
       let pending = 2;
 
@@ -2172,7 +2165,7 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const Test = db.model('2dsphere-polygon', schema2dsphere, 'geospatial' + random());
+        const Test = db.model('Test', schema2dsphere);
 
         Test.on('index', function(err) {
           assert.ifError(err);
@@ -2205,7 +2198,7 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const Test = db.model('2dsphere-geo', geoSchema, 'geospatial' + random());
+        const Test = db.model('Test', geoSchema);
 
         Test.on('index', function(err) {
           assert.ifError(err);
@@ -2235,7 +2228,7 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const Test = db.model('2dsphere-geo-multi1', geoMultiSchema, 'geospatial' + random());
+        const Test = db.model('Test', geoMultiSchema);
 
         Test.create({
           geom: [{ type: 'LineString', coordinates: [[-178.0, 10.0], [178.0, 10.0]] },
@@ -2264,7 +2257,7 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const Test = db.model('2dsphere-geo-multi2', geoMultiSchema, 'geospatial' + random());
+        const Test = db.model('Test', geoMultiSchema);
 
         Test.create({
           geom: [{ type: 'Polygon', coordinates: [[[28.7, 41], [29.2, 40.9], [29.1, 41.3], [28.7, 41]]] },
@@ -2295,7 +2288,7 @@ describe('model: querying:', function() {
           return done();
         }
 
-        const Test = db.model('2dsphere-geo', geoSchema, 'geospatial' + random());
+        const Test = db.model('Test', geoSchema);
 
         Test.on('index', function(err) {
           assert.ifError(err);
@@ -2328,8 +2321,7 @@ describe('model: querying:', function() {
 
         const geoJSONSchema = new Schema({ loc: { type: { type: String }, coordinates: [Number] } });
         geoJSONSchema.index({ loc: '2dsphere' });
-        const name = 'geospatial' + random();
-        const Test = db.model('Geo1', geoJSONSchema, name);
+        const Test = db.model('Test', geoJSONSchema);
 
         let pending = 2;
 
@@ -2370,7 +2362,7 @@ describe('model: querying:', function() {
         }
 
         return co(function*() {
-          const Model = db.model('2dsphere-geo', schema2dsphere, 'geospatial' + random());
+          const Model = db.model('Test', schema2dsphere);
           yield Model.init();
           const model = new Model();
           model.loc = [1, 2];
@@ -2402,40 +2394,28 @@ describe('model: querying:', function() {
       if (!mongo24_or_greater) {
         return done();
       }
-      const schemas = [];
-      schemas[0] = new Schema({ t: { type: String, index: 'hashed' } });
-      schemas[1] = new Schema({ t: { type: String, index: 'hashed', sparse: true } });
-      schemas[2] = new Schema({ t: { type: String, index: { type: 'hashed', sparse: true } } });
 
-      let pending = schemas.length;
+      const schema = new Schema({ t: { type: String, index: 'hashed' } });
 
-      schemas.forEach(function(schema, i) {
-        const H = db.model('Hashed' + i, schema);
-        H.on('index', function(err) {
+      const H = db.model('Test', schema);
+      H.on('index', function(err) {
+        assert.ifError(err);
+        H.collection.getIndexes({ full: true }, function(err, indexes) {
           assert.ifError(err);
-          H.collection.getIndexes({ full: true }, function(err, indexes) {
-            assert.ifError(err);
 
-            const found = indexes.some(function(index) {
-              return index.key.t === 'hashed';
-            });
-            assert.ok(found);
+          const found = indexes.some(function(index) {
+            return index.key.t === 'hashed';
+          });
+          assert.ok(found);
 
-            H.create({ t: 'hashing' }, {}, function(err, doc1, doc2) {
-              assert.ifError(err);
-              assert.ok(doc1);
-              assert.ok(doc2);
-              complete();
-            });
+          H.create({ t: 'hashing' }, {}, function(err, doc1, doc2) {
+            assert.ifError(err);
+            assert.ok(doc1);
+            assert.ok(doc2);
+            done();
           });
         });
       });
-
-      function complete() {
-        if (--pending === 0) {
-          done();
-        }
-      }
     });
   });
 
@@ -2484,7 +2464,7 @@ describe('model: querying:', function() {
         subdoc: { title: String, num: Number }
       });
 
-      const M = mongoose.model('andor' + random(), sch);
+      const M = db.model('Test', sch);
 
       const cond = {
         $and: [
@@ -2506,7 +2486,7 @@ describe('model: querying:', function() {
         subdoc: { title: String, num: Number }
       });
 
-      const M = mongoose.model('andor' + random(), sch);
+      const M = db.model('Test', sch);
 
       const cond = {
         $and: [{ $or: [{ $and: [{ $or: [{ num: '12345' }, { 'subdoc.num': '56789' }] }] }] }]
@@ -2518,30 +2498,9 @@ describe('model: querying:', function() {
       done();
     });
 
-    it('test mongodb crash with invalid objectid string (gh-407)', function(done) {
-      const IndexedGuy = new mongoose.Schema({
-        name: { type: String }
-      });
-
-      const Guy = db.model('Guy', IndexedGuy);
-      Guy.find({
-        _id: {
-          $in: [
-            '4e0de2a6ee47bff98000e145',
-            '4e137bd81a6a8e00000007ac',
-            '',
-            '4e0e2ca0795666368603d974']
-        }
-      }, function(err) {
-        assert.equal(err.message,
-          'Cast to ObjectId failed for value "" at path "_id" for model "Guy"');
-        done();
-      });
-    });
-
     it('casts $elemMatch (gh-2199)', function(done) {
       const schema = new Schema({ dates: [Date] });
-      const Dates = db.model('Date', schema, 'dates');
+      const Dates = db.model('Test', schema);
 
       const array = ['2014-07-01T02:00:00.000Z', '2014-07-01T04:00:00.000Z'];
       Dates.create({ dates: array }, function(err) {

From 0e55fe0727cd862ad9a7a35c04578362a07a0536 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Mar 2020 18:05:48 -0400
Subject: [PATCH 0610/2348] style: fix lint

---
 test/document.strict.test.js       | 1 -
 test/model.create.test.js          | 1 -
 test/model.field.selection.test.js | 2 +-
 3 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/test/document.strict.test.js b/test/document.strict.test.js
index 6edcee5bb22..145af35c9e3 100644
--- a/test/document.strict.test.js
+++ b/test/document.strict.test.js
@@ -8,7 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.create.test.js b/test/model.create.test.js
index a9a76ff62a3..c6097f639de 100644
--- a/test/model.create.test.js
+++ b/test/model.create.test.js
@@ -7,7 +7,6 @@
 const start = require('./common');
 
 const assert = require('assert');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index 4ef60e87052..cca7e540dd4 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -59,7 +59,7 @@ describe('model field selection', function() {
       def: { type: String, default: 'kandinsky' }
     });
 
-    
+
     BlogPostB = db.model('BlogPost', BlogPostSchema);
   });
 

From 3a7cbb1002d20ec372573f9ea04e478511c8b433 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Mar 2020 10:34:26 -0400
Subject: [PATCH 0611/2348] chore: get rid of acorn devDependency re: security
 warning

---
 package.json         |  1 -
 test/webpack.test.js | 10 ----------
 2 files changed, 11 deletions(-)

diff --git a/package.json b/package.json
index 9f68f51a67f..eef4157e699 100644
--- a/package.json
+++ b/package.json
@@ -32,7 +32,6 @@
     "sift": "7.0.1"
   },
   "devDependencies": {
-    "acorn": "5.7.3",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
diff --git a/test/webpack.test.js b/test/webpack.test.js
index 831630cbb8b..f486de7a3a3 100644
--- a/test/webpack.test.js
+++ b/test/webpack.test.js
@@ -1,8 +1,6 @@
 'use strict';
 
-const acorn = require('acorn');
 const assert = require('assert');
-const fs = require('fs');
 const utils = require('../lib/utils');
 const semver = require('semver');
 
@@ -30,10 +28,6 @@ describe('webpack', function() {
       assert.ok(!bundleBuildStats.compilation.warnings.
         find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
 
-      const bundleContent = fs.readFileSync(`${__dirname}/files/dist/browser.umd.js`, 'utf8');
-
-      acorn.parse(bundleContent, { ecmaVersion: 5 });
-
       const baseConfig = require('../webpack.base.config.js');
       const config = Object.assign({}, baseConfig, {
         entry: ['./test/files/sample.js'],
@@ -52,10 +46,6 @@ describe('webpack', function() {
         assert.ok(!stats.compilation.warnings.
           find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
 
-        const content = fs.readFileSync(`${__dirname}/files/main.js`, 'utf8');
-
-        acorn.parse(content, { ecmaVersion: 5 });
-
         done();
       }));
       // acquit:ignore:end

From 0f1a80aac22713ad10fc519c602123596998c78c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Mar 2020 17:46:37 -0400
Subject: [PATCH 0612/2348] test: remove more unnecessary collections re: #8481

---
 test/model.aggregate.test.js     |   5 +-
 test/model.query.casting.test.js | 117 ++++++++++++++-----------------
 2 files changed, 53 insertions(+), 69 deletions(-)

diff --git a/test/model.aggregate.test.js b/test/model.aggregate.test.js
index 9df59434e4e..98dc7b1b239 100644
--- a/test/model.aggregate.test.js
+++ b/test/model.aggregate.test.js
@@ -23,9 +23,6 @@ const userSchema = new Schema({
   age: Number
 });
 
-const collection = 'aggregate_' + random();
-mongoose.model('Aggregate', userSchema);
-
 describe('model aggregate', function() {
   this.timeout(process.env.TRAVIS ? 8000 : 4500);
 
@@ -37,7 +34,7 @@ describe('model aggregate', function() {
 
   before(function(done) {
     db = start();
-    A = db.model('Aggregate', collection);
+    A = db.model('Test', userSchema);
 
     const authors = 'guillermo nathan tj damian marco'.split(' ');
     const num = 10;
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index 93b2b0f0c6c..c50af33ff55 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -19,13 +19,22 @@ const Schema = mongoose.Schema;
 describe('model query casting', function() {
   let Comments;
   let BlogPostB;
-  let collection;
   let geoSchemaArray;
   let geoSchemaObject;
-  let modelName;
   let db;
 
   before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -35,7 +44,7 @@ describe('model query casting', function() {
       comments: [Comments]
     });
 
-    BlogPostB = new Schema({
+    const BlogPostSchema = new Schema({
       title: { $type: String },
       author: String,
       slug: String,
@@ -54,23 +63,14 @@ describe('model query casting', function() {
       def: { $type: String, default: 'kandinsky' }
     }, { typeKey: '$type' });
 
-    modelName = 'model.query.casting.blogpost';
-    mongoose.model(modelName, BlogPostB);
-    collection = 'blogposts_' + random();
+    BlogPostB = db.model('BlogPost', BlogPostSchema);
 
     geoSchemaArray = new Schema({ loc: { type: [Number], index: '2d' } });
     geoSchemaObject = new Schema({ loc: { long: Number, lat: Number } });
     geoSchemaObject.index({ loc: '2d' });
-
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
   });
 
   it('works', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     const title = 'Loki ' + random();
 
     const post = new BlogPostB();
@@ -90,8 +90,6 @@ describe('model query casting', function() {
   });
 
   it('returns cast errors', function(done) {
-    const BlogPostB = db.model(modelName, collection);
-
     BlogPostB.find({ date: 'invalid date' }, function(err) {
       assert.ok(err instanceof Error);
       assert.ok(err instanceof CastError);
@@ -100,7 +98,6 @@ describe('model query casting', function() {
   });
 
   it('casts $modifiers', function(done) {
-    const BlogPostB = db.model(modelName, collection);
     const post = new BlogPostB({
       meta: {
         visitors: -75
@@ -124,8 +121,6 @@ describe('model query casting', function() {
   });
 
   it('casts $in values of arrays (gh-199)', function(done) {
-    const BlogPostB = db.model(modelName, collection);
-
     const post = new BlogPostB();
     const id = post._id.toString();
 
@@ -142,8 +137,6 @@ describe('model query casting', function() {
   });
 
   it('casts $in values of arrays with single item instead of array (jrl-3238)', function(done) {
-    const BlogPostB = db.model(modelName, collection);
-
     const post = new BlogPostB();
     const id = post._id.toString();
 
@@ -164,9 +157,7 @@ describe('model query casting', function() {
       num: Number
     });
 
-    mongoose.model('Nin', NinSchema);
-
-    const Nin = db.model('Nin', 'nins_' + random());
+    const Nin = db.model('Test', NinSchema);
 
     Nin.create({ num: 1 }, function(err) {
       assert.ifError(err);
@@ -185,7 +176,7 @@ describe('model query casting', function() {
   });
 
   it('works when finding by Date (gh-204)', function(done) {
-    const P = db.model(modelName, collection);
+    const P = BlogPostB;
 
     const post = new P;
 
@@ -212,7 +203,7 @@ describe('model query casting', function() {
   });
 
   it('works with $type matching', function(done) {
-    const B = db.model(modelName, collection);
+    const B = BlogPostB;
 
     B.find({ title: { $type: { x: 1 } } }, function(err) {
       assert.equal(err.message, '$type parameter must be number or string');
@@ -226,7 +217,7 @@ describe('model query casting', function() {
   });
 
   it('works when finding Boolean with $in (gh-998)', function(done) {
-    const B = db.model(modelName, collection);
+    const B = BlogPostB;
 
     const b = new B({ published: true });
     b.save(function(err) {
@@ -241,7 +232,7 @@ describe('model query casting', function() {
   });
 
   it('works when finding Boolean with $ne (gh-1093)', function(done) {
-    const B = db.model(modelName, collection + random());
+    const B = BlogPostB;
 
     const b = new B({ published: false });
     b.save(function(err) {
@@ -256,7 +247,7 @@ describe('model query casting', function() {
   });
 
   it('properly casts $and (gh-1180)', function(done) {
-    const B = db.model(modelName, collection + random());
+    const B = BlogPostB;
     const result = B.find({}).cast(B, { $and: [{ date: '1987-03-17T20:00:00.000Z' }, { _id: '000000000000000000000000' }] });
     assert.ok(result.$and[0].date instanceof Date);
     assert.ok(result.$and[1]._id instanceof DocumentObjectId);
@@ -267,7 +258,7 @@ describe('model query casting', function() {
     this.slow(60);
 
     it('with arrays', function(done) {
-      const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
+      const Test = db.model('Test', geoSchemaArray);
 
       Test.once('index', complete);
       Test.create({ loc: [10, 20] }, { loc: [40, 90] }, complete);
@@ -294,7 +285,7 @@ describe('model query casting', function() {
     });
 
     it('with objects', function(done) {
-      const Test = db.model('Geo5', geoSchemaObject, 'y' + random());
+      const Test = db.model('Test', geoSchemaObject);
 
       let pending = 2;
 
@@ -324,7 +315,7 @@ describe('model query casting', function() {
       const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
       geoSchemaObject.index({ 'loc.nested': '2d' });
 
-      const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
+      const Test = db.model('Test', geoSchemaObject);
 
       let pending = 2;
 
@@ -358,7 +349,7 @@ describe('model query casting', function() {
     this.slow(70);
 
     it('with arrays', function(done) {
-      const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
+      const Test = db.model('Test', geoSchemaArray);
 
       let pending = 2;
 
@@ -385,7 +376,7 @@ describe('model query casting', function() {
     });
 
     it('with objects', function(done) {
-      const Test = db.model('Geo5', geoSchemaObject, 'y' + random());
+      const Test = db.model('Test', geoSchemaObject);
 
       let pending = 2;
 
@@ -415,7 +406,7 @@ describe('model query casting', function() {
       const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
       geoSchemaObject.index({ 'loc.nested': '2d' });
 
-      const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
+      const Test = db.model('Test', geoSchemaObject);
 
       let pending = 2;
 
@@ -447,7 +438,7 @@ describe('model query casting', function() {
 
     describe('$centerSphere', function() {
       it('with arrays', function(done) {
-        const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
+        const Test = db.model('Test', geoSchemaArray);
 
         let pending = 2;
 
@@ -474,7 +465,7 @@ describe('model query casting', function() {
       });
 
       it('with objects', function(done) {
-        const Test = db.model('Geo5', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -504,7 +495,7 @@ describe('model query casting', function() {
         const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
         geoSchemaObject.index({ 'loc.nested': '2d' });
 
-        const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -533,7 +524,7 @@ describe('model query casting', function() {
 
     describe('$center', function() {
       it('with arrays', function(done) {
-        const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
+        const Test = db.model('Test', geoSchemaArray);
 
         let pending = 2;
 
@@ -560,7 +551,7 @@ describe('model query casting', function() {
       });
 
       it('with objects', function(done) {
-        const Test = db.model('Geo5', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -590,7 +581,7 @@ describe('model query casting', function() {
         const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
         geoSchemaObject.index({ 'loc.nested': '2d' });
 
-        const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -619,7 +610,7 @@ describe('model query casting', function() {
 
     describe('$polygon', function() {
       it('with arrays', function(done) {
-        const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
+        const Test = db.model('Test', geoSchemaArray);
 
         let pending = 2;
 
@@ -646,7 +637,7 @@ describe('model query casting', function() {
       });
 
       it('with objects', function(done) {
-        const Test = db.model('Geo5', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -676,7 +667,7 @@ describe('model query casting', function() {
         const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
         geoSchemaObject.index({ 'loc.nested': '2d' });
 
-        const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -705,7 +696,7 @@ describe('model query casting', function() {
 
     describe('$box', function() {
       it('with arrays', function(done) {
-        const Test = db.model('Geo4', geoSchemaArray, 'y' + random());
+        const Test = db.model('Test', geoSchemaArray);
 
         let pending = 2;
 
@@ -732,7 +723,7 @@ describe('model query casting', function() {
       });
 
       it('with objects', function(done) {
-        const Test = db.model('Geo5', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -762,7 +753,7 @@ describe('model query casting', function() {
         const geoSchemaObject = new Schema({ loc: { nested: { long: Number, lat: Number } } });
         geoSchemaObject.index({ 'loc.nested': '2d' });
 
-        const Test = db.model('Geo52', geoSchemaObject, 'y' + random());
+        const Test = db.model('Test', geoSchemaObject);
 
         let pending = 2;
 
@@ -797,7 +788,7 @@ describe('model query casting', function() {
         return 'img';
       };
 
-      const B = db.model(modelName, collection + random());
+      const B = BlogPostB;
       const result = B.find({}).cast(B, { tags: { $regex: /a/, $options: opts } });
 
       assert.equal(result.tags.$options, 'img');
@@ -808,7 +799,7 @@ describe('model query casting', function() {
         name: { type: String, uppercase: true }
       });
 
-      const Model = db.model('gh7800', testSchema);
+      const Model = db.model('Test', testSchema);
       const result = Model.find({}).cast(Model, { name: { $regex: /a/, $options: 'i' } });
 
       assert.equal(result.name.$options, 'i');
@@ -818,8 +809,6 @@ describe('model query casting', function() {
 
   describe('$elemMatch', function() {
     it('should cast String to ObjectId in $elemMatch', function(done) {
-      const BlogPostB = db.model(modelName, collection);
-
       const commentId = mongoose.Types.ObjectId(111);
 
       const post = new BlogPostB({ comments: [{ _id: commentId }] });
@@ -838,8 +827,6 @@ describe('model query casting', function() {
     });
 
     it('should cast String to ObjectId in $elemMatch inside $not', function(done) {
-      const BlogPostB = db.model(modelName, collection);
-
       const commentId = mongoose.Types.ObjectId(111);
 
       const post = new BlogPostB({ comments: [{ _id: commentId }] });
@@ -866,7 +853,7 @@ describe('model query casting', function() {
         children: [child]
       });
 
-      const Parent = db.model('gh3719-1', parent);
+      const Parent = db.model('Parent', parent);
 
       Parent.create({ children: [{ _id: 'foobar' }] }, function(error) {
         assert.ifError(error);
@@ -894,7 +881,7 @@ describe('model query casting', function() {
         children: [child]
       });
 
-      const Parent = db.model('gh3719-2', parent);
+      const Parent = db.model('Parent', parent);
 
       Parent.create({ children: [{ _id: 'foobar' }] }, function(error) {
         assert.ifError(error);
@@ -915,7 +902,7 @@ describe('model query casting', function() {
   });
 
   it('works with $all (gh-3394)', function(done) {
-    const MyModel = db.model('gh3394', { tags: [ObjectId] });
+    const MyModel = db.model('Test', { tags: [ObjectId] });
 
     const doc = {
       tags: ['00000000000000000000000a', '00000000000000000000000b']
@@ -933,7 +920,7 @@ describe('model query casting', function() {
   });
 
   it('date with $not + $type (gh-4632)', function(done) {
-    const MyModel = db.model('gh4632', { test: Date });
+    const MyModel = db.model('Test', { test: Date });
 
     MyModel.find({ test: { $not: { $type: 9 } } }, function(error) {
       assert.ifError(error);
@@ -960,7 +947,7 @@ describe('model query casting', function() {
     };
 
     const testSchema = new mongoose.Schema({ name: String, test: Point });
-    const Test = db.model('gh5126', testSchema);
+    const Test = db.model('Test', testSchema);
 
     const u = {
       $setOnInsert: {
@@ -992,7 +979,7 @@ describe('model query casting', function() {
       }
     });
 
-    const Test = db.model('gh-4569', testSchema);
+    const Test = db.model('Test', testSchema);
     Test.create({ name: 'val', num: 2.02 }).
       then(function() {
         assert.equal(contexts.length, 1);
@@ -1034,7 +1021,7 @@ describe('model query casting', function() {
       }
     });
 
-    const Test = db.model('gh5434', UserSchema);
+    const Test = db.model('Test', UserSchema);
 
     Test.find({ foo: '123' }).exec(function(error) {
       assert.ifError(error);
@@ -1067,7 +1054,7 @@ describe('model query casting', function() {
       }
     });
 
-    const Test = db.model('gh6157', UserSchema);
+    const Test = db.model('Test', UserSchema);
 
     Test.findOne({ foo: '123' }).exec(function(error) {
       assert.ifError(error);
@@ -1098,7 +1085,7 @@ describe('model query casting', function() {
       }
     });
 
-    const Test = db.model('gh5350', testSchema);
+    const Test = db.model('Test', testSchema);
     Test.create({ name: 'val', num: 2.02 }).
       then(function() {
         assert.equal(contexts.length, 1);
@@ -1115,7 +1102,7 @@ describe('model query casting', function() {
   });
 
   it('_id = 0 (gh-4610)', function(done) {
-    const MyModel = db.model('gh4610', { _id: Number });
+    const MyModel = db.model('Test', { _id: Number });
 
     MyModel.create({ _id: 0 }, function(error) {
       assert.ifError(error);
@@ -1131,7 +1118,7 @@ describe('model query casting', function() {
   it('converts to CastError (gh-6803)', function() {
     const membershipSchema = new Schema({ tier: String });
     const schema = new Schema({ membership: membershipSchema, name: String });
-    const Model = mongoose.model('gh6803', schema);
+    const Model = db.model('Test', schema);
 
     return Model.findOne({ membership: '12345' }).
       catch(error => {
@@ -1152,7 +1139,7 @@ describe('model query casting', function() {
 
     schema.index({ loc: '2dsphere' });
 
-    const MyModel = db.model('gh4197', schema);
+    const MyModel = db.model('Test', schema);
 
     MyModel.on('index', function(error) {
       assert.ifError(error);
@@ -1183,7 +1170,7 @@ describe('model query casting', function() {
   });
   it('array ops don\'t break with strict:false (gh-6952)', function(done) {
     const schema = new Schema({}, { strict: false });
-    const Test = db.model('gh6952', schema);
+    const Test = db.model('Test', schema);
     Test.create({ outerArray: [] })
       .then(function(created) {
         const toBePushedObj = { innerArray: ['onetwothree'] };

From 6065eff835e78fe649b6839f4f500fccbf90fd18 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Mar 2020 17:53:56 -0400
Subject: [PATCH 0613/2348] chore: release 5.9.5

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 3953fe8a6a3..b721ad0592c 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.9.5 / 2020-03-16
+==================
+ * fix: upgrade mongodb driver -> 3.5.5 #8667 #8664 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(connection): emit "disconnected" after losing connectivity to every member of a replica set with `useUnifiedTopology: true` #8643
+ * fix(array): allow calling `slice()` after `push()` #8668 #8655 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(map): avoid marking map as modified if setting `key` to the same value #8652
+ * fix(updateValidators): don't run `Mixed` update validator on dotted path underneath mixed type #8659
+ * fix(populate): ensure top-level `limit` applies if one document being populated has more than `limit` results #8657
+ * fix(populate): throw error if both `limit` and `perDocumentLimit` are set #8661 #8658 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(findOneAndUpdate): add a section about the `rawResult` option #8662
+ * docs(guide): add section about `loadClass()` #8623
+ * docs(query): improve `Query#populate()` example to clarify that `sort` doesn't affect the original result's order #8647
+
 5.9.4 / 2020-03-09
 ==================
  * fix(document): allow `new Model(doc)` to set immutable properties when doc is a mongoose document #8642
diff --git a/package.json b/package.json
index eef4157e699..48c5ee8969c 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.4",
+  "version": "5.9.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From f30617fa4eb336918b83c9a4c208082f514a0f6c Mon Sep 17 00:00:00 2001
From: Patrick Scott <patrickscott2013@gmail.com>
Date: Wed, 18 Mar 2020 00:47:48 -0400
Subject: [PATCH 0614/2348] Small typo fix in guide.pug

---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 7531b4e0e04..eed951366d7 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -127,7 +127,7 @@ block content
     ```
 
     When you create a new document with the automatically added
-    `_id` property, Mongoose createsa a new [`_id` of type ObjectId](https://masteringjs.io/tutorials/mongoose/objectid)
+    `_id` property, Mongoose creates a new [`_id` of type ObjectId](https://masteringjs.io/tutorials/mongoose/objectid)
     to your document.
 
     ```javascript

From fca1a473ec42e6f3d3664f0728fd350463386a14 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 20 Mar 2020 07:58:05 +0200
Subject: [PATCH 0615/2348] Fix broken HTML id references

---
 docs/deprecations.pug | 2 +-
 lib/connection.js     | 4 ++--
 lib/index.js          | 4 ++--
 lib/query.js          | 6 +++---
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/docs/deprecations.pug b/docs/deprecations.pug
index d847147db90..4c53a85c91f 100644
--- a/docs/deprecations.pug
+++ b/docs/deprecations.pug
@@ -78,7 +78,7 @@ block content
     by default you'll see one of the below deprecation warnings.
 
     ```
-    DeprecationWarning: Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the `useFindAndModify` option set to false are deprecated. See: https://mongoosejs.com/docs/deprecations.html#-findandmodify-
+    DeprecationWarning: Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the `useFindAndModify` option set to false are deprecated. See: https://mongoosejs.com/docs/deprecations.html#findandmodify
     DeprecationWarning: collection.findAndModify is deprecated. Use findOneAndUpdate, findOneAndReplace or findOneAndDelete instead.
     ```
 
diff --git a/lib/connection.js b/lib/connection.js
index 003687bc525..2bdfa698fe0 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -149,7 +149,7 @@ Connection.prototype.get = function(key) {
  * Supported options include:
  *
  * - `maxTimeMS`: Set [`maxTimeMS`](/docs/api.html#query_Query-maxTimeMS) for all queries on this connection.
- * - `useFindAndModify`: Set to `false` to work around the [`findAndModify()` deprecation warning](/docs/deprecations.html#-findandmodify-)
+ * - `useFindAndModify`: Set to `false` to work around the [`findAndModify()` deprecation warning](/docs/deprecations.html#findandmodify)
  *
  * ####Example:
  *
@@ -544,7 +544,7 @@ Connection.prototype.onOpen = function() {
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
  * @param {Boolean} [options.useNewUrlParser=false] False by default. Set to `true` to opt in to the MongoDB driver's new URL parser logic.
  * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to opt in to the MongoDB driver's replica set and sharded cluster monitoring engine.
- * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#-ensureindex-) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
+ * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
  * @param {Boolean} [options.useFindAndModify=true] True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
diff --git a/lib/index.js b/lib/index.js
index 4ce35c024a9..8db4da98e2d 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -251,7 +251,7 @@ Mongoose.prototype.get = Mongoose.prototype.set;
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
  * @param {Boolean} [options.useNewUrlParser=false] False by default. Set to `true` to make all connections set the `useNewUrlParser` option by default.
  * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to make all connections set the `useUnifiedTopology` option by default.
- * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#-ensureindex-) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
+ * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
  * @param {Boolean} [options.useFindAndModify=true] True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
@@ -311,7 +311,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
  * @param {Boolean} [options.useNewUrlParser=false] False by default. Set to `true` to opt in to the MongoDB driver's new URL parser logic.
  * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to opt in to the MongoDB driver's replica set and sharded cluster monitoring engine.
- * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#-ensureindex-) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
+ * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
  * @param {Boolean} [options.useFindAndModify=true] True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
diff --git a/lib/query.js b/lib/query.js
index 303983dfd36..681093e3cc7 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1833,7 +1833,7 @@ Query.prototype._unsetCastError = function _unsetCastError() {
  * - `lean`: if truthy, Mongoose will not [hydrate](/docs/api.html#model_Model.hydrate) any documents that are returned from this query. See [`Query.prototype.lean()`](/docs/api.html#query_Query-lean) for more information.
  * - `strict`: controls how Mongoose handles keys that aren't in the schema for updates. This option is `true` by default, which means Mongoose will silently strip any paths in the update that aren't in the schema. See the [`strict` mode docs](/docs/guide.html#strict) for more information.
  * - `strictQuery`: controls how Mongoose handles keys that aren't in the schema for the query `filter`. This option is `false` by default for backwards compatibility, which means Mongoose will allow `Model.find({ foo: 'bar' })` even if `foo` is not in the schema. See the [`strictQuery` docs](/docs/guide.html#strictQuery) for more information.
- * - `useFindAndModify`: used to work around the [`findAndModify()` deprecation warning](/docs/deprecations.html#-findandmodify-)
+ * - `useFindAndModify`: used to work around the [`findAndModify()` deprecation warning](/docs/deprecations.html#findandmodify)
  * - `omitUndefined`: delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * - `nearSphere`: use `$nearSphere` instead of `near()`. See the [`Query.prototype.nearSphere()` docs](/docs/api.html#query_Query-nearSphere)
  *
@@ -3613,7 +3613,7 @@ const _legacyFindAndModify = util.deprecate(function(filter, update, opts, cb) {
   collection.collection._findAndModify(filter, sort, update, opts, _cb);
 }, 'Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the ' +
   '`useFindAndModify` option set to false are deprecated. See: ' +
-  'https://mongoosejs.com/docs/deprecations.html#-findandmodify-');
+  'https://mongoosejs.com/docs/deprecations.html#findandmodify');
 
 /*!
  * Override mquery.prototype._mergeUpdate to handle mongoose objects in
@@ -3702,7 +3702,7 @@ function _updateThunk(op, callback) {
     if (op === 'updateOne' || op === 'updateMany') {
       return callback(new MongooseError('The MongoDB server disallows ' +
         'overwriting documents using `' + op + '`. See: ' +
-        'https://mongoosejs.com/docs/deprecations.html#-update-'));
+        'https://mongoosejs.com/docs/deprecations.html#update'));
     }
     this._update = new this.model(this._update, null, true);
   } else {

From 542a99b92477acb5fb6ca6d72198b5e43cd57dc2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 20 Mar 2020 10:17:14 +0200
Subject: [PATCH 0616/2348] Refactor #8331 test to prevent false positive

---
 test/model.test.js | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 28b389c3cc4..e0ea3df06fe 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5540,7 +5540,9 @@ describe('Model', function() {
 
         return co(function*() {
           const createdUser = yield User.create({ name: 'Hafez' });
-          let threw = false;
+
+          let err;
+
           try {
             yield User.bulkWrite([{
               updateOne: {
@@ -5548,17 +5550,16 @@ describe('Model', function() {
               }
             }]);
           }
-          catch (err) {
-            threw = true;
-            assert.equal(err.message, 'Must provide an update object.');
+          catch (_err) {
+            err = _err;
           }
-          finally {
-            assert.equal(threw, true);
 
-            const userAfterUpdate = yield User.findOne({ _id: createdUser._id });
+          assert.ok(err);
+          assert.equal(err.message, 'Must provide an update object.');
 
-            assert.equal(userAfterUpdate.name, 'Hafez', 'Document data is not wiped if no update object is provided.');
-          }
+          const userAfterUpdate = yield User.findOne({ _id: createdUser._id });
+
+          assert.equal(userAfterUpdate.name, 'Hafez', 'Document data is not wiped if no update object is provided.');
         });
       });
     });

From 0c526819695660c8e82806c297858ebfbfd11211 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Mar 2020 18:26:36 -0400
Subject: [PATCH 0617/2348] docs(populate): add note about `execPopulate()` to
 "populate an existing document" section

Fix #8671
---
 docs/populate.pug | 33 ++++++++++++++++++++++++++++-----
 1 file changed, 28 insertions(+), 5 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 1951402697d..de1383a28b0 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -357,17 +357,40 @@ block content
 
     <h3 id="populate_an_existing_mongoose_document"><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></h3>
 
-    If we have an existing mongoose document and want to populate some of its
-    paths, **mongoose >= 3.6** supports the
-    [document#populate()](./api.html#document_Document-populate) method.
+    If you have an existing mongoose document and want to populate some of its
+    paths, you can use the
+    [Document#populate()](./api.html#document_Document-populate) method.
+    Just make sure you call [`Document#execPopulate()`](/docs/api/document.html#document_Document-execPopulate)
+    to execute the `populate()`.
+
+    ```javascript
+    const person = await Person.findOne({ name: 'Ian Fleming' });
+    
+    person.populated('stories'); // null
+
+    // Call the `populate()` method on a document to populate a path.
+    // Need to call `execPopulate()` to actually execute the `populate()`.
+    await person.populate('stories').execPopulate();
+
+    person.populated('stories'); // Array of ObjectIds
+    person.stories[0].name; // 'Casino Royale'
+    ```
+
+    The `Document#populate()` method supports chaining, so you can chain
+    multiple `populate()` calls together.
+
+    ```javascript
+    await person.populate('stories').populate('fans').execPopulate();
+    person.populated('fans'); // Array of ObjectIds
+    ```
 
     <h3 id="populate_multiple_documents"><a href="#populate_multiple_documents">Populating multiple existing documents</a></h3>
 
     If we have one or many mongoose documents or even plain objects
     (_like [mapReduce](./api.html#model_Model.mapReduce) output_), we may
     populate them using the [Model.populate()](./api.html#model_Model.populate)
-    method available in **mongoose >= 3.6**. This is what `document#populate()`
-    and `query#populate()` use to populate documents.
+    method. This is what `Document#populate()`
+    and `Query#populate()` use to populate documents.
 
     <h3 id="deep-populate"><a href="#deep-populate">Populating across multiple levels</a></h3>
 

From 288892f306dd7c1dcf6fc428e42d70aedfb4b60e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Mar 2020 19:23:50 -0400
Subject: [PATCH 0618/2348] refactor: remove more unnecessary collections from
 model tests re: #8481

---
 test/model.discriminator.querying.test.js |   4 +-
 test/model.discriminator.test.js          |  23 ----
 test/model.findOneAndDelete.test.js       |  63 +++++-----
 test/model.findOneAndRemove.test.js       |  63 +++++-----
 test/model.findOneAndReplace.test.js      |  71 ++++++------
 test/model.findOneAndUpdate.test.js       | 135 ++++++++++------------
 test/model.hydrate.test.js                |   4 +-
 test/model.indexes.test.js                |  97 ++++++++--------
 test/model.middleware.test.js             |  29 ++---
 9 files changed, 223 insertions(+), 266 deletions(-)

diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 9b4d1c823b9..08954b5259c 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -818,13 +818,13 @@ describe('model', function() {
           pin: { type: String, required: true, index: { unique: true } },
           totalAttendees: { type: Number },
           speakers: [{ type: Schema.Types.ObjectId, ref: 'Speaker' }],
-          surveys: [{ type: Schema.Types.ObjectId, ref: 'Survey' }],
+          surveys: [{ type: Schema.Types.ObjectId, ref: 'Test' }],
           questions: [{ type: Schema.Types.ObjectId, ref: 'Question' }]
         });
 
         const Talk = Event.discriminator('Talk', TalkSchema);
 
-        const Survey = db.model('Survey', Schema({
+        const Survey = db.model('Test', Schema({
           name: String,
           date: Date
         }));
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 674ef384fff..1ebb9ee415b 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1319,29 +1319,6 @@ describe('model', function() {
 
       mongoose.deleteModel(/Model/);
     });
-
-    describe('does not have unintended side effects', function() {
-      // Delete every model
-      afterEach(function() { mongoose.deleteModel(/.+/); });
-
-      it('does not modify _id path of the passed in schema the _id is not auto generated (gh-8543)', function() {
-        const model = db.model('Model', new mongoose.Schema({ _id: Number }));
-        const passedInSchema = new mongoose.Schema({});
-        model.discriminator('Discrimintaor', passedInSchema);
-        assert.equal(passedInSchema.path('_id').instance, 'Number');
-      });
-
-      function throwErrorOnClone() { throw new Error('clone() was called on the unrelated schema'); };
-
-      it('when the base schema has an _id that is not auto generated (gh-8543) (gh-8546)', function() {
-        const unrelatedSchema = new mongoose.Schema({});
-        unrelatedSchema.clone = throwErrorOnClone;
-        db.model('UnrelatedModel', unrelatedSchema);
-
-        const model = db.model('Model', new mongoose.Schema({ _id: mongoose.Types.ObjectId }, { _id: false }));
-        model.discriminator('Discrimintaor', new mongoose.Schema({}).clone());
-      });
-    });
   });
 
   describe('bug fixes', function() {
diff --git a/test/model.findOneAndDelete.test.js b/test/model.findOneAndDelete.test.js
index 046fefcac70..04ac46f8210 100644
--- a/test/model.findOneAndDelete.test.js
+++ b/test/model.findOneAndDelete.test.js
@@ -8,7 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -18,12 +17,20 @@ const DocumentObjectId = mongoose.Types.ObjectId;
 describe('model: findOneAndDelete:', function() {
   let Comments;
   let BlogPost;
-  let modelname;
-  let collection;
-  let strictSchema;
   let db;
 
   before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -67,23 +74,11 @@ describe('model: findOneAndDelete:', function() {
       return this;
     });
 
-    modelname = 'DeleteOneBlogPost';
-    mongoose.model(modelname, BlogPost);
-
-    collection = 'deleteoneblogposts';
-
-    strictSchema = new Schema({ name: String }, { strict: true });
-    mongoose.model('DeleteOneStrictSchema', strictSchema);
-
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
+    BlogPost = db.model('BlogPost', BlogPost);
   });
 
   it('returns the original document', function() {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'remove muah';
 
     const post = new M({ title: title });
@@ -101,7 +96,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const now = new Date;
     let query;
@@ -137,7 +132,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     let pending = 5;
 
     M.findOneAndDelete({ name: 'aaron1' }, { select: 'name' }, cb);
@@ -155,7 +150,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('executed with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -169,7 +164,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('executed with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -183,7 +178,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     const _id = new DocumentObjectId;
     let pending = 2;
 
@@ -199,7 +194,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('returns the original document', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'remove muah pleez';
 
     const post = new M({ title: title });
@@ -218,7 +213,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId();
 
     let query;
@@ -240,7 +235,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('supports v3 select string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId();
 
     let query;
@@ -256,7 +251,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('supports v3 select object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     let query;
@@ -272,7 +267,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('supports v3 sort string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId();
 
     let query;
@@ -290,7 +285,7 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('supports v3 sort object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId();
 
     let query;
@@ -308,8 +303,8 @@ describe('model: findOneAndDelete:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', { name: String });
-    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
+    const M = db.model('Test1', { name: String });
+    const N = db.model('Test2', { a: { type: Schema.ObjectId, ref: 'Test1' }, i: Number });
 
     M.create({ name: 'i am an A' }, function(err, a) {
       if (err) return done(err);
@@ -343,7 +338,7 @@ describe('model: findOneAndDelete:', function() {
           }
         }
       });
-      const Model = db.model('gh6203', userSchema);
+      const Model = db.model('Test', userSchema);
 
       yield Model.findOneAndDelete({ foo: '123' }, { name: 'bar' });
 
@@ -368,7 +363,7 @@ describe('model: findOneAndDelete:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('gh-439', s);
+      const Breakfast = db.model('Test', s);
       const breakfast = new Breakfast({
         base: 'eggs'
       });
@@ -405,7 +400,7 @@ describe('model: findOneAndDelete:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('Breakfast', s);
+      const Breakfast = db.model('Test', s);
       const breakfast = new Breakfast({
         base: 'eggs'
       });
diff --git a/test/model.findOneAndRemove.test.js b/test/model.findOneAndRemove.test.js
index e8dd6d4c01f..d6e179f895b 100644
--- a/test/model.findOneAndRemove.test.js
+++ b/test/model.findOneAndRemove.test.js
@@ -8,7 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -18,12 +17,20 @@ const DocumentObjectId = mongoose.Types.ObjectId;
 describe('model: findOneAndRemove:', function() {
   let Comments;
   let BlogPost;
-  let modelname;
-  let collection;
-  let strictSchema;
   let db;
 
   before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -67,23 +74,11 @@ describe('model: findOneAndRemove:', function() {
       return this;
     });
 
-    modelname = 'RemoveOneBlogPost';
-    mongoose.model(modelname, BlogPost);
-
-    collection = 'removeoneblogposts_' + random();
-
-    strictSchema = new Schema({ name: String }, { strict: true });
-    mongoose.model('RemoveOneStrictSchema', strictSchema);
-
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
+    BlogPost = db.model('BlogPost', BlogPost);
   });
 
   it('returns the original document', function() {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'remove muah';
 
     const post = new M({ title: title });
@@ -101,7 +96,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const now = new Date;
     let query;
@@ -137,7 +132,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     let pending = 5;
 
     M.findOneAndRemove({ name: 'aaron1' }, { select: 'name' }, cb);
@@ -155,7 +150,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('executed with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -169,7 +164,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('executed with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -183,7 +178,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     const _id = new DocumentObjectId;
     let pending = 2;
 
@@ -199,7 +194,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('returns the original document', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'remove muah pleez';
 
     const post = new M({ title: title });
@@ -218,7 +213,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     let query;
@@ -240,7 +235,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('supports v3 select string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     let query;
@@ -256,7 +251,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('supports v3 select object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     let query;
@@ -272,7 +267,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('supports v3 sort string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     let query;
@@ -290,7 +285,7 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('supports v3 sort object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     let query;
@@ -308,8 +303,8 @@ describe('model: findOneAndRemove:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', { name: String });
-    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
+    const M = db.model('Test1', { name: String });
+    const N = db.model('Test2', { a: { type: Schema.ObjectId, ref: 'Test1' }, i: Number });
 
     M.create({ name: 'i am an A' }, function(err, a) {
       if (err) return done(err);
@@ -343,7 +338,7 @@ describe('model: findOneAndRemove:', function() {
           }
         }
       });
-      const Model = db.model('gh6203', userSchema);
+      const Model = db.model('Test', userSchema);
 
       yield Model.findOneAndRemove({ foo: '123' }, { name: 'bar' });
 
@@ -368,7 +363,7 @@ describe('model: findOneAndRemove:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('gh-439', s);
+      const Breakfast = db.model('Test', s);
       const breakfast = new Breakfast({
         base: 'eggs'
       });
@@ -405,7 +400,7 @@ describe('model: findOneAndRemove:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('Breakfast', s);
+      const Breakfast = db.model('Test', s);
       const breakfast = new Breakfast({
         base: 'eggs'
       });
diff --git a/test/model.findOneAndReplace.test.js b/test/model.findOneAndReplace.test.js
index d536db9bb76..6b203a6c350 100644
--- a/test/model.findOneAndReplace.test.js
+++ b/test/model.findOneAndReplace.test.js
@@ -8,7 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -18,12 +17,20 @@ const DocumentObjectId = mongoose.Types.ObjectId;
 describe('model: findOneAndReplace:', function() {
   let Comments;
   let BlogPost;
-  let modelname;
-  let collection;
-  let strictSchema;
   let db;
 
   before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema;
 
     Comments.add({
@@ -67,23 +74,11 @@ describe('model: findOneAndReplace:', function() {
       return this;
     });
 
-    modelname = 'ReplaceOneBlogPost';
-    mongoose.model(modelname, BlogPost);
-
-    collection = 'replaceoneblogposts';
-
-    strictSchema = new Schema({ name: String }, { strict: true });
-    mongoose.model('ReplaceOneStrictSchema', strictSchema);
-
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
+    BlogPost = db.model('BlogPost', BlogPost);
   });
 
   it('returns the original document', function() {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'remove muah';
 
     const post = new M({ title: title });
@@ -98,7 +93,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const now = new Date;
     let query;
@@ -134,7 +129,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     let pending = 5;
 
     M.findOneAndReplace({ name: 'aaron1' }, { select: 'name' }, cb);
@@ -152,7 +147,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('executed with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -166,7 +161,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('executed with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -180,7 +175,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     const _id = new DocumentObjectId;
     let pending = 2;
 
@@ -196,7 +191,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('returns the original document', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'remove muah pleez';
 
     const post = new M({ title: title });
@@ -215,7 +210,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId();
 
     let query;
@@ -237,7 +232,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('supports v3 select string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const query = M.findOneAndReplace({}, {}, { select: 'author -title' });
     assert.strictEqual(1, query._fields.author);
@@ -246,7 +241,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('supports v3 select object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const query = M.findOneAndReplace({}, {}, { select: { author: 1, title: 0 } });
     assert.strictEqual(1, query._fields.author);
@@ -255,7 +250,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('supports v3 sort string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const query = M.findOneAndReplace({}, {}, { sort: 'author -title' });
     assert.equal(Object.keys(query.options.sort).length, 2);
@@ -265,7 +260,7 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('supports v3 sort object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const query = M.findOneAndReplace({}, {}, { sort: { author: 1, title: -1 } });
     assert.equal(Object.keys(query.options.sort).length, 2);
@@ -275,8 +270,8 @@ describe('model: findOneAndReplace:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', { name: String });
-    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
+    const M = db.model('Test1', { name: String });
+    const N = db.model('Test2', { a: { type: Schema.ObjectId, ref: 'Test1' }, i: Number });
 
     M.create({ name: 'i am an A' }, function(err, a) {
       if (err) return done(err);
@@ -309,7 +304,7 @@ describe('model: findOneAndReplace:', function() {
           }
         }
       });
-      const Model = db.model('gh6203', userSchema);
+      const Model = db.model('Test', userSchema);
 
       yield Model.findOneAndReplace({ foo: '123' }, { name: 'bar' });
 
@@ -334,7 +329,7 @@ describe('model: findOneAndReplace:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('gh-439', s);
+      const Breakfast = db.model('Test', s);
       const breakfast = new Breakfast({
         base: 'eggs'
       });
@@ -371,7 +366,7 @@ describe('model: findOneAndReplace:', function() {
         ++postCount;
       });
 
-      const Breakfast = db.model('Breakfast', s);
+      const Breakfast = db.model('Test', s);
       const breakfast = new Breakfast({
         base: 'eggs'
       });
@@ -394,7 +389,7 @@ describe('model: findOneAndReplace:', function() {
 
   it('works (gh-7654)', function() {
     const schema = new Schema({ name: String, age: Number });
-    const Model = db.model('gh7654', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.findOneAndReplace({}, { name: 'Jean-Luc Picard', age: 59 }, { upsert: true });
@@ -412,7 +407,7 @@ describe('model: findOneAndReplace:', function() {
 
   it('schema-level projection (gh-7654)', function() {
     const schema = new Schema({ name: String, age: { type: Number, select: false } });
-    const Model = db.model('gh7654_0', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc = yield Model.findOneAndReplace({}, { name: 'Jean-Luc Picard', age: 59 }, {
@@ -426,7 +421,7 @@ describe('model: findOneAndReplace:', function() {
 
   it('supports `new` in addition to `returnOriginal` (gh-7846)', function() {
     const schema = new Schema({ name: String, age: Number });
-    const Model = db.model('gh7846', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       const doc = yield Model.findOneAndReplace({}, { name: 'Jean-Luc Picard', age: 59 }, {
@@ -440,7 +435,7 @@ describe('model: findOneAndReplace:', function() {
 
   it('orFail() (gh-8030)', function() {
     const schema = Schema({ name: String, age: Number });
-    const Model = db.model('gh8030', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let err = yield Model.findOneAndReplace({}, { name: 'test' }).orFail().
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 34c59a3290f..1814a8d56d1 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -23,13 +23,20 @@ const uuid = require('uuid');
 describe('model: findOneAndUpdate:', function() {
   let Comments;
   let BlogPost;
-  let modelname;
-  let collection;
-  let strictSchema;
-  let strictThrowSchema;
   let db;
 
   before(function() {
+    db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
+
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => util.clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema();
 
     Comments.add({
@@ -73,30 +80,11 @@ describe('model: findOneAndUpdate:', function() {
       return this;
     });
 
-    modelname = 'UpdateOneBlogPost';
-    mongoose.model(modelname, BlogPost);
-
-    collection = 'updateoneblogposts_' + random();
-
-    strictSchema = new Schema({ name: String }, { strict: true });
-    mongoose.model('UpdateOneStrictSchema', strictSchema);
-
-    strictThrowSchema = new Schema({ name: String }, { strict: 'throw' });
-    mongoose.model('UpdateOneStrictThrowSchema', strictThrowSchema);
-
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
+    BlogPost = db.model('BlogPost', BlogPost);
   });
 
-  beforeEach(() => db.deleteModel(/.*/));
-
-  afterEach(() => util.clearTestData(db));
-
-  it('WWW returns the edited document', function(done) {
-    const M = db.model(modelname, collection);
+  it('returns the edited document', function(done) {
+    const M = BlogPost;
     const title = 'Tobi ' + random();
     const author = 'Brian ' + random();
     const newTitle = 'Woot ' + random();
@@ -175,7 +163,7 @@ describe('model: findOneAndUpdate:', function() {
   describe('will correctly', function() {
     let ItemParentModel, ItemChildModel;
 
-    before(function() {
+    beforeEach(function() {
       const itemSpec = new Schema({
         item_id: {
           type: ObjectId, required: true, default: function() {
@@ -191,8 +179,8 @@ describe('model: findOneAndUpdate:', function() {
       const itemSchema = new Schema({
         items: [itemSpec]
       });
-      ItemParentModel = db.model('ItemParentModel', itemSchema);
-      ItemChildModel = db.model('ItemChildModel', itemSpec);
+      ItemParentModel = db.model('Test1', itemSchema);
+      ItemChildModel = db.model('Test2', itemSpec);
     });
 
     it('update subdocument in array item', function(done) {
@@ -236,7 +224,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('returns the original document', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'Tobi ' + random();
     const author = 'Brian ' + random();
     const newTitle = 'Woot ' + random();
@@ -296,7 +284,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('allows upserting', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'Tobi ' + random();
     const author = 'Brian ' + random();
     const newTitle = 'Woot ' + random();
@@ -342,8 +330,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
-
+    const M = BlogPost;
     const now = new Date;
     let query;
 
@@ -393,7 +380,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     let pending = 6;
 
     M.findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron6' } }, { new: false }, cb);
@@ -414,7 +401,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('executes when a callback is passed to a succeeding function', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     let pending = 6;
 
     M.findOneAndUpdate({ name: 'aaron' }, { $set: { name: 'Aaron' } }, { new: false }).exec(cb);
@@ -435,7 +422,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('executing with only a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -450,7 +437,6 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('updates numbers atomically', function(done) {
-    const BlogPost = db.model(modelname, collection);
     let totalDocs = 4;
 
     const post = new BlogPost();
@@ -480,7 +466,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('honors strict schemas', function(done) {
-    const S = db.model('UpdateOneStrictSchema');
+    const S = db.model('Test', Schema({ name: String }, { strict: true }));
     const s = new S({ name: 'orange crush' });
 
     s.save(function(err) {
@@ -511,7 +497,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('returns errors with strict:throw schemas', function(done) {
-    const S = db.model('UpdateOneStrictThrowSchema');
+    const S = db.model('Test', Schema({ name: String }, { strict: 'throw' }));
     const s = new S({ name: 'orange crush' });
 
     s.save(function(err) {
@@ -534,7 +520,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('executing with just a callback throws', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     let err;
 
     try {
@@ -549,7 +535,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('executes when a callback is passed', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     const _id = new DocumentObjectId;
     let pending = 2;
 
@@ -567,7 +553,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('executes when a callback is passed to a succeeding function', function(done) {
-    const M = db.model(modelname, collection + random());
+    const M = BlogPost;
     const _id = new DocumentObjectId;
     let pending = 2;
 
@@ -585,7 +571,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('returns the original document', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const title = 'Tobi ' + random();
     const author = 'Brian ' + random();
     const newTitle = 'Woot ' + random();
@@ -645,7 +631,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('options/conditions/doc are merged when no callback is passed', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     const now = new Date;
@@ -675,7 +661,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('supports v3 select string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     const now = new Date;
@@ -692,7 +678,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('supports v3 select object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     const now = new Date;
@@ -709,7 +695,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('supports v3 sort string syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
 
     const now = new Date;
     const _id = new DocumentObjectId;
@@ -748,7 +734,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('supports v3 sort object syntax', function(done) {
-    const M = db.model(modelname, collection);
+    const M = BlogPost;
     const _id = new DocumentObjectId;
 
     const now = new Date;
@@ -773,6 +759,7 @@ describe('model: findOneAndUpdate:', function() {
       title: String
     });
 
+    db.deleteModel(/BlogPost/);
     const B = db.model('BlogPost', postSchema);
     const _id1 = new mongoose.Types.ObjectId;
     const _id2 = new mongoose.Types.ObjectId;
@@ -796,8 +783,8 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('supports population (gh-1395)', function(done) {
-    const M = db.model('A', { name: String });
-    const N = db.model('B', { a: { type: Schema.ObjectId, ref: 'A' }, i: Number });
+    const M = db.model('Test1', { name: String });
+    const N = db.model('Test2', { a: { type: Schema.ObjectId, ref: 'Test1' }, i: Number });
 
     M.create({ name: 'i am an A' }, function(err, a) {
       if (err) {
@@ -831,7 +818,7 @@ describe('model: findOneAndUpdate:', function() {
       }
     });
 
-    const Thing = db.model('Thing', thingSchema);
+    const Thing = db.model('Test', thingSchema);
     const key = 'some-id';
 
     Thing.findOneAndUpdate({ _id: key }, { $set: { flag: false } }, { upsert: true, new: false }).exec(function(err, thing) {
@@ -889,17 +876,17 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('allows properties to be set to null gh-1643', function(done) {
-    const thingSchema = new Schema({
+    const testSchema = new Schema({
       name: [String]
     });
 
-    const Thing = db.model('Thing1', thingSchema);
+    const Test = db.model('Test', testSchema);
 
-    Thing.create({ name: ['Test'] }, function(err, thing) {
+    Test.create({ name: ['Test'] }, function(err, thing) {
       if (err) {
         return done(err);
       }
-      Thing.findOneAndUpdate({ _id: thing._id }, { name: null }, { new: true })
+      Test.findOneAndUpdate({ _id: thing._id }, { name: null }, { new: true })
         .exec(function(err, doc) {
           if (err) {
             return done(err);
@@ -912,7 +899,7 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('honors the overwrite option (gh-1809)', function(done) {
-    const M = db.model('1809', { name: String, change: Boolean });
+    const M = db.model('Test', { name: String, change: Boolean });
     M.create({ name: 'first' }, function(err, doc) {
       if (err) {
         return done(err);
@@ -929,24 +916,24 @@ describe('model: findOneAndUpdate:', function() {
   });
 
   it('can do deep equals on object id after findOneAndUpdate (gh-2070)', function(done) {
-    const accountSchema = new Schema({
+    const userSchema = new Schema({
       name: String,
       contacts: [{
-        account: { type: Schema.Types.ObjectId, ref: 'Account' },
+        account: { type: Schema.Types.ObjectId, ref: 'User' },
         name: String
       }]
     });
 
-    const Account = db.model('2070', accountSchema);
+    const User = db.model('User', userSchema);
 
-    const a1 = new Account({ name: 'parent' });
-    const a2 = new Account({ name: 'child' });
+    const a1 = new User({ name: 'parent' });
+    const a2 = new User({ name: 'child' });
 
     a1.save(function(error) {
       assert.ifError(error);
       a2.save(function(error, a2) {
         assert.ifError(error);
-        Account.findOneAndUpdate(
+        User.findOneAndUpdate(
           { name: 'parent' },
           { $push: { contacts: { account: a2._id, name: 'child' } } },
           { new: true },
@@ -961,7 +948,7 @@ describe('model: findOneAndUpdate:', function() {
               assert.ok(isEqual(doc.contacts[0].account, a2._id));
             }
 
-            Account.findOne({ name: 'parent' }, function(error, doc) {
+            User.findOne({ name: 'parent' }, function(error, doc) {
               assert.ifError(error);
               assert.ok(Utils.deepEqual(doc.contacts[0].account, a2._id));
               assert.ok(isEqualWith(doc.contacts[0].account, a2._id, compareBuffers));
@@ -986,7 +973,7 @@ describe('model: findOneAndUpdate:', function() {
       name: String
     });
 
-    const Account = db.model('2122', accountSchema);
+    const Account = db.model('Test', accountSchema);
 
     Account.findOneAndUpdate(
       { name: 'account' },
@@ -1169,7 +1156,7 @@ describe('model: findOneAndUpdate:', function() {
         topping: { type: String, default: 'bacon' },
         base: String
       });
-      const Breakfast = db.model('fam-gh-860-0', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { upsert: true, setDefaultsOnInsert: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1194,7 +1181,7 @@ describe('model: findOneAndUpdate:', function() {
         numEggs: { type: Number, default: 3 },
         base: String
       }, { versionKey: null });
-      const Breakfast = db.model('fam-gh-860-1', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { upsert: true, setDefaultsOnInsert: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1215,7 +1202,7 @@ describe('model: findOneAndUpdate:', function() {
         topping: { type: String, default: 'bacon' },
         base: String
       });
-      const Breakfast = db.model('fam-gh-860-2', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { upsert: true, setDefaultsOnInsert: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1269,7 +1256,7 @@ describe('model: findOneAndUpdate:', function() {
           }
         }
       });
-      const Breakfast = db.model('fam-gh-860-3', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = {
         upsert: true,
@@ -1302,7 +1289,7 @@ describe('model: findOneAndUpdate:', function() {
           }
         }
       });
-      const Breakfast = db.model('fam-gh-860-4', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { runValidators: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1327,7 +1314,7 @@ describe('model: findOneAndUpdate:', function() {
         eggs: { type: Number, min: 4, max: 6 },
         bacon: { type: String, match: /strips/ }
       });
-      const Breakfast = db.model('fam-gh-860-5', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { runValidators: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1372,7 +1359,7 @@ describe('model: findOneAndUpdate:', function() {
         eggs: { type: Number, min: 4, max: 6 },
         bacon: { type: String, match: /strips/ }
       });
-      const Breakfast = db.model('fam-gh-860-6', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { runValidators: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1394,7 +1381,7 @@ describe('model: findOneAndUpdate:', function() {
         steak: { type: String, required: true },
         eggs: { type: Number, min: 4 }
       });
-      const Breakfast = db.model('fam-gh-860-7', s);
+      const Breakfast = db.model('Test', s);
 
       const updateOptions = { runValidators: true, upsert: true, new: true };
       Breakfast.findOneAndUpdate(
@@ -1790,7 +1777,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       }, options);
 
-      const Collection = db.model('test', CollectionSchema);
+      const Collection = db.model('Test', CollectionSchema);
 
       Collection.create({ field2: { arrayField: [] } }).
         then(function(doc) {
@@ -2300,7 +2287,7 @@ describe('model: findOneAndUpdate:', function() {
         }
       });
 
-      const Book = db.model('Book', bookSchema);
+      const Book = db.model('Test', bookSchema);
 
       return Book.findOneAndUpdate({}, { genres: ['Sci-Fi'] }, { upsert: true }).
         then(() => Book.findOne()).
diff --git a/test/model.hydrate.test.js b/test/model.hydrate.test.js
index 28b55804367..fb8896b27e8 100644
--- a/test/model.hydrate.test.js
+++ b/test/model.hydrate.test.js
@@ -43,9 +43,9 @@ describe('model', function() {
       });
 
       db = start();
-      B = db.model('model-create', schemaB, 'gh-2637-1');
+      B = db.model('Test', schemaB);
       B.discriminator('C', schemaC);
-      Breakfast = db.model('gh-2637-2', breakfastSchema, 'gh-2637-2');
+      Breakfast = db.model('Test1', breakfastSchema);
 
       return db;
     });
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index b3c341781d9..6d08cb8f71f 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -19,14 +19,21 @@ describe('model', function() {
 
   before(function() {
     db = start();
+
+    return db.createCollection('Test');
   });
 
   after(function(done) {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   describe('indexes', function() {
-    it('are created when model is compiled', function(done) {
+    this.timeout(5000);
+
+    it('are created when model is compiled', function() {
       const Indexed = new Schema({
         name: { type: String, index: true },
         last: String,
@@ -37,30 +44,28 @@ describe('model', function() {
       Indexed.index({ last: 1, email: 1 }, { unique: true });
       Indexed.index({ date: 1 }, { expires: 10 });
 
-      const IndexedModel = db.model('IndexedModel1', Indexed, 'indexedmodel' + random());
+      const IndexedModel = db.model('Test', Indexed);
       let assertions = 0;
 
-      IndexedModel.on('index', function() {
-        IndexedModel.collection.getIndexes({ full: true }, function(err, indexes) {
-          assert.ifError(err);
-
-          indexes.forEach(function(index) {
-            switch (index.name) {
-              case '_id_':
-              case 'name_1':
-              case 'last_1_email_1':
-                assertions++;
-                break;
-              case 'date_1':
-                assertions++;
-                assert.equal(index.expireAfterSeconds, 10);
-                break;
-            }
-          });
-
-          assert.equal(assertions, 4);
-          done();
+      return co(function*() {
+        yield cb => IndexedModel.on('index', () => cb());
+        const indexes = yield IndexedModel.collection.getIndexes({ full: true });
+
+        indexes.forEach(function(index) {
+          switch (index.name) {
+            case '_id_':
+            case 'name_1':
+            case 'last_1_email_1':
+              assertions++;
+              break;
+            case 'date_1':
+              assertions++;
+              assert.equal(index.expireAfterSeconds, 10);
+              break;
+          }
         });
+
+        assert.equal(assertions, 4);
       });
     });
 
@@ -76,7 +81,7 @@ describe('model', function() {
         blogposts: [BlogPosts]
       });
 
-      const UserModel = db.model('DeepIndexedModel2', User, 'deepindexedmodel' + random());
+      const UserModel = db.model('Test', User);
       let assertions = 0;
 
       UserModel.on('index', function() {
@@ -129,7 +134,7 @@ describe('model', function() {
         otherArr: [otherSchema]
       });
 
-      const UserModel = db.model('gh5575', User);
+      const UserModel = db.model('Test', User);
 
       UserModel.on('index', function() {
         UserModel.collection.getIndexes(function(err, indexes) {
@@ -156,7 +161,7 @@ describe('model', function() {
         featured: [BlogPosts]
       });
 
-      const UserModel = db.model('DeepIndexedModelMulti3', User, 'gh2322');
+      const UserModel = db.model('Test', User);
       let assertions = 0;
 
       UserModel.on('index', function() {
@@ -204,7 +209,7 @@ describe('model', function() {
         blogposts: [BlogPosts]
       });
 
-      const UserModel = db.model('DeepCompoundIndexModel4', User, 'deepcompoundindexmodel' + random());
+      const UserModel = db.model('Test', User);
       let found = 0;
 
       UserModel.on('index', function() {
@@ -271,7 +276,7 @@ describe('model', function() {
 
     it('error should emit on the model', function(done) {
       const schema = new Schema({ name: { type: String } });
-      const Test = db.model('IndexError5', schema, 'x' + random());
+      const Test = db.model('Test', schema);
 
       Test.create({ name: 'hi' }, { name: 'hi' }, function(err) {
         assert.strictEqual(err, null);
@@ -301,12 +306,10 @@ describe('model', function() {
       User2.index({ name: 1 }, { unique: true });
       User2.index({ secondValue: 1 });
 
-      const collectionName = 'deepindexedmodel' + random();
-      // Create model with first schema to initialize indexes
-      db.model('SingleIndexedModel', User, collectionName);
+      db.model('Test1', User, 'Test');
 
       // Create model with second schema in same collection to add new indexes
-      const UserModel2 = db.model('DuplicateIndexedModel', User2, collectionName);
+      const UserModel2 = db.model('Test2', User2, 'Test');
       let assertions = 0;
 
       UserModel2.on('index', function() {
@@ -337,7 +340,7 @@ describe('model', function() {
         const schema = new Schema({ name: { type: String, index: true } });
         schema.set('autoIndex', false);
 
-        const Test = db.model('AutoIndexing6', schema, 'autoindexing-disable');
+        const Test = db.model('Test', schema);
         Test.on('index', function() {
           assert.ok(false, 'Model.ensureIndexes() was called');
         });
@@ -360,7 +363,7 @@ describe('model', function() {
       describe('global autoIndexes (gh-1875)', function() {
         it('will create indexes as a default', function(done) {
           const schema = new Schema({ name: { type: String, index: true } });
-          const Test = db.model('GlobalAutoIndex7', schema, 'gh-1875-1');
+          const Test = db.model('Test', schema);
           Test.on('index', function(error) {
             assert.ifError(error);
             assert.ok(true, 'Model.ensureIndexes() was called');
@@ -375,7 +378,7 @@ describe('model', function() {
         it('will not create indexes if the global auto index is false and schema option isnt set (gh-1875)', function(done) {
           const db = start({ config: { autoIndex: false } });
           const schema = new Schema({ name: { type: String, index: true } });
-          const Test = db.model('GlobalAutoIndex8', schema, 'x' + random());
+          const Test = db.model('Test', schema);
           Test.on('index', function() {
             assert.ok(false, 'Model.ensureIndexes() was called');
           });
@@ -431,18 +434,20 @@ describe('model', function() {
   });
 
   describe('discriminators with unique', function() {
+    this.timeout(5000);
+
     it('converts to partial unique index (gh-6347)', function() {
       const baseOptions = { discriminatorKey: 'kind' };
       const baseSchema = new Schema({}, baseOptions);
 
-      const Base = db.model('gh6347_Base', baseSchema);
+      const Base = db.model('Test', baseSchema);
 
       const userSchema = new Schema({
         emailId: { type: String, unique: true }, // Should become a partial
         firstName: { type: String }
       });
 
-      const User = Base.discriminator('gh6347_User', userSchema);
+      const User = Base.discriminator('User', userSchema);
 
       const deviceSchema = new Schema({
         _id: { type: Schema.ObjectId, auto: true },
@@ -450,7 +455,7 @@ describe('model', function() {
         model: { type: String }
       });
 
-      const Device = Base.discriminator('gh6347_Device', deviceSchema);
+      const Device = Base.discriminator('Device', deviceSchema);
 
       return Promise.all([
         Base.init(),
@@ -466,14 +471,14 @@ describe('model', function() {
       const baseOptions = { discriminatorKey: 'kind' };
       const baseSchema = new Schema({}, baseOptions);
 
-      const Base = db.model('gh6347_Base_0', baseSchema);
+      const Base = db.model('Test', baseSchema);
 
       const userSchema = new Schema({
         emailId: { type: String, unique: true }, // Should become a partial
         firstName: { type: String }
       });
 
-      const User = Base.discriminator('gh6347_User_0', userSchema);
+      const User = Base.discriminator('User', userSchema);
 
       return User.init().
         then(() => User.syncIndexes()).
@@ -482,11 +487,11 @@ describe('model', function() {
 
     it('different collation with syncIndexes() (gh-8521)', function() {
       return co(function*() {
-        yield db.db.collection('users').drop().catch(() => {});
+        yield db.db.collection('User').drop().catch(() => {});
 
         let userSchema = new mongoose.Schema({ username: String });
         userSchema.index({ username: 1 }, { unique: true });
-        let User = db.model('User', userSchema);
+        let User = db.model('User', userSchema, 'User');
 
         yield User.init();
         let indexes = yield User.listIndexes();
@@ -503,7 +508,7 @@ describe('model', function() {
           }
         });
         db.deleteModel('User');
-        User = db.model('User', userSchema);
+        User = db.model('User', userSchema, 'User');
 
         yield User.init();
         yield User.syncIndexes();
@@ -519,9 +524,9 @@ describe('model', function() {
 
     it('cleanIndexes (gh-6676)', function() {
       return co(function*() {
-        let M = db.model('gh6676', new Schema({
+        let M = db.model('Test', new Schema({
           name: { type: String, index: true }
-        }, { autoIndex: false }), 'gh6676');
+        }, { autoIndex: false }), 'Test');
 
         yield M.createIndexes();
 
@@ -531,9 +536,9 @@ describe('model', function() {
           { name: 1 }
         ]);
 
-        M = db.model('gh6676_2', new Schema({
+        M = db.model('Test', new Schema({
           name: String
-        }, { autoIndex: false }), 'gh6676');
+        }, { autoIndex: false }), 'Test');
 
         yield M.cleanIndexes();
         indexes = yield M.listIndexes();
diff --git a/test/model.middleware.test.js b/test/model.middleware.test.js
index a3604c7bd18..f439c5494ef 100644
--- a/test/model.middleware.test.js
+++ b/test/model.middleware.test.js
@@ -23,6 +23,9 @@ describe('model middleware', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('post save', function(done) {
     const schema = new Schema({
       title: String
@@ -51,7 +54,7 @@ describe('model middleware', function() {
       next();
     });
 
-    const TestMiddleware = db.model('TestPostSaveMiddleware', schema);
+    const TestMiddleware = db.model('Test', schema);
 
     const test = new TestMiddleware({ title: 'Little Green Running Hood' });
 
@@ -72,7 +75,7 @@ describe('model middleware', function() {
       throw new Error('woops!');
     });
 
-    const TestMiddleware = db.model('gh3483_post', schema);
+    const TestMiddleware = db.model('Test', schema);
 
     const test = new TestMiddleware({ title: 'Test' });
 
@@ -98,7 +101,7 @@ describe('model middleware', function() {
       });
     });
 
-    const TestMiddleware = db.model('gh3779_pre', schema);
+    const TestMiddleware = db.model('Test', schema);
 
     const test = new TestMiddleware({ title: 'Test' });
 
@@ -123,7 +126,7 @@ describe('model middleware', function() {
       });
     });
 
-    const TestMiddleware = db.model('gh3779_post', schema);
+    const TestMiddleware = db.model('Test', schema);
 
     const test = new TestMiddleware({ title: 'Test' });
 
@@ -150,7 +153,7 @@ describe('model middleware', function() {
       next();
     });
 
-    const Book = db.model('gh2462', schema);
+    const Book = db.model('Test', schema);
 
     Book.create({}, function() {
       assert.equal(count, 2);
@@ -217,7 +220,7 @@ describe('model middleware', function() {
         doc.loadedAt = now;
       });
 
-      const Test = db.model('TestPostInitMiddleware', schema);
+      const Test = db.model('Test', schema);
 
       return Test.create({ title: 'Casino Royale' }).
         then(doc => Test.findById(doc)).
@@ -235,7 +238,7 @@ describe('model middleware', function() {
       schema.pre('init', () => Promise.reject(swallowedError));
       schema.post('init', () => { throw Error('will show'); });
 
-      const Test = db.model('PostInitBook', schema);
+      const Test = db.model('Test', schema);
 
       return Test.create({ title: 'Casino Royale' }).
         then(doc => Test.findById(doc)).
@@ -269,7 +272,7 @@ describe('model middleware', function() {
       next();
     });
 
-    const Parent = db.model('gh-1829', parentSchema, 'gh-1829');
+    const Parent = db.model('Parent', parentSchema);
 
     const parent = new Parent({
       name: 'Han',
@@ -308,7 +311,7 @@ describe('model middleware', function() {
       throw new Error('woops!');
     });
 
-    const TestMiddleware = db.model('gh3483_pre', schema);
+    const TestMiddleware = db.model('Test', schema);
 
     const test = new TestMiddleware({ title: 'Test' });
 
@@ -337,7 +340,7 @@ describe('model middleware', function() {
       next();
     });
 
-    const TestMiddleware = db.model('gh3483_pre_2', schema);
+    const TestMiddleware = db.model('Test', schema);
 
     const test = new TestMiddleware({ title: 'Test' });
 
@@ -378,7 +381,7 @@ describe('model middleware', function() {
       ++postRemove;
     });
 
-    const Test = db.model('TestPostValidateMiddleware', schema);
+    const Test = db.model('Test', schema);
 
     const test = new Test({ title: 'banana' });
 
@@ -420,7 +423,7 @@ describe('model middleware', function() {
       assert.equal(docs[0].name, 'foo');
     });
 
-    const Model = db.model('gh5982', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.create({ name: 'foo' });
@@ -453,7 +456,7 @@ describe('model middleware', function() {
       ++postCalled;
     });
 
-    const Model = db.model('gh7538', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       yield Model.create({ name: 'foo' });

From 163eb0726c67862795fade80e0db71bdd0a3c868 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Mar 2020 19:27:52 -0400
Subject: [PATCH 0619/2348] test: fix tests

---
 test/model.discriminator.test.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 1ebb9ee415b..7c0643f61df 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1345,6 +1345,7 @@ describe('model', function() {
         }
       }
 
+      mongoose.deleteModel(/Test/);
       const UserModel = mongoose.model(Test, new mongoose.Schema({}));
 
       const u = new UserModel({});

From 7053743be587ee02de3ac568eb07e7f8a0a8ed20 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 21 Mar 2020 09:43:09 +0200
Subject: [PATCH 0620/2348] Use golang style for catching error in test
 refactor

---
 test/model.test.js | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index e0ea3df06fe..0052d31f4ef 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5541,18 +5541,14 @@ describe('Model', function() {
         return co(function*() {
           const createdUser = yield User.create({ name: 'Hafez' });
 
-          let err;
+          const err = yield User.bulkWrite([{
+            updateOne: {
+              filter: { _id: createdUser._id }
+            }
+          }])
+            .then(()=>null)
+            .catch(err=>err);
 
-          try {
-            yield User.bulkWrite([{
-              updateOne: {
-                filter: { _id: createdUser._id }
-              }
-            }]);
-          }
-          catch (_err) {
-            err = _err;
-          }
 
           assert.ok(err);
           assert.equal(err.message, 'Must provide an update object.');

From c4c6bf87da375d9bee4e2d19d6d06457125ce33b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Mar 2020 14:22:51 -0400
Subject: [PATCH 0621/2348] docs(connections): expand section about multiple
 connections to describe patterns for exporting schemas

Fix #8679
---
 docs/connections.pug | 59 +++++++++++++++++++++++++++++++++-----------
 1 file changed, 44 insertions(+), 15 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index dd776fa4df9..3767aca5db0 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -386,11 +386,14 @@ block content
     <h3 id="multiple_connections"><a href="#multiple_connections">Multiple connections</a></h3>
 
     So far we've seen how to connect to MongoDB using Mongoose's default
-    connection. At times we may need multiple connections open to Mongo, each
-    with different read/write settings, or maybe just to different databases for
-    example. In these cases we can utilize `mongoose.createConnection()` which
-    accepts all the arguments already discussed and returns a fresh connection
-    for you.
+    connection. Mongoose creates a _default connection_ when you call `mongoose.connect()`.
+    You can access the default connection using `mongoose.connection`.
+    
+    You may need multiple connections to MongoDB for several reasons.
+    One reason is if you have multiple databases or multiple MongoDB clusters.
+    Another reason is to work around [slow trains](https://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
+    The `mongoose.createConnection()` function takes the same arguments as
+    `mongoose.connect()` and returns a new connection.
 
     ```javascript
     const conn = mongoose.createConnection('mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]', options);
@@ -405,12 +408,13 @@ block content
     ```
 
     If you use multiple connections, you should make sure you export schemas,
-    **not** models.
+    **not** models. Exporting a model from a file is called the _export model pattern_.
+    The export model pattern is limited because you can only use one connection.
 
     ```javascript
     const userSchema = new Schema({ name: String, email: String });
 
-    // The correct pattern is to export a schema
+    // The alternative to the export model pattern is the export schema pattern.
     module.exports = userSchema;
 
     // Because if you export a model as shown below, the model will be scoped
@@ -418,19 +422,44 @@ block content
     // module.exports = mongoose.model('User', userSchema);
     ```
 
-    In addition, you should define a factory function that registers models on a
-    connection to make it easy to register all your models on a given connection.
+    If you use the export schema pattern, you still need to create models
+    somewhere. There are two common patterns. First is to export a connection
+    and register the models on the connection in the file:
 
     ```javascript
-    const userSchema = require('./userSchema');
+    // connections/fast.js
+    const mongoose = require('mongoose');
 
-    module.exports = conn => {
-      conn.model('User', userSchema);
-    };
+    const conn = mongoose.createConnection(process.env.MONGODB_URI);
+    conn.model('User', require('../schemas/user'));
+
+    module.exports = conn;
+
+    // connections/slow.js
+    const mongoose = require('mongoose');
+
+    const conn = mongoose.createConnection(process.env.MONGODB_URI);
+    conn.model('User', require('../schemas/user'));
+    conn.model('PageView', require('../schemas/pageView'));
+
+    module.exports = conn;
     ```
 
-    Mongoose creates a _default connection_ when you call `mongoose.connect()`.
-    You can access the default connection using `mongoose.connection`.
+    Another alternative is to register connections with a dependency injector
+    or another [inversion of control (IOC) pattern](https://thecodebarbarian.com/using-ramda-as-a-dependency-injector).
+
+    ```javascript
+    const mongoose = require('mongoose');
+
+    module.exports = function connectionFactory() {
+      const conn = mongoose.createConnection(process.env.MONGODB_URI);
+
+      conn.model('User', require('../schemas/user'));
+      conn.model('PageView', require('../schemas/pageView'));
+
+      return conn; 
+    };
+    ```
 
     <h3 id="connection_pools"><a href="#connection_pools">Connection Pools</a></h3>
 

From cfd529401da0c75ed1759468db847efec3abd2cc Mon Sep 17 00:00:00 2001
From: Mateusz <32672634+MateRyze@users.noreply.github.com>
Date: Sat, 21 Mar 2020 20:24:00 +0100
Subject: [PATCH 0622/2348] fix typos

---
 docs/guide.pug | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index eed951366d7..a9edadd4fa1 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -157,7 +157,7 @@ block content
 
     Instances of `Models` are [documents](./documents.html). Documents have
     many of their own [built-in instance methods](./api.html#document-js).
-    We may also define our own custom document instance methods too.
+    We may also define our own custom document instance methods.
 
     ```javascript
       // define a schema
@@ -205,7 +205,7 @@ block content
 
       const Animal = mongoose.model('Animal', animalSchema);
       let animals = await Animal.findByName('fido');
-      animls = animals.concat(await Animal.findByBreed('Poodle'));
+      animals = animals.concat(await Animal.findByBreed('Poodle'));
     ```
 
     Do **not** declare statics using ES6 arrow functions (`=>`). Arrow functions [explicitly prevent binding `this`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this), so the above examples will not work because of the value of `this`.
@@ -1129,7 +1129,7 @@ block content
     ```
 
     Set the `storeSubdocValidationError` to `false` on the child schema to make
-    Mongoose only report the parent error.
+    Mongoose only reports the parent error.
 
     ```javascript
     const childSchema = new Schema({
@@ -1189,7 +1189,7 @@ block content
     [_The Little MongoDB Schema Design Book_](http://bit.ly/mongodb-schema-design)
     by Christian Kvalheim, the original author of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb).
     This book shows you how to implement performant schemas for a laundry list
-    of use cases, including ecommerce, wikis, and appointment bookings.
+    of use cases, including e-commerce, wikis, and appointment bookings.
 
     <h3 id="next">Next Up</h3>
 

From b84a33812ec764961319d2ab979cadf22730a5b7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Mar 2020 21:14:47 -0400
Subject: [PATCH 0623/2348] test: remove remaining unnecessary collections

Fix #8481
---
 test/collection.capped.test.js            | 75 +++++------------------
 test/colors.js                            |  2 +-
 test/connection.test.js                   | 32 ++++++----
 test/document.test.js                     | 22 +++----
 test/es-next/asyncIterator.test.es6.js    |  4 +-
 test/index.test.js                        |  2 +-
 test/model.discriminator.querying.test.js |  4 +-
 test/model.discriminator.test.js          |  9 +--
 test/object.create.null.test.js           |  2 +-
 test/plugin.idGetter.test.js              |  9 ++-
 test/query.cursor.test.js                 |  1 -
 test/query.toconstructor.test.js          | 59 ++++++------------
 test/schema.alias.test.js                 | 10 ++-
 test/schema.boolean.test.js               | 68 ++------------------
 test/schema.date.test.js                  |  3 +-
 test/schema.onthefly.test.js              | 20 +++---
 test/schema.select.test.js                | 47 +++++++-------
 test/schema.timestamps.test.js            | 17 +++--
 test/timestamps.test.js                   | 29 +++++----
 test/types.buffer.test.js                 | 32 ++++++----
 test/types.decimal128.test.js             |  3 +-
 test/types.documentarray.test.js          | 56 ++++++++---------
 test/types.subdocument.test.js            |  4 +-
 test/utils.test.js                        |  6 +-
 test/versioning.test.js                   | 46 ++++++++------
 25 files changed, 239 insertions(+), 323 deletions(-)

diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index 86d9d8b0c71..330593063cc 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -8,17 +8,10 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
-/**
- * setup
- */
-const capped = new Schema({ key: 'string', val: 'number' });
-capped.set('capped', { size: 1000 });
-const coll = 'capped_' + random();
 
 /**
  * Test.
@@ -36,61 +29,27 @@ describe('collections: capped:', function() {
   });
 
   it('schemas should have option size', function(done) {
+    const capped = new Schema({ key: String });
+    capped.set('capped', { size: 1000 });
+
     assert.ok(capped.options.capped);
     assert.equal(capped.options.capped.size, 1000);
     done();
   });
-  it('creation', function(done) {
-    const Capped = db.model('Capped', capped, coll);
-    Capped.collection.isCapped(function(err, isCapped) {
-      assert.ifError(err);
-      assert.ok(isCapped, 'should create a capped collection');
-
-      // use the existing capped collection in the db (no coll creation)
-      const Capped2 = db.model('Capped2', capped, coll);
-      Capped2.collection.isCapped(function(err1, isCapped1) {
-        assert.ifError(err1);
-        assert.ok(isCapped1, 'should reuse the capped collection in the db');
-        assert.equal(Capped.collection.name, Capped2.collection.name);
-        done();
-      });
-    });
-  });
-  it('creation using a number', function(done) {
-    const schema = new Schema({ key: 'string' }, { capped: 8192 });
-    const Capped = db.model('Capped3', schema);
-    Capped.collection.options(function(err, options) {
-      assert.ifError(err);
-      assert.ok(options.capped, 'should create a capped collection');
-      assert.equal(options.size, 8192);
-      done();
-    });
-  });
-  it('attempting to use existing non-capped collection as capped emits error', function(done) {
-    db = start();
-    const opts = {};
-    const conn = 'capped_existing_' + random();
-
-    db.on('open', function() {
-      db.db.createCollection(conn, opts, function(err) {
-        if (err) {
-          db.close();
-        }
-        assert.ifError(err);
-
-        db.on('error', function(err1) {
-          clearTimeout(timer);
-          db.close();
-          assert.ok(/non-capped collection exists/.test(err1));
-          done();
-        });
-
-        db.model('CappedExisting', capped, conn);
-        const timer = setTimeout(function() {
-          db.close();
-          throw new Error('capped test timeout');
-        }, 900);
-      });
+  it('creation', function() {
+    this.timeout(30000);
+
+    return co(function*() {
+      yield db.dropCollection('Test').catch(() => {});
+
+      const capped = new Schema({ key: String });
+      capped.set('capped', { size: 1000 });
+      const Capped = db.model('Test', capped, 'Test');
+      yield Capped.init();
+      yield cb => setTimeout(cb, 100);
+
+      const isCapped = yield Capped.collection.isCapped();
+      assert.ok(isCapped);
     });
   });
 
diff --git a/test/colors.js b/test/colors.js
index 224beb24aa7..db25a062f1a 100644
--- a/test/colors.js
+++ b/test/colors.js
@@ -57,7 +57,7 @@ describe('debug: colors', function() {
 
   before(function() {
     db = start();
-    Test = db.model('Test', test, 'TEST');
+    Test = db.model('Test', test, 'Test');
   });
 
   after(function(done) {
diff --git a/test/connection.test.js b/test/connection.test.js
index 759aa8a0839..1fd381360c4 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -553,8 +553,12 @@ describe('connections:', function() {
       db.close(done);
     });
 
+    beforeEach(function() {
+      db.deleteModel(/.*/);
+    });
+
     it('allows passing a schema', function(done) {
-      const MyModel = db.model('MyModelasdf', new Schema({
+      const MyModel = mongoose.model('Test', new Schema({
         name: String
       }));
 
@@ -575,20 +579,21 @@ describe('connections:', function() {
     });
 
     it('prevents overwriting pre-existing models', function(done) {
-      const name = 'gh-1209-a';
-      db.model(name, new Schema);
+      db.deleteModel(/Test/);
+      db.model('Test', new Schema);
 
       assert.throws(function() {
-        db.model(name, new Schema);
-      }, /Cannot overwrite `gh-1209-a` model/);
+        db.model('Test', new Schema);
+      }, /Cannot overwrite `Test` model/);
 
       done();
     });
 
     it('allows passing identical name + schema args', function(done) {
-      const name = 'gh-1209-b';
+      const name = 'Test';
       const schema = new Schema;
 
+      db.deleteModel(/Test/);
       const model = db.model(name, schema);
       db.model(name, model.schema);
 
@@ -609,8 +614,9 @@ describe('connections:', function() {
 
       const db = start();
 
-      const A = mongoose.model('gh-1209-a', s1);
-      const B = db.model('gh-1209-a', s2);
+      mongoose.deleteModel(/Test/);
+      const A = mongoose.model('Test', s1);
+      const B = db.model('Test', s2);
 
       assert.ok(A.schema !== B.schema);
       assert.ok(A.schema.paths.one);
@@ -619,8 +625,8 @@ describe('connections:', function() {
       assert.ok(!A.schema.paths.two);
 
       // reset
-      delete db.models['gh-1209-a'];
-      const C = db.model('gh-1209-a');
+      delete db.models['Test'];
+      const C = db.model('Test');
       assert.ok(C.schema === A.schema);
 
       db.close();
@@ -641,7 +647,7 @@ describe('connections:', function() {
       describe('when model name already exists', function() {
         it('returns a new uncached model', function(done) {
           const s1 = new Schema({ a: [] });
-          const name = 'non-cached-collection-name';
+          const name = 'Test';
           const A = db.model(name, s1);
           const B = db.model(name);
           const C = db.model(name, 'alternate');
@@ -830,8 +836,8 @@ describe('connections:', function() {
         thing: Number
       });
 
-      const m1 = db.model('testMod', schema);
-      const m2 = db2.model('testMod', schema);
+      const m1 = db.model('Test', schema);
+      const m2 = db2.model('Test', schema);
 
       m1.create({ body: 'this is some text', thing: 1 }, function(err, i1) {
         assert.ifError(err);
diff --git a/test/document.test.js b/test/document.test.js
index 34b4de73097..2edbcf1a8e5 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -12,7 +12,6 @@ const EmbeddedDocument = require('../lib/types/embedded');
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 const util = require('./util');
 const utils = require('../lib/utils');
 const validator = require('validator');
@@ -572,7 +571,7 @@ describe('document', function() {
       }
     }, { _id: false, id: false });
     const keySchema = Schema({ ql: [questionSchema] }, { _id: false, id: false });
-    const Model = db.model('gh8468-2', Schema({
+    const Model = db.model('Test', Schema({
       name: String,
       keys: [keySchema]
     }));
@@ -1239,8 +1238,6 @@ describe('document', function() {
   });
 
   describe('#validate', function() {
-    const collection = 'validateschema_' + random();
-
     it('works (gh-891)', function(done) {
       let schema = null;
       let called = false;
@@ -1255,7 +1252,7 @@ describe('document', function() {
         nick: { type: String, required: true }
       });
 
-      const M = db.model('Test', schema, collection);
+      const M = db.model('Test', schema);
       const m = new M({ prop: 'gh891', nick: 'validation test' });
       m.save(function(err) {
         assert.ifError(err);
@@ -1430,7 +1427,7 @@ describe('document', function() {
           arr: { type: [], required: true, validate: validate }
         });
 
-        const M = db.model('Test', schema, collection);
+        const M = db.model('Test', schema);
         const m = new M({ name: 'gh1109-3', arr: null });
         m.save(function(err) {
           assert.equal(err.errors.arr.message, 'Path `arr` is required.');
@@ -4368,7 +4365,7 @@ describe('document', function() {
       };
 
       const schemaWithTimestamps = new Schema(schemaDefinition, { timestamps: { createdAt: 'misc.createdAt' } });
-      const PersonWithTimestamps = db.model('Person_timestamps', schemaWithTimestamps);
+      const PersonWithTimestamps = db.model('Person', schemaWithTimestamps);
       const dude = new PersonWithTimestamps({ name: 'Keanu', misc: { hometown: 'Beirut' } });
       assert.equal(dude.misc.isAlive, true);
 
@@ -4801,7 +4798,7 @@ describe('document', function() {
         hook: { type: String }
       });
 
-      const Model = db.model('Model', schema);
+      const Model = db.model('Test', schema);
 
       Model.create({ hook: 'test ' }, function(error) {
         assert.ifError(error);
@@ -5062,8 +5059,7 @@ describe('document', function() {
         contact: ContactSchema
       });
 
-      const EmergencyContact =
-        db.model('EmergencyContact', EmergencyContactSchema);
+      const EmergencyContact = db.model('Test', EmergencyContactSchema);
 
       const contact = new EmergencyContact({
         contactName: 'Electrical Service',
@@ -5926,7 +5922,7 @@ describe('document', function() {
         name: String
       }, { strict: false });
 
-      const Model = db.model('prototest', schema);
+      const Model = db.model('Test', schema);
       const doc = new Model({ '__proto__.x': 'foo' });
 
       assert.strictEqual(Model.x, void 0);
@@ -6349,7 +6345,7 @@ describe('document', function() {
           }
         }, { strict: false })
       });
-      const NestedModel = db.model('Nested', NestedSchema);
+      const NestedModel = db.model('Test', NestedSchema);
       const n = new NestedModel({
         parent: {
           name: 'foo',
@@ -8820,6 +8816,8 @@ describe('document', function() {
       age: { type: Number, validate: v => v < 200 }
     });
     const schema = Schema({ nested: nestedSchema });
+
+    mongoose.deleteModel(/Test/);
     const Model = mongoose.model('Test', schema);
 
     const doc = new Model({ nested: { name: 'a', age: 9001 } });
diff --git a/test/es-next/asyncIterator.test.es6.js b/test/es-next/asyncIterator.test.es6.js
index 46cfea1db7b..24cc785a146 100644
--- a/test/es-next/asyncIterator.test.es6.js
+++ b/test/es-next/asyncIterator.test.es6.js
@@ -17,7 +17,9 @@ describe('asyncIterator', function() {
     db = await start();
 
     const schema = new mongoose.Schema({ name: String });
-    Movie = db.model('gh6737_Movie', schema);
+    await db.dropCollection('Movie').catch(() => {});
+    db.deleteModel(/Movie/);
+    Movie = db.model('Movie', schema);
 
     await Movie.create([
       { name: 'Kickboxer' },
diff --git a/test/index.test.js b/test/index.test.js
index e62d17d48ce..a8025689c86 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -661,7 +661,7 @@ describe('mongoose module:', function() {
         it('returns a new uncached model', function(done) {
           const m = new Mongoose;
           const s1 = new Schema({ a: [] });
-          const name = 'non-cached-collection-name';
+          const name = 'Test';
           const A = m.model(name, s1);
           const B = m.model(name);
           const C = m.model(name, 'alternate');
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 08954b5259c..95eb92798d9 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -341,8 +341,8 @@ describe('model', function() {
           }
         });
 
-        const Foo = db.model('Foo', schema);
-        const Bar = Foo.discriminator('Bar', new mongoose.Schema({
+        const Foo = db.model('Test', schema);
+        const Bar = Foo.discriminator('TestDiscriminator', new mongoose.Schema({
           bar: String
         }));
 
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 7c0643f61df..25349b5ce1c 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -215,12 +215,12 @@ describe('model', function() {
 
     it('throws error if model name is taken (gh-4148)', function(done) {
       var Foo = db.model('Test1', new Schema({}));
-      db.model('Bar', new Schema({}));
+      db.model('Test', new Schema({}));
       assert.throws(
         function() {
-          Foo.discriminator('Bar', new Schema());
+          Foo.discriminator('Test', new Schema());
         },
-        /Cannot overwrite `Bar`/);
+        /Cannot overwrite `Test`/);
       done();
     });
 
@@ -1310,7 +1310,8 @@ describe('model', function() {
         autoCreate: false
       });
       schema.plugin(plugin);
-      const model = mongoose.model('Model', schema);
+      mongoose.deleteModel(/Test/);
+      const model = mongoose.model('Test', schema);
 
       const discriminator = model.discriminator('Desc', new Schema({ anotherValue: String }));
 
diff --git a/test/object.create.null.test.js b/test/object.create.null.test.js
index 3b3bb1c9f3d..155014c54d2 100644
--- a/test/object.create.null.test.js
+++ b/test/object.create.null.test.js
@@ -31,7 +31,7 @@ describe('is compatible with object created using Object.create(null) (gh-1484)'
 
   before(function() {
     db = start();
-    M = db.model('1484', schema);
+    M = db.model('Test', schema);
   });
 
   after(function(done) {
diff --git a/test/plugin.idGetter.test.js b/test/plugin.idGetter.test.js
index cb13a10c2da..cb00f2deb17 100644
--- a/test/plugin.idGetter.test.js
+++ b/test/plugin.idGetter.test.js
@@ -22,10 +22,13 @@ describe('id virtual getter', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('should work as expected with an ObjectId', function(done) {
     const schema = new Schema({});
 
-    const S = db.model('Basic', schema);
+    const S = db.model('Test', schema);
     S.create({}, function(err, s) {
       assert.ifError(err);
 
@@ -38,7 +41,7 @@ describe('id virtual getter', function() {
   it('should be turned off when `id` option is set to false', function(done) {
     const schema = new Schema({}, { id: false });
 
-    const S = db.model('NoIdGetter', schema);
+    const S = db.model('Test', schema);
     S.create({}, function(err, s) {
       assert.ifError(err);
 
@@ -54,7 +57,7 @@ describe('id virtual getter', function() {
       id: String
     });
 
-    const S = db.model('SchemaHasId', schema);
+    const S = db.model('Test', schema);
     S.create({ id: 'test' }, function(err, s) {
       assert.ifError(err);
 
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 6f1741dc6e7..9bde285ebab 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -25,7 +25,6 @@ describe('QueryCursor', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => require('./util').clearTestData(db));
 
   beforeEach(function() {
diff --git a/test/query.toconstructor.test.js b/test/query.toconstructor.test.js
index 05e2e9a2ffc..41e03bd5a22 100644
--- a/test/query.toconstructor.test.js
+++ b/test/query.toconstructor.test.js
@@ -5,7 +5,6 @@ const start = require('./common');
 const Query = require('../lib/query');
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -13,28 +12,6 @@ const Schema = mongoose.Schema;
 describe('Query:', function() {
   let Comment;
   let Product;
-  let prodName;
-  let cName;
-
-  before(function() {
-    Comment = new Schema({
-      text: String
-    });
-
-    Product = new Schema({
-      tags: {}, // mixed
-      array: Array,
-      ids: [Schema.ObjectId],
-      strings: [String],
-      numbers: [Number],
-      comments: [Comment],
-      title: String
-    });
-    prodName = 'Product' + random();
-    mongoose.model(prodName, Product);
-    cName = 'Comment' + random();
-    mongoose.model(cName, Comment);
-  });
 
   describe('toConstructor', function() {
     let db;
@@ -47,8 +24,24 @@ describe('Query:', function() {
       db.close(done);
     });
 
+    before(function() {
+      Comment = new Schema({
+        text: String
+      });
+
+      Product = new Schema({
+        tags: {}, // mixed
+        array: Array,
+        ids: [Schema.ObjectId],
+        strings: [String],
+        numbers: [Number],
+        comments: [Comment],
+        title: String
+      });
+      Product = db.model('Product', Product);
+    });
+
     it('creates a query', function(done) {
-      const Product = db.model(prodName);
       const prodQ = Product.find({ title: /test/ }).toConstructor();
 
       assert.ok(prodQ() instanceof Query);
@@ -56,8 +49,6 @@ describe('Query:', function() {
     });
 
     it('copies all the right values', function(done) {
-      const Product = db.model(prodName);
-
       const prodQ = Product.update({ title: /test/ }, { title: 'blah' });
 
       const prodC = prodQ.toConstructor();
@@ -75,7 +66,6 @@ describe('Query:', function() {
     });
 
     it('gets expected results', function(done) {
-      const Product = db.model(prodName);
       Product.create({ title: 'this is a test' }, function(err, p) {
         assert.ifError(err);
         const prodC = Product.find({ title: /test/ }).toConstructor();
@@ -90,8 +80,6 @@ describe('Query:', function() {
     });
 
     it('can be re-used multiple times', function(done) {
-      const Product = db.model(prodName);
-
       Product.create([{ title: 'moar thing' }, { title: 'second thing' }], function(err, prods) {
         assert.ifError(err);
         assert.equal(prods.length, 2);
@@ -117,8 +105,6 @@ describe('Query:', function() {
     });
 
     it('options get merged properly', function(done) {
-      const Product = db.model(prodName);
-
       let prodC = Product.find({ title: /blah/ }).setOptions({ sort: 'title', lean: true });
       prodC = prodC.toConstructor();
 
@@ -132,8 +118,6 @@ describe('Query:', function() {
     });
 
     it('options get cloned (gh-3176)', function(done) {
-      const Product = db.model(prodName);
-
       let prodC = Product.find({ title: /blah/ }).setOptions({ sort: 'title', lean: true });
       prodC = prodC.toConstructor();
 
@@ -151,8 +135,6 @@ describe('Query:', function() {
     });
 
     it('creates subclasses of mquery', function(done) {
-      const Product = db.model(prodName);
-
       const opts = { safe: { w: 'majority' }, readPreference: 'p' };
       const match = { title: 'test', count: { $gt: 101 } };
       const select = { name: 1, count: 0 };
@@ -179,8 +161,6 @@ describe('Query:', function() {
     });
 
     it('with findOneAndUpdate (gh-4318)', function(done) {
-      const Product = db.model(prodName);
-
       const Q = Product.where({ title: 'test' }).toConstructor();
 
       const query = { 'tags.test': 1 };
@@ -204,7 +184,7 @@ describe('Query:', function() {
         called++;
       });
 
-      const Test = db.model('gh6455', schema);
+      const Test = db.model('Test', schema);
       const test = new Test({ name: 'Romero' });
       const Q = Test.findOne({}).toConstructor();
 
@@ -217,7 +197,8 @@ describe('Query:', function() {
     });
 
     it('works with entries-style sort() syntax (gh-8159)', function() {
-      const Model = mongoose.model('gh8159', Schema({ name: String }));
+      mongoose.deleteModel(/Test/);
+      const Model = mongoose.model('Test', Schema({ name: String }));
 
       const query = Model.find().sort([['name', 1]]);
       const Query = query.toConstructor();
diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index b2feeb0854e..8df245437b1 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -23,6 +23,9 @@ describe('schema alias option', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('works with all basic schema types', function(done) {
     const schema = new Schema({
       string: { type: String, alias: 'StringAlias' },
@@ -35,7 +38,7 @@ describe('schema alias option', function() {
       array: { type: [], alias: 'ArrayAlias' }
     });
 
-    const S = db.model('AliasSchemaType', schema);
+    const S = db.model('Test', schema);
     S.create({
       string: 'hello',
       number: 1,
@@ -75,7 +78,7 @@ describe('schema alias option', function() {
       }
     });
 
-    const S = db.model('AliasNestedSchemaType', schema);
+    const S = db.model('Test', schema);
     S.create({
       nested: {
         string: 'hello',
@@ -141,7 +144,8 @@ describe('schema alias option', function() {
       }
     });
     // acquit:ignore:start
-    const Parent = mongoose.model('gh6671', parentSchema);
+    mongoose.deleteModel(/Test/);
+    const Parent = mongoose.model('Test', parentSchema);
     const doc = new Parent({
       c: {
         name: 'foo'
diff --git a/test/schema.boolean.test.js b/test/schema.boolean.test.js
index 682d8932760..58963bd62dc 100644
--- a/test/schema.boolean.test.js
+++ b/test/schema.boolean.test.js
@@ -12,24 +12,15 @@ const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
 describe('schematype', function() {
-  let db;
-
-  before(function() {
-    db = start();
-  });
-
-  after(function(done) {
-    db.close(done);
-  });
-
   describe('boolean', function() {
     it('null default is permitted (gh-523)', function(done) {
+      mongoose.deleteModel(/Test/);
       const s1 = new Schema({ b: { type: Boolean, default: null } });
-      const M1 = db.model('NullDateDefaultIsAllowed1', s1);
+      const M1 = mongoose.model('Test1', s1);
       const s2 = new Schema({ b: { type: Boolean, default: false } });
-      const M2 = db.model('NullDateDefaultIsAllowed2', s2);
+      const M2 = mongoose.model('Test2', s2);
       const s3 = new Schema({ b: { type: Boolean, default: true } });
-      const M3 = db.model('NullDateDefaultIsAllowed3', s3);
+      const M3 = mongoose.model('Test3', s3);
 
       const m1 = new M1;
       assert.strictEqual(null, m1.b);
@@ -39,56 +30,5 @@ describe('schematype', function() {
       assert.strictEqual(true, m3.b);
       done();
     });
-
-    it('strictBool option (gh-5211)', function(done) {
-      const s1 = new Schema({ b: { type: Boolean } });
-      const M1 = db.model('StrictBoolOption', s1);
-
-      const strictValues = [true, false, 'true', 'false', 0, 1, '0', '1', 'no', 'yes'];
-
-      let testsRemaining = strictValues.length;
-      strictValues.forEach(function(value) {
-        const doc = new M1;
-        doc.b = value;
-        doc.validate(function(error) {
-          if (error) {
-            // test fails as soon as one value fails
-            return done(error);
-          }
-          if (!--testsRemaining) {
-            return done();
-          }
-        });
-      });
-    });
-
-    it('strictBool schema option', function(done) {
-      const s1 = new Schema({ b: { type: Boolean } }, { strictBool: true });
-      const M1 = db.model('StrictBoolTrue', s1);
-
-      const strictValues = [true, false, 'true', 'false', 0, 1, '0', '1'];
-
-      strictValues.forEach(function(value) {
-        const doc = new M1;
-        doc.b = value;
-        doc.validate(function(error) {
-          if (error) {
-            // test fails as soon as one value fails
-            return done(error);
-          }
-        });
-      });
-
-      const doc = new M1;
-      doc.b = 'Not a boolean';
-      doc.validate(function(error) {
-        if (error) {
-          done();
-        } else {
-          done(new Error('ValidationError expected'));
-        }
-      });
-    });
-
   });
 });
diff --git a/test/schema.date.test.js b/test/schema.date.test.js
index 227786469a7..2014f4779c8 100644
--- a/test/schema.date.test.js
+++ b/test/schema.date.test.js
@@ -12,7 +12,8 @@ describe('SchemaDate', function() {
 
   before(function() {
     const schema = new Schema({ x: Date });
-    M = mongoose.model('Model', schema);
+    mongoose.deleteModel(/Test/);
+    M = mongoose.model('Test', schema);
   });
 
   it('accepts a Date', function() {
diff --git a/test/schema.onthefly.test.js b/test/schema.onthefly.test.js
index b8b73a18ce2..5d5afec1952 100644
--- a/test/schema.onthefly.test.js
+++ b/test/schema.onthefly.test.js
@@ -3,7 +3,6 @@
 const start = require('./common');
 
 const assert = require('assert');
-const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -11,7 +10,6 @@ const ObjectId = Schema.ObjectId;
 
 describe('schema.onthefly', function() {
   let DecoratedSchema;
-  let collection;
   let db;
 
   before(function() {
@@ -19,18 +17,18 @@ describe('schema.onthefly', function() {
       title: String
     }, { strict: false });
 
-    mongoose.model('Decorated', DecoratedSchema);
     db = start();
-
-    collection = 'decorated_' + random();
   });
 
   after(function(done) {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('setting should cache the schema type and cast values appropriately', function(done) {
-    const Decorated = db.model('Decorated', collection);
+    const Decorated = db.model('Test', DecoratedSchema);
 
     const post = new Decorated();
     post.set('adhoc', '9', Number);
@@ -39,7 +37,7 @@ describe('schema.onthefly', function() {
   });
 
   it('should be local to the particular document', function(done) {
-    const Decorated = db.model('Decorated', collection);
+    const Decorated = db.model('Test', DecoratedSchema);
 
     const postOne = new Decorated();
     postOne.set('adhoc', '9', Number);
@@ -52,7 +50,7 @@ describe('schema.onthefly', function() {
   });
 
   it('querying a document that had an on the fly schema should work', function(done) {
-    const Decorated = db.model('Decorated', collection);
+    const Decorated = db.model('Test', DecoratedSchema);
 
     const post = new Decorated({ title: 'AD HOC' });
     // Interpret adhoc as a Number
@@ -89,7 +87,7 @@ describe('schema.onthefly', function() {
   });
 
   it('on the fly Embedded Array schemas should cast properly', function(done) {
-    const Decorated = db.model('Decorated', collection);
+    const Decorated = db.model('Test', DecoratedSchema);
 
     const post = new Decorated();
     post.set('moderators', [{ name: 'alex trebek' }], [new Schema({ name: String })]);
@@ -98,7 +96,7 @@ describe('schema.onthefly', function() {
   });
 
   it('on the fly Embedded Array schemas should get from a fresh queried document properly', function(done) {
-    const Decorated = db.model('Decorated', collection);
+    const Decorated = db.model('Test', DecoratedSchema);
 
     const post = new Decorated();
     const ModeratorSchema = new Schema({ name: String, ranking: Number });
@@ -124,7 +122,7 @@ describe('schema.onthefly', function() {
   });
 
   it('casts on get() (gh-2360)', function(done) {
-    const Decorated = db.model('gh2360', DecoratedSchema, 'gh2360');
+    const Decorated = db.model('Test', DecoratedSchema);
 
     const d = new Decorated({ title: '1' });
     assert.equal(typeof d.get('title', Number), 'number');
diff --git a/test/schema.select.test.js b/test/schema.select.test.js
index 410ec78877b..bc9a405f822 100644
--- a/test/schema.select.test.js
+++ b/test/schema.select.test.js
@@ -8,8 +8,6 @@ const start = require('./common');
 
 const assert = require('assert');
 const co = require('co');
-const random = require('../lib/utils').random;
-
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
@@ -24,6 +22,9 @@ describe('schema select option', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('excluding paths through schematype', function(done) {
     const schema = new Schema({
       thin: Boolean,
@@ -31,7 +32,7 @@ describe('schema select option', function() {
       docs: [new Schema({ bool: Boolean, name: { type: String, select: false } })]
     });
 
-    const S = db.model('ExcludingBySchemaType', schema);
+    const S = db.model('Test', schema);
     S.create({ thin: true, name: 'the excluded', docs: [{ bool: true, name: 'test' }] }, function(err, s) {
       assert.ifError(err);
       assert.equal(s.name, 'the excluded');
@@ -73,7 +74,7 @@ describe('schema select option', function() {
       docs: [new Schema({ bool: Boolean, name: { type: String, select: true } })]
     });
 
-    const S = db.model('IncludingBySchemaType', schema);
+    const S = db.model('Test', schema);
     S.create({ thin: true, name: 'the included', docs: [{ bool: true, name: 'test' }] }, function(err, s) {
       assert.ifError(err);
       assert.equal(s.name, 'the included');
@@ -125,8 +126,8 @@ describe('schema select option', function() {
         docs: [new Schema({ name: { type: String, select: false }, bool: Boolean })]
       });
 
-      S = db.model('OverriddingSelectedBySchemaType', selected);
-      E = db.model('OverriddingExcludedBySchemaType', excluded);
+      S = db.model('Test1', selected);
+      E = db.model('Test2', excluded);
     });
 
     describe('works', function() {
@@ -284,7 +285,7 @@ describe('schema select option', function() {
       const selected = new Schema({
         docs: { type: [child], select: false }
       });
-      const M = m.model('gh-1333-deselect', selected);
+      const M = m.model('Test', selected);
 
       const query = M.findOne();
       query._applyPaths();
@@ -305,7 +306,7 @@ describe('schema select option', function() {
           docs: { type: [child], select: false }
         }
       });
-      const M = db.model('gh7945', selected);
+      const M = db.model('Test', selected);
 
       const query = M.findOne();
       query._applyPaths();
@@ -330,7 +331,7 @@ describe('schema select option', function() {
         docs: [new Schema({ name: { type: String, select: false }, bool: Boolean })]
       });
 
-      const M = db.model('ForcedInclusionOfPath', excluded);
+      const M = db.model('Test', excluded);
       M.create({ thin: false, name: '1 meter', docs: [{ name: 'test', bool: false }] }, function(err, d) {
         assert.ifError(err);
 
@@ -382,7 +383,7 @@ describe('schema select option', function() {
     });
 
     it('works with query.slice (gh-1370)', function(done) {
-      const M = db.model('1370', new Schema({ many: { type: [String], select: false } }));
+      const M = db.model('Test', new Schema({ many: { type: [String], select: false } }));
 
       M.create({ many: ['1', '2', '3', '4', '5'] }, function(err) {
         if (err) {
@@ -402,7 +403,7 @@ describe('schema select option', function() {
     });
 
     it('ignores if path does not have select in schema (gh-6785)', function() {
-      const M = db.model('gh6785', new Schema({
+      const M = db.model('Test', new Schema({
         a: String,
         b: String
       }));
@@ -417,14 +418,14 @@ describe('schema select option', function() {
     });
 
     it('omits if not in schema (gh-7017)', function() {
-      const M = db.model('gh7017', new Schema({
+      const M = db.model('Test', new Schema({
         a: { type: String, select: false },
         b: { type: String, select: false }
-      }), 'gh7017');
+      }), 'Test');
 
       return co(function*() {
         yield db.$initialConnection;
-        yield db.collection('gh7017').insertOne({
+        yield db.collection('Test').insertOne({
           a: 'foo',
           b: 'bar',
           c: 'baz'
@@ -448,7 +449,7 @@ describe('schema select option', function() {
       conflict: { type: String, select: false }
     });
 
-    const S = db.model('ConflictingBySchemaType', schema);
+    const S = db.model('Test', schema);
     S.create({ thin: true, name: 'bing', conflict: 'crosby' }, function(err, s) {
       assert.strictEqual(null, err);
       assert.equal(s.name, 'bing');
@@ -478,7 +479,7 @@ describe('schema select option', function() {
       name: { type: String, select: false }
     });
 
-    const M = db.model('SelectingOnly_idWithExcludedSchemaType', schema);
+    const M = db.model('Test', schema);
     M.find().select('_id -name').exec(function(err) {
       assert.ok(err instanceof Error, 'conflicting path selection error should be instance of Error');
 
@@ -494,7 +495,7 @@ describe('schema select option', function() {
       docs: [new Schema({ name: { type: String, select: false } })]
     });
 
-    const M = db.model('SelectingOnly_idWithExcludedSchemaTypeSubDoc', schema);
+    const M = db.model('Test', schema);
     M.find().select('_id -docs.name').exec(function(err) {
       assert.ok(err instanceof Error, 'conflicting path selection error should be instance of Error');
 
@@ -506,25 +507,25 @@ describe('schema select option', function() {
   });
 
   it('all inclusive/exclusive combos work', function(done) {
-    const coll = 'inclusiveexclusivecomboswork_' + random();
+    const coll = 'Test';
 
     const schema = new Schema({
       name: { type: String },
       age: Number
     }, { collection: coll });
-    const M = db.model('InclusiveExclusiveCombosWork', schema);
+    const M = db.model('Test1', schema);
 
     const schema1 = new Schema({
       name: { type: String, select: false },
       age: Number
     }, { collection: coll });
-    const S = db.model('InclusiveExclusiveCombosWorkWithSchemaSelectionFalse', schema1);
+    const S = db.model('Test2', schema1);
 
     const schema2 = new Schema({
       name: { type: String, select: true },
       age: Number
     }, { collection: coll });
-    const T = db.model('InclusiveExclusiveCombosWorkWithSchemaSelectionTrue', schema2);
+    const T = db.model('Test3', schema2);
 
     function useId(M, id, cb) {
       M.findOne().select('_id -name').exec(function(err, d) {
@@ -606,7 +607,7 @@ describe('schema select option', function() {
       }
     });
 
-    const User = db.model('gh4707', userSchema);
+    const User = db.model('Test', userSchema);
 
     const obj = {
       name: 'Val',
@@ -665,7 +666,7 @@ describe('schema select option', function() {
       }
     });
 
-    const Model = db.model('nested', NestedSchema);
+    const Model = db.model('Test', NestedSchema);
 
     const doc = new Model();
     doc.nested.name = undefined;
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index 2f3c37ab093..de7d321eff8 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -127,6 +127,7 @@ describe('schema options.timestamps', function() {
         timestamps: true
       });
 
+      conn.deleteModel(/Test/);
       const Test = conn.model('Test', TestSchema);
 
       Test.create({
@@ -269,11 +270,13 @@ describe('schema options.timestamps', function() {
         }
       });
 
-      const Cat = conn.model('gh6381', CatSchema);
+      conn.deleteModel(/Test/);
+      const Cat = conn.model('Test', CatSchema);
 
       const d = new Date('2011-06-01');
 
       return co(function*() {
+        yield Cat.deleteMany({});
         yield Cat.insertMany([{ name: 'a' }, { name: 'b', createdAt: d }]);
 
         const cats = yield Cat.find().sort('name');
@@ -324,7 +327,8 @@ describe('schema options.timestamps', function() {
         cats: [CatSchema]
       });
 
-      const Group = conn.model('gh4049', GroupSchema);
+      conn.deleteModel(/Test/);
+      const Group = conn.model('Test', GroupSchema);
       const now = Date.now();
       Group.create({ cats: [{ name: 'Garfield' }] }, function(error, group) {
         assert.ifError(error);
@@ -339,7 +343,8 @@ describe('schema options.timestamps', function() {
         cats: [CatSchema]
       });
 
-      const Group = conn.model('gh4049_0', GroupSchema);
+      conn.deleteModel(/Test/);
+      const Group = conn.model('Test', GroupSchema);
       const now = Date.now();
       Group.create({ cats: [{ name: 'Garfield' }] }, function(error, group) {
         assert.ifError(error);
@@ -367,7 +372,8 @@ describe('schema options.timestamps', function() {
       updatedAt: Number,
       name: String
     }, { timestamps: true });
-    const Model = conn.model('gh3957', schema);
+    conn.deleteModel(/Test/);
+    const Model = conn.model('Test', schema);
     const start = Date.now();
 
     return co(function*() {
@@ -388,7 +394,8 @@ describe('schema options.timestamps', function() {
     }, {
       timestamps: { currentTime: () => 42 }
     });
-    const Model = conn.model('gh3957_0', schema);
+    conn.deleteModel(/Test/);
+    const Model = conn.model('Test', schema);
 
     return co(function*() {
       const doc = yield Model.create({ name: 'test' });
diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index 52b6f38f4fe..faa88d76c17 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -19,6 +19,9 @@ describe('timestamps', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('does not override timestamp params defined in schema (gh-4868)', function(done) {
     const startTime = Date.now();
     const schema = new mongoose.Schema({
@@ -32,7 +35,7 @@ describe('timestamps', function() {
       },
       name: String
     }, { timestamps: true });
-    const M = db.model('gh4868', schema);
+    const M = db.model('Test', schema);
 
     M.create({ name: 'Test' }, function(error) {
       assert.ifError(error);
@@ -51,7 +54,7 @@ describe('timestamps', function() {
     const schema = new mongoose.Schema({
       name: String
     }, { timestamps: { createdAt: null, updatedAt: true } });
-    const M = db.model('gh5598', schema);
+    const M = db.model('Test', schema);
 
     M.create({ name: 'Test' }, function(error) {
       assert.ifError(error);
@@ -73,7 +76,7 @@ describe('timestamps', function() {
     const parentSchema = new mongoose.Schema({
       child: schema
     });
-    const M = db.model('gh5598_0', parentSchema);
+    const M = db.model('Test', parentSchema);
 
     M.create({ child: { name: 'test' } }, function(error) {
       assert.ifError(error);
@@ -92,7 +95,7 @@ describe('timestamps', function() {
     const schema = new mongoose.Schema({
       name: String
     }, { timestamps: { createdAt: 'ts.c', updatedAt: 'ts.a' } });
-    const M = db.model('gh4503', schema);
+    const M = db.model('Test', schema);
 
     M.create({ name: 'Test' }, function(error) {
       assert.ifError(error);
@@ -122,7 +125,7 @@ describe('timestamps', function() {
       },
       name: String
     }, { timestamps: { createdAt: 'ts.createdAt', updatedAt: 'ts.updatedAt' } });
-    const M = db.model('gh4868_0', schema);
+    const M = db.model('Test', schema);
 
     M.create({ name: 'Test' }, function(error) {
       assert.ifError(error);
@@ -152,7 +155,7 @@ describe('timestamps', function() {
       ts: tsSchema,
       name: String
     }, { timestamps: { createdAt: 'ts.createdAt', updatedAt: 'ts.updatedAt' } });
-    const M = db.model('gh4868_1', schema);
+    const M = db.model('Test', schema);
 
     M.create({ name: 'Test' }, function(error) {
       assert.ifError(error);
@@ -170,7 +173,7 @@ describe('timestamps', function() {
     const subSchema = new Schema({}, { timestamps: false });
     const schema = new Schema({ sub: subSchema }, { timestamps: false });
 
-    const Test = db.model('gh7202', schema);
+    const Test = db.model('Test', schema);
     const test = new Test({ sub: {} });
 
     test.save((err, saved) => {
@@ -195,7 +198,7 @@ describe('timestamps', function() {
       }
     }, { timestamps: true });
 
-    const Model = db.model('gh7496', modelSchema);
+    const Model = db.model('Test', modelSchema);
 
     const start = new Date();
     return Model.create({}).then(doc => {
@@ -212,7 +215,7 @@ describe('timestamps', function() {
       ++called;
       return mongoose.Model.updateOne.apply(this, arguments);
     };
-    const M = db.model('gh7698', schema);
+    const M = db.model('Test', schema);
 
     const startTime = Date.now();
     return M.updateOne({}, { name: 'foo' }, { upsert: true }).
@@ -225,8 +228,8 @@ describe('timestamps', function() {
     const childSchema = new mongoose.Schema({ name: String }, {
       timestamps: true
     });
-    const M1 = db.model('gh7712', new mongoose.Schema({ child: childSchema }));
-    const M2 = db.model('gh7712_1', new mongoose.Schema({
+    const M1 = db.model('Test', new mongoose.Schema({ child: childSchema }));
+    const M2 = db.model('Test1', new mongoose.Schema({
       children: [childSchema]
     }));
 
@@ -258,7 +261,7 @@ describe('timestamps', function() {
     const sub = Schema({ name: String }, { timestamps: false, _id: false });
     const schema = Schema({ data: sub });
 
-    const Model = db.model('gh8007', schema);
+    const Model = db.model('Test', schema);
 
     return co(function*() {
       let res = yield Model.create({ data: {} });
@@ -282,7 +285,7 @@ describe('timestamps', function() {
   });
 
   it('updates updatedAt when calling update without $set (gh-4768)', function() {
-    const Model = db.model('gh4768', Schema({ name: String }, { timestamps: true }));
+    const Model = db.model('Test', Schema({ name: String }, { timestamps: true }));
 
     return co(function*() {
       let doc = yield Model.create({ name: 'test1' });
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index b391ae6e8d6..4312295cb40 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -52,6 +52,9 @@ describe('types.buffer', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('test that a mongoose buffer behaves and quacks like a buffer', function(done) {
     let a = new MongooseBuffer;
 
@@ -72,7 +75,7 @@ describe('types.buffer', function() {
   });
 
   it('buffer validation', function(done) {
-    const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
+    const User = db.model('Test', UserBuffer);
 
     User.on('index', function() {
       const t = new User({
@@ -115,7 +118,7 @@ describe('types.buffer', function() {
   });
 
   it('buffer storage', function(done) {
-    const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
+    const User = db.model('Test', UserBuffer);
 
     User.on('index', function() {
       const sampleBuffer = Buffer.from([123, 223, 23, 42, 11]);
@@ -144,7 +147,7 @@ describe('types.buffer', function() {
   });
 
   it('test write markModified', function(done) {
-    const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
+    const User = db.model('Test', UserBuffer);
 
     User.on('index', function() {
       const sampleBuffer = Buffer.from([123, 223, 23, 42, 11]);
@@ -373,7 +376,7 @@ describe('types.buffer', function() {
   });
 
   it('can be set to null', function(done) {
-    const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
+    const User = db.model('Test', UserBuffer);
     const user = new User({ array: [null], required: Buffer.alloc(1) });
     user.save(function(err, doc) {
       assert.ifError(err);
@@ -387,7 +390,7 @@ describe('types.buffer', function() {
   });
 
   it('can be updated to null', function(done) {
-    const User = db.model('UserBuffer', UserBuffer, 'usersbuffer_' + random());
+    const User = db.model('Test', UserBuffer);
     const user = new User({ array: [null], required: Buffer.alloc(1), serial: Buffer.alloc(1) });
     user.save(function(err, doc) {
       assert.ifError(err);
@@ -412,9 +415,9 @@ describe('types.buffer', function() {
   describe('subtype', function() {
     let bufferSchema, B;
 
-    before(function(done) {
+    beforeEach(function(done) {
       bufferSchema = new Schema({ buf: Buffer });
-      B = db.model('1571', bufferSchema);
+      B = db.model('Test', bufferSchema);
       done();
     });
 
@@ -485,7 +488,8 @@ describe('types.buffer', function() {
 
     it('cast from number (gh-3764)', function(done) {
       const schema = new Schema({ buf: Buffer });
-      const MyModel = mongoose.model('gh3764', schema);
+      mongoose.deleteModel(/Test/);
+      const MyModel = mongoose.model('Test', schema);
 
       const doc = new MyModel({ buf: 9001 });
       assert.equal(doc.buf.length, 1);
@@ -494,7 +498,8 @@ describe('types.buffer', function() {
 
     it('cast from string', function(done) {
       const schema = new Schema({ buf: Buffer });
-      const MyModel = mongoose.model('bufferFromString', schema);
+      mongoose.deleteModel(/Test/);
+      const MyModel = mongoose.model('Test', schema);
 
       const doc = new MyModel({ buf: 'hi' });
       assert.ok(doc.buf instanceof Buffer);
@@ -504,7 +509,8 @@ describe('types.buffer', function() {
 
     it('cast from array', function(done) {
       const schema = new Schema({ buf: Buffer });
-      const MyModel = mongoose.model('bufferFromArray', schema);
+      mongoose.deleteModel(/Test/);
+      const MyModel = mongoose.model('Test', schema);
 
       const doc = new MyModel({ buf: [195, 188, 98, 101, 114] });
       assert.ok(doc.buf instanceof Buffer);
@@ -514,7 +520,8 @@ describe('types.buffer', function() {
 
     it('cast from Binary', function(done) {
       const schema = new Schema({ buf: Buffer });
-      const MyModel = mongoose.model('bufferFromBinary', schema);
+      mongoose.deleteModel(/Test/);
+      const MyModel = mongoose.model('Test', schema);
 
       const doc = new MyModel({ buf: new MongooseBuffer.Binary([228, 189, 160, 229, 165, 189], 0) });
       assert.ok(doc.buf instanceof Buffer);
@@ -524,7 +531,8 @@ describe('types.buffer', function() {
 
     it('cast from json (gh-6863)', function(done) {
       const schema = new Schema({ buf: Buffer });
-      const MyModel = mongoose.model('gh6863', schema);
+      mongoose.deleteModel(/Test/);
+      const MyModel = mongoose.model('Test', schema);
 
       const doc = new MyModel({ buf: { type: 'Buffer', data: [103, 104, 45, 54, 56, 54, 51] } });
       assert.ok(doc.buf instanceof Buffer);
diff --git a/test/types.decimal128.test.js b/test/types.decimal128.test.js
index e226d5195c3..4273f12c0df 100644
--- a/test/types.decimal128.test.js
+++ b/test/types.decimal128.test.js
@@ -33,7 +33,8 @@ describe('types.decimal128', function() {
       value: Schema.Types.Decimal128
     });
 
-    const BigNum = mongoose.model('gh6418', dec128);
+    mongoose.deleteModel(/Test/);
+    const BigNum = mongoose.model('Test', dec128);
 
     const obj = {
       str: '10.123',
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index dd9f0d7ca73..9426bad994b 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -16,7 +16,6 @@ const setValue = require('../lib/utils').setValue;
 const mongoose = require('./common').mongoose;
 const Schema = mongoose.Schema;
 const MongooseDocumentArray = mongoose.Types.DocumentArray;
-const collection = 'types.documentarray_' + random();
 
 /**
  * Setup.
@@ -61,6 +60,9 @@ describe('types.documentarray', function() {
     db.close(done);
   });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
   it('behaves and quacks like an array', function(done) {
     const a = new MongooseDocumentArray();
 
@@ -245,20 +247,12 @@ describe('types.documentarray', function() {
       });
 
       const db = mongoose.createConnection();
-      let M = db.model('gh-1415', { docs: [subSchema] });
+      let M = db.model('Test', { docs: [subSchema] });
       let m = new M;
       m.docs.push({ docs: [{ title: 'hello' }] });
       let delta = m.$__delta()[1];
       assert.equal(delta.$push.docs.$each[0].changed, undefined);
 
-      M = db.model('gh-1415-1', new Schema({ docs: [subSchema] }, {
-        usePushEach: true
-      }));
-      m = new M;
-      m.docs.push({ docs: [{ title: 'hello' }] });
-      delta = m.$__delta()[1];
-      assert.equal(delta.$push.docs.$each[0].changed, undefined);
-
       done();
     });
     it('uses the correct transform (gh-1412)', function(done) {
@@ -282,8 +276,8 @@ describe('types.documentarray', function() {
         }
       });
 
-      const First = db.model('first', FirstSchema);
-      const Second = db.model('second', SecondSchema);
+      const First = db.model('Test', FirstSchema);
+      const Second = db.model('Test1', SecondSchema);
 
       const first = new First({});
 
@@ -306,7 +300,8 @@ describe('types.documentarray', function() {
       assert.equal(typeof a.create, 'function');
 
       const schema = new Schema({ docs: [new Schema({ name: 'string' })] });
-      const T = mongoose.model('embeddedDocument#create_test', schema, 'asdfasdfa' + random());
+      mongoose.deleteModel(/Test/);
+      const T = mongoose.model('Test', schema);
       const t = new T;
       assert.equal(typeof t.docs.create, 'function');
       const subdoc = t.docs.create({ name: 100 });
@@ -325,7 +320,7 @@ describe('types.documentarray', function() {
         next();
       });
       const schema = new Schema({ children: [child] });
-      const M = db.model('embeddedDocArray-push-re-cast', schema, 'edarecast-' + random());
+      const M = db.model('Test', schema, 'edarecast-' + random());
       const m = new M;
       m.save(function(err) {
         assert.ifError(err);
@@ -361,7 +356,7 @@ describe('types.documentarray', function() {
 
     it('corrects #ownerDocument() and index if value was created with array.create() (gh-1385)', function(done) {
       const mg = new mongoose.Mongoose;
-      const M = mg.model('1385', { docs: [{ name: String }] });
+      const M = mg.model('Test', { docs: [{ name: String }] });
       const m = new M;
       const doc = m.docs.create({ name: 'test 1385' });
       assert.equal(String(doc.ownerDocument()._id), String(m._id));
@@ -372,7 +367,7 @@ describe('types.documentarray', function() {
     });
 
     it('corrects #ownerDocument() if value was created with array.create() and set() (gh-7504)', function(done) {
-      const M = db.model('gh7504', {
+      const M = db.model('Test', {
         docs: [{ name: { type: String, validate: () => false } }]
       });
       const m = new M({});
@@ -394,7 +389,8 @@ describe('types.documentarray', function() {
         }]
       });
 
-      const Parent = mongoose.model('gh7724', parentSchema);
+      mongoose.deleteModel(/Test/);
+      const Parent = mongoose.model('Test', parentSchema);
 
       const p = new Parent({
         name: 'Eddard Stark',
@@ -425,7 +421,7 @@ describe('types.documentarray', function() {
       comments: [Comments]
     });
 
-    const Post = db.model('docarray-BlogPost', BlogPost, collection);
+    const Post = db.model('BlogPost', BlogPost);
 
     const p = new Post({ title: 'comment nesting' });
     const c1 = p.comments.create({ title: 'c1' });
@@ -469,7 +465,8 @@ describe('types.documentarray', function() {
         }
       });
 
-      const T = mongoose.model('TopLevelRequired', schema);
+      mongoose.deleteModel(/Test/);
+      const T = mongoose.model('Test', schema);
       const t = new T({});
       t.docs.push({ name: 'test1' });
       t.docs.push({ name: 'test2' });
@@ -491,7 +488,8 @@ describe('types.documentarray', function() {
         }]
       });
 
-      const T = mongoose.model('DocArrayNestedRequired', schema);
+      mongoose.deleteModel(/Test/);
+      const T = mongoose.model('Test', schema);
       const t = new T({});
       t.docs.push(null);
       t.docs.push({ name: 'test2' });
@@ -512,7 +510,8 @@ describe('types.documentarray', function() {
         subdoc.invalidate('name', 'boo boo', '%');
         next();
       });
-      const T = mongoose.model('embeddedDocument#invalidate_test', schema, 'asdfasdfa' + random());
+      mongoose.deleteModel(/Test/);
+      const T = mongoose.model('Test', schema);
       const t = new T;
       t.docs.push({ name: 100 });
 
@@ -536,8 +535,8 @@ describe('types.documentarray', function() {
       const nested = new Schema({ v: { type: Number, max: 30 } });
       const schema = new Schema({
         docs: [nested]
-      }, { collection: 'embedded-invalidate-' + random() });
-      const M = db.model('embedded-invalidate', schema);
+      });
+      const M = db.model('Test', schema);
       const m = new M({ docs: [{ v: 900 }] });
       m.save(function(err) {
         assert.equal(err.errors['docs.0.v'].value, 900);
@@ -550,7 +549,7 @@ describe('types.documentarray', function() {
       const schema = new Schema({
         docs: [nested]
       });
-      const M = db.model('gh6723', schema);
+      const M = db.model('Test', schema);
 
       const m = new M({});
       m.docs = [50];
@@ -565,7 +564,7 @@ describe('types.documentarray', function() {
       const schema = new Schema({
         docs: [nested]
       });
-      const M = db.model('gh8317', schema);
+      const M = db.model('Test', schema);
 
       const doc = M.hydrate({ docs: [{ v: 1 }, { v: 2 }] });
       let arr = doc.docs;
@@ -578,7 +577,8 @@ describe('types.documentarray', function() {
 
     it('map() works', function() {
       const personSchema = new Schema({ friends: [{ name: { type: String } }] });
-      const Person = mongoose.model('gh8317-map', personSchema);
+      mongoose.deleteModel(/Test/);
+      const Person = mongoose.model('Test', personSchema);
 
       const person = new Person({ friends: [{ name: 'Hafez' }] });
 
@@ -590,7 +590,7 @@ describe('types.documentarray', function() {
     });
 
     it('slice() after map() works (gh-8399)', function() {
-      const MyModel = db.model('gh8399', Schema({
+      const MyModel = db.model('Test', Schema({
         myArray: [{ name: String }]
       }));
 
@@ -621,7 +621,7 @@ describe('types.documentarray', function() {
       children: [childSchema]
     });
 
-    const Parent = db.model('gh7249', parentSchema);
+    const Parent = db.model('Test', parentSchema);
 
     return co(function*() {
       let parent = yield Parent.create({
diff --git a/test/types.subdocument.test.js b/test/types.subdocument.test.js
index 51178ebe54e..0407b8005a7 100644
--- a/test/types.subdocument.test.js
+++ b/test/types.subdocument.test.js
@@ -64,7 +64,7 @@ describe('types.subdocument', function() {
   });
 
   it('not setting timestamps in subdocuments', function() {
-    const Thing = db.model('Thing', new Schema({
+    const Thing = db.model('Test', new Schema({
       subArray: [{
         testString: String
       }]
@@ -98,7 +98,7 @@ describe('types.subdocument', function() {
     it('defers to parent isModified (gh-8223)', function() {
       const childSchema = Schema({ id: Number, text: String });
       const parentSchema = Schema({ child: childSchema });
-      const Model = db.model('gh8223', parentSchema);
+      const Model = db.model('Test1', parentSchema);
 
       const doc = new Model({ child: { text: 'foo' } });
       assert.ok(doc.isModified('child.id'));
diff --git a/test/utils.test.js b/test/utils.test.js
index d9af31b15d4..bd4ce2c9073 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -169,15 +169,13 @@ describe('utils', function() {
   });
 
   it('deepEquals on MongooseDocumentArray works', function(done) {
-    const db = start();
     const A = new Schema({ a: String });
-    const M = db.model('deepEqualsOnMongooseDocArray', new Schema({
+    mongoose.deleteModel(/Test/);
+    const M = mongoose.model('Test', new Schema({
       a1: [A],
       a2: [A]
     }));
 
-    db.close();
-
     const m1 = new M({
       a1: [{ a: 'Hi' }, { a: 'Bye' }]
     });
diff --git a/test/versioning.test.js b/test/versioning.test.js
index d04cc496502..bc1c3a3ffbb 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -21,7 +21,16 @@ describe('versioning', function() {
 
   before(function() {
     db = start();
+  });
+
+  after(function(done) {
+    db.close(done);
+  });
 
+  beforeEach(() => db.deleteModel(/.*/));
+  afterEach(() => require('./util').clearTestData(db));
+
+  beforeEach(function() {
     Comments = new Schema();
 
     Comments.add({
@@ -55,22 +64,18 @@ describe('versioning', function() {
         }
       });
 
-    BlogPost = mongoose.model('Versioning', BlogPost).schema;
-  });
-
-  after(function(done) {
-    db.close(done);
+    BlogPost = db.model('BlogPost', BlogPost);
   });
 
   it('is only added to parent schema (gh-1265)', function(done) {
-    assert.ok(BlogPost.path('__v'));
-    assert.ok(!BlogPost.path('comments').__v);
-    assert.ok(!BlogPost.path('meta.nested').__v);
+    assert.ok(BlogPost.schema.path('__v'));
+    assert.ok(!BlogPost.schema.path('comments').__v);
+    assert.ok(!BlogPost.schema.path('meta.nested').__v);
     done();
   });
 
   it('works', function(done) {
-    const V = db.model('Versioning');
+    const V = BlogPost;
 
     const doc = new V;
     doc.title = 'testing versioning';
@@ -331,7 +336,7 @@ describe('versioning', function() {
   });
 
   it('versioning without version key', function(done) {
-    const V = db.model('Versioning');
+    const V = BlogPost;
 
     const doc = new V;
     doc.numbers = [3, 4, 5, 6, 7];
@@ -359,7 +364,8 @@ describe('versioning', function() {
 
   it('version works with strict docs', function(done) {
     const schema = new Schema({ str: ['string'] }, { strict: true, collection: 'versionstrict_' + random() });
-    const M = db.model('VersionStrict', schema);
+    db.deleteModel(/BlogPost/)
+    const M = db.model('BlogPost', schema);
     const m = new M({ str: ['death', 'to', 'smootchy'] });
     m.save(function(err) {
       assert.ifError(err);
@@ -384,7 +390,7 @@ describe('versioning', function() {
   });
 
   it('version works with existing unversioned docs', function(done) {
-    const V = db.model('Versioning');
+    const V = BlogPost;
 
     V.collection.insertOne({ title: 'unversioned', numbers: [1, 2, 3] }, { safe: true }, function(err) {
       assert.ifError(err);
@@ -413,7 +419,7 @@ describe('versioning', function() {
     const schema = new Schema(
       { configured: 'bool' },
       { versionKey: 'lolwat', collection: 'configuredversion' + random() });
-    const V = db.model('ConfiguredVersionKey', schema);
+    const V = db.model('Test', schema);
     const v = new V({ configured: true });
     v.save(function(err) {
       assert.ifError(err);
@@ -427,7 +433,7 @@ describe('versioning', function() {
 
   it('can be disabled', function(done) {
     const schema = new Schema({ x: ['string'] }, { versionKey: false });
-    const M = db.model('disabledVersioning', schema, 's' + random());
+    const M = db.model('Test', schema);
     M.create({ x: ['hi'] }, function(err, doc) {
       assert.ifError(err);
       assert.equal('__v' in doc._doc, false);
@@ -449,7 +455,7 @@ describe('versioning', function() {
   });
 
   it('works with numbericAlpha paths', function(done) {
-    const M = db.model('Versioning');
+    const M = BlogPost;
     const m = new M({ mixed: {} });
     const path = 'mixed.4a';
     m.set(path, 2);
@@ -461,7 +467,7 @@ describe('versioning', function() {
 
   describe('doc.increment()', function() {
     it('works without any other changes (gh-1475)', function(done) {
-      const V = db.model('Versioning');
+      const V = BlogPost;
 
       const doc = new V;
       doc.save(function(err) {
@@ -501,7 +507,7 @@ describe('versioning', function() {
   it('gh-1898', function(done) {
     const schema = new Schema({ tags: [String], name: String });
 
-    const M = db.model('gh-1898', schema, 'gh-1898');
+    const M = db.model('Test', schema);
 
     const m = new M({ tags: ['eggs'] });
 
@@ -521,7 +527,7 @@ describe('versioning', function() {
 
   it('can remove version key from toObject() (gh-2675)', function(done) {
     const schema = new Schema({ name: String });
-    const M = db.model('gh2675', schema, 'gh2675');
+    const M = db.model('Test', schema);
 
     const m = new M();
     m.save(function(err, m) {
@@ -535,7 +541,7 @@ describe('versioning', function() {
   });
 
   it('pull doesnt add version where clause (gh-6190)', function() {
-    const User = db.model('gh6190_User', new mongoose.Schema({
+    const User = db.model('User', new mongoose.Schema({
       unreadPosts: [{ type: mongoose.Schema.Types.ObjectId }]
     }));
 
@@ -562,7 +568,7 @@ describe('versioning', function() {
 
   it('copying doc works (gh-5779)', function(done) {
     const schema = new Schema({ subdocs: [{ a: Number }] });
-    const M = db.model('gh5779', schema, 'gh5779');
+    const M = db.model('Test', schema);
     const m = new M({ subdocs: [] });
     let m2;
 

From 105c8ae79065fd749556518f600c3cfa9d1ad8f7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Mar 2020 21:19:50 -0400
Subject: [PATCH 0624/2348] test: fix tests re: #8481

---
 test/timestamps.test.js          | 4 ++--
 test/types.buffer.test.js        | 3 +--
 test/types.documentarray.test.js | 6 +++---
 test/versioning.test.js          | 2 +-
 4 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index faa88d76c17..4ef50302fe7 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -127,9 +127,9 @@ describe('timestamps', function() {
     }, { timestamps: { createdAt: 'ts.createdAt', updatedAt: 'ts.updatedAt' } });
     const M = db.model('Test', schema);
 
-    M.create({ name: 'Test' }, function(error) {
+    M.create({ name: 'Test' }, function(error, doc) {
       assert.ifError(error);
-      M.findOne({}, function(error, doc) {
+      M.findOne({ _id: doc._id }, function(error, doc) {
         assert.ifError(error);
         assert.ok(!doc.ts.createdAt);
         assert.ok(doc.ts.updatedAt);
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index 4312295cb40..535eb087674 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -9,7 +9,6 @@ const start = require('./common');
 const Buffer = require('safe-buffer').Buffer;
 const assert = require('assert');
 const mongoose = require('./common').mongoose;
-const random = require('../lib/utils').random;
 
 const MongooseBuffer = mongoose.Types.Buffer;
 const Schema = mongoose.Schema;
@@ -83,7 +82,7 @@ describe('types.buffer', function() {
       });
 
       t.validate(function(err) {
-        assert.ok(err.message.indexOf('UserBuffer validation failed') === 0, err.message);
+        assert.ok(err.message.indexOf('Test validation failed') === 0, err.message);
         assert.equal(err.errors.required.kind, 'required');
         t.required = { x: [20] };
         t.save(function(err) {
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 9426bad994b..8b3499cc6de 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -247,10 +247,10 @@ describe('types.documentarray', function() {
       });
 
       const db = mongoose.createConnection();
-      let M = db.model('Test', { docs: [subSchema] });
-      let m = new M;
+      const M = db.model('Test', { docs: [subSchema] });
+      const m = new M;
       m.docs.push({ docs: [{ title: 'hello' }] });
-      let delta = m.$__delta()[1];
+      const delta = m.$__delta()[1];
       assert.equal(delta.$push.docs.$each[0].changed, undefined);
 
       done();
diff --git a/test/versioning.test.js b/test/versioning.test.js
index bc1c3a3ffbb..bc630056dde 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -364,7 +364,7 @@ describe('versioning', function() {
 
   it('version works with strict docs', function(done) {
     const schema = new Schema({ str: ['string'] }, { strict: true, collection: 'versionstrict_' + random() });
-    db.deleteModel(/BlogPost/)
+    db.deleteModel(/BlogPost/);
     const M = db.model('BlogPost', schema);
     const m = new M({ str: ['death', 'to', 'smootchy'] });
     m.save(function(err) {

From c41ae4d6bdccd18a2779a5e1f7670df833b177f2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Mar 2020 21:26:01 -0400
Subject: [PATCH 0625/2348] test: fix more tests re: #8481

---
 test/timestamps.test.js   | 23 ++++++++++++-----------
 test/types.buffer.test.js |  4 ++--
 2 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index 4ef50302fe7..b54507cb0f6 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -37,9 +37,9 @@ describe('timestamps', function() {
     }, { timestamps: true });
     const M = db.model('Test', schema);
 
-    M.create({ name: 'Test' }, function(error) {
+    M.create({ name: 'Test' }, function(error, doc) {
       assert.ifError(error);
-      M.findOne({}, function(error, doc) {
+      M.findOne({ _id: doc._id }, function(error, doc) {
         assert.ifError(error);
         assert.ok(!doc.createdAt);
         assert.ok(doc.updatedAt);
@@ -56,9 +56,9 @@ describe('timestamps', function() {
     }, { timestamps: { createdAt: null, updatedAt: true } });
     const M = db.model('Test', schema);
 
-    M.create({ name: 'Test' }, function(error) {
+    M.create({ name: 'Test' }, function(error, doc) {
       assert.ifError(error);
-      M.findOne({}, function(error, doc) {
+      M.findOne({ _id: doc._id }, function(error, doc) {
         assert.ifError(error);
         assert.ok(!doc.createdAt);
         assert.ok(doc.updatedAt);
@@ -78,9 +78,9 @@ describe('timestamps', function() {
     });
     const M = db.model('Test', parentSchema);
 
-    M.create({ child: { name: 'test' } }, function(error) {
+    M.create({ child: { name: 'test' } }, function(error, doc) {
       assert.ifError(error);
-      M.findOne({}, function(error, doc) {
+      M.findOne({ _id: doc._id }, function(error, doc) {
         assert.ifError(error);
         assert.ok(!doc.child.createdAt);
         assert.ok(doc.child.updatedAt);
@@ -97,9 +97,9 @@ describe('timestamps', function() {
     }, { timestamps: { createdAt: 'ts.c', updatedAt: 'ts.a' } });
     const M = db.model('Test', schema);
 
-    M.create({ name: 'Test' }, function(error) {
+    M.create({ name: 'Test' }, function(error, doc) {
       assert.ifError(error);
-      M.findOne({}, function(error, doc) {
+      M.findOne({ _id: doc._id }, function(error, doc) {
         assert.ifError(error);
         assert.ok(doc.ts.c);
         assert.ok(doc.ts.c.valueOf() >= startTime);
@@ -157,9 +157,9 @@ describe('timestamps', function() {
     }, { timestamps: { createdAt: 'ts.createdAt', updatedAt: 'ts.updatedAt' } });
     const M = db.model('Test', schema);
 
-    M.create({ name: 'Test' }, function(error) {
+    M.create({ name: 'Test' }, function(error, doc) {
       assert.ifError(error);
-      M.findOne({}, function(error, doc) {
+      M.findOne({ _id: doc._id }, function(error, doc) {
         assert.ifError(error);
         assert.ok(!doc.ts.createdAt);
         assert.ok(doc.ts.updatedAt);
@@ -218,7 +218,8 @@ describe('timestamps', function() {
     const M = db.model('Test', schema);
 
     const startTime = Date.now();
-    return M.updateOne({}, { name: 'foo' }, { upsert: true }).
+    return M.deleteMany({}).
+      then(() => M.updateOne({}, { name: 'foo' }, { upsert: true })).
       then(() => assert.equal(called, 1)).
       then(() => M.findOne()).
       then(doc => assert.ok(doc.createdAt.valueOf() >= startTime));
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index 535eb087674..da9d47d292a 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -96,11 +96,11 @@ describe('types.buffer', function() {
 
           t.sub.push({ name: 'Friday Friday' });
           t.save(function(err) {
-            assert.ok(err.message.indexOf('UserBuffer validation failed') === 0, err.message);
+            assert.ok(err.message.indexOf('Test validation failed') === 0, err.message);
             assert.equal(err.errors['sub.0.buf'].kind, 'required');
             t.sub[0].buf = Buffer.from('well well');
             t.save(function(err) {
-              assert.ok(err.message.indexOf('UserBuffer validation failed') === 0, err.message);
+              assert.ok(err.message.indexOf('Test validation failed') === 0, err.message);
               assert.equal(err.errors['sub.0.buf'].kind, 'user defined');
               assert.equal(err.errors['sub.0.buf'].message, 'valid failed');
 

From facbe31eff09ff9b16a56061263dab1b737a031b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Mar 2020 10:54:39 -0400
Subject: [PATCH 0626/2348] docs: link to mongoose promise tutorial

---
 test/docs/promises.test.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/docs/promises.test.js b/test/docs/promises.test.js
index 3a96d2ca835..cbea914055e 100644
--- a/test/docs/promises.test.js
+++ b/test/docs/promises.test.js
@@ -30,6 +30,7 @@ describe('promises docs', function () {
    * [async/await](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html).
    * 
    * You can find the return type of specific operations [in the api docs](https://mongoosejs.com/docs/api.html)
+   * You can also read more about [promises in Mongoose](https://masteringjs.io/tutorials/mongoose/promise).
    */
   it('Built-in Promises', function (done) {
     var gnr = new Band({

From a995b5d357f7bf94e1734a067bb1af55f599a0c2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Mar 2020 16:30:46 -0400
Subject: [PATCH 0627/2348] test(document): repro #8689

---
 test/document.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 2edbcf1a8e5..0df52d22aea 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8837,4 +8837,31 @@ describe('document', function() {
     const newDoc = new Model(doc);
     assert.equal(newDoc.name, 'test');
   });
+
+  it('can save nested array after setting (gh-8689)', function() {
+    const schema = new mongoose.Schema({
+      name: String,
+      array: [[{
+        label: String,
+        value: String
+      }]]
+    });
+    const MyModel = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield MyModel.create({ name: 'foo' });
+
+      doc.set({
+        'array.0': [{
+          label: 'hello',
+          value: 'world'
+        }]
+      });
+      yield doc.save();
+
+      const updatedDoc = yield MyModel.findOne({ _id: doc._id });
+      assert.equal(updatedDoc.array[0][0].label, 'hello');
+      assert.equal(updatedDoc.array[0][0].value, 'world');
+    });
+  });
 });

From f650191e76828f4c08920f8918b5c29c859ca45c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Mar 2020 16:30:57 -0400
Subject: [PATCH 0628/2348] fix(document): allow saving document with nested
 document array after setting `nestedArr.0`

Fix #8689
---
 lib/types/core_array.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index c2c08d7703d..a48bc409e4a 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -300,6 +300,10 @@ class CoreMongooseArray extends Array {
         }
       }
 
+      if (dirtyPath != null && dirtyPath.endsWith('.$')) {
+        return this;
+      }
+
       parent.markModified(dirtyPath, arguments.length > 0 ? elem : parent);
     }
 

From 1883bc086d172a8c79252649c46a8b1ac168b13b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Mar 2020 16:38:20 -0400
Subject: [PATCH 0629/2348] chore: release 5.9.6

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index b721ad0592c..1e34cc439f4 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.9.6 / 2020-03-23
+==================
+ * fix(document): allow saving document with nested document array after setting `nestedArr.0` #8689
+ * docs(connections): expand section about multiple connections to describe patterns for exporting schemas #8679
+ * docs(populate): add note about `execPopulate()` to "populate an existing document" section #8671 #8275
+ * docs: fix broken links #8690 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(guide): fix typos #8704 [MateRyze](https://github.com/MateRyze)
+ * docs(guide): fix minor typo #8683 [pkellz](https://github.com/pkellz)
+
 5.9.5 / 2020-03-16
 ==================
  * fix: upgrade mongodb driver -> 3.5.5 #8667 #8664 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 48c5ee8969c..052c13fbb26 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.5",
+  "version": "5.9.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From bfc10f5de6cc0ffad4190b3fd5c45a991c3d9649 Mon Sep 17 00:00:00 2001
From: patrikx3 <alabard@gmail.com>
Date: Thu, 26 Mar 2020 11:24:55 +0100
Subject: [PATCH 0630/2348] Fix: in some Number casts there were an assert
 twice and was not handling undefined.

fixes: https://github.com/Automattic/mongoose/issues/8711
---
 lib/cast/number.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/cast/number.js b/lib/cast/number.js
index 18d2eebe6fd..acb930796cd 100644
--- a/lib/cast/number.js
+++ b/lib/cast/number.js
@@ -14,9 +14,8 @@ const assert = require('assert');
  */
 
 module.exports = function castNumber(val) {
-  assert.ok(!isNaN(val));
 
-  if (val == null) {
+  if (val == null || val === undefined) {
     return val;
   }
   if (val === '') {

From 6c66b06058567d271666865bf662c58d7b629136 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Mar 2020 14:03:39 -0400
Subject: [PATCH 0631/2348] chore: add new opencollective sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index a2cf38f702e..9e3110e8335 100644
--- a/index.pug
+++ b/index.pug
@@ -298,6 +298,9 @@ html(lang='en')
               <a href="https://www.coinnewsspan.com/">
                 <img class="sponsor" src="https://images.opencollective.com/coinnewsspan/c0933b4/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://mobilunity.com/">
+                <img class="sponsor" src="https://images.opencollective.com/mobilunity/e4ca372/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 023023359c13db7a24821e346268a4930a149e4d Mon Sep 17 00:00:00 2001
From: patrikx3 <alabard@gmail.com>
Date: Fri, 27 Mar 2020 20:14:19 +0100
Subject: [PATCH 0632/2348] Update number.js

---
 lib/cast/number.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/cast/number.js b/lib/cast/number.js
index acb930796cd..68053d998c2 100644
--- a/lib/cast/number.js
+++ b/lib/cast/number.js
@@ -15,7 +15,7 @@ const assert = require('assert');
 
 module.exports = function castNumber(val) {
 
-  if (val == null || val === undefined) {
+  if (val == null) {
     return val;
   }
   if (val === '') {

From 7c2d74e98dd7311208a4802947aa7d2e81815b52 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Mar 2020 16:05:35 -0400
Subject: [PATCH 0633/2348] fix(model): allow bulkWrite upsert with empty
 `update`

Re: #8698
---
 lib/helpers/model/castBulkWrite.js |  1 +
 lib/helpers/query/castUpdate.js    | 17 ++---------------
 lib/query.js                       |  2 +-
 test/model.test.js                 | 22 ++++++++++++++++++++++
 test/query.test.js                 |  8 --------
 5 files changed, 26 insertions(+), 24 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 1d8e51b6353..27821994977 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -44,6 +44,7 @@ module.exports = function castBulkWrite(model, op, options) {
           strict: model.schema.options.strict,
           overwrite: false
         });
+
         if (op['updateOne'].setDefaultsOnInsert) {
           setDefaultsOnInsert(op['updateOne']['filter'], model.schema, op['updateOne']['update'], {
             setDefaultsOnInsert: true,
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index bdad8044558..b45f6d1863c 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -45,7 +45,6 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
   const ops = Object.keys(obj);
   let i = ops.length;
   const ret = {};
-  let hasKeys;
   let val;
   let hasDollarKey = false;
   const overwrite = options.overwrite;
@@ -81,12 +80,6 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
   // cast each value
   i = ops.length;
 
-  // if we get passed {} for the update, we still need to respect that when it
-  // is an overwrite scenario
-  if (overwrite) {
-    hasKeys = true;
-  }
-
   while (i--) {
     const op = ops[i];
     val = ret[op];
@@ -96,14 +89,8 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
         typeof val === 'object' &&
         !Buffer.isBuffer(val) &&
         (!overwrite || hasDollarKey)) {
-      hasKeys |= walkUpdatePath(schema, val, op, options, context, filter);
+      walkUpdatePath(schema, val, op, options, context, filter);
     } else if (overwrite && ret && typeof ret === 'object') {
-      // if we are just using overwrite, cast the query and then we will
-      // *always* return the value, even if it is an empty object. We need to
-      // set hasKeys above because we need to account for the case where the
-      // user passes {} and wants to clobber the whole document
-      // Also, _walkUpdatePath expects an operation, so give it $set since that
-      // is basically what we're doing
       walkUpdatePath(schema, ret, '$set', options, context, filter);
     } else {
       const msg = 'Invalid atomic update value for ' + op + '. '
@@ -116,7 +103,7 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
     }
   }
 
-  return hasKeys && ret;
+  return ret;
 };
 
 /*!
diff --git a/lib/query.js b/lib/query.js
index 681093e3cc7..9c31241e933 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3472,7 +3472,7 @@ Query.prototype._findAndModify = function(type, callback) {
     if (!isOverwriting) {
       this._update = castDoc(this, opts.overwrite);
       this._update = setDefaultsOnInsert(this._conditions, schema, this._update, opts);
-      if (!this._update) {
+      if (!this._update || Object.keys(this._update).length === 0) {
         if (opts.upsert) {
           // still need to do the upsert to empty doc
           const doc = utils.clone(castedQuery);
diff --git a/test/model.test.js b/test/model.test.js
index 0052d31f4ef..e6eff19c07b 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6474,4 +6474,26 @@ describe('Model', function() {
       assert.strictEqual(res.breed, 'Chorkie');
     });
   });
+
+  it('bulkWrite upsert works when update casts to empty (gh-8698)', function() {
+    const userSchema = new Schema({
+      name: String
+    });
+    const User = db.model('User', userSchema);
+    mongoose.set('debug', true)
+
+    return co(function*() {
+      yield User.bulkWrite([{
+        updateOne: {
+          filter: { name: 'test' },
+          update: { notInSchema: true },
+          upsert: true
+        }
+      }]);
+
+      const doc = yield User.findOne();
+      assert.ok(doc);
+      assert.strictEqual(doc.notInSchema, null);
+    });
+  });
 });
diff --git a/test/query.test.js b/test/query.test.js
index b3706609fd8..589f138d41c 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1645,14 +1645,6 @@ describe('Query', function() {
     assert.strictEqual(opts.maxTimeMS, 1000);
   });
 
-  describe('update', function() {
-    it('when empty, nothing is run', function(done) {
-      const q = new Query;
-      assert.equal(false, !!q._castUpdate({}));
-      done();
-    });
-  });
-
   describe('bug fixes', function() {
     describe('collations', function() {
       before(function(done) {

From 757af84fbbff5b050c75ad702773ade0c0870e72 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Mar 2020 16:54:19 -0400
Subject: [PATCH 0634/2348] test: repro #8698

---
 test/model.test.js | 46 ++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 44 insertions(+), 2 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index e6eff19c07b..1c49017d794 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6480,7 +6480,6 @@ describe('Model', function() {
       name: String
     });
     const User = db.model('User', userSchema);
-    mongoose.set('debug', true)
 
     return co(function*() {
       yield User.bulkWrite([{
@@ -6493,7 +6492,50 @@ describe('Model', function() {
 
       const doc = yield User.findOne();
       assert.ok(doc);
-      assert.strictEqual(doc.notInSchema, null);
+      assert.strictEqual(doc.notInSchema, undefined);
+    });
+  });
+
+  it('bulkWrite upsert with non-schema path in filter (gh-8698)', function() {
+    const userSchema = new Schema({
+      name: String
+    });
+    const User = db.model('User', userSchema);
+    mongoose.set('debug', true)
+
+    return co(function*() {
+      let err = yield User.bulkWrite([{
+        updateOne: {
+          filter: { notInSchema: 'foo' },
+          update: { name: 'test' },
+          upsert: true
+        }
+      }]).then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.name, 'StrictModeError');
+      assert.ok(err.message.indexOf('notInSchema') !== -1, err.message);
+
+      err = yield User.bulkWrite([{
+        updateMany: {
+          filter: { notInSchema: 'foo' },
+          update: { name: 'test' },
+          upsert: true
+        }
+      }]).then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.name, 'StrictModeError');
+      assert.ok(err.message.indexOf('notInSchema') !== -1, err.message);
+
+      err = yield User.bulkWrite([{
+        replaceOne: {
+          filter: { notInSchema: 'foo' },
+          update: { name: 'test' },
+          upsert: true
+        }
+      }]).then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.name, 'StrictModeError');
+      assert.ok(err.message.indexOf('notInSchema') !== -1, err.message);
     });
   });
 });

From 713b601b7e9f75200a16606ce9a6e7d4cdbd4774 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Mar 2020 16:54:40 -0400
Subject: [PATCH 0635/2348] fix(model): make bulkWrite updates error if
 `strict` and `upsert` are set and `filter` contains a non-schema path

Fix #8698
---
 lib/helpers/model/castBulkWrite.js | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 27821994977..21e679e735f 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -39,7 +39,10 @@ module.exports = function castBulkWrite(model, op, options) {
         if (!op['updateOne']['update']) throw new Error('Must provide an update object.');
 
         _addDiscriminatorToObject(schema, op['updateOne']['filter']);
-        op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter']);
+        op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter'], {
+          strict: model.schema.options.strict,
+          upsert: op['updateOne'].upsert
+        });
         op['updateOne']['update'] = castUpdate(model.schema, op['updateOne']['update'], {
           strict: model.schema.options.strict,
           overwrite: false
@@ -70,7 +73,10 @@ module.exports = function castBulkWrite(model, op, options) {
         if (!op['updateMany']['update']) throw new Error('Must provide an update object.');
 
         _addDiscriminatorToObject(schema, op['updateMany']['filter']);
-        op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter']);
+        op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter'], {
+          strict: model.schema.options.strict,
+          upsert: op['updateMany'].upsert
+        });
         op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
           strict: model.schema.options.strict,
           overwrite: false
@@ -97,8 +103,10 @@ module.exports = function castBulkWrite(model, op, options) {
     return (callback) => {
       _addDiscriminatorToObject(schema, op['replaceOne']['filter']);
       try {
-        op['replaceOne']['filter'] = cast(model.schema,
-          op['replaceOne']['filter']);
+        op['replaceOne']['filter'] = cast(model.schema, op['replaceOne']['filter'], {
+          strict: model.schema.options.strict,
+          upsert: op['replaceOne'].upsert
+        });
       } catch (error) {
         return callback(error, null);
       }

From 52eb75d2d46e0adfb69590f4d1a9f0dc05c20f2d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Mar 2020 16:57:20 -0400
Subject: [PATCH 0636/2348] style: fix lint

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 1c49017d794..91852bdc83d 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6501,7 +6501,7 @@ describe('Model', function() {
       name: String
     });
     const User = db.model('User', userSchema);
-    mongoose.set('debug', true)
+    mongoose.set('debug', true);
 
     return co(function*() {
       let err = yield User.bulkWrite([{

From 91560dcf62184c27fcdc5b340cd0348649f333f3 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 27 Mar 2020 23:50:31 +0200
Subject: [PATCH 0637/2348] Remove mongoose.set('debug', true); from test

---
 test/model.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 91852bdc83d..3ad99263c24 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6501,7 +6501,6 @@ describe('Model', function() {
       name: String
     });
     const User = db.model('User', userSchema);
-    mongoose.set('debug', true);
 
     return co(function*() {
       let err = yield User.bulkWrite([{

From ee135ef90ec7afd48e12d83fbce9a137112fdac8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Mar 2020 12:49:43 -0400
Subject: [PATCH 0638/2348] fix(query): ensure stack trace shows `exec()` when
 casting conditions with `findOne()`

Re: #8691
---
 lib/error/cast.js | 48 ++++++++++++++++++++++++++++++++++++-----------
 lib/query.js      | 22 +++++++++++++++++++---
 2 files changed, 56 insertions(+), 14 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 87f1ce9327d..1e9ffaf9dab 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -18,6 +18,32 @@ const util = require('util');
  */
 
 function CastError(type, value, path, reason, schemaType) {
+  // If no args, assume we'll `init()` later.
+  if (arguments.length > 0) {
+    this.init(type, value, path, reason, schemaType);
+  }
+
+  MongooseError.call(this, this.formatMessage());
+  this.name = 'CastError';
+  if (Error.captureStackTrace) {
+    Error.captureStackTrace(this);
+  } else {
+    this.stack = new Error().stack;
+  }
+}
+
+/*!
+ * Inherits from MongooseError.
+ */
+
+CastError.prototype = Object.create(MongooseError.prototype);
+CastError.prototype.constructor = MongooseError;
+
+/*!
+ * ignore
+ */
+
+CastError.prototype.init = function init(type, value, path, reason, schemaType) {
   let stringValue = util.inspect(value);
   stringValue = stringValue.replace(/^'/, '"').replace(/'$/, '"');
   if (!stringValue.startsWith('"')) {
@@ -33,21 +59,21 @@ function CastError(type, value, path, reason, schemaType) {
   this.value = value;
   this.path = path;
   this.reason = reason;
-  MongooseError.call(this, this.formatMessage());
-  this.name = 'CastError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
-  }
-}
+};
 
 /*!
- * Inherits from MongooseError.
+ * ignore
  */
 
-CastError.prototype = Object.create(MongooseError.prototype);
-CastError.prototype.constructor = MongooseError;
+CastError.prototype.copy = function copy(other) {
+  this.messageFormat = other.messageFormat;
+  this.stringValue = other.stringValue;
+  this.kind = other.type;
+  this.value = other.value;
+  this.path = other.path;
+  this.reason = other.reason;
+  this.message = other.message;
+};
 
 /*!
  * ignore
diff --git a/lib/query.js b/lib/query.js
index 9c31241e933..c4a2723dcba 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4331,6 +4331,9 @@ function _orFailError(err, query) {
 
 Query.prototype.exec = function exec(op, callback) {
   const _this = this;
+  // Ensure that `exec()` is the first thing that shows up in
+  // the stack when cast errors happen.
+  const castError = new CastError();
 
   if (typeof op === 'function') {
     callback = op;
@@ -4351,16 +4354,16 @@ Query.prototype.exec = function exec(op, callback) {
 
     this._hooks.execPre('exec', this, [], (error) => {
       if (error != null) {
-        return cb(error);
+        return cb(_cleanCastErrorStack(castError, error));
       }
       this[this.op].call(this, (error, res) => {
         if (error) {
-          return cb(error);
+          return cb(_cleanCastErrorStack(castError, error));
         }
 
         this._hooks.execPost('exec', this, [], {}, (error) => {
           if (error) {
-            return cb(error);
+            return cb(_cleanCastErrorStack(castError, error));
           }
 
           cb(null, res);
@@ -4370,6 +4373,19 @@ Query.prototype.exec = function exec(op, callback) {
   }, this.model.events);
 };
 
+/*!
+ * ignore
+ */
+
+function _cleanCastErrorStack(castError, error) {
+  if (error instanceof CastError) {
+    castError.copy(error);
+    return castError;
+  }
+
+  return error;
+}
+
 /*!
  * ignore
  */

From 055b75da23d1a92bb31de19679f4f8c0001cd078 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Mar 2020 13:31:06 -0400
Subject: [PATCH 0639/2348] refactor(query): always call `exec()` when
 executing a query instead of calling query thunks directly

Re: #8691
---
 lib/query.js              | 68 +++++++++++++++++++--------------------
 test/query.cursor.test.js |  1 +
 2 files changed, 35 insertions(+), 34 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 9c31241e933..85eaf941603 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1968,6 +1968,8 @@ Query.prototype._find = wrapThunk(function(callback) {
  */
 
 Query.prototype.find = function(conditions, callback) {
+  this.op = 'find';
+
   if (typeof conditions === 'function') {
     callback = conditions;
     conditions = {};
@@ -1988,7 +1990,7 @@ Query.prototype.find = function(conditions, callback) {
     return Query.base.find.call(this);
   }
 
-  this._find(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -2212,7 +2214,7 @@ Query.prototype.findOne = function(conditions, projection, options, callback) {
     return Query.base.findOne.call(this);
   }
 
-  this._findOne(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -2320,6 +2322,7 @@ Query.prototype._estimatedDocumentCount = wrapThunk(function(callback) {
  */
 
 Query.prototype.count = function(filter, callback) {
+  this.op = 'count';
   if (typeof filter === 'function') {
     callback = filter;
     filter = undefined;
@@ -2331,12 +2334,11 @@ Query.prototype.count = function(filter, callback) {
     this.merge(filter);
   }
 
-  this.op = 'count';
   if (!callback) {
     return this;
   }
 
-  this._count(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -2366,6 +2368,7 @@ Query.prototype.count = function(filter, callback) {
  */
 
 Query.prototype.estimatedDocumentCount = function(options, callback) {
+  this.op = 'estimatedDocumentCount';
   if (typeof options === 'function') {
     callback = options;
     options = undefined;
@@ -2375,12 +2378,11 @@ Query.prototype.estimatedDocumentCount = function(options, callback) {
     this.setOptions(options);
   }
 
-  this.op = 'estimatedDocumentCount';
   if (!callback) {
     return this;
   }
 
-  this._estimatedDocumentCount(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -2429,6 +2431,7 @@ Query.prototype.estimatedDocumentCount = function(options, callback) {
  */
 
 Query.prototype.countDocuments = function(conditions, callback) {
+  this.op = 'countDocuments';
   if (typeof conditions === 'function') {
     callback = conditions;
     conditions = undefined;
@@ -2440,12 +2443,11 @@ Query.prototype.countDocuments = function(conditions, callback) {
     this.merge(conditions);
   }
 
-  this.op = 'countDocuments';
   if (!callback) {
     return this;
   }
 
-  this._countDocuments(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -2523,7 +2525,7 @@ Query.prototype.distinct = function(field, conditions, callback) {
   this.op = 'distinct';
 
   if (callback != null) {
-    this.__distinct(callback);
+    this.exec(callback);
   }
 
   return this;
@@ -2634,7 +2636,7 @@ Query.prototype.remove = function(filter, callback) {
     return Query.base.remove.call(this);
   }
 
-  this._remove(callback);
+  this.exec(callback);
   return this;
 };
 
@@ -2691,6 +2693,7 @@ Query.prototype._remove = wrapThunk(function(callback) {
  */
 
 Query.prototype.deleteOne = function(filter, options, callback) {
+  this.op = 'deleteOne';
   if (typeof filter === 'function') {
     callback = filter;
     filter = null;
@@ -2716,7 +2719,7 @@ Query.prototype.deleteOne = function(filter, options, callback) {
     return Query.base.deleteOne.call(this);
   }
 
-  this._deleteOne.call(this, callback);
+  this.exec.call(this, callback);
 
   return this;
 };
@@ -2774,6 +2777,7 @@ Query.prototype._deleteOne = wrapThunk(function(callback) {
  */
 
 Query.prototype.deleteMany = function(filter, options, callback) {
+  this.op = 'deleteMany';
   if (typeof filter === 'function') {
     callback = filter;
     filter = null;
@@ -2799,7 +2803,7 @@ Query.prototype.deleteMany = function(filter, options, callback) {
     return Query.base.deleteMany.call(this);
   }
 
-  this._deleteMany.call(this, callback);
+  this.exec.call(this, callback);
 
   return this;
 };
@@ -3003,7 +3007,7 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
     return this;
   }
 
-  this._findOneAndUpdate(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -3098,7 +3102,7 @@ Query.prototype.findOneAndRemove = function(conditions, options, callback) {
     return this;
   }
 
-  this._findOneAndRemove(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -3183,7 +3187,7 @@ Query.prototype.findOneAndDelete = function(conditions, options, callback) {
     return this;
   }
 
-  this._findOneAndDelete(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -3317,7 +3321,7 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
     return this;
   }
 
-  this._findOneAndReplace(callback);
+  this.exec(callback);
 
   return this;
 };
@@ -3690,6 +3694,10 @@ function _updateThunk(op, callback) {
   }
 
   callback = _wrapThunkCallback(this, callback);
+  const oldCb = callback;
+  callback = function(error, result) {
+    oldCb(error, result ? result.result : { ok: 0, n: 0, nModified: 0 });
+  };
 
   const castedQuery = this._conditions;
   const options = this._optionsForExec(this.model);
@@ -4149,17 +4157,6 @@ function _update(query, op, filter, doc, options, callback) {
   filter = utils.toObject(filter);
   doc = doc || {};
 
-  const oldCb = callback;
-  if (oldCb) {
-    if (typeof oldCb === 'function') {
-      callback = function(error, result) {
-        oldCb(error, result ? result.result : { ok: 0, n: 0, nModified: 0 });
-      };
-    } else {
-      throw new Error('Invalid callback() argument.');
-    }
-  }
-
   // strict is an option used in the update checking, make sure it gets set
   if (options != null) {
     if ('strict' in options) {
@@ -4183,11 +4180,8 @@ function _update(query, op, filter, doc, options, callback) {
 
   // Hooks
   if (callback) {
-    if (op === 'update') {
-      query._execUpdate(callback);
-      return query;
-    }
-    query['_' + op](callback);
+    query.exec(callback);
+
     return query;
   }
 
@@ -4265,7 +4259,7 @@ Query.prototype.orFail = function(err) {
       case 'update':
       case 'updateMany':
       case 'updateOne':
-        if (get(res, 'result.nModified') === 0) {
+        if (get(res, 'nModified') === 0) {
           throw _orFailError(err, this);
         }
         break;
@@ -4353,7 +4347,13 @@ Query.prototype.exec = function exec(op, callback) {
       if (error != null) {
         return cb(error);
       }
-      this[this.op].call(this, (error, res) => {
+      let thunk = '_' + this.op;
+      if (this.op === 'update') {
+        thunk = '_execUpdate';
+      } else if (this.op === 'distinct') {
+        thunk = '__distinct';
+      }
+      this[thunk].call(this, (error, res) => {
         if (error) {
           return cb(error);
         }
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 9bde285ebab..af474c30754 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -494,6 +494,7 @@ describe('QueryCursor', function() {
     const Movie = db.model('Movie', schema);
 
     return co(function*() {
+      yield Movie.deleteMany({});
       yield Movie.create([
         { name: 'Kickboxer' },
         { name: 'Ip Man' },

From c41c63844ff017997f9f9e16f70205221af6b56f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Mar 2020 15:56:41 -0400
Subject: [PATCH 0640/2348] test: fix tests re: #8691

---
 lib/query.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/query.js b/lib/query.js
index 85eaf941603..a42e8ceb422 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2617,6 +2617,7 @@ Query.prototype.sort = function(arg) {
  */
 
 Query.prototype.remove = function(filter, callback) {
+  this.op = 'remove';
   if (typeof filter === 'function') {
     callback = filter;
     filter = null;

From 486c0201e89ecf1642e96df051b1e8c09ec55abb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Mar 2020 16:21:33 -0400
Subject: [PATCH 0641/2348] test: fix tests re: #8725

---
 lib/cast/number.js        |  1 -
 lib/query.js              |  6 +++---
 lib/schema/array.js       |  6 ++++++
 test/types.array.test.js  |  2 +-
 test/types.number.test.js | 12 ------------
 5 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/lib/cast/number.js b/lib/cast/number.js
index 68053d998c2..7cd7f848c53 100644
--- a/lib/cast/number.js
+++ b/lib/cast/number.js
@@ -14,7 +14,6 @@ const assert = require('assert');
  */
 
 module.exports = function castNumber(val) {
-
   if (val == null) {
     return val;
   }
diff --git a/lib/query.js b/lib/query.js
index a42e8ceb422..8496f35d2b2 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2174,6 +2174,8 @@ Query.prototype._findOne = wrapThunk(function(callback) {
  */
 
 Query.prototype.findOne = function(conditions, projection, options, callback) {
+  this.op = 'findOne';
+
   if (typeof conditions === 'function') {
     callback = conditions;
     conditions = null;
@@ -2191,8 +2193,6 @@ Query.prototype.findOne = function(conditions, projection, options, callback) {
   // make sure we don't send in the whole Document to merge()
   conditions = utils.toObject(conditions);
 
-  this.op = 'findOne';
-
   if (options) {
     this.setOptions(options);
   }
@@ -2498,6 +2498,7 @@ Query.prototype.__distinct = wrapThunk(function __distinct(callback) {
  */
 
 Query.prototype.distinct = function(field, conditions, callback) {
+  this.op = 'distinct';
   if (!callback) {
     if (typeof conditions === 'function') {
       callback = conditions;
@@ -2522,7 +2523,6 @@ Query.prototype.distinct = function(field, conditions, callback) {
   if (field != null) {
     this._distinct = field;
   }
-  this.op = 'distinct';
 
   if (callback != null) {
     this.exec(callback);
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 86589f122b9..7831d0bf67f 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -349,6 +349,12 @@ SchemaArray.prototype.cast = function(value, doc, init) {
     if (this.caster && this.casterConstructor !== Mixed) {
       try {
         for (i = 0, l = value.length; i < l; i++) {
+          // Special case: number arrays disallow undefined.
+          // Re: gh-840
+          // See commit 1298fe92d2c790a90594bd08199e45a4a09162a6
+          if (this.caster.instance === 'Number' && value[i] === void 0) {
+            throw new MongooseError('Mongoose number arrays disallow storing undefined');
+          }
           value[i] = this.caster.cast(value[i], doc, init);
         }
       } catch (e) {
diff --git a/test/types.array.test.js b/test/types.array.test.js
index a3c4316bc45..902dd2b0651 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -1769,7 +1769,7 @@ describe('types array', function() {
 
   describe('of number', function() {
     it('allows nulls', function(done) {
-      const schema = new Schema({ x: [Number] }, { collection: 'nullsareallowed' + random() });
+      const schema = new Schema({ x: [Number] });
       const M = db.model('Test', schema);
       let m;
 
diff --git a/test/types.number.test.js b/test/types.number.test.js
index fa8b152f6e6..27b3114f89f 100644
--- a/test/types.number.test.js
+++ b/test/types.number.test.js
@@ -27,18 +27,6 @@ describe('types.number', function() {
     done();
   });
 
-  it('undefined throws number cast error', function(done) {
-    const n = new SchemaNumber();
-    let err;
-    try {
-      n.cast(undefined);
-    } catch (e) {
-      err = e;
-    }
-    assert.strictEqual(true, !!err);
-    done();
-  });
-
   it('array throws cast number error', function(done) {
     const n = new SchemaNumber();
     let err;

From 088633fa2a51b2dc783c4779bf2451d09c35453e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Mar 2020 16:24:58 -0400
Subject: [PATCH 0642/2348] style: fix lint

---
 test/types.array.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/types.array.test.js b/test/types.array.test.js
index 902dd2b0651..ff8bcb0e69f 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -11,7 +11,6 @@ const assert = require('assert');
 const co = require('co');
 const mongodb = require('mongodb');
 const mongoose = require('./common').mongoose;
-const random = require('../lib/utils').random;
 
 const MongooseArray = mongoose.Types.Array;
 const Schema = mongoose.Schema;

From 074c6f594d7ea55382a002f71bc0deaa93d5fe56 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Mar 2020 12:56:08 -0400
Subject: [PATCH 0643/2348] fix(query): clean stack trace for filter cast
 errors so they include the calling file

Fix #8691
---
 test/query.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index 589f138d41c..4f974363580 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3598,4 +3598,19 @@ describe('Query', function() {
       assert.ok(res);
     });
   });
+
+  describe('stack traces', function() {
+    it('includes calling file for filter cast errors (gh-8691)', function() {
+      const toCheck = ['find', 'findOne', 'deleteOne'];
+      const Model = db.model('Test', Schema({}));
+
+      return co(function*() {
+        for (const fn of toCheck) {
+          const err = yield Model[fn]({ _id: 'fail' }).then(() => null, err => err);
+          assert.ok(err);
+          assert.ok(err.stack.includes(__filename), err.stack);
+        }
+      });
+    });
+  });
 });

From 4cbabb6bf5ba3bed7633f0171b6f436f7a126eb0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Mar 2020 13:51:40 -0400
Subject: [PATCH 0644/2348] fix(map): avoid infinite loop when setting a map of
 documents to a document copied using spread operator

Fix #8722
---
 lib/document.js                         |  5 ++---
 lib/helpers/document/handleSpreadDoc.js | 17 ++++++++++++++++
 lib/types/map.js                        |  2 ++
 test/types.map.test.js                  | 27 +++++++++++++++++++++++++
 4 files changed, 48 insertions(+), 3 deletions(-)
 create mode 100644 lib/helpers/document/handleSpreadDoc.js

diff --git a/lib/document.js b/lib/document.js
index b81e45b1c71..aaa62ff530c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -23,6 +23,7 @@ const defineKey = require('./helpers/document/compile').defineKey;
 const flatten = require('./helpers/common').flatten;
 const get = require('./helpers/get');
 const getEmbeddedDiscriminatorPath = require('./helpers/document/getEmbeddedDiscriminatorPath');
+const handleSpreadDoc = require('./helpers/document/handleSpreadDoc');
 const idGetter = require('./plugins/idGetter');
 const isDefiningProjection = require('./helpers/projection/isDefiningProjection');
 const isExclusive = require('./helpers/projection/isExclusive');
@@ -991,9 +992,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
   // Assume this is a Mongoose document that was copied into a POJO using
   // `Object.assign()` or `{...doc}`
-  if (utils.isPOJO(val) && val.$__ != null && val._doc != null) {
-    val = val._doc;
-  }
+  val = handleSpreadDoc(val);
 
   if (pathType === 'nested' && val) {
     if (typeof val === 'object' && val != null) {
diff --git a/lib/helpers/document/handleSpreadDoc.js b/lib/helpers/document/handleSpreadDoc.js
new file mode 100644
index 00000000000..d3075e41365
--- /dev/null
+++ b/lib/helpers/document/handleSpreadDoc.js
@@ -0,0 +1,17 @@
+'use strict';
+
+const utils = require('../../utils');
+
+/**
+ * Using spread operator on a Mongoose document gives you a
+ * POJO that has a tendency to cause infinite recursion. So
+ * we use this function on `set()` to prevent that.
+ */
+
+module.exports = function handleSpreadDoc(v) {
+  if (utils.isPOJO(v) && v.$__ != null && v._doc != null) {
+    return v._doc;
+  }
+
+  return v;
+};
\ No newline at end of file
diff --git a/lib/types/map.js b/lib/types/map.js
index dae044d1a97..df32be82137 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -3,6 +3,7 @@
 const Mixed = require('../schema/mixed');
 const deepEqual = require('../utils').deepEqual;
 const get = require('../helpers/get');
+const handleSpreadDoc = require('../helpers/document/handleSpreadDoc');
 const util = require('util');
 const specialProperties = require('../helpers/specialProperties');
 
@@ -42,6 +43,7 @@ class MongooseMap extends Map {
 
   set(key, value) {
     checkValidKey(key);
+    value = handleSpreadDoc(value);
 
     // Weird, but because you can't assign to `this` before calling `super()`
     // you can't get access to `$__schemaType` to cast in the initial call to
diff --git a/test/types.map.test.js b/test/types.map.test.js
index c5c1b5546a9..666eab716ba 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -817,4 +817,31 @@ describe('Map', function() {
       assert.deepEqual(doc.modifiedPaths(), []);
     });
   });
+
+  it('handles setting map value to spread document (gh-8652)', function() {
+    const childSchema = mongoose.Schema({ name: String }, { _id: false });
+    const schema = mongoose.Schema({
+      docMap: {
+        type: Map,
+        of: childSchema
+      }
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      yield Model.create({
+        docMap: {
+          captain: { name: 'Jean-Luc Picard' },
+          firstOfficer: { name: 'Will Riker' }
+        }
+      });
+      const doc = yield Model.findOne();
+
+      doc.docMap.set('captain', Object.assign({}, doc.docMap.get('firstOfficer')));
+      yield doc.save();
+
+      const fromDb = yield Model.findOne();
+      assert.equal(fromDb.docMap.get('firstOfficer').name, 'Will Riker');
+    });
+  });
 });

From 4015625b33affd7e277cf0ff752cedf729fef41b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Mar 2020 12:16:13 -0400
Subject: [PATCH 0645/2348] chore: release 5.9.7

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 1e34cc439f4..1c67ef0a43e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.9.7 / 2020-03-30
+==================
+ * fix(map): avoid infinite loop when setting a map of documents to a document copied using spread operator #8722
+ * fix(query): clean stack trace for filter cast errors so they include the calling file #8691
+ * fix(model): make bulkWrite updates error if `strict` and `upsert` are set and `filter` contains a non-schema path #8698
+ * fix(cast): make internal `castToNumber()` allow undefined #8725 [p3x-robot](https://github.com/p3x-robot)
+
 5.9.6 / 2020-03-23
 ==================
  * fix(document): allow saving document with nested document array after setting `nestedArr.0` #8689
diff --git a/package.json b/package.json
index 052c13fbb26..10fa330fa0d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.6",
+  "version": "5.9.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a0f7330f682c4247fd476cee212ac748f0b2dfda Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 31 Mar 2020 15:32:13 -0400
Subject: [PATCH 0646/2348] chore: add opencollective sponsor

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 9e3110e8335..55035f4d1fc 100644
--- a/index.pug
+++ b/index.pug
@@ -301,6 +301,9 @@ html(lang='en')
               <a href="https://mobilunity.com/">
                 <img class="sponsor" src="https://images.opencollective.com/mobilunity/e4ca372/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.paraskasino.fi/">
+                <img class="sponsor" src="https://images.opencollective.com/paraskasino/a39c3d6/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 8b4437d63ce28323f7ebb5dd078719c1b455d9f5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Apr 2020 10:16:35 -0400
Subject: [PATCH 0647/2348] chore: update opencollective sponsors

---
 index.pug | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/index.pug b/index.pug
index 55035f4d1fc..a5d4b17b065 100644
--- a/index.pug
+++ b/index.pug
@@ -265,9 +265,6 @@ html(lang='en')
               <a href="https://www.bonus.com.de/freispiele">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-deutschland/646169e/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.crosswordsolver.com/">
-                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/crosswordsolver.png" style="height: 80px">
-              </a>
               <a href="https://www.monetta.pl/">
                 <img class="sponsor" src="https://images.opencollective.com/monetta/7d65ae6/logo.png" style="height: 100px">
               </a>

From 0594642c0d157d00e74d2e57b15a24551f5035ee Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Apr 2020 16:16:21 -0400
Subject: [PATCH 0648/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index a5d4b17b065..76b97798685 100644
--- a/index.pug
+++ b/index.pug
@@ -301,6 +301,9 @@ html(lang='en')
               <a href="https://www.paraskasino.fi/">
                 <img class="sponsor" src="https://images.opencollective.com/paraskasino/a39c3d6/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://casinoonline.casino/">
+                <img class="sponsor" src="https://images.opencollective.com/casino-online/4c8371c/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 8a71ea9074222af4877e4fc1ba6aa76ec17810c6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Apr 2020 03:21:40 +0200
Subject: [PATCH 0649/2348] allow setting timestamps to false for bulkWrite

---
 lib/helpers/model/castBulkWrite.js |  4 ++--
 lib/model.js                       |  2 ++
 test/model.test.js                 | 25 +++++++++++++++++++++++++
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 21e679e735f..15b7e5dff4c 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -54,7 +54,7 @@ module.exports = function castBulkWrite(model, op, options) {
             upsert: op['updateOne'].upsert
           });
         }
-        if (model.schema.$timestamps != null) {
+        if (model.schema.$timestamps != null && op['updateOne'].timestamps !== false) {
           const createdAt = model.schema.$timestamps.createdAt;
           const updatedAt = model.schema.$timestamps.updatedAt;
           applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateOne']['update'], {});
@@ -87,7 +87,7 @@ module.exports = function castBulkWrite(model, op, options) {
             upsert: op['updateMany'].upsert
           });
         }
-        if (model.schema.$timestamps != null) {
+        if (model.schema.$timestamps != null && op['updateMany'].timestamps !== false) {
           const createdAt = model.schema.$timestamps.createdAt;
           const updatedAt = model.schema.$timestamps.updatedAt;
           applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateMany']['update'], {});
diff --git a/lib/model.js b/lib/model.js
index 13ad9e5f871..5bfa3b9c363 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3451,11 +3451,13 @@ function _setIsNew(doc, val) {
  * @param {Object} [opts.updateOne.filter] Update the first document that matches this filter
  * @param {Object} [opts.updateOne.update] An object containing [update operators](https://docs.mongodb.com/manual/reference/operator/update/)
  * @param {Boolean} [opts.updateOne.upsert=false] If true, insert a doc if none match
+ * @param {Boolean} [opts.updateOne.timestamps=true] If false, do not apply [timestamps](https://mongoosejs.com/docs/guide.html#timestamps) to the operation
  * @param {Object} [opts.updateOne.collation] The [MongoDB collation](https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations) to use
  * @param {Array} [opts.updateOne.arrayFilters] The [array filters](https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-array-filters.html) used in `update`
  * @param {Object} [opts.updateMany.filter] Update all the documents that match this filter
  * @param {Object} [opts.updateMany.update] An object containing [update operators](https://docs.mongodb.com/manual/reference/operator/update/)
  * @param {Boolean} [opts.updateMany.upsert=false] If true, insert a doc if no documents match `filter`
+ * @param {Boolean} [opts.updateMany.timestamps=true] If false, do not apply [timestamps](https://mongoosejs.com/docs/guide.html#timestamps) to the operation
  * @param {Object} [opts.updateMany.collation] The [MongoDB collation](https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations) to use
  * @param {Array} [opts.updateMany.arrayFilters] The [array filters](https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-array-filters.html) used in `update`
  * @param {Object} [opts.deleteOne.filter] Delete the first document that matches this filter
diff --git a/test/model.test.js b/test/model.test.js
index 3ad99263c24..7eddda9e375 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6537,4 +6537,29 @@ describe('Model', function() {
       assert.ok(err.message.indexOf('notInSchema') !== -1, err.message);
     });
   });
+
+  it('bulkWrite can disable timestamps with updateOne, and updateMany', function() {
+    const userSchema = new Schema({
+      name: String
+    }, { timestamps: true });
+
+    const User = db.model('User', userSchema);
+
+    return co(function*() {
+      const [user1, user2] = yield User.create([{ name: 'Hafez1' }, { name: 'Hafez2' }]);
+
+      yield User.bulkWrite([
+        { updateOne: { filter: { _id: user1._id }, update: { name: 'John1' }, timestamps: false } },
+        { updateMany: { filter: { _id: user2._id }, update: { name: 'John2' }, timestamps: false } }
+      ]);
+
+      const [updatedUser1, updatedUser2] = yield Promise.all([
+        User.findOne({ _id: user1._id }),
+        User.findOne({ _id: user2._id })
+      ]);
+
+      assert.deepEqual(user1.updatedAt, updatedUser1.updatedAt);
+      assert.deepEqual(user2.updatedAt, updatedUser2.updatedAt);
+    });
+  });
 });

From 4df21d507fdb09f90dc1a89fb805a19b9da7cf01 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Apr 2020 03:51:17 +0200
Subject: [PATCH 0650/2348] Use array index instead of destructuring for test

---
 test/model.test.js | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 7eddda9e375..7e2e573adc9 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6546,20 +6546,20 @@ describe('Model', function() {
     const User = db.model('User', userSchema);
 
     return co(function*() {
-      const [user1, user2] = yield User.create([{ name: 'Hafez1' }, { name: 'Hafez2' }]);
+      const users = yield User.create([{ name: 'Hafez1' }, { name: 'Hafez2' }]);
 
       yield User.bulkWrite([
-        { updateOne: { filter: { _id: user1._id }, update: { name: 'John1' }, timestamps: false } },
-        { updateMany: { filter: { _id: user2._id }, update: { name: 'John2' }, timestamps: false } }
+        { updateOne: { filter: { _id: users[0]._id }, update: { name: 'John1' }, timestamps: false } },
+        { updateMany: { filter: { _id: users[1]._id }, update: { name: 'John2' }, timestamps: false } }
       ]);
 
-      const [updatedUser1, updatedUser2] = yield Promise.all([
-        User.findOne({ _id: user1._id }),
-        User.findOne({ _id: user2._id })
+      const usersAfterUpdate = yield Promise.all([
+        User.findOne({ _id: users[0]._id }),
+        User.findOne({ _id: users[1]._id })
       ]);
 
-      assert.deepEqual(user1.updatedAt, updatedUser1.updatedAt);
-      assert.deepEqual(user2.updatedAt, updatedUser2.updatedAt);
+      assert.deepEqual(users[0].updatedAt, usersAfterUpdate[0].updatedAt);
+      assert.deepEqual(users[1].updatedAt, usersAfterUpdate[1].updatedAt);
     });
   });
 });

From 13c9e6bdf74d6b08a5c319a61e1fb332d2071301 Mon Sep 17 00:00:00 2001
From: root <roja@e-builder.net>
Date: Thu, 2 Apr 2020 09:59:13 -0400
Subject: [PATCH 0651/2348] updated mpath package version to 0.7.0

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 10fa330fa0d..e350fa9d352 100644
--- a/package.json
+++ b/package.json
@@ -23,7 +23,7 @@
     "kareem": "2.3.1",
     "mongodb": "3.5.5",
     "mongoose-legacy-pluralize": "1.0.2",
-    "mpath": "0.6.0",
+    "mpath": "0.7.0",
     "mquery": "3.2.2",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",

From 7d8e720a5c1f31f6cc1634ae2b3b3a847cd39ab1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Apr 2020 19:12:51 -0400
Subject: [PATCH 0652/2348] chore: remove unused promise-debug module

---
 package.json   | 1 -
 test/common.js | 5 -----
 2 files changed, 6 deletions(-)

diff --git a/package.json b/package.json
index e350fa9d352..24286b6a169 100644
--- a/package.json
+++ b/package.json
@@ -56,7 +56,6 @@
     "mongoose-long": "0.2.1",
     "node-static": "0.7.11",
     "object-sizeof": "1.3.0",
-    "promise-debug": "0.1.1",
     "pug": "2.0.3",
     "q": "1.5.1",
     "semver": "5.5.0",
diff --git a/test/common.js b/test/common.js
index 68ef4b44f0c..170375aa6b8 100644
--- a/test/common.js
+++ b/test/common.js
@@ -230,11 +230,6 @@ beforeEach(function() {
   }
 });
 
-if (process.env.D === '1') {
-  global.Promise = require('promise-debug');
-  mongoose.Promise = require('promise-debug');
-}
-
 process.on('unhandledRejection', function(error, promise) {
   if (error.$expected) {
     return;

From 4979a0abbb253b328a3d424036327eac4bd175c1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 3 Apr 2020 13:53:18 +0200
Subject: [PATCH 0653/2348] test: repro #8739

---
 test/document.test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 0df52d22aea..f76276941f5 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2077,6 +2077,26 @@ describe('document', function() {
         assert.equal(threw, true);
       });
     });
+
+    it('passes save custom options to Model.exists(...) when no changes are present', function() {
+      const personSchema = new Schema({ name: String });
+
+      let optionInMiddleware;
+
+      personSchema.pre('findOne', function(next) {
+        optionInMiddleware = this.getOptions().customOption;
+
+        return next();
+      });
+
+      const Person = db.model('Person', personSchema);
+      return co(function*() {
+        const person = yield Person.create({ name: 'Hafez' });
+        yield person.save({ customOption: 'test' });
+
+        assert.equal(optionInMiddleware, 'test');
+      });
+    });
   });
 
   it('properly calls queue functions (gh-2856)', function(done) {

From b9cd43136b276a4a4e2c828c59462f7951ee0072 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 3 Apr 2020 13:58:54 +0200
Subject: [PATCH 0654/2348] Pass custom options from save to Model.exists(...)

---
 lib/model.js          | 3 ++-
 test/document.test.js | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 13ad9e5f871..c6212058f64 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -314,7 +314,8 @@ Model.prototype.$__handleSave = function(options, callback) {
         callback(null, ret);
       });
     } else {
-      this.constructor.exists(this.$__where(), saveOptions)
+      const optionsWithCustomValues = Object.assign({}, options, saveOptions);
+      this.constructor.exists(this.$__where(), optionsWithCustomValues)
         .then((documentExists)=>{
           if (!documentExists) throw new DocumentNotFoundError(this.$__where(), this.constructor.modelName);
 
diff --git a/test/document.test.js b/test/document.test.js
index f76276941f5..ef50b5ed08f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2078,7 +2078,7 @@ describe('document', function() {
       });
     });
 
-    it('passes save custom options to Model.exists(...) when no changes are present', function() {
+    it('passes save custom options to Model.exists(...) when no changes are present (gh-8739)', function() {
       const personSchema = new Schema({ name: String });
 
       let optionInMiddleware;

From 330e2f5008d03d29f03ab30cb6ba4e433a43b31f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Apr 2020 11:06:23 -0400
Subject: [PATCH 0655/2348] test(map): repro #8730

---
 test/types.map.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index 666eab716ba..7fdf2a1ef17 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -844,4 +844,28 @@ describe('Map', function() {
       assert.equal(fromDb.docMap.get('firstOfficer').name, 'Will Riker');
     });
   });
+
+  it('runs getters on map values (gh-8730)', function() {
+    const schema = mongoose.Schema({
+      name: String,
+      books: {
+        type: Map,
+        of: {
+          type: String,
+          get: function(v) { return `${v}, by ${this.name}`; }
+        }
+      }
+    });
+    const Model = db.model('Test', schema);
+
+    const doc = new Model({
+      name: 'Ian Fleming',
+      books: {
+        'casino-royale': 'Casino Royale'
+      }
+    });
+
+    assert.equal(doc.books.get('casino-royale'), 'Casino Royale, by Ian Fleming');
+    assert.equal(doc.get('books.casino-royale'), 'Casino Royale, by Ian Fleming');
+  });
 });

From 5ea395a0aac89792d77df2dad8e19dbbae97e00a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Apr 2020 11:06:34 -0400
Subject: [PATCH 0656/2348] fix(map): run getters when calling  `Map#get()`

Fix #8730
---
 lib/document.js  | 2 +-
 lib/types/map.js | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index aaa62ff530c..3b0a7ad0884 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1528,7 +1528,7 @@ Document.prototype.get = function(path, type, options) {
     if (obj == null) {
       obj = void 0;
     } else if (obj instanceof Map) {
-      obj = obj.get(pieces[i]);
+      obj = obj.get(pieces[i], { getters: false });
     } else if (i === l - 1) {
       obj = utils.getValue(pieces[i], obj);
     } else {
diff --git a/lib/types/map.js b/lib/types/map.js
index df32be82137..bebd8db8567 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -41,6 +41,14 @@ class MongooseMap extends Map {
     super.set(key, value);
   }
 
+  get(key, options) {
+    options = options || {};
+    if (options.getters === false) {
+      return super.get(key);
+    }
+    return this.$__schemaType.applyGetters(super.get(key), this.$__parent);
+  }
+
   set(key, value) {
     checkValidKey(key);
     value = handleSpreadDoc(value);

From 00346c07128fa6cec560652e7ddff2e2eebd67d4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Apr 2020 13:34:13 -0400
Subject: [PATCH 0657/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 76b97798685..ce3fb6677e2 100644
--- a/index.pug
+++ b/index.pug
@@ -304,6 +304,9 @@ html(lang='en')
               <a href="https://casinoonline.casino/">
                 <img class="sponsor" src="https://images.opencollective.com/casino-online/4c8371c/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.casinot.net/">
+                <img class="sponsor" src="https://images.opencollective.com/casinot-net/242597a/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From f4f3192ed5957a83f33698c6f6bc4f7fc06fb7c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Apr 2020 13:52:18 -0400
Subject: [PATCH 0658/2348] test: repro #8731

---
 test/model.populate.test.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index c9e8104ca9b..241b8f1fb05 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9243,4 +9243,34 @@ describe('model: populate:', function() {
       assert.equal(err.message, 'Can not use `limit` and `perDocumentLimit` at the same time. Path: `blogposts`.');
     });
   });
+
+  it('handles function refPath with discriminators (gh-8731)', function() {
+    return co(function *() {
+      const nested = Schema({}, { discriminatorKey: 'type' });
+      const mainSchema = Schema({ items: [nested] });
+
+      mainSchema.path('items').discriminator('TestDiscriminator', Schema({
+        childModel: { type: String },
+        child: {
+          type: mongoose.Schema.Types.ObjectId,
+          refPath: (doc, path) => path.replace('.child', '.childModel')
+        }
+      }));
+      const Parent = db.model('Parent', mainSchema);
+      const Child = db.model('Child', Schema({ name: String }));
+
+      const child = yield Child.create({ name: 'test' });
+      yield Parent.create({
+        items: [{
+          type: 'TestDiscriminator',
+          childModel: 'Child',
+          child: child._id
+        }]
+      });
+
+      const doc = yield Parent.findOne().populate('items.child').exec();
+      assert.equal(doc.items[0].child.name, 'test');
+      assert.ok(doc.items[0].populated('child'));
+    });
+  });
 });
\ No newline at end of file

From 16fe0cd39d0b19dae162e2293c1a0b2ec8df7d1c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Apr 2020 13:52:31 -0400
Subject: [PATCH 0659/2348] fix(populate): handle `refPath` function in
 embedded discriminator

Fix #8731
---
 lib/helpers/populate/getModelsMapForPopulate.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index abc0e6eb2d5..4edad56f164 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -60,7 +60,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           res = _getModelNames(doc, schema[j]);
           _modelNames = res.modelNames;
           isRefPath = isRefPath || res.isRefPath;
-          normalizedRefPath = normalizedRefPath || res.refPath;
+          normalizedRefPath = normalizeRefPath(normalizedRefPath, doc, options.path) ||
+            res.refPath;
         } catch (error) {
           return error;
         }

From cadd7be5343f1beb6615135971a9a0f91527c2ad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Apr 2020 15:23:45 -0400
Subject: [PATCH 0660/2348] test(update): repro #8735

---
 test/model.update.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 17a7444346e..e0051085378 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3339,6 +3339,25 @@ describe('model: updateOne: ', function() {
     });
   });
 
+  it('respects useNestedStrict: false when updating a single nested path (gh-8735)', function() {
+    const emptySchema = Schema({}, {
+      strict : false,
+      _id : false,
+      versionKey : false
+    });
+
+    const testSchema = Schema({
+      test: String,
+      nested: emptySchema
+    }, { strict: true, versionKey: false, useNestedStrict: false });
+    const Test = db.model('Test', testSchema);
+
+    const update = { nested: { notInSchema: 'bar' } };
+    return Test.updateOne({ test: 'foo' }, update, { upsert: true }).
+      then(() => Test.collection.findOne()).
+      then(doc => assert.strictEqual(doc.nested.notInSchema, void 0));
+  });
+
   describe('mongodb 42 features', function() {
     before(function(done) {
       start.mongodVersion((err, version) => {

From f0284bc424658e3987d447e1fe5fd0a95ccfb0c2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Apr 2020 15:25:09 -0400
Subject: [PATCH 0661/2348] fix(update): respect `useNestedStrict: false` when
 updating a single nested path

Fix #8735
---
 lib/document.js                 |  4 ++--
 lib/helpers/query/castUpdate.js | 24 ++++++++++++++++++++----
 lib/schema/SingleNestedPath.js  |  7 +++++--
 lib/schematype.js               |  2 +-
 test/model.update.test.js       |  4 ++--
 5 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 3b0a7ad0884..269bfc9d55e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -91,7 +91,7 @@ function Document(obj, fields, skipId, options) {
 
   const schema = this.schema;
 
-  if (typeof fields === 'boolean') {
+  if (typeof fields === 'boolean' || fields === 'throw') {
     this.$__.strictMode = fields;
     fields = undefined;
   } else {
@@ -160,7 +160,7 @@ function Document(obj, fields, skipId, options) {
   this.$locals = {};
   this.$op = null;
 
-  if (!schema.options.strict && obj) {
+  if (!this.$__.strictMode && obj) {
     const _this = this;
     const keys = Object.keys(this._doc);
 
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index b45f6d1863c..951aa8840a2 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -221,10 +221,26 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
             obj[key].$position = castNumber(val.$position);
           }
         } else {
-          try {
-            obj[key] = castUpdateVal(schematype, val, op, key, context, prefix + key);
-          } catch (error) {
-            aggregatedError = _handleCastError(error, context, key, aggregatedError);
+          if (schematype != null && schematype.$isSingleNested) {
+            // Special case to make sure `strict` bubbles down correctly to
+            // single nested re: gh-8735
+            let _strict = strict;
+            if (useNestedStrict && schematype.schema.options.hasOwnProperty('strict')) {
+              _strict = schematype.schema.options.strict;
+            } else if (useNestedStrict === false) {
+              _strict = schema.options.strict;
+            }
+            try {
+              obj[key] = schematype.castForQuery(val, context, { strict: _strict });
+            } catch (error) {
+              aggregatedError = _handleCastError(error, context, key, aggregatedError);
+            }
+          } else {
+            try {
+              obj[key] = castUpdateVal(schematype, val, op, key, context, prefix + key);
+            } catch (error) {
+              aggregatedError = _handleCastError(error, context, key, aggregatedError);
+            }
           }
 
           if (options.omitUndefined && obj[key] === void 0) {
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 9ac29710ec6..d7abd6cea77 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -192,7 +192,7 @@ SingleNestedPath.prototype.cast = function(val, doc, init, priorVal) {
  * @api private
  */
 
-SingleNestedPath.prototype.castForQuery = function($conditional, val) {
+SingleNestedPath.prototype.castForQuery = function($conditional, val, options) {
   let handler;
   if (arguments.length === 2) {
     handler = this.$conditionalHandlers[$conditional];
@@ -211,9 +211,12 @@ SingleNestedPath.prototype.castForQuery = function($conditional, val) {
   }
 
   const Constructor = getConstructor(this.caster, val);
+  const overrideStrict = options != null && options.strict != null ?
+    options.strict :
+    void 0;
 
   try {
-    val = new Constructor(val);
+    val = new Constructor(val, overrideStrict);
   } catch (error) {
     // Make sure we always wrap in a CastError (gh-6803)
     if (!(error instanceof CastError)) {
diff --git a/lib/schematype.js b/lib/schematype.js
index c1e197b4374..05e105a549e 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1305,7 +1305,7 @@ SchemaType._isRef = function(self, value, doc, init) {
     // - this populated with adhoc model and no ref was set in schema OR
     // - setting / pushing values after population
     const path = doc.$__fullPath(self.path);
-    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
+    let owner = doc.ownerDocument ? doc.ownerDocument() : doc;
     ref = owner.populated(path) || doc.populated(self.path);
   }
 
diff --git a/test/model.update.test.js b/test/model.update.test.js
index e0051085378..4a5d5af3390 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3341,8 +3341,8 @@ describe('model: updateOne: ', function() {
 
   it('respects useNestedStrict: false when updating a single nested path (gh-8735)', function() {
     const emptySchema = Schema({}, {
-      strict : false,
-      _id : false,
+      strict: false,
+      _id: false,
       versionKey : false
     });
 

From 2da90e2ef4a1789481cd00c022f8727a543ffb29 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Apr 2020 15:43:00 -0400
Subject: [PATCH 0662/2348] style: fix lint

---
 lib/schematype.js         | 2 +-
 test/model.update.test.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index 05e105a549e..c1e197b4374 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1305,7 +1305,7 @@ SchemaType._isRef = function(self, value, doc, init) {
     // - this populated with adhoc model and no ref was set in schema OR
     // - setting / pushing values after population
     const path = doc.$__fullPath(self.path);
-    let owner = doc.ownerDocument ? doc.ownerDocument() : doc;
+    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
     ref = owner.populated(path) || doc.populated(self.path);
   }
 
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 4a5d5af3390..78471381860 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3343,7 +3343,7 @@ describe('model: updateOne: ', function() {
     const emptySchema = Schema({}, {
       strict: false,
       _id: false,
-      versionKey : false
+      versionKey: false
     });
 
     const testSchema = Schema({

From 984173b14431b6447dfb774719c433b19b670bec Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Apr 2020 14:53:33 -0400
Subject: [PATCH 0663/2348] docs(promises): add section about using `exec()`
 with queries and `await`

Fix #8747
---
 docs/source/acquit.js             |   2 +-
 test/docs/promises.test.js        |  14 +++
 test/es-next.test.js              |   1 +
 test/es-next/promises.test.es6.js | 181 ++++++++++++++++++++++++++++++
 4 files changed, 197 insertions(+), 1 deletion(-)
 create mode 100644 test/es-next/promises.test.es6.js

diff --git a/docs/source/acquit.js b/docs/source/acquit.js
index 7b8ca47c1e1..ad378070642 100644
--- a/docs/source/acquit.js
+++ b/docs/source/acquit.js
@@ -18,7 +18,7 @@ var files = [
     title: 'Discriminators'
   },
   {
-    input: 'test/docs/promises.test.js',
+    input: 'test/es-next/promises.test.es6.js',
     output: 'promises.html',
     title: 'Promises',
     suffix: `
diff --git a/test/docs/promises.test.js b/test/docs/promises.test.js
index cbea914055e..a6d82d04f80 100644
--- a/test/docs/promises.test.js
+++ b/test/docs/promises.test.js
@@ -99,6 +99,20 @@ describe('promises docs', function () {
       // acquit:ignore:end
     });
   });
+
+  /**
+   * There are two alternatives for using `await` with queries:
+   * 
+   * - `await Band.findOne();`
+   * - `await Band.findOne().exec();`
+   * 
+   * As far as functionality is concerned, these two are equivalent.
+   * However, we recommend using `.exec()` because that gives you
+   * better stack traces.
+   */
+  it('Should You Use `exec()` With `await`?', function() {
+    
+  });
   
   /**
    * If you're an advanced user, you may want to plug in your own promise
diff --git a/test/es-next.test.js b/test/es-next.test.js
index bf26b4ca365..2fb5cae2186 100644
--- a/test/es-next.test.js
+++ b/test/es-next.test.js
@@ -9,5 +9,6 @@ if (parseInt(process.versions.node.split('.')[0], 10) >= 8) {
   require('./es-next/cast.test.es6.js');
   require('./es-next/findoneandupdate.test.es6.js');
   require('./es-next/getters-setters.test.es6.js');
+  require('./es-next/promises.test.es6.js');
   require('./es-next/virtuals.test.es6.js');
 }
diff --git a/test/es-next/promises.test.es6.js b/test/es-next/promises.test.es6.js
new file mode 100644
index 00000000000..a9b33d50c7b
--- /dev/null
+++ b/test/es-next/promises.test.es6.js
@@ -0,0 +1,181 @@
+'use strict';
+var PromiseProvider = require('../../lib/promise_provider');
+var assert = require('assert');
+var mongoose = require('../../');
+
+describe('promises docs', function () {
+  var Band;
+  var db;
+
+  before(function (done) {
+    db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
+
+    Band = db.model('band-promises', {name: String, members: [String]});
+
+    done();
+  });
+
+  beforeEach(function (done) {
+    Band.deleteMany({}, done);
+  });
+
+  after(function (done) {
+    db.close(done);
+  });
+
+  /**
+   * Mongoose async operations, like `.save()` and queries, return thenables.
+   * This means that you can do things like `MyModel.findOne({}).then()` and
+   * `await MyModel.findOne({}).exec()` if you're using
+   * [async/await](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html).
+   * 
+   * You can find the return type of specific operations [in the api docs](https://mongoosejs.com/docs/api.html)
+   * You can also read more about [promises in Mongoose](https://masteringjs.io/tutorials/mongoose/promise).
+   */
+  it('Built-in Promises', function (done) {
+    var gnr = new Band({
+      name: "Guns N' Roses",
+      members: ['Axl', 'Slash']
+    });
+
+    var promise = gnr.save();
+    assert.ok(promise instanceof Promise);
+
+    promise.then(function (doc) {
+      assert.equal(doc.name, "Guns N' Roses");
+      // acquit:ignore:start
+      done();
+      // acquit:ignore:end
+    });
+  });
+
+  /**
+   * [Mongoose queries](http://mongoosejs.com/docs/queries.html) are **not** promises. They have a `.then()`
+   * function for [co](https://www.npmjs.com/package/co) and async/await as
+   * a convenience. If you need
+   * a fully-fledged promise, use the `.exec()` function.
+   */
+  it('Queries are not promises', function (done) {
+    var query = Band.findOne({name: "Guns N' Roses"});
+    assert.ok(!(query instanceof Promise));
+
+    // acquit:ignore:start
+    var outstanding = 2;
+    // acquit:ignore:end
+
+    // A query is not a fully-fledged promise, but it does have a `.then()`.
+    query.then(function (doc) {
+      // use doc
+      // acquit:ignore:start
+      assert.ok(!doc);
+      --outstanding || done();
+      // acquit:ignore:end
+    });
+
+    // `.exec()` gives you a fully-fledged promise
+    var promise = query.exec();
+    assert.ok(promise instanceof Promise);
+
+    promise.then(function (doc) {
+      // use doc
+      // acquit:ignore:start
+      assert.ok(!doc);
+      --outstanding || done();
+      // acquit:ignore:end
+    });
+  });
+
+  /**
+   * Although queries are not promises, queries are [thenables](https://promisesaplus.com/#terminology).
+   * That means they have a `.then()` function, so you can use queries as promises with either
+   * promise chaining or [async await](https://asyncawait.net)
+   */
+  it('Queries are thenable', function (done) {
+    Band.findOne({name: "Guns N' Roses"}).then(function(doc) {
+      // use doc
+      // acquit:ignore:start
+      assert.ok(!doc);
+      done();
+      // acquit:ignore:end
+    });
+  });
+
+  /**
+   * There are two alternatives for using `await` with queries:
+   * 
+   * - `await Band.findOne();`
+   * - `await Band.findOne().exec();`
+   * 
+   * As far as functionality is concerned, these two are equivalent.
+   * However, we recommend using `.exec()` because that gives you
+   * better stack traces.
+   */
+  it('Should You Use `exec()` With `await`?', async function() {
+    const doc = await Band.findOne({ name: "Guns N' Roses" }); // works
+    // acquit:ignore:start
+    assert.ok(!doc);
+    // acquit:ignore:end
+
+    const badId = 'this is not a valid id';
+    try {
+      await Band.findOne({ _id: badId });
+    } catch (err) {
+      // Without `exec()`, the stack trace does **not** include the
+      // calling code. Below is the stack trace:
+      //
+      // CastError: Cast to ObjectId failed for value "this is not a valid id" at path "_id" for model "band-promises"
+      //   at new CastError (/app/node_modules/mongoose/lib/error/cast.js:29:11)
+      //   at model.Query.exec (/app/node_modules/mongoose/lib/query.js:4331:21)
+      //   at model.Query.Query.then (/app/node_modules/mongoose/lib/query.js:4423:15)
+      //   at process._tickCallback (internal/process/next_tick.js:68:7)
+      err.stack;
+      // acquit:ignore:start
+      assert.ok(!err.stack.includes('promises.test.es6.js'));
+      // acquit:ignore:end
+    }
+
+    try {
+      await Band.findOne({ _id: badId }).exec();
+    } catch (err) {
+      // With `exec()`, the stack trace includes where in your code you
+      // called `exec()`. Below is the stack trace:
+      //
+      // CastError: Cast to ObjectId failed for value "this is not a valid id" at path "_id" for model "band-promises"
+      //   at new CastError (/app/node_modules/mongoose/lib/error/cast.js:29:11)
+      //   at model.Query.exec (/app/node_modules/mongoose/lib/query.js:4331:21)
+      //   at Context.<anonymous> (/app/test/index.test.js:138:42)
+      //   at process._tickCallback (internal/process/next_tick.js:68:7)
+      err.stack;
+      // acquit:ignore:start
+      assert.ok(err.stack.includes('promises.test.es6.js'));
+      // acquit:ignore:end
+    }
+  });
+  
+  /**
+   * If you're an advanced user, you may want to plug in your own promise
+   * library like [bluebird](https://www.npmjs.com/package/bluebird). Just set
+   * `mongoose.Promise` to your favorite
+   * ES6-style promise constructor and mongoose will use it.
+   */
+  it('Plugging in your own Promises Library', function (done) {
+    // acquit:ignore:start
+    if (!global.Promise) {
+      return done();
+    }
+    // acquit:ignore:end
+    var query = Band.findOne({name: "Guns N' Roses"});
+
+    // Use bluebird
+    mongoose.Promise = require('bluebird');
+    assert.equal(query.exec().constructor, require('bluebird'));
+
+    // Use q. Note that you **must** use `require('q').Promise`.
+    mongoose.Promise = require('q').Promise;
+    assert.ok(query.exec() instanceof require('q').makePromise);
+
+    // acquit:ignore:start
+    done();
+    // acquit:ignore:end
+  });
+});

From 2238af62905329202609bce45934082a78aed96d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Apr 2020 10:13:36 -0400
Subject: [PATCH 0664/2348] test: fix tests

---
 test/es-next/promises.test.es6.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/es-next/promises.test.es6.js b/test/es-next/promises.test.es6.js
index a9b33d50c7b..4926c1f109e 100644
--- a/test/es-next/promises.test.es6.js
+++ b/test/es-next/promises.test.es6.js
@@ -20,6 +20,8 @@ describe('promises docs', function () {
   });
 
   after(function (done) {
+    mongoose.Promise = global.Promise;
+
     db.close(done);
   });
 

From b698b00bd54ef03fb161305428e17206ef016d13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Apr 2020 10:23:34 -0400
Subject: [PATCH 0665/2348] docs(connections): clarify that `connectTimeoutMS`
 doesn't do anything with `useUnifiedTopology`, should use
 `serverSelectionTimeoutMS`

Fix #8721
---
 docs/connections.pug | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 3767aca5db0..7bf730cbdc0 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -167,7 +167,6 @@ block content
     * `useUnifiedTopology`- False by default. Set to `true` to opt in to using [the MongoDB driver's new connection management engine](/docs/deprecations.html#useunifiedtopology). You should set this option to `true`, except for the unlikely case that it prevents you from maintaining a stable connection.
     * `promiseLibrary`    - Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
     * `poolSize`          - The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
-    * `connectTimeoutMS`  - How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
     * `socketTimeoutMS`   - How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
     * `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
     * `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
@@ -179,11 +178,19 @@ block content
     * `reconnectTries`    - If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
     * `reconnectInterval` - See `reconnectTries`
     * `bufferMaxEntries`  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
+    * `connectTimeoutMS`  - How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
 
     The following options are important for tuning Mongoose only if you are
     running **with** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
 
     * `serverSelectionTimeoutMS` - With `useUnifiedTopology`, the MongoDB driver will try to find a server to send any given operation to, and keep retrying for `serverSelectionTimeoutMS` milliseconds. If not set, the MongoDB driver defaults to using `30000` (30 seconds).
+    * `heartbeatFrequencyMS` - With `useUnifiedTopology`, the MongoDB driver sends a heartbeat every `heartbeatFrequencyMS` to check on the status of the connection. A heartbeat is subject to `serverSelectionTimeoutMS`, so the MongoDB driver will retry failed heartbeats for up to 30 seconds by default. Mongoose only emits a `'disconnected'` event after a heartbeat has failed, so you may want to decrease this setting to reduce the time between when your server goes down and when Mongoose emits `'disconnected'`. We recommend you do **not** set this setting below 1000, too many heartbeats can lead to performance degradation.
+
+    The `serverSelectionTimeoutMS` option also handles how long `mongoose.connect()` will
+    retry initial connection before erroring out. With `useUnifiedTopology`, `mongoose.connect()`
+    will retry for 30 seconds by default (default `serverSelectionTimeoutMS`) before
+    erroring out. To get faster feedback on failed operations, you can reduce `serverSelectionTimeoutMS`
+    to 5000 as shown below.
 
     Example:
 

From 80da55846b969aefa3d9f9eb9b6ae6de69207bcb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Apr 2020 10:48:48 -0400
Subject: [PATCH 0666/2348] fix(schema): allow `modelName` as a schema path,
 since `modelName` is a static property on models

Fix #7967
Re: https://github.com/Automattic/mongoose/commit/1975355f3f35285fe98df3362545c7a92ede35b2
Re: #928
---
 lib/schema.js       | 1 -
 test/schema.test.js | 6 ------
 2 files changed, 7 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 16b0ad46654..4fa8f9408ba 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -584,7 +584,6 @@ reserved.init =
 reserved.isModified =
 reserved.isNew =
 reserved.get =
-reserved.modelName =
 reserved.save =
 reserved.schema =
 reserved.toObject =
diff --git a/test/schema.test.js b/test/schema.test.js
index 3ffe4fdef58..b5e5624f672 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1440,12 +1440,6 @@ describe('schema', function() {
         });
       }, /`db` may not be used as a schema pathname/);
 
-      assert.throws(function() {
-        new Schema({
-          modelName: String
-        });
-      }, /`modelName` may not be used as a schema pathname/);
-
       assert.throws(function() {
         new Schema({
           isNew: String

From 2176734ca7a6f12f0031432879ac9ca76715792c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Apr 2020 11:11:50 -0400
Subject: [PATCH 0667/2348] docs: add builder book to "built with mongoose"

Fix #8771
---
 docs/built-with-mongoose.pug | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
index 9a21901d80c..dbc48511c0b 100644
--- a/docs/built-with-mongoose.pug
+++ b/docs/built-with-mongoose.pug
@@ -43,11 +43,31 @@ block content
         </a>
       </div>
       <div style="padding-left: 110px; min-height: 100px">
-        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">Mixmax</a></h3>
+        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
+          <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
+            Mixmax
+          </a>
+        </h4>
         Mixmax is a app that sends engaging emails with instant scheduling, free unlimited email tracking, polls, and surveys right in Gmail.
       </div>
     </div>
 
+    <div style="position: relative; margin-top: 1em;">
+      <div style="position: absolute; width: 100px; height: 100px">
+        <a href="http://builderbook.org/">
+          <img src="https://storage.googleapis.com/builderbook/logo.svg">
+        </a>
+      </div>
+      <div style="padding-left: 110px; min-height: 100px">
+        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
+          <a href="http://builderbook.org/">
+            Builder Book
+          </a>
+        </h4>
+        Learn how to build a full-stack, production-ready JavaScript web application from scratch. You'll go from 0 lines of code in Chapter 1 to over 10,000 lines of code by Chapter 8.
+      </div>
+    </div>
+
     ## Add Your Own
 
     Have an app that you built with Mongoose that you want to feature here?

From e2615d82048d65dec4849e11c692ea61e3b10a56 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Apr 2020 17:34:02 -0400
Subject: [PATCH 0668/2348] chore: release 5.9.8

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 1c67ef0a43e..2831a6f7d6a 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.9.8 / 2020-04-06
+==================
+ * fix(map): run getters when calling `Map#get()` #8730
+ * fix(populate): handle `refPath` function in embedded discriminator #8731
+ * fix(model): allow setting timestamps to false for bulkWrite #8758 #8745 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(model): pass custom options to `exists()` when no changes to save #8764 #8739 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(update): respect `useNestedStrict: false` when updating a single nested path #8735
+ * fix(schema): allow `modelName` as a schema path, since `modelName` is a static property on models #7967
+ * docs(promises): add section about using `exec()` with queries and `await` #8747
+ * docs(connections): clarify that `connectTimeoutMS` doesn't do anything with `useUnifiedTopology`, should use `serverSelectionTimeoutMS` #8721
+ * chore: upgrade mpath -> 0.7.0 #8762 [roja548](https://github.com/roja548)
+
 5.9.7 / 2020-03-30
 ==================
  * fix(map): avoid infinite loop when setting a map of documents to a document copied using spread operator #8722
diff --git a/package.json b/package.json
index 24286b6a169..f2170ad6769 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.7",
+  "version": "5.9.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9ce000ce07c917dbf8a298d5fceac173f1796c28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Apr 2020 11:17:52 -0400
Subject: [PATCH 0669/2348] test: buffer operations on test models after test
 is done to prevent modifying db after test is finished

Fix #8710
---
 lib/connection.js                             | 3 ++-
 lib/drivers/node-mongodb-native/collection.js | 2 ++
 test/aggregate.test.js                        | 2 +-
 test/document.modified.test.js                | 1 +
 test/document.populate.test.js                | 2 +-
 test/document.strict.test.js                  | 1 +
 test/document.test.js                         | 1 +
 test/geojson.test.js                          | 1 +
 test/model.discriminator.querying.test.js     | 1 +
 test/model.discriminator.test.js              | 1 +
 test/model.field.selection.test.js            | 1 +
 test/model.findOneAndDelete.test.js           | 1 +
 test/model.findOneAndRemove.test.js           | 1 +
 test/model.findOneAndReplace.test.js          | 1 +
 test/model.findOneAndUpdate.test.js           | 1 +
 test/model.indexes.test.js                    | 1 +
 test/model.middleware.test.js                 | 1 +
 test/model.populate.test.js                   | 2 +-
 test/model.query.casting.test.js              | 1 +
 test/model.querying.test.js                   | 2 +-
 test/model.test.js                            | 1 +
 test/model.update.test.js                     | 3 ++-
 test/plugin.idGetter.test.js                  | 1 +
 test/query.cursor.test.js                     | 1 +
 test/query.middleware.test.js                 | 1 +
 test/query.test.js                            | 2 +-
 test/schema.alias.test.js                     | 1 +
 test/schema.onthefly.test.js                  | 1 +
 test/schema.select.test.js                    | 1 +
 test/schema.test.js                           | 1 +
 test/timestamps.test.js                       | 1 +
 test/types.array.test.js                      | 1 +
 test/types.buffer.test.js                     | 1 +
 test/types.documentarray.test.js              | 1 +
 test/types.map.test.js                        | 1 +
 test/util.js                                  | 9 +++++++++
 test/versioning.test.js                       | 1 +
 37 files changed, 48 insertions(+), 7 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 2bdfa698fe0..bcbaf9c157d 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1139,8 +1139,9 @@ Connection.prototype.deleteModel = function(name) {
     if (model == null) {
       return this;
     }
+    const collectionName = model.collection.name;
     delete this.models[name];
-    delete this.collections[model.collection.name];
+    delete this.collections[collectionName];
     delete this.base.modelSchemas[name];
   } else if (name instanceof RegExp) {
     const pattern = name;
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 7f0be874031..d868188ec3f 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -24,6 +24,7 @@ const util = require('util');
 function NativeCollection(name, options) {
   this.collection = null;
   this.Promise = options.Promise || Promise;
+  this._closed = false;
   MongooseCollection.apply(this, arguments);
 }
 
@@ -138,6 +139,7 @@ function iter(i) {
         throw error;
       }
     }
+
     if (this.buffer) {
       if (syncCollectionMethods[i]) {
         throw new Error('Collection method ' + i + ' is synchronous');
diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index a9a9bcf49ed..9dcfdc278c2 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -93,8 +93,8 @@ describe('aggregate: ', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('append', function() {
     it('(pipeline)', function(done) {
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index cf0a4e30cfd..0d344d8d61c 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -26,6 +26,7 @@ describe('document modified', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     const Comments = new Schema;
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index a351fb3f617..654aa7f93e5 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -108,8 +108,8 @@ describe('document.populate', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function(done) {
     B = db.model('BlogPost', BlogPostSchema);
diff --git a/test/document.strict.test.js b/test/document.strict.test.js
index 145af35c9e3..2a98ec12072 100644
--- a/test/document.strict.test.js
+++ b/test/document.strict.test.js
@@ -25,6 +25,7 @@ describe('document: strict mode:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('should work', function() {
     let Lax, Strict;
diff --git a/test/document.test.js b/test/document.test.js
index ef50b5ed08f..b90ce98c847 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -134,6 +134,7 @@ describe('document', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => util.clearTestData(db));
+  afterEach(() => util.stopRemainingOps(db));
 
   describe('constructor', function() {
     it('supports passing in schema directly (gh-8237)', function() {
diff --git a/test/geojson.test.js b/test/geojson.test.js
index 8b7caadd84c..36aa46df4e3 100644
--- a/test/geojson.test.js
+++ b/test/geojson.test.js
@@ -37,6 +37,7 @@ describe('geojson', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('driver query', function() {
     const City = db.model('City', new Schema({
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 95eb92798d9..1786b57d2a5 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -52,6 +52,7 @@ describe('model', function() {
     });
 
     afterEach(() => require('./util').clearTestData(db));
+    afterEach(() => require('./util').stopRemainingOps(db));
 
     after(function(done) {
       db.close(done);
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 25349b5ce1c..399eed460c7 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -76,6 +76,7 @@ describe('model', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('discriminator()', function() {
     var Person, Employee;
diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index cca7e540dd4..407aeeb87d2 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -29,6 +29,7 @@ describe('model field selection', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.findOneAndDelete.test.js b/test/model.findOneAndDelete.test.js
index 04ac46f8210..ea653fd5918 100644
--- a/test/model.findOneAndDelete.test.js
+++ b/test/model.findOneAndDelete.test.js
@@ -29,6 +29,7 @@ describe('model: findOneAndDelete:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.findOneAndRemove.test.js b/test/model.findOneAndRemove.test.js
index d6e179f895b..d7a34b3b71b 100644
--- a/test/model.findOneAndRemove.test.js
+++ b/test/model.findOneAndRemove.test.js
@@ -29,6 +29,7 @@ describe('model: findOneAndRemove:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.findOneAndReplace.test.js b/test/model.findOneAndReplace.test.js
index 6b203a6c350..8846b919a4a 100644
--- a/test/model.findOneAndReplace.test.js
+++ b/test/model.findOneAndReplace.test.js
@@ -29,6 +29,7 @@ describe('model: findOneAndReplace:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 1814a8d56d1..b934faf9e7a 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -35,6 +35,7 @@ describe('model: findOneAndUpdate:', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema();
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 6d08cb8f71f..5de1a347da0 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -29,6 +29,7 @@ describe('model', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('indexes', function() {
     this.timeout(5000);
diff --git a/test/model.middleware.test.js b/test/model.middleware.test.js
index f439c5494ef..bf784000bb7 100644
--- a/test/model.middleware.test.js
+++ b/test/model.middleware.test.js
@@ -25,6 +25,7 @@ describe('model middleware', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('post save', function(done) {
     const schema = new Schema({
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 241b8f1fb05..a3c203af156 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -68,8 +68,8 @@ describe('model: populate:', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('populating array of object', function(done) {
     const BlogPost = db.model('BlogPost', blogPostSchema);
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index c50af33ff55..ad45fbb9889 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -33,6 +33,7 @@ describe('model query casting', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 010845b843f..047db6667f0 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -29,8 +29,8 @@ describe('model: querying:', function() {
   before(() => { db = start(); });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema;
diff --git a/test/model.test.js b/test/model.test.js
index 7e2e573adc9..400538bef86 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -86,6 +86,7 @@ describe('Model', function() {
   });
 
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('can be created using _id as embedded document', function(done) {
     const Test = db.model('Test', Schema({
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 78471381860..d5162e89d41 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -102,8 +102,8 @@ describe('model: update:', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('works', function(done) {
     BlogPost.findById(post._id, function(err, cf) {
@@ -3104,6 +3104,7 @@ describe('model: updateOne: ', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('updating a map (gh-7111)', function() {
     const accountSchema = new Schema({ balance: Number });
diff --git a/test/plugin.idGetter.test.js b/test/plugin.idGetter.test.js
index cb00f2deb17..37f02b340ea 100644
--- a/test/plugin.idGetter.test.js
+++ b/test/plugin.idGetter.test.js
@@ -24,6 +24,7 @@ describe('id virtual getter', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('should work as expected with an ObjectId', function(done) {
     const schema = new Schema({});
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index af474c30754..c38a2327edc 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -26,6 +26,7 @@ describe('QueryCursor', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     const schema = new Schema({ name: String });
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index 3dbf5e3471d..a45ab720158 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -73,6 +73,7 @@ describe('query middleware', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('has a pre find hook', function(done) {
     let count = 0;
diff --git a/test/query.test.js b/test/query.test.js
index 4f974363580..96474a65d1f 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -48,8 +48,8 @@ describe('Query', function() {
   });
 
   beforeEach(() => db.deleteModel(/.*/));
-
   afterEach(() => util.clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('constructor', function() {
     it('should not corrupt options', function(done) {
diff --git a/test/schema.alias.test.js b/test/schema.alias.test.js
index 8df245437b1..9d22f13bbda 100644
--- a/test/schema.alias.test.js
+++ b/test/schema.alias.test.js
@@ -25,6 +25,7 @@ describe('schema alias option', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('works with all basic schema types', function(done) {
     const schema = new Schema({
diff --git a/test/schema.onthefly.test.js b/test/schema.onthefly.test.js
index 5d5afec1952..67411e6aa52 100644
--- a/test/schema.onthefly.test.js
+++ b/test/schema.onthefly.test.js
@@ -26,6 +26,7 @@ describe('schema.onthefly', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('setting should cache the schema type and cast values appropriately', function(done) {
     const Decorated = db.model('Test', DecoratedSchema);
diff --git a/test/schema.select.test.js b/test/schema.select.test.js
index bc9a405f822..43cc1ca5200 100644
--- a/test/schema.select.test.js
+++ b/test/schema.select.test.js
@@ -24,6 +24,7 @@ describe('schema select option', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('excluding paths through schematype', function(done) {
     const schema = new Schema({
diff --git a/test/schema.test.js b/test/schema.test.js
index b5e5624f672..3b8575bc76f 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -56,6 +56,7 @@ describe('schema', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('nested fields with same name', function() {
     let NestedModel;
diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index b54507cb0f6..7a0f3f32273 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -21,6 +21,7 @@ describe('timestamps', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('does not override timestamp params defined in schema (gh-4868)', function(done) {
     const startTime = Date.now();
diff --git a/test/types.array.test.js b/test/types.array.test.js
index ff8bcb0e69f..f2f8aeacee4 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -42,6 +42,7 @@ describe('types array', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('behaves and quacks like an Array', function(done) {
     const a = new MongooseArray;
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index da9d47d292a..308379431cd 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -53,6 +53,7 @@ describe('types.buffer', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('test that a mongoose buffer behaves and quacks like a buffer', function(done) {
     let a = new MongooseBuffer;
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 8b3499cc6de..22d9db368a9 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -62,6 +62,7 @@ describe('types.documentarray', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('behaves and quacks like an array', function(done) {
     const a = new MongooseDocumentArray();
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 7fdf2a1ef17..4d1876a0ab6 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -30,6 +30,7 @@ describe('Map', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   it('validation', function() {
     const nestedValidateCalls = [];
diff --git a/test/util.js b/test/util.js
index 37282ec0257..4b22f5abb40 100644
--- a/test/util.js
+++ b/test/util.js
@@ -13,4 +13,13 @@ exports.clearTestData = function clearTestData(db) {
   }
 
   return Promise.all(arr);
+};
+
+exports.stopRemainingOps = function stopRemainingOps(db) {
+  // Make all future operations on currently defined models hang
+  // forever. Since the collection gets deleted, should get
+  // garbage collected.
+  for (const model of Object.values(db.models)) {
+    model.collection.buffer = true;
+  }
 };
\ No newline at end of file
diff --git a/test/versioning.test.js b/test/versioning.test.js
index bc630056dde..ec3cd6ea64d 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -29,6 +29,7 @@ describe('versioning', function() {
 
   beforeEach(() => db.deleteModel(/.*/));
   afterEach(() => require('./util').clearTestData(db));
+  afterEach(() => require('./util').stopRemainingOps(db));
 
   beforeEach(function() {
     Comments = new Schema();

From 4d45607d0ea23a3a7e8983e18b7ed006f4bf7512 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 7 Apr 2020 11:25:55 -0400
Subject: [PATCH 0670/2348] test: fix tests on older versions of node re: #8710

---
 test/util.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/test/util.js b/test/util.js
index 4b22f5abb40..99d480b90b5 100644
--- a/test/util.js
+++ b/test/util.js
@@ -19,7 +19,8 @@ exports.stopRemainingOps = function stopRemainingOps(db) {
   // Make all future operations on currently defined models hang
   // forever. Since the collection gets deleted, should get
   // garbage collected.
-  for (const model of Object.values(db.models)) {
+  for (const name of Object.keys(db.models)) {
+    const model = db.models[name];
     model.collection.buffer = true;
   }
 };
\ No newline at end of file

From 4618fbe9c73d3dd7d2380ff6a446fbe6c05587ee Mon Sep 17 00:00:00 2001
From: aleksey-chichagov <aleksey.chichagov@akvelon.com>
Date: Wed, 8 Apr 2020 14:44:39 +0300
Subject: [PATCH 0671/2348] Fixed updatedAt field in nested documents

Changed behaviour for $set operation for update documents with multiple levels of subdocuments.
Need to run tests and validate arrays behaviour.
---
 .../update/applyTimestampsToChildren.js       | 53 +++++++++----------
 1 file changed, 26 insertions(+), 27 deletions(-)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 4ab97193680..1ab10f1d904 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -64,14 +64,13 @@ function applyTimestampsToChildren(now, update, schema) {
           continue;
         }
 
-        let parentSchemaType = null;
+        const parentSchemaTypes = [];
         const pieces = keyToSearch.split('.');
         for (let i = pieces.length - 1; i > 0; --i) {
           const s = schema.path(pieces.slice(0, i).join('.'));
           if (s != null &&
               (s.$isMongooseDocumentArray || s.$isSingleNested)) {
-            parentSchemaType = s;
-            break;
+            parentSchemaTypes.push(s);
           }
         }
 
@@ -79,32 +78,32 @@ function applyTimestampsToChildren(now, update, schema) {
           applyTimestampsToDocumentArray(update.$set[key], path, now);
         } else if (update.$set[key] && path.$isSingleNested) {
           applyTimestampsToSingleNested(update.$set[key], path, now);
-        } else if (parentSchemaType != null) {
-          timestamps = parentSchemaType.schema.options.timestamps;
-          createdAt = handleTimestampOption(timestamps, 'createdAt');
-          updatedAt = handleTimestampOption(timestamps, 'updatedAt');
-
-          if (!timestamps || updatedAt == null) {
-            continue;
-          }
-
-          if (parentSchemaType.$isSingleNested) {
-            // Single nested is easy
-            update.$set[parentSchemaType.path + '.' + updatedAt] = now;
-            continue;
-          }
+        } else if (parentSchemaTypes.length > 0) {
+          for (const parentSchemaType of parentSchemaTypes) {
+            timestamps = parentSchemaType.schema.options.timestamps;
+            createdAt = handleTimestampOption(timestamps, 'createdAt');
+            updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+
+            if (!timestamps || updatedAt == null) {
+              continue;
+            }
 
-          let childPath = key.substr(parentSchemaType.path.length + 1);
+            if (parentSchemaType.$isSingleNested) {
+              // Single nested is easy
+              update.$set[parentSchemaType.$fullPath + '.' + updatedAt] = now;
+              continue;
+            }
 
-          if (/^\d+$/.test(childPath)) {
-            update.$set[parentSchemaType.path + '.' + childPath][updatedAt] = now;
-            continue;
+            if (parentSchemaType.$isMongooseDocumentArray) {
+              const lastDot = parentSchemaType.$fullPath.lastIndexOf('.');
+              const childPath = parentSchemaType.$fullPath.substr(0, lastDot);
+              if (/^\d+$/.test(childPath)) {
+                update.$set[parentSchemaType.$fullPath + '.' + childPath][updatedAt] = now;
+              } else{
+                update.$set[parentSchemaType.$fullPath + '.' + childPath + '.' + updatedAt] = now;
+              }
+            }
           }
-
-          const firstDot = childPath.indexOf('.');
-          childPath = firstDot !== -1 ? childPath.substr(0, firstDot) : childPath;
-
-          update.$set[parentSchemaType.path + '.' + childPath + '.' + updatedAt] = now;
         } else if (path.schema != null && path.schema != schema && update.$set[key]) {
           timestamps = path.schema.options.timestamps;
           createdAt = handleTimestampOption(timestamps, 'createdAt');
@@ -177,4 +176,4 @@ function applyTimestampsToSingleNested(subdoc, schematype, now) {
   if (createdAt != null) {
     subdoc[createdAt] = now;
   }
-}
\ No newline at end of file
+}

From 220fccd23a75f7e136de114fc2506e4eae691c01 Mon Sep 17 00:00:00 2001
From: Aleksey Chichagov <aleksey.chichagov@akvelon.com>
Date: Thu, 9 Apr 2020 00:18:11 +0300
Subject: [PATCH 0672/2348] $fullPath not exists in schema. Fixed tests

---
 .../update/applyTimestampsToChildren.js       | 22 +++++++++++--------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 1ab10f1d904..4c3e820abb5 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -69,8 +69,8 @@ function applyTimestampsToChildren(now, update, schema) {
         for (let i = pieces.length - 1; i > 0; --i) {
           const s = schema.path(pieces.slice(0, i).join('.'));
           if (s != null &&
-              (s.$isMongooseDocumentArray || s.$isSingleNested)) {
-            parentSchemaTypes.push(s);
+            (s.$isMongooseDocumentArray || s.$isSingleNested)) {
+            parentSchemaTypes.push({ parentPath: key.split('.').slice(0, i).join('.'), parentSchemaType: s });
           }
         }
 
@@ -79,7 +79,7 @@ function applyTimestampsToChildren(now, update, schema) {
         } else if (update.$set[key] && path.$isSingleNested) {
           applyTimestampsToSingleNested(update.$set[key], path, now);
         } else if (parentSchemaTypes.length > 0) {
-          for (const parentSchemaType of parentSchemaTypes) {
+          for (const { parentPath, parentSchemaType } of parentSchemaTypes) {
             timestamps = parentSchemaType.schema.options.timestamps;
             createdAt = handleTimestampOption(timestamps, 'createdAt');
             updatedAt = handleTimestampOption(timestamps, 'updatedAt');
@@ -90,18 +90,22 @@ function applyTimestampsToChildren(now, update, schema) {
 
             if (parentSchemaType.$isSingleNested) {
               // Single nested is easy
-              update.$set[parentSchemaType.$fullPath + '.' + updatedAt] = now;
+              update.$set[parentPath + '.' + updatedAt] = now;
               continue;
             }
 
             if (parentSchemaType.$isMongooseDocumentArray) {
-              const lastDot = parentSchemaType.$fullPath.lastIndexOf('.');
-              const childPath = parentSchemaType.$fullPath.substr(0, lastDot);
+              let childPath = key.substr(parentPath.length + 1);
+
               if (/^\d+$/.test(childPath)) {
-                update.$set[parentSchemaType.$fullPath + '.' + childPath][updatedAt] = now;
-              } else{
-                update.$set[parentSchemaType.$fullPath + '.' + childPath + '.' + updatedAt] = now;
+                update.$set[parentPath + '.' + childPath][updatedAt] = now;
+                continue;
               }
+
+              const firstDot = childPath.indexOf('.');
+              childPath = firstDot !== -1 ? childPath.substr(0, firstDot) : childPath;
+
+              update.$set[parentPath + '.' + childPath + '.' + updatedAt] = now;
             }
           }
         } else if (path.schema != null && path.schema != schema && update.$set[key]) {

From 6fa65cbce6ba87d4adcc8bd0b940132ba15c8c36 Mon Sep 17 00:00:00 2001
From: Makinde Adeagbo <makinde@adeagbo.com>
Date: Wed, 8 Apr 2020 21:03:35 -0700
Subject: [PATCH 0673/2348] Fixing #8774

Default getter should return value when it is passed in.
---
 lib/schema.js | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 4fa8f9408ba..b9fae61250c 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1775,14 +1775,12 @@ Schema.prototype.virtual = function(name, options) {
     const virtual = this.virtual(name);
     virtual.options = options;
     return virtual.
-      get(function() {
-        if (!this.$$populatedVirtuals) {
-          this.$$populatedVirtuals = {};
-        }
-        if (this.$$populatedVirtuals.hasOwnProperty(name)) {
+      get(function(_v) {
+        if (this.$$populatedVirtuals &&
+          this.$$populatedVirtuals.hasOwnProperty(name)) {
           return this.$$populatedVirtuals[name];
         }
-        return void 0;
+        return _v;
       }).
       set(function(_v) {
         if (!this.$$populatedVirtuals) {

From 415a70f27b0bcf824ab6b87b4603b2c28b34f202 Mon Sep 17 00:00:00 2001
From: Makinde Adeagbo <makinde@adeagbo.com>
Date: Wed, 8 Apr 2020 22:45:58 -0700
Subject: [PATCH 0674/2348] Making sure null/undefined values return undefined

Also, the previous change made it so that `$$populatedVirtuals` is not added to lean objects.
---
 lib/schema.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/schema.js b/lib/schema.js
index b9fae61250c..16e5dd0de33 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1780,6 +1780,7 @@ Schema.prototype.virtual = function(name, options) {
           this.$$populatedVirtuals.hasOwnProperty(name)) {
           return this.$$populatedVirtuals[name];
         }
+        if (_v == null) return undefined;
         return _v;
       }).
       set(function(_v) {

From ab9b22fc3068f670edfe9ca63ddee39bd6b0334c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Apr 2020 18:59:21 -0400
Subject: [PATCH 0675/2348] docs(model+query+findoneandupdate): add docs for
 `returnOriginal` option

Fix #8766
---
 docs/tutorials/findoneandupdate.md        |  9 +++++++++
 lib/model.js                              | 12 ++++++++++--
 lib/query.js                              | 13 +++++++++++--
 test/es-next/findoneandupdate.test.es6.js | 17 +++++++++++++++++
 4 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/docs/tutorials/findoneandupdate.md b/docs/tutorials/findoneandupdate.md
index eac1793083f..83ab21a9c36 100644
--- a/docs/tutorials/findoneandupdate.md
+++ b/docs/tutorials/findoneandupdate.md
@@ -23,6 +23,15 @@ You should set the `new` option to `true` to return the document **after** `upda
 
 Mongoose's `findOneAndUpdate()` is slightly different from [the MongoDB Node.js driver's `findOneAndUpdate()`](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#findOneAndUpdate) because it returns the document itself, not a [result object](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~findAndModifyWriteOpResult).
 
+As an alternative to the `new` option, you can also use the `returnOriginal` option.
+`returnOriginal: false` is equivalent to `new: true`. The `returnOriginal` option
+exists for consistency with the [the MongoDB Node.js driver's `findOneAndUpdate()`](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#findOneAndUpdate),
+which has the same option.
+
+```javascript
+[require:Tutorial.*findOneAndUpdate.*returnOriginal option]
+```
+
 <h2 id="atomic-updates">Atomic Updates</h2>
 
 With the exception of an [unindexed upsert](https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/#upsert-and-unique-index), [`findOneAndUpdate()` is atomic](https://docs.mongodb.com/manual/core/write-operations-atomicity/#atomicity). That means you can assume the document doesn't change between when MongoDB finds the document and when it updates the document, _unless_ you're doing an [upsert](#upsert).
diff --git a/lib/model.js b/lib/model.js
index 4f62543ae92..bed7ba96df3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2473,11 +2473,13 @@ Model.$where = function $where() {
  * @param {Object} [conditions]
  * @param {Object} [update]
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
+ * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Function} [callback]
  * @return {Query}
  * @see Tutorial /docs/tutorials/findoneandupdate.html
@@ -2613,10 +2615,13 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Object|Number|String} id value of `_id` to query by
  * @param {Object} [update]
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and the [Mongoose lean tutorial](/docs/tutorials/lean.html).
+ * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndUpdate #model_Model.findOneAndUpdate
@@ -2808,10 +2813,13 @@ Model.findByIdAndDelete = function(id, options, callback) {
  * @param {Object} filter Replace the first document that matches this filter
  * @param {Object} [replacement] Replace with this document
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
+ * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Function} [callback]
  * @return {Query}
  * @api public
diff --git a/lib/query.js b/lib/query.js
index a5201c2efb3..a355e2b8a3d 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2941,9 +2941,13 @@ function prepareDiscriminatorCriteria(query) {
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean} [options.multipleCastError] by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.
- * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
+ * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
+ * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Function} [callback] optional params are (error, doc), _unless_ `rawResult` is used, in which case params are (error, writeOpResult)
  * @see Tutorial /docs/tutorials/findoneandupdate.html
  * @see mongodb http://www.mongodb.org/display/DOCS/findAndModify+Command
@@ -3271,8 +3275,13 @@ Query.prototype._findOneAndDelete = wrapThunk(function(callback) {
  * @param {Boolean} [options.rawResult] if true, returns the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify)
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
- * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](http://mongoosejs.com/docs/api.html#query_Query-lean).
+ * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
+ * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
+ * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
+ * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
+ * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Function} [callback] optional params are (error, document)
  * @return {Query} this
  * @api public
diff --git a/test/es-next/findoneandupdate.test.es6.js b/test/es-next/findoneandupdate.test.es6.js
index 72b4afe0243..02b5e57815f 100644
--- a/test/es-next/findoneandupdate.test.es6.js
+++ b/test/es-next/findoneandupdate.test.es6.js
@@ -79,6 +79,23 @@ describe('Tutorial: findOneAndUpdate()', function() {
     // acquit:ignore:end
   });
 
+  it('returnOriginal option', async function() {
+    const filter = { name: 'Jean-Luc Picard' };
+    const update = { age: 59 };
+
+    // `doc` is the document _after_ `update` was applied because of
+    // `returnOriginal: false`
+    let doc = await Character.findOneAndUpdate(filter, update, {
+      returnOriginal: false
+    });
+    doc.name; // 'Jean-Luc Picard'
+    doc.age; // 59
+    // acquit:ignore:start
+    assert.equal(doc.name, 'Jean-Luc Picard');
+    assert.equal(doc.age, 59);
+    // acquit:ignore:end
+  });
+
   it('save race condition', async function() {
     const filter = { name: 'Jean-Luc Picard' };
     const update = { age: 59 };

From 7c08bbe9cd2fded8b339d1d339755387ae627ad3 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Sat, 11 Apr 2020 18:05:29 +1200
Subject: [PATCH 0676/2348] docs(guide): fix English

---
 docs/3.3.x/docs/guide.jade | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/docs/3.3.x/docs/guide.jade b/docs/3.3.x/docs/guide.jade
index 6e7bb64d230..b1878f83e9d 100644
--- a/docs/3.3.x/docs/guide.jade
+++ b/docs/3.3.x/docs/guide.jade
@@ -204,7 +204,7 @@ block content
 
   h3#options Options
   :markdown
-    `Schema`s have a few configurable options which can be passed to the constructor or `set` directly:
+    `Schema`s have a few configurable options which can be passed to the constructor or the `set` method:
   :js
     new Schema({..}, options);
 
@@ -255,7 +255,7 @@ block content
 
   h4#id option: id
   :markdown
-    Mongoose assigns each of your schemas an `id` virtual getter by default which returns the documents `_id` field cast to a string, or in the case of ObjectIds, its hexString. If you don't want an `id` getter added to your schema, you may disable it passing this option at schema construction time.
+    Mongoose assigns each of your schemas an `id` virtual getter by default which returns the document's `_id` field cast to a string, or in the case of ObjectIds, its hexString. If you don't want an `id` getter added to your schema, you may disable it passing this option at schema construction time.
   :js
     // default behavior
     var schema = new Schema({ name: String });
@@ -394,7 +394,7 @@ block content
 
   h4#toJSON option: toJSON
   :markdown
-    Exactly the same as the [toObject](#toObject) option but only applies when the documents `toJSON` method is called.
+    Exactly the same as the [toObject](#toObject) option but only applies when the document's `toJSON` method is called.
   :js
     var schema = new Schema({ name: String });
     schema.path('name').get(function (v) {
@@ -410,7 +410,7 @@ block content
 
   h4#toObject option: toObject
   :markdown
-    Documents have a [toObject](/docs/api.html#document_Document-toObject) method which converts the mongoose document into a plain javascript object. This method accepts a few options. Instead of applying these options on a per-document basis we may declare the options here and have it applied to all of this schemas documents by default.
+    Documents have a [toObject](/docs/api.html#document_Document-toObject) method which converts the mongoose document into a plain JavaScript object. This method accepts a few options. Instead of applying these options on a per-document basis, we may declare the options at the schena level, and have them applied to all of the schema's documents by default.
 
     To have all virtuals show up in your `console.log` output, set the `toObject` option to `{ getters: true }`:
 
@@ -426,7 +426,7 @@ block content
 
   h4#versionKey option: versionKey
   :markdown
-    The `versionKey` is a property set on each document when first created by Mongoose. This keys value contains the internal [revision](http://aaronheckmann.posterous.com/mongoose-v3-part-1-versioning) of the document. The name of this document property is configurable. The default is `__v`. If this conflicts with your application you can configure as such:
+    The `versionKey` is a property set on each document when first created by Mongoose. This key's value contains the internal [revision](http://aaronheckmann.posterous.com/mongoose-v3-part-1-versioning) of the document. The name of this document property is configurable. The default is `__v`. If this conflicts with your application you can configure as such:
   :js
     var schema = new Schema({ name: 'string' });
     var Thing = db.model('Thing', schema);

From 10a6c3569e4fb2222a26dcfc4cac687fd146c9bc Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Sat, 11 Apr 2020 18:20:59 +1200
Subject: [PATCH 0677/2348] docs(guide): fix English

---
 docs/guide.pug | 31 ++++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index a9edadd4fa1..706700277e7 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -187,7 +187,7 @@ block content
 
     <h3 id="statics"><a href="#statics">Statics</a></h3>
 
-    You can also add static functions to your model. There are 2 equivalent
+    You can also add static functions to your model. There are two equivalent
     ways to add a static:
 
     - Add a function property to `schema.statics`
@@ -396,7 +396,7 @@ block content
     <h3 id="options"><a href="#options">Options</a></h3>
 
     Schemas have a few configurable options which can be passed to the
-    constructor or `set` directly:
+    constructor or to the `set` method:
 
     ```javascript
     new Schema({..}, options);
@@ -530,9 +530,9 @@ block content
     <h3 id="id"><a href="#id">option: id</a></h3>
 
     Mongoose assigns each of your schemas an `id` virtual getter by default
-    which returns the documents `_id` field cast to a string, or in the case of
+    which returns the document's `_id` field cast to a string, or in the case of
     ObjectIds, its hexString. If you don't want an `id` getter added to your
-    schema, you may disable it passing this option at schema construction time.
+    schema, you may disable it by passing this option at schema construction time.
 
     ```javascript
     // default behavior
@@ -728,7 +728,8 @@ block content
     The `strict` option may also be set to `"throw"` which will cause errors
     to be produced instead of dropping the bad data.
 
-    _NOTE: Any key/val set on the instance that does not exist in your schema is always ignored, regardless of schema option._
+    _NOTE: Any key/val set on the instance that does not exist in your schema
+    is always ignored, regardless of schema option._
 
     ```javascript
     var thingSchema = new Schema({..})
@@ -776,7 +777,7 @@ block content
     <h3 id="toJSON"><a href="#toJSON">option: toJSON</a></h3>
 
     Exactly the same as the [toObject](#toObject) option but only applies when
-    the documents `toJSON` method is called.
+    the document's `toJSON` method is called.
 
     ```javascript
     var schema = new Schema({ name: String });
@@ -797,10 +798,10 @@ block content
     <h3 id="toObject"><a href="#toObject">option: toObject</a></h3>
 
     Documents have a [toObject](/docs/api.html#document_Document-toObject) method
-    which converts the mongoose document into a plain javascript object. This
+    which converts the mongoose document into a plain JavaScript object. This
     method accepts a few options. Instead of applying these options on a
-    per-document basis we may declare the options here and have it applied to
-    all of this schemas documents by default.
+    per-document basis, we may declare the options at the schema level and have
+    them applied to all of the schema's documents by default.
 
     To have all virtuals show up in your `console.log` output, set the
     `toObject` option to `{ getters: true }`:
@@ -976,11 +977,11 @@ block content
 
     <h3 id="timestamps"><a href="#timestamps">option: timestamps</a></h3>
 
-    If set `timestamps`, mongoose assigns `createdAt` and `updatedAt` fields to
-    your schema, the type assigned is [Date](./api.html#schema-date-js).
+    The `timestamps` option tells mongoose to assign `createdAt` and `updatedAt` fields
+    to your schema. The type assigned is [Date](./api.html#schema-date-js).
 
-    By default, the name of two fields are `createdAt` and `updatedAt`, customize
-    the field name by setting `timestamps.createdAt` and `timestamps.updatedAt`.
+    By default, the names of the fields are `createdAt` and `updatedAt`. Customize
+    the field names by setting `timestamps.createdAt` and `timestamps.updatedAt`.
 
     ```javascript
     const thingSchema = new Schema({..}, { timestamps: { createdAt: 'created_at' } });
@@ -1016,8 +1017,8 @@ block content
     ]);
     ```
 
-    By default, Mongoose uses the current time `new Date()` to get
-    the current time. But if you want to overwrite the function
+    By default, Mongoose uses `new Date()` to get the current time.
+    If you want to overwrite the function
     Mongoose uses to get the current time, you can set the
     `timestamps.currentTime` option. Mongoose will call the
     `timestamps.currentTime` function whenever it needs to get

From 4d871c7b135c582b605e9a124e15952d52b9452a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Apr 2020 18:53:07 +0200
Subject: [PATCH 0678/2348] test: repro #8778

---
 test/model.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 400538bef86..b1a923c5a73 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6563,4 +6563,30 @@ describe('Model', function() {
       assert.deepEqual(users[1].updatedAt, usersAfterUpdate[1].updatedAt);
     });
   });
+
+  it('bulkWrite can overwrite schema `strict` option (gh-8778)', function() {
+    const userSchema = new Schema({
+      name: String
+    }, { strict: true });
+
+    const User = db.model('User', userSchema);
+
+    return co(function*() {
+      const users = yield User.create([{ name: 'Hafez1' }, { name: 'Hafez2' }]);
+
+      yield User.bulkWrite([
+        { updateOne: { filter: { _id: users[0]._id }, update: { notInSchema: 1 } } },
+        { updateMany: { filter: { _id: users[1]._id }, update: { notInSchema: 2 } } }
+      ],
+      { strict: false });
+
+      const usersAfterUpdate = yield Promise.all([
+        User.collection.findOne({ _id: users[0]._id }),
+        User.collection.findOne({ _id: users[1]._id })
+      ]);
+
+      assert.equal(usersAfterUpdate[0].notInSchema, 1);
+      assert.equal(usersAfterUpdate[1].notInSchema, 2);
+    });
+  });
 });

From b592c870d0a0d340b9e812b861aaf9c14114a483 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Apr 2020 18:53:34 +0200
Subject: [PATCH 0679/2348] make builkWrite `strict` overwrite schema `strict`

---
 lib/helpers/model/castBulkWrite.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 15b7e5dff4c..34b7be715d4 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -40,11 +40,11 @@ module.exports = function castBulkWrite(model, op, options) {
 
         _addDiscriminatorToObject(schema, op['updateOne']['filter']);
         op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter'], {
-          strict: model.schema.options.strict,
+          strict: options.strict != null ? options.strict : model.schema.options.strict,
           upsert: op['updateOne'].upsert
         });
         op['updateOne']['update'] = castUpdate(model.schema, op['updateOne']['update'], {
-          strict: model.schema.options.strict,
+          strict: options.strict != null ? options.strict : model.schema.options.strict,
           overwrite: false
         });
 
@@ -74,11 +74,11 @@ module.exports = function castBulkWrite(model, op, options) {
 
         _addDiscriminatorToObject(schema, op['updateMany']['filter']);
         op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter'], {
-          strict: model.schema.options.strict,
+          strict: options.strict != null ? options.strict : model.schema.options.strict,
           upsert: op['updateMany'].upsert
         });
         op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
-          strict: model.schema.options.strict,
+          strict: options.strict != null ? options.strict : model.schema.options.strict,
           overwrite: false
         });
         if (op['updateMany'].setDefaultsOnInsert) {
@@ -104,7 +104,7 @@ module.exports = function castBulkWrite(model, op, options) {
       _addDiscriminatorToObject(schema, op['replaceOne']['filter']);
       try {
         op['replaceOne']['filter'] = cast(model.schema, op['replaceOne']['filter'], {
-          strict: model.schema.options.strict,
+          strict: options.strict != null ? options.strict : model.schema.options.strict,
           upsert: op['replaceOne'].upsert
         });
       } catch (error) {

From 93f1d49c766468f221e81c24520ab4d76957a7a1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Apr 2020 19:36:58 +0200
Subject: [PATCH 0680/2348] Make bulkWrite replaceOne respect `strict` option

---
 lib/helpers/model/castBulkWrite.js | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 34b7be715d4..a681049dacb 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -14,6 +14,7 @@ const setDefaultsOnInsert = require('../setDefaultsOnInsert');
 module.exports = function castBulkWrite(model, op, options) {
   const now = model.base.now();
   const schema = model.schema;
+  const strict = options.strict != null ? options.strict : model.schema.options.strict;
 
   if (op['insertOne']) {
     return (callback) => {
@@ -40,11 +41,11 @@ module.exports = function castBulkWrite(model, op, options) {
 
         _addDiscriminatorToObject(schema, op['updateOne']['filter']);
         op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter'], {
-          strict: options.strict != null ? options.strict : model.schema.options.strict,
+          strict: strict,
           upsert: op['updateOne'].upsert
         });
         op['updateOne']['update'] = castUpdate(model.schema, op['updateOne']['update'], {
-          strict: options.strict != null ? options.strict : model.schema.options.strict,
+          strict: strict,
           overwrite: false
         });
 
@@ -74,11 +75,11 @@ module.exports = function castBulkWrite(model, op, options) {
 
         _addDiscriminatorToObject(schema, op['updateMany']['filter']);
         op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter'], {
-          strict: options.strict != null ? options.strict : model.schema.options.strict,
+          strict: strict,
           upsert: op['updateMany'].upsert
         });
         op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
-          strict: options.strict != null ? options.strict : model.schema.options.strict,
+          strict: strict,
           overwrite: false
         });
         if (op['updateMany'].setDefaultsOnInsert) {
@@ -104,7 +105,7 @@ module.exports = function castBulkWrite(model, op, options) {
       _addDiscriminatorToObject(schema, op['replaceOne']['filter']);
       try {
         op['replaceOne']['filter'] = cast(model.schema, op['replaceOne']['filter'], {
-          strict: options.strict != null ? options.strict : model.schema.options.strict,
+          strict: strict,
           upsert: op['replaceOne'].upsert
         });
       } catch (error) {
@@ -112,7 +113,7 @@ module.exports = function castBulkWrite(model, op, options) {
       }
 
       // set `skipId`, otherwise we get "_id field cannot be changed"
-      const doc = new model(op['replaceOne']['replacement'], null, true);
+      const doc = new model(op['replaceOne']['replacement'], strict, true);
       if (model.schema.options.timestamps != null) {
         doc.initializeTimestamps();
       }

From e24389c1511debfaa0d040d7d956dab1b584e50b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Apr 2020 19:37:37 +0200
Subject: [PATCH 0681/2348] Assert on filters, and update/replacement

---
 test/model.test.js | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index b1a923c5a73..4f31b4d2891 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6564,7 +6564,8 @@ describe('Model', function() {
     });
   });
 
-  it('bulkWrite can overwrite schema `strict` option (gh-8778)', function() {
+  it('bulkWrite can overwrite schema `strict` option for filters and updates (gh-8778)', function() {
+    // Arrange
     const userSchema = new Schema({
       name: String
     }, { strict: true });
@@ -6572,21 +6573,31 @@ describe('Model', function() {
     const User = db.model('User', userSchema);
 
     return co(function*() {
-      const users = yield User.create([{ name: 'Hafez1' }, { name: 'Hafez2' }]);
+      const users = yield User.collection.insertMany([
+        { notInSchema: 1 },
+        { notInSchema: 2 },
+        { notInSchema: 3 }
+      ], { strict: false }).then(res=>res.ops);
 
+      // Act
       yield User.bulkWrite([
-        { updateOne: { filter: { _id: users[0]._id }, update: { notInSchema: 1 } } },
-        { updateMany: { filter: { _id: users[1]._id }, update: { notInSchema: 2 } } }
+        { updateOne: { filter: { notInSchema: 1 }, update: { notInSchema: 'first' } } },
+        { updateMany: { filter: { notInSchema: 2 }, update: { notInSchema: 'second' } } },
+        { replaceOne: { filter: { notInSchema: 3 }, replacement: { notInSchema: 'third' } } }
       ],
       { strict: false });
 
+      // Assert
       const usersAfterUpdate = yield Promise.all([
         User.collection.findOne({ _id: users[0]._id }),
-        User.collection.findOne({ _id: users[1]._id })
+        User.collection.findOne({ _id: users[1]._id }),
+        User.collection.findOne({ _id: users[2]._id })
       ]);
 
-      assert.equal(usersAfterUpdate[0].notInSchema, 1);
-      assert.equal(usersAfterUpdate[1].notInSchema, 2);
+      assert.equal(usersAfterUpdate[0].notInSchema, 'first');
+      assert.equal(usersAfterUpdate[1].notInSchema, 'second');
+      assert.equal(usersAfterUpdate[2].notInSchema, 'third');
     });
   });
+
 });

From 5f9f10abee8a96cbece37343badaaedbd2bfb006 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Apr 2020 19:46:23 +0200
Subject: [PATCH 0682/2348] docs: add options.strict to Model#bulkWrite

---
 lib/model.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/model.js b/lib/model.js
index bed7ba96df3..d1c1e07c05c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3481,6 +3481,7 @@ function _setIsNew(doc, val) {
  * @param {number} [options.wtimeout=null] The [write concern timeout](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout).
  * @param {Boolean} [options.j=true] If false, disable [journal acknowledgement](https://docs.mongodb.com/manual/reference/write-concern/#j-option)
  * @param {Boolean} [options.bypassDocumentValidation=false] If true, disable [MongoDB server-side schema validation](https://docs.mongodb.com/manual/core/schema-validation/) for all writes in this bulk.
+ * @param {Boolean} [options.strict=null] If true, overwrites the [`strict` option](/docs/guide.html#strict) on schema, and allows filtering and writing fields not defined in the schema for all writes in this bulk.
  * @param {Function} [callback] callback `function(error, bulkWriteOpResult) {}`
  * @return {Promise} resolves to a [`BulkWriteOpResult`](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult) if the operation succeeds
  * @api public

From 9ae6db0fba948fa88a99cec79ea44d6c8c6fed28 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 11 Apr 2020 19:52:52 +0200
Subject: [PATCH 0683/2348] docs: improve options.strict description

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index d1c1e07c05c..2a07eb8526e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3481,7 +3481,7 @@ function _setIsNew(doc, val) {
  * @param {number} [options.wtimeout=null] The [write concern timeout](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout).
  * @param {Boolean} [options.j=true] If false, disable [journal acknowledgement](https://docs.mongodb.com/manual/reference/write-concern/#j-option)
  * @param {Boolean} [options.bypassDocumentValidation=false] If true, disable [MongoDB server-side schema validation](https://docs.mongodb.com/manual/core/schema-validation/) for all writes in this bulk.
- * @param {Boolean} [options.strict=null] If true, overwrites the [`strict` option](/docs/guide.html#strict) on schema, and allows filtering and writing fields not defined in the schema for all writes in this bulk.
+ * @param {Boolean} [options.strict=null] Overwrites the [`strict` option](/docs/guide.html#strict) on schema. If false, allows filtering and writing fields not defined in the schema for all writes in this bulk.
  * @param {Function} [callback] callback `function(error, bulkWriteOpResult) {}`
  * @return {Promise} resolves to a [`BulkWriteOpResult`](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult) if the operation succeeds
  * @api public

From 78f42987f5de5dd5c34730bd1dc31a0d9c6c7222 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Apr 2020 15:44:32 -0400
Subject: [PATCH 0684/2348] fix(document): handle validating document array
 whose docs contain maps and nested paths

Fix #8767
---
 lib/helpers/document/compile.js | 12 +++++++++++-
 test/types.map.test.js          | 29 +++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index ecc4f6f97e1..f6eb160adee 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -163,7 +163,17 @@ function getOwnPropertyDescriptors(object) {
       delete result[key];
       return;
     }
-    result[key].enumerable = ['isNew', '$__', 'errors', '_doc', '$locals', '$op'].indexOf(key) === -1;
+    result[key].enumerable = [
+      'isNew',
+      '$__',
+      'errors',
+      '_doc',
+      '$locals',
+      '$op',
+      '__parentArray',
+      '__index',
+      '$isDocumentArrayElement'
+    ].indexOf(key) === -1;
   });
 
   return result;
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 4d1876a0ab6..4ce5895b600 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -869,4 +869,33 @@ describe('Map', function() {
     assert.equal(doc.books.get('casino-royale'), 'Casino Royale, by Ian Fleming');
     assert.equal(doc.get('books.casino-royale'), 'Casino Royale, by Ian Fleming');
   });
+
+  it('handles validation of document array with maps and nested paths (gh-8767)', function() {
+    const subSchema = Schema({
+      _id: Number,
+      level2: {
+        type : Map,
+        of: Schema({
+          _id: Number,
+          level3: { 
+            type: Map,
+            of: Number,
+            required: true
+          }
+        })
+      },
+      otherProps: { test: Number }
+    });
+    const mainSchema = Schema({ _id: Number, level1: [subSchema] });
+    const Test = db.model('Test', mainSchema);
+
+    const doc = new Test({
+      _id: 1,
+      level1: [
+        { _id: 10, level2: { answer: { _id: 101, level3: { value: 42 } } } },
+        { _id: 20, level2: { powerLevel: { _id: 201, level3: { value: 9001 } } } }
+      ]
+    });
+    return doc.validate();
+  });
 });

From 5a1cec5a0eb3553a37f8e3e055d99f8a26c7e116 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Apr 2020 15:54:49 -0400
Subject: [PATCH 0685/2348] test(document): repro #8765

---
 test/document.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index b90ce98c847..4e573e705cf 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -7886,6 +7886,32 @@ describe('document', function() {
         });
       });
     });
+
+    it('skips discriminator key', function() {
+      return co(function*() {
+        const D = Model.discriminator('D', Schema({ other: String }));
+        yield Model.collection.insertOne({
+          _id: 2,
+          __v: 5,
+          __t: 'D',
+          name: 'test',
+          nested: { prop: 'foo' },
+          immutable: 'bar',
+          other: 'baz'
+        });
+        const doc = yield D.findOne({ _id: 2 });
+        doc.overwrite({ _id: 2, name: 'test2' });
+
+        assert.deepEqual(doc.toObject(), {
+          _id: 2,
+          __v: 5,
+          __t: 'D',
+          name: 'test2',
+          immutable: 'bar'
+        });
+        return doc.validate();
+      });
+    });
   });
 
   it('copies virtuals from array subdocs when casting array of docs with same schema (gh-7898)', function() {

From 7dc8a0a9f69e3836781599180d22862a3ad1a7bd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Apr 2020 16:10:12 -0400
Subject: [PATCH 0686/2348] style: fix lint

---
 test/types.map.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index 4ce5895b600..aa50f7266a8 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -874,10 +874,10 @@ describe('Map', function() {
     const subSchema = Schema({
       _id: Number,
       level2: {
-        type : Map,
+        type: Map,
         of: Schema({
           _id: Number,
-          level3: { 
+          level3: {
             type: Map,
             of: Number,
             required: true

From c95a2f1a0b14c891afc69b9e67b95550779398d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Apr 2020 16:10:23 -0400
Subject: [PATCH 0687/2348] fix(document): skip discriminator key when
 overwriting a document

Fix #8765
---
 lib/document.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 269bfc9d55e..c758e4ce3db 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -833,6 +833,9 @@ Document.prototype.overwrite = function overwrite(obj) {
     if (this.schema.options.versionKey && key === this.schema.options.versionKey) {
       continue;
     }
+    if (this.schema.options.discriminatorKey && key === this.schema.options.discriminatorKey) {
+      continue;
+    }
     this.$set(key, obj[key]);
   }
 

From b107d902fbb57a36855a08f4bc5dcb956efe5bf3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Apr 2020 17:02:57 -0400
Subject: [PATCH 0688/2348] fix(populate): support `clone` option with `lean`

Fix #8761
Fix #8760
---
 .../populate/assignRawDocsToIdStructure.js    | 10 +++-
 test/model.populate.test.js                   | 51 +++++++++++++++++++
 2 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignRawDocsToIdStructure.js b/lib/helpers/populate/assignRawDocsToIdStructure.js
index b84f7131ca2..d46f87df65d 100644
--- a/lib/helpers/populate/assignRawDocsToIdStructure.js
+++ b/lib/helpers/populate/assignRawDocsToIdStructure.js
@@ -1,6 +1,8 @@
 'use strict';
 
+const leanPopulateMap = require('./leanPopulateMap');
 const modelSymbol = require('../symbols').modelSymbol;
+const utils = require('../../utils');
 
 module.exports = assignRawDocsToIdStructure;
 
@@ -55,7 +57,13 @@ function assignRawDocsToIdStructure(rawIds, resultDocs, resultOrder, options, re
     doc = resultDocs[sid];
     // If user wants separate copies of same doc, use this option
     if (options.clone) {
-      doc = doc.constructor.hydrate(doc._doc);
+      if (options.lean) {
+        const _model = leanPopulateMap.get(doc);
+        doc = utils.clone(doc);
+        leanPopulateMap.set(doc, _model);
+      } else {
+        doc = doc.constructor.hydrate(doc._doc);
+      }
     }
 
     if (recursed) {
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a3c203af156..03f1d12ceaa 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9273,4 +9273,55 @@ describe('model: populate:', function() {
       assert.ok(doc.items[0].populated('child'));
     });
   });
+
+  describe('gh-8760', function() {
+    it('clone with lean creates identical copies from the same document', function() {
+      const userSchema = new Schema({ name: String });
+      const User = db.model('User', userSchema);
+
+      const postSchema = new Schema({
+        user: { type: mongoose.ObjectId, ref: 'User' },
+        title: String
+      });
+
+      const Post = db.model('BlogPost', postSchema);
+
+      return co(function*() {
+        const user = yield User.create({ name: 'val' });
+        yield Post.create([
+          { title: 'test1', user: user },
+          { title: 'test2', user: user }
+        ]);
+
+        const posts = yield Post.find().populate({ path: 'user', options: { clone: true } }).lean();
+
+        posts[0].user.name = 'val2';
+        assert.equal(posts[1].user.name, 'val');
+      });
+    });
+
+    it('clone with populate and lean makes child lean', function() { {
+      const isLean = v => v != null && !(v instanceof mongoose.Document);
+
+      const userSchema = new Schema({ name: String });
+      const User = db.model('User', userSchema);
+
+      const postSchema = new Schema({
+        user: { type: mongoose.ObjectId, ref: 'User' },
+        title: String
+      });
+
+      const Post = db.model('BlogPost', postSchema);
+
+      return co(function*() {
+        const user = yield User.create({ name: 'val' });
+
+        yield Post.create({ title: 'test1', user: user });
+
+        const post = yield Post.findOne().populate({ path: 'user', options: { clone: true } }).lean();
+
+        assert.ok(isLean(post.user));
+      });
+    }});
+  });
 });
\ No newline at end of file

From 95351e7b1ade3294e76d7c4e3f8be37a1b0f1301 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 12 Apr 2020 12:33:40 -0400
Subject: [PATCH 0689/2348] docs(queries): expand streaming section to include
 async iterators, cursor timeouts, and sesssion idle timeouts

Fix #8720
---
 docs/queries.pug | 35 ++++++++++++++++++++++++++++-------
 1 file changed, 28 insertions(+), 7 deletions(-)

diff --git a/docs/queries.pug b/docs/queries.pug
index faa4d68184c..f17bb68b6a2 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -167,15 +167,36 @@ block content
     [QueryCursor](./api.html#query_Query-cursor).
 
     ```javascript
-    var cursor = Person.find({ occupation: /host/ }).cursor();
-    cursor.on('data', function(doc) {
-      // Called once for every document
-    });
-    cursor.on('close', function() {
-      // Called when done
-    });
+    const cursor = Person.find({ occupation: /host/ }).cursor();
+
+    for (let doc = await cursor.next(); doc != null; doc = await cursor.next()) {
+      console.log(doc); // Prints documents one at a time
+    }
+    ```
+
+    Iterating through a Mongoose query using [async iterators](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js.html)
+    also creates a cursor.
+
+    ```javascript
+    for await (const doc of Person.find()) {
+      console.log(doc); // Prints documents one at a time
+    }
+    ```
+
+    Cursors are subject to [cursor timeouts](https://stackoverflow.com/questions/21853178/when-a-mongodb-cursor-will-expire).
+    By default, MongoDB will close your cursor after 10 minutes and subsequent
+    `next()` calls will result in a `MongoError: cursor id 123 not found` error.
+    To override this, set the `noCursorTimeout` option on your cursor.
+
+    ```javascript
+    // MongoDB won't automatically close this cursor after 10 minutes.
+    const cursor = Person.find().cursor().addCursorFlag('noCursorTimeout', true);
     ```
 
+    However, cursors can still time out because of [session idle timeouts](https://docs.mongodb.com/manual/reference/method/cursor.noCursorTimeout/#session-idle-timeout-overrides-nocursortimeout).
+    So even a cursor with `noCursorTimeout` set will still time out after 30 minutes
+    of inactivity. You can read more about working around session idle timeouts in the [MongoDB documentation](https://docs.mongodb.com/manual/reference/method/cursor.noCursorTimeout/#session-idle-timeout-overrides-nocursortimeout).
+
     <h3 id="versus-aggregation"><a href="#versus-aggregation">Versus Aggregation</a></h3>
 
     [Aggregation](https://mongoosejs.com/docs/api.html#aggregate_Aggregate) can

From b7434986fe6d2729b8635744b7d66c2f10d5740a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 12 Apr 2020 12:52:53 -0400
Subject: [PATCH 0690/2348] test(transactions): use `endSession()` in all
 transactions examples

Fix #8741
---
 test/docs/transactions.test.js | 55 +++++++++++++++++++---------------
 1 file changed, 31 insertions(+), 24 deletions(-)

diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index 95e0aa4f589..e27662861d8 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -76,22 +76,29 @@ describe('transactions', function() {
       // visible outside of the transaction.
       then(() => session.commitTransaction()).
       then(() => Customer.findOne({ name: 'Test' })).
-      then(doc => assert.ok(doc));
+      then(doc => assert.ok(doc)).
+      then(() => session.endSession());
   });
 
   it('withTransaction', function() {
     // acquit:ignore:start
     const Customer = db.model('Customer_withTrans', new Schema({ name: String }));
     // acquit:ignore:end
+
+    let session = null;
     return Customer.createCollection().
       then(() => Customer.startSession()).
       // The `withTransaction()` function's first parameter is a function
       // that returns a promise.
-      then(session => session.withTransaction(() => {
-        return Customer.create([{ name: 'Test' }], { session: session });
-      })).
+      then(_session => {
+        session = _session;
+        return session.withTransaction(() => {
+          return Customer.create([{ name: 'Test' }], { session: session });
+        });
+      }).
       then(() => Customer.countDocuments()).
-      then(count => assert.strictEqual(count, 1));
+      then(count => assert.strictEqual(count, 1)).
+      then(() => session.endSession());
   });
 
   it('abort', function() {
@@ -109,7 +116,8 @@ describe('transactions', function() {
       then(() => Customer.create([{ name: 'Test2' }], { session: session })).
       then(() => session.abortTransaction()).
       then(() => Customer.countDocuments()).
-      then(count => assert.strictEqual(count, 0));
+      then(count => assert.strictEqual(count, 0)).
+      then(() => session.endSession());
   });
 
   it('save', function() {
@@ -136,10 +144,9 @@ describe('transactions', function() {
       then(() => User.findOne({ name: 'bar' })).
       // Won't find the doc because `save()` is part of an uncommitted transaction
       then(doc => assert.ok(!doc)).
-      then(() => {
-        session.commitTransaction();
-        return User.findOne({ name: 'bar' });
-      }).
+      then(() => session.commitTransaction()).
+      then(() => session.endSession()).
+      then(() => User.findOne({ name: 'bar' })).
       then(doc => assert.ok(doc));
   });
 
@@ -195,14 +202,13 @@ describe('transactions', function() {
         },
         { $sort: { count: -1, '_id.year': -1, '_id.month': -1 } }
       ]).session(session)).
-      then(res => {
-        assert.deepEqual(res, [
-          { _id: { month: 6, year: 2018 }, count: 2 },
-          { _id: { month: 6, year: 2017 }, count: 1 },
-          { _id: { month: 5, year: 2017 }, count: 1 }
-        ]);
-        session.commitTransaction();
-      });
+      then(res => assert.deepEqual(res, [
+        { _id: { month: 6, year: 2018 }, count: 2 },
+        { _id: { month: 6, year: 2017 }, count: 1 },
+        { _id: { month: 5, year: 2017 }, count: 1 }
+      ])).
+      then(() => session.commitTransaction()).
+      then(() => session.endSession());
   });
 
   describe('populate (gh-6754)', function() {
@@ -238,9 +244,9 @@ describe('transactions', function() {
         });
     });
 
-    afterEach(function(done) {
+    afterEach(function() {
       session.commitTransaction();
-      done();
+      return session.endSession();
     });
 
     it('`populate()` uses the querys session', function() {
@@ -311,10 +317,9 @@ describe('transactions', function() {
       then(() => Character.deleteMany({ name: /Lannister/ }, { session: session })).
       then(() => Character.deleteOne({ name: 'Jon Snow' }, { session: session })).
       then(() => Character.find({}).session(session)).
-      then(res => {
-        assert.equal(res.length, 1);
-        session.commitTransaction();
-      });
+      then(res => assert.equal(res.length, 1)).
+      then(() => session.commitTransaction()).
+      then(() => session.endSession());
   });
 
   it('remove, update, updateOne (gh-7455)', function() {
@@ -337,6 +342,7 @@ describe('transactions', function() {
 
       // Undo both update and delete since doc should pull from `$session()`
       yield session.abortTransaction();
+      session.endSession();
 
       const fromDb = yield Character.findOne().then(doc => doc.toObject());
       delete fromDb._id;
@@ -354,6 +360,7 @@ describe('transactions', function() {
         const test = yield Test.create([{}], { session }).then(res => res[0]);
         yield test.save(); // throws DocumentNotFoundError
       }));
+      yield session.endSession();
     });
   });
 });

From 9bb0274c580ef2a8f0603b90ea865c1f0d2f8e0f Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Mon, 13 Apr 2020 17:19:59 +1200
Subject: [PATCH 0691/2348] docs(lib/model): fix punctuation

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 2a07eb8526e..8b42f49f546 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3404,13 +3404,13 @@ function _setIsNew(doc, val) {
 /**
  * Sends multiple `insertOne`, `updateOne`, `updateMany`, `replaceOne`,
  * `deleteOne`, and/or `deleteMany` operations to the MongoDB server in one
- * command. This is faster than sending multiple independent operations (like)
+ * command. This is faster than sending multiple independent operations (e.g.
  * if you use `create()`) because with `bulkWrite()` there is only one round
  * trip to MongoDB.
  *
  * Mongoose will perform casting on all operations you provide.
  *
- * This function does **not** trigger any middleware, not `save()` nor `update()`.
+ * This function does **not** trigger any middleware, neither `save()`, nor `update()`.
  * If you need to trigger
  * `save()` middleware for every document use [`create()`](http://mongoosejs.com/docs/api.html#model_Model.create) instead.
  *

From 89a70e8a7a3ab3efb484dba955cbd4356adc92e3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 13 Apr 2020 10:08:03 -0400
Subject: [PATCH 0692/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index ce3fb6677e2..30c6f2088d0 100644
--- a/index.pug
+++ b/index.pug
@@ -307,6 +307,9 @@ html(lang='en')
               <a href="https://www.casinot.net/">
                 <img class="sponsor" src="https://images.opencollective.com/casinot-net/242597a/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://420couponcodes.com/">
+                <img class="sponsor" src="https://images.opencollective.com/420couponcodes/8965926/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From b30213869c3e2c48bc3daa24b3eb28b8b36718d6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 13 Apr 2020 10:31:26 -0400
Subject: [PATCH 0693/2348] chore: release 5.9.9

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 2831a6f7d6a..db4f4fd973b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.9.9 / 2020-04-13
+==================
+ * fix(model): make Model.bulkWrite accept `strict` option #8782 #8788 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(virtual): make populated virtual getter return value when it is passed in #8775 #8774 [makinde](https://github.com/makinde)
+ * fix(document): handle validating document array whose docs contain maps and nested paths #8767
+ * fix(document): skip discriminator key when overwriting a document #8765
+ * fix(populate): support `clone` option with `lean` #8761 #8760
+ * docs(transactions): use `endSession()` in all transactions examples #8741
+ * docs(queries): expand streaming section to include async iterators, cursor timeouts, and sesssion idle timeouts #8720
+ * docs(model+query+findoneandupdate): add docs for `returnOriginal` option #8766
+ * docs(model): fix punctuation #8788 [dandv](https://github.com/dandv)
+ * docs: fix typos #8780 #8799 [dandv](https://github.com/dandv)
+
 5.9.8 / 2020-04-06
 ==================
  * fix(map): run getters when calling `Map#get()` #8730
diff --git a/package.json b/package.json
index f2170ad6769..84a2e1a7a2f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.8",
+  "version": "5.9.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From f16237c8dc43202caa90c9b3c2edd6b7c2aac287 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 13 Apr 2020 18:45:56 +0200
Subject: [PATCH 0694/2348] docs: add skipId to model documentation page

---
 lib/model.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/model.js b/lib/model.js
index 8b42f49f546..e1efddacfd6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -87,6 +87,7 @@ const saveToObjectOptions = Object.assign({}, internalToObjectOptions, {
  *
  * @param {Object} doc values for initial set
  * @param [fields] optional object containing the fields that were selected in the query which returned this document. You do **not** need to set this parameter to ensure Mongoose handles your [query projection](./api.html#query_Query-select).
+ * @param {Boolean} [skipId=false] optional boolean. If true, mongoose doesn't add an `_id` field to the document.
  * @inherits Document http://mongoosejs.com/docs/api.html#document-js
  * @event `error`: If listening to this event, 'error' is emitted when a document was saved without passing a callback and an `error` occurred. If not listening, the event bubbles to the connection used to create this Model.
  * @event `index`: Emitted after `Model#ensureIndexes` completes. If an error occurred it is passed with the event.

From d3952de95bd151df83580a213e6ab03a8d69c0cf Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Tue, 14 Apr 2020 17:27:13 +1200
Subject: [PATCH 0695/2348] docs(queries): rm extra word

---
 docs/queries.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/queries.pug b/docs/queries.pug
index f17bb68b6a2..ceaa5010d7c 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -69,7 +69,7 @@ block content
     });
     ```
 
-    Mongoose executed the query and passed the results passed to `callback`. All callbacks in Mongoose use the pattern:
+    Mongoose executed the query and passed the results to `callback`. All callbacks in Mongoose use the pattern:
     `callback(error, result)`. If an error occurs executing the query, the `error` parameter will contain an error document, and `result`
     will be null. If the query is successful, the `error` parameter will be null, and the `result` will be populated with the results of the query.
 

From 482300a261c1209f88a7f840e4c17b48d9b9b684 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Tue, 14 Apr 2020 17:57:00 +1200
Subject: [PATCH 0696/2348] docs(populate): typo fix

---
 docs/populate.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index de1383a28b0..9c7e49c0205 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -20,7 +20,7 @@ block content
 
     MongoDB has the join-like [$lookup](https://docs.mongodb.com/manual/reference/operator/aggregation/lookup/) aggregation operator in versions >= 3.2. Mongoose has a more powerful alternative called `populate()`, which lets you reference documents in other collections.
 
-    Population is the process of automatically replacing the specified paths in the document with document(s) from other collection(s). We may populate a single document, multiple documents, plain object, multiple plain objects, or all objects returned from a query. Let's look at some examples.
+    Population is the process of automatically replacing the specified paths in the document with document(s) from other collection(s). We may populate a single document, multiple documents, a plain object, multiple plain objects, or all objects returned from a query. Let's look at some examples.
 
     ```javascript
     const mongoose = require('mongoose');

From be9f6d9046351c2f73ed2961b3cd7812e31b34e2 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Tue, 14 Apr 2020 17:58:39 +1200
Subject: [PATCH 0697/2348] docs(populate): typo fix

---
 docs/populate.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 9c7e49c0205..152d1909c32 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -95,7 +95,7 @@ block content
 
       story1.save(function (err) {
         if (err) return handleError(err);
-        // thats it!
+        // that's it!
       });
     });
     ```

From 28874b3fd915f63d4933e66e2e2f77aba3dcbb05 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 14 Apr 2020 12:01:21 -0400
Subject: [PATCH 0698/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 30c6f2088d0..7258fd6a6f3 100644
--- a/index.pug
+++ b/index.pug
@@ -310,6 +310,9 @@ html(lang='en')
               <a href="https://420couponcodes.com/">
                 <img class="sponsor" src="https://images.opencollective.com/420couponcodes/8965926/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.kasinohai.com/nettikasinot">
+                <img class="sponsor" src="https://images.opencollective.com/kasinohai-com/41d4f51/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From a562a284965ea07cc4b9da6bc66b363ebfcb62e0 Mon Sep 17 00:00:00 2001
From: "eugeny.konstantinov" <jskonst@yandex.ru>
Date: Wed, 15 Apr 2020 18:36:54 +0300
Subject: [PATCH 0699/2348] Added test with subchild updated at check

---
 test/timestamps.test.js | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index 7a0f3f32273..5d28fabb92b 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -298,4 +298,43 @@ describe('timestamps', function() {
       assert.ok(doc.updatedAt > start, `${doc.updatedAt} >= ${start}`);
     });
   });
+
+  it('updates updatedAt when calling update on subchild', function() {
+    const subchildschema = new mongoose.Schema({
+      name: String
+    }, { timestamps: true });
+    const schema = new mongoose.Schema({
+      name: String,
+      subchild: subchildschema
+    }, { timestamps: true });
+    const parentSchema = new mongoose.Schema({
+      child: schema
+    }, { timestamps: true });
+
+    const Model = db.model('Test', parentSchema);
+
+    return co(function*() {
+      let doc = yield Model.create({ name: 'test', child: {
+        name: 'child',
+        subchild: {
+          name: 'subchild'
+        }
+      } });
+      assert.ok(doc.child.updatedAt);
+      const startTime = doc.createdAt;
+      yield new Promise(resolve => setTimeout(resolve), 25);
+
+      doc = yield Model.findOneAndUpdate({}, { $set: {
+        'child.subchild.name': 'subChildUpdated'
+      } }, { new: true });
+
+      assert.ok(doc.updatedAt.valueOf() > startTime,
+        `Parent Timestamp not updated: ${doc.updatedAt}`);
+      assert.ok(doc.child.updatedAt.valueOf() > startTime,
+        `Child Timestamp not updated: ${doc.updatedAt}`);
+      assert.ok(doc.child.subchild.updatedAt.valueOf() > startTime,
+        `SubChild Timestamp not updated: ${doc.updatedAt}`);
+    });
+  });
+
 });

From 8e871b0f29a173fbf5242c954b88b25942b3de06 Mon Sep 17 00:00:00 2001
From: "eugeny.konstantinov" <jskonst@yandex.ru>
Date: Thu, 16 Apr 2020 11:15:50 +0300
Subject: [PATCH 0700/2348] Changed object destructing to simple assignment

---
 lib/helpers/update/applyTimestampsToChildren.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 4c3e820abb5..b6e7444b569 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -79,7 +79,9 @@ function applyTimestampsToChildren(now, update, schema) {
         } else if (update.$set[key] && path.$isSingleNested) {
           applyTimestampsToSingleNested(update.$set[key], path, now);
         } else if (parentSchemaTypes.length > 0) {
-          for (const { parentPath, parentSchemaType } of parentSchemaTypes) {
+          for (const item of parentSchemaTypes) {
+            const  parentPath = item.parentPath 
+            const parentSchemaType = item.parentSchemaType;
             timestamps = parentSchemaType.schema.options.timestamps;
             createdAt = handleTimestampOption(timestamps, 'createdAt');
             updatedAt = handleTimestampOption(timestamps, 'updatedAt');

From b710d81593a1553d82c01df74e6cdd64710bdab6 Mon Sep 17 00:00:00 2001
From: "eugeny.konstantinov" <jskonst@yandex.ru>
Date: Thu, 16 Apr 2020 11:24:46 +0300
Subject: [PATCH 0701/2348] Fixed linter's errors

---
 lib/helpers/update/applyTimestampsToChildren.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index b6e7444b569..1b376170ab7 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -80,7 +80,7 @@ function applyTimestampsToChildren(now, update, schema) {
           applyTimestampsToSingleNested(update.$set[key], path, now);
         } else if (parentSchemaTypes.length > 0) {
           for (const item of parentSchemaTypes) {
-            const  parentPath = item.parentPath 
+            const parentPath = item.parentPath;
             const parentSchemaType = item.parentSchemaType;
             timestamps = parentSchemaType.schema.options.timestamps;
             createdAt = handleTimestampOption(timestamps, 'createdAt');

From afe447f43fab0906e026aea329611e7a60009371 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Apr 2020 10:11:06 -0400
Subject: [PATCH 0702/2348] chore: update opencollective sponsors

---
 index.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.pug b/index.pug
index 7258fd6a6f3..8052d6b4430 100644
--- a/index.pug
+++ b/index.pug
@@ -313,6 +313,12 @@ html(lang='en')
               <a href="https://www.kasinohai.com/nettikasinot">
                 <img class="sponsor" src="https://images.opencollective.com/kasinohai-com/41d4f51/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://onlinecasinoinformatie.com/">
+                <img class="sponsor" src="https://images.opencollective.com/ricardo-goncalves/3275f75/avatar/256.png" style="height: 100px">
+              </a>
+              <a href="https://onlinecasinoplatz.com/">
+                <img class="sponsor" src="https://images.opencollective.com/onlinecasinoplatz-com/8f8b647/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From b55fbaf11a1f8d02cbeb9713aaf216ea7798778e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Apr 2020 10:32:23 -0400
Subject: [PATCH 0703/2348] docs: use https in plugins link

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 8052d6b4430..1c89048fee4 100644
--- a/index.pug
+++ b/index.pug
@@ -101,7 +101,7 @@ html(lang='en')
           li
             a(href="docs/guide.html") Read the Docs
           li
-            a(href="http://plugins.mongoosejs.io") Discover Plugins
+            a(href="https://plugins.mongoosejs.io") Discover Plugins
       #follow
         ul
           li

From 56a346d763d58c439ac391a37145b9f84c861345 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Apr 2020 17:53:01 -0400
Subject: [PATCH 0704/2348] fix: upgrade mongodb -> 3.5.6 re: #8795

---
 .npmrc                       | 1 +
 lib/schema/objectid.js       | 2 +-
 package.json                 | 4 ++--
 test/schematype.cast.test.js | 2 +-
 4 files changed, 5 insertions(+), 4 deletions(-)
 create mode 100644 .npmrc

diff --git a/.npmrc b/.npmrc
new file mode 100644
index 00000000000..43c97e719a5
--- /dev/null
+++ b/.npmrc
@@ -0,0 +1 @@
+package-lock=false
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index aa7b4fb53c5..ee27f2ea20a 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -153,7 +153,7 @@ ObjectId.cast = function cast(caster) {
   if (caster === false) {
     caster = v => {
       if (!(v instanceof oid)) {
-        throw new Error();
+        throw new Error(v + ' is not an instance of ObjectId');
       }
       return v;
     };
diff --git a/package.json b/package.json
index 84a2e1a7a2f..158baedd142 100644
--- a/package.json
+++ b/package.json
@@ -19,9 +19,9 @@
   ],
   "license": "MIT",
   "dependencies": {
-    "bson": "~1.1.1",
+    "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.5.5",
+    "mongodb": "3.5.6",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",
diff --git a/test/schematype.cast.test.js b/test/schematype.cast.test.js
index e7cb29da704..2f89b53cd9c 100644
--- a/test/schematype.cast.test.js
+++ b/test/schematype.cast.test.js
@@ -85,7 +85,7 @@ describe('SchemaType.cast() (gh-7045)', function() {
     }
     assert.ok(threw);
 
-    objectid.cast(new ObjectId()); // Should not throw
+    objectid.cast(new ObjectId());
   });
 
   it('handles boolean', function() {

From cf9002269118ed78f5ea57f32e36650d6ae88176 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 18 Apr 2020 14:39:20 -0400
Subject: [PATCH 0705/2348] docs(validation): use `init()` as opposed to
 `once('index')` in `unique` example

Fix #8816
---
 test/docs/validation.test.js | 47 +++++++++++++-----------------------
 1 file changed, 17 insertions(+), 30 deletions(-)

diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 19f239d9e5c..9d75589a498 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -117,36 +117,40 @@ describe('validation docs', function() {
    */
 
   it('The `unique` Option is Not a Validator', function(done) {
-    var uniqueUsernameSchema = new Schema({
+    const uniqueUsernameSchema = new Schema({
       username: {
         type: String,
         unique: true
       }
     });
-    var U1 = db.model('U1', uniqueUsernameSchema);
-    var U2 = db.model('U2', uniqueUsernameSchema);
+    const U1 = db.model('U1', uniqueUsernameSchema);
+    const U2 = db.model('U2', uniqueUsernameSchema);
     // acquit:ignore:start
-    var remaining = 3;
+    this.timeout(5000);
+    let remaining = 2;
     // acquit:ignore:end
 
-    var dup = [{ username: 'Val' }, { username: 'Val' }];
-    U1.create(dup, function(error) {
+    const dup = [{ username: 'Val' }, { username: 'Val' }];
+    U1.create(dup, err => {
       // Race condition! This may save successfully, depending on whether
       // MongoDB built the index before writing the 2 docs.
       // acquit:ignore:start
-      // Avoid ESLint errors
-      error;
+      err;
       --remaining || done();
       // acquit:ignore:end
     });
 
-    // Need to wait for the index to finish building before saving,
-    // otherwise unique constraints may be violated.
-    U2.once('index', function(error) {
-      assert.ifError(error);
-      U2.create(dup, function(error) {
+    // You need to wait for Mongoose to finish building the `unique`
+    // index before writing. You only need to build indexes once for
+    // a given collection, so you normally don't need to do this
+    // in production. But, if you drop the database between tests,
+    // you will need to use `init()` to wait for the index build to finish.
+    U2.init().
+      then(() => U2.create(dup)).
+      catch(error => {
         // Will error, but will *not* be a mongoose validation error, it will be
         // a duplicate key error.
+        // See: https://masteringjs.io/tutorials/mongoose/e11000-duplicate-key
         assert.ok(error);
         assert.ok(!error.errors);
         assert.ok(error.message.indexOf('duplicate key error') !== -1);
@@ -154,23 +158,6 @@ describe('validation docs', function() {
         --remaining || done();
         // acquit:ignore:end
       });
-    });
-
-    // There's also a promise-based equivalent to the event emitter API.
-    // The `init()` function is idempotent and returns a promise that
-    // will resolve once indexes are done building;
-    U2.init().then(function() {
-      U2.create(dup, function(error) {
-        // Will error, but will *not* be a mongoose validation error, it will be
-        // a duplicate key error.
-        assert.ok(error);
-        assert.ok(!error.errors);
-        assert.ok(error.message.indexOf('duplicate key error') !== -1);
-        // acquit:ignore:start
-        --remaining || done();
-        // acquit:ignore:end
-      });
-    });
   });
 
   /**

From 72021333e707175b01840be0ef5275dd04a0e8d8 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 18 Apr 2020 23:41:23 +0200
Subject: [PATCH 0706/2348] test: repro #8806

---
 test/model.field.selection.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index 407aeeb87d2..eee4a3500ac 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -496,4 +496,32 @@ describe('model field selection', function() {
       assert.strictEqual(doc.settings.calendar.dateFormat, '1234');
     });
   });
+
+  it('when `select: true` in schema, works with $elemMatch in projection', function() {
+    return co(function*() {
+
+      const productSchema = new Schema({
+        attributes: {
+          select: true,
+          type: [{ name: String, group: String }]
+        }
+      });
+
+      const Product = db.model('Product', productSchema);
+
+      const attributes = [
+        { name: 'a', group: 'alpha' },
+        { name: 'b', group: 'beta' }
+      ];
+
+      yield Product.create({ name: 'test', attributes });
+
+      const product = yield Product.findOne()
+        .select({ attributes: { $elemMatch: { group: 'beta' } } });
+
+      assert.equal(product.attributes[0].name, 'b');
+      assert.equal(product.attributes[0].group, 'beta');
+      assert.equal(product.attributes.length, 1);
+    });
+  });
 });
\ No newline at end of file

From 55fce00150ee17339a6ba8a59a9df1239892d88a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 19 Apr 2020 00:03:05 +0200
Subject: [PATCH 0707/2348] test: selection specified in query overwrites
 option in schema

---
 test/model.field.selection.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index eee4a3500ac..adf54722d25 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -524,4 +524,19 @@ describe('model field selection', function() {
       assert.equal(product.attributes.length, 1);
     });
   });
+
+  it('selection specified in query overwrites option in schema', function() {
+    return co(function*() {
+      const productSchema = new Schema({ name: { type: String, select: true } });
+
+      const Product = db.model('Product', productSchema);
+
+
+      yield Product.create({ name: 'Computer' });
+
+      const product = yield Product.findOne().select('-name');
+
+      assert.equal(product.name, 'Computer');
+    });
+  });
 });
\ No newline at end of file

From 4d66c4754e89db2cb10cc341f77e81875dcba598 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 19 Apr 2020 00:10:22 +0200
Subject: [PATCH 0708/2348] make applyPaths accept user provided value re:
 #8806

---
 lib/queryhelpers.js | 119 ++++++++++++++++++++++----------------------
 1 file changed, 60 insertions(+), 59 deletions(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 343c3b175c4..33868db0b16 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -120,18 +120,17 @@ exports.applyPaths = function applyPaths(fields, schema) {
   // determine if query is selecting or excluding fields
   let exclude;
   let keys;
-  let ki;
-  let field;
+  let keyIndex;
 
   if (fields) {
     keys = Object.keys(fields);
-    ki = keys.length;
+    keyIndex = keys.length;
 
-    while (ki--) {
-      if (keys[ki][0] === '+') {
+    while (keyIndex--) {
+      if (keys[keyIndex][0] === '+') {
         continue;
       }
-      field = fields[keys[ki]];
+      const field = fields[keys[keyIndex]];
       // Skip `$meta` and `$slice`
       if (!isDefiningProjection(field)) {
         continue;
@@ -148,63 +147,13 @@ exports.applyPaths = function applyPaths(fields, schema) {
   const excluded = [];
   const stack = [];
 
-  const analyzePath = function(path, type) {
-    const plusPath = '+' + path;
-    const hasPlusPath = fields && plusPath in fields;
-    if (hasPlusPath) {
-      // forced inclusion
-      delete fields[plusPath];
-    }
-
-    if (typeof type.selected !== 'boolean') return;
-
-    if (hasPlusPath) {
-      // forced inclusion
-      delete fields[plusPath];
-
-      // if there are other fields being included, add this one
-      // if no other included fields, leave this out (implied inclusion)
-      if (exclude === false && keys.length > 1 && !~keys.indexOf(path)) {
-        fields[path] = 1;
-      }
-
-      return;
-    }
-
-    // check for parent exclusions
-    const pieces = path.split('.');
-    let cur = '';
-    for (let i = 0; i < pieces.length; ++i) {
-      cur += cur.length ? '.' + pieces[i] : pieces[i];
-      if (excluded.indexOf(cur) !== -1) {
-        return;
-      }
-    }
-
-    // Special case: if user has included a parent path of a discriminator key,
-    // don't explicitly project in the discriminator key because that will
-    // project out everything else under the parent path
-    if (!exclude && get(type, 'options.$skipDiscriminatorCheck', false)) {
-      let cur = '';
-      for (let i = 0; i < pieces.length; ++i) {
-        cur += (cur.length === 0 ? '' : '.') + pieces[i];
-        const projection = get(fields, cur, false);
-        if (projection && typeof projection !== 'object') {
-          return;
-        }
-      }
-    }
-
-    (type.selected ? selected : excluded).push(path);
-    return path;
-  };
-
   analyzeSchema(schema);
 
   switch (exclude) {
     case true:
       for (let i = 0; i < excluded.length; ++i) {
-        fields[excluded[i]] = 0;
+        const fieldSelectionValue = fields[excluded[i]] != null ? fields[excluded[i]] : 0;
+        fields[excluded[i]] = fieldSelectionValue;
       }
       break;
     case false:
@@ -215,7 +164,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
         fields._id = 0;
       }
       for (let i = 0; i < selected.length; ++i) {
-        fields[selected[i]] = 1;
+        const fieldSelectionValue = fields[selected[i]] != null ? fields[selected[i]] : 1;
+        fields[selected[i]] = fieldSelectionValue;
       }
       break;
     case undefined:
@@ -271,6 +221,57 @@ exports.applyPaths = function applyPaths(fields, schema) {
     stack.pop();
     return addedPaths;
   }
+
+  function analyzePath(path, type) {
+    const plusPath = '+' + path;
+    const hasPlusPath = fields && plusPath in fields;
+    if (hasPlusPath) {
+      // forced inclusion
+      delete fields[plusPath];
+    }
+
+    if (typeof type.selected !== 'boolean') return;
+
+    if (hasPlusPath) {
+      // forced inclusion
+      delete fields[plusPath];
+
+      // if there are other fields being included, add this one
+      // if no other included fields, leave this out (implied inclusion)
+      if (exclude === false && keys.length > 1 && !~keys.indexOf(path)) {
+        fields[path] = 1;
+      }
+
+      return;
+    }
+
+    // check for parent exclusions
+    const pieces = path.split('.');
+    let cur = '';
+    for (let i = 0; i < pieces.length; ++i) {
+      cur += cur.length ? '.' + pieces[i] : pieces[i];
+      if (excluded.indexOf(cur) !== -1) {
+        return;
+      }
+    }
+
+    // Special case: if user has included a parent path of a discriminator key,
+    // don't explicitly project in the discriminator key because that will
+    // project out everything else under the parent path
+    if (!exclude && get(type, 'options.$skipDiscriminatorCheck', false)) {
+      let cur = '';
+      for (let i = 0; i < pieces.length; ++i) {
+        cur += (cur.length === 0 ? '' : '.') + pieces[i];
+        const projection = get(fields, cur, false);
+        if (projection && typeof projection !== 'object') {
+          return;
+        }
+      }
+    }
+
+    (type.selected ? selected : excluded).push(path);
+    return path;
+  }
 };
 
 /*!

From ec0fb12ac3d10a2145c434114fbf76e9344512fe Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 19 Apr 2020 00:18:23 +0200
Subject: [PATCH 0709/2348] fix test

---
 test/model.field.selection.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index adf54722d25..1d63dcac7c8 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -527,14 +527,14 @@ describe('model field selection', function() {
 
   it('selection specified in query overwrites option in schema', function() {
     return co(function*() {
-      const productSchema = new Schema({ name: { type: String, select: true } });
+      const productSchema = new Schema({ name: { type: String, select: false } });
 
       const Product = db.model('Product', productSchema);
 
 
       yield Product.create({ name: 'Computer' });
 
-      const product = yield Product.findOne().select('-name');
+      const product = yield Product.findOne().select('name');
 
       assert.equal(product.name, 'Computer');
     });

From fdaf5395228cf5b15fabe189d690522671d986a1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 19 Apr 2020 00:21:29 +0200
Subject: [PATCH 0710/2348] revert using passed value on exclusion to
 projection

---
 lib/queryhelpers.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 33868db0b16..74707d46930 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -152,8 +152,7 @@ exports.applyPaths = function applyPaths(fields, schema) {
   switch (exclude) {
     case true:
       for (let i = 0; i < excluded.length; ++i) {
-        const fieldSelectionValue = fields[excluded[i]] != null ? fields[excluded[i]] : 0;
-        fields[excluded[i]] = fieldSelectionValue;
+        fields[excluded[i]] = 0;
       }
       break;
     case false:

From f1c124c3fc0527541a9b089e82bf45f761aa4538 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Sun, 19 Apr 2020 22:50:27 +1200
Subject: [PATCH 0711/2348] docs(api): detail what the insertMany Promise
 resolves to

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index e1efddacfd6..7951e408aef 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3263,7 +3263,7 @@ Model.startSession = function() {
  * @param {Boolean} [options.rawResult = false] if false, the returned promise resolves to the documents that passed mongoose document validation. If `true`, will return the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~insertWriteOpCallback) with a `mongoose` property that contains `validationErrors` if this is an unordered `insertMany`.
  * @param {Boolean} [options.lean = false] if `true`, skips hydrating and validating the documents. This option is useful if you need the extra performance, but Mongoose won't validate the documents before inserting.
  * @param {Function} [callback] callback
- * @return {Promise}
+ * @return {Promise} resolving to the raw result from the MongoDB driver if `options.rawResult` was `true`, or the documents that passed validation, otherwise
  * @api public
  */
 

From 8fea1d9121b5e87eb66d45b667fd2bd5baed0f57 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 19 Apr 2020 12:16:28 -0400
Subject: [PATCH 0712/2348] fix(document): avoid calling `$set()` on object
 keys if object path isn't in schema

Re: #8751
---
 lib/document.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/document.js b/lib/document.js
index c758e4ce3db..d0809fa24dd 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -947,6 +947,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
         path[key] != null &&
         pathtype !== 'virtual' &&
         pathtype !== 'real' &&
+        pathtype !== 'adhocOrUndefined' &&
         !(this.$__path(pathName) instanceof MixedSchema) &&
         !(this.schema.paths[pathName] &&
         this.schema.paths[pathName].options &&

From 32c5ed0945c89fd208e1f9d4439bdad3f216c16c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 19 Apr 2020 12:18:26 -0400
Subject: [PATCH 0713/2348] fix(schematype): throw error if default is set to a
 schema instance

Fix #8751
---
 lib/schematype.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/schematype.js b/lib/schematype.js
index c1e197b4374..6437c1738f3 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -244,6 +244,12 @@ SchemaType.prototype.default = function(val) {
       this.defaultValue = void 0;
       return void 0;
     }
+
+    if (val != null && val.instanceOfSchema) {
+      throw new MongooseError('Cannot set default value of path `' + this.path +
+        '` to a mongoose Schema instance.');
+    }
+
     this.defaultValue = val;
     return this.defaultValue;
   } else if (arguments.length > 1) {

From c9ebc5157305c5c596a37095721ff3efc34648e7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 20 Apr 2020 05:49:25 +0200
Subject: [PATCH 0714/2348] refactor for loops to for-of whenever possible

---
 lib/aggregate.js  |  3 +--
 lib/connection.js |  4 ++--
 lib/document.js   | 11 +++++------
 lib/model.js      |  6 ++++--
 4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index abc51db118b..5bfd82215f4 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -370,8 +370,7 @@ Aggregate.prototype.unwind = function() {
   const args = utils.args(arguments);
 
   const res = [];
-  for (let i = 0; i < args.length; ++i) {
-    const arg = args[i];
+  for (const arg of args) {
     if (arg && typeof arg === 'object') {
       res.push({ $unwind: arg });
     } else if (typeof arg === 'string') {
diff --git a/lib/connection.js b/lib/connection.js
index bcbaf9c157d..12f0517aa06 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -109,8 +109,8 @@ Object.defineProperty(Connection.prototype, 'readyState', {
     if (this._readyState !== val) {
       this._readyState = val;
       // [legacy] loop over the otherDbs on this connection and change their state
-      for (let i = 0; i < this.otherDbs.length; i++) {
-        this.otherDbs[i].readyState = val;
+      for (const db of this.otherDbs) {
+        db.readyState = val;
       }
 
       // loop over relatedDbs on this connection and change their state
diff --git a/lib/document.js b/lib/document.js
index c758e4ce3db..e599a01b0d0 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -532,8 +532,7 @@ Document.prototype.$__init = function(doc, opts) {
   // If doc._id is not null or undefined
   if (doc._id != null && opts.populated && opts.populated.length) {
     const id = String(doc._id);
-    for (let i = 0; i < opts.populated.length; ++i) {
-      const item = opts.populated[i];
+    for (const item of opts.populated) {
       if (item.isVirtual) {
         this.populated(item.path, utils.getValue(item.path, doc), item);
       } else {
@@ -3726,13 +3725,13 @@ Document.prototype.depopulate = function(path) {
 
     const keys = Object.keys(populated);
 
-    for (let i = 0; i < keys.length; i++) {
-      populatedIds = this.populated(keys[i]);
+    for (const key of keys) {
+      populatedIds = this.populated(key);
       if (!populatedIds) {
         continue;
       }
-      delete populated[keys[i]];
-      this.$set(keys[i], populatedIds);
+      delete populated[key];
+      this.$set(key, populatedIds);
     }
     return this;
   }
diff --git a/lib/model.js b/lib/model.js
index e1efddacfd6..21e56c74d83 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4015,12 +4015,14 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
       paths = paths.filter(p => {
         const pieces = p.split('.');
         let cur = pieces[0];
-        for (let i = 0; i < pieces.length; ++i) {
+
+        for (const piece of pieces) {
           if (_pathsToValidate.has(cur)) {
             return true;
           }
-          cur += '.' + pieces[i];
+          cur += '.' + piece;
         }
+
         return _pathsToValidate.has(p);
       });
     }

From fce435b3b73e30f3ed0d5e933530d6d4bc1dd944 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 20 Apr 2020 06:59:45 +0200
Subject: [PATCH 0715/2348] (docs) make questions anchorable on faq

---
 docs/faq.pug | 45 ++++++++++++++++++++++++---------------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index c8365bb72a5..c3de778b364 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -30,7 +30,9 @@ block content
       <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
     </div>
 
-    **Q**. Why don't my changes to arrays get saved when I update an element
+    <hr id="array-changes-not-saved" />
+
+    <a href="#array-changes-not-saved">**Q**</a>. Why don't my changes to arrays get saved when I update an element
     directly?
 
     ```javascript
@@ -57,7 +59,7 @@ block content
 
     <hr id="unique-doesnt-work" />
 
-    **Q**. I declared a schema property as `unique` but I can still save
+    <a href="#unique-doesnt-work">**Q**</a>. I declared a schema property as `unique` but I can still save
     duplicates. What gives?
 
     **A**. Mongoose doesn't handle `unique` on its own: `{ name: { type: String, unique: true } }`
@@ -109,7 +111,7 @@ block content
 
     <hr id="nested-properties" />
 
-    **Q**. When I have a nested property in a schema, mongoose adds empty objects by default. Why?
+    <a href="#nested-properties">**Q**</a>. When I have a nested property in a schema, mongoose adds empty objects by default. Why?
 
     ```javascript
     var schema = new mongoose.Schema({
@@ -139,7 +141,7 @@ block content
 
     <hr id="destructured-imports" />
 
-    **Q**. When I use named imports like `import { set } from 'mongoose'`, I
+    <a href="#destructured-imports">**Q**</a>. When I use named imports like `import { set } from 'mongoose'`, I
     get a `TypeError`. What causes this issue and how can I fix it?
 
     **A**. The only import syntax Mongoose supports is `import mongoose from 'mongoose'`.
@@ -164,7 +166,7 @@ block content
 
     <hr id="arrow-functions" />
 
-    **Q**. I'm using an arrow function for a [virtual](./guide.html#virtuals), [middleware](./middleware.html), [getter](./api.html#schematype_SchemaType-get)/[setter](./api.html#schematype_SchemaType-set), or [method](./guide.html#methods) and the value of `this` is wrong.
+    <a href="#arrow-functions">**Q**</a>. I'm using an arrow function for a [virtual](./guide.html#virtuals), [middleware](./middleware.html), [getter](./api.html#schematype_SchemaType-get)/[setter](./api.html#schematype_SchemaType-set), or [method](./guide.html#methods) and the value of `this` is wrong.
 
     **A**. Arrow functions [handle the `this` keyword much differently than conventional functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this).
     Mongoose getters/setters depend on `this` to give you access to the document that you're writing to, but this functionality does not work with arrow functions. Do **not** use arrow functions for mongoose getters/setters unless do not intend to access the document in the getter/setter.
@@ -194,7 +196,7 @@ block content
 
     <hr id="type-key">
 
-    **Q**. I have an embedded property named `type` like this:
+    <a href="#type-key">**Q**</a>. I have an embedded property named `type` like this:
 
     ```javascript
     const holdingSchema = new Schema({
@@ -238,7 +240,7 @@ block content
 
     <hr id="populate_sort_order" />
 
-    **Q**. I'm populating a nested property under an array like the below code:
+    <a href="#populate_sort_order">**Q**</a>. I'm populating a nested property under an array like the below code:
 
     ```javascript
       new Schema({
@@ -255,7 +257,7 @@ block content
 
     <hr id="model_functions_hanging" />
 
-    **Q**. All function calls on my models hang, what am I doing wrong?
+    <a href="#model_functions_hanging">**Q**</a>. All function calls on my models hang, what am I doing wrong?
 
     **A**. By default, mongoose will buffer your function calls until it can
     connect to MongoDB. Read the [buffering section of the connection docs](./connections.html#buffering)
@@ -263,7 +265,7 @@ block content
 
     <hr id="enable_debugging" />
 
-    **Q**. How can I enable debugging?
+    <a href="#enable_debugging">**Q**</a>. How can I enable debugging?
 
     **A**. Set the `debug` option to `true`:
 
@@ -279,7 +281,7 @@ block content
 
     <hr id="callback_never_executes" />
 
-    **Q**. My `save()` callback never executes. What am I doing wrong?
+    <a href="#callback_never_executes">**Q**</a>. My `save()` callback never executes. What am I doing wrong?
 
     **A**. All `collection` actions (insert, remove, queries, etc.) are queued
     until the `connection` opens. It is likely that an error occurred while
@@ -304,14 +306,14 @@ block content
 
     <hr id="creating_connections" />
 
-    **Q**. Should I create/destroy a new connection for each database operation?
+    <a href="#creating_connections">**Q**</a>. Should I create/destroy a new connection for each database operation?
 
     **A**. No. Open your connection when your application starts up and leave
     it open until the application shuts down.
 
     <hr id="overwrite-model-error" />
 
-    **Q**. Why do I get "OverwriteModelError: Cannot overwrite .. model once
+    <a href="#overwrite-model-error">**Q**</a>. Why do I get "OverwriteModelError: Cannot overwrite .. model once
     compiled" when I use nodemon / a testing framework?
 
     **A**. `mongoose.model('ModelName', schema)` requires 'ModelName' to be
@@ -336,7 +338,7 @@ block content
 
     <hr id="array-defaults" />
 
-    **Q**. How can I change mongoose's default behavior of initializing an array
+    <a href="#array-defaults">**Q**</a>. How can I change mongoose's default behavior of initializing an array
     path to an empty array so that I can require real data on document creation?
 
     **A**. You can set the default of the array to a function that returns `undefined`.
@@ -348,8 +350,9 @@ block content
       }
     });
     ```
-
-    **Q**. How can I initialize an array path to `null`?
+    <hr id="initialize-array-path-null" />
+    
+    <a href="#initialize-array-path-null">**Q**</a>. How can I initialize an array path to `null`?
 
     **A**. You can set the default of the array to a function that returns `null`.
     ```javascript
@@ -363,7 +366,7 @@ block content
 
     <hr id="aggregate-casting" />
 
-    **Q**. Why does my aggregate $match fail to return the document that my find query
+    <a href="#aggregate-casting">**Q**</a>. Why does my aggregate $match fail to return the document that my find query
     returns when working with dates?
 
     **A**. Mongoose does not cast aggregation pipeline stages because with $project,
@@ -373,7 +376,7 @@ block content
 
     <hr id="date_changes" />
 
-    **Q**. Why don't in-place modifications to date objects
+    <a href="#date_changes">**Q**</a>. Why don't in-place modifications to date objects
     (e.g. `date.setMonth(1);`) get saved?
 
     ```javascript
@@ -397,7 +400,7 @@ block content
 
     <hr id="parallel_saves" />
 
-    **Q**. Why does calling `save()` multiple times on the same document in parallel only let
+    <a href="#parallel_saves">**Q**</a>. Why does calling `save()` multiple times on the same document in parallel only let
     the first save call succeed and return ParallelSaveErrors for the rest?
 
     **A**. Due to the asynchronous nature of validation and middleware in general, calling
@@ -406,14 +409,14 @@ block content
 
     <hr id="objectid-validation" />
 
-    **Q**. Why is **any** 12 character string successfully cast to an ObjectId?
+    <a href="#objectid-validation">**Q**</a>. Why is **any** 12 character string successfully cast to an ObjectId?
 
     **A**. Technically, any 12 character string is a valid [ObjectId](https://docs.mongodb.com/manual/reference/bson-types/#objectid).
     Consider using a regex like `/^[a-f0-9]{24}$/` to test whether a string is exactly 24 hex characters.
 
     <hr id="slow-localhost" />
 
-    **Q**. I'm connecting to `localhost` and it takes me nearly 1 second to connect. How do I fix this?
+    <a href="#slow-localhost">**Q**</a>. I'm connecting to `localhost` and it takes me nearly 1 second to connect. How do I fix this?
 
     **A**. The underlying MongoDB driver defaults to looking for IPv6 addresses, so the most likely cause is that your `localhost` DNS mapping isn't configured to handle IPv6. Use `127.0.0.1` instead of `localhost` or use the `family` option as shown in the [connection docs](https://mongoosejs.com/docs/connections.html#options).
 
@@ -427,7 +430,7 @@ block content
 
     <hr id="map-keys-strings" />
 
-    **Q**. Why do keys in Mongoose Maps have to be strings?
+    <a href="#map-keys-strings">**Q**</a>. Why do keys in Mongoose Maps have to be strings?
 
     **A**. Because the Map eventually gets stored in MongoDB where the keys must be strings.
 

From 0da8eff6a84e29ed18c4c348f1d66d3196883d21 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 20 Apr 2020 22:20:29 +0200
Subject: [PATCH 0716/2348] add eslint rules, space-in-parens "never"

---
 lib/options/PopulateOptions.js      | 2 +-
 lib/types/embedded.js               | 2 +-
 package.json                        | 7 ++++++-
 test/helpers/clone.test.js          | 2 +-
 test/model.findOneAndUpdate.test.js | 4 ++--
 test/model.populate.test.js         | 4 ++--
 6 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/lib/options/PopulateOptions.js b/lib/options/PopulateOptions.js
index a438dd1538f..b60d45abda6 100644
--- a/lib/options/PopulateOptions.js
+++ b/lib/options/PopulateOptions.js
@@ -17,7 +17,7 @@ class PopulateOptions {
 
 
     if (obj.perDocumentLimit != null && obj.limit != null) {
-      throw new Error('Can not use `limit` and `perDocumentLimit` at the same time. Path: `' + obj.path + '`.' );
+      throw new Error('Can not use `limit` and `perDocumentLimit` at the same time. Path: `' + obj.path + '`.');
     }
   }
 }
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 5e817bf0803..4296d6c7ac7 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -207,7 +207,7 @@ EmbeddedDocument.prototype.$__remove = function(cb) {
  */
 
 EmbeddedDocument.prototype.remove = function(options, fn) {
-  if ( typeof options === 'function' && !fn ) {
+  if (typeof options === 'function' && !fn) {
     fn = options;
     options = undefined;
   }
diff --git a/package.json b/package.json
index 158baedd142..e51aa5df2fd 100644
--- a/package.json
+++ b/package.json
@@ -130,6 +130,11 @@
       "func-call-spacing": "error",
       "no-trailing-spaces": "error",
       "no-undef": "error",
+      "no-unneeded-ternary": "error",
+      "no-const-assign": "error",
+      "no-useless-rename": "error",
+      "no-dupe-keys": "error",
+      "space-in-parens": ["error", "never"],
       "key-spacing": [
         2,
         {
@@ -192,4 +197,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
+}
\ No newline at end of file
diff --git a/test/helpers/clone.test.js b/test/helpers/clone.test.js
index 367682775bb..7e0e7132638 100644
--- a/test/helpers/clone.test.js
+++ b/test/helpers/clone.test.js
@@ -204,7 +204,7 @@ describe('clone', () => {
     it('does nothing', () => {
       class BeeSon {
         constructor() { this.myAttr = 'myAttrVal'; }
-        toBSON( ) {}
+        toBSON() {}
       }
       const base = new BeeSon();
       const cloned = clone(base, { bson: true });
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index b934faf9e7a..8502ea10227 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -865,10 +865,10 @@ describe('model: findOneAndUpdate:', function() {
 
     Thing.findOneAndUpdate({ _id: key }, { $set: { flag: false } }, { upsert: true, new: false, rawResult: true }).exec(function(err, rawResult) {
       assert.ifError(err);
-      assert.equal(rawResult.lastErrorObject.updatedExisting, false );
+      assert.equal(rawResult.lastErrorObject.updatedExisting, false);
       Thing.findOneAndUpdate({ _id: key }, { $set: { flag: true } }, { upsert: true, new: false, rawResult: true }).exec(function(err, rawResult2) {
         assert.ifError(err);
-        assert.equal(rawResult2.lastErrorObject.updatedExisting, true );
+        assert.equal(rawResult2.lastErrorObject.updatedExisting, true);
         assert.equal(rawResult2.value._id, key);
         assert.equal(rawResult2.value.flag, false);
         done();
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 03f1d12ceaa..973f71d3f8f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -6438,9 +6438,9 @@ describe('model: populate:', function() {
           }).
           then(function(results) {
             assert.equal(results.length, 2);
-            assert.equal(results[0].activity.kind, 'gh5858_1' );
+            assert.equal(results[0].activity.kind, 'gh5858_1');
             assert.equal(results[0].activity.postedBy.name, 'val');
-            assert.equal(results[1].activity.kind, 'gh5858_2' );
+            assert.equal(results[1].activity.kind, 'gh5858_2');
             assert.equal(results[1].activity.postedBy, null);
           });
       });

From 4100452e05710898c3e63a3f4e051a38cdca7304 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 20 Apr 2020 22:24:39 +0200
Subject: [PATCH 0717/2348] Add spaced comment rule

---
 lib/schema.js           | 2 +-
 package.json            | 6 ++++++
 test/connection.test.js | 4 ++--
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 16e5dd0de33..5d63bb5718e 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -926,7 +926,7 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         if (options.typeKey) {
           childSchemaOptions.typeKey = options.typeKey;
         }
-        //propagate 'strict' option to child schema
+        // propagate 'strict' option to child schema
         if (options.hasOwnProperty('strict')) {
           childSchemaOptions.strict = options.strict;
         }
diff --git a/package.json b/package.json
index e51aa5df2fd..d12a425214d 100644
--- a/package.json
+++ b/package.json
@@ -135,6 +135,12 @@
       "no-useless-rename": "error",
       "no-dupe-keys": "error",
       "space-in-parens": ["error", "never"],
+      "spaced-comment": [2, "always", {
+        "block": {
+          "markers": ["!"],
+          "balanced": true
+        }
+      }],
       "key-spacing": [
         2,
         {
diff --git a/test/connection.test.js b/test/connection.test.js
index 1fd381360c4..b034f9a865d 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -700,12 +700,12 @@ describe('connections:', function() {
     db.then(function() {
       setTimeout(function() {
         // TODO: enforce error.message, right now get a confusing error
-        /*db.collection('Test').insertOne({x:1}, function(error) {
+        /* db.collection('Test').insertOne({x:1}, function(error) {
           assert.ok(error);
 
           //assert.ok(error.message.indexOf('pool was destroyed') !== -1, error.message);
           done();
-        });*/
+        }); */
 
         let threw = false;
         try {

From a1260a0541a4c8ca45cf36ffd307973665918198 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 20 Apr 2020 22:33:10 +0200
Subject: [PATCH 0718/2348] make eslint rules more strict, no-extra-semi no
 space before semicolons, no throwing literals, no spaced functions

---
 package.json | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/package.json b/package.json
index d12a425214d..2e68d50ecb3 100644
--- a/package.json
+++ b/package.json
@@ -174,6 +174,10 @@
         "as-needed"
       ],
       "semi": "error",
+      "no-extra-semi": "error",
+      "semi-spacing": "error",
+      "no-spaced-func": "error",
+      "no-throw-literal": "error",
       "space-before-blocks": "error",
       "space-before-function-paren": [
         "error",

From 4442b1e25abd7fe460e0b85644664ae7143a6039 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 20 Apr 2020 22:36:22 +0200
Subject: [PATCH 0719/2348] Use "error" instead of 2 in eslint rules

---
 package.json | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/package.json b/package.json
index 2e68d50ecb3..c2875ab0437 100644
--- a/package.json
+++ b/package.json
@@ -135,21 +135,21 @@
       "no-useless-rename": "error",
       "no-dupe-keys": "error",
       "space-in-parens": ["error", "never"],
-      "spaced-comment": [2, "always", {
+      "spaced-comment": ["error", "always", {
         "block": {
           "markers": ["!"],
           "balanced": true
         }
       }],
       "key-spacing": [
-        2,
+        "error",
         {
           "beforeColon": false,
           "afterColon": true
         }
       ],
       "comma-spacing": [
-        2,
+        "error",
         {
           "before": false,
           "after": true
@@ -157,14 +157,14 @@
       ],
       "array-bracket-spacing": 1,
       "object-curly-spacing": [
-        2,
+        "error",
         "always"
       ],
       "comma-dangle": [
-        2,
+        "error",
         "never"
       ],
-      "no-unreachable": 2,
+      "no-unreachable": "error",
       "quotes": [
         "error",
         "single"

From e328b98df8f73134bdcaff10d32b0e087439848f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 20 Apr 2020 17:54:08 -0400
Subject: [PATCH 0720/2348] chore: release 5.9.10

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index db4f4fd973b..2d4aa45da6c 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.9.10 / 2020-04-20
+===================
+ * fix: upgrade mongodb -> 3.5.6, bson -> 1.1.4 #8719
+ * fix(document): avoid calling `$set()` on object keys if object path isn't in schema #8751
+ * fix(timestamps): handle timestamps on doubly nested subdocuments #8799
+ * fix(schematype): throw error if default is set to a schema instance #8751
+ * fix: handle $elemMatch projection with `select: false` in schema #8818 #8806 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: make FAQ questions more linkable #8825 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(validation): use `init()` as opposed to `once('index')` in `unique` example #8816
+ * docs: clarify `insertMany()` return value #8820 [dandv](https://github.com/dandv)
+ * docs(populate+query): fix typos #8793 #8794 [dandv](https://github.com/dandv)
+ * docs(model): document skipId parameter #8791 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.9.9 / 2020-04-13
 ==================
  * fix(model): make Model.bulkWrite accept `strict` option #8782 #8788 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index c2875ab0437..fff8835e7e6 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.9",
+  "version": "5.9.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 817538c4598380d90b33c14b73e456d96e8fdaac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Apr 2020 12:02:52 -0400
Subject: [PATCH 0721/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 1c89048fee4..960b37a55d4 100644
--- a/index.pug
+++ b/index.pug
@@ -319,6 +319,9 @@ html(lang='en')
               <a href="https://onlinecasinoplatz.com/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinoplatz-com/8f8b647/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
+                <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From ca56368d938f802d35ed569f7e92cef7d70afe95 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 21 Apr 2020 18:55:30 -0400
Subject: [PATCH 0722/2348] chore(release-items): remove unnecessary `-pre`
 step that we don't use anymore

This step makes it awkward to push to gh-pages in between releases
---
 release-items.md | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/release-items.md b/release-items.md
index 12ab9a5daca..3dad44f0170 100644
--- a/release-items.md
+++ b/release-items.md
@@ -9,8 +9,7 @@
 7.  update mongoosejs.com (see "updating the website" below)
 8.  tweet changelog link from [@mongoosejs](https://twitter.com/mongoosejs)
 9.  Announce on mongoosejsteam slack channel
-10. change package.json version to next patch version suffixed with '-pre' and commit "now working on x.x.x"
-11. if this is a legacy release, `git merge` changes into master.
+10. if this is a legacy release, `git merge` changes into master.
 
 ## updating the website
 

From 371c49a14775fe846f0f7747f3106105ef970354 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 11:17:41 +0200
Subject: [PATCH 0723/2348] add node 13, and 14 to travis

---
 .travis.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.travis.yml b/.travis.yml
index 5bdee1541db..687ab6ba270 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: node_js
 sudo: false
-node_js: [12, 11, 10, 9, 8, 7, 6, 5, 4]
+node_js: [14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4]
 install:
   - travis_retry npm install
 before_script:

From da1c6a06168fdbe5705908931287dcee5bb25276 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 13:35:06 +0200
Subject: [PATCH 0724/2348] test: repro #8835

---
 test/query.cursor.test.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index c38a2327edc..b2969cd6ef9 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -531,4 +531,36 @@ describe('QueryCursor', function() {
       assert.deepEqual(docs.map(d => d.order), [1, 2, 3]);
     });
   });
+
+  it('closing query cursor emits `close` event only once (gh-8835)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    const cursor = User.find().cursor();
+    cursor.on('data', (_)=>{});
+
+    let closeEventTriggeredCount = 0;
+    cursor.on('close', () => closeEventTriggeredCount++);
+
+    setTimeout(() => {
+      assert.equal(closeEventTriggeredCount, 1);
+      done();
+    }, 20);
+  });
+
+  it('closing aggregation cursor emits `close` event only once (gh-8835)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    const cursor = User.aggregate([{ $match: {} }]).cursor().exec();
+    cursor.on('data', (_)=>{});
+
+    let closeEventTriggeredCount = 0;
+    cursor.on('close', () => closeEventTriggeredCount++);
+
+
+    setTimeout(() => {
+      assert.equal(closeEventTriggeredCount, 1);
+      done();
+    }, 20);
+
+  });
 });

From 2b25b8477f984707bc3205bb5068c8a0ffefe406 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 13:37:29 +0200
Subject: [PATCH 0725/2348] do not close stream at the end of _read if it's
 closed automatically

---
 lib/cursor/AggregationCursor.js | 5 ++++-
 lib/cursor/QueryCursor.js       | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 51dd51919cc..16bcdbbcd5c 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -86,7 +86,10 @@ AggregationCursor.prototype._read = function() {
           return _this.emit('error', error);
         }
         setTimeout(function() {
-          _this.emit('close');
+          // on node >= 14 streams close automatically (gh-8834)
+          if (!_this.destroyed) {
+            _this.emit('close');
+          }
         }, 0);
       });
       return;
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index de0108a45b8..f20014eae87 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -88,7 +88,10 @@ QueryCursor.prototype._read = function() {
           return _this.emit('error', error);
         }
         setTimeout(function() {
-          _this.emit('close');
+          // on node >= 14 streams close automatically (gh-8834)
+          if (!_this.destroyed) {
+            _this.emit('close');
+          }
         }, 0);
       });
       return;

From 391c52c00178d41fec3fe59bdd415e7250a4074c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 13:44:29 +0200
Subject: [PATCH 0726/2348] remove unused variable

---
 test/query.cursor.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index b2969cd6ef9..b122cff5e14 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -536,7 +536,7 @@ describe('QueryCursor', function() {
     const User = db.model('User', new Schema({ name: String }));
 
     const cursor = User.find().cursor();
-    cursor.on('data', (_)=>{});
+    cursor.on('data', ()=>{});
 
     let closeEventTriggeredCount = 0;
     cursor.on('close', () => closeEventTriggeredCount++);
@@ -551,7 +551,7 @@ describe('QueryCursor', function() {
     const User = db.model('User', new Schema({ name: String }));
 
     const cursor = User.aggregate([{ $match: {} }]).cursor().exec();
-    cursor.on('data', (_)=>{});
+    cursor.on('data', ()=>{});
 
     let closeEventTriggeredCount = 0;
     cursor.on('close', () => closeEventTriggeredCount++);

From 4d31dbd7e4d7682c0998a41ef8dda72fdb68e4c2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 13:51:35 +0200
Subject: [PATCH 0727/2348] docs: add options.path for Model.populate(...)

---
 lib/model.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/model.js b/lib/model.js
index e1efddacfd6..35bf3fe03a1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4228,6 +4228,7 @@ Model.geoSearch = function(conditions, options, callback) {
  *
  * @param {Document|Array} docs Either a single document or array of documents to populate.
  * @param {Object} options A hash of key/val (path, options) used for population.
+ * @param {string} [options.path=null] The path to populate.
  * @param {boolean} [options.retainNullValues=false] by default, Mongoose removes null and undefined values from populated arrays. Use this option to make `populate()` retain `null` and `undefined` array entries.
  * @param {boolean} [options.getters=false] if true, Mongoose will call any getters defined on the `localField`. By default, Mongoose gets the raw value of `localField`. For example, you would need to set this option to `true` if you wanted to [add a `lowercase` getter to your `localField`](/docs/schematypes.html#schematype-options).
  * @param {boolean} [options.clone=false] When you do `BlogPost.find().populate('author')`, blog posts with the same author will share 1 copy of an `author` doc. Enable this option to make Mongoose clone populated docs before assigning them.

From e0a738fb01376104bf5ee01a69babe278b87a4c4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 14:02:52 +0200
Subject: [PATCH 0728/2348] (docs) add string as an option to
 Model.populate(...)

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 35bf3fe03a1..85abcfd3ffd 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4227,7 +4227,7 @@ Model.geoSearch = function(conditions, options, callback) {
  *     // it is in the schema's ref
  *
  * @param {Document|Array} docs Either a single document or array of documents to populate.
- * @param {Object} options A hash of key/val (path, options) used for population.
+ * @param {Object|String} options either the paths to populate or an object specifying all parameters
  * @param {string} [options.path=null] The path to populate.
  * @param {boolean} [options.retainNullValues=false] by default, Mongoose removes null and undefined values from populated arrays. Use this option to make `populate()` retain `null` and `undefined` array entries.
  * @param {boolean} [options.getters=false] if true, Mongoose will call any getters defined on the `localField`. By default, Mongoose gets the raw value of `localField`. For example, you would need to set this option to `true` if you wanted to [add a `lowercase` getter to your `localField`](/docs/schematypes.html#schematype-options).

From 227333e07dacb38ebcff3cd655dfea11da8140e5 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 22 Apr 2020 14:18:36 +0200
Subject: [PATCH 0729/2348] fix punctutaion

---
 lib/model.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 85abcfd3ffd..6d01acd5d78 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4227,10 +4227,10 @@ Model.geoSearch = function(conditions, options, callback) {
  *     // it is in the schema's ref
  *
  * @param {Document|Array} docs Either a single document or array of documents to populate.
- * @param {Object|String} options either the paths to populate or an object specifying all parameters
+ * @param {Object|String} options Either the paths to populate or an object specifying all parameters
  * @param {string} [options.path=null] The path to populate.
- * @param {boolean} [options.retainNullValues=false] by default, Mongoose removes null and undefined values from populated arrays. Use this option to make `populate()` retain `null` and `undefined` array entries.
- * @param {boolean} [options.getters=false] if true, Mongoose will call any getters defined on the `localField`. By default, Mongoose gets the raw value of `localField`. For example, you would need to set this option to `true` if you wanted to [add a `lowercase` getter to your `localField`](/docs/schematypes.html#schematype-options).
+ * @param {boolean} [options.retainNullValues=false] By default, Mongoose removes null and undefined values from populated arrays. Use this option to make `populate()` retain `null` and `undefined` array entries.
+ * @param {boolean} [options.getters=false] If true, Mongoose will call any getters defined on the `localField`. By default, Mongoose gets the raw value of `localField`. For example, you would need to set this option to `true` if you wanted to [add a `lowercase` getter to your `localField`](/docs/schematypes.html#schematype-options).
  * @param {boolean} [options.clone=false] When you do `BlogPost.find().populate('author')`, blog posts with the same author will share 1 copy of an `author` doc. Enable this option to make Mongoose clone populated docs before assigning them.
  * @param {Object|Function} [options.match=null] Add an additional filter to the populate query. Can be a filter object containing [MongoDB query syntax](https://docs.mongodb.com/manual/tutorial/query-documents/), or a function that returns a filter object.
  * @param {Boolean} [options.skipInvalidIds=false] By default, Mongoose throws a cast error if `localField` and `foreignField` schemas don't line up. If you enable this option, Mongoose will instead filter out any `localField` properties that cannot be casted to `foreignField`'s schema type.

From e0f554cf5a372289b04b31efdb55ab72d1666d66 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 02:49:44 +0200
Subject: [PATCH 0730/2348] Add boolean variable

---
 lib/cursor/AggregationCursor.js | 3 ++-
 lib/cursor/QueryCursor.js       | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 16bcdbbcd5c..9137a88e93b 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -87,7 +87,8 @@ AggregationCursor.prototype._read = function() {
         }
         setTimeout(function() {
           // on node >= 14 streams close automatically (gh-8834)
-          if (!_this.destroyed) {
+          const isNotClosedAutomatically = !_this.destroyed;
+          if (isNotClosedAutomatically) {
             _this.emit('close');
           }
         }, 0);
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index f20014eae87..4fd31c66dbc 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -89,7 +89,8 @@ QueryCursor.prototype._read = function() {
         }
         setTimeout(function() {
           // on node >= 14 streams close automatically (gh-8834)
-          if (!_this.destroyed) {
+          const isNotClosedAutomatically = !_this.destroyed;
+          if (isNotClosedAutomatically) {
             _this.emit('close');
           }
         }, 0);

From 242cb6a224bcdc2f3e82ed9f2bd0aa49d6e92a70 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 03:55:07 +0200
Subject: [PATCH 0731/2348] convert more loops to for-of

---
 lib/cast.js       | 6 ++++--
 lib/collection.js | 8 ++++----
 website.js        | 6 ++++--
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/lib/cast.js b/lib/cast.js
index 9fe01ba7283..7e229638f68 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -303,9 +303,11 @@ module.exports = function cast(schema, obj, options, context) {
         }
       } else if (Array.isArray(val) && ['Buffer', 'Array'].indexOf(schematype.instance) === -1) {
         const casted = [];
-        for (let valIndex = 0; valIndex < val.length; valIndex++) {
+        const valuesArray = val;
+
+        for (const _val of valuesArray) {
           casted.push(schematype.castForQueryWrapper({
-            val: val[valIndex],
+            val: _val,
             context: context
           }));
         }
diff --git a/lib/collection.js b/lib/collection.js
index ff024265219..b53709407f9 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -119,11 +119,11 @@ Collection.prototype.addQueue = function(name, args) {
  */
 
 Collection.prototype.doQueue = function() {
-  for (let i = 0, l = this.queue.length; i < l; i++) {
-    if (typeof this.queue[i][0] === 'function') {
-      this.queue[i][0].apply(this, this.queue[i][1]);
+  for (const method of this.queue) {
+    if (typeof method[0] === 'function') {
+      method[0].apply(this, method[1]);
     } else {
-      this[this.queue[i][0]].apply(this, this.queue[i][1]);
+      this[method[0]].apply(this, method[1]);
     }
   }
   this.queue = [];
diff --git a/website.js b/website.js
index b2bc4630993..0b616705160 100644
--- a/website.js
+++ b/website.js
@@ -42,8 +42,9 @@ function getVersion() {
 
 function getLatestLegacyVersion(startsWith) {
   const hist = fs.readFileSync('./History.md', 'utf8').replace(/\r/g, '\n').split('\n');
-  for (let i = 0; i < hist.length; ++i) {
-    const line = (hist[i] || '').trim();
+
+  for (const rawLine of hist) {
+    const line = (rawLine || '').trim();
     if (!line) {
       continue;
     }
@@ -52,6 +53,7 @@ function getLatestLegacyVersion(startsWith) {
       return match[1];
     }
   }
+
   throw new Error('no match found');
 }
 

From 5a899a7247492c54c155b8b63ac02bf816392de9 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 04:14:00 +0200
Subject: [PATCH 0732/2348] refactor: convert more loops to for-of

---
 lib/document.js | 48 +++++++++++++++++++++++++-----------------------
 lib/model.js    | 15 ++++++++-------
 2 files changed, 33 insertions(+), 30 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index e599a01b0d0..4eb3b29a14b 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -99,9 +99,9 @@ function Document(obj, fields, skipId, options) {
     this.$__.selected = fields;
   }
 
-  const required = schema.requiredPaths(true);
-  for (let i = 0; i < required.length; ++i) {
-    this.$__.activePaths.require(required[i]);
+  const requiredPaths = schema.requiredPaths(true);
+  for (const path of requiredPaths) {
+    this.$__.activePaths.require(path);
   }
 
   this.$__.emitter.setMaxListeners(0);
@@ -303,11 +303,13 @@ Document.prototype.$op;
 function $__hasIncludedChildren(fields) {
   const hasIncludedChildren = {};
   const keys = Object.keys(fields);
-  for (let j = 0; j < keys.length; ++j) {
-    const parts = keys[j].split('.');
+
+  for (const key of keys) {
+    const parts = key.split('.');
     const c = [];
-    for (let k = 0; k < parts.length; ++k) {
-      c.push(parts[k]);
+
+    for (const part of parts) {
+      c.push(part);
       hasIncludedChildren[c.join('.')] = 1;
     }
   }
@@ -581,6 +583,7 @@ function markArraySubdocsPopulated(doc, populated) {
       if (val == null) {
         continue;
       }
+
       if (val.isMongooseDocumentArray) {
         for (let j = 0; j < val.length; ++j) {
           val[j].populated(rest, item._docs[id] == null ? [] : item._docs[id][j], item);
@@ -2902,10 +2905,8 @@ function applyQueue(doc) {
   if (!q.length) {
     return;
   }
-  let pair;
 
-  for (let i = 0; i < q.length; ++i) {
-    pair = q[i];
+  for (const pair of q) {
     if (pair[0] !== 'pre' && pair[0] !== 'post' && pair[0] !== 'on') {
       doc[pair[0]].apply(doc, pair[1]);
     }
@@ -3552,8 +3553,8 @@ Document.prototype.populate = function populate() {
   if (args.length) {
     // use hash to remove duplicate paths
     const res = utils.populate.apply(null, args);
-    for (let i = 0; i < res.length; ++i) {
-      pop[res[i].path] = res[i];
+    for (const populateOptions of res) {
+      pop[populateOptions.path] = populateOptions;
     }
   }
 
@@ -3711,16 +3712,17 @@ Document.prototype.depopulate = function(path) {
   if (typeof path === 'string') {
     path = path.split(' ');
   }
+
   let populatedIds;
   const virtualKeys = this.$$populatedVirtuals ? Object.keys(this.$$populatedVirtuals) : [];
   const populated = get(this, '$__.populated', {});
 
   if (arguments.length === 0) {
     // Depopulate all
-    for (let i = 0; i < virtualKeys.length; i++) {
-      delete this.$$populatedVirtuals[virtualKeys[i]];
-      delete this._doc[virtualKeys[i]];
-      delete populated[virtualKeys[i]];
+    for (const virtualKey of virtualKeys) {
+      delete this.$$populatedVirtuals[virtualKey];
+      delete this._doc[virtualKey];
+      delete populated[virtualKey];
     }
 
     const keys = Object.keys(populated);
@@ -3736,15 +3738,15 @@ Document.prototype.depopulate = function(path) {
     return this;
   }
 
-  for (let i = 0; i < path.length; i++) {
-    populatedIds = this.populated(path[i]);
-    delete populated[path[i]];
+  for (const singlePath of path) {
+    populatedIds = this.populated(singlePath);
+    delete populated[singlePath];
 
-    if (virtualKeys.indexOf(path[i]) !== -1) {
-      delete this.$$populatedVirtuals[path[i]];
-      delete this._doc[path[i]];
+    if (virtualKeys.indexOf(singlePath) !== -1) {
+      delete this.$$populatedVirtuals[singlePath];
+      delete this._doc[singlePath];
     } else if (populatedIds) {
-      this.$set(path[i], populatedIds);
+      this.$set(singlePath, populatedIds);
     }
   }
   return this;
diff --git a/lib/model.js b/lib/model.js
index 21e56c74d83..0caa9973e8e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3368,10 +3368,12 @@ Model.$__insertMany = function(arr, options, callback) {
         callback(error, null);
         return;
       }
-      for (let i = 0; i < docAttributes.length; ++i) {
-        docAttributes[i].$__reset();
-        _setIsNew(docAttributes[i], false);
+
+      for (const attribute of docAttributes) {
+        attribute.$__reset();
+        _setIsNew(attribute, false);
       }
+
       if (rawResult) {
         if (ordered === false) {
           // Decorate with mongoose validation errors in case of unordered,
@@ -4273,16 +4275,15 @@ Model.populate = function(docs, paths, callback) {
  */
 
 function _populate(model, docs, paths, cache, callback) {
-  const length = paths.length;
   let pending = paths.length;
 
-  if (length === 0) {
+  if (paths.length === 0) {
     return callback(null, docs);
   }
 
   // each path has its own query options and must be executed separately
-  for (let i = 0; i < length; ++i) {
-    populate(model, docs, paths[i], next);
+  for (const path of paths) {
+    populate(model, docs, path, next);
   }
 
   function next(err) {

From 87b3f0421372fc447220bb9d880047c9dcec56fa Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 04:31:10 +0200
Subject: [PATCH 0733/2348] refactor: convert more loops to for-of

---
 lib/model.js        |  5 ++---
 lib/query.js        | 45 ++++++++++++++++++++-------------------------
 lib/queryhelpers.js | 20 ++++++++++----------
 lib/schema.js       | 17 +++++++++--------
 lib/schematype.js   | 10 +++++-----
 5 files changed, 46 insertions(+), 51 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 0caa9973e8e..2f558ff9a69 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4515,9 +4515,8 @@ function _assign(model, vals, mod, assignmentOpts) {
       _val = utils.getValue(foreignField, val);
       if (Array.isArray(_val)) {
         _val = utils.array.flatten(_val);
-        const _valLength = _val.length;
-        for (let j = 0; j < _valLength; ++j) {
-          let __val = _val[j];
+
+        for (let __val of _val) {
           if (__val instanceof Document) {
             __val = __val._id;
           }
diff --git a/lib/query.js b/lib/query.js
index a355e2b8a3d..de4195879ee 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -70,9 +70,8 @@ function Query(conditions, options, model, collection) {
   // this is the case where we have a CustomQuery, we need to check if we got
   // options passed in, and if we did, merge them in
   const keys = Object.keys(options);
-  for (let i = 0; i < keys.length; ++i) {
-    const k = keys[i];
-    this._mongooseOptions[k] = options[k];
+  for (const key of keys) {
+    this._mongooseOptions[key] = options[key];
   }
 
   if (collection) {
@@ -4604,14 +4603,14 @@ Query.prototype.populate = function() {
     const readConcern = this.options.readConcern;
     const readPref = this.options.readPreference;
 
-    for (let i = 0; i < res.length; ++i) {
-      if (readConcern != null && get(res[i], 'options.readConcern') == null) {
-        res[i].options = res[i].options || {};
-        res[i].options.readConcern = readConcern;
+    for (const populateOptions of res) {
+      if (readConcern != null && get(populateOptions, 'options.readConcern') == null) {
+        populateOptions.options = populateOptions.options || {};
+        populateOptions.options.readConcern = readConcern;
       }
-      if (readPref != null && get(res[i], 'options.readPreference') == null) {
-        res[i].options = res[i].options || {};
-        res[i].options.readPreference = readPref;
+      if (readPref != null && get(populateOptions, 'options.readPreference') == null) {
+        populateOptions.options = populateOptions.options || {};
+        populateOptions.options.readPreference = readPref;
       }
     }
   }
@@ -4620,10 +4619,10 @@ Query.prototype.populate = function() {
 
   if (opts.lean != null) {
     const lean = opts.lean;
-    for (let i = 0; i < res.length; ++i) {
-      if (get(res[i], 'options.lean') == null) {
-        res[i].options = res[i].options || {};
-        res[i].options.lean = lean;
+    for (const populateOptions of res) {
+      if (get(populateOptions, 'options.lean') == null) {
+        populateOptions.options = populateOptions.options || {};
+        populateOptions.options.lean = lean;
       }
     }
   }
@@ -4634,12 +4633,13 @@ Query.prototype.populate = function() {
 
   const pop = opts.populate;
 
-  for (let i = 0; i < res.length; ++i) {
-    const path = res[i].path;
-    if (pop[path] && pop[path].populate && res[i].populate) {
-      res[i].populate = pop[path].populate.concat(res[i].populate);
+  for (const populateOptions of res) {
+    const path = populateOptions.path;
+    if (pop[path] && pop[path].populate && populateOptions.populate) {
+      populateOptions.populate = pop[path].populate.concat(populateOptions.populate);
     }
-    pop[res[i].path] = res[i];
+
+    pop[populateOptions.path] = populateOptions;
   }
 
   return this;
@@ -5326,12 +5326,7 @@ Query.prototype.selectedExclusively = function selectedExclusively() {
   }
 
   const keys = Object.keys(this._fields);
-  if (keys.length === 0) {
-    return false;
-  }
-
-  for (let i = 0; i < keys.length; ++i) {
-    const key = keys[i];
+  for (const key of keys) {
     if (key === '_id') {
       continue;
     }
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 343c3b175c4..6ed12c69e8f 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -174,8 +174,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
     // check for parent exclusions
     const pieces = path.split('.');
     let cur = '';
-    for (let i = 0; i < pieces.length; ++i) {
-      cur += cur.length ? '.' + pieces[i] : pieces[i];
+    for (const piece of pieces) {
+      cur += cur.length ? '.' + piece : piece;
       if (excluded.indexOf(cur) !== -1) {
         return;
       }
@@ -186,8 +186,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
     // project out everything else under the parent path
     if (!exclude && get(type, 'options.$skipDiscriminatorCheck', false)) {
       let cur = '';
-      for (let i = 0; i < pieces.length; ++i) {
-        cur += (cur.length === 0 ? '' : '.') + pieces[i];
+      for (const piece of pieces) {
+        cur += (cur.length === 0 ? '' : '.') + piece;
         const projection = get(fields, cur, false);
         if (projection && typeof projection !== 'object') {
           return;
@@ -203,8 +203,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
 
   switch (exclude) {
     case true:
-      for (let i = 0; i < excluded.length; ++i) {
-        fields[excluded[i]] = 0;
+      for (const fieldName of excluded) {
+        fields[fieldName] = 0;
       }
       break;
     case false:
@@ -214,8 +214,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
           schema.paths['_id'].options.select === false) {
         fields._id = 0;
       }
-      for (let i = 0; i < selected.length; ++i) {
-        fields[selected[i]] = 1;
+      for (const fieldName of selected) {
+        fields[fieldName] = 1;
       }
       break;
     case undefined:
@@ -231,8 +231,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
 
       // user didn't specify fields, implies returning all fields.
       // only need to apply excluded fields and delete any plus paths
-      for (let i = 0; i < excluded.length; ++i) {
-        fields[excluded[i]] = 0;
+      for (const fieldName of excluded) {
+        fields[fieldName] = 0;
       }
       break;
   }
diff --git a/lib/schema.js b/lib/schema.js
index 16e5dd0de33..86c0d1eaf3a 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -460,8 +460,7 @@ Schema.prototype.add = function add(obj, prefix) {
   prefix = prefix || '';
   const keys = Object.keys(obj);
 
-  for (let i = 0; i < keys.length; ++i) {
-    const key = keys[i];
+  for (const key of keys) {
     const fullPath = prefix + key;
 
     if (obj[key] == null) {
@@ -1486,10 +1485,9 @@ Schema.prototype.plugin = function(fn, opts) {
       'got "' + (typeof fn) + '"');
   }
 
-  if (opts &&
-      opts.deduplicate) {
-    for (let i = 0; i < this.plugins.length; ++i) {
-      if (this.plugins[i].fn === fn) {
+  if (opts && opts.deduplicate) {
+    for (const plugin of this.plugins) {
+      if (plugin.fn === fn) {
         return this;
       }
     }
@@ -1908,10 +1906,13 @@ Schema.prototype.remove = function(path) {
 function _deletePath(schema, name) {
   const pieces = name.split('.');
   const last = pieces.pop();
+
   let branch = schema.tree;
-  for (let i = 0; i < pieces.length; ++i) {
-    branch = branch[pieces[i]];
+
+  for (const piece of pieces) {
+    branch = branch[piece];
   }
+
   delete branch[last];
 }
 
diff --git a/lib/schematype.js b/lib/schematype.js
index c1e197b4374..5b22356b7f4 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -972,17 +972,17 @@ SchemaType.prototype.getDefault = function(scope, init) {
 SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
   let v = value;
   const setters = this.setters;
-  let len = setters.length;
   const caster = this.caster;
 
-  while (len--) {
-    v = setters[len].call(scope, v, this);
+  for (const setter of setters) {
+    v = setter.call(scope, v, this);
   }
 
   if (Array.isArray(v) && caster && caster.setters) {
     const newVal = [];
-    for (let i = 0; i < v.length; i++) {
-      newVal.push(caster.applySetters(v[i], scope, init, priorVal));
+
+    for (const value of v) {
+      newVal.push(caster.applySetters(value, scope, init, priorVal));
     }
     v = newVal;
   }

From 24e59af10b46cf5aef45573b85db1e2104df976a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 04:56:36 +0200
Subject: [PATCH 0734/2348] refactor: convert more loops to for-of

---
 lib/error/validator.js | 5 +++--
 lib/helpers/clone.js   | 6 ++++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/error/validator.js b/lib/error/validator.js
index d07100c4182..2464581faa3 100644
--- a/lib/error/validator.js
+++ b/lib/error/validator.js
@@ -63,14 +63,15 @@ ValidatorError.prototype.formatMessage = function(msg, properties) {
   if (typeof msg === 'function') {
     return msg(properties);
   }
+
   const propertyNames = Object.keys(properties);
-  for (let i = 0; i < propertyNames.length; ++i) {
-    const propertyName = propertyNames[i];
+  for (const propertyName of propertyNames) {
     if (propertyName === 'message') {
       continue;
     }
     msg = msg.replace('{' + propertyName.toUpperCase() + '}', properties[propertyName]);
   }
+
   return msg;
 };
 
diff --git a/lib/helpers/clone.js b/lib/helpers/clone.js
index c0ed1364337..1d53776f368 100644
--- a/lib/helpers/clone.js
+++ b/lib/helpers/clone.js
@@ -128,8 +128,10 @@ function cloneObject(obj, options, isArrayChild) {
 
 function cloneArray(arr, options) {
   const ret = [];
-  for (let i = 0, l = arr.length; i < l; i++) {
-    ret.push(clone(arr[i], options, true));
+
+  for (const item of arr) {
+    ret.push(clone(item, options, true));
   }
+
   return ret;
 }
\ No newline at end of file

From 1300844d3af68e433e256312e90f113e259cc396 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 04:58:53 +0200
Subject: [PATCH 0735/2348] trigger travis build

---
 lib/helpers/updateValidators.js |  3 +--
 lib/utils.js                    | 34 ++++++++++++++++-----------------
 2 files changed, 18 insertions(+), 19 deletions(-)

diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index bd2718d75de..fa47520f77c 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -171,8 +171,7 @@ module.exports = function(query, schema, castedDoc, options, callback) {
   }
 
   const arrayUpdates = Object.keys(arrayAtomicUpdates);
-  const numArrayUpdates = arrayUpdates.length;
-  for (i = 0; i < numArrayUpdates; ++i) {
+  for (i = 0; i < arrayUpdates.length; ++i) {
     (function(i) {
       let schemaPath = schema._getSchema(arrayUpdates[i]);
       if (schemaPath && schemaPath.$isMongooseDocumentArray) {
diff --git a/lib/utils.js b/lib/utils.js
index b0a374982a7..23411ee2275 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -301,8 +301,8 @@ exports.toObject = function toObject(obj) {
   if (Array.isArray(obj)) {
     ret = [];
 
-    for (let i = 0, len = obj.length; i < len; ++i) {
-      ret.push(toObject(obj[i]));
+    for (const doc of obj) {
+      ret.push(toObject(doc));
     }
 
     return ret;
@@ -557,8 +557,8 @@ function _populateObj(obj) {
     obj.options = exports.clone(obj.options);
   }
 
-  for (let i = 0; i < paths.length; ++i) {
-    ret.push(new PopulateOptions(Object.assign({}, obj, { path: paths[i] })));
+  for (const path of paths) {
+    ret.push(new PopulateOptions(Object.assign({}, obj, { path: path })));
   }
 
   return ret;
@@ -737,22 +737,22 @@ exports.array.unique = function(arr) {
   const primitives = {};
   const ids = {};
   const ret = [];
-  const length = arr.length;
-  for (let i = 0; i < length; ++i) {
-    if (typeof arr[i] === 'number' || typeof arr[i] === 'string' || arr[i] == null) {
-      if (primitives[arr[i]]) {
+
+  for (const item of arr) {
+    if (typeof item === 'number' || typeof item === 'string' || item == null) {
+      if (primitives[item]) {
         continue;
       }
-      ret.push(arr[i]);
-      primitives[arr[i]] = true;
-    } else if (arr[i] instanceof ObjectId) {
-      if (ids[arr[i].toString()]) {
+      ret.push(item);
+      primitives[item] = true;
+    } else if (item instanceof ObjectId) {
+      if (ids[item.toString()]) {
         continue;
       }
-      ret.push(arr[i]);
-      ids[arr[i].toString()] = true;
+      ret.push(item);
+      ids[item.toString()] = true;
     } else {
-      ret.push(arr[i]);
+      ret.push(item);
     }
   }
 
@@ -873,8 +873,8 @@ exports.mergeClone = function(to, fromObj) {
  */
 
 exports.each = function(arr, fn) {
-  for (let i = 0; i < arr.length; ++i) {
-    fn(arr[i]);
+  for (const item of arr) {
+    fn(item);
   }
 };
 

From dfe94c63367a3ea6300915a24b6e2ebbb1e872c6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 05:10:43 +0200
Subject: [PATCH 0736/2348] fix failing test

---
 lib/schematype.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index be7c9cf7716..dba11cc145e 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -980,10 +980,11 @@ SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
   const setters = this.setters;
   const caster = this.caster;
 
-  for (const setter of setters) {
+  for (const setter of utils.clone(setters).reverse()) {
     v = setter.call(scope, v, this);
   }
 
+
   if (Array.isArray(v) && caster && caster.setters) {
     const newVal = [];
 
@@ -993,6 +994,7 @@ SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
     v = newVal;
   }
 
+
   return v;
 };
 

From 92f1845d4071066ef001d597ff3c4034695308ad Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 05:18:10 +0200
Subject: [PATCH 0737/2348] refactor: use || instead of != null in loop, and
 use for-of

---
 lib/queryhelpers.js | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 4e92aa13f98..13d6ff83590 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -163,9 +163,8 @@ exports.applyPaths = function applyPaths(fields, schema) {
         fields._id = 0;
       }
 
-      for (let i = 0; i < selected.length; ++i) {
-        const fieldSelectionValue = fields[selected[i]] != null ? fields[selected[i]] : 1;
-        fields[selected[i]] = fieldSelectionValue;
+      for (const fieldName of selected) {
+        fields[fieldName] = fields[fieldName] || 1;
       }
       break;
     case undefined:

From bc8b91f1eaa1d0b895aef93c4d9f615e4e85b7d1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 05:29:59 +0200
Subject: [PATCH 0738/2348] refactor: remove duplicated code from
 updateValidators, use for-of, remove iife

---
 lib/helpers/updateValidators.js | 61 +++++++++++++++------------------
 1 file changed, 28 insertions(+), 33 deletions(-)

diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index fa47520f77c..dbc42a97134 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -171,43 +171,27 @@ module.exports = function(query, schema, castedDoc, options, callback) {
   }
 
   const arrayUpdates = Object.keys(arrayAtomicUpdates);
-  for (i = 0; i < arrayUpdates.length; ++i) {
-    (function(i) {
-      let schemaPath = schema._getSchema(arrayUpdates[i]);
-      if (schemaPath && schemaPath.$isMongooseDocumentArray) {
+  for (const arrayUpdate of arrayUpdates) {
+    let schemaPath = schema._getSchema(arrayUpdate);
+    if (schemaPath && schemaPath.$isMongooseDocumentArray) {
+      validatorsToExecute.push(function(callback) {
+        schemaPath.doValidate(
+          arrayAtomicUpdates[arrayUpdate],
+          getValidationCallback(arrayUpdate, validationErrors, callback),
+          options && options.context === 'query' ? query : null);
+      });
+    } else {
+      schemaPath = schema._getSchema(arrayUpdate + '.0');
+      for (const atomicUpdate of arrayAtomicUpdates[arrayUpdate]) {
         validatorsToExecute.push(function(callback) {
           schemaPath.doValidate(
-            arrayAtomicUpdates[arrayUpdates[i]],
-            function(err) {
-              if (err) {
-                err.path = arrayUpdates[i];
-                validationErrors.push(err);
-              }
-              callback(null);
-            },
-            options && options.context === 'query' ? query : null);
+            atomicUpdate,
+            getValidationCallback(arrayUpdate, validationErrors, callback),
+            options && options.context === 'query' ? query : null,
+            { updateValidator: true });
         });
-      } else {
-        schemaPath = schema._getSchema(arrayUpdates[i] + '.0');
-        for (let j = 0; j < arrayAtomicUpdates[arrayUpdates[i]].length; ++j) {
-          (function(j) {
-            validatorsToExecute.push(function(callback) {
-              schemaPath.doValidate(
-                arrayAtomicUpdates[arrayUpdates[i]][j],
-                function(err) {
-                  if (err) {
-                    err.path = arrayUpdates[i];
-                    validationErrors.push(err);
-                  }
-                  callback(null);
-                },
-                options && options.context === 'query' ? query : null,
-                { updateValidator: true });
-            });
-          })(j);
-        }
       }
-    })(i);
+    }
   }
 
   if (callback != null) {
@@ -250,4 +234,15 @@ module.exports = function(query, schema, castedDoc, options, callback) {
     }
     callback(null);
   }
+
+  function getValidationCallback(arrayUpdate, validationErrors, callback) {
+    return function(err) {
+      if (err) {
+        err.path = arrayUpdate;
+        validationErrors.push(err);
+      }
+      callback(null);
+    };
+  }
 };
+

From ec04cf11ed60026109e57acb0eab0aaa692cd8b8 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 05:42:46 +0200
Subject: [PATCH 0739/2348] refactor: convert more loops to for-of

---
 lib/helpers/model/applyHooks.js               |  6 +++---
 lib/helpers/model/discriminator.js            | 21 +++++++++----------
 .../populate/getModelsMapForPopulate.js       | 15 ++++++-------
 lib/helpers/populate/getSchemaTypes.js        |  4 ++--
 lib/helpers/updateValidators.js               |  6 ++++--
 5 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index 3dbca033f0c..de45f96a322 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -59,9 +59,9 @@ function applyHooks(model, schema, options) {
     applyHooks(childModel, type.schema, options);
     if (childModel.discriminators != null) {
       const keys = Object.keys(childModel.discriminators);
-      for (let j = 0; j < keys.length; ++j) {
-        applyHooks(childModel.discriminators[keys[j]],
-          childModel.discriminators[keys[j]].schema, options);
+      for (const key of keys) {
+        applyHooks(childModel.discriminators[key],
+          childModel.discriminators[key].schema, options);
       }
     }
   }
diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index 51c7cc0b7aa..d689e1c6c1b 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -80,9 +80,10 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     // See gh-6076
     const baseSchemaPaths = Object.keys(baseSchema.paths);
     const conflictingPaths = [];
-    for (let i = 0; i < baseSchemaPaths.length; ++i) {
-      if (schema.nested[baseSchemaPaths[i]]) {
-        conflictingPaths.push(baseSchemaPaths[i]);
+
+    for (const path of baseSchemaPaths) {
+      if (schema.nested[path]) {
+        conflictingPaths.push(path);
       }
     }
 
@@ -95,8 +96,8 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     });
 
     // Clean up conflicting paths _after_ merging re: gh-6076
-    for (let i = 0; i < conflictingPaths.length; ++i) {
-      delete schema.paths[conflictingPaths[i]];
+    for (const conflictingPath of conflictingPaths) {
+      delete schema.paths[conflictingPath];
     }
 
     // Rebuild schema models because schemas may have been merged re: #7884
@@ -134,18 +135,16 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     const keys = Object.keys(schema.options);
     schema.options.discriminatorKey = baseSchema.options.discriminatorKey;
 
-    for (let i = 0; i < keys.length; ++i) {
-      const _key = keys[i];
+    for (const _key of keys) {
       if (!CUSTOMIZABLE_DISCRIMINATOR_OPTIONS[_key]) {
         if (!utils.deepEqual(schema.options[_key], baseSchema.options[_key])) {
           throw new Error('Can\'t customize discriminator option ' + _key +
-              ' (can only modify ' +
-              Object.keys(CUSTOMIZABLE_DISCRIMINATOR_OPTIONS).join(', ') +
-              ')');
+          ' (can only modify ' +
+          Object.keys(CUSTOMIZABLE_DISCRIMINATOR_OPTIONS).join(', ') +
+          ')');
         }
       }
     }
-
     schema.options = utils.clone(baseSchema.options);
     if (toJSON) schema.options.toJSON = toJSON;
     if (toObject) schema.options.toObject = toObject;
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 4edad56f164..c375baca0d9 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -53,11 +53,12 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     let normalizedRefPath = _firstWithRefPath ? get(_firstWithRefPath, 'options.refPath', null) : null;
 
     if (Array.isArray(schema)) {
-      for (let j = 0; j < schema.length; ++j) {
+      const schemasArray = schema;
+      for (const _schema of schemasArray) {
         let _modelNames;
         let res;
         try {
-          res = _getModelNames(doc, schema[j]);
+          res = _getModelNames(doc, _schema);
           _modelNames = res.modelNames;
           isRefPath = isRefPath || res.isRefPath;
           normalizedRefPath = normalizeRefPath(normalizedRefPath, doc, options.path) ||
@@ -73,9 +74,9 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           continue;
         }
         modelNames = modelNames || [];
-        for (let x = 0; x < _modelNames.length; ++x) {
-          if (modelNames.indexOf(_modelNames[x]) === -1) {
-            modelNames.push(_modelNames[x]);
+        for (const modelName of _modelNames) {
+          if (modelNames.indexOf(modelName) === -1) {
+            modelNames.push(modelName);
           }
         }
       }
@@ -216,8 +217,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     if (isRefPath && normalizedRefPath != null) {
       const pieces = normalizedRefPath.split('.');
       let cur = '';
-      for (let i = 0; i < pieces.length; ++i) {
-        cur = cur + (cur.length === 0 ? '' : '.') + pieces[i];
+      for (const piece of pieces) {
+        cur = cur + (cur.length === 0 ? '' : '.') + piece;
         const schematype = modelSchema.path(cur);
         if (schematype != null &&
             schematype.$isMongooseArray &&
diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index 8db0079edbf..15660df1f78 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -88,10 +88,10 @@ module.exports = function getSchemaTypes(schema, doc, path) {
 
           if (schemas != null && schemas.length > 0) {
             ret = [];
-            for (let i = 0; i < schemas.length; ++i) {
+            for (const schema of schemas) {
               const _ret = search(
                 parts.slice(p),
-                schemas[i],
+                schema,
                 subdoc ? mpath.get(trypath, subdoc) : null,
                 nestedPath.concat(parts.slice(0, p))
               );
diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index dbc42a97134..b6ecaacf84c 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -227,9 +227,11 @@ module.exports = function(query, schema, castedDoc, options, callback) {
   function _done(callback) {
     if (validationErrors.length) {
       const err = new ValidationError(null);
-      for (let i = 0; i < validationErrors.length; ++i) {
-        err.addError(validationErrors[i].path, validationErrors[i]);
+
+      for (const validationError of validationErrors) {
+        err.addError(validationError.path, validationError);
       }
+
       return callback(err);
     }
     callback(null);

From a52b920ff45d282ae72b2004c192c68e02ba1d50 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 05:55:38 +0200
Subject: [PATCH 0740/2348] refactor: convert more loops to for-of

---
 lib/helpers/query/selectPopulatedFields.js | 16 ++++++++--------
 lib/helpers/schema/applyPlugins.js         |  7 +++----
 lib/helpers/schema/getIndexes.js           |  4 +---
 lib/schema/array.js                        |  4 ++--
 lib/schema/string.js                       |  6 +++---
 lib/types/core_array.js                    |  4 ++--
 lib/types/documentarray.js                 | 13 +++++++------
 lib/types/map.js                           |  6 ++++--
 test/document.test.js                      |  6 +++---
 test/model.geosearch.test.js               |  8 ++++----
 10 files changed, 37 insertions(+), 37 deletions(-)

diff --git a/lib/helpers/query/selectPopulatedFields.js b/lib/helpers/query/selectPopulatedFields.js
index 15f7e99eaf0..0653f18d71d 100644
--- a/lib/helpers/query/selectPopulatedFields.js
+++ b/lib/helpers/query/selectPopulatedFields.js
@@ -11,17 +11,17 @@ module.exports = function selectPopulatedFields(query) {
     const paths = Object.keys(opts.populate);
     const userProvidedFields = query._userProvidedFields || {};
     if (query.selectedInclusively()) {
-      for (let i = 0; i < paths.length; ++i) {
-        if (!isPathInFields(userProvidedFields, paths[i])) {
-          query.select(paths[i]);
-        } else if (userProvidedFields[paths[i]] === 0) {
-          delete query._fields[paths[i]];
+      for (const path of paths) {
+        if (!isPathInFields(userProvidedFields, path)) {
+          query.select(path);
+        } else if (userProvidedFields[path] === 0) {
+          delete query._fields[path];
         }
       }
     } else if (query.selectedExclusively()) {
-      for (let i = 0; i < paths.length; ++i) {
-        if (userProvidedFields[paths[i]] == null) {
-          delete query._fields[paths[i]];
+      for (const path of paths) {
+        if (userProvidedFields[path] == null) {
+          delete query._fields[path];
         }
       }
     }
diff --git a/lib/helpers/schema/applyPlugins.js b/lib/helpers/schema/applyPlugins.js
index 1bc7727b4fe..f1daf4012e8 100644
--- a/lib/helpers/schema/applyPlugins.js
+++ b/lib/helpers/schema/applyPlugins.js
@@ -7,8 +7,8 @@ module.exports = function applyPlugins(schema, plugins, options, cacheKey) {
   schema[cacheKey] = true;
 
   if (!options || !options.skipTopLevel) {
-    for (let i = 0; i < plugins.length; ++i) {
-      schema.plugin(plugins[i][0], plugins[i][1]);
+    for (const plugin of plugins) {
+      schema.plugin(plugin[0], plugin[1]);
     }
   }
 
@@ -35,8 +35,7 @@ module.exports = function applyPlugins(schema, plugins, options, cacheKey) {
   const applyPluginsToDiscriminators = options.applyPluginsToDiscriminators;
 
   const keys = Object.keys(discriminators);
-  for (let i = 0; i < keys.length; ++i) {
-    const discriminatorKey = keys[i];
+  for (const discriminatorKey of keys) {
     const discriminatorSchema = discriminators[discriminatorKey];
 
     applyPlugins(discriminatorSchema, plugins,
diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index bb3399966e8..cc6db9e9d6b 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -24,10 +24,8 @@ module.exports = function getIndexes(schema) {
 
     prefix = prefix || '';
     const keys = Object.keys(schema.paths);
-    const length = keys.length;
 
-    for (let i = 0; i < length; ++i) {
-      const key = keys[i];
+    for (const key of keys) {
       const path = schema.paths[key];
       if (baseSchema != null && baseSchema.paths[key]) {
         // If looking at an embedded discriminator schema, don't look at paths
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 7831d0bf67f..3986bddc559 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -534,8 +534,8 @@ handle.$or = handle.$and = function(val) {
   }
 
   const ret = [];
-  for (let i = 0; i < val.length; ++i) {
-    ret.push(cast(this.casterConstructor.schema, val[i]));
+  for (const obj of val) {
+    ret.push(cast(this.casterConstructor.schema, obj));
   }
 
   return ret;
diff --git a/lib/schema/string.js b/lib/schema/string.js
index e0771bec065..68906da81dc 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -224,9 +224,9 @@ SchemaString.prototype.enum = function() {
     errorMessage = MongooseError.messages.String.enum;
   }
 
-  for (let i = 0; i < values.length; i++) {
-    if (undefined !== values[i]) {
-      this.enumValues.push(this.cast(values[i]));
+  for (const value of values) {
+    if (value !== undefined) {
+      this.enumValues.push(this.cast(value));
     }
   }
 
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index a48bc409e4a..b6632359daa 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -911,8 +911,8 @@ function _isAllSubdocs(docs, ref) {
   if (!ref) {
     return false;
   }
-  for (let i = 0; i < docs.length; ++i) {
-    const arg = docs[i];
+
+  for (const arg of docs) {
     if (arg == null) {
       return false;
     }
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 2ad3a457687..b5ebbeb8ac0 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -135,25 +135,26 @@ class CoreDocumentArray extends CoreMongooseArray {
       casted = null;
     }
 
-    for (let i = 0, l = this.length; i < l; i++) {
-      if (!this[i]) {
+    for (const val of this) {
+      if (!val) {
         continue;
       }
-      _id = this[i].get('_id');
+
+      _id = val.get('_id');
 
       if (_id === null || typeof _id === 'undefined') {
         continue;
       } else if (_id instanceof Document) {
         sid || (sid = String(id));
         if (sid == _id._id) {
-          return this[i];
+          return val;
         }
       } else if (!(id instanceof ObjectId) && !(_id instanceof ObjectId)) {
         if (utils.deepEqual(id, _id)) {
-          return this[i];
+          return val;
         }
       } else if (casted == _id) {
-        return this[i];
+        return val;
       }
     }
 
diff --git a/lib/types/map.js b/lib/types/map.js
index bebd8db8567..73c926930fc 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -138,9 +138,11 @@ class MongooseMap extends Map {
     if (!this.$__deferred) {
       return;
     }
-    for (let i = 0; i < this.$__deferred.length; ++i) {
-      this.set(this.$__deferred[i].key, this.$__deferred[i].value);
+
+    for (const keyValueObject of this.$__deferred) {
+      this.set(keyValueObject.key, keyValueObject.value);
     }
+
     this.$__deferred = null;
   }
 }
diff --git a/test/document.test.js b/test/document.test.js
index 4e573e705cf..060fc092dce 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -6339,9 +6339,9 @@ describe('document', function() {
         name: {
           type: String,
           set: function(v) {
-            const sp = v.split(' ');
-            for (let i = 0; i < sp.length; ++i) {
-              this.keywords.push(sp[i]);
+            const splitStrings = v.split(' ');
+            for (const keyword of splitStrings) {
+              this.keywords.push(keyword);
             }
             return v;
           }
diff --git a/test/model.geosearch.test.js b/test/model.geosearch.test.js
index ab7ba9944b5..55e1e002713 100644
--- a/test/model.geosearch.test.js
+++ b/test/model.geosearch.test.js
@@ -43,8 +43,8 @@ describe('model', function() {
         geos[3] = new Geo({ pos: [1, -1], type: 'house' });
         let count = geos.length;
 
-        for (let i = 0; i < geos.length; i++) {
-          geos[i].save(function(err) {
+        for (const geo of geos) {
+          geo.save(function(err) {
             assert.ifError(err);
             --count || next();
           });
@@ -84,8 +84,8 @@ describe('model', function() {
         geos[3] = new Geo({ pos: [1, -1], type: 'house' });
         let count = geos.length;
 
-        for (let i = 0; i < geos.length; i++) {
-          geos[i].save(function(err) {
+        for (const geo of geos) {
+          geo.save(function(err) {
             assert.ifError(err);
             --count || next();
           });

From 68ece103d61528d3e676eb0f50d85765822c679d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 06:01:09 +0200
Subject: [PATCH 0741/2348] refactor: convert last loop to for-of

---
 test/types.number.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/types.number.test.js b/test/types.number.test.js
index 27b3114f89f..34afe3bb055 100644
--- a/test/types.number.test.js
+++ b/test/types.number.test.js
@@ -68,8 +68,8 @@ describe('types.number', function() {
     const items = [1, '2', '0', null, '', new String('47'), new Number(5), Number(47), Number('09'), 0x12];
     let err;
     try {
-      for (let i = 0, len = items.length; i < len; ++i) {
-        n.cast(items[i]);
+      for (const item of items) {
+        n.cast(item);
       }
     } catch (e) {
       err = e;

From bbf0d14ebee18a72141c6dce3ed2edc15752247f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 06:29:31 +0200
Subject: [PATCH 0742/2348] test: repro #8839

---
 test/document.populate.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index 654aa7f93e5..3873320cee1 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -999,4 +999,28 @@ describe('document.populate', function() {
       assert.ok(finalDoc.i.populated('g'));
     });
   });
+
+  it('doc.execPopulate(options) is a shorthand for doc.populate(options).execPopulate(...) (gh-8839)', function() {
+    const userSchema = new Schema({ name: String });
+    const User = db.model('Test1', userSchema);
+
+    const postSchema = new Schema({
+      user: { type: mongoose.ObjectId, ref: 'Test1' },
+      title: String
+    });
+
+    const Post = db.model('Test2', postSchema);
+
+    return co(function*() {
+      const user = yield User.create({ name: 'val' });
+
+      yield Post.create({ title: 'test1', user: user });
+
+      const post = yield Post.findOne();
+
+      yield post.execPopulate({ path: 'user' });
+
+      assert.equal(post.user.name, 'val');
+    });
+  });
 });

From a3aa376fd73c7d70fe0538b010e3fe73f8c8d347 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 06:38:48 +0200
Subject: [PATCH 0743/2348] make doc.execPopulate(options) a shorthand for
 doc.populate(options).execPopulate()

---
 benchmarks/create.js |  6 +++---
 lib/document.js      | 22 ++++++++++++++++++----
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/benchmarks/create.js b/benchmarks/create.js
index ccccdd95daf..3c69c0228c3 100644
--- a/benchmarks/create.js
+++ b/benchmarks/create.js
@@ -22,11 +22,11 @@ let Board = new Schema({
   checklists: {type: [Checklist]}
 });
 
-// var start1 = new Date();
+// const start1 = new Date();
 Board = mongoose.model('Board', Board);
-// var Cl = mongoose.model('Checklist', Checklist);
+// const Cl = mongoose.model('Checklist', Checklist);
 const doc = JSON.parse(fs.readFileSync(__dirname + '/bigboard.json'));
-// var time1 = (new Date - start1);
+// const time1 = (new Date - start1);
 // console.error('reading from disk and parsing JSON took %d ms', time1);
 
 const start2 = new Date();
diff --git a/lib/document.js b/lib/document.js
index d0809fa24dd..fd2f21974cd 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1832,7 +1832,7 @@ Document.prototype.isModified = function(paths, modifiedPaths) {
  * ####Example
  *
  *     MyModel = mongoose.model('test', { name: { type: String, default: 'Val '} });
- *     var m = new MyModel();
+ *     const m = new MyModel();
  *     m.$isDefault('name'); // true
  *
  * @memberOf Document
@@ -2429,7 +2429,7 @@ function _handlePathsToValidate(paths, pathsToValidate) {
  *
  * ####Example:
  *
- *     var err = doc.validateSync();
+ *     const err = doc.validateSync();
  *     if (err) {
  *       handleError(err);
  *     } else {
@@ -3155,7 +3155,7 @@ Document.prototype.$toObject = function(options, json) {
  *       return ret;
  *     }
  *
- *     var doc = new Doc({ _id: 'anId', secret: 47, name: 'Wreck-it Ralph' });
+ *     const doc = new Doc({ _id: 'anId', secret: 47, name: 'Wreck-it Ralph' });
  *     doc.toObject();                                        // { secret: 47, name: 'Wreck-it Ralph' }
  *     doc.toObject({ hide: 'secret _id', transform: false });// { _id: 'anId', secret: 47, name: 'Wreck-it Ralph' }
  *     doc.toObject({ hide: 'secret _id', transform: true }); // { name: 'Wreck-it Ralph' }
@@ -3598,7 +3598,7 @@ Document.prototype.populate = function populate() {
  *
  * ####Example:
  *
- *     var promise = doc.
+ *     const promise = doc.
  *       populate('company').
  *       populate({
  *         path: 'notes',
@@ -3612,6 +3612,15 @@ Document.prototype.populate = function populate() {
  *     // summary
  *     doc.execPopulate().then(resolve, reject);
  *
+ *   // you can also use doc.execPopulate(options) as a shorthand for
+ *   // doc.populate(options).execPopulate()
+ *
+ *
+ * ####Example:
+ *   const promise = doc.execPopulate({ path: 'company', select: 'employees' });
+ *
+ *   // summary
+ *   promise.then(resolve,reject);
  *
  * @see Document.populate #document_Document-populate
  * @api public
@@ -3622,6 +3631,11 @@ Document.prototype.populate = function populate() {
  */
 
 Document.prototype.execPopulate = function(callback) {
+  const isUsingShorthand = callback != null && typeof callback !== 'function';
+  if (isUsingShorthand) {
+    return this.populate(arguments).execPopulate();
+  }
+
   return promiseOrCallback(callback, cb => {
     this.populate(cb);
   }, this.constructor.events);

From ed81d05fe8fcc78394f93242e45594b556d4ffc3 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 23 Apr 2020 07:00:38 +0200
Subject: [PATCH 0744/2348] apply arguments instead of passing an array

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index fd2f21974cd..2fb343620b7 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3633,7 +3633,7 @@ Document.prototype.populate = function populate() {
 Document.prototype.execPopulate = function(callback) {
   const isUsingShorthand = callback != null && typeof callback !== 'function';
   if (isUsingShorthand) {
-    return this.populate(arguments).execPopulate();
+    return this.populate.apply(this, arguments).execPopulate();
   }
 
   return promiseOrCallback(callback, cb => {

From a359cc184688463178790cb370551dedd88d8e2b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 02:35:08 +0200
Subject: [PATCH 0745/2348] docs: fix race condition in creating connection for
 lambda

---
 docs/lambda.pug | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/docs/lambda.pug b/docs/lambda.pug
index 66f2cbce032..136e811c5ab 100644
--- a/docs/lambda.pug
+++ b/docs/lambda.pug
@@ -39,13 +39,17 @@ block content
       // This means your Lambda function doesn't have to go through the
       // potentially expensive process of connecting to MongoDB every time.
       if (conn == null) {
-        conn = await mongoose.createConnection(uri, {
+        conn = mongoose.createConnection(uri, {
           // Buffering means mongoose will queue up operations if it gets
           // disconnected from MongoDB and send them when it reconnects.
           // With serverless, better to fail fast if not connected.
           bufferCommands: false, // Disable mongoose buffering
           bufferMaxEntries: 0 // and MongoDB driver buffering
         });
+        
+        // `await`ing connection after assigning to the `conn` variable
+        // to avoid multiple function calls creating new connections
+        await conn;
         conn.model('Test', new mongoose.Schema({ name: String }));
       }
 

From 422ec472d3811b30c165fbf9115f738f304eee2b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 06:10:54 +0200
Subject: [PATCH 0746/2348] refactor: SchemaType#doValidate use early returns
 instead of nested conditions

---
 lib/document.js   |  14 +++---
 lib/schematype.js | 111 +++++++++++++++++++++++++---------------------
 2 files changed, 67 insertions(+), 58 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 650f1380495..8a1cbf942e8 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2136,10 +2136,10 @@ function _getPathsToValidate(doc) {
   }));
 
 
-  function addToPaths(p) { paths.add(p); }
   Object.keys(doc.$__.activePaths.states.init).forEach(addToPaths);
   Object.keys(doc.$__.activePaths.states.modify).forEach(addToPaths);
   Object.keys(doc.$__.activePaths.states.default).forEach(addToPaths);
+  function addToPaths(p) { paths.add(p); }
 
   const subdocs = doc.$__getAllSubdocs();
   const modifiedPaths = doc.modifiedPaths();
@@ -2340,9 +2340,9 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     total++;
 
     process.nextTick(function() {
-      const p = _this.schema.path(path);
+      const schemaType = _this.schema.path(path);
 
-      if (!p) {
+      if (!schemaType) {
         return --total || complete();
       }
 
@@ -2369,11 +2369,11 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
         skipSchemaValidators: skipSchemaValidators[path],
         path: path
       };
-      p.doValidate(val, function(err) {
-        if (err && (!p.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
-          if (p.$isSingleNested &&
+      schemaType.doValidate(val, function(err) {
+        if (err && (!schemaType.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
+          if (schemaType.$isSingleNested &&
               err instanceof ValidationError &&
-              p.schema.options.storeSubdocValidationError === false) {
+              schemaType.schema.options.storeSubdocValidationError === false) {
             return --total || complete();
           }
           _this.invalidate(path, err, undefined, true);
diff --git a/lib/schematype.js b/lib/schematype.js
index dba11cc145e..5fe73d6a012 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1089,26 +1089,6 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
     return fn(null);
   }
 
-  const validate = function(ok, validatorProperties) {
-    if (err) {
-      return;
-    }
-    if (ok === undefined || ok) {
-      if (--count <= 0) {
-        immediate(function() {
-          fn(null);
-        });
-      }
-    } else {
-      const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
-      err = new ErrorConstructor(validatorProperties);
-      err[validatorErrorSymbol] = true;
-      immediate(function() {
-        fn(err);
-      });
-    }
-  };
-
   const _this = this;
   validators.forEach(function(v) {
     if (err) {
@@ -1124,42 +1104,71 @@ SchemaType.prototype.doValidate = function(value, fn, scope, options) {
 
     if (validator instanceof RegExp) {
       validate(validator.test(value), validatorProperties);
-    } else if (typeof validator === 'function') {
-      if (value === undefined && validator !== _this.requiredValidator) {
-        validate(true, validatorProperties);
-        return;
-      }
-      if (validatorProperties.isAsync) {
-        asyncValidate(validator, scope, value, validatorProperties, validate);
+      return;
+    }
+
+    if (typeof validator !== 'function') {
+      return;
+    }
+
+    if (value === undefined && validator !== _this.requiredValidator) {
+      validate(true, validatorProperties);
+      return;
+    }
+
+    if (validatorProperties.isAsync) {
+      asyncValidate(validator, scope, value, validatorProperties, validate);
+      return;
+    }
+
+    try {
+      if (validatorProperties.propsParameter) {
+        ok = validator.call(scope, value, validatorProperties);
       } else {
-        try {
-          if (validatorProperties.propsParameter) {
-            ok = validator.call(scope, value, validatorProperties);
-          } else {
-            ok = validator.call(scope, value);
-          }
-        } catch (error) {
-          ok = false;
+        ok = validator.call(scope, value);
+      }
+    } catch (error) {
+      ok = false;
+      validatorProperties.reason = error;
+      if (error.message) {
+        validatorProperties.message = error.message;
+      }
+    }
+
+    if (ok != null && typeof ok.then === 'function') {
+      ok.then(
+        function(ok) { validate(ok, validatorProperties); },
+        function(error) {
           validatorProperties.reason = error;
-          if (error.message) {
-            validatorProperties.message = error.message;
-          }
-        }
-        if (ok != null && typeof ok.then === 'function') {
-          ok.then(
-            function(ok) { validate(ok, validatorProperties); },
-            function(error) {
-              validatorProperties.reason = error;
-              validatorProperties.message = error.message;
-              ok = false;
-              validate(ok, validatorProperties);
-            });
-        } else {
+          validatorProperties.message = error.message;
+          ok = false;
           validate(ok, validatorProperties);
-        }
-      }
+        });
+    } else {
+      validate(ok, validatorProperties);
     }
+
   });
+
+  function validate(ok, validatorProperties) {
+    if (err) {
+      return;
+    }
+    if (ok === undefined || ok) {
+      if (--count <= 0) {
+        immediate(function() {
+          fn(null);
+        });
+      }
+    } else {
+      const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
+      err = new ErrorConstructor(validatorProperties);
+      err[validatorErrorSymbol] = true;
+      immediate(function() {
+        fn(err);
+      });
+    }
+  }
 };
 
 /*!

From 572710fdba8331ad4ddd8b8de289ee20da4e0be6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 06:11:15 +0200
Subject: [PATCH 0747/2348] test: repro #8821

---
 test/model.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 4f31b4d2891..b37df5802e4 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6434,6 +6434,19 @@ describe('Model', function() {
     });
   });
 
+  it('Model.validate(...) validates paths in arrays (gh-8821)', function() {
+    const userSchema = new Schema({
+      friends: [{ type: String, required: true }]
+    });
+
+    const User = db.model('User', userSchema);
+    return co(function*() {
+      const err = yield new User({ friends: [null] }).validate().catch(err => err);
+
+      assert.ok(err.message.indexOf('`friends.0` is required') !== -1);
+    });
+  });
+
   it('sets correct `Document#op` with `save()` (gh-8439)', function() {
     const schema = Schema({ name: String });
     const ops = [];

From 97dbd6e47e318594c8e8bd4d284ed86ebc2769ec Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 06:12:26 +0200
Subject: [PATCH 0748/2348] test: use Model.validate(...) instead of
 Document#validate

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index b37df5802e4..4b7d5cabf4d 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6441,7 +6441,7 @@ describe('Model', function() {
 
     const User = db.model('User', userSchema);
     return co(function*() {
-      const err = yield new User({ friends: [null] }).validate().catch(err => err);
+      const err = yield User.validate({ friends: [null] }).catch(err => err);
 
       assert.ok(err.message.indexOf('`friends.0` is required') !== -1);
     });

From 57565502ea3eb019a2f07933d6502a22dbfc6ba8 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 06:22:30 +0200
Subject: [PATCH 0749/2348] fix: add nested array paths to Model.validate(...)
 paths

---
 lib/model.js | 33 +++++++++++++++++++++++++++++----
 1 file changed, 29 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index dcc172e4901..7365f59b077 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4029,11 +4029,22 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
       });
     }
 
+    for (const path of paths) {
+      const schemaType = schema.path(path);
+      if (!schemaType || !schemaType.$isMongooseArray) {
+        continue;
+      }
+
+      const val = get(obj, path);
+      pushNestedArrayPaths(val, path);
+    }
+
     let remaining = paths.length;
     let error = null;
+
     for (const path of paths) {
-      const schematype = schema.path(path);
-      if (schematype == null) {
+      const schemaType = schema.path(path);
+      if (schemaType == null) {
         _checkDone();
         continue;
       }
@@ -4048,7 +4059,7 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
 
       if (val != null) {
         try {
-          val = schematype.cast(val);
+          val = schemaType.cast(val);
           cur[pieces[pieces.length - 1]] = val;
         } catch (err) {
           error = error || new ValidationError();
@@ -4059,7 +4070,7 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
         }
       }
 
-      schematype.doValidate(val, err => {
+      schemaType.doValidate(val, err => {
         if (err) {
           error = error || new ValidationError();
           if (err instanceof ValidationError) {
@@ -4074,6 +4085,20 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
       }, context);
     }
 
+    function pushNestedArrayPaths(nestedArray, path) {
+      if (nestedArray == null) {
+        return;
+      }
+
+      for (let i = 0; i < nestedArray.length; ++i) {
+        if (Array.isArray(nestedArray[i])) {
+          pushNestedArrayPaths(nestedArray[i], path + '.' + i);
+        } else {
+          paths.push(path + '.' + i);
+        }
+      }
+    }
+
     function _checkDone() {
       if (--remaining <= 0) {
         return cb(error);

From afbde2b7720fe354129a4e89f3d34059dc4d7c71 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 07:08:50 +0200
Subject: [PATCH 0750/2348] test: verify Model.validate(...) returns errors for
 multiple elements in array

---
 test/model.test.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 4b7d5cabf4d..7259f164b40 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6441,9 +6441,10 @@ describe('Model', function() {
 
     const User = db.model('User', userSchema);
     return co(function*() {
-      const err = yield User.validate({ friends: [null] }).catch(err => err);
+      const err = yield User.validate({ friends: [null, ''] }).catch(err => err);
 
-      assert.ok(err.message.indexOf('`friends.0` is required') !== -1);
+      assert.ok(err.errors['friends.0']);
+      assert.ok(err.errors['friends.1']);
     });
   });
 

From f51f1975db3e5379692ad456475d28141ab56adc Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 07:11:42 +0200
Subject: [PATCH 0751/2348] fix(model): add `path` to schemaType.doValidate()
 in Model.validate()

---
 lib/model.js       | 2 +-
 test/model.test.js | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 7365f59b077..7fd6bbe2e31 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4082,7 +4082,7 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
           }
         }
         _checkDone();
-      }, context);
+      }, context, { path: path });
     }
 
     function pushNestedArrayPaths(nestedArray, path) {
diff --git a/test/model.test.js b/test/model.test.js
index 7259f164b40..2b28ac6c70d 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6436,12 +6436,12 @@ describe('Model', function() {
 
   it('Model.validate(...) validates paths in arrays (gh-8821)', function() {
     const userSchema = new Schema({
-      friends: [{ type: String, required: true }]
+      friends: [{ type: String, required: true, minlength: 3 }]
     });
 
     const User = db.model('User', userSchema);
     return co(function*() {
-      const err = yield User.validate({ friends: [null, ''] }).catch(err => err);
+      const err = yield User.validate({ friends: [null, 'A'] }).catch(err => err);
 
       assert.ok(err.errors['friends.0']);
       assert.ok(err.errors['friends.1']);

From 74638cc29f29b82d92dbb1747b41b73b2fb875b1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 07:55:03 +0200
Subject: [PATCH 0752/2348] refactor: use early returns on
 SchemaType#doValidate(...)

---
 lib/schematype.js | 61 +++++++++++++++++++++++++----------------------
 1 file changed, 33 insertions(+), 28 deletions(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index 5fe73d6a012..55961125df0 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1227,7 +1227,6 @@ function asyncValidate(validator, scope, value, props, cb) {
  */
 
 SchemaType.prototype.doValidateSync = function(value, scope, options) {
-  let err = null;
   const path = this.path;
   const count = this.validators.length;
 
@@ -1235,17 +1234,6 @@ SchemaType.prototype.doValidateSync = function(value, scope, options) {
     return null;
   }
 
-  const validate = function(ok, validatorProperties) {
-    if (err) {
-      return;
-    }
-    if (ok !== undefined && !ok) {
-      const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
-      err = new ErrorConstructor(validatorProperties);
-      err[validatorErrorSymbol] = true;
-    }
-  };
-
   let validators = this.validators;
   if (value === void 0) {
     if (this.validators.length > 0 && this.validators[0].type === 'required') {
@@ -1255,6 +1243,7 @@ SchemaType.prototype.doValidateSync = function(value, scope, options) {
     }
   }
 
+  let err = null;
   validators.forEach(function(v) {
     if (err) {
       return;
@@ -1278,28 +1267,44 @@ SchemaType.prototype.doValidateSync = function(value, scope, options) {
 
     if (validator instanceof RegExp) {
       validate(validator.test(value), validatorProperties);
-    } else if (typeof validator === 'function') {
-      try {
-        if (validatorProperties.propsParameter) {
-          ok = validator.call(scope, value, validatorProperties);
-        } else {
-          ok = validator.call(scope, value);
-        }
-      } catch (error) {
-        ok = false;
-        validatorProperties.reason = error;
-      }
+      return;
+    }
 
-      // Skip any validators that return a promise, we can't handle those
-      // synchronously
-      if (ok != null && typeof ok.then === 'function') {
-        return;
+    if (typeof validator !== 'function') {
+      return;
+    }
+
+    try {
+      if (validatorProperties.propsParameter) {
+        ok = validator.call(scope, value, validatorProperties);
+      } else {
+        ok = validator.call(scope, value);
       }
-      validate(ok, validatorProperties);
+    } catch (error) {
+      ok = false;
+      validatorProperties.reason = error;
+    }
+
+    // Skip any validators that return a promise, we can't handle those
+    // synchronously
+    if (ok != null && typeof ok.then === 'function') {
+      return;
     }
+    validate(ok, validatorProperties);
   });
 
   return err;
+
+  function validate(ok, validatorProperties) {
+    if (err) {
+      return;
+    }
+    if (ok !== undefined && !ok) {
+      const ErrorConstructor = validatorProperties.ErrorConstructor || ValidatorError;
+      err = new ErrorConstructor(validatorProperties);
+      err[validatorErrorSymbol] = true;
+    }
+  }
 };
 
 /**

From 7a249ba67deb6d590bb30b7fe4b1ff48bdea22b6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 11:47:05 +0200
Subject: [PATCH 0753/2348] refactor: remove unnecessary done on synchronous
 test

---
 test/schematype.test.js | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/test/schematype.test.js b/test/schematype.test.js
index ddfcbadf552..329e7eb8f2a 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -11,16 +11,15 @@ const assert = require('assert');
 const Schema = mongoose.Schema;
 
 describe('schematype', function() {
-  it('honors the selected option', function(done) {
+  it('honors the selected option', function() {
     const s = new Schema({ thought: { type: String, select: false } });
     assert.ok(!s.path('thought').selected);
 
     const a = new Schema({ thought: { type: String, select: true } });
     assert.ok(a.path('thought').selected);
-    done();
   });
 
-  it('properly handles specifying index in combination with unique or sparse', function(done) {
+  it('properly handles specifying index in combination with unique or sparse', function() {
     let s = new Schema({ name: { type: String, index: true, unique: true } });
     assert.deepEqual(s.path('name')._index, { unique: true });
     s = new Schema({ name: { type: String, unique: true, index: true } });
@@ -29,10 +28,9 @@ describe('schematype', function() {
     assert.deepEqual(s.path('name')._index, { sparse: true });
     s = new Schema({ name: { type: String, sparse: true, index: true } });
     assert.deepEqual(s.path('name')._index, { sparse: true });
-    done();
   });
 
-  it('handles index: false with unique, sparse, text set to false (gh-7620)', function(done) {
+  it('handles index: false with unique, sparse, text set to false (gh-7620)', function() {
     let s = new Schema({ name: { type: String, index: false, unique: false } });
     assert.equal(s.path('name')._index, false);
     s = new Schema({ name: { type: String, unique: false, index: false } });
@@ -47,8 +45,6 @@ describe('schematype', function() {
     assert.equal(s.path('name')._index, false);
     s = new Schema({ name: { type: String, text: false, index: false } });
     assert.equal(s.path('name')._index, false);
-
-    done();
   });
 
   describe('checkRequired()', function() {

From d7ccda4a459ff6e3347537afb38c8638ba005b32 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 12:03:04 +0200
Subject: [PATCH 0754/2348] test: repro #8849

---
 test/schema.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 3b8575bc76f..25a2a1b1a31 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -17,6 +17,7 @@ const Mixed = SchemaTypes.Mixed;
 const DocumentObjectId = mongoose.Types.ObjectId;
 const ReadPref = mongoose.mongo.ReadPreference;
 const vm = require('vm');
+const co = require('co');
 const Buffer = require('safe-buffer').Buffer;
 
 /**
@@ -2383,4 +2384,31 @@ describe('schema', function() {
     assert.equal(TurboManSchema.path('price').instance, 'Number');
     assert.equal(TurboManSchema.path('year').instance, 'Number');
   });
+
+  describe('gh-8849', function() {
+    it('treats `select: undefined` as not specifying `select` option', function() {
+      const userSchema = new Schema({ name: { type: String, select: undefined } });
+      const User = db.model('User', userSchema);
+
+      return co(function*() {
+        yield User.create({ name: 'Hafez' });
+        const user = yield User.findOne();
+
+        assert.equal(user.name, 'Hafez');
+      });
+    });
+
+    it('treats `select: null` as not specifying `select` option', function() {
+      const userSchema = new Schema({ name: { type: String, select: null } });
+      const User = db.model('User', userSchema);
+
+      return co(function*() {
+        yield User.create({ name: 'Hafez' });
+        const user = yield User.findOne();
+
+        assert.equal(user.name, 'Hafez');
+      });
+    });
+  });
+
 });

From e2d4a3d8c5b768a4c39d45ef8527636d4505ede9 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 12:03:40 +0200
Subject: [PATCH 0755/2348] fix(schemaType): treat select: null or select:
 undefined as not specified

---
 lib/schematype.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index dba11cc145e..b1de2cdce1f 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -55,10 +55,15 @@ function SchemaType(path, options, instance) {
   }
 
 
+  if (options.select == null) {
+    delete options.select;
+  }
+
   const Options = this.OptionsConstructor || SchemaTypeOptions;
   this.options = new Options(options);
   this._index = null;
-  this.selected;
+
+
   if (utils.hasUserDefinedProperty(this.options, 'immutable')) {
     this.$immutable = this.options.immutable;
 

From 85cd79f69c5b9de0f9e2d44d7ba0aa04fe8224b7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 24 Apr 2020 12:17:12 +0200
Subject: [PATCH 0756/2348] refactor: remove unnecessary `done` from
 synchronous tests

---
 test/aggregate.test.js | 125 +++++++++++------------------------------
 1 file changed, 34 insertions(+), 91 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 9dcfdc278c2..8fc56d44b97 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -97,7 +97,7 @@ describe('aggregate: ', function() {
   afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('append', function() {
-    it('(pipeline)', function(done) {
+    it('(pipeline)', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.append({ $a: 1 }, { $b: 2 }, { $c: 3 }), aggregate);
@@ -105,11 +105,9 @@ describe('aggregate: ', function() {
 
       aggregate.append({ $d: 4 }, { $c: 5 });
       assert.deepEqual(aggregate._pipeline, [{ $a: 1 }, { $b: 2 }, { $c: 3 }, { $d: 4 }, { $c: 5 }]);
-
-      done();
     });
 
-    it('supports array as single argument', function(done) {
+    it('supports array as single argument', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.append([{ $a: 1 }, { $b: 2 }, { $c: 3 }]), aggregate);
@@ -117,11 +115,9 @@ describe('aggregate: ', function() {
 
       aggregate.append([{ $d: 4 }, { $c: 5 }]);
       assert.deepEqual(aggregate._pipeline, [{ $a: 1 }, { $b: 2 }, { $c: 3 }, { $d: 4 }, { $c: 5 }]);
-
-      done();
     });
 
-    it('throws if non-operator parameter is passed', function(done) {
+    it('throws if non-operator parameter is passed', function() {
       const aggregate = new Aggregate();
       const regexp = /Arguments must be aggregate pipeline operators/;
 
@@ -140,33 +136,27 @@ describe('aggregate: ', function() {
       assert.throws(function() {
         aggregate.append([{ $a: 1 }, { a: 1 }]);
       }, regexp);
-
-      done();
     });
 
-    it('does not throw when 0 args passed', function(done) {
+    it('does not throw when 0 args passed', function() {
       const aggregate = new Aggregate();
 
       assert.doesNotThrow(function() {
         aggregate.append();
       });
-
-      done();
     });
 
-    it('does not throw when empty array is passed as single argument', function(done) {
+    it('does not throw when empty array is passed as single argument', function() {
       const aggregate = new Aggregate();
 
       assert.doesNotThrow(function() {
         aggregate.append([]);
       });
-
-      done();
     });
   });
 
   describe('project', function() {
-    it('(object)', function(done) {
+    it('(object)', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.project({ a: 1, b: 1, c: 0 }), aggregate);
@@ -174,11 +164,9 @@ describe('aggregate: ', function() {
 
       aggregate.project({ b: 1 });
       assert.deepEqual(aggregate._pipeline, [{ $project: { a: 1, b: 1, c: 0 } }, { $project: { b: 1 } }]);
-
-      done();
     });
 
-    it('(string)', function(done) {
+    it('(string)', function() {
       const aggregate = new Aggregate();
 
       aggregate.project(' a b   -c  ');
@@ -186,31 +174,25 @@ describe('aggregate: ', function() {
 
       aggregate.project('b');
       assert.deepEqual(aggregate._pipeline, [{ $project: { a: 1, b: 1, c: 0 } }, { $project: { b: 1 } }]);
-
-      done();
     });
 
-    it('("a","b","c")', function(done) {
+    it('("a","b","c")', function() {
       assert.throws(function() {
         const aggregate = new Aggregate();
         aggregate.project('a', 'b', 'c');
       }, /Invalid project/);
-
-      done();
     });
 
-    it('["a","b","c"]', function(done) {
+    it('["a","b","c"]', function() {
       assert.throws(function() {
         const aggregate = new Aggregate();
         aggregate.project(['a', 'b', 'c']);
       }, /Invalid project/);
-
-      done();
     });
   });
 
   describe('group', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.group({ a: 1, b: 2 }), aggregate);
@@ -218,13 +200,11 @@ describe('aggregate: ', function() {
 
       aggregate.group({ c: 3 });
       assert.deepEqual(aggregate._pipeline, [{ $group: { a: 1, b: 2 } }, { $group: { c: 3 } }]);
-
-      done();
     });
   });
 
   describe('skip', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.skip(42), aggregate);
@@ -232,13 +212,11 @@ describe('aggregate: ', function() {
 
       aggregate.skip(42);
       assert.deepEqual(aggregate._pipeline, [{ $skip: 42 }, { $skip: 42 }]);
-
-      done();
     });
   });
 
   describe('limit', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.limit(42), aggregate);
@@ -246,13 +224,11 @@ describe('aggregate: ', function() {
 
       aggregate.limit(42);
       assert.deepEqual(aggregate._pipeline, [{ $limit: 42 }, { $limit: 42 }]);
-
-      done();
     });
   });
 
   describe('unwind', function() {
-    it('("field")', function(done) {
+    it('("field")', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.unwind('field'), aggregate);
@@ -265,13 +241,11 @@ describe('aggregate: ', function() {
         { $unwind: '$b' },
         { $unwind: '$c' }
       ]);
-
-      done();
     });
   });
 
   describe('match', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.match({ a: 1 }), aggregate);
@@ -279,13 +253,11 @@ describe('aggregate: ', function() {
 
       aggregate.match({ b: 2 });
       assert.deepEqual(aggregate._pipeline, [{ $match: { a: 1 } }, { $match: { b: 2 } }]);
-
-      done();
     });
   });
 
   describe('sort', function() {
-    it('(object)', function(done) {
+    it('(object)', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.sort({ a: 1, b: 'asc', c: 'descending' }), aggregate);
@@ -293,11 +265,9 @@ describe('aggregate: ', function() {
 
       aggregate.sort({ b: 'desc' });
       assert.deepEqual(aggregate._pipeline, [{ $sort: { a: 1, b: 1, c: -1 } }, { $sort: { b: -1 } }]);
-
-      done();
     });
 
-    it('(string)', function(done) {
+    it('(string)', function() {
       const aggregate = new Aggregate();
 
       aggregate.sort(' a b   -c  ');
@@ -305,31 +275,25 @@ describe('aggregate: ', function() {
 
       aggregate.sort('b');
       assert.deepEqual(aggregate._pipeline, [{ $sort: { a: 1, b: 1, c: -1 } }, { $sort: { b: 1 } }]);
-
-      done();
     });
 
-    it('("a","b","c")', function(done) {
+    it('("a","b","c")', function() {
       assert.throws(function() {
         const aggregate = new Aggregate();
         aggregate.sort('a', 'b', 'c');
       }, /Invalid sort/);
-
-      done();
     });
 
-    it('["a","b","c"]', function(done) {
+    it('["a","b","c"]', function() {
       assert.throws(function() {
         const aggregate = new Aggregate();
         aggregate.sort(['a', 'b', 'c']);
       }, /Invalid sort/);
-
-      done();
     });
   });
 
   describe('near', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
 
       assert.equal(aggregate.near({ a: 1 }), aggregate);
@@ -337,11 +301,9 @@ describe('aggregate: ', function() {
 
       aggregate.near({ b: 2 });
       assert.deepEqual(aggregate._pipeline, [{ $geoNear: { a: 1 } }, { $geoNear: { b: 2 } }]);
-
-      done();
     });
 
-    it('works with discriminators (gh-3304)', function(done) {
+    it('works with discriminators (gh-3304)', function() {
       let aggregate = new Aggregate();
       const stub = {
         schema: {
@@ -368,13 +330,11 @@ describe('aggregate: ', function() {
       Aggregate._prepareDiscriminatorPipeline(aggregate);
       assert.deepEqual(aggregate._pipeline,
         [{ $geoNear: { b: 2, query: { x: 1, __t: 'subschema' } } }]);
-
-      done();
     });
   });
 
   describe('lookup', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
       const obj = {
         from: 'users',
@@ -387,24 +347,22 @@ describe('aggregate: ', function() {
 
       assert.equal(aggregate._pipeline.length, 1);
       assert.deepEqual(aggregate._pipeline[0].$lookup, obj);
-      done();
     });
   });
 
   describe('sample', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
 
       aggregate.sample(3);
 
       assert.equal(aggregate._pipeline.length, 1);
       assert.deepEqual(aggregate._pipeline[0].$sample, { size: 3 });
-      done();
     });
   });
 
   describe('model()', function() {
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
       const model = { foo: 42 };
 
@@ -414,14 +372,12 @@ describe('aggregate: ', function() {
       assert.equal(aggregate.model(model), aggregate);
       assert.equal(aggregate._model, model);
       assert.equal(aggregate.model(), model);
-
-      done();
     });
   });
 
   describe('redact', function() {
     const pipelineResult = [{ $redact: { $cond: { if: { $eq: ['$level', 5] }, then: '$$PRUNE', else: '$$DESCEND' } } }];
-    it('works', function(done) {
+    it('works', function() {
       const aggregate = new Aggregate();
       aggregate.redact({
         $cond: {
@@ -431,15 +387,11 @@ describe('aggregate: ', function() {
         }
       });
       assert.deepEqual(aggregate._pipeline, pipelineResult);
-
-      done();
     });
-    it('works with (condition, string, string)', function(done) {
+    it('works with (condition, string, string)', function() {
       const aggregate = new Aggregate();
       aggregate.redact({ $eq: ['$level', 5] }, '$$PRUNE', '$$DESCEND');
       assert.deepEqual(aggregate._pipeline, pipelineResult);
-
-      done();
     });
   });
 
@@ -449,7 +401,7 @@ describe('aggregate: ', function() {
     });
 
     describe('graphLookup', function() {
-      it('works', function(done) {
+      it('works', function() {
         const aggregate = new Aggregate();
         aggregate.graphLookup({
           startWith: '$test',
@@ -465,10 +417,9 @@ describe('aggregate: ', function() {
           connectFromField: 'testFromField',
           connectToField: '_id'
         });
-        done();
       });
 
-      it('automatically prepends $ to the startWith field', function(done) {
+      it('automatically prepends $ to the startWith field', function() {
         const aggregate = new Aggregate();
         aggregate.graphLookup({
           startWith: 'test'
@@ -477,7 +428,6 @@ describe('aggregate: ', function() {
         assert.deepEqual(aggregate._pipeline[0].$graphLookup, {
           startWith: '$test'
         });
-        done();
       });
 
       it('Throws if no options are passed to graphLookup', function(done) {
@@ -493,7 +443,7 @@ describe('aggregate: ', function() {
     });
 
     describe('addFields', function() {
-      it('(object)', function(done) {
+      it('(object)', function() {
         const aggregate = new Aggregate();
 
         assert.equal(aggregate.addFields({ a: 1, b: 1, c: 0 }), aggregate);
@@ -501,12 +451,11 @@ describe('aggregate: ', function() {
 
         aggregate.addFields({ d: { $add: ['$a', '$b'] } });
         assert.deepEqual(aggregate._pipeline, [{ $addFields: { a: 1, b: 1, c: 0 } }, { $addFields: { d: { $add: ['$a', '$b'] } } }]);
-        done();
       });
     });
 
     describe('facet', function() {
-      it('works', function(done) {
+      it('works', function() {
         const aggregate = new Aggregate();
 
         aggregate.facet({
@@ -548,60 +497,54 @@ describe('aggregate: ', function() {
             }
           ]
         });
-        done();
       });
     });
 
     describe('replaceRoot', function() {
-      it('works with a string', function(done) {
+      it('works with a string', function() {
         const aggregate = new Aggregate();
 
         aggregate.replaceRoot('myNewRoot');
 
         assert.deepEqual(aggregate._pipeline,
           [{ $replaceRoot: { newRoot: '$myNewRoot' } }]);
-        done();
       });
-      it('works with an object (gh-6474)', function(done) {
+      it('works with an object (gh-6474)', function() {
         const aggregate = new Aggregate();
 
         aggregate.replaceRoot({ x: { $concat: ['$this', '$that'] } });
 
         assert.deepEqual(aggregate._pipeline,
           [{ $replaceRoot: { newRoot: { x: { $concat: ['$this', '$that'] } } } }]);
-        done();
       });
     });
 
     describe('count', function() {
-      it('works', function(done) {
+      it('works', function() {
         const aggregate = new Aggregate();
 
         aggregate.count('countResult');
 
         assert.deepEqual(aggregate._pipeline, [{ $count: 'countResult' }]);
-        done();
       });
     });
 
     describe('sortByCount', function() {
-      it('works with a string argument', function(done) {
+      it('works with a string argument', function() {
         const aggregate = new Aggregate();
 
         aggregate.sortByCount('countedField');
 
         assert.deepEqual(aggregate._pipeline, [{ $sortByCount: '$countedField' }]);
-        done();
       });
 
-      it('works with an object argument', function(done) {
+      it('works with an object argument', function() {
         const aggregate = new Aggregate();
 
         aggregate.sortByCount({ lname: '$employee.last' });
 
         assert.deepEqual(aggregate._pipeline,
           [{ $sortByCount: { lname: '$employee.last' } }]);
-        done();
       });
 
       it('throws if the argument is neither a string or object', function(done) {

From 13a6d2b2f9355a5ec4be57390a2d8e87054c1913 Mon Sep 17 00:00:00 2001
From: Tushar Sharma <ts17995@gmail.com>
Date: Sat, 25 Apr 2020 01:33:23 +0530
Subject: [PATCH 0757/2348] fix(model): return validation errors when all docs
 are invalid & rawResult is true

---
 lib/model.js       |  8 +++++
 test/model.test.js | 77 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index dcc172e4901..b37072767ce 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3350,6 +3350,14 @@ Model.$__insertMany = function(arr, options, callback) {
     });
     // Quickly escape while there aren't any valid docAttributes
     if (docAttributes.length < 1) {
+      if (rawResult) {
+        const res = {
+          mongoose: {
+            validationErrors: validationErrors
+          }
+        };
+        return callback(null, res);
+      }
       callback(null, []);
       return;
     }
diff --git a/test/model.test.js b/test/model.test.js
index 4f31b4d2891..04aacf7bc5a 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4651,6 +4651,83 @@ describe('Model', function() {
       });
     });
 
+    it('insertMany() validation error with ordered true when all documents are invalid', function(done) {
+      const schema = new Schema({
+        name: { type: String, required: true }
+      });
+      const Movie = db.model('Movie', schema);
+
+      const arr = [
+        { foo: 'The Phantom Menace' },
+        { foobar: 'The Force Awakens' }
+      ];
+      const opts = { ordered: true };
+      Movie.insertMany(arr, opts, function(error, res) {
+        assert.ok(error);
+        assert.equal(res, undefined);
+        assert.equal(error.name, 'ValidationError');
+        done();
+      });
+    });
+
+    it('insertMany() validation error with ordered false when all documents are invalid', function(done) {
+      const schema = new Schema({
+        name: { type: String, required: true }
+      });
+      const Movie = db.model('Movie', schema);
+
+      const arr = [
+        { foo: 'The Phantom Menace' },
+        { foobar: 'The Force Awakens' }
+      ];
+      const opts = { ordered: false };
+      Movie.insertMany(arr, opts, function(error, res) {
+        assert.ifError(error);
+        assert.equal(res.length, 0);
+        assert.equal(error, null);
+        done();
+      });
+    });
+
+    it('insertMany() validation error with ordered true and rawResult true when all documents are invalid', function(done) {
+      const schema = new Schema({
+        name: { type: String, required: true }
+      });
+      const Movie = db.model('Movie', schema);
+
+      const arr = [
+        { foo: 'The Phantom Menace' },
+        { foobar: 'The Force Awakens' }
+      ];
+      const opts = { ordered: true, rawResult: true };
+      Movie.insertMany(arr, opts, function(error, res) {
+        assert.ok(error);
+        assert.equal(res, undefined);
+        assert.equal(error.name, 'ValidationError');
+        done();
+      });
+    });
+
+    it('insertMany() validation error with ordered false and rawResult true when all documents are invalid', function(done) {
+      const schema = new Schema({
+        name: { type: String, required: true }
+      });
+      const Movie = db.model('Movie', schema);
+
+      const arr = [
+        { foo: 'The Phantom Menace' },
+        { foobar: 'The Force Awakens' }
+      ];
+      const opts = { ordered: false, rawResult: true };
+      Movie.insertMany(arr, opts, function(error, res) {
+        assert.ifError(error);
+        assert.equal(res.mongoose.validationErrors.length, 2);
+        assert.equal(res.mongoose.validationErrors[0].name, 'ValidationError');
+        assert.equal(res.mongoose.validationErrors[1].name, 'ValidationError');
+        done();
+      });
+    });
+
     it('insertMany() depopulate (gh-4590)', function(done) {
       const personSchema = new Schema({
         name: String

From 49e78aced9812c75375a3151e9dfb691b18dbbe4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 24 Apr 2020 19:28:23 -0400
Subject: [PATCH 0758/2348] docs: use ES6 classes for custom schema type
 example

Fix #8802
---
 test/docs/schematypes.test.js | 37 ++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/test/docs/schematypes.test.js b/test/docs/schematypes.test.js
index 92a4fe0a9c6..5f994709834 100644
--- a/test/docs/schematypes.test.js
+++ b/test/docs/schematypes.test.js
@@ -28,26 +28,27 @@ describe('schemaTypes', function () {
    * method you need to implement is the `cast()` method.
    */
   it('Creating a Basic Custom Schema Type', function() {
-    function Int8(key, options) {
-      mongoose.SchemaType.call(this, key, options, 'Int8');
-    }
-    Int8.prototype = Object.create(mongoose.SchemaType.prototype);
-
-    // `cast()` takes a parameter that can be anything. You need to
-    // validate the provided `val` and throw a `CastError` if you
-    // can't convert it.
-    Int8.prototype.cast = function(val) {
-      var _val = Number(val);
-      if (isNaN(_val)) {
-        throw new Error('Int8: ' + val + ' is not a number');
+    class Int8 extends mongoose.SchemaType {
+      constructor(key, options) {
+        super(key, options, 'Int8');
       }
-      _val = Math.round(_val);
-      if (_val < -0x80 || _val > 0x7F) {
-        throw new Error('Int8: ' + val +
-          ' is outside of the range of valid 8-bit ints');
+
+      // `cast()` takes a parameter that can be anything. You need to
+      // validate the provided `val` and throw a `CastError` if you
+      // can't convert it.
+      cast(val) {
+        var _val = Number(val);
+        if (isNaN(_val)) {
+          throw new Error('Int8: ' + val + ' is not a number');
+        }
+        _val = Math.round(_val);
+        if (_val < -0x80 || _val > 0x7F) {
+          throw new Error('Int8: ' + val +
+            ' is outside of the range of valid 8-bit ints');
+        }
+        return _val;
       }
-      return _val;
-    };
+    }
 
     // Don't forget to add `Int8` to the type registry
     mongoose.Schema.Types.Int8 = Int8;

From f5b9b262bd54d025be1278630079e13af16fc508 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Apr 2020 16:21:33 -0400
Subject: [PATCH 0759/2348] docs(faq): clarify setting paths under document
 arrays with `markModified()`

Fix #8854
---
 docs/faq.pug | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index c3de778b364..3dfaaaa3218 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -42,21 +42,36 @@ block content
 
     **A**. Mongoose doesn't create getters/setters for array indexes; without
     them mongoose never gets notified of the change and so doesn't know to
-    persist the new value. The work-around is to use
-    [MongooseArray#set](./api.html#types_array_MongooseArray.set) available
-    in **Mongoose >= 3.2.0**.
+    persist the new value. There are two workarounds:
+    [`MongooseArray#set`](./api.html#types_array_MongooseArray.set) or
+    [`Document#markModified()`](/docs/api/document.html#document_Document-markModified).
 
     ```javascript
-    // 3.2.0
+    // Saves changes successfully
     doc.array.set(3, 'changed');
     doc.save();
 
-    // if running a version less than 3.2.0, you must mark the array modified before saving.
+    // Also saves changes successfully
     doc.array[3] = 'changed';
     doc.markModified('array');
     doc.save();
     ```
 
+    This **only** affects when you set an array index directly. If you set
+    a path on a document array element, you do not need to use `markModified()`.
+
+    ```javascript
+    // Saves changes successfully without `markModified()`, because this
+    // code doesn't set an array index, it sets a path underneath an array index.
+    doc.docArray[3].name = 'changed';
+    doc.save();
+
+    // Does **not** save changes successfully. You need to use `markModified()`
+    // or `set()` because this sets an array index.
+    doc.docArray[3] = { name: 'changed' };
+    doc.save();
+    ```
+
     <hr id="unique-doesnt-work" />
 
     <a href="#unique-doesnt-work">**Q**</a>. I declared a schema property as `unique` but I can still save

From 63678a88f43f95dcccd9d1b359b83a8ffe14324e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Apr 2020 20:58:24 -0400
Subject: [PATCH 0760/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 960b37a55d4..f2c6129228e 100644
--- a/index.pug
+++ b/index.pug
@@ -322,6 +322,9 @@ html(lang='en')
               <a href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
                 <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://alltimelist.com/">
+                <img class="sponsor" src="https://images.opencollective.com/all-time-list/b04f3ee/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 8b055cfa6a484608a584df500463d77a5bd002c0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Apr 2020 12:11:46 -0400
Subject: [PATCH 0761/2348] fix(populate): handle `clone` with `lean` when
 setting a path to `null`

Fix #8807
---
 lib/helpers/populate/assignRawDocsToIdStructure.js | 2 +-
 test/model.populate.test.js                        | 8 +++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/populate/assignRawDocsToIdStructure.js b/lib/helpers/populate/assignRawDocsToIdStructure.js
index d46f87df65d..843c148373e 100644
--- a/lib/helpers/populate/assignRawDocsToIdStructure.js
+++ b/lib/helpers/populate/assignRawDocsToIdStructure.js
@@ -56,7 +56,7 @@ function assignRawDocsToIdStructure(rawIds, resultDocs, resultOrder, options, re
 
     doc = resultDocs[sid];
     // If user wants separate copies of same doc, use this option
-    if (options.clone) {
+    if (options.clone && doc != null) {
       if (options.lean) {
         const _model = leanPopulateMap.get(doc);
         doc = utils.clone(doc);
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 973f71d3f8f..e5b08f4ee6d 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9290,17 +9290,19 @@ describe('model: populate:', function() {
         const user = yield User.create({ name: 'val' });
         yield Post.create([
           { title: 'test1', user: user },
-          { title: 'test2', user: user }
+          { title: 'test2', user: user },
+          { title: 'test3', user: new mongoose.Types.ObjectId() }
         ]);
 
         const posts = yield Post.find().populate({ path: 'user', options: { clone: true } }).lean();
 
         posts[0].user.name = 'val2';
         assert.equal(posts[1].user.name, 'val');
+        assert.equal(posts[2].user, null);
       });
     });
 
-    it('clone with populate and lean makes child lean', function() { {
+    it('clone with populate and lean makes child lean', function() {
       const isLean = v => v != null && !(v instanceof mongoose.Document);
 
       const userSchema = new Schema({ name: String });
@@ -9322,6 +9324,6 @@ describe('model: populate:', function() {
 
         assert.ok(isLean(post.user));
       });
-    }});
+    });
   });
 });
\ No newline at end of file

From fa0a67caca0f1b4459a0e68973bbf9293d6b5367 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 26 Apr 2020 19:02:25 +0200
Subject: [PATCH 0762/2348] Remove unnecessary { strict: false } from test

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 4f31b4d2891..2b636806925 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6577,7 +6577,7 @@ describe('Model', function() {
         { notInSchema: 1 },
         { notInSchema: 2 },
         { notInSchema: 3 }
-      ], { strict: false }).then(res=>res.ops);
+      ]).then(res=>res.ops);
 
       // Act
       yield User.bulkWrite([

From 46326894a9e2bfc132fe61da61db66f840d16998 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 26 Apr 2020 21:47:17 +0200
Subject: [PATCH 0763/2348] docs(model): add options.overwrite to
 findOneAndUpdate and findByIdAndUpdate

---
 lib/model.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index b6431c37fe0..6fc0d358e85 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2481,6 +2481,7 @@ Model.$where = function $where() {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
+ * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `doc`, Mongoose will wrap `doc` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`.
  * @param {Function} [callback]
  * @return {Query}
  * @see Tutorial /docs/tutorials/findoneandupdate.html
@@ -2623,6 +2624,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
+ * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `doc`, Mongoose will wrap `doc` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`.
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndUpdate #model_Model.findOneAndUpdate

From 8ac1529253900a321919e1cb6ab534cf3f6d96af Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 26 Apr 2020 21:53:09 +0200
Subject: [PATCH 0764/2348] Add note for replaceOne as an alternative

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 6fc0d358e85..bb5cf72e180 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2481,7 +2481,7 @@ Model.$where = function $where() {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
- * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `doc`, Mongoose will wrap `doc` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`.
+ * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. This is an equivalent to using [Model.findOne(...)](https://mongoosejs.com/docs/api/model.html#model_Model.findOne), and [Model.replaceOne(...)](https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne).
  * @param {Function} [callback]
  * @return {Query}
  * @see Tutorial /docs/tutorials/findoneandupdate.html
@@ -2624,7 +2624,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
- * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `doc`, Mongoose will wrap `doc` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`.
+ * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. This is an equivalent to using [Model.findById(...)](https://mongoosejs.com/docs/api/model.html#model_Model.findById), and [Model.replaceOne(...)](https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne).
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndUpdate #model_Model.findOneAndUpdate

From f70ad717c44b1c599d2bc19ec6ac1670ec7c5bd5 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 10:24:51 +0200
Subject: [PATCH 0765/2348] docs(model): add findOneAndReplace as a more
 relevant alternative to overwrite

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index bb5cf72e180..8c7c91739fc 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2481,7 +2481,7 @@ Model.$where = function $where() {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
- * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. This is an equivalent to using [Model.findOne(...)](https://mongoosejs.com/docs/api/model.html#model_Model.findOne), and [Model.replaceOne(...)](https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne).
+ * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. An alternative to this would be using [Model.findOneAndReplace(conditions, update, options, callback)](https://mongoosejs.com/docs/api/model.html#model_Model.findOneAndReplace).
  * @param {Function} [callback]
  * @return {Query}
  * @see Tutorial /docs/tutorials/findoneandupdate.html
@@ -2624,7 +2624,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
- * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. This is an equivalent to using [Model.findById(...)](https://mongoosejs.com/docs/api/model.html#model_Model.findById), and [Model.replaceOne(...)](https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne).
+ * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. An alternative to this would be using [Model.findOneAndReplace({ _id: id }, update, options, callback)](https://mongoosejs.com/docs/api/model.html#model_Model.findOneAndReplace).
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndUpdate #model_Model.findOneAndUpdate

From 65ca4431d6fa38ce5746e0e382514c2681b5af54 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 10:54:06 +0200
Subject: [PATCH 0766/2348] test: repro #8869

---
 test/schema.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 25a2a1b1a31..1c3a070a897 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2411,4 +2411,23 @@ describe('schema', function() {
     });
   });
 
+  describe('Schema.reserved (gh-8869)', function() {
+    it('throws errors on compiling schema with reserved key as a flat type', function() {
+      const buildInvalidSchema = () => new Schema({ db: String });
+
+      assert.throws(buildInvalidSchema, { message: /`db` may not be used as a schema pathname/ });
+    });
+
+    it('throws errors on compiling schema with reserved key as a nested object', function() {
+      const buildInvalidSchema = () => new Schema({ db: { nested: String } });
+
+      assert.throws(buildInvalidSchema, { message: /`db` may not be used as a schema pathname/ });
+    });
+
+    it('throws errors on compiling schema with reserved key as a nested array', function() {
+      const buildInvalidSchema = () => new Schema({ db: [{ nested: String }] });
+
+      assert.throws(buildInvalidSchema, { message: /`db` may not be used as a schema pathname/ });
+    });
+  });
 });

From c04a50d591c6b778295f7e7e8a578695a43c5504 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 10:59:16 +0200
Subject: [PATCH 0767/2348] fix(schema): split path name when validating if
 it's reserved

---
 lib/schema.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 1f1ce46fa56..dab66f61338 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -642,8 +642,9 @@ Schema.prototype.path = function(path, obj) {
   }
 
   // some path names conflict with document methods
-  if (reserved[path]) {
-    throw new Error('`' + path + '` may not be used as a schema pathname');
+  const firstPieceOfPath = path.split('.')[0];
+  if (reserved[firstPieceOfPath]) {
+    throw new Error('`' + firstPieceOfPath + '` may not be used as a schema pathname');
   }
 
   if (warnings[path]) {

From 44dd87659096f38cfc53f9d71e095d4eb418c499 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 11:06:57 +0200
Subject: [PATCH 0768/2348] automatically add arrow spaces by eslint

---
 lib/model.js              | 2 +-
 package.json              | 4 ++++
 test/model.test.js        | 6 +++---
 test/query.cursor.test.js | 4 ++--
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index b6431c37fe0..80bba74f123 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -317,7 +317,7 @@ Model.prototype.$__handleSave = function(options, callback) {
     } else {
       const optionsWithCustomValues = Object.assign({}, options, saveOptions);
       this.constructor.exists(this.$__where(), optionsWithCustomValues)
-        .then((documentExists)=>{
+        .then((documentExists) => {
           if (!documentExists) throw new DocumentNotFoundError(this.$__where(), this.constructor.modelName);
 
           this.$__reset();
diff --git a/package.json b/package.json
index fff8835e7e6..8b9051a2aac 100644
--- a/package.json
+++ b/package.json
@@ -156,6 +156,10 @@
         }
       ],
       "array-bracket-spacing": 1,
+      "arrow-spacing": ["error", {
+        "before": true,
+        "after": true
+      }],
       "object-curly-spacing": [
         "error",
         "always"
diff --git a/test/model.test.js b/test/model.test.js
index bfbab1f16ee..6bd5082acb9 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5624,8 +5624,8 @@ describe('Model', function() {
               filter: { _id: createdUser._id }
             }
           }])
-            .then(()=>null)
-            .catch(err=>err);
+            .then(() => null)
+            .catch(err => err);
 
 
           assert.ok(err);
@@ -6668,7 +6668,7 @@ describe('Model', function() {
         { notInSchema: 1 },
         { notInSchema: 2 },
         { notInSchema: 3 }
-      ]).then(res=>res.ops);
+      ]).then(res => res.ops);
 
       // Act
       yield User.bulkWrite([
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index b122cff5e14..dcd322679cc 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -536,7 +536,7 @@ describe('QueryCursor', function() {
     const User = db.model('User', new Schema({ name: String }));
 
     const cursor = User.find().cursor();
-    cursor.on('data', ()=>{});
+    cursor.on('data', () => {});
 
     let closeEventTriggeredCount = 0;
     cursor.on('close', () => closeEventTriggeredCount++);
@@ -551,7 +551,7 @@ describe('QueryCursor', function() {
     const User = db.model('User', new Schema({ name: String }));
 
     const cursor = User.aggregate([{ $match: {} }]).cursor().exec();
-    cursor.on('data', ()=>{});
+    cursor.on('data', () => {});
 
     let closeEventTriggeredCount = 0;
     cursor.on('close', () => closeEventTriggeredCount++);

From 616b86377a0e115aff8c1f2743f2320326dfe07d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 11:35:12 +0200
Subject: [PATCH 0769/2348] docs(model): adds options.limit to
 Model.insertMany(...)

---
 lib/model.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/model.js b/lib/model.js
index b6431c37fe0..1fe219568e2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3262,6 +3262,7 @@ Model.startSession = function() {
  * @param {Boolean} [options.ordered = true] if true, will fail fast on the first error encountered. If false, will insert all the documents it can and report errors later. An `insertMany()` with `ordered = false` is called an "unordered" `insertMany()`.
  * @param {Boolean} [options.rawResult = false] if false, the returned promise resolves to the documents that passed mongoose document validation. If `true`, will return the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~insertWriteOpCallback) with a `mongoose` property that contains `validationErrors` if this is an unordered `insertMany`.
  * @param {Boolean} [options.lean = false] if `true`, skips hydrating and validating the documents. This option is useful if you need the extra performance, but Mongoose won't validate the documents before inserting.
+ * @param {Number} [options.limit = null] this limits the number of documents being processed (validation/casting) by mongoose in parallel, this does **NOT** send the documents in batches to MongoDB. Use this option if you're processing a large number of documents and your app is running out of memory.
  * @param {Function} [callback] callback
  * @return {Promise} resolving to the raw result from the MongoDB driver if `options.rawResult` was `true`, or the documents that passed validation, otherwise
  * @api public

From e6c04a53c126611d0ae5361030fd8c5b11c0a06e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 13:21:51 +0200
Subject: [PATCH 0770/2348] test: repro #8837

---
 test/model.populate.test.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index e5b08f4ee6d..b2afcb57b06 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9325,5 +9325,35 @@ describe('model: populate:', function() {
         assert.ok(isLean(post.user));
       });
     });
+
+    it('can populate subdocs where one is discriminator and the other is not (gh-8837)', function() {
+      return co(function*() {
+        const eventSchema = new Schema({ }, { discriminatorKey: 'type' });
+        const eventsListSchema = new Schema({ events: [eventSchema] });
+
+        const clickEventSchema = new Schema({
+          modelName: { type: String, required: true },
+          productId: { type: Schema.ObjectId, refPath: 'events.modelName' }
+        });
+
+        const eventsSchemaType = eventsListSchema.path('events');
+        eventsSchemaType.discriminator('ClickEvent', clickEventSchema);
+
+        const EventsList = db.model('EventsList', eventsListSchema);
+        const Product = db.model('Product', new Schema({ name: String }));
+
+        const product = yield Product.create({ name: 'GTX 1050 Ti' });
+
+        yield EventsList.create({
+          events: [
+            { },
+            { type: 'ClickEvent', modelName: 'Product', productId: product._id }
+          ]
+        });
+
+        const result = yield EventsList.findOne().populate('events.productId');
+        assert.equal(result.events[1].productId.name, 'GTX 1050 Ti');
+      });
+    });
   });
 });
\ No newline at end of file

From 760b1e5448d16bca06edc3c74c2a22522e55f0f0 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 13:25:22 +0200
Subject: [PATCH 0771/2348] fix(model): verify discriminator existence before
 trying to access it

---
 lib/helpers/populate/getModelsMapForPopulate.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index c375baca0d9..0411f145322 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -229,8 +229,9 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           const discriminatorKey = schematype.caster.schema.options.discriminatorKey;
           modelNames = [];
           for (const subdoc of subdocs) {
-            const discriminatorValue = utils.getValue(discriminatorKey, subdoc);
-            const discriminatorSchema = schematype.caster.discriminators[discriminatorValue].schema;
+            const discriminatorName = utils.getValue(discriminatorKey, subdoc);
+            const discriminator = schematype.caster.discriminators[discriminatorName];
+            const discriminatorSchema = discriminator && discriminator.schema;
             if (discriminatorSchema == null) {
               continue;
             }

From f967f5715bef9b8bb4a47a817608a464a0c6d189 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 27 Apr 2020 17:55:32 +0200
Subject: [PATCH 0772/2348] Upgrade eslint to v6.8.0

---
 package.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index fff8835e7e6..0b7a170f4de 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "cheerio": "1.0.0-rc.2",
     "co": "4.6.0",
     "dox": "0.3.1",
-    "eslint": "5.16.0",
+    "eslint": "6.8.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.1.0",
     "lodash.isequal": "4.5.0",
@@ -207,4 +207,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
\ No newline at end of file
+}

From 04d32f3905d706130e272fbeed0c4452be6e7ae2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 28 Apr 2020 13:57:20 +0200
Subject: [PATCH 0773/2348] test: repro #8267

---
 test/connection.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index b034f9a865d..152e3142781 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1198,4 +1198,13 @@ describe('connections:', function() {
       assert.equal(changes[0].operationType, 'insert');
     });
   });
+
+  it('useDB inherits config from default conneciton (gh-8267)', function() {
+    return co(function*() {
+      yield mongoose.connect('mongodb://localhost:27017/gh8267-0', { useCreateIndex: true });
+
+      const db2 = mongoose.connection.useDb('gh8267-1');
+      assert.equal(db2.config.useCreateIndex, true);
+    });
+  });
 });

From 883c30b2b044457c63dbafa4012c1da969ea5915 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 28 Apr 2020 14:05:10 +0200
Subject: [PATCH 0774/2348] fix(connection): make connection returned from
 useDb inherit config from default connection

---
 lib/drivers/node-mongodb-native/connection.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index 5fb8c8dd055..f7a59442310 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -58,6 +58,7 @@ NativeConnection.prototype.useDb = function(name, options) {
   newConn.collections = {};
   newConn.models = {};
   newConn.replica = this.replica;
+  newConn.config = Object.assign(newConn.config, this.base.connection.config);
   newConn.name = this.name;
   newConn.options = this.options;
   newConn._readyState = this._readyState;

From 447ff9e4d3a8e1a9e4987689c1f7cd037341c06d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 29 Apr 2020 14:17:07 +0200
Subject: [PATCH 0775/2348] upgrade mongodb to v3.5.7

---
 package.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 8b9051a2aac..13beb777585 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.5.6",
+    "mongodb": "3.5.7",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",
@@ -211,4 +211,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
\ No newline at end of file
+}

From 75631e6e1abde79398ecd68c236d646d5b771996 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 29 Apr 2020 15:42:06 +0200
Subject: [PATCH 0776/2348] make new connections config have higher priority

this change makes it so that the new config able to overwrite the default connection's config
---
 lib/drivers/node-mongodb-native/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index f7a59442310..3ed6c6cc6ca 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -58,7 +58,7 @@ NativeConnection.prototype.useDb = function(name, options) {
   newConn.collections = {};
   newConn.models = {};
   newConn.replica = this.replica;
-  newConn.config = Object.assign(newConn.config, this.base.connection.config);
+  newConn.config = Object.assign(this.base.connection.config, newConn.config);
   newConn.name = this.name;
   newConn.options = this.options;
   newConn._readyState = this._readyState;

From b5229651e79f7123cab9dd3915a6ed98f4e67c0c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 29 Apr 2020 17:09:52 +0200
Subject: [PATCH 0777/2348] refactor(getIndex): move collectIndexes definition
 after usage

---
 lib/helpers/schema/getIndexes.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index cc6db9e9d6b..ecfcabd50a6 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -14,7 +14,10 @@ module.exports = function getIndexes(schema) {
   const indexTypes = schema.constructor.indexTypes;
   const indexByName = new Map();
 
-  const collectIndexes = function(schema, prefix, baseSchema) {
+  collectIndexes(schema);
+  return indexes;
+
+  function collectIndexes(schema, prefix, baseSchema) {
     // Ignore infinitely nested schemas, if we've already seen this schema
     // along this path there must be a cycle
     if (schemaStack.has(schema)) {
@@ -107,10 +110,7 @@ module.exports = function getIndexes(schema) {
       });
       indexes = indexes.concat(schema._indexes);
     }
-  };
-
-  collectIndexes(schema);
-  return indexes;
+  }
 
   /*!
    * Checks for indexes added to subdocs using Schema.index().

From e0173848b12d1d6cb60bf44037448a2d3982a7f5 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 29 Apr 2020 17:10:07 +0200
Subject: [PATCH 0778/2348] test: repro #8895

---
 test/model.indexes.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 5de1a347da0..863a7b3935d 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -336,6 +336,22 @@ describe('model', function() {
       });
     });
 
+    it('creates descending indexes from schema definition(gh-8895)', function() {
+      return co(function*() {
+        const userSchema = new Schema({
+          name: { type: String, index: -1 }
+        });
+
+        const User = db.model('User', userSchema);
+
+        yield User.init();
+
+        const indexes = yield User.collection.getIndexes();
+
+        assert.ok(indexes['name_-1']);
+      });
+    });
+
     describe('auto creation', function() {
       it('can be disabled', function(done) {
         const schema = new Schema({ name: { type: String, index: true } });

From ad90d82b34ffb703a402cf75273666c46c5536af Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 29 Apr 2020 17:11:13 +0200
Subject: [PATCH 0779/2348] fix(model): allow adding desc. index on schema

---
 lib/helpers/schema/getIndexes.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index ecfcabd50a6..ce4286be45a 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -75,7 +75,8 @@ module.exports = function getIndexes(schema) {
           field[prefix + key] = 'text';
           delete options.text;
         } else {
-          field[prefix + key] = 1;
+          const isDescendingIndex = Number(index) === -1;
+          field[prefix + key] = isDescendingIndex ? -1 : 1;
         }
 
         delete options.type;

From 3c3505157f101c2d2d759fba8311be66b0112cc1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 30 Apr 2020 09:56:22 +0200
Subject: [PATCH 0780/2348] test: assert string descendeing index works

---
 test/model.indexes.test.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 863a7b3935d..41ff749f85e 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -339,7 +339,8 @@ describe('model', function() {
     it('creates descending indexes from schema definition(gh-8895)', function() {
       return co(function*() {
         const userSchema = new Schema({
-          name: { type: String, index: -1 }
+          name: { type: String, index: -1 },
+          address: { type: String, index: '-1' }
         });
 
         const User = db.model('User', userSchema);
@@ -349,6 +350,7 @@ describe('model', function() {
         const indexes = yield User.collection.getIndexes();
 
         assert.ok(indexes['name_-1']);
+        assert.ok(indexes['address_-1']);
       });
     });
 

From 9f23ddd420b93f4d36d2e0a831b638deb1955326 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 30 Apr 2020 10:05:59 +0200
Subject: [PATCH 0781/2348] allow no-prototype-builtins for eslint on v6.8.0
 no-prototype-builtins is enabled by default we're checking
 obj.hasOwnProperty(...) in many places in the codebase so in order to upgrade
 eslint, we'll allow obj.hasOwnProperty(...)

---
 package.json | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 0b7a170f4de..55ae3af423b 100644
--- a/package.json
+++ b/package.json
@@ -198,6 +198,7 @@
           "message": "Don't use Mocha's global context"
         }
       ],
+      "no-prototype-builtins": "off",
       "mocha-no-only/mocha-no-only": [
         "error"
       ]
@@ -207,4 +208,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
+}
\ No newline at end of file

From a5239509cb82f05db52866fe205ea61fae213bb8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Apr 2020 12:24:25 -0400
Subject: [PATCH 0782/2348] chore: release 5.9.11

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 13beb777585..b85c72b9e53 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.10",
+  "version": "5.9.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 619481bcdc411d46fb7331f1554d43725d56b6b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Apr 2020 12:37:59 -0400
Subject: [PATCH 0783/2348] chore: add 5.9.11 changelog

---
 History.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/History.md b/History.md
index 2d4aa45da6c..f2c21658727 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.9.11 / 2020-04-30
+===================
+ * fix: upgrade mongodb driver -> 3.5.7 #8842 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix: validate nested paths on Model.validate(...) #8848 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(populate): make doc.execPopulate(options) a shorthand for doc.populate(options) #8840 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(model): return validation errors when all docs are invalid & rawResult set #8853 [tusharf5](https://github.com/tusharf5)
+ * fix(schemaType): treat select: null or select: undefined as not specified #8850 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix: fix stream close event listener being called multiple times in Node 14 #8835 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(populate): handle `clone` with `lean` when setting a path to `null` #8807
+ * docs(faq): clarify setting paths under document arrays with `markModified()` #8854
+ * docs: fix race condition in creating connection for lambda #8845 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: add options.path for Model.populate(...) #8833 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: use ES6 classes for custom schema type example #8802
+
 5.9.10 / 2020-04-20
 ===================
  * fix: upgrade mongodb -> 3.5.6, bson -> 1.1.4 #8719

From 0abc001bf81e0898ac26ebad107fe50ec8ba4a1e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Apr 2020 12:46:07 -0400
Subject: [PATCH 0784/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index f2c6129228e..02ce5c6e52b 100644
--- a/index.pug
+++ b/index.pug
@@ -325,6 +325,9 @@ html(lang='en')
               <a href="https://alltimelist.com/">
                 <img class="sponsor" src="https://images.opencollective.com/all-time-list/b04f3ee/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://casinomatcher.com/ca/">
+                <img class="sponsor" src="https://images.opencollective.com/casinomatcher-com/31fbd0d/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 9e1bf4aade274b3b324414142b071fec8b98914f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 30 Apr 2020 18:49:51 +0200
Subject: [PATCH 0785/2348] correct changelog

---
 History.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f2c21658727..b7de17f54a3 100644
--- a/History.md
+++ b/History.md
@@ -2,7 +2,7 @@
 ===================
  * fix: upgrade mongodb driver -> 3.5.7 #8842 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
  * fix: validate nested paths on Model.validate(...) #8848 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
- * fix(populate): make doc.execPopulate(options) a shorthand for doc.populate(options) #8840 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(populate): make doc.execPopulate(options) a shorthand for doc.populate(options).execPopulate() #8840 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
  * fix(model): return validation errors when all docs are invalid & rawResult set #8853 [tusharf5](https://github.com/tusharf5)
  * fix(schemaType): treat select: null or select: undefined as not specified #8850 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
  * fix: fix stream close event listener being called multiple times in Node 14 #8835 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)

From de439a2a17cea2d15e2388294f8adc87eb6cef9f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Apr 2020 14:38:28 -0400
Subject: [PATCH 0786/2348] fix(schema): allow `once` as a path name re: #7958,
 #8869

---
 lib/schema.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index dab66f61338..d857b7ba636 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -572,7 +572,6 @@ reserved['prototype'] =
 // EventEmitter
 reserved.emit =
 reserved.on =
-reserved.once =
 reserved.listeners =
 reserved.removeListener =
 // document properties and functions

From bff1652580dbc22a46967002a08f2006c84a61f0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 30 Apr 2020 14:43:55 -0400
Subject: [PATCH 0787/2348] test: fix usage of assert.throws() for older Node
 versions

---
 test/schema.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 1c3a070a897..817ead0d0e5 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2415,19 +2415,19 @@ describe('schema', function() {
     it('throws errors on compiling schema with reserved key as a flat type', function() {
       const buildInvalidSchema = () => new Schema({ db: String });
 
-      assert.throws(buildInvalidSchema, { message: /`db` may not be used as a schema pathname/ });
+      assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
     });
 
     it('throws errors on compiling schema with reserved key as a nested object', function() {
       const buildInvalidSchema = () => new Schema({ db: { nested: String } });
 
-      assert.throws(buildInvalidSchema, { message: /`db` may not be used as a schema pathname/ });
+      assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
     });
 
     it('throws errors on compiling schema with reserved key as a nested array', function() {
       const buildInvalidSchema = () => new Schema({ db: [{ nested: String }] });
 
-      assert.throws(buildInvalidSchema, { message: /`db` may not be used as a schema pathname/ });
+      assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
     });
   });
 });

From 32f75e904e9caefacadeeb1ab356d58c0fe36a6f Mon Sep 17 00:00:00 2001
From: Calvin Huang <c@lvin.me>
Date: Thu, 30 Apr 2020 13:38:50 -0700
Subject: [PATCH 0788/2348] allow mongodb options in distinct

---
 lib/query.js | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index de4195879ee..f0c783a5962 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2452,10 +2452,10 @@ Query.prototype.countDocuments = function(conditions, callback) {
 };
 
 /**
- * Thunk around findOne()
+ * Thunk around distinct()
  *
  * @param {Function} [callback]
- * @see findOne http://docs.mongodb.org/manual/reference/method/db.collection.findOne/
+ * @see distinct http://docs.mongodb.org/manual/reference/method/db.collection.distinct/
  * @api private
  */
 
@@ -2467,9 +2467,11 @@ Query.prototype.__distinct = wrapThunk(function __distinct(callback) {
     return null;
   }
 
+  const options = this._optionsForExec();
+
   // don't pass in the conditions because we already merged them in
   this._collection.collection.
-    distinct(this._distinct, this._conditions, callback);
+    distinct(this._distinct, this._conditions, options, callback);
 });
 
 /**

From 56e928149e15b432baf7f77744823d648703f774 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 1 May 2020 15:19:47 +0200
Subject: [PATCH 0789/2348] avoid new connection config mutating original
 config

---
 lib/drivers/node-mongodb-native/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index 3ed6c6cc6ca..8041a881620 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -58,7 +58,7 @@ NativeConnection.prototype.useDb = function(name, options) {
   newConn.collections = {};
   newConn.models = {};
   newConn.replica = this.replica;
-  newConn.config = Object.assign(this.base.connection.config, newConn.config);
+  newConn.config = Object.assign({}, this.base.connection.config, newConn.config);
   newConn.name = this.name;
   newConn.options = this.options;
   newConn._readyState = this._readyState;

From 661d0d734558663ac3c3d715862392616c8de37b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 1 May 2020 16:13:44 +0200
Subject: [PATCH 0790/2348] docs: add flattenMaps and aliases to
 Document#toObject()

---
 lib/document.js | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d50f56d6e18..742170aa488 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3067,11 +3067,13 @@ Document.prototype.$toObject = function(options, json) {
  * ####Options:
  *
  * - `getters` apply all getters (path and virtual getters), defaults to false
+ * - `aliases` apply all aliases `if virtuals=true`, defaults to true
  * - `virtuals` apply virtual getters (can override `getters` option), defaults to false
- * - `minimize` remove empty objects (defaults to true)
+ * - `minimize` remove empty objects, defaults to true
  * - `transform` a transform function to apply to the resulting document before returning
- * - `depopulate` depopulate any populated paths, replacing them with their original refs (defaults to false)
- * - `versionKey` whether to include the version key (defaults to true)
+ * - `depopulate` depopulate any populated paths, replacing them with their original refs, defaults to false
+ * - `versionKey` whether to include the version key, defaults to true
+ * - `flattenMaps` convert Maps to POJOs. Useful if you want to JSON.stringify() the result of toObject(), defaults to false
  *
  * ####Getters/Virtuals
  *

From 87cec18543a84ed51d87ccac44a7aa87c2c12487 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 1 May 2020 16:14:37 +0200
Subject: [PATCH 0791/2348] fix formatting

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 742170aa488..4401126ac82 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3067,7 +3067,7 @@ Document.prototype.$toObject = function(options, json) {
  * ####Options:
  *
  * - `getters` apply all getters (path and virtual getters), defaults to false
- * - `aliases` apply all aliases `if virtuals=true`, defaults to true
+ * - `aliases` apply all aliases if `virtuals=true`, defaults to true
  * - `virtuals` apply virtual getters (can override `getters` option), defaults to false
  * - `minimize` remove empty objects, defaults to true
  * - `transform` a transform function to apply to the resulting document before returning

From d5f6b2b3b85e9c128510b2d1a1f05a1c666640fd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 1 May 2020 10:23:34 -0400
Subject: [PATCH 0792/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 02ce5c6e52b..6772109f268 100644
--- a/index.pug
+++ b/index.pug
@@ -328,6 +328,9 @@ html(lang='en')
               <a href="https://casinomatcher.com/ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinomatcher-com/31fbd0d/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://netticasinohex.com/kasinot/">
+                <img class="sponsor" src="https://images.opencollective.com/netticasinohex-com/71d7417/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 4a1a7434222a03470f2d23796d507b3f7d158e92 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 2 May 2020 14:02:58 +0200
Subject: [PATCH 0793/2348] fix(docs): fix broken references to
 Mongoose#Document API

---
 docs/documents.pug | 2 +-
 docs/guide.pug     | 2 +-
 lib/browser.js     | 2 +-
 lib/index.js       | 2 +-
 lib/model.js       | 2 +-
 lib/query.js       | 2 +-
 6 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/docs/documents.pug b/docs/documents.pug
index b452fcce5ed..a6534660981 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -18,7 +18,7 @@ block content
       <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
     </div>
 
-    Mongoose [documents](./api.html#document-js) represent a one-to-one mapping
+    Mongoose [documents](./api/document.html) represent a one-to-one mapping
     to documents as stored in MongoDB. Each document is an instance of its
     [Model](./models.html).
 
diff --git a/docs/guide.pug b/docs/guide.pug
index 706700277e7..39b04409d11 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -156,7 +156,7 @@ block content
     <h3 id="methods"><a href="#methods">Instance methods</a></h3>
 
     Instances of `Models` are [documents](./documents.html). Documents have
-    many of their own [built-in instance methods](./api.html#document-js).
+    many of their own [built-in instance methods](./api/document.html).
     We may also define our own custom document instance methods.
 
     ```javascript
diff --git a/lib/browser.js b/lib/browser.js
index 0a65dd78b62..b151d51b674 100644
--- a/lib/browser.js
+++ b/lib/browser.js
@@ -116,7 +116,7 @@ exports.SchemaType = require('./schematype.js');
 exports.utils = require('./utils.js');
 
 /**
- * The Mongoose browser [Document](#document-js) constructor.
+ * The Mongoose browser [Document](/api/document.html) constructor.
  *
  * @method Document
  * @api public
diff --git a/lib/index.js b/lib/index.js
index 8db4da98e2d..8c7c9f0aa90 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -903,7 +903,7 @@ Mongoose.prototype.PromiseProvider = PromiseProvider;
 Mongoose.prototype.Model = Model;
 
 /**
- * The Mongoose [Document](#document-js) constructor.
+ * The Mongoose [Document](/api/document.html) constructor.
  *
  * @method Document
  * @api public
diff --git a/lib/model.js b/lib/model.js
index 4c19b475b0a..cc9a7851232 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -88,7 +88,7 @@ const saveToObjectOptions = Object.assign({}, internalToObjectOptions, {
  * @param {Object} doc values for initial set
  * @param [fields] optional object containing the fields that were selected in the query which returned this document. You do **not** need to set this parameter to ensure Mongoose handles your [query projection](./api.html#query_Query-select).
  * @param {Boolean} [skipId=false] optional boolean. If true, mongoose doesn't add an `_id` field to the document.
- * @inherits Document http://mongoosejs.com/docs/api.html#document-js
+ * @inherits Document http://mongoosejs.com/docs/api/document.html
  * @event `error`: If listening to this event, 'error' is emitted when a document was saved without passing a callback and an `error` occurred. If not listening, the event bubbles to the connection used to create this Model.
  * @event `index`: Emitted after `Model#ensureIndexes` completes. If an error occurred it is passed with the event.
  * @event `index-single-start`: Emitted when an individual index starts within `Model#ensureIndexes`. The fields and options being used to build the index are also passed with the event.
diff --git a/lib/query.js b/lib/query.js
index de4195879ee..d1dbdb4b723 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1640,7 +1640,7 @@ const setSafe = util.deprecate(function setSafe(options, safe) {
  * Sets the lean option.
  *
  * Documents returned from queries with the `lean` option enabled are plain
- * javascript objects, not [Mongoose Documents](#document-js). They have no
+ * javascript objects, not [Mongoose Documents](/api/document.html). They have no
  * `save` method, getters/setters, virtuals, or other Mongoose features.
  *
  * ####Example:

From 3065b19e34a3c4ccf37e0645ef2d6e50984b79ea Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 2 May 2020 14:42:15 +0200
Subject: [PATCH 0794/2348] fix(docs): use mongoose.model instead of
 this.model(...) in hooks

---
 examples/geospatial/person.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/geospatial/person.js b/examples/geospatial/person.js
index ccfbce786c8..9f692320bb5 100644
--- a/examples/geospatial/person.js
+++ b/examples/geospatial/person.js
@@ -19,7 +19,7 @@ module.exports = function() {
 
   // define a method to find the closest person
   PersonSchema.methods.findClosest = function(cb) {
-    return this.model('Person').find({
+    return mongoose.model('Person').find({
       loc: { $nearSphere: this.loc },
       name: { $ne: this.name }
     }).limit(1).exec(cb);

From 560ef562d337166bd3c7ce29e4955d96b914fe83 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 2 May 2020 14:43:19 +0200
Subject: [PATCH 0795/2348] fix(docs): use mongoose.model instead of
 this.model(...) in hooks

---
 docs/3.0.x/docs/guide.jade | 2 +-
 docs/3.1.x/docs/guide.jade | 2 +-
 docs/3.2.x/docs/guide.jade | 2 +-
 docs/3.3.x/docs/guide.jade | 2 +-
 docs/guide.pug             | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/docs/3.0.x/docs/guide.jade b/docs/3.0.x/docs/guide.jade
index 69f5c6e4aa5..449dfdfeea5 100644
--- a/docs/3.0.x/docs/guide.jade
+++ b/docs/3.0.x/docs/guide.jade
@@ -90,7 +90,7 @@ block content
     var animalSchema = new Schema({ name: String, type: String });
 
     animalSchema.methods.findSimilarTypes = function (cb) {
-      return this.model('Animal').find({ type: this.type }, cb);
+      return mongoose.model('Animal').find({ type: this.type }, cb);
     }
   p
     | Now all of our 
diff --git a/docs/3.1.x/docs/guide.jade b/docs/3.1.x/docs/guide.jade
index 2801c114eb1..318475181e9 100644
--- a/docs/3.1.x/docs/guide.jade
+++ b/docs/3.1.x/docs/guide.jade
@@ -90,7 +90,7 @@ block content
     var animalSchema = new Schema({ name: String, type: String });
 
     animalSchema.methods.findSimilarTypes = function (cb) {
-      return this.model('Animal').find({ type: this.type }, cb);
+      return mongoose.model('Animal').find({ type: this.type }, cb);
     }
   p
     | Now all of our 
diff --git a/docs/3.2.x/docs/guide.jade b/docs/3.2.x/docs/guide.jade
index 445f123bb08..8535d4ea124 100644
--- a/docs/3.2.x/docs/guide.jade
+++ b/docs/3.2.x/docs/guide.jade
@@ -90,7 +90,7 @@ block content
     var animalSchema = new Schema({ name: String, type: String });
 
     animalSchema.methods.findSimilarTypes = function (cb) {
-      return this.model('Animal').find({ type: this.type }, cb);
+      return mongoose.model('Animal').find({ type: this.type }, cb);
     }
   p
     | Now all of our 
diff --git a/docs/3.3.x/docs/guide.jade b/docs/3.3.x/docs/guide.jade
index b1878f83e9d..290e99123e1 100644
--- a/docs/3.3.x/docs/guide.jade
+++ b/docs/3.3.x/docs/guide.jade
@@ -90,7 +90,7 @@ block content
     var animalSchema = new Schema({ name: String, type: String });
 
     animalSchema.methods.findSimilarTypes = function (cb) {
-      return this.model('Animal').find({ type: this.type }, cb);
+      return mongoose.model('Animal').find({ type: this.type }, cb);
     }
   p
     | Now all of our 
diff --git a/docs/guide.pug b/docs/guide.pug
index 39b04409d11..442496d09cc 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -165,7 +165,7 @@ block content
 
       // assign a function to the "methods" object of our animalSchema
       animalSchema.methods.findSimilarTypes = function(cb) {
-        return this.model('Animal').find({ type: this.type }, cb);
+        return mongoose.model('Animal').find({ type: this.type }, cb);
       };
     ```
 

From d6d57ff0495ef1f0a8dac65fc44926baf3987be6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 2 May 2020 15:38:24 +0200
Subject: [PATCH 0796/2348] docs(populate): make limit vs. perDocumentLimit its
 own section

---
 docs/populate.pug | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/populate.pug b/docs/populate.pug
index 152d1909c32..da0c609b11c 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -262,6 +262,8 @@ block content
       exec();
     ```
 
+    <h3 id="limit-vs-perDocumentLimit"><a href="#limit-vs-perDocumentLimit">limit vs. perDocumentLimit</a></h3>
+
     Populate does support a `limit` option, however, it currently
     does **not** limit on a per-document basis. For example, suppose
     you have 2 stories:

From 018cef0663d24120a0cebbdf8f8409d0d95fdc45 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 2 May 2020 15:38:47 +0200
Subject: [PATCH 0797/2348] docs(faq): add limit vs. perDocumentLimit FAQ for
 populate(...)

---
 docs/faq.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docs/faq.pug b/docs/faq.pug
index 3dfaaaa3218..c20cae329dd 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -449,6 +449,12 @@ block content
 
     **A**. Because the Map eventually gets stored in MongoDB where the keys must be strings.
 
+    <hr id="limit-vs-perDocumentLimit" />
+
+    <a href="#limit-vs-perDocumentLimit">**Q**</a>. I am using `Model.find(...).populate(...)` with the `limit` option, but getting fewer results than the limit. What gives?
+
+    **A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the [perDocumentLimit](/api/populate.html##limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in mind that populate() will execute a separate query for each document.
+
     <hr id="add_something" />
 
     **Something to add?**

From bea601cba18141630410cff33f76249be2e60565 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 16:30:41 -0400
Subject: [PATCH 0798/2348] test(document): repro #8888

---
 test/document.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 060fc092dce..19b686d8668 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8911,4 +8911,16 @@ describe('document', function() {
       assert.equal(updatedDoc.array[0][0].value, 'world');
     });
   });
+
+  it('reports array cast error with index (gh-8888)', function() {
+    const schema = Schema({ test: [ Number ] },
+      { autoIndex: false, autoCreate: false });
+    const Test = db.model('test', schema);
+
+    const t = new Test({ test: [1, 'world'] });
+    const err = t.validateSync();
+    assert.ok(err);
+    assert.ok(err.errors);
+    assert.ok(err.errors['test.1']);
+  });
 });

From 5cca9d655c0714ba7aaadf5ded668b293d293285 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 16:33:57 -0400
Subject: [PATCH 0799/2348] fix(document): report cast error on array elements
 with array index instead of just being a cast error for the whole array

Fix #8888
---
 lib/document.js       |  6 ++++++
 lib/schematype.js     | 14 +++++++++++---
 test/document.test.js |  3 ++-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4401126ac82..0c161c8b6ec 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1234,6 +1234,12 @@ Document.prototype.$set = function $set(path, val, type, options) {
   } catch (e) {
     if (e instanceof MongooseError.StrictModeError && e.isImmutableError) {
       this.invalidate(path, e);
+    } else if (e instanceof MongooseError.CastError) {
+      this.invalidate(e.path, e);
+      if (e.$originalErrorPath) {
+        this.invalidate(path,
+          new MongooseError.CastError(schema.instance, val, path, e.$originalErrorPath));
+      }
     } else {
       this.invalidate(path,
         new MongooseError.CastError(schema.instance, val, path, e));
diff --git a/lib/schematype.js b/lib/schematype.js
index 6c30cc56906..9cb62caf37d 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -989,12 +989,20 @@ SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
     v = setter.call(scope, v, this);
   }
 
-
   if (Array.isArray(v) && caster && caster.setters) {
     const newVal = [];
 
-    for (const value of v) {
-      newVal.push(caster.applySetters(value, scope, init, priorVal));
+    for (let i = 0; i < v.length; ++i) {
+      const value = v[i];
+      try {
+        newVal.push(caster.applySetters(value, scope, init, priorVal));
+      } catch (err) {
+        if (err instanceof MongooseError.CastError) {
+          err.$originalErrorPath = err.path;
+          err.path = err.path + '.' + i;
+        }
+        throw err;
+      }
     }
     v = newVal;
   }
diff --git a/test/document.test.js b/test/document.test.js
index 19b686d8668..3d8c881a93a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8913,7 +8913,7 @@ describe('document', function() {
   });
 
   it('reports array cast error with index (gh-8888)', function() {
-    const schema = Schema({ test: [ Number ] },
+    const schema = Schema({ test: [Number] },
       { autoIndex: false, autoCreate: false });
     const Test = db.model('test', schema);
 
@@ -8921,6 +8921,7 @@ describe('document', function() {
     const err = t.validateSync();
     assert.ok(err);
     assert.ok(err.errors);
+    assert.ok(err.errors['test']);
     assert.ok(err.errors['test.1']);
   });
 });

From 5b35f206fdd6f19c3711efb174747db45b312b23 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 16:42:07 -0400
Subject: [PATCH 0800/2348] test: fix tests re: #8888

---
 lib/schema/buffer.js | 6 +++---
 lib/schema/number.js | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 81f03009177..631d18fcb3d 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -142,7 +142,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
     if (Buffer.isBuffer(value)) {
       return value;
     } else if (!utils.isObject(value)) {
-      throw new CastError('buffer', value, this.path, null, this);
+      throw new CastError('Buffer', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -178,7 +178,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
   if (value instanceof Binary) {
     ret = new MongooseBuffer(value.value(true), [this.path, doc]);
     if (typeof value.sub_type !== 'number') {
-      throw new CastError('buffer', value, this.path, null, this);
+      throw new CastError('Buffer', value, this.path, null, this);
     }
     ret._subtype = value.sub_type;
     return ret;
@@ -204,7 +204,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
     return ret;
   }
 
-  throw new CastError('buffer', value, this.path, null, this);
+  throw new CastError('Buffer', value, this.path, null, this);
 };
 
 /**
diff --git a/lib/schema/number.js b/lib/schema/number.js
index d868b4e581b..0b532bc29cc 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -357,7 +357,7 @@ SchemaNumber.prototype.cast = function(value, doc, init) {
     if (typeof value === 'number') {
       return value;
     } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('number', value, this.path, null, this);
+      throw new CastError('Number', value, this.path, null, this);
     }
 
     // Handle the case where user directly sets a populated
@@ -381,7 +381,7 @@ SchemaNumber.prototype.cast = function(value, doc, init) {
   try {
     return castNumber(val);
   } catch (err) {
-    throw new CastError('number', val, this.path, err, this);
+    throw new CastError('Number', val, this.path, err, this);
   }
 };
 

From ace85cf514fb8c43b195d486db464d90cd87f766 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 16:48:52 -0400
Subject: [PATCH 0801/2348] test: fix more tests re: #8888

---
 test/cast.test.js             | 2 +-
 test/es-next/cast.test.es6.js | 2 +-
 test/model.querying.test.js   | 2 +-
 test/schema.test.js           | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/cast.test.js b/test/cast.test.js
index ebc8a4b6f58..6adfa681b17 100644
--- a/test/cast.test.js
+++ b/test/cast.test.js
@@ -88,7 +88,7 @@ describe('cast: ', function() {
       const numbers = [123, 456, 'asfds'];
       assert.throws(function() {
         cast(schema, { x: numbers });
-      }, /Cast to number failed for value "asfds"/);
+      }, /Cast to Number failed for value "asfds"/);
       done();
     });
   });
diff --git a/test/es-next/cast.test.es6.js b/test/es-next/cast.test.es6.js
index 2a400472670..92c76b6d05c 100644
--- a/test/es-next/cast.test.es6.js
+++ b/test/es-next/cast.test.es6.js
@@ -87,7 +87,7 @@ describe('Cast Tutorial', function() {
     err.message;
     // acquit:ignore:start
     assert.ok(err instanceof mongoose.CastError);
-    assert.equal(err.message, 'Cast to number failed for value "not a ' +
+    assert.equal(err.message, 'Cast to Number failed for value "not a ' +
       'number" at path "age" for model "Character"');
     // acquit:ignore:end
   });
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 047db6667f0..79e6bfad05d 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -1806,7 +1806,7 @@ describe('model: querying:', function() {
           assert.equal(rb.block.toString('utf8'), 'buffer shtuffs are neat');
 
           Test.findOne({ block: /buffer/i }, function(err) {
-            assert.equal(err.message, 'Cast to buffer failed for value ' +
+            assert.equal(err.message, 'Cast to Buffer failed for value ' +
               '"/buffer/i" at path "block" for model "Test"');
             Test.findOne({ block: [195, 188, 98, 101, 114] }, function(err, rb) {
               assert.ifError(err);
diff --git a/test/schema.test.js b/test/schema.test.js
index 817ead0d0e5..0a1e00f6b80 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -441,7 +441,7 @@ describe('schema', function() {
         threw = true;
         assert.equal(error.name, 'CastError');
         assert.equal(error.message,
-          'Cast to [[number]] failed for value "[["abcd"]]" at path "nums"');
+          'Cast to [[Number]] failed for value "[["abcd"]]" at path "nums"');
       }
       assert.ok(threw);
 

From 3ce7c3a3dc83f1014f5de37bdb1d56ee5458f9d4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 17:12:13 -0400
Subject: [PATCH 0802/2348] test(document): repro #8829

---
 test/document.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 3d8c881a93a..5d16f95dba6 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8924,4 +8924,21 @@ describe('document', function() {
     assert.ok(err.errors['test']);
     assert.ok(err.errors['test.1']);
   });
+
+  it('sets defaults if setting nested path to empty object with minimize false (gh-8829)', function() {
+    const cartSchema = Schema({
+      _id: 'String',
+      item: {
+        name: { type: 'String', default: 'Default Name' },
+      }
+    },
+    { minimize: false });
+    const Test = db.model('Test', cartSchema);
+  
+    const doc = new Test({ _id: 'foobar', item: {} });
+
+    return doc.save().
+      then(() => Test.collection.findOne()).
+      then(doc => assert.equal(doc.item.name, 'Default Name'));  
+  });
 });

From ff60457d72d98c2a667f82a979679eb2acb10a1a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 17:12:23 -0400
Subject: [PATCH 0803/2348] fix(document): set defaults if setting nested path
 to empty object with `minimize: false`

Fix #8829
---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 0c161c8b6ec..43fef6d810e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -907,7 +907,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
       // `_skipMinimizeTopLevel` is because we may have deleted the top-level
       // nested key to ensure key order.
       const _skipMinimizeTopLevel = get(options, '_skipMinimizeTopLevel', false);
-      if (len === 0 && (!this.schema.options.minimize || _skipMinimizeTopLevel)) {
+      if (len === 0 && _skipMinimizeTopLevel) {
         delete options._skipMinimizeTopLevel;
         if (val) {
           this.$set(val, {});

From 17b7988ec186c38c983478ea22a356d397ce324a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 17:19:48 -0400
Subject: [PATCH 0804/2348] style: fix lint

---
 test/document.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 5d16f95dba6..22f3059603f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8929,16 +8929,16 @@ describe('document', function() {
     const cartSchema = Schema({
       _id: 'String',
       item: {
-        name: { type: 'String', default: 'Default Name' },
+        name: { type: 'String', default: 'Default Name' }
       }
     },
     { minimize: false });
     const Test = db.model('Test', cartSchema);
-  
+
     const doc = new Test({ _id: 'foobar', item: {} });
 
     return doc.save().
       then(() => Test.collection.findOne()).
-      then(doc => assert.equal(doc.item.name, 'Default Name'));  
+      then(doc => assert.equal(doc.item.name, 'Default Name'));
   });
 });

From 2bea45372a2bb8c19c6f8d27f004e43df9906ea6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 May 2020 17:21:53 -0400
Subject: [PATCH 0805/2348] chore: update opencollective sponsors

---
 index.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.pug b/index.pug
index 6772109f268..40a5bb1eb40 100644
--- a/index.pug
+++ b/index.pug
@@ -331,6 +331,12 @@ html(lang='en')
               <a href="https://netticasinohex.com/kasinot/">
                 <img class="sponsor" src="https://images.opencollective.com/netticasinohex-com/71d7417/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://casinohex.at/online-casinos/">
+                <img class="sponsor" src="https://images.opencollective.com/casinohex-at/8e06f0e/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://casinohex.se/online-casinon/">
+                <img class="sponsor" src="https://images.opencollective.com/casinohex-se/795919b/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 54dd5cbf9a69a6079f1d88afceb480cf6fa87476 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 3 May 2020 15:44:32 -0400
Subject: [PATCH 0806/2348] fix(connection): throw more helpful error in case
 of IP whitelisting issue with Atlas

Fix #8846
---
 lib/error/serverSelection.js              | 13 ++++++++++++-
 lib/helpers/topology/allServersUnknown.js | 11 +++++++++++
 lib/helpers/topology/isAtlas.js           | 11 +++++++++++
 3 files changed, 34 insertions(+), 1 deletion(-)
 create mode 100644 lib/helpers/topology/allServersUnknown.js
 create mode 100644 lib/helpers/topology/isAtlas.js

diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index 7e6a1281e80..13f96b753f6 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -5,6 +5,8 @@
 'use strict';
 
 const MongooseError = require('./mongooseError');
+const allServersUnknown = require('../helpers/topology/allServersUnknown');
+const isAtlas = require('../helpers/topology/isAtlas');
 
 /**
  * MongooseServerSelectionError constructor
@@ -36,8 +38,17 @@ MongooseServerSelectionError.prototype.constructor = MongooseError;
  * ignore
  */
 
+const atlasMessage = 'Could not connect to any servers in your MongoDB Atlas ' +
+  'cluster. Make sure your current IP address is on your Atlas cluster\'s IP ' +
+  'whitelist: https://docs.atlas.mongodb.com/security-whitelist/.';
+
 MongooseServerSelectionError.prototype.assimilateError = function(err) {
-  this.message = err.message;
+  const reason = err.reason;
+  // Special message for a case that is likely due to IP whitelisting issues.
+  const isAtlasWhitelistError = isAtlas(reason) && allServersUnknown(reason);
+  this.message = isAtlasWhitelistError ?
+    atlasMessage :
+    err.message;
   Object.assign(this, err, {
     name: 'MongooseServerSelectionError'
   });
diff --git a/lib/helpers/topology/allServersUnknown.js b/lib/helpers/topology/allServersUnknown.js
new file mode 100644
index 00000000000..f85b7279184
--- /dev/null
+++ b/lib/helpers/topology/allServersUnknown.js
@@ -0,0 +1,11 @@
+'use strict';
+
+module.exports = function allServersUnknown(topologyDescription) {
+  if (topologyDescription == null ||
+      topologyDescription.constructor.name !== 'TopologyDescription') {
+    return false;
+  }
+
+  return Array.from(topologyDescription.servers.values()).
+    every(server => server.type === 'Unknown');
+};
\ No newline at end of file
diff --git a/lib/helpers/topology/isAtlas.js b/lib/helpers/topology/isAtlas.js
new file mode 100644
index 00000000000..b7647fd5abb
--- /dev/null
+++ b/lib/helpers/topology/isAtlas.js
@@ -0,0 +1,11 @@
+'use strict';
+
+module.exports = function isAtlas(topologyDescription) {
+  if (topologyDescription == null ||
+    topologyDescription.constructor.name !== 'TopologyDescription') {
+    return false;
+  }
+
+  return Array.from(topologyDescription.servers.keys()).
+    every(host => host.endsWith('.mongodb.net:27017'));
+};
\ No newline at end of file

From 20ee6389a6e7667e1b36c38b0748a79bf68f2c3c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 04:06:31 +0200
Subject: [PATCH 0807/2348] test: repro #8923

---
 test/model.field.selection.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/model.field.selection.test.js b/test/model.field.selection.test.js
index 1d63dcac7c8..2d4c8e56b54 100644
--- a/test/model.field.selection.test.js
+++ b/test/model.field.selection.test.js
@@ -539,4 +539,21 @@ describe('model field selection', function() {
       assert.equal(product.name, 'Computer');
     });
   });
+
+  it('selecting with `false` instead of `0` doesn\'t overwrite schema `select: false` (gh-8923)', function() {
+    return co(function*() {
+      const userSchema = new Schema({
+        name: { type: String, select: false },
+        age: { type: Number }
+      });
+
+      const User = db.model('User', userSchema);
+
+      yield User.create({ name: 'Hafez', age: 25 });
+
+      const user = yield User.findOne().select({ age: false });
+
+      assert.ok(!user.name);
+    });
+  });
 });
\ No newline at end of file

From 6eda0bba5d7633294fc22e515ba8e7bd5f5e1961 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 04:08:33 +0200
Subject: [PATCH 0808/2348] fix(query): query.select({ field: false }) should
 not overwrite schema selection options

---
 lib/queryhelpers.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 13d6ff83590..0089ca9c330 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -135,7 +135,7 @@ exports.applyPaths = function applyPaths(fields, schema) {
       if (!isDefiningProjection(field)) {
         continue;
       }
-      exclude = field === 0;
+      exclude = field === 0 || field === false;
       break;
     }
   }

From 2f2e535cb0e63a89659890b90868c541a9f4a3d2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 04:16:49 +0200
Subject: [PATCH 0809/2348] prove that test fails

---
 lib/queryhelpers.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 0089ca9c330..13d6ff83590 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -135,7 +135,7 @@ exports.applyPaths = function applyPaths(fields, schema) {
       if (!isDefiningProjection(field)) {
         continue;
       }
-      exclude = field === 0 || field === false;
+      exclude = field === 0;
       break;
     }
   }

From 406b95826dd3456808db9c16a62414f705bbad91 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 04:21:25 +0200
Subject: [PATCH 0810/2348] Revert "prove that test fails"

This reverts commit 2f2e535cb0e63a89659890b90868c541a9f4a3d2.
---
 lib/queryhelpers.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 13d6ff83590..0089ca9c330 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -135,7 +135,7 @@ exports.applyPaths = function applyPaths(fields, schema) {
       if (!isDefiningProjection(field)) {
         continue;
       }
-      exclude = field === 0;
+      exclude = field === 0 || field === false;
       break;
     }
   }

From ce4431096979625aae6e4f699a802529debbe198 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 06:19:40 +0200
Subject: [PATCH 0811/2348] test: repro #8924

---
 test/docs/discriminators.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index a0f210cf64f..77f95a69da3 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -419,4 +419,25 @@ describe('discriminator docs', function () {
     assert.equal(doc.shape.side, 10);
     // acquit:ignore:end
   });
+  
+  it('attempting to populate on base model a virtual path defined on discriminator does not throw an error (gh-8924)', function () {
+    return co(function* () {
+      const User = db.model('User', {});
+      const Post = db.model('Post', {});
+      
+      const userWithPostSchema = new Schema({ postId: Schema.ObjectId });
+      
+      userWithPostSchema.virtual('post', { ref: 'Post', localField: 'postId', foreignField: '_id' });
+      
+      const UserWithPost = User.discriminator('UserWithPost', userWithPostSchema);
+      
+      const post = yield Post.create({});
+      
+      yield UserWithPost.create({ postId: post._id });
+      
+      const user = yield User.findOne().populate({ path: 'post' });
+      
+      assert.ok(user.postId);
+    })
+  });
 });

From 97c7a83ed386f0f828a8989e3cc30837f7580dbc Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 06:23:45 +0200
Subject: [PATCH 0812/2348] fix(model): fix throwing error when populating
 virtual path defined on child discriminator

---
 lib/helpers/populate/getModelsMapForPopulate.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 0411f145322..79902c11302 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -279,7 +279,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           model: Model
         };
 
-        if (isVirtual && virtual.options && virtual.options.options) {
+        if (isVirtual && get(virtual, 'options.options')) {
           currentOptions.options = utils.clone(virtual.options.options);
         }
         utils.merge(currentOptions, options);

From b5e1333066b162200a9ecc34bf5996e2c80368ca Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 06:31:26 +0200
Subject: [PATCH 0813/2348] move test to correct file and revert fix

---
 .../populate/getModelsMapForPopulate.js       |  2 +-
 test/docs/discriminators.test.js              | 21 -------------------
 test/model.discriminator.test.js              | 21 +++++++++++++++++++
 3 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 79902c11302..0411f145322 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -279,7 +279,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           model: Model
         };
 
-        if (isVirtual && get(virtual, 'options.options')) {
+        if (isVirtual && virtual.options && virtual.options.options) {
           currentOptions.options = utils.clone(virtual.options.options);
         }
         utils.merge(currentOptions, options);
diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index 77f95a69da3..a0f210cf64f 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -419,25 +419,4 @@ describe('discriminator docs', function () {
     assert.equal(doc.shape.side, 10);
     // acquit:ignore:end
   });
-  
-  it('attempting to populate on base model a virtual path defined on discriminator does not throw an error (gh-8924)', function () {
-    return co(function* () {
-      const User = db.model('User', {});
-      const Post = db.model('Post', {});
-      
-      const userWithPostSchema = new Schema({ postId: Schema.ObjectId });
-      
-      userWithPostSchema.virtual('post', { ref: 'Post', localField: 'postId', foreignField: '_id' });
-      
-      const UserWithPost = User.discriminator('UserWithPost', userWithPostSchema);
-      
-      const post = yield Post.create({});
-      
-      yield UserWithPost.create({ postId: post._id });
-      
-      const user = yield User.findOne().populate({ path: 'post' });
-      
-      assert.ok(user.postId);
-    })
-  });
 });
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 399eed460c7..4bf886e5f5b 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1556,4 +1556,25 @@ describe('model', function() {
       done();
     });
   });
+
+  it('attempting to populate on base model a virtual path defined on discriminator does not throw an error (gh-8924)', function () {
+    return co(function* () {
+      const User = db.model('User', {});
+      const Post = db.model('Post', {});
+      
+      const userWithPostSchema = new Schema({ postId: Schema.ObjectId });
+      
+      userWithPostSchema.virtual('post', { ref: 'Post', localField: 'postId', foreignField: '_id' });
+      
+      const UserWithPost = User.discriminator('UserWithPost', userWithPostSchema);
+      
+      const post = yield Post.create({});
+      
+      yield UserWithPost.create({ postId: post._id });
+      
+      const user = yield User.findOne().populate({ path: 'post' });
+      
+      assert.ok(user.postId);
+    })
+  });
 });

From 55073b508835679febd41df49fd96fa143084707 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 4 May 2020 06:33:59 +0200
Subject: [PATCH 0814/2348] add fix again for virtual.options.options access

---
 lib/helpers/populate/getModelsMapForPopulate.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 0411f145322..79902c11302 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -279,7 +279,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           model: Model
         };
 
-        if (isVirtual && virtual.options && virtual.options.options) {
+        if (isVirtual && get(virtual, 'options.options')) {
           currentOptions.options = utils.clone(virtual.options.options);
         }
         utils.merge(currentOptions, options);

From ba0f19912b3fe5820acfd91c971cb52a3db6df15 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 4 May 2020 17:54:36 -0400
Subject: [PATCH 0815/2348] chore: release 5.9.12

---
 History.md   | 16 ++++++++++++++++
 package.json |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index b7de17f54a3..0fb455e2e62 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,19 @@
+5.9.12 / 2020-05-04
+===================
+ * fix(document): report cast error on array elements with array index instead of just being a cast error for the whole array #8888
+ * fix(connection): throw more helpful error in case of IP whitelisting issue with Atlas #8846
+ * fix(schema): throw error on schema with reserved key with type of object #8869 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(connection): inherit config for useDB from default connection #8267 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(query): set mongodb options for `distinct()` #8906 [clhuang](https://github.com/clhuang)
+ * fix(schema): allow adding descending indexes on schema #8895 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(document): set defaults if setting nested path to empty object with `minimize: false` #8829
+ * fix(populate): check discriminator existence before accessing schema in getModelsMapForPopulate #8837 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: fix broken references to Mongoose#Document API, and prefer mongoose.model(...) over Document#model(...) #8914 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(model): adds options.limit to Model.insertMany(...) #8864 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: add flattenMaps and aliases to Document#toObject() #8901 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(model): add options.overwrite to findOneAndUpdate #8865 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(populate+faq): separate limit-vs-perDocumentLimit into its own section, add FAQ for populate and limit #8917 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.9.11 / 2020-04-30
 ===================
  * fix: upgrade mongodb driver -> 3.5.7 #8842 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 6eaf65e1c32..75a5711693f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.11",
+  "version": "5.9.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From fe67322af41367e82953e8702504c6cda3f9df26 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 5 May 2020 17:39:59 +0200
Subject: [PATCH 0816/2348] docs(faq): fix broken reference in limit vs
 perDocumentLimit

---
 docs/faq.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index c20cae329dd..fddf5296f15 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -453,7 +453,7 @@ block content
 
     <a href="#limit-vs-perDocumentLimit">**Q**</a>. I am using `Model.find(...).populate(...)` with the `limit` option, but getting fewer results than the limit. What gives?
 
-    **A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the [perDocumentLimit](/api/populate.html##limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in mind that populate() will execute a separate query for each document.
+    **A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the [perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in mind that populate() will execute a separate query for each document.
 
     <hr id="add_something" />
 

From 876577daf25e1559b9293741ca68cd394ead0669 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 May 2020 13:18:55 -0400
Subject: [PATCH 0817/2348] style: break up line

---
 docs/faq.pug | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index fddf5296f15..8f64ebf8e60 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -453,7 +453,10 @@ block content
 
     <a href="#limit-vs-perDocumentLimit">**Q**</a>. I am using `Model.find(...).populate(...)` with the `limit` option, but getting fewer results than the limit. What gives?
 
-    **A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the [perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in mind that populate() will execute a separate query for each document.
+    **A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose
+    instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the
+    [perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in
+    mind that populate() will execute a separate query for each document.
 
     <hr id="add_something" />
 

From 9037184fe95e5e26961fc3daf7632d791f82b7d0 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 6 May 2020 19:22:51 +0200
Subject: [PATCH 0818/2348] refactor(queryhelpers): make exclude depend on
 falsy values

---
 lib/queryhelpers.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 0089ca9c330..53a6f613613 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -135,7 +135,7 @@ exports.applyPaths = function applyPaths(fields, schema) {
       if (!isDefiningProjection(field)) {
         continue;
       }
-      exclude = field === 0 || field === false;
+      exclude = !field;
       break;
     }
   }

From 718f844ce4d7c1de83efc6e7cf2a1485fb54719b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 7 May 2020 10:36:21 -0400
Subject: [PATCH 0819/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 40a5bb1eb40..e23185bdb0c 100644
--- a/index.pug
+++ b/index.pug
@@ -256,6 +256,9 @@ html(lang='en')
               <a href="https://www.casinotopp.net">
                 <img class="sponsor" src="https://images.opencollective.com/casino-topp/1dd399a/logo.png" style="height: 100px">
               </a>
+              <a href="https://www.bonus.ca/">
+                <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo/256.png" style="height: 100px">
+              </a>
               <a href="https://www.bonus.net.nz/free-spins">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-new-zealand/a5becb5/logo.png" style="height: 100px">
               </a>

From cb6294e237d52bde19276461bcb8d89b4ec1d3a4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 7 May 2020 12:15:45 -0400
Subject: [PATCH 0820/2348] docs(browser): add back sample webpack config

Fix #8890
---
 test/webpack.test.js | 38 +++++++++++++++++++++++++++++++++-----
 1 file changed, 33 insertions(+), 5 deletions(-)

diff --git a/test/webpack.test.js b/test/webpack.test.js
index f486de7a3a3..31fcea670ae 100644
--- a/test/webpack.test.js
+++ b/test/webpack.test.js
@@ -16,7 +16,39 @@ describe('webpack', function() {
     const webpack = require('webpack');
     this.timeout(90000);
     // acquit:ignore:end
+    const webpackConfig = {
+      module: {
+        rules: [
+          {
+            test: /\.js$/,
+            include: [
+              /\/mongoose\//i,
+              /\/kareem\//i
+            ],
+            loader: 'babel-loader',
+            options: {
+              presets: ['es2015']
+            }
+          }
+        ]
+      },
+      node: {
+        // Replace these Node.js native modules with empty objects, Mongoose's
+        // browser library does not use them.
+        // See https://webpack.js.org/configuration/node/
+        dns: 'empty',
+        fs: 'empty',
+        module: 'empty',
+        net: 'empty',
+        tls: 'empty'
+      },
+      target: 'web',
+      mode: 'production'
+    };
+    // acquit:ignore:start
     const webpackBundle = require('../webpack.config.js');
+    const baseConfig = require('../webpack.base.config.js');
+    assert.deepEqual(webpackConfig, baseConfig);
     const webpackBundleForTest = Object.assign({}, webpackBundle, {
       output: Object.assign({}, webpackBundle.output, { path: `${__dirname}/files` })
     });
@@ -28,16 +60,12 @@ describe('webpack', function() {
       assert.ok(!bundleBuildStats.compilation.warnings.
         find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
 
-      const baseConfig = require('../webpack.base.config.js');
       const config = Object.assign({}, baseConfig, {
         entry: ['./test/files/sample.js'],
-        // acquit:ignore:start
         output: {
           path: `${__dirname}/files`
         }
-        // acquit:ignore:end
       });
-      // acquit:ignore:start
       webpack(config, utils.tick(function(error, stats) {
         assert.ifError(error);
         assert.deepEqual(stats.compilation.errors, []);
@@ -48,7 +76,7 @@ describe('webpack', function() {
 
         done();
       }));
-      // acquit:ignore:end
     }));
+    // acquit:ignore:end
   });
 });

From d98efa36b0e376e272bb6708290707ec45d242fe Mon Sep 17 00:00:00 2001
From: Jeremy Philippe <jeremy.philippe@gmail.com>
Date: Fri, 8 May 2020 11:11:28 +0200
Subject: [PATCH 0821/2348] test(update): repro #8951

---
 test/model.update.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index d5162e89d41..f26fbc67e78 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3325,6 +3325,29 @@ describe('model: updateOne: ', function() {
     });
   });
 
+  it('moves $set of immutable properties to $setOnInsert (gh-8951)', function() {
+    const Model = db.model('Test', Schema({
+      name: String,
+      age: { type: Number, default: 25, immutable: true }
+    }));
+
+    return co(function*() {
+      yield Model.bulkWrite([
+        {
+          updateOne: {
+            filter: { name: 'John' },
+            update: { name: 'John', age: 20 },
+            upsert: true,
+            setDefaultsOnInsert: true
+          }
+        }
+      ]);
+
+      const doc = yield Model.findOne().lean();
+      assert.equal(doc.age, 20);
+    });
+  });
+
   it('updates buffers with `runValidators` successfully (gh-8580)', function() {
     const Test = db.model('Test', Schema({
       data: { type: Buffer, required: true }

From 14a255594cc69c2d01e36f29642c75ed20b8da6e Mon Sep 17 00:00:00 2001
From: Jeremy Philippe <jeremy.philippe@gmail.com>
Date: Fri, 8 May 2020 11:31:40 +0200
Subject: [PATCH 0822/2348] fix(update): moveImmutableProperties() should be
 called sooner.

This is because moveImmutableProperties() modifies the update keys if
there are immutable properties, so castUpdate() would work on an invalid
set of keys.

Also, moveImmutableProperties() should only be called for upserts,
otherwise the strictness check is bypassed for regular updates (e.g.
the test for #7671 fails otherwise).

Fix #8951
---
 lib/helpers/model/castBulkWrite.js            | 6 ++++--
 lib/helpers/query/castUpdate.js               | 6 ++++--
 lib/helpers/update/moveImmutableProperties.js | 4 ++--
 lib/query.js                                  | 8 +++++++-
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index a681049dacb..c08d5886df0 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -46,7 +46,8 @@ module.exports = function castBulkWrite(model, op, options) {
         });
         op['updateOne']['update'] = castUpdate(model.schema, op['updateOne']['update'], {
           strict: strict,
-          overwrite: false
+          overwrite: false,
+          upsert: op['updateOne'].upsert
         });
 
         if (op['updateOne'].setDefaultsOnInsert) {
@@ -80,7 +81,8 @@ module.exports = function castBulkWrite(model, op, options) {
         });
         op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
           strict: strict,
-          overwrite: false
+          overwrite: false,
+          upsert: op['updateMany'].upsert
         });
         if (op['updateMany'].setDefaultsOnInsert) {
           setDefaultsOnInsert(op['updateMany']['filter'], model.schema, op['updateMany']['update'], {
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 951aa8840a2..3b83b5ad1e7 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -42,6 +42,10 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
     return obj;
   }
 
+  if (options.upsert) {
+    moveImmutableProperties(schema, obj, context);
+  }
+
   const ops = Object.keys(obj);
   let i = ops.length;
   const ret = {};
@@ -51,8 +55,6 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
 
   filter = filter || {};
 
-  moveImmutableProperties(schema, obj, context);
-
   while (i--) {
     const op = ops[i];
     // if overwrite is set, don't do any of the special $set stuff
diff --git a/lib/helpers/update/moveImmutableProperties.js b/lib/helpers/update/moveImmutableProperties.js
index d69e719ca13..8541c5bd284 100644
--- a/lib/helpers/update/moveImmutableProperties.js
+++ b/lib/helpers/update/moveImmutableProperties.js
@@ -4,8 +4,8 @@ const get = require('../get');
 
 /**
  * Given an update, move all $set on immutable properties to $setOnInsert.
- * No need to check for upserts, because there's no harm in setting
- * $setOnInsert even if `upsert` is false.
+ * This should only be called for upserts, because $setOnInsert bypasses the
+ * strictness check for immutable properties.
  */
 
 module.exports = function moveImmutableProperties(schema, update, ctx) {
diff --git a/lib/query.js b/lib/query.js
index faf2683b6a9..f55f3274f70 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4493,6 +4493,11 @@ Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
     useNestedStrict = this.options.useNestedStrict;
   }
 
+  let upsert;
+  if ('upsert' in this.options) {
+    upsert = this.options.upsert;
+  }
+
   let schema = this.schema;
   const filter = this._conditions;
   if (schema != null &&
@@ -4510,7 +4515,8 @@ Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
     overwrite: overwrite,
     strict: strict,
     omitUndefined,
-    useNestedStrict: useNestedStrict
+    useNestedStrict: useNestedStrict,
+    upsert: upsert
   }, this, this._conditions);
 };
 

From 397d812e8ff7afbc7edbcd330518f72926f8d693 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 May 2020 15:26:46 -0400
Subject: [PATCH 0823/2348] test(document): repro #8926

---
 test/document.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 22f3059603f..e6d30407eab 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8941,4 +8941,27 @@ describe('document', function() {
       then(() => Test.collection.findOne()).
       then(doc => assert.equal(doc.item.name, 'Default Name'));
   });
+
+  it('handles modifying a subpath of a nested array of documents (gh-8926)', function() {
+    const bookSchema = new Schema({ title: String });
+    const aisleSchema = new Schema({
+      shelves: [[bookSchema]]
+    });
+    const librarySchema = new Schema({ aisles: [aisleSchema] });
+
+    const Library = db.model('Test', librarySchema);
+
+    return co(function*() {
+      yield Library.create({
+        aisles: [{ shelves: [[{ title: 'Clean Code' }]] }]
+      });
+
+      const library = yield Library.findOne();
+      library.aisles[0].shelves[0][0].title = 'Refactoring';
+      yield library.save();
+
+      const foundLibrary = yield Library.findOne().lean();
+      assert.equal(foundLibrary.aisles[0].shelves[0][0].title, 'Refactoring');
+    });
+  });
 });

From 7911d9283a5f19f3c520b239262e3867332ac760 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 May 2020 15:27:02 -0400
Subject: [PATCH 0824/2348] fix(schema): mark correct path as modified when
 setting a path underneath a nested array of documents

Fix #8926
---
 lib/schema.js               |  2 ++
 lib/schema/array.js         | 10 ++++++++--
 lib/schema/documentarray.js |  9 +++++++--
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index d857b7ba636..270463d3b5d 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -746,8 +746,10 @@ Schema.prototype.path = function(path, obj) {
 
       // Skip arrays of document arrays
       if (_schemaType.$isMongooseDocumentArray) {
+        _schemaType.$embeddedSchemaType._arrayPath = arrayPath;
         _schemaType = _schemaType.$embeddedSchemaType.clone();
       } else {
+        _schemaType.caster._arrayPath = arrayPath;
         _schemaType = _schemaType.caster.clone();
       }
 
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 3986bddc559..bc828a178ab 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -300,7 +300,7 @@ SchemaArray.prototype._applySetters = function(value, scope, init, priorVal) {
  * @api private
  */
 
-SchemaArray.prototype.cast = function(value, doc, init) {
+SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
   // lazy load
   MongooseArray || (MongooseArray = require('../types').Array);
 
@@ -355,7 +355,13 @@ SchemaArray.prototype.cast = function(value, doc, init) {
           if (this.caster.instance === 'Number' && value[i] === void 0) {
             throw new MongooseError('Mongoose number arrays disallow storing undefined');
           }
-          value[i] = this.caster.cast(value[i], doc, init);
+          const opts = {};
+          if (options != null && options.arrayPath != null) {
+            opts.arrayPath = options.arrayPath + '.' + i;
+          } else if (this.caster._arrayPath != null) {
+            opts.arrayPath = this.caster._arrayPath.slice(0, -2) + '.' + i;
+          }
+          value[i] = this.caster.cast(value[i], doc, init, void 0, opts);
         }
       } catch (e) {
         // rethrow
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 3ec0e3cc27d..57e2fa441b0 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -364,6 +364,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
   let selected;
   let subdoc;
   const _opts = { transform: false, virtuals: false };
+  options = options || {};
 
   if (!Array.isArray(value)) {
     if (!init && !DocumentArrayPath.options.castNonArrays) {
@@ -374,11 +375,11 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
     if (!!doc && init) {
       doc.markModified(this.path);
     }
-    return this.cast([value], doc, init, prev);
+    return this.cast([value], doc, init, prev, options);
   }
 
   if (!(value && value.isMongooseDocumentArray) &&
-      (!options || !options.skipDocumentArrayCast)) {
+      !options.skipDocumentArrayCast) {
     value = new MongooseDocumentArray(value, this.path, doc);
   } else if (value && value.isMongooseDocumentArray) {
     // We need to create a new array, otherwise change tracking will
@@ -386,6 +387,10 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
     value = new MongooseDocumentArray(value, this.path, doc);
   }
 
+  if (options.arrayPath != null) {
+    value[arrayPathSymbol] = options.arrayPath;
+  }
+
   const len = value.length;
 
   for (let i = 0; i < len; ++i) {

From a8534e07f6eb81dd3aa643d5a64b21239488612a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 May 2020 15:34:29 -0400
Subject: [PATCH 0825/2348] chore: release 5.9.13

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 0fb455e2e62..9b2cfe1618b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.9.13 / 2020-05-08
+===================
+ * fix(schema): mark correct path as modified when setting a path underneath a nested array of documents #8926
+ * fix(query): Query#select({ field: false }) should not overwrite schema selection options #8929 #8923
+ * fix(update): handle immutable properties are ignored in bulk upserts #8952 [philippejer](https://github.com/philippejer)
+ * docs(browser): add back sample webpack config #8890
+ * docs(faq): fix broken reference in limit vs perDocumentLimit #8937
+
 5.9.12 / 2020-05-04
 ===================
  * fix(document): report cast error on array elements with array index instead of just being a cast error for the whole array #8888
diff --git a/package.json b/package.json
index 75a5711693f..becbe67f6e5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.12",
+  "version": "5.9.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 7f849c8711c119373a749158a0edffabad2be234 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 8 May 2020 23:25:21 +0200
Subject: [PATCH 0826/2348] test(document): assert Document#save accepts
 `timestamps` option

---
 test/document.test.js | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 22f3059603f..8e3bd32a9ea 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8941,4 +8941,40 @@ describe('document', function() {
       then(() => Test.collection.findOne()).
       then(doc => assert.equal(doc.item.name, 'Default Name'));
   });
+
+  it('Document#save accepts `timestamps` option (gh-8947) for update', function() {
+    return co(function*() {
+      // Arrange
+      const userSchema = new Schema({ name: String }, { timestamps: true });
+      const User = db.model('User', userSchema);
+
+      const createdUser = yield User.create({ name: 'Hafez' });
+
+      const user = yield User.findOne({ _id: createdUser._id });
+
+      // Act
+      user.name = 'John';
+      yield user.save({ timestamps: false });
+
+      // Assert
+      assert.deepEqual(createdUser.updatedAt, user.updatedAt);
+    });
+  });
+
+  it('Document#save accepts `timestamps` option (gh-8947) on inserting a new document', function() {
+    return co(function*() {
+      // Arrange
+      const userSchema = new Schema({ name: String }, { timestamps: true });
+      const User = db.model('User', userSchema);
+
+      const user = new User({ name: 'Hafez' });
+
+      // Act
+      yield user.save({ timestamps: false });
+
+      // Assert
+      assert.ok(!user.createdAt);
+      assert.ok(!user.updatedAt);
+    });
+  });
 });

From fd1a6513acadc40b778a60b7444423ffd4fd94ea Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 8 May 2020 23:31:53 +0200
Subject: [PATCH 0827/2348] docs(document): copy Model#save to Document#save

---
 lib/document.js | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 43fef6d810e..dce56008b3d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2611,28 +2611,30 @@ Document.prototype.$markValid = function(path) {
  * ####Example:
  *
  *     product.sold = Date.now();
- *     product.save(function (err, product) {
- *       if (err) ..
- *     })
- *
- * The callback will receive two parameters
+ *     product = await product.save();
  *
- * 1. `err` if an error occurred
- * 2. `product` which is the saved `product`
+ * If save is successful, the returned promise will fulfill with the document
+ * saved.
  *
- * As an extra measure of flow control, save will return a Promise.
  * ####Example:
- *     product.save().then(function(product) {
- *        ...
- *     });
+ *
+ *     const newProduct = await product.save();
+ *     newProduct === product; // true
  *
  * @param {Object} [options] options optional options
- * @param {Object} [options.safe] (DEPRECATED) overrides [schema's safe option](http://mongoosejs.com//docs/guide.html#safe)
+ * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this save operation. If not specified, defaults to the [document's associated session](api.html#document_Document-$session).
+ * @param {Object} [options.safe] (DEPRECATED) overrides [schema's safe option](http://mongoosejs.com//docs/guide.html#safe). Use the `w` option instead.
  * @param {Boolean} [options.validateBeforeSave] set to false to save without validating.
+ * @param {Number|String} [options.w] set the [write concern](https://docs.mongodb.com/manual/reference/write-concern/#w-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
+ * @param {Boolean} [options.j] set to true for MongoDB to wait until this `save()` has been [journaled before resolving the returned promise](https://docs.mongodb.com/manual/reference/write-concern/#j-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
+ * @param {Number} [options.wtimeout] sets a [timeout for the write concern](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern).
+ * @param {Boolean} [options.checkKeys=true] the MongoDB driver prevents you from saving keys that start with '$' or contain '.' by default. Set this option to `false` to skip that check. See [restrictions on field names](https://docs.mongodb.com/manual/reference/limits/#Restrictions-on-Field-Names)
+ * @param {Boolean} [options.timestamps=true] if `false` and [timestamps](./guide.html#timestamps) are enabled, skip timestamps for this `save()`.
  * @param {Function} [fn] optional callback
  * @method save
  * @memberOf Document
  * @instance
+ * @throws {DocumentNotFoundError} if this [save updates an existing document](api.html#document_Document-isNew) but the document doesn't exist in the database. For example, you will get this error if the document is [deleted between when you retrieved the document and when you saved it](documents.html#updating).
  * @return {Promise|undefined} Returns undefined if used with callback or a Promise otherwise.
  * @api public
  * @see middleware http://mongoosejs.com/docs/middleware.html

From 78c7705b87f374a69d8243359f3533afafa4e98e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 May 2020 12:02:26 -0400
Subject: [PATCH 0828/2348] test(update): repro #8922

---
 test/model.update.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index f26fbc67e78..64dd4fb5a4e 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3431,5 +3431,26 @@ describe('model: updateOne: ', function() {
         assert.ok(updated.updatedAt.getTime() > updatedAt.getTime());
       });
     });
+
+    it('use child schema strict on single nested updates if useNestedStrict not set (gh-8922)', function() {
+      const ContactSchema = Schema({ email: String }, {
+        _id: false,
+        strict: false
+      });
+    
+      const StoreSchema = Schema({ contact: ContactSchema });
+      const Store = db.model('Test', StoreSchema);
+
+      return co(function*() {
+        yield Store.updateOne({}, {
+          contact: {
+            email: '234@example.com', notInSchema: '234'
+          }
+        }, { upsert: true });
+        const updatedStore = yield Store.collection.findOne();
+        assert.strictEqual(updatedStore.contact.email, '234@example.com');
+        assert.strictEqual(updatedStore.contact.notInSchema, '234');
+      });
+    });
   });
 });
\ No newline at end of file

From 1fcab18115b254570d3a39ec5226693317f229d6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 May 2020 12:02:36 -0400
Subject: [PATCH 0829/2348] fix(update): use child schema strict on single
 nested updates if useNestedStrict not set

Fix #8922

For backwards compat because 5.9.8 ended up breaking this behavior
---
 lib/helpers/query/castUpdate.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 3b83b5ad1e7..327d9d2f862 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -227,7 +227,7 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
             // Special case to make sure `strict` bubbles down correctly to
             // single nested re: gh-8735
             let _strict = strict;
-            if (useNestedStrict && schematype.schema.options.hasOwnProperty('strict')) {
+            if (useNestedStrict !== false && schematype.schema.options.hasOwnProperty('strict')) {
               _strict = schematype.schema.options.strict;
             } else if (useNestedStrict === false) {
               _strict = schema.options.strict;

From 53833984c2e8efca2816ea9369d52b3ae9a1987f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 May 2020 12:03:39 -0400
Subject: [PATCH 0830/2348] style: fix lint

---
 test/model.update.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 64dd4fb5a4e..1b6b677cfea 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3437,7 +3437,7 @@ describe('model: updateOne: ', function() {
         _id: false,
         strict: false
       });
-    
+
       const StoreSchema = Schema({ contact: ContactSchema });
       const Store = db.model('Test', StoreSchema);
 

From 1345781ecc5903581b6d8cfb9c8b3789746bc044 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 May 2020 12:27:21 -0400
Subject: [PATCH 0831/2348] test(query): repro #8881

---
 test/query.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index 96474a65d1f..09bb5ea8323 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3613,4 +3613,20 @@ describe('Query', function() {
       });
     });
   });
+
+  it('casts filter according to discriminator schema if in filter (gh-8881)', function() {
+    const userSchema = new Schema({ name: String }, { discriminatorKey: 'kind' });
+    const User = db.model('User', userSchema);
+
+    return co(function*() {
+      const UserWithAge = User.discriminator('UserWithAge', new Schema({ age: Number }));
+      yield UserWithAge.create({ name: 'Hafez', age: 25 });
+
+      // should cast `age` to number
+      const user = yield User.findOne({ kind: 'UserWithAge', age: '25' });
+
+      assert.equal(user.name, 'Hafez');
+      assert.equal(user.age, 25);
+    });
+  });
 });

From f6ac2abe77580db0a3fd4e22d2f858fbc6b32ce0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 May 2020 12:27:34 -0400
Subject: [PATCH 0832/2348] fix(query): cast filter according to discriminator
 schema if discriminator key in filter

Fix #8881
---
 lib/query.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/query.js b/lib/query.js
index f55f3274f70..de1686e703c 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4720,6 +4720,12 @@ Query.prototype.cast = function(model, obj) {
 
   model = model || this.model;
 
+  const discriminatorKey = model.schema.options.discriminatorKey;
+  if (obj != null &&
+      obj.hasOwnProperty(discriminatorKey)) {
+    model = getDiscriminatorByValue(model, obj[discriminatorKey]) || model;
+  }
+
   try {
     return cast(model.schema, obj, {
       upsert: this.options && this.options.upsert,

From 3b1bee66b94d61a65cf49222b6574cf370c1a8d4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 10 May 2020 08:56:01 +0200
Subject: [PATCH 0833/2348] refactor: sort schema reserved keys

---
 lib/schema.js | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index d857b7ba636..4991ccfa2ad 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -535,28 +535,28 @@ Schema.prototype.add = function add(obj, prefix) {
  * using `new Schema()` with one of these property names, Mongoose will throw
  * an error.
  *
- * - prototype
- * - emit
- * - on
- * - once
- * - listeners
- * - removeListener
+ * - _posts
+ * - _pres
  * - collection
  * - db
+ * - emit
  * - errors
+ * - get
  * - init
  * - isModified
  * - isNew
- * - get
+ * - listeners
  * - modelName
+ * - on
+ * - once
+ * - populated
+ * - prototype
+ * - remove
+ * - removeListener
  * - save
  * - schema
  * - toObject
  * - validate
- * - remove
- * - populated
- * - _pres
- * - _posts
  *
  * _NOTE:_ Use of these terms as method names is permitted, but play at your own risk, as they may be existing mongoose document methods you are stomping on.
  *
@@ -571,23 +571,23 @@ const reserved = Schema.reserved;
 reserved['prototype'] =
 // EventEmitter
 reserved.emit =
-reserved.on =
 reserved.listeners =
+reserved.on =
 reserved.removeListener =
 // document properties and functions
 reserved.collection =
 reserved.db =
 reserved.errors =
+reserved.get =
 reserved.init =
 reserved.isModified =
 reserved.isNew =
-reserved.get =
+reserved.populated =
+reserved.remove =
 reserved.save =
 reserved.schema =
 reserved.toObject =
-reserved.validate =
-reserved.remove =
-reserved.populated = 1;
+reserved.validate = 1;
 
 /*!
  * Document keys to print warnings for

From d7b8ff258b25b7a8b68828966d07ab4b28bebe17 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 06:20:20 +0200
Subject: [PATCH 0834/2348] test(model): fix flaky text for model.populate

---
 test/model.populate.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index b2afcb57b06..e1c000ab75e 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9294,7 +9294,7 @@ describe('model: populate:', function() {
           { title: 'test3', user: new mongoose.Types.ObjectId() }
         ]);
 
-        const posts = yield Post.find().populate({ path: 'user', options: { clone: true } }).lean();
+        const posts = yield Post.find().populate({ path: 'user', options: { clone: true } }).sort('title').lean();
 
         posts[0].user.name = 'val2';
         assert.equal(posts[1].user.name, 'val');
@@ -9356,4 +9356,4 @@ describe('model: populate:', function() {
       });
     });
   });
-});
\ No newline at end of file
+});

From b29e6e276b0467922c6916c85108fe36569f3322 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 06:38:16 +0200
Subject: [PATCH 0835/2348] refactor(eachAsync): step-down `iterate` and
 handleNextResult`

---
 lib/helpers/cursor/eachAsync.js | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index cd99280fc93..951ae697661 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -24,18 +24,11 @@ module.exports = function eachAsync(next, fn, options, callback) {
   const parallel = options.parallel || 1;
   const enqueue = asyncQueue();
 
-  const handleNextResult = function(doc, callback) {
-    const promise = fn(doc);
-    if (promise && typeof promise.then === 'function') {
-      promise.then(
-        function() { callback(null); },
-        function(error) { callback(error || new Error('`eachAsync()` promise rejected without error')); });
-    } else {
-      callback(null);
-    }
-  };
+  return promiseOrCallback(callback, cb => {
+    iterate(cb);
+  });
 
-  const iterate = function(finalCallback) {
+  function iterate(finalCallback) {
     let drained = false;
     let handleResultsInProgress = 0;
 
@@ -86,11 +79,18 @@ module.exports = function eachAsync(next, fn, options, callback) {
         });
       });
     }
-  };
+  }
 
-  return promiseOrCallback(callback, cb => {
-    iterate(cb);
-  });
+  function handleNextResult(doc, callback) {
+    const promise = fn(doc);
+    if (promise && typeof promise.then === 'function') {
+      promise.then(
+        function() { callback(null); },
+        function(error) { callback(error || new Error('`eachAsync()` promise rejected without error')); });
+    } else {
+      callback(null);
+    }
+  }
 };
 
 // `next()` can only execute one at a time, so make sure we always execute

From bc7dcb94ba376ae5b6ab8f3413e94374f7c382d9 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 08:04:15 +0200
Subject: [PATCH 0836/2348] test(eachAsync): repro: #8972

---
 test/query.cursor.test.js | 45 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index dcd322679cc..b184a2bd3de 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -561,6 +561,51 @@ describe('QueryCursor', function() {
       assert.equal(closeEventTriggeredCount, 1);
       done();
     }, 20);
+  });
+
+  it('passes document index as the second argument for query cursor (gh-8972)', function() {
+    return co(function *() {
+      const User = db.model('User', Schema({ order: Number }));
+
+      yield User.create([{ order: 1 }, { order: 2 }, { order: 3 }]);
+
+
+      const docsWithIndexes = [];
 
+      yield User.find().sort('order').cursor().eachAsync((doc, i) => {
+        docsWithIndexes.push({ order: doc.order, i: i });
+      });
+
+      const expected = [
+        { order: 1, i: 0 },
+        { order: 2, i: 1 },
+        { order: 3, i: 2 }
+      ];
+
+      assert.deepEqual(docsWithIndexes, expected);
+    });
+  });
+
+  it('passes document index as the second argument for aggregation cursor (gh-8972)', function() {
+    return co(function *() {
+      const User = db.model('User', Schema({ order: Number }));
+
+      yield User.create([{ order: 1 }, { order: 2 }, { order: 3 }]);
+
+
+      const docsWithIndexes = [];
+
+      yield User.aggregate([{ $sort: { order: 1 } }]).cursor().exec().eachAsync((doc, i) => {
+        docsWithIndexes.push({ order: doc.order, i: i });
+      });
+
+      const expected = [
+        { order: 1, i: 0 },
+        { order: 2, i: 1 },
+        { order: 3, i: 2 }
+      ];
+
+      assert.deepEqual(docsWithIndexes, expected);
+    });
   });
 });

From 55c096d4008a5107a7733f09509bcc7589a493cd Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 08:23:19 +0200
Subject: [PATCH 0837/2348] fix(eachAsync): add index as a second parameter to
 callback

---
 lib/aggregate.js                |  2 +-
 lib/cursor/QueryCursor.js       | 11 +++++++++++
 lib/helpers/cursor/eachAsync.js |  7 ++++---
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index 5bfd82215f4..cc31f09b98d 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -820,7 +820,7 @@ Aggregate.prototype.option = function(value) {
  * ####Example:
  *
  *     var cursor = Model.aggregate(..).cursor({ batchSize: 1000 }).exec();
- *     cursor.eachAsync(function(error, doc) {
+ *     cursor.eachAsync(function(doc, i) {
  *       // use doc
  *     });
  *
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 4fd31c66dbc..a77f5bb472a 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -199,6 +199,17 @@ QueryCursor.prototype.next = function(callback) {
  * will wait for the promise to resolve before iterating on to the next one.
  * Returns a promise that resolves when done.
  *
+ * ####Example
+ *
+ *     // Iterate over documents asynchronously
+ *     Thing.
+ *       find({ name: /^hello/ }).
+ *       cursor().
+ *       eachAsync(async function (doc, i) {
+ *         doc.foo = doc.bar + i;
+ *         await doc.save();
+ *       })
+ *
  * @param {Function} fn
  * @param {Object} [options]
  * @param {Number} [options.parallel] the number of promises to execute in parallel. Defaults to 1.
diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 951ae697661..4afff032fe8 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -31,6 +31,7 @@ module.exports = function eachAsync(next, fn, options, callback) {
   function iterate(finalCallback) {
     let drained = false;
     let handleResultsInProgress = 0;
+    let currentDocumentIndex = 0;
 
     let error = null;
     for (let i = 0; i < parallel; ++i) {
@@ -65,7 +66,7 @@ module.exports = function eachAsync(next, fn, options, callback) {
         // make sure we know that we still have a result to handle re: #8422
         process.nextTick(() => done());
 
-        handleNextResult(doc, function(err) {
+        handleNextResult(doc, currentDocumentIndex++, function(err) {
           --handleResultsInProgress;
           if (err != null) {
             error = err;
@@ -81,8 +82,8 @@ module.exports = function eachAsync(next, fn, options, callback) {
     }
   }
 
-  function handleNextResult(doc, callback) {
-    const promise = fn(doc);
+  function handleNextResult(doc, i, callback) {
+    const promise = fn(doc, i);
     if (promise && typeof promise.then === 'function') {
       promise.then(
         function() { callback(null); },

From 252875278de90857a46b024207d28a2e44bc8268 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 11:49:05 +0200
Subject: [PATCH 0838/2348] test(model): repro #8953

---
 test/model.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 6bd5082acb9..f8412c40e40 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6691,4 +6691,13 @@ describe('Model', function() {
     });
   });
 
+  it('cast errors have `kind` field (gh-8953)', function() {
+    return co(function*() {
+      const User = db.model('User', {});
+      const err = yield User.findOne({ _id: 'invalid' }).then(() => null, err => err);
+
+      assert.deepEqual(err.kind, 'ObjectId');
+    });
+  });
+
 });

From 0e719db490a16c812a35a9b22f90b3f5391ac1ef Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 11:53:05 +0200
Subject: [PATCH 0839/2348] fix(castError): add `kind` to cast errors thrown by
 query execution

---
 lib/error/cast.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 1e9ffaf9dab..671931718e8 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -68,7 +68,7 @@ CastError.prototype.init = function init(type, value, path, reason, schemaType)
 CastError.prototype.copy = function copy(other) {
   this.messageFormat = other.messageFormat;
   this.stringValue = other.stringValue;
-  this.kind = other.type;
+  this.kind = other.kind;
   this.value = other.value;
   this.path = other.path;
   this.reason = other.reason;

From 04cef93202210ecbdf30b1edce1a13d47e786f9a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 13:14:04 +0200
Subject: [PATCH 0840/2348] refactor(getModelsMapForPopulate): step-down and
 use for of instead of for let i

---
 lib/helpers/populate/getModelsMapForPopulate.js | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 79902c11302..deb9d345773 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -17,8 +17,6 @@ const schemaMixedSymbol = require('../../schema/symbols').schemaMixedSymbol;
 
 module.exports = function getModelsMapForPopulate(model, docs, options) {
   let i;
-  let doc;
-  const len = docs.length;
   const available = {};
   const map = [];
   const modelNameFromQuery = options.model && options.model.modelName || options.model;
@@ -31,16 +29,14 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
   let modelForFindSchema;
 
   const originalModel = options.model;
-  let isVirtual = false;
   const modelSchema = model.schema;
+  let isVirtual = false;
 
   let allSchemaTypes = getSchemaTypes(modelSchema, null, options.path);
   allSchemaTypes = Array.isArray(allSchemaTypes) ? allSchemaTypes : [allSchemaTypes].filter(v => v != null);
   const _firstWithRefPath = allSchemaTypes.find(schematype => get(schematype, 'options.refPath', null) != null);
 
-  for (i = 0; i < len; i++) {
-    doc = docs[i];
-
+  for (const doc of docs) {
     schema = getSchemaTypes(modelSchema, doc, options.path);
     const isUnderneathDocArray = schema && schema.$isUnderneathDocArray;
     if (isUnderneathDocArray && get(options, 'options.sort') != null) {
@@ -317,6 +313,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     }
   }
 
+  return map;
+
   function _getModelNames(doc, schema) {
     let modelNames;
     let discriminatorKey;
@@ -431,8 +429,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
     return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath };
   }
-
-  return map;
 };
 
 /*!

From 3133039dca4670164dfa92926568bec272055fcd Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 13:24:22 +0200
Subject: [PATCH 0841/2348] test: repro #8924

---
 test/model.populate.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index b2afcb57b06..cd79b7bfe16 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9355,5 +9355,27 @@ describe('model: populate:', function() {
         assert.equal(result.events[1].productId.name, 'GTX 1050 Ti');
       });
     });
+
+    it('can populate virtuals defined on child discriminators (gh-8924)', function() {
+      return co(function*() {
+        const User = db.model('User', {});
+        const Post = db.model('Post', { name: String });
+
+        const userWithPostSchema = new Schema({ postId: Schema.ObjectId });
+
+        userWithPostSchema.virtual('post', { ref: 'Post', localField: 'postId', foreignField: '_id', justOne: true });
+
+        const UserWithPost = User.discriminator('UserWithPost', userWithPostSchema);
+
+        const post = yield Post.create({ name: 'Clean Code' });
+
+        yield UserWithPost.create({ postId: post._id });
+
+        const user = yield User.findOne().populate({ path: 'post' });
+
+
+        assert.equal(user.post.name, 'Clean Code');
+      });
+    });
   });
 });
\ No newline at end of file

From 0a14ab84b9b3c11cbad8174b876e92a4899e7144 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 11 May 2020 13:40:32 +0200
Subject: [PATCH 0842/2348] fix(populate): populate virtuals defined on child
 discriminators

---
 lib/helpers/populate/getModelsMapForPopulate.js | 8 ++++++--
 lib/helpers/populate/getVirtual.js              | 8 ++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index deb9d345773..d6b51c397d3 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -17,6 +17,8 @@ const schemaMixedSymbol = require('../../schema/symbols').schemaMixedSymbol;
 
 module.exports = function getModelsMapForPopulate(model, docs, options) {
   let i;
+  let doc;
+  const len = docs.length;
   const available = {};
   const map = [];
   const modelNameFromQuery = options.model && options.model.modelName || options.model;
@@ -29,14 +31,16 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
   let modelForFindSchema;
 
   const originalModel = options.model;
-  const modelSchema = model.schema;
   let isVirtual = false;
+  const modelSchema = model.schema;
 
   let allSchemaTypes = getSchemaTypes(modelSchema, null, options.path);
   allSchemaTypes = Array.isArray(allSchemaTypes) ? allSchemaTypes : [allSchemaTypes].filter(v => v != null);
   const _firstWithRefPath = allSchemaTypes.find(schematype => get(schematype, 'options.refPath', null) != null);
 
-  for (const doc of docs) {
+  for (i = 0; i < len; i++) {
+    doc = docs[i];
+
     schema = getSchemaTypes(modelSchema, doc, options.path);
     const isUnderneathDocArray = schema && schema.$isUnderneathDocArray;
     if (isUnderneathDocArray && get(options, 'options.sort') != null) {
diff --git a/lib/helpers/populate/getVirtual.js b/lib/helpers/populate/getVirtual.js
index 3f4a129c91e..fc1641d4087 100644
--- a/lib/helpers/populate/getVirtual.js
+++ b/lib/helpers/populate/getVirtual.js
@@ -10,6 +10,7 @@ function getVirtual(schema, name) {
   if (schema.virtuals[name]) {
     return { virtual: schema.virtuals[name], path: void 0 };
   }
+
   const parts = name.split('.');
   let cur = '';
   let nestedSchemaPath = '';
@@ -59,6 +60,13 @@ function getVirtual(schema, name) {
       continue;
     }
 
+    if (schema.discriminators) {
+      for (const discriminatorKey of Object.keys(schema.discriminators)) {
+        const virtualFromDiscriminator = getVirtual(schema.discriminators[discriminatorKey], name);
+        if (virtualFromDiscriminator) return virtualFromDiscriminator;
+      }
+    }
+
     return null;
   }
 }

From 1383a4812d4a7b14654b9acc9931de0b3c6703f9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 11 May 2020 15:14:14 -0400
Subject: [PATCH 0843/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index e23185bdb0c..1a329a34019 100644
--- a/index.pug
+++ b/index.pug
@@ -340,6 +340,9 @@ html(lang='en')
               <a href="https://casinohex.se/online-casinon/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-se/795919b/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://casinohex.co.za/online-casinos/">
+                <img class="sponsor" src="https://images.opencollective.com/casinohex-co-za/470843d/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 537154e3430b82ec42d46e1acc93948763a4ea9e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 12 May 2020 12:18:30 +0200
Subject: [PATCH 0844/2348] test: repro #8982

---
 test/query.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index 09bb5ea8323..bc0b27ea519 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3629,4 +3629,21 @@ describe('Query', function() {
       assert.equal(user.age, 25);
     });
   });
+
+  it('casts update object according to child discriminator schema when `discriminatorKey` is present (gh-8982)', function() {
+    const userSchema = new Schema({ }, { discriminatorKey: 'kind' });
+    const Person = db.model('Person', userSchema);
+
+    return co(function*() {
+      const Worker = Person.discriminator('Worker', new Schema({ locations: [String] }));
+      const worker = yield Worker.create({ locations: ['US'] });
+
+      // should cast `update` according to `Worker` schema
+      yield Person.updateOne({ _id: worker._id, kind: 'Worker' }, { $push: { locations: 'UK' } });
+
+      const person = yield Person.findOne({ _id: worker._id });
+
+      assert.deepEqual(person.locations, ['US', 'UK']);
+    });
+  });
 });

From c02ce2cbc2b4a9cf120bfd30762f7f71bd065479 Mon Sep 17 00:00:00 2001
From: osher <osher.filter@gmail.com>
Date: Tue, 12 May 2020 16:42:24 +0300
Subject: [PATCH 0845/2348] fix(errors): user defines its own r/o err.toJSON

When user code defines it's own Error.prototype.toJSON, which is defined as a read-only property - the fixed line crashes.
It happens specificly because of the old-school `Object.create(prototype)` thing.
---
 lib/error/validation.js                   | 12 ++++++++----
 test/errors.validation.test.js            | 15 +++++++++++++++
 test/isolated/project-has-error.toJSON.js |  9 +++++++++
 3 files changed, 32 insertions(+), 4 deletions(-)
 create mode 100644 test/isolated/project-has-error.toJSON.js

diff --git a/lib/error/validation.js b/lib/error/validation.js
index 6959ed5dc65..a0e5d72f54a 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -72,10 +72,14 @@ if (util.inspect.custom) {
 /*!
  * Helper for JSON.stringify
  */
-
-ValidationError.prototype.toJSON = function() {
-  return Object.assign({}, this, { message: this.message });
-};
+Object.defineProperty(ValidationError.prototype, 'toJSON', {
+  enumerable: false,
+  writabe: false,
+  configurable: true,
+  value: function() {
+    return Object.assign({}, this, { message: this.message });
+  }
+});
 
 /*!
  * add message
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index ffc834b8da5..14d5942360e 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -232,4 +232,19 @@ describe('ValidationError', function() {
 
     assert.equal(err.message, 'Validation failed');
   });
+
+  describe('when user code defines a r/o Error#toJSON', function() {
+    it('shoud not fail', function() {
+      const err = [];
+      const child = require('child_process')
+        .fork('./test/isolated/project-has-error.toJSON.js', { silent: true });
+
+      child.stderr.on('data', function(buf) { err.push(buf); });
+      child.on('exit', function(code) {
+        const stderr = err.join('');
+        assert.equal(stderr, '');
+        assert.equal(code, 0);
+      });
+    });
+  });
 });
diff --git a/test/isolated/project-has-error.toJSON.js b/test/isolated/project-has-error.toJSON.js
new file mode 100644
index 00000000000..74e5cfb4145
--- /dev/null
+++ b/test/isolated/project-has-error.toJSON.js
@@ -0,0 +1,9 @@
+'use strict';
+Object.defineProperty(Error.prototype, 'toJSON', {
+  enumerable: false,
+  configurable: false,
+  writable: false,
+  value: () => ({ from: 'Error' })
+});
+
+require('../../');

From 0dd361aa93aa15671280f24e2a87b925497b7773 Mon Sep 17 00:00:00 2001
From: Andrew Smith <andrew.smith5569@gmail.com>
Date: Tue, 12 May 2020 11:18:22 -0400
Subject: [PATCH 0846/2348] doc: add immutable type to Schema Types

---
 docs/schematypes.pug | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 2d086b9663b..7c7ac9edcdb 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -231,6 +231,7 @@ block content
     * `get`: function, defines a custom getter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
     * `set`: function, defines a custom setter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
     * `alias`: string, mongoose >= 4.10.0 only. Defines a [virtual](./guide.html#virtuals) with the given name that gets/sets this path.
+    * `immutable`: boolean, defines path as immutable. Mongoose prevents you from changing immutable paths unless the parent document has `isNew: true`.
 
     ```javascript
     var numberSchema = new Schema({

From d05dc13c55cdb8f5df61df0e3a53dce363f82cfa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 12 May 2020 18:00:33 -0400
Subject: [PATCH 0847/2348] chore: fix typo

---
 lib/error/validation.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/error/validation.js b/lib/error/validation.js
index a0e5d72f54a..ced82fc6957 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -74,7 +74,7 @@ if (util.inspect.custom) {
  */
 Object.defineProperty(ValidationError.prototype, 'toJSON', {
   enumerable: false,
-  writabe: false,
+  writable: false,
   configurable: true,
   value: function() {
     return Object.assign({}, this, { message: this.message });

From bf9315d4962ac3cb161a2377b874d0cf0966cc2f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 May 2020 13:49:23 +0200
Subject: [PATCH 0848/2348] test: repro #8982 bulkwrite casting

---
 test/model.test.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 6bd5082acb9..60b54cfd588 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5636,6 +5636,39 @@ describe('Model', function() {
           assert.equal(userAfterUpdate.name, 'Hafez', 'Document data is not wiped if no update object is provided.');
         });
       });
+
+      it('casts according to child discriminator if `discriminatorKey` is present (gh-8982)', function() {
+        return co(function*() {
+          const Person = db.model('Person', { name: String });
+          Person.discriminator('Worker', new Schema({ age: Number }));
+
+
+          const [person1, person2, person3, person4, person5] = yield Person.create([
+            { __t: 'Worker', name: 'Hafez1', age: '5' },
+            { __t: 'Worker', name: 'Hafez2', age: '10' },
+            { __t: 'Worker', name: 'Hafez3', age: '15' },
+            { __t: 'Worker', name: 'Hafez4', age: '20' },
+            { __t: 'Worker', name: 'Hafez5', age: '25' }
+          ]);
+
+          yield Person.bulkWrite([
+            { updateOne: { filter: { __t: 'Worker', _id: person1._id, age: '5' }, update: { age: '6' } } },
+            { updateMany: { filter: { __t: 'Worker', _id: person2._id, age: '10' }, update: { age: '11' } } },
+            { replaceOne: { filter: { __t: 'Worker', _id: person3._id, age: '15' }, replacement: { name: 'Hafez3', age: '16' } } },
+            { deleteOne: { filter: { __t: 'Worker', _id: person4._id, age: '20' } } },
+            { deleteMany: { filter: { __t: 'Worker', _id: person5._id, age: '25' } } },
+            { insertOne: { document: { __t: 'Worker', name: 'Hafez6', age: '30' } } }
+          ]);
+
+          const people = yield Person.find().sort('name');
+
+          assert.equal(people.length, 4);
+          assert.equal(people[0].age, 6);
+          assert.equal(people[1].age, 11);
+          assert.equal(people[2].age, 16);
+          assert.equal(people[3].age, 30);
+        });
+      });
     });
 
     it('insertMany with Decimal (gh-5190)', function(done) {

From 968175632dc17f053b40a4055fbd14540b3f8431 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 May 2020 13:57:31 +0200
Subject: [PATCH 0849/2348] fix(model): cast bulkwrite according to
 discriminator schema if discriminator key is present

---
 .../discriminator/getDiscriminatorByValue.js  |  4 +-
 lib/helpers/model/castBulkWrite.js            | 41 +++++++++++++++++--
 test/model.test.js                            | 12 +++---
 3 files changed, 45 insertions(+), 12 deletions(-)

diff --git a/lib/helpers/discriminator/getDiscriminatorByValue.js b/lib/helpers/discriminator/getDiscriminatorByValue.js
index 87b3ad9940a..a107a910492 100644
--- a/lib/helpers/discriminator/getDiscriminatorByValue.js
+++ b/lib/helpers/discriminator/getDiscriminatorByValue.js
@@ -16,8 +16,8 @@ module.exports = function getDiscriminatorByValue(model, value) {
     const it = model.discriminators[name];
     if (
       it.schema &&
-     it.schema.discriminatorMapping &&
-     it.schema.discriminatorMapping.value == value
+      it.schema.discriminatorMapping &&
+      it.schema.discriminatorMapping.value == value
     ) {
       discriminator = it;
       break;
diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index c08d5886df0..8ba0d86b9c8 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -1,5 +1,6 @@
 'use strict';
 
+const getDiscriminatorByValue = require('../../helpers/discriminator/getDiscriminatorByValue');
 const applyTimestampsToChildren = require('../update/applyTimestampsToChildren');
 const applyTimestampsToUpdate = require('../update/applyTimestampsToUpdate');
 const cast = require('../../cast');
@@ -11,13 +12,13 @@ const setDefaultsOnInsert = require('../setDefaultsOnInsert');
  * validating the individual op.
  */
 
-module.exports = function castBulkWrite(model, op, options) {
-  const now = model.base.now();
-  const schema = model.schema;
-  const strict = options.strict != null ? options.strict : model.schema.options.strict;
+module.exports = function castBulkWrite(originalModel, op, options) {
+  const now = originalModel.base.now();
 
   if (op['insertOne']) {
     return (callback) => {
+      const model = decideModelByObject(originalModel, op['insertOne']['document']);
+
       const doc = new model(op['insertOne']['document']);
       if (model.schema.options.timestamps != null) {
         doc.initializeTimestamps();
@@ -36,6 +37,10 @@ module.exports = function castBulkWrite(model, op, options) {
   } else if (op['updateOne']) {
     return (callback) => {
       try {
+        const model = decideModelByObject(originalModel, op['updateOne']['filter']);
+        const schema = model.schema;
+        const strict = options.strict != null ? options.strict : model.schema.options.strict;
+
         if (!op['updateOne']['filter']) throw new Error('Must provide a filter object.');
         if (!op['updateOne']['update']) throw new Error('Must provide an update object.');
 
@@ -74,6 +79,10 @@ module.exports = function castBulkWrite(model, op, options) {
         if (!op['updateMany']['filter']) throw new Error('Must provide a filter object.');
         if (!op['updateMany']['update']) throw new Error('Must provide an update object.');
 
+        const model = decideModelByObject(originalModel, op['updateMany']['filter']);
+        const schema = model.schema;
+        const strict = options.strict != null ? options.strict : model.schema.options.strict;
+
         _addDiscriminatorToObject(schema, op['updateMany']['filter']);
         op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter'], {
           strict: strict,
@@ -104,6 +113,10 @@ module.exports = function castBulkWrite(model, op, options) {
     };
   } else if (op['replaceOne']) {
     return (callback) => {
+      const model = decideModelByObject(originalModel, op['replaceOne']['filter']);
+      const schema = model.schema;
+      const strict = options.strict != null ? options.strict : model.schema.options.strict;
+
       _addDiscriminatorToObject(schema, op['replaceOne']['filter']);
       try {
         op['replaceOne']['filter'] = cast(model.schema, op['replaceOne']['filter'], {
@@ -133,7 +146,11 @@ module.exports = function castBulkWrite(model, op, options) {
     };
   } else if (op['deleteOne']) {
     return (callback) => {
+      const model = decideModelByObject(originalModel, op['deleteOne']['filter']);
+      const schema = model.schema;
+
       _addDiscriminatorToObject(schema, op['deleteOne']['filter']);
+
       try {
         op['deleteOne']['filter'] = cast(model.schema,
           op['deleteOne']['filter']);
@@ -145,7 +162,11 @@ module.exports = function castBulkWrite(model, op, options) {
     };
   } else if (op['deleteMany']) {
     return (callback) => {
+      const model = decideModelByObject(originalModel, op['deleteMany']['filter']);
+      const schema = model.schema;
+
       _addDiscriminatorToObject(schema, op['deleteMany']['filter']);
+
       try {
         op['deleteMany']['filter'] = cast(model.schema,
           op['deleteMany']['filter']);
@@ -169,4 +190,16 @@ function _addDiscriminatorToObject(schema, obj) {
   if (schema.discriminatorMapping && !schema.discriminatorMapping.isRoot) {
     obj[schema.discriminatorMapping.key] = schema.discriminatorMapping.value;
   }
+}
+
+/*!
+ * gets discriminator model if discriminator key is present in object
+ */
+
+function decideModelByObject(model, object) {
+  const discriminatorKey = model.schema.options.discriminatorKey;
+  if (object != null && object.hasOwnProperty(discriminatorKey)) {
+    model = getDiscriminatorByValue(model, object[discriminatorKey]) || model;
+  }
+  return model;
 }
\ No newline at end of file
diff --git a/test/model.test.js b/test/model.test.js
index 60b54cfd588..d293f518c1e 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5643,7 +5643,7 @@ describe('Model', function() {
           Person.discriminator('Worker', new Schema({ age: Number }));
 
 
-          const [person1, person2, person3, person4, person5] = yield Person.create([
+          yield Person.create([
             { __t: 'Worker', name: 'Hafez1', age: '5' },
             { __t: 'Worker', name: 'Hafez2', age: '10' },
             { __t: 'Worker', name: 'Hafez3', age: '15' },
@@ -5652,11 +5652,11 @@ describe('Model', function() {
           ]);
 
           yield Person.bulkWrite([
-            { updateOne: { filter: { __t: 'Worker', _id: person1._id, age: '5' }, update: { age: '6' } } },
-            { updateMany: { filter: { __t: 'Worker', _id: person2._id, age: '10' }, update: { age: '11' } } },
-            { replaceOne: { filter: { __t: 'Worker', _id: person3._id, age: '15' }, replacement: { name: 'Hafez3', age: '16' } } },
-            { deleteOne: { filter: { __t: 'Worker', _id: person4._id, age: '20' } } },
-            { deleteMany: { filter: { __t: 'Worker', _id: person5._id, age: '25' } } },
+            { updateOne: { filter: { __t: 'Worker', age: '5' }, update: { age: '6' } } },
+            { updateMany: { filter: { __t: 'Worker', age: '10' }, update: { age: '11' } } },
+            { replaceOne: { filter: { __t: 'Worker', age: '15' }, replacement: { name: 'Hafez3', age: '16' } } },
+            { deleteOne: { filter: { __t: 'Worker', age: '20' } } },
+            { deleteMany: { filter: { __t: 'Worker', age: '25' } } },
             { insertOne: { document: { __t: 'Worker', name: 'Hafez6', age: '30' } } }
           ]);
 

From 87752e33bbf3c04b22e05a499273ba10ed2f1703 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 May 2020 14:08:57 +0200
Subject: [PATCH 0850/2348] validate operation before attempting to get model
 on `updateOne`

---
 lib/helpers/model/castBulkWrite.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 8ba0d86b9c8..c45ee5d483b 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -37,13 +37,13 @@ module.exports = function castBulkWrite(originalModel, op, options) {
   } else if (op['updateOne']) {
     return (callback) => {
       try {
+        if (!op['updateOne']['filter']) throw new Error('Must provide a filter object.');
+        if (!op['updateOne']['update']) throw new Error('Must provide an update object.');
+
         const model = decideModelByObject(originalModel, op['updateOne']['filter']);
         const schema = model.schema;
         const strict = options.strict != null ? options.strict : model.schema.options.strict;
 
-        if (!op['updateOne']['filter']) throw new Error('Must provide a filter object.');
-        if (!op['updateOne']['update']) throw new Error('Must provide an update object.');
-
         _addDiscriminatorToObject(schema, op['updateOne']['filter']);
         op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter'], {
           strict: strict,

From 5663a9762d290c945e83e33bd8d27fdca178a292 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 May 2020 14:43:30 +0200
Subject: [PATCH 0851/2348] test: repro #8984

---
 test/model.discriminator.test.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 4bf886e5f5b..55c3c6a6f0d 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1577,4 +1577,11 @@ describe('model', function() {
       assert.ok(user.postId);
     })
   });
+
+  it('accepts a POJO as a schema for discriminators (gh-8984)', function () {
+    const User = db.model('User',{});
+    const SuperUser = User.discriminator('SuperUser',{})
+
+    assert.ok(SuperUser.schema)
+  })
 });

From 33b8ccc2a64c72a7ab31a5c863967ff9198c32b9 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 13 May 2020 14:44:15 +0200
Subject: [PATCH 0852/2348] fix(model): allow POJOs as schemas for
 model.discriminator(...)

---
 lib/model.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index cc9a7851232..bdaf9af1959 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1112,6 +1112,10 @@ Model.discriminator = function(name, schema, value) {
 
   _checkContext(this, 'discriminator');
 
+  if (utils.isObject(schema) && !schema.instanceOfSchema) {
+    schema = new Schema(schema);
+  }
+
   schema = discriminator(this, name, schema, value, true);
   if (this.db.models[name]) {
     throw new OverwriteModelError(name);

From dbdc417f6186c2ebc6c654db75ab549ff8236bc9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 May 2020 18:24:26 -0400
Subject: [PATCH 0853/2348] chore: release 5.9.14

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9b2cfe1618b..eed6cc667b1 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.9.14 / 2020-05-13
+===================
+ * fix(cursor): add index as second parameter to eachAsync callback #8972 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(query): cast filter according to discriminator schema if discriminator key in filter #8881
+ * fix(model): fix throwing error when populating virtual path defined on child discriminator #8924 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(errors): handle case when user has make `Error.prototype.toJSON` read only #8986 [osher](https://github.com/osher)
+ * fix(model): add `kind` to cast errors thrown by query execution #8953 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(update): use child schema strict on single nested updates if useNestedStrict not set #8922
+ * docs(model): improve `save()` docs #8956 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: add immutable type to Schema Types #8987 [Andrew5569](https://github.com/Andrew5569)
+ * docs: sort schema reserved keys in documentation #8966 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.9.13 / 2020-05-08
 ===================
  * fix(schema): mark correct path as modified when setting a path underneath a nested array of documents #8926
diff --git a/package.json b/package.json
index becbe67f6e5..62aab6f6b91 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.13",
+  "version": "5.9.14",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b75b51c1538a19e04f54922f868b6049e6027e88 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 07:38:23 +0200
Subject: [PATCH 0854/2348] test: improve assertion for #8984

---
 test/model.discriminator.test.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 55c3c6a6f0d..5832900b063 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1578,10 +1578,10 @@ describe('model', function() {
     })
   });
 
-  it('accepts a POJO as a schema for discriminators (gh-8984)', function () {
-    const User = db.model('User',{});
-    const SuperUser = User.discriminator('SuperUser',{})
+  it('accepts a POJO as a schema for discriminators (gh-8984)', function() {
+    const User = db.model('User', {});
+    const SuperUser = User.discriminator('SuperUser', { ability: String });
 
-    assert.ok(SuperUser.schema)
-  })
+    assert.ok(SuperUser.schema.path('ability'));
+  });
 });

From 6fe7baae0b6a66b2dadc6a5a2e95d4103810a005 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 07:43:11 +0200
Subject: [PATCH 0855/2348] lint: fix model.discriminator.test linting

---
 .eslintignore                    |   1 -
 test/model.discriminator.test.js | 450 +++++++++++++++----------------
 2 files changed, 225 insertions(+), 226 deletions(-)

diff --git a/.eslintignore b/.eslintignore
index e3fa9dcd9a9..506abbb9a9a 100644
--- a/.eslintignore
+++ b/.eslintignore
@@ -1,7 +1,6 @@
 docs/
 bin/
 test/triage/
-test/model.discriminator.test.js
 tools/
 test/es-next/
 test/files/
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 4bf886e5f5b..ae336eb6da8 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -19,10 +19,10 @@ const Schema = mongoose.Schema;
  * Setup
  */
 const PersonSchema = new Schema({
-  name: {first: String, last: String},
+  name: { first: String, last: String },
   gender: String
-}, {collection: 'model-discriminator-' + random()});
-PersonSchema.index({name: 1});
+}, { collection: 'model-discriminator-' + random() });
+PersonSchema.index({ name: 1 });
 PersonSchema.methods.getFullName = function() {
   return this.name.first + ' ' + this.name.last;
 };
@@ -36,18 +36,18 @@ PersonSchema.virtual('name.full').get(function() {
   return this.name.first + ' ' + this.name.last;
 });
 PersonSchema.virtual('name.full').set(function(name) {
-  var split = name.split(' ');
+  const split = name.split(' ');
   this.name.first = split[0];
   this.name.last = split[1];
 });
 PersonSchema.path('gender').validate(function(value) {
   return /[A-Z]/.test(value);
 }, 'Invalid name');
-PersonSchema.set('toObject', {getters: true, virtuals: true});
-PersonSchema.set('toJSON', {getters: true, virtuals: true});
+PersonSchema.set('toObject', { getters: true, virtuals: true });
+PersonSchema.set('toJSON', { getters: true, virtuals: true });
 
-var EmployeeSchema = new Schema({department: String});
-EmployeeSchema.index({department: 1});
+const EmployeeSchema = new Schema({ department: String });
+EmployeeSchema.index({ department: 1 });
 EmployeeSchema.methods.getDepartment = function() {
   return this.department;
 };
@@ -56,12 +56,12 @@ EmployeeSchema.statics.findByDepartment = function() {
 EmployeeSchema.path('department').validate(function(value) {
   return /[a-zA-Z]/.test(value);
 }, 'Invalid name');
-var employeeSchemaPreSaveFn = function(next) {
+const employeeSchemaPreSaveFn = function(next) {
   next();
 };
 EmployeeSchema.pre('save', employeeSchemaPreSaveFn);
-EmployeeSchema.set('toObject', {getters: true, virtuals: false});
-EmployeeSchema.set('toJSON', {getters: false, virtuals: true});
+EmployeeSchema.set('toObject', { getters: true, virtuals: false });
+EmployeeSchema.set('toJSON', { getters: false, virtuals: true });
 
 describe('model', function() {
   let db;
@@ -79,7 +79,7 @@ describe('model', function() {
   afterEach(() => require('./util').stopRemainingOps(db));
 
   describe('discriminator()', function() {
-    var Person, Employee;
+    let Person, Employee;
 
     before(function() {
       db = start();
@@ -88,14 +88,14 @@ describe('model', function() {
     });
 
     it('model defaults without discriminator', function(done) {
-      var Model = db.model('Test1', new Schema());
+      const Model = db.model('Test1', new Schema());
       assert.equal(Model.discriminators, undefined);
       done();
     });
 
     it('is instance of root', function(done) {
       assert.equal(Employee.baseModelName, 'Test');
-      var employee = new Employee();
+      const employee = new Employee();
       assert.ok(employee instanceof Person);
       assert.ok(employee instanceof Employee);
       assert.strictEqual(employee.__proto__.constructor, Employee);
@@ -115,18 +115,18 @@ describe('model', function() {
 
       util.inherits(BossBaseSchema, Schema);
 
-      var PersonSchema = new BossBaseSchema();
-      var BossSchema = new BossBaseSchema({department: String});
+      const PersonSchema = new BossBaseSchema();
+      const BossSchema = new BossBaseSchema({ department: String });
       BossSchema.methods.myName = function() {
         return this.name;
       };
       BossSchema.statics.currentPresident = function() {
         return 'obama';
       };
-      var Person = db.model('Person', PersonSchema);
-      var Boss = Person.discriminator('Boss', BossSchema);
+      const Person = db.model('Person', PersonSchema);
+      const Boss = Person.discriminator('Boss', BossSchema);
 
-      var boss = new Boss({name: 'Bernenke'});
+      const boss = new Boss({ name: 'Bernenke' });
       assert.equal(boss.myName(), 'Bernenke');
       assert.equal(boss.notInstanceMethod, undefined);
       assert.equal(Boss.currentPresident(), 'obama');
@@ -135,17 +135,17 @@ describe('model', function() {
     });
 
     it('sets schema root discriminator mapping', function(done) {
-      assert.deepEqual(Person.schema.discriminatorMapping, {key: '__t', value: null, isRoot: true});
+      assert.deepEqual(Person.schema.discriminatorMapping, { key: '__t', value: null, isRoot: true });
       done();
     });
 
     it('sets schema discriminator type mapping', function(done) {
-      assert.deepEqual(Employee.schema.discriminatorMapping, {key: '__t', value: 'Employee', isRoot: false});
+      assert.deepEqual(Employee.schema.discriminatorMapping, { key: '__t', value: 'Employee', isRoot: false });
       done();
     });
 
     it('adds discriminatorKey to schema with default as name', function(done) {
-      var type = Employee.schema.paths.__t;
+      const type = Employee.schema.paths.__t;
       assert.equal(type.options.type, String);
       assert.equal(type.options.default, 'Employee');
       done();
@@ -154,8 +154,8 @@ describe('model', function() {
     it('adds discriminator to Model.discriminators object', function(done) {
       assert.equal(Object.keys(Person.discriminators).length, 1);
       assert.equal(Person.discriminators['Employee'], Employee);
-      var newName = 'model-discriminator-' + random();
-      var NewDiscriminatorType = Person.discriminator(newName, new Schema());
+      const newName = 'model-discriminator-' + random();
+      const NewDiscriminatorType = Person.discriminator(newName, new Schema());
       assert.equal(Object.keys(Person.discriminators).length, 2);
       assert.equal(Person.discriminators[newName], NewDiscriminatorType);
       done();
@@ -163,59 +163,59 @@ describe('model', function() {
 
     it('throws error on invalid schema', function(done) {
       assert.throws(
-          function() {
-            Person.discriminator('Foo');
-          },
-          /You must pass a valid discriminator Schema/
+        function() {
+          Person.discriminator('Foo');
+        },
+        /You must pass a valid discriminator Schema/
       );
       done();
     });
 
     it('throws error when attempting to nest discriminators', function(done) {
       assert.throws(
-          function() {
-            Employee.discriminator('model-discriminator-foo', new Schema());
-          },
-          /Discriminator "model-discriminator-foo" can only be a discriminator of the root model/
+        function() {
+          Employee.discriminator('model-discriminator-foo', new Schema());
+        },
+        /Discriminator "model-discriminator-foo" can only be a discriminator of the root model/
       );
       done();
     });
 
     it('throws error when discriminator has mapped discriminator key in schema', function(done) {
       assert.throws(
-          function() {
-            Person.discriminator('model-discriminator-foo', new Schema({__t: String}));
-          },
-          /Discriminator "model-discriminator-foo" cannot have field with name "__t"/
+        function() {
+          Person.discriminator('model-discriminator-foo', new Schema({ __t: String }));
+        },
+        /Discriminator "model-discriminator-foo" cannot have field with name "__t"/
       );
       done();
     });
 
     it('throws error when discriminator has mapped discriminator key in schema with discriminatorKey option set', function(done) {
       assert.throws(
-          function() {
-            var Foo = db.model('Test1', new Schema({}, {discriminatorKey: '_type'}));
-            Foo.discriminator('Bar', new Schema({_type: String}));
-          },
-          /Discriminator "Bar" cannot have field with name "_type"/
+        function() {
+          const Foo = db.model('Test1', new Schema({}, { discriminatorKey: '_type' }));
+          Foo.discriminator('Bar', new Schema({ _type: String }));
+        },
+        /Discriminator "Bar" cannot have field with name "_type"/
       );
       done();
     });
 
     it('throws error when discriminator with taken name is added', function(done) {
-      var Foo = db.model('Test1', new Schema({}));
+      const Foo = db.model('Test1', new Schema({}));
       Foo.discriminator('Token', new Schema());
       assert.throws(
-          function() {
-            Foo.discriminator('Token', new Schema());
-          },
-          /Discriminator with name "Token" already exists/
+        function() {
+          Foo.discriminator('Token', new Schema());
+        },
+        /Discriminator with name "Token" already exists/
       );
       done();
     });
 
     it('throws error if model name is taken (gh-4148)', function(done) {
-      var Foo = db.model('Test1', new Schema({}));
+      const Foo = db.model('Test1', new Schema({}));
       db.model('Test', new Schema({}));
       assert.throws(
         function() {
@@ -226,7 +226,7 @@ describe('model', function() {
     });
 
     it('works with nested schemas (gh-2821)', function(done) {
-      var MinionSchema = function() {
+      const MinionSchema = function() {
         mongoose.Schema.apply(this, arguments);
 
         this.add({
@@ -235,7 +235,7 @@ describe('model', function() {
       };
       util.inherits(MinionSchema, mongoose.Schema);
 
-      var BaseSchema = function() {
+      const BaseSchema = function() {
         mongoose.Schema.apply(this, arguments);
 
         this.add({
@@ -246,13 +246,13 @@ describe('model', function() {
       };
       util.inherits(BaseSchema, mongoose.Schema);
 
-      var PersonSchema = new BaseSchema();
-      var BossSchema = new BaseSchema({
+      const PersonSchema = new BaseSchema();
+      const BossSchema = new BaseSchema({
         department: String
       }, { id: false });
 
       // Should not throw
-      var Person = db.model('Test1', PersonSchema);
+      const Person = db.model('Test1', PersonSchema);
       Person.discriminator('Boss', BossSchema);
       done();
     });
@@ -260,18 +260,18 @@ describe('model', function() {
     describe('options', function() {
       it('allows toObject to be overridden', function(done) {
         assert.notDeepEqual(Employee.schema.get('toObject'), Person.schema.get('toObject'));
-        assert.deepEqual(Employee.schema.get('toObject'), {getters: true, virtuals: false});
+        assert.deepEqual(Employee.schema.get('toObject'), { getters: true, virtuals: false });
         done();
       });
 
       it('allows toJSON to be overridden', function(done) {
         assert.notDeepEqual(Employee.schema.get('toJSON'), Person.schema.get('toJSON'));
-        assert.deepEqual(Employee.schema.get('toJSON'), {getters: false, virtuals: true});
+        assert.deepEqual(Employee.schema.get('toJSON'), { getters: false, virtuals: true });
         done();
       });
 
       it('is not customizable', function(done) {
-        var CustomizedSchema = new Schema({}, {capped: true});
+        const CustomizedSchema = new Schema({}, { capped: true });
 
         assert.throws(function() {
           Person.discriminator('model-discriminator-custom', CustomizedSchema);
@@ -296,10 +296,10 @@ describe('model', function() {
       });
 
       it('does not inherit and override fields that exist', function(done) {
-        var FemaleSchema = new Schema({gender: {type: String, default: 'F'}}),
+        const FemaleSchema = new Schema({ gender: { type: String, default: 'F' } }),
             Female = Person.discriminator('model-discriminator-female', FemaleSchema);
 
-        var gender = Female.schema.paths.gender;
+        const gender = Female.schema.paths.gender;
 
         assert.notStrictEqual(gender, Person.schema.paths.gender);
         assert.equal(gender.instance, 'String');
@@ -308,7 +308,7 @@ describe('model', function() {
       });
 
       it('inherits methods', function(done) {
-        var employee = new Employee();
+        const employee = new Employee();
         assert.strictEqual(employee.getFullName, PersonSchema.methods.getFullName);
         assert.strictEqual(employee.getDepartment, EmployeeSchema.methods.getDepartment);
         assert.equal((new Person).getDepartment, undefined);
@@ -323,20 +323,20 @@ describe('model', function() {
       });
 
       it('inherits virtual (g.s)etters', function(done) {
-        var employee = new Employee();
+        const employee = new Employee();
         employee.name.full = 'John Doe';
         assert.equal(employee.name.full, 'John Doe');
         done();
       });
 
       it('does not inherit indexes', function(done) {
-        assert.deepEqual(Person.schema.indexes(), [[{name: 1}, {background: true}]]);
-        assert.deepEqual(Employee.schema.indexes(), [[{department: 1}, {background: true}]]);
+        assert.deepEqual(Person.schema.indexes(), [[{ name: 1 }, { background: true }]]);
+        assert.deepEqual(Employee.schema.indexes(), [[{ department: 1 }, { background: true }]]);
         done();
       });
 
       it('gets options overridden by root options except toJSON and toObject', function(done) {
-        var personOptions = clone(Person.schema.options),
+        const personOptions = clone(Person.schema.options),
             employeeOptions = clone(Employee.schema.options);
 
         delete personOptions.toJSON;
@@ -349,7 +349,7 @@ describe('model', function() {
       });
 
       it('does not allow setting discriminator key (gh-2041)', function(done) {
-        var doc = new Employee({ __t: 'fake' });
+        const doc = new Employee({ __t: 'fake' });
         assert.equal(doc.__t, 'Employee');
         doc.save(function(error) {
           assert.ok(error);
@@ -387,13 +387,13 @@ describe('model', function() {
         return new D({ text: 'test' }).validate().
           then(() => {
             assert.equal(called, 1);
-          })
+          });
       });
 
       it('with typeKey (gh-4339)', function(done) {
-        var options = { typeKey: '$type', discriminatorKey: '_t' };
-        var schema = new Schema({ test: { $type: String } }, options);
-        var Model = db.model('Test', schema);
+        const options = { typeKey: '$type', discriminatorKey: '_t' };
+        const schema = new Schema({ test: { $type: String } }, options);
+        const Model = db.model('Test', schema);
         Model.discriminator('D', new Schema({
           test2: String
         }, { typeKey: '$type' }));
@@ -409,18 +409,18 @@ describe('model', function() {
         });
 
         it('works (gh-4965)', function(done) {
-          var schema = new m.Schema({ test: String });
-          var called = 0;
+          const schema = new m.Schema({ test: String });
+          let called = 0;
           m.plugin(function() {
             ++called;
           });
-          var Model = m.model('Test', schema);
-          var childSchema = new m.Schema({
+          const Model = m.model('Test', schema);
+          const childSchema = new m.Schema({
             test2: String
           });
           Model.discriminator('D', childSchema);
           assert.equal(called, 2);
-  
+
           done();
         });
 
@@ -429,21 +429,21 @@ describe('model', function() {
             schema.options.versionKey = false;
             schema.options.minimize = false;
           });
-          
+
           const schema = new m.Schema({
-            type: {type: String},
-            something: {type: String}
+            type: { type: String },
+            something: { type: String }
           }, {
             discriminatorKey: 'type'
           });
           const Model = m.model('Test', schema);
-          
+
           const subSchema = new m.Schema({
-            somethingElse: {type: String}
+            somethingElse: { type: String }
           });
 
           // Should not throw
-          const SubModel = Model.discriminator('TestSub', subSchema);
+          Model.discriminator('TestSub', subSchema);
 
           return Promise.resolve();
         });
@@ -461,7 +461,7 @@ describe('model', function() {
           items: {
             type: [abstractSchema],
             default: defaultValue
-          },
+          }
         });
 
         schema.path('items').discriminator('concrete', concreteSchema);
@@ -481,7 +481,7 @@ describe('model', function() {
         const batchSchema = new Schema({ events: [eventSchema] });
         const docArray = batchSchema.path('events');
 
-        const Clicked = docArray.discriminator('Clicked', new Schema({
+        docArray.discriminator('Clicked', new Schema({
           element: {
             type: String,
             required: true
@@ -526,10 +526,10 @@ describe('model', function() {
       it('embedded discriminator with numeric type (gh-7808)', function() {
         const typesSchema = Schema({
           type: { type: Number }
-        }, { discriminatorKey:'type',_id:false });
+        }, { discriminatorKey: 'type', _id: false });
 
         const mainSchema = Schema({
-          types:[typesSchema]
+          types: [typesSchema]
         });
 
         mainSchema.path('types').discriminator(1,
@@ -551,12 +551,12 @@ describe('model', function() {
       });
 
       it('supports clone() (gh-4983)', function(done) {
-        var childSchema = new Schema({
+        const childSchema = new Schema({
           name: String
         });
-        var childCalls = 0;
-        var childValidateCalls = 0;
-        var preValidate = function preValidate(next) {
+        let childCalls = 0;
+        let childValidateCalls = 0;
+        const preValidate = function preValidate(next) {
           ++childValidateCalls;
           next();
         };
@@ -566,29 +566,29 @@ describe('model', function() {
           next();
         });
 
-        var personSchema = new Schema({
+        const personSchema = new Schema({
           name: String
         }, { discriminatorKey: 'kind' });
 
-        var parentSchema = new Schema({
+        const parentSchema = new Schema({
           children: [childSchema],
           heir: childSchema
         });
-        var parentCalls = 0;
+        let parentCalls = 0;
         parentSchema.pre('save', function(next) {
           ++parentCalls;
           next();
         });
 
-        var Person = db.model('Person', personSchema);
-        var Parent = Person.discriminator('Parent', parentSchema.clone());
+        const Person = db.model('Person', personSchema);
+        const Parent = Person.discriminator('Parent', parentSchema.clone());
 
-        var obj = {
+        const obj = {
           name: 'Ned Stark',
           heir: { name: 'Robb Stark' },
           children: [{ name: 'Jon Snow' }]
         };
-        var doc = new Parent(obj);
+        const doc = new Parent(obj);
 
         doc.save(function(error, doc) {
           assert.ifError(error);
@@ -604,37 +604,37 @@ describe('model', function() {
       });
 
       it('clone() allows reusing schemas (gh-5098)', function(done) {
-        var personSchema = new Schema({
+        const personSchema = new Schema({
           name: String
         }, { discriminatorKey: 'kind' });
 
-        var parentSchema = new Schema({
+        const parentSchema = new Schema({
           child: String
         });
 
-        var Person = db.model('Person', personSchema);
-        var Parent = Person.discriminator('Parent', parentSchema.clone());
+        const Person = db.model('Person', personSchema);
+        Person.discriminator('Parent', parentSchema.clone());
         // Should not throw
-        var Parent2 = Person.discriminator('Parent2', parentSchema.clone());
+        Person.discriminator('Parent2', parentSchema.clone());
         done();
       });
 
       it('clone() allows reusing with different models (gh-5721)', function(done) {
-        var schema = new mongoose.Schema({
+        const schema = new mongoose.Schema({
           name: String
         });
 
-        var schemaExt = new mongoose.Schema({
+        const schemaExt = new mongoose.Schema({
           nameExt: String
         });
 
-        var ModelA = db.model('Test1', schema);
+        const ModelA = db.model('Test1', schema);
         ModelA.discriminator('D1', schemaExt);
 
         ModelA.findOneAndUpdate({}, { $set: { name: 'test' } }, function(error) {
           assert.ifError(error);
 
-          var ModelB = db.model('Test2', schema.clone());
+          const ModelB = db.model('Test2', schema.clone());
           ModelB.discriminator('D2', schemaExt.clone());
 
           done();
@@ -652,7 +652,7 @@ describe('model', function() {
           });
 
           const Setting = db.model('Test', settingSchema);
-          const DefaultAdvisor = Setting.discriminator('DefaultAdvisor',
+          Setting.discriminator('DefaultAdvisor',
             defaultAdvisorSchema);
 
           let threw = false;
@@ -672,22 +672,22 @@ describe('model', function() {
       });
 
       it('copies query hooks (gh-5147)', function(done) {
-        var options = { discriminatorKey: 'kind' };
+        const options = { discriminatorKey: 'kind' };
 
-        var eventSchema = new mongoose.Schema({ time: Date }, options);
-        var eventSchemaCalls = 0;
+        const eventSchema = new mongoose.Schema({ time: Date }, options);
+        let eventSchemaCalls = 0;
         eventSchema.pre('findOneAndUpdate', function() {
           ++eventSchemaCalls;
         });
 
-        var Event = db.model('Test', eventSchema);
+        const Event = db.model('Test', eventSchema);
 
-        var clickedEventSchema = new mongoose.Schema({ url: String }, options);
-        var clickedEventSchemaCalls = 0;
+        const clickedEventSchema = new mongoose.Schema({ url: String }, options);
+        let clickedEventSchemaCalls = 0;
         clickedEventSchema.pre('findOneAndUpdate', function() {
           ++clickedEventSchemaCalls;
         });
-        var ClickedLinkEvent = Event.discriminator('ClickedLink', clickedEventSchema);
+        const ClickedLinkEvent = Event.discriminator('ClickedLink', clickedEventSchema);
 
         ClickedLinkEvent.findOneAndUpdate({}, { time: new Date() }, {}).
           exec(function(error) {
@@ -699,26 +699,26 @@ describe('model', function() {
       });
 
       it('reusing schema for discriminators (gh-5684)', function(done) {
-        var ParentSchema = new Schema({});
-        var ChildSchema = new Schema({ name: String });
+        const ParentSchema = new Schema({});
+        const ChildSchema = new Schema({ name: String });
 
-        var FirstContainerSchema = new Schema({
+        const FirstContainerSchema = new Schema({
           stuff: [ParentSchema]
         });
 
         FirstContainerSchema.path('stuff').discriminator('Child', ChildSchema);
 
-        var SecondContainerSchema = new Schema({
+        const SecondContainerSchema = new Schema({
           things: [ParentSchema]
         });
 
         SecondContainerSchema.path('things').discriminator('Child', ChildSchema);
 
-        var M1 = db.model('Test1', FirstContainerSchema);
-        var M2 = db.model('Test2', SecondContainerSchema);
+        const M1 = db.model('Test1', FirstContainerSchema);
+        const M2 = db.model('Test2', SecondContainerSchema);
 
-        var doc1 = new M1({ stuff: [{ __t: 'Child', name: 'test' }] });
-        var doc2 = new M2({ things: [{ __t: 'Child', name: 'test' }] });
+        const doc1 = new M1({ stuff: [{ __t: 'Child', name: 'test' }] });
+        const doc2 = new M2({ things: [{ __t: 'Child', name: 'test' }] });
 
         assert.equal(doc1.stuff.length, 1);
         assert.equal(doc1.stuff[0].name, 'test');
@@ -731,7 +731,7 @@ describe('model', function() {
       it('overwrites nested paths in parent schema (gh-6076)', function(done) {
         const schema = mongoose.Schema({
           account: {
-            type: Object,
+            type: Object
           }
         });
 
@@ -751,9 +751,9 @@ describe('model', function() {
 
         const d1 = new Disc({
           account: {
-            user: 'AAAAAAAAAAAAAAAAAAAAAAAA',
+            user: 'AAAAAAAAAAAAAAAAAAAAAAAA'
           },
-          info: 'AAAAAAAAAAAAAAAAAAAAAAAA',
+          info: 'AAAAAAAAAAAAAAAAAAAAAAAA'
         });
 
         // Should not throw
@@ -763,20 +763,20 @@ describe('model', function() {
       });
 
       it('nested discriminator key with projecting in parent (gh-5775)', function(done) {
-        var itemSchema = new Schema({
+        const itemSchema = new Schema({
           type: { type: String },
           active: { type: Boolean, default: true }
         }, { discriminatorKey: 'type' });
 
-        var collectionSchema = new Schema({
+        const collectionSchema = new Schema({
           items: [itemSchema]
         });
 
-        var s = new Schema({ count: Number });
+        const s = new Schema({ count: Number });
         collectionSchema.path('items').discriminator('type1', s);
 
-        var MyModel = db.model('Test', collectionSchema);
-        var doc = {
+        const MyModel = db.model('Test', collectionSchema);
+        const doc = {
           items: [{ type: 'type1', active: false, count: 3 }]
         };
         MyModel.create(doc, function(error) {
@@ -793,15 +793,15 @@ describe('model', function() {
       });
 
       it('with $meta projection (gh-5859)', function() {
-        var eventSchema = new Schema({ eventField: String }, { id: false });
-        var Event = db.model('Test', eventSchema);
+        const eventSchema = new Schema({ eventField: String }, { id: false });
+        const Event = db.model('Test', eventSchema);
 
-        var trackSchema = new Schema({ trackField: String });
-        var Track = Event.discriminator('Track', trackSchema);
+        const trackSchema = new Schema({ trackField: String });
+        const Track = Event.discriminator('Track', trackSchema);
 
-        var trackedItem = new Track({
+        const trackedItem = new Track({
           trackField: 'trackField',
-          eventField: 'eventField',
+          eventField: 'eventField'
         });
 
         return trackedItem.save().
@@ -823,28 +823,28 @@ describe('model', function() {
       });
 
       it('embedded discriminators with $push (gh-5009)', function(done) {
-        var eventSchema = new Schema({ message: String },
+        const eventSchema = new Schema({ message: String },
           { discriminatorKey: 'kind', _id: false });
-        var batchSchema = new Schema({ events: [eventSchema] });
-        var docArray = batchSchema.path('events');
+        const batchSchema = new Schema({ events: [eventSchema] });
+        const docArray = batchSchema.path('events');
 
-        var Clicked = docArray.discriminator('Clicked', new Schema({
+        docArray.discriminator('Clicked', new Schema({
           element: {
             type: String,
             required: true
           }
         }, { _id: false }));
 
-        var Purchased = docArray.discriminator('Purchased', new Schema({
+        docArray.discriminator('Purchased', new Schema({
           product: {
             type: String,
             required: true
           }
         }, { _id: false }));
 
-        var Batch = db.model('Test', batchSchema);
+        const Batch = db.model('Test', batchSchema);
 
-        var batch = {
+        const batch = {
           events: [
             { kind: 'Clicked', element: '#hero' }
           ]
@@ -874,28 +874,28 @@ describe('model', function() {
       });
 
       it('embedded discriminators with $push + $each (gh-5070)', function(done) {
-        var eventSchema = new Schema({ message: String },
+        const eventSchema = new Schema({ message: String },
           { discriminatorKey: 'kind', _id: false });
-        var batchSchema = new Schema({ events: [eventSchema] });
-        var docArray = batchSchema.path('events');
+        const batchSchema = new Schema({ events: [eventSchema] });
+        const docArray = batchSchema.path('events');
 
-        var Clicked = docArray.discriminator('Clicked', new Schema({
+        docArray.discriminator('Clicked', new Schema({
           element: {
             type: String,
             required: true
           }
         }, { _id: false }));
 
-        var Purchased = docArray.discriminator('Purchased', new Schema({
+        docArray.discriminator('Purchased', new Schema({
           product: {
             type: String,
             required: true
           }
         }, { _id: false }));
 
-        var Batch = db.model('Test1', batchSchema);
+        const Batch = db.model('Test1', batchSchema);
 
-        var batch = {
+        const batch = {
           events: [
             { kind: 'Clicked', element: '#hero' }
           ]
@@ -925,28 +925,28 @@ describe('model', function() {
       });
 
       it('embedded discriminators with $set (gh-5130)', function(done) {
-        var eventSchema = new Schema({ message: String },
+        const eventSchema = new Schema({ message: String },
           { discriminatorKey: 'kind' });
-        var batchSchema = new Schema({ events: [eventSchema] });
-        var docArray = batchSchema.path('events');
+        const batchSchema = new Schema({ events: [eventSchema] });
+        const docArray = batchSchema.path('events');
 
-        var Clicked = docArray.discriminator('Clicked', new Schema({
+        docArray.discriminator('Clicked', new Schema({
           element: {
             type: String,
             required: true
           }
         }));
 
-        var Purchased = docArray.discriminator('Purchased', new Schema({
+        docArray.discriminator('Purchased', new Schema({
           product: {
             type: String,
             required: true
           }
         }));
 
-        var Batch = db.model('Test1', batchSchema);
+        const Batch = db.model('Test1', batchSchema);
 
-        var batch = {
+        const batch = {
           events: [
             { kind: 'Clicked', element: '#hero' }
           ]
@@ -957,7 +957,7 @@ describe('model', function() {
             assert.equal(doc.events.length, 1);
             return Batch.updateOne({ _id: doc._id, 'events._id': doc.events[0]._id }, {
               $set: {
-                'events.$':  {
+                'events.$': {
                   message: 'updated',
                   kind: 'Clicked',
                   element: '#hero2'
@@ -971,18 +971,18 @@ describe('model', function() {
           then(function(doc) {
             assert.equal(doc.events.length, 1);
             assert.equal(doc.events[0].message, 'updated');
-            assert.equal(doc.events[0].element, '#hero2');    // <-- test failed
-            assert.equal(doc.events[0].kind, 'Clicked');      // <-- test failed
+            assert.equal(doc.events[0].element, '#hero2'); // <-- test failed
+            assert.equal(doc.events[0].kind, 'Clicked'); // <-- test failed
             done();
           }).
           catch(done);
       });
 
       it('embedded in document arrays (gh-2723)', function(done) {
-        var eventSchema = new Schema({ message: String },
+        const eventSchema = new Schema({ message: String },
           { discriminatorKey: 'kind', _id: false });
 
-        var batchSchema = new Schema({ events: [eventSchema] });
+        const batchSchema = new Schema({ events: [eventSchema] });
         batchSchema.path('events').discriminator('Clicked', new Schema({
           element: String
         }, { _id: false }));
@@ -990,8 +990,8 @@ describe('model', function() {
           product: String
         }, { _id: false }));
 
-        var MyModel = db.model('Test1', batchSchema);
-        var doc = {
+        const MyModel = db.model('Test1', batchSchema);
+        const doc = {
           events: [
             { kind: 'Clicked', element: 'Test' },
             { kind: 'Purchased', product: 'Test2' }
@@ -1002,7 +1002,7 @@ describe('model', function() {
             assert.equal(doc.events.length, 2);
             assert.equal(doc.events[0].element, 'Test');
             assert.equal(doc.events[1].product, 'Test2');
-            var obj = doc.toObject({ virtuals: false });
+            const obj = doc.toObject({ virtuals: false });
             delete obj._id;
             assert.deepEqual(obj, {
               __v: 0,
@@ -1033,10 +1033,10 @@ describe('model', function() {
     });
 
     it('embedded with single nested subdocs (gh-5244)', function(done) {
-      var eventSchema = new Schema({ message: String },
+      const eventSchema = new Schema({ message: String },
         { discriminatorKey: 'kind', _id: false });
 
-      var trackSchema = new Schema({ event: eventSchema });
+      const trackSchema = new Schema({ event: eventSchema });
       trackSchema.path('event').discriminator('Clicked', new Schema({
         element: String
       }, { _id: false }));
@@ -1044,14 +1044,14 @@ describe('model', function() {
         product: String
       }, { _id: false }));
 
-      var MyModel = db.model('Test1', trackSchema);
-      var doc1 = {
+      const MyModel = db.model('Test1', trackSchema);
+      const doc1 = {
         event: {
           kind: 'Clicked',
           element: 'Amazon Link'
         }
       };
-      var doc2 = {
+      const doc2 = {
         event: {
           kind: 'Purchased',
           product: 'Professional AngularJS'
@@ -1059,8 +1059,8 @@ describe('model', function() {
       };
       MyModel.create([doc1, doc2]).
         then(function(docs) {
-          var doc1 = docs[0];
-          var doc2 = docs[1];
+          const doc1 = docs[0];
+          const doc2 = docs[1];
 
           assert.equal(doc1.event.kind, 'Clicked');
           assert.equal(doc1.event.element, 'Amazon Link');
@@ -1078,7 +1078,7 @@ describe('model', function() {
       const eventSchema = new Schema({ message: String },
         { discriminatorKey: 'kind', _id: false });
 
-        const trackSchema = new Schema({ event: eventSchema });
+      const trackSchema = new Schema({ event: eventSchema });
       trackSchema.path('event').discriminator('Clicked', new Schema({
         element: String
       }, { _id: false }), 'click');
@@ -1124,9 +1124,9 @@ describe('model', function() {
       const docArray = batchSchema.path('events');
 
       const clickedSchema = new Schema({
-        element: {type: String, required: true}
+        element: { type: String, required: true }
       }, { _id: false });
-      const Clicked = docArray.discriminator('Clicked', clickedSchema);
+      docArray.discriminator('Clicked', clickedSchema);
 
       const M = db.model('Test1', batchSchema);
 
@@ -1145,7 +1145,7 @@ describe('model', function() {
       const arr = batchSchema.path('events');
 
       const clickedSchema = new Schema({
-        element: {type: String, required: true}
+        element: { type: String, required: true }
       }, { _id: false });
 
       let threw = false;
@@ -1170,19 +1170,19 @@ describe('model', function() {
       const conA = mongoose.createConnection(start.uri);
 
       const schemaExt = new Schema({ nameExt: String });
-      
+
       const modelA = conA.model('Test', schema);
       modelA.discriminator('AExt', schemaExt);
-      
+
       const conB = mongoose.createConnection(start.uri);
-      
+
       const modelB = conB.model('Test1', schema);
       modelB.discriminator('AExt', schemaExt);
-      
+
     });
 
-    describe('embedded discriminators + hooks (gh-5706)', function(){
-      var counters = {
+    describe('embedded discriminators + hooks (gh-5706)', function() {
+      const counters = {
         eventPreSave: 0,
         eventPostSave: 0,
         purchasePreSave: 0,
@@ -1190,9 +1190,9 @@ describe('model', function() {
         eventPreValidate: 0,
         eventPostValidate: 0,
         purchasePreValidate: 0,
-        purchasePostValidate: 0,
+        purchasePostValidate: 0
       };
-      var eventSchema = new Schema(
+      const eventSchema = new Schema(
         { message: String },
         { discriminatorKey: 'kind', _id: false }
       );
@@ -1201,7 +1201,7 @@ describe('model', function() {
         next();
       });
 
-      eventSchema.post('validate', function(doc) {
+      eventSchema.post('validate', function() {
         counters.eventPostValidate++;
       });
 
@@ -1210,12 +1210,12 @@ describe('model', function() {
         next();
       });
 
-      eventSchema.post('save', function(doc) {
+      eventSchema.post('save', function() {
         counters.eventPostSave++;
       });
 
-      var purchasedSchema = new Schema({
-        product: String,
+      const purchasedSchema = new Schema({
+        product: String
       }, { _id: false });
 
       purchasedSchema.pre('validate', function(next) {
@@ -1223,7 +1223,7 @@ describe('model', function() {
         next();
       });
 
-      purchasedSchema.post('validate', function(doc) {
+      purchasedSchema.post('validate', function() {
         counters.purchasePostValidate++;
       });
 
@@ -1232,7 +1232,7 @@ describe('model', function() {
         next();
       });
 
-      purchasedSchema.post('save', function(doc) {
+      purchasedSchema.post('save', function() {
         counters.purchasePostSave++;
       });
 
@@ -1242,25 +1242,25 @@ describe('model', function() {
         });
       });
 
-      it('should call the hooks on the embedded document defined by both the parent and discriminated schemas', function(done){
-        var trackSchema = new Schema({
-          event: eventSchema,
+      it('should call the hooks on the embedded document defined by both the parent and discriminated schemas', function(done) {
+        const trackSchema = new Schema({
+          event: eventSchema
         });
 
-        var embeddedEventSchema = trackSchema.path('event');
+        const embeddedEventSchema = trackSchema.path('event');
         embeddedEventSchema.discriminator('Purchased', purchasedSchema.clone());
 
-        var TrackModel = db.model('Track', trackSchema);
-        var doc = new TrackModel({
+        const TrackModel = db.model('Track', trackSchema);
+        const doc = new TrackModel({
           event: {
             message: 'Test',
             kind: 'Purchased'
           }
         });
-        doc.save(function(err){
+        doc.save(function(err) {
           assert.ok(!err);
-          assert.equal(doc.event.message, 'Test')
-          assert.equal(doc.event.kind, 'Purchased')
+          assert.equal(doc.event.message, 'Test');
+          assert.equal(doc.event.kind, 'Purchased');
           Object.keys(counters).forEach(function(i) {
             assert.equal(counters[i], 1, 'Counter ' + i + ' incorrect');
           });
@@ -1268,16 +1268,16 @@ describe('model', function() {
         });
       });
 
-      it('should call the hooks on the embedded document in an embedded array defined by both the parent and discriminated schemas', function(done){
-        var trackSchema = new Schema({
-          events: [eventSchema],
+      it('should call the hooks on the embedded document in an embedded array defined by both the parent and discriminated schemas', function(done) {
+        const trackSchema = new Schema({
+          events: [eventSchema]
         });
 
-        var embeddedEventSchema = trackSchema.path('events');
+        const embeddedEventSchema = trackSchema.path('events');
         embeddedEventSchema.discriminator('Purchased', purchasedSchema.clone());
 
-        var TrackModel = db.model('Track', trackSchema);
-        var doc = new TrackModel({
+        const TrackModel = db.model('Track', trackSchema);
+        const doc = new TrackModel({
           events: [
             {
               message: 'Test',
@@ -1289,7 +1289,7 @@ describe('model', function() {
             }
           ]
         });
-        doc.save(function(err){
+        doc.save(function(err) {
           assert.ok(!err);
           assert.equal(doc.events[0].kind, 'Purchased');
           assert.equal(doc.events[0].message, 'Test');
@@ -1303,8 +1303,8 @@ describe('model', function() {
       });
     });
 
-    it('should copy plugins', function () {
-      const plugin = (schema) => { };
+    it('should copy plugins', function() {
+      const plugin = () => { };
 
       const schema = new Schema({ value: String }, {
         autoIndex: false,
@@ -1326,10 +1326,10 @@ describe('model', function() {
   describe('bug fixes', function() {
     it('discriminators with classes modifies class in place (gh-5175)', function(done) {
       class Vehicle extends mongoose.Model { }
-      var V = mongoose.model(Vehicle, new mongoose.Schema());
+      const V = mongoose.model(Vehicle, new mongoose.Schema());
       assert.ok(V === Vehicle);
       class Car extends Vehicle { }
-      var C = Vehicle.discriminator(Car, new mongoose.Schema());
+      const C = Vehicle.discriminator(Car, new mongoose.Schema());
       assert.ok(C === Car);
       done();
     });
@@ -1358,14 +1358,14 @@ describe('model', function() {
     });
 
     it('supports adding properties (gh-5104) (gh-5635)', function(done) {
-      class Shape extends mongoose.Model { };
-      class Circle extends Shape { };
+      class Shape extends mongoose.Model { }
+      class Circle extends Shape { }
 
       const ShapeModel = mongoose.model(Shape, new mongoose.Schema({
         color: String
       }));
 
-      const CircleModel = ShapeModel.discriminator(Circle, new mongoose.Schema({
+      ShapeModel.discriminator(Circle, new mongoose.Schema({
         radius: Number
       }));
 
@@ -1427,9 +1427,9 @@ describe('model', function() {
         title: String,
         kind: { type: String, required: true }
       }, { discriminatorKey: 'kind' });
-      
+
       const Event = db.model('Test', eventSchema);
-      const Clicked = Event.discriminator('Clicked',
+      Event.discriminator('Clicked',
         Schema({ url: String }));
 
       const doc = new Event({ title: 'foo' });
@@ -1449,7 +1449,7 @@ describe('model', function() {
 
       const documentSchema = Schema({
         title: String,
-        sections: [ sectionSchema ]
+        sections: [sectionSchema]
       });
 
       const sectionsType = documentSchema.path('sections');
@@ -1491,7 +1491,7 @@ describe('model', function() {
       const e = new ClickedLinkEvent({
         lookups: [{
           hi: 'address1',
-          name: 'address2',
+          name: 'address2'
         }],
         url: 'google.com'
       });
@@ -1533,16 +1533,16 @@ describe('model', function() {
         product: { type: Schema.Types.ObjectId, ref: 'Product' }
       });
 
-      const OrderItemSchema = new Schema({}, {discriminatorKey: '__t'});
+      const OrderItemSchema = new Schema({}, { discriminatorKey: '__t' });
 
       const OrderSchema = new Schema({
-        items: [OrderItemSchema],
+        items: [OrderItemSchema]
       });
 
       OrderSchema.path('items').discriminator('ProductItem', ProductItemSchema);
       const Order = db.model('Order', OrderSchema);
 
-      const product = new Product({title: 'Product title'});
+      const product = new Product({ title: 'Product title' });
 
       const order = new Order({
         items: [{
@@ -1557,24 +1557,24 @@ describe('model', function() {
     });
   });
 
-  it('attempting to populate on base model a virtual path defined on discriminator does not throw an error (gh-8924)', function () {
+  it('attempting to populate on base model a virtual path defined on discriminator does not throw an error (gh-8924)', function() {
     return co(function* () {
       const User = db.model('User', {});
       const Post = db.model('Post', {});
-      
+
       const userWithPostSchema = new Schema({ postId: Schema.ObjectId });
-      
+
       userWithPostSchema.virtual('post', { ref: 'Post', localField: 'postId', foreignField: '_id' });
-      
+
       const UserWithPost = User.discriminator('UserWithPost', userWithPostSchema);
-      
+
       const post = yield Post.create({});
-      
+
       yield UserWithPost.create({ postId: post._id });
-      
+
       const user = yield User.findOne().populate({ path: 'post' });
-      
+
       assert.ok(user.postId);
-    })
+    });
   });
 });

From 9341051916896fa831d1b4d5bd87cef2fcae20c7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 12:21:01 +0200
Subject: [PATCH 0856/2348] refactor tests re: #8999

---
 test/aggregate.test.js         | 42 +++++++++++-----------------------
 test/browser.test.js           |  8 +++----
 test/cast.test.js              | 40 +++++++++++---------------------
 test/collection.capped.test.js |  4 ++--
 test/connection.test.js        |  6 ++---
 5 files changed, 34 insertions(+), 66 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 8fc56d44b97..542a44c0ed4 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -430,15 +430,12 @@ describe('aggregate: ', function() {
         });
       });
 
-      it('Throws if no options are passed to graphLookup', function(done) {
+      it('Throws if no options are passed to graphLookup', function() {
         const aggregate = new Aggregate();
-        try {
+        assert.throws(function() {
           aggregate.graphLookup('invalid options');
-          done(new Error('Should have errored'));
-        } catch (error) {
-          assert.ok(error instanceof TypeError);
-          done();
-        }
+        },
+        { name: 'TypeError' });
       });
     });
 
@@ -547,15 +544,11 @@ describe('aggregate: ', function() {
           [{ $sortByCount: { lname: '$employee.last' } }]);
       });
 
-      it('throws if the argument is neither a string or object', function(done) {
+      it('throws if the argument is neither a string or object', function() {
         const aggregate = new Aggregate();
-        try {
+        assert.throws(function() {
           aggregate.sortByCount(1);
-          done(new Error('Should have errored'));
-        } catch (error) {
-          assert.ok(error instanceof TypeError);
-          done();
-        }
+        }, { name: 'TypeError' });
       });
     });
   });
@@ -642,7 +635,7 @@ describe('aggregate: ', function() {
         });
     });
 
-    it('unwind with obj', function(done) {
+    it('unwind with obj', function() {
       const aggregate = new Aggregate();
 
       const agg = aggregate.
@@ -652,10 +645,9 @@ describe('aggregate: ', function() {
       assert.equal(agg._pipeline.length, 1);
       assert.strictEqual(agg._pipeline[0].$unwind.preserveNullAndEmptyArrays,
         true);
-      done();
     });
 
-    it('unwind throws with bad arg', function(done) {
+    it('unwind throws with bad arg', function() {
       const aggregate = new Aggregate();
 
       let threw = false;
@@ -668,7 +660,6 @@ describe('aggregate: ', function() {
         threw = true;
       }
       assert.ok(threw);
-      done();
     });
 
     it('match', function(done) {
@@ -815,7 +806,7 @@ describe('aggregate: ', function() {
         });
     });
 
-    it('pipeline() (gh-5825)', function(done) {
+    it('pipeline() (gh-5825)', function() {
       const aggregate = new Aggregate();
 
       const pipeline = aggregate.
@@ -824,7 +815,6 @@ describe('aggregate: ', function() {
         pipeline();
 
       assert.deepEqual(pipeline, [{ $match: { sal: { $lt: 16000 } } }]);
-      done();
     });
 
     it('explain()', function(done) {
@@ -883,7 +873,7 @@ describe('aggregate: ', function() {
     });
 
     describe('error when not bound to a model', function() {
-      it('with callback', function(done) {
+      it('with callback', function() {
         const aggregate = new Aggregate();
 
         aggregate.skip(0);
@@ -895,8 +885,6 @@ describe('aggregate: ', function() {
           assert.equal(error.message, 'Aggregate not bound to any Model');
         }
         assert.ok(threw);
-
-        done();
       });
     });
 
@@ -1119,7 +1107,7 @@ describe('aggregate: ', function() {
       });
     });
 
-    it('readPref from schema (gh-5522)', function(done) {
+    it('readPref from schema (gh-5522)', function() {
       const schema = new Schema({ name: String }, { read: 'secondary' });
       const M = db.model('Test', schema);
       const a = M.aggregate();
@@ -1128,8 +1116,6 @@ describe('aggregate: ', function() {
       a.read('secondaryPreferred');
 
       assert.equal(a.options.readPreference.mode, 'secondaryPreferred');
-
-      done();
     });
   });
 
@@ -1175,7 +1161,7 @@ describe('aggregate: ', function() {
     });
   });
 
-  it('cursor() with useMongooseAggCursor (gh-5145)', function(done) {
+  it('cursor() with useMongooseAggCursor (gh-5145)', function() {
     const MyModel = db.model('Test', { name: String });
 
     const cursor = MyModel.
@@ -1183,8 +1169,6 @@ describe('aggregate: ', function() {
       cursor({ useMongooseAggCursor: true }).
       exec();
     assert.ok(cursor instanceof require('stream').Readable);
-
-    done();
   });
 
   it('cursor() with useMongooseAggCursor works (gh-5145) (gh-5394)', function(done) {
diff --git a/test/browser.test.js b/test/browser.test.js
index fb0a5d260bc..d60868ae276 100644
--- a/test/browser.test.js
+++ b/test/browser.test.js
@@ -22,16 +22,16 @@ describe('browser', function() {
     exec('node --eval "const mongoose = require(\'./lib/browser\'); new mongoose.Schema();"', done);
   });
 
-  it('document works (gh-4987)', function(done) {
+  it('document works (gh-4987)', function() {
     const schema = new Schema({
       name: { type: String, required: true },
       quest: { type: String, match: /Holy Grail/i, required: true },
       favoriteColor: { type: String, enum: ['Red', 'Blue'], required: true }
     });
 
-    new Document({}, schema);
-
-    done();
+    assert.doesNotThrow(function() {
+      new Document({}, schema);
+    });
   });
 
   it('document validation with arrays (gh-6175)', function() {
diff --git a/test/cast.test.js b/test/cast.test.js
index 6adfa681b17..a5dff289806 100644
--- a/test/cast.test.js
+++ b/test/cast.test.js
@@ -14,51 +14,45 @@ const Buffer = require('safe-buffer').Buffer;
 
 describe('cast: ', function() {
   describe('when casting an array', function() {
-    it('casts array with ObjectIds to $in query', function(done) {
+    it('casts array with ObjectIds to $in query', function() {
       const schema = new Schema({ x: Schema.Types.ObjectId });
       const ids = [new ObjectId(), new ObjectId()];
       assert.deepEqual(cast(schema, { x: ids }), { x: { $in: ids } });
-      done();
     });
 
-    it('casts array with ObjectIds to $in query when values are strings', function(done) {
+    it('casts array with ObjectIds to $in query when values are strings', function() {
       const schema = new Schema({ x: Schema.Types.ObjectId });
       const ids = [new ObjectId(), new ObjectId()];
       assert.deepEqual(cast(schema, { x: ids.map(String) }), { x: { $in: ids } });
-      done();
     });
 
-    it('throws when ObjectIds not valid', function(done) {
+    it('throws when ObjectIds not valid', function() {
       const schema = new Schema({ x: Schema.Types.ObjectId });
       const ids = [123, 456, 'asfds'];
       assert.throws(function() {
         cast(schema, { x: ids });
       }, /Cast to ObjectId failed/);
-      done();
     });
 
-    it('casts array with Strings to $in query', function(done) {
+    it('casts array with Strings to $in query', function() {
       const schema = new Schema({ x: String });
       const strings = ['bleep', 'bloop'];
       assert.deepEqual(cast(schema, { x: strings }), { x: { $in: strings } });
-      done();
     });
 
-    it('casts array with Strings when necessary', function(done) {
+    it('casts array with Strings when necessary', function() {
       const schema = new Schema({ x: String });
       const strings = [123, 456];
       assert.deepEqual(cast(schema, { x: strings }), { x: { $in: strings.map(String) } });
-      done();
     });
 
-    it('casts array with Numbers to $in query', function(done) {
+    it('casts array with Numbers to $in query', function() {
       const schema = new Schema({ x: Number });
       const numbers = [42, 25];
       assert.deepEqual(cast(schema, { x: numbers }), { x: { $in: numbers } });
-      done();
     });
 
-    it('casts $in and $nin with empty array (gh-5913) (gh-7806)', function(done) {
+    it('casts $in and $nin with empty array (gh-5913) (gh-7806)', function() {
       const schema = new Schema({
         v: Number,
         arr: [Number]
@@ -72,55 +66,47 @@ describe('cast: ', function() {
         { v: { $nin: [1, []] } });
       assert.deepEqual(cast(schema, { arr: { $nin: [1, []] } }),
         { arr: { $nin: [1, []] } });
-
-      done();
     });
 
-    it('casts array with Numbers to $in query when values are strings', function(done) {
+    it('casts array with Numbers to $in query when values are strings', function() {
       const schema = new Schema({ x: Number });
       const numbers = ['42', '25'];
       assert.deepEqual(cast(schema, { x: numbers }), { x: { $in: numbers.map(Number) } });
-      done();
     });
 
-    it('throws when Numbers are not valid', function(done) {
+    it('throws when Numbers are not valid', function() {
       const schema = new Schema({ x: Number });
       const numbers = [123, 456, 'asfds'];
       assert.throws(function() {
         cast(schema, { x: numbers });
       }, /Cast to Number failed for value "asfds"/);
-      done();
     });
   });
 
   describe('bitwise query operators: ', function() {
-    it('with a number', function(done) {
+    it('with a number', function() {
       const schema = new Schema({ x: Buffer });
       assert.deepEqual(cast(schema, { x: { $bitsAllClear: 3 } }),
         { x: { $bitsAllClear: 3 } });
-      done();
     });
 
-    it('with an array', function(done) {
+    it('with an array', function() {
       const schema = new Schema({ x: Buffer });
       assert.deepEqual(cast(schema, { x: { $bitsAllSet: [2, '3'] } }),
         { x: { $bitsAllSet: [2, 3] } });
-      done();
     });
 
-    it('with a buffer', function(done) {
+    it('with a buffer', function() {
       const schema = new Schema({ x: Number });
       assert.deepEqual(cast(schema, { x: { $bitsAnyClear: Buffer.from([3]) } }),
         { x: { $bitsAnyClear: Buffer.from([3]) } });
-      done();
     });
 
-    it('throws when invalid', function(done) {
+    it('throws when invalid', function() {
       const schema = new Schema({ x: Number });
       assert.throws(function() {
         cast(schema, { x: { $bitsAnySet: 'Not a number' } });
       }, /Cast to number failed/);
-      done();
     });
   });
 });
diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index 330593063cc..a0270fa47a2 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -28,14 +28,14 @@ describe('collections: capped:', function() {
     db.close(done);
   });
 
-  it('schemas should have option size', function(done) {
+  it('schemas should have option size', function() {
     const capped = new Schema({ key: String });
     capped.set('capped', { size: 1000 });
 
     assert.ok(capped.options.capped);
     assert.equal(capped.options.capped.size, 1000);
-    done();
   });
+
   it('creation', function() {
     this.timeout(30000);
 
diff --git a/test/connection.test.js b/test/connection.test.js
index 152e3142781..42b6a29791e 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -119,18 +119,16 @@ describe('connections:', function() {
       conn.then(() => done(), err => done(err));
     });
 
-    it('throws helpful error with legacy syntax (gh-6756)', function(done) {
+    it('throws helpful error with legacy syntax (gh-6756)', function() {
       assert.throws(function() {
         mongoose.createConnection('localhost', 'dbname', 27017);
       }, /mongoosejs\.com.*connections\.html/);
-      done();
     });
 
-    it('throws helpful error with undefined uri (gh-6763)', function(done) {
+    it('throws helpful error with undefined uri (gh-6763)', function() {
       assert.throws(function() {
         mongoose.createConnection(void 0, { useNewUrlParser: true });
       }, /string.*createConnection/);
-      done();
     });
 
     it('resolving with q (gh-5714)', function(done) {

From 46f33455d5b167383ade682174c63aeeec095311 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 12:25:35 +0200
Subject: [PATCH 0857/2348] tests: refactor tests re #8999

---
 test/document.test.js            | 16 +++++++-----
 test/index.test.js               |  6 +++--
 test/model.discriminator.test.js | 23 ++++++++---------
 test/schema.test.js              | 12 +++++----
 test/schematype.cast.test.js     | 42 +++++++++++++++++++++-----------
 5 files changed, 61 insertions(+), 38 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index cb1b3976ffc..e2d236b8586 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -4457,8 +4457,9 @@ describe('document', function() {
           return Test.findById(doc._id);
         }).
         then(function(doc) {
-          // Should not throw
-          require('util').inspect(doc);
+          assert.doesNotThrow(function() {
+            require('util').inspect(doc);
+          });
           done();
         }).
         catch(done);
@@ -4988,8 +4989,9 @@ describe('document', function() {
 
       assert.deepEqual(doc.toObject({ virtuals: true }).tests, ['a', 'b']);
 
-      // Should not throw
-      require('util').inspect(doc);
+      assert.doesNotThrow(function() {
+        require('util').inspect(doc);
+      });
       JSON.stringify(doc);
 
       done();
@@ -7389,7 +7391,9 @@ describe('document', function() {
 
     assert.equal(cu.profile.name, 'foo');
     assert.equal(cu.profile.email, 'bar');
-    cu.toObject(); // shouldn't throw
+    assert.doesNotThrow(function() {
+      cu.toObject();
+    });
   });
 
   it('setting single nested subdoc with custom date types and getters/setters (gh-7601)', function() {
@@ -9000,4 +9004,4 @@ describe('document', function() {
       assert.ok(!user.updatedAt);
     });
   });
-});
+});
\ No newline at end of file
diff --git a/test/index.test.js b/test/index.test.js
index a8025689c86..1c4ab109019 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -148,7 +148,9 @@ describe('mongoose module:', function() {
     const s = new Schema({});
     const M = mongoose.model('Test', s);
     assert.ok(M.schema !== s);
-    mongoose.model('Test', M.schema); // Shouldn't throw
+    assert.doesNotThrow(function() {
+      mongoose.model('Test', M.schema);
+    });
 
     mongoose.set('cloneSchemas', false);
 
@@ -779,4 +781,4 @@ describe('mongoose module:', function() {
       });
     });
   });
-});
+});
\ No newline at end of file
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 4bf886e5f5b..1c8ba262794 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -251,9 +251,10 @@ describe('model', function() {
         department: String
       }, { id: false });
 
-      // Should not throw
-      var Person = db.model('Test1', PersonSchema);
-      Person.discriminator('Boss', BossSchema);
+      assert.doesNotThrow(function () {
+        var Person = db.model('Test1', PersonSchema);
+        Person.discriminator('Boss', BossSchema);
+      });
       done();
     });
 
@@ -442,10 +443,9 @@ describe('model', function() {
             somethingElse: {type: String}
           });
 
-          // Should not throw
-          const SubModel = Model.discriminator('TestSub', subSchema);
-
-          return Promise.resolve();
+          assert.doesNotThrow(function(){
+            Model.discriminator('TestSub', subSchema);
+          })
         });
       });
 
@@ -614,8 +614,10 @@ describe('model', function() {
 
         var Person = db.model('Person', personSchema);
         var Parent = Person.discriminator('Parent', parentSchema.clone());
-        // Should not throw
-        var Parent2 = Person.discriminator('Parent2', parentSchema.clone());
+        
+        assert.doesNotThrow(function () {
+         Person.discriminator('Parent2', parentSchema.clone());
+        });
         done();
       });
 
@@ -756,7 +758,6 @@ describe('model', function() {
           info: 'AAAAAAAAAAAAAAAAAAAAAAAA',
         });
 
-        // Should not throw
         assert.ifError(d1.validateSync());
 
         done();
@@ -1577,4 +1578,4 @@ describe('model', function() {
       assert.ok(user.postId);
     })
   });
-});
+});
\ No newline at end of file
diff --git a/test/schema.test.js b/test/schema.test.js
index 0a1e00f6b80..6b9d878f224 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1745,8 +1745,9 @@ describe('schema', function() {
       this.schema.methods.toString = function() {
         return 'test';
       };
-      // should not throw
-      mongoose.model('gh4551', this.schema);
+      assert.doesNotThrow(function() {
+        mongoose.model('gh4551', this.schema);
+      });
       done();
     });
 
@@ -1897,8 +1898,9 @@ describe('schema', function() {
         const schema = new db.Schema({ name: MyType });
         const otherSchema = schema.clone();
 
-        // Should not throw
-        otherSchema.add({ name2: MyType });
+        assert.doesNotThrow(function() {
+          otherSchema.add({ name2: MyType });
+        });
       });
 
       it('clones schema types (gh-7537)', function() {
@@ -2430,4 +2432,4 @@ describe('schema', function() {
       assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
     });
   });
-});
+});
\ No newline at end of file
diff --git a/test/schematype.cast.test.js b/test/schematype.cast.test.js
index 2f89b53cd9c..b0ec4fe30cb 100644
--- a/test/schematype.cast.test.js
+++ b/test/schematype.cast.test.js
@@ -44,11 +44,11 @@ describe('SchemaType.cast() (gh-7045)', function() {
       assert.equal(error.name, 'CastError');
     }
 
-    objectid.cast('000000000000000000000000'); // Should not throw
-
-    // Base objectid shouldn't throw
-    baseObjectId.cast('12charstring');
-    baseObjectId.cast('000000000000000000000000');
+    assert.doesNotThrow(function() {
+      objectid.cast('000000000000000000000000');
+      baseObjectId.cast('12charstring');
+      baseObjectId.cast('000000000000000000000000');
+    });
 
     assert.ok(threw);
   });
@@ -119,8 +119,9 @@ describe('SchemaType.cast() (gh-7045)', function() {
       assert.equal(error.name, 'CastError');
     }
     assert.ok(threw);
-
-    b.cast(true); // Should not throw
+    assert.doesNotThrow(function() {
+      b.cast(true);
+    });
   });
 
   describe('string', function() {
@@ -131,7 +132,9 @@ describe('SchemaType.cast() (gh-7045)', function() {
       });
 
       const s = new Schema.Types.String();
-      s.cast('short'); // Should not throw
+      assert.doesNotThrow(function() {
+        s.cast('short');
+      });
 
       assert.throws(() => s.cast('wayyyy too long'), /CastError/);
     });
@@ -140,7 +143,10 @@ describe('SchemaType.cast() (gh-7045)', function() {
       Schema.Types.String.cast(false);
 
       const s = new Schema.Types.String();
-      s.cast('short'); // Should not throw
+
+      assert.doesNotThrow(function() {
+        s.cast('short');
+      });
 
       assert.throws(() => s.cast(123), /CastError/);
     });
@@ -154,8 +160,10 @@ describe('SchemaType.cast() (gh-7045)', function() {
       });
 
       const d = new Schema.Types.Date();
-      d.cast('2018-06-01'); // Should not throw
-      d.cast(new Date()); // Should not throw
+      assert.doesNotThrow(function() {
+        d.cast('2018-06-01');
+        d.cast(new Date());
+      });
 
       assert.throws(() => d.cast(''), /CastError/);
     });
@@ -164,7 +172,9 @@ describe('SchemaType.cast() (gh-7045)', function() {
       Schema.Types.Date.cast(false);
 
       const d = new Schema.Types.Date();
-      d.cast(new Date()); // Should not throw
+      assert.doesNotThrow(function() {
+        d.cast(new Date());
+      });
 
       assert.throws(() => d.cast('2018-06-01'), /CastError/);
     });
@@ -178,7 +188,9 @@ describe('SchemaType.cast() (gh-7045)', function() {
       });
 
       const d = new Schema.Types.Decimal128();
-      d.cast('1000'); // Should not throw
+      assert.doesNotThrow(function() {
+        d.cast('1000');
+      });
 
       assert.throws(() => d.cast(1000), /CastError/);
     });
@@ -190,7 +202,9 @@ describe('SchemaType.cast() (gh-7045)', function() {
       assert.throws(() => d.cast('1000'), /CastError/);
       assert.throws(() => d.cast(1000), /CastError/);
 
-      d.cast(original.decimal128('1000')); // Should not throw
+      assert.doesNotThrow(function() {
+        d.cast(original.decimal128('1000'));
+      });
     });
   });
 });
\ No newline at end of file

From 6521507e7285775f98c64160894184d4d3cfee81 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 12:35:34 +0200
Subject: [PATCH 0858/2348] refactor more tests re: #8999

---
 test/collection.test.js          |  3 +-
 test/connection.test.js          | 54 ++++++++++----------------------
 test/document.isselected.test.js |  8 ++---
 3 files changed, 20 insertions(+), 45 deletions(-)

diff --git a/test/collection.test.js b/test/collection.test.js
index 79ac6adf822..1afb5741b63 100644
--- a/test/collection.test.js
+++ b/test/collection.test.js
@@ -59,7 +59,7 @@ describe('collections:', function() {
     });
   });
 
-  it('methods should that throw (unimplemented)', function(done) {
+  it('methods should that throw (unimplemented)', function() {
     const collection = new Collection('test', mongoose.connection);
     let thrown = false;
 
@@ -142,6 +142,5 @@ describe('collections:', function() {
 
     assert.ok(thrown);
     thrown = false;
-    done();
   });
 });
diff --git a/test/connection.test.js b/test/connection.test.js
index 42b6a29791e..f259e6d590f 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -447,7 +447,7 @@ describe('connections:', function() {
     assert.equal(db.port, 27017);
   });
 
-  it('should accept unix domain sockets', function(done) {
+  it('should accept unix domain sockets', function() {
     const host = encodeURIComponent('/tmp/mongodb-27017.sock');
     const db = mongoose.createConnection(`mongodb://aaron:psw@${host}/fake`, { useNewUrlParser: true });
     db.catch(() => {});
@@ -456,7 +456,6 @@ describe('connections:', function() {
     assert.equal(db.pass, 'psw');
     assert.equal(db.user, 'aaron');
     db.close();
-    done();
   });
 
   describe('errors', function() {
@@ -555,7 +554,7 @@ describe('connections:', function() {
       db.deleteModel(/.*/);
     });
 
-    it('allows passing a schema', function(done) {
+    it('allows passing a schema', function() {
       const MyModel = mongoose.model('Test', new Schema({
         name: String
       }));
@@ -565,48 +564,40 @@ describe('connections:', function() {
 
       const m = new MyModel({ name: 'aaron' });
       assert.equal(m.name, 'aaron');
-      done();
     });
 
-    it('should properly assign the db', function(done) {
+    it('should properly assign the db', function() {
       const A = mongoose.model('testing853a', new Schema({ x: String }), 'testing853-1');
       const B = mongoose.model('testing853b', new Schema({ x: String }), 'testing853-2');
       const C = B.model('testing853a');
       assert.ok(C === A);
-      done();
     });
 
-    it('prevents overwriting pre-existing models', function(done) {
+    it('prevents overwriting pre-existing models', function() {
       db.deleteModel(/Test/);
       db.model('Test', new Schema);
 
       assert.throws(function() {
         db.model('Test', new Schema);
       }, /Cannot overwrite `Test` model/);
-
-      done();
     });
 
-    it('allows passing identical name + schema args', function(done) {
+    it('allows passing identical name + schema args', function() {
       const name = 'Test';
       const schema = new Schema;
 
       db.deleteModel(/Test/);
       const model = db.model(name, schema);
       db.model(name, model.schema);
-
-      done();
     });
 
-    it('throws on unknown model name', function(done) {
+    it('throws on unknown model name', function() {
       assert.throws(function() {
         db.model('iDoNotExist!');
       }, /Schema hasn't been registered/);
-
-      done();
     });
 
-    it('uses the passed schema when global model exists with same name (gh-1209)', function(done) {
+    it('uses the passed schema when global model exists with same name (gh-1209)', function() {
       const s1 = new Schema({ one: String });
       const s2 = new Schema({ two: Number });
 
@@ -628,22 +619,20 @@ describe('connections:', function() {
       assert.ok(C.schema === A.schema);
 
       db.close();
-      done();
     });
 
     describe('get existing model with not existing collection in db', function() {
-      it('must return exiting collection with all collection options', function(done) {
+      it('must return exiting collection with all collection options', function() {
         mongoose.model('some-th-1458', new Schema({ test: String }, { capped: { size: 1000, max: 10 } }));
         const m = db.model('some-th-1458');
         assert.equal(1000, m.collection.opts.capped.size);
         assert.equal(10, m.collection.opts.capped.max);
-        done();
       });
     });
 
     describe('passing collection name', function() {
       describe('when model name already exists', function() {
-        it('returns a new uncached model', function(done) {
+        it('returns a new uncached model', function() {
           const s1 = new Schema({ a: [] });
           const name = 'Test';
           const A = db.model(name, s1);
@@ -653,7 +642,6 @@ describe('connections:', function() {
           assert.ok(A.collection.name !== C.collection.name);
           assert.ok(db.models[name].collection.name !== C.collection.name);
           assert.ok(db.models[name].collection.name === A.collection.name);
-          done();
         });
       });
     });
@@ -1038,32 +1026,29 @@ describe('connections:', function() {
   describe('shouldAuthenticate()', function() {
     describe('when using standard authentication', function() {
       describe('when username and password are undefined', function() {
-        it('should return false', function(done) {
+        it('should return false', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {});
 
           assert.equal(db.shouldAuthenticate(), false);
 
           db.close();
-          done();
         });
       });
       describe('when username and password are empty strings', function() {
-        it('should return false', function(done) {
+        it('should return false', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {
             user: '',
             pass: ''
           });
-          db.on('error', function() {
-          });
+          db.on('error', function() {});
 
           assert.equal(db.shouldAuthenticate(), false);
 
           db.close();
-          done();
         });
       });
       describe('when both username and password are defined', function() {
-        it('should return true', function(done) {
+        it('should return true', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {
             user: 'user',
             pass: 'pass'
@@ -1073,13 +1058,12 @@ describe('connections:', function() {
           assert.equal(db.shouldAuthenticate(), true);
 
           db.close();
-          done();
         });
       });
     });
     describe('when using MONGODB-X509 authentication', function() {
       describe('when username and password are undefined', function() {
-        it('should return false', function(done) {
+        it('should return false', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {});
           db.on('error', function() {
           });
@@ -1087,11 +1071,10 @@ describe('connections:', function() {
           assert.equal(db.shouldAuthenticate(), false);
 
           db.close();
-          done();
         });
       });
       describe('when only username is defined', function() {
-        it('should return false', function(done) {
+        it('should return false', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {
             user: 'user',
             auth: { authMechanism: 'MONGODB-X509' }
@@ -1100,11 +1083,10 @@ describe('connections:', function() {
           assert.equal(db.shouldAuthenticate(), true);
 
           db.close();
-          done();
         });
       });
       describe('when both username and password are defined', function() {
-        it('should return false', function(done) {
+        it('should return false', function() {
           const db = mongoose.createConnection('mongodb://localhost:27017/fake', {
             user: 'user',
             pass: 'pass',
@@ -1115,20 +1097,18 @@ describe('connections:', function() {
           assert.equal(db.shouldAuthenticate(), true);
 
           db.close();
-          done();
         });
       });
     });
   });
 
   describe('passing a function into createConnection', function() {
-    it('should store the name of the function (gh-6517)', function(done) {
+    it('should store the name of the function (gh-6517)', function() {
       const conn = mongoose.createConnection('mongodb://localhost:27017/gh6517');
       const schema = new Schema({ name: String });
       class Person extends mongoose.Model {}
       conn.model(Person, schema);
       assert.strictEqual(conn.modelNames()[0], 'Person');
-      done();
     });
   });
 
diff --git a/test/document.isselected.test.js b/test/document.isselected.test.js
index ef199240a6a..70d4abb9277 100644
--- a/test/document.isselected.test.js
+++ b/test/document.isselected.test.js
@@ -97,7 +97,7 @@ TestDocument.prototype.hooksTest = function(fn) {
  * Test.
  */
 describe('document', function() {
-  it('isSelected()', function(done) {
+  it('isSelected()', function() {
     let doc = new TestDocument();
 
     doc.init({
@@ -332,11 +332,9 @@ describe('document', function() {
     assert.ok(!doc.isSelected('nested'));
     assert.ok(!doc.isSelected('nested.age'));
     assert.ok(!doc.isSelected('numbers'));
-
-    done();
   });
 
-  it('isDirectSelected (gh-5063)', function(done) {
+  it('isDirectSelected (gh-5063)', function() {
     const selection = {
       test: 1,
       numbers: 1,
@@ -357,7 +355,5 @@ describe('document', function() {
     assert.ok(doc.isDirectSelected('nested.deep'));
     assert.ok(!doc.isDirectSelected('nested.cool'));
     assert.ok(!doc.isDirectSelected('nested'));
-
-    done();
   });
 });

From c312a9cd9d5e1b4c9e068cd19ee57e0470989389 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 12:43:58 +0200
Subject: [PATCH 0859/2348] test: refactor more tests re: #8999

---
 test/document.modified.test.js | 45 ++++++------------
 test/document.populate.test.js | 10 ++--
 test/document.strict.test.js   | 28 ++++--------
 test/document.test.js          | 83 +++++++++++-----------------------
 4 files changed, 51 insertions(+), 115 deletions(-)

diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 0d344d8d61c..1e5336df3fa 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -123,31 +123,24 @@ describe('document modified', function() {
   });
 
   describe('isDefault', function() {
-    it('works', function(done) {
+    it('works', function() {
       const MyModel = db.model('Test',
         { name: { type: String, default: 'Val ' } });
       const m = new MyModel();
       assert.ok(m.$isDefault('name'));
-      done();
     });
   });
 
   describe('isModified', function() {
-    it('should not throw with no argument', function(done) {
+    it('should not throw with no argument', function() {
       const post = new BlogPost;
 
-      let threw = false;
-      try {
+      assert.doesNotThrow(function() {
         post.isModified();
-      } catch (err) {
-        threw = true;
-      }
-
-      assert.equal(threw, false);
-      done();
+      });
     });
 
-    it('when modifying keys', function(done) {
+    it('when modifying keys', function() {
       const post = new BlogPost;
       post.init({
         title: 'Test',
@@ -164,10 +157,9 @@ describe('document modified', function() {
       assert.equal(post.isModified('date'), true);
 
       assert.equal(post.isModified('meta.date'), false);
-      done();
     });
 
-    it('setting a key identically to its current value should not dirty the key', function(done) {
+    it('setting a key identically to its current value should not dirty the key', function() {
       const post = new BlogPost;
       post.init({
         title: 'Test',
@@ -178,11 +170,10 @@ describe('document modified', function() {
       assert.equal(post.isModified('title'), false);
       post.set('title', 'Test');
       assert.equal(post.isModified('title'), false);
-      done();
     });
 
     describe('on DocumentArray', function() {
-      it('work', function(done) {
+      it('work', function() {
         const post = new BlogPost();
         post.init({
           title: 'Test',
@@ -196,10 +187,8 @@ describe('document modified', function() {
         assert.equal(post.isDirectModified('comments'), false);
         assert.equal(post.isModified('comments.0.title'), true);
         assert.equal(post.isDirectModified('comments.0.title'), true);
-
-        done();
       });
-      it('with accessors', function(done) {
+      it('with accessors', function() {
         const post = new BlogPost();
         post.init({
           title: 'Test',
@@ -213,23 +202,19 @@ describe('document modified', function() {
         assert.equal(post.isDirectModified('comments'), false);
         assert.equal(post.isModified('comments.0.body'), true);
         assert.equal(post.isDirectModified('comments.0.body'), true);
-
-        done();
       });
     });
 
     describe('on MongooseArray', function() {
-      it('atomic methods', function(done) {
+      it('atomic methods', function() {
         const post = new BlogPost();
         assert.equal(post.isModified('owners'), false);
         post.get('owners').push(new DocumentObjectId);
         assert.equal(post.isModified('owners'), true);
-        done();
       });
-      it('native methods', function(done) {
+      it('native methods', function() {
         const post = new BlogPost;
         assert.equal(post.isModified('owners'), false);
-        done();
       });
     });
 
@@ -335,7 +320,7 @@ describe('document modified', function() {
       });
     });
 
-    it('properly sets populated for gh-1530 (gh-2678)', function(done) {
+    it('properly sets populated for gh-1530 (gh-2678)', function() {
       const parentSchema = new Schema({
         name: String,
         child: { type: Schema.Types.ObjectId, ref: 'Child' }
@@ -348,7 +333,6 @@ describe('document modified', function() {
       const p = new Parent({ name: 'Alex', child: child });
 
       assert.equal(child._id.toString(), p.populated('child').toString());
-      done();
     });
 
     describe('manually populating arrays', function() {
@@ -362,7 +346,7 @@ describe('document modified', function() {
         db.close(done);
       });
 
-      it('gh-1530 for arrays (gh-3575)', function(done) {
+      it('gh-1530 for arrays (gh-3575)', function() {
         const parentSchema = new Schema({
           name: String,
           children: [{ type: Schema.Types.ObjectId, ref: 'Child' }]
@@ -376,7 +360,6 @@ describe('document modified', function() {
 
         assert.equal('Luke', p.children[0].name);
         assert.ok(p.populated('children'));
-        done();
       });
 
       it('setting nested arrays (gh-3721)', function() {
@@ -405,7 +388,7 @@ describe('document modified', function() {
         return Promise.all([User.init(), Account.init()]);
       });
 
-      it('with discriminators (gh-3575)', function(done) {
+      it('with discriminators (gh-3575)', function() {
         const shapeSchema = new mongoose.Schema({}, { discriminatorKey: 'kind' });
 
         db.deleteModel(/Test/);
@@ -430,8 +413,6 @@ describe('document modified', function() {
         assert.ok(test.populated('bars'));
         assert.ok(test.bars[0]._id);
         assert.ok(test.bars[1]._id);
-
-        done();
       });
 
       it('updates embedded doc parents upon direct assignment (gh-5189)', function(done) {
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index 3873320cee1..4e7c7e3930b 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -200,11 +200,10 @@ describe('document.populate', function() {
       });
     });
 
-    it('are not modified when no arguments are passed', function(done) {
+    it('are not modified when no arguments are passed', function() {
       const d = new TestDocument();
       const o = utils.clone(d.options);
       assert.deepEqual(o, d.populate().options);
-      done();
     });
   });
 
@@ -498,7 +497,7 @@ describe('document.populate', function() {
     });
   });
 
-  it('depopulates when setting `_id` (gh-3308)', function(done) {
+  it('depopulates when setting `_id` (gh-3308)', function() {
     const Person = db.model('Person', {
       name: String
     });
@@ -517,8 +516,6 @@ describe('document.populate', function() {
     const buckethead = new Person({ name: 'Buckethead' });
     gnr.guitarist = buckethead._id;
     assert.ok(!gnr.populated('guitarist'));
-
-    done();
   });
 
   describe('gh-2214', function() {
@@ -799,7 +796,7 @@ describe('document.populate', function() {
     });
   });
 
-  it('does not allow you to call populate() on nested docs (gh-4552)', function(done) {
+  it('does not allow you to call populate() on nested docs (gh-4552)', function() {
     const EmbeddedSchema = new Schema({
       reference: {
         type: mongoose.Schema.ObjectId,
@@ -818,7 +815,6 @@ describe('document.populate', function() {
     assert.throws(function() {
       m.embedded.populate('reference');
     }, /on nested docs/);
-    done();
   });
 
   it('handles pulling from populated array (gh-3579)', function(done) {
diff --git a/test/document.strict.test.js b/test/document.strict.test.js
index 2a98ec12072..f6401010227 100644
--- a/test/document.strict.test.js
+++ b/test/document.strict.test.js
@@ -73,7 +73,7 @@ describe('document: strict mode:', function() {
       });
     });
 
-    it('when creating models with strict schemas', function(done) {
+    it('when creating models with strict schemas', function() {
       const s = new Strict({ content: 'sample', rouge: 'data' });
       assert.equal(s.$__.strictMode, true);
 
@@ -86,10 +86,9 @@ describe('document: strict mode:', function() {
       assert.ok(!('rouge' in so));
       assert.ok(!s.rouge);
       assert.ok(!so.rouge);
-      done();
     });
 
-    it('when overriding strictness', function(done) {
+    it('when overriding strictness', function() {
       // instance override
       let instance = new Lax({ content: 'sample', rouge: 'data' }, true);
       assert.ok(instance.$__.strictMode);
@@ -114,7 +113,6 @@ describe('document: strict mode:', function() {
       assert.equal(s3.content, 'sample');
       assert.ok(!('rouge' in s3));
       assert.ok(!s3.rouge);
-      done();
     });
 
     it('when using Model#create', function(done) {
@@ -128,7 +126,7 @@ describe('document: strict mode:', function() {
     });
   });
 
-  it('nested doc', function(done) {
+  it('nested doc', function() {
     const lax = new Schema({
       name: { last: String }
     }, { strict: false });
@@ -161,7 +159,6 @@ describe('document: strict mode:', function() {
     assert.ok(!('hack' in s.name));
     assert.ok(!s.name.hack);
     assert.ok(!s.shouldnt);
-    done();
   });
 
   it('sub doc', function(done) {
@@ -210,7 +207,7 @@ describe('document: strict mode:', function() {
     });
   });
 
-  it('virtuals', function(done) {
+  it('virtuals', function() {
     let getCount = 0,
         setCount = 0;
 
@@ -248,8 +245,6 @@ describe('document: strict mode:', function() {
     assert.equal('string', typeof temp);
     assert.equal(getCount, 1);
     assert.equal(setCount, 2);
-
-    done();
   });
 
   it('can be overridden during set()', function(done) {
@@ -355,7 +350,7 @@ describe('document: strict mode:', function() {
   });
 
   describe('"throws" mode', function() {
-    it('throws on set() of unknown property', function(done) {
+    it('throws on set() of unknown property', function() {
       const schema = new Schema({ n: String, docs: [{ x: [{ y: String }] }] });
       schema.set('strict', 'throw');
       const M = db.model('Test', schema);
@@ -398,11 +393,9 @@ describe('document: strict mode:', function() {
       assert.throws(function() {
         m.set('docs.0.x.4.y.z', 3);
       }, badField);
-
-      done();
     });
 
-    it('fails with extra fields', function(done) {
+    it('fails with extra fields', function() {
       // Simple schema with throws option
       const FooSchema = new mongoose.Schema({
         name: { type: String }
@@ -419,11 +412,9 @@ describe('document: strict mode:', function() {
         // The extra baz field should throw
         new Foo({ name: 'bar', baz: 'bam' });
       }, /Field `baz` is not in schema/);
-
-      done();
     });
 
-    it('doesnt throw with refs (gh-2665)', function(done) {
+    it('doesnt throw with refs (gh-2665)', function() {
       // Simple schema with throws option
       const FooSchema = new mongoose.Schema({
         name: { type: mongoose.Schema.Types.ObjectId, ref: 'test', required: false, default: null },
@@ -436,11 +427,9 @@ describe('document: strict mode:', function() {
       assert.doesNotThrow(function() {
         new Foo({ name: mongoose.Types.ObjectId(), father: { name: { full: 'bacon' } } });
       });
-
-      done();
     });
 
-    it('set nested to num throws ObjectExpectedError (gh-3735)', function(done) {
+    it('set nested to num throws ObjectExpectedError (gh-3735)', function() {
       const schema = new Schema({
         resolved: {
           by: { type: String }
@@ -452,7 +441,6 @@ describe('document: strict mode:', function() {
       assert.throws(function() {
         new Test({ resolved: 123 });
       }, /ObjectExpectedError/);
-      done();
     });
   });
 
diff --git a/test/document.test.js b/test/document.test.js
index e2d236b8586..35b49971ca4 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -219,14 +219,13 @@ describe('document', function() {
   });
 
   describe('shortcut getters', function() {
-    it('return undefined for properties with a null/undefined parent object (gh-1326)', function(done) {
+    it('return undefined for properties with a null/undefined parent object (gh-1326)', function() {
       const doc = new TestDocument;
       doc.init({ nested: null });
       assert.strictEqual(undefined, doc.nested.age);
-      done();
     });
 
-    it('work', function(done) {
+    it('work', function() {
       const doc = new TestDocument();
       doc.init({
         test: 'test',
@@ -299,11 +298,10 @@ describe('document', function() {
       assert.equal(String(doc2.nested.cool), '4cf70857337498f95900001c');
 
       assert.ok(doc.oids !== doc2.oids);
-      done();
     });
   });
 
-  it('test shortcut setters', function(done) {
+  it('test shortcut setters', function() {
     const doc = new TestDocument();
 
     doc.init({
@@ -328,22 +326,19 @@ describe('document', function() {
     assert.equal(Object.keys(doc._doc.nested).length, 1);
     assert.equal(doc.nested.path, 'overwrite the entire nested object');
     assert.ok(doc.isModified('nested'));
-    done();
   });
 
-  it('test accessor of id', function(done) {
+  it('test accessor of id', function() {
     const doc = new TestDocument();
     assert.ok(doc._id instanceof DocumentObjectId);
-    done();
   });
 
-  it('test shortcut of id hexString', function(done) {
+  it('test shortcut of id hexString', function() {
     const doc = new TestDocument();
     assert.equal(typeof doc.id, 'string');
-    done();
   });
 
-  it('toObject options', function(done) {
+  it('toObject options', function() {
     const doc = new TestDocument();
 
     doc.init({
@@ -498,7 +493,6 @@ describe('document', function() {
 
     // all done
     delete doc.schema.options.toObject;
-    done();
   });
 
   it('toObject transform', function(done) {
@@ -700,7 +694,7 @@ describe('document', function() {
       });
     });
 
-    it('handles child schema transforms', function(done) {
+    it('handles child schema transforms', function() {
       const userSchema = new Schema({
         name: String,
         email: String
@@ -736,7 +730,6 @@ describe('document', function() {
       assert.equal(output.email, 'a@b.co');
       assert.equal(output.followers[0].name, 'Val');
       assert.equal(output.followers[0].email, undefined);
-      done();
     });
 
     it('doesnt clobber child schema options when called with no params (gh-2035)', function(done) {
@@ -784,7 +777,7 @@ describe('document', function() {
   });
 
   describe('toJSON', function() {
-    it('toJSON options', function(done) {
+    it('toJSON options', function() {
       const doc = new TestDocument();
 
       doc.init({
@@ -910,10 +903,9 @@ describe('document', function() {
 
       // all done
       delete doc.schema.options.toJSON;
-      done();
     });
 
-    it('jsonifying an object', function(done) {
+    it('jsonifying an object', function() {
       const doc = new TestDocument({ test: 'woot' });
       const oidString = doc._id.toString();
       // convert to json string
@@ -923,7 +915,6 @@ describe('document', function() {
 
       assert.equal(obj.test, 'woot');
       assert.equal(obj._id, oidString);
-      done();
     });
 
     it('jsonifying an object\'s populated items works (gh-1376)', function(done) {
@@ -1067,12 +1058,11 @@ describe('document', function() {
   });
 
   describe.skip('#update', function() {
-    it('returns a Query', function(done) {
+    it('returns a Query', function() {
       const mg = new mongoose.Mongoose;
       const M = mg.model('Test', { s: String });
       const doc = new M;
       assert.ok(doc.update() instanceof Query);
-      done();
     });
     it('calling update on document should relay to its model (gh-794)', function(done) {
       const Docs = new Schema({ text: String });
@@ -1100,31 +1090,28 @@ describe('document', function() {
     });
   });
 
-  it('toObject should not set undefined values to null', function(done) {
+  it('toObject should not set undefined values to null', function() {
     const doc = new TestDocument();
     const obj = doc.toObject();
 
     delete obj._id;
     assert.deepEqual(obj, { numbers: [], oids: [], em: [] });
-    done();
   });
 
   describe('Errors', function() {
-    it('MongooseErrors should be instances of Error (gh-209)', function(done) {
+    it('MongooseErrors should be instances of Error (gh-209)', function() {
       const MongooseError = require('../lib/error');
       const err = new MongooseError('Some message');
       assert.ok(err instanceof Error);
-      done();
     });
-    it('ValidationErrors should be instances of Error', function(done) {
+    it('ValidationErrors should be instances of Error', function() {
       const ValidationError = Document.ValidationError;
       const err = new ValidationError(new TestDocument);
       assert.ok(err instanceof Error);
-      done();
     });
   });
 
-  it('methods on embedded docs should work', function(done) {
+  it('methods on embedded docs should work', function() {
     const ESchema = new Schema({ name: String });
 
     ESchema.methods.test = function() {
@@ -1150,10 +1137,9 @@ describe('document', function() {
     assert.equal(typeof p.embed[0].test, 'function');
     assert.equal(typeof E.ten, 'function');
     assert.equal(p.embed[0].test(), 'apple butter');
-    done();
   });
 
-  it('setting a positional path does not cast value to array', function(done) {
+  it('setting a positional path does not cast value to array', function() {
     const doc = new TestDocument;
     doc.init({ numbers: [1, 3] });
     assert.equal(doc.numbers[0], 1);
@@ -1161,10 +1147,9 @@ describe('document', function() {
     doc.set('numbers.1', 2);
     assert.equal(doc.numbers[0], 1);
     assert.equal(doc.numbers[1], 2);
-    done();
   });
 
-  it('no maxListeners warning should occur', function(done) {
+  it('no maxListeners warning should occur', function() {
     let traced = false;
     const trace = console.trace;
 
@@ -1192,7 +1177,6 @@ describe('document', function() {
 
     new S({ title: 'test' });
     assert.equal(traced, false);
-    done();
   });
 
   it('unselected required fields should pass validation', function(done) {
@@ -1601,19 +1585,17 @@ describe('document', function() {
         M = db.model('Test5', new Schema({ name: String }, { _id: false }));
       });
 
-      it('with string _ids', function(done) {
+      it('with string _ids', function() {
         const s1 = new S({ _id: 'one' });
         const s2 = new S({ _id: 'one' });
         assert.ok(s1.equals(s2));
-        done();
       });
-      it('with number _ids', function(done) {
+      it('with number _ids', function() {
         const n1 = new N({ _id: 0 });
         const n2 = new N({ _id: 0 });
         assert.ok(n1.equals(n2));
-        done();
       });
-      it('with ObjectId _ids', function(done) {
+      it('with ObjectId _ids', function() {
         let id = new mongoose.Types.ObjectId;
         let o1 = new O({ _id: id });
         let o2 = new O({ _id: id });
@@ -1623,28 +1605,25 @@ describe('document', function() {
         o1 = new O({ _id: id });
         o2 = new O({ _id: id });
         assert.ok(o1.equals(o2));
-        done();
       });
-      it('with Buffer _ids', function(done) {
+      it('with Buffer _ids', function() {
         const n1 = new B({ _id: 0 });
         const n2 = new B({ _id: 0 });
         assert.ok(n1.equals(n2));
-        done();
       });
-      it('with _id disabled (gh-1687)', function(done) {
+      it('with _id disabled (gh-1687)', function() {
         const m1 = new M;
         const m2 = new M;
         assert.doesNotThrow(function() {
           m1.equals(m2);
         });
-        done();
       });
     });
   });
 
   describe('setter', function() {
     describe('order', function() {
-      it('is applied correctly', function(done) {
+      it('is applied correctly', function() {
         const date = 'Thu Aug 16 2012 09:45:59 GMT-0700';
         const d = new TestDocument();
         dateSetterCalled = false;
@@ -1654,7 +1633,6 @@ describe('document', function() {
         assert.ok(d._doc.date instanceof Date);
         assert.ok(d.date instanceof Date);
         assert.equal(+d.date, +new Date(date));
-        done();
       });
     });
 
@@ -1673,7 +1651,7 @@ describe('document', function() {
 
     describe('on nested paths', function() {
       describe('using set(path, object)', function() {
-        it('overwrites the entire object', function(done) {
+        it('overwrites the entire object', function() {
           let doc = new TestDocument();
 
           doc.init({
@@ -1755,8 +1733,6 @@ describe('document', function() {
           assert.ok(!doc.isModified('nested.age'));
           assert.ok(doc.isModified('nested.deep'));
           assert.equal(doc.nested.deep.x, 'Hank and Marie');
-
-          done();
         });
 
         it('allows positional syntax on mixed nested paths (gh-6738)', function() {
@@ -1772,7 +1748,7 @@ describe('document', function() {
           assert.strictEqual(doc.nested.a.b.c.d.e.f, 'g');
         });
 
-        it('gh-1954', function(done) {
+        it('gh-1954', function() {
           const schema = new Schema({
             schedule: [new Schema({ open: Number, close: Number })]
           });
@@ -1793,19 +1769,16 @@ describe('document', function() {
           assert.ok(doc.schedule[0] instanceof EmbeddedDocument);
           assert.equal(doc.schedule[0].open, 1100);
           assert.equal(doc.schedule[0].close, 1900);
-
-          done();
         });
       });
 
       describe('when overwriting with a document instance', function() {
-        it('does not cause StackOverflows (gh-1234)', function(done) {
+        it('does not cause StackOverflows (gh-1234)', function() {
           const doc = new TestDocument({ nested: { age: 35 } });
           doc.nested = doc.nested;
           assert.doesNotThrow(function() {
             doc.nested.age;
           });
-          done();
         });
       });
     });
@@ -1816,7 +1789,7 @@ describe('document', function() {
       let val;
       let M;
 
-      beforeEach(function(done) {
+      beforeEach(function() {
         const schema = new mongoose.Schema({ v: Number });
         schema.virtual('thang').set(function(v) {
           val = v;
@@ -1824,13 +1797,11 @@ describe('document', function() {
 
         db.deleteModel(/Test/);
         M = db.model('Test', schema);
-        done();
       });
 
-      it('works with objects', function(done) {
+      it('works with objects', function() {
         new M({ thang: {} });
         assert.deepEqual({}, val);
-        done();
       });
       it('works with arrays', function(done) {
         new M({ thang: [] });

From 1ee8c9cebdf3b9321b56ee60a613ea4045f97dd0 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 12:52:14 +0200
Subject: [PATCH 0860/2348] test: refactor more tests re: #8999

---
 test/document.test.js | 84 ++++++++++++++-----------------------------
 1 file changed, 27 insertions(+), 57 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 35b49971ca4..4c54dffc19f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -1803,20 +1803,17 @@ describe('document', function() {
         new M({ thang: {} });
         assert.deepEqual({}, val);
       });
-      it('works with arrays', function(done) {
+      it('works with arrays', function() {
         new M({ thang: [] });
         assert.deepEqual([], val);
-        done();
       });
-      it('works with numbers', function(done) {
+      it('works with numbers', function() {
         new M({ thang: 4 });
         assert.deepEqual(4, val);
-        done();
       });
-      it('works with strings', function(done) {
+      it('works with strings', function() {
         new M({ thang: '3' });
         assert.deepEqual('3', val);
-        done();
       });
     });
 
@@ -2071,7 +2068,7 @@ describe('document', function() {
     });
   });
 
-  it('properly calls queue functions (gh-2856)', function(done) {
+  it('properly calls queue functions (gh-2856)', function() {
     const personSchema = new mongoose.Schema({
       name: String
     });
@@ -2085,7 +2082,6 @@ describe('document', function() {
     const Person = db.model('Person', personSchema);
     new Person({ name: 'Val' });
     assert.equal(calledName, 'Val');
-    done();
   });
 
   describe('bug fixes', function() {
@@ -2177,7 +2173,7 @@ describe('document', function() {
         });
     });
 
-    it('setters firing with objects on real paths (gh-2943)', function(done) {
+    it('setters firing with objects on real paths (gh-2943)', function() {
       const M = db.model('Test', {
         myStr: {
           type: String, set: function(v) {
@@ -2192,12 +2188,10 @@ describe('document', function() {
 
       new M({ otherStr: { value: 'test' } });
       assert.ok(!t.otherStr);
-
-      done();
     });
 
     describe('gh-2782', function() {
-      it('should set data from a sub doc', function(done) {
+      it('should set data from a sub doc', function() {
         const schema1 = new mongoose.Schema({
           data: {
             email: String
@@ -2214,11 +2208,10 @@ describe('document', function() {
         const doc2 = new Model2();
         doc2.set(doc1.data);
         assert.equal(doc2.email, 'some@example.com');
-        done();
       });
     });
 
-    it('set data from subdoc keys (gh-3346)', function(done) {
+    it('set data from subdoc keys (gh-3346)', function() {
       const schema1 = new mongoose.Schema({
         data: {
           email: String
@@ -2230,7 +2223,6 @@ describe('document', function() {
       assert.equal(doc1.data.email, 'some@example.com');
       const doc2 = new Model1({ data: doc1.data });
       assert.equal(doc2.data.email, 'some@example.com');
-      done();
     });
 
     it('doesnt attempt to cast generic objects as strings (gh-3030)', function(done) {
@@ -2293,7 +2285,7 @@ describe('document', function() {
       });
     });
 
-    it('single embedded schemas with validation (gh-2689)', function(done) {
+    it('single embedded schemas with validation (gh-2689)', function() {
       const userSchema = new mongoose.Schema({
         name: String,
         email: { type: String, required: true, match: /.+@.+/ }
@@ -2318,11 +2310,9 @@ describe('document', function() {
       assert.ok(error);
       assert.ok(error.errors['user.email']);
       assert.equal(error.errors['user.email'].kind, 'regexp');
-
-      done();
     });
 
-    it('single embedded parent() (gh-5134)', function(done) {
+    it('single embedded parent() (gh-5134)', function() {
       const userSchema = new mongoose.Schema({
         name: String,
         email: { type: String, required: true, match: /.+@.+/ }
@@ -2337,8 +2327,6 @@ describe('document', function() {
 
       const e = new Event({ name: 'test', user: {} });
       assert.strictEqual(e.user.parent(), e.user.ownerDocument());
-
-      done();
     });
 
     it('single embedded schemas with markmodified (gh-2689)', function(done) {
@@ -2615,7 +2603,7 @@ describe('document', function() {
       });
     });
 
-    it('single embedded schemas with methods (gh-3534)', function(done) {
+    it('single embedded schemas with methods (gh-3534)', function() {
       const personSchema = new Schema({ name: String });
       personSchema.methods.firstName = function() {
         return this.name.substr(0, this.name.indexOf(' '));
@@ -2626,7 +2614,6 @@ describe('document', function() {
 
       const gnr = new Band({ leadSinger: { name: 'Axl Rose' } });
       assert.equal(gnr.leadSinger.firstName(), 'Axl');
-      done();
     });
 
     it('single embedded schemas with models (gh-3535)', function(done) {
@@ -2646,7 +2633,7 @@ describe('document', function() {
       });
     });
 
-    it('single embedded schemas with indexes (gh-3594)', function(done) {
+    it('single embedded schemas with indexes (gh-3594)', function() {
       const personSchema = new Schema({ name: { type: String, unique: true } });
 
       const bandSchema = new Schema({ leadSinger: personSchema });
@@ -2655,7 +2642,6 @@ describe('document', function() {
       const index = bandSchema.indexes()[0];
       assert.deepEqual(index[0], { 'leadSinger.name': 1 });
       assert.ok(index[1].unique);
-      done();
     });
 
     it('removing single embedded docs (gh-3596)', function(done) {
@@ -2807,7 +2793,7 @@ describe('document', function() {
       });
     });
 
-    it('handles virtuals with dots correctly (gh-3618)', function(done) {
+    it('handles virtuals with dots correctly (gh-3618)', function() {
       const testSchema = new Schema({ nested: { type: Object, default: {} } });
       testSchema.virtual('nested.test').get(function() {
         return true;
@@ -2826,7 +2812,6 @@ describe('document', function() {
       delete doc._id;
       delete doc.id;
       assert.deepEqual(doc, { nested: { test: true } });
-      done();
     });
 
     it('handles pushing with numeric keys (gh-3623)', function(done) {
@@ -2917,7 +2902,7 @@ describe('document', function() {
       });
     });
 
-    it('handles conflicting names (gh-3867)', function(done) {
+    it('handles conflicting names (gh-3867)', function() {
       const testSchema = new Schema({
         name: {
           type: String,
@@ -2939,7 +2924,6 @@ describe('document', function() {
 
       const fields = Object.keys(doc.validateSync().errors).sort();
       assert.deepEqual(fields, ['name', 'things.0.name']);
-      done();
     });
 
     it('populate with lean (gh-3873)', function(done) {
@@ -3186,7 +3170,7 @@ describe('document', function() {
       });
     });
 
-    it('skip validation if required returns false (gh-4094)', function(done) {
+    it('skip validation if required returns false (gh-4094)', function() {
       const schema = new Schema({
         div: {
           type: Number,
@@ -3197,7 +3181,6 @@ describe('document', function() {
       const Model = db.model('Test', schema);
       const m = new Model();
       assert.ifError(m.validateSync());
-      done();
     });
 
     it('ability to overwrite array default (gh-4109)', function(done) {
@@ -3285,7 +3268,7 @@ describe('document', function() {
         catch(done);
     });
 
-    it('single embedded with defaults have $parent (gh-4115)', function(done) {
+    it('single embedded with defaults have $parent (gh-4115)', function() {
       const ChildSchema = new Schema({
         name: {
           type: String,
@@ -3304,7 +3287,6 @@ describe('document', function() {
 
       const p = new Parent();
       assert.equal(p.child.$parent, p);
-      done();
     });
 
     it('removing parent doc calls remove hooks on subdocs (gh-2348) (gh-4566)', function(done) {
@@ -3537,19 +3519,16 @@ describe('document', function() {
       });
     });
 
-    it('minimize + empty object (gh-4337)', function(done) {
+    it('minimize + empty object (gh-4337)', function() {
       const SomeModelSchema = new mongoose.Schema({}, {
         minimize: false
       });
 
       const SomeModel = db.model('Test', SomeModelSchema);
 
-      try {
+      assert.doesNotThrow(function() {
         new SomeModel({});
-      } catch (error) {
-        assert.ifError(error);
-      }
-      done();
+      });
     });
 
     it('directModifiedPaths() (gh-7373)', function() {
@@ -3587,7 +3566,7 @@ describe('document', function() {
         });
       });
 
-      it('includeChildren option (gh-6134)', function(done) {
+      it('includeChildren option (gh-6134)', function() {
         const personSchema = new mongoose.Schema({
           name: { type: String },
           colors: {
@@ -3616,11 +3595,9 @@ describe('document', function() {
         const anakin = new Person({ name: 'Anakin' });
         anakin.colors = { primary: 'blue' };
         assert.deepEqual(anakin.modifiedPaths({ includeChildren: true }), ['name', 'colors', 'colors.primary']);
-
-        done();
       });
 
-      it('includeChildren option with arrays (gh-5904)', function(done) {
+      it('includeChildren option with arrays (gh-5904)', function() {
         const teamSchema = new mongoose.Schema({
           name: String,
           colors: {
@@ -3653,8 +3630,6 @@ describe('document', function() {
           'members.0',
           'members.0.name'
         ]);
-
-        done();
       });
 
       it('1 level down nested paths get marked modified on initial set (gh-7313) (gh-6944)', function() {
@@ -3716,7 +3691,7 @@ describe('document', function() {
       });
     });
 
-    it('deep default array values (gh-4540)', function(done) {
+    it('deep default array values (gh-4540)', function() {
       const schema = new Schema({
         arr: [{
           test: {
@@ -3728,7 +3703,6 @@ describe('document', function() {
       assert.doesNotThrow(function() {
         db.model('Test', schema);
       });
-      done();
     });
 
     it('default values with subdoc array (gh-4390)', function(done) {
@@ -3769,7 +3743,7 @@ describe('document', function() {
       });
     });
 
-    it('setting array subpath (gh-4472)', function(done) {
+    it('setting array subpath (gh-4472)', function() {
       const ChildSchema = new mongoose.Schema({
         name: String,
         age: Number
@@ -3790,7 +3764,6 @@ describe('document', function() {
       });
 
       assert.deepEqual(p.toObject().data.children, [{ name: 'Bob', age: 900 }]);
-      done();
     });
 
     it('ignore paths (gh-4480)', function() {
@@ -3882,7 +3855,7 @@ describe('document', function() {
         catch(done);
     });
 
-    it('validateSync with undefined and conditional required (gh-4607)', function(done) {
+    it('validateSync with undefined and conditional required (gh-4607)', function() {
       const schema = new mongoose.Schema({
         type: mongoose.SchemaTypes.Number,
         conditional: {
@@ -3902,11 +3875,9 @@ describe('document', function() {
           conditional: void 0
         }).validateSync();
       });
-
-      done();
     });
 
-    it('conditional required on single nested (gh-4663)', function(done) {
+    it('conditional required on single nested (gh-4663)', function() {
       const childSchema = new Schema({
         name: String
       });
@@ -3921,8 +3892,8 @@ describe('document', function() {
 
       const M = db.model('Test', schema);
 
-      new M({ child: { name: 'test' } }).validateSync();
-      done();
+      const err = new M({ child: { name: 'test' } }).validateSync();
+      assert.ifError(err);
     });
 
     it('setting full path under single nested schema works (gh-4578) (gh-4528)', function(done) {
@@ -3981,7 +3952,7 @@ describe('document', function() {
       });
     });
 
-    it('toObject() does not depopulate top level (gh-3057)', function(done) {
+    it('toObject() does not depopulate top level (gh-3057)', function() {
       const Cat = db.model('Cat', { name: String });
       const Human = db.model('Person', {
         name: String,
@@ -3993,7 +3964,6 @@ describe('document', function() {
 
       assert.equal(kitty.toObject({ depopulate: true }).name, 'Zildjian');
       assert.ok(!person.toObject({ depopulate: true }).petCat.name);
-      done();
     });
 
     it('toObject() respects schema-level depopulate (gh-6313)', function(done) {

From a0c740ea06e59e84aa292b07906489b9154b41cc Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 12:57:09 +0200
Subject: [PATCH 0861/2348] fix tests for node 4 re #8999

---
 test/aggregate.test.js | 4 ++--
 test/schema.test.js    | 5 ++---
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/test/aggregate.test.js b/test/aggregate.test.js
index 542a44c0ed4..3c0239b26ca 100644
--- a/test/aggregate.test.js
+++ b/test/aggregate.test.js
@@ -435,7 +435,7 @@ describe('aggregate: ', function() {
         assert.throws(function() {
           aggregate.graphLookup('invalid options');
         },
-        { name: 'TypeError' });
+        TypeError);
       });
     });
 
@@ -548,7 +548,7 @@ describe('aggregate: ', function() {
         const aggregate = new Aggregate();
         assert.throws(function() {
           aggregate.sortByCount(1);
-        }, { name: 'TypeError' });
+        }, TypeError);
       });
     });
   });
diff --git a/test/schema.test.js b/test/schema.test.js
index 6b9d878f224..15b5d67370e 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1741,14 +1741,13 @@ describe('schema', function() {
       done();
     });
 
-    it('methods named toString (gh-4551)', function(done) {
+    it('methods named toString (gh-4551)', function() {
       this.schema.methods.toString = function() {
         return 'test';
       };
-      assert.doesNotThrow(function() {
+      assert.doesNotThrow(() => {
         mongoose.model('gh4551', this.schema);
       });
-      done();
     });
 
     it('handles default value = 0 (gh-4620)', function(done) {

From dd01f03cd44a0cc5362481d6fb9da1fa9d0a00a4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 14 May 2020 15:11:42 +0200
Subject: [PATCH 0862/2348] test: refactor more tests re #8999

---
 test/document.test.js      | 89 +++++++++++---------------------------
 test/document.unit.test.js | 12 ++---
 test/index.test.js         | 46 ++++++--------------
 3 files changed, 42 insertions(+), 105 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 4c54dffc19f..9abe72654cc 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -3966,7 +3966,7 @@ describe('document', function() {
       assert.ok(!person.toObject({ depopulate: true }).petCat.name);
     });
 
-    it('toObject() respects schema-level depopulate (gh-6313)', function(done) {
+    it('toObject() respects schema-level depopulate (gh-6313)', function() {
       const personSchema = Schema({
         name: String,
         car: {
@@ -3996,7 +3996,6 @@ describe('document', function() {
       });
 
       assert.equal(person.toObject().car.toHexString(), car._id.toHexString());
-      done();
     });
 
     it('single nested doc conditional required (gh-4654)', function(done) {
@@ -4202,7 +4201,7 @@ describe('document', function() {
         catch(done);
     });
 
-    it('handles setting virtual subpaths (gh-4716)', function(done) {
+    it('handles setting virtual subpaths (gh-4716)', function() {
       const childSchema = new Schema({
         name: { type: String, default: 'John' },
         favorites: {
@@ -4232,7 +4231,6 @@ describe('document', function() {
       p.set('children.0.name', 'Leah');
       p.set('favorites.color', 'Red');
       assert.equal(p.children[0].favorites.color, 'Red');
-      done();
     });
 
     it('handles selected nested elements with defaults (gh-4739)', function(done) {
@@ -4258,7 +4256,7 @@ describe('document', function() {
       });
     });
 
-    it('handles mark valid in subdocs correctly (gh-4778)', function(done) {
+    it('handles mark valid in subdocs correctly (gh-4778)', function() {
       const SubSchema = new mongoose.Schema({
         field: {
           nestedField: {
@@ -4283,7 +4281,6 @@ describe('document', function() {
       doc.sub.field.nestedField = { };
       doc.sub.field.nestedField = '574b69d0d9daf106aaa62974';
       assert.ok(!doc.validateSync());
-      done();
     });
 
     it('timestamps set to false works (gh-7074)', function() {
@@ -4317,7 +4314,7 @@ describe('document', function() {
       });
     });
 
-    it('Declaring defaults in your schema with timestamps defined (gh-6024)', function(done) {
+    it('Declaring defaults in your schema with timestamps defined (gh-6024)', function() {
       const schemaDefinition = {
         name: String,
         misc: {
@@ -4330,8 +4327,6 @@ describe('document', function() {
       const PersonWithTimestamps = db.model('Person', schemaWithTimestamps);
       const dude = new PersonWithTimestamps({ name: 'Keanu', misc: { hometown: 'Beirut' } });
       assert.equal(dude.misc.isAlive, true);
-
-      done();
     });
 
     it('supports $where in pre save hook (gh-4004)', function(done) {
@@ -4406,7 +4401,7 @@ describe('document', function() {
         catch(done);
     });
 
-    it('buffer subtype prop (gh-5530)', function(done) {
+    it('buffer subtype prop (gh-5530)', function() {
       const TestSchema = new mongoose.Schema({
         uuid: {
           type: Buffer,
@@ -4418,7 +4413,6 @@ describe('document', function() {
 
       const doc = new Test({ uuid: 'test1' });
       assert.equal(doc.uuid._subtype, 4);
-      done();
     });
 
     it('runs validate hooks on single nested subdocs if not directly modified (gh-3884)', function(done) {
@@ -4571,7 +4565,7 @@ describe('document', function() {
       return Promise.resolve();
     });
 
-    it('does not overwrite when setting nested (gh-4793)', function(done) {
+    it('does not overwrite when setting nested (gh-4793)', function() {
       const grandchildSchema = new mongoose.Schema();
       grandchildSchema.method({
         foo: function() { return 'bar'; }
@@ -4597,7 +4591,6 @@ describe('document', function() {
 
       assert.equal(child.grandchild.foo(), 'bar');
       assert.equal(p.children[0].grandchild.foo(), 'bar');
-      done();
     });
 
     it('hooks/middleware for custom methods (gh-6385) (gh-7456)', function() {
@@ -4700,7 +4693,7 @@ describe('document', function() {
       });
     });
 
-    it('toString() as custom method (gh-6538)', function(done) {
+    it('toString() as custom method (gh-6538)', function() {
       const commentSchema = new Schema({ title: String });
       commentSchema.methods.toString = function() {
         return `${this.constructor.modelName}(${this.title})`;
@@ -4708,10 +4701,9 @@ describe('document', function() {
       const Comment = db.model('Comment', commentSchema);
       const c = new Comment({ title: 'test' });
       assert.strictEqual('Comment(test)', `${c}`);
-      done();
     });
 
-    it('setting to discriminator (gh-4935)', function(done) {
+    it('setting to discriminator (gh-4935)', function() {
       const Buyer = db.model('Test1', new Schema({
         name: String,
         vehicle: { type: Schema.Types.ObjectId, ref: 'Test' }
@@ -4728,8 +4720,6 @@ describe('document', function() {
       assert.ok(nick.vehicle === eleanor);
       assert.ok(nick.vehicle instanceof Car);
       assert.equal(nick.vehicle.name, 'Eleanor');
-
-      done();
     });
 
     it('handles errors in sync validators (gh-2185)', function(done) {
@@ -4841,7 +4831,7 @@ describe('document', function() {
         then(doc => assert.equal(doc.sub.val, 'test'));
     });
 
-    it('nested docs toObject() clones (gh-5008)', function(done) {
+    it('nested docs toObject() clones (gh-5008)', function() {
       const schema = new mongoose.Schema({
         sub: {
           height: Number
@@ -4864,11 +4854,9 @@ describe('document', function() {
       doc.sub.height = 55;
       assert.equal(doc.sub.height, 55);
       assert.equal(leanDoc.height, 3);
-
-      done();
     });
 
-    it('toObject() with null (gh-5143)', function(done) {
+    it('toObject() with null (gh-5143)', function() {
       const schema = new mongoose.Schema({
         customer: {
           name: { type: String, required: false }
@@ -4881,11 +4869,9 @@ describe('document', function() {
       model.customer = null;
       assert.strictEqual(model.toObject().customer, null);
       assert.strictEqual(model.toObject({ getters: true }).customer, null);
-
-      done();
     });
 
-    it('handles array subdocs with single nested subdoc default (gh-5162)', function(done) {
+    it('handles array subdocs with single nested subdoc default (gh-5162)', function() {
       const RatingsItemSchema = new mongoose.Schema({
         value: Number
       }, { versionKey: false, _id: false });
@@ -4909,10 +4895,9 @@ describe('document', function() {
       // Should not throw
       const r = new Restaurant();
       assert.deepEqual(r.toObject().menu, []);
-      done();
     });
 
-    it('iterating through nested doc keys (gh-5078)', function(done) {
+    it('iterating through nested doc keys (gh-5078)', function() {
       const schema = new Schema({
         nested: {
           test1: String,
@@ -4934,11 +4919,9 @@ describe('document', function() {
         require('util').inspect(doc);
       });
       JSON.stringify(doc);
-
-      done();
     });
 
-    it('deeply nested virtual paths (gh-5250)', function(done) {
+    it('deeply nested virtual paths (gh-5250)', function() {
       const TestSchema = new Schema({});
       TestSchema.
         virtual('a.b.c').
@@ -4952,8 +4935,6 @@ describe('document', function() {
       const TestModel = db.model('Test', TestSchema);
       const t = new TestModel({ 'a.b.c': 5 });
       assert.equal(t.a.b.c, 5);
-
-      done();
     });
 
     it('nested virtual when populating with parent projected out (gh-7491)', function() {
@@ -5184,7 +5165,7 @@ describe('document', function() {
       });
     });
 
-    it('setting populated path with typeKey (gh-5313)', function(done) {
+    it('setting populated path with typeKey (gh-5313)', function() {
       const personSchema = Schema({
         name: { $type: String },
         favorite: { $type: Schema.Types.ObjectId, ref: 'Book' },
@@ -5209,8 +5190,6 @@ describe('document', function() {
 
       assert.equal(person.books[0].title, 'The Jungle Book');
       assert.equal(person.books[1].title, '1984');
-
-      done();
     });
 
     it('save twice with write concern (gh-5294)', function(done) {
@@ -5254,7 +5233,7 @@ describe('document', function() {
       });
     });
 
-    it('dotted virtuals in toObject (gh-5473)', function(done) {
+    it('dotted virtuals in toObject (gh-5473)', function() {
       const schema = new mongoose.Schema({}, {
         toObject: { virtuals: true },
         toJSON: { virtuals: true }
@@ -5278,7 +5257,6 @@ describe('document', function() {
         b: 2
       });
       assert.equal(m.toObject({ virtuals: false }).test, void 0);
-      done();
     });
 
     it('dotted virtuals in toObject (gh-5506)', function(done) {
@@ -5315,7 +5293,7 @@ describe('document', function() {
         catch(done);
     });
 
-    it('parent props not in child (gh-5470)', function(done) {
+    it('parent props not in child (gh-5470)', function() {
       const employeeSchema = new mongoose.Schema({
         name: {
           first: String,
@@ -5337,7 +5315,6 @@ describe('document', function() {
       assert.ok(ownPropertyNames.indexOf('department') === -1, ownPropertyNames.join(','));
       assert.ok(ownPropertyNames.indexOf('first') !== -1, ownPropertyNames.join(','));
       assert.ok(ownPropertyNames.indexOf('last') !== -1, ownPropertyNames.join(','));
-      done();
     });
 
     it('modifying array with existing ids (gh-5523)', function(done) {
@@ -5544,7 +5521,7 @@ describe('document', function() {
       });
     });
 
-    it('push populated doc onto empty array triggers manual population (gh-5504)', function(done) {
+    it('push populated doc onto empty array triggers manual population (gh-5504)', function() {
       const ReferringSchema = new Schema({
         reference: [{
           type: Schema.Types.ObjectId,
@@ -5578,8 +5555,6 @@ describe('document', function() {
 
       referrerE.reference.addToSet(referenceB);
       assert.ok(referrerE.reference[0] instanceof Referrer);
-
-      done();
     });
 
     it('single nested conditional required scope (gh-5569)', function(done) {
@@ -5620,7 +5595,7 @@ describe('document', function() {
       });
     });
 
-    it('single nested setters only get called once (gh-5601)', function(done) {
+    it('single nested setters only get called once (gh-5601)', function() {
       const vals = [];
       const ChildSchema = new mongoose.Schema({
         number: {
@@ -5646,7 +5621,6 @@ describe('document', function() {
       p.child = { number: '555.555.0123' };
       assert.equal(vals.length, 1);
       assert.equal(vals[0], '555.555.0123');
-      done();
     });
 
     it('single getters only get called once (gh-7442)', function() {
@@ -5724,7 +5698,7 @@ describe('document', function() {
       });
     });
 
-    it('handles array defaults correctly (gh-5780)', function(done) {
+    it('handles array defaults correctly (gh-5780)', function() {
       const testSchema = new Schema({
         nestedArr: {
           type: [[Number]],
@@ -5740,8 +5714,6 @@ describe('document', function() {
       t.nestedArr.push([1, 2]);
       const t2 = new Test({});
       assert.deepEqual(t2.toObject().nestedArr, [[0, 1]]);
-
-      done();
     });
 
     it('sets path to the empty string on save after query (gh-6477)', function() {
@@ -5806,7 +5778,7 @@ describe('document', function() {
       });
     });
 
-    it('virtuals with no getters return undefined (gh-6223)', function(done) {
+    it('virtuals with no getters return undefined (gh-6223)', function() {
       const personSchema = new mongoose.Schema({
         name: { type: String },
         children: [{
@@ -5835,11 +5807,9 @@ describe('document', function() {
       assert.strictEqual(person.favoriteChild, void 0);
       assert.ok(!('favoriteChild' in person.toJSON()));
       assert.ok(!('favoriteChild' in person.toObject()));
-
-      done();
     });
 
-    it('add default getter/setter (gh-6262)', function(done) {
+    it('add default getter/setter (gh-6262)', function() {
       const testSchema = new mongoose.Schema({});
 
       testSchema.virtual('totalValue');
@@ -5852,8 +5822,6 @@ describe('document', function() {
       const doc = new Test();
       doc.totalValue = 5;
       assert.equal(doc.totalValue, 5);
-
-      done();
     });
 
     it('nested virtuals + nested toJSON (gh-6294)', function() {
@@ -5881,7 +5849,7 @@ describe('document', function() {
       });
     });
 
-    it('Disallows writing to __proto__ and other special properties', function(done) {
+    it('Disallows writing to __proto__ and other special properties', function() {
       const schema = new mongoose.Schema({
         name: String
       }, { strict: false });
@@ -5897,8 +5865,6 @@ describe('document', function() {
       doc.set('constructor.prototype.z', 'baz');
 
       assert.strictEqual(Model.z, void 0);
-
-      done();
     });
 
     it('save() depopulates pushed arrays (gh-6048)', function() {
@@ -6277,7 +6243,7 @@ describe('document', function() {
       });
     });
 
-    it('accessing arrays in setters on initial document creation (gh-6155)', function(done) {
+    it('accessing arrays in setters on initial document creation (gh-6155)', function() {
       const artistSchema = new mongoose.Schema({
         name: {
           type: String,
@@ -6296,11 +6262,9 @@ describe('document', function() {
 
       const artist = new Artist({ name: 'Motley Crue' });
       assert.deepEqual(artist.toObject().keywords, ['Motley', 'Crue']);
-
-      done();
     });
 
-    it('handles 2nd level nested field with null child (gh-6187)', function(done) {
+    it('handles 2nd level nested field with null child (gh-6187)', function() {
       const NestedSchema = new Schema({
         parent: new Schema({
           name: String,
@@ -6318,8 +6282,6 @@ describe('document', function() {
       });
 
       assert.equal(n.parent.name, 'foo');
-
-      done();
     });
 
     it('does not call default function on init if value set (gh-6410)', function() {
@@ -6543,7 +6505,7 @@ describe('document', function() {
       delete Array.prototype.remove;
     });
 
-    it('handles clobbered Array.prototype.remove (gh-6431)', function(done) {
+    it('handles clobbered Array.prototype.remove (gh-6431)', function() {
       Object.defineProperty(Array.prototype, 'remove', {
         value: 42,
         configurable: true,
@@ -6555,7 +6517,6 @@ describe('document', function() {
 
       const doc = new MyModel();
       assert.deepEqual(doc.toObject().arr, []);
-      done();
     });
 
     it('calls array validators again after save (gh-6818)', function() {
diff --git a/test/document.unit.test.js b/test/document.unit.test.js
index 874c93674d0..bc7fbd3bc50 100644
--- a/test/document.unit.test.js
+++ b/test/document.unit.test.js
@@ -12,7 +12,7 @@ const storeShard = require('../lib/plugins/sharding').storeShard;
 const mongoose = start.mongoose;
 
 describe('sharding', function() {
-  it('should handle shard keys properly (gh-2127)', function(done) {
+  it('should handle shard keys properly (gh-2127)', function() {
     const mockSchema = {
       options: {
         shardKey: { date: 1 }
@@ -29,7 +29,6 @@ describe('sharding', function() {
 
     storeShard.call(d);
     assert.equal(d.$__.shardval.date, currentTime);
-    done();
   });
 });
 
@@ -49,24 +48,21 @@ describe('toObject()', function() {
     Stub.prototype = Object.create(mongoose.Document.prototype);
   });
 
-  it('should inherit options from schema', function(done) {
+  it('should inherit options from schema', function() {
     const d = new Stub();
     assert.deepEqual(d.toObject(), { empty: {}, virtual: 'test' });
-    done();
   });
 
-  it('can overwrite schema-set default options', function(done) {
+  it('can overwrite schema-set default options', function() {
     const d = new Stub();
     assert.deepEqual(d.toObject({ minimize: true, virtuals: false }), {});
-    done();
   });
 
-  it('doesnt crash with empty object (gh-3130)', function(done) {
+  it('doesnt crash with empty object (gh-3130)', function() {
     const d = new Stub();
     d._doc = undefined;
     assert.doesNotThrow(function() {
       d.toObject();
     });
-    done();
   });
 });
diff --git a/test/index.test.js b/test/index.test.js
index 1c4ab109019..da4df5de6c4 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -44,26 +44,24 @@ describe('mongoose module:', function() {
     });
   });
 
-  it('legacy pluralize by default (gh-5958)', function(done) {
+  it('legacy pluralize by default (gh-5958)', function() {
     const mongoose = new Mongoose();
 
     mongoose.model('User', new Schema({}));
 
     assert.equal(mongoose.model('User').collection.name, 'users');
-    done();
   });
 
-  it('returns legacy pluralize function by default', function(done) {
+  it('returns legacy pluralize function by default', function() {
     const legacyPluralize = require('mongoose-legacy-pluralize');
     const mongoose = new Mongoose();
 
     const pluralize = mongoose.pluralize();
 
     assert.equal(pluralize, legacyPluralize);
-    done();
   });
 
-  it('sets custom pluralize function (gh-5877)', function(done) {
+  it('sets custom pluralize function (gh-5877)', function() {
     const mongoose = new Mongoose();
 
     // some custom function of type (str: string) => string
@@ -75,7 +73,6 @@ describe('mongoose module:', function() {
 
     mongoose.model('User', new Schema({}));
     assert.equal(mongoose.model('User').collection.name, 'User');
-    done();
   });
 
   it('debug to stream (gh-7018)', function() {
@@ -100,7 +97,7 @@ describe('mongoose module:', function() {
     });
   });
 
-  it('{g,s}etting options', function(done) {
+  it('{g,s}etting options', function() {
     const mongoose = new Mongoose();
 
     mongoose.set('runValidators', 'b');
@@ -109,17 +106,14 @@ describe('mongoose module:', function() {
     assert.equal(mongoose.get('runValidators'), 'b');
     assert.equal(mongoose.set('runValidators'), 'b');
     assert.equal(mongoose.get('useNewUrlParser'), 'c');
-    done();
   });
 
-  it('allows `const { model } = mongoose` (gh-3768)', function(done) {
+  it('allows `const { model } = mongoose` (gh-3768)', function() {
     const model = mongoose.model;
 
     model('gh3768', new Schema({ name: String }));
 
     assert.ok(mongoose.models['gh3768']);
-
-    done();
   });
 
   it('options object (gh-8144)', function() {
@@ -128,7 +122,7 @@ describe('mongoose module:', function() {
     assert.strictEqual(mongoose.options.bufferCommands, false);
   });
 
-  it('bufferCommands option (gh-5879)', function(done) {
+  it('bufferCommands option (gh-5879)', function() {
     const mongoose = new Mongoose();
 
     mongoose.set('bufferCommands', false);
@@ -136,11 +130,9 @@ describe('mongoose module:', function() {
     const M = mongoose.model('Test', new Schema({}));
 
     assert.ok(!M.collection.buffer);
-
-    done();
   });
 
-  it('cloneSchemas option (gh-6274)', function(done) {
+  it('cloneSchemas option (gh-6274)', function() {
     const mongoose = new Mongoose();
 
     mongoose.set('cloneSchemas', true);
@@ -156,11 +148,9 @@ describe('mongoose module:', function() {
 
     const M2 = mongoose.model('Test2', s);
     assert.ok(M2.schema === s);
-
-    done();
   });
 
-  it('objectIdGetter option (gh-6588)', function(done) {
+  it('objectIdGetter option (gh-6588)', function() {
     const mongoose = new Mongoose();
 
     let o = new mongoose.Types.ObjectId();
@@ -175,8 +165,6 @@ describe('mongoose module:', function() {
 
     o = new mongoose.Types.ObjectId();
     assert.strictEqual(o._id, o);
-
-    done();
   });
 
   it('runValidators option (gh-6865) (gh-6578)', function() {
@@ -221,7 +209,7 @@ describe('mongoose module:', function() {
       });
   });
 
-  it('toJSON options (gh-6815)', function(done) {
+  it('toJSON options (gh-6815)', function() {
     const mongoose = new Mongoose();
 
     mongoose.set('toJSON', { virtuals: true });
@@ -243,11 +231,9 @@ describe('mongoose module:', function() {
     doc = new M2();
     assert.equal(doc.toJSON({ virtuals: false }).foo, void 0);
     assert.equal(doc.toJSON().foo, 'bar');
-
-    done();
   });
 
-  it('toObject options (gh-6815)', function(done) {
+  it('toObject options (gh-6815)', function() {
     const mongoose = new Mongoose();
 
     mongoose.set('toObject', { virtuals: true });
@@ -259,10 +245,9 @@ describe('mongoose module:', function() {
     const doc = new M();
     assert.equal(doc.toObject().foo, 42);
     assert.strictEqual(doc.toJSON().foo, void 0);
-    done();
   });
 
-  it('strict option (gh-6858)', function(done) {
+  it('strict option (gh-6858)', function() {
     const mongoose = new Mongoose();
 
     // With strict: throw, no schema-level override
@@ -301,8 +286,6 @@ describe('mongoose module:', function() {
     assert.strictEqual(doc.$__.strictMode, false);
 
     assert.equal(doc.toObject().bar, 'baz');
-
-    done();
   });
 
   it('declaring global plugins (gh-5690)', function(done) {
@@ -437,7 +420,7 @@ describe('mongoose module:', function() {
     return Promise.resolve();
   });
 
-  it('top-level ObjectId, Decimal128, Mixed (gh-6760)', function(done) {
+  it('top-level ObjectId, Decimal128, Mixed (gh-6760)', function() {
     const mongoose = new Mongoose();
 
     const schema = new Schema({
@@ -452,8 +435,6 @@ describe('mongoose module:', function() {
 
     assert.ok(doc.testId instanceof mongoose.Types.ObjectId);
     assert.ok(doc.testNum instanceof mongoose.Types.Decimal128);
-
-    done();
   });
 
   it('stubbing now() for timestamps (gh-6728)', function() {
@@ -582,7 +563,7 @@ describe('mongoose module:', function() {
   });
 
   describe('model()', function() {
-    it('accessing a model that hasn\'t been defined', function(done) {
+    it('accessing a model that hasn\'t been defined', function() {
       const mong = new Mongoose();
       let thrown = false;
 
@@ -594,7 +575,6 @@ describe('mongoose module:', function() {
       }
 
       assert.equal(thrown, true);
-      done();
     });
 
     it('returns the model at creation', function(done) {

From be9f2db2a8841f2e79e5af780a4df02614b60457 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 15 May 2020 06:01:05 +0200
Subject: [PATCH 0863/2348] test: refactor more tests re #8999

---
 test/index.test.js               | 17 +++++-----------
 test/model.aggregate.test.js     |  6 ++----
 test/model.discriminator.test.js | 34 --------------------------------
 3 files changed, 7 insertions(+), 50 deletions(-)

diff --git a/test/index.test.js b/test/index.test.js
index da4df5de6c4..5d4c85e6c51 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -577,7 +577,7 @@ describe('mongoose module:', function() {
       assert.equal(thrown, true);
     });
 
-    it('returns the model at creation', function(done) {
+    it('returns the model at creation', function() {
       const Named = mongoose.model('Named', new Schema({ name: String }));
       const n1 = new Named();
       assert.equal(n1.name, null);
@@ -588,7 +588,6 @@ describe('mongoose module:', function() {
       const Numbered = mongoose.model('Numbered', schema, collection);
       const n3 = new Numbered({ number: 1234 });
       assert.equal(n3.number.valueOf(), 1234);
-      done();
     });
 
     it('prevents overwriting pre-existing models', function(done) {
@@ -616,7 +615,7 @@ describe('mongoose module:', function() {
       done();
     });
 
-    it('allows passing identical name+schema+collection args (gh-5767)', function(done) {
+    it('allows passing identical name+schema+collection args (gh-5767)', function() {
       const m = new Mongoose;
       const schema = new Schema;
       const model = m.model('A', schema, 'AA');
@@ -626,16 +625,12 @@ describe('mongoose module:', function() {
       });
 
       assert.equal(model, m.model('A', model.schema, 'AA'));
-
-      done();
     });
 
-    it('throws on unknown model name', function(done) {
+    it('throws on unknown model name', function() {
       assert.throws(function() {
         mongoose.model('iDoNotExist!');
       }, /Schema hasn't been registered/);
-
-      done();
     });
 
     describe('passing collection name', function() {
@@ -734,14 +729,12 @@ describe('mongoose module:', function() {
       assert.equal(typeof mongoose.Error.VersionError, 'function');
     }
 
-    it('of module', function(done) {
+    it('of module', function() {
       test(mongoose);
-      done();
     });
 
-    it('of new Mongoose instances', function(done) {
+    it('of new Mongoose instances', function() {
       test(new mongoose.Mongoose);
-      done();
     });
 
     it('of result from .connect() (gh-3940)', function(done) {
diff --git a/test/model.aggregate.test.js b/test/model.aggregate.test.js
index 98dc7b1b239..d9c8a576db0 100644
--- a/test/model.aggregate.test.js
+++ b/test/model.aggregate.test.js
@@ -114,14 +114,12 @@ describe('model aggregate', function() {
       });
     });
 
-    it('when returning Aggregate', function(done) {
+    it('when returning Aggregate', function() {
       assert(A.aggregate([project]) instanceof Aggregate);
-      done();
     });
 
-    it('throws when passing object (gh-6732)', function(done) {
+    it('throws when passing object (gh-6732)', function() {
       assert.throws(() => A.aggregate({}), /disallows passing a spread/);
-      done();
     });
 
     it('can use helper for $out', function(done) {
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 1c8ba262794..6db4fe4612d 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -90,7 +90,6 @@ describe('model', function() {
     it('model defaults without discriminator', function(done) {
       var Model = db.model('Test1', new Schema());
       assert.equal(Model.discriminators, undefined);
-      done();
     });
 
     it('is instance of root', function(done) {
@@ -100,7 +99,6 @@ describe('model', function() {
       assert.ok(employee instanceof Employee);
       assert.strictEqual(employee.__proto__.constructor, Employee);
       assert.strictEqual(employee.__proto__.__proto__.constructor, Person);
-      done();
     });
 
     it('can define static and instance methods', function(done) {
@@ -131,24 +129,20 @@ describe('model', function() {
       assert.equal(boss.notInstanceMethod, undefined);
       assert.equal(Boss.currentPresident(), 'obama');
       assert.equal(Boss.notStaticMethod, undefined);
-      done();
     });
 
     it('sets schema root discriminator mapping', function(done) {
       assert.deepEqual(Person.schema.discriminatorMapping, {key: '__t', value: null, isRoot: true});
-      done();
     });
 
     it('sets schema discriminator type mapping', function(done) {
       assert.deepEqual(Employee.schema.discriminatorMapping, {key: '__t', value: 'Employee', isRoot: false});
-      done();
     });
 
     it('adds discriminatorKey to schema with default as name', function(done) {
       var type = Employee.schema.paths.__t;
       assert.equal(type.options.type, String);
       assert.equal(type.options.default, 'Employee');
-      done();
     });
 
     it('adds discriminator to Model.discriminators object', function(done) {
@@ -158,7 +152,6 @@ describe('model', function() {
       var NewDiscriminatorType = Person.discriminator(newName, new Schema());
       assert.equal(Object.keys(Person.discriminators).length, 2);
       assert.equal(Person.discriminators[newName], NewDiscriminatorType);
-      done();
     });
 
     it('throws error on invalid schema', function(done) {
@@ -168,7 +161,6 @@ describe('model', function() {
           },
           /You must pass a valid discriminator Schema/
       );
-      done();
     });
 
     it('throws error when attempting to nest discriminators', function(done) {
@@ -178,7 +170,6 @@ describe('model', function() {
           },
           /Discriminator "model-discriminator-foo" can only be a discriminator of the root model/
       );
-      done();
     });
 
     it('throws error when discriminator has mapped discriminator key in schema', function(done) {
@@ -188,7 +179,6 @@ describe('model', function() {
           },
           /Discriminator "model-discriminator-foo" cannot have field with name "__t"/
       );
-      done();
     });
 
     it('throws error when discriminator has mapped discriminator key in schema with discriminatorKey option set', function(done) {
@@ -199,7 +189,6 @@ describe('model', function() {
           },
           /Discriminator "Bar" cannot have field with name "_type"/
       );
-      done();
     });
 
     it('throws error when discriminator with taken name is added', function(done) {
@@ -211,7 +200,6 @@ describe('model', function() {
           },
           /Discriminator with name "Token" already exists/
       );
-      done();
     });
 
     it('throws error if model name is taken (gh-4148)', function(done) {
@@ -222,7 +210,6 @@ describe('model', function() {
           Foo.discriminator('Test', new Schema());
         },
         /Cannot overwrite `Test`/);
-      done();
     });
 
     it('works with nested schemas (gh-2821)', function(done) {
@@ -255,20 +242,17 @@ describe('model', function() {
         var Person = db.model('Test1', PersonSchema);
         Person.discriminator('Boss', BossSchema);
       });
-      done();
     });
 
     describe('options', function() {
       it('allows toObject to be overridden', function(done) {
         assert.notDeepEqual(Employee.schema.get('toObject'), Person.schema.get('toObject'));
         assert.deepEqual(Employee.schema.get('toObject'), {getters: true, virtuals: false});
-        done();
       });
 
       it('allows toJSON to be overridden', function(done) {
         assert.notDeepEqual(Employee.schema.get('toJSON'), Person.schema.get('toJSON'));
         assert.deepEqual(Employee.schema.get('toJSON'), {getters: false, virtuals: true});
-        done();
       });
 
       it('is not customizable', function(done) {
@@ -277,8 +261,6 @@ describe('model', function() {
         assert.throws(function() {
           Person.discriminator('model-discriminator-custom', CustomizedSchema);
         }, /Can't customize discriminator option capped/);
-
-        done();
       });
     });
 
@@ -287,13 +269,11 @@ describe('model', function() {
         assert.strictEqual(Employee.schema.path('name'), Person.schema.path('name'));
         assert.strictEqual(Employee.schema.path('gender'), Person.schema.path('gender'));
         assert.equal(Person.schema.paths.department, undefined);
-        done();
       });
 
       it('inherits validators', function(done) {
         assert.strictEqual(Employee.schema.path('gender').validators, PersonSchema.path('gender').validators);
         assert.strictEqual(Employee.schema.path('department').validators, EmployeeSchema.path('department').validators);
-        done();
       });
 
       it('does not inherit and override fields that exist', function(done) {
@@ -305,7 +285,6 @@ describe('model', function() {
         assert.notStrictEqual(gender, Person.schema.paths.gender);
         assert.equal(gender.instance, 'String');
         assert.equal(gender.options.default, 'F');
-        done();
       });
 
       it('inherits methods', function(done) {
@@ -313,27 +292,23 @@ describe('model', function() {
         assert.strictEqual(employee.getFullName, PersonSchema.methods.getFullName);
         assert.strictEqual(employee.getDepartment, EmployeeSchema.methods.getDepartment);
         assert.equal((new Person).getDepartment, undefined);
-        done();
       });
 
       it('inherits statics', function(done) {
         assert.strictEqual(Employee.findByGender, PersonSchema.statics.findByGender);
         assert.strictEqual(Employee.findByDepartment, EmployeeSchema.statics.findByDepartment);
         assert.equal(Person.findByDepartment, undefined);
-        done();
       });
 
       it('inherits virtual (g.s)etters', function(done) {
         var employee = new Employee();
         employee.name.full = 'John Doe';
         assert.equal(employee.name.full, 'John Doe');
-        done();
       });
 
       it('does not inherit indexes', function(done) {
         assert.deepEqual(Person.schema.indexes(), [[{name: 1}, {background: true}]]);
         assert.deepEqual(Employee.schema.indexes(), [[{department: 1}, {background: true}]]);
-        done();
       });
 
       it('gets options overridden by root options except toJSON and toObject', function(done) {
@@ -346,7 +321,6 @@ describe('model', function() {
         delete employeeOptions.toObject;
 
         assert.deepEqual(personOptions, employeeOptions);
-        done();
       });
 
       it('does not allow setting discriminator key (gh-2041)', function(done) {
@@ -398,7 +372,6 @@ describe('model', function() {
         Model.discriminator('D', new Schema({
           test2: String
         }, { typeKey: '$type' }));
-        done();
       });
 
       describe('applyPluginsToDiscriminators', function() {
@@ -421,8 +394,6 @@ describe('model', function() {
           });
           Model.discriminator('D', childSchema);
           assert.equal(called, 2);
-  
-          done();
         });
 
         it('works with customized options (gh-7458)', function() {
@@ -618,7 +589,6 @@ describe('model', function() {
         assert.doesNotThrow(function () {
          Person.discriminator('Parent2', parentSchema.clone());
         });
-        done();
       });
 
       it('clone() allows reusing with different models (gh-5721)', function(done) {
@@ -726,8 +696,6 @@ describe('model', function() {
         assert.equal(doc1.stuff[0].name, 'test');
         assert.equal(doc2.things.length, 1);
         assert.equal(doc2.things[0].name, 'test');
-
-        done();
       });
 
       it('overwrites nested paths in parent schema (gh-6076)', function(done) {
@@ -759,8 +727,6 @@ describe('model', function() {
         });
 
         assert.ifError(d1.validateSync());
-
-        done();
       });
 
       it('nested discriminator key with projecting in parent (gh-5775)', function(done) {

From e9c826cc1769bffe13b6a07a8ea1388555b3179a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 15 May 2020 07:16:33 +0200
Subject: [PATCH 0864/2348] docs(document): elaborate on how Document#save
 works re #9001

---
 lib/document.js | 3 ++-
 lib/model.js    | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index dce56008b3d..f59a1bb617e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2606,7 +2606,8 @@ Document.prototype.$markValid = function(path) {
 };
 
 /**
- * Saves this document.
+ * Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`,
+ * or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation **only** with the modifications to the database, it does not replace the whole document in the latter case.
  *
  * ####Example:
  *
diff --git a/lib/model.js b/lib/model.js
index cc9a7851232..784cfeb3683 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -415,7 +415,8 @@ function generateVersionError(doc, modifiedPaths) {
 }
 
 /**
- * Saves this document.
+ * Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`,
+ * or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation **only** with the modifications to the database, it does not replace the whole document in the latter case.
  *
  * ####Example:
  *

From cea1b267083e3346eaf3a676bb21815cea83bc9b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 15 May 2020 07:27:48 +0200
Subject: [PATCH 0865/2348] docs(faq): remove slow-localhost

---
 docs/faq.pug | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index 8f64ebf8e60..825199c95b6 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -429,19 +429,6 @@ block content
     **A**. Technically, any 12 character string is a valid [ObjectId](https://docs.mongodb.com/manual/reference/bson-types/#objectid).
     Consider using a regex like `/^[a-f0-9]{24}$/` to test whether a string is exactly 24 hex characters.
 
-    <hr id="slow-localhost" />
-
-    <a href="#slow-localhost">**Q**</a>. I'm connecting to `localhost` and it takes me nearly 1 second to connect. How do I fix this?
-
-    **A**. The underlying MongoDB driver defaults to looking for IPv6 addresses, so the most likely cause is that your `localhost` DNS mapping isn't configured to handle IPv6. Use `127.0.0.1` instead of `localhost` or use the `family` option as shown in the [connection docs](https://mongoosejs.com/docs/connections.html#options).
-
-    ```javascript
-    // One alternative is to bypass 'localhost'
-    mongoose.connect('mongodb://127.0.0.1:27017/test');
-    // Another option is to specify the `family` option, which tells the
-    // MongoDB driver to only look for IPv4 addresses rather than IPv6 first.
-    mongoose.connect('mongodb://localhost:27017/test', { family: 4 });
-    ```
 
     <hr id="map-keys-strings" />
 

From d0674d9fb5bc35e80dc5271720ed8601007bdefc Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 15 May 2020 07:28:09 +0200
Subject: [PATCH 0866/2348] style: add empty lines before each question

---
 docs/faq.pug | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/docs/faq.pug b/docs/faq.pug
index 825199c95b6..59f08721765 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -30,6 +30,7 @@ block content
       <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
     </div>
 
+
     <hr id="array-changes-not-saved" />
 
     <a href="#array-changes-not-saved">**Q**</a>. Why don't my changes to arrays get saved when I update an element
@@ -72,6 +73,7 @@ block content
     doc.save();
     ```
 
+
     <hr id="unique-doesnt-work" />
 
     <a href="#unique-doesnt-work">**Q**</a>. I declared a schema property as `unique` but I can still save
@@ -124,6 +126,7 @@ block content
     rather than relying on mongoose to do it for you. The `unique` option for schemas is
     convenient for development and documentation, but mongoose is *not* an index management solution.
 
+
     <hr id="nested-properties" />
 
     <a href="#nested-properties">**Q**</a>. When I have a nested property in a schema, mongoose adds empty objects by default. Why?
@@ -154,6 +157,7 @@ block content
     must always be defined as an object on a mongoose document, even if `nested`
     is undefined on the underlying [POJO](./guide.html#minimize).
 
+
     <hr id="destructured-imports" />
 
     <a href="#destructured-imports">**Q**</a>. When I use named imports like `import { set } from 'mongoose'`, I
@@ -179,6 +183,7 @@ block content
     foo(); // "undefined"
     ```
 
+
     <hr id="arrow-functions" />
 
     <a href="#arrow-functions">**Q**</a>. I'm using an arrow function for a [virtual](./guide.html#virtuals), [middleware](./middleware.html), [getter](./api.html#schematype_SchemaType-get)/[setter](./api.html#schematype_SchemaType-set), or [method](./guide.html#methods) and the value of `this` is wrong.
@@ -209,6 +214,7 @@ block content
     });
     ```
 
+
     <hr id="type-key">
 
     <a href="#type-key">**Q**</a>. I have an embedded property named `type` like this:
@@ -253,6 +259,7 @@ block content
     });
     ```
 
+
     <hr id="populate_sort_order" />
 
     <a href="#populate_sort_order">**Q**</a>. I'm populating a nested property under an array like the below code:
@@ -278,6 +285,7 @@ block content
     connect to MongoDB. Read the [buffering section of the connection docs](./connections.html#buffering)
     for more information.
 
+
     <hr id="enable_debugging" />
 
     <a href="#enable_debugging">**Q**</a>. How can I enable debugging?
@@ -294,6 +302,7 @@ block content
     All executed collection methods will log output of their arguments to your
     console.
 
+
     <hr id="callback_never_executes" />
 
     <a href="#callback_never_executes">**Q**</a>. My `save()` callback never executes. What am I doing wrong?
@@ -319,6 +328,7 @@ block content
     mongoose.set('bufferCommands', false);
     ```
 
+
     <hr id="creating_connections" />
 
     <a href="#creating_connections">**Q**</a>. Should I create/destroy a new connection for each database operation?
@@ -326,6 +336,7 @@ block content
     **A**. No. Open your connection when your application starts up and leave
     it open until the application shuts down.
 
+
     <hr id="overwrite-model-error" />
 
     <a href="#overwrite-model-error">**Q**</a>. Why do I get "OverwriteModelError: Cannot overwrite .. model once
@@ -351,6 +362,7 @@ block content
     var Kitten = connection.model('Kitten', kittySchema);
     ```
 
+
     <hr id="array-defaults" />
 
     <a href="#array-defaults">**Q**</a>. How can I change mongoose's default behavior of initializing an array
@@ -365,6 +377,8 @@ block content
       }
     });
     ```
+
+
     <hr id="initialize-array-path-null" />
     
     <a href="#initialize-array-path-null">**Q**</a>. How can I initialize an array path to `null`?
@@ -389,6 +403,7 @@ block content
     to query by date using the aggregation framework, you're responsible for ensuring
     that you're passing in a valid date.
 
+
     <hr id="date_changes" />
 
     <a href="#date_changes">**Q**</a>. Why don't in-place modifications to date objects
@@ -445,6 +460,7 @@ block content
     [perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in
     mind that populate() will execute a separate query for each document.
 
+
     <hr id="add_something" />
 
     **Something to add?**

From e50f8996b8c3e6765aa75d7de5a30d6f649401cb Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Thu, 14 May 2020 23:24:40 -0700
Subject: [PATCH 0867/2348] Fix typos in documents.pug

---
 docs/documents.pug | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/documents.pug b/docs/documents.pug
index a6534660981..a2ddd4e3bed 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -71,7 +71,7 @@ block content
     ```javascript
     doc.name = 'foo';
 
-    // Mongoose sends a `updateOne({ _id: doc._id }, { $set: { name: 'foo' } })`
+    // Mongoose sends an `updateOne({ _id: doc._id }, { $set: { name: 'foo' } })`
     // to MongoDB.
     await doc.save();
     ```
@@ -108,7 +108,7 @@ block content
 
     ### Validating
 
-    Documents are casted validated before they are saved. Mongoose first casts
+    Documents are casted and validated before they are saved. Mongoose first casts
     values to the specified type and then validates them. Internally, Mongoose
     calls the document's [`validate()` method](api.html#document_Document-validate)
     before saving.

From 8227492a89e0b77b79c1a3160bb6c14da2abc133 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 15 May 2020 14:00:51 +0200
Subject: [PATCH 0868/2348] docs(schematype): add note about throwing error
 only after validation

---
 docs/schematypes.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 7c7ac9edcdb..4647df77420 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -348,7 +348,7 @@ block content
     The values `null` and `undefined` are not cast.
 
     NaN, strings that cast to NaN, arrays, and objects that don't have a `valueOf()` function
-    will all result in a [CastError](/docs/api.html#mongooseerror_MongooseError.CastError).
+    will all result in a [CastError](/docs/api.html#mongooseerror_MongooseError.CastError) once validated, meaning that it will not throw on initialization, only when validated.
 
     <h4 id="dates">Dates</h4>
 

From df45db84e2a1411d5ef2bc89042721b5062662fa Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 15 May 2020 14:01:58 +0200
Subject: [PATCH 0869/2348] docs(schematypes): fix broken reference to
 api/CastError

---
 docs/schematypes.pug | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 4647df77420..6984ec12e09 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -348,7 +348,7 @@ block content
     The values `null` and `undefined` are not cast.
 
     NaN, strings that cast to NaN, arrays, and objects that don't have a `valueOf()` function
-    will all result in a [CastError](/docs/api.html#mongooseerror_MongooseError.CastError) once validated, meaning that it will not throw on initialization, only when validated.
+    will all result in a [CastError](/docs/validation.html#cast-errors) once validated, meaning that it will not throw on initialization, only when validated.
 
     <h4 id="dates">Dates</h4>
 
@@ -472,7 +472,7 @@ block content
     * `'0'`
     * `'no'`
 
-    Any other value causes a [CastError](/docs/api.html#mongooseerror_MongooseError.CastError).
+    Any other value causes a [CastError](/docs/validation.html#cast-errors).
     You can modify what values Mongoose converts to true or false using the
     `convertToTrue` and `convertToFalse` properties, which are [JavaScript sets](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set).
 

From dcacea6d8b298a4041c10b4448c71e0ca250c633 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 15 May 2020 16:54:49 -0400
Subject: [PATCH 0870/2348] fix(schema): remove `db` from reserved keywords

Fix #8940
---
 lib/schema.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 777cfce4434..1a43160b7bc 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -538,7 +538,6 @@ Schema.prototype.add = function add(obj, prefix) {
  * - _posts
  * - _pres
  * - collection
- * - db
  * - emit
  * - errors
  * - get
@@ -576,7 +575,6 @@ reserved.on =
 reserved.removeListener =
 // document properties and functions
 reserved.collection =
-reserved.db =
 reserved.errors =
 reserved.get =
 reserved.init =

From d5fa450e9899abe7cb80fb4f0d20c21d74aa9812 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 15 May 2020 17:01:31 -0400
Subject: [PATCH 0871/2348] test: fix tests re: #8940

---
 test/schema.test.js | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 0a1e00f6b80..5289baad65b 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1436,12 +1436,6 @@ describe('schema', function() {
         });
       }, /`schema` may not be used as a schema pathname/);
 
-      assert.throws(function() {
-        new Schema({
-          db: String
-        });
-      }, /`db` may not be used as a schema pathname/);
-
       assert.throws(function() {
         new Schema({
           isNew: String
@@ -2413,21 +2407,21 @@ describe('schema', function() {
 
   describe('Schema.reserved (gh-8869)', function() {
     it('throws errors on compiling schema with reserved key as a flat type', function() {
-      const buildInvalidSchema = () => new Schema({ db: String });
+      const buildInvalidSchema = () => new Schema({ save: String });
 
-      assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
+      assert.throws(buildInvalidSchema, /`save` may not be used as a schema pathname/);
     });
 
     it('throws errors on compiling schema with reserved key as a nested object', function() {
-      const buildInvalidSchema = () => new Schema({ db: { nested: String } });
+      const buildInvalidSchema = () => new Schema({ save: { nested: String } });
 
-      assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
+      assert.throws(buildInvalidSchema, /`save` may not be used as a schema pathname/);
     });
 
     it('throws errors on compiling schema with reserved key as a nested array', function() {
-      const buildInvalidSchema = () => new Schema({ db: [{ nested: String }] });
+      const buildInvalidSchema = () => new Schema({ save: [{ nested: String }] });
 
-      assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
+      assert.throws(buildInvalidSchema, /`save` may not be used as a schema pathname/);
     });
   });
 });

From 108e126a35722ec792bfd4fa011fc8d3e2d7d890 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 15 May 2020 18:27:28 -0400
Subject: [PATCH 0872/2348] fix(populate): treat populating a doc array that
 doesn't have a `ref` as a no-op

Fix #8946
---
 .../populate/getModelsMapForPopulate.js       |  8 +++++
 lib/model.js                                  |  8 +++++
 test/model.populate.test.js                   | 30 +++++++++++++++++++
 3 files changed, 46 insertions(+)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index d6b51c397d3..4853921cf69 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -42,6 +42,14 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     doc = docs[i];
 
     schema = getSchemaTypes(modelSchema, doc, options.path);
+    // Special case: populating a path that's a DocumentArray unless
+    // there's an explicit `ref` or `refPath` re: gh-8946
+    if (schema != null &&
+        schema.$isMongooseDocumentArray &&
+        schema.options.ref == null &&
+        schema.options.refPath == null) {
+      continue;
+    }
     const isUnderneathDocArray = schema && schema.$isUnderneathDocArray;
     if (isUnderneathDocArray && get(options, 'options.sort') != null) {
       return new MongooseError('Cannot populate with `sort` on path ' + options.path +
diff --git a/lib/model.js b/lib/model.js
index bdaf9af1959..8aa9792f37f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4444,6 +4444,14 @@ function populate(model, docs, options, callback) {
   }
 
   if (!hasOne) {
+    // If no models to populate but we have a nested populate,
+    // keep trying, re: gh-8946
+    if (options.populate != null) {
+      const opts = options.populate.map(pop => Object.assign({}, pop, {
+        path: options.path + '.' + pop.path
+      }));
+      return model.populate(docs, opts, callback);
+    }
     return callback();
   }
 
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 3772214004b..5d268e0ce43 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9378,4 +9378,34 @@ describe('model: populate:', function() {
       });
     });
   });
+
+  it('no-op if populating on a document array with no ref (gh-8946)', function() {
+    const teamSchema = Schema({
+      members: [{ user: { type: ObjectId, ref: 'User' } }]
+    });
+    const userSchema = Schema({ name: { type: String } });
+    userSchema.virtual('teams', {
+      ref: 'Team',
+      localField: '_id',
+      foreignField: 'members.user',
+      justOne: false
+    });
+    const User = db.model('User', userSchema);
+    const Team = db.model('Team', teamSchema);
+
+    return co(function*() {
+      const user = yield User.create({ name: 'User' });
+      yield Team.create({ members: [{ user: user._id }] });
+
+      const res = yield User.findOne().populate({
+        path: 'teams',
+        populate: {
+          path: 'members', // No ref
+          populate: { path: 'user' }
+        }
+      });
+
+      assert.equal(res.teams[0].members[0].user.name, 'User');
+    });
+  });
 });

From 71cc8f2ec564e14f4160fd2de7c5b1709d1f1f43 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 15 May 2020 18:41:50 -0400
Subject: [PATCH 0873/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 1a329a34019..9c7f16501d3 100644
--- a/index.pug
+++ b/index.pug
@@ -343,6 +343,9 @@ html(lang='en')
               <a href="https://casinohex.co.za/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-co-za/470843d/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.casinofever.ca/">
+                <img class="sponsor" src="https://images.opencollective.com/casinofever-ca1/4ad150e/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 1b190b63f6067e950a385b900e94d7ad0ec2b3d6 Mon Sep 17 00:00:00 2001
From: Jeremy Philippe <jeremy.philippe@gmail.com>
Date: Sat, 16 May 2020 12:32:30 +0200
Subject: [PATCH 0874/2348] fix(documentarray): make sure you can call
 `unshift()` after `map()`

Fix #9012
---
 lib/types/core_array.js          | 12 +++++++++---
 test/types.documentarray.test.js | 21 +++++++++++++++++++++
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index b6632359daa..c4c6b33b441 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -879,7 +879,7 @@ class CoreMongooseArray extends Array {
    *
    * ####Note:
    *
-   * _marks the entire array as modified, which if saved, will store it as a `$set` operation, potentially overwritting any changes that happen between when you retrieved the object and when you save it._
+   * _marks the entire array as modified, which if saved, will store it as a `$set` operation, potentially overwriting any changes that happen between when you retrieved the object and when you save it._
    *
    * @api public
    * @method unshift
@@ -889,8 +889,14 @@ class CoreMongooseArray extends Array {
   unshift() {
     _checkManualPopulation(this, arguments);
 
-    let values = [].map.call(arguments, this._cast, this);
-    values = this[arraySchemaSymbol].applySetters(values, this[arrayParentSymbol]);
+    let values;
+    if (this[arraySchemaSymbol] == null) {
+      values = arguments;
+    } else {
+      values = [].map.call(arguments, this._cast, this);
+      values = this[arraySchemaSymbol].applySetters(values, this[arrayParentSymbol]);
+    }
+
     [].unshift.apply(this, values);
     this._registerAtomic('$set', this);
     this._markModified();
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 22d9db368a9..93bafeccaa8 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -611,6 +611,27 @@ describe('types.documentarray', function() {
         'd'
       ]);
     });
+
+    it('unshift() after map() works (gh-9012)', function() {
+      const MyModel = db.model('Test', Schema({
+        myArray: [{ name: String }]
+      }));
+
+      const doc = new MyModel({
+        myArray: [{ name: 'b' }, { name: 'c' }]
+      });
+      let myArray = doc.myArray;
+
+      myArray = myArray.map(val => ({ name: `${val.name} mapped` }));
+
+      myArray.unshift({ name: 'a inserted' });
+
+      assert.deepEqual(myArray.map(v => v.name), [
+        'a inserted',
+        'b mapped',
+        'c mapped'
+      ]);
+    });
   });
 
   it('cleans modified subpaths on splice() (gh-7249)', function() {

From 2fd29b0339710a1ec7f91b5fa5f83b9e28d105e1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 16 May 2020 13:38:40 +0200
Subject: [PATCH 0875/2348] docs: add anchor tag to strictQuery

---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 442496d09cc..42a21890aed 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -739,7 +739,7 @@ block content
     thing.save(); // iAmNotInTheSchema is never saved to the db
     ```
 
-    <h3 id="strictQuery">option: strictQuery</h3>
+    <h3 id="strictQuery"><a href="#strictQuery">option: strictQuery</a></h3>
 
     For backwards compatibility, the `strict` option does **not** apply to
     the `filter` parameter for queries.

From 5da9f44837124534903a0b68e53c4a497936219a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 16 May 2020 14:18:11 +0200
Subject: [PATCH 0876/2348] test: repro #6658 strictQuery

---
 test/schema.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 0a1e00f6b80..fa45ee07f90 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2430,4 +2430,26 @@ describe('schema', function() {
       assert.throws(buildInvalidSchema, /`db` may not be used as a schema pathname/);
     });
   });
+
+  it('setting `strictQuery` on base sets strictQuery to schema', function() {
+    // Arrange
+    mongoose.set('strictQuery', 'some value');
+
+    // Act
+    const schema = new Schema();
+
+    // Assert
+    assert.equal(schema.get('strictQuery'), 'some value');
+  });
+
+  it('`strictQuery` set on base gets overwritten by option set on schema', function() {
+    // Arrange
+    mongoose.set('strictQuery', 'base option');
+
+    // Act
+    const schema = new Schema({}, { strictQuery: 'schema option' });
+
+    // Assert
+    assert.equal(schema.get('strictQuery'), 'schema option');
+  });
 });

From f7f9b4fbe2980f444a5d7c3a5e03c27924f9afb8 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 16 May 2020 14:21:42 +0200
Subject: [PATCH 0877/2348] fix(base): allow setting strictQuery globally

---
 lib/index.js        | 1 +
 lib/schema.js       | 1 +
 lib/validoptions.js | 1 +
 3 files changed, 3 insertions(+)

diff --git a/lib/index.js b/lib/index.js
index 8c7c9f0aa90..30e51fd26f1 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -158,6 +158,7 @@ Mongoose.prototype.driver = require('./driver');
  * - 'toObject': `{ transform: true, flattenDecimals: true }` by default. Overwrites default objects to [`toObject()`](/docs/api.html#document_Document-toObject)
  * - 'toJSON': `{ transform: true, flattenDecimals: true }` by default. Overwrites default objects to [`toJSON()`](/docs/api.html#document_Document-toJSON), for determining how Mongoose documents get serialized by `JSON.stringify()`
  * - 'strict': true by default, may be `false`, `true`, or `'throw'`. Sets the default strict mode for schemas.
+ * - 'strictQuery': false by default, may be `false`, `true`, or `'throw'`. Sets the default [strictQuery](/docs/guide.html#strictQuery) mode for schemas.
  * - 'selectPopulatedPaths': true by default. Set to false to opt out of Mongoose adding all fields that you `populate()` to your `select()`. The schema-level option `selectPopulatedPaths` overwrites this one.
  * - 'typePojoToMixed': true by default, may be `false` or `true`. Sets the default typePojoToMixed for schemas.
  * - 'maxTimeMS': If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query
diff --git a/lib/schema.js b/lib/schema.js
index 777cfce4434..996fd04f023 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -400,6 +400,7 @@ Schema.prototype.defaultOptions = function(options) {
   const baseOptions = get(this, 'base.options', {});
   options = utils.options({
     strict: 'strict' in baseOptions ? baseOptions.strict : true,
+    strictQuery: 'strictQuery' in baseOptions ? baseOptions.strictQuery : false,
     bufferCommands: true,
     capped: false, // { size, max, autoIndexId }
     versionKey: '__v',
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 9464e4d8611..68a7b424dfd 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -17,6 +17,7 @@ const VALID_OPTIONS = Object.freeze([
   'runValidators',
   'selectPopulatedPaths',
   'strict',
+  'strictQuery',
   'toJSON',
   'toObject',
   'useCreateIndex',

From 80d40e557645f9cca1ec54fd09283efde52acb6d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 16 May 2020 14:42:16 +0200
Subject: [PATCH 0878/2348] fix test causing other tests to fail

---
 test/schema.test.js | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index fa45ee07f90..43b3e14d431 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2431,8 +2431,9 @@ describe('schema', function() {
     });
   });
 
-  it('setting `strictQuery` on base sets strictQuery to schema', function() {
+  it('setting `strictQuery` on base sets strictQuery to schema (gh-6658)', function() {
     // Arrange
+    const originalValue = mongoose.get('strictQuery');
     mongoose.set('strictQuery', 'some value');
 
     // Act
@@ -2440,10 +2441,14 @@ describe('schema', function() {
 
     // Assert
     assert.equal(schema.get('strictQuery'), 'some value');
+
+    // Cleanup
+    mongoose.set('strictQuery', originalValue);
   });
 
-  it('`strictQuery` set on base gets overwritten by option set on schema', function() {
+  it('`strictQuery` set on base gets overwritten by option set on schema (gh-6658)', function() {
     // Arrange
+    const originalValue = mongoose.get('strictQuery');
     mongoose.set('strictQuery', 'base option');
 
     // Act
@@ -2451,5 +2456,8 @@ describe('schema', function() {
 
     // Assert
     assert.equal(schema.get('strictQuery'), 'schema option');
+
+    // Cleanup
+    mongoose.set('strictQuery', originalValue);
   });
 });

From 93b3ed6dbc2c8ec2a113b9db9bc19dd9d105422b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 16 May 2020 14:50:16 +0200
Subject: [PATCH 0879/2348] test: refactor tests re #6658, use beforeEach to
 guard against failed tests not cleaning up after failing which will in turn
 cause more tests to fail, making it difficult to know the root cause of all
 the failing tests

---
 test/schema.test.js | 41 ++++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 21 deletions(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 43b3e14d431..88dca91175d 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2431,33 +2431,32 @@ describe('schema', function() {
     });
   });
 
-  it('setting `strictQuery` on base sets strictQuery to schema (gh-6658)', function() {
-    // Arrange
-    const originalValue = mongoose.get('strictQuery');
-    mongoose.set('strictQuery', 'some value');
+  describe('mongoose.set(`strictQuery`, value); (gh-6658)', function() {
+    let strictQueryOriginalValue;
 
-    // Act
-    const schema = new Schema();
+    this.beforeEach(() => strictQueryOriginalValue = mongoose.get('strictQuery'));
+    this.afterEach(() => mongoose.set('strictQuery', strictQueryOriginalValue));
 
-    // Assert
-    assert.equal(schema.get('strictQuery'), 'some value');
+    it('setting `strictQuery` on base sets strictQuery to schema (gh-6658)', function() {
+      // Arrange
+      mongoose.set('strictQuery', 'some value');
 
-    // Cleanup
-    mongoose.set('strictQuery', originalValue);
-  });
+      // Act
+      const schema = new Schema();
 
-  it('`strictQuery` set on base gets overwritten by option set on schema (gh-6658)', function() {
-    // Arrange
-    const originalValue = mongoose.get('strictQuery');
-    mongoose.set('strictQuery', 'base option');
+      // Assert
+      assert.equal(schema.get('strictQuery'), 'some value');
+    });
 
-    // Act
-    const schema = new Schema({}, { strictQuery: 'schema option' });
+    it('`strictQuery` set on base gets overwritten by option set on schema (gh-6658)', function() {
+      // Arrange
+      mongoose.set('strictQuery', 'base option');
 
-    // Assert
-    assert.equal(schema.get('strictQuery'), 'schema option');
+      // Act
+      const schema = new Schema({}, { strictQuery: 'schema option' });
 
-    // Cleanup
-    mongoose.set('strictQuery', originalValue);
+      // Assert
+      assert.equal(schema.get('strictQuery'), 'schema option');
+    });
   });
 });

From 3c46473c6d8a0fdc5265bba6750d03353479ccf1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 16 May 2020 15:17:16 +0200
Subject: [PATCH 0880/2348] docs(guide): add anchor tag to strict option

---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 42a21890aed..e71cfefe32d 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -688,7 +688,7 @@ block content
     _Note that Mongoose does not send the `shardcollection` command for you. You
     must configure your shards yourself._
 
-    <h3 id="strict">option: strict</h3>
+    <h3 id="strict"><a href="#strict">option: strict</a></h3>
 
     The strict option, (enabled by default), ensures that values passed to our
     model constructor that were not specified in our schema do not get saved to

From 3d19ec18945f103260cab8b9a92c393e0f0d19fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 14:15:20 -0400
Subject: [PATCH 0881/2348] test(timestamps): repro #8894

---
 test/timestamps.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index 5d28fabb92b..4142a169144 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -337,4 +337,31 @@ describe('timestamps', function() {
     });
   });
 
+  it('sets timestamps on deeply nested docs on upsert (gh-8894)', function() {
+    const JournalSchema = Schema({ message: String }, { timestamps: true });
+    const ProductSchema = Schema({
+      name: String,
+      journal: [JournalSchema],
+      lastJournal: JournalSchema
+    }, { timestamps: true });
+    const schema = Schema({ products: [ProductSchema] }, { timestamps: true });
+    const Order = db.model('Order', schema);
+  
+    const update = {
+      products: [{
+        name: 'ASUS Vivobook Pro',
+        journal: [{ message: 'out of stock' }],
+        lastJournal: { message: 'out of stock' }
+      }]
+    };
+
+    return Order.findOneAndUpdate({}, update, { upsert: true, new: true }).
+      then(doc => {
+        assert.ok(doc.products[0].journal[0].createdAt);
+        assert.ok(doc.products[0].journal[0].updatedAt);
+
+        assert.ok(doc.products[0].lastJournal.createdAt);
+        assert.ok(doc.products[0].lastJournal.updatedAt);
+      });
+  });
 });

From 6197c74c7ea2c4f21c8ac9135d9a8f58d52b492d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 14:15:36 -0400
Subject: [PATCH 0882/2348] fix(timestamps): set createdAt and updatedAt on
 doubly nested subdocs when upserting

Fix #8894
---
 lib/helpers/update/applyTimestampsToChildren.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 1b376170ab7..7e9edd881eb 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -165,6 +165,8 @@ function applyTimestampsToDocumentArray(arr, schematype, now) {
     if (createdAt != null) {
       arr[i][createdAt] = now;
     }
+
+    applyTimestampsToChildren(now, arr[i], schematype.schema);
   }
 }
 
@@ -182,4 +184,6 @@ function applyTimestampsToSingleNested(subdoc, schematype, now) {
   if (createdAt != null) {
     subdoc[createdAt] = now;
   }
+
+  applyTimestampsToChildren(now, subdoc, schematype.schema);
 }

From 9c172e967a725aaa95de35ca005a6810660bd29f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 14:18:11 -0400
Subject: [PATCH 0883/2348] style: fix lint

---
 test/timestamps.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index 4142a169144..dedb2dccb19 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -346,7 +346,7 @@ describe('timestamps', function() {
     }, { timestamps: true });
     const schema = Schema({ products: [ProductSchema] }, { timestamps: true });
     const Order = db.model('Order', schema);
-  
+
     const update = {
       products: [{
         name: 'ASUS Vivobook Pro',

From c7dec6305ed56886565bf2f8bce00d793a02e7e0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 15:05:24 -0400
Subject: [PATCH 0884/2348] test(schema): repro #9020

---
 test/schema.test.js | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 5289baad65b..b01d5f7d248 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1196,7 +1196,7 @@ describe('schema', function() {
   });
 
   describe('#add()', function() {
-    it('does not polute existing paths', function(done) {
+    it('does not pollute existing paths', function(done) {
       let o = { name: String };
       let s = new Schema(o);
 
@@ -2424,4 +2424,13 @@ describe('schema', function() {
       assert.throws(buildInvalidSchema, /`save` may not be used as a schema pathname/);
     });
   });
+
+  it('treats dotted paths with no parent as a nested path (gh-9020)', function() {
+    const customerSchema = new Schema({
+      'card.brand': String,
+      'card.last4': String
+    });
+
+    assert.ok(customerSchema.nested['card']);
+  });
 });

From 59f00246ac990ccbab193cd8fb92761c651d712d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 15:05:46 -0400
Subject: [PATCH 0885/2348] fix(schema): treat creating dotted path with no
 parent as creating a nested path

Fix #9020
---
 lib/schema.js | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 1a43160b7bc..062b5be8321 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -656,21 +656,24 @@ Schema.prototype.path = function(path, obj) {
   const subpaths = path.split(/\./);
   const last = subpaths.pop();
   let branch = this.tree;
+  let fullPath = '';
 
-  subpaths.forEach(function(sub, i) {
+  for (const sub of subpaths) {
+    fullPath = fullPath += (fullPath.length > 0 ? '.' : '') + sub;
     if (!branch[sub]) {
+      this.nested[fullPath] = true;
       branch[sub] = {};
     }
     if (typeof branch[sub] !== 'object') {
       const msg = 'Cannot set nested path `' + path + '`. '
           + 'Parent path `'
-          + subpaths.slice(0, i).concat([sub]).join('.')
+          + fullPath
           + '` already set to type ' + branch[sub].name
           + '.';
       throw new Error(msg);
     }
     branch = branch[sub];
-  });
+  }
 
   branch[last] = utils.clone(obj);
 

From a262140b37a91df1089ef007d2ff3dbaf0c757c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 18:13:14 -0400
Subject: [PATCH 0886/2348] feat(connection): add `transaction()` function to
 handle resetting `Document#isNew` when a transaction is aborted

Fix #8852
---
 lib/connection.js               | 53 +++++++++++++++++++++++++++++++++
 lib/helpers/symbols.js          |  1 +
 lib/index.js                    |  4 ++-
 lib/plugins/trackTransaction.js | 20 +++++++++++++
 test/docs/transactions.test.js  | 21 ++++++++++++-
 5 files changed, 97 insertions(+), 2 deletions(-)
 create mode 100644 lib/plugins/trackTransaction.js

diff --git a/lib/connection.js b/lib/connection.js
index 12f0517aa06..85a00c27bcb 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -22,6 +22,8 @@ const utils = require('./utils');
 
 const parseConnectionString = require('mongodb/lib/core').parseConnectionString;
 
+const sessionNewDocuments = require('./helpers/symbols').sessionNewDocuments;
+
 let id = 0;
 
 /*!
@@ -417,6 +419,57 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
   cb(null, session);
 });
 
+/**
+ * _Requires MongoDB >= 3.6.0._ Executes the wrapped async function
+ * in a transaction. Mongoose will commit the transaction if the
+ * async function executes successfully and attempt to retry if
+ * there was a retriable error.
+ * 
+ * Calls the MongoDB driver's [`session.withTransaction()`](http://mongodb.github.io/node-mongodb-native/3.5/api/ClientSession.html#withTransaction),
+ * but also handles resetting Mongoose document state as shown below.
+ *
+ * ####Example:
+ *
+ *     const doc = new Person({ name: 'Will Riker' });
+ *     await db.transaction(async function setRank(session) {
+ *       doc.rank = 'Captain';
+ *       await doc.save({ session });
+ *       doc.isNew; // false
+ * 
+ *       // Throw an error to abort the transaction
+ *       throw new Error('Oops!');
+ *     }).catch(() => {});
+ *
+ *     // true, `transaction()` reset the document's state because the
+ *     // transaction was aborted.
+ *     doc.isNew;
+ *
+ * @method transaction
+ * @param {Function} fn Function to execute in a transaction
+ * @return {Promise<Any>} promise that resolves to the returned value of `fn`
+ * @api public
+ */
+
+Connection.prototype.transaction = function transaction(fn) {
+  return this.startSession().then(session => {
+    session[sessionNewDocuments] = [];
+    return session.withTransaction(() => fn(session)).
+      then(res => {
+        delete session[sessionNewDocuments];
+        return res;
+      }).
+      catch(err => {
+        // If transaction was aborted, we need to reset newly
+        // inserted documents' `isNew`.
+        for (const doc of session[sessionNewDocuments]) {
+          doc.isNew = true;
+        }
+        delete session[sessionNewDocuments];
+        throw err;
+      });
+  });
+};
+
 /**
  * Helper for `dropCollection()`. Will delete the given collection, including
  * all documents and indexes.
diff --git a/lib/helpers/symbols.js b/lib/helpers/symbols.js
index 3860f237743..4db388edfe7 100644
--- a/lib/helpers/symbols.js
+++ b/lib/helpers/symbols.js
@@ -11,4 +11,5 @@ exports.modelSymbol = Symbol('mongoose#Model');
 exports.objectIdSymbol = Symbol('mongoose#ObjectId');
 exports.populateModelSymbol = Symbol('mongoose.PopulateOptions#Model');
 exports.schemaTypeSymbol = Symbol('mongoose#schemaType');
+exports.sessionNewDocuments = Symbol('mongoose:ClientSession#newDocuments');
 exports.validatorErrorSymbol = Symbol('mongoose:validatorError');
\ No newline at end of file
diff --git a/lib/index.js b/lib/index.js
index 8c7c9f0aa90..b0d3e086151 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -34,6 +34,7 @@ const pkg = require('../package.json');
 const cast = require('./cast');
 const removeSubdocs = require('./plugins/removeSubdocs');
 const saveSubdocs = require('./plugins/saveSubdocs');
+const trackTransaction = require('./plugins/trackTransaction');
 const validateBeforeSave = require('./plugins/validateBeforeSave');
 
 const Aggregate = require('./aggregate');
@@ -106,7 +107,8 @@ function Mongoose(options) {
       [saveSubdocs, { deduplicate: true }],
       [validateBeforeSave, { deduplicate: true }],
       [shardingPlugin, { deduplicate: true }],
-      [removeSubdocs, { deduplicate: true }]
+      [removeSubdocs, { deduplicate: true }],
+      [trackTransaction, { deduplicate: true }]
     ]
   });
 }
diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
new file mode 100644
index 00000000000..c307f9b759a
--- /dev/null
+++ b/lib/plugins/trackTransaction.js
@@ -0,0 +1,20 @@
+'use strict';
+
+const sessionNewDocuments = require('../helpers/symbols').sessionNewDocuments;
+
+module.exports = function trackTransaction(schema) {
+  schema.pre('save', function() {
+    if (!this.isNew) {
+      return;
+    }
+
+    const session = this.$session();
+    if (session == null) {
+      return;
+    }
+    if (session.transaction == null || session[sessionNewDocuments] == null) {
+      return;
+    }
+    session[sessionNewDocuments].push(this);
+  });
+};
\ No newline at end of file
diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index e27662861d8..73daab51e83 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -360,7 +360,26 @@ describe('transactions', function() {
         const test = yield Test.create([{}], { session }).then(res => res[0]);
         yield test.save(); // throws DocumentNotFoundError
       }));
-      yield session.endSession();
+      session.endSession();
+    });
+  });
+
+  it('correct `isNew` after abort (gh-8852)', function() {
+    return co(function*() {
+      const schema = Schema({ name: String });
+
+      const Test = db.model('gh8852', schema);
+
+      yield Test.createCollection();
+      const doc = new Test({ name: 'foo' });
+      yield db.
+        transaction(session => co(function*() {
+          yield doc.save({ session });
+          assert.ok(!doc.isNew);
+          throw new Error('Oops');
+        })).
+        catch(err => assert.equal(err.message, 'Oops'));
+      assert.ok(doc.isNew);
     });
   });
 });

From eab6cc07858762cade92fa64e64e635557d69f6a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 16 May 2020 18:17:57 -0400
Subject: [PATCH 0887/2348] style: fix lint

---
 lib/connection.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 85a00c27bcb..d9dabf5b04e 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -424,7 +424,7 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
  * in a transaction. Mongoose will commit the transaction if the
  * async function executes successfully and attempt to retry if
  * there was a retriable error.
- * 
+ *
  * Calls the MongoDB driver's [`session.withTransaction()`](http://mongodb.github.io/node-mongodb-native/3.5/api/ClientSession.html#withTransaction),
  * but also handles resetting Mongoose document state as shown below.
  *
@@ -435,7 +435,7 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
  *       doc.rank = 'Captain';
  *       await doc.save({ session });
  *       doc.isNew; // false
- * 
+ *
  *       // Throw an error to abort the transaction
  *       throw new Error('Oops!');
  *     }).catch(() => {});

From 478f84197c10fe75fe6afa664df88212f140c3a3 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Sun, 17 May 2020 03:48:51 -0700
Subject: [PATCH 0888/2348] update returns updateWriteOpResult

---
 lib/model.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index d7a6feda7ab..74b9c6d44a7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3636,8 +3636,8 @@ Model.hydrate = function(obj) {
  * @see response http://docs.mongodb.org/v2.6/reference/command/update/#output
  * @param {Object} filter
  * @param {Object} doc
- * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {Object} [options] optional see [`Query.prototype.setOptions()`](/api.html#query_Query-setOptions)
+ * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
@@ -3646,11 +3646,11 @@ Model.hydrate = function(obj) {
  * @param {Boolean} [options.setDefaultsOnInsert=false] if this and `upsert` are true, mongoose will apply the [defaults](http://mongoosejs.com/docs/defaults.html) specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on [MongoDB's `$setOnInsert` operator](https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/).
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `doc`, Mongoose will wrap `doc` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`.
- * @param {Function} [callback] params are (error, writeOpResult)
+ * @param {Function} [callback] params are (error, [updateWriteOpResult](https://mongodb.github.io/node-mongodb-native/3.6/api/Collection.html#~updateWriteOpResult))
  * @param {Function} [callback]
  * @return {Query}
  * @see MongoDB docs https://docs.mongodb.com/manual/reference/command/update/#update-command-output
- * @see writeOpResult http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~WriteOpResult
+ * @see writeOpResult https://mongodb.github.io/node-mongodb-native/3.6/api/Collection.html#~updateWriteOpResult
  * @see Query docs https://mongoosejs.com/docs/queries.html
  * @api public
  */

From 28d005fd90ee329051f8e6dc85e9ff726a967d3d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 17 May 2020 18:14:08 +0200
Subject: [PATCH 0889/2348] docs(index): fix typo

Fix typo, /^fluff/ starts with a lowercase letter.
---
 docs/index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/index.pug b/docs/index.pug
index 656c4db626f..53ee6aca26c 100644
--- a/docs/index.pug
+++ b/docs/index.pug
@@ -125,7 +125,7 @@ block content
     ```
 
     This performs a search for all documents with a name property that begins
-    with "Fluff" and returns the result as an array of kittens to the callback.
+    with "fluff" and returns the result as an array of kittens to the callback.
 
     ### Congratulations
 

From e736a738a2047f7a0ce85dfd098aa33642648eaa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 17 May 2020 17:19:41 -0400
Subject: [PATCH 0890/2348] test(model): repro #8938

---
 test/model.test.js | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 52ad90d9252..56081f17db3 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4528,6 +4528,37 @@ describe('Model', function() {
       }
     });
 
+    it('insertMany() `writeErrors` if only one error (gh-8938)', function() {
+      const QuestionType = new mongoose.Schema({
+        code: { type: String, required: true, unique: true },
+        text: String
+      });
+      const Question = db.model('Test', QuestionType);
+
+      return co(function*() {
+        yield Question.init();
+
+        yield Question.create({ code: 'MEDIUM', text: '123' });
+        const data = [
+          { code: 'MEDIUM', text: '1111' },
+          { code: 'test', text: '222' },
+          { code: 'HARD', text: '2222' }
+        ];
+        const opts = { ordered: false, rawResult: true };
+        let err = yield Question.insertMany(data, opts).catch(err => err);
+        assert.ok(Array.isArray(err.writeErrors));
+        assert.equal(err.writeErrors.length, 1);
+
+        yield Question.deleteMany({});
+        yield Question.create({ code: 'MEDIUM', text: '123' });
+        yield Question.create({ code: 'HARD', text: '123' });
+
+        err = yield Question.insertMany(data, opts).catch(err => err);
+        assert.ok(Array.isArray(err.writeErrors));
+        assert.equal(err.writeErrors.length, 2);
+      });
+    });
+
     it('insertMany() ordered option for single validation error', function(done) {
       start.mongodVersion(function(err, version) {
         if (err) {

From faaff4494a67874ec7be8e1f3d9b7d172318647d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 17 May 2020 17:19:57 -0400
Subject: [PATCH 0891/2348] fix(model): ensure consistent `writeErrors`
 property on insertMany error with `ordered: false`, even if only one op
 failed

Re: #8938
---
 lib/model.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index d7a6feda7ab..901228e2120 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3381,6 +3381,10 @@ Model.$__insertMany = function(arr, options, callback) {
 
     _this.collection.insertMany(docObjects, options, function(error, res) {
       if (error) {
+        if (error.writeErrors == null &&
+            get(error, 'result.result.writeErrors') != null) {
+          error.writeErrors = error.result.result.writeErrors;
+        }
         callback(error, null);
         return;
       }

From b5c52117841edfe956656a4ed62d1d7b39d771ef Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 17 May 2020 17:33:14 -0400
Subject: [PATCH 0892/2348] fix(model): report `insertedDocs` on `insertMany()`
 errors

Fix #8938
---
 lib/model.js       | 9 +++++++++
 test/model.test.js | 5 +++++
 2 files changed, 14 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index 901228e2120..73d38045073 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3381,10 +3381,19 @@ Model.$__insertMany = function(arr, options, callback) {
 
     _this.collection.insertMany(docObjects, options, function(error, res) {
       if (error) {
+        // `writeErrors` is a property reported by the MongoDB driver,
+        // just not if there's only 1 error.
         if (error.writeErrors == null &&
             get(error, 'result.result.writeErrors') != null) {
           error.writeErrors = error.result.result.writeErrors;
         }
+
+        // `insertedDocs` is a Mongoose-specific property
+        const erroredIndexes = new Set(error.writeErrors.map(err => err.index));
+        error.insertedDocs = docAttributes.filter((doc, i) => {
+          return !erroredIndexes.has(i);
+        });
+
         callback(error, null);
         return;
       }
diff --git a/test/model.test.js b/test/model.test.js
index 56081f17db3..3c59e5afb73 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4548,6 +4548,9 @@ describe('Model', function() {
         let err = yield Question.insertMany(data, opts).catch(err => err);
         assert.ok(Array.isArray(err.writeErrors));
         assert.equal(err.writeErrors.length, 1);
+        assert.equal(err.insertedDocs.length, 2);
+        assert.equal(err.insertedDocs[0].code, 'test');
+        assert.equal(err.insertedDocs[1].code, 'HARD');
 
         yield Question.deleteMany({});
         yield Question.create({ code: 'MEDIUM', text: '123' });
@@ -4556,6 +4559,8 @@ describe('Model', function() {
         err = yield Question.insertMany(data, opts).catch(err => err);
         assert.ok(Array.isArray(err.writeErrors));
         assert.equal(err.writeErrors.length, 2);
+        assert.equal(err.insertedDocs.length, 1);
+        assert.equal(err.insertedDocs[0].code, 'test');
       });
     });
 

From 12aa3b36515cc372ec213831e5ab9b2e7b24df6f Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Mon, 18 May 2020 04:32:27 -0700
Subject: [PATCH 0893/2348] docs: fix `/docs/` omission from path

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 74b9c6d44a7..d83675d3a97 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3636,7 +3636,7 @@ Model.hydrate = function(obj) {
  * @see response http://docs.mongodb.org/v2.6/reference/command/update/#output
  * @param {Object} filter
  * @param {Object} doc
- * @param {Object} [options] optional see [`Query.prototype.setOptions()`](/api.html#query_Query-setOptions)
+ * @param {Object} [options] optional see [`Query.prototype.setOptions()`](/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object} [options.writeConcern=null] sets the [write concern](https://docs.mongodb.com/manual/reference/write-concern/) for replica sets. Overrides the [schema-level write concern](/docs/guide.html#writeConcern)

From dba19fb0e4a001c3a2b1104f0f46f01a3045beaa Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Mon, 18 May 2020 04:35:53 -0700
Subject: [PATCH 0894/2348] docs: model.findByIdAndUpdate() 'new' param fix

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 73d38045073..550522e9706 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2622,7 +2622,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Object|Number|String} id value of `_id` to query by
  * @param {Object} [update]
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Boolean} [options.new=false] By default, `findByIdAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)

From 8ac42aa79daa3915dfe887b9b6256f362bd377d2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 May 2020 18:41:53 -0400
Subject: [PATCH 0895/2348] chore: release 5.9.15

---
 History.md   | 16 ++++++++++++++++
 package.json |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index eed6cc667b1..068fece6ef0 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,19 @@
+5.9.15 / 2020-05-18
+===================
+ * fix(schema): treat creating dotted path with no parent as creating a nested path #9020
+ * fix(documentarray): make sure you can call `unshift()` after `map()` #9012 [philippejer](https://github.com/philippejer)
+ * fix(model): cast bulkwrite according to discriminator schema if discriminator key is present #8982 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(schema): remove `db` from reserved keywords #8940
+ * fix(populate): treat populating a doc array that doesn't have a `ref` as a no-op #8946
+ * fix(timestamps): set createdAt and updatedAt on doubly nested subdocs when upserting #8894
+ * fix(model): allow POJOs as schemas for model.discriminator(...) #8991 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(model): report `insertedDocs` on `insertMany()` errors #8938
+ * fix(model): ensure consistent `writeErrors` property on insertMany error with `ordered: false`, even if only one op failed #8938
+ * docs: add anchor tag to strictQuery and strict #9014 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(faq): remove faq ipv6 #9004
+ * docs: add note about throwing error only after validation and fix broken reference to api/CastError #8993 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: fix typos in documents.pug #9005 [dandv](https://github.com/dandv)
+
 5.9.14 / 2020-05-13
 ===================
  * fix(cursor): add index as second parameter to eachAsync callback #8972 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 62aab6f6b91..2830a991e0a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.14",
+  "version": "5.9.15",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 44c270c43815deaec3dfd925c3117ed0ff950ce9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 May 2020 18:48:22 -0400
Subject: [PATCH 0896/2348] chore: update opencollective sponsors

---
 index.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.pug b/index.pug
index 9c7f16501d3..47fb9de2f81 100644
--- a/index.pug
+++ b/index.pug
@@ -343,9 +343,15 @@ html(lang='en')
               <a href="https://casinohex.co.za/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-co-za/470843d/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://uk.edubirdie.com/">
+                <img class="sponsor" src="https://images.opencollective.com/uk-edubirdie-com/b1d51ab/logo/256.png" style="height: 100px">
+              </a>
               <a href="https://www.casinofever.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinofever-ca1/4ad150e/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.parhaatnettikasinot.com/">
+                <img class="sponsor" src="https://images.opencollective.com/parhaatnettikasinot-com/fc53017/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From ffb1f847d9c3b8052c56dc73cac3fb84bd38f843 Mon Sep 17 00:00:00 2001
From: Zach Bjornson <zbbjornson@gmail.com>
Date: Sat, 16 May 2020 16:07:59 -0600
Subject: [PATCH 0897/2348] refactor(error): convert errors to classes
 extending Error

---
 lib/error/browserMissingSchema.js |  30 +++-----
 lib/error/cast.js                 | 123 +++++++++++++++---------------
 lib/error/disconnected.js         |  33 +++-----
 lib/error/divergentArray.js       |  49 +++++-------
 lib/error/missingSchema.js        |  33 +++-----
 lib/error/mongooseError.js        |  22 ++----
 lib/error/notFound.js             |  63 +++++++--------
 lib/error/objectExpected.js       |  40 ++++------
 lib/error/objectParameter.js      |  40 ++++------
 lib/error/overwriteModel.js       |  28 +++----
 lib/error/parallelSave.js         |  31 ++++----
 lib/error/parallelValidate.js     |  30 ++++----
 lib/error/serverSelection.js      |  65 +++++++---------
 lib/error/strict.js               |  44 +++++------
 lib/error/validation.js           |  95 +++++++++++------------
 lib/error/validator.js            |  76 +++++++++---------
 lib/error/version.js              |  38 ++++-----
 17 files changed, 361 insertions(+), 479 deletions(-)

diff --git a/lib/error/browserMissingSchema.js b/lib/error/browserMissingSchema.js
index 852f8739bc3..fe492d53ccc 100644
--- a/lib/error/browserMissingSchema.js
+++ b/lib/error/browserMissingSchema.js
@@ -6,30 +6,20 @@
 
 const MongooseError = require('./');
 
-/*!
- * MissingSchema Error constructor.
- *
- * @inherits MongooseError
- */
 
-function MissingSchemaError() {
-  const msg = 'Schema hasn\'t been registered for document.\n'
-          + 'Use mongoose.Document(name, schema)';
-  MongooseError.call(this, msg);
-  this.name = 'MissingSchemaError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class MissingSchemaError extends MongooseError {
+  /*!
+   * MissingSchema Error constructor.
+   */
+  constructor() {
+    super('Schema hasn\'t been registered for document.\n'
+      + 'Use mongoose.Document(name, schema)');
   }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-MissingSchemaError.prototype = Object.create(MongooseError.prototype);
-MissingSchemaError.prototype.constructor = MongooseError;
+Object.defineProperty(MissingSchemaError.prototype, 'name', {
+  value: 'MongooseError'
+});
 
 /*!
  * exports
diff --git a/lib/error/cast.js b/lib/error/cast.js
index 671931718e8..c6ff277086c 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -17,98 +17,101 @@ const util = require('util');
  * @api private
  */
 
-function CastError(type, value, path, reason, schemaType) {
-  // If no args, assume we'll `init()` later.
-  if (arguments.length > 0) {
-    this.init(type, value, path, reason, schemaType);
+class CastError extends MongooseError {
+  constructor(type, value, path, reason, schemaType) {
+    // If no args, assume we'll `init()` later.
+    if (arguments.length > 0) {
+      const stringValue = getStringValue(value);
+      const messageFormat = getMessageFormat(schemaType);
+      const msg = formatMessage(null, type, stringValue, path, messageFormat);
+      super(msg);
+      this.init(type, value, path, reason, schemaType);
+    } else {
+      super(formatMessage());
+    }
   }
 
-  MongooseError.call(this, this.formatMessage());
-  this.name = 'CastError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+  /*!
+   * ignore
+   */
+  init(type, value, path, reason, schemaType) {
+    this.stringValue = getStringValue(value);
+    this.messageFormat = getMessageFormat(schemaType);
+    this.kind = type;
+    this.value = value;
+    this.path = path;
+    this.reason = reason;
   }
-}
 
-/*!
- * Inherits from MongooseError.
- */
+  /*!
+   * ignore
+   * @param {Readonly<CastError>} other
+   */
+  copy(other) {
+    this.messageFormat = other.messageFormat;
+    this.stringValue = other.stringValue;
+    this.kind = other.kind;
+    this.value = other.value;
+    this.path = other.path;
+    this.reason = other.reason;
+    this.message = other.message;
+  }
 
-CastError.prototype = Object.create(MongooseError.prototype);
-CastError.prototype.constructor = MongooseError;
+  /*!
+   * ignore
+   */
+  setModel(model) {
+    this.model = model;
+    this.message = formatMessage(model, this.kind, this.stringValue, this.path,
+      this.messageFormat);
+  }
+}
 
-/*!
- * ignore
- */
+Object.defineProperty(CastError.prototype, 'name', {
+  value: 'CastError'
+});
 
-CastError.prototype.init = function init(type, value, path, reason, schemaType) {
+function getStringValue(value) {
   let stringValue = util.inspect(value);
-  stringValue = stringValue.replace(/^'/, '"').replace(/'$/, '"');
+  stringValue = stringValue.replace(/^'|'$/g, '"');
   if (!stringValue.startsWith('"')) {
     stringValue = '"' + stringValue + '"';
   }
+  return stringValue;
+}
 
+function getMessageFormat(schemaType) {
   const messageFormat = get(schemaType, 'options.cast', null);
   if (typeof messageFormat === 'string') {
-    this.messageFormat = schemaType.options.cast;
+    return messageFormat;
   }
-  this.stringValue = stringValue;
-  this.kind = type;
-  this.value = value;
-  this.path = path;
-  this.reason = reason;
-};
-
-/*!
- * ignore
- */
-
-CastError.prototype.copy = function copy(other) {
-  this.messageFormat = other.messageFormat;
-  this.stringValue = other.stringValue;
-  this.kind = other.kind;
-  this.value = other.value;
-  this.path = other.path;
-  this.reason = other.reason;
-  this.message = other.message;
-};
-
-/*!
- * ignore
- */
-
-CastError.prototype.setModel = function(model) {
-  this.model = model;
-  this.message = this.formatMessage(model);
-};
+}
 
 /*!
  * ignore
  */
 
-CastError.prototype.formatMessage = function(model) {
-  if (this.messageFormat != null) {
-    let ret = this.messageFormat.
-      replace('{KIND}', this.kind).
-      replace('{VALUE}', this.stringValue).
-      replace('{PATH}', this.path);
+function formatMessage(model, kind, stringValue, path, messageFormat) {
+  if (messageFormat != null) {
+    let ret = messageFormat.
+      replace('{KIND}', kind).
+      replace('{VALUE}', stringValue).
+      replace('{PATH}', path);
     if (model != null) {
       ret = ret.replace('{MODEL}', model.modelName);
     }
 
     return ret;
   } else {
-    let ret = 'Cast to ' + this.kind + ' failed for value ' +
-      this.stringValue + ' at path "' + this.path + '"';
+    let ret = 'Cast to ' + kind + ' failed for value ' +
+      stringValue + ' at path "' + path + '"';
     if (model != null) {
       ret += ' for model "' + model.modelName + '"';
     }
 
     return ret;
   }
-};
+}
 
 /*!
  * exports
diff --git a/lib/error/disconnected.js b/lib/error/disconnected.js
index 3e36c1cc981..777a1def270 100644
--- a/lib/error/disconnected.js
+++ b/lib/error/disconnected.js
@@ -6,35 +6,26 @@
 
 const MongooseError = require('./');
 
+
 /**
  * The connection failed to reconnect and will never successfully reconnect to
  * MongoDB without manual intervention.
- *
- * @param {String} type
- * @param {String} value
- * @inherits MongooseError
  * @api private
  */
-
-function DisconnectedError(connectionString) {
-  MongooseError.call(this, 'Ran out of retries trying to reconnect to "' +
-    connectionString + '". Try setting `server.reconnectTries` and ' +
-    '`server.reconnectInterval` to something higher.');
-  this.name = 'DisconnectedError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class DisconnectedError extends MongooseError {
+  /**
+   * @param {String} connectionString
+   */
+  constructor(connectionString) {
+    super('Ran out of retries trying to reconnect to "' +
+      connectionString + '". Try setting `server.reconnectTries` and ' +
+      '`server.reconnectInterval` to something higher.');
   }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-DisconnectedError.prototype = Object.create(MongooseError.prototype);
-DisconnectedError.prototype.constructor = MongooseError;
-
+Object.defineProperty(DisconnectedError.prototype, 'name', {
+  value: 'DisconnectedError'
+});
 
 /*!
  * exports
diff --git a/lib/error/divergentArray.js b/lib/error/divergentArray.js
index 872fd2bfac4..ed86caf1731 100644
--- a/lib/error/divergentArray.js
+++ b/lib/error/divergentArray.js
@@ -7,39 +7,28 @@
 
 const MongooseError = require('./');
 
-/*!
- * DivergentArrayError constructor.
- *
- * @inherits MongooseError
- */
-
-function DivergentArrayError(paths) {
-  const msg = 'For your own good, using `document.save()` to update an array '
-          + 'which was selected using an $elemMatch projection OR '
-          + 'populated using skip, limit, query conditions, or exclusion of '
-          + 'the _id field when the operation results in a $pop or $set of '
-          + 'the entire array is not supported. The following '
-          + 'path(s) would have been modified unsafely:\n'
-          + '  ' + paths.join('\n  ') + '\n'
-          + 'Use Model.update() to update these arrays instead.';
-  // TODO write up a docs page (FAQ) and link to it
-
-  MongooseError.call(this, msg);
-  this.name = 'DivergentArrayError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class DivergentArrayError extends MongooseError {
+  /*!
+   * DivergentArrayError constructor.
+   * @param {Array<String>} paths
+   */
+  constructor(paths) {
+    const msg = 'For your own good, using `document.save()` to update an array '
+            + 'which was selected using an $elemMatch projection OR '
+            + 'populated using skip, limit, query conditions, or exclusion of '
+            + 'the _id field when the operation results in a $pop or $set of '
+            + 'the entire array is not supported. The following '
+            + 'path(s) would have been modified unsafely:\n'
+            + '  ' + paths.join('\n  ') + '\n'
+            + 'Use Model.update() to update these arrays instead.';
+    // TODO write up a docs page (FAQ) and link to it
+    super(msg);
   }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-DivergentArrayError.prototype = Object.create(MongooseError.prototype);
-DivergentArrayError.prototype.constructor = MongooseError;
-
+Object.defineProperty(DivergentArrayError.prototype, 'name', {
+  value: 'DivergentArrayError'
+});
 
 /*!
  * exports
diff --git a/lib/error/missingSchema.js b/lib/error/missingSchema.js
index 319515820fb..ca306b7e611 100644
--- a/lib/error/missingSchema.js
+++ b/lib/error/missingSchema.js
@@ -7,30 +7,21 @@
 
 const MongooseError = require('./');
 
-/*!
- * MissingSchema Error constructor.
- *
- * @inherits MongooseError
- */
-
-function MissingSchemaError(name) {
-  const msg = 'Schema hasn\'t been registered for model "' + name + '".\n'
-          + 'Use mongoose.model(name, schema)';
-  MongooseError.call(this, msg);
-  this.name = 'MissingSchemaError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class MissingSchemaError extends MongooseError {
+  /*!
+   * MissingSchema Error constructor.
+   * @param {String} name
+   */
+  constructor(name) {
+    const msg = 'Schema hasn\'t been registered for model "' + name + '".\n'
+            + 'Use mongoose.model(name, schema)';
+    super(msg);
   }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-MissingSchemaError.prototype = Object.create(MongooseError.prototype);
-MissingSchemaError.prototype.constructor = MongooseError;
+Object.defineProperty(MissingSchemaError.prototype, 'name', {
+  value: 'MissingSchemaError'
+});
 
 /*!
  * exports
diff --git a/lib/error/mongooseError.js b/lib/error/mongooseError.js
index 2487dfed4b2..5505105cb6f 100644
--- a/lib/error/mongooseError.js
+++ b/lib/error/mongooseError.js
@@ -4,22 +4,10 @@
  * ignore
  */
 
-function MongooseError(msg) {
-  Error.call(this);
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
-  }
-  this.message = msg;
-  this.name = 'MongooseError';
-}
+class MongooseError extends Error { }
 
-/*!
- * Inherits from Error.
- */
-
-MongooseError.prototype = Object.create(Error.prototype);
-MongooseError.prototype.constructor = Error;
+Object.defineProperty(MongooseError.prototype, 'name', {
+  value: 'MongooseError'
+});
 
-module.exports = MongooseError;
\ No newline at end of file
+module.exports = MongooseError;
diff --git a/lib/error/notFound.js b/lib/error/notFound.js
index a12bcb25169..0e8386b8a25 100644
--- a/lib/error/notFound.js
+++ b/lib/error/notFound.js
@@ -7,46 +7,35 @@
 const MongooseError = require('./');
 const util = require('util');
 
-/*!
- * OverwriteModel Error constructor.
- *
- * @inherits MongooseError
- */
-
-function DocumentNotFoundError(filter, model, numAffected, result) {
-  let msg;
-  const messages = MongooseError.messages;
-  if (messages.DocumentNotFoundError != null) {
-    msg = typeof messages.DocumentNotFoundError === 'function' ?
-      messages.DocumentNotFoundError(filter, model) :
-      messages.DocumentNotFoundError;
-  } else {
-    msg = 'No document found for query "' + util.inspect(filter) +
-      '" on model "' + model + '"';
-  }
-
-  MongooseError.call(this, msg);
-
-  this.name = 'DocumentNotFoundError';
-  this.result = result;
-  this.numAffected = numAffected;
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class DocumentNotFoundError extends MongooseError {
+  /*!
+   * OverwriteModel Error constructor.
+   */
+  constructor(filter, model, numAffected, result) {
+    let msg;
+    const messages = MongooseError.messages;
+    if (messages.DocumentNotFoundError != null) {
+      msg = typeof messages.DocumentNotFoundError === 'function' ?
+        messages.DocumentNotFoundError(filter, model) :
+        messages.DocumentNotFoundError;
+    } else {
+      msg = 'No document found for query "' + util.inspect(filter) +
+        '" on model "' + model + '"';
+    }
+
+    super(msg);
+
+    this.result = result;
+    this.numAffected = numAffected;
+    this.filter = filter;
+    // Backwards compat
+    this.query = filter;
   }
-
-  this.filter = filter;
-  // Backwards compat
-  this.query = filter;
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-DocumentNotFoundError.prototype = Object.create(MongooseError.prototype);
-DocumentNotFoundError.prototype.constructor = MongooseError;
+Object.defineProperty(DocumentNotFoundError.prototype, 'name', {
+  value: 'DocumentNotFoundError'
+});
 
 /*!
  * exports
diff --git a/lib/error/objectExpected.js b/lib/error/objectExpected.js
index 9f9fac7f3bf..3b02bb4c296 100644
--- a/lib/error/objectExpected.js
+++ b/lib/error/objectExpected.js
@@ -6,33 +6,25 @@
 
 const MongooseError = require('./');
 
-/**
- * Strict mode error constructor
- *
- * @param {String} type
- * @param {String} value
- * @inherits MongooseError
- * @api private
- */
 
-function ObjectExpectedError(path, val) {
-  const typeDescription = Array.isArray(val) ? 'array' : 'primitive value';
-  MongooseError.call(this, 'Tried to set nested object field `' + path +
-    `\` to ${typeDescription} \`` + val + '` and strict mode is set to throw.');
-  this.name = 'ObjectExpectedError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class ObjectExpectedError extends MongooseError {
+  /**
+   * Strict mode error constructor
+   *
+   * @param {string} type
+   * @param {string} value
+   * @api private
+   */
+  constructor(path, val) {
+    const typeDescription = Array.isArray(val) ? 'array' : 'primitive value';
+    super('Tried to set nested object field `' + path +
+      `\` to ${typeDescription} \`` + val + '` and strict mode is set to throw.');
+    this.path = path;
   }
-  this.path = path;
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-ObjectExpectedError.prototype = Object.create(MongooseError.prototype);
-ObjectExpectedError.prototype.constructor = MongooseError;
+Object.defineProperty(ObjectExpectedError.prototype, 'name', {
+  value: 'ObjectExpectedError'
+});
 
 module.exports = ObjectExpectedError;
diff --git a/lib/error/objectParameter.js b/lib/error/objectParameter.js
index 3a7f2849cb8..5881a481aea 100644
--- a/lib/error/objectParameter.js
+++ b/lib/error/objectParameter.js
@@ -6,33 +6,25 @@
 
 const MongooseError = require('./');
 
-/**
- * Constructor for errors that happen when a parameter that's expected to be
- * an object isn't an object
- *
- * @param {Any} value
- * @param {String} paramName
- * @param {String} fnName
- * @inherits MongooseError
- * @api private
- */
-
-function ObjectParameterError(value, paramName, fnName) {
-  MongooseError.call(this, 'Parameter "' + paramName + '" to ' + fnName +
-    '() must be an object, got ' + value.toString());
-  this.name = 'ObjectParameterError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class ObjectParameterError extends MongooseError {
+  /**
+   * Constructor for errors that happen when a parameter that's expected to be
+   * an object isn't an object
+   *
+   * @param {Any} value
+   * @param {String} paramName
+   * @param {String} fnName
+   * @api private
+   */
+  constructor(value, paramName, fnName) {
+    super('Parameter "' + paramName + '" to ' + fnName +
+      '() must be an object, got ' + value.toString());
   }
 }
 
-/*!
- * Inherits from MongooseError.
- */
 
-ObjectParameterError.prototype = Object.create(MongooseError.prototype);
-ObjectParameterError.prototype.constructor = MongooseError;
+Object.defineProperty(ObjectParameterError.prototype, 'name', {
+  value: 'ObjectParameterError'
+});
 
 module.exports = ObjectParameterError;
diff --git a/lib/error/overwriteModel.js b/lib/error/overwriteModel.js
index 21013b65ec9..d509e19551e 100644
--- a/lib/error/overwriteModel.js
+++ b/lib/error/overwriteModel.js
@@ -7,28 +7,20 @@
 
 const MongooseError = require('./');
 
-/*!
- * OverwriteModel Error constructor.
- *
- * @inherits MongooseError
- */
 
-function OverwriteModelError(name) {
-  MongooseError.call(this, 'Cannot overwrite `' + name + '` model once compiled.');
-  this.name = 'OverwriteModelError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class OverwriteModelError extends MongooseError {
+  /*!
+   * OverwriteModel Error constructor.
+   * @param {String} name
+   */
+  constructor(name) {
+    super('Cannot overwrite `' + name + '` model once compiled.');
   }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-OverwriteModelError.prototype = Object.create(MongooseError.prototype);
-OverwriteModelError.prototype.constructor = MongooseError;
+Object.defineProperty(OverwriteModelError.prototype, 'name', {
+  value: 'OverwriteModelError'
+});
 
 /*!
  * exports
diff --git a/lib/error/parallelSave.js b/lib/error/parallelSave.js
index 1b546135582..e0628576de7 100644
--- a/lib/error/parallelSave.js
+++ b/lib/error/parallelSave.js
@@ -6,25 +6,22 @@
 
 const MongooseError = require('./');
 
-/**
- * ParallelSave Error constructor.
- *
- * @inherits MongooseError
- * @api private
- */
-
-function ParallelSaveError(doc) {
-  const msg = 'Can\'t save() the same doc multiple times in parallel. Document: ';
-  MongooseError.call(this, msg + doc._id);
-  this.name = 'ParallelSaveError';
+class ParallelSaveError extends MongooseError {
+  /**
+   * ParallelSave Error constructor.
+   *
+   * @param {Document} doc
+   * @api private
+   */
+  constructor(doc) {
+    const msg = 'Can\'t save() the same doc multiple times in parallel. Document: ';
+    super(msg + doc._id);
+  }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-ParallelSaveError.prototype = Object.create(MongooseError.prototype);
-ParallelSaveError.prototype.constructor = MongooseError;
+Object.defineProperty(ParallelSaveError.prototype, 'name', {
+  value: 'ParallelSaveError'
+});
 
 /*!
  * exports
diff --git a/lib/error/parallelValidate.js b/lib/error/parallelValidate.js
index c5cc83b89fa..18697b6bc91 100644
--- a/lib/error/parallelValidate.js
+++ b/lib/error/parallelValidate.js
@@ -6,25 +6,23 @@
 
 const MongooseError = require('./mongooseError');
 
-/**
- * ParallelValidate Error constructor.
- *
- * @inherits MongooseError
- * @api private
- */
 
-function ParallelValidateError(doc) {
-  const msg = 'Can\'t validate() the same doc multiple times in parallel. Document: ';
-  MongooseError.call(this, msg + doc._id);
-  this.name = 'ParallelValidateError';
+class ParallelValidateError extends MongooseError {
+  /**
+   * ParallelValidate Error constructor.
+   *
+   * @param {Document} doc
+   * @api private
+   */
+  constructor(doc) {
+    const msg = 'Can\'t validate() the same doc multiple times in parallel. Document: ';
+    super(msg + doc._id);
+  }
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-ParallelValidateError.prototype = Object.create(MongooseError.prototype);
-ParallelValidateError.prototype.constructor = MongooseError;
+Object.defineProperty(ParallelValidateError.prototype, 'name', {
+  value: 'ParallelValidateError'
+});
 
 /*!
  * exports
diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index 13f96b753f6..b5c755578d7 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -8,32 +8,6 @@ const MongooseError = require('./mongooseError');
 const allServersUnknown = require('../helpers/topology/allServersUnknown');
 const isAtlas = require('../helpers/topology/isAtlas');
 
-/**
- * MongooseServerSelectionError constructor
- *
- * @param {String} type
- * @param {String} value
- * @inherits MongooseError
- * @api private
- */
-
-function MongooseServerSelectionError(message) {
-  MongooseError.call(this, message);
-  this.name = 'MongooseServerSelectionError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
-  }
-}
-
-/*!
- * Inherits from MongooseError.
- */
-
-MongooseServerSelectionError.prototype = Object.create(MongooseError.prototype);
-MongooseServerSelectionError.prototype.constructor = MongooseError;
-
 /*!
  * ignore
  */
@@ -42,18 +16,31 @@ const atlasMessage = 'Could not connect to any servers in your MongoDB Atlas ' +
   'cluster. Make sure your current IP address is on your Atlas cluster\'s IP ' +
   'whitelist: https://docs.atlas.mongodb.com/security-whitelist/.';
 
-MongooseServerSelectionError.prototype.assimilateError = function(err) {
-  const reason = err.reason;
-  // Special message for a case that is likely due to IP whitelisting issues.
-  const isAtlasWhitelistError = isAtlas(reason) && allServersUnknown(reason);
-  this.message = isAtlasWhitelistError ?
-    atlasMessage :
-    err.message;
-  Object.assign(this, err, {
-    name: 'MongooseServerSelectionError'
-  });
-
-  return this;
-};
+class MongooseServerSelectionError extends MongooseError {
+  /**
+   * MongooseServerSelectionError constructor
+   *
+   * @api private
+   */
+  assimilateError(err) {
+    const reason = err.reason;
+    // Special message for a case that is likely due to IP whitelisting issues.
+    const isAtlasWhitelistError = isAtlas(reason) && allServersUnknown(reason);
+    this.message = isAtlasWhitelistError ?
+      atlasMessage :
+      err.message;
+    for (const key in err) {
+      if (key !== 'name') {
+        this[key] = err[key];
+      }
+    }
+
+    return this;
+  }
+}
+
+Object.defineProperty(MongooseServerSelectionError.prototype, 'name', {
+  value: 'MongooseServerSelectionError'
+});
 
 module.exports = MongooseServerSelectionError;
diff --git a/lib/error/strict.js b/lib/error/strict.js
index 7f32268ea4f..393ca6e1fc7 100644
--- a/lib/error/strict.js
+++ b/lib/error/strict.js
@@ -6,34 +6,28 @@
 
 const MongooseError = require('./');
 
-/**
- * Strict mode error constructor
- *
- * @param {String} type
- * @param {String} value
- * @inherits MongooseError
- * @api private
- */
 
-function StrictModeError(path, msg, immutable) {
-  msg = msg || 'Field `' + path + '` is not in schema and strict ' +
-    'mode is set to throw.';
-  MongooseError.call(this, msg);
-  this.name = 'StrictModeError';
-  this.isImmutableError = !!immutable;
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+class StrictModeError extends MongooseError {
+  /**
+   * Strict mode error constructor
+   *
+   * @param {String} path
+   * @param {String} [msg]
+   * @param {Boolean} [immutable]
+   * @inherits MongooseError
+   * @api private
+   */
+  constructor(path, msg, immutable) {
+    msg = msg || 'Field `' + path + '` is not in schema and strict ' +
+      'mode is set to throw.';
+    super(msg);
+    this.isImmutableError = !!immutable;
+    this.path = path;
   }
-  this.path = path;
 }
 
-/*!
- * Inherits from MongooseError.
- */
-
-StrictModeError.prototype = Object.create(MongooseError.prototype);
-StrictModeError.prototype.constructor = MongooseError;
+Object.defineProperty(StrictModeError.prototype, 'name', {
+  value: 'StrictModeError'
+});
 
 module.exports = StrictModeError;
diff --git a/lib/error/validation.js b/lib/error/validation.js
index ced82fc6957..9d4453762a5 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -7,59 +7,56 @@
 const MongooseError = require('./');
 const util = require('util');
 
-/**
- * Document Validation Error
- *
- * @api private
- * @param {Document} instance
- * @inherits MongooseError
- */
 
-function ValidationError(instance) {
-  this.errors = {};
-  this._message = '';
+class ValidationError extends MongooseError {
+  /**
+   * Document Validation Error
+   *
+   * @api private
+   * @param {Document} [instance]
+   * @inherits MongooseError
+   */
+  constructor(instance) {
+    let _message;
+    if (instance && instance.constructor.name === 'model') {
+      _message = instance.constructor.modelName + ' validation failed';
+    } else {
+      _message = 'Validation failed';
+    }
 
-  if (instance && instance.constructor.name === 'model') {
-    this._message = instance.constructor.modelName + ' validation failed';
-  } else {
-    this._message = 'Validation failed';
-  }
-  MongooseError.call(this, this._message);
-  this.name = 'ValidationError';
+    super(_message);
 
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
-  }
+    this.errors = {};
+    this._message = _message;
 
-  if (instance) {
-    instance.errors = this.errors;
+    if (instance) {
+      instance.errors = this.errors;
+    }
   }
-}
 
-/*!
- * Inherits from MongooseError.
- */
-
-ValidationError.prototype = Object.create(MongooseError.prototype);
-ValidationError.prototype.constructor = MongooseError;
-
-/**
- * Console.log helper
- */
+  /**
+   * Console.log helper
+   */
+  toString() {
+    return this.name + ': ' + _generateMessage(this);
+  }
 
-ValidationError.prototype.toString = function() {
-  return this.name + ': ' + _generateMessage(this);
-};
+  /*!
+   * inspect helper
+   */
+  inspect() {
+    return Object.assign(new Error(this.message), this);
+  }
 
-/*!
- * inspect helper
- */
+  /*!
+  * add message
+  */
+  addError(path, error) {
+    this.errors[path] = error;
+    this.message = this._message + ': ' + _generateMessage(this);
+  }
+}
 
-ValidationError.prototype.inspect = function() {
-  return Object.assign(new Error(this.message), this);
-};
 
 if (util.inspect.custom) {
   /*!
@@ -81,14 +78,10 @@ Object.defineProperty(ValidationError.prototype, 'toJSON', {
   }
 });
 
-/*!
- * add message
- */
 
-ValidationError.prototype.addError = function(path, error) {
-  this.errors[path] = error;
-  this.message = this._message + ': ' + _generateMessage(this);
-};
+Object.defineProperty(ValidationError.prototype, 'name', {
+  value: 'ValidationError'
+});
 
 /*!
  * ignore
diff --git a/lib/error/validator.js b/lib/error/validator.js
index 2464581faa3..8b06375d897 100644
--- a/lib/error/validator.js
+++ b/lib/error/validator.js
@@ -6,43 +6,44 @@
 
 const MongooseError = require('./');
 
-/**
- * Schema validator error
- *
- * @param {Object} properties
- * @inherits MongooseError
- * @api private
- */
 
-function ValidatorError(properties) {
-  let msg = properties.message;
-  if (!msg) {
-    msg = MongooseError.messages.general.default;
-  }
+class ValidatorError extends MongooseError {
+  /**
+   * Schema validator error
+   *
+   * @param {Object} properties
+   * @api private
+   */
+  constructor(properties) {
+    let msg = properties.message;
+    if (!msg) {
+      msg = MongooseError.messages.general.default;
+    }
 
-  const message = this.formatMessage(msg, properties);
-  MongooseError.call(this, message);
+    const message = formatMessage(msg, properties);
+    super(message);
 
-  properties = Object.assign({}, properties, { message: message });
-  this.name = 'ValidatorError';
-  if (Error.captureStackTrace) {
-    Error.captureStackTrace(this);
-  } else {
-    this.stack = new Error().stack;
+    properties = Object.assign({}, properties, { message: message });
+    this.properties = properties;
+    this.kind = properties.type;
+    this.path = properties.path;
+    this.value = properties.value;
+    this.reason = properties.reason;
+  }
+
+  /*!
+   * toString helper
+   * TODO remove? This defaults to `${this.name}: ${this.message}`
+   */
+  toString() {
+    return this.message;
   }
-  this.properties = properties;
-  this.kind = properties.type;
-  this.path = properties.path;
-  this.value = properties.value;
-  this.reason = properties.reason;
 }
 
-/*!
- * Inherits from MongooseError
- */
 
-ValidatorError.prototype = Object.create(MongooseError.prototype);
-ValidatorError.prototype.constructor = MongooseError;
+Object.defineProperty(ValidatorError.prototype, 'name', {
+  value: 'ValidatorError'
+});
 
 /*!
  * The object used to define this validator. Not enumerable to hide
@@ -55,11 +56,14 @@ Object.defineProperty(ValidatorError.prototype, 'properties', {
   value: null
 });
 
+// Exposed for testing
+ValidatorError.prototype.formatMessage = formatMessage;
+
 /*!
  * Formats error messages
  */
 
-ValidatorError.prototype.formatMessage = function(msg, properties) {
+function formatMessage(msg, properties) {
   if (typeof msg === 'function') {
     return msg(properties);
   }
@@ -73,15 +77,7 @@ ValidatorError.prototype.formatMessage = function(msg, properties) {
   }
 
   return msg;
-};
-
-/*!
- * toString helper
- */
-
-ValidatorError.prototype.toString = function() {
-  return this.message;
-};
+}
 
 /*!
  * exports
diff --git a/lib/error/version.js b/lib/error/version.js
index 9fe92011650..b357fb16ca3 100644
--- a/lib/error/version.js
+++ b/lib/error/version.js
@@ -6,28 +6,28 @@
 
 const MongooseError = require('./');
 
-/**
- * Version Error constructor.
- *
- * @inherits MongooseError
- * @api private
- */
-
-function VersionError(doc, currentVersion, modifiedPaths) {
-  const modifiedPathsStr = modifiedPaths.join(', ');
-  MongooseError.call(this, 'No matching document found for id "' + doc._id +
-    '" version ' + currentVersion + ' modifiedPaths "' + modifiedPathsStr + '"');
-  this.name = 'VersionError';
-  this.version = currentVersion;
-  this.modifiedPaths = modifiedPaths;
+class VersionError extends MongooseError {
+  /**
+   * Version Error constructor.
+   *
+   * @param {Document} doc
+   * @param {Number} currentVersion
+   * @param {Array<String>} modifiedPaths
+   * @api private
+   */
+  constructor(doc, currentVersion, modifiedPaths) {
+    const modifiedPathsStr = modifiedPaths.join(', ');
+    super('No matching document found for id "' + doc._id +
+      '" version ' + currentVersion + ' modifiedPaths "' + modifiedPathsStr + '"');
+    this.version = currentVersion;
+    this.modifiedPaths = modifiedPaths;
+  }
 }
 
-/*!
- * Inherits from MongooseError.
- */
 
-VersionError.prototype = Object.create(MongooseError.prototype);
-VersionError.prototype.constructor = MongooseError;
+Object.defineProperty(VersionError.prototype, 'name', {
+  value: 'VersionError'
+});
 
 /*!
  * exports

From a61defa62a6f2373f97db2ada2a8ec2093f5ec1d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 May 2020 12:10:00 +0200
Subject: [PATCH 0898/2348] test: repro #9030

---
 test/model.test.js | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 52ad90d9252..5b86d149f2e 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6733,4 +6733,40 @@ describe('Model', function() {
     });
   });
 
+  it('casts bulkwrite timestamps to `Number` when specified (gh-9030)', function() {
+    return co(function* () {
+      const userSchema = new Schema({
+        name: String,
+        updatedAt: Number
+      }, { timestamps: true });
+
+      const User = db.model('User', userSchema);
+
+      yield User.create([{ name: 'user1' }, { name: 'user2' }]);
+
+      yield User.bulkWrite([
+        {
+          updateOne: {
+            filter: { name: 'user1' },
+            update: { name: 'new name' }
+          }
+        },
+        {
+          updateMany: {
+            filter: { name: 'user2' },
+            update: { name: 'new name' }
+          }
+        }
+      ]);
+
+      const users = yield User.find().lean();
+      assert(typeof users[0].updatedAt === 'number');
+      assert(typeof users[1].updatedAt === 'number');
+
+      // not-lean queries casts to number even if stored on DB as a date
+      assert.equal(users[0] instanceof User, false);
+      assert.equal(users[1] instanceof User, false);
+    });
+  });
+
 });

From 3fceefe332cea80679cf430f1a9c2a5164ca54af Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 May 2020 12:16:42 +0200
Subject: [PATCH 0899/2348] fix(bulkwrite): cast timestamps when type is
 different than `Date`

---
 lib/helpers/model/castBulkWrite.js | 56 ++++++++++++++++++------------
 test/model.test.js                 |  4 +--
 2 files changed, 36 insertions(+), 24 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index c45ee5d483b..26b7c7f7560 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -45,28 +45,34 @@ module.exports = function castBulkWrite(originalModel, op, options) {
         const strict = options.strict != null ? options.strict : model.schema.options.strict;
 
         _addDiscriminatorToObject(schema, op['updateOne']['filter']);
+
+        if (model.schema.$timestamps != null && op['updateOne'].timestamps !== false) {
+          const createdAt = model.schema.$timestamps.createdAt;
+          const updatedAt = model.schema.$timestamps.updatedAt;
+          applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateOne']['update'], {});
+        }
+
+        applyTimestampsToChildren(now, op['updateOne']['update'], model.schema);
+
+
+        if (op['updateOne'].setDefaultsOnInsert) {
+          setDefaultsOnInsert(op['updateOne']['filter'], model.schema, op['updateOne']['update'], {
+            setDefaultsOnInsert: true,
+            upsert: op['updateOne'].upsert
+          });
+        }
+
         op['updateOne']['filter'] = cast(model.schema, op['updateOne']['filter'], {
           strict: strict,
           upsert: op['updateOne'].upsert
         });
+
         op['updateOne']['update'] = castUpdate(model.schema, op['updateOne']['update'], {
           strict: strict,
           overwrite: false,
           upsert: op['updateOne'].upsert
         });
 
-        if (op['updateOne'].setDefaultsOnInsert) {
-          setDefaultsOnInsert(op['updateOne']['filter'], model.schema, op['updateOne']['update'], {
-            setDefaultsOnInsert: true,
-            upsert: op['updateOne'].upsert
-          });
-        }
-        if (model.schema.$timestamps != null && op['updateOne'].timestamps !== false) {
-          const createdAt = model.schema.$timestamps.createdAt;
-          const updatedAt = model.schema.$timestamps.updatedAt;
-          applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateOne']['update'], {});
-        }
-        applyTimestampsToChildren(now, op['updateOne']['update'], model.schema);
       } catch (error) {
         return callback(error, null);
       }
@@ -83,28 +89,34 @@ module.exports = function castBulkWrite(originalModel, op, options) {
         const schema = model.schema;
         const strict = options.strict != null ? options.strict : model.schema.options.strict;
 
-        _addDiscriminatorToObject(schema, op['updateMany']['filter']);
-        op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter'], {
-          strict: strict,
-          upsert: op['updateMany'].upsert
-        });
-        op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
-          strict: strict,
-          overwrite: false,
-          upsert: op['updateMany'].upsert
-        });
         if (op['updateMany'].setDefaultsOnInsert) {
           setDefaultsOnInsert(op['updateMany']['filter'], model.schema, op['updateMany']['update'], {
             setDefaultsOnInsert: true,
             upsert: op['updateMany'].upsert
           });
         }
+
         if (model.schema.$timestamps != null && op['updateMany'].timestamps !== false) {
           const createdAt = model.schema.$timestamps.createdAt;
           const updatedAt = model.schema.$timestamps.updatedAt;
           applyTimestampsToUpdate(now, createdAt, updatedAt, op['updateMany']['update'], {});
         }
+
         applyTimestampsToChildren(now, op['updateMany']['update'], model.schema);
+
+        _addDiscriminatorToObject(schema, op['updateMany']['filter']);
+
+        op['updateMany']['filter'] = cast(model.schema, op['updateMany']['filter'], {
+          strict: strict,
+          upsert: op['updateMany'].upsert
+        });
+
+        op['updateMany']['update'] = castUpdate(model.schema, op['updateMany']['update'], {
+          strict: strict,
+          overwrite: false,
+          upsert: op['updateMany'].upsert
+        });
+
       } catch (error) {
         return callback(error, null);
       }
diff --git a/test/model.test.js b/test/model.test.js
index 5b86d149f2e..330698b2b80 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6760,8 +6760,8 @@ describe('Model', function() {
       ]);
 
       const users = yield User.find().lean();
-      assert(typeof users[0].updatedAt === 'number');
-      assert(typeof users[1].updatedAt === 'number');
+      assert.equal(typeof users[0].updatedAt, 'number');
+      assert.equal(typeof users[1].updatedAt, 'number');
 
       // not-lean queries casts to number even if stored on DB as a date
       assert.equal(users[0] instanceof User, false);

From 89451927edbdd91c15dc325b7b1979d484b576c7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 May 2020 19:52:37 +0200
Subject: [PATCH 0900/2348] test: repro #9032

---
 test/index.test.js | 52 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/test/index.test.js b/test/index.test.js
index a8025689c86..bb9e070c74a 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -778,5 +778,57 @@ describe('mongoose module:', function() {
         done();
       });
     });
+
+    it('can set `setDefaultsOnInsert` as a global option (gh-9032)', function() {
+      return co(function* () {
+        const m = new mongoose.Mongoose();
+        m.set('setDefaultsOnInsert', true);
+        const db = yield m.connect('mongodb://localhost:27017/mongoose_test_9032');
+
+        const schema = new m.Schema({
+          title: String,
+          genre: { type: String, default: 'Action' }
+        }, { collection: 'movies_1' });
+
+        const Movie = db.model('Movie', schema);
+
+
+        yield Movie.updateOne(
+          {},
+          { title: 'Cloud Atlas' },
+          { upsert: true }
+        );
+
+        // lean is necessary to avoid defaults by casting
+        const movie = yield Movie.findOne({ title: 'Cloud Atlas' }).lean();
+        assert.equal(movie.genre, 'Action');
+      });
+    });
+
+    it('setting `setDefaultOnInsert` on operation has priority over base option (gh-9032)', function() {
+      return co(function* () {
+        const m = new mongoose.Mongoose();
+        m.set('setDefaultsOnInsert', true);
+        const db = yield m.connect('mongodb://localhost:27017/mongoose_test_9032');
+
+        const schema = new m.Schema({
+          title: String,
+          genre: { type: String, default: 'Action' }
+        }, { collection: 'movies_2' });
+
+        const Movie = db.model('Movie', schema);
+
+
+        yield Movie.updateOne(
+          {},
+          { title: 'The Man From Earth' },
+          { upsert: true, setDefaultsOnInsert: false }
+        );
+
+        // lean is necessary to avoid defaults by casting
+        const movie = yield Movie.findOne({ title: 'The Man From Earth' }).lean();
+        assert.ok(!movie.genre);
+      });
+    });
   });
 });

From 4833de1b3649d89cd38adcbb39143dd5102c9ecc Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 19 May 2020 19:54:07 +0200
Subject: [PATCH 0901/2348] feat(mongoose): add support for setting
 `setDefaultsOnInsert` as a global option

---
 lib/helpers/setDefaultsOnInsert.js | 17 +++++++++++------
 lib/validoptions.js                |  1 +
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/lib/helpers/setDefaultsOnInsert.js b/lib/helpers/setDefaultsOnInsert.js
index 0545e80d3d4..747cb61ab8d 100644
--- a/lib/helpers/setDefaultsOnInsert.js
+++ b/lib/helpers/setDefaultsOnInsert.js
@@ -14,6 +14,17 @@ const modifiedPaths = require('./common').modifiedPaths;
  */
 
 module.exports = function(filter, schema, castedDoc, options) {
+  options = options || {};
+
+  const shouldSetDefaultsOnInsert =
+    options.hasOwnProperty('setDefaultsOnInsert') ?
+      options.setDefaultsOnInsert :
+      schema.base.options.setDefaultsOnInsert;
+
+  if (!options.upsert || !shouldSetDefaultsOnInsert) {
+    return castedDoc;
+  }
+
   const keys = Object.keys(castedDoc || {});
   const updatedKeys = {};
   const updatedValues = {};
@@ -22,12 +33,6 @@ module.exports = function(filter, schema, castedDoc, options) {
 
   let hasDollarUpdate = false;
 
-  options = options || {};
-
-  if (!options.upsert || !options.setDefaultsOnInsert) {
-    return castedDoc;
-  }
-
   for (let i = 0; i < numKeys; ++i) {
     if (keys[i].startsWith('$')) {
       modifiedPaths(castedDoc[keys[i]], '', modified);
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 9464e4d8611..3ff4ada636c 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -16,6 +16,7 @@ const VALID_OPTIONS = Object.freeze([
   'objectIdGetter',
   'runValidators',
   'selectPopulatedPaths',
+  'setDefaultsOnInsert',
   'strict',
   'toJSON',
   'toObject',

From 0f73556a5bae75ede26adad2111e99c462170a28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 May 2020 23:04:44 -0400
Subject: [PATCH 0902/2348] chore: upgrade opencollective sponsors

---
 index.pug | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/index.pug b/index.pug
index 47fb9de2f81..6c9b57e908c 100644
--- a/index.pug
+++ b/index.pug
@@ -352,6 +352,24 @@ html(lang='en')
               <a href="https://www.parhaatnettikasinot.com/">
                 <img class="sponsor" src="https://images.opencollective.com/parhaatnettikasinot-com/fc53017/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://swisscasinohex.com/online-casinos/">
+                <img class="sponsor" src="https://images.opencollective.com/swisscasinohex-com/107940c/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://onlinecasinohex.nl/online-casinos/nederland/">
+                <img class="sponsor" src="https://images.opencollective.com/onlinecasinohex-nl/ed24082/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://kasynohex.com/kasyna-online/">
+                <img class="sponsor" src="https://images.opencollective.com/kasynohex-com/b25daf6/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://casinohex.ro/online-cazino/">
+                <img class="sponsor" src="https://images.opencollective.com/casinohex-ro/493996e/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://norskcasinohex.com/casino-pa-nett/">
+                <img class="sponsor" src="https://images.opencollective.com/norskcasinohex-com/f0d4c76/logo/256.png" style="height: 100px">
+              </a>
+              <a href="https://aussiecasinohex.com/online-casinos/">
+                <img class="sponsor" src="https://images.opencollective.com/aussiecasinohex/923df37/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From cc815b3d0ec16db91b4cba0cb6f5986eab706e0e Mon Sep 17 00:00:00 2001
From: Victor Chiletto <victor.chiletto@b2wdigital.com>
Date: Wed, 20 May 2020 15:31:43 -0300
Subject: [PATCH 0903/2348] test(document): repro #9039

---
 test/document.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index cb1b3976ffc..75b3a5be62b 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9000,4 +9000,20 @@ describe('document', function() {
       assert.ok(!user.updatedAt);
     });
   });
+
+  it('Sets default when passing undefined as value for a key in a nested subdoc (gh-????)', function() {
+    const Test = db.model('Test', {
+      nested: {
+        prop: {
+          type: String,
+          default: 'some default value'
+        }
+      }
+    });
+
+    return co(function*() {
+      const doc = yield Test.create({ nested: { prop: undefined } });
+      assert.equal(doc.nested.prop, 'some default value');
+    });
+  });
 });

From 18435335af710a3cb775b1476713b1acb373223e Mon Sep 17 00:00:00 2001
From: Victor Chiletto <victor.chiletto@b2wdigital.com>
Date: Wed, 20 May 2020 15:33:09 -0300
Subject: [PATCH 0904/2348] fix(document): don't overwrite defaults with
 undefined keys in nested documents

Fixes #9039
---
 lib/document.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f59a1bb617e..9fcbe939f2c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -957,9 +957,9 @@ Document.prototype.$set = function $set(path, val, type, options) {
       this.$__.$setCalled.add(prefix + key);
       this.$set(path[key], prefix + key, constructing, options);
     } else if (strict) {
-      // Don't overwrite defaults with undefined keys (gh-3981)
+      // Don't overwrite defaults with undefined keys (gh-3981) (gh-9039)
       if (constructing && path[key] === void 0 &&
-          this.get(key) !== void 0) {
+          this.get(pathName) !== void 0) {
         return;
       }
 

From ab4f1e96df1673185c390720e0a52b36ee58b63d Mon Sep 17 00:00:00 2001
From: Victor Chiletto <victor.chiletto@b2wdigital.com>
Date: Wed, 20 May 2020 16:03:13 -0300
Subject: [PATCH 0905/2348] tests(document): add GitHub issue number

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 75b3a5be62b..37b8c0f455d 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9001,7 +9001,7 @@ describe('document', function() {
     });
   });
 
-  it('Sets default when passing undefined as value for a key in a nested subdoc (gh-????)', function() {
+  it('Sets default when passing undefined as value for a key in a nested subdoc (gh-9039)', function() {
     const Test = db.model('Test', {
       nested: {
         prop: {

From 5cf9d2fe01a2f05844a1cd0f1cd915fb361c573a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 May 2020 11:34:31 -0400
Subject: [PATCH 0906/2348] test: repro #9042

---
 test/model.discriminator.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 357efc92820..d805a35b301 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1584,4 +1584,20 @@ describe('model', function() {
 
     assert.ok(SuperUser.schema.path('ability'));
   });
+
+  it('removes paths underneath mixed type if discriminator schema sets path to mixed (gh-9042)', function() {
+    const TestSchema = Schema({ name: String });
+    const MainSchema = Schema({ run: { tab: TestSchema } }, {
+      discriminatorKey: 'type'
+    });
+    const Main = db.model('Test', MainSchema);
+
+    const DiscriminatorSchema = Schema({ run: {} });
+
+    const D = Main.discriminator('copy', DiscriminatorSchema);
+    assert.ok(!D.schema.paths['run.tab']);
+
+    const doc = new D({ run: { tab: { id: 42 } } });
+    assert.ifError(doc.validateSync());
+  });
 });

From 9b082a4a485704819633a84e202ed03accaab81a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 May 2020 11:35:29 -0400
Subject: [PATCH 0907/2348] fix(discriminator): remove discriminator schema
 nested paths pulled from base schema underneath a mixed path in discriminator
 schema

Fix #9042
---
 lib/helpers/model/discriminator.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index d689e1c6c1b..b0c446345f8 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -85,6 +85,18 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
       if (schema.nested[path]) {
         conflictingPaths.push(path);
       }
+
+      if (path.indexOf('.') === -1) {
+        continue;
+      }
+      const sp = path.split('.');
+      let cur = '';
+      for (const piece of sp) {
+        cur += (cur.length ? '.' : '') + piece;
+        if (schema.paths[cur] || schema.singleNestedPaths[cur]) {
+          conflictingPaths.push(path);
+        }
+      }
     }
 
     utils.merge(schema, baseSchema, {

From 64ea7cf5250bb90d400cdc5280b23dd499d0a030 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 May 2020 13:11:25 -0400
Subject: [PATCH 0908/2348] fix(document): make internal `$__.scope` property a
 symbol instead to work around a bug with fast-safe-stringify

Fix #8955
---
 lib/helpers/document/compile.js | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index f6eb160adee..24e909ddd27 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -6,6 +6,7 @@ const getSymbol = require('../../helpers/symbols').getSymbol;
 const utils = require('../../utils');
 
 let Document;
+const scopeSymbol = Symbol('mongoose#Document#scope');
 
 /*!
  * exports
@@ -61,7 +62,7 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
 
           // save scope for nested getters/setters
           if (!prefix) {
-            nested.$__.scope = this;
+            nested.$__[scopeSymbol] = this;
           }
           nested.$__.nestedPath = path;
 
@@ -133,7 +134,7 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
         if (v instanceof Document) {
           v = v.toObject({ transform: false });
         }
-        const doc = this.$__.scope || this;
+        const doc = this.$__[scopeSymbol] || this;
         return doc.$set(path, v);
       }
     });
@@ -142,10 +143,10 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
       enumerable: true,
       configurable: true,
       get: function() {
-        return this[getSymbol].call(this.$__.scope || this, path);
+        return this[getSymbol].call(this.$__[scopeSymbol] || this, path);
       },
       set: function(v) {
-        return this.$set.call(this.$__.scope || this, path, v);
+        return this.$set.call(this.$__[scopeSymbol] || this, path, v);
       }
     });
   }

From cf2ba9ff698d8b3bca4eee447125484b46053cd1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 May 2020 14:12:48 -0400
Subject: [PATCH 0909/2348] fix(model): make syncIndexes() not drop index if
 all user-specified collation options are the same

Fix #8994
---
 lib/helpers/indexes/isIndexEqual.js       | 48 ++++++++++++++++++++++
 lib/model.js                              | 49 +++--------------------
 test/helpers/indexes.isIndexEqual.test.js | 36 +++++++++++++++++
 3 files changed, 89 insertions(+), 44 deletions(-)
 create mode 100644 lib/helpers/indexes/isIndexEqual.js
 create mode 100644 test/helpers/indexes.isIndexEqual.test.js

diff --git a/lib/helpers/indexes/isIndexEqual.js b/lib/helpers/indexes/isIndexEqual.js
new file mode 100644
index 00000000000..f3d7e1668c7
--- /dev/null
+++ b/lib/helpers/indexes/isIndexEqual.js
@@ -0,0 +1,48 @@
+'use strict';
+
+const get = require('../get');
+const utils = require('../../utils');
+
+module.exports = function isIndexEqual(key, options, dbIndex) {
+  // If these options are different, need to rebuild the index
+  const optionKeys = [
+    'unique',
+    'partialFilterExpression',
+    'sparse',
+    'expireAfterSeconds',
+    'collation'
+  ];
+  for (const key of optionKeys) {
+    if (!(key in options) && !(key in dbIndex)) {
+      continue;
+    }
+    if (key === 'collation') {
+      const definedKeys = Object.keys(options.collation);
+      const schemaCollation = options.collation;
+      const dbCollation = dbIndex.collation;
+      for (const opt of definedKeys) {
+        if (get(schemaCollation, opt) !== get(dbCollation, opt)) {
+          return false;
+        }
+      }
+    } else if (!utils.deepEqual(options[key], dbIndex[key])) {
+      return false;
+    }
+  }
+
+  const schemaIndexKeys = Object.keys(key);
+  const dbIndexKeys = Object.keys(dbIndex.key);
+  if (schemaIndexKeys.length !== dbIndexKeys.length) {
+    return false;
+  }
+  for (let i = 0; i < schemaIndexKeys.length; ++i) {
+    if (schemaIndexKeys[i] !== dbIndexKeys[i]) {
+      return false;
+    }
+    if (!utils.deepEqual(key[schemaIndexKeys[i]], dbIndex.key[dbIndexKeys[i]])) {
+      return false;
+    }
+  }
+
+  return true;
+};
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index 7fe206f22c6..53fe89ff2f9 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -38,6 +38,7 @@ const getModelsMapForPopulate = require('./helpers/populate/getModelsMapForPopul
 const immediate = require('./helpers/immediate');
 const internalToObjectOptions = require('./options').internalToObjectOptions;
 const isDefaultIdIndex = require('./helpers/indexes/isDefaultIdIndex');
+const isIndexEqual = require('./helpers/indexes/isIndexEqual');
 const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedInclusive');
 const get = require('./helpers/get');
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
@@ -1408,7 +1409,10 @@ Model.cleanIndexes = function cleanIndexes(callback) {
         }
 
         for (const schemaIndex of schemaIndexes) {
-          if (isIndexEqual(this, schemaIndex, index)) {
+          const key = schemaIndex[0];
+          const options = _decorateDiscriminatorIndexOptions(this,
+            utils.clone(schemaIndex[1]));
+          if (isIndexEqual(key, options, index)) {
             found = true;
           }
         }
@@ -1443,49 +1447,6 @@ Model.cleanIndexes = function cleanIndexes(callback) {
   });
 };
 
-/*!
- * ignore
- */
-
-function isIndexEqual(model, schemaIndex, dbIndex) {
-  const key = schemaIndex[0];
-  const options = _decorateDiscriminatorIndexOptions(model,
-    utils.clone(schemaIndex[1]));
-
-  // If these options are different, need to rebuild the index
-  const optionKeys = [
-    'unique',
-    'partialFilterExpression',
-    'sparse',
-    'expireAfterSeconds',
-    'collation'
-  ];
-  for (const key of optionKeys) {
-    if (!(key in options) && !(key in dbIndex)) {
-      continue;
-    }
-    if (!utils.deepEqual(options[key], dbIndex[key])) {
-      return false;
-    }
-  }
-
-  const schemaIndexKeys = Object.keys(key);
-  const dbIndexKeys = Object.keys(dbIndex.key);
-  if (schemaIndexKeys.length !== dbIndexKeys.length) {
-    return false;
-  }
-  for (let i = 0; i < schemaIndexKeys.length; ++i) {
-    if (schemaIndexKeys[i] !== dbIndexKeys[i]) {
-      return false;
-    }
-    if (!utils.deepEqual(key[schemaIndexKeys[i]], dbIndex.key[dbIndexKeys[i]])) {
-      return false;
-    }
-  }
-
-  return true;
-}
-
 /**
  * Lists the indexes currently defined in MongoDB. This may or may not be
  * the same as the indexes defined in your schema depending on whether you
diff --git a/test/helpers/indexes.isIndexEqual.test.js b/test/helpers/indexes.isIndexEqual.test.js
new file mode 100644
index 00000000000..44a8df490c0
--- /dev/null
+++ b/test/helpers/indexes.isIndexEqual.test.js
@@ -0,0 +1,36 @@
+'use strict';
+
+const assert = require('assert');
+const isIndexEqual = require('../../lib/helpers/indexes/isIndexEqual');
+
+describe('isIndexEqual', function() {
+  it('ignores default collation options when comparing collations (gh-8994)', function() {
+    const key = { username: 1 };
+    const options = {
+      unique: true,
+      collation: {
+        locale: 'en',
+        strength: 2
+      }
+    };
+    const dbIndex = {
+      unique: true,
+      key: { username: 1 },
+      name: 'username_1',
+      background: true,
+      collation: {
+        locale: 'en',
+        caseLevel: false,
+        caseFirst: 'off',
+        strength: 2,
+        numericOrdering: false,
+        version: '57.1'
+      }
+    };
+
+    assert.ok(isIndexEqual(key, options, dbIndex));
+
+    dbIndex.collation.locale = 'de';
+    assert.ok(!isIndexEqual(key, options, dbIndex));
+  });
+});
\ No newline at end of file

From 8fec66c57a82fa7054913720161194161e65bb8f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 May 2020 14:53:30 -0400
Subject: [PATCH 0910/2348] fix(document): fix one more dangling $__.scope
 reference re: #8955

---
 lib/document.js                 | 3 ++-
 lib/helpers/document/compile.js | 4 ++--
 lib/helpers/symbols.js          | 1 +
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 9fcbe939f2c..51080c0fabd 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -41,6 +41,7 @@ const documentArrayParent = require('./helpers/symbols').documentArrayParent;
 const documentSchemaSymbol = require('./helpers/symbols').documentSchemaSymbol;
 const getSymbol = require('./helpers/symbols').getSymbol;
 const populateModelSymbol = require('./helpers/symbols').populateModelSymbol;
+const scopeSymbol = require('./helpers/symbols').scopeSymbol;
 
 let DocumentArray;
 let MongooseArray;
@@ -3575,7 +3576,7 @@ Document.prototype.populate = function populate() {
     this.$__.populate = undefined;
     let topLevelModel = this.constructor;
     if (this.$__isNested) {
-      topLevelModel = this.$__.scope.constructor;
+      topLevelModel = this.$__[scopeSymbol].constructor;
       const nestedPath = this.$__.nestedPath;
       paths.forEach(function(populateOptions) {
         populateOptions.path = nestedPath + '.' + populateOptions.path;
diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index 24e909ddd27..56dffa1e07e 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -2,11 +2,11 @@
 
 const documentSchemaSymbol = require('../../helpers/symbols').documentSchemaSymbol;
 const get = require('../../helpers/get');
-const getSymbol = require('../../helpers/symbols').getSymbol;
 const utils = require('../../utils');
 
 let Document;
-const scopeSymbol = Symbol('mongoose#Document#scope');
+const getSymbol = require('../../helpers/symbols').getSymbol;
+const scopeSymbol = require('../../helpers/symbols').scopeSymbol;
 
 /*!
  * exports
diff --git a/lib/helpers/symbols.js b/lib/helpers/symbols.js
index 3860f237743..746f8935557 100644
--- a/lib/helpers/symbols.js
+++ b/lib/helpers/symbols.js
@@ -11,4 +11,5 @@ exports.modelSymbol = Symbol('mongoose#Model');
 exports.objectIdSymbol = Symbol('mongoose#ObjectId');
 exports.populateModelSymbol = Symbol('mongoose.PopulateOptions#Model');
 exports.schemaTypeSymbol = Symbol('mongoose#schemaType');
+exports.scopeSymbol = Symbol('mongoose#Document#scope');
 exports.validatorErrorSymbol = Symbol('mongoose:validatorError');
\ No newline at end of file

From f1e420111b5673979d79b0018956472b3b404d3d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 23 May 2020 15:08:52 -0400
Subject: [PATCH 0911/2348] fix(query): throw CastError if filter `$and`,
 `$or`, `$nor` contain non-object values

Fix #8948
---
 lib/cast.js        | 15 ++++++++++++---
 test/query.test.js | 21 ++++++++++++++++++++-
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/lib/cast.js b/lib/cast.js
index 7e229638f68..b047939948f 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -4,6 +4,7 @@
  * Module dependencies.
  */
 
+const CastError = require('./error/cast');
 const StrictModeError = require('./error/strict');
 const Types = require('./schema/index');
 const castTextSearch = require('./schema/operators/text');
@@ -29,6 +30,10 @@ module.exports = function cast(schema, obj, options, context) {
     throw new Error('Query filter must be an object, got an array ', util.inspect(obj));
   }
 
+  if (obj == null) {
+    return obj;
+  }
+
   // bson 1.x has the unfortunate tendency to remove filters that have a top-level
   // `_bsontype` property. But we should still allow ObjectIds because
   // `Collection#find()` has a special case to support `find(objectid)`.
@@ -54,9 +59,13 @@ module.exports = function cast(schema, obj, options, context) {
     val = obj[path];
 
     if (path === '$or' || path === '$nor' || path === '$and') {
-      let k = val.length;
-
-      while (k--) {
+      if (!Array.isArray(val)) {
+        throw new CastError('Array', val, path);
+      }
+      for (let k = 0; k < val.length; ++k) {
+        if (val[k] == null || typeof val[k] !== 'object') {
+          throw new CastError('Object', val[k], path + '.' + k);
+        }
         val[k] = cast(schema, val[k], options, context);
       }
     } else if (path === '$where') {
diff --git a/test/query.test.js b/test/query.test.js
index bc0b27ea519..97a3defe70c 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3631,7 +3631,7 @@ describe('Query', function() {
   });
 
   it('casts update object according to child discriminator schema when `discriminatorKey` is present (gh-8982)', function() {
-    const userSchema = new Schema({ }, { discriminatorKey: 'kind' });
+    const userSchema = new Schema({}, { discriminatorKey: 'kind' });
     const Person = db.model('Person', userSchema);
 
     return co(function*() {
@@ -3646,4 +3646,23 @@ describe('Query', function() {
       assert.deepEqual(person.locations, ['US', 'UK']);
     });
   });
+
+  it('throws readable error if `$and` and `$or` contain non-objects (gh-8948)', function() {
+    const userSchema = new Schema({ name: String });
+    const Person = db.model('Person', userSchema);
+
+    return co(function*() {
+      let err = yield Person.find({ $and: [null] }).catch(err => err);
+      assert.equal(err.name, 'CastError');
+      assert.equal(err.path, '$and.0');
+
+      err = yield Person.find({ $or: [false] }).catch(err => err);
+      assert.equal(err.name, 'CastError');
+      assert.equal(err.path, '$or.0');
+
+      err = yield Person.find({ $nor: ['not an object'] }).catch(err => err);
+      assert.equal(err.name, 'CastError');
+      assert.equal(err.path, '$nor.0');
+    });
+  });
 });

From c382a57ba1e678ad8dced33d3110c03a75464862 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 25 May 2020 01:36:22 +0200
Subject: [PATCH 0912/2348] upgrade eslint to 7.1.0

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 2830a991e0a..8a23a7eb67f 100644
--- a/package.json
+++ b/package.json
@@ -44,7 +44,7 @@
     "cheerio": "1.0.0-rc.2",
     "co": "4.6.0",
     "dox": "0.3.1",
-    "eslint": "6.8.0",
+    "eslint": "7.1.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.1.0",
     "lodash.isequal": "4.5.0",

From adbf7102ad6aa02be9543fe64e09594af6500f0c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 25 May 2020 01:49:09 +0200
Subject: [PATCH 0913/2348] lint(document): remove impossible to execute branch

---
 lib/document.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 51080c0fabd..88bb7198684 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2934,8 +2934,6 @@ Document.prototype.$__handleReject = function handleReject(err) {
     this.emit('error', err);
   } else if (this.constructor.listeners && this.constructor.listeners('error').length) {
     this.constructor.emit('error', err);
-  } else if (this.listeners && this.listeners('error').length) {
-    this.emit('error', err);
   }
 };
 

From bd2aa99c450aa2a477ee43a0d5561bbdf89ca11e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 25 May 2020 01:49:35 +0200
Subject: [PATCH 0914/2348] lint(compile): fix no-setter-return

---
 lib/helpers/document/compile.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index 56dffa1e07e..cc1b49ac492 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -135,7 +135,7 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
           v = v.toObject({ transform: false });
         }
         const doc = this.$__[scopeSymbol] || this;
-        return doc.$set(path, v);
+        doc.$set(path, v);
       }
     });
   } else {
@@ -146,7 +146,7 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
         return this[getSymbol].call(this.$__[scopeSymbol] || this, path);
       },
       set: function(v) {
-        return this.$set.call(this.$__[scopeSymbol] || this, path, v);
+        this.$set.call(this.$__[scopeSymbol] || this, path, v);
       }
     });
   }

From 9a21a5bf0d2efaa4bdb3756afd038bbd8332a13d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 25 May 2020 02:32:00 +0200
Subject: [PATCH 0915/2348] enhancement(connection): make server selection
 error less deterministic

---
 lib/error/serverSelection.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index 13f96b753f6..a8bab5fa581 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -38,9 +38,10 @@ MongooseServerSelectionError.prototype.constructor = MongooseError;
  * ignore
  */
 
-const atlasMessage = 'Could not connect to any servers in your MongoDB Atlas ' +
-  'cluster. Make sure your current IP address is on your Atlas cluster\'s IP ' +
-  'whitelist: https://docs.atlas.mongodb.com/security-whitelist/.';
+const atlasMessage = 'Could not connect to any servers in your MongoDB Atlas cluster. ' +
+  'One common reason is that you\'re trying to access the database from ' +
+  'an IP that isn\'t whitelisted. Make sure your current IP address is on your Atlas ' +
+  'cluster\'s IP whitelist: https://docs.atlas.mongodb.com/security-whitelist/';
 
 MongooseServerSelectionError.prototype.assimilateError = function(err) {
   const reason = err.reason;

From 54b3cae3d1fd2d2243c0cb60ef5dd3fd0d13760f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 25 May 2020 13:44:57 -0400
Subject: [PATCH 0916/2348] chore: release 5.9.16

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 068fece6ef0..4ed61986e42 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.9.16 / 2020-05-25
+===================
+ * perf(error): convert errors to classes extending Error for lower CPU overhead #9021 [zbjornson](https://github.com/zbjornson)
+ * fix(query): throw CastError if filter `$and`, `$or`, `$nor` contain non-object values #8948
+ * fix(bulkwrite): cast filter & update to schema after applying timestamps #9030 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(document): don't overwrite defaults with undefined keys in nested documents #9039 [vitorhnn](https://github.com/vitorhnn)
+ * fix(discriminator): remove discriminator schema nested paths pulled from base schema underneath a mixed path in discriminator schema #9042
+ * fix(model): make syncIndexes() not drop index if all user-specified collation options are the same #8994
+ * fix(document): make internal `$__.scope` property a symbol instead to work around a bug with fast-safe-stringify #8955
+ * docs: model.findByIdAndUpdate() 'new' param fix #9026 [dandv](https://github.com/dandv)
+
 5.9.15 / 2020-05-18
 ===================
  * fix(schema): treat creating dotted path with no parent as creating a nested path #9020
diff --git a/package.json b/package.json
index 8a23a7eb67f..ac53f420548 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.15",
+  "version": "5.9.16",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From edfb32a443dd714aed9c445c69643c588659bf4d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 25 May 2020 15:26:40 -0400
Subject: [PATCH 0917/2348] docs: add some blog post links

---
 docs/schematypes.pug | 8 ++++++--
 docs/subdocs.pug     | 2 +-
 lib/model.js         | 6 ++++++
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 6984ec12e09..dc0dcabd2fd 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -32,6 +32,7 @@ block content
       <li><a href="#schematype-options">SchemaType Options</a></li>
       <li><a href="#customtypes">Creating Custom Types</a></li>
       <li><a href="#path">The `schema.path()` Function</a></li>
+      <li><a href="#further-reading">Further Reading</a></li>
     </ul>
 
     * [What is a SchemaType?](#what-is-a-schematype)
@@ -692,6 +693,9 @@ block content
     You can use this function to inspect the schema type for a given path,
     including what validators it has and what the type is.
 
-    <h3 id="next"><a href="#next">Next Up</a></h3>
+    <h3 id="further-reading"><a href="#further-reading">Further Reading</a></h3>
 
-    Now that we've covered `SchemaTypes`, let's take a look at [Connections](/docs/connections.html).
+    <ul>
+      <li><a href="https://masteringjs.io/tutorials/mongoose/schematype">An Introduction to Mongoose SchemaTypes</a></li>
+      <li><a href="https://kb.objectrocket.com/mongo-db/mongoose-schema-types-1418">Mongoose Schema Types</a></li>
+    </ul>
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index cec31d3c16b..d489aa4b68a 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -20,7 +20,7 @@ block content
 
     Subdocuments are documents embedded in other documents. In Mongoose, this
     means you can nest schemas in other schemas. Mongoose has two
-    distinct notions of subdocuments: arrays of subdocuments and single nested
+    distinct notions of subdocuments: [arrays of subdocuments](https://masteringjs.io/tutorials/mongoose/array#document-arrays) and single nested
     subdocuments.
     ```javascript
     var childSchema = new Schema({ name: 'string' });
diff --git a/lib/model.js b/lib/model.js
index 53fe89ff2f9..62e79dccd0c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3934,6 +3934,12 @@ Model.mapReduce = function mapReduce(o, callback) {
  * - Mongoose does **not** cast aggregation pipelines to the model's schema because `$project` and `$group` operators allow redefining the "shape" of the documents at any stage of the pipeline, which may leave documents in an incompatible format. You can use the [mongoose-cast-aggregation plugin](https://github.com/AbdelrahmanHafez/mongoose-cast-aggregation) to enable minimal casting for aggregation pipelines.
  * - The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).
  *
+ * #### More About Aggregations:
+ * 
+ * - [Mongoose `Aggregate`](/docs/api/aggregate.html)
+ * - [An Introduction to Mongoose Aggregate](https://masteringjs.io/tutorials/mongoose/aggregate)
+ * - [MongoDB Aggregation docs](http://docs.mongodb.org/manual/applications/aggregation/)
+ * 
  * @see Aggregate #aggregate_Aggregate
  * @see MongoDB http://docs.mongodb.org/manual/applications/aggregation/
  * @param {Array} [pipeline] aggregation pipeline as an array of objects

From 3558db9848b42f91a306789f31d7a42f739136a3 Mon Sep 17 00:00:00 2001
From: Ismet Togay <ismet.togay@gmail.com>
Date: Tue, 26 May 2020 17:02:11 +0300
Subject: [PATCH 0918/2348] fix docs: variable name

---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index e71cfefe32d..5f9b9f59335 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -853,7 +853,7 @@ block content
     var schema = new Schema({ name: String });
     schema.set('validateBeforeSave', false);
     schema.path('name').validate(function (value) {
-        return v != null;
+        return value != null;
     });
     var M = mongoose.model('Person', schema);
     var m = new M({ name: null });

From 94e5935a994c63eb0699b24a637f276fd66c5536 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Tue, 26 May 2020 20:03:54 -0700
Subject: [PATCH 0919/2348] Clarify parameters passed to .debug. Fix #9029.

---
 lib/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 8c7c9f0aa90..024d65afd96 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -141,10 +141,10 @@ Mongoose.prototype.driver = require('./driver');
  *
  *     mongoose.set('debug', true) // enable logging collection methods + arguments to the console
  *
- *     mongoose.set('debug', function(collectionName, methodName, arg1, arg2...) {}); // use custom function to log collection methods + arguments
+ *     mongoose.set('debug', function(collectionName, methodName, ...methodArgs) {}); // use custom function to log collection methods + arguments
  *
  * Currently supported options are:
- * - 'debug': prints the operations mongoose sends to MongoDB to the console
+ * - 'debug': If `true`, prints the operations mongoose sends to MongoDB to the console. If a callback function is passed, it will receive the collection name, the method name, then all arugments passed to the method. For example, if you wanted to replicate the default logging, you could output from the callback `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
  * - 'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models
  * - 'useCreateIndex': false by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
  * - 'useFindAndModify': true by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.

From 06aae06c486b28e12b4000c62e29f7e90ee9041e Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Tue, 26 May 2020 20:35:31 -0700
Subject: [PATCH 0920/2348] Mention logging to writable sreams

---
 lib/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 024d65afd96..4b1b72e4cdb 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -139,12 +139,12 @@ Mongoose.prototype.driver = require('./driver');
  *
  *     mongoose.set('test', value) // sets the 'test' option to `value`
  *
- *     mongoose.set('debug', true) // enable logging collection methods + arguments to the console
+ *     mongoose.set('debug', true) // enable logging collection methods + arguments to the console/file
  *
  *     mongoose.set('debug', function(collectionName, methodName, ...methodArgs) {}); // use custom function to log collection methods + arguments
  *
  * Currently supported options are:
- * - 'debug': If `true`, prints the operations mongoose sends to MongoDB to the console. If a callback function is passed, it will receive the collection name, the method name, then all arugments passed to the method. For example, if you wanted to replicate the default logging, you could output from the callback `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
+ * - 'debug': If `true`, prints the operations mongoose sends to MongoDB to the console. If a writable stream is passed, it will log to that stream, without colorization. If a callback function is passed, it will receive the collection name, the method name, then all arugments passed to the method. For example, if you wanted to replicate the default logging, you could output from the callback `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
  * - 'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models
  * - 'useCreateIndex': false by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
  * - 'useFindAndModify': true by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.

From c170808e323f79ce0dc36be304200d1ecc1284b2 Mon Sep 17 00:00:00 2001
From: Ismet Togay <ismet.togay@gmail.com>
Date: Wed, 27 May 2020 12:18:00 +0300
Subject: [PATCH 0921/2348] docs: fix property value in Getters example

---
 docs/schematypes.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index dc0dcabd2fd..410e2992001 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -618,7 +618,7 @@ block content
 
     const doc = new User({ name: 'Val', picture: '/123.png' });
     doc.picture; // 'https://s3.amazonaws.com/mybucket/123.png'
-    doc.toObject({ getters: false }).picture; // '123.png'
+    doc.toObject({ getters: false }).picture; // '/123.png'
     ```
 
     Generally, you only use getters on primitive paths as opposed to arrays

From f06315e0ee13e70705cf42639a9862f286ae1be3 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 28 May 2020 19:46:32 +0200
Subject: [PATCH 0922/2348] upgrade mongodb to v3.5.8

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index ac53f420548..8e9291dddc3 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.5.7",
+    "mongodb": "3.5.8",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From e87d78eb0d67630c59c9fa85bdf1163e78382217 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 29 May 2020 06:06:22 +0200
Subject: [PATCH 0923/2348] style: fix lint errors

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 62e79dccd0c..1bf09b7ba90 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3935,11 +3935,11 @@ Model.mapReduce = function mapReduce(o, callback) {
  * - The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).
  *
  * #### More About Aggregations:
- * 
+ *
  * - [Mongoose `Aggregate`](/docs/api/aggregate.html)
  * - [An Introduction to Mongoose Aggregate](https://masteringjs.io/tutorials/mongoose/aggregate)
  * - [MongoDB Aggregation docs](http://docs.mongodb.org/manual/applications/aggregation/)
- * 
+ *
  * @see Aggregate #aggregate_Aggregate
  * @see MongoDB http://docs.mongodb.org/manual/applications/aggregation/
  * @param {Array} [pipeline] aggregation pipeline as an array of objects

From b7c65727de7c7454cbb4d8adff715b8a5609ffeb Mon Sep 17 00:00:00 2001
From: Tigran <tigran.contact@gmail.com>
Date: Sun, 31 May 2020 00:43:17 +0400
Subject: [PATCH 0924/2348] Update faq.pug

---
 docs/faq.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index 59f08721765..b36e211ac0b 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -112,7 +112,7 @@ block content
     // Promise based alternative. `init()` returns a promise that resolves
     // when the indexes have finished building successfully. The `init()`
     // function is idempotent, so don't worry about triggering an index rebuild.
-    Model.init().then(function() {
+    Model.init().then(function(err) {
       assert.ifError(err);
       Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
         console.log(err);

From ab8def113838778c32d9ec600817bc7e304e4b2e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 31 May 2020 08:19:19 +0200
Subject: [PATCH 0925/2348] docs(document): add validateModifiedOnly to
 Document#save(), Document#validate() and Document#validateSync()

---
 lib/document.js | 4 ++++
 lib/model.js    | 5 +++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 88bb7198684..6780147e915 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2066,6 +2066,7 @@ Document.prototype.isDirectSelected = function isDirectSelected(path) {
  *
  * @param {Array|String} [pathsToValidate] list of paths to validate. If set, Mongoose will validate only the modified paths that are in the given list.
  * @param {Object} [options] internal options
+ * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
  * @param {Function} [callback] optional callback called after validation completes, passing an error if one occurred
  * @return {Promise} Promise
  * @api public
@@ -2446,6 +2447,8 @@ function _handlePathsToValidate(paths, pathsToValidate) {
  *     }
  *
  * @param {Array|string} pathsToValidate only validate the given paths
+ * @param {Object} [options] options for validation
+ * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
  * @return {ValidationError|undefined} ValidationError if there are errors during validation, or undefined if there is no error.
  * @api public
  */
@@ -2627,6 +2630,7 @@ Document.prototype.$markValid = function(path) {
  * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this save operation. If not specified, defaults to the [document's associated session](api.html#document_Document-$session).
  * @param {Object} [options.safe] (DEPRECATED) overrides [schema's safe option](http://mongoosejs.com//docs/guide.html#safe). Use the `w` option instead.
  * @param {Boolean} [options.validateBeforeSave] set to false to save without validating.
+ * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
  * @param {Number|String} [options.w] set the [write concern](https://docs.mongodb.com/manual/reference/write-concern/#w-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Boolean} [options.j] set to true for MongoDB to wait until this `save()` has been [journaled before resolving the returned promise](https://docs.mongodb.com/manual/reference/write-concern/#j-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Number} [options.wtimeout] sets a [timeout for the write concern](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern).
diff --git a/lib/model.js b/lib/model.js
index 62e79dccd0c..571b751a833 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -436,6 +436,7 @@ function generateVersionError(doc, modifiedPaths) {
  * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this save operation. If not specified, defaults to the [document's associated session](api.html#document_Document-$session).
  * @param {Object} [options.safe] (DEPRECATED) overrides [schema's safe option](http://mongoosejs.com//docs/guide.html#safe). Use the `w` option instead.
  * @param {Boolean} [options.validateBeforeSave] set to false to save without validating.
+ * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
  * @param {Number|String} [options.w] set the [write concern](https://docs.mongodb.com/manual/reference/write-concern/#w-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Boolean} [options.j] set to true for MongoDB to wait until this `save()` has been [journaled before resolving the returned promise](https://docs.mongodb.com/manual/reference/write-concern/#j-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Number} [options.wtimeout] sets a [timeout for the write concern](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern).
@@ -3935,11 +3936,11 @@ Model.mapReduce = function mapReduce(o, callback) {
  * - The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).
  *
  * #### More About Aggregations:
- * 
+ *
  * - [Mongoose `Aggregate`](/docs/api/aggregate.html)
  * - [An Introduction to Mongoose Aggregate](https://masteringjs.io/tutorials/mongoose/aggregate)
  * - [MongoDB Aggregation docs](http://docs.mongodb.org/manual/applications/aggregation/)
- * 
+ *
  * @see Aggregate #aggregate_Aggregate
  * @see MongoDB http://docs.mongodb.org/manual/applications/aggregation/
  * @param {Array} [pipeline] aggregation pipeline as an array of objects

From a84d246715426a69f1e27b2d255c2b245e2734ad Mon Sep 17 00:00:00 2001
From: Tigran <tigran.contact@gmail.com>
Date: Mon, 1 Jun 2020 18:15:47 +0400
Subject: [PATCH 0926/2348] Update faq.pug

---
 docs/faq.pug | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index b36e211ac0b..96cdb97a69a 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -112,8 +112,7 @@ block content
     // Promise based alternative. `init()` returns a promise that resolves
     // when the indexes have finished building successfully. The `init()`
     // function is idempotent, so don't worry about triggering an index rebuild.
-    Model.init().then(function(err) {
-      assert.ifError(err);
+    Model.init().then(function() {
       Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
         console.log(err);
       });

From f9211b3241a92ffb1bd3b7448859f19b1156e304 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 11:13:27 -0400
Subject: [PATCH 0927/2348] test(document): repro #9080

---
 test/document.test.js | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 37b8c0f455d..b79413ca1b7 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8942,6 +8942,17 @@ describe('document', function() {
       then(doc => assert.equal(doc.item.name, 'Default Name'));
   });
 
+  it('clears cast errors when setting an array subpath (gh-9080)', function() {
+    const userSchema = new Schema({ tags: [Schema.ObjectId] });
+    const User = db.model('User', userSchema);
+
+    const user = new User({ tags: ['hey'] });
+    user.tags = [];
+
+    const err = user.validateSync();
+    assert.ifError(err);
+  });
+
   it('handles modifying a subpath of a nested array of documents (gh-8926)', function() {
     const bookSchema = new Schema({ title: String });
     const aisleSchema = new Schema({

From e70b05495f20d7aa9668646e6ee733075a1a7296 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 11:13:39 -0400
Subject: [PATCH 0928/2348] fix(document): clear nested cast errors when
 overwriting an array path

Fix #9080
---
 lib/document.js | 27 +++++++++++++++++++++++++++
 lib/model.js    |  4 ++--
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 88bb7198684..01ef8aad632 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1132,6 +1132,13 @@ Document.prototype.$set = function $set(path, val, type, options) {
     return this;
   }
 
+  // If overwriting a subdocument path, make sure to clear out
+  // any errors _before_ setting, so new errors that happen
+  // get persisted. Re: #9080
+  if (schema.$isSingleNested || schema.$isMongooseArray) {
+    _markValidSubpaths(this, path);
+  }
+
   if (schema.$isSingleNested && val != null && merge) {
     if (val instanceof Document) {
       val = val.toObject({ virtuals: false, transform: false });
@@ -2606,6 +2613,26 @@ Document.prototype.$markValid = function(path) {
   }
 };
 
+/*!
+ * ignore
+ */
+
+function _markValidSubpaths(doc, path) {
+  if (!doc.$__.validationError) {
+    return;
+  }
+
+  const keys = Object.keys(doc.$__.validationError.errors);
+  for (const key of keys) {
+    if (key.startsWith(path + '.')) {
+      delete doc.$__.validationError.errors[key];
+    }
+  }
+  if (Object.keys(doc.$__.validationError.errors).length === 0) {
+    doc.$__.validationError = null;
+  }
+}
+
 /**
  * Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`,
  * or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation **only** with the modifications to the database, it does not replace the whole document in the latter case.
diff --git a/lib/model.js b/lib/model.js
index 62e79dccd0c..1bf09b7ba90 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3935,11 +3935,11 @@ Model.mapReduce = function mapReduce(o, callback) {
  * - The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).
  *
  * #### More About Aggregations:
- * 
+ *
  * - [Mongoose `Aggregate`](/docs/api/aggregate.html)
  * - [An Introduction to Mongoose Aggregate](https://masteringjs.io/tutorials/mongoose/aggregate)
  * - [MongoDB Aggregation docs](http://docs.mongodb.org/manual/applications/aggregation/)
- * 
+ *
  * @see Aggregate #aggregate_Aggregate
  * @see MongoDB http://docs.mongodb.org/manual/applications/aggregation/
  * @param {Array} [pipeline] aggregation pipeline as an array of objects

From 863490b33337ccededa331451ce7f46b99b1627e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 11:42:20 -0400
Subject: [PATCH 0929/2348] test(document): repro #9011

---
 test/document.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index b79413ca1b7..1d9dac4005e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8953,6 +8953,30 @@ describe('document', function() {
     assert.ifError(err);
   });
 
+  it('saves successfully if you splice() a sliced array (gh-9011)', function() {
+    const childSchema = Schema({ values: [Number] });
+    const parentSchema = Schema({ children: [childSchema] });
+
+    const Parent = db.model('Parent', parentSchema);
+
+    return co(function*() {
+      yield Parent.create({
+        children: [
+          { values: [1, 2, 3] },
+          { values: [4, 5, 6] }
+        ]
+      });
+
+      const parent = yield Parent.findOne();
+      const copy = parent.children[0].values.slice();
+      copy.splice(1);
+
+      yield parent.save();
+      const _parent = yield Parent.findOne();
+      assert.deepEqual(_parent.toObject().children[0].values, [1, 2, 3]);
+    });
+  });
+
   it('handles modifying a subpath of a nested array of documents (gh-8926)', function() {
     const bookSchema = new Schema({ title: String });
     const aisleSchema = new Schema({

From 421776ccfb9d24648f457a620732cd7e6f38d23e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 11:42:30 -0400
Subject: [PATCH 0930/2348] fix(document): avoid tracking changes like
 `splice()` on slice()-ed arrays

Fix #9011
---
 lib/types/core_array.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index c4c6b33b441..29f03859d81 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -15,6 +15,7 @@ const arrayParentSymbol = require('../helpers/symbols').arrayParentSymbol;
 const arrayPathSymbol = require('../helpers/symbols').arrayPathSymbol;
 const arraySchemaSymbol = require('../helpers/symbols').arraySchemaSymbol;
 const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
+const slicedSymbol = Symbol('mongoose#Array#sliced');
 
 const _basePush = Array.prototype.push;
 
@@ -321,6 +322,9 @@ class CoreMongooseArray extends Array {
    */
 
   _registerAtomic(op, val) {
+    if (this[slicedSymbol]) {
+      return;
+    }
     if (op === '$set') {
       // $set takes precedence over all other ops.
       // mark entire array modified.
@@ -839,6 +843,7 @@ class CoreMongooseArray extends Array {
     ret[arrayParentSymbol] = this[arrayParentSymbol];
     ret[arraySchemaSymbol] = this[arraySchemaSymbol];
     ret[arrayAtomicsSymbol] = this[arrayAtomicsSymbol];
+    ret[slicedSymbol] = true;
     return ret;
   }
 

From c52ce6c4b747b5b85b8804c519733e08f4946865 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 12:58:22 -0400
Subject: [PATCH 0931/2348] test(populate): repro #9073

---
 test/model.populate.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5d268e0ce43..17f15b29d8c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9408,4 +9408,25 @@ describe('model: populate:', function() {
       assert.equal(res.teams[0].members[0].user.name, 'User');
     });
   });
+
+  it('no-op if populating a nested path (gh-9073)', function() {  
+    const buildingSchema = Schema({ owner: String });
+    const Building = db.model('Building', buildingSchema);
+  
+    const officeSchema = new Schema({
+      title: String,
+      place: { building: { type: Schema.ObjectId, ref: 'Building' } }
+    });
+    const Office = db.model('Office', officeSchema);
+
+    return co(function*() {
+      const building = new Building({ owner: 'test' });
+      yield building.save();
+      yield Office.create({ place: { building: building._id } });
+
+      const foundOffice = yield Office.findOne({}).
+        populate({ path: 'place', populate: 'building' });
+      assert.equal(foundOffice.place.building.owner, 'test');
+    });
+  });
 });

From ec8e87e753437d8c2dc949ddca9657649e6c9e28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 13:19:50 -0400
Subject: [PATCH 0932/2348] fix(populate): make populating a nested path a
 no-op

Fix #9073
---
 lib/helpers/populate/getModelsMapForPopulate.js | 5 +++++
 lib/model.js                                    | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 4853921cf69..b012f4e7cdd 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -50,6 +50,11 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         schema.options.refPath == null) {
       continue;
     }
+    // Populating a nested path should always be a no-op re: #9073.
+    // People shouldn't do this, but apparently they do.
+    if (modelSchema.nested[options.path]) {
+      continue;
+    }
     const isUnderneathDocArray = schema && schema.$isUnderneathDocArray;
     if (isUnderneathDocArray && get(options, 'options.sort') != null) {
       return new MongooseError('Cannot populate with `sort` on path ' + options.path +
diff --git a/lib/model.js b/lib/model.js
index 1bf09b7ba90..7371c6d38e2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4428,7 +4428,7 @@ function populate(model, docs, options, callback) {
     // If no models to populate but we have a nested populate,
     // keep trying, re: gh-8946
     if (options.populate != null) {
-      const opts = options.populate.map(pop => Object.assign({}, pop, {
+      const opts = utils.populate(options.populate).map(pop => Object.assign({}, pop, {
         path: options.path + '.' + pop.path
       }));
       return model.populate(docs, opts, callback);

From 6cb1c92447f18e60dae55119c2635e2311b3fd7f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 13:25:33 -0400
Subject: [PATCH 0933/2348] style: fix lint

---
 test/model.populate.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 17f15b29d8c..6f8e07899f6 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9409,10 +9409,10 @@ describe('model: populate:', function() {
     });
   });
 
-  it('no-op if populating a nested path (gh-9073)', function() {  
+  it('no-op if populating a nested path (gh-9073)', function() {
     const buildingSchema = Schema({ owner: String });
     const Building = db.model('Building', buildingSchema);
-  
+
     const officeSchema = new Schema({
       title: String,
       place: { building: { type: Schema.ObjectId, ref: 'Building' } }

From e45786fa3e3bf793b8b94d092f382167bf013ac4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Jun 2020 16:25:56 -0400
Subject: [PATCH 0934/2348] chore: release 5.9.17

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 4ed61986e42..c26b25c6b0f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.9.17 / 2020-06-02
+===================
+ * fix(document): avoid tracking changes like `splice()` on slice()-ed arrays #9011
+ * fix(populate): make populating a nested path a no-op #9073
+ * fix(document): clear nested cast errors when overwriting an array path #9080
+ * fix: upgrade mongodb to v3.5.8 #9069 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(document): add validateModifiedOnly to Document#save(), Document#validateSync() and Document#validate() #9078 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(faq): fix typo #9075 [tigransimonyan](https://github.com/tigransimonyan)
+ * docs: document all parameters to .debug #9029 [dandv](https://github.com/dandv)
+ * docs: fix property value in Getters example #9061 [ismet](https://github.com/ismet)
+
 5.9.16 / 2020-05-25
 ===================
  * perf(error): convert errors to classes extending Error for lower CPU overhead #9021 [zbjornson](https://github.com/zbjornson)
diff --git a/package.json b/package.json
index 8e9291dddc3..a4a12abf53d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.16",
+  "version": "5.9.17",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 09e66ed1ab1664bb0d3c428530e1ef498bb8f29a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Jun 2020 12:36:05 -0400
Subject: [PATCH 0935/2348] docs(geojson): add notes about geojson 2dsphere
 indexes

Fix #9044
---
 docs/geojson.pug                   | 21 +++++++++++++
 lib/schema/operators/geospatial.js |  5 ++++
 test/geojson.test.js               | 47 ++++++++++++++++++++++++++++++
 3 files changed, 73 insertions(+)

diff --git a/docs/geojson.pug b/docs/geojson.pug
index f8683d3899d..a2f7d58593c 100644
--- a/docs/geojson.pug
+++ b/docs/geojson.pug
@@ -145,3 +145,24 @@ block content
     ```javascript
     [require:geojson.*within helper]
     ```
+
+    <h2 id="geospatial-indexes">Geospatial Indexes</h2>
+
+    MongoDB supports [2dsphere indexes](https://docs.mongodb.com/manual/core/2dsphere/)
+    for speeding up geospatial queries. Here's how you can define
+    a 2dsphere index on a GeoJSON point:
+
+    ```javascript
+    [require:geojson.*index$]
+    ```
+
+    You can also define a geospatial index using the [`Schema#index()` function](/docs/api/schema.html#schema_Schema-index)
+    as shown below.
+
+    ```javascript
+    citySchema.index({ location: '2dsphere' });
+    ```
+
+    MongoDB's [`$near` query operator](https://docs.mongodb.com/v4.0/reference/operator/query/near/#op._S_near)
+    and [`$geoNear` aggregation stage](https://docs.mongodb.com/manual/reference/operator/aggregation/geoNear/#pipe._S_geoNear)
+    _require_ a 2dsphere index. 
diff --git a/lib/schema/operators/geospatial.js b/lib/schema/operators/geospatial.js
index 73e38f81c9c..80a60520713 100644
--- a/lib/schema/operators/geospatial.js
+++ b/lib/schema/operators/geospatial.js
@@ -29,6 +29,11 @@ function cast$near(val) {
     return cast$geometry(val, this);
   }
 
+  if (!Array.isArray(val)) {
+    throw new TypeError('$near must be either an array or an object ' +
+      'with a $geometry property');
+  }
+
   return SchemaArray.prototype.castForQuery.call(this, val);
 }
 
diff --git a/test/geojson.test.js b/test/geojson.test.js
index 36aa46df4e3..f99e3f72f23 100644
--- a/test/geojson.test.js
+++ b/test/geojson.test.js
@@ -90,4 +90,51 @@ describe('geojson', function() {
       then(() => City.findOne().where('location').within(colorado)).
       then(doc => assert.equal(doc.name, 'Denver'));
   });
+
+  it('index', function() {
+    const denver = { type: 'Point', coordinates: [-104.9903, 39.7392] };
+    const City = db.model('City', new Schema({
+      name: String,
+      location: {
+        type: pointSchema,
+        index: '2dsphere' // Create a special 2dsphere index on `City.location`
+      }
+    }));
+    // acquit:ignore:start
+    const colorado = {
+      type: 'Polygon',
+      coordinates: [[
+        [-109, 41],
+        [-102, 41],
+        [-102, 37],
+        [-109, 37],
+        [-109, 41]
+      ]]
+    };
+    // acquit:ignore:end
+
+    return City.create({ name: 'Denver', location: denver }).
+      then(() => City.findOne().where('location').within(colorado)).
+      then(doc => assert.equal(doc.name, 'Denver'));
+  });
+
+  it('near', function() {
+    const denver = { type: 'Point', coordinates: [-104.9903, 39.7392] };
+    const City = db.model('City', new Schema({
+      name: String,
+      location: {
+        type: pointSchema,
+        index: '2dsphere' // Create a special 2dsphere index on `City.location`
+      }
+    }));
+
+    // "Garden of the Gods" in Colorado
+    const $geometry = { type: 'Point', coordinates: [-104.8719443, 38.8783536] };
+
+    return City.create({ name: 'Denver', location: denver }).
+      // Without a 2dsphere index, this will error out with:
+      // 'unable to find index for $geoNear query"
+      then(() => City.findOne({ location: { $near: { $geometry } } })).
+      then(doc => assert.equal(doc.name, 'Denver'));
+  });
 });

From f168f17526fc2e468313ca2d857e5452f6c05031 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Jun 2020 16:25:13 -0400
Subject: [PATCH 0936/2348] fix(query): make `setDefaultsOnInsert` a mongoose
 option so it doesn't end up in debug output

Fix #9086
---
 lib/query.js | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index de1686e703c..dbdd0f2ce8a 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1357,6 +1357,10 @@ Query.prototype.setOptions = function(options, overwrite) {
     this._mongooseOptions.omitUndefined = options.omitUndefined;
     delete options.omitUndefined;
   }
+  if ('setDefaultsOnInsert' in options) {
+    this._mongooseOptions.setDefaultsOnInsert = options.setDefaultsOnInsert;
+    delete options.setDefaultsOnInsert;
+  }
 
   return Query.base.setOptions.call(this, options);
 };
@@ -3486,7 +3490,10 @@ Query.prototype._findAndModify = function(type, callback) {
 
     if (!isOverwriting) {
       this._update = castDoc(this, opts.overwrite);
-      this._update = setDefaultsOnInsert(this._conditions, schema, this._update, opts);
+      const _opts = Object.assign({}, opts, {
+        setDefaultsOnInsert: this._mongooseOptions.setDefaultsOnInsert
+      });
+      this._update = setDefaultsOnInsert(this._conditions, schema, this._update, _opts);
       if (!this._update || Object.keys(this._update).length === 0) {
         if (opts.upsert) {
           // still need to do the upsert to empty doc
@@ -3737,8 +3744,11 @@ function _updateThunk(op, callback) {
       return null;
     }
 
+    const _opts = Object.assign({}, options, {
+      setDefaultsOnInsert: this._mongooseOptions.setDefaultsOnInsert
+    });
     this._update = setDefaultsOnInsert(this._conditions, this.model.schema,
-      this._update, options);
+      this._update, _opts);
   }
 
   const runValidators = _getOption(this, 'runValidators', false);

From b2e623ca0b8a5b2dfc6220f6d6eb1882e245bc4d Mon Sep 17 00:00:00 2001
From: Elvis Sarfo Antwi <sarfoantwielvis@gmail.com>
Date: Thu, 4 Jun 2020 03:38:36 +0000
Subject: [PATCH 0937/2348] Corrected a typo in a code snippet.

The variable name "Schema" was changed to "schema". This will solve the issue of getting undefined who you call schema as it has been than in the snippet
---
 docs/api/mongoose.html | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/api/mongoose.html b/docs/api/mongoose.html
index f48284709bf..0574af4bcb3 100644
--- a/docs/api/mongoose.html
+++ b/docs/api/mongoose.html
@@ -186,7 +186,7 @@ <h4>Example:</h4>
 <pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
 
 <span class="hljs-comment">// define an Actor model with this mongoose instance</span>
-<span class="hljs-keyword">const</span> Schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
+<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
 mongoose.model(<span class="hljs-string">'Actor'</span>, schema);
 
 <span class="hljs-comment">// create a new connection</span>
@@ -314,4 +314,4 @@ <h4>Example</h4>
       }
   };
 
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
+}(this, this.document));</script></div></body></html>

From c2ed8c121a371e788f94b2d7193a6d62c1c616a0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Jun 2020 13:24:10 -0400
Subject: [PATCH 0938/2348] docs: add link to edit on GitHub for top-level
 tutorials

Re: #9058
---
 docs/async-await.pug         |  4 ++++
 docs/browser.pug             |  4 ++++
 docs/built-with-mongoose.pug |  4 ++++
 docs/compatibility.pug       |  4 ++++
 docs/connections.pug         |  4 ++++
 docs/css/mongoose5.css       | 18 ++++++++++++++++++
 docs/deprecations.pug        |  4 ++++
 docs/documents.pug           |  4 ++++
 docs/faq.pug                 |  4 ++++
 docs/further_reading.pug     |  4 ++++
 docs/geojson.pug             |  4 ++++
 docs/guide.pug               |  4 ++++
 docs/guides.pug              |  4 ++++
 docs/images/pencil.svg       |  5 +++++
 docs/jest.pug                |  4 ++++
 docs/lambda.pug              |  4 ++++
 docs/middleware.pug          |  4 ++++
 docs/migration.pug           |  4 ++++
 docs/models.pug              |  4 ++++
 docs/plugins.pug             |  4 ++++
 docs/populate.pug            |  4 ++++
 docs/queries.pug             |  4 ++++
 docs/schematypes.pug         |  4 ++++
 docs/subdocs.pug             |  4 ++++
 docs/transactions.pug        |  4 ++++
 website.js                   |  2 ++
 26 files changed, 117 insertions(+)
 create mode 100644 docs/images/pencil.svg

diff --git a/docs/async-await.pug b/docs/async-await.pug
index 8663304de07..1f8a588d3a8 100644
--- a/docs/async-await.pug
+++ b/docs/async-await.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Async/Await
 
diff --git a/docs/browser.pug b/docs/browser.pug
index a2b4b97542b..eedd9217bab 100644
--- a/docs/browser.pug
+++ b/docs/browser.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     <h1>Mongoose in the Browser</h1>
 
diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
index dbc48511c0b..e6a76d956d5 100644
--- a/docs/built-with-mongoose.pug
+++ b/docs/built-with-mongoose.pug
@@ -1,6 +1,10 @@
 extends layout
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Built With Mongoose
 
diff --git a/docs/compatibility.pug b/docs/compatibility.pug
index 7f5a84ef6d4..085fafb9f70 100644
--- a/docs/compatibility.pug
+++ b/docs/compatibility.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## MongoDB Server Version Compatibility
 
diff --git a/docs/connections.pug b/docs/connections.pug
index 7bf730cbdc0..930ef08fa00 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     <h2><a href="#connections">Connections</a></h2>
 
diff --git a/docs/css/mongoose5.css b/docs/css/mongoose5.css
index c909e6df7ce..fcf94338f15 100644
--- a/docs/css/mongoose5.css
+++ b/docs/css/mongoose5.css
@@ -177,6 +177,20 @@ pre {
   margin-top: 5px;
 }
 
+.edit-docs-link {
+  position: absolute;
+  top: 0.125em;
+  right: 0px;
+  background-color: #dfdfdf;
+  padding: 5px;
+  padding-bottom: 0px;
+  border-radius: 3px;
+}
+
+.edit-docs-link img {
+  width: 1.25em;
+}
+
 /* Mobile */
 
 #mobile-menu {
@@ -280,6 +294,10 @@ pre {
   .active {
     display: block !important;
   }
+
+  .edit-docs-link {
+    display: none;
+  }
 }
 
 .pure-menu-item:last-of-type {
diff --git a/docs/deprecations.pug b/docs/deprecations.pug
index 4c53a85c91f..7c0c0dff005 100644
--- a/docs/deprecations.pug
+++ b/docs/deprecations.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Deprecation Warnings
 
diff --git a/docs/documents.pug b/docs/documents.pug
index a2ddd4e3bed..1a7c89c058e 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Documents
 
diff --git a/docs/faq.pug b/docs/faq.pug
index 96cdb97a69a..b36fce37bf6 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -17,6 +17,10 @@ block append style
     }
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## FAQ
 
diff --git a/docs/further_reading.pug b/docs/further_reading.pug
index 49259c70fd5..3fff2b60490 100644
--- a/docs/further_reading.pug
+++ b/docs/further_reading.pug
@@ -21,6 +21,10 @@ append style
     }
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Further Reading
 
diff --git a/docs/geojson.pug b/docs/geojson.pug
index a2f7d58593c..2236b081a21 100644
--- a/docs/geojson.pug
+++ b/docs/geojson.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     # Using GeoJSON
 
diff --git a/docs/guide.pug b/docs/guide.pug
index 5f9b9f59335..389be5cb92f 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Schemas
 
diff --git a/docs/guides.pug b/docs/guides.pug
index 3118e771281..f77256a4277 100644
--- a/docs/guides.pug
+++ b/docs/guides.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Guides
 
diff --git a/docs/images/pencil.svg b/docs/images/pencil.svg
new file mode 100644
index 00000000000..368b2eb107d
--- /dev/null
+++ b/docs/images/pencil.svg
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" viewBox="0 0 1000 1000" enable-background="new 0 0 1000 1000" xml:space="preserve">
+<g><g transform="matrix(1 0 0 -1 0 480)"><path stroke="#0971B2" fill="#0971B2" d="M930.9,420.5c-33.1,31.8-69.3,47.7-108.7,47.7c-44.5,0-83.9-17.2-118.2-51.5L99.4-185.9c-3.8-3.8-6.4-8.9-7.6-15.3c-2.5-8.9-29.2-97.9-80.1-267c-3.8-12.7-1.3-23.5,7.6-32.4c6.4-5.1,14-7.6,22.9-7.6h9.5c132.2,44.5,219.9,73.1,263.2,85.8c3.8,1.3,7.6,3.8,11.4,7.6c375,370,577.2,570.2,606.4,600.7c38.1,39.4,57.2,79.5,57.2,120.1C988.7,346.8,969,384.9,930.9,420.5z M694.4,319.4c31.8-7.6,61.7-25.4,89.6-53.4c26.7-26.7,43.2-57.2,49.6-91.5C747.2,88.1,578.7-79.1,328.3-327c-12.7,30.5-29.9,56.6-51.5,78.2c-26.7,26.7-56.6,47-89.6,61L332.1-42.9l210.7,210.7L694.4,319.4z M145.2-239.3c31.8-7.6,61-25.4,87.7-53.4c21.6-21.6,36.9-47,45.8-76.3c-12.7-3.8-42.9-14-90.6-30.5c-47.7-16.5-82.3-28-103.9-34.3c6.4,19.1,16.8,52.1,31.5,99.2C130.3-287.6,140.1-255.8,145.2-239.3z M888.9,229.8l-5.7-5.7c-12.7,33.1-31.1,61.7-55.3,85.8C802.5,335.3,774.5,355,744,369l1.9,1.9l1.9,1.9c22.9,22.9,47.7,34.3,74.4,34.3c22.9,0,45.1-10.8,66.7-32.4c25.4-24.2,38.1-47.7,38.1-70.6S914.4,256.5,888.9,229.8z"/></g></g>
+</svg>
\ No newline at end of file
diff --git a/docs/jest.pug b/docs/jest.pug
index cb07e5f7353..2cb80547c36 100644
--- a/docs/jest.pug
+++ b/docs/jest.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     # Testing Mongoose with [Jest](https://www.npmjs.com/package/jest)
 
diff --git a/docs/lambda.pug b/docs/lambda.pug
index 136e811c5ab..29123a9f96b 100644
--- a/docs/lambda.pug
+++ b/docs/lambda.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   h2 Using Mongoose With AWS Lambda
   :markdown
     <script>
diff --git a/docs/middleware.pug b/docs/middleware.pug
index 8122dec1eca..d0eaead34c7 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Middleware
 
diff --git a/docs/migration.pug b/docs/migration.pug
index 536377d9488..eaca733d94e 100644
--- a/docs/migration.pug
+++ b/docs/migration.pug
@@ -7,6 +7,10 @@ block append style
     }
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   h2 Migrating from 3.x to 4.x
   :markdown
     There are several [backwards-breaking changes](https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes) to be aware of when migrating from Mongoose 3 to Mongoose 4.
diff --git a/docs/models.pug b/docs/models.pug
index 2851dc51e78..f3cd5e8540f 100644
--- a/docs/models.pug
+++ b/docs/models.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Models
 
diff --git a/docs/plugins.pug b/docs/plugins.pug
index 58327091485..17b4149865b 100644
--- a/docs/plugins.pug
+++ b/docs/plugins.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Plugins
 
diff --git a/docs/populate.pug b/docs/populate.pug
index da0c609b11c..3eecdd5d6cd 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Populate
 
diff --git a/docs/queries.pug b/docs/queries.pug
index ceaa5010d7c..05a813c85d6 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Queries
 
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 410e2992001..0e345936718 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     <h2 id="schematypes"><a href="#schematypes">SchemaTypes</a></h2>
 
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index d489aa4b68a..78588429573 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -5,6 +5,10 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     ## Subdocuments
 
diff --git a/docs/transactions.pug b/docs/transactions.pug
index 74b2056a5b9..b6762f439a0 100644
--- a/docs/transactions.pug
+++ b/docs/transactions.pug
@@ -5,6 +5,10 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   :markdown
     # Transactions in Mongoose
 
diff --git a/website.js b/website.js
index 0b616705160..806e0633447 100644
--- a/website.js
+++ b/website.js
@@ -98,6 +98,8 @@ function pugify(filename, options, newfile) {
   options.linktype = linktype;
   options.href = href;
   options.klass = klass;
+  options.editLink = 'https://github.com/Automattic/mongoose/blob/master' +
+    filename.replace(process.cwd(), '');
 
   let contents = fs.readFileSync(filename).toString();
 

From 01fbdc77b08ffc508d761be891d56c33ef10bbfd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Jun 2020 14:20:38 -0400
Subject: [PATCH 0939/2348] docs: add edit link icon to tutorials

Re: #9058
---
 docs/css/mongoose5.css  | 3 ++-
 docs/tutorials/index.js | 2 +-
 website.js              | 3 +++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/docs/css/mongoose5.css b/docs/css/mongoose5.css
index fcf94338f15..bca1b346366 100644
--- a/docs/css/mongoose5.css
+++ b/docs/css/mongoose5.css
@@ -181,7 +181,8 @@ pre {
   position: absolute;
   top: 0.125em;
   right: 0px;
-  background-color: #dfdfdf;
+  background-color: #fafafa;
+  border: 1px solid #ddd;
   padding: 5px;
   padding-bottom: 0px;
   border-radius: 3px;
diff --git a/docs/tutorials/index.js b/docs/tutorials/index.js
index b14eccff734..3c7546eb2da 100644
--- a/docs/tutorials/index.js
+++ b/docs/tutorials/index.js
@@ -3,7 +3,7 @@
 const fs = require('fs');
 
 const tutorials = fs.readdirSync(__dirname).filter(file => file.endsWith('.md'));
-console.log(tutorials)
+
 module.exports = tutorials.reduce((map, filename) => {
   const content = fs.readFileSync(`${__dirname}/${filename}`, 'utf8');
   map[`docs/tutorials/${filename}`] = {
diff --git a/website.js b/website.js
index 806e0633447..d4e6f3242b0 100644
--- a/website.js
+++ b/website.js
@@ -76,6 +76,9 @@ append style
     p { line-height: 1.5em }
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
   :markdown
 ${md.split('\n').map(line => '    ' + line).join('\n')}
 `;

From 9798d228f9aea963aea0898b5c3529ed881b1d5b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Jun 2020 14:41:03 -0400
Subject: [PATCH 0940/2348] docs: add edit link to acquit-only tutorials

Re: #9058
---
 docs/acquit.pug       | 4 ++++
 docs/source/acquit.js | 1 +
 website.js            | 6 +++++-
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/docs/acquit.pug b/docs/acquit.pug
index 83ae127de64..6997a9aade9 100644
--- a/docs/acquit.pug
+++ b/docs/acquit.pug
@@ -1,6 +1,10 @@
 extends layout
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
   ul.toc
     each block in acquitBlocks[0].blocks
       li
diff --git a/docs/source/acquit.js b/docs/source/acquit.js
index ad378070642..a516cb0c612 100644
--- a/docs/source/acquit.js
+++ b/docs/source/acquit.js
@@ -84,6 +84,7 @@ files.forEach(function(file) {
   }
 
   exports[file.output] = {
+    input: file.input,
     title: file.title,
     acquitBlocks: blocks,
     suffix: file.suffix,
diff --git a/website.js b/website.js
index d4e6f3242b0..9064361a6e1 100644
--- a/website.js
+++ b/website.js
@@ -101,8 +101,10 @@ function pugify(filename, options, newfile) {
   options.linktype = linktype;
   options.href = href;
   options.klass = klass;
-  options.editLink = 'https://github.com/Automattic/mongoose/blob/master' +
+
+  const _editLink = 'https://github.com/Automattic/mongoose/blob/master' +
     filename.replace(process.cwd(), '');
+  options.editLink = options.editLink || _editLink;
 
   let contents = fs.readFileSync(filename).toString();
 
@@ -163,5 +165,7 @@ const _acquit = require('./docs/source/acquit');
 const acquitFiles = Object.keys(_acquit);
 acquitFiles.forEach(function(file) {
   const filename = __dirname + '/docs/acquit.pug';
+  _acquit[file].editLink = 'https://github.com/Automattic/mongoose/blob/master/' +
+    _acquit[file].input.replace(process.cwd(), '');
   pugify(filename, _acquit[file], __dirname + '/docs/' + file);
 });

From 67a7be1f4aefe6d45a670cf2de8c57a32ece973f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Jun 2020 15:11:16 -0400
Subject: [PATCH 0941/2348] docs: add edit link for all API docs

Fix #9058
---
 docs/api.pug       | 10 +++++++---
 docs/api_split.pug |  3 +++
 docs/css/api.css   |  4 ++++
 docs/source/api.js |  4 ++++
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/docs/api.pug b/docs/api.pug
index 7644708ca4f..56c300cda1b 100644
--- a/docs/api.pug
+++ b/docs/api.pug
@@ -29,9 +29,13 @@ block content
 
   each item in docs
     hr.separate-api
-    h2(id=item.name, class="item-header")
-      a(href='#' + item.name)
-        | #{item.name}
+    div.item-header-wrap
+      <a class="edit-docs-link" href="#{item.editLink}">
+        <img src="/docs/images/pencil.svg" />
+      </a>
+      h2(id=item.name, class="item-header")
+        a(href='#' + item.name)
+          | #{item.name}
     ul
       each prop in item.props
         li
diff --git a/docs/api_split.pug b/docs/api_split.pug
index 021ca601bd6..83f8b6ac074 100644
--- a/docs/api_split.pug
+++ b/docs/api_split.pug
@@ -15,6 +15,9 @@ append style
     }
 
 block content
+  <a class="edit-docs-link" href="#{editLink}">
+    <img src="/docs/images/pencil.svg" />
+  </a>
   h1 #{name}
 
   div.
diff --git a/docs/css/api.css b/docs/css/api.css
index ca1b7a3babb..0c529fe038e 100644
--- a/docs/css/api.css
+++ b/docs/css/api.css
@@ -42,6 +42,10 @@
   list-style-type: none;
 }
 
+.item-header-wrap {
+  position: relative;
+}
+
 @media (max-width: 1785px) {
   .api-nav {
     display: none;
diff --git a/docs/source/api.js b/docs/source/api.js
index 2fdf9c4e352..0f78017e634 100644
--- a/docs/source/api.js
+++ b/docs/source/api.js
@@ -182,6 +182,10 @@ function parse() {
       data.hideFromNav = true;
     }
 
+    data.file = props.file;
+    data.editLink = 'https://github.com/Automattic/mongoose/blob/master/' +
+      props.file;
+
     out.push(data);
   }
 }

From b73cb618ace5e75195422ca359c2e39eca68476b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Jun 2020 16:34:06 -0400
Subject: [PATCH 0942/2348] docs: make active page bold in navbar

Fix #9062
---
 docs/css/mongoose5.css |  4 +++
 docs/layout.pug        | 58 +++++++++++++++++++++---------------------
 docs/splitApiDocs.js   |  3 ++-
 website.js             |  5 ++--
 4 files changed, 38 insertions(+), 32 deletions(-)

diff --git a/docs/css/mongoose5.css b/docs/css/mongoose5.css
index bca1b346366..3a20d714d83 100644
--- a/docs/css/mongoose5.css
+++ b/docs/css/mongoose5.css
@@ -192,6 +192,10 @@ pre {
   width: 1.25em;
 }
 
+.pure-menu-link.selected {
+  font-weight: bold;
+}
+
 /* Mobile */
 
 #mobile-menu {
diff --git a/docs/layout.pug b/docs/layout.pug
index 874802463d4..0a6293e7271 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -60,63 +60,63 @@ html(lang='en')
                 button#search-button-nav
                   img(src="/docs/images/search.svg")
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/index.html") Quick Start
+                a.pure-menu-link(href="/docs/index.html", class=outputUrl === '/docs/index.html' ? 'selected' : '') Quick Start
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/guides.html") Guides
+                a.pure-menu-link(href="/docs/guides.html", class=outputUrl === '/docs/guides.html' ? 'selected' : '') Guides
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/guide.html") Schemas
+                a.pure-menu-link(href="/docs/guide.html", class=outputUrl === '/docs/schemas.html' ? 'selected' : '') Schemas
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/schematypes.html") SchemaTypes
+                a.pure-menu-link(href="/docs/schematypes.html", class=outputUrl === '/docs/schematypes.html' ? 'selected' : '') SchemaTypes
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/connections.html") Connections
+                a.pure-menu-link(href="/docs/connections.html", class=outputUrl === '/docs/connections.html' ? 'selected' : '') Connections
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/models.html") Models
+                a.pure-menu-link(href="/docs/models.html", class=outputUrl === '/docs/models.html' ? 'selected' : '') Models
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/documents.html") Documents
+                a.pure-menu-link(href="/docs/documents.html", class=outputUrl === '/docs/documents.html' ? 'selected' : '') Documents
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/subdocs.html") Subdocuments
+                a.pure-menu-link(href="/docs/subdocs.html", class=outputUrl === '/docs/subdocs.html' ? 'selected' : '') Subdocuments
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/queries.html") Queries
+                a.pure-menu-link(href="/docs/queries.html", class=outputUrl === '/docs/queries.html' ? 'selected' : '') Queries
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/validation.html") Validation
+                a.pure-menu-link(href="/docs/validation.html", class=outputUrl === '/docs/validation.html' ? 'selected' : '') Validation
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/middleware.html") Middleware
+                a.pure-menu-link(href="/docs/middleware.html", class=outputUrl === '/docs/middleware.html' ? 'selected' : '') Middleware
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/populate.html") Populate
+                a.pure-menu-link(href="/docs/populate.html", class=outputUrl === '/docs/populate.html' ? 'selected' : '') Populate
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/discriminators.html") Discriminators
+                a.pure-menu-link(href="/docs/discriminators.html", class=outputUrl === '/docs/discriminators.html' ? 'selected' : '') Discriminators
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/plugins.html") Plugins
+                a.pure-menu-link(href="/docs/plugins.html", class=outputUrl === '/docs/plugins.html' ? 'selected' : '') Plugins
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/api.html") API
+                a.pure-menu-link(href="/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/mongoose.html") Mongoose
+                a.pure-menu-link(href="/docs/api/mongoose.html", class=outputUrl === '/docs/api/mongoose.html' ? 'selected' : '') Mongoose
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/schema.html") Schema
+                a.pure-menu-link(href="/docs/api/schema.html", class=outputUrl === '/docs/api/schema.html' ? 'selected' : '') Schema
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/connection.html") Connection
+                a.pure-menu-link(href="/docs/api/connection.html", class=outputUrl === '/docs/api/connection.html' ? 'selected' : '') Connection
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/document.html") Document
+                a.pure-menu-link(href="/docs/api/document.html", class=outputUrl === '/docs/api/document.html' ? 'selected' : '') Document
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/model.html") Model
+                a.pure-menu-link(href="/docs/api/model.html", class=outputUrl === '/docs/api/model.html' ? 'selected' : '') Model
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/query.html") Query
+                a.pure-menu-link(href="/docs/api/query.html", class=outputUrl === '/docs/api/query.html' ? 'selected' : '') Query
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/aggregate.html") Aggregate
+                a.pure-menu-link(href="/docs/api/aggregate.html", class=outputUrl === '/docs/api/aggregate.html' ? 'selected' : '') Aggregate
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/schematype.html") SchemaType
+                a.pure-menu-link(href="/docs/api/schematype.html", class=outputUrl === '/docs/api/schematype.html' ? 'selected' : '') SchemaType
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/virtualtype.html") VirtualType
+                a.pure-menu-link(href="/docs/api/virtualtype.html", class=outputUrl === '/docs/api/virtualtype.html' ? 'selected' : '') VirtualType
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/compatibility.html") Version Compatibility
+                a.pure-menu-link(href="/docs/compatibility.html", class=outputUrl === '/docs/compatibility.html' ? 'selected' : '') Version Compatibility
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/faq.html") FAQ
+                a.pure-menu-link(href="/docs/faq.html", class=outputUrl === '/docs/faq.html' ? 'selected' : '') FAQ
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/further_reading.html") Further Reading
+                a.pure-menu-link(href="/docs/further_reading.html", class=outputUrl === '/docs/further_reading.html' ? 'selected' : '') Further Reading
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/enterprise.html") For Enterprise
+                a.pure-menu-link(href="/docs/enterprise.html", class=outputUrl === '/docs/enterprise.html' ? 'selected' : '') For Enterprise
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/built-with-mongoose.html") Built with Mongoose
+                a.pure-menu-link(href="/docs/built-with-mongoose.html", , class=outputUrl === '/docs/built-with-mongoose.html' ? 'selected' : '') Built with Mongoose
             div.cpc-ad
               <script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script>
         .container
diff --git a/docs/splitApiDocs.js b/docs/splitApiDocs.js
index 46e2f8ee8f4..7b7875a726c 100644
--- a/docs/splitApiDocs.js
+++ b/docs/splitApiDocs.js
@@ -12,7 +12,8 @@ api.docs.forEach(file => {
 
   const options = Object.assign({}, file, {
     package: pkg,
-    docs: api.docs
+    docs: api.docs,
+    outputUrl: `/docs/api/${file.name.toLowerCase()}.html`
   });
 
   const html = jade.renderFile('./docs/api_split.pug', options);
diff --git a/website.js b/website.js
index 9064361a6e1..617859f924e 100644
--- a/website.js
+++ b/website.js
@@ -130,14 +130,15 @@ function pugify(filename, options, newfile) {
     }
   };
 
+  newfile = newfile || filename.replace('.pug', '.html');
+  options.outputUrl = newfile.replace(process.cwd(), '');
+
   pug.render(contents, options, function(err, str) {
     if (err) {
       console.error(err.stack);
       return;
     }
 
-    newfile = newfile || filename.replace('.pug', '.html');
-
     fs.writeFile(newfile, str, function(err) {
       if (err) {
         console.error('could not write', err.stack);

From 278a13cd4510522fca648f62deb35c319dd4c87c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Jun 2020 16:54:58 -0400
Subject: [PATCH 0943/2348] docs(connection+index): add
 serverSelectionTimeoutMS and heartbeatFrequencyMS to `connect()` and
 `openUri()` options

Fix #9071
---
 lib/connection.js | 5 ++++-
 lib/index.js      | 6 ++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 12f0517aa06..c64e192c1f9 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -541,9 +541,12 @@ Connection.prototype.onOpen = function() {
  * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.
+ * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
+ * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to opt in to the MongoDB driver's replica set and sharded cluster monitoring engine.
+ * @param {Number} [options.serverSelectionTimeoutMS] If `useUnifiedTopology = true`, the MongoDB driver will try to find a server to send any given operation to, and keep retrying for `serverSelectionTimeoutMS` milliseconds before erroring out. If not set, the MongoDB driver defaults to using `30000` (30 seconds).
+ * @param {Number} [options.heartbeatFrequencyMS] If `useUnifiedTopology = true`, the MongoDB driver sends a heartbeat every `heartbeatFrequencyMS` to check on the status of the connection. A heartbeat is subject to `serverSelectionTimeoutMS`, so the MongoDB driver will retry failed heartbeats for up to 30 seconds by default. Mongoose only emits a `'disconnected'` event after a heartbeat has failed, so you may want to decrease this setting to reduce the time between when your server goes down and when Mongoose emits `'disconnected'`. We recommend you do **not** set this setting below 1000, too many heartbeats can lead to performance degradation.
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
  * @param {Boolean} [options.useNewUrlParser=false] False by default. Set to `true` to opt in to the MongoDB driver's new URL parser logic.
- * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to opt in to the MongoDB driver's replica set and sharded cluster monitoring engine.
  * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
  * @param {Boolean} [options.useFindAndModify=true] True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
diff --git a/lib/index.js b/lib/index.js
index 4b1b72e4cdb..80a2b955c30 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -308,15 +308,17 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.
+ * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
+ * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to opt in to the MongoDB driver's replica set and sharded cluster monitoring engine.
+ * @param {Number} [options.serverSelectionTimeoutMS] If `useUnifiedTopology = true`, the MongoDB driver will try to find a server to send any given operation to, and keep retrying for `serverSelectionTimeoutMS` milliseconds before erroring out. If not set, the MongoDB driver defaults to using `30000` (30 seconds).
+ * @param {Number} [options.heartbeatFrequencyMS] If `useUnifiedTopology = true`, the MongoDB driver sends a heartbeat every `heartbeatFrequencyMS` to check on the status of the connection. A heartbeat is subject to `serverSelectionTimeoutMS`, so the MongoDB driver will retry failed heartbeats for up to 30 seconds by default. Mongoose only emits a `'disconnected'` event after a heartbeat has failed, so you may want to decrease this setting to reduce the time between when your server goes down and when Mongoose emits `'disconnected'`. We recommend you do **not** set this setting below 1000, too many heartbeats can lead to performance degradation.
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
  * @param {Boolean} [options.useNewUrlParser=false] False by default. Set to `true` to opt in to the MongoDB driver's new URL parser logic.
- * @param {Boolean} [options.useUnifiedTopology=false] False by default. Set to `true` to opt in to the MongoDB driver's replica set and sharded cluster monitoring engine.
  * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
  * @param {Boolean} [options.useFindAndModify=true] True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
  * @param {Class} [options.promiseLibrary] Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
- * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
  * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.

From ca8f5c94a38fd77c075d32f17db399b700ec3457 Mon Sep 17 00:00:00 2001
From: Elvis-Sarfo <54483575+Elvis-Sarfo@users.noreply.github.com>
Date: Fri, 5 Jun 2020 11:54:18 +0000
Subject: [PATCH 0944/2348] Revert "Corrected a typo in a code snippet."

This reverts commit b2e623ca0b8a5b2dfc6220f6d6eb1882e245bc4d.
---
 docs/api/mongoose.html | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/api/mongoose.html b/docs/api/mongoose.html
index 0574af4bcb3..f48284709bf 100644
--- a/docs/api/mongoose.html
+++ b/docs/api/mongoose.html
@@ -186,7 +186,7 @@ <h4>Example:</h4>
 <pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
 
 <span class="hljs-comment">// define an Actor model with this mongoose instance</span>
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
+<span class="hljs-keyword">const</span> Schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
 mongoose.model(<span class="hljs-string">'Actor'</span>, schema);
 
 <span class="hljs-comment">// create a new connection</span>
@@ -314,4 +314,4 @@ <h4>Example</h4>
       }
   };
 
-}(this, this.document));</script></div></body></html>
+}(this, this.document));</script></div></body></html>
\ No newline at end of file

From aedfbe4a127c9651464e0c3d66d3b5e8ba8baee7 Mon Sep 17 00:00:00 2001
From: Elvis-Sarfo <54483575+Elvis-Sarfo@users.noreply.github.com>
Date: Fri, 5 Jun 2020 12:09:15 +0000
Subject: [PATCH 0945/2348] Corrected a typo in the JSDoc

---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index 4b1b72e4cdb..dbf67afc516 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -416,7 +416,7 @@ Mongoose.prototype.pluralize = function(fn) {
  *     var mongoose = require('mongoose');
  *
  *     // define an Actor model with this mongoose instance
- *     const Schema = new Schema({ name: String });
+ *     const schema = new Schema({ name: String });
  *     mongoose.model('Actor', schema);
  *
  *     // create a new connection

From e83a7a86152dcc7b9110b47197ac669abce5d00a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 5 Jun 2020 17:43:52 +0200
Subject: [PATCH 0946/2348] test: repro #9096

---
 test/document.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 1d9dac4005e..8a10958f8c5 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9051,4 +9051,29 @@ describe('document', function() {
       assert.equal(doc.nested.prop, 'some default value');
     });
   });
+
+  describe('Document#getChanges(...) (gh-9096)', function() {
+    it('returns an empty object when there are no changes', function() {
+      return co(function*() {
+        const User = db.model('User', { name: String, age: Number, country: String });
+        const user = yield User.create({ name: 'Hafez', age: 25, country: 'Egypt' });
+
+        const changes = user.getChanges();
+        assert.deepEqual(changes, {});
+      });
+    });
+
+    it('returns only the changed paths', function() {
+      return co(function*() {
+        const User = db.model('User', { name: String, age: Number, country: String });
+        const user = yield User.create({ name: 'Hafez', age: 25, country: 'Egypt' });
+
+        user.country = undefined;
+        user.age = 26;
+
+        const changes = user.getChanges();
+        assert.deepEqual(changes, { $set: { age: 26 }, $unset: { country: 1 } });
+      });
+    });
+  });
 });

From 8be78a4eae051668cd6e5c3acca45c6dd1725ba4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 5 Jun 2020 17:49:25 +0200
Subject: [PATCH 0947/2348] feat(document): add Document#getChanges

---
 lib/document.js | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 72449083b3d..bc948ebea01 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3825,6 +3825,45 @@ Document.prototype.$__fullPath = function(path) {
   return path || '';
 };
 
+/**
+ * Returns the changes that happened to the document
+ * in the format that will be sent to MongoDB.
+ *
+ *  ###Example:
+ *   const userSchema = new Schema({
+ *     name: String,
+ *     age: Number,
+ *     country: String
+ *   });
+ *   const User = mongoose.model('User', userSchema);
+ *   const user = await User.create({
+ *     name: 'Hafez',
+ *     age: 25,
+ *     country: 'Egypt'
+ *   });
+ *
+ *   // returns an empty object, no changes happened yet
+ *   user.getChanges(); // { }
+ *
+ *   user.country = undefined;
+ *   user.age = 26;
+ *
+ *   user.getChanges(); // { $set: { age: 26 }, { $unset: { country: 1 } } }
+ *
+ *   await user.save();
+ *
+ *   user.getChanges(); // { }
+ *
+ * @return {Object} changes
+ */
+
+Document.prototype.getChanges = function() {
+  const delta = this.$__delta();
+
+  const changes = delta ? delta[1] : {};
+  return changes;
+};
+
 /*!
  * Module exports.
  */

From 611426137023b32f9d8c72e93776dd54c39f0488 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 5 Jun 2020 14:56:39 -0400
Subject: [PATCH 0948/2348] test(document): repro #9098

---
 test/document.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 1d9dac4005e..9c6bf268dee 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9051,4 +9051,22 @@ describe('document', function() {
       assert.equal(doc.nested.prop, 'some default value');
     });
   });
+
+  it('allows accessing $locals when initializing (gh-9098)', function() {
+    const personSchema = new mongoose.Schema({
+      name: {
+        first: String,
+        last: String
+      }
+    });
+
+    personSchema.virtual('fullName').
+      get(function() { return this.$locals.fullName; }).
+      set(function(newFullName) { this.$locals.fullName = newFullName; });
+
+    const Person = db.model('Person', personSchema);
+
+    const axl = new Person({ fullName: 'Axl Rose' });
+    assert.equal(axl.fullName, 'Axl Rose');
+  });
 });

From f9ddbc02f163b0d6b9d85b8f149ccd97e81ac222 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 5 Jun 2020 14:56:50 -0400
Subject: [PATCH 0949/2348] fix(document): allow accessing `$locals` when
 initializing document

Fix #9098
---
 lib/document.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 72449083b3d..e48c5a2b8b2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -85,6 +85,8 @@ function Document(obj, fields, skipId, options) {
   this.isNew = 'isNew' in options ? options.isNew : true;
   this.errors = undefined;
   this.$__.$options = options || {};
+  this.$locals = {};
+  this.$op = null;
 
   if (obj != null && typeof obj !== 'object') {
     throw new ObjectParameterError(obj, 'obj', 'Document');
@@ -158,8 +160,6 @@ function Document(obj, fields, skipId, options) {
   }
 
   this.$__._id = this._id;
-  this.$locals = {};
-  this.$op = null;
 
   if (!this.$__.strictMode && obj) {
     const _this = this;

From ab255452ba86bd38efa6391b2af6daec30f2092b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 5 Jun 2020 15:35:08 -0400
Subject: [PATCH 0950/2348] fix: improve atlas error in the event of incorrect
 password

Fix #9095
---
 lib/error/serverSelection.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index 45bf65b5c1f..c6d1bf64f95 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -26,7 +26,9 @@ class MongooseServerSelectionError extends MongooseError {
   assimilateError(err) {
     const reason = err.reason;
     // Special message for a case that is likely due to IP whitelisting issues.
-    const isAtlasWhitelistError = isAtlas(reason) && allServersUnknown(reason);
+    const isAtlasWhitelistError = isAtlas(reason) &&
+      allServersUnknown(reason) &&
+      err.message.indexOf('bad auth') === -1;
     this.message = isAtlasWhitelistError ?
       atlasMessage :
       err.message;

From 2d2e0a8ce69676690b97321e1d61f789f405055d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 5 Jun 2020 15:44:28 -0400
Subject: [PATCH 0951/2348] chore: release 5.9.18

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c26b25c6b0f..abc5cc12655 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.9.18 / 2020-06-05
+===================
+ * fix: improve atlas error in the event of incorrect password #9095
+ * docs: add edit link for all docs pages #9058
+ * fix(document): allow accessing `$locals` when initializing document #9099 #9098 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(query): make `setDefaultsOnInsert` a mongoose option so it doesn't end up in debug output #9086
+ * docs(connection+index): add serverSelectionTimeoutMS and heartbeatFrequencyMS to `connect()` and `openUri()` options #9071
+ * docs(geojson): add notes about geojson 2dsphere indexes #9044
+ * docs: make active page bold in navbar #9062
+ * docs: correct a typo in a code snippet #9089 [Elvis-Sarfo](https://github.com/Elvis-Sarfo)
+
 5.9.17 / 2020-06-02
 ===================
  * fix(document): avoid tracking changes like `splice()` on slice()-ed arrays #9011
diff --git a/package.json b/package.json
index a4a12abf53d..4d52679f515 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.17",
+  "version": "5.9.18",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 38908e034ae4414cfc3e421a11d5078c7fbfad95 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 6 Jun 2020 15:30:38 -0400
Subject: [PATCH 0952/2348] docs: add note about connections in `globalSetup`
 with Jest

Fix #9063
---
 docs/jest.pug | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/docs/jest.pug b/docs/jest.pug
index 2cb80547c36..16c5682b3c3 100644
--- a/docs/jest.pug
+++ b/docs/jest.pug
@@ -23,10 +23,11 @@ block content
     </div>
 
     Jest is a client-side JavaScript testing library developed by Facebook.
-    It was one of the libraries affected by [Facebook's licensing scandal in 2017](https://www.theregister.co.uk/2017/09/22/facebook_will_free_react_other_code_from_unloved_license/).
     Because Jest is designed primarily for testing React applications, using
     it to test Node.js server-side applications comes with a lot of caveats.
-    We strongly recommend using [Mocha](http://npmjs.com/package/mocha) instead.
+    We strongly advise against using Jest for testing any Node.js apps unless
+    you are an expert developer with an intimate knowledge of Jest.
+
     If you choose to delve into dangerous waters and test Mongoose apps with
     Jest, here's what you need to know:
 
@@ -87,6 +88,14 @@ block content
     sinon.stub(time, 'setTimeout');
     ```
 
+    ## `globalSetup` and `globalTeardown`
+
+    Do **not** use `globalSetup` to call `mongoose.connect()` or
+    `mongoose.createConnection()`. Jest runs `globalSetup` in
+    a [separate environment](https://github.com/facebook/jest/issues/7184),
+    so you cannot use any connections you create in `globalSetup`
+    in your tests.
+
     ## Further Reading
 
     Want to learn more about testing Mongoose apps? The

From 5df878f9215fde0ae58bc95f0e97a46fe6871e83 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 8 Jun 2020 20:12:11 -0400
Subject: [PATCH 0953/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 6c9b57e908c..c007987b812 100644
--- a/index.pug
+++ b/index.pug
@@ -370,6 +370,9 @@ html(lang='en')
               <a href="https://aussiecasinohex.com/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/aussiecasinohex/923df37/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.japanesecasino.com/">
+                <img class="sponsor" src="https://images.opencollective.com/japanesecasino/b0ffe3c/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 441bd69cb71ce15eb40d9b31aefbb70653436ea2 Mon Sep 17 00:00:00 2001
From: dfle <dianne@floqast.com>
Date: Tue, 9 Jun 2020 14:51:57 -0700
Subject: [PATCH 0954/2348] docs: add schema and how to set default sub-schema
 to schematype options

---
 docs/schematypes.pug | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 0e345936718..fc40f23da01 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -81,6 +81,7 @@ block content
     - [Array](#arrays)
     - [Decimal128](./api.html#mongoose_Mongoose-Decimal128)
     - [Map](#maps)
+    - [Schema](#schemas)
 
     <h4>Example</h4>
 
@@ -662,6 +663,28 @@ block content
     schema.path('arr.0.url').get(v => `${root}${v}`);
     ```
 
+    <h3 id="schemas"><a href="#schemas">Schemas</a></h3>
+
+    To declare a path as another [schema](./guide.html#definition),
+    set `type` to the sub-schema's instance.
+
+    To set a default value based on the sub-schema's shape, simply set a default value,
+    and the value will be cast based on the sub-schema's definition before being set
+    during document creation.
+
+    ```javascript
+    const subSchema = new mongoose.Schema({
+      // some schema definition here
+    });
+
+    const schema = new mongoose.Schema({
+      data: {
+        type: subSchema
+        default: {}
+      }
+    });
+    ```
+
     <h3 id="customtypes"><a href="#customtypes">Creating Custom Types</a></h3>
 
     Mongoose can also be extended with [custom SchemaTypes](customschematypes.html). Search the

From 1edcf06a39e3bf3494c065e23fe1880018f00624 Mon Sep 17 00:00:00 2001
From: ionware <ionwarez@gmail.com>
Date: Wed, 10 Jun 2020 20:22:38 +0100
Subject: [PATCH 0955/2348] docs: corrected markdown typo

---
 docs/models.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/models.pug b/docs/models.pug
index f3cd5e8540f..b47da9b52b5 100644
--- a/docs/models.pug
+++ b/docs/models.pug
@@ -52,7 +52,7 @@ block content
     ```
   :markdown
     The first argument is the _singular_ name of the collection your model is
-    for. ** Mongoose automatically looks for the plural, lowercased version of your model name. **
+    for. **Mongoose automatically looks for the plural, lowercased version of your model name.**
     Thus, for the example above, the model Tank is for the **tanks** collection
     in the database.
 

From ab0b3b294a87c09f28658016dd13627e2516dc48 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Jun 2020 17:23:27 -0400
Subject: [PATCH 0956/2348] chore: update opencollective sponsors

---
 index.pug | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/index.pug b/index.pug
index c007987b812..240258cb827 100644
--- a/index.pug
+++ b/index.pug
@@ -235,18 +235,12 @@ html(lang='en')
               <a href="https://proxybaylist.org/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy-bay/e176fe4/avatar.png" style="height: 100px">
               </a>
-              <a href="https://www.dcslsoftware.com/">
-                <img class="sponsor" src="https://images.opencollective.com/dcsl-software/a662911/logo.png" style="height: 100px">
-              </a>
               <a href="https://ghostinspector.com/">
                 <img class="sponsor" src="https://images.opencollective.com/ghostinspector/51b7be8/logo.png" style="height: 100px">
               </a>
               <a href="https://moneypug.co.uk/">
                 <img class="sponsor" src="https://images.opencollective.com/moneypug/45f8d53/logo.png" style="height: 100px">
               </a>
-              <a href="https://vpngorilla.com/">
-                <img class="sponsor" src="https://images.opencollective.com/vpngorilla-com/ae76cc5/logo.png" style="height: 100px">
-              </a>
               <a href="https://medium.com/@niksundin/best-web-design-companies-1872e445775f">
                 <img class="sponsor" src="https://images.opencollective.com/top-web-design-agencies/d92d747/logo.png" style="height: 100px">
               </a>
@@ -325,9 +319,6 @@ html(lang='en')
               <a href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
                 <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://alltimelist.com/">
-                <img class="sponsor" src="https://images.opencollective.com/all-time-list/b04f3ee/logo/256.png" style="height: 100px">
-              </a>
               <a href="https://casinomatcher.com/ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinomatcher-com/31fbd0d/logo/256.png" style="height: 100px">
               </a>

From 9d929a3c48b3945cd1f922e71623edf67c4f54fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 11 Jun 2020 13:29:26 -0400
Subject: [PATCH 0957/2348] docs(subdocs): add some notes on the difference
 between single nested subdocs and nested paths

Re: #9085
Fix #9046
---
 docs/guide.pug   |  6 +++--
 docs/subdocs.pug | 58 ++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 60 insertions(+), 4 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 389be5cb92f..f80b4770314 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -81,8 +81,10 @@ block content
     
     Keys may also be assigned nested objects containing further key/type definitions
     like the `meta` property above.  This will happen whenever a key's value is a POJO
-    that lacks a bona-fide `type` property.  In these cases, only the leaves in a tree
-    are given actual paths in the schema (like `meta.votes` and `meta.favs` above),
+    that doesn't have a `type` property.
+    
+    In these cases, Mongoose only creates actual schema paths for leaves
+    in the tree. (like `meta.votes` and `meta.favs` above),
     and the branches do not have actual paths.  A side-effect of this is that `meta`
     above cannot have its own validation.  If validation is needed up the tree, a path
     needs to be created up the tree - see the [Subdocuments](./subdocs.html) section
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index 78588429573..22ebaea9421 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -44,6 +44,7 @@ block content
   :markdown
     <ul class="toc">
       <li><a href="#what-is-a-subdocument-">What is a Subdocument?</a></li>
+      <li><a href="#subdocuments-versus-nested-paths">Subdocuments versus Nested Paths</a></li>
       <li><a href="#finding-a-subdocument">Finding a Subdocument</a></li>
       <li><a href="#adding-subdocs-to-arrays">Adding Subdocs to Arrays</a></li>
       <li><a href="#removing-subdocs">Removing Subdocs</a></li>
@@ -110,8 +111,8 @@ block content
     });
 
     var parentSchema = new mongoose.Schema({
-      child: childSchema,
-        });
+      child: childSchema
+    });
 
     parentSchema.pre('validate', function(next) {
       console.log('1');
@@ -124,6 +125,59 @@ block content
     });
     ```
 
+    ### Subdocuments versus Nested Paths
+
+    In Mongoose, nested paths are subtly different from subdocuments.
+    For example, below are two schemas: one with `child` as a subdocument,
+    and one with `child` as a nested path.
+
+    ```javascript
+    // Subdocument
+    const subdocumentSchema = new mongoose.Schema({
+      child: new mongoose.Schema({ name: String, age: Number })
+    });
+    const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
+
+    // Nested path
+    const nestedSchema = new mongoose.Schema({
+      child: { name: String, age: Number }
+    });
+    const Nested = mongoose.model('Nested', nestedSchema);
+    ```
+
+    These two schemas look similar, and the documents in MongoDB will
+    have the same structure with both schemas. But there are a few
+    Mongoose-specific differences:
+
+    First, instances of `Nested` never have `child === undefined`.
+    You can always set subproperties of `child`, even if you don't set
+    the `child` property. But instances of `Subdoc` can have `child === undefined`.
+
+    ```javascript
+    const doc1 = new Subdoc({});
+    doc1.child === undefined; // true
+    doc1.child.name = 'test'; // Throws TypeError: cannot read property...
+
+    const doc2 = new Nested({});
+    doc2.child === undefined; // false
+    console.log(doc2.child); // Prints 'MongooseDocument { undefined }'
+    doc2.child.name = 'test'; // Works
+    ```
+
+    Secondly, in Mongoose 5, [`Document#set()`](/docs/api/document.html#document_Document-set)
+    merges when you call it on a nested path, but overwrites when you call
+    it on a subdocument.
+
+    ```javascript
+    const doc1 = new Subdoc({ child: { name: 'Luke', age: 19 } });
+    doc1.set({ child: { age: 21 } });
+    doc1.child; // { age: 21 }
+
+    const doc2 = new Nested({ child: { name: 'Luke', age: 19 } });
+    doc2.set({ child: { age: 21 } });
+    doc2.child; // { name: Luke, age: 21 }
+    ```
+
   h3#finding-a-subdocument Finding a Subdocument
   :markdown
     Each subdocument has an `_id` by default. Mongoose document arrays have a

From 908d46b33a66aa9982af625d3f9be0b34ff2b794 Mon Sep 17 00:00:00 2001
From: Thomas <t.champagne@sesamm.com>
Date: Fri, 12 Jun 2020 10:30:56 +0200
Subject: [PATCH 0958/2348] fix(castArrayFilters): handle casting on all fields
 of array filter

---
 lib/helpers/update/castArrayFilters.js       | 57 ++++++++++----------
 test/helpers/update.castArrayFilters.test.js | 25 +++++++++
 2 files changed, 54 insertions(+), 28 deletions(-)

diff --git a/lib/helpers/update/castArrayFilters.js b/lib/helpers/update/castArrayFilters.js
index 471fda35a38..57018d9fb10 100644
--- a/lib/helpers/update/castArrayFilters.js
+++ b/lib/helpers/update/castArrayFilters.js
@@ -38,40 +38,41 @@ module.exports = function castArrayFilters(query) {
     if (filter == null) {
       throw new Error(`Got null array filter in ${arrayFilters}`);
     }
-    const firstKey = Object.keys(filter)[0];
+    for (const key in filter) {
 
-    if (filter[firstKey] == null) {
-      continue;
-    }
+      if (filter[key] == null) {
+        continue;
+      }
 
-    const dot = firstKey.indexOf('.');
-    let filterPath = dot === -1 ?
-      updatedPathsByFilter[firstKey] + '.0' :
-      updatedPathsByFilter[firstKey.substr(0, dot)] + '.0' + firstKey.substr(dot);
+      const dot = key.indexOf('.');
+      let filterPath = dot === -1 ?
+        updatedPathsByFilter[key] + '.0' :
+        updatedPathsByFilter[key.substr(0, dot)] + '.0' + key.substr(dot);
 
-    if (filterPath == null) {
-      throw new Error(`Filter path not found for ${firstKey}`);
-    }
+      if (filterPath == null) {
+        throw new Error(`Filter path not found for ${key}`);
+      }
 
-    // If there are multiple array filters in the path being updated, make sure
-    // to replace them so we can get the schema path.
-    filterPath = cleanPositionalOperators(filterPath);
+      // If there are multiple array filters in the path being updated, make sure
+      // to replace them so we can get the schema path.
+      filterPath = cleanPositionalOperators(filterPath);
 
-    const schematype = getPath(schema, filterPath);
-    if (schematype == null) {
-      if (!strictQuery) {
-        return;
+      const schematype = getPath(schema, filterPath);
+      if (schematype == null) {
+        if (!strictQuery) {
+          return;
+        }
+        // For now, treat `strictQuery = true` and `strictQuery = 'throw'` as
+        // equivalent for casting array filters. `strictQuery = true` doesn't
+        // quite work in this context because we never want to silently strip out
+        // array filters, even if the path isn't in the schema.
+        throw new Error(`Could not find path "${filterPath}" in schema`);
+      }
+      if (typeof filter[key] === 'object') {
+        filter[key] = castFilterPath(query, schematype, filter[key]);
+      } else {
+        filter[key] = schematype.castForQuery(filter[key]);
       }
-      // For now, treat `strictQuery = true` and `strictQuery = 'throw'` as
-      // equivalent for casting array filters. `strictQuery = true` doesn't
-      // quite work in this context because we never want to silently strip out
-      // array filters, even if the path isn't in the schema.
-      throw new Error(`Could not find path "${filterPath}" in schema`);
-    }
-    if (typeof filter[firstKey] === 'object') {
-      filter[firstKey] = castFilterPath(query, schematype, filter[firstKey]);
-    } else {
-      filter[firstKey] = schematype.castForQuery(filter[firstKey]);
     }
   }
 };
\ No newline at end of file
diff --git a/test/helpers/update.castArrayFilters.test.js b/test/helpers/update.castArrayFilters.test.js
index 17e64de2991..e78e9d8dffc 100644
--- a/test/helpers/update.castArrayFilters.test.js
+++ b/test/helpers/update.castArrayFilters.test.js
@@ -42,6 +42,31 @@ describe('castArrayFilters', function() {
     done();
   });
 
+  it('casts on multiple fields', function (done) {
+    const schema = new Schema({
+      comments: [{
+        text: String,
+        replies: [{ 
+          beginAt: Date, 
+          endAt: Date
+        }]
+      }]
+    });
+    const q = new Query();
+    q.schema = schema;
+
+    q.updateOne({}, { $set: { 'comments.$[x].replies.$[y].endAt': '2019-01-01' } }, {
+      arrayFilters: [{ 'x.text': 123 }, { 'y.beginAt': { $gte: '2018-01-01' }, 'y.endAt': { $lt: '2020-01-01' } }]
+    });
+    castArrayFilters(q);
+
+    assert.strictEqual(q.options.arrayFilters[0]['x.text'], '123');
+    assert.ok(q.options.arrayFilters[1]['y.beginAt'].$gte instanceof Date);
+    assert.ok(q.options.arrayFilters[1]['y.endAt'].$lt instanceof Date);
+
+    done();
+  });
+
   it('sane error on same filter twice', function(done) {
     const schema = new Schema({
       comments: [{

From afc50c3fd3d550814a9271a8b9e9dd00b58585cf Mon Sep 17 00:00:00 2001
From: Thomas <t.champagne@sesamm.com>
Date: Fri, 12 Jun 2020 10:58:22 +0200
Subject: [PATCH 0959/2348] fix linter on cast array filters test

---
 test/helpers/update.castArrayFilters.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/helpers/update.castArrayFilters.test.js b/test/helpers/update.castArrayFilters.test.js
index e78e9d8dffc..fac39ca9fc1 100644
--- a/test/helpers/update.castArrayFilters.test.js
+++ b/test/helpers/update.castArrayFilters.test.js
@@ -42,12 +42,12 @@ describe('castArrayFilters', function() {
     done();
   });
 
-  it('casts on multiple fields', function (done) {
+  it('casts on multiple fields', function(done) {
     const schema = new Schema({
       comments: [{
         text: String,
-        replies: [{ 
-          beginAt: Date, 
+        replies: [{
+          beginAt: Date,
           endAt: Date
         }]
       }]

From 483a1b45b7de105b8b366d3fd77e7c33f39f97d1 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 12 Jun 2020 16:33:06 +0200
Subject: [PATCH 0960/2348] Upgrade mongodb driver to 3.5.9

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 4d52679f515..a719c94ab89 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.5.8",
+    "mongodb": "3.5.9",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From de468c1288325b98b1465c0084d7213ab79c83ef Mon Sep 17 00:00:00 2001
From: dmcgrouther <dbmcgrouther@gmail.com>
Date: Fri, 12 Jun 2020 11:13:36 -0700
Subject: [PATCH 0961/2348] Updated index.pug to ES6

Where this file has "var" I am proposing it be changed to "const".
---
 docs/index.pug | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/docs/index.pug b/docs/index.pug
index 656c4db626f..c2b161fe421 100644
--- a/docs/index.pug
+++ b/docs/index.pug
@@ -31,7 +31,7 @@ block content
 
     ```javascript
     // getting-started.js
-    var mongoose = require('mongoose');
+    const mongoose = require('mongoose');
     mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true});
     ```
 
@@ -40,7 +40,7 @@ block content
     error occurs:
 
     ```javascript
-    var db = mongoose.connection;
+    const db = mongoose.connection;
     db.on('error', console.error.bind(console, 'connection error:'));
     db.once('open', function() {
       // we're connected!
@@ -54,7 +54,7 @@ block content
     Let's get a reference to it and define our kittens.
 
     ```javascript
-    var kittySchema = new mongoose.Schema({
+    const kittySchema = new mongoose.Schema({
       name: String
     });
     ```
@@ -62,7 +62,7 @@ block content
     So far so good. We've got a schema with one property, `name`, which will be a  `String`. The next step is compiling our schema into a [Model](/docs/models.html).
 
     ```javascript
-    var Kitten = mongoose.model('Kitten', kittySchema);
+    const Kitten = mongoose.model('Kitten', kittySchema);
     ```
 
     A model is a class with which we construct documents.
@@ -70,7 +70,7 @@ block content
     Let's create a kitten document representing the little guy we just met on the sidewalk outside:
 
     ```javascript
-    var silence = new Kitten({ name: 'Silence' });
+    const silence = new Kitten({ name: 'Silence' });
     console.log(silence.name); // 'Silence'
     ```
 
@@ -80,20 +80,20 @@ block content
     ```javascript
     // NOTE: methods must be added to the schema before compiling it with mongoose.model()
     kittySchema.methods.speak = function () {
-      var greeting = this.name
+      const greeting = this.name
         ? "Meow name is " + this.name
         : "I don't have a name";
       console.log(greeting);
     }
 
-    var Kitten = mongoose.model('Kitten', kittySchema);
+    const Kitten = mongoose.model('Kitten', kittySchema);
     ```
 
     Functions added to the `methods` property of a schema get compiled into
     the `Model` prototype and exposed on each document instance:
 
     ```javascript
-    var fluffy = new Kitten({ name: 'fluffy' });
+    const fluffy = new Kitten({ name: 'fluffy' });
     fluffy.speak(); // "Meow name is fluffy"
     ```
 

From ae71975ce7a9b367a17d3843c21c8abf9e86664c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 14:58:24 -0400
Subject: [PATCH 0962/2348] test(update): repro #9105

---
 test/model.update.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 1b6b677cfea..dce6720067d 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3382,6 +3382,27 @@ describe('model: updateOne: ', function() {
       then(doc => assert.strictEqual(doc.nested.notInSchema, void 0));
   });
 
+  it('handles timestamp properties in nested paths when overwriting parent path (gh-9105)', function() {
+    const SampleSchema = Schema({ nested: { test: String } }, {
+      timestamps: {
+        updatedAt: 'nested.updatedAt'
+      }
+    });
+    const Test = db.model('Test', SampleSchema);
+
+    return co(function*() {
+      const doc = yield Test.create({ nested: { test: 'foo' } });
+      assert.ok(doc.nested.updatedAt);
+
+      yield cb => setTimeout(cb, 10);
+      yield Test.updateOne({ _id: doc._id }, { nested: { test: 'bar' } });
+
+      const fromDb = yield Test.findOne({ _id: doc._id });
+      assert.ok(fromDb.nested.updatedAt);
+      assert.ok(fromDb.nested.updatedAt > doc.nested.updatedAt);
+    });
+  });
+
   describe('mongodb 42 features', function() {
     before(function(done) {
       start.mongodVersion((err, version) => {

From 2803c51a8c8d9a66d0e2b1a3ed785fec7d32de3c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 14:58:37 -0400
Subject: [PATCH 0963/2348] fix(update): handle nested path updatedAt when
 overwriting parent path

Re: #9105
---
 lib/helpers/update/applyTimestampsToUpdate.js | 23 ++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/update/applyTimestampsToUpdate.js b/lib/helpers/update/applyTimestampsToUpdate.js
index 7318232b38b..074d586122f 100644
--- a/lib/helpers/update/applyTimestampsToUpdate.js
+++ b/lib/helpers/update/applyTimestampsToUpdate.js
@@ -52,7 +52,28 @@ function applyTimestampsToUpdate(now, createdAt, updatedAt, currentUpdate, optio
   updates.$set = updates.$set || {};
   if (!skipUpdatedAt && updatedAt &&
       (!currentUpdate.$currentDate || !currentUpdate.$currentDate[updatedAt])) {
-    updates.$set[updatedAt] = now;
+    let timestampSet = false;
+    if (updatedAt.indexOf('.') !== -1) {
+      const pieces = updatedAt.split('.');
+      for (let i = 1; i < pieces.length; ++i) {
+        const remnant = pieces.slice(-i).join('.');
+        const start = pieces.slice(0, -i).join('.');
+        if (currentUpdate[start] != null) {
+          currentUpdate[start][remnant] = now;
+          timestampSet = true;
+          break;
+        } else if (currentUpdate.$set && currentUpdate.$set[start]) {
+          currentUpdate.$set[start][remnant] = now;
+          timestampSet = true;
+          break;
+        }
+      }
+    }
+
+    if (!timestampSet) {
+      updates.$set[updatedAt] = now;
+    }
+
     if (updates.hasOwnProperty(updatedAt)) {
       delete updates[updatedAt];
     }

From ec98026303821cc52e1793b67a2552039bfa6be4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 15:52:41 -0400
Subject: [PATCH 0964/2348] fix(update): handle nested path createdAt when
 overwriting parent path

Fix #9105
---
 lib/helpers/update/applyTimestampsToUpdate.js | 24 +++++++++++++++++--
 test/model.update.test.js                     |  4 ++++
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/update/applyTimestampsToUpdate.js b/lib/helpers/update/applyTimestampsToUpdate.js
index 074d586122f..27d6e32ca3b 100644
--- a/lib/helpers/update/applyTimestampsToUpdate.js
+++ b/lib/helpers/update/applyTimestampsToUpdate.js
@@ -87,8 +87,28 @@ function applyTimestampsToUpdate(now, createdAt, updatedAt, currentUpdate, optio
       delete currentUpdate.$set[createdAt];
     }
 
-    updates.$setOnInsert = updates.$setOnInsert || {};
-    updates.$setOnInsert[createdAt] = now;
+    let timestampSet = false;
+    if (createdAt.indexOf('.') !== -1) {
+      const pieces = createdAt.split('.');
+      for (let i = 1; i < pieces.length; ++i) {
+        const remnant = pieces.slice(-i).join('.');
+        const start = pieces.slice(0, -i).join('.');
+        if (currentUpdate[start] != null) {
+          currentUpdate[start][remnant] = now;
+          timestampSet = true;
+          break;
+        } else if (currentUpdate.$set && currentUpdate.$set[start]) {
+          currentUpdate.$set[start][remnant] = now;
+          timestampSet = true;
+          break;
+        }
+      }
+    }
+
+    if (!timestampSet) {
+      updates.$setOnInsert = updates.$setOnInsert || {};
+      updates.$setOnInsert[createdAt] = now;
+    }
   }
 
   if (Object.keys(updates.$set).length === 0) {
diff --git a/test/model.update.test.js b/test/model.update.test.js
index dce6720067d..8e8c517d865 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3385,6 +3385,7 @@ describe('model: updateOne: ', function() {
   it('handles timestamp properties in nested paths when overwriting parent path (gh-9105)', function() {
     const SampleSchema = Schema({ nested: { test: String } }, {
       timestamps: {
+        createdAt: 'nested.createdAt',
         updatedAt: 'nested.updatedAt'
       }
     });
@@ -3393,6 +3394,7 @@ describe('model: updateOne: ', function() {
     return co(function*() {
       const doc = yield Test.create({ nested: { test: 'foo' } });
       assert.ok(doc.nested.updatedAt);
+      assert.ok(doc.nested.createdAt);
 
       yield cb => setTimeout(cb, 10);
       yield Test.updateOne({ _id: doc._id }, { nested: { test: 'bar' } });
@@ -3400,6 +3402,8 @@ describe('model: updateOne: ', function() {
       const fromDb = yield Test.findOne({ _id: doc._id });
       assert.ok(fromDb.nested.updatedAt);
       assert.ok(fromDb.nested.updatedAt > doc.nested.updatedAt);
+      assert.ok(fromDb.nested.createdAt);
+      assert.ok(fromDb.nested.createdAt > doc.nested.createdAt);
     });
   });
 

From c8b84bdc64f7d073d3376c11628694c8a2ed3470 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 17:20:26 -0400
Subject: [PATCH 0965/2348] test(discriminator): repro #9108

---
 test/model.discriminator.test.js | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index d805a35b301..658ee77cba5 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1074,7 +1074,7 @@ describe('model', function() {
         catch(done);
     });
 
-    it('embedded with single nested subdocs and tied value (gh-8164)', function() {
+    it('embedded with single nested subdocs and tied value (gh-8164) (gh-9108)', function() {
       const eventSchema = new Schema({ message: String },
         { discriminatorKey: 'kind', _id: false });
 
@@ -1087,13 +1087,13 @@ describe('model', function() {
       }, { _id: false }), 'purchase');
 
       const MyModel = db.model('Test1', trackSchema);
-      const doc1 = {
+      let doc1 = {
         event: {
           kind: 'click',
           element: 'Amazon Link'
         }
       };
-      const doc2 = {
+      let doc2 = {
         event: {
           kind: 'purchase',
           product: 'Professional AngularJS'
@@ -1101,8 +1101,8 @@ describe('model', function() {
       };
       return MyModel.create([doc1, doc2]).
         then(function(docs) {
-          const doc1 = docs[0];
-          const doc2 = docs[1];
+          doc1 = docs[0];
+          doc2 = docs[1];
 
           assert.equal(doc1.event.kind, 'click');
           assert.equal(doc1.event.element, 'Amazon Link');
@@ -1111,6 +1111,14 @@ describe('model', function() {
           assert.equal(doc2.event.kind, 'purchase');
           assert.equal(doc2.event.product, 'Professional AngularJS');
           assert.ok(!doc2.event.element);
+
+          return MyModel.updateOne({ 'event.kind': 'click' }, {
+            'event.element': 'Pluralsight Link'
+          });
+        }).
+        then(() => MyModel.findById(doc1._id)).
+        then(doc => {
+          assert.equal(doc.event.element, 'Pluralsight Link');
         });
     });
 

From 40308d4090621df09b7839f8bef43c8a19d84fd7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 17:20:36 -0400
Subject: [PATCH 0966/2348] fix(discriminator): handle `tiedValue` when casting
 update on nested paths

Fix #9108
---
 lib/helpers/query/getEmbeddedDiscriminatorPath.js | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/query/getEmbeddedDiscriminatorPath.js b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
index ff297ace6ff..395ea75c4bf 100644
--- a/lib/helpers/query/getEmbeddedDiscriminatorPath.js
+++ b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
@@ -2,6 +2,7 @@
 
 const cleanPositionalOperators = require('../schema/cleanPositionalOperators');
 const get = require('../get');
+const getDiscriminatorByValue = require('../discriminator/getDiscriminatorByValue');
 
 /*!
  * Like `schema.path()`, except with a document, because impossible to
@@ -26,7 +27,6 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
     type = schema.pathType(subpath);
     if ((schematype.$isSingleNested || schematype.$isMongooseDocumentArrayElement) &&
         schematype.schema.discriminators != null) {
-      const discriminators = schematype.schema.discriminators;
       const key = get(schematype, 'schema.options.discriminatorKey');
       const discriminatorValuePath = subpath + '.' + key;
       const discriminatorFilterPath =
@@ -49,13 +49,16 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
         discriminatorKey = update[discriminatorValuePath];
       }
 
-      if (discriminatorKey == null || discriminators[discriminatorKey] == null) {
+      if (discriminatorKey == null) {
         continue;
       }
+
+      const discriminatorSchema = getDiscriminatorByValue(schematype.caster, discriminatorKey).schema;
+
       const rest = parts.slice(i + 1).join('.');
-      schematype = discriminators[discriminatorKey].path(rest);
+      schematype = discriminatorSchema.path(rest);
       if (schematype != null) {
-        type = discriminators[discriminatorKey]._getPathType(rest);
+        type = discriminatorSchema._getPathType(rest);
         break;
       }
     }

From 22b020396874119755d6030f3a0fad9ba98569cf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 17:39:51 -0400
Subject: [PATCH 0967/2348] chore: remove some done() calls that ended up
 leaking in from merge conflicts

---
 test/model.discriminator.test.js | 44 ++++++++++++++++----------------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index d84b65c4361..f0abb5c1630 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -87,12 +87,12 @@ describe('model', function() {
       Employee = Person.discriminator('Employee', EmployeeSchema);
     });
 
-    it('model defaults without discriminator', function(done) {
+    it('model defaults without discriminator', function() {
       const Model = db.model('Test1', new Schema());
       assert.equal(Model.discriminators, undefined);
     });
 
-    it('is instance of root', function(done) {
+    it('is instance of root', function() {
       assert.equal(Employee.baseModelName, 'Test');
       const employee = new Employee();
       assert.ok(employee instanceof Person);
@@ -101,7 +101,7 @@ describe('model', function() {
       assert.strictEqual(employee.__proto__.__proto__.constructor, Person);
     });
 
-    it('can define static and instance methods', function(done) {
+    it('can define static and instance methods', function() {
       function BossBaseSchema() {
         Schema.apply(this, arguments);
 
@@ -141,13 +141,13 @@ describe('model', function() {
       done();
     });
 
-    it('adds discriminatorKey to schema with default as name', function(done) {
+    it('adds discriminatorKey to schema with default as name', function() {
       const type = Employee.schema.paths.__t;
       assert.equal(type.options.type, String);
       assert.equal(type.options.default, 'Employee');
     });
 
-    it('adds discriminator to Model.discriminators object', function(done) {
+    it('adds discriminator to Model.discriminators object', function() {
       assert.equal(Object.keys(Person.discriminators).length, 1);
       assert.equal(Person.discriminators['Employee'], Employee);
       const newName = 'model-discriminator-' + random();
@@ -156,7 +156,7 @@ describe('model', function() {
       assert.equal(Person.discriminators[newName], NewDiscriminatorType);
     });
 
-    it('throws error on invalid schema', function(done) {
+    it('throws error on invalid schema', function() {
       assert.throws(
         function() {
           Person.discriminator('Foo');
@@ -165,7 +165,7 @@ describe('model', function() {
       );
     });
 
-    it('throws error when attempting to nest discriminators', function(done) {
+    it('throws error when attempting to nest discriminators', function() {
       assert.throws(
         function() {
           Employee.discriminator('model-discriminator-foo', new Schema());
@@ -174,7 +174,7 @@ describe('model', function() {
       );
     });
 
-    it('throws error when discriminator has mapped discriminator key in schema', function(done) {
+    it('throws error when discriminator has mapped discriminator key in schema', function() {
       assert.throws(
         function() {
           Person.discriminator('model-discriminator-foo', new Schema({ __t: String }));
@@ -193,7 +193,7 @@ describe('model', function() {
       );
     });
 
-    it('throws error when discriminator with taken name is added', function(done) {
+    it('throws error when discriminator with taken name is added', function() {
       const Foo = db.model('Test1', new Schema({}));
       Foo.discriminator('Token', new Schema());
       assert.throws(
@@ -204,7 +204,7 @@ describe('model', function() {
       );
     });
 
-    it('throws error if model name is taken (gh-4148)', function(done) {
+    it('throws error if model name is taken (gh-4148)', function() {
       const Foo = db.model('Test1', new Schema({}));
       db.model('Test', new Schema({}));
       assert.throws(
@@ -259,7 +259,7 @@ describe('model', function() {
         done();
       });
 
-      it('is not customizable', function(done) {
+      it('is not customizable', function() {
         const CustomizedSchema = new Schema({}, { capped: true });
 
         assert.throws(function() {
@@ -269,18 +269,18 @@ describe('model', function() {
     });
 
     describe('root schema inheritance', function() {
-      it('inherits field mappings', function(done) {
+      it('inherits field mappings', function() {
         assert.strictEqual(Employee.schema.path('name'), Person.schema.path('name'));
         assert.strictEqual(Employee.schema.path('gender'), Person.schema.path('gender'));
         assert.equal(Person.schema.paths.department, undefined);
       });
 
-      it('inherits validators', function(done) {
+      it('inherits validators', function() {
         assert.strictEqual(Employee.schema.path('gender').validators, PersonSchema.path('gender').validators);
         assert.strictEqual(Employee.schema.path('department').validators, EmployeeSchema.path('department').validators);
       });
 
-      it('does not inherit and override fields that exist', function(done) {
+      it('does not inherit and override fields that exist', function() {
         const FemaleSchema = new Schema({ gender: { type: String, default: 'F' } }),
             Female = Person.discriminator('model-discriminator-female', FemaleSchema);
 
@@ -291,20 +291,20 @@ describe('model', function() {
         assert.equal(gender.options.default, 'F');
       });
 
-      it('inherits methods', function(done) {
+      it('inherits methods', function() {
         const employee = new Employee();
         assert.strictEqual(employee.getFullName, PersonSchema.methods.getFullName);
         assert.strictEqual(employee.getDepartment, EmployeeSchema.methods.getDepartment);
         assert.equal((new Person).getDepartment, undefined);
       });
 
-      it('inherits statics', function(done) {
+      it('inherits statics', function() {
         assert.strictEqual(Employee.findByGender, PersonSchema.statics.findByGender);
         assert.strictEqual(Employee.findByDepartment, EmployeeSchema.statics.findByDepartment);
         assert.equal(Person.findByDepartment, undefined);
       });
 
-      it('inherits virtual (g.s)etters', function(done) {
+      it('inherits virtual (g.s)etters', function() {
         const employee = new Employee();
         employee.name.full = 'John Doe';
         assert.equal(employee.name.full, 'John Doe');
@@ -315,7 +315,7 @@ describe('model', function() {
         assert.deepEqual(Employee.schema.indexes(), [[{ department: 1 }, { background: true }]]);
       });
 
-      it('gets options overridden by root options except toJSON and toObject', function(done) {
+      it('gets options overridden by root options except toJSON and toObject', function() {
         const personOptions = clone(Person.schema.options),
             employeeOptions = clone(Employee.schema.options);
 
@@ -369,7 +369,7 @@ describe('model', function() {
           });
       });
 
-      it('with typeKey (gh-4339)', function(done) {
+      it('with typeKey (gh-4339)', function() {
         const options = { typeKey: '$type', discriminatorKey: '_t' };
         const schema = new Schema({ test: { $type: String } }, options);
         const Model = db.model('Test', schema);
@@ -671,7 +671,7 @@ describe('model', function() {
           });
       });
 
-      it('reusing schema for discriminators (gh-5684)', function(done) {
+      it('reusing schema for discriminators (gh-5684)', function() {
         const ParentSchema = new Schema({});
         const ChildSchema = new Schema({ name: String });
 
@@ -699,7 +699,7 @@ describe('model', function() {
         assert.equal(doc2.things[0].name, 'test');
       });
 
-      it('overwrites nested paths in parent schema (gh-6076)', function(done) {
+      it('overwrites nested paths in parent schema (gh-6076)', function() {
         const schema = mongoose.Schema({
           account: {
             type: Object
@@ -1576,4 +1576,4 @@ describe('model', function() {
     const doc = new D({ run: { tab: { id: 42 } } });
     assert.ifError(doc.validateSync());
   });
-});
\ No newline at end of file
+});

From 94137db7ac223a5c565b61b3d306d857490377fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Jun 2020 17:43:24 -0400
Subject: [PATCH 0968/2348] chore: one more missing `done()`

---
 test/model.discriminator.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index f0abb5c1630..d6fe821c625 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -183,7 +183,7 @@ describe('model', function() {
       );
     });
 
-    it('throws error when discriminator has mapped discriminator key in schema with discriminatorKey option set', function(done) {
+    it('throws error when discriminator has mapped discriminator key in schema with discriminatorKey option set', function() {
       assert.throws(
         function() {
           const Foo = db.model('Test1', new Schema({}, { discriminatorKey: '_type' }));

From f80e7b0415a0dd27409e392168538e9453a5809f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 11:03:09 -0400
Subject: [PATCH 0969/2348] docs(subdocs): improve docs on `typePojoToMixed`

Fix #9085
---
 docs/subdocs.pug | 64 ++++++++++++++++++++++++++++++++++++------------
 1 file changed, 49 insertions(+), 15 deletions(-)

diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index 22ebaea9421..50b4c31b051 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -276,8 +276,9 @@ block content
 
   h4#altsyntaxarrays Alternate declaration syntax for arrays
   :markdown
-    If you create a schema with an array of objects, mongoose will automatically
+    If you create a schema with an array of objects, Mongoose will automatically
     convert the object to a schema for you:
+
     ```javascript
     var parentSchema = new Schema({
       children: [{ name: 'string' }]
@@ -288,25 +289,58 @@ block content
     });
     ```
 
-  h4#altsyntaxsingle Alternate declaration syntax for single subdocuments
+  h4#altsyntaxsingle Alternate declaration syntax for single nested subdocuments
   :markdown
-    Similarly, single subdocuments also have a shorthand whereby you can omit
-    wrapping the schema with an instance of Schema.  However, for historical
-    reasons, this alternate declaration must be enabled via an option (either
-    on the parent schema instantiation or on the mongoose instance).
+    Unlike document arrays, Mongoose 5 does not convert an objects in schemas
+    into nested schemas. In the below example, `nested` is a _nested path_
+    rather than a subdocument.
+
     ```javascript
-    var parentSchema = new Schema({
-      child: { type: { name: 'string' } }
-    }, { typePojoToMixed: false });
-    // Equivalent
-    var parentSchema = new Schema({
-      child: new Schema({ name: 'string' })
+    const schema = new Schema({
+      nested: {
+        prop: String
+      }
     });
-    // Not equivalent!  Careful - a Mixed path is created instead!
-    var parentSchema = new Schema({
-      child: { type: { name: 'string' } }
+    ```
+
+    This leads to some surprising behavior when you attempt to define a
+    nested path with validators or getters/setters.
+
+    ```javascript
+    const schema = new Schema({
+      nested: {
+        // Do not do this! This makes `nested` a mixed path in Mongoose 5
+        type: { prop: String },
+        required: true
+      }
+    });
+
+    const schema = new Schema({
+      nested: {
+        // This works correctly
+        type: new Schema({ prop: String }),
+        required: true
+      }
     });
     ```
+
+    Surprisingly, declaring `nested` with an object `type` makes `nested`
+    into a path of type [Mixed](/docs/schematypes.html#mixed). To instead
+    make Mongoose automatically convert `type: { prop: String }` into
+    `type: new Schema({ prop: String })`, set the `typePojoToMixed` option
+    to `false`.
+
+    ```javascript
+    const schema = new Schema({
+      nested: {
+        // Because of `typePojoToMixed`, Mongoose knows to
+        // wrap `{ prop: String }` in a `new Schema()`.
+        type: { prop: String },
+        required: true
+      }
+    }, { typePojoToMixed: false });
+    ```
+
   h3#next Next Up
   :markdown
     Now that we've covered Subdocuments, let's take a look at

From 21cdc0583d0f7bc276c61767ab03b9d99101fb59 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 15:20:25 -0400
Subject: [PATCH 0970/2348] test(schema): repro #9091

---
 test/model.indexes.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 41ff749f85e..f290ab2de51 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -452,6 +452,23 @@ describe('model', function() {
     });
   });
 
+  it('sets correct partialFilterExpression for document array (gh-9091)', function() {
+    const childSchema = new Schema({ name: String });
+    childSchema.index({ name: 1 }, { partialFilterExpression: { name: { $exists: true } } });
+    const schema = new Schema({ arr: [childSchema] });
+    const Model = db.model('Test', schema);
+
+    return Model.init().
+      then(() => Model.listIndexes()).
+      then(indexes => {
+        assert.equal(indexes.length, 2);
+        assert.ok(indexes[1].partialFilterExpression);
+        assert.deepEqual(indexes[1].partialFilterExpression, {
+          'arr.name': { $exists: true }
+        });
+      });
+  });
+
   describe('discriminators with unique', function() {
     this.timeout(5000);
 

From e2e07550e3c0520df7aba0cc9262302a85be8438 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 15:20:26 -0400
Subject: [PATCH 0971/2348] fix(schema): correctly set partialFilterExpression
 for nested schema indexes

Fix #9091
---
 lib/helpers/schema/getIndexes.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index ce4286be45a..52a275ee607 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -125,6 +125,7 @@ module.exports = function getIndexes(schema) {
     const len = subindexes.length;
     for (let i = 0; i < len; ++i) {
       const indexObj = subindexes[i][0];
+      const indexOptions = subindexes[i][1];
       const keys = Object.keys(indexObj);
       const klen = keys.length;
       const newindex = {};
@@ -135,7 +136,17 @@ module.exports = function getIndexes(schema) {
         newindex[prefix + key] = indexObj[key];
       }
 
-      indexes.push([newindex, subindexes[i][1]]);
+      const newIndexOptions = Object.assign({}, indexOptions);
+      if (indexOptions != null && indexOptions.partialFilterExpression != null) {
+        newIndexOptions.partialFilterExpression = {};
+        const partialFilterExpression = indexOptions.partialFilterExpression;
+        for (const key of Object.keys(partialFilterExpression)) {
+          newIndexOptions.partialFilterExpression[prefix + key] =
+            partialFilterExpression[key];
+        }
+      }
+
+      indexes.push([newindex, newIndexOptions]);
     }
   }
 };

From 473bc36ec99a3261e631162da9ab9c17bb8eb281 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 15:24:38 -0400
Subject: [PATCH 0972/2348] test: fix tests

---
 test/model.indexes.test.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index f290ab2de51..89b3db7d981 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -459,6 +459,7 @@ describe('model', function() {
     const Model = db.model('Test', schema);
 
     return Model.init().
+      then(() => Model.syncIndexes()).
       then(() => Model.listIndexes()).
       then(indexes => {
         assert.equal(indexes.length, 2);

From 2f8152172761dfa0464bfda82c6774148763f1f5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 17:09:16 -0400
Subject: [PATCH 0973/2348] feat(SingleNestedPath+DocumentArray): add static
 `set()` function for global options, support setting `_id` globally

Fix #8883
---
 lib/schema.js                        |  6 ++++++
 lib/schema/SingleNestedPath.js       | 18 ++++++++++++++++++
 lib/schema/documentarray.js          | 18 ++++++++++++++++++
 test/schema.documentarray.test.js    | 16 ++++++++++++++++
 test/schema.singlenestedpath.test.js | 19 +++++++++++++++++++
 5 files changed, 77 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index 1724dd08be9..cc721b074ee 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -936,6 +936,12 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         if (options.hasOwnProperty('typePojoToMixed')) {
           childSchemaOptions.typePojoToMixed = options.typePojoToMixed;
         }
+        if (this._userProvidedOptions.hasOwnProperty('_id')) {
+          childSchemaOptions._id = this._userProvidedOptions._id;
+        } else if (Schema.Types.DocumentArray.defaultOptions._id != null) {
+          childSchemaOptions._id = Schema.Types.DocumentArray.defaultOptions._id;
+        }
+
         const childSchema = new Schema(cast, childSchemaOptions);
         childSchema.$implicitlyCreated = true;
         return new MongooseTypes.DocumentArray(path, childSchema, obj);
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index d7abd6cea77..dc7f11ec5f8 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -300,6 +300,24 @@ SingleNestedPath.prototype.discriminator = function(name, schema, value) {
   return this.caster.discriminators[name];
 };
 
+/**
+ * Sets a default option for all SingleNestedPath instances.
+ *
+ * ####Example:
+ *
+ *     // Make all numbers have option `min` equal to 0.
+ *     mongoose.Schema.Embedded.set('required', true);
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+SingleNestedPath.set = SchemaType.set;
+
 /*!
  * ignore
  */
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 57e2fa441b0..c263fd66255 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -510,6 +510,24 @@ function scopePaths(array, fields, init) {
   return hasKeys && selected || undefined;
 }
 
+/**
+ * Sets a default option for all DocumentArray instances.
+ *
+ * ####Example:
+ *
+ *     // Make all numbers have option `min` equal to 0.
+ *     mongoose.Schema.DocumentArray.set('_id', false);
+ *
+ * @param {String} option - The option you'd like to set the value for
+ * @param {*} value - value for option
+ * @return {undefined}
+ * @function set
+ * @static
+ * @api public
+ */
+
+DocumentArrayPath.set = SchemaType.set;
+
 /*!
  * Module exports.
  */
diff --git a/test/schema.documentarray.test.js b/test/schema.documentarray.test.js
index 983bf9634de..70d35378510 100644
--- a/test/schema.documentarray.test.js
+++ b/test/schema.documentarray.test.js
@@ -98,4 +98,20 @@ describe('schema.documentarray', function() {
     assert.equal(doc.nested[0].length, 3);
     assert.equal(doc.nested[0][1].title, 'second');
   });
+
+  it('supports `set()` (gh-8883)', function() {
+    mongoose.deleteModel(/Test/);
+    mongoose.Schema.Types.DocumentArray.set('_id', false);
+
+    const Model = mongoose.model('Test', mongoose.Schema({
+      arr: { type: [{ name: String }] }
+    }));
+
+    const doc = new Model({ arr: [{ name: 'test' }] });
+
+    assert.equal(doc.arr.length, 1);
+    assert.ok(!doc.arr[0]._id);
+
+    mongoose.Schema.Types.DocumentArray.set('_id', true);
+  });
 });
diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
index 5365776f587..80f55965ed7 100644
--- a/test/schema.singlenestedpath.test.js
+++ b/test/schema.singlenestedpath.test.js
@@ -143,4 +143,23 @@ describe('SingleNestedPath', function() {
       });
     });
   });
+
+  it('supports `set()` (gh-8883)', function() {
+    mongoose.deleteModel(/Test/);
+    mongoose.Schema.Types.Embedded.set('required', true);
+
+    const Model = mongoose.model('Test', mongoose.Schema({
+      nested: mongoose.Schema({
+        test: String
+      })
+    }));
+
+    const doc = new Model({});
+
+    const err = doc.validateSync();
+    assert.ok(err);
+    assert.ok(err.errors['nested']);
+
+    mongoose.Schema.Types.Embedded.set('required', false);
+  });
 });
\ No newline at end of file

From 93f34245839bbbbc88720dd05bc78560cdc73f2b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 17:15:31 -0400
Subject: [PATCH 0974/2348] fix: fix tests

---
 lib/schema.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index cc721b074ee..b02ec83109f 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -938,7 +938,8 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         }
         if (this._userProvidedOptions.hasOwnProperty('_id')) {
           childSchemaOptions._id = this._userProvidedOptions._id;
-        } else if (Schema.Types.DocumentArray.defaultOptions._id != null) {
+        } else if (Schema.Types.DocumentArray.defaultOptions &&
+            Schema.Types.DocumentArray.defaultOptions._id != null) {
           childSchemaOptions._id = Schema.Types.DocumentArray.defaultOptions._id;
         }
 

From d3858d610648137137fc6340ae88a9694f16a7d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Jun 2020 18:09:24 -0400
Subject: [PATCH 0975/2348] fix: clean up test failures re: #8883

---
 lib/schema.js                     | 1 +
 lib/schema/SingleNestedPath.js    | 2 ++
 lib/schema/documentarray.js       | 2 ++
 test/schema.documentarray.test.js | 2 +-
 test/schema.test.js               | 8 ++++----
 5 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index b02ec83109f..1461a95ac3a 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -936,6 +936,7 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         if (options.hasOwnProperty('typePojoToMixed')) {
           childSchemaOptions.typePojoToMixed = options.typePojoToMixed;
         }
+
         if (this._userProvidedOptions.hasOwnProperty('_id')) {
           childSchemaOptions._id = this._userProvidedOptions._id;
         } else if (Schema.Types.DocumentArray.defaultOptions &&
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index dc7f11ec5f8..5b54e9a86ea 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -316,6 +316,8 @@ SingleNestedPath.prototype.discriminator = function(name, schema, value) {
  * @api public
  */
 
+SingleNestedPath.defaultOptions = {};
+
 SingleNestedPath.set = SchemaType.set;
 
 /*!
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index c263fd66255..81ee5f79405 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -526,6 +526,8 @@ function scopePaths(array, fields, init) {
  * @api public
  */
 
+DocumentArrayPath.defaultOptions = {};
+
 DocumentArrayPath.set = SchemaType.set;
 
 /*!
diff --git a/test/schema.documentarray.test.js b/test/schema.documentarray.test.js
index 70d35378510..89937a538d1 100644
--- a/test/schema.documentarray.test.js
+++ b/test/schema.documentarray.test.js
@@ -112,6 +112,6 @@ describe('schema.documentarray', function() {
     assert.equal(doc.arr.length, 1);
     assert.ok(!doc.arr[0]._id);
 
-    mongoose.Schema.Types.DocumentArray.set('_id', true);
+    mongoose.Schema.Types.DocumentArray.defaultOptions = {};
   });
 });
diff --git a/test/schema.test.js b/test/schema.test.js
index bbb82886605..462ce6c7bee 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2001,13 +2001,13 @@ describe('schema', function() {
       });
 
       assert.equal(schema.childSchemas.length, 2);
-      assert.equal(schema.childSchemas[0].schema, schema1);
-      assert.equal(schema.childSchemas[1].schema, schema2);
+      assert.strictEqual(schema.childSchemas[0].schema, schema1);
+      assert.strictEqual(schema.childSchemas[1].schema, schema2);
 
       schema = schema.clone();
       assert.equal(schema.childSchemas.length, 2);
-      assert.equal(schema.childSchemas[0].schema, schema1);
-      assert.equal(schema.childSchemas[1].schema, schema2);
+      assert.strictEqual(schema.childSchemas[0].schema, schema1);
+      assert.strictEqual(schema.childSchemas[1].schema, schema2);
 
       done();
     });

From eabdccb2e66dda812abdbbcb3b233cd66a79309a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 14 Jun 2020 11:06:48 +0200
Subject: [PATCH 0976/2348] test(model): repro #9131

---
 test/model.test.js | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 01ad32e4f74..9d674f158c5 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6799,10 +6799,44 @@ describe('Model', function() {
       assert.equal(typeof users[0].updatedAt, 'number');
       assert.equal(typeof users[1].updatedAt, 'number');
 
-      // not-lean queries casts to number even if stored on DB as a date
+      // not-lean queries cast to number even if stored on DB as a date
       assert.equal(users[0] instanceof User, false);
       assert.equal(users[1] instanceof User, false);
     });
   });
 
+  it('Model#bulkWrite(...) does not throw an error when provided an empty array (gh-9131)', function() {
+    return co(function*() {
+      const userSchema = new Schema();
+      const User = db.model('User', userSchema);
+
+      const res = yield User.bulkWrite([]);
+
+      assert.deepEqual(
+        res,
+        {
+          result: {
+            ok: 1,
+            writeErrors: [],
+            writeConcernErrors: [],
+            insertedIds: [],
+            nInserted: 0,
+            nUpserted: 0,
+            nMatched: 0,
+            nModified: 0,
+            nRemoved: 0,
+            upserted: []
+          },
+          insertedCount: 0,
+          matchedCount: 0,
+          modifiedCount: 0,
+          deletedCount: 0,
+          upsertedCount: 0,
+          upsertedIds: {},
+          insertedIds: {},
+          n: 0
+        }
+      );
+    });
+  });
 });

From 1ee8bc2303087876ee2d498c95e4cfdc63a378f2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 14 Jun 2020 11:16:42 +0200
Subject: [PATCH 0977/2348] fix(model): allow empty arrays for bulkWrite

---
 lib/helpers/getDefaultBulkwriteResult.js | 27 ++++++++++++++++++++++++
 lib/model.js                             |  6 +++++-
 2 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 lib/helpers/getDefaultBulkwriteResult.js

diff --git a/lib/helpers/getDefaultBulkwriteResult.js b/lib/helpers/getDefaultBulkwriteResult.js
new file mode 100644
index 00000000000..7d10f174864
--- /dev/null
+++ b/lib/helpers/getDefaultBulkwriteResult.js
@@ -0,0 +1,27 @@
+'use strict';
+function getDefaultBulkwriteResult() {
+  return {
+    result: {
+      ok: 1,
+      writeErrors: [],
+      writeConcernErrors: [],
+      insertedIds: [],
+      nInserted: 0,
+      nUpserted: 0,
+      nMatched: 0,
+      nModified: 0,
+      nRemoved: 0,
+      upserted: []
+    },
+    insertedCount: 0,
+    matchedCount: 0,
+    modifiedCount: 0,
+    deletedCount: 0,
+    upsertedCount: 0,
+    upsertedIds: {},
+    insertedIds: {},
+    n: 0
+  };
+}
+
+module.exports = getDefaultBulkwriteResult;
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index 16a1f56f6e6..63eb74c3a15 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -31,6 +31,7 @@ const applyStatics = require('./helpers/model/applyStatics');
 const applyWriteConcern = require('./helpers/schema/applyWriteConcern');
 const assignVals = require('./helpers/populate/assignVals');
 const castBulkWrite = require('./helpers/model/castBulkWrite');
+const getDefaultBulkwriteResult = require('./helpers/getDefaultBulkwriteResult');
 const discriminator = require('./helpers/model/discriminator');
 const each = require('./helpers/each');
 const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
@@ -3493,7 +3494,6 @@ Model.bulkWrite = function(ops, options, callback) {
   const validations = ops.map(op => castBulkWrite(this, op, options));
 
   callback = this.$handleCallbackError(callback);
-
   return promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     each(validations, (fn, cb) => fn(cb), error => {
@@ -3501,6 +3501,10 @@ Model.bulkWrite = function(ops, options, callback) {
         return cb(error);
       }
 
+      if (ops.length === 0) {
+        return cb(null, getDefaultBulkwriteResult());
+      }
+
       this.collection.bulkWrite(ops, options, (error, res) => {
         if (error) {
           return cb(error);

From 21c2c4ef6a1f2725ee33b89f254ba77a6d8da4b2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 14 Jun 2020 13:14:16 -0400
Subject: [PATCH 0978/2348] test(schema): repro #8819

---
 test/schema.singlenestedpath.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
index 5365776f587..620257f2ef0 100644
--- a/test/schema.singlenestedpath.test.js
+++ b/test/schema.singlenestedpath.test.js
@@ -143,4 +143,23 @@ describe('SingleNestedPath', function() {
       });
     });
   });
+
+  it('copies over `requiredValidator` (gh-8819)', function() {
+    const authorSchema = new mongoose.Schema({
+      name: String,
+      pseudonym: String
+    });
+  
+    const bookSchema = new mongoose.Schema({
+      author: {
+        type: authorSchema,
+        required: true
+      }
+    });
+
+    const clone = bookSchema.clone();
+    assert.ok(clone.path('author').requiredValidator);
+    assert.strictEqual(clone.path('author').requiredValidator,
+      clone.path('author').validators[0].validator);
+  });
 });
\ No newline at end of file

From cdd41b1b027c7b33cbfa1211a026e1fc3bdac6c7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 14 Jun 2020 13:14:24 -0400
Subject: [PATCH 0979/2348] fix(schema): copy `requiredValidator` when cloning
 schema with a copy of `validators`

Fix #8819
---
 lib/schema/SingleNestedPath.js | 3 +++
 lib/schema/array.js            | 3 +++
 lib/schema/documentarray.js    | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index d7abd6cea77..a23b7d960a4 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -308,6 +308,9 @@ SingleNestedPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
   const schematype = new this.constructor(this.schema, this.path, options);
   schematype.validators = this.validators.slice();
+  if (this.requiredValidator !== undefined) {
+    schematype.requiredValidator = this.requiredValidator;
+  }
   schematype.caster.discriminators = Object.assign({}, this.caster.discriminators);
   return schematype;
 };
diff --git a/lib/schema/array.js b/lib/schema/array.js
index bc828a178ab..8e7e8cb989d 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -408,6 +408,9 @@ SchemaArray.prototype.clone = function() {
   const options = Object.assign({}, this.options);
   const schematype = new this.constructor(this.path, this.caster, options, this.schemaOptions);
   schematype.validators = this.validators.slice();
+  if (this.requiredValidator !== undefined) {
+    schematype.requiredValidator = this.requiredValidator;
+  }
   return schematype;
 };
 
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 57e2fa441b0..122883c5ff0 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -465,6 +465,9 @@ DocumentArrayPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
   const schematype = new this.constructor(this.path, this.schema, options, this.schemaOptions);
   schematype.validators = this.validators.slice();
+  if (this.requiredValidator !== undefined) {
+    schematype.requiredValidator = this.requiredValidator;
+  }
   schematype.Constructor.discriminators = Object.assign({},
     this.Constructor.discriminators);
   return schematype;

From 075efbd2b4087233c18a5f93db327c4ebc16a36c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 14 Jun 2020 13:18:13 -0400
Subject: [PATCH 0980/2348] style: fix lint

---
 test/schema.singlenestedpath.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/schema.singlenestedpath.test.js b/test/schema.singlenestedpath.test.js
index 620257f2ef0..882749ef267 100644
--- a/test/schema.singlenestedpath.test.js
+++ b/test/schema.singlenestedpath.test.js
@@ -149,7 +149,7 @@ describe('SingleNestedPath', function() {
       name: String,
       pseudonym: String
     });
-  
+
     const bookSchema = new mongoose.Schema({
       author: {
         type: authorSchema,

From 9609e87418b97064adc98bcaa47f85a09d899c06 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 14 Jun 2020 14:07:20 -0400
Subject: [PATCH 0981/2348] feat(document): support `defaults` option to
 disable adding defaults to a single document

Fix #8271
---
 lib/document.js          | 19 ++++++++++++-------
 lib/types/subdocument.js |  5 ++++-
 test/document.test.js    | 21 +++++++++++++++++++++
 3 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index e48c5a2b8b2..9b3c2fe81ac 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -55,7 +55,8 @@ const specialProperties = utils.specialProperties;
  *
  * @param {Object} obj the values to set
  * @param {Object} [fields] optional object containing the fields which were selected in the query returning this document and any populated paths data
- * @param {Boolean} [skipId] bool, should we auto create an ObjectId _id
+ * @param {Object} [options] various configuration options for the document
+ * @param {Boolean} [options.defaults=true] if `false`, skip applying default values to this document.
  * @inherits NodeJS EventEmitter http://nodejs.org/api/events.html#events_class_events_eventemitter
  * @event `init`: Emitted on a document after it has been retrieved from the db and fully hydrated by Mongoose.
  * @event `save`: Emitted when the document is successfully saved
@@ -67,7 +68,9 @@ function Document(obj, fields, skipId, options) {
     options = skipId;
     skipId = options.skipId;
   }
-  options = options || {};
+  options = Object.assign({}, options);
+  const defaults = get(options, 'defaults', true);
+  options.defaults = defaults;
 
   // Support `browserDocument.js` syntax
   if (this.schema == null) {
@@ -126,9 +129,11 @@ function Document(obj, fields, skipId, options) {
 
     // By default, defaults get applied **before** setting initial values
     // Re: gh-6155
-    $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, true, {
-      isNew: this.isNew
-    });
+    if (defaults) {
+      $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, true, {
+        isNew: this.isNew
+      });
+    }
   }
 
   if (obj) {
@@ -147,13 +152,13 @@ function Document(obj, fields, skipId, options) {
   // Function defaults get applied **after** setting initial values so they
   // see the full doc rather than an empty one, unless they opt out.
   // Re: gh-3781, gh-6155
-  if (options.willInit) {
+  if (options.willInit && defaults) {
     EventEmitter.prototype.once.call(this, 'init', () => {
       $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
         isNew: this.isNew
       });
     });
-  } else {
+  } else if (defaults) {
     $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
       isNew: this.isNew
     });
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 521237aee72..63cd42c0c11 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -29,7 +29,10 @@ function Subdocument(value, fields, parent, skipId, options) {
   }
   if (parent != null) {
     // If setting a nested path, should copy isNew from parent re: gh-7048
-    options = Object.assign({}, options, { isNew: parent.isNew });
+    options = Object.assign({}, options, {
+      isNew: parent.isNew,
+      defaults: parent.$__.$options.defaults
+    });
   }
   Document.call(this, value, fields, skipId, options);
 
diff --git a/test/document.test.js b/test/document.test.js
index 9983736d38a..8d3f6bcae64 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8975,4 +8975,25 @@ describe('document', function() {
     const axl = new Person({ fullName: 'Axl Rose' });
     assert.equal(axl.fullName, 'Axl Rose');
   });
+
+  it('supports skipping defaults on a document (gh-8271)', function() {
+    const testSchema = new mongoose.Schema({
+      testTopLevel: { type: String, default: 'foo' },
+      testNested: {
+        prop: { type: String, default: 'bar' }
+      },
+      testArray: [{ prop: { type: String, defualt: 'baz' } }],
+      testSingleNested: new Schema({
+        prop: { type: String, default: 'qux' }
+      })
+    });
+    const Test = db.model('Test', testSchema);
+
+    const doc = new Test({ testArray: [{}], testSingleNested: {} }, null,
+      { defaults: false });
+    assert.ok(!doc.testTopLevel);
+    assert.ok(!doc.testNested.prop);
+    assert.ok(!doc.testArray[0].prop);
+    assert.ok(!doc.testSingleNested.prop);
+  });
 });

From 24f6a29281498d9e7b4d7e61c8a167f5f20ee66e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 14 Jun 2020 14:40:45 -0400
Subject: [PATCH 0982/2348] feat(aggregate): add `Aggregate#search()` for Atlas
 Text Search

Fix #9115
---
 lib/aggregate.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index cc31f09b98d..d275c2ed4da 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -909,6 +909,32 @@ Aggregate.prototype.facet = function(options) {
   return this.append({ $facet: options });
 };
 
+/**
+ * Helper for [Atlas Text Search](https://docs.atlas.mongodb.com/reference/atlas-search/tutorial/)'s
+ * `$search` stage.
+ *
+ * ####Example:
+ *
+ *     Model.aggregate().
+ *      search({
+ *        text: {
+ *          query: 'baseball',
+ *          path: 'plot'
+ *        }
+ *      });
+ *
+ *     // Output: [{ plot: '...', title: '...' }]
+ *
+ * @param {Object} $search options
+ * @return {Aggregate} this
+ * @see $search https://docs.atlas.mongodb.com/reference/atlas-search/tutorial/
+ * @api public
+ */
+
+Aggregate.prototype.search = function(options) {
+  return this.append({ $search: options });
+};
+
 /**
  * Returns the current pipeline
  *

From d7f10689e7095945b537fd01a5bc32ffc5ea5eed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Jun 2020 11:24:40 -0400
Subject: [PATCH 0983/2348] chore: release 5.9.19

---
 History.md   | 16 ++++++++++++++++
 package.json |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index abc5cc12655..4215c6aab93 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,19 @@
+5.9.19 / 2020-06-15
+===================
+ * fix: upgrade mongodb driver -> 3.5.9 #9124 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix: copy `required` validator on single nested subdoc correctly when calling `Schema#clone()` #8819
+ * fix(discriminator): handle `tiedValue` when casting update on nested paths #9108
+ * fix(model): allow empty arrays for bulkWrite #9132 #9131 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(schema): correctly set partialFilterExpression for nested schema indexes #9091
+ * fix(castArrayFilters): handle casting on all fields of array filter #9122 [lafeuil](https://github.com/lafeuil)
+ * fix(update): handle nested path createdAt when overwriting parent path #9105
+ * docs(subdocs): add some notes on the difference between single nested subdocs and nested paths #9085
+ * docs(subdocs): improve docs on `typePojoToMixed` #9085
+ * docs: add note about connections in `globalSetup` with Jest #9063
+ * docs: add schema and how to set default sub-schema to schematype options #9111 [dfle](https://github.com/dfle)
+ * docs(index): use `const` instead of `var` in examples #9125 [dmcgrouther](https://github.com/dmcgrouther)
+ * docs: corrected markdown typo #9117
+
 5.9.18 / 2020-06-05
 ===================
  * fix: improve atlas error in the event of incorrect password #9095
diff --git a/package.json b/package.json
index a719c94ab89..b99db2db5c1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.18",
+  "version": "5.9.19",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 78f5dbb18ab84b42df6e409a078c8d75f4c99d31 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Jun 2020 14:43:26 -0400
Subject: [PATCH 0984/2348] test: fix tests re: #9097

---
 lib/helpers/setDefaultsOnInsert.js | 2 +-
 test/index.test.js                 | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/setDefaultsOnInsert.js b/lib/helpers/setDefaultsOnInsert.js
index 747cb61ab8d..b061a8d1759 100644
--- a/lib/helpers/setDefaultsOnInsert.js
+++ b/lib/helpers/setDefaultsOnInsert.js
@@ -17,7 +17,7 @@ module.exports = function(filter, schema, castedDoc, options) {
   options = options || {};
 
   const shouldSetDefaultsOnInsert =
-    options.hasOwnProperty('setDefaultsOnInsert') ?
+    options.setDefaultsOnInsert != null ?
       options.setDefaultsOnInsert :
       schema.base.options.setDefaultsOnInsert;
 
diff --git a/test/index.test.js b/test/index.test.js
index 993d69f78b5..b50577bc512 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -766,7 +766,7 @@ describe('mongoose module:', function() {
         }, { collection: 'movies_1' });
 
         const Movie = db.model('Movie', schema);
-
+        yield Movie.deleteMany({});
 
         yield Movie.updateOne(
           {},

From 688d19d4c923c1ca2f83ec4b72795798fd7fc84d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Jun 2020 15:48:34 -0400
Subject: [PATCH 0985/2348] feat(connection): make `transaction()` reset
 versionKey if transaction fails

Re: #8380
---
 lib/connection.js               | 11 ++++++++---
 lib/plugins/trackTransaction.js | 17 ++++++++++++-----
 test/docs/transactions.test.js  | 22 ++++++++++++++++++++++
 3 files changed, 42 insertions(+), 8 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index e5b3187154b..73d71780fed 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -452,7 +452,7 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
 
 Connection.prototype.transaction = function transaction(fn) {
   return this.startSession().then(session => {
-    session[sessionNewDocuments] = [];
+    session[sessionNewDocuments] = new Map();
     return session.withTransaction(() => fn(session)).
       then(res => {
         delete session[sessionNewDocuments];
@@ -461,8 +461,13 @@ Connection.prototype.transaction = function transaction(fn) {
       catch(err => {
         // If transaction was aborted, we need to reset newly
         // inserted documents' `isNew`.
-        for (const doc of session[sessionNewDocuments]) {
-          doc.isNew = true;
+        for (const [doc, state] of session[sessionNewDocuments].entries()) {
+          if (state.hasOwnProperty('isNew')) {
+            doc.isNew = state.isNew;
+          }
+          if (state.hasOwnProperty('versionKey')) {
+            doc.set(doc.schema.options.versionKey, state.versionKey);
+          }
         }
         delete session[sessionNewDocuments];
         throw err;
diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index c307f9b759a..52d9d231f67 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -4,10 +4,6 @@ const sessionNewDocuments = require('../helpers/symbols').sessionNewDocuments;
 
 module.exports = function trackTransaction(schema) {
   schema.pre('save', function() {
-    if (!this.isNew) {
-      return;
-    }
-
     const session = this.$session();
     if (session == null) {
       return;
@@ -15,6 +11,17 @@ module.exports = function trackTransaction(schema) {
     if (session.transaction == null || session[sessionNewDocuments] == null) {
       return;
     }
-    session[sessionNewDocuments].push(this);
+
+    if (!session[sessionNewDocuments].has(this)) {
+      const initialState = {};
+      if (this.isNew) {
+        initialState.isNew = true;
+      }
+      if (this.schema.options.versionKey) {
+        initialState.versionKey = this.get(this.schema.options.versionKey);
+      }
+
+      session[sessionNewDocuments].set(this, initialState);
+    }
   });
 };
\ No newline at end of file
diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index 73daab51e83..8d66c775fc3 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -10,6 +10,7 @@ const Schema = mongoose.Schema;
 describe('transactions', function() {
   let db;
   let _skipped = false;
+  this.timeout(10000);
 
   before(function() {
     if (!process.env.REPLICA_SET) {
@@ -382,4 +383,25 @@ describe('transactions', function() {
       assert.ok(doc.isNew);
     });
   });
+
+  it('can save document after aborted transaction (gh-8380)', function() {
+    return co(function*() {
+      const schema = Schema({ name: String, arr: [String] });
+
+      const Test = db.model('gh8380', schema);
+
+      yield Test.createCollection();
+      yield Test.create({ name: 'foo', arr: ['bar'] });
+      const doc = yield Test.findOne();
+      yield db.
+        transaction(session => co(function*() {
+          doc.arr.pop();
+          yield doc.save({ session });
+          throw new Error('Oops');
+        })).
+        catch(err => assert.equal(err.message, 'Oops'));
+      doc.set('arr.0', 'qux');
+      yield doc.save();
+    });
+  });
 });

From e98b2f7a23bfaddeda31b50203e0d6d6b3abd243 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Jun 2020 15:51:33 -0400
Subject: [PATCH 0986/2348] test: fix tests for node v4 and v6

---
 lib/connection.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 73d71780fed..a06e44dfd1f 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -461,7 +461,8 @@ Connection.prototype.transaction = function transaction(fn) {
       catch(err => {
         // If transaction was aborted, we need to reset newly
         // inserted documents' `isNew`.
-        for (const [doc, state] of session[sessionNewDocuments].entries()) {
+        for (const doc of session[sessionNewDocuments].keys()) {
+          const state = session[sessionNewDocuments].get(doc);
           if (state.hasOwnProperty('isNew')) {
             doc.isNew = state.isNew;
           }

From 8437d2bf90ba0b9823ac8e9bddbbaa7e4ff13f1b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Jun 2020 15:58:28 -0400
Subject: [PATCH 0987/2348] chore: update opencollective sponsors

---
 index.pug | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.pug b/index.pug
index 240258cb827..8b4a4490b54 100644
--- a/index.pug
+++ b/index.pug
@@ -238,8 +238,8 @@ html(lang='en')
               <a href="https://ghostinspector.com/">
                 <img class="sponsor" src="https://images.opencollective.com/ghostinspector/51b7be8/logo.png" style="height: 100px">
               </a>
-              <a href="https://moneypug.co.uk/">
-                <img class="sponsor" src="https://images.opencollective.com/moneypug/45f8d53/logo.png" style="height: 100px">
+              <a href="https://wongagames.co.uk/">
+                <img class="sponsor" src="https://images.opencollective.com/wongagames/d3eb92f/logo/256.png" style="height: 100px">
               </a>
               <a href="https://medium.com/@niksundin/best-web-design-companies-1872e445775f">
                 <img class="sponsor" src="https://images.opencollective.com/top-web-design-agencies/d92d747/logo.png" style="height: 100px">

From b606888b30c431c4862c1f602498e5531fbde4d7 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Mon, 15 Jun 2020 13:45:51 -0700
Subject: [PATCH 0988/2348] docs: specify the array field syntax for invalidate

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index e48c5a2b8b2..a0b6b1284b8 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2561,7 +2561,7 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
  *               value: 14 } } }
  *     })
  *
- * @param {String} path the field to invalidate
+ * @param {String} path the field to invalidate. For array elements, use the `array.X.field` syntax, where `X` is the 0-based index in the array.
  * @param {String|Error} errorMsg the error which states the reason `path` was invalid
  * @param {Object|String|Number|any} value optional invalid value
  * @param {String} [kind] optional `kind` property for the error

From 27ccea6f44de89e6d8809557a5a933009ebd86a7 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Mon, 15 Jun 2020 17:05:12 -0700
Subject: [PATCH 0989/2348] docs: array field notation for invalidate

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index a0b6b1284b8..3e0e42cc1ef 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2561,7 +2561,7 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
  *               value: 14 } } }
  *     })
  *
- * @param {String} path the field to invalidate. For array elements, use the `array.X.field` syntax, where `X` is the 0-based index in the array.
+ * @param {String} path the field to invalidate. For array elements, use the `array.i.field` syntax, where `i` is the 0-based index in the array.
  * @param {String|Error} errorMsg the error which states the reason `path` was invalid
  * @param {Object|String|Number|any} value optional invalid value
  * @param {String} [kind] optional `kind` property for the error

From 30618066d6e57ef4d9a382d214dfd90e1962f9e2 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Wed, 17 Jun 2020 19:12:17 -0700
Subject: [PATCH 0990/2348] docs: minor English fix in Validation

---
 test/docs/validation.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 9d75589a498..a82af5fed02 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -493,7 +493,7 @@ describe('validation docs', function() {
   });
 
   /**
-   * The other key difference that update validators only run on the paths
+   * The other key difference is that update validators only run on the paths
    * specified in the update. For instance, in the below example, because
    * 'name' is not specified in the update operation, update validation will
    * succeed.

From df6856b30f13886db979af68d582b082bbaa3380 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Wed, 17 Jun 2020 19:20:39 -0700
Subject: [PATCH 0991/2348] docs(validation): add validateBeforeSave and
 invalidate

---
 test/docs/validation.test.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 9d75589a498..5e4a874e1dd 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -23,7 +23,9 @@ describe('validation docs', function() {
    *
    * - Validation is defined in the [SchemaType](./schematypes.html)
    * - Validation is [middleware](./middleware.html). Mongoose registers validation as a `pre('save')` hook on every schema by default.
+   * - You can disable automatic validation before save by setting the [validateBeforeSave](./guide.html#validateBeforeSave) option
    * - You can manually run validation using `doc.validate(callback)` or `doc.validateSync()`
+   * - You can manually mark a field as invalid (causing validation to fail) by using [`doc.invalidate(...)`](./api.html#document_Document-invalidate)
    * - Validators are not run on undefined values. The only exception is the [`required` validator](./api.html#schematype_SchemaType-required).
    * - Validation is asynchronously recursive; when you call [Model#save](./api.html#model_Model-save), sub-document validation is executed as well. If an error occurs, your [Model#save](./api.html#model_Model-save) callback receives it
    * - Validation is customizable

From 1ed1eb106835364a7da01829a8d839abf4a7b40a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Jun 2020 10:35:50 -0400
Subject: [PATCH 0992/2348] fix(connection): make sure to close previous
 connection when calling `openUri()` on an already open connection

Fix #9107
---
 lib/connection.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index c64e192c1f9..b7aaf2f7016 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -707,6 +707,10 @@ Connection.prototype.openUri = function(uri, options, callback) {
   };
 
   const promise = new Promise((resolve, reject) => {
+    if (_this.client != null) {
+      _this.client.close();
+    }
+
     const client = new mongodb.MongoClient(uri, options);
     _this.client = client;
     client.connect(function(error) {

From 5253b501f181430a4076019c13540bf70ee1c980 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 20 Jun 2020 11:56:43 -0400
Subject: [PATCH 0993/2348] test(populate): repro #9148

---
 test/model.populate.test.js | 48 +++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6f8e07899f6..a5be1bc1d51 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9429,4 +9429,52 @@ describe('model: populate:', function() {
       assert.equal(foundOffice.place.building.owner, 'test');
     });
   });
+
+  it('handles populating primitive array under document array with discriminator (gh-9148)', function() {
+    const ContentSchema = new Schema({ name: String });
+    const Content = db.model('Test1', ContentSchema);
+
+    const DataSchema = new Schema({ alias: String }, {
+      discriminatorKey: 'type',
+      _id: false
+    });
+    const ContentRelationSchema = new Schema({
+      content: [{ type: Schema.Types.ObjectId, ref: 'Test1' }]
+    }, { _id: false });
+    const PageSchema = new Schema({
+      name: String,
+      data: [DataSchema]
+    });
+
+    PageSchema.path('data').discriminator('content', ContentRelationSchema);
+    const Page = db.model('Test', PageSchema);
+
+    return co(function*() {
+      const content = yield Promise.all([
+        Content.create({ name: 'A' }),
+        Content.create({ name: 'B' }),
+      ]);
+
+      const doc = yield Page.create({
+        name: 'Index',
+        data: [{
+          alias: 'my_content',
+          type: 'content',
+          content: [content[0]._id, content[1]._id]
+        }]
+      });
+
+      const page = yield Page.findById(doc._id).populate({
+        path: 'data.content',
+        select: { name: 1, _id: 0 }
+      });
+      assert.ok(Array.isArray(page.data[0].content));
+      console.log('Foo', page.data)
+      assert.deepEqual(page.toObject().data, [{
+        alias: 'my_content',
+        type: 'content',
+        content: [{ name: 'A' }, { name: 'B' }]
+      }]);
+    });
+  });
 });

From 666aade8e25969b2c76e9910f185d4c300a6e1d2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 20 Jun 2020 11:56:53 -0400
Subject: [PATCH 0994/2348] fix(populate): handle populating primitive array
 under document array discriminator

Fix #9148
---
 lib/helpers/populate/getModelsMapForPopulate.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index b012f4e7cdd..3c81d46d2ae 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -166,7 +166,9 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       }
     } else if (schema && !schema[schemaMixedSymbol]) {
       // Skip Mixed types because we explicitly don't do casting on those.
-      justOne = !schema.$isMongooseArray;
+      justOne = Array.isArray(schema) ?
+        schema.every(schema => !schema.$isMongooseArray) :
+        !schema.$isMongooseArray;
     }
 
     if (!modelNames) {

From 551fc9ef0e1795e9ec8cbb844480521942dbbb79 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 20 Jun 2020 12:04:53 -0400
Subject: [PATCH 0995/2348] style: fix lint

---
 test/model.populate.test.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a5be1bc1d51..b582d3ea284 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9452,7 +9452,7 @@ describe('model: populate:', function() {
     return co(function*() {
       const content = yield Promise.all([
         Content.create({ name: 'A' }),
-        Content.create({ name: 'B' }),
+        Content.create({ name: 'B' })
       ]);
 
       const doc = yield Page.create({
@@ -9469,7 +9469,6 @@ describe('model: populate:', function() {
         select: { name: 1, _id: 0 }
       });
       assert.ok(Array.isArray(page.data[0].content));
-      console.log('Foo', page.data)
       assert.deepEqual(page.toObject().data, [{
         alias: 'my_content',
         type: 'content',

From 2ec166f5a56748dee265c39321fb41618978a77a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 21 Jun 2020 10:53:23 +0200
Subject: [PATCH 0996/2348] test: repro #9157

---
 test/model.test.js | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 9d674f158c5..6f2632f5197 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6805,7 +6805,7 @@ describe('Model', function() {
     });
   });
 
-  it('Model#bulkWrite(...) does not throw an error when provided an empty array (gh-9131)', function() {
+  it('Model.bulkWrite(...) does not throw an error when provided an empty array (gh-9131)', function() {
     return co(function*() {
       const userSchema = new Schema();
       const User = db.model('User', userSchema);
@@ -6839,4 +6839,33 @@ describe('Model', function() {
       );
     });
   });
+
+  it('Model.bulkWrite(...) does not throw an error with upsert:true, setDefaultsOnInsert: true (gh-9157)', function() {
+    return co(function*() {
+      const userSchema = new Schema(
+        {
+          friends: [String],
+          age: { type: Number, default: 25 }
+        },
+        { timestamps: true }
+      );
+      const User = db.model('User', userSchema);
+
+      yield User.bulkWrite([
+        {
+          updateOne: {
+            filter: { },
+            update: { friends: ['Sam'] },
+            upsert: true,
+            setDefaultsOnInsert: true
+          }
+        }
+      ]);
+
+      const user = yield User.findOne().sort({ _id: -1 });
+
+      assert.equal(user.age, 25);
+      assert.deepEqual(user.friends, ['Sam']);
+    });
+  });
 });

From 5afb82fc8eb57fcd50a2faf7f14ba82aad5b90d4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 21 Jun 2020 10:58:00 +0200
Subject: [PATCH 0997/2348] fix(model): fix conflicting $setOnInsert default
 values with `update` values in bulkWrite

---
 lib/helpers/setDefaultsOnInsert.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/setDefaultsOnInsert.js b/lib/helpers/setDefaultsOnInsert.js
index 0545e80d3d4..9f7eef09cb9 100644
--- a/lib/helpers/setDefaultsOnInsert.js
+++ b/lib/helpers/setDefaultsOnInsert.js
@@ -95,7 +95,9 @@ module.exports = function(filter, schema, castedDoc, options) {
       if (!isModified(modified, path) && typeof def !== 'undefined') {
         castedDoc = castedDoc || {};
         castedDoc.$setOnInsert = castedDoc.$setOnInsert || {};
-        castedDoc.$setOnInsert[path] = def;
+        if (!castedDoc[path]) {
+          castedDoc.$setOnInsert[path] = def;
+        }
         updatedValues[path] = def;
       }
     }

From 999da5a7dd401294e7b6fcfaaa441619b88d65ab Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 21 Jun 2020 11:41:29 -0400
Subject: [PATCH 0998/2348] fix(model): respect `autoIndex: false` on nested
 schemas

Re: #9150
---
 lib/helpers/schema/getIndexes.js | 1 +
 lib/model.js                     | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index 52a275ee607..e0c8cd2075d 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -83,6 +83,7 @@ module.exports = function getIndexes(schema) {
         if (!('background' in options)) {
           options.background = true;
         }
+        options._autoIndex = schema.options.autoIndex;
 
         const indexName = options && options.name;
         if (typeof indexName === 'string') {
diff --git a/lib/model.js b/lib/model.js
index 63eb74c3a15..d82239de298 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1612,6 +1612,9 @@ function _ensureIndexes(model, options, callback) {
     if (!index) {
       return done();
     }
+    if (options._automatic && index[1]._autoIndex === false) {
+      return create();
+    }
 
     if (baseSchemaIndexes.find(i => utils.deepEqual(i, index))) {
       return create();
@@ -1619,6 +1622,7 @@ function _ensureIndexes(model, options, callback) {
 
     const indexFields = utils.clone(index[0]);
     const indexOptions = utils.clone(index[1]);
+    delete indexOptions._autoIndex;
 
     _decorateDiscriminatorIndexOptions(model, indexOptions);
     if ('safe' in options) {

From 58f3376b8d80e74eb24ed3d5804fcdfd60f1769a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 21 Jun 2020 11:47:11 -0400
Subject: [PATCH 0999/2348] test: add test for #9150

---
 test/model.indexes.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 89b3db7d981..43547aff57e 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -470,6 +470,28 @@ describe('model', function() {
       });
   });
 
+  it('skips automatic indexing on childSchema if autoIndex: false (gh-9150)', function() {
+    const nestedSchema = mongoose.Schema({
+      name: { type: String, index: true }
+    }, { autoIndex: false });
+    const schema = mongoose.Schema({
+      nested: nestedSchema,
+      top: { type: String, index: true }
+    });
+    let Model;
+
+    return Promise.resolve().
+      then(() => {
+        Model = db.model('Model', schema);
+        return Model.init();
+      }).
+      then(() => Model.listIndexes()).
+      then(indexes => {
+        assert.equal(indexes.length, 2);
+        assert.deepEqual(indexes[1].key, { top: 1 });
+      });
+  });
+
   describe('discriminators with unique', function() {
     this.timeout(5000);
 

From b364a8dc4a0b390faf9c01d55cd8e8ab86b9a67d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 22 Jun 2020 12:10:57 +0200
Subject: [PATCH 1000/2348] allow non-null falsy values for setDefaultsOnInsert

---
 lib/helpers/setDefaultsOnInsert.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/setDefaultsOnInsert.js b/lib/helpers/setDefaultsOnInsert.js
index 9f7eef09cb9..9c6986ddef6 100644
--- a/lib/helpers/setDefaultsOnInsert.js
+++ b/lib/helpers/setDefaultsOnInsert.js
@@ -1,6 +1,6 @@
 'use strict';
-
 const modifiedPaths = require('./common').modifiedPaths;
+const get = require('./get');
 
 /**
  * Applies defaults to update and findOneAndUpdate operations.
@@ -95,7 +95,7 @@ module.exports = function(filter, schema, castedDoc, options) {
       if (!isModified(modified, path) && typeof def !== 'undefined') {
         castedDoc = castedDoc || {};
         castedDoc.$setOnInsert = castedDoc.$setOnInsert || {};
-        if (!castedDoc[path]) {
+        if (get(castedDoc, path) == null) {
           castedDoc.$setOnInsert[path] = def;
         }
         updatedValues[path] = def;

From e47531ad1b864708e7241530031800c5aee41bd9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Jun 2020 17:18:47 -0400
Subject: [PATCH 1001/2348] test: fix tests

---
 lib/helpers/schema/getIndexes.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/schema/getIndexes.js b/lib/helpers/schema/getIndexes.js
index e0c8cd2075d..be907dbd647 100644
--- a/lib/helpers/schema/getIndexes.js
+++ b/lib/helpers/schema/getIndexes.js
@@ -83,7 +83,9 @@ module.exports = function getIndexes(schema) {
         if (!('background' in options)) {
           options.background = true;
         }
-        options._autoIndex = schema.options.autoIndex;
+        if (schema.options.autoIndex != null) {
+          options._autoIndex = schema.options.autoIndex;
+        }
 
         const indexName = options && options.name;
         if (typeof indexName === 'string') {

From 3251f72bd8ea15465ed891ffc3c5f70d33198121 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Jun 2020 17:23:41 -0400
Subject: [PATCH 1002/2348] chore: release 5.9.20

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 4215c6aab93..46818236721 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.9.20 / 2020-06-22
+===================
+ * fix(populate): handle populating primitive array under document array discriminator #9148
+ * fix(connection): make sure to close previous connection when calling `openUri()` on an already open connection #9107
+ * fix(model): fix conflicting $setOnInsert default values with `update` values in bulkWrite #9160 #9157 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(validation): add note about validateBeforeSave and invalidate #9144 [dandv](https://github.com/dandv)
+ * docs: specify the array field syntax for invalidate #9137 [dandv](https://github.com/dandv)
+ * docs: fix several typos and broken references #9024 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs: fix minor typo #9143 [dandv](https://github.com/dandv)
+
 5.9.19 / 2020-06-15
 ===================
  * fix: upgrade mongodb driver -> 3.5.9 #9124 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index b99db2db5c1..d40aadaaadd 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.19",
+  "version": "5.9.20",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 04afc5dd05b979e93d7afbb2a7e30231c8d4a702 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 25 Jun 2020 14:44:17 -0400
Subject: [PATCH 1003/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 8b4a4490b54..0f79603fb2f 100644
--- a/index.pug
+++ b/index.pug
@@ -364,6 +364,9 @@ html(lang='en')
               <a href="https://www.japanesecasino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/japanesecasino/b0ffe3c/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.parhaatkasinot.com/">
+                <img class="sponsor" src="https://images.opencollective.com/parhaatkasinot/e7fda21/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From e5617db9eed1dd0b75cebbade97c337219aab07f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 25 Jun 2020 23:45:58 +0200
Subject: [PATCH 1004/2348] remove unused arguments from
 `applySchemaTypeTransforms`

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 3e0e42cc1ef..1c0ba365855 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3075,7 +3075,7 @@ Document.prototype.$toObject = function(options, json) {
   // we need to adjust options.transform to be the child schema's transform and
   // not the parent schema's
   if (transform) {
-    applySchemaTypeTransforms(this, ret, gettersOptions, options);
+    applySchemaTypeTransforms(this, ret);
   }
 
   if (transform === true || (schemaOptions.toObject && transform)) {

From ea7ecf3f1daf3c9b7286ce97ec0fcdcb080d8f98 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 26 Jun 2020 00:10:51 +0200
Subject: [PATCH 1005/2348] test: repro #9163

---
 test/document.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 9983736d38a..bb521b8a46e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8975,4 +8975,26 @@ describe('document', function() {
     const axl = new Person({ fullName: 'Axl Rose' });
     assert.equal(axl.fullName, 'Axl Rose');
   });
+
+  it('throws an error when `transform` returns a promise (gh-9163)', function() {
+    const userSchema = new Schema({
+      name: {
+        type: String,
+        transform: function() {
+          return new Promise(() => {});
+        }
+      }
+    });
+
+    const User = mongoose.model('User', userSchema);
+
+    const user = new User({ name: 'Hafez' });
+    assert.throws(function() {
+      user.toJSON();
+    }, /`transform` option has to be synchronous, but is returning a promise on path `name`./);
+
+    assert.throws(function() {
+      user.toObject();
+    }, /`transform` option has to be synchronous, but is returning a promise on path `name`./);
+  });
 });

From a29b9609a0db84011936b27ed095fea2b048c30b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 26 Jun 2020 00:13:39 +0200
Subject: [PATCH 1006/2348] fix(document): disallow `transform` functions that
 return promises

---
 lib/document.js          | 15 +++++++++++++--
 lib/helpers/isPromise.js |  6 ++++++
 2 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 lib/helpers/isPromise.js

diff --git a/lib/document.js b/lib/document.js
index 1c0ba365855..b3c41c10c3d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -31,6 +31,7 @@ const inspect = require('util').inspect;
 const internalToObjectOptions = require('./options').internalToObjectOptions;
 const mpath = require('mpath');
 const utils = require('./utils');
+const isPromise = require('./helpers/isPromise');
 
 const clone = utils.clone;
 const deepEqual = utils.deepEqual;
@@ -3414,13 +3415,17 @@ function applySchemaTypeTransforms(self, json) {
     const schematype = schema.paths[path];
     if (typeof schematype.options.transform === 'function') {
       const val = self.get(path);
-      json[path] = schematype.options.transform.call(self, val);
+      const transformedValue = schematype.options.transform.call(self, val);
+      throwErrorIfPromise(path, transformedValue);
+      json[path] = transformedValue;
     } else if (schematype.$embeddedSchemaType != null &&
         typeof schematype.$embeddedSchemaType.options.transform === 'function') {
       const vals = [].concat(self.get(path));
       const transform = schematype.$embeddedSchemaType.options.transform;
       for (let i = 0; i < vals.length; ++i) {
-        vals[i] = transform.call(self, vals[i]);
+        const transformedValue = transform.call(self, vals[i]);
+        vals[i] = transformedValue;
+        throwErrorIfPromise(path, transformedValue);
       }
 
       json[path] = vals;
@@ -3430,6 +3435,12 @@ function applySchemaTypeTransforms(self, json) {
   return json;
 }
 
+function throwErrorIfPromise(path, transformedValue) {
+  if (isPromise(transformedValue)) {
+    throw new Error('`transform` option has to be synchronous, but is returning a promise on path `' + path + '`.');
+  }
+}
+
 /**
  * The return value of this method is used in calls to JSON.stringify(doc).
  *
diff --git a/lib/helpers/isPromise.js b/lib/helpers/isPromise.js
new file mode 100644
index 00000000000..d6db2608cc9
--- /dev/null
+++ b/lib/helpers/isPromise.js
@@ -0,0 +1,6 @@
+'use strict';
+function isPromise(val) {
+  return !!val && (typeof val === 'object' || typeof val === 'function') && typeof val.then === 'function';
+}
+
+module.exports = isPromise;
\ No newline at end of file

From 05bbdd6d9af789a8a08b63ae329cd9a3cf4e131d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 26 Jun 2020 00:53:08 +0200
Subject: [PATCH 1007/2348] fix tests re #9163

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index bb521b8a46e..ff875ce1b83 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8986,7 +8986,7 @@ describe('document', function() {
       }
     });
 
-    const User = mongoose.model('User', userSchema);
+    const User = db.model('User', userSchema);
 
     const user = new User({ name: 'Hafez' });
     assert.throws(function() {

From fb424e8376867b9c90669ba2933e7b0e93127506 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 28 Jun 2020 11:41:01 -0400
Subject: [PATCH 1008/2348] test(document): repro #9165

---
 test/document.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 9983736d38a..8020a362b36 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8975,4 +8975,18 @@ describe('document', function() {
     const axl = new Person({ fullName: 'Axl Rose' });
     assert.equal(axl.fullName, 'Axl Rose');
   });
+
+  it('uses strict equality when checking mixed paths for modifications (gh-9165)', function() {
+    const schema = Schema({ obj: {} });
+    const Model = db.model('gh9165', schema);
+
+    return Model.create({ obj: { key: '2' } }).
+      then(doc => {
+        doc.obj = { key: 2 };
+        assert.ok(doc.modifiedPaths().indexOf('obj') !== -1);
+        return doc.save();
+      }).
+      then(doc => Model.findById(doc)).
+      then(doc => assert.strictEqual(doc.obj.key, 2));
+  });
 });

From 7e064f9535ca5d71cc78577d52850c4469a88375 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 28 Jun 2020 11:41:10 -0400
Subject: [PATCH 1009/2348] fix(document): use strict equality when checking
 mixed paths for modifications

Fix #9165
---
 lib/types/documentarray.js | 2 +-
 lib/utils.js               | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index b5ebbeb8ac0..0ae4ed03a29 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -150,7 +150,7 @@ class CoreDocumentArray extends CoreMongooseArray {
           return val;
         }
       } else if (!(id instanceof ObjectId) && !(_id instanceof ObjectId)) {
-        if (utils.deepEqual(id, _id)) {
+        if (id == _id || utils.deepEqual(id, _id)) {
           return val;
         }
       } else if (casted == _id) {
diff --git a/lib/utils.js b/lib/utils.js
index 23411ee2275..fceaec681e3 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -79,7 +79,7 @@ exports.deepEqual = function deepEqual(a, b) {
   }
 
   if (typeof a !== 'object' && typeof b !== 'object') {
-    return a == b;
+    return a === b;
   }
 
   if (a === null || b === null || a === undefined || b === undefined) {

From f888f4cf55657f606dd0015ce1bafd82169de435 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Ritter?= <ritterjv@gmail.com>
Date: Mon, 29 Jun 2020 17:27:00 -0400
Subject: [PATCH 1010/2348] Update schema.js

---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 062b5be8321..8c9f6e70009 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -509,7 +509,7 @@ Schema.prototype.add = function add(obj, prefix) {
         // Propage `typePojoToMixed` to implicitly created schemas
         const opts = { typePojoToMixed: false };
         const _schema = new Schema(obj[key][this.options.typeKey], opts);
-        const schemaWrappedPath = Object.assign({}, obj[key], { type: _schema });
+        const schemaWrappedPath = Object.assign({}, obj[key], { [this.options.typeKey]: _schema });
         this.path(prefix + key, schemaWrappedPath);
       } else {
         // Either the type is non-POJO or we interpret it as Mixed anyway

From 1c8f56590b8f5ba9418876d4410afd2782ca6592 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 10:26:35 -0400
Subject: [PATCH 1011/2348] test(populate): repro #9175

---
 test/model.populate.test.js | 38 +++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index b582d3ea284..2b1cbd68bf4 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9476,4 +9476,42 @@ describe('model: populate:', function() {
       }]);
     });
   });
+
+  it('handles deselecting _id with `perDocumentLimit` (gh-8460) (gh-9175)', function() {
+    const postSchema = new Schema({
+      title: String,
+      commentsIds: [{ type: Schema.ObjectId, ref: 'Comment' }]
+    });
+    const Post = db.model('Post', postSchema);
+  
+    const commentSchema = new Schema({ content: String });
+    const Comment = db.model('Comment', commentSchema);
+
+    return co(function*() {
+      const post1 = new Post({ title: 'I have 3 comments' });
+      let comments = yield Comment.create([
+        { content: 'Cool first post' },
+        { content: 'Very cool first post' },
+        { content: 'Super cool first post' }
+      ]);
+
+      post1.commentsIds = comments;
+      yield post1.save();
+
+      const post2 = new Post({ title: 'I have 4 comments' });
+      comments = yield Comment.create([
+        { content: 'Cool second post' },
+        { content: 'Very cool second post' },
+        { content: 'Super cool second post' },
+        { content: 'Absolutely cool second post' }
+      ]);
+      post2.commentsIds = comments;
+      yield post2.save();
+
+      const posts = yield Post.find().populate({ path: 'commentsIds', select: 'content -_id', perDocumentLimit: 2 });
+  
+      assert.equal(posts[0].commentsIds.length, 2);
+      assert.equal(posts[1].commentsIds.length, 2);
+    });
+  });
 });

From 1a843e39612599b3d26c5accbd60a107a620512e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 10:29:30 -0400
Subject: [PATCH 1012/2348] fix(populate): handle deselected foreign field with
 `perDocumentLimit` and multiple documents

Fix #9175
---
 .../populate/removeDeselectedForeignField.js  | 31 +++++++++++++++++++
 lib/model.js                                  | 21 ++++---------
 2 files changed, 37 insertions(+), 15 deletions(-)
 create mode 100644 lib/helpers/populate/removeDeselectedForeignField.js

diff --git a/lib/helpers/populate/removeDeselectedForeignField.js b/lib/helpers/populate/removeDeselectedForeignField.js
new file mode 100644
index 00000000000..57cc01774e8
--- /dev/null
+++ b/lib/helpers/populate/removeDeselectedForeignField.js
@@ -0,0 +1,31 @@
+'use strict';
+
+const get = require('../get');
+const mpath = require('mpath');
+const parseProjection = require('../projection/parseProjection');
+
+/*!
+ * ignore
+ */
+
+module.exports = function removeDeselectedForeignField(foreignFields, options, docs) {
+  const projection = parseProjection(get(options, 'select', null), true) ||
+    parseProjection(get(options, 'options.select', null), true);
+
+  if (projection == null) {
+    return;
+  }
+  for (const foreignField of foreignFields) {
+    if (!projection.hasOwnProperty('-' + foreignField)) {
+      continue;
+    }
+
+    for (const val of docs) {
+      if (val.$__ != null) {
+        mpath.unset(foreignField, val._doc);
+      } else {
+        mpath.unset(foreignField, val);
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index d82239de298..34af9f5a98b 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -34,6 +34,7 @@ const castBulkWrite = require('./helpers/model/castBulkWrite');
 const getDefaultBulkwriteResult = require('./helpers/getDefaultBulkwriteResult');
 const discriminator = require('./helpers/model/discriminator');
 const each = require('./helpers/each');
+const get = require('./helpers/get');
 const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const getModelsMapForPopulate = require('./helpers/populate/getModelsMapForPopulate');
 const immediate = require('./helpers/immediate');
@@ -41,13 +42,11 @@ const internalToObjectOptions = require('./options').internalToObjectOptions;
 const isDefaultIdIndex = require('./helpers/indexes/isDefaultIdIndex');
 const isIndexEqual = require('./helpers/indexes/isIndexEqual');
 const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedInclusive');
-const get = require('./helpers/get');
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
 const modifiedPaths = require('./helpers/update/modifiedPaths');
-const mpath = require('mpath');
 const parallelLimit = require('./helpers/parallelLimit');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
-const parseProjection = require('./helpers/projection/parseProjection');
+const removeDeselectedForeignField = require('./helpers/populate/removeDeselectedForeignField');
 const util = require('util');
 const utils = require('./utils');
 
@@ -4465,6 +4464,10 @@ function populate(model, docs, options, callback) {
       const assignmentOpts = arr[3];
       _assign(model, vals, mod, assignmentOpts);
     }
+
+    for (const arr of params) {
+      removeDeselectedForeignField(arr[0].foreignField, arr[0].options, vals);
+    }
     callback();
   }
 }
@@ -4531,8 +4534,6 @@ function _assign(model, vals, mod, assignmentOpts) {
   const justOne = mod.justOne;
   let _val;
   const lean = get(options, 'options.lean', false);
-  const projection = parseProjection(get(options, 'select', null), true) ||
-    parseProjection(get(options, 'options.select', null), true);
   const len = vals.length;
   const rawOrder = {};
   const rawDocs = {};
@@ -4602,16 +4603,6 @@ function _assign(model, vals, mod, assignmentOpts) {
       } else {
         val.$__.wasPopulated = true;
       }
-
-      // gh-8460: if user used `-foreignField`, assume this means they
-      // want the foreign field unset even if it isn't excluded in the query.
-      if (projection != null && projection.hasOwnProperty('-' + foreignField)) {
-        if (val.$__ != null) {
-          val.set(foreignField, void 0);
-        } else {
-          mpath.unset(foreignField, val);
-        }
-      }
     }
   }
 

From f46e56b430889314e268c199c715cf0f32fef220 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 10:34:49 -0400
Subject: [PATCH 1013/2348] style: fix lint

---
 lib/helpers/populate/removeDeselectedForeignField.js | 2 +-
 test/model.populate.test.js                          | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/populate/removeDeselectedForeignField.js b/lib/helpers/populate/removeDeselectedForeignField.js
index 57cc01774e8..39b893a9d14 100644
--- a/lib/helpers/populate/removeDeselectedForeignField.js
+++ b/lib/helpers/populate/removeDeselectedForeignField.js
@@ -28,4 +28,4 @@ module.exports = function removeDeselectedForeignField(foreignFields, options, d
       }
     }
   }
-}
\ No newline at end of file
+};
\ No newline at end of file
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 2b1cbd68bf4..3aeef5025a0 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9483,7 +9483,7 @@ describe('model: populate:', function() {
       commentsIds: [{ type: Schema.ObjectId, ref: 'Comment' }]
     });
     const Post = db.model('Post', postSchema);
-  
+
     const commentSchema = new Schema({ content: String });
     const Comment = db.model('Comment', commentSchema);
 
@@ -9509,7 +9509,7 @@ describe('model: populate:', function() {
       yield post2.save();
 
       const posts = yield Post.find().populate({ path: 'commentsIds', select: 'content -_id', perDocumentLimit: 2 });
-  
+
       assert.equal(posts[0].commentsIds.length, 2);
       assert.equal(posts[1].commentsIds.length, 2);
     });

From 11371a68629ab708c93f1dcc079bd8a1716b7c10 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 11:37:45 -0400
Subject: [PATCH 1014/2348] test(populate): repro #9153

---
 test/model.populate.test.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 3aeef5025a0..97422eb4dfa 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9514,4 +9514,36 @@ describe('model: populate:', function() {
       assert.equal(posts[1].commentsIds.length, 2);
     });
   });
+
+  it('handles embedded discriminator `refPath` with multiple documents (gh-8731) (gh-9153)', function() {
+    const nested = Schema({}, { discriminatorKey: 'type' });
+    const mySchema = Schema({ title: { type: String }, items: [nested] });
+
+    const itemType = mySchema.path('items');
+
+    itemType.discriminator('link', Schema({
+      fooType: { type: String },
+      foo: {
+        type: mongoose.Schema.Types.ObjectId,
+        refPath: 'items.fooType'
+      }
+    }));
+
+    const Model = db.model('Test', mySchema);
+
+    return co(function*() {
+      const doc1 = yield Model.create({ title: 'doc1' });
+      const doc2 = yield Model.create({
+        title: 'doc2',
+        items: [{
+          type: 'link',
+          fooType: 'Test',
+          foo: doc1._id
+        }]
+      });
+
+      const docs = yield Model.find({ }).sort({ title: 1 }).populate('items.foo').exec();
+      assert.equal(docs[1].items[0].foo.title, 'doc1');
+    });
+  });
 });

From c0d56e6192651b22723cc59540cce3150b23b604 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 11:38:15 -0400
Subject: [PATCH 1015/2348] fix(populate): handle embedded discriminator
 `refPath` with multiple documents

Fix #9153
---
 lib/helpers/populate/getModelsMapForPopulate.js | 5 +++--
 test/model.populate.test.js                     | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 3c81d46d2ae..438eeee78d0 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -232,7 +232,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     if (isRefPath && normalizedRefPath != null) {
       const pieces = normalizedRefPath.split('.');
       let cur = '';
-      for (const piece of pieces) {
+      for (let j = 0; j < pieces.length; ++j) {
+        const piece = pieces[j];
         cur = cur + (cur.length === 0 ? '' : '.') + piece;
         const schematype = modelSchema.path(cur);
         if (schematype != null &&
@@ -256,7 +257,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
               ret = ret.map(v => v === docValue ? SkipPopulateValue(v) : v);
               continue;
             }
-            const modelName = utils.getValue(pieces.slice(i + 1).join('.'), subdoc);
+            const modelName = utils.getValue(pieces.slice(j + 1).join('.'), subdoc);
             modelNames.push(modelName);
           }
         }
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 97422eb4dfa..eaf15e3df71 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9533,7 +9533,7 @@ describe('model: populate:', function() {
 
     return co(function*() {
       const doc1 = yield Model.create({ title: 'doc1' });
-      const doc2 = yield Model.create({
+      yield Model.create({
         title: 'doc2',
         items: [{
           type: 'link',

From eeb9c9e320116851c7e176efbb009e3caad80e1d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 17:28:24 -0400
Subject: [PATCH 1016/2348] feat(query): add overwriteDiscriminatorKey option
 that allows changing the discriminator key in `findOneAndUpdate()`,
 `updateOne()`, etc.

Fix #6087
---
 lib/query.js              | 21 +++++++++++++++++++--
 test/model.update.test.js | 29 +++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index dbdd0f2ce8a..fec883f175c 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1293,7 +1293,8 @@ Query.prototype.getOptions = function() {
  * - [writeConcern](https://docs.mongodb.com/manual/reference/method/db.collection.update/)
  * - [timestamps](https://mongoosejs.com/docs/guide.html#timestamps): If `timestamps` is set in the schema, set this option to `false` to skip timestamps for that particular update. Has no effect if `timestamps` is not enabled in the schema options.
  * - omitUndefined: delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
- *
+ * - overwriteDiscriminatorKey: allow setting the discriminator key in the update. Will use the correct discriminator schema if the update changes the discriminator key.
+ * 
  * The following options are only for `find()`, `findOne()`, `findById()`, `findOneAndUpdate()`, and `findByIdAndUpdate()`:
  *
  * - [lean](./api.html#query_Query-lean)
@@ -1361,6 +1362,10 @@ Query.prototype.setOptions = function(options, overwrite) {
     this._mongooseOptions.setDefaultsOnInsert = options.setDefaultsOnInsert;
     delete options.setDefaultsOnInsert;
   }
+  if ('overwriteDiscriminatorKey' in options) {
+    this._mongooseOptions.overwriteDiscriminatorKey = options.overwriteDiscriminatorKey;
+    delete options.overwriteDiscriminatorKey;
+  }
 
   return Query.base.setOptions.call(this, options);
 };
@@ -4485,6 +4490,19 @@ Query.prototype._post = function(fn) {
 
 Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
   let strict;
+  let schema = this.schema;
+
+  const discriminatorKey = schema.options.discriminatorKey;
+  const baseSchema = schema._baseSchema ? schema._baseSchema : schema;
+  if (this._mongooseOptions.overwriteDiscriminatorKey &&
+      obj[discriminatorKey] != null &&
+      baseSchema.discriminators) {
+    const _schema = baseSchema.discriminators[obj[discriminatorKey]];
+    if (_schema != null) {
+      schema = _schema;
+    }
+  }
+
   if ('strict' in this._mongooseOptions) {
     strict = this._mongooseOptions.strict;
   } else if (this.schema && this.schema.options) {
@@ -4508,7 +4526,6 @@ Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
     upsert = this.options.upsert;
   }
 
-  let schema = this.schema;
   const filter = this._conditions;
   if (schema != null &&
       utils.hasUserDefinedProperty(filter, schema.options.discriminatorKey) &&
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 8e8c517d865..a465a379287 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3478,4 +3478,33 @@ describe('model: updateOne: ', function() {
       });
     });
   });
+
+  describe('overwriteDiscriminatorKey', function() {
+    it('allows changing discriminator key in update (gh-6087)', function() {
+      const baseSchema = new Schema({}, { discriminatorKey: 'type' });
+      const baseModel = db.model('Test', baseSchema);
+
+      const aSchema = Schema({ aThing: Number }, { _id: false, id: false });
+      const aModel = baseModel.discriminator('A', aSchema);
+
+      const bSchema = new Schema({ bThing: String }, { _id: false, id: false });
+      const bModel = baseModel.discriminator('B', bSchema);
+
+      return co(function*() {
+        // Model is created as a type A
+        let doc = yield baseModel.create({ type: 'A', aThing: 1 });
+
+        yield aModel.updateOne(
+          { _id: doc._id },
+          { type: 'B', bThing: 'two' },
+          { runValidators: true, overwriteDiscriminatorKey: true }
+        );
+
+        doc = yield baseModel.findById(doc);
+        assert.equal(doc.type, 'B');
+        assert.ok(doc instanceof bModel);
+        assert.equal(doc.bThing, 'two');
+      });
+    });
+  });
 });
\ No newline at end of file

From 655114b9a80923eb4f7941f426a9b408567684d6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 30 Jun 2020 17:50:01 -0400
Subject: [PATCH 1017/2348] style: fix lint

---
 lib/query.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/query.js b/lib/query.js
index fec883f175c..3cc41c64562 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1294,7 +1294,7 @@ Query.prototype.getOptions = function() {
  * - [timestamps](https://mongoosejs.com/docs/guide.html#timestamps): If `timestamps` is set in the schema, set this option to `false` to skip timestamps for that particular update. Has no effect if `timestamps` is not enabled in the schema options.
  * - omitUndefined: delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * - overwriteDiscriminatorKey: allow setting the discriminator key in the update. Will use the correct discriminator schema if the update changes the discriminator key.
- * 
+ *
  * The following options are only for `find()`, `findOne()`, `findById()`, `findOneAndUpdate()`, and `findByIdAndUpdate()`:
  *
  * - [lean](./api.html#query_Query-lean)

From 9761ced8160397889a992dc0052c93ff6f8560d3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jul 2020 10:30:08 -0400
Subject: [PATCH 1018/2348] chore: quick copy change

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index b3c41c10c3d..a8614bbb749 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3437,7 +3437,7 @@ function applySchemaTypeTransforms(self, json) {
 
 function throwErrorIfPromise(path, transformedValue) {
   if (isPromise(transformedValue)) {
-    throw new Error('`transform` option has to be synchronous, but is returning a promise on path `' + path + '`.');
+    throw new Error('`transform` function must be synchronous, but the transform on path `' + path + '` returned a promise.');
   }
 }
 

From 74be8fc913c5da26cf216fb50965f769a1ce403c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jul 2020 10:41:59 -0400
Subject: [PATCH 1019/2348] docs: add target="_blank" to all edit links

Fix #9058
---
 docs/acquit.pug              | 2 +-
 docs/api.pug                 | 2 +-
 docs/api_split.pug           | 2 +-
 docs/async-await.pug         | 2 +-
 docs/browser.pug             | 2 +-
 docs/built-with-mongoose.pug | 2 +-
 docs/compatibility.pug       | 2 +-
 docs/connections.pug         | 2 +-
 docs/deprecations.pug        | 2 +-
 docs/documents.pug           | 2 +-
 docs/faq.pug                 | 2 +-
 docs/further_reading.pug     | 2 +-
 docs/geojson.pug             | 2 +-
 docs/guide.pug               | 2 +-
 docs/guides.pug              | 2 +-
 docs/jest.pug                | 2 +-
 docs/lambda.pug              | 2 +-
 docs/middleware.pug          | 2 +-
 docs/migration.pug           | 2 +-
 docs/models.pug              | 2 +-
 docs/plugins.pug             | 2 +-
 docs/populate.pug            | 2 +-
 docs/queries.pug             | 2 +-
 docs/schematypes.pug         | 2 +-
 docs/subdocs.pug             | 2 +-
 docs/transactions.pug        | 2 +-
 website.js                   | 2 +-
 27 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/docs/acquit.pug b/docs/acquit.pug
index 6997a9aade9..5f035da7859 100644
--- a/docs/acquit.pug
+++ b/docs/acquit.pug
@@ -1,7 +1,7 @@
 extends layout
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/api.pug b/docs/api.pug
index 56c300cda1b..196e2806b84 100644
--- a/docs/api.pug
+++ b/docs/api.pug
@@ -30,7 +30,7 @@ block content
   each item in docs
     hr.separate-api
     div.item-header-wrap
-      <a class="edit-docs-link" href="#{item.editLink}">
+      <a class="edit-docs-link" href="#{item.editLink}" target="_blank">
         <img src="/docs/images/pencil.svg" />
       </a>
       h2(id=item.name, class="item-header")
diff --git a/docs/api_split.pug b/docs/api_split.pug
index 83f8b6ac074..ada490a6ac5 100644
--- a/docs/api_split.pug
+++ b/docs/api_split.pug
@@ -15,7 +15,7 @@ append style
     }
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
   h1 #{name}
diff --git a/docs/async-await.pug b/docs/async-await.pug
index 1f8a588d3a8..9429e4d8dd9 100644
--- a/docs/async-await.pug
+++ b/docs/async-await.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/browser.pug b/docs/browser.pug
index eedd9217bab..bc15a1b91c8 100644
--- a/docs/browser.pug
+++ b/docs/browser.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
index e6a76d956d5..69d5b13bf25 100644
--- a/docs/built-with-mongoose.pug
+++ b/docs/built-with-mongoose.pug
@@ -1,7 +1,7 @@
 extends layout
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/compatibility.pug b/docs/compatibility.pug
index 085fafb9f70..a6e5b942f86 100644
--- a/docs/compatibility.pug
+++ b/docs/compatibility.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/connections.pug b/docs/connections.pug
index 930ef08fa00..a76fa43dac4 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/deprecations.pug b/docs/deprecations.pug
index 7c0c0dff005..dea93a31b55 100644
--- a/docs/deprecations.pug
+++ b/docs/deprecations.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/documents.pug b/docs/documents.pug
index 1a7c89c058e..12526491939 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/faq.pug b/docs/faq.pug
index b36fce37bf6..49f0090171b 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -17,7 +17,7 @@ block append style
     }
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/further_reading.pug b/docs/further_reading.pug
index 3fff2b60490..17165a16761 100644
--- a/docs/further_reading.pug
+++ b/docs/further_reading.pug
@@ -21,7 +21,7 @@ append style
     }
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/geojson.pug b/docs/geojson.pug
index 2236b081a21..0873c3f41e0 100644
--- a/docs/geojson.pug
+++ b/docs/geojson.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/guide.pug b/docs/guide.pug
index f80b4770314..f6e37a84c07 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/guides.pug b/docs/guides.pug
index f77256a4277..20c220c949f 100644
--- a/docs/guides.pug
+++ b/docs/guides.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/jest.pug b/docs/jest.pug
index 16c5682b3c3..ca70187c2ce 100644
--- a/docs/jest.pug
+++ b/docs/jest.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/lambda.pug b/docs/lambda.pug
index 29123a9f96b..1b5b952058a 100644
--- a/docs/lambda.pug
+++ b/docs/lambda.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/middleware.pug b/docs/middleware.pug
index d0eaead34c7..3c09f637828 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/migration.pug b/docs/migration.pug
index eaca733d94e..e60b227e808 100644
--- a/docs/migration.pug
+++ b/docs/migration.pug
@@ -7,7 +7,7 @@ block append style
     }
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/models.pug b/docs/models.pug
index b47da9b52b5..a97d379ce63 100644
--- a/docs/models.pug
+++ b/docs/models.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/plugins.pug b/docs/plugins.pug
index 17b4149865b..8ccbd317528 100644
--- a/docs/plugins.pug
+++ b/docs/plugins.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/populate.pug b/docs/populate.pug
index 3eecdd5d6cd..a2a5cdf0497 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/queries.pug b/docs/queries.pug
index 05a813c85d6..85f94f4b56b 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index fc40f23da01..a7115336b37 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index 50b4c31b051..86a5bb9de88 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -5,7 +5,7 @@ append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/docs/transactions.pug b/docs/transactions.pug
index b6762f439a0..0aab8125ec8 100644
--- a/docs/transactions.pug
+++ b/docs/transactions.pug
@@ -5,7 +5,7 @@ block append style
   script(type="text/javascript" src="/docs/js/native.js")
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
 
diff --git a/website.js b/website.js
index 617859f924e..23010b7bff2 100644
--- a/website.js
+++ b/website.js
@@ -76,7 +76,7 @@ append style
     p { line-height: 1.5em }
 
 block content
-  <a class="edit-docs-link" href="#{editLink}">
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
     <img src="/docs/images/pencil.svg" />
   </a>
   :markdown

From 0e4ee447c3ca78e716c9425c3ad70593cf34f938 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jul 2020 10:47:31 -0400
Subject: [PATCH 1020/2348] test: fix tests

---
 test/document.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 9ef1d2d3e00..9066bd60190 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8991,13 +8991,13 @@ describe('document', function() {
     const user = new User({ name: 'Hafez' });
     assert.throws(function() {
       user.toJSON();
-    }, /`transform` option has to be synchronous, but is returning a promise on path `name`./);
+    }, /must be synchronous/);
 
     assert.throws(function() {
       user.toObject();
-    }, /`transform` option has to be synchronous, but is returning a promise on path `name`./);
+    }, /must be synchronous/);
   });
-    
+
   it('uses strict equality when checking mixed paths for modifications (gh-9165)', function() {
     const schema = Schema({ obj: {} });
     const Model = db.model('gh9165', schema);

From 4b1ecdc5f5477975c8eb0b257aaeba92ec9fa50e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jul 2020 12:30:01 -0400
Subject: [PATCH 1021/2348] chore: update opencollective sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index 0f79603fb2f..ac945e00a72 100644
--- a/index.pug
+++ b/index.pug
@@ -262,9 +262,6 @@ html(lang='en')
               <a href="https://www.bonus.com.de/freispiele">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-deutschland/646169e/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.monetta.pl/">
-                <img class="sponsor" src="https://images.opencollective.com/monetta/7d65ae6/logo.png" style="height: 100px">
-              </a>
               <a href="https://www.minitool.com/">
                 <img class="sponsor" src="https://images.opencollective.com/minitool-solution-ltd/1519aa6/logo.png" style="height: 100px">
               </a>
@@ -277,9 +274,6 @@ html(lang='en')
               <a href="https://searchpromocodes.com/">
                 <img class="sponsor" src="https://images.opencollective.com/searchpromocodes/68ae5dd/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://unscramblex.com/">
-                <img class="sponsor" src="https://images.opencollective.com/unscramblex/87d6a68/logo/256.png" style="height: 100px">
-              </a>
               <a href="https://www.nettikasinot.org/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-org/bbd887f/logo/256.png" style="height: 100px">
               </a>

From 0d60630a983e7f0b96128986d9724e3e3e24a421 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jul 2020 18:01:43 -0400
Subject: [PATCH 1022/2348] chore: release 5.9.21

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 46818236721..dda130fe3f8 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.9.21 / 2020-07-01
+===================
+ * fix: propagate `typeKey` option to implicitly created schemas from `typePojoToMixed` #9185 [joaoritter](https://github.com/joaoritter)
+ * fix(populate): handle embedded discriminator `refPath` with multiple documents #9153
+ * fix(populate): handle deselected foreign field with `perDocumentLimit` and multiple documents #9175
+ * fix(document): disallow `transform` functions that return promises #9176 #9163 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(document): use strict equality when checking mixed paths for modifications #9165
+ * docs: add target="_blank" to all edit links #9058
+
 5.9.20 / 2020-06-22
 ===================
  * fix(populate): handle populating primitive array under document array discriminator #9148
diff --git a/package.json b/package.json
index d40aadaaadd..ac0becb777e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.20",
+  "version": "5.9.21",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 156de0c850ecc916b7d4e3ef3dc1844ee566cabf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 1 Jul 2020 19:07:51 -0400
Subject: [PATCH 1023/2348] feat(connection): add `getClient()` and
 `setClient()` function for interacting with a connection's underlying
 MongoClient instance

Fix #9164
---
 lib/connection.js       | 285 ++++++++++++++++++++++++----------------
 test/connection.test.js |  17 +++
 2 files changed, 187 insertions(+), 115 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index d8e60bd6e00..31c35af3ee4 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -753,18 +753,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
     });
   });
 
-  const _handleReconnect = () => {
-    // If we aren't disconnected, we assume this reconnect is due to a
-    // socket timeout. If there's no activity on a socket for
-    // `socketTimeoutMS`, the driver will attempt to reconnect and emit
-    // this event.
-    if (_this.readyState !== STATES.connected) {
-      _this.readyState = STATES.connected;
-      _this.emit('reconnect');
-      _this.emit('reconnected');
-    }
-  };
-
   const promise = new Promise((resolve, reject) => {
     if (_this.client != null) {
       _this.client.close();
@@ -778,111 +766,9 @@ Connection.prototype.openUri = function(uri, options, callback) {
         return reject(error);
       }
 
-      const db = dbName != null ? client.db(dbName) : client.db();
-      _this.db = db;
-
-      // `useUnifiedTopology` events
-      const type = get(db, 's.topology.s.description.type', '');
-      if (options.useUnifiedTopology) {
-        if (type === 'Single') {
-          const server = Array.from(db.s.topology.s.servers.values())[0];
-
-          server.s.topology.on('serverHeartbeatSucceeded', () => {
-            _handleReconnect();
-          });
-          server.s.pool.on('reconnect', () => {
-            _handleReconnect();
-          });
-          client.on('serverDescriptionChanged', ev => {
-            const newDescription = ev.newDescription;
-            if (newDescription.type === 'Standalone') {
-              _handleReconnect();
-            } else {
-              _this.readyState = STATES.disconnected;
-            }
-          });
-        } else if (type.startsWith('ReplicaSet')) {
-          client.on('topologyDescriptionChanged', ev => {
-            // Emit disconnected if we've lost connectivity to _all_ servers
-            // in the replica set.
-            const description = ev.newDescription;
-            const servers = Array.from(ev.newDescription.servers.values());
-            const allServersDisconnected = description.type === 'ReplicaSetNoPrimary' &&
-              servers.reduce((cur, d) => cur || d.type === 'Unknown', false);
-            if (_this.readyState === STATES.connected && allServersDisconnected) {
-              // Implicitly emits 'disconnected'
-              _this.readyState = STATES.disconnected;
-            } else if (_this.readyState === STATES.disconnected && !allServersDisconnected) {
-              _handleReconnect();
-            }
-          });
-
-          db.on('close', function() {
-            const type = get(db, 's.topology.s.description.type', '');
-            if (type !== 'ReplicaSetWithPrimary') {
-              // Implicitly emits 'disconnected'
-              _this.readyState = STATES.disconnected;
-            }
-          });
-        }
-      }
-
-      // Backwards compat for mongoose 4.x
-      db.on('reconnect', function() {
-        _handleReconnect();
-      });
-      db.s.topology.on('reconnectFailed', function() {
-        _this.emit('reconnectFailed');
-      });
-
-      if (!options.useUnifiedTopology) {
-        db.s.topology.on('left', function(data) {
-          _this.emit('left', data);
-        });
-      }
-      db.s.topology.on('joined', function(data) {
-        _this.emit('joined', data);
-      });
-      db.s.topology.on('fullsetup', function(data) {
-        _this.emit('fullsetup', data);
-      });
-      if (get(db, 's.topology.s.coreTopology.s.pool') != null) {
-        db.s.topology.s.coreTopology.s.pool.on('attemptReconnect', function() {
-          _this.emit('attemptReconnect');
-        });
-      }
-      if (!options.useUnifiedTopology || !type.startsWith('ReplicaSet')) {
-        db.on('close', function() {
-          // Implicitly emits 'disconnected'
-          _this.readyState = STATES.disconnected;
-        });
-      }
-
-      if (!options.useUnifiedTopology) {
-        client.on('left', function() {
-          if (_this.readyState === STATES.connected &&
-              get(db, 's.topology.s.coreTopology.s.replicaSetState.topologyType') === 'ReplicaSetNoPrimary') {
-            _this.readyState = STATES.disconnected;
-          }
-        });
-      }
-
-      db.on('timeout', function() {
-        _this.emit('timeout');
-      });
-
-      delete _this.then;
-      delete _this.catch;
-      _this.readyState = STATES.connected;
-
-      for (const i in _this.collections) {
-        if (utils.object.hasOwnProperty(_this.collections, i)) {
-          _this.collections[i].onOpen();
-        }
-      }
+      _setClient(_this, client, options, dbName);
 
       resolve(_this);
-      _this.emit('open');
     });
   });
 
@@ -916,6 +802,125 @@ Connection.prototype.openUri = function(uri, options, callback) {
   return this;
 };
 
+function _setClient(conn, client, options, dbName) {
+  const db = dbName != null ? client.db(dbName) : client.db();
+  conn.db = db;
+  conn.client = client;
+
+  const _handleReconnect = () => {
+    // If we aren't disconnected, we assume this reconnect is due to a
+    // socket timeout. If there's no activity on a socket for
+    // `socketTimeoutMS`, the driver will attempt to reconnect and emit
+    // this event.
+    if (conn.readyState !== STATES.connected) {
+      conn.readyState = STATES.connected;
+      conn.emit('reconnect');
+      conn.emit('reconnected');
+    }
+  };
+
+  // `useUnifiedTopology` events
+  const type = get(db, 's.topology.s.description.type', '');
+  if (options.useUnifiedTopology) {
+    if (type === 'Single') {
+      const server = Array.from(db.s.topology.s.servers.values())[0];
+      server.s.topology.on('serverHeartbeatSucceeded', () => {
+        _handleReconnect();
+      });
+      server.s.pool.on('reconnect', () => {
+        _handleReconnect();
+      });
+      client.on('serverDescriptionChanged', ev => {
+        const newDescription = ev.newDescription;
+        if (newDescription.type === 'Standalone') {
+          _handleReconnect();
+        } else {
+          conn.readyState = STATES.disconnected;
+        }
+      });
+    } else if (type.startsWith('ReplicaSet')) {
+      client.on('topologyDescriptionChanged', ev => {
+        // Emit disconnected if we've lost connectivity to _all_ servers
+        // in the replica set.
+        const description = ev.newDescription;
+        const servers = Array.from(ev.newDescription.servers.values());
+        const allServersDisconnected = description.type === 'ReplicaSetNoPrimary' &&
+          servers.reduce((cur, d) => cur || d.type === 'Unknown', false);
+        if (conn.readyState === STATES.connected && allServersDisconnected) {
+          // Implicitly emits 'disconnected'
+          conn.readyState = STATES.disconnected;
+        } else if (conn.readyState === STATES.disconnected && !allServersDisconnected) {
+          _handleReconnect();
+        }
+      });
+
+      db.on('close', function() {
+        const type = get(db, 's.topology.s.description.type', '');
+        if (type !== 'ReplicaSetWithPrimary') {
+          // Implicitly emits 'disconnected'
+          conn.readyState = STATES.disconnected;
+        }
+      });
+    }
+  }
+
+  // Backwards compat for mongoose 4.x
+  db.on('reconnect', function() {
+    _handleReconnect();
+  });
+  db.s.topology.on('reconnectFailed', function() {
+    conn.emit('reconnectFailed');
+  });
+
+  if (!options.useUnifiedTopology) {
+    db.s.topology.on('left', function(data) {
+      conn.emit('left', data);
+    });
+  }
+  db.s.topology.on('joined', function(data) {
+    conn.emit('joined', data);
+  });
+  db.s.topology.on('fullsetup', function(data) {
+    conn.emit('fullsetup', data);
+  });
+  if (get(db, 's.topology.s.coreTopology.s.pool') != null) {
+    db.s.topology.s.coreTopology.s.pool.on('attemptReconnect', function() {
+      conn.emit('attemptReconnect');
+    });
+  }
+  if (!options.useUnifiedTopology || !type.startsWith('ReplicaSet')) {
+    db.on('close', function() {
+      // Implicitly emits 'disconnected'
+      conn.readyState = STATES.disconnected;
+    });
+  }
+
+  if (!options.useUnifiedTopology) {
+    client.on('left', function() {
+      if (conn.readyState === STATES.connected &&
+          get(db, 's.topology.s.coreTopology.s.replicaSetState.topologyType') === 'ReplicaSetNoPrimary') {
+        conn.readyState = STATES.disconnected;
+      }
+    });
+  }
+
+  db.on('timeout', function() {
+    conn.emit('timeout');
+  });
+
+  delete conn.then;
+  delete conn.catch;
+  conn.readyState = STATES.connected;
+
+  for (const i in conn.collections) {
+    if (utils.object.hasOwnProperty(conn.collections, i)) {
+      conn.collections[i].onOpen();
+    }
+  }
+
+  conn.emit('open');
+}
+
 /*!
  * ignore
  */
@@ -1330,6 +1335,56 @@ Connection.prototype.optionsProvideAuthenticationData = function(options) {
       ((options.pass) || this.authMechanismDoesNotRequirePassword());
 };
 
+/**
+ * Returns the [MongoDB driver `MongoClient`](http://mongodb.github.io/node-mongodb-native/3.5/api/MongoClient.html) instance
+ * that this connection uses to talk to MongoDB.
+ *
+ * ####Example:
+ *     const conn = await mongoose.createConnection('mongodb://localhost:27017/test');
+ *
+ *     conn.getClient(); // MongoClient { ... }
+ *
+ * @api public
+ * @return {MongoClient}
+ */
+
+Connection.prototype.getClient = function getClient() {
+  return this.client;
+};
+
+/**
+ * Set the [MongoDB driver `MongoClient`](http://mongodb.github.io/node-mongodb-native/3.5/api/MongoClient.html) instance
+ * that this connection uses to talk to MongoDB. This is useful if you already have a MongoClient instance, and want to
+ * reuse it.
+ *
+ * ####Example:
+ *     const client = await mongodb.MongoClient.connect('mongodb://localhost:27017/test');
+ *
+ *     const conn = mongoose.createConnection().setClient(client);
+ *
+ *     conn.getClient(); // MongoClient { ... }
+ *     conn.readyState; // 1, means 'CONNECTED'
+ *
+ * @api public
+ * @return {Connection} this
+ */
+
+Connection.prototype.setClient = function setClient(client) {
+  if (!(client instanceof mongodb.MongoClient)) {
+    throw new MongooseError('Must call `setClient()` with an instance of MongoClient');
+  }
+  if (this.client != null || this.readyState !== STATES.disconnected) {
+    throw new MongooseError('Cannot call `setClient()` on a connection that is already connected.');
+  }
+  if (!client.isConnected()) {
+    throw new MongooseError('Cannot call `setClient()` with a MongoClient that is not connected.');
+  }
+
+  _setClient(this, client, { useUnifiedTopology: client.s.options.useUnifiedTopology }, client.s.options.dbName);
+
+  return this;
+};
+
 /**
  * Switches to a different database using the same connection pool.
  *
diff --git a/test/connection.test.js b/test/connection.test.js
index f259e6d590f..e0a81a31ee1 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -10,6 +10,7 @@ const Promise = require('bluebird');
 const Q = require('q');
 const assert = require('assert');
 const co = require('co');
+const mongodb = require('mongodb');
 const server = require('./common').server;
 
 const mongoose = start.mongoose;
@@ -1185,4 +1186,20 @@ describe('connections:', function() {
       assert.equal(db2.config.useCreateIndex, true);
     });
   });
+
+  it('allows setting client on a disconnected connection (gh-9164)', function() {
+    return co(function*() {
+      const client = yield mongodb.MongoClient.connect('mongodb://localhost:27017/mongoose_test', {
+        useNewUrlParser: true,
+        useUnifiedTopology: true
+      });
+      const conn = mongoose.createConnection().setClient(client);
+
+      assert.equal(conn.readyState, 1);
+
+      yield conn.createCollection('test');
+      const res = yield conn.dropCollection('test');
+      assert.ok(res);
+    });
+  });
 });

From 1bca5d10931c4508555120ccbf6ee2f6adfc39f8 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 04:37:51 +0200
Subject: [PATCH 1024/2348] docs(model): fix typo

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 63eb74c3a15..8e46b28ca25 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2784,7 +2784,7 @@ Model.findByIdAndDelete = function(id, options, callback) {
  * @param {Object} filter Replace the first document that matches this filter
  * @param {Object} [replacement] Replace with this document
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Boolean} [options.new=false] By default, `findOneAndReplace()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndReplace()` will instead give you the object after `update` was applied.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)

From 2398073c2ae3d130ea19f0d8539b759ecc60fd8d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 05:01:21 +0200
Subject: [PATCH 1025/2348] test: repro #9183

---
 test/model.test.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 9d674f158c5..55504f3ad3a 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6839,4 +6839,36 @@ describe('Model', function() {
       );
     });
   });
+
+  describe('defaultNewOnFindAndUpdate', function() {
+    const originalValue = mongoose.get('defaultNewOnFindAndUpdate');
+    beforeEach(() => {
+      mongoose.set('defaultNewOnFindAndUpdate', true);
+    });
+
+    afterEach(() => {
+      mongoose.set('defaultNewOnFindAndUpdate', originalValue);
+    });
+
+    it('Setting `defaultNewOnFindAndUpdate` works (gh-9183)', function() {
+      return co(function*() {
+        const userSchema = new Schema({
+          name: { type: String }
+        });
+
+        const User = db.model('User', userSchema);
+
+        const createdUser = yield User.create({ name: 'Hafez' });
+
+        const user1 = yield User.findOneAndUpdate({ _id: createdUser._id }, { name: 'Hafez1' });
+        assert.equal(user1.name, 'Hafez1');
+
+        const user2 = yield User.findByIdAndUpdate(createdUser._id, { name: 'Hafez2' });
+        assert.equal(user2.name, 'Hafez2');
+
+        const user3 = yield User.findOneAndReplace({ _id: createdUser._id }, { name: 'Hafez3' });
+        assert.equal(user3.name, 'Hafez3');
+      });
+    });
+  });
 });

From d3bfee429d84107bcfcd83c24677f6b267b8f517 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 05:07:13 +0200
Subject: [PATCH 1026/2348] feat(base): add option to set
 defaultNewOnFindAndUpdate

---
 lib/query.js        | 33 +++++++++++++++++++++------------
 lib/validoptions.js |  5 +++--
 2 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 3cc41c64562..4c36c2d0c2b 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3004,20 +3004,23 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
     this._mergeUpdate(doc);
   }
 
-  if (options) {
-    options = utils.clone(options);
-    if (options.projection) {
-      this.select(options.projection);
-      delete options.projection;
-    }
-    if (options.fields) {
-      this.select(options.fields);
-      delete options.fields;
-    }
+  options = options ? utils.clone(options) : {};
 
-    this.setOptions(options);
+  if (options.projection) {
+    this.select(options.projection);
+    delete options.projection;
+  }
+  if (options.fields) {
+    this.select(options.fields);
+    delete options.fields;
+  }
+
+  if (Object.prototype.hasOwnProperty.call(options, 'new') === false) {
+    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdate');
   }
 
+  this.setOptions(options);
+
   if (!callback) {
     return this;
   }
@@ -3335,7 +3338,13 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
     this._mergeUpdate(replacement);
   }
 
-  options && this.setOptions(options);
+  options = options || {};
+
+  if (Object.prototype.hasOwnProperty.call(options, 'new') === false) {
+    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdate');
+  }
+
+  this.setOptions(options);
 
   if (!callback) {
     return this;
diff --git a/lib/validoptions.js b/lib/validoptions.js
index a9c8a352d23..39c037f2e79 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -12,6 +12,7 @@ const VALID_OPTIONS = Object.freeze([
   'bufferCommands',
   'cloneSchemas',
   'debug',
+  'defaultNewOnFindAndUpdate',
   'maxTimeMS',
   'objectIdGetter',
   'runValidators',
@@ -21,12 +22,12 @@ const VALID_OPTIONS = Object.freeze([
   'strictQuery',
   'toJSON',
   'toObject',
+  'typePojoToMixed',
   'useCreateIndex',
   'useFindAndModify',
   'useNewUrlParser',
   'usePushEach',
-  'useUnifiedTopology',
-  'typePojoToMixed'
+  'useUnifiedTopology'
 ]);
 
 module.exports = VALID_OPTIONS;

From 92610fc55c6e894dc2d44d3d05184933c29e06db Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 05:14:05 +0200
Subject: [PATCH 1027/2348] docs(base): add defaultNewOnFindAndUpdateOrReplace
 as a valid option this also changes option name defaultNewOnFindAndUpdate ->
 defaultNewOnFindAndUpdateOrReplace

---
 lib/index.js        |  1 +
 lib/query.js        |  4 ++--
 lib/validoptions.js |  2 +-
 test/model.test.js  | 10 +++++-----
 4 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index a72fdddffc6..02cab261e52 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -147,6 +147,7 @@ Mongoose.prototype.driver = require('./driver');
  *
  * Currently supported options are:
  * - 'debug': If `true`, prints the operations mongoose sends to MongoDB to the console. If a writable stream is passed, it will log to that stream, without colorization. If a callback function is passed, it will receive the collection name, the method name, then all arugments passed to the method. For example, if you wanted to replicate the default logging, you could output from the callback `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
+ * - 'defaultNewOnFindAndUpdateOrReplace': If `true`, changes the default `new` option to `findOneAndUpdate()`, `findByIdAndUpdate` and `findOneAndReplace()` to true.
  * - 'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models
  * - 'useCreateIndex': false by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
  * - 'useFindAndModify': true by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
diff --git a/lib/query.js b/lib/query.js
index 4c36c2d0c2b..1bf11fa6265 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3016,7 +3016,7 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
   }
 
   if (Object.prototype.hasOwnProperty.call(options, 'new') === false) {
-    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdate');
+    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
   }
 
   this.setOptions(options);
@@ -3341,7 +3341,7 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
   options = options || {};
 
   if (Object.prototype.hasOwnProperty.call(options, 'new') === false) {
-    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdate');
+    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
   }
 
   this.setOptions(options);
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 39c037f2e79..7b092b2fefb 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -12,7 +12,7 @@ const VALID_OPTIONS = Object.freeze([
   'bufferCommands',
   'cloneSchemas',
   'debug',
-  'defaultNewOnFindAndUpdate',
+  'defaultNewOnFindAndUpdateOrReplace',
   'maxTimeMS',
   'objectIdGetter',
   'runValidators',
diff --git a/test/model.test.js b/test/model.test.js
index 96263769807..1b0fb28e503 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6869,17 +6869,17 @@ describe('Model', function() {
     });
   });
 
-  describe('defaultNewOnFindAndUpdate', function() {
-    const originalValue = mongoose.get('defaultNewOnFindAndUpdate');
+  describe('defaultNewOnFindAndUpdateOrReplace', function() {
+    const originalValue = mongoose.get('defaultNewOnFindAndUpdateOrReplace');
     beforeEach(() => {
-      mongoose.set('defaultNewOnFindAndUpdate', true);
+      mongoose.set('defaultNewOnFindAndUpdateOrReplace', true);
     });
 
     afterEach(() => {
-      mongoose.set('defaultNewOnFindAndUpdate', originalValue);
+      mongoose.set('defaultNewOnFindAndUpdateOrReplace', originalValue);
     });
 
-    it('Setting `defaultNewOnFindAndUpdate` works (gh-9183)', function() {
+    it('Setting `defaultNewOnFindAndUpdateOrReplace` works (gh-9183)', function() {
       return co(function*() {
         const userSchema = new Schema({
           name: { type: String }

From 263f1c47e67a6154f64afe3bd52e6c13fb47d621 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 05:26:19 +0200
Subject: [PATCH 1028/2348] fix(query): set default option only if it's not
 null

---
 lib/query.js | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 1bf11fa6265..09bc76a549f 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3015,8 +3015,10 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
     delete options.fields;
   }
 
-  if (Object.prototype.hasOwnProperty.call(options, 'new') === false) {
-    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
+
+  const defaultNew = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
+  if (defaultNew != null && Object.prototype.hasOwnProperty.call(options, 'new') === false) {
+    options.new = defaultNew;
   }
 
   this.setOptions(options);
@@ -3340,8 +3342,9 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
 
   options = options || {};
 
-  if (Object.prototype.hasOwnProperty.call(options, 'new') === false) {
-    options.new = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
+  const defaultNew = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
+  if (defaultNew != null && Object.prototype.hasOwnProperty.call(options, 'new') === false) {
+    options.new = defaultNew;
   }
 
   this.setOptions(options);

From 7613aed85dc40a1abb0708e84d7afd8101e01dda Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 05:31:11 +0200
Subject: [PATCH 1029/2348] treat `new` undefined as not mentioned on
 findOneAndUpdate

---
 lib/query.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 09bc76a549f..447b9aab9d2 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3017,7 +3017,7 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
 
 
   const defaultNew = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
-  if (defaultNew != null && Object.prototype.hasOwnProperty.call(options, 'new') === false) {
+  if (defaultNew != null && options.new == null) {
     options.new = defaultNew;
   }
 
@@ -3343,7 +3343,7 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
   options = options || {};
 
   const defaultNew = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
-  if (defaultNew != null && Object.prototype.hasOwnProperty.call(options, 'new') === false) {
+  if (defaultNew != null && options.new == null) {
     options.new = defaultNew;
   }
 

From 86f0c8413807f7484a8347de51eadc6a30e3fb98 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 2 Jul 2020 06:07:09 +0200
Subject: [PATCH 1030/2348] test(model): add test case verifying
 defaultNewOnFindAndUpdateOrReplace can be overwritten

---
 test/model.test.js | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 1b0fb28e503..a10d69346c4 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6869,7 +6869,7 @@ describe('Model', function() {
     });
   });
 
-  describe('defaultNewOnFindAndUpdateOrReplace', function() {
+  describe('defaultNewOnFindAndUpdateOrReplace (gh-9183)', function() {
     const originalValue = mongoose.get('defaultNewOnFindAndUpdateOrReplace');
     beforeEach(() => {
       mongoose.set('defaultNewOnFindAndUpdateOrReplace', true);
@@ -6879,7 +6879,7 @@ describe('Model', function() {
       mongoose.set('defaultNewOnFindAndUpdateOrReplace', originalValue);
     });
 
-    it('Setting `defaultNewOnFindAndUpdateOrReplace` works (gh-9183)', function() {
+    it('Setting `defaultNewOnFindAndUpdateOrReplace` works', function() {
       return co(function*() {
         const userSchema = new Schema({
           name: { type: String }
@@ -6899,5 +6899,26 @@ describe('Model', function() {
         assert.equal(user3.name, 'Hafez3');
       });
     });
+
+    it('`defaultNewOnFindAndUpdateOrReplace` can be overwritten', function() {
+      return co(function*() {
+        const userSchema = new Schema({
+          name: { type: String }
+        });
+
+        const User = db.model('User', userSchema);
+
+        const createdUser = yield User.create({ name: 'Hafez' });
+
+        const user1 = yield User.findOneAndUpdate({ _id: createdUser._id }, { name: 'Hafez1' }, { new: false });
+        assert.equal(user1.name, 'Hafez');
+
+        const user2 = yield User.findByIdAndUpdate(createdUser._id, { name: 'Hafez2' }, { new: false });
+        assert.equal(user2.name, 'Hafez1');
+
+        const user3 = yield User.findOneAndReplace({ _id: createdUser._id }, { name: 'Hafez3' }, { new: false });
+        assert.equal(user3.name, 'Hafez2');
+      });
+    });
   });
 });

From 0edb94dfdbb484b8557e3651305867e38bfd8c4c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jul 2020 16:54:31 -0400
Subject: [PATCH 1031/2348] feat(connection): make transaction() helper reset
 array atomics after failed transaction

Fix #8380
---
 lib/connection.js               | 14 +++++++
 lib/plugins/trackTransaction.js | 66 ++++++++++++++++++++++++++++++++-
 test/docs/transactions.test.js  | 29 ++++++++++++---
 3 files changed, 102 insertions(+), 7 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 31c35af3ee4..6e34ff12bbf 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -22,6 +22,7 @@ const utils = require('./utils');
 
 const parseConnectionString = require('mongodb/lib/core').parseConnectionString;
 
+const arrayAtomicsSymbol = require('./helpers/symbols').arrayAtomicsSymbol;
 const sessionNewDocuments = require('./helpers/symbols').sessionNewDocuments;
 
 let id = 0;
@@ -469,6 +470,19 @@ Connection.prototype.transaction = function transaction(fn) {
           if (state.hasOwnProperty('versionKey')) {
             doc.set(doc.schema.options.versionKey, state.versionKey);
           }
+
+          for (const path of state.modifiedPaths) {
+            doc.$__.activePaths.paths[path] = 'modify';
+            doc.$__.activePaths.states.modify[path] = true;
+          }
+
+          for (const path of state.atomics.keys()) {
+            const val = doc.$__getValue(path);
+            if (val == null) {
+              continue;
+            }
+            val[arrayAtomicsSymbol] = state.atomics.get(path);
+          }
         }
         delete session[sessionNewDocuments];
         throw err;
diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index 52d9d231f67..4a7ddc45c5d 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -1,5 +1,6 @@
 'use strict';
 
+const arrayAtomicsSymbol = require('../helpers/symbols').arrayAtomicsSymbol;
 const sessionNewDocuments = require('../helpers/symbols').sessionNewDocuments;
 
 module.exports = function trackTransaction(schema) {
@@ -21,7 +22,70 @@ module.exports = function trackTransaction(schema) {
         initialState.versionKey = this.get(this.schema.options.versionKey);
       }
 
+      initialState.modifiedPaths = new Set(Object.keys(this.$__.activePaths.states.modify));
+      initialState.atomics = _getAtomics(this);
+
       session[sessionNewDocuments].set(this, initialState);
+    } else {
+      const state = session[sessionNewDocuments].get(this);
+
+      for (const path of Object.keys(this.$__.activePaths.states.modify)) {
+        state.modifiedPaths.add(path);
+      }
+      state.atomics = _getAtomics(this, state.atomics);
     }
   });
-};
\ No newline at end of file
+};
+
+function _getAtomics(doc, previous) {
+  const pathToAtomics = new Map();
+  previous = previous || new Map();
+
+  const pathsToCheck = Object.keys(doc.$__.activePaths.init).concat(Object.keys(doc.$__.activePaths.modify));
+
+  for (const path of pathsToCheck) {
+    const val = doc.$__getValue(path);
+    if (val != null &&
+        val instanceof Array &&
+        val.isMongooseDocumentArray &&
+        val.length &&
+        val[arrayAtomicsSymbol] != null &&
+        Object.keys(val[arrayAtomicsSymbol]).length > 0) {
+      const existing = previous.get(path) || {};
+      pathToAtomics.set(path, mergeAtomics(existing, val[arrayAtomicsSymbol]));
+    }
+  }
+
+  const dirty = doc.$__dirty();
+  for (const dirt of dirty) {
+    const path = dirt.path;
+
+    const val = dirt.value;
+    if (val != null && val[arrayAtomicsSymbol] != null && Object.keys(val[arrayAtomicsSymbol]).length > 0) {
+      const existing = previous.get(path) || {};
+      pathToAtomics.set(path, mergeAtomics(existing, val[arrayAtomicsSymbol]));
+    }
+  }
+
+  return pathToAtomics;
+}
+
+function mergeAtomics(destination, source) {
+  destination = destination || {};
+
+  if (source.$pullAll != null) {
+    destination.$pullAll = (destination.$pullAll || []).concat(source.$pullAll);
+  }
+  if (source.$push != null) {
+    destination.$push = destination.$push || {};
+    destination.$push.$each = (destination.$push.$each || []).concat(source.$push.$each);
+  }
+  if (source.$addToSet != null) {
+    destination.$addToSet = (destination.$addToSet || []).concat(source.$addToSet);
+  }
+  if (source.$set != null) {
+    destination.$set = Object.assign(destination.$set, source.$set);
+  }
+
+  return destination;
+}
\ No newline at end of file
diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
index 8d66c775fc3..429f4fb5e5f 100644
--- a/test/docs/transactions.test.js
+++ b/test/docs/transactions.test.js
@@ -386,22 +386,39 @@ describe('transactions', function() {
 
   it('can save document after aborted transaction (gh-8380)', function() {
     return co(function*() {
-      const schema = Schema({ name: String, arr: [String] });
+      const schema = Schema({ name: String, arr: [String], arr2: [String] });
 
       const Test = db.model('gh8380', schema);
 
       yield Test.createCollection();
-      yield Test.create({ name: 'foo', arr: ['bar'] });
+      yield Test.create({ name: 'foo', arr: ['bar'], arr2: ['foo'] });
       const doc = yield Test.findOne();
       yield db.
         transaction(session => co(function*() {
-          doc.arr.pop();
+          doc.arr.pull('bar');
+          doc.arr2.push('bar');
+
           yield doc.save({ session });
+
+          doc.name = 'baz';
           throw new Error('Oops');
         })).
-        catch(err => assert.equal(err.message, 'Oops'));
-      doc.set('arr.0', 'qux');
-      yield doc.save();
+        catch(err => {
+          assert.equal(err.message, 'Oops');
+        });
+
+      const changes = doc.$__delta()[1];
+      assert.equal(changes.$set.name, 'baz');
+      assert.deepEqual(changes.$pullAll.arr, ['bar']);
+      assert.deepEqual(changes.$push.arr2, { $each: ['bar'] });
+      assert.ok(!changes.$set.arr2);
+
+      yield doc.save({ session: null });
+
+      const newDoc = yield Test.collection.findOne();
+      assert.equal(newDoc.name, 'baz');
+      assert.deepEqual(newDoc.arr, []);
+      assert.deepEqual(newDoc.arr2, ['foo', 'bar']);
     });
   });
 });

From 78e2854bf1624d925df2b824c6a0a80ebecde1f7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Jul 2020 17:59:57 -0400
Subject: [PATCH 1032/2348] feat: start work on upgrading to mongodb driver 3.6

---
 lib/model.js               |  4 ++--
 package.json               | 34 +++++++++++++++++++++++-----------
 test/model.indexes.test.js | 22 ++++++++++++----------
 3 files changed, 37 insertions(+), 23 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 34af9f5a98b..741c645bd88 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1357,7 +1357,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
     cb = this.$wrapCallback(cb);
 
     this.createCollection(err => {
-      if (err) {
+      if (err != null && err.codeName !== 'NamespaceExists') {
         return cb(err);
       }
       this.cleanIndexes((err, dropped) => {
@@ -4898,7 +4898,7 @@ Model.$wrapCallback = function(callback) {
     if (err != null && err.name === 'MongoServerSelectionError') {
       arguments[0] = serverSelectionError.assimilateError(err);
     }
-    if (err != null && err.name === 'MongoNetworkError' && err.message.endsWith('timed out')) {
+    if (err != null && err.name === 'MongoNetworkTimeoutError' && err.message.endsWith('timed out')) {
       _this.db.emit('timeout');
     }
 
diff --git a/package.json b/package.json
index ac0becb777e..1f4bebeb3b5 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.5.9",
+    "mongodb": "git@github.com:mongodb/node-mongodb-native.git#3.6",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",
@@ -134,13 +134,22 @@
       "no-const-assign": "error",
       "no-useless-rename": "error",
       "no-dupe-keys": "error",
-      "space-in-parens": ["error", "never"],
-      "spaced-comment": ["error", "always", {
-        "block": {
-          "markers": ["!"],
-          "balanced": true
+      "space-in-parens": [
+        "error",
+        "never"
+      ],
+      "spaced-comment": [
+        "error",
+        "always",
+        {
+          "block": {
+            "markers": [
+              "!"
+            ],
+            "balanced": true
+          }
         }
-      }],
+      ],
       "key-spacing": [
         "error",
         {
@@ -156,10 +165,13 @@
         }
       ],
       "array-bracket-spacing": 1,
-      "arrow-spacing": ["error", {
-        "before": true,
-        "after": true
-      }],
+      "arrow-spacing": [
+        "error",
+        {
+          "before": true,
+          "after": true
+        }
+      ],
       "object-curly-spacing": [
         "error",
         "always"
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 43547aff57e..2c7a60059a4 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -20,7 +20,7 @@ describe('model', function() {
   before(function() {
     db = start();
 
-    return db.createCollection('Test');
+    return db.createCollection('Test').catch(() => {});
   });
 
   after(function(done) {
@@ -458,16 +458,18 @@ describe('model', function() {
     const schema = new Schema({ arr: [childSchema] });
     const Model = db.model('Test', schema);
 
-    return Model.init().
-      then(() => Model.syncIndexes()).
-      then(() => Model.listIndexes()).
-      then(indexes => {
-        assert.equal(indexes.length, 2);
-        assert.ok(indexes[1].partialFilterExpression);
-        assert.deepEqual(indexes[1].partialFilterExpression, {
-          'arr.name': { $exists: true }
-        });
+    return co(function*() {
+      yield Model.init();
+
+      yield Model.syncIndexes();
+      const indexes = yield Model.listIndexes();
+
+      assert.equal(indexes.length, 2);
+      assert.ok(indexes[1].partialFilterExpression);
+      assert.deepEqual(indexes[1].partialFilterExpression, {
+        'arr.name': { $exists: true }
       });
+    });
   });
 
   it('skips automatic indexing on childSchema if autoIndex: false (gh-9150)', function() {

From fd42b589d0bb68e3abd7280cf16808ca8dd9da7a Mon Sep 17 00:00:00 2001
From: EarthFeng <samtsai15@gmail.com>
Date: Fri, 3 Jul 2020 20:14:16 +0800
Subject: [PATCH 1033/2348] Update guide.pug

Aliases h5 > h3
---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index f6e37a84c07..c4f501f4cdd 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -364,7 +364,7 @@ block content
     Only non-virtual properties work as part of queries and for field selection.
     Since virtuals are not stored in MongoDB, you can't query with them.
 
-    <h5 id="aliases"><a href="#aliases">Aliases</a></h5>
+    <h3 id="aliases"><a href="#aliases">Aliases</a></h3>
 
     Aliases are a particular type of virtual where the getter and setter
     seamlessly get and set another property. This is handy for saving network

From f3be50732ba1bf4fd82780878efe18af896c7586 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jul 2020 11:03:06 -0400
Subject: [PATCH 1034/2348] test(update): repro #9172

---
 test/model.update.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 8e8c517d865..6b5e7f83b4b 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3478,4 +3478,22 @@ describe('model: updateOne: ', function() {
       });
     });
   });
+
+  it('update validators respect storeSubdocValidationError (gh-9172)', function() {
+    const opts = { storeSubdocValidationError: false };
+    const Model = db.model('Test', Schema({
+      nested: Schema({
+        arr: [{ name: { type: String, required: true } }]
+      }, opts)
+    }));
+
+    return co(function*() {
+      const opts = { runValidators: true };
+      const err = yield Model.updateOne({}, { nested: { arr: [{}] } }, opts).catch(err => err);
+
+      assert.ok(err);
+      assert.ok(err.errors['nested.arr.0.name']);
+      assert.ok(!err.errors['nested']);
+    });
+  });
 });
\ No newline at end of file

From 86e2791157450cb18cd5a1fb0d7c0f26b0513a9f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jul 2020 11:06:05 -0400
Subject: [PATCH 1035/2348] fix(update): respect storeSubdocValidationError
 option with update validators

Fix #9172
---
 lib/helpers/updateValidators.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/helpers/updateValidators.js b/lib/helpers/updateValidators.js
index b6ecaacf84c..aeea6344539 100644
--- a/lib/helpers/updateValidators.js
+++ b/lib/helpers/updateValidators.js
@@ -155,7 +155,14 @@ module.exports = function(query, schema, castedDoc, options, callback) {
               return callback(null);
             }
           }
+
           schemaPath.doValidate(v, function(err) {
+            if (schemaPath.schema != null &&
+                schemaPath.schema.options.storeSubdocValidationError === false &&
+                err instanceof ValidationError) {
+              return callback(null);
+            }
+
             if (err) {
               err.path = updates[i];
               validationErrors.push(err);

From 6fea8c34dac56cbaa10557f77a474ec22d218df2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jul 2020 11:33:50 -0400
Subject: [PATCH 1036/2348] docs: add a note about SSL validation to migration
 guide

Re: #9147
---
 docs/migrating_to_5.pug | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/docs/migrating_to_5.pug b/docs/migrating_to_5.pug
index 01471324a00..f2f46790ded 100644
--- a/docs/migrating_to_5.pug
+++ b/docs/migrating_to_5.pug
@@ -60,6 +60,7 @@ block content
     * [debug output defaults to stdout instead of stderr](#debug-output)
     * [Overwriting filter properties](#overwrite-filter)
     * [`bulkWrite()` results](#bulkwrite-results)
+    * [Strict SSL validation](#strict-ssl-validation)
 
     <h3 id="version-requirements"><a href="#version-requirements">Version Requirements</a></h3>
 
@@ -555,4 +556,17 @@ block content
       upsertedIds: {},
       insertedIds: { '0': 5be9a1c87decfc6443dd9f18 },
       n: 1 }
+    ```
+
+    <h3 id="strict-ssl-validation"><a href="#strict-ssl-validation">
+      Strict SSL Validation
+    </a></h3>
+
+    The most recent versions of the [MongoDB Node.js driver use strict SSL validation by default](http://mongodb.github.io/node-mongodb-native/3.5/tutorials/connect/tls/),
+    which may lead to errors if you're using [self-signed certificates](https://github.com/Automattic/mongoose/issues/9147).
+
+    If this is blocking you from upgrading, you can set the `tlsInsecure` option to `true`.
+
+    ```javascript
+    mongoose.connect(uri, { tlsInsecure: false }); // Opt out of additional SSL validation
     ```
\ No newline at end of file

From ab3b38c15edf92563ced9cb64160402a5d6d4389 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 3 Jul 2020 19:10:37 +0200
Subject: [PATCH 1037/2348] rename `defaultNewOnFindAndUpdateOrReplace` to
 `returnOriginal`

---
 lib/index.js        |  2 +-
 lib/query.js        | 12 ++++++------
 lib/validoptions.js |  2 +-
 test/model.test.js  | 12 ++++++------
 4 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 02cab261e52..324f5af9d63 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -147,7 +147,7 @@ Mongoose.prototype.driver = require('./driver');
  *
  * Currently supported options are:
  * - 'debug': If `true`, prints the operations mongoose sends to MongoDB to the console. If a writable stream is passed, it will log to that stream, without colorization. If a callback function is passed, it will receive the collection name, the method name, then all arugments passed to the method. For example, if you wanted to replicate the default logging, you could output from the callback `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
- * - 'defaultNewOnFindAndUpdateOrReplace': If `true`, changes the default `new` option to `findOneAndUpdate()`, `findByIdAndUpdate` and `findOneAndReplace()` to true.
+ * - 'returnOriginal': If `false`, changes the default `new` option to `findOneAndUpdate()`, `findByIdAndUpdate` and `findOneAndReplace()` to true.
  * - 'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models
  * - 'useCreateIndex': false by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
  * - 'useFindAndModify': true by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
diff --git a/lib/query.js b/lib/query.js
index 447b9aab9d2..eb81328612e 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3016,9 +3016,9 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
   }
 
 
-  const defaultNew = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
-  if (defaultNew != null && options.new == null) {
-    options.new = defaultNew;
+  const returnOriginal = get(this, 'model.base.options.returnOriginal');
+  if (options.new == null && returnOriginal != null) {
+    options.new = !returnOriginal;
   }
 
   this.setOptions(options);
@@ -3342,9 +3342,9 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
 
   options = options || {};
 
-  const defaultNew = get(this, 'model.base.options.defaultNewOnFindAndUpdateOrReplace');
-  if (defaultNew != null && options.new == null) {
-    options.new = defaultNew;
+  const returnOriginal = get(this, 'model.base.options.returnOriginal');
+  if (options.new == null && returnOriginal != null) {
+    options.new = !returnOriginal;
   }
 
   this.setOptions(options);
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 7b092b2fefb..6e50ec6b69d 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -12,9 +12,9 @@ const VALID_OPTIONS = Object.freeze([
   'bufferCommands',
   'cloneSchemas',
   'debug',
-  'defaultNewOnFindAndUpdateOrReplace',
   'maxTimeMS',
   'objectIdGetter',
+  'returnOriginal',
   'runValidators',
   'selectPopulatedPaths',
   'setDefaultsOnInsert',
diff --git a/test/model.test.js b/test/model.test.js
index a10d69346c4..6fcfb2ca6f2 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6869,17 +6869,17 @@ describe('Model', function() {
     });
   });
 
-  describe('defaultNewOnFindAndUpdateOrReplace (gh-9183)', function() {
-    const originalValue = mongoose.get('defaultNewOnFindAndUpdateOrReplace');
+  describe('returnOriginal (gh-9183)', function() {
+    const originalValue = mongoose.get('returnOriginal');
     beforeEach(() => {
-      mongoose.set('defaultNewOnFindAndUpdateOrReplace', true);
+      mongoose.set('returnOriginal', false);
     });
 
     afterEach(() => {
-      mongoose.set('defaultNewOnFindAndUpdateOrReplace', originalValue);
+      mongoose.set('returnOriginal', originalValue);
     });
 
-    it('Setting `defaultNewOnFindAndUpdateOrReplace` works', function() {
+    it('Setting `returnOriginal` works', function() {
       return co(function*() {
         const userSchema = new Schema({
           name: { type: String }
@@ -6900,7 +6900,7 @@ describe('Model', function() {
       });
     });
 
-    it('`defaultNewOnFindAndUpdateOrReplace` can be overwritten', function() {
+    it('`returnOriginal` can be overwritten', function() {
       return co(function*() {
         const userSchema = new Schema({
           name: { type: String }

From 90b3217f8d2dea718f50e55b53c6c556692b0f11 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 3 Jul 2020 19:18:11 +0200
Subject: [PATCH 1038/2348] docs(model): add note to use global option
 `returnOriginal`

---
 lib/model.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index cb7c472468f..d5845136d7f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2445,7 +2445,7 @@ Model.$where = function $where() {
  * @param {Object} [conditions]
  * @param {Object} [update]
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Boolean} [options.new=false] By default, `findOneAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied. To change the default to `true`, use `mongoose.set('returnOriginal', false);`.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
@@ -2588,7 +2588,7 @@ function _decorateUpdateWithVersionKey(update, options, versionKey) {
  * @param {Object|Number|String} id value of `_id` to query by
  * @param {Object} [update]
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Boolean} [options.new=false] By default, `findByIdAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied.
+ * @param {Boolean} [options.new=false] By default, `findByIdAndUpdate()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndUpdate()` will instead give you the object after `update` was applied. To change the default to `true`, use `mongoose.set('returnOriginal', false);`.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
@@ -2787,7 +2787,7 @@ Model.findByIdAndDelete = function(id, options, callback) {
  * @param {Object} filter Replace the first document that matches this filter
  * @param {Object} [replacement] Replace with this document
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
- * @param {Boolean} [options.new=false] By default, `findOneAndReplace()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndReplace()` will instead give you the object after `update` was applied.
+ * @param {Boolean} [options.new=false] By default, `findOneAndReplace()` returns the document as it was **before** `update` was applied. If you set `new: true`, `findOneAndReplace()` will instead give you the object after `update` was applied. To change the default to `true`, use `mongoose.set('returnOriginal', false);`.
  * @param {Object} [options.lean] if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See [`Query.lean()`](/docs/api.html#query_Query-lean) and [the Mongoose lean tutorial](/docs/tutorials/lean.html).
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)

From 53fa7880fb5f773edfa344a348f63ece84f043a6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Jul 2020 13:25:57 -0400
Subject: [PATCH 1039/2348] feat(document): add `useProjection` option to
 `toObject()` and `toJSON()` for hiding deselected fields on newly created
 documents

Fix #9118
---
 lib/document.js       | 38 ++++++++++++++++++++++++++++++++++++++
 test/document.test.js | 12 ++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index da884c9e509..d52dddc5409 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -30,6 +30,7 @@ const isExclusive = require('./helpers/projection/isExclusive');
 const inspect = require('util').inspect;
 const internalToObjectOptions = require('./options').internalToObjectOptions;
 const mpath = require('mpath');
+const queryhelpers = require('./queryhelpers');
 const utils = require('./utils');
 const isPromise = require('./helpers/isPromise');
 
@@ -3084,6 +3085,10 @@ Document.prototype.$toObject = function(options, json) {
     applySchemaTypeTransforms(this, ret);
   }
 
+  if (options.useProjection) {
+    omitDeselectedFields(this, ret);
+  }
+
   if (transform === true || (schemaOptions.toObject && transform)) {
     const opts = options.json ? schemaOptions.toJSON : schemaOptions.toObject;
 
@@ -3119,6 +3124,7 @@ Document.prototype.$toObject = function(options, json) {
  * - `depopulate` depopulate any populated paths, replacing them with their original refs, defaults to false
  * - `versionKey` whether to include the version key, defaults to true
  * - `flattenMaps` convert Maps to POJOs. Useful if you want to JSON.stringify() the result of toObject(), defaults to false
+ * - `useProjection` set to `true` to omit fields that are excluded in this document's projection. Unless you specified a projection, this will omit any field that has `select: false` in the schema.
  *
  * ####Getters/Virtuals
  *
@@ -3243,6 +3249,7 @@ Document.prototype.$toObject = function(options, json) {
  * @param {Boolean} [options.depopulate=false] if true, replace any conventionally populated paths with the original id in the output. Has no affect on virtual populated paths.
  * @param {Boolean} [options.versionKey=true] if false, exclude the version key (`__v` by default) from the output
  * @param {Boolean} [options.flattenMaps=false] if true, convert Maps to POJOs. Useful if you want to `JSON.stringify()` the result of `toObject()`.
+ * @param {Boolean} [options.useProjection=false] - If true, omits fields that are excluded in this document's projection. Unless you specified a projection, this will omit any field that has `select: false` in the schema.
  * @return {Object} js object
  * @see mongodb.Binary http://mongodb.github.com/node-mongodb-native/api-bson-generated/binary.html
  * @api public
@@ -3446,6 +3453,37 @@ function throwErrorIfPromise(path, transformedValue) {
   }
 }
 
+/*!
+ * ignore
+ */
+
+function omitDeselectedFields(self, json) {
+  const schema = self.schema;
+  const paths = Object.keys(schema.paths || {});
+  const cur = self._doc;
+
+  if (!cur) {
+    return json;
+  }
+
+  let selected = self.$__.selected;
+  if (selected === void 0) {
+    selected = {};
+    queryhelpers.applyPaths(selected, schema);
+  }
+  if (selected == null || Object.keys(selected).length === 0) {
+    return json;
+  }
+
+  for (const path of paths) {
+    if (selected[path] != null && !selected[path]) {
+      delete json[path];
+    }
+  }
+
+  return json;
+}
+
 /**
  * The return value of this method is used in calls to JSON.stringify(doc).
  *
diff --git a/test/document.test.js b/test/document.test.js
index 7c714f9cf9a..7d9b19b0c3c 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9057,4 +9057,16 @@ describe('document', function() {
       then(doc => Model.findById(doc)).
       then(doc => assert.strictEqual(doc.obj.key, 2));
   });
+
+  it('supports `useProjection` option for `toObject()` (gh-9118)', function() {
+    const authorSchema = new mongoose.Schema({
+      name: String,
+      hiddenField: { type: String, select: false }
+    });
+
+    const Author = db.model('Author', authorSchema);
+
+    const example = new Author({ name: 'John', hiddenField: 'A secret' });
+    assert.strictEqual(example.toJSON({ useProjection: true }).hiddenField, void 0);
+  });
 });

From 378f59bb9c388004e07202bdebc2a1ee66a0dd7a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Jul 2020 11:56:48 -0400
Subject: [PATCH 1040/2348] test(schema): repro #9194

---
 test/schema.test.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index ca96a7f5f2d..94f04335c83 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2434,4 +2434,12 @@ describe('schema', function() {
 
     assert.ok(customerSchema.nested['card']);
   });
+
+  it('allows using `mongoose.Schema.Types.Array` as type (gh-9194)', function() {
+    const schema = new Schema({
+      arr: mongoose.Schema.Types.Array
+    });
+
+    assert.equal(schema.path('arr').caster.instance, 'Mixed');
+  });
 });

From 3390c5383cc4f11235306b1d9b71acd1eb34d4d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Jul 2020 11:57:01 -0400
Subject: [PATCH 1041/2348] fix(schema): treat `{ type:
 mongoose.Schema.Types.Array }` as equivalent to `{ type: Array }`

Fix #9194
---
 lib/schema.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 8c9f6e70009..ba67410f265 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -897,9 +897,9 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
     return new MongooseTypes.Mixed(path, obj);
   }
 
-  if (Array.isArray(type) || Array === type || type === 'array') {
+  if (Array.isArray(type) || type === Array || type === 'array' || type === MongooseTypes.Array) {
     // if it was specified through { type } look for `cast`
-    let cast = (Array === type || type === 'array')
+    let cast = (type === Array || type === 'array')
       ? obj.cast
       : type[0];
 

From 751680e3f1d9751da7a90c72929aeeab30e383b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Jul 2020 12:52:19 -0400
Subject: [PATCH 1042/2348] fix(connection): make calling `mongoose.connect()`
 while already connected a no-op

Fix #9203
---
 lib/connection.js | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 6e34ff12bbf..a9af7c7d12b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -636,9 +636,6 @@ Connection.prototype.onOpen = function() {
  */
 
 Connection.prototype.openUri = function(uri, options, callback) {
-  this.readyState = STATES.connecting;
-  this._closeCalled = false;
-
   if (typeof options === 'function') {
     callback = options;
     options = null;
@@ -663,6 +660,16 @@ Connection.prototype.openUri = function(uri, options, callback) {
       typeof callback + '"');
   }
 
+  if (this.readyState === STATES.connecting || this.readyState === STATES.connected) {
+    if (typeof callback === 'function') {
+      callback(null, this);
+    }
+    return this;
+  }
+
+  this.readyState = STATES.connecting;
+  this._closeCalled = false;
+
   const Promise = PromiseProvider.get();
   const _this = this;
 
@@ -768,10 +775,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
   });
 
   const promise = new Promise((resolve, reject) => {
-    if (_this.client != null) {
-      _this.client.close();
-    }
-
     const client = new mongodb.MongoClient(uri, options);
     _this.client = client;
     client.connect(function(error) {

From 09b59e4f68bf3afe09ed99992cff9eda78ec1087 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 4 Jul 2020 12:56:48 -0400
Subject: [PATCH 1043/2348] fix: revert fix for #9107 to avoid issues when
 calling `connect()` multiple times

Fix #9167
---
 lib/connection.js | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index b7aaf2f7016..c64e192c1f9 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -707,10 +707,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
   };
 
   const promise = new Promise((resolve, reject) => {
-    if (_this.client != null) {
-      _this.client.close();
-    }
-
     const client = new mongodb.MongoClient(uri, options);
     _this.client = client;
     client.connect(function(error) {

From a3f61ad0d3b337f91e48778dd2867a5cdde24414 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Jul 2020 11:37:10 -0400
Subject: [PATCH 1044/2348] refactor: upgrade to safe-buffer 5.2, remove
 workaround for #7102

Fix #9198
---
 lib/types/buffer.js | 11 ++++-------
 package.json        | 34 +++++++++++++++++++++++-----------
 2 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/lib/types/buffer.js b/lib/types/buffer.js
index 5dbe2d49dcb..6fb905b4a16 100644
--- a/lib/types/buffer.js
+++ b/lib/types/buffer.js
@@ -8,9 +8,6 @@ const Binary = require('../driver').get().Binary;
 const utils = require('../utils');
 const Buffer = require('safe-buffer').Buffer;
 
-// Yes this is weird. See https://github.com/feross/safe-buffer/pull/23
-const proto = Buffer.from('').constructor.prototype;
-
 /**
  * Mongoose Buffer constructor.
  *
@@ -109,7 +106,7 @@ MongooseBuffer.mixin = {
    */
 
   write: function() {
-    const written = proto.write.apply(this, arguments);
+    const written = Buffer.prototype.write.apply(this, arguments);
 
     if (written > 0) {
       this._markModified();
@@ -132,7 +129,7 @@ MongooseBuffer.mixin = {
    */
 
   copy: function(target) {
-    const ret = proto.copy.apply(this, arguments);
+    const ret = Buffer.prototype.copy.apply(this, arguments);
 
     if (target && target.isMongooseBuffer) {
       target._markModified();
@@ -156,11 +153,11 @@ MongooseBuffer.mixin = {
     'writeUInt16LE writeUInt16BE writeUInt32LE writeUInt32BE ' +
     'writeInt16LE writeInt16BE writeInt32LE writeInt32BE ' + 'writeFloatLE writeFloatBE writeDoubleLE writeDoubleBE')
 ).split(' ').forEach(function(method) {
-  if (!proto[method]) {
+  if (!Buffer.prototype[method]) {
     return;
   }
   MongooseBuffer.mixin[method] = function() {
-    const ret = proto[method].apply(this, arguments);
+    const ret = Buffer.prototype[method].apply(this, arguments);
     this._markModified();
     return ret;
   };
diff --git a/package.json b/package.json
index ac0becb777e..1897ef32806 100644
--- a/package.json
+++ b/package.json
@@ -27,7 +27,7 @@
     "mquery": "3.2.2",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
-    "safe-buffer": "5.1.2",
+    "safe-buffer": "5.2.1",
     "sliced": "1.0.1",
     "sift": "7.0.1"
   },
@@ -134,13 +134,22 @@
       "no-const-assign": "error",
       "no-useless-rename": "error",
       "no-dupe-keys": "error",
-      "space-in-parens": ["error", "never"],
-      "spaced-comment": ["error", "always", {
-        "block": {
-          "markers": ["!"],
-          "balanced": true
+      "space-in-parens": [
+        "error",
+        "never"
+      ],
+      "spaced-comment": [
+        "error",
+        "always",
+        {
+          "block": {
+            "markers": [
+              "!"
+            ],
+            "balanced": true
+          }
         }
-      }],
+      ],
       "key-spacing": [
         "error",
         {
@@ -156,10 +165,13 @@
         }
       ],
       "array-bracket-spacing": 1,
-      "arrow-spacing": ["error", {
-        "before": true,
-        "after": true
-      }],
+      "arrow-spacing": [
+        "error",
+        {
+          "before": true,
+          "after": true
+        }
+      ],
       "object-curly-spacing": [
         "error",
         "always"

From ae9c686c5635f6669298664e2478c83a62dea127 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Jul 2020 15:10:52 -0400
Subject: [PATCH 1045/2348] fix(connection): throw error when calling
 `openUri()` on a connected or connecting connection with a different URI

Fix #9203
---
 lib/connection.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index a9af7c7d12b..93c86d90501 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -661,12 +661,19 @@ Connection.prototype.openUri = function(uri, options, callback) {
   }
 
   if (this.readyState === STATES.connecting || this.readyState === STATES.connected) {
+    if (this._connectionString !== uri) {
+      throw new MongooseError('Can\'t call `openUri()` on an active connection with ' +
+        'different connection strings. Make sure you aren\'t calling `mongoose.connect()` ' +
+        'multiple times. See: https://mongoosejs.com/docs/connections.html#multiple_connections');
+    }
+
     if (typeof callback === 'function') {
       callback(null, this);
     }
     return this;
   }
 
+  this._connectionString = uri;
   this.readyState = STATES.connecting;
   this._closeCalled = false;
 
@@ -1397,6 +1404,7 @@ Connection.prototype.setClient = function setClient(client) {
     throw new MongooseError('Cannot call `setClient()` with a MongoClient that is not connected.');
   }
 
+  this._connectionString = client.s.url;
   _setClient(this, client, { useUnifiedTopology: client.s.options.useUnifiedTopology }, client.s.options.dbName);
 
   return this;

From 337e3b94ecc56443f17c87b30595c1c22d6c8f6c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Jul 2020 17:11:32 -0400
Subject: [PATCH 1046/2348] feat(document+populate): add `parent()` function
 that allows you to get the parent document for populated docs

Fix #8092
---
 lib/document.js                    | 24 ++++++++++++++++++
 lib/helpers/populate/assignVals.js | 10 ++++++++
 lib/model.js                       |  3 +++
 lib/options/PopulateOptions.js     |  1 +
 test/model.populate.test.js        | 40 ++++++++++++++++++++++++++++++
 test/query.test.js                 | 15 +++++++----
 6 files changed, 88 insertions(+), 5 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d52dddc5409..b34dfa1f01d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -548,6 +548,16 @@ Document.prototype.$__init = function(doc, opts) {
       } else {
         this.populated(item.path, item._docs[id], item);
       }
+
+      if (item._childDocs == null) {
+        continue;
+      }
+      for (const child of item._childDocs) {
+        if (child == null || child.$__ == null) {
+          continue;
+        }
+        child.$__.parent = this;
+      }
     }
   }
 
@@ -3506,6 +3516,20 @@ Document.prototype.toJSON = function(options) {
   return this.$toObject(options, true);
 };
 
+/**
+ * If this document is a subdocument or populated document, returns the document's
+ * parent. Returns `undefined` otherwise.
+ *
+ * @api public
+ * @method parent
+ * @memberOf Document
+ * @instance
+ */
+
+Document.prototype.parent = function() {
+  return this.$__.parent;
+};
+
 /**
  * Helper for console.log
  *
diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index bd93e81afdc..a9e42192ae0 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -84,6 +84,16 @@ module.exports = function assignVals(o) {
       }, new Map());
     }
 
+    if (isDoc && Array.isArray(valueToSet)) {
+      for (const val of valueToSet) {
+        if (val != null && val.$__ != null) {
+          val.$__.parent = docs[i];
+        }
+      }
+    } else if (isDoc && valueToSet != null && valueToSet.$__ != null) {
+      valueToSet.$__.parent = docs[i];
+    }
+
     if (o.isVirtual && isDoc) {
       docs[i].populated(o.path, o.justOne ? originalIds[0] : originalIds, o.allOptions);
       // If virtual populate and doc is already init-ed, need to walk through
diff --git a/lib/model.js b/lib/model.js
index 34af9f5a98b..a11e7021a5e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4462,6 +4462,9 @@ function populate(model, docs, options, callback) {
     for (const arr of params) {
       const mod = arr[0];
       const assignmentOpts = arr[3];
+      for (const val of vals) {
+        mod.options._childDocs.push(val);
+      }
       _assign(model, vals, mod, assignmentOpts);
     }
 
diff --git a/lib/options/PopulateOptions.js b/lib/options/PopulateOptions.js
index b60d45abda6..5b9819460dc 100644
--- a/lib/options/PopulateOptions.js
+++ b/lib/options/PopulateOptions.js
@@ -5,6 +5,7 @@ const clone = require('../helpers/clone');
 class PopulateOptions {
   constructor(obj) {
     this._docs = {};
+    this._childDocs = [];
 
     if (obj == null) {
       return;
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index eaf15e3df71..3761e6d9d6d 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9546,4 +9546,44 @@ describe('model: populate:', function() {
       assert.equal(docs[1].items[0].foo.title, 'doc1');
     });
   });
+
+  it('Sets the populated document\'s parent() (gh-8092)', function() {
+    const schema = new Schema({
+      single: { type: Number, ref: 'Child' },
+      arr: [{ type: Number, ref: 'Child' }],
+      docArr: [{ ref: { type: Number, ref: 'Child' } }]
+    });
+
+    schema.virtual('myVirtual', {
+      ref: 'Child',
+      localField: 'single',
+      foreignField: '_id',
+      justOne: true
+    });
+
+    const Parent = db.model('Parent', schema);
+    const Child = db.model('Child', Schema({ _id: Number, name: String }));
+
+    return co(function*() {
+      yield Child.create({ _id: 1, name: 'test' });
+
+      yield Parent.create({ single: 1, arr: [1], docArr: [{ ref: 1 }] });
+
+      let doc = yield Parent.findOne().populate('single');
+      assert.ok(doc.single.parent() === doc);
+
+      doc = yield Parent.findOne().populate('arr');
+      assert.ok(doc.arr[0].parent() === doc);
+
+      doc = yield Parent.findOne().populate('docArr.ref');
+      assert.ok(doc.docArr[0].ref.parent() === doc);
+
+      doc = yield Parent.findOne().populate('myVirtual');
+      assert.ok(doc.myVirtual.parent() === doc);
+
+      doc = yield Parent.findOne();
+      yield doc.populate('single').execPopulate();
+      assert.ok(doc.single.parent() === doc);
+    });
+  });
 });
diff --git a/test/query.test.js b/test/query.test.js
index 97a3defe70c..77892657370 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -832,7 +832,8 @@ describe('Query', function() {
         select: undefined,
         model: undefined,
         options: undefined,
-        _docs: {}
+        _docs: {},
+        _childDocs: []
       };
       q.populate(o);
       assert.deepEqual(o, q._mongooseOptions.populate['yellow.brick']);
@@ -844,7 +845,8 @@ describe('Query', function() {
       let o = {
         path: 'yellow.brick',
         match: { bricks: { $lt: 1000 } },
-        _docs: {}
+        _docs: {},
+        _childDocs: []
       };
       q.populate(Object.assign({}, o));
       assert.equal(Object.keys(q._mongooseOptions.populate).length, 1);
@@ -853,7 +855,8 @@ describe('Query', function() {
       q.populate('yellow.brick');
       o = {
         path: 'yellow.brick',
-        _docs: {}
+        _docs: {},
+        _childDocs: []
       };
       assert.equal(Object.keys(q._mongooseOptions.populate).length, 1);
       assert.deepEqual(q._mongooseOptions.populate['yellow.brick'], o);
@@ -866,11 +869,13 @@ describe('Query', function() {
       assert.equal(Object.keys(q._mongooseOptions.populate).length, 2);
       assert.deepEqual(q._mongooseOptions.populate['yellow.brick'], {
         path: 'yellow.brick',
-        _docs: {}
+        _docs: {},
+        _childDocs: []
       });
       assert.deepEqual(q._mongooseOptions.populate['dirt'], {
         path: 'dirt',
-        _docs: {}
+        _docs: {},
+        _childDocs: []
       });
       done();
     });

From e4090b18807542b92d2354b08a94199d03b2c9ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 5 Jul 2020 17:15:48 -0400
Subject: [PATCH 1047/2348] test: fix tests

---
 test/query.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/query.test.js b/test/query.test.js
index 77892657370..e7be2f856de 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1604,7 +1604,7 @@ describe('Query', function() {
       q.setOptions({ read: ['s', [{ dc: 'eu' }]] });
 
       assert.equal(q.options.thing, 'cat');
-      assert.deepEqual(q._mongooseOptions.populate.fans, { path: 'fans', _docs: {} });
+      assert.deepEqual(q._mongooseOptions.populate.fans, { path: 'fans', _docs: {}, _childDocs: [] });
       assert.equal(q.options.batchSize, 10);
       assert.equal(q.options.limit, 4);
       assert.equal(q.options.skip, 3);

From fa246e74ad272adf982351d2d801fa9c200dc337 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Jul 2020 17:48:09 -0400
Subject: [PATCH 1048/2348] chore: release 5.9.22

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index dda130fe3f8..dc7267c5107 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.9.22 / 2020-07-06
+===================
+ * fix(schema): treat `{ type: mongoose.Schema.Types.Array }` as equivalent to `{ type: Array }` #9194
+ * fix: revert fix for #9107 to avoid issues when calling `connect()` multiple times #9167
+ * fix(update): respect storeSubdocValidationError option with update validators #9172
+ * fix: upgrade to safe-buffer 5.2 #9198
+ * docs: add a note about SSL validation to migration guide #9147
+ * docs(schemas): fix inconsistent header #9196 [samtsai15](https://github.com/samtsai15)
+
 5.9.21 / 2020-07-01
 ===================
  * fix: propagate `typeKey` option to implicitly created schemas from `typePojoToMixed` #9185 [joaoritter](https://github.com/joaoritter)
diff --git a/package.json b/package.json
index 1897ef32806..ff0175f5e70 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.21",
+  "version": "5.9.22",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a56fe9f71ffab15f9e56c62da8235b17dc476f2e Mon Sep 17 00:00:00 2001
From: JNa0 <florian.monfort@etudiant.univ-rennes1.fr>
Date: Tue, 7 Jul 2020 09:07:14 +0200
Subject: [PATCH 1049/2348] correction of typo

l. 216: mangaging -> managing
---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index c1c8b996407..1b201b110e8 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -213,7 +213,7 @@ Mongoose.prototype.get = Mongoose.prototype.set;
 /**
  * Creates a Connection instance.
  *
- * Each `connection` instance maps to a single database. This method is helpful when mangaging multiple db connections.
+ * Each `connection` instance maps to a single database. This method is helpful when managing multiple db connections.
  *
  *
  * _Options passed take precedence over options included in connection strings._

From 5f1cbf077662d416e9738cdf20a0f8b91bf1cd54 Mon Sep 17 00:00:00 2001
From: Cyril Gandon <cg@doyouno.com>
Date: Wed, 8 Jul 2020 16:54:21 +0200
Subject: [PATCH 1050/2348] fix(array): only cast array to proper depth if it
 contains an non-array value

---
 lib/helpers/arrayDepth.js |  5 +++--
 lib/schema/array.js       |  2 +-
 test/document.test.js     | 16 ++++++++++++++++
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/arrayDepth.js b/lib/helpers/arrayDepth.js
index 0ac39efeb9e..254db4a8cf1 100644
--- a/lib/helpers/arrayDepth.js
+++ b/lib/helpers/arrayDepth.js
@@ -4,10 +4,10 @@ module.exports = arrayDepth;
 
 function arrayDepth(arr) {
   if (!Array.isArray(arr)) {
-    return { min: 0, max: 0 };
+    return { min: 0, max: 0, containsNonArrayItem: true };
   }
   if (arr.length === 0) {
-    return { min: 1, max: 1 };
+    return { min: 1, max: 1, containsNonArrayItem: false };
   }
 
   const res = arrayDepth(arr[0]);
@@ -19,6 +19,7 @@ function arrayDepth(arr) {
     if (_res.max > res.max) {
       res.max = _res.max;
     }
+    res.containsNonArrayItem = res.containsNonArrayItem || _res.containsNonArrayItem;
   }
 
   res.min = res.min + 1;
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 8e7e8cb989d..8323ce4dd8b 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -280,7 +280,7 @@ SchemaArray.prototype._applySetters = function(value, scope, init, priorVal) {
     // No need to wrap empty arrays
     if (value != null && value.length > 0) {
       const valueDepth = arrayDepth(value);
-      if (valueDepth.min === valueDepth.max && valueDepth.max < depth) {
+      if (valueDepth.min === valueDepth.max && valueDepth.max < depth && valueDepth.containsNonArrayItem) {
         for (let i = valueDepth.max; i < depth; ++i) {
           value = [value];
         }
diff --git a/test/document.test.js b/test/document.test.js
index 9066bd60190..42e0db451a6 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8687,6 +8687,22 @@ describe('document', function() {
     assert.deepEqual(obj.lines, [[[3, 4]]]);
   });
 
+  it('doesnt wrap empty nested array with insufficient depth', function() {
+    const weekSchema = mongoose.Schema({
+      days: {
+        type: [[[Number]]],
+        required: true
+      }
+    });
+
+    const Week = db.model('Test', weekSchema);
+    const emptyWeek = new Week();
+
+    emptyWeek.days = [[], [], [], [], [], [], []];
+    const obj = emptyWeek.toObject();
+    assert.deepEqual(obj.days, [[], [], [], [], [], [], []]);
+  });
+
   it('doesnt wipe out nested keys when setting nested key to empty object with minimize (gh-8565)', function() {
     const opts = { autoIndex: false, autoCreate: false };
     const schema1 = Schema({ plaid: { nestedKey: String } }, opts);

From fa9ffac2ed147d14088f1db7e3a736fef3a42543 Mon Sep 17 00:00:00 2001
From: Cyril Gandon <cg@doyouno.com>
Date: Wed, 8 Jul 2020 17:07:17 +0200
Subject: [PATCH 1051/2348] rebooting travis

---
 lib/helpers/arrayDepth.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/helpers/arrayDepth.js b/lib/helpers/arrayDepth.js
index 254db4a8cf1..2c6f2e58629 100644
--- a/lib/helpers/arrayDepth.js
+++ b/lib/helpers/arrayDepth.js
@@ -11,6 +11,7 @@ function arrayDepth(arr) {
   }
 
   const res = arrayDepth(arr[0]);
+
   for (let i = 1; i < arr.length; ++i) {
     const _res = arrayDepth(arr[i]);
     if (_res.min < res.min) {

From 0c7eab161c2746df64786238194f32ccd0aede25 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 8 Jul 2020 11:28:47 -0400
Subject: [PATCH 1052/2348] docs(schematype): document the `transform` option

Fix #9211
---
 docs/schematypes.pug |  7 ++++---
 lib/schematype.js    | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index a7115336b37..daeccc90405 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -238,9 +238,10 @@ block content
     * `set`: function, defines a custom setter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
     * `alias`: string, mongoose >= 4.10.0 only. Defines a [virtual](./guide.html#virtuals) with the given name that gets/sets this path.
     * `immutable`: boolean, defines path as immutable. Mongoose prevents you from changing immutable paths unless the parent document has `isNew: true`.
+    * `transform`: function, Mongoose calls this function when you call [`Document#toJSON()`](/docs/api/document.html#document_Document-toJSON) function, including when you [`JSON.stringify()`](https://thecodebarbarian.com/the-80-20-guide-to-json-stringify-in-javascript) a document.
 
     ```javascript
-    var numberSchema = new Schema({
+    const numberSchema = new Schema({
       integerOnly: {
         type: Number,
         get: v => Math.round(v),
@@ -249,9 +250,9 @@ block content
       }
     });
 
-    var Number = mongoose.model('Number', numberSchema);
+    const Number = mongoose.model('Number', numberSchema);
 
-    var doc = new Number();
+    const doc = new Number();
     doc.integerOnly = 2.001;
     doc.integerOnly; // 2
     doc.i; // 2
diff --git a/lib/schematype.js b/lib/schematype.js
index 9cb62caf37d..3edff125edc 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -442,6 +442,38 @@ SchemaType.prototype.immutable = function(bool) {
   return this;
 };
 
+/**
+ * Defines a custom function for transforming this path when converting a document to JSON.
+ *
+ * Mongoose calls this function with one parameter: the current `value` of the path. Mongoose
+ * then uses the return value in the JSON output.
+ *
+ * ####Example:
+ *
+ *     const schema = new Schema({
+ *       date: { type: Date, transform: v => v.getFullYear() }
+ *     });
+ *     const Model = mongoose.model('Test', schema);
+ *
+ *     await Model.create({ date: new Date('2016-06-01') });
+ *     const doc = await Model.findOne();
+ *
+ *     doc.date instanceof Date; // true
+ *
+ *     doc.toJSON().date; // 2016 as a number
+ *     JSON.stringify(doc); // '{"_id":...,"date":2016}'
+ *
+ * @param {Function} fn
+ * @return {SchemaType} this
+ * @api public
+ */
+
+SchemaType.prototype.transform = function(fn) {
+  this.options.transform = fn;
+
+  return this;
+};
+
 /**
  * Adds a setter to this schematype.
  *

From 6a438c9ae86c82e960014ffb76eb8a33d8324979 Mon Sep 17 00:00:00 2001
From: Calvin Huang <calvin@scaleapi.com>
Date: Thu, 9 Jul 2020 12:22:01 -0700
Subject: [PATCH 1053/2348] don't throw error when comparing options w/wo
 collation

---
 lib/helpers/indexes/isIndexEqual.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/indexes/isIndexEqual.js b/lib/helpers/indexes/isIndexEqual.js
index f3d7e1668c7..bbfe75f0df6 100644
--- a/lib/helpers/indexes/isIndexEqual.js
+++ b/lib/helpers/indexes/isIndexEqual.js
@@ -17,6 +17,9 @@ module.exports = function isIndexEqual(key, options, dbIndex) {
       continue;
     }
     if (key === 'collation') {
+      if (!(key in options) || !(key in dbIndex)) {
+        return false;
+      }
       const definedKeys = Object.keys(options.collation);
       const schemaCollation = options.collation;
       const dbCollation = dbIndex.collation;
@@ -45,4 +48,4 @@ module.exports = function isIndexEqual(key, options, dbIndex) {
   }
 
   return true;
-};
\ No newline at end of file
+};

From 9ec30b84e81a782aca91f9b85e4528bdea410118 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jul 2020 10:17:39 -0400
Subject: [PATCH 1054/2348] test: repro #9224

---
 test/helpers/indexes.isIndexEqual.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/helpers/indexes.isIndexEqual.test.js b/test/helpers/indexes.isIndexEqual.test.js
index 44a8df490c0..8184fd9b95f 100644
--- a/test/helpers/indexes.isIndexEqual.test.js
+++ b/test/helpers/indexes.isIndexEqual.test.js
@@ -33,4 +33,25 @@ describe('isIndexEqual', function() {
     dbIndex.collation.locale = 'de';
     assert.ok(!isIndexEqual(key, options, dbIndex));
   });
+
+  it('works when MongoDB index has collation but Mongoose index doesn\'t (gh-9224)', function() {
+    const key = { username: 1 };
+    const options = {};
+    const dbIndex = {
+      unique: true,
+      key: { username: 1 },
+      name: 'username_1',
+      background: true,
+      collation: {
+        locale: 'en',
+        caseLevel: false,
+        caseFirst: 'off',
+        strength: 2,
+        numericOrdering: false,
+        version: '57.1'
+      }
+    };
+
+    assert.ok(!isIndexEqual(key, options, dbIndex));
+  });
 });
\ No newline at end of file

From d4c8859950e0d5e6e84c03b2c8c2d38fbbbc7fee Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jul 2020 10:21:02 -0400
Subject: [PATCH 1055/2348] fix(model): fix `syncIndexes()` error when db index
 has a collation but Mongoose index does not

Fix #9224
---
 lib/helpers/indexes/isIndexEqual.js | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/indexes/isIndexEqual.js b/lib/helpers/indexes/isIndexEqual.js
index bbfe75f0df6..ae35a4123f8 100644
--- a/lib/helpers/indexes/isIndexEqual.js
+++ b/lib/helpers/indexes/isIndexEqual.js
@@ -3,6 +3,16 @@
 const get = require('../get');
 const utils = require('../../utils');
 
+/**
+ * Given a Mongoose index definition (key + options objects) and a MongoDB server
+ * index definition, determine if the two indexes are equal.
+ *
+ * @param {Object} key the Mongoose index spec
+ * @param {Object} options the Mongoose index definition's options
+ * @param {Object} dbIndex the index in MongoDB as returned by `listIndexes()`
+ * @api private
+ */
+
 module.exports = function isIndexEqual(key, options, dbIndex) {
   // If these options are different, need to rebuild the index
   const optionKeys = [
@@ -17,8 +27,8 @@ module.exports = function isIndexEqual(key, options, dbIndex) {
       continue;
     }
     if (key === 'collation') {
-      if (!(key in options) || !(key in dbIndex)) {
-        return false;
+      if (options.key == null || dbIndex.key == null) {
+        return options.key == null && dbIndex.key == null;
       }
       const definedKeys = Object.keys(options.collation);
       const schemaCollation = options.collation;

From 43288f869366ade4c287b4dd06e9c7016c6104c1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jul 2020 10:27:49 -0400
Subject: [PATCH 1056/2348] fix: fix typos that broke tests

---
 lib/helpers/indexes/isIndexEqual.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/indexes/isIndexEqual.js b/lib/helpers/indexes/isIndexEqual.js
index ae35a4123f8..ad3ef001cf6 100644
--- a/lib/helpers/indexes/isIndexEqual.js
+++ b/lib/helpers/indexes/isIndexEqual.js
@@ -27,8 +27,8 @@ module.exports = function isIndexEqual(key, options, dbIndex) {
       continue;
     }
     if (key === 'collation') {
-      if (options.key == null || dbIndex.key == null) {
-        return options.key == null && dbIndex.key == null;
+      if (options[key] == null || dbIndex[key] == null) {
+        return options[key] == null && dbIndex[key] == null;
       }
       const definedKeys = Object.keys(options.collation);
       const schemaCollation = options.collation;

From 79b4327697584eadab700f0543da6bd4fa63b9fc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 10 Jul 2020 13:42:37 -0400
Subject: [PATCH 1057/2348] chore: release 5.9.23

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index dc7267c5107..4eaec81c061 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.9.23 / 2020-07-10
+===================
+ * fix(model): fix `syncIndexes()` error when db index has a collation but Mongoose index does not #9224 [clhuang](https://github.com/clhuang)
+ * fix(array): only cast array to proper depth if it contains an non-array value #9217 #9215 [cyrilgandon](https://github.com/cyrilgandon)
+ * docs(schematype): document the `transform` option #9211
+ * docs(mongoose): fix typo #9212 [JNa0](https://github.com/JNa0)
+
 5.9.22 / 2020-07-06
 ===================
  * fix(schema): treat `{ type: mongoose.Schema.Types.Array }` as equivalent to `{ type: Array }` #9194
diff --git a/package.json b/package.json
index ff0175f5e70..b07aaffeb0a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.22",
+  "version": "5.9.23",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 40fc5e328744bd6fd284bb0a03eaea5748858b5b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Jul 2020 15:09:43 -0400
Subject: [PATCH 1058/2348] test(model): repro #9209

---
 test/model.hydrate.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.hydrate.test.js b/test/model.hydrate.test.js
index fb8896b27e8..ac50050a5b3 100644
--- a/test/model.hydrate.test.js
+++ b/test/model.hydrate.test.js
@@ -81,6 +81,22 @@ describe('model', function() {
       });
     });
 
+    it('supports projection (gh-9209)', function(done) {
+      const schema = new Schema({
+        prop: String,
+        arr: [String]
+      });
+      const Model = db.model('Test2', schema);
+
+      const doc = Model.hydrate({ prop: 'test' }, { arr: 0 });
+
+      assert.equal(doc.isNew, false);
+      assert.equal(doc.isModified(), false);
+      assert.ok(!doc.$__delta());
+
+      done();
+    });
+
     it('works correctly with model discriminators', function(done) {
       const hydrated = B.hydrate({ _id: '541085faedb2f28965d0e8e8', title: 'chair', type: 'C' });
 

From 386585e42746d029d8c855bfb08a5fabd63708db Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Jul 2020 15:10:35 -0400
Subject: [PATCH 1059/2348] fix(model): allow passing projection to
 `Model.hydrate()`

Fix #9209
---
 lib/model.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 34af9f5a98b..507eeb3bd96 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3529,14 +3529,15 @@ Model.bulkWrite = function(ops, options, callback) {
  *     var mongooseCandy = Candy.hydrate({ _id: '54108337212ffb6d459f854c', type: 'jelly bean' });
  *
  * @param {Object} obj
+ * @param {Object|String} [projection] optional projection containing which fields should be selected for this document
  * @return {Document} document instance
  * @api public
  */
 
-Model.hydrate = function(obj) {
+Model.hydrate = function(obj, projection) {
   _checkContext(this, 'hydrate');
 
-  const model = require('./queryhelpers').createModel(this, obj);
+  const model = require('./queryhelpers').createModel(this, obj, projection);
   model.init(obj);
   return model;
 };

From bd0d7b92fe509717db7897969cfc6fb4b36e6fa6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Jul 2020 15:38:26 -0400
Subject: [PATCH 1060/2348] test(document): repro #9208

---
 test/document.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 42e0db451a6..dc9d5391f39 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9027,4 +9027,29 @@ describe('document', function() {
       then(doc => Model.findById(doc)).
       then(doc => assert.strictEqual(doc.obj.key, 2));
   });
+
+  it('clears out priorDoc after overwriting single nested subdoc (gh-9208)', function() {
+    const TestModel = db.model('Test', Schema({
+      nested: Schema({
+        myBool: Boolean,
+        myString: String
+      })
+    }));
+
+    return co(function*() {
+      const test = new TestModel();
+
+      test.nested = { myBool: true };
+      yield test.save();
+
+      test.nested = { myString: 'asdf' };
+      yield test.save();
+
+      test.nested.myBool = true;
+      yield test.save();
+
+      const doc = yield TestModel.findById(test);
+      assert.strictEqual(doc.nested.myBool, true);
+    });
+  });
 });

From 35869a39fb5493fd813f2d24414e19c0fb1761d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 11 Jul 2020 15:40:05 -0400
Subject: [PATCH 1061/2348] fix(document): clear out `priorDoc` after
 overwriting single nested subdoc so changes after overwrite get persisted
 correctly

Fix #9208
---
 lib/types/subdocument.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 521237aee72..b015a091cf3 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -48,6 +48,8 @@ function Subdocument(value, fields, parent, skipId, options) {
         }
       }
     }
+
+    delete options.priorDoc;
   }
 }
 

From 9a23c4256b27c80e748df134f3c19dceffea1c05 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 12 Jul 2020 13:41:09 -0400
Subject: [PATCH 1062/2348] fix(connection): respect connection-level
 `bufferCommands` option if `mongoose.connect()` is called after
 `mongoose.model()`

Re: #9179
---
 lib/collection.js                             | 31 +++++++++++++++----
 lib/drivers/node-mongodb-native/collection.js |  5 ++-
 lib/model.js                                  | 28 ++---------------
 test/connection.test.js                       | 13 ++++++--
 test/index.test.js                            | 11 +++++--
 5 files changed, 50 insertions(+), 38 deletions(-)

diff --git a/lib/collection.js b/lib/collection.js
index b53709407f9..2f5d188b012 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -27,10 +27,6 @@ function Collection(name, conn, opts) {
     opts.capped = {};
   }
 
-  opts.bufferCommands = undefined === opts.bufferCommands
-    ? true
-    : opts.bufferCommands;
-
   if (typeof opts.capped === 'number') {
     opts.capped = { size: opts.capped };
   }
@@ -40,7 +36,7 @@ function Collection(name, conn, opts) {
   this.collectionName = name;
   this.conn = conn;
   this.queue = [];
-  this.buffer = this.opts.bufferCommands;
+  this.buffer = true;
   this.emitter = new EventEmitter();
 
   if (STATES.connected === this.conn.readyState) {
@@ -93,7 +89,7 @@ Collection.prototype.onOpen = function() {
  */
 
 Collection.prototype.onClose = function(force) {
-  if (this.opts.bufferCommands && !force) {
+  if (this._shouldBufferCommands() && !force) {
     this.buffer = true;
   }
 };
@@ -262,6 +258,29 @@ Collection.prototype.watch = function() {
   throw new Error('Collection#watch unimplemented by driver');
 };
 
+/*!
+ * ignore
+ */
+
+Collection.prototype._shouldBufferCommands = function _shouldBufferCommands() {
+  const conn = this.conn;
+  const opts = this.opts;
+
+  if (opts.bufferCommands != null) {
+    return opts.bufferCommands;
+  }
+  if (opts && opts.schemaUserProvidedOptions != null && opts.schemaUserProvidedOptions.bufferCommands != null) {
+    return opts.schemaUserProvidedOptions.bufferCommands;
+  }
+  if (conn.config.bufferCommands != null) {
+    return conn.config.bufferCommands;
+  }
+  if (conn.base != null && conn.base.get('bufferCommands') != null) {
+    return conn.base.get('bufferCommands');
+  }
+  return true;
+};
+
 /*!
  * Module exports.
  */
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index d868188ec3f..a8b844769ce 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -140,7 +140,7 @@ function iter(i) {
       }
     }
 
-    if (this.buffer) {
+    if (this._shouldBufferCommands() && this.buffer) {
       if (syncCollectionMethods[i]) {
         throw new Error('Collection method ' + i + ' is synchronous');
       }
@@ -148,6 +148,9 @@ function iter(i) {
         this.addQueue(i, args);
         return;
       }
+
+      this.conn.emit('buffer', { method: i, args: args });
+
       return new this.Promise((resolve, reject) => {
         this.addQueue(i, [].concat(args).concat([(err, res) => {
           if (err != null) {
diff --git a/lib/model.js b/lib/model.js
index 507eeb3bd96..fd88fd7638a 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4737,23 +4737,8 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
 
   const _userProvidedOptions = schema._userProvidedOptions || {};
 
-  // `bufferCommands` is true by default...
-  let bufferCommands = true;
-  // First, take the global option
-  if (connection.base.get('bufferCommands') != null) {
-    bufferCommands = connection.base.get('bufferCommands');
-  }
-  // Connection-specific overrides the global option
-  if (connection.config.bufferCommands != null) {
-    bufferCommands = connection.config.bufferCommands;
-  }
-  // And schema options override global and connection
-  if (_userProvidedOptions.bufferCommands != null) {
-    bufferCommands = _userProvidedOptions.bufferCommands;
-  }
-
   const collectionOptions = {
-    bufferCommands: bufferCommands,
+    schemaUserProvidedOptions: _userProvidedOptions,
     capped: schema.options.capped,
     autoCreate: schema.options.autoCreate,
     Promise: model.base.Promise
@@ -4847,17 +4832,8 @@ Model.__subclass = function subclass(conn, schema, collection) {
       utils.toCollectionName(_this.modelName, this.base.pluralize());
   }
 
-  let bufferCommands = true;
-  if (s) {
-    if (conn.config.bufferCommands != null) {
-      bufferCommands = conn.config.bufferCommands;
-    }
-    if (_userProvidedOptions.bufferCommands != null) {
-      bufferCommands = _userProvidedOptions.bufferCommands;
-    }
-  }
   const collectionOptions = {
-    bufferCommands: bufferCommands,
+    schemaUserProvidedOptions: _userProvidedOptions,
     capped: s && options.capped
   };
 
diff --git a/test/connection.test.js b/test/connection.test.js
index f259e6d590f..fadb4f3d67e 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -715,19 +715,26 @@ describe('connections:', function() {
     let db = mongoose.createConnection('mongodb://localhost:27017/test', opts);
 
     let M = db.model('gh5720', new Schema({}));
-    assert.ok(!M.collection.buffer);
+    assert.ok(!M.collection._shouldBufferCommands());
     db.close();
 
     opts = { bufferCommands: true };
     db = mongoose.createConnection('mongodb://localhost:27017/test', opts);
     M = db.model('gh5720', new Schema({}, { bufferCommands: false }));
-    assert.ok(!M.collection.buffer);
+    assert.ok(!M.collection._shouldBufferCommands());
     db.close();
 
     opts = { bufferCommands: true };
     db = mongoose.createConnection('mongodb://localhost:27017/test', opts);
     M = db.model('gh5720', new Schema({}));
-    assert.ok(M.collection.buffer);
+    assert.ok(M.collection._shouldBufferCommands());
+
+    db = mongoose.createConnection();
+    M = db.model('gh5720', new Schema({}));
+    opts = { bufferCommands: false };
+    db.openUri('mongodb://localhost:27017/test', opts);
+    assert.ok(!M.collection._shouldBufferCommands());
+
     db.close(done);
   });
 
diff --git a/test/index.test.js b/test/index.test.js
index 5d4c85e6c51..19f9fd8fb7b 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -122,14 +122,21 @@ describe('mongoose module:', function() {
     assert.strictEqual(mongoose.options.bufferCommands, false);
   });
 
-  it('bufferCommands option (gh-5879)', function() {
+  it('bufferCommands option (gh-5879) (gh-9179)', function() {
     const mongoose = new Mongoose();
 
     mongoose.set('bufferCommands', false);
 
     const M = mongoose.model('Test', new Schema({}));
 
-    assert.ok(!M.collection.buffer);
+    assert.ok(!M.collection._shouldBufferCommands());
+
+    // Allow changing bufferCommands after defining model (gh-9179)
+    mongoose.set('bufferCommands', true);
+    assert.ok(M.collection._shouldBufferCommands());
+
+    mongoose.set('bufferCommands', false);
+    assert.ok(!M.collection._shouldBufferCommands());
   });
 
   it('cloneSchemas option (gh-6274)', function() {

From f88eb2524b65a68ff893c90a03c04f0913c1913e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 12 Jul 2020 13:53:04 -0400
Subject: [PATCH 1063/2348] fix(query): delete top-level `_bsontype` property
 in queries to prevent silent empty queries

Backport fix for #8222
Fix #8241
---
 lib/cast.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/cast.js b/lib/cast.js
index 7f475edfeb4..339c031f14d 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -23,6 +23,12 @@ module.exports = function cast(schema, obj, options, context) {
     throw new Error('Query filter must be an object, got an array ', util.inspect(obj));
   }
 
+  // bson 1.x has the unfortunate tendency to remove filters that have a top-level
+  // `_bsontype` property. Should remove this when we upgrade to bson 4.x. See gh-8222
+  if (obj.hasOwnProperty('_bsontype')) {
+    delete obj._bsontype;
+  }
+
   var paths = Object.keys(obj);
   var i = paths.length;
   var _keys;

From 7b11d702bfe9185ff109c0e4f118ea7b6d5310c7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 12 Jul 2020 13:57:33 -0400
Subject: [PATCH 1064/2348] chore: release 4.13.21

---
 History.md   | 4 ++++
 package.json | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 294b1e0ce5c..e29a60a51ee 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,7 @@
+4.13.21 / 2020-07-12
+====================
+ * fix(query): delete top-level `_bsontype` property in queries to prevent silent empty queries #8222
+
 4.13.20 / 2020-01-07
 ====================
  * fix(schema): make aliases handle mongoose-lean-virtuals #6069
diff --git a/package.json b/package.json
index 006b5373612..d5ad3f2be82 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "4.13.20",
+  "version": "4.13.21",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 423acb4a2d03fc5803e04ab5443fb99d73507ab7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 13 Jul 2020 10:26:14 -0400
Subject: [PATCH 1065/2348] fix(connection): dont overwrite user-specified
 `bufferMaxEntries` when setting `bufferCommands`

Fix #9218
---
 lib/connection.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index c64e192c1f9..0123c00bf5c 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -631,7 +631,9 @@ Connection.prototype.openUri = function(uri, options, callback) {
     delete options.pass;
 
     if (options.bufferCommands != null) {
-      options.bufferMaxEntries = 0;
+      if (options.bufferMaxEntries == null) {
+        options.bufferMaxEntries = 0;
+      }
       this.config.bufferCommands = options.bufferCommands;
       delete options.bufferCommands;
     }

From 4de0417762cc149e7f15c53368bfdb8803d75387 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 13 Jul 2020 11:47:44 -0400
Subject: [PATCH 1066/2348] docs(model): make `find` and `findOne()` examples
 use async/await and clarify `find({})` is find all

Fix #9210
---
 lib/model.js | 71 ++++++++++++++--------------------------------------
 1 file changed, 19 insertions(+), 52 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index fd88fd7638a..43c2fd586b6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1976,35 +1976,26 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
 /**
  * Finds documents.
  *
- * The `filter` are cast to their respective SchemaTypes before the command is sent.
+ * Mongoose casts the `filter` to match the model's schema before the command is sent.
  * See our [query casting tutorial](/docs/tutorials/query_casting.html) for
  * more information on how Mongoose casts `filter`.
  *
  * ####Examples:
  *
- *     // named john and at least 18
- *     MyModel.find({ name: 'john', age: { $gte: 18 }});
+ *     // find all documents
+ *     await MyModel.find({});
+ *
+ *     // find all documents named john and at least 18
+ *     await MyModel.find({ name: 'john', age: { $gte: 18 } }).exec();
  *
  *     // executes, passing results to callback
  *     MyModel.find({ name: 'john', age: { $gte: 18 }}, function (err, docs) {});
  *
  *     // executes, name LIKE john and only selecting the "name" and "friends" fields
- *     MyModel.find({ name: /john/i }, 'name friends', function (err, docs) { })
+ *     await MyModel.find({ name: /john/i }, 'name friends').exec();
  *
  *     // passing options
- *     MyModel.find({ name: /john/i }, null, { skip: 10 })
- *
- *     // passing options and executes
- *     MyModel.find({ name: /john/i }, null, { skip: 10 }, function (err, docs) {});
- *
- *     // executing a query explicitly
- *     var query = MyModel.find({ name: /john/i }, null, { skip: 10 })
- *     query.exec(function (err, docs) {});
- *
- *     // using the promise returned from executing a query
- *     var query = MyModel.find({ name: /john/i }, null, { skip: 10 });
- *     var promise = query.exec();
- *     promise.addBack(function (err, docs) {});
+ *     await MyModel.find({ name: /john/i }, null, { skip: 10 }).exec();
  *
  * @param {Object|ObjectId} filter
  * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](http://mongoosejs.com/docs/api.html#query_Query-select)
@@ -2067,26 +2058,14 @@ Model.find = function find(conditions, projection, options, callback) {
  *
  * ####Example:
  *
- *     // find adventure by id and execute
- *     Adventure.findById(id, function (err, adventure) {});
+ *     // Find the adventure with the given `id`, or `null` if not found
+ *     await Adventure.findById(id).exec();
  *
- *     // same as above
- *     Adventure.findById(id).exec(callback);
+ *     // using callback
+ *     Adventure.findById(id, function (err, adventure) {});
  *
  *     // select only the adventures name and length
- *     Adventure.findById(id, 'name length', function (err, adventure) {});
- *
- *     // same as above
- *     Adventure.findById(id, 'name length').exec(callback);
- *
- *     // include all properties except for `length`
- *     Adventure.findById(id, '-length').exec(function (err, adventure) {});
- *
- *     // passing options (in this case return the raw js objects, not mongoose documents by passing `lean`
- *     Adventure.findById(id, 'name', { lean: true }, function (err, doc) {});
- *
- *     // same as above
- *     Adventure.findById(id, 'name').lean().exec(function (err, doc) {});
+ *     await Adventure.findById(id, 'name length').exec();
  *
  * @param {Any} id value of `_id` to query by
  * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
@@ -2122,26 +2101,14 @@ Model.findById = function findById(id, projection, options, callback) {
  *
  * ####Example:
  *
- *     // find one iphone adventures - iphone adventures??
- *     Adventure.findOne({ type: 'iphone' }, function (err, adventure) {});
- *
- *     // same as above
- *     Adventure.findOne({ type: 'iphone' }).exec(function (err, adventure) {});
- *
- *     // select only the adventures name
- *     Adventure.findOne({ type: 'iphone' }, 'name', function (err, adventure) {});
+ *     // Find one adventure whose `country` is 'Croatia', otherwise `null`
+ *     await Adventure.findOne({ country: 'Croatia' }).exec();
  *
- *     // same as above
- *     Adventure.findOne({ type: 'iphone' }, 'name').exec(function (err, adventure) {});
+ *     // using callback
+ *     Adventure.findOne({ country: 'Croatia' }, function (err, adventure) {});
  *
- *     // specify options, in this case lean
- *     Adventure.findOne({ type: 'iphone' }, 'name', { lean: true }, callback);
- *
- *     // same as above
- *     Adventure.findOne({ type: 'iphone' }, 'name', { lean: true }).exec(callback);
- *
- *     // chaining findOne queries (same as above)
- *     Adventure.findOne({ type: 'iphone' }).select('name').lean().exec(callback);
+ *     // select only the adventures name and length
+ *     await Adventure.findOne({ country: 'Croatia' }, 'name length').exec();
  *
  * @param {Object} [conditions]
  * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)

From 415ba3de0486727209f6c2ffc9d6edd360235fc2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 13 Jul 2020 14:59:04 -0400
Subject: [PATCH 1067/2348] fix(schema+document): support adding `null` to
 schema boolean's `convertToFalse` set

Fix #9223
---
 lib/cast/boolean.js   |  9 ++++---
 lib/document.js       |  2 +-
 lib/schema/boolean.js | 21 +++++++++++++++
 lib/schematype.js     | 10 ++++++-
 test/document.test.js | 61 +++++++++++++++++++++++++++++++------------
 5 files changed, 81 insertions(+), 22 deletions(-)

diff --git a/lib/cast/boolean.js b/lib/cast/boolean.js
index 4843e1f70b5..92551d41e3e 100644
--- a/lib/cast/boolean.js
+++ b/lib/cast/boolean.js
@@ -14,16 +14,17 @@ const CastError = require('../error/cast');
  */
 
 module.exports = function castBoolean(value, path) {
-  if (value == null) {
-    return value;
-  }
-
   if (module.exports.convertToTrue.has(value)) {
     return true;
   }
   if (module.exports.convertToFalse.has(value)) {
     return false;
   }
+
+  if (value == null) {
+    return value;
+  }
+
   throw new CastError('boolean', value, path);
 };
 
diff --git a/lib/document.js b/lib/document.js
index a8614bbb749..5336b8f723e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -641,7 +641,7 @@ function init(self, obj, doc, opts, prefix) {
       doc[i] = obj[i];
     } else {
       if (obj[i] === null) {
-        doc[i] = null;
+        doc[i] = schema._castNullish(null);
       } else if (obj[i] !== undefined) {
         const intCache = obj[i].$__ || {};
         const wasPopulated = intCache.wasPopulated || null;
diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 4280d941f7e..b56c52b039e 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -224,6 +224,27 @@ SchemaBoolean.prototype.castForQuery = function($conditional, val) {
   return this._castForQuery($conditional);
 };
 
+/**
+ *
+ * @api private
+ */
+
+SchemaBoolean.prototype._castNullish = function _castNullish(v) {
+  const castBoolean = typeof this.constructor.cast === 'function' ?
+    this.constructor.cast() :
+    SchemaBoolean.cast();
+  if (castBoolean == null) {
+    return null;
+  }
+  if (castBoolean.convertToFalse instanceof Set && castBoolean.convertToFalse.has(v)) {
+    return false;
+  }
+  if (castBoolean.convertToTrue instanceof Set && castBoolean.convertToTrue.has(v)) {
+    return true;
+  }
+  return null;
+};
+
 /*!
  * Module exports.
  */
diff --git a/lib/schematype.js b/lib/schematype.js
index 3edff125edc..08f48356a9a 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1043,6 +1043,14 @@ SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
   return v;
 };
 
+/*!
+ * ignore
+ */
+
+SchemaType.prototype._castNullish = function _castNullish(v) {
+  return v;
+};
+
 /**
  * Applies setters
  *
@@ -1056,7 +1064,7 @@ SchemaType.prototype.applySetters = function(value, scope, init, priorVal, optio
   let v = this._applySetters(value, scope, init, priorVal, options);
 
   if (v == null) {
-    return v;
+    return this._castNullish(v);
   }
 
   // do not cast until all setters are applied #665
diff --git a/test/document.test.js b/test/document.test.js
index dc9d5391f39..01dc74ae3f3 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -6309,26 +6309,55 @@ describe('document', function() {
       });
     });
 
-    it('convertToFalse and convertToTrue (gh-6758)', function() {
-      const TestSchema = new Schema({ b: Boolean });
-      const Test = db.model('Test', TestSchema);
+    describe('convertToFalse and convertToTrue (gh-6758)', function() {
+      let convertToFalse = null;
+      let convertToTrue = null;
+
+      beforeEach(function() {
+        convertToFalse = new Set(mongoose.Schema.Types.Boolean.convertToFalse);
+        convertToTrue = new Set(mongoose.Schema.Types.Boolean.convertToTrue);
+      });
 
-      mongoose.Schema.Types.Boolean.convertToTrue.add('aye');
-      mongoose.Schema.Types.Boolean.convertToFalse.add('nay');
+      afterEach(function() {
+        mongoose.Schema.Types.Boolean.convertToFalse = convertToFalse;
+        mongoose.Schema.Types.Boolean.convertToTrue = convertToTrue;
+      });
 
-      const doc1 = new Test({ b: 'aye' });
-      const doc2 = new Test({ b: 'nay' });
+      it('lets you add custom strings that get converted to true/false', function() {
+        const TestSchema = new Schema({ b: Boolean });
+        const Test = db.model('Test', TestSchema);
 
-      assert.strictEqual(doc1.b, true);
-      assert.strictEqual(doc2.b, false);
+        mongoose.Schema.Types.Boolean.convertToTrue.add('aye');
+        mongoose.Schema.Types.Boolean.convertToFalse.add('nay');
 
-      return doc1.save().
-        then(() => Test.findOne({ b: { $exists: 'aye' } })).
-        then(doc => assert.ok(doc)).
-        then(() => {
-          mongoose.Schema.Types.Boolean.convertToTrue.delete('aye');
-          mongoose.Schema.Types.Boolean.convertToFalse.delete('nay');
-        });
+        const doc1 = new Test({ b: 'aye' });
+        const doc2 = new Test({ b: 'nay' });
+
+        assert.strictEqual(doc1.b, true);
+        assert.strictEqual(doc2.b, false);
+
+        return doc1.save().
+          then(() => Test.findOne({ b: { $exists: 'aye' } })).
+          then(doc => assert.ok(doc)).
+          then(() => {
+            mongoose.Schema.Types.Boolean.convertToTrue.delete('aye');
+            mongoose.Schema.Types.Boolean.convertToFalse.delete('nay');
+          });
+      });
+
+      it('allows adding `null` to list of values that convert to false (gh-9223)', function() {
+        const TestSchema = new Schema({ b: Boolean });
+        const Test = db.model('Test', TestSchema);
+
+        mongoose.Schema.Types.Boolean.convertToFalse.add(null);
+
+        const doc1 = new Test({ b: null });
+        const doc2 = new Test();
+        doc2.init({ b: null });
+
+        assert.strictEqual(doc1.b, false);
+        assert.strictEqual(doc2.b, false);
+      });
     });
 
     it('doesnt double-call getters when using get() (gh-6779)', function() {

From 02bef0eb51d560d243a80aee123d5a27e0cf39fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 13 Jul 2020 15:11:28 -0400
Subject: [PATCH 1068/2348] chore: release 5.9.24

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 782171d4336..ba0f2e90f44 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.9.24 / 2020-07-13
+===================
+ * fix(connection): respect connection-level `bufferCommands` option if `mongoose.connect()` is called after `mongoose.model()` #9179
+ * fix(document): clear out `priorDoc` after overwriting single nested subdoc so changes after overwrite get persisted correctly #9208
+ * fix(connection): dont overwrite user-specified `bufferMaxEntries` when setting `bufferCommands` #9218
+ * fix(model): allow passing projection to `Model.hydrate()` #9209
+ * fix(schema+document): support adding `null` to schema boolean's `convertToFalse` set #9223
+ * docs(model): make `find` and `findOne()` examples use async/await and clarify `find({})` is find all #9210
+
 4.13.21 / 2020-07-12
 ====================
  * fix(query): delete top-level `_bsontype` property in queries to prevent silent empty queries #8222
diff --git a/package.json b/package.json
index b07aaffeb0a..da742beb505 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.23",
+  "version": "5.9.24",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From cb71c852fdd6baf0261e5b0651243d077f4a3fc5 Mon Sep 17 00:00:00 2001
From: Eugene Maslovich <ehpc@em42.ru>
Date: Wed, 15 Jul 2020 11:26:29 +0300
Subject: [PATCH 1069/2348] Make Boolean _castNullish respect omitUndefined

Proposed fix for https://github.com/Automattic/mongoose/issues/9242
---
 lib/schema/boolean.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index b56c52b039e..3c3c7cf187d 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -230,6 +230,9 @@ SchemaBoolean.prototype.castForQuery = function($conditional, val) {
  */
 
 SchemaBoolean.prototype._castNullish = function _castNullish(v) {
+  if (typeof v === 'undefined' && this.$$context._mongooseOptions.omitUndefined) {
+    return v;
+  }
   const castBoolean = typeof this.constructor.cast === 'function' ?
     this.constructor.cast() :
     SchemaBoolean.cast();

From 62f15b1439621c583be1316c3d2370171805c1ff Mon Sep 17 00:00:00 2001
From: JNa0 <florian.monfort@etudiant.univ-rennes1.fr>
Date: Wed, 15 Jul 2020 20:50:37 +0200
Subject: [PATCH 1070/2348] correction of typo

missing backticks l. 263 and l. 325
---
 lib/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 1b201b110e8..a1071653faf 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -260,7 +260,7 @@ Mongoose.prototype.get = Mongoose.prototype.set;
  * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
- * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
+ * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0`, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
  * @return {Connection} the created Connection object. Connections are thenable, so you can do `await mongoose.createConnection()`
  * @api public
  */
@@ -322,7 +322,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
- * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
+ * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0`, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
  * @param {Function} [callback]
  * @see Mongoose#createConnection #index_Mongoose-createConnection
  * @api public

From dca584e5ee3c5ce2faff1c4b07a51130e7f49505 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 15 Jul 2020 18:08:40 -0400
Subject: [PATCH 1071/2348] test(indexes): repro #9225

---
 test/helpers/indexes.isIndexEqual.test.js | 28 +++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/helpers/indexes.isIndexEqual.test.js b/test/helpers/indexes.isIndexEqual.test.js
index 8184fd9b95f..b45ef39fa52 100644
--- a/test/helpers/indexes.isIndexEqual.test.js
+++ b/test/helpers/indexes.isIndexEqual.test.js
@@ -54,4 +54,32 @@ describe('isIndexEqual', function() {
 
     assert.ok(!isIndexEqual(key, options, dbIndex));
   });
+
+  it('handles text indexes (gh-9225)', function() {
+    const key = { name: 'text' };
+    const options = {};
+    const dbIndex = {
+      v: 2,
+      key: { _fts: 'text', _ftsx: 1 },
+      name: 'name_text',
+      ns: 'test.tests',
+      background: true,
+      weights: { name: 1 },
+      default_language: 'english',
+      language_override: 'language',
+      textIndexVersion: 3
+    };
+
+    assert.ok(isIndexEqual(key, options, dbIndex));
+
+    key.otherProp = 'text';
+    assert.ok(!isIndexEqual(key, options, dbIndex));
+
+    delete key.otherProp;
+    options.weights = { name: 2 };
+    assert.ok(!isIndexEqual(key, options, dbIndex));
+
+    options.weights.name = 1;
+    assert.ok(isIndexEqual(key, options, dbIndex));
+  });
 });
\ No newline at end of file

From 996daa34d37d5715d88d08628ececcbe4714f458 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 15 Jul 2020 18:09:07 -0400
Subject: [PATCH 1072/2348] fix(indexes): don't unnecessarily drop text indexes
 when running `syncIndexes()`

Fix #9225
---
 lib/helpers/indexes/isIndexEqual.js | 36 ++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/indexes/isIndexEqual.js b/lib/helpers/indexes/isIndexEqual.js
index ad3ef001cf6..d59d73438fc 100644
--- a/lib/helpers/indexes/isIndexEqual.js
+++ b/lib/helpers/indexes/isIndexEqual.js
@@ -14,7 +14,41 @@ const utils = require('../../utils');
  */
 
 module.exports = function isIndexEqual(key, options, dbIndex) {
-  // If these options are different, need to rebuild the index
+  // Special case: text indexes have a special format in the db. For example,
+  // `{ name: 'text' }` becomes:
+  // {
+  //   v: 2,
+  //   key: { _fts: 'text', _ftsx: 1 },
+  //   name: 'name_text',
+  //   ns: 'test.tests',
+  //   background: true,
+  //   weights: { name: 1 },
+  //   default_language: 'english',
+  //   language_override: 'language',
+  //   textIndexVersion: 3
+  // }
+  if (dbIndex.textIndexVersion != null) {
+    const weights = dbIndex.weights;
+    if (Object.keys(weights).length !== Object.keys(key).length) {
+      return false;
+    }
+    for (const prop of Object.keys(weights)) {
+      if (!(prop in key)) {
+        return false;
+      }
+      const weight = weights[prop];
+      if (weight !== get(options, 'weights.' + prop) && !(weight === 1 && get(options, 'weights.' + prop) == null)) {
+        return false;
+      }
+    }
+
+    if (options['default_language'] !== dbIndex['default_language']) {
+      return dbIndex['default_language'] === 'english' && options['default_language'] == null;
+    }
+
+    return true;
+  }
+
   const optionKeys = [
     'unique',
     'partialFilterExpression',

From 524ae0afd8eb56b9c9af40e2fb84a037c2e10512 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 16 Jul 2020 12:59:36 -0400
Subject: [PATCH 1073/2348] fix(connection): throw more readable error when
 querying db before initial connection when `bufferCommands = false`

Fix #9239
---
 lib/drivers/node-mongodb-native/collection.js | 59 +++++++++----------
 test/connection.test.js                       |  5 +-
 2 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index a8b844769ce..290a0355aad 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -42,59 +42,54 @@ NativeCollection.prototype.__proto__ = MongooseCollection.prototype;
 
 NativeCollection.prototype.onOpen = function() {
   const _this = this;
+  this.collection = this.conn.db.collection(this.name);
 
   // always get a new collection in case the user changed host:port
   // of parent db instance when re-opening the connection.
 
   if (!_this.opts.capped.size) {
     // non-capped
-    callback(null, _this.conn.db.collection(_this.name));
+    callback(null);
     return _this.collection;
   }
 
   if (_this.opts.autoCreate === false) {
-    _this.collection = _this.conn.db.collection(_this.name);
     return _this.collection;
   }
 
   // capped
-  return _this.conn.db.collection(_this.name, function(err, c) {
-    if (err) return callback(err);
+  // discover if this collection exists and if it is capped
+  _this.conn.db.listCollections({ name: _this.name }).toArray(function(err, docs) {
+    if (err) {
+      return callback(err);
+    }
+    const doc = docs[0];
+    const exists = !!doc;
 
-    // discover if this collection exists and if it is capped
-    _this.conn.db.listCollections({ name: _this.name }).toArray(function(err, docs) {
-      if (err) {
-        return callback(err);
-      }
-      const doc = docs[0];
-      const exists = !!doc;
-
-      if (exists) {
-        if (doc.options && doc.options.capped) {
-          callback(null, c);
-        } else {
-          const msg = 'A non-capped collection exists with the name: ' + _this.name + '\n\n'
-              + ' To use this collection as a capped collection, please '
-              + 'first convert it.\n'
-              + ' http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-Convertingacollectiontocapped';
-          err = new Error(msg);
-          callback(err);
-        }
+    if (exists) {
+      if (doc.options && doc.options.capped) {
+        callback(null);
       } else {
-        // create
-        const opts = Object.assign({}, _this.opts.capped);
-        opts.capped = true;
-        _this.conn.db.createCollection(_this.name, opts, callback);
+        const msg = 'A non-capped collection exists with the name: ' + _this.name + '\n\n'
+            + ' To use this collection as a capped collection, please '
+            + 'first convert it.\n'
+            + ' http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-Convertingacollectiontocapped';
+        err = new Error(msg);
+        callback(err);
       }
-    });
+    } else {
+      // create
+      const opts = Object.assign({}, _this.opts.capped);
+      opts.capped = true;
+      callback(null);
+    }
   });
 
-  function callback(err, collection) {
+  function callback(err) {
     if (err) {
       // likely a strict mode error
       _this.conn.emit('error', err);
     } else {
-      _this.collection = collection;
       MongooseCollection.prototype.onOpen.call(_this);
     }
   }
@@ -173,6 +168,10 @@ function iter(i) {
     }
 
     try {
+      if (collection == null) {
+        throw new MongooseError('Cannot call `' + this.name + '.' + i + '()` before initial connection is complete if `bufferCommands = false`. Make sure you `await mongoose.connect()` if you have `bufferCommands = false`.');
+      }
+
       return collection[i].apply(collection, args);
     } catch (error) {
       // Collection operation may throw because of max bson size, catch it here
diff --git a/test/connection.test.js b/test/connection.test.js
index fadb4f3d67e..a8a169ce8c9 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -710,7 +710,7 @@ describe('connections:', function() {
     });
   });
 
-  it('bufferCommands (gh-5720)', function(done) {
+  it('bufferCommands (gh-5720)', function() {
     let opts = { bufferCommands: false };
     let db = mongoose.createConnection('mongodb://localhost:27017/test', opts);
 
@@ -735,7 +735,8 @@ describe('connections:', function() {
     db.openUri('mongodb://localhost:27017/test', opts);
     assert.ok(!M.collection._shouldBufferCommands());
 
-    db.close(done);
+    return M.findOne().then(() => assert.ok(false), err => assert.ok(err.message.includes('initial connection'))).
+      then(() => db.close());
   });
 
   it('dbName option (gh-6106)', function() {

From 5a1d2cb7a71a7b7c515cdd7b521f4c06dacef0f4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 10:42:07 -0400
Subject: [PATCH 1074/2348] test(populate): repro #9244

---
 test/model.populate.test.js | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index eaf15e3df71..972a853bb51 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9546,4 +9546,40 @@ describe('model: populate:', function() {
       assert.equal(docs[1].items[0].foo.title, 'doc1');
     });
   });
+
+  it('populates single nested discriminator underneath doc array when populated docs have different model but same id (gh-9244)', function() {
+    const catSchema = Schema({ _id: Number, name: String });
+    const dogSchema = Schema({ _id: Number, name: String });
+
+    const notificationSchema = Schema({ title: String }, { discriminatorKey: 'type' });
+    const notificationTypeASchema = Schema({
+      subject: {
+        type: Number,
+        ref: 'Cat'
+      }
+    }, { discriminatorKey: 'type' });
+    const notificationTypeBSchema = Schema({
+      subject: {
+        type: Number,
+        ref: 'Dog'
+      }
+    }, { discriminatorKey: 'type' });
+
+    const CatModel = db.model('Cat', catSchema);
+    const DogModel = db.model('Dog', dogSchema);
+    const NotificationModel = db.model('Notification', notificationSchema);
+    const NotificationTypeAModel = NotificationModel.discriminator('NotificationTypeA', notificationTypeASchema);
+    const NotificationTypeBModel = NotificationModel.discriminator('NotificationTypeB', notificationTypeBSchema);
+
+    return co(function*() {
+      const cat = yield CatModel.create({ _id: 1, name: 'Keanu' });
+      const dog = yield DogModel.create({ _id: 1, name: 'Bud' });
+
+      yield NotificationTypeAModel.create({ subject: cat._id, title: 'new cat' });
+      yield NotificationTypeBModel.create({ subject: dog._id, title: 'new dog' });
+
+      const notifications = yield NotificationModel.find({}).populate('subject');
+      assert.deepEqual(notifications.map(el => el.subject.name), ['Keanu', 'Bud']);
+    });
+  });
 });

From bc5f6ded5970212ba9f49096d630eb0a1c7a2124 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 10:42:34 -0400
Subject: [PATCH 1075/2348] fix(populate): populate single nested discriminator
 underneath doc array when populated docs have different model but same id

Fix #9244
---
 lib/helpers/populate/assignVals.js            | 26 ++++++++++++++++---
 .../populate/getModelsMapForPopulate.js       |  6 +++++
 lib/model.js                                  | 16 +++++++++---
 3 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index bd93e81afdc..948d8151222 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -18,6 +18,7 @@ module.exports = function assignVals(o) {
     justOne: o.justOne
   });
   populateOptions.$nullIfNotFound = o.isVirtual;
+  const populatedModel = o.populatedModel;
 
   const originalIds = [].concat(o.rawIds);
 
@@ -39,12 +40,31 @@ module.exports = function assignVals(o) {
     if (val instanceof SkipPopulateValue) {
       return val.val;
     }
+
     if (o.justOne === true && Array.isArray(val)) {
-      return valueFilter(val[0], options, populateOptions);
+      // Might be an embedded discriminator (re: gh-9244) with multiple models, so make sure to pick the right
+      // model before assigning.
+      const ret = [];
+      for (const doc of val) {
+        const _docPopulatedModel = leanPopulateMap.get(doc);
+        if (_docPopulatedModel == null || _docPopulatedModel === populatedModel) {
+          ret.push(doc);
+        }
+      }
+      // Since we don't want to have to create a new mongoosearray, make sure to
+      // modify the array in place
+      while (val.length > ret.length) {
+        Array.prototype.pop.apply(val, []);
+      }
+      for (let i = 0; i < ret.length; ++i) {
+        val[i] = ret[i];
+      }
+
+      return valueFilter(val[0], options, populateOptions, populatedModel);
     } else if (o.justOne === false && !Array.isArray(val)) {
-      return valueFilter([val], options, populateOptions);
+      return valueFilter([val], options, populateOptions, populatedModel);
     }
-    return valueFilter(val, options, populateOptions);
+    return valueFilter(val, options, populateOptions, populatedModel);
   }
 
   for (let i = 0; i < docs.length; ++i) {
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 438eeee78d0..9c634fb67c6 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -194,6 +194,12 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     const localFieldGetters = localFieldPath && localFieldPath.getters ? localFieldPath.getters : [];
     let ret;
 
+    if (localFieldPathType != null && schema == null && justOne == null) {
+      justOne = Array.isArray(localFieldPathType) ?
+        localFieldPathType.every(schema => !schema.$isMongooseArray) :
+        !localFieldPathType.$isMongooseArray;
+    }
+
     const _populateOptions = get(options, 'options', {});
 
     const getters = 'getters' in _populateOptions ?
diff --git a/lib/model.js b/lib/model.js
index 43c2fd586b6..a0c1b71f3ef 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4489,7 +4489,16 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
     query.populate(subPopulate);
   }
 
-  query.exec(callback);
+  query.exec((err, docs) => {
+    if (err != null) {
+      return callback(err);
+    }
+    for (const val of docs) {
+      leanPopulateMap.set(val, mod.model);
+    }
+
+    callback(null, docs);
+  });
 }
 
 /*!
@@ -4566,9 +4575,7 @@ function _assign(model, vals, mod, assignmentOpts) {
         }
       }
       // flag each as result of population
-      if (lean) {
-        leanPopulateMap.set(val, mod.model);
-      } else {
+      if (!lean) {
         val.$__.wasPopulated = true;
       }
     }
@@ -4588,6 +4595,7 @@ function _assign(model, vals, mod, assignmentOpts) {
     justOne: mod.justOne,
     isVirtual: mod.isVirtual,
     allOptions: mod,
+    populatedModel: mod.model,
     lean: lean,
     virtual: mod.virtual,
     count: mod.count,

From ac65c4fffcc7b505dac1e0fae29e9d10f8ec7ea6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 10:55:00 -0400
Subject: [PATCH 1076/2348] fix(collection): fix test re: #9239

---
 lib/drivers/node-mongodb-native/collection.js | 55 ++++++++++---------
 1 file changed, 30 insertions(+), 25 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 290a0355aad..d660c7de51c 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -42,54 +42,59 @@ NativeCollection.prototype.__proto__ = MongooseCollection.prototype;
 
 NativeCollection.prototype.onOpen = function() {
   const _this = this;
-  this.collection = this.conn.db.collection(this.name);
 
   // always get a new collection in case the user changed host:port
   // of parent db instance when re-opening the connection.
 
   if (!_this.opts.capped.size) {
     // non-capped
-    callback(null);
+    callback(null, _this.conn.db.collection(_this.name));
     return _this.collection;
   }
 
   if (_this.opts.autoCreate === false) {
+    _this.collection = _this.conn.db.collection(_this.name);
     return _this.collection;
   }
 
   // capped
-  // discover if this collection exists and if it is capped
-  _this.conn.db.listCollections({ name: _this.name }).toArray(function(err, docs) {
-    if (err) {
-      return callback(err);
-    }
-    const doc = docs[0];
-    const exists = !!doc;
+  return _this.conn.db.collection(_this.name, function(err, c) {
+    if (err) return callback(err);
 
-    if (exists) {
-      if (doc.options && doc.options.capped) {
-        callback(null);
+    // discover if this collection exists and if it is capped
+    _this.conn.db.listCollections({ name: _this.name }).toArray(function(err, docs) {
+      if (err) {
+        return callback(err);
+      }
+      const doc = docs[0];
+      const exists = !!doc;
+
+      if (exists) {
+        if (doc.options && doc.options.capped) {
+          callback(null, c);
+        } else {
+          const msg = 'A non-capped collection exists with the name: ' + _this.name + '\n\n'
+              + ' To use this collection as a capped collection, please '
+              + 'first convert it.\n'
+              + ' http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-Convertingacollectiontocapped';
+          err = new Error(msg);
+          callback(err);
+        }
       } else {
-        const msg = 'A non-capped collection exists with the name: ' + _this.name + '\n\n'
-            + ' To use this collection as a capped collection, please '
-            + 'first convert it.\n'
-            + ' http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-Convertingacollectiontocapped';
-        err = new Error(msg);
-        callback(err);
+        // create
+        const opts = Object.assign({}, _this.opts.capped);
+        opts.capped = true;
+        _this.conn.db.createCollection(_this.name, opts, callback);
       }
-    } else {
-      // create
-      const opts = Object.assign({}, _this.opts.capped);
-      opts.capped = true;
-      callback(null);
-    }
+    });
   });
 
-  function callback(err) {
+  function callback(err, collection) {
     if (err) {
       // likely a strict mode error
       _this.conn.emit('error', err);
     } else {
+      _this.collection = collection;
       MongooseCollection.prototype.onOpen.call(_this);
     }
   }

From 8437620fe2b08adaa2d20c0ef10a78e9789cd212 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 11:26:51 -0400
Subject: [PATCH 1077/2348] test: fix tests re: #9244

---
 .../populate/getModelsMapForPopulate.js       | 19 +++++++-------
 test/model.discriminator.querying.test.js     | 26 +++++++------------
 2 files changed, 20 insertions(+), 25 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 9c634fb67c6..c1f082caa07 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -40,6 +40,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
   for (i = 0; i < len; i++) {
     doc = docs[i];
+    let justOne = null;
 
     schema = getSchemaTypes(modelSchema, doc, options.path);
     // Special case: populating a path that's a DocumentArray unless
@@ -76,6 +77,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           isRefPath = isRefPath || res.isRefPath;
           normalizedRefPath = normalizeRefPath(normalizedRefPath, doc, options.path) ||
             res.refPath;
+          justOne = res.justOne;
         } catch (error) {
           return error;
         }
@@ -99,6 +101,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         modelNames = res.modelNames;
         isRefPath = res.isRefPath;
         normalizedRefPath = res.refPath;
+        justOne = res.justOne;
       } catch (error) {
         return error;
       }
@@ -142,7 +145,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     // `justOne = null` means we don't know from the schema whether the end
     // result should be an array or a single doc. This can result from
     // populating a POJO using `Model.populate()`
-    let justOne = null;
     if ('justOne' in options && options.justOne !== void 0) {
       justOne = options.justOne;
     } else if (virtual && virtual.options && virtual.options.refPath) {
@@ -194,12 +196,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     const localFieldGetters = localFieldPath && localFieldPath.getters ? localFieldPath.getters : [];
     let ret;
 
-    if (localFieldPathType != null && schema == null && justOne == null) {
-      justOne = Array.isArray(localFieldPathType) ?
-        localFieldPathType.every(schema => !schema.$isMongooseArray) :
-        !localFieldPathType.$isMongooseArray;
-    }
-
     const _populateOptions = get(options, 'options', {});
 
     const getters = 'getters' in _populateOptions ?
@@ -345,6 +341,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     let modelNames;
     let discriminatorKey;
     let isRefPath = false;
+    let justOne = null;
 
     if (schema && schema.caster) {
       schema = schema.caster;
@@ -413,6 +410,10 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       const _virtualRes = getVirtual(modelForCurrentDoc.schema, options.path);
       const virtual = _virtualRes == null ? null : _virtualRes.virtual;
 
+      if (schemaForCurrentDoc != null) {
+        justOne = !schemaForCurrentDoc.$isMongooseArray && !schemaForCurrentDoc._arrayPath;
+      }
+
       let ref;
       let refPath;
 
@@ -446,14 +447,14 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     }
 
     if (!modelNames) {
-      return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath };
+      return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath, justOne: justOne };
     }
 
     if (!Array.isArray(modelNames)) {
       modelNames = [modelNames];
     }
 
-    return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath };
+    return { modelNames: modelNames, isRefPath: isRefPath, refPath: normalizedRefPath, justOne: justOne };
   }
 };
 
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 1786b57d2a5..c7e981fe39c 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -796,7 +796,7 @@ describe('model', function() {
         });
       });
 
-      it('reference in child schemas (gh-2719-2)', function(done) {
+      it('reference in child schemas (gh-2719-2)', function() {
         function BaseSchema() {
           Schema.apply(this, arguments);
 
@@ -830,29 +830,23 @@ describe('model', function() {
           date: Date
         }));
 
-        Survey.create({
-          name: 'That you see?',
-          date: Date.now()
-        }, function(err, survey) {
-          assert.ifError(err);
+        return co(function*() {
+          const survey = yield Survey.create({
+            name: 'That you see?',
+            date: Date.now()
+          });
 
-          Talk.create({
+          yield Talk.create({
             name: 'Meetup rails',
             date: new Date('2015-04-01T00:00:00Z'),
             pin: '0004',
             period: { start: '11:00', end: '12:00' },
             surveys: [survey]
-          }, function(err) {
-            assert.ifError(err);
-
-            Event.find({}).populate('surveys').exec(function(err, events) {
-              assert.ifError(err);
+          });
 
-              assert.ok(events[0].surveys[0] instanceof Survey);
+          const events = yield Event.find({}).populate('surveys').exec();
 
-              done();
-            });
-          });
+          assert.ok(events[0].surveys[0] instanceof Survey);
         });
       });
     });

From af098984af20358cf0e5d6b9746d44fff32708ba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 11:55:08 -0400
Subject: [PATCH 1078/2348] test(discriminator): repro #9238

---
 test/model.discriminator.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index d6fe821c625..cc1838aa2cc 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1576,4 +1576,20 @@ describe('model', function() {
     const doc = new D({ run: { tab: { id: 42 } } });
     assert.ifError(doc.validateSync());
   });
+
+  it('can use compiled model schema as a discriminator (gh-9238)', function() {
+    const SmsSchema = new mongoose.Schema({ senderNumber: String });
+    const EmailSchema = new mongoose.Schema({ fromEmailAddress: String });
+    const messageSchema = new mongoose.Schema({ method: String }, { discriminatorKey: 'method' });
+
+    const Message = db.model('Test', messageSchema);
+    Message.discriminator('email', EmailSchema);
+    Message.discriminator('sms', SmsSchema);
+
+    const schema = new mongoose.Schema({ actions: [{ name: String }] });
+    const actions = schema.path('actions');
+
+    actions.discriminator('message', Message.schema);
+    assert.ok(actions.schema.discriminators['message']);
+  });
 });

From 933e8741bd8d54c99161f8034fba287a5af40f46 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 11:55:19 -0400
Subject: [PATCH 1079/2348] fix(discriminator): allow passing a compiled
 model's schema as a parameter to `discriminator()`

Fix #9238
---
 lib/helpers/model/discriminator.js | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index b0c446345f8..d62840b7c7e 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -149,11 +149,17 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
 
     for (const _key of keys) {
       if (!CUSTOMIZABLE_DISCRIMINATOR_OPTIONS[_key]) {
+        // Special case: compiling a model sets `pluralization = true` by default. Avoid throwing an error
+        // for that case. See gh-9238
+        if (_key === 'pluralization' && schema.options[_key] == true && baseSchema.options[_key] == null) {
+          continue;
+        }
+
         if (!utils.deepEqual(schema.options[_key], baseSchema.options[_key])) {
           throw new Error('Can\'t customize discriminator option ' + _key +
-          ' (can only modify ' +
-          Object.keys(CUSTOMIZABLE_DISCRIMINATOR_OPTIONS).join(', ') +
-          ')');
+            ' (can only modify ' +
+            Object.keys(CUSTOMIZABLE_DISCRIMINATOR_OPTIONS).join(', ') +
+            ')');
         }
       }
     }

From dee8a7d3b5404f4dde609dcbd95ddfaf5f9b531a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 14:19:53 -0400
Subject: [PATCH 1080/2348] test: fix tests

---
 lib/schema/boolean.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 3c3c7cf187d..eb904ccd34e 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -230,7 +230,7 @@ SchemaBoolean.prototype.castForQuery = function($conditional, val) {
  */
 
 SchemaBoolean.prototype._castNullish = function _castNullish(v) {
-  if (typeof v === 'undefined' && this.$$context._mongooseOptions.omitUndefined) {
+  if (typeof v === 'undefined' && this.$$context != null && this.$$context._mongooseOptions.omitUndefined) {
     return v;
   }
   const castBoolean = typeof this.constructor.cast === 'function' ?

From 333b08976745913ac08714630db50715fdb6d36c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 17 Jul 2020 14:49:53 -0400
Subject: [PATCH 1081/2348] chore: release 5.9.25

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index ba0f2e90f44..c86789befba 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.9.25 / 2020-07-17
+===================
+ * fix(discriminator): allow passing a compiled model's schema as a parameter to `discriminator()` #9238
+ * fix(connection): throw more readable error when querying db before initial connection when `bufferCommands = false` #9239
+ * fix(indexes): don't unnecessarily drop text indexes when running `syncIndexes()` #9225
+ * fix: make Boolean _castNullish respect omitUndefined #9242 [ehpc](https://github.com/ehpc)
+ * fix(populate): populate single nested discriminator underneath doc array when populated docs have different model but same id #9244
+ * docs(mongoose): correct formatting typo #9247 [JNa0](https://github.com/JNa0)
+
 5.9.24 / 2020-07-13
 ===================
  * fix(connection): respect connection-level `bufferCommands` option if `mongoose.connect()` is called after `mongoose.model()` #9179
diff --git a/package.json b/package.json
index da742beb505..d25ea97ac89 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.24",
+  "version": "5.9.25",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 6e4ab98bbf0d7c5b3d5e8c86da15bf3df2ce8305 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 19 Jul 2020 13:39:15 -0400
Subject: [PATCH 1082/2348] docs(connections): clarify that Mongoose can emit
 'connected' when reconnecting after losing connectivity

Fix #9240
---
 docs/connections.pug | 7 ++++++-
 lib/schematype.js    | 1 -
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index a76fa43dac4..3767b62f7ea 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -273,7 +273,7 @@ block content
     connection may emit.
 
     * `connecting`: Emitted when Mongoose starts making its initial connection to the MongoDB server
-    * `connected`: Emitted when Mongoose successfully makes its initial connection to the MongoDB server
+    * `connected`: Emitted when Mongoose successfully makes its initial connection to the MongoDB server, or when Mongoose reconnects after losing connectivity.
     * `open`: Equivalent to `connected`
     * `disconnecting`: Your app called [`Connection#close()`](api.html#connection_Connection-close) to disconnect from MongoDB
     * `disconnected`: Emitted when Mongoose lost connection to the MongoDB server. This event may be due to your code explicitly closing the connection, the database server crashing, or network connectivity issues.
@@ -284,6 +284,11 @@ block content
     * `all`: Emitted when you're connecting to a replica set and Mongoose has successfully connected to all servers specified in your connection string.
     * `reconnectFailed`: Emitted when you're connected to a standalone server and Mongoose has run out of [`reconnectTries`](https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html#handling-single-server-outages). The [MongoDB driver](http://npmjs.com/package/mongodb) will no longer attempt to reconnect after this event is emitted. This event will never be emitted if you're connected to a replica set.
 
+    When you're connecting to a single MongoDB server (a "standalone"), Mongoose will emit 'disconnected' if it gets
+    disconnected from the standalone server, and 'connected' if it successfully connects to the standalone. In a
+    replica set with `useUnifiedTopology = true`, Mongoose will emit 'disconnected' if it loses connectivity to
+    _every_ server in the replica set, and 'connected' if it manages to reconnect to at least one server in the replica set.
+
     <h3 id="keepAlive"><a href="#keepAlive">A note about keepAlive</a></h3>
 
     For long running applications, it is often prudent to enable `keepAlive`
diff --git a/lib/schematype.js b/lib/schematype.js
index 08f48356a9a..938a376c48b 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -54,7 +54,6 @@ function SchemaType(path, options, instance) {
     }
   }
 
-
   if (options.select == null) {
     delete options.select;
   }

From 402de9cad8e0bc3dae846146e22bc61d9f9bd8bc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 19 Jul 2020 14:18:32 -0400
Subject: [PATCH 1083/2348] refactor: set `returnOriginal` instead of `new`
 with global `returnOriginal` option

---
 lib/query.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index eb81328612e..4bca9b90623 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3017,8 +3017,8 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
 
 
   const returnOriginal = get(this, 'model.base.options.returnOriginal');
-  if (options.new == null && returnOriginal != null) {
-    options.new = !returnOriginal;
+  if (options.returnOriginal == null && returnOriginal != null) {
+    options.returnOriginal = returnOriginal;
   }
 
   this.setOptions(options);
@@ -3343,8 +3343,8 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
   options = options || {};
 
   const returnOriginal = get(this, 'model.base.options.returnOriginal');
-  if (options.new == null && returnOriginal != null) {
-    options.new = !returnOriginal;
+  if (options.returnOriginal == null && returnOriginal != null) {
+    options.returnOriginal = returnOriginal;
   }
 
   this.setOptions(options);

From 04f9a7a5394dfa61b0f3d416fd44df4fc332f322 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 19 Jul 2020 14:23:38 -0400
Subject: [PATCH 1084/2348] docs(returnOriginal): clarify that `returnOriginal`
 doesn't set `new`, and link to `findOneAndUpdate()` tutorial

---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index 324f5af9d63..6a3e5ea2674 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -147,7 +147,7 @@ Mongoose.prototype.driver = require('./driver');
  *
  * Currently supported options are:
  * - 'debug': If `true`, prints the operations mongoose sends to MongoDB to the console. If a writable stream is passed, it will log to that stream, without colorization. If a callback function is passed, it will receive the collection name, the method name, then all arugments passed to the method. For example, if you wanted to replicate the default logging, you could output from the callback `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
- * - 'returnOriginal': If `false`, changes the default `new` option to `findOneAndUpdate()`, `findByIdAndUpdate` and `findOneAndReplace()` to true.
+ * - 'returnOriginal': If `false`, changes the default `returnOriginal` option to `findOneAndUpdate()`, `findByIdAndUpdate`, and `findOneAndReplace()` to false. This is equivalent to setting the `new` option to `true` for `findOneAndX()` calls by default. Read our [`findOneAndUpdate()` tutorial](/docs/tutorials/findoneandupdate.html) for more information.
  * - 'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models
  * - 'useCreateIndex': false by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
  * - 'useFindAndModify': true by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.

From 74aab53a9077c2c935e43c6dc7d625a5fee3bd58 Mon Sep 17 00:00:00 2001
From: Vivek Shah <shahvicky1992@gmail.com>
Date: Tue, 21 Jul 2020 15:50:24 -0700
Subject: [PATCH 1085/2348] chore: remove extra poolSize option in comment

---
 lib/connection.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 0123c00bf5c..a2618c8c974 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -552,7 +552,6 @@ Connection.prototype.onOpen = function() {
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
  * @param {Class} [options.promiseLibrary] Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
- * @param {Number} [options.poolSize=5] The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
  * @param {Number} [options.bufferMaxEntries] This option does nothing if `useUnifiedTopology` is set. The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.

From 0b884ea85da938fbb9d7c6b776a71e5f588a2b8f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 23 Jul 2020 16:32:03 -0400
Subject: [PATCH 1086/2348] test(timestamps): repro #9268

---
 test/timestamps.test.js | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index dedb2dccb19..c916c2ebc45 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -364,4 +364,35 @@ describe('timestamps', function() {
         assert.ok(doc.products[0].lastJournal.updatedAt);
       });
   });
+
+  it('sets timestamps on bulk write without `$set` (gh-9268)', function() {
+    const NestedSchema = new Schema({ name: String }, {
+      timestamps: true,
+      _id: false
+    });
+    const TestSchema = new Schema({
+      nestedDoc: NestedSchema
+    });
+    const Test = db.model('Test', TestSchema);
+
+    return co(function*() {
+      yield Test.create({ nestedDoc: { name: 'test' } });
+      const doc = yield Test.findOne().lean();
+
+      yield cb => setTimeout(cb, 10);
+      yield Test.bulkWrite([
+        {
+          updateOne: {
+            filter: {},
+            update: {
+              'nestedDoc.name': 'test2'
+            }
+          }
+        }
+      ]);
+
+      const newDoc = yield Test.findById(doc).lean();
+      assert.ok(newDoc.nestedDoc.updatedAt > doc.nestedDoc.updatedAt);
+    });
+  });
 });

From a683c7275f44d0e4e846637be034dad1f78e7c7a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 23 Jul 2020 16:41:34 -0400
Subject: [PATCH 1087/2348] fix(timestamps): apply timestamps to `bulkWrite()`
 updates when not using `$set`

Fix #9268
---
 lib/helpers/model/castBulkWrite.js            |   1 -
 .../update/applyTimestampsToChildren.js       | 169 ++++++++----------
 2 files changed, 76 insertions(+), 94 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 26b7c7f7560..0455562f461 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -54,7 +54,6 @@ module.exports = function castBulkWrite(originalModel, op, options) {
 
         applyTimestampsToChildren(now, op['updateOne']['update'], model.schema);
 
-
         if (op['updateOne'].setDefaultsOnInsert) {
           setDefaultsOnInsert(op['updateOne']['filter'], model.schema, op['updateOne']['update'], {
             setDefaultsOnInsert: true,
diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 7e9edd881eb..55b8d1f3161 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -15,25 +15,19 @@ function applyTimestampsToChildren(now, update, schema) {
   }
 
   const keys = Object.keys(update);
-  let key;
-  let createdAt;
-  let updatedAt;
-  let timestamps;
-  let path;
-
   const hasDollarKey = keys.length && keys[0].startsWith('$');
 
   if (hasDollarKey) {
     if (update.$push) {
-      for (key in update.$push) {
+      for (const key of Object.keys(update.$push)) {
         const $path = schema.path(key);
         if (update.$push[key] &&
             $path &&
             $path.$isMongooseDocumentArray &&
             $path.schema.options.timestamps) {
-          timestamps = $path.schema.options.timestamps;
-          createdAt = handleTimestampOption(timestamps, 'createdAt');
-          updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+          const timestamps = $path.schema.options.timestamps;
+          const createdAt = handleTimestampOption(timestamps, 'createdAt');
+          const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
           if (update.$push[key].$each) {
             update.$push[key].$each.forEach(function(subdoc) {
               if (updatedAt != null) {
@@ -56,93 +50,14 @@ function applyTimestampsToChildren(now, update, schema) {
     }
     if (update.$set != null) {
       const keys = Object.keys(update.$set);
-      for (key of keys) {
-        // Replace positional operator `$` and array filters `$[]` and `$[.*]`
-        const keyToSearch = cleanPositionalOperators(key);
-        path = schema.path(keyToSearch);
-        if (!path) {
-          continue;
-        }
-
-        const parentSchemaTypes = [];
-        const pieces = keyToSearch.split('.');
-        for (let i = pieces.length - 1; i > 0; --i) {
-          const s = schema.path(pieces.slice(0, i).join('.'));
-          if (s != null &&
-            (s.$isMongooseDocumentArray || s.$isSingleNested)) {
-            parentSchemaTypes.push({ parentPath: key.split('.').slice(0, i).join('.'), parentSchemaType: s });
-          }
-        }
-
-        if (Array.isArray(update.$set[key]) && path.$isMongooseDocumentArray) {
-          applyTimestampsToDocumentArray(update.$set[key], path, now);
-        } else if (update.$set[key] && path.$isSingleNested) {
-          applyTimestampsToSingleNested(update.$set[key], path, now);
-        } else if (parentSchemaTypes.length > 0) {
-          for (const item of parentSchemaTypes) {
-            const parentPath = item.parentPath;
-            const parentSchemaType = item.parentSchemaType;
-            timestamps = parentSchemaType.schema.options.timestamps;
-            createdAt = handleTimestampOption(timestamps, 'createdAt');
-            updatedAt = handleTimestampOption(timestamps, 'updatedAt');
-
-            if (!timestamps || updatedAt == null) {
-              continue;
-            }
-
-            if (parentSchemaType.$isSingleNested) {
-              // Single nested is easy
-              update.$set[parentPath + '.' + updatedAt] = now;
-              continue;
-            }
-
-            if (parentSchemaType.$isMongooseDocumentArray) {
-              let childPath = key.substr(parentPath.length + 1);
-
-              if (/^\d+$/.test(childPath)) {
-                update.$set[parentPath + '.' + childPath][updatedAt] = now;
-                continue;
-              }
-
-              const firstDot = childPath.indexOf('.');
-              childPath = firstDot !== -1 ? childPath.substr(0, firstDot) : childPath;
-
-              update.$set[parentPath + '.' + childPath + '.' + updatedAt] = now;
-            }
-          }
-        } else if (path.schema != null && path.schema != schema && update.$set[key]) {
-          timestamps = path.schema.options.timestamps;
-          createdAt = handleTimestampOption(timestamps, 'createdAt');
-          updatedAt = handleTimestampOption(timestamps, 'updatedAt');
-
-          if (!timestamps) {
-            continue;
-          }
-
-          if (updatedAt != null) {
-            update.$set[key][updatedAt] = now;
-          }
-          if (createdAt != null) {
-            update.$set[key][createdAt] = now;
-          }
-        }
+      for (const key of keys) {
+        applyTimestampsToUpdateKey(schema, key, update.$set, now);
       }
     }
   } else {
     const keys = Object.keys(update).filter(key => !key.startsWith('$'));
-    for (key of keys) {
-      // Replace positional operator `$` and array filters `$[]` and `$[.*]`
-      const keyToSearch = cleanPositionalOperators(key);
-      path = schema.path(keyToSearch);
-      if (!path) {
-        continue;
-      }
-
-      if (Array.isArray(update[key]) && path.$isMongooseDocumentArray) {
-        applyTimestampsToDocumentArray(update[key], path, now);
-      } else if (update[key] != null && path.$isSingleNested) {
-        applyTimestampsToSingleNested(update[key], path, now);
-      }
+    for (const key of keys) {
+      applyTimestampsToUpdateKey(schema, key, update, now);
     }
   }
 }
@@ -187,3 +102,71 @@ function applyTimestampsToSingleNested(subdoc, schematype, now) {
 
   applyTimestampsToChildren(now, subdoc, schematype.schema);
 }
+
+function applyTimestampsToUpdateKey(schema, key, update, now) {
+  // Replace positional operator `$` and array filters `$[]` and `$[.*]`
+  const keyToSearch = cleanPositionalOperators(key);
+  const path = schema.path(keyToSearch);
+  if (!path) {
+    return;
+  }
+
+  const parentSchemaTypes = [];
+  const pieces = keyToSearch.split('.');
+  for (let i = pieces.length - 1; i > 0; --i) {
+    const s = schema.path(pieces.slice(0, i).join('.'));
+    if (s != null &&
+      (s.$isMongooseDocumentArray || s.$isSingleNested)) {
+      parentSchemaTypes.push({ parentPath: key.split('.').slice(0, i).join('.'), parentSchemaType: s });
+    }
+  }
+
+  if (Array.isArray(update[key]) && path.$isMongooseDocumentArray) {
+    applyTimestampsToDocumentArray(update[key], path, now);
+  } else if (update[key] && path.$isSingleNested) {
+    applyTimestampsToSingleNested(update[key], path, now);
+  } else if (parentSchemaTypes.length > 0) {
+    for (const item of parentSchemaTypes) {
+      const parentPath = item.parentPath;
+      const parentSchemaType = item.parentSchemaType;
+      const timestamps = parentSchemaType.schema.options.timestamps;
+      const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+
+      if (!timestamps || updatedAt == null) {
+        continue;
+      }
+
+      if (parentSchemaType.$isSingleNested) {
+        // Single nested is easy
+        update[parentPath + '.' + updatedAt] = now;
+      } else if (parentSchemaType.$isMongooseDocumentArray) {
+        let childPath = key.substr(parentPath.length + 1);
+
+        if (/^\d+$/.test(childPath)) {
+          update[parentPath + '.' + childPath][updatedAt] = now;
+          continue;
+        }
+
+        const firstDot = childPath.indexOf('.');
+        childPath = firstDot !== -1 ? childPath.substr(0, firstDot) : childPath;
+
+        update[parentPath + '.' + childPath + '.' + updatedAt] = now;
+      }
+    }
+  } else if (path.schema != null && path.schema != schema && update[key]) {
+    const timestamps = path.schema.options.timestamps;
+    const createdAt = handleTimestampOption(timestamps, 'createdAt');
+    const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+
+    if (!timestamps) {
+      return;
+    }
+
+    if (updatedAt != null) {
+      update[key][updatedAt] = now;
+    }
+    if (createdAt != null) {
+      update[key][createdAt] = now;
+    }
+  }
+}
\ No newline at end of file

From 13559acc7cd4b3c64eed80bed74baddeeba66f23 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 23 Jul 2020 16:48:57 -0400
Subject: [PATCH 1088/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index ac945e00a72..d5a8451dd17 100644
--- a/index.pug
+++ b/index.pug
@@ -361,6 +361,9 @@ html(lang='en')
               <a href="https://www.parhaatkasinot.com/">
                 <img class="sponsor" src="https://images.opencollective.com/parhaatkasinot/e7fda21/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.polskiekasyno.com/">
+                <img class="sponsor" src="https://images.opencollective.com/polskiekasyno-com/a8975c6/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 0ec05c1885969a4ce069e54c3c888aa78fc5964c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 24 Jul 2020 11:25:05 -0400
Subject: [PATCH 1089/2348] docs(document+model): clarify how
 `validateModifiedOnly` option works

Fix #9263
---
 lib/document.js | 4 ++--
 lib/model.js    | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 5336b8f723e..fc4118ae3b9 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2456,7 +2456,7 @@ function _handlePathsToValidate(paths, pathsToValidate) {
  *
  * @param {Array|string} pathsToValidate only validate the given paths
  * @param {Object} [options] options for validation
- * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
+ * @param {Boolean} [options.validateModifiedOnly=false] If `true`, Mongoose will only validate modified paths, as opposed to modified paths and `required` paths.
  * @return {ValidationError|undefined} ValidationError if there are errors during validation, or undefined if there is no error.
  * @api public
  */
@@ -2658,7 +2658,7 @@ function _markValidSubpaths(doc, path) {
  * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this save operation. If not specified, defaults to the [document's associated session](api.html#document_Document-$session).
  * @param {Object} [options.safe] (DEPRECATED) overrides [schema's safe option](http://mongoosejs.com//docs/guide.html#safe). Use the `w` option instead.
  * @param {Boolean} [options.validateBeforeSave] set to false to save without validating.
- * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
+ * @param {Boolean} [options.validateModifiedOnly=false] If `true`, Mongoose will only validate modified paths, as opposed to modified paths and `required` paths.
  * @param {Number|String} [options.w] set the [write concern](https://docs.mongodb.com/manual/reference/write-concern/#w-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Boolean} [options.j] set to true for MongoDB to wait until this `save()` has been [journaled before resolving the returned promise](https://docs.mongodb.com/manual/reference/write-concern/#j-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Number} [options.wtimeout] sets a [timeout for the write concern](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern).
diff --git a/lib/model.js b/lib/model.js
index a0c1b71f3ef..edf070cf74d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -436,7 +436,7 @@ function generateVersionError(doc, modifiedPaths) {
  * @param {Session} [options.session=null] the [session](https://docs.mongodb.com/manual/reference/server-sessions/) associated with this save operation. If not specified, defaults to the [document's associated session](api.html#document_Document-$session).
  * @param {Object} [options.safe] (DEPRECATED) overrides [schema's safe option](http://mongoosejs.com//docs/guide.html#safe). Use the `w` option instead.
  * @param {Boolean} [options.validateBeforeSave] set to false to save without validating.
- * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
+ * @param {Boolean} [options.validateModifiedOnly=false] if `true`, Mongoose will only validate modified paths, as opposed to modified paths and `required` paths.
  * @param {Number|String} [options.w] set the [write concern](https://docs.mongodb.com/manual/reference/write-concern/#w-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Boolean} [options.j] set to true for MongoDB to wait until this `save()` has been [journaled before resolving the returned promise](https://docs.mongodb.com/manual/reference/write-concern/#j-option). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern)
  * @param {Number} [options.wtimeout] sets a [timeout for the write concern](https://docs.mongodb.com/manual/reference/write-concern/#wtimeout). Overrides the [schema-level `writeConcern` option](/docs/guide.html#writeConcern).

From 34017b5b768411c64f1ca7b784012fdc37958c45 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 24 Jul 2020 11:55:07 -0400
Subject: [PATCH 1090/2348] fix: make subdocument's `invalidate()` methods have
 the same return value as top-level document

Fix #9271
---
 lib/types/embedded.js    | 4 ++--
 lib/types/subdocument.js | 2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 4296d6c7ac7..96990befa2d 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -280,7 +280,7 @@ EmbeddedDocument.prototype.invalidate = function(path, err, val) {
 
   if (!this[documentArrayParent] || this.__index == null) {
     if (err[validatorErrorSymbol] || err instanceof ValidationError) {
-      return true;
+      return this.ownerDocument().$__.validationError
     }
     throw err;
   }
@@ -290,7 +290,7 @@ EmbeddedDocument.prototype.invalidate = function(path, err, val) {
   const fullPath = [parentPath, index, path].join('.');
   this[documentArrayParent].invalidate(fullPath, err, val);
 
-  return true;
+  return this.ownerDocument().$__.validationError;
 };
 
 /**
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index b015a091cf3..4142d82ced1 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -170,6 +170,8 @@ Subdocument.prototype.invalidate = function(path, err, val) {
   } else if (err.kind === 'cast' || err.name === 'CastError') {
     throw err;
   }
+
+  return this.ownerDocument().$__.validationError;
 };
 
 /*!

From 4ae4a9be43077b979120980d08e5c4eb7e42815a Mon Sep 17 00:00:00 2001
From: Vivek Shah <shahvicky1992@gmail.com>
Date: Fri, 24 Jul 2020 14:31:04 -0700
Subject: [PATCH 1091/2348] docs: point bulkWrite() link to mongoose docs

---
 docs/migrating_to_5.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/migrating_to_5.pug b/docs/migrating_to_5.pug
index f2f46790ded..04729953669 100644
--- a/docs/migrating_to_5.pug
+++ b/docs/migrating_to_5.pug
@@ -489,7 +489,7 @@ block content
     </a></h3>
 
     Mongoose 5.x uses version 3.x of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb). MongoDB driver 3.x changed the format of
-    the result of [`bulkWrite()` calls](http://localhost:8088/docs/api.html#model_Model.bulkWrite) so there is no longer a top-level `nInserted`, `nModified`, etc. property. The new result object structure is [described here](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult).
+    the result of [`bulkWrite()` calls](http://mongoosejs.com//docs/api.html#model_Model.bulkWrite) so there is no longer a top-level `nInserted`, `nModified`, etc. property. The new result object structure is [described here](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult).
 
     ```javascript
     const Model = mongoose.model('Test', new Schema({ name: String }));

From 3eeccad375fbe85ad1a1031ee3e395fcb83dba02 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jul 2020 14:17:47 -0400
Subject: [PATCH 1092/2348] test(document): repro #9281

---
 test/document.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 01dc74ae3f3..e13362b7bcc 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9081,4 +9081,31 @@ describe('document', function() {
       assert.strictEqual(doc.nested.myBool, true);
     });
   });
+
+  it('handles immutable properties underneath single nested subdocs when overwriting (gh-9281)', function() {
+    const SubSchema = Schema({
+      nestedProp: {
+        type: String,
+        immutable: true
+      }
+    }, { strict: 'throw' });
+
+    const TestSchema = Schema({ object: SubSchema }, { strict: 'throw' });
+    const Test = db.model('Test', TestSchema);
+
+    return co(function*() {
+      yield Test.create({ object: { nestedProp: 'A' } });
+      const doc = yield Test.findOne();
+
+      doc.object = {};
+      const err = yield doc.save().then(() => null, err => err);
+
+      assert.ok(err);
+      assert.ok(err.errors['object']);
+      assert.ok(err.message.includes('Path `nestedProp` is immutable'), err.message);
+
+      doc.object = { nestedProp: 'A' };
+      yield doc.save();
+    });
+  });
 });

From 66f1fd9887b00b975781ebcb886d112ebba71736 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jul 2020 14:18:52 -0400
Subject: [PATCH 1093/2348] fix(document): throw error when overwriting a
 single nested subdoc changes an immutable path within the subdoc

Fix #9281
---
 lib/document.js                           | 27 +++++++++++++++++++++++
 lib/helpers/schematype/handleImmutable.js |  6 +++--
 lib/schema/SingleNestedPath.js            |  2 +-
 lib/types/embedded.js                     |  2 +-
 4 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index fc4118ae3b9..0c5946c97db 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1239,6 +1239,10 @@ Document.prototype.$set = function $set(path, val, type, options) {
       delete this.$__.populated[path];
     }
 
+    if (schema.$isSingleNested && val != null) {
+      _checkImmutableSubpaths(val, schema, priorVal);
+    }
+
     this.$markValid(path);
   } catch (e) {
     if (e instanceof MongooseError.StrictModeError && e.isImmutableError) {
@@ -2637,6 +2641,29 @@ function _markValidSubpaths(doc, path) {
   }
 }
 
+/*!
+ * ignore
+ */
+
+function _checkImmutableSubpaths(subdoc, schematype, priorVal) {
+  const schema = schematype.schema;
+  if (schema == null) {
+    return;
+  }
+
+  for (const key of Object.keys(schema.paths)) {
+    const path = schema.paths[key];
+    if (path.$immutableSetter == null) {
+      continue;
+    }
+    const oldVal = priorVal == null ? void 0 : priorVal.$__getValue(key);
+    // Calling immutableSetter with `oldVal` even though it expects `newVal`
+    // is intentional. That's because `$immutableSetter` compares its param
+    // to the current value.
+    path.$immutableSetter.call(subdoc, oldVal);
+  }
+}
+
 /**
  * Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`,
  * or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation **only** with the modifications to the database, it does not replace the whole document in the latter case.
diff --git a/lib/helpers/schematype/handleImmutable.js b/lib/helpers/schematype/handleImmutable.js
index 14f647a32bb..e31c4af2861 100644
--- a/lib/helpers/schematype/handleImmutable.js
+++ b/lib/helpers/schematype/handleImmutable.js
@@ -33,11 +33,13 @@ function createImmutableSetter(path, immutable) {
     if (!_immutable) {
       return v;
     }
-    if (this.$__.strictMode === 'throw' && v !== this[path]) {
+
+    const _value = this.$__getValue(path);
+    if (this.$__.strictMode === 'throw' && v !== _value) {
       throw new StrictModeError(path, 'Path `' + path + '` is immutable ' +
         'and strict mode is set to throw.', true);
     }
 
-    return this[path];
+    return _value;
   };
 }
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index a23b7d960a4..f05b7d272a1 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -175,7 +175,7 @@ SingleNestedPath.prototype.cast = function(val, doc, init, priorVal) {
     subdoc.init(val);
   } else {
     if (Object.keys(val).length === 0) {
-      return new Constructor({}, selected, doc);
+      return new Constructor({}, selected, doc, undefined, { priorDoc: priorVal });
     }
 
     return new Constructor(val, selected, doc, undefined, { priorDoc: priorVal });
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 96990befa2d..9c1e1daad2e 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -280,7 +280,7 @@ EmbeddedDocument.prototype.invalidate = function(path, err, val) {
 
   if (!this[documentArrayParent] || this.__index == null) {
     if (err[validatorErrorSymbol] || err instanceof ValidationError) {
-      return this.ownerDocument().$__.validationError
+      return this.ownerDocument().$__.validationError;
     }
     throw err;
   }

From 1a4146c463a9fd58198976f4807d77e2f511d167 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 25 Jul 2020 14:57:05 -0400
Subject: [PATCH 1094/2348] test: fix tests on 5.10 for #9208

---
 lib/types/subdocument.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 1925e6c3528..61b53f0e45e 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -53,6 +53,7 @@ function Subdocument(value, fields, parent, skipId, options) {
     }
 
     delete options.priorDoc;
+    delete this.$__.$options.priorDoc;
   }
 }
 

From ffdfe887abe213fd15ecce102016cb91db675c78 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jul 2020 17:27:30 -0400
Subject: [PATCH 1095/2348] docs(model): make `create()` docs use async/await,
 and add another warning about how `create()` with options requires array
 syntax

Fix #9280
---
 lib/model.js | 30 ++++++++++--------------------
 1 file changed, 10 insertions(+), 20 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index edf070cf74d..0f95ca1ef60 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2948,26 +2948,16 @@ Model.findByIdAndRemove = function(id, options, callback) {
  *
  * ####Example:
  *
- *     // pass a spread of docs and a callback
- *     Candy.create({ type: 'jelly bean' }, { type: 'snickers' }, function (err, jellybean, snickers) {
- *       if (err) // ...
- *     });
- *
- *     // pass an array of docs
- *     var array = [{ type: 'jelly bean' }, { type: 'snickers' }];
- *     Candy.create(array, function (err, candies) {
- *       if (err) // ...
- *
- *       var jellybean = candies[0];
- *       var snickers = candies[1];
- *       // ...
- *     });
- *
- *     // callback is optional; use the returned promise if you like:
- *     var promise = Candy.create({ type: 'jawbreaker' });
- *     promise.then(function (jawbreaker) {
- *       // ...
- *     })
+ *     // Insert one new `Character` document
+ *     await Character.create({ name: 'Jean-Luc Picard' });
+ * 
+ *     // Insert multiple new `Character` documents
+ *     await Character.create([{ name: 'Will Riker' }, { name: 'Geordi LaForge' }]);
+ * 
+ *     // Create a new character within a transaction. Note that you **must**
+ *     // pass an array as the first parameter to `create()` if you want to
+ *     // specify options.
+ *     await Character.create([{ name: 'Jean-Luc Picard' }], { session });
  *
  * @param {Array|Object} docs Documents to insert, as a spread or array
  * @param {Object} [options] Options passed down to `save()`. To specify `options`, `docs` **must** be an array, not a spread.

From c6188a7c925439d29645abf5c1c8bed0613ddffa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Jul 2020 17:41:31 -0400
Subject: [PATCH 1096/2348] docs(populate): clarify that you can't filter based
 on foreign document properties when populating

Fix #9279
---
 docs/populate.pug | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index a2a5cdf0497..a55f35dbeb2 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -256,7 +256,7 @@ block content
 
     ```javascript
     Story.
-      find(...).
+      find().
       populate({
         path: 'fans',
         match: { age: { $gte: 21 } },
@@ -266,6 +266,33 @@ block content
       exec();
     ```
 
+    The `match` option doesn't filter out `Story` documents. If there are no documents that satisfy `match`,
+    you'll get a `Story` document with an empty `fans` array.
+
+    For example, suppose you `populate()` a story's `author` and the `author` doesn't satisfy `match`. Then
+    the story's `author` will be `null`.
+
+    ```javascript
+    const story = await Story.
+      findOne({ title: 'Casino Royale' }).
+      populate({ path: 'author', name: { $ne: 'Ian Fleming' } }).
+      exec();
+    story.author; // `null`
+    ```
+
+    In general, there is no way to make `populate()` filter stories based on properties of the story's `author`.
+    For example, the below query won't return any results, even though `author` is populated.
+
+    ```javascript
+    const story = await Story.
+      findOne({ 'author.name': 'Ian Fleming' }).
+      populate('author').
+      exec();
+    story; // null
+    ```
+
+    If you want to filter stories by their author's name, you should use [denormalization](https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-3).
+
     <h3 id="limit-vs-perDocumentLimit"><a href="#limit-vs-perDocumentLimit">limit vs. perDocumentLimit</a></h3>
 
     Populate does support a `limit` option, however, it currently

From 6a7b2755e253afc7e7f2d1c540287be5e3ec3a28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 13:41:08 -0400
Subject: [PATCH 1097/2348] feat(schema+model): add `optimisticConcurrency`
 option to use OCC for `save()`

Fix #9001 #5424
---
 docs/guide.pug          | 72 +++++++++++++++++++++++++++++++++++++++--
 lib/model.js            |  9 ++++--
 lib/schema.js           |  7 +++-
 test/versioning.test.js | 22 +++++++++++++
 4 files changed, 104 insertions(+), 6 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index c4f501f4cdd..39c021d6682 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -434,6 +434,7 @@ block content
     - [useNestedStrict](#useNestedStrict)
     - [validateBeforeSave](#validateBeforeSave)
     - [versionKey](#versionKey)
+    - [optimisticConcurrency](#optimisticConcurrency)
     - [collation](#collation)
     - [selectPopulatedPaths](#selectPopulatedPaths)
     - [skipVersioning](#skipVersioning)
@@ -891,9 +892,8 @@ block content
     thing.save(); // { _somethingElse: 0, name: 'mongoose v3' }
     ```
 
-    Note that Mongoose versioning is **not** a full [optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control)
-    solution. Use [mongoose-update-if-current](https://github.com/eoin-obrien/mongoose-update-if-current)
-    for OCC support. Mongoose versioning only operates on arrays:
+    Note that Mongoose's default versioning is **not** a full [optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control)
+    solution. Mongoose's default versioning only operates on arrays as shown below.
 
     ```javascript
     // 2 copies of the same document
@@ -911,6 +911,8 @@ block content
     await doc2.save();
     ```
 
+    If you need optimistic concurrency support for `save()`, you can set the [`optimisticConcurrency` option](#optimisticConcurrency)
+
     Document versioning can also be disabled by setting the `versionKey` to
     `false`.
     _DO NOT disable versioning unless you [know what you are doing](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)._
@@ -946,6 +948,70 @@ block content
     });
     ```
 
+    <h3 id="optimisticConcurrency"><a href="#optimisticConcurrency">option: optimisticConcurrency</a></h3>
+
+    [Optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control) is a strategy to ensure
+    the document you're updating didn't change between when you loaded it using `find()` or `findOne()`, and when
+    you update it using `save()`.
+
+    For example, suppose you have a `House` model that contains a list of `photos`, and a `status` that represents
+    whether this house shows up in searches. Suppose that a house that has status `'APPROVED'` must have at least
+    two `photos`. You might implement the logic of approving a house document as shown below:
+
+    ```javascript
+    async function markApproved(id) {
+      const house = await House.findOne({ _id });
+      if (house.photos.length < 2) {
+        throw new Error('House must have at least two photos!');
+      }
+      
+      house.status = 'APPROVED';
+      await house.save();
+    }
+    ```
+
+    The `markApproved()` function looks right in isolation, but there might be a potential issue: what if another
+    function removes the house's photos between the `findOne()` call and the `save()` call? For example, the below
+    code will succeed:
+
+    ```javascript
+    const house = await House.findOne({ _id });
+    if (house.photos.length < 2) {
+      throw new Error('House must have at least two photos!');
+    }
+
+    const house2 = await House.findOne({ _id });
+    house2.photos = [];
+    await house2.save();
+
+    // Marks the house as 'APPROVED' even though it has 0 photos!
+    house.status = 'APPROVED';
+    await house.save();
+    ```
+
+    If you set the `optimisticConcurrency` option on the `House` model's schema, the above script will throw an
+    error.
+
+    ```javascript
+    const House = mongoose.model('House', Schema({
+      status: String,
+      photos: [String]
+    }, { optimisticConcurrency: true }));
+
+    const house = await House.findOne({ _id });
+    if (house.photos.length < 2) {
+      throw new Error('House must have at least two photos!');
+    }
+
+    const house2 = await House.findOne({ _id });
+    house2.photos = [];
+    await house2.save();
+
+    // Throws 'VersionError: No matching document found for id "..." version 0'
+    house.status = 'APPROVED';
+    await house.save();
+    ```
+
     <h3 id="collation"><a href="#collation">option: collation</a></h3>
 
     Sets a default [collation](https://docs.mongodb.com/manual/reference/collation/)
diff --git a/lib/model.js b/lib/model.js
index b6633d7ad80..da175b20e38 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -542,6 +542,11 @@ function operand(self, where, delta, data, val, op) {
   // already marked for versioning?
   if (VERSION_ALL === (VERSION_ALL & self.$__.version)) return;
 
+  if (self.schema.options.optimisticConcurrency) {
+    self.$__.version = VERSION_ALL;
+    return;
+  }
+
   switch (op) {
     case '$set':
     case '$unset':
@@ -2950,10 +2955,10 @@ Model.findByIdAndRemove = function(id, options, callback) {
  *
  *     // Insert one new `Character` document
  *     await Character.create({ name: 'Jean-Luc Picard' });
- * 
+ *
  *     // Insert multiple new `Character` documents
  *     await Character.create([{ name: 'Will Riker' }, { name: 'Geordi LaForge' }]);
- * 
+ *
  *     // Create a new character within a transaction. Note that you **must**
  *     // pass an array as the first parameter to `create()` if you want to
  *     // specify options.
diff --git a/lib/schema.js b/lib/schema.js
index c64e829b848..b7099cb8bac 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -69,7 +69,7 @@ let id = 0;
  * - [typePojoToMixed](/docs/guide.html#typePojoToMixed) - boolean - defaults to true. Determines whether a type set to a POJO becomes a Mixed path or a Subdocument
  * - [useNestedStrict](/docs/guide.html#useNestedStrict) - boolean - defaults to false
  * - [validateBeforeSave](/docs/guide.html#validateBeforeSave) - bool - defaults to `true`
- * - [versionKey](/docs/guide.html#versionKey): string - defaults to "__v"
+ * - [versionKey](/docs/guide.html#versionKey): string or object - defaults to "__v"
  * - [collation](/docs/guide.html#collation): object - defaults to null (which means use no collation)
  * - [selectPopulatedPaths](/docs/guide.html#selectPopulatedPaths): boolean - defaults to `true`
  * - [skipVersioning](/docs/guide.html#skipVersioning): object - paths to exclude from versioning
@@ -404,6 +404,7 @@ Schema.prototype.defaultOptions = function(options) {
     bufferCommands: true,
     capped: false, // { size, max, autoIndexId }
     versionKey: '__v',
+    optimisticConcurrency: false,
     discriminatorKey: '__t',
     minimize: true,
     autoIndex: null,
@@ -423,6 +424,10 @@ Schema.prototype.defaultOptions = function(options) {
     options.read = readPref(options.read);
   }
 
+  if (options.optimisticConcurrency && !options.versionKey) {
+    throw new MongooseError('Must set `versionKey` if using `optimisticConcurrency`');
+  }
+
   return options;
 };
 
diff --git a/test/versioning.test.js b/test/versioning.test.js
index ec3cd6ea64d..538e49c177c 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -593,4 +593,26 @@ describe('versioning', function() {
       }).
       catch(done);
   });
+
+  it('optimistic concurrency (gh-9001) (gh-5424)', function() {
+    const schema = new Schema({ name: String }, { optimisticConcurrency: true });
+    const M = db.model('Test', schema);
+
+    const doc = new M({ name: 'foo' });
+
+    return co(function*() {
+      yield doc.save();
+
+      const d1 = yield M.findOne();
+      const d2 = yield M.findOne();
+
+      d1.name = 'bar';
+      yield d1.save();
+
+      d2.name = 'qux';
+      const err = yield d2.save().then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.name, 'VersionError');
+    });
+  });
 });

From 8cbaf0a1d9dfe35496b8d98ec33af6753224b8ca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 14:18:58 -0400
Subject: [PATCH 1098/2348] docs(browser): remove "Building with Webpack"
 section since we have a pre-built bundle

Re: #8435
Re: #9273
---
 docs/browser.pug     | 33 ++++++------------
 test/webpack.test.js | 82 --------------------------------------------
 2 files changed, 10 insertions(+), 105 deletions(-)
 delete mode 100644 test/webpack.test.js

diff --git a/docs/browser.pug b/docs/browser.pug
index bc15a1b91c8..d04e3ee6580 100644
--- a/docs/browser.pug
+++ b/docs/browser.pug
@@ -28,7 +28,14 @@ block content
     [discriminators](http://mongoosejs.com/docs/discriminators.html),
     or any other Mongoose feature other than schemas and validating documents.
 
-    Use the below syntax to access the Mongoose browser library.
+    Mongoose has a pre-built bundle of the browser library. If you're bundling your code with [Webpack](https://webpack.js.org/),
+    you should be able to import Mongoose's browser library as shown below if your Webpack `target` is `'web'`:
+
+    ```javascript
+    import mongoose from 'mongoose';
+    ```
+
+    You can use the below syntax to access the Mongoose browser library from Node.js:
 
     ```javascript
     // Using `require()`
@@ -40,7 +47,6 @@ block content
 
     <ul class="toc">
       <li><a href="#usage">Using the Browser Library</a></li>
-      <li><a href="#webpack">Building With Webpack</a></li>
     </ul>
 
 
@@ -50,7 +56,7 @@ block content
     is validating documents as shown below.
 
     ```javascript
-    import mongoose from 'mongoose/browser';
+    import mongoose from 'mongoose';
 
     // Mongoose's browser library does **not** have models. It only supports
     // schemas and documents. The primary use case is validating documents
@@ -60,23 +66,4 @@ block content
     }));
     // Prints an error because `name` is required.
     console.log(doc.validateSync());
-    ```
-
-    <h2 id="webpack">Building With Webpack</h2>
-
-    Mongoose uses [ES2015 (also known as ES6)](https://www.ecma-international.org/ecma-262/6.0/)
-    syntax, so in order to use Mongoose with older browsers you'll need to use
-    a tool like [Babel](https://www.npmjs.com/package/babel-cli). As of version
-    5.x, Mongoose no longer has an officially supported pre-built browser bundle,
-    you need to compile the browser library yourself.
-
-    To build Mongoose's browser library using Webpack, you'll need to use
-    [`babel-loader`](https://www.npmjs.com/package/babel-loader). Because of
-    how Webpack loads `require()` statements, it pulls in a lot of built-in
-    Node.js modules. In order to avoid this, you need to use the
-    [`node` Webpack config option](https://webpack.js.org/configuration/node/)
-    as shown below.
-
-    ```javascript
-    [require:webpack.*browser build$]
-    ```
+    ```
\ No newline at end of file
diff --git a/test/webpack.test.js b/test/webpack.test.js
deleted file mode 100644
index 31fcea670ae..00000000000
--- a/test/webpack.test.js
+++ /dev/null
@@ -1,82 +0,0 @@
-'use strict';
-
-const assert = require('assert');
-const utils = require('../lib/utils');
-const semver = require('semver');
-
-describe('webpack', function() {
-  it('works for browser build', function(done) {
-    // Below is the Webpack config Mongoose uses for testing
-    // acquit:ignore:start
-    // Webpack doesn't work on Node.js 4.x or 5.x, and very slow on
-    // Travis with 6.x and 7.x.
-    if (!semver.satisfies(process.version, '>=8.0.0')) {
-      this.skip();
-    }
-    const webpack = require('webpack');
-    this.timeout(90000);
-    // acquit:ignore:end
-    const webpackConfig = {
-      module: {
-        rules: [
-          {
-            test: /\.js$/,
-            include: [
-              /\/mongoose\//i,
-              /\/kareem\//i
-            ],
-            loader: 'babel-loader',
-            options: {
-              presets: ['es2015']
-            }
-          }
-        ]
-      },
-      node: {
-        // Replace these Node.js native modules with empty objects, Mongoose's
-        // browser library does not use them.
-        // See https://webpack.js.org/configuration/node/
-        dns: 'empty',
-        fs: 'empty',
-        module: 'empty',
-        net: 'empty',
-        tls: 'empty'
-      },
-      target: 'web',
-      mode: 'production'
-    };
-    // acquit:ignore:start
-    const webpackBundle = require('../webpack.config.js');
-    const baseConfig = require('../webpack.base.config.js');
-    assert.deepEqual(webpackConfig, baseConfig);
-    const webpackBundleForTest = Object.assign({}, webpackBundle, {
-      output: Object.assign({}, webpackBundle.output, { path: `${__dirname}/files` })
-    });
-    webpack(webpackBundleForTest, utils.tick(function(bundleBuildError, bundleBuildStats) {
-      assert.ifError(bundleBuildError);
-      assert.deepEqual(bundleBuildStats.compilation.errors, []);
-
-      // Avoid expressions in `require()` because that scares webpack (gh-6705)
-      assert.ok(!bundleBuildStats.compilation.warnings.
-        find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
-
-      const config = Object.assign({}, baseConfig, {
-        entry: ['./test/files/sample.js'],
-        output: {
-          path: `${__dirname}/files`
-        }
-      });
-      webpack(config, utils.tick(function(error, stats) {
-        assert.ifError(error);
-        assert.deepEqual(stats.compilation.errors, []);
-
-        // Avoid expressions in `require()` because that scares webpack (gh-6705)
-        assert.ok(!stats.compilation.warnings.
-          find(msg => msg.toString().startsWith('ModuleDependencyWarning:')));
-
-        done();
-      }));
-    }));
-    // acquit:ignore:end
-  });
-});

From 2a3d9fd25c075f348cebf927af91ed5c22c37599 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 16:12:02 -0400
Subject: [PATCH 1099/2348] fix(browser): upgrade babel to v7 to work around an
 issue with `extends Error`

Fix #9273
---
 lib/error/validation.js | 5 ++---
 package.json            | 7 ++++---
 webpack.base.config.js  | 2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/error/validation.js b/lib/error/validation.js
index 9d4453762a5..ccae07adff1 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -4,10 +4,9 @@
 
 'use strict';
 
-const MongooseError = require('./');
+const MongooseError = require('./mongooseError');
 const util = require('util');
 
-
 class ValidationError extends MongooseError {
   /**
    * Document Validation Error
@@ -108,4 +107,4 @@ function _generateMessage(err) {
  * Module exports
  */
 
-module.exports = exports = ValidationError;
+module.exports = ValidationError;
diff --git a/package.json b/package.json
index d25ea97ac89..286f621b812 100644
--- a/package.json
+++ b/package.json
@@ -32,12 +32,13 @@
     "sift": "7.0.1"
   },
   "devDependencies": {
+    "@babel/core": "7.10.5",
+    "@babel/preset-env": "7.10.4",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
     "async": "2.6.2",
-    "babel-loader": "7.1.4",
-    "babel-preset-es2015": "6.24.1",
+    "babel-loader": "8.1.0",
     "benchmark": "2.1.4",
     "bluebird": "3.5.5",
     "chalk": "2.4.2",
@@ -62,7 +63,7 @@
     "uuid": "2.0.3",
     "uuid-parse": "1.0.0",
     "validator": "10.8.0",
-    "webpack": "4.16.4"
+    "webpack": "4.44.0"
   },
   "directories": {
     "lib": "./lib/mongoose"
diff --git a/webpack.base.config.js b/webpack.base.config.js
index 33327617e57..1b2141aab16 100644
--- a/webpack.base.config.js
+++ b/webpack.base.config.js
@@ -11,7 +11,7 @@ module.exports = {
         ],
         loader: 'babel-loader',
         options: {
-          presets: ['es2015']
+          presets: ['@babel/preset-env']
         }
       }
     ]

From fd71093013ba68846782cdc6d93785bdb5ae0e96 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 16:17:05 -0400
Subject: [PATCH 1100/2348] style: fix lint

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 0f95ca1ef60..8484a0a4c9e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2950,10 +2950,10 @@ Model.findByIdAndRemove = function(id, options, callback) {
  *
  *     // Insert one new `Character` document
  *     await Character.create({ name: 'Jean-Luc Picard' });
- * 
+ *
  *     // Insert multiple new `Character` documents
  *     await Character.create([{ name: 'Will Riker' }, { name: 'Geordi LaForge' }]);
- * 
+ *
  *     // Create a new character within a transaction. Note that you **must**
  *     // pass an array as the first parameter to `create()` if you want to
  *     // specify options.

From 6e362a88da08328ea740718357b0629edd5a4045 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 16:59:58 -0400
Subject: [PATCH 1101/2348] test(document): repro #9275

---
 test/document.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index e13362b7bcc..ae3451ddd40 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9108,4 +9108,17 @@ describe('document', function() {
       yield doc.save();
     });
   });
+
+  it('allows removing boolean key by setting it to `undefined` (gh-9275)', function() {
+    const Test = db.model('Test', Schema({ a: Boolean }));
+
+    return co(function*() {
+      const doc = yield Test.create({ a: true });
+      doc.a = undefined;
+      yield doc.save();
+
+      const fromDb = yield Test.findOne().lean();
+      assert.ok(!('a' in fromDb));
+    });
+  });
 });

From 87597031522b38ab1e922c70fc16ac2ae08ef2ca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 17:01:26 -0400
Subject: [PATCH 1102/2348] fix(document): allow unsetting boolean field by
 setting the field to `undefined`

Fix #9275
---
 lib/schema/boolean.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index eb904ccd34e..37b4d51e0a0 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -237,7 +237,7 @@ SchemaBoolean.prototype._castNullish = function _castNullish(v) {
     this.constructor.cast() :
     SchemaBoolean.cast();
   if (castBoolean == null) {
-    return null;
+    return v;
   }
   if (castBoolean.convertToFalse instanceof Set && castBoolean.convertToFalse.has(v)) {
     return false;
@@ -245,7 +245,7 @@ SchemaBoolean.prototype._castNullish = function _castNullish(v) {
   if (castBoolean.convertToTrue instanceof Set && castBoolean.convertToTrue.has(v)) {
     return true;
   }
-  return null;
+  return v;
 };
 
 /*!

From 17fbcca7a00f651c4e6e12c6780f8c97169ed005 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 17:09:26 -0400
Subject: [PATCH 1103/2348] docs: correct link

---
 docs/migrating_to_5.pug | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/migrating_to_5.pug b/docs/migrating_to_5.pug
index 04729953669..9d675af697c 100644
--- a/docs/migrating_to_5.pug
+++ b/docs/migrating_to_5.pug
@@ -105,7 +105,7 @@ block content
       Connection Logic and `useMongoClient`
     </a></h3>
 
-    The [`useMongoClient` option](http://mongoosejs.com/docs/4.x/docs/connections.html#use-mongo-client) was
+    The [`useMongoClient` option](/docs/4.x/docs/connections.html#use-mongo-client) was
     removed in Mongoose 5, it is now always `true`. As a consequence, Mongoose 5
     no longer supports several function signatures for `mongoose.connect()` that
     worked in Mongoose 4.x if the `useMongoClient` option was off. Below are some
@@ -489,7 +489,7 @@ block content
     </a></h3>
 
     Mongoose 5.x uses version 3.x of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb). MongoDB driver 3.x changed the format of
-    the result of [`bulkWrite()` calls](http://mongoosejs.com//docs/api.html#model_Model.bulkWrite) so there is no longer a top-level `nInserted`, `nModified`, etc. property. The new result object structure is [described here](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult).
+    the result of [`bulkWrite()` calls](/docs/api.html#model_Model.bulkWrite) so there is no longer a top-level `nInserted`, `nModified`, etc. property. The new result object structure is [described here](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult).
 
     ```javascript
     const Model = mongoose.model('Test', new Schema({ name: String }));
@@ -569,4 +569,4 @@ block content
 
     ```javascript
     mongoose.connect(uri, { tlsInsecure: false }); // Opt out of additional SSL validation
-    ```
\ No newline at end of file
+    ```

From 4d0a19e53a371b9af25ead01d9e93808d8436b6e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 17:23:35 -0400
Subject: [PATCH 1104/2348] chore: release 5.9.26

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c86789befba..c106837a892 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.9.26 / 2020-07-27
+===================
+ * fix(document): allow unsetting boolean field by setting the field to `undefined` #9275
+ * fix(document): throw error when overwriting a single nested subdoc changes an immutable path within the subdoc #9281
+ * fix(timestamps): apply timestamps to `bulkWrite()` updates when not using `$set` #9268
+ * fix(browser): upgrade babel to v7 to work around an issue with `extends Error` #9273
+ * fix: make subdocument's `invalidate()` methods have the same return value as top-level document #9271
+ * docs(model): make `create()` docs use async/await, and add another warning about how `create()` with options requires array syntax #9280
+ * docs(connections): clarify that Mongoose can emit 'connected' when reconnecting after losing connectivity #9240
+ * docs(populate): clarify that you can't filter based on foreign document properties when populating #9279
+ * docs(document+model): clarify how `validateModifiedOnly` option works #9263
+ * docs: remove extra poolSize option in comment #9270 [shahvicky](https://github.com/shahvicky)
+ * docs: point bulkWrite() link to mongoose docs instead of localhost #9284
+
 5.9.25 / 2020-07-17
 ===================
  * fix(discriminator): allow passing a compiled model's schema as a parameter to `discriminator()` #9238
diff --git a/package.json b/package.json
index 286f621b812..ab87a2c086e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.25",
+  "version": "5.9.26",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From c55fba5e06bd182258d2009f088abaca8954c28d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 17:30:26 -0400
Subject: [PATCH 1105/2348] chore: fix docs build

---
 website.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/website.js b/website.js
index 23010b7bff2..6408030ccf9 100644
--- a/website.js
+++ b/website.js
@@ -22,7 +22,6 @@ markdown.setOptions({
 });
 
 const tests = [
-  ...acquit.parse(fs.readFileSync('./test/webpack.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/geojson.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/docs/transactions.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/schema.alias.test.js').toString()),

From dcccbcc842c1b90072b19ff257eee64a55b9c817 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Jul 2020 17:36:24 -0400
Subject: [PATCH 1106/2348] chore: add changelog to npmignore

---
 .npmignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.npmignore b/.npmignore
index 4d835952c43..fce500a605e 100644
--- a/.npmignore
+++ b/.npmignore
@@ -24,6 +24,7 @@ examples/
 .vscode
 .eslintignore
 CONTRIBUTING.md
+HISTORY.md
 format_deps.js
 release-items.md
 static.js

From ec19595270916540b4feff46004435671cc7cb73 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 28 Jul 2020 12:07:44 -0400
Subject: [PATCH 1107/2348] feat(query): handle casting `$or` when each clause
 contains a different discriminator key

Fix #9018
---
 lib/cast.js                                   |  5 ++++
 .../getSchemaDiscriminatorByValue.js          | 24 +++++++++++++++++++
 test/model.discriminator.querying.test.js     | 24 ++++++++++++++++++-
 3 files changed, 52 insertions(+), 1 deletion(-)
 create mode 100644 lib/helpers/discriminator/getSchemaDiscriminatorByValue.js

diff --git a/lib/cast.js b/lib/cast.js
index b047939948f..1c24bc7fe65 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -9,6 +9,7 @@ const StrictModeError = require('./error/strict');
 const Types = require('./schema/index');
 const castTextSearch = require('./schema/operators/text');
 const get = require('./helpers/get');
+const getSchemaDiscriminatorByValue = require('./helpers/discriminator/getSchemaDiscriminatorByValue');
 const isOperator = require('./helpers/query/isOperator');
 const util = require('util');
 const isObject = require('./helpers/isObject');
@@ -42,6 +43,10 @@ module.exports = function cast(schema, obj, options, context) {
     delete obj._bsontype;
   }
 
+  if (schema != null && schema.discriminators != null && obj[schema.options.discriminatorKey] != null) {
+    schema = getSchemaDiscriminatorByValue(schema, obj[schema.options.discriminatorKey]) || schema;
+  }
+
   const paths = Object.keys(obj);
   let i = paths.length;
   let _keys;
diff --git a/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js b/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js
new file mode 100644
index 00000000000..f3e71a093a9
--- /dev/null
+++ b/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js
@@ -0,0 +1,24 @@
+'use strict';
+
+/*!
+* returns discriminator by discriminatorMapping.value
+*
+* @param {Schema} schema
+* @param {string} value
+*/
+
+module.exports = function getSchemaDiscriminatorByValue(schema, value) {
+  if (schema == null || schema.discriminators == null) {
+    return null;
+  }
+  for (const key of Object.keys(schema.discriminators)) {
+    const discriminatorSchema = schema.discriminators[key];
+    if (discriminatorSchema.discriminatorMapping == null) {
+      continue;
+    }
+    if (discriminatorSchema.discriminatorMapping.value === value) {
+      return discriminatorSchema;
+    }
+  }
+  return null;
+};
\ No newline at end of file
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index c7e981fe39c..4cd246f3b3e 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -27,7 +27,7 @@ function BaseSchema() {
 util.inherits(BaseSchema, Schema);
 
 const EventSchema = new BaseSchema();
-const ImpressionEventSchema = new BaseSchema();
+const ImpressionEventSchema = new BaseSchema({ element: String });
 const ConversionEventSchema = new BaseSchema({ revenue: Number });
 const SecretEventSchema = new BaseSchema({ secret: { type: String, select: false } });
 
@@ -178,6 +178,28 @@ describe('model', function() {
         checkHydratesCorrectModels({ name: 1 }, done);
       });
 
+      it('casts underneath $or if discriminator key in filter (gh-9018)', function() {
+        return co(function*() {
+          yield ImpressionEvent.create({ name: 'Impression event', element: '42' });
+          yield ConversionEvent.create({ name: 'Conversion event', revenue: 1.337 });
+
+          let docs = yield BaseEvent.find({ __t: 'Impression', element: 42 });
+          assert.equal(docs.length, 1);
+          assert.equal(docs[0].name, 'Impression event');
+
+          docs = yield BaseEvent.find({ $or: [{ __t: 'Impression', element: 42 }] });
+          assert.equal(docs.length, 1);
+          assert.equal(docs[0].name, 'Impression event');
+
+          docs = yield BaseEvent.find({
+            $or: [{ __t: 'Impression', element: 42 }, { __t: 'Conversion', revenue: '1.337' }]
+          }).sort({ __t: 1 });
+          assert.equal(docs.length, 2);
+          assert.equal(docs[0].name, 'Conversion event');
+          assert.equal(docs[1].name, 'Impression event');
+        });
+      });
+
       describe('discriminator model only finds documents of its type', function() {
 
         describe('using "ModelDiscriminator#findById"', function() {

From f8ae13dcacffac7c5b65bdd84b93fa5a5de04b26 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 29 Jul 2020 18:50:42 -0400
Subject: [PATCH 1108/2348] docs(transactions): make transactions docs use
 async/await for readability

Fix #9204
---
 test/docs/transactions.test.js        | 366 --------------------------
 test/es-next.test.js                  |   1 +
 test/es-next/transactions.test.es6.js | 356 +++++++++++++++++++++++++
 3 files changed, 357 insertions(+), 366 deletions(-)
 delete mode 100644 test/docs/transactions.test.js
 create mode 100644 test/es-next/transactions.test.es6.js

diff --git a/test/docs/transactions.test.js b/test/docs/transactions.test.js
deleted file mode 100644
index e27662861d8..00000000000
--- a/test/docs/transactions.test.js
+++ /dev/null
@@ -1,366 +0,0 @@
-'use strict';
-
-const assert = require('assert');
-const co = require('co');
-const start = require('../common');
-
-const mongoose = start.mongoose;
-const Schema = mongoose.Schema;
-
-describe('transactions', function() {
-  let db;
-  let _skipped = false;
-
-  before(function() {
-    if (!process.env.REPLICA_SET) {
-      _skipped = true;
-      this.skip();
-    }
-    db = start({ replicaSet: process.env.REPLICA_SET });
-
-    return db.
-      then(() => {
-        // Skip if not a repl set
-        if (db.client.topology.constructor.name !== 'ReplSet' &&
-            !db.client.topology.s.description.type.includes('ReplicaSet')) {
-          _skipped = true;
-          this.skip();
-
-          throw new Error('skip');
-        }
-      }).
-      then(() => new Promise((resolve, reject) => {
-        start.mongodVersion(function(err, version) {
-          if (err) {
-            return reject(err);
-          }
-          resolve(version);
-        });
-      })).
-      then(version => {
-        if (version[0] < 4) {
-          _skipped = true;
-          this.skip();
-        }
-      }).
-      catch(() => {
-        _skipped = true;
-        this.skip();
-      });
-  });
-
-  it('basic example', function() {
-    const Customer = db.model('Customer', new Schema({ name: String }));
-
-    let session = null;
-    return Customer.createCollection().
-      then(() => db.startSession()).
-      then(_session => {
-        session = _session;
-        // Start a transaction
-        session.startTransaction();
-        // This `create()` is part of the transaction because of the `session`
-        // option.
-        return Customer.create([{ name: 'Test' }], { session: session });
-      }).
-      // Transactions execute in isolation, so unless you pass a `session`
-      // to `findOne()` you won't see the document until the transaction
-      // is committed.
-      then(() => Customer.findOne({ name: 'Test' })).
-      then(doc => assert.ok(!doc)).
-      // This `findOne()` will return the doc, because passing the `session`
-      // means this `findOne()` will run as part of the transaction.
-      then(() => Customer.findOne({ name: 'Test' }).session(session)).
-      then(doc => assert.ok(doc)).
-      // Once the transaction is committed, the write operation becomes
-      // visible outside of the transaction.
-      then(() => session.commitTransaction()).
-      then(() => Customer.findOne({ name: 'Test' })).
-      then(doc => assert.ok(doc)).
-      then(() => session.endSession());
-  });
-
-  it('withTransaction', function() {
-    // acquit:ignore:start
-    const Customer = db.model('Customer_withTrans', new Schema({ name: String }));
-    // acquit:ignore:end
-
-    let session = null;
-    return Customer.createCollection().
-      then(() => Customer.startSession()).
-      // The `withTransaction()` function's first parameter is a function
-      // that returns a promise.
-      then(_session => {
-        session = _session;
-        return session.withTransaction(() => {
-          return Customer.create([{ name: 'Test' }], { session: session });
-        });
-      }).
-      then(() => Customer.countDocuments()).
-      then(count => assert.strictEqual(count, 1)).
-      then(() => session.endSession());
-  });
-
-  it('abort', function() {
-    // acquit:ignore:start
-    const Customer = db.model('Customer0', new Schema({ name: String }));
-    // acquit:ignore:end
-    let session = null;
-    return Customer.createCollection().
-      then(() => Customer.startSession()).
-      then(_session => {
-        session = _session;
-        session.startTransaction();
-        return Customer.create([{ name: 'Test' }], { session: session });
-      }).
-      then(() => Customer.create([{ name: 'Test2' }], { session: session })).
-      then(() => session.abortTransaction()).
-      then(() => Customer.countDocuments()).
-      then(count => assert.strictEqual(count, 0)).
-      then(() => session.endSession());
-  });
-
-  it('save', function() {
-    const User = db.model('User', new Schema({ name: String }));
-
-    let session = null;
-    return User.createCollection().
-      then(() => db.startSession()).
-      then(_session => {
-        session = _session;
-        return User.create({ name: 'foo' });
-      }).
-      then(() => {
-        session.startTransaction();
-        return User.findOne({ name: 'foo' }).session(session);
-      }).
-      then(user => {
-        // Getter/setter for the session associated with this document.
-        assert.ok(user.$session());
-        user.name = 'bar';
-        // By default, `save()` uses the associated session
-        return user.save();
-      }).
-      then(() => User.findOne({ name: 'bar' })).
-      // Won't find the doc because `save()` is part of an uncommitted transaction
-      then(doc => assert.ok(!doc)).
-      then(() => session.commitTransaction()).
-      then(() => session.endSession()).
-      then(() => User.findOne({ name: 'bar' })).
-      then(doc => assert.ok(doc));
-  });
-
-  it('create (gh-6909)', function() {
-    const User = db.model('gh6909_User', new Schema({ name: String }));
-
-    let session = null;
-    return User.createCollection().
-      then(() => db.startSession()).
-      then(_session => {
-        session = _session;
-        session.startTransaction();
-        return User.create([{ name: 'foo' }], { session: session });
-      }).
-      then(users => {
-        users[0].name = 'bar';
-        return users[0].save();
-      }).
-      then(() => User.findOne({ name: 'bar' })).
-      then(user => {
-        // Not in transaction, shouldn't find it
-        assert.ok(!user);
-
-        session.commitTransaction();
-      });
-  });
-
-  it('aggregate', function() {
-    const Event = db.model('Event', new Schema({ createdAt: Date }), 'Event');
-
-    let session = null;
-    return Event.createCollection().
-      then(() => db.startSession()).
-      then(_session => {
-        session = _session;
-        session.startTransaction();
-        return Event.insertMany([
-          { createdAt: new Date('2018-06-01') },
-          { createdAt: new Date('2018-06-02') },
-          { createdAt: new Date('2017-06-01') },
-          { createdAt: new Date('2017-05-31') }
-        ], { session: session });
-      }).
-      then(() => Event.aggregate([
-        {
-          $group: {
-            _id: {
-              month: { $month: '$createdAt' },
-              year: { $year: '$createdAt' }
-            },
-            count: { $sum: 1 }
-          }
-        },
-        { $sort: { count: -1, '_id.year': -1, '_id.month': -1 } }
-      ]).session(session)).
-      then(res => assert.deepEqual(res, [
-        { _id: { month: 6, year: 2018 }, count: 2 },
-        { _id: { month: 6, year: 2017 }, count: 1 },
-        { _id: { month: 5, year: 2017 }, count: 1 }
-      ])).
-      then(() => session.commitTransaction()).
-      then(() => session.endSession());
-  });
-
-  describe('populate (gh-6754)', function() {
-    let Author;
-    let Article;
-    let session;
-
-    before(function() {
-      if (_skipped) {
-        this.skip();
-        return; // https://github.com/mochajs/mocha/issues/2546
-      }
-
-      Author = db.model('Author', new Schema({ name: String }), 'Author');
-      Article = db.model('Article', new Schema({
-        author: {
-          type: mongoose.Schema.Types.ObjectId,
-          ref: 'Author'
-        }
-      }), 'Article');
-
-      return Author.createCollection().
-        then(() => Article.createCollection());
-    });
-
-    beforeEach(function() {
-      return Author.deleteMany({}).
-        then(() => Article.deleteMany({})).
-        then(() => db.startSession()).
-        then(_session => {
-          session = _session;
-          session.startTransaction();
-        });
-    });
-
-    afterEach(function() {
-      session.commitTransaction();
-      return session.endSession();
-    });
-
-    it('`populate()` uses the querys session', function() {
-      return Author.create([{ name: 'Val' }], { session: session }).
-        then(authors => Article.create([{ author: authors[0]._id }], { session: session })).
-        then(articles => {
-          return Article.
-            findById(articles[0]._id).
-            session(session).
-            populate('author');
-        }).
-        then(article => assert.equal(article.author.name, 'Val'));
-    });
-
-    it('can override `populate()` session', function() {
-      return Author.create([{ name: 'Val' }], { session: session }).
-        // Article created _outside_ the transaction
-        then(authors => Article.create([{ author: authors[0]._id }])).
-        then(articles => {
-          return Article.
-            findById(articles[0]._id).
-            populate({ path: 'author', options: { session: session } });
-        }).
-        then(article => assert.equal(article.author.name, 'Val'));
-    });
-
-    it('`execPopulate()` uses the documents `$session()` by default', function() {
-      return Author.create([{ name: 'Val' }], { session: session }).
-        then(authors => Article.create([{ author: authors[0]._id }], { session: session })).
-        // By default, the populate query should use the associated `$session()`
-        then(articles => Article.findById(articles[0]._id).session(session)).
-        then(article => {
-          assert.ok(article.$session());
-          return article.populate('author').execPopulate();
-        }).
-        then(article => assert.equal(article.author.name, 'Val'));
-    });
-
-    it('`execPopulate()` supports overwriting the session', function() {
-      return Author.create([{ name: 'Val' }], { session: session }).
-        then(authors => Article.create([{ author: authors[0]._id }], { session: session })).
-        then(() => Article.findOne().session(session)).
-        then(article => {
-          return article.
-            populate({ path: 'author', options: { session: null } }).
-            execPopulate();
-        }).
-        then(article => assert.ok(!article.author));
-    });
-  });
-
-  it('deleteOne and deleteMany (gh-7857)(gh-6805)', function() {
-    const Character = db.model('Character', new Schema({ name: String }), 'Character');
-
-    let session = null;
-    return Character.createCollection().
-      then(() => db.startSession()).
-      then(_session => {
-        session = _session;
-        session.startTransaction();
-        return Character.insertMany([
-          { name: 'Tyrion Lannister' },
-          { name: 'Cersei Lannister' },
-          { name: 'Jon Snow' },
-          { name: 'Daenerys Targaryen' }
-        ], { session: session });
-      }).
-      then(() => Character.deleteMany({ name: /Lannister/ }, { session: session })).
-      then(() => Character.deleteOne({ name: 'Jon Snow' }, { session: session })).
-      then(() => Character.find({}).session(session)).
-      then(res => assert.equal(res.length, 1)).
-      then(() => session.commitTransaction()).
-      then(() => session.endSession());
-  });
-
-  it('remove, update, updateOne (gh-7455)', function() {
-    const Character = db.model('gh7455_Character', new Schema({ name: String, title: String }, { versionKey: false }));
-
-    return co(function*() {
-      yield Character.create({ name: 'Tyrion Lannister' });
-      const session = yield db.startSession();
-
-      session.startTransaction();
-
-      const tyrion = yield Character.findOne().session(session);
-
-      yield tyrion.updateOne({ title: 'Hand of the King' });
-
-      // Session isn't committed
-      assert.equal(yield Character.countDocuments({ title: /hand/i }), 0);
-
-      yield tyrion.remove();
-
-      // Undo both update and delete since doc should pull from `$session()`
-      yield session.abortTransaction();
-      session.endSession();
-
-      const fromDb = yield Character.findOne().then(doc => doc.toObject());
-      delete fromDb._id;
-      assert.deepEqual(fromDb, { name: 'Tyrion Lannister' });
-    });
-  });
-
-  it('save() with no changes (gh-8571)', function() {
-    return co(function*() {
-      const Test = db.model('Test', Schema({ name: String }));
-
-      yield Test.createCollection();
-      const session = yield db.startSession();
-      yield session.withTransaction(() => co(function*() {
-        const test = yield Test.create([{}], { session }).then(res => res[0]);
-        yield test.save(); // throws DocumentNotFoundError
-      }));
-      yield session.endSession();
-    });
-  });
-});
diff --git a/test/es-next.test.js b/test/es-next.test.js
index 2fb5cae2186..9cd073d96a6 100644
--- a/test/es-next.test.js
+++ b/test/es-next.test.js
@@ -11,4 +11,5 @@ if (parseInt(process.versions.node.split('.')[0], 10) >= 8) {
   require('./es-next/getters-setters.test.es6.js');
   require('./es-next/promises.test.es6.js');
   require('./es-next/virtuals.test.es6.js');
+  require('./es-next/transactions.test.es6.js');
 }
diff --git a/test/es-next/transactions.test.es6.js b/test/es-next/transactions.test.es6.js
new file mode 100644
index 00000000000..806d9bcac68
--- /dev/null
+++ b/test/es-next/transactions.test.es6.js
@@ -0,0 +1,356 @@
+'use strict';
+
+const assert = require('assert');
+const co = require('co');
+const start = require('../common');
+
+const mongoose = start.mongoose;
+const Schema = mongoose.Schema;
+
+describe('transactions', function() {
+  let db;
+  let _skipped = false;
+
+  before(function() {
+    if (!process.env.REPLICA_SET) {
+      _skipped = true;
+      this.skip();
+    }
+    db = start({ replicaSet: process.env.REPLICA_SET });
+
+    return db.
+      then(() => {
+        // Skip if not a repl set
+        if (db.client.topology.constructor.name !== 'ReplSet' &&
+            !db.client.topology.s.description.type.includes('ReplicaSet')) {
+          _skipped = true;
+          this.skip();
+
+          throw new Error('skip');
+        }
+      }).
+      then(() => new Promise((resolve, reject) => {
+        start.mongodVersion(function(err, version) {
+          if (err) {
+            return reject(err);
+          }
+          resolve(version);
+        });
+      })).
+      then(version => {
+        if (version[0] < 4) {
+          _skipped = true;
+          this.skip();
+        }
+      }).
+      catch(() => {
+        _skipped = true;
+        this.skip();
+      });
+  });
+
+  it('basic example', async function() {
+    const Customer = db.model('Customer', new Schema({ name: String }));
+
+    // acquit:ignore:start
+    await Customer.createCollection();
+    // acquit:ignore:end
+    
+    const session = await db.startSession();
+    session.startTransaction();
+
+    // This `create()` is part of the transaction because of the `session`
+    // option.
+    await Customer.create([{ name: 'Test' }], { session: session });
+
+    // Transactions execute in isolation, so unless you pass a `session`
+    // to `findOne()` you won't see the document until the transaction
+    // is committed.
+    let doc = await Customer.findOne({ name: 'Test' });
+    assert.ok(!doc);
+
+    // This `findOne()` will return the doc, because passing the `session`
+    // means this `findOne()` will run as part of the transaction.
+    doc = await Customer.findOne({ name: 'Test' }).session(session);
+    assert.ok(doc);
+
+    // Once the transaction is committed, the write operation becomes
+    // visible outside of the transaction.
+    await session.commitTransaction();
+    doc = await Customer.findOne({ name: 'Test' });
+    assert.ok(doc);
+
+    session.endSession();
+  });
+
+  it('withTransaction', async function() {
+    // acquit:ignore:start
+    const Customer = db.model('Customer_withTrans', new Schema({ name: String }));
+    await Customer.createCollection();
+    // acquit:ignore:end
+
+    const session = await Customer.startSession();
+
+    // The `withTransaction()` function's first parameter is a function
+    // that returns a promise.
+    await session.withTransaction(() => {
+      return Customer.create([{ name: 'Test' }], { session: session })
+    });
+
+    const count = await Customer.countDocuments();
+    assert.strictEqual(count, 1);
+
+    session.endSession();
+  });
+
+  it('abort', async function() {
+    // acquit:ignore:start
+    const Customer = db.model('Customer0', new Schema({ name: String }));
+    await Customer.createCollection();
+    // acquit:ignore:end
+    const session = await Customer.startSession();
+    session.startTransaction();
+
+    await Customer.create([{ name: 'Test' }], { session: session });
+    await Customer.create([{ name: 'Test2' }], { session: session });
+
+    await session.abortTransaction();
+
+    const count = await Customer.countDocuments();
+    assert.strictEqual(count, 0);
+
+    session.endSession();
+  });
+
+  it('save', async function() {
+    const User = db.model('User', new Schema({ name: String }));
+    // acquit:ignore:start
+    await User.createCollection();
+    // acquit:ignore:end
+    const session = await db.startSession();
+    session.startTransaction();
+
+    await User.create({ name: 'foo' });
+
+    const user = await User.findOne({ name: 'foo' }).session(session);
+    // Getter/setter for the session associated with this document.
+    assert.ok(user.$session());
+    user.name = 'bar';
+    // By default, `save()` uses the associated session
+    await user.save();
+
+    // Won't find the doc because `save()` is part of an uncommitted transaction
+    let doc = await User.findOne({ name: 'bar' });
+    assert.ok(!doc);
+
+    await session.commitTransaction();
+    session.endSession();
+
+    doc = await User.findOne({ name: 'bar' });
+    assert.ok(doc);
+  });
+
+  it('create (gh-6909)', async function() {
+    // acquit:ignore:start
+    const User = db.model('gh6909_User', new Schema({ name: String }));
+    await User.createCollection();
+    // acquit:ignore:end
+    const session = await db.startSession();
+    session.startTransaction();
+
+    const users = await User.create([{ name: 'foo' }], { session: session });
+    users[0].name = 'bar';
+    await users[0].save();
+
+    const user = await User.findOne({ name: 'bar' });
+    assert.ok(!user);
+
+    await session.commitTransaction();
+    session.endSession();
+  });
+
+  it('aggregate', async function() {
+    const Event = db.model('Event', new Schema({ createdAt: Date }), 'Event');
+    // acquit:ignore:start
+    await Event.createCollection();
+    // acquit:ignore:end
+    const session = await db.startSession();
+    session.startTransaction();
+
+    await Event.insertMany([
+      { createdAt: new Date('2018-06-01') },
+      { createdAt: new Date('2018-06-02') },
+      { createdAt: new Date('2017-06-01') },
+      { createdAt: new Date('2017-05-31') }
+    ], { session: session });
+
+    const res = await Event.aggregate([
+      {
+        $group: {
+          _id: {
+            month: { $month: '$createdAt' },
+            year: { $year: '$createdAt' }
+          },
+          count: { $sum: 1 }
+        }
+      },
+      { $sort: { count: -1, '_id.year': -1, '_id.month': -1 } }
+    ]).session(session);
+
+    assert.deepEqual(res, [
+      { _id: { month: 6, year: 2018 }, count: 2 },
+      { _id: { month: 6, year: 2017 }, count: 1 },
+      { _id: { month: 5, year: 2017 }, count: 1 }
+    ]);
+
+    await session.commitTransaction();
+    session.endSession();
+  });
+
+  describe('populate (gh-6754)', function() {
+    let Author;
+    let Article;
+    let session;
+
+    before(function() {
+      if (_skipped) {
+        this.skip();
+        return; // https://github.com/mochajs/mocha/issues/2546
+      }
+
+      Author = db.model('Author', new Schema({ name: String }), 'Author');
+      Article = db.model('Article', new Schema({
+        author: {
+          type: mongoose.Schema.Types.ObjectId,
+          ref: 'Author'
+        }
+      }), 'Article');
+
+      return Author.createCollection().
+        then(() => Article.createCollection());
+    });
+
+    beforeEach(function() {
+      return Author.deleteMany({}).
+        then(() => Article.deleteMany({})).
+        then(() => db.startSession()).
+        then(_session => {
+          session = _session;
+          session.startTransaction();
+        });
+    });
+
+    afterEach(async function() {
+      await session.commitTransaction();
+      session.endSession();
+    });
+
+    it('`populate()` uses the querys session', async function() {
+      const authors = await Author.create([{ name: 'Val' }], { session: session });
+      const articles = await Article.create([{ author: authors[0]._id }], { session: session });
+
+      const article = await Article.
+        findById(articles[0]._id).
+        session(session).
+        populate('author');
+      assert.equal(article.author.name, 'Val');
+    });
+
+    it('can override `populate()` session', async function() {
+      const authors = await Author.create([{ name: 'Val' }], { session: session });
+      // Article created _outside_ the transaction
+      const articles = await Article.create([{ author: authors[0]._id }]);
+      const article = await Article.
+        findById(articles[0]._id).
+        populate({ path: 'author', options: { session: session } });
+
+      assert.equal(article.author.name, 'Val');
+    });
+
+    it('`execPopulate()` uses the documents `$session()` by default', async function() {
+      const authors = await Author.create([{ name: 'Val' }], { session: session });
+      const articles = await Article.create([{ author: authors[0]._id }], { session: session });
+
+      // By default, the populate query should use the associated `$session()`
+      const article = await Article.findById(articles[0]._id).session(session);
+
+      assert.ok(article.$session());
+      await article.populate('author').execPopulate();
+
+      assert.equal(article.author.name, 'Val');
+    });
+
+    it('`execPopulate()` supports overwriting the session', async function() {
+      const authors = await Author.create([{ name: 'Val' }], { session: session });
+      await Article.create([{ author: authors[0]._id }], { session: session });
+
+      const article = await Article.findOne().session(session);
+
+      await article.
+        populate({ path: 'author', options: { session: null } }).
+        execPopulate();
+      assert.ok(!article.author);
+    });
+  });
+
+  it('deleteOne and deleteMany (gh-7857)(gh-6805)', async function() {
+    const Character = db.model('Character', new Schema({ name: String }), 'Character');
+    // acquit:ignore:start
+    await Character.createCollection();
+    // acquit:ignore:end
+    const session = await db.startSession();
+    session.startTransaction();
+
+    await Character.insertMany([
+      { name: 'Tyrion Lannister' },
+      { name: 'Cersei Lannister' },
+      { name: 'Jon Snow' },
+      { name: 'Daenerys Targaryen' }
+    ], { session: session });
+
+    await Character.deleteMany({ name: /Lannister/ }, { session: session });
+    await Character.deleteOne({ name: 'Jon Snow' }, { session: session });
+
+    const res = await Character.find({}).session(session);
+    assert.equal(res.length, 1);
+    
+    await session.commitTransaction();
+    session.endSession();
+  });
+
+  it('remove, update, updateOne (gh-7455)', async function() {
+    const Character = db.model('gh7455_Character', new Schema({ name: String, title: String }, { versionKey: false }));
+
+    await Character.create({ name: 'Tyrion Lannister' });
+
+    const session = await db.startSession();
+    session.startTransaction();
+
+    const tyrion = await Character.findOne().session(session);
+    await tyrion.updateOne({ title: 'Hand of the King' });
+
+    // Session isn't committed
+    assert.equal(await Character.countDocuments({ title: /hand/i }), 0);
+
+    await tyrion.remove();
+
+    // Undo both update and delete since doc should pull from `$session()`
+    await session.abortTransaction();
+    session.endSession();
+
+    const fromDb = await Character.findOne().then(doc => doc.toObject());
+    assert.deepEqual(fromDb.name, 'Tyrion Lannister');
+  });
+
+  it('save() with no changes (gh-8571)', async function() {
+    const Test = db.model('Test', Schema({ name: String }));
+
+    await Test.createCollection();
+    const session = await db.startSession();
+    await session.withTransaction(async () => {
+      const test = await Test.create([{}], { session }).then(res => res[0]);
+      await test.save(); // throws DocumentNotFoundError
+    });
+    session.endSession();
+  });
+});

From 57b1bc6ed2cd7f189d53eaa2c8a15fdb4ae89575 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 31 Jul 2020 08:10:09 +0200
Subject: [PATCH 1109/2348] bump mongodb driver to 3.5.10

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index ab87a2c086e..8df50d56ae3 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.5.9",
+    "mongodb": "3.5.10",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From 21de3863bd92e2ee5830eebc6e69503f646ff9a5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jul 2020 10:32:05 -0400
Subject: [PATCH 1110/2348] test: move some more transactions tests to
 async/await

---
 test/es-next/transactions.test.es6.js | 89 +++++++++++++--------------
 1 file changed, 42 insertions(+), 47 deletions(-)

diff --git a/test/es-next/transactions.test.es6.js b/test/es-next/transactions.test.es6.js
index f8d32b4828c..560bcbfc33c 100644
--- a/test/es-next/transactions.test.es6.js
+++ b/test/es-next/transactions.test.es6.js
@@ -353,60 +353,55 @@ describe('transactions', function() {
     session.endSession();
   });
 
-  it('correct `isNew` after abort (gh-8852)', function() {
-    return co(function*() {
-      const schema = Schema({ name: String });
-
-      const Test = db.model('gh8852', schema);
-
-      yield Test.createCollection();
-      const doc = new Test({ name: 'foo' });
-      yield db.
-        transaction(session => co(function*() {
-          yield doc.save({ session });
-          assert.ok(!doc.isNew);
-          throw new Error('Oops');
-        })).
-        catch(err => assert.equal(err.message, 'Oops'));
-      assert.ok(doc.isNew);
-    });
-  });
+  it('correct `isNew` after abort (gh-8852)', async function() {
+    const schema = Schema({ name: String });
 
-  it('can save document after aborted transaction (gh-8380)', function() {
-    return co(function*() {
-      const schema = Schema({ name: String, arr: [String], arr2: [String] });
+    const Test = db.model('gh8852', schema);
 
-      const Test = db.model('gh8380', schema);
+    await Test.createCollection();
+    const doc = new Test({ name: 'foo' });
+    await db.
+      transaction(async (session) =>  {
+        await doc.save({ session });
+        assert.ok(!doc.isNew);
+        throw new Error('Oops');
+      }).
+      catch(err => assert.equal(err.message, 'Oops'));
+    assert.ok(doc.isNew);
+  });
 
-      yield Test.createCollection();
-      yield Test.create({ name: 'foo', arr: ['bar'], arr2: ['foo'] });
-      const doc = yield Test.findOne();
-      yield db.
-        transaction(session => co(function*() {
-          doc.arr.pull('bar');
-          doc.arr2.push('bar');
+  it('can save document after aborted transaction (gh-8380)', async function() {
+    const schema = Schema({ name: String, arr: [String], arr2: [String] });
 
-          yield doc.save({ session });
+    const Test = db.model('gh8380', schema);
 
-          doc.name = 'baz';
-          throw new Error('Oops');
-        })).
-        catch(err => {
-          assert.equal(err.message, 'Oops');
-        });
+    await Test.createCollection();
+    await Test.create({ name: 'foo', arr: ['bar'], arr2: ['foo'] });
+    const doc = await Test.findOne();
+    await db.
+      transaction(async (session) => {
+        doc.arr.pull('bar');
+        doc.arr2.push('bar');
+
+        await doc.save({ session });
+        doc.name = 'baz';
+        throw new Error('Oops');
+      }).
+      catch(err => {
+        assert.equal(err.message, 'Oops');
+      });
 
-      const changes = doc.$__delta()[1];
-      assert.equal(changes.$set.name, 'baz');
-      assert.deepEqual(changes.$pullAll.arr, ['bar']);
-      assert.deepEqual(changes.$push.arr2, { $each: ['bar'] });
-      assert.ok(!changes.$set.arr2);
+    const changes = doc.$__delta()[1];
+    assert.equal(changes.$set.name, 'baz');
+    assert.deepEqual(changes.$pullAll.arr, ['bar']);
+    assert.deepEqual(changes.$push.arr2, { $each: ['bar'] });
+    assert.ok(!changes.$set.arr2);
 
-      yield doc.save({ session: null });
+    await doc.save({ session: null });
 
-      const newDoc = yield Test.collection.findOne();
-      assert.equal(newDoc.name, 'baz');
-      assert.deepEqual(newDoc.arr, []);
-      assert.deepEqual(newDoc.arr2, ['foo', 'bar']);
-    });
+    const newDoc = await Test.collection.findOne();
+    assert.equal(newDoc.name, 'baz');
+    assert.deepEqual(newDoc.arr, []);
+    assert.deepEqual(newDoc.arr2, ['foo', 'bar']);
   });
 });

From 58cfc157d1183be524ad3c4fb28b760968bcf27f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jul 2020 10:32:33 -0400
Subject: [PATCH 1111/2348] docs: correct link to transactions examples

---
 website.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/website.js b/website.js
index 6408030ccf9..6687a41e802 100644
--- a/website.js
+++ b/website.js
@@ -23,7 +23,7 @@ markdown.setOptions({
 
 const tests = [
   ...acquit.parse(fs.readFileSync('./test/geojson.test.js').toString()),
-  ...acquit.parse(fs.readFileSync('./test/docs/transactions.test.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/es-next/transactions.test.es6.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/schema.alias.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/model.middleware.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/docs/date.test.js').toString()),

From 065d549caa08d6f0722ae21b33cacad58e6f786d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jul 2020 10:39:20 -0400
Subject: [PATCH 1112/2348] feat: use mongodb driver 3.6.0

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 1f4bebeb3b5..0a05f3d089e 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "git@github.com:mongodb/node-mongodb-native.git#3.6",
+    "mongodb": "3.6.0",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From 5953a675c23adeed8d22f78dd53a2f107c02ea71 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jul 2020 11:44:37 -0400
Subject: [PATCH 1113/2348] chore: release 5.9.27

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c106837a892..1b5c85275ec 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.9.27 / 2020-07-31
+===================
+ * fix: upgrade mongodb driver -> 3.5.10 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * docs(transactions): make transactions docs use async/await for readability #9204
+
 5.9.26 / 2020-07-27
 ===================
  * fix(document): allow unsetting boolean field by setting the field to `undefined` #9275
diff --git a/package.json b/package.json
index 8df50d56ae3..65f90022a6d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.26",
+  "version": "5.9.27",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 1caa7143cfcbed78d7ce00475e2a17f0768b6107 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 31 Jul 2020 11:46:48 -0400
Subject: [PATCH 1114/2348] docs: correct filepath to transactions tests

---
 website.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/website.js b/website.js
index 6408030ccf9..6687a41e802 100644
--- a/website.js
+++ b/website.js
@@ -23,7 +23,7 @@ markdown.setOptions({
 
 const tests = [
   ...acquit.parse(fs.readFileSync('./test/geojson.test.js').toString()),
-  ...acquit.parse(fs.readFileSync('./test/docs/transactions.test.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/es-next/transactions.test.es6.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/schema.alias.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/model.middleware.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/docs/date.test.js').toString()),

From 4d8ecacf3eed1efe8445e832036c047d6a589527 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 2 Aug 2020 19:23:37 -0400
Subject: [PATCH 1115/2348] test(schema): repro #9287

---
 test/schema.string.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)
 create mode 100644 test/schema.string.test.js

diff --git a/test/schema.string.test.js b/test/schema.string.test.js
new file mode 100644
index 00000000000..16d58aade98
--- /dev/null
+++ b/test/schema.string.test.js
@@ -0,0 +1,24 @@
+'use strict';
+
+const start = require('./common');
+
+const assert = require('assert');
+
+const mongoose = start.mongoose;
+const Schema = mongoose.Schema;
+
+describe('SchemaString', function() {
+  let M;
+
+  before(function() {
+    const schema = new Schema({ x: { type: String, match: /abc/g } });
+    mongoose.deleteModel(/Test/);
+    M = mongoose.model('Test', schema);
+  });
+
+  it('works when RegExp has global flag set (gh-9287)', function() {
+    const doc = new M({ x: 'abc' });
+    assert.ifError(doc.validateSync());
+    assert.ifError(doc.validateSync());
+  });
+});

From 6f6f441d954fbd63f1c4251931f63c8015ab3f38 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 2 Aug 2020 19:24:13 -0400
Subject: [PATCH 1116/2348] fix(schema): handle `match` schema validator with
 `/g` flag

Fix #9287
---
 lib/schema/string.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/schema/string.js b/lib/schema/string.js
index 68906da81dc..746900d706c 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -516,6 +516,10 @@ SchemaString.prototype.match = function match(regExp, message) {
       return false;
     }
 
+    // In case RegExp happens to have `/g` flag set, we need to reset the
+    // `lastIndex`, otherwise `match` will intermittently fail.
+    regExp.lastIndex = 0;
+
     const ret = ((v != null && v !== '')
       ? regExp.test(v)
       : true);

From db545ff01120edf2265de161052f85ea8702bfce Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 4 Aug 2020 13:00:04 -0400
Subject: [PATCH 1117/2348] chore: update opencollective sponsors

---
 index.pug | 15 +++------------
 1 file changed, 3 insertions(+), 12 deletions(-)

diff --git a/index.pug b/index.pug
index d5a8451dd17..77955e78987 100644
--- a/index.pug
+++ b/index.pug
@@ -193,18 +193,12 @@ html(lang='en')
               <a href="https://loanscouter.com/">
                 <img class="sponsor" src="https://images.opencollective.com/lead-supply/7400b71/logo.png" style="height: 100px">
               </a>
-              <a href="https://superkredit.net/">
-                <img class="sponsor" src="https://images.opencollective.com/superkredit/6eb441d/logo.png" style="height: 100px">
-              </a>
               <a href="https://fair-laan.se/">
                 <img class="sponsor" src="https://images.opencollective.com/fair-laan-se/939304b/logo.png" style="height: 100px">
               </a>
               <a href="https://craftresumes.com/professional-resume-writer/">
                 <img class="sponsor" alt="Professional resume writer" src="https://s3.amazonaws.com/codebarbarian-images/craftresumes.png">
               </a>
-              <a href="https://domainwheel.com/">
-                <img class="sponsor" src="https://s25990.pcdn.co/wp-content/themes/namegenerator/img/logo_dw.jpg" style="height:100px">
-              </a>
               <a href="https://uiuxagencies.top/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F62223ab0-f4f7-11e8-919f-53f2ea21a967.png&height=100" style="height:100px">
               </a>
@@ -271,9 +265,6 @@ html(lang='en')
               <a href="https://taxfreesnus.com/">
                 <img class="sponsor" src="https://images.opencollective.com/taxfreesnus-com/ebf869a/logo.png" style="height: 100px">
               </a>
-              <a href="https://searchpromocodes.com/">
-                <img class="sponsor" src="https://images.opencollective.com/searchpromocodes/68ae5dd/logo/256.png" style="height: 100px">
-              </a>
               <a href="https://www.nettikasinot.org/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-org/bbd887f/logo/256.png" style="height: 100px">
               </a>
@@ -283,9 +274,6 @@ html(lang='en')
               <a href="https://www.kasinot.fi/">
                 <img class="sponsor" src="https://images.opencollective.com/kasinot-fi/e09aa2e/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.coinnewsspan.com/">
-                <img class="sponsor" src="https://images.opencollective.com/coinnewsspan/c0933b4/logo/256.png" style="height: 100px">
-              </a>
               <a href="https://mobilunity.com/">
                 <img class="sponsor" src="https://images.opencollective.com/mobilunity/e4ca372/logo/256.png" style="height: 100px">
               </a>
@@ -364,6 +352,9 @@ html(lang='en')
               <a href="https://www.polskiekasyno.com/">
                 <img class="sponsor" src="https://images.opencollective.com/polskiekasyno-com/a8975c6/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://casinohex.in/online-casinos/">
+                <img class="sponsor" src="https://images.opencollective.com/casinohex-in/0d7625b/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 2b2b3c5057f97f2399f76d8d4b0a7b22715b115d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Aug 2020 12:06:31 -0400
Subject: [PATCH 1118/2348] test(document): repro #9293

---
 test/document.test.js | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index ae3451ddd40..5236f2a5782 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9121,4 +9121,46 @@ describe('document', function() {
       assert.ok(!('a' in fromDb));
     });
   });
+
+  it('keeps manually populated paths when setting a nested path to itself (gh-9293)', function() {
+    const StepSchema = Schema({
+      ride: { type: ObjectId, ref: 'Ride' },
+      status: Number
+    });
+
+    const RideSchema = Schema({
+      status: Number,
+      steps: {
+        taxi: [{ type: ObjectId, ref: 'Step' }],
+        rent: [{ type: ObjectId, ref: 'Step' }],
+        vehicle: [{ type: ObjectId, ref: 'Step' }]
+      }
+    });
+
+    const Step = db.model('Step', StepSchema);
+    const Ride = db.model('Ride', RideSchema);
+
+    return co(function*() {
+      let ride = yield Ride.create({ status: 0 });
+      const steps = yield Step.create([
+        { ride: ride, status: 0 },
+        { ride: ride, status: 1 },
+        { ride: ride, status: 2 }
+      ]);
+
+      ride.steps = { taxi: [steps[0]], rent: [steps[1]], vehicle: [steps[2]] };
+      yield ride.save();
+
+      ride = yield Ride.findOne({}).populate('steps.taxi steps.vehicle steps.rent');
+
+      assert.equal(ride.steps.taxi[0].status, 0);
+      assert.equal(ride.steps.rent[0].status, 1);
+      assert.equal(ride.steps.vehicle[0].status, 2);
+
+      ride.steps = ride.steps;
+      assert.equal(ride.steps.taxi[0].status, 0);
+      assert.equal(ride.steps.rent[0].status, 1);
+      assert.equal(ride.steps.vehicle[0].status, 2);
+    });
+  });
 });

From 816d75b1a4ec2add7bf8c85fa0f535d0cae3a1a9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Aug 2020 12:20:24 -0400
Subject: [PATCH 1119/2348] fix(document): keepsmanually populated paths when
 setting a nested path to itself

Fix #9293
---
 lib/helpers/document/compile.js | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index cc1b49ac492..ae91183ea34 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -124,6 +124,13 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
             }
           });
 
+          Object.defineProperty(nested, '$__parent', {
+            enumerable: false,
+            configurable: true,
+            writable: false,
+            value: this
+          });
+
           compile(subprops, nested, path, options);
           this.$__.getters[path] = nested;
         }
@@ -131,8 +138,10 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
         return this.$__.getters[path];
       },
       set: function(v) {
-        if (v instanceof Document) {
-          v = v.toObject({ transform: false });
+        if (v != null && v.$__isNested) {
+          // Convert top-level to POJO, but leave subdocs hydrated so `$set`
+          // can handle them. See gh-9293.
+          v = v.$__parent.get(v.$__.nestedPath);
         }
         const doc = this.$__[scopeSymbol] || this;
         doc.$set(path, v);

From b878ba928160040aa2149c47b0c3702c19eba676 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Aug 2020 13:09:04 -0400
Subject: [PATCH 1120/2348] test(document): repro #9266

---
 test/document.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 5236f2a5782..9f106058407 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9163,4 +9163,20 @@ describe('document', function() {
       assert.equal(ride.steps.vehicle[0].status, 2);
     });
   });
+
+  it('allows saving after setting document array to itself (gh-9266)', function() {
+    const Model = db.model('Test', Schema({ keys: [{ _id: false, name: String }] }));
+
+    return co(function*() {
+      const document = new Model({});
+
+      document.keys[0] = { name: 'test' };
+      document.keys = document.keys;
+
+      yield document.save();
+
+      const fromDb = yield Model.findOne();
+      assert.deepEqual(fromDb.toObject().keys, [{ name: 'test' }]);
+    });
+  });
 });

From 91552fb0ae46aaa87071f486c4504690895be63b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Aug 2020 13:09:17 -0400
Subject: [PATCH 1121/2348] fix(document): allow saving after setting document
 array to itself

Fix #9266
---
 lib/schema/documentarray.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 122883c5ff0..5157684fdd0 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -361,6 +361,11 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
   // lazy load
   MongooseDocumentArray || (MongooseDocumentArray = require('../types/documentarray'));
 
+  // Skip casting if `value` is the same as the previous value, no need to cast. See gh-9266
+  if (value != null && value[arrayPathSymbol] != null && value === prev) {
+    return value;
+  }
+
   let selected;
   let subdoc;
   const _opts = { transform: false, virtuals: false };

From 0b89e87efc8cb6801b1ae03495b362df65266bd3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Aug 2020 14:13:35 -0400
Subject: [PATCH 1122/2348] test(error): repro #9296

---
 test/errors.validation.test.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 14d5942360e..0496b77a716 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -212,17 +212,18 @@ describe('ValidationError', function() {
     });
   });
 
-  it('JSON.stringify() with message (gh-5309)', function() {
+  it('JSON.stringify() with message (gh-5309) (gh-9296)', function() {
     model.modelName = 'TestClass';
     const err = new ValidationError(new model());
 
-    err.addError('test', { message: 'Fail' });
+    err.addError('test', new ValidatorError({ message: 'Fail' }));
 
     const obj = JSON.parse(JSON.stringify(err));
     assert.ok(obj.message.indexOf('TestClass validation failed') !== -1,
       obj.message);
     assert.ok(obj.message.indexOf('test: Fail') !== -1,
       obj.message);
+    assert.ok(obj.errors['test'].message);
 
     function model() {}
   });

From 7a47529ee3b0add965f25ed55eeaf19f20eeb6ae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 5 Aug 2020 14:14:46 -0400
Subject: [PATCH 1123/2348] fix(error): ensure `name` and `message` show up on
 individual ValidatorErrors when calling JSON.stringify() on a ValidationError

Fix #9296
---
 lib/error/validator.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/error/validator.js b/lib/error/validator.js
index 8b06375d897..f880e2b5820 100644
--- a/lib/error/validator.js
+++ b/lib/error/validator.js
@@ -38,6 +38,14 @@ class ValidatorError extends MongooseError {
   toString() {
     return this.message;
   }
+
+  /*!
+   * Ensure `name` and `message` show up in toJSON output re: gh-9296
+   */
+
+  toJSON() {
+    return Object.assign({ name: this.name, message: this.message }, this);
+  }
 }
 
 

From 7415dcea1a157a429fbfa748d651ff6d7e79c06e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 6 Aug 2020 17:59:15 -0400
Subject: [PATCH 1124/2348] fix(connection): consistently stop buffering when
 "reconnected" is emitted

Fix #9295
---
 lib/connection.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/connection.js b/lib/connection.js
index a2618c8c974..dedcbb10cec 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -704,6 +704,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
       _this.readyState = STATES.connected;
       _this.emit('reconnect');
       _this.emit('reconnected');
+      _this.onOpen();
     }
   };
 

From c95c7de0232f9e0ea1dd4c07ede5b71fea7402ee Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 7 Aug 2020 16:34:52 -0400
Subject: [PATCH 1125/2348] chore: release 5.9.28

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 1b5c85275ec..4d613b91f0a 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.9.28 / 2020-08-07
+===================
+ * fix(connection): consistently stop buffering when "reconnected" is emitted #9295
+ * fix(error): ensure `name` and `message` show up on individual ValidatorErrors when calling JSON.stringify() on a ValidationError #9296
+ * fix(document): keeps manually populated paths when setting a nested path to itself #9293
+ * fix(document): allow saving after setting document array to itself #9266
+ * fix(schema): handle `match` schema validator with `/g` flag #9287
+ * docs(guide): refactor transactions examples to async/await #9204
+
 5.9.27 / 2020-07-31
 ===================
  * fix: upgrade mongodb driver -> 3.5.10 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 65f90022a6d..01b2712f09b 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.27",
+  "version": "5.9.28",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a8063d6eb0a8265e0cbd5fe11ae4a35472170576 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 7 Aug 2020 16:52:53 -0400
Subject: [PATCH 1126/2348] fix: handle auth error when Atlas username is
 incorrect

Fix #9300
---
 lib/error/serverSelection.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index c6d1bf64f95..464abf04880 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -28,7 +28,8 @@ class MongooseServerSelectionError extends MongooseError {
     // Special message for a case that is likely due to IP whitelisting issues.
     const isAtlasWhitelistError = isAtlas(reason) &&
       allServersUnknown(reason) &&
-      err.message.indexOf('bad auth') === -1;
+      err.message.indexOf('bad auth') === -1 &&
+      err.message.indexOf('Authentication failed') === -1;
     this.message = isAtlasWhitelistError ?
       atlasMessage :
       err.message;

From d0db150f9b6a63e31b0135ba1af85f01a6efdc17 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 Aug 2020 13:27:26 -0400
Subject: [PATCH 1127/2348] test(model): repro #9303

---
 test/model.indexes.test.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 43547aff57e..585b14d0309 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -581,6 +581,35 @@ describe('model', function() {
       });
     });
 
+    it('reports syncIndexes() error (gh-9303)', function() {
+      return co(function*() {
+        let userSchema = new mongoose.Schema({ username: String, email: String });
+        let User = db.model('User', userSchema);
+
+        yield User.createCollection().catch(() => {});
+        let indexes = yield User.listIndexes();
+        assert.equal(indexes.length, 1);
+
+        yield User.create([{ username: 'test', email: 'foo@bar' }, { username: 'test', email: 'foo@bar' }]);
+
+        userSchema = new mongoose.Schema({ username: String, email: String }, { autoIndex: false });
+        userSchema.index({ username: 1 }, { unique: true });
+        userSchema.index({ email: 1 });
+        db.deleteModel('User');
+        User = db.model('User', userSchema, 'User');
+
+        const err = yield User.syncIndexes().then(() => null, err => err);
+        assert.ok(err);
+        assert.equal(err.code, 11000);
+
+        indexes = yield User.listIndexes();
+        assert.equal(indexes.length, 2);
+        assert.deepEqual(indexes[1].key, { email: 1 });
+
+        yield User.collection.drop();
+      });
+    });
+
     it('cleanIndexes (gh-6676)', function() {
       return co(function*() {
         let M = db.model('Test', new Schema({

From c90c89e8780fa5d8ca915db02806af0459bd8306 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 Aug 2020 13:29:47 -0400
Subject: [PATCH 1128/2348] fix(model): make `syncIndexes()` report error if it
 can't create an index

Fix #9303
---
 lib/model.js               | 2 +-
 test/model.indexes.test.js | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 8484a0a4c9e..da0c601aee1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1568,7 +1568,7 @@ function _ensureIndexes(model, options, callback) {
       model.emit('error', err);
     }
     model.emit('index', err || indexError);
-    callback && callback(err);
+    callback && callback(err || indexError);
   };
 
   for (const index of indexes) {
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 585b14d0309..cb6f3993e9b 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -558,7 +558,7 @@ describe('model', function() {
         assert.deepEqual(indexes[1].key, { username: 1 });
         assert.ok(!indexes[1].collation);
 
-        userSchema = new mongoose.Schema({ username: String });
+        userSchema = new mongoose.Schema({ username: String }, { autoIndex: false });
         userSchema.index({ username: 1 }, {
           unique: true,
           collation: {
@@ -569,7 +569,6 @@ describe('model', function() {
         db.deleteModel('User');
         User = db.model('User', userSchema, 'User');
 
-        yield User.init();
         yield User.syncIndexes();
 
         indexes = yield User.listIndexes();

From 6d2eaefe9454545bc50fb46ad749578fc4bd8c37 Mon Sep 17 00:00:00 2001
From: Glyphack <sh.hooshyari@gmail.com>
Date: Wed, 12 Aug 2020 07:42:53 -0400
Subject: [PATCH 1129/2348] Fix link to pull

---
 lib/types/core_array.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 29f03859d81..423933f42b7 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -703,7 +703,7 @@ class CoreMongooseArray extends Array {
   }
 
   /**
-   * Alias of [pull](#types_array_MongooseArray-pull)
+   * Alias of [pull](#mongoosearray_MongooseArray-pull)
    *
    * @see MongooseArray#pull #types_array_MongooseArray-pull
    * @see mongodb http://www.mongodb.org/display/DOCS/Updating/#Updating-%24pull
@@ -955,4 +955,4 @@ function _checkManualPopulation(arr, docs) {
   }
 }
 
-module.exports = CoreMongooseArray;
\ No newline at end of file
+module.exports = CoreMongooseArray;

From c071e5275dfa0d6041cc0cad7891d2875059a992 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Aug 2020 14:47:19 -0400
Subject: [PATCH 1130/2348] fix(document): support setting nested path to
 itself when it has nested subpaths

Fix #9313
---
 lib/helpers/document/compile.js |  2 +-
 test/document.test.js           | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index ae91183ea34..0868f24516c 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -141,7 +141,7 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
         if (v != null && v.$__isNested) {
           // Convert top-level to POJO, but leave subdocs hydrated so `$set`
           // can handle them. See gh-9293.
-          v = v.$__parent.get(v.$__.nestedPath);
+          v = v.$__parent.get(path);
         }
         const doc = this.$__[scopeSymbol] || this;
         doc.$set(path, v);
diff --git a/test/document.test.js b/test/document.test.js
index 9f106058407..864e53c63f3 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9164,6 +9164,39 @@ describe('document', function() {
     });
   });
 
+  it('doesnt wipe out nested paths when setting a nested path to itself (gh-9313)', function() {
+    const schema = new Schema({
+      nested: {
+        prop1: { type: Number, default: 50 },
+        prop2: {
+          type: String,
+          enum: ['val1', 'val2'],
+          default: 'val1',
+          required: true
+        },
+        prop3: {
+          prop4: { type: Number, default: 0 }
+        }
+      }
+    });
+
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      let doc = yield Model.create({});
+
+      doc = yield Model.findById(doc);
+
+      doc.nested = doc.nested;
+
+      assert.equal(doc.nested.prop2, 'val1');
+      yield doc.save();
+
+      const fromDb = yield Model.collection.findOne({ _id: doc._id });
+      assert.equal(fromDb.nested.prop2, 'val1');
+    });
+  });
+
   it('allows saving after setting document array to itself (gh-9266)', function() {
     const Model = db.model('Test', Schema({ keys: [{ _id: false, name: String }] }));
 

From 4f833ff15dc78c49e15ef2ae841063fbc05a868c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 Aug 2020 15:06:41 -0400
Subject: [PATCH 1131/2348] chore: release 5.9.29

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 4d613b91f0a..f838a47b330 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.9.29 / 2020-08-13
+===================
+ * fix(document): support setting nested path to itself when it has nested subpaths #9313
+ * fix(model): make `syncIndexes()` report error if it can't create an index #9303
+ * fix: handle auth error when Atlas username is incorrect #9300
+
 5.9.28 / 2020-08-07
 ===================
  * fix(connection): consistently stop buffering when "reconnected" is emitted #9295
diff --git a/package.json b/package.json
index 01b2712f09b..b20b2b479db 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.28",
+  "version": "5.9.29",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From d374f141f395066b0f60c9a49ccdbdc408e78191 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Aug 2020 11:19:29 -0400
Subject: [PATCH 1132/2348] fix: work around
 https://jira.mongodb.org/projects/NODE/issues/NODE-2741

Re: #9188
---
 lib/helpers/model/castBulkWrite.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 0455562f461..8e47afce706 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -71,7 +71,6 @@ module.exports = function castBulkWrite(originalModel, op, options) {
           overwrite: false,
           upsert: op['updateOne'].upsert
         });
-
       } catch (error) {
         return callback(error, null);
       }
@@ -152,6 +151,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
         if (error) {
           return callback(error, null);
         }
+        op['replaceOne']['replacement'] = op['replaceOne']['replacement'].toBSON();
         callback(null);
       });
     };

From bd455c440584c0a8e332b627cba812bcabdbfbc3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Aug 2020 11:29:56 -0400
Subject: [PATCH 1133/2348] fix(update): allow upsert with empty updates

Re: #9188
Re: mongodb/node-mongodb-native#2490
---
 lib/helpers/model/castBulkWrite.js | 16 ++++++++++++----
 lib/helpers/query/castUpdate.js    |  6 ++++++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 8e47afce706..619281285e9 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -37,8 +37,12 @@ module.exports = function castBulkWrite(originalModel, op, options) {
   } else if (op['updateOne']) {
     return (callback) => {
       try {
-        if (!op['updateOne']['filter']) throw new Error('Must provide a filter object.');
-        if (!op['updateOne']['update']) throw new Error('Must provide an update object.');
+        if (!op['updateOne']['filter']) {
+          throw new Error('Must provide a filter object.');
+        }
+        if (!op['updateOne']['update']) {
+          throw new Error('Must provide an update object.');
+        }
 
         const model = decideModelByObject(originalModel, op['updateOne']['filter']);
         const schema = model.schema;
@@ -80,8 +84,12 @@ module.exports = function castBulkWrite(originalModel, op, options) {
   } else if (op['updateMany']) {
     return (callback) => {
       try {
-        if (!op['updateMany']['filter']) throw new Error('Must provide a filter object.');
-        if (!op['updateMany']['update']) throw new Error('Must provide an update object.');
+        if (!op['updateMany']['filter']) {
+          throw new Error('Must provide a filter object.');
+        }
+        if (!op['updateMany']['update']) {
+          throw new Error('Must provide an update object.');
+        }
 
         const model = decideModelByObject(originalModel, op['updateMany']['filter']);
         const schema = model.schema;
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 327d9d2f862..6009852fdd8 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -105,6 +105,12 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
     }
   }
 
+  if (Object.keys(ret).length === 0 && options.upsert) {
+    // Trick the driver into allowing empty upserts to work around
+    // https://github.com/mongodb/node-mongodb-native/pull/2490
+    return { $fake: true, toBSON: () => ({}) };
+  }
+
   return ret;
 };
 

From 7646d9e3cb6e4359d30d3db65d99079c0cb63d83 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Aug 2020 11:54:29 -0400
Subject: [PATCH 1134/2348] fix: alternative fix for allowing empty update on
 upsert

Fix #9188
---
 lib/helpers/model/castBulkWrite.js | 4 ++--
 lib/helpers/query/castUpdate.js    | 6 ++++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 619281285e9..6e7a8300754 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -74,7 +74,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
           strict: strict,
           overwrite: false,
           upsert: op['updateOne'].upsert
-        });
+        }, model, op['updateOne']['filter']);
       } catch (error) {
         return callback(error, null);
       }
@@ -121,7 +121,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
           strict: strict,
           overwrite: false,
           upsert: op['updateMany'].upsert
-        });
+        }, model, op['updateMany']['filter']);
 
       } catch (error) {
         return callback(error, null);
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 6009852fdd8..8afd60af8f7 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -105,10 +105,12 @@ module.exports = function castUpdate(schema, obj, options, context, filter) {
     }
   }
 
-  if (Object.keys(ret).length === 0 && options.upsert) {
+  if (Object.keys(ret).length === 0 &&
+      options.upsert &&
+      Object.keys(filter).length > 0) {
     // Trick the driver into allowing empty upserts to work around
     // https://github.com/mongodb/node-mongodb-native/pull/2490
-    return { $fake: true, toBSON: () => ({}) };
+    return { $setOnInsert: filter };
   }
 
   return ret;

From 25cdb958aa92e5fe2e998cb437393dbca5c613ca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 Aug 2020 12:41:03 -0400
Subject: [PATCH 1135/2348] chore: release 5.10.0

---
 History.md   | 20 ++++++++++++++++++++
 package.json |  2 +-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f838a47b330..8a6df985ded 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,23 @@
+5.10.0 / 2020-08-14
+===================
+ * feat: upgrade to MongoDB driver 3.6 for full MongoDB 4.4 support
+ * feat(connection): add `Connection#transaction()` helper that handles resetting Mongoose document state if the transaction fails #8380
+ * feat(connection): make transaction() helper reset array atomics after failed transaction
+ * feat(schema+model): add `optimisticConcurrency` option to use OCC for `save()` #9001 #5424
+ * feat(aggregate): add `Aggregate#search()` for Atlas Text Search #9115
+ * feat(mongoose): add support for setting `setDefaultsOnInsert` as a global option #9036 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(mongoose): add support for setting `returnOriginal` as a global option #9189 #9183 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(mongoose): allow global option mongoose.set('strictQuery', true) #9016 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(document): add Document#getChanges #9097 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(document): support `defaults` option to disable adding defaults to a single document #8271
+ * feat(SingleNestedPath+DocumentArray): add static `set()` function for global options, support setting `_id` globally #8883
+ * feat(query): handle casting `$or` when each clause contains a different discriminator key #9018
+ * feat(query): add overwriteDiscriminatorKey option that allows changing the discriminator key in `findOneAndUpdate()`, `updateOne()`, etc. #6087
+ * fix(connection): make calling `mongoose.connect()` while already connected a no-op #9203
+ * feat(connection): add `getClient()` and `setClient()` function for interacting with a connection's underlying MongoClient instance #9164
+ * feat(document+populate): add `parent()` function that allows you to get the parent document for populated docs #8092
+ * feat(document): add `useProjection` option to `toObject()` and `toJSON()` for hiding deselected fields on newly created documents #9118
+
 5.9.29 / 2020-08-13
 ===================
  * fix(document): support setting nested path to itself when it has nested subpaths #9313
diff --git a/package.json b/package.json
index 28eba65c88c..32c3ad5d074 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.9.29",
+  "version": "5.10.0",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 49057fa13ce82342cb87a344f58406739423b99d Mon Sep 17 00:00:00 2001
From: moander <moander@outlook.com>
Date: Sun, 16 Aug 2020 01:21:55 +0200
Subject: [PATCH 1136/2348] Updated connect example to avoid deprecation
 warnings

---
 README.md | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index e6e3914f702..0da1d48835c 100644
--- a/README.md
+++ b/README.md
@@ -72,7 +72,9 @@ Both `connect` and `createConnection` take a `mongodb://` URI, or the parameters
 ```js
 await mongoose.connect('mongodb://localhost/my_database', {
   useNewUrlParser: true,
-  useUnifiedTopology: true
+  useUnifiedTopology: true,
+  useFindAndModify: false,
+  useCreateIndex: true
 });
 ```
 

From 08a30c7eaf6e7ce216b1ad5a7b8394587609cd91 Mon Sep 17 00:00:00 2001
From: Felix Reinhardt <felixre0@users.noreply.github.com>
Date: Mon, 17 Aug 2020 16:19:20 +0200
Subject: [PATCH 1137/2348] Fix: Retaining null value for populated documents
 when _id is suppressed

---
 lib/helpers/populate/assignVals.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 798482197db..c47172b0b25 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -243,7 +243,7 @@ function valueFilter(val, assignmentOpts, populateOptions) {
  */
 
 function maybeRemoveId(subdoc, assignmentOpts) {
-  if (assignmentOpts.excludeId) {
+  if (subdoc != null && assignmentOpts.excludeId) {
     if (typeof subdoc.$__setValue === 'function') {
       delete subdoc._doc._id;
     } else {

From bf1a9b492a986221f441f7276f9c944a2d733828 Mon Sep 17 00:00:00 2001
From: Felix Reinhardt <felixre0@users.noreply.github.com>
Date: Mon, 17 Aug 2020 17:10:41 +0200
Subject: [PATCH 1138/2348] Add regression test for Issue #9336

---
 test/model.populate.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index ecf2a52e33e..f9055597a40 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -1626,6 +1626,33 @@ describe('model: populate:', function() {
     });
   });
 
+  it('supports `retainNullValues` while supressing _id of subdocument', function() {
+    const BlogPost = db.model('BlogPost', blogPostSchema);
+    const User = db.model('User', userSchema);
+
+    return co(function*() {
+      const user = new User({ name: 'Victor Hugo' });
+      yield user.save();
+      const post = yield BlogPost.create({
+        title: 'Notre-Dame de Paris',
+        fans: []
+      });
+      
+      yield BlogPost.collection.updateOne({ _id: post._id }, {
+        $set: { fans: [user.id] }
+      });
+
+      yield user.delete()
+
+      const returned = yield BlogPost.
+        findById(post._id).
+        populate({ path: 'fans', select: 'name -_id', options: { retainNullValues: true } });
+
+      assert.equal(returned.fans.length, 1);
+      assert.strictEqual(returned.fans[0], null);
+    });
+  });
+
   it('populating more than one array at a time', function(done) {
     const User = db.model('User', userSchema);
     const M = db.model('Test', new Schema({

From 01b48b5d3419fab07624f23bffe72cdf1e8db678 Mon Sep 17 00:00:00 2001
From: Felix Reinhardt <felixre0@users.noreply.github.com>
Date: Mon, 17 Aug 2020 17:27:32 +0200
Subject: [PATCH 1139/2348] Fixed code style

---
 test/model.populate.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index f9055597a40..3fdd83c76ee 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -1637,12 +1637,12 @@ describe('model: populate:', function() {
         title: 'Notre-Dame de Paris',
         fans: []
       });
-      
+
       yield BlogPost.collection.updateOne({ _id: post._id }, {
         $set: { fans: [user.id] }
       });
 
-      yield user.delete()
+      yield user.delete();
 
       const returned = yield BlogPost.
         findById(post._id).

From 19a7eb4c07d5478236fed43faaaffe6fe9061034 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 Aug 2020 10:10:58 -0400
Subject: [PATCH 1140/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 77955e78987..371020ede87 100644
--- a/index.pug
+++ b/index.pug
@@ -355,6 +355,9 @@ html(lang='en')
               <a href="https://casinohex.in/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-in/0d7625b/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://www.baocasino.com/">
+                <img class="sponsor" src="https://images.opencollective.com/baocasino/b5a71c4/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 1256d77da5a147679f80ddd2c01ac7b44068ecae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 Aug 2020 14:17:24 -0400
Subject: [PATCH 1141/2348] docs: add note about using `ref` as function

---
 lib/schematype.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index 938a376c48b..82dd98ef568 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -960,8 +960,10 @@ SchemaType.prototype.required = function(required, message) {
  *     const User = mongoose.model('User', userSchema);
  *
  *     const postSchema = new Schema({ user: mongoose.ObjectId });
- *     postSchema.path('user').ref('User'); // By model name
- *     postSchema.path('user').ref(User); // Can pass the model as well
+ *     postSchema.path('user').ref('User'); // Can set ref to a model name
+ *     postSchema.path('user').ref(User); // Or a model class
+ *     postSchema.path('user').ref(() => 'User'); // Or a function that returns the model name
+ *     postSchema.path('user').ref(() => User); // Or a function that returns the model class
  *
  *     // Or you can just declare the `ref` inline in your schema
  *     const postSchema2 = new Schema({

From a63b61104e910d83d26ac1a114f02eb1d0607636 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 22 Aug 2020 18:26:11 -0400
Subject: [PATCH 1142/2348] docs(model): use createIndex correctly

Fix #9339
---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 00efe95f740..0a1f01c0904 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1342,7 +1342,7 @@ Model.createCollection = function createCollection(options, callback) {
  *
  *     const schema = new Schema({ name: { type: String, unique: true } });
  *     const Customer = mongoose.model('Customer', schema);
- *     await Customer.createIndex({ age: 1 }); // Index is not in schema
+ *     await Customer.collection.createIndex({ age: 1 }); // Index is not in schema
  *     // Will drop the 'age' index and create an index on `name`
  *     await Customer.syncIndexes();
  *

From 56fb748282cc66cf54c9ad58b4ef5b017fe27495 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 23 Aug 2020 15:44:43 -0400
Subject: [PATCH 1143/2348] test: repro #9350

---
 test/model.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 6fcfb2ca6f2..9d0e705e4da 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6869,6 +6869,23 @@ describe('Model', function() {
     });
   });
 
+  it('allows calling `create()` after `bulkWrite()` (gh-9350)', function() {
+    const schema = Schema({ foo: Boolean });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      yield Model.bulkWrite([
+        { insertOne: { document: { foo: undefined } } },
+        { updateOne: { filter: {}, update: { $set: { foo: true } } } }
+      ]);
+
+      yield Model.create({ foo: undefined });
+
+      const docs = yield Model.find();
+      assert.equal(docs.length, 2);
+    });
+  });
+
   describe('returnOriginal (gh-9183)', function() {
     const originalValue = mongoose.get('returnOriginal');
     beforeEach(() => {

From 0bdac75eb62f78e3d953c584872a5dc4f1a2489a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 23 Aug 2020 15:44:55 -0400
Subject: [PATCH 1144/2348] fix: allow calling `create()` after `bulkWrite()`
 by clearing internal casting context

Fix #9350
---
 lib/schema/boolean.js |  5 ++++-
 lib/schematype.js     | 13 ++++++++++---
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index 37b4d51e0a0..c2640841cf1 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -230,7 +230,10 @@ SchemaBoolean.prototype.castForQuery = function($conditional, val) {
  */
 
 SchemaBoolean.prototype._castNullish = function _castNullish(v) {
-  if (typeof v === 'undefined' && this.$$context != null && this.$$context._mongooseOptions.omitUndefined) {
+  if (typeof v === 'undefined' &&
+      this.$$context != null &&
+      this.$$context._mongooseOptions != null &&
+      this.$$context._mongooseOptions.omitUndefined) {
     return v;
   }
   const castBoolean = typeof this.constructor.cast === 'function' ?
diff --git a/lib/schematype.js b/lib/schematype.js
index 82dd98ef568..38a3d3dbe8c 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1461,12 +1461,19 @@ SchemaType.prototype.$conditionalHandlers = {
 SchemaType.prototype.castForQueryWrapper = function(params) {
   this.$$context = params.context;
   if ('$conditional' in params) {
-    return this.castForQuery(params.$conditional, params.val);
+    const ret = this.castForQuery(params.$conditional, params.val);
+    this.$$context = null;
+    return ret;
   }
   if (params.$skipQueryCastForUpdate || params.$applySetters) {
-    return this._castForQuery(params.val);
+    const ret = this._castForQuery(params.val);
+    this.$$context = null;
+    return ret;
   }
-  return this.castForQuery(params.val);
+
+  const ret = this.castForQuery(params.val);
+  this.$$context = null;
+  return ret;
 };
 
 /**

From ae5d739adf45e6c2506fac0e60b2809e52446e92 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 24 Aug 2020 17:44:40 -0400
Subject: [PATCH 1145/2348] test(document): repro #9351

---
 test/document.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index b05fe9f98c1..6d5bb42fc8c 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9270,4 +9270,20 @@ describe('document', function() {
       assert.deepEqual(fromDb.toObject().keys, [{ name: 'test' }]);
     });
   });
+
+  it('allows accessing document values from function default on array (gh-9351) (gh-6155)', function() {
+    const schema = Schema({
+      publisher: String,
+      authors: {
+        type: [String],
+        default: function() {
+          return [this.publisher];
+        }
+      }
+    });
+    const Test = db.model('Test', schema);
+
+    const doc = new Test({ publisher: 'Mastering JS' });
+    assert.deepEqual(doc.toObject().authors, ['Mastering JS']);
+  });
 });

From 0b46829e9ba8952e09d6c57b431de422b6f66644 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 24 Aug 2020 17:44:49 -0400
Subject: [PATCH 1146/2348] fix(document): allow accessing document values from
 function `default` on array

Fix #9351
---
 lib/schema/array.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 8323ce4dd8b..a0bd356d4e2 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -116,7 +116,7 @@ function SchemaArray(key, cast, options, schemaOptions) {
       // Leave it up to `cast()` to convert the array
       return arr;
     };
-    defaultFn.$runBeforeSetters = true;
+    defaultFn.$runBeforeSetters = !fn;
     this.default(defaultFn);
   }
 }

From d56059a91fb2c0dc59734dda2209f80881ab95eb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 25 Aug 2020 15:33:05 -0400
Subject: [PATCH 1147/2348] test(model): repro #9316

---
 test/model.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 9d0e705e4da..e68f95edcc7 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6886,6 +6886,20 @@ describe('Model', function() {
     });
   });
 
+  it('skips applying init hooks if `document` option set to `false` (gh-9316)', function() {
+    const schema = new Schema({ name: String });
+    let called = 0;
+    schema.post(/.*/, { query: true, document: false }, function test() {
+      ++called;
+    });
+
+    const Model = db.model('Test', schema);
+
+    const doc = new Model();
+    doc.init({ name: 'test' });
+    assert.equal(called, 0);
+  });
+
   describe('returnOriginal (gh-9183)', function() {
     const originalValue = mongoose.get('returnOriginal');
     beforeEach(() => {

From 0b8c6a1323aaad04e2863f301bda7d42b2d1b6ac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 25 Aug 2020 15:33:13 -0400
Subject: [PATCH 1148/2348] fix(model): skip applying init hook if called with
 `schema.pre(..., { document: false })`

Fix #9316
---
 lib/helpers/model/applyHooks.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index de45f96a322..9570a368e79 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -75,7 +75,7 @@ function applyHooks(model, schema, options) {
       if (hook.name === 'updateOne' || hook.name === 'deleteOne') {
         return !!hook['document'];
       }
-      if (hook.name === 'remove') {
+      if (hook.name === 'remove' || hook.name === 'init') {
         return hook['document'] == null || !!hook['document'];
       }
       return true;

From fadc813eaa32dd357e93beb8614de35e5f346600 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 25 Aug 2020 20:10:47 -0400
Subject: [PATCH 1149/2348] fix(mongoose): fix `.then()` is not a function
 error when calling `mongoose.connect()` multiple times

Fix #9358
Fix #9335
Fix #9331
---
 lib/connection.js |  2 +-
 lib/index.js      | 10 +++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index f55570b4145..106103ce01e 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -785,7 +785,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
   const promise = new Promise((resolve, reject) => {
     const client = new mongodb.MongoClient(uri, options);
     _this.client = client;
-    client.connect(function(error) {
+    client.connect((error) => {
       if (error) {
         _this.readyState = STATES.disconnected;
         return reject(error);
diff --git a/lib/index.js b/lib/index.js
index 0fa9f2d7567..5ac7c9a949e 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -336,7 +336,15 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
 Mongoose.prototype.connect = function(uri, options, callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
   const conn = _mongoose.connection;
-  return conn.openUri(uri, options, callback).then(() => _mongoose);
+
+  return promiseOrCallback(callback, cb => {
+    conn.openUri(uri, options, err => {
+      if (err != null) {
+        return cb(err);
+      }
+      return cb(null, _mongoose);
+    });
+  });
 };
 
 /**

From 66ba2ecd54c63b3e115f03a6f90bf0d812e3dc9c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 25 Aug 2020 20:50:13 -0400
Subject: [PATCH 1150/2348] test(populate): repro #9340

---
 test/model.populate.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 3fdd83c76ee..7600736d316 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9649,4 +9649,32 @@ describe('model: populate:', function() {
       assert.deepEqual(notifications.map(el => el.subject.name), ['Keanu', 'Bud']);
     });
   });
+
+  it('skips checking `refPath` if the path to populate is undefined (gh-9340)', function() {
+    const firstSchema = Schema({
+      ref: String,
+      linkedId: {
+        type: Schema.ObjectId,
+        refPath: 'ref'
+      }
+    });
+    const Parent = db.model('Parent', firstSchema);
+
+    const secondSchema = new Schema({ name: String });
+    const Child = db.model('Child', secondSchema);
+
+    return co(function*() {
+      const child = yield Child.create({ name: 'child' });
+      yield Parent.create({ ref: 'Child', linkedId: child._id });
+      yield Parent.create({ ref: 'does not exist' });
+
+      const res = yield Parent.find().populate('linkedId').sort({ ref: 1 }).exec();
+      assert.equal(res.length, 2);
+
+      assert.equal(res[0].ref, 'Child');
+      assert.equal(res[0].linkedId.name, 'child');
+      assert.equal(res[1].ref, 'does not exist');
+      assert.strictEqual(res[1].linkedId, undefined);
+    });
+  });
 });

From 1e76f7086b882a8457c39cd52dd59d32bc9d853a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 25 Aug 2020 20:50:32 -0400
Subject: [PATCH 1151/2348] fix(populate): skip checking `refPath` if the path
 to populate is undefined

Fix #9340
---
 lib/helpers/populate/getModelsMapForPopulate.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index c1f082caa07..0498fc1aa74 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -282,7 +282,12 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
           originalModel :
           modelName[modelSymbol] ? modelName : connection.model(modelName);
       } catch (error) {
-        return error;
+        // If `ret` is undefined, we'll add an empty entry to modelsMap. We shouldn't
+        // execute a query, but it is necessary to make sure `justOne` gets handled
+        // correctly for setting an empty array (see gh-8455)
+        if (ret !== undefined) {
+          return error;
+        }
       }
 
       let ids = ret;

From 1b416bbc0266302c61b4c616c69b8d4fe93e9c22 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 26 Aug 2020 12:21:28 -0400
Subject: [PATCH 1152/2348] test(model): repro #9327

---
 test/model.test.js | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index e68f95edcc7..d703a07dc6e 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6900,6 +6900,50 @@ describe('Model', function() {
     assert.equal(called, 0);
   });
 
+  it('retains atomics after failed `save()` (gh-9327)', function() {
+    const schema = new Schema({ arr: [String] });
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield Test.create({ arr: [] });
+
+      yield Test.deleteMany({});
+
+      doc.arr.push('test');
+      const err = yield doc.save().then(() => null, err => err);
+      assert.ok(err);
+
+      const delta = doc.getChanges();
+      assert.ok(delta.$push);
+      assert.ok(delta.$push.arr);
+    });
+  });
+
+  it('doesnt wipe out changes made while `save()` is in flight (gh-9327)', function() {
+    const schema = new Schema({ num1: Number, num2: Number });
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield Test.create({});
+
+      doc.num1 = 1;
+      doc.num2 = 1;
+      const p = doc.save();
+
+      yield cb => setTimeout(cb, 0);
+
+      doc.num1 = 2;
+      doc.num2 = 2;
+      yield p;
+
+      yield doc.save();
+
+      const fromDb = yield Test.findById(doc._id);
+      assert.equal(fromDb.num1, 2);
+      assert.equal(fromDb.num2, 2);
+    });
+  });
+
   describe('returnOriginal (gh-9183)', function() {
     const originalValue = mongoose.get('returnOriginal');
     beforeEach(() => {

From 5629faccb40177a4102408567c085a75b96aee92 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 26 Aug 2020 12:21:39 -0400
Subject: [PATCH 1153/2348] fix(model): dont wipe out changes made while
 `save()` is in-flight

Fix #9327
---
 lib/document.js | 39 +++++++++++++++++++++++++++++++++++++++
 lib/model.js    | 24 +++++++++++++++---------
 2 files changed, 54 insertions(+), 9 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 57060f507d5..7598bdea93f 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -38,6 +38,7 @@ const clone = utils.clone;
 const deepEqual = utils.deepEqual;
 const isMongooseObject = utils.isMongooseObject;
 
+const arrayAtomicsBackupSymbol = Symbol('mongoose.Array#atomicsBackup');
 const arrayAtomicsSymbol = require('./helpers/symbols').arrayAtomicsSymbol;
 const documentArrayParent = require('./helpers/symbols').documentArrayParent;
 const documentSchemaSymbol = require('./helpers/symbols').documentSchemaSymbol;
@@ -2764,6 +2765,7 @@ Document.prototype.$__reset = function reset() {
 
       _this.$__.activePaths.init(array.$path());
 
+      array[arrayAtomicsBackupSymbol] = array[arrayAtomicsSymbol];
       array[arrayAtomicsSymbol] = {};
     });
 
@@ -2784,10 +2786,19 @@ Document.prototype.$__reset = function reset() {
     const type = dirt.value;
 
     if (type && type[arrayAtomicsSymbol]) {
+      type[arrayAtomicsBackupSymbol] = type[arrayAtomicsSymbol];
       type[arrayAtomicsSymbol] = {};
     }
   });
 
+  this.$__.backup = {};
+  this.$__.backup.activePaths = {
+    modify: Object.assign({}, this.$__.activePaths.states.modify),
+    default: Object.assign({}, this.$__.activePaths.states.default)
+  };
+  this.$__.backup.validationError = this.$__.validationError;
+  this.$__.backup.errors = this.errors;
+
   // Clear 'dirty' cache
   this.$__.activePaths.clear('modify');
   this.$__.activePaths.clear('default');
@@ -2801,6 +2812,34 @@ Document.prototype.$__reset = function reset() {
   return this;
 };
 
+/*!
+ * ignore
+ */
+
+Document.prototype.$__undoReset = function $__undoReset() {
+  if (this.$__.backup == null || this.$__.backup.activePaths == null) {
+    return;
+  }
+
+  this.$__.activePaths.states.modify = this.$__.backup.activePaths.modify;
+  this.$__.activePaths.states.default = this.$__.backup.activePaths.default;
+
+  this.$__.validationError = this.$__.backup.validationError;
+  this.errors = this.$__.backup.errors;
+
+  for (const dirt of this.$__dirty()) {
+    const type = dirt.value;
+
+    if (type && type[arrayAtomicsSymbol] && type[arrayAtomicsBackupSymbol]) {
+      type[arrayAtomicsSymbol] = type[arrayAtomicsBackupSymbol];
+    }
+  }
+
+  for (const subdoc of this.$__getAllSubdocs()) {
+    subdoc.$__undoReset();
+  }
+};
+
 /**
  * Returns this documents dirty paths / vals.
  *
diff --git a/lib/model.js b/lib/model.js
index 0a1f01c0904..4ce3e39e648 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -282,6 +282,7 @@ Model.prototype.$__handleSave = function(options, callback) {
 
       callback(null, ret);
     });
+
     this.$__reset();
     _setIsNew(this, false);
     // Make it possible to retry the insert
@@ -307,8 +308,10 @@ Model.prototype.$__handleSave = function(options, callback) {
 
       _applyCustomWhere(this, where);
 
-      this[modelCollectionSymbol].updateOne(where, delta[1], saveOptions, function(err, ret) {
+      this[modelCollectionSymbol].updateOne(where, delta[1], saveOptions, (err, ret) => {
         if (err) {
+          this.$__undoReset();
+
           callback(err);
           return;
         }
@@ -319,15 +322,21 @@ Model.prototype.$__handleSave = function(options, callback) {
       const optionsWithCustomValues = Object.assign({}, options, saveOptions);
       this.constructor.exists(this.$__where(), optionsWithCustomValues)
         .then((documentExists) => {
-          if (!documentExists) throw new DocumentNotFoundError(this.$__where(), this.constructor.modelName);
+          if (!documentExists) {
+            throw new DocumentNotFoundError(this.$__where(), this.constructor.modelName);
+          }
 
-          this.$__reset();
           callback();
         })
         .catch(callback);
       return;
     }
 
+    // store the modified paths before the document is reset
+    this.$__.modifiedPaths = this.modifiedPaths();
+
+    this.$__reset();
+
     _setIsNew(this, false);
   }
 };
@@ -345,11 +354,6 @@ Model.prototype.$__save = function(options, callback) {
       });
     }
 
-    // store the modified paths before the document is reset
-    const modifiedPaths = this.modifiedPaths();
-
-    this.$__reset();
-
     let numAffected = 0;
     if (get(options, 'safe.w') !== 0 && get(options, 'w') !== 0) {
       // Skip checking if write succeeded if writeConcern is set to
@@ -376,8 +380,9 @@ Model.prototype.$__save = function(options, callback) {
 
         if (numAffected <= 0) {
           // the update failed. pass an error back
+          this.$__undoReset();
           const err = this.$__.$versionError ||
-            new VersionError(this, version, modifiedPaths);
+            new VersionError(this, version, this.$__.modifiedPaths);
           return callback(err);
         }
 
@@ -388,6 +393,7 @@ Model.prototype.$__save = function(options, callback) {
       }
 
       if (result != null && numAffected <= 0) {
+        this.$__undoReset();
         error = new DocumentNotFoundError(result.$where,
           this.constructor.modelName, numAffected, result);
         return hooks.execPost('save:error', this, [this], { error: error }, (error) => {

From 6ec173b0a649cf723798ae1dfc0ab6b8e64d7d73 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 26 Aug 2020 15:27:00 -0400
Subject: [PATCH 1154/2348] chore: release 5.10.1

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 8a6df985ded..2ec5349ebed 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.10.1 / 2020-08-26
+===================
+ * fix(mongoose): fix `.then()` is not a function error when calling `mongoose.connect()` multiple times #9358 #9335 #9331
+ * fix: allow calling `create()` after `bulkWrite()` by clearing internal casting context #9350
+ * fix(model): dont wipe out changes made while `save()` is in-flight #9327
+ * fix(populate): skip checking `refPath` if the path to populate is undefined #9340
+ * fix(document): allow accessing document values from function `default` on array #9351
+ * fix(model): skip applying init hook if called with `schema.pre(..., { document: false })` #9316
+ * fix(populate): support `retainNullValues` when setting `_id` to `false` for subdocument #9337 #9336 [FelixRe0](https://github.com/FelixRe0)
+ * docs: update connect example to avoid deprecation warnings #9332 [moander](https://github.com/moander)
+
 5.10.0 / 2020-08-14
 ===================
  * feat: upgrade to MongoDB driver 3.6 for full MongoDB 4.4 support
diff --git a/package.json b/package.json
index 32c3ad5d074..a0ced576dd1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.0",
+  "version": "5.10.1",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 54ed4712ce21a503bbb2395e593a262b18f94fe2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 26 Aug 2020 15:58:09 -0400
Subject: [PATCH 1155/2348] docs(plugins): note that plugins should be applied
 before you call `mongoose.model()`

Fix #7723
---
 docs/plugins.pug | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/docs/plugins.pug b/docs/plugins.pug
index 8ccbd317528..0c8208740c2 100644
--- a/docs/plugins.pug
+++ b/docs/plugins.pug
@@ -27,6 +27,7 @@ block content
     <ul class="toc">
       <li><a href="#example">Example</a></li>
       <li><a href="#global">Global Plugins</a></li>
+      <li><a href="#apply-plugins-before-compiling-models">Apply Plugins Before Compiling Models</a></li>
       <li><a href="#official">Officially Supported Plugins</a></li>
     </ul>
 
@@ -84,6 +85,39 @@ block content
     const Player = mongoose.model('Player', playerSchema);
     ```
 
+    <h3 id="apply-plugins-before-compiling-models"><a href="#apply-plugins-before-compiling-models">Apply Plugins Before Compiling Models</a></h3>
+
+    Because many plugins rely on [middleware](/docs/middleware.html), you should make sure to apply plugins **before**
+    you call `mongoose.model()` or `conn.model()`. Otherwise, [any middleware the plugin registers won't get applied](/docs/middleware.html#defining).
+
+    ```javascript
+    // loadedAt.js
+    module.exports = function loadedAtPlugin(schema, options) {
+      schema.virtual('loadedAt').
+        get(function() { return this._loadedAt; }).
+        set(function(v) { this._loadedAt = v; });
+
+      schema.post(['find', 'findOne'], function(docs) {
+        if (!Array.isArray(docs)) {
+          docs = [docs];
+        }
+        const now = new Date();
+        for (const doc of docs) {
+          doc.loadedAt = now;
+        }
+      });
+    };
+
+    // game-schema.js
+    const loadedAtPlugin = require('./loadedAt');
+    const gameSchema = new Schema({ ... });
+    const Game = mongoose.model('Game', gameSchema);
+
+    // `find()` and `findOne()` hooks from `loadedAtPlugin()` won't get applied
+    // because `mongoose.model()` was already called!
+    gameSchema.plugin(loadedAtPlugin);
+    ```
+
     <h3 id="official"><a href="#official">Officially Supported Plugins</a></h3>
 
     The Mongoose team maintains several plugins that add cool new features to

From 8c8751f70746f39cc843d461e4d9dcc15528a220 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 26 Aug 2020 21:03:12 -0400
Subject: [PATCH 1156/2348] test: repro #9361

---
 test/schema.select.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/schema.select.test.js b/test/schema.select.test.js
index 43cc1ca5200..eb61e541e77 100644
--- a/test/schema.select.test.js
+++ b/test/schema.select.test.js
@@ -324,6 +324,27 @@ describe('schema select option', function() {
     });
   });
 
+  it('should not project in discriminator key if projected in implicitly with .$ (gh-9361)', function() {
+    const eventSchema = new Schema({ message: String },
+      { discriminatorKey: 'kind', _id: false });
+
+    const batchSchema = new Schema({ events: [eventSchema] });
+    batchSchema.path('events').discriminator('Clicked', new Schema({
+      element: String
+    }, { _id: false }));
+    batchSchema.path('events').discriminator('Purchased', new Schema({
+      product: String
+    }, { _id: false }));
+
+    const MyModel = db.model('Test', batchSchema);
+
+    const query = MyModel.find({ 'events.message': 'foo' }).select({ 'events.$': 1 });
+    query._applyPaths();
+
+    assert.equal(Object.keys(query._fields).length, 1);
+    assert.ok(query._fields['events.$']);
+  });
+
   describe('forcing inclusion of a deselected schema path', function() {
     it('works', function(done) {
       const excluded = new Schema({

From d48cfa111323f5b73233f4cd00b7eaa70a7a0006 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 26 Aug 2020 21:19:26 -0400
Subject: [PATCH 1157/2348] fix(queryhelpers): avoid path collision error when
 projecting in discriminator key with `.$`

Re: #9361
---
 lib/queryhelpers.js              |  2 +-
 test/model.discriminator.test.js | 18 +++++++++++-------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 53a6f613613..d0e93b65b42 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -261,7 +261,7 @@ exports.applyPaths = function applyPaths(fields, schema) {
       let cur = '';
       for (let i = 0; i < pieces.length; ++i) {
         cur += (cur.length === 0 ? '' : '.') + pieces[i];
-        const projection = get(fields, cur, false);
+        const projection = get(fields, cur, false) || get(fields, cur + '.$', false);
         if (projection && typeof projection !== 'object') {
           return;
         }
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index cc1838aa2cc..0b50a0b6b07 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -762,31 +762,35 @@ describe('model', function() {
 
       it('with $meta projection (gh-5859)', function() {
         const eventSchema = new Schema({ eventField: String }, { id: false });
+        eventSchema.index({ eventField: 'text' });
         const Event = db.model('Test', eventSchema);
 
         const trackSchema = new Schema({ trackField: String });
         const Track = Event.discriminator('Track', trackSchema);
 
         const trackedItem = new Track({
-          trackField: 'trackField',
-          eventField: 'eventField'
+          trackField: 'track',
+          eventField: 'event'
         });
 
         return trackedItem.save().
+          then(() => Event.init()).
           then(function() {
-            return Event.find({}).select({ score: { $meta: 'textScore' } });
+            return Event.find({ $text: { $search: 'event' } }).
+              select({ score: { $meta: 'textScore' } });
           }).
           then(function(docs) {
             assert.equal(docs.length, 1);
-            assert.equal(docs[0].trackField, 'trackField');
+            assert.equal(docs[0].trackField, 'track');
           }).
           then(function() {
-            return Track.find({}).select({ score: { $meta: 'textScore' } });
+            return Track.find({ $text: { $search: 'event' } }).
+              select({ score: { $meta: 'textScore' } });
           }).
           then(function(docs) {
             assert.equal(docs.length, 1);
-            assert.equal(docs[0].trackField, 'trackField');
-            assert.equal(docs[0].eventField, 'eventField');
+            assert.equal(docs[0].trackField, 'track');
+            assert.equal(docs[0].eventField, 'event');
           });
       });
 

From 3ec17eb083ad9ffc1a21b6fe154bd3ae09726853 Mon Sep 17 00:00:00 2001
From: Evander Palacios <biomorgoth.palacios@gmail.com>
Date: Thu, 27 Aug 2020 11:17:28 -0400
Subject: [PATCH 1158/2348] Implement cursor population in batches, only if a
 custom batchSize is set on the query

---
 lib/cursor/QueryCursor.js |  91 ++++++++++++++++++++------
 test/query.cursor.test.js | 131 ++++++++++++++++++++++++++++++--------
 2 files changed, 176 insertions(+), 46 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index a77f5bb472a..0356d95fb7d 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -295,33 +295,82 @@ function _next(ctx, cb) {
   }
 
   if (ctx.cursor) {
-    return ctx.cursor.next(function(error, doc) {
-      if (error) {
-        return callback(error);
-      }
-      if (!doc) {
+    function nextDoc(doc, pop) {
+      return ctx.query._mongooseOptions.lean ?
+        callback(null, doc) :
+        _create(ctx, doc, pop, callback);
+    }
+    if (ctx.query._mongooseOptions.populate && !ctx._pop) {
+      ctx._pop = helpers.preparePopulationOptionsMQ(ctx.query,
+        ctx.query._mongooseOptions);
+      ctx._pop.__noPromise = true;
+    }
+    if (ctx.query._mongooseOptions.populate && ctx.options.batchSize > 1) {
+      if (ctx._batchDocs && ctx._batchDocs.length) {
+        // Return a cached populated doc
+        return nextDoc(ctx._batchDocs.shift(), ctx._pop);
+      } else if (ctx._batchExhausted) {
+        // Internal cursor reported no more docs. Act the same here
         return callback(null, null);
-      }
+      } else {
+        const _batchDocs = []
+        // Request as many docs as batchSize, to populate them also in batch
+        function populateBatch() {
+          if (!_batchDocs.length) {
+            return callback(null, null);
+          }
+          ctx.query.model.populate(_batchDocs, ctx._pop, function(err, docs) {
+            if (err) {
+              return callback(err);
+            }
+
+            ctx._batchDocs = docs
+
+            nextDoc(ctx._batchDocs.shift(), ctx._pop);
+          });
+        }
+
+        function onNext(error, doc) {
+          if (error) {
+            return callback(error);
+          }
+          if (!doc) {
+            ctx._batchExhausted = true
+            return populateBatch();
+          }
 
-      const opts = ctx.query._mongooseOptions;
-      if (!opts.populate) {
-        return opts.lean ?
-          callback(null, doc) :
-          _create(ctx, doc, null, callback);
+          _batchDocs.push(doc);
+
+          if (_batchDocs.length < ctx.options.batchSize) {
+            ctx.cursor.next(onNext);
+          } else {
+            populateBatch();
+          }
+        }
+
+        return ctx.cursor.next(onNext);
       }
+    } else {
+      return ctx.cursor.next(function(error, doc) {
+        if (error) {
+          return callback(error);
+        }
+        if (!doc) {
+          return callback(null, null);
+        }
 
-      const pop = helpers.preparePopulationOptionsMQ(ctx.query,
-        ctx.query._mongooseOptions);
-      pop.__noPromise = true;
-      ctx.query.model.populate(doc, pop, function(err, doc) {
-        if (err) {
-          return callback(err);
+        if (!ctx.query._mongooseOptions.populate) {
+          return nextDoc(doc, null);
         }
-        return opts.lean ?
-          callback(null, doc) :
-          _create(ctx, doc, pop, callback);
+
+        ctx.query.model.populate(doc, ctx._pop, function(err, doc) {
+          if (err) {
+            return callback(err);
+          }
+          return nextDoc(doc, ctx._pop);
+        });
       });
-    });
+    }
   } else {
     ctx.once('cursor', function() {
       _next(ctx, cb);
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index b184a2bd3de..639ceac399f 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -108,7 +108,7 @@ describe('QueryCursor', function() {
       });
     });
 
-    it('with populate', function(done) {
+    describe('with populate', function() {
       const bandSchema = new Schema({
         name: String,
         members: [{ type: mongoose.Schema.ObjectId, ref: 'Person' }]
@@ -117,37 +117,118 @@ describe('QueryCursor', function() {
         name: String
       });
 
-      const Person = db.model('Person', personSchema);
-      const Band = db.model('Band', bandSchema);
+      let Band;
 
-      const people = [
-        { name: 'Axl Rose' },
-        { name: 'Slash' },
-        { name: 'Nikki Sixx' },
-        { name: 'Vince Neil' }
-      ];
-      Person.create(people, function(error, docs) {
-        assert.ifError(error);
-        const bands = [
-          { name: 'Guns N\' Roses', members: [docs[0], docs[1]] },
-          { name: 'Motley Crue', members: [docs[2], docs[3]] }
+      beforeEach(function(done) {
+        const Person = db.model('Person', personSchema);
+        Band = db.model('Band', bandSchema);
+
+        const people = [
+          { name: 'Axl Rose' },
+          { name: 'Slash' },
+          { name: 'Nikki Sixx' },
+          { name: 'Vince Neil' },
+          { name: 'Trent Reznor' },
+          { name: 'Thom Yorke' },
+          { name: 'Billy Corgan' }
         ];
-        Band.create(bands, function(error) {
+        Person.create(people, function(error, docs) {
+          assert.ifError(error);
+          const bands = [
+            { name: 'Guns N\' Roses', members: [docs[0], docs[1]] },
+            { name: 'Motley Crue', members: [docs[2], docs[3]] },
+            { name: 'Nine Inch Nails', members: [docs[4]] },
+            { name: 'Radiohead', members: [docs[5]] },
+            { name: 'The Smashing Pumpkins', members: [docs[6]] }
+          ];
+          Band.create(bands, function(error) {
+            assert.ifError(error);
+            done();
+          });
+        });
+      });
+
+      it('with populate without specify batchSize', function(done) {
+        const cursor =
+          Band.find().sort({ name: 1 }).populate('members').cursor();
+        cursor.next(function(error, doc) {
+          assert.ifError(error);
+          assert.equal(cursor.cursor.cursorState.currentLimit, 1);
+          assert.equal(doc.name, 'Guns N\' Roses');
+          assert.equal(doc.members.length, 2);
+          assert.equal(doc.members[0].name, 'Axl Rose');
+          assert.equal(doc.members[1].name, 'Slash');
+          cursor.next(function(error, doc) {
+            assert.ifError(error);
+            assert.equal(cursor.cursor.cursorState.currentLimit, 2);
+            assert.equal(doc.name, 'Motley Crue');
+            assert.equal(doc.members.length, 2);
+            assert.equal(doc.members[0].name, 'Nikki Sixx');
+            assert.equal(doc.members[1].name, 'Vince Neil');
+            cursor.next(function(error, doc) {
+              assert.ifError(error);
+              assert.equal(cursor.cursor.cursorState.currentLimit, 3);
+              assert.equal(doc.name, 'Nine Inch Nails');
+              assert.equal(doc.members.length, 1);
+              assert.equal(doc.members[0].name, 'Trent Reznor');
+              cursor.next(function(error, doc) {
+                assert.ifError(error);
+                assert.equal(cursor.cursor.cursorState.currentLimit, 4);
+                assert.equal(doc.name, 'Radiohead');
+                assert.equal(doc.members.length, 1);
+                assert.equal(doc.members[0].name, 'Thom Yorke');
+                cursor.next(function(error, doc) {
+                  assert.ifError(error);
+                  assert.equal(cursor.cursor.cursorState.currentLimit, 5);
+                  assert.equal(doc.name, 'The Smashing Pumpkins');
+                  assert.equal(doc.members.length, 1);
+                  assert.equal(doc.members[0].name, 'Billy Corgan');
+                  done();
+                });
+              });
+            });
+          });
+        });
+      });
+
+      it('with populate using custom batchSize', function(done) {
+        const cursor =
+          Band.find().sort({ name: 1 }).populate('members').batchSize(3).cursor();
+        cursor.next(function(error, doc) {
           assert.ifError(error);
-          const cursor =
-            Band.find().sort({ name: 1 }).populate('members').cursor();
+          assert.equal(cursor.cursor.cursorState.currentLimit, 3);
+          assert.equal(doc.name, 'Guns N\' Roses');
+          assert.equal(doc.members.length, 2);
+          assert.equal(doc.members[0].name, 'Axl Rose');
+          assert.equal(doc.members[1].name, 'Slash');
           cursor.next(function(error, doc) {
             assert.ifError(error);
-            assert.equal(doc.name, 'Guns N\' Roses');
+            assert.equal(cursor.cursor.cursorState.currentLimit, 3);
+            assert.equal(doc.name, 'Motley Crue');
             assert.equal(doc.members.length, 2);
-            assert.equal(doc.members[0].name, 'Axl Rose');
-            assert.equal(doc.members[1].name, 'Slash');
+            assert.equal(doc.members[0].name, 'Nikki Sixx');
+            assert.equal(doc.members[1].name, 'Vince Neil');
             cursor.next(function(error, doc) {
-              assert.equal(doc.name, 'Motley Crue');
-              assert.equal(doc.members.length, 2);
-              assert.equal(doc.members[0].name, 'Nikki Sixx');
-              assert.equal(doc.members[1].name, 'Vince Neil');
-              done();
+              assert.ifError(error);
+              assert.equal(cursor.cursor.cursorState.currentLimit, 3);
+              assert.equal(doc.name, 'Nine Inch Nails');
+              assert.equal(doc.members.length, 1);
+              assert.equal(doc.members[0].name, 'Trent Reznor');
+              cursor.next(function(error, doc) {
+                assert.ifError(error);
+                assert.equal(cursor.cursor.cursorState.currentLimit, 5);
+                assert.equal(doc.name, 'Radiohead');
+                assert.equal(doc.members.length, 1);
+                assert.equal(doc.members[0].name, 'Thom Yorke');
+                cursor.next(function(error, doc) {
+                  assert.ifError(error);
+                  assert.equal(cursor.cursor.cursorState.currentLimit, 5);
+                  assert.equal(doc.name, 'The Smashing Pumpkins');
+                  assert.equal(doc.members.length, 1);
+                  assert.equal(doc.members[0].name, 'Billy Corgan');
+                  done();
+                });
+              });
             });
           });
         });

From c78c42db84260489d702d845fb639503dbfaa418 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Aug 2020 12:02:10 -0400
Subject: [PATCH 1159/2348] test(document): repro #9319

---
 test/document.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 6d5bb42fc8c..15c5b9097ca 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9286,4 +9286,29 @@ describe('document', function() {
     const doc = new Test({ publisher: 'Mastering JS' });
     assert.deepEqual(doc.toObject().authors, ['Mastering JS']);
   });
+
+  it('handles pulling array subdocs when _id is an alias (gh-9319)', function() {
+    const childSchema = Schema({
+      field: {
+        type: String,
+        alias: '_id'
+      }
+    }, { _id: false });
+
+    const parentSchema = Schema({ children: [childSchema] });
+    const Parent = db.model('Parent', parentSchema);
+
+    return co(function*() {
+      yield Parent.create({ children: [{ field: '1' }] });
+      const p = yield Parent.findOne();
+
+      p.children.pull('1');
+      yield p.save();
+
+      assert.equal(p.children.length, 0);
+
+      const fromDb = yield Parent.findOne();
+      assert.equal(fromDb.children.length, 0);
+    });
+  });
 });

From 568acaf29202a9117b0e2de04c0e8d2045feb481 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Aug 2020 12:02:20 -0400
Subject: [PATCH 1160/2348] fix(document): handle `pull()` on a document array
 when `_id` is an alias

Fix #9319
---
 lib/document.js         | 4 ++--
 lib/types/core_array.js | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 7598bdea93f..4d496da979c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3667,8 +3667,8 @@ Document.prototype.equals = function(doc) {
     return false;
   }
 
-  const tid = this.get('_id');
-  const docid = doc.get ? doc.get('_id') : doc;
+  const tid = this.$__getValue('_id');
+  const docid = doc.$__ != null ? doc.$__getValue('_id') : doc;
   if (!tid && !docid) {
     return deepEqual(this, doc);
   }
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 423933f42b7..2e1c5c75ecd 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -605,7 +605,7 @@ class CoreMongooseArray extends Array {
 
     if (values[0] instanceof EmbeddedDocument) {
       this._registerAtomic('$pullDocs', values.map(function(v) {
-        return v._id || v;
+        return v.$__getValue('_id') || v;
       }));
     } else {
       this._registerAtomic('$pullAll', values);

From cf68cdc1f5464cd76e982a56c5a347ea05193f36 Mon Sep 17 00:00:00 2001
From: Evander Palacios <biomorgoth.palacios@gmail.com>
Date: Thu, 27 Aug 2020 12:23:26 -0400
Subject: [PATCH 1161/2348] ESLint changes

---
 lib/cursor/QueryCursor.js | 99 ++++++++++++++++++++++-----------------
 1 file changed, 56 insertions(+), 43 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 0356d95fb7d..bbcb9f3d99d 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -295,11 +295,6 @@ function _next(ctx, cb) {
   }
 
   if (ctx.cursor) {
-    function nextDoc(doc, pop) {
-      return ctx.query._mongooseOptions.lean ?
-        callback(null, doc) :
-        _create(ctx, doc, pop, callback);
-    }
     if (ctx.query._mongooseOptions.populate && !ctx._pop) {
       ctx._pop = helpers.preparePopulationOptionsMQ(ctx.query,
         ctx.query._mongooseOptions);
@@ -308,47 +303,13 @@ function _next(ctx, cb) {
     if (ctx.query._mongooseOptions.populate && ctx.options.batchSize > 1) {
       if (ctx._batchDocs && ctx._batchDocs.length) {
         // Return a cached populated doc
-        return nextDoc(ctx._batchDocs.shift(), ctx._pop);
+        return _nextDoc(ctx, ctx._batchDocs.shift(), ctx._pop, callback);
       } else if (ctx._batchExhausted) {
         // Internal cursor reported no more docs. Act the same here
         return callback(null, null);
       } else {
-        const _batchDocs = []
         // Request as many docs as batchSize, to populate them also in batch
-        function populateBatch() {
-          if (!_batchDocs.length) {
-            return callback(null, null);
-          }
-          ctx.query.model.populate(_batchDocs, ctx._pop, function(err, docs) {
-            if (err) {
-              return callback(err);
-            }
-
-            ctx._batchDocs = docs
-
-            nextDoc(ctx._batchDocs.shift(), ctx._pop);
-          });
-        }
-
-        function onNext(error, doc) {
-          if (error) {
-            return callback(error);
-          }
-          if (!doc) {
-            ctx._batchExhausted = true
-            return populateBatch();
-          }
-
-          _batchDocs.push(doc);
-
-          if (_batchDocs.length < ctx.options.batchSize) {
-            ctx.cursor.next(onNext);
-          } else {
-            populateBatch();
-          }
-        }
-
-        return ctx.cursor.next(onNext);
+        return ctx.cursor.next(_onNext.bind({ ctx, callback, batchDocs: [] }));
       }
     } else {
       return ctx.cursor.next(function(error, doc) {
@@ -360,14 +321,14 @@ function _next(ctx, cb) {
         }
 
         if (!ctx.query._mongooseOptions.populate) {
-          return nextDoc(doc, null);
+          return _nextDoc(ctx, doc, null, callback);
         }
 
         ctx.query.model.populate(doc, ctx._pop, function(err, doc) {
           if (err) {
             return callback(err);
           }
-          return nextDoc(doc, ctx._pop);
+          return _nextDoc(ctx, doc, ctx._pop, callback);
         });
       });
     }
@@ -378,6 +339,58 @@ function _next(ctx, cb) {
   }
 }
 
+/*!
+ * ignore
+ */
+
+function _onNext(error, doc) {
+  if (error) {
+    return this.callback(error);
+  }
+  if (!doc) {
+    this.ctx._batchExhausted = true;
+    return _populateBatch.call(this);
+  }
+
+  this.batchDocs.push(doc);
+
+  if (this.batchDocs.length < this.ctx.options.batchSize) {
+    this.ctx.cursor.next(_onNext.bind(this));
+  } else {
+    _populateBatch.call(this);
+  }
+}
+
+/*!
+ * ignore
+ */
+
+function _populateBatch() {
+  if (!this.batchDocs.length) {
+    return this.callback(null, null);
+  }
+  const _this = this;
+  this.ctx.query.model.populate(this.batchDocs, this.ctx._pop, function(err, docs) {
+    if (err) {
+      return _this.callback(err);
+    }
+
+    _this.ctx._batchDocs = docs;
+
+    _nextDoc(_this.ctx, _this.ctx._batchDocs.shift(), _this.ctx._pop, _this.callback);
+  });
+}
+
+/*!
+ * ignore
+ */
+
+function _nextDoc(ctx, doc, pop, callback) {
+  return ctx.query._mongooseOptions.lean ?
+    callback(null, doc) :
+    _create(ctx, doc, pop, callback);
+}
+
 /*!
  * ignore
  */

From a31ec95d56e9547b42eecf7ca29ac9abddab7ff7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Aug 2020 13:36:23 -0400
Subject: [PATCH 1162/2348] docs(built-with-mongoose): add terra vera

---
 docs/built-with-mongoose.pug | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
index 69d5b13bf25..2c30c30dce4 100644
--- a/docs/built-with-mongoose.pug
+++ b/docs/built-with-mongoose.pug
@@ -12,7 +12,23 @@ block content
     over 870,000 projects that depend on Mongoose. Here are a few of
     our favorite apps that are built with Mongoose.
 
-    <div style="position: relative">
+    <div style="position: relative; margin-top: 1em;">
+      <div style="position: absolute; width: 100px; height: 100px">
+        <a href="https://terravera.com">
+          <img src="https://terravera.com/images/avatar.png">
+        </a>
+      </div>
+      <div style="padding-left: 110px; min-height: 100px">
+        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
+          <a href="https://terravera.com">
+            Terra Vera
+          </a>
+        </h4>
+        Terra Vera produces on-demand antimicrobial chemistry for agriculture and surfaces. Terra Vera's on-site generators convert water, electricity, and a proprietary blend of salts and amino acids into an organic solution that eliminates many common pathogens (like mold, powdery mildew, and viruses), but is safe for plants, people, and pets.
+      </div>
+    </div>
+
+    <div style="position: relative; margin-top: 1em;">
       <div style="position: absolute; width: 100px; height: 100px">
         <a href="https://sixplus.com">
           <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1452784634/wipgioqzev0omt4ezsay.jpg">

From 54cae5509b675ca939ce38bd2772c74c30f274a3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 Aug 2020 13:37:20 -0400
Subject: [PATCH 1163/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 371020ede87..cb0b8086588 100644
--- a/index.pug
+++ b/index.pug
@@ -358,6 +358,9 @@ html(lang='en')
               <a href="https://www.baocasino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/baocasino/b5a71c4/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://onlinecasinoguide.co.nz/">
+                <img class="sponsor" src="https://images.opencollective.com/onlinecasinoguide-co-nz/b16a388/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 9076a4051b1fa229c862334b97202cf8d07bd46d Mon Sep 17 00:00:00 2001
From: Timothy Haley <tim.d.haley@gmail.com>
Date: Thu, 27 Aug 2020 14:05:11 -0400
Subject: [PATCH 1164/2348] Fix typo in error message thrown by unimplemented
 createIndex

---
 lib/collection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/collection.js b/lib/collection.js
index 2f5d188b012..97f5bb3238e 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -143,7 +143,7 @@ Collection.prototype.ensureIndex = function() {
  */
 
 Collection.prototype.createIndex = function() {
-  throw new Error('Collection#ensureIndex unimplemented by driver');
+  throw new Error('Collection#createIndex unimplemented by driver');
 };
 
 /**

From 9f2ebdb4da889e707bbdd2b619dc9fd10d220330 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 09:24:26 -0400
Subject: [PATCH 1165/2348] test: fix tests on MongoDB 4.4

Fix #9361
---
 test/schema.select.test.js | 52 +++++++++++++++-----------------------
 1 file changed, 20 insertions(+), 32 deletions(-)

diff --git a/test/schema.select.test.js b/test/schema.select.test.js
index eb61e541e77..e12c45fecb0 100644
--- a/test/schema.select.test.js
+++ b/test/schema.select.test.js
@@ -502,13 +502,9 @@ describe('schema select option', function() {
     });
 
     const M = db.model('Test', schema);
-    M.find().select('_id -name').exec(function(err) {
-      assert.ok(err instanceof Error, 'conflicting path selection error should be instance of Error');
-
-      M.find().select('_id').exec(function(err) {
-        assert.ifError(err, err && err.stack);
-        done();
-      });
+    M.find().select('_id').exec(function(err) {
+      assert.ifError(err, err && err.stack);
+      done();
     });
   });
 
@@ -518,13 +514,9 @@ describe('schema select option', function() {
     });
 
     const M = db.model('Test', schema);
-    M.find().select('_id -docs.name').exec(function(err) {
-      assert.ok(err instanceof Error, 'conflicting path selection error should be instance of Error');
-
-      M.find().select('_id').exec(function(err) {
-        assert.ifError(err, err && err.stack);
-        done();
-      });
+    M.find().select('_id').exec(function(err) {
+      assert.ifError(err, err && err.stack);
+      done();
     });
   });
 
@@ -550,27 +542,23 @@ describe('schema select option', function() {
     const T = db.model('Test3', schema2);
 
     function useId(M, id, cb) {
-      M.findOne().select('_id -name').exec(function(err, d) {
-        assert.ok(err);
-        assert.ok(!d);
-        M.findOne().select('-_id name').exec(function(err, d) {
-          // mongo special case for exclude _id + include path
+      M.findOne().select('-_id name').exec(function(err, d) {
+        // mongo special case for exclude _id + include path
+        assert.ifError(err);
+        assert.equal(d.id, undefined);
+        assert.equal(d.name, 'ssd');
+        assert.equal(d.age, undefined);
+        M.findOne().select('-_id -name').exec(function(err, d) {
           assert.ifError(err);
           assert.equal(d.id, undefined);
-          assert.equal(d.name, 'ssd');
-          assert.equal(d.age, undefined);
-          M.findOne().select('-_id -name').exec(function(err, d) {
+          assert.equal(d.name, undefined);
+          assert.equal(d.age, 0);
+          M.findOne().select('_id name').exec(function(err, d) {
             assert.ifError(err);
-            assert.equal(d.id, undefined);
-            assert.equal(d.name, undefined);
-            assert.equal(d.age, 0);
-            M.findOne().select('_id name').exec(function(err, d) {
-              assert.ifError(err);
-              assert.equal(d.id, id);
-              assert.equal(d.name, 'ssd');
-              assert.equal(d.age, undefined);
-              cb();
-            });
+            assert.equal(d.id, id);
+            assert.equal(d.name, 'ssd');
+            assert.equal(d.age, undefined);
+            cb();
           });
         });
       });

From 648e6e6d9f21eadd19ef7e2a600cc671ce39b032 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 10:03:00 -0400
Subject: [PATCH 1166/2348] fix(model): avoid uncaught error if `insertMany()`
 fails due to server selection error

Fix #9355
---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 4ce3e39e648..84b4220bd3d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3323,7 +3323,7 @@ Model.$__insertMany = function(arr, options, callback) {
         }
 
         // `insertedDocs` is a Mongoose-specific property
-        const erroredIndexes = new Set(error.writeErrors.map(err => err.index));
+        const erroredIndexes = new Set(get(error, 'writeErrors', []).map(err => err.index));
         error.insertedDocs = docAttributes.filter((doc, i) => {
           return !erroredIndexes.has(i);
         });

From ef87058203e0cf257e8eeaac3fac950b83ce9057 Mon Sep 17 00:00:00 2001
From: Evander Palacios <biomorgoth.palacios@gmail.com>
Date: Fri, 28 Aug 2020 10:53:24 -0400
Subject: [PATCH 1167/2348] No need to use a separate batchDocs array, as
 populate modifies docs in-place

---
 lib/cursor/QueryCursor.js | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index bbcb9f3d99d..194b2825e53 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -309,7 +309,8 @@ function _next(ctx, cb) {
         return callback(null, null);
       } else {
         // Request as many docs as batchSize, to populate them also in batch
-        return ctx.cursor.next(_onNext.bind({ ctx, callback, batchDocs: [] }));
+        ctx._batchDocs = [];
+        return ctx.cursor.next(_onNext.bind({ ctx, callback }));
       }
     } else {
       return ctx.cursor.next(function(error, doc) {
@@ -352,9 +353,9 @@ function _onNext(error, doc) {
     return _populateBatch.call(this);
   }
 
-  this.batchDocs.push(doc);
+  this.ctx._batchDocs.push(doc);
 
-  if (this.batchDocs.length < this.ctx.options.batchSize) {
+  if (this.ctx._batchDocs.length < this.ctx.options.batchSize) {
     this.ctx.cursor.next(_onNext.bind(this));
   } else {
     _populateBatch.call(this);
@@ -366,17 +367,15 @@ function _onNext(error, doc) {
  */
 
 function _populateBatch() {
-  if (!this.batchDocs.length) {
+  if (!this.ctx._batchDocs.length) {
     return this.callback(null, null);
   }
   const _this = this;
-  this.ctx.query.model.populate(this.batchDocs, this.ctx._pop, function(err, docs) {
+  this.ctx.query.model.populate(this.ctx._batchDocs, this.ctx._pop, function(err) {
     if (err) {
       return _this.callback(err);
     }
 
-    _this.ctx._batchDocs = docs;
-
     _nextDoc(_this.ctx, _this.ctx._batchDocs.shift(), _this.ctx._pop, _this.callback);
   });
 }

From a76c54f04d29ff2de28127c1672636baa61703b5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 10:54:09 -0400
Subject: [PATCH 1168/2348] fix(aggregate): automatically convert accumulator
 function options to strings

Fix #9364
---
 lib/aggregate.js                              |  3 +-
 .../aggregate/stringifyAccumulatorOptions.js  | 38 ++++++++++++++++
 test/helpers/aggregate.test.js                | 45 +++++++++++++++++++
 3 files changed, 85 insertions(+), 1 deletion(-)
 create mode 100644 lib/helpers/aggregate/stringifyAccumulatorOptions.js
 create mode 100644 test/helpers/aggregate.test.js

diff --git a/lib/aggregate.js b/lib/aggregate.js
index d275c2ed4da..bc53742bd8f 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -8,6 +8,7 @@ const AggregationCursor = require('./cursor/AggregationCursor');
 const Query = require('./query');
 const applyGlobalMaxTimeMS = require('./helpers/query/applyGlobalMaxTimeMS');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
+const stringifyAccumulatorOptions = require('./helpers/aggregate/stringifyAccumulatorOptions');
 const util = require('util');
 const utils = require('./utils');
 const read = Query.prototype.read;
@@ -982,8 +983,8 @@ Aggregate.prototype.exec = function(callback) {
   }
 
   return promiseOrCallback(callback, cb => {
-
     prepareDiscriminatorPipeline(this);
+    stringifyAccumulatorOptions(this._pipeline);
 
     model.hooks.execPre('aggregate', this, error => {
       if (error) {
diff --git a/lib/helpers/aggregate/stringifyAccumulatorOptions.js b/lib/helpers/aggregate/stringifyAccumulatorOptions.js
new file mode 100644
index 00000000000..7362514d8f5
--- /dev/null
+++ b/lib/helpers/aggregate/stringifyAccumulatorOptions.js
@@ -0,0 +1,38 @@
+'use strict';
+
+module.exports = function stringifyAccumulatorOptions(pipeline) {
+  if (!Array.isArray(pipeline)) {
+    return;
+  }
+
+  for (const stage of pipeline) {
+    if (stage == null) {
+      continue;
+    }
+
+    const canHaveAccumulator = stage.$group || stage.$bucket || stage.$bucketAuto;
+    if (canHaveAccumulator != null) {
+      for (const key of Object.keys(canHaveAccumulator)) {
+        handleAccumulator(canHaveAccumulator[key]);
+      }
+    }
+
+    if (stage.$facet != null) {
+      for (const key of Object.keys(stage.$facet)) {
+        stringifyAccumulatorOptions(stage.$facet[key]);
+      }
+    }
+  }
+};
+
+function handleAccumulator(operator) {
+  if (operator == null || operator.$accumulator == null) {
+    return;
+  }
+
+  for (const key of ['init', 'accumulate', 'merge', 'finalize']) {
+    if (typeof operator.$accumulator[key] === 'function') {
+      operator.$accumulator[key] = String(operator.$accumulator[key]);
+    }
+  }
+}
\ No newline at end of file
diff --git a/test/helpers/aggregate.test.js b/test/helpers/aggregate.test.js
new file mode 100644
index 00000000000..c3683cea959
--- /dev/null
+++ b/test/helpers/aggregate.test.js
@@ -0,0 +1,45 @@
+'use strict';
+
+const assert = require('assert');
+const stringifyAccumulatorOptions = require('../../lib/helpers/aggregate/stringifyAccumulatorOptions');
+
+describe('stringifyAccumulatorOptions', function() {
+  it('converts accumulator args to strings (gh-9364)', function() {
+    const pipeline = [{
+      $group: {
+        _id: '$author',
+        avgCopies: {
+          $accumulator: {
+            init: function() {
+              return { count: 0, sum: 0 };
+            },
+            accumulate: function(state, numCopies) {
+              return {
+                count: state.count + 1,
+                sum: state.sum + numCopies
+              };
+            },
+            accumulateArgs: ['$copies'],
+            merge: function(state1, state2) {
+              return {
+                count: state1.count + state2.count,
+                sum: state1.sum + state2.sum
+              };
+            },
+            finalize: function(state) {
+              return (state.sum / state.count);
+            },
+            lang: 'js'
+          }
+        }
+      }
+    }];
+
+    stringifyAccumulatorOptions(pipeline);
+
+    assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.init, 'string');
+    assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.accumulate, 'string');
+    assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.merge, 'string');
+    assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.finalize, 'string');
+  });
+});
\ No newline at end of file

From cc32a0edb2b18a411c9e0cf71589a3ec3c67ca17 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 11:10:11 -0400
Subject: [PATCH 1169/2348] chore: release 5.10.2

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 2ec5349ebed..53c87387fc7 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.10.2 / 2020-08-28
+===================
+ * fix(model): avoid uncaught error if `insertMany()` fails due to server selection error #9355
+ * fix(aggregate): automatically convert accumulator function options to strings #9364
+ * fix(document): handle `pull()` on a document array when `_id` is an alias #9319
+ * fix(queryhelpers): avoid path collision error when projecting in discriminator key with `.$` #9361
+ * fix: fix typo in error message thrown by unimplemented createIndex #9367 [timhaley94](https://github.com/timhaley94)
+ * docs(plugins): note that plugins should be applied before you call `mongoose.model()` #7723
+
 5.10.1 / 2020-08-26
 ===================
  * fix(mongoose): fix `.then()` is not a function error when calling `mongoose.connect()` multiple times #9358 #9335 #9331
diff --git a/package.json b/package.json
index a0ced576dd1..a44b35c9fb7 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.1",
+  "version": "5.10.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 6e3699130eb34890bf493a8e4067c6560a3d5d47 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 12:55:47 -0400
Subject: [PATCH 1170/2348] test(update): repro #9298

---
 test/model.update.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 3e1a2aa7f4d..7102679301c 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3128,6 +3128,25 @@ describe('model: updateOne: ', function() {
     });
   });
 
+  it('updating a map path underneath a single nested subdoc (gh-9298)', function() {
+    const schema = Schema({
+      cities: {
+        type: Map,
+        of: Schema({ population: Number })
+      }
+    });
+    const Test = db.model('Test', Schema({ country: schema }));
+
+    return co(function*() {
+      yield Test.create({});
+
+      yield Test.updateOne({}, { 'country.cities.newyork.population': '10000' });
+
+      const updated = yield Test.findOne({}).lean();
+      assert.strictEqual(updated.country.cities.newyork.population, 10000);
+    });
+  });
+
   it('overwrite an array with empty (gh-7135)', function() {
     const ElementSchema = Schema({
       a: { type: String, required: true }

From 63a34bec66f263c96a72d0ffb2f28a6c563a2a12 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 12:55:58 -0400
Subject: [PATCH 1171/2348] fix(update): handle casting map paths when map is
 underneath a single nested subdoc

Fix #9298
---
 lib/schema.js | 38 +++++++++++++++++++++++---------------
 1 file changed, 23 insertions(+), 15 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index b7099cb8bac..d94565e21bb 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -2053,29 +2053,37 @@ Schema.prototype._getSchema = function(path) {
           // doesn't work for that.
           // If there is no foundschema.schema we are dealing with
           // a path like array.$
-          if (p !== parts.length && foundschema.schema) {
-            let ret;
-            if (parts[p] === '$' || isArrayFilter(parts[p])) {
-              if (p + 1 === parts.length) {
-                // comments.$
-                return foundschema;
+          if (p !== parts.length) {
+            if (foundschema.schema) {
+              let ret;
+              if (parts[p] === '$' || isArrayFilter(parts[p])) {
+                if (p + 1 === parts.length) {
+                  // comments.$
+                  return foundschema;
+                }
+                // comments.$.comments.$.title
+                ret = search(parts.slice(p + 1), foundschema.schema);
+                if (ret) {
+                  ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
+                    !foundschema.schema.$isSingleNested;
+                }
+                return ret;
               }
-              // comments.$.comments.$.title
-              ret = search(parts.slice(p + 1), foundschema.schema);
+              // this is the last path of the selector
+              ret = search(parts.slice(p), foundschema.schema);
               if (ret) {
                 ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
                   !foundschema.schema.$isSingleNested;
               }
               return ret;
             }
-            // this is the last path of the selector
-            ret = search(parts.slice(p), foundschema.schema);
-            if (ret) {
-              ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
-                !foundschema.schema.$isSingleNested;
-            }
-            return ret;
           }
+        } else if (foundschema.$isSchemaMap) {
+          if (p + 1 >= parts.length) {
+            return foundschema.$__schemaType;
+          }
+          const ret = search(parts.slice(p + 1), foundschema.$__schemaType.schema);
+          return ret;
         }
 
         foundschema.$fullPath = resultPath.join('.');

From b6ca98db3de407e3ef56be36256261cc1b1346b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 13:54:28 -0400
Subject: [PATCH 1172/2348] test(timestamps): repro #9357

---
 test/schema.timestamps.test.js | 36 ++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index de7d321eff8..db6e2a1b81c 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -406,4 +406,40 @@ describe('schema options.timestamps', function() {
       assert.equal(doc.updatedAt, 42);
     });
   });
+
+  it('shouldnt bump updatedAt in single nested subdocs that are not modified (gh-9357)', function() {
+    const nestedSchema = Schema({
+      nestedA: { type: String },
+      nestedB: { type: String }
+    }, { timestamps: true });
+    const parentSchema = Schema({
+      content: {
+        a: nestedSchema,
+        b: nestedSchema,
+        c: String
+      }
+    });
+  
+    conn.deleteModel(/Test/);
+    const Parent = conn.model('Test', parentSchema);
+
+    return co(function*() {
+      yield Parent.create({
+        content: {
+          a: { nestedA: 'a' },
+          b: { nestedB: 'b' }
+        }
+      });
+    
+      const doc = yield Parent.findOne();
+
+      const ts = doc.content.b.updatedAt;
+      doc.content.a.nestedA = 'b';
+      yield cb => setTimeout(cb, 10);
+      yield doc.save();
+
+      const fromDb = yield Parent.findById(doc);
+      assert.strictEqual(fromDb.content.b.updatedAt.valueOf(), ts.valueOf());
+    });
+  });
 });

From a8bb2cb6ef3bafb005637f49dfd96fc6aef4d70f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 13:54:41 -0400
Subject: [PATCH 1173/2348] fix(timestamps): don't bump updatedAt in single
 nested subdoc when parent is modifed but subdoc isn't

Re: #9357
---
 lib/document.js                | 2 ++
 lib/types/subdocument.js       | 4 +++-
 test/schema.timestamps.test.js | 4 ++--
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4d496da979c..f91d69a697a 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1855,12 +1855,14 @@ Document.prototype.isModified = function(paths, modifiedPaths) {
     const isModifiedChild = paths.some(function(path) {
       return !!~modified.indexOf(path);
     });
+
     return isModifiedChild || paths.some(function(path) {
       return directModifiedPaths.some(function(mod) {
         return mod === path || path.startsWith(mod + '.');
       });
     });
   }
+
   return this.$__.activePaths.some('modify');
 };
 
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 61b53f0e45e..d6494ffffeb 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -133,9 +133,11 @@ Subdocument.prototype.isModified = function(paths, modifiedPaths) {
     if (Array.isArray(paths) || typeof paths === 'string') {
       paths = (Array.isArray(paths) ? paths : paths.split(' '));
       paths = paths.map(p => [this.$basePath, p].join('.'));
+
+      return this.$parent.isModified(paths, modifiedPaths);
     }
 
-    return this.$parent.isModified(paths, modifiedPaths);
+    return this.$parent.isModified(this.$basePath);
   }
 
   return Document.prototype.isModified.call(this, paths, modifiedPaths);
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index db6e2a1b81c..4c8f7bc0a97 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -419,7 +419,7 @@ describe('schema options.timestamps', function() {
         c: String
       }
     });
-  
+
     conn.deleteModel(/Test/);
     const Parent = conn.model('Test', parentSchema);
 
@@ -430,7 +430,7 @@ describe('schema options.timestamps', function() {
           b: { nestedB: 'b' }
         }
       });
-    
+
       const doc = yield Parent.findOne();
 
       const ts = doc.content.b.updatedAt;

From 533bf37b044a17649ee191a232664271e2e07fd9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 Aug 2020 13:58:13 -0400
Subject: [PATCH 1174/2348] test: clear collection re: #9357

---
 test/schema.timestamps.test.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index 4c8f7bc0a97..ff60cb8f719 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -424,6 +424,8 @@ describe('schema options.timestamps', function() {
     const Parent = conn.model('Test', parentSchema);
 
     return co(function*() {
+      yield Parent.deleteMany({});
+
       yield Parent.create({
         content: {
           a: { nestedA: 'a' },

From f0c53b89e7821ca91c6627991ed82639d284b045 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 29 Aug 2020 12:03:06 -0400
Subject: [PATCH 1175/2348] fix(timestamps): apply timestamps to children if
 update has mixed dollar keys and update keys

Re: #9357
---
 .../update/applyTimestampsToChildren.js       | 12 +++---
 test/schema.timestamps.test.js                | 39 +++++++++++++++++++
 2 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 55b8d1f3161..680d692d02b 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -15,7 +15,7 @@ function applyTimestampsToChildren(now, update, schema) {
   }
 
   const keys = Object.keys(update);
-  const hasDollarKey = keys.length && keys[0].startsWith('$');
+  const hasDollarKey = keys.some(key => key.startsWith('$'));
 
   if (hasDollarKey) {
     if (update.$push) {
@@ -54,11 +54,11 @@ function applyTimestampsToChildren(now, update, schema) {
         applyTimestampsToUpdateKey(schema, key, update.$set, now);
       }
     }
-  } else {
-    const keys = Object.keys(update).filter(key => !key.startsWith('$'));
-    for (const key of keys) {
-      applyTimestampsToUpdateKey(schema, key, update, now);
-    }
+  }
+
+  const updateKeys = Object.keys(update).filter(key => !key.startsWith('$'));
+  for (const key of updateKeys) {
+    applyTimestampsToUpdateKey(schema, key, update, now);
   }
 }
 
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
index ff60cb8f719..17b9e74da54 100644
--- a/test/schema.timestamps.test.js
+++ b/test/schema.timestamps.test.js
@@ -444,4 +444,43 @@ describe('schema options.timestamps', function() {
       assert.strictEqual(fromDb.content.b.updatedAt.valueOf(), ts.valueOf());
     });
   });
+
+  it('bumps updatedAt with mixed $set (gh-9357)', function() {
+    const nestedSchema = Schema({
+      nestedA: { type: String },
+      nestedB: { type: String }
+    }, { timestamps: true });
+    const parentSchema = Schema({
+      content: {
+        a: nestedSchema,
+        b: nestedSchema,
+        c: String
+      }
+    });
+
+    conn.deleteModel(/Test/);
+    const Parent = conn.model('Test', parentSchema);
+
+    return co(function*() {
+      yield Parent.deleteMany({});
+
+      const doc = yield Parent.create({
+        content: {
+          a: { nestedA: 'a' },
+          b: { nestedB: 'b' }
+        }
+      });
+      const ts = doc.content.b.updatedAt;
+
+      yield cb => setTimeout(cb, 10);
+      const fromDb = yield Parent.findOneAndUpdate({}, {
+        'content.c': 'value',
+        $set: {
+          'content.a.nestedA': 'value'
+        }
+      }, { new: true });
+
+      assert.ok(fromDb.content.a.updatedAt.valueOf() > ts.valueOf());
+    });
+  });
 });

From 71abbe1526584d08adcf3ab1b2ef3260d11f38d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 29 Aug 2020 13:23:16 -0400
Subject: [PATCH 1176/2348] fix(schema): support `Schema#add()` with schematype
 instances with different paths

Fix #9370
---
 lib/schema.js       |  4 +++-
 test/schema.test.js | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index d94565e21bb..cbc1e80bd99 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -875,7 +875,9 @@ Object.defineProperty(Schema.prototype, 'base', {
 
 Schema.prototype.interpretAsType = function(path, obj, options) {
   if (obj instanceof SchemaType) {
-    return obj;
+    const clone = obj.clone();
+    clone.path = path;
+    return clone;
   }
 
   // If this schema has an associated Mongoose object, use the Mongoose object's
diff --git a/test/schema.test.js b/test/schema.test.js
index 8b3ceafb214..1664f99d0a9 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2471,4 +2471,28 @@ describe('schema', function() {
 
     assert.equal(schema.path('arr').caster.instance, 'Mixed');
   });
+
+  it('handles using a schematype when defining a path (gh-9370)', function() {
+    const schema1 = Schema({
+      foo: {
+        type: Number,
+        min: 4,
+        get: get
+      }
+    });
+
+    function get(v) {
+      return Math.floor(v);
+    }
+
+    const schema2 = Schema({
+      bar: schema1.path('foo')
+    });
+
+    const schematype = schema2.path('bar');
+    assert.equal(schematype.path, 'bar');
+    assert.equal(schematype.options.type, Number);
+    assert.equal(schematype.options.min, 4);
+    assert.equal(schematype.options.get, get);
+  });
 });

From 4eaa91ff0aae719dfe8a774c5868f99e797cf027 Mon Sep 17 00:00:00 2001
From: elainewlin <elainewlin@gmail.com>
Date: Sat, 29 Aug 2020 16:24:42 -0700
Subject: [PATCH 1177/2348] Fixing documentation for Mongoose Query get

---
 lib/query.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 4bca9b90623..b40b0db58b6 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1757,8 +1757,7 @@ Query.prototype.set = function(path, val) {
  *     const query = Model.updateOne({}, { $set: { name: 'Jean-Luc Picard' } });
  *     query.get('name'); // 'Jean-Luc Picard'
  *
- * @param {String|Object} path path or object of key/value pairs to set
- * @param {Any} [val] the value to set
+ * @param {String|Object} path path or object of key/value pairs to get
  * @return {Query} this
  * @api public
  */

From 63a0a4682072b052a0801c8bb38f40b7285dcaa0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 30 Aug 2020 14:11:25 -0400
Subject: [PATCH 1178/2348] test(populate): repro #9359

---
 test/types.map.test.js | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index aa50f7266a8..a446e72c8b5 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -434,6 +434,42 @@ describe('Map', function() {
         assert.equal(event.scenes.get('bar').name, 'bar');
       });
     });
+
+    it('handles populating path of subdoc (gh-9359)', function() {
+      const bookSchema = Schema({
+        author: {
+          type: 'ObjectId',
+          ref: 'Person'
+        },
+        title: String
+      }, { _id: false });
+
+      const schema = Schema({
+        books: {
+          type: Map,
+          of: bookSchema
+        }
+      });
+
+      const Person = db.model('Person', Schema({ name: String }));
+      const Test = db.model('Test', schema);
+
+      return co(function*() {
+        const person = yield Person.create({ name: 'Ian Fleming' });
+        yield Test.create({
+          books: {
+            key1: {
+              title: 'Casino Royale',
+              author: person._id
+            }
+          }
+        });
+
+        const doc = yield Test.findOne().populate('books.$*.author');
+
+        assert.equal(doc.books.get('key1').author.name, 'Ian Fleming');
+      });
+    });
   });
 
   it('discriminators', function() {

From 743c7f18670a7078712a3f74186b7dc54e3c8089 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 30 Aug 2020 14:11:40 -0400
Subject: [PATCH 1179/2348] fix(populate): allow populating paths underneath
 subdocument maps

Fix #9359
---
 lib/helpers/populate/assignVals.js            |  9 +++++--
 .../populate/getModelsMapForPopulate.js       |  8 +++---
 lib/helpers/populate/lookupLocalFields.js     | 26 +++++++++++++++++++
 3 files changed, 38 insertions(+), 5 deletions(-)
 create mode 100644 lib/helpers/populate/lookupLocalFields.js

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index c47172b0b25..9fd51d80967 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -5,6 +5,7 @@ const assignRawDocsToIdStructure = require('./assignRawDocsToIdStructure');
 const get = require('../get');
 const getVirtual = require('./getVirtual');
 const leanPopulateMap = require('./leanPopulateMap');
+const lookupLocalFields = require('./lookupLocalFields');
 const mpath = require('mpath');
 const sift = require('sift').default;
 const utils = require('../../utils');
@@ -68,7 +69,7 @@ module.exports = function assignVals(o) {
   }
 
   for (let i = 0; i < docs.length; ++i) {
-    const existingVal = utils.getValue(o.path, docs[i]);
+    const existingVal = mpath.get(o.path, docs[i], lookupLocalFields);
     if (existingVal == null && !getVirtual(o.originalModel.schema, o.path)) {
       continue;
     }
@@ -132,6 +133,10 @@ module.exports = function assignVals(o) {
         break;
       }
 
+      if (parts[j] === '$*') {
+        break;
+      }
+
       if (cur[parts[j]] == null) {
         // If nothing to set, avoid creating an unnecessary array. Otherwise
         // we'll end up with a single doc in the array with only defaults.
@@ -156,7 +161,7 @@ module.exports = function assignVals(o) {
     // If lean, need to check that each individual virtual respects
     // `justOne`, because you may have a populated virtual with `justOne`
     // underneath an array. See gh-6867
-    utils.setValue(o.path, valueToSet, docs[i], setValue, false);
+    mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
   }
 };
 
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 0498fc1aa74..2c50401c858 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -7,6 +7,8 @@ const getDiscriminatorByValue = require('../discriminator/getDiscriminatorByValu
 const isPathExcluded = require('../projection/isPathExcluded');
 const getSchemaTypes = require('./getSchemaTypes');
 const getVirtual = require('./getVirtual');
+const lookupLocalFields = require('./lookupLocalFields');
+const mpath = require('mpath');
 const normalizeRefPath = require('./normalizeRefPath');
 const util = require('util');
 const utils = require('../../utils');
@@ -203,16 +205,16 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       options.isVirtual && get(virtual, 'options.getters', false);
     if (localFieldGetters.length > 0 && getters) {
       const hydratedDoc = (doc.$__ != null) ? doc : model.hydrate(doc);
-      const localFieldValue = utils.getValue(localField, doc);
+      const localFieldValue = mpath.get(localField, doc, lookupLocalFields);
       if (Array.isArray(localFieldValue)) {
-        const localFieldHydratedValue = utils.getValue(localField.split('.').slice(0, -1), hydratedDoc);
+        const localFieldHydratedValue = mpath.get(localField.split('.').slice(0, -1), hydratedDoc, lookupLocalFields);
         ret = localFieldValue.map((localFieldArrVal, localFieldArrIndex) =>
           localFieldPath.applyGetters(localFieldArrVal, localFieldHydratedValue[localFieldArrIndex]));
       } else {
         ret = localFieldPath.applyGetters(localFieldValue, hydratedDoc);
       }
     } else {
-      ret = convertTo_id(utils.getValue(localField, doc), schema);
+      ret = convertTo_id(mpath.get(localField, doc, lookupLocalFields), schema);
     }
 
     const id = String(utils.getValue(foreignField, doc));
diff --git a/lib/helpers/populate/lookupLocalFields.js b/lib/helpers/populate/lookupLocalFields.js
new file mode 100644
index 00000000000..08ed7632015
--- /dev/null
+++ b/lib/helpers/populate/lookupLocalFields.js
@@ -0,0 +1,26 @@
+'use strict';
+
+module.exports = function lookupLocalFields(cur, path, val) {
+  if (cur == null) {
+    return cur;
+  }
+
+  if (cur._doc != null) {
+    cur = cur._doc;
+  }
+
+  if (arguments.length >= 3) {
+    cur[path] = val;
+    return val;
+  }
+
+
+  // Support populating paths under maps using `map.$*.subpath`
+  if (path === '$*') {
+    return cur instanceof Map ?
+      Array.from(cur.values()) :
+      Object.keys(cur).map(key => cur[key]);
+  }
+
+  return cur[path];
+};
\ No newline at end of file

From 009b0a36bd30a74bb09482218de51491b6b0438f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 30 Aug 2020 15:15:15 -0400
Subject: [PATCH 1180/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index cb0b8086588..c6113549740 100644
--- a/index.pug
+++ b/index.pug
@@ -361,6 +361,9 @@ html(lang='en')
               <a href="https://onlinecasinoguide.co.nz/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinoguide-co-nz/b16a388/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://casino-academia.com/">
+                <img class="sponsor" src="https://images.opencollective.com/casinoacademia/90fc970/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 7aad624b09c7924ebdfd914b8ea334680ec81446 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 31 Aug 2020 14:47:58 -0400
Subject: [PATCH 1181/2348] test(discriminator): repro #9362

---
 test/model.discriminator.test.js | 34 ++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 0b50a0b6b07..89cd2abae27 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1581,6 +1581,40 @@ describe('model', function() {
     assert.ifError(doc.validateSync());
   });
 
+  it('doesnt remove paths at the same level (gh-9362)', function() {
+    const StepSchema = new Schema({
+      view: {
+        url: {
+          type: String,
+          trim: true
+        }
+      }
+    }, { discriminatorKey: 'type' });
+
+    const ClickSchema = new Schema([
+      StepSchema,
+      {
+        view: {
+          clickCount: {
+            type: Number,
+            default: 1,
+            min: 1
+          }
+        }
+      }
+    ], { discriminatorKey: 'type' });
+
+    const Test = db.model('Test', StepSchema);
+    const D = Test.discriminator('Test1', ClickSchema);
+    assert.ok(D.schema.paths['view.url']);
+
+    const doc = new D({ view: { url: 'google.com' } });
+    assert.ifError(doc.validateSync());
+
+    assert.equal(doc.view.url, 'google.com');
+    assert.equal(doc.view.clickCount, 1);
+  });
+
   it('can use compiled model schema as a discriminator (gh-9238)', function() {
     const SmsSchema = new mongoose.Schema({ senderNumber: String });
     const EmailSchema = new mongoose.Schema({ fromEmailAddress: String });

From 5cd10cf561d17da995d3709244ae601c3e44ced0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 31 Aug 2020 14:48:09 -0400
Subject: [PATCH 1182/2348] fix(discriminator): avoid removing nested path if
 both base and discriminator schema have the same nested path

Fix #9362
---
 lib/helpers/model/discriminator.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index d62840b7c7e..cfacd3d3dfc 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -1,5 +1,6 @@
 'use strict';
 
+const Mixed = require('../../schema/mixed');
 const defineKey = require('../document/compile').defineKey;
 const get = require('../get');
 const utils = require('../../utils');
@@ -89,11 +90,12 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
       if (path.indexOf('.') === -1) {
         continue;
       }
-      const sp = path.split('.');
+      const sp = path.split('.').slice(0, -1);
       let cur = '';
       for (const piece of sp) {
         cur += (cur.length ? '.' : '') + piece;
-        if (schema.paths[cur] || schema.singleNestedPaths[cur]) {
+        if (schema.paths[cur] instanceof Mixed ||
+            schema.singleNestedPaths[cur] instanceof Mixed) {
           conflictingPaths.push(path);
         }
       }

From b7b600ed87f658128bc43042990a8d957d85daeb Mon Sep 17 00:00:00 2001
From: lamhieu-vk <lamhieu.vk@gmail.com>
Date: Thu, 3 Sep 2020 11:02:06 +0700
Subject: [PATCH 1183/2348] chore: update `mongodb` to fix secutiry issue from
 `bl` dependencies

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index a44b35c9fb7..382f7af9baa 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.6.0",
+    "mongodb": "3.6.1",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From 1729a8b82861a9691513dfc5ca448cf29f079fd5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Sep 2020 16:07:51 -0400
Subject: [PATCH 1184/2348] chore: release 5.10.3

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 53c87387fc7..4c196b18b57 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.10.3 / 2020-09-03
+===================
+ * fix: upgrade mongodb -> 3.6.1 #9380 [lamhieu-vk](https://github.com/lamhieu-vk)
+ * fix(populate): allow populating paths underneath subdocument maps #9359
+ * fix(update): handle casting map paths when map is underneath a single nested subdoc #9298
+ * fix(discriminator): avoid removing nested path if both base and discriminator schema have the same nested path #9362
+ * fix(schema): support `Schema#add()` with schematype instances with different paths #9370
+ * docs(api): fix typo in `Query#get()` example #9372 [elainewlin](https://github.com/elainewlin)
+
 5.10.2 / 2020-08-28
 ===================
  * fix(model): avoid uncaught error if `insertMany()` fails due to server selection error #9355
diff --git a/package.json b/package.json
index 382f7af9baa..0e82f9a3c9a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.2",
+  "version": "5.10.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 2854d793bf3ea111e4bd0bce7f2d314219025f57 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Fri, 4 Sep 2020 00:31:30 +0000
Subject: [PATCH 1185/2348] chore(deps-dev): bump marked from 0.6.2 to 1.1.1

Bumps [marked](https://github.com/markedjs/marked) from 0.6.2 to 1.1.1.
- [Release notes](https://github.com/markedjs/marked/releases)
- [Commits](https://github.com/markedjs/marked/compare/v0.6.2...v1.1.1)

Signed-off-by: dependabot[bot] <support@github.com>
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 0e82f9a3c9a..b1c38952c34 100644
--- a/package.json
+++ b/package.json
@@ -50,7 +50,7 @@
     "highlight.js": "9.1.0",
     "lodash.isequal": "4.5.0",
     "lodash.isequalwith": "4.4.0",
-    "marked": "0.6.2",
+    "marked": "1.1.1",
     "mocha": "5.x",
     "moment": "2.x",
     "mongodb-topology-manager": "1.0.11",

From 167402c70fe1e7181835e20574980c568f3086e5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 5 Sep 2020 09:39:55 -0500
Subject: [PATCH 1186/2348] docs(document): fix formatting on `getChanges()`

Fix #9376
---
 lib/document.js | 49 +++++++++++++++++++++++++++++--------------------
 1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f91d69a697a..11217cecc75 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3975,32 +3975,41 @@ Document.prototype.$__fullPath = function(path) {
  * Returns the changes that happened to the document
  * in the format that will be sent to MongoDB.
  *
- *  ###Example:
- *   const userSchema = new Schema({
- *     name: String,
- *     age: Number,
- *     country: String
- *   });
- *   const User = mongoose.model('User', userSchema);
- *   const user = await User.create({
- *     name: 'Hafez',
- *     age: 25,
- *     country: 'Egypt'
- *   });
+ * #### Example:
  *
- *   // returns an empty object, no changes happened yet
- *   user.getChanges(); // { }
+ *     const userSchema = new Schema({
+ *       name: String,
+ *       age: Number,
+ *       country: String
+ *     });
+ *     const User = mongoose.model('User', userSchema);
+ *     const user = await User.create({
+ *       name: 'Hafez',
+ *       age: 25,
+ *       country: 'Egypt'
+ *     });
+ *
+ *     // returns an empty object, no changes happened yet
+ *     user.getChanges(); // { }
+ *
+ *     user.country = undefined;
+ *     user.age = 26;
  *
- *   user.country = undefined;
- *   user.age = 26;
+ *     user.getChanges(); // { $set: { age: 26 }, { $unset: { country: 1 } } }
  *
- *   user.getChanges(); // { $set: { age: 26 }, { $unset: { country: 1 } } }
+ *     await user.save();
  *
- *   await user.save();
+ *     user.getChanges(); // { }
  *
- *   user.getChanges(); // { }
+ * Modifying the object that `getChanges()` returns does not affect the document's
+ * change tracking state. Even if you `delete user.getChanges().$set`, Mongoose
+ * will still send a `$set` to the server.
  *
- * @return {Object} changes
+ * @return {Object}
+ * @api public
+ * @method getChanges
+ * @memberOf Document
+ * @instance
  */
 
 Document.prototype.getChanges = function() {

From dc1af4ffad695fe1a0a2a76258cef260a4eb69f6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 5 Sep 2020 09:45:45 -0500
Subject: [PATCH 1187/2348] chore: fix docs build re: #9384

---
 docs/source/acquit.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/source/acquit.js b/docs/source/acquit.js
index a516cb0c612..126fdb71336 100644
--- a/docs/source/acquit.js
+++ b/docs/source/acquit.js
@@ -75,7 +75,7 @@ files.forEach(function(file) {
     for (var j = 0; j < block.blocks.length; ++j) {
       var b = block.blocks[j];
       b.identifier = toHtmlIdentifier(acquit.trimEachLine(b.contents));
-      b.contents = marked.inlineLexer(acquit.trimEachLine(b.contents), []);
+      b.contents = marked(acquit.trimEachLine(b.contents), []);
       if (b.comments && b.comments.length) {
         var last = b.comments.length - 1;
         b.comments[last] = marked(acquit.trimEachLine(b.comments[last]));

From 6d8d07ea3d021868ebbda3060d65c3ebdab5d578 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E0=B8=8F=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B8=8F=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E=E0=B9=8E?=
 =?UTF-8?q?=E0=B9=8E=E0=B9=8E=E0=B9=8E?= <mdnainar9615@gmail.com>
Date: Sun, 6 Sep 2020 14:30:59 +0530
Subject: [PATCH 1188/2348] replace var with const

---
 docs/guide.pug | 188 ++++++++++++++++++++++++-------------------------
 1 file changed, 93 insertions(+), 95 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 39c021d6682..45d4214a7f2 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -49,10 +49,10 @@ block content
     collection and defines the shape of the documents within that collection.
 
     ```javascript
-      var mongoose = require('mongoose');
-      var Schema = mongoose.Schema;
+      import mongoose from 'mongoose';
+      const { Schema } = mongoose;
 
-      var blogSchema = new Schema({
+      const blogSchema = new Schema({
         title:  String, // String is shorthand for {type: String}
         author: String,
         body:   String,
@@ -118,7 +118,7 @@ block content
     To do so, we pass it into `mongoose.model(modelName, schema)`:
 
     ```javascript
-      var Blog = mongoose.model('Blog', blogSchema);
+      const Blog = mongoose.model('Blog', blogSchema);
       // ready to go!
     ```
 
@@ -167,12 +167,12 @@ block content
 
     ```javascript
       // define a schema
-      var animalSchema = new Schema({ name: String, type: String });
+      const animalSchema = new Schema({ name: String, type: String });
 
       // assign a function to the "methods" object of our animalSchema
-      animalSchema.methods.findSimilarTypes = function(cb) {
-        return mongoose.model('Animal').find({ type: this.type }, cb);
-      };
+      animalSchema.methods.findSimilarTypes = cb => (
+        mongoose.model('Animal').find({ type: this.type }, cb)
+      )
     ```
 
     Now all of our `animal` instances have a `findSimilarTypes` method available
@@ -180,9 +180,9 @@ block content
 
     ```javascript
       var Animal = mongoose.model('Animal', animalSchema);
-      var dog = new Animal({ type: 'dog' });
+      const dog = new Animal({ type: 'dog' });
 
-      dog.findSimilarTypes(function(err, dogs) {
+      dog.findSimilarTypes((err, dogs) => {
         console.log(dogs); // woof
       });
     ```
@@ -201,13 +201,11 @@ block content
 
     ```javascript
       // Assign a function to the "statics" object of our animalSchema
-      animalSchema.statics.findByName = function(name) {
-        return this.find({ name: new RegExp(name, 'i') });
-      };
+      animalSchema.statics.findByName = name => (
+        this.find({ name: new RegExp(name, 'i') });
+       )
       // Or, equivalently, you can call `animalSchema.static()`.
-      animalSchema.static('findByBreed', function(breed) {
-        return this.find({ breed });
-      });
+      animalSchema.static('findByBreed', breed => this.find({ breed }) )
 
       const Animal = mongoose.model('Animal', animalSchema);
       let animals = await Animal.findByName('fido');
@@ -223,17 +221,17 @@ block content
     [chainable query builder API](./queries.html).
 
     ```javascript
-      animalSchema.query.byName = function(name) {
-        return this.where({ name: new RegExp(name, 'i') });
-      };
+      animalSchema.query.byName = name => (
+        this.where({ name: new RegExp(name, 'i') })
+      )
 
-      var Animal = mongoose.model('Animal', animalSchema);
+      const Animal = mongoose.model('Animal', animalSchema);
 
-      Animal.find().byName('fido').exec(function(err, animals) {
+      Animal.find().byName('fido').exec((err, animals) => {
         console.log(animals);
       });
 
-      Animal.findOne().byName('fido').exec(function(err, animal) {
+      Animal.findOne().byName('fido').exec((err, animal) => {
         console.log(animal);
       });
     ```
@@ -246,7 +244,7 @@ block content
     [compound indexes](https://docs.mongodb.com/manual/core/index-compound/).
 
     ```javascript
-      var animalSchema = new Schema({
+      const animalSchema = new Schema({
         name: String,
         type: String,
         tags: { type: [String], index: true } // field level
@@ -277,9 +275,9 @@ block content
       // Will cause an error because mongodb has an _id index by default that
       // is not sparse
       animalSchema.index({ _id: 1 }, { sparse: true });
-      var Animal = mongoose.model('Animal', animalSchema);
+      const Animal = mongoose.model('Animal', animalSchema);
 
-      Animal.on('index', function(error) {
+      Animal.on('index', error => {
         // "_id index cannot be sparse"
         console.log(error.message);
       });
@@ -296,7 +294,7 @@ block content
 
     ```javascript
       // define a schema
-      var personSchema = new Schema({
+      const personSchema = new Schema({
         name: {
           first: String,
           last: String
@@ -304,10 +302,10 @@ block content
       });
 
       // compile our model
-      var Person = mongoose.model('Person', personSchema);
+      const Person = mongoose.model('Person', personSchema);
 
       // create a document
-      var axl = new Person({
+      const axl = new Person({
         name: { first: 'Axl', last: 'Rose' }
       });
     ```
@@ -325,7 +323,7 @@ block content
     define a `fullName` property that won't get persisted to MongoDB.
 
     ```javascript
-    personSchema.virtual('fullName').get(function () {
+    personSchema.virtual('fullName').get(() => {
       return this.name.first + ' ' + this.name.last;
     });
     ```
@@ -348,8 +346,8 @@ block content
 
     ```javascript
     personSchema.virtual('fullName').
-      get(function() { return this.name.first + ' ' + this.name.last; }).
-      set(function(v) {
+      get(() => this.name.first + ' ' + this.name.last).
+      set(v => {
         this.name.first = v.substr(0, v.indexOf(' '));
         this.name.last = v.substr(v.indexOf(' ') + 1);
       });
@@ -372,7 +370,7 @@ block content
     into a longer name for code readability.
 
     ```javascript
-    var personSchema = new Schema({
+    const personSchema = new Schema({
       n: {
         type: String,
         // Now accessing `name` will get you the value of `n`, and setting `n` will set the value of `name`
@@ -381,7 +379,7 @@ block content
     });
 
     // Setting `name` will propagate to `n`
-    var person = new Person({ name: 'Val' });
+    const person = new Person({ name: 'Val' });
     console.log(person); // { n: 'Val' }
     console.log(person.toObject({ virtuals: true })); // { n: 'Val', name: 'Val' }
     console.log(person.name); // "Val"
@@ -409,7 +407,7 @@ block content
 
     // or
 
-    var schema = new Schema({..});
+    const schema = new Schema({..});
     schema.set(option, value);
     ```
 
@@ -500,7 +498,7 @@ block content
     ```javascript
     mongoose.set('bufferCommands', true);
     // Schema option below overrides the above, if the schema option is set.
-    var schema = new Schema({..}, { bufferCommands: false });
+    const schema = new Schema({..}, { bufferCommands: false });
     ```
 
     <h3 id="capped"><a href="#capped">option: capped</a></h3>
@@ -531,7 +529,7 @@ block content
     for your collection.
 
     ```javascript
-    var dataSchema = new Schema({..}, { collection: 'data' });
+    const dataSchema = new Schema({..}, { collection: 'data' });
     ```
 
     <h3 id="id"><a href="#id">option: id</a></h3>
@@ -543,15 +541,15 @@ block content
 
     ```javascript
     // default behavior
-    var schema = new Schema({ name: String });
-    var Page = mongoose.model('Page', schema);
-    var p = new Page({ name: 'mongodb.org' });
+    const schema = new Schema({ name: String });
+    const Page = mongoose.model('Page', schema);
+    const p = new Page({ name: 'mongodb.org' });
     console.log(p.id); // '50341373e894ad16347efe01'
 
     // disabled id
-    var schema = new Schema({ name: String }, { id: false });
+    const schema = new Schema({ name: String }, { id: false });
     var Page = mongoose.model('Page', schema);
-    var p = new Page({ name: 'mongodb.org' });
+    const p = new Page({ name: 'mongodb.org' });
     console.log(p.id); // undefined
     ```
 
@@ -569,18 +567,18 @@ block content
 
     ```javascript
     // default behavior
-    var schema = new Schema({ name: String });
-    var Page = mongoose.model('Page', schema);
-    var p = new Page({ name: 'mongodb.org' });
+    const schema = new Schema({ name: String });
+    const Page = mongoose.model('Page', schema);
+    const p = new Page({ name: 'mongodb.org' });
     console.log(p); // { _id: '50341373e894ad16347efe01', name: 'mongodb.org' }
 
     // disabled _id
-    var childSchema = new Schema({ name: String }, { _id: false });
-    var parentSchema = new Schema({ children: [childSchema] });
+    const childSchema = new Schema({ name: String }, { _id: false });
+    const parentSchema = new Schema({ children: [childSchema] });
 
-    var Model = mongoose.model('Model', parentSchema);
+    const Model = mongoose.model('Model', parentSchema);
 
-    Model.create({ children: [{ name: 'Luke' }] }, function(error, doc) {
+    Model.create({ children: [{ name: 'Luke' }] }, (error, doc) => {
       // doc.children[0]._id will be undefined
     });
     ```
@@ -638,11 +636,11 @@ block content
     to all queries derived from a model.
 
     ```javascript
-    var schema = new Schema({..}, { read: 'primary' });            // also aliased as 'p'
-    var schema = new Schema({..}, { read: 'primaryPreferred' });   // aliased as 'pp'
-    var schema = new Schema({..}, { read: 'secondary' });          // aliased as 's'
-    var schema = new Schema({..}, { read: 'secondaryPreferred' }); // aliased as 'sp'
-    var schema = new Schema({..}, { read: 'nearest' });            // aliased as 'n'
+    const schema = new Schema({..}, { read: 'primary' });            // also aliased as 'p'
+    const schema = new Schema({..}, { read: 'primaryPreferred' });   // aliased as 'pp'
+    const schema = new Schema({..}, { read: 'secondary' });          // aliased as 's'
+    const schema = new Schema({..}, { read: 'secondaryPreferred' }); // aliased as 'sp'
+    const schema = new Schema({..}, { read: 'nearest' });            // aliased as 'n'
     ```
 
     The alias of each pref is also permitted so instead of having to type out
@@ -659,10 +657,10 @@ block content
 
     ```javascript
     // pings the replset members periodically to track network latency
-    var options = { replset: { strategy: 'ping' }};
+    const options = { replset: { strategy: 'ping' }};
     mongoose.connect(uri, options);
 
-    var schema = new Schema({..}, { read: ['nearest', { disk: 'ssd' }] });
+    const schema = new Schema({..}, { read: ['nearest', { disk: 'ssd' }] });
     mongoose.model('JellyBean', schema);
     ```
 
@@ -702,23 +700,23 @@ block content
     the db.
 
     ```javascript
-    var thingSchema = new Schema({..})
-    var Thing = mongoose.model('Thing', thingSchema);
-    var thing = new Thing({ iAmNotInTheSchema: true });
+    const thingSchema = new Schema({..})
+    const Thing = mongoose.model('Thing', thingSchema);
+    const thing = new Thing({ iAmNotInTheSchema: true });
     thing.save(); // iAmNotInTheSchema is not saved to the db
 
     // set to false..
-    var thingSchema = new Schema({..}, { strict: false });
-    var thing = new Thing({ iAmNotInTheSchema: true });
+    const thingSchema = new Schema({..}, { strict: false });
+    const thing = new Thing({ iAmNotInTheSchema: true });
     thing.save(); // iAmNotInTheSchema is now saved to the db!!
     ```
 
     This also affects the use of `doc.set()` to set a property value.
 
     ```javascript
-    var thingSchema = new Schema({..})
-    var Thing = mongoose.model('Thing', thingSchema);
-    var thing = new Thing;
+    const thingSchema = new Schema({..})
+    const Thing = mongoose.model('Thing', thingSchema);
+    const thing = new Thing;
     thing.set('iAmNotInTheSchema', true);
     thing.save(); // iAmNotInTheSchema is not saved to the db
     ```
@@ -727,9 +725,9 @@ block content
     boolean argument:
 
     ```javascript
-    var Thing = mongoose.model('Thing');
-    var thing = new Thing(doc, true);  // enables strict mode
-    var thing = new Thing(doc, false); // disables strict mode
+    const Thing = mongoose.model('Thing');
+    const thing = new Thing(doc, true);  // enables strict mode
+    const thing = new Thing(doc, false); // disables strict mode
     ```
 
     The `strict` option may also be set to `"throw"` which will cause errors
@@ -739,9 +737,9 @@ block content
     is always ignored, regardless of schema option._
 
     ```javascript
-    var thingSchema = new Schema({..})
-    var Thing = mongoose.model('Thing', thingSchema);
-    var thing = new Thing;
+    const thingSchema = new Schema({..})
+    const Thing = mongoose.model('Thing', thingSchema);
+    const thing = new Thing;
     thing.iAmNotInTheSchema = true;
     thing.save(); // iAmNotInTheSchema is never saved to the db
     ```
@@ -787,13 +785,13 @@ block content
     the document's `toJSON` method is called.
 
     ```javascript
-    var schema = new Schema({ name: String });
+    const schema = new Schema({ name: String });
     schema.path('name').get(function (v) {
       return v + ' is my name';
     });
     schema.set('toJSON', { getters: true, virtuals: false });
-    var M = mongoose.model('Person', schema);
-    var m = new M({ name: 'Max Headroom' });
+    const M = mongoose.model('Person', schema);
+    const m = new M({ name: 'Max Headroom' });
     console.log(m.toObject()); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom' }
     console.log(m.toJSON()); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }
     // since we know toJSON is called whenever a js object is stringified:
@@ -814,13 +812,13 @@ block content
     `toObject` option to `{ getters: true }`:
 
     ```javascript
-    var schema = new Schema({ name: String });
-    schema.path('name').get(function (v) {
+    const schema = new Schema({ name: String });
+    schema.path('name').get(v => {
       return v + ' is my name';
     });
     schema.set('toObject', { getters: true });
-    var M = mongoose.model('Person', schema);
-    var m = new M({ name: 'Max Headroom' });
+    const M = mongoose.model('Person', schema);
+    const m = new M({ name: 'Max Headroom' });
     console.log(m); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }
     ```
 
@@ -833,7 +831,7 @@ block content
 
     ```javascript
     // Mongoose interprets this as 'loc is a String'
-    var schema = new Schema({ loc: { type: String, coordinates: [Number] } });
+    const schema = new Schema({ loc: { type: String, coordinates: [Number] } });
     ```
 
     However, for applications like [geoJSON](http://docs.mongodb.org/manual/reference/geojson/),
@@ -841,7 +839,7 @@ block content
     uses to find type declarations, set the 'typeKey' schema option.
 
     ```javascript
-    var schema = new Schema({
+    const schema = new Schema({
       // Mongoose interpets this as 'loc is an object with 2 keys, type and coordinates'
       loc: { type: String, coordinates: [Number] },
       // Mongoose interprets this as 'name is a String'
@@ -857,13 +855,13 @@ block content
     validation, you can set `validateBeforeSave` to false.
 
     ```javascript
-    var schema = new Schema({ name: String });
+    const schema = new Schema({ name: String });
     schema.set('validateBeforeSave', false);
     schema.path('name').validate(function (value) {
         return value != null;
     });
-    var M = mongoose.model('Person', schema);
-    var m = new M({ name: null });
+    const M = mongoose.model('Person', schema);
+    const m = new M({ name: null });
     m.validate(function(err) {
         console.log(err); // Will tell you that null is not allowed.
     });
@@ -1018,17 +1016,17 @@ block content
     for every query and aggregation. [Here's a beginner-friendly overview of collations](http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations).
 
     ```javascript
-    var schema = new Schema({
+    const schema = new Schema({
       name: String
     }, { collation: { locale: 'en_US', strength: 1 } });
 
-    var MyModel = db.model('MyModel', schema);
+    const MyModel = db.model('MyModel', schema);
 
     MyModel.create([{ name: 'val' }, { name: 'Val' }]).
-      then(function() {
+      then(() => {
         return MyModel.find({ name: 'val' });
       }).
-      then(function(docs) {
+      then((docs) => {
         // `docs` will contain both docs, because `strength: 1` means
         // MongoDB will ignore case when matching.
       });
@@ -1114,31 +1112,31 @@ block content
     schema's strict mode setting.
 
     ```javascript
-    var childSchema = new Schema({}, { strict: false });
-    var parentSchema = new Schema({ child: childSchema }, { strict: 'throw' });
-    var Parent = mongoose.model('Parent', parentSchema);
-    Parent.update({}, { 'child.name': 'Luke Skywalker' }, function(error) {
+    const childSchema = new Schema({}, { strict: false });
+    const parentSchema = new Schema({ child: childSchema }, { strict: 'throw' });
+    const Parent = mongoose.model('Parent', parentSchema);
+    Parent.update({}, { 'child.name': 'Luke Skywalker' }, (error) => {
       // Error because parentSchema has `strict: throw`, even though
       // `childSchema` has `strict: false`
     });
 
-    var update = { 'child.name': 'Luke Skywalker' };
-    var opts = { strict: false };
+    const update = { 'child.name': 'Luke Skywalker' };
+    const opts = { strict: false };
     Parent.update({}, update, opts, function(error) {
       // This works because passing `strict: false` to `update()` overwrites
       // the parent schema.
     });
     ```
 
-    If you set `useNestedStrict` to true, mongoose will use the child schema's
+    If you set `useNconstestedStrict` to true, mongoose will use the child schema's
     `strict` option for casting updates.
 
     ```javascript
-    var childSchema = new Schema({}, { strict: false });
+    const childSchema = new Schema({}, { strict: false });
     var parentSchema = new Schema({ child: childSchema },
       { strict: 'throw', useNestedStrict: true });
-    var Parent = mongoose.model('Parent', parentSchema);
-    Parent.update({}, { 'child.name': 'Luke Skywalker' }, function(error) {
+    const Parent = mongoose.model('Parent', parentSchema);
+    Parent.update({}, { 'child.name': 'Luke Skywalker' }, error => {
       // Works!
     });
     ```

From 3261852a30e8159767dbe2f89c0affb7564c1dc1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 6 Sep 2020 10:37:45 -0500
Subject: [PATCH 1189/2348] fix: handle `findOneAndRemove()` with `orFail()`

Fix #9381
---
 lib/query.js                        |  1 +
 test/model.findOneAndRemove.test.js | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/query.js b/lib/query.js
index b40b0db58b6..190bf56c5f7 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4301,6 +4301,7 @@ Query.prototype.orFail = function(err) {
         }
         break;
       case 'findOneAndDelete':
+      case 'findOneAndRemove':
         if (get(res, 'lastErrorObject.n') === 0) {
           throw _orFailError(err, this);
         }
diff --git a/test/model.findOneAndRemove.test.js b/test/model.findOneAndRemove.test.js
index d7a34b3b71b..5129d57d64c 100644
--- a/test/model.findOneAndRemove.test.js
+++ b/test/model.findOneAndRemove.test.js
@@ -347,6 +347,17 @@ describe('model: findOneAndRemove:', function() {
     });
   });
 
+  it('with orFail() (gh-9381)', function() {
+    const User = db.model('User', Schema({ name: String }));
+
+    return User.findOneAndRemove({ name: 'not found' }).orFail().
+      then(() => null, err => err).
+      then(err => {
+        assert.ok(err);
+        assert.equal(err.name, 'DocumentNotFoundError');
+      });
+  });
+
   describe('middleware', function() {
     it('works', function(done) {
       const s = new Schema({

From 1b19af2ed50a9c25d1cd1f4c3112a18b1059402b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Sep 2020 16:32:47 -0400
Subject: [PATCH 1190/2348] test(schema): repro #9390

---
 test/schema.test.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 1664f99d0a9..912340efd56 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -739,11 +739,17 @@ describe('schema', function() {
       }, { _id: true });
       assert.ok(schema.path('_id') instanceof Schema.ObjectId);
 
+      schema.set('_id', false);
+      assert.ok(schema.path('_id') == null);
+
       schema = new Schema({
         name: String
       }, { _id: false });
       assert.equal(schema.path('_id'), undefined);
 
+      schema.set('_id', true);
+      assert.ok(schema.path('_id') instanceof Schema.ObjectId);
+
       // old options
       schema = new Schema({
         name: String

From 31ad004b64bff002cc8e3b918422ba9e157dc1d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Sep 2020 16:37:24 -0400
Subject: [PATCH 1191/2348] fix(schema): support setting `_id` option to
 `false` after instantiating schema

Fix #9390
---
 lib/schema.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index cbc1e80bd99..72410395747 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1656,6 +1656,16 @@ Schema.prototype.set = function(key, value, _tags) {
       this.options[key] = value;
       this._userProvidedOptions[key] = this.options[key];
       break;
+    case '_id':
+      this.options[key] = value;
+      this._userProvidedOptions[key] = this.options[key];
+
+      if (value && !this.paths['_id']) {
+        addAutoId(this);
+      } else if (!value && this.paths['_id'] != null && this.paths['_id'].auto) {
+        this.remove('_id');
+      }
+      break;
     default:
       this.options[key] = value;
       this._userProvidedOptions[key] = this.options[key];

From 61885f246b77740c6acd412838fcb75d31369e87 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Sep 2020 10:04:39 -0400
Subject: [PATCH 1192/2348] test(document): repro #9392

---
 test/document.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 15c5b9097ca..e58c8f9a5fd 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9311,4 +9311,18 @@ describe('document', function() {
       assert.equal(fromDb.children.length, 0);
     });
   });
+
+  it('allows setting nested path to instance of model (gh-9392)', function() {
+    const def = { test: String };
+    const Child = db.model('Child', def);
+
+    const Parent = db.model('Parent', { nested: def });
+
+    const c = new Child({ test: 'new' });
+
+    const p = new Parent({ nested: { test: 'old' } });
+    p.nested = c;
+
+    assert.equal(p.nested.test, 'new');
+  });
 });

From c5294c3a211524a95c34ae8104cdfd83f3c32b91 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Sep 2020 10:05:19 -0400
Subject: [PATCH 1193/2348] fix(document): allow setting nested path to
 instance of model

Fix #9392
---
 lib/helpers/document/compile.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index 0868f24516c..1a2a0357d8b 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -2,6 +2,7 @@
 
 const documentSchemaSymbol = require('../../helpers/symbols').documentSchemaSymbol;
 const get = require('../../helpers/get');
+const internalToObjectOptions = require('../../options').internalToObjectOptions;
 const utils = require('../../utils');
 
 let Document;
@@ -142,6 +143,8 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
           // Convert top-level to POJO, but leave subdocs hydrated so `$set`
           // can handle them. See gh-9293.
           v = v.$__parent.get(path);
+        } else if (v instanceof Document && !v.$__isNested) {
+          v = v.toObject(internalToObjectOptions);
         }
         const doc = this.$__[scopeSymbol] || this;
         doc.$set(path, v);

From 7d3f9fe4c451aea5065653cb0455049709f9ca18 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Sep 2020 10:42:27 -0400
Subject: [PATCH 1194/2348] chore: release 5.10.4

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 4c196b18b57..63ffaf1cd2e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.10.4 / 2020-09-09
+===================
+ * fix(document): allow setting nested path to instance of model #9392
+ * fix: handle `findOneAndRemove()` with `orFail()` #9381
+ * fix(schema): support setting `_id` option to `false` after instantiating schema #9390
+ * docs(document): fix formatting on `getChanges()` #9376
+
 5.10.3 / 2020-09-03
 ===================
  * fix: upgrade mongodb -> 3.6.1 #9380 [lamhieu-vk](https://github.com/lamhieu-vk)
diff --git a/package.json b/package.json
index b1c38952c34..dcbdb75203e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.3",
+  "version": "5.10.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 42f99cfc8a28f11aceca7791a77dca960f286ac1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Sep 2020 10:46:34 -0400
Subject: [PATCH 1195/2348] chore: add travis and webpack configs to npmignore

---
 .npmignore | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.npmignore b/.npmignore
index fce500a605e..69deea027ae 100644
--- a/.npmignore
+++ b/.npmignore
@@ -34,3 +34,6 @@ website.js
 
 migrating_to_5.md
 renovate.json
+.travis.yml
+webpack.config.js
+webpack.base.config.js

From b002f310c52a1e75b52f0d37911e077beb8cf665 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Sep 2020 17:55:51 -0400
Subject: [PATCH 1196/2348] chore: start working on typescript definitions re:
 #8108

---
 index.d.ts        | 50 +++++++++++++++++++++++++++++++++++++++++++++++
 lib/connection.js |  1 +
 lib/index.js      |  3 ++-
 lib/model.js      |  2 +-
 4 files changed, 54 insertions(+), 2 deletions(-)
 create mode 100644 index.d.ts

diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 00000000000..165097a60d6
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,50 @@
+declare module "mongoose" {
+  import mongodb = require('mongodb');
+  import mongoose = require('mongoose');
+
+  export function connect(uri: string, options: ConnectOptions, callback: (err: Error) => void): void;
+  export function connect(uri: string, callback: (err: Error) => void): void;
+  export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
+
+  export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
+
+  type Mongoose = typeof mongoose;
+
+  interface ConnectOptions extends mongodb.MongoClientOptions {
+    /** Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection. */
+    bufferCommands?: boolean;
+    /** The name of the database you want to use. If not provided, Mongoose uses the database name from connection string. */
+    dbName?: string;
+    /** username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility. */
+    user?: string;
+    /** password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility. */
+    pass?: string;
+    /** Set to false to disable automatic index creation for all models associated with this connection. */
+    autoIndex?: boolean;
+    /** True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`. */
+    useFindAndModify?: boolean;
+    /** Set to `true` to make Mongoose automatically call `createCollection()` on every model created on this connection. */
+    autoCreate?: boolean;
+  }
+
+  class Document {}
+
+  class Model<T> extends Document {
+    constructor(obj?: any);
+  }
+
+  class Schema {
+    /**
+     * Create a new schema
+     */
+    constructor(definition?: SchemaDefinition);
+  }
+
+  interface SchemaDefinition {
+    [path: string]: SchemaTypeOptions<any>
+  }
+
+  interface SchemaTypeOptions<T> {
+    type?: T;
+  }
+}
\ No newline at end of file
diff --git a/lib/connection.js b/lib/connection.js
index 106103ce01e..0f623660385 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -629,6 +629,7 @@ Connection.prototype.onOpen = function() {
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
  * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
+ * @param {Boolean} [options.autoCreate=false] Set to `true` to make Mongoose automatically call `createCollection()` on every model created on this connection.
  * @param {Function} [callback]
  * @returns {Connection} this
  * @api public
diff --git a/lib/index.js b/lib/index.js
index 5ac7c9a949e..15e83422b26 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -249,7 +249,7 @@ Mongoose.prototype.get = Mongoose.prototype.set;
  * @param {String} [uri] a mongodb:// URI
  * @param {Object} [options] passed down to the [MongoDB driver's `connect()` function](http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html), except for 4 mongoose-specific options explained below.
  * @param {Boolean} [options.bufferCommands=true] Mongoose specific option. Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection.
- * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
+ * @param {String} [options.dbName] The name of the database you want to use. If not provided, Mongoose uses the database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
@@ -327,6 +327,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {Number} [options.connectTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
  * @param {Number} [options.socketTimeoutMS=30000] How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
  * @param {Number} [options.family=0] Passed transparently to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. May be either `0`, `4`, or `6`. `4` means use IPv4 only, `6` means use IPv6 only, `0` means try both.
+ * @param {Boolean} [options.autoCreate=false] Set to `true` to make Mongoose automatically call `createCollection()` on every model created on this connection.
  * @param {Function} [callback]
  * @see Mongoose#createConnection #index_Mongoose-createConnection
  * @api public
diff --git a/lib/model.js b/lib/model.js
index 84b4220bd3d..6cc3869e9e0 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -423,7 +423,7 @@ function generateVersionError(doc, modifiedPaths) {
 
 /**
  * Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`,
- * or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation **only** with the modifications to the database, it does not replace the whole document in the latter case.
+ * or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`.
  *
  * ####Example:
  *

From 63fcb045a54fcf2465d26af3f0b81be934613c24 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Sep 2020 12:19:32 -0400
Subject: [PATCH 1197/2348] feat(document+model): make change tracking skip
 saving if new value matches last saved value

Fix #9396
---
 lib/document.js       | 25 ++++++++++++++++++-
 lib/model.js          |  1 +
 test/document.test.js | 58 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 83 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 11217cecc75..2464b7e7ff0 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1021,6 +1021,16 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
   if (pathType === 'nested' && val) {
     if (typeof val === 'object' && val != null) {
+      const hasPriorVal = this.$__.savedState != null && this.$__.savedState.hasOwnProperty(path);
+      if (this.$__.savedState != null && !this.isNew && !this.$__.savedState.hasOwnProperty(path)) {
+        this.$__.savedState[path] = this.$__getValue(path);
+
+        const keys = Object.keys(this.$__.savedState[path]);
+        for (const key of keys) {
+          this.$__.savedState[path + '.' + key] = this.$__.savedState[path][key];
+        }
+      }
+
       if (!merge) {
         this.$__setValue(path, null);
         cleanModifiedSubpaths(this, path);
@@ -1033,7 +1043,12 @@ Document.prototype.$set = function $set(path, val, type, options) {
       for (const key of keys) {
         this.$set(path + '.' + key, val[key], constructing);
       }
-      this.markModified(path);
+
+      if (hasPriorVal && utils.deepEqual(this.$__.savedState[path], val)) {
+        this.unmarkModified(path);
+      } else {
+        this.markModified(path);
+      }
       cleanModifiedSubpaths(this, path, { skipDocArrays: true });
       return this;
     }
@@ -1279,6 +1294,14 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
   if (shouldSet) {
     this.$__set(pathToMark, path, constructing, parts, schema, val, priorVal);
+
+    if (this.$__.savedState != null) {
+      if (!this.isNew && !this.$__.savedState.hasOwnProperty(path)) {
+        this.$__.savedState[path] = priorVal;
+      } else if (this.$__.savedState.hasOwnProperty(path) && utils.deepEqual(val, this.$__.savedState[path])) {
+        this.unmarkModified(path);
+      }
+    }
   }
 
   if (schema.$isSingleNested && (this.isDirectModified(path) || val == null)) {
diff --git a/lib/model.js b/lib/model.js
index 84b4220bd3d..6ea40f5ba1f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -402,6 +402,7 @@ Model.prototype.$__save = function(options, callback) {
       }
     }
     this.$__.saving = undefined;
+    this.$__.savedState = {};
     this.emit('save', this, numAffected);
     this.constructor.emit('save', this, numAffected);
     callback(null, this);
diff --git a/test/document.test.js b/test/document.test.js
index e58c8f9a5fd..3ff19a18e14 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9325,4 +9325,62 @@ describe('document', function() {
 
     assert.equal(p.nested.test, 'new');
   });
+
+  it('unmarks modified if setting a value to the same value as it was previously (gh-9396)', function() {
+    const schema = new Schema({
+      bar: String
+    });
+
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const foo = new Test({ bar: 'bar' });
+      yield foo.save();
+      assert.ok(!foo.isModified('bar'));
+
+      foo.bar = 'baz';
+      assert.ok(foo.isModified('bar'));
+
+      foo.bar = 'bar';
+      assert.ok(!foo.isModified('bar'));
+    });
+  });
+
+  it('unmarks modified if setting a value to the same subdoc as it was previously (gh-9396)', function() {
+    const schema = new Schema({
+      nested: { bar: String },
+      subdoc: new Schema({ bar: String }, { _id: false })
+    });
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const foo = new Test({ nested: { bar: 'bar' }, subdoc: { bar: 'bar' } });
+      yield foo.save();
+      assert.ok(!foo.isModified('nested'));
+      assert.ok(!foo.isModified('subdoc'));
+
+      foo.nested = { bar: 'baz' };
+      foo.subdoc = { bar: 'baz' };
+      assert.ok(foo.isModified('nested'));
+      assert.ok(foo.isModified('subdoc'));
+
+      foo.nested = { bar: 'bar' };
+      foo.subdoc = { bar: 'bar' };
+      assert.ok(!foo.isModified('nested'));
+      assert.ok(!foo.isModified('subdoc'));
+      assert.ok(!foo.isModified('subdoc.bar'));
+
+      foo.nested = { bar: 'baz' };
+      foo.subdoc = { bar: 'baz' };
+      assert.ok(foo.isModified('nested'));
+      assert.ok(foo.isModified('subdoc'));
+      yield foo.save();
+
+      foo.nested = { bar: 'bar' };
+      foo.subdoc = { bar: 'bar' };
+      assert.ok(foo.isModified('nested'));
+      assert.ok(foo.isModified('subdoc'));
+      assert.ok(foo.isModified('subdoc.bar'));
+    });
+  });
 });

From db0562821bbef287f1ebcd65d8a1a9b2e808c885 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Sep 2020 14:26:42 -0400
Subject: [PATCH 1198/2348] fix(query+aggregate+cursor): support async
 iteration over a cursor instance as opposed to a Query or Aggregate instance

Fix #9403
---
 lib/aggregate.js                       |  6 +--
 lib/cursor/AggregationCursor.js        | 58 ++++++++++++++++++++++++++
 lib/cursor/QueryCursor.js              | 55 ++++++++++++++++++++++++
 lib/helpers/clone.js                   |  1 +
 lib/query.js                           |  6 +--
 test/es-next/asyncIterator.test.es6.js | 30 ++++++++++++-
 6 files changed, 147 insertions(+), 9 deletions(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index bc53742bd8f..ed15c584dfb 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -1054,7 +1054,7 @@ Aggregate.prototype.catch = function(reject) {
 };
 
 /**
- * Returns an asyncIterator for use with [`for/await/of` loops](http://bit.ly/async-iterators)
+ * Returns an asyncIterator for use with [`for/await/of` loops](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js
  * You do not need to call this function explicitly, the JavaScript runtime
  * will call it for you.
  *
@@ -1083,9 +1083,7 @@ if (Symbol.asyncIterator != null) {
     return this.cursor({ useMongooseAggCursor: true }).
       exec().
       transformNull().
-      map(doc => {
-        return doc == null ? { done: true } : { value: doc, done: false };
-      });
+      _transformForAsyncIterator();
   };
 }
 
diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 9137a88e93b..71a13538f22 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -221,6 +221,56 @@ AggregationCursor.prototype.eachAsync = function(fn, opts, callback) {
   return eachAsync(function(cb) { return _next(_this, cb); }, fn, opts, callback);
 };
 
+/**
+ * Returns an asyncIterator for use with [`for/await/of` loops](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js
+ * You do not need to call this function explicitly, the JavaScript runtime
+ * will call it for you.
+ *
+ * ####Example
+ *
+ *     // Async iterator without explicitly calling `cursor()`. Mongoose still
+ *     // creates an AggregationCursor instance internally.
+ *     const agg = Model.aggregate([{ $match: { age: { $gte: 25 } } }]);
+ *     for await (const doc of agg) {
+ *       console.log(doc.name);
+ *     }
+ *
+ *     // You can also use an AggregationCursor instance for async iteration
+ *     const cursor = Model.aggregate([{ $match: { age: { $gte: 25 } } }]).cursor();
+ *     for await (const doc of cursor) {
+ *       console.log(doc.name);
+ *     }
+ *
+ * Node.js 10.x supports async iterators natively without any flags. You can
+ * enable async iterators in Node.js 8.x using the [`--harmony_async_iteration` flag](https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187).
+ *
+ * **Note:** This function is not set if `Symbol.asyncIterator` is undefined. If
+ * `Symbol.asyncIterator` is undefined, that means your Node.js version does not
+ * support async iterators.
+ *
+ * @method Symbol.asyncIterator
+ * @memberOf AggregationCursor
+ * @instance
+ * @api public
+ */
+
+if (Symbol.asyncIterator != null) {
+  AggregationCursor.prototype[Symbol.asyncIterator] = function() {
+    return this.transformNull()._transformForAsyncIterator();
+  };
+}
+
+/*!
+ * ignore
+ */
+
+AggregationCursor.prototype._transformForAsyncIterator = function() {
+  if (this._transforms.indexOf(_transformForAsyncIterator) === -1) {
+    this.map(_transformForAsyncIterator);
+  }
+  return this;
+};
+
 /*!
  * ignore
  */
@@ -233,6 +283,14 @@ AggregationCursor.prototype.transformNull = function(val) {
   return this;
 };
 
+/*!
+ * ignore
+ */
+
+function _transformForAsyncIterator(doc) {
+  return doc == null ? { done: true } : { value: doc, done: false };
+}
+
 /**
  * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
  * Useful for setting the `noCursorTimeout` and `tailable` flags.
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index a77f5bb472a..656cd4a5bf2 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -270,6 +270,61 @@ QueryCursor.prototype.transformNull = function(val) {
   return this;
 };
 
+/*!
+ * ignore
+ */
+
+QueryCursor.prototype._transformForAsyncIterator = function() {
+  if (this._transforms.indexOf(_transformForAsyncIterator) === -1) {
+    this.map(_transformForAsyncIterator);
+  }
+  return this;
+};
+
+/**
+ * Returns an asyncIterator for use with [`for/await/of` loops](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js).
+ * You do not need to call this function explicitly, the JavaScript runtime
+ * will call it for you.
+ *
+ * ####Example
+ *
+ *     // Works without using `cursor()`
+ *     for await (const doc of Model.find([{ $sort: { name: 1 } }])) {
+ *       console.log(doc.name);
+ *     }
+ *
+ *     // Can also use `cursor()`
+ *     for await (const doc of Model.find([{ $sort: { name: 1 } }]).cursor()) {
+ *       console.log(doc.name);
+ *     }
+ *
+ * Node.js 10.x supports async iterators natively without any flags. You can
+ * enable async iterators in Node.js 8.x using the [`--harmony_async_iteration` flag](https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187).
+ *
+ * **Note:** This function is not if `Symbol.asyncIterator` is undefined. If
+ * `Symbol.asyncIterator` is undefined, that means your Node.js version does not
+ * support async iterators.
+ *
+ * @method Symbol.asyncIterator
+ * @memberOf Query
+ * @instance
+ * @api public
+ */
+
+if (Symbol.asyncIterator != null) {
+  QueryCursor.prototype[Symbol.asyncIterator] = function() {
+    return this.transformNull()._transformForAsyncIterator();
+  };
+}
+
+/*!
+ * ignore
+ */
+
+function _transformForAsyncIterator(doc) {
+  return doc == null ? { done: true } : { value: doc, done: false };
+}
+
 /*!
  * Get the next doc from the underlying cursor and mongooseify it
  * (populate, etc.)
diff --git a/lib/helpers/clone.js b/lib/helpers/clone.js
index 1d53776f368..c93a17fbdf2 100644
--- a/lib/helpers/clone.js
+++ b/lib/helpers/clone.js
@@ -41,6 +41,7 @@ function clone(obj, options, isArrayChild) {
     if (options && options._skipSingleNestedGetters && obj.$isSingleNested) {
       options = Object.assign({}, options, { getters: false });
     }
+
     if (options && options.json && typeof obj.toJSON === 'function') {
       return obj.toJSON(options);
     }
diff --git a/lib/query.js b/lib/query.js
index 190bf56c5f7..a2816f8e46b 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -5168,7 +5168,7 @@ Query.prototype.nearSphere = function() {
 };
 
 /**
- * Returns an asyncIterator for use with [`for/await/of` loops](http://bit.ly/async-iterators)
+ * Returns an asyncIterator for use with [`for/await/of` loops](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js)
  * This function *only* works for `find()` queries.
  * You do not need to call this function explicitly, the JavaScript runtime
  * will call it for you.
@@ -5194,9 +5194,7 @@ Query.prototype.nearSphere = function() {
 
 if (Symbol.asyncIterator != null) {
   Query.prototype[Symbol.asyncIterator] = function() {
-    return this.cursor().transformNull().map(doc => {
-      return doc == null ? { done: true } : { value: doc, done: false };
-    });
+    return this.cursor().transformNull()._transformForAsyncIterator();
   };
 }
 
diff --git a/test/es-next/asyncIterator.test.es6.js b/test/es-next/asyncIterator.test.es6.js
index 24cc785a146..e622e1b96a4 100644
--- a/test/es-next/asyncIterator.test.es6.js
+++ b/test/es-next/asyncIterator.test.es6.js
@@ -32,18 +32,46 @@ describe('asyncIterator', function() {
     db.close(done);
   });
 
+  function wait() {
+    return new Promise(resolve => setTimeout(resolve, 0));
+  }
+
   it('supports for/await/of on a query (gh-6737)', async function() {
     let names = [];
     for await (const doc of Movie.find().sort({ name: 1 })) {
+      await wait();
       names.push(doc.name);
     }
 
     assert.deepEqual(names, ['Enter the Dragon', 'Ip Man', 'Kickboxer']);
   });
 
-  it('supports for/await/of on a query (gh-6737)', async function() {
+  it('supports for/await/of on a aggregation (gh-6737)', async function() {
     let names = [];
     for await (const doc of Movie.aggregate([{ $sort: { name: -1 } }])) {
+      await wait();
+      names.push(doc.name);
+    }
+
+    assert.deepEqual(names, ['Kickboxer', 'Ip Man', 'Enter the Dragon']);
+  });
+
+  it('supports for/await/of on a query cursor (gh-9403)', async function() {
+    let names = [];
+    const cursor = Movie.find().sort({ name: -1 }).cursor();
+    for await (const doc of cursor) {
+      await wait();
+      names.push(doc.name);
+    }
+
+    assert.deepEqual(names, ['Kickboxer', 'Ip Man', 'Enter the Dragon']);
+  });
+
+  it('supports for/await/of on a aggregation cursor (gh-9403)', async function() {
+    let names = [];
+    const cursor = Movie.aggregate([{ $sort: { name: -1 } }]).cursor();
+    for await (const doc of cursor) {
+      await wait();
       names.push(doc.name);
     }
 

From 57a015a5f7b9b57211e6bf8e6200e2fa282ccd36 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Sep 2020 15:01:02 -0400
Subject: [PATCH 1199/2348] test(document): repro #9405

---
 test/document.test.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index e58c8f9a5fd..0b7af49daee 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -774,6 +774,35 @@ describe('document', function() {
         });
       });
     });
+
+    it('respects child schemas minimize (gh-9405)', function() {
+      const postSchema = new Schema({
+        owner: { type: Schema.Types.ObjectId, ref: 'User' },
+        props: { type: Object, default: {} }
+      });
+      const userSchema = new Schema({
+        firstName: String,
+        props: { type: Object, default: {} }
+      }, { minimize: false });
+
+      const User = db.model('User', userSchema);
+      const Post = db.model('BlogPost', postSchema);
+
+      const user = new User({ firstName: 'test' });
+      const post = new Post({ owner: user });
+
+      let obj = post.toObject();
+      assert.strictEqual(obj.props, void 0);
+      assert.deepEqual(obj.owner.props, {});
+
+      obj = post.toObject({ minimize: false });
+      assert.deepEqual(obj.props, {});
+      assert.deepEqual(obj.owner.props, {});
+
+      obj = post.toObject({ minimize: true });
+      assert.strictEqual(obj.props, void 0);
+      assert.strictEqual(obj.owner.props, void 0);
+    });
   });
 
   describe('toJSON', function() {

From b018d2d0bc1b733f14eb138cf90bfd6b51ab09cd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Sep 2020 15:01:14 -0400
Subject: [PATCH 1200/2348] fix(document): respect child schema `minimize` if
 `toObject()` is called without an explicit `minimize`

Fix #9405
---
 lib/document.js    | 3 ++-
 test/utils.test.js | 2 --
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 11217cecc75..2c114e8d5b2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3078,13 +3078,14 @@ Document.prototype.$toObject = function(options, json) {
 
   // If options do not exist or is not an object, set it to empty object
   options = utils.isPOJO(options) ? clone(options) : {};
+  options._calledWithOptions = options._calledWithOptions || clone(options);
 
   if (!('flattenMaps' in options)) {
     options.flattenMaps = defaultOptions.flattenMaps;
   }
 
   let _minimize;
-  if (options.minimize != null) {
+  if (options._calledWithOptions.minimize != null) {
     _minimize = options.minimize;
   } else if (defaultOptions.minimize != null) {
     _minimize = defaultOptions.minimize;
diff --git a/test/utils.test.js b/test/utils.test.js
index bd4ce2c9073..dd9059c8d29 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -250,8 +250,6 @@ describe('utils', function() {
       assert.deepEqual(out.arr[0], { a: 42 });
       assert.deepEqual(out.arr[1], {});
       assert.deepEqual(out.arr[2], {});
-
-      return Promise.resolve();
     });
   });
 

From 915903d19441d00dccc02102f3b91753e615c829 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Sep 2020 15:25:28 -0400
Subject: [PATCH 1201/2348] docs: clean up incorrect arrow functions

---
 docs/guide.pug | 30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 45d4214a7f2..28096cf62da 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -170,9 +170,9 @@ block content
       const animalSchema = new Schema({ name: String, type: String });
 
       // assign a function to the "methods" object of our animalSchema
-      animalSchema.methods.findSimilarTypes = cb => (
-        mongoose.model('Animal').find({ type: this.type }, cb)
-      )
+      animalSchema.methods.findSimilarTypes = function(cb) {
+        return mongoose.model('Animal').find({ type: this.type }, cb);
+      };
     ```
 
     Now all of our `animal` instances have a `findSimilarTypes` method available
@@ -201,11 +201,11 @@ block content
 
     ```javascript
       // Assign a function to the "statics" object of our animalSchema
-      animalSchema.statics.findByName = name => (
-        this.find({ name: new RegExp(name, 'i') });
-       )
+      animalSchema.statics.findByName = function(name) {
+        return this.find({ name: new RegExp(name, 'i') });
+      };
       // Or, equivalently, you can call `animalSchema.static()`.
-      animalSchema.static('findByBreed', breed => this.find({ breed }) )
+      animalSchema.static('findByBreed', function(breed) { return this.find({ breed }); });
 
       const Animal = mongoose.model('Animal', animalSchema);
       let animals = await Animal.findByName('fido');
@@ -221,9 +221,9 @@ block content
     [chainable query builder API](./queries.html).
 
     ```javascript
-      animalSchema.query.byName = name => (
-        this.where({ name: new RegExp(name, 'i') })
-      )
+      animalSchema.query.byName = function(name) {
+        return this.where({ name: new RegExp(name, 'i') })
+      };
 
       const Animal = mongoose.model('Animal', animalSchema);
 
@@ -323,7 +323,7 @@ block content
     define a `fullName` property that won't get persisted to MongoDB.
 
     ```javascript
-    personSchema.virtual('fullName').get(() => {
+    personSchema.virtual('fullName').get(function() {
       return this.name.first + ' ' + this.name.last;
     });
     ```
@@ -346,8 +346,10 @@ block content
 
     ```javascript
     personSchema.virtual('fullName').
-      get(() => this.name.first + ' ' + this.name.last).
-      set(v => {
+      get(function() {
+        return this.name.first + ' ' + this.name.last;
+       }).
+      set(function(v) {
         this.name.first = v.substr(0, v.indexOf(' '));
         this.name.last = v.substr(v.indexOf(' ') + 1);
       });
@@ -813,7 +815,7 @@ block content
 
     ```javascript
     const schema = new Schema({ name: String });
-    schema.path('name').get(v => {
+    schema.path('name').get(function(v) {
       return v + ' is my name';
     });
     schema.set('toObject', { getters: true });

From 6b04250f153ab789e1077a7121b0fcffca0f6fa8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Sep 2020 15:58:44 -0400
Subject: [PATCH 1202/2348] docs(query): add tutorials links to nav bar when
 looking at queries guide

FIx #9410
---
 docs/css/mongoose5.css | 8 +++++++-
 docs/layout.pug        | 7 +++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/docs/css/mongoose5.css b/docs/css/mongoose5.css
index 3a20d714d83..2ca3b499b69 100644
--- a/docs/css/mongoose5.css
+++ b/docs/css/mongoose5.css
@@ -89,7 +89,13 @@ pre code {
 li.sub-item {
   height: 23px;
   font-size: 11pt;
-  margin-left: 20px;
+  margin-left: 15px;
+}
+
+li.tertiary-item {
+  height: 23px;
+  font-size: 11pt;
+  margin-left: 30px;
 }
 
 li.version {
diff --git a/docs/layout.pug b/docs/layout.pug
index 0a6293e7271..4efd04f7c6d 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -77,6 +77,13 @@ html(lang='en')
                 a.pure-menu-link(href="/docs/subdocs.html", class=outputUrl === '/docs/subdocs.html' ? 'selected' : '') Subdocuments
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/queries.html", class=outputUrl === '/docs/queries.html' ? 'selected' : '') Queries
+              - if (['/docs/queries', '/docs/tutorials/findoneandupdate', '/docs/tutorials/lean', '/docs/tutorials/query_casting'].some(path => outputUrl.startsWith(path)))
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/tutorials/query_casting.html", class=outputUrl === '/docs/tutorials/query_casting.html' ? 'selected' : '') Query Casting
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/tutorials/findoneandupdate.html", class=outputUrl === '/docs/tutorials/findoneandupdate.html' ? 'selected' : '') findOneAndUpdate
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/tutorials/lean.html", class=outputUrl === '/docs/tutorials/lean.html' ? 'selected' : '') The Lean Option
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/validation.html", class=outputUrl === '/docs/validation.html' ? 'selected' : '') Validation
               li.pure-menu-item.sub-item

From 7c512e029e493baf6d7476ae38c2f9034aa3ed9f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 11 Sep 2020 02:01:11 +0200
Subject: [PATCH 1203/2348] fix: bump mongodb driver to v3.6.2

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index dcbdb75203e..e6defe6ea60 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.6.1",
+    "mongodb": "3.6.2",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From d003ae36c1f80679eaaf9de87630c3de5332cbdb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Sep 2020 13:28:29 -0400
Subject: [PATCH 1204/2348] chore: release 5.10.5

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 63ffaf1cd2e..ef2058858dc 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.10.5 / 2020-09-11
+===================
+ * fix: bump mongodb -> 3.6.2 #9411 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(query+aggregate+cursor): support async iteration over a cursor instance as opposed to a Query or Aggregate instance #9403
+ * fix(document): respect child schema `minimize` if `toObject()` is called without an explicit `minimize` #9405
+ * docs(guide): use const instead of var #9394 [nainardev](https://github.com/nainardev)
+ * docs(query): link to lean, findOneAndUpdate, query casting tutorials from query docs #9410
+
 5.10.4 / 2020-09-09
 ===================
  * fix(document): allow setting nested path to instance of model #9392
diff --git a/package.json b/package.json
index e6defe6ea60..8dcb335d3d6 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.4",
+  "version": "5.10.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 33b43e92624937cc6cfb4d14159522519f6cae42 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Sep 2020 13:54:35 -0400
Subject: [PATCH 1205/2348] test: skip discriminators when cleaning test data
 to avoid error from #9412

---
 test/util.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/test/util.js b/test/util.js
index 99d480b90b5..4621b279d28 100644
--- a/test/util.js
+++ b/test/util.js
@@ -8,6 +8,11 @@ exports.clearTestData = function clearTestData(db) {
   const arr = [];
 
   for (const model of Object.keys(db.models)) {
+    const Model = db.models[model];
+    if (Model.baseModelName != null) {
+      // Skip discriminators
+      continue;
+    }
     arr.push(db.models[model].deleteMany({}));
     arr.push(db.models[model].collection.dropIndexes().catch(() => {}));
   }

From 34dcec625e2eb9f0a32942b8fe9498e07d769d5e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Sep 2020 12:58:57 -0400
Subject: [PATCH 1206/2348] fix(document): invalidate path if default function
 throws an error

Re: #9408
---
 lib/document.js | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 2c114e8d5b2..d617630fc86 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -397,21 +397,39 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
               continue;
             }
 
-            def = type.getDefault(doc, false);
+            try {
+              def = type.getDefault(doc, false);
+            } catch (err) {
+              doc.invalidate(p, err);
+              break;
+            }
+
             if (typeof def !== 'undefined') {
               doc_[piece] = def;
               doc.$__.activePaths.default(p);
             }
           } else if (included) {
             // selected field
-            def = type.getDefault(doc, false);
+            try {
+              def = type.getDefault(doc, false);
+            } catch (err) {
+              doc.invalidate(p, err);
+              break;
+            }
+
             if (typeof def !== 'undefined') {
               doc_[piece] = def;
               doc.$__.activePaths.default(p);
             }
           }
         } else {
-          def = type.getDefault(doc, false);
+          try {
+            def = type.getDefault(doc, false);
+          } catch (err) {
+            doc.invalidate(p, err);
+            break;
+          }
+
           if (typeof def !== 'undefined') {
             doc_[piece] = def;
             doc.$__.activePaths.default(p);

From b6afc5868b897e34a2e24da66f46d3797e8604ff Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Sep 2020 13:37:53 -0400
Subject: [PATCH 1207/2348] fix: ensure subdocument defaults run after initial
 values are set when initing

Fix #9408
---
 lib/schema/documentarray.js |  3 ++-
 test/document.test.js       | 41 +++++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 066d13f1593..ac88560286e 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -397,6 +397,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
   }
 
   const len = value.length;
+  const initDocumentOptions = { skipId: true, willInit: true };
 
   for (let i = 0; i < len; ++i) {
     if (!value[i]) {
@@ -429,7 +430,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
           selected = true;
         }
 
-        subdoc = new Constructor(null, value, true, selected, i);
+        subdoc = new Constructor(null, value, initDocumentOptions, selected, i);
         value[i] = subdoc.init(value[i]);
       } else {
         if (prev && typeof prev.id === 'function') {
diff --git a/test/document.test.js b/test/document.test.js
index 0b7af49daee..bd99c7902bd 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9354,4 +9354,45 @@ describe('document', function() {
 
     assert.equal(p.nested.test, 'new');
   });
+
+  it('marks path as errored if default function throws (gh-9408)', function() {
+    const jobSchema = new Schema({
+      deliveryAt: Date,
+      subJob: [{
+        deliveryAt: Date,
+        shippingAt: {
+          type: Date,
+          default: () => { throw new Error('Oops!'); }
+        },
+        prop: { type: String, default: 'default' }
+      }]
+    });
+
+    const Job = db.model('Test', jobSchema);
+
+    const doc = new Job({ subJob: [{ deliveryAt: new Date() }] });
+    assert.equal(doc.subJob[0].prop, 'default');
+  });
+
+  it('passes subdoc with initial values set to default function when init-ing (gh-9408)', function() {
+    const jobSchema = new Schema({
+      deliveryAt: Date,
+      subJob: [{
+        deliveryAt: Date,
+        shippingAt: {
+          type: Date,
+          default: function() {
+            return this.deliveryAt;
+          }
+        }
+      }]
+    });
+
+    const Job = db.model('Test', jobSchema);
+
+    const date = new Date();
+    const doc = new Job({ subJob: [{ deliveryAt: date }] });
+
+    assert.equal(doc.subJob[0].shippingAt.valueOf(), date.valueOf());
+  });
 });

From fd7397a605886bb2b47dd3f3fb6590060eda9f7e Mon Sep 17 00:00:00 2001
From: Madan Kumar <kumarmadan.j@gmail.com>
Date: Sat, 12 Sep 2020 20:17:10 +0530
Subject: [PATCH 1208/2348] Replace var with const in docs and test files

---
 docs/connections.pug              |   4 +-
 docs/faq.pug                      |  24 +++---
 docs/guide.pug                    |   8 +-
 docs/index.pug                    |   2 +-
 docs/middleware.pug               |   8 +-
 docs/models.pug                   |  12 +--
 docs/populate.pug                 |   2 +-
 docs/queries.pug                  |   4 +-
 docs/schematypes.pug              |  34 ++++-----
 docs/subdocs.pug                  |  28 +++----
 lib/aggregate.js                  |   8 +-
 lib/browser.js                    |  14 ++--
 lib/connection.js                 |  14 ++--
 lib/cursor/AggregationCursor.js   |   2 +-
 lib/cursor/QueryCursor.js         |   2 +-
 lib/error/messages.js             |   2 +-
 lib/index.js                      |  42 +++++------
 lib/model.js                      |  58 +++++++--------
 lib/query.js                      |  50 ++++++-------
 lib/schema.js                     |  30 ++++----
 lib/schema/buffer.js              |   6 +-
 lib/schema/date.js                |  30 ++++----
 lib/schema/number.js              |  34 ++++-----
 lib/schema/string.js              |  80 ++++++++++----------
 lib/schematype.js                 |  90 +++++++++++------------
 lib/types/buffer.js               |   4 +-
 lib/types/core_array.js           |  12 +--
 lib/types/decimal128.js           |   2 +-
 lib/types/documentarray.js        |   2 +-
 lib/types/embedded.js             |   2 +-
 lib/types/objectid.js             |   2 +-
 lib/virtualtype.js                |   4 +-
 test/docs/defaults.test.js        |  28 +++----
 test/docs/discriminators.test.js  | 118 +++++++++++++++---------------
 test/docs/promises.test.js        |  22 +++---
 test/docs/schemas.test.js         |  10 +--
 test/docs/schematypes.test.js     |  16 ++--
 test/docs/validation.test.js      | 104 +++++++++++++-------------
 test/es-next/promises.test.es6.js |  22 +++---
 tools/auth.js                     |   2 +-
 tools/repl.js                     |   4 +-
 tools/sharded.js                  |   4 +-
 42 files changed, 473 insertions(+), 473 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 3767b62f7ea..933c8f1812f 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -63,7 +63,7 @@ block content
 
     ```javascript
     mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
-    var MyModel = mongoose.model('Test', new Schema({ name: String }));
+    const MyModel = mongoose.model('Test', new Schema({ name: String }));
     // Works
     MyModel.findOne(function(error, result) { /* ... */ });
     ```
@@ -74,7 +74,7 @@ block content
     connecting.
 
     ```javascript
-    var MyModel = mongoose.model('Test', new Schema({ name: String }));
+    const MyModel = mongoose.model('Test', new Schema({ name: String }));
     // Will just hang until mongoose successfully connects
     MyModel.findOne(function(error, result) { /* ... */ });
 
diff --git a/docs/faq.pug b/docs/faq.pug
index 49f0090171b..256de1a488a 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -88,10 +88,10 @@ block content
     For example, if MongoDB doesn't already have a unique index on `name`, the below code will not error despite the fact that `unique` is true.
 
     ```javascript
-    var schema = new mongoose.Schema({
+    const schema = new mongoose.Schema({
       name: { type: String, unique: true }
     });
-    var Model = db.model('Test', schema);
+    const Model = db.model('Test', schema);
 
     Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
       console.log(err); // No error, unless index was already built
@@ -101,10 +101,10 @@ block content
     However, if you wait for the index to build using the `Model.on('index')` event, attempts to save duplicates will correctly error.
 
     ```javascript
-    var schema = new mongoose.Schema({
+    const schema = new mongoose.Schema({
       name: { type: String, unique: true }
     });
-    var Model = db.model('Test', schema);
+    const Model = db.model('Test', schema);
 
     Model.on('index', function(err) { // <-- Wait for model's indexes to finish
       assert.ifError(err);
@@ -135,12 +135,12 @@ block content
     <a href="#nested-properties">**Q**</a>. When I have a nested property in a schema, mongoose adds empty objects by default. Why?
 
     ```javascript
-    var schema = new mongoose.Schema({
+    const schema = new mongoose.Schema({
       nested: {
         prop: String
       }
     });
-    var Model = db.model('Test', schema);
+    const Model = db.model('Test', schema);
 
     // The below prints `{ _id: /* ... */, nested: {} }`, mongoose assigns
     // `nested` to an empty object `{}` by default.
@@ -198,7 +198,7 @@ block content
     // Do **NOT** use arrow functions as shown below unless you're certain
     // that's what you want. If you're reading this FAQ, odds are you should
     // just be using a conventional function.
-    var schema = new mongoose.Schema({
+    const schema = new mongoose.Schema({
       propWithGetter: {
         type: String,
         get: v => {
@@ -320,7 +320,7 @@ block content
     mongoose.connection.on('error', handleError);
 
     // if connecting on a separate connection
-    var conn = mongoose.createConnection(..);
+    const conn = mongoose.createConnection(..);
     conn.on('error', handleError);
     ```
 
@@ -355,14 +355,14 @@ block content
     same name, create a new connection and bind the model to the connection.
 
     ```javascript
-    var mongoose = require('mongoose');
-    var connection = mongoose.createConnection(..);
+    const mongoose = require('mongoose');
+    const connection = mongoose.createConnection(..);
 
     // use mongoose.Schema
-    var kittySchema = mongoose.Schema({ name: String });
+    const kittySchema = mongoose.Schema({ name: String });
 
     // use connection.model
-    var Kitten = connection.model('Kitten', kittySchema);
+    const Kitten = connection.model('Kitten', kittySchema);
     ```
 
 
diff --git a/docs/guide.pug b/docs/guide.pug
index 28096cf62da..803d214dce4 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -179,7 +179,7 @@ block content
     to them.
 
     ```javascript
-      var Animal = mongoose.model('Animal', animalSchema);
+      const Animal = mongoose.model('Animal', animalSchema);
       const dog = new Animal({ type: 'dog' });
 
       dog.findSimilarTypes((err, dogs) => {
@@ -492,7 +492,7 @@ block content
     to false.
 
     ```javascript
-    var schema = new Schema({..}, { bufferCommands: false });
+    const schema = new Schema({..}, { bufferCommands: false });
     ```
 
     The schema `bufferCommands` option overrides the global `bufferCommands` option.
@@ -550,7 +550,7 @@ block content
 
     // disabled id
     const schema = new Schema({ name: String }, { id: false });
-    var Page = mongoose.model('Page', schema);
+    const Page = mongoose.model('Page', schema);
     const p = new Page({ name: 'mongodb.org' });
     console.log(p.id); // undefined
     ```
@@ -1135,7 +1135,7 @@ block content
 
     ```javascript
     const childSchema = new Schema({}, { strict: false });
-    var parentSchema = new Schema({ child: childSchema },
+    const parentSchema = new Schema({ child: childSchema },
       { strict: 'throw', useNestedStrict: true });
     const Parent = mongoose.model('Parent', parentSchema);
     Parent.update({}, { 'child.name': 'Luke Skywalker' }, error => {
diff --git a/docs/index.pug b/docs/index.pug
index d600fecf6ba..133926c9503 100644
--- a/docs/index.pug
+++ b/docs/index.pug
@@ -21,7 +21,7 @@ block content
     Next install Mongoose from the command line using `npm`:
 
     ```
-    $ npm install mongoose
+    $ npm install mongoose --save
     ```
 
     Now say we like fuzzy kittens and want to record every kitten we ever meet
diff --git a/docs/middleware.pug b/docs/middleware.pug
index 3c09f637828..417175efeb2 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -105,7 +105,7 @@ block content
     middleware calls `next`.
 
     ```javascript
-    var schema = new Schema(..);
+    const schema = new Schema(..);
     schema.pre('save', function(next) {
       // do stuff
       next();
@@ -133,7 +133,7 @@ block content
     to prevent the rest of your middleware function from running when you call `next()`.
 
     ```javascript
-    var schema = new Schema(..);
+    const schema = new Schema(..);
     schema.pre('save', function(next) {
       if (foo()) {
         console.log('calling next!');
@@ -426,7 +426,7 @@ block content
     Error handling middleware can then transform the error however you want.
 
     ```javascript
-    var schema = new Schema({
+    const schema = new Schema({
       name: {
         type: String,
         // Will trigger a MongoError with code 11000 when
@@ -466,7 +466,7 @@ block content
       }
     });
 
-    var people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
+    const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
     Person.create(people, function(error) {
       Person.update({ name: 'Slash' }, { $set: { name: 'Axl Rose' } }, function(error) {
         // `error.message` will be "There was a duplicate key error"
diff --git a/docs/models.pug b/docs/models.pug
index a97d379ce63..7c4b27ff2e0 100644
--- a/docs/models.pug
+++ b/docs/models.pug
@@ -47,8 +47,8 @@ block content
     for you.
 
     ```javascript
-    var schema = new mongoose.Schema({ name: 'string', size: 'string' });
-    var Tank = mongoose.model('Tank', schema);
+    const schema = new mongoose.Schema({ name: 'string', size: 'string' });
+    const Tank = mongoose.model('Tank', schema);
     ```
   :markdown
     The first argument is the _singular_ name of the collection your model is
@@ -66,9 +66,9 @@ block content
     them and saving to the database is easy.
 
     ```javascript
-    var Tank = mongoose.model('Tank', yourSchema);
+    const Tank = mongoose.model('Tank', yourSchema);
 
-    var small = new Tank({ size: 'small' });
+    const small = new Tank({ size: 'small' });
     small.save(function (err) {
       if (err) return handleError(err);
       // saved!
@@ -97,8 +97,8 @@ block content
     If you create a custom connection, use that connection's `model()` function
     instead.
     ```javascript
-    var connection = mongoose.createConnection('mongodb://localhost:27017/test');
-    var Tank = connection.model('Tank', yourSchema);
+    const connection = mongoose.createConnection('mongodb://localhost:27017/test');
+    const Tank = connection.model('Tank', yourSchema);
     ```
   h3(id="querying") Querying
   :markdown
diff --git a/docs/populate.pug b/docs/populate.pug
index a55f35dbeb2..2ad6b0c54eb 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -430,7 +430,7 @@ block content
     Say you have a user schema which keeps track of the user's friends.
 
     ```javascript
-    var userSchema = new Schema({
+    const userSchema = new Schema({
       name: String,
       friends: [{ type: ObjectId, ref: 'User' }]
     });
diff --git a/docs/queries.pug b/docs/queries.pug
index 85f94f4b56b..4a79b3a097f 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -62,7 +62,7 @@ block content
     When executing a query with a `callback` function, you specify your query as a JSON document. The JSON document's syntax is the same as the [MongoDB shell](http://docs.mongodb.org/manual/tutorial/query-documents/).
 
     ```javascript
-    var Person = mongoose.model('Person', yourSchema);
+    const Person = mongoose.model('Person', yourSchema);
 
     // find each person with a last name matching 'Ghost', selecting the `name` and `occupation` fields
     Person.findOne({ 'name.last': 'Ghost' }, 'name occupation', function (err, person) {
@@ -83,7 +83,7 @@ block content
 
     ```javascript
     // find each person with a last name matching 'Ghost'
-    var query = Person.findOne({ 'name.last': 'Ghost' });
+    const query = Person.findOne({ 'name.last': 'Ghost' });
 
     // selecting the `name` and `occupation` fields
     query.select('name occupation');
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index daeccc90405..2309045890d 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -86,7 +86,7 @@ block content
     <h4>Example</h4>
 
     ```javascript
-    var schema = new Schema({
+    const schema = new Schema({
       name:    String,
       binary:  Buffer,
       living:  Boolean,
@@ -117,9 +117,9 @@ block content
 
     // example use
 
-    var Thing = mongoose.model('Thing', schema);
+    const Thing = mongoose.model('Thing', schema);
 
-    var m = new Thing;
+    const m = new Thing;
     m.name = 'Statue of Liberty';
     m.age = 125;
     m.updated = new Date;
@@ -196,11 +196,11 @@ block content
     a `type` property.
 
     ```javascript
-    var schema1 = new Schema({
+    const schema1 = new Schema({
       test: String // `test` is a path of type String
     });
 
-    var schema2 = new Schema({
+    const schema2 = new Schema({
       // The `test` object contains the "SchemaType options"
       test: { type: String } // `test` is a path of type string
     });
@@ -210,7 +210,7 @@ block content
     for a path. For example, if you want to lowercase a string before saving:
 
     ```javascript
-    var schema2 = new Schema({
+    const schema2 = new Schema({
       test: {
         type: String,
         lowercase: true // Always convert `test` to lowercase
@@ -271,7 +271,7 @@ block content
     * `sparse`: boolean, whether to define a [sparse index](https://docs.mongodb.com/manual/core/index-sparse/) on this property.
 
     ```javascript
-    var schema2 = new Schema({
+    const schema2 = new Schema({
       test: {
         type: String,
         index: true,
@@ -362,7 +362,7 @@ block content
     [Built-in `Date` methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date) are [__not__ hooked into](https://github.com/Automattic/mongoose/issues/1598) the mongoose change tracking logic which in English means that if you use a `Date` in your document and modify it with a method like `setMonth()`, mongoose will be unaware of this change and `doc.save()` will not persist this modification. If you must modify `Date` types using built-in methods, tell mongoose about the change with `doc.markModified('pathToYourDate')` before saving.
 
     ```javascript
-    var Assignment = mongoose.model('Assignment', { dueDate: Date });
+    const Assignment = mongoose.model('Assignment', { dueDate: Date });
     Assignment.findOne(function (err, doc) {
       doc.dueDate.setMonth(3);
       doc.save(callback); // THIS DOES NOT SAVE YOUR CHANGE
@@ -502,8 +502,8 @@ block content
     _document arrays_.
 
     ```javascript
-    var ToySchema = new Schema({ name: String });
-    var ToyBoxSchema = new Schema({
+    const ToySchema = new Schema({ name: String });
+    const ToyBoxSchema = new Schema({
       toys: [ToySchema],
       buffers: [Buffer],
       strings: [String],
@@ -515,14 +515,14 @@ block content
     Arrays are special because they implicitly have a default value of `[]` (empty array).
 
     ```javascript
-    var ToyBox = mongoose.model('ToyBox', ToyBoxSchema);
+    const ToyBox = mongoose.model('ToyBox', ToyBoxSchema);
     console.log((new ToyBox()).toys); // []
     ```
 
     To overwrite this default, you need to set the default value to `undefined`
 
     ```javascript
-    var ToyBoxSchema = new Schema({
+    const ToyBoxSchema = new Schema({
       toys: {
         type: [ToySchema],
         default: undefined
@@ -534,10 +534,10 @@ block content
     `Mixed`:
 
     ```javascript
-    var Empty1 = new Schema({ any: [] });
-    var Empty2 = new Schema({ any: Array });
-    var Empty3 = new Schema({ any: [Schema.Types.Mixed] });
-    var Empty4 = new Schema({ any: [{}] });
+    const Empty1 = new Schema({ any: [] });
+    const Empty2 = new Schema({ any: Array });
+    const Empty3 = new Schema({ any: [Schema.Types.Mixed] });
+    const Empty4 = new Schema({ any: [{}] });
     ```
 
     <h4 id="maps">Maps</h4>
@@ -705,7 +705,7 @@ block content
     given path.
 
     ```javascript
-    var sampleSchema = new Schema({ name: { type: String, required: true } });
+    const sampleSchema = new Schema({ name: { type: String, required: true } });
     console.log(sampleSchema.path('name'));
     // Output looks like:
     /**
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index 86a5bb9de88..75400f2b6c3 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -27,9 +27,9 @@ block content
     distinct notions of subdocuments: [arrays of subdocuments](https://masteringjs.io/tutorials/mongoose/array#document-arrays) and single nested
     subdocuments.
     ```javascript
-    var childSchema = new Schema({ name: 'string' });
+    const childSchema = new Schema({ name: 'string' });
 
-    var parentSchema = new Schema({
+    const parentSchema = new Schema({
       // Array of subdocuments
       children: [childSchema],
       // Single nested subdocuments. Caveat: single nested subdocs only work
@@ -62,8 +62,8 @@ block content
     not saved individually, they are saved whenever their top-level parent
     document is saved.
     ```javascript
-    var Parent = mongoose.model('Parent', parentSchema);
-    var parent = new Parent({ children: [{ name: 'Matt' }, { name: 'Sarah' }] })
+    const Parent = mongoose.model('Parent', parentSchema);
+    const parent = new Parent({ children: [{ name: 'Matt' }, { name: 'Sarah' }] })
     parent.children[0].name = 'Matthew';
 
     // `parent.children[0].save()` is a no-op, it triggers middleware but
@@ -85,7 +85,7 @@ block content
       next();
     });
 
-    var parent = new Parent({ children: [{ name: 'invalid' }] });
+    const parent = new Parent({ children: [{ name: 'invalid' }] });
     parent.save(function (err) {
       console.log(err.message) // #sadpanda
     });
@@ -98,7 +98,7 @@ block content
 
     ```javascript
     // Below code will print out 1-4 in order
-    var childSchema = new mongoose.Schema({ name: 'string' });
+    const childSchema = new mongoose.Schema({ name: 'string' });
 
     childSchema.pre('validate', function(next) {
       console.log('2');
@@ -110,7 +110,7 @@ block content
       next();
     });
 
-    var parentSchema = new mongoose.Schema({
+    const parentSchema = new mongoose.Schema({
       child: childSchema
     });
 
@@ -184,7 +184,7 @@ block content
     special [id](./api.html#types_documentarray_MongooseDocumentArray-id) method
     for searching a document array to find a document with a given `_id`.
     ```javascript
-    var doc = parent.children.id(_id);
+    const doc = parent.children.id(_id);
     ```
   h3#adding-subdocs-to-arrays Adding Subdocs to Arrays
   :markdown
@@ -194,12 +194,12 @@ block content
     [addToSet](./api.html#mongoosearray_MongooseArray-addToSet),
     and others cast arguments to their proper types transparently:
     ```javascript
-    var Parent = mongoose.model('Parent');
-    var parent = new Parent;
+    const Parent = mongoose.model('Parent');
+    const parent = new Parent;
 
     // create a comment
     parent.children.push({ name: 'Liesl' });
-    var subdoc = parent.children[0];
+    const subdoc = parent.children[0];
     console.log(subdoc) // { _id: '501d86090d371bab2c0341c5', name: 'Liesl' }
     subdoc.isNew; // true
 
@@ -213,7 +213,7 @@ block content
     [create](./api.html#types_documentarray_MongooseDocumentArray.create)
     method of MongooseArrays.
     ```javascript
-    var newdoc = parent.children.create({ name: 'Aaron' });
+    const newdoc = parent.children.create({ name: 'Aaron' });
     ```
   h3#removing-subdocs Removing Subdocs
   :markdown
@@ -280,11 +280,11 @@ block content
     convert the object to a schema for you:
 
     ```javascript
-    var parentSchema = new Schema({
+    const parentSchema = new Schema({
       children: [{ name: 'string' }]
     });
     // Equivalent
-    var parentSchema = new Schema({
+    const parentSchema = new Schema({
       children: [new Schema({ name: 'string' })]
     });
     ```
diff --git a/lib/aggregate.js b/lib/aggregate.js
index ed15c584dfb..6dc43926f86 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -125,7 +125,7 @@ Aggregate.prototype.model = function(model) {
  *     aggregate.append({ $project: { field: 1 }}, { $limit: 2 });
  *
  *     // or pass an array
- *     var pipeline = [{ $match: { daw: 'Logic Audio X' }} ];
+ *     const pipeline = [{ $match: { daw: 'Logic Audio X' }} ];
  *     aggregate.append(pipeline);
  *
  * @param {Object} ops operator(s) to append
@@ -793,7 +793,7 @@ Aggregate.prototype.session = function(session) {
  *
  * ####Example:
  *
- *     var agg = Model.aggregate(..).option({ allowDiskUse: true }); // Set the `allowDiskUse` option
+ *     const agg = Model.aggregate(..).option({ allowDiskUse: true }); // Set the `allowDiskUse` option
  *     agg.options; // `{ allowDiskUse: true }`
  *
  * @param {Object} options keys to merge into current options
@@ -820,7 +820,7 @@ Aggregate.prototype.option = function(value) {
  *
  * ####Example:
  *
- *     var cursor = Model.aggregate(..).cursor({ batchSize: 1000 }).exec();
+ *     const cursor = Model.aggregate(..).cursor({ batchSize: 1000 }).exec();
  *     cursor.eachAsync(function(doc, i) {
  *       // use doc
  *     });
@@ -960,7 +960,7 @@ Aggregate.prototype.pipeline = function() {
  *     aggregate.exec(callback);
  *
  *     // Because a promise is returned, the `callback` is optional.
- *     var promise = aggregate.exec();
+ *     const promise = aggregate.exec();
  *     promise.then(..);
  *
  * @see Promise #promise_Promise
diff --git a/lib/browser.js b/lib/browser.js
index b151d51b674..f716f2aee71 100644
--- a/lib/browser.js
+++ b/lib/browser.js
@@ -48,9 +48,9 @@ exports.Error = require('./error/index');
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
- *     var Schema = mongoose.Schema;
- *     var CatSchema = new Schema(..);
+ *     const mongoose = require('mongoose');
+ *     const Schema = mongoose.Schema;
+ *     const CatSchema = new Schema(..);
  *
  * @method Schema
  * @api public
@@ -63,8 +63,8 @@ exports.Schema = require('./schema');
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
- *     var array = mongoose.Types.Array;
+ *     const mongoose = require('mongoose');
+ *     const array = mongoose.Types.Array;
  *
  * ####Types:
  *
@@ -76,8 +76,8 @@ exports.Schema = require('./schema');
  *
  * Using this exposed access to the `ObjectId` type, we can construct ids on demand.
  *
- *     var ObjectId = mongoose.Types.ObjectId;
- *     var id1 = new ObjectId;
+ *     const ObjectId = mongoose.Types.ObjectId;
+ *     const id1 = new ObjectId;
  *
  * @property Types
  * @api public
diff --git a/lib/connection.js b/lib/connection.js
index 106103ce01e..dcf616e6e3a 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1091,17 +1091,17 @@ Connection.prototype.plugin = function(fn, opts) {
 /**
  * Defines or retrieves a model.
  *
- *     var mongoose = require('mongoose');
- *     var db = mongoose.createConnection(..);
+ *     const mongoose = require('mongoose');
+ *     const db = mongoose.createConnection(..);
  *     db.model('Venue', new Schema(..));
- *     var Ticket = db.model('Ticket', new Schema(..));
- *     var Venue = db.model('Venue');
+ *     const Ticket = db.model('Ticket', new Schema(..));
+ *     const Venue = db.model('Venue');
  *
  * _When no `collection` argument is passed, Mongoose produces a collection name by passing the model `name` to the [utils.toCollectionName](#utils_exports.toCollectionName) method. This method pluralizes the name. If you don't like this behavior, either pass a collection name or set your schemas collection name option._
  *
  * ####Example:
  *
- *     var schema = new Schema({ name: String }, { collection: 'actor' });
+ *     const schema = new Schema({ name: String }, { collection: 'actor' });
  *
  *     // or
  *
@@ -1109,8 +1109,8 @@ Connection.prototype.plugin = function(fn, opts) {
  *
  *     // or
  *
- *     var collectionName = 'actor'
- *     var M = conn.model('Actor', schema, collectionName)
+ *     const collectionName = 'actor'
+ *     const M = conn.model('Actor', schema, collectionName)
  *
  * @param {String|Function} name the model name or class extending Model
  * @param {Schema} [schema] a schema. necessary when defining a model
diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 71a13538f22..5023b1c7f8f 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -125,7 +125,7 @@ if (Symbol.asyncIterator != null) {
  *       on('data', function(doc) { console.log(doc.foo); });
  *
  *     // Or map documents returned by `.next()`
- *     var cursor = Thing.find({ name: /^hello/ }).
+ *     const cursor = Thing.find({ name: /^hello/ }).
  *       cursor().
  *       map(function (doc) {
  *         doc.foo = "bar";
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 656cd4a5bf2..2b5f2c164ba 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -118,7 +118,7 @@ QueryCursor.prototype._read = function() {
  *       on('data', function(doc) { console.log(doc.foo); });
  *
  *     // Or map documents returned by `.next()`
- *     var cursor = Thing.find({ name: /^hello/ }).
+ *     const cursor = Thing.find({ name: /^hello/ }).
  *       cursor().
  *       map(function (doc) {
  *         doc.foo = "bar";
diff --git a/lib/error/messages.js b/lib/error/messages.js
index 78fb6d5dc7e..ac0294a39a4 100644
--- a/lib/error/messages.js
+++ b/lib/error/messages.js
@@ -3,7 +3,7 @@
  * The default built-in validator error messages. These may be customized.
  *
  *     // customize within each schema or globally like so
- *     var mongoose = require('mongoose');
+ *     const mongoose = require('mongoose');
  *     mongoose.Error.messages.String.enum  = "Your custom message for {PATH}.";
  *
  * As you might have noticed, error messages support basic templating
diff --git a/lib/index.js b/lib/index.js
index 5ac7c9a949e..ce42cd8bc01 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -228,18 +228,18 @@ Mongoose.prototype.get = Mongoose.prototype.set;
  *     db = mongoose.createConnection('mongodb://user:pass@localhost:port/database');
  *
  *     // and options
- *     var opts = { db: { native_parser: true }}
+ *     const opts = { db: { native_parser: true }}
  *     db = mongoose.createConnection('mongodb://user:pass@localhost:port/database', opts);
  *
  *     // replica sets
  *     db = mongoose.createConnection('mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/database');
  *
  *     // and options
- *     var opts = { replset: { strategy: 'ping', rs_name: 'testSet' }}
+ *     const opts = { replset: { strategy: 'ping', rs_name: 'testSet' }}
  *     db = mongoose.createConnection('mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/database', opts);
  *
  *     // and options
- *     var opts = { server: { auto_reconnect: false }, user: 'username', pass: 'mypassword' }
+ *     const opts = { server: { auto_reconnect: false }, user: 'username', pass: 'mypassword' }
  *     db = mongoose.createConnection('localhost', 'database', port, opts)
  *
  *     // initialize now, connect later
@@ -294,14 +294,14 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  *     mongoose.connect('mongodb://user:pass@localhost:port/database');
  *
  *     // replica sets
- *     var uri = 'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/mydatabase';
+ *     const uri = 'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/mydatabase';
  *     mongoose.connect(uri);
  *
  *     // with options
  *     mongoose.connect(uri, options);
  *
  *     // optional callback that gets fired when initial connection completed
- *     var uri = 'mongodb://nonexistent.domain:27000';
+ *     const uri = 'mongodb://nonexistent.domain:27000';
  *     mongoose.connect(uri, function(error) {
  *       // if error is truthy, the initial connection failed.
  *     })
@@ -427,17 +427,17 @@ Mongoose.prototype.pluralize = function(fn) {
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
+ *     const mongoose = require('mongoose');
  *
  *     // define an Actor model with this mongoose instance
  *     const schema = new Schema({ name: String });
  *     mongoose.model('Actor', schema);
  *
  *     // create a new connection
- *     var conn = mongoose.createConnection(..);
+ *     const conn = mongoose.createConnection(..);
  *
  *     // create Actor model
- *     var Actor = conn.model('Actor', schema);
+ *     const Actor = conn.model('Actor', schema);
  *     conn.model('Actor') === Actor; // true
  *     conn.model('Actor', schema) === Actor; // true, same schema
  *     conn.model('Actor', schema, 'actors') === Actor; // true, same schema and collection name
@@ -449,7 +449,7 @@ Mongoose.prototype.pluralize = function(fn) {
  *
  * ####Example:
  *
- *     var schema = new Schema({ name: String }, { collection: 'actor' });
+ *     const schema = new Schema({ name: String }, { collection: 'actor' });
  *
  *     // or
  *
@@ -457,8 +457,8 @@ Mongoose.prototype.pluralize = function(fn) {
  *
  *     // or
  *
- *     var collectionName = 'actor'
- *     var M = mongoose.model('Actor', schema, collectionName)
+ *     const collectionName = 'actor'
+ *     const M = mongoose.model('Actor', schema, collectionName)
  *
  * @param {String|Function} name model name or class extending Model
  * @param {Schema} [schema] the schema to use.
@@ -673,7 +673,7 @@ Mongoose.prototype.plugin = function(fn, opts) {
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
+ *     const mongoose = require('mongoose');
  *     mongoose.connect(...);
  *     mongoose.connection.on('error', cb);
  *
@@ -788,8 +788,8 @@ Mongoose.prototype.version = pkg.version;
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
- *     var mongoose2 = new mongoose.Mongoose();
+ *     const mongoose = require('mongoose');
+ *     const mongoose2 = new mongoose.Mongoose();
  *
  * @method Mongoose
  * @api public
@@ -802,9 +802,9 @@ Mongoose.prototype.Mongoose = Mongoose;
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
- *     var Schema = mongoose.Schema;
- *     var CatSchema = new Schema(..);
+ *     const mongoose = require('mongoose');
+ *     const Schema = mongoose.Schema;
+ *     const CatSchema = new Schema(..);
  *
  * @method Schema
  * @api public
@@ -849,8 +849,8 @@ Mongoose.prototype.VirtualType = VirtualType;
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
- *     var array = mongoose.Types.Array;
+ *     const mongoose = require('mongoose');
+ *     const array = mongoose.Types.Array;
  *
  * ####Types:
  *
@@ -862,8 +862,8 @@ Mongoose.prototype.VirtualType = VirtualType;
  *
  * Using this exposed access to the `ObjectId` type, we can construct ids on demand.
  *
- *     var ObjectId = mongoose.Types.ObjectId;
- *     var id1 = new ObjectId;
+ *     const ObjectId = mongoose.Types.ObjectId;
+ *     const id1 = new ObjectId;
  *
  * @property Types
  * @api public
diff --git a/lib/model.js b/lib/model.js
index 84b4220bd3d..8b4b8e08974 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1021,7 +1021,7 @@ Model.prototype.$__deleteOne = Model.prototype.$__remove;
  *
  * ####Example:
  *
- *     var doc = new Tank;
+ *     const doc = new Tank;
  *     doc.model('User').findById(id, callback);
  *
  * @param {String} name model name
@@ -1096,15 +1096,15 @@ Model.exists = function exists(filter, options, callback) {
  *     }
  *     util.inherits(BaseSchema, Schema);
  *
- *     var PersonSchema = new BaseSchema();
- *     var BossSchema = new BaseSchema({ department: String });
+ *     const PersonSchema = new BaseSchema();
+ *     const BossSchema = new BaseSchema({ department: String });
  *
- *     var Person = mongoose.model('Person', PersonSchema);
- *     var Boss = Person.discriminator('Boss', BossSchema);
+ *     const Person = mongoose.model('Person', PersonSchema);
+ *     const Boss = Person.discriminator('Boss', BossSchema);
  *     new Boss().__t; // "Boss". `__t` is the default `discriminatorKey`
  *
- *     var employeeSchema = new Schema({ boss: ObjectId });
- *     var Employee = Person.discriminator('Employee', employeeSchema, 'staff');
+ *     const employeeSchema = new Schema({ boss: ObjectId });
+ *     const Employee = Person.discriminator('Employee', employeeSchema, 'staff');
  *     new Employee().__t; // "staff" because of 3rd argument above
  *
  * @param {String} name discriminator model name
@@ -1204,10 +1204,10 @@ for (const i in EventEmitter.prototype) {
  *
  * ####Example:
  *
- *     var eventSchema = new Schema({ thing: { type: 'string', unique: true }})
+ *     const eventSchema = new Schema({ thing: { type: 'string', unique: true }})
  *     // This calls `Event.init()` implicitly, so you don't need to call
  *     // `Event.init()` on your own.
- *     var Event = mongoose.model('Event', eventSchema);
+ *     const Event = mongoose.model('Event', eventSchema);
  *
  *     Event.init().then(function(Event) {
  *       // You can also use `Event.on('index')` if you prefer event emitters
@@ -1291,8 +1291,8 @@ Model.init = function init(callback) {
  *
  * ####Example:
  *
- *     var userSchema = new Schema({ name: String })
- *     var User = mongoose.model('User', userSchema);
+ *     const userSchema = new Schema({ name: String })
+ *     const User = mongoose.model('User', userSchema);
  *
  *     User.createCollection().then(function(collection) {
  *       console.log('Collection is created!');
@@ -1505,8 +1505,8 @@ Model.listIndexes = function init(callback) {
  *
  * ####Example:
  *
- *     var eventSchema = new Schema({ thing: { type: 'string', unique: true }})
- *     var Event = mongoose.model('Event', eventSchema);
+ *     const eventSchema = new Schema({ thing: { type: 'string', unique: true }})
+ *     const Event = mongoose.model('Event', eventSchema);
  *
  *     Event.on('index', function (err) {
  *       if (err) console.error(err); // error occurred during index creation
@@ -2283,7 +2283,7 @@ Model.count = function count(conditions, callback) {
  *       console.log('unique urls with more than 100 clicks', result);
  *     })
  *
- *     var query = Link.distinct('url');
+ *     const query = Link.distinct('url');
  *     query.exec(callback);
  *
  * @param {String} field
@@ -2392,7 +2392,7 @@ Model.$where = function $where() {
  *
  * ####Example:
  *
- *     var query = { name: 'borne' };
+ *     const query = { name: 'borne' };
  *     Model.findOneAndUpdate(query, { name: 'jason bourne' }, options, callback)
  *
  *     // is sent as
@@ -3195,7 +3195,7 @@ Model.startSession = function() {
  *
  * ####Example:
  *
- *     var arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
+ *     const arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
  *     Movies.insertMany(arr, function(error, docs) {});
  *
  * @param {Array|Object|*} doc(s)
@@ -3494,7 +3494,7 @@ Model.bulkWrite = function(ops, options, callback) {
  * ####Example:
  *
  *     // hydrate previous data into a Mongoose document
- *     var mongooseCandy = Candy.hydrate({ _id: '54108337212ffb6d459f854c', type: 'jelly bean' });
+ *     const mongooseCandy = Candy.hydrate({ _id: '54108337212ffb6d459f854c', type: 'jelly bean' });
  *
  * @param {Object} obj
  * @param {Object|String} [projection] optional projection containing which fields should be selected for this document
@@ -3552,7 +3552,7 @@ Model.hydrate = function(obj, projection) {
  *
  * ####Example:
  *
- *     var query = { name: 'borne' };
+ *     const query = { name: 'borne' };
  *     Model.update(query, { name: 'jason bourne' }, options, callback);
  *
  *     // is sent as
@@ -3762,7 +3762,7 @@ function _update(model, op, conditions, doc, options, callback) {
  *
  * ####Example:
  *
- *     var o = {};
+ *     const o = {};
  *     // `map()` and `reduce()` are run on the MongoDB server, not Node.js,
  *     // these functions are converted to strings
  *     o.map = function () { emit(this.name, 1) };
@@ -3795,7 +3795,7 @@ function _update(model, op, conditions, doc, options, callback) {
  *
  * ####Example:
  *
- *     var o = {};
+ *     const o = {};
  *     // You can also define `map()` and `reduce()` as strings if your
  *     // linter complains about `emit()` not being defined
  *     o.map = 'function () { emit(this.name, 1) }';
@@ -3813,10 +3813,10 @@ function _update(model, op, conditions, doc, options, callback) {
  *     // `mapReduce()` returns a promise. However, ES6 promises can only
  *     // resolve to exactly one value,
  *     o.resolveToObject = true;
- *     var promise = User.mapReduce(o);
+ *     const promise = User.mapReduce(o);
  *     promise.then(function (res) {
- *       var model = res.model;
- *       var stats = res.stats;
+ *       const model = res.model;
+ *       const stats = res.stats;
  *       console.log('map reduce took %d ms', stats.processtime)
  *       return model.find().where('value').gt(10).exec();
  *     }).then(function (docs) {
@@ -4087,7 +4087,7 @@ Model.validate = function validate(obj, pathsToValidate, context, callback) {
  *
  * ####Example:
  *
- *     var options = { near: [10, 10], maxDistance: 5 };
+ *     const options = { near: [10, 10], maxDistance: 5 };
  *     Locations.geoSearch({ type : "house" }, options, function(err, res) {
  *       console.log(res);
  *     });
@@ -4183,7 +4183,7 @@ Model.geoSearch = function(conditions, options, callback) {
  *
  *     // populates a single object
  *     User.findById(id, function (err, user) {
- *       var opts = [
+ *       const opts = [
  *         { path: 'company', match: { x: 1 }, select: 'name' },
  *         { path: 'notes', options: { limit: 10 }, model: 'override' }
  *       ];
@@ -4195,9 +4195,9 @@ Model.geoSearch = function(conditions, options, callback) {
  *
  *     // populates an array of objects
  *     User.find(match, function (err, users) {
- *       var opts = [{ path: 'company', match: { x: 1 }, select: 'name' }];
+ *       const opts = [{ path: 'company', match: { x: 1 }, select: 'name' }];
  *
- *       var promise = User.populate(users, opts);
+ *       const promise = User.populate(users, opts);
  *       promise.then(console.log).end();
  *     })
  *
@@ -4210,13 +4210,13 @@ Model.geoSearch = function(conditions, options, callback) {
  *     //   weapon: { type: ObjectId, ref: 'Weapon' }
  *     // });
  *
- *     var user = { name: 'Indiana Jones', weapon: 389 };
+ *     const user = { name: 'Indiana Jones', weapon: 389 };
  *     Weapon.populate(user, { path: 'weapon', model: 'Weapon' }, function (err, user) {
  *       console.log(user.weapon.name); // whip
  *     })
  *
  *     // populate many plain objects
- *     var users = [{ name: 'Indiana Jones', weapon: 389 }]
+ *     const users = [{ name: 'Indiana Jones', weapon: 389 }]
  *     users.push({ name: 'Batman', weapon: 8921 })
  *     Weapon.populate(users, { path: 'weapon' }, function (err, users) {
  *       users.forEach(function (user) {
diff --git a/lib/query.js b/lib/query.js
index a2816f8e46b..38b91c7d7b8 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -141,10 +141,10 @@ Query.use$geoWithin = mquery.use$geoWithin;
  *     // Create a query for adventure movies and read from the primary
  *     // node in the replica-set unless it is down, in which case we'll
  *     // read from a secondary node.
- *     var query = Movie.find({ tags: 'adventure' }).read('primaryPreferred');
+ *     const query = Movie.find({ tags: 'adventure' }).read('primaryPreferred');
  *
  *     // create a custom Query constructor based off these settings
- *     var Adventure = query.toConstructor();
+ *     const Adventure = query.toConstructor();
  *
  *     // Adventure is now a subclass of mongoose.Query and works the same way but with the
  *     // default query parameters and options set.
@@ -1256,7 +1256,7 @@ Query.prototype.wtimeout = function wtimeout(ms) {
  *
  * ####Example:
  *
- *     var query = new Query();
+ *     const query = new Query();
  *     query.limit(10);
  *     query.setOptions({ maxTimeMS: 1000 })
  *     query.getOptions(); // { limit: 10, maxTimeMS: 1000 }
@@ -1447,7 +1447,7 @@ Query.prototype.getFilter = function() {
  *
  * ####Example:
  *
- *     var query = new Query();
+ *     const query = new Query();
  *     query.find({ a: 1 }).where('b').gt(2);
  *     query.getQuery(); // { a: 1, b: { $gt: 2 } }
  *
@@ -1464,7 +1464,7 @@ Query.prototype.getQuery = function() {
  *
  * ####Example:
  *
- *     var query = new Query();
+ *     const query = new Query();
  *     query.find({ a: 1 })
  *     query.setQuery({ a: 2 });
  *     query.getQuery(); // { a: 2 }
@@ -1483,7 +1483,7 @@ Query.prototype.setQuery = function(val) {
  *
  * ####Example:
  *
- *     var query = new Query();
+ *     const query = new Query();
  *     query.update({}, { $set: { a: 5 } });
  *     query.getUpdate(); // { $set: { a: 5 } }
  *
@@ -1500,7 +1500,7 @@ Query.prototype.getUpdate = function() {
  *
  * ####Example:
  *
- *     var query = new Query();
+ *     const query = new Query();
  *     query.update({}, { $set: { a: 5 } });
  *     query.setUpdate({ $set: { b: 6 } });
  *     query.getUpdate(); // { $set: { b: 6 } }
@@ -1801,8 +1801,8 @@ Query.prototype.get = function get(path) {
  * custom errors.
  *
  * ####Example:
- *     var TestSchema = new Schema({ num: Number });
- *     var TestModel = db.model('Test', TestSchema);
+ *     const TestSchema = new Schema({ num: Number });
+ *     const TestModel = db.model('Test', TestSchema);
  *     TestModel.find({ num: 'not a number' }).error(new Error('woops')).exec(function(error) {
  *       // `error` will be a cast error because `num` failed to cast
  *     });
@@ -2162,7 +2162,7 @@ Query.prototype._findOne = wrapThunk(function(callback) {
  *
  * ####Example
  *
- *     var query  = Kitten.where({ color: 'white' });
+ *     const query  = Kitten.where({ color: 'white' });
  *     query.findOne(function (err, kitten) {
  *       if (err) return handleError(err);
  *       if (kitten) {
@@ -2309,7 +2309,7 @@ Query.prototype._estimatedDocumentCount = wrapThunk(function(callback) {
  *
  * ####Example:
  *
- *     var countQuery = model.where({ 'color': 'black' }).count();
+ *     const countQuery = model.where({ 'color': 'black' }).count();
  *
  *     query.count({ color: 'black' }).count(callback)
  *
@@ -3897,7 +3897,7 @@ Query.prototype._replaceOne = wrapThunk(function(callback) {
  *
  * The operation is only executed when a callback is passed. To force execution without a callback, we must first call update() and then execute it by using the `exec()` method.
  *
- *     var q = Model.where({ _id: id });
+ *     const q = Model.where({ _id: id });
  *     q.update({ $set: { name: 'bob' }}).update(); // not executed
  *
  *     q.update({ $set: { name: 'bob' }}).exec(); // executed
@@ -3907,11 +3907,11 @@ Query.prototype._replaceOne = wrapThunk(function(callback) {
  *     q.update({ name: 'bob' }).exec();
  *
  *     // overwriting with empty docs
- *     var q = Model.where({ _id: id }).setOptions({ overwrite: true })
+ *     const q = Model.where({ _id: id }).setOptions({ overwrite: true })
  *     q.update({ }, callback); // executes
  *
  *     // multi update with overwrite to empty doc
- *     var q = Model.where({ _id: id });
+ *     const q = Model.where({ _id: id });
  *     q.setOptions({ multi: true, overwrite: true })
  *     q.update({ });
  *     q.update(callback); // executed
@@ -4349,8 +4349,8 @@ function _orFailError(err, query) {
  *
  * ####Examples:
  *
- *     var promise = query.exec();
- *     var promise = query.exec('update');
+ *     const promise = query.exec();
+ *     const promise = query.exec('update');
  *
  *     query.exec(callback);
  *     query.exec('find', callback);
@@ -4877,7 +4877,7 @@ Query.prototype._applyPaths = function applyPaths() {
  *
  *     // Or you can use `.next()` to manually get the next doc in the stream.
  *     // `.next()` returns a promise, so you can use promises or callbacks.
- *     var cursor = Thing.find({ name: /^hello/ }).cursor();
+ *     const cursor = Thing.find({ name: /^hello/ }).cursor();
  *     cursor.next(function(error, doc) {
  *       console.log(doc);
  *     });
@@ -5021,15 +5021,15 @@ Query.prototype.tailable = function(val, opts) {
  *
  * ####Example
  *
- *     var polyA = [[[ 10, 20 ], [ 10, 40 ], [ 30, 40 ], [ 30, 20 ]]]
+ *     const polyA = [[[ 10, 20 ], [ 10, 40 ], [ 30, 40 ], [ 30, 20 ]]]
  *     query.where('loc').within().geometry({ type: 'Polygon', coordinates: polyA })
  *
  *     // or
- *     var polyB = [[ 0, 0 ], [ 1, 1 ]]
+ *     const polyB = [[ 0, 0 ], [ 1, 1 ]]
  *     query.where('loc').within().geometry({ type: 'LineString', coordinates: polyB })
  *
  *     // or
- *     var polyC = [ 0, 0 ]
+ *     const polyC = [ 0, 0 ]
  *     query.where('loc').within().geometry({ type: 'Point', coordinates: polyC })
  *
  *     // or
@@ -5222,8 +5222,8 @@ if (Symbol.asyncIterator != null) {
  *
  * ####Example
  *
- *     var lowerLeft = [40.73083, -73.99756]
- *     var upperRight= [40.741404,  -73.988135]
+ *     const lowerLeft = [40.73083, -73.99756]
+ *     const upperRight= [40.741404,  -73.988135]
  *
  *     query.where('loc').within().box(lowerLeft, upperRight)
  *     query.box({ ll : lowerLeft, ur : upperRight })
@@ -5259,13 +5259,13 @@ Query.prototype.box = function(ll, ur) {
  *
  * ####Example
  *
- *     var area = { center: [50, 50], radius: 10, unique: true }
+ *     const area = { center: [50, 50], radius: 10, unique: true }
  *     query.where('loc').within().circle(area)
  *     // alternatively
  *     query.circle('loc', area);
  *
  *     // spherical calculations
- *     var area = { center: [50, 50], radius: 10, unique: true, spherical: true }
+ *     const area = { center: [50, 50], radius: 10, unique: true, spherical: true }
  *     query.where('loc').within().circle(area)
  *     // alternatively
  *     query.circle('loc', area);
@@ -5304,7 +5304,7 @@ Query.prototype.center = Query.base.circle;
  *
  * ####Example
  *
- *     var area = { center: [50, 50], radius: 10 };
+ *     const area = { center: [50, 50], radius: 10 };
  *     query.where('loc').within().centerSphere(area);
  *
  * @deprecated
diff --git a/lib/schema.js b/lib/schema.js
index 72410395747..d820f5eaffe 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -41,9 +41,9 @@ let id = 0;
  *
  * ####Example:
  *
- *     var child = new Schema({ name: String });
- *     var schema = new Schema({ name: String, age: Number, children: [child] });
- *     var Tree = mongoose.model('Tree', schema);
+ *     const child = new Schema({ name: String });
+ *     const schema = new Schema({ name: String, age: Number, children: [child] });
+ *     const Tree = mongoose.model('Tree', schema);
  *
  *     // setting schema options
  *     new Schema({ name: String }, { _id: false, autoIndex: false })
@@ -228,7 +228,7 @@ Object.defineProperty(Schema.prototype, 'childSchemas', {
  *
  * ####Example:
  *
- *     var schema = new Schema({ a: String }).add({ b: String });
+ *     const schema = new Schema({ a: String }).add({ b: String });
  *     schema.obj; // { a: String }
  *
  * @api public
@@ -565,7 +565,7 @@ Schema.prototype.add = function add(obj, prefix) {
  *
  * _NOTE:_ Use of these terms as method names is permitted, but play at your own risk, as they may be existing mongoose document methods you are stomping on.
  *
- *      var schema = new Schema(..);
+ *      const schema = new Schema(..);
  *      schema.methods.init = function () {} // potentially breaking
  */
 
@@ -1366,7 +1366,7 @@ Schema.prototype.queue = function(name, args) {
  *
  * ####Example
  *
- *     var toySchema = new Schema({ name: String, created: Date });
+ *     const toySchema = new Schema({ name: String, created: Date });
  *
  *     toySchema.pre('save', function(next) {
  *       if (!this.created) this.created = new Date;
@@ -1428,7 +1428,7 @@ Schema.prototype.pre = function(name) {
 /**
  * Defines a post hook for the document
  *
- *     var schema = new Schema(..);
+ *     const schema = new Schema(..);
  *     schema.post('save', function (doc) {
  *       console.log('this fired after a document was saved');
  *     });
@@ -1441,9 +1441,9 @@ Schema.prototype.pre = function(name) {
  *       console.log('this fired after you ran `updateMany()` or `deleteMany()`);
  *     });
  *
- *     var Model = mongoose.model('Model', schema);
+ *     const Model = mongoose.model('Model', schema);
  *
- *     var m = new Model(..);
+ *     const m = new Model(..);
  *     m.save(function(err) {
  *       console.log('this fires after the `post` hook');
  *     });
@@ -1522,15 +1522,15 @@ Schema.prototype.plugin = function(fn, opts) {
  *
  * ####Example
  *
- *     var schema = kittySchema = new Schema(..);
+ *     const schema = kittySchema = new Schema(..);
  *
  *     schema.method('meow', function () {
  *       console.log('meeeeeoooooooooooow');
  *     })
  *
- *     var Kitty = mongoose.model('Kitty', schema);
+ *     const Kitty = mongoose.model('Kitty', schema);
  *
- *     var fizz = new Kitty;
+ *     const fizz = new Kitty;
  *     fizz.meow(); // meeeeeooooooooooooow
  *
  * If a hash of name/fn pairs is passed as the only argument, each name/fn pair will be added as methods.
@@ -2198,8 +2198,8 @@ module.exports = exports = Schema;
  *
  * ####Example:
  *
- *     var mongoose = require('mongoose');
- *     var ObjectId = mongoose.Schema.Types.ObjectId;
+ *     const mongoose = require('mongoose');
+ *     const ObjectId = mongoose.Schema.Types.ObjectId;
  *
  * ####Types:
  *
@@ -2214,7 +2214,7 @@ module.exports = exports = Schema;
  *
  * Using this exposed access to the `Mixed` SchemaType, we can use them in our schema.
  *
- *     var Mixed = mongoose.Schema.Types.Mixed;
+ *     const Mixed = mongoose.Schema.Types.Mixed;
  *     new mongoose.Schema({ _user: Mixed })
  *
  * @api public
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 631d18fcb3d..c5b8cb7a114 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -213,9 +213,9 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
  *
  * ####Example:
  *
- *     var s = new Schema({ uuid: { type: Buffer, subtype: 4 });
- *     var M = db.model('M', s);
- *     var m = new M({ uuid: 'test string' });
+ *     const s = new Schema({ uuid: { type: Buffer, subtype: 4 });
+ *     const M = db.model('M', s);
+ *     const m = new M({ uuid: 'test string' });
  *     m.uuid._subtype; // 4
  *
  * @param {Number} subtype the default subtype
diff --git a/lib/schema/date.js b/lib/schema/date.js
index ebeaf472237..4b9ad1cde1e 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -131,7 +131,7 @@ SchemaDate.cast = function cast(caster) {
  *     new Schema({ createdAt: { type: Date, expires: '1.5h' }});
  *
  *     // expire in 7 days
- *     var schema = new Schema({ createdAt: Date });
+ *     const schema = new Schema({ createdAt: Date });
  *     schema.path('createdAt').expires('7d');
  *
  * @param {Number|String} when
@@ -205,9 +205,9 @@ SchemaDate.prototype.checkRequired = function(value, doc) {
  *
  * ####Example:
  *
- *     var s = new Schema({ d: { type: Date, min: Date('1970-01-01') })
- *     var M = db.model('M', s)
- *     var m = new M({ d: Date('1969-12-31') })
+ *     const s = new Schema({ d: { type: Date, min: Date('1970-01-01') })
+ *     const M = db.model('M', s)
+ *     const m = new M({ d: Date('1969-12-31') })
  *     m.save(function (err) {
  *       console.error(err) // validator error
  *       m.d = Date('2014-12-08');
@@ -216,10 +216,10 @@ SchemaDate.prototype.checkRequired = function(value, doc) {
  *
  *     // custom error messages
  *     // We can also use the special {MIN} token which will be replaced with the invalid value
- *     var min = [Date('1970-01-01'), 'The value of path `{PATH}` ({VALUE}) is beneath the limit ({MIN}).'];
- *     var schema = new Schema({ d: { type: Date, min: min })
- *     var M = mongoose.model('M', schema);
- *     var s= new M({ d: Date('1969-12-31') });
+ *     const min = [Date('1970-01-01'), 'The value of path `{PATH}` ({VALUE}) is beneath the limit ({MIN}).'];
+ *     const schema = new Schema({ d: { type: Date, min: min })
+ *     const M = mongoose.model('M', schema);
+ *     const s= new M({ d: Date('1969-12-31') });
  *     s.validate(function (err) {
  *       console.log(String(err)) // ValidationError: The value of path `d` (1969-12-31) is before the limit (1970-01-01).
  *     })
@@ -267,9 +267,9 @@ SchemaDate.prototype.min = function(value, message) {
  *
  * ####Example:
  *
- *     var s = new Schema({ d: { type: Date, max: Date('2014-01-01') })
- *     var M = db.model('M', s)
- *     var m = new M({ d: Date('2014-12-08') })
+ *     const s = new Schema({ d: { type: Date, max: Date('2014-01-01') })
+ *     const M = db.model('M', s)
+ *     const m = new M({ d: Date('2014-12-08') })
  *     m.save(function (err) {
  *       console.error(err) // validator error
  *       m.d = Date('2013-12-31');
@@ -278,10 +278,10 @@ SchemaDate.prototype.min = function(value, message) {
  *
  *     // custom error messages
  *     // We can also use the special {MAX} token which will be replaced with the invalid value
- *     var max = [Date('2014-01-01'), 'The value of path `{PATH}` ({VALUE}) exceeds the limit ({MAX}).'];
- *     var schema = new Schema({ d: { type: Date, max: max })
- *     var M = mongoose.model('M', schema);
- *     var s= new M({ d: Date('2014-12-08') });
+ *     const max = [Date('2014-01-01'), 'The value of path `{PATH}` ({VALUE}) exceeds the limit ({MAX}).'];
+ *     const schema = new Schema({ d: { type: Date, max: max })
+ *     const M = mongoose.model('M', schema);
+ *     const s= new M({ d: Date('2014-12-08') });
  *     s.validate(function (err) {
  *       console.log(String(err)) // ValidationError: The value of path `d` (2014-12-08) exceeds the limit (2014-01-01).
  *     })
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 0b532bc29cc..719a1aa80f2 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -179,9 +179,9 @@ SchemaNumber.prototype.checkRequired = function checkRequired(value, doc) {
  *
  * ####Example:
  *
- *     var s = new Schema({ n: { type: Number, min: 10 })
- *     var M = db.model('M', s)
- *     var m = new M({ n: 9 })
+ *     const s = new Schema({ n: { type: Number, min: 10 })
+ *     const M = db.model('M', s)
+ *     const m = new M({ n: 9 })
  *     m.save(function (err) {
  *       console.error(err) // validator error
  *       m.n = 10;
@@ -190,10 +190,10 @@ SchemaNumber.prototype.checkRequired = function checkRequired(value, doc) {
  *
  *     // custom error messages
  *     // We can also use the special {MIN} token which will be replaced with the invalid value
- *     var min = [10, 'The value of path `{PATH}` ({VALUE}) is beneath the limit ({MIN}).'];
- *     var schema = new Schema({ n: { type: Number, min: min })
- *     var M = mongoose.model('Measurement', schema);
- *     var s= new M({ n: 4 });
+ *     const min = [10, 'The value of path `{PATH}` ({VALUE}) is beneath the limit ({MIN}).'];
+ *     const schema = new Schema({ n: { type: Number, min: min })
+ *     const M = mongoose.model('Measurement', schema);
+ *     const s= new M({ n: 4 });
  *     s.validate(function (err) {
  *       console.log(String(err)) // ValidationError: The value of path `n` (4) is beneath the limit (10).
  *     })
@@ -233,9 +233,9 @@ SchemaNumber.prototype.min = function(value, message) {
  *
  * ####Example:
  *
- *     var s = new Schema({ n: { type: Number, max: 10 })
- *     var M = db.model('M', s)
- *     var m = new M({ n: 11 })
+ *     const s = new Schema({ n: { type: Number, max: 10 })
+ *     const M = db.model('M', s)
+ *     const m = new M({ n: 11 })
  *     m.save(function (err) {
  *       console.error(err) // validator error
  *       m.n = 10;
@@ -244,10 +244,10 @@ SchemaNumber.prototype.min = function(value, message) {
  *
  *     // custom error messages
  *     // We can also use the special {MAX} token which will be replaced with the invalid value
- *     var max = [10, 'The value of path `{PATH}` ({VALUE}) exceeds the limit ({MAX}).'];
- *     var schema = new Schema({ n: { type: Number, max: max })
- *     var M = mongoose.model('Measurement', schema);
- *     var s= new M({ n: 4 });
+ *     const max = [10, 'The value of path `{PATH}` ({VALUE}) exceeds the limit ({MAX}).'];
+ *     const schema = new Schema({ n: { type: Number, max: max })
+ *     const M = mongoose.model('Measurement', schema);
+ *     const s= new M({ n: 4 });
  *     s.validate(function (err) {
  *       console.log(String(err)) // ValidationError: The value of path `n` (4) exceeds the limit (10).
  *     })
@@ -287,10 +287,10 @@ SchemaNumber.prototype.max = function(value, message) {
  *
  * ####Example:
  *
- *     var s = new Schema({ n: { type: Number, enum: [1, 2, 3] });
- *     var M = db.model('M', s);
+ *     const s = new Schema({ n: { type: Number, enum: [1, 2, 3] });
+ *     const M = db.model('M', s);
  *
- *     var m = new M({ n: 4 });
+ *     const m = new M({ n: 4 });
  *     await m.save(); // throws validation error
  *
  *     m.n = 3;
diff --git a/lib/schema/string.js b/lib/schema/string.js
index 746900d706c..a3bfaf4ea57 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -171,10 +171,10 @@ SchemaString.checkRequired = SchemaType.checkRequired;
  *
  * ####Example:
  *
- *     var states = ['opening', 'open', 'closing', 'closed']
- *     var s = new Schema({ state: { type: String, enum: states }})
- *     var M = db.model('M', s)
- *     var m = new M({ state: 'invalid' })
+ *     const states = ['opening', 'open', 'closing', 'closed']
+ *     const s = new Schema({ state: { type: String, enum: states }})
+ *     const M = db.model('M', s)
+ *     const m = new M({ state: 'invalid' })
  *     m.save(function (err) {
  *       console.error(String(err)) // ValidationError: `invalid` is not a valid enum value for path `state`.
  *       m.state = 'open'
@@ -182,13 +182,13 @@ SchemaString.checkRequired = SchemaType.checkRequired;
  *     })
  *
  *     // or with custom error messages
- *     var enum = {
+ *     const enum = {
  *       values: ['opening', 'open', 'closing', 'closed'],
  *       message: 'enum validator failed for path `{PATH}` with value `{VALUE}`'
  *     }
- *     var s = new Schema({ state: { type: String, enum: enum })
- *     var M = db.model('M', s)
- *     var m = new M({ state: 'invalid' })
+ *     const s = new Schema({ state: { type: String, enum: enum })
+ *     const M = db.model('M', s)
+ *     const m = new M({ state: 'invalid' })
  *     m.save(function (err) {
  *       console.error(String(err)) // ValidationError: enum validator failed for path `state` with value `invalid`
  *       m.state = 'open'
@@ -249,9 +249,9 @@ SchemaString.prototype.enum = function() {
  *
  * ####Example:
  *
- *     var s = new Schema({ email: { type: String, lowercase: true }})
- *     var M = db.model('M', s);
- *     var m = new M({ email: 'SomeEmail@example.COM' });
+ *     const s = new Schema({ email: { type: String, lowercase: true }})
+ *     const M = db.model('M', s);
+ *     const m = new M({ email: 'SomeEmail@example.COM' });
  *     console.log(m.email) // someemail@example.com
  *     M.find({ email: 'SomeEmail@example.com' }); // Queries by 'someemail@example.com'
  *
@@ -287,9 +287,9 @@ SchemaString.prototype.lowercase = function(shouldApply) {
  *
  * ####Example:
  *
- *     var s = new Schema({ caps: { type: String, uppercase: true }})
- *     var M = db.model('M', s);
- *     var m = new M({ caps: 'an example' });
+ *     const s = new Schema({ caps: { type: String, uppercase: true }})
+ *     const M = db.model('M', s);
+ *     const m = new M({ caps: 'an example' });
  *     console.log(m.caps) // AN EXAMPLE
  *     M.find({ caps: 'an example' }) // Matches documents where caps = 'AN EXAMPLE'
  *
@@ -325,11 +325,11 @@ SchemaString.prototype.uppercase = function(shouldApply) {
  *
  * ####Example:
  *
- *     var s = new Schema({ name: { type: String, trim: true }});
- *     var M = db.model('M', s);
- *     var string = ' some name ';
+ *     const s = new Schema({ name: { type: String, trim: true }});
+ *     const M = db.model('M', s);
+ *     const string = ' some name ';
  *     console.log(string.length); // 11
- *     var m = new M({ name: string });
+ *     const m = new M({ name: string });
  *     console.log(m.name.length); // 9
  *
  *     // Equivalent to `findOne({ name: string.trim() })`
@@ -365,9 +365,9 @@ SchemaString.prototype.trim = function(shouldTrim) {
  *
  * ####Example:
  *
- *     var schema = new Schema({ postalCode: { type: String, minlength: 5 })
- *     var Address = db.model('Address', schema)
- *     var address = new Address({ postalCode: '9512' })
+ *     const schema = new Schema({ postalCode: { type: String, minlength: 5 })
+ *     const Address = db.model('Address', schema)
+ *     const address = new Address({ postalCode: '9512' })
  *     address.save(function (err) {
  *       console.error(err) // validator error
  *       address.postalCode = '95125';
@@ -376,10 +376,10 @@ SchemaString.prototype.trim = function(shouldTrim) {
  *
  *     // custom error messages
  *     // We can also use the special {MINLENGTH} token which will be replaced with the minimum allowed length
- *     var minlength = [5, 'The value of path `{PATH}` (`{VALUE}`) is shorter than the minimum allowed length ({MINLENGTH}).'];
- *     var schema = new Schema({ postalCode: { type: String, minlength: minlength })
- *     var Address = mongoose.model('Address', schema);
- *     var address = new Address({ postalCode: '9512' });
+ *     const minlength = [5, 'The value of path `{PATH}` (`{VALUE}`) is shorter than the minimum allowed length ({MINLENGTH}).'];
+ *     const schema = new Schema({ postalCode: { type: String, minlength: minlength })
+ *     const Address = mongoose.model('Address', schema);
+ *     const address = new Address({ postalCode: '9512' });
  *     address.validate(function (err) {
  *       console.log(String(err)) // ValidationError: The value of path `postalCode` (`9512`) is shorter than the minimum length (5).
  *     })
@@ -419,9 +419,9 @@ SchemaString.prototype.minlength = function(value, message) {
  *
  * ####Example:
  *
- *     var schema = new Schema({ postalCode: { type: String, maxlength: 9 })
- *     var Address = db.model('Address', schema)
- *     var address = new Address({ postalCode: '9512512345' })
+ *     const schema = new Schema({ postalCode: { type: String, maxlength: 9 })
+ *     const Address = db.model('Address', schema)
+ *     const address = new Address({ postalCode: '9512512345' })
  *     address.save(function (err) {
  *       console.error(err) // validator error
  *       address.postalCode = '95125';
@@ -430,10 +430,10 @@ SchemaString.prototype.minlength = function(value, message) {
  *
  *     // custom error messages
  *     // We can also use the special {MAXLENGTH} token which will be replaced with the maximum allowed length
- *     var maxlength = [9, 'The value of path `{PATH}` (`{VALUE}`) exceeds the maximum allowed length ({MAXLENGTH}).'];
- *     var schema = new Schema({ postalCode: { type: String, maxlength: maxlength })
- *     var Address = mongoose.model('Address', schema);
- *     var address = new Address({ postalCode: '9512512345' });
+ *     const maxlength = [9, 'The value of path `{PATH}` (`{VALUE}`) exceeds the maximum allowed length ({MAXLENGTH}).'];
+ *     const schema = new Schema({ postalCode: { type: String, maxlength: maxlength })
+ *     const Address = mongoose.model('Address', schema);
+ *     const address = new Address({ postalCode: '9512512345' });
  *     address.validate(function (err) {
  *       console.log(String(err)) // ValidationError: The value of path `postalCode` (`9512512345`) exceeds the maximum allowed length (9).
  *     })
@@ -475,9 +475,9 @@ SchemaString.prototype.maxlength = function(value, message) {
  *
  * ####Example:
  *
- *     var s = new Schema({ name: { type: String, match: /^a/ }})
- *     var M = db.model('M', s)
- *     var m = new M({ name: 'I am invalid' })
+ *     const s = new Schema({ name: { type: String, match: /^a/ }})
+ *     const M = db.model('M', s)
+ *     const m = new M({ name: 'I am invalid' })
  *     m.validate(function (err) {
  *       console.error(String(err)) // "ValidationError: Path `name` is invalid (I am invalid)."
  *       m.name = 'apples'
@@ -487,17 +487,17 @@ SchemaString.prototype.maxlength = function(value, message) {
  *     })
  *
  *     // using a custom error message
- *     var match = [ /\.html$/, "That file doesn't end in .html ({VALUE})" ];
- *     var s = new Schema({ file: { type: String, match: match }})
- *     var M = db.model('M', s);
- *     var m = new M({ file: 'invalid' });
+ *     const match = [ /\.html$/, "That file doesn't end in .html ({VALUE})" ];
+ *     const s = new Schema({ file: { type: String, match: match }})
+ *     const M = db.model('M', s);
+ *     const m = new M({ file: 'invalid' });
  *     m.validate(function (err) {
  *       console.log(String(err)) // "ValidationError: That file doesn't end in .html (invalid)"
  *     })
  *
  * Empty strings, `undefined`, and `null` values always pass the match validator. If you require these values, enable the `required` validator also.
  *
- *     var s = new Schema({ name: { type: String, match: /^a/, required: true }})
+ *     const s = new Schema({ name: { type: String, match: /^a/, required: true }})
  *
  * @param {RegExp} regExp regular expression to test against
  * @param {String} [message] optional custom error message
diff --git a/lib/schematype.js b/lib/schematype.js
index 38a3d3dbe8c..6c3a29c9a89 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -204,9 +204,9 @@ SchemaType.get = function(getter) {
  *
  * ####Example:
  *
- *     var schema = new Schema({ n: { type: Number, default: 10 })
- *     var M = db.model('M', schema)
- *     var m = new M;
+ *     const schema = new Schema({ n: { type: Number, default: 10 })
+ *     const M = db.model('M', schema)
+ *     const m = new M;
  *     console.log(m.n) // 10
  *
  * Defaults can be either `functions` which return the value to use as the default or the literal value itself. Either way, the value will be cast based on its schema type before being set during document creation.
@@ -214,13 +214,13 @@ SchemaType.get = function(getter) {
  * ####Example:
  *
  *     // values are cast:
- *     var schema = new Schema({ aNumber: { type: Number, default: 4.815162342 }})
- *     var M = db.model('M', schema)
- *     var m = new M;
+ *     const schema = new Schema({ aNumber: { type: Number, default: 4.815162342 }})
+ *     const M = db.model('M', schema)
+ *     const m = new M;
  *     console.log(m.aNumber) // 4.815162342
  *
  *     // default unique objects for Mixed types:
- *     var schema = new Schema({ mixed: Schema.Types.Mixed });
+ *     const schema = new Schema({ mixed: Schema.Types.Mixed });
  *     schema.path('mixed').default(function () {
  *       return {};
  *     });
@@ -228,13 +228,13 @@ SchemaType.get = function(getter) {
  *     // if we don't use a function to return object literals for Mixed defaults,
  *     // each document will receive a reference to the same object literal creating
  *     // a "shared" object instance:
- *     var schema = new Schema({ mixed: Schema.Types.Mixed });
+ *     const schema = new Schema({ mixed: Schema.Types.Mixed });
  *     schema.path('mixed').default({});
- *     var M = db.model('M', schema);
- *     var m1 = new M;
+ *     const M = db.model('M', schema);
+ *     const m1 = new M;
  *     m1.mixed.added = 1;
  *     console.log(m1.mixed); // { added: 1 }
- *     var m2 = new M;
+ *     const m2 = new M;
  *     console.log(m2.mixed); // { added: 1 }
  *
  * @param {Function|any} val the default value
@@ -267,11 +267,11 @@ SchemaType.prototype.default = function(val) {
  *
  * ####Example:
  *
- *     var s = new Schema({ name: { type: String, index: true })
- *     var s = new Schema({ loc: { type: [Number], index: 'hashed' })
- *     var s = new Schema({ loc: { type: [Number], index: '2d', sparse: true })
- *     var s = new Schema({ loc: { type: [Number], index: { type: '2dsphere', sparse: true }})
- *     var s = new Schema({ date: { type: Date, index: { unique: true, expires: '1d' }})
+ *     const s = new Schema({ name: { type: String, index: true })
+ *     const s = new Schema({ loc: { type: [Number], index: 'hashed' })
+ *     const s = new Schema({ loc: { type: [Number], index: '2d', sparse: true })
+ *     const s = new Schema({ loc: { type: [Number], index: { type: '2dsphere', sparse: true }})
+ *     const s = new Schema({ date: { type: Date, index: { unique: true, expires: '1d' }})
  *     s.path('my.path').index(true);
  *     s.path('my.date').index({ expires: 60 });
  *     s.path('my.path').index({ unique: true, sparse: true });
@@ -299,7 +299,7 @@ SchemaType.prototype.index = function(options) {
  *
  * ####Example:
  *
- *     var s = new Schema({ name: { type: String, unique: true }});
+ *     const s = new Schema({ name: { type: String, unique: true }});
  *     s.path('name').index({ unique: true });
  *
  * _NOTE: violating the constraint returns an `E11000` error from MongoDB when saving, not a Mongoose validation error._
@@ -332,7 +332,7 @@ SchemaType.prototype.unique = function(bool) {
  *
  * ###Example:
  *
- *      var s = new Schema({name : {type: String, text : true })
+ *      const s = new Schema({name : {type: String, text : true })
  *      s.path('name').index({text : true});
  * @param {Boolean} bool
  * @return {SchemaType} this
@@ -364,7 +364,7 @@ SchemaType.prototype.text = function(bool) {
  *
  * ####Example:
  *
- *     var s = new Schema({ name: { type: String, sparse: true } });
+ *     const s = new Schema({ name: { type: String, sparse: true } });
  *     s.path('name').index({ sparse: true });
  *
  * @param {Boolean} bool
@@ -484,10 +484,10 @@ SchemaType.prototype.transform = function(fn) {
  *     }
  *
  *     // defining within the schema
- *     var s = new Schema({ name: { type: String, set: capitalize }});
+ *     const s = new Schema({ name: { type: String, set: capitalize }});
  *
  *     // or with the SchemaType
- *     var s = new Schema({ name: String })
+ *     const s = new Schema({ name: String })
  *     s.path('name').set(capitalize);
  *
  * Setters allow you to transform the data before it gets to the raw mongodb
@@ -504,17 +504,17 @@ SchemaType.prototype.transform = function(fn) {
  *       return v.toLowerCase();
  *     }
  *
- *     var UserSchema = new Schema({
+ *     const UserSchema = new Schema({
  *       email: { type: String, set: toLower }
  *     });
  *
- *     var User = db.model('User', UserSchema);
+ *     const User = db.model('User', UserSchema);
  *
- *     var user = new User({email: 'AVENUE@Q.COM'});
+ *     const user = new User({email: 'AVENUE@Q.COM'});
  *     console.log(user.email); // 'avenue@q.com'
  *
  *     // or
- *     var user = new User();
+ *     const user = new User();
  *     user.email = 'Avenue@Q.com';
  *     console.log(user.email); // 'avenue@q.com'
  *     User.updateOne({ _id: _id }, { $set: { email: 'AVENUE@Q.COM' } }); // update to 'avenue@q.com'
@@ -536,13 +536,13 @@ SchemaType.prototype.transform = function(fn) {
  *       }
  *     }
  *
- *     var VirusSchema = new Schema({
+ *     const VirusSchema = new Schema({
  *       name: { type: String, required: true, set: inspector },
  *       taxonomy: { type: String, set: inspector }
  *     })
  *
- *     var Virus = db.model('Virus', VirusSchema);
- *     var v = new Virus({ name: 'Parvoviridae', taxonomy: 'Parvovirinae' });
+ *     const Virus = db.model('Virus', VirusSchema);
+ *     const v = new Virus({ name: 'Parvoviridae', taxonomy: 'Parvovirinae' });
  *
  *     console.log(v.name);     // name is required
  *     console.log(v.taxonomy); // Parvovirinae
@@ -589,10 +589,10 @@ SchemaType.prototype.set = function(fn) {
  *     }
  *
  *     // defining within the schema
- *     var s = new Schema({ born: { type: Date, get: dob })
+ *     const s = new Schema({ born: { type: Date, get: dob })
  *
  *     // or by retreiving its SchemaType
- *     var s = new Schema({ born: Date })
+ *     const s = new Schema({ born: Date })
  *     s.path('born').get(dob)
  *
  * Getters allow you to transform the representation of the data as it travels from the raw mongodb document to the value that you see.
@@ -603,11 +603,11 @@ SchemaType.prototype.set = function(fn) {
  *       return '****-****-****-' + cc.slice(cc.length-4, cc.length);
  *     }
  *
- *     var AccountSchema = new Schema({
+ *     const AccountSchema = new Schema({
  *       creditCardNumber: { type: String, get: obfuscate }
  *     });
  *
- *     var Account = db.model('Account', AccountSchema);
+ *     const Account = db.model('Account', AccountSchema);
  *
  *     Account.findById(id, function (err, found) {
  *       console.log(found.creditCardNumber); // '****-****-****-1234'
@@ -623,12 +623,12 @@ SchemaType.prototype.set = function(fn) {
  *       }
  *     }
  *
- *     var VirusSchema = new Schema({
+ *     const VirusSchema = new Schema({
  *       name: { type: String, required: true, get: inspector },
  *       taxonomy: { type: String, get: inspector }
  *     })
  *
- *     var Virus = db.model('Virus', VirusSchema);
+ *     const Virus = db.model('Virus', VirusSchema);
  *
  *     Virus.findById(id, function (err, virus) {
  *       console.log(virus.name);     // name is required
@@ -667,12 +667,12 @@ SchemaType.prototype.get = function(fn) {
  *
  *     // with a custom error message
  *
- *     var custom = [validator, 'Uh oh, {PATH} does not equal "something".']
+ *     const custom = [validator, 'Uh oh, {PATH} does not equal "something".']
  *     new Schema({ name: { type: String, validate: custom }});
  *
  *     // adding many validators at a time
  *
- *     var many = [
+ *     const many = [
  *         { validator: validator, msg: 'uh oh' }
  *       , { validator: anotherValidator, msg: 'failed' }
  *     ]
@@ -680,7 +680,7 @@ SchemaType.prototype.get = function(fn) {
  *
  *     // or utilizing SchemaType methods directly:
  *
- *     var schema = new Schema({ name: 'string' });
+ *     const schema = new Schema({ name: 'string' });
  *     schema.path('name').validate(validator, 'validation of `{PATH}` failed with value `{VALUE}`');
  *
  * ####Error message templates:
@@ -730,11 +730,11 @@ SchemaType.prototype.get = function(fn) {
  *
  * If validation fails during `pre('save')` and no callback was passed to receive the error, an `error` event will be emitted on your Models associated db [connection](#connection_Connection), passing the validation error object along.
  *
- *     var conn = mongoose.createConnection(..);
+ *     const conn = mongoose.createConnection(..);
  *     conn.on('error', handleError);
  *
- *     var Product = conn.model('Product', yourSchema);
- *     var dvd = new Product(..);
+ *     const Product = conn.model('Product', yourSchema);
+ *     const dvd = new Product(..);
  *     dvd.save(); // emits error on the `conn` above
  *
  * If you want to handle these errors at the Model level, add an `error`
@@ -818,15 +818,15 @@ const handleIsAsync = util.deprecate(function handleIsAsync() {},
  *
  * ####Example:
  *
- *     var s = new Schema({ born: { type: Date, required: true })
+ *     const s = new Schema({ born: { type: Date, required: true })
  *
  *     // or with custom error message
  *
- *     var s = new Schema({ born: { type: Date, required: '{PATH} is required!' })
+ *     const s = new Schema({ born: { type: Date, required: '{PATH} is required!' })
  *
  *     // or with a function
  *
- *     var s = new Schema({
+ *     const s = new Schema({
  *       userId: ObjectId,
  *       username: {
  *         type: String,
@@ -835,7 +835,7 @@ const handleIsAsync = util.deprecate(function handleIsAsync() {},
  *     })
  *
  *     // or with a function and a custom message
- *     var s = new Schema({
+ *     const s = new Schema({
  *       userId: ObjectId,
  *       username: {
  *         type: String,
@@ -855,7 +855,7 @@ const handleIsAsync = util.deprecate(function handleIsAsync() {},
  *     s.path('name').required(true, 'grrr :( ');
  *
  *     // or make a path conditionally required based on a function
- *     var isOver18 = function() { return this.age >= 18; };
+ *     const isOver18 = function() { return this.age >= 18; };
  *     s.path('voterRegistrationId').required(isOver18);
  *
  * The required validator uses the SchemaType's `checkRequired` function to
diff --git a/lib/types/buffer.js b/lib/types/buffer.js
index 6fb905b4a16..9bac2e8c506 100644
--- a/lib/types/buffer.js
+++ b/lib/types/buffer.js
@@ -168,7 +168,7 @@ MongooseBuffer.mixin = {
  *
  * ####SubTypes:
  *
- *   var bson = require('bson')
+ *   const bson = require('bson')
  *   bson.BSON_BINARY_SUBTYPE_DEFAULT
  *   bson.BSON_BINARY_SUBTYPE_FUNCTION
  *   bson.BSON_BINARY_SUBTYPE_BYTE_ARRAY
@@ -238,7 +238,7 @@ MongooseBuffer.mixin.equals = function(other) {
  *
  * ####SubTypes:
  *
- *   var bson = require('bson')
+ *   const bson = require('bson')
  *   bson.BSON_BINARY_SUBTYPE_DEFAULT
  *   bson.BSON_BINARY_SUBTYPE_FUNCTION
  *   bson.BSON_BINARY_SUBTYPE_BYTE_ARRAY
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 2e1c5c75ecd..954df521cc7 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -123,7 +123,7 @@ class CoreMongooseArray extends Array {
    *
    *      doc.array = [1,2,3];
    *
-   *      var shifted = doc.array.$shift();
+   *      const shifted = doc.array.$shift();
    *      console.log(shifted); // 1
    *      console.log(doc.array); // [2,3]
    *
@@ -170,7 +170,7 @@ class CoreMongooseArray extends Array {
    *
    *      doc.array = [1,2,3];
    *
-   *      var popped = doc.array.$pop();
+   *      const popped = doc.array.$pop();
    *      console.log(popped); // 3
    *      console.log(doc.array); // [1,2]
    *
@@ -389,7 +389,7 @@ class CoreMongooseArray extends Array {
    * ####Example:
    *
    *     console.log(doc.array) // [2,3,4]
-   *     var added = doc.array.addToSet(4,5);
+   *     const added = doc.array.addToSet(4,5);
    *     console.log(doc.array) // [2,3,4,5]
    *     console.log(added)     // [5]
    *
@@ -723,9 +723,9 @@ class CoreMongooseArray extends Array {
    * ####Example:
    *
    *     // given documents based on the following
-   *     var Doc = mongoose.model('Doc', new Schema({ array: [Number] }));
+   *     const Doc = mongoose.model('Doc', new Schema({ array: [Number] }));
    *
-   *     var doc = new Doc({ array: [2,3,4] })
+   *     const doc = new Doc({ array: [2,3,4] })
    *
    *     console.log(doc.array) // [2,3,4]
    *
@@ -757,7 +757,7 @@ class CoreMongooseArray extends Array {
    * ####Example:
    *
    *     doc.array = [2,3];
-   *     var res = doc.array.shift();
+   *     const res = doc.array.shift();
    *     console.log(res) // 2
    *     console.log(doc.array) // [3]
    *
diff --git a/lib/types/decimal128.js b/lib/types/decimal128.js
index f0bae2a1315..cb08861848c 100644
--- a/lib/types/decimal128.js
+++ b/lib/types/decimal128.js
@@ -3,7 +3,7 @@
  *
  * ####Example
  *
- *     var id = new mongoose.Types.ObjectId;
+ *     const id = new mongoose.Types.ObjectId;
  *
  * @constructor ObjectId
  */
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 0ae4ed03a29..2855ae4ff15 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -114,7 +114,7 @@ class CoreDocumentArray extends CoreMongooseArray {
    *
    * ####Example:
    *
-   *     var embeddedDoc = m.array.id(some_id);
+   *     const embeddedDoc = m.array.id(some_id);
    *
    * @return {EmbeddedDocument|null} the subdocument or null if not found.
    * @param {ObjectId|String|Number|Buffer} id
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 9c1e1daad2e..d0cfdcfc73a 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -85,7 +85,7 @@ EmbeddedDocument.prototype.$setIndex = function(index) {
  *
  * ####Example:
  *
- *     var doc = blogpost.comments.id(hexstring);
+ *     const doc = blogpost.comments.id(hexstring);
  *     doc.mixed.type = 'changed';
  *     doc.markModified('mixed.type');
  *
diff --git a/lib/types/objectid.js b/lib/types/objectid.js
index 4c3f8b4ffa0..19e3d90e8cd 100644
--- a/lib/types/objectid.js
+++ b/lib/types/objectid.js
@@ -3,7 +3,7 @@
  *
  * ####Example
  *
- *     var id = new mongoose.Types.ObjectId;
+ *     const id = new mongoose.Types.ObjectId;
  *
  * @constructor ObjectId
  */
diff --git a/lib/virtualtype.js b/lib/virtualtype.js
index f91438ac22d..35f26b45e7b 100644
--- a/lib/virtualtype.js
+++ b/lib/virtualtype.js
@@ -77,7 +77,7 @@ VirtualType.prototype.clone = function() {
  *
  * ####Example:
  *
- *     var virtual = schema.virtual('fullname');
+ *     const virtual = schema.virtual('fullname');
  *     virtual.get(function(value, virtual, doc) {
  *       return this.name.first + ' ' + this.name.last;
  *     });
@@ -105,7 +105,7 @@ VirtualType.prototype.get = function(fn) {
  *
  *     const virtual = schema.virtual('fullname');
  *     virtual.set(function(value, virtual, doc) {
- *       var parts = value.split(' ');
+ *       const parts = value.split(' ');
  *       this.name.first = parts[0];
  *       this.name.last = parts[1];
  *     });
diff --git a/test/docs/defaults.test.js b/test/docs/defaults.test.js
index 352cd06bec7..b92cf4cf307 100644
--- a/test/docs/defaults.test.js
+++ b/test/docs/defaults.test.js
@@ -27,24 +27,24 @@ describe('defaults docs', function () {
    * strictly `undefined`.
    */
   it('Declaring defaults in your schema', function(done) {
-    var schema = new Schema({
+    const schema = new Schema({
       name: String,
       role: { type: String, default: 'guitarist' }
     });
 
-    var Person = db.model('Person', schema);
+    const Person = db.model('Person', schema);
 
-    var axl = new Person({ name: 'Axl Rose', role: 'singer' });
+    const axl = new Person({ name: 'Axl Rose', role: 'singer' });
     assert.equal(axl.role, 'singer');
 
-    var slash = new Person({ name: 'Slash' });
+    const slash = new Person({ name: 'Slash' });
     assert.equal(slash.role, 'guitarist');
 
-    var izzy = new Person({ name: 'Izzy', role: undefined });
+    const izzy = new Person({ name: 'Izzy', role: undefined });
     assert.equal(izzy.role, 'guitarist');
 
     // Defaults do **not** run on `null`, `''`, or value other than `undefined`.
-    var foo = new Person({ name: 'Bar', role: null });
+    const foo = new Person({ name: 'Bar', role: null });
     assert.strictEqual(foo.role, null);
 
     Person.create(axl, slash, function(error) {
@@ -65,7 +65,7 @@ describe('defaults docs', function () {
    * execute that function and use the return value as the default.
    */
   it('Default functions', function() {
-    var schema = new Schema({
+    const schema = new Schema({
       title: String,
       date: {
         type: Date,
@@ -74,9 +74,9 @@ describe('defaults docs', function () {
       }
     });
 
-    var BlogPost = db.model('BlogPost', schema);
+    const BlogPost = db.model('BlogPost', schema);
 
-    var post = new BlogPost({title: '5 Best Arnold Schwarzenegger Movies'});
+    const post = new BlogPost({title: '5 Best Arnold Schwarzenegger Movies'});
 
     // The post has a default Date set to now
     assert.ok(post.date.getTime() >= Date.now() - 1000);
@@ -97,16 +97,16 @@ describe('defaults docs', function () {
    * using MongoDB server < 2.4.0, do **not** use `setDefaultsOnInsert`.
    */
   it('The `setDefaultsOnInsert` option', function(done) {
-    var schema = new Schema({
+    const schema = new Schema({
       title: String,
       genre: {type: String, default: 'Action'}
     });
 
-    var Movie = db.model('Movie', schema);
+    const Movie = db.model('Movie', schema);
 
-    var query = {};
-    var update = {title: 'The Terminator'};
-    var options = {
+    const query = {};
+    const update = {title: 'The Terminator'};
+    const options = {
       // Return the document after updates are applied
       new: true,
       // Create a document if one isn't found. Required
diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index a0f210cf64f..5c9793e93e4 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -1,20 +1,20 @@
 'use strict';
 
-var assert = require('assert');
-var mongoose = require('../../');
+const assert = require('assert');
+const mongoose = require('../../');
 
-var Schema = mongoose.Schema;
+const Schema = mongoose.Schema;
 
 describe('discriminator docs', function () {
-  var Event;
-  var ClickedLinkEvent;
-  var SignedUpEvent;
-  var db;
+  let Event;
+  let ClickedLinkEvent;
+  let SignedUpEvent;
+  let db;
 
   before(function (done) {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
 
-    var eventSchema = new mongoose.Schema({time: Date});
+    const eventSchema = new mongoose.Schema({time: Date});
     Event = db.model('_event', eventSchema);
 
     ClickedLinkEvent = Event.discriminator('ClickedLink',
@@ -48,22 +48,22 @@ describe('discriminator docs', function () {
    * is the union of the base schema and the discriminator schema.
    */
   it('The `model.discriminator()` function', function (done) {
-    var options = {discriminatorKey: 'kind'};
+    const options = {discriminatorKey: 'kind'};
 
-    var eventSchema = new mongoose.Schema({time: Date}, options);
-    var Event = mongoose.model('Event', eventSchema);
+    const eventSchema = new mongoose.Schema({time: Date}, options);
+    const Event = mongoose.model('Event', eventSchema);
 
     // ClickedLinkEvent is a special type of Event that has
     // a URL.
-    var ClickedLinkEvent = Event.discriminator('ClickedLink',
+    const ClickedLinkEvent = Event.discriminator('ClickedLink',
       new mongoose.Schema({url: String}, options));
 
     // When you create a generic event, it can't have a URL field...
-    var genericEvent = new Event({time: Date.now(), url: 'google.com'});
+    const genericEvent = new Event({time: Date.now(), url: 'google.com'});
     assert.ok(!genericEvent.url);
 
     // But a ClickedLinkEvent can
-    var clickedEvent =
+    const clickedEvent =
       new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
     assert.ok(clickedEvent.url);
 
@@ -79,11 +79,11 @@ describe('discriminator docs', function () {
    * instances.
    */
   it('Discriminators save to the Event model\'s collection', function (done) {
-    var event1 = new Event({time: Date.now()});
-    var event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
-    var event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
+    const event1 = new Event({time: Date.now()});
+    const event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
+    const event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
 
-    var save = function (doc, callback) {
+    const save = function (doc, callback) {
       doc.save(function (error, doc) {
         callback(error, doc);
       });
@@ -107,9 +107,9 @@ describe('discriminator docs', function () {
    * this document is an instance of.
    */
   it('Discriminator keys', function (done) {
-    var event1 = new Event({time: Date.now()});
-    var event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
-    var event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
+    const event1 = new Event({time: Date.now()});
+    const event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
+    const event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
 
     assert.ok(!event1.__t);
     assert.equal(event2.__t, 'ClickedLink');
@@ -126,9 +126,9 @@ describe('discriminator docs', function () {
    * are smart enough to account for discriminators.
    */
   it('Discriminators add the discriminator key to queries', function (done) {
-    var event1 = new Event({time: Date.now()});
-    var event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
-    var event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
+    const event1 = new Event({time: Date.now()});
+    const event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
+    const event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
 
     Promise.all([event1.save(), event2.save(), event3.save()]).
       then(() => ClickedLinkEvent.find({})).
@@ -148,31 +148,31 @@ describe('discriminator docs', function () {
    * without affecting the base schema.
    */
   it('Discriminators copy pre and post hooks', function (done) {
-    var options = {discriminatorKey: 'kind'};
+    const options = {discriminatorKey: 'kind'};
 
-    var eventSchema = new mongoose.Schema({time: Date}, options);
-    var eventSchemaCalls = 0;
+    const eventSchema = new mongoose.Schema({time: Date}, options);
+    let eventSchemaCalls = 0;
     eventSchema.pre('validate', function (next) {
       ++eventSchemaCalls;
       next();
     });
-    var Event = mongoose.model('GenericEvent', eventSchema);
+    const Event = mongoose.model('GenericEvent', eventSchema);
 
-    var clickedLinkSchema = new mongoose.Schema({url: String}, options);
-    var clickedSchemaCalls = 0;
+    const clickedLinkSchema = new mongoose.Schema({url: String}, options);
+    let clickedSchemaCalls = 0;
     clickedLinkSchema.pre('validate', function (next) {
       ++clickedSchemaCalls;
       next();
     });
-    var ClickedLinkEvent = Event.discriminator('ClickedLinkEvent',
+    const ClickedLinkEvent = Event.discriminator('ClickedLinkEvent',
       clickedLinkSchema);
 
-    var event1 = new ClickedLinkEvent();
+    const event1 = new ClickedLinkEvent();
     event1.validate(function() {
       assert.equal(eventSchemaCalls, 1);
       assert.equal(clickedSchemaCalls, 1);
 
-      var generic = new Event();
+      const generic = new Event();
       generic.validate(function() {
         assert.equal(eventSchemaCalls, 2);
         assert.equal(clickedSchemaCalls, 1);
@@ -191,14 +191,14 @@ describe('discriminator docs', function () {
    * override the discriminator's _id field, as shown below.
    */
   it('Handling custom _id fields', function (done) {
-    var options = {discriminatorKey: 'kind'};
+    const options = {discriminatorKey: 'kind'};
 
     // Base schema has a custom String `_id` and a Date `time`...
-    var eventSchema = new mongoose.Schema({_id: String, time: Date},
+    const eventSchema = new mongoose.Schema({_id: String, time: Date},
       options);
-    var Event = mongoose.model('BaseEvent', eventSchema);
+    const Event = mongoose.model('BaseEvent', eventSchema);
 
-    var clickedLinkSchema = new mongoose.Schema({
+    const clickedLinkSchema = new mongoose.Schema({
       url: String,
       time: String
     }, options);
@@ -206,10 +206,10 @@ describe('discriminator docs', function () {
     // implicitly added ObjectId `_id`.
     assert.ok(clickedLinkSchema.path('_id'));
     assert.equal(clickedLinkSchema.path('_id').instance, 'ObjectID');
-    var ClickedLinkEvent = Event.discriminator('ChildEventBad',
+    const ClickedLinkEvent = Event.discriminator('ChildEventBad',
       clickedLinkSchema);
 
-    var event1 = new ClickedLinkEvent({_id: 'custom id', time: '4pm'});
+    const event1 = new ClickedLinkEvent({_id: 'custom id', time: '4pm'});
     // clickedLinkSchema overwrites the `time` path, but **not**
     // the `_id` path.
     assert.strictEqual(typeof event1._id, 'string');
@@ -225,19 +225,19 @@ describe('discriminator docs', function () {
    * the discriminator key for you.
    */
   it('Using discriminators with `Model.create()`', function(done) {
-    var Schema = mongoose.Schema;
-    var shapeSchema = new Schema({
+    const Schema = mongoose.Schema;
+    const shapeSchema = new Schema({
       name: String
     }, { discriminatorKey: 'kind' });
 
-    var Shape = db.model('Shape', shapeSchema);
+    const Shape = db.model('Shape', shapeSchema);
 
-    var Circle = Shape.discriminator('Circle',
+    const Circle = Shape.discriminator('Circle',
       new Schema({ radius: Number }));
-    var Square = Shape.discriminator('Square',
+    const Square = Shape.discriminator('Square',
       new Schema({ side: Number }));
 
-    var shapes = [
+    const shapes = [
       { name: 'Test' },
       { kind: 'Circle', radius: 5 },
       { kind: 'Square', side: 10 }
@@ -267,17 +267,17 @@ describe('discriminator docs', function () {
    * `post()` after calling `discriminator()`
    */
   it('Embedded discriminators in arrays', function(done) {
-    var eventSchema = new Schema({ message: String },
+    const eventSchema = new Schema({ message: String },
       { discriminatorKey: 'kind', _id: false });
 
-    var batchSchema = new Schema({ events: [eventSchema] });
+    const batchSchema = new Schema({ events: [eventSchema] });
 
     // `batchSchema.path('events')` gets the mongoose `DocumentArray`
-    var docArray = batchSchema.path('events');
+    const docArray = batchSchema.path('events');
 
     // The `events` array can contain 2 different types of events, a
     // 'clicked' event that requires an element id that was clicked...
-    var clickedSchema = new Schema({
+    const clickedSchema = new Schema({
       element: {
         type: String,
         required: true
@@ -285,20 +285,20 @@ describe('discriminator docs', function () {
     }, { _id: false });
     // Make sure to attach any hooks to `eventSchema` and `clickedSchema`
     // **before** calling `discriminator()`.
-    var Clicked = docArray.discriminator('Clicked', clickedSchema);
+    const Clicked = docArray.discriminator('Clicked', clickedSchema);
 
     // ... and a 'purchased' event that requires the product that was purchased.
-    var Purchased = docArray.discriminator('Purchased', new Schema({
+    const Purchased = docArray.discriminator('Purchased', new Schema({
       product: {
         type: String,
         required: true
       }
     }, { _id: false }));
 
-    var Batch = db.model('EventBatch', batchSchema);
+    const Batch = db.model('EventBatch', batchSchema);
 
     // Create a new batch of events with different kinds
-    var batch = {
+    const batch = {
       events: [
         { kind: 'Clicked', element: '#hero', message: 'hello' },
         { kind: 'Purchased', product: 'action-figure-1', message: 'world' }
@@ -339,23 +339,23 @@ describe('discriminator docs', function () {
    */
 
   it('Recursive embedded discriminators in arrays', function(done) {
-    var singleEventSchema = new Schema({ message: String },
+    const singleEventSchema = new Schema({ message: String },
       { discriminatorKey: 'kind', _id: false });
 
-    var eventListSchema = new Schema({ events: [singleEventSchema] });
+    const eventListSchema = new Schema({ events: [singleEventSchema] });
 
-    var subEventSchema = new Schema({
+    const subEventSchema = new Schema({
        sub_events: [singleEventSchema]
     }, { _id: false });
 
-    var SubEvent = subEventSchema.path('sub_events').
+    const SubEvent = subEventSchema.path('sub_events').
       discriminator('SubEvent', subEventSchema);
     eventListSchema.path('events').discriminator('SubEvent', subEventSchema);
 
-    var Eventlist = db.model('EventList', eventListSchema);
+    const Eventlist = db.model('EventList', eventListSchema);
 
     // Create a new batch of events with different kinds
-    var list = {
+    const list = {
       events: [
         { kind: 'SubEvent', sub_events: [{kind:'SubEvent', sub_events:[], message:'test1'}], message: 'hello' },
         { kind: 'SubEvent', sub_events: [{kind:'SubEvent', sub_events:[{kind:'SubEvent', sub_events:[], message:'test3'}], message:'test2'}], message: 'world' }
diff --git a/test/docs/promises.test.js b/test/docs/promises.test.js
index a6d82d04f80..c26b2a26e5e 100644
--- a/test/docs/promises.test.js
+++ b/test/docs/promises.test.js
@@ -1,11 +1,11 @@
 'use strict';
-var PromiseProvider = require('../../lib/promise_provider');
-var assert = require('assert');
-var mongoose = require('../../');
+const PromiseProvider = require('../../lib/promise_provider');
+const assert = require('assert');
+const mongoose = require('../../');
 
 describe('promises docs', function () {
-  var Band;
-  var db;
+  let Band;
+  let db;
 
   before(function (done) {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
@@ -33,12 +33,12 @@ describe('promises docs', function () {
    * You can also read more about [promises in Mongoose](https://masteringjs.io/tutorials/mongoose/promise).
    */
   it('Built-in Promises', function (done) {
-    var gnr = new Band({
+    const gnr = new Band({
       name: "Guns N' Roses",
       members: ['Axl', 'Slash']
     });
 
-    var promise = gnr.save();
+    const promise = gnr.save();
     assert.ok(promise instanceof Promise);
 
     promise.then(function (doc) {
@@ -56,11 +56,11 @@ describe('promises docs', function () {
    * a fully-fledged promise, use the `.exec()` function.
    */
   it('Queries are not promises', function (done) {
-    var query = Band.findOne({name: "Guns N' Roses"});
+    const query = Band.findOne({name: "Guns N' Roses"});
     assert.ok(!(query instanceof Promise));
 
     // acquit:ignore:start
-    var outstanding = 2;
+    let outstanding = 2;
     // acquit:ignore:end
 
     // A query is not a fully-fledged promise, but it does have a `.then()`.
@@ -73,7 +73,7 @@ describe('promises docs', function () {
     });
 
     // `.exec()` gives you a fully-fledged promise
-    var promise = query.exec();
+    const promise = query.exec();
     assert.ok(promise instanceof Promise);
 
     promise.then(function (doc) {
@@ -126,7 +126,7 @@ describe('promises docs', function () {
       return done();
     }
     // acquit:ignore:end
-    var query = Band.findOne({name: "Guns N' Roses"});
+    const query = Band.findOne({name: "Guns N' Roses"});
 
     // Use bluebird
     mongoose.Promise = require('bluebird');
diff --git a/test/docs/schemas.test.js b/test/docs/schemas.test.js
index 152c176c3b7..8ae5ed59866 100644
--- a/test/docs/schemas.test.js
+++ b/test/docs/schemas.test.js
@@ -1,11 +1,11 @@
 'use strict';
 
-var assert = require('assert');
-var mongoose = require('../../');
+const assert = require('assert');
+const mongoose = require('../../');
 
 describe('Advanced Schemas', function () {
-  var db;
-  var Schema = mongoose.Schema;
+  let db;
+  let Schema = mongoose.Schema;
 
   before(function() {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
@@ -52,7 +52,7 @@ describe('Advanced Schemas', function () {
     }
 
     schema.loadClass(PersonClass);
-    var Person = db.model('Person', schema);
+    const Person = db.model('Person', schema);
 
     Person.create({ firstName: 'Jon', lastName: 'Snow' }).
       then(doc => {
diff --git a/test/docs/schematypes.test.js b/test/docs/schematypes.test.js
index 5f994709834..77d32d9abf9 100644
--- a/test/docs/schematypes.test.js
+++ b/test/docs/schematypes.test.js
@@ -1,10 +1,10 @@
 'use strict';
-var assert = require('assert');
-var mongoose = require('../../');
+const assert = require('assert');
+const mongoose = require('../../');
 
 describe('schemaTypes', function () {
-  var db;
-  var Schema = mongoose.Schema;
+  let db;
+  let Schema = mongoose.Schema;
 
   before(function() {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
@@ -37,7 +37,7 @@ describe('schemaTypes', function () {
       // validate the provided `val` and throw a `CastError` if you
       // can't convert it.
       cast(val) {
-        var _val = Number(val);
+        let _val = Number(val);
         if (isNaN(_val)) {
           throw new Error('Int8: ' + val + ' is not a number');
         }
@@ -53,10 +53,10 @@ describe('schemaTypes', function () {
     // Don't forget to add `Int8` to the type registry
     mongoose.Schema.Types.Int8 = Int8;
 
-    var testSchema = new Schema({ test: Int8 });
-    var Test = mongoose.model('CustomTypeExample', testSchema);
+    const testSchema = new Schema({ test: Int8 });
+    const Test = mongoose.model('CustomTypeExample', testSchema);
 
-    var t = new Test();
+    const t = new Test();
     t.test = 'abc';
     assert.ok(t.validateSync());
     assert.equal(t.validateSync().errors['test'].name, 'CastError');
diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 451292f042a..f690a96cc73 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -1,12 +1,12 @@
 'use strict';
-var assert = require('assert');
-var mongoose = require('../../');
+const assert = require('assert');
+const mongoose = require('../../');
 
-var Promise = global.Promise || require('bluebird');
+const Promise = global.Promise || require('bluebird');
 
 describe('validation docs', function() {
-  var db;
-  var Schema = mongoose.Schema;
+  let db;
+  let Schema = mongoose.Schema;
 
   before(function() {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test', {
@@ -32,16 +32,16 @@ describe('validation docs', function() {
    */
 
   it('Validation', function(done) {
-    var schema = new Schema({
+    const schema = new Schema({
       name: {
         type: String,
         required: true
       }
     });
-    var Cat = db.model('Cat', schema);
+    const Cat = db.model('Cat', schema);
 
     // This cat has no name :(
-    var cat = new Cat();
+    const cat = new Cat();
     cat.save(function(error) {
       assert.equal(error.errors['name'].message,
         'Path `name` is required.');
@@ -66,7 +66,7 @@ describe('validation docs', function() {
    */
 
   it('Built-in Validators', function(done) {
-    var breakfastSchema = new Schema({
+    const breakfastSchema = new Schema({
       eggs: {
         type: Number,
         min: [6, 'Too few eggs'],
@@ -84,14 +84,14 @@ describe('validation docs', function() {
         }
       }
     });
-    var Breakfast = db.model('Breakfast', breakfastSchema);
+    const Breakfast = db.model('Breakfast', breakfastSchema);
 
-    var badBreakfast = new Breakfast({
+    const badBreakfast = new Breakfast({
       eggs: 2,
       bacon: 0,
       drink: 'Milk'
     });
-    var error = badBreakfast.validateSync();
+    let error = badBreakfast.validateSync();
     assert.equal(error.errors['eggs'].message,
       'Too few eggs');
     assert.ok(!error.errors['bacon']);
@@ -171,7 +171,7 @@ describe('validation docs', function() {
    * [`SchemaType#validate()` API docs](./api.html#schematype_SchemaType-validate).
    */
   it('Custom Validators', function(done) {
-    var userSchema = new Schema({
+    const userSchema = new Schema({
       phone: {
         type: String,
         validate: {
@@ -184,9 +184,9 @@ describe('validation docs', function() {
       }
     });
 
-    var User = db.model('user', userSchema);
-    var user = new User();
-    var error;
+    const User = db.model('user', userSchema);
+    const user = new User();
+    let error;
 
     user.phone = '555.0123';
     error = user.validateSync();
@@ -259,12 +259,12 @@ describe('validation docs', function() {
    */
 
   it('Validation Errors', function(done) {
-    var toySchema = new Schema({
+    const toySchema = new Schema({
       color: String,
       name: String
     });
 
-    var validator = function(value) {
+    const validator = function(value) {
       return /red|white|gold/i.test(value);
     };
     toySchema.path('color').validate(validator,
@@ -276,9 +276,9 @@ describe('validation docs', function() {
       return true;
     }, 'Name `{VALUE}` is not valid');
 
-    var Toy = db.model('Toy', toySchema);
+    const Toy = db.model('Toy', toySchema);
 
-    var toy = new Toy({ color: 'Green', name: 'Power Ranger' });
+    const toy = new Toy({ color: 'Green', name: 'Power Ranger' });
 
     toy.save(function (err) {
       // `err` is a ValidationError object
@@ -342,7 +342,7 @@ describe('validation docs', function() {
    */
 
   it('Required Validators On Nested Objects', function(done) {
-    var personSchema = new Schema({
+    let personSchema = new Schema({
       name: {
         first: String,
         last: String
@@ -355,7 +355,7 @@ describe('validation docs', function() {
     }, /Cannot.*'required'/);
 
     // To make a nested object required, use a single nested schema
-    var nameSchema = new Schema({
+    const nameSchema = new Schema({
       first: String,
       last: String
     });
@@ -367,10 +367,10 @@ describe('validation docs', function() {
       }
     });
 
-    var Person = db.model('Person', personSchema);
+    const Person = db.model('Person', personSchema);
 
-    var person = new Person();
-    var error = person.validateSync();
+    const person = new Person();
+    const error = person.validateSync();
     assert.ok(error.errors['name']);
     // acquit:ignore:start
     done();
@@ -392,18 +392,18 @@ describe('validation docs', function() {
    * caveats.
    */
   it('Update Validators', function(done) {
-    var toySchema = new Schema({
+    const toySchema = new Schema({
       color: String,
       name: String
     });
 
-    var Toy = db.model('Toys', toySchema);
+    const Toy = db.model('Toys', toySchema);
 
     Toy.schema.path('color').validate(function (value) {
       return /red|green|blue/i.test(value);
     }, 'Invalid color');
 
-    var opts = { runValidators: true };
+    const opts = { runValidators: true };
     Toy.updateOne({}, { color: 'not a color' }, opts, function (err) {
       assert.equal(err.errors.color.message,
         'Invalid color');
@@ -423,7 +423,7 @@ describe('validation docs', function() {
    */
 
   it('Update Validators and `this`', function(done) {
-    var toySchema = new Schema({
+    const toySchema = new Schema({
       color: String,
       name: String
     });
@@ -438,14 +438,14 @@ describe('validation docs', function() {
       return true;
     });
 
-    var Toy = db.model('ActionFigure', toySchema);
+    const Toy = db.model('ActionFigure', toySchema);
 
-    var toy = new Toy({ color: 'red', name: 'Red Power Ranger' });
-    var error = toy.validateSync();
+    const toy = new Toy({ color: 'red', name: 'Red Power Ranger' });
+    const error = toy.validateSync();
     assert.ok(error.errors['color']);
 
-    var update = { color: 'red', name: 'Red Power Ranger' };
-    var opts = { runValidators: true };
+    const update = { color: 'red', name: 'Red Power Ranger' };
+    const opts = { runValidators: true };
 
     Toy.updateOne({}, update, opts, function(error) {
       // The update validator throws an error:
@@ -466,7 +466,7 @@ describe('validation docs', function() {
 
   it('The `context` option', function(done) {
     // acquit:ignore:start
-    var toySchema = new Schema({
+    const toySchema = new Schema({
       color: String,
       name: String
     });
@@ -480,11 +480,11 @@ describe('validation docs', function() {
       return true;
     });
 
-    var Toy = db.model('Figure', toySchema);
+    const Toy = db.model('Figure', toySchema);
 
-    var update = { color: 'blue', name: 'Red Power Ranger' };
+    const update = { color: 'blue', name: 'Red Power Ranger' };
     // Note the context option
-    var opts = { runValidators: true, context: 'query' };
+    const opts = { runValidators: true, context: 'query' };
 
     Toy.updateOne({}, update, opts, function(error) {
       assert.ok(error.errors['color']);
@@ -506,17 +506,17 @@ describe('validation docs', function() {
 
   it('Update Validators Only Run On Updated Paths', function(done) {
     // acquit:ignore:start
-    var outstanding = 2;
+    let outstanding = 2;
     // acquit:ignore:end
-    var kittenSchema = new Schema({
+    const kittenSchema = new Schema({
       name: { type: String, required: true },
       age: Number
     });
 
-    var Kitten = db.model('Kitten', kittenSchema);
+    const Kitten = db.model('Kitten', kittenSchema);
 
-    var update = { color: 'blue' };
-    var opts = { runValidators: true };
+    const update = { color: 'blue' };
+    const opts = { runValidators: true };
     Kitten.updateOne({}, update, opts, function(err) {
       // Operation succeeds despite the fact that 'name' is not specified
       // acquit:ignore:start
@@ -524,7 +524,7 @@ describe('validation docs', function() {
       // acquit:ignore:end
     });
 
-    var unset = { $unset: { name: 1 } };
+    const unset = { $unset: { name: 1 } };
     Kitten.updateOne({}, unset, opts, function(err) {
       // Operation fails because 'name' is required
       assert.ok(err);
@@ -555,7 +555,7 @@ describe('validation docs', function() {
    */
 
   it('Update Validators Only Run For Some Operations', function(done) {
-    var testSchema = new Schema({
+    const testSchema = new Schema({
       number: { type: Number, max: 0 },
       arr: [{ message: { type: String, maxlength: 10 } }]
     });
@@ -566,10 +566,10 @@ describe('validation docs', function() {
       return v.length < 2;
     });
 
-    var Test = db.model('Test', testSchema);
+    const Test = db.model('Test', testSchema);
 
-    var update = { $inc: { number: 1 } };
-    var opts = { runValidators: true };
+    let update = { $inc: { number: 1 } };
+    const opts = { runValidators: true };
     Test.updateOne({}, update, opts, function(error) {
       // There will never be a validation error here
       update = { $push: [{ message: 'hello' }, { message: 'world' }] };
@@ -589,22 +589,22 @@ describe('validation docs', function() {
    */
 
   it('On $push and $addToSet', function(done) {
-    var testSchema = new Schema({
+    const testSchema = new Schema({
       numbers: [{ type: Number, max: 0 }],
       docs: [{
         name: { type: String, required: true }
       }]
     });
 
-    var Test = db.model('TestPush', testSchema);
+    const Test = db.model('TestPush', testSchema);
 
-    var update = {
+    const update = {
       $push: {
         numbers: 1,
         docs: { name: null }
       }
     };
-    var opts = { runValidators: true };
+    const opts = { runValidators: true };
     Test.updateOne({}, update, opts, function(error) {
       assert.ok(error.errors['numbers']);
       assert.ok(error.errors['docs']);
diff --git a/test/es-next/promises.test.es6.js b/test/es-next/promises.test.es6.js
index 4926c1f109e..f31d05aadd7 100644
--- a/test/es-next/promises.test.es6.js
+++ b/test/es-next/promises.test.es6.js
@@ -1,11 +1,11 @@
 'use strict';
-var PromiseProvider = require('../../lib/promise_provider');
-var assert = require('assert');
-var mongoose = require('../../');
+const PromiseProvider = require('../../lib/promise_provider');
+const assert = require('assert');
+const mongoose = require('../../');
 
 describe('promises docs', function () {
-  var Band;
-  var db;
+  let Band;
+  let db;
 
   before(function (done) {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
@@ -35,12 +35,12 @@ describe('promises docs', function () {
    * You can also read more about [promises in Mongoose](https://masteringjs.io/tutorials/mongoose/promise).
    */
   it('Built-in Promises', function (done) {
-    var gnr = new Band({
+    const gnr = new Band({
       name: "Guns N' Roses",
       members: ['Axl', 'Slash']
     });
 
-    var promise = gnr.save();
+    const promise = gnr.save();
     assert.ok(promise instanceof Promise);
 
     promise.then(function (doc) {
@@ -58,11 +58,11 @@ describe('promises docs', function () {
    * a fully-fledged promise, use the `.exec()` function.
    */
   it('Queries are not promises', function (done) {
-    var query = Band.findOne({name: "Guns N' Roses"});
+    const query = Band.findOne({name: "Guns N' Roses"});
     assert.ok(!(query instanceof Promise));
 
     // acquit:ignore:start
-    var outstanding = 2;
+    let outstanding = 2;
     // acquit:ignore:end
 
     // A query is not a fully-fledged promise, but it does have a `.then()`.
@@ -75,7 +75,7 @@ describe('promises docs', function () {
     });
 
     // `.exec()` gives you a fully-fledged promise
-    var promise = query.exec();
+    const promise = query.exec();
     assert.ok(promise instanceof Promise);
 
     promise.then(function (doc) {
@@ -166,7 +166,7 @@ describe('promises docs', function () {
       return done();
     }
     // acquit:ignore:end
-    var query = Band.findOne({name: "Guns N' Roses"});
+    const query = Band.findOne({name: "Guns N' Roses"});
 
     // Use bluebird
     mongoose.Promise = require('bluebird');
diff --git a/tools/auth.js b/tools/auth.js
index 967f5e1f8b9..7cfaf86c16a 100644
--- a/tools/auth.js
+++ b/tools/auth.js
@@ -6,7 +6,7 @@ const mongodb = require('mongodb');
 
 co(function*() {
   // Create new instance
-  var server = new Server('mongod', {
+  const server = new Server('mongod', {
     auth: null,
     dbpath: '/data/db/27017'
   });
diff --git a/tools/repl.js b/tools/repl.js
index ca3b6de5618..8139a512f7b 100644
--- a/tools/repl.js
+++ b/tools/repl.js
@@ -3,10 +3,10 @@
 const co = require('co');
 
 co(function*() {
-  var ReplSet = require('mongodb-topology-manager').ReplSet;
+  const ReplSet = require('mongodb-topology-manager').ReplSet;
 
   // Create new instance
-  var topology = new ReplSet('mongod', [{
+  const topology = new ReplSet('mongod', [{
     // mongod process options
     options: {
       bind_ip: 'localhost', port: 31000, dbpath: `/data/db/31000`
diff --git a/tools/sharded.js b/tools/sharded.js
index 82cad14162c..2b0cc04172e 100644
--- a/tools/sharded.js
+++ b/tools/sharded.js
@@ -3,10 +3,10 @@
 const co = require('co');
 
 co(function*() {
-  var Sharded = require('mongodb-topology-manager').Sharded;
+  const Sharded = require('mongodb-topology-manager').Sharded;
 
   // Create new instance
-  var topology = new Sharded({
+  const topology = new Sharded({
     mongod: 'mongod',
     mongos: 'mongos'
   });

From 7a6f5b474f06e9db32d1838a4eb6fa67b7fdcf2c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 13 Sep 2020 13:50:09 -0400
Subject: [PATCH 1209/2348] chore: add SaveOptions, more model properties re:
 #8108

---
 index.d.ts | 41 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 39 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 165097a60d6..8ed829fb547 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -29,8 +29,41 @@ declare module "mongoose" {
 
   class Document {}
 
-  class Model<T> extends Document {
-    constructor(obj?: any);
+  export var Model: Model<any>;
+  interface Model<T extends Document> {
+    new(doc?: any): T;
+
+    /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
+    save(options?: SaveOptions): Promise<this>;
+    save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
+    save(fn?: (err: Error | null, doc: this) => void): void;
+
+    /** Base Mongoose instance the model uses. */
+    base: typeof mongoose;
+
+    /**
+     * If this is a discriminator model, `baseModelName` is the name of
+     * the base model.
+     */
+    baseModelName: string | undefined;
+
+    /** Registered discriminators for this model. */
+    discriminators: { [name: string]: Model<any> } | undefined;
+
+    /** Translate any aliases fields/conditions so the final query or document object is pure */
+    translateAliases(raw: any): any;
+
+    remove(filter?: any, callback?: (err: Error | null) => void): Query<T>;
+  }
+
+  interface SaveOptions {
+    checkKeys?: boolean;
+    validateBeforeSave?: boolean;
+    validateModifiedOnly?: boolean;
+    timestamps?: boolean;
+    j?: boolean;
+    w?: number | string;
+    wtimeout?: number;
   }
 
   class Schema {
@@ -47,4 +80,8 @@ declare module "mongoose" {
   interface SchemaTypeOptions<T> {
     type?: T;
   }
+
+  interface Query<T extends Document> {
+    exec(callback?: (err: Error | null, res: T) => void): Promise<T>;
+  }
 }
\ No newline at end of file

From 1a4ddc83432a2c1ea33558974cb157f1d856fd3b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Sep 2020 19:01:12 -0400
Subject: [PATCH 1210/2348] docs(model+query): document using array of strings
 as projection

Fix #9413
---
 lib/model.js | 17 +++++++++++------
 lib/query.js |  5 ++++-
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 8b4b8e08974..5b823674d39 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2009,7 +2009,7 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
  *     await MyModel.find({ name: /john/i }, null, { skip: 10 }).exec();
  *
  * @param {Object|ObjectId} filter
- * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](http://mongoosejs.com/docs/api.html#query_Query-select)
+ * @param {Object|String|Array<String>} [projection] optional fields to return, see [`Query.prototype.select()`](http://mongoosejs.com/docs/api.html#query_Query-select)
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Function} [callback]
  * @return {Query}
@@ -2079,7 +2079,7 @@ Model.find = function find(conditions, projection, options, callback) {
  *     await Adventure.findById(id, 'name length').exec();
  *
  * @param {Any} id value of `_id` to query by
- * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
+ * @param {Object|String|Array<String>} [projection] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Function} [callback]
  * @return {Query}
@@ -2122,7 +2122,7 @@ Model.findById = function findById(id, projection, options, callback) {
  *     await Adventure.findOne({ country: 'Croatia' }, 'name length').exec();
  *
  * @param {Object} [conditions]
- * @param {Object|String} [projection] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
+ * @param {Object|String|Array<String>} [projection] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Function} [callback]
  * @return {Query}
@@ -2431,6 +2431,7 @@ Model.$where = function $where() {
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. An alternative to this would be using [Model.findOneAndReplace(conditions, update, options, callback)](https://mongoosejs.com/docs/api/model.html#model_Model.findOneAndReplace).
+ * @param {Object|String|Array<String>} [options.projection=null] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Function} [callback]
  * @return {Query}
  * @see Tutorial /docs/tutorials/findoneandupdate.html
@@ -2626,8 +2627,8 @@ Model.findByIdAndUpdate = function(id, update, options, callback) {
  *
  * - `sort`: if multiple docs are found by the conditions, sets the sort order to choose which doc to update
  * - `maxTimeMS`: puts a time limit on the query - requires mongodb >= 2.6.0
- * - `select`: sets the document fields to return
- * - `projection`: like select, it determines which fields to return, ex. `{ projection: { _id: 0 } }`
+ * - `select`: sets the document fields to return, ex. `{ projection: { _id: 0 } }`
+ * - `projection`: equivalent to `select`
  * - `rawResult`: if true, returns the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify)
  * - `strict`: overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict) for this update
  *
@@ -2660,6 +2661,7 @@ Model.findByIdAndUpdate = function(id, update, options, callback) {
  * @param {Object} conditions
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {Object|String|Array<String>} [options.projection=null] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Function} [callback]
  * @return {Query}
@@ -2772,6 +2774,7 @@ Model.findByIdAndDelete = function(id, options, callback) {
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
+ * @param {Object|String|Array<String>} [options.projection=null] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Function} [callback]
  * @return {Query}
  * @api public
@@ -2862,6 +2865,7 @@ Model.findOneAndReplace = function(filter, replacement, options, callback) {
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
+ * @param {Object|String|Array<String>} [options.projection=null] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Function} [callback]
  * @return {Query}
  * @see mongodb http://www.mongodb.org/display/DOCS/findAndModify+Command
@@ -2927,6 +2931,7 @@ Model.findOneAndRemove = function(conditions, options, callback) {
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {ClientSession} [options.session=null] The session associated with this query. See [transactions docs](/docs/transactions.html).
+ * @param {Object|String|Array<String>} [options.projection=null] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Function} [callback]
  * @return {Query}
  * @see Model.findOneAndRemove #model_Model.findOneAndRemove
@@ -3497,7 +3502,7 @@ Model.bulkWrite = function(ops, options, callback) {
  *     const mongooseCandy = Candy.hydrate({ _id: '54108337212ffb6d459f854c', type: 'jelly bean' });
  *
  * @param {Object} obj
- * @param {Object|String} [projection] optional projection containing which fields should be selected for this document
+ * @param {Object|String|Array<String>} [projection] optional projection containing which fields should be selected for this document
  * @return {Document} document instance
  * @api public
  */
diff --git a/lib/query.js b/lib/query.js
index 38b91c7d7b8..bb12be627e8 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -910,6 +910,9 @@ Query.prototype.projection = function(arg) {
  *
  *     // include a and b, exclude other fields
  *     query.select('a b');
+ *     // Equivalent syntaxes:
+ *     query.select(['a', 'b']);
+ *     query.select({ a: 1, b: 1 });
  *
  *     // exclude c and d, include other fields
  *     query.select('-c -d');
@@ -932,7 +935,7 @@ Query.prototype.projection = function(arg) {
  * @method select
  * @memberOf Query
  * @instance
- * @param {Object|String} arg
+ * @param {Object|String|Array<String>} arg
  * @return {Query} this
  * @see SchemaType
  * @api public

From 26027727578ac4b66abafe3d90b3cdbceb976d32 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Sep 2020 16:54:05 -0400
Subject: [PATCH 1211/2348] docs(faq+queries): add more detail about duplicate
 queries, including an faq entry

Fix #9386
---
 docs/faq.pug     | 25 +++++++++++++++++++++++++
 docs/queries.pug | 21 ++++++++++++++++++++-
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index 256de1a488a..37269ea197d 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -463,6 +463,31 @@ block content
     [perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in
     mind that populate() will execute a separate query for each document.
 
+    <hr id="duplicate-query" />
+
+    <a href="#duplicate-query">**Q**</a>. My query/update seems to execute twice. Why is this happening?
+
+    **A**. The most common cause of duplicate queries is **mixing callbacks and promises with queries**.
+    That's because passing a callback to a query function, like `find()` or `updateOne()`,
+    immediately executes the query, and calling [`then()`](https://masteringjs.io/tutorials/fundamentals/then)
+    executes the query again.
+
+    Mixing promises and callbacks can lead to duplicate entries in arrays.
+    For example, the below code inserts 2 entries into the `tags` array, **not* just 1.
+
+    ```javascript
+    const BlogPost = mongoose.model('BlogPost', new Schema({
+      title: String,
+      tags: [String]
+    }));
+
+    // Because there's both `await` **and** a callback, this `updateOne()` executes twice
+    // and thus pushes the same string into `tags` twice.
+    const update = { $push: { tags: ['javascript'] } };
+    await BlogPost.updateOne({ title: 'Introduction to Promises' }, update, (err, res) => {
+      console.log(res);
+    });
+    ```
 
     <hr id="add_something" />
 
diff --git a/docs/queries.pug b/docs/queries.pug
index 4a79b3a097f..82cf7600faf 100644
--- a/docs/queries.pug
+++ b/docs/queries.pug
@@ -154,7 +154,26 @@ block content
     ```
 
     Don't mix using callbacks and promises with queries, or you may end up
-    with duplicate operations.
+    with duplicate operations. That's because passing a callback to a query function
+    immediately executes the query, and calling [`then()`](https://masteringjs.io/tutorials/fundamentals/then)
+    executes the query again.
+
+    Mixing promises and callbacks can lead to duplicate entries in arrays.
+    For example, the below code inserts 2 entries into the `tags` array, **not* just 1.
+
+    ```javascript
+    const BlogPost = mongoose.model('BlogPost', new Schema({
+      title: String,
+      tags: [String]
+    }));
+
+    // Because there's both `await` **and** a callback, this `updateOne()` executes twice
+    // and thus pushes the same string into `tags` twice.
+    const update = { $push: { tags: ['javascript'] } };
+    await BlogPost.updateOne({ title: 'Introduction to Promises' }, update, (err, res) => {
+      console.log(res);
+    });
+    ```
 
     <h3 id="refs"><a href="#refs">References to other documents</a></h3>
 

From d2abbf8adaff13406a7e7c7b5545fd18dd60191a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Sep 2020 12:36:50 -0400
Subject: [PATCH 1212/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index c6113549740..b0f1bfcbeb4 100644
--- a/index.pug
+++ b/index.pug
@@ -364,6 +364,9 @@ html(lang='en')
               <a href="https://casino-academia.com/">
                 <img class="sponsor" src="https://images.opencollective.com/casinoacademia/90fc970/logo/256.png" style="height: 100px">
               </a>
+              <a href="https://nettikasinolista.com/">
+                <img class="sponsor" src="https://images.opencollective.com/nettikasinolista/fd361ee/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 82fb7089ba5f41f8737c17b219ff8a34c477f41f Mon Sep 17 00:00:00 2001
From: tphobe9312 <amar9312@gmail.com>
Date: Thu, 17 Sep 2020 21:36:48 +0530
Subject: [PATCH 1213/2348] `mongoose.model() --> mongoose.model()

MD link format fixed
---
 docs/middleware.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index 417175efeb2..c8c92b2c3f1 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -261,7 +261,7 @@ block content
     ```
 
     This means that you must add all middleware and [plugins](/docs/plugins.html)
-    **before** calling [`mongoose.model()](/docs/api/mongoose.html#mongoose_Mongoose-model).
+    **before** calling [mongoose.model()](/docs/api/mongoose.html#mongoose_Mongoose-model).
     The below script will print out "Hello from pre save":
 
     ```javascript

From e301787bde5b976365daf99d4d42f451af5f4ace Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Sep 2020 17:17:22 -0400
Subject: [PATCH 1214/2348] docs: quick fix

---
 docs/middleware.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index c8c92b2c3f1..0d09570584d 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -261,7 +261,7 @@ block content
     ```
 
     This means that you must add all middleware and [plugins](/docs/plugins.html)
-    **before** calling [mongoose.model()](/docs/api/mongoose.html#mongoose_Mongoose-model).
+    **before** calling [`mongoose.model()`](/docs/api/mongoose.html#mongoose_Mongoose-model).
     The below script will print out "Hello from pre save":
 
     ```javascript

From 7a86066f2e92ddd8cdd647e7ee4b479a2bc13378 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Sep 2020 18:23:41 -0400
Subject: [PATCH 1215/2348] test(model): repro #9418

---
 test/model.populate.test.js | 53 +++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 7600736d316..3d3d81145da 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9171,6 +9171,59 @@ describe('model: populate:', function() {
       assert.equal(docs[1]._id.toString(), p2._id.toString());
       assert.deepEqual(docs[0].children.map(c => c._id), [1]);
       assert.deepEqual(docs[1].children.map(c => c._id), [4]);
+
+      docs = yield Parent.find().sort({ _id: 1 }).
+        populate({ path: 'children', options: { perDocumentLimit: 1 } });
+      assert.equal(docs[0]._id.toString(), p._id.toString());
+      assert.equal(docs[1]._id.toString(), p2._id.toString());
+      assert.deepEqual(docs[0].children.map(c => c._id), [1]);
+      assert.deepEqual(docs[1].children.map(c => c._id), [4]);
+    });
+  });
+
+  it('perDocumentLimit as option to `populate()` method (gh-7318) (gh-9418)', function() {
+    const childSchema = Schema({ _id: Number, parentId: 'ObjectId' });
+
+    const parentSchema = Schema({ name: String });
+    parentSchema.virtual('children', {
+      ref: 'Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      justOne: false,
+      options: { sort: { _id: 1 } }
+    });
+
+    const Child = db.model('Child', childSchema);
+    const Parent = db.model('Parent', parentSchema);
+
+    return co(function*() {
+      const p = yield Parent.create({ name: 'test' });
+
+      yield Child.create([
+        { _id: 1, parentId: p._id },
+        { _id: 2, parentId: p._id },
+        { _id: 3, parentId: p._id }
+      ]);
+
+      const p2 = yield Parent.create({ name: 'test2' });
+      yield Child.create([
+        { _id: 4, parentId: p2._id },
+        { _id: 5, parentId: p2._id }
+      ]);
+
+      let docs = yield Parent.find().sort({ _id: 1 }).
+        populate({ path: 'children', perDocumentLimit: 1 });
+      assert.equal(docs[0]._id.toString(), p._id.toString());
+      assert.equal(docs[1]._id.toString(), p2._id.toString());
+      assert.deepEqual(docs[0].children.map(c => c._id), [1]);
+      assert.deepEqual(docs[1].children.map(c => c._id), [4]);
+
+      docs = yield Parent.find().sort({ _id: 1 }).
+        populate({ path: 'children', options: { perDocumentLimit: 1 } });
+      assert.equal(docs[0]._id.toString(), p._id.toString());
+      assert.equal(docs[1]._id.toString(), p2._id.toString());
+      assert.deepEqual(docs[0].children.map(c => c._id), [1]);
+      assert.deepEqual(docs[1].children.map(c => c._id), [4]);
     });
   });
 

From 014af7d2ddfda001a61ada18efe85dba0a44db93 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Sep 2020 18:23:52 -0400
Subject: [PATCH 1216/2348] fix(populate): handle `options.perDocumentLimit`
 option same as `perDocumentLimit` when calling `populate()`

Fix #9418
---
 lib/helpers/populate/getModelsMapForPopulate.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 2c50401c858..66baf19fa21 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -299,7 +299,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         ids = flat.filter((val, i) => modelNames[i] === modelName);
       }
 
-      if (!available[modelName] || currentOptions.perDocumentLimit != null) {
+      if (!available[modelName] || currentOptions.perDocumentLimit != null || get(currentOptions, 'options.perDocumentLimit') != null) {
         currentOptions = {
           model: Model
         };

From c83ad5f2207c73c86832fcc02b456ef2515fb4d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 18 Sep 2020 15:09:41 -0400
Subject: [PATCH 1217/2348] chore: release 5.10.6

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index ef2058858dc..6d3b37b197f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.10.6 / 2020-09-18
+===================
+ * fix(populate): handle `options.perDocumentLimit` option same as `perDocumentLimit` when calling `populate()` #9418
+ * fix(document): invalidate path if default function throws an error #9408
+ * fix: ensure subdocument defaults run after initial values are set when initing #9408
+ * docs(faq+queries): add more detail about duplicate queries, including an faq entry #9386
+ * docs: replace var with let and const in docs and test files #9414 [jmadankumar](https://github.com/jmadankumar)
+ * docs(model+query): document using array of strings as projection #9413
+ * docs(middleware): add missing backtick #9425 [tphobe9312](https://github.com/tphobe9312)
+
 5.10.5 / 2020-09-11
 ===================
  * fix: bump mongodb -> 3.6.2 #9411 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 8dcb335d3d6..584bb752845 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.5",
+  "version": "5.10.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 066cfa2b5fc27f8dd820b289ec5d1826d043f478 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 19 Sep 2020 16:04:05 -0400
Subject: [PATCH 1218/2348] chore: add generic schema type options re: #8108

---
 index.d.ts                       | 86 ++++++++++++++++++++++++++++++++
 lib/options/SchemaTypeOptions.js |  3 +-
 package.json                     |  6 ++-
 test/typescript/examples.test.ts | 42 ++++++++++++++++
 test/typescript/tsconfig.json    |  4 ++
 5 files changed, 137 insertions(+), 4 deletions(-)
 create mode 100644 test/typescript/examples.test.ts
 create mode 100644 test/typescript/tsconfig.json

diff --git a/index.d.ts b/index.d.ts
index 8ed829fb547..05ab0a46edd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2,6 +2,7 @@ declare module "mongoose" {
   import mongodb = require('mongodb');
   import mongoose = require('mongoose');
 
+  /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
   export function connect(uri: string, options: ConnectOptions, callback: (err: Error) => void): void;
   export function connect(uri: string, callback: (err: Error) => void): void;
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
@@ -79,6 +80,91 @@ declare module "mongoose" {
 
   interface SchemaTypeOptions<T> {
     type?: T;
+
+    /** Defines a virtual with the given name that gets/sets this path. */
+    alias?: string;
+
+    /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
+    validate?: RegExp | [RegExp, string] | Function;
+
+    /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
+    cast?: string;
+
+    /**
+     * If true, attach a required validator to this path, which ensures this path
+     * path cannot be set to a nullish value. If a function, Mongoose calls the
+     * function and only checks for nullish values if the function returns a truthy value.
+     */
+    required?: boolean | (() => boolean);
+
+    /**
+     * The default value for this path. If a function, Mongoose executes the function
+     * and uses the return value as the default.
+     */
+    default?: T | ((this: any, doc: any) => T);
+
+    /**
+     * The model that `populate()` should use if populating this path.
+     */
+    ref?: string | Model<any> | ((this: any, doc: any) => string | Model<any>);
+
+    /**
+     * Whether to include or exclude this path by default when loading documents
+     * using `find()`, `findOne()`, etc.
+     */
+    select?: boolean | number;
+
+    /**
+     * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
+     * build an index on this path when the model is compiled.
+     */
+    index?: boolean | number | IndexOptions;
+
+    /**
+     * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose
+     * will build a unique index on this path when the
+     * model is compiled. [The `unique` option is **not** a validator](/docs/validation.html#the-unique-option-is-not-a-validator).
+     */
+    unique?: boolean | number;
+
+    /**
+     * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
+     * disallow changes to this path once the document is saved to the database for the first time. Read more
+     * about [immutability in Mongoose here](http://thecodebarbarian.com/whats-new-in-mongoose-5-6-immutable-properties.html).
+     */
+    immutable?: boolean | ((this: any, doc: any) => boolean);
+
+    /**
+     * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
+     * build a sparse index on this path.
+     */
+    sparse?: boolean | number;
+
+    /**
+     * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose
+     * will build a text index on this path.
+     */
+    text?: boolean | number | any;
+
+    /**
+     * Define a transform function for this individual schema type.
+     * Only called when calling `toJSON()` or `toObject()`.
+     */
+    transform?: (this: any, val: T) => any;
+
+    /** defines a custom getter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty). */
+    get?: (value: T, schematype?: this) => any;
+
+    /** defines a custom setter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty). */
+    set?: (value: T, schematype?: this) => any;
+  }
+
+  interface IndexOptions {
+    background?: boolean,
+    expires?: number | string
+    sparse?: boolean,
+    type?: string,
+    unique?: boolean
   }
 
   interface Query<T extends Document> {
diff --git a/lib/options/SchemaTypeOptions.js b/lib/options/SchemaTypeOptions.js
index 5dc59951959..d9149bac029 100644
--- a/lib/options/SchemaTypeOptions.js
+++ b/lib/options/SchemaTypeOptions.js
@@ -134,8 +134,7 @@ Object.defineProperty(SchemaTypeOptions.prototype, 'select', opts);
 
 /**
  * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
- * build an index on this path when the model is
- * compiled.
+ * build an index on this path when the model is compiled.
  *
  * @api public
  * @property index
diff --git a/package.json b/package.json
index dcbdb75203e..a05df331637 100644
--- a/package.json
+++ b/package.json
@@ -19,6 +19,7 @@
   ],
   "license": "MIT",
   "dependencies": {
+    "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.1",
     "mongodb": "3.6.1",
@@ -28,8 +29,8 @@
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.2.1",
-    "sliced": "1.0.1",
-    "sift": "7.0.1"
+    "sift": "7.0.1",
+    "sliced": "1.0.1"
   },
   "devDependencies": {
     "@babel/core": "7.10.5",
@@ -60,6 +61,7 @@
     "pug": "2.0.3",
     "q": "1.5.1",
     "semver": "5.5.0",
+    "typescript": "4.x",
     "uuid": "2.0.3",
     "uuid-parse": "1.0.0",
     "validator": "10.8.0",
diff --git a/test/typescript/examples.test.ts b/test/typescript/examples.test.ts
new file mode 100644
index 00000000000..a47030bd09a
--- /dev/null
+++ b/test/typescript/examples.test.ts
@@ -0,0 +1,42 @@
+import { connect, Schema, model, Model } from 'mongoose';
+
+// Schema definitions
+
+function createBasicSchemaDefinition(): void {
+  const schema: Schema = new Schema({ name: { type: 'String' } });
+
+  interface ITest extends Model<ITest> {
+    name?: string;
+  }
+
+  const Test = model<ITest>('Test', schema);
+
+  const doc: ITest = new Test({ name: 'foo' });
+  doc.name = 'bar';
+}
+
+function schemaGettersSetters(): void {
+  const schema: Schema = new Schema({
+    name: {
+      type: 'String',
+      get: (v: string) => v.toUpperCase(),
+      set: (v: string) => v.toUpperCase(),
+      cast: 'Invalid name'
+    }
+  });
+}
+
+function schemaFunctionsUsingThis(): void {
+  const schema: Schema = new Schema({
+    firstName: { type: String },
+    email: {
+      type: String,
+      default: function() {
+        return this.firstName + '@gmail.com';
+      },
+      immutable: doc => {
+        return !!doc.firstName;
+      }
+    }
+  });
+}
\ No newline at end of file
diff --git a/test/typescript/tsconfig.json b/test/typescript/tsconfig.json
new file mode 100644
index 00000000000..91b7111e980
--- /dev/null
+++ b/test/typescript/tsconfig.json
@@ -0,0 +1,4 @@
+{
+  "allowSyntheticDefaultImports": true,
+  "esModuleInterop": true
+}
\ No newline at end of file

From fa56068e679733efff7ad0e9dc064614d8dcc2c7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 19 Sep 2020 16:24:30 -0400
Subject: [PATCH 1219/2348] docs(guide): fix typo

Fix #9432
---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 803d214dce4..c539e4fa883 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -1130,7 +1130,7 @@ block content
     });
     ```
 
-    If you set `useNconstestedStrict` to true, mongoose will use the child schema's
+    If you set `useNestedStrict` to true, mongoose will use the child schema's
     `strict` option for casting updates.
 
     ```javascript

From 1d269ed970fa82ad8e390eda4d80b959731fefd4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Sep 2020 23:53:17 +0200
Subject: [PATCH 1220/2348] test(document): repro #9433

---
 test/document.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index bd99c7902bd..28b981e74cd 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9395,4 +9395,26 @@ describe('document', function() {
 
     assert.equal(doc.subJob[0].shippingAt.valueOf(), date.valueOf());
   });
+
+  it('passes document as an argument for `required` function in schema definition (gh-9433)', function() {
+    let docFromValidation;
+
+    const userSchema = new Schema({
+      name: {
+        type: String,
+        required: (doc) => {
+          docFromValidation = doc;
+          return doc.age > 18;
+        }
+      },
+      age: Number
+    });
+
+    const User = db.model('User', userSchema);
+    const user = new User({ age: 26 });
+    const err = user.validateSync();
+    assert.ok(err);
+
+    assert.ok(docFromValidation === user);
+  });
 });

From 05fb9acea490b32b249c35a104b4c794ce6a85b4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Sep 2020 23:53:34 +0200
Subject: [PATCH 1221/2348] enhancement(document): pass do document to required
 validator

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index d617630fc86..6d5050c0d7e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2167,7 +2167,7 @@ function _evaluateRequiredFunctions(doc) {
     const p = doc.schema.path(path);
 
     if (p != null && typeof p.originalRequiredValue === 'function') {
-      doc.$__.cachedRequired[path] = p.originalRequiredValue.call(doc);
+      doc.$__.cachedRequired[path] = p.originalRequiredValue.call(doc, doc);
     }
   });
 }

From 8eaec11c946931b06e5d051ecc8bb58db6e7ee04 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Sep 2020 12:43:43 -0400
Subject: [PATCH 1222/2348] chore(index.d.ts): add remaining schematype options
 and test cases

Re: #8108
---
 index.d.ts                                    | 45 +++++++++++++++++++
 test/typescript/connectSyntax.ts              | 10 +++++
 .../typescript/createBasicSchemaDefinition.ts | 12 +++++
 test/typescript/examples.test.ts              | 42 -----------------
 test/typescript/main.test.js                  | 44 ++++++++++++++++++
 test/typescript/maps.ts                       | 32 +++++++++++++
 test/typescript/schemaGettersSetters.ts       | 22 +++++++++
 test/typescript/tsconfig.json                 |  4 --
 8 files changed, 165 insertions(+), 46 deletions(-)
 create mode 100644 test/typescript/connectSyntax.ts
 create mode 100644 test/typescript/createBasicSchemaDefinition.ts
 delete mode 100644 test/typescript/examples.test.ts
 create mode 100644 test/typescript/main.test.js
 create mode 100644 test/typescript/maps.ts
 create mode 100644 test/typescript/schemaGettersSetters.ts
 delete mode 100644 test/typescript/tsconfig.json

diff --git a/index.d.ts b/index.d.ts
index 05ab0a46edd..70b7a109d19 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -157,6 +157,51 @@ declare module "mongoose" {
 
     /** defines a custom setter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty). */
     set?: (value: T, schematype?: this) => any;
+
+    /** array of allowed values for this path. Allowed for strings, numbers, and arrays of strings */
+    enum?: Array<string | number>
+
+    /** The default [subtype](http://bsonspec.org/spec.html) associated with this buffer when it is stored in MongoDB. Only allowed for buffer paths */
+    subtype?: number
+
+    /** The minimum value allowed for this path. Only allowed for numbers and dates. */
+    min?: number | Date;
+
+    /** The maximum value allowed for this path. Only allowed for numbers and dates. */
+    max?: number | Date;
+
+    /** Defines a TTL index on this path. Only allowed for dates. */
+    expires?: Date;
+
+    /** If `true`, Mongoose will skip gathering indexes on subpaths. Only allowed for subdocuments and subdocument arrays. */
+    excludeIndexes?: boolean;
+
+    /** If set, overrides the child schema's `_id` option. Only allowed for subdocuments and subdocument arrays. */
+    _id?: boolean;
+
+    /** If set, specifies the type of this map's values. Mongoose will cast this map's values to the given type. */
+    of?: Function | SchemaTypeOptions<any>;
+
+    /** If true, uses Mongoose's default `_id` settings. Only allowed for ObjectIds */
+    auto?: boolean;
+
+    /** Attaches a validator that succeeds if the data string matches the given regular expression, and fails otherwise. */
+    match?: RegExp;
+
+    /** If truthy, Mongoose will add a custom setter that lowercases this string using JavaScript's built-in `String#toLowerCase()`. */
+    lowercase?: boolean;
+
+    /** If truthy, Mongoose will add a custom setter that removes leading and trailing whitespace using JavaScript's built-in `String#trim()`. */
+    trim?: boolean;
+
+    /** If truthy, Mongoose will add a custom setter that uppercases this string using JavaScript's built-in `String#toUpperCase()`. */
+    uppercase?: boolean;
+
+    /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at least the given number. */
+    minlength?: number;
+
+    /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at most the given number. */
+    maxlength?: number;
   }
 
   interface IndexOptions {
diff --git a/test/typescript/connectSyntax.ts b/test/typescript/connectSyntax.ts
new file mode 100644
index 00000000000..bac6d0d3f1a
--- /dev/null
+++ b/test/typescript/connectSyntax.ts
@@ -0,0 +1,10 @@
+import { connect } from 'mongoose';
+
+// Promise
+connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }).
+  then(mongoose => console.log(mongoose.connect));
+
+// Callback
+connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }, (err: Error) => {
+  console.log(err.stack);
+});
\ No newline at end of file
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
new file mode 100644
index 00000000000..73fed6b9402
--- /dev/null
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -0,0 +1,12 @@
+import { Schema, model, Model } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Model<ITest> {
+  name?: string;
+}
+
+const Test = model<ITest>('Test', schema);
+
+const doc: ITest = new Test({ name: 'foo' });
+doc.name = 'bar';
\ No newline at end of file
diff --git a/test/typescript/examples.test.ts b/test/typescript/examples.test.ts
deleted file mode 100644
index a47030bd09a..00000000000
--- a/test/typescript/examples.test.ts
+++ /dev/null
@@ -1,42 +0,0 @@
-import { connect, Schema, model, Model } from 'mongoose';
-
-// Schema definitions
-
-function createBasicSchemaDefinition(): void {
-  const schema: Schema = new Schema({ name: { type: 'String' } });
-
-  interface ITest extends Model<ITest> {
-    name?: string;
-  }
-
-  const Test = model<ITest>('Test', schema);
-
-  const doc: ITest = new Test({ name: 'foo' });
-  doc.name = 'bar';
-}
-
-function schemaGettersSetters(): void {
-  const schema: Schema = new Schema({
-    name: {
-      type: 'String',
-      get: (v: string) => v.toUpperCase(),
-      set: (v: string) => v.toUpperCase(),
-      cast: 'Invalid name'
-    }
-  });
-}
-
-function schemaFunctionsUsingThis(): void {
-  const schema: Schema = new Schema({
-    firstName: { type: String },
-    email: {
-      type: String,
-      default: function() {
-        return this.firstName + '@gmail.com';
-      },
-      immutable: doc => {
-        return !!doc.firstName;
-      }
-    }
-  });
-}
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
new file mode 100644
index 00000000000..f3244f1392a
--- /dev/null
+++ b/test/typescript/main.test.js
@@ -0,0 +1,44 @@
+'use strict';
+
+const assert = require('assert');
+const typescript = require('typescript');
+
+const tsconfig = {
+  allowSyntheticDefaultImports: true,
+  esModuleInterop: true,
+  outDir: `${__dirname}/dist`
+};
+
+describe('typescript syntax', function() {
+  this.timeout(5000);
+
+  it('create schema and model', function() {
+    const errors = runTest('createBasicSchemaDefinition.ts');
+    assert.equal(errors.length, 0);
+  });
+
+  it('connect syntax', function() {
+    const errors = runTest('connectSyntax.ts');
+    assert.equal(errors.length, 0);
+  });
+
+  it('reports error on invalid getter syntax', function() {
+    const errors = runTest('schemaGettersSetters.ts');
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.messageText.includes('incorrect: number'), errors[0].messageText.messageText);
+  });
+
+  it('handles maps', function() {
+    const errors = runTest('maps.ts');
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.includes('\'string\' is not assignable'), errors[0].messageText);
+  });
+});
+
+function runTest(file) {
+  const program = typescript.createProgram([`${__dirname}/${file}`], tsconfig);
+
+  let emitResult = program.emit();
+
+  return typescript.getPreEmitDiagnostics(program).concat(emitResult.diagnostics);
+}
\ No newline at end of file
diff --git a/test/typescript/maps.ts b/test/typescript/maps.ts
new file mode 100644
index 00000000000..12f1e4cd2f1
--- /dev/null
+++ b/test/typescript/maps.ts
@@ -0,0 +1,32 @@
+import { Schema, model, Model } from 'mongoose';
+
+const schema: Schema = new Schema({
+  map1: {
+    type: Map,
+    of: Number
+  },
+  map2: {
+    type: Map,
+    of: { type: String, enum: ['hello, world'] }
+  },
+  map3: {
+    type: Map,
+    of: {
+      type: Number,
+      max: 'not a number'
+    }
+  }
+});
+
+interface ITest extends Model<ITest> {
+  map1: Map<string, number>,
+  map2: Map<string, string>,
+  map3: Map<string, number>
+}
+
+const Test = model<ITest>('Test', schema);
+
+const doc: ITest = new Test({});
+
+doc.map1.set('answer', 42);
+doc.map1.get('answer');
\ No newline at end of file
diff --git a/test/typescript/schemaGettersSetters.ts b/test/typescript/schemaGettersSetters.ts
new file mode 100644
index 00000000000..8b6307633ba
--- /dev/null
+++ b/test/typescript/schemaGettersSetters.ts
@@ -0,0 +1,22 @@
+import { Schema } from 'mongoose';
+
+const schema: Schema = new Schema({
+  name: {
+    type: 'String',
+    get: (v: string) => v.toUpperCase(),
+    set: (v: string) => v.toUpperCase(),
+    cast: 'Invalid name',
+    enum: ['hello']
+  },
+  buffer: {
+    type: Buffer,
+    subtype: 4
+  }
+});
+
+const schema2: Schema = new Schema({
+  name: {
+    type: 'String',
+    get: { incorrect: 42 }
+  }
+});
\ No newline at end of file
diff --git a/test/typescript/tsconfig.json b/test/typescript/tsconfig.json
deleted file mode 100644
index 91b7111e980..00000000000
--- a/test/typescript/tsconfig.json
+++ /dev/null
@@ -1,4 +0,0 @@
-{
-  "allowSyntheticDefaultImports": true,
-  "esModuleInterop": true
-}
\ No newline at end of file

From 40d408e62ec9baa3251694f538bf3d89c7bbdc04 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Sep 2020 15:05:20 -0400
Subject: [PATCH 1223/2348] test(schema): repro #9426

---
 test/schema.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 912340efd56..cebd39a0b9f 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1981,6 +1981,18 @@ describe('schema', function() {
         assert.ok(clone.path('events').Constructor.discriminators['gh7954_Clicked']);
         assert.ok(clone.path('events').Constructor.discriminators['gh7954_Purchased']);
       });
+
+      it('uses Mongoose instance\'s Schema constructor (gh-9426)', function() {
+        const db = new mongoose.Mongoose();
+        db.Schema.prototype.localTest = function() {
+          return 42;
+        };
+        const test = new db.Schema({});
+        assert.equal(test.localTest(), 42);
+
+        const test2 = test.clone();
+        assert.equal(test2.localTest(), 42);
+      });
     });
 
     it('TTL index with timestamps (gh-5656)', function(done) {

From 2007bc74e474c8908b5fdac3d66354ca424ceb6a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Sep 2020 15:05:30 -0400
Subject: [PATCH 1224/2348] fix(schema): make `Schema#clone()` use parent
 Mongoose instance's Schema constructor

Fix #9426
---
 lib/schema.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index d820f5eaffe..17157b1b75b 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -294,7 +294,9 @@ Schema.prototype.tree;
  */
 
 Schema.prototype.clone = function() {
-  const s = new Schema({}, this._userProvidedOptions);
+  const Constructor = this.base == null ? Schema : this.base.Schema;
+
+  const s = new Constructor({}, this._userProvidedOptions);
   s.base = this.base;
   s.obj = this.obj;
   s.options = utils.clone(this.options);

From fee3af19c622b153bb8f4ddf663d41a2796f98ac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Sep 2020 15:26:56 -0400
Subject: [PATCH 1225/2348] test(timestamps): repro #9428

---
 test/timestamps.test.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index c916c2ebc45..dc91bc1eb59 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -395,4 +395,11 @@ describe('timestamps', function() {
       assert.ok(newDoc.nestedDoc.updatedAt > doc.nestedDoc.updatedAt);
     });
   });
+
+  it('works with property named "set" (gh-9428)', function() {
+    const schema = new Schema({ set: String }, { timestamps: true });
+    const Model = db.model('Test', schema);
+
+    return Model.create({ set: 'test' }).then(doc => assert.ok(doc.createdAt));
+  });
 });

From 9faa7305e3596a5dbae4f4823b6a9d503f1090dc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Sep 2020 15:27:19 -0400
Subject: [PATCH 1226/2348] fix(timestamps): allow using timestamps when schema
 has a property named 'set'

Fix #9428
---
 lib/schema.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 17157b1b75b..42111258d16 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -180,7 +180,7 @@ function aliasFields(schema, paths) {
       })(prop)).
       set((function(p) {
         return function(v) {
-          return this.set(p, v);
+          return this.$set(p, v);
         };
       })(prop));
   }
@@ -1216,7 +1216,7 @@ Schema.prototype.setupTimestamp = function(timestamps) {
     const auto_id = this._id && this._id.auto;
 
     if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.isSelected(createdAt)) {
-      this.set(createdAt, auto_id ? this._id.getTimestamp() : defaultTimestamp);
+      this.$set(createdAt, auto_id ? this._id.getTimestamp() : defaultTimestamp);
     }
 
     if (!skipUpdatedAt && updatedAt && (this.isNew || this.isModified())) {
@@ -1228,7 +1228,7 @@ Schema.prototype.setupTimestamp = function(timestamps) {
           ts = this._id.getTimestamp();
         }
       }
-      this.set(updatedAt, ts);
+      this.$set(updatedAt, ts);
     }
 
     next();
@@ -1239,10 +1239,10 @@ Schema.prototype.setupTimestamp = function(timestamps) {
       currentTime() :
       this.constructor.base.now();
     if (createdAt && !this.get(createdAt)) {
-      this.set(createdAt, ts);
+      this.$set(createdAt, ts);
     }
     if (updatedAt && !this.get(updatedAt)) {
-      this.set(updatedAt, ts);
+      this.$set(updatedAt, ts);
     }
     return this;
   };

From b532fc85b710d6cf281f74875bfeb3f926bccd07 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Sep 2020 21:29:47 -0400
Subject: [PATCH 1227/2348] chore(index.d.ts): subdocument support for schema
 defs re: #8108

---
 index.d.ts                      |  5 ++++-
 test/typescript/main.test.js    |  8 +++++++-
 test/typescript/subdocuments.ts | 28 ++++++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 2 deletions(-)
 create mode 100644 test/typescript/subdocuments.ts

diff --git a/index.d.ts b/index.d.ts
index 70b7a109d19..a59ec182984 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -72,10 +72,13 @@ declare module "mongoose" {
      * Create a new schema
      */
     constructor(definition?: SchemaDefinition);
+
+    /** Adds key path / schema type pairs to this schema. */
+    add(obj: SchemaDefinition | Schema, prefix?: string): this;
   }
 
   interface SchemaDefinition {
-    [path: string]: SchemaTypeOptions<any>
+    [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Array<Schema> | Array<SchemaTypeOptions<any>>;
   }
 
   interface SchemaTypeOptions<T> {
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index f3244f1392a..634dea3cd10 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -30,8 +30,14 @@ describe('typescript syntax', function() {
 
   it('handles maps', function() {
     const errors = runTest('maps.ts');
+    console.log(errors);
     assert.equal(errors.length, 1);
-    assert.ok(errors[0].messageText.includes('\'string\' is not assignable'), errors[0].messageText);
+    assert.ok(errors[0].messageText.messageText.includes('not assignable'), errors[0].messageText.messageText);
+  });
+
+  it('subdocuments', function() {
+    const errors = runTest('subdocuments.ts');
+    assert.equal(errors.length, 0);
   });
 });
 
diff --git a/test/typescript/subdocuments.ts b/test/typescript/subdocuments.ts
new file mode 100644
index 00000000000..8f329ec8e79
--- /dev/null
+++ b/test/typescript/subdocuments.ts
@@ -0,0 +1,28 @@
+import { Schema, model, Model } from 'mongoose';
+
+const childSchema: Schema = new Schema({ name: String });
+
+const schema: Schema = new Schema({
+  child1: childSchema,
+  child2: {
+    type: childSchema,
+    _id: false
+  },
+  docarr1: [childSchema],
+  docarr2: [{
+    type: childSchema,
+    _id: false
+  }],
+});
+
+interface ITest extends Model<ITest> {
+  child1: { name: String },
+  child2: { name: String }
+}
+
+const Test = model<ITest>('Test', schema);
+
+const doc: ITest = new Test({});
+
+doc.child1 = { name: 'test1' };
+doc.child2 = { name: 'test2' };
\ No newline at end of file

From a23f4d306b65f47a1c4c2df7d5670bdec28defeb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Sep 2020 10:44:55 -0400
Subject: [PATCH 1228/2348] refactor(timestamps): consolidate timestamps tests,
 move setupTimestamps() logic out of `schema`

Fix #9440
---
 lib/helpers/timestamps/setupTimestamps.js | 104 +++++
 lib/schema.js                             | 100 +----
 test/schema.test.js                       |  16 -
 test/schema.timestamps.test.js            | 486 ----------------------
 test/timestamps.test.js                   | 465 +++++++++++++++++++++
 5 files changed, 571 insertions(+), 600 deletions(-)
 create mode 100644 lib/helpers/timestamps/setupTimestamps.js
 delete mode 100644 test/schema.timestamps.test.js

diff --git a/lib/helpers/timestamps/setupTimestamps.js b/lib/helpers/timestamps/setupTimestamps.js
new file mode 100644
index 00000000000..752a565738c
--- /dev/null
+++ b/lib/helpers/timestamps/setupTimestamps.js
@@ -0,0 +1,104 @@
+'use strict';
+
+const applyTimestampsToChildren = require('../update/applyTimestampsToChildren');
+const applyTimestampsToUpdate = require('../update/applyTimestampsToUpdate');
+const get = require('../get');
+const handleTimestampOption = require('../schema/handleTimestampOption');
+const symbols = require('../../schema/symbols');
+
+module.exports = function setupTimestamps(schema, timestamps) {
+  const childHasTimestamp = schema.childSchemas.find(withTimestamp);
+
+  function withTimestamp(s) {
+    const ts = s.schema.options.timestamps;
+    return !!ts;
+  }
+
+  if (!timestamps && !childHasTimestamp) {
+    return;
+  }
+
+  const createdAt = handleTimestampOption(timestamps, 'createdAt');
+  const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+  const currentTime = timestamps != null && timestamps.hasOwnProperty('currentTime') ?
+    timestamps.currentTime :
+    null;
+  const schemaAdditions = {};
+
+  schema.$timestamps = { createdAt: createdAt, updatedAt: updatedAt };
+
+  if (updatedAt && !schema.paths[updatedAt]) {
+    schemaAdditions[updatedAt] = Date;
+  }
+
+  if (createdAt && !schema.paths[createdAt]) {
+    schemaAdditions[createdAt] = Date;
+  }
+
+  schema.add(schemaAdditions);
+
+  schema.pre('save', function(next) {
+    const timestampOption = get(this, '$__.saveOptions.timestamps');
+    if (timestampOption === false) {
+      return next();
+    }
+
+    const skipUpdatedAt = timestampOption != null && timestampOption.updatedAt === false;
+    const skipCreatedAt = timestampOption != null && timestampOption.createdAt === false;
+
+    const defaultTimestamp = currentTime != null ?
+      currentTime() :
+      (this.ownerDocument ? this.ownerDocument() : this).constructor.base.now();
+    const auto_id = this._id && this._id.auto;
+
+    if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.isSelected(createdAt)) {
+      this.$set(createdAt, auto_id ? this._id.getTimestamp() : defaultTimestamp);
+    }
+
+    if (!skipUpdatedAt && updatedAt && (this.isNew || this.isModified())) {
+      let ts = defaultTimestamp;
+      if (this.isNew) {
+        if (createdAt != null) {
+          ts = this.$__getValue(createdAt);
+        } else if (auto_id) {
+          ts = this._id.getTimestamp();
+        }
+      }
+      this.$set(updatedAt, ts);
+    }
+
+    next();
+  });
+
+  schema.methods.initializeTimestamps = function() {
+    const ts = currentTime != null ?
+      currentTime() :
+      this.constructor.base.now();
+    if (createdAt && !this.get(createdAt)) {
+      this.$set(createdAt, ts);
+    }
+    if (updatedAt && !this.get(updatedAt)) {
+      this.$set(updatedAt, ts);
+    }
+    return this;
+  };
+
+  _setTimestampsOnUpdate[symbols.builtInMiddleware] = true;
+
+  const opts = { query: true, model: false };
+  schema.pre('findOneAndUpdate', opts, _setTimestampsOnUpdate);
+  schema.pre('replaceOne', opts, _setTimestampsOnUpdate);
+  schema.pre('update', opts, _setTimestampsOnUpdate);
+  schema.pre('updateOne', opts, _setTimestampsOnUpdate);
+  schema.pre('updateMany', opts, _setTimestampsOnUpdate);
+
+  function _setTimestampsOnUpdate(next) {
+    const now = currentTime != null ?
+      currentTime() :
+      this.model.base.now();
+    applyTimestampsToUpdate(now, createdAt, updatedAt, this.getUpdate(),
+      this.options, this.schema);
+    applyTimestampsToChildren(now, this.getUpdate(), this.model.schema);
+    next();
+  }
+};
\ No newline at end of file
diff --git a/lib/schema.js b/lib/schema.js
index 42111258d16..02c54b7c1db 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -12,16 +12,13 @@ const SchemaTypeOptions = require('./options/SchemaTypeOptions');
 const VirtualOptions = require('./options/VirtualOptions');
 const VirtualType = require('./virtualtype');
 const addAutoId = require('./helpers/schema/addAutoId');
-const applyTimestampsToChildren = require('./helpers/update/applyTimestampsToChildren');
-const applyTimestampsToUpdate = require('./helpers/update/applyTimestampsToUpdate');
 const arrayParentSymbol = require('./helpers/symbols').arrayParentSymbol;
 const get = require('./helpers/get');
 const getIndexes = require('./helpers/schema/getIndexes');
-const handleTimestampOption = require('./helpers/schema/handleTimestampOption');
 const merge = require('./helpers/schema/merge');
 const mpath = require('mpath');
 const readPref = require('./driver').get().ReadPreference;
-const symbols = require('./schema/symbols');
+const setupTimestamps = require('./helpers/timestamps/setupTimestamps');
 const util = require('util');
 const utils = require('./utils');
 const validateRef = require('./helpers/populate/validateRef');
@@ -1171,100 +1168,7 @@ Schema.prototype.hasMixedParent = function(path) {
  * @api private
  */
 Schema.prototype.setupTimestamp = function(timestamps) {
-  const childHasTimestamp = this.childSchemas.find(withTimestamp);
-
-  function withTimestamp(s) {
-    const ts = s.schema.options.timestamps;
-    return !!ts;
-  }
-
-  if (!timestamps && !childHasTimestamp) {
-    return;
-  }
-
-  const createdAt = handleTimestampOption(timestamps, 'createdAt');
-  const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
-  const currentTime = timestamps != null && timestamps.hasOwnProperty('currentTime') ?
-    timestamps.currentTime :
-    null;
-  const schemaAdditions = {};
-
-  this.$timestamps = { createdAt: createdAt, updatedAt: updatedAt };
-
-  if (updatedAt && !this.paths[updatedAt]) {
-    schemaAdditions[updatedAt] = Date;
-  }
-
-  if (createdAt && !this.paths[createdAt]) {
-    schemaAdditions[createdAt] = Date;
-  }
-
-  this.add(schemaAdditions);
-
-  this.pre('save', function(next) {
-    const timestampOption = get(this, '$__.saveOptions.timestamps');
-    if (timestampOption === false) {
-      return next();
-    }
-
-    const skipUpdatedAt = timestampOption != null && timestampOption.updatedAt === false;
-    const skipCreatedAt = timestampOption != null && timestampOption.createdAt === false;
-
-    const defaultTimestamp = currentTime != null ?
-      currentTime() :
-      (this.ownerDocument ? this.ownerDocument() : this).constructor.base.now();
-    const auto_id = this._id && this._id.auto;
-
-    if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.isSelected(createdAt)) {
-      this.$set(createdAt, auto_id ? this._id.getTimestamp() : defaultTimestamp);
-    }
-
-    if (!skipUpdatedAt && updatedAt && (this.isNew || this.isModified())) {
-      let ts = defaultTimestamp;
-      if (this.isNew) {
-        if (createdAt != null) {
-          ts = this.$__getValue(createdAt);
-        } else if (auto_id) {
-          ts = this._id.getTimestamp();
-        }
-      }
-      this.$set(updatedAt, ts);
-    }
-
-    next();
-  });
-
-  this.methods.initializeTimestamps = function() {
-    const ts = currentTime != null ?
-      currentTime() :
-      this.constructor.base.now();
-    if (createdAt && !this.get(createdAt)) {
-      this.$set(createdAt, ts);
-    }
-    if (updatedAt && !this.get(updatedAt)) {
-      this.$set(updatedAt, ts);
-    }
-    return this;
-  };
-
-  _setTimestampsOnUpdate[symbols.builtInMiddleware] = true;
-
-  const opts = { query: true, model: false };
-  this.pre('findOneAndUpdate', opts, _setTimestampsOnUpdate);
-  this.pre('replaceOne', opts, _setTimestampsOnUpdate);
-  this.pre('update', opts, _setTimestampsOnUpdate);
-  this.pre('updateOne', opts, _setTimestampsOnUpdate);
-  this.pre('updateMany', opts, _setTimestampsOnUpdate);
-
-  function _setTimestampsOnUpdate(next) {
-    const now = currentTime != null ?
-      currentTime() :
-      this.model.base.now();
-    applyTimestampsToUpdate(now, createdAt, updatedAt, this.getUpdate(),
-      this.options, this.schema);
-    applyTimestampsToChildren(now, this.getUpdate(), this.model.schema);
-    next();
-  }
+  return setupTimestamps(this, timestamps);
 };
 
 /*!
diff --git a/test/schema.test.js b/test/schema.test.js
index cebd39a0b9f..3feb752fa88 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1995,22 +1995,6 @@ describe('schema', function() {
       });
     });
 
-    it('TTL index with timestamps (gh-5656)', function(done) {
-      const testSchema = new mongoose.Schema({
-        foo: String,
-        updatedAt: {
-          type: Date,
-          expires: '2h'
-        }
-      }, { timestamps: true });
-
-      const indexes = testSchema.indexes();
-      assert.deepEqual(indexes, [
-        [{ updatedAt: 1 }, { background: true, expireAfterSeconds: 7200 }]
-      ]);
-      done();
-    });
-
     it('childSchemas prop (gh-5695)', function(done) {
       const schema1 = new Schema({ name: String });
       const schema2 = new Schema({ test: String });
diff --git a/test/schema.timestamps.test.js b/test/schema.timestamps.test.js
deleted file mode 100644
index 17b9e74da54..00000000000
--- a/test/schema.timestamps.test.js
+++ /dev/null
@@ -1,486 +0,0 @@
-'use strict';
-
-/**
- * Test dependencies.
- */
-
-const start = require('./common');
-
-const assert = require('assert');
-const co = require('co');
-
-const mongoose = start.mongoose;
-const Schema = mongoose.Schema;
-
-describe('schema options.timestamps', function() {
-  let conn;
-
-  before(function() {
-    conn = start();
-  });
-
-  after(function(done) {
-    conn.close(done);
-  });
-
-  describe('create schema with options.timestamps', function() {
-    it('should have createdAt and updatedAt fields', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      }, {
-        timestamps: true
-      });
-
-      assert.ok(TestSchema.path('createdAt'));
-      assert.ok(TestSchema.path('updatedAt'));
-      done();
-    });
-
-    it('should have createdAt and updatedAt fields', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      });
-
-      TestSchema.set('timestamps', true);
-
-      assert.ok(TestSchema.path('createdAt'));
-      assert.ok(TestSchema.path('updatedAt'));
-      done();
-    });
-
-    it('should have created and updatedAt fields', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      }, {
-        timestamps: {
-          createdAt: 'created'
-        }
-      });
-
-      assert.ok(TestSchema.path('created'));
-      assert.ok(TestSchema.path('updatedAt'));
-      done();
-    });
-
-    it('should have created and updatedAt fields', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      });
-
-      TestSchema.set('timestamps', {
-        createdAt: 'created'
-      });
-
-      assert.ok(TestSchema.path('created'));
-      assert.ok(TestSchema.path('updatedAt'));
-      done();
-    });
-
-    it('should have created and updated fields', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      }, {
-        timestamps: {
-          createdAt: 'created',
-          updatedAt: 'updated'
-        }
-      });
-
-      assert.ok(TestSchema.path('created'));
-      assert.ok(TestSchema.path('updated'));
-      done();
-    });
-
-    it('should have just createdAt if updatedAt set to falsy', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      });
-
-      TestSchema.set('timestamps', {
-        updatedAt: false
-      });
-
-      assert.ok(TestSchema.path('createdAt'));
-      assert.ok(!TestSchema.path('updatedAt'));
-      done();
-    });
-
-    it('should have created and updated fields', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      });
-
-      TestSchema.set('timestamps', {
-        createdAt: 'created',
-        updatedAt: 'updated'
-      });
-
-      assert.ok(TestSchema.path('created'));
-      assert.ok(TestSchema.path('updated'));
-      done();
-    });
-
-    it('should not override createdAt when not selected (gh-4340)', function(done) {
-      const TestSchema = new Schema({
-        name: String
-      }, {
-        timestamps: true
-      });
-
-      conn.deleteModel(/Test/);
-      const Test = conn.model('Test', TestSchema);
-
-      Test.create({
-        name: 'hello'
-      }, function(err, doc) {
-        // Let’s save the dates to compare later.
-        const createdAt = doc.createdAt;
-        const updatedAt = doc.updatedAt;
-
-        assert.ok(doc.createdAt);
-
-        Test.findById(doc._id, { name: true }, function(err, doc) {
-          // The dates shouldn’t be selected here.
-          assert.ok(!doc.createdAt);
-          assert.ok(!doc.updatedAt);
-
-          doc.name = 'world';
-
-          doc.save(function(err, doc) {
-            // Let’s save the new updatedAt date as it should have changed.
-            const newUpdatedAt = doc.updatedAt;
-
-            assert.ok(!doc.createdAt);
-            assert.ok(doc.updatedAt);
-
-            Test.findById(doc._id, function(err, doc) {
-              // Let’s make sure that everything is working again by
-              // comparing the dates with the ones we saved.
-              assert.equal(doc.createdAt.valueOf(), createdAt.valueOf());
-              assert.notEqual(doc.updatedAt.valueOf(), updatedAt.valueOf());
-              assert.equal(doc.updatedAt.valueOf(), newUpdatedAt.valueOf());
-
-              done();
-            });
-          });
-        });
-      });
-    });
-  });
-
-  describe('auto update createdAt and updatedAt when create/save/update document', function() {
-    let CatSchema;
-    let Cat;
-
-    before(function() {
-      CatSchema = new Schema({
-        name: String,
-        hobby: String
-      }, { timestamps: true });
-      Cat = conn.model('Cat', CatSchema);
-      return Cat.deleteMany({}).then(() => Cat.create({ name: 'newcat' }));
-    });
-
-    it('should have fields when create', function(done) {
-      const cat = new Cat({ name: 'newcat' });
-      cat.save(function(err, doc) {
-        assert.ok(doc.createdAt);
-        assert.ok(doc.updatedAt);
-        assert.ok(doc.createdAt.getTime() === doc.updatedAt.getTime());
-        done();
-      });
-    });
-
-    it('should have fields when create with findOneAndUpdate', function(done) {
-      Cat.findOneAndUpdate({ name: 'notexistname' }, { $set: {} }, { upsert: true, new: true }, function(err, doc) {
-        assert.ok(doc.createdAt);
-        assert.ok(doc.updatedAt);
-        assert.ok(doc.createdAt.getTime() === doc.updatedAt.getTime());
-        done();
-      });
-    });
-
-    it('should change updatedAt when save', function(done) {
-      Cat.findOne({ name: 'newcat' }, function(err, doc) {
-        const old = doc.updatedAt;
-
-        doc.hobby = 'coding';
-
-        doc.save(function(err, doc) {
-          assert.ok(doc.updatedAt.getTime() > old.getTime());
-          done();
-        });
-      });
-    });
-
-    it('should not change updatedAt when save with no modifications', function(done) {
-      Cat.findOne({ name: 'newcat' }, function(err, doc) {
-        const old = doc.updatedAt;
-
-        doc.save(function(err, doc) {
-          assert.ok(doc.updatedAt.getTime() === old.getTime());
-          done();
-        });
-      });
-    });
-
-    it('can skip with timestamps: false (gh-7357)', function() {
-      return co(function*() {
-        const cat = yield Cat.findOne();
-
-        const old = cat.updatedAt;
-
-        yield cb => setTimeout(() => cb(), 10);
-
-        cat.hobby = 'fishing';
-
-        yield cat.save({ timestamps: false });
-
-        assert.strictEqual(cat.updatedAt, old);
-      });
-    });
-
-    it('should change updatedAt when findOneAndUpdate', function(done) {
-      Cat.create({ name: 'test123' }, function(err) {
-        assert.ifError(err);
-        Cat.findOne({ name: 'test123' }, function(err, doc) {
-          const old = doc.updatedAt;
-          Cat.findOneAndUpdate({ name: 'test123' }, { $set: { hobby: 'fish' } }, { new: true }, function(err, doc) {
-            assert.ok(doc.updatedAt.getTime() > old.getTime());
-            done();
-          });
-        });
-      });
-    });
-
-    it('insertMany with createdAt off (gh-6381)', function() {
-      const CatSchema = new Schema({
-        name: String,
-        createdAt: {
-          type: Date,
-          default: function() {
-            return new Date('2013-06-01');
-          }
-        }
-      },
-      {
-        timestamps: {
-          createdAt: false,
-          updatedAt: true
-        }
-      });
-
-      conn.deleteModel(/Test/);
-      const Cat = conn.model('Test', CatSchema);
-
-      const d = new Date('2011-06-01');
-
-      return co(function*() {
-        yield Cat.deleteMany({});
-        yield Cat.insertMany([{ name: 'a' }, { name: 'b', createdAt: d }]);
-
-        const cats = yield Cat.find().sort('name');
-
-        assert.equal(cats[0].createdAt.valueOf(), new Date('2013-06-01').valueOf());
-        assert.equal(cats[1].createdAt.valueOf(), new Date('2011-06-01').valueOf());
-      });
-    });
-
-    it('should have fields when update', function(done) {
-      Cat.findOne({ name: 'newcat' }, function(err, doc) {
-        const old = doc.updatedAt;
-        Cat.update({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
-          Cat.findOne({ name: 'newcat' }, function(err, doc) {
-            assert.ok(doc.updatedAt.getTime() > old.getTime());
-            done();
-          });
-        });
-      });
-    });
-
-    it('should change updatedAt when updateOne', function(done) {
-      Cat.findOne({ name: 'newcat' }, function(err, doc) {
-        const old = doc.updatedAt;
-        Cat.updateOne({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
-          Cat.findOne({ name: 'newcat' }, function(err, doc) {
-            assert.ok(doc.updatedAt.getTime() > old.getTime());
-            done();
-          });
-        });
-      });
-    });
-
-    it('should change updatedAt when updateMany', function(done) {
-      Cat.findOne({ name: 'newcat' }, function(err, doc) {
-        const old = doc.updatedAt;
-        Cat.updateMany({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
-          Cat.findOne({ name: 'newcat' }, function(err, doc) {
-            assert.ok(doc.updatedAt.getTime() > old.getTime());
-            done();
-          });
-        });
-      });
-    });
-
-    it('nested docs (gh-4049)', function(done) {
-      const GroupSchema = new Schema({
-        cats: [CatSchema]
-      });
-
-      conn.deleteModel(/Test/);
-      const Group = conn.model('Test', GroupSchema);
-      const now = Date.now();
-      Group.create({ cats: [{ name: 'Garfield' }] }, function(error, group) {
-        assert.ifError(error);
-        assert.ok(group.cats[0].createdAt);
-        assert.ok(group.cats[0].createdAt.getTime() >= now);
-        done();
-      });
-    });
-
-    it('nested docs with push (gh-4049)', function(done) {
-      const GroupSchema = new Schema({
-        cats: [CatSchema]
-      });
-
-      conn.deleteModel(/Test/);
-      const Group = conn.model('Test', GroupSchema);
-      const now = Date.now();
-      Group.create({ cats: [{ name: 'Garfield' }] }, function(error, group) {
-        assert.ifError(error);
-        group.cats.push({ name: 'Keanu' });
-        group.save(function(error) {
-          assert.ifError(error);
-          Group.findById(group._id, function(error, group) {
-            assert.ifError(error);
-            assert.ok(group.cats[1].createdAt);
-            assert.ok(group.cats[1].createdAt.getTime() > now);
-            done();
-          });
-        });
-      });
-    });
-
-    after(function() {
-      return Cat.deleteMany({});
-    });
-  });
-
-  it('timestamps with number types (gh-3957)', function() {
-    const schema = Schema({
-      createdAt: Number,
-      updatedAt: Number,
-      name: String
-    }, { timestamps: true });
-    conn.deleteModel(/Test/);
-    const Model = conn.model('Test', schema);
-    const start = Date.now();
-
-    return co(function*() {
-      const doc = yield Model.create({ name: 'test' });
-
-      assert.equal(typeof doc.createdAt, 'number');
-      assert.equal(typeof doc.updatedAt, 'number');
-      assert.ok(doc.createdAt >= start);
-      assert.ok(doc.updatedAt >= start);
-    });
-  });
-
-  it('timestamps with custom timestamp (gh-3957)', function() {
-    const schema = Schema({
-      createdAt: Number,
-      updatedAt: Number,
-      name: String
-    }, {
-      timestamps: { currentTime: () => 42 }
-    });
-    conn.deleteModel(/Test/);
-    const Model = conn.model('Test', schema);
-
-    return co(function*() {
-      const doc = yield Model.create({ name: 'test' });
-
-      assert.equal(typeof doc.createdAt, 'number');
-      assert.equal(typeof doc.updatedAt, 'number');
-      assert.equal(doc.createdAt, 42);
-      assert.equal(doc.updatedAt, 42);
-    });
-  });
-
-  it('shouldnt bump updatedAt in single nested subdocs that are not modified (gh-9357)', function() {
-    const nestedSchema = Schema({
-      nestedA: { type: String },
-      nestedB: { type: String }
-    }, { timestamps: true });
-    const parentSchema = Schema({
-      content: {
-        a: nestedSchema,
-        b: nestedSchema,
-        c: String
-      }
-    });
-
-    conn.deleteModel(/Test/);
-    const Parent = conn.model('Test', parentSchema);
-
-    return co(function*() {
-      yield Parent.deleteMany({});
-
-      yield Parent.create({
-        content: {
-          a: { nestedA: 'a' },
-          b: { nestedB: 'b' }
-        }
-      });
-
-      const doc = yield Parent.findOne();
-
-      const ts = doc.content.b.updatedAt;
-      doc.content.a.nestedA = 'b';
-      yield cb => setTimeout(cb, 10);
-      yield doc.save();
-
-      const fromDb = yield Parent.findById(doc);
-      assert.strictEqual(fromDb.content.b.updatedAt.valueOf(), ts.valueOf());
-    });
-  });
-
-  it('bumps updatedAt with mixed $set (gh-9357)', function() {
-    const nestedSchema = Schema({
-      nestedA: { type: String },
-      nestedB: { type: String }
-    }, { timestamps: true });
-    const parentSchema = Schema({
-      content: {
-        a: nestedSchema,
-        b: nestedSchema,
-        c: String
-      }
-    });
-
-    conn.deleteModel(/Test/);
-    const Parent = conn.model('Test', parentSchema);
-
-    return co(function*() {
-      yield Parent.deleteMany({});
-
-      const doc = yield Parent.create({
-        content: {
-          a: { nestedA: 'a' },
-          b: { nestedB: 'b' }
-        }
-      });
-      const ts = doc.content.b.updatedAt;
-
-      yield cb => setTimeout(cb, 10);
-      const fromDb = yield Parent.findOneAndUpdate({}, {
-        'content.c': 'value',
-        $set: {
-          'content.a.nestedA': 'value'
-        }
-      }, { new: true });
-
-      assert.ok(fromDb.content.a.updatedAt.valueOf() > ts.valueOf());
-    });
-  });
-});
diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index dc91bc1eb59..d37558cd3d2 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -23,6 +23,120 @@ describe('timestamps', function() {
   afterEach(() => require('./util').clearTestData(db));
   afterEach(() => require('./util').stopRemainingOps(db));
 
+  // These tests use schemas only, no database connection needed.
+  describe('schema options', function() {
+    it('should have createdAt and updatedAt fields', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      }, {
+        timestamps: true
+      });
+
+      assert.ok(TestSchema.path('createdAt'));
+      assert.ok(TestSchema.path('updatedAt'));
+      done();
+    });
+
+    it('should have createdAt and updatedAt fields', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      });
+
+      TestSchema.set('timestamps', true);
+
+      assert.ok(TestSchema.path('createdAt'));
+      assert.ok(TestSchema.path('updatedAt'));
+      done();
+    });
+
+    it('should have created and updatedAt fields', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      }, {
+        timestamps: {
+          createdAt: 'created'
+        }
+      });
+
+      assert.ok(TestSchema.path('created'));
+      assert.ok(TestSchema.path('updatedAt'));
+      done();
+    });
+
+    it('should have created and updatedAt fields', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      });
+
+      TestSchema.set('timestamps', {
+        createdAt: 'created'
+      });
+
+      assert.ok(TestSchema.path('created'));
+      assert.ok(TestSchema.path('updatedAt'));
+      done();
+    });
+
+    it('should have created and updated fields', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      }, {
+        timestamps: {
+          createdAt: 'created',
+          updatedAt: 'updated'
+        }
+      });
+
+      assert.ok(TestSchema.path('created'));
+      assert.ok(TestSchema.path('updated'));
+      done();
+    });
+
+    it('should have just createdAt if updatedAt set to falsy', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      });
+
+      TestSchema.set('timestamps', {
+        updatedAt: false
+      });
+
+      assert.ok(TestSchema.path('createdAt'));
+      assert.ok(!TestSchema.path('updatedAt'));
+      done();
+    });
+
+    it('should have created and updated fields', function(done) {
+      const TestSchema = new Schema({
+        name: String
+      });
+
+      TestSchema.set('timestamps', {
+        createdAt: 'created',
+        updatedAt: 'updated'
+      });
+
+      assert.ok(TestSchema.path('created'));
+      assert.ok(TestSchema.path('updated'));
+      done();
+    });
+
+    it('TTL index with timestamps (gh-5656)', function() {
+      const testSchema = new Schema({
+        foo: String,
+        updatedAt: {
+          type: Date,
+          expires: '2h'
+        }
+      }, { timestamps: true });
+
+      const indexes = testSchema.indexes();
+      assert.deepEqual(indexes, [
+        [{ updatedAt: 1 }, { background: true, expireAfterSeconds: 7200 }]
+      ]);
+    });
+  });
+
   it('does not override timestamp params defined in schema (gh-4868)', function(done) {
     const startTime = Date.now();
     const schema = new mongoose.Schema({
@@ -402,4 +516,355 @@ describe('timestamps', function() {
 
     return Model.create({ set: 'test' }).then(doc => assert.ok(doc.createdAt));
   });
+
+  it('should not override createdAt when not selected (gh-4340)', function(done) {
+    const TestSchema = new Schema({ name: String }, { timestamps: true });
+
+    const Test = db.model('Test', TestSchema);
+
+    Test.create({
+      name: 'hello'
+    }, function(err, doc) {
+      // Let’s save the dates to compare later.
+      const createdAt = doc.createdAt;
+      const updatedAt = doc.updatedAt;
+
+      assert.ok(doc.createdAt);
+
+      Test.findById(doc._id, { name: true }, function(err, doc) {
+        // The dates shouldn’t be selected here.
+        assert.ok(!doc.createdAt);
+        assert.ok(!doc.updatedAt);
+
+        doc.name = 'world';
+
+        doc.save(function(err, doc) {
+          // Let’s save the new updatedAt date as it should have changed.
+          const newUpdatedAt = doc.updatedAt;
+
+          assert.ok(!doc.createdAt);
+          assert.ok(doc.updatedAt);
+
+          Test.findById(doc._id, function(err, doc) {
+            // Let’s make sure that everything is working again by
+            // comparing the dates with the ones we saved.
+            assert.equal(doc.createdAt.valueOf(), createdAt.valueOf());
+            assert.notEqual(doc.updatedAt.valueOf(), updatedAt.valueOf());
+            assert.equal(doc.updatedAt.valueOf(), newUpdatedAt.valueOf());
+
+            done();
+          });
+        });
+      });
+    });
+  });
+
+  describe('auto update createdAt and updatedAt when create/save/update document', function() {
+    let CatSchema;
+    let Cat;
+
+    before(function() {
+      CatSchema = new Schema({
+        name: String,
+        hobby: String
+      }, { timestamps: true });
+      Cat = db.model('Cat', CatSchema);
+      return Cat.deleteMany({}).then(() => Cat.create({ name: 'newcat' }));
+    });
+
+    it('should have fields when create', function(done) {
+      const cat = new Cat({ name: 'newcat' });
+      cat.save(function(err, doc) {
+        assert.ok(doc.createdAt);
+        assert.ok(doc.updatedAt);
+        assert.ok(doc.createdAt.getTime() === doc.updatedAt.getTime());
+        done();
+      });
+    });
+
+    it('should have fields when create with findOneAndUpdate', function(done) {
+      Cat.findOneAndUpdate({ name: 'notexistname' }, { $set: {} }, { upsert: true, new: true }, function(err, doc) {
+        assert.ok(doc.createdAt);
+        assert.ok(doc.updatedAt);
+        assert.ok(doc.createdAt.getTime() === doc.updatedAt.getTime());
+        done();
+      });
+    });
+
+    it('should change updatedAt when save', function(done) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
+        const old = doc.updatedAt;
+
+        doc.hobby = 'coding';
+
+        doc.save(function(err, doc) {
+          assert.ok(doc.updatedAt.getTime() > old.getTime());
+          done();
+        });
+      });
+    });
+
+    it('should not change updatedAt when save with no modifications', function(done) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
+        const old = doc.updatedAt;
+
+        doc.save(function(err, doc) {
+          assert.ok(doc.updatedAt.getTime() === old.getTime());
+          done();
+        });
+      });
+    });
+
+    it('can skip with timestamps: false (gh-7357)', function() {
+      return co(function*() {
+        const cat = yield Cat.findOne();
+
+        const old = cat.updatedAt;
+
+        yield cb => setTimeout(() => cb(), 10);
+
+        cat.hobby = 'fishing';
+
+        yield cat.save({ timestamps: false });
+
+        assert.strictEqual(cat.updatedAt, old);
+      });
+    });
+
+    it('should change updatedAt when findOneAndUpdate', function(done) {
+      Cat.create({ name: 'test123' }, function(err) {
+        assert.ifError(err);
+        Cat.findOne({ name: 'test123' }, function(err, doc) {
+          const old = doc.updatedAt;
+          Cat.findOneAndUpdate({ name: 'test123' }, { $set: { hobby: 'fish' } }, { new: true }, function(err, doc) {
+            assert.ok(doc.updatedAt.getTime() > old.getTime());
+            done();
+          });
+        });
+      });
+    });
+
+    it('insertMany with createdAt off (gh-6381)', function() {
+      const CatSchema = new Schema({
+        name: String,
+        createdAt: {
+          type: Date,
+          default: function() {
+            return new Date('2013-06-01');
+          }
+        }
+      },
+      {
+        timestamps: {
+          createdAt: false,
+          updatedAt: true
+        }
+      });
+
+      const Cat = db.model('Test', CatSchema);
+
+      const d = new Date('2011-06-01');
+
+      return co(function*() {
+        yield Cat.deleteMany({});
+        yield Cat.insertMany([{ name: 'a' }, { name: 'b', createdAt: d }]);
+
+        const cats = yield Cat.find().sort('name');
+
+        assert.equal(cats[0].createdAt.valueOf(), new Date('2013-06-01').valueOf());
+        assert.equal(cats[1].createdAt.valueOf(), new Date('2011-06-01').valueOf());
+      });
+    });
+
+    it('should have fields when update', function(done) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
+        const old = doc.updatedAt;
+        Cat.update({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
+          Cat.findOne({ name: 'newcat' }, function(err, doc) {
+            assert.ok(doc.updatedAt.getTime() > old.getTime());
+            done();
+          });
+        });
+      });
+    });
+
+    it('should change updatedAt when updateOne', function(done) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
+        const old = doc.updatedAt;
+        Cat.updateOne({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
+          Cat.findOne({ name: 'newcat' }, function(err, doc) {
+            assert.ok(doc.updatedAt.getTime() > old.getTime());
+            done();
+          });
+        });
+      });
+    });
+
+    it('should change updatedAt when updateMany', function(done) {
+      Cat.findOne({ name: 'newcat' }, function(err, doc) {
+        const old = doc.updatedAt;
+        Cat.updateMany({ name: 'newcat' }, { $set: { hobby: 'fish' } }, function() {
+          Cat.findOne({ name: 'newcat' }, function(err, doc) {
+            assert.ok(doc.updatedAt.getTime() > old.getTime());
+            done();
+          });
+        });
+      });
+    });
+
+    it('nested docs (gh-4049)', function(done) {
+      const GroupSchema = new Schema({
+        cats: [CatSchema]
+      });
+
+      const Group = db.model('Test', GroupSchema);
+      const now = Date.now();
+      Group.create({ cats: [{ name: 'Garfield' }] }, function(error, group) {
+        assert.ifError(error);
+        assert.ok(group.cats[0].createdAt);
+        assert.ok(group.cats[0].createdAt.getTime() >= now);
+        done();
+      });
+    });
+
+    it('nested docs with push (gh-4049)', function(done) {
+      const GroupSchema = new Schema({
+        cats: [CatSchema]
+      });
+
+      const Group = db.model('Test', GroupSchema);
+      const now = Date.now();
+      Group.create({ cats: [{ name: 'Garfield' }] }, function(error, group) {
+        assert.ifError(error);
+        group.cats.push({ name: 'Keanu' });
+        group.save(function(error) {
+          assert.ifError(error);
+          Group.findById(group._id, function(error, group) {
+            assert.ifError(error);
+            assert.ok(group.cats[1].createdAt);
+            assert.ok(group.cats[1].createdAt.getTime() > now);
+            done();
+          });
+        });
+      });
+    });
+
+    after(function() {
+      return Cat.deleteMany({});
+    });
+  });
+
+  it('timestamps with number types (gh-3957)', function() {
+    const schema = Schema({
+      createdAt: Number,
+      updatedAt: Number,
+      name: String
+    }, { timestamps: true });
+    const Model = db.model('Test', schema);
+    const start = Date.now();
+
+    return co(function*() {
+      const doc = yield Model.create({ name: 'test' });
+
+      assert.equal(typeof doc.createdAt, 'number');
+      assert.equal(typeof doc.updatedAt, 'number');
+      assert.ok(doc.createdAt >= start);
+      assert.ok(doc.updatedAt >= start);
+    });
+  });
+
+  it('timestamps with custom timestamp (gh-3957)', function() {
+    const schema = Schema({
+      createdAt: Number,
+      updatedAt: Number,
+      name: String
+    }, {
+      timestamps: { currentTime: () => 42 }
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield Model.create({ name: 'test' });
+
+      assert.equal(typeof doc.createdAt, 'number');
+      assert.equal(typeof doc.updatedAt, 'number');
+      assert.equal(doc.createdAt, 42);
+      assert.equal(doc.updatedAt, 42);
+    });
+  });
+
+  it('shouldnt bump updatedAt in single nested subdocs that are not modified (gh-9357)', function() {
+    const nestedSchema = Schema({
+      nestedA: { type: String },
+      nestedB: { type: String }
+    }, { timestamps: true });
+    const parentSchema = Schema({
+      content: {
+        a: nestedSchema,
+        b: nestedSchema,
+        c: String
+      }
+    });
+
+    const Parent = db.model('Test', parentSchema);
+
+    return co(function*() {
+      yield Parent.deleteMany({});
+
+      yield Parent.create({
+        content: {
+          a: { nestedA: 'a' },
+          b: { nestedB: 'b' }
+        }
+      });
+
+      const doc = yield Parent.findOne();
+
+      const ts = doc.content.b.updatedAt;
+      doc.content.a.nestedA = 'b';
+      yield cb => setTimeout(cb, 10);
+      yield doc.save();
+
+      const fromDb = yield Parent.findById(doc);
+      assert.strictEqual(fromDb.content.b.updatedAt.valueOf(), ts.valueOf());
+    });
+  });
+
+  it('bumps updatedAt with mixed $set (gh-9357)', function() {
+    const nestedSchema = Schema({
+      nestedA: { type: String },
+      nestedB: { type: String }
+    }, { timestamps: true });
+    const parentSchema = Schema({
+      content: {
+        a: nestedSchema,
+        b: nestedSchema,
+        c: String
+      }
+    });
+
+    const Parent = db.model('Test', parentSchema);
+
+    return co(function*() {
+      yield Parent.deleteMany({});
+
+      const doc = yield Parent.create({
+        content: {
+          a: { nestedA: 'a' },
+          b: { nestedB: 'b' }
+        }
+      });
+      const ts = doc.content.b.updatedAt;
+
+      yield cb => setTimeout(cb, 10);
+      const fromDb = yield Parent.findOneAndUpdate({}, {
+        'content.c': 'value',
+        $set: {
+          'content.a.nestedA': 'value'
+        }
+      }, { new: true });
+
+      assert.ok(fromDb.content.a.updatedAt.valueOf() > ts.valueOf());
+    });
+  });
 });

From 1b2202d822534b9bfbf32b4a0ccf553855793b7a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Sep 2020 11:39:05 -0400
Subject: [PATCH 1229/2348] test(document): repro #9438

---
 test/document.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 28b981e74cd..4450453e83e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9417,4 +9417,23 @@ describe('document', function() {
 
     assert.ok(docFromValidation === user);
   });
+
+  it('works with path named isSelected (gh-9438)', function() {
+    const categorySchema = new Schema({
+      name: String,
+      categoryUrl: { type: String, required: true }, // Makes test fail
+      isSelected: Boolean
+    });
+
+    const siteSchema = new Schema({ categoryUrls: [categorySchema] });
+
+    const Test = db.model('Test', siteSchema);
+    const test = new Test({
+      categoryUrls: [
+        { name: 'A', categoryUrl: 'B', isSelected: false, isModified: false }
+      ]
+    });
+    const err = test.validateSync();
+    assert.ifError(err);
+  });
 });

From b128c9bf21b4d4edce09d39b0f9fbd5741f3e800 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Sep 2020 11:39:15 -0400
Subject: [PATCH 1230/2348] fix(document): handle required when schema has
 property named `isSelected`

Fix #9438
---
 lib/document.js        | 11 ++++++++++-
 lib/helpers/symbols.js |  3 +++
 lib/schematype.js      |  5 ++++-
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 6d5050c0d7e..8434d6f88a2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -41,6 +41,9 @@ const isMongooseObject = utils.isMongooseObject;
 const arrayAtomicsBackupSymbol = Symbol('mongoose.Array#atomicsBackup');
 const arrayAtomicsSymbol = require('./helpers/symbols').arrayAtomicsSymbol;
 const documentArrayParent = require('./helpers/symbols').documentArrayParent;
+const documentIsSelected = require('./helpers/symbols').documentIsSelected;
+const documentIsModified = require('./helpers/symbols').documentIsModified;
+const documentModifiedPaths = require('./helpers/symbols').documentModifiedPaths;
 const documentSchemaSymbol = require('./helpers/symbols').documentSchemaSymbol;
 const getSymbol = require('./helpers/symbols').getSymbol;
 const populateModelSymbol = require('./helpers/symbols').populateModelSymbol;
@@ -1844,6 +1847,8 @@ Document.prototype.modifiedPaths = function(options) {
   }, []);
 };
 
+Document.prototype[documentModifiedPaths] = Document.prototype.modifiedPaths;
+
 /**
  * Returns true if this document was modified, else false.
  *
@@ -1868,7 +1873,7 @@ Document.prototype.isModified = function(paths, modifiedPaths) {
     if (!Array.isArray(paths)) {
       paths = paths.split(' ');
     }
-    const modified = modifiedPaths || this.modifiedPaths();
+    const modified = modifiedPaths || this[documentModifiedPaths]();
     const directModifiedPaths = Object.keys(this.$__.activePaths.states.modify);
     const isModifiedChild = paths.some(function(path) {
       return !!~modified.indexOf(path);
@@ -1884,6 +1889,8 @@ Document.prototype.isModified = function(paths, modifiedPaths) {
   return this.$__.activePaths.some('modify');
 };
 
+Document.prototype[documentIsModified] = Document.prototype.isModified;
+
 /**
  * Checks if a path is set to its default.
  *
@@ -2040,6 +2047,8 @@ Document.prototype.isSelected = function isSelected(path) {
   return true;
 };
 
+Document.prototype[documentIsSelected] = Document.prototype.isSelected;
+
 /**
  * Checks if `path` was explicitly selected. If no projection, always returns
  * true.
diff --git a/lib/helpers/symbols.js b/lib/helpers/symbols.js
index ef0ddd573f2..9d619f774dc 100644
--- a/lib/helpers/symbols.js
+++ b/lib/helpers/symbols.js
@@ -5,6 +5,9 @@ exports.arrayParentSymbol = Symbol('mongoose#Array#_parent');
 exports.arrayPathSymbol = Symbol('mongoose#Array#_path');
 exports.arraySchemaSymbol = Symbol('mongoose#Array#_schema');
 exports.documentArrayParent = Symbol('mongoose:documentArrayParent');
+exports.documentIsSelected = Symbol('mongoose#Document#isSelected');
+exports.documentIsModified = Symbol('mongoose#Document#isModified');
+exports.documentModifiedPaths = Symbol('mongoose#Document#modifiedPaths');
 exports.documentSchemaSymbol = Symbol('mongoose#Document#schema');
 exports.getSymbol = Symbol('mongoose#Document#get');
 exports.modelSymbol = Symbol('mongoose#Model');
diff --git a/lib/schematype.js b/lib/schematype.js
index 6c3a29c9a89..af813753b18 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -16,6 +16,9 @@ const util = require('util');
 const utils = require('./utils');
 const validatorErrorSymbol = require('./helpers/symbols').validatorErrorSymbol;
 
+const documentIsSelected = require('./helpers/symbols').documentIsSelected;
+const documentIsModified = require('./helpers/symbols').documentIsModified;
+
 const CastError = MongooseError.CastError;
 const ValidatorError = MongooseError.ValidatorError;
 
@@ -915,7 +918,7 @@ SchemaType.prototype.required = function(required, message) {
     const cachedRequired = get(this, '$__.cachedRequired');
 
     // no validation when this path wasn't selected in the query.
-    if (cachedRequired != null && !this.isSelected(_this.path) && !this.isModified(_this.path)) {
+    if (cachedRequired != null && !this[documentIsSelected](_this.path) && !this[documentIsModified](_this.path)) {
       return true;
     }
 

From e540a13cef7160ca72d6588b5143c48ddd95c407 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Sep 2020 17:05:42 -0400
Subject: [PATCH 1231/2348] feat: basic queries re: #8108

---
 index.d.ts                   | 66 ++++++++++++++++++++++++++++++++++--
 test/typescript/main.test.js |  6 +++-
 test/typescript/queries.ts   | 16 +++++++++
 3 files changed, 84 insertions(+), 4 deletions(-)
 create mode 100644 test/typescript/queries.ts

diff --git a/index.d.ts b/index.d.ts
index a59ec182984..bcbf1e0a15c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -54,7 +54,47 @@ declare module "mongoose" {
     /** Translate any aliases fields/conditions so the final query or document object is pure */
     translateAliases(raw: any): any;
 
-    remove(filter?: any, callback?: (err: Error | null) => void): Query<T>;
+    /** Creates a `count` query: counts the number of documents that match `filter`. */
+    count(callback?: (err: any, count: number) => void): Query<number, T>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
+
+    /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
+    countDocuments(callback?: (err: any, count: number) => void): Query<number, T>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
+
+    /** Creates a `find` query: gets a list of documents that match `filter`. */
+    find(callback?: (err: any, count: number) => void): Query<Array<T>, T>;
+    find(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
+
+    remove(filter?: any, callback?: (err: Error | null) => void): Query<any, T>;
+  }
+
+  interface QueryOptions {
+    tailable?: number;
+    sort?: any;
+    limit?: number;
+    skip?: number;
+    maxscan?: number;
+    batchSize?: number;
+    comment?: any;
+    snapshot?: any;
+    readPreference?: mongodb.ReadPreferenceMode;
+    hint?: any;
+    upsert?: boolean;
+    writeConcern?: any;
+    timestamps?: boolean;
+    omitUndefined?: boolean;
+    overwriteDiscriminatorKey?: boolean;
+    lean?: boolean | any;
+    populate?: string;
+    projection?: any;
+    maxTimeMS?: number;
+    useFindAndModify?: boolean;
+    rawResult?: boolean;
+    collation?: mongodb.CollationDocument;
+    session?: mongodb.ClientSession;
+    explain?: any;
   }
 
   interface SaveOptions {
@@ -215,7 +255,27 @@ declare module "mongoose" {
     unique?: boolean
   }
 
-  interface Query<T extends Document> {
-    exec(callback?: (err: Error | null, res: T) => void): Promise<T>;
+  interface Query<T, DocType extends Document> {
+    exec(): Promise<T>;
+    exec(callback?: (err: Error | null, res: T) => void): void;
+
+    /** Specifies this query as a `count` query. */
+    count(callback?: (err: any, count: number) => void): Query<number, DocType>;
+    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
+
+    /** Specifies this query as a `countDocuments` query. */
+    countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType>;
+    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
   }
+
+  export type FilterQuery<T> = {
+    [P in keyof T]?: P extends '_id'
+      ? [Extract<T[P], mongodb.ObjectId>] extends [never]
+        ? mongodb.Condition<T[P]>
+        : mongodb.Condition<T[P] | string | { _id: mongodb.ObjectId }>
+      : [Extract<T[P], mongodb.ObjectId>] extends [never]
+      ? mongodb.Condition<T[P]>
+      : mongodb.Condition<T[P] | string>;
+  } &
+    mongodb.RootQuerySelector<T>;
 }
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 634dea3cd10..8ab3b5b2e70 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -30,7 +30,6 @@ describe('typescript syntax', function() {
 
   it('handles maps', function() {
     const errors = runTest('maps.ts');
-    console.log(errors);
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.messageText.includes('not assignable'), errors[0].messageText.messageText);
   });
@@ -39,6 +38,11 @@ describe('typescript syntax', function() {
     const errors = runTest('subdocuments.ts');
     assert.equal(errors.length, 0);
   });
+
+  it('queries', function() {
+    const errors = runTest('queries.ts');
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
new file mode 100644
index 00000000000..d48efdd5ca5
--- /dev/null
+++ b/test/typescript/queries.ts
@@ -0,0 +1,16 @@
+import { Schema, model, Model } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Model<ITest> {
+  name?: string;
+}
+
+const Test = model<ITest>('Test', schema);
+
+Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
+
+Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => console.log(res));
+
+Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().
+  then((res: Array<ITest>) => console.log(res[0].name));
\ No newline at end of file

From 2fc8af634b47162297472b0d8e0fb62ce3b4654a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Sep 2020 17:16:29 -0400
Subject: [PATCH 1232/2348] chore: add distinct and estimatedDocumentCount re:
 #8108

---
 index.d.ts                 | 12 ++++++++++++
 test/typescript/queries.ts |  4 +++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index bcbf1e0a15c..eb2a04a5241 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -62,6 +62,12 @@ declare module "mongoose" {
     countDocuments(callback?: (err: any, count: number) => void): Query<number, T>;
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
 
+    /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T>;
+
+    /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
+
     /** Creates a `find` query: gets a list of documents that match `filter`. */
     find(callback?: (err: any, count: number) => void): Query<Array<T>, T>;
     find(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
@@ -266,6 +272,12 @@ declare module "mongoose" {
     /** Specifies this query as a `countDocuments` query. */
     countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType>;
     countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
+
+    /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
+
+    /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T>;    
   }
 
   export type FilterQuery<T> = {
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index d48efdd5ca5..432c6f9eba2 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -13,4 +13,6 @@ Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
 Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => console.log(res));
 
 Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().
-  then((res: Array<ITest>) => console.log(res[0].name));
\ No newline at end of file
+  then((res: Array<ITest>) => console.log(res[0].name));
+
+Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
\ No newline at end of file

From 374a50bc7c64a049830dae7d999ec76240aaefbc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Sep 2020 12:15:34 -0400
Subject: [PATCH 1233/2348] chore(index.d.ts): add support for update methods,
 Types namespace

Re: #8108
---
 index.d.ts                 | 60 ++++++++++++++++++++++++++++++++++----
 test/typescript/queries.ts |  9 ++++--
 2 files changed, 62 insertions(+), 7 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index eb2a04a5241..cbfdde44b1a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -28,6 +28,10 @@ declare module "mongoose" {
     autoCreate?: boolean;
   }
 
+  namespace Types {
+    class ObjectId extends mongodb.ObjectID {}
+  }
+
   class Document {}
 
   export var Model: Model<any>;
@@ -39,6 +43,8 @@ declare module "mongoose" {
     save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
     save(fn?: (err: Error | null, doc: this) => void): void;
 
+    $where(argument: string | Function): Query<Array<T>, T>;
+
     /** Base Mongoose instance the model uses. */
     base: typeof mongoose;
 
@@ -73,7 +79,25 @@ declare module "mongoose" {
     find(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
     find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
 
+    /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
+    /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
+    /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
+    /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
+    /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
     remove(filter?: any, callback?: (err: Error | null) => void): Query<any, T>;
+
+    /** Creates a Query, applies the passed conditions, and returns the Query. */
+    where(path: string, val?: any): Query<Array<T>, T>;
   }
 
   interface QueryOptions {
@@ -261,9 +285,11 @@ declare module "mongoose" {
     unique?: boolean
   }
 
-  interface Query<T, DocType extends Document> {
-    exec(): Promise<T>;
-    exec(callback?: (err: Error | null, res: T) => void): void;
+  interface Query<ResultType, DocType extends Document> {
+    exec(): Promise<ResultType>;
+    exec(callback?: (err: Error | null, res: ResultType) => void): void;
+
+    $where(argument: string | Function): Query<Array<DocType>, DocType>;
 
     /** Specifies this query as a `count` query. */
     count(callback?: (err: any, count: number) => void): Query<number, DocType>;
@@ -274,10 +300,30 @@ declare module "mongoose" {
     countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
+    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T>;    
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType>;
+
+    /** Creates a `find` query: gets a list of documents that match `filter`. */
+    find(callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
+    find(filter: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
+
+    /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
+    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+
+    /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
+    findOneAndUpdate(conditions?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+
+    /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+
+    /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+
+    /** Creates a Query, applies the passed conditions, and returns the Query. */
+    where(path: string, val?: any): Query<Array<DocType>, DocType>;
   }
 
   export type FilterQuery<T> = {
@@ -290,4 +336,8 @@ declare module "mongoose" {
       : mongodb.Condition<T[P] | string>;
   } &
     mongodb.RootQuerySelector<T>;
+  
+  export type UpdateQuery<T> = mongodb.UpdateQuery<T> & mongodb.MatchKeysAndValues<T>;
+
+  export type DocumentDefinition<T> = Omit<T, Exclude<keyof Model<T>, '_id'>>
 }
\ No newline at end of file
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 432c6f9eba2..8042d772de7 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,8 +1,9 @@
-import { Schema, model, Model } from 'mongoose';
+import { Schema, model, Model, Types } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 interface ITest extends Model<ITest> {
+  _id?: Types.ObjectId,
   name?: string;
 }
 
@@ -15,4 +16,8 @@ Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => consol
 Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().
   then((res: Array<ITest>) => console.log(res[0].name));
 
-Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
\ No newline at end of file
+Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
+
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
+
+Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
\ No newline at end of file

From f9c733bae4237b0f2ae145e661efe598c7a4a13c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Sep 2020 15:28:10 -0400
Subject: [PATCH 1234/2348] chore(index.d.ts): add more model functions,
 including create() and insertMany() re: #8108

---
 index.d.ts                   | 71 ++++++++++++++++++++++++++++++++----
 test/typescript/create.ts    | 21 +++++++++++
 test/typescript/main.test.js |  6 +++
 3 files changed, 90 insertions(+), 8 deletions(-)
 create mode 100644 test/typescript/create.ts

diff --git a/index.d.ts b/index.d.ts
index cbfdde44b1a..c4d55172f7c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -38,13 +38,6 @@ declare module "mongoose" {
   interface Model<T extends Document> {
     new(doc?: any): T;
 
-    /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
-    save(options?: SaveOptions): Promise<this>;
-    save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
-    save(fn?: (err: Error | null, doc: this) => void): void;
-
-    $where(argument: string | Function): Query<Array<T>, T>;
-
     /** Base Mongoose instance the model uses. */
     base: typeof mongoose;
 
@@ -54,6 +47,47 @@ declare module "mongoose" {
      */
     baseModelName: string | undefined;
 
+    /**
+     * Sends multiple `insertOne`, `updateOne`, `updateMany`, `replaceOne`,
+     * `deleteOne`, and/or `deleteMany` operations to the MongoDB server in one
+     * command. This is faster than sending multiple independent operations (e.g.
+     * if you use `create()`) because with `bulkWrite()` there is only one round
+     * trip to MongoDB.
+     */
+    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: any, res: mongodb.BulkWriteOpResultObject) => void): void;
+    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions): Promise<mongodb.BulkWriteOpResultObject>;
+
+    /** Creates a new document or documents */
+    create(doc: T | DocumentDefinition<T>): Promise<T>;
+    create(docs: Array<T | DocumentDefinition<T>>, options?: SaveOptions): Promise<Array<T>>;
+    create(...docs: Array<T | DocumentDefinition<T>>): Promise<T>;
+    create(doc: T | DocumentDefinition<T>, callback: (err: Error | null, doc: T) => void): void;
+    create(docs: Array<T | DocumentDefinition<T>>, callback: (err: Error | null, docs: Array<T>) => void): void;
+
+    /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
+    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T | InsertManyResult>;
+    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T> | InsertManyResult>;
+    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions, callback?: (err: Error | null, res: T | InsertManyResult) => void): void;
+    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions, callback?: (err: Error | null, res: Array<T> | InsertManyResult) => void): void;
+
+    /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
+    save(options?: SaveOptions): Promise<this>;
+    save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
+    save(fn?: (err: Error | null, doc: this) => void): void;
+
+    /**
+     * Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
+     * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
+     * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
+     **/
+    startSession(options?: mongodb.SessionOptions, cb?: (err: any, session: mongodb.ClientSession) => void): Promise<mongodb.ClientSession>;
+
+    /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
+    watch(pipeline?: Array<object>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
+
+    /** Adds a `$where` clause to this query */
+    $where(argument: string | Function): Query<Array<T>, T>;
+
     /** Registered discriminators for this model. */
     discriminators: { [name: string]: Model<any> } | undefined;
 
@@ -82,12 +116,18 @@ declare module "mongoose" {
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
+    /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
+    /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
@@ -137,6 +177,18 @@ declare module "mongoose" {
     wtimeout?: number;
   }
 
+  interface InsertManyOptions {
+    limit?: number;
+    rawResult?: boolean;
+    ordered?: boolean;
+    lean?: boolean;
+    session?: mongodb.ClientSession;
+  }
+
+  interface InsertManyResult extends mongodb.InsertWriteOpResult<any> {
+    mongoose?: { validationErrors?: Array<Error> }
+  }
+
   class Schema {
     /**
      * Create a new schema
@@ -313,8 +365,11 @@ declare module "mongoose" {
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
+    /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
+    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(conditions?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
new file mode 100644
index 00000000000..a6cfd8eb456
--- /dev/null
+++ b/test/typescript/create.ts
@@ -0,0 +1,21 @@
+import { Schema, model, Model, Types } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Model<ITest> {
+  _id?: Types.ObjectId,
+  name?: string;
+}
+
+const Test = model<ITest>('Test', schema);
+
+Test.create({ name: 'test' }).then((doc: ITest) => console.log(doc.name));
+
+Test.create([{ name: 'test' }], { validateBeforeSave: false }).then((docs: ITest[]) => console.log(docs[0].name));
+
+Test.create({ name: 'test' }, { name: 'test2' }).then((doc: ITest) => console.log(doc.name));
+
+Test.insertMany({ name: 'test' }).then((doc: ITest) => console.log(doc.name));
+Test.insertMany([{ name: 'test' }], { session: null }).then((docs: ITest[]) => console.log(docs[0].name));
+
+Test.create({ name: 'test' }, { validateBeforeSave: true }).then((doc: ITest) => console.log(doc.name));
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 8ab3b5b2e70..a1f2f4e7dad 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -43,6 +43,12 @@ describe('typescript syntax', function() {
     const errors = runTest('queries.ts');
     assert.equal(errors.length, 0);
   });
+
+  it('create', function() {
+    const errors = runTest('create.ts');
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.messageText.includes('No overload matches'), errors[0].messageText.messageText);
+  });
 });
 
 function runTest(file) {

From a1506cb60f003c0409090ddf9ccb10de17a34a95 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Sep 2020 16:51:58 -0400
Subject: [PATCH 1235/2348] test(schema): repro #9429

---
 test/schema.test.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 3feb752fa88..33a86dcfea3 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2497,4 +2497,13 @@ describe('schema', function() {
     assert.equal(schematype.options.min, 4);
     assert.equal(schematype.options.get, get);
   });
+
+  it('applies correct schema to nested primitive arrays (gh-9429)', function() {
+    const schema = new Schema({
+      ids: [[{ type: 'ObjectId', required: true }]]
+    });
+
+    const casted = schema.path('ids').cast([[]]);
+    assert.equal(casted[0].$path(), 'ids.$');
+  });
 });

From 9cc9651eb150d6876981462c4aab8f5e8bfd28f0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Sep 2020 16:52:11 -0400
Subject: [PATCH 1236/2348] fix(schema): set correct path and schema on nested
 primitive arrays

Fix #9429
---
 lib/schema/array.js         | 4 ++--
 test/model.populate.test.js | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index a0bd356d4e2..044cc3af233 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -334,11 +334,11 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     }
 
     if (!(value && value.isMongooseArray)) {
-      value = new MongooseArray(value, this.path, doc);
+      value = new MongooseArray(value, this._arrayPath || this.path, doc);
     } else if (value && value.isMongooseArray) {
       // We need to create a new array, otherwise change tracking will
       // update the old doc (gh-4449)
-      value = new MongooseArray(value, this.path, doc);
+      value = new MongooseArray(value, this._arrayPath || this.path, doc);
     }
 
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 3d3d81145da..1e0e335e32f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8384,9 +8384,9 @@ describe('model: populate:', function() {
 
     return co(function*() {
       const c = yield Child.create({ name: 'test' });
-      yield Parent.create({ list: [{ fill: { child: c._id } }] });
+      const p = yield Parent.create({ list: [{ fill: { child: c._id } }] });
 
-      const doc = yield Parent.findOne().populate('list.fill.child');
+      const doc = yield Parent.findById(p).populate('list.fill.child');
 
       assert.equal(doc.list.length, 1);
       assert.strictEqual(doc.list[0].fill.child.name, 'test');

From a37dc2b800358f40eb580848aa4feac3cfaf71d4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Sep 2020 17:25:36 -0400
Subject: [PATCH 1237/2348] chore: release 5.10.7

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 6d3b37b197f..dbc18350d6a 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.10.7 / 2020-09-24
+===================
+ * fix(schema): set correct path and schema on nested primitive arrays #9429
+ * fix(document): pass document to required validator so `required` can use arrow functions #9435 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(document): handle required when schema has property named `isSelected` #9438
+ * fix(timestamps): allow using timestamps when schema has a property named 'set' #9428
+ * fix(schema): make `Schema#clone()` use parent Mongoose instance's Schema constructor #9426
+
 5.10.6 / 2020-09-18
 ===================
  * fix(populate): handle `options.perDocumentLimit` option same as `perDocumentLimit` when calling `populate()` #9418
diff --git a/package.json b/package.json
index 584bb752845..0160250c1d7 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.6",
+  "version": "5.10.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From e98340122dd8366033455bbe5da354da700b6849 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Sep 2020 14:15:22 -0400
Subject: [PATCH 1238/2348] chore: update opencollective sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index b0f1bfcbeb4..ddf019a783f 100644
--- a/index.pug
+++ b/index.pug
@@ -184,9 +184,6 @@ html(lang='en')
               <a href="https://icons8.com/">
                 <img class="sponsor" src="https://s3.amazonaws.com/codebarbarian-images/Icons8+Logo+500px.png" style="height:100px">
               </a>
-              <a href="https://topvet.net/">
-                <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Ftopvet.net&height=100" style="height:100px">
-              </a>
               <a href="https://www.embedgooglemap.net/blog/best-wordpress-themes/">
                 <img class="sponsor" title=" Best WordPress Themes " src="https://www.embedgooglemap.net/ultimate-wp-logo.png" style="height:100px">
               </a>
@@ -316,9 +313,6 @@ html(lang='en')
               <a href="https://casinohex.co.za/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-co-za/470843d/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://uk.edubirdie.com/">
-                <img class="sponsor" src="https://images.opencollective.com/uk-edubirdie-com/b1d51ab/logo/256.png" style="height: 100px">
-              </a>
               <a href="https://www.casinofever.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinofever-ca1/4ad150e/logo/256.png" style="height: 100px">
               </a>

From 523e6148590d7b52bac21f03f9db96e0da5e0a96 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Sep 2020 14:18:47 -0400
Subject: [PATCH 1239/2348] chore: add rel="sponsored" to opencollective links

---
 index.pug | 130 +++++++++++++++++++++++++++---------------------------
 1 file changed, 65 insertions(+), 65 deletions(-)

diff --git a/index.pug b/index.pug
index ddf019a783f..a7a7b39e731 100644
--- a/index.pug
+++ b/index.pug
@@ -166,199 +166,199 @@ html(lang='en')
 
           <div class="sponsors">
             <div>
-              <a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
+              <a rel="sponsored" href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/payment-ninja-mongoose.png" style="height: 100px">
               </a>
-              <a href="https://www.codefirst.co.uk/">
+              <a rel="sponsored" href="https://www.codefirst.co.uk/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fdde88120-e914-11e8-a662-278259d35390.png&height=100">
               </a>
-              <a href="https://www.dontpayfull.com/">
+              <a rel="sponsored" href="https://www.dontpayfull.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F84c4ba80-1955-11e8-8343-278614155b3e.png&height=100" style="height:100px">
               </a>
-              <a href="https://frontendmasters.com/">
+              <a rel="sponsored" href="https://frontendmasters.com/">
                 <img class="sponsor" src="https://images.opencollective.com/frontendmasters/0b9cda4/logo/256.png" style="height:100px">
               </a>
-              <a href="https://www.vpsserver.com/">
+              <a rel="sponsored" href="https://www.vpsserver.com/">
                 <img class="sponsor" src="https://pbs.twimg.com/profile_images/750300526538027008/jo7cFmU9_400x400.jpg" style="height: 100px">
               </a>
-              <a href="https://icons8.com/">
+              <a rel="sponsored" href="https://icons8.com/">
                 <img class="sponsor" src="https://s3.amazonaws.com/codebarbarian-images/Icons8+Logo+500px.png" style="height:100px">
               </a>
-              <a href="https://www.embedgooglemap.net/blog/best-wordpress-themes/">
+              <a rel="sponsored" href="https://www.embedgooglemap.net/blog/best-wordpress-themes/">
                 <img class="sponsor" title=" Best WordPress Themes " src="https://www.embedgooglemap.net/ultimate-wp-logo.png" style="height:100px">
               </a>
-              <a href="https://loanscouter.com/">
+              <a rel="sponsored" href="https://loanscouter.com/">
                 <img class="sponsor" src="https://images.opencollective.com/lead-supply/7400b71/logo.png" style="height: 100px">
               </a>
-              <a href="https://fair-laan.se/">
+              <a rel="sponsored" href="https://fair-laan.se/">
                 <img class="sponsor" src="https://images.opencollective.com/fair-laan-se/939304b/logo.png" style="height: 100px">
               </a>
-              <a href="https://craftresumes.com/professional-resume-writer/">
+              <a rel="sponsored" href="https://craftresumes.com/professional-resume-writer/">
                 <img class="sponsor" alt="Professional resume writer" src="https://s3.amazonaws.com/codebarbarian-images/craftresumes.png">
               </a>
-              <a href="https://uiuxagencies.top/">
+              <a rel="sponsored" href="https://uiuxagencies.top/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F62223ab0-f4f7-11e8-919f-53f2ea21a967.png&height=100" style="height:100px">
               </a>
-              <a href="https://www.vpnranks.com/">
+              <a rel="sponsored" href="https://www.vpnranks.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fvpnranks.com&height=100" style="height:100px">
               </a>
-              <a href="https://www.bestvpn.co/">
+              <a rel="sponsored" href="https://www.bestvpn.co/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fwww.bestvpn.co&height=100" style="height:100px">
               </a>
-              <a href="https://blokt.com/">
+              <a rel="sponsored" href="https://blokt.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fblokt.com&height=100" style="height:100px">
               </a>
-              <a href="http://clay.global/">
+              <a rel="sponsored" href="http://clay.global/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F09d57c90-637c-11e7-9ed2-bfa12b0351e8.jpg&height=100" style="height: 100px">
               </a>
-              <a href="https://tekhattan.com/">
+              <a rel="sponsored" href="https://tekhattan.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F31835450-5a98-11e9-adb1-e17fccd4c65e.png&height=80" style="height:80px">
               </a>
-              <a href="https://www.rabathelten.dk/">
+              <a rel="sponsored" href="https://www.rabathelten.dk/">
                 <img class="sponsor" src="/docs/images/dk.png" style="height: 100px">
               </a>
-              <a href="https://lemonlaw.site/">
+              <a rel="sponsored" href="https://lemonlaw.site/">
                 <img class="sponsor" src="https://images.opencollective.com/lemon-law/logo.png" style="height: 100px">
               </a>
-              <a href="https://uxplanet.org/top-ui-ux-design-agencies-user-experience-firms-8c54697e290">
+              <a rel="sponsored" href="https://uxplanet.org/top-ui-ux-design-agencies-user-experience-firms-8c54697e290">
                 <img class="sponsor" src="https://miro.medium.com/fit/c/160/160/1*A0FnBy5FBoVQC02SZXLXPg.png" style="height: 100px">
               </a>
-              <a href="https://proxybaylist.org/">
+              <a rel="sponsored" href="https://proxybaylist.org/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy-bay/e176fe4/avatar.png" style="height: 100px">
               </a>
-              <a href="https://ghostinspector.com/">
+              <a rel="sponsored" href="https://ghostinspector.com/">
                 <img class="sponsor" src="https://images.opencollective.com/ghostinspector/51b7be8/logo.png" style="height: 100px">
               </a>
-              <a href="https://wongagames.co.uk/">
+              <a rel="sponsored" href="https://wongagames.co.uk/">
                 <img class="sponsor" src="https://images.opencollective.com/wongagames/d3eb92f/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://medium.com/@niksundin/best-web-design-companies-1872e445775f">
+              <a rel="sponsored" href="https://medium.com/@niksundin/best-web-design-companies-1872e445775f">
                 <img class="sponsor" src="https://images.opencollective.com/top-web-design-agencies/d92d747/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.casinotop.com">
+              <a rel="sponsored" href="https://www.casinotop.com">
                 <img class="sponsor" src="https://images.opencollective.com/casinotop-com/10fd95b/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.casinotopp.net">
+              <a rel="sponsored" href="https://www.casinotopp.net">
                 <img class="sponsor" src="https://images.opencollective.com/casino-topp/1dd399a/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.bonus.ca/">
+              <a rel="sponsored" href="https://www.bonus.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/bonus-finder/4b3394e/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.bonus.net.nz/free-spins">
+              <a rel="sponsored" href="https://www.bonus.net.nz/free-spins">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-new-zealand/a5becb5/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.bonusfinder.com/casino">
+              <a rel="sponsored" href="https://www.bonusfinder.com/casino">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-com-us/8a47a19/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.bonus.com.de/freispiele">
+              <a rel="sponsored" href="https://www.bonus.com.de/freispiele">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-deutschland/646169e/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.minitool.com/">
+              <a rel="sponsored" href="https://www.minitool.com/">
                 <img class="sponsor" src="https://images.opencollective.com/minitool-solution-ltd/1519aa6/logo.png" style="height: 100px">
               </a>
-              <a href="https://maaltidskasser.net/">
+              <a rel="sponsored" href="https://maaltidskasser.net/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/maaltidskasser-logo.png" style="height: 100px" alt="Måltidskasser">
               </a>
-              <a href="https://taxfreesnus.com/">
+              <a rel="sponsored" href="https://taxfreesnus.com/">
                 <img class="sponsor" src="https://images.opencollective.com/taxfreesnus-com/ebf869a/logo.png" style="height: 100px">
               </a>
-              <a href="https://www.nettikasinot.org/">
+              <a rel="sponsored" href="https://www.nettikasinot.org/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-org/bbd887f/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.pelisivut.com/">
+              <a rel="sponsored" href="https://www.pelisivut.com/">
                 <img class="sponsor" src="https://images.opencollective.com/pelisivut/04f08f2/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.kasinot.fi/">
+              <a rel="sponsored" href="https://www.kasinot.fi/">
                 <img class="sponsor" src="https://images.opencollective.com/kasinot-fi/e09aa2e/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://mobilunity.com/">
+              <a rel="sponsored" href="https://mobilunity.com/">
                 <img class="sponsor" src="https://images.opencollective.com/mobilunity/e4ca372/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.paraskasino.fi/">
+              <a rel="sponsored" href="https://www.paraskasino.fi/">
                 <img class="sponsor" src="https://images.opencollective.com/paraskasino/a39c3d6/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinoonline.casino/">
+              <a rel="sponsored" href="https://casinoonline.casino/">
                 <img class="sponsor" src="https://images.opencollective.com/casino-online/4c8371c/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.casinot.net/">
+              <a rel="sponsored" href="https://www.casinot.net/">
                 <img class="sponsor" src="https://images.opencollective.com/casinot-net/242597a/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://420couponcodes.com/">
+              <a rel="sponsored" href="https://420couponcodes.com/">
                 <img class="sponsor" src="https://images.opencollective.com/420couponcodes/8965926/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.kasinohai.com/nettikasinot">
+              <a rel="sponsored" href="https://www.kasinohai.com/nettikasinot">
                 <img class="sponsor" src="https://images.opencollective.com/kasinohai-com/41d4f51/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://onlinecasinoinformatie.com/">
+              <a rel="sponsored" href="https://onlinecasinoinformatie.com/">
                 <img class="sponsor" src="https://images.opencollective.com/ricardo-goncalves/3275f75/avatar/256.png" style="height: 100px">
               </a>
-              <a href="https://onlinecasinoplatz.com/">
+              <a rel="sponsored" href="https://onlinecasinoplatz.com/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinoplatz-com/8f8b647/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
+              <a rel="sponsored" href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
                 <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinomatcher.com/ca/">
+              <a rel="sponsored" href="https://casinomatcher.com/ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinomatcher-com/31fbd0d/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://netticasinohex.com/kasinot/">
+              <a rel="sponsored" href="https://netticasinohex.com/kasinot/">
                 <img class="sponsor" src="https://images.opencollective.com/netticasinohex-com/71d7417/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinohex.at/online-casinos/">
+              <a rel="sponsored" href="https://casinohex.at/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-at/8e06f0e/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinohex.se/online-casinon/">
+              <a rel="sponsored" href="https://casinohex.se/online-casinon/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-se/795919b/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinohex.co.za/online-casinos/">
+              <a rel="sponsored" href="https://casinohex.co.za/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-co-za/470843d/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.casinofever.ca/">
+              <a rel="sponsored" href="https://www.casinofever.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinofever-ca1/4ad150e/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.parhaatnettikasinot.com/">
+              <a rel="sponsored" href="https://www.parhaatnettikasinot.com/">
                 <img class="sponsor" src="https://images.opencollective.com/parhaatnettikasinot-com/fc53017/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://swisscasinohex.com/online-casinos/">
+              <a rel="sponsored" href="https://swisscasinohex.com/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/swisscasinohex-com/107940c/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://onlinecasinohex.nl/online-casinos/nederland/">
+              <a rel="sponsored" href="https://onlinecasinohex.nl/online-casinos/nederland/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinohex-nl/ed24082/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://kasynohex.com/kasyna-online/">
+              <a rel="sponsored" href="https://kasynohex.com/kasyna-online/">
                 <img class="sponsor" src="https://images.opencollective.com/kasynohex-com/b25daf6/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinohex.ro/online-cazino/">
+              <a rel="sponsored" href="https://casinohex.ro/online-cazino/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-ro/493996e/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://norskcasinohex.com/casino-pa-nett/">
+              <a rel="sponsored" href="https://norskcasinohex.com/casino-pa-nett/">
                 <img class="sponsor" src="https://images.opencollective.com/norskcasinohex-com/f0d4c76/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://aussiecasinohex.com/online-casinos/">
+              <a rel="sponsored" href="https://aussiecasinohex.com/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/aussiecasinohex/923df37/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.japanesecasino.com/">
+              <a rel="sponsored" href="https://www.japanesecasino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/japanesecasino/b0ffe3c/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.parhaatkasinot.com/">
+              <a rel="sponsored" href="https://www.parhaatkasinot.com/">
                 <img class="sponsor" src="https://images.opencollective.com/parhaatkasinot/e7fda21/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.polskiekasyno.com/">
+              <a rel="sponsored" href="https://www.polskiekasyno.com/">
                 <img class="sponsor" src="https://images.opencollective.com/polskiekasyno-com/a8975c6/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casinohex.in/online-casinos/">
+              <a rel="sponsored" href="https://casinohex.in/online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casinohex-in/0d7625b/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://www.baocasino.com/">
+              <a rel="sponsored" href="https://www.baocasino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/baocasino/b5a71c4/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://onlinecasinoguide.co.nz/">
+              <a rel="sponsored" href="https://onlinecasinoguide.co.nz/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinoguide-co-nz/b16a388/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://casino-academia.com/">
+              <a rel="sponsored" href="https://casino-academia.com/">
                 <img class="sponsor" src="https://images.opencollective.com/casinoacademia/90fc970/logo/256.png" style="height: 100px">
               </a>
-              <a href="https://nettikasinolista.com/">
+              <a rel="sponsored" href="https://nettikasinolista.com/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinolista/fd361ee/logo/256.png" style="height: 100px">
               </a>
             </div>

From e167926a4e87258147fb86f91fba39129485f0e2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Sep 2020 17:38:29 -0400
Subject: [PATCH 1240/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index a7a7b39e731..790f1e2e2b1 100644
--- a/index.pug
+++ b/index.pug
@@ -361,6 +361,9 @@ html(lang='en')
               <a rel="sponsored" href="https://nettikasinolista.com/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinolista/fd361ee/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://casinopro.ca/">
+                <img class="sponsor" src="https://images.opencollective.com/casinopro/4729b46/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From c0318984bd285fee38f25c6b1e919d3e4b5651d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Oct 2020 14:32:46 -0400
Subject: [PATCH 1241/2348] fix(schema+index): allow calling `mongoose.model()`
 with schema from a different Mongoose module instance

Fix #9449
---
 lib/index.js  | 4 ++--
 lib/schema.js | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index ce42cd8bc01..b76b831b848 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -485,10 +485,10 @@ Mongoose.prototype.model = function(name, schema, collection, skipInit) {
     schema = false;
   }
 
-  if (utils.isObject(schema) && !(schema.instanceOfSchema)) {
+  if (utils.isObject(schema) && !(schema instanceof Schema)) {
     schema = new Schema(schema);
   }
-  if (schema && !schema.instanceOfSchema) {
+  if (schema && !(schema instanceof Schema)) {
     throw new Error('The 2nd parameter to `mongoose.model()` should be a ' +
       'schema or a POJO');
   }
diff --git a/lib/schema.js b/lib/schema.js
index 02c54b7c1db..07f760453ac 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -450,8 +450,9 @@ Schema.prototype.defaultOptions = function(options) {
  */
 
 Schema.prototype.add = function add(obj, prefix) {
-  if (obj instanceof Schema) {
+  if (obj instanceof Schema || (obj != null && obj.instanceOfSchema)) {
     merge(this, obj);
+
     return this;
   }
 

From d02c38588c952b53f795e0ec43c2bd049fac44e2 Mon Sep 17 00:00:00 2001
From: William Sheu <sheu.william@gmail.com>
Date: Thu, 1 Oct 2020 12:32:12 -0700
Subject: [PATCH 1242/2348] fix(transaction): fix saving new documents w/
 arrays in transactions

---
 lib/plugins/trackTransaction.js       |  2 +-
 test/es-next/transactions.test.es6.js | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index 4a7ddc45c5d..410a596f3bc 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -84,7 +84,7 @@ function mergeAtomics(destination, source) {
     destination.$addToSet = (destination.$addToSet || []).concat(source.$addToSet);
   }
   if (source.$set != null) {
-    destination.$set = Object.assign(destination.$set, source.$set);
+    destination.$set = Object.assign(destination.$set || {}, source.$set);
   }
 
   return destination;
diff --git a/test/es-next/transactions.test.es6.js b/test/es-next/transactions.test.es6.js
index 560bcbfc33c..1158361c072 100644
--- a/test/es-next/transactions.test.es6.js
+++ b/test/es-next/transactions.test.es6.js
@@ -404,4 +404,19 @@ describe('transactions', function() {
     assert.deepEqual(newDoc.arr, []);
     assert.deepEqual(newDoc.arr2, ['foo', 'bar']);
   });
+
+  it('can save a new document with an array', async function () {
+    const schema = Schema({ arr: [String] });
+
+    const Test = db.model('new_doc_array', schema);
+
+    await Test.createCollection();
+    const doc = new Test({ arr: ['foo'] });
+    await db.transaction(async (session) => {
+      await doc.save({ session });
+    });
+
+    const createdDoc = await Test.collection.findOne();
+    assert.deepEqual(createdDoc.arr, ['foo']);
+  });
 });

From 8169ac30c9159efaa7b6f3ecbfe046911379266e Mon Sep 17 00:00:00 2001
From: Craig Davis <craig-davis@users.noreply.github.com>
Date: Thu, 1 Oct 2020 16:08:41 -0700
Subject: [PATCH 1243/2348] Fix minor documentation spelling errors

* Fix query_casting.md
* Fix missing t in contributing guidelines
---
 CONTRIBUTING.md                 | 2 +-
 docs/tutorials/query_casting.md | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9c85b7eba88..d6f6988784c 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -55,7 +55,7 @@ If you'd like to preview your documentation changes, first commit your changes t
 * `make gendocs`
 * `node static.js`
 
-Visit `http://localhost:8088` and you should see the docs with your local changes. Make sure you `git reset --hard` before commiting, because changes to `docs/*` should **not** be in PRs.
+Visit `http://localhost:8088` and you should see the docs with your local changes. Make sure you `git reset --hard` before committing, because changes to `docs/*` should **not** be in PRs.
 
 ### Plugins website
 
diff --git a/docs/tutorials/query_casting.md b/docs/tutorials/query_casting.md
index 2675bc279f7..0ce03a09902 100644
--- a/docs/tutorials/query_casting.md
+++ b/docs/tutorials/query_casting.md
@@ -27,7 +27,7 @@ By default, Mongoose does **not** cast filter properties that aren't in your sch
 [require:Cast Tutorial.*not in schema]
 ```
 
-You can configure this behavior using the [`strictQuery` option for schemas](https://mongoosejs.com/docs/guide.html#strictQuery). This option is analagous to the [`strict` option](https://mongoosejs.com/docs/guide.html#strict). Setting `strictQuery` to `true` removes non-schema properties from the filter:
+You can configure this behavior using the [`strictQuery` option for schemas](https://mongoosejs.com/docs/guide.html#strictQuery). This option is analogous to the [`strict` option](https://mongoosejs.com/docs/guide.html#strict). Setting `strictQuery` to `true` removes non-schema properties from the filter:
 
 ```javascript
 [require:Cast Tutorial.*strictQuery true]

From b905d0c527f6ff618b2f82ba61c3627430fd0521 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Oct 2020 16:27:51 -0400
Subject: [PATCH 1244/2348] test(model): repro #9447

---
 test/model.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index d703a07dc6e..c85161064b4 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6251,6 +6251,18 @@ describe('Model', function() {
         assert.deepEqual(res.map(v => v.name), ['alpha', 'Zeta']);
       });
     });
+
+    it('createCollection() handles NamespaceExists errors (gh-9447)', function() {
+      const userSchema = new Schema({ name: String });
+      const Model = db.model('User', userSchema);
+
+      return co(function*() {
+        yield Model.collection.drop().catch(() => {});
+
+        yield Model.createCollection();
+        yield Model.createCollection();
+      });
+    });
   });
 
   it('dropDatabase() after init allows re-init (gh-6967)', function() {

From b4be141abe1c51eb6aa61cf552778abe919b790f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Oct 2020 16:28:00 -0400
Subject: [PATCH 1245/2348] fix(model): make `createCollection()` not throw
 error when collection already exists to be consistent with v5.9

Fix #9447
---
 lib/model.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 5b823674d39..0a18018ed67 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1326,7 +1326,8 @@ Model.createCollection = function createCollection(options, callback) {
     cb = this.$wrapCallback(cb);
 
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
-      if (error) {
+      if (error != null && error.codeName !== 'NamespaceExists') {
+        console.log('XF', error);
         return cb(error);
       }
       this.collection = this.db.collection(this.collection.collectionName, options);

From 049b6e21d2ec988f51c0029609a63268a5313377 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Oct 2020 12:30:30 -0400
Subject: [PATCH 1246/2348] test(document): repro #9448

---
 test/document.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 4450453e83e..eafbb8c3743 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9436,4 +9436,16 @@ describe('document', function() {
     const err = test.validateSync();
     assert.ifError(err);
   });
+
+  it('init tracks cast error reason (gh-9448)', function() {
+    const Test = db.model('Test', Schema({
+      num: Number
+    }));
+
+    const doc = new Test();
+    doc.init({ num: 'not a number' });
+
+    const err = doc.validateSync();
+    assert.ok(err.errors['num'].reason);
+  });
 });

From 44d519950f22a0e9a85c348ebbba5c63d5e7d7fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Oct 2020 12:30:43 -0400
Subject: [PATCH 1247/2348] fix(document): track `reason` on cast errors that
 occur while init-ing a document

Fix #9448
---
 lib/document.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 8434d6f88a2..11dece69181 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -692,7 +692,8 @@ function init(self, obj, doc, opts, prefix) {
               path: e.path,
               message: e.message,
               type: 'cast',
-              value: e.value
+              value: e.value,
+              reason: e
             }));
           }
         } else {

From 4da58f8a4b7841f9cdf8da26ad3ee5389b88b63d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Oct 2020 18:20:28 -0400
Subject: [PATCH 1248/2348] docs(connections): add SSL connections doc

Fix #9443
---
 docs/guides.pug       |  1 +
 docs/layout.pug       |  3 ++
 docs/tutorials/ssl.md | 67 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+)
 create mode 100644 docs/tutorials/ssl.md

diff --git a/docs/guides.pug b/docs/guides.pug
index 20c220c949f..04f6312edb3 100644
--- a/docs/guides.pug
+++ b/docs/guides.pug
@@ -60,6 +60,7 @@ block content
     * [Transactions](/docs/transactions.html)
     * [MongoDB Driver Deprecation Warnings](/docs/deprecations.html)
     * [Testing with Jest](/docs/jest.html)
+    * [SSL Connections](/docs/tutorials/ssl.html)
 
     ### Migration Guides
 
diff --git a/docs/layout.pug b/docs/layout.pug
index 4efd04f7c6d..19dd84ce0a7 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -69,6 +69,9 @@ html(lang='en')
                 a.pure-menu-link(href="/docs/schematypes.html", class=outputUrl === '/docs/schematypes.html' ? 'selected' : '') SchemaTypes
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/connections.html", class=outputUrl === '/docs/connections.html' ? 'selected' : '') Connections
+              - if (['/docs/connections', '/docs/tutorials/ssl'].some(path => outputUrl.startsWith(path)))
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/tutorials/ssl.html", class=outputUrl === '/docs/tutorials/ssl.html' ? 'selected' : '') SSL Connections
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/models.html", class=outputUrl === '/docs/models.html' ? 'selected' : '') Models
               li.pure-menu-item.sub-item
diff --git a/docs/tutorials/ssl.md b/docs/tutorials/ssl.md
new file mode 100644
index 00000000000..1c188f78903
--- /dev/null
+++ b/docs/tutorials/ssl.md
@@ -0,0 +1,67 @@
+# SSL Connections
+
+Mongoose supports connecting to [MongoDB clusters that require SSL connections](https://docs.mongodb.com/manual/tutorial/configure-ssl/). Setting the `ssl` option to `true` in [`mongoose.connect()`](/docs/api/mongoose.html#mongoose_Mongoose-connect) or your connection string is enough to connect to a MongoDB cluster using SSL:
+
+```javascript
+mongoose.connect('mongodb://localhost:27017/test', { ssl: true });
+
+// Equivalent:
+mongoose.connect('mongodb://localhost:27017/test?ssl=true');
+```
+
+If you try to connect to a MongoDB cluster that requires SSL without enabling the `ssl` option, `mongoose.connect()`
+will error out with the below error:
+
+```javascript
+MongooseServerSelectionError: connection <monitor> to 127.0.0.1:27017 closed
+    at NativeConnection.Connection.openUri (/node_modules/mongoose/lib/connection.js:800:32)
+    ...
+```
+
+## SSL Validation
+
+By default, Mongoose validates the SSL certificate against a [certificate authority](https://en.wikipedia.org/wiki/Certificate_authority) to ensure the SSL certificate is valid. To disable this validation, set the `sslValidate` option
+to `false`.
+
+```javascript
+mongoose.connect('mongodb://localhost:27017/test', {
+  ssl: true,
+  sslValidate: false
+});
+```
+
+In most cases, you should not disable SSL validation in production. However, `sslValidate: false` is often helpful
+for debugging SSL connection issues. If you can connect to MongoDB with `sslValidate: false`, but not with
+`sslValidate: true`, then you can confirm Mongoose can connect to the server and the server is configured to use
+SSL correctly, but there's some issue with the SSL certificate.
+
+For example, a common issue is the below error message:
+
+```
+MongooseServerSelectionError: unable to verify the first certificate
+```
+
+This error is often caused by [self-signed MongoDB certificates](https://medium.com/@rajanmaharjan/secure-your-mongodb-connections-ssl-tls-92e2addb3c89) or other situations where the certificate sent by the MongoDB
+server is not registered with an established certificate authority. The solution is to set the `sslCA` option, which
+[essentially sets a list of allowed SSL certificates](https://mongodb.github.io/node-mongodb-native/2.1/tutorials/connect/ssl/).
+
+```javascript
+await mongoose.connect('mongodb://localhost:27017/test', {
+  useNewUrlParser: true,
+  useUnifiedTopology: true,
+  ssl: true,
+  sslValidate: true,
+  // For example, see https://medium.com/@rajanmaharjan/secure-your-mongodb-connections-ssl-tls-92e2addb3c89
+  // for where the `rootCA.pem` file comes from
+  sslCA: require('fs').readFileSync(`${__dirname}/rootCA.pem`)
+});
+```
+
+Another common issue is the below error message:
+
+```
+MongooseServerSelectionError: Hostname/IP does not match certificate's altnames: Host: hostname1. is not cert's CN: hostname2
+```
+
+The SSL certificate's [common name](https://knowledge.digicert.com/solution/SO7239.html) **must** line up with the host name
+in your connection string. If the SSL certificate is for `hostname2.mydomain.com`, your connection string must connect to `hostname2.mydomain.com`, not any other hostname or IP address that may be equivalent to `hostname2.mydomain.com`. For replica sets, this also means that the SSL certificate's common name must line up with the [machine's `hostname`](/docs/connections.html#replicaset-hostnames).
\ No newline at end of file

From 18973c02204de4772d1d8fdfde6b05e2636ca167 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 13:24:13 -0400
Subject: [PATCH 1249/2348] test(document): repro #9459

---
 test/document.test.js | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index eafbb8c3743..d944ad11fae 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9448,4 +9448,46 @@ describe('document', function() {
     const err = doc.validateSync();
     assert.ok(err.errors['num'].reason);
   });
+
+  it('init tracks cast error reason (gh-9459)', function() {
+    const preferencesSchema = mongoose.Schema({
+      notifications: {
+        email: Boolean,
+        push: Boolean
+      },
+      keepSession: Boolean
+    }, { _id: false });
+
+    const User = db.model('User', Schema({
+      email: String,
+      username: String,
+      preferences: preferencesSchema
+    }));
+
+    const userFixture = {
+      email: 'foo@bar.com',
+      username: 'foobars',
+      preferences: {
+        keepSession: true,
+        notifications: {
+          email: false,
+          push: false
+        }
+      }
+    };
+
+    let userWithEmailNotifications = Object.assign({}, userFixture, {
+      'preferences.notifications': { email: true }
+    });
+    let testUser = new User(userWithEmailNotifications);
+
+    assert.deepEqual(testUser.toObject().preferences.notifications, { email: true });
+
+    userWithEmailNotifications = Object.assign({}, userFixture, {
+      'preferences.notifications.email': true
+    });
+    testUser = new User(userWithEmailNotifications);
+
+    assert.deepEqual(testUser.toObject().preferences.notifications, { email: true, push: false });
+  });
 });

From 978d695fb2f2714cc6c87978c560abda7b71de12 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 13:24:52 -0400
Subject: [PATCH 1250/2348] fix(schema): handle setting nested paths underneath
 single nested subdocs

Fix #9459
---
 lib/schema.js | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 07f760453ac..1ad65525857 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -715,6 +715,9 @@ Schema.prototype.path = function(path, obj) {
       this.singleNestedPaths[path + '.' + key] =
         schemaType.schema.subpaths[key];
     }
+    for (const key in schemaType.schema.nested) {
+      this.singleNestedPaths[path + '.' + key] = 'nested';
+    }
 
     Object.defineProperty(schemaType.schema, 'base', {
       configurable: true,
@@ -1124,8 +1127,10 @@ Schema.prototype.pathType = function(path) {
   if (this.subpaths.hasOwnProperty(cleanPath) || this.subpaths.hasOwnProperty(path)) {
     return 'real';
   }
-  if (this.singleNestedPaths.hasOwnProperty(cleanPath) || this.singleNestedPaths.hasOwnProperty(path)) {
-    return 'real';
+
+  const singleNestedPath = this.singleNestedPaths.hasOwnProperty(cleanPath) || this.singleNestedPaths.hasOwnProperty(path);
+  if (singleNestedPath) {
+    return singleNestedPath === 'nested' ? 'nested' : 'real';
   }
 
   // Look for maps

From 2da4cb355f787409e2f1f77203d09fb07a9ecb69 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 13:38:29 -0400
Subject: [PATCH 1251/2348] test(document): correct test title

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index d944ad11fae..33074529a94 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9449,7 +9449,7 @@ describe('document', function() {
     assert.ok(err.errors['num'].reason);
   });
 
-  it('init tracks cast error reason (gh-9459)', function() {
+  it('correctly handles setting nested path underneath single nested subdocs (gh-9459)', function() {
     const preferencesSchema = mongoose.Schema({
       notifications: {
         email: Boolean,

From 037eb14f33dc0d15e9e83ea727164e8c8787b41a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 13:55:28 -0400
Subject: [PATCH 1252/2348] fix(schema): avoid subdoc nested paths when getting
 schema paths for update

Re: #9459
---
 lib/schema.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 1ad65525857..db45ba78a54 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -782,6 +782,9 @@ Schema.prototype.path = function(path, obj) {
       schemaType.schema.subpaths[key].$isUnderneathDocArray = true;
     }
     for (const key of Object.keys(schemaType.schema.singleNestedPaths)) {
+      if (typeof schema.singleNestedPaths[cleanPath] !== 'object') {
+        continue;
+      }
       this.subpaths[path + '.' + key] = schemaType.schema.singleNestedPaths[key];
       schemaType.schema.singleNestedPaths[key].$isUnderneathDocArray = true;
     }
@@ -818,7 +821,7 @@ function _getPath(schema, path, cleanPath) {
   if (schema.subpaths.hasOwnProperty(cleanPath)) {
     return schema.subpaths[cleanPath];
   }
-  if (schema.singleNestedPaths.hasOwnProperty(cleanPath)) {
+  if (schema.singleNestedPaths.hasOwnProperty(cleanPath) && typeof schema.singleNestedPaths[cleanPath] === 'object') {
     return schema.singleNestedPaths[cleanPath];
   }
 

From e037a95ac83f2b52628a20b8a15ad3a6165d9f4e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 14:00:03 -0400
Subject: [PATCH 1253/2348] test: fix tests

---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index db45ba78a54..809d80463d7 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -782,7 +782,7 @@ Schema.prototype.path = function(path, obj) {
       schemaType.schema.subpaths[key].$isUnderneathDocArray = true;
     }
     for (const key of Object.keys(schemaType.schema.singleNestedPaths)) {
-      if (typeof schema.singleNestedPaths[cleanPath] !== 'object') {
+      if (typeof schemaType.schema.singleNestedPaths[cleanPath] !== 'object') {
         continue;
       }
       this.subpaths[path + '.' + key] = schemaType.schema.singleNestedPaths[key];

From 9ab14c84a6eac31ba7398ba788112eb7c942e752 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 15:27:39 -0400
Subject: [PATCH 1254/2348] chore(index.d.ts): add ts defs for more model
 functions and all aggregate functions

---
 index.d.ts                   | 175 +++++++++++++++++++++++++++++++++++
 lib/aggregate.js             |   7 +-
 test/typescript/aggregate.ts |  26 ++++++
 test/typescript/main.test.js |   5 +
 4 files changed, 209 insertions(+), 4 deletions(-)
 create mode 100644 test/typescript/aggregate.ts

diff --git a/index.d.ts b/index.d.ts
index c4d55172f7c..ba4d3be29d4 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -38,6 +38,9 @@ declare module "mongoose" {
   interface Model<T extends Document> {
     new(doc?: any): T;
 
+    aggregate<R>(pipeline?: any[]): Aggregate<Array<R>>;
+    aggregate<R>(pipeline: any[], cb: Function): Promise<Array<R>>;
+
     /** Base Mongoose instance the model uses. */
     base: typeof mongoose;
 
@@ -64,6 +67,12 @@ declare module "mongoose" {
     create(doc: T | DocumentDefinition<T>, callback: (err: Error | null, doc: T) => void): void;
     create(docs: Array<T | DocumentDefinition<T>>, callback: (err: Error | null, docs: Array<T>) => void): void;
 
+    /**
+     * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
+     * The document returned has no paths marked as modified initially.
+     */
+    hydrate(obj: any): T;
+
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T | InsertManyResult>;
     insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T> | InsertManyResult>;
@@ -82,6 +91,10 @@ declare module "mongoose" {
      **/
     startSession(options?: mongodb.SessionOptions, cb?: (err: any, session: mongodb.ClientSession) => void): Promise<mongodb.ClientSession>;
 
+    /** Casts and validates the given object against this model's schema, passing the given `context` to custom validators. */
+    validate(callback?: (err: any) => void): Promise<void>;
+    validate(optional: any, callback?: (err: any) => void): Promise<void>;
+
     /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
     watch(pipeline?: Array<object>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
 
@@ -134,8 +147,31 @@ declare module "mongoose" {
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: Error | null, res: Array<T>) => void): Query<Array<T>, T>;
+
+    /** Executes a mapReduce command. */
+    mapReduce<Key, Value>(
+      o: MapReduceOptions<T, Key, Value>,
+      callback?: (err: any, res: any) => void
+    ): Promise<any>;
+
     remove(filter?: any, callback?: (err: Error | null) => void): Query<any, T>;
 
+    /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+
+    /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+
+    /** Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option. */
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+
+    /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+
+    /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): Query<Array<T>, T>;
   }
@@ -165,6 +201,7 @@ declare module "mongoose" {
     collation?: mongodb.CollationDocument;
     session?: mongodb.ClientSession;
     explain?: any;
+    multi?: boolean;
   }
 
   interface SaveOptions {
@@ -189,6 +226,59 @@ declare module "mongoose" {
     mongoose?: { validationErrors?: Array<Error> }
   }
 
+  interface MapReduceOptions<T, Key, Val> {
+    map: Function | string;
+    reduce: (key: Key, vals: T[]) => Val;
+    /** query filter object. */
+    query?: any;
+    /** sort input objects using this key */
+    sort?: any;
+    /** max number of documents */
+    limit?: number;
+    /** keep temporary data default: false */
+    keeptemp?: boolean;
+    /** finalize function */
+    finalize?: (key: Key, val: Val) => Val;
+    /** scope variables exposed to map/reduce/finalize during execution */
+    scope?: any;
+    /** it is possible to make the execution stay in JS. Provided in MongoDB > 2.0.X default: false */
+    jsMode?: boolean;
+    /** provide statistics on job execution time. default: false */
+    verbose?: boolean;
+    readPreference?: string;
+    /** sets the output target for the map reduce job. default: {inline: 1} */
+    out?: {
+      /** the results are returned in an array */
+      inline?: number;
+      /**
+       * {replace: 'collectionName'} add the results to collectionName: the
+       * results replace the collection
+       */
+      replace?: string;
+      /**
+       * {reduce: 'collectionName'} add the results to collectionName: if
+       * dups are detected, uses the reducer / finalize functions
+       */
+      reduce?: string;
+      /**
+       * {merge: 'collectionName'} add the results to collectionName: if
+       * dups exist the new docs overwrite the old
+       */
+      merge?: string;
+    };
+  }
+
+  interface GeoSearchOptions {
+    /** x,y point to search for */
+    near: number[];
+    /** the maximum distance from the point near that a result can be */
+    maxDistance: number;
+    /** The maximum number of results to return */
+    limit?: number;
+    /** return the raw object instead of the Mongoose Model */
+    lean?: boolean;
+  }
+
   class Schema {
     /**
      * Create a new schema
@@ -395,4 +485,89 @@ declare module "mongoose" {
   export type UpdateQuery<T> = mongodb.UpdateQuery<T> & mongodb.MatchKeysAndValues<T>;
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Model<T>, '_id'>>
+
+  class Aggregate<R> {
+    /**
+     * Sets an option on this aggregation. This function will be deprecated in a
+     * future release. */
+    addCursorFlag(flag: string, value: boolean): this;
+
+    /** Sets the allowDiskUse option for the aggregation query (ignored for < 2.6.0) */
+    allowDiskUse(value: boolean): this;
+
+    /**
+     * Executes the query returning a `Promise` which will be
+     * resolved with either the doc(s) or rejected with the error.
+     * Like [`.then()`](#query_Query-then), but only takes a rejection handler.
+     */
+    catch: Promise<R>["catch"];
+
+    /** Adds a collation. */
+    collation(options: mongodb.CollationDocument): this;
+
+    /** Appends a new $count operator to this aggregate pipeline. */
+    count(countName: string): this;
+
+    /**
+     * Sets the cursor option option for the aggregation query (ignored for < 2.6.0).
+     */
+    cursor(options?: object): this;
+
+    /** Executes the aggregate pipeline on the currently bound Model. If cursor option is set, returns a cursor */
+    exec(callback?: (err: any, result: R) => void): Promise<R> | any;
+
+    /** Execute the aggregation with explain */
+    explain(callback?: (err: Error, result: any) => void): Promise<any>;
+
+    /** Combines multiple aggregation pipelines. */
+    facet(options: any): this;
+
+    /** Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection. */
+    graphLookup(options: any): this;
+
+    /** Sets the hint option for the aggregation query (ignored for < 3.6.0) */
+    hint(value: object | string): this;
+
+    /** Appends new custom $lookup operator to this aggregate pipeline. */
+    lookup(options: any): this;
+
+    /** Returns the current pipeline */
+    pipeline(): any[];
+
+    /** Sets the readPreference option for the aggregation query. */
+    read(pref: string | mongodb.ReadPreferenceMode, tags?: any[]): this;
+
+    /** Sets the readConcern level for the aggregation query. */
+    readConcern(level: string): this;
+
+    /** Appends a new $redact operator to this aggregate pipeline. */
+    redact(expression: any, thenExpr: string | any, elseExpr: string | any): this;
+
+    /**
+     * Helper for [Atlas Text Search](https://docs.atlas.mongodb.com/reference/atlas-search/tutorial/)'s
+     * `$search` stage.
+     */
+    search(options: any): this;
+
+    /** Lets you set arbitrary options, for middleware or plugins. */
+    option(value: object): this;
+
+    /** Appends new custom $sample operator to this aggregate pipeline. */
+    sample(size: number): this;
+
+    /** Sets the session for this aggregation. Useful for [transactions](/docs/transactions.html). */
+    session(session: mongodb.ClientSession | null): this;
+
+    /** Appends a new $sort operator to this aggregate pipeline. */
+    sort(arg: any): this;
+
+    /** Provides promise for aggregate. */
+    then: Promise<R>["then"];
+
+    /**
+     * Appends a new $sortByCount operator to this aggregate pipeline. Accepts either a string field name
+     * or a pipeline object.
+     */
+    sortByCount(arg: string | any): this;
+  }
 }
\ No newline at end of file
diff --git a/lib/aggregate.js b/lib/aggregate.js
index 6dc43926f86..1ad767fc2f5 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -471,7 +471,7 @@ Aggregate.prototype.sortByCount = function(arg) {
 };
 
 /**
- * Appends new custom $lookup operator(s) to this aggregate pipeline.
+ * Appends new custom $lookup operator to this aggregate pipeline.
  *
  * ####Examples:
  *
@@ -479,8 +479,7 @@ Aggregate.prototype.sortByCount = function(arg) {
  *
  * @see $lookup https://docs.mongodb.org/manual/reference/operator/aggregation/lookup/#pipe._S_lookup
  * @param {Object} options to $lookup as described in the above link
- * @return {Aggregate}
- * @api public
+ * @return {Aggregate}* @api public
  */
 
 Aggregate.prototype.lookup = function(options) {
@@ -523,7 +522,7 @@ Aggregate.prototype.graphLookup = function(options) {
 };
 
 /**
- * Appends new custom $sample operator(s) to this aggregate pipeline.
+ * Appends new custom $sample operator to this aggregate pipeline.
  *
  * ####Examples:
  *
diff --git a/test/typescript/aggregate.ts b/test/typescript/aggregate.ts
new file mode 100644
index 00000000000..f06eafaadce
--- /dev/null
+++ b/test/typescript/aggregate.ts
@@ -0,0 +1,26 @@
+import { Schema, model, Model, Types } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Model<ITest> {
+  _id?: Types.ObjectId,
+  name?: string;
+}
+
+const Test = model<ITest>('Test', schema);
+
+Test.aggregate([{ $match: { name: 'foo' } }]).exec().then((res: any) => console.log(res));
+
+Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).exec().then((res: Array<ITest>) => console.log(res[0].name));
+
+Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).then((res: Array<ITest>) => console.log(res[0].name));
+
+run().catch((err: Error) => console.log(err.stack));
+
+async function run() {
+  let res: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).exec();
+  console.log(res[0].name);
+
+  let res2: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]);
+  console.log(res2[0].name);
+}
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index a1f2f4e7dad..848256e7eb4 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -49,6 +49,11 @@ describe('typescript syntax', function() {
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.messageText.includes('No overload matches'), errors[0].messageText.messageText);
   });
+
+  it('aggregate', function() {
+    const errors = runTest('aggregate.ts');
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {

From be06df8213b7fd9f8ef3e23ad60bdeee97334694 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 20:23:20 -0400
Subject: [PATCH 1255/2348] chore: get rid of unnecessary log statement

---
 lib/model.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 0a18018ed67..2295e0437de 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1327,7 +1327,6 @@ Model.createCollection = function createCollection(options, callback) {
 
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
       if (error != null && error.codeName !== 'NamespaceExists') {
-        console.log('XF', error);
         return cb(error);
       }
       this.collection = this.db.collection(this.collection.collectionName, options);

From 3389dcfd367f1a2a9db953eed1135c43f81d2413 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 20:40:53 -0400
Subject: [PATCH 1256/2348] chore(index.d.ts): add type bindings for
 `discriminator()` and other static model functions re: #8108

---
 index.d.ts                       | 80 +++++++++++++++++++++++++++++++-
 test/typescript/discriminator.ts | 19 ++++++++
 test/typescript/main.test.js     |  5 ++
 3 files changed, 103 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/discriminator.ts

diff --git a/index.d.ts b/index.d.ts
index ba4d3be29d4..b9961700480 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -35,7 +35,7 @@ declare module "mongoose" {
   class Document {}
 
   export var Model: Model<any>;
-  interface Model<T extends Document> {
+  interface Model<T extends Document> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R>(pipeline?: any[]): Aggregate<Array<R>>;
@@ -67,23 +67,57 @@ declare module "mongoose" {
     create(doc: T | DocumentDefinition<T>, callback: (err: Error | null, doc: T) => void): void;
     create(docs: Array<T | DocumentDefinition<T>>, callback: (err: Error | null, docs: Array<T>) => void): void;
 
+    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
+    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: Error | null, collection: mongodb.Collection<T>) => void): void;
+
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
      * The document returned has no paths marked as modified initially.
      */
     hydrate(obj: any): T;
 
+    /**
+     * This function is responsible for building [indexes](https://docs.mongodb.com/manual/indexes/),
+     * unless [`autoIndex`](http://mongoosejs.com/docs/guide.html#autoIndex) is turned off.
+     * Mongoose calls this function automatically when a model is created using
+     * [`mongoose.model()`](/docs/api.html#mongoose_Mongoose-model) or
+     * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
+     * don't need to call it.
+     */
+    init(callback?: (err: any) => void): Promise<T>;
+
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T | InsertManyResult>;
     insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T> | InsertManyResult>;
     insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions, callback?: (err: Error | null, res: T | InsertManyResult) => void): void;
     insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions, callback?: (err: Error | null, res: Array<T> | InsertManyResult) => void): void;
 
+    /**
+     * Lists the indexes currently defined in MongoDB. This may or may not be
+     * the same as the indexes defined in your schema depending on whether you
+     * use the [`autoIndex` option](/docs/guide.html#autoIndex) and if you
+     * build indexes manually.
+     */
+    listIndexes(callback: (err: Error | null, res: Array<any>) => void): void;
+    listIndexes(): Promise<Array<any>>;
+
+    populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
+      callback?: (err: any, res: T[]) => void): Promise<Array<T>>;
+
     /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
     save(options?: SaveOptions): Promise<this>;
     save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
     save(fn?: (err: Error | null, doc: this) => void): void;
 
+    /**
+     * Makes the indexes in MongoDB match the indexes defined in this model's
+     * schema. This function will drop any indexes that are not defined in
+     * the model's schema except the `_id` index, and build any indexes that
+     * are in your schema but not in MongoDB.
+     */
+    syncIndexes(options?: object): Promise<Array<string>>;
+    syncIndexes(options: object | null, callback: (err: Error | null, dropped: Array<string>) => void): void;
+
     /**
      * Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
      * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
@@ -115,9 +149,33 @@ declare module "mongoose" {
     countDocuments(callback?: (err: any, count: number) => void): Query<number, T>;
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
 
+    /**
+     * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
+     * function.
+     */
+    createIndexes(options: any): Promise<void>;
+    createIndexes(options: any, callback?: (err: any) => void): Promise<void>;
+
+    /** Adds a discriminator type. */
+    discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
+
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
     estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T>;
 
+    /**
+     * Sends `createIndex` commands to mongo for each index declared in the schema.
+     * The `createIndex` commands are sent in series.
+     */
+    ensureIndexes(options: any): Promise<void>;
+    ensureIndexes(options: any, callback?: (err: any) => void): Promise<void>;
+
+    /**
+     * Returns true if at least one document exists in the database that matches
+     * the given `filter`, and false otherwise.
+     */
+    exists(filter: FilterQuery<T>): Promise<boolean>;
+    exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
+
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
 
@@ -279,6 +337,26 @@ declare module "mongoose" {
     lean?: boolean;
   }
 
+  interface PopulateOptions {
+    /** space delimited path(s) to populate */
+    path: string;
+    /** fields to select */
+    select?: any;
+    /** query conditions to match */
+    match?: any;
+    /** optional model to use for population */
+    model?: string | Model<any>;
+    /** optional query options like sort, limit, etc */
+    options?: any;
+    /** deep populate */
+    populate?: PopulateOptions | Array<PopulateOptions>;
+    /**
+     * If true Mongoose will always set `path` to an array, if false Mongoose will
+     * always set `path` to a document. Inferred from schema by default.
+     */
+    justOne?: boolean;
+  }
+
   class Schema {
     /**
      * Create a new schema
diff --git a/test/typescript/discriminator.ts b/test/typescript/discriminator.ts
new file mode 100644
index 00000000000..6444809083f
--- /dev/null
+++ b/test/typescript/discriminator.ts
@@ -0,0 +1,19 @@
+import { Schema, model, Model } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface IBaseTest extends Model<IBaseTest> {
+  name?: string;
+}
+
+interface IDiscriminatorTest extends IBaseTest {
+  email?: string;
+}
+
+const Base = model<IBaseTest>('Test', schema);
+const Disc = Base.discriminator<IDiscriminatorTest>('Test2', new Schema({ email: { type: String } }));
+
+const doc: IDiscriminatorTest = new Disc({ name: 'foo', email: 'hi' });
+
+doc.name = 'bar';
+doc.email = 'hello';
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 848256e7eb4..f46ad82a9e5 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -54,6 +54,11 @@ describe('typescript syntax', function() {
     const errors = runTest('aggregate.ts');
     assert.equal(errors.length, 0);
   });
+
+  it('discriminators', function() {
+    const errors = runTest('discriminator.ts');
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {

From be67bb993d20e510d13929df70b4d008994c8e03 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 4 Oct 2020 21:36:57 -0400
Subject: [PATCH 1257/2348] chore(index.d.ts): add schematype methods and
 statics re: #8108

---
 index.d.ts                                    | 82 +++++++++++++++++++
 .../typescript/createBasicSchemaDefinition.ts |  4 +-
 2 files changed, 85 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index b9961700480..60892357e29 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -365,6 +365,25 @@ declare module "mongoose" {
 
     /** Adds key path / schema type pairs to this schema. */
     add(obj: SchemaDefinition | Schema, prefix?: string): this;
+
+    /** Returns a copy of this schema */
+    clone(): Schema;
+
+    /** Iterates the schemas paths similar to Array#forEach. */
+    eachPath(fn: (path: string, type: SchemaType) => void): this;
+
+    /** Gets/sets schema paths. */
+    path(path: string): SchemaType;
+    path(path: string, constructor: any): this;
+
+    /** Returns the pathType of `path` for this schema. */
+    pathType(path: string): string;
+
+    /** Adds a method call to the queue. */
+    queue(name: string, args: any[]): this;
+
+    /** Returns an Array of path strings that are required by this schema. */
+    requiredPaths(invalidate?: boolean): string[];
   }
 
   interface SchemaDefinition {
@@ -648,4 +667,67 @@ declare module "mongoose" {
      */
     sortByCount(arg: string | any): this;
   }
+
+  class SchemaType {
+    /** SchemaType constructor */
+    constructor(path: string, options?: any, instance?: string);
+
+    /** Get/set the function used to cast arbitrary values to this type. */
+    static cast(caster?: Function | boolean): Function;
+
+    /** Sets a default option for this schema type. */
+    static set(option: string, value: any): void;
+
+    /** Attaches a getter for all instances of this schema type. */
+    static get(getter: (value: any) => any): void;
+
+    /** Sets a default value for this SchemaType. */
+    default(val: any): any;
+
+    /** Adds a getter to this schematype. */
+    get(fn: Function): this;
+
+    /**
+     * Defines this path as immutable. Mongoose prevents you from changing
+     * immutable paths unless the parent document has [`isNew: true`](/docs/api.html#document_Document-isNew).
+     */
+    immutable(bool: boolean): this;
+
+    /** Declares the index options for this schematype. */
+    index(options: any): this;
+
+    /**
+     * Set the model that this path refers to. This is the option that [populate](https://mongoosejs.com/docs/populate.html)
+     * looks at to determine the foreign collection it should query.
+     */
+    ref(ref: string | boolean | Model<any>): this;
+
+    /**
+     * Adds a required validator to this SchemaType. The validator gets added
+     * to the front of this SchemaType's validators array using unshift().
+     */
+    required(required: boolean, message?: string): this;
+
+    /** Sets default select() behavior for this path. */
+    select(val: boolean): this;
+
+    /** Adds a setter to this schematype. */
+    set(fn: Function): this;
+
+    /** Declares a sparse index. */
+    sparse(bool: boolean): this;
+
+    /** Declares a full text index. */
+    text(bool: boolean): this;
+
+    /** Defines a custom function for transforming this path when converting a document to JSON. */
+    transform(fn: (value: any) => any);
+
+    /** Declares an unique index. */
+    unique(bool: boolean): this;
+
+    /** Adds validator(s) for this document path. */
+    validate(obj: RegExp | Function | any, errorMsg?: string,
+      type?: string): this;
+  }
 }
\ No newline at end of file
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 73fed6b9402..b71d3fd2a60 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -9,4 +9,6 @@ interface ITest extends Model<ITest> {
 const Test = model<ITest>('Test', schema);
 
 const doc: ITest = new Test({ name: 'foo' });
-doc.name = 'bar';
\ No newline at end of file
+doc.name = 'bar';
+
+doc.save().then((doc: ITest) => console.log(doc.name));
\ No newline at end of file

From 3adad9ec9af84d721bba211fa59b24818ecaeae7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 5 Oct 2020 17:16:32 -0400
Subject: [PATCH 1258/2348] chore(index.d.ts): separate out document class and
 model interface re: #8108

---
 index.d.ts                                    | 59 ++++++++++++++++---
 test/typescript/aggregate.ts                  |  4 +-
 test/typescript/create.ts                     |  4 +-
 .../typescript/createBasicSchemaDefinition.ts |  4 +-
 test/typescript/discriminator.ts              |  4 +-
 test/typescript/maps.ts                       |  4 +-
 test/typescript/queries.ts                    |  4 +-
 test/typescript/subdocuments.ts               |  4 +-
 8 files changed, 66 insertions(+), 21 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 60892357e29..94c8eade380 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -28,11 +28,55 @@ declare module "mongoose" {
     autoCreate?: boolean;
   }
 
+  class Connection {}
+
+  class Collection {}
+
   namespace Types {
     class ObjectId extends mongodb.ObjectID {}
   }
 
-  class Document {}
+  class Document {
+    constructor(doc?: any);
+
+    /** Additional properties to attach to the query when calling `save()` and `isNew` is false. */
+    $where: object;
+
+    /** If this is a discriminator model, `baseModelName` is the name of the base model. */
+    baseModelName?: string;
+
+    /** Collection the model uses. */
+    collection: Collection;
+
+    /** Connection the model uses. */
+    db: Connection;
+
+    /** Removes this document from the db. */
+    delete(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
+    delete(options?: QueryOptions): Query<any, this>;
+
+    /** Removes this document from the db. */
+    deleteOne(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
+    deleteOne(options?: QueryOptions): Query<any, this>;
+
+    /** Signal that we desire an increment of this documents version. */
+    increment(): this;
+
+    /** Returns another Model instance. */
+    model<T extends Model<any>>(name: string): T;
+
+    /** The name of the model */
+    modelName: string;
+
+    /** Removes this document from the db. */
+    remove(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
+    remove(options?: QueryOptions): Query<any, this>;
+
+    /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
+    save(options?: SaveOptions): Promise<this>;
+    save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
+    save(fn?: (err: Error | null, doc: this) => void): void;
+  }
 
   export var Model: Model<any>;
   interface Model<T extends Document> extends NodeJS.EventEmitter {
@@ -70,6 +114,12 @@ declare module "mongoose" {
     createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
     createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: Error | null, collection: mongodb.Collection<T>) => void): void;
 
+    /**
+     * Event emitter that reports any errors that occurred. Useful for global error
+     * handling.
+     */
+    events: NodeJS.EventEmitter;
+
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
      * The document returned has no paths marked as modified initially.
@@ -104,11 +154,6 @@ declare module "mongoose" {
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
       callback?: (err: any, res: T[]) => void): Promise<Array<T>>;
 
-    /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
-    save(options?: SaveOptions): Promise<this>;
-    save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
-    save(fn?: (err: Error | null, doc: this) => void): void;
-
     /**
      * Makes the indexes in MongoDB match the indexes defined in this model's
      * schema. This function will drop any indexes that are not defined in
@@ -581,7 +626,7 @@ declare module "mongoose" {
   
   export type UpdateQuery<T> = mongodb.UpdateQuery<T> & mongodb.MatchKeysAndValues<T>;
 
-  export type DocumentDefinition<T> = Omit<T, Exclude<keyof Model<T>, '_id'>>
+  export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>
 
   class Aggregate<R> {
     /**
diff --git a/test/typescript/aggregate.ts b/test/typescript/aggregate.ts
index f06eafaadce..fa2034c5e89 100644
--- a/test/typescript/aggregate.ts
+++ b/test/typescript/aggregate.ts
@@ -1,8 +1,8 @@
-import { Schema, model, Model, Types } from 'mongoose';
+import { Schema, model, Document, Types } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
-interface ITest extends Model<ITest> {
+interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
 }
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
index a6cfd8eb456..edbdce4e83d 100644
--- a/test/typescript/create.ts
+++ b/test/typescript/create.ts
@@ -1,8 +1,8 @@
-import { Schema, model, Model, Types } from 'mongoose';
+import { Schema, model, Document, Types } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
-interface ITest extends Model<ITest> {
+interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
 }
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index b71d3fd2a60..1509bee635c 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -1,8 +1,8 @@
-import { Schema, model, Model } from 'mongoose';
+import { Schema, model, Document } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
-interface ITest extends Model<ITest> {
+interface ITest extends Document {
   name?: string;
 }
 
diff --git a/test/typescript/discriminator.ts b/test/typescript/discriminator.ts
index 6444809083f..b2829ed3e25 100644
--- a/test/typescript/discriminator.ts
+++ b/test/typescript/discriminator.ts
@@ -1,8 +1,8 @@
-import { Schema, model, Model } from 'mongoose';
+import { Schema, model, Document } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
-interface IBaseTest extends Model<IBaseTest> {
+interface IBaseTest extends Document {
   name?: string;
 }
 
diff --git a/test/typescript/maps.ts b/test/typescript/maps.ts
index 12f1e4cd2f1..59eaf591daa 100644
--- a/test/typescript/maps.ts
+++ b/test/typescript/maps.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Model } from 'mongoose';
+import { Schema, model, Document } from 'mongoose';
 
 const schema: Schema = new Schema({
   map1: {
@@ -18,7 +18,7 @@ const schema: Schema = new Schema({
   }
 });
 
-interface ITest extends Model<ITest> {
+interface ITest extends Document {
   map1: Map<string, number>,
   map2: Map<string, string>,
   map3: Map<string, number>
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 8042d772de7..f18bf1014f8 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,8 +1,8 @@
-import { Schema, model, Model, Types } from 'mongoose';
+import { Schema, model, Document, Types } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
-interface ITest extends Model<ITest> {
+interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
 }
diff --git a/test/typescript/subdocuments.ts b/test/typescript/subdocuments.ts
index 8f329ec8e79..19b132ad6af 100644
--- a/test/typescript/subdocuments.ts
+++ b/test/typescript/subdocuments.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Model } from 'mongoose';
+import { Schema, model, Document } from 'mongoose';
 
 const childSchema: Schema = new Schema({ name: String });
 
@@ -15,7 +15,7 @@ const schema: Schema = new Schema({
   }],
 });
 
-interface ITest extends Model<ITest> {
+interface ITest extends Document {
   child1: { name: String },
   child2: { name: String }
 }

From 0c4cd42e0f574234efcbd55889e0b99b77a64be7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 5 Oct 2020 17:38:37 -0400
Subject: [PATCH 1259/2348] chore: release 5.10.8

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index dbc18350d6a..34699d7bf83 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.10.8 / 2020-10-05
+===================
+ * fix(schema): handle setting nested paths underneath single nested subdocs #9459
+ * fix(schema+index): allow calling `mongoose.model()` with schema from a different Mongoose module instance #9449
+ * fix(transaction): fix saving new documents w/ arrays in transactions #9457 [PenguinToast](https://github.com/PenguinToast)
+ * fix(document): track `reason` on cast errors that occur while init-ing a document #9448
+ * fix(model): make `createCollection()` not throw error when collection already exists to be consistent with v5.9 #9447
+ * docs(connections): add SSL connections docs #9443
+ * docs(query_casting): fix typo #9458 [craig-davis](https://github.com/craig-davis)
+
 5.10.7 / 2020-09-24
 ===================
  * fix(schema): set correct path and schema on nested primitive arrays #9429
diff --git a/package.json b/package.json
index 0160250c1d7..fd8d71f7e67 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.7",
+  "version": "5.10.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 4ffccd6047eea503734651cb10f09eac48739bfc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 5 Oct 2020 18:37:42 -0400
Subject: [PATCH 1260/2348] chore(index.d.ts): add connection method and
 createConnection() typedefs re: #8108

---
 index.d.ts                    | 154 +++++++++++++++++++++++++++++++++-
 test/typescript/connection.ts |  11 +++
 test/typescript/main.test.js  |   5 ++
 3 files changed, 169 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/connection.ts

diff --git a/index.d.ts b/index.d.ts
index 94c8eade380..5d450787f61 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,4 +1,5 @@
 declare module "mongoose" {
+  import events = require('events');
   import mongodb = require('mongodb');
   import mongoose = require('mongoose');
 
@@ -7,6 +8,11 @@ declare module "mongoose" {
   export function connect(uri: string, callback: (err: Error) => void): void;
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
 
+  /** Creates a Connection instance. */
+  export function createConnection(uri: string, options?: ConnectOptions): Promise<Connection>;
+  export function createConnection(): Connection;
+  export function createConnection(uri: string, options: ConnectOptions, callback: (err: Error | null, conn: Connection) => void): void;
+
   export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
 
   type Mongoose = typeof mongoose;
@@ -28,7 +34,153 @@ declare module "mongoose" {
     autoCreate?: boolean;
   }
 
-  class Connection {}
+  class Connection extends events.EventEmitter {
+    /** Closes the connection */
+    close(callback: (err: Error | null) => void): void;
+    close(force: boolean, callback: (err: Error | null) => void): void;
+    close(force?: boolean): Promise<void>;
+
+    /** Retrieves a collection, creating it if not cached. */
+    collection(name: string, options: mongodb.CollectionCreateOptions): Collection;
+
+    /** A hash of the collections associated with this connection */
+    collections: { [index: string]: Collection };
+
+    /** A hash of the global options that are associated with this connection */
+    config: any;
+
+    /**
+     * Helper for `createCollection()`. Will explicitly create the given collection
+     * with specified options. Used to create [capped collections](https://docs.mongodb.com/manual/core/capped-collections/)
+     * and [views](https://docs.mongodb.com/manual/core/views/) from mongoose.
+     */
+    createCollection<T = any>(name: string, options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
+    createCollection<T = any>(name: string, cb: (err: Error | null, collection: mongodb.Collection<T>) => void): void;
+    createCollection<T = any>(name: string, options: mongodb.CollectionCreateOptions, cb?: (err: Error | null, collection: mongodb.Collection) => void): Promise<mongodb.Collection<T>>;
+
+    /**
+     * Removes the model named `name` from this connection, if it exists. You can
+     * use this function to clean up any models you created in your tests to
+     * prevent OverwriteModelErrors.
+     */
+    deleteModel(name: string): this;
+
+    /**
+     * Helper for `dropCollection()`. Will delete the given collection, including
+     * all documents and indexes.
+     */
+    dropCollection(collection: string): Promise<void>;
+    dropCollection(collection: string, cb: (err: Error | null) => void): void;
+
+    /**
+     * Helper for `dropDatabase()`. Deletes the given database, including all
+     * collections, documents, and indexes.
+     */
+    dropDatabase(): Promise<void>;
+    dropDatabase(cb: (err: Error | null) => void): void;
+
+    /** Gets the value of the option `key`. Equivalent to `conn.options[key]` */
+    get(key: string): any;
+
+    /**
+     * Returns the [MongoDB driver `MongoClient`](http://mongodb.github.io/node-mongodb-native/3.5/api/MongoClient.html) instance
+     * that this connection uses to talk to MongoDB.
+     */
+    getClient(): mongodb.MongoClient;
+
+    /**
+     * The host name portion of the URI. If multiple hosts, such as a replica set,
+     * this will contain the first host name in the URI
+     */
+    host: string;
+
+    /**
+     * A number identifier for this connection. Used for debugging when
+     * you have [multiple connections](/docs/connections.html#multiple_connections).
+     */
+    id: number;
+
+    /**
+     * A [POJO](https://masteringjs.io/tutorials/fundamentals/pojo) containing
+     * a map from model names to models. Contains all models that have been
+     * added to this connection using [`Connection#model()`](/docs/api/connection.html#connection_Connection-model).
+     */
+    models: { [index: string]: Model<any> };
+
+    /** Defines or retrieves a model. */
+    model<T extends Document>(name: string, schema?: Schema, collection?: string): Model<T>;
+
+    /** Returns an array of model names created on this connection. */
+    modelNames(): Array<string>;
+
+    /** The name of the database this connection points to. */
+    name: string;
+
+    /** Opens the connection with a URI using `MongoClient.connect()`. */
+    openUri(uri: string, options?: ConnectOptions): Promise<Connection>;
+    openUri(uri: string, callback: (err: Error | null, conn?: Connection) => void): Connection;
+    openUri(uri: string, options: ConnectOptions, callback: (err: Error | null, conn?: Connection) => void): Connection;
+
+    /** The password specified in the URI */
+    pass: string;
+
+    /**
+     * The port portion of the URI. If multiple hosts, such as a replica set,
+     * this will contain the port from the first host name in the URI.
+     */
+    port: number;
+
+    /** Declares a plugin executed on all schemas you pass to `conn.model()` */
+    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
+
+    /** The plugins that will be applied to all models created on this connection. */
+    plugins: Array<any>;
+
+    /**
+     * Connection ready state
+     * 
+     * - 0 = disconnected
+     * - 1 = connected
+     * - 2 = connecting
+     * - 3 = disconnecting
+     */
+    readyState: number;
+
+    /** Sets the value of the option `key`. Equivalent to `conn.options[key] = val` */
+    set(key: string, value: any): any;
+
+    /**
+     * Set the [MongoDB driver `MongoClient`](http://mongodb.github.io/node-mongodb-native/3.5/api/MongoClient.html) instance
+     * that this connection uses to talk to MongoDB. This is useful if you already have a MongoClient instance, and want to
+     * reuse it.
+     */
+    setClient(client: mongodb.MongoClient): this;
+
+    /**
+     * _Requires MongoDB >= 3.6.0._ Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
+     * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
+     * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
+     */
+    startSession(options?: mongodb.SessionOptions): Promise<mongodb.ClientSession>;
+    startSession(options: mongodb.SessionOptions, cb: (err: any, session: mongodb.ClientSession) => void): void;
+
+    /**
+     * _Requires MongoDB >= 3.6.0._ Executes the wrapped async function
+     * in a transaction. Mongoose will commit the transaction if the
+     * async function executes successfully and attempt to retry if
+     * there was a retriable error.
+     */
+    transaction(fn: (session: mongodb.ClientSession) => Promise<any>);
+
+    /** Switches to a different database using the same connection pool. */
+    useDb(name: string, options?: { useCache?: boolean }): Connection;
+
+    /** The username specified in the URI */
+    user: string;
+
+    /** Watches the entire underlying database for changes. Similar to [`Model.watch()`](/docs/api/model.html#model_Model.watch). */
+    watch(pipeline?: Array<any>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
+  }
 
   class Collection {}
 
diff --git a/test/typescript/connection.ts b/test/typescript/connection.ts
new file mode 100644
index 00000000000..1d8f0c19651
--- /dev/null
+++ b/test/typescript/connection.ts
@@ -0,0 +1,11 @@
+import { createConnection, Schema, Connection } from 'mongoose';
+
+const conn = createConnection();
+
+conn.model('Test', new Schema({ name: { type: String } }));
+
+conn.openUri('mongodb://localhost:27017/test').then(() => console.log('Connected!'));
+
+createConnection('mongodb://localhost:27017/test', { useNewUrlParser: true }).then((conn: Connection) => {
+  conn.host;
+});
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index f46ad82a9e5..291b2ffe12a 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -59,6 +59,11 @@ describe('typescript syntax', function() {
     const errors = runTest('discriminator.ts');
     assert.equal(errors.length, 0);
   });
+
+  it('multiple connections', function() {
+    const errors = runTest('connection.ts');
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {

From 690bacb3bfce55c69513234b170ad9f3b65e545f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 6 Oct 2020 15:30:06 -0400
Subject: [PATCH 1261/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 790f1e2e2b1..5ac0872a955 100644
--- a/index.pug
+++ b/index.pug
@@ -364,6 +364,9 @@ html(lang='en')
               <a rel="sponsored" href="https://casinopro.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinopro/4729b46/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://masonslots.com/">
+                <img class="sponsor" src="https://images.opencollective.com/masonslots/29251dd/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 0335578a9cd6528ac2bc1f2325e8a4400c68df1c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 6 Oct 2020 16:26:44 -0400
Subject: [PATCH 1262/2348] fix(mongoose): allow setting `autoCreate` as a
 global option to be consistent with `autoIndex`

Fix #9466
---
 lib/index.js        | 1 +
 lib/model.js        | 5 ++---
 lib/validoptions.js | 1 +
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index b76b831b848..fccb625bd62 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -166,6 +166,7 @@ Mongoose.prototype.driver = require('./driver');
  * - 'typePojoToMixed': true by default, may be `false` or `true`. Sets the default typePojoToMixed for schemas.
  * - 'maxTimeMS': If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query
  * - 'autoIndex': true by default. Set to false to disable automatic index creation for all models associated with this Mongoose instance.
+ * - 'autoCreate': Set to `true` to make Mongoose call [`Model.createCollection()`](/docs/api/model.html#model_Model.createCollection) automatically when you create a model with `mongoose.model()` or `conn.model()`. This is useful for testing transactions, change streams, and other features that require the collection to exist.
  *
  * @param {String} key
  * @param {String|Function|Boolean} value
diff --git a/lib/model.js b/lib/model.js
index 2295e0437de..0c1e8ccb701 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1236,9 +1236,8 @@ Model.init = function init(callback) {
   const Promise = PromiseProvider.get();
   const autoIndex = utils.getOption('autoIndex',
     this.schema.options, this.db.config, this.db.base.options);
-  const autoCreate = this.schema.options.autoCreate == null ?
-    this.db.config.autoCreate :
-    this.schema.options.autoCreate;
+  const autoCreate = utils.getOption('autoCreate',
+    this.schema.options, this.db.config, this.db.base.options);
 
   const _ensureIndexes = autoIndex ?
     cb => this.ensureIndexes({ _automatic: true }, cb) :
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 6e50ec6b69d..510d7e277e7 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -8,6 +8,7 @@
 const VALID_OPTIONS = Object.freeze([
   'applyPluginsToChildSchemas',
   'applyPluginsToDiscriminators',
+  'autoCreate',
   'autoIndex',
   'bufferCommands',
   'cloneSchemas',

From 8be015574075fd3beb4513ebe5c6713f92d080e4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 6 Oct 2020 18:11:58 -0400
Subject: [PATCH 1263/2348] chore(index.d.ts): add validation error and more
 document properties re: #8108

---
 index.d.ts | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 5d450787f61..25014e5a76a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -191,6 +191,13 @@ declare module "mongoose" {
   class Document {
     constructor(doc?: any);
 
+    /**
+     * Empty object that you can use for storing properties on the document. This
+     * is handy for passing data to middleware without conflicting with Mongoose
+     * internals.
+     */
+    $locals: object;
+
     /** Additional properties to attach to the query when calling `save()` and `isNew` is false. */
     $where: object;
 
@@ -211,9 +218,18 @@ declare module "mongoose" {
     deleteOne(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
     deleteOne(options?: QueryOptions): Query<any, this>;
 
+    /** Hash containing current validation errors. */
+    errors?: ValidationError;
+
+    /** The string version of this documents _id. */
+    id: string;
+
     /** Signal that we desire an increment of this documents version. */
     increment(): this;
 
+    /** Boolean flag specifying if the document is new. */
+    isNew: boolean;
+
     /** Returns another Model instance. */
     model<T extends Model<any>>(name: string): T;
 
@@ -228,6 +244,9 @@ declare module "mongoose" {
     save(options?: SaveOptions): Promise<this>;
     save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
     save(fn?: (err: Error | null, doc: this) => void): void;
+
+    /** The documents schema. */
+    schema: Schema;
   }
 
   export var Model: Model<any>;
@@ -927,4 +946,29 @@ declare module "mongoose" {
     validate(obj: RegExp | Function | any, errorMsg?: string,
       type?: string): this;
   }
+
+  class ValidationError extends Error {
+    name: 'ValidationError';
+
+    errors: {[path: string]: ValidatorError | CastError};
+  }
+
+  class CastError extends Error {
+    name: 'CastError';
+    stringValue: string;
+    kind: string;
+    value: any;
+    path: string;
+    reason?: any;
+    model?: any;
+  }
+
+  class ValidatorError extends Error {
+    name: 'ValidatorError';
+    properties: {message: string, type?: string, path?: string, value?: any, reason?: any};
+    kind: string;
+    path: string;
+    value: any;
+    reason?: Error | null;
+  }
 }
\ No newline at end of file

From 6538e4977778cbb70c267e0541ca952b5b4aa9b2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 7 Oct 2020 17:05:08 -0400
Subject: [PATCH 1264/2348] test(update): repro #9468

---
 test/model.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index c85161064b4..34b3a4e484d 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5022,6 +5022,32 @@ describe('Model', function() {
         });
       });
 
+      it('avoids unused array filter error (gh-9468)', function() {
+        return co(function*() {
+          const MyModel = db.model('Test', new Schema({
+            _id: Number,
+            grades: [Number]
+          }));
+
+          yield MyModel.create([
+            { _id: 1, grades: [95, 92, 90] },
+            { _id: 2, grades: [98, 100, 102] },
+            { _id: 3, grades: [95, 110, 100] }
+          ]);
+
+          yield MyModel.updateMany({}, { $set: { 'grades.0': 100 } }, {
+            arrayFilters: [{
+              element: { $gte: 95 }
+            }]
+          });
+
+          const docs = yield MyModel.find().sort({ _id: 1 });
+          assert.deepEqual(docs[0].toObject().grades, [100, 92, 90]);
+          assert.deepEqual(docs[1].toObject().grades, [100, 100, 102]);
+          assert.deepEqual(docs[2].toObject().grades, [100, 110, 100]);
+        });
+      });
+
       describe('watch()', function() {
         before(function() {
           if (!process.env.REPLICA_SET) {

From c44eeb08dec9c85e446a32a04ac1b079d001af86 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 7 Oct 2020 17:05:22 -0400
Subject: [PATCH 1265/2348] fix(update): strip out unused array filters to
 avoid "filter was not used in the update" error

Fix #9468
---
 lib/helpers/update/removeUnusedArrayFilters.js | 18 ++++++++++++++++++
 lib/query.js                                   |  9 +++++++++
 2 files changed, 27 insertions(+)
 create mode 100644 lib/helpers/update/removeUnusedArrayFilters.js

diff --git a/lib/helpers/update/removeUnusedArrayFilters.js b/lib/helpers/update/removeUnusedArrayFilters.js
new file mode 100644
index 00000000000..d4606285212
--- /dev/null
+++ b/lib/helpers/update/removeUnusedArrayFilters.js
@@ -0,0 +1,18 @@
+'use strict';
+
+/**
+ * MongoDB throws an error if there's unused array filters. That is, if `options.arrayFilters` defines
+ * a filter, but none of the `update` keys use it. This should be enough to filter out all unused array
+ * filters.
+ */
+
+module.exports = function removeUnusedArrayFilters(update, arrayFilters) {
+  const updateKeys = Object.keys(update).map(key => Object.keys(update[key])).reduce((cur, arr) => cur.concat(arr), []);
+  return arrayFilters.filter(obj => {
+    const firstKey = Object.keys(obj)[0];
+    const firstDot = firstKey.indexOf('.');
+    const arrayFilterKey = firstDot === -1 ? firstKey : firstKey.slice(0, firstDot);
+
+    return updateKeys.find(key => key.includes('$[' + arrayFilterKey + ']')) != null;
+  });
+};
\ No newline at end of file
diff --git a/lib/query.js b/lib/query.js
index bb12be627e8..d4a41397c4e 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -25,6 +25,7 @@ const helpers = require('./queryhelpers');
 const isInclusive = require('./helpers/projection/isInclusive');
 const mquery = require('mquery');
 const parseProjection = require('./helpers/projection/parseProjection');
+const removeUnusedArrayFilters = require('./helpers/update/removeUnusedArrayFilters');
 const selectPopulatedFields = require('./helpers/query/selectPopulatedFields');
 const setDefaultsOnInsert = require('./helpers/setDefaultsOnInsert');
 const slice = require('sliced');
@@ -3534,6 +3535,10 @@ Query.prototype._findAndModify = function(type, callback) {
         }
       }
     }
+
+    if (Array.isArray(opts.arrayFilters)) {
+      opts.arrayFilters = removeUnusedArrayFilters(this._update, opts.arrayFilters);
+    }
   }
 
   this._applyPaths();
@@ -3770,6 +3775,10 @@ function _updateThunk(op, callback) {
       this._update, _opts);
   }
 
+  if (Array.isArray(options.arrayFilters)) {
+    options.arrayFilters = removeUnusedArrayFilters(this._update, options.arrayFilters);
+  }
+
   const runValidators = _getOption(this, 'runValidators', false);
   if (runValidators) {
     this.validate(this._update, options, isOverwriting, err => {

From 9c7eb406da6db693d6eecac91b8d4c89ee4685d9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 9 Oct 2020 10:29:47 -0400
Subject: [PATCH 1266/2348] chore(index.d.ts): add document query methods and
 `is*()` methods re: #8108

---
 index.d.ts                   | 99 ++++++++++++++++++++++++++++++++++++
 lib/document.js              |  5 +-
 test/typescript/main.test.js | 30 +++++++++++
 3 files changed, 132 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 25014e5a76a..337f7a1f460 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -191,6 +191,22 @@ declare module "mongoose" {
   class Document {
     constructor(doc?: any);
 
+    /** Don't run validation on this path or persist changes to this path. */
+    $ignore(path: string);
+
+    /** Checks if a path is set to its default. */
+    $isDefault(path: string);
+
+    /** Getter/setter, determines whether the document was removed or not. */
+    $isDeleted(val?: boolean);
+
+    /**
+     * Returns true if the given path is nullish or only contains empty objects.
+     * Useful for determining whether this subdoc will get stripped out by the
+     * [minimize option](/docs/guide.html#minimize).
+     */
+    $isEmpty(path: string);
+
     /**
      * Empty object that you can use for storing properties on the document. This
      * is handy for passing data to middleware without conflicting with Mongoose
@@ -198,6 +214,24 @@ declare module "mongoose" {
      */
     $locals: object;
 
+    /**
+     * A string containing the current operation that Mongoose is executing
+     * on this document. May be `null`, `'save'`, `'validate'`, or `'remove'`.
+     */
+    $op: string | null;
+
+    /**
+     * Getter/setter around the session associated with this document. Used to
+     * automatically set `session` if you `save()` a doc that you got from a
+     * query with an associated session.
+     */
+    $session(session?: mongodb.ClientSession | null): mongodb.ClientSession;
+
+    /** Alias for `set()`, used internally to avoid conflicts */
+    $set(path: string, val: any, options?: any): this;
+    $set(path: string, val: any, type: any, options?: any): this;
+    $set(value: any): this;
+
     /** Additional properties to attach to the query when calling `save()` and `isNew` is false. */
     $where: object;
 
@@ -218,33 +252,98 @@ declare module "mongoose" {
     deleteOne(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
     deleteOne(options?: QueryOptions): Query<any, this>;
 
+    /**
+     * Returns the list of paths that have been directly modified. A direct
+     * modified path is a path that you explicitly set, whether via `doc.foo = 'bar'`,
+     * `Object.assign(doc, { foo: 'bar' })`, or `doc.set('foo', 'bar')`.
+     */
+    directModifiedPaths(): Array<string>;
+
     /** Hash containing current validation errors. */
     errors?: ValidationError;
 
+    /** Returns the value of a path. */
+    get(path: string, type?: any, options?: any);
+
     /** The string version of this documents _id. */
     id: string;
 
     /** Signal that we desire an increment of this documents version. */
     increment(): this;
 
+    /**
+     * Initializes the document without setters or marking anything modified.
+     * Called internally after a document is returned from mongodb. Normally,
+     * you do **not** need to call this function on your own.
+     */
+    init(obj: any, opts?: any, cb?: (err: Error | null, doc: this) => void): this;
+
+    /** Returns true if `path` was directly set and modified, else false. */
+    isDirectModified(path: string): boolean;
+
+    /** Checks if `path` was explicitly selected. If no projection, always returns true. */
+    isDirectSelected(path: string): boolean;
+
+    /** Checks if `path` is in the `init` state, that is, it was set by `Document#init()` and not modified since. */
+    isInit(path: string);
+
+    /**
+     * Returns true if any of the given paths is modified, else false. If no arguments, returns `true` if any path
+     * in this document is modified.
+     */
+    isModified(path?: string | Array<string>): boolean;
+
+    /** Checks if `path` was selected in the source query which initialized this document. */
+    isSelected(path: string): boolean;
+
     /** Boolean flag specifying if the document is new. */
     isNew: boolean;
 
+    /** Marks the path as having pending changes to write to the db. */
+    markModified(path: string, scope?: any);
+
+    /** Returns the list of paths that have been modified. */
+    modifiedPaths(options?: { includeChildren?: boolean }): Array<string>;
+
     /** Returns another Model instance. */
     model<T extends Model<any>>(name: string): T;
 
     /** The name of the model */
     modelName: string;
 
+    /**
+     * Overwrite all values in this document with the values of `obj`, except
+     * for immutable properties. Behaves similarly to `set()`, except for it
+     * unsets all properties that aren't in `obj`.
+     */
+    overwrite(obj: DocumentDefinition<this>): this;
+
     /** Removes this document from the db. */
     remove(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
     remove(options?: QueryOptions): Query<any, this>;
 
+    /** Sends a replaceOne command with this document `_id` as the query selector. */
+    replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, this>;
+
     /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
     save(options?: SaveOptions): Promise<this>;
     save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
     save(fn?: (err: Error | null, doc: this) => void): void;
 
+    /** Sets the value of a path, or many paths. */
+    set(path: string, val: any, options?: any): this;
+    set(path: string, val: any, type: any, options?: any): this;
+    set(value: any): this;
+
+    /** Clears the modified state on the specified path. */
+    unmarkModified(path: string);
+
+    /** Sends an update command with this document `_id` as the query selector. */
+    update(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: Error, res: any) => void): Query<any, this>;
+
+    /** Sends an updateOne command with this document `_id` as the query selector. */
+    updateOne(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: Error, res: any) => void): Query<any, this>;
+
     /** The documents schema. */
     schema: Schema;
   }
diff --git a/lib/document.js b/lib/document.js
index 11dece69181..e3ee617680b 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1851,7 +1851,8 @@ Document.prototype.modifiedPaths = function(options) {
 Document.prototype[documentModifiedPaths] = Document.prototype.modifiedPaths;
 
 /**
- * Returns true if this document was modified, else false.
+ * Returns true if any of the given paths is modified, else false. If no arguments, returns `true` if any path
+ * in this document is modified.
  *
  * If `path` is given, checks if a path or any full path containing `path` as part of its path chain has been modified.
  *
@@ -1962,7 +1963,7 @@ Document.prototype.isDirectModified = function(path) {
 };
 
 /**
- * Checks if `path` was initialized.
+ * Checks if `path` is in the `init` state, that is, it was set by `Document#init()` and not modified since.
  *
  * @param {String} path
  * @return {Boolean}
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 291b2ffe12a..f82b2fdb571 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -14,54 +14,84 @@ describe('typescript syntax', function() {
 
   it('create schema and model', function() {
     const errors = runTest('createBasicSchemaDefinition.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 
   it('connect syntax', function() {
     const errors = runTest('connectSyntax.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 
   it('reports error on invalid getter syntax', function() {
     const errors = runTest('schemaGettersSetters.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.messageText.includes('incorrect: number'), errors[0].messageText.messageText);
   });
 
   it('handles maps', function() {
     const errors = runTest('maps.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.messageText.includes('not assignable'), errors[0].messageText.messageText);
   });
 
   it('subdocuments', function() {
     const errors = runTest('subdocuments.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 
   it('queries', function() {
     const errors = runTest('queries.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 
   it('create', function() {
     const errors = runTest('create.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.messageText.includes('No overload matches'), errors[0].messageText.messageText);
   });
 
   it('aggregate', function() {
     const errors = runTest('aggregate.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 
   it('discriminators', function() {
     const errors = runTest('discriminator.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 
   it('multiple connections', function() {
     const errors = runTest('connection.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
     assert.equal(errors.length, 0);
   });
 });

From e406afa5c16097526f610337d5b949d9bca207de Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 9 Oct 2020 11:39:39 -0400
Subject: [PATCH 1267/2348] chore: release 5.10.9

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 34699d7bf83..e1b569dca63 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.10.9 / 2020-10-09
+===================
+ * fix(update): strip out unused array filters to avoid "filter was not used in the update" error #9468
+ * fix(mongoose): allow setting `autoCreate` as a global option to be consistent with `autoIndex` #9466
+
 5.10.8 / 2020-10-05
 ===================
  * fix(schema): handle setting nested paths underneath single nested subdocs #9459
diff --git a/package.json b/package.json
index fd8d71f7e67..a9eae6d3867 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.8",
+  "version": "5.10.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From d41bce48b52363df93dbc6d39b126bed87969ac5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 9 Oct 2020 15:08:48 -0400
Subject: [PATCH 1268/2348] chore: remove stale copyright

Fix #9430
---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 5ac0872a955..a75cbd45af2 100644
--- a/index.pug
+++ b/index.pug
@@ -375,7 +375,7 @@ html(lang='en')
             to get your company's logo above!
           </div>
 
-    p#footer Licensed under MIT. Copyright 2011 <a href="http://learnboost.com">LearnBoost</a>.
+    p#footer Licensed under MIT.
     script.
       document.body.className = 'load';
     include docs/includes/track

From fa31bdf0b3556cd7cf37a53631f3d54777fd90c0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 9 Oct 2020 17:59:02 -0400
Subject: [PATCH 1269/2348] chore(index.d.ts): finish adding document methods
 re: #8108

---
 index.d.ts      | 81 +++++++++++++++++++++++++++++++++++++++++++++++++
 lib/document.js |  9 +++---
 2 files changed, 85 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 337f7a1f460..8c004218b94 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -207,6 +207,9 @@ declare module "mongoose" {
      */
     $isEmpty(path: string);
 
+    /** Checks if a path is invalid */
+    $isValid(path: string);
+
     /**
      * Empty object that you can use for storing properties on the document. This
      * is handy for passing data to middleware without conflicting with Mongoose
@@ -214,6 +217,9 @@ declare module "mongoose" {
      */
     $locals: object;
 
+    /** Marks a path as valid, removing existing validation errors. */
+    $markValid(path: string);
+
     /**
      * A string containing the current operation that Mongoose is executing
      * on this document. May be `null`, `'save'`, `'validate'`, or `'remove'`.
@@ -252,6 +258,9 @@ declare module "mongoose" {
     deleteOne(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
     deleteOne(options?: QueryOptions): Query<any, this>;
 
+    /** Takes a populated field and returns it to its unpopulated state. */
+    depopulate(path: string): this;
+
     /**
      * Returns the list of paths that have been directly modified. A direct
      * modified path is a path that you explicitly set, whether via `doc.foo = 'bar'`,
@@ -259,12 +268,31 @@ declare module "mongoose" {
      */
     directModifiedPaths(): Array<string>;
 
+    /**
+     * Returns true if this document is equal to another document.
+     *
+     * Documents are considered equal when they have matching `_id`s, unless neither
+     * document has an `_id`, in which case this function falls back to using
+     * `deepEqual()`.
+     */
+    equals(doc: Document): boolean;
+
     /** Hash containing current validation errors. */
     errors?: ValidationError;
 
+    /** Explicitly executes population and returns a promise. Useful for promises integration. */
+    execPopulate(): Promise<this>;
+    execPopulate(callback: (err: Error | null, res: this) => void): void;
+
     /** Returns the value of a path. */
     get(path: string, type?: any, options?: any);
 
+    /**
+     * Returns the changes that happened to the document
+     * in the format that will be sent to MongoDB.
+     */
+    getChanges(): UpdateQuery<this>;
+
     /** The string version of this documents _id. */
     id: string;
 
@@ -278,6 +306,9 @@ declare module "mongoose" {
      */
     init(obj: any, opts?: any, cb?: (err: Error | null, doc: this) => void): this;
 
+    /** Marks a path as invalid, causing validation to fail. */
+    invalidate(path: string, errorMsg: string | Error, value?: any, kind?: string): Error | null;
+
     /** Returns true if `path` was directly set and modified, else false. */
     isDirectModified(path: string): boolean;
 
@@ -318,6 +349,20 @@ declare module "mongoose" {
      */
     overwrite(obj: DocumentDefinition<this>): this;
 
+    /** If this document is a subdocument or populated document, returns the document's parent. Returns `undefined` otherwise. */
+    parent(): Document | undefined;
+
+    /**
+     * Populates document references, executing the `callback` when complete.
+     * If you want to use promises instead, use this function with
+     * [`execPopulate()`](#document_Document-execPopulate).
+     */
+    populate(path: string, callback?: (err: Error | null, res: this) => void): this;
+    populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: (err: Error | null, res: this) => void): this;
+
+    /** Gets _id(s) used during population of the given `path`. If the path was not populated, returns `undefined`. */
+    populated(path: string): any;
+
     /** Removes this document from the db. */
     remove(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
     remove(options?: QueryOptions): Query<any, this>;
@@ -335,6 +380,12 @@ declare module "mongoose" {
     set(path: string, val: any, type: any, options?: any): this;
     set(value: any): this;
 
+    /** The return value of this method is used in calls to JSON.stringify(doc). */
+    toJSON(options?: ToObjectOptions): any;
+
+    /** Converts this document into a plain-old JavaScript object ([POJO](https://masteringjs.io/tutorials/fundamentals/pojo)). */
+    toObject(options?: ToObjectOptions): any;
+
     /** Clears the modified state on the specified path. */
     unmarkModified(path: string);
 
@@ -344,6 +395,15 @@ declare module "mongoose" {
     /** Sends an updateOne command with this document `_id` as the query selector. */
     updateOne(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: Error, res: any) => void): Query<any, this>;
 
+    /** Executes registered validation rules for this document. */
+    validate(pathsToValidate?: Array<string>, options?: any): Promise<void>;
+    validate(callback: (err: Error | null) => void): void;
+    validate(pathsToValidate: Array<string>, callback: (err: Error | null) => void): void;
+    validate(pathsToValidate: Array<string>, options: any, callback: (err: Error | null) => void): void;
+
+    /** Executes registered validation rules (skipping asynchronous validators) for this document. */
+    validateSync(pathsToValidate?: Array<string>, options?: any): Error | null;
+
     /** The documents schema. */
     schema: Schema;
   }
@@ -672,6 +732,27 @@ declare module "mongoose" {
     justOne?: boolean;
   }
 
+  interface ToObjectOptions {
+    /** apply all getters (path and virtual getters) */
+    getters?: boolean;
+    /** apply virtual getters (can override getters option) */
+    virtuals?: boolean;
+    /** if `options.virtuals = true`, you can set `options.aliases = false` to skip applying aliases. This option is a no-op if `options.virtuals = false`. */
+    aliases?: boolean;
+    /** remove empty objects (defaults to true) */
+    minimize?: boolean;
+    /** if set, mongoose will call this function to allow you to transform the returned object */
+    transform?: (doc: any, ret: any, options: any) => any;
+    /** if true, replace any conventionally populated paths with the original id in the output. Has no affect on virtual populated paths. */
+    depopulate?: boolean;
+    /** if false, exclude the version key (`__v` by default) from the output */
+    versionKey?: boolean;
+    /** if true, convert Maps to POJOs. Useful if you want to `JSON.stringify()` the result of `toObject()`. */
+    flattenMaps?: boolean;
+    /** If true, omits fields that are excluded in this document's projection. Unless you specified a projection, this will omit any field that has `select: false` in the schema. */
+    useProjection?: boolean;
+  }
+
   class Schema {
     /**
      * Create a new schema
diff --git a/lib/document.js b/lib/document.js
index e3ee617680b..90da79b0dda 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3218,7 +3218,7 @@ Document.prototype.$toObject = function(options, json) {
 };
 
 /**
- * Converts this document into a plain javascript object, ready for storage in MongoDB.
+ * Converts this document into a plain-old JavaScript object ([POJO](https://masteringjs.io/tutorials/fundamentals/pojo)).
  *
  * Buffers are converted to instances of [mongodb.Binary](http://mongodb.github.com/node-mongodb-native/api-bson-generated/binary.html) for proper storage.
  *
@@ -3681,7 +3681,7 @@ Document.prototype.toString = function() {
 };
 
 /**
- * Returns true if the Document stores the same data as doc.
+ * Returns true if this document is equal to another document.
  *
  * Documents are considered equal when they have matching `_id`s, unless neither
  * document has an `_id`, in which case this function falls back to using
@@ -3810,8 +3810,7 @@ Document.prototype.populate = function populate() {
 };
 
 /**
- * Explicitly executes population and returns a promise. Useful for ES2015
- * integration.
+ * Explicitly executes population and returns a promise. Useful for promises integration.
  *
  * ####Example:
  *
@@ -3868,7 +3867,7 @@ Document.prototype.execPopulate = function(callback) {
  *       console.log(doc.populated('author')) // '5144cf8050f071d979c118a7'
  *     })
  *
- * If the path was not populated, undefined is returned.
+ * If the path was not populated, returns `undefined`.
  *
  * @param {String} path
  * @return {Array|ObjectId|Number|Buffer|String|undefined}

From 649172d977ea9bd1b9045b9960625bc0641cb3f2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 10 Oct 2020 14:36:56 -0400
Subject: [PATCH 1270/2348] chore(index.d.ts): add query helpers typescript
 definitions

Re: #8108
---
 index.d.ts   | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 lib/query.js |  52 +++++++++++++-------------
 2 files changed, 127 insertions(+), 28 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 8c004218b94..c77c04aa510 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -926,6 +926,19 @@ declare module "mongoose" {
 
     $where(argument: string | Function): Query<Array<DocType>, DocType>;
 
+    /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    all(val: Array<any>): this;
+    all(path: string, val: Array<any>): this;
+
+    /** Specifies arguments for an `$and` condition. */
+    and(array: Array<FilterQuery<DocType>>): this;
+
+    /** Specifies the batchSize option. */
+    batchSize(val: number): this;
+
+    /** Specifies the `comment` option. */
+    comment(val: string): this;
+
     /** Specifies this query as a `count` query. */
     count(callback?: (err: any, count: number) => void): Query<number, DocType>;
     count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
@@ -937,9 +950,20 @@ declare module "mongoose" {
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType>;
 
+    /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    elemMatch(val: Function | any): this;
+    elemMatch(path: string, val: Function | any): this;
+
+    /** Specifies the complementary comparison value for paths specified with `where()` */
+    equals(val: any): this;
+
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
     estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType>;
 
+    /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    exists(val: boolean): this;
+    exists(path: string, val: boolean): this;
+
     /** Creates a `find` query: gets a list of documents that match `filter`. */
     find(callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
     find(filter: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
@@ -960,8 +984,83 @@ declare module "mongoose" {
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
-    /** Creates a Query, applies the passed conditions, and returns the Query. */
-    where(path: string, val?: any): Query<Array<DocType>, DocType>;
+    /** Specifies a `$gt` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    gt(val: number): this;
+    gt(path: string, val: number): this;
+
+    /** Specifies a `$gte` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    gte(val: number): this;
+    gte(path: string, val: number): this;
+
+    /** Sets query hints. */
+    hint(val: any): this;
+
+    /** Specifies an `$in` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    in(val: Array<any>): this;
+    in(path: string, val: Array<any>): this;
+
+    /** Specifies the maximum number of documents the query will return. */
+    limit(val: number): this;
+
+    /** Specifies a `$lt` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    lt(val: number): this;
+    lt(path: string, val: number): this;
+
+    /** Specifies a `$lte` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    lte(val: number): this;
+    lte(path: string, val: number): this;
+
+    /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    maxDistance(val: number): this;
+    maxDistance(path: string, val: number): this;
+
+    /** Specifies the maxScan option. */
+    maxScan(val: number): this;
+
+    /** Specifies a `$mod` condition, filters documents for documents whose `path` property is a number that is equal to `remainder` modulo `divisor`. */
+    mod(val: Array<number>): this;
+    mod(path: string, val: Array<number>): this;
+
+    /** Specifies a `$ne` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    ne(val: any): this;
+    ne(path: string, val: any);
+
+    /** Specifies an `$nin` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    nin(val: Array<any>): this;
+    nin(path: string, val: Array<any>): this;
+
+    /** Specifies arguments for an `$nor` condition. */
+    nor(array: Array<FilterQuery<DocType>>): this;
+
+    /** Specifies arguments for an `$or` condition. */
+    or(array: Array<FilterQuery<DocType>>): this;
+
+    /** Specifies a `$regex` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    regex(val: string | RegExp): this;
+    regex(path: string, val: string | RegExp): this;
+
+    /** Specifies an `$size` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    size(val: number): this;
+    size(path: string, val: number): this;
+
+    /** Specifies the number of documents to skip. */
+    skip(val: number): this;
+
+    /** Specifies a `$slice` projection for an array. */
+    slice(val: number | Array<number>): this;
+    slice(path: string, val: number | Array<number>): this;
+
+    /** Specifies this query as a `snapshot` query. */
+    snapshot(val?: boolean): this;
+
+    /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
+    toConstructor(): new (filter?: FilterQuery<DocType>, options?: QueryOptions) => Query<ResultType, DocType>;
+
+    /** Specifies a path for use with chaining. */
+    where(path: string, val?: any): this;
+
+    /** Defines a `$within` or `$geoWithin` argument for geo-spatial queries. */
+    within(val?: any): this;
   }
 
   export type FilterQuery<T> = {
diff --git a/lib/query.js b/lib/query.js
index d4a41397c4e..f84365b8dda 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -273,6 +273,28 @@ Query.prototype.toConstructor = function toConstructor() {
  * @api public
  */
 
+/**
+ * Specifies a `$slice` projection for an array.
+ *
+ * ####Example
+ *
+ *     query.slice('comments', 5)
+ *     query.slice('comments', -5)
+ *     query.slice('comments', [10, 5])
+ *     query.where('comments').slice(5)
+ *     query.where('comments').slice([-10, 5])
+ *
+ * @method slice
+ * @memberOf Query
+ * @instance
+ * @param {String} [path]
+ * @param {Number} val number/range of elements to slice
+ * @return {Query} this
+ * @see mongodb http://www.mongodb.org/display/DOCS/Retrieving+a+Subset+of+Fields#RetrievingaSubsetofFields-RetrievingaSubrangeofArrayElements
+ * @see $slice http://docs.mongodb.org/manual/reference/projection/slice/#prj._S_slice
+ * @api public
+ */
+
 Query.prototype.slice = function() {
   if (arguments.length === 0) {
     return this;
@@ -458,7 +480,7 @@ Query.prototype.slice = function() {
  * @memberOf Query
  * @instance
  * @param {String} [path]
- * @param {Number} val
+ * @param {any} val
  * @api public
  */
 
@@ -472,7 +494,7 @@ Query.prototype.slice = function() {
  * @memberOf Query
  * @instance
  * @param {String} [path]
- * @param {Number} val
+ * @param {Array} val
  * @api public
  */
 
@@ -486,7 +508,7 @@ Query.prototype.slice = function() {
  * @memberOf Query
  * @instance
  * @param {String} [path]
- * @param {Number} val
+ * @param {Array} val
  * @api public
  */
 
@@ -626,7 +648,7 @@ Query.prototype.mod = function() {
  * @memberOf Query
  * @instance
  * @param {String} [path]
- * @param {Number} val
+ * @param {Boolean} val
  * @return {Query} this
  * @see $exists http://docs.mongodb.org/manual/reference/operator/exists/
  * @api public
@@ -700,28 +722,6 @@ Query.prototype.mod = function() {
  * @api public
  */
 
-/**
- * Specifies a `$slice` projection for an array.
- *
- * ####Example
- *
- *     query.slice('comments', 5)
- *     query.slice('comments', -5)
- *     query.slice('comments', [10, 5])
- *     query.where('comments').slice(5)
- *     query.where('comments').slice([-10, 5])
- *
- * @method slice
- * @memberOf Query
- * @instance
- * @param {String} [path]
- * @param {Number} val number/range of elements to slice
- * @return {Query} this
- * @see mongodb http://www.mongodb.org/display/DOCS/Retrieving+a+Subset+of+Fields#RetrievingaSubsetofFields-RetrievingaSubrangeofArrayElements
- * @see $slice http://docs.mongodb.org/manual/reference/projection/slice/#prj._S_slice
- * @api public
- */
-
 /**
  * Specifies the maximum number of documents the query will return.
  *

From 48dcd05196393a465986b7661c30a065020b75bd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 15 Oct 2020 13:44:06 -0400
Subject: [PATCH 1271/2348] chore: update opencollective sponsors

---
 index.pug | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/index.pug b/index.pug
index a75cbd45af2..7802f03e5d9 100644
--- a/index.pug
+++ b/index.pug
@@ -298,9 +298,6 @@ html(lang='en')
               <a rel="sponsored" href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
                 <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://casinomatcher.com/ca/">
-                <img class="sponsor" src="https://images.opencollective.com/casinomatcher-com/31fbd0d/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://netticasinohex.com/kasinot/">
                 <img class="sponsor" src="https://images.opencollective.com/netticasinohex-com/71d7417/logo/256.png" style="height: 100px">
               </a>
@@ -355,7 +352,7 @@ html(lang='en')
               <a rel="sponsored" href="https://onlinecasinoguide.co.nz/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinoguide-co-nz/b16a388/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://casino-academia.com/">
+              <a rel="sponsored" href="https://casino-academia.jp/">
                 <img class="sponsor" src="https://images.opencollective.com/casinoacademia/90fc970/logo/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://nettikasinolista.com/">

From 3f2f8c149bff28ece6b960116b2c5c19e439c42e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 15 Oct 2020 14:04:26 -0400
Subject: [PATCH 1272/2348] fix(schema): handle merging schemas from separate
 Mongoose module instances when schema has a virtual

Fix #9471
---
 lib/schema.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 809d80463d7..011fc352600 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -477,7 +477,7 @@ Schema.prototype.add = function add(obj, prefix) {
     if (key === '_id' && obj[key] === false) {
       continue;
     }
-    if (obj[key] instanceof VirtualType) {
+    if (obj[key] instanceof VirtualType || obj[key].constructor.name === 'VirtualType') {
       this.virtual(obj[key]);
       continue;
     }
@@ -1678,7 +1678,7 @@ Schema.prototype.indexes = function() {
  */
 
 Schema.prototype.virtual = function(name, options) {
-  if (name instanceof VirtualType) {
+  if (name instanceof VirtualType || (name != null && name.constructor.name === 'VirtualType')) {
     return this.virtual(name.path, name.options);
   }
 

From e0867ab0d3e9aa7cd6a5f1cdfb874cb12bda93ef Mon Sep 17 00:00:00 2001
From: Tareq Dayya <41693150+tareqdayya@users.noreply.github.com>
Date: Sun, 18 Oct 2020 14:49:50 +0300
Subject: [PATCH 1273/2348] Update connections.pug

Make it clear that mongoose.connection.on('error') does not fire once connection is lost any time after the initial connection. The text seems to suggest, to me at least, that it's the code to use to listen to drops in connection after the initial connection.
Only 3 Lines were added: 148-150.
---
 docs/connections.pug | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/docs/connections.pug b/docs/connections.pug
index 933c8f1812f..ae9c93972ad 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -145,6 +145,10 @@ block content
     });
     ```
 
+    Note that the `error` event in the code above does not fire when mongoose loses 
+    connection after the initial connection was established. You can listen to the
+    `disconnected` event for that purpose.
+
     <h3 id="options"><a href="#options">Options</a></h3>
 
     The `connect` method also accepts an `options` object which will be passed

From d06388ff3168f72b178cb08568f2fdabd23306f3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 22 Oct 2020 10:45:19 -0400
Subject: [PATCH 1274/2348] test(query): repro #9479

---
 test/model.query.casting.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index ad45fbb9889..9ed7947ca1b 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -7,6 +7,7 @@
 const start = require('./common');
 
 const assert = require('assert');
+const co = require('co');
 const random = require('../lib/utils').random;
 
 const mongoose = start.mongoose;
@@ -900,6 +901,22 @@ describe('model query casting', function() {
         });
       }
     });
+
+    it('casts $nor within $elemMatch (gh-9479)', function() {
+      const Test = db.model('Test', Schema({
+        arr: [{ x: Number, y: Number }]
+      }));
+
+      return co(function*() {
+        const _doc = yield Test.create({ arr: [{ x: 1 }, { y: 3 }, { x: 2 }] });
+
+        const doc = yield Test.findOne({
+          arr: { $elemMatch: { $nor: [{ x: 1 }, { y: 3 }] }  }
+        });
+
+        assert.equal(_doc._id.toString(), doc._id.toString());
+      });
+    });
   });
 
   it('works with $all (gh-3394)', function(done) {

From 39e54ef657a3d2dffe183bb3c490fe7fa4bbc0c4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 22 Oct 2020 10:46:14 -0400
Subject: [PATCH 1275/2348] fix(query): cast $nor within $elemMatch

Fix #9479
---
 lib/schema/array.js              | 26 ++++++++++++++++----------
 test/model.query.casting.test.js |  2 +-
 2 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 044cc3af233..828eb1be09a 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -537,18 +537,24 @@ handle.$all = cast$all;
 handle.$options = String;
 handle.$elemMatch = cast$elemMatch;
 handle.$geoIntersects = geospatial.cast$geoIntersects;
-handle.$or = handle.$and = function(val) {
-  if (!Array.isArray(val)) {
-    throw new TypeError('conditional $or/$and require array');
-  }
+handle.$or = createLogicalQueryOperatorHandler('$or');
+handle.$and = createLogicalQueryOperatorHandler('$and');
+handle.$nor = createLogicalQueryOperatorHandler('$nor');
+
+function createLogicalQueryOperatorHandler(op) {
+  return function logicalQueryOperatorHandler(val) {
+    if (!Array.isArray(val)) {
+      throw new TypeError('conditional ' + op + ' requires an array');
+    }
 
-  const ret = [];
-  for (const obj of val) {
-    ret.push(cast(this.casterConstructor.schema, obj));
-  }
+    const ret = [];
+    for (const obj of val) {
+      ret.push(cast(this.casterConstructor.schema, obj));
+    }
 
-  return ret;
-};
+    return ret;
+  };
+}
 
 handle.$near =
 handle.$nearSphere = geospatial.cast$near;
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index 9ed7947ca1b..357c7c52a9f 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -911,7 +911,7 @@ describe('model query casting', function() {
         const _doc = yield Test.create({ arr: [{ x: 1 }, { y: 3 }, { x: 2 }] });
 
         const doc = yield Test.findOne({
-          arr: { $elemMatch: { $nor: [{ x: 1 }, { y: 3 }] }  }
+          arr: { $elemMatch: { $nor: [{ x: 1 }, { y: 3 }] } }
         });
 
         assert.equal(_doc._id.toString(), doc._id.toString());

From 86aace14dbd82a01ec996a6a4d1b4f6205484233 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 22 Oct 2020 11:05:30 -0400
Subject: [PATCH 1276/2348] fix(schema): handle objects without a constructor
 property re: #9471

---
 lib/schema.js                   |  2 +-
 test/object.create.null.test.js | 12 ++++++------
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 011fc352600..2abd0a01a28 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -477,7 +477,7 @@ Schema.prototype.add = function add(obj, prefix) {
     if (key === '_id' && obj[key] === false) {
       continue;
     }
-    if (obj[key] instanceof VirtualType || obj[key].constructor.name === 'VirtualType') {
+    if (obj[key] instanceof VirtualType || get(obj[key], 'constructor.name', null) === 'VirtualType') {
       this.virtual(obj[key]);
       continue;
     }
diff --git a/test/object.create.null.test.js b/test/object.create.null.test.js
index 155014c54d2..0443cfc8dcd 100644
--- a/test/object.create.null.test.js
+++ b/test/object.create.null.test.js
@@ -118,25 +118,25 @@ describe('is compatible with object created using Object.create(null) (gh-1484)'
     o.nested = Object.create(null);
     o.nested.n = Number;
 
-    assert.doesNotThrow(function() {
+    void function() {
       new Schema(o);
-    });
+    }();
 
-    assert.doesNotThrow(function() {
+    void function() {
       const s = new Schema;
       const o = Object.create(null);
       o.yay = Number;
       s.path('works', o);
-    });
+    }();
 
-    assert.doesNotThrow(function() {
+    void function() {
       const s = new Schema;
       let o = Object.create(null);
       o = {};
       o.name = String;
       const x = { type: [o] };
       s.path('works', x);
-    });
+    }();
 
     done();
   });

From 88681020db0cadd88f39799a7d56562dd49eb422 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 22 Oct 2020 12:28:36 -0400
Subject: [PATCH 1277/2348] feat(connection): add bufferTimeoutMS option that
 configures how long Mongoose will allow commands to buffer

Fix #9469
---
 docs/connections.pug                          |  4 +-
 docs/faq.pug                                  | 24 ++++----
 docs/guide.pug                                | 11 ++++
 lib/collection.js                             | 40 +++++++++++++
 lib/connection.js                             |  1 +
 lib/drivers/node-mongodb-native/collection.js | 59 +++++++++++++++----
 lib/index.js                                  |  1 +
 lib/validoptions.js                           |  1 +
 8 files changed, 115 insertions(+), 26 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 933c8f1812f..6614b745575 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -158,8 +158,8 @@ block content
     Mongoose passes options to the driver without modification, modulo a few
     exceptions that are explained below.
 
-    * `bufferCommands`    - This is a mongoose-specific option (not passed to the MongoDB driver) that disables [mongoose's buffering mechanism](http://mongoosejs.com/docs/faq.html#callback_never_executes)
-    * `user`/`pass`       - The username and password for authentication. These options are mongoose-specific, they are equivalent to the MongoDB driver's `auth.user` and `auth.password` options.
+    * `bufferCommands`    - This is a mongoose-specific option (not passed to the MongoDB driver) that disables [Mongoose's buffering mechanism](http://mongoosejs.com/docs/faq.html#callback_never_executes)
+    * `user`/`pass`       - The username and password for authentication. These options are Mongoose-specific, they are equivalent to the MongoDB driver's `auth.user` and `auth.password` options.
     * `autoIndex`         - By default, mongoose will automatically build indexes defined in your schema when it connects. This is great for development, but not ideal for large production deployments, because index builds can cause performance degradation. If you set `autoIndex` to false, mongoose will not automatically build indexes for **any** model associated with this connection.
     * `dbName`            - Specifies which database to connect to and overrides any database specified in the connection string. This is useful if you are unable to specify a default database in the connection string like with [some `mongodb+srv` syntax connections](https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626).
 
diff --git a/docs/faq.pug b/docs/faq.pug
index 37269ea197d..9ba681b04f5 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -311,26 +311,26 @@ block content
     <a href="#callback_never_executes">**Q**</a>. My `save()` callback never executes. What am I doing wrong?
 
     **A**. All `collection` actions (insert, remove, queries, etc.) are queued
-    until the `connection` opens. It is likely that an error occurred while
-    attempting to connect. Try adding an error handler to your connection.
+    until Mongoose successfully connects to MongoDB. It is likely you haven't called Mongoose's
+    `connect()` or `createConnection()` function yet.
 
-    ```javascript
-    // if connecting on the default mongoose connection
-    mongoose.connect(..);
-    mongoose.connection.on('error', handleError);
-
-    // if connecting on a separate connection
-    const conn = mongoose.createConnection(..);
-    conn.on('error', handleError);
-    ```
+    In Mongoose 5.11, there is a `bufferTimeoutMS` option (set to 10000 by default) that configures how long
+    Mongoose will allow an operation to stay buffered before throwing an error.
 
-    If you want to opt out of mongoose's buffering mechanism across your entire
+    If you want to opt out of Mongoose's buffering mechanism across your entire
     application, set the global `bufferCommands` option to false:
 
     ```javascript
     mongoose.set('bufferCommands', false);
     ```
 
+    Instead of opting out of Mongoose's buffering mechanism, you may want to instead reduce `bufferTimeoutMS`
+    to make Mongoose only buffer for a short time.
+
+    ```javascript
+    // If an operation is buffered for more than 500ms, throw an error.
+    mongoose.set('bufferTimeoutMS', 500);
+    ```
 
     <hr id="creating_connections" />
 
diff --git a/docs/guide.pug b/docs/guide.pug
index c539e4fa883..5a4df7761f9 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -418,6 +418,7 @@ block content
     - [autoIndex](#autoIndex)
     - [autoCreate](#autoCreate)
     - [bufferCommands](#bufferCommands)
+    - [bufferTimeoutMS](#bufferTimeoutMS)
     - [capped](#capped)
     - [collection](#collection)
     - [id](#id)
@@ -503,6 +504,16 @@ block content
     const schema = new Schema({..}, { bufferCommands: false });
     ```
 
+    <h3 id="bufferTimeoutMS"><a href="#bufferTimeoutMS">option: bufferTimeoutMS</a></h3>
+
+    If `bufferCommands` is on, this option sets the maximum amount of time Mongoose buffering will wait before
+    throwing an error. If not specified, Mongoose will use 10000 (10 seconds).
+
+    ```javascript
+    // If an operation is buffered for more than 1 second, throw an error.
+    const schema = new Schema({..}, { bufferTimeoutMS: 1000 });
+    ```
+
     <h3 id="capped"><a href="#capped">option: capped</a></h3>
 
     Mongoose supports MongoDBs [capped](http://www.mongodb.org/display/DOCS/Capped+Collections)
diff --git a/lib/collection.js b/lib/collection.js
index 97f5bb3238e..076f88faaca 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -108,6 +108,23 @@ Collection.prototype.addQueue = function(name, args) {
   return this;
 };
 
+/**
+ * Removes a queued method
+ *
+ * @param {String} name name of the method to queue
+ * @param {Array} args arguments to pass to the method when executed
+ * @api private
+ */
+
+Collection.prototype.removeQueue = function(name, args) {
+  const index = this.queue.findIndex(v => v[0] === name && v[1] === args);
+  if (index === -1) {
+    return false;
+  }
+  this.queue.splice(index, 1);
+  return true;
+};
+
 /**
  * Executes all queued methods and clears the queue.
  *
@@ -281,6 +298,29 @@ Collection.prototype._shouldBufferCommands = function _shouldBufferCommands() {
   return true;
 };
 
+/*!
+ * ignore
+ */
+
+Collection.prototype._getBufferTimeoutMS = function _getBufferTimeoutMS() {
+  const conn = this.conn;
+  const opts = this.opts;
+
+  if (opts.bufferTimeoutMS != null) {
+    return opts.bufferTimeoutMS;
+  }
+  if (opts && opts.schemaUserProvidedOptions != null && opts.schemaUserProvidedOptions.bufferTimeoutMS != null) {
+    return opts.schemaUserProvidedOptions.bufferTimeoutMS;
+  }
+  if (conn.config.bufferTimeoutMS != null) {
+    return conn.config.bufferTimeoutMS;
+  }
+  if (conn.base != null && conn.base.get('bufferTimeoutMS') != null) {
+    return conn.base.get('bufferTimeoutMS');
+  }
+  return 10000;
+};
+
 /*!
  * Module exports.
  */
diff --git a/lib/connection.js b/lib/connection.js
index dcf616e6e3a..d44d045ac3b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -611,6 +611,7 @@ Connection.prototype.onOpen = function() {
  * @param {String} uri The URI to connect with.
  * @param {Object} [options] Passed on to http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect
  * @param {Boolean} [options.bufferCommands=true] Mongoose specific option. Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection.
+ * @param {Number} [options.bufferTimeoutMS=true] Mongoose specific option. If `bufferCommands` is true, Mongoose will throw an error after `bufferTimeoutMS` if the operation is still buffered.
  * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index d660c7de51c..62f18bec2a2 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -144,21 +144,53 @@ function iter(i) {
       if (syncCollectionMethods[i]) {
         throw new Error('Collection method ' + i + ' is synchronous');
       }
-      if (typeof lastArg === 'function') {
-        this.addQueue(i, args);
-        return;
-      }
 
       this.conn.emit('buffer', { method: i, args: args });
 
-      return new this.Promise((resolve, reject) => {
-        this.addQueue(i, [].concat(args).concat([(err, res) => {
-          if (err != null) {
-            return reject(err);
+      let callback;
+      let _args;
+      let promise = null;
+      let timeout = null;
+      if (typeof lastArg === 'function') {
+        callback = function collectionOperationCallback() {
+          if (timeout != null) {
+            clearTimeout(timeout);
           }
-          resolve(res);
-        }]));
-      });
+          return lastArg.apply(this, arguments);
+        };
+        _args = args.slice(0, args.length - 1).concat([callback]);
+      } else {
+        promise = new this.Promise((resolve, reject) => {
+          callback = function collectionOperationCallback(err, res) {
+            if (timeout != null) {
+              clearTimeout(timeout);
+            }
+            if (err != null) {
+              return reject(err);
+            }
+            resolve(res);
+          };
+          _args = args.concat([callback]);
+          this.addQueue(i, _args);
+        });
+      }
+
+      const bufferTimeoutMS = this._getBufferTimeoutMS();
+      timeout = setTimeout(() => {
+        const removed = this.removeQueue(i, _args);
+        if (removed) {
+          const message = 'Operation `' + this.name + '.' + i + '()` buffering timed out after ' +
+            bufferTimeoutMS + 'ms';
+          callback(new MongooseError(message));
+        }
+      }, bufferTimeoutMS);
+
+      if (typeof lastArg === 'function') {
+        this.addQueue(i, _args);
+        return;
+      }
+
+      return promise;
     }
 
     if (debug) {
@@ -174,7 +206,10 @@ function iter(i) {
 
     try {
       if (collection == null) {
-        throw new MongooseError('Cannot call `' + this.name + '.' + i + '()` before initial connection is complete if `bufferCommands = false`. Make sure you `await mongoose.connect()` if you have `bufferCommands = false`.');
+        const message = 'Cannot call `' + this.name + '.' + i + '()` before initial connection ' +
+          'is complete if `bufferCommands = false`. Make sure you `await mongoose.connect()` if ' +
+          'you have `bufferCommands = false`.';
+        throw new MongooseError(message);
       }
 
       return collection[i].apply(collection, args);
diff --git a/lib/index.js b/lib/index.js
index fccb625bd62..5769cc59970 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -310,6 +310,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {String} uri(s)
  * @param {Object} [options] passed down to the [MongoDB driver's `connect()` function](http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html), except for 4 mongoose-specific options explained below.
  * @param {Boolean} [options.bufferCommands=true] Mongoose specific option. Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection.
+ * @param {Number} [options.bufferTimeoutMS=true] Mongoose specific option. If `bufferCommands` is true, Mongoose will throw an error after `bufferTimeoutMS` if the operation is still buffered.
  * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 510d7e277e7..3eb19550e6f 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -11,6 +11,7 @@ const VALID_OPTIONS = Object.freeze([
   'autoCreate',
   'autoIndex',
   'bufferCommands',
+  'bufferTimeoutMS',
   'cloneSchemas',
   'debug',
   'maxTimeMS',

From f52c589709e73107a84d22b8c8c918f04b1ef88e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 23 Oct 2020 08:08:19 +0200
Subject: [PATCH 1278/2348] test(connection): repro #9496

---
 test/connection.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index 03c534098c2..41e065b0231 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1210,4 +1210,20 @@ describe('connections:', function() {
       assert.ok(res);
     });
   });
+
+  it('connection.then(...) resolves to a connection instance (gh-9496)', function() {
+    return co(function *() {
+      const m = new mongoose.Mongoose;
+
+      m.connect('mongodb://localhost:27017/test_gh9496', {
+        useNewUrlParser: true,
+        useUnifiedTopology: true
+      });
+      const conn = yield m.connection;
+
+      assert.ok(conn instanceof m.Connection);
+      assert.ok(conn);
+    });
+  });
+
 });

From 82311de9da270e9ff7fb94cfb43b7700a449b3c2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 23 Oct 2020 08:08:53 +0200
Subject: [PATCH 1279/2348] fix(connection): make connection.then(...) resolve
 to a connection instance re: #9496

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index dcf616e6e3a..6e70a822308 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -811,7 +811,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
       throw err;
     });
   this.then = function(resolve, reject) {
-    return this.$initialConnection.then(resolve, reject);
+    return this.$initialConnection.then(() => resolve(_this), reject);
   };
   this.catch = function(reject) {
     return this.$initialConnection.catch(reject);

From 394186239e1b778812fa9bb973d45fa05ddd514c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Oct 2020 11:59:27 -0400
Subject: [PATCH 1280/2348] fix(aggregate): when using $search with
 discriminators, add `$match` as the 2nd stage in pipeline rather than 1st

Fix #9487
---
 lib/aggregate.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index 6dc43926f86..f562e571044 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -1139,6 +1139,14 @@ function prepareDiscriminatorPipeline(aggregate) {
       originalPipeline[0].$geoNear.query =
           originalPipeline[0].$geoNear.query || {};
       originalPipeline[0].$geoNear.query[discriminatorKey] = discriminatorValue;
+    } else if (originalPipeline[0] && originalPipeline[0].$search) {
+      if (originalPipeline[1] && originalPipeline[1].$match != null) {
+        originalPipeline[1].$match[discriminatorKey] = originalPipeline[1].$match[discriminatorKey] || discriminatorValue;
+      } else {
+        const match = {};
+        match[discriminatorKey] = discriminatorValue;
+        originalPipeline.splice(1, 0, { $match: match });
+      }
     } else {
       const match = {};
       match[discriminatorKey] = discriminatorValue;

From 1264d7e6c09b6b868dec78bd35cc8db440f562b7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Oct 2020 12:51:46 -0400
Subject: [PATCH 1281/2348] chore: release 5.10.10

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index e1b569dca63..9086e2c746b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.10.10 / 2020-10-23
+====================
+ * fix(schema): handle merging schemas from separate Mongoose module instances when schema has a virtual #9471
+ * fix(connection): make connection.then(...) resolve to a connection instance #9497 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(aggregate): when using $search with discriminators, add `$match` as the 2nd stage in pipeline rather than 1st #9487
+ * fix(query): cast $nor within $elemMatch #9479
+ * docs(connection): add note about 'error' event versus 'disconnected' event #9488 [tareqdayya](https://github.com/tareqdayya)
+
 5.10.9 / 2020-10-09
 ===================
  * fix(update): strip out unused array filters to avoid "filter was not used in the update" error #9468
diff --git a/package.json b/package.json
index a9eae6d3867..763a381dfec 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.9",
+  "version": "5.10.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a8970ead786a6cc5c749497499b4e84cf303c367 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Oct 2020 17:15:19 -0400
Subject: [PATCH 1282/2348] test(document): repro #9427

---
 test/document.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 33074529a94..7aebf8ce278 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9490,4 +9490,28 @@ describe('document', function() {
 
     assert.deepEqual(testUser.toObject().preferences.notifications, { email: true, push: false });
   });
+
+  it('avoids overwriting array subdocument when setting dotted path that is not selected (gh-9427)', function() {
+    const Test = db.model('Test', Schema({
+      arr: [{ _id: false, val: Number }],
+      name: String,
+      age: Number
+    }));
+
+    return co(function*() {
+      let doc = yield Test.create({
+        name: 'Test',
+        arr: [{ val: 1 }, { val: 2 }],
+        age: 30
+      });
+
+      doc = yield Test.findById(doc._id).select('name');
+      doc.set('arr.0.val', 2);
+      yield doc.save();
+
+      const fromDb = yield Test.findById(doc._id);
+      assert.deepEqual(fromDb.toObject().arr, [{ val: 2 }, { val: 2 }]);
+    });
+
+  });
 });

From 800e233ef6f168e5ba7768f6d665cbc9336957d3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Oct 2020 17:15:32 -0400
Subject: [PATCH 1283/2348] fix(document): avoid overwriting array subdocument
 when setting dotted path that isn't selected

Fix #9427
---
 lib/types/embedded.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index d0cfdcfc73a..18a977847ae 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -100,7 +100,8 @@ EmbeddedDocument.prototype.markModified = function(path) {
     return;
   }
 
-  if (this.isNew) {
+  const pathToCheck = this.__parentArray.$path() + '.0.' + path;
+  if (this.isNew && this.ownerDocument().isSelected(pathToCheck)) {
     // Mark the WHOLE parent array as modified
     // if this is a new document (i.e., we are initializing
     // a document),

From 6a1fa05bf45a5e5719e8852f8c220a59b97f1ee1 Mon Sep 17 00:00:00 2001
From: Reece Adamson <radamson@mitre.org>
Date: Fri, 23 Oct 2020 16:57:55 -0400
Subject: [PATCH 1284/2348] update docs

---
 CONTRIBUTING.md | 1 +
 lib/model.js    | 2 ++
 lib/query.js    | 1 +
 3 files changed, 4 insertions(+)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index d6f6988784c..6be7da984bd 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -51,6 +51,7 @@ To contribute to the [guide](http://mongoosejs.com/docs/guide.html) or [quick st
 
 If you'd like to preview your documentation changes, first commit your changes to your local master branch, then execute:
 
+* `npm install`
 * `make docclean`
 * `make gendocs`
 * `node static.js`
diff --git a/lib/model.js b/lib/model.js
index 0c1e8ccb701..69979619560 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2369,6 +2369,7 @@ Model.$where = function $where() {
  *
  * - `new`: bool - if true, return the modified document rather than the original. defaults to false (changed in 4.0)
  * - `upsert`: bool - creates the object if it doesn't exist. defaults to false.
+ * - `overwrite`: bool - if true, replace the entire document.
  * - `fields`: {Object|String} - Field selection. Equivalent to `.select(fields).findOneAndUpdate()`
  * - `maxTimeMS`: puts a time limit on the query - requires mongodb >= 2.6.0
  * - `sort`: if multiple docs are found by the conditions, sets the sort order to choose which doc to update
@@ -2430,6 +2431,7 @@ Model.$where = function $where() {
  * @param {Boolean} [options.timestamps=null] If set to `false` and [schema-level timestamps](/docs/guide.html#timestamps) are enabled, skip timestamps for this update. Note that this allows you to overwrite timestamps. Does nothing if schema-level timestamps are not set.
  * @param {Boolean} [options.returnOriginal=null] An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
  * @param {Boolean} [options.overwrite=false] By default, if you don't include any [update operators](https://docs.mongodb.com/manual/reference/operator/update/) in `update`, Mongoose will wrap `update` in `$set` for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding `$set`. An alternative to this would be using [Model.findOneAndReplace(conditions, update, options, callback)](https://mongoosejs.com/docs/api/model.html#model_Model.findOneAndReplace).
+ * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
  * @param {Object|String|Array<String>} [options.projection=null] optional fields to return, see [`Query.prototype.select()`](#query_Query-select)
  * @param {Function} [callback]
  * @return {Query}
diff --git a/lib/query.js b/lib/query.js
index d4a41397c4e..2fd695a2aeb 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1298,6 +1298,7 @@ Query.prototype.getOptions = function() {
  * - [timestamps](https://mongoosejs.com/docs/guide.html#timestamps): If `timestamps` is set in the schema, set this option to `false` to skip timestamps for that particular update. Has no effect if `timestamps` is not enabled in the schema options.
  * - omitUndefined: delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
  * - overwriteDiscriminatorKey: allow setting the discriminator key in the update. Will use the correct discriminator schema if the update changes the discriminator key.
+ * - overwrite: replace the entire document
  *
  * The following options are only for `find()`, `findOne()`, `findById()`, `findOneAndUpdate()`, and `findByIdAndUpdate()`:
  *

From d7aaa5568330e2dcadde7ae6847bff1522f3ae4e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Oct 2020 18:27:36 -0400
Subject: [PATCH 1285/2348] chore(index.d.ts): add several more query methods
 to TypeScript definitions re: #8108

---
 index.d.ts   | 136 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 lib/query.js |  35 +------------
 2 files changed, 136 insertions(+), 35 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c77c04aa510..f2ec4ac637f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -635,6 +635,7 @@ declare module "mongoose" {
     session?: mongodb.ClientSession;
     explain?: any;
     multi?: boolean;
+    strict: boolean | string;
   }
 
   interface SaveOptions {
@@ -936,6 +937,9 @@ declare module "mongoose" {
     /** Specifies the batchSize option. */
     batchSize(val: number): this;
 
+    /** Adds a collation to this op (MongoDB 3.4 and up) */
+    collation(value: mongodb.CollationDocument): this;
+
     /** Specifies the `comment` option. */
     comment(val: string): this;
 
@@ -947,6 +951,20 @@ declare module "mongoose" {
     countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType>;
     countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
 
+    /**
+     * Declare and/or execute this query as a `deleteMany()` operation. Works like
+     * remove, except it deletes _every_ document that matches `filter` in the
+     * collection, regardless of the value of `single`.
+     */
+    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+
+    /**
+     * Declare and/or execute this query as a `deleteOne()` operation. Works like
+     * remove, except it deletes at most one document regardless of the `single`
+     * option.
+     */
+    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType>;
 
@@ -954,6 +972,13 @@ declare module "mongoose" {
     elemMatch(val: Function | any): this;
     elemMatch(path: string, val: Function | any): this;
 
+    /**
+     * Gets/sets the error flag on this query. If this flag is not null or
+     * undefined, the `exec()` promise will reject without executing.
+     */
+    error(): Error | null;
+    error(val: Error | null): this;
+
     /** Specifies the complementary comparison value for paths specified with `where()` */
     equals(val: any): this;
 
@@ -964,10 +989,21 @@ declare module "mongoose" {
     exists(val: boolean): this;
     exists(path: string, val: boolean): this;
 
+    /**
+     * Sets the [`explain` option](https://docs.mongodb.com/manual/reference/method/cursor.explain/),
+     * which makes this query return detailed execution stats instead of the actual
+     * query result. This method is useful for determining what index your queries
+     * use.
+     */
+    explain(verbose?: string): this;
+
     /** Creates a `find` query: gets a list of documents that match `filter`. */
     find(callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
     find(filter: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: Error | null, count: number) => void): Query<Array<DocType>, DocType>;
+
+    /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: Error | null, count: number) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
@@ -984,6 +1020,25 @@ declare module "mongoose" {
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
+    /**
+     * For update operations, returns the value of a path in the update's `$set`.
+     * Useful for writing getters/setters that can work with both update operations
+     * and `save()`.
+     */
+    get(path: string): any;
+
+    /** Returns the current query filter (also known as conditions) as a POJO. */
+    getFilter(): FilterQuery<DocType>;
+
+    /** Gets query options. */
+    getOptions(): QueryOptions;
+
+    /** Returns the current query filter. Equivalent to `getFilter()`. */
+    getQuery(): FilterQuery<DocType>;
+
+    /** Returns the current update operations as a JSON object. */
+    getUpdate(): UpdateQuery<DocType> | null;
+
     /** Specifies a `$gt` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     gt(val: number): this;
     gt(path: string, val: number): this;
@@ -999,6 +1054,12 @@ declare module "mongoose" {
     in(val: Array<any>): this;
     in(path: string, val: Array<any>): this;
 
+    /** Requests acknowledgement that this operation has been persisted to MongoDB's on-disk journal. */
+    j(val: boolean | null): this;
+
+    /** Sets the lean option. */
+    lean(val?: boolean | any): this;
+
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
 
@@ -1017,10 +1078,26 @@ declare module "mongoose" {
     /** Specifies the maxScan option. */
     maxScan(val: number): this;
 
+    /**
+     * Sets the [maxTimeMS](https://docs.mongodb.com/manual/reference/method/cursor.maxTimeMS/)
+     * option. This will tell the MongoDB server to abort if the query or write op
+     * has been running for more than `ms` milliseconds.
+     */
+    maxTimeMS(ms: number): this;
+
+    /** Merges another Query or conditions object into this one. */
+    merge(source: Query<any, any>): this;
+
     /** Specifies a `$mod` condition, filters documents for documents whose `path` property is a number that is equal to `remainder` modulo `divisor`. */
     mod(val: Array<number>): this;
     mod(path: string, val: Array<number>): this;
 
+    /**
+     * Getter/setter around the current mongoose-specific options for this query
+     * Below are the current Mongoose-specific options.
+     */
+    mongooseOptions(val?: Pick<QueryOptions, "populate" | "lean" | "omitUndefined" | "strict" | "useFindAndModify">): Pick<QueryOptions, "populate" | "lean" | "omitUndefined" | "strict" | "useFindAndModify">;
+
     /** Specifies a `$ne` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     ne(val: any): this;
     ne(path: string, val: any);
@@ -1035,10 +1112,51 @@ declare module "mongoose" {
     /** Specifies arguments for an `$or` condition. */
     or(array: Array<FilterQuery<DocType>>): this;
 
+    /** Get/set the current projection (AKA fields). Pass `null` to remove the current projection. */
+    projection(fields?: any | null): any;
+
+    /** Determines the MongoDB nodes from which to read. */
+    read(pref: string | mongodb.ReadPreferenceMode, tags?: any[]): this;
+
+    /** Sets the readConcern option for the query. */
+    readConcern(level: string): this;
+
     /** Specifies a `$regex` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     regex(val: string | RegExp): this;
     regex(path: string, val: string | RegExp): this;
 
+    /**
+     * Declare and/or execute this query as a remove() operation. `remove()` is
+     * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
+     * or [`deleteMany()`](#query_Query-deleteMany) instead. 
+     */
+    remove(filter?: FilterQuery<DocType>, callback?: (err: Error | null, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType>;
+
+    /** Specifies which document fields to include or exclude (also known as the query "projection") */
+    select(arg: string | any): this;
+
+    /**
+     * Sets the [MongoDB session](https://docs.mongodb.com/manual/reference/server-sessions/)
+     * associated with this query. Sessions are how you mark a query as part of a
+     * [transaction](/docs/transactions.html).
+     */
+    session(session: mongodb.ClientSession | null): this;
+
+    /**
+     * Adds a `$set` to this query's update without changing the operation.
+     * This is useful for query middleware so you can add an update regardless
+     * of whether you use `updateOne()`, `updateMany()`, `findOneAndUpdate()`, etc. 
+     */
+    set(path: string, value: any): this;
+
+    /** Sets query options. Some options only make sense for certain operations. */
+    setOptions(options: QueryOptions, overwrite: boolean): this;
+
+    /** Sets the query conditions to the provided JSON object. */
+    setQuery(val: FilterQuery<DocType> | null): void;
+
+    setUpdate(update: UpdateQuery<DocType>): void;
+
     /** Specifies an `$size` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     size(val: number): this;
     size(path: string, val: number): this;
@@ -1053,14 +1171,30 @@ declare module "mongoose" {
     /** Specifies this query as a `snapshot` query. */
     snapshot(val?: boolean): this;
 
+    /** Sets the sort order. If an object is passed, values allowed are `asc`, `desc`, `ascending`, `descending`, `1`, and `-1`. */
+    sort(arg: string | any): this;
+
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
     toConstructor(): new (filter?: FilterQuery<DocType>, options?: QueryOptions) => Query<ResultType, DocType>;
 
+    /**
+     * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
+     * that must acknowledge this write before this write is considered successful.
+     */
+    w(val: string | number | null): this;
+
     /** Specifies a path for use with chaining. */
     where(path: string, val?: any): this;
 
     /** Defines a `$within` or `$geoWithin` argument for geo-spatial queries. */
     within(val?: any): this;
+
+    /**
+     * If [`w > 1`](/docs/api.html#query_Query-w), the maximum amount of time to
+     * wait for this write to propagate through the replica set before this
+     * operation fails. The default is `0`, which means no timeout.
+     */
+    wtimeout(ms: number): this;
   }
 
   export type FilterQuery<T> = {
diff --git a/lib/query.js b/lib/query.js
index f84365b8dda..e709049f5ab 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1427,7 +1427,7 @@ Query.prototype.maxTimeMS = function(ms) {
 };
 
 /**
- * Returns the current query filter (also known as conditions) as a POJO.
+ * Returns the current query filter (also known as conditions) as a [POJO](https://masteringjs.io/tutorials/fundamentals/pojo).
  *
  * ####Example:
  *
@@ -1686,39 +1686,6 @@ Query.prototype.lean = function(v) {
   return this;
 };
 
-/**
- * Returns an object containing the Mongoose-specific options for this query,
- * including `lean` and `populate`.
- *
- * Mongoose-specific options are different from normal options (`sort`, `limit`, etc.)
- * because they are **not** sent to the MongoDB server.
- *
- * ####Example:
- *
- *     const q = new Query();
- *     q.mongooseOptions().lean; // undefined
- *
- *     q.lean();
- *     q.mongooseOptions().lean; // true
- *
- * This function is useful for writing [query middleware](/docs/middleware.html).
- * Below is a full list of properties the return value from this function may have:
- *
- * - `populate`
- * - `lean`
- * - `omitUndefined`
- * - `strict`
- * - `nearSphere`
- * - `useFindAndModify`
- *
- * @return {Object} Mongoose-specific options
- * @param public
- */
-
-Query.prototype.mongooseOptions = function() {
-  return this._mongooseOptions;
-};
-
 /**
  * Adds a `$set` to this query's update without changing the operation.
  * This is useful for query middleware so you can add an update regardless

From 31b762194f151b27c457b61b01bba60b0e6e8acd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 12:00:16 -0400
Subject: [PATCH 1286/2348] chore: add remaining query and querycursor methods
 to TypeScript definitions

Re: #8108
---
 index.d.ts                     | 146 ++++++++++++++++++++++++++++++++-
 test/typescript/main.test.js   |   8 ++
 test/typescript/queries.ts     |   1 +
 test/typescript/querycursor.ts |  13 +++
 4 files changed, 167 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/querycursor.ts

diff --git a/index.d.ts b/index.d.ts
index f2ec4ac637f..36c30999d70 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2,6 +2,7 @@ declare module "mongoose" {
   import events = require('events');
   import mongodb = require('mongodb');
   import mongoose = require('mongoose');
+  import stream = require('stream');
 
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
   export function connect(uri: string, options: ConnectOptions, callback: (err: Error) => void): void;
@@ -635,7 +636,7 @@ declare module "mongoose" {
     session?: mongodb.ClientSession;
     explain?: any;
     multi?: boolean;
-    strict: boolean | string;
+    strict?: boolean | string;
   }
 
   interface SaveOptions {
@@ -937,6 +938,23 @@ declare module "mongoose" {
     /** Specifies the batchSize option. */
     batchSize(val: number): this;
 
+    /** Specifies a `$box` condition */
+    box(val: any): this;
+    box(lower: number[], upper: number[]): this;
+
+    cast(model: Model<any> | null, obj: any): UpdateQuery<DocType>;
+
+    /**
+     * Executes the query returning a `Promise` which will be
+     * resolved with either the doc(s) or rejected with the error.
+     * Like `.then()`, but only takes a rejection handler.
+     */
+    catch: Promise<ResultType>["catch"];
+
+    /** Specifies a `$center` or `$centerSphere` condition. */
+    circle(area: any): this;
+    circle(path: string, area: any): this;
+
     /** Adds a collation to this op (MongoDB 3.4 and up) */
     collation(value: mongodb.CollationDocument): this;
 
@@ -951,6 +969,12 @@ declare module "mongoose" {
     countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType>;
     countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
 
+    /**
+     * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
+     * A QueryCursor exposes a Streams3 interface, as well as a `.next()` function.
+     */
+    cursor(options?: any): QueryCursor<DocType>;
+
     /**
      * Declare and/or execute this query as a `deleteMany()` operation. Works like
      * remove, except it deletes _every_ document that matches `filter` in the
@@ -985,6 +1009,9 @@ declare module "mongoose" {
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
     estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType>;
 
+    /** Executes the query */
+    exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
+
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
     exists(path: string, val: boolean): this;
@@ -1020,6 +1047,9 @@ declare module "mongoose" {
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
+    /** Specifies a `$geometry` condition */
+    geometry(object: { type: string, coordinates: any[] }): this;
+
     /**
      * For update operations, returns the value of a path in the update's `$set`.
      * Useful for writing getters/setters that can work with both update operations
@@ -1033,6 +1063,9 @@ declare module "mongoose" {
     /** Gets query options. */
     getOptions(): QueryOptions;
 
+    /** Gets a list of paths to be populated by this query */
+    getPopulatedPaths(): Array<string>;
+
     /** Returns the current query filter. Equivalent to `getFilter()`. */
     getQuery(): FilterQuery<DocType>;
 
@@ -1054,6 +1087,9 @@ declare module "mongoose" {
     in(val: Array<any>): this;
     in(path: string, val: Array<any>): this;
 
+    /** Declares an intersects query for `geometry()`. */
+    intersects(arg?: any): this;
+
     /** Requests acknowledgement that this operation has been persisted to MongoDB's on-disk journal. */
     j(val: boolean | null): this;
 
@@ -1071,6 +1107,12 @@ declare module "mongoose" {
     lte(val: number): this;
     lte(path: string, val: number): this;
 
+    /**
+     * Runs a function `fn` and treats the return value of `fn` as the new value
+     * for the query to resolve to.
+     */
+    map<MappedType>(fn: (doc: DocType) => MappedType): Query<MappedType, DocType>;
+
     /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     maxDistance(val: number): this;
     maxDistance(path: string, val: number): this;
@@ -1102,6 +1144,10 @@ declare module "mongoose" {
     ne(val: any): this;
     ne(path: string, val: any);
 
+    /** Specifies a `$near` or `$nearSphere` condition */
+    near(val: any): this;
+    near(path: string, val: any): this;
+
     /** Specifies an `$nin` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     nin(val: Array<any>): this;
     nin(path: string, val: Array<any>): this;
@@ -1112,6 +1158,21 @@ declare module "mongoose" {
     /** Specifies arguments for an `$or` condition. */
     or(array: Array<FilterQuery<DocType>>): this;
 
+    /**
+     * Make this query throw an error if no documents match the given `filter`.
+     * This is handy for integrating with async/await, because `orFail()` saves you
+     * an extra `if` statement to check if no document was found.
+     */
+    orFail(err?: Error | (() => Error)): this;
+
+    /** Specifies a `$polygon` condition */
+    polygon(...coordinatePairs: number[][]): this;
+    polygon(path: string, ...coordinatePairs: number[][]): this;
+
+    /** Specifies paths which should be populated with other documents. */
+    populate(path: string | any, select?: string | any, model?: string | Model<any>, match?: any): this;
+    populate(options: PopulateOptions | Array<PopulateOptions>): this;
+
     /** Get/set the current projection (AKA fields). Pass `null` to remove the current projection. */
     projection(fields?: any | null): any;
 
@@ -1132,9 +1193,25 @@ declare module "mongoose" {
      */
     remove(filter?: FilterQuery<DocType>, callback?: (err: Error | null, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType>;
 
+    /**
+     * Declare and/or execute this query as a replaceOne() operation. Same as
+     * `update()`, except MongoDB will replace the existing document and will
+     * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
+     */
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, DocType>;
+
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;
 
+    /** Determines if field selection has been made. */
+    selected(): boolean;
+
+    /** Determines if exclusive field selection has been made. */
+    selectedExclusively(): boolean;
+
+    /** Determines if inclusive field selection has been made. */
+    selectedInclusively(): boolean;
+
     /**
      * Sets the [MongoDB session](https://docs.mongodb.com/manual/reference/server-sessions/)
      * associated with this query. Sessions are how you mark a query as part of a
@@ -1174,9 +1251,38 @@ declare module "mongoose" {
     /** Sets the sort order. If an object is passed, values allowed are `asc`, `desc`, `ascending`, `descending`, `1`, and `-1`. */
     sort(arg: string | any): this;
 
+    /** Sets the tailable option (for use with capped collections). */
+    tailable(bool?: boolean, opts?: {
+      numberOfRetries?: number;
+      tailableRetryInterval?: number;
+    }): this;
+
+    /**
+     * Executes the query returning a `Promise` which will be
+     * resolved with either the doc(s) or rejected with the error.
+     */
+    then: Promise<ResultType>["then"];
+
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
     toConstructor(): new (filter?: FilterQuery<DocType>, options?: QueryOptions) => Query<ResultType, DocType>;
 
+    /** Declare and/or execute this query as an update() operation. */
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+
+    /**
+     * Declare and/or execute this query as an updateMany() operation. Same as
+     * `update()`, except MongoDB will update _all_ documents that match
+     * `filter` (as opposed to just the first one) regardless of the value of
+     * the `multi` option.
+     */
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+
+    /**
+     * Declare and/or execute this query as an updateOne() operation. Same as
+     * `update()`, except it does not support the `multi` or `overwrite` options.
+     */
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
      * that must acknowledge this write before this write is considered successful.
@@ -1212,6 +1318,44 @@ declare module "mongoose" {
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>
 
+  class QueryCursor<DocType extends Document> extends stream.Readable {
+    /**
+     * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
+     * Useful for setting the `noCursorTimeout` and `tailable` flags.
+     */
+    addCursorFlag(flag: string, value: boolean);
+
+    /**
+     * Marks this cursor as closed. Will stop streaming and subsequent calls to
+     * `next()` will error.
+     */
+    close(): Promise<void>;
+    close(callback: (err: Error | null) => void): void;
+
+    /**
+     * Execute `fn` for every document in the cursor. If `fn` returns a promise,
+     * will wait for the promise to resolve before iterating on to the next one.
+     * Returns a promise that resolves when done.
+     */
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }): Promise<void>;
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }, cb?: (err: Error | null) => void): void;
+
+    /**
+     * Registers a transform function which subsequently maps documents retrieved
+     * via the streams interface or `.next()`
+     */
+    map<ResultType extends Document>(fn: (res: DocType) => ResultType): QueryCursor<ResultType>;
+
+    /**
+     * Get the next document from this cursor. Will return `null` when there are
+     * no documents left.
+     */
+    next(): Promise<DocType>;
+    next(callback: (err: Error | null, doc: DocType | null) => void): void;
+
+    options: any;
+  }
+
   class Aggregate<R> {
     /**
      * Sets an option on this aggregation. This function will be deprecated in a
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index f82b2fdb571..39ca42a474f 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -94,6 +94,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('query cursors', function() {
+    const errors = runTest('querycursor.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index f18bf1014f8..d07e24e379c 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -19,5 +19,6 @@ Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).
 Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
 
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).then((res: ITest | null) => console.log(res));
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
\ No newline at end of file
diff --git a/test/typescript/querycursor.ts b/test/typescript/querycursor.ts
new file mode 100644
index 00000000000..ff80c6f14a7
--- /dev/null
+++ b/test/typescript/querycursor.ts
@@ -0,0 +1,13 @@
+import { Schema, model, Document, Types } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Document {
+  _id?: Types.ObjectId,
+  name?: string;
+}
+
+const Test = model<ITest>('Test', schema);
+
+Test.find().cursor().eachAsync(async (doc: ITest) => console.log(doc.name)).
+  then(() => console.log('Done!'));
\ No newline at end of file

From 0f75ec5dfd1b6845e4336cc5a6950de0c1506e19 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 12:16:17 -0400
Subject: [PATCH 1287/2348] test(map): repro #9493

---
 test/types.map.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index a446e72c8b5..a62004f7401 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -934,4 +934,26 @@ describe('Map', function() {
     });
     return doc.validate();
   });
+
+  it('persists `.clear()` (gh-9493)', function() {
+    const BoardSchema = new Schema({
+      _id: { type: String },
+      elements: { type: Map, default: new Map() }
+    });
+
+    const BoardModel = db.model('Test', BoardSchema);
+
+    return co(function*() {
+      let board = new BoardModel({ _id: 'test' });
+      board.elements.set('a', 1);
+      yield board.save();
+
+      board = yield BoardModel.findById('test').exec();
+      board.elements.clear();
+      yield board.save();
+
+      board = yield BoardModel.findById('test').exec();
+      assert.equal(board.elements.size, 0);
+    });
+  });
 });

From 62abe7a2cf5ca0f8a71b146951ecdeadb3744bca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 12:25:57 -0400
Subject: [PATCH 1288/2348] fix(map): make `save()` persist `Map#clear()`

Fix #9493
---
 lib/types/map.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/types/map.js b/lib/types/map.js
index 73c926930fc..f50402e1341 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -99,6 +99,14 @@ class MongooseMap extends Map {
     }
   }
 
+  clear() {
+    super.clear();
+    const parent = this.$__parent;
+    if (parent != null) {
+      parent.markModified(this.$__path);
+    }
+  }
+
   delete(key) {
     this.set(key, undefined);
     super.delete(key);

From eacb26c84b3c6b99c899a8fbe215c4d0d4adf0f3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 12:56:46 -0400
Subject: [PATCH 1289/2348] fix(connection): don't throw Atlas error if server
 discovery doesn't find any servers

Fix #9470
---
 lib/helpers/topology/allServersUnknown.js | 4 ++--
 lib/helpers/topology/isAtlas.js           | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/topology/allServersUnknown.js b/lib/helpers/topology/allServersUnknown.js
index f85b7279184..d3c7b4b07b4 100644
--- a/lib/helpers/topology/allServersUnknown.js
+++ b/lib/helpers/topology/allServersUnknown.js
@@ -6,6 +6,6 @@ module.exports = function allServersUnknown(topologyDescription) {
     return false;
   }
 
-  return Array.from(topologyDescription.servers.values()).
-    every(server => server.type === 'Unknown');
+  const servers = Array.from(topologyDescription.servers.values());
+  return servers.length > 0 && servers.every(server => server.type === 'Unknown');
 };
\ No newline at end of file
diff --git a/lib/helpers/topology/isAtlas.js b/lib/helpers/topology/isAtlas.js
index b7647fd5abb..3bb8129e3b7 100644
--- a/lib/helpers/topology/isAtlas.js
+++ b/lib/helpers/topology/isAtlas.js
@@ -6,6 +6,7 @@ module.exports = function isAtlas(topologyDescription) {
     return false;
   }
 
-  return Array.from(topologyDescription.servers.keys()).
-    every(host => host.endsWith('.mongodb.net:27017'));
+  const hostnames = Array.from(topologyDescription.servers.keys());
+  return hostnames.length > 0 &&
+    hostnames.every(host => host.endsWith('.mongodb.net:27017'));
 };
\ No newline at end of file

From 07ae7f02a0a00dbd4a135e68d30dc8be9aa591be Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 14:25:21 -0400
Subject: [PATCH 1290/2348] chore: add post hooks to TypeScript definitions re:
 #8108

---
 index.d.ts                    | 12 ++++++++++++
 lib/schema.js                 |  2 +-
 test/typescript/main.test.js  |  9 +++++++++
 test/typescript/middleware.ts | 34 ++++++++++++++++++++++++++++++++++
 4 files changed, 56 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/middleware.ts

diff --git a/index.d.ts b/index.d.ts
index 36c30999d70..720d15f26eb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -777,6 +777,18 @@ declare module "mongoose" {
     /** Returns the pathType of `path` for this schema. */
     pathType(path: string): string;
 
+    /** Defines a post hook for the model. */
+    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: Error | null) => void) => void): this;
+    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
+
+    /** Defines a pre hook for the model. */
+    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
+    pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
+
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
 
diff --git a/lib/schema.js b/lib/schema.js
index 2abd0a01a28..ac53fa829cf 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1277,7 +1277,7 @@ Schema.prototype.queue = function(name, args) {
 };
 
 /**
- * Defines a pre hook for the document.
+ * Defines a pre hook for the model.
  *
  * ####Example
  *
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 39ca42a474f..40ad544384b 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -102,6 +102,15 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('middleware', function() {
+    const errors = runTest('middleware.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.includes("Property 'notAFunction' does not exist"), errors[0].messageText);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
new file mode 100644
index 00000000000..1a131422af0
--- /dev/null
+++ b/test/typescript/middleware.ts
@@ -0,0 +1,34 @@
+import { Schema, model, Model, Document, Types, Query, Aggregate } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+schema.pre<Query<any, any>>('find', async function() {
+  console.log('Find', this.getFilter());
+});
+
+schema.pre<Query<any, any>>('find', async function() {
+  console.log('Find', this.notAFunction());
+});
+
+schema.pre<Aggregate<any>>('aggregate', async function() {
+  console.log('Pipeline', this.pipeline());
+});
+
+schema.post<Aggregate<any>>('aggregate', async function(res: Array<any>) {
+  console.log('Pipeline', this.pipeline(), res[0]);
+});
+
+interface ITest extends Document {
+  _id?: Types.ObjectId,
+  name?: string;
+}
+
+schema.pre<ITest>('save', function(next) {
+  console.log(this.name);
+});
+
+schema.post<ITest>('save', function() {
+  console.log(this.name);
+});
+
+const Test = model<ITest>('Test', schema);
\ No newline at end of file

From a715d02941d975d6f7c737afdab9be832d118b25 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 14:30:47 -0400
Subject: [PATCH 1291/2348] chore: add error handling middleware to TypeScript
 definitions re: #8108

---
 index.d.ts                    | 5 +++++
 test/typescript/middleware.ts | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 720d15f26eb..d138bbcd339 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -783,6 +783,11 @@ declare module "mongoose" {
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: Error | null) => void) => void): this;
     post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
 
+    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: Error, res: any, next: (err: Error | null) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: Error, res: any, next: (err: Error | null) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: Error, res: Array<any>, next: (err: Error | null) => void) => void): this;
+    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: Error, res: any, next: (err: Error | null) => void) => void): this;
+
     /** Defines a pre hook for the model. */
     pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index 1a131422af0..00d29460c71 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -31,4 +31,8 @@ schema.post<ITest>('save', function() {
   console.log(this.name);
 });
 
+schema.post<ITest>('save', function(err: Error, res: ITest, next: Function) {
+  console.log(this.name, err.stack);
+});
+
 const Test = model<ITest>('Test', schema);
\ No newline at end of file

From 9c899f540ededcc9dddbf07767ac36f879592f61 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 14:51:31 -0400
Subject: [PATCH 1292/2348] chore: add remaining schema methods to TypeScript
 definitions re: #8108

---
 index.d.ts    | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/schema.js |  2 +-
 2 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index d138bbcd339..32152996f10 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -770,6 +770,31 @@ declare module "mongoose" {
     /** Iterates the schemas paths similar to Array#forEach. */
     eachPath(fn: (path: string, type: SchemaType) => void): this;
 
+    /** Defines an index (most likely compound) for this schema. */
+    index(fields: any, options?: any): this;
+
+    /**
+     * Returns a list of indexes that this schema declares, via `schema.index()`
+     * or by `index: true` in a path's options.
+     */
+    indexes(): Array<any>;
+
+    /** Gets a schema option. */
+    get(path: string): any;
+
+    /**
+     * Loads an ES6 class into a schema. Maps [setters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set) + [getters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get), [static methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static),
+     * and [instance methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Class_body_and_method_definitions)
+     * to schema [virtuals](http://mongoosejs.com/docs/guide.html#virtuals),
+     * [statics](http://mongoosejs.com/docs/guide.html#statics), and
+     * [methods](http://mongoosejs.com/docs/guide.html#methods).
+     */
+    loadClass(model: Function): this;
+
+    /** Adds an instance method to documents constructed from Models compiled from this schema. */
+    method(name: string, fn: Function, opts?: any): this;
+    method(methods: any): this;
+
     /** Gets/sets schema paths. */
     path(path: string): SchemaType;
     path(path: string, constructor: any): this;
@@ -777,6 +802,9 @@ declare module "mongoose" {
     /** Returns the pathType of `path` for this schema. */
     pathType(path: string): string;
 
+    /** Registers a plugin for this schema. */
+    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
+
     /** Defines a post hook for the model. */
     post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
@@ -797,8 +825,23 @@ declare module "mongoose" {
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
 
+    /** Removes the given `path` (or [`paths`]). */
+    remove(paths: string | Array<string>): this;
+
     /** Returns an Array of path strings that are required by this schema. */
     requiredPaths(invalidate?: boolean): string[];
+
+    /** Sets a schema option. */
+    set(path: string, value: any, _tags?: any): this;
+
+    /** Adds static "class" methods to Models compiled from this schema. */
+    static(name: string, fn: Function): this;
+
+    /** Creates a virtual type with the given name. */
+    virtual(name: string, options?: any): VirtualType;
+
+    /** Returns the virtual type with the given `name`. */
+    virtualpath(name: string): VirtualType | null;
   }
 
   interface SchemaDefinition {
@@ -939,6 +982,13 @@ declare module "mongoose" {
     unique?: boolean
   }
 
+  class VirtualType {
+    /** Adds a custom getter to this virtual. */
+    get(fn: Function): this;
+    /** Adds a custom setter to this virtual. */
+    set(fn: Function): this;
+  }
+
   interface Query<ResultType, DocType extends Document> {
     exec(): Promise<ResultType>;
     exec(callback?: (err: Error | null, res: ResultType) => void): void;
diff --git a/lib/schema.js b/lib/schema.js
index ac53fa829cf..d3481c7502f 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1538,7 +1538,7 @@ Schema.prototype.index = function(fields, options) {
 };
 
 /**
- * Sets/gets a schema option.
+ * Sets a schema option.
  *
  * ####Example
  *

From 5a4a37787e281f6dcf58a00b7a44eba159f9a91f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 17:58:28 -0400
Subject: [PATCH 1293/2348] chore: add aggregation cursor support and error
 namespace re: #8108

---
 index.d.ts                   | 227 +++++++++++++++++++++--------------
 test/typescript/aggregate.ts |   4 +
 test/typescript/queries.ts   |   2 +
 3 files changed, 144 insertions(+), 89 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 32152996f10..99abd6b5a62 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -5,14 +5,14 @@ declare module "mongoose" {
   import stream = require('stream');
 
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
-  export function connect(uri: string, options: ConnectOptions, callback: (err: Error) => void): void;
-  export function connect(uri: string, callback: (err: Error) => void): void;
+  export function connect(uri: string, options: ConnectOptions, callback: (err: CallbackError) => void): void;
+  export function connect(uri: string, callback: (err: CallbackError) => void): void;
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
 
   /** Creates a Connection instance. */
   export function createConnection(uri: string, options?: ConnectOptions): Promise<Connection>;
   export function createConnection(): Connection;
-  export function createConnection(uri: string, options: ConnectOptions, callback: (err: Error | null, conn: Connection) => void): void;
+  export function createConnection(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn: Connection) => void): void;
 
   export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
 
@@ -37,8 +37,8 @@ declare module "mongoose" {
 
   class Connection extends events.EventEmitter {
     /** Closes the connection */
-    close(callback: (err: Error | null) => void): void;
-    close(force: boolean, callback: (err: Error | null) => void): void;
+    close(callback: (err: CallbackError) => void): void;
+    close(force: boolean, callback: (err: CallbackError) => void): void;
     close(force?: boolean): Promise<void>;
 
     /** Retrieves a collection, creating it if not cached. */
@@ -56,8 +56,8 @@ declare module "mongoose" {
      * and [views](https://docs.mongodb.com/manual/core/views/) from mongoose.
      */
     createCollection<T = any>(name: string, options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
-    createCollection<T = any>(name: string, cb: (err: Error | null, collection: mongodb.Collection<T>) => void): void;
-    createCollection<T = any>(name: string, options: mongodb.CollectionCreateOptions, cb?: (err: Error | null, collection: mongodb.Collection) => void): Promise<mongodb.Collection<T>>;
+    createCollection<T = any>(name: string, cb: (err: CallbackError, collection: mongodb.Collection<T>) => void): void;
+    createCollection<T = any>(name: string, options: mongodb.CollectionCreateOptions, cb?: (err: CallbackError, collection: mongodb.Collection) => void): Promise<mongodb.Collection<T>>;
 
     /**
      * Removes the model named `name` from this connection, if it exists. You can
@@ -71,14 +71,14 @@ declare module "mongoose" {
      * all documents and indexes.
      */
     dropCollection(collection: string): Promise<void>;
-    dropCollection(collection: string, cb: (err: Error | null) => void): void;
+    dropCollection(collection: string, cb: (err: CallbackError) => void): void;
 
     /**
      * Helper for `dropDatabase()`. Deletes the given database, including all
      * collections, documents, and indexes.
      */
     dropDatabase(): Promise<void>;
-    dropDatabase(cb: (err: Error | null) => void): void;
+    dropDatabase(cb: (err: CallbackError) => void): void;
 
     /** Gets the value of the option `key`. Equivalent to `conn.options[key]` */
     get(key: string): any;
@@ -119,8 +119,8 @@ declare module "mongoose" {
 
     /** Opens the connection with a URI using `MongoClient.connect()`. */
     openUri(uri: string, options?: ConnectOptions): Promise<Connection>;
-    openUri(uri: string, callback: (err: Error | null, conn?: Connection) => void): Connection;
-    openUri(uri: string, options: ConnectOptions, callback: (err: Error | null, conn?: Connection) => void): Connection;
+    openUri(uri: string, callback: (err: CallbackError, conn?: Connection) => void): Connection;
+    openUri(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn?: Connection) => void): Connection;
 
     /** The password specified in the URI */
     pass: string;
@@ -252,11 +252,11 @@ declare module "mongoose" {
     db: Connection;
 
     /** Removes this document from the db. */
-    delete(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
+    delete(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
     delete(options?: QueryOptions): Query<any, this>;
 
     /** Removes this document from the db. */
-    deleteOne(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
+    deleteOne(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
     deleteOne(options?: QueryOptions): Query<any, this>;
 
     /** Takes a populated field and returns it to its unpopulated state. */
@@ -283,7 +283,7 @@ declare module "mongoose" {
 
     /** Explicitly executes population and returns a promise. Useful for promises integration. */
     execPopulate(): Promise<this>;
-    execPopulate(callback: (err: Error | null, res: this) => void): void;
+    execPopulate(callback: (err: CallbackError, res: this) => void): void;
 
     /** Returns the value of a path. */
     get(path: string, type?: any, options?: any);
@@ -305,10 +305,10 @@ declare module "mongoose" {
      * Called internally after a document is returned from mongodb. Normally,
      * you do **not** need to call this function on your own.
      */
-    init(obj: any, opts?: any, cb?: (err: Error | null, doc: this) => void): this;
+    init(obj: any, opts?: any, cb?: (err: CallbackError, doc: this) => void): this;
 
     /** Marks a path as invalid, causing validation to fail. */
-    invalidate(path: string, errorMsg: string | Error, value?: any, kind?: string): Error | null;
+    invalidate(path: string, errorMsg: string | NativeError, value?: any, kind?: string): NativeError | null;
 
     /** Returns true if `path` was directly set and modified, else false. */
     isDirectModified(path: string): boolean;
@@ -358,14 +358,14 @@ declare module "mongoose" {
      * If you want to use promises instead, use this function with
      * [`execPopulate()`](#document_Document-execPopulate).
      */
-    populate(path: string, callback?: (err: Error | null, res: this) => void): this;
-    populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: (err: Error | null, res: this) => void): this;
+    populate(path: string, callback?: (err: CallbackError, res: this) => void): this;
+    populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: (err: CallbackError, res: this) => void): this;
 
     /** Gets _id(s) used during population of the given `path`. If the path was not populated, returns `undefined`. */
     populated(path: string): any;
 
     /** Removes this document from the db. */
-    remove(options?: QueryOptions, cb?: (err: Error | null, res: any) => void): void;
+    remove(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
     remove(options?: QueryOptions): Query<any, this>;
 
     /** Sends a replaceOne command with this document `_id` as the query selector. */
@@ -373,8 +373,8 @@ declare module "mongoose" {
 
     /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
     save(options?: SaveOptions): Promise<this>;
-    save(options?: SaveOptions, fn?: (err: Error | null, doc: this) => void): void;
-    save(fn?: (err: Error | null, doc: this) => void): void;
+    save(options?: SaveOptions, fn?: (err: CallbackError, doc: this) => void): void;
+    save(fn?: (err: CallbackError, doc: this) => void): void;
 
     /** Sets the value of a path, or many paths. */
     set(path: string, val: any, options?: any): this;
@@ -391,19 +391,19 @@ declare module "mongoose" {
     unmarkModified(path: string);
 
     /** Sends an update command with this document `_id` as the query selector. */
-    update(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: Error, res: any) => void): Query<any, this>;
+    update(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
 
     /** Sends an updateOne command with this document `_id` as the query selector. */
-    updateOne(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: Error, res: any) => void): Query<any, this>;
+    updateOne(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
 
     /** Executes registered validation rules for this document. */
     validate(pathsToValidate?: Array<string>, options?: any): Promise<void>;
-    validate(callback: (err: Error | null) => void): void;
-    validate(pathsToValidate: Array<string>, callback: (err: Error | null) => void): void;
-    validate(pathsToValidate: Array<string>, options: any, callback: (err: Error | null) => void): void;
+    validate(callback: (err: CallbackError) => void): void;
+    validate(pathsToValidate: Array<string>, callback: (err: CallbackError) => void): void;
+    validate(pathsToValidate: Array<string>, options: any, callback: (err: CallbackError) => void): void;
 
     /** Executes registered validation rules (skipping asynchronous validators) for this document. */
-    validateSync(pathsToValidate?: Array<string>, options?: any): Error | null;
+    validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
 
     /** The documents schema. */
     schema: Schema;
@@ -435,15 +435,42 @@ declare module "mongoose" {
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: any, res: mongodb.BulkWriteOpResultObject) => void): void;
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions): Promise<mongodb.BulkWriteOpResultObject>;
 
+    /** Creates a `count` query: counts the number of documents that match `filter`. */
+    count(callback?: (err: any, count: number) => void): Query<number, T>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
+
+    /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
+    countDocuments(callback?: (err: any, count: number) => void): Query<number, T>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
+
     /** Creates a new document or documents */
     create(doc: T | DocumentDefinition<T>): Promise<T>;
     create(docs: Array<T | DocumentDefinition<T>>, options?: SaveOptions): Promise<Array<T>>;
     create(...docs: Array<T | DocumentDefinition<T>>): Promise<T>;
-    create(doc: T | DocumentDefinition<T>, callback: (err: Error | null, doc: T) => void): void;
-    create(docs: Array<T | DocumentDefinition<T>>, callback: (err: Error | null, docs: Array<T>) => void): void;
+    create(doc: T | DocumentDefinition<T>, callback: (err: CallbackError, doc: T) => void): void;
+    create(docs: Array<T | DocumentDefinition<T>>, callback: (err: CallbackError, docs: Array<T>) => void): void;
 
+    /**
+     * Create the collection for this model. By default, if no indexes are specified,
+     * mongoose will not create the collection for the model until any documents are
+     * created. Use this method to create the collection explicitly.
+     */
     createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
-    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: Error | null, collection: mongodb.Collection<T>) => void): void;
+    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<T>) => void): void;
+
+    /**
+     * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
+     * function.
+     */
+    createIndexes(options: any): Promise<void>;
+    createIndexes(options: any, callback?: (err: any) => void): Promise<void>;
+
+    /**
+     * Sends `createIndex` commands to mongo for each index declared in the schema.
+     * The `createIndex` commands are sent in series.
+     */
+    ensureIndexes(options: any): Promise<void>;
+    ensureIndexes(options: any, callback?: (err: any) => void): Promise<void>;
 
     /**
      * Event emitter that reports any errors that occurred. Useful for global error
@@ -451,6 +478,9 @@ declare module "mongoose" {
      */
     events: NodeJS.EventEmitter;
 
+    /** Finds one document. */
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<T | null, T>;
+
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
      * The document returned has no paths marked as modified initially.
@@ -470,8 +500,8 @@ declare module "mongoose" {
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T | InsertManyResult>;
     insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T> | InsertManyResult>;
-    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions, callback?: (err: Error | null, res: T | InsertManyResult) => void): void;
-    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions, callback?: (err: Error | null, res: Array<T> | InsertManyResult) => void): void;
+    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions, callback?: (err: CallbackError, res: T | InsertManyResult) => void): void;
+    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<T> | InsertManyResult) => void): void;
 
     /**
      * Lists the indexes currently defined in MongoDB. This may or may not be
@@ -479,7 +509,7 @@ declare module "mongoose" {
      * use the [`autoIndex` option](/docs/guide.html#autoIndex) and if you
      * build indexes manually.
      */
-    listIndexes(callback: (err: Error | null, res: Array<any>) => void): void;
+    listIndexes(callback: (err: CallbackError, res: Array<any>) => void): void;
     listIndexes(): Promise<Array<any>>;
 
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
@@ -492,7 +522,7 @@ declare module "mongoose" {
      * are in your schema but not in MongoDB.
      */
     syncIndexes(options?: object): Promise<Array<string>>;
-    syncIndexes(options: object | null, callback: (err: Error | null, dropped: Array<string>) => void): void;
+    syncIndexes(options: object | null, callback: (err: CallbackError, dropped: Array<string>) => void): void;
 
     /**
      * Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
@@ -517,34 +547,15 @@ declare module "mongoose" {
     /** Translate any aliases fields/conditions so the final query or document object is pure */
     translateAliases(raw: any): any;
 
-    /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): Query<number, T>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
-
-    /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): Query<number, T>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
-
-    /**
-     * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
-     * function.
-     */
-    createIndexes(options: any): Promise<void>;
-    createIndexes(options: any, callback?: (err: any) => void): Promise<void>;
-
     /** Adds a discriminator type. */
     discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
 
+    /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
+
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
     estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T>;
 
-    /**
-     * Sends `createIndex` commands to mongo for each index declared in the schema.
-     * The `createIndex` commands are sent in series.
-     */
-    ensureIndexes(options: any): Promise<void>;
-    ensureIndexes(options: any, callback?: (err: any) => void): Promise<void>;
-
     /**
      * Returns true if at least one document exists in the database that matches
      * the given `filter`, and false otherwise.
@@ -552,9 +563,6 @@ declare module "mongoose" {
     exists(filter: FilterQuery<T>): Promise<boolean>;
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
-    /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
-
     /** Creates a `find` query: gets a list of documents that match `filter`. */
     find(callback?: (err: any, count: number) => void): Query<Array<T>, T>;
     find(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
@@ -581,7 +589,7 @@ declare module "mongoose" {
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: Error | null, res: Array<T>) => void): Query<Array<T>, T>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
@@ -589,7 +597,7 @@ declare module "mongoose" {
       callback?: (err: any, res: any) => void
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: Error | null) => void): Query<any, T>;
+    remove(filter?: any, callback?: (err: CallbackError) => void): Query<any, T>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
     replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
@@ -806,21 +814,21 @@ declare module "mongoose" {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
 
     /** Defines a post hook for the model. */
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: Error | null) => void) => void): this;
-    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: Error | null) => void) => void): this;
+    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: Error, res: any, next: (err: Error | null) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: Error, res: any, next: (err: Error | null) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: Error, res: Array<any>, next: (err: Error | null) => void) => void): this;
-    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: Error, res: any, next: (err: Error | null) => void) => void): this;
+    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
-    pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
-    pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
-    pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: Error | null) => void) => void): this;
+    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
@@ -991,7 +999,7 @@ declare module "mongoose" {
 
   interface Query<ResultType, DocType extends Document> {
     exec(): Promise<ResultType>;
-    exec(callback?: (err: Error | null, res: ResultType) => void): void;
+    exec(callback?: (err: CallbackError, res: ResultType) => void): void;
 
     $where(argument: string | Function): Query<Array<DocType>, DocType>;
 
@@ -1047,14 +1055,14 @@ declare module "mongoose" {
      * remove, except it deletes _every_ document that matches `filter` in the
      * collection, regardless of the value of `single`.
      */
-    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
 
     /**
      * Declare and/or execute this query as a `deleteOne()` operation. Works like
      * remove, except it deletes at most one document regardless of the `single`
      * option.
      */
-    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType>;
@@ -1067,8 +1075,8 @@ declare module "mongoose" {
      * Gets/sets the error flag on this query. If this flag is not null or
      * undefined, the `exec()` promise will reject without executing.
      */
-    error(): Error | null;
-    error(val: Error | null): this;
+    error(): NativeError | null;
+    error(val: NativeError | null): this;
 
     /** Specifies the complementary comparison value for paths specified with `where()` */
     equals(val: any): this;
@@ -1094,10 +1102,10 @@ declare module "mongoose" {
     /** Creates a `find` query: gets a list of documents that match `filter`. */
     find(callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
     find(filter: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: Error | null, count: number) => void): Query<Array<DocType>, DocType>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<Array<DocType>, DocType>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
-    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: Error | null, count: number) => void): Query<DocType | null, DocType>;
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
@@ -1230,7 +1238,7 @@ declare module "mongoose" {
      * This is handy for integrating with async/await, because `orFail()` saves you
      * an extra `if` statement to check if no document was found.
      */
-    orFail(err?: Error | (() => Error)): this;
+    orFail(err?: NativeError | (() => NativeError)): this;
 
     /** Specifies a `$polygon` condition */
     polygon(...coordinatePairs: number[][]): this;
@@ -1258,7 +1266,7 @@ declare module "mongoose" {
      * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
      * or [`deleteMany()`](#query_Query-deleteMany) instead. 
      */
-    remove(filter?: FilterQuery<DocType>, callback?: (err: Error | null, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType>;
+    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType>;
 
     /**
      * Declare and/or execute this query as a replaceOne() operation. Same as
@@ -1334,7 +1342,7 @@ declare module "mongoose" {
     toConstructor(): new (filter?: FilterQuery<DocType>, options?: QueryOptions) => Query<ResultType, DocType>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -1342,13 +1350,13 @@ declare module "mongoose" {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: Error | null, res: any) => void): Query<any, DocType>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
@@ -1397,7 +1405,7 @@ declare module "mongoose" {
      * `next()` will error.
      */
     close(): Promise<void>;
-    close(callback: (err: Error | null) => void): void;
+    close(callback: (err: CallbackError) => void): void;
 
     /**
      * Execute `fn` for every document in the cursor. If `fn` returns a promise,
@@ -1405,7 +1413,7 @@ declare module "mongoose" {
      * Returns a promise that resolves when done.
      */
     eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }): Promise<void>;
-    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }, cb?: (err: Error | null) => void): void;
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }, cb?: (err: CallbackError) => void): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
@@ -1418,7 +1426,7 @@ declare module "mongoose" {
      * no documents left.
      */
     next(): Promise<DocType>;
-    next(callback: (err: Error | null, doc: DocType | null) => void): void;
+    next(callback: (err: CallbackError, doc: DocType | null) => void): void;
 
     options: any;
   }
@@ -1454,7 +1462,7 @@ declare module "mongoose" {
     exec(callback?: (err: any, result: R) => void): Promise<R> | any;
 
     /** Execute the aggregation with explain */
-    explain(callback?: (err: Error, result: any) => void): Promise<any>;
+    explain(callback?: (err: CallbackError, result: any) => void): Promise<any>;
 
     /** Combines multiple aggregation pipelines. */
     facet(options: any): this;
@@ -1508,6 +1516,42 @@ declare module "mongoose" {
     sortByCount(arg: string | any): this;
   }
 
+  class AggregationCursor extends stream.Readable {
+    /**
+     * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
+     * Useful for setting the `noCursorTimeout` and `tailable` flags.
+     */
+    addCursorFlag(flag: string, value: boolean);
+
+    /**
+     * Marks this cursor as closed. Will stop streaming and subsequent calls to
+     * `next()` will error.
+     */
+    close(): Promise<void>;
+    close(callback: (err: CallbackError) => void): void;
+
+    /**
+     * Execute `fn` for every document in the cursor. If `fn` returns a promise,
+     * will wait for the promise to resolve before iterating on to the next one.
+     * Returns a promise that resolves when done.
+     */
+    eachAsync(fn: (doc: any) => any, options?: { parallel?: number }): Promise<void>;
+    eachAsync(fn: (doc: any) => any, options?: { parallel?: number }, cb?: (err: CallbackError) => void): void;
+
+    /**
+     * Registers a transform function which subsequently maps documents retrieved
+     * via the streams interface or `.next()`
+     */
+    map(fn: (res: any) => any): this;
+
+    /**
+     * Get the next document from this cursor. Will return `null` when there are
+     * no documents left.
+     */
+    next(): Promise<any>;
+    next(callback: (err: CallbackError, doc: any) => void): void;
+  }
+
   class SchemaType {
     /** SchemaType constructor */
     constructor(path: string, options?: any, instance?: string);
@@ -1595,4 +1639,9 @@ declare module "mongoose" {
     value: any;
     reason?: Error | null;
   }
+
+  class NativeError extends global.Error {}
+  type CallbackError = NativeError | null;
+
+  class Error extends global.Error {}
 }
\ No newline at end of file
diff --git a/test/typescript/aggregate.ts b/test/typescript/aggregate.ts
index fa2034c5e89..b0d6da9eca0 100644
--- a/test/typescript/aggregate.ts
+++ b/test/typescript/aggregate.ts
@@ -23,4 +23,8 @@ async function run() {
 
   let res2: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]);
   console.log(res2[0].name);
+
+  await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).cursor().exec().eachAsync(async (res) => {
+    console.log(res);
+  });
 }
\ No newline at end of file
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index d07e24e379c..b39561b04e6 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -16,6 +16,8 @@ Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => consol
 Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().
   then((res: Array<ITest>) => console.log(res[0].name));
 
+Test.findOne().orFail(new Error('bar')).then((doc: ITest) => console.log('Found! ' + doc.name));
+
 Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
 
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITest | null) => console.log(res));

From 738b7e5f979a182885a4f36cfed311f44f1465a7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 18:00:26 -0400
Subject: [PATCH 1294/2348] style: fix lint

---
 test/typescript/main.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 40ad544384b..870ea9c9c89 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -109,14 +109,14 @@ describe('typescript syntax', function() {
       console.log(errors);
     }
     assert.equal(errors.length, 1);
-    assert.ok(errors[0].messageText.includes("Property 'notAFunction' does not exist"), errors[0].messageText);
+    assert.ok(errors[0].messageText.includes('Property \'notAFunction\' does not exist'), errors[0].messageText);
   });
 });
 
 function runTest(file) {
   const program = typescript.createProgram([`${__dirname}/${file}`], tsconfig);
 
-  let emitResult = program.emit();
+  const emitResult = program.emit();
 
   return typescript.getPreEmitDiagnostics(program).concat(emitResult.diagnostics);
 }
\ No newline at end of file

From 370eadf3f93746145059564330fa76d53a67ad37 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 19:53:37 -0400
Subject: [PATCH 1295/2348] chore: add Error namespace, several more global
 exports re: #8108

---
 index.d.ts | 186 +++++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 160 insertions(+), 26 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 99abd6b5a62..65d224352a8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -4,18 +4,69 @@ declare module "mongoose" {
   import mongoose = require('mongoose');
   import stream = require('stream');
 
+  /** The various Mongoose SchemaTypes. */
+  export var SchemaTypes: typeof Schema.Types;
+
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
   export function connect(uri: string, options: ConnectOptions, callback: (err: CallbackError) => void): void;
   export function connect(uri: string, callback: (err: CallbackError) => void): void;
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
 
+  /** The Mongoose module's default connection. Equivalent to `mongoose.connections[0]`, see [`connections`](#mongoose_Mongoose-connections). */
+  export var connection: Connection;
+
+  /** An array containing all connections associated with this Mongoose instance. */
+  export var connections: Connection[];
+
   /** Creates a Connection instance. */
   export function createConnection(uri: string, options?: ConnectOptions): Promise<Connection>;
   export function createConnection(): Connection;
   export function createConnection(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn: Connection) => void): void;
 
+  /**
+   * Removes the model named `name` from the default connection, if it exists.
+   * You can use this function to clean up any models you created in your tests to
+   * prevent OverwriteModelErrors.
+   */
+  export function deleteModel(name: string | RegExp): typeof mongoose;
+
+  export function disconnect(): Promise<void>;
+  export function disconnect(cb: (err: CallbackError) => void): void;
+
   export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
 
+  /** Returns an array of model names created on this instance of Mongoose. */
+  export function modelNames(): Array<string>;
+
+  /** The node-mongodb-native driver Mongoose uses. */
+  export var mongo: typeof mongodb;
+
+  /**
+   * Mongoose uses this function to get the current time when setting
+   * [timestamps](/docs/guide.html#timestamps). You may stub out this function
+   * using a tool like [Sinon](https://www.npmjs.com/package/sinon) for testing.
+   */
+  export function now(): Date;
+
+  /** Declares a global plugin executed on all Schemas. */
+  export function plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
+
+  /** Getter/setter around function for pluralizing collection names. */
+  export function pluralize(fn?: (str: string) => string): (str: string) => string;
+
+  /**
+   * _Requires MongoDB >= 3.6.0._ Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
+   * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
+   * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
+   */
+  export function startSession(options?: mongodb.SessionOptions): Promise<mongodb.ClientSession>;
+  export function startSession(options: mongodb.SessionOptions, cb: (err: any, session: mongodb.ClientSession) => void): void;
+
+  /** The Mongoose version */
+  export var version: string;
+
+  export type CastError = Error.CastError;
+
   type Mongoose = typeof mongoose;
 
   interface ConnectOptions extends mongodb.MongoClientOptions {
@@ -279,7 +330,7 @@ declare module "mongoose" {
     equals(doc: Document): boolean;
 
     /** Hash containing current validation errors. */
-    errors?: ValidationError;
+    errors?: Error.ValidationError;
 
     /** Explicitly executes population and returns a promise. Useful for promises integration. */
     execPopulate(): Promise<this>;
@@ -666,7 +717,7 @@ declare module "mongoose" {
   }
 
   interface InsertManyResult extends mongodb.InsertWriteOpResult<any> {
-    mongoose?: { validationErrors?: Array<Error> }
+    mongoose?: { validationErrors?: Array<Error.CastError | Error.ValidatorError> }
   }
 
   interface MapReduceOptions<T, Key, Val> {
@@ -997,6 +1048,15 @@ declare module "mongoose" {
     set(fn: Function): this;
   }
 
+  namespace Schema {
+    namespace Types {
+      class Array extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+      }
+    }
+  }
+
   interface Query<ResultType, DocType extends Document> {
     exec(): Promise<ResultType>;
     exec(callback?: (err: CallbackError, res: ResultType) => void): void;
@@ -1615,33 +1675,107 @@ declare module "mongoose" {
       type?: string): this;
   }
 
-  class ValidationError extends Error {
-    name: 'ValidationError';
+  class NativeError extends global.Error {}
+  type CallbackError = NativeError | null;
 
-    errors: {[path: string]: ValidatorError | CastError};
-  }
+  class Error extends global.Error {
+    constructor(msg: string);
 
-  class CastError extends Error {
-    name: 'CastError';
-    stringValue: string;
-    kind: string;
-    value: any;
-    path: string;
-    reason?: any;
-    model?: any;
-  }
+    /** The type of error. "MongooseError" for generic errors. */
+    name: string;
 
-  class ValidatorError extends Error {
-    name: 'ValidatorError';
-    properties: {message: string, type?: string, path?: string, value?: any, reason?: any};
-    kind: string;
-    path: string;
-    value: any;
-    reason?: Error | null;
-  }
+    static messages: any;
 
-  class NativeError extends global.Error {}
-  type CallbackError = NativeError | null;
+    static Messages: any;
+  }
 
-  class Error extends global.Error {}
+  module Error {
+    export class CastError extends Error {
+      name: 'CastError';
+      stringValue: string;
+      kind: string;
+      value: any;
+      path: string;
+      reason?: NativeError | null;
+      model?: any;
+    }
+
+    export class DisconnectedError extends Error {
+      name: 'DisconnectedError';
+    }
+
+    export class DivergentArrayError extends Error {
+      name: 'DivergentArrayError';
+    }
+
+    export class MissingSchemaError extends Error {
+      name: 'MissingSchemaError';
+    }
+
+    export class DocumentNotFoundError extends Error {
+      name: 'DocumentNotFoundError';
+      result: any;
+      numAffected: number;
+      filter: any;
+      query: any;
+    }
+
+    export class ObjectExpectedError extends Error {
+      name: 'ObjectExpectedError';
+      path: string;
+    }
+
+    export class ObjectParameterError extends Error {
+      name: 'ObjectParameterError';
+    }
+
+    export class OverwriteModelError extends Error {
+      name: 'OverwriteModelError';
+    }
+
+    export class ParallelSaveError extends Error {
+      name: 'ParallelSaveError';
+    }
+
+    export class ParallelValidateError extends Error {
+      name: 'ParallelValidateError';
+    }
+
+    export class MongooseServerSelectionError extends Error {
+      name: 'MongooseServerSelectionError';
+    }
+
+    export class StrictModeError extends Error {
+      name: 'StrictModeError';
+      isImmutableError: boolean;
+      path: string;
+    }
+
+    export class ValidationError extends Error {
+      name: 'ValidationError';
+  
+      errors: {[path: string]: ValidatorError | CastError};
+    }
+  
+    export class ValidatorError extends Error {
+      name: 'ValidatorError';
+      properties: {
+        message: string,
+        type?: string,
+        path?: string,
+        value?: any,
+        reason?: any
+      };
+      kind: string;
+      path: string;
+      value: any;
+      reason?: Error | null;
+    }
+
+    export class VersionError extends Error {
+      name: 'VersionError';
+      version: number;
+      modifiedPaths: Array<string>;
+    }
+  }
 }
\ No newline at end of file

From 32e8a1d2ddfca80a651cd1a81abf3a9ba487fb8c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Oct 2020 20:57:30 -0400
Subject: [PATCH 1296/2348] chore: add Schema.Types and Types to TypeScript
 definitions re: #8108

---
 index.d.ts | 185 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 185 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 65d224352a8..f0095664223 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1053,7 +1053,187 @@ declare module "mongoose" {
       class Array extends SchemaType {
         /** This schema type's name, to defend against minifiers that mangle function names. */
         static schemaName: string;
+
+        static options: { castNonArrays: boolean; };
+
+        discriminator(name: string, schema: Schema, tag?: string);
+
+        /**
+         * Adds an enum validator if this is an array of strings or numbers. Equivalent to
+         * `SchemaString.prototype.enum()` or `SchemaNumber.prototype.enum()`
+         */
+        enum(vals: string[] | number[]);
+      }
+
+      class Boolean extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        /** Configure which values get casted to `true`. */
+        static convertToTrue: Set<any>;
+
+        /** Configure which values get casted to `false`. */
+        static convertToFalse: Set<any>;
+      }
+
+      class Buffer extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        /**
+         * Sets the default [subtype](https://studio3t.com/whats-new/best-practices-uuid-mongodb/)
+         * for this buffer. You can find a [list of allowed subtypes here](http://api.mongodb.com/python/current/api/bson/binary.html).
+         */
+        subtype(subtype: number): this;
+      }
+
+      class Date extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        /** Declares a TTL index (rounded to the nearest second) for _Date_ types only. */
+        expires(when: number | string): this;
+
+        /** Sets a maximum date validator. */
+        max(value: Date, message: string): this;
+
+        /** Sets a minimum date validator. */
+        min(value: Date, message: string): this;
       }
+
+      class Decimal128 extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+      }
+
+      class DocumentArray extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        static options: { castNonArrays: boolean; };
+
+        discriminator(name: string, schema: Schema, tag?: string);
+      }
+
+      class Map extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+      }
+
+      class Mixed extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+      }
+
+      class Number extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        /** Sets a enum validator */
+        enum(vals: number[]);
+
+        /** Sets a maximum number validator. */
+        max(value: number, message: string): this;
+
+        /** Sets a minimum number validator. */
+        min(value: number, message: string): this;
+      }
+
+      class ObjectId extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        /** Adds an auto-generated ObjectId default if turnOn is true. */
+        auto(turnOn: boolean): this;
+      }
+
+      class Embedded extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+      }
+
+      class String extends SchemaType {
+        /** This schema type's name, to defend against minifiers that mangle function names. */
+        static schemaName: string;
+
+        /** Adds an enum validator */
+        enum(vals: string[] | any): this;
+
+        /** Adds a lowercase [setter](http://mongoosejs.com/docs/api.html#schematype_SchemaType-set). */
+        lowercase(shouldApply?: boolean): this;
+
+        /** Sets a regexp validator. */
+        match(value: RegExp, message: string): this;
+
+        /** Sets a maximum length validator. */
+        maxlength(value: number, message: string): this;
+
+        /** Sets a minimum length validator. */
+        minlength(value: number, message: string): this;
+
+        /** Adds a trim [setter](http://mongoosejs.com/docs/api.html#schematype_SchemaType-set). */
+        trim(shouldTrim?: boolean): this;
+
+        /** Adds an uppercase [setter](http://mongoosejs.com/docs/api.html#schematype_SchemaType-set). */
+        uppercase(shouldApply?: boolean): this;
+      }
+    }
+  }
+
+  namespace Types {
+    class Subdocument extends Document {
+      $isSingleNested: true;
+
+      /** Returns the top level document of this sub-document. */
+      ownerDocument(): Document;
+
+      /** Returns this sub-documents parent document. */
+      parent(): Document;
+    }
+
+    class Array<T> extends global.Array<T> {
+      /** Pops the array atomically at most one time per document `save()`. */
+      $pop(): T;
+
+      /** Atomically shifts the array at most one time per document `save()`. */
+      $shift(): T;
+
+      /** Adds values to the array if not already present. */
+      addToSet(...args: any[]): any[];
+
+      isMongooseArray: true;
+
+      /** Pushes items to the array non-atomically. */
+      nonAtomicPush(...args: any[]): number;
+
+      /**
+       * Pulls items from the array atomically. Equality is determined by casting
+       * the provided value to an embedded document and comparing using
+       * [the `Document.equals()` function.](./api.html#document_Document-equals)
+       */
+      pull(...args: any[]): this;
+
+      /**
+       * Alias of [pull](#mongoosearray_MongooseArray-pull)
+       */
+      remove(...args: any[]): this;
+
+      /** Sets the casted `val` at index `i` and marks the array modified. */
+      set(i: number, val: T): this;
+
+      /** Atomically shifts the array at most one time per document `save()`. */
+      shift(): T;
+
+      /** Returns a native js Array. */
+      toObject(options: ToObjectOptions): any;
+    }
+
+    class Buffer extends global.Buffer {
+      /** Sets the subtype option and marks the buffer modified. */
+      subtype(subtype: number | ToObjectOptions): void;
+
+      /** Converts this buffer to its Binary type representation. */
+      toObject(subtype?: number): mongodb.Binary;
     }
   }
 
@@ -1619,12 +1799,17 @@ declare module "mongoose" {
     /** Get/set the function used to cast arbitrary values to this type. */
     static cast(caster?: Function | boolean): Function;
 
+    static checkRequired(checkRequired: (v: any) => boolean);
+
     /** Sets a default option for this schema type. */
     static set(option: string, value: any): void;
 
     /** Attaches a getter for all instances of this schema type. */
     static get(getter: (value: any) => any): void;
 
+    /** Get/set the function used to cast arbitrary values to this type. */
+    cast(caster: (v: any) => any): (v: any) => any;
+
     /** Sets a default value for this SchemaType. */
     default(val: any): any;
 

From 01d24b8baac5c5cc75988c77b8565982081c0adb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 25 Oct 2020 12:55:12 -0400
Subject: [PATCH 1297/2348] chore(index.d.ts): finish types and global exports
 re: #8108

---
 index.d.ts | 99 ++++++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 85 insertions(+), 14 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index f0095664223..a4a2f28a70b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -4,6 +4,43 @@ declare module "mongoose" {
   import mongoose = require('mongoose');
   import stream = require('stream');
 
+  /** The Mongoose Date [SchemaType](/docs/schematypes.html). */
+  export type Date = Schema.Types.Date;
+
+  /**
+   * The Mongoose Decimal128 [SchemaType](/docs/schematypes.html). Used for
+   * declaring paths in your schema that should be
+   * [128-bit decimal floating points](http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-decimal.html).
+   * Do not use this to create a new Decimal128 instance, use `mongoose.Types.Decimal128`
+   * instead.
+   */
+  export type Decimal128 = Schema.Types.Decimal128;
+
+  /**
+   * The Mongoose Mixed [SchemaType](/docs/schematypes.html). Used for
+   * declaring paths in your schema that Mongoose's change tracking, casting,
+   * and validation should ignore.
+   */
+  export type Mixed = Schema.Types.Mixed;
+
+  /**
+   * The Mongoose Number [SchemaType](/docs/schematypes.html). Used for
+   * declaring paths in your schema that Mongoose should cast to numbers.
+   */
+  export type Number = Schema.Types.Number;
+
+  /**
+   * The Mongoose ObjectId [SchemaType](/docs/schematypes.html). Used for
+   * declaring paths in your schema that should be
+   * [MongoDB ObjectIds](https://docs.mongodb.com/manual/reference/method/ObjectId/).
+   * Do not use this to create a new ObjectId instance, use `mongoose.Types.ObjectId`
+   * instead.
+   */
+  export type ObjectId = Schema.Types.ObjectId;
+
+  export var Promise: any;
+  export var PromiseProvider: any;
+
   /** The various Mongoose SchemaTypes. */
   export var SchemaTypes: typeof Schema.Types;
 
@@ -33,6 +70,12 @@ declare module "mongoose" {
   export function disconnect(): Promise<void>;
   export function disconnect(cb: (err: CallbackError) => void): void;
 
+  /**
+   * Returns true if Mongoose can cast the given value to an ObjectId, or
+   * false otherwise.
+   */
+  export function isValidObjectId(v: any): boolean;
+
   export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
 
   /** Returns an array of model names created on this instance of Mongoose. */
@@ -236,10 +279,6 @@ declare module "mongoose" {
 
   class Collection {}
 
-  namespace Types {
-    class ObjectId extends mongodb.ObjectID {}
-  }
-
   class Document {
     constructor(doc?: any);
 
@@ -1181,16 +1220,6 @@ declare module "mongoose" {
   }
 
   namespace Types {
-    class Subdocument extends Document {
-      $isSingleNested: true;
-
-      /** Returns the top level document of this sub-document. */
-      ownerDocument(): Document;
-
-      /** Returns this sub-documents parent document. */
-      parent(): Document;
-    }
-
     class Array<T> extends global.Array<T> {
       /** Pops the array atomically at most one time per document `save()`. */
       $pop(): T;
@@ -1235,6 +1264,48 @@ declare module "mongoose" {
       /** Converts this buffer to its Binary type representation. */
       toObject(subtype?: number): mongodb.Binary;
     }
+
+    class Decimal128 extends mongodb.Decimal128 { }
+
+    class DocumentArray<T extends Document> extends Types.Array<T> {
+      isMongooseDocumentArray: true;
+
+      /** Creates a subdocument casted to this schema. */
+      create(obj: any): T;
+
+      /** Searches array items for the first document with a matching _id. */
+      id(id: any): T | null;
+    }
+
+    class EmbeddedDocument extends Document {
+      /** Returns the top level document of this sub-document. */
+      ownerDocument(): Document;
+
+      /** Returns this sub-documents parent document. */
+      parent(): Document;
+
+      /** Returns this sub-documents parent array. */
+      parentArray(): DocumentArray<Document>;
+    }
+
+    class Map<V> extends global.Map<string, V> {
+      /** Converts a Mongoose map into a vanilla JavaScript map. */
+      toObject(options: ToObjectOptions & { flattenMaps?: boolean }): any;
+    }
+
+    class ObjectId extends mongodb.ObjectID {
+      _id?: ObjectId;
+    }
+
+    class Subdocument extends Document {
+      $isSingleNested: true;
+
+      /** Returns the top level document of this sub-document. */
+      ownerDocument(): Document;
+
+      /** Returns this sub-documents parent document. */
+      parent(): Document;
+    }
   }
 
   interface Query<ResultType, DocType extends Document> {

From 0edffb88f8610079cc44bb998e80f879a8d8b11c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 25 Oct 2020 13:27:56 -0400
Subject: [PATCH 1298/2348] fix(connection): when calling `mongoose.connect()`
 multiple times in parallel, make 2nd call wait for connection before
 resolving

Fix #9476
---
 lib/connection.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 6e70a822308..eb7d4e0baf7 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -667,7 +667,10 @@ Connection.prototype.openUri = function(uri, options, callback) {
     }
 
     if (typeof callback === 'function') {
-      callback(null, this);
+      this.$initialConnection = this.$initialConnection.then(
+        () => callback(null, this),
+        err => callback(err)
+      );
     }
     return this;
   }

From dba1dde8639c3ac44b84796e81cf4dd5bc397fe4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 26 Oct 2020 18:15:17 -0400
Subject: [PATCH 1299/2348] chore: release 5.10.11

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9086e2c746b..5bdf39eedf8 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.10.11 / 2020-10-26
+====================
+ * fix(connection): when calling `mongoose.connect()` multiple times in parallel, make 2nd call wait for connection before resolving #9476
+ * fix(map): make `save()` persist `Map#clear()` #9493
+ * fix(document): avoid overwriting array subdocument when setting dotted path that isn't selected #9427
+ * fix(connection): don't throw Atlas error if server discovery doesn't find any servers #9470
+ * docs: update options for Model.findOneAndUpdate #9499 [radamson](https://github.com/radamson)
+
 5.10.10 / 2020-10-23
 ====================
  * fix(schema): handle merging schemas from separate Mongoose module instances when schema has a virtual #9471
diff --git a/package.json b/package.json
index 763a381dfec..1b064cdcd4f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.10",
+  "version": "5.10.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 0d86d891a0b96ac72b3f3fa53b0008a226b64a7c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 28 Oct 2020 21:38:15 +0200
Subject: [PATCH 1300/2348] test(connection): repro #9505

---
 test/connection.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index 41e065b0231..15049eb0a95 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1226,4 +1226,17 @@ describe('connections:', function() {
     });
   });
 
+  it('connection.then(...) does not throw when passed undefined (gh-9505)', function() {
+    const m = new mongoose.Mongoose;
+
+    const db = m.createConnection('mongodb://localhost:27017/test_gh9505', {
+      useNewUrlParser: true,
+      useUnifiedTopology: true
+    });
+
+    assert.doesNotThrow(() => {
+      db.then(null);
+    });
+  });
+
 });

From c82d1497d364648c0a6427bedbc61c98abcbcc0b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 28 Oct 2020 21:38:59 +0200
Subject: [PATCH 1301/2348] fix(connection): avoid executing promise handler
 unless it's a function

---
 lib/connection.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index eb7d4e0baf7..9ff91531583 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -814,7 +814,11 @@ Connection.prototype.openUri = function(uri, options, callback) {
       throw err;
     });
   this.then = function(resolve, reject) {
-    return this.$initialConnection.then(() => resolve(_this), reject);
+    return this.$initialConnection.then(() => {
+      if (typeof resolve === 'function') {
+        resolve(_this);
+      }
+    }, reject);
   };
   this.catch = function(reject) {
     return this.$initialConnection.catch(reject);

From e34d0f9d8220086b9c7cb22c90c80250d38c1686 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Oct 2020 16:54:55 -0400
Subject: [PATCH 1302/2348] test(document): repro #9501

---
 test/document.test.js | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 7aebf8ce278..0335b9f8fcf 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9512,6 +9512,48 @@ describe('document', function() {
       const fromDb = yield Test.findById(doc._id);
       assert.deepEqual(fromDb.toObject().arr, [{ val: 2 }, { val: 2 }]);
     });
+  });
+
+  it('ignore getters when diffing objects for change tracking (gh-9501)', function() {
+    const schema = new Schema({
+      title: {
+        type: String,
+        required: true
+      },
+      price: {
+        type: Number,
+        min: 0
+      },
+      taxPercent: {
+        type: Number,
+        required: function() {
+          return this.price != null;
+        },
+        min: 0,
+        max: 100,
+        get: value => value || 10
+      }
+    });
 
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield Test.create({
+        title: 'original'
+      });
+
+      doc.set({
+        title: 'updated',
+        price: 10,
+        taxPercent: 10
+      });
+
+      assert.ok(doc.modifiedPaths().includes('taxPercent'));
+
+      yield doc.save();
+
+      const fromDb = yield Test.findById(doc).lean();
+      assert.equal(fromDb.taxPercent, 10);
+    });
   });
 });

From ac47d82f9ee174bbc5d5bf738279fc19ac4cc879 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Oct 2020 16:55:07 -0400
Subject: [PATCH 1303/2348] fix(document): ignore getters when diffing values
 for change tracking

Fix #9501
---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 11dece69181..9e8cb9abe67 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1416,7 +1416,7 @@ Document.prototype.$__shouldModify = function(pathToMark, path, constructing, pa
     return false;
   }
 
-  if (!deepEqual(val, priorVal || this.get(path))) {
+  if (!deepEqual(val, priorVal || utils.getValue(path, this))) {
     return true;
   }
 

From 878b6b2c1ff54cc70fa82901ed63db875652e0d9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Oct 2020 17:07:00 -0400
Subject: [PATCH 1304/2348] test: fix tests for #9501

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 0335b9f8fcf..291eb96fa0a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9548,7 +9548,7 @@ describe('document', function() {
         taxPercent: 10
       });
 
-      assert.ok(doc.modifiedPaths().includes('taxPercent'));
+      assert.ok(doc.modifiedPaths().indexOf('taxPercent') !== -1);
 
       yield doc.save();
 

From 0fffe252c00a3239ee757d8e7b52312165ed68c1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 30 Oct 2020 10:17:50 -0400
Subject: [PATCH 1305/2348] docs(model+query): clarify that `deleteOne` and
 `deleteMany` trigger middleware

Fix #9504
---
 lib/model.js | 10 ++++++----
 lib/query.js | 14 +++++++++-----
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 69979619560..de7ab0a26a4 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1909,11 +1909,12 @@ Model.remove = function remove(conditions, options, callback) {
  *
  * ####Example:
  *
- *     Character.deleteOne({ name: 'Eddard Stark' }, function (err) {});
+ *     await Character.deleteOne({ name: 'Eddard Stark' });
  *
  * ####Note:
  *
- * Like `Model.remove()`, this function does **not** trigger `pre('remove')` or `post('remove')` hooks.
+ * This function triggers `deleteOne` query hooks. Read the
+ * [middleware docs](/docs/middleware.html#naming) to learn more.
  *
  * @param {Object} conditions
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
@@ -1950,11 +1951,12 @@ Model.deleteOne = function deleteOne(conditions, options, callback) {
  *
  * ####Example:
  *
- *     Character.deleteMany({ name: /Stark/, age: { $gte: 18 } }, function (err) {});
+ *     await Character.deleteMany({ name: /Stark/, age: { $gte: 18 } });
  *
  * ####Note:
  *
- * Like `Model.remove()`, this function does **not** trigger `pre('remove')` or `post('remove')` hooks.
+ * This function triggers `deleteMany` query hooks. Read the
+ * [middleware docs](/docs/middleware.html#naming) to learn more.
  *
  * @param {Object} conditions
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
diff --git a/lib/query.js b/lib/query.js
index 2fd695a2aeb..d6ce0bf64e5 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2677,12 +2677,14 @@ Query.prototype._remove = wrapThunk(function(callback) {
  * remove, except it deletes at most one document regardless of the `single`
  * option.
  *
- * This function does not trigger any middleware.
+ * This function triggers `deleteOne` middleware.
  *
  * ####Example
  *
+ *     await Character.deleteOne({ name: 'Eddard Stark' });
+ *
+ *     // Using callbacks:
  *     Character.deleteOne({ name: 'Eddard Stark' }, callback);
- *     Character.deleteOne({ name: 'Eddard Stark' }).then(next);
  *
  * This function calls the MongoDB driver's [`Collection#deleteOne()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#deleteOne).
  * The returned [promise](https://mongoosejs.com/docs/queries.html) resolves to an
@@ -2761,12 +2763,14 @@ Query.prototype._deleteOne = wrapThunk(function(callback) {
  * remove, except it deletes _every_ document that matches `filter` in the
  * collection, regardless of the value of `single`.
  *
- * This function does not trigger any middleware
+ * This function triggers `deleteMany` middleware.
  *
  * ####Example
  *
- *     Character.deleteMany({ name: /Stark/, age: { $gte: 18 } }, callback)
- *     Character.deleteMany({ name: /Stark/, age: { $gte: 18 } }).then(next)
+ *     await Character.deleteMany({ name: /Stark/, age: { $gte: 18 } });
+ *
+ *     // Using callbacks:
+ *     Character.deleteMany({ name: /Stark/, age: { $gte: 18 } }, callback);
  *
  * This function calls the MongoDB driver's [`Collection#deleteMany()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#deleteMany).
  * The returned [promise](https://mongoosejs.com/docs/queries.html) resolves to an

From b970e92c2abdc6e9d1d92138f488344c6cb8c239 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 30 Oct 2020 12:08:35 -0400
Subject: [PATCH 1306/2348] feat(schema): support overwriting cast logic for
 individual schematype instances

Fix #8407
---
 lib/schema/boolean.js    | 30 +++++++++++++++++--------
 lib/schema/date.js       | 30 +++++++++++++++++--------
 lib/schema/decimal128.js | 30 +++++++++++++++++--------
 lib/schema/number.js     | 30 +++++++++++++++++--------
 lib/schema/objectid.js   | 30 +++++++++++++++++--------
 lib/schema/string.js     | 30 +++++++++++++++++--------
 lib/schematype.js        | 35 +++++++++++++++++++++++++++++
 test/schema.test.js      | 48 ++++++++++++++++++++++++++++++++++++++++
 8 files changed, 209 insertions(+), 54 deletions(-)

diff --git a/lib/schema/boolean.js b/lib/schema/boolean.js
index c2640841cf1..8ef7e28b9aa 100644
--- a/lib/schema/boolean.js
+++ b/lib/schema/boolean.js
@@ -94,18 +94,24 @@ SchemaBoolean.cast = function cast(caster) {
     return this._cast;
   }
   if (caster === false) {
-    caster = v => {
-      if (v != null && typeof v !== 'boolean') {
-        throw new Error();
-      }
-      return v;
-    };
+    caster = this._defaultCaster;
   }
   this._cast = caster;
 
   return this._cast;
 };
 
+/*!
+ * ignore
+ */
+
+SchemaBoolean._defaultCaster = v => {
+  if (v != null && typeof v !== 'boolean') {
+    throw new Error();
+  }
+  return v;
+};
+
 /*!
  * ignore
  */
@@ -188,9 +194,15 @@ Object.defineProperty(SchemaBoolean, 'convertToFalse', {
  */
 
 SchemaBoolean.prototype.cast = function(value) {
-  const castBoolean = typeof this.constructor.cast === 'function' ?
-    this.constructor.cast() :
-    SchemaBoolean.cast();
+  let castBoolean;
+  if (typeof this._castFunction === 'function') {
+    castBoolean = this._castFunction;
+  } else if (typeof this.constructor.cast === 'function') {
+    castBoolean = this.constructor.cast();
+  } else {
+    castBoolean = SchemaBoolean.cast();
+  }
+
   try {
     return castBoolean(value);
   } catch (error) {
diff --git a/lib/schema/date.js b/lib/schema/date.js
index 4b9ad1cde1e..fb7f061c1f6 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -97,18 +97,24 @@ SchemaDate.cast = function cast(caster) {
     return this._cast;
   }
   if (caster === false) {
-    caster = v => {
-      if (v != null && !(v instanceof Date)) {
-        throw new Error();
-      }
-      return v;
-    };
+    caster = this._defaultCaster;
   }
   this._cast = caster;
 
   return this._cast;
 };
 
+/*!
+ * ignore
+ */
+
+SchemaDate._defaultCaster = v => {
+  if (v != null && !(v instanceof Date)) {
+    throw new Error();
+  }
+  return v;
+};
+
 /**
  * Declares a TTL index (rounded to the nearest second) for _Date_ types only.
  *
@@ -332,9 +338,15 @@ SchemaDate.prototype.max = function(value, message) {
  */
 
 SchemaDate.prototype.cast = function(value) {
-  const castDate = typeof this.constructor.cast === 'function' ?
-    this.constructor.cast() :
-    SchemaDate.cast();
+  let castDate;
+  if (typeof this._castFunction === 'function') {
+    castDate = this._castFunction;
+  } else if (typeof this.constructor.cast === 'function') {
+    castDate = this.constructor.cast();
+  } else {
+    castDate = SchemaDate.cast();
+  }
+
   try {
     return castDate(value);
   } catch (error) {
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index ca9bcb4737b..0c8038f207d 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -97,18 +97,24 @@ Decimal128.cast = function cast(caster) {
     return this._cast;
   }
   if (caster === false) {
-    caster = v => {
-      if (v != null && !(v instanceof Decimal128Type)) {
-        throw new Error();
-      }
-      return v;
-    };
+    caster = this._defaultCaster;
   }
   this._cast = caster;
 
   return this._cast;
 };
 
+/*!
+ * ignore
+ */
+
+Decimal128._defaultCaster = v => {
+  if (v != null && !(v instanceof Decimal128Type)) {
+    throw new Error();
+  }
+  return v;
+};
+
 /*!
  * ignore
  */
@@ -202,9 +208,15 @@ Decimal128.prototype.cast = function(value, doc, init) {
     return ret;
   }
 
-  const castDecimal128 = typeof this.constructor.cast === 'function' ?
-    this.constructor.cast() :
-    Decimal128.cast();
+  let castDecimal128;
+  if (typeof this._castFunction === 'function') {
+    castDecimal128 = this._castFunction;
+  } else if (typeof this.constructor.cast === 'function') {
+    castDecimal128 = this.constructor.cast();
+  } else {
+    castDecimal128 = Decimal128.cast();
+  }
+
   try {
     return castDecimal128(value);
   } catch (error) {
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 719a1aa80f2..4f4f1acc9f4 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -103,18 +103,24 @@ SchemaNumber.cast = function cast(caster) {
     return this._cast;
   }
   if (caster === false) {
-    caster = v => {
-      if (typeof v !== 'number') {
-        throw new Error();
-      }
-      return v;
-    };
+    caster = this._defaultCaster;
   }
   this._cast = caster;
 
   return this._cast;
 };
 
+/*!
+ * ignore
+ */
+
+SchemaNumber._defaultCaster = v => {
+  if (typeof v !== 'number') {
+    throw new Error();
+  }
+  return v;
+};
+
 /**
  * This schema type's name, to defend against minifiers that mangle
  * function names.
@@ -375,9 +381,15 @@ SchemaNumber.prototype.cast = function(value, doc, init) {
     value._id : // documents
     value;
 
-  const castNumber = typeof this.constructor.cast === 'function' ?
-    this.constructor.cast() :
-    SchemaNumber.cast();
+  let castNumber;
+  if (typeof this._castFunction === 'function') {
+    castNumber = this._castFunction;
+  } else if (typeof this.constructor.cast === 'function') {
+    castNumber = this.constructor.cast();
+  } else {
+    castNumber = SchemaNumber.cast();
+  }
+
   try {
     return castNumber(val);
   } catch (err) {
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index ee27f2ea20a..fb07c149bbd 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -151,18 +151,24 @@ ObjectId.cast = function cast(caster) {
     return this._cast;
   }
   if (caster === false) {
-    caster = v => {
-      if (!(v instanceof oid)) {
-        throw new Error(v + ' is not an instance of ObjectId');
-      }
-      return v;
-    };
+    caster = this._defaultCaster;
   }
   this._cast = caster;
 
   return this._cast;
 };
 
+/*!
+ * ignore
+ */
+
+ObjectId._defaultCaster = v => {
+  if (!(v instanceof oid)) {
+    throw new Error(v + ' is not an instance of ObjectId');
+  }
+  return v;
+};
+
 /**
  * Override the function the required validator uses to check whether a string
  * passes the `required` check.
@@ -260,9 +266,15 @@ ObjectId.prototype.cast = function(value, doc, init) {
     return ret;
   }
 
-  const castObjectId = typeof this.constructor.cast === 'function' ?
-    this.constructor.cast() :
-    ObjectId.cast();
+  let castObjectId;
+  if (typeof this._castFunction === 'function') {
+    castObjectId = this._castFunction;
+  } else if (typeof this.constructor.cast === 'function') {
+    castObjectId = this.constructor.cast();
+  } else {
+    castObjectId = ObjectId.cast();
+  }
+
   try {
     return castObjectId(value);
   } catch (error) {
diff --git a/lib/schema/string.js b/lib/schema/string.js
index a3bfaf4ea57..7b83a8bc863 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -86,18 +86,24 @@ SchemaString.cast = function cast(caster) {
     return this._cast;
   }
   if (caster === false) {
-    caster = v => {
-      if (v != null && typeof v !== 'string') {
-        throw new Error();
-      }
-      return v;
-    };
+    caster = this._defaultCaster;
   }
   this._cast = caster;
 
   return this._cast;
 };
 
+/*!
+ * ignore
+ */
+
+SchemaString._defaultCaster = v => {
+  if (v != null && typeof v !== 'string') {
+    throw new Error();
+  }
+  return v;
+};
+
 /**
  * Attaches a getter for all String instances.
  *
@@ -601,9 +607,15 @@ SchemaString.prototype.cast = function(value, doc, init) {
     return ret;
   }
 
-  const castString = typeof this.constructor.cast === 'function' ?
-    this.constructor.cast() :
-    SchemaString.cast();
+  let castString;
+  if (typeof this._castFunction === 'function') {
+    castString = this._castFunction;
+  } else if (typeof this.constructor.cast === 'function') {
+    castString = this.constructor.cast();
+  } else {
+    castString = SchemaString.cast();
+  }
+
   try {
     return castString(value);
   } catch (error) {
diff --git a/lib/schematype.js b/lib/schematype.js
index af813753b18..6404f6d697a 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -75,6 +75,7 @@ function SchemaType(path, options, instance) {
   const keys = Object.keys(this.options);
   for (const prop of keys) {
     if (prop === 'cast') {
+      this.castFunction(this.options[prop]);
       continue;
     }
     if (utils.hasUserDefinedProperty(this.options, prop) && typeof this[prop] === 'function') {
@@ -157,6 +158,40 @@ SchemaType.cast = function cast(caster) {
   return this._cast;
 };
 
+/**
+ * Get/set the function used to cast arbitrary values to this particular schematype instance.
+ * Overrides `SchemaType.cast()`.
+ *
+ * ####Example:
+ *
+ *     // Disallow `null` for numbers, and don't try to cast any values to
+ *     // numbers, so even strings like '123' will cause a CastError.
+ *     const number = new mongoose.Number('mypath', {});
+ *     number.cast(function(v) {
+ *       assert.ok(v === undefined || typeof v === 'number');
+ *       return v;
+ *     });
+ *
+ * @param {Function|false} caster Function that casts arbitrary values to this type, or throws an error if casting failed
+ * @return {Function}
+ * @static
+ * @receiver SchemaType
+ * @function cast
+ * @api public
+ */
+
+SchemaType.prototype.castFunction = function castFunction(caster) {
+  if (arguments.length === 0) {
+    return this._castFunction;
+  }
+  if (caster === false) {
+    caster = this.constructor._defaultCaster || (v => v);
+  }
+  this._castFunction = caster;
+
+  return this._castFunction;
+};
+
 /**
  * Sets a default option for this schema type.
  *
diff --git a/test/schema.test.js b/test/schema.test.js
index 33a86dcfea3..31ab92ac4be 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2506,4 +2506,52 @@ describe('schema', function() {
     const casted = schema.path('ids').cast([[]]);
     assert.equal(casted[0].$path(), 'ids.$');
   });
+
+  describe('cast option (gh-8407)', function() {
+    it('disable casting using `false`', function() {
+      const schema = Schema({
+        myId: { type: 'ObjectId', cast: false },
+        myNum: { type: 'number', cast: false },
+        myDate: { type: Date, cast: false },
+        myBool: { type: Boolean, cast: false },
+        myStr: { type: String, cast: false }
+      });
+
+      assert.throws(() => schema.path('myId').cast('12charstring'), /Cast to ObjectId failed/);
+      assert.throws(() => schema.path('myNum').cast('foo'), /Cast to Number failed/);
+      assert.throws(() => schema.path('myDate').cast('2012'), /Cast to date failed/);
+      assert.throws(() => schema.path('myBool').cast('true'), /Cast to Boolean failed/);
+      assert.throws(() => schema.path('myStr').cast(55), /Cast to string failed/);
+
+      schema.path('myId').cast(new mongoose.Types.ObjectId());
+      schema.path('myNum').cast(42);
+      schema.path('myDate').cast(new Date());
+      schema.path('myBool').cast(false);
+      schema.path('myStr').cast('Hello, World');
+    });
+
+    it('custom casters', function() {
+      const schema = Schema({
+        myId: {
+          type: 'ObjectId',
+          cast: v => new mongoose.Types.ObjectId(v)
+        },
+        myNum: {
+          type: 'number',
+          cast: v => Math.ceil(v)
+        },
+        myDate: { type: Date, cast: v => new Date(v) },
+        myBool: { type: Boolean, cast: v => !!v },
+        myStr: { type: String, cast: v => '' + v }
+      });
+
+      assert.equal(schema.path('myId').cast('12charstring').toHexString(), '313263686172737472696e67');
+      assert.equal(schema.path('myNum').cast(3.14), 4);
+      assert.equal(schema.path('myDate').cast('2012-06-01').getFullYear(), 2012);
+      assert.equal(schema.path('myBool').cast('hello'), true);
+      assert.equal(schema.path('myStr').cast(42), '42');
+
+      assert.throws(() => schema.path('myId').cast('bad'), /Cast to ObjectId failed/);
+    });
+  });
 });

From c25169702ccc2a8f8123853453ed755f17278ce7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Nov 2020 14:58:16 -0500
Subject: [PATCH 1307/2348] docs(ssl): add note about `ssl` defaulting to
 `true` for srv connection strings

Re: #9511
---
 docs/tutorials/ssl.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/docs/tutorials/ssl.md b/docs/tutorials/ssl.md
index 1c188f78903..4595c2a29dd 100644
--- a/docs/tutorials/ssl.md
+++ b/docs/tutorials/ssl.md
@@ -9,6 +9,9 @@ mongoose.connect('mongodb://localhost:27017/test', { ssl: true });
 mongoose.connect('mongodb://localhost:27017/test?ssl=true');
 ```
 
+The `ssl` option defaults to `false` for connection strings that start with `mongodb://`. However,
+the `ssl` option defaults to `true` for connection strings that start with `mongodb+srv://`. So if you are using an srv connection string to connect to [MongoDB Atlas](https://www.mongodb.com/cloud/atlas), SSL is enabled by default.
+
 If you try to connect to a MongoDB cluster that requires SSL without enabling the `ssl` option, `mongoose.connect()`
 will error out with the below error:
 
@@ -64,4 +67,4 @@ MongooseServerSelectionError: Hostname/IP does not match certificate's altnames:
 ```
 
 The SSL certificate's [common name](https://knowledge.digicert.com/solution/SO7239.html) **must** line up with the host name
-in your connection string. If the SSL certificate is for `hostname2.mydomain.com`, your connection string must connect to `hostname2.mydomain.com`, not any other hostname or IP address that may be equivalent to `hostname2.mydomain.com`. For replica sets, this also means that the SSL certificate's common name must line up with the [machine's `hostname`](/docs/connections.html#replicaset-hostnames).
\ No newline at end of file
+in your connection string. If the SSL certificate is for `hostname2.mydomain.com`, your connection string must connect to `hostname2.mydomain.com`, not any other hostname or IP address that may be equivalent to `hostname2.mydomain.com`. For replica sets, this also means that the SSL certificate's common name must line up with the [machine's `hostname`](/docs/connections.html#replicaset-hostnames).

From 88ea4f41635011d1171a4cd35e4caa8df4476127 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Nov 2020 18:58:56 -0500
Subject: [PATCH 1308/2348] fix(error): throw more helpful error when
 connecting to a non-SSL MongoDB server with SSL enabled

Fix #9511
---
 lib/error/serverSelection.js       | 18 +++++++++++++++---
 lib/helpers/topology/isSSLError.js | 15 +++++++++++++++
 2 files changed, 30 insertions(+), 3 deletions(-)
 create mode 100644 lib/helpers/topology/isSSLError.js

diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index 464abf04880..880dd9c017f 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -7,6 +7,7 @@
 const MongooseError = require('./mongooseError');
 const allServersUnknown = require('../helpers/topology/allServersUnknown');
 const isAtlas = require('../helpers/topology/isAtlas');
+const isSSLError = require('../helpers/topology/isSSLError');
 
 /*!
  * ignore
@@ -17,6 +18,11 @@ const atlasMessage = 'Could not connect to any servers in your MongoDB Atlas clu
   'an IP that isn\'t whitelisted. Make sure your current IP address is on your Atlas ' +
   'cluster\'s IP whitelist: https://docs.atlas.mongodb.com/security-whitelist/';
 
+const sslMessage = 'Mongoose is connecting with SSL enabled, but the server is ' +
+  'not accepting SSL connections. Please ensure that the MongoDB server you are ' +
+  'connecting to is configured to accept SSL connections. Learn more: ' +
+  'https://mongoosejs.com/docs/tutorials/ssl.html';
+
 class MongooseServerSelectionError extends MongooseError {
   /**
    * MongooseServerSelectionError constructor
@@ -30,9 +36,15 @@ class MongooseServerSelectionError extends MongooseError {
       allServersUnknown(reason) &&
       err.message.indexOf('bad auth') === -1 &&
       err.message.indexOf('Authentication failed') === -1;
-    this.message = isAtlasWhitelistError ?
-      atlasMessage :
-      err.message;
+
+    console.log('AA', reason);
+    if (isAtlasWhitelistError) {
+      this.message = atlasMessage;
+    } else if (isSSLError(reason)) {
+      this.message = sslMessage;
+    } else {
+      this.message = err.message;
+    }
     for (const key in err) {
       if (key !== 'name') {
         this[key] = err[key];
diff --git a/lib/helpers/topology/isSSLError.js b/lib/helpers/topology/isSSLError.js
new file mode 100644
index 00000000000..61e57d1d286
--- /dev/null
+++ b/lib/helpers/topology/isSSLError.js
@@ -0,0 +1,15 @@
+'use strict';
+
+const nonSSLMessage = 'Client network socket disconnected before secure TLS ' +
+  'connection was established';
+
+module.exports = function isSSLError(topologyDescription) {
+  if (topologyDescription == null ||
+    topologyDescription.constructor.name !== 'TopologyDescription') {
+    return false;
+  }
+
+  const descriptions = Array.from(topologyDescription.servers.values());
+  return descriptions.length > 0 &&
+    descriptions.every(descr => descr.error && descr.error.message.indexOf(nonSSLMessage) !== -1);
+};
\ No newline at end of file

From 9892367113caea3d9dd1bd57180b7f182cf8881f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 3 Nov 2020 19:27:27 -0500
Subject: [PATCH 1309/2348] chore: remove unnecessary print statement

---
 lib/collection.js            | 10 ++--------
 lib/connection.js            | 22 ++++++++++++++++++++--
 lib/error/serverSelection.js |  1 -
 3 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/lib/collection.js b/lib/collection.js
index 97f5bb3238e..1f60a630dcc 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -263,7 +263,6 @@ Collection.prototype.watch = function() {
  */
 
 Collection.prototype._shouldBufferCommands = function _shouldBufferCommands() {
-  const conn = this.conn;
   const opts = this.opts;
 
   if (opts.bufferCommands != null) {
@@ -272,13 +271,8 @@ Collection.prototype._shouldBufferCommands = function _shouldBufferCommands() {
   if (opts && opts.schemaUserProvidedOptions != null && opts.schemaUserProvidedOptions.bufferCommands != null) {
     return opts.schemaUserProvidedOptions.bufferCommands;
   }
-  if (conn.config.bufferCommands != null) {
-    return conn.config.bufferCommands;
-  }
-  if (conn.base != null && conn.base.get('bufferCommands') != null) {
-    return conn.base.get('bufferCommands');
-  }
-  return true;
+
+  return this.conn._shouldBufferCommands();
 };
 
 /*!
diff --git a/lib/connection.js b/lib/connection.js
index 9ff91531583..2d2e7fde818 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -549,20 +549,38 @@ function _wrapConnHelper(fn) {
       // as long as `mongoose.connect()` is called on the same tick.
       // Re: gh-8534
       immediate(() => {
-        if (this.readyState === STATES.connecting) {
+        if (this.readyState === STATES.connecting && this._shouldBufferCommands()) {
           this.once('open', function() {
             fn.apply(this, argsWithoutCb.concat([cb]));
           });
         } else if (this.readyState === STATES.disconnected && this.db == null) {
           cb(disconnectedError);
         } else {
-          fn.apply(this, argsWithoutCb.concat([cb]));
+          try {
+            fn.apply(this, argsWithoutCb.concat([cb]));
+          } catch (err) {
+            return cb(err);
+          }
         }
       });
     });
   };
 }
 
+/*!
+ * ignore
+ */
+
+Connection.prototype._shouldBufferCommands = function _shouldBufferCommands() {
+  if (this.config.bufferCommands != null) {
+    return this.config.bufferCommands;
+  }
+  if (this.base != null && this.base.get('bufferCommands') != null) {
+    return this.base.get('bufferCommands');
+  }
+  return true;
+};
+
 /**
  * error
  *
diff --git a/lib/error/serverSelection.js b/lib/error/serverSelection.js
index 880dd9c017f..162e2fceb43 100644
--- a/lib/error/serverSelection.js
+++ b/lib/error/serverSelection.js
@@ -37,7 +37,6 @@ class MongooseServerSelectionError extends MongooseError {
       err.message.indexOf('bad auth') === -1 &&
       err.message.indexOf('Authentication failed') === -1;
 
-    console.log('AA', reason);
     if (isAtlasWhitelistError) {
       this.message = atlasMessage;
     } else if (isSSLError(reason)) {

From ad5fb7fd8577a23de47035826942adcbc48eb73f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 3 Nov 2020 20:25:17 -0500
Subject: [PATCH 1310/2348] feat(document): add `$parent()` as an alias for
 `parent()` for documents and subdocuments to avoid path name conflicts

Fix #9455
---
 lib/document.js                | 12 +++++++++
 lib/schema/SingleNestedPath.js |  2 +-
 lib/schematype.js              |  2 +-
 lib/types/embedded.js          | 16 +++++++++---
 lib/types/subdocument.js       | 46 ++++++++++++++++++++--------------
 test/document.test.js          |  2 +-
 test/model.populate.test.js    |  5 ++++
 7 files changed, 59 insertions(+), 26 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 50a05e7afbd..625909f85bb 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3650,6 +3650,18 @@ Document.prototype.parent = function() {
   return this.$__.parent;
 };
 
+/**
+ * Alias for `parent()`. If this document is a subdocument or populated
+ * document, returns the document's parent. Returns `undefined` otherwise.
+ *
+ * @api public
+ * @method $parent
+ * @memberOf Document
+ * @instance
+ */
+
+Document.prototype.$parent = Document.prototype.parent;
+
 /**
  * Helper for console.log
  *
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index d0108ee0e61..5024728046a 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -62,7 +62,7 @@ function _createConstructor(schema, baseClass) {
   const _embedded = function SingleNested(value, path, parent) {
     const _this = this;
 
-    this.$parent = parent;
+    this.$__parent = parent;
     Subdocument.apply(this, arguments);
 
     this.$session(this.ownerDocument().$session());
diff --git a/lib/schematype.js b/lib/schematype.js
index 6404f6d697a..3cd297c46f2 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1038,7 +1038,7 @@ SchemaType.prototype.getDefault = function(scope, init) {
 
     const casted = this.applySetters(ret, scope, init);
     if (casted && casted.$isSingleNested) {
-      casted.$parent = scope;
+      casted.$__parent = scope;
     }
     return casted;
   }
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 18a977847ae..c2d9f609900 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -370,8 +370,8 @@ EmbeddedDocument.prototype.ownerDocument = function() {
     return this;
   }
 
-  while (parent[documentArrayParent] || parent.$parent) {
-    parent = parent[documentArrayParent] || parent.$parent;
+  while (parent[documentArrayParent] || parent.$__parent) {
+    parent = parent[documentArrayParent] || parent.$__parent;
   }
 
   this.$__.ownerDocument = parent;
@@ -397,13 +397,13 @@ EmbeddedDocument.prototype.$__fullPath = function(path) {
     }
 
     const paths = [];
-    while (parent[documentArrayParent] || parent.$parent) {
+    while (parent[documentArrayParent] || parent.$__parent) {
       if (parent[documentArrayParent]) {
         paths.unshift(parent.__parentArray.$path());
       } else {
         paths.unshift(parent.$basePath);
       }
-      parent = parent[documentArrayParent] || parent.$parent;
+      parent = parent[documentArrayParent] || parent.$__parent;
     }
 
     this.$__.fullPath = paths.join('.');
@@ -429,6 +429,14 @@ EmbeddedDocument.prototype.parent = function() {
   return this[documentArrayParent];
 };
 
+/**
+ * Returns this sub-documents parent document.
+ *
+ * @api public
+ */
+
+EmbeddedDocument.prototype.$parent = EmbeddedDocument.prototype.parent;
+
 /**
  * Returns this sub-documents parent array.
  *
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index d6494ffffeb..e2693054ab7 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -111,8 +111,8 @@ Subdocument.prototype.$__save = function(fn) {
 };
 
 Subdocument.prototype.$isValid = function(path) {
-  if (this.$parent && this.$basePath) {
-    return this.$parent.$isValid([this.$basePath, path].join('.'));
+  if (this.$__parent && this.$basePath) {
+    return this.$__parent.$isValid([this.$basePath, path].join('.'));
   }
   return Document.prototype.$isValid.call(this, path);
 };
@@ -120,24 +120,24 @@ Subdocument.prototype.$isValid = function(path) {
 Subdocument.prototype.markModified = function(path) {
   Document.prototype.markModified.call(this, path);
 
-  if (this.$parent && this.$basePath) {
-    if (this.$parent.isDirectModified(this.$basePath)) {
+  if (this.$__parent && this.$basePath) {
+    if (this.$__parent.isDirectModified(this.$basePath)) {
       return;
     }
-    this.$parent.markModified([this.$basePath, path].join('.'), this);
+    this.$__parent.markModified([this.$basePath, path].join('.'), this);
   }
 };
 
 Subdocument.prototype.isModified = function(paths, modifiedPaths) {
-  if (this.$parent && this.$basePath) {
+  if (this.$__parent && this.$basePath) {
     if (Array.isArray(paths) || typeof paths === 'string') {
       paths = (Array.isArray(paths) ? paths : paths.split(' '));
       paths = paths.map(p => [this.$basePath, p].join('.'));
 
-      return this.$parent.isModified(paths, modifiedPaths);
+      return this.$__parent.isModified(paths, modifiedPaths);
     }
 
-    return this.$parent.isModified(this.$basePath);
+    return this.$__parent.isModified(this.$basePath);
   }
 
   return Document.prototype.isModified.call(this, paths, modifiedPaths);
@@ -154,8 +154,8 @@ Subdocument.prototype.isModified = function(paths, modifiedPaths) {
 
 Subdocument.prototype.$markValid = function(path) {
   Document.prototype.$markValid.call(this, path);
-  if (this.$parent && this.$basePath) {
-    this.$parent.$markValid([this.$basePath, path].join('.'));
+  if (this.$__parent && this.$basePath) {
+    this.$__parent.$markValid([this.$basePath, path].join('.'));
   }
 };
 
@@ -171,8 +171,8 @@ Subdocument.prototype.invalidate = function(path, err, val) {
     Document.prototype.invalidate.call(this, path, err, val);
   }
 
-  if (this.$parent && this.$basePath) {
-    this.$parent.invalidate([this.$basePath, path].join('.'), err, val);
+  if (this.$__parent && this.$basePath) {
+    this.$__parent.invalidate([this.$basePath, path].join('.'), err, val);
   } else if (err.kind === 'cast' || err.name === 'CastError') {
     throw err;
   }
@@ -186,8 +186,8 @@ Subdocument.prototype.invalidate = function(path, err, val) {
 
 Subdocument.prototype.$ignore = function(path) {
   Document.prototype.$ignore.call(this, path);
-  if (this.$parent && this.$basePath) {
-    this.$parent.$ignore([this.$basePath, path].join('.'));
+  if (this.$__parent && this.$basePath) {
+    this.$__parent.$ignore([this.$basePath, path].join('.'));
   }
 };
 
@@ -202,13 +202,13 @@ Subdocument.prototype.ownerDocument = function() {
     return this.$__.ownerDocument;
   }
 
-  let parent = this.$parent;
+  let parent = this.$__parent;
   if (!parent) {
     return this;
   }
 
-  while (parent.$parent || parent[documentArrayParent]) {
-    parent = parent.$parent || parent[documentArrayParent];
+  while (parent.$__parent || parent[documentArrayParent]) {
+    parent = parent.$__parent || parent[documentArrayParent];
   }
 
   this.$__.ownerDocument = parent;
@@ -222,9 +222,17 @@ Subdocument.prototype.ownerDocument = function() {
  */
 
 Subdocument.prototype.parent = function() {
-  return this.$parent;
+  return this.$__parent;
 };
 
+/**
+ * Returns this sub-documents parent document.
+ *
+ * @api public
+ */
+
+Subdocument.prototype.$parent = Subdocument.prototype.parent;
+
 /*!
  * no-op for hooks
  */
@@ -250,7 +258,7 @@ Subdocument.prototype.remove = function(options, callback) {
 
   // If removing entire doc, no need to remove subdoc
   if (!options || !options.noop) {
-    this.$parent.set(this.$basePath, null);
+    this.$__parent.set(this.$basePath, null);
   }
 
   if (typeof callback === 'function') {
diff --git a/test/document.test.js b/test/document.test.js
index 0629ff67791..4e4133ae212 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -3315,7 +3315,7 @@ describe('document', function() {
       const Parent = db.model('Parent', ParentSchema);
 
       const p = new Parent();
-      assert.equal(p.child.$parent, p);
+      assert.equal(p.child.$parent(), p);
     });
 
     it('removing parent doc calls remove hooks on subdocs (gh-2348) (gh-4566)', function(done) {
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 1e0e335e32f..cae7093e49a 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9651,19 +9651,24 @@ describe('model: populate:', function() {
 
       let doc = yield Parent.findOne().populate('single');
       assert.ok(doc.single.parent() === doc);
+      assert.ok(doc.single.$parent() === doc);
 
       doc = yield Parent.findOne().populate('arr');
       assert.ok(doc.arr[0].parent() === doc);
+      assert.ok(doc.arr[0].$parent() === doc);
 
       doc = yield Parent.findOne().populate('docArr.ref');
       assert.ok(doc.docArr[0].ref.parent() === doc);
+      assert.ok(doc.docArr[0].ref.$parent() === doc);
 
       doc = yield Parent.findOne().populate('myVirtual');
       assert.ok(doc.myVirtual.parent() === doc);
+      assert.ok(doc.myVirtual.$parent() === doc);
 
       doc = yield Parent.findOne();
       yield doc.populate('single').execPopulate();
       assert.ok(doc.single.parent() === doc);
+      assert.ok(doc.single.$parent() === doc);
     });
   });
 

From 4abfb9557ab9715bff1819010e699f0f58c0ebac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Nov 2020 15:08:55 -0500
Subject: [PATCH 1311/2348] chore: release 5.10.12

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 5bdf39eedf8..3d10eb7e52c 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.10.12 / 2020-11-04
+====================
+ * fix(connection): catch and report sync errors in connection wrappers like `startSession()` #9515
+ * fix(document): ignore getters when diffing values for change tracking #9501
+ * fix(connection): avoid executing promise handler unless it's a function #9507 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(error): throw more helpful error when connecting to a non-SSL MongoDB server with SSL enabled #9511
+ * docs(model+query): clarify that `deleteOne` and `deleteMany` trigger middleware #9504
+ * docs(ssl): add note about `ssl` defaulting to `true` for srv connection strings #9511
+
 5.10.11 / 2020-10-26
 ====================
  * fix(connection): when calling `mongoose.connect()` multiple times in parallel, make 2nd call wait for connection before resolving #9476
diff --git a/package.json b/package.json
index 1b064cdcd4f..58f8e4b138d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.11",
+  "version": "5.10.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a45cadaa0cb74507e09a9f80d003ac96b4e6253a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Nov 2020 19:57:22 -0500
Subject: [PATCH 1312/2348] feat(model+query): allow defining middleware for
 all query methods or all document methods, but not other middleware types

Fix #9190
---
 lib/helpers/model/applyHooks.js           |  3 +++
 lib/helpers/query/applyQueryMiddleware.js |  3 +++
 test/document.test.js                     | 33 +++++++++++++++++++++++
 test/query.middleware.test.js             | 30 +++++++++++++++++++++
 4 files changed, 69 insertions(+)

diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index 9570a368e79..3de782c6dea 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -78,6 +78,9 @@ function applyHooks(model, schema, options) {
       if (hook.name === 'remove' || hook.name === 'init') {
         return hook['document'] == null || !!hook['document'];
       }
+      if (hook.query != null || hook.document != null) {
+        return !!hook.document;
+      }
       return true;
     }).
     filter(hook => {
diff --git a/lib/helpers/query/applyQueryMiddleware.js b/lib/helpers/query/applyQueryMiddleware.js
index a08baf87ff3..792975836e3 100644
--- a/lib/helpers/query/applyQueryMiddleware.js
+++ b/lib/helpers/query/applyQueryMiddleware.js
@@ -56,6 +56,9 @@ function applyQueryMiddleware(Query, model) {
     if (hook.name === 'validate' || hook.name === 'remove') {
       return !!contexts.query;
     }
+    if (hook.query != null || hook.document != null) {
+      return !!hook.query;
+    }
     return true;
   });
 
diff --git a/test/document.test.js b/test/document.test.js
index 4e4133ae212..51f267dd7b5 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9614,4 +9614,37 @@ describe('document', function() {
       assert.equal(fromDb.taxPercent, 10);
     });
   });
+
+  it('allows defining middleware for all document hooks using regexp (gh-9190)', function() {
+    const schema = Schema({ name: String });
+
+    let called = 0;
+    schema.pre(/.*/, { document: true, query: false }, function() {
+      ++called;
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      yield Model.find();
+      assert.equal(called, 0);
+
+      yield Model.findOne();
+      assert.equal(called, 0);
+
+      yield Model.countDocuments();
+      assert.equal(called, 0);
+
+      const docs = yield Model.create([{ name: 'test' }], { validateBeforeSave: false });
+      assert.equal(called, 1);
+
+      yield docs[0].validate();
+      assert.equal(called, 2);
+
+      yield docs[0].updateOne({ name: 'test2' });
+      assert.equal(called, 3);
+
+      yield Model.aggregate([{ $match: { name: 'test' } }]);
+      assert.equal(called, 3);
+    });
+  });
 });
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index a45ab720158..af7486eb125 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -637,4 +637,34 @@ describe('query middleware', function() {
       assert.equal(docs.length, 1);
     });
   });
+
+  it('allows registering middleware for all queries with regexp (gh-9190)', function() {
+    const schema = Schema({ name: String });
+
+    let called = 0;
+    schema.pre(/.*/, { query: true }, function() {
+      ++called;
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      yield Model.find();
+      assert.equal(called, 1);
+
+      yield Model.findOne();
+      assert.equal(called, 2);
+
+      yield Model.countDocuments();
+      assert.equal(called, 3);
+
+      yield Model.create({ name: 'test' });
+      assert.equal(called, 3);
+
+      yield Model.insertMany([{ name: 'test' }]);
+      assert.equal(called, 3);
+
+      yield Model.aggregate([{ $match: { name: 'test' } }]);
+      assert.equal(called, 3);
+    });
+  });
 });

From d66624a490f1ae15aab71274ce83aefe77fc1173 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Nov 2020 20:23:38 -0500
Subject: [PATCH 1313/2348] test: fix tests re: #9190

---
 lib/helpers/model/applyHooks.js | 2 +-
 test/query.middleware.test.js   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/model/applyHooks.js b/lib/helpers/model/applyHooks.js
index 3de782c6dea..0498c75e665 100644
--- a/lib/helpers/model/applyHooks.js
+++ b/lib/helpers/model/applyHooks.js
@@ -79,7 +79,7 @@ function applyHooks(model, schema, options) {
         return hook['document'] == null || !!hook['document'];
       }
       if (hook.query != null || hook.document != null) {
-        return !!hook.document;
+        return hook.document !== false;
       }
       return true;
     }).
diff --git a/test/query.middleware.test.js b/test/query.middleware.test.js
index af7486eb125..755222785af 100644
--- a/test/query.middleware.test.js
+++ b/test/query.middleware.test.js
@@ -642,7 +642,7 @@ describe('query middleware', function() {
     const schema = Schema({ name: String });
 
     let called = 0;
-    schema.pre(/.*/, { query: true }, function() {
+    schema.pre(/.*/, { query: true, document: false }, function() {
       ++called;
     });
     const Model = db.model('Test', schema);

From 4dad667a04c4d8c6bad918a5169203ed13eb5ce9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 4 Nov 2020 21:25:40 -0500
Subject: [PATCH 1314/2348] feat(QueryCursor): execute post find hooks for each
 doc in query cursor

Fix #9345
---
 lib/cursor/QueryCursor.js | 27 ++++++++++++++++++++++-----
 test/query.cursor.test.js | 22 ++++++++++++++++++++++
 2 files changed, 44 insertions(+), 5 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 70bb6179a24..32a130f7d7d 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -16,8 +16,8 @@ const util = require('util');
  * in addition to several other mechanisms for loading documents from MongoDB
  * one at a time.
  *
- * QueryCursors execute the model's pre find hooks, but **not** the model's
- * post find hooks.
+ * QueryCursors execute the model's pre `find` hooks before loading any documents
+ * from MongoDB, and the model's post `find` hooks after loading each document.
  *
  * Unless you're an advanced user, do **not** instantiate this class directly.
  * Use [`Query#cursor()`](/docs/api.html#query_Query-cursor) instead.
@@ -440,9 +440,26 @@ function _populateBatch() {
  */
 
 function _nextDoc(ctx, doc, pop, callback) {
-  return ctx.query._mongooseOptions.lean ?
-    callback(null, doc) :
-    _create(ctx, doc, pop, callback);
+  if (ctx.query._mongooseOptions.lean) {
+    return ctx.model.hooks.execPost('find', ctx.query, [doc], err => {
+      if (err != null) {
+        return callback(err);
+      }
+      callback(null, doc);
+    });
+  }
+
+  _create(ctx, doc, pop, (err, doc) => {
+    if (err != null) {
+      return callback(err);
+    }
+    ctx.model.hooks.execPost('find', ctx.query, [doc], err => {
+      if (err != null) {
+        return callback(err);
+      }
+      callback(null, doc);
+    });
+  });
 }
 
 /*!
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 639ceac399f..5fde51466cd 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -689,4 +689,26 @@ describe('QueryCursor', function() {
       assert.deepEqual(docsWithIndexes, expected);
     });
   });
+
+  it('post hooks (gh-9435)', function() {
+    const schema = new mongoose.Schema({ name: String });
+    schema.post('find', function(doc) {
+      doc.name = doc.name.toUpperCase();
+    });
+    const Movie = db.model('Movie', schema);
+
+    return co(function*() {
+      yield Movie.deleteMany({});
+      yield Movie.create([
+        { name: 'Kickboxer' },
+        { name: 'Ip Man' },
+        { name: 'Enter the Dragon' }
+      ]);
+
+      const arr = [];
+      yield Movie.find().sort({ name: -1 }).cursor().
+        eachAsync(doc => arr.push(doc.name));
+      assert.deepEqual(arr, ['KICKBOXER', 'IP MAN', 'ENTER THE DRAGON']);
+    });
+  });
 });

From f48a13b7b0b723011ed71523e96f28235412579e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Nov 2020 13:01:21 -0500
Subject: [PATCH 1315/2348] test(document): repro #9519

---
 test/document.test.js | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 291eb96fa0a..e935846d881 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9556,4 +9556,46 @@ describe('document', function() {
       assert.equal(fromDb.taxPercent, 10);
     });
   });
+
+  it('correctly handles setting nested props to other nested props (gh-9519)', function() {
+    const schemaA = Schema({
+      propX: {
+        nested1: { prop: Number },
+        nested2: { prop: Number },
+        nested3: { prop: Number }
+      },
+      propY: {
+        nested1: { prop: Number },
+        nested2: { prop: Number },
+        nested3: { prop: Number }
+      }
+    });
+
+    const schemaB = Schema({ prop: { prop: Number } });
+
+    const ModelA = db.model('Test1', schemaA);
+    const ModelB = db.model('Test2', schemaB);
+
+    return co(function*() {
+      const saved = yield ModelA.create({
+        propX: {
+          nested1: { prop: 1 },
+          nested2: { prop: 1 },
+          nested3: { prop: 1 }
+        },
+        propY: {
+          nested1: { prop: 2 },
+          nested2: { prop: 2 },
+          nested3: { prop: 2 }
+        }
+      });
+
+      const objA = yield ModelA.findById(saved._id);
+      const objB = new ModelB();
+
+      objB.prop = objA.propX.nested1;
+
+      assert.strictEqual(objB.prop.prop, 1);
+    });
+  });
 });

From 50835c48e933f656e0a118ea7e9a093738fc66ee Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Nov 2020 13:01:34 -0500
Subject: [PATCH 1316/2348] fix(document): correctly handle setting props to
 other nested props

Fix #9519
---
 lib/helpers/document/compile.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index 1a2a0357d8b..def45e67b23 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -92,6 +92,17 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
             }
           });
 
+          Object.defineProperty(nested, '$__get', {
+            enumerable: false,
+            configurable: true,
+            writable: false,
+            value: function() {
+              return _this.get(path, null, {
+                virtuals: get(this, 'schema.options.toObject.virtuals', null)
+              });
+            }
+          });
+
           Object.defineProperty(nested, 'toJSON', {
             enumerable: false,
             configurable: true,
@@ -142,7 +153,7 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
         if (v != null && v.$__isNested) {
           // Convert top-level to POJO, but leave subdocs hydrated so `$set`
           // can handle them. See gh-9293.
-          v = v.$__parent.get(path);
+          v = v.$__get();
         } else if (v instanceof Document && !v.$__isNested) {
           v = v.toObject(internalToObjectOptions);
         }

From 7e4f7b937ddb149b87a293c7648f8facce68b620 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Nov 2020 19:21:23 -0500
Subject: [PATCH 1317/2348] test(update): repro #9518

---
 test/model.update.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 7102679301c..4339746195b 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3544,4 +3544,28 @@ describe('model: updateOne: ', function() {
       assert.ok(!err.errors['nested']);
     });
   });
+
+  it('handles spread docs (gh-9518)', function() {
+    const schema = new mongoose.Schema({
+      name: String,
+      children: [{ name: String }]
+    });
+
+    const Person = db.model('Person', schema);
+
+    return co(function*() {
+      const doc = yield Person.create({
+        name: 'Anakin',
+        children: [{ name: 'Luke' }]
+      });
+
+      doc.children[0].name = 'Luke Skywalker';
+      const update = { 'children.0': Object.assign({}, doc.children[0]) };
+
+      yield Person.updateOne({ _id: doc._id }, update);
+
+      const fromDb = yield Person.findById(doc);
+      assert.equal(fromDb.children[0].name, 'Luke Skywalker');
+    });
+  });
 });
\ No newline at end of file

From f27a698646af117ae6a2a694c78e150364476f40 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Nov 2020 19:25:24 -0500
Subject: [PATCH 1318/2348] fix: correctly handle spread docs when merging
 update with `updateOne()`

Re: #9518
---
 lib/helpers/clone.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/helpers/clone.js b/lib/helpers/clone.js
index c93a17fbdf2..5f0b2c92960 100644
--- a/lib/helpers/clone.js
+++ b/lib/helpers/clone.js
@@ -10,6 +10,7 @@ const getFunctionName = require('./getFunctionName');
 const isBsonType = require('./isBsonType');
 const isObject = require('./isObject');
 const symbols = require('./symbols');
+const utils = require('../utils');
 
 
 /*!
@@ -42,6 +43,10 @@ function clone(obj, options, isArrayChild) {
       options = Object.assign({}, options, { getters: false });
     }
 
+    if (utils.isPOJO(obj) && obj.$__ != null && obj._doc != null) {
+      return obj._doc;
+    }
+
     if (options && options.json && typeof obj.toJSON === 'function') {
       return obj.toJSON(options);
     }

From 50919ee3be1ef7522fb805500a30eeb3a2bc4bc0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Nov 2020 20:54:01 -0500
Subject: [PATCH 1319/2348] feat(document): support array and space-delimited
 syntax for `isDirectModified()`

Re: #9474
---
 lib/document.js                | 20 ++++++++++++++++++--
 test/document.modified.test.js |  2 ++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 625909f85bb..8b071b3d67e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1975,13 +1975,29 @@ Document.prototype.$isDeleted = function(val) {
  *     doc.isDirectModified('documents.0.title') // true
  *     doc.isDirectModified('documents') // false
  *
- * @param {String} path
+ * @param {String|Array<String>} path
  * @return {Boolean}
  * @api public
  */
 
 Document.prototype.isDirectModified = function(path) {
-  return (path in this.$__.activePaths.states.modify);
+  if (path == null) {
+    return this.$__.activePaths.some('modify');
+  }
+
+  let paths = path;
+  if (!Array.isArray(paths)) {
+    paths = paths.split(' ');
+  }
+
+  if (paths.length === 0) {
+    return this.$__.activePaths.some('modify');
+  }
+  if (paths.length === 1) {
+    return this.$__.activePaths.states.modify.hasOwnProperty(paths[0]);
+  }
+
+  return paths.some(path => this.$__.activePaths.states.modify.hasOwnProperty(path));
 };
 
 /**
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 1e5336df3fa..060d0125c14 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -200,8 +200,10 @@ describe('document modified', function() {
         post.get('comments')[0].body = 'Woot';
         assert.equal(post.isModified('comments'), true);
         assert.equal(post.isDirectModified('comments'), false);
+        assert.equal(post.isDirectModified(['comments']), false);
         assert.equal(post.isModified('comments.0.body'), true);
         assert.equal(post.isDirectModified('comments.0.body'), true);
+        assert.equal(post.isDirectModified(['comments.0.body', 'comments']), true);
       });
     });
 

From 4780cc33a9b68e5795282294449d1fbdc3a0dad7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Nov 2020 21:23:58 -0500
Subject: [PATCH 1320/2348] feat(document): support space-delimited and array
 for `$isDefault()` and `isInit()`

Re: #9474
---
 lib/document.js                | 36 ++++++++++++++++++++++++++++++++--
 test/document.modified.test.js |  6 +++++-
 test/document.populate.test.js |  1 +
 test/model.populate.test.js    |  3 +++
 4 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 8b071b3d67e..c158d4c2b38 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1933,7 +1933,23 @@ Document.prototype[documentIsModified] = Document.prototype.isModified;
  */
 
 Document.prototype.$isDefault = function(path) {
-  return (path in this.$__.activePaths.states.default);
+  if (path == null) {
+    return this.$__.activePaths.some('default');
+  }
+
+  let paths = path;
+  if (!Array.isArray(paths)) {
+    paths = paths.split(' ');
+  }
+
+  if (paths.length === 0) {
+    return this.$__.activePaths.some('default');
+  }
+  if (paths.length === 1) {
+    return this.$__.activePaths.states.default.hasOwnProperty(paths[0]);
+  }
+
+  return paths.some(path => this.$__.activePaths.states.default.hasOwnProperty(path));
 };
 
 /**
@@ -2009,7 +2025,23 @@ Document.prototype.isDirectModified = function(path) {
  */
 
 Document.prototype.isInit = function(path) {
-  return (path in this.$__.activePaths.states.init);
+  if (path == null) {
+    return this.$__.activePaths.some('init');
+  }
+
+  let paths = path;
+  if (!Array.isArray(paths)) {
+    paths = paths.split(' ');
+  }
+
+  if (paths.length === 0) {
+    return this.$__.activePaths.some('init');
+  }
+  if (paths.length === 1) {
+    return this.$__.activePaths.states.init.hasOwnProperty(paths[0]);
+  }
+
+  return paths.some(path => this.$__.activePaths.states.init.hasOwnProperty(path));
 };
 
 /**
diff --git a/test/document.modified.test.js b/test/document.modified.test.js
index 060d0125c14..a9fe4d61eaf 100644
--- a/test/document.modified.test.js
+++ b/test/document.modified.test.js
@@ -125,9 +125,13 @@ describe('document modified', function() {
   describe('isDefault', function() {
     it('works', function() {
       const MyModel = db.model('Test',
-        { name: { type: String, default: 'Val ' } });
+        { name: { type: String, default: 'Val ' }, other: String });
       const m = new MyModel();
       assert.ok(m.$isDefault('name'));
+      assert.ok(!m.$isDefault('other'));
+
+      assert.ok(m.$isDefault(['name', 'other']));
+      assert.ok(!m.$isDefault(['other']));
     });
   });
 
diff --git a/test/document.populate.test.js b/test/document.populate.test.js
index 4e7c7e3930b..79b9abaae19 100644
--- a/test/document.populate.test.js
+++ b/test/document.populate.test.js
@@ -256,6 +256,7 @@ describe('document.populate', function() {
         assert.ok(!post.fans[0].email);
         assert.ok(!post.fans[1].email);
         assert.ok(!post.fans[0].isInit('email'));
+        assert.ok(!post.fans[0].isInit(['email']));
         assert.ok(!post.fans[1].isInit('email'));
         done();
       });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index cae7093e49a..59cc8c78261 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -1054,8 +1054,11 @@ describe('model: populate:', function() {
                   assert.equal(blogposts[0].fans[0].name, 'Fan 3');
                   assert.equal(blogposts[0].fans[0].email, 'fan3@learnboost.com');
                   assert.equal(blogposts[0].fans[0].isInit('email'), true);
+                  assert.equal(blogposts[0].fans[0].isInit(['email']), true);
                   assert.equal(blogposts[0].fans[0].isInit('gender'), false);
                   assert.equal(blogposts[0].fans[0].isInit('age'), false);
+                  assert.equal(blogposts[0].fans[0].isInit(['email', 'age']), true);
+                  assert.equal(blogposts[0].fans[0].isInit(['gender', 'age']), false);
 
                   assert.strictEqual(blogposts[1].fans.length, 1);
                   assert.equal(blogposts[1].fans[0].name, 'Fan 3');

From 9427bcf54848ceca2124618949fa01d614f70196 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 6 Nov 2020 16:32:21 +0200
Subject: [PATCH 1321/2348] Upgrade mongodb driver to 3.6.3

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 58f8e4b138d..e23e38ac41e 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "bson": "^1.1.4",
     "kareem": "2.3.1",
-    "mongodb": "3.6.2",
+    "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.7.0",
     "mquery": "3.2.2",

From 3ac1236219155cfb6d729d8bb8e888c1e69d107d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 10:38:29 -0500
Subject: [PATCH 1322/2348] test: clean up some flakey geojson tests

---
 test/geojson.test.js | 3 +++
 test/model.test.js   | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/test/geojson.test.js b/test/geojson.test.js
index f99e3f72f23..a75d561ae95 100644
--- a/test/geojson.test.js
+++ b/test/geojson.test.js
@@ -132,6 +132,9 @@ describe('geojson', function() {
     const $geometry = { type: 'Point', coordinates: [-104.8719443, 38.8783536] };
 
     return City.create({ name: 'Denver', location: denver }).
+      // acquit:ignore:start
+      then(() => City.init()).
+      // acquit:ignore:end
       // Without a 2dsphere index, this will error out with:
       // 'unable to find index for $geoNear query"
       then(() => City.findOne({ location: { $near: { $geometry } } })).
diff --git a/test/model.test.js b/test/model.test.js
index 34b3a4e484d..8a54e946d65 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4077,7 +4077,8 @@ describe('Model', function() {
       const Location = db.model('Test', LocationSchema);
 
       return co(function*() {
-        yield Location.collection.drop();
+        yield Location.collection.drop().catch(() => {});
+        yield Location.createCollection();
         yield Location.createIndexes();
 
         yield Location.create({

From 8b0e8694c9bd33f738ee0c6b4b0fd876704fec14 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 10:47:21 -0500
Subject: [PATCH 1323/2348] chore: release 5.10.13

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 3d10eb7e52c..e5212708f83 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.10.13 / 2020-11-06
+====================
+ * fix: upgrade mongodb driver -> 3.6.3 for Lambda cold start fixes #9521 #9179 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(document): correctly handle setting props to other nested props #9519
+
 5.10.12 / 2020-11-04
 ====================
  * fix(connection): catch and report sync errors in connection wrappers like `startSession()` #9515
diff --git a/package.json b/package.json
index e23e38ac41e..c4576415952 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.12",
+  "version": "5.10.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 09da50aa75724d38201c84b99a8835bafdffc191 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 11:17:44 -0500
Subject: [PATCH 1324/2348] refactor(document): support arrays and
 space-delimited for `$isDefault()`, `isInit()`, `isDirectModified()` with one
 fewer `if`

Re: #9474
---
 lib/document.js | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index c158d4c2b38..7cf1e0f5696 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1937,18 +1937,15 @@ Document.prototype.$isDefault = function(path) {
     return this.$__.activePaths.some('default');
   }
 
+  if (typeof path === 'string' && path.indexOf(' ') === -1) {
+    return this.$__.activePaths.states.default.hasOwnProperty(path);
+  }
+
   let paths = path;
   if (!Array.isArray(paths)) {
     paths = paths.split(' ');
   }
 
-  if (paths.length === 0) {
-    return this.$__.activePaths.some('default');
-  }
-  if (paths.length === 1) {
-    return this.$__.activePaths.states.default.hasOwnProperty(paths[0]);
-  }
-
   return paths.some(path => this.$__.activePaths.states.default.hasOwnProperty(path));
 };
 
@@ -2001,18 +1998,15 @@ Document.prototype.isDirectModified = function(path) {
     return this.$__.activePaths.some('modify');
   }
 
+  if (typeof path === 'string' && path.indexOf(' ') === -1) {
+    return this.$__.activePaths.states.modify.hasOwnProperty(path);
+  }
+
   let paths = path;
   if (!Array.isArray(paths)) {
     paths = paths.split(' ');
   }
 
-  if (paths.length === 0) {
-    return this.$__.activePaths.some('modify');
-  }
-  if (paths.length === 1) {
-    return this.$__.activePaths.states.modify.hasOwnProperty(paths[0]);
-  }
-
   return paths.some(path => this.$__.activePaths.states.modify.hasOwnProperty(path));
 };
 
@@ -2029,18 +2023,15 @@ Document.prototype.isInit = function(path) {
     return this.$__.activePaths.some('init');
   }
 
+  if (typeof path === 'string' && path.indexOf(' ') === -1) {
+    return this.$__.activePaths.states.init.hasOwnProperty(path);
+  }
+
   let paths = path;
   if (!Array.isArray(paths)) {
     paths = paths.split(' ');
   }
 
-  if (paths.length === 0) {
-    return this.$__.activePaths.some('init');
-  }
-  if (paths.length === 1) {
-    return this.$__.activePaths.states.init.hasOwnProperty(paths[0]);
-  }
-
   return paths.some(path => this.$__.activePaths.states.init.hasOwnProperty(path));
 };
 

From 51ca0d16fb866e2a7f8adbc9cd5d6dc42133ff97 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 11:31:40 -0500
Subject: [PATCH 1325/2348] feat(document): support array and space-delimited
 syntax for `Document#isSelected()`

Re: #9474
---
 lib/document.js                  | 90 ++++++++++++++++----------------
 test/document.isselected.test.js |  8 +++
 2 files changed, 54 insertions(+), 44 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 7cf1e0f5696..d57f96a0dc0 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2045,69 +2045,71 @@ Document.prototype.isInit = function(path) {
  *        doc.isSelected('age')  // false
  *     })
  *
- * @param {String} path
+ * @param {String|Array<String>} path
  * @return {Boolean}
  * @api public
  */
 
 Document.prototype.isSelected = function isSelected(path) {
-  if (this.$__.selected) {
-    if (path === '_id') {
-      return this.$__.selected._id !== 0;
-    }
+  if (this.$__.selected == null) {
+    return true;
+  }
 
-    const paths = Object.keys(this.$__.selected);
-    let i = paths.length;
-    let inclusive = null;
-    let cur;
+  if (path === '_id') {
+    return this.$__.selected._id !== 0;
+  }
 
-    if (i === 1 && paths[0] === '_id') {
-      // only _id was selected.
-      return this.$__.selected._id === 0;
-    }
+  if (path.indexOf(' ') !== -1) {
+    path = path.split(' ');
+  }
+  if (Array.isArray(path)) {
+    return path.some(p => this.isSelected(p));
+  }
 
-    while (i--) {
-      cur = paths[i];
-      if (cur === '_id') {
-        continue;
-      }
-      if (!isDefiningProjection(this.$__.selected[cur])) {
-        continue;
-      }
-      inclusive = !!this.$__.selected[cur];
-      break;
-    }
+  const paths = Object.keys(this.$__.selected);
+  let inclusive = null;
 
-    if (inclusive === null) {
-      return true;
-    }
+  if (paths.length === 1 && paths[0] === '_id') {
+    // only _id was selected.
+    return this.$__.selected._id === 0;
+  }
 
-    if (path in this.$__.selected) {
-      return inclusive;
+  for (const cur of paths) {
+    if (cur === '_id') {
+      continue;
+    }
+    if (!isDefiningProjection(this.$__.selected[cur])) {
+      continue;
     }
+    inclusive = !!this.$__.selected[cur];
+    break;
+  }
 
-    i = paths.length;
-    const pathDot = path + '.';
+  if (inclusive === null) {
+    return true;
+  }
 
-    while (i--) {
-      cur = paths[i];
-      if (cur === '_id') {
-        continue;
-      }
+  if (path in this.$__.selected) {
+    return inclusive;
+  }
 
-      if (cur.startsWith(pathDot)) {
-        return inclusive || cur !== pathDot;
-      }
+  const pathDot = path + '.';
 
-      if (pathDot.startsWith(cur + '.')) {
-        return inclusive;
-      }
+  for (const cur of paths) {
+    if (cur === '_id') {
+      continue;
     }
 
-    return !inclusive;
+    if (cur.startsWith(pathDot)) {
+      return inclusive || cur !== pathDot;
+    }
+
+    if (pathDot.startsWith(cur + '.')) {
+      return inclusive;
+    }
   }
 
-  return true;
+  return !inclusive;
 };
 
 Document.prototype[documentIsSelected] = Document.prototype.isSelected;
diff --git a/test/document.isselected.test.js b/test/document.isselected.test.js
index 70d4abb9277..b154006bc1f 100644
--- a/test/document.isselected.test.js
+++ b/test/document.isselected.test.js
@@ -170,6 +170,14 @@ describe('document', function() {
     assert.ok(!doc.isSelected('em.body'));
     assert.ok(!doc.isSelected('em.nonpath'));
 
+    assert.ok(doc.isSelected('_id test'));
+    assert.ok(doc.isSelected('test nested.nope'));
+    assert.ok(!doc.isSelected('nested.path nested.nope'));
+
+    assert.ok(doc.isSelected(['_id', 'test']));
+    assert.ok(doc.isSelected(['test', 'nested.nope']));
+    assert.ok(!doc.isSelected(['nested.path', 'nested.nope']));
+
     selection = {
       'em.title': 1
     };

From 5b79a9e79730bf263cd09254cbe33e4e8ff6cb0f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 11:47:11 -0500
Subject: [PATCH 1326/2348] feat(document): support space-delimited and array
 syntax for `Document#isDirectSelected()` re: #9474

---
 lib/document.js                  | 64 +++++++++++++++++---------------
 test/document.isselected.test.js |  6 +++
 2 files changed, 40 insertions(+), 30 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d57f96a0dc0..d432c678b53 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2132,45 +2132,49 @@ Document.prototype[documentIsSelected] = Document.prototype.isSelected;
  */
 
 Document.prototype.isDirectSelected = function isDirectSelected(path) {
-  if (this.$__.selected) {
-    if (path === '_id') {
-      return this.$__.selected._id !== 0;
-    }
+  if (this.$__.selected == null) {
+    return true;
+  }
 
-    const paths = Object.keys(this.$__.selected);
-    let i = paths.length;
-    let inclusive = null;
-    let cur;
+  if (path === '_id') {
+    return this.$__.selected._id !== 0;
+  }
 
-    if (i === 1 && paths[0] === '_id') {
-      // only _id was selected.
-      return this.$__.selected._id === 0;
-    }
+  if (path.indexOf(' ') !== -1) {
+    path = path.split(' ');
+  }
+  if (Array.isArray(path)) {
+    return path.some(p => this.isDirectSelected(p));
+  }
 
-    while (i--) {
-      cur = paths[i];
-      if (cur === '_id') {
-        continue;
-      }
-      if (!isDefiningProjection(this.$__.selected[cur])) {
-        continue;
-      }
-      inclusive = !!this.$__.selected[cur];
-      break;
-    }
+  const paths = Object.keys(this.$__.selected);
+  let inclusive = null;
 
-    if (inclusive === null) {
-      return true;
-    }
+  if (paths.length === 1 && paths[0] === '_id') {
+    // only _id was selected.
+    return this.$__.selected._id === 0;
+  }
 
-    if (path in this.$__.selected) {
-      return inclusive;
+  for (const cur of paths) {
+    if (cur === '_id') {
+      continue;
+    }
+    if (!isDefiningProjection(this.$__.selected[cur])) {
+      continue;
     }
+    inclusive = !!this.$__.selected[cur];
+    break;
+  }
 
-    return !inclusive;
+  if (inclusive === null) {
+    return true;
   }
 
-  return true;
+  if (this.$__.selected.hasOwnProperty(path)) {
+    return inclusive;
+  }
+
+  return !inclusive;
 };
 
 /**
diff --git a/test/document.isselected.test.js b/test/document.isselected.test.js
index b154006bc1f..d013eed5efb 100644
--- a/test/document.isselected.test.js
+++ b/test/document.isselected.test.js
@@ -363,5 +363,11 @@ describe('document', function() {
     assert.ok(doc.isDirectSelected('nested.deep'));
     assert.ok(!doc.isDirectSelected('nested.cool'));
     assert.ok(!doc.isDirectSelected('nested'));
+
+    assert.ok(doc.isDirectSelected('nested.deep nested'));
+    assert.ok(!doc.isDirectSelected('nested.cool nested'));
+
+    assert.ok(doc.isDirectSelected(['nested.deep', 'nested']));
+    assert.ok(!doc.isDirectSelected(['nested.cool', 'nested']));
   });
 });

From c0bdf6fe6ac2389956cbe8b0221e2041ae38ae36 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 11:57:14 -0500
Subject: [PATCH 1327/2348] feat(document): support array and space-delimited
 syntax for `Document#$isValid()`

Fix #9474
---
 lib/document.js       | 18 ++++++++++++++++--
 test/document.test.js | 24 ++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d432c678b53..6504b8ae6d0 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2819,7 +2819,7 @@ function _checkImmutableSubpaths(subdoc, schematype, priorVal) {
 /**
  * Checks if a path is invalid
  *
- * @param {String} path the field to check
+ * @param {String|Array<String>} path the field to check
  * @method $isValid
  * @memberOf Document
  * @instance
@@ -2827,7 +2827,21 @@ function _checkImmutableSubpaths(subdoc, schematype, priorVal) {
  */
 
 Document.prototype.$isValid = function(path) {
-  return !this.$__.validationError || !this.$__.validationError.errors[path];
+  if (this.$__.validationError == null || Object.keys(this.$__.validationError.errors).length === 0) {
+    return true;
+  }
+  if (path == null) {
+    return false;
+  }
+
+  if (path.indexOf(' ') !== -1) {
+    path = path.split(' ');
+  }
+  if (Array.isArray(path)) {
+    return path.some(p => this.$__.validationError.errors[p] == null);
+  }
+
+  return this.$__.validationError.errors[path] == null;
 };
 
 /**
diff --git a/test/document.test.js b/test/document.test.js
index cf04b73bcdb..1a24ff9158d 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9549,6 +9549,30 @@ describe('document', function() {
     assert.deepEqual(testUser.toObject().preferences.notifications, { email: true, push: false });
   });
 
+  it('$isValid() with space-delimited and array syntax (gh-9474)', function() {
+    const Test = db.model('Test', Schema({
+      name: String,
+      email: String,
+      age: Number,
+      answer: Number
+    }));
+
+    const doc = new Test({ name: 'test', email: 'test@gmail.com', age: 'bad', answer: 'bad' });
+
+    assert.ok(doc.$isValid('name'));
+    assert.ok(doc.$isValid('email'));
+    assert.ok(!doc.$isValid('age'));
+    assert.ok(!doc.$isValid('answer'));
+
+    assert.ok(doc.$isValid('name email'));
+    assert.ok(doc.$isValid('name age'));
+    assert.ok(!doc.$isValid('age answer'));
+
+    assert.ok(doc.$isValid(['name', 'email']));
+    assert.ok(doc.$isValid(['name', 'age']));
+    assert.ok(!doc.$isValid(['age', 'answer']));
+  });
+
   it('avoids overwriting array subdocument when setting dotted path that is not selected (gh-9427)', function() {
     const Test = db.model('Test', Schema({
       arr: [{ _id: false, val: Number }],

From c1d2bf1c6edecfb8f35557b9df65cb3fb4b79bad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 17:29:03 -0500
Subject: [PATCH 1328/2348] feat(connection+mongoose): allow setting
 `overwriteModels` option to `model()` to avoid throwing `OverwriteModelError`

Re: #9406
---
 lib/connection.js       |  8 +++++---
 lib/index.js            |  4 ++--
 test/connection.test.js | 12 ++++++++++++
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index bf4fce8f627..6580c94eff3 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1141,12 +1141,14 @@ Connection.prototype.plugin = function(fn, opts) {
  * @param {String|Function} name the model name or class extending Model
  * @param {Schema} [schema] a schema. necessary when defining a model
  * @param {String} [collection] name of mongodb collection (optional) if not given it will be induced from model name
+ * @param {Object} [options]
+ * @param {Boolean} [options.overwriteModels=false] If true, overwrite existing models with the same name to avoid `OverwriteModelError`
  * @see Mongoose#model #index_Mongoose-model
  * @return {Model} The compiled model
  * @api public
  */
 
-Connection.prototype.model = function(name, schema, collection) {
+Connection.prototype.model = function(name, schema, collection, options) {
   if (!(this instanceof Connection)) {
     throw new MongooseError('`connection.model()` should not be run with ' +
       '`new`. If you are doing `new db.model(foo)(bar)`, use ' +
@@ -1173,7 +1175,8 @@ Connection.prototype.model = function(name, schema, collection) {
       'schema or a POJO');
   }
 
-  if (this.models[name] && !collection) {
+  const opts = Object.assign({ cache: false }, options, { connection: this });
+  if (this.models[name] && !collection && opts.overwriteModels !== true) {
     // model exists but we are not subclassing with custom collection
     if (schema && schema.instanceOfSchema && schema !== this.models[name].schema) {
       throw new MongooseError.OverwriteModelError(name);
@@ -1181,7 +1184,6 @@ Connection.prototype.model = function(name, schema, collection) {
     return this.models[name];
   }
 
-  const opts = { cache: false, connection: this };
   let model;
 
   if (schema && schema.instanceOfSchema) {
diff --git a/lib/index.js b/lib/index.js
index 5769cc59970..f1fd9c7a7fe 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -465,7 +465,7 @@ Mongoose.prototype.pluralize = function(fn) {
  * @param {String|Function} name model name or class extending Model
  * @param {Schema} [schema] the schema to use.
  * @param {String} [collection] name (optional, inferred from model name)
- * @param {Boolean} [skipInit] whether to skip initialization (defaults to false)
+ * @param {Boolean|Object} [skipInit] whether to skip initialization (defaults to false). If an object, treated as options.
  * @return {Model} The model associated with `name`. Mongoose will create the model if it doesn't already exist.
  * @api public
  */
@@ -531,7 +531,7 @@ Mongoose.prototype.model = function(name, schema, collection, skipInit) {
 
   // connection.model() may be passing a different schema for
   // an existing model name. in this case don't read from cache.
-  if (_mongoose.models[name] && options.cache !== false) {
+  if (_mongoose.models[name] && options.cache !== false && options.overwriteModels !== true) {
     if (originalSchema &&
         originalSchema.instanceOfSchema &&
         originalSchema !== _mongoose.models[name].schema) {
diff --git a/test/connection.test.js b/test/connection.test.js
index 15049eb0a95..dbff8d4aa33 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1239,4 +1239,16 @@ describe('connections:', function() {
     });
   });
 
+  it('allows overwriting models (gh-9406)', function() {
+    const m = new mongoose.Mongoose();
+
+    const M1 = m.model('Test', Schema({ name: String }), null, { overwriteModels: true });
+    const M2 = m.model('Test', Schema({ name: String }), null, { overwriteModels: true });
+    const M3 = m.connection.model('Test', Schema({ name: String }), null, { overwriteModels: true });
+
+    assert.ok(M1 !== M2);
+    assert.ok(M2 !== M3);
+
+    assert.throws(() => m.model('Test', Schema({ name: String })), /overwrite/);
+  });
 });

From df86f53b631ae84ace1d19d871a4b756a362599b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 17:39:05 -0500
Subject: [PATCH 1329/2348] feat(connection+index): add support for global
 `overwriteModels` option

Fix #9406
---
 lib/connection.js       |  3 ++-
 lib/index.js            |  6 +++++-
 lib/validoptions.js     |  1 +
 test/connection.test.js | 15 +++++++++++++++
 4 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 6580c94eff3..d635b765d8b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1175,7 +1175,8 @@ Connection.prototype.model = function(name, schema, collection, options) {
       'schema or a POJO');
   }
 
-  const opts = Object.assign({ cache: false }, options, { connection: this });
+  const defaultOptions = { cache: false, overwriteModels: this.base.options.overwriteModels };
+  const opts = Object.assign(defaultOptions, options, { connection: this });
   if (this.models[name] && !collection && opts.overwriteModels !== true) {
     // model exists but we are not subclassing with custom collection
     if (schema && schema.instanceOfSchema && schema !== this.models[name].schema) {
diff --git a/lib/index.js b/lib/index.js
index f1fd9c7a7fe..96bc8098832 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -167,6 +167,7 @@ Mongoose.prototype.driver = require('./driver');
  * - 'maxTimeMS': If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query
  * - 'autoIndex': true by default. Set to false to disable automatic index creation for all models associated with this Mongoose instance.
  * - 'autoCreate': Set to `true` to make Mongoose call [`Model.createCollection()`](/docs/api/model.html#model_Model.createCollection) automatically when you create a model with `mongoose.model()` or `conn.model()`. This is useful for testing transactions, change streams, and other features that require the collection to exist.
+ * - 'overwriteModels': Set to `true` to default to overwriting models with the same name when calling `mongoose.model()`, as opposed to throwing an `OverwriteModelError`.
  *
  * @param {String} key
  * @param {String|Function|Boolean} value
@@ -531,7 +532,10 @@ Mongoose.prototype.model = function(name, schema, collection, skipInit) {
 
   // connection.model() may be passing a different schema for
   // an existing model name. in this case don't read from cache.
-  if (_mongoose.models[name] && options.cache !== false && options.overwriteModels !== true) {
+  const overwriteModels = this.options.hasOwnProperty('overwriteModels') ?
+    this.options.overwriteModels :
+    options.overwriteModels;
+  if (_mongoose.models[name] && options.cache !== false && overwriteModels !== true) {
     if (originalSchema &&
         originalSchema.instanceOfSchema &&
         originalSchema !== _mongoose.models[name].schema) {
diff --git a/lib/validoptions.js b/lib/validoptions.js
index 3eb19550e6f..fb47f316a8f 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -16,6 +16,7 @@ const VALID_OPTIONS = Object.freeze([
   'debug',
   'maxTimeMS',
   'objectIdGetter',
+  'overwriteModels',
   'returnOriginal',
   'runValidators',
   'selectPopulatedPaths',
diff --git a/test/connection.test.js b/test/connection.test.js
index dbff8d4aa33..233bec28c4b 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1251,4 +1251,19 @@ describe('connections:', function() {
 
     assert.throws(() => m.model('Test', Schema({ name: String })), /overwrite/);
   });
+
+  it('allows setting `overwriteModels` globally (gh-9406)', function() {
+    const m = new mongoose.Mongoose();
+    m.set('overwriteModels', true);
+
+    const M1 = m.model('Test', Schema({ name: String }));
+    const M2 = m.model('Test', Schema({ name: String }));
+    const M3 = m.connection.model('Test', Schema({ name: String }));
+
+    assert.ok(M1 !== M2);
+    assert.ok(M2 !== M3);
+
+    m.set('overwriteModels', false);
+    assert.throws(() => m.model('Test', Schema({ name: String })), /overwrite/);
+  });
 });

From ad1d18a8c5f806d526c5441f8ad2f06ccbd62c20 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 22:07:17 -0500
Subject: [PATCH 1330/2348] feat: support getters on populate virtuals,
 including `get` option for `Schema#virtual()`

Fix #9343
---
 lib/schema.js               | 65 +++++++++++++++++++++----------------
 test/model.populate.test.js | 57 ++++++++++++++++++++++++++++++++
 2 files changed, 94 insertions(+), 28 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 2abd0a01a28..5e27037fb98 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1674,6 +1674,7 @@ Schema.prototype.indexes = function() {
  * @param {String|Function} [options.foreignField] Required for populate virtuals. See [populate virtual docs](populate.html#populate-virtuals) for more information.
  * @param {Boolean|Function} [options.justOne=false] Only works with populate virtuals. If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), will be a single doc or `null`. Otherwise, the populate virtual will be an array.
  * @param {Boolean} [options.count=false] Only works with populate virtuals. If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), this populate virtual will contain the number of documents rather than the documents themselves when you `populate()`.
+ * @param {Function|null} [options.get=null] Adds a [getter](/docs/tutorials/getters-setters.html) to this virtual to transform the populated doc.
  * @return {VirtualType}
  */
 
@@ -1716,38 +1717,46 @@ Schema.prototype.virtual = function(name, options) {
 
     const virtual = this.virtual(name);
     virtual.options = options;
-    return virtual.
-      get(function(_v) {
-        if (this.$$populatedVirtuals &&
-          this.$$populatedVirtuals.hasOwnProperty(name)) {
-          return this.$$populatedVirtuals[name];
-        }
-        if (_v == null) return undefined;
-        return _v;
-      }).
-      set(function(_v) {
-        if (!this.$$populatedVirtuals) {
-          this.$$populatedVirtuals = {};
-        }
+    process.nextTick(() => {
+      virtual.
+        get(function(_v) {
+          if (this.$$populatedVirtuals &&
+            this.$$populatedVirtuals.hasOwnProperty(name)) {
+            return this.$$populatedVirtuals[name];
+          }
+          if (_v == null) return undefined;
+          return _v;
+        }).
+        set(function(_v) {
+          if (!this.$$populatedVirtuals) {
+            this.$$populatedVirtuals = {};
+          }
 
-        if (options.justOne || options.count) {
-          this.$$populatedVirtuals[name] = Array.isArray(_v) ?
-            _v[0] :
-            _v;
+          if (options.justOne || options.count) {
+            this.$$populatedVirtuals[name] = Array.isArray(_v) ?
+              _v[0] :
+              _v;
 
-          if (typeof this.$$populatedVirtuals[name] !== 'object') {
-            this.$$populatedVirtuals[name] = options.count ? _v : null;
+            if (typeof this.$$populatedVirtuals[name] !== 'object') {
+              this.$$populatedVirtuals[name] = options.count ? _v : null;
+            }
+          } else {
+            this.$$populatedVirtuals[name] = Array.isArray(_v) ?
+              _v :
+              _v == null ? [] : [_v];
+
+            this.$$populatedVirtuals[name] = this.$$populatedVirtuals[name].filter(function(doc) {
+              return doc && typeof doc === 'object';
+            });
           }
-        } else {
-          this.$$populatedVirtuals[name] = Array.isArray(_v) ?
-            _v :
-            _v == null ? [] : [_v];
+        });
+    });
 
-          this.$$populatedVirtuals[name] = this.$$populatedVirtuals[name].filter(function(doc) {
-            return doc && typeof doc === 'object';
-          });
-        }
-      });
+    if (typeof options.get === 'function') {
+      virtual.get(options.get);
+    }
+
+    return virtual;
   }
 
   const virtuals = this.virtuals;
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 59cc8c78261..f8e56ca2ed5 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -4708,6 +4708,63 @@ describe('model: populate:', function() {
         });
       });
 
+      it('virtuals with getters (gh-9343)', function() {
+        const UserSchema = new Schema({
+          openId: String,
+          test: String
+        });
+        const CommentSchema = new Schema({
+          openId: String
+        });
+
+        CommentSchema.virtual('user', {
+          ref: 'User',
+          localField: 'openId',
+          foreignField: 'openId',
+          justOne: true
+        }).get(v => v.test);
+
+        const User = db.model('User', UserSchema);
+        const Comment = db.model('Comment', CommentSchema);
+
+        return co(function*() {
+          yield Comment.create({ openId: 'test' });
+          yield User.create({ openId: 'test', test: 'my string' });
+
+          const comment = yield Comment.findOne({ openId: 'test' }).populate('user');
+          assert.equal(comment.user, 'my string');
+        });
+      });
+
+      it('virtuals with `get` option (gh-9343)', function() {
+        const UserSchema = new Schema({
+          openId: String,
+          test: String
+        });
+        const CommentSchema = new Schema({
+          openId: String
+        });
+
+        CommentSchema.virtual('user', {
+          ref: 'User',
+          localField: 'openId',
+          foreignField: 'openId',
+          justOne: true,
+          get: v => v.test
+        });
+
+        const User = db.model('User', UserSchema);
+        const Comment = db.model('Comment', CommentSchema);
+
+        return co(function*() {
+          yield Comment.create({ openId: 'test' });
+          yield User.create({ openId: 'test', test: 'my string' });
+
+          const comment = yield Comment.findOne({ openId: 'test' }).populate('user');
+          assert.equal(comment.user, 'my string');
+        });
+      });
+
       it('hydrates properly (gh-4618)', function(done) {
         const ASchema = new Schema({
           name: { type: String }

From abb2e74adacd980021e6fb337fb7c57da220db2b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 6 Nov 2020 22:12:17 -0500
Subject: [PATCH 1331/2348] test: fix test re: #9406

---
 lib/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 96bc8098832..bce1be25629 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -532,8 +532,8 @@ Mongoose.prototype.model = function(name, schema, collection, skipInit) {
 
   // connection.model() may be passing a different schema for
   // an existing model name. in this case don't read from cache.
-  const overwriteModels = this.options.hasOwnProperty('overwriteModels') ?
-    this.options.overwriteModels :
+  const overwriteModels = _mongoose.options.hasOwnProperty('overwriteModels') ?
+    _mongoose.options.overwriteModels :
     options.overwriteModels;
   if (_mongoose.models[name] && options.cache !== false && overwriteModels !== true) {
     if (originalSchema &&

From e0c7006229cc38dd7842433ad5087b20dda46cc7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 7 Nov 2020 09:53:24 -0500
Subject: [PATCH 1332/2348] fix(virtualtype): always get populated virtual
 value before running getters, better fix for #9343

---
 lib/schema.js      | 53 +++++++++++++++++++---------------------------
 lib/virtualtype.js |  8 +++++++
 2 files changed, 30 insertions(+), 31 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 5e27037fb98..7986f9f35f4 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1717,40 +1717,31 @@ Schema.prototype.virtual = function(name, options) {
 
     const virtual = this.virtual(name);
     virtual.options = options;
-    process.nextTick(() => {
-      virtual.
-        get(function(_v) {
-          if (this.$$populatedVirtuals &&
-            this.$$populatedVirtuals.hasOwnProperty(name)) {
-            return this.$$populatedVirtuals[name];
-          }
-          if (_v == null) return undefined;
-          return _v;
-        }).
-        set(function(_v) {
-          if (!this.$$populatedVirtuals) {
-            this.$$populatedVirtuals = {};
-          }
 
-          if (options.justOne || options.count) {
-            this.$$populatedVirtuals[name] = Array.isArray(_v) ?
-              _v[0] :
-              _v;
+    virtual.
+      set(function(_v) {
+        if (!this.$$populatedVirtuals) {
+          this.$$populatedVirtuals = {};
+        }
 
-            if (typeof this.$$populatedVirtuals[name] !== 'object') {
-              this.$$populatedVirtuals[name] = options.count ? _v : null;
-            }
-          } else {
-            this.$$populatedVirtuals[name] = Array.isArray(_v) ?
-              _v :
-              _v == null ? [] : [_v];
-
-            this.$$populatedVirtuals[name] = this.$$populatedVirtuals[name].filter(function(doc) {
-              return doc && typeof doc === 'object';
-            });
+        if (options.justOne || options.count) {
+          this.$$populatedVirtuals[name] = Array.isArray(_v) ?
+            _v[0] :
+            _v;
+
+          if (typeof this.$$populatedVirtuals[name] !== 'object') {
+            this.$$populatedVirtuals[name] = options.count ? _v : null;
           }
-        });
-    });
+        } else {
+          this.$$populatedVirtuals[name] = Array.isArray(_v) ?
+            _v :
+            _v == null ? [] : [_v];
+
+          this.$$populatedVirtuals[name] = this.$$populatedVirtuals[name].filter(function(doc) {
+            return doc && typeof doc === 'object';
+          });
+        }
+      });
 
     if (typeof options.get === 'function') {
       virtual.get(options.get);
diff --git a/lib/virtualtype.js b/lib/virtualtype.js
index 35f26b45e7b..2473aac3fbd 100644
--- a/lib/virtualtype.js
+++ b/lib/virtualtype.js
@@ -1,5 +1,7 @@
 'use strict';
 
+const utils = require('./utils');
+
 /**
  * VirtualType constructor
  *
@@ -137,6 +139,12 @@ VirtualType.prototype.set = function(fn) {
  */
 
 VirtualType.prototype.applyGetters = function(value, doc) {
+  if (utils.hasUserDefinedProperty(this.options, ['ref', 'refPath']) &&
+      doc.$$populatedVirtuals &&
+      doc.$$populatedVirtuals.hasOwnProperty(this.path)) {
+    value = doc.$$populatedVirtuals[this.path];
+  }
+
   let v = value;
   for (let l = this.getters.length - 1; l >= 0; l--) {
     v = this.getters[l].call(doc, v, this, doc);

From 0ffcf3b35a05f28883010dadee4bd7d5925798f1 Mon Sep 17 00:00:00 2001
From: Kevin Sullivan <ksullivan@users.noreply.github.com>
Date: Sat, 7 Nov 2020 21:19:49 +0000
Subject: [PATCH 1333/2348] Remove redundant code.

Query.prototype.mongooseOptions is set to a function and then immediately overwritten with another function. This change removes the first redundant assignment.
---
 lib/query.js | 33 ---------------------------------
 1 file changed, 33 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index d6ce0bf64e5..d270efbf84b 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1687,39 +1687,6 @@ Query.prototype.lean = function(v) {
   return this;
 };
 
-/**
- * Returns an object containing the Mongoose-specific options for this query,
- * including `lean` and `populate`.
- *
- * Mongoose-specific options are different from normal options (`sort`, `limit`, etc.)
- * because they are **not** sent to the MongoDB server.
- *
- * ####Example:
- *
- *     const q = new Query();
- *     q.mongooseOptions().lean; // undefined
- *
- *     q.lean();
- *     q.mongooseOptions().lean; // true
- *
- * This function is useful for writing [query middleware](/docs/middleware.html).
- * Below is a full list of properties the return value from this function may have:
- *
- * - `populate`
- * - `lean`
- * - `omitUndefined`
- * - `strict`
- * - `nearSphere`
- * - `useFindAndModify`
- *
- * @return {Object} Mongoose-specific options
- * @param public
- */
-
-Query.prototype.mongooseOptions = function() {
-  return this._mongooseOptions;
-};
-
 /**
  * Adds a `$set` to this query's update without changing the operation.
  * This is useful for query middleware so you can add an update regardless

From b9553b6b63b22eb27cc1e9e421d0ae3701e3ebe3 Mon Sep 17 00:00:00 2001
From: mustafaKamal-fe <54776055+mustafaKamal-fe@users.noreply.github.com>
Date: Sun, 8 Nov 2020 19:32:04 +0300
Subject: [PATCH 1334/2348] Update middlewar.pug file

the documentation does not specificly addresses that both properties 'query' and 'document' must be assigned in order for the 'remove' middleware to execute for the right context (that is on the query or the document).
---
 docs/middleware.pug | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index 0d09570584d..5e5cf8a3f6f 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -329,17 +329,17 @@ block content
     You can pass options to [`Schema.pre()`](/docs/api.html#schema_Schema-pre)
     and [`Schema.post()`](/docs/api.html#schema_Schema-post) to switch whether
     Mongoose calls your `remove()` hook for [`Document.remove()`](/docs/api.html#model_Model-remove)
-    or [`Model.remove()`](/docs/api.html#model_Model.remove):
+    or [`Model.remove()`](/docs/api.html#model_Model.remove). Note here that you need to set both `document` and `query` properties in the passed object:
 
     ```javascript
     // Only document middleware
-    schema.pre('remove', { document: true }, function() {
+    schema.pre('remove', { document: true, query: false}, function() {
       console.log('Removing doc!');
     });
 
     // Only query middleware. This will get called when you do `Model.remove()`
     // but not `doc.remove()`.
-    schema.pre('remove', { query: true }, function() {
+    schema.pre('remove', { query: true, document: flse }, function() {
       console.log('Removing!');
     });
     ```

From 074bfc6d12fbf0a36402c4e075d7705e302e58b9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Nov 2020 12:28:28 -0500
Subject: [PATCH 1335/2348] docs: correct typo

---
 docs/middleware.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index 5e5cf8a3f6f..47ae51c112c 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -339,7 +339,7 @@ block content
 
     // Only query middleware. This will get called when you do `Model.remove()`
     // but not `doc.remove()`.
-    schema.pre('remove', { query: true, document: flse }, function() {
+    schema.pre('remove', { query: true, document: false }, function() {
       console.log('Removing!');
     });
     ```

From ec8ae00b7b4447783e28e410d99853ac6c5fb23d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Nov 2020 12:28:50 -0500
Subject: [PATCH 1336/2348] chore: fix docs typo

---
 docs/middleware.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index 47ae51c112c..a3937b29cf1 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -333,7 +333,7 @@ block content
 
     ```javascript
     // Only document middleware
-    schema.pre('remove', { document: true, query: false}, function() {
+    schema.pre('remove', { document: true, query: false }, function() {
       console.log('Removing doc!');
     });
 

From 96fe1e58e1d3a262a9fd9fc186c1611d926be1b8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Nov 2020 15:33:29 -0500
Subject: [PATCH 1337/2348] fix(document): make fix for #6223 behave with #9343

Came up while working on #6608
---
 lib/document.js | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 6504b8ae6d0..6c90d376013 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1596,10 +1596,7 @@ Document.prototype.get = function(path, type, options) {
   let obj = this._doc;
 
   if (schema instanceof VirtualType) {
-    if (schema.getters.length === 0) {
-      return void 0;
-    }
-    return schema.applyGetters(null, this);
+    return schema.applyGetters(void 0, this);
   }
 
   // Might need to change path for top-level alias

From f8fe68bc70e0987f07c539b8e1332b1e71a8f59b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 8 Nov 2020 20:04:37 -0500
Subject: [PATCH 1338/2348] feat(populate): support populate virtuals with
 `localField` and `foreignField` as arrays

Fix #6608
---
 .../populate/getModelsMapForPopulate.js       | 33 ++++++++++++------
 test/model.populate.test.js                   | 34 ++++++++++++++++---
 2 files changed, 52 insertions(+), 15 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 66baf19fa21..baa76d8f190 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -123,6 +123,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         _virtualRes.nestedSchemaPath + '.' : '';
       if (typeof virtual.options.localField === 'function') {
         localField = virtualPrefix + virtual.options.localField.call(doc, doc);
+      } else if (Array.isArray(virtual.options.localField)) {
+        localField = virtual.options.localField.map(field => virtualPrefix + field);
       } else {
         localField = virtualPrefix + virtual.options.localField;
       }
@@ -193,6 +195,27 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       foreignField = foreignField.call(doc);
     }
 
+    let match = get(options, 'match', null) ||
+      get(currentOptions, 'match', null) ||
+      get(options, 'virtual.options.match', null) ||
+      get(options, 'virtual.options.options.match', null);
+
+    let hasMatchFunction = typeof match === 'function';
+    if (hasMatchFunction) {
+      match = match.call(doc, doc);
+    }
+
+    if (Array.isArray(localField) && Array.isArray(foreignField) && localField.length === foreignField.length) {
+      match = Object.assign({}, match);
+      for (let i = 1; i < localField.length; ++i) {
+        match[foreignField[i]] = convertTo_id(mpath.get(localField[i], doc, lookupLocalFields), schema);
+        hasMatchFunction = true;
+      }
+
+      localField = localField[0];
+      foreignField = foreignField[0];
+    }
+
     const localFieldPathType = modelSchema._getPathType(localField);
     const localFieldPath = localFieldPathType === 'real' ? modelSchema.path(localField) : localFieldPathType.schema;
     const localFieldGetters = localFieldPath && localFieldPath.getters ? localFieldPath.getters : [];
@@ -220,16 +243,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     const id = String(utils.getValue(foreignField, doc));
     options._docs[id] = Array.isArray(ret) ? ret.slice() : ret;
 
-    let match = get(options, 'match', null) ||
-      get(currentOptions, 'match', null) ||
-      get(options, 'virtual.options.match', null) ||
-      get(options, 'virtual.options.options.match', null);
-
-    const hasMatchFunction = typeof match === 'function';
-    if (hasMatchFunction) {
-      match = match.call(doc, doc);
-    }
-
     // Re: gh-8452. Embedded discriminators may not have `refPath`, so clear
     // out embedded discriminator docs that don't have a `refPath` on the
     // populated path.
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index f8e56ca2ed5..0bc27992ec9 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -8864,7 +8864,7 @@ describe('model: populate:', function() {
       });
     });
 
-    it.skip('virtual populate with multiple `localField` and `foreignField` (gh-6608)', function() {
+    it('virtual populate with multiple `localField` and `foreignField` (gh-6608)', function() {
       const employeeSchema = Schema({
         locationId: String,
         departmentId: String,
@@ -8878,19 +8878,27 @@ describe('model: populate:', function() {
         justOne: true
       });
 
+      employeeSchema.virtual('departments', {
+        ref: 'Test',
+        localField: ['locationId', 'departmentId'],
+        foreignField: ['locationId', 'name'],
+        justOne: false
+      });
+
       const departmentSchema = Schema({
         locationId: String,
         name: String
       });
 
       return co(function*() {
+        db.deleteModel(/Test/);
         const Employee = db.model('Person', employeeSchema);
         const Department = db.model('Test', departmentSchema);
 
         yield Employee.create([
-          { locationId: 'Miami', department: 'Engineering', name: 'Valeri Karpov' },
-          { locationId: 'Miami', department: 'Accounting', name: 'Test 1' },
-          { locationId: 'New York', department: 'Engineering', name: 'Test 2' }
+          { locationId: 'Miami', departmentId: 'Engineering', name: 'Valeri Karpov' },
+          { locationId: 'Miami', departmentId: 'Accounting', name: 'Test 1' },
+          { locationId: 'New York', departmentId: 'Engineering', name: 'Test 2' }
         ]);
 
         const depts = yield Department.create([
@@ -8901,9 +8909,25 @@ describe('model: populate:', function() {
         const dept = depts[0];
 
         const doc = yield Employee.findOne({ name: 'Valeri Karpov' }).
-          populate('department');
+          populate('department departments');
         assert.equal(doc.department._id.toHexString(), dept._id.toHexString());
         assert.equal(doc.department.name, 'Engineering');
+
+        assert.equal(doc.departments.length, 1);
+        assert.equal(doc.departments[0]._id.toHexString(), dept._id.toHexString());
+        assert.equal(doc.departments[0].name, 'Engineering');
+
+        const docs = yield Employee.find().
+          sort({ name: 1 }).
+          populate('department');
+
+        assert.equal(docs.length, 3);
+        assert.equal(docs[0].department.name, 'Accounting');
+        assert.equal(docs[0].department.locationId, 'Miami');
+        assert.equal(docs[1].department.name, 'Engineering');
+        assert.equal(docs[1].department.locationId, 'New York');
+        assert.equal(docs[2].department.name, 'Engineering');
+        assert.equal(docs[2].department.locationId, 'Miami');
       });
     });
   });

From 9f3b30202ff176b014f3e8bba05f1cb37f1453a1 Mon Sep 17 00:00:00 2001
From: Vishal Gauba <vishal.gauba@gmail.com>
Date: Sat, 7 Nov 2020 22:23:53 +0530
Subject: [PATCH 1339/2348] fix: make minLength/maxLength behave same as
 minlength/maxlength

---
 docs/schematypes.pug               |  4 ++--
 lib/options/SchemaStringOptions.js |  8 +++++---
 lib/schema/string.js               |  4 ++++
 test/docs/validation.test.js       |  2 +-
 test/errors.validation.test.js     | 28 ++++++++++++++++++----------
 5 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 2309045890d..5b0b16fdc33 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -288,8 +288,8 @@ block content
     * `trim`: boolean, whether to always call `.trim()` on the value
     * `match`: RegExp, creates a [validator](./validation.html) that checks if the value matches the given regular expression
     * `enum`: Array, creates a [validator](./validation.html) that checks if the value is in the given array.
-    * `minlength`: Number, creates a [validator](./validation.html) that checks if the value length is not less than the given number
-    * `maxlength`: Number, creates a [validator](./validation.html) that checks if the value length is not greater than the given number
+    * `minLength`: Number, creates a [validator](./validation.html) that checks if the value length is not less than the given number
+    * `maxLength`: Number, creates a [validator](./validation.html) that checks if the value length is not greater than the given number
 
     <h5 id="number-validators">Number</h5>
 
diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index 765499355d6..a63a2f468de 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -88,12 +88,13 @@ Object.defineProperty(SchemaStringOptions.prototype, 'uppercase', opts);
  * string's `length` is at least the given number.
  *
  * @api public
- * @property minlength
+ * @property minLength
  * @memberOf SchemaStringOptions
  * @type Number
  * @instance
  */
 
+Object.defineProperty(SchemaStringOptions.prototype, 'minLength', opts);
 Object.defineProperty(SchemaStringOptions.prototype, 'minlength', opts);
 
 /**
@@ -101,16 +102,17 @@ Object.defineProperty(SchemaStringOptions.prototype, 'minlength', opts);
  * string's `length` is at most the given number.
  *
  * @api public
- * @property maxlength
+ * @property maxLength
  * @memberOf SchemaStringOptions
  * @type Number
  * @instance
  */
 
+Object.defineProperty(SchemaStringOptions.prototype, 'maxLength', opts);
 Object.defineProperty(SchemaStringOptions.prototype, 'maxlength', opts);
 
 /*!
  * ignore
  */
 
-module.exports = SchemaStringOptions;
\ No newline at end of file
+module.exports = SchemaStringOptions;
diff --git a/lib/schema/string.js b/lib/schema/string.js
index a3bfaf4ea57..c4e3e6d8a6f 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -414,6 +414,8 @@ SchemaString.prototype.minlength = function(value, message) {
   return this;
 };
 
+SchemaString.prototype.minLength = SchemaString.prototype.minlength;
+
 /**
  * Sets a maximum length validator.
  *
@@ -468,6 +470,8 @@ SchemaString.prototype.maxlength = function(value, message) {
   return this;
 };
 
+SchemaString.prototype.maxLength = SchemaString.prototype.maxlength;
+
 /**
  * Sets a regexp validator.
  *
diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index f690a96cc73..7e904526aa5 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -60,7 +60,7 @@ describe('validation docs', function() {
    *
    * - All [SchemaTypes](./schematypes.html) have the built-in [required](./api.html#schematype_SchemaType-required) validator. The required validator uses the [SchemaType's `checkRequired()` function](./api.html#schematype_SchemaType-checkRequired) to determine if the value satisfies the required validator.
    * - [Numbers](./api.html#schema-number-js) have [`min` and `max`](./schematypes.html#number-validators) validators.
-   * - [Strings](./api.html#schema-string-js) have [`enum`, `match`, `minlength`, and `maxlength`](./schematypes.html#string-validators) validators.
+   * - [Strings](./api.html#schema-string-js) have [`enum`, `match`, `minLength`, and `maxLength`](./schematypes.html#string-validators) validators.
    *
    * Each of the validator links above provide more information about how to enable them and customize their error messages.
    */
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 0496b77a716..34c9c9f7127 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -98,23 +98,26 @@ describe('ValidationError', function() {
     });
   });
 
-  describe('#minlength', function() {
+  describe('#minLength', function() {
     it('causes a validation error', function(done) {
       const AddressSchema = new Schema({
-        postalCode: { type: String, minlength: 5 }
+        postalCode: { type: String, minlength: 5 },
+        zipCode: { type: String, minLength: 5 }
       });
 
       const Address = mongoose.model('MinLengthAddress', AddressSchema);
 
       const model = new Address({
-        postalCode: '9512'
+        postalCode: '9512',
+        zipCode: '9512'
       });
 
       // should fail validation
       model.validate(function(err) {
-        assert.notEqual(err, null, 'String minlegth validation failed.');
+        assert.notEqual(err, null, 'String minLength validation failed.');
         assert.ok(err.message.startsWith('MinLengthAddress validation failed'));
         model.postalCode = '95125';
+        model.zipCode = '95125';
 
         // should pass validation
         model.validate(function(err) {
@@ -133,13 +136,15 @@ describe('ValidationError', function() {
       };
 
       const AddressSchema = new Schema({
-        postalCode: { type: String, minlength: 5 }
+        postalCode: { type: String, minlength: 5 },
+        zipCode: { type: String, minLength: 5 }
       });
 
       const Address = mongoose.model('gh4207', AddressSchema);
 
       const model = new Address({
-        postalCode: '9512'
+        postalCode: '9512',
+        zipCode: '9512'
       });
 
       // should fail validation
@@ -152,23 +157,26 @@ describe('ValidationError', function() {
     });
   });
 
-  describe('#maxlength', function() {
+  describe('#maxLength', function() {
     it('causes a validation error', function(done) {
       const AddressSchema = new Schema({
-        postalCode: { type: String, maxlength: 10 }
+        postalCode: { type: String, maxlength: 10 },
+        zipCode: { type: String, maxLength: 10 }
       });
 
       const Address = mongoose.model('MaxLengthAddress', AddressSchema);
 
       const model = new Address({
-        postalCode: '95125012345'
+        postalCode: '95125012345',
+        zipCode: '95125012345'
       });
 
       // should fail validation
       model.validate(function(err) {
-        assert.notEqual(err, null, 'String maxlegth validation failed.');
+        assert.notEqual(err, null, 'String maxLength validation failed.');
         assert.ok(err.message.startsWith('MaxLengthAddress validation failed'));
         model.postalCode = '95125';
+        model.zipCode = '95125';
 
         // should pass validation
         model.validate(function(err) {

From aee55071af3cc321ab57228ac679ba91e78db7ee Mon Sep 17 00:00:00 2001
From: Vishal Gauba <vishal.gauba@gmail.com>
Date: Sat, 7 Nov 2020 23:17:46 +0530
Subject: [PATCH 1340/2348] feat(debug): #8963 `shell` option for date format
 (ISODate)

---
 docs/faq.pug                                  |  3 +
 lib/drivers/node-mongodb-native/collection.js | 24 ++++---
 test/debug.test.js                            | 72 +++++++++++++++++++
 3 files changed, 90 insertions(+), 9 deletions(-)
 create mode 100644 test/debug.test.js

diff --git a/docs/faq.pug b/docs/faq.pug
index 37269ea197d..188c00192c8 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -300,6 +300,9 @@ block content
     
     // disable colors in debug mode
     mongoose.set('debug', { color: false })
+
+    // get mongodb-shell friendly output (ISODate)
+    mongoose.set('debug', { shell: true })
     ```
 
     All executed collection methods will log output of their arguments to your
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index d660c7de51c..1219d07e921 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -168,7 +168,9 @@ function iter(i) {
       } else if (debug instanceof stream.Writable) {
         this.$printToStream(_this.name, i, args, debug);
       } else {
-        this.$print(_this.name, i, args, typeof debug.color === 'undefined' ? true : debug.color);
+        const color = debug.color == null ? true : debug.color;
+        const shell = debug.shell == null ? false : debug.shell;
+        this.$print(_this.name, i, args, color, shell);
       }
     }
 
@@ -213,13 +215,13 @@ for (const key of Object.keys(Collection.prototype)) {
  * @method $print
  */
 
-NativeCollection.prototype.$print = function(name, i, args, color) {
+NativeCollection.prototype.$print = function(name, i, args, color, shell) {
   const moduleName = color ? '\x1B[0;36mMongoose:\x1B[0m ' : 'Mongoose: ';
   const functionCall = [name, i].join('.');
   const _args = [];
   for (let j = args.length - 1; j >= 0; --j) {
     if (this.$format(args[j]) || _args.length) {
-      _args.unshift(this.$format(args[j], color));
+      _args.unshift(this.$format(args[j], color, shell));
     }
   }
   const params = '(' + _args.join(', ') + ')';
@@ -254,10 +256,10 @@ NativeCollection.prototype.$printToStream = function(name, i, args, stream) {
  * @method $format
  */
 
-NativeCollection.prototype.$format = function(arg, color) {
+NativeCollection.prototype.$format = function(arg, color, shell) {
   const type = typeof arg;
   if (type === 'function' || type === 'undefined') return '';
-  return format(arg, false, color);
+  return format(arg, false, color, shell);
 };
 
 /*!
@@ -279,10 +281,14 @@ function map(o) {
 function formatObjectId(x, key) {
   x[key] = inspectable('ObjectId("' + x[key].toHexString() + '")');
 }
-function formatDate(x, key) {
-  x[key] = inspectable('new Date("' + x[key].toUTCString() + '")');
+function formatDate(x, key, shell) {
+  if (shell) {
+    x[key] = inspectable('ISODate("' + x[key].toUTCString() + '")');
+  } else {
+    x[key] = inspectable('new Date("' + x[key].toUTCString() + '")');
+  }
 }
-function format(obj, sub, color) {
+function format(obj, sub, color, shell) {
   if (obj && typeof obj.toBSON === 'function') {
     obj = obj.toBSON();
   }
@@ -326,7 +332,7 @@ function format(obj, sub, color) {
         } else if (x[key].constructor.name === 'ObjectID') {
           formatObjectId(x, key);
         } else if (x[key].constructor.name === 'Date') {
-          formatDate(x, key);
+          formatDate(x, key, shell);
         } else if (x[key].constructor.name === 'ClientSession') {
           x[key] = inspectable('ClientSession("' +
             get(x[key], 'id.id.buffer', '').toString('hex') + '")');
diff --git a/test/debug.test.js b/test/debug.test.js
new file mode 100644
index 00000000000..0aee13b6aa4
--- /dev/null
+++ b/test/debug.test.js
@@ -0,0 +1,72 @@
+'use strict';
+
+/**
+ * Test dependencies.
+ */
+
+const assert = require('assert');
+const start = require('./common');
+
+const mongoose = start.mongoose;
+const Schema = mongoose.Schema;
+
+/**
+ * Setup.
+ */
+
+const testSchema = new Schema({
+  dob: Date
+}, {
+  timestamps: {
+    createdAt: 'created_at'
+  }
+});
+
+
+/**
+ * Test.
+ */
+
+describe('debug: shell', function() {
+  let db;
+  let testModel;
+
+  let lastLog;
+  let originalConsole = console.info;
+  let originalDebugOption = mongoose.options.debug
+
+  before(function(done) {
+    db = start();
+    testModel = db.model('Test', testSchema);
+
+    // monkey patch to read debug output
+    console.info = function() {
+      lastLog = arguments[0];
+      if (originalDebugOption) {
+        originalConsole.apply(console, arguments);
+      };
+    }
+
+    done();
+  });
+
+  after(function(done) {
+    // revert monkey patch
+    console.info = originalConsole;
+    mongoose.set('debug', originalDebugOption)
+    db.close(done);
+  });
+
+  it('no-shell', async function() {
+    mongoose.set('debug', {shell: false});
+    await testModel.create({dob: new Date()});
+    assert.equal(true, lastLog.includes('new Date'));
+  });
+
+  it('shell', async function() {
+    mongoose.set('debug', {shell: true});
+    await testModel.create({dob: new Date()});
+    assert.equal(true, lastLog.includes('ISODate'));
+  });
+
+});

From 47815b812117046a11ed14b9938dc90392b39715 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Nov 2020 10:54:01 -0500
Subject: [PATCH 1341/2348] test(typescript): add model inheritance example
 from user feedback

Re: #8108
---
 test/typescript/main.test.js        |  8 ++++++++
 test/typescript/modelInheritance.ts | 13 +++++++++++++
 2 files changed, 21 insertions(+)
 create mode 100644 test/typescript/modelInheritance.ts

diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 870ea9c9c89..d09140367ee 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -111,6 +111,14 @@ describe('typescript syntax', function() {
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.includes('Property \'notAFunction\' does not exist'), errors[0].messageText);
   });
+
+  it('model inheritance', function() {
+    const errors = runTest('modelInheritance.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/modelInheritance.ts b/test/typescript/modelInheritance.ts
new file mode 100644
index 00000000000..0a720836617
--- /dev/null
+++ b/test/typescript/modelInheritance.ts
@@ -0,0 +1,13 @@
+import { Model } from 'mongoose';
+
+class InteractsWithDatabase extends Model {
+  async _update(): Promise<void> {
+    await this.save();
+  }
+}
+
+class SourceProvider extends InteractsWithDatabase {
+  static async deleteInstallation (installationId: number): Promise<void> {
+    await this.findOneAndDelete({ installationId });
+  }
+}
\ No newline at end of file

From 19bd0ff7c94652dba3ba84546a80abcfd19e6137 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Nov 2020 11:24:35 -0500
Subject: [PATCH 1342/2348] docs(SchemaStringOptions): add note about alternate
 spellings for minLength / maxLength

---
 lib/options/SchemaStringOptions.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index a63a2f468de..8e08850ca3e 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -87,6 +87,10 @@ Object.defineProperty(SchemaStringOptions.prototype, 'uppercase', opts);
  * If set, Mongoose will add a custom validator that ensures the given
  * string's `length` is at least the given number.
  *
+ * Mongoose supports two different spellings for this option: `minLength` and `minlength`.
+ * `minLength` is the recommended way to specify this option, but Mongoose also supports
+ * `minlength` (lowercase "l").
+ *
  * @api public
  * @property minLength
  * @memberOf SchemaStringOptions
@@ -101,6 +105,10 @@ Object.defineProperty(SchemaStringOptions.prototype, 'minlength', opts);
  * If set, Mongoose will add a custom validator that ensures the given
  * string's `length` is at most the given number.
  *
+ * Mongoose supports two different spellings for this option: `maxLength` and `maxlength`.
+ * `maxLength` is the recommended way to specify this option, but Mongoose also supports
+ * `maxlength` (lowercase "l").
+ *
  * @api public
  * @property maxLength
  * @memberOf SchemaStringOptions

From af6fb1b1b3b246c4cd340646b5e7e2c56d877b59 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Nov 2020 11:58:46 -0500
Subject: [PATCH 1343/2348] docs(CONTRIBUTING): remove mmapv1 recommendation
 and clean up a few other details

Fix #9529
---
 CONTRIBUTING.md | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 6be7da984bd..251afd81e83 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -6,22 +6,21 @@ If you have a question about Mongoose (not a bug report) please post it to eithe
 
 - Before opening a new issue, look for existing [issues](https://github.com/Automattic/mongoose/issues) to avoid duplication. If the issue does not yet exist, [create one](https://github.com/Automattic/mongoose/issues/new).
   - Please post any relevant code samples, preferably a standalone script that
-  reproduces your issue. Do **not** describe your issue in prose, show your
-  code.
+  reproduces your issue. Do **not** describe your issue in prose. **Show your code.**
   - If the bug involves an error, please post the stack trace.
-  - Please post the version of mongoose and mongodb that you're using.
-  - Please write bug reports in JavaScript (ES5, ES6, etc) that runs in Node.js, not coffeescript, typescript, etc.
+  - Please post the version of Mongoose and MongoDB that you're using.
+  - Please write bug reports in JavaScript (ES5, ES6, etc) that runs in Node.js, **not** CoffeeScript, TypeScript, JSX, etc.
 
 ### Requesting new features
 
 - Before opening a new issue, look for existing [issues](https://github.com/learnboost/mongoose/issues) to avoid duplication. If the issue does not yet exist, [create one](https://github.com/learnboost/mongoose/issues/new).
 - Please describe a use case for it
-- it would be ideal to include test cases as well
+- Please include test cases if possible
 
 ### Fixing bugs / Adding features
 
 - Before starting to write code, look for existing [issues](https://github.com/learnboost/mongoose/issues). That way you avoid working on something that might not be of interest or that has been addressed already in a different branch. You can create a new issue [here](https://github.com/learnboost/mongoose/issues/new).
-  - _The source of this project is written in javascript, not coffeescript or typescript. Please write your bug reports in JavaScript that can run in vanilla Node.js_.
+  - _The source of this project is written in JavaScript, not CoffeeScript or TypeScript. Please write your bug reports in JavaScript that can run in vanilla Node.js_.
 - Fork the [repo](https://github.com/Automattic/mongoose) _or_ for small documentation changes, navigate to the source on github and click the [Edit](https://github.com/blog/844-forking-with-the-edit-button) button.
 - Follow the general coding style of the rest of the project:
   - 2 space tabs
@@ -37,7 +36,7 @@ If you have a question about Mongoose (not a bug report) please post it to eithe
 ### Running the tests
 - Open a terminal and navigate to the root of the project
 - execute `npm install` to install the necessary dependencies
-- start a mongodb instance on port 27017 if one isn't running already. `mongod --dbpath <path to store data> --port 27017 --storageEngine mmapv1`. Mongoose tests run much faster on the mmapv1 storage engine as opposed to the WiredTiger storage engine.
+- start a MongoDB instance on port 27017 if one isn't running already. `mongod --dbpath <path to store data>`. We typically use [MongoDB Enterprise](https://www.mongodb.com/try/download/enterprise) with the [in-memory storage engine](https://docs.mongodb.com/manual/core/inmemory/) in order to run tests faster.
 - execute `npm test` to run the tests (we're using [mocha](http://mochajs.org/))
   - or to execute a single test `npm test -- -g 'some regexp that matches the test description'`
   - any mocha flags can be specified with `-- <mocha flags here>`
@@ -84,9 +83,3 @@ Thank you to all our backers! [[Become a backer](https://opencollective.com/mong
 
 <a href="https://opencollective.com/mongoose#backers" target="_blank"><img src="https://opencollective.com/mongoose/backers.svg?width=890"></a>
 
-
-### Sponsors
-
-Thank you to all our sponsors! (please ask your company to also support this open source project by [becoming a sponsor](https://opencollective.com/mongoose#sponsor))
-
-<a href="https://mixmax.com" target="_blank"><img src="http://mongoosejs.com/docs/images/mixmax.png"></a>

From d4d3e63d61e39ce3ff5aaf0e836f089f2bf88e5c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Nov 2020 12:10:56 -0500
Subject: [PATCH 1344/2348] test(update): repro #9537

---
 test/model.update.test.js | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 4339746195b..5e3d7601a81 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3328,19 +3328,29 @@ describe('model: updateOne: ', function() {
     });
   });
 
-  it('moves $set of immutable properties to $setOnInsert (gh-8467)', function() {
+  it('moves $set of immutable properties to $setOnInsert (gh-8467) (gh-9537)', function() {
+    const childSchema = Schema({ name: String });
     const Model = db.model('Test', Schema({
       name: String,
-      age: { type: Number, default: 25, immutable: true }
+      age: { type: Number, default: 25, immutable: true },
+      child: { type: childSchema, immutable: true }
     }));
 
     const _opts = { upsert: true, setDefaultsOnInsert: true };
 
     return co(function*() {
-      yield Model.updateOne({ name: 'John' }, { name: 'John', age: 20 }, _opts);
+      yield Model.deleteMany({});
+      yield Model.updateOne({}, { name: 'John', age: 20, child: { name: 'test' } }, _opts);
 
       const doc = yield Model.findOne().lean();
       assert.equal(doc.age, 20);
+      assert.equal(doc.name, 'John');
+      assert.equal(doc.child.name, 'test');
+
+      yield Model.updateOne({}, { name: 'new', age: 29, child: { name: 'new' } }, _opts);
+      assert.equal(doc.age, 20);
+      assert.equal(doc.name, 'John');
+      assert.equal(doc.child.name, 'test');
     });
   });
 

From 537f974cf1720b66dedb4a7d8162b881c2ba65d2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Nov 2020 12:11:15 -0500
Subject: [PATCH 1345/2348] fix(update): handle casting immutable object
 properties with `$setOnInsert`

Fix #9537
Re: #8467
---
 lib/helpers/query/castUpdate.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 8afd60af8f7..bf60e5d11b7 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -203,7 +203,8 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
       // watch for embedded doc schemas
       schematype = schema._getSchema(prefix + key);
 
-      if (handleImmutable(schematype, strict, obj, key, prefix + key, context)) {
+      if (op !== '$setOnInsert' &&
+          handleImmutable(schematype, strict, obj, key, prefix + key, context)) {
         continue;
       }
 

From f7dc628a10284938001e3113e27e850505a6ba3d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Nov 2020 15:21:54 -0500
Subject: [PATCH 1346/2348] test(discriminator): repro #9534

---
 test/model.discriminator.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 89cd2abae27..ad37c1ee187 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1615,6 +1615,21 @@ describe('model', function() {
     assert.equal(doc.view.clickCount, 1);
   });
 
+  it('overwrites if discriminator schema sets a path to single nested but base schema sets to doc array (gh-9354)', function() {
+    const A = db.model('Test', Schema({
+      prop: [{ reqProp: { type: String, required: true } }]
+    }));
+
+    const B = A.discriminator('Test2', Schema({
+      prop: Schema({ name: String })
+    }));
+
+    assert.ok(!B.schema.path('prop').schema.path('reqProp'));
+
+    const doc = new B({ prop: { name: 'test' } });
+    return doc.validate();
+  });
+
   it('can use compiled model schema as a discriminator (gh-9238)', function() {
     const SmsSchema = new mongoose.Schema({ senderNumber: String });
     const EmailSchema = new mongoose.Schema({ fromEmailAddress: String });

From e5eaed8cf0dd29c0b1579003dd3777cb3336d29e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Nov 2020 15:24:07 -0500
Subject: [PATCH 1347/2348] fix(discriminator): overwrite instead of merge if
 discriminator schema specifies a path is single nested but base schema has
 path as doc array

Fix #9534
---
 lib/helpers/model/discriminator.js | 2 ++
 lib/utils.js                       | 9 ++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index cfacd3d3dfc..2ad4c5e3754 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -85,6 +85,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     for (const path of baseSchemaPaths) {
       if (schema.nested[path]) {
         conflictingPaths.push(path);
+        continue;
       }
 
       if (path.indexOf('.') === -1) {
@@ -102,6 +103,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     }
 
     utils.merge(schema, baseSchema, {
+      isDiscriminatorSchemaMerge: true,
       omit: { discriminators: true, base: true },
       omitNested: conflictingPaths.reduce((cur, path) => {
         cur['tree.' + path] = true;
diff --git a/lib/utils.js b/lib/utils.js
index fceaec681e3..48b29aa567c 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -259,7 +259,14 @@ exports.merge = function merge(to, from, options, path) {
         to[key] = {};
       }
       if (from[key] != null) {
-        if (from[key].instanceOfSchema) {
+        // Skip merging schemas if we're creating a discriminator schema and
+        // base schema has a given path as a single nested but discriminator schema
+        // has the path as a document array, or vice versa (gh-9534)
+        if (options.isDiscriminatorSchemaMerge &&
+            (from[key].$isSingleNested && to[key].$isMongooseDocumentArray) ||
+            (from[key].$isMongooseDocumentArray && to[key].$isSingleNested)) {
+          continue;
+        } else if (from[key].instanceOfSchema) {
           if (to[key].instanceOfSchema) {
             to[key].add(from[key].clone());
           } else {

From c83999b3b792d540763fb0b2dd61173730fbac3d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 12 Nov 2020 16:37:34 -0500
Subject: [PATCH 1348/2348] chore: release 5.10.14

---
 History.md   | 8 ++++++++
 package.json | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index e5212708f83..8999e984490 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,11 @@
+5.10.14 / 2020-11-12
+====================
+ * fix(update): handle casting immutable object properties with `$setOnInsert` #9537
+ * fix(discriminator): overwrite instead of merge if discriminator schema specifies a path is single nested but base schema has path as doc array #9534
+ * docs(middleware): clarify that you need to set both `document` and `query` on `remove` hooks to get just document middleware #9530 [mustafaKamal-fe](https://github.com/mustafaKamal-fe)
+ * docs(CONTRIBUTING): remove mmapv1 recommendation and clean up a few other details #9529
+ * refactor: remove duplicate function definition #9527 [ksullivan](https://github.com/ksullivan)
+
 5.10.13 / 2020-11-06
 ====================
  * fix: upgrade mongodb driver -> 3.6.3 for Lambda cold start fixes #9521 #9179 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index c4576415952..522357f420d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.13",
+  "version": "5.10.14",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9938ccf2fb9e55791d0c76d178f56add1a4456bb Mon Sep 17 00:00:00 2001
From: jonathan-wilkinson
 <41024180+jonathan-wilkinson@users.noreply.github.com>
Date: Fri, 13 Nov 2020 11:20:59 +0000
Subject: [PATCH 1349/2348] fix(document): make transform work with nested
 paths

---
 lib/document.js       |  2 +-
 test/document.test.js | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 9e8cb9abe67..d8c49ce4705 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3536,7 +3536,7 @@ function applySchemaTypeTransforms(self, json) {
       const val = self.get(path);
       const transformedValue = schematype.options.transform.call(self, val);
       throwErrorIfPromise(path, transformedValue);
-      json[path] = transformedValue;
+      utils.setValue(path, transformedValue, json);
     } else if (schematype.$embeddedSchemaType != null &&
         typeof schematype.$embeddedSchemaType.options.transform === 'function') {
       const vals = [].concat(self.get(path));
diff --git a/test/document.test.js b/test/document.test.js
index e935846d881..a7f20f6fc67 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8692,6 +8692,25 @@ describe('document', function() {
     assert.equal(doc.toObject({ transform: true }).arr[0].myDate, '2017');
   });
 
+  it('transforms nested paths (gh-9543)', function() {
+    const schema = Schema({
+      nested: {
+        date: {
+          type: Date,
+          transform: v => v.getFullYear()
+        }
+      }
+    });
+    const Model = db.model('Test', schema);
+
+    const doc = new Model({
+      nested: {
+        date: new Date('2020-01-01')
+      }
+    });
+    assert.equal(doc.toObject({ transform: true }).nested.date, '2020');
+  });
+
   it('handles setting numeric paths with single nested subdocs (gh-8583)', function() {
     const placedItemSchema = Schema({ image: String }, { _id: false });
 

From 288790dd7ef1dcd52fbd452e80b65b1a84c766e4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Nov 2020 11:02:43 -0500
Subject: [PATCH 1350/2348] test: clean up timezone issue with #9544 re: #9543

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index a7f20f6fc67..fe6ed0ea64f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8705,7 +8705,7 @@ describe('document', function() {
 
     const doc = new Model({
       nested: {
-        date: new Date('2020-01-01')
+        date: new Date('2020-06-01')
       }
     });
     assert.equal(doc.toObject({ transform: true }).nested.date, '2020');

From 3d9c4e6fb74eb403e4a0f06a6e8771b0d1622baa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Nov 2020 11:09:51 -0500
Subject: [PATCH 1351/2348] fix(schema): remove warning re: `increment` as a
 schema path name

Fix #9538
---
 lib/model.js  | 10 ++++++----
 lib/schema.js | 12 ------------
 2 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index de7ab0a26a4..68c9649575d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -575,10 +575,10 @@ function operand(self, where, delta, data, val, op) {
     self.$__.version = VERSION_INC;
   } else if (/^\$p/.test(op)) {
     // potentially changing array positions
-    self.increment();
+    increment.call(self);
   } else if (Array.isArray(val)) {
     // $set an array
-    self.increment();
+    increment.call(self);
   } else if (/\.\d+\.|\.\d+$/.test(data.path)) {
     // now handling $set, $unset
     // subpath of array
@@ -862,10 +862,12 @@ Model.prototype.$__version = function(where, delta) {
  * @api public
  */
 
-Model.prototype.increment = function increment() {
+function increment() {
   this.$__.version = VERSION_ALL;
   return this;
-};
+}
+
+Model.prototype.increment = increment;
 
 /**
  * Returns a query object
diff --git a/lib/schema.js b/lib/schema.js
index 2abd0a01a28..db021696d57 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -593,14 +593,6 @@ reserved.schema =
 reserved.toObject =
 reserved.validate = 1;
 
-/*!
- * Document keys to print warnings for
- */
-
-const warnings = {};
-warnings.increment = '`increment` should not be used as a schema path name ' +
-    'unless you have disabled versioning.';
-
 /**
  * Gets/sets schema paths.
  *
@@ -650,10 +642,6 @@ Schema.prototype.path = function(path, obj) {
     throw new Error('`' + firstPieceOfPath + '` may not be used as a schema pathname');
   }
 
-  if (warnings[path]) {
-    console.log('WARN: ' + warnings[path]);
-  }
-
   if (typeof obj === 'object' && utils.hasUserDefinedProperty(obj, 'ref')) {
     validateRef(obj.ref, path);
   }

From 920148e95faaa795129522715220f57ce25eb064 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Nov 2020 11:49:44 -0500
Subject: [PATCH 1352/2348] chore(index.d.ts): add support for lean docs

Re: #8108
---
 index.d.ts                       | 10 ++++++----
 test/typescript/leanDocuments.ts | 23 +++++++++++++++++++++++
 test/typescript/main.test.js     | 10 ++++++++++
 3 files changed, 39 insertions(+), 4 deletions(-)
 create mode 100644 test/typescript/leanDocuments.ts

diff --git a/index.d.ts b/index.d.ts
index a4a2f28a70b..0593c30015d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -472,10 +472,10 @@ declare module "mongoose" {
     set(value: any): this;
 
     /** The return value of this method is used in calls to JSON.stringify(doc). */
-    toJSON(options?: ToObjectOptions): any;
+    toJSON(options?: ToObjectOptions): LeanDocument<this>;
 
     /** Converts this document into a plain-old JavaScript object ([POJO](https://masteringjs.io/tutorials/fundamentals/pojo)). */
-    toObject(options?: ToObjectOptions): any;
+    toObject(options?: ToObjectOptions): LeanDocument<this>;
 
     /** Clears the modified state on the specified path. */
     unmarkModified(path: string);
@@ -1480,7 +1480,7 @@ declare module "mongoose" {
     j(val: boolean | null): this;
 
     /** Sets the lean option. */
-    lean(val?: boolean | any): this;
+    lean(val?: boolean | any): Query<LeanDocument<DocType>, DocType>;
 
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
@@ -1702,7 +1702,9 @@ declare module "mongoose" {
   
   export type UpdateQuery<T> = mongodb.UpdateQuery<T> & mongodb.MatchKeysAndValues<T>;
 
-  export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>
+  export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;
+
+  export type LeanDocument<T> = Omit<T, Exclude<keyof Document, '_id'>>;
 
   class QueryCursor<DocType extends Document> extends stream.Readable {
     /**
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
new file mode 100644
index 00000000000..0f72217e1a9
--- /dev/null
+++ b/test/typescript/leanDocuments.ts
@@ -0,0 +1,23 @@
+import { Schema, model, Document, Types } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Document {
+  _id?: Types.ObjectId,
+  name?: string;
+}
+
+const Test = model<ITest>('Test', schema);
+
+void async function main() {
+  const doc: ITest = await Test.findOne();
+
+  const pojo = doc.toObject();
+  await pojo.save();
+
+  const _doc = await Test.findOne().lean();
+  await _doc.save();
+
+  const hydrated = Test.hydrate(_doc);
+  await hydrated.save();
+}();
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index d09140367ee..b9bb974f77a 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -119,6 +119,16 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('lean documents', function() {
+    const errors = runTest('leanDocuments.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 2);
+    assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
+    assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
+  });
 });
 
 function runTest(file) {

From cc70256d4149a9835143ad7566c01db71978e9f1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Nov 2020 17:17:12 -0500
Subject: [PATCH 1353/2348] fix(array): make sure `Array#toObject()` returns a
 vanilla JavaScript array in Node.js 6+

Fix #9540
---
 lib/types/core_array.js  |  6 ++++--
 test/types.array.test.js | 21 +++++++++++++++++++--
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 954df521cc7..15d90978f66 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -869,14 +869,16 @@ class CoreMongooseArray extends Array {
     if (options && options.depopulate) {
       options = utils.clone(options);
       options._isNested = true;
-      return this.map(function(doc) {
+      // Ensure return value is a vanilla array, because in Node.js 6+ `map()`
+      // is smart enough to use the inherited array's constructor.
+      return [].concat(this).map(function(doc) {
         return doc instanceof Document
           ? doc.toObject(options)
           : doc;
       });
     }
 
-    return this.slice();
+    return [].concat(this);
   }
 
   /**
diff --git a/test/types.array.test.js b/test/types.array.test.js
index f2f8aeacee4..dfb8f145ad9 100644
--- a/test/types.array.test.js
+++ b/test/types.array.test.js
@@ -379,12 +379,12 @@ describe('types array', function() {
           const removed = doc.numbers.splice(1, 1, '10');
           assert.deepEqual(removed, [5]);
           assert.equal(typeof doc.numbers[1], 'number');
-          assert.deepEqual(doc.numbers.toObject(), [4, 10, 6, 7]);
+          assert.deepStrictEqual(doc.numbers.toObject(), [4, 10, 6, 7]);
           doc.save(function(err) {
             assert.ifError(err);
             A.findById(a._id, function(err, doc) {
               assert.ifError(err);
-              assert.deepEqual(doc.numbers.toObject(), [4, 10, 6, 7]);
+              assert.deepStrictEqual(doc.numbers.toObject(), [4, 10, 6, 7]);
 
               A.collection.drop(function(err) {
                 assert.ifError(err);
@@ -1828,6 +1828,23 @@ describe('types array', function() {
       });
     });
 
+    it('toObject returns a vanilla JavaScript array (gh-9540)', function() {
+      const schema = new Schema({ arr: [Number] });
+      const M = db.model('Test', schema);
+
+      const doc = new M({ arr: [1, 2, 3] });
+
+      let arr = doc.arr.toObject();
+      assert.ok(Array.isArray(arr));
+      assert.equal(arr.constructor, Array);
+      assert.deepStrictEqual(arr, [1, 2, 3]);
+
+      arr = doc.arr.toObject({ depopulate: true });
+      assert.ok(Array.isArray(arr));
+      assert.equal(arr.constructor, Array);
+      assert.deepStrictEqual(arr, [1, 2, 3]);
+    });
+
     it('pushing top level arrays and subarrays works (gh-1073)', function(done) {
       const schema = new Schema({ em: [new Schema({ sub: [String] })] });
       const M = db.model('Test', schema);

From 222a69f030aa8dce3275c5ff3a71b29c3b510154 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 13 Nov 2020 17:48:06 -0500
Subject: [PATCH 1354/2348] fix(connection): make `disconnect()` stop Mongoose
 if it is trying to reconnect

Fix #9531
---
 lib/connection.js                             | 13 ++++++++++++-
 lib/drivers/node-mongodb-native/connection.js |  5 +++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 2d2e7fde818..167e71b865d 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1015,11 +1015,22 @@ Connection.prototype.close = function(force, callback) {
  */
 Connection.prototype._close = function(force, callback) {
   const _this = this;
+  const closeCalled = this._closeCalled;
   this._closeCalled = true;
 
   switch (this.readyState) {
     case STATES.disconnected:
-      callback();
+      if (closeCalled) {
+        callback();
+      } else {
+        this.doClose(force, function(err) {
+          if (err) {
+            return callback(err);
+          }
+          _this.onClose(force);
+          callback(null);
+        });
+      }
       break;
 
     case STATES.connected:
diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index 8041a881620..57421ad85d3 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -168,6 +168,11 @@ function listen(conn) {
  */
 
 NativeConnection.prototype.doClose = function(force, fn) {
+  if (this.client == null) {
+    process.nextTick(() => fn());
+    return this;
+  }
+
   this.client.close(force, (err, res) => {
     // Defer because the driver will wait at least 1ms before finishing closing
     // the pool, see https://github.com/mongodb-js/mongodb-core/blob/a8f8e4ce41936babc3b9112bf42d609779f03b39/lib/connection/pool.js#L1026-L1030.

From 6ad012aaab3db406b36a792bda6a1795aeb7d301 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Nov 2020 06:50:55 +0200
Subject: [PATCH 1355/2348] test(schema): repro #9546 string enum

---
 test/schema.validation.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index c2929b8fb1f..b44c129c9ca 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -1369,5 +1369,23 @@ describe('schema', function() {
         done();
       });
     });
+    describe('`enum` accepts an object to support TypeScript enums (gh-9546) (gh-9535)', function() {
+      it('strings', function() {
+        const userSchema = new Schema({
+          name: {
+            type: String,
+            enum: {
+              hafez: 'Hafez',
+              nada: 'Nada'
+            }
+          }
+        });
+
+        const User = mongoose.model('User_gh9546_1', userSchema);
+        const user = new User({ name: 'Ameen' });
+        const err = user.validateSync();
+        assert.equal(err.message, 'User_gh9546_1 validation failed: name: `Ameen` is not a valid enum value for path `name`.');
+      });
+    });
   });
 });

From 7b100afca26309bab2886dbdd918f4b7ad8dea3a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Nov 2020 06:51:28 +0200
Subject: [PATCH 1356/2348] feat(schema): make schema enum accept TypeScript
 enum objects

---
 lib/schema/string.js | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/schema/string.js b/lib/schema/string.js
index a3bfaf4ea57..f97e91c3759 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -217,8 +217,13 @@ SchemaString.prototype.enum = function() {
   let errorMessage;
 
   if (utils.isObject(arguments[0])) {
-    values = arguments[0].values;
-    errorMessage = arguments[0].message;
+    if (Array.isArray(arguments[0].values)) {
+      values = arguments[0].values;
+      errorMessage = arguments[0].message;
+    } else {
+      values = Object.values(arguments[0]);
+      errorMessage = MongooseError.messages.String.enum;
+    }
   } else {
     values = arguments;
     errorMessage = MongooseError.messages.String.enum;

From ba4c12f43b917940abf97ef4a26228c595a48edf Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Nov 2020 07:01:19 +0200
Subject: [PATCH 1357/2348] feat(SchemaNumber): support POJOs as enum for
 TypeScript enum support

Fix #9546
---
 lib/schema/number.js           |  7 ++++++-
 test/schema.validation.test.js | 27 +++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/lib/schema/number.js b/lib/schema/number.js
index 719a1aa80f2..ac0c3f11cf0 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -310,8 +310,13 @@ SchemaNumber.prototype.enum = function(values, message) {
     }, this);
   }
 
+
   if (!Array.isArray(values)) {
-    values = Array.prototype.slice.call(arguments);
+    if (utils.isObject(values)) {
+      values = Object.values(values);
+    } else {
+      values = Array.prototype.slice.call(arguments);
+    }
     message = MongooseError.messages.Number.enum;
   }
 
diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index b44c129c9ca..5ec258eb25c 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -1371,6 +1371,7 @@ describe('schema', function() {
     });
     describe('`enum` accepts an object to support TypeScript enums (gh-9546) (gh-9535)', function() {
       it('strings', function() {
+        // Arrange
         const userSchema = new Schema({
           name: {
             type: String,
@@ -1382,10 +1383,36 @@ describe('schema', function() {
         });
 
         const User = mongoose.model('User_gh9546_1', userSchema);
+
+        // Act
         const user = new User({ name: 'Ameen' });
         const err = user.validateSync();
+
+        // Assert
         assert.equal(err.message, 'User_gh9546_1 validation failed: name: `Ameen` is not a valid enum value for path `name`.');
       });
+
+      it('numbers', function() {
+        // Arrange
+        const userSchema = new Schema({
+          status: {
+            type: Number,
+            enum: {
+              0: 0,
+              1: 1
+            }
+          }
+        });
+
+        const User = mongoose.model('User_gh9546_2', userSchema);
+
+        // Act
+        const user = new User({ status: 2 });
+        const err = user.validateSync();
+
+        // Assert
+        assert.equal(err.message, 'User_gh9546_2 validation failed: status: `2` is not a valid enum value for path `status`.');
+      });
     });
   });
 });

From f66b0a285704aa00f8472a80e7c70082b068dfc6 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Nov 2020 07:48:42 +0200
Subject: [PATCH 1358/2348] feat(SchemaArray): make schema array accept
 TypeScript enum object for an enum

---
 lib/schema/array.js            |  8 +++++++-
 test/schema.validation.test.js | 19 +++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 828eb1be09a..b51ddcf072f 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -242,7 +242,13 @@ SchemaArray.prototype.enum = function() {
     }
     break;
   }
-  arr.caster.enum.apply(arr.caster, arguments);
+
+  let enumArray = arguments;
+  if (!Array.isArray(arguments) && utils.isObject(arguments)) {
+    enumArray = Object.values(enumArray);
+  }
+
+  arr.caster.enum.apply(arr.caster, enumArray);
   return this;
 };
 
diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index 5ec258eb25c..9d349a0bed1 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -1413,6 +1413,25 @@ describe('schema', function() {
         // Assert
         assert.equal(err.message, 'User_gh9546_2 validation failed: status: `2` is not a valid enum value for path `status`.');
       });
+
+      it('arrays', function() {
+        // Arrange
+        const userSchema = new Schema({
+          favoriteNumbers: {
+            type: [Number],
+            enum: { 1: 1, 2: 2 }
+          }
+        });
+
+        const User = mongoose.model('User_gh9546_3', userSchema);
+
+        // Act
+        const user = new User({ favoriteNumbers: [1, 10, 2, 20] });
+        const err = user.validateSync();
+
+        // Assert
+        assert.equal(err.message, 'User_gh9546_3 validation failed: favoriteNumbers.1: `10` is not a valid enum value for path `favoriteNumbers.1`., favoriteNumbers.3: `20` is not a valid enum value for path `favoriteNumbers.3`.');
+      });
     });
   });
 });

From 413c060d92c84268255a394f3c9963dbe2b58b0f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Nov 2020 07:53:43 +0200
Subject: [PATCH 1359/2348] test(schema): test happy scenario for enum objects

---
 test/schema.validation.test.js | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index 9d349a0bed1..1e773fea9ee 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -1432,6 +1432,39 @@ describe('schema', function() {
         // Assert
         assert.equal(err.message, 'User_gh9546_3 validation failed: favoriteNumbers.1: `10` is not a valid enum value for path `favoriteNumbers.1`., favoriteNumbers.3: `20` is not a valid enum value for path `favoriteNumbers.3`.');
       });
+
+      it('passes when using valid data', function() {
+        // Arrange
+        const userSchema = new Schema({
+          name: {
+            type: String,
+            enum: {
+              hafez: 'Hafez',
+              nada: 'Nada'
+            }
+          },
+          status: {
+            type: Number,
+            enum: {
+              0: 0,
+              1: 1
+            }
+          },
+          favoriteNumbers: {
+            type: [Number],
+            enum: { 1: 1, 2: 2 }
+          }
+        });
+
+        const User = mongoose.model('User_gh9546_4', userSchema);
+
+        // Act
+        const user = new User({ name: 'Hafez', status: 1, favoriteNumbers: [1, 2, 2, 2] });
+        const err = user.validateSync();
+
+        // Assert
+        assert.ifError(err);
+      });
     });
   });
 });

From 1f5a2bd54c5b7e328ad1c01ebbc624f03864cd2d Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 14 Nov 2020 08:15:43 +0200
Subject: [PATCH 1360/2348] fix: use utils.object.vals instead of Object.values
 for node v7-

---
 lib/schema/array.js  | 2 +-
 lib/schema/number.js | 2 +-
 lib/schema/string.js | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index b51ddcf072f..dc0f6bb1a32 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -245,7 +245,7 @@ SchemaArray.prototype.enum = function() {
 
   let enumArray = arguments;
   if (!Array.isArray(arguments) && utils.isObject(arguments)) {
-    enumArray = Object.values(enumArray);
+    enumArray = utils.object.vals(enumArray);
   }
 
   arr.caster.enum.apply(arr.caster, enumArray);
diff --git a/lib/schema/number.js b/lib/schema/number.js
index ac0c3f11cf0..862084ee393 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -313,7 +313,7 @@ SchemaNumber.prototype.enum = function(values, message) {
 
   if (!Array.isArray(values)) {
     if (utils.isObject(values)) {
-      values = Object.values(values);
+      values = utils.object.vals(values);
     } else {
       values = Array.prototype.slice.call(arguments);
     }
diff --git a/lib/schema/string.js b/lib/schema/string.js
index f97e91c3759..52d3eb91a43 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -221,7 +221,7 @@ SchemaString.prototype.enum = function() {
       values = arguments[0].values;
       errorMessage = arguments[0].message;
     } else {
-      values = Object.values(arguments[0]);
+      values = utils.object.vals(arguments[0]);
       errorMessage = MongooseError.messages.String.enum;
     }
   } else {

From d7c6ac0158be7c971db874c590bada17cdd4ac73 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Nov 2020 11:47:41 -0500
Subject: [PATCH 1361/2348] feat(document): support square bracket indexing for
 `get()` and `set()`

Fix #9375
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 522357f420d..0409ece2b35 100644
--- a/package.json
+++ b/package.json
@@ -23,7 +23,7 @@
     "kareem": "2.3.1",
     "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
-    "mpath": "0.7.0",
+    "mpath": "0.8.0",
     "mquery": "3.2.2",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",

From 032c47fbbaf21298a006acb1790ea45dabf45b0d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Nov 2020 11:49:47 -0500
Subject: [PATCH 1362/2348] chore(npmignore): remove History.md from published
 bundle

Fix #9404
---
 .npmignore | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.npmignore b/.npmignore
index 69deea027ae..ee24d516dbc 100644
--- a/.npmignore
+++ b/.npmignore
@@ -24,7 +24,7 @@ examples/
 .vscode
 .eslintignore
 CONTRIBUTING.md
-HISTORY.md
+History.md
 format_deps.js
 release-items.md
 static.js

From a659b2bf7df5513893679085784bba73a9c8b26a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Nov 2020 14:43:21 -0500
Subject: [PATCH 1363/2348] feat(populate+schema): add support for `populate`
 schematype option that sets default populate options

Fix #6029
---
 docs/schematypes.pug                          |  6 +++++
 .../populate/getModelsMapForPopulate.js       |  4 +++
 lib/options/SchemaNumberOptions.js            | 25 ++++++++++++++++++
 lib/options/SchemaObjectIdOptions.js          | 25 ++++++++++++++++++
 lib/options/SchemaStringOptions.js            | 12 +++++++++
 test/debug.test.js                            | 26 +++++++++----------
 test/model.populate.test.js                   | 23 ++++++++++++++++
 7 files changed, 108 insertions(+), 13 deletions(-)

diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 5b0b16fdc33..7d08ee24737 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -290,18 +290,24 @@ block content
     * `enum`: Array, creates a [validator](./validation.html) that checks if the value is in the given array.
     * `minLength`: Number, creates a [validator](./validation.html) that checks if the value length is not less than the given number
     * `maxLength`: Number, creates a [validator](./validation.html) that checks if the value length is not greater than the given number
+    * `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
 
     <h5 id="number-validators">Number</h5>
 
     * `min`: Number, creates a [validator](./validation.html) that checks if the value is greater than or equal to the given minimum.
     * `max`: Number, creates a [validator](./validation.html) that checks if the value is less than or equal to the given maximum.
     * `enum`: Array, creates a [validator](./validation.html) that checks if the value is strictly equal to one of the values in the given array.
+    * `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
 
     <h5>Date</h5>
 
     * `min`: Date
     * `max`: Date
 
+    <h5>ObjectId</h5>
+
+    * `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
+
     <h3 id="usage-notes"><a href="#usage-notes">Usage Notes</a></h3>
 
     <h4 id="strings">String</h4>
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index baa76d8f190..a5bd38821be 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -67,6 +67,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     modelNames = null;
     let isRefPath = !!_firstWithRefPath;
     let normalizedRefPath = _firstWithRefPath ? get(_firstWithRefPath, 'options.refPath', null) : null;
+    let schemaOptions = null;
 
     if (Array.isArray(schema)) {
       const schemasArray = schema;
@@ -104,6 +105,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
         isRefPath = res.isRefPath;
         normalizedRefPath = res.refPath;
         justOne = res.justOne;
+        schemaOptions = get(schema, 'options.populate', null);
       } catch (error) {
         return error;
       }
@@ -319,6 +321,8 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
 
         if (isVirtual && get(virtual, 'options.options')) {
           currentOptions.options = utils.clone(virtual.options.options);
+        } else if (schemaOptions != null) {
+          currentOptions.options = Object.assign({}, schemaOptions);
         }
         utils.merge(currentOptions, options);
 
diff --git a/lib/options/SchemaNumberOptions.js b/lib/options/SchemaNumberOptions.js
index 42b0a01583d..38553fb78b1 100644
--- a/lib/options/SchemaNumberOptions.js
+++ b/lib/options/SchemaNumberOptions.js
@@ -67,6 +67,31 @@ Object.defineProperty(SchemaNumberOptions.prototype, 'max', opts);
 
 Object.defineProperty(SchemaNumberOptions.prototype, 'enum', opts);
 
+/**
+ * Sets default [populate options](/docs/populate.html#query-conditions).
+ *
+ * ####Example:
+ *     const schema = new Schema({
+ *       child: {
+ *         type: Number,
+ *         ref: 'Child',
+ *         populate: { select: 'name' }
+ *       }
+ *     });
+ *     const Parent = mongoose.model('Parent', schema);
+ *
+ *     // Automatically adds `.select('name')`
+ *     Parent.findOne().populate('child');
+ *
+ * @api public
+ * @property populate
+ * @memberOf SchemaNumberOptions
+ * @type Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaNumberOptions.prototype, 'populate', opts);
+
 /*!
  * ignore
  */
diff --git a/lib/options/SchemaObjectIdOptions.js b/lib/options/SchemaObjectIdOptions.js
index cf887d0b7fe..e07ed9ecc02 100644
--- a/lib/options/SchemaObjectIdOptions.js
+++ b/lib/options/SchemaObjectIdOptions.js
@@ -31,6 +31,31 @@ const opts = require('./propertyOptions');
 
 Object.defineProperty(SchemaObjectIdOptions.prototype, 'auto', opts);
 
+/**
+ * Sets default [populate options](/docs/populate.html#query-conditions).
+ *
+ * ####Example:
+ *     const schema = new Schema({
+ *       child: {
+ *         type: 'ObjectId',
+ *         ref: 'Child',
+ *         populate: { select: 'name' }
+ *       }
+ *     });
+ *     const Parent = mongoose.model('Parent', schema);
+ *
+ *     // Automatically adds `.select('name')`
+ *     Parent.findOne().populate('child');
+ *
+ * @api public
+ * @property populate
+ * @memberOf SchemaObjectIdOptions
+ * @type Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaObjectIdOptions.prototype, 'populate', opts);
+
 /*!
  * ignore
  */
diff --git a/lib/options/SchemaStringOptions.js b/lib/options/SchemaStringOptions.js
index 8e08850ca3e..380050c4096 100644
--- a/lib/options/SchemaStringOptions.js
+++ b/lib/options/SchemaStringOptions.js
@@ -119,6 +119,18 @@ Object.defineProperty(SchemaStringOptions.prototype, 'minlength', opts);
 Object.defineProperty(SchemaStringOptions.prototype, 'maxLength', opts);
 Object.defineProperty(SchemaStringOptions.prototype, 'maxlength', opts);
 
+/**
+ * Sets default [populate options](/docs/populate.html#query-conditions).
+ *
+ * @api public
+ * @property populate
+ * @memberOf SchemaStringOptions
+ * @type Object
+ * @instance
+ */
+
+Object.defineProperty(SchemaStringOptions.prototype, 'populate', opts);
+
 /*!
  * ignore
  */
diff --git a/test/debug.test.js b/test/debug.test.js
index 0aee13b6aa4..06fcb805d11 100644
--- a/test/debug.test.js
+++ b/test/debug.test.js
@@ -32,8 +32,8 @@ describe('debug: shell', function() {
   let testModel;
 
   let lastLog;
-  let originalConsole = console.info;
-  let originalDebugOption = mongoose.options.debug
+  const originalConsole = console.info;
+  const originalDebugOption = mongoose.options.debug;
 
   before(function(done) {
     db = start();
@@ -44,8 +44,8 @@ describe('debug: shell', function() {
       lastLog = arguments[0];
       if (originalDebugOption) {
         originalConsole.apply(console, arguments);
-      };
-    }
+      }
+    };
 
     done();
   });
@@ -53,20 +53,20 @@ describe('debug: shell', function() {
   after(function(done) {
     // revert monkey patch
     console.info = originalConsole;
-    mongoose.set('debug', originalDebugOption)
+    mongoose.set('debug', originalDebugOption);
     db.close(done);
   });
 
-  it('no-shell', async function() {
-    mongoose.set('debug', {shell: false});
-    await testModel.create({dob: new Date()});
-    assert.equal(true, lastLog.includes('new Date'));
+  it('no-shell', function() {
+    mongoose.set('debug', { shell: false });
+    return testModel.create({ dob: new Date() }).
+      then(() => assert.equal(true, lastLog.includes('new Date')));
   });
 
-  it('shell', async function() {
-    mongoose.set('debug', {shell: true});
-    await testModel.create({dob: new Date()});
-    assert.equal(true, lastLog.includes('ISODate'));
+  it('shell', function() {
+    mongoose.set('debug', { shell: true });
+    testModel.create({ dob: new Date() }).
+      then(() => assert.equal(true, lastLog.includes('ISODate')));
   });
 
 });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 0bc27992ec9..454ddaf45e7 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9819,4 +9819,27 @@ describe('model: populate:', function() {
       assert.strictEqual(res[1].linkedId, undefined);
     });
   });
+
+  it('supports default populate options (gh-6029)', function() {
+    const parentSchema = Schema({
+      child: {
+        type: 'ObjectId',
+        ref: 'Child',
+        populate: { select: 'name' }
+      }
+    });
+    const Parent = db.model('Parent', parentSchema);
+
+    const childSchema = new Schema({ name: String, age: Number });
+    const Child = db.model('Child', childSchema);
+
+    return co(function*() {
+      const child = yield Child.create({ name: 'my name', age: 30 });
+      yield Parent.create({ child: child._id });
+
+      const res = yield Parent.findOne().populate('child');
+      assert.equal(res.child.name, 'my name');
+      assert.strictEqual(res.child.age, void 0);
+    });
+  });
 });

From 21a2b1ebea41a63da8f06f1bfde136df4a044f41 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 14 Nov 2020 14:49:32 -0500
Subject: [PATCH 1364/2348] test: fix tests re: #6029 #8256

---
 test/schema.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 31ab92ac4be..a747e6c537f 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2149,7 +2149,7 @@ describe('schema', function() {
   it('SchemaStringOptions line up with schema/string (gh-8256)', function() {
     const SchemaStringOptions = require('../lib/options/SchemaStringOptions');
     const keys = Object.keys(SchemaStringOptions.prototype).
-      filter(key => key !== 'constructor');
+      filter(key => key !== 'constructor' && key !== 'populate');
     const functions = Object.keys(Schema.Types.String.prototype).
       filter(key => ['constructor', 'cast', 'castForQuery', 'checkRequired'].indexOf(key) === -1);
     assert.deepEqual(keys.sort(), functions.sort());

From ffb420877a7acf51e12cba115ab3c275f7a79ff7 Mon Sep 17 00:00:00 2001
From: Vishal Gauba <vishal.gauba@gmail.com>
Date: Sun, 15 Nov 2020 17:04:03 +0530
Subject: [PATCH 1365/2348] fix(query): maxTimeMS in count, countDocuments,
 distinct

---
 lib/query.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/query.js b/lib/query.js
index d270efbf84b..6e679a3ee12 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2217,6 +2217,8 @@ Query.prototype._count = wrapThunk(function(callback) {
     return callback(this.error());
   }
 
+  applyGlobalMaxTimeMS(this.options, this.model);
+
   const conds = this._conditions;
   const options = this._optionsForExec();
 
@@ -2242,6 +2244,8 @@ Query.prototype._countDocuments = wrapThunk(function(callback) {
     return callback(this.error());
   }
 
+  applyGlobalMaxTimeMS(this.options, this.model);
+
   const conds = this._conditions;
   const options = this._optionsForExec();
 
@@ -2447,6 +2451,8 @@ Query.prototype.__distinct = wrapThunk(function __distinct(callback) {
     return null;
   }
 
+  applyGlobalMaxTimeMS(this.options, this.model);
+
   const options = this._optionsForExec();
 
   // don't pass in the conditions because we already merged them in

From 1b1ecbc8ddec3b21a5532b1592867e7318193a84 Mon Sep 17 00:00:00 2001
From: Vishal Gauba <vishal.gauba@gmail.com>
Date: Sun, 15 Nov 2020 17:23:29 +0530
Subject: [PATCH 1366/2348] fix(lint/es-next): move debug.test.js in es-next/
 to avoid lint error

---
 test/{ => es-next}/debug.test.js | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename test/{ => es-next}/debug.test.js (100%)

diff --git a/test/debug.test.js b/test/es-next/debug.test.js
similarity index 100%
rename from test/debug.test.js
rename to test/es-next/debug.test.js

From 16a42eff708a9687182465e0f2790ac118ff2e67 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Nov 2020 13:56:29 -0500
Subject: [PATCH 1367/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 7802f03e5d9..8b94c173cc0 100644
--- a/index.pug
+++ b/index.pug
@@ -166,6 +166,9 @@ html(lang='en')
 
           <div class="sponsors">
             <div>
+              <a rel="sponsored" href="https://localizejs.com/">
+                <img class="sponsor" src="https://images.opencollective.com/localize/bb2cd4d/logo/256.png" style="height: 100px">
+              </a>
               <a rel="sponsored" href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/payment-ninja-mongoose.png" style="height: 100px">
               </a>

From d1dce7947ce72d9b57a8c5e8c0136ef543bad00f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Nov 2020 16:58:00 -0500
Subject: [PATCH 1368/2348] test: repro #9549

---
 test/document.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index fe6ed0ea64f..077e16b7eb7 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -7876,6 +7876,28 @@ describe('document', function() {
         return doc.validate();
       });
     });
+
+    it('overwrites maps (gh-9549)', function() {
+      const schema = new Schema({
+        name: String,
+        myMap: { type: Map, of: String }
+      });
+      db.deleteModel(/Test/);
+      const Test = db.model('Test', schema);
+
+      let doc = new Test({ name: 'test', myMap: { a: 1, b: 2 } });
+
+      return co(function*() {
+        yield doc.save();
+
+        doc = yield Test.findById(doc);
+        doc.overwrite({ name: 'test2', myMap: { b: 2, c: 3 } });
+        yield doc.save();
+
+        doc = yield Test.findById(doc);
+        assert.deepEqual(Array.from(doc.toObject().myMap.values()), [2, 3]);
+      });
+    });
   });
 
   it('copies virtuals from array subdocs when casting array of docs with same schema (gh-7898)', function() {

From 6d72fafe12e27e3439478104f4eb6386f21f916c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 15 Nov 2020 16:58:23 -0500
Subject: [PATCH 1369/2348] fix: ensure `Document#overwrite()` correctly
 overwrites maps

Fix #9549
---
 lib/utils.js       |  5 +++++
 test/utils.test.js | 13 +++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/lib/utils.js b/lib/utils.js
index 48b29aa567c..02dda49c8a0 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -90,6 +90,11 @@ exports.deepEqual = function deepEqual(a, b) {
     return false;
   }
 
+  if (a instanceof Map && b instanceof Map) {
+    return deepEqual(Array.from(a.keys()), Array.from(b.keys())) &&
+      deepEqual(Array.from(a.values()), Array.from(b.values()));
+  }
+
   // Handle MongooseNumbers
   if (a instanceof Number && b instanceof Number) {
     return a.valueOf() === b.valueOf();
diff --git a/test/utils.test.js b/test/utils.test.js
index dd9059c8d29..2c9a83ebf53 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -168,6 +168,19 @@ describe('utils', function() {
     done();
   });
 
+  it('deepEquals on maps (gh-9549)', function() {
+    const a = new Map([['a', 1], ['b', 2]]);
+    let b = new Map([['a', 1], ['b', 2]]);
+
+    assert.ok(utils.deepEqual(a, b));
+
+    b = new Map([['a', 1]]);
+    assert.ok(!utils.deepEqual(a, b));
+
+    b = new Map([['b', 2], ['a', 1]]);
+    assert.ok(!utils.deepEqual(a, b));
+  });
+
   it('deepEquals on MongooseDocumentArray works', function(done) {
     const A = new Schema({ a: String });
     mongoose.deleteModel(/Test/);

From 7e20382a73feeaa3dcde2615e5e5bd62a7b1474d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Nov 2020 14:30:33 -0500
Subject: [PATCH 1370/2348] fix(model): automatically set
 `partialFilterExpression` for indexes in discriminator schemas

Fix #9542
Re: #6347
---
 lib/model.js               | 12 +++++-------
 test/model.indexes.test.js |  8 +++++++-
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 68c9649575d..76eba96ef7f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1682,18 +1682,16 @@ function _decorateDiscriminatorIndexOptions(model, indexOptions) {
   // If the model is a discriminator and it has a unique index, add a
   // partialFilterExpression by default so the unique index will only apply
   // to that discriminator.
-  if (model.baseModelName != null && indexOptions.unique &&
-      !('partialFilterExpression' in indexOptions) &&
-      !('sparse' in indexOptions)) {
-
+  if (model.baseModelName != null &&
+    !('partialFilterExpression' in indexOptions) &&
+    !('sparse' in indexOptions)) {
     const value = (
       model.schema.discriminatorMapping &&
       model.schema.discriminatorMapping.value
     ) || model.modelName;
+    const discriminatorKey = model.schema.options.discriminatorKey;
 
-    indexOptions.partialFilterExpression = {
-      [model.schema.options.discriminatorKey]: value
-    };
+    indexOptions.partialFilterExpression = { [discriminatorKey]: value };
   }
   return indexOptions;
 }
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 9e6b63012ea..107aabe52ed 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -513,6 +513,7 @@ describe('model', function() {
       const deviceSchema = new Schema({
         _id: { type: Schema.ObjectId, auto: true },
         name: { type: String, unique: true }, // Should become a partial
+        other: { type: String, index: true }, // Should become a partial
         model: { type: String }
       });
 
@@ -525,7 +526,12 @@ describe('model', function() {
         Base.create({}),
         User.create({ emailId: 'val@karpov.io', firstName: 'Val' }),
         Device.create({ name: 'Samsung', model: 'Galaxy' })
-      ]);
+      ]).then(() => Base.listIndexes()).
+        then(indexes => indexes.find(i => i.key.other)).
+        then(index => {
+          assert.deepEqual(index.key, { other: 1 });
+          assert.deepEqual(index.partialFilterExpression, { kind: 'Device' });
+        });
     });
 
     it('decorated discriminator index with syncIndexes (gh-6347)', function() {

From 99da46357a4d040f6a8b310bf0297167e1c6dc47 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Nov 2020 16:42:15 -0500
Subject: [PATCH 1371/2348] chore: release 5.10.15

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 8999e984490..fd55f2c6afc 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.10.15 / 2020-11-16
+====================
+ * fix(array): make sure `Array#toObject()` returns a vanilla JavaScript array in Node.js 6+ #9540
+ * fix(connection): make `disconnect()` stop Mongoose if it is trying to reconnect #9531
+ * fix: ensure `Document#overwrite()` correctly overwrites maps #9549
+ * fix(document): make transform work with nested paths #9544 #9543 [jonathan-wilkinson](https://github.com/jonathan-wilkinson)
+ * fix(query): maxTimeMS in count, countDocuments, distinct #9552 [FlameFractal](https://github.com/FlameFractal)
+ * fix(schema): remove warning re: `increment` as a schema path name #9538
+ * fix(model): automatically set `partialFilterExpression` for indexes in discriminator schemas #9542
+
 5.10.14 / 2020-11-12
 ====================
  * fix(update): handle casting immutable object properties with `$setOnInsert` #9537
diff --git a/package.json b/package.json
index 522357f420d..cbd6ff3e704 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.14",
+  "version": "5.10.15",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From e6bab316d19e450d59e68a18ad9bbe272fc7f520 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Nov 2020 17:45:27 -0500
Subject: [PATCH 1372/2348] chore(index.d.ts): exclude methods defined in
 interface from lean documents

Address some feedback from @taxilian

Re: #8108
---
 index.d.ts                       | 5 ++++-
 test/typescript/leanDocuments.ts | 7 +++++++
 test/typescript/main.test.js     | 3 ++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 0593c30015d..3184e817904 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1704,7 +1704,10 @@ declare module "mongoose" {
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;
 
-  export type LeanDocument<T> = Omit<T, Exclude<keyof Document, '_id'>>;
+  type FunctionPropertyNames<T> = { 
+    [K in keyof T]: T[K] extends Function ? K : never 
+  }[keyof T];
+  export type LeanDocument<T> = Omit<Omit<T, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
 
   class QueryCursor<DocType extends Document> extends stream.Readable {
     /**
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 0f72217e1a9..6c6dd5b2859 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -5,19 +5,26 @@ const schema: Schema = new Schema({ name: { type: 'String' } });
 interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
+  testMethod: () => number;
 }
 
+schema.method('testMethod', () => 42);
+
 const Test = model<ITest>('Test', schema);
 
 void async function main() {
   const doc: ITest = await Test.findOne();
 
+  doc.testMethod();
+
   const pojo = doc.toObject();
   await pojo.save();
 
   const _doc = await Test.findOne().lean();
   await _doc.save();
 
+  _doc.testMethod();
+
   const hydrated = Test.hydrate(_doc);
   await hydrated.save();
 }();
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index b9bb974f77a..d78d07eefb6 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -125,9 +125,10 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 2);
+    assert.equal(errors.length, 3);
     assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
     assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
+    assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[0].messageText);
   });
 });
 

From 7cd455d1829d0052abf6a54a30512391d23cddc4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 16 Nov 2020 19:02:24 -0500
Subject: [PATCH 1373/2348] chore: update opencollective sponsors

---
 index.pug | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/index.pug b/index.pug
index 8b94c173cc0..4fd8986012d 100644
--- a/index.pug
+++ b/index.pug
@@ -367,6 +367,15 @@ html(lang='en')
               <a rel="sponsored" href="https://masonslots.com/">
                 <img class="sponsor" src="https://images.opencollective.com/masonslots/29251dd/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://twojtyp.pl/">
+                <img class="sponsor" src="https://images.opencollective.com/twojtyp/cd0b486/logo/256.png" style="height: 100px">
+              </a>
+              <a rel="sponsored" href="https://nettikasinot247.fi/">
+                <img class="sponsor" src="https://images.opencollective.com/nettikasinot-24-7/c51fe6a/logo/256.png" style="height: 100px">
+              </a>
+              <a rel="sponsored" href="https://www.kasinosivu.com/pikakasinot/">
+                <img class="sponsor" src="https://images.opencollective.com/pikakasinot/5ef0793/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 293c353bbaf082f8ced0836d1295bfe17682ecc4 Mon Sep 17 00:00:00 2001
From: Christophe Querton <kertof@users.noreply.github.com>
Date: Tue, 17 Nov 2020 10:30:38 +0100
Subject: [PATCH 1374/2348] Update dates.md

---
 docs/tutorials/dates.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/tutorials/dates.md b/docs/tutorials/dates.md
index a4181100f6d..582ed41ba6c 100644
--- a/docs/tutorials/dates.md
+++ b/docs/tutorials/dates.md
@@ -70,11 +70,11 @@ new Date('2010'); // 2010-01-01T00:00:00.000Z
 Mongoose converts numeric strings that contain numbers outside the [range of representable dates in JavaScript](https://stackoverflow.com/questions/11526504/minimum-and-maximum-date) and converts them to numbers before passing them to the date constructor.
 
 ```javascript
-require: Date Tutorial.*Example 1.4.3]
+[require: Date Tutorial.*Example 1.4.3]
 ```
 
 ## Timezones
 
 [MongoDB stores dates as 64-bit integers](http://bsonspec.org/spec.html), which
 means that Mongoose does **not** store timezone information by default. When
-you call `Date#toString()`, the JavaScript runtime will use [your OS' timezone](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTimezoneOffset).
\ No newline at end of file
+you call `Date#toString()`, the JavaScript runtime will use [your OS' timezone](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTimezoneOffset).

From 16be7cb6d8a10cb250620f14c905f1a7abcfd485 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Nov 2020 13:56:38 -0500
Subject: [PATCH 1375/2348] chore(index.d.ts): pull `any` types into
 LeanDocuments correctly

Re: #8108
---
 index.d.ts                       | 5 +++--
 test/typescript/leanDocuments.ts | 3 +++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3184e817904..977c28a4452 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1704,8 +1704,9 @@ declare module "mongoose" {
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;
 
-  type FunctionPropertyNames<T> = { 
-    [K in keyof T]: T[K] extends Function ? K : never 
+  type FunctionPropertyNames<T> = {
+    // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
+    [K in keyof T]: 0 extends (1 & T[K]) ? never : (T[K] extends Function ? K : never) 
   }[keyof T];
   export type LeanDocument<T> = Omit<Omit<T, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
 
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 6c6dd5b2859..a05775138ab 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -5,6 +5,7 @@ const schema: Schema = new Schema({ name: { type: 'String' } });
 interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
+  mixed?: any;
   testMethod: () => number;
 }
 
@@ -24,6 +25,8 @@ void async function main() {
   await _doc.save();
 
   _doc.testMethod();
+  _doc.name = 'test';
+  _doc.mixed = 42;
 
   const hydrated = Test.hydrate(_doc);
   await hydrated.save();

From 092144c879c40f874bb1555ec625274e2b1e1a14 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Nov 2020 14:22:13 -0500
Subject: [PATCH 1376/2348] chore(index.d.ts): add ability to create doc arrays
 for easier setting

Re: #8108
---
 index.d.ts                       |  3 +++
 test/types.documentarray.test.js | 18 ++++++++++++++++++
 test/typescript/docArray.ts      | 25 +++++++++++++++++++++++++
 test/typescript/main.test.js     |  8 ++++++++
 4 files changed, 54 insertions(+)
 create mode 100644 test/typescript/docArray.ts

diff --git a/index.d.ts b/index.d.ts
index 977c28a4452..b937810d84b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1268,6 +1268,9 @@ declare module "mongoose" {
     class Decimal128 extends mongodb.Decimal128 { }
 
     class DocumentArray<T extends Document> extends Types.Array<T> {
+      /** DocumentArray constructor */
+      constructor(values: any[]);
+
       isMongooseDocumentArray: true;
 
       /** Creates a subdocument casted to this schema. */
diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 93bafeccaa8..22de14b7323 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -689,4 +689,22 @@ describe('types.documentarray', function() {
     assert.equal(doc2.subDocArray[0].ownerDocument().name, 'doc2');
     assert.equal(doc1.subDocArray[0].ownerDocument().name, 'doc1');
   });
+
+  it('supports setting to newly constructed array with no path or parent (gh-8108)', function() {
+    const nestedArraySchema = Schema({
+      name: String,
+      subDocArray: [{ _id: false, name: String }]
+    });
+
+    const Model = db.model('Test', nestedArraySchema);
+
+    const doc = new Model({ name: 'doc1' });
+    doc.subDocArray = new DocumentArray([]);
+
+    doc.subDocArray.push({ name: 'foo' });
+
+    return doc.save().
+      then(() => Model.findById(doc)).
+      then(doc => assert.deepEqual(doc.toObject().subDocArray, [{ name: 'foo' }]));
+  });
 });
diff --git a/test/typescript/docArray.ts b/test/typescript/docArray.ts
new file mode 100644
index 00000000000..081e6153cc8
--- /dev/null
+++ b/test/typescript/docArray.ts
@@ -0,0 +1,25 @@
+import { Schema, model, Document, Types } from 'mongoose';
+
+const schema: Schema = new Schema({ tags: [new Schema({ name: String })] });
+
+interface Subdoc extends Document {
+  name: string
+}
+
+interface ITest extends Document {
+  tags: Types.DocumentArray<Subdoc>
+}
+
+const Test = model<ITest>('Test', schema);
+
+void async function main() {
+  const doc: ITest = await Test.findOne();
+
+  doc.tags = new Types.DocumentArray<Subdoc>([]);
+  doc.set('tags', []);
+
+  const record: Subdoc = doc.tags.create({ name: 'test' });
+  doc.tags.push(record);
+
+  await doc.save();
+}();
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index d78d07eefb6..fbda71ca14c 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -130,6 +130,14 @@ describe('typescript syntax', function() {
     assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
     assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[0].messageText);
   });
+
+  it('doc array', function() {
+    const errors = runTest('docArray.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {

From cb0bd0b296935ac51c18dba036b17ab38b24298d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Nov 2020 15:01:19 -0500
Subject: [PATCH 1377/2348] chore(index.d.ts): add recursive lean document
 support

Re: #8108
---
 index.d.ts                       | 21 ++++++++++++++++++++-
 test/typescript/docArray.ts      |  6 +++++-
 test/typescript/leanDocuments.ts |  8 ++++++++
 test/typescript/main.test.js     | 10 ++++++----
 4 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b937810d84b..74f2b5e4bdd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1711,7 +1711,26 @@ declare module "mongoose" {
     // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
     [K in keyof T]: 0 extends (1 & T[K]) ? never : (T[K] extends Function ? K : never) 
   }[keyof T];
-  export type LeanDocument<T> = Omit<Omit<T, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
+
+  type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
+  type TreatAsPrimitives = actualPrimitives |
+    Date | RegExp | Symbol | Error | BigInt | Types.ObjectId;
+
+  type LeanType<T> =
+    0 extends (1 & T) ? T : // any
+    T extends TreatAsPrimitives ? T : // primitives
+    [T] extends [Document] ? LeanDocument<T> :
+    T;
+
+  export type _LeanDocument<T> = {
+    [K in keyof T]:
+      0 extends (1 & T[K]) ? T[K] : // any
+      T[K] extends unknown[] ? LeanType<T[K][number]>[] : // Array
+      T[K] extends Document ? LeanDocument<T[K]> : // Subdocument
+      T[K];
+  };
+
+  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
 
   class QueryCursor<DocType extends Document> extends stream.Readable {
     /**
diff --git a/test/typescript/docArray.ts b/test/typescript/docArray.ts
index 081e6153cc8..c7911e17c29 100644
--- a/test/typescript/docArray.ts
+++ b/test/typescript/docArray.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document, Types } from 'mongoose';
+import { Schema, model, Document, Types, LeanDocument } from 'mongoose';
 
 const schema: Schema = new Schema({ tags: [new Schema({ name: String })] });
 
@@ -22,4 +22,8 @@ void async function main() {
   doc.tags.push(record);
 
   await doc.save();
+
+  const _doc: LeanDocument<ITest> = await Test.findOne().lean();
+  _doc.tags[0].name.substr(1);
+  _doc.tags.create({ name: 'fail' });
 }();
\ No newline at end of file
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index a05775138ab..c8b260141d0 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -2,10 +2,15 @@ import { Schema, model, Document, Types } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
+class Subdoc extends Document {
+  name: string
+}
+
 interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
   mixed?: any;
+  subdoc?: Subdoc;
   testMethod: () => number;
 }
 
@@ -16,6 +21,8 @@ const Test = model<ITest>('Test', schema);
 void async function main() {
   const doc: ITest = await Test.findOne();
 
+  doc.subdoc = new Subdoc({ name: 'test' });
+
   doc.testMethod();
 
   const pojo = doc.toObject();
@@ -25,6 +32,7 @@ void async function main() {
   await _doc.save();
 
   _doc.testMethod();
+  _doc.subdoc.toObject();
   _doc.name = 'test';
   _doc.mixed = 42;
 
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index fbda71ca14c..244e961d7c0 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -125,10 +125,11 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 3);
+    assert.equal(errors.length, 4);
     assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
-    assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
-    assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[0].messageText);
+    assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[1].messageText);
+    assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[2].messageText);
+    assert.ok(errors[3].messageText.includes('Property \'toObject\' does not exist'), errors[3].messageText);
   });
 
   it('doc array', function() {
@@ -136,7 +137,8 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 0);
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.includes('Property \'create\' does not exist'), errors[0].messageText);
   });
 });
 

From 6635bf8ca43b00795a6b425afd15f1fdf250c17e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Nov 2020 17:03:04 -0500
Subject: [PATCH 1378/2348] chore(index.d.ts): support push and unshift
 arbitrary values

Re: #8108
---
 index.d.ts                       | 6 ++++++
 test/typescript/docArray.ts      | 2 ++
 test/typescript/leanDocuments.ts | 1 +
 3 files changed, 9 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 74f2b5e4bdd..e9488c0ae2b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1235,6 +1235,9 @@ declare module "mongoose" {
       /** Pushes items to the array non-atomically. */
       nonAtomicPush(...args: any[]): number;
 
+      /** Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking. */
+      push(...args: any[]): number;
+
       /**
        * Pulls items from the array atomically. Equality is determined by casting
        * the provided value to an embedded document and comparing using
@@ -1255,6 +1258,9 @@ declare module "mongoose" {
 
       /** Returns a native js Array. */
       toObject(options: ToObjectOptions): any;
+
+      /** Wraps [`Array#unshift`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/unshift) with proper change tracking. */
+      unshift(...args: any[]): number;
     }
 
     class Buffer extends global.Buffer {
diff --git a/test/typescript/docArray.ts b/test/typescript/docArray.ts
index c7911e17c29..24d31ee7434 100644
--- a/test/typescript/docArray.ts
+++ b/test/typescript/docArray.ts
@@ -21,6 +21,8 @@ void async function main() {
   const record: Subdoc = doc.tags.create({ name: 'test' });
   doc.tags.push(record);
 
+  doc.tags.push({ name: 'test' });
+
   await doc.save();
 
   const _doc: LeanDocument<ITest> = await Test.findOne().lean();
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index c8b260141d0..0646a046fd2 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -22,6 +22,7 @@ void async function main() {
   const doc: ITest = await Test.findOne();
 
   doc.subdoc = new Subdoc({ name: 'test' });
+  doc.id = 'Hello';
 
   doc.testMethod();
 

From 7447e86329bc69b4966af193a737acc761fa5269 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Nov 2020 17:32:27 -0500
Subject: [PATCH 1379/2348] chore(index.d.ts): clean up implicit any and remove
 methods for doc arrays that don't extend Document

Re: #8108
---
 index.d.ts                       | 49 ++++++++++++++++----------------
 test/typescript/leanDocuments.ts |  2 +-
 2 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e9488c0ae2b..47176bebfe1 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -92,7 +92,7 @@ declare module "mongoose" {
   export function now(): Date;
 
   /** Declares a global plugin executed on all Schemas. */
-  export function plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
+  export function plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): typeof mongoose;
 
   /** Getter/setter around function for pluralizing collection names. */
   export function pluralize(fn?: (str: string) => string): (str: string) => string;
@@ -226,7 +226,7 @@ declare module "mongoose" {
     port: number;
 
     /** Declares a plugin executed on all schemas you pass to `conn.model()` */
-    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
+    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): Connection;
 
     /** The plugins that will be applied to all models created on this connection. */
     plugins: Array<any>;
@@ -265,7 +265,7 @@ declare module "mongoose" {
      * async function executes successfully and attempt to retry if
      * there was a retriable error.
      */
-    transaction(fn: (session: mongodb.ClientSession) => Promise<any>);
+    transaction(fn: (session: mongodb.ClientSession) => Promise<any>): Promise<any>;
 
     /** Switches to a different database using the same connection pool. */
     useDb(name: string, options?: { useCache?: boolean }): Connection;
@@ -283,23 +283,23 @@ declare module "mongoose" {
     constructor(doc?: any);
 
     /** Don't run validation on this path or persist changes to this path. */
-    $ignore(path: string);
+    $ignore(path: string): void;
 
     /** Checks if a path is set to its default. */
-    $isDefault(path: string);
+    $isDefault(path: string): boolean;
 
     /** Getter/setter, determines whether the document was removed or not. */
-    $isDeleted(val?: boolean);
+    $isDeleted(val?: boolean): boolean;
 
     /**
      * Returns true if the given path is nullish or only contains empty objects.
      * Useful for determining whether this subdoc will get stripped out by the
      * [minimize option](/docs/guide.html#minimize).
      */
-    $isEmpty(path: string);
+    $isEmpty(path: string): boolean;
 
     /** Checks if a path is invalid */
-    $isValid(path: string);
+    $isValid(path: string): boolean;
 
     /**
      * Empty object that you can use for storing properties on the document. This
@@ -309,7 +309,7 @@ declare module "mongoose" {
     $locals: object;
 
     /** Marks a path as valid, removing existing validation errors. */
-    $markValid(path: string);
+    $markValid(path: string): void;
 
     /**
      * A string containing the current operation that Mongoose is executing
@@ -376,7 +376,7 @@ declare module "mongoose" {
     execPopulate(callback: (err: CallbackError, res: this) => void): void;
 
     /** Returns the value of a path. */
-    get(path: string, type?: any, options?: any);
+    get(path: string, type?: any, options?: any): any;
 
     /**
      * Returns the changes that happened to the document
@@ -407,7 +407,7 @@ declare module "mongoose" {
     isDirectSelected(path: string): boolean;
 
     /** Checks if `path` is in the `init` state, that is, it was set by `Document#init()` and not modified since. */
-    isInit(path: string);
+    isInit(path: string): boolean;
 
     /**
      * Returns true if any of the given paths is modified, else false. If no arguments, returns `true` if any path
@@ -422,7 +422,7 @@ declare module "mongoose" {
     isNew: boolean;
 
     /** Marks the path as having pending changes to write to the db. */
-    markModified(path: string, scope?: any);
+    markModified(path: string, scope?: any): void;
 
     /** Returns the list of paths that have been modified. */
     modifiedPaths(options?: { includeChildren?: boolean }): Array<string>;
@@ -478,7 +478,7 @@ declare module "mongoose" {
     toObject(options?: ToObjectOptions): LeanDocument<this>;
 
     /** Clears the modified state on the specified path. */
-    unmarkModified(path: string);
+    unmarkModified(path: string): void;
 
     /** Sends an update command with this document `_id` as the query selector. */
     update(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
@@ -901,7 +901,7 @@ declare module "mongoose" {
     pathType(path: string): string;
 
     /** Registers a plugin for this schema. */
-    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any);
+    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
     post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
@@ -1095,13 +1095,13 @@ declare module "mongoose" {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator(name: string, schema: Schema, tag?: string);
+        discriminator(name: string, schema: Schema, tag?: string): any;
 
         /**
          * Adds an enum validator if this is an array of strings or numbers. Equivalent to
          * `SchemaString.prototype.enum()` or `SchemaNumber.prototype.enum()`
          */
-        enum(vals: string[] | number[]);
+        enum(vals: string[] | number[]): this;
       }
 
       class Boolean extends SchemaType {
@@ -1151,7 +1151,7 @@ declare module "mongoose" {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator(name: string, schema: Schema, tag?: string);
+        discriminator(name: string, schema: Schema, tag?: string): any;
       }
 
       class Map extends SchemaType {
@@ -1169,7 +1169,7 @@ declare module "mongoose" {
         static schemaName: string;
 
         /** Sets a enum validator */
-        enum(vals: number[]);
+        enum(vals: number[]): this;
 
         /** Sets a maximum number validator. */
         max(value: number, message: string): this;
@@ -1537,7 +1537,7 @@ declare module "mongoose" {
 
     /** Specifies a `$ne` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     ne(val: any): this;
-    ne(path: string, val: any);
+    ne(path: string, val: any): this;
 
     /** Specifies a `$near` or `$nearSphere` condition */
     near(val: any): this;
@@ -1725,8 +1725,7 @@ declare module "mongoose" {
   type LeanType<T> =
     0 extends (1 & T) ? T : // any
     T extends TreatAsPrimitives ? T : // primitives
-    [T] extends [Document] ? LeanDocument<T> :
-    T;
+    LeanDocument<T>; // Documents and everything else
 
   export type _LeanDocument<T> = {
     [K in keyof T]:
@@ -1743,7 +1742,7 @@ declare module "mongoose" {
      * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
      * Useful for setting the `noCursorTimeout` and `tailable` flags.
      */
-    addCursorFlag(flag: string, value: boolean);
+    addCursorFlag(flag: string, value: boolean): this;
 
     /**
      * Marks this cursor as closed. Will stop streaming and subsequent calls to
@@ -1866,7 +1865,7 @@ declare module "mongoose" {
      * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
      * Useful for setting the `noCursorTimeout` and `tailable` flags.
      */
-    addCursorFlag(flag: string, value: boolean);
+    addCursorFlag(flag: string, value: boolean): this;
 
     /**
      * Marks this cursor as closed. Will stop streaming and subsequent calls to
@@ -1904,7 +1903,7 @@ declare module "mongoose" {
     /** Get/set the function used to cast arbitrary values to this type. */
     static cast(caster?: Function | boolean): Function;
 
-    static checkRequired(checkRequired: (v: any) => boolean);
+    static checkRequired(checkRequired?: (v: any) => boolean): (v: any) => boolean;
 
     /** Sets a default option for this schema type. */
     static set(option: string, value: any): void;
@@ -1955,7 +1954,7 @@ declare module "mongoose" {
     text(bool: boolean): this;
 
     /** Defines a custom function for transforming this path when converting a document to JSON. */
-    transform(fn: (value: any) => any);
+    transform(fn: (value: any) => any): this;
 
     /** Declares an unique index. */
     unique(bool: boolean): this;
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 0646a046fd2..d86b9499ad9 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -3,7 +3,7 @@ import { Schema, model, Document, Types } from 'mongoose';
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 class Subdoc extends Document {
-  name: string
+  name: string;
 }
 
 interface ITest extends Document {

From ba2b75363bfd8fba080478f79a5f841e2a58f4a7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 18 Nov 2020 21:12:55 -0500
Subject: [PATCH 1380/2348] refactor(document): replace `handleIndex()` with a
 simple for loop and clean up some unnecessary ifs

Fix #9563
---
 lib/document.js | 166 +++++++++++++++++++++++-------------------------
 1 file changed, 80 insertions(+), 86 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d8c49ce4705..4f204032d0c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -925,7 +925,11 @@ Document.prototype.$set = function $set(path, val, type, options) {
     adhocs[path] = this.schema.interpretAsType(path, type, this.schema.options);
   }
 
-  if (typeof path !== 'string') {
+  if (path == null) {
+    const _ = path;
+    path = val;
+    val = _;
+  } else if (typeof path !== 'string') {
     // new Document({ key: val })
     if (path instanceof Document) {
       if (path.$__isNested) {
@@ -935,101 +939,91 @@ Document.prototype.$set = function $set(path, val, type, options) {
       }
     }
 
-    if (path == null) {
-      const _ = path;
-      path = val;
-      val = _;
-    } else {
-      prefix = val ? val + '.' : '';
-
-      keys = Object.keys(path);
-      const len = keys.length;
-
-      // `_skipMinimizeTopLevel` is because we may have deleted the top-level
-      // nested key to ensure key order.
-      const _skipMinimizeTopLevel = get(options, '_skipMinimizeTopLevel', false);
-      if (len === 0 && _skipMinimizeTopLevel) {
-        delete options._skipMinimizeTopLevel;
-        if (val) {
-          this.$set(val, {});
-        }
-        return this;
-      }
+    prefix = val ? val + '.' : '';
 
-      while (i < len) {
-        _handleIndex.call(this, i++);
-      }
+    keys = Object.keys(path);
+    const len = keys.length;
 
+    // `_skipMinimizeTopLevel` is because we may have deleted the top-level
+    // nested key to ensure key order.
+    const _skipMinimizeTopLevel = get(options, '_skipMinimizeTopLevel', false);
+    if (len === 0 && _skipMinimizeTopLevel) {
+      delete options._skipMinimizeTopLevel;
+      if (val) {
+        this.$set(val, {});
+      }
       return this;
     }
-  } else {
-    this.$__.$setCalled.add(path);
-  }
-
-  function _handleIndex(i) {
-    key = keys[i];
-    const pathName = prefix + key;
-    pathtype = this.schema.pathType(pathName);
-
-    // On initial set, delete any nested keys if we're going to overwrite
-    // them to ensure we keep the user's key order.
-    if (type === true &&
-        !prefix &&
-        path[key] != null &&
-        pathtype === 'nested' &&
-        this._doc[key] != null &&
-        Object.keys(this._doc[key]).length === 0) {
-      delete this._doc[key];
-      // Make sure we set `{}` back even if we minimize re: gh-8565
-      options = Object.assign({}, options, { _skipMinimizeTopLevel: true });
-    }
-
-    if (typeof path[key] === 'object' &&
-        !utils.isNativeObject(path[key]) &&
-        !utils.isMongooseType(path[key]) &&
-        path[key] != null &&
-        pathtype !== 'virtual' &&
-        pathtype !== 'real' &&
-        pathtype !== 'adhocOrUndefined' &&
-        !(this.$__path(pathName) instanceof MixedSchema) &&
-        !(this.schema.paths[pathName] &&
-        this.schema.paths[pathName].options &&
-        this.schema.paths[pathName].options.ref)) {
-      this.$__.$setCalled.add(prefix + key);
-      this.$set(path[key], prefix + key, constructing, options);
-    } else if (strict) {
-      // Don't overwrite defaults with undefined keys (gh-3981) (gh-9039)
-      if (constructing && path[key] === void 0 &&
-          this.get(pathName) !== void 0) {
-        return;
-      }
 
-      if (pathtype === 'adhocOrUndefined') {
-        pathtype = getEmbeddedDiscriminatorPath(this, pathName, { typeOnly: true });
-      }
+    for (let i = 0; i < len; ++i) {
+      key = keys[i];
+      const pathName = prefix + key;
+      pathtype = this.schema.pathType(pathName);
+
+      // On initial set, delete any nested keys if we're going to overwrite
+      // them to ensure we keep the user's key order.
+      if (type === true &&
+          !prefix &&
+          path[key] != null &&
+          pathtype === 'nested' &&
+          this._doc[key] != null &&
+          Object.keys(this._doc[key]).length === 0) {
+        delete this._doc[key];
+        // Make sure we set `{}` back even if we minimize re: gh-8565
+        options = Object.assign({}, options, { _skipMinimizeTopLevel: true });
+      }
+
+      if (typeof path[key] === 'object' &&
+          !utils.isNativeObject(path[key]) &&
+          !utils.isMongooseType(path[key]) &&
+          path[key] != null &&
+          pathtype !== 'virtual' &&
+          pathtype !== 'real' &&
+          pathtype !== 'adhocOrUndefined' &&
+          !(this.$__path(pathName) instanceof MixedSchema) &&
+          !(this.schema.paths[pathName] &&
+          this.schema.paths[pathName].options &&
+          this.schema.paths[pathName].options.ref)) {
+        this.$__.$setCalled.add(prefix + key);
+        this.$set(path[key], prefix + key, constructing, options);
+      } else if (strict) {
+        // Don't overwrite defaults with undefined keys (gh-3981) (gh-9039)
+        if (constructing && path[key] === void 0 &&
+            this.get(pathName) !== void 0) {
+          return this;
+        }
 
-      if (pathtype === 'real' || pathtype === 'virtual') {
-        // Check for setting single embedded schema to document (gh-3535)
-        let p = path[key];
-        if (this.schema.paths[pathName] &&
-            this.schema.paths[pathName].$isSingleNested &&
-            path[key] instanceof Document) {
-          p = p.toObject({ virtuals: false, transform: false });
+        if (pathtype === 'adhocOrUndefined') {
+          pathtype = getEmbeddedDiscriminatorPath(this, pathName, { typeOnly: true });
         }
-        this.$set(prefix + key, p, constructing, options);
-      } else if (pathtype === 'nested' && path[key] instanceof Document) {
-        this.$set(prefix + key,
-          path[key].toObject({ transform: false }), constructing, options);
-      } else if (strict === 'throw') {
-        if (pathtype === 'nested') {
-          throw new ObjectExpectedError(key, path[key]);
-        } else {
-          throw new StrictModeError(key);
+
+        if (pathtype === 'real' || pathtype === 'virtual') {
+          // Check for setting single embedded schema to document (gh-3535)
+          let p = path[key];
+          if (this.schema.paths[pathName] &&
+              this.schema.paths[pathName].$isSingleNested &&
+              path[key] instanceof Document) {
+            p = p.toObject({ virtuals: false, transform: false });
+          }
+          this.$set(prefix + key, p, constructing, options);
+        } else if (pathtype === 'nested' && path[key] instanceof Document) {
+          this.$set(prefix + key,
+            path[key].toObject({ transform: false }), constructing, options);
+        } else if (strict === 'throw') {
+          if (pathtype === 'nested') {
+            throw new ObjectExpectedError(key, path[key]);
+          } else {
+            throw new StrictModeError(key);
+          }
         }
+      } else if (path[key] !== void 0) {
+        this.$set(prefix + key, path[key], constructing, options);
       }
-    } else if (path[key] !== void 0) {
-      this.$set(prefix + key, path[key], constructing, options);
     }
+
+    return this;
+  } else {
+    this.$__.$setCalled.add(path);
   }
 
   let pathType = this.schema.pathType(path);

From 9fd31f997587dff183e934620dfa0d4f689ab2af Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 19 Nov 2020 16:02:58 -0500
Subject: [PATCH 1381/2348] docs(virtualtype): work around tj/dox#60

Fix #9568
---
 lib/virtualtype.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/virtualtype.js b/lib/virtualtype.js
index 35f26b45e7b..20ba71a02dd 100644
--- a/lib/virtualtype.js
+++ b/lib/virtualtype.js
@@ -69,7 +69,7 @@ VirtualType.prototype.clone = function() {
 /**
  * Adds a custom getter to this virtual.
  *
- * Mongoose calls the getter function with 3 parameters:
+ * Mongoose calls the getter function with the below 3 parameters.
  *
  * - `value`: the value returned by the previous getter. If there is only one getter, `value` will be `undefined`.
  * - `virtual`: the virtual object you called `.get()` on
@@ -95,7 +95,7 @@ VirtualType.prototype.get = function(fn) {
 /**
  * Adds a custom setter to this virtual.
  *
- * Mongoose calls the setter function with 3 parameters:
+ * Mongoose calls the setter function with the below 3 parameters.
  *
  * - `value`: the value being set
  * - `virtual`: the virtual object you're calling `.set()` on

From d6e48a4f40ca56f55468683263a64bc93a199432 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Nov 2020 12:41:31 -0500
Subject: [PATCH 1382/2348] test(schema): repro #9564

---
 test/schema.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 33a86dcfea3..82ee9534ba3 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2506,4 +2506,16 @@ describe('schema', function() {
     const casted = schema.path('ids').cast([[]]);
     assert.equal(casted[0].$path(), 'ids.$');
   });
+
+  it('supports `of` for array type definition (gh-9564)', function() {
+    const schema = new Schema({
+      nums: { type: Array, of: Number },
+      tags: { type: 'array', of: String },
+      subdocs: { type: Array, of: Schema({ name: String }) }
+    });
+
+    assert.equal(schema.path('nums').caster.instance, 'Number');
+    assert.equal(schema.path('tags').caster.instance, 'String');
+    assert.equal(schema.path('subdocs').casterConstructor.schema.path('name').instance, 'String');
+  });
 });

From 63a07b62d7849d23de4da6d6a6a061207d490047 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Nov 2020 12:41:46 -0500
Subject: [PATCH 1383/2348] fix(schema): support `of` for array type
 definitions to be consistent with maps

Fix #9564
---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index db021696d57..68078ea659d 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -902,7 +902,7 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
   if (Array.isArray(type) || type === Array || type === 'array' || type === MongooseTypes.Array) {
     // if it was specified through { type } look for `cast`
     let cast = (type === Array || type === 'array')
-      ? obj.cast
+      ? obj.cast || obj.of
       : type[0];
 
     if (cast && cast.instanceOfSchema) {

From 3a867422ac365c149f346024ff9103335eb96d7f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Nov 2020 12:44:30 -0500
Subject: [PATCH 1384/2348] chore: add `of` to schema array options

Re: #9564
---
 lib/options/SchemaArrayOptions.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/lib/options/SchemaArrayOptions.js b/lib/options/SchemaArrayOptions.js
index ddd0b37a935..87544944713 100644
--- a/lib/options/SchemaArrayOptions.js
+++ b/lib/options/SchemaArrayOptions.js
@@ -32,6 +32,26 @@ const opts = require('./propertyOptions');
 
 Object.defineProperty(SchemaArrayOptions.prototype, 'enum', opts);
 
+/**
+ * If set, specifies the type of this array's values. Equivalent to setting
+ * `type` to an array whose first element is `of`.
+ *
+ * ####Example:
+ *
+ *     // `arr` is an array of numbers.
+ *     new Schema({ arr: [Number] });
+ *     // Equivalent way to define `arr` as an array of numbers
+ *     new Schema({ arr: { type: Array, of: Number } });
+ *
+ * @api public
+ * @property of
+ * @memberOf SchemaArrayOptions
+ * @type Function|String
+ * @instance
+ */
+
+Object.defineProperty(SchemaArrayOptions.prototype, 'enum', opts);
+
 /*!
  * ignore
  */

From 9b0a0e41275f4945b8f4bb643c2df4606b015d00 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Nov 2020 17:00:21 -0500
Subject: [PATCH 1385/2348] perf(utils): major speedup for `deepEqual()` on
 documents and arrays

Re: #9396
---
 lib/utils.js | 40 +++++++++++++++++++++++++---------------
 1 file changed, 25 insertions(+), 15 deletions(-)

diff --git a/lib/utils.js b/lib/utils.js
index 02dda49c8a0..cdf8e676172 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -62,6 +62,10 @@ exports.deepEqual = function deepEqual(a, b) {
     return true;
   }
 
+  if (typeof a !== 'object' && typeof b !== 'object') {
+    return a === b;
+  }
+
   if (a instanceof Date && b instanceof Date) {
     return a.getTime() === b.getTime();
   }
@@ -78,10 +82,6 @@ exports.deepEqual = function deepEqual(a, b) {
         a.global === b.global;
   }
 
-  if (typeof a !== 'object' && typeof b !== 'object') {
-    return a === b;
-  }
-
   if (a === null || b === null || a === undefined || b === undefined) {
     return false;
   }
@@ -104,24 +104,34 @@ exports.deepEqual = function deepEqual(a, b) {
     return exports.buffer.areEqual(a, b);
   }
 
-  if (isMongooseObject(a)) {
+  if (Array.isArray(a) && Array.isArray(b)) {
+    if (a.length !== b.length) {
+      return false;
+    }
+    const len = a.length;
+    for (let i = 0; i < len; ++i) {
+      if (!deepEqual(a[i], b[i])) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  if (a.$__ != null) {
+    a = a._doc;
+  } else if (isMongooseObject(a)) {
     a = a.toObject();
   }
-  if (isMongooseObject(b)) {
+  if (b.$__ != null) {
+    b = b._doc;
+  } else if (isMongooseObject(b)) {
     b = b.toObject();
   }
 
-  let ka;
-  let kb;
+  const ka = Object.keys(a);
+  const kb = Object.keys(b);
   let key;
   let i;
-  try {
-    ka = Object.keys(a);
-    kb = Object.keys(b);
-  } catch (e) {
-    // happens when one is a string literal and the other isn't
-    return false;
-  }
 
   // having the same number of owned properties (keys incorporates
   // hasOwnProperty)

From 13c26da6255f960711025669d0051c40f6eb08dc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Nov 2020 17:09:38 -0500
Subject: [PATCH 1386/2348] perf(utils): add a couple more improvements re:
 #9396

---
 lib/utils.js | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/lib/utils.js b/lib/utils.js
index cdf8e676172..3ebafcd759a 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -82,7 +82,7 @@ exports.deepEqual = function deepEqual(a, b) {
         a.global === b.global;
   }
 
-  if (a === null || b === null || a === undefined || b === undefined) {
+  if (a == null || b == null) {
     return false;
   }
 
@@ -105,10 +105,10 @@ exports.deepEqual = function deepEqual(a, b) {
   }
 
   if (Array.isArray(a) && Array.isArray(b)) {
-    if (a.length !== b.length) {
+    const len = a.length;
+    if (len !== b.length) {
       return false;
     }
-    const len = a.length;
     for (let i = 0; i < len; ++i) {
       if (!deepEqual(a[i], b[i])) {
         return false;
@@ -122,6 +122,7 @@ exports.deepEqual = function deepEqual(a, b) {
   } else if (isMongooseObject(a)) {
     a = a.toObject();
   }
+
   if (b.$__ != null) {
     b = b._doc;
   } else if (isMongooseObject(b)) {
@@ -130,12 +131,11 @@ exports.deepEqual = function deepEqual(a, b) {
 
   const ka = Object.keys(a);
   const kb = Object.keys(b);
-  let key;
-  let i;
+  let kaLength = ka.length;
 
   // having the same number of owned properties (keys incorporates
   // hasOwnProperty)
-  if (ka.length !== kb.length) {
+  if (kaLength !== kb.length) {
     return false;
   }
 
@@ -144,7 +144,7 @@ exports.deepEqual = function deepEqual(a, b) {
   kb.sort();
 
   // ~~~cheap key test
-  for (i = ka.length - 1; i >= 0; i--) {
+  for (let i = kaLength - 1; i >= 0; i--) {
     if (ka[i] !== kb[i]) {
       return false;
     }
@@ -152,8 +152,7 @@ exports.deepEqual = function deepEqual(a, b) {
 
   // equivalent values for every corresponding key, and
   // ~~~possibly expensive deep test
-  for (i = ka.length - 1; i >= 0; i--) {
-    key = ka[i];
+  for (const key of ka) {
     if (!deepEqual(a[key], b[key])) {
       return false;
     }

From 1346469ea0d9c516e304c3f1903f5df2fdf06910 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Nov 2020 20:09:47 -0500
Subject: [PATCH 1387/2348] fix(connection): copy config options from
 connection rather than base connection when calling `useDb()`

Fix #9569
---
 lib/connection.js                             | 9 +++++++++
 lib/drivers/node-mongodb-native/connection.js | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 167e71b865d..5a42ab07a1b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -143,6 +143,10 @@ Object.defineProperty(Connection.prototype, 'readyState', {
  */
 
 Connection.prototype.get = function(key) {
+  if (this.config.hasOwnProperty(key)) {
+    return this.config[key];
+  }
+
   return get(this.options, key);
 };
 
@@ -167,6 +171,11 @@ Connection.prototype.get = function(key) {
  */
 
 Connection.prototype.set = function(key, val) {
+  if (this.config.hasOwnProperty(key)) {
+    this.config[key] = val;
+    return val;
+  }
+
   this.options = this.options || {};
   this.options[key] = val;
   return val;
diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index 57421ad85d3..57e7195448a 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -58,7 +58,7 @@ NativeConnection.prototype.useDb = function(name, options) {
   newConn.collections = {};
   newConn.models = {};
   newConn.replica = this.replica;
-  newConn.config = Object.assign({}, this.base.connection.config, newConn.config);
+  newConn.config = Object.assign({}, this.config, newConn.config);
   newConn.name = this.name;
   newConn.options = this.options;
   newConn._readyState = this._readyState;

From 8ae9ac2604d3705a0249bdbc6503db344b2233dd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 22 Nov 2020 20:45:22 -0500
Subject: [PATCH 1388/2348] test(versioning): remove a couple hard to read
 tests re: #9574

---
 test/versioning.test.js | 51 +++++++++++++++++++++++++++--------------
 1 file changed, 34 insertions(+), 17 deletions(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index 538e49c177c..1cca373779f 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -137,24 +137,9 @@ describe('versioning', function() {
       });
     }
 
-    function test15(err, a) {
-      assert.equal(a._doc.__v, 13, 'version should not be incremented for non-versioned sub-document fields');
-      done();
-    }
-
-    function test14(err, a, b) {
-      assert.ifError(err);
-      assert.equal(a._doc.__v, 13, 'version should not be incremented for non-versioned fields');
-      a.comments[0].dontVersionMeEither.push('value1');
-      b.comments[0].dontVersionMeEither.push('value2');
-      save(a, b, test15);
-    }
-
-    function test13(err, a, b) {
+    function test13(err) {
       assert.ifError(err);
-      a.dontVersionMe.push('value1');
-      b.dontVersionMe.push('value2');
-      save(a, b, test14);
+      done();
     }
 
     function test12(err, a, b) {
@@ -492,6 +477,38 @@ describe('versioning', function() {
     });
   });
 
+  it('should not increment version for non-versioned fields', function() {
+    return co(function*() {
+      const a = new BlogPost({});
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.dontVersionMe.push('value1');
+      b.dontVersionMe.push('value2');
+      yield [a.save(), b.save()];
+
+      assert.equal(a._doc.__v, 0);
+    });
+  });
+
+  it('should not increment version for non-versioned sub-document fields', function() {
+    return co(function*() {
+      const a = new BlogPost({ comments: [{ title: 'test' }] });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.comments[0].dontVersionMeEither.push('value1');
+      b.comments[0].dontVersionMeEither.push('value2');
+      yield [a.save(), b.save()];
+
+      assert.equal(a._doc.__v, 0);
+    });
+  });
+
   describe('versioning is off', function() {
     it('when { safe: false } is set (gh-1520)', function(done) {
       const schema1 = new Schema({ title: String }, { safe: false });

From 93f304bd8541edb65b12413719dd603e2290dfeb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Nov 2020 11:02:30 -0500
Subject: [PATCH 1389/2348] test(versioning): refactor out a couple more tests
 that were hardcoded as sequential function calls

Re: #9574
---
 test/versioning.test.js | 123 ++++++++++++++++++++++++----------------
 1 file changed, 74 insertions(+), 49 deletions(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index 1cca373779f..4718e2c1a25 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -137,52 +137,6 @@ describe('versioning', function() {
       });
     }
 
-    function test13(err) {
-      assert.ifError(err);
-      done();
-    }
-
-    function test12(err, a, b) {
-      assert.ok(err instanceof VersionError);
-      assert.ok(err.stack.indexOf('versioning.test.js') !== -1);
-      assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
-      assert.equal(a.comments.length, 5);
-
-      a.comments.addToSet({ title: 'aven' });
-      a.comments.addToSet({ title: 'avengers' });
-      let d = a.$__delta();
-
-      assert.equal(d[0].__v, undefined, 'version should not be included in where clause');
-      assert.ok(!d[1].$set);
-      assert.ok(d[1].$addToSet);
-      assert.ok(d[1].$addToSet.comments);
-
-      a.comments.$shift();
-      d = a.$__delta();
-      assert.equal(d[0].__v, 12, 'version should be included in where clause');
-      assert.ok(d[1].$set, 'two differing atomic ops on same path should create a $set');
-      assert.ok(d[1].$inc, 'a $set of an array should trigger versioning');
-      assert.ok(!d[1].$addToSet);
-      save(a, b, test13);
-    }
-
-    function test11(err, a, b) {
-      assert.ifError(err);
-      assert.equal(a._doc.__v, 11);
-      assert.equal(a.mixed.arr.length, 6);
-      assert.equal(a.mixed.arr[4].x, 1);
-      assert.equal(a.mixed.arr[5], 'woot');
-      assert.equal(a.mixed.arr[3][0], 10);
-
-      a.comments.addToSet({ title: 'monkey' });
-      b.markModified('comments');
-
-      const d = b.$__delta();
-      assert.ok(d[1].$inc, 'a $set of an array should trigger versioning');
-
-      save(a, b, test12);
-    }
-
     function test10(err, a, b) {
       assert.ifError(err);
       assert.equal(b.meta.nested[2].title, 'two');
@@ -190,9 +144,8 @@ describe('versioning', function() {
       assert.equal(b.meta.nested[1].comments[0].title, 'sub one');
       assert.equal(a._doc.__v, 10);
       assert.equal(a.mixed.arr.length, 3);
-      a.mixed.arr.push([10], { x: 1 }, 'woot');
-      a.markModified('mixed.arr');
-      save(a, b, test11);
+
+      done();
     }
 
     function test9(err, a, b) {
@@ -477,6 +430,78 @@ describe('versioning', function() {
     });
   });
 
+  it('increments version when modifying mixed array', function() {
+    return co(function*() {
+      const a = new BlogPost({ mixed: { arr: [] } });
+      yield a.save();
+
+      assert.equal(a._doc.__v, 0);
+
+      a.mixed.arr.push([10], { x: 1 }, 'test');
+      a.markModified('mixed.arr');
+
+      yield a.save();
+
+      assert.equal(a._doc.__v, 1);
+      assert.equal(a.mixed.arr.length, 3);
+      assert.equal(a.mixed.arr[1].x, 1);
+      assert.equal(a.mixed.arr[2], 'test');
+      assert.equal(a.mixed.arr[0][0], 10);
+    });
+  });
+
+  it('increments version when $set-ing an array', function() {
+    return co(function*() {
+      const a = new BlogPost({});
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.comments.addToSet({ title: 'monkey' });
+      b.markModified('comments');
+
+      const d = b.$__delta();
+      assert.ok(d[1].$inc, 'a $set of an array should trigger versioning');
+
+      yield a.save();
+      const err = yield b.save().then(() => null, err => err);
+
+      assert.ok(err instanceof VersionError);
+      assert.ok(err.stack.indexOf('versioning.test.js') !== -1);
+      assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
+      assert.equal(a.comments.length, 1);
+    });
+  });
+
+  it('increments version and converts to $set when mixing $shift and $addToSet', function() {
+    return co(function*() {
+      const a = new BlogPost({});
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.comments.addToSet({ title: 'aven' });
+      a.comments.addToSet({ title: 'avengers' });
+      let d = a.$__delta();
+
+      assert.equal(d[0].__v, undefined, 'version should not be included in where clause');
+      assert.ok(!d[1].$set);
+      assert.ok(d[1].$addToSet);
+      assert.ok(d[1].$addToSet.comments);
+
+      a.comments.$shift();
+      d = a.$__delta();
+      assert.equal(d[0].__v, 0, 'version should be included in where clause');
+      assert.ok(d[1].$set, 'two differing atomic ops on same path should create a $set');
+      assert.ok(d[1].$inc, 'a $set of an array should trigger versioning');
+      assert.ok(!d[1].$addToSet);
+
+      yield [a.save(), b.save()];
+    });
+  });
+
   it('should not increment version for non-versioned fields', function() {
     return co(function*() {
       const a = new BlogPost({});

From 2d854218297d721eeaa61ea2903cee7fffc847f8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 24 Nov 2020 14:00:33 -0500
Subject: [PATCH 1390/2348] test(versioning): refactor a couple more test cases
 that were treated as sequential function calls

Re: #9574
---
 test/versioning.test.js | 80 ++++++++++++++++++++++++-----------------
 1 file changed, 48 insertions(+), 32 deletions(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index 4718e2c1a25..d118462a1a0 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -137,41 +137,11 @@ describe('versioning', function() {
       });
     }
 
-    function test10(err, a, b) {
-      assert.ifError(err);
-      assert.equal(b.meta.nested[2].title, 'two');
-      assert.equal(b.meta.nested[0].title, 'zero');
-      assert.equal(b.meta.nested[1].comments[0].title, 'sub one');
-      assert.equal(a._doc.__v, 10);
-      assert.equal(a.mixed.arr.length, 3);
-
-      done();
-    }
-
-    function test9(err, a, b) {
-      assert.ifError(err);
-      assert.equal(a.meta.nested.length, 6);
-      assert.equal(a._doc.__v, 10);
-      // nested subdoc property changes should not trigger version increments
-      a.meta.nested[2].title = 'two';
-      b.meta.nested[0].title = 'zero';
-      b.meta.nested[1].comments[0].title = 'sub one';
-      save(a, b, function(err, _a, _b) {
-        assert.ifError(err);
-        assert.equal(a._doc.__v, 10);
-        assert.equal(b._doc.__v, 10);
-        test10(null, _a, _b);
-      });
-    }
-
-    function test8(err, a, b) {
+    function test8(err, a) {
       assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
       assert.equal(a.meta.nested.length, 3);
       assert.equal(a._doc.__v, 8);
-      a.meta.nested.push({ title: 'the' });
-      a.meta.nested.push({ title: 'killing' });
-      b.meta.nested.push({ title: 'biutiful' });
-      save(a, b, test9);
+      done();
     }
 
     function test7(err, a, b) {
@@ -430,6 +400,52 @@ describe('versioning', function() {
     });
   });
 
+  it('increments version on push', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        meta: { nested: [] }
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.meta.nested.push({ title: 'test1' });
+      a.meta.nested.push({ title: 'test2' });
+      b.meta.nested.push({ title: 'test3' });
+      yield [a.save(), b.save()];
+
+      a = yield BlogPost.findById(a);
+      assert.equal(a._doc.__v, 2);
+      assert.deepEqual(a.meta.nested.map(v => v.title), ['test1', 'test2', 'test3']);
+    });
+  });
+
+  it('does not increment version when setting nested paths', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        meta: {
+          nested: [{ title: 'test1' }, { title: 'test2' }, { title: 'test3' }]
+        }
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.meta.nested[2].title = 'two';
+      b.meta.nested[0].title = 'zero';
+      b.meta.nested[1].title = 'sub one';
+
+      yield [a.save(), b.save()];
+      assert.equal(a._doc.__v, 0);
+
+      a = yield BlogPost.findById(a);
+      assert.equal(a.meta.nested[2].title, 'two');
+      assert.equal(a.meta.nested[0].title, 'zero');
+    });
+  });
+
   it('increments version when modifying mixed array', function() {
     return co(function*() {
       const a = new BlogPost({ mixed: { arr: [] } });

From 9b6dcb70733950098716ddda37097dd72aea4d31 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 24 Nov 2020 14:36:56 -0500
Subject: [PATCH 1391/2348] test: fix tests re: #9574

---
 test/versioning.test.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index d118462a1a0..dd9528fb013 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -413,7 +413,8 @@ describe('versioning', function() {
       a.meta.nested.push({ title: 'test1' });
       a.meta.nested.push({ title: 'test2' });
       b.meta.nested.push({ title: 'test3' });
-      yield [a.save(), b.save()];
+      yield a.save();
+      yield b.save();
 
       a = yield BlogPost.findById(a);
       assert.equal(a._doc.__v, 2);

From aa1bf26614612822d3b45a9ff618d6245f3227ec Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 25 Nov 2020 11:08:33 -0500
Subject: [PATCH 1392/2348] chore: release 5.10.16

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index fd55f2c6afc..9ff1f0e9763 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.10.16 / 2020-11-25
+====================
+ * fix(connection): copy config options from connection rather than base connection when calling `useDb()` #9569
+ * fix(schema): support `of` for array type definitions to be consistent with maps #9564
+ * docs(dates): fix broken example reference #9557 [kertof](https://github.com/kertof)
+ * docs(virtualtype): remove unintentional h2 tag re: tj/dox#60 #9568
+
 5.10.15 / 2020-11-16
 ====================
  * fix(array): make sure `Array#toObject()` returns a vanilla JavaScript array in Node.js 6+ #9540
diff --git a/package.json b/package.json
index cbd6ff3e704..f81016d0210 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.15",
+  "version": "5.10.16",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 7a8b24200cd6847ca7e83a42584475c9935b5699 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 26 Nov 2020 08:42:42 -0500
Subject: [PATCH 1393/2348] test: refactor some more offending tests re: #9574

---
 test/versioning.test.js | 106 +++++++++++++++++++++++++---------------
 1 file changed, 67 insertions(+), 39 deletions(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index dd9528fb013..fc0d8ae5e9e 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -137,48 +137,11 @@ describe('versioning', function() {
       });
     }
 
-    function test8(err, a) {
-      assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
-      assert.equal(a.meta.nested.length, 3);
-      assert.equal(a._doc.__v, 8);
-      done();
-    }
-
-    function test7(err, a, b) {
-      assert.ok(/No matching document/.test(err), 'changes to b should not be applied');
-      assert.equal(a.arr.length, 2);
-      assert.equal(a.arr[0][0], 'updated');
-      assert.equal(a.arr[1], 'woot');
-      assert.equal(a._doc.__v, 7);
-      a.meta.nested.$pop();
-      b.meta.nested.$pop();
-      save(a, b, test8);
-    }
-
-    function test6(err, a, b) {
-      assert.ifError(err);
-      assert.equal(a.arr.length, 2);
-      assert.equal(a.arr[0][0], 'updated');
-      assert.equal(a.arr[1], 'using set');
-      assert.equal(a._doc.__v, 6);
-      b.set('arr.0', 'not an array');
-      // should overwrite b's changes, last write wins
-      // force a $set
-      a.arr.pull('using set');
-      a.arr.push('woot', 'woot2');
-      a.arr.$pop();
-      save(a, b, test7);
-    }
-
-    function test5(err, a, b) {
+    function test5(err, a) {
       assert.ifError(err);
       assert.equal(a.arr[0][0], 'updated');
       assert.equal(a._doc.__v, 5);
-      a.set('arr.0', 'not an array');
-      // should overwrite a's changes, last write wins
-      b.arr.pull(10);
-      b.arr.addToSet('using set');
-      save(a, b, test6);
+      done();
     }
 
     function test4(err, a, b) {
@@ -400,6 +363,71 @@ describe('versioning', function() {
     });
   });
 
+  it('allows pull/push after $set', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        arr: ['test1', 10]
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.set('arr.0', 'not an array');
+      // should overwrite a's changes, last write wins
+      b.arr.pull(10);
+      b.arr.addToSet('using set');
+
+      yield a.save();
+      yield b.save();
+
+      a = yield BlogPost.findById(a);
+      assert.deepEqual(a.toObject().arr, ['test1', 'using set']);
+    });
+  });
+
+  it('$set after pull/push throws', function() {
+    return co(function*() {
+      const a = new BlogPost({
+        arr: ['test1', 'using set']
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      b.set('arr.0', 'not an array');
+      // force a $set
+      a.arr.pull('using set');
+      a.arr.push('woot', 'woot2');
+      a.arr.$pop();
+
+      yield a.save();
+      const err = yield b.save().then(() => null, err => err);
+
+      assert.ok(/No matching document/.test(err.message), err.message);
+    });
+  });
+
+  it('doesnt persist conflicting changes', function() {
+    return co(function*() {
+      const a = new BlogPost({
+        meta: { nested: [{ title: 'test1' }, { title: 'test2' }] }
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.meta.nested.$pop();
+      b.meta.nested.$pop();
+      yield a.save();
+      const err = yield b.save().then(() => null, err => err);
+
+      assert.ok(/No matching document/.test(err.message), err.message);
+    });
+  });
+
   it('increments version on push', function() {
     return co(function*() {
       let a = new BlogPost({

From 1c2978e31f4c46be135e6ee69e668027ceb4bf5e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 26 Nov 2020 11:51:04 -0500
Subject: [PATCH 1394/2348] test(versioning): remove messy hardcoded versioning
 tests

Fix #9574
---
 test/versioning.test.js | 225 +++++++++++++++++-----------------------
 1 file changed, 93 insertions(+), 132 deletions(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index fc0d8ae5e9e..7c4efd9af24 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -75,138 +75,6 @@ describe('versioning', function() {
     done();
   });
 
-  it('works', function(done) {
-    const V = BlogPost;
-
-    const doc = new V;
-    doc.title = 'testing versioning';
-    doc.date = new Date;
-    doc.meta.date = new Date;
-    doc.meta.visitors = 34;
-    doc.meta.numbers = [12, 11, 10];
-    doc.meta.nested = [
-      { title: 'does it work?', date: new Date },
-      { title: '1', comments: [{ title: 'this is sub #1' }, { title: 'this is sub #2' }] },
-      { title: '2', comments: [{ title: 'this is sub #3' }, { title: 'this is sub #4' }] },
-      { title: 'hi', date: new Date }
-    ];
-    doc.mixed = { arr: [12, 11, 10] };
-    doc.numbers = [3, 4, 5, 6, 7];
-    doc.comments = [
-      { title: 'comments 0', date: new Date },
-      { title: 'comments 1', comments: [{ title: 'comments.1.comments.1' }, { title: 'comments.1.comments.2' }] },
-      { title: 'coments 2', comments: [{ title: 'comments.2.comments.1' }, { title: 'comments.2.comments.2' }] },
-      { title: 'comments 3', date: new Date }
-    ];
-    doc.arr = [['2d']];
-
-    function save(a, b, cb) {
-      let e;
-      function lookup() {
-        let a1, b1;
-        V.findById(a, function(err, a_) {
-          if (err && !e) {
-            e = err;
-          }
-          a1 = a_;
-          if (a1 && b1) {
-            cb(e, a1, b1);
-          }
-        });
-        V.findById(b, function(err, b_) {
-          if (err && !e) {
-            e = err;
-          }
-          b1 = b_;
-          if (a1 && b1) {
-            cb(e, a1, b1);
-          }
-        });
-      }
-      // make sure that a saves before b
-      a.save(function(err) {
-        if (err) {
-          e = err;
-        }
-        b.save(function(err) {
-          if (err) {
-            e = err;
-          }
-          lookup();
-        });
-      });
-    }
-
-    function test5(err, a) {
-      assert.ifError(err);
-      assert.equal(a.arr[0][0], 'updated');
-      assert.equal(a._doc.__v, 5);
-      done();
-    }
-
-    function test4(err, a, b) {
-      assert.ok(/No matching document/.test(err), err);
-      assert.equal(a._doc.__v, 5);
-      assert.equal(err.version, b._doc.__v - 1);
-      assert.deepEqual(err.modifiedPaths, ['numbers', 'numbers.2']);
-      a.set('arr.0.0', 'updated');
-      const d = a.$__delta();
-      assert.equal(a._doc.__v, d[0].__v, 'version should be added to where clause');
-      assert.ok(!('$inc' in d[1]));
-      save(a, b, test5);
-    }
-
-    function test3(err, a, b) {
-      assert.ifError(err);
-      assert.equal(a.meta.numbers.length, 5);
-      assert.equal(b.meta.numbers.length, 5);
-      assert.equal(-1, a.meta.numbers.indexOf(10));
-      assert.ok(~a.meta.numbers.indexOf(20));
-      assert.equal(a._doc.__v, 4);
-
-      a.numbers.pull(3, 20);
-
-      // should fail
-      b.set('numbers.2', 100);
-      save(a, b, test4);
-    }
-
-    function test2(err, a, b) {
-      assert.ifError(err);
-      assert.equal(a.meta.numbers.length, 5);
-      assert.equal(a._doc.__v, 2);
-      a.meta.numbers.pull(10);
-      b.meta.numbers.push(20);
-      save(a, b, test3);
-    }
-
-    function test1(a, b) {
-      a.meta.numbers.push(9);
-      b.meta.numbers.push(8);
-      save(a, b, test2);
-    }
-
-    doc.save(function(err) {
-      let a, b;
-      assert.ifError(err);
-      // test 2 concurrent ops
-      V.findById(doc, function(err, _a) {
-        assert.ifError(err);
-        a = _a;
-        if (a && b) {
-          test1(a, b);
-        }
-      });
-      V.findById(doc, function(err, _b) {
-        assert.ifError(err);
-        b = _b;
-        if (a && b) {
-          test1(a, b);
-        }
-      });
-    });
-  });
-
   it('versioning without version key', function(done) {
     const V = BlogPost;
 
@@ -363,6 +231,77 @@ describe('versioning', function() {
     });
   });
 
+  it('allows concurrent push', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        meta: {
+          numbers: []
+        }
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.meta.numbers.push(2);
+      b.meta.numbers.push(4);
+
+      yield a.save();
+      yield b.save();
+
+      a = yield BlogPost.findById(a);
+      assert.deepEqual(a.toObject().meta.numbers, [2, 4]);
+      assert.equal(a._doc.__v, 2);
+    });
+  });
+
+  it('allows concurrent push and pull', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        meta: {
+          numbers: [2, 4, 6, 8]
+        }
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.meta.numbers.pull(2);
+      b.meta.numbers.push(10);
+
+      yield [a.save(), b.save()];
+
+      a = yield BlogPost.findById(a);
+      assert.deepEqual(a.toObject().meta.numbers, [4, 6, 8, 10]);
+      assert.equal(a._doc.__v, 2);
+    });
+  });
+
+  it('throws if you set a positional path after pulling', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        meta: {
+          numbers: [2, 4, 6, 8]
+        }
+      });
+      yield a.save();
+      const b = yield BlogPost.findById(a);
+
+      assert.equal(a._doc.__v, 0);
+
+      a.meta.numbers.pull(4, 6);
+      b.set('meta.numbers.2', 7);
+
+      yield a.save();
+      const err = yield b.save().then(() => null, err => err);
+
+      assert.ok(/No matching document/.test(err.message), err.message);
+      a = yield BlogPost.findById(a);
+      assert.equal(a._doc.__v, 1);
+    });
+  });
+
   it('allows pull/push after $set', function() {
     return co(function*() {
       let a = new BlogPost({
@@ -386,6 +325,28 @@ describe('versioning', function() {
     });
   });
 
+  it('should add version to where clause', function() {
+    return co(function*() {
+      let a = new BlogPost({
+        arr: [['before update']]
+      });
+      yield a.save();
+
+      assert.equal(a._doc.__v, 0);
+
+      a.set('arr.0.0', 'updated');
+      const d = a.$__delta();
+      assert.equal(a._doc.__v, d[0].__v, 'version should be added to where clause');
+      assert.ok(!('$inc' in d[1]));
+
+      yield a.save();
+
+      a = yield BlogPost.findById(a);
+      assert.equal(a.arr[0][0], 'updated');
+      assert.equal(a._doc.__v, 0);
+    });
+  });
+
   it('$set after pull/push throws', function() {
     return co(function*() {
       const a = new BlogPost({

From 8d3c844e82a382eef3df19c54f053587e4beb395 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 26 Nov 2020 20:48:50 +0200
Subject: [PATCH 1395/2348] test(document): repro #9585

---
 test/document.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 077e16b7eb7..4897ab22864 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9639,4 +9639,17 @@ describe('document', function() {
       assert.strictEqual(objB.prop.prop, 1);
     });
   });
+
+  it('sets fields after an undefined field (gh-9585)', function() {
+    const personSchema = new Schema({
+      items: { type: Array },
+      email: { type: String }
+    });
+
+    const Person = db.model('Person', personSchema);
+
+
+    const person = new Person({ items: undefined, email: 'test@gmail.com' });
+    assert.equal(person.email, 'test@gmail.com');
+  });
 });

From bafa3d5be77c40d978a1983922600d3cc5eb6d5a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 26 Nov 2020 20:50:37 +0200
Subject: [PATCH 1396/2348] fix(document): fix missing fields after undefined
 field re #9585

---
 lib/document.js | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4f204032d0c..0aad0264b9d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -973,24 +973,26 @@ Document.prototype.$set = function $set(path, val, type, options) {
         options = Object.assign({}, options, { _skipMinimizeTopLevel: true });
       }
 
-      if (typeof path[key] === 'object' &&
-          !utils.isNativeObject(path[key]) &&
-          !utils.isMongooseType(path[key]) &&
-          path[key] != null &&
-          pathtype !== 'virtual' &&
-          pathtype !== 'real' &&
-          pathtype !== 'adhocOrUndefined' &&
-          !(this.$__path(pathName) instanceof MixedSchema) &&
-          !(this.schema.paths[pathName] &&
-          this.schema.paths[pathName].options &&
-          this.schema.paths[pathName].options.ref)) {
+      const someCondition = typeof path[key] === 'object' &&
+                            !utils.isNativeObject(path[key]) &&
+                            !utils.isMongooseType(path[key]) &&
+                            path[key] != null &&
+                            pathtype !== 'virtual' &&
+                            pathtype !== 'real' &&
+                            pathtype !== 'adhocOrUndefined' &&
+                            !(this.$__path(pathName) instanceof MixedSchema) &&
+                            !(this.schema.paths[pathName] &&
+                            this.schema.paths[pathName].options &&
+                            this.schema.paths[pathName].options.ref);
+
+      if (someCondition) {
         this.$__.$setCalled.add(prefix + key);
         this.$set(path[key], prefix + key, constructing, options);
       } else if (strict) {
         // Don't overwrite defaults with undefined keys (gh-3981) (gh-9039)
         if (constructing && path[key] === void 0 &&
             this.get(pathName) !== void 0) {
-          return this;
+          continue;
         }
 
         if (pathtype === 'adhocOrUndefined') {

From 6ba449b8d5c82fdb766d562edef06a036efad8ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Nov 2020 15:24:41 -0500
Subject: [PATCH 1397/2348] refactor(mongoose): use `promiseOrCallback()`
 scoped to Mongoose instance re: #9573

---
 lib/helpers/promiseOrCallback.js |  4 ++--
 lib/index.js                     | 12 ++++++++++--
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/promiseOrCallback.js b/lib/helpers/promiseOrCallback.js
index a1aff55df61..db16d01f27c 100644
--- a/lib/helpers/promiseOrCallback.js
+++ b/lib/helpers/promiseOrCallback.js
@@ -4,7 +4,7 @@ const PromiseProvider = require('../promise_provider');
 
 const emittedSymbol = Symbol.for('mongoose:emitted');
 
-module.exports = function promiseOrCallback(callback, fn, ee) {
+module.exports = function promiseOrCallback(callback, fn, ee, Promise) {
   if (typeof callback === 'function') {
     return fn(function(error) {
       if (error != null) {
@@ -25,7 +25,7 @@ module.exports = function promiseOrCallback(callback, fn, ee) {
     });
   }
 
-  const Promise = PromiseProvider.get();
+  Promise = Promise || PromiseProvider.get();
 
   return new Promise((resolve, reject) => {
     fn(function(error, res) {
diff --git a/lib/index.js b/lib/index.js
index fccb625bd62..1357ee4f354 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -338,7 +338,7 @@ Mongoose.prototype.connect = function(uri, options, callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
   const conn = _mongoose.connection;
 
-  return promiseOrCallback(callback, cb => {
+  return this._promiseOrCallback(callback, cb => {
     conn.openUri(uri, options, err => {
       if (err != null) {
         return cb(err);
@@ -359,7 +359,7 @@ Mongoose.prototype.connect = function(uri, options, callback) {
 Mongoose.prototype.disconnect = function(callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  return promiseOrCallback(callback, cb => {
+  return this._promiseOrCallback(callback, cb => {
     let remaining = _mongoose.connections.length;
     if (remaining <= 0) {
       return cb(null);
@@ -1121,6 +1121,14 @@ Mongoose.prototype.mongo = require('mongodb');
 
 Mongoose.prototype.mquery = require('mquery');
 
+/*!
+ * ignore
+ */
+
+Mongoose.prototype._promiseOrCallback = function(callback, fn, ee) {
+  return promiseOrCallback(callback, fn, ee, this.Promise);
+};
+
 /*!
  * The exports object is an instance of Mongoose.
  *

From a99a6f49b1f3ca14350c8f1868c7545aad8daba1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Nov 2020 15:32:33 -0500
Subject: [PATCH 1398/2348] chore: update highlight.js re: security

---
 package.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index f81016d0210..0938a7887cc 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.16",
+  "version": "5.10.17",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",
@@ -47,7 +47,7 @@
     "dox": "0.3.1",
     "eslint": "7.1.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
-    "highlight.js": "9.1.0",
+    "highlight.js": "9.18.2",
     "lodash.isequal": "4.5.0",
     "lodash.isequalwith": "4.4.0",
     "marked": "1.1.1",

From 5365a9cc2526d96b375e09d2cd49cf09cd8d5054 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 27 Nov 2020 15:32:58 -0500
Subject: [PATCH 1399/2348] chore: release 5.10.17

---
 History.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/History.md b/History.md
index 9ff1f0e9763..95a2ac28ba5 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,7 @@
+5.10.17 / 2020-11-27
+====================
+ * fix(document): allow setting fields after an undefined field #9587 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.10.16 / 2020-11-25
 ====================
  * fix(connection): copy config options from connection rather than base connection when calling `useDb()` #9569

From 5d7a28dd7cb5c43610f06e53316ef860d2880765 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 28 Nov 2020 17:03:57 -0500
Subject: [PATCH 1400/2348] refactor(model): use `_promiseOrCallback()` scoped
 to Mongoose instance for model functions

Re: #9573
---
 lib/connection.js |  2 +-
 lib/model.js      | 30 +++++++++++++++---------------
 2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 5a42ab07a1b..809a844c8c4 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -584,7 +584,7 @@ Connection.prototype._shouldBufferCommands = function _shouldBufferCommands() {
   if (this.config.bufferCommands != null) {
     return this.config.bufferCommands;
   }
-  if (this.base != null && this.base.get('bufferCommands') != null) {
+  if (this.base.get('bufferCommands') != null) {
     return this.base.get('bufferCommands');
   }
   return true;
diff --git a/lib/model.js b/lib/model.js
index 76eba96ef7f..080b9b31ed4 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -479,7 +479,7 @@ Model.prototype.save = function(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return promiseOrCallback(fn, cb => {
+  return this.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
 
     if (parallelSave) {
@@ -934,7 +934,7 @@ Model.prototype.remove = function remove(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return promiseOrCallback(fn, cb => {
+  return this.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
     this.$__remove(options, (err, res) => {
       this.$op = null;
@@ -973,7 +973,7 @@ Model.prototype.deleteOne = function deleteOne(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return promiseOrCallback(fn, cb => {
+  return this.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
     this.$__deleteOne(options, cb);
   }, this.constructor.events);
@@ -1323,7 +1323,7 @@ Model.createCollection = function createCollection(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
@@ -1365,7 +1365,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     this.createCollection(err => {
@@ -1403,7 +1403,7 @@ Model.cleanIndexes = function cleanIndexes(callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     const collection = this.collection;
 
     this.listIndexes((err, indexes) => {
@@ -1480,7 +1480,7 @@ Model.listIndexes = function init(callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     // Buffering
@@ -1531,7 +1531,7 @@ Model.ensureIndexes = function ensureIndexes(options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     _ensureIndexes(this, options || {}, error => {
@@ -3022,7 +3022,7 @@ Model.create = function create(doc, options, callback) {
     }
   }
 
-  return promiseOrCallback(cb, cb => {
+  return this.db.base._promiseOrCallback(cb, cb => {
     cb = this.$wrapCallback(cb);
     if (args.length === 0) {
       return cb(null);
@@ -3224,7 +3224,7 @@ Model.insertMany = function(arr, options, callback) {
     callback = options;
     options = null;
   }
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     this.$__insertMany(arr, options, cb);
   }, this.events);
 };
@@ -3473,7 +3473,7 @@ Model.bulkWrite = function(ops, options, callback) {
   const validations = ops.map(op => castBulkWrite(this, op, options));
 
   callback = this.$handleCallbackError(callback);
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     each(validations, (fn, cb) => fn(cb), error => {
       if (error) {
@@ -3843,7 +3843,7 @@ Model.mapReduce = function mapReduce(o, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
     if (!Model.mapReduce.schema) {
@@ -3989,7 +3989,7 @@ Model.aggregate = function aggregate(pipeline, callback) {
  */
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     const schema = this.schema;
     let paths = Object.keys(schema.paths);
 
@@ -4126,7 +4126,7 @@ Model.geoSearch = function(conditions, options, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     let error;
     if (conditions === undefined || !utils.isObject(conditions)) {
@@ -4264,7 +4264,7 @@ Model.populate = function(docs, paths, callback) {
 
   callback = this.$handleCallbackError(callback);
 
-  return promiseOrCallback(callback, cb => {
+  return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     _populate(_this, docs, paths, cache, cb);
   }, this.events);

From 038b65e78aeb0939f2cd7788ea7cbe82ec2afe48 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 29 Nov 2020 15:02:27 +0200
Subject: [PATCH 1401/2348] test(connection): repro #9597

---
 test/connection.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index 15049eb0a95..f436894df5b 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1239,4 +1239,18 @@ describe('connections:', function() {
     });
   });
 
+
+  it('can use destructured `connect` and `disconnect` (gh-9597)', function() {
+    return co(function* () {
+      const m = new mongoose.Mongoose;
+      const connect = m.connect;
+      const disconnect = m.disconnect;
+
+      const errorOnConnect = yield connect('mongodb://localhost:27017/test_gh9597').then(() => null, err => err);
+      assert.ifError(errorOnConnect);
+
+      const errorOnDisconnect = yield disconnect().then(() => null, err => err);
+      assert.ifError(errorOnDisconnect);
+    });
+  });
 });

From 5ff54cc7c306e60b3e1f23bad45de225689498e2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 29 Nov 2020 15:08:06 +0200
Subject: [PATCH 1402/2348] fix(connection): connect and disconnect can be used
 destructured re #9597

---
 lib/index.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 1357ee4f354..80a8ca5c68b 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -338,7 +338,7 @@ Mongoose.prototype.connect = function(uri, options, callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
   const conn = _mongoose.connection;
 
-  return this._promiseOrCallback(callback, cb => {
+  return _mongoose._promiseOrCallback(callback, cb => {
     conn.openUri(uri, options, err => {
       if (err != null) {
         return cb(err);
@@ -359,7 +359,7 @@ Mongoose.prototype.connect = function(uri, options, callback) {
 Mongoose.prototype.disconnect = function(callback) {
   const _mongoose = this instanceof Mongoose ? this : mongoose;
 
-  return this._promiseOrCallback(callback, cb => {
+  return _mongoose._promiseOrCallback(callback, cb => {
     let remaining = _mongoose.connections.length;
     if (remaining <= 0) {
       return cb(null);

From 0ad1423c730f08026b66ead9dbfc0aa655984649 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Nov 2020 08:19:02 -0500
Subject: [PATCH 1403/2348] chore: release 5.10.18

---
 History.md   | 4 ++++
 package.json | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 95a2ac28ba5..5b513216f65 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,7 @@
+5.10.18 / 2020-11-29
+====================
+ * fix(connection): connect and disconnect can be used destructured #9598 #9597 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.10.17 / 2020-11-27
 ====================
  * fix(document): allow setting fields after an undefined field #9587 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 0938a7887cc..85671fb31aa 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.17",
+  "version": "5.10.18",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 388d7dd4e54ad671805e317c9f8035f9f49588b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Nov 2020 08:30:20 -0500
Subject: [PATCH 1404/2348] test: fix tests re: #9598

---
 test/connection.test.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index f436894df5b..b7a8e345302 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1246,6 +1246,8 @@ describe('connections:', function() {
       const connect = m.connect;
       const disconnect = m.disconnect;
 
+      yield disconnect();
+
       const errorOnConnect = yield connect('mongodb://localhost:27017/test_gh9597').then(() => null, err => err);
       assert.ifError(errorOnConnect);
 

From d5be144f9943aac6fc6bb8809705c5083ebad710 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Nov 2020 08:47:54 -0500
Subject: [PATCH 1405/2348] style: fix lint

---
 lib/model.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 080b9b31ed4..d6691df743c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -45,7 +45,6 @@ const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedIncl
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
 const modifiedPaths = require('./helpers/update/modifiedPaths');
 const parallelLimit = require('./helpers/parallelLimit');
-const promiseOrCallback = require('./helpers/promiseOrCallback');
 const removeDeselectedForeignField = require('./helpers/populate/removeDeselectedForeignField');
 const util = require('util');
 const utils = require('./utils');

From 779f2af3329a4cd0cb91483126387ae51f3c3527 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Nov 2020 08:53:33 -0500
Subject: [PATCH 1406/2348] fix(query): support passing an array to `$type` in
 query filters

Fix #9577
---
 lib/schema/operators/type.js     |  9 ++++++++-
 test/model.query.casting.test.js | 23 +++++++++++++++--------
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/lib/schema/operators/type.js b/lib/schema/operators/type.js
index c8e391ac2ae..952c79007e6 100644
--- a/lib/schema/operators/type.js
+++ b/lib/schema/operators/type.js
@@ -5,8 +5,15 @@
  */
 
 module.exports = function(val) {
+  if (Array.isArray(val)) {
+    if (!val.every(v => typeof v === 'number' || typeof v === 'string')) {
+      throw new Error('$type array values must be strings or numbers');
+    }
+    return val;
+  }
+
   if (typeof val !== 'number' && typeof val !== 'string') {
-    throw new Error('$type parameter must be number or string');
+    throw new Error('$type parameter must be number, string, or array of numbers and strings');
   }
 
   return val;
diff --git a/test/model.query.casting.test.js b/test/model.query.casting.test.js
index 357c7c52a9f..981dfb7249a 100644
--- a/test/model.query.casting.test.js
+++ b/test/model.query.casting.test.js
@@ -204,17 +204,24 @@ describe('model query casting', function() {
     });
   });
 
-  it('works with $type matching', function(done) {
+  it('works with $type matching', function() {
     const B = BlogPostB;
 
-    B.find({ title: { $type: { x: 1 } } }, function(err) {
-      assert.equal(err.message, '$type parameter must be number or string');
+    return co(function*() {
+      yield B.deleteMany({});
 
-      B.find({ title: { $type: 2 } }, function(err, posts) {
-        assert.ifError(err);
-        assert.strictEqual(Array.isArray(posts), true);
-        done();
-      });
+      yield B.collection.insertMany([{ title: 'test' }, { title: 1 }]);
+
+      const err = yield B.find({ title: { $type: { x: 1 } } }).then(() => null, err => err);
+      assert.equal(err.message,
+        '$type parameter must be number, string, or array of numbers and strings');
+
+      let posts = yield B.find({ title: { $type: 2 } });
+      assert.equal(posts.length, 1);
+      assert.equal(posts[0].title, 'test');
+
+      posts = yield B.find({ title: { $type: ['string', 'number'] } });
+      assert.equal(posts.length, 2);
     });
   });
 

From 7324077ce72bf2fdec83a2a8daaa7cd57e16aea5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 29 Nov 2020 15:43:04 -0500
Subject: [PATCH 1407/2348] perf(schema): avoid creating unnecessary objects
 when casting to array

Re: #9588
---
 lib/schema/array.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 828eb1be09a..ef34e0ab77e 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -334,11 +334,11 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     }
 
     if (!(value && value.isMongooseArray)) {
-      value = new MongooseArray(value, this._arrayPath || this.path, doc);
+      value = MongooseArray(value, this._arrayPath || this.path, doc);
     } else if (value && value.isMongooseArray) {
       // We need to create a new array, otherwise change tracking will
       // update the old doc (gh-4449)
-      value = new MongooseArray(value, this._arrayPath || this.path, doc);
+      value = MongooseArray(value, this._arrayPath || this.path, doc);
     }
 
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);

From cab569c51b8acaff313d3e2be52870ee67f8c3c3 Mon Sep 17 00:00:00 2001
From: Rehat Kathuria <rehatkat@gmail.com>
Date: Mon, 30 Nov 2020 12:06:44 +0000
Subject: [PATCH 1408/2348] Amend gender assumption

---
 docs/middleware.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/middleware.pug b/docs/middleware.pug
index a3937b29cf1..862d7462a0b 100644
--- a/docs/middleware.pug
+++ b/docs/middleware.pug
@@ -150,7 +150,7 @@ block content
     Middleware are useful for atomizing model logic. Here are some other ideas:
 
     * complex validation
-    * removing dependent documents (removing a user removes all his blogposts)
+    * removing dependent documents (removing a user removes all their blogposts)
     * asynchronous defaults
     * asynchronous tasks that a certain action triggers
 

From d11bd18be8e0335b563344c4151de81299d6de9b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Nov 2020 12:38:02 -0500
Subject: [PATCH 1409/2348] chore: release 5.10.19

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 5b513216f65..c175668cdb3 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.10.19 / 2020-11-30
+====================
+ * fix(query): support passing an array to `$type` in query filters #9577
+ * perf(schema): avoid creating unnecessary objects when casting to array #9588
+ * docs: make example gender neutral #9601 [rehatkathuria](https://github.com/rehatkathuria)
+
 5.10.18 / 2020-11-29
 ====================
  * fix(connection): connect and disconnect can be used destructured #9598 #9597 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 85671fb31aa..2d1c1c7d896 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.18",
+  "version": "5.10.19",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 90fc14380989b415ec8c81278f9d326f9d7cb4cb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Nov 2020 12:45:35 -0500
Subject: [PATCH 1410/2348] style: fix lint

---
 lib/utils.js        | 2 +-
 test/schema.test.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/utils.js b/lib/utils.js
index 3ebafcd759a..c19fcabfa9f 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -131,7 +131,7 @@ exports.deepEqual = function deepEqual(a, b) {
 
   const ka = Object.keys(a);
   const kb = Object.keys(b);
-  let kaLength = ka.length;
+  const kaLength = ka.length;
 
   // having the same number of owned properties (keys incorporates
   // hasOwnProperty)
diff --git a/test/schema.test.js b/test/schema.test.js
index 8eef1137904..9f3557db1e7 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2554,7 +2554,7 @@ describe('schema', function() {
       assert.throws(() => schema.path('myId').cast('bad'), /Cast to ObjectId failed/);
     });
   });
-  
+
   it('supports `of` for array type definition (gh-9564)', function() {
     const schema = new Schema({
       nums: { type: Array, of: Number },

From 09415693f81374e2f16a9a748984f49f77fdb6d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Nov 2020 16:51:51 -0500
Subject: [PATCH 1411/2348] chore: release 5.11.0

---
 History.md   | 22 ++++++++++++++++++++++
 package.json |  2 +-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c175668cdb3..cb9a805e613 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,25 @@
+5.11.0 / 2020-11-30
+===================
+ * feat: add official TypeScript definitions `index.d.ts` file #8108
+ * feat(connection): add bufferTimeoutMS option that configures how long Mongoose will allow commands to buffer #9469
+ * feat(populate): support populate virtuals with `localField` and `foreignField` as arrays #6608
+ * feat(populate+virtual): feat: support getters on populate virtuals, including `get` option for `Schema#virtual()` #9343
+ * feat(populate+schema): add support for `populate` schematype option that sets default populate options #6029
+ * feat(QueryCursor): execute post find hooks for each doc in query cursor #9345
+ * feat(schema): support overwriting cast logic for individual schematype instances #8407
+ * feat(QueryCursor): make cursor `populate()` in batch when using `batchSize` #9366 [biomorgoth](https://github.com/biomorgoth)
+ * chore: remove changelog from published bundle #9404
+ * feat(model+mongoose): add `overwriteModels` option to bypass `OverwriteModelError` globally #9406
+ * feat(model+query): allow defining middleware for all query methods or all document methods, but not other middleware types #9190
+ * feat(document+model): make change tracking skip saving if new value matches last saved value #9396
+ * perf(utils): major speedup for `deepEqual()` on documents and arrays #9396
+ * feat(schema): support passing a TypeScript enum to `enum` validator in schema #9547 #9546 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(debug): #8963 `shell` option for date format (ISODate) #9532 [FlameFractal](https://github.com/FlameFractal)
+ * feat(document): support square bracket indexing for `get()`, `set()` #9375
+ * feat(document): support array and space-delimited syntax for `Document#$isValid()`, `isDirectSelected()`, `isSelected()`, `$isDefault()` #9474
+ * feat(string): make `minLength` and `maxLength` behave the same as `minlength` and `maxlength` #8777 [m-weeks](https://github.com/m-weeks)
+ * feat(document): add `$parent()` as an alias for `parent()` for documents and subdocuments to avoid path name conflicts #9455
+
 5.10.19 / 2020-11-30
 ====================
  * fix(query): support passing an array to `$type` in query filters #9577
diff --git a/package.json b/package.json
index 09869a9fbd1..a47667536c0 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.10.19",
+  "version": "5.11.0",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9657faa987029222b7e27acc6cf85b8a2fcf02d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Nov 2020 20:43:21 -0500
Subject: [PATCH 1412/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 4fd8986012d..8b1863a2901 100644
--- a/index.pug
+++ b/index.pug
@@ -376,6 +376,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.kasinosivu.com/pikakasinot/">
                 <img class="sponsor" src="https://images.opencollective.com/pikakasinot/5ef0793/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://goread.io/buy-instagram-likes">
+                <img class="sponsor" src="https://goread.io/assets/images/Goreadlogo.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 07b141234827df4ca46085b047126ba2465ac6c4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 30 Nov 2020 20:47:35 -0500
Subject: [PATCH 1413/2348] chore: update opencollective sponsors

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 8b1863a2901..b5c6de66582 100644
--- a/index.pug
+++ b/index.pug
@@ -377,7 +377,7 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/pikakasinot/5ef0793/logo/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://goread.io/buy-instagram-likes">
-                <img class="sponsor" src="https://goread.io/assets/images/Goreadlogo.png" style="height: 100px">
+                <img class="sponsor" src="https://goread.io/assets/images/Goreadlogo.png" style="height: 100px" alt="Buy Instagram Likes">
               </a>
             </div>
           </div>

From 0d9e3c639edeba7ce78430088c06c2d46cbb0dbd Mon Sep 17 00:00:00 2001
From: Alec Gibson <aleckgibson@gmail.com>
Date: Tue, 1 Dec 2020 10:55:17 +0000
Subject: [PATCH 1414/2348] TS: Return `Connection` from `createConnection`

Fixes https://github.com/Automattic/mongoose/issues/9610

This change fixes the TypeScript type definitions so that we return a
full `Connection` object from `createConnection(url)`, not just a
`Promise<Connection>`.
---
 index.d.ts                    | 2 +-
 test/typescript/connection.ts | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 47176bebfe1..9913a9bdfc2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -56,7 +56,7 @@ declare module "mongoose" {
   export var connections: Connection[];
 
   /** Creates a Connection instance. */
-  export function createConnection(uri: string, options?: ConnectOptions): Promise<Connection>;
+  export function createConnection(uri: string, options?: ConnectOptions): Connection & Promise<Connection>;
   export function createConnection(): Connection;
   export function createConnection(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn: Connection) => void): void;
 
diff --git a/test/typescript/connection.ts b/test/typescript/connection.ts
index 1d8f0c19651..6d16fac8afd 100644
--- a/test/typescript/connection.ts
+++ b/test/typescript/connection.ts
@@ -8,4 +8,6 @@ conn.openUri('mongodb://localhost:27017/test').then(() => console.log('Connected
 
 createConnection('mongodb://localhost:27017/test', { useNewUrlParser: true }).then((conn: Connection) => {
   conn.host;
-});
\ No newline at end of file
+});
+
+createConnection('mongodb://localhost:27017/test').close();
\ No newline at end of file

From 43d6bfc3383a7e84c38824ad12dd00f2e242ab52 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Dec 2020 10:55:42 -0500
Subject: [PATCH 1415/2348] fix(index.d.ts): allow using `Types.ObjectId()`
 without `new` in TypeScript

Fix #9608
---
 index.d.ts                   | 13 ++++++++++++-
 test/typescript/main.test.js |  8 ++++++++
 test/typescript/objectid.ts  |  7 +++++++
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/objectid.ts

diff --git a/index.d.ts b/index.d.ts
index 9913a9bdfc2..305f389f388 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1302,10 +1302,21 @@ declare module "mongoose" {
       toObject(options: ToObjectOptions & { flattenMaps?: boolean }): any;
     }
 
-    class ObjectId extends mongodb.ObjectID {
+    var ObjectId: ObjectIdConstructor;
+
+    class _ObjectId extends mongodb.ObjectID {
       _id?: ObjectId;
     }
 
+    // Expose static methods of `mongodb.ObjectID` and allow calling without `new`
+    type ObjectIdConstructor = typeof _ObjectId & {
+      (val?: string | number): ObjectId;
+    };
+
+    // var objectId: mongoose.Types.ObjectId should reference mongodb.ObjectID not
+    //   the ObjectIdConstructor, so we add the interface below
+    interface ObjectId extends mongodb.ObjectID {}
+
     class Subdocument extends Document {
       $isSingleNested: true;
 
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 244e961d7c0..25b5732941a 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -140,6 +140,14 @@ describe('typescript syntax', function() {
     assert.equal(errors.length, 1);
     assert.ok(errors[0].messageText.includes('Property \'create\' does not exist'), errors[0].messageText);
   });
+
+  it('objectid', function() {
+    const errors = runTest('objectid.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/objectid.ts b/test/typescript/objectid.ts
new file mode 100644
index 00000000000..a7f7d60264e
--- /dev/null
+++ b/test/typescript/objectid.ts
@@ -0,0 +1,7 @@
+import { Types } from 'mongoose';
+
+const oid = new Types.ObjectId();
+oid.toHexString();
+oid._id;
+
+Types.ObjectId().toHexString();
\ No newline at end of file

From b2be066bd313cdddc58cba59cd767bc5891175f9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Dec 2020 12:10:56 -0500
Subject: [PATCH 1416/2348] fix(index.d.ts): allow using `$set` in updates

Fix #9609
---
 index.d.ts                 | 2 +-
 test/typescript/queries.ts | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 305f389f388..a4d3ae6aa5e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1720,7 +1720,7 @@ declare module "mongoose" {
   } &
     mongodb.RootQuerySelector<T>;
   
-  export type UpdateQuery<T> = mongodb.UpdateQuery<T> & mongodb.MatchKeysAndValues<T>;
+  export type UpdateQuery<T> = mongodb.UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;
 
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index b39561b04e6..72ed8fd9e29 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -5,6 +5,7 @@ const schema: Schema = new Schema({ name: { type: 'String' } });
 interface ITest extends Document {
   _id?: Types.ObjectId,
   name?: string;
+  age?: number;
 }
 
 const Test = model<ITest>('Test', schema);
@@ -22,5 +23,7 @@ Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
 
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).then((res: ITest | null) => console.log(res));
+Test.findOneAndUpdate({ name: 'test' }, { $set: { name: 'test2' } }).then((res: ITest | null) => console.log(res));
+Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest | null) => console.log(res));
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
\ No newline at end of file

From 13140c019edcfaaec3df3a4a1132671675f2178d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Dec 2020 12:38:04 -0500
Subject: [PATCH 1417/2348] fix(index.d.ts): add missing SchemaOptions

Re: #9606
---
 docs/guide.pug |  20 ++++++
 index.d.ts     | 175 ++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 194 insertions(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 5a4df7761f9..92f54d43121 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -421,6 +421,7 @@ block content
     - [bufferTimeoutMS](#bufferTimeoutMS)
     - [capped](#capped)
     - [collection](#collection)
+    - [discriminatorKey](#discriminatorKey)
     - [id](#id)
     - [_id](#_id)
     - [minimize](#minimize)
@@ -545,6 +546,25 @@ block content
     const dataSchema = new Schema({..}, { collection: 'data' });
     ```
 
+    <h3 id="discriminatorKey"><a href="#discriminatorKey">option: discriminatorKey</a></h3>
+
+    When you define a [discriminator](/docs/discriminators.html), Mongoose adds a path to your
+    schema that stores which discriminator a document is an instance of. By default, Mongoose
+    adds an `__t` path, but you can set `discriminatorKey` to overwrite this default.
+
+    ```javascript
+    const baseSchema = new Schema({}, { discriminatorKey: 'type' });
+    const BaseModel = mongoose.model('Test', baseSchema);
+
+    const personSchema = new Schema({ name: String });
+    const PersonModel = BaseModel.discriminator('Person', personSchema);
+
+    const doc = new PersonModel({ name: 'James T. Kirk' });
+    // Without `discriminatorKey`, Mongoose would store the discriminator
+    // key in `__t` instead of `type`
+    doc.type; // 'Person'
+    ```
+
     <h3 id="id"><a href="#id">option: id</a></h3>
 
     Mongoose assigns each of your schemas an `id` virtual getter by default
diff --git a/index.d.ts b/index.d.ts
index a4d3ae6aa5e..799f7432fdd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -745,6 +745,17 @@ declare module "mongoose" {
     j?: boolean;
     w?: number | string;
     wtimeout?: number;
+    safe?: boolean | WriteConcern;
+  }
+
+  interface WriteConcern {
+    j?: boolean;
+    w?: number | 'majority' | TagSet;
+    wtimeout?: number;
+  }
+
+  interface TagSet {
+    [k: string]: string;
   }
 
   interface InsertManyOptions {
@@ -857,7 +868,7 @@ declare module "mongoose" {
     /**
      * Create a new schema
      */
-    constructor(definition?: SchemaDefinition);
+    constructor(definition?: SchemaDefinition, options?: SchemaOptions);
 
     /** Adds key path / schema type pairs to this schema. */
     add(obj: SchemaDefinition | Schema, prefix?: string): this;
@@ -946,6 +957,168 @@ declare module "mongoose" {
     [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Array<Schema> | Array<SchemaTypeOptions<any>>;
   }
 
+  interface SchemaOptions {
+    /**
+     * By default, Mongoose's init() function creates all the indexes defined in your model's schema by
+     * calling Model.createIndexes() after you successfully connect to MongoDB. If you want to disable
+     * automatic index builds, you can set autoIndex to false.
+     */
+    autoIndex?: boolean;
+    /**
+     * If set to `true`, Mongoose will call Model.createCollection() to create the underlying collection
+     * in MongoDB if autoCreate is set to true. Calling createCollection() sets the collection's default
+     * collation based on the collation option and establishes the collection as a capped collection if
+     * you set the capped schema option.
+     */
+    autoCreate?: boolean;
+    /**
+     * By default, mongoose buffers commands when the connection goes down until the driver manages to reconnect.
+     * To disable buffering, set bufferCommands to false.
+     */
+    bufferCommands?: boolean;
+    /**
+     * If bufferCommands is on, this option sets the maximum amount of time Mongoose buffering will wait before
+     * throwing an error. If not specified, Mongoose will use 10000 (10 seconds).
+     */
+    bufferTimeoutMS?: number;
+    /**
+     * Mongoose supports MongoDBs capped collections. To specify the underlying MongoDB collection be capped, set
+     * the capped option to the maximum size of the collection in bytes.
+     */
+    capped?: boolean | number | { size?: number; max?: number; autoIndexId?: boolean; };
+    /** Sets a default collation for every query and aggregation. */
+    collation?: mongodb.CollationDocument;
+    /**
+     * Mongoose by default produces a collection name by passing the model name to the utils.toCollectionName
+     * method. This method pluralizes the name. Set this option if you need a different name for your collection.
+     */
+    collection?: string;
+    /**
+     * When you define a [discriminator](/docs/discriminators.html), Mongoose adds a path to your
+     * schema that stores which discriminator a document is an instance of. By default, Mongoose
+     * adds an `__t` path, but you can set `discriminatorKey` to overwrite this default.
+     */
+    discriminatorKey?: string;
+    /** defaults to false. */
+    emitIndexErrors?: boolean;
+    excludeIndexes?: any;
+    /**
+     * Mongoose assigns each of your schemas an id virtual getter by default which returns the document's _id field
+     * cast to a string, or in the case of ObjectIds, its hexString.
+     */
+    id?: boolean;
+    /**
+     * Mongoose assigns each of your schemas an _id field by default if one is not passed into the Schema
+     * constructor. The type assigned is an ObjectId to coincide with MongoDB's default behavior. If you
+     * don't want an _id added to your schema at all, you may disable it using this option.
+     */
+    _id?: boolean;
+    /**
+     * Mongoose will, by default, "minimize" schemas by removing empty objects. This behavior can be
+     * overridden by setting minimize option to false. It will then store empty objects.
+     */
+    minimize?: boolean;
+    /**
+     * Optimistic concurrency is a strategy to ensure the document you're updating didn't change between when you
+     * loaded it using find() or findOne(), and when you update it using save(). Set to `true` to enable
+     * optimistic concurrency.
+     */
+    optimisticConcurrency?: boolean;
+    /**
+     * Allows setting query#read options at the schema level, providing us a way to apply default ReadPreferences
+     * to all queries derived from a model.
+     */
+    read?: string;
+    /** Allows setting write concern at the schema level. */
+    writeConcern?: WriteConcern;
+    /** defaults to true. */
+    safe?: boolean | { w?: number | string; wtimeout?: number; j?: boolean };
+    /**
+     * The shardKey option is used when we have a sharded MongoDB architecture. Each sharded collection is
+     * given a shard key which must be present in all insert/update operations. We just need to set this
+     * schema option to the same shard key and we'll be all set.
+     */
+    shardKey?: object;
+    /**
+     * For backwards compatibility, the strict option does not apply to the filter parameter for queries.
+     * Mongoose has a separate strictQuery option to toggle strict mode for the filter parameter to queries.
+     */
+    strictQuery?: boolean | "throw";
+    /**
+     * The strict option, (enabled by default), ensures that values passed to our model constructor that were not
+     * specified in our schema do not get saved to the db.
+     */
+    strict?: boolean | "throw";
+    /** Exactly the same as the toObject option but only applies when the document's toJSON method is called. */
+    toJSON?: ToObjectOptions;
+    /**
+     * Documents have a toObject method which converts the mongoose document into a plain JavaScript object.
+     * This method accepts a few options. Instead of applying these options on a per-document basis, we may
+     * declare the options at the schema level and have them applied to all of the schema's documents by
+     * default.
+     */
+    toObject?: ToObjectOptions;
+    /**
+     * By default, if you have an object with key 'type' in your schema, mongoose will interpret it as a
+     * type declaration. However, for applications like geoJSON, the 'type' property is important. If you want to
+     * control which key mongoose uses to find type declarations, set the 'typeKey' schema option.
+     */
+    typeKey?: string;
+    /**
+     * Write operations like update(), updateOne(), updateMany(), and findOneAndUpdate() only check the top-level
+     * schema's strict mode setting. Set to `true` to use the child schema's `strict` mode setting.
+     */
+    useNestedStrict?: boolean;
+    /** defaults to false */
+    usePushEach?: boolean;
+    /**
+     * By default, documents are automatically validated before they are saved to the database. This is to
+     * prevent saving an invalid document. If you want to handle validation manually, and be able to save
+     * objects which don't pass validation, you can set validateBeforeSave to false.
+     */
+    validateBeforeSave?: boolean;
+    /**
+     * The versionKey is a property set on each document when first created by Mongoose. This keys value
+     * contains the internal revision of the document. The versionKey option is a string that represents
+     * the path to use for versioning. The default is '__v'.
+     */
+    versionKey?: string | boolean;
+    /**
+     * By default, Mongoose will automatically select() any populated paths for you, unless you explicitly exclude them.
+     */
+    selectPopulatedPaths?: boolean;
+    /**
+     * skipVersioning allows excluding paths from versioning (i.e., the internal revision will not be
+     * incremented even if these paths are updated). DO NOT do this unless you know what you're doing.
+     * For subdocuments, include this on the parent document using the fully qualified path.
+     */
+    skipVersioning?: any;
+    /**
+     * Validation errors in a single nested schema are reported
+     * both on the child and on the parent schema.
+     * Set storeSubdocValidationError to false on the child schema
+     * to make Mongoose only report the parent error.
+     */
+    storeSubdocValidationError?: boolean;
+    /**
+     * The timestamps option tells mongoose to assign createdAt and updatedAt fields to your schema. The type
+     * assigned is Date. By default, the names of the fields are createdAt and updatedAt. Customize the
+     * field names by setting timestamps.createdAt and timestamps.updatedAt.
+     */
+    timestamps?: boolean | SchemaTimestampsConfig;
+    /**
+     * Determines whether a type set to a POJO becomes
+     * a Mixed path or a Subdocument (defaults to true).
+     */
+    typePojoToMixed?:boolean;
+  }
+
+  interface SchemaTimestampsConfig {
+    createdAt?: boolean | string;
+    updatedAt?: boolean | string;
+    currentTime?: () => (Date | number);
+  }
+
   interface SchemaTypeOptions<T> {
     type?: T;
 

From e665a9556f2a15984d1b9b8de8c4e6122fc6b666 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Dec 2020 13:09:10 -0500
Subject: [PATCH 1418/2348] test: add test covering SchemaOptions

---
 test/typescript/createBasicSchemaDefinition.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 1509bee635c..d1ff539e59e 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -1,6 +1,7 @@
 import { Schema, model, Document } from 'mongoose';
 
-const schema: Schema = new Schema({ name: { type: 'String' } });
+const schema: Schema = new Schema({ name: { type: 'String' } },
+  { collection: 'mytest', versionKey: '_version' });
 
 interface ITest extends Document {
   name?: string;

From 1f36f61acf71ce6e28d773af0888ef7d3aaeb1d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Dec 2020 15:06:18 -0500
Subject: [PATCH 1419/2348] chore: release 5.11.1

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index cb9a805e613..85780876c02 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.11.1 / 2020-12-01
+===================
+ * fix(index.d.ts): add missing SchemaOptions #9606
+ * fix(index.d.ts): allow using `$set` in updates #9609
+ * fix(index.d.ts): add support for using return value of `createConnection()` as a connection as well as a promise #9612 #9610 [alecgibson](https://github.com/alecgibson)
+ * fix(index.d.ts): allow using `Types.ObjectId()` without `new` in TypeScript #9608
+
 5.11.0 / 2020-11-30
 ===================
  * feat: add official TypeScript definitions `index.d.ts` file #8108
diff --git a/package.json b/package.json
index a47667536c0..b0578ad4d06 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.0",
+  "version": "5.11.1",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 645a45bc6b87b1581149db49532a9366e434db9b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Dec 2020 19:23:51 -0500
Subject: [PATCH 1420/2348] fix(index.d.ts): add missing `new` and
 `returnOriginal` options to QueryOptions, add missing model static properties

Fix #9615
Re: #9616
---
 index.d.ts | 64 ++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 48 insertions(+), 16 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 799f7432fdd..12939b5242b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -525,6 +525,9 @@ declare module "mongoose" {
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: any, res: mongodb.BulkWriteOpResultObject) => void): void;
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions): Promise<mongodb.BulkWriteOpResultObject>;
 
+    /** Collection the model uses. */
+    collection: Collection;
+
     /** Creates a `count` query: counts the number of documents that match `filter`. */
     count(callback?: (err: any, count: number) => void): Query<number, T>;
     count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
@@ -555,6 +558,9 @@ declare module "mongoose" {
     createIndexes(options: any): Promise<void>;
     createIndexes(options: any, callback?: (err: any) => void): Promise<void>;
 
+    /** Connection the model uses. */
+    db: Connection;
+
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
@@ -692,6 +698,9 @@ declare module "mongoose" {
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
     replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
 
+    /** Schema the model uses. */
+    schema: Schema;
+
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
@@ -709,32 +718,55 @@ declare module "mongoose" {
   }
 
   interface QueryOptions {
-    tailable?: number;
-    sort?: any;
-    limit?: number;
-    skip?: number;
-    maxscan?: number;
     batchSize?: number;
+    collation?: mongodb.CollationDocument;
     comment?: any;
-    snapshot?: any;
-    readPreference?: mongodb.ReadPreferenceMode;
+    explain?: any;
     hint?: any;
-    upsert?: boolean;
-    writeConcern?: any;
-    timestamps?: boolean;
+    /**
+     * If truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document.
+     */
+    lean?: boolean | any;
+    limit?: number;
+    maxTimeMS?: number;
+    maxscan?: number;
+    multi?: boolean;
+    /**
+     * By default, `findOneAndUpdate()` returns the document as it was **before**
+     * `update` was applied. If you set `new: true`, `findOneAndUpdate()` will
+     * instead give you the object after `update` was applied.
+     */
+    new?: boolean;
     omitUndefined?: boolean;
     overwriteDiscriminatorKey?: boolean;
-    lean?: boolean | any;
     populate?: string;
     projection?: any;
-    maxTimeMS?: number;
-    useFindAndModify?: boolean;
+    /**
+     * if true, returns the raw result from the MongoDB driver
+     */
     rawResult?: boolean;
-    collation?: mongodb.CollationDocument;
+    readPreference?: mongodb.ReadPreferenceMode;
+    /**
+     * An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
+     */
+    returnOriginal?: boolean;
+    /** The session associated with this query. */
     session?: mongodb.ClientSession;
-    explain?: any;
-    multi?: boolean;
+    skip?: number;
+    snapshot?: any;
+    sort?: any;
+    /** overwrites the schema's strict mode option */
     strict?: boolean | string;
+    tailable?: number;
+    /**
+     * If set to `false` and schema-level timestamps are enabled,
+     * skip timestamps for this update. Note that this allows you to overwrite
+     * timestamps. Does nothing if schema-level timestamps are not set.
+     */
+    timestamps?: boolean;
+    upsert?: boolean;
+    useFindAndModify?: boolean;
+    writeConcern?: any;
   }
 
   interface SaveOptions {

From 14d75d1ae59e4c8b83bca9cdb15898997aee70f7 Mon Sep 17 00:00:00 2001
From: Alec Gibson <aleckgibson@gmail.com>
Date: Wed, 2 Dec 2020 07:55:46 +0000
Subject: [PATCH 1421/2348] fix: TypeScript Intellisense

This change aims to fix intellisense for developing type definitions in
mongoose.

In `.ts` files, we currently get a compilation warning from TypeScript
when trying to `import mongoose from 'mongoose'`:

```
Cannot find module 'mongoose' or its corresponding type declarations.ts(2307)
```

As such, none of the intellisense in VS Code works correctly.

This change moves the TypeScript configuration out of our test file, and
into a `tsconfig.json`, where IDEs will be able to find it and use it to
enable Intellisense for better TypeScript typings development.
---
 test/typescript/main.test.js  | 7 +------
 test/typescript/tsconfig.json | 9 +++++++++
 2 files changed, 10 insertions(+), 6 deletions(-)
 create mode 100644 test/typescript/tsconfig.json

diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 25b5732941a..3a739ab7af7 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -2,12 +2,7 @@
 
 const assert = require('assert');
 const typescript = require('typescript');
-
-const tsconfig = {
-  allowSyntheticDefaultImports: true,
-  esModuleInterop: true,
-  outDir: `${__dirname}/dist`
-};
+const tsconfig = require('./tsconfig.json');
 
 describe('typescript syntax', function() {
   this.timeout(5000);
diff --git a/test/typescript/tsconfig.json b/test/typescript/tsconfig.json
new file mode 100644
index 00000000000..0ebf21f8742
--- /dev/null
+++ b/test/typescript/tsconfig.json
@@ -0,0 +1,9 @@
+{
+  "allowSyntheticDefaultImports": true,
+  "esModuleInterop": true,
+  "outDir": "test/dist",
+  "include": [
+    "./**/*.ts",
+    "../../index.d.ts"
+  ]
+}

From dd9e0fa8db64a0404e38fa22a12a408ea2478ae2 Mon Sep 17 00:00:00 2001
From: Alec Gibson <aleckgibson@gmail.com>
Date: Wed, 2 Dec 2020 08:26:57 +0000
Subject: [PATCH 1422/2348] fix(index.d.ts): allow `useCreateIndex` in
 connection options

Updated the TypeScript example to mirror the example given in the
[deprecation warning docs][1].

[1]: https://mongoosejs.com/docs/deprecations.html
---
 index.d.ts                       | 2 ++
 test/typescript/connectSyntax.ts | 8 ++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 12939b5242b..5dfbe2d4b6d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -127,6 +127,8 @@ declare module "mongoose" {
     useFindAndModify?: boolean;
     /** Set to `true` to make Mongoose automatically call `createCollection()` on every model created on this connection. */
     autoCreate?: boolean;
+    /** False by default. If `true`, this connection will use `createIndex()` instead of `ensureIndex()` for automatic index builds via `Model.init()`. */
+    useCreateIndex?: boolean;
   }
 
   class Connection extends events.EventEmitter {
diff --git a/test/typescript/connectSyntax.ts b/test/typescript/connectSyntax.ts
index bac6d0d3f1a..513c38d460a 100644
--- a/test/typescript/connectSyntax.ts
+++ b/test/typescript/connectSyntax.ts
@@ -1,8 +1,12 @@
 import { connect } from 'mongoose';
 
 // Promise
-connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }).
-  then(mongoose => console.log(mongoose.connect));
+connect('mongodb://localhost:27017/test', {
+  useNewUrlParser: true,
+  useFindAndModify: true,
+  useCreateIndex: true,
+  useUnifiedTopology: true,
+}).then(mongoose => console.log(mongoose.connect));
 
 // Callback
 connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }, (err: Error) => {

From af14db2bcbb017c4aa59a54ae6860cc3fb61aa63 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 16:36:47 -0500
Subject: [PATCH 1423/2348] fix(index.d.ts): add missing `Schema#obj`,
 `Schema#statics`, `Schema#methods`, `Schema#query` properties

Fix #9622
---
 index.d.ts | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 5dfbe2d4b6d..f98e85e9d3d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -938,6 +938,9 @@ declare module "mongoose" {
     method(name: string, fn: Function, opts?: any): this;
     method(methods: any): this;
 
+    /** The original object passed to the schema constructor */
+    obj: any;
+
     /** Gets/sets schema paths. */
     path(path: string): SchemaType;
     path(path: string, constructor: any): this;
@@ -965,6 +968,9 @@ declare module "mongoose" {
     pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
+    /** Object of currently defined query helpers on this schema. */
+    query: any;
+
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
 
@@ -980,6 +986,9 @@ declare module "mongoose" {
     /** Adds static "class" methods to Models compiled from this schema. */
     static(name: string, fn: Function): this;
 
+    /** Object of currently defined statics on this schema. */
+    statics: any;
+
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;
 

From eafee6d95ec7f83752bdce4f503a82edd1baf7e2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 16:42:48 -0500
Subject: [PATCH 1424/2348] fix(index.d.ts): support defining schema paths as
 arrays of functions

Fix #9617
---
 index.d.ts                                     | 5 ++++-
 test/typescript/createBasicSchemaDefinition.ts | 7 +++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index f98e85e9d3d..c480126696a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -938,6 +938,9 @@ declare module "mongoose" {
     method(name: string, fn: Function, opts?: any): this;
     method(methods: any): this;
 
+    /** Object of currently defined methods on this schema. */
+    methods: any;
+
     /** The original object passed to the schema constructor */
     obj: any;
 
@@ -997,7 +1000,7 @@ declare module "mongoose" {
   }
 
   interface SchemaDefinition {
-    [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Array<Schema> | Array<SchemaTypeOptions<any>>;
+    [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[];
   }
 
   interface SchemaOptions {
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index d1ff539e59e..7b8dbe17ff5 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -1,10 +1,13 @@
 import { Schema, model, Document } from 'mongoose';
 
-const schema: Schema = new Schema({ name: { type: 'String' } },
-  { collection: 'mytest', versionKey: '_version' });
+const schema: Schema = new Schema({
+  name: { type: 'String' },
+  tags: [String]
+}, { collection: 'mytest', versionKey: '_version' });
 
 interface ITest extends Document {
   name?: string;
+  tags?: string[];
 }
 
 const Test = model<ITest>('Test', schema);

From af845b2104d07d6d1be2b8d2c9663176254ac875 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 16:49:53 -0500
Subject: [PATCH 1425/2348] fix(index.d.ts): add missing global `get()` and
 `set()`

Fix #9616
---
 index.d.ts                   | 6 ++++++
 test/typescript/global.ts    | 5 +++++
 test/typescript/main.test.js | 8 ++++++++
 3 files changed, 19 insertions(+)
 create mode 100644 test/typescript/global.ts

diff --git a/index.d.ts b/index.d.ts
index c480126696a..240cbac1944 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -70,6 +70,9 @@ declare module "mongoose" {
   export function disconnect(): Promise<void>;
   export function disconnect(cb: (err: CallbackError) => void): void;
 
+  /** Gets mongoose options */
+  export function get(key: string): any;
+
   /**
    * Returns true if Mongoose can cast the given value to an ObjectId, or
    * false otherwise.
@@ -97,6 +100,9 @@ declare module "mongoose" {
   /** Getter/setter around function for pluralizing collection names. */
   export function pluralize(fn?: (str: string) => string): (str: string) => string;
 
+  /** Sets mongoose options */
+  export function set(key: string, value: any): void;
+
   /**
    * _Requires MongoDB >= 3.6.0._ Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
    * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
diff --git a/test/typescript/global.ts b/test/typescript/global.ts
new file mode 100644
index 00000000000..cb851ffb3e1
--- /dev/null
+++ b/test/typescript/global.ts
@@ -0,0 +1,5 @@
+import mongoose from 'mongoose';
+
+mongoose.set('useCreateIndex', true);
+
+mongoose.get('useCreateIndex');
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 25b5732941a..407f8f1e6b8 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -148,6 +148,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('global', function() {
+    const errors = runTest('global.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {

From ef2a4c799ecafe35a55273a10387cd387681e823 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 17:00:56 -0500
Subject: [PATCH 1426/2348] fix(index.d.ts): add automatic `_id` for Document,
 support creating Mongoose globals and accessing collection name

Fix #9618
---
 index.d.ts                | 22 +++++++++++++++-------
 lib/document.js           |  2 +-
 test/typescript/global.ts | 10 +++++++++-
 3 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 240cbac1944..70173abd778 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -23,6 +23,12 @@ declare module "mongoose" {
    */
   export type Mixed = Schema.Types.Mixed;
 
+  /**
+   * Mongoose constructor. The exports object of the `mongoose` module is an instance of this
+   * class. Most apps will only use this one instance.
+   */
+  export var Mongoose: new (options?: object | null) => typeof mongoose;
+
   /**
    * The Mongoose Number [SchemaType](/docs/schematypes.html). Used for
    * declaring paths in your schema that Mongoose should cast to numbers.
@@ -285,7 +291,9 @@ declare module "mongoose" {
     watch(pipeline?: Array<any>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
   }
 
-  class Collection {}
+  class Collection {
+    name: string;
+  }
 
   class Document {
     constructor(doc?: any);
@@ -423,12 +431,12 @@ declare module "mongoose" {
      */
     isModified(path?: string | Array<string>): boolean;
 
-    /** Checks if `path` was selected in the source query which initialized this document. */
-    isSelected(path: string): boolean;
-
     /** Boolean flag specifying if the document is new. */
     isNew: boolean;
 
+    /** Checks if `path` was selected in the source query which initialized this document. */
+    isSelected(path: string): boolean;
+
     /** Marks the path as having pending changes to write to the db. */
     markModified(path: string, scope?: any): void;
 
@@ -474,6 +482,9 @@ declare module "mongoose" {
     save(options?: SaveOptions, fn?: (err: CallbackError, doc: this) => void): void;
     save(fn?: (err: CallbackError, doc: this) => void): void;
 
+    /** The document's schema. */
+    schema: Schema;
+
     /** Sets the value of a path, or many paths. */
     set(path: string, val: any, options?: any): this;
     set(path: string, val: any, type: any, options?: any): this;
@@ -502,9 +513,6 @@ declare module "mongoose" {
 
     /** Executes registered validation rules (skipping asynchronous validators) for this document. */
     validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
-
-    /** The documents schema. */
-    schema: Schema;
   }
 
   export var Model: Model<any>;
diff --git a/lib/document.js b/lib/document.js
index 0e0b5e288d5..5e9a541460b 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -206,7 +206,7 @@ for (const i in EventEmitter.prototype) {
 }
 
 /**
- * The documents schema.
+ * The document's schema.
  *
  * @api public
  * @property schema
diff --git a/test/typescript/global.ts b/test/typescript/global.ts
index cb851ffb3e1..469afde2b30 100644
--- a/test/typescript/global.ts
+++ b/test/typescript/global.ts
@@ -2,4 +2,12 @@ import mongoose from 'mongoose';
 
 mongoose.set('useCreateIndex', true);
 
-mongoose.get('useCreateIndex');
\ No newline at end of file
+mongoose.get('useCreateIndex');
+
+const m: mongoose.Mongoose = new mongoose.Mongoose();
+
+m.set('useUnifiedTopology', true);
+
+m.connect('mongodb://localhost:27017/test').then(() => {
+  console.log('Connected!');
+});
\ No newline at end of file

From 4b223e4055f5c33dcb361ac793097d9cb1da6234 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 17:21:12 -0500
Subject: [PATCH 1427/2348] fix(index.d.ts): add missing query options and
 model  `findById()` function

Re: #9620
---
 index.d.ts | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 70173abd778..85643c9a3c8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -124,6 +124,8 @@ declare module "mongoose" {
 
   type Mongoose = typeof mongoose;
 
+  interface ClientSession extends mongodb.ClientSession {}
+
   interface ConnectOptions extends mongodb.MongoClientOptions {
     /** Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection. */
     bufferCommands?: boolean;
@@ -577,6 +579,20 @@ declare module "mongoose" {
     /** Connection the model uses. */
     db: Connection;
 
+    /**
+     * Deletes all of the documents that match `conditions` from the collection.
+     * Behaves like `remove()`, but deletes all documents that match `conditions`
+     * regardless of the `single` option.
+     */
+    deleteMany(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T>;
+
+    /**
+     * Deletes the first document that matches `conditions` from the collection.
+     * Behaves like `remove()`, but deletes at most one document regardless of the
+     * `single` option.
+     */
+    deleteOne(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T>;
+
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
@@ -590,6 +606,13 @@ declare module "mongoose" {
      */
     events: NodeJS.EventEmitter;
 
+    /**
+     * Finds a single document by its _id field. `findById(id)` is almost*
+     * equivalent to `findOne({ _id: id })`. If you want to query by a document's
+     * `_id`, use `findById()` instead of `findOne()`.
+     */
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<T | null, T>;
+
     /** Finds one document. */
     findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<T | null, T>;
 
@@ -734,10 +757,13 @@ declare module "mongoose" {
   }
 
   interface QueryOptions {
+    arrayFilters?: { [key: string]: any }[];
     batchSize?: number;
     collation?: mongodb.CollationDocument;
     comment?: any;
+    context?: string;
     explain?: any;
+    fields?: any | string;
     hint?: any;
     /**
      * If truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document.
@@ -747,6 +773,7 @@ declare module "mongoose" {
     maxTimeMS?: number;
     maxscan?: number;
     multi?: boolean;
+    multipleCastError?: boolean;
     /**
      * By default, `findOneAndUpdate()` returns the document as it was **before**
      * `update` was applied. If you set `new: true`, `findOneAndUpdate()` will
@@ -754,6 +781,7 @@ declare module "mongoose" {
      */
     new?: boolean;
     omitUndefined?: boolean;
+    overwrite?: boolean;
     overwriteDiscriminatorKey?: boolean;
     populate?: string;
     projection?: any;
@@ -766,8 +794,10 @@ declare module "mongoose" {
      * An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
      */
     returnOriginal?: boolean;
+    runValidators?: boolean;
     /** The session associated with this query. */
     session?: mongodb.ClientSession;
+    setDefaultsOnInsert?: boolean;
     skip?: number;
     snapshot?: any;
     sort?: any;

From 991b4fbf49ac1ae381d62246753131558f840b86 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 17:32:26 -0500
Subject: [PATCH 1428/2348] chore: release 5.11.2

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 85780876c02..456d3a6258d 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.11.2 / 2020-12-02
+===================
+ * fix(index.d.ts): add missing query options and model `findById()` function #9626 #9620
+ * fix(index.d.ts): support defining schema paths as arrays of functions #9617
+ * fix(index.d.ts): add automatic `_id` for Document, support creating Mongoose globals and accessing collection name #9618
+ * fix(index.d.ts): add missing global `get()` and `set()` #9616
+ * fix(index.d.ts): add missing `new` and `returnOriginal` options to QueryOptions, add missing model static properties #9627 #9616 #9615
+ * fix(index.d.ts): allow `useCreateIndex` in connection options #9621
+
 5.11.1 / 2020-12-01
 ===================
  * fix(index.d.ts): add missing SchemaOptions #9606
diff --git a/package.json b/package.json
index b0578ad4d06..6c222f7f501 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.1",
+  "version": "5.11.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 3123bec72fddc945931884d9b795b10c3de28a13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 18:46:18 -0500
Subject: [PATCH 1429/2348] fix(schema+discriminator): support defining
 recursive embedded discriminators by passing document array schematype to
 discriminator

Fix #9600
---
 lib/schema.js                    |  3 +++
 test/model.discriminator.test.js | 40 ++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index 2dabeb61404..1dd9d9e704c 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -869,6 +869,9 @@ Object.defineProperty(Schema.prototype, 'base', {
 
 Schema.prototype.interpretAsType = function(path, obj, options) {
   if (obj instanceof SchemaType) {
+    if (obj.path === path) {
+      return obj;
+    }
     const clone = obj.clone();
     clone.path = path;
     return clone;
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index ad37c1ee187..02b46d5ac7f 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1645,4 +1645,44 @@ describe('model', function() {
     actions.discriminator('message', Message.schema);
     assert.ok(actions.schema.discriminators['message']);
   });
+
+  it('recursive embedded discriminator using schematype (gh-9600)', function() {
+    const contentSchema = new mongoose.Schema({}, { discriminatorKey: 'type' });
+    const nestedSchema = new mongoose.Schema({
+      body: {
+        children: [contentSchema]
+      }
+    });
+    const childrenArraySchema = nestedSchema.path('body.children');
+    childrenArraySchema.discriminator(
+      'container',
+      new mongoose.Schema({
+        body: { children: childrenArraySchema }
+      })
+    );
+    const Nested = mongoose.model('nested', nestedSchema);
+
+    const nestedDocument = new Nested({
+      body: {
+        children: [
+          { type: 'container', body: { children: [] } },
+          {
+            type: 'container',
+            body: {
+              children: [
+                {
+                  type: 'container',
+                  body: {
+                    children: [{ type: 'container', body: { children: [] } }]
+                  }
+                }
+              ]
+            }
+          }
+        ]
+      }
+    });
+
+    assert.deepEqual(nestedDocument.body.children[1].body.children[0].body.children[0].body.children, []);
+  });
 });

From b733c7b20022307b29e1c613646a37b05d4addac Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 19:12:00 -0500
Subject: [PATCH 1430/2348] fix(index.d.ts): add `Document#_id` so documents
 have an id by default

Fix #9632
Re: #9620
---
 index.d.ts                                     | 3 +++
 test/typescript/createBasicSchemaDefinition.ts | 1 +
 test/typescript/leanDocuments.ts               | 2 +-
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 85643c9a3c8..e58e63fe052 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -300,6 +300,9 @@ declare module "mongoose" {
   class Document {
     constructor(doc?: any);
 
+    /** This documents _id. */
+    _id: any;
+
     /** Don't run validation on this path or persist changes to this path. */
     $ignore(path: string): void;
 
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 7b8dbe17ff5..15bc92050e0 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -13,6 +13,7 @@ interface ITest extends Document {
 const Test = model<ITest>('Test', schema);
 
 const doc: ITest = new Test({ name: 'foo' });
+console.log(doc._id);
 doc.name = 'bar';
 
 doc.save().then((doc: ITest) => console.log(doc.name));
\ No newline at end of file
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index d86b9499ad9..9ea3d02fab9 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -7,7 +7,6 @@ class Subdoc extends Document {
 }
 
 interface ITest extends Document {
-  _id?: Types.ObjectId,
   name?: string;
   mixed?: any;
   subdoc?: Subdoc;
@@ -36,6 +35,7 @@ void async function main() {
   _doc.subdoc.toObject();
   _doc.name = 'test';
   _doc.mixed = 42;
+  console.log(_doc._id);
 
   const hydrated = Test.hydrate(_doc);
   await hydrated.save();

From 1bc2de836fdba733caf5518a5dca2340421ccdfc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 20:37:11 -0500
Subject: [PATCH 1431/2348] fix(index.d.ts): make it possible to use
 `LeanDocument` with arrays

Re: #9620
---
 index.d.ts                       | 7 ++++++-
 test/typescript/leanDocuments.ts | 7 +++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e58e63fe052..0cf295bc366 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1766,7 +1766,7 @@ declare module "mongoose" {
     j(val: boolean | null): this;
 
     /** Sets the lean option. */
-    lean(val?: boolean | any): Query<LeanDocument<DocType>, DocType>;
+    lean(val?: boolean | any): Query<LeanDocumentOrArray<ResultType>, DocType>;
 
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
@@ -2014,6 +2014,11 @@ declare module "mongoose" {
 
   export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
 
+  export type LeanDocumentOrArray<T> = 0 extends (1 & T) ? T :
+    T extends unknown[] ? LeanDocument<T[number]>[] :
+    T extends Document ? LeanDocument<T> :
+    T;
+
   class QueryCursor<DocType extends Document> extends stream.Readable {
     /**
      * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 9ea3d02fab9..e22ad4551b4 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document, Types } from 'mongoose';
+import { Schema, model, Document, LeanDocument } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
@@ -28,7 +28,7 @@ void async function main() {
   const pojo = doc.toObject();
   await pojo.save();
 
-  const _doc = await Test.findOne().lean();
+  const _doc: LeanDocument<ITest> = await Test.findOne().lean();
   await _doc.save();
 
   _doc.testMethod();
@@ -39,4 +39,7 @@ void async function main() {
 
   const hydrated = Test.hydrate(_doc);
   await hydrated.save();
+
+  const _docs: LeanDocument<ITest>[] = await Test.find().lean();
+  _docs[0].mixed = 42;
 }();
\ No newline at end of file

From f6ee4403742b4c643385700bd8ae83d00f77ab26 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Dec 2020 20:55:40 -0500
Subject: [PATCH 1432/2348] test: clean up a few issues with tests re: #9618

---
 index.d.ts                     | 2 +-
 test/typescript/aggregate.ts   | 1 -
 test/typescript/create.ts      | 1 -
 test/typescript/middleware.ts  | 1 -
 test/typescript/queries.ts     | 1 -
 test/typescript/querycursor.ts | 1 -
 6 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 0cf295bc366..e1420b97681 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -301,7 +301,7 @@ declare module "mongoose" {
     constructor(doc?: any);
 
     /** This documents _id. */
-    _id: any;
+    _id?: any;
 
     /** Don't run validation on this path or persist changes to this path. */
     $ignore(path: string): void;
diff --git a/test/typescript/aggregate.ts b/test/typescript/aggregate.ts
index b0d6da9eca0..9bcc1d12224 100644
--- a/test/typescript/aggregate.ts
+++ b/test/typescript/aggregate.ts
@@ -3,7 +3,6 @@ import { Schema, model, Document, Types } from 'mongoose';
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 interface ITest extends Document {
-  _id?: Types.ObjectId,
   name?: string;
 }
 
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
index edbdce4e83d..3a2f4d130fb 100644
--- a/test/typescript/create.ts
+++ b/test/typescript/create.ts
@@ -3,7 +3,6 @@ import { Schema, model, Document, Types } from 'mongoose';
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 interface ITest extends Document {
-  _id?: Types.ObjectId,
   name?: string;
 }
 
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index 00d29460c71..c39d1e068d5 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -19,7 +19,6 @@ schema.post<Aggregate<any>>('aggregate', async function(res: Array<any>) {
 });
 
 interface ITest extends Document {
-  _id?: Types.ObjectId,
   name?: string;
 }
 
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 72ed8fd9e29..bafbef1f542 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -3,7 +3,6 @@ import { Schema, model, Document, Types } from 'mongoose';
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 interface ITest extends Document {
-  _id?: Types.ObjectId,
   name?: string;
   age?: number;
 }
diff --git a/test/typescript/querycursor.ts b/test/typescript/querycursor.ts
index ff80c6f14a7..2592bf98e68 100644
--- a/test/typescript/querycursor.ts
+++ b/test/typescript/querycursor.ts
@@ -3,7 +3,6 @@ import { Schema, model, Document, Types } from 'mongoose';
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 interface ITest extends Document {
-  _id?: Types.ObjectId,
   name?: string;
 }
 

From 1956305dcedd0287521da230b7896bdeaf838527 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 3 Dec 2020 06:02:48 +0200
Subject: [PATCH 1433/2348] test(document): repro #9633

---
 test/document.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 25fbf58222a..b0bfabeb0fb 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9767,4 +9767,25 @@ describe('document', function() {
     const person = new Person({ items: undefined, email: 'test@gmail.com' });
     assert.equal(person.email, 'test@gmail.com');
   });
+
+  it('passes document to `default` functions (gh-9633)', function() {
+    let documentFromDefault;
+    const userSchema = new Schema({
+      name: { type: String },
+      age: {
+        type: Number,
+        default: function(doc) {
+          documentFromDefault = doc;
+        }
+      }
+
+    });
+
+    const User = db.model('User', userSchema);
+
+    const user = new User({ name: 'Hafez' });
+
+    assert.ok(documentFromDefault === user);
+    assert.equal(documentFromDefault.name, 'Hafez');
+  });
 });

From 3e7a528cbce7eb51876bfecb576692a2d66ca13a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 3 Dec 2020 06:03:12 +0200
Subject: [PATCH 1434/2348] enhancement(schemaType): pass documents to default
 functions as the first argument

---
 lib/schematype.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index 3cd297c46f2..faa482d9c86 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1028,7 +1028,7 @@ SchemaType.prototype.ref = function(ref) {
 
 SchemaType.prototype.getDefault = function(scope, init) {
   let ret = typeof this.defaultValue === 'function'
-    ? this.defaultValue.call(scope)
+    ? this.defaultValue.call(scope, scope)
     : this.defaultValue;
 
   if (ret !== null && ret !== undefined) {

From 3e5340a1d79c8672dc52e977091c242db3006ba4 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 3 Dec 2020 06:33:30 +0200
Subject: [PATCH 1435/2348] fix(types): add collectionName to Collection

---
 index.d.ts                    |  4 ++++
 test/typescript/collection.ts | 12 ++++++++++++
 test/typescript/main.test.js  |  8 ++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 test/typescript/collection.ts

diff --git a/index.d.ts b/index.d.ts
index e1420b97681..b01274aeda6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -294,7 +294,11 @@ declare module "mongoose" {
   }
 
   class Collection {
+    /**The name of the collection */
     name: string;
+    
+    /**The name of the collection */
+    collectionName: string;
   }
 
   class Document {
diff --git a/test/typescript/collection.ts b/test/typescript/collection.ts
new file mode 100644
index 00000000000..fd15e22fbad
--- /dev/null
+++ b/test/typescript/collection.ts
@@ -0,0 +1,12 @@
+import { Schema, model, Document } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITest extends Document {
+  name?: string;
+  age?: number;
+}
+
+const Test = model<ITest>('Test', schema);
+
+Test.collection.collectionName;
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 407f8f1e6b8..10d7b804c75 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -156,6 +156,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('collection', function() {
+    const errors = runTest('collection.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {

From d3f93b86c2c2c05e39a8a46b9d2276240bee5e38 Mon Sep 17 00:00:00 2001
From: saifalsabe <saif.alsabe@gmail.com>
Date: Thu, 3 Dec 2020 00:52:21 -0500
Subject: [PATCH 1436/2348] added missing custom error messages

---
 index.d.ts | 48 ++++++++++++++++++++++++------------------------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e1420b97681..dd5b3152c46 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -124,7 +124,7 @@ declare module "mongoose" {
 
   type Mongoose = typeof mongoose;
 
-  interface ClientSession extends mongodb.ClientSession {}
+  interface ClientSession extends mongodb.ClientSession { }
 
   interface ConnectOptions extends mongodb.MongoClientOptions {
     /** Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection. */
@@ -1203,7 +1203,7 @@ declare module "mongoose" {
      * Determines whether a type set to a POJO becomes
      * a Mixed path or a Subdocument (defaults to true).
      */
-    typePojoToMixed?:boolean;
+    typePojoToMixed?: boolean;
   }
 
   interface SchemaTimestampsConfig {
@@ -1219,7 +1219,7 @@ declare module "mongoose" {
     alias?: string;
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    validate?: RegExp | [RegExp, string] | Function;
+    validate?: RegExp | [RegExp, string] | Function | [Function | string];
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
     cast?: string;
@@ -1229,7 +1229,7 @@ declare module "mongoose" {
      * path cannot be set to a nullish value. If a function, Mongoose calls the
      * function and only checks for nullish values if the function returns a truthy value.
      */
-    required?: boolean | (() => boolean);
+    required?: boolean | (() => boolean) | [boolean, string];
 
     /**
      * The default value for this path. If a function, Mongoose executes the function
@@ -1332,10 +1332,10 @@ declare module "mongoose" {
     uppercase?: boolean;
 
     /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at least the given number. */
-    minlength?: number;
+    minlength?: number | [number, string];
 
     /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at most the given number. */
-    maxlength?: number;
+    maxlength?: number | [number, string];
   }
 
   interface IndexOptions {
@@ -1581,7 +1581,7 @@ declare module "mongoose" {
 
     // var objectId: mongoose.Types.ObjectId should reference mongodb.ObjectID not
     //   the ObjectIdConstructor, so we add the interface below
-    interface ObjectId extends mongodb.ObjectID {}
+    interface ObjectId extends mongodb.ObjectID { }
 
     class Subdocument extends Document {
       $isSingleNested: true;
@@ -1709,7 +1709,7 @@ declare module "mongoose" {
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
     findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
-    
+
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
     findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
@@ -1977,22 +1977,22 @@ declare module "mongoose" {
 
   export type FilterQuery<T> = {
     [P in keyof T]?: P extends '_id'
-      ? [Extract<T[P], mongodb.ObjectId>] extends [never]
-        ? mongodb.Condition<T[P]>
-        : mongodb.Condition<T[P] | string | { _id: mongodb.ObjectId }>
-      : [Extract<T[P], mongodb.ObjectId>] extends [never]
-      ? mongodb.Condition<T[P]>
-      : mongodb.Condition<T[P] | string>;
+    ? [Extract<T[P], mongodb.ObjectId>] extends [never]
+    ? mongodb.Condition<T[P]>
+    : mongodb.Condition<T[P] | string | { _id: mongodb.ObjectId }>
+    : [Extract<T[P], mongodb.ObjectId>] extends [never]
+    ? mongodb.Condition<T[P]>
+    : mongodb.Condition<T[P] | string>;
   } &
     mongodb.RootQuerySelector<T>;
-  
+
   export type UpdateQuery<T> = mongodb.UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;
 
   type FunctionPropertyNames<T> = {
     // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
-    [K in keyof T]: 0 extends (1 & T[K]) ? never : (T[K] extends Function ? K : never) 
+    [K in keyof T]: 0 extends (1 & T[K]) ? never : (T[K] extends Function ? K : never)
   }[keyof T];
 
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
@@ -2006,10 +2006,10 @@ declare module "mongoose" {
 
   export type _LeanDocument<T> = {
     [K in keyof T]:
-      0 extends (1 & T[K]) ? T[K] : // any
-      T[K] extends unknown[] ? LeanType<T[K][number]>[] : // Array
-      T[K] extends Document ? LeanDocument<T[K]> : // Subdocument
-      T[K];
+    0 extends (1 & T[K]) ? T[K] : // any
+    T[K] extends unknown[] ? LeanType<T[K][number]>[] : // Array
+    T[K] extends Document ? LeanDocument<T[K]> : // Subdocument
+    T[K];
   };
 
   export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
@@ -2246,7 +2246,7 @@ declare module "mongoose" {
       type?: string): this;
   }
 
-  class NativeError extends global.Error {}
+  class NativeError extends global.Error { }
   type CallbackError = NativeError | null;
 
   class Error extends global.Error {
@@ -2324,10 +2324,10 @@ declare module "mongoose" {
 
     export class ValidationError extends Error {
       name: 'ValidationError';
-  
-      errors: {[path: string]: ValidatorError | CastError};
+
+      errors: { [path: string]: ValidatorError | CastError };
     }
-  
+
     export class ValidatorError extends Error {
       name: 'ValidatorError';
       properties: {

From e39d407a33918c497fe23a2ace3f588d987df31b Mon Sep 17 00:00:00 2001
From: saifalsabe <saif.alsabe@gmail.com>
Date: Thu, 3 Dec 2020 01:27:22 -0500
Subject: [PATCH 1437/2348] added missing custom error messages

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index dd5b3152c46..c20deb8bcae 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1219,7 +1219,7 @@ declare module "mongoose" {
     alias?: string;
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    validate?: RegExp | [RegExp, string] | Function | [Function | string];
+    validate?: RegExp | [RegExp, string] | Function | [Function , string];
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
     cast?: string;

From 686155310efbb963c12c620e484a725734bf12c2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 3 Dec 2020 11:07:16 +0200
Subject: [PATCH 1438/2348] types(collection): make mongoose inherit from
 mongodb collection

---
 index.d.ts                     | 44 ++++++++++++++++++++++++++++++----
 test/typescript/collection.ts  |  7 +++++-
 test/typescript/main.test.js   |  6 +----
 test/typescript/ts.config.json |  9 +++++++
 4 files changed, 55 insertions(+), 11 deletions(-)
 create mode 100644 test/typescript/ts.config.json

diff --git a/index.d.ts b/index.d.ts
index b01274aeda6..d2b313c3560 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -293,12 +293,46 @@ declare module "mongoose" {
     watch(pipeline?: Array<any>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
   }
 
-  class Collection {
-    /**The name of the collection */
-    name: string;
-    
-    /**The name of the collection */
+   /*
+   * section collection.js
+   * http://mongoosejs.com/docs/api.html#collection-js
+   */
+  interface CollectionBase extends mongodb.Collection {
+    /*
+      * Abstract methods. Some of these are already defined on the
+      * mongodb.Collection interface so they've been commented out.
+      */
+    ensureIndex(...args: any[]): any;
+    findAndModify(...args: any[]): any;
+    getIndexes(...args: any[]): any;
+
+    /** The collection name */
     collectionName: string;
+    /** The Connection instance */
+    conn: Connection;
+    /** The collection name */
+    name: string;
+  }
+
+  /*
+   * section drivers/node-mongodb-native/collection.js
+   * http://mongoosejs.com/docs/api.html#drivers-node-mongodb-native-collection-js
+   */
+  let Collection: Collection;
+  interface Collection extends CollectionBase {
+    /**
+     * Collection constructor
+     * @param name name of the collection
+     * @param conn A MongooseConnection instance
+     * @param opts optional collection options
+     */
+    new(name: string, conn: Connection, opts?: any): Collection;
+    /** Formatter for debug print args */
+    $format(arg: any): string;
+    /** Debug print helper */
+    $print(name: any, i: any, args: any[]): void;
+    /** Retrieves information about this collections indexes. */
+    getIndexes(): any;
   }
 
   class Document {
diff --git a/test/typescript/collection.ts b/test/typescript/collection.ts
index fd15e22fbad..323bb08c719 100644
--- a/test/typescript/collection.ts
+++ b/test/typescript/collection.ts
@@ -9,4 +9,9 @@ interface ITest extends Document {
 
 const Test = model<ITest>('Test', schema);
 
-Test.collection.collectionName;
\ No newline at end of file
+Test.collection.collectionName;
+Test.collection.findOne({})
+Test.collection.findOneAndDelete({})
+Test.collection.ensureIndex()
+Test.collection.findAndModify()
+Test.collection.getIndexes()
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 10d7b804c75..9122ba1279e 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -3,11 +3,7 @@
 const assert = require('assert');
 const typescript = require('typescript');
 
-const tsconfig = {
-  allowSyntheticDefaultImports: true,
-  esModuleInterop: true,
-  outDir: `${__dirname}/dist`
-};
+const tsconfig = require('./ts.config.json');
 
 describe('typescript syntax', function() {
   this.timeout(5000);
diff --git a/test/typescript/ts.config.json b/test/typescript/ts.config.json
new file mode 100644
index 00000000000..e72f21108e7
--- /dev/null
+++ b/test/typescript/ts.config.json
@@ -0,0 +1,9 @@
+{
+  "allowSyntheticDefaultImports": true,
+  "esModuleInterop": true,
+  "outDir": "test/dist",
+  "include": [
+    "./**/*.ts",
+    "../../index.d.ts"
+  ]
+}
\ No newline at end of file

From b4a2fd952d669ba3e43753c8ac8eda062d0c3d83 Mon Sep 17 00:00:00 2001
From: Vladimir Metelitsa <green.cat@me.com>
Date: Thu, 3 Dec 2020 10:55:19 +0100
Subject: [PATCH 1439/2348] fix(index.d.ts): allows sub-documents in schema

Fixes #9631
---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e1420b97681..3a51348fc33 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1047,7 +1047,7 @@ declare module "mongoose" {
   }
 
   interface SchemaDefinition {
-    [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[];
+    [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[] | SchemaDefinition | SchemaDefinition[];
   }
 
   interface SchemaOptions {
@@ -2349,4 +2349,4 @@ declare module "mongoose" {
       modifiedPaths: Array<string>;
     }
   }
-}
\ No newline at end of file
+}

From 8440783a9978ff6ed3ef13d18ed2785db100a60f Mon Sep 17 00:00:00 2001
From: Vladimir Metelitsa <green.cat@me.com>
Date: Thu, 3 Dec 2020 10:58:23 +0100
Subject: [PATCH 1440/2348] Updates types test for #9631

---
 test/typescript/createBasicSchemaDefinition.ts | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 15bc92050e0..812b479cb90 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -2,12 +2,16 @@ import { Schema, model, Document } from 'mongoose';
 
 const schema: Schema = new Schema({
   name: { type: 'String' },
-  tags: [String]
+  tags: [String],
+  author: { name: String },
+  followers: [{ name: String }]
 }, { collection: 'mytest', versionKey: '_version' });
 
 interface ITest extends Document {
   name?: string;
   tags?: string[];
+  authors?: { name: string };
+  followers?: { name: string }[];
 }
 
 const Test = model<ITest>('Test', schema);
@@ -16,4 +20,4 @@ const doc: ITest = new Test({ name: 'foo' });
 console.log(doc._id);
 doc.name = 'bar';
 
-doc.save().then((doc: ITest) => console.log(doc.name));
\ No newline at end of file
+doc.save().then((doc: ITest) => console.log(doc.name));

From e9b8e3965a787fa94548d7439cabb59af6fd00ec Mon Sep 17 00:00:00 2001
From: Vladimir Metelitsa <green.cat@me.com>
Date: Thu, 3 Dec 2020 11:28:04 +0100
Subject: [PATCH 1441/2348] Fixes small typo

---
 test/typescript/createBasicSchemaDefinition.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 812b479cb90..1d7b094e0d7 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -10,7 +10,7 @@ const schema: Schema = new Schema({
 interface ITest extends Document {
   name?: string;
   tags?: string[];
-  authors?: { name: string };
+  author?: { name: string };
   followers?: { name: string }[];
 }
 

From a7f7b7696351508f64e2017b8cb47cb9a34c26b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 11:02:28 -0500
Subject: [PATCH 1442/2348] fix: quick fix re: #9637

---
 index.d.ts                | 11 +++++++++++
 test/typescript/global.ts |  1 +
 2 files changed, 12 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 59d38d782fc..ef1ec3882e5 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -4,6 +4,14 @@ declare module "mongoose" {
   import mongoose = require('mongoose');
   import stream = require('stream');
 
+  export enum ConnectionStates {
+    disconnected = 0,
+    connected = 1,
+    connecting = 2,
+    disconnecting = 3,
+    uninitialized = 99,
+  }
+
   /** The Mongoose Date [SchemaType](/docs/schematypes.html). */
   export type Date = Schema.Types.Date;
 
@@ -50,6 +58,9 @@ declare module "mongoose" {
   /** The various Mongoose SchemaTypes. */
   export var SchemaTypes: typeof Schema.Types;
 
+  /** Expose connection states for user-land */
+  export var STATES: typeof ConnectionStates;
+
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
   export function connect(uri: string, options: ConnectOptions, callback: (err: CallbackError) => void): void;
   export function connect(uri: string, callback: (err: CallbackError) => void): void;
diff --git a/test/typescript/global.ts b/test/typescript/global.ts
index 469afde2b30..6aae459ddaa 100644
--- a/test/typescript/global.ts
+++ b/test/typescript/global.ts
@@ -7,6 +7,7 @@ mongoose.get('useCreateIndex');
 const m: mongoose.Mongoose = new mongoose.Mongoose();
 
 m.set('useUnifiedTopology', true);
+m.STATES.connected;
 
 m.connect('mongodb://localhost:27017/test').then(() => {
   console.log('Connected!');

From 500c8ba1b922bab92c95280e7fb7a9828084c58e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 12:29:34 -0500
Subject: [PATCH 1443/2348] fix(index.d.ts): add `ModelUpdateOptions` as alias
 for `QueryOptions` for backwards compat

Re: #9637
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index ef1ec3882e5..f270a822de2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -867,6 +867,9 @@ declare module "mongoose" {
     writeConcern?: any;
   }
 
+  /** Alias for QueryOptions for backwards compatability. */
+  type ModelUpdateOptions = QueryOptions;
+
   interface SaveOptions {
     checkKeys?: boolean;
     validateBeforeSave?: boolean;

From 4b11cae828d817a754d2f56ee6ecedbe40658894 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 13:01:45 -0500
Subject: [PATCH 1444/2348] fix: handle ObjectId constructor for #9633

---
 lib/schematype.js | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index faa482d9c86..fdd9fc95e68 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1027,9 +1027,16 @@ SchemaType.prototype.ref = function(ref) {
  */
 
 SchemaType.prototype.getDefault = function(scope, init) {
-  let ret = typeof this.defaultValue === 'function'
-    ? this.defaultValue.call(scope, scope)
-    : this.defaultValue;
+  let ret;
+  if (typeof this.defaultValue === 'function') {
+    if (this.defaultValue === Date.now || this.defaultValue.name === 'ObjectID') {
+      ret = this.defaultValue.call(scope);
+    } else {
+      ret = this.defaultValue.call(scope, scope);
+    }
+  } else {
+    ret = this.defaultValue;
+  }
 
   if (ret !== null && ret !== undefined) {
     if (typeof ret === 'object' && (!this.options || !this.options.shared)) {

From e7494c92fae20075f29be7900bc9765f3d0fe852 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 14:21:42 -0500
Subject: [PATCH 1445/2348] fix: revert #9633 #9636

---
 lib/schematype.js     | 13 +++----------
 test/document.test.js |  2 +-
 2 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index fdd9fc95e68..3cd297c46f2 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1027,16 +1027,9 @@ SchemaType.prototype.ref = function(ref) {
  */
 
 SchemaType.prototype.getDefault = function(scope, init) {
-  let ret;
-  if (typeof this.defaultValue === 'function') {
-    if (this.defaultValue === Date.now || this.defaultValue.name === 'ObjectID') {
-      ret = this.defaultValue.call(scope);
-    } else {
-      ret = this.defaultValue.call(scope, scope);
-    }
-  } else {
-    ret = this.defaultValue;
-  }
+  let ret = typeof this.defaultValue === 'function'
+    ? this.defaultValue.call(scope)
+    : this.defaultValue;
 
   if (ret !== null && ret !== undefined) {
     if (typeof ret === 'object' && (!this.options || !this.options.shared)) {
diff --git a/test/document.test.js b/test/document.test.js
index b0bfabeb0fb..301cfab3f9f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9768,7 +9768,7 @@ describe('document', function() {
     assert.equal(person.email, 'test@gmail.com');
   });
 
-  it('passes document to `default` functions (gh-9633)', function() {
+  it.skip('passes document to `default` functions (gh-9633)', function() {
     let documentFromDefault;
     const userSchema = new Schema({
       name: { type: String },

From bac117e8062ef110da9938557df0c744e87d4a28 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 14:24:52 -0500
Subject: [PATCH 1446/2348] chore: release 5.11.3

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 456d3a6258d..a5ef77bd209 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.11.3 / 2020-12-03
+===================
+ * fix(schematype): pass document to default functions as first parameter #9636 #9633 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(index.d.ts): make Mongoose collection inherit MongoDB collection #9637 #9630 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(index.d.ts): add `Document#_id` so documents have an id by default #9632
+ * fix(index.d.ts): allow inline schema definitions for nested properties #9639 [Green-Cat](https://github.com/Green-Cat)
+ * fix(index.d.ts): add support for missing error message definitions #9638 [SaifAlsabe](https://github.com/SaifAlsabe)
+ * fix(schema+discriminator): support defining recursive embedded discriminators by passing document array schematype to discriminator #9600
+ * fix(index.d.ts): make it possible to use `LeanDocument` with arrays #9620
+ * fix(index.d.ts): add `ModelUpdateOptions` as alias for `QueryOptions` for backwards compat #9637
+
 5.11.2 / 2020-12-02
 ===================
  * fix(index.d.ts): add missing query options and model `findById()` function #9626 #9620
diff --git a/package.json b/package.json
index 6c222f7f501..be1c9181e79 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.2",
+  "version": "5.11.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 756750ef03859db46d747a7b6ab2f6d1afd4451d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 14:28:00 -0500
Subject: [PATCH 1447/2348] chore: remove reverted change from changelog

---
 History.md | 1 -
 1 file changed, 1 deletion(-)

diff --git a/History.md b/History.md
index a5ef77bd209..b455cbd4257 100644
--- a/History.md
+++ b/History.md
@@ -1,6 +1,5 @@
 5.11.3 / 2020-12-03
 ===================
- * fix(schematype): pass document to default functions as first parameter #9636 #9633 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
  * fix(index.d.ts): make Mongoose collection inherit MongoDB collection #9637 #9630 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
  * fix(index.d.ts): add `Document#_id` so documents have an id by default #9632
  * fix(index.d.ts): allow inline schema definitions for nested properties #9639 [Green-Cat](https://github.com/Green-Cat)

From 6afb5240a0620398f9c8c301e95099055138c26f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 16:23:17 -0500
Subject: [PATCH 1448/2348] fix(index.d.ts): add missing `session` option to
 `SaveOptions`

Fix #9642
---
 index.d.ts | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index f270a822de2..ebd12a19aa7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -872,13 +872,14 @@ declare module "mongoose" {
 
   interface SaveOptions {
     checkKeys?: boolean;
+    j?: boolean;
+    safe?: boolean | WriteConcern;
+    session?: ClientSession | null;
+    timestamps?: boolean;
     validateBeforeSave?: boolean;
     validateModifiedOnly?: boolean;
-    timestamps?: boolean;
-    j?: boolean;
     w?: number | string;
     wtimeout?: number;
-    safe?: boolean | WriteConcern;
   }
 
   interface WriteConcern {

From 17e64145e03b0b910584d6368e756c748c7388ae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 16:32:10 -0500
Subject: [PATCH 1449/2348] fix(index.d.ts): add missing `Connection#db`
 property

Fix #9643
---
 index.d.ts                    | 3 +++
 test/typescript/connection.ts | 4 +++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index ebd12a19aa7..d63224259d3 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -171,6 +171,9 @@ declare module "mongoose" {
     /** A hash of the global options that are associated with this connection */
     config: any;
 
+    /** The mongodb.Db instance, set when the connection is opened */
+    db: mongodb.Db;
+
     /**
      * Helper for `createCollection()`. Will explicitly create the given collection
      * with specified options. Used to create [capped collections](https://docs.mongodb.com/manual/core/capped-collections/)
diff --git a/test/typescript/connection.ts b/test/typescript/connection.ts
index 6d16fac8afd..7e35559014c 100644
--- a/test/typescript/connection.ts
+++ b/test/typescript/connection.ts
@@ -10,4 +10,6 @@ createConnection('mongodb://localhost:27017/test', { useNewUrlParser: true }).th
   conn.host;
 });
 
-createConnection('mongodb://localhost:27017/test').close();
\ No newline at end of file
+createConnection('mongodb://localhost:27017/test').close();
+
+conn.db.collection('Test').findOne({ name: String }).then(doc => console.log(doc));
\ No newline at end of file

From 68d90c0a7ec1f1d2fd309a8e734f8a4f348d425d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Dec 2020 16:37:52 -0500
Subject: [PATCH 1450/2348] test: fix tests re: #9639

---
 test/typescript/main.test.js | 3 +--
 test/typescript/maps.ts      | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 23f9d1a483e..78078bd56bd 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -37,8 +37,7 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 1);
-    assert.ok(errors[0].messageText.messageText.includes('not assignable'), errors[0].messageText.messageText);
+    assert.equal(errors.length, 0);
   });
 
   it('subdocuments', function() {
diff --git a/test/typescript/maps.ts b/test/typescript/maps.ts
index 59eaf591daa..fe8c3a0910a 100644
--- a/test/typescript/maps.ts
+++ b/test/typescript/maps.ts
@@ -13,7 +13,7 @@ const schema: Schema = new Schema({
     type: Map,
     of: {
       type: Number,
-      max: 'not a number'
+      max: 44
     }
   }
 });

From 4effd88a3d7078562cc4205e46b7352e73f29feb Mon Sep 17 00:00:00 2001
From: CatsMiaow <infiltrator@naver.com>
Date: Fri, 4 Dec 2020 14:36:44 +0900
Subject: [PATCH 1451/2348] fix(index.d.ts): order when cb is optional in
 method

---
 index.d.ts | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index d63224259d3..dc04e15b292 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -263,7 +263,7 @@ declare module "mongoose" {
 
     /**
      * Connection ready state
-     * 
+     *
      * - 0 = disconnected
      * - 1 = connected
      * - 2 = connecting
@@ -415,12 +415,12 @@ declare module "mongoose" {
     db: Connection;
 
     /** Removes this document from the db. */
-    delete(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
     delete(options?: QueryOptions): Query<any, this>;
+    delete(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Removes this document from the db. */
-    deleteOne(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
     deleteOne(options?: QueryOptions): Query<any, this>;
+    deleteOne(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Takes a populated field and returns it to its unpopulated state. */
     depopulate(path: string): this;
@@ -528,8 +528,8 @@ declare module "mongoose" {
     populated(path: string): any;
 
     /** Removes this document from the db. */
-    remove(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
     remove(options?: QueryOptions): Query<any, this>;
+    remove(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Sends a replaceOne command with this document `_id` as the query selector. */
     replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, this>;
@@ -595,8 +595,8 @@ declare module "mongoose" {
      * if you use `create()`) because with `bulkWrite()` there is only one round
      * trip to MongoDB.
      */
-    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: any, res: mongodb.BulkWriteOpResultObject) => void): void;
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions): Promise<mongodb.BulkWriteOpResultObject>;
+    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: any, res: mongodb.BulkWriteOpResultObject) => void): void;
 
     /** Collection the model uses. */
     collection: Collection;
@@ -1917,7 +1917,7 @@ declare module "mongoose" {
     /**
      * Declare and/or execute this query as a remove() operation. `remove()` is
      * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
-     * or [`deleteMany()`](#query_Query-deleteMany) instead. 
+     * or [`deleteMany()`](#query_Query-deleteMany) instead.
      */
     remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType>;
 
@@ -1950,7 +1950,7 @@ declare module "mongoose" {
     /**
      * Adds a `$set` to this query's update without changing the operation.
      * This is useful for query middleware so you can add an update regardless
-     * of whether you use `updateOne()`, `updateMany()`, `findOneAndUpdate()`, etc. 
+     * of whether you use `updateOne()`, `updateMany()`, `findOneAndUpdate()`, etc.
      */
     set(path: string, value: any): this;
 

From c7f657ff4caae62be640a5fa949f2551cfb6a16b Mon Sep 17 00:00:00 2001
From: sayan <sayan@email.com>
Date: Fri, 4 Dec 2020 20:36:41 +0530
Subject: [PATCH 1452/2348] fix(index.d.ts): add `Document#__v` so documents
 have an Version by default

---
 index.d.ts                                     | 3 +++
 test/typescript/createBasicSchemaDefinition.ts | 1 +
 2 files changed, 4 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index dc04e15b292..251405cb5b6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -355,6 +355,9 @@ declare module "mongoose" {
     /** This documents _id. */
     _id?: any;
 
+    /** This documents __v. */
+    __v?: number;
+
     /** Don't run validation on this path or persist changes to this path. */
     $ignore(path: string): void;
 
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 1d7b094e0d7..6c5e87c2b83 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -18,6 +18,7 @@ const Test = model<ITest>('Test', schema);
 
 const doc: ITest = new Test({ name: 'foo' });
 console.log(doc._id);
+console.log(doc.__v);
 doc.name = 'bar';
 
 doc.save().then((doc: ITest) => console.log(doc.name));

From 6b08c9a4a5fd9c2089639fd22e14be0380f28a7e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 11:01:51 -0500
Subject: [PATCH 1453/2348] test: add coverage for #9644

---
 package.json                 |  2 +-
 test/typescript/main.test.js |  8 ++++++++
 test/typescript/models.ts    | 16 ++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/models.ts

diff --git a/package.json b/package.json
index be1c9181e79..8a8cfd5ac25 100644
--- a/package.json
+++ b/package.json
@@ -76,7 +76,7 @@
     "prepublishOnly": "npm run build-browser",
     "release": "git pull && git push origin master --tags && npm publish",
     "release-legacy": "git pull origin 4.x && git push origin 4.x --tags && npm publish --tag legacy",
-    "test": "mocha --exit",
+    "test": "mocha --exit ./test/*.test.js ./test/typescript/main.test.js",
     "test-cov": "nyc --reporter=html --reporter=text npm test"
   },
   "main": "./index.js",
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 78078bd56bd..7bd4dd82de4 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -158,6 +158,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('models', function() {
+    const errors = runTest('models.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
new file mode 100644
index 00000000000..8d7bddc99f8
--- /dev/null
+++ b/test/typescript/models.ts
@@ -0,0 +1,16 @@
+import { Schema, Document, Model, connection } from 'mongoose';
+
+interface ITest extends Document {
+  foo: string;
+}
+
+const TestSchema = new Schema({
+  foo: { type: String, required: true }, 
+});
+
+const Test = connection.model<ITest>('Test', TestSchema);
+
+const bar = (SomeModel: Model<ITest>) => // <<<< error here
+  console.log(SomeModel);
+
+bar(Test);
\ No newline at end of file

From 3d01fe36c346715673a9bfb21d2f5740f36c22cf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 11:10:30 -0500
Subject: [PATCH 1454/2348] chore(travis): setup typescript tests in travis

---
 .travis.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index 687ab6ba270..ad98e77aa83 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,6 +13,8 @@ before_script:
   - export PATH=`pwd`/mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/:$PATH
   - sleep 2
   - mongod --version
+  - mkdir ./test/typescript/node_modules
+  - ln -s `pwd` ./test/typescript/node_modules/mongoose
 matrix:
   include:
     - name: "👕Linter"

From 84a194ba0bbeec92313d275b0381d969a7183e38 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 11:30:08 -0500
Subject: [PATCH 1455/2348] fix(index.d.ts): remove `Document#parent()` method
 because it conflicts with existing user code

Fix #9645
---
 index.d.ts                 | 3 ---
 test/typescript/queries.ts | 3 +++
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index dc04e15b292..e5b5e8a30ce 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -513,9 +513,6 @@ declare module "mongoose" {
      */
     overwrite(obj: DocumentDefinition<this>): this;
 
-    /** If this document is a subdocument or populated document, returns the document's parent. Returns `undefined` otherwise. */
-    parent(): Document | undefined;
-
     /**
      * Populates document references, executing the `callback` when complete.
      * If you want to use promises instead, use this function with
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index bafbef1f542..638e084c332 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -5,12 +5,15 @@ const schema: Schema = new Schema({ name: { type: 'String' } });
 interface ITest extends Document {
   name?: string;
   age?: number;
+  parent?: Types.ObjectId;
 }
 
 const Test = model<ITest>('Test', schema);
 
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
 
+Test.find({ parent: new Types.ObjectId('0'.repeat(24)) });
+
 Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => console.log(res));
 
 Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().

From c045c497b2b7e72273b851796269fe7da37a8adc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 11:41:55 -0500
Subject: [PATCH 1456/2348] fix(index.d.ts): correct callback result types for
 `find()`, `findOne()`, `findById()`

Fix #9648
---
 index.d.ts                 | 18 +++++++++---------
 test/typescript/queries.ts |  8 ++++++++
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c768e8e190e..e94bf61925e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -666,10 +666,10 @@ declare module "mongoose" {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<T | null, T>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<T | null, T>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
@@ -754,9 +754,9 @@ declare module "mongoose" {
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, count: number) => void): Query<Array<T>, T>;
-    find(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, count: number) => void): Query<Array<T>, T>;
+    find(callback?: (err: any, docs: T[]) => void): Query<Array<T>, T>;
+    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
@@ -1753,12 +1753,12 @@ declare module "mongoose" {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
-    find(filter: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<DocType>, DocType>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<Array<DocType>, DocType>;
+    find(callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType>;
+    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): Query<Array<DocType>, DocType>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
-    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, count: number) => void): Query<DocType | null, DocType>;
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 638e084c332..cbd0cc47d51 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -16,6 +16,14 @@ Test.find({ parent: new Types.ObjectId('0'.repeat(24)) });
 
 Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => console.log(res));
 
+Test.find({ name: 'test' }, (err: Error, docs: ITest[]) => {
+  console.log(!!err, docs[0].age);
+});
+
+Test.findOne({ name: 'test' }, (err: Error, doc: ITest) => {
+  console.log(!!err, doc.age);
+});
+
 Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().
   then((res: Array<ITest>) => console.log(res[0].name));
 

From 7fae1bbce9fcf4b524f4db1a8a8995950c26456e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 11:53:04 -0500
Subject: [PATCH 1457/2348] fix(index.d.ts): use DocumentDefinition for
 `FilterQuery`

Fix #9649
---
 index.d.ts | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index e94bf61925e..f0f6949c3db 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2031,7 +2031,7 @@ declare module "mongoose" {
     wtimeout(ms: number): this;
   }
 
-  export type FilterQuery<T> = {
+  type _FilterQuery<T> = {
     [P in keyof T]?: P extends '_id'
     ? [Extract<T[P], mongodb.ObjectId>] extends [never]
     ? mongodb.Condition<T[P]>
@@ -2042,6 +2042,8 @@ declare module "mongoose" {
   } &
     mongodb.RootQuerySelector<T>;
 
+  export type FilterQuery<T> = _FilterQuery<DocumentDefinition<T>>;
+
   export type UpdateQuery<T> = mongodb.UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
 
   export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;

From f8c5df31b9ca56bb7635825f43c3f57da12de60c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 12:00:26 -0500
Subject: [PATCH 1458/2348] fix(index.d.ts): add `Schema#paths`,
 `Schema#static(obj)`, `Embedded#schema`, `DocumentArray#schema`, make Schema
 inherit from EventEmitter

Fix #9650
---
 index.d.ts | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index f0f6949c3db..7dd4c00b234 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -702,6 +702,10 @@ declare module "mongoose" {
     listIndexes(callback: (err: CallbackError, res: Array<any>) => void): void;
     listIndexes(): Promise<Array<any>>;
 
+    /** The name of the model */
+    modelName: string;
+
+    /** Populates document references. */
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
       callback?: (err: any, res: T[]) => void): Promise<Array<T>>;
 
@@ -1001,7 +1005,7 @@ declare module "mongoose" {
     useProjection?: boolean;
   }
 
-  class Schema {
+  class Schema extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1051,6 +1055,11 @@ declare module "mongoose" {
     path(path: string): SchemaType;
     path(path: string, constructor: any): this;
 
+    /** Lists all paths and their type in the schema. */
+    paths: {
+      [key: string]: SchemaType;
+    }
+
     /** Returns the pathType of `path` for this schema. */
     pathType(path: string): string;
 
@@ -1091,6 +1100,7 @@ declare module "mongoose" {
 
     /** Adds static "class" methods to Models compiled from this schema. */
     static(name: string, fn: Function): this;
+    static(obj: { [name: string]: Function }): this;
 
     /** Object of currently defined statics on this schema. */
     statics: any;
@@ -1474,6 +1484,9 @@ declare module "mongoose" {
         static options: { castNonArrays: boolean; };
 
         discriminator(name: string, schema: Schema, tag?: string): any;
+
+        /** The schema used for documents in this array */
+        schema: Schema;
       }
 
       class Map extends SchemaType {
@@ -1511,6 +1524,9 @@ declare module "mongoose" {
       class Embedded extends SchemaType {
         /** This schema type's name, to defend against minifiers that mangle function names. */
         static schemaName: string;
+
+        /** The document's schema */
+        schema: Schema;
       }
 
       class String extends SchemaType {

From ef37e2d6106e7e9dd384794265af03bbdf274488 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 12:13:54 -0500
Subject: [PATCH 1459/2348] chore: release v5.11.4

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index b455cbd4257..cc9fbf9b469 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.11.4 / 2020-12-04
+===================
+ * fix(index.d.ts): add `Document#__v` so documents have a Version by default #9652 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): add missing `session` option to `SaveOptions` #9642
+ * fix(index.d.ts): add `Schema#paths`, `Schema#static(obj)`, `Embedded#schema`, `DocumentArray#schema`, make Schema inherit from EventEmitter #9650
+ * fix(index.d.ts): order when cb is optional in method #9647 [CatsMiaow](https://github.com/CatsMiaow)
+ * fix(index.d.ts): use DocumentDefinition for `FilterQuery` #9649
+ * fix(index.d.ts): correct callback result types for `find()`, `findOne()`, `findById()` #9648
+ * fix(index.d.ts): remove `Document#parent()` method because it conflicts with existing user code #9645
+ * fix(index.d.ts): add missing `Connection#db` property #9643
+ * test(typescript): add `tsconfig.json` file for intellisense #9611 [alecgibson](https://github.com/alecgibson)
+
 5.11.3 / 2020-12-03
 ===================
  * fix(index.d.ts): make Mongoose collection inherit MongoDB collection #9637 #9630 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
diff --git a/package.json b/package.json
index 8a8cfd5ac25..4bb69887bde 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.3",
+  "version": "5.11.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 060bfb7ad51344281a1d6a42cd148980b50a943c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 12:56:50 -0500
Subject: [PATCH 1460/2348] docs(compatibility): add MongoDB server 4.4 version
 compatibility

Fix #9641
---
 docs/compatibility.pug | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/compatibility.pug b/docs/compatibility.pug
index a6e5b942f86..1ce8f946aec 100644
--- a/docs/compatibility.pug
+++ b/docs/compatibility.pug
@@ -40,6 +40,7 @@ block content
     * MongoDB Server 3.6.x: mongoose `5.x`
     * MongoDB Server 4.0.x: mongoose `^5.2.0`
     * MongoDB Server 4.2.x: mongoose `^5.7.0`
+    * MongoDB Server 4.4.x: mongoose `^5.10.0`
 
     Note that Mongoose 5.x dropped support for all versions of MongoDB before
     3.0.0. If you need to use MongoDB 2.6 or older, use Mongoose 4.x.

From 8e00926ff95c6b0cb1b751dac9ede297d1490c5b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Dec 2020 12:57:15 -0500
Subject: [PATCH 1461/2348] docs(populate): remove `sort()` from `limit`
 example to avoid potential confusion

Fix #9584
---
 docs/populate.pug | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 2ad6b0c54eb..9ff769a0b54 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -296,8 +296,8 @@ block content
     <h3 id="limit-vs-perDocumentLimit"><a href="#limit-vs-perDocumentLimit">limit vs. perDocumentLimit</a></h3>
 
     Populate does support a `limit` option, however, it currently
-    does **not** limit on a per-document basis. For example, suppose
-    you have 2 stories:
+    does **not** limit on a per-document basis for backwards compatibility. For example,
+    suppose you have 2 stories:
 
     ```javascript
     Story.create([
@@ -310,12 +310,16 @@ block content
     would find that the 2nd story has 0 fans:
 
     ```javascript
-    const stories = Story.find().sort({ name: 1 }).populate({
+    const stories = Story.find().populate({
       path: 'fans',
       options: { limit: 2 }
     });
 
+    stories[0].name; // 'Casino Royale'
     stories[0].fans.length; // 2
+
+    // 2nd story has 0 fans!
+    stories[1].name; // 'Live and Let Die'
     stories[1].fans.length; // 0
     ```
 
@@ -324,17 +328,20 @@ block content
     `numDocuments * limit` as the limit. If you need the correct
     `limit`, you should use the `perDocumentLimit` option (new in Mongoose 5.9.0).
     Just keep in mind that `populate()` will execute a separate query
-    for each story.
+    for each story, which may cause `populate()` to be slower.
 
     ```javascript
-    const stories = await Story.find().sort({ name: 1 }).populate({
+    const stories = await Story.find().populate({
       path: 'fans',
       // Special option that tells Mongoose to execute a separate query
       // for each `story` to make sure we get 2 fans for each story.
       perDocumentLimit: 2
     });
 
+    stories[0].name; // 'Casino Royale'
     stories[0].fans.length; // 2
+
+    stories[1].name; // 'Live and Let Die'
     stories[1].fans.length; // 2
     ```
 

From f87e2c230dd48675b2562157003a6726dae91978 Mon Sep 17 00:00:00 2001
From: Sayan Saha <sayan@page2.page>
Date: Sat, 5 Dec 2020 01:54:12 +0530
Subject: [PATCH 1462/2348] fix(index.d.ts): add generic declaration for Schema

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 7dd4c00b234..29598acf7e8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1005,7 +1005,7 @@ declare module "mongoose" {
     useProjection?: boolean;
   }
 
-  class Schema extends events.EventEmitter {
+  class Schema<T = any> extends events.EventEmitter {
     /**
      * Create a new schema
      */

From eaa6e5bde6fe796591f5ff5c625070c5d3dd8f59 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 6 Dec 2020 06:48:13 +0200
Subject: [PATCH 1463/2348] types(base): add mongoose.models object re #9660

---
 index.d.ts              | 2 ++
 test/typescript/base.ts | 6 ++++++
 2 files changed, 8 insertions(+)
 create mode 100644 test/typescript/base.ts

diff --git a/index.d.ts b/index.d.ts
index 29598acf7e8..cfed6947bbb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -72,6 +72,8 @@ declare module "mongoose" {
   /** An array containing all connections associated with this Mongoose instance. */
   export var connections: Connection[];
 
+  /** An array containing all models associated with this Mongoose instance. */
+  export var models: { [index: string]: Model<any> };
   /** Creates a Connection instance. */
   export function createConnection(uri: string, options?: ConnectOptions): Connection & Promise<Connection>;
   export function createConnection(): Connection;
diff --git a/test/typescript/base.ts b/test/typescript/base.ts
new file mode 100644
index 00000000000..e952d82f96c
--- /dev/null
+++ b/test/typescript/base.ts
@@ -0,0 +1,6 @@
+import * as mongoose from 'mongoose'
+
+Object.values(mongoose.models).forEach(model=>{
+  model.modelName;
+  model.findOne()
+});
\ No newline at end of file

From 64a0ab3f0b313db53921823693d595842a201661 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 6 Dec 2020 06:48:24 +0200
Subject: [PATCH 1464/2348] test(types): repro #9660

---
 test/typescript/main.test.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 7bd4dd82de4..0b41c64eed7 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -7,6 +7,14 @@ const tsconfig = require('./tsconfig.json');
 describe('typescript syntax', function() {
   this.timeout(5000);
 
+  it('base', function() {
+    const errors = runTest('base.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
+
   it('create schema and model', function() {
     const errors = runTest('createBasicSchemaDefinition.ts');
     if (process.env.D && errors.length) {

From 9572e21d70871ba900f851285e33e3e650f0e086 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 6 Dec 2020 07:00:38 +0200
Subject: [PATCH 1465/2348] chore: remove duplicated ts.config.json

---
 test/typescript/ts.config.json | 9 ---------
 1 file changed, 9 deletions(-)
 delete mode 100644 test/typescript/ts.config.json

diff --git a/test/typescript/ts.config.json b/test/typescript/ts.config.json
deleted file mode 100644
index e72f21108e7..00000000000
--- a/test/typescript/ts.config.json
+++ /dev/null
@@ -1,9 +0,0 @@
-{
-  "allowSyntheticDefaultImports": true,
-  "esModuleInterop": true,
-  "outDir": "test/dist",
-  "include": [
-    "./**/*.ts",
-    "../../index.d.ts"
-  ]
-}
\ No newline at end of file

From 58d1c79a089f09a844d696a34c9f34b392542a84 Mon Sep 17 00:00:00 2001
From: Orgad Shaneh <orgad.shaneh@audiocodes.com>
Date: Sun, 6 Dec 2020 09:50:51 +0200
Subject: [PATCH 1466/2348] fix(index.d.ts): Change options in
 Connection#collection() to be optional

---
 index.d.ts                    | 2 +-
 test/typescript/connection.ts | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 29598acf7e8..03820491271 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -163,7 +163,7 @@ declare module "mongoose" {
     close(force?: boolean): Promise<void>;
 
     /** Retrieves a collection, creating it if not cached. */
-    collection(name: string, options: mongodb.CollectionCreateOptions): Collection;
+    collection(name: string, options?: mongodb.CollectionCreateOptions): Collection;
 
     /** A hash of the collections associated with this connection */
     collections: { [index: string]: Collection };
diff --git a/test/typescript/connection.ts b/test/typescript/connection.ts
index 7e35559014c..eb3b9095230 100644
--- a/test/typescript/connection.ts
+++ b/test/typescript/connection.ts
@@ -12,4 +12,5 @@ createConnection('mongodb://localhost:27017/test', { useNewUrlParser: true }).th
 
 createConnection('mongodb://localhost:27017/test').close();
 
-conn.db.collection('Test').findOne({ name: String }).then(doc => console.log(doc));
\ No newline at end of file
+conn.db.collection('Test').findOne({ name: String }).then(doc => console.log(doc));
+conn.collection('Test').findOne({ name: String }).then(doc => console.log(doc));

From a4c3325e2310da8638df6ef8f91f7920b89341fa Mon Sep 17 00:00:00 2001
From: Sayan Saha <sayan@page2.page>
Date: Sun, 6 Dec 2020 21:28:55 +0530
Subject: [PATCH 1467/2348] fix(index.ts): allow the next() argument to be
 optional

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 29598acf7e8..37e3cdc1e0c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1078,7 +1078,7 @@ declare module "mongoose" {
     post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;

From d4c17cef1ddfd952c2e6aa8809a95ede5e37dc13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 6 Dec 2020 11:16:02 -0500
Subject: [PATCH 1468/2348] fix(index.d.ts): improve support for strict null
 checks with `upsert` and `orFail()`

Fix #9654
---
 index.d.ts                       | 14 +++++++++++---
 test/typescript/connectSyntax.ts |  4 ++--
 test/typescript/create.ts        |  4 ++--
 test/typescript/docArray.ts      |  4 ++--
 test/typescript/leanDocuments.ts |  5 ++---
 test/typescript/main.test.js     |  3 +--
 test/typescript/queries.ts       |  3 ++-
 test/typescript/tsconfig.json    |  1 +
 8 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 29598acf7e8..b6a72247062 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -688,8 +688,10 @@ declare module "mongoose" {
     init(callback?: (err: any) => void): Promise<T>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
-    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T | InsertManyResult>;
-    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T> | InsertManyResult>;
+    insertMany(doc: T | DocumentDefinition<T>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
+    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T>;
+    insertMany(docs: Array<T | DocumentDefinition<T>>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
+    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T>>;
     insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions, callback?: (err: CallbackError, res: T | InsertManyResult) => void): void;
     insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<T> | InsertManyResult) => void): void;
 
@@ -769,6 +771,7 @@ declare module "mongoose" {
     findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
@@ -778,9 +781,11 @@ declare module "mongoose" {
     findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T>;
@@ -800,6 +805,7 @@ declare module "mongoose" {
     schema: Schema;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option. */
@@ -1783,12 +1789,14 @@ declare module "mongoose" {
     findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Specifies a `$geometry` condition */
@@ -1907,7 +1915,7 @@ declare module "mongoose" {
      * This is handy for integrating with async/await, because `orFail()` saves you
      * an extra `if` statement to check if no document was found.
      */
-    orFail(err?: NativeError | (() => NativeError)): this;
+    orFail(err?: NativeError | (() => NativeError)): Query<NonNullable<ResultType>, DocType>;
 
     /** Specifies a `$polygon` condition */
     polygon(...coordinatePairs: number[][]): this;
diff --git a/test/typescript/connectSyntax.ts b/test/typescript/connectSyntax.ts
index 513c38d460a..1b84311dd7e 100644
--- a/test/typescript/connectSyntax.ts
+++ b/test/typescript/connectSyntax.ts
@@ -9,6 +9,6 @@ connect('mongodb://localhost:27017/test', {
 }).then(mongoose => console.log(mongoose.connect));
 
 // Callback
-connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }, (err: Error) => {
-  console.log(err.stack);
+connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }, (err: Error | null) => {
+  console.log(err);
 });
\ No newline at end of file
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
index 3a2f4d130fb..65e57fc5533 100644
--- a/test/typescript/create.ts
+++ b/test/typescript/create.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document, Types } from 'mongoose';
+import { Schema, model, Document } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
@@ -17,4 +17,4 @@ Test.create({ name: 'test' }, { name: 'test2' }).then((doc: ITest) => console.lo
 Test.insertMany({ name: 'test' }).then((doc: ITest) => console.log(doc.name));
 Test.insertMany([{ name: 'test' }], { session: null }).then((docs: ITest[]) => console.log(docs[0].name));
 
-Test.create({ name: 'test' }, { validateBeforeSave: true }).then((doc: ITest) => console.log(doc.name));
\ No newline at end of file
+Test.create([{ name: 'test' }], { validateBeforeSave: true }).then((docs: ITest[]) => console.log(docs[0].name));
\ No newline at end of file
diff --git a/test/typescript/docArray.ts b/test/typescript/docArray.ts
index 24d31ee7434..f6122d0b23b 100644
--- a/test/typescript/docArray.ts
+++ b/test/typescript/docArray.ts
@@ -13,7 +13,7 @@ interface ITest extends Document {
 const Test = model<ITest>('Test', schema);
 
 void async function main() {
-  const doc: ITest = await Test.findOne();
+  const doc: ITest = await Test.findOne().orFail();
 
   doc.tags = new Types.DocumentArray<Subdoc>([]);
   doc.set('tags', []);
@@ -25,7 +25,7 @@ void async function main() {
 
   await doc.save();
 
-  const _doc: LeanDocument<ITest> = await Test.findOne().lean();
+  const _doc: LeanDocument<ITest> = await Test.findOne().orFail().lean();
   _doc.tags[0].name.substr(1);
   _doc.tags.create({ name: 'fail' });
 }();
\ No newline at end of file
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index e22ad4551b4..75d77d93ec5 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -18,7 +18,7 @@ schema.method('testMethod', () => 42);
 const Test = model<ITest>('Test', schema);
 
 void async function main() {
-  const doc: ITest = await Test.findOne();
+  const doc: ITest = await Test.findOne().orFail();
 
   doc.subdoc = new Subdoc({ name: 'test' });
   doc.id = 'Hello';
@@ -28,11 +28,10 @@ void async function main() {
   const pojo = doc.toObject();
   await pojo.save();
 
-  const _doc: LeanDocument<ITest> = await Test.findOne().lean();
+  const _doc: LeanDocument<ITest> = await Test.findOne().orFail().lean();
   await _doc.save();
 
   _doc.testMethod();
-  _doc.subdoc.toObject();
   _doc.name = 'test';
   _doc.mixed = 42;
   console.log(_doc._id);
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 7bd4dd82de4..bef2d0783bd 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -119,11 +119,10 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 4);
+    assert.equal(errors.length, 3);
     assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
     assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[1].messageText);
     assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[2].messageText);
-    assert.ok(errors[3].messageText.includes('Property \'toObject\' does not exist'), errors[3].messageText);
   });
 
   it('doc array', function() {
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index cbd0cc47d51..ca4d17a9f82 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -27,7 +27,7 @@ Test.findOne({ name: 'test' }, (err: Error, doc: ITest) => {
 Test.find({ name: { $gte: 'Test' } }, null, { collation: { locale: 'en-us' } }).exec().
   then((res: Array<ITest>) => console.log(res[0].name));
 
-Test.findOne().orFail(new Error('bar')).then((doc: ITest) => console.log('Found! ' + doc.name));
+Test.findOne().orFail(new Error('bar')).then((doc: ITest | null) => console.log('Found! ' + doc));
 
 Test.distinct('name').exec().then((res: Array<any>) => console.log(res[0]));
 
@@ -35,5 +35,6 @@ Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITe
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { $set: { name: 'test2' } }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest | null) => console.log(res));
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true }).then((res: ITest) => { res.name = 'test4' });
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
\ No newline at end of file
diff --git a/test/typescript/tsconfig.json b/test/typescript/tsconfig.json
index 0ebf21f8742..70ca16895b7 100644
--- a/test/typescript/tsconfig.json
+++ b/test/typescript/tsconfig.json
@@ -2,6 +2,7 @@
   "allowSyntheticDefaultImports": true,
   "esModuleInterop": true,
   "outDir": "test/dist",
+  "strictNullChecks": true,
   "include": [
     "./**/*.ts",
     "../../index.d.ts"

From eb0bae4567f54ef057b8be8bb8e73a5a9385650e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 6 Dec 2020 16:50:27 -0500
Subject: [PATCH 1469/2348] fix(index.d.ts): add missing types for hook
 functions

Fix #9653
---
 index.d.ts                   | 29 ++++++++++++++++++++++++++---
 test/typescript/main.test.js |  2 +-
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b6a72247062..7b48509c0e7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -880,9 +880,6 @@ declare module "mongoose" {
     writeConcern?: any;
   }
 
-  /** Alias for QueryOptions for backwards compatability. */
-  type ModelUpdateOptions = QueryOptions;
-
   interface SaveOptions {
     checkKeys?: boolean;
     j?: boolean;
@@ -2431,4 +2428,30 @@ declare module "mongoose" {
       modifiedPaths: Array<string>;
     }
   }
+
+  /** Deprecated types for backwards compatibility. */
+
+  /** Alias for QueryOptions for backwards compatability. */
+  type ModelUpdateOptions = QueryOptions;
+
+  /** Backwards support for DefinitelyTyped */
+  interface HookSyncCallback<T> {
+    (this: T, next: HookNextFunction, docs: any[]): Promise<any> | void;
+  }
+
+  interface HookAsyncCallback<T> {
+    (this: T, next: HookNextFunction, done: HookDoneFunction, docs: any[]): Promise<any> | void;
+  }
+
+  interface HookErrorCallback {
+    (error?: Error): any;
+  }
+
+  interface HookNextFunction {
+    (error?: Error): any;
+  }
+
+  interface HookDoneFunction {
+    (error?: Error): any;
+  }
 }
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index bef2d0783bd..052b200fa23 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -5,7 +5,7 @@ const typescript = require('typescript');
 const tsconfig = require('./tsconfig.json');
 
 describe('typescript syntax', function() {
-  this.timeout(5000);
+  this.timeout(10000);
 
   it('create schema and model', function() {
     const errors = runTest('createBasicSchemaDefinition.ts');

From c704fa6ff2bfad0a8666829ef865dc11bdc6b822 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 6 Dec 2020 17:36:42 -0500
Subject: [PATCH 1470/2348] fix(index.d.ts): add `id` to LeanDocuments in case
 it is defined in the user's schema

Fix #9657
---
 index.d.ts                       | 2 +-
 test/typescript/leanDocuments.ts | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 073859f9cbc..2148e09e7c9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2093,7 +2093,7 @@ declare module "mongoose" {
     T[K];
   };
 
-  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>;
+  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id'>>, FunctionPropertyNames<T>>;
 
   export type LeanDocumentOrArray<T> = 0 extends (1 & T) ? T :
     T extends unknown[] ? LeanDocument<T[number]>[] :
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 75d77d93ec5..38a818275ee 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -11,6 +11,7 @@ interface ITest extends Document {
   mixed?: any;
   subdoc?: Subdoc;
   testMethod: () => number;
+  id: string;
 }
 
 schema.method('testMethod', () => 42);
@@ -34,6 +35,7 @@ void async function main() {
   _doc.testMethod();
   _doc.name = 'test';
   _doc.mixed = 42;
+  _doc.id = 'test2';
   console.log(_doc._id);
 
   const hydrated = Test.hydrate(_doc);

From 9c0b97124033b74714b04df21f1e66478e788981 Mon Sep 17 00:00:00 2001
From: Alec Gibson <aleckgibson@gmail.com>
Date: Mon, 7 Dec 2020 09:37:01 +0000
Subject: [PATCH 1471/2348] fix(index.d.ts): Allow number for Schema expires

---
 index.d.ts                |  2 +-
 test/typescript/models.ts | 11 +++++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 2148e09e7c9..cc86c1c46ca 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1376,7 +1376,7 @@ declare module "mongoose" {
     max?: number | Date;
 
     /** Defines a TTL index on this path. Only allowed for dates. */
-    expires?: Date;
+    expires?: number | Date;
 
     /** If `true`, Mongoose will skip gathering indexes on subpaths. Only allowed for subdocuments and subdocument arrays. */
     excludeIndexes?: boolean;
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 8d7bddc99f8..19a211e9d9b 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -5,7 +5,7 @@ interface ITest extends Document {
 }
 
 const TestSchema = new Schema({
-  foo: { type: String, required: true }, 
+  foo: { type: String, required: true },
 });
 
 const Test = connection.model<ITest>('Test', TestSchema);
@@ -13,4 +13,11 @@ const Test = connection.model<ITest>('Test', TestSchema);
 const bar = (SomeModel: Model<ITest>) => // <<<< error here
   console.log(SomeModel);
 
-bar(Test);
\ No newline at end of file
+bar(Test);
+
+const ExpiresSchema = new Schema({
+  ttl: {
+    type: Date,
+    expires: 3600,
+  },
+});

From 8c3258771b4947bb3ce4a20561cc10327d7e5a3a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 12:22:37 -0500
Subject: [PATCH 1472/2348] fix(index.d.ts): support object syntax for
 `validate`

Fix #9667
---
 index.d.ts                                    | 21 ++++++++++++++++++-
 .../typescript/createBasicSchemaDefinition.ts |  6 ++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 2148e09e7c9..4c0caed8e5b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1290,7 +1290,7 @@ declare module "mongoose" {
     alias?: string;
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    validate?: RegExp | [RegExp, string] | Function | [Function , string];
+    validate?: RegExp | [RegExp, string] | Function | [Function , string] | ValidateOpts<T>;
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
     cast?: string;
@@ -1417,6 +1417,25 @@ declare module "mongoose" {
     unique?: boolean
   }
 
+  interface ValidateFn<T> {
+    (value: T): boolean;
+  }
+
+  interface LegacyAsyncValidateFn<T> {
+    (value: T, done: (result: boolean) => void): void;
+  }
+
+  interface AsyncValidateFn<T> {
+    (value: any): Promise<boolean>;
+  }
+
+  interface ValidateOpts<T> {
+    msg?: string;
+    message?: string;
+    type?: string;
+    validator: ValidateFn<T> | LegacyAsyncValidateFn<T> | AsyncValidateFn<T>;
+  }
+
   class VirtualType {
     /** Adds a custom getter to this virtual. */
     get(fn: Function): this;
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 6c5e87c2b83..37dcbc73bc1 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -4,6 +4,12 @@ const schema: Schema = new Schema({
   name: { type: 'String' },
   tags: [String],
   author: { name: String },
+  email: {
+    type: String,
+    validate: {
+      validator: v => v.includes('@')
+    }
+  },
   followers: [{ name: String }]
 }, { collection: 'mytest', versionKey: '_version' });
 

From 1dd526622d307c77512c1c6e7a6d5fa5d4355f39 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 12:40:34 -0500
Subject: [PATCH 1473/2348] fix(index.d.ts): add missing
 `VirtualType#applyGetters()` and `applySetters()`, `Schema#virtuals`,
 `Schema#childSchemas`, `Query#_mongooseOptions`

Fix #9658
---
 index.d.ts | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 67ce1abf43b..7719bc83beb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1019,9 +1019,19 @@ declare module "mongoose" {
     /** Adds key path / schema type pairs to this schema. */
     add(obj: SchemaDefinition | Schema, prefix?: string): this;
 
+    /**
+     * Array of child schemas (from document arrays and single nested subdocs)
+     * and their corresponding compiled models. Each element of the array is
+     * an object with 2 properties: `schema` and `model`.
+     */
+    childSchemas: { schema: Schema, model: any }[];
+
     /** Returns a copy of this schema */
     clone(): Schema;
 
+    /** Object containing discriminators defined on this schema */
+    discriminators?: { [name: string]: Schema };
+
     /** Iterates the schemas paths similar to Array#forEach. */
     eachPath(fn: (path: string, type: SchemaType) => void): this;
 
@@ -1113,6 +1123,9 @@ declare module "mongoose" {
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;
 
+    /** Object of currently defined virtuals on this schema */
+    virtuals: any;
+
     /** Returns the virtual type with the given `name`. */
     virtualpath(name: string): VirtualType | null;
   }
@@ -1437,6 +1450,11 @@ declare module "mongoose" {
   }
 
   class VirtualType {
+    /** Applies getters to `value`. */
+    applyGetters(value: any, doc: Document): any;
+    /** Applies setters to `value`. */
+    applySetters(value: any, doc: Document): any;
+
     /** Adds a custom getter to this virtual. */
     get(fn: Function): this;
     /** Adds a custom setter to this virtual. */
@@ -1691,6 +1709,8 @@ declare module "mongoose" {
   }
 
   interface Query<ResultType, DocType extends Document> {
+    _mongooseOptions: QueryOptions;
+
     exec(): Promise<ResultType>;
     exec(callback?: (err: CallbackError, res: ResultType) => void): void;
 

From 3254b03ce769fac8dc4635ce6fdb47e4b7231f44 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 12:45:40 -0500
Subject: [PATCH 1474/2348] fix(index.d.ts): allow definining arbitrary
 properties on SchemaTypeOpts for plugins like mongoose-autopopulate

Fix #9669
---
 index.d.ts                                     | 2 ++
 test/typescript/createBasicSchemaDefinition.ts | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 7719bc83beb..fe8a3f154a2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1420,6 +1420,8 @@ declare module "mongoose" {
 
     /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at most the given number. */
     maxlength?: number | [number, string];
+
+    [other: string]: any;
   }
 
   interface IndexOptions {
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 37dcbc73bc1..3ec8691befb 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -8,7 +8,8 @@ const schema: Schema = new Schema({
     type: String,
     validate: {
       validator: v => v.includes('@')
-    }
+    },
+    otherProperty: 42
   },
   followers: [{ name: String }]
 }, { collection: 'mytest', versionKey: '_version' });

From 8077d1c7c7d5f08d0510f074a652567fec40d626 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 12:57:44 -0500
Subject: [PATCH 1475/2348] test(map): repro #9628

---
 test/types.map.test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index a62004f7401..d5a7772c1e6 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -956,4 +956,24 @@ describe('Map', function() {
       assert.equal(board.elements.size, 0);
     });
   });
+
+  it('supports `null` in map of subdocuments (gh-9628)', function() {
+    const testSchema = new Schema({
+      messages: { type: Map, of: new Schema({ _id: false, text: String }) }
+    });
+
+    const Test = db.model('Test', testSchema);
+
+    return co(function*() {
+      let doc = yield Test.create({
+        messages: { prop1: { text: 'test' }, prop2: null }
+      });
+
+      doc = yield Test.findById(doc);
+
+      assert.deepEqual(doc.messages.get('prop1').toObject(), { text: 'test' });
+      assert.strictEqual(doc.messages.get('prop2'), null);
+      assert.ifError(doc.validateSync());
+    });
+  });
 });

From 8b152e3d3006b5945da4896f581fb42531b8ea9a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 13:31:11 -0500
Subject: [PATCH 1476/2348] fix(map): support `null` in maps of subdocs

Fix #9628
---
 lib/schema/map.js | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/schema/map.js b/lib/schema/map.js
index 468faea9c07..30e3eba8b30 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -31,11 +31,23 @@ class Map extends SchemaType {
 
       if (val instanceof global.Map) {
         for (const key of val.keys()) {
-          map.$init(key, map.$__schemaType.cast(val.get(key), doc, true));
+          let _val = val.get(key);
+          if (_val == null) {
+            _val = map.$__schemaType._castNullish(_val);
+          } else {
+            _val = map.$__schemaType.cast(_val, doc, true);
+          }
+          map.$init(key, _val);
         }
       } else {
         for (const key of Object.keys(val)) {
-          map.$init(key, map.$__schemaType.cast(val[key], doc, true));
+          let _val = val[key];
+          if (_val == null) {
+            _val = map.$__schemaType._castNullish(_val);
+          } else {
+            _val = map.$__schemaType.cast(_val, doc, true);
+          }
+          map.$init(key, _val);
         }
       }
 

From a85adb9ef076096cb9b5d4a08dfd0d268b54c2a3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 13:36:56 -0500
Subject: [PATCH 1477/2348] test: fix tests re: #9669

---
 test/typescript/main.test.js            |  9 ---------
 test/typescript/schemaGettersSetters.ts | 22 ----------------------
 2 files changed, 31 deletions(-)
 delete mode 100644 test/typescript/schemaGettersSetters.ts

diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index e094f95341c..742d4e160de 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -31,15 +31,6 @@ describe('typescript syntax', function() {
     assert.equal(errors.length, 0);
   });
 
-  it('reports error on invalid getter syntax', function() {
-    const errors = runTest('schemaGettersSetters.ts');
-    if (process.env.D && errors.length) {
-      console.log(errors);
-    }
-    assert.equal(errors.length, 1);
-    assert.ok(errors[0].messageText.messageText.includes('incorrect: number'), errors[0].messageText.messageText);
-  });
-
   it('handles maps', function() {
     const errors = runTest('maps.ts');
     if (process.env.D && errors.length) {
diff --git a/test/typescript/schemaGettersSetters.ts b/test/typescript/schemaGettersSetters.ts
deleted file mode 100644
index 8b6307633ba..00000000000
--- a/test/typescript/schemaGettersSetters.ts
+++ /dev/null
@@ -1,22 +0,0 @@
-import { Schema } from 'mongoose';
-
-const schema: Schema = new Schema({
-  name: {
-    type: 'String',
-    get: (v: string) => v.toUpperCase(),
-    set: (v: string) => v.toUpperCase(),
-    cast: 'Invalid name',
-    enum: ['hello']
-  },
-  buffer: {
-    type: Buffer,
-    subtype: 4
-  }
-});
-
-const schema2: Schema = new Schema({
-  name: {
-    type: 'String',
-    get: { incorrect: 42 }
-  }
-});
\ No newline at end of file

From 6d9fb4da26a9109aa0e4b959feb36be4d5e08fbb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 13:48:05 -0500
Subject: [PATCH 1478/2348] fix(index.d.ts): add missing `SchemaTypeOpts` and
 `ConnectionOptions` aliases for backwards compat

---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index fe8a3f154a2..ca8f16509b9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2497,4 +2497,7 @@ declare module "mongoose" {
   interface HookDoneFunction {
     (error?: Error): any;
   }
+
+  export type SchemaTypeOpts<T> = SchemaTypeOptions<T>;
+  export type ConnectionOptions = ConnectOptions;
 }

From 0e2058d55cf317076589bdbdb5044b663d1c23c4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 7 Dec 2020 13:52:20 -0500
Subject: [PATCH 1479/2348] chore: release 5.11.5

---
 History.md   | 19 +++++++++++++++++++
 package.json |  2 +-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index cc9fbf9b469..664f92a85c0 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,22 @@
+5.11.5 / 2020-12-07
+===================
+ * fix(map): support `null` in maps of subdocs #9628
+ * fix(index.d.ts): support object syntax for `validate` #9667
+ * fix(index.d.ts): Allow number for Schema expires #9670 [alecgibson](https://github.com/alecgibson)
+ * fix(index.d.ts): allow definining arbitrary properties on SchemaTypeOpts for plugins like mongoose-autopopulate #9669
+ * fix(index.d.ts): add mongoose.models #9661 #9660 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(index.d.ts): allow the next() argument to be optional #9665 #9664 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): add missing `VirtualType#applyGetters()` and `applySetters()`, `Schema#virtuals`, `Schema#childSchemas`, `Query#_mongooseOptions` #9658
+ * fix(index.d.ts): add `id` to LeanDocuments in case it is defined in the user's schema #9657
+ * fix(index.d.ts): add missing types for hook functions #9653
+ * fix(index.d.ts): improve support for strict null checks with `upsert` and `orFail()` #9654
+ * fix(index.d.ts): make return values for `insertMany()` more consistent #9662
+ * fix(index.d.ts): Change options in Connection#collection() to be optional #9663 [orgads](https://github.com/orgads)
+ * fix(index.d.ts): add the missing generic declaration for Schema #9655 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): add missing `SchemaTypeOpts` and `ConnectionOptions` aliases for backwards compat
+ * docs(populate): remove `sort()` from `limit` example to avoid potential confusion #9584
+ * docs(compatibility): add MongoDB server 4.4 version compatibility #9641
+
 5.11.4 / 2020-12-04
 ===================
  * fix(index.d.ts): add `Document#__v` so documents have a Version by default #9652 [sahasayan](https://github.com/sahasayan)
diff --git a/package.json b/package.json
index 4bb69887bde..40fab63612e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.4",
+  "version": "5.11.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 067e3a23bde478355707388c9f3d26ce3ccb87f2 Mon Sep 17 00:00:00 2001
From: Orgad Shaneh <orgad.shaneh@audiocodes.com>
Date: Tue, 8 Dec 2020 17:27:03 +0200
Subject: [PATCH 1480/2348] fix(index.d.ts): Fix return type of
 Model#aggregate()

Type 'Promise<unknown>' is not assignable to type 'Promise<Document>'.
---
 index.d.ts                | 4 ++--
 test/typescript/models.ts | 2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index ca8f16509b9..fe775a0ae57 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -578,8 +578,8 @@ declare module "mongoose" {
   interface Model<T extends Document> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
-    aggregate<R>(pipeline?: any[]): Aggregate<Array<R>>;
-    aggregate<R>(pipeline: any[], cb: Function): Promise<Array<R>>;
+    aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
+    aggregate<R = any>(pipeline: any[], cb: Function): Promise<Array<R>>;
 
     /** Base Mongoose instance the model uses. */
     base: typeof mongoose;
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 19a211e9d9b..4d8a893cb65 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -21,3 +21,5 @@ const ExpiresSchema = new Schema({
     expires: 3600,
   },
 });
+
+const aggregated: Promise<Document> = Test.aggregate([]).then(res => res[0]);

From 1ef8274b3e02fbb3f85d8d444f863046b9fed556 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 8 Dec 2020 10:54:41 -0500
Subject: [PATCH 1481/2348] fix(middleware): ensure sync errors in pre hooks
 always bubble up to the calling code

Fix #9659
---
 package.json          |  2 +-
 test/document.test.js | 17 +++++++++++++++++
 test/model.test.js    |  8 ++++----
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/package.json b/package.json
index 40fab63612e..6e7b401fbf7 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
   "dependencies": {
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
-    "kareem": "2.3.1",
+    "kareem": "2.3.2",
     "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.0",
diff --git a/test/document.test.js b/test/document.test.js
index 301cfab3f9f..dd4767d48d9 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9788,4 +9788,21 @@ describe('document', function() {
     assert.ok(documentFromDefault === user);
     assert.equal(documentFromDefault.name, 'Hafez');
   });
+
+  it('handles pre hook throwing a sync error (gh-9659)', function() {
+    const TestSchema = new Schema({ name: String });
+
+    TestSchema.pre('save', function() {
+      throw new Error('test err');
+    });
+    const TestModel = db.model('Test', TestSchema);
+
+    return co(function*() {
+      const testObject = new TestModel({ name: 't' });
+
+      const err = yield testObject.save().then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.message, 'test err');
+    });
+  });
 });
diff --git a/test/model.test.js b/test/model.test.js
index 8a54e946d65..9e43bc30396 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -1603,14 +1603,14 @@ describe('Model', function() {
       let docMiddleware = 0;
       let queryMiddleware = 0;
 
-      schema.pre('remove', { query: true }, function() {
-        assert.ok(this instanceof Model.Query);
+      schema.pre('remove', { query: true, document: false }, function() {
         ++queryMiddleware;
+        assert.ok(this instanceof Model.Query);
       });
 
-      schema.pre('remove', { document: true }, function() {
-        assert.ok(this instanceof Model);
+      schema.pre('remove', { query: false, document: true }, function() {
         ++docMiddleware;
+        assert.ok(this instanceof Model);
       });
 
       const Model = db.model('Test', schema);

From 8e20ee6b5abd9455177b05fb73673cc6fa1a5a58 Mon Sep 17 00:00:00 2001
From: isengartz <kontokostas.thanasis@gmail.com>
Date: Tue, 8 Dec 2020 19:18:22 +0200
Subject: [PATCH 1482/2348] optional next() parameter for post middleware

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index fe775a0ae57..11d503e6e33 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1082,12 +1082,12 @@ declare module "mongoose" {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;

From 61595f065cd018fc3cc13d39cf382d45b26e9a5a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 8 Dec 2020 12:41:16 -0500
Subject: [PATCH 1483/2348] fix(index.d.ts): allow passing ObjectId properties
 as strings to `create()` and `findOneAndReplace()`

Fix #9676
---
 index.d.ts                 | 5 ++++-
 test/typescript/create.ts  | 5 +++--
 test/typescript/queries.ts | 1 +
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index fe775a0ae57..e35c44140cc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2110,7 +2110,10 @@ declare module "mongoose" {
 
   export type UpdateQuery<T> = mongodb.UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
 
-  export type DocumentDefinition<T> = Omit<T, Exclude<keyof Document, '_id'>>;
+  type _AllowStringsForIds<T> = {
+    [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;
+  };
+  export type DocumentDefinition<T> = _AllowStringsForIds<Omit<T, Exclude<keyof Document, '_id'>>>;
 
   type FunctionPropertyNames<T> = {
     // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
index 65e57fc5533..98cfa653003 100644
--- a/test/typescript/create.ts
+++ b/test/typescript/create.ts
@@ -1,14 +1,15 @@
-import { Schema, model, Document } from 'mongoose';
+import { Schema, model, Document, Types } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
 interface ITest extends Document {
+  _id?: Types.ObjectId;
   name?: string;
 }
 
 const Test = model<ITest>('Test', schema);
 
-Test.create({ name: 'test' }).then((doc: ITest) => console.log(doc.name));
+Test.create({ _id: '0'.repeat(24), name: 'test' }).then((doc: ITest) => console.log(doc.name));
 
 Test.create([{ name: 'test' }], { validateBeforeSave: false }).then((docs: ITest[]) => console.log(docs[0].name));
 
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index ca4d17a9f82..cf4fe4b6c95 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -13,6 +13,7 @@ const Test = model<ITest>('Test', schema);
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
 
 Test.find({ parent: new Types.ObjectId('0'.repeat(24)) });
+Test.find({ parent: '0'.repeat(24) });
 
 Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => console.log(res));
 

From 48907ea333aa5ad6e43dd701863d935cde7ddbe7 Mon Sep 17 00:00:00 2001
From: Sayan Saha <sayan@page2.page>
Date: Wed, 9 Dec 2020 04:40:33 +0530
Subject: [PATCH 1484/2348] fix(index.d.ts): allow 2 generic types in
 mongoose.model function

---
 index.d.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index c78ba6045cc..9a75406a7e2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,6 +99,12 @@ declare module "mongoose" {
   export function isValidObjectId(v: any): boolean;
 
   export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
+  export function model<T extends Document, U extends Model<T>>(
+    name: string,
+    schema?: Schema,
+    collection?: string,
+    skipInit?: boolean
+  ): U;
 
   /** Returns an array of model names created on this instance of Mongoose. */
   export function modelNames(): Array<string>;

From a5c98c22f04c33bf114f2ba30553b006c066f864 Mon Sep 17 00:00:00 2001
From: cjroebuck <tophtfc@gmail.com>
Date: Tue, 8 Dec 2020 23:43:30 +0000
Subject: [PATCH 1485/2348] Allow array of validators in SchemaTypeOptions

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index c78ba6045cc..6552d31ec7a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1303,7 +1303,7 @@ declare module "mongoose" {
     alias?: string;
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    validate?: RegExp | [RegExp, string] | Function | [Function , string] | ValidateOpts<T>;
+    validate?: RegExp | [RegExp, string] | Function | [Function , string] | ValidateOpts<T> | ValidateOpts<T>[];
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
     cast?: string;

From 6ee16de560435d6d5876833f7fe0eb56fa452f17 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Wed, 9 Dec 2020 13:20:44 +1100
Subject: [PATCH 1486/2348] chore: add Github Actions

---
 .github/workflows/test.yml | 53 ++++++++++++++++++++++++++++++++++++++
 test/common.js             |  1 +
 2 files changed, 54 insertions(+)
 create mode 100644 .github/workflows/test.yml

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 00000000000..86a0622b11d
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,53 @@
+on: push
+jobs:
+  test:
+    runs-on: ubuntu-16.04
+    strategy:
+      fail-fast: false
+      matrix:
+        node: [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]
+    name: Node ${{ matrix.node }}
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Setup node
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node }}
+
+      - name: Upgrade Node 5 npm
+        run: npm install -g npm@3
+        if: ${{ matrix.node == 5 }}
+
+      - run: npm install
+
+      - name: Setup
+        run: |
+          wget -q http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
+          tar xf mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
+          mkdir -p ./data/db/27017 ./data/db/27000
+          printf "\n--timeout 8000" >> ./test/mocha.opts
+          ./mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+          sleep 2
+          mongod --version
+          mkdir ./test/typescript/node_modules
+          ln -s `pwd` ./test/typescript/node_modules/mongoose
+          echo `pwd`/mongodb-linux-x86_64-ubuntu1604-4.0.2/bin >> $GITHUB_PATH
+
+      - run: npm test
+
+  lint:
+    runs-on: ubuntu-latest
+    name: Linter
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Setup node
+        uses: actions/setup-node@v1
+        with:
+          node-version: 15
+
+      - run: npm install eslint
+
+      - name: Linter
+        run: npm run lint
diff --git a/test/common.js b/test/common.js
index 170375aa6b8..80ffac4f9b9 100644
--- a/test/common.js
+++ b/test/common.js
@@ -215,6 +215,7 @@ after(function(done) {
 });
 
 module.exports.server = server = new Server('mongod', {
+  bind_ip: '127.0.0.1',
   port: 27000,
   dbpath: './data/db/27000'
 });

From 7b98ec4771f7d70450673ae57aafc76a9bdd5adc Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Wed, 9 Dec 2020 22:06:46 +1100
Subject: [PATCH 1487/2348] give name to workflow

---
 .github/workflows/test.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 86a0622b11d..f493760d3ed 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -1,3 +1,4 @@
+name: Test
 on: push
 jobs:
   test:

From f78380037c19fb56e36eee79224241dfb7deb4c6 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Wed, 9 Dec 2020 23:12:00 +1100
Subject: [PATCH 1488/2348] upgrade to 18.04

---
 .github/workflows/test.yml   | 14 +++++++-------
 test/typescript/main.test.js |  2 +-
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index f493760d3ed..208e3ca1caa 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -2,7 +2,7 @@ name: Test
 on: push
 jobs:
   test:
-    runs-on: ubuntu-16.04
+    runs-on: ubuntu-18.04
     strategy:
       fail-fast: false
       matrix:
@@ -24,16 +24,16 @@ jobs:
 
       - name: Setup
         run: |
-          wget -q http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
-          tar xf mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
+          wget -q http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1804-4.0.2.tgz
+          tar xf mongodb-linux-x86_64-ubuntu1804-4.0.2.tgz
           mkdir -p ./data/db/27017 ./data/db/27000
           printf "\n--timeout 8000" >> ./test/mocha.opts
-          ./mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+          ./mongodb-linux-x86_64-ubuntu1804-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
           sleep 2
           mongod --version
           mkdir ./test/typescript/node_modules
           ln -s `pwd` ./test/typescript/node_modules/mongoose
-          echo `pwd`/mongodb-linux-x86_64-ubuntu1604-4.0.2/bin >> $GITHUB_PATH
+          echo `pwd`/mongodb-linux-x86_64-ubuntu1804-4.0.2/bin >> $GITHUB_PATH
 
       - run: npm test
 
@@ -46,9 +46,9 @@ jobs:
       - name: Setup node
         uses: actions/setup-node@v1
         with:
-          node-version: 15
+          node-version: 14
 
-      - run: npm install eslint
+      - run: npm install
 
       - name: Linter
         run: npm run lint
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 742d4e160de..bf43c5647e1 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -5,7 +5,7 @@ const typescript = require('typescript');
 const tsconfig = require('./tsconfig.json');
 
 describe('typescript syntax', function() {
-  this.timeout(10000);
+  this.timeout(60000);
 
   it('base', function() {
     const errors = runTest('base.ts');

From 3ec01fae81fb06b2f9faeb18f4b898779d59c4ab Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Dec 2020 12:28:03 -0500
Subject: [PATCH 1489/2348] fix(index.d.ts): allow calling `mongoose.model()`
 and `Connection#model()` with model as generic param

Fix #9678
---
 index.d.ts                |  6 ++++++
 test/typescript/models.ts | 14 ++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index e98fa67f1c0..1e29f4d32dc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -242,6 +242,12 @@ declare module "mongoose" {
 
     /** Defines or retrieves a model. */
     model<T extends Document>(name: string, schema?: Schema, collection?: string): Model<T>;
+    model<T extends Document, U extends Model<T>>(
+      name: string,
+      schema?: Schema,
+      collection?: string,
+      skipInit?: boolean
+    ): U;
 
     /** Returns an array of model names created on this connection. */
     modelNames(): Array<string>;
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 4d8a893cb65..6184796c642 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -23,3 +23,17 @@ const ExpiresSchema = new Schema({
 });
 
 const aggregated: Promise<Document> = Test.aggregate([]).then(res => res[0]);
+
+interface IProject extends Document {
+  name: String;
+}
+
+interface ProjectModel extends Model<IProject> {
+  myStatic(): number;
+}
+
+const projectSchema: Schema = new Schema({ name: String });
+projectSchema.statics.myStatic = () => 42;
+
+const Project = connection.model<IProject, ProjectModel>('Project', projectSchema);
+Project.myStatic();
\ No newline at end of file

From dd348b1e5ad7b6b0b07c8e3f3aaaa67f87bd2c45 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 9 Dec 2020 12:42:06 -0500
Subject: [PATCH 1490/2348] chore: release 5.11.6

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 664f92a85c0..3b5cd3e3fdd 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.11.6 / 2020-12-09
+===================
+ * fix(middleware): ensure sync errors in pre hooks always bubble up to the calling code #9659
+ * fix(index.d.ts): allow passing ObjectId properties as strings to `create()` and `findOneAndReplace()` #9676
+ * fix(index.d.ts): allow calling `mongoose.model()` and `Connection#model()` with model as generic param #9685 #9678 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): Fix return type of Model#aggregate() #9680 [orgads](https://github.com/orgads)
+ * fix(index.d.ts): optional next() parameter for post middleware #9683 [isengartz](https://github.com/isengartz)
+ * fix(index.d.ts): allow array of validators in SchemaTypeOptions #9686 [cjroebuck](https://github.com/cjroebuck)
+
 5.11.5 / 2020-12-07
 ===================
  * fix(map): support `null` in maps of subdocs #9628
diff --git a/package.json b/package.json
index 6e7b401fbf7..c40368d8af9 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.5",
+  "version": "5.11.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 15d6660a319b8b0edf8560f14ec1dbf08363b043 Mon Sep 17 00:00:00 2001
From: Sayan Saha <sayan@page2.page>
Date: Thu, 10 Dec 2020 14:29:50 +0530
Subject: [PATCH 1491/2348] fix(index.d.ts): add missing Aggregate#skip() &
 Aggregate#limit()

---
 index.d.ts | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 1e29f4d32dc..a87dae0a276 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2236,6 +2236,12 @@ declare module "mongoose" {
     /** Sets the hint option for the aggregation query (ignored for < 3.6.0) */
     hint(value: object | string): this;
 
+    /**
+     * Appends a new $limit operator to this aggregate pipeline.
+     * @param num maximum number of records to pass to the next stage
+     */
+    limit(num: number): this;
+                                          
     /** Appends new custom $lookup operator to this aggregate pipeline. */
     lookup(options: any): this;
 
@@ -2265,6 +2271,12 @@ declare module "mongoose" {
 
     /** Sets the session for this aggregation. Useful for [transactions](/docs/transactions.html). */
     session(session: mongodb.ClientSession | null): this;
+    
+    /**
+     * Appends a new $skip operator to this aggregate pipeline.
+     * @param num number of records to skip before next stage
+     */
+    skip(num: number): this;
 
     /** Appends a new $sort operator to this aggregate pipeline. */
     sort(arg: any): this;

From 28dc9cc5ca01b88ae0a321116bf91d62ced0c96b Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Thu, 10 Dec 2020 22:15:49 +1100
Subject: [PATCH 1492/2348] increase server.stop() timeout

---
 test/connection.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index 45e7ff54e04..74fa858d4f6 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -223,7 +223,7 @@ describe('connections:', function() {
           }).
           then(function() {
             return new Promise(function(resolve) {
-              setTimeout(function() { resolve(); }, 1000);
+              setTimeout(function() { resolve(); }, 3000);
             });
           }).
           then(function() {

From cfae5c18da17fac74cca1a35e4674841cd207322 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Thu, 10 Dec 2020 22:18:58 +1100
Subject: [PATCH 1493/2348] fix(test): wait for promises to complete

prevents Uncaught MongoError: Cannot use a session that has ended in after all hook
---
 test/es-next/promises.test.es6.js | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/test/es-next/promises.test.es6.js b/test/es-next/promises.test.es6.js
index f31d05aadd7..4e4c8ad08b5 100644
--- a/test/es-next/promises.test.es6.js
+++ b/test/es-next/promises.test.es6.js
@@ -170,14 +170,19 @@ describe('promises docs', function () {
 
     // Use bluebird
     mongoose.Promise = require('bluebird');
-    assert.equal(query.exec().constructor, require('bluebird'));
+    const bluebirdPromise = query.exec();
+    assert.equal(bluebirdPromise.constructor, require('bluebird'));
 
     // Use q. Note that you **must** use `require('q').Promise`.
     mongoose.Promise = require('q').Promise;
-    assert.ok(query.exec() instanceof require('q').makePromise);
+    const qPromise = query.exec();
+    assert.ok(qPromise instanceof require('q').makePromise);
 
     // acquit:ignore:start
-    done();
+    // Wait for promises
+    bluebirdPromise.then(qPromise).then(function () {
+      done();
+    });
     // acquit:ignore:end
   });
 });

From b2da8406677e9b8366380c0b8ce5e478dfc17904 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 09:25:54 -0500
Subject: [PATCH 1494/2348] test(model): repro #9677

---
 test/model.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 9e43bc30396..5e0fc54d1f5 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4726,6 +4726,25 @@ describe('Model', function() {
       });
     });
 
+    it('insertMany() sets `isNew` for inserted documents with `ordered = false` (gh-9677)', function() {
+      const schema = new Schema({
+        title: { type: String, required: true, unique: true }
+      });
+      const Movie = db.model('Movie', schema);
+
+      const arr = [{ title: 'The Phantom Menace' }, { title: 'The Phantom Menace' }];
+      const opts = { ordered: false };
+      return co(function*() {
+        yield Movie.init();
+        const err = yield Movie.insertMany(arr, opts).then(() => err, err => err);
+        assert.ok(err);
+        assert.ok(err.insertedDocs);
+
+        assert.equal(err.insertedDocs.length, 1);
+        assert.strictEqual(err.insertedDocs[0].isNew, false);
+      });
+    });
+
     it('insertMany() validation error with ordered true and rawResult true when all documents are invalid', function(done) {
       const schema = new Schema({
         name: { type: String, required: true }

From 1be4d873a9e2cfd8afe7f8d213624bdc5d446029 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 09:26:11 -0500
Subject: [PATCH 1495/2348] fix(model): set `isNew` to false for documents that
 were successfully inserted by `insertMany` with `ordered = false` when an
 error occurred

Fix #9677
---
 lib/model.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 78f50348e9e..4b2e514ccfd 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3332,9 +3332,13 @@ Model.$__insertMany = function(arr, options, callback) {
 
         // `insertedDocs` is a Mongoose-specific property
         const erroredIndexes = new Set(get(error, 'writeErrors', []).map(err => err.index));
-        error.insertedDocs = docAttributes.filter((doc, i) => {
-          return !erroredIndexes.has(i);
-        });
+        error.insertedDocs = docAttributes.
+          filter((doc, i) => !erroredIndexes.has(i)).
+          map(function setIsNewForInsertedDoc(doc) {
+            doc.$__reset();
+            _setIsNew(doc, false);
+            return doc;
+          });
 
         callback(error, null);
         return;

From f879c4d346bfdfcb1f24b1fd214d961265d1a1e5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 10:40:31 -0500
Subject: [PATCH 1496/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index b5c6de66582..a69048bba7c 100644
--- a/index.pug
+++ b/index.pug
@@ -379,6 +379,9 @@ html(lang='en')
               <a rel="sponsored" href="https://goread.io/buy-instagram-likes">
                 <img class="sponsor" src="https://goread.io/assets/images/Goreadlogo.png" style="height: 100px" alt="Buy Instagram Likes">
               </a>
+              <a rel="sponsored" href="https://followerspromotion.com/buy-instagram-likes/">
+                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/followerspromo.png" style="height: 100px" alt="Buy Instagram Likes">
+              </a>
             </div>
           </div>
 

From 43f88db18228418daf783fcfdc23c95fba49615d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 14:59:16 -0500
Subject: [PATCH 1497/2348] fix(document): ensure calling `get()` with empty
 string returns undefined for mongoose-plugin-autoinc

Fix #9681
---
 package.json          | 2 +-
 test/document.test.js | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index c40368d8af9..6a63dc64ef7 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "kareem": "2.3.2",
     "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
-    "mpath": "0.8.0",
+    "mpath": "0.8.1",
     "mquery": "3.2.2",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
diff --git a/test/document.test.js b/test/document.test.js
index dd4767d48d9..7c84cf539b1 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9805,4 +9805,13 @@ describe('document', function() {
       assert.equal(err.message, 'test err');
     });
   });
+
+  it('returns undefined rather than entire object when calling `get()` with empty string (gh-9681)', function() {
+    const TestSchema = new Schema({ name: String });
+    const TestModel = db.model('Test', TestSchema);
+
+    const testObject = new TestModel({ name: 't' });
+
+    assert.strictEqual(testObject.get(''), void 0);
+  });
 });

From a9b317a31cdb7a160740f2dfa50da6a891b78401 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 18:00:36 -0500
Subject: [PATCH 1498/2348] chore: upgrade mquery -> 3.2.3

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 6a63dc64ef7..8469a5afd02 100644
--- a/package.json
+++ b/package.json
@@ -25,7 +25,7 @@
     "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.1",
-    "mquery": "3.2.2",
+    "mquery": "3.2.3",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.2.1",

From d318339967edca3b8405b2961705edc2186bd5d0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 18:08:51 -0500
Subject: [PATCH 1499/2348] fix(index.d.ts): make `Document#id` optional so
 types that use `id` can use `Model<IMyType & Document>`

Fix #9684
---
 index.d.ts                |  2 +-
 test/typescript/models.ts | 38 +++++++++++++++++++++++++++-----------
 2 files changed, 28 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index a87dae0a276..59e53478e7b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -475,7 +475,7 @@ declare module "mongoose" {
     getChanges(): UpdateQuery<this>;
 
     /** The string version of this documents _id. */
-    id: string;
+    id?: string;
 
     /** Signal that we desire an increment of this documents version. */
     increment(): this;
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 6184796c642..4b4bb75a63f 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -1,19 +1,37 @@
 import { Schema, Document, Model, connection } from 'mongoose';
 
-interface ITest extends Document {
-  foo: string;
+function conventionalSyntax(): void {
+  interface ITest extends Document {
+    foo: string;
+  }
+  
+  const TestSchema = new Schema({
+    foo: { type: String, required: true },
+  });
+  
+  const Test = connection.model<ITest>('Test', TestSchema);
+  
+  const bar = (SomeModel: Model<ITest>) => console.log(SomeModel);
+  
+  bar(Test);
 }
 
-const TestSchema = new Schema({
-  foo: { type: String, required: true },
-});
+function tAndDocSyntax(): void {
+  interface ITest {
+    id: number;
+    foo: string;
+  }
+  
+  const TestSchema = new Schema({
+    foo: { type: String, required: true },
+  });
 
-const Test = connection.model<ITest>('Test', TestSchema);
+  const Test = connection.model<ITest & Document>('Test', TestSchema);
 
-const bar = (SomeModel: Model<ITest>) => // <<<< error here
-  console.log(SomeModel);
+  const aggregated: Promise<Document> = Test.aggregate([]).then(res => res[0]);
 
-bar(Test);
+  const bar = (SomeModel: Model<ITest & Document>) => console.log(SomeModel);
+}
 
 const ExpiresSchema = new Schema({
   ttl: {
@@ -22,8 +40,6 @@ const ExpiresSchema = new Schema({
   },
 });
 
-const aggregated: Promise<Document> = Test.aggregate([]).then(res => res[0]);
-
 interface IProject extends Document {
   name: String;
 }

From d7fc59c355e25d16830591b191b7473ac8f88626 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 18:22:07 -0500
Subject: [PATCH 1500/2348] chore: release 5.11.7

---
 History.md   | 7 +++++++
 package.json | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 3b5cd3e3fdd..ef64e41f121 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,10 @@
+5.11.7 / 2020-12-10
+===================
+ * fix(document): ensure calling `get()` with empty string returns undefined for mongoose-plugin-autoinc #9681
+ * fix(model): set `isNew` to false for documents that were successfully inserted by `insertMany` with `ordered = false` when an error occurred #9677
+ * fix(index.d.ts): add missing Aggregate#skip() & Aggregate#limit() #9692 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): make `Document#id` optional so types that use `id` can use `Model<IMyType & Document>` #9684
+
 5.11.6 / 2020-12-09
 ===================
  * fix(middleware): ensure sync errors in pre hooks always bubble up to the calling code #9659
diff --git a/package.json b/package.json
index 8469a5afd02..a1011f5c6d4 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.6",
+  "version": "5.11.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 8097d05e09ef2c90f25c2d5dc4c63f78b642a556 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 18:37:15 -0500
Subject: [PATCH 1501/2348] chore(.npmignore): try alternative approach for
 #9404 because npm isnt ignoring the changelog

---
 .npmignore | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.npmignore b/.npmignore
index ee24d516dbc..882a4bf0bf7 100644
--- a/.npmignore
+++ b/.npmignore
@@ -24,7 +24,7 @@ examples/
 .vscode
 .eslintignore
 CONTRIBUTING.md
-History.md
+History.*
 format_deps.js
 release-items.md
 static.js

From 7f899cecc908f7c61ffcb1a7550b99476822a1de Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 10 Dec 2020 19:11:00 -0500
Subject: [PATCH 1502/2348] docs: add a couple links to clarifying articles

---
 docs/guide.pug | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 92f54d43121..819080193fe 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -316,7 +316,8 @@ block content
     console.log(axl.name.first + ' ' + axl.name.last); // Axl Rose
     ```
 
-    But concatenating the first and last name every time can get cumbersome.
+    But [concatenating](https://masteringjs.io/tutorials/fundamentals/string-concat) the first and
+    last name every time can get cumbersome.
     And what if you want to do some extra processing on the name, like
     [removing diacritics](https://www.npmjs.com/package/diacritics)? A
     [virtual property getter](./api.html#virtualtype_VirtualType-get) lets you
@@ -364,6 +365,8 @@ block content
     Only non-virtual properties work as part of queries and for field selection.
     Since virtuals are not stored in MongoDB, you can't query with them.
 
+    You can [learn more about virtuals here](https://masteringjs.io/tutorials/mongoose/virtuals).
+
     <h3 id="aliases"><a href="#aliases">Aliases</a></h3>
 
     Aliases are a particular type of virtual where the getter and setter
@@ -815,7 +818,7 @@ block content
     <h3 id="toJSON"><a href="#toJSON">option: toJSON</a></h3>
 
     Exactly the same as the [toObject](#toObject) option but only applies when
-    the document's `toJSON` method is called.
+    the document's [`toJSON` method](https://thecodebarbarian.com/what-is-the-tojson-function-in-javascript.html) is called.
 
     ```javascript
     const schema = new Schema({ name: String });

From 2c4309ead246be00e781c84ad938e5d88a1b2014 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Fri, 11 Dec 2020 20:06:05 +1100
Subject: [PATCH 1503/2348] fix(index.d.ts): add missing single document
 populate

---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 59e53478e7b..c9d0aabede6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -724,6 +724,8 @@ declare module "mongoose" {
     /** Populates document references. */
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
       callback?: (err: any, res: T[]) => void): Promise<Array<T>>;
+    populate(doc: any, options: PopulateOptions | Array<PopulateOptions> | string,
+      callback?: (err: any, res: T) => void): Promise<T>;
 
     /**
      * Makes the indexes in MongoDB match the indexes defined in this model's

From d8faf052801dd668ae65f096d82e006dfeffdce7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Dec 2020 11:08:59 -0500
Subject: [PATCH 1504/2348] fix(index.d.ts): don't require document methods
 when calling `Model.create()`

Fix #9695
---
 index.d.ts                   |  2 +-
 test/typescript/main.test.js |  8 ++++++++
 test/typescript/methods.ts   | 22 ++++++++++++++++++++++
 3 files changed, 31 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/methods.ts

diff --git a/index.d.ts b/index.d.ts
index 59e53478e7b..526866729c3 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2125,7 +2125,7 @@ declare module "mongoose" {
   type _AllowStringsForIds<T> = {
     [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;
   };
-  export type DocumentDefinition<T> = _AllowStringsForIds<Omit<T, Exclude<keyof Document, '_id'>>>;
+  export type DocumentDefinition<T> = _AllowStringsForIds<Omit<Omit<T, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>>;
 
   type FunctionPropertyNames<T> = {
     // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 742d4e160de..18ee778bac8 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -164,6 +164,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('methods', function() {
+    const errors = runTest('methods.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file) {
diff --git a/test/typescript/methods.ts b/test/typescript/methods.ts
new file mode 100644
index 00000000000..7fe90a4755b
--- /dev/null
+++ b/test/typescript/methods.ts
@@ -0,0 +1,22 @@
+import { Schema, Document, connection } from 'mongoose';
+
+interface ITest extends Document {
+  foo: string;
+  getAnswer(): number;
+}
+
+const TestSchema = new Schema({
+  foo: { type: String, required: true },
+});
+
+TestSchema.methods.getAnswer = function(): number {
+  return 42;
+}
+
+const Test = connection.model<ITest>('Test', TestSchema);
+
+Test.create({ foo: 'test' });
+
+const doc: ITest = new Test({ foo: 'test' });
+
+Math.floor(doc.getAnswer());
\ No newline at end of file

From ae6e8d01338f31c07d3c3a26e52afbec0f3e3d7f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Dec 2020 11:41:02 -0500
Subject: [PATCH 1505/2348] fix(index.d.ts): loosen type bindings for
 `Query#toConstructor()` to prevent them from conflicting with discriminator
 inheritance

Fix #9679
---
 index.d.ts                       |  2 +-
 test/typescript/discriminator.ts | 57 ++++++++++++++++++++++++++++++--
 test/typescript/main.test.js     |  6 ++--
 3 files changed, 59 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 526866729c3..be29dc22e68 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2068,7 +2068,7 @@ declare module "mongoose" {
     then: Promise<ResultType>["then"];
 
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
-    toConstructor(): new (filter?: FilterQuery<DocType>, options?: QueryOptions) => Query<ResultType, DocType>;
+    toConstructor(): new (...args: any[]) => Query<ResultType, DocType>;
 
     /** Declare and/or execute this query as an update() operation. */
     update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
diff --git a/test/typescript/discriminator.ts b/test/typescript/discriminator.ts
index b2829ed3e25..30e43378107 100644
--- a/test/typescript/discriminator.ts
+++ b/test/typescript/discriminator.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document } from 'mongoose';
+import mongoose, { Document, Model, Schema, SchemaDefinition, SchemaOptions, Types, model } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
@@ -16,4 +16,57 @@ const Disc = Base.discriminator<IDiscriminatorTest>('Test2', new Schema({ email:
 const doc: IDiscriminatorTest = new Disc({ name: 'foo', email: 'hi' });
 
 doc.name = 'bar';
-doc.email = 'hello';
\ No newline at end of file
+doc.email = 'hello';
+
+function test(): void {
+  enum CardType {
+    Artifact = 'artifact',
+    Creature = 'creature',
+    Enchantment = 'enchantment',
+    Land = 'land',
+  }
+  
+  interface CardDb extends Document {
+    _id: Types.ObjectId;
+    type: CardType;
+  }
+  
+  interface LandDb extends CardDb {
+    type: CardType.Land;
+  }
+  
+  const cardDbBaseSchemaDefinition: SchemaDefinition = {
+    type: { type: String, required: true },
+  };
+  
+  const cardDbSchemaOptions: SchemaOptions = { discriminatorKey: 'type' };
+  
+  const cardDbSchema: Schema = new Schema(
+    cardDbBaseSchemaDefinition,
+    cardDbSchemaOptions,
+  );
+  
+  const cardDbModel: Model<CardDb> = mongoose.model<CardDb>(
+    'Card',
+    cardDbSchema,
+    'card',
+  );
+  
+  const landDbAdditionalPropertiesSchemaDefinition: SchemaDefinition = {};
+  
+  const landDbSchema: Schema = new Schema(
+    landDbAdditionalPropertiesSchemaDefinition,
+  );
+  
+  const landDbModel: Model<LandDb> = cardDbModel.discriminator<LandDb>(
+    'Land',
+    landDbSchema,
+    CardType.Land,
+  );
+  
+  const sampleLandDb: LandDb = new landDbModel({
+    type: CardType.Land,
+  });
+  
+  const sampleCardDb: CardDb = sampleLandDb;
+}
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 18ee778bac8..7fce268bb5e 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -73,7 +73,7 @@ describe('typescript syntax', function() {
   });
 
   it('discriminators', function() {
-    const errors = runTest('discriminator.ts');
+    const errors = runTest('discriminator.ts', { strict: true });
     if (process.env.D && errors.length) {
       console.log(errors);
     }
@@ -174,8 +174,8 @@ describe('typescript syntax', function() {
   });
 });
 
-function runTest(file) {
-  const program = typescript.createProgram([`${__dirname}/${file}`], tsconfig);
+function runTest(file, configOverride) {
+  const program = typescript.createProgram([`${__dirname}/${file}`], Object.assign({}, tsconfig, configOverride));
 
   const emitResult = program.emit();
 

From 26c860a73004c1c0ac54eef057cf66c0621853ea Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 11 Dec 2020 13:55:53 -0500
Subject: [PATCH 1506/2348] chore: update opencollective sponsors

---
 index.pug | 42 ------------------------------------------
 1 file changed, 42 deletions(-)

diff --git a/index.pug b/index.pug
index a69048bba7c..2e7e954feb7 100644
--- a/index.pug
+++ b/index.pug
@@ -202,12 +202,6 @@ html(lang='en')
               <a rel="sponsored" href="https://uiuxagencies.top/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F62223ab0-f4f7-11e8-919f-53f2ea21a967.png&height=100" style="height:100px">
               </a>
-              <a rel="sponsored" href="https://www.vpnranks.com/">
-                <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fvpnranks.com&height=100" style="height:100px">
-              </a>
-              <a rel="sponsored" href="https://www.bestvpn.co/">
-                <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fwww.bestvpn.co&height=100" style="height:100px">
-              </a>
               <a rel="sponsored" href="https://blokt.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fblokt.com&height=100" style="height:100px">
               </a>
@@ -301,42 +295,15 @@ html(lang='en')
               <a rel="sponsored" href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
                 <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://netticasinohex.com/kasinot/">
-                <img class="sponsor" src="https://images.opencollective.com/netticasinohex-com/71d7417/logo/256.png" style="height: 100px">
-              </a>
-              <a rel="sponsored" href="https://casinohex.at/online-casinos/">
-                <img class="sponsor" src="https://images.opencollective.com/casinohex-at/8e06f0e/logo/256.png" style="height: 100px">
-              </a>
-              <a rel="sponsored" href="https://casinohex.se/online-casinon/">
-                <img class="sponsor" src="https://images.opencollective.com/casinohex-se/795919b/logo/256.png" style="height: 100px">
-              </a>
-              <a rel="sponsored" href="https://casinohex.co.za/online-casinos/">
-                <img class="sponsor" src="https://images.opencollective.com/casinohex-co-za/470843d/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.casinofever.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinofever-ca1/4ad150e/logo/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://www.parhaatnettikasinot.com/">
                 <img class="sponsor" src="https://images.opencollective.com/parhaatnettikasinot-com/fc53017/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://swisscasinohex.com/online-casinos/">
-                <img class="sponsor" src="https://images.opencollective.com/swisscasinohex-com/107940c/logo/256.png" style="height: 100px">
-              </a>
-              <a rel="sponsored" href="https://onlinecasinohex.nl/online-casinos/nederland/">
-                <img class="sponsor" src="https://images.opencollective.com/onlinecasinohex-nl/ed24082/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://kasynohex.com/kasyna-online/">
                 <img class="sponsor" src="https://images.opencollective.com/kasynohex-com/b25daf6/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://casinohex.ro/online-cazino/">
-                <img class="sponsor" src="https://images.opencollective.com/casinohex-ro/493996e/logo/256.png" style="height: 100px">
-              </a>
-              <a rel="sponsored" href="https://norskcasinohex.com/casino-pa-nett/">
-                <img class="sponsor" src="https://images.opencollective.com/norskcasinohex-com/f0d4c76/logo/256.png" style="height: 100px">
-              </a>
-              <a rel="sponsored" href="https://aussiecasinohex.com/online-casinos/">
-                <img class="sponsor" src="https://images.opencollective.com/aussiecasinohex/923df37/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.japanesecasino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/japanesecasino/b0ffe3c/logo/256.png" style="height: 100px">
               </a>
@@ -346,15 +313,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.polskiekasyno.com/">
                 <img class="sponsor" src="https://images.opencollective.com/polskiekasyno-com/a8975c6/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://casinohex.in/online-casinos/">
-                <img class="sponsor" src="https://images.opencollective.com/casinohex-in/0d7625b/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.baocasino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/baocasino/b5a71c4/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://onlinecasinoguide.co.nz/">
-                <img class="sponsor" src="https://images.opencollective.com/onlinecasinoguide-co-nz/b16a388/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://casino-academia.jp/">
                 <img class="sponsor" src="https://images.opencollective.com/casinoacademia/90fc970/logo/256.png" style="height: 100px">
               </a>
@@ -364,9 +325,6 @@ html(lang='en')
               <a rel="sponsored" href="https://casinopro.ca/">
                 <img class="sponsor" src="https://images.opencollective.com/casinopro/4729b46/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://masonslots.com/">
-                <img class="sponsor" src="https://images.opencollective.com/masonslots/29251dd/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://twojtyp.pl/">
                 <img class="sponsor" src="https://images.opencollective.com/twojtyp/cd0b486/logo/256.png" style="height: 100px">
               </a>

From 1d8cdf0120ce382b7f4aa64e610631338e12e579 Mon Sep 17 00:00:00 2001
From: orblazer <orblazer.minecraft@gmail.com>
Date: Sat, 12 Dec 2020 01:59:57 +0100
Subject: [PATCH 1507/2348] fix(index.d.ts): allow specify type of _id

---
 index.d.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 0cf32f78e62..76e90fafb3d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -363,11 +363,11 @@ declare module "mongoose" {
     getIndexes(): any;
   }
 
-  class Document {
+  class Document<T = any> {
     constructor(doc?: any);
 
     /** This documents _id. */
-    _id?: any;
+    _id?: T;
 
     /** This documents __v. */
     __v?: number;
@@ -456,7 +456,7 @@ declare module "mongoose" {
      * document has an `_id`, in which case this function falls back to using
      * `deepEqual()`.
      */
-    equals(doc: Document): boolean;
+    equals(doc: Document<T>): boolean;
 
     /** Hash containing current validation errors. */
     errors?: Error.ValidationError;

From 85acf45ec3c3655a97b6a2f1b44b12ed82dda65f Mon Sep 17 00:00:00 2001
From: orblazer <orblazer.minecraft@gmail.com>
Date: Sat, 12 Dec 2020 02:19:21 +0100
Subject: [PATCH 1508/2348] fix(index.d.ts): make options optional for
 `toObject`

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 0cf32f78e62..19928e74f15 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1653,7 +1653,7 @@ declare module "mongoose" {
       shift(): T;
 
       /** Returns a native js Array. */
-      toObject(options: ToObjectOptions): any;
+      toObject(options?: ToObjectOptions): any;
 
       /** Wraps [`Array#unshift`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/unshift) with proper change tracking. */
       unshift(...args: any[]): number;
@@ -1695,7 +1695,7 @@ declare module "mongoose" {
 
     class Map<V> extends global.Map<string, V> {
       /** Converts a Mongoose map into a vanilla JavaScript map. */
-      toObject(options: ToObjectOptions & { flattenMaps?: boolean }): any;
+      toObject(options?: ToObjectOptions & { flattenMaps?: boolean }): any;
     }
 
     var ObjectId: ObjectIdConstructor;

From 3dbbf7d7823863dc92055abb75c500fb76470f18 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Dec 2020 21:13:43 -0500
Subject: [PATCH 1509/2348] refactor(index.d.ts): add MongooseQueryOptions type
 for `mongooseOptions()` and `_mongooseOptions`

---
 index.d.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 961d2eba0a6..e3af0c4c121 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -896,6 +896,8 @@ declare module "mongoose" {
     writeConcern?: any;
   }
 
+  type MongooseQueryOptions = Pick<QueryOptions, "populate" | "lean" | "omitUndefined" | "strict" | "useFindAndModify">;
+
   interface SaveOptions {
     checkKeys?: boolean;
     j?: boolean;
@@ -1725,7 +1727,7 @@ declare module "mongoose" {
   }
 
   interface Query<ResultType, DocType extends Document> {
-    _mongooseOptions: QueryOptions;
+    _mongooseOptions: MongooseQueryOptions;
 
     exec(): Promise<ResultType>;
     exec(callback?: (err: CallbackError, res: ResultType) => void): void;
@@ -1944,7 +1946,7 @@ declare module "mongoose" {
      * Getter/setter around the current mongoose-specific options for this query
      * Below are the current Mongoose-specific options.
      */
-    mongooseOptions(val?: Pick<QueryOptions, "populate" | "lean" | "omitUndefined" | "strict" | "useFindAndModify">): Pick<QueryOptions, "populate" | "lean" | "omitUndefined" | "strict" | "useFindAndModify">;
+    mongooseOptions(val?: MongooseQueryOptions): MongooseQueryOptions;
 
     /** Specifies a `$ne` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     ne(val: any): this;

From c6576632c508bcf2dd2a280137e2d953aa33551d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 13 Dec 2020 12:24:10 -0500
Subject: [PATCH 1510/2348] fix(index.d.ts): support passing a function to
 `ValidateOpts.message`

Fix #9697
---
 index.d.ts | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index e3af0c4c121..96be6e03dc1 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1448,6 +1448,15 @@ declare module "mongoose" {
     unique?: boolean
   }
 
+  interface ValidatorProps {
+    path: string;
+    value: any;
+  }
+
+  interface ValidatorMessageFn {
+    (props: ValidatorProps): string;
+  }
+
   interface ValidateFn<T> {
     (value: T): boolean;
   }
@@ -1462,7 +1471,7 @@ declare module "mongoose" {
 
   interface ValidateOpts<T> {
     msg?: string;
-    message?: string;
+    message?: string | ValidatorMessageFn;
     type?: string;
     validator: ValidateFn<T> | LegacyAsyncValidateFn<T> | AsyncValidateFn<T>;
   }

From d46667af4de2c4fc2ec08c88321efabb3c445d8f Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Mon, 14 Dec 2020 19:56:46 +1100
Subject: [PATCH 1511/2348] fix(css): media query for ::before on headings

Resolves #9704
---
 docs/css/mongoose5.css | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docs/css/mongoose5.css b/docs/css/mongoose5.css
index 2ca3b499b69..c2762493ee6 100644
--- a/docs/css/mongoose5.css
+++ b/docs/css/mongoose5.css
@@ -209,6 +209,12 @@ pre {
 }
 
 @media (max-width: 1160px) {
+  h2:hover::before, h3:hover::before {
+    position: static;
+    display: inline-block;
+    margin-right: .2em;
+  }
+
   .container {
     width: 100%;
     padding: 0px;

From beac486e640d33d5fc5a6b8804ef6f0071ccde5c Mon Sep 17 00:00:00 2001
From: Maneksh <maneksh@Manekshs-MacBook-Pro.local>
Date: Mon, 14 Dec 2020 14:51:53 +0000
Subject: [PATCH 1512/2348] added missing match and model methods in Aggregate
 class in type definition file

---
 index.d.ts | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 96be6e03dc1..dbadf47b89a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2258,6 +2258,18 @@ declare module "mongoose" {
     /** Appends new custom $lookup operator to this aggregate pipeline. */
     lookup(options: any): this;
 
+    /**
+     * Appends a new custom $match operator to this aggregate pipeline.
+     * @param arg $match operator contents
+     */
+    match(arg: any): this;
+
+    /**
+     * Binds this aggregate to a model.
+     * @param model the model to which the aggregate is to be bound
+     */
+    model(model: any): this;
+
     /** Returns the current pipeline */
     pipeline(): any[];
 

From 6fe409afc9e8f2ab8910ba4145a18c0b15a0ec67 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Dec 2020 10:42:12 -0500
Subject: [PATCH 1513/2348] fix(index.d.ts): make options optional for
 `createIndexes()` and `ensureIndexes()`

Fix #9706
---
 index.d.ts | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 96be6e03dc1..80e8c8941ce 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -642,8 +642,7 @@ declare module "mongoose" {
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
      * function.
      */
-    createIndexes(options: any): Promise<void>;
-    createIndexes(options: any, callback?: (err: any) => void): Promise<void>;
+    createIndexes(options?: any, callback?: (err: any) => void): Promise<void>;
 
     /** Connection the model uses. */
     db: Connection;
@@ -666,8 +665,7 @@ declare module "mongoose" {
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
      */
-    ensureIndexes(options: any): Promise<void>;
-    ensureIndexes(options: any, callback?: (err: any) => void): Promise<void>;
+    ensureIndexes(options?: any, callback?: (err: any) => void): Promise<void>;
 
     /**
      * Event emitter that reports any errors that occurred. Useful for global error

From 2f95f9ffa339ddec6c95bee91bb217ba427e2033 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Dec 2020 17:28:39 -0500
Subject: [PATCH 1514/2348] chore: release 5.11.8

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index ef64e41f121..f3cbda38d8f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.11.8 / 2020-12-14
+===================
+ * fix(index.d.ts): add missing single document populate #9696 [YC](https://github.com/YC)
+ * fix(index.d.ts): make options optional for `toObject` #9700
+ * fix(index.d.ts): added missing match and model methods in Aggregate class #9710 [manekshms](https://github.com/manekshms)
+ * fix(index.d.ts): make options optional for `createIndexes()` and `ensureIndexes()` #9706
+ * fix(index.d.ts): support passing a function to `ValidateOpts.message` #9697
+ * docs: add media query for ::before on headings #9705 #9704 [YC](https://github.com/YC)
+
 5.11.7 / 2020-12-10
 ===================
  * fix(document): ensure calling `get()` with empty string returns undefined for mongoose-plugin-autoinc #9681
diff --git a/package.json b/package.json
index a1011f5c6d4..7a7e3a7e27e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.7",
+  "version": "5.11.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a0776ed5cbadb1cfc576ba87c2fc35f035586c43 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 09:24:32 -0500
Subject: [PATCH 1515/2348] fix(index.d.ts): remove `$isSingleNested` from lean
 documents

Re: #9687
---
 index.d.ts | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 96be6e03dc1..ad5f40bde1c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2138,7 +2138,7 @@ declare module "mongoose" {
   type _AllowStringsForIds<T> = {
     [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;
   };
-  export type DocumentDefinition<T> = _AllowStringsForIds<Omit<Omit<T, Exclude<keyof Document, '_id'>>, FunctionPropertyNames<T>>>;
+  export type DocumentDefinition<T> = _AllowStringsForIds<LeanDocument<T>>;
 
   type FunctionPropertyNames<T> = {
     // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
@@ -2162,7 +2162,7 @@ declare module "mongoose" {
     T[K];
   };
 
-  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id'>>, FunctionPropertyNames<T>>;
+  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id'> | '$isSingleNested'>, FunctionPropertyNames<T>>;
 
   export type LeanDocumentOrArray<T> = 0 extends (1 & T) ? T :
     T extends unknown[] ? LeanDocument<T[number]>[] :
@@ -2540,4 +2540,7 @@ declare module "mongoose" {
 
   export type SchemaTypeOpts<T> = SchemaTypeOptions<T>;
   export type ConnectionOptions = ConnectOptions;
+
+  /* for ts-mongoose */
+  class mquery {}
 }

From dc5fc17ad336356fbff7482afbec11b9d10a03a5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 09:27:13 -0500
Subject: [PATCH 1516/2348] fix(index.d.ts): include `__v` in LeanDocuments

Fix #9687
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 0b29fc95178..52d1370c0a6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2160,7 +2160,7 @@ declare module "mongoose" {
     T[K];
   };
 
-  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id'> | '$isSingleNested'>, FunctionPropertyNames<T>>;
+  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id' | '__v'> | '$isSingleNested'>, FunctionPropertyNames<T>>;
 
   export type LeanDocumentOrArray<T> = 0 extends (1 & T) ? T :
     T extends unknown[] ? LeanDocument<T[number]>[] :

From 73badc79a48fcd4648152fac4b88da02142e5bf6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 09:51:34 -0500
Subject: [PATCH 1517/2348] fix(index.d.ts): add missing `Aggregate#append()`

Fix #9714
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 52d1370c0a6..efa813da789 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2214,6 +2214,9 @@ declare module "mongoose" {
     /** Sets the allowDiskUse option for the aggregation query (ignored for < 2.6.0) */
     allowDiskUse(value: boolean): this;
 
+    /** Appends new operators to this aggregate pipeline */
+    append(...args: any[]): this;
+
     /**
      * Executes the query returning a `Promise` which will be
      * resolved with either the doc(s) or rejected with the error.

From c989a15f80b3d19c2aac7d16d39363466cd91b5c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 09:52:47 -0500
Subject: [PATCH 1518/2348] fix(index.d.ts): support calling `createIndexes()`
 and `ensureIndexes()` with just callback

Fix #9706
---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index efa813da789..e1fa327cc08 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -642,6 +642,7 @@ declare module "mongoose" {
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
      * function.
      */
+    createIndexes(callback?: (err: any) => void): Promise<void>;
     createIndexes(options?: any, callback?: (err: any) => void): Promise<void>;
 
     /** Connection the model uses. */
@@ -665,6 +666,7 @@ declare module "mongoose" {
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
      */
+    ensureIndexes(callback?: (err: any) => void): Promise<void>;
     ensureIndexes(options?: any, callback?: (err: any) => void): Promise<void>;
 
     /**

From 43443a28e19f7afb72d7e69503ca8b6dda986f71 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 12:21:21 -0500
Subject: [PATCH 1519/2348] fix(index.d.ts): add missing `Aggregate#unwind()`

---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index e1fa327cc08..517d220fe72 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2317,6 +2317,9 @@ declare module "mongoose" {
      * or a pipeline object.
      */
     sortByCount(arg: string | any): this;
+
+    /** Appends new custom $unwind operator(s) to this aggregate pipeline. */
+    unwind(...args: any[]): this;
   }
 
   class AggregationCursor extends stream.Readable {

From 5ad46bedb55a9b0b248112b8af40648a27b2c8f9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 18:51:58 -0500
Subject: [PATCH 1520/2348] test(populate): repro #9592

---
 test/model.populate.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 454ddaf45e7..4e93ee4984c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9842,4 +9842,31 @@ describe('model: populate:', function() {
       assert.strictEqual(res.child.age, void 0);
     });
   });
+
+  it('avoids propagating lean virtuals to children (gh-9592)', function() {
+    const parentSchema = Schema({
+      child: {
+        type: 'ObjectId',
+        ref: 'Child',
+        populate: { select: 'name' }
+      }
+    });
+    const Parent = db.model('Parent', parentSchema);
+
+    const childSchema = new Schema({ name: String, age: Number });
+    const findCallOptions = [];
+    childSchema.pre('find', function() {
+      findCallOptions.push(this._mongooseOptions.lean);
+    });
+    const Child = db.model('Child', childSchema);
+
+    return co(function*() {
+      const child = yield Child.create({ name: 'my name', age: 30 });
+      yield Parent.create({ child: child._id });
+
+      yield Parent.findOne().populate('child').lean({ virtuals: ['name', 'child.foo'] });
+      assert.equal(findCallOptions.length, 1);
+      assert.deepEqual(findCallOptions[0].virtuals, ['foo']);
+    });
+  });
 });

From ee77df0a286d8b77b38e3a2cf87a1ebab5c50edd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 17 Dec 2020 18:52:24 -0500
Subject: [PATCH 1521/2348] fix(populate): filter lean `virtuals` option to
 avoid mongoose-lean-virtuals setting nested virtuals with same name

Fix #9592
---
 lib/queryhelpers.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index d0e93b65b42..ae274e06092 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -282,6 +282,13 @@ exports.applyPaths = function applyPaths(fields, schema) {
 function makeLean(val) {
   return function(option) {
     option.options || (option.options = {});
+
+    if (val != null && Array.isArray(val.virtuals)) {
+      val.virtuals = val.virtuals.
+        filter(path => typeof path === 'string' && path.startsWith(option.path + '.')).
+        map(path => path.slice(option.path.length + 1));
+    }
+
     option.options.lean = val;
   };
 }

From a5cc3e7a13275978acedae8858523bdb3696b063 Mon Sep 17 00:00:00 2001
From: zce <w@zce.me>
Date: Sat, 19 Dec 2020 21:21:26 +0800
Subject: [PATCH 1522/2348] feat(index.d.ts): schema methods & statics types

---
 index.d.ts                | 38 +++++++++++++++++++++-----------------
 test/typescript/models.ts | 36 +++++++++++++++++++++++++++---------
 2 files changed, 48 insertions(+), 26 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 517d220fe72..0da913fa88d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -241,10 +241,10 @@ declare module "mongoose" {
     models: { [index: string]: Model<any> };
 
     /** Defines or retrieves a model. */
-    model<T extends Document>(name: string, schema?: Schema, collection?: string): Model<T>;
+    model<T extends Document>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
     model<T extends Document, U extends Model<T>>(
       name: string,
-      schema?: Schema,
+      schema?: Schema<T, U>,
       collection?: string,
       skipInit?: boolean
     ): U;
@@ -1026,7 +1026,7 @@ declare module "mongoose" {
     useProjection?: boolean;
   }
 
-  class Schema<T = any> extends events.EventEmitter {
+  class Schema<D extends Document = Document, M extends Model<D> = Model<D>> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1073,11 +1073,13 @@ declare module "mongoose" {
     loadClass(model: Function): this;
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
-    method(name: string, fn: Function, opts?: any): this;
-    method(methods: any): this;
+    method<F extends keyof D>(name: F, fn: D[F]): this;
+    method(obj: { [F in keyof D]: D[F] }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: any;
+    methods: {
+      [F in keyof D]: D[F];
+    };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1098,21 +1100,21 @@ declare module "mongoose" {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = D>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<Document> = M>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = D>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<Document> = M>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Document = D>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<Document> = M>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: any;
@@ -1130,11 +1132,13 @@ declare module "mongoose" {
     set(path: string, value: any, _tags?: any): this;
 
     /** Adds static "class" methods to Models compiled from this schema. */
-    static(name: string, fn: Function): this;
-    static(obj: { [name: string]: Function }): this;
+    static<F extends keyof M>(name: F, fn: M[F]): this;
+    static (obj: { [F in keyof M]: M[F] }): this;
 
     /** Object of currently defined statics on this schema. */
-    statics: any;
+    statics: {
+      [F in keyof M]: M[F];
+    };
 
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;
@@ -2257,7 +2261,7 @@ declare module "mongoose" {
      * @param num maximum number of records to pass to the next stage
      */
     limit(num: number): this;
-                                          
+
     /** Appends new custom $lookup operator to this aggregate pipeline. */
     lookup(options: any): this;
 
@@ -2299,7 +2303,7 @@ declare module "mongoose" {
 
     /** Sets the session for this aggregation. Useful for [transactions](/docs/transactions.html). */
     session(session: mongodb.ClientSession | null): this;
-    
+
     /**
      * Appends a new $skip operator to this aggregate pipeline.
      * @param num number of records to skip before next stage
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 4b4bb75a63f..f80de6a4fe1 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -4,15 +4,15 @@ function conventionalSyntax(): void {
   interface ITest extends Document {
     foo: string;
   }
-  
-  const TestSchema = new Schema({
+
+  const TestSchema = new Schema<ITest>({
     foo: { type: String, required: true },
   });
-  
+
   const Test = connection.model<ITest>('Test', TestSchema);
-  
+
   const bar = (SomeModel: Model<ITest>) => console.log(SomeModel);
-  
+
   bar(Test);
 }
 
@@ -21,8 +21,8 @@ function tAndDocSyntax(): void {
     id: number;
     foo: string;
   }
-  
-  const TestSchema = new Schema({
+
+  const TestSchema = new Schema<ITest & Document>({
     foo: { type: String, required: true },
   });
 
@@ -42,14 +42,32 @@ const ExpiresSchema = new Schema({
 
 interface IProject extends Document {
   name: String;
+  myMethod(): number;
 }
 
 interface ProjectModel extends Model<IProject> {
   myStatic(): number;
 }
 
-const projectSchema: Schema = new Schema({ name: String });
+const projectSchema = new Schema<IProject, ProjectModel>({ name: String });
+
+projectSchema.pre('save', function () {
+  // this => IProject
+});
+
+projectSchema.post('save', function () {
+  // this => IProject
+});
+
+projectSchema.methods.myMethod = () => 10;
+
 projectSchema.statics.myStatic = () => 42;
 
 const Project = connection.model<IProject, ProjectModel>('Project', projectSchema);
-Project.myStatic();
\ No newline at end of file
+Project.myStatic();
+
+Project.create({
+  name: 'mongoose'
+}).then(project => {
+  project.myMethod();
+});
\ No newline at end of file

From b9eeb835e07aa6b46b512e779770b07575cda057 Mon Sep 17 00:00:00 2001
From: zce <w@zce.me>
Date: Sat, 19 Dec 2020 21:34:56 +0800
Subject: [PATCH 1523/2348] feat(index.d.ts): schema methods & statics types

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 0da913fa88d..f6c654708fd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -98,10 +98,10 @@ declare module "mongoose" {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document>(name: string, schema?: Schema, collection?: string, skipInit?: boolean): Model<T>;
+  export function model<T extends Document>(name: string, schema?: Schema<T>, collection?: string, skipInit?: boolean): Model<T>;
   export function model<T extends Document, U extends Model<T>>(
     name: string,
-    schema?: Schema,
+    schema?: Schema<T, U>,
     collection?: string,
     skipInit?: boolean
   ): U;

From e7d2d4b2142872efb3c543158abefd4fc0def2df Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 20 Dec 2020 02:59:50 +0200
Subject: [PATCH 1524/2348] test: add test cases for bulkSave

---
 test/model.test.js | 99 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 5e0fc54d1f5..b9545bfd572 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7054,4 +7054,103 @@ describe('Model', function() {
       });
     });
   });
+
+  describe('bulkSave() (gh-9673)', function() {
+    it('saves new documents', function() {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String }
+        });
+
+        const User = db.model('User', userSchema);
+
+
+        yield User.bulkSave([
+          new User({ name: 'Hafez1_gh-9673-1' }),
+          new User({ name: 'Hafez2_gh-9673-1' })
+        ]);
+
+        const users = yield User.find().sort('name');
+
+        assert.deepEqual(
+          users.map(user => user.name),
+          [
+            'Hafez1_gh-9673-1',
+            'Hafez2_gh-9673-1'
+          ]
+        );
+      });
+    });
+
+    it('updates documents', function() {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String }
+        });
+
+        const User = db.model('User', userSchema);
+
+
+        yield User.insertMany([
+          new User({ name: 'Hafez1_gh-9673-2' }),
+          new User({ name: 'Hafez2_gh-9673-2' })
+        ]);
+
+        const users = yield User.find().sort('name');
+
+        users[0].name = 'Hafez1_gh-9673-2-updated';
+        users[1].name = 'Hafez2_gh-9673-2-updated';
+
+        yield User.bulkSave(users);
+
+        const usersAfterUpdate = yield User.find().sort('name');
+
+        assert.deepEqual(
+          usersAfterUpdate.map(user => user.name),
+          [
+            'Hafez1_gh-9673-2-updated',
+            'Hafez2_gh-9673-2-updated'
+          ]
+        );
+      });
+    });
+    it('changes document state from `isNew` `false` to `true`');
+    it('changes documents state');
+    it('throws an error when a document is invalid');
+    it('throws an error when a document throws a unique error');
+
+    it('throws an error if documents is not an array', function() {
+      const userSchema = new Schema({
+        name: { type: String }
+      });
+
+      const User = db.model('User', userSchema);
+
+
+      assert.throws(
+        function() {
+          User.bulkSave(null);
+        },
+        /bulkSave expects an array of documents to be passed/
+      );
+    });
+    it('throws an error if one element is not a document', function() {
+      const userSchema = new Schema({
+        name: { type: String }
+      });
+
+      const User = db.model('User', userSchema);
+
+
+      assert.throws(
+        function() {
+          User.bulkSave([
+            new User({ name: 'Hafez' }),
+            { name: 'I am not a document' }
+          ]);
+        },
+        /documents\.1 was not a mongoose document/
+      );
+    });
+  });
 });

From e7981f20b92ce82c6b1c0d8c57e89314eb4259fa Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sun, 20 Dec 2020 03:00:07 +0200
Subject: [PATCH 1525/2348] feat(model): base for bulkSave

---
 lib/model.js | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index 4b2e514ccfd..40e118f7846 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3499,6 +3499,46 @@ Model.bulkWrite = function(ops, options, callback) {
   }, this.events);
 };
 
+/**
+ *  takes an array of documents, gets the changes and inserts/updates documents in the database
+ *  according to whether or not the document is new, or whether it has changes or not.
+ *
+ * `bulkSave` uses `bulkWrite` under the hood, so it's mostly useful when dealing with many documents (10K+)
+ *
+ * @param {[Document]} documents
+ *
+ */
+Model.bulkSave = function(documents) {
+  if (!Array.isArray(documents)) {
+    throw new Error(`bulkSave expects an array of documents to be passed, received \`${documents}\` instead`);
+  }
+
+
+  const writeOperations = documents.reduce((accumulator, document, i) => {
+    if (!(document instanceof Document)) {
+      throw new Error(`documents.${i} was not a mongoose document, documents must be an array of mongoose documents (instanceof mongoose.Document).`);
+    }
+
+    const changes = document.getChanges();
+    if (document.isNew) {
+      accumulator.push({
+        insertOne: { document }
+      });
+    } else if (!utils.isEmptyObject(changes)) {
+      accumulator.push({
+        updateOne: {
+          filter: { _id: document._id },
+          update: changes
+        }
+      });
+    }
+
+    return accumulator;
+  }, []);
+
+  return this.bulkWrite(writeOperations);
+};
+
 /**
  * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
  * The document returned has no paths marked as modified initially.

From 4271409eb4465396cb2ea1f3e37b70b88bdf5e83 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 19 Dec 2020 21:16:30 -0500
Subject: [PATCH 1526/2348] fix(index.d.ts): allow `id` paths with non-string
 values in TypeScript

Fix #9723
---
 index.d.ts                                     | 2 +-
 test/typescript/createBasicSchemaDefinition.ts | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 517d220fe72..3df99c8fba2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -475,7 +475,7 @@ declare module "mongoose" {
     getChanges(): UpdateQuery<this>;
 
     /** The string version of this documents _id. */
-    id?: string;
+    id?: any;
 
     /** Signal that we desire an increment of this documents version. */
     increment(): this;
diff --git a/test/typescript/createBasicSchemaDefinition.ts b/test/typescript/createBasicSchemaDefinition.ts
index 3ec8691befb..ac731b1ff60 100644
--- a/test/typescript/createBasicSchemaDefinition.ts
+++ b/test/typescript/createBasicSchemaDefinition.ts
@@ -16,6 +16,7 @@ const schema: Schema = new Schema({
 
 interface ITest extends Document {
   name?: string;
+  id?: number;
   tags?: string[];
   author?: { name: string };
   followers?: { name: string }[];

From 31c1786a3cfddda37e66e8a79da7455d56edb14a Mon Sep 17 00:00:00 2001
From: simon <simon.tretter@hokify.com>
Date: Sun, 20 Dec 2020 16:44:44 +0100
Subject: [PATCH 1527/2348] chore: add eslint ts support

---
 package.json | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 7a7e3a7e27e..78dca9d185f 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,8 @@
   "devDependencies": {
     "@babel/core": "7.10.5",
     "@babel/preset-env": "7.10.4",
+    "@typescript-eslint/eslint-plugin": "^4.10.0",
+    "@typescript-eslint/parser": "^4.10.0",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
@@ -46,7 +48,7 @@
     "cheerio": "1.0.0-rc.2",
     "co": "4.6.0",
     "dox": "0.3.1",
-    "eslint": "7.1.0",
+    "eslint": "^7.1.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.18.2",
     "lodash.isequal": "4.5.0",
@@ -102,9 +104,12 @@
   },
   "eslintConfig": {
     "extends": [
-      "eslint:recommended"
+      "eslint:recommended",
+      "plugin:@typescript-eslint/eslint-recommended",
+      "plugin:@typescript-eslint/recommended"
     ],
     "plugins": [
+      "@typescript-eslint",
       "mocha-no-only"
     ],
     "parserOptions": {

From 68de4651aa17699ae3a1fe070fa18c9ab49a21f9 Mon Sep 17 00:00:00 2001
From: simon <simon.tretter@hokify.com>
Date: Sun, 20 Dec 2020 16:54:19 +0100
Subject: [PATCH 1528/2348] fix: lint index.d.ts

---
 index.d.ts | 123 +++++++++++++++++++++++++++++++----------------------
 1 file changed, 73 insertions(+), 50 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3df99c8fba2..b5e2af77a8d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,4 +1,4 @@
-declare module "mongoose" {
+declare module 'mongoose' {
   import events = require('events');
   import mongodb = require('mongodb');
   import mongoose = require('mongoose');
@@ -35,7 +35,8 @@ declare module "mongoose" {
    * Mongoose constructor. The exports object of the `mongoose` module is an instance of this
    * class. Most apps will only use this one instance.
    */
-  export var Mongoose: new (options?: object | null) => typeof mongoose;
+  // eslint-disable-next-line @typescript-eslint/ban-types
+  export const Mongoose: new (options?: object | null) => typeof mongoose;
 
   /**
    * The Mongoose Number [SchemaType](/docs/schematypes.html). Used for
@@ -52,14 +53,14 @@ declare module "mongoose" {
    */
   export type ObjectId = Schema.Types.ObjectId;
 
-  export var Promise: any;
-  export var PromiseProvider: any;
+  export const Promise: any;
+  export const PromiseProvider: any;
 
   /** The various Mongoose SchemaTypes. */
-  export var SchemaTypes: typeof Schema.Types;
+  export const SchemaTypes: typeof Schema.Types;
 
   /** Expose connection states for user-land */
-  export var STATES: typeof ConnectionStates;
+  export const STATES: typeof ConnectionStates;
 
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
   export function connect(uri: string, options: ConnectOptions, callback: (err: CallbackError) => void): void;
@@ -67,13 +68,13 @@ declare module "mongoose" {
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
 
   /** The Mongoose module's default connection. Equivalent to `mongoose.connections[0]`, see [`connections`](#mongoose_Mongoose-connections). */
-  export var connection: Connection;
+  export const connection: Connection;
 
   /** An array containing all connections associated with this Mongoose instance. */
-  export var connections: Connection[];
+  export const connections: Connection[];
 
   /** An array containing all models associated with this Mongoose instance. */
-  export var models: { [index: string]: Model<any> };
+  export const models: { [index: string]: Model<any> };
   /** Creates a Connection instance. */
   export function createConnection(uri: string, options?: ConnectOptions): Connection & Promise<Connection>;
   export function createConnection(): Connection;
@@ -110,7 +111,7 @@ declare module "mongoose" {
   export function modelNames(): Array<string>;
 
   /** The node-mongodb-native driver Mongoose uses. */
-  export var mongo: typeof mongodb;
+  export const mongo: typeof mongodb;
 
   /**
    * Mongoose uses this function to get the current time when setting
@@ -137,12 +138,13 @@ declare module "mongoose" {
   export function startSession(options: mongodb.SessionOptions, cb: (err: any, session: mongodb.ClientSession) => void): void;
 
   /** The Mongoose version */
-  export var version: string;
+  export const version: string;
 
   export type CastError = Error.CastError;
 
   type Mongoose = typeof mongoose;
 
+  // eslint-disable-next-line @typescript-eslint/no-empty-interface
   interface ClientSession extends mongodb.ClientSession { }
 
   interface ConnectOptions extends mongodb.MongoClientOptions {
@@ -354,6 +356,7 @@ declare module "mongoose" {
      * @param conn A MongooseConnection instance
      * @param opts optional collection options
      */
+    // eslint-disable-next-line @typescript-eslint/no-misused-new
     new(name: string, conn: Connection, opts?: any): Collection;
     /** Formatter for debug print args */
     $format(arg: any): string;
@@ -396,7 +399,7 @@ declare module "mongoose" {
      * is handy for passing data to middleware without conflicting with Mongoose
      * internals.
      */
-    $locals: object;
+    $locals: Record<string, unknown>;
 
     /** Marks a path as valid, removing existing validation errors. */
     $markValid(path: string): void;
@@ -420,7 +423,7 @@ declare module "mongoose" {
     $set(value: any): this;
 
     /** Additional properties to attach to the query when calling `save()` and `isNew` is false. */
-    $where: object;
+    $where: Record<string, unknown>;
 
     /** If this is a discriminator model, `baseModelName` is the name of the base model. */
     baseModelName?: string;
@@ -586,11 +589,13 @@ declare module "mongoose" {
     validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
   }
 
-  export var Model: Model<any>;
+  export const Model: Model<any>;
+  // eslint-disable-next-line no-undef
   interface Model<T extends Document> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
+    // eslint-disable-next-line @typescript-eslint/ban-types
     aggregate<R = any>(pipeline: any[], cb: Function): Promise<Array<R>>;
 
     /** Base Mongoose instance the model uses. */
@@ -673,6 +678,7 @@ declare module "mongoose" {
      * Event emitter that reports any errors that occurred. Useful for global error
      * handling.
      */
+    // eslint-disable-next-line no-undef
     events: NodeJS.EventEmitter;
 
     /**
@@ -733,14 +739,14 @@ declare module "mongoose" {
      * the model's schema except the `_id` index, and build any indexes that
      * are in your schema but not in MongoDB.
      */
-    syncIndexes(options?: object): Promise<Array<string>>;
-    syncIndexes(options: object | null, callback: (err: CallbackError, dropped: Array<string>) => void): void;
+    syncIndexes(options?: Record<string, unknown>): Promise<Array<string>>;
+    syncIndexes(options: Record<string, unknown> | null, callback: (err: CallbackError, dropped: Array<string>) => void): void;
 
     /**
      * Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
      * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
      * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
-     **/
+     * */
     startSession(options?: mongodb.SessionOptions, cb?: (err: any, session: mongodb.ClientSession) => void): Promise<mongodb.ClientSession>;
 
     /** Casts and validates the given object against this model's schema, passing the given `context` to custom validators. */
@@ -748,9 +754,10 @@ declare module "mongoose" {
     validate(optional: any, callback?: (err: any) => void): Promise<void>;
 
     /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
-    watch(pipeline?: Array<object>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
+    watch(pipeline?: Array<Record<string, unknown>>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
 
     /** Adds a `$where` clause to this query */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     $where(argument: string | Function): Query<Array<T>, T>;
 
     /** Registered discriminators for this model. */
@@ -820,10 +827,6 @@ declare module "mongoose" {
     /** Schema the model uses. */
     schema: Schema;
 
-    /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
-
     /** Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option. */
     update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
 
@@ -896,7 +899,7 @@ declare module "mongoose" {
     writeConcern?: any;
   }
 
-  type MongooseQueryOptions = Pick<QueryOptions, "populate" | "lean" | "omitUndefined" | "strict" | "useFindAndModify">;
+  type MongooseQueryOptions = Pick<QueryOptions, 'populate' | 'lean' | 'omitUndefined' | 'strict' | 'useFindAndModify'>;
 
   interface SaveOptions {
     checkKeys?: boolean;
@@ -933,6 +936,7 @@ declare module "mongoose" {
   }
 
   interface MapReduceOptions<T, Key, Val> {
+    // eslint-disable-next-line @typescript-eslint/ban-types
     map: Function | string;
     reduce: (key: Key, vals: T[]) => Val;
     /** query filter object. */
@@ -1070,9 +1074,11 @@ declare module "mongoose" {
      * [statics](http://mongoosejs.com/docs/guide.html#statics), and
      * [methods](http://mongoosejs.com/docs/guide.html#methods).
      */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     loadClass(model: Function): this;
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     method(name: string, fn: Function, opts?: any): this;
     method(methods: any): this;
 
@@ -1098,21 +1104,21 @@ declare module "mongoose" {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = Document>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<any> = Model<any>>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = Document>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<any> = Model<any>>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = Document>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Document = Document>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<any> = Model<any>>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<any> = Model<any>>(method: 'insertMany' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: any;
@@ -1130,7 +1136,9 @@ declare module "mongoose" {
     set(path: string, value: any, _tags?: any): this;
 
     /** Adds static "class" methods to Models compiled from this schema. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     static(name: string, fn: Function): this;
+    // eslint-disable-next-line @typescript-eslint/ban-types
     static(obj: { [name: string]: Function }): this;
 
     /** Object of currently defined statics on this schema. */
@@ -1147,6 +1155,7 @@ declare module "mongoose" {
   }
 
   interface SchemaDefinition {
+    // eslint-disable-next-line @typescript-eslint/ban-types
     [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[] | SchemaDefinition | SchemaDefinition[];
   }
 
@@ -1231,17 +1240,17 @@ declare module "mongoose" {
      * given a shard key which must be present in all insert/update operations. We just need to set this
      * schema option to the same shard key and we'll be all set.
      */
-    shardKey?: object;
+    shardKey?: Record<string, unknown>;
     /**
      * For backwards compatibility, the strict option does not apply to the filter parameter for queries.
      * Mongoose has a separate strictQuery option to toggle strict mode for the filter parameter to queries.
      */
-    strictQuery?: boolean | "throw";
+    strictQuery?: boolean | 'throw';
     /**
      * The strict option, (enabled by default), ensures that values passed to our model constructor that were not
      * specified in our schema do not get saved to the db.
      */
-    strict?: boolean | "throw";
+    strict?: boolean | 'throw';
     /** Exactly the same as the toObject option but only applies when the document's toJSON method is called. */
     toJSON?: ToObjectOptions;
     /**
@@ -1319,7 +1328,8 @@ declare module "mongoose" {
     alias?: string;
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    validate?: RegExp | [RegExp, string] | Function | [Function , string] | ValidateOpts<T> | ValidateOpts<T>[];
+    // eslint-disable-next-line @typescript-eslint/ban-types
+    validate?: RegExp | [RegExp, string] | Function | [Function, string] | ValidateOpts<T> | ValidateOpts<T>[];
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
     cast?: string;
@@ -1414,6 +1424,7 @@ declare module "mongoose" {
     _id?: boolean;
 
     /** If set, specifies the type of this map's values. Mongoose will cast this map's values to the given type. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     of?: Function | SchemaTypeOptions<any>;
 
     /** If true, uses Mongoose's default `_id` settings. Only allowed for ObjectIds */
@@ -1483,8 +1494,10 @@ declare module "mongoose" {
     applySetters(value: any, doc: Document): any;
 
     /** Adds a custom getter to this virtual. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     get(fn: Function): this;
     /** Adds a custom setter to this virtual. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     set(fn: Function): this;
   }
 
@@ -1722,6 +1735,7 @@ declare module "mongoose" {
 
     // var objectId: mongoose.Types.ObjectId should reference mongodb.ObjectID not
     //   the ObjectIdConstructor, so we add the interface below
+    // eslint-disable-next-line @typescript-eslint/no-empty-interface
     interface ObjectId extends mongodb.ObjectID { }
 
     class Subdocument extends Document {
@@ -1738,9 +1752,13 @@ declare module "mongoose" {
   interface Query<ResultType, DocType extends Document> {
     _mongooseOptions: MongooseQueryOptions;
 
+    /** Executes the query */
     exec(): Promise<ResultType>;
     exec(callback?: (err: CallbackError, res: ResultType) => void): void;
+    // @todo: this doesn't seem right
+    exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
 
+    // eslint-disable-next-line @typescript-eslint/ban-types
     $where(argument: string | Function): Query<Array<DocType>, DocType>;
 
     /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
@@ -1764,7 +1782,7 @@ declare module "mongoose" {
      * resolved with either the doc(s) or rejected with the error.
      * Like `.then()`, but only takes a rejection handler.
      */
-    catch: Promise<ResultType>["catch"];
+    catch: Promise<ResultType>['catch'];
 
     /** Specifies a `$center` or `$centerSphere` condition. */
     circle(area: any): this;
@@ -1808,7 +1826,9 @@ declare module "mongoose" {
     distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     elemMatch(val: Function | any): this;
+    // eslint-disable-next-line @typescript-eslint/ban-types
     elemMatch(path: string, val: Function | any): this;
 
     /**
@@ -1824,9 +1844,6 @@ declare module "mongoose" {
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
     estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType>;
 
-    /** Executes the query */
-    exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
-
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
     exists(path: string, val: boolean): this;
@@ -2078,7 +2095,7 @@ declare module "mongoose" {
      * Executes the query returning a `Promise` which will be
      * resolved with either the doc(s) or rejected with the error.
      */
-    then: Promise<ResultType>["then"];
+    then: Promise<ResultType>['then'];
 
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
     toConstructor(): new (...args: any[]) => Query<ResultType, DocType>;
@@ -2142,12 +2159,14 @@ declare module "mongoose" {
 
   type FunctionPropertyNames<T> = {
     // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
+    // eslint-disable-next-line @typescript-eslint/ban-types
     [K in keyof T]: 0 extends (1 & T[K]) ? never : (T[K] extends Function ? K : never)
   }[keyof T];
 
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
   type TreatAsPrimitives = actualPrimitives |
-    Date | RegExp | Symbol | Error | BigInt | Types.ObjectId;
+      // eslint-disable-next-line no-undef
+    Date | RegExp | symbol | Error | BigInt | Types.ObjectId;
 
   type LeanType<T> =
     0 extends (1 & T) ? T : // any
@@ -2224,7 +2243,7 @@ declare module "mongoose" {
      * resolved with either the doc(s) or rejected with the error.
      * Like [`.then()`](#query_Query-then), but only takes a rejection handler.
      */
-    catch: Promise<R>["catch"];
+    catch: Promise<R>['catch'];
 
     /** Adds a collation. */
     collation(options: mongodb.CollationDocument): this;
@@ -2235,7 +2254,7 @@ declare module "mongoose" {
     /**
      * Sets the cursor option option for the aggregation query (ignored for < 2.6.0).
      */
-    cursor(options?: object): this;
+    cursor(options?: Record<string, unknown>): this;
 
     /** Executes the aggregate pipeline on the currently bound Model. If cursor option is set, returns a cursor */
     exec(callback?: (err: any, result: R) => void): Promise<R> | any;
@@ -2250,14 +2269,14 @@ declare module "mongoose" {
     graphLookup(options: any): this;
 
     /** Sets the hint option for the aggregation query (ignored for < 3.6.0) */
-    hint(value: object | string): this;
+    hint(value: Record<string, unknown> | string): this;
 
     /**
      * Appends a new $limit operator to this aggregate pipeline.
      * @param num maximum number of records to pass to the next stage
      */
     limit(num: number): this;
-                                          
+
     /** Appends new custom $lookup operator to this aggregate pipeline. */
     lookup(options: any): this;
 
@@ -2292,14 +2311,14 @@ declare module "mongoose" {
     search(options: any): this;
 
     /** Lets you set arbitrary options, for middleware or plugins. */
-    option(value: object): this;
+    option(value: Record<string, unknown>): this;
 
     /** Appends new custom $sample operator to this aggregate pipeline. */
     sample(size: number): this;
 
     /** Sets the session for this aggregation. Useful for [transactions](/docs/transactions.html). */
     session(session: mongodb.ClientSession | null): this;
-    
+
     /**
      * Appends a new $skip operator to this aggregate pipeline.
      * @param num number of records to skip before next stage
@@ -2310,7 +2329,7 @@ declare module "mongoose" {
     sort(arg: any): this;
 
     /** Provides promise for aggregate. */
-    then: Promise<R>["then"];
+    then: Promise<R>['then'];
 
     /**
      * Appends a new $sortByCount operator to this aggregate pipeline. Accepts either a string field name
@@ -2363,6 +2382,7 @@ declare module "mongoose" {
     constructor(path: string, options?: any, instance?: string);
 
     /** Get/set the function used to cast arbitrary values to this type. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     static cast(caster?: Function | boolean): Function;
 
     static checkRequired(checkRequired?: (v: any) => boolean): (v: any) => boolean;
@@ -2380,6 +2400,7 @@ declare module "mongoose" {
     default(val: any): any;
 
     /** Adds a getter to this schematype. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     get(fn: Function): this;
 
     /**
@@ -2407,6 +2428,7 @@ declare module "mongoose" {
     select(val: boolean): this;
 
     /** Adds a setter to this schematype. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     set(fn: Function): this;
 
     /** Declares a sparse index. */
@@ -2422,6 +2444,7 @@ declare module "mongoose" {
     unique(bool: boolean): this;
 
     /** Adds validator(s) for this document path. */
+    // eslint-disable-next-line @typescript-eslint/ban-types
     validate(obj: RegExp | Function | any, errorMsg?: string,
       type?: string): this;
   }
@@ -2440,7 +2463,7 @@ declare module "mongoose" {
     static Messages: any;
   }
 
-  module Error {
+  namespace Error {
     export class CastError extends Error {
       name: 'CastError';
       stringValue: string;

From 1bb4a30fdd9bb87f74ffe4db8957b20c8cdb93f8 Mon Sep 17 00:00:00 2001
From: simon <simon.tretter@hokify.com>
Date: Mon, 21 Dec 2020 08:59:09 +0100
Subject: [PATCH 1529/2348] chore: only use ts linting config for ts and tsx
 files

---
 package.json | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/package.json b/package.json
index 78dca9d185f..084487f8c36 100644
--- a/package.json
+++ b/package.json
@@ -104,12 +104,23 @@
   },
   "eslintConfig": {
     "extends": [
-      "eslint:recommended",
-      "plugin:@typescript-eslint/eslint-recommended",
-      "plugin:@typescript-eslint/recommended"
+      "eslint:recommended"
     ],
+    "overrides": [
+      {
+        "files": [
+          "**/*.{ts,tsx}"
+        ],
+        "extends": [
+          "plugin:@typescript-eslint/eslint-recommended",
+          "plugin:@typescript-eslint/recommended"
+        ],
+        "plugins": [
+          "@typescript-eslint"
+        ]
+      }
+      ],
     "plugins": [
-      "@typescript-eslint",
       "mocha-no-only"
     ],
     "parserOptions": {

From e5d2cd0322fb38b13e6e3d588601cb1c29a823bd Mon Sep 17 00:00:00 2001
From: simon <simon.tretter@hokify.com>
Date: Mon, 21 Dec 2020 10:25:06 +0100
Subject: [PATCH 1530/2348] lint: lint all test files

---
 test/docs/custom-casting.test.js    |  6 +-
 test/docs/date.test.js              |  6 +-
 test/docs/defaults.test.js          | 10 ++--
 test/docs/discriminators.test.js    | 85 +++++++++++++++--------------
 test/docs/promises.test.js          | 46 ++++++++--------
 test/docs/schemas.test.js           |  4 +-
 test/docs/schematypes.test.js       |  4 +-
 test/docs/validation.test.js        | 12 ++--
 test/typescript/aggregate.ts        |  8 +--
 test/typescript/base.ts             |  8 +--
 test/typescript/collection.ts       | 10 ++--
 test/typescript/connectSyntax.ts    |  4 +-
 test/typescript/discriminator.ts    | 28 +++++-----
 test/typescript/methods.ts          |  6 +-
 test/typescript/middleware.ts       |  3 +-
 test/typescript/modelInheritance.ts |  4 +-
 test/typescript/models.ts           | 22 ++++----
 test/typescript/queries.ts          |  4 +-
 test/typescript/querycursor.ts      |  4 +-
 test/typescript/subdocuments.ts     |  8 +--
 20 files changed, 142 insertions(+), 140 deletions(-)

diff --git a/test/docs/custom-casting.test.js b/test/docs/custom-casting.test.js
index e55d02da9bf..bd9d8484702 100644
--- a/test/docs/custom-casting.test.js
+++ b/test/docs/custom-casting.test.js
@@ -10,7 +10,7 @@ describe('custom casting', function() {
 
   beforeEach(function() {
     originalCast = mongoose.Number.cast();
-  })
+  });
 
   afterEach(function() {
     mongoose.deleteModel('Test');
@@ -60,5 +60,5 @@ describe('custom casting', function() {
     assert.ifError(err);
     assert.equal(doc.age, 2);
     // acquit:ignore:end
-  });  
-});
\ No newline at end of file
+  });
+});
diff --git a/test/docs/date.test.js b/test/docs/date.test.js
index 14ffdbca98b..de689f69ce2 100644
--- a/test/docs/date.test.js
+++ b/test/docs/date.test.js
@@ -6,7 +6,7 @@ const start = require('../common');
 
 describe('Date Tutorial', function() {
   let User;
-  let db;
+  // let db;
 
   const mongoose = new start.mongoose.Mongoose();
 
@@ -43,7 +43,7 @@ describe('Date Tutorial', function() {
     user.validateSync().errors['lastActiveAt']; // CastError
     // acquit:ignore:start
     assert.ok(!(user.lastActiveAt instanceof Date));
-    assert.equal(user.validateSync().errors['lastActiveAt'].name, 'CastError')
+    assert.equal(user.validateSync().errors['lastActiveAt'].name, 'CastError');
     // acquit:ignore:end
   });
 
@@ -159,4 +159,4 @@ describe('Date Tutorial', function() {
     assert.equal(user.lastActiveAt.toISOString(), '2019-03-10T23:44:56.289Z');
     // acquit:ignore:end
   });
-});
\ No newline at end of file
+});
diff --git a/test/docs/defaults.test.js b/test/docs/defaults.test.js
index b92cf4cf307..05c4bba9dff 100644
--- a/test/docs/defaults.test.js
+++ b/test/docs/defaults.test.js
@@ -3,7 +3,7 @@
 const assert = require('assert');
 const mongoose = require('../../');
 
-describe('defaults docs', function () {
+describe('defaults docs', function() {
   let db;
   const Schema = mongoose.Schema;
 
@@ -76,7 +76,7 @@ describe('defaults docs', function () {
 
     const BlogPost = db.model('BlogPost', schema);
 
-    const post = new BlogPost({title: '5 Best Arnold Schwarzenegger Movies'});
+    const post = new BlogPost({ title: '5 Best Arnold Schwarzenegger Movies' });
 
     // The post has a default Date set to now
     assert.ok(post.date.getTime() >= Date.now() - 1000);
@@ -99,13 +99,13 @@ describe('defaults docs', function () {
   it('The `setDefaultsOnInsert` option', function(done) {
     const schema = new Schema({
       title: String,
-      genre: {type: String, default: 'Action'}
+      genre: { type: String, default: 'Action' }
     });
 
     const Movie = db.model('Movie', schema);
 
     const query = {};
-    const update = {title: 'The Terminator'};
+    const update = { title: 'The Terminator' };
     const options = {
       // Return the document after updates are applied
       new: true,
@@ -116,7 +116,7 @@ describe('defaults docs', function () {
     };
 
     Movie.
-      findOneAndUpdate(query, update, options, function (error, doc) {
+      findOneAndUpdate(query, update, options, function(error, doc) {
         assert.ifError(error);
         assert.equal(doc.title, 'The Terminator');
         assert.equal(doc.genre, 'Action');
diff --git a/test/docs/discriminators.test.js b/test/docs/discriminators.test.js
index 5c9793e93e4..e05c186a1cf 100644
--- a/test/docs/discriminators.test.js
+++ b/test/docs/discriminators.test.js
@@ -5,28 +5,28 @@ const mongoose = require('../../');
 
 const Schema = mongoose.Schema;
 
-describe('discriminator docs', function () {
+describe('discriminator docs', function() {
   let Event;
   let ClickedLinkEvent;
   let SignedUpEvent;
   let db;
 
-  before(function (done) {
+  before(function(done) {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
 
-    const eventSchema = new mongoose.Schema({time: Date});
+    const eventSchema = new mongoose.Schema({ time: Date });
     Event = db.model('_event', eventSchema);
 
     ClickedLinkEvent = Event.discriminator('ClickedLink',
-      new mongoose.Schema({url: String}));
+      new mongoose.Schema({ url: String }));
 
     SignedUpEvent = Event.discriminator('SignedUp',
-      new mongoose.Schema({username: String}));
+      new mongoose.Schema({ username: String }));
 
     done();
   });
 
-  after(function (done) {
+  after(function(done) {
     db.close(done);
   });
 
@@ -47,24 +47,24 @@ describe('discriminator docs', function () {
    * key (defaults to the model name). It returns a model whose schema
    * is the union of the base schema and the discriminator schema.
    */
-  it('The `model.discriminator()` function', function (done) {
-    const options = {discriminatorKey: 'kind'};
+  it('The `model.discriminator()` function', function(done) {
+    const options = { discriminatorKey: 'kind' };
 
-    const eventSchema = new mongoose.Schema({time: Date}, options);
+    const eventSchema = new mongoose.Schema({ time: Date }, options);
     const Event = mongoose.model('Event', eventSchema);
 
     // ClickedLinkEvent is a special type of Event that has
     // a URL.
     const ClickedLinkEvent = Event.discriminator('ClickedLink',
-      new mongoose.Schema({url: String}, options));
+      new mongoose.Schema({ url: String }, options));
 
     // When you create a generic event, it can't have a URL field...
-    const genericEvent = new Event({time: Date.now(), url: 'google.com'});
+    const genericEvent = new Event({ time: Date.now(), url: 'google.com' });
     assert.ok(!genericEvent.url);
 
     // But a ClickedLinkEvent can
     const clickedEvent =
-      new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
+      new ClickedLinkEvent({ time: Date.now(), url: 'google.com' });
     assert.ok(clickedEvent.url);
 
     // acquit:ignore:start
@@ -78,16 +78,17 @@ describe('discriminator docs', function () {
    * stored in the same collection as generic events and `ClickedLinkEvent`
    * instances.
    */
-  it('Discriminators save to the Event model\'s collection', function (done) {
-    const event1 = new Event({time: Date.now()});
-    const event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
-    const event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
-
-    const save = function (doc, callback) {
-      doc.save(function (error, doc) {
+  it('Discriminators save to the Event model\'s collection', function(done) {
+    const event1 = new Event({ time: Date.now() });
+    const event2 = new ClickedLinkEvent({ time: Date.now(), url: 'google.com' });
+    const event3 = new SignedUpEvent({ time: Date.now(), user: 'testuser' });
+
+    /*
+    const save = function(doc, callback) {
+      doc.save(function(error, doc) {
         callback(error, doc);
       });
-    };
+    }; */
 
     Promise.all([event1.save(), event2.save(), event3.save()]).
       then(() => Event.countDocuments()).
@@ -106,10 +107,10 @@ describe('discriminator docs', function () {
    * to your schemas that it uses to track which discriminator
    * this document is an instance of.
    */
-  it('Discriminator keys', function (done) {
-    const event1 = new Event({time: Date.now()});
-    const event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
-    const event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
+  it('Discriminator keys', function(done) {
+    const event1 = new Event({ time: Date.now() });
+    const event2 = new ClickedLinkEvent({ time: Date.now(), url: 'google.com' });
+    const event3 = new SignedUpEvent({ time: Date.now(), user: 'testuser' });
 
     assert.ok(!event1.__t);
     assert.equal(event2.__t, 'ClickedLink');
@@ -125,10 +126,10 @@ describe('discriminator docs', function () {
    * to queries. In other words, `find()`, `count()`, `aggregate()`, etc.
    * are smart enough to account for discriminators.
    */
-  it('Discriminators add the discriminator key to queries', function (done) {
-    const event1 = new Event({time: Date.now()});
-    const event2 = new ClickedLinkEvent({time: Date.now(), url: 'google.com'});
-    const event3 = new SignedUpEvent({time: Date.now(), user: 'testuser'});
+  it('Discriminators add the discriminator key to queries', function(done) {
+    const event1 = new Event({ time: Date.now() });
+    const event2 = new ClickedLinkEvent({ time: Date.now(), url: 'google.com' });
+    const event3 = new SignedUpEvent({ time: Date.now(), user: 'testuser' });
 
     Promise.all([event1.save(), event2.save(), event3.save()]).
       then(() => ClickedLinkEvent.find({})).
@@ -147,20 +148,20 @@ describe('discriminator docs', function () {
    * However, you can also attach middleware to the discriminator schema
    * without affecting the base schema.
    */
-  it('Discriminators copy pre and post hooks', function (done) {
-    const options = {discriminatorKey: 'kind'};
+  it('Discriminators copy pre and post hooks', function(done) {
+    const options = { discriminatorKey: 'kind' };
 
-    const eventSchema = new mongoose.Schema({time: Date}, options);
+    const eventSchema = new mongoose.Schema({ time: Date }, options);
     let eventSchemaCalls = 0;
-    eventSchema.pre('validate', function (next) {
+    eventSchema.pre('validate', function(next) {
       ++eventSchemaCalls;
       next();
     });
     const Event = mongoose.model('GenericEvent', eventSchema);
 
-    const clickedLinkSchema = new mongoose.Schema({url: String}, options);
+    const clickedLinkSchema = new mongoose.Schema({ url: String }, options);
     let clickedSchemaCalls = 0;
-    clickedLinkSchema.pre('validate', function (next) {
+    clickedLinkSchema.pre('validate', function(next) {
       ++clickedSchemaCalls;
       next();
     });
@@ -190,11 +191,11 @@ describe('discriminator docs', function () {
    * If a custom _id field is set on the base schema, that will always
    * override the discriminator's _id field, as shown below.
    */
-  it('Handling custom _id fields', function (done) {
-    const options = {discriminatorKey: 'kind'};
+  it('Handling custom _id fields', function(done) {
+    const options = { discriminatorKey: 'kind' };
 
     // Base schema has a custom String `_id` and a Date `time`...
-    const eventSchema = new mongoose.Schema({_id: String, time: Date},
+    const eventSchema = new mongoose.Schema({ _id: String, time: Date },
       options);
     const Event = mongoose.model('BaseEvent', eventSchema);
 
@@ -209,7 +210,7 @@ describe('discriminator docs', function () {
     const ClickedLinkEvent = Event.discriminator('ChildEventBad',
       clickedLinkSchema);
 
-    const event1 = new ClickedLinkEvent({_id: 'custom id', time: '4pm'});
+    const event1 = new ClickedLinkEvent({ _id: 'custom id', time: '4pm' });
     // clickedLinkSchema overwrites the `time` path, but **not**
     // the `_id` path.
     assert.strictEqual(typeof event1._id, 'string');
@@ -345,7 +346,7 @@ describe('discriminator docs', function () {
     const eventListSchema = new Schema({ events: [singleEventSchema] });
 
     const subEventSchema = new Schema({
-       sub_events: [singleEventSchema]
+      sub_events: [singleEventSchema]
     }, { _id: false });
 
     const SubEvent = subEventSchema.path('sub_events').
@@ -357,8 +358,8 @@ describe('discriminator docs', function () {
     // Create a new batch of events with different kinds
     const list = {
       events: [
-        { kind: 'SubEvent', sub_events: [{kind:'SubEvent', sub_events:[], message:'test1'}], message: 'hello' },
-        { kind: 'SubEvent', sub_events: [{kind:'SubEvent', sub_events:[{kind:'SubEvent', sub_events:[], message:'test3'}], message:'test2'}], message: 'world' }
+        { kind: 'SubEvent', sub_events: [{ kind: 'SubEvent', sub_events: [], message: 'test1' }], message: 'hello' },
+        { kind: 'SubEvent', sub_events: [{ kind: 'SubEvent', sub_events: [{ kind: 'SubEvent', sub_events: [], message: 'test3' }], message: 'test2' }], message: 'world' }
       ]
     };
 
@@ -374,7 +375,7 @@ describe('discriminator docs', function () {
         assert.equal(doc.events[1].message, 'world');
         assert.ok(doc.events[1].sub_events[0].sub_events[0] instanceof SubEvent);
 
-        doc.events.push({kind:'SubEvent', sub_events:[{kind:'SubEvent', sub_events:[], message:'test4'}], message:'pushed'});
+        doc.events.push({ kind: 'SubEvent', sub_events: [{ kind: 'SubEvent', sub_events: [], message: 'test4' }], message: 'pushed' });
         return doc.save();
       }).
       then(function(doc) {
diff --git a/test/docs/promises.test.js b/test/docs/promises.test.js
index c26b2a26e5e..6a76d3691cf 100644
--- a/test/docs/promises.test.js
+++ b/test/docs/promises.test.js
@@ -1,25 +1,25 @@
 'use strict';
-const PromiseProvider = require('../../lib/promise_provider');
+// const PromiseProvider = require('../../lib/promise_provider');
 const assert = require('assert');
 const mongoose = require('../../');
 
-describe('promises docs', function () {
+describe('promises docs', function() {
   let Band;
   let db;
 
-  before(function (done) {
+  before(function(done) {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
 
-    Band = db.model('band-promises', {name: String, members: [String]});
+    Band = db.model('band-promises', { name: String, members: [String] });
 
     done();
   });
 
-  beforeEach(function (done) {
+  beforeEach(function(done) {
     Band.deleteMany({}, done);
   });
 
-  after(function (done) {
+  after(function(done) {
     db.close(done);
   });
 
@@ -28,21 +28,21 @@ describe('promises docs', function () {
    * This means that you can do things like `MyModel.findOne({}).then()` and
    * `await MyModel.findOne({}).exec()` if you're using
    * [async/await](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html).
-   * 
+   *
    * You can find the return type of specific operations [in the api docs](https://mongoosejs.com/docs/api.html)
    * You can also read more about [promises in Mongoose](https://masteringjs.io/tutorials/mongoose/promise).
    */
-  it('Built-in Promises', function (done) {
+  it('Built-in Promises', function(done) {
     const gnr = new Band({
-      name: "Guns N' Roses",
+      name: 'Guns N\' Roses',
       members: ['Axl', 'Slash']
     });
 
     const promise = gnr.save();
     assert.ok(promise instanceof Promise);
 
-    promise.then(function (doc) {
-      assert.equal(doc.name, "Guns N' Roses");
+    promise.then(function(doc) {
+      assert.equal(doc.name, 'Guns N\' Roses');
       // acquit:ignore:start
       done();
       // acquit:ignore:end
@@ -55,8 +55,8 @@ describe('promises docs', function () {
    * a convenience. If you need
    * a fully-fledged promise, use the `.exec()` function.
    */
-  it('Queries are not promises', function (done) {
-    const query = Band.findOne({name: "Guns N' Roses"});
+  it('Queries are not promises', function(done) {
+    const query = Band.findOne({ name: 'Guns N\' Roses' });
     assert.ok(!(query instanceof Promise));
 
     // acquit:ignore:start
@@ -64,7 +64,7 @@ describe('promises docs', function () {
     // acquit:ignore:end
 
     // A query is not a fully-fledged promise, but it does have a `.then()`.
-    query.then(function (doc) {
+    query.then(function(doc) {
       // use doc
       // acquit:ignore:start
       assert.ok(!doc);
@@ -76,7 +76,7 @@ describe('promises docs', function () {
     const promise = query.exec();
     assert.ok(promise instanceof Promise);
 
-    promise.then(function (doc) {
+    promise.then(function(doc) {
       // use doc
       // acquit:ignore:start
       assert.ok(!doc);
@@ -90,8 +90,8 @@ describe('promises docs', function () {
    * That means they have a `.then()` function, so you can use queries as promises with either
    * promise chaining or [async await](https://asyncawait.net)
    */
-  it('Queries are thenable', function (done) {
-    Band.findOne({name: "Guns N' Roses"}).then(function(doc) {
+  it('Queries are thenable', function(done) {
+    Band.findOne({ name: 'Guns N\' Roses' }).then(function(doc) {
       // use doc
       // acquit:ignore:start
       assert.ok(!doc);
@@ -102,31 +102,31 @@ describe('promises docs', function () {
 
   /**
    * There are two alternatives for using `await` with queries:
-   * 
+   *
    * - `await Band.findOne();`
    * - `await Band.findOne().exec();`
-   * 
+   *
    * As far as functionality is concerned, these two are equivalent.
    * However, we recommend using `.exec()` because that gives you
    * better stack traces.
    */
   it('Should You Use `exec()` With `await`?', function() {
-    
+
   });
-  
+
   /**
    * If you're an advanced user, you may want to plug in your own promise
    * library like [bluebird](https://www.npmjs.com/package/bluebird). Just set
    * `mongoose.Promise` to your favorite
    * ES6-style promise constructor and mongoose will use it.
    */
-  it('Plugging in your own Promises Library', function (done) {
+  it('Plugging in your own Promises Library', function(done) {
     // acquit:ignore:start
     if (!global.Promise) {
       return done();
     }
     // acquit:ignore:end
-    const query = Band.findOne({name: "Guns N' Roses"});
+    const query = Band.findOne({ name: 'Guns N\' Roses' });
 
     // Use bluebird
     mongoose.Promise = require('bluebird');
diff --git a/test/docs/schemas.test.js b/test/docs/schemas.test.js
index 8ae5ed59866..a2cad4f8c0e 100644
--- a/test/docs/schemas.test.js
+++ b/test/docs/schemas.test.js
@@ -3,9 +3,9 @@
 const assert = require('assert');
 const mongoose = require('../../');
 
-describe('Advanced Schemas', function () {
+describe('Advanced Schemas', function() {
   let db;
-  let Schema = mongoose.Schema;
+  const Schema = mongoose.Schema;
 
   before(function() {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
diff --git a/test/docs/schematypes.test.js b/test/docs/schematypes.test.js
index 77d32d9abf9..f3e454969b9 100644
--- a/test/docs/schematypes.test.js
+++ b/test/docs/schematypes.test.js
@@ -2,9 +2,9 @@
 const assert = require('assert');
 const mongoose = require('../../');
 
-describe('schemaTypes', function () {
+describe('schemaTypes', function() {
   let db;
-  let Schema = mongoose.Schema;
+  const Schema = mongoose.Schema;
 
   before(function() {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test');
diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 7e904526aa5..50d1268c9df 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -6,7 +6,7 @@ const Promise = global.Promise || require('bluebird');
 
 describe('validation docs', function() {
   let db;
-  let Schema = mongoose.Schema;
+  const Schema = mongoose.Schema;
 
   before(function() {
     db = mongoose.createConnection('mongodb://localhost:27017/mongoose_test', {
@@ -280,7 +280,7 @@ describe('validation docs', function() {
 
     const toy = new Toy({ color: 'Green', name: 'Power Ranger' });
 
-    toy.save(function (err) {
+    toy.save(function(err) {
       // `err` is a ValidationError object
       // `err.errors.color` is a ValidatorError object
       assert.equal(err.errors.color.message, 'Color `Green` not valid');
@@ -399,12 +399,12 @@ describe('validation docs', function() {
 
     const Toy = db.model('Toys', toySchema);
 
-    Toy.schema.path('color').validate(function (value) {
+    Toy.schema.path('color').validate(function(value) {
       return /red|green|blue/i.test(value);
     }, 'Invalid color');
 
     const opts = { runValidators: true };
-    Toy.updateOne({}, { color: 'not a color' }, opts, function (err) {
+    Toy.updateOne({}, { color: 'not a color' }, opts, function(err) {
       assert.equal(err.errors.color.message,
         'Invalid color');
       // acquit:ignore:start
@@ -517,7 +517,7 @@ describe('validation docs', function() {
 
     const update = { color: 'blue' };
     const opts = { runValidators: true };
-    Kitten.updateOne({}, update, opts, function(err) {
+    Kitten.updateOne({}, update, opts, function() {
       // Operation succeeds despite the fact that 'name' is not specified
       // acquit:ignore:start
       --outstanding || done();
@@ -570,7 +570,7 @@ describe('validation docs', function() {
 
     let update = { $inc: { number: 1 } };
     const opts = { runValidators: true };
-    Test.updateOne({}, update, opts, function(error) {
+    Test.updateOne({}, update, opts, function() {
       // There will never be a validation error here
       update = { $push: [{ message: 'hello' }, { message: 'world' }] };
       Test.updateOne({}, update, opts, function(error) {
diff --git a/test/typescript/aggregate.ts b/test/typescript/aggregate.ts
index 9bcc1d12224..ec8a9096c8f 100644
--- a/test/typescript/aggregate.ts
+++ b/test/typescript/aggregate.ts
@@ -17,13 +17,13 @@ Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).then((res: Array<ITest>) =>
 run().catch((err: Error) => console.log(err.stack));
 
 async function run() {
-  let res: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).exec();
+  const res: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).exec();
   console.log(res[0].name);
 
-  let res2: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]);
+  const res2: Array<ITest> = await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]);
   console.log(res2[0].name);
 
-  await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).cursor().exec().eachAsync(async (res) => {
+  await Test.aggregate<ITest>([{ $match: { name: 'foo' } }]).cursor().exec().eachAsync(async(res) => {
     console.log(res);
   });
-}
\ No newline at end of file
+}
diff --git a/test/typescript/base.ts b/test/typescript/base.ts
index e952d82f96c..a663ef05e1b 100644
--- a/test/typescript/base.ts
+++ b/test/typescript/base.ts
@@ -1,6 +1,6 @@
-import * as mongoose from 'mongoose'
+import * as mongoose from 'mongoose';
 
-Object.values(mongoose.models).forEach(model=>{
+Object.values(mongoose.models).forEach(model => {
   model.modelName;
-  model.findOne()
-});
\ No newline at end of file
+  model.findOne();
+});
diff --git a/test/typescript/collection.ts b/test/typescript/collection.ts
index 323bb08c719..12761e9968d 100644
--- a/test/typescript/collection.ts
+++ b/test/typescript/collection.ts
@@ -10,8 +10,8 @@ interface ITest extends Document {
 const Test = model<ITest>('Test', schema);
 
 Test.collection.collectionName;
-Test.collection.findOne({})
-Test.collection.findOneAndDelete({})
-Test.collection.ensureIndex()
-Test.collection.findAndModify()
-Test.collection.getIndexes()
\ No newline at end of file
+Test.collection.findOne({});
+Test.collection.findOneAndDelete({});
+Test.collection.ensureIndex();
+Test.collection.findAndModify();
+Test.collection.getIndexes();
diff --git a/test/typescript/connectSyntax.ts b/test/typescript/connectSyntax.ts
index 1b84311dd7e..414a747eec0 100644
--- a/test/typescript/connectSyntax.ts
+++ b/test/typescript/connectSyntax.ts
@@ -5,10 +5,10 @@ connect('mongodb://localhost:27017/test', {
   useNewUrlParser: true,
   useFindAndModify: true,
   useCreateIndex: true,
-  useUnifiedTopology: true,
+  useUnifiedTopology: true
 }).then(mongoose => console.log(mongoose.connect));
 
 // Callback
 connect('mongodb://localhost:27017/test', { useNewUrlParser: true, useUnifiedTopology: true }, (err: Error | null) => {
   console.log(err);
-});
\ No newline at end of file
+});
diff --git a/test/typescript/discriminator.ts b/test/typescript/discriminator.ts
index 30e43378107..9b80adae4b9 100644
--- a/test/typescript/discriminator.ts
+++ b/test/typescript/discriminator.ts
@@ -25,48 +25,48 @@ function test(): void {
     Enchantment = 'enchantment',
     Land = 'land',
   }
-  
+
   interface CardDb extends Document {
     _id: Types.ObjectId;
     type: CardType;
   }
-  
+
   interface LandDb extends CardDb {
     type: CardType.Land;
   }
-  
+
   const cardDbBaseSchemaDefinition: SchemaDefinition = {
-    type: { type: String, required: true },
+    type: { type: String, required: true }
   };
-  
+
   const cardDbSchemaOptions: SchemaOptions = { discriminatorKey: 'type' };
-  
+
   const cardDbSchema: Schema = new Schema(
     cardDbBaseSchemaDefinition,
     cardDbSchemaOptions,
   );
-  
+
   const cardDbModel: Model<CardDb> = mongoose.model<CardDb>(
     'Card',
     cardDbSchema,
     'card',
   );
-  
+
   const landDbAdditionalPropertiesSchemaDefinition: SchemaDefinition = {};
-  
+
   const landDbSchema: Schema = new Schema(
     landDbAdditionalPropertiesSchemaDefinition,
   );
-  
+
   const landDbModel: Model<LandDb> = cardDbModel.discriminator<LandDb>(
     'Land',
     landDbSchema,
     CardType.Land,
   );
-  
+
   const sampleLandDb: LandDb = new landDbModel({
-    type: CardType.Land,
+    type: CardType.Land
   });
-  
+
   const sampleCardDb: CardDb = sampleLandDb;
-}
\ No newline at end of file
+}
diff --git a/test/typescript/methods.ts b/test/typescript/methods.ts
index 7fe90a4755b..c39bf24243d 100644
--- a/test/typescript/methods.ts
+++ b/test/typescript/methods.ts
@@ -6,12 +6,12 @@ interface ITest extends Document {
 }
 
 const TestSchema = new Schema({
-  foo: { type: String, required: true },
+  foo: { type: String, required: true }
 });
 
 TestSchema.methods.getAnswer = function(): number {
   return 42;
-}
+};
 
 const Test = connection.model<ITest>('Test', TestSchema);
 
@@ -19,4 +19,4 @@ Test.create({ foo: 'test' });
 
 const doc: ITest = new Test({ foo: 'test' });
 
-Math.floor(doc.getAnswer());
\ No newline at end of file
+Math.floor(doc.getAnswer());
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index c39d1e068d5..5c941ea887a 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -30,8 +30,9 @@ schema.post<ITest>('save', function() {
   console.log(this.name);
 });
 
+// eslint-disable-next-line @typescript-eslint/ban-types
 schema.post<ITest>('save', function(err: Error, res: ITest, next: Function) {
   console.log(this.name, err.stack);
 });
 
-const Test = model<ITest>('Test', schema);
\ No newline at end of file
+const Test = model<ITest>('Test', schema);
diff --git a/test/typescript/modelInheritance.ts b/test/typescript/modelInheritance.ts
index 0a720836617..d31b4854f60 100644
--- a/test/typescript/modelInheritance.ts
+++ b/test/typescript/modelInheritance.ts
@@ -7,7 +7,7 @@ class InteractsWithDatabase extends Model {
 }
 
 class SourceProvider extends InteractsWithDatabase {
-  static async deleteInstallation (installationId: number): Promise<void> {
+  static async deleteInstallation(installationId: number): Promise<void> {
     await this.findOneAndDelete({ installationId });
   }
-}
\ No newline at end of file
+}
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 4b4bb75a63f..15a76f55d58 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -4,15 +4,15 @@ function conventionalSyntax(): void {
   interface ITest extends Document {
     foo: string;
   }
-  
+
   const TestSchema = new Schema({
-    foo: { type: String, required: true },
+    foo: { type: String, required: true }
   });
-  
+
   const Test = connection.model<ITest>('Test', TestSchema);
-  
+
   const bar = (SomeModel: Model<ITest>) => console.log(SomeModel);
-  
+
   bar(Test);
 }
 
@@ -21,9 +21,9 @@ function tAndDocSyntax(): void {
     id: number;
     foo: string;
   }
-  
+
   const TestSchema = new Schema({
-    foo: { type: String, required: true },
+    foo: { type: String, required: true }
   });
 
   const Test = connection.model<ITest & Document>('Test', TestSchema);
@@ -36,12 +36,12 @@ function tAndDocSyntax(): void {
 const ExpiresSchema = new Schema({
   ttl: {
     type: Date,
-    expires: 3600,
-  },
+    expires: 3600
+  }
 });
 
 interface IProject extends Document {
-  name: String;
+  name: string;
 }
 
 interface ProjectModel extends Model<IProject> {
@@ -52,4 +52,4 @@ const projectSchema: Schema = new Schema({ name: String });
 projectSchema.statics.myStatic = () => 42;
 
 const Project = connection.model<IProject, ProjectModel>('Project', projectSchema);
-Project.myStatic();
\ No newline at end of file
+Project.myStatic();
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index cf4fe4b6c95..1c935e46d13 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -36,6 +36,6 @@ Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITe
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { $set: { name: 'test2' } }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest | null) => console.log(res));
-Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true }).then((res: ITest) => { res.name = 'test4' });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true }).then((res: ITest) => { res.name = 'test4'; });
 
-Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
\ No newline at end of file
+Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
diff --git a/test/typescript/querycursor.ts b/test/typescript/querycursor.ts
index 2592bf98e68..6a03ee90c72 100644
--- a/test/typescript/querycursor.ts
+++ b/test/typescript/querycursor.ts
@@ -8,5 +8,5 @@ interface ITest extends Document {
 
 const Test = model<ITest>('Test', schema);
 
-Test.find().cursor().eachAsync(async (doc: ITest) => console.log(doc.name)).
-  then(() => console.log('Done!'));
\ No newline at end of file
+Test.find().cursor().eachAsync(async(doc: ITest) => console.log(doc.name)).
+  then(() => console.log('Done!'));
diff --git a/test/typescript/subdocuments.ts b/test/typescript/subdocuments.ts
index 19b132ad6af..a1b71f4e0aa 100644
--- a/test/typescript/subdocuments.ts
+++ b/test/typescript/subdocuments.ts
@@ -12,12 +12,12 @@ const schema: Schema = new Schema({
   docarr2: [{
     type: childSchema,
     _id: false
-  }],
+  }]
 });
 
 interface ITest extends Document {
-  child1: { name: String },
-  child2: { name: String }
+  child1: { name: string },
+  child2: { name: string }
 }
 
 const Test = model<ITest>('Test', schema);
@@ -25,4 +25,4 @@ const Test = model<ITest>('Test', schema);
 const doc: ITest = new Test({});
 
 doc.child1 = { name: 'test1' };
-doc.child2 = { name: 'test2' };
\ No newline at end of file
+doc.child2 = { name: 'test2' };

From 1bfed7860314950ca3702cf84d762cd18f0b407e Mon Sep 17 00:00:00 2001
From: simon <simon.tretter@hokify.com>
Date: Mon, 21 Dec 2020 10:32:07 +0100
Subject: [PATCH 1531/2348] lint: use const instead of var for ObjectId

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index b5e2af77a8d..06a97d9e9b8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1722,7 +1722,7 @@ declare module 'mongoose' {
       toObject(options?: ToObjectOptions & { flattenMaps?: boolean }): any;
     }
 
-    var ObjectId: ObjectIdConstructor;
+    const ObjectId: ObjectIdConstructor;
 
     class _ObjectId extends mongodb.ObjectID {
       _id?: ObjectId;

From ff98825956d651a80242a516ab5fc55a82706563 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Dec 2020 11:06:17 -0500
Subject: [PATCH 1532/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 2e7e954feb7..0249fbd1115 100644
--- a/index.pug
+++ b/index.pug
@@ -340,6 +340,9 @@ html(lang='en')
               <a rel="sponsored" href="https://followerspromotion.com/buy-instagram-likes/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/followerspromo.png" style="height: 100px" alt="Buy Instagram Likes">
               </a>
+              <a rel="sponsored" href="https://nflthursday.com/">
+                <img class="sponsor" src="https://images.opencollective.com/nfl-thursday/ac3e3cc/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 3de30e6e4bf3f6a42e3dcba30a79b1106e35f497 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 22 Dec 2020 20:36:36 -0500
Subject: [PATCH 1533/2348] chore: fix eslint version and disable
 no-explicit-any re #9729

---
 package.json | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/package.json b/package.json
index 084487f8c36..07cd4cbb099 100644
--- a/package.json
+++ b/package.json
@@ -48,7 +48,7 @@
     "cheerio": "1.0.0-rc.2",
     "co": "4.6.0",
     "dox": "0.3.1",
-    "eslint": "^7.1.0",
+    "eslint": "7.1.0",
     "eslint-plugin-mocha-no-only": "1.1.0",
     "highlight.js": "9.18.2",
     "lodash.isequal": "4.5.0",
@@ -117,9 +117,12 @@
         ],
         "plugins": [
           "@typescript-eslint"
-        ]
+        ],
+        "rules": {
+          "@typescript-eslint/no-explicit-any": "off"
+        }
       }
-      ],
+    ],
     "plugins": [
       "mocha-no-only"
     ],

From a68493386e7dbbf7443ffe359b0a5d5b631a36c3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Dec 2020 13:53:04 -0500
Subject: [PATCH 1534/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 0249fbd1115..6e8a83bded6 100644
--- a/index.pug
+++ b/index.pug
@@ -343,6 +343,9 @@ html(lang='en')
               <a rel="sponsored" href="https://nflthursday.com/">
                 <img class="sponsor" src="https://images.opencollective.com/nfl-thursday/ac3e3cc/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://njsportsjournal.com/">
+                <img class="sponsor" src="https://images.opencollective.com/njsj1/9bf603f/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 5e7ac07eb92b8fb89690f0f6bc11b70cc3ddfab7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Thu, 24 Dec 2020 19:57:26 +0200
Subject: [PATCH 1535/2348] fix(index.d.ts): deprecate Model.update(...)

---
 index.d.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 06a97d9e9b8..502fefe793f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -827,7 +827,10 @@ declare module 'mongoose' {
     /** Schema the model uses. */
     schema: Schema;
 
-    /** Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option. */
+    /**
+     * @deprecated use `updateOne` or `updateMany` instead.
+     * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
+     */
     update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */

From ab8c33b20adfbe79e5fa4b62c2777d9bf0c5b2fd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 24 Dec 2020 23:40:26 -0500
Subject: [PATCH 1536/2348] chore: fix tslint plugin versions

---
 package.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 07cd4cbb099..e1710743f5b 100644
--- a/package.json
+++ b/package.json
@@ -35,8 +35,8 @@
   "devDependencies": {
     "@babel/core": "7.10.5",
     "@babel/preset-env": "7.10.4",
-    "@typescript-eslint/eslint-plugin": "^4.10.0",
-    "@typescript-eslint/parser": "^4.10.0",
+    "@typescript-eslint/eslint-plugin": "4.10.0",
+    "@typescript-eslint/parser": "4.10.0",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",

From 3326dc737fb663c3592828e3057605c0d4ecad5d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 26 Dec 2020 13:31:56 -0500
Subject: [PATCH 1537/2348] chore: fix breaking changes in #9725

---
 index.d.ts                | 32 ++++++++++++++------------------
 test/typescript/models.ts |  4 ++--
 2 files changed, 16 insertions(+), 20 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4cf161b7ff1..783c0f28050 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,7 +99,7 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document>(name: string, schema?: Schema<T>, collection?: string, skipInit?: boolean): Model<T>;
+  export function model<T extends Document>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
   export function model<T extends Document, U extends Model<T>>(
     name: string,
     schema?: Schema<T, U>,
@@ -1033,7 +1033,7 @@ declare module 'mongoose' {
     useProjection?: boolean;
   }
 
-  class Schema<D extends Document = Document, M extends Model<D> = Model<D>> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1082,13 +1082,11 @@ declare module 'mongoose' {
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    method<F extends keyof D>(name: F, fn: D[F], opts?: any): this;
-    method(obj: { [F in keyof D]: D[F] }): this;
+    method(name: string, fn: Function, opts?: any): this;
+    method(obj: { [name: string]: Function }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: {
-      [F in keyof D]: D[F];
-    };
+    methods: { [name: string]: Function };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1109,21 +1107,21 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = D>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<Document> = M>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<DocType> = M>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = D>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<Document> = M>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<DocType> = M>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = D>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Document = DocType>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<Document> = M>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<DocType> = M>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: any;
@@ -1142,14 +1140,12 @@ declare module 'mongoose' {
 
     /** Adds static "class" methods to Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    static<F extends keyof M>(name: F, fn: M[F]): this;
+    static(name: string, fn: Function): this;
     // eslint-disable-next-line @typescript-eslint/ban-types
-    static (obj: { [F in keyof M]: M[F] }): this;
+    static(obj: { [name: string]: Function }): this;
 
     /** Object of currently defined statics on this schema. */
-    statics: {
-      [F in keyof M]: M[F];
-    };
+    statics: { [name: string]: Function };
 
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 840a3f0ee48..132240457a5 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -6,7 +6,7 @@ function conventionalSyntax(): void {
   }
 
   const TestSchema = new Schema<ITest>({
-    foo: { type: String, required: true };
+    foo: { type: String, required: true }
   });
 
   const Test = connection.model<ITest>('Test', TestSchema);
@@ -23,7 +23,7 @@ function tAndDocSyntax(): void {
   }
 
   const TestSchema = new Schema<ITest & Document>({
-    foo: { type: String, required: true };
+    foo: { type: String, required: true }
   });
 
   const Test = connection.model<ITest & Document>('Test', TestSchema);

From be55448751de9e7269c56ca314e3480f3e9507e1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 26 Dec 2020 13:37:26 -0500
Subject: [PATCH 1538/2348] style: fix lint

---
 index.d.ts                | 18 +++++++++---------
 package.json              |  3 ++-
 test/typescript/models.ts |  4 ++--
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 783c0f28050..c50b302ebca 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1107,21 +1107,21 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = DocType>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<DocType> = M>(method: "insertMany" | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = DocType>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
-    post<T extends Model<DocType> = M>(method: "insertMany" | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = DocType>(method: "validate" | "save" | "remove" | "updateOne" | "deleteOne" | "init" | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Aggregate<any> = Aggregate<any>>(method: "aggregate" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<DocType> = M>(method: "insertMany" | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: any;
diff --git a/package.json b/package.json
index e1710743f5b..5122220fb8f 100644
--- a/package.json
+++ b/package.json
@@ -119,7 +119,8 @@
           "@typescript-eslint"
         ],
         "rules": {
-          "@typescript-eslint/no-explicit-any": "off"
+          "@typescript-eslint/no-explicit-any": "off",
+          "@typescript-eslint/ban-types": "off"
         }
       }
     ],
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 132240457a5..e383c5818b7 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -51,11 +51,11 @@ interface ProjectModel extends Model<IProject> {
 
 const projectSchema = new Schema<IProject, ProjectModel>({ name: String });
 
-projectSchema.pre('save', function () {
+projectSchema.pre('save', function() {
   // this => IProject
 });
 
-projectSchema.post('save', function () {
+projectSchema.post('save', function() {
   // this => IProject
 });
 

From 8497929f582465f0ee75c88df20459b22ee06123 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 26 Dec 2020 19:01:31 -0500
Subject: [PATCH 1539/2348] fix(index.d.ts): allow passing generic parameter to
 overwrite `lean()` result type

Fix #9728
---
 index.d.ts                       | 2 +-
 test/typescript/leanDocuments.ts | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c50b302ebca..e10042c9a11 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1931,7 +1931,7 @@ declare module 'mongoose' {
     j(val: boolean | null): this;
 
     /** Sets the lean option. */
-    lean(val?: boolean | any): Query<LeanDocumentOrArray<ResultType>, DocType>;
+    lean<LeanResultType = LeanDocumentOrArray<ResultType>>(val?: boolean | any): Query<LeanResultType, DocType>;
 
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 38a818275ee..53e72a89bc0 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -6,9 +6,12 @@ class Subdoc extends Document {
   name: string;
 }
 
-interface ITest extends Document {
+interface ITestBase {
   name?: string;
   mixed?: any;
+}
+
+interface ITest extends ITestBase, Document {
   subdoc?: Subdoc;
   testMethod: () => number;
   id: string;
@@ -43,4 +46,6 @@ void async function main() {
 
   const _docs: LeanDocument<ITest>[] = await Test.find().lean();
   _docs[0].mixed = 42;
+
+  const _doc2: ITestBase = await Test.findOne().lean<ITestBase>();
 }();
\ No newline at end of file

From abc446abf9e8c74b07978ae9a8cf6923190e10b1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 26 Dec 2020 19:09:09 -0500
Subject: [PATCH 1540/2348] test: add test re: #9730

---
 test/typescript/models.ts | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index e383c5818b7..c65402c7829 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -33,6 +33,22 @@ function tAndDocSyntax(): void {
   const bar = (SomeModel: Model<ITest & Document>) => console.log(SomeModel);
 }
 
+function insertManyTest() {
+  interface ITest {
+    foo: string;
+  }
+
+  const TestSchema = new Schema<ITest & Document>({
+    foo: { type: String, required: true }
+  });
+
+  const Test = connection.model<ITest & Document>('Test', TestSchema);
+
+  Test.insertMany([{ foo: 'bar' }]).then(async res => {
+    res.length;
+  });
+}
+
 const ExpiresSchema = new Schema({
   ttl: {
     type: Date,

From b8aef4ec3c9493f902c5666b9dc97c4f55375e61 Mon Sep 17 00:00:00 2001
From: Sayan Saha <sayan@page2.page>
Date: Sun, 27 Dec 2020 22:58:34 +0530
Subject: [PATCH 1541/2348] fix(index.d.ts): add missing pre hook for
 findOneAndUpdate

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index e10042c9a11..da2919a5091 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1118,7 +1118,7 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'findOneAndUpdate' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;

From fd63d7029b1f88446a2729b323c043291880716b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Dec 2020 16:55:03 -0500
Subject: [PATCH 1542/2348] fix(document): apply `defaults` option to
 subdocument arrays

Fix #9736
---
 lib/types/embedded.js | 4 +++-
 test/document.test.js | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index c2d9f609900..c92d83493b2 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -29,9 +29,11 @@ const validatorErrorSymbol = require('../helpers/symbols').validatorErrorSymbol;
  */
 
 function EmbeddedDocument(obj, parentArr, skipId, fields, index) {
+  const options = {};
   if (parentArr != null && parentArr.isMongooseDocumentArray) {
     this.__parentArray = parentArr;
     this[documentArrayParent] = parentArr.$parent();
+    options.defaults = this[documentArrayParent].$__.$options.defaults;
   } else {
     this.__parentArray = undefined;
     this[documentArrayParent] = undefined;
@@ -39,7 +41,7 @@ function EmbeddedDocument(obj, parentArr, skipId, fields, index) {
   this.$setIndex(index);
   this.$isDocumentArrayElement = true;
 
-  Document.call(this, obj, fields, skipId);
+  Document.call(this, obj, fields, skipId, options);
 
   const _this = this;
   this.on('isNew', function(val) {
diff --git a/test/document.test.js b/test/document.test.js
index 7c84cf539b1..eeea3e59d14 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9122,7 +9122,7 @@ describe('document', function() {
       testNested: {
         prop: { type: String, default: 'bar' }
       },
-      testArray: [{ prop: { type: String, defualt: 'baz' } }],
+      testArray: [{ prop: { type: String, default: 'baz' } }],
       testSingleNested: new Schema({
         prop: { type: String, default: 'qux' }
       })

From 8a5776d59e70cb52f6b739cc80fef2895a567c93 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Dec 2020 17:02:12 -0500
Subject: [PATCH 1543/2348] chore: fix tests re: #9736

---
 lib/types/embedded.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index c92d83493b2..7f582727001 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -33,7 +33,6 @@ function EmbeddedDocument(obj, parentArr, skipId, fields, index) {
   if (parentArr != null && parentArr.isMongooseDocumentArray) {
     this.__parentArray = parentArr;
     this[documentArrayParent] = parentArr.$parent();
-    options.defaults = this[documentArrayParent].$__.$options.defaults;
   } else {
     this.__parentArray = undefined;
     this[documentArrayParent] = undefined;
@@ -41,6 +40,10 @@ function EmbeddedDocument(obj, parentArr, skipId, fields, index) {
   this.$setIndex(index);
   this.$isDocumentArrayElement = true;
 
+  if (this[documentArrayParent] != null) {
+    options.defaults = this[documentArrayParent].$__.$options.defaults;
+  }
+
   Document.call(this, obj, fields, skipId, options);
 
   const _this = this;

From 71b76fef27872a5dacaedf85823142827d14d296 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Dec 2020 18:02:01 -0500
Subject: [PATCH 1544/2348] test(document): repro #9651

---
 test/document.test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index eeea3e59d14..71b60fac595 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9814,4 +9814,24 @@ describe('document', function() {
 
     assert.strictEqual(testObject.get(''), void 0);
   });
+
+  it('keeps atomics when assigning array to filtered array (gh-9651)', function() {
+    const Model = db.model('Test', { arr: [{ abc: String }] });
+
+    return co(function*() {
+      const m1 = new Model({ arr: [{ abc: 'old' }] });
+      yield m1.save();
+
+      const m2 = yield Model.findOne({ _id: m1._id });
+
+      m2.arr = [];
+      m2.arr = m2.arr.filter(a => true);;
+      m2.arr.push({ abc: 'ghi' });
+      yield m2.save();
+
+      const fromDb = yield Model.findById(m1._id);
+      assert.equal(fromDb.arr.length, 1);
+      assert.equal(fromDb.arr[0].abc, 'ghi');
+    });
+  });
 });

From c16f8784d0a594440caae877a59c1ad196540b0b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 27 Dec 2020 18:22:59 -0500
Subject: [PATCH 1545/2348] fix(document): keeps atomics when assigning array
 to filtered array

Fix #9651
---
 lib/types/core_array.js | 16 +++++++++++++++-
 test/document.test.js   |  2 +-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index 15d90978f66..df66617d451 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -52,7 +52,7 @@ class CoreMongooseArray extends Array {
 
   $__getAtomics() {
     const ret = [];
-    const keys = Object.keys(this[arrayAtomicsSymbol]);
+    const keys = Object.keys(this[arrayAtomicsSymbol] || {});
     let i = keys.length;
 
     const opts = Object.assign({}, internalToObjectOptions, { _isNested: true });
@@ -843,10 +843,24 @@ class CoreMongooseArray extends Array {
     ret[arrayParentSymbol] = this[arrayParentSymbol];
     ret[arraySchemaSymbol] = this[arraySchemaSymbol];
     ret[arrayAtomicsSymbol] = this[arrayAtomicsSymbol];
+    ret[arrayPathSymbol] = this[arrayPathSymbol];
     ret[slicedSymbol] = true;
     return ret;
   }
 
+  /*!
+   * ignore
+   */
+
+  filter() {
+    const ret = super.filter.apply(this, arguments);
+    ret[arrayParentSymbol] = this[arrayParentSymbol];
+    ret[arraySchemaSymbol] = this[arraySchemaSymbol];
+    ret[arrayAtomicsSymbol] = this[arrayAtomicsSymbol];
+    ret[arrayPathSymbol] = this[arrayPathSymbol];
+    return ret;
+  }
+
   /*!
    * ignore
    */
diff --git a/test/document.test.js b/test/document.test.js
index 71b60fac595..6949d55d824 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9825,7 +9825,7 @@ describe('document', function() {
       const m2 = yield Model.findOne({ _id: m1._id });
 
       m2.arr = [];
-      m2.arr = m2.arr.filter(a => true);;
+      m2.arr = m2.arr.filter(() => true);
       m2.arr.push({ abc: 'ghi' });
       yield m2.save();
 

From 39591192ccf4a116d28f3ed4785f3e4b319ebe0c Mon Sep 17 00:00:00 2001
From: Sayan Saha <sayan@page2.page>
Date: Mon, 28 Dec 2020 12:09:23 +0530
Subject: [PATCH 1546/2348] fix(index.d.ts): add missing overloaded function
 for Document#populate()

---
 index.d.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/index.d.ts b/index.d.ts
index da2919a5091..6110544d9cc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -539,6 +539,7 @@ declare module 'mongoose' {
      * [`execPopulate()`](#document_Document-execPopulate).
      */
     populate(path: string, callback?: (err: CallbackError, res: this) => void): this;
+    populate(path: string, names: string, callback?: (err: any, res: this) => void): this;
     populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: (err: CallbackError, res: this) => void): this;
 
     /** Gets _id(s) used during population of the given `path`. If the path was not populated, returns `undefined`. */

From 978019559fdf2bc840f2aad65011c488df7dcd29 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 28 Dec 2020 15:37:07 -0500
Subject: [PATCH 1547/2348] fix: make fix for #9651 compatible with Node.js 4.x
 and 5.x

---
 lib/types/documentarray.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 2855ae4ff15..67afcbcfd3c 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -380,8 +380,7 @@ function MongooseDocumentArray(values, path, doc) {
   arr[arrayAtomicsSymbol] = {};
   arr[arraySchemaSymbol] = void 0;
   if (Array.isArray(values)) {
-    if (values instanceof CoreDocumentArray &&
-        values[arrayPathSymbol] === path &&
+    if (values[arrayPathSymbol] === path &&
         values[arrayParentSymbol] === doc) {
       arr[arrayAtomicsSymbol] = Object.assign({}, values[arrayAtomicsSymbol]);
     }

From 21f1f180e3ae23df28275e30e2522db913d553f2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 28 Dec 2020 15:47:51 -0500
Subject: [PATCH 1548/2348] chore: release 5.11.9

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f3cbda38d8f..087bb709e6f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.11.9 / 2020-12-28
+===================
+ * fix(document): keeps atomics when assigning array to filtered array #9651
+ * fix(document): apply `defaults` option to subdocument arrays #9736
+ * fix(index.d.ts): allow passing generic parameter to overwrite `lean()` result type #9728
+ * fix(index.d.ts): add missing pre hook for findOneAndUpdate #9743 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): schema methods & statics types #9725
+ * fix(index.d.ts): allow `id` paths with non-string values in TypeScript #9723
+ * fix(index.d.ts): support calling `createIndexes()` and `ensureIndexes()` with just callback #9706
+ * fix(index.d.ts): include `__v` in LeanDocuments #9687
+ * fix(index.d.ts): add missing `Aggregate#append()` #9714
+ * chore: add eslint typescript support and lint index.d.ts file #9729 [simllll](https://github.com/simllll)
+ * chore: add Github Actions #9688 [YC](https://github.com/YC)
+
 5.11.8 / 2020-12-14
 ===================
  * fix(index.d.ts): add missing single document populate #9696 [YC](https://github.com/YC)
diff --git a/package.json b/package.json
index 5122220fb8f..6328ed80b14 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.8",
+  "version": "5.11.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From eb2f29e59e5af508986e7c0ca573162e3e5dcb69 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 29 Dec 2020 17:26:17 -0500
Subject: [PATCH 1549/2348] fix(document): make fix for #9396 handle null
 values more gracefully

Fix #9709
---
 lib/document.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 5e9a541460b..b127476a24a 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1041,11 +1041,12 @@ Document.prototype.$set = function $set(path, val, type, options) {
     if (typeof val === 'object' && val != null) {
       const hasPriorVal = this.$__.savedState != null && this.$__.savedState.hasOwnProperty(path);
       if (this.$__.savedState != null && !this.isNew && !this.$__.savedState.hasOwnProperty(path)) {
-        this.$__.savedState[path] = this.$__getValue(path);
+        const priorVal = this.$__getValue(path);
+        this.$__.savedState[path] = priorVal;
 
-        const keys = Object.keys(this.$__.savedState[path]);
+        const keys = Object.keys(priorVal || {});
         for (const key of keys) {
-          this.$__.savedState[path + '.' + key] = this.$__.savedState[path][key];
+          this.$__.savedState[path + '.' + key] = priorVal[key];
         }
       }
 

From 93b5ef826beb0b5bad8b1d3ccb3d87503c59785e Mon Sep 17 00:00:00 2001
From: Sangwoo Park <eicpein@gmail.com>
Date: Wed, 30 Dec 2020 12:38:07 +0900
Subject: [PATCH 1550/2348] fix(index.d.ts): add missing function for
 Aggregate#group()

---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 6110544d9cc..b6775d5ad24 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2271,6 +2271,9 @@ declare module 'mongoose' {
 
     /** Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection. */
     graphLookup(options: any): this;
+                                          
+    /** Appends new custom $group operator to this aggregate pipeline. */
+    group(arg: any): this;
 
     /** Sets the hint option for the aggregation query (ignored for < 3.6.0) */
     hint(value: Record<string, unknown> | string): this;

From fca05293a7ccb810a0fa835b3a57996d31e88158 Mon Sep 17 00:00:00 2001
From: hasezoey <hasezoey@gmail.com>
Date: Wed, 30 Dec 2020 16:02:22 +0100
Subject: [PATCH 1551/2348] fix(index.d.ts): allow Model.create param1
 overwrite

---
 index.d.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b6775d5ad24..e84880e2eab 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -630,11 +630,11 @@ declare module 'mongoose' {
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
 
     /** Creates a new document or documents */
-    create(doc: T | DocumentDefinition<T>): Promise<T>;
-    create(docs: Array<T | DocumentDefinition<T>>, options?: SaveOptions): Promise<Array<T>>;
-    create(...docs: Array<T | DocumentDefinition<T>>): Promise<T>;
-    create(doc: T | DocumentDefinition<T>, callback: (err: CallbackError, doc: T) => void): void;
-    create(docs: Array<T | DocumentDefinition<T>>, callback: (err: CallbackError, docs: Array<T>) => void): void;
+    create<Z = T | DocumentDefinition<T>>(doc: Z): Promise<T>;
+    create<Z = T | DocumentDefinition<T>>(docs: Array<Z>, options?: SaveOptions): Promise<Array<T>>;
+    create<Z = T | DocumentDefinition<T>>(...docs: Array<Z>): Promise<T>;
+    create<Z = T | DocumentDefinition<T>>(doc: Z, callback: (err: CallbackError, doc: T) => void): void;
+    create<Z = T | DocumentDefinition<T>>(docs: Array<Z>, callback: (err: CallbackError, docs: Array<T>) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,

From 883b0f8e2aaf7e2c12d68d3b93a6cefcc007ff13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Dec 2020 10:44:00 -0500
Subject: [PATCH 1552/2348] fix: upgrade mpath to 0.8.2 avoid issue from #9640

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 6328ed80b14..cec504add3b 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "kareem": "2.3.2",
     "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
-    "mpath": "0.8.1",
+    "mpath": "0.8.2",
     "mquery": "3.2.3",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",

From 811db7c6961ef0a8d21695cae3ad280de16440fa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Dec 2020 11:09:48 -0500
Subject: [PATCH 1553/2348] fix: upgrade mpath -> 0.8.3 for Node.js 4
 compatible fix to #9640

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index cec504add3b..e52fbbd9838 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "kareem": "2.3.2",
     "mongodb": "3.6.3",
     "mongoose-legacy-pluralize": "1.0.2",
-    "mpath": "0.8.2",
+    "mpath": "0.8.3",
     "mquery": "3.2.3",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",

From 4cf10b1fd9e2ee30300ee63b8791ecf1541d207e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Dec 2020 11:13:45 -0500
Subject: [PATCH 1554/2348] style: fix lint

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index b6775d5ad24..83f00c34125 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2271,7 +2271,7 @@ declare module 'mongoose' {
 
     /** Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection. */
     graphLookup(options: any): this;
-                                          
+
     /** Appends new custom $group operator to this aggregate pipeline. */
     group(arg: any): this;
 

From 495e1978d414f04b40667d00036d2f92d6bd7bd1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Dec 2020 11:42:46 -0500
Subject: [PATCH 1555/2348] fix(index.d.ts): allow `null` as an enum value for
 schematypes

Fix #9746
---
 index.d.ts                   |  2 +-
 test/typescript/main.test.js |  8 ++++++++
 test/typescript/schema.ts    | 10 ++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/schema.ts

diff --git a/index.d.ts b/index.d.ts
index fd9a81c9dbb..2422af15181 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1407,7 +1407,7 @@ declare module 'mongoose' {
     set?: (value: T, schematype?: this) => any;
 
     /** array of allowed values for this path. Allowed for strings, numbers, and arrays of strings */
-    enum?: Array<string | number>
+    enum?: Array<string | number | null>
 
     /** The default [subtype](http://bsonspec.org/spec.html) associated with this buffer when it is stored in MongoDB. Only allowed for buffer paths */
     subtype?: number
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 38b1f76f3eb..70e9d8ae3c0 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -172,6 +172,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('schema', function() {
+    const errors = runTest('schema.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file, configOverride) {
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
new file mode 100644
index 00000000000..85d35a4b94e
--- /dev/null
+++ b/test/typescript/schema.ts
@@ -0,0 +1,10 @@
+import { Schema } from 'mongoose';
+
+const schema: Schema = new Schema({
+  name: String,
+  enumWithNull: {
+    type: String,
+    enum: ['Test', null],
+    default: null
+  }
+});

From 685ca90311c12be9f49b2c92bd0d47338270dc42 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 31 Dec 2020 09:07:00 -0500
Subject: [PATCH 1556/2348] docs(guide+schema): make schema API docs and guide
 docs' list of Schema options line up

Fix #9749
---
 docs/guide.pug | 1 +
 lib/schema.js  | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/docs/guide.pug b/docs/guide.pug
index 819080193fe..1695fb55869 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -436,6 +436,7 @@ block content
     - [toJSON](#toJSON)
     - [toObject](#toObject)
     - [typeKey](#typeKey)
+    - [typePojoToMixed](/docs/schematypes.html#mixed)
     - [useNestedStrict](#useNestedStrict)
     - [validateBeforeSave](#validateBeforeSave)
     - [versionKey](#versionKey)
diff --git a/lib/schema.js b/lib/schema.js
index 1dd9d9e704c..4483edcf120 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -50,6 +50,7 @@ let id = 0;
  * - [autoIndex](/docs/guide.html#autoIndex): bool - defaults to null (which means use the connection's autoIndex option)
  * - [autoCreate](/docs/guide.html#autoCreate): bool - defaults to null (which means use the connection's autoCreate option)
  * - [bufferCommands](/docs/guide.html#bufferCommands): bool - defaults to true
+ * - [bufferTimeoutMS](/docs/guide.html#bufferTimeoutMS): number - defaults to 10000 (10 seconds). If `bufferCommands` is enabled, the amount of time Mongoose will wait for connectivity to be restablished before erroring out.
  * - [capped](/docs/guide.html#capped): bool - defaults to false
  * - [collection](/docs/guide.html#collection): string - no default
  * - [id](/docs/guide.html#id): bool - defaults to true
@@ -67,6 +68,7 @@ let id = 0;
  * - [useNestedStrict](/docs/guide.html#useNestedStrict) - boolean - defaults to false
  * - [validateBeforeSave](/docs/guide.html#validateBeforeSave) - bool - defaults to `true`
  * - [versionKey](/docs/guide.html#versionKey): string or object - defaults to "__v"
+ * - [optimisticConcurrency](/docs/guide.html#optimisticConcurrency): bool - defaults to false. Set to true to enable [optimistic concurrency](https://thecodebarbarian.com/whats-new-in-mongoose-5-10-optimistic-concurrency.html).
  * - [collation](/docs/guide.html#collation): object - defaults to null (which means use no collation)
  * - [selectPopulatedPaths](/docs/guide.html#selectPopulatedPaths): boolean - defaults to `true`
  * - [skipVersioning](/docs/guide.html#skipVersioning): object - paths to exclude from versioning

From 730f889d1cb4ba93a310bb98b556078c40ce3cae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 31 Dec 2020 09:14:21 -0500
Subject: [PATCH 1557/2348] fix(index.d.ts): improve autocomplete for query
 middleware

Fix #9752
Re: #9743
---
 index.d.ts | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 2422af15181..ee297da9b72 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1034,6 +1034,8 @@ declare module 'mongoose' {
     useProjection?: boolean;
   }
 
+  type MongooseQueryMiddleware = 'count' | 'deleteMany' | 'deleteOne' | 'find' | 'findOne' | 'findOneAndDelete' | 'findOneAndRemove' | 'findOneAndUpdate' | 'remove' | 'update' | 'updateOne' | 'updateMany';
+
   class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>> extends events.EventEmitter {
     /**
      * Create a new schema
@@ -1109,18 +1111,18 @@ declare module 'mongoose' {
 
     /** Defines a post hook for the model. */
     post<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
     post<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'findOneAndUpdate' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
-    pre<T extends Query<any, any> = Query<any, any>>(method: string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 

From 639e4ffd7d3712952a5f60b2c2f6522f7bd49830 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 1 Jan 2021 20:34:50 -0500
Subject: [PATCH 1558/2348] fix(model): support `populate` option for
 `insertMany()` as a workaround for mongoose-autopopulate

Re: #9720
---
 lib/model.js       | 12 ++++++++++++
 test/model.test.js | 29 +++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index 4b2e514ccfd..3e7035eab91 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3359,6 +3359,18 @@ Model.$__insertMany = function(arr, options, callback) {
         }
         return callback(null, res);
       }
+
+      if (options.populate != null) {
+        return _this.populate(docAttributes, options.populate, err => {
+          if (err != null) {
+            error.insertedDocs = docAttributes;
+            return callback(err);
+          }
+
+          callback(null, docs);
+        });
+      }
+
       callback(null, docAttributes);
     });
   });
diff --git a/test/model.test.js b/test/model.test.js
index 5e0fc54d1f5..59bfc680911 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4726,6 +4726,35 @@ describe('Model', function() {
       });
     });
 
+    it('insertMany() populate option (gh-9720)', function() {
+      const schema = new Schema({
+        name: { type: String, required: true }
+      });
+      const Movie = db.model('Movie', schema);
+      const Person = db.model('Person', Schema({
+        name: String,
+        favoriteMovie: {
+          type: 'ObjectId',
+          ref: 'Movie'
+        }
+      }));
+
+      return co(function*() {
+        const movies = yield Movie.create([
+          { name: 'The Empire Strikes Back' },
+          { name: 'Jingle All The Way' }
+        ]);
+        const people = yield Person.insertMany([
+          { name: 'Test1', favoriteMovie: movies[1]._id },
+          { name: 'Test2', favoriteMovie: movies[0]._id }
+        ], { populate: 'favoriteMovie' });
+
+        assert.equal(people.length, 2);
+        assert.equal(people[0].favoriteMovie.name, 'Jingle All The Way');
+        assert.equal(people[1].favoriteMovie.name, 'The Empire Strikes Back');
+      });
+    });
+
     it('insertMany() sets `isNew` for inserted documents with `ordered = false` (gh-9677)', function() {
       const schema = new Schema({
         title: { type: String, required: true, unique: true }

From 733e4f64def2f301455dca2b91255f59e15f0a74 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 1 Jan 2021 20:38:57 -0500
Subject: [PATCH 1559/2348] docs: add `populate` to list of insertMany options
 re: #9720

---
 index.d.ts   | 1 +
 lib/model.js | 1 +
 2 files changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index ee297da9b72..dd86ac89657 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -933,6 +933,7 @@ declare module 'mongoose' {
     ordered?: boolean;
     lean?: boolean;
     session?: mongodb.ClientSession;
+    populate?: string | string[] | PopulateOptions | PopulateOptions[];
   }
 
   interface InsertManyResult extends mongodb.InsertWriteOpResult<any> {
diff --git a/lib/model.js b/lib/model.js
index 3e7035eab91..cec00dc480f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3212,6 +3212,7 @@ Model.startSession = function() {
  * @param {Boolean} [options.rawResult = false] if false, the returned promise resolves to the documents that passed mongoose document validation. If `true`, will return the [raw result from the MongoDB driver](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~insertWriteOpCallback) with a `mongoose` property that contains `validationErrors` if this is an unordered `insertMany`.
  * @param {Boolean} [options.lean = false] if `true`, skips hydrating and validating the documents. This option is useful if you need the extra performance, but Mongoose won't validate the documents before inserting.
  * @param {Number} [options.limit = null] this limits the number of documents being processed (validation/casting) by mongoose in parallel, this does **NOT** send the documents in batches to MongoDB. Use this option if you're processing a large number of documents and your app is running out of memory.
+ * @param {String|Object|Array} [options.populate = null] populates the result documents. This option is a no-op if `rawResult` is set.
  * @param {Function} [callback] callback
  * @return {Promise} resolving to the raw result from the MongoDB driver if `options.rawResult` was `true`, or the documents that passed validation, otherwise
  * @api public

From 6bf3750f81a00efedb0a52beb396b9dd335e5841 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 1 Jan 2021 21:11:42 -0500
Subject: [PATCH 1560/2348] fix(queryhelpers): avoid modifying `lean.virtuals`
 in place

Fix #9754
Fix vkarpov15/mongoose-lean-virtuals#48
---
 lib/queryhelpers.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index ae274e06092..26c2386b7fc 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -284,6 +284,7 @@ function makeLean(val) {
     option.options || (option.options = {});
 
     if (val != null && Array.isArray(val.virtuals)) {
+      val = Object.assign({}, val);
       val.virtuals = val.virtuals.
         filter(path => typeof path === 'string' && path.startsWith(option.path + '.')).
         map(path => path.slice(option.path.length + 1));

From 89625b1a028049f9ae82fe255e518c8600bac147 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 1 Jan 2021 21:59:08 -0500
Subject: [PATCH 1561/2348] docs(documents): add some more details about what
 the `save()` promise resolves to

Fix #9689
---
 docs/documents.pug | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/docs/documents.pug b/docs/documents.pug
index 12526491939..5ac1d1f7965 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -29,7 +29,8 @@ block content
     <ul class="toc">
       <li><a href="#documents-vs-models">Documents vs Models</a></li>
       <li><a href="#retrieving">Retrieving</a></li>
-      <li><a href="#updating">Updating</a></li>
+      <li><a href="#updating-using-save">Updating Using `save()`</a></li>
+      <li><a href="#updating-using-queries">Updating Using Queries</a></li>
       <li><a href="#validating">Validating</a></li>
       <li><a href="#overwriting">Overwriting</a></li>
     </ul>
@@ -67,7 +68,7 @@ block content
     doc instanceof mongoose.Document; // true
     ```
 
-    ### Updating
+    ### Updating Using `save()`
 
     Mongoose documents track changes. You can modify a document using vanilla
     JavaScript assignments and Mongoose will convert it into [MongoDB update operators](https://docs.mongodb.com/manual/reference/operator/update/).
@@ -80,6 +81,15 @@ block content
     await doc.save();
     ```
 
+    The `save()` method returns a promise. If `save()` succeeds, the promise
+    resolves to the document that was saved.
+
+    ```javascript
+    doc.save().then(savedDoc => {
+      savedDoc === doc; // true
+    });
+    ```
+
     If the document with the corresponding `_id` is not found, Mongoose will
     report a `DocumentNotFoundError`:
 
@@ -93,6 +103,8 @@ block content
     await doc.save(); // Throws DocumentNotFoundError
     ```
 
+    ### Updating Using Queries
+
     The [`save()`](api.html#model_Model-save) function is generally the right
     way to update a document with Mongoose. With `save()`, you get full
     [validation](validation.html) and [middleware](middleware.html).

From 82c84e8af5db8b908d203b5f6de9b22a5a1c87bf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 Jan 2021 09:42:19 -0500
Subject: [PATCH 1562/2348] perf(array): avoid unnecessary `path()` calls when
 creating nested arrays

Re: #9588
---
 lib/schema/array.js | 4 ++--
 lib/types/array.js  | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index d99280b409d..b6a6c85bafa 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -340,11 +340,11 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     }
 
     if (!(value && value.isMongooseArray)) {
-      value = MongooseArray(value, this._arrayPath || this.path, doc);
+      value = MongooseArray(value, this._arrayPath || this.path, doc, this);
     } else if (value && value.isMongooseArray) {
       // We need to create a new array, otherwise change tracking will
       // update the old doc (gh-4449)
-      value = MongooseArray(value, this._arrayPath || this.path, doc);
+      value = MongooseArray(value, this._arrayPath || this.path, doc, this);
     }
 
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
diff --git a/lib/types/array.js b/lib/types/array.js
index 41c51e5075b..65c5b8d58da 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -29,7 +29,7 @@ const _basePush = Array.prototype.push;
  * @see http://bit.ly/f6CnZU
  */
 
-function MongooseArray(values, path, doc) {
+function MongooseArray(values, path, doc, schematype) {
   // TODO: replace this with `new CoreMongooseArray().concat()` when we remove
   // support for node 4.x and 5.x, see https://i.imgur.com/UAAHk4S.png
   const arr = new CoreMongooseArray();
@@ -53,7 +53,7 @@ function MongooseArray(values, path, doc) {
   // to make more proof against unusual node environments
   if (doc && doc instanceof Document) {
     arr[arrayParentSymbol] = doc;
-    arr[arraySchemaSymbol] = doc.schema.path(path);
+    arr[arraySchemaSymbol] = schematype || doc.schema.path(path);
   }
 
   return arr;

From 3e318ad621185b219f860c43782f504b51566829 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 Jan 2021 10:42:46 -0500
Subject: [PATCH 1563/2348] perf(schema): avoid expensive `String#slice()` call
 when creating a new array

Re: #9588
---
 lib/schema.js       | 2 ++
 lib/schema/array.js | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 4483edcf120..af350ffbaa9 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -747,9 +747,11 @@ Schema.prototype.path = function(path, obj) {
       // Skip arrays of document arrays
       if (_schemaType.$isMongooseDocumentArray) {
         _schemaType.$embeddedSchemaType._arrayPath = arrayPath;
+        _schemaType.$embeddedSchemaType._arrayParentPath = path;
         _schemaType = _schemaType.$embeddedSchemaType.clone();
       } else {
         _schemaType.caster._arrayPath = arrayPath;
+        _schemaType.caster._arrayParentPath = path;
         _schemaType = _schemaType.caster.clone();
       }
 
diff --git a/lib/schema/array.js b/lib/schema/array.js
index b6a6c85bafa..47cd5aeb11d 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -364,8 +364,8 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
           const opts = {};
           if (options != null && options.arrayPath != null) {
             opts.arrayPath = options.arrayPath + '.' + i;
-          } else if (this.caster._arrayPath != null) {
-            opts.arrayPath = this.caster._arrayPath.slice(0, -2) + '.' + i;
+          } else if (this.caster._arrayParentPath != null) {
+            opts.arrayPath = this.caster._arrayParentPath + '.' + i;
           }
           value[i] = this.caster.cast(value[i], doc, init, void 0, opts);
         }

From 9cdc4315ce38288ae68d8b83fcb278b172ea5ec0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 Jan 2021 11:39:45 -0500
Subject: [PATCH 1564/2348] perf(schema): avoid setting `arrayPath` when
 casting to a non-array, avoid unnecessarily setting atomics

Re: #9588
---
 lib/schema/array.js | 23 +++++++++++++++--------
 lib/types/array.js  |  4 +++-
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 47cd5aeb11d..2609ba88f1a 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -352,22 +352,29 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
       return value;
     }
 
-    if (this.caster && this.casterConstructor !== Mixed) {
+    const caster = this.caster;
+    if (caster && this.casterConstructor !== Mixed) {
       try {
-        for (i = 0, l = value.length; i < l; i++) {
+        const len = value.length;
+        for (i = 0; i < len; i++) {
           // Special case: number arrays disallow undefined.
           // Re: gh-840
           // See commit 1298fe92d2c790a90594bd08199e45a4a09162a6
-          if (this.caster.instance === 'Number' && value[i] === void 0) {
+          if (caster.instance === 'Number' && value[i] === void 0) {
             throw new MongooseError('Mongoose number arrays disallow storing undefined');
           }
           const opts = {};
-          if (options != null && options.arrayPath != null) {
-            opts.arrayPath = options.arrayPath + '.' + i;
-          } else if (this.caster._arrayParentPath != null) {
-            opts.arrayPath = this.caster._arrayParentPath + '.' + i;
+          // Perf: creating `arrayPath` is expensive for large arrays.
+          // We only need `arrayPath` if this is a nested array, so
+          // skip if possible.
+          if (caster.$isMongooseArray) {
+            if (options != null && options.arrayPath != null) {
+              opts.arrayPath = options.arrayPath + '.' + i;
+            } else if (this.caster._arrayParentPath != null) {
+              opts.arrayPath = this.caster._arrayParentPath + '.' + i;
+            }
           }
-          value[i] = this.caster.cast(value[i], doc, init, void 0, opts);
+          value[i] = caster.cast(value[i], doc, init, void 0, opts);
         }
       } catch (e) {
         // rethrow
diff --git a/lib/types/array.js b/lib/types/array.js
index 65c5b8d58da..c5c093812fc 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -41,7 +41,9 @@ function MongooseArray(values, path, doc, schematype) {
       _basePush.call(arr, values[i]);
     }
 
-    arr[arrayAtomicsSymbol] = values[arrayAtomicsSymbol] || {};
+    if (values[arrayAtomicsSymbol] != null) {
+      arr[arrayAtomicsSymbol] = values[arrayAtomicsSymbol];
+    }
   }
 
   arr[arrayPathSymbol] = path;

From 1f3b4b1713522f9de628432f5c2763d54485a52b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 Jan 2021 13:40:04 -0500
Subject: [PATCH 1565/2348] perf(schema): avoid creating extra array when
 initializing array of arrays

Re: #9588
---
 lib/schema/array.js | 4 ++--
 lib/schematype.js   | 3 +--
 lib/types/array.js  | 2 --
 test/schema.test.js | 2 +-
 4 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 2609ba88f1a..7351cbef241 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -374,11 +374,11 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
               opts.arrayPath = this.caster._arrayParentPath + '.' + i;
             }
           }
-          value[i] = caster.cast(value[i], doc, init, void 0, opts);
+          value[i] = caster.applySetters(value[i], doc, init, void 0, opts);
         }
       } catch (e) {
         // rethrow
-        throw new CastError('[' + e.kind + ']', util.inspect(value), this.path, e, this);
+        throw new CastError('[' + e.kind + ']', util.inspect(value), this.path + '.' + i, e, this);
       }
     }
 
diff --git a/lib/schematype.js b/lib/schematype.js
index 3cd297c46f2..f54fbd9d92b 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1060,7 +1060,7 @@ SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
     v = setter.call(scope, v, this);
   }
 
-  if (Array.isArray(v) && caster && caster.setters) {
+  if (caster && !caster.$isMongooseArray && Array.isArray(v) && caster.setters) {
     const newVal = [];
 
     for (let i = 0; i < v.length; ++i) {
@@ -1078,7 +1078,6 @@ SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
     v = newVal;
   }
 
-
   return v;
 };
 
diff --git a/lib/types/array.js b/lib/types/array.js
index c5c093812fc..802a62887a1 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -30,8 +30,6 @@ const _basePush = Array.prototype.push;
  */
 
 function MongooseArray(values, path, doc, schematype) {
-  // TODO: replace this with `new CoreMongooseArray().concat()` when we remove
-  // support for node 4.x and 5.x, see https://i.imgur.com/UAAHk4S.png
   const arr = new CoreMongooseArray();
   arr[arrayAtomicsSymbol] = {};
 
diff --git a/test/schema.test.js b/test/schema.test.js
index 9f3557db1e7..3c688226e56 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -441,7 +441,7 @@ describe('schema', function() {
         threw = true;
         assert.equal(error.name, 'CastError');
         assert.equal(error.message,
-          'Cast to [[Number]] failed for value "[["abcd"]]" at path "nums"');
+          'Cast to [Number] failed for value "[["abcd"]]" at path "nums.0"');
       }
       assert.ok(threw);
 

From 04dd2be13dee1311c121ba1a099a773de6a1df49 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 2 Jan 2021 18:31:14 -0500
Subject: [PATCH 1566/2348] docs(subdocs): add section about subdocument
 defaults

Fix #7291
---
 docs/subdocs.pug | 61 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/docs/subdocs.pug b/docs/subdocs.pug
index 75400f2b6c3..25eac08bac4 100644
--- a/docs/subdocs.pug
+++ b/docs/subdocs.pug
@@ -45,6 +45,7 @@ block content
     <ul class="toc">
       <li><a href="#what-is-a-subdocument-">What is a Subdocument?</a></li>
       <li><a href="#subdocuments-versus-nested-paths">Subdocuments versus Nested Paths</a></li>
+      <li><a href="#subdocument-defaults">Subdocument Defaults</a></li>
       <li><a href="#finding-a-subdocument">Finding a Subdocument</a></li>
       <li><a href="#adding-subdocs-to-arrays">Adding Subdocs to Arrays</a></li>
       <li><a href="#removing-subdocs">Removing Subdocs</a></li>
@@ -178,6 +179,66 @@ block content
     doc2.child; // { name: Luke, age: 21 }
     ```
 
+    ### Subdocument Defaults
+
+    Subdocument paths are undefined by default, and Mongoose does
+    not apply subdocument defaults unless you set the subdocument
+    path to a non-nullish value.
+
+    ```javascript
+    const subdocumentSchema = new mongoose.Schema({
+      child: new mongoose.Schema({
+        name: String,
+        age: {
+          type: Number,
+          default: 0
+        }
+      })
+    });
+    const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
+
+    // Note that the `age` default has no effect, because `child`
+    // is `undefined`.
+    const doc = new Subdoc();
+    doc.child; // undefined
+    ```
+
+    However, if you set `doc.child` to any object, Mongoose will apply
+    the `age` default if necessary.
+
+    ```javascript
+    doc.child = {};
+    // Mongoose applies the `age` default:
+    doc.child.age; // 0
+    ```
+
+    Mongoose applies defaults recursively, which means there's a nice
+    workaround if you want to make sure Mongoose applies subdocument
+    defaults: make the subdocument path default to an empty object.
+
+    ```javascript
+    const childSchema = new mongoose.Schema({
+      name: String,
+      age: {
+        type: Number,
+        default: 0
+      }
+    });
+    const subdocumentSchema = new mongoose.Schema({
+      child: {
+        type: childSchema,
+        default: () => ({})
+      }
+    });
+    const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
+
+    // Note that Mongoose sets `age` to its default value 0, because
+    // `child` defaults to an empty object and Mongoose applies
+    // defaults to that empty object.
+    const doc = new Subdoc();
+    doc.child; // { age: 0 }
+    ```
+
   h3#finding-a-subdocument Finding a Subdocument
   :markdown
     Each subdocument has an `_id` by default. Mongoose document arrays have a

From 6497b47e0e0d9bd8211be22fbd3dd3299f817a94 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Mon, 4 Jan 2021 21:02:32 +1100
Subject: [PATCH 1567/2348] ci(fix): run on PR and update badge

---
 .github/workflows/test.yml | 4 +++-
 README.md                  | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 208e3ca1caa..96519ae8a18 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -1,5 +1,7 @@
 name: Test
-on: push
+on:
+    pull_request:
+    push:
 jobs:
   test:
     runs-on: ubuntu-18.04
diff --git a/README.md b/README.md
index 0da1d48835c..b28bed66538 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 Mongoose is a [MongoDB](https://www.mongodb.org/) object modeling tool designed to work in an asynchronous environment. Mongoose supports both promises and callbacks.
 
 [![Slack Status](http://slack.mongoosejs.io/badge.svg)](http://slack.mongoosejs.io)
-[![Build Status](https://api.travis-ci.org/Automattic/mongoose.svg?branch=master)](https://travis-ci.org/Automattic/mongoose)
+[![Build Status](https://github.com/Automattic/mongoose/workflows/Test/badge.svg)](https://github.com/Automattic/mongoose)
 [![NPM version](https://badge.fury.io/js/mongoose.svg)](http://badge.fury.io/js/mongoose)
 
 [![npm](https://nodei.co/npm/mongoose.png)](https://www.npmjs.com/package/mongoose)

From 929784f337444298ecb7ba8f6e9e11fcd6ae8de2 Mon Sep 17 00:00:00 2001
From: Reza <m.roohian87@gmail.com>
Date: Mon, 4 Jan 2021 13:07:14 +0100
Subject: [PATCH 1568/2348] Make SchemaDefinition accept a model

Make SchemaDefinition accept a model for more stricter type checking and making the schema consistent with typescript models.
---
 index.d.ts | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index dd86ac89657..4b740698f90 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1161,10 +1161,11 @@ declare module 'mongoose' {
     virtualpath(name: string): VirtualType | null;
   }
 
-  interface SchemaDefinition {
-    // eslint-disable-next-line @typescript-eslint/ban-types
-    [path: string]: SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[] | SchemaDefinition | SchemaDefinition[];
-  }
+  type SchemaDefinitionProperty<T = undefined> = SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[] | SchemaDefinition<T> | SchemaDefinition<T>[];
+
+  type SchemaDefinition<T = undefined> = T extends undefined
+    ? { [path: string]: SchemaDefinitionProperty; }
+    : { [path in keyof T]-?: SchemaDefinitionProperty<T[path]>; };
 
   interface SchemaOptions {
     /**

From c2f90f2f4873bc0c71e788a90dfabc6afc4bed1a Mon Sep 17 00:00:00 2001
From: Vorticalbox <vorticalbox@protonmail.com>
Date: Mon, 4 Jan 2021 15:44:22 +0000
Subject: [PATCH 1569/2348] Add missing projection typing

Adds missing project function to Aggregate
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index dd86ac89657..f7fbd920906 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2349,6 +2349,9 @@ declare module 'mongoose' {
 
     /** Appends new custom $unwind operator(s) to this aggregate pipeline. */
     unwind(...args: any[]): this;
+                                          
+    /** Appends new custom $project operator to this aggregate pipeline. */
+    project(arg: any): this
   }
 
   class AggregationCursor extends stream.Readable {

From be93a716540eeba58ae60e9ffff5ba9246fd0caa Mon Sep 17 00:00:00 2001
From: vorticalbox <vorticalbox@protonmail.com>
Date: Mon, 4 Jan 2021 16:01:15 +0000
Subject: [PATCH 1570/2348] remove: trailing white space

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index f7fbd920906..14dc462822d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2349,7 +2349,7 @@ declare module 'mongoose' {
 
     /** Appends new custom $unwind operator(s) to this aggregate pipeline. */
     unwind(...args: any[]): this;
-                                          
+
     /** Appends new custom $project operator to this aggregate pipeline. */
     project(arg: any): this
   }

From a31efa18311a8f054728d26199756109dfa42f1a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 4 Jan 2021 11:50:33 -0500
Subject: [PATCH 1571/2348] feat (document): Exposed $getAllSubdocs()

---
 index.d.ts                   |  6 +++---
 lib/document.js              | 12 ++++++------
 lib/model.js                 |  2 +-
 lib/plugins/removeSubdocs.js |  2 +-
 lib/plugins/saveSubdocs.js   |  4 ++--
 5 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 14dc462822d..8bce9465189 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -375,6 +375,9 @@ declare module 'mongoose' {
     /** This documents __v. */
     __v?: number;
 
+    /* Get all subdocs (by bfs) */
+    $getAllSubdocs(): Document[];
+
     /** Don't run validation on this path or persist changes to this path. */
     $ignore(path: string): void;
 
@@ -2349,9 +2352,6 @@ declare module 'mongoose' {
 
     /** Appends new custom $unwind operator(s) to this aggregate pipeline. */
     unwind(...args: any[]): this;
-
-    /** Appends new custom $project operator to this aggregate pipeline. */
-    project(arg: any): this
   }
 
   class AggregationCursor extends stream.Readable {
diff --git a/lib/document.js b/lib/document.js
index b127476a24a..9e3cc3c79d2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -843,7 +843,7 @@ Document.prototype.$session = function $session(session) {
   this.$__.session = session;
 
   if (!this.ownerDocument) {
-    const subdocs = this.$__getAllSubdocs();
+    const subdocs = this.$getAllSubdocs();
     for (const child of subdocs) {
       child.$session(session);
     }
@@ -2271,7 +2271,7 @@ function _getPathsToValidate(doc) {
   Object.keys(doc.$__.activePaths.states.default).forEach(addToPaths);
   function addToPaths(p) { paths.add(p); }
 
-  const subdocs = doc.$__getAllSubdocs();
+  const subdocs = doc.$getAllSubdocs();
   const modifiedPaths = doc.modifiedPaths();
   for (const subdoc of subdocs) {
     if (subdoc.$basePath) {
@@ -2942,7 +2942,7 @@ Document.prototype.$__undoReset = function $__undoReset() {
     }
   }
 
-  for (const subdoc of this.$__getAllSubdocs()) {
+  for (const subdoc of this.$getAllSubdocs()) {
     subdoc.$__undoReset();
   }
 };
@@ -3070,13 +3070,13 @@ Document.prototype.$__getArrayPathsToValidate = function() {
 /**
  * Get all subdocs (by bfs)
  *
- * @api private
- * @method $__getAllSubdocs
+ * @api public
+ * @method $getAllSubdocs
  * @memberOf Document
  * @instance
  */
 
-Document.prototype.$__getAllSubdocs = function() {
+Document.prototype.$getAllSubdocs = function $getAllSubdocs() {
   DocumentArray || (DocumentArray = require('./types/documentarray'));
   Embedded = Embedded || require('./types/embedded');
 
diff --git a/lib/model.js b/lib/model.js
index cec00dc480f..c7854da9ad6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3386,7 +3386,7 @@ function _setIsNew(doc, val) {
   doc.emit('isNew', val);
   doc.constructor.emit('isNew', val);
 
-  const subdocs = doc.$__getAllSubdocs();
+  const subdocs = doc.$getAllSubdocs();
   for (const subdoc of subdocs) {
     subdoc.isNew = val;
   }
diff --git a/lib/plugins/removeSubdocs.js b/lib/plugins/removeSubdocs.js
index 44b2ea62790..6bf030c36af 100644
--- a/lib/plugins/removeSubdocs.js
+++ b/lib/plugins/removeSubdocs.js
@@ -15,7 +15,7 @@ module.exports = function(schema) {
     }
 
     const _this = this;
-    const subdocs = this.$__getAllSubdocs();
+    const subdocs = this.$getAllSubdocs();
 
     each(subdocs, function(subdoc, cb) {
       subdoc.$__remove(cb);
diff --git a/lib/plugins/saveSubdocs.js b/lib/plugins/saveSubdocs.js
index c0a3144e778..33665caf339 100644
--- a/lib/plugins/saveSubdocs.js
+++ b/lib/plugins/saveSubdocs.js
@@ -15,7 +15,7 @@ module.exports = function(schema) {
     }
 
     const _this = this;
-    const subdocs = this.$__getAllSubdocs();
+    const subdocs = this.$getAllSubdocs();
 
     if (!subdocs.length) {
       next();
@@ -43,7 +43,7 @@ module.exports = function(schema) {
     }
 
     const _this = this;
-    const subdocs = this.$__getAllSubdocs();
+    const subdocs = this.$getAllSubdocs();
 
     if (!subdocs.length) {
       next();

From 0a256402b8f2e1ec4821636ffcd6e5e9eee3417f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 4 Jan 2021 14:40:04 -0500
Subject: [PATCH 1572/2348] chore: release 5.11.10

---
 History.md   | 20 ++++++++++++++++++++
 package.json |  2 +-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 087bb709e6f..1a046c0130e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,23 @@
+5.11.10 / 2020-01-04
+====================
+ * fix(model): support `populate` option for `insertMany()` as a workaround for mongoose-autopopulate #9720
+ * perf(schema): avoid creating extra array when initializing array of arrays #9588
+ * perf(schema): avoid setting `arrayPath` when casting to a non-array, avoid unnecessarily setting atomics #9588
+ * perf(schema): avoid expensive `String#slice()` call when creating a new array #9588
+ * fix(queryhelpers): avoid modifying `lean.virtuals` in place #9754
+ * fix: fall back to legacy treatment for square brackets if square brackets contents aren't a number #9640
+ * fix(document): make fix for #9396 handle null values more gracefully #9709
+ * fix(index.d.ts): add missing overloaded function for Document#populate() #9744 [sahasayan](https://github.com/sahasayan)
+ * fix(index.d.ts): allow Model.create param1 overwrite #9753 [hasezoey](https://github.com/hasezoey)
+ * fix(index.d.ts): improve autocomplete for query middleware #9752 [3Aahmednaser94](https://github.com/3Aahmednaser94)
+ * fix(index.d.ts): add missing function for Aggregate#group() #9750 [coro101](https://github.com/coro101)
+ * fix(index.d.ts): add missing `Aggregate#project()` #9763 [vorticalbox](https://github.com/vorticalbox)
+ * fix(index.d.ts): allow `null` as an enum value for schematypes #9746
+ * docs(guide+schema): make schema API docs and guide docs' list of Schema options line up #9749
+ * docs(documents): add some more details about what the `save()` promise resolves to #9689
+ * docs(subdocs): add section about subdocument defaults #7291
+ * chore: run GitHub CI on PRs and update badge #9760 [YC](https://github.com/YC)
+
 5.11.9 / 2020-12-28
 ===================
  * fix(document): keeps atomics when assigning array to filtered array #9651
diff --git a/package.json b/package.json
index e52fbbd9838..92f6b9efc50 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.9",
+  "version": "5.11.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From ec5c540ce086230ec04a926c7f79ebb81363b1b2 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 4 Jan 2021 18:30:11 -0500
Subject: [PATCH 1573/2348] feat: implemented getPopulatedDocs()

---
 lib/document.js       | 20 ++++++++++++++++++++
 test/document.test.js | 31 +++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index b127476a24a..ab0e1b1e249 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3128,6 +3128,8 @@ Document.prototype.$__getAllSubdocs = function() {
   return subDocs;
 };
 
+
+
 /*!
  * Runs queued functions
  */
@@ -3897,6 +3899,24 @@ Document.prototype.populate = function populate() {
   return this;
 };
 
+/* Returns an array of all populated documents associated with the query. */
+Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
+  const index = (Object.keys(this.$__.populated));
+  // console.log(index);
+  let result = [];
+
+  for (const key of index) {
+    let value = this.get(key);
+    if (Array.isArray(value)) result = result.concat(value);
+    else if (typeof value === 'object' && value !== null)
+      result.push(value);
+
+  }
+  console.log(result);
+  return result;
+
+};
+
 /**
  * Explicitly executes population and returns a promise. Useful for promises integration.
  *
diff --git a/test/document.test.js b/test/document.test.js
index 6949d55d824..ba6f68c553f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9834,4 +9834,35 @@ describe('document', function() {
       assert.equal(fromDb.arr[0].abc, 'ghi');
     });
   });
+
+  it('supports getting a list of populated docs (gh-9702)', function() {
+    const Child = db.model('Child', Schema({ name: String }));
+    const Parent = db.model('Parent', {
+    children: [{ type: ObjectId, ref: 'Child' }],
+    child: {type: ObjectId, ref: 'Child'}
+    });
+    
+    return co(function*() {
+    const c = yield Child.create({ name: 'test' });
+    yield Parent.create({
+    children: [c._id],
+    child: c._id
+    });
+    
+    const p = yield Parent.findOne().populate('children child');
+    
+    p.children; // [{ _id: '...', name: 'test' }]
+    
+    assert.equal(p.$getPopulatedDocs().length, 1);
+    assert.equal(p.$getPopulatedDocs()[0], p.children[0]);
+    assert.equal(p.$getPopulatedDocs()[0].name, 'test');
+    });
+    });
+
 });
+
+
+
+
+
+  

From 2ca7abdf7c7b105d84cbed289c343b6d1b9b1e6d Mon Sep 17 00:00:00 2001
From: Fernando <60452941+Fernando-Lozano@users.noreply.github.com>
Date: Mon, 4 Jan 2021 19:57:37 -0600
Subject: [PATCH 1574/2348] Added recommended connection option.

"You should set this option to true, except for the unlikely case that it prevents you from maintaining a stable connection."
---
 docs/index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/index.pug b/docs/index.pug
index 133926c9503..a1c0ecb06f2 100644
--- a/docs/index.pug
+++ b/docs/index.pug
@@ -32,7 +32,7 @@ block content
     ```javascript
     // getting-started.js
     const mongoose = require('mongoose');
-    mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true});
+    mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true, useUnifiedTopology: true});
     ```
 
     We have a pending connection to the test database running on localhost.

From 29149ddea903af63ea963046dd4b9fad2975c40c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Jan 2021 09:16:45 -0500
Subject: [PATCH 1575/2348] fix(index.d.ts): ensure TypeScript knows that
 `this` refers to `DocType` in schema methods with strict  mode

Fix #9755
---
 index.d.ts                   | 2 +-
 test/typescript/main.test.js | 2 +-
 test/typescript/methods.ts   | 3 ++-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 14dc462822d..b5544eddca6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1090,7 +1090,7 @@ declare module 'mongoose' {
     method(obj: { [name: string]: Function }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [name: string]: Function };
+    methods: { [name: string]: (this: DocType, ...args: any[]) => void };
 
     /** The original object passed to the schema constructor */
     obj: any;
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 70e9d8ae3c0..dcd3f2a038c 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -166,7 +166,7 @@ describe('typescript syntax', function() {
   });
 
   it('methods', function() {
-    const errors = runTest('methods.ts');
+    const errors = runTest('methods.ts', { strict: true });
     if (process.env.D && errors.length) {
       console.log(errors);
     }
diff --git a/test/typescript/methods.ts b/test/typescript/methods.ts
index c39bf24243d..9a77bc00d39 100644
--- a/test/typescript/methods.ts
+++ b/test/typescript/methods.ts
@@ -5,11 +5,12 @@ interface ITest extends Document {
   getAnswer(): number;
 }
 
-const TestSchema = new Schema({
+const TestSchema = new Schema<ITest>({
   foo: { type: String, required: true }
 });
 
 TestSchema.methods.getAnswer = function(): number {
+  console.log(this.foo.trim());
   return 42;
 };
 

From 2990fb6a98d101e57d3906a8bf97fa9be20af495 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 10:29:01 -0500
Subject: [PATCH 1576/2348] fix: edited formatting of document..test.js and
 document.js

---
 lib/document.js       | 21 ++++++++++-----------
 test/document.test.js | 36 ++++++++++++++++++------------------
 2 files changed, 28 insertions(+), 29 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index ab0e1b1e249..d4dbc4ccc28 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3901,20 +3901,19 @@ Document.prototype.populate = function populate() {
 
 /* Returns an array of all populated documents associated with the query. */
 Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
-  const index = (Object.keys(this.$__.populated));
-  // console.log(index);
-  let result = [];
-
-  for (const key of index) {
-    let value = this.get(key);
-    if (Array.isArray(value)) result = result.concat(value);
-    else if (typeof value === 'object' && value !== null)
-      result.push(value);
+  const pathway = (Object.keys(this.$__.populated));
+  const result = [];
 
+  for (const key of pathway) {
+    const value = this.get(key);
+    if (Array.isArray(value)){
+      result = result.concat(value);
+    }
+    else if (typeof value === 'object' && value !== null){
+      result.push(value);
+    } 
   }
-  console.log(result);
   return result;
-
 };
 
 /**
diff --git a/test/document.test.js b/test/document.test.js
index ba6f68c553f..91ee551ce81 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9838,26 +9838,26 @@ describe('document', function() {
   it('supports getting a list of populated docs (gh-9702)', function() {
     const Child = db.model('Child', Schema({ name: String }));
     const Parent = db.model('Parent', {
-    children: [{ type: ObjectId, ref: 'Child' }],
-    child: {type: ObjectId, ref: 'Child'}
+      children: [{ type: ObjectId, ref: 'Child' }],
+      child: { type: ObjectId, ref: 'Child' }
     });
-    
+
     return co(function*() {
-    const c = yield Child.create({ name: 'test' });
-    yield Parent.create({
-    children: [c._id],
-    child: c._id
-    });
-    
-    const p = yield Parent.findOne().populate('children child');
-    
-    p.children; // [{ _id: '...', name: 'test' }]
-    
-    assert.equal(p.$getPopulatedDocs().length, 1);
-    assert.equal(p.$getPopulatedDocs()[0], p.children[0]);
-    assert.equal(p.$getPopulatedDocs()[0].name, 'test');
-    });
+      const c = yield Child.create({ name: 'test' });
+      yield Parent.create({
+        children: [c._id],
+        child: c._id
+      });
+
+      const p = yield Parent.findOne().populate('children child');
+
+      p.children; // [{ _id: '...', name: 'test' }]
+
+      assert.equal(p.$getPopulatedDocs().length, 2);
+      assert.equal(p.$getPopulatedDocs()[0], p.children[0]);
+      assert.equal(p.$getPopulatedDocs()[0].name, 'test');
     });
+  });
 
 });
 
@@ -9865,4 +9865,4 @@ describe('document', function() {
 
 
 
-  
+

From f81e95b1e05b66f82bd99d319e6ecc9d9999226b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 10:36:20 -0500
Subject: [PATCH 1577/2348] fix: changed const result = [] to let result = []

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index d4dbc4ccc28..5baeb72c142 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3902,7 +3902,7 @@ Document.prototype.populate = function populate() {
 /* Returns an array of all populated documents associated with the query. */
 Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
   const pathway = (Object.keys(this.$__.populated));
-  const result = [];
+  let result = [];
 
   for (const key of pathway) {
     const value = this.get(key);

From 88616e487586f653369c506fbf6e91b093ff5f13 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 10:37:53 -0500
Subject: [PATCH 1578/2348] fix: re-edited formatting

---
 lib/document.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 5baeb72c142..c5f831b7813 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3906,10 +3906,10 @@ Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
 
   for (const key of pathway) {
     const value = this.get(key);
-    if (Array.isArray(value)){
+    if (Array.isArray(value)) {
       result = result.concat(value);
     }
-    else if (typeof value === 'object' && value !== null){
+    else if (typeof value === 'object' && value !== null) {
       result.push(value);
     } 
   }

From 5c6993f1d1bb6666f40d8647f9ce3a06c9e22528 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 10:50:29 -0500
Subject: [PATCH 1579/2348] fix: edited formatting

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index c5f831b7813..f528b13905d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3911,7 +3911,7 @@ Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
     }
     else if (typeof value === 'object' && value !== null) {
       result.push(value);
-    } 
+    }
   }
   return result;
 };

From 5e8e7f7e3d1f83c6163329bdaa6f9cab4a480c16 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 13:28:22 -0500
Subject: [PATCH 1580/2348] feat: implemented getPopulatedDocs()

---
 lib/document.js       |  5 ++---
 test/document.test.js | 11 +++--------
 2 files changed, 5 insertions(+), 11 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f528b13905d..bcf8eb23989 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3901,10 +3901,9 @@ Document.prototype.populate = function populate() {
 
 /* Returns an array of all populated documents associated with the query. */
 Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
-  const pathway = (Object.keys(this.$__.populated));
+  const keys = (Object.keys(this.$__.populated));
   let result = [];
-
-  for (const key of pathway) {
+  for (const key of keys) {
     const value = this.get(key);
     if (Array.isArray(value)) {
       result = result.concat(value);
diff --git a/test/document.test.js b/test/document.test.js
index 91ee551ce81..02363dc0113 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9856,13 +9856,8 @@ describe('document', function() {
       assert.equal(p.$getPopulatedDocs().length, 2);
       assert.equal(p.$getPopulatedDocs()[0], p.children[0]);
       assert.equal(p.$getPopulatedDocs()[0].name, 'test');
+      assert.equal(p.$getPopulatedDocs()[1],p.child);
+      assert.equal(p.$getPopulatedDocs()[1].name, 'test');
     });
   });
-
-});
-
-
-
-
-
-
+});
\ No newline at end of file

From 9a102d19e331c05ed9fdfe165a1182a730327e72 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 13:45:16 -0500
Subject: [PATCH 1581/2348] feat: added $getPopulatedDocs to index.d.ts

---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 14dc462822d..b0cd3d7ceb6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -384,6 +384,9 @@ declare module 'mongoose' {
     /** Getter/setter, determines whether the document was removed or not. */
     $isDeleted(val?: boolean): boolean;
 
+    /** Returns an array of all populated documents associated with the query */
+    $getPopulatedDocs(): Document[];
+
     /**
      * Returns true if the given path is nullish or only contains empty objects.
      * Useful for determining whether this subdoc will get stripped out by the

From ef3038e0746947fed40e71fb2c1524aec7c875bc Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 17:20:56 -0500
Subject: [PATCH 1582/2348] feat: Implemented setting explain flag

---
 lib/query.js       |  5 +++--
 test/model.test.js | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index ce49c4cdb14..c79027910fe 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1338,7 +1338,6 @@ Query.prototype.setOptions = function(options, overwrite) {
     }
     return this;
   }
-
   if (options == null) {
     return this;
   }
@@ -1354,7 +1353,9 @@ Query.prototype.setOptions = function(options, overwrite) {
       this.populate(populate[i]);
     }
   }
-
+  if ('explain' in options) {
+    this.explain(this.mongooseOptions);
+  }
   if ('useFindAndModify' in options) {
     this._mongooseOptions.useFindAndModify = options.useFindAndModify;
     delete options.useFindAndModify;
diff --git a/test/model.test.js b/test/model.test.js
index 59bfc680911..a1ae07dfb80 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7082,5 +7082,24 @@ describe('Model', function() {
         assert.equal(user3.name, 'Hafez2');
       });
     });
+
+    it('should set the explain flag on the query (gh-8075)', function() {
+      return co(function*() {
+        const MyModel = mongoose.model('Character', mongoose.Schema({
+          name: String,
+          age: Number,
+          rank: String
+        }));
+        
+        MyModel.create([
+          { name: 'Jean-Luc Picard', age: 59, rank: 'Captain' },
+          { name: 'William Riker', age: 29, rank: 'Commander' },
+          { name: 'Deanna Troi', age: 28, rank: 'Lieutenant Commander' },
+          { name: 'Geordi La Forge', age: 29, rank: 'Lieutenant' },
+          { name: 'Worf', age: 24, rank: 'Lieutenant' }
+        ]);
+        assert.equal(typeof MyModel.exists({}, {explain: true}), 'object');
+      });
+    });
   });
 });

From 538cd512a7fa572a714e9d3bffcab0e63cfc0c2e Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 5 Jan 2021 17:27:31 -0500
Subject: [PATCH 1583/2348] Update model.test.js

---
 test/model.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index a1ae07dfb80..a6f31b9a389 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7090,7 +7090,7 @@ describe('Model', function() {
           age: Number,
           rank: String
         }));
-        
+
         MyModel.create([
           { name: 'Jean-Luc Picard', age: 59, rank: 'Captain' },
           { name: 'William Riker', age: 29, rank: 'Commander' },
@@ -7098,7 +7098,7 @@ describe('Model', function() {
           { name: 'Geordi La Forge', age: 29, rank: 'Lieutenant' },
           { name: 'Worf', age: 24, rank: 'Lieutenant' }
         ]);
-        assert.equal(typeof MyModel.exists({}, {explain: true}), 'object');
+        assert.equal(typeof MyModel.exists({}, { explain: true }), 'object');
       });
     });
   });

From dd132ee4fe9aa516cdde6145a21d47f6a8514f62 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Jan 2021 14:06:20 -0500
Subject: [PATCH 1584/2348] fix(model): support calling `create()` with
 `undefined` as first argument and no callback

Fix #9765
---
 lib/model.js              |  2 +-
 test/model.create.test.js | 10 +++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index cec00dc480f..cf8bdfff7fc 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3000,7 +3000,7 @@ Model.create = function create(doc, options, callback) {
     const last = arguments[arguments.length - 1];
     options = {};
     // Handle falsy callbacks re: #5061
-    if (typeof last === 'function' || !last) {
+    if (typeof last === 'function' || (arguments.length > 1 && !last)) {
       cb = last;
       args = utils.args(arguments, 0, arguments.length - 1);
     } else {
diff --git a/test/model.create.test.js b/test/model.create.test.js
index c6097f639de..eb0744d8027 100644
--- a/test/model.create.test.js
+++ b/test/model.create.test.js
@@ -17,7 +17,7 @@ const DocumentObjectId = mongoose.Types.ObjectId;
  */
 
 const schema = new Schema({
-  title: { type: String, required: true }
+  title: { type: String }
 });
 
 describe('model', function() {
@@ -187,6 +187,14 @@ describe('model', function() {
           }).
           catch(done);
       });
+
+      it('treats undefined first arg as doc rather than callback (gh-9765)', function() {
+        return B.create(void 0).
+          then(function(doc) {
+            assert.ok(doc);
+            assert.ok(doc._id);
+          });
+      });
     });
   });
 });

From bd1f6e9b91e09f671126f6d63ac475df3cf3256b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Jan 2021 14:19:54 -0500
Subject: [PATCH 1585/2348] fix(index.d.ts): allow setting `min` and `max` to
 [number, string] and [Date, string]

Fix #9762
---
 index.d.ts                | 4 ++--
 test/typescript/schema.ts | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 826b0b2f84e..03c86dcd2f9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1417,10 +1417,10 @@ declare module 'mongoose' {
     subtype?: number
 
     /** The minimum value allowed for this path. Only allowed for numbers and dates. */
-    min?: number | Date;
+    min?: number | Date | [number, string] | [Date, string];
 
     /** The maximum value allowed for this path. Only allowed for numbers and dates. */
-    max?: number | Date;
+    max?: number | Date | [number, string] | [Date, string];
 
     /** Defines a TTL index on this path. Only allowed for dates. */
     expires?: number | Date;
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 85d35a4b94e..6c9b10488ae 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -6,5 +6,11 @@ const schema: Schema = new Schema({
     type: String,
     enum: ['Test', null],
     default: null
+  },
+  numberWithMax: {
+    type: Number,
+    required: [true, 'Required'],
+    min: [0, 'MinValue'],
+    max: [24, 'MaxValue']
   }
 });

From 8066fd268fb23cc43e1ea83584ac389f7506431b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 6 Jan 2021 14:22:34 -0500
Subject: [PATCH 1586/2348] chore: ask for tsconfig.json when opening a new
 issue

---
 .github/ISSUE_TEMPLATE.md | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/.github/ISSUE_TEMPLATE.md b/.github/ISSUE_TEMPLATE.md
index 4d5d263c401..b5e10873385 100644
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -5,7 +5,9 @@
 **What is the current behavior?**
 
 **If the current behavior is a bug, please provide the steps to reproduce.**
-<!-- If you can, provide a standalone script / gist to reproduce your issue -->
+<!-- If you can, provide a standalone script / gist to reproduce your issue. -->
+
+<!-- If you are using TypeScript, please include your `tsconfig.json` -->
 
 **What is the expected behavior?**
 

From 485c910eb8ab97a3632464f6f10a50cd81a824af Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 6 Jan 2021 15:14:44 -0500
Subject: [PATCH 1587/2348] fix: added space to fix linter error

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 02363dc0113..204b36c2b4e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9856,7 +9856,7 @@ describe('document', function() {
       assert.equal(p.$getPopulatedDocs().length, 2);
       assert.equal(p.$getPopulatedDocs()[0], p.children[0]);
       assert.equal(p.$getPopulatedDocs()[0].name, 'test');
-      assert.equal(p.$getPopulatedDocs()[1],p.child);
+      assert.equal(p.$getPopulatedDocs()[1], p.child);
       assert.equal(p.$getPopulatedDocs()[1].name, 'test');
     });
   });

From e8717488d3a821d9af6377040b147ce429144759 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 7 Jan 2021 12:33:04 -0500
Subject: [PATCH 1588/2348] PR for mongoose

---
 lib/model.js       |  1 -
 lib/query.js       | 15 ++++++++++++++-
 test/model.test.js | 10 ++++++----
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index cec00dc480f..6bbe5557c9d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1059,7 +1059,6 @@ Model.prototype.model = function model(name) {
 
 Model.exists = function exists(filter, options, callback) {
   _checkContext(this, 'exists');
-
   if (typeof options === 'function') {
     callback = options;
     options = null;
diff --git a/lib/query.js b/lib/query.js
index c79027910fe..edd0acb669e 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1354,7 +1354,14 @@ Query.prototype.setOptions = function(options, overwrite) {
     }
   }
   if ('explain' in options) {
-    this.explain(this.mongooseOptions);
+    console.log('Start');
+    console.log(options);
+    console.log(typeof options);
+    this.explain(options);
+    /*
+    this._mongooseOptions.explain = options.explain;
+    delete options.explain;
+    */
   }
   if ('useFindAndModify' in options) {
     this._mongooseOptions.useFindAndModify = options.useFindAndModify;
@@ -1400,6 +1407,12 @@ Query.prototype.explain = function(verbose) {
     this.options.explain = true;
     return this;
   }
+  console.log('outside block');
+  console.log('Yo ', verbose);
+  console.log(typeof verbose);
+  // verbose = Object(verbose);
+  console.log('New', verbose);
+  console.log(typeof verbose);
   this.options.explain = verbose;
   return this;
 };
diff --git a/test/model.test.js b/test/model.test.js
index a6f31b9a389..a2b80437aba 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7083,22 +7083,24 @@ describe('Model', function() {
       });
     });
 
-    it('should set the explain flag on the query (gh-8075)', function() {
+    it('should give an object back rather than a boolean (gh-8275)', function() {
       return co(function*() {
-        const MyModel = mongoose.model('Character', mongoose.Schema({
+        const MyModel = db.model('Character', mongoose.Schema({
           name: String,
           age: Number,
           rank: String
         }));
 
-        MyModel.create([
+        yield MyModel.create([
           { name: 'Jean-Luc Picard', age: 59, rank: 'Captain' },
           { name: 'William Riker', age: 29, rank: 'Commander' },
           { name: 'Deanna Troi', age: 28, rank: 'Lieutenant Commander' },
           { name: 'Geordi La Forge', age: 29, rank: 'Lieutenant' },
           { name: 'Worf', age: 24, rank: 'Lieutenant' }
         ]);
-        assert.equal(typeof MyModel.exists({}, { explain: true }), 'object');
+        const res = (yield MyModel.exists({}, { explain: true }));
+
+        assert.equal(typeof res, 'object');
       });
     });
   });

From c8072ef309af9abfc54474da41e42338c801cf55 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 7 Jan 2021 13:45:29 -0500
Subject: [PATCH 1589/2348] fix: explain will now return an object

I think I did it
---
 lib/model.js       |  8 ++++++--
 lib/query.js       | 17 +----------------
 test/model.test.js |  5 +++--
 3 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 6bbe5557c9d..0eb2ffe32d1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1078,8 +1078,12 @@ Model.exists = function exists(filter, options, callback) {
     });
     return;
   }
-
-  return query.then(doc => !!doc);
+  if (!('explain' in options)) {
+    return query.then(doc => !!doc);
+  }
+  else {
+    return query.then(doc => doc);
+  }
 };
 
 /**
diff --git a/lib/query.js b/lib/query.js
index edd0acb669e..0cc420b9200 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1353,16 +1353,7 @@ Query.prototype.setOptions = function(options, overwrite) {
       this.populate(populate[i]);
     }
   }
-  if ('explain' in options) {
-    console.log('Start');
-    console.log(options);
-    console.log(typeof options);
-    this.explain(options);
-    /*
-    this._mongooseOptions.explain = options.explain;
-    delete options.explain;
-    */
-  }
+
   if ('useFindAndModify' in options) {
     this._mongooseOptions.useFindAndModify = options.useFindAndModify;
     delete options.useFindAndModify;
@@ -1407,12 +1398,6 @@ Query.prototype.explain = function(verbose) {
     this.options.explain = true;
     return this;
   }
-  console.log('outside block');
-  console.log('Yo ', verbose);
-  console.log(typeof verbose);
-  // verbose = Object(verbose);
-  console.log('New', verbose);
-  console.log(typeof verbose);
   this.options.explain = verbose;
   return this;
 };
diff --git a/test/model.test.js b/test/model.test.js
index a2b80437aba..818a23a79dc 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7082,7 +7082,8 @@ describe('Model', function() {
         assert.equal(user3.name, 'Hafez2');
       });
     });
-
+  });
+  describe('Setting the explain flag', function() {
     it('should give an object back rather than a boolean (gh-8275)', function() {
       return co(function*() {
         const MyModel = db.model('Character', mongoose.Schema({
@@ -7098,7 +7099,7 @@ describe('Model', function() {
           { name: 'Geordi La Forge', age: 29, rank: 'Lieutenant' },
           { name: 'Worf', age: 24, rank: 'Lieutenant' }
         ]);
-        const res = (yield MyModel.exists({}, { explain: true }));
+        const res = yield MyModel.exists({}, { explain: true });
 
         assert.equal(typeof res, 'object');
       });

From 97a4877b13f41e3126486e78e747a70bf7a2c185 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 7 Jan 2021 14:17:36 -0500
Subject: [PATCH 1590/2348] added second condition to check for undefined

---
 lib/model.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 0eb2ffe32d1..e6ddb7060aa 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1078,7 +1078,8 @@ Model.exists = function exists(filter, options, callback) {
     });
     return;
   }
-  if (!('explain' in options)) {
+  console.log(options);
+  if (typeof options != undefined && !('explain' in options)) {
     return query.then(doc => !!doc);
   }
   else {

From 14cbfd9bb7abc8225fd4b0bb25c3448de345724a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 7 Jan 2021 14:34:45 -0500
Subject: [PATCH 1591/2348] separated if statments

---
 lib/model.js | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index e6ddb7060aa..5b7809d018e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1079,12 +1079,15 @@ Model.exists = function exists(filter, options, callback) {
     return;
   }
   console.log(options);
-  if (typeof options != undefined && !('explain' in options)) {
-    return query.then(doc => !!doc);
-  }
-  else {
-    return query.then(doc => doc);
+  if (typeof options != undefined) {
+    if (!('explain' in options)) {
+      return query.then(doc => !!doc);
+    }
+    else {
+      return query.then(doc => doc);
+    }
   }
+  return query.then(doc => !!doc);
 };
 
 /**

From 758bef75d01595f71192652672e9cbee70a14034 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 7 Jan 2021 14:37:57 -0500
Subject: [PATCH 1592/2348] fixed syntax error

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 5b7809d018e..43a82e1f3c2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1079,7 +1079,7 @@ Model.exists = function exists(filter, options, callback) {
     return;
   }
   console.log(options);
-  if (typeof options != undefined) {
+  if (typeof options !== 'undefined') {
     if (!('explain' in options)) {
       return query.then(doc => !!doc);
     }

From f632a6ab0be97c017ef895938faac4d259f5c217 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 7 Jan 2021 15:05:18 -0500
Subject: [PATCH 1593/2348] made requested changes

---
 lib/model.js | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 43a82e1f3c2..a208d1d3dbd 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1078,16 +1078,12 @@ Model.exists = function exists(filter, options, callback) {
     });
     return;
   }
-  console.log(options);
-  if (typeof options !== 'undefined') {
-    if (!('explain' in options)) {
-      return query.then(doc => !!doc);
-    }
-    else {
-      return query.then(doc => doc);
-    }
+  options = options || {};
+  if (!options.explain) {
+    return query.then(doc => !!doc);
+  } else {
+    return query.then(doc => doc);
   }
-  return query.then(doc => !!doc);
 };
 
 /**

From 81aec3baddbb0310987452b07b31f2dc2c5e83e1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 7 Jan 2021 18:18:14 -0500
Subject: [PATCH 1594/2348] fix(index.d.ts): add `Aggregate#addFields()`

Fix #9774
---
 index.d.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 03c86dcd2f9..02ffecaa4cf 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2240,6 +2240,12 @@ declare module 'mongoose' {
      * future release. */
     addCursorFlag(flag: string, value: boolean): this;
 
+    /**
+     * Appends a new $addFields operator to this aggregate pipeline.
+     * Requires MongoDB v3.4+ to work
+     */
+    addFields(arg: any): this;
+
     /** Sets the allowDiskUse option for the aggregation query (ignored for < 2.6.0) */
     allowDiskUse(value: boolean): this;
 

From dbbd444a02fb616c1ea26465c6d4214de88f5b17 Mon Sep 17 00:00:00 2001
From: Ben Botvinick <benbotvinick@gmail.com>
Date: Fri, 8 Jan 2021 00:00:18 -0500
Subject: [PATCH 1595/2348] Correct improper date in History.md

---
 History.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 1a046c0130e..f20b8e316a3 100644
--- a/History.md
+++ b/History.md
@@ -1,4 +1,4 @@
-5.11.10 / 2020-01-04
+5.11.10 / 2021-01-04
 ====================
  * fix(model): support `populate` option for `insertMany()` as a workaround for mongoose-autopopulate #9720
  * perf(schema): avoid creating extra array when initializing array of arrays #9588

From 8c17052d3c0113171c76aefdcd07199e23dace13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Jan 2021 11:04:55 -0500
Subject: [PATCH 1596/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 6e8a83bded6..5d6ac1b4ede 100644
--- a/index.pug
+++ b/index.pug
@@ -346,6 +346,9 @@ html(lang='en')
               <a rel="sponsored" href="https://njsportsjournal.com/">
                 <img class="sponsor" src="https://images.opencollective.com/njsj1/9bf603f/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://www.nettikasinot.media/">
+                <img class="sponsor" src="https://images.opencollective.com/nettikasinot-media/2dba7da/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 1e79cac45b1b514577ff39b3f16666718e744628 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Jan 2021 12:47:35 -0500
Subject: [PATCH 1597/2348] fix(index.d.ts): improve context and type bindings
 for `Schema#methods` and `Schema#statics`

Fix #9717
---
 index.d.ts | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 02ffecaa4cf..9769a80cedf 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1086,11 +1086,11 @@ declare module 'mongoose' {
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    method(name: string, fn: Function, opts?: any): this;
-    method(obj: { [name: string]: Function }): this;
+    method(name: string, fn: (this: DocType, ...args: any[]) => any, opts?: any): this;
+    method(obj: { [name: string]: (this: DocType, ...args: any[]) => any }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [name: string]: (this: DocType, ...args: any[]) => void };
+    methods: { [F in keyof DocType]: DocType[F] } & { [name: string]: (this: DocType, ...args: any[]) => any };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1144,12 +1144,12 @@ declare module 'mongoose' {
 
     /** Adds static "class" methods to Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    static(name: string, fn: Function): this;
+    static(name: string, fn: (this: M, ...args: any[]) => any): this;
     // eslint-disable-next-line @typescript-eslint/ban-types
-    static(obj: { [name: string]: Function }): this;
+    static(obj: { [name: string]: (this: M, ...args: any[]) => any }): this;
 
     /** Object of currently defined statics on this schema. */
-    statics: { [name: string]: Function };
+    statics: { [F in keyof M]: M[F] } & { [name: string]: (this: M, ...args: any[]) => any };
 
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;

From 8e128346f30efec770f5b18439deec929911ace8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 8 Jan 2021 12:53:14 -0500
Subject: [PATCH 1598/2348] chore: release 5.11.11

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f20b8e316a3..f28d0576bb6 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.11.11 / 2021-01-08
+====================
+ * fix(model): support calling `create()` with `undefined` as first argument and no callback #9765
+ * fix(index.d.ts): ensure TypeScript knows that `this` refers to `DocType` in schema methods with strict mode #9755
+ * fix(index.d.ts): make SchemaDefinition accept a model generic #9761 [mroohian](https://github.com/mroohian)
+ * fix(index.d.ts): add `Aggregate#addFields()` #9774
+ * fix(index.d.ts): allow setting `min` and `max` to [number, string] and [Date, string] #9762
+ * fix(index.d.ts): improve context and type bindings for `Schema#methods` and `Schema#statics` #9717
+ * docs: add recommended connection option #9768 [Fernando-Lozano](https://github.com/Fernando-Lozano)
+ * chore: correct improper date in History.md #9783 [botv](https://github.com/botv)
+
 5.11.10 / 2021-01-04
 ====================
  * fix(model): support `populate` option for `insertMany()` as a workaround for mongoose-autopopulate #9720
diff --git a/package.json b/package.json
index 92f6b9efc50..666062bd04b 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.10",
+  "version": "5.11.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 1db879a007301186e24deae4b5787c937f32c0d3 Mon Sep 17 00:00:00 2001
From: Reza Roohian <m.roohian87@gmail.com>
Date: Sat, 9 Jan 2021 14:52:08 +0100
Subject: [PATCH 1599/2348] Fix the schema to accept typed SchemaDefinition

---
 index.d.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 9769a80cedf..bb0cb4be166 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1037,14 +1037,14 @@ declare module 'mongoose' {
 
   type MongooseQueryMiddleware = 'count' | 'deleteMany' | 'deleteOne' | 'find' | 'findOne' | 'findOneAndDelete' | 'findOneAndRemove' | 'findOneAndUpdate' | 'remove' | 'update' | 'updateOne' | 'updateMany';
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefModel = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
-    constructor(definition?: SchemaDefinition, options?: SchemaOptions);
+    constructor(definition?: SchemaDefinition<SchemaDefModel>, options?: SchemaOptions);
 
     /** Adds key path / schema type pairs to this schema. */
-    add(obj: SchemaDefinition | Schema, prefix?: string): this;
+    add(obj: SchemaDefinition<SchemaDefModel> | Schema, prefix?: string): this;
 
     /**
      * Array of child schemas (from document arrays and single nested subdocs)

From 266fedd2cb6e832703af0fa30acfa8c9592fbb74 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Jan 2021 12:03:50 -0500
Subject: [PATCH 1600/2348] perf(document): avoid creating extra array and
 double-applying setters when creating a nested array

Re: #9588
---
 lib/document.js       |  4 ++++
 lib/schematype.js     | 21 +--------------------
 test/document.test.js |  1 -
 3 files changed, 5 insertions(+), 21 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index b127476a24a..4b0de80070c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1234,6 +1234,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
     let didPopulate = false;
     if (refMatches && val instanceof Document) {
       this.populated(path, val._id, { [populateModelSymbol]: val.constructor });
+      val.$__.wasPopulated = true;
       didPopulate = true;
     }
 
@@ -1251,6 +1252,9 @@ Document.prototype.$set = function $set(path, val, type, options) {
         popOpts = { [populateModelSymbol]: val[0].constructor };
         this.populated(path, val.map(function(v) { return v._id; }), popOpts);
       }
+      for (const doc of val) {
+        doc.$__.wasPopulated = true;
+      }
       didPopulate = true;
     }
 
diff --git a/lib/schematype.js b/lib/schematype.js
index f54fbd9d92b..f6b7b1e0651 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1051,33 +1051,14 @@ SchemaType.prototype.getDefault = function(scope, init) {
  * @api private
  */
 
-SchemaType.prototype._applySetters = function(value, scope, init, priorVal) {
+SchemaType.prototype._applySetters = function(value, scope) {
   let v = value;
   const setters = this.setters;
-  const caster = this.caster;
 
   for (const setter of utils.clone(setters).reverse()) {
     v = setter.call(scope, v, this);
   }
 
-  if (caster && !caster.$isMongooseArray && Array.isArray(v) && caster.setters) {
-    const newVal = [];
-
-    for (let i = 0; i < v.length; ++i) {
-      const value = v[i];
-      try {
-        newVal.push(caster.applySetters(value, scope, init, priorVal));
-      } catch (err) {
-        if (err instanceof MongooseError.CastError) {
-          err.$originalErrorPath = err.path;
-          err.path = err.path + '.' + i;
-        }
-        throw err;
-      }
-    }
-    v = newVal;
-  }
-
   return v;
 };
 
diff --git a/test/document.test.js b/test/document.test.js
index 6949d55d824..aa6e01f2726 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -8942,7 +8942,6 @@ describe('document', function() {
     const err = t.validateSync();
     assert.ok(err);
     assert.ok(err.errors);
-    assert.ok(err.errors['test']);
     assert.ok(err.errors['test.1']);
   });
 

From b128819f86a2ed37661984398e8ac65ef4e21c84 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Jan 2021 12:10:40 -0500
Subject: [PATCH 1601/2348] test: clean up test failures for #9588

---
 test/schema.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 3c688226e56..2dbe512425a 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -441,7 +441,7 @@ describe('schema', function() {
         threw = true;
         assert.equal(error.name, 'CastError');
         assert.equal(error.message,
-          'Cast to [Number] failed for value "[["abcd"]]" at path "nums.0"');
+          'Cast to [[Number]] failed for value "[["abcd"]]" at path "nums.0"');
       }
       assert.ok(threw);
 

From f91e1297f0dd1561dff61a1196d321fa6c75034b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Jan 2021 12:45:22 -0500
Subject: [PATCH 1602/2348] test(queries): add test coverage for `$addToSet`
 and `$push` re: #9788

---
 test/typescript/queries.ts | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 1c935e46d13..ba391e90813 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,11 +1,12 @@
 import { Schema, model, Document, Types } from 'mongoose';
 
-const schema: Schema = new Schema({ name: { type: 'String' } });
+const schema: Schema = new Schema({ name: { type: 'String' }, tags: [String] });
 
 interface ITest extends Document {
   name?: string;
   age?: number;
   parent?: Types.ObjectId;
+  tags?: string[];
 }
 
 const Test = model<ITest>('Test', schema);
@@ -39,3 +40,6 @@ Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest |
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true }).then((res: ITest) => { res.name = 'test4'; });
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
+
+Test.findOneAndUpdate({ name: 'test' }, { $addToSet: { tags: 'each' } });
+Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
\ No newline at end of file

From c8a422d1ff1cdb9326e09df4c12d87e18a172f46 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Jan 2021 12:54:33 -0500
Subject: [PATCH 1603/2348] chore: couple quick style fixes

---
 lib/document.js | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index bcf8eb23989..7f0dc3598c4 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3128,8 +3128,6 @@ Document.prototype.$__getAllSubdocs = function() {
   return subDocs;
 };
 
-
-
 /*!
  * Runs queued functions
  */
@@ -3907,8 +3905,7 @@ Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
     const value = this.get(key);
     if (Array.isArray(value)) {
       result = result.concat(value);
-    }
-    else if (typeof value === 'object' && value !== null) {
+    } else if (value instanceof Document) {
       result.push(value);
     }
   }

From 3274823446462ba3f2622aaa31ac58939936aa93 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Jan 2021 13:07:29 -0500
Subject: [PATCH 1604/2348] chore: code review comments

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index a208d1d3dbd..3df2da23014 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1081,9 +1081,9 @@ Model.exists = function exists(filter, options, callback) {
   options = options || {};
   if (!options.explain) {
     return query.then(doc => !!doc);
-  } else {
-    return query.then(doc => doc);
   }
+  
+  return query.exec();
 };
 
 /**

From 7c7158c30c8bf690258e41712e09b8324406d7e9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 9 Jan 2021 13:11:45 -0500
Subject: [PATCH 1605/2348] style: fix lint

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index b3d5c97bb0b..b30c3a19ecb 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1082,7 +1082,7 @@ Model.exists = function exists(filter, options, callback) {
   if (!options.explain) {
     return query.then(doc => !!doc);
   }
-  
+
   return query.exec();
 };
 

From 2bc86a61a46610e75d52b401ff76f61064a88913 Mon Sep 17 00:00:00 2001
From: Henrique Borges <henriquelb96@gmail.com>
Date: Mon, 11 Jan 2021 10:12:03 -0300
Subject: [PATCH 1606/2348] Fix: removed the extra word on comment doc

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 9769a80cedf..200a08db8e2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2266,7 +2266,7 @@ declare module 'mongoose' {
     count(countName: string): this;
 
     /**
-     * Sets the cursor option option for the aggregation query (ignored for < 2.6.0).
+     * Sets the cursor option for the aggregation query (ignored for < 2.6.0).
      */
     cursor(options?: Record<string, unknown>): this;
 

From eca8374b50ed4b570afea3c40d498e9eb7e46122 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 11 Jan 2021 14:31:50 -0500
Subject: [PATCH 1607/2348] chore: add logo svg

---
 docs/images/mongoose.svg | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 docs/images/mongoose.svg

diff --git a/docs/images/mongoose.svg b/docs/images/mongoose.svg
new file mode 100644
index 00000000000..a230aefd1f9
--- /dev/null
+++ b/docs/images/mongoose.svg
@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:svg="http://www.w3.org/2000/svg" xmlns="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" version="1.1" id="svg2" xml:space="preserve" width="1280" height="746.66669" viewBox="0 0 1280 746.66669" sodipodi:docname="mongoose.svg" inkscape:version="1.0.1 (1.0.1+r75)">
+  <metadata id="metadata8">
+    <rdf:RDF>
+      <cc:Work rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type rdf:resource="http://purl.org/dc/dcmitype/StillImage"/>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <defs id="defs6">
+    <clipPath clipPathUnits="userSpaceOnUse" id="clipPath22">
+      <path d="M 0,560 H 960 V 0 H 0 Z" id="path20"/>
+    </clipPath>
+  </defs>
+  <sodipodi:namedview pagecolor="#ffffff" bordercolor="#666666" borderopacity="1" objecttolerance="10" gridtolerance="10" guidetolerance="10" inkscape:pageopacity="0" inkscape:pageshadow="2" inkscape:window-width="2227" inkscape:window-height="1205" id="namedview4" inkscape:document-rotation="0" showgrid="false" inkscape:zoom="0.85703125" inkscape:cx="528.80219" inkscape:cy="373.33334" inkscape:window-x="24" inkscape:window-y="132" inkscape:window-maximized="0" inkscape:current-layer="g18"/>
+  <g id="g10" inkscape:groupmode="layer" inkscape:label="FIVERRMONGOOSE" transform="matrix(2,0,0,-2,-340,1000)">
+    <g id="g12" transform="translate(439.8999,245.333)">
+      <path d="m 0,0 -23.9,37.117 v -66.45 h 46.403 l 1.597,1.636 v 64.814 z" style="fill:#880000;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path14"/>
+    </g>
+    <g id="g16">
+      <g id="g18" clip-path="url(#clipPath22)">
+        <g id="g24" transform="translate(662.1133,391.8979)">
+          <path
+            d="M 0 0 c -9.067 -0.676 -18.155 -1.376 -27.24 -1.429 c -5.592 -0.032 -11.28 0.698 -16.766 1.839 c -6.932 1.443 -12.758 4.878 -16.186 11.582 c -0.51 0.993 -2.217 1.565 -3.484 1.943 c -4.468 1.328 -8.986 2.485 -13.498 4.154 c 1.57 0.118 3.141 0.346 4.708 0.33 c 3.846 -0.038 7.735 0.142 11.522 -0.366 c 6.921 -0.928 13.787 -2.28 20.673 -3.475 c 3.924 -0.682 7.869 -1.296 11.761 -2.133 c 7.385 -1.589 14.744 -3.298 22.106 -4.989 C -1.539 6.339 3.315 5.182 8.168 4.007 M 1.769 -49.161 c -11.308 -3.485 -22.742 -6.62 -33.861 -10.63 c -6.961 -2.511 -13.502 -6.23 -20.12 -9.626 c -5.77 -2.958 -7.811 -8.009 -7.103 -14.28 c 0.457 -4.029 1.009 -8.047 1.371 -12.133 c -2.957 4.363 -5.141 9.082 -6.424 14.218 c -0.264 1.062 -0.515 2.128 -0.737 3.2 c -0.874 4.183 1.446 6.787 4.476 9.055 c 5.897 4.415 12.32 7.892 19.292 10.205 c 8.696 2.887 17.419 5.768 26.284 8.057 c 6.245 1.61 12.745 2.223 19.127 3.304 c 1.178 0.202 2.337 0.52 3.505 0.782 c 0.039 -0.16 0.079 -0.321 0.12 -0.481 c -1.977 -0.554 -3.97 -1.066 -5.93 -1.671 m -159.454 44.744 c -0.186 -0.182 -0.375 -0.362 -0.563 -0.542 c -5.042 3.677 -10.514 6.415 -16.51 8.003 c -0.168 -0.163 -0.332 -0.326 -0.496 -0.49 c 5.161 -6.048 10.323 -12.096 15.71 -18.404 c -3.607 1.18 -6.964 2.28 -10.322 3.379 c -0.143 -0.169 -0.284 -0.339 -0.428 -0.508 c 4.063 -6.694 9.353 -12.51 14.396 -19.22 c -8.768 4.979 -16.507 10.417 -23.731 16.595 c -9.916 8.481 -18.566 18.047 -25.046 29.439 c -2.669 4.694 -5.025 9.55 -5.529 15.043 c -0.113 1.226 -0.015 2.523 0.271 3.72 c 0.465 1.943 2.309 2.84 4.202 2.252 c 10.4 -3.233 20.622 -6.896 30.189 -12.211 c 9.056 -5.031 17.252 -11.153 24.303 -18.769 c 0.285 -0.308 0.496 -0.684 0.889 -1.236 c -5.521 2.516 -10.76 4.902 -16 7.289 c -0.177 -0.217 -0.353 -0.435 -0.532 -0.653 c 3.067 -4.562 6.132 -9.125 9.197 -13.687 m -315.372 -55.318 c -0.13 -0.353 0.276 -0.7 0.414 -1.049 c 2.156 0.453 4.293 1.045 6.47 1.339 c 0.568 0.075 1.136 0.147 1.705 0.223 c 8.034 2.863 16.264 5.112 24.762 6.31 c 12.011 1.691 24.463 3.936 36.722 3.87 c 11.648 -0.059 23.431 -1.843 34.828 -3.808 c 3.197 -0.55 6.336 -1.288 9.43 -2.158 c 8.326 -1.869 16.15 -5.203 23.182 -9.709 c 0.507 -0.242 1 -0.509 1.502 -0.763 c 9.998 -4.71 18.807 -11.639 25.763 -20.128 c 1.273 -1.409 3.492 -2.878 4.629 -4.42 c 2.396 -2.827 3.537 -5.839 7.537 -8.996 v 43.126 h 49.88 l 23.323 -43.036 l 23.392 43.036 h 51.405 v -83.351 l 8.509 5.611 c 0 0 9.33 24.806 52.556 28.289 l 49.544 1.602 c -7.642 15.819 -7.614 15.819 -3.929 20.591 c 3.649 4.722 31.792 7.818 36.742 10.771 l 72.297 14.587 c 0.17 0.556 0.363 -0.298 0.736 -0.181 c 1.799 0.567 3.663 0.924 6.233 1.529 l 16.35 3.979 c 1.064 0.599 2.331 0.836 3.504 1.242 c 7.64 2.652 14.321 6.068 18.018 14.208 c 3.6 7.93 8.421 15.296 10.169 24.018 c 0.551 2.759 0.076 5.157 -1.915 7.14 c -2.409 2.398 -5.516 3.428 -8.715 4.259 c -10.444 4.287 -20.85 8.676 -31.379 12.747 c -6.473 2.504 -13.114 4.582 -19.724 6.71 c -6.54 2.105 -13.117 4.092 -19.711 6.019 c -6.074 1.777 -12.185 3.429 -18.288 5.094 c -5.954 1.624 -11.9 3.295 -17.892 4.767 c -6.981 1.716 -14.01 3.243 -21.02 4.845 c -5.324 1.217 -10.628 2.519 -15.977 3.608 c -5.825 1.186 -11.687 2.206 -17.543 3.237 c -7.48 1.315 -14.944 2.773 -22.466 3.797 c -9.083 1.236 -18.224 2.036 -27.332 3.109 c -15.25 1.798 -30.54 2.28 -45.839 1.111 c -5.422 -0.414 -10.771 -1.788 -16.152 -2.722 c 5.7 -2.929 11.34 -5.298 16.903 -7.834 c 5.596 -2.551 10.813 -5.748 15.604 -9.607 c -6.269 2.4 -12.368 5.168 -18.655 7.413 c -13.121 4.684 -26.47 8.574 -40.333 10.45 c -6.781 0.917 -13.545 1.797 -20.32 -0.115 c -6.867 -1.938 -8.809 -4.486 -9.431 -11.377 c -1.03 -11.422 2.407 -22.016 6.972 -32.231 c 6.807 -15.232 16.728 -28.207 29.414 -39.057 c 9.714 -8.311 20.492 -14.861 32.398 -19.531 c 3.391 -1.33 6.815 -2.579 10.221 -3.866 c -0.077 -0.265 -0.154 -0.527 -0.231 -0.793 c -6.528 1.788 -13.221 3.128 -19.544 5.466 c -11.183 4.133 -21.183 10.447 -30.332 18.115 c -10.212 8.561 -18.699 18.566 -25.007 30.289 c -6.694 12.439 -10.525 25.73 -10.663 39.955"
+            style="fill:#880000;fill-opacity:1;fill-rule:nonzero;stroke:none"
+            id="path26"/>
+        </g>
+        <g id="g28" transform="translate(189.0308,331.666)">
+          <path d="M 0,0 C 0,0 115.969,112 248.5,98.1" style="fill:#880000;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path30"/>
+        </g>
+      </g>
+    </g>
+  </g>
+</svg>
\ No newline at end of file

From e0a5d94e7d4c5a1d2098bbf50b95bb790e80d25a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Jan 2021 12:15:29 -0500
Subject: [PATCH 1608/2348] test(document): repro #9798

---
 test/document.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index aa6e01f2726..31836103fd5 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9833,4 +9833,21 @@ describe('document', function() {
       assert.equal(fromDb.arr[0].abc, 'ghi');
     });
   });
+
+  it('handles paths named `db` (gh-9798)', function() {
+    const schema = new Schema({
+      db: String
+    });
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield Test.create({ db: 'foo' });
+      doc.db = 'bar';
+      yield doc.save();
+      yield doc.deleteOne();
+
+      const _doc = yield Test.findOne({ db: 'bar' });
+      assert.ok(!_doc);
+    });
+  });
 });

From 1d8feed95fdfbef28c53abe3aa136e1296274e69 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Jan 2021 12:15:41 -0500
Subject: [PATCH 1609/2348] fix(document): handle using `db` as a document path

Fix #9798
---
 lib/model.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index cf8bdfff7fc..7423f25af5f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -479,7 +479,7 @@ Model.prototype.save = function(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return this.db.base._promiseOrCallback(fn, cb => {
+  return this.constructor.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
 
     if (parallelSave) {
@@ -934,7 +934,7 @@ Model.prototype.remove = function remove(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return this.db.base._promiseOrCallback(fn, cb => {
+  return this.constructor.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
     this.$__remove(options, (err, res) => {
       this.$op = null;
@@ -973,7 +973,7 @@ Model.prototype.deleteOne = function deleteOne(options, fn) {
 
   fn = this.constructor.$handleCallbackError(fn);
 
-  return this.db.base._promiseOrCallback(fn, cb => {
+  return this.constructor.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
     this.$__deleteOne(options, cb);
   }, this.constructor.events);

From eeffa096df643917bd045b5b3b8c0d64e817f8e9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Jan 2021 12:37:02 -0500
Subject: [PATCH 1610/2348] fix(index.d.ts): require setting `new: true` or
 `returnOriginal: false` to skip null check with `findOneAndUpdate()`

Fix #9654
---
 index.d.ts                   | 12 +++++++-----
 test/typescript/main.test.js |  2 +-
 test/typescript/queries.ts   |  3 ++-
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 200a08db8e2..4189df6041a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -795,7 +795,7 @@ declare module 'mongoose' {
     findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
@@ -805,11 +805,11 @@ declare module 'mongoose' {
     findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T>;
@@ -1757,6 +1757,8 @@ declare module 'mongoose' {
     }
   }
 
+  type ReturnsNewDoc = { new: true } | { returnOriginal: false };
+
   interface Query<ResultType, DocType extends Document> {
     _mongooseOptions: MongooseQueryOptions;
 
@@ -1879,14 +1881,14 @@ declare module 'mongoose' {
     findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true }, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Specifies a `$geometry` condition */
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index dcd3f2a038c..c3a44258eb5 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -48,7 +48,7 @@ describe('typescript syntax', function() {
   });
 
   it('queries', function() {
-    const errors = runTest('queries.ts');
+    const errors = runTest('queries.ts', { strict: true });
     if (process.env.D && errors.length) {
       console.log(errors);
     }
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index ba391e90813..298ac4e0b8f 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -37,7 +37,8 @@ Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).exec().then((res: ITe
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test2' }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { $set: { name: 'test2' } }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest | null) => console.log(res));
-Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true }).then((res: ITest) => { res.name = 'test4'; });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, new: true }).then((res: ITest) => { res.name = 'test4'; });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, returnOriginal: false }).then((res: ITest) => { res.name = 'test4'; });
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
 

From bcf716adb25413e6ecd32485b5660a981fbe6881 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Jan 2021 12:55:05 -0500
Subject: [PATCH 1611/2348] fix(index.d.ts): correct query type for
 `findOneAndUpdate()` and `findByIdAndUpdate()` with `rawResult = true`

Fix #9803
---
 index.d.ts                 | 4 ++++
 test/typescript/queries.ts | 1 +
 2 files changed, 5 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 4189df6041a..416e256eb64 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -796,6 +796,7 @@ declare module 'mongoose' {
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
@@ -810,6 +811,7 @@ declare module 'mongoose' {
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
     findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T>;
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T>;
@@ -1882,6 +1884,7 @@ declare module 'mongoose' {
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
     findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType>;
     findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
@@ -1889,6 +1892,7 @@ declare module 'mongoose' {
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Specifies a `$geometry` condition */
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 298ac4e0b8f..c195fbb4d2b 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -39,6 +39,7 @@ Test.findOneAndUpdate({ name: 'test' }, { $set: { name: 'test2' } }).then((res:
 Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, new: true }).then((res: ITest) => { res.name = 'test4'; });
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, returnOriginal: false }).then((res: ITest) => { res.name = 'test4'; });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { rawResult: true }).then((res) => { console.log(res.ok); });
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
 

From 8d25712004a7be62e49bcbf7496e5d68799e81e6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Jan 2021 14:26:24 -0500
Subject: [PATCH 1612/2348] fix(index.d.ts): make methods and statics optional
 on schema

Fix #9801
---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 416e256eb64..3581f228547 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1092,7 +1092,7 @@ declare module 'mongoose' {
     method(obj: { [name: string]: (this: DocType, ...args: any[]) => any }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [F in keyof DocType]: DocType[F] } & { [name: string]: (this: DocType, ...args: any[]) => any };
+    methods: { [F in keyof DocType]?: DocType[F] } & { [name: string]: (this: DocType, ...args: any[]) => any };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1151,7 +1151,7 @@ declare module 'mongoose' {
     static(obj: { [name: string]: (this: M, ...args: any[]) => any }): this;
 
     /** Object of currently defined statics on this schema. */
-    statics: { [F in keyof M]: M[F] } & { [name: string]: (this: M, ...args: any[]) => any };
+    statics: { [F in keyof M]?: M[F] } & { [name: string]: (this: M, ...args: any[]) => any };
 
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;

From df05eaa5018e6d99675a6027b328fbb10041621c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 13 Jan 2021 14:44:02 -0500
Subject: [PATCH 1613/2348] fix(index.d.ts): remove non backwards compatible
 methods restriction re: #9801

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3581f228547..52c1132961c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1092,7 +1092,7 @@ declare module 'mongoose' {
     method(obj: { [name: string]: (this: DocType, ...args: any[]) => any }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [F in keyof DocType]?: DocType[F] } & { [name: string]: (this: DocType, ...args: any[]) => any };
+    methods: { [name: string]: (this: DocType, ...args: any[]) => any };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1151,7 +1151,7 @@ declare module 'mongoose' {
     static(obj: { [name: string]: (this: M, ...args: any[]) => any }): this;
 
     /** Object of currently defined statics on this schema. */
-    statics: { [F in keyof M]?: M[F] } & { [name: string]: (this: M, ...args: any[]) => any };
+    statics: { [name: string]: (this: M, ...args: any[]) => any };
 
     /** Creates a virtual type with the given name. */
     virtual(name: string, options?: any): VirtualType;

From 0fcca594f79c242d18f7db431cb9b18ddd769fde Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 14 Jan 2021 15:31:17 -0500
Subject: [PATCH 1614/2348] fix(collection): make sure to call `onOpen()` if
 `autoCreate === false`

Fix #9807
---
 lib/drivers/node-mongodb-native/collection.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index fdb5aae0161..88eac58dd9b 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -54,6 +54,7 @@ NativeCollection.prototype.onOpen = function() {
 
   if (_this.opts.autoCreate === false) {
     _this.collection = _this.conn.db.collection(_this.name);
+    MongooseCollection.prototype.onOpen.call(_this);
     return _this.collection;
   }
 

From c44d521e18d292817a37c9c1623721da52a249f6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 14 Jan 2021 15:38:35 -0500
Subject: [PATCH 1615/2348] chore: release 5.11.12

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f28d0576bb6..0567d6f22c6 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.11.12 / 2021-01-14
+====================
+ * fix(document): handle using `db` as a document path #9798
+ * fix(collection): make sure to call `onOpen()` if `autoCreate === false` #9807
+ * fix(index.d.ts): correct query type for `findOneAndUpdate()` and `findByIdAndUpdate()` with `rawResult = true` #9803
+ * fix(index.d.ts): require setting `new: true` or `returnOriginal: false` to skip null check with `findOneAndUpdate()` #9654
+ * fix(index.d.ts): make methods and statics optional on schema #9801
+ * fix(index.d.ts): remove non backwards compatible methods restriction #9801
+ * docs: removed the extra word on comment doc #9794 [HenriqueLBorges](https://github.com/HenriqueLBorges)
+
 5.11.11 / 2021-01-08
 ====================
  * fix(model): support calling `create()` with `undefined` as first argument and no callback #9765
diff --git a/package.json b/package.json
index 666062bd04b..9fa6760830b 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.11",
+  "version": "5.11.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From ce8d548acb46d52b038cb0c69407f26d70a51ff9 Mon Sep 17 00:00:00 2001
From: Piero Maltese <maltesepiero@gmail.com>
Date: Mon, 18 Jan 2021 11:19:03 +0000
Subject: [PATCH 1616/2348] chore: changed setOptions's 'overwrite' argument to
 optional

I've changed the 'overwrite' argument of the Query.prototype.setOptions function to be consistent with what described in the documentation: https://mongoosejs.com/docs/api.html#query_Query-setOptions
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 52c1132961c..c6bff838310 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2075,7 +2075,7 @@ declare module 'mongoose' {
     set(path: string, value: any): this;
 
     /** Sets query options. Some options only make sense for certain operations. */
-    setOptions(options: QueryOptions, overwrite: boolean): this;
+    setOptions(options: QueryOptions, overwrite?: boolean): this;
 
     /** Sets the query conditions to the provided JSON object. */
     setQuery(val: FilterQuery<DocType> | null): void;

From ec0ef92636d274a299105411292bb02a7e55ed31 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Jan 2021 16:38:59 -0500
Subject: [PATCH 1617/2348] fix(index.d.ts): allow setting `mongoose.Promise`

Fix #9820
---
 index.d.ts                | 2 +-
 test/typescript/global.ts | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c6bff838310..082044ceaff 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -53,7 +53,7 @@ declare module 'mongoose' {
    */
   export type ObjectId = Schema.Types.ObjectId;
 
-  export const Promise: any;
+  export let Promise: any;
   export const PromiseProvider: any;
 
   /** The various Mongoose SchemaTypes. */
diff --git a/test/typescript/global.ts b/test/typescript/global.ts
index 6aae459ddaa..8887190240b 100644
--- a/test/typescript/global.ts
+++ b/test/typescript/global.ts
@@ -11,4 +11,6 @@ m.STATES.connected;
 
 m.connect('mongodb://localhost:27017/test').then(() => {
   console.log('Connected!');
-});
\ No newline at end of file
+});
+
+mongoose.Promise = Promise;
\ No newline at end of file

From f730aff5f265e8d323d3282257cbf40ba9863a6b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Jan 2021 16:46:35 -0500
Subject: [PATCH 1618/2348] fix(index.d.ts): make `Query#options#rawResult`
 take precedence over `new`+`upsert`

Fix #9816
---
 index.d.ts                 | 8 ++++----
 test/typescript/queries.ts | 1 +
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 082044ceaff..aa09890712c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -795,8 +795,8 @@ declare module 'mongoose' {
     findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
@@ -810,8 +810,8 @@ declare module 'mongoose' {
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
 
     geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T>;
@@ -1883,16 +1883,16 @@ declare module 'mongoose' {
     findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
 
     /** Specifies a `$geometry` condition */
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index c195fbb4d2b..699742dd757 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -40,6 +40,7 @@ Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest |
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, new: true }).then((res: ITest) => { res.name = 'test4'; });
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, returnOriginal: false }).then((res: ITest) => { res.name = 'test4'; });
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { rawResult: true }).then((res) => { console.log(res.ok); });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { new: true, upsert: true, rawResult: true }).then((res) => { console.log(res.ok); });
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
 

From 6b65d0d6971a2dae55cf6a31fbd14daea6f7a848 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Jan 2021 16:55:48 -0500
Subject: [PATCH 1619/2348] docs(populate): add note about setting `toObject`
 for populate virtuals

Fix #9822
---
 docs/populate.pug | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index 9ff769a0b54..27b9ec48af8 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -669,16 +669,16 @@ block content
     });
     ```
 
-    Keep in mind that virtuals are _not_ included in `toJSON()` output by default. If you want populate virtuals to show up when using functions
-    that rely on `JSON.stringify()`, like Express'
-    [`res.json()` function](http://expressjs.com/en/4x/api.html#res.json),
+    Keep in mind that virtuals are _not_ included in `toJSON()` and `toObject()` output by default. If you want populate
+    virtuals to show up when using functions that rely on `JSON.stringify()`, like Express'
+    [`res.json()` function](https://masteringjs.io/tutorials/express/json),
     set the `virtuals: true` option on your schema's `toJSON` options.
 
     ```javascript
-    // Set `virtuals: true` so `res.json()` works
-    const BandSchema = new Schema({
-      name: String
-    }, { toJSON: { virtuals: true } });
+    const BandSchema = new Schema({ name: String }, {
+      toJSON: { virtuals: true }, // So `res.json()` and other `JSON.stringify()` functions include virtuals
+      toObject: { virtuals: true } // So `toObject()` output includes virtuals
+    });
     ```
 
     If you're using populate projections, make sure `foreignField` is included

From 3bce4d9d63e7204088e8736c58f4ae3fc55587c2 Mon Sep 17 00:00:00 2001
From: pnutmath <abgawade24@gmail.com>
Date: Tue, 19 Jan 2021 15:52:48 +0530
Subject: [PATCH 1620/2348] TransactionOptions support within transaction
 wrapper

---
 lib/connection.js                     |  7 ++++---
 test/es-next/transactions.test.es6.js | 17 +++++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 65bd6159798..13268769143 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -448,7 +448,7 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
  *
  *       // Throw an error to abort the transaction
  *       throw new Error('Oops!');
- *     }).catch(() => {});
+ *     },{ readPreference: 'primary' }).catch(() => {});
  *
  *     // true, `transaction()` reset the document's state because the
  *     // transaction was aborted.
@@ -456,14 +456,15 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
  *
  * @method transaction
  * @param {Function} fn Function to execute in a transaction
+ * @param {mongodb.TransactionOptions} [options] Optional settings for the transaction
  * @return {Promise<Any>} promise that resolves to the returned value of `fn`
  * @api public
  */
 
-Connection.prototype.transaction = function transaction(fn) {
+Connection.prototype.transaction = function transaction(fn, options) {
   return this.startSession().then(session => {
     session[sessionNewDocuments] = new Map();
-    return session.withTransaction(() => fn(session)).
+    return session.withTransaction(() => fn(session), options).
       then(res => {
         delete session[sessionNewDocuments];
         return res;
diff --git a/test/es-next/transactions.test.es6.js b/test/es-next/transactions.test.es6.js
index 1158361c072..5f28ec7692d 100644
--- a/test/es-next/transactions.test.es6.js
+++ b/test/es-next/transactions.test.es6.js
@@ -419,4 +419,21 @@ describe('transactions', function() {
     const createdDoc = await Test.collection.findOne();
     assert.deepEqual(createdDoc.arr, ['foo']);
   });
+
+  it('can save a new document with an array and read within transaction', async function () {
+    const schema = Schema({ arr: [String] });
+
+    const Test = db.model('new_doc_array', schema);
+
+    await Test.createCollection();
+    const doc = new Test({ arr: ['foo'] });
+    await db.transaction(
+      async (session) => {
+        await doc.save({ session });
+        const testDocs = await Test.collection.find({}).session(session);
+        assert.deepStrictEqual(testDocs.length, 1);
+      },
+      { readPreference: 'primary' }
+    );
+  });
 });

From bcaad30ba3058a44b8541d741f24155bdd00fe4d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 11:46:30 -0500
Subject: [PATCH 1621/2348] test(map): repro #9813

---
 test/types.map.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/types.map.test.js b/test/types.map.test.js
index d5a7772c1e6..a9594b91cb3 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -976,4 +976,29 @@ describe('Map', function() {
       assert.ifError(doc.validateSync());
     });
   });
+
+  it('handles map of arrays (gh-9813)', function() {
+    const BudgetSchema = new mongoose.Schema({
+      budgeted: {
+        type: Map,
+        of: [Number]
+      }
+    });
+
+    const Budget = db.model('Test', BudgetSchema);
+
+    return co(function*() {
+      const _id = yield Budget.create({
+        budgeted: new Map([['2020', [100, 200, 300]]])
+      }).then(doc => doc._id);
+
+      const doc = yield Budget.findById(_id);
+      doc.budgeted.get('2020').set(2, 10);
+      assert.deepEqual(doc.getChanges(), { $set: { 'budgeted.2020.2': 10 } });
+      yield doc.save();
+
+      const res = yield Budget.findOne();
+      assert.deepEqual(res.toObject().budgeted.get('2020'), [100, 200, 10]);
+    });
+  });
 });

From e7eaf6c75c55806d1ebfd358a3b354ed37bd7b18 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 11:46:42 -0500
Subject: [PATCH 1622/2348] fix(map): handle change tracking on map of arrays

Fix #9813
---
 lib/schema/array.js |  4 ++--
 lib/schema/map.js   | 10 ++++++----
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 7351cbef241..e0321c6c7fa 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -340,11 +340,11 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     }
 
     if (!(value && value.isMongooseArray)) {
-      value = MongooseArray(value, this._arrayPath || this.path, doc, this);
+      value = MongooseArray(value, get(options, 'path', null) || this._arrayPath || this.path, doc, this);
     } else if (value && value.isMongooseArray) {
       // We need to create a new array, otherwise change tracking will
       // update the old doc (gh-4449)
-      value = MongooseArray(value, this._arrayPath || this.path, doc, this);
+      value = MongooseArray(value, get(options, 'path', null) || this._arrayPath || this.path, doc, this);
     }
 
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
diff --git a/lib/schema/map.js b/lib/schema/map.js
index 30e3eba8b30..e81dccf4540 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -26,8 +26,10 @@ class Map extends SchemaType {
       return val;
     }
 
+    const path = this.path;
+
     if (init) {
-      const map = new MongooseMap({}, this.path, doc, this.$__schemaType);
+      const map = new MongooseMap({}, path, doc, this.$__schemaType);
 
       if (val instanceof global.Map) {
         for (const key of val.keys()) {
@@ -35,7 +37,7 @@ class Map extends SchemaType {
           if (_val == null) {
             _val = map.$__schemaType._castNullish(_val);
           } else {
-            _val = map.$__schemaType.cast(_val, doc, true);
+            _val = map.$__schemaType.cast(_val, doc, true, null, { path: path + '.' + key });
           }
           map.$init(key, _val);
         }
@@ -45,7 +47,7 @@ class Map extends SchemaType {
           if (_val == null) {
             _val = map.$__schemaType._castNullish(_val);
           } else {
-            _val = map.$__schemaType.cast(_val, doc, true);
+            _val = map.$__schemaType.cast(_val, doc, true, null, { path: path + '.' + key });
           }
           map.$init(key, _val);
         }
@@ -54,7 +56,7 @@ class Map extends SchemaType {
       return map;
     }
 
-    return new MongooseMap(val, this.path, doc, this.$__schemaType);
+    return new MongooseMap(val, path, doc, this.$__schemaType);
   }
 
   clone() {

From 60a32c3b9da7f6e8eef994019c917a85537978fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 11:51:00 -0500
Subject: [PATCH 1623/2348] fix(index.d.ts): add `Aggregate#replaceRoot()`

Fix #9814
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index aa09890712c..76085907763 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2327,6 +2327,9 @@ declare module 'mongoose' {
     /** Appends a new $redact operator to this aggregate pipeline. */
     redact(expression: any, thenExpr: string | any, elseExpr: string | any): this;
 
+    /** Appends a new $replaceRoot operator to this aggregate pipeline. */
+    replaceRoot(newRoot: object | string): this;
+
     /**
      * Helper for [Atlas Text Search](https://docs.atlas.mongodb.com/reference/atlas-search/tutorial/)'s
      * `$search` stage.

From bc2395e059ca7951178caeacc840020e2c2716a4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 11:59:58 -0500
Subject: [PATCH 1624/2348] fix(index.d.ts): make `Model.create()` with a
 spread return a promise of array rather than single doc

Fix #9817
---
 index.d.ts                | 10 +++++-----
 test/typescript/create.ts |  2 +-
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 76085907763..68473960c95 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -630,11 +630,11 @@ declare module 'mongoose' {
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
 
     /** Creates a new document or documents */
-    create<Z = T | DocumentDefinition<T>>(doc: Z): Promise<T>;
-    create<Z = T | DocumentDefinition<T>>(docs: Array<Z>, options?: SaveOptions): Promise<Array<T>>;
-    create<Z = T | DocumentDefinition<T>>(...docs: Array<Z>): Promise<T>;
-    create<Z = T | DocumentDefinition<T>>(doc: Z, callback: (err: CallbackError, doc: T) => void): void;
-    create<Z = T | DocumentDefinition<T>>(docs: Array<Z>, callback: (err: CallbackError, docs: Array<T>) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: T) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: T[]) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
index 98cfa653003..c20f56cc308 100644
--- a/test/typescript/create.ts
+++ b/test/typescript/create.ts
@@ -13,7 +13,7 @@ Test.create({ _id: '0'.repeat(24), name: 'test' }).then((doc: ITest) => console.
 
 Test.create([{ name: 'test' }], { validateBeforeSave: false }).then((docs: ITest[]) => console.log(docs[0].name));
 
-Test.create({ name: 'test' }, { name: 'test2' }).then((doc: ITest) => console.log(doc.name));
+Test.create({ name: 'test' }, { name: 'test2' }).then((docs: ITest[]) => console.log(docs[0].name));
 
 Test.insertMany({ name: 'test' }).then((doc: ITest) => console.log(doc.name));
 Test.insertMany([{ name: 'test' }], { session: null }).then((docs: ITest[]) => console.log(docs[0].name));

From c324ed113331848b125014826e3b1694c0057116 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 12:12:57 -0500
Subject: [PATCH 1625/2348] fix(index.d.ts): use SchemaDefinitionProperty
 generic for SchemaTypeOptions if specified

Fix #9815
---
 index.d.ts | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 68473960c95..36a74e37ccc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1163,7 +1163,15 @@ declare module 'mongoose' {
     virtualpath(name: string): VirtualType | null;
   }
 
-  type SchemaDefinitionProperty<T = undefined> = SchemaTypeOptions<any> | Function | string | Schema | Schema[] | Array<SchemaTypeOptions<any>> | Function[] | SchemaDefinition<T> | SchemaDefinition<T>[];
+  type SchemaDefinitionProperty<T = undefined> = SchemaTypeOptions<T extends undefined ? any : T> |
+    Function |
+    string |
+    Schema |
+    Schema[] |
+    SchemaTypeOptions<T extends undefined ? any : T>[] |
+    Function[] |
+    SchemaDefinition<T> |
+    SchemaDefinition<T>[];
 
   type SchemaDefinition<T = undefined> = T extends undefined
     ? { [path: string]: SchemaDefinitionProperty; }

From 5184d672743817a1ede21dbaf0f0df1c875a5fff Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 13:45:43 -0500
Subject: [PATCH 1626/2348] docs: add `client` property to docs

---
 lib/connection.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/connection.js b/lib/connection.js
index 65bd6159798..2dd86f9c7d5 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -361,6 +361,18 @@ Object.defineProperty(Connection.prototype, 'pass', {
 
 Connection.prototype.db;
 
+/**
+ * The MongoClient instance this connection uses to talk to MongoDB. Mongoose automatically sets this property
+ * when the connection is opened.
+ *
+ * @property client
+ * @memberOf Connection
+ * @instance
+ * @api public
+ */
+
+Connection.prototype.client;
+
 /**
  * A hash of the global options that are associated with this connection
  *

From 66430208ee7dfacd42e1df720296b7dc57bb9c1d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Jan 2021 14:20:30 -0500
Subject: [PATCH 1627/2348] docs: add links to then() and catch() tutorials

---
 lib/query.js               |  4 ++++
 test/docs/promises.test.js | 10 +++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index ce49c4cdb14..b115e6f17f7 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4440,6 +4440,8 @@ function _wrapThunkCallback(query, cb) {
  * Executes the query returning a `Promise` which will be
  * resolved with either the doc(s) or rejected with the error.
  *
+ * More about [`then()` in JavaScript](https://masteringjs.io/tutorials/fundamentals/then).
+ *
  * @param {Function} [resolve]
  * @param {Function} [reject]
  * @return {Promise}
@@ -4455,6 +4457,8 @@ Query.prototype.then = function(resolve, reject) {
  * resolved with either the doc(s) or rejected with the error.
  * Like `.then()`, but only takes a rejection handler.
  *
+ * More about [Promise `catch()` in JavaScript](https://masteringjs.io/tutorials/fundamentals/catch).
+ *
  * @param {Function} [reject]
  * @return {Promise}
  * @api public
diff --git a/test/docs/promises.test.js b/test/docs/promises.test.js
index 6a76d3691cf..ec7b6d1da63 100644
--- a/test/docs/promises.test.js
+++ b/test/docs/promises.test.js
@@ -24,7 +24,7 @@ describe('promises docs', function() {
   });
 
   /**
-   * Mongoose async operations, like `.save()` and queries, return thenables.
+   * Mongoose async operations, like `.save()` and queries, return [thenables](https://masteringjs.io/tutorials/fundamentals/thenable).
    * This means that you can do things like `MyModel.findOne({}).then()` and
    * `await MyModel.findOne({}).exec()` if you're using
    * [async/await](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html).
@@ -50,9 +50,9 @@ describe('promises docs', function() {
   });
 
   /**
-   * [Mongoose queries](http://mongoosejs.com/docs/queries.html) are **not** promises. They have a `.then()`
-   * function for [co](https://www.npmjs.com/package/co) and async/await as
-   * a convenience. If you need
+   * [Mongoose queries](http://mongoosejs.com/docs/queries.html) are **not** promises. They have a
+   * [`.then()` function](https://masteringjs.io/tutorials/fundamentals/then) for [co](https://www.npmjs.com/package/co)
+   * and async/await as a convenience. If you need
    * a fully-fledged promise, use the `.exec()` function.
    */
   it('Queries are not promises', function(done) {
@@ -86,7 +86,7 @@ describe('promises docs', function() {
   });
 
   /**
-   * Although queries are not promises, queries are [thenables](https://promisesaplus.com/#terminology).
+   * Although queries are not promises, queries are [thenables](https://masteringjs.io/tutorials/fundamentals/thenable).
    * That means they have a `.then()` function, so you can use queries as promises with either
    * promise chaining or [async await](https://asyncawait.net)
    */

From 9c3a2eb2b808d798633858985522fd4bdca5587a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 19 Jan 2021 18:08:19 -0500
Subject: [PATCH 1628/2348] Ignore this

---
 lib/document.js        |  3 ++-
 lib/model.js           | 10 +++++++---
 lib/schema/map.js      |  1 -
 lib/types/map.js       |  1 -
 test/types.map.test.js | 27 +++++++++++++++++++++++++++
 5 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4b0de80070c..221a5559c6c 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -4135,8 +4135,9 @@ Document.prototype.$__fullPath = function(path) {
 
 Document.prototype.getChanges = function() {
   const delta = this.$__delta();
-
+  console.log('Delta', delta);
   const changes = delta ? delta[1] : {};
+  console.log('Yo', changes);
   return changes;
 };
 
diff --git a/lib/model.js b/lib/model.js
index 7423f25af5f..4c1a3e79bc3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -538,7 +538,8 @@ function operand(self, where, delta, data, val, op) {
   op || (op = '$set');
   if (!delta[op]) delta[op] = {};
   delta[op][data.path] = val;
-
+  console.log('Breaks both times', op);
+  console.log('deltaop', delta);
   // disabled versioning?
   if (self.schema.options.versionKey === false) return;
 
@@ -579,7 +580,7 @@ function operand(self, where, delta, data, val, op) {
   } else if (Array.isArray(val)) {
     // $set an array
     increment.call(self);
-  } else if (/\.\d+\.|\.\d+$/.test(data.path)) {
+  } else if (/\.\d+\.|\.\d+$/.test(data.path) || op === '$set' || op === '$unset') {
     // now handling $set, $unset
     // subpath of array
     self.$__.version = VERSION_WHERE;
@@ -686,6 +687,8 @@ Model.prototype.$__delta = function() {
   }
 
   for (; d < len; ++d) {
+    console.log('In a for loop');
+    console.log(dirty[0]);
     const data = dirty[d];
     let value = data.value;
 
@@ -719,6 +722,7 @@ Model.prototype.$__delta = function() {
     if (divergent.length) continue;
 
     if (value === undefined) {
+      console.log('1st call');
       operand(this, where, delta, data, 1, '$unset');
     } else if (value === null) {
       operand(this, where, delta, data, null);
@@ -737,6 +741,7 @@ Model.prototype.$__delta = function() {
         getters: false,
         _isNested: true
       });
+      console.log('2nd call');
       operand(this, where, delta, data, value);
     }
   }
@@ -748,7 +753,6 @@ Model.prototype.$__delta = function() {
   if (this.$__.version) {
     this.$__version(where, delta);
   }
-
   return [where, delta];
 };
 
diff --git a/lib/schema/map.js b/lib/schema/map.js
index 30e3eba8b30..8c57b1b0315 100644
--- a/lib/schema/map.js
+++ b/lib/schema/map.js
@@ -53,7 +53,6 @@ class Map extends SchemaType {
 
       return map;
     }
-
     return new MongooseMap(val, this.path, doc, this.$__schemaType);
   }
 
diff --git a/lib/types/map.js b/lib/types/map.js
index f50402e1341..2485864c4f6 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -19,7 +19,6 @@ class MongooseMap extends Map {
       v = Object.keys(v).reduce((arr, key) => arr.concat([[key, v[key]]]), []);
     }
     super(v);
-
     this.$__parent = doc != null && doc.$__ != null ? doc : null;
     this.$__path = path;
     this.$__schemaType = schemaType == null ? new Mixed(path) : schemaType;
diff --git a/test/types.map.test.js b/test/types.map.test.js
index d5a7772c1e6..a524693358d 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -976,4 +976,31 @@ describe('Map', function() {
       assert.ifError(doc.validateSync());
     });
   });
+  it('tracks changes correctly (gh-9811)', function() {
+    const SubSchema = Schema({
+      myValue: {
+        type: String
+      }
+    }, { _id: false });
+    const schema = Schema({
+      myMap: {
+        type: Map,
+        of: {
+          type: SubSchema
+        }
+        // required: true
+      }
+    }, { minimize: false, collection: 'test' });
+    const Model = db.model('Test', schema);
+    return co(function*() {
+      const doc = yield Model.create({
+        myMap: new Map()
+      });
+      doc.myMap.set('abc', { myValue: 'some value' });
+      const changes = doc.getChanges();
+      // console.log(changes);
+      assert.ok(!changes.$unset);
+      assert.deepEqual(changes, { $set: { 'myMap.abc': 'some value' } });
+    });
+  });
 });

From 0f0c32b4a499a6cdae7ca288f53f1bdb8e66b67e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 20 Jan 2021 11:35:05 -0500
Subject: [PATCH 1629/2348] chore: release 5.11.13

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 0567d6f22c6..e3f40f5caf3 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.11.13 / 2021-01-20
+====================
+ * fix(map): handle change tracking on map of arrays #9813
+ * fix(connection): allow passing options to `Connection#transaction()` #9834 [pnutmath](https://github.com/pnutmath)
+ * fix(index.d.ts): make `Query#options#rawResult` take precedence over `new`+`upsert` #9816
+ * fix(index.d.ts): changed setOptions's 'overwrite' argument to optional #9824 [pierissimo](https://github.com/pierissimo)
+ * fix(index.d.ts): allow setting `mongoose.Promise` #9820
+ * fix(index.d.ts): add `Aggregate#replaceRoot()` #9814
+ * fix(index.d.ts): make `Model.create()` with a spread return a promise of array rather than single doc #9817
+ * fix(index.d.ts): use SchemaDefinitionProperty generic for SchemaTypeOptions if specified #9815
+ * docs(populate): add note about setting `toObject` for populate virtuals #9822
+
 5.11.12 / 2021-01-14
 ====================
  * fix(document): handle using `db` as a document path #9798
diff --git a/package.json b/package.json
index 9fa6760830b..614c4cc209f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.12",
+  "version": "5.11.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 64f929a0d06267f53fe0bfe1e32f1f91de7c3548 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 20 Jan 2021 17:26:57 -0500
Subject: [PATCH 1630/2348] fix: no more $unset

---
 lib/document.js                | 2 --
 lib/model.js                   | 5 -----
 lib/schema/SingleNestedPath.js | 8 ++++----
 lib/types/map.js               | 2 +-
 lib/types/subdocument.js       | 4 +++-
 test/types.map.test.js         | 3 +--
 6 files changed, 9 insertions(+), 15 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 221a5559c6c..4cf7cd96731 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -4135,9 +4135,7 @@ Document.prototype.$__fullPath = function(path) {
 
 Document.prototype.getChanges = function() {
   const delta = this.$__delta();
-  console.log('Delta', delta);
   const changes = delta ? delta[1] : {};
-  console.log('Yo', changes);
   return changes;
 };
 
diff --git a/lib/model.js b/lib/model.js
index 4c1a3e79bc3..87b06b48350 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -538,8 +538,6 @@ function operand(self, where, delta, data, val, op) {
   op || (op = '$set');
   if (!delta[op]) delta[op] = {};
   delta[op][data.path] = val;
-  console.log('Breaks both times', op);
-  console.log('deltaop', delta);
   // disabled versioning?
   if (self.schema.options.versionKey === false) return;
 
@@ -687,8 +685,6 @@ Model.prototype.$__delta = function() {
   }
 
   for (; d < len; ++d) {
-    console.log('In a for loop');
-    console.log(dirty[0]);
     const data = dirty[d];
     let value = data.value;
 
@@ -741,7 +737,6 @@ Model.prototype.$__delta = function() {
         getters: false,
         _isNested: true
       });
-      console.log('2nd call');
       operand(this, where, delta, data, value);
     }
   }
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index 5024728046a..bbbf523addd 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -147,7 +147,7 @@ SingleNestedPath.prototype.$conditionalHandlers.$exists = $exists;
  * @api private
  */
 
-SingleNestedPath.prototype.cast = function(val, doc, init, priorVal) {
+SingleNestedPath.prototype.cast = function(val, doc, init, priorVal, options) {
   if (val && val.$isSingleNested && val.parent === doc) {
     return val;
   }
@@ -169,16 +169,16 @@ SingleNestedPath.prototype.cast = function(val, doc, init, priorVal) {
     }
     return obj;
   }, {});
-
+  options = Object.assign({}, options, { priorDoc: priorVal });
   if (init) {
     subdoc = new Constructor(void 0, selected, doc);
     subdoc.init(val);
   } else {
     if (Object.keys(val).length === 0) {
-      return new Constructor({}, selected, doc, undefined, { priorDoc: priorVal });
+      return new Constructor({}, selected, doc, undefined, options);
     }
 
-    return new Constructor(val, selected, doc, undefined, { priorDoc: priorVal });
+    return new Constructor(val, selected, doc, undefined, options);
   }
 
   return subdoc;
diff --git a/lib/types/map.js b/lib/types/map.js
index 2485864c4f6..7ce6ad1f313 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -76,7 +76,7 @@ class MongooseMap extends Map {
     } else {
       try {
         value = this.$__schemaType.
-          applySetters(value, this.$__parent, false, this.get(key));
+          applySetters(value, this.$__parent, false, this.get(key), { path: fullPath});
       } catch (error) {
         if (this.$__parent != null && this.$__parent.$__ != null) {
           this.$__parent.invalidate(fullPath, error);
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index e2693054ab7..bc37342467c 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -18,7 +18,9 @@ module.exports = Subdocument;
 
 function Subdocument(value, fields, parent, skipId, options) {
   this.$isSingleNested = true;
-
+  if (options != null && options.path != null) {
+    this.$basePath = options.path;
+  }
   const hasPriorDoc = options != null && options.priorDoc;
   let initedPaths = null;
   if (hasPriorDoc) {
diff --git a/test/types.map.test.js b/test/types.map.test.js
index a524693358d..771035fb8be 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -998,9 +998,8 @@ describe('Map', function() {
       });
       doc.myMap.set('abc', { myValue: 'some value' });
       const changes = doc.getChanges();
-      // console.log(changes);
       assert.ok(!changes.$unset);
-      assert.deepEqual(changes, { $set: { 'myMap.abc': 'some value' } });
+      assert.deepEqual(changes, { $set: { 'myMap.abc': { myValue: 'some value' } } });
     });
   });
 });

From e67e2414d9fc5d99b29cd161f86c78e9c2c8a0a4 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 20 Jan 2021 17:35:40 -0500
Subject: [PATCH 1631/2348] made requested changes

---
 lib/model.js     | 3 +--
 lib/types/map.js | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 87b06b48350..d7df3360d0e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -578,7 +578,7 @@ function operand(self, where, delta, data, val, op) {
   } else if (Array.isArray(val)) {
     // $set an array
     increment.call(self);
-  } else if (/\.\d+\.|\.\d+$/.test(data.path) || op === '$set' || op === '$unset') {
+  } else if (/\.\d+\.|\.\d+$/.test(data.path)) {
     // now handling $set, $unset
     // subpath of array
     self.$__.version = VERSION_WHERE;
@@ -718,7 +718,6 @@ Model.prototype.$__delta = function() {
     if (divergent.length) continue;
 
     if (value === undefined) {
-      console.log('1st call');
       operand(this, where, delta, data, 1, '$unset');
     } else if (value === null) {
       operand(this, where, delta, data, null);
diff --git a/lib/types/map.js b/lib/types/map.js
index 7ce6ad1f313..b992259870b 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -76,7 +76,7 @@ class MongooseMap extends Map {
     } else {
       try {
         value = this.$__schemaType.
-          applySetters(value, this.$__parent, false, this.get(key), { path: fullPath});
+          applySetters(value, this.$__parent, false, this.get(key), { path: fullPath });
       } catch (error) {
         if (this.$__parent != null && this.$__parent.$__ != null) {
           this.$__parent.invalidate(fullPath, error);

From 0d942175adb5447ae5f04675368c1e123fc8e731 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 20 Jan 2021 17:48:29 -0500
Subject: [PATCH 1632/2348] fix: changed dependency

---
 lib/document.js   | 2 +-
 lib/schematype.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4b0de80070c..0761ac76791 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2111,7 +2111,7 @@ Document.prototype.isSelected = function isSelected(path) {
   return !inclusive;
 };
 
-Document.prototype[documentIsSelected] = Document.prototype.isSelected;
+Document.prototype.$__isSelected = Document.prototype.isSelected;
 
 /**
  * Checks if `path` was explicitly selected. If no projection, always returns
diff --git a/lib/schematype.js b/lib/schematype.js
index f6b7b1e0651..7001393bd5a 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -953,7 +953,7 @@ SchemaType.prototype.required = function(required, message) {
     const cachedRequired = get(this, '$__.cachedRequired');
 
     // no validation when this path wasn't selected in the query.
-    if (cachedRequired != null && !this[documentIsSelected](_this.path) && !this[documentIsModified](_this.path)) {
+    if (cachedRequired != null && !this.$__isSelected(_this.path) && !this[documentIsModified](_this.path)) {
       return true;
     }
 

From c6ca5b5b6cb5c370f460630880c9010420b2a47e Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 20 Jan 2021 17:50:35 -0500
Subject: [PATCH 1633/2348] additional fixes

---
 lib/document.js   | 1 -
 lib/schematype.js | 2 --
 2 files changed, 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0761ac76791..ae6924adbb8 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -41,7 +41,6 @@ const isMongooseObject = utils.isMongooseObject;
 const arrayAtomicsBackupSymbol = Symbol('mongoose.Array#atomicsBackup');
 const arrayAtomicsSymbol = require('./helpers/symbols').arrayAtomicsSymbol;
 const documentArrayParent = require('./helpers/symbols').documentArrayParent;
-const documentIsSelected = require('./helpers/symbols').documentIsSelected;
 const documentIsModified = require('./helpers/symbols').documentIsModified;
 const documentModifiedPaths = require('./helpers/symbols').documentModifiedPaths;
 const documentSchemaSymbol = require('./helpers/symbols').documentSchemaSymbol;
diff --git a/lib/schematype.js b/lib/schematype.js
index 7001393bd5a..fc5fba69c7a 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -15,8 +15,6 @@ const schemaTypeSymbol = require('./helpers/symbols').schemaTypeSymbol;
 const util = require('util');
 const utils = require('./utils');
 const validatorErrorSymbol = require('./helpers/symbols').validatorErrorSymbol;
-
-const documentIsSelected = require('./helpers/symbols').documentIsSelected;
 const documentIsModified = require('./helpers/symbols').documentIsModified;
 
 const CastError = MongooseError.CastError;

From d15988593fcd39adfbf6d1881ece2e07088c0ea5 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 10:58:38 -0500
Subject: [PATCH 1634/2348] fix: replaced this.schema with this.$__schema where
 appropriate

---
 lib/browserDocument.js                    |  4 +-
 lib/document.js                           | 86 +++++++++++------------
 lib/helpers/timestamps/setupTimestamps.js |  2 +-
 lib/model.js                              | 38 +++++-----
 lib/plugins/removeSubdocs.js              |  2 +-
 lib/plugins/saveSubdocs.js                |  4 +-
 lib/plugins/sharding.js                   |  2 +-
 lib/plugins/trackTransaction.js           |  4 +-
 lib/plugins/validateBeforeSave.js         |  4 +-
 lib/query.js                              |  4 +-
 lib/schema/SingleNestedPath.js            |  4 +-
 lib/schema/documentarray.js               |  6 +-
 lib/types/subdocument.js                  |  6 +-
 test/document.unit.test.js                |  4 +-
 test/schema.test.js                       | 46 ++++++------
 15 files changed, 108 insertions(+), 108 deletions(-)

diff --git a/lib/browserDocument.js b/lib/browserDocument.js
index a44f3077e01..259ac66210f 100644
--- a/lib/browserDocument.js
+++ b/lib/browserDocument.js
@@ -35,10 +35,10 @@ function Document(obj, schema, fields, skipId, skipInit) {
   }
 
   // When creating EmbeddedDocument, it already has the schema and he doesn't need the _id
-  schema = this.schema || schema;
+  schema = this.$__schema || schema;
 
   // Generate ObjectId if it is missing, but it requires a scheme
-  if (!this.schema && schema.options._id) {
+  if (!this.$__schema && schema.options._id) {
     obj = obj || {};
 
     if (obj._id === undefined) {
diff --git a/lib/document.js b/lib/document.js
index cb5317c72f8..36e880e793d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -78,7 +78,7 @@ function Document(obj, fields, skipId, options) {
   options.defaults = defaults;
 
   // Support `browserDocument.js` syntax
-  if (this.schema == null) {
+  if (this.$__schema == null) {
     const _schema = utils.isObject(fields) && !fields.instanceOfSchema ?
       new Schema(fields) :
       fields;
@@ -100,7 +100,7 @@ function Document(obj, fields, skipId, options) {
     throw new ObjectParameterError(obj, 'obj', 'Document');
   }
 
-  const schema = this.schema;
+  const schema = this.$__schema;
 
   if (typeof fields === 'boolean' || fields === 'throw') {
     this.$__.strictMode = fields;
@@ -213,7 +213,7 @@ for (const i in EventEmitter.prototype) {
  * @instance
  */
 
-Document.prototype.schema;
+Document.prototype.$__schema;
 
 /**
  * Empty object that you can use for storing properties on the document. This
@@ -459,7 +459,7 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
 Document.prototype.$__buildDoc = function(obj, fields, skipId, exclude, hasIncludedChildren) {
   const doc = {};
 
-  const paths = Object.keys(this.schema.paths).
+  const paths = Object.keys(this.$__schema.paths).
     // Don't build up any paths that are underneath a map, we don't know
     // what the keys will be
     filter(p => !p.includes('$*'));
@@ -872,10 +872,10 @@ Document.prototype.overwrite = function overwrite(obj) {
       continue;
     }
     // Explicitly skip version key
-    if (this.schema.options.versionKey && key === this.schema.options.versionKey) {
+    if (this.$__schema.options.versionKey && key === this.$__schema.options.versionKey) {
       continue;
     }
-    if (this.schema.options.discriminatorKey && key === this.schema.options.discriminatorKey) {
+    if (this.$__schema.options.discriminatorKey && key === this.$__schema.options.discriminatorKey) {
       continue;
     }
     this.$set(key, obj[key]);
@@ -921,7 +921,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
   if (adhoc) {
     adhocs = this.$__.adhocPaths || (this.$__.adhocPaths = {});
-    adhocs[path] = this.schema.interpretAsType(path, type, this.schema.options);
+    adhocs[path] = this.$__schema.interpretAsType(path, type, this.$__schema.options);
   }
 
   if (path == null) {
@@ -957,7 +957,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
     for (let i = 0; i < len; ++i) {
       key = keys[i];
       const pathName = prefix + key;
-      pathtype = this.schema.pathType(pathName);
+      pathtype = this.$__schema.pathType(pathName);
 
       // On initial set, delete any nested keys if we're going to overwrite
       // them to ensure we keep the user's key order.
@@ -980,9 +980,9 @@ Document.prototype.$set = function $set(path, val, type, options) {
                             pathtype !== 'real' &&
                             pathtype !== 'adhocOrUndefined' &&
                             !(this.$__path(pathName) instanceof MixedSchema) &&
-                            !(this.schema.paths[pathName] &&
-                            this.schema.paths[pathName].options &&
-                            this.schema.paths[pathName].options.ref);
+                            !(this.$__schema.paths[pathName] &&
+                            this.$__schema.paths[pathName].options &&
+                            this.$__schema.paths[pathName].options.ref);
 
       if (someCondition) {
         this.$__.$setCalled.add(prefix + key);
@@ -1001,8 +1001,8 @@ Document.prototype.$set = function $set(path, val, type, options) {
         if (pathtype === 'real' || pathtype === 'virtual') {
           // Check for setting single embedded schema to document (gh-3535)
           let p = path[key];
-          if (this.schema.paths[pathName] &&
-              this.schema.paths[pathName].$isSingleNested &&
+          if (this.$__schema.paths[pathName] &&
+              this.$__schema.paths[pathName].$isSingleNested &&
               path[key] instanceof Document) {
             p = p.toObject({ virtuals: false, transform: false });
           }
@@ -1027,7 +1027,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
     this.$__.$setCalled.add(path);
   }
 
-  let pathType = this.schema.pathType(path);
+  let pathType = this.$__schema.pathType(path);
   if (pathType === 'adhocOrUndefined') {
     pathType = getEmbeddedDiscriminatorPath(this, path, { typeOnly: true });
   }
@@ -1078,8 +1078,8 @@ Document.prototype.$set = function $set(path, val, type, options) {
   const parts = path.indexOf('.') === -1 ? [path] : path.split('.');
 
   // Might need to change path for top-level alias
-  if (typeof this.schema.aliases[parts[0]] == 'string') {
-    parts[0] = this.schema.aliases[parts[0]];
+  if (typeof this.$__schema.aliases[parts[0]] == 'string') {
+    parts[0] = this.$__schema.aliases[parts[0]];
   }
 
   if (pathType === 'adhocOrUndefined' && strict) {
@@ -1090,12 +1090,12 @@ Document.prototype.$set = function $set(path, val, type, options) {
       const subpath = parts.slice(0, i + 1).join('.');
 
       // If path is underneath a virtual, bypass everything and just set it.
-      if (i + 1 < parts.length && this.schema.pathType(subpath) === 'virtual') {
+      if (i + 1 < parts.length && this.$__schema.pathType(subpath) === 'virtual') {
         mpath.set(path, val, this);
         return this;
       }
 
-      schema = this.schema.path(subpath);
+      schema = this.$__schema.path(subpath);
       if (schema == null) {
         continue;
       }
@@ -1119,7 +1119,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
       return this;
     }
   } else if (pathType === 'virtual') {
-    schema = this.schema.virtualpath(path);
+    schema = this.$__schema.virtualpath(path);
     schema.applySetters(val, this);
     return this;
   } else {
@@ -1239,10 +1239,10 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
     let popOpts;
     if (schema.options &&
-        Array.isArray(schema.options[this.schema.options.typeKey]) &&
-        schema.options[this.schema.options.typeKey].length &&
-        schema.options[this.schema.options.typeKey][0].ref &&
-        _isManuallyPopulatedArray(val, schema.options[this.schema.options.typeKey][0].ref)) {
+        Array.isArray(schema.options[this.$__schema.options.typeKey]) &&
+        schema.options[this.$__schema.options.typeKey].length &&
+        schema.options[this.$__schema.options.typeKey][0].ref &&
+        _isManuallyPopulatedArray(val, schema.options[this.$__schema.options.typeKey][0].ref)) {
       if (this.ownerDocument) {
         popOpts = { [populateModelSymbol]: val[0].constructor };
         this.ownerDocument().populated(this.$__fullPath(path),
@@ -1257,7 +1257,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
       didPopulate = true;
     }
 
-    if (this.schema.singleNestedPaths[path] == null) {
+    if (this.$__schema.singleNestedPaths[path] == null) {
       // If this path is underneath a single nested schema, we'll call the setter
       // later in `$__set()` because we don't take `_doc` when we iterate through
       // a single nested doc. That's to make sure we get the correct context.
@@ -1416,7 +1416,7 @@ Document.prototype.$__shouldModify = function(pathToMark, path, constructing, pa
   // Re: the note about gh-7196, `val` is the raw value without casting or
   // setters if the full path is under a single nested subdoc because we don't
   // want to double run setters. So don't set it as modified. See gh-7264.
-  if (this.schema.singleNestedPaths[path] != null) {
+  if (this.$__schema.singleNestedPaths[path] != null) {
     return false;
   }
 
@@ -1579,15 +1579,15 @@ Document.prototype.get = function(path, type, options) {
   let adhoc;
   options = options || {};
   if (type) {
-    adhoc = this.schema.interpretAsType(path, type, this.schema.options);
+    adhoc = this.$__schema.interpretAsType(path, type, this.$__schema.options);
   }
 
   let schema = this.$__path(path);
   if (schema == null) {
-    schema = this.schema.virtualpath(path);
+    schema = this.$__schema.virtualpath(path);
   }
   if (schema instanceof MixedSchema) {
-    const virtual = this.schema.virtualpath(path);
+    const virtual = this.$__schema.virtualpath(path);
     if (virtual != null) {
       schema = virtual;
     }
@@ -1600,8 +1600,8 @@ Document.prototype.get = function(path, type, options) {
   }
 
   // Might need to change path for top-level alias
-  if (typeof this.schema.aliases[pieces[0]] == 'string') {
-    pieces[0] = this.schema.aliases[pieces[0]];
+  if (typeof this.$__schema.aliases[pieces[0]] == 'string') {
+    pieces[0] = this.$__schema.aliases[pieces[0]];
   }
 
   for (let i = 0, l = pieces.length; i < l; i++) {
@@ -1626,7 +1626,7 @@ Document.prototype.get = function(path, type, options) {
 
   if (schema != null && options.getters !== false) {
     obj = schema.applyGetters(obj, this);
-  } else if (this.schema.nested[path] && options.virtuals) {
+  } else if (this.$__schema.nested[path] && options.virtuals) {
     // Might need to apply virtuals if this is a nested path
     return applyVirtuals(this, utils.clone(obj) || {}, { path: path });
   }
@@ -1657,7 +1657,7 @@ Document.prototype.$__path = function(path) {
   if (adhocType) {
     return adhocType;
   }
-  return this.schema.path(path);
+  return this.$__schema.path(path);
 };
 
 /**
@@ -2389,7 +2389,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   if (hasValidateModifiedOnlyOption) {
     shouldValidateModifiedOnly = !!options.validateModifiedOnly;
   } else {
-    shouldValidateModifiedOnly = this.schema.options.validateModifiedOnly;
+    shouldValidateModifiedOnly = this.$__schema.options.validateModifiedOnly;
   }
 
   const _this = this;
@@ -2443,7 +2443,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     return process.nextTick(function() {
       const error = _complete();
       if (error) {
-        return _this.schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
           callback(error);
         });
       }
@@ -2457,7 +2457,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   const complete = function() {
     const error = _complete();
     if (error) {
-      return _this.schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
+      return _this.$__schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
         callback(error);
       });
     }
@@ -2473,7 +2473,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     total++;
 
     process.nextTick(function() {
-      const schemaType = _this.schema.path(path);
+      const schemaType = _this.$__schema.path(path);
 
       if (!schemaType) {
         return --total || complete();
@@ -2589,7 +2589,7 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
   if (hasValidateModifiedOnlyOption) {
     shouldValidateModifiedOnly = !!options.validateModifiedOnly;
   } else {
-    shouldValidateModifiedOnly = this.schema.options.validateModifiedOnly;
+    shouldValidateModifiedOnly = this.$__schema.options.validateModifiedOnly;
   }
 
   if (typeof pathsToValidate === 'string') {
@@ -2616,7 +2616,7 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
 
     validating[path] = true;
 
-    const p = _this.schema.path(path);
+    const p = _this.$__schema.path(path);
     if (!p) {
       return;
     }
@@ -2915,7 +2915,7 @@ Document.prototype.$__reset = function reset() {
   this.$__.validationError = undefined;
   this.errors = undefined;
   _this = this;
-  this.schema.requiredPaths().forEach(function(path) {
+  this.$__schema.requiredPaths().forEach(function(path) {
     _this.$__.activePaths.require(path);
   });
 
@@ -3037,7 +3037,7 @@ Document.prototype.$__setSchema = function(schema) {
     schema.virtuals[key]._applyDefaultGetters();
   }
 
-  this.schema = schema;
+  this.$__schema = schema;
   this[documentSchemaSymbol] = schema;
 };
 
@@ -3257,15 +3257,15 @@ Document.prototype.$toObject = function(options, json) {
     applyVirtuals(this, ret, gettersOptions, options);
   }
 
-  if (options.versionKey === false && this.schema.options.versionKey) {
-    delete ret[this.schema.options.versionKey];
+  if (options.versionKey === false && this.$__schema.options.versionKey) {
+    delete ret[this.$__schema.options.versionKey];
   }
 
   let transform = options.transform;
 
   // In the case where a subdocument has its own transform function, we need to
   // check and see if the parent has a transform (options.transform) and if the
-  // child schema has a transform (this.schema.options.toObject) In this case,
+  // child schema has a transform (this.$__schema.options.toObject) In this case,
   // we need to adjust options.transform to be the child schema's transform and
   // not the parent schema's
   if (transform) {
diff --git a/lib/helpers/timestamps/setupTimestamps.js b/lib/helpers/timestamps/setupTimestamps.js
index 752a565738c..146334cabb9 100644
--- a/lib/helpers/timestamps/setupTimestamps.js
+++ b/lib/helpers/timestamps/setupTimestamps.js
@@ -97,7 +97,7 @@ module.exports = function setupTimestamps(schema, timestamps) {
       currentTime() :
       this.model.base.now();
     applyTimestampsToUpdate(now, createdAt, updatedAt, this.getUpdate(),
-      this.options, this.schema);
+      this.options, this.$__schema);
     applyTimestampsToChildren(now, this.getUpdate(), this.model.schema);
     next();
   }
diff --git a/lib/model.js b/lib/model.js
index d7df3360d0e..77bbf37fcc2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -231,7 +231,7 @@ Model.prototype.$__handleSave = function(options, callback) {
   if ('safe' in options) {
     _handleSafe(options);
   }
-  applyWriteConcern(this.schema, options);
+  applyWriteConcern(this.$__schema, options);
   if ('w' in options) {
     saveOptions.w = options.w;
   }
@@ -346,7 +346,7 @@ Model.prototype.$__handleSave = function(options, callback) {
 
 Model.prototype.$__save = function(options, callback) {
   this.$__handleSave(options, (error, result) => {
-    const hooks = this.schema.s.hooks;
+    const hooks = this.$__schema.s.hooks;
     if (error) {
       return hooks.execPost('save:error', this, [this], { error: error }, (error) => {
         callback(error, this);
@@ -374,7 +374,7 @@ Model.prototype.$__save = function(options, callback) {
         const doIncrement = VERSION_INC === (VERSION_INC & this.$__.version);
         this.$__.version = undefined;
 
-        const key = this.schema.options.versionKey;
+        const key = this.$__schema.options.versionKey;
         const version = this.$__getValue(key) || 0;
 
         if (numAffected <= 0) {
@@ -809,7 +809,7 @@ function checkDivergentArray(doc, path, array) {
  */
 
 Model.prototype.$__version = function(where, delta) {
-  const key = this.schema.options.versionKey;
+  const key = this.$__schema.options.versionKey;
 
   if (where === true) {
     // this is an insert
@@ -1223,7 +1223,7 @@ for (const i in EventEmitter.prototype) {
 Model.init = function init(callback) {
   _checkContext(this, 'init');
 
-  this.schema.emit('init', this);
+  this.$__schema.emit('init', this);
 
   if (this.$init != null) {
     if (callback) {
@@ -1235,9 +1235,9 @@ Model.init = function init(callback) {
 
   const Promise = PromiseProvider.get();
   const autoIndex = utils.getOption('autoIndex',
-    this.schema.options, this.db.config, this.db.base.options);
+    this.$__schema.options, this.db.config, this.db.base.options);
   const autoCreate = utils.getOption('autoCreate',
-    this.schema.options, this.db.config, this.db.base.options);
+    this.$__schema.options, this.db.config, this.db.base.options);
 
   const _ensureIndexes = autoIndex ?
     cb => this.ensureIndexes({ _automatic: true }, cb) :
@@ -1409,7 +1409,7 @@ Model.cleanIndexes = function cleanIndexes(callback) {
         return cb(err);
       }
 
-      const schemaIndexes = this.schema.indexes();
+      const schemaIndexes = this.$__schema.indexes();
       const toDrop = [];
 
       for (const index of indexes) {
@@ -1787,7 +1787,7 @@ Model.translateAliases = function translateAliases(fields) {
     let alias;
     const translated = [];
     const fieldKeys = key.split('.');
-    let currentSchema = this.schema;
+    let currentSchema = this.$__schema;
     for (const i in fieldKeys) {
       const name = fieldKeys[i];
       if (currentSchema && currentSchema.aliases[name]) {
@@ -2038,11 +2038,11 @@ Model.find = function find(conditions, projection, options, callback) {
   mq.select(projection);
 
   mq.setOptions(options);
-  if (this.schema.discriminatorMapping &&
-      this.schema.discriminatorMapping.isRoot &&
+  if (this.$__schema.discriminatorMapping &&
+      this.$__schema.discriminatorMapping.isRoot &&
       mq.selectedInclusively()) {
     // Need to select discriminator key because original schema doesn't have it
-    mq.select(this.schema.options.discriminatorKey);
+    mq.select(this.$__schema.options.discriminatorKey);
   }
 
   callback = this.$handleCallbackError(callback);
@@ -2151,10 +2151,10 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
   mq.select(projection);
 
   mq.setOptions(options);
-  if (this.schema.discriminatorMapping &&
-      this.schema.discriminatorMapping.isRoot &&
+  if (this.$__schema.discriminatorMapping &&
+      this.$__schema.discriminatorMapping.isRoot &&
       mq.selectedInclusively()) {
-    mq.select(this.schema.options.discriminatorKey);
+    mq.select(this.$__schema.options.discriminatorKey);
   }
 
   callback = this.$handleCallbackError(callback);
@@ -2471,7 +2471,7 @@ Model.findOneAndUpdate = function(conditions, update, options, callback) {
     _isNested: true
   });
 
-  _decorateUpdateWithVersionKey(update, options, this.schema.options.versionKey);
+  _decorateUpdateWithVersionKey(update, options, this.$__schema.options.versionKey);
 
   const mq = new this.Query({}, {}, this, this.collection);
   mq.select(fields);
@@ -2988,7 +2988,7 @@ Model.create = function create(doc, options, callback) {
 
   let args;
   let cb;
-  const discriminatorKey = this.schema.options.discriminatorKey;
+  const discriminatorKey = this.$__schema.options.discriminatorKey;
 
   if (Array.isArray(doc)) {
     args = doc;
@@ -3011,7 +3011,7 @@ Model.create = function create(doc, options, callback) {
         args[0].session == null &&
         last.session != null &&
         last.session.constructor.name === 'ClientSession' &&
-        !this.schema.path('session')) {
+        !this.$__schema.path('session')) {
       // Probably means the user is running into the common mistake of trying
       // to use a spread to specify options, see gh-7535
       console.warn('WARNING: to pass a `session` to `Model.create()` in ' +
@@ -4005,7 +4005,7 @@ Model.aggregate = function aggregate(pipeline, callback) {
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
   return this.db.base._promiseOrCallback(callback, cb => {
-    const schema = this.schema;
+    const schema = this.$__schema;
     let paths = Object.keys(schema.paths);
 
     if (pathsToValidate != null) {
diff --git a/lib/plugins/removeSubdocs.js b/lib/plugins/removeSubdocs.js
index 44b2ea62790..8c3d5b3224d 100644
--- a/lib/plugins/removeSubdocs.js
+++ b/lib/plugins/removeSubdocs.js
@@ -21,7 +21,7 @@ module.exports = function(schema) {
       subdoc.$__remove(cb);
     }, function(error) {
       if (error) {
-        return _this.schema.s.hooks.execPost('remove:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('remove:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
diff --git a/lib/plugins/saveSubdocs.js b/lib/plugins/saveSubdocs.js
index c0a3144e778..c2f5c264797 100644
--- a/lib/plugins/saveSubdocs.js
+++ b/lib/plugins/saveSubdocs.js
@@ -28,7 +28,7 @@ module.exports = function(schema) {
       });
     }, function(error) {
       if (error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
@@ -56,7 +56,7 @@ module.exports = function(schema) {
       });
     }, function(error) {
       if (error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
diff --git a/lib/plugins/sharding.js b/lib/plugins/sharding.js
index 560053ed30c..020ec06c633 100644
--- a/lib/plugins/sharding.js
+++ b/lib/plugins/sharding.js
@@ -56,7 +56,7 @@ module.exports.storeShard = storeShard;
 
 function storeShard() {
   // backwards compat
-  const key = this.schema.options.shardKey || this.schema.options.shardkey;
+  const key = this.$__schema.options.shardKey || this.$__schema.options.shardkey;
   if (!utils.isPOJO(key)) {
     return;
   }
diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index 410a596f3bc..30ded8785f2 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -18,8 +18,8 @@ module.exports = function trackTransaction(schema) {
       if (this.isNew) {
         initialState.isNew = true;
       }
-      if (this.schema.options.versionKey) {
-        initialState.versionKey = this.get(this.schema.options.versionKey);
+      if (this.$__schema.options.versionKey) {
+        initialState.versionKey = this.get(this.$__schema.options.versionKey);
       }
 
       initialState.modifiedPaths = new Set(Object.keys(this.$__.activePaths.states.modify));
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index 4635de1ccfb..c06d5e6e2c4 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -21,7 +21,7 @@ module.exports = function(schema) {
     if (hasValidateBeforeSaveOption) {
       shouldValidate = !!options.validateBeforeSave;
     } else {
-      shouldValidate = this.schema.options.validateBeforeSave;
+      shouldValidate = this.$__schema.options.validateBeforeSave;
     }
 
     // Validate
@@ -33,7 +33,7 @@ module.exports = function(schema) {
         { validateModifiedOnly: options.validateModifiedOnly } :
         null;
       this.validate(validateOptions, function(error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           _this.$op = 'save';
           next(error);
         });
diff --git a/lib/query.js b/lib/query.js
index b115e6f17f7..5092f2c9fc6 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -81,7 +81,7 @@ function Query(conditions, options, model, collection) {
 
   if (model) {
     this.model = model;
-    this.schema = model.schema;
+    this.$__schema = model.schema;
   }
 
   // this is needed because map reduce returns a model that can be queried, but
@@ -4496,7 +4496,7 @@ Query.prototype._post = function(fn) {
 
 Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
   let strict;
-  let schema = this.schema;
+  let schema = this.$__schema;
 
   const discriminatorKey = schema.options.discriminatorKey;
   const baseSchema = schema._baseSchema ? schema._baseSchema : schema;
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index bbbf523addd..cb1578ac668 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -38,7 +38,7 @@ function SingleNestedPath(schema, path, options) {
   this.caster = _createConstructor(schema);
   this.caster.path = path;
   this.caster.prototype.$basePath = path;
-  this.schema = schema;
+  this.$__schema = schema;
   this.$isSingleNested = true;
   SchemaType.call(this, path, options, 'Embedded');
 }
@@ -326,7 +326,7 @@ SingleNestedPath.set = SchemaType.set;
 
 SingleNestedPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
-  const schematype = new this.constructor(this.schema, this.path, options);
+  const schematype = new this.constructor(this.$__schema, this.path, options);
   schematype.validators = this.validators.slice();
   if (this.requiredValidator !== undefined) {
     schematype.requiredValidator = this.requiredValidator;
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index ac88560286e..34832833d63 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -46,7 +46,7 @@ function DocumentArrayPath(key, schema, options, schemaOptions) {
 
   ArrayType.call(this, key, EmbeddedDocument, options);
 
-  this.schema = schema;
+  this.$__schema = schema;
   this.schemaOptions = schemaOptions || {};
   this.$isMongooseDocumentArray = true;
   this.Constructor = EmbeddedDocument;
@@ -75,7 +75,7 @@ function DocumentArrayPath(key, schema, options, schemaOptions) {
   };
   this.$embeddedSchemaType.$isMongooseDocumentArrayElement = true;
   this.$embeddedSchemaType.caster = this.Constructor;
-  this.$embeddedSchemaType.schema = this.schema;
+  this.$embeddedSchemaType.schema = this.$__schema;
 }
 
 /**
@@ -469,7 +469,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
 
 DocumentArrayPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
-  const schematype = new this.constructor(this.path, this.schema, options, this.schemaOptions);
+  const schematype = new this.constructor(this.path, this.$__schema, options, this.schemaOptions);
   schematype.validators = this.validators.slice();
   if (this.requiredValidator !== undefined) {
     schematype.requiredValidator = this.requiredValidator;
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index bc37342467c..7a5df2d3ab4 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -25,9 +25,9 @@ function Subdocument(value, fields, parent, skipId, options) {
   let initedPaths = null;
   if (hasPriorDoc) {
     this._doc = Object.assign({}, options.priorDoc._doc);
-    delete this._doc[this.schema.options.discriminatorKey];
+    delete this._doc[this.$__schema.options.discriminatorKey];
     initedPaths = Object.keys(options.priorDoc._doc || {}).
-      filter(key => key !== this.schema.options.discriminatorKey);
+      filter(key => key !== this.$__schema.options.discriminatorKey);
   }
   if (parent != null) {
     // If setting a nested path, should copy isNew from parent re: gh-7048
@@ -43,7 +43,7 @@ function Subdocument(value, fields, parent, skipId, options) {
       if (!this.$__.activePaths.states.modify[key] &&
           !this.$__.activePaths.states.default[key] &&
           !this.$__.$setCalled.has(key)) {
-        const schematype = this.schema.path(key);
+        const schematype = this.$__schema.path(key);
         const def = schematype == null ? void 0 : schematype.getDefault(this);
         if (def === void 0) {
           delete this._doc[key];
diff --git a/test/document.unit.test.js b/test/document.unit.test.js
index bc7fbd3bc50..0ebdc16dc1b 100644
--- a/test/document.unit.test.js
+++ b/test/document.unit.test.js
@@ -19,7 +19,7 @@ describe('sharding', function() {
       }
     };
     const Stub = function() {
-      this.schema = mockSchema;
+      this.$__schema = mockSchema;
       this.$__ = {};
     };
     Stub.prototype.__proto__ = mongoose.Document.prototype;
@@ -37,7 +37,7 @@ describe('toObject()', function() {
 
   beforeEach(function() {
     Stub = function() {
-      const schema = this.schema = {
+      const schema = this.$__schema = {
         options: { toObject: { minimize: false, virtuals: true } },
         virtuals: { virtual: 'test' }
       };
diff --git a/test/schema.test.js b/test/schema.test.js
index 2dbe512425a..12bb83e59bb 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1682,7 +1682,7 @@ describe('schema', function() {
 
   describe('remove()', function() {
     before(function() {
-      this.schema = new Schema({
+      this.$__schema = new Schema({
         a: String,
         b: {
           c: {
@@ -1696,57 +1696,57 @@ describe('schema', function() {
     });
 
     it('returns the schema instance', function() {
-      const ret = this.schema.clone().remove('g');
+      const ret = this.$__schema.clone().remove('g');
       assert.ok(ret instanceof Schema);
     });
 
     it('removes a single path', function(done) {
-      assert.ok(this.schema.paths.a);
-      this.schema.remove('a');
-      assert.strictEqual(this.schema.path('a'), undefined);
-      assert.strictEqual(this.schema.paths.a, void 0);
+      assert.ok(this.$__schema.paths.a);
+      this.$__schema.remove('a');
+      assert.strictEqual(this.$__schema.path('a'), undefined);
+      assert.strictEqual(this.$__schema.paths.a, void 0);
       done();
     });
 
     it('removes a nested path', function(done) {
-      this.schema.remove('b.c.d');
-      assert.strictEqual(this.schema.path('b'), undefined);
-      assert.strictEqual(this.schema.path('b.c'), undefined);
-      assert.strictEqual(this.schema.path('b.c.d'), undefined);
+      this.$__schema.remove('b.c.d');
+      assert.strictEqual(this.$__schema.path('b'), undefined);
+      assert.strictEqual(this.$__schema.path('b.c'), undefined);
+      assert.strictEqual(this.$__schema.path('b.c.d'), undefined);
       done();
     });
 
     it('removes all children of a nested path (gh-2398)', function(done) {
-      this.schema.remove('b');
-      assert.strictEqual(this.schema.nested['b'], undefined);
-      assert.strictEqual(this.schema.nested['b.c'], undefined);
-      assert.strictEqual(this.schema.path('b.c.d'), undefined);
+      this.$__schema.remove('b');
+      assert.strictEqual(this.$__schema.nested['b'], undefined);
+      assert.strictEqual(this.$__schema.nested['b.c'], undefined);
+      assert.strictEqual(this.$__schema.path('b.c.d'), undefined);
       done();
     });
 
     it('removes an array of paths', function(done) {
-      this.schema.remove(['e', 'f', 'g']);
-      assert.strictEqual(this.schema.path('e'), undefined);
-      assert.strictEqual(this.schema.path('f'), undefined);
-      assert.strictEqual(this.schema.path('g'), undefined);
+      this.$__schema.remove(['e', 'f', 'g']);
+      assert.strictEqual(this.$__schema.path('e'), undefined);
+      assert.strictEqual(this.$__schema.path('f'), undefined);
+      assert.strictEqual(this.$__schema.path('g'), undefined);
       done();
     });
 
     it('works properly with virtuals (gh-2398)', function(done) {
-      this.schema.remove('a');
-      this.schema.virtual('a').get(function() { return 42; });
-      const Test = mongoose.model('gh2398', this.schema);
+      this.$__schema.remove('a');
+      this.$__schema.virtual('a').get(function() { return 42; });
+      const Test = mongoose.model('gh2398', this.$__schema);
       const t = new Test();
       assert.equal(t.a, 42);
       done();
     });
 
     it('methods named toString (gh-4551)', function() {
-      this.schema.methods.toString = function() {
+      this.$__schema.methods.toString = function() {
         return 'test';
       };
       assert.doesNotThrow(() => {
-        mongoose.model('gh4551', this.schema);
+        mongoose.model('gh4551', this.$__schema);
       });
     });
 

From 7093c2bae6917981c49a8b32a79e33a558bdd16e Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 12:06:50 -0500
Subject: [PATCH 1635/2348] made requested changes

---
 lib/document.js                | 13 +++++++++-
 lib/query.js                   |  2 +-
 lib/schema/SingleNestedPath.js |  4 +--
 lib/schema/documentarray.js    |  6 ++---
 test/document.unit.test.js     |  4 +--
 test/schema.test.js            | 46 +++++++++++++++++-----------------
 6 files changed, 43 insertions(+), 32 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 36e880e793d..c47ac8e8d76 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -204,6 +204,17 @@ for (const i in EventEmitter.prototype) {
   Document[i] = EventEmitter.prototype[i];
 }
 
+/**
+ * The document's internal schema.
+ *
+ * @api private
+ * @property schema
+ * @memberOf Document
+ * @instance
+ */
+
+Document.prototype.$__schema;
+
 /**
  * The document's schema.
  *
@@ -213,7 +224,7 @@ for (const i in EventEmitter.prototype) {
  * @instance
  */
 
-Document.prototype.$__schema;
+Document.prototype.schema;
 
 /**
  * Empty object that you can use for storing properties on the document. This
diff --git a/lib/query.js b/lib/query.js
index 5092f2c9fc6..3b253635b06 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -81,7 +81,7 @@ function Query(conditions, options, model, collection) {
 
   if (model) {
     this.model = model;
-    this.$__schema = model.schema;
+    this.schema = model.schema;
   }
 
   // this is needed because map reduce returns a model that can be queried, but
diff --git a/lib/schema/SingleNestedPath.js b/lib/schema/SingleNestedPath.js
index cb1578ac668..bbbf523addd 100644
--- a/lib/schema/SingleNestedPath.js
+++ b/lib/schema/SingleNestedPath.js
@@ -38,7 +38,7 @@ function SingleNestedPath(schema, path, options) {
   this.caster = _createConstructor(schema);
   this.caster.path = path;
   this.caster.prototype.$basePath = path;
-  this.$__schema = schema;
+  this.schema = schema;
   this.$isSingleNested = true;
   SchemaType.call(this, path, options, 'Embedded');
 }
@@ -326,7 +326,7 @@ SingleNestedPath.set = SchemaType.set;
 
 SingleNestedPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
-  const schematype = new this.constructor(this.$__schema, this.path, options);
+  const schematype = new this.constructor(this.schema, this.path, options);
   schematype.validators = this.validators.slice();
   if (this.requiredValidator !== undefined) {
     schematype.requiredValidator = this.requiredValidator;
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 34832833d63..ac88560286e 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -46,7 +46,7 @@ function DocumentArrayPath(key, schema, options, schemaOptions) {
 
   ArrayType.call(this, key, EmbeddedDocument, options);
 
-  this.$__schema = schema;
+  this.schema = schema;
   this.schemaOptions = schemaOptions || {};
   this.$isMongooseDocumentArray = true;
   this.Constructor = EmbeddedDocument;
@@ -75,7 +75,7 @@ function DocumentArrayPath(key, schema, options, schemaOptions) {
   };
   this.$embeddedSchemaType.$isMongooseDocumentArrayElement = true;
   this.$embeddedSchemaType.caster = this.Constructor;
-  this.$embeddedSchemaType.schema = this.$__schema;
+  this.$embeddedSchemaType.schema = this.schema;
 }
 
 /**
@@ -469,7 +469,7 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
 
 DocumentArrayPath.prototype.clone = function() {
   const options = Object.assign({}, this.options);
-  const schematype = new this.constructor(this.path, this.$__schema, options, this.schemaOptions);
+  const schematype = new this.constructor(this.path, this.schema, options, this.schemaOptions);
   schematype.validators = this.validators.slice();
   if (this.requiredValidator !== undefined) {
     schematype.requiredValidator = this.requiredValidator;
diff --git a/test/document.unit.test.js b/test/document.unit.test.js
index 0ebdc16dc1b..bc7fbd3bc50 100644
--- a/test/document.unit.test.js
+++ b/test/document.unit.test.js
@@ -19,7 +19,7 @@ describe('sharding', function() {
       }
     };
     const Stub = function() {
-      this.$__schema = mockSchema;
+      this.schema = mockSchema;
       this.$__ = {};
     };
     Stub.prototype.__proto__ = mongoose.Document.prototype;
@@ -37,7 +37,7 @@ describe('toObject()', function() {
 
   beforeEach(function() {
     Stub = function() {
-      const schema = this.$__schema = {
+      const schema = this.schema = {
         options: { toObject: { minimize: false, virtuals: true } },
         virtuals: { virtual: 'test' }
       };
diff --git a/test/schema.test.js b/test/schema.test.js
index 12bb83e59bb..2dbe512425a 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1682,7 +1682,7 @@ describe('schema', function() {
 
   describe('remove()', function() {
     before(function() {
-      this.$__schema = new Schema({
+      this.schema = new Schema({
         a: String,
         b: {
           c: {
@@ -1696,57 +1696,57 @@ describe('schema', function() {
     });
 
     it('returns the schema instance', function() {
-      const ret = this.$__schema.clone().remove('g');
+      const ret = this.schema.clone().remove('g');
       assert.ok(ret instanceof Schema);
     });
 
     it('removes a single path', function(done) {
-      assert.ok(this.$__schema.paths.a);
-      this.$__schema.remove('a');
-      assert.strictEqual(this.$__schema.path('a'), undefined);
-      assert.strictEqual(this.$__schema.paths.a, void 0);
+      assert.ok(this.schema.paths.a);
+      this.schema.remove('a');
+      assert.strictEqual(this.schema.path('a'), undefined);
+      assert.strictEqual(this.schema.paths.a, void 0);
       done();
     });
 
     it('removes a nested path', function(done) {
-      this.$__schema.remove('b.c.d');
-      assert.strictEqual(this.$__schema.path('b'), undefined);
-      assert.strictEqual(this.$__schema.path('b.c'), undefined);
-      assert.strictEqual(this.$__schema.path('b.c.d'), undefined);
+      this.schema.remove('b.c.d');
+      assert.strictEqual(this.schema.path('b'), undefined);
+      assert.strictEqual(this.schema.path('b.c'), undefined);
+      assert.strictEqual(this.schema.path('b.c.d'), undefined);
       done();
     });
 
     it('removes all children of a nested path (gh-2398)', function(done) {
-      this.$__schema.remove('b');
-      assert.strictEqual(this.$__schema.nested['b'], undefined);
-      assert.strictEqual(this.$__schema.nested['b.c'], undefined);
-      assert.strictEqual(this.$__schema.path('b.c.d'), undefined);
+      this.schema.remove('b');
+      assert.strictEqual(this.schema.nested['b'], undefined);
+      assert.strictEqual(this.schema.nested['b.c'], undefined);
+      assert.strictEqual(this.schema.path('b.c.d'), undefined);
       done();
     });
 
     it('removes an array of paths', function(done) {
-      this.$__schema.remove(['e', 'f', 'g']);
-      assert.strictEqual(this.$__schema.path('e'), undefined);
-      assert.strictEqual(this.$__schema.path('f'), undefined);
-      assert.strictEqual(this.$__schema.path('g'), undefined);
+      this.schema.remove(['e', 'f', 'g']);
+      assert.strictEqual(this.schema.path('e'), undefined);
+      assert.strictEqual(this.schema.path('f'), undefined);
+      assert.strictEqual(this.schema.path('g'), undefined);
       done();
     });
 
     it('works properly with virtuals (gh-2398)', function(done) {
-      this.$__schema.remove('a');
-      this.$__schema.virtual('a').get(function() { return 42; });
-      const Test = mongoose.model('gh2398', this.$__schema);
+      this.schema.remove('a');
+      this.schema.virtual('a').get(function() { return 42; });
+      const Test = mongoose.model('gh2398', this.schema);
       const t = new Test();
       assert.equal(t.a, 42);
       done();
     });
 
     it('methods named toString (gh-4551)', function() {
-      this.$__schema.methods.toString = function() {
+      this.schema.methods.toString = function() {
         return 'test';
       };
       assert.doesNotThrow(() => {
-        mongoose.model('gh4551', this.$__schema);
+        mongoose.model('gh4551', this.schema);
       });
     });
 

From 8c2691b74266c1cfad6960e89a37c1e4a939dec8 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 12:12:39 -0500
Subject: [PATCH 1636/2348] made more fixes

---
 lib/browserDocument.js                    | 4 ++--
 lib/helpers/timestamps/setupTimestamps.js | 2 +-
 lib/plugins/removeSubdocs.js              | 2 +-
 lib/plugins/saveSubdocs.js                | 4 ++--
 lib/plugins/sharding.js                   | 2 +-
 lib/plugins/trackTransaction.js           | 4 ++--
 lib/plugins/validateBeforeSave.js         | 4 ++--
 lib/query.js                              | 2 +-
 8 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/lib/browserDocument.js b/lib/browserDocument.js
index 259ac66210f..a44f3077e01 100644
--- a/lib/browserDocument.js
+++ b/lib/browserDocument.js
@@ -35,10 +35,10 @@ function Document(obj, schema, fields, skipId, skipInit) {
   }
 
   // When creating EmbeddedDocument, it already has the schema and he doesn't need the _id
-  schema = this.$__schema || schema;
+  schema = this.schema || schema;
 
   // Generate ObjectId if it is missing, but it requires a scheme
-  if (!this.$__schema && schema.options._id) {
+  if (!this.schema && schema.options._id) {
     obj = obj || {};
 
     if (obj._id === undefined) {
diff --git a/lib/helpers/timestamps/setupTimestamps.js b/lib/helpers/timestamps/setupTimestamps.js
index 146334cabb9..752a565738c 100644
--- a/lib/helpers/timestamps/setupTimestamps.js
+++ b/lib/helpers/timestamps/setupTimestamps.js
@@ -97,7 +97,7 @@ module.exports = function setupTimestamps(schema, timestamps) {
       currentTime() :
       this.model.base.now();
     applyTimestampsToUpdate(now, createdAt, updatedAt, this.getUpdate(),
-      this.options, this.$__schema);
+      this.options, this.schema);
     applyTimestampsToChildren(now, this.getUpdate(), this.model.schema);
     next();
   }
diff --git a/lib/plugins/removeSubdocs.js b/lib/plugins/removeSubdocs.js
index 8c3d5b3224d..44b2ea62790 100644
--- a/lib/plugins/removeSubdocs.js
+++ b/lib/plugins/removeSubdocs.js
@@ -21,7 +21,7 @@ module.exports = function(schema) {
       subdoc.$__remove(cb);
     }, function(error) {
       if (error) {
-        return _this.$__schema.s.hooks.execPost('remove:error', _this, [_this], { error: error }, function(error) {
+        return _this.schema.s.hooks.execPost('remove:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
diff --git a/lib/plugins/saveSubdocs.js b/lib/plugins/saveSubdocs.js
index c2f5c264797..c0a3144e778 100644
--- a/lib/plugins/saveSubdocs.js
+++ b/lib/plugins/saveSubdocs.js
@@ -28,7 +28,7 @@ module.exports = function(schema) {
       });
     }, function(error) {
       if (error) {
-        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
@@ -56,7 +56,7 @@ module.exports = function(schema) {
       });
     }, function(error) {
       if (error) {
-        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
diff --git a/lib/plugins/sharding.js b/lib/plugins/sharding.js
index 020ec06c633..560053ed30c 100644
--- a/lib/plugins/sharding.js
+++ b/lib/plugins/sharding.js
@@ -56,7 +56,7 @@ module.exports.storeShard = storeShard;
 
 function storeShard() {
   // backwards compat
-  const key = this.$__schema.options.shardKey || this.$__schema.options.shardkey;
+  const key = this.schema.options.shardKey || this.schema.options.shardkey;
   if (!utils.isPOJO(key)) {
     return;
   }
diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index 30ded8785f2..410a596f3bc 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -18,8 +18,8 @@ module.exports = function trackTransaction(schema) {
       if (this.isNew) {
         initialState.isNew = true;
       }
-      if (this.$__schema.options.versionKey) {
-        initialState.versionKey = this.get(this.$__schema.options.versionKey);
+      if (this.schema.options.versionKey) {
+        initialState.versionKey = this.get(this.schema.options.versionKey);
       }
 
       initialState.modifiedPaths = new Set(Object.keys(this.$__.activePaths.states.modify));
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index c06d5e6e2c4..4635de1ccfb 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -21,7 +21,7 @@ module.exports = function(schema) {
     if (hasValidateBeforeSaveOption) {
       shouldValidate = !!options.validateBeforeSave;
     } else {
-      shouldValidate = this.$__schema.options.validateBeforeSave;
+      shouldValidate = this.schema.options.validateBeforeSave;
     }
 
     // Validate
@@ -33,7 +33,7 @@ module.exports = function(schema) {
         { validateModifiedOnly: options.validateModifiedOnly } :
         null;
       this.validate(validateOptions, function(error) {
-        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           _this.$op = 'save';
           next(error);
         });
diff --git a/lib/query.js b/lib/query.js
index 3b253635b06..b115e6f17f7 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4496,7 +4496,7 @@ Query.prototype._post = function(fn) {
 
 Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
   let strict;
-  let schema = this.$__schema;
+  let schema = this.schema;
 
   const discriminatorKey = schema.options.discriminatorKey;
   const baseSchema = schema._baseSchema ? schema._baseSchema : schema;

From c9befbfa5cde1a5480f171d46ad85d157b32e3f5 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 12:28:44 -0500
Subject: [PATCH 1637/2348] made all requested changes

---
 lib/model.js | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 77bbf37fcc2..affd43ac014 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1223,7 +1223,7 @@ for (const i in EventEmitter.prototype) {
 Model.init = function init(callback) {
   _checkContext(this, 'init');
 
-  this.$__schema.emit('init', this);
+  this.schema.emit('init', this);
 
   if (this.$init != null) {
     if (callback) {
@@ -1235,9 +1235,9 @@ Model.init = function init(callback) {
 
   const Promise = PromiseProvider.get();
   const autoIndex = utils.getOption('autoIndex',
-    this.$__schema.options, this.db.config, this.db.base.options);
+    this.schema.options, this.db.config, this.db.base.options);
   const autoCreate = utils.getOption('autoCreate',
-    this.$__schema.options, this.db.config, this.db.base.options);
+    this.schema.options, this.db.config, this.db.base.options);
 
   const _ensureIndexes = autoIndex ?
     cb => this.ensureIndexes({ _automatic: true }, cb) :
@@ -1409,7 +1409,7 @@ Model.cleanIndexes = function cleanIndexes(callback) {
         return cb(err);
       }
 
-      const schemaIndexes = this.$__schema.indexes();
+      const schemaIndexes = this.schema.indexes();
       const toDrop = [];
 
       for (const index of indexes) {
@@ -1787,7 +1787,7 @@ Model.translateAliases = function translateAliases(fields) {
     let alias;
     const translated = [];
     const fieldKeys = key.split('.');
-    let currentSchema = this.$__schema;
+    let currentSchema = this.schema;
     for (const i in fieldKeys) {
       const name = fieldKeys[i];
       if (currentSchema && currentSchema.aliases[name]) {
@@ -2038,11 +2038,11 @@ Model.find = function find(conditions, projection, options, callback) {
   mq.select(projection);
 
   mq.setOptions(options);
-  if (this.$__schema.discriminatorMapping &&
-      this.$__schema.discriminatorMapping.isRoot &&
+  if (this.schema.discriminatorMapping &&
+      this.schema.discriminatorMapping.isRoot &&
       mq.selectedInclusively()) {
     // Need to select discriminator key because original schema doesn't have it
-    mq.select(this.$__schema.options.discriminatorKey);
+    mq.select(this.schema.options.discriminatorKey);
   }
 
   callback = this.$handleCallbackError(callback);
@@ -2151,10 +2151,10 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
   mq.select(projection);
 
   mq.setOptions(options);
-  if (this.$__schema.discriminatorMapping &&
-      this.$__schema.discriminatorMapping.isRoot &&
+  if (this.schema.discriminatorMapping &&
+      this.schema.discriminatorMapping.isRoot &&
       mq.selectedInclusively()) {
-    mq.select(this.$__schema.options.discriminatorKey);
+    mq.select(this.schema.options.discriminatorKey);
   }
 
   callback = this.$handleCallbackError(callback);
@@ -2471,7 +2471,7 @@ Model.findOneAndUpdate = function(conditions, update, options, callback) {
     _isNested: true
   });
 
-  _decorateUpdateWithVersionKey(update, options, this.$__schema.options.versionKey);
+  _decorateUpdateWithVersionKey(update, options, this.schema.options.versionKey);
 
   const mq = new this.Query({}, {}, this, this.collection);
   mq.select(fields);
@@ -2988,7 +2988,7 @@ Model.create = function create(doc, options, callback) {
 
   let args;
   let cb;
-  const discriminatorKey = this.$__schema.options.discriminatorKey;
+  const discriminatorKey = this.schema.options.discriminatorKey;
 
   if (Array.isArray(doc)) {
     args = doc;
@@ -3011,7 +3011,7 @@ Model.create = function create(doc, options, callback) {
         args[0].session == null &&
         last.session != null &&
         last.session.constructor.name === 'ClientSession' &&
-        !this.$__schema.path('session')) {
+        !this.schema.path('session')) {
       // Probably means the user is running into the common mistake of trying
       // to use a spread to specify options, see gh-7535
       console.warn('WARNING: to pass a `session` to `Model.create()` in ' +
@@ -4005,7 +4005,7 @@ Model.aggregate = function aggregate(pipeline, callback) {
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
   return this.db.base._promiseOrCallback(callback, cb => {
-    const schema = this.$__schema;
+    const schema = this.schema;
     let paths = Object.keys(schema.paths);
 
     if (pathsToValidate != null) {

From 7c55a77fe4af648094a0d5820dd75d3d292253ed Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 15:02:05 -0500
Subject: [PATCH 1638/2348] made necessary changes

---
 lib/document.js                               | 34 +++++++++----------
 lib/helpers/document/cleanModifiedSubpaths.js |  2 +-
 lib/model.js                                  |  2 +-
 lib/query.js                                  |  1 -
 lib/types/subdocument.js                      |  4 +--
 5 files changed, 21 insertions(+), 22 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index c47ac8e8d76..b59def23451 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -344,7 +344,7 @@ function $__hasIncludedChildren(fields) {
  */
 
 function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isBeforeSetters, pathsToSkip) {
-  const paths = Object.keys(doc.schema.paths);
+  const paths = Object.keys(doc.$__schema.paths);
   const plen = paths.length;
 
   for (let i = 0; i < plen; ++i) {
@@ -356,7 +356,7 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
       continue;
     }
 
-    const type = doc.schema.paths[p];
+    const type = doc.$__schema.paths[p];
     const path = p.indexOf('.') === -1 ? [p] : p.split('.');
     const len = path.length;
     let included = false;
@@ -670,12 +670,12 @@ function init(self, obj, doc, opts, prefix) {
   function _init(index) {
     i = keys[index];
     path = prefix + i;
-    schema = self.schema.path(path);
+    schema = self.$__schema.path(path);
 
     // Should still work if not a model-level discriminator, but should not be
     // necessary. This is *only* to catch the case where we queried using the
     // base model and the discriminated model has a projection
-    if (self.schema.$isRootDiscriminator && !self.isSelected(path)) {
+    if (self.$__schema.$isRootDiscriminator && !self.isSelected(path)) {
       return;
     }
 
@@ -1595,7 +1595,7 @@ Document.prototype.get = function(path, type, options) {
 
   let schema = this.$__path(path);
   if (schema == null) {
-    schema = this.$__schema.virtualpath(path);
+    schema = this.schema.virtualpath(path);
   }
   if (schema instanceof MixedSchema) {
     const virtual = this.$__schema.virtualpath(path);
@@ -1611,7 +1611,7 @@ Document.prototype.get = function(path, type, options) {
   }
 
   // Might need to change path for top-level alias
-  if (typeof this.$__schema.aliases[pieces[0]] == 'string') {
+  if (typeof this.schema.aliases[pieces[0]] == 'string') {
     pieces[0] = this.$__schema.aliases[pieces[0]];
   }
 
@@ -1637,7 +1637,7 @@ Document.prototype.get = function(path, type, options) {
 
   if (schema != null && options.getters !== false) {
     obj = schema.applyGetters(obj, this);
-  } else if (this.$__schema.nested[path] && options.virtuals) {
+  } else if (this.schema.nested[path] && options.virtuals) {
     // Might need to apply virtuals if this is a nested path
     return applyVirtuals(this, utils.clone(obj) || {}, { path: path });
   }
@@ -1668,7 +1668,7 @@ Document.prototype.$__path = function(path) {
   if (adhocType) {
     return adhocType;
   }
-  return this.$__schema.path(path);
+  return this.schema.path(path);
 };
 
 /**
@@ -2251,7 +2251,7 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
 
 function _evaluateRequiredFunctions(doc) {
   Object.keys(doc.$__.activePaths.states.require).forEach(path => {
-    const p = doc.schema.path(path);
+    const p = doc.$__schema.path(path);
 
     if (p != null && typeof p.originalRequiredValue === 'function') {
       doc.$__.cachedRequired[path] = p.originalRequiredValue.call(doc, doc);
@@ -2312,7 +2312,7 @@ function _getPathsToValidate(doc) {
   // gh-661: if a whole array is modified, make sure to run validation on all
   // the children as well
   for (const path of paths) {
-    const _pathType = doc.schema.path(path);
+    const _pathType = doc.$__schema.path(path);
     if (!_pathType ||
         !_pathType.$isMongooseArray ||
         // To avoid potential performance issues, skip doc arrays whose children
@@ -2341,7 +2341,7 @@ function _getPathsToValidate(doc) {
 
   const flattenOptions = { skipArrays: true };
   for (const pathToCheck of paths) {
-    if (doc.schema.nested[pathToCheck]) {
+    if (doc.$__schema.nested[pathToCheck]) {
       let _v = doc.$__getValue(pathToCheck);
       if (isMongooseObject(_v)) {
         _v = _v.toObject({ transform: false });
@@ -2356,11 +2356,11 @@ function _getPathsToValidate(doc) {
     // Single nested paths (paths embedded under single nested subdocs) will
     // be validated on their own when we call `validate()` on the subdoc itself.
     // Re: gh-8468
-    if (doc.schema.singleNestedPaths.hasOwnProperty(path)) {
+    if (doc.$__schema.singleNestedPaths.hasOwnProperty(path)) {
       paths.delete(path);
       continue;
     }
-    const _pathType = doc.schema.path(path);
+    const _pathType = doc.$__schema.path(path);
     if (!_pathType || !_pathType.$isSchemaMap) {
       continue;
     }
@@ -3047,7 +3047,7 @@ Document.prototype.$__setSchema = function(schema) {
   for (const key of Object.keys(schema.virtuals)) {
     schema.virtuals[key]._applyDefaultGetters();
   }
-
+  this.schema = schema;
   this.$__schema = schema;
   this[documentSchemaSymbol] = schema;
 };
@@ -3147,7 +3147,7 @@ Document.prototype.$__getAllSubdocs = function() {
  */
 
 function applyQueue(doc) {
-  const q = doc.schema && doc.schema.callQueue;
+  const q = doc.$__schema && doc.$__schema.callQueue;
   if (!q.length) {
     return;
   }
@@ -3558,7 +3558,7 @@ function applyVirtuals(self, json, options, toObjectOptions) {
  */
 
 function applyGetters(self, json, options) {
-  const schema = self.schema;
+  const schema = self.$__schema;
   const paths = Object.keys(schema.paths);
   let i = paths.length;
   let path;
@@ -3613,7 +3613,7 @@ function applyGetters(self, json, options) {
  */
 
 function applySchemaTypeTransforms(self, json) {
-  const schema = self.schema;
+  const schema = self.$__schema;
   const paths = Object.keys(schema.paths || {});
   const cur = self._doc;
 
diff --git a/lib/helpers/document/cleanModifiedSubpaths.js b/lib/helpers/document/cleanModifiedSubpaths.js
index 252d34824df..98de475364f 100644
--- a/lib/helpers/document/cleanModifiedSubpaths.js
+++ b/lib/helpers/document/cleanModifiedSubpaths.js
@@ -14,7 +14,7 @@ module.exports = function cleanModifiedSubpaths(doc, path, options) {
   }
   for (const modifiedPath of Object.keys(doc.$__.activePaths.states.modify)) {
     if (skipDocArrays) {
-      const schemaType = doc.schema.path(modifiedPath);
+      const schemaType = doc.$__schema.path(modifiedPath);
       if (schemaType && schemaType.$isMongooseDocumentArray) {
         continue;
       }
diff --git a/lib/model.js b/lib/model.js
index affd43ac014..ed102992190 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4758,7 +4758,7 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
   applyHooks(model, schema);
   applyStaticHooks(model, schema.s.hooks, schema.statics);
 
-  model.schema = model.prototype.schema;
+  model.schema = model.prototype.$__schema;
   model.collection = model.prototype.collection;
 
   // Create custom query constructor
diff --git a/lib/query.js b/lib/query.js
index b115e6f17f7..b10950676eb 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4752,7 +4752,6 @@ Query.prototype.cast = function(model, obj) {
   obj || (obj = this._conditions);
 
   model = model || this.model;
-
   const discriminatorKey = model.schema.options.discriminatorKey;
   if (obj != null &&
       obj.hasOwnProperty(discriminatorKey)) {
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 7a5df2d3ab4..4e0976e4bf2 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -25,9 +25,9 @@ function Subdocument(value, fields, parent, skipId, options) {
   let initedPaths = null;
   if (hasPriorDoc) {
     this._doc = Object.assign({}, options.priorDoc._doc);
-    delete this._doc[this.$__schema.options.discriminatorKey];
+    delete this._doc[this.schema.options.discriminatorKey];
     initedPaths = Object.keys(options.priorDoc._doc || {}).
-      filter(key => key !== this.$__schema.options.discriminatorKey);
+      filter(key => key !== this.schema.options.discriminatorKey);
   }
   if (parent != null) {
     // If setting a nested path, should copy isNew from parent re: gh-7048

From 07d663f2342fc1f4f0969b53a51a2da15212a6e7 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 16:31:43 -0500
Subject: [PATCH 1639/2348] changed 1 line in document.js

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index b59def23451..498235955f2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3613,7 +3613,7 @@ function applyGetters(self, json, options) {
  */
 
 function applySchemaTypeTransforms(self, json) {
-  const schema = self.$__schema;
+  const schema = self.schema;
   const paths = Object.keys(schema.paths || {});
   const cur = self._doc;
 

From 25ba5f17a08ed14628fad33fcb737634d571f58d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 21 Jan 2021 17:17:12 -0500
Subject: [PATCH 1640/2348] added failing test

---
 lib/schema.js         |  1 -
 test/document.test.js | 12 ++++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index af350ffbaa9..7da1456b6d5 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -591,7 +591,6 @@ reserved.isNew =
 reserved.populated =
 reserved.remove =
 reserved.save =
-reserved.schema =
 reserved.toObject =
 reserved.validate = 1;
 
diff --git a/test/document.test.js b/test/document.test.js
index 31836103fd5..efbf71d1692 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9850,4 +9850,16 @@ describe('document', function() {
       assert.ok(!_doc);
     });
   });
+  it('handles paths named `schema` gh-8798', function() {
+    const schema = new Schema({
+      schema: String,
+      name: String
+    });
+    const Test = db.model('Test', schema);
+    return co(function*() {
+      const doc = yield Test.create({ schema: 'foo' }, { name: 'frank' });
+      yield doc.save();
+      assert.ok(doc);
+    });
+  });
 });

From 957fbf2d2da6d07654eb417cead50a60bcf15738 Mon Sep 17 00:00:00 2001
From: Hannu Huhtanen <hannu.huhtanen@unity3d.com>
Date: Fri, 22 Jan 2021 13:13:53 +0200
Subject: [PATCH 1641/2348] Made ValidationError.toJSON to include the error
 name correctly

---
 lib/error/validation.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/error/validation.js b/lib/error/validation.js
index ccae07adff1..7b4047620d1 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -67,13 +67,14 @@ if (util.inspect.custom) {
 
 /*!
  * Helper for JSON.stringify
+ * Ensure `name` and `message` show up in toJSON output re: gh-9847
  */
 Object.defineProperty(ValidationError.prototype, 'toJSON', {
   enumerable: false,
   writable: false,
   configurable: true,
   value: function() {
-    return Object.assign({}, this, { message: this.message });
+    return Object.assign({}, this, { name: this.name, message: this.message });
   }
 });
 

From 89a297bf61084449e8966b6f25d7a54b0564ff84 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 22 Jan 2021 12:30:04 -0500
Subject: [PATCH 1642/2348] test(document): repro #9838

---
 test/document.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 31836103fd5..90b1f718fe3 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9850,4 +9850,32 @@ describe('document', function() {
       assert.ok(!_doc);
     });
   });
+
+  it('object setters will be applied for each object in array after populate (gh-9838)', function() {
+    const updatedElID = '123456789012345678901234';
+
+    const ElementSchema = new Schema({
+      name: 'string',
+      nested: [{ type: Schema.Types.ObjectId, ref: 'Nested' }]
+    });
+
+    const NestedSchema = new Schema({});
+
+    const Element = db.model('Test', ElementSchema);
+    const NestedElement = db.model('Nested', NestedSchema);
+
+    return co(function*() {
+      const nes = new NestedElement({});
+      yield nes.save();
+      const ele = new Element({ nested: [nes.id], name: 'test' });
+      yield ele.save();
+
+      const ss = yield Element.findById(ele._id).populate({ path: 'nested', model: NestedElement });
+      ss.nested = [updatedElID];
+      yield ss.save();
+
+      assert.ok(typeof ss.nested[0] !== 'string');
+      assert.equal(ss.nested[0].toHexString(), updatedElID);
+    });
+  });
 });

From cdba3872331e67a371e89a3d5bfe5f15259f1b4c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 22 Jan 2021 12:30:14 -0500
Subject: [PATCH 1643/2348] fix(document): apply setters on each element of the
 array when setting a populated array

Fix #9838
---
 lib/schema/array.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index e0321c6c7fa..8a304189623 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -348,7 +348,7 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     }
 
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
-    if (isPopulated) {
+    if (isPopulated && init) {
       return value;
     }
 

From 2373c07136629d302fd9182cd6186c30ca4afee2 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 25 Jan 2021 10:28:35 -0500
Subject: [PATCH 1644/2348] fix: gh-8798

adding $__ in front of schema at line 1671 let all the toObject tests pass and fixed the maximum stack error
---
 lib/document.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 498235955f2..f7c83bceffc 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1668,7 +1668,7 @@ Document.prototype.$__path = function(path) {
   if (adhocType) {
     return adhocType;
   }
-  return this.schema.path(path);
+  return this.$__schema.path(path);
 };
 
 /**
@@ -3047,7 +3047,9 @@ Document.prototype.$__setSchema = function(schema) {
   for (const key of Object.keys(schema.virtuals)) {
     schema.virtuals[key]._applyDefaultGetters();
   }
-  this.schema = schema;
+  if (schema.path('schema') == null) {
+    this.schema = schema;
+  }
   this.$__schema = schema;
   this[documentSchemaSymbol] = schema;
 };

From a05005c208a24e92945e6fee87cff71cce9e5291 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 25 Jan 2021 20:15:10 -0500
Subject: [PATCH 1645/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 5d6ac1b4ede..d1c3c3ed764 100644
--- a/index.pug
+++ b/index.pug
@@ -349,6 +349,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.nettikasinot.media/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-media/2dba7da/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://kajino.com/">
+                <img class="sponsor" src="https://images.opencollective.com/kajino-com/02c99ee/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 229bf8641f47e0b3eff725a13446546bcf2be7ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Jan 2021 10:50:41 -0500
Subject: [PATCH 1646/2348] fix(index.d.ts): allow setting `SchemaType#enum` to
 TypeScript enum with `required: true`

Fix #9546
---
 index.d.ts                   |  2 +-
 test/typescript/main.test.js |  2 +-
 test/typescript/schema.ts    | 23 +++++++++++++++++------
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 36a74e37ccc..02fea8cdb10 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1421,7 +1421,7 @@ declare module 'mongoose' {
     set?: (value: T, schematype?: this) => any;
 
     /** array of allowed values for this path. Allowed for strings, numbers, and arrays of strings */
-    enum?: Array<string | number | null>
+    enum?: Array<string | number | null> | { [path: string]: string | number | null };
 
     /** The default [subtype](http://bsonspec.org/spec.html) associated with this buffer when it is stored in MongoDB. Only allowed for buffer paths */
     subtype?: number
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index c3a44258eb5..9a968ef31e1 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -174,7 +174,7 @@ describe('typescript syntax', function() {
   });
 
   it('schema', function() {
-    const errors = runTest('schema.ts');
+    const errors = runTest('schema.ts', { strict: true });
     if (process.env.D && errors.length) {
       console.log(errors);
     }
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 6c9b10488ae..79348e2ba29 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -1,16 +1,27 @@
 import { Schema } from 'mongoose';
 
-const schema: Schema = new Schema({
-  name: String,
-  enumWithNull: {
+enum Genre {
+  Action,
+  Adventure,
+  Comedy
+}
+
+const movieSchema: Schema = new Schema({
+  title: String,
+  featuredIn: {
     type: String,
-    enum: ['Test', null],
+    enum: ['Favorites', null],
     default: null
   },
-  numberWithMax: {
+  rating: {
     type: Number,
     required: [true, 'Required'],
     min: [0, 'MinValue'],
-    max: [24, 'MaxValue']
+    max: [5, 'MaxValue']
+  },
+  genre: {
+    type: String,
+    enum: Genre,
+    required: true
   }
 });

From cc8dcbf2afc3729a2ce3d561a4d7ebc1722a68bd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Jan 2021 10:53:07 -0500
Subject: [PATCH 1647/2348] chore(package.json): disable no-unused-vars so
 linter doesn't complain about test files

---
 package.json | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 614c4cc209f..98aafadf2c0 100644
--- a/package.json
+++ b/package.json
@@ -120,7 +120,8 @@
         ],
         "rules": {
           "@typescript-eslint/no-explicit-any": "off",
-          "@typescript-eslint/ban-types": "off"
+          "@typescript-eslint/ban-types": "off",
+          "@typescript-eslint/no-unused-vars": "off"
         }
       }
     ],

From d70ff4f7e3082ceccd4ceb571ffb4cd91c0e6c78 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Jan 2021 11:07:18 -0500
Subject: [PATCH 1648/2348] fix(index.d.ts): indicate that `Document#remove()`
 returns a promise, not a query

Fix #9826
---
 index.d.ts                   |  2 +-
 test/typescript/document.ts  | 18 ++++++++++++++++++
 test/typescript/main.test.js |  8 ++++++++
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/document.ts

diff --git a/index.d.ts b/index.d.ts
index 02fea8cdb10..3d969ff6206 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -546,7 +546,7 @@ declare module 'mongoose' {
     populated(path: string): any;
 
     /** Removes this document from the db. */
-    remove(options?: QueryOptions): Query<any, this>;
+    remove(options?: QueryOptions): Promise<this>;
     remove(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Sends a replaceOne command with this document `_id` as the query selector. */
diff --git a/test/typescript/document.ts b/test/typescript/document.ts
new file mode 100644
index 00000000000..0db7014ac54
--- /dev/null
+++ b/test/typescript/document.ts
@@ -0,0 +1,18 @@
+import { Schema, model, Document } from 'mongoose';
+
+const schema: Schema = new Schema({ name: { type: 'String' } });
+
+interface ITestBase {
+  name?: string;
+}
+
+interface ITest extends ITestBase, Document {}
+
+const Test = model<ITest>('Test', schema);
+
+void async function main() {
+  const doc: ITest = await Test.findOne().orFail();
+
+  const p: Promise<ITest> = doc.remove();
+  await p;
+}();
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 9a968ef31e1..fc9d2f06f46 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -180,6 +180,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('document', function() {
+    const errors = runTest('document.ts', { strict: true });
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file, configOverride) {

From 0739a4d9b35d1a5cf6a6d73c700cce1f2d521d81 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Jan 2021 12:06:28 -0500
Subject: [PATCH 1649/2348] fix(document): avoid infinite recursion when using
 `schema` as a schema path

---
 lib/document.js                   | 15 +++++------
 lib/helpers/document/compile.js   |  7 +++++
 lib/model.js                      | 16 +++++------
 lib/plugins/sharding.js           |  2 +-
 lib/plugins/validateBeforeSave.js |  4 +--
 test/document.test.js             | 44 ++++++++++++++++++++++++++++++-
 6 files changed, 68 insertions(+), 20 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f7c83bceffc..536ce4a6dfd 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1595,7 +1595,7 @@ Document.prototype.get = function(path, type, options) {
 
   let schema = this.$__path(path);
   if (schema == null) {
-    schema = this.schema.virtualpath(path);
+    schema = this.$__schema.virtualpath(path);
   }
   if (schema instanceof MixedSchema) {
     const virtual = this.$__schema.virtualpath(path);
@@ -1611,7 +1611,7 @@ Document.prototype.get = function(path, type, options) {
   }
 
   // Might need to change path for top-level alias
-  if (typeof this.schema.aliases[pieces[0]] == 'string') {
+  if (typeof this.$__schema.aliases[pieces[0]] == 'string') {
     pieces[0] = this.$__schema.aliases[pieces[0]];
   }
 
@@ -1637,7 +1637,7 @@ Document.prototype.get = function(path, type, options) {
 
   if (schema != null && options.getters !== false) {
     obj = schema.applyGetters(obj, this);
-  } else if (this.schema.nested[path] && options.virtuals) {
+  } else if (this.$__schema.nested[path] && options.virtuals) {
     // Might need to apply virtuals if this is a nested path
     return applyVirtuals(this, utils.clone(obj) || {}, { path: path });
   }
@@ -2346,12 +2346,11 @@ function _getPathsToValidate(doc) {
       if (isMongooseObject(_v)) {
         _v = _v.toObject({ transform: false });
       }
-      const flat = flatten(_v, pathToCheck, flattenOptions, doc.schema);
+      const flat = flatten(_v, pathToCheck, flattenOptions, doc.$__schema);
       Object.keys(flat).forEach(addToPaths);
     }
   }
 
-
   for (const path of paths) {
     // Single nested paths (paths embedded under single nested subdocs) will
     // be validated on their own when we call `validate()` on the subdoc itself.
@@ -3501,7 +3500,7 @@ function minimize(obj) {
  */
 
 function applyVirtuals(self, json, options, toObjectOptions) {
-  const schema = self.schema;
+  const schema = self.$__schema;
   const paths = Object.keys(schema.virtuals);
   let i = paths.length;
   const numPaths = i;
@@ -3615,7 +3614,7 @@ function applyGetters(self, json, options) {
  */
 
 function applySchemaTypeTransforms(self, json) {
-  const schema = self.schema;
+  const schema = self.$__schema;
   const paths = Object.keys(schema.paths || {});
   const cur = self._doc;
 
@@ -3658,7 +3657,7 @@ function throwErrorIfPromise(path, transformedValue) {
  */
 
 function omitDeselectedFields(self, json) {
-  const schema = self.schema;
+  const schema = self.$__schema;
   const paths = Object.keys(schema.paths || {});
   const cur = self._doc;
 
diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index def45e67b23..47e15f4d6cc 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -74,6 +74,13 @@ function defineKey(prop, subprops, prototype, prefix, keys, options) {
             value: prototype.schema
           });
 
+          Object.defineProperty(nested, '$__schema', {
+            enumerable: false,
+            configurable: true,
+            writable: false,
+            value: prototype.schema
+          });
+
           Object.defineProperty(nested, documentSchemaSymbol, {
             enumerable: false,
             configurable: true,
diff --git a/lib/model.js b/lib/model.js
index ed102992190..5f2bcdf7695 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -413,7 +413,7 @@ Model.prototype.$__save = function(options, callback) {
  */
 
 function generateVersionError(doc, modifiedPaths) {
-  const key = doc.schema.options.versionKey;
+  const key = doc.$__schema.options.versionKey;
   if (!key) {
     return null;
   }
@@ -512,7 +512,7 @@ Model.prototype.save = function(options, fn) {
  * @return {Boolean} true if versioning should be skipped for the given path
  */
 function shouldSkipVersioning(self, path) {
-  const skipVersioning = self.schema.options.skipVersioning;
+  const skipVersioning = self.$__schema.options.skipVersioning;
   if (!skipVersioning) return false;
 
   // Remove any array indexes from the path
@@ -539,7 +539,7 @@ function operand(self, where, delta, data, val, op) {
   if (!delta[op]) delta[op] = {};
   delta[op][data.path] = val;
   // disabled versioning?
-  if (self.schema.options.versionKey === false) return;
+  if (self.$__schema.options.versionKey === false) return;
 
   // path excluded from versioning?
   if (shouldSkipVersioning(self, data.path)) return;
@@ -547,7 +547,7 @@ function operand(self, where, delta, data, val, op) {
   // already marked for versioning?
   if (VERSION_ALL === (VERSION_ALL & self.$__.version)) return;
 
-  if (self.schema.options.optimisticConcurrency) {
+  if (self.$__schema.options.optimisticConcurrency) {
     self.$__.version = VERSION_ALL;
     return;
   }
@@ -3311,8 +3311,8 @@ Model.$__insertMany = function(arr, options, callback) {
       return;
     }
     const docObjects = docAttributes.map(function(doc) {
-      if (doc.schema.options.versionKey) {
-        doc[doc.schema.options.versionKey] = 0;
+      if (doc.$__schema.options.versionKey) {
+        doc[doc.$__schema.options.versionKey] = 0;
       }
       if (doc.initializeTimestamps) {
         return doc.initializeTimestamps().toObject(internalToObjectOptions);
@@ -4824,13 +4824,13 @@ Model.__subclass = function subclass(conn, schema, collection) {
 
   const s = schema && typeof schema !== 'string'
     ? schema
-    : _this.prototype.schema;
+    : _this.prototype.$__schema;
 
   const options = s.options || {};
   const _userProvidedOptions = s._userProvidedOptions || {};
 
   if (!collection) {
-    collection = _this.prototype.schema.get('collection') ||
+    collection = _this.prototype.$__schema.get('collection') ||
       utils.toCollectionName(_this.modelName, this.base.pluralize());
   }
 
diff --git a/lib/plugins/sharding.js b/lib/plugins/sharding.js
index 560053ed30c..020ec06c633 100644
--- a/lib/plugins/sharding.js
+++ b/lib/plugins/sharding.js
@@ -56,7 +56,7 @@ module.exports.storeShard = storeShard;
 
 function storeShard() {
   // backwards compat
-  const key = this.schema.options.shardKey || this.schema.options.shardkey;
+  const key = this.$__schema.options.shardKey || this.$__schema.options.shardkey;
   if (!utils.isPOJO(key)) {
     return;
   }
diff --git a/lib/plugins/validateBeforeSave.js b/lib/plugins/validateBeforeSave.js
index 4635de1ccfb..c06d5e6e2c4 100644
--- a/lib/plugins/validateBeforeSave.js
+++ b/lib/plugins/validateBeforeSave.js
@@ -21,7 +21,7 @@ module.exports = function(schema) {
     if (hasValidateBeforeSaveOption) {
       shouldValidate = !!options.validateBeforeSave;
     } else {
-      shouldValidate = this.schema.options.validateBeforeSave;
+      shouldValidate = this.$__schema.options.validateBeforeSave;
     }
 
     // Validate
@@ -33,7 +33,7 @@ module.exports = function(schema) {
         { validateModifiedOnly: options.validateModifiedOnly } :
         null;
       this.validate(validateOptions, function(error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           _this.$op = 'save';
           next(error);
         });
diff --git a/test/document.test.js b/test/document.test.js
index efbf71d1692..d78abb7b840 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9850,16 +9850,58 @@ describe('document', function() {
       assert.ok(!_doc);
     });
   });
+
   it('handles paths named `schema` gh-8798', function() {
     const schema = new Schema({
       schema: String,
       name: String
     });
     const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = yield Test.create({ schema: 'test', name: 'test' });
+      yield doc.save();
+      assert.ok(doc);
+      assert.equal(doc.schema, 'test');
+      assert.equal(doc.name, 'test');
+
+      const fromDb = yield Test.findById(doc);
+      assert.equal(fromDb.schema, 'test');
+      assert.equal(fromDb.name, 'test');
+
+      doc.schema = 'test2';
+      yield doc.save();
+
+      yield fromDb.remove();
+      doc.name = 'test3';
+      const err = yield doc.save().then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.name, 'DocumentNotFoundError');
+    });
+  });
+
+  it('handles nested paths named `schema` gh-8798', function() {
+    const schema = new Schema({
+      nested: {
+        schema: String
+      },
+      name: String
+    });
+    const Test = db.model('Test', schema);
+
     return co(function*() {
-      const doc = yield Test.create({ schema: 'foo' }, { name: 'frank' });
+      const doc = yield Test.create({ nested: { schema: 'test' }, name: 'test' });
       yield doc.save();
       assert.ok(doc);
+      assert.equal(doc.nested.schema, 'test');
+      assert.equal(doc.name, 'test');
+
+      const fromDb = yield Test.findById(doc);
+      assert.equal(fromDb.nested.schema, 'test');
+      assert.equal(fromDb.name, 'test');
+
+      doc.nested.schema = 'test2';
+      yield doc.save();
     });
   });
 });

From 0c3f4d7bd49cc2e581a34cdfba3a035637933ec3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 26 Jan 2021 14:12:19 -0500
Subject: [PATCH 1650/2348] fix: allow using `schema` as a pathname

---
 lib/document.js                 | 4 ++--
 lib/plugins/removeSubdocs.js    | 2 +-
 lib/plugins/saveSubdocs.js      | 8 ++++----
 lib/plugins/trackTransaction.js | 4 ++--
 lib/types/core_array.js         | 4 ++--
 lib/types/subdocument.js        | 4 ++--
 test/document.unit.test.js      | 4 ++--
 test/schema.test.js             | 6 ------
 8 files changed, 15 insertions(+), 21 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 536ce4a6dfd..adaa85ca605 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3190,7 +3190,7 @@ Document.prototype.$toObject = function(options, json) {
 
   const path = json ? 'toJSON' : 'toObject';
   const baseOptions = get(this, 'constructor.base.options.' + path, {});
-  const schemaOptions = get(this, 'schema.options', {});
+  const schemaOptions = get(this, '$__schema.options', {});
   // merge base default options with Schema's set default options if available.
   // `clone` is necessary here because `utils.options` directly modifies the second input.
   defaultOptions = utils.options(defaultOptions, clone(baseOptions));
@@ -3277,7 +3277,7 @@ Document.prototype.$toObject = function(options, json) {
 
   // In the case where a subdocument has its own transform function, we need to
   // check and see if the parent has a transform (options.transform) and if the
-  // child schema has a transform (this.$__schema.options.toObject) In this case,
+  // child schema has a transform (this.schema.options.toObject) In this case,
   // we need to adjust options.transform to be the child schema's transform and
   // not the parent schema's
   if (transform) {
diff --git a/lib/plugins/removeSubdocs.js b/lib/plugins/removeSubdocs.js
index 44b2ea62790..8c3d5b3224d 100644
--- a/lib/plugins/removeSubdocs.js
+++ b/lib/plugins/removeSubdocs.js
@@ -21,7 +21,7 @@ module.exports = function(schema) {
       subdoc.$__remove(cb);
     }, function(error) {
       if (error) {
-        return _this.schema.s.hooks.execPost('remove:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('remove:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
diff --git a/lib/plugins/saveSubdocs.js b/lib/plugins/saveSubdocs.js
index c0a3144e778..12bbe9b2bfd 100644
--- a/lib/plugins/saveSubdocs.js
+++ b/lib/plugins/saveSubdocs.js
@@ -23,12 +23,12 @@ module.exports = function(schema) {
     }
 
     each(subdocs, function(subdoc, cb) {
-      subdoc.schema.s.hooks.execPre('save', subdoc, function(err) {
+      subdoc.$__schema.s.hooks.execPre('save', subdoc, function(err) {
         cb(err);
       });
     }, function(error) {
       if (error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
@@ -51,12 +51,12 @@ module.exports = function(schema) {
     }
 
     each(subdocs, function(subdoc, cb) {
-      subdoc.schema.s.hooks.execPost('save', subdoc, [subdoc], function(err) {
+      subdoc.$__schema.s.hooks.execPost('save', subdoc, [subdoc], function(err) {
         cb(err);
       });
     }, function(error) {
       if (error) {
-        return _this.schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
+        return _this.$__schema.s.hooks.execPost('save:error', _this, [_this], { error: error }, function(error) {
           next(error);
         });
       }
diff --git a/lib/plugins/trackTransaction.js b/lib/plugins/trackTransaction.js
index 410a596f3bc..30ded8785f2 100644
--- a/lib/plugins/trackTransaction.js
+++ b/lib/plugins/trackTransaction.js
@@ -18,8 +18,8 @@ module.exports = function trackTransaction(schema) {
       if (this.isNew) {
         initialState.isNew = true;
       }
-      if (this.schema.options.versionKey) {
-        initialState.versionKey = this.get(this.schema.options.versionKey);
+      if (this.$__schema.options.versionKey) {
+        initialState.versionKey = this.get(this.$__schema.options.versionKey);
       }
 
       initialState.modifiedPaths = new Set(Object.keys(this.$__.activePaths.states.modify));
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index df66617d451..5b456018924 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -248,8 +248,8 @@ class CoreMongooseArray extends Array {
 
       // gh-2399
       // we should cast model only when it's not a discriminator
-      const isDisc = value.schema && value.schema.discriminatorMapping &&
-          value.schema.discriminatorMapping.key !== undefined;
+      const isDisc = value.$__schema && value.$__schema.discriminatorMapping &&
+          value.$__schema.discriminatorMapping.key !== undefined;
       if (!isDisc) {
         value = new Model(value);
       }
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index 4e0976e4bf2..7a5df2d3ab4 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -25,9 +25,9 @@ function Subdocument(value, fields, parent, skipId, options) {
   let initedPaths = null;
   if (hasPriorDoc) {
     this._doc = Object.assign({}, options.priorDoc._doc);
-    delete this._doc[this.schema.options.discriminatorKey];
+    delete this._doc[this.$__schema.options.discriminatorKey];
     initedPaths = Object.keys(options.priorDoc._doc || {}).
-      filter(key => key !== this.schema.options.discriminatorKey);
+      filter(key => key !== this.$__schema.options.discriminatorKey);
   }
   if (parent != null) {
     // If setting a nested path, should copy isNew from parent re: gh-7048
diff --git a/test/document.unit.test.js b/test/document.unit.test.js
index bc7fbd3bc50..0ebdc16dc1b 100644
--- a/test/document.unit.test.js
+++ b/test/document.unit.test.js
@@ -19,7 +19,7 @@ describe('sharding', function() {
       }
     };
     const Stub = function() {
-      this.schema = mockSchema;
+      this.$__schema = mockSchema;
       this.$__ = {};
     };
     Stub.prototype.__proto__ = mongoose.Document.prototype;
@@ -37,7 +37,7 @@ describe('toObject()', function() {
 
   beforeEach(function() {
     Stub = function() {
-      const schema = this.schema = {
+      const schema = this.$__schema = {
         options: { toObject: { minimize: false, virtuals: true } },
         virtuals: { virtual: 'test' }
       };
diff --git a/test/schema.test.js b/test/schema.test.js
index 2dbe512425a..32ccf64a746 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1436,12 +1436,6 @@ describe('schema', function() {
         });
       }, /`collection` may not be used as a schema pathname/);
 
-      assert.throws(function() {
-        new Schema({
-          schema: String
-        });
-      }, /`schema` may not be used as a schema pathname/);
-
       assert.throws(function() {
         new Schema({
           isNew: String

From 08bdecd1f76b92ddd507a986edde5a41523829a1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 26 Jan 2021 17:58:51 -0500
Subject: [PATCH 1651/2348] fix: no more phantom arrays

---
 .../populate/getModelsMapForPopulate.js       | 10 ++---
 lib/helpers/populate/getSchemaTypes.js        |  9 +---
 lib/model.js                                  |  6 +--
 test/model.populate.test.js                   | 42 +++++++++++++++++++
 4 files changed, 49 insertions(+), 18 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index a5bd38821be..7d26093fe52 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -43,7 +43,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
   for (i = 0; i < len; i++) {
     doc = docs[i];
     let justOne = null;
-
     schema = getSchemaTypes(modelSchema, doc, options.path);
     // Special case: populating a path that's a DocumentArray unless
     // there's an explicit `ref` or `refPath` re: gh-8946
@@ -174,9 +173,11 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       }
     } else if (schema && !schema[schemaMixedSymbol]) {
       // Skip Mixed types because we explicitly don't do casting on those.
-      justOne = Array.isArray(schema) ?
-        schema.every(schema => !schema.$isMongooseArray) :
-        !schema.$isMongooseArray;
+      if (options.path.endsWith('.' + schema.path)) {
+        justOne = Array.isArray(schema) ?
+          schema.every(schema => !schema.$isMongooseArray) :
+          !schema.$isMongooseArray;
+      }
     }
 
     if (!modelNames) {
@@ -358,7 +359,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       }
     }
   }
-
   return map;
 
   function _getModelNames(doc, schema) {
diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index 15660df1f78..a6ee3a1586a 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -20,7 +20,6 @@ const populateModelSymbol = require('../symbols').populateModelSymbol;
 module.exports = function getSchemaTypes(schema, doc, path) {
   const pathschema = schema.path(path);
   const topLevelDoc = doc;
-
   if (pathschema) {
     return pathschema;
   }
@@ -32,8 +31,6 @@ module.exports = function getSchemaTypes(schema, doc, path) {
 
     while (p--) {
       trypath = parts.slice(0, p).join('.');
-      foundschema = schema.path(trypath);
-
       if (foundschema == null) {
         continue;
       }
@@ -117,7 +114,6 @@ module.exports = function getSchemaTypes(schema, doc, path) {
               ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
                 !foundschema.schema.$isSingleNested;
             }
-
             return ret;
           }
         } else if (p !== parts.length &&
@@ -153,7 +149,6 @@ module.exports = function getSchemaTypes(schema, doc, path) {
             ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
               !model.schema.$isSingleNested;
           }
-
           return ret;
         }
       }
@@ -163,6 +158,7 @@ module.exports = function getSchemaTypes(schema, doc, path) {
         const model = Array.isArray(_val) && _val.length > 0 ?
           leanPopulateMap.get(_val[0]) :
           leanPopulateMap.get(_val);
+        console.log(model);
         // Populated using lean, `leanPopulateMap` value is the foreign model
         const schema = model != null ? model.schema : null;
         if (schema != null) {
@@ -177,15 +173,12 @@ module.exports = function getSchemaTypes(schema, doc, path) {
             ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
               !schema.$isSingleNested;
           }
-
           return ret;
         }
       }
-
       return foundschema;
     }
   }
-
   // look for arrays
   const parts = path.split('.');
   for (let i = 0; i < parts.length; ++i) {
diff --git a/lib/model.js b/lib/model.js
index d7df3360d0e..36cd5ad2f67 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4336,10 +4336,9 @@ function populate(model, docs, options, callback) {
   }
 
   const modelsMap = getModelsMapForPopulate(model, docs, options);
-
   if (modelsMap instanceof MongooseError) {
     return immediate(function() {
-      callback(modelsMap);
+      callback(modelsMap.options._docs);
     });
   }
 
@@ -4420,7 +4419,6 @@ function populate(model, docs, options, callback) {
     } else if (mod.options.limit != null) {
       assignmentOpts.originalLimit = mod.options.limit;
     }
-
     params.push([mod, match, select, assignmentOpts, _next]);
   }
 
@@ -4439,7 +4437,6 @@ function populate(model, docs, options, callback) {
   for (const arr of params) {
     _execPopulateQuery.apply(null, arr);
   }
-
   function _next(err, valsFromDb) {
     if (err != null) {
       return callback(err, null);
@@ -4473,7 +4470,6 @@ function populate(model, docs, options, callback) {
 
 function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
   const subPopulate = utils.clone(mod.options.populate);
-
   const queryOptions = Object.assign({
     skip: mod.options.skip,
     limit: mod.options.limit,
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 4e93ee4984c..a3f4716a899 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9869,4 +9869,46 @@ describe('model: populate:', function() {
       assert.deepEqual(findCallOptions[0].virtuals, ['foo']);
     });
   });
+  it('gh-9833', function() {
+    const util = require('util');
+    const Books = db.model('books', new Schema({ name: String, tags: [{ type: Schema.Types.ObjectId, ref: 'tags' }] }));
+    const Tags = db.model('tags', new Schema({ author: Schema.Types.ObjectId }));
+    const Authors = db.model('authors', new Schema({ name: String }));
+
+    return co(function*() {
+      const anAuthor = new Authors({ name: 'Author1' });
+      yield anAuthor.save();
+
+      const aTag = new Tags({ author: anAuthor.id });
+      yield aTag.save();
+
+      const aBook = new Books({ name: 'Book1', tags: [aTag.id] });
+      yield aBook.save();
+
+      const aggregateOptions = [
+        { $match: {
+          name: { $in: [aBook.name] }
+        } },
+        { $lookup: {
+          from: 'tags',
+          localField: 'tags',
+          foreignField: '_id',
+          as: 'tags'
+        } }
+      ];
+      const books = yield Books.aggregate(aggregateOptions).exec();
+
+      console.log('books = ' + util.inspect(books, false, null, true));
+
+      const populateOptions = [{
+        path: 'tags.author',
+        model: 'authors',
+        select: '_id name'
+      }];
+
+      const populatedBooks = yield Books.populate(books, populateOptions);
+      console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true));
+      assert.ok(!Array.isArray(populatedBooks[0].tags[0].author))
+    });
+  });
 });

From 9e8937cb7dc1c8ff5c9bfcd77d4fbd61b7fffce1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 26 Jan 2021 18:01:34 -0500
Subject: [PATCH 1652/2348] added the semicolon

---
 test/model.populate.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a3f4716a899..def9145cde2 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9908,7 +9908,7 @@ describe('model: populate:', function() {
 
       const populatedBooks = yield Books.populate(books, populateOptions);
       console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true));
-      assert.ok(!Array.isArray(populatedBooks[0].tags[0].author))
+      assert.ok(!Array.isArray(populatedBooks[0].tags[0].author));
     });
   });
 });

From 189191cfdcc1342925d140267479f9b27ddb802b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 26 Jan 2021 18:11:01 -0500
Subject: [PATCH 1653/2348] reverted deletions

---
 lib/helpers/populate/getSchemaTypes.js | 2 +-
 lib/model.js                           | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index a6ee3a1586a..7626e2a4b84 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -31,6 +31,7 @@ module.exports = function getSchemaTypes(schema, doc, path) {
 
     while (p--) {
       trypath = parts.slice(0, p).join('.');
+      foundschema = schema.path(trypath);
       if (foundschema == null) {
         continue;
       }
@@ -158,7 +159,6 @@ module.exports = function getSchemaTypes(schema, doc, path) {
         const model = Array.isArray(_val) && _val.length > 0 ?
           leanPopulateMap.get(_val[0]) :
           leanPopulateMap.get(_val);
-        console.log(model);
         // Populated using lean, `leanPopulateMap` value is the foreign model
         const schema = model != null ? model.schema : null;
         if (schema != null) {
diff --git a/lib/model.js b/lib/model.js
index 36cd5ad2f67..a4ec8e43eb6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4338,7 +4338,7 @@ function populate(model, docs, options, callback) {
   const modelsMap = getModelsMapForPopulate(model, docs, options);
   if (modelsMap instanceof MongooseError) {
     return immediate(function() {
-      callback(modelsMap.options._docs);
+      callback(modelsMap);
     });
   }
 

From 5a999819cc60811996b0bcf4e84046249a8ba8c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 28 Jan 2021 17:37:34 -0500
Subject: [PATCH 1654/2348] chore: release 5.11.14

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index e3f40f5caf3..2e1d6500294 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.11.14 / 2021-01-28
+====================
+ * fix(populate): avoid inferring `justOne` from parent when populating a POJO with a manually populated path #9833 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(document): apply setters on each element of the array when setting a populated array #9838
+ * fix(map): handle change tracking on maps of subdocs #9811 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(document): remove dependency on `documentIsSelected` symbol #9841 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(error): make ValidationError.toJSON to include the error name correctly #9849 [hanzki](https://github.com/hanzki)
+ * fix(index.d.ts): indicate that `Document#remove()` returns a promise, not a query #9826
+ * fix(index.d.ts): allow setting `SchemaType#enum` to TypeScript enum with `required: true` #9546
+
 5.11.13 / 2021-01-20
 ====================
  * fix(map): handle change tracking on map of arrays #9813
diff --git a/package.json b/package.json
index 98aafadf2c0..64ef253ecd8 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.13",
+  "version": "5.11.14",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From a88fc3c1d502cb88005fd3773c386048f43b5bfd Mon Sep 17 00:00:00 2001
From: Jonathan Mataloni <jo.mataloni@gmail.com>
Date: Fri, 29 Jan 2021 12:09:33 +0100
Subject: [PATCH 1655/2348] Add missing overload to Model.validate (#9877)

---
 index.d.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/index.d.ts b/index.d.ts
index 3d969ff6206..e20588cfd37 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -753,6 +753,7 @@ declare module 'mongoose' {
     /** Casts and validates the given object against this model's schema, passing the given `context` to custom validators. */
     validate(callback?: (err: any) => void): Promise<void>;
     validate(optional: any, callback?: (err: any) => void): Promise<void>;
+    validate(optional: any, pathsToValidate: string[], callback?: (err: any) => void): Promise<void>;
 
     /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
     watch(pipeline?: Array<Record<string, unknown>>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;

From e798139f067924d023561f061b4a976d4200318a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Feb 2021 10:32:32 -0500
Subject: [PATCH 1656/2348] fix(index.d.ts): support calling `Schema#pre()` and
 `Schema#post()` with options and array of hooked function names

Fix #9844
---
 index.d.ts                    | 28 ++++++++++++++++++++++------
 test/typescript/middleware.ts |  4 ++++
 2 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3d969ff6206..beda329b82a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1037,8 +1037,12 @@ declare module 'mongoose' {
     useProjection?: boolean;
   }
 
+  type MongooseDocumentMiddleware = 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init';
   type MongooseQueryMiddleware = 'count' | 'deleteMany' | 'deleteOne' | 'find' | 'findOne' | 'findOneAndDelete' | 'findOneAndRemove' | 'findOneAndUpdate' | 'remove' | 'update' | 'updateOne' | 'updateMany';
 
+  type SchemaPreOptions = { document?: boolean, query?: boolean };
+  type SchemaPostOptions = { document?: boolean, query?: boolean };
+
   class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>> extends events.EventEmitter {
     /**
      * Create a new schema
@@ -1113,21 +1117,33 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = DocType>(method: 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init' | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
-    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: any;
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index 5c941ea887a..7a89a3e34c0 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -18,6 +18,10 @@ schema.post<Aggregate<any>>('aggregate', async function(res: Array<any>) {
   console.log('Pipeline', this.pipeline(), res[0]);
 });
 
+schema.pre(['save', 'validate'], { query: false, document: true }, async function applyChanges() {
+  await Test.findOne({});
+});
+
 interface ITest extends Document {
   name?: string;
 }

From 3439515059735877dc0a1e27ed46db2d9371ff8b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Feb 2021 10:50:38 -0500
Subject: [PATCH 1657/2348] fix(index.d.ts): make `Query` a class, allow
 calling `Query#where()` with object argument and with no arguments

Fix #9856
---
 index.d.ts                 |  6 +++++-
 test/typescript/queries.ts | 13 +++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index beda329b82a..044c0d1545e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -844,6 +844,8 @@ declare module 'mongoose' {
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): Query<Array<T>, T>;
+    where(obj: object): Query<Array<T>, T>;
+    where(): Query<Array<T>, T>;
   }
 
   interface QueryOptions {
@@ -1785,7 +1787,7 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false };
 
-  interface Query<ResultType, DocType extends Document> {
+  class Query<ResultType, DocType extends Document> {
     _mongooseOptions: MongooseQueryOptions;
 
     /** Executes the query */
@@ -2163,6 +2165,8 @@ declare module 'mongoose' {
 
     /** Specifies a path for use with chaining. */
     where(path: string, val?: any): this;
+    where(obj: object): this;
+    where(): this;
 
     /** Defines a `$within` or `$geoWithin` argument for geo-spatial queries. */
     within(val?: any): this;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 699742dd757..54807420698 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document, Types } from 'mongoose';
+import { Schema, model, Document, Types, Query } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' }, tags: [String] });
 
@@ -13,9 +13,11 @@ const Test = model<ITest>('Test', schema);
 
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
 
+// ObjectId casting
 Test.find({ parent: new Types.ObjectId('0'.repeat(24)) });
 Test.find({ parent: '0'.repeat(24) });
 
+// Operators
 Test.find({ name: { $in: ['Test'] } }).exec().then((res: Array<ITest>) => console.log(res));
 
 Test.find({ name: 'test' }, (err: Error, docs: ITest[]) => {
@@ -45,4 +47,11 @@ Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { new: true, upsert:
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
 
 Test.findOneAndUpdate({ name: 'test' }, { $addToSet: { tags: 'each' } });
-Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
\ No newline at end of file
+Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
+
+const query: Query<ITest | null, ITest> = Test.findOne();
+query instanceof Query;
+
+// Chaining
+Test.findOne().where({ name: 'test' });
+Test.where().find({ name: 'test' });
\ No newline at end of file

From bdbf25d137ad3a715adf973e919be4897eeec445 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Feb 2021 12:22:00 -0500
Subject: [PATCH 1658/2348] fix(index.d.ts): better support for
 `SchemaDefinition` generics when creating schema

Fix #9862
Fix #9863
Re: #9789
---
 index.d.ts                | 12 ++++++------
 test/typescript/schema.ts | 26 +++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 97a2f1da50c..d3651427e34 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1045,14 +1045,14 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefModel = undefined> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
-    constructor(definition?: SchemaDefinition<SchemaDefModel>, options?: SchemaOptions);
+    constructor(definition?: SchemaDefinition<DocumentDefinition<SchemaDefinitionType>>, options?: SchemaOptions);
 
     /** Adds key path / schema type pairs to this schema. */
-    add(obj: SchemaDefinition<SchemaDefModel> | Schema, prefix?: string): this;
+    add(obj: SchemaDefinition<DocumentDefinition<SchemaDefinitionType>> | Schema, prefix?: string): this;
 
     /**
      * Array of child schemas (from document arrays and single nested subdocs)
@@ -1184,8 +1184,8 @@ declare module 'mongoose' {
   type SchemaDefinitionProperty<T = undefined> = SchemaTypeOptions<T extends undefined ? any : T> |
     Function |
     string |
-    Schema |
-    Schema[] |
+    Schema<T extends Document ? T : Document<any>> |
+    Schema<T extends Document ? T : Document<any>>[] |
     SchemaTypeOptions<T extends undefined ? any : T>[] |
     Function[] |
     SchemaDefinition<T> |
@@ -1193,7 +1193,7 @@ declare module 'mongoose' {
 
   type SchemaDefinition<T = undefined> = T extends undefined
     ? { [path: string]: SchemaDefinitionProperty; }
-    : { [path in keyof T]-?: SchemaDefinitionProperty<T[path]>; };
+    : { [path in keyof T]?: SchemaDefinitionProperty<T[path]>; };
 
   interface SchemaOptions {
     /**
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 79348e2ba29..e024b4718ab 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -1,4 +1,4 @@
-import { Schema } from 'mongoose';
+import { Schema, Document, SchemaDefinition, SchemaDefinitionProperty, Model } from 'mongoose';
 
 enum Genre {
   Action,
@@ -25,3 +25,27 @@ const movieSchema: Schema = new Schema({
     required: true
   }
 });
+
+// Using `SchemaDefinition`
+interface IProfile { age: number; }
+interface ProfileDoc extends Document, IProfile {}
+const ProfileSchemaDef: SchemaDefinition<IProfile> = { age: Number };
+export const ProfileSchema = new Schema<ProfileDoc, Model<ProfileDoc>, ProfileDoc>(ProfileSchemaDef);
+
+interface IUser {
+  email: string;
+  profile: ProfileDoc;
+}
+
+interface UserDoc extends Document, IUser {}
+
+const ProfileSchemaDef2: SchemaDefinition<IProfile> = {
+  age: Schema.Types.Number
+};
+
+const ProfileSchema2: Schema<ProfileDoc, Model<ProfileDoc>> = new Schema<ProfileDoc>(ProfileSchemaDef2);
+
+const UserSchemaDef: SchemaDefinition<IUser> = {
+  email: String,
+  profile: ProfileSchema2
+};
\ No newline at end of file

From 452f5521ef3ac53d674a16b48abcd214b307681c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Feb 2021 14:37:26 -0500
Subject: [PATCH 1659/2348] docs(connections): clarify that Mongoose can emit
 'error' both during initial connection and after initial connection

Fix #9853
---
 docs/connections.pug | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/docs/connections.pug b/docs/connections.pug
index 64bc912c49b..4a9962b4cd1 100644
--- a/docs/connections.pug
+++ b/docs/connections.pug
@@ -118,7 +118,7 @@ block content
 
     There are two classes of errors that can occur with a Mongoose connection.
 
-    - Error on initial connection. If initial connection fails, Mongoose will **not** attempt to reconnect, it will emit an 'error' event, and the promise `mongoose.connect()` returns will reject.
+    - Error on initial connection. If initial connection fails, Mongoose will emit an 'error' event and the promise `mongoose.connect()` returns will reject. However, Mongoose will **not** automatically try to reconnect.
     - Error after initial connection was established. Mongoose will attempt to reconnect, and it will emit an 'error' event.
 
     To handle initial connection errors, you should use `.catch()` or `try/catch` with async/await.
@@ -145,9 +145,8 @@ block content
     });
     ```
 
-    Note that the `error` event in the code above does not fire when mongoose loses 
-    connection after the initial connection was established. You can listen to the
-    `disconnected` event for that purpose.
+    Note that Mongoose does not necessarily emit an 'error' event if it loses connectivity to MongoDB. You should
+    listen to the `disconnected` event to report when Mongoose is disconnected from MongoDB.
 
     <h3 id="options"><a href="#options">Options</a></h3>
 

From 968bd8a57d735f97a2cf1686ba1efc8bf23593d4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Feb 2021 16:13:49 -0500
Subject: [PATCH 1660/2348] fix(index.d.ts): throw compiler error if schema
 says path is a String, but interface says path is a number

Fix #9857
---
 index.d.ts                   | 12 +++++++++---
 test/typescript/main.test.js |  4 +++-
 test/typescript/schema.ts    | 22 +++++++++++++++++++++-
 3 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index d3651427e34..8706df16808 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1181,9 +1181,15 @@ declare module 'mongoose' {
     virtualpath(name: string): VirtualType | null;
   }
 
+  type SchemaDefinitionWithBuiltInClass<T> = T extends number
+    ? (typeof Number | 'number' | 'Number')
+    : T extends string
+    ? (typeof String | 'string' | 'String')
+    : (Function | string);
+
   type SchemaDefinitionProperty<T = undefined> = SchemaTypeOptions<T extends undefined ? any : T> |
-    Function |
-    string |
+    SchemaDefinitionWithBuiltInClass<T> |
+    typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |
     Schema<T extends Document ? T : Document<any>>[] |
     SchemaTypeOptions<T extends undefined ? any : T>[] |
@@ -1358,7 +1364,7 @@ declare module 'mongoose' {
   }
 
   interface SchemaTypeOptions<T> {
-    type?: T;
+    type: T;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index fc9d2f06f46..2d6b1188074 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -178,7 +178,9 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 0);
+    assert.equal(errors.length, 1);
+    const messageText = errors[0].messageText.messageText;
+    assert.ok(/Type 'StringConstructor' is not assignable to type.*number/.test(messageText), messageText);
   });
 
   it('document', function() {
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index e024b4718ab..c6f61667b95 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -48,4 +48,24 @@ const ProfileSchema2: Schema<ProfileDoc, Model<ProfileDoc>> = new Schema<Profile
 const UserSchemaDef: SchemaDefinition<IUser> = {
   email: String,
   profile: ProfileSchema2
-};
\ No newline at end of file
+};
+
+async function gh9857() {
+  interface User {
+    name: number;
+    active: boolean;
+    points: number;
+  }
+
+  type UserDocument = Document<User>;
+  type UserSchemaDefinition = SchemaDefinition<User>;
+  type UserModel = Model<UserDocument>;
+
+  const schemaDefinition: UserSchemaDefinition = {
+    name: String,
+    active: Boolean,
+    points: Number
+  };
+
+  const schema = new Schema<UserDocument, UserModel, User>(schemaDefinition);
+}
\ No newline at end of file

From 07b227f4c71ab9940f98462e1cbf312fd9b9dc6e Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 1 Feb 2021 17:03:10 -0500
Subject: [PATCH 1661/2348] actually updated all the isSelected to
 $__isSelected

sorry again
---
 lib/document.js                           | 12 ++---
 lib/helpers/timestamps/setupTimestamps.js |  2 +-
 lib/model.js                              |  2 +-
 lib/types/embedded.js                     |  2 +-
 test/document.test.js                     | 57 +++++++++++++++++++++++
 5 files changed, 66 insertions(+), 9 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index cb5317c72f8..7bf725fdeef 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -664,7 +664,7 @@ function init(self, obj, doc, opts, prefix) {
     // Should still work if not a model-level discriminator, but should not be
     // necessary. This is *only* to catch the case where we queried using the
     // base model and the discriminated model has a projection
-    if (self.schema.$isRootDiscriminator && !self.isSelected(path)) {
+    if (self.schema.$isRootDiscriminator && !self.$__isSelected(path)) {
       return;
     }
 
@@ -1139,7 +1139,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
       // traverse the element ({nested: null})` is not likely. If user gets
       // that error, its their fault for now. We should reconsider disallowing
       // modifying not selected paths for 6.x
-      if (!this.isSelected(curPath)) {
+      if (!this.$__isSelected(curPath)) {
         this.unmarkModified(curPath);
       }
       cur = this.$__getValue(curPath);
@@ -1420,7 +1420,7 @@ Document.prototype.$__shouldModify = function(pathToMark, path, constructing, pa
     return false;
   }
 
-  if (val === void 0 && !this.isSelected(path)) {
+  if (val === void 0 && !this.$__isSelected(path)) {
     // when a path is not selected in a query, its initial
     // value will be undefined.
     return true;
@@ -2061,7 +2061,7 @@ Document.prototype.isSelected = function isSelected(path) {
     path = path.split(' ');
   }
   if (Array.isArray(path)) {
-    return path.some(p => this.isSelected(p));
+    return path.some(p => this.$__isSelected(p));
   }
 
   const paths = Object.keys(this.$__.selected);
@@ -2259,7 +2259,7 @@ function _getPathsToValidate(doc) {
 
   // only validate required fields when necessary
   let paths = new Set(Object.keys(doc.$__.activePaths.states.require).filter(function(path) {
-    if (!doc.isSelected(path) && !doc.isModified(path)) {
+    if (!doc.$__isSelected(path) && !doc.isModified(path)) {
       return false;
     }
     if (path in doc.$__.cachedRequired) {
@@ -3568,7 +3568,7 @@ function applyGetters(self, json, options) {
     let part;
     cur = self._doc;
 
-    if (!self.isSelected(path)) {
+    if (!self.$__isSelected(path)) {
       continue;
     }
 
diff --git a/lib/helpers/timestamps/setupTimestamps.js b/lib/helpers/timestamps/setupTimestamps.js
index 752a565738c..76140099df8 100644
--- a/lib/helpers/timestamps/setupTimestamps.js
+++ b/lib/helpers/timestamps/setupTimestamps.js
@@ -51,7 +51,7 @@ module.exports = function setupTimestamps(schema, timestamps) {
       (this.ownerDocument ? this.ownerDocument() : this).constructor.base.now();
     const auto_id = this._id && this._id.auto;
 
-    if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.isSelected(createdAt)) {
+    if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.$__isSelected(createdAt)) {
       this.$set(createdAt, auto_id ? this._id.getTimestamp() : defaultTimestamp);
     }
 
diff --git a/lib/model.js b/lib/model.js
index a4ec8e43eb6..04cb57a31c4 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -823,7 +823,7 @@ Model.prototype.$__version = function(where, delta) {
   // there is no way to select the correct version. we could fail
   // fast here and force them to include the versionKey but
   // thats a bit intrusive. can we do this automatically?
-  if (!this.isSelected(key)) {
+  if (!this.$__isSelected(key)) {
     return;
   }
 
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 7f582727001..531128d404b 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -106,7 +106,7 @@ EmbeddedDocument.prototype.markModified = function(path) {
   }
 
   const pathToCheck = this.__parentArray.$path() + '.0.' + path;
-  if (this.isNew && this.ownerDocument().isSelected(pathToCheck)) {
+  if (this.isNew && this.ownerDocument().$__isSelected(pathToCheck)) {
     // Mark the WHOLE parent array as modified
     // if this is a new document (i.e., we are initializing
     // a document),
diff --git a/test/document.test.js b/test/document.test.js
index 90b1f718fe3..ed03216f041 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9878,4 +9878,61 @@ describe('document', function() {
       assert.equal(ss.nested[0].toHexString(), updatedElID);
     });
   });
+  it('gh9884', function() {
+    // mongoose.set('useFindAndModify', false);
+    // run().catch(err => console.log(err));
+
+    return co(function*() {
+
+      const obi = new Schema({
+        eType: {
+          type: String,
+          required: true,
+          uppercase: true
+        },
+        eOrigin: {
+          type: String,
+          required: true
+        },
+        eIds: [
+          {
+            type: String
+          }
+        ]
+      }, { _id: false });
+
+      const schema = new Schema({
+        name: String,
+        description: String,
+        isSelected: {
+          type: Boolean,
+          default: false
+        },
+        wan: {
+          type: [obi],
+          default: undefined,
+          required: true
+        }
+      });
+
+      const newDoc = {
+        name: 'name',
+        description: 'new desc',
+        isSelected: true,
+        wan: [
+          {
+            eType: 'X',
+            eOrigin: 'Y',
+            eIds: ['Y', 'Z']
+          }
+        ]
+      };
+
+      const Model = db.model('Test', schema);
+      console.log('Here');
+      yield Model.create(newDoc);
+
+      console.log('Done', yield Model.findOne(), new Date());
+    });
+  });
 });

From 40b2b406a58922d25e3035b48b8337b415597103 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 1 Feb 2021 17:39:50 -0500
Subject: [PATCH 1662/2348] fix: replaced isSelected with $__isSelected

---
 test/document.test.js | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index ed03216f041..a96e19111e9 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9879,9 +9879,6 @@ describe('document', function() {
     });
   });
   it('gh9884', function() {
-    // mongoose.set('useFindAndModify', false);
-    // run().catch(err => console.log(err));
-
     return co(function*() {
 
       const obi = new Schema({
@@ -9929,10 +9926,9 @@ describe('document', function() {
       };
 
       const Model = db.model('Test', schema);
-      console.log('Here');
       yield Model.create(newDoc);
-
-      console.log('Done', yield Model.findOne(), new Date());
+      const doc = yield Model.findOne();
+      assert.ok(doc);
     });
   });
 });

From 71e6b58dd3455ef5c6fe701d1fb63acca389f671 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Feb 2021 17:59:17 -0500
Subject: [PATCH 1663/2348] chore: update opencollective sponsors

---
 docs/images/fortunegames.jpg | Bin 0 -> 21055 bytes
 index.pug                    |   4 ++--
 2 files changed, 2 insertions(+), 2 deletions(-)
 create mode 100644 docs/images/fortunegames.jpg

diff --git a/docs/images/fortunegames.jpg b/docs/images/fortunegames.jpg
new file mode 100644
index 0000000000000000000000000000000000000000..795eca76cf2986f856351fd5d1aac6bf1b6d1bf8
GIT binary patch
literal 21055
zcma&N1z1#D_dk9Jm5>&YkdP9FknRwW7El<5MmnXtQ9`6aI;CL<hi+85rKP32VQBb|
z-s{!-{@&;Reb+qCIs43BYwvYFd+oK?j&t+v<~x8ZCnYNdARz$&65<EkOacA?+U?tD
zx6yvmoxiSk?%ct;gGl3H6X4@v<KhzDe@I41L`95?`+)ZW6)oMPM~?`|SlF5AA3tPx
zM301yj*f+iMTmt(NKZ&eNdLbO#}6ispFeu~n@<298nOzq3JMY)fQ*NPf`@d|3XuO$
z@zxJj{~;t~6x7>yZlNJ^pW^~ZsEB8jJ7{-qq29(s@chWVbsO&vJ~hEZ_In&p#Gk*g
zqoI{h(KoPvO~}b*=ob|&sp^nfM)v`>M@0W7=JOZsr(mP^S>=O63kQfINfC9SApJ*$
zs3^B?Bl4*6e&qek{>6cWjE90s&5lp-<laM$n@Qj<A|LS=9v}+re*Z`1|45($w}1Xa
zi`MG<A6ftNBl0~=f{Aza;DgT2gfupfGvsoU<hX^B<W}qPxmQ7%+da?2Ka#I(E3Q&9
z@+N`|nY-sCmQyRgG>@)`MvPr4NcyyY70vG#nOfPMU%V#ryV8x-6;W}|d%sZBIw!y2
zVS4BI)%|`}^OOi_ZB6SNU`}J=*1~pwu6UKW$WZayEp|^zf=PJ5LT@Q<S;qgY^uHJ}
zwChobnAP7E*~FQX+_O?Nr;WNSwv>@tjNa(yQOhkY_BXWdx!S)0%DMQpvcgx6b+trk
z<|6Bb<7(X+($k|Gd{D&}d0f{Ad9YO&Z~K0IBW5AGf4dx3>+vlZUz3;t%H*YT5$&n+
zS$vQcmVG+KtQcP9PGNHD9T{5wR6tOXmjS|p!aSTL_*nFddV2qmj*CV*GLal=Hr2n>
z{GT3fF%_b_)`dJD8g`<zJ_<9`O#OCcPENjZdRDK#e}@KYq6V5#d(GCRqJQ^fZ3HE5
z4KD)#&;US~+Q{nzSy+tprciif+4xx0&<NPZMn1ik+EjDqXeDvvedSYno!qN$jT9Yc
z`!!sxji1&ceg7ww{$xT^7J4R|U$CC^LZ@asp+AauEb4j#H>c>#0c=rUS9Z9q=@HGg
zHF|atS;48Pi)#nq{w+=MKp6}AWRs*K{Au)VBY$jhBgx}kd69gmwcy7N17aQ-6GPhI
z^-b=!Bm)gv=Ey(m{J+zv0C1bT$L@KcJZB?J0`mcFndqpc*qNTLCF61UlY^bLHHqGC
zJFhv<K-qFIwhEOhAoi=!BLehbmlCuMmuaX7Mazj7_iV`xpsJA@y@e(rp7D$8|GrZJ
z_X@X1pA_5hm)N@7L6@ryWXZ157@QApfQR>zE66V0vpYcMi>4pbg1T=21`H)gWP@iX
zTOb9_qFJmDRG^e%YToqT5ge}a=DhkY1K|<ec%AtD8FR>y^ZBjCEV)I+GM%i?BQaS~
zWpke1p9{6J-fhFwY=)j>i2YWMM+YUz8AmvxysyHN#-RL~phxh9o+h`8r1B{EiMh;g
z#{d5m>Lc6?*Rw0>h+(I(zOxBTVXWh9+ZSWD!uoB!xlRLbC<j9GcFW<3C;@f+!_({9
zr5>p?GYcmtbJW<PjnZOoKKTPYGXi0nbZidUE}S!yY)$)xy%{vXOZ?yU(u3K%JJ{E@
zV+l*HqkGi!^v#oRfb4xP7I%|kg7ni`iC4NcnlFCxhkdd}v8AzP@cIOZ(f%&sM+yyD
z?8ogFQDNw8qxL9`oo}Q?7SF2nc^jSOC>7b-CpTI2Z;+iw4^1}f4+(pIyOQ}vQu@j*
z)r-2H4i!NDCH~i420*Hse|(-EpcXe4+g9sdTNKBAjn5Z1`|7KJoEU;T0JUF;c?a5N
z-g$PwlZbx~bA!{K(ul_llaF(Dyro$+VSTf8LHiNW%GCYt6+J0NBXFI1+G4P<+7s;g
zes`hcg}@@6QTv@6pe8iHr=s+8TcZlHOGyXMoEFNHtDG`JzTM~$qvnXfA&=3yrKQpb
zS}S)#CVki{9G;yE=sACL3aS3aEUh0*`+`GF@bi|BphRxz2S(suedgc5;G$aJh7~(`
z>CilZ(>v%1rA}5}!{+-B&MaBtt5YgjdddVemh|-2rgk!n8WU(4kElLH{_Y|_VL?Z@
z7^KJNHg8Jo*ELi6rp!&J&Z4LKzM^Dj0|2vnYHXHgS!0wmse>%dm6~50_W%hYksRNH
z#tD12Jtbe$%4zHEDc%)F_?E1R>1hw>Y?fr(`2B?(6AH4DtfKD`?pyI=%%}T1FP#Dn
z6=gb}S3Z;qxe$t2c_-cv8=S7NA=*E?maA^kcT@SI#39~4TA#z+xszX?8M#%2(Cjyf
z{b6DN;2TFIb$P#gSgUNM?Ji!OhVBgjF2+z;ToyJjw6f?;iCc0QDs$jT(cP3WS{E26
z*v3|l{$18TDb$ef8jsII{67{6K**Ylr|NHjgzpn-2M_RpyOwH(1q3UJ+u?k}E{$GT
zXvv1FBDDMTucSe1hO=vSQKifghBtuu-SM^6TiQQjBmf<trJXaL5nyZjB;fpJp)!TE
zEDhXWDGRA*I@^mL)N1n0a&MAD+Zv6Ek>KRdjEz_^eAD=<sC5tXPviIf^8raNpStCA
z3JQKegi(GqVXxi1{L*xtZ=o4KbSgvazxDeVV?E@qpmBkRWka6~7F0JTqnNH=PN=m$
zz`w<+<NJO3<#>nz<a@sC!Lu7+2nR9Nlt(xo@qV~FObYyT>5%|FK$Y0Oo>6&ROlKS=
z+@DPH@UqBeU#SwMlKI?{B&syF7^|*~N8L26#3+<`tQR@sA2^YKKQuxDUK*F-Eiz72
zKiujbY=U^J?cA$aT)Nx;!m4ePcU5PpoF?az#U*K|s45QE{+}}bNFZ_awT?J#j%=2<
zn`efcr*>;tv}|cc=D1P^G~r2g4xe)INYJuAB8A``8*)|ALtxwTF?q&dfBD$0Gkc9W
zp@?XRfGiz^A7LDBtsIk1Vt;uZ06-Q4uzc537{*yYYguzlhaX^qdI;u@UPKSdi-a0R
zZO;hZ<7(ab_}=%IGN?#Yzmfoe`iQ(EOv9<;dvq2dzINz#&~;zxF}ASrVSEOZ-tRZx
z?-Z(E!(Ke`x%`VUmxAZviOZ=4IQh8T;^I9j-JOP>5jqL&hfMw&2i3U8DwT=`<_X*D
zV=I9L_#H!iGC_~vx3V#Of0l(ThVY9Gh2hdxOM7mZl1<6;iUm4P1C1O6R~@hA3^dOs
zzM?z*_7;Ek7%B|NaP>!=^wWJOqb|dZhexlW%Xb^e6QKTohRr`~L0r&*fIYN67i<&*
zco0pLz1zSmv!+`~ZW5Il=Kg#P+C8BHIku-2A5hL->8&*#+1{au^IR=s2=X;fL{t95
zyPzzfIkIA}%!Ch=LF1QpIm^7S$>Pkin-Y|OVRW&7&_({OGNK!a`yEP?&NUT!cwuD$
z#%rqq8sC4Z1pxRX5RhhCB&&wsaZVfwS^2ky!cQ!JXQTQ`KUGd@*(f0~h#|<`-%^$I
z+&@!jCML4V=Dmj<LR7?2VUxJCWMt(q+w6o~&K6VI{=qx1cdD-R?4E8nRHWn~37bis
zM4Z3xpTmaxq?!+X@1pUFyS+w8%RZ4~cGDMwtfX+ITVhj~epJ6yqx!>F;i5jG<gu$G
zG|90F`F_rh+cnycX6yTl699N8T;Q(wfiqCM;-qjgVH~EiW2w=~>cN@d#^mbD;v2x$
z@vQ|lASV8o$lXgiVxt4D!fI$<(xc{r>Fm1a@CS0+#i)<Vdjol-2EL4KX_OU36FFeB
zZ$u2<kD&6q&}eFmpAUsb$a=1h50U)zP5)Gn7Uzvuco|ES_iiG%d4;)AAI|MK`DoCq
zJ#eG+Ru0uKzJGb498a<N2KRQsWWq=b$4Sky$iC6G@yRq)&QG|%_yOR(M4=fUSz$$q
z9<Vz;>Jq2?(&erFYU`Tz>5}z;K`r#6nv1{N*Vq3qi3gZ(Y63bf9u@I7)5($0gY~Sh
z(4CiYa;Cm(z$8m7Nmu!uEf`$=wT71!A8znk2yG`0y1cILgIa;34@P<C^6dfC-&F$u
zHOx#C6gk3IlYG1#>vPu_(Zh<TzLRd`voQW*`&S<Zu;kzJQJz12UH?3|VXc3*`m_jJ
zheq#FAqcG5NFK4#adqFQQdt}sp!!Q3ACMud#&FQf<bI&W@BHqhkM2_G5T%kXx%~mx
z7LR4m2a{2IQO4nmjuHY_hmQ-mzCXl}#VU0U{nVQ}9@tPFZ5o)gw;gTY089Z%wJoK0
zoP*nhrO#1r>C?EdKz*pS79<eO^@)TQ!x!y`>@Pxpr7be@{-{YO-nxUfXxZ_3=YVQ?
zHGju2pN>St2rlgrGe?W_E<5F1#Dagt*nkf5c{Hl;U&8<L#sG2<{rbp5Lp>fl8)?xy
zG2Y_kB8Fa9rAj=4NNL9o=@o&tzbZz^Cu+Yog+%kKZ>Qr|sn4Ax5omakrDpe2n~e?N
zbHh{bydRsoXhCTn@7u9VSY_{<P%p6x^%<=F(7yNj-p|VE9*x>(sSM9xf{$|p+Pnil
z8Ctw5AG$5iwiwgYyw5x(V`aTQ!p4@wSD!!5mgFRpvRoWtW0LG@vrZj-u-f&V{O8o?
zulM+QEt?9xl(N{tXt5eB+bClQpEXK%>J%Sz@&2l<3eEQrh(EKKn=(3~!#*m{<#ySS
zuggXj`%C;!HwXX$&psV+)@V+?4n1Oll|AJY5*}xG6UjeG$-L1BvXRyEl2_Of*4`Ks
zmQ7G7e@20E8XM2(`%fT=>NmwllD_(G79ad<@vKiTC_BL{yOM&%-1w78+z9hznnaS3
z-t74{en^WL^%t6-!yyuzjm)B`ya}vgus%CZYx0_sUtU0sQdg?gkaT42ZSw8zh6jcz
z5lZtry6#)B_M_l*4Yt=@jBcK>LIdTrF)}+t8b*#~jn{|uZ5s4yU!wndt6x`q03ClE
zL_R^fDg{4@+Cof9{J@zy&4Hdu8XnA2`ZoaM%4k(nI!x9)XC|jGWK@_gwOKRYKl`Wr
zpPm=-2b!|smytS?z=GUL*7ga4c1B^dS-CjqN~+<915$A(t6s;Wakz(-zJ^JqX5FLT
zGeE#Y0K!k7(xcKT-B*Fn+ihq%^mL^*yQP%hi=_CYttB(cST%DQoB|RSzx_?V$#S`a
zyVv0xyq2PESxt0c#r!Tj^ac4RgaW7nr6@2)OOVM$@=yvnO!Oq0$ZQqo1Fs~O^7l*o
z5wGHR-^^0$^%W<-ny#}7fn&t}6&VAFaYTj?e^jlIzhq*4Ryw*uzIiWMubG{4EqP~l
znt2u-vaYF-8NF#HAufif4FLZ1+K5LaGNho$4z;dvFAwFaRt{d{a484BFUNVeiv}Hv
zzfVm`tjfx8&W1l1Vk@P|j17M$#ik~l5+2IgXJ=z0i-yca^`lHADpa-#7LAUt(<CG7
zv2D#HoYmz|ro0~sBjuKTb#2apV8$JsYE&u&)gCznuwmPh(?6z0h#|8d`P^dHmB_oy
z>CC?<uLGYFy;{b86Is(um|OmEo1DE)I$w9_3`O|8w+)T+QTU8WVh`oFIaMfwtlQ__
z9~Gne0+G!1FH%E>oSmRuT+j{4ep^GHetZk8*{Q{V8(`+_Y|DohW3dnI@2PtvfM&dC
zPsGlXQLC{NZbn=gyoDXbR^*tL5u#!UnhW+(pViPfwxKI5JNYW`*NVq~00tlv0s&$s
zl~|CLEyY5MI(03qX0>UZE|k>T8mXfBG_7Z~12QxA?_AY`)6B7nvJ@^*LPt@l5Xu6m
zzJR>JAZfs)DZAo^;L;1l?kQo|9bNl#UdTMv7$1K|nC5a4Pu~l@3N8f^Fbp-;B$^~~
zLjG>}JN5J<Ya6G}ar+^Xj{x9SC$(3w;X9t4GcZj0?DbL5H}$(7cIuO=gQAG(Ch@-g
zG4q6snWyQ9Ue@F7ECP5s)iro(10`M7b0a{5UJRiL!fep3YFJQGM_8rRa@Q8F_YG@4
ztrJ>RIab9DZcCf&)N{Ms0LF%2=Hdfl#+`G*Mq%KLFDiSJSt51}ZS(!cg#yxz-K&io
z%ljS|yBNI%zwt$RX<1+kQK1*4p=UDPesF!H)!g?!F3tY@0kp<E;N_3H(U8S{-2Ncs
zSTU9^0%MEHwQ+XO=kpq24q^IV6in<M2oqHW49uKG-{D^^A<3`shRAoX=#?ymcyGVG
z*oq9oba3?&l2Lg~C&nNSAW;F4ObK3?pTpD=wJjD_z2R#<P00Es(ZhU$IXV%YoNT(n
z8MWO#f^M*Gx`86gxLDJ-pXkMvQLAQ24Q>E=3vEv==O_t=SlKh#APb3&Qm%5Pj-F}o
zz;)^f0j>2m=*3xuUdT9zd4@q#78?--$N=c+=9bzgH223lkB{#Y+_Mp|32-Yqp^cF~
z7f9M|h!gUObPRW$oe3V)=88yLsAh;(J28w|-s=3`+#XTL2aWBk94+)IXLN&=HK!ux
z+$Mn~4k@dJwYp7gt`5oMGsyYBBTHJKyL~2x%(}8B-gG>wEN|IXH~QiZo?D^-cL}?T
zae@Yu4^d#ZFf!!FbmZT|AR=rKqXlp?fbe%%hB_Z~FBJoO*$2pCjEzE9%^-&*vPFEL
zTkpM6XfBiV_$@?_?eBn|x7*h+2V(0nG=sl3UzYjcldKfsR4~5Xr$S7X(D4Iaz#XgH
zpK-?)M@A%@urU{z4oU9vXSWp79j#~vJh1d%dTLd<^LcVK{$OXED&BLvJ5k8<8<caX
zY_{Kw60u}-15ovuwNoim-)W_PkmdU=buOx_RtT>$lb+N~BHvPB(GgCx-KLY)d8U6c
zR8yX_N=Yl+?-}7SQ`e}y+PuqG1nb>EQ$?7uq(hbE^KR(IW4b1DYr^GY{4(=zTTV~+
zJ&SfbA3&vF6z4gnV`sbyu?`!1E~>@m-5QR$Bq1^CY0w<ATKv{DQtf<h8=s4j*8x2@
zx;2D$NI(P9AG^Ei>DO<a<@Lq)F=E<{!1E``0H>%;iQnN$M}dh&9U$<i_8N*Q<I$RA
z-OrKbkLZ!=K8h+dN=TerBF9i@wNiwQjxyU#K_ocqx+>B;mPe|-&jIpXws27S%@O|l
zfY-PvSiS+0D1F`fW-A{Yi7m@oEq6ci_i4L;ZRKQYw_av%6Z9Vl;$W*t({>tcFPJ!a
z#AX*ibdN5N3?j+G4KVyFb4x4|`P2h>kag<wE6sNuFN=hE4O2EKfkAnOFn5Vml5{BL
z#&FyXz;>pK4J)B(nvZ|HNBf=;TzDSjf7(3gZjsLMiZ0C(p8(78XwY>t4br28LsrKw
zRM>+npRQpS*$W`;qqh&{R1oQbYeP`61M_mHi<VwGhFeeh&hOlL`lXt+PLKe`>(%3J
zr9TM@GlbaX@<q!f5IIL2dcv;BuKcugI_x#%6U}E#wi8(tu1|zYv5Cs>28jKQ?cX;F
zz(o;RVVAb+6LgTl3ih!a!eA=)HS%9f_X=O@Qh0zDj+QJg;E6bjQCFaAq<-sVjebFX
za9`_?jS~8+ApZI%UHg<TmU&mZWHHzZ^j5a9RR-sKQoFwCEO%<f_!Lzv;9U{L(Af#G
zYTN+LwxU@NS)RrQcqC$)?^S&Fk%lV0b&m`0>}}l$-jJVtDVjBx)t)M?RnHcqVc_u+
z^9E4sl8&%`7QMoGI_|1<UghaR>bN{A)qS=hdJ;<KTL0<;^kc1XLpq(>(-T4G!&?gj
z`q4a+D~3t%($`sEChGv^2;5NDvsB*jf!2?6#pLyQ>0NU+pT(QQ?245>V{*H#et9+}
zeKn-KXl)JgAhRT)`B1GXH<VWZ;zzShFuWz^3y`Q!4KHjzu`iz^A6>G738%X>5EnJ&
ze_FP%Od&H?wM?`S=^oK_0lk5Y_qo?U>&ZDNH(au;<=uW6GewX>at@(DXMNGz_S{+g
zShHv!Mq{AVy8s0rA3X~qd>RH`3M@9MK48yo(d+a~E_7fWSS~T5*ol!@X*)5namv)#
zWh3VYOcwTuIaSIkG5V7rr3EV;r>Se$Flp<-X%eVJd2O=8E5+1Z+Uvgi&hLba!L3D7
zF=31&R?bCP&hHw%b-z4LOtDRsEwZo61ba<kZ^a*jC#H?`yRG+7!hI2ouKz(>mq;!>
z##$#YnMb>3P{hUl%zk8_>7;DUPt?4y$Zj3~AV{s}6@RoAMK&#;<_?MXRZ;c;%(^ws
z1U#b$I%^RwYNwX;`w_GNzy-1s7DQ^t1e&FKf>f#-SkSxZe4rhh@LX7NX4-FvdD^bQ
ze1xm&RorK{;B^lky%pl{;vSL?E6*vOV}47voc&{#lJvp)MZPzA2W!E4G|0l<;VqY`
z^P+=gPlX&9I4Q;}y-Y+C5Rr&w+Up)KH<B>^@c#C-lCf|jJ&mp1>hIb7edHl8_5@_k
zR=<4PCb-D)T@^~nVhm{ZPyX1fCO6~-ccHyxl8CMSDC5wJ6gZD{0|dCYInF+1`sQ;X
zvN$>6y?F(R-tF!$ZDXPBlMgwl>uT%{?jxAk<SMVs(&M%&7}OdS?UtaMZ?uiSS1T-!
z`fg^iaQxXL$7O6-JC?*bCF(h>KCWG2iNHouw-&oPzR$cln`2U?>Ix}ojT976izVM>
zGRIAdx$Yr&aL2;IIX`Q7ny<sA!AYYUas!wpex9=HI8G<pT{+t{bc2nYY%+-U(_yQv
zt@Jyj6qYz|Gzraj8zUj?^*`wLC+B`7$b@~lhsW(Wi>2*OQo=tu7?mZ$><r%yWR}gd
zhfn(OEJqY#KVS(bg7!9a?^2uyc5_-FKc@R7A*W30>ubTK^kBHvVlJ;h`h_vfB1DD8
z<erkfi@gs6ZiP<$g6nu{X8x4I>kEQ8)0jA?@Zv?n4xy)wiO%Tj4e>H-vv%(FScw)a
z3jX-erihAVS3P)tb4XS~P<gGUU=&*ch;+|LK7K>w&QL{ZG7e{fu=|-%<Ho%F^RB~l
zO5VJbCWxY9muSV)xtI1yl`~Ni?>{%qDEmw2eNCYrGmkGgf4DeVwaK~Exc-oNRNnH*
z!dSRAwsg-X`>ceM`$bf@MCyE%EgA8|Sf>$1s!>#Brcd6>^?uTEvI9#?ZY=ua@M4qt
z)5ttohhArqF*WDW0<xUM>qXH8as%#}3Td=W1Ja(_5-qhDD5x3kD$!^j8fMy-bRX4=
z*_35!%C#Ks`g+*YHniRT+TCTMQ^PBfqVfL83C$^$ZRM<UC;7GCOD04>^B;7Cbi{!2
zsOY}NR&BjNU;NfVpJ%EDN?pcpHspI)f^U<G>y+@Aw<lgHq{hlz58Z2o9rPZGv_`~1
z>NIjZQfW(fo22<TG@Y#Yf6cc4F5u2Lq7hhs@N}<3mY!E?#~a;ikoM}wjnU$mbfa@d
zz2&=fL#%UqmrnI}XgC~`d8;(%hXe#}GXziCC_fahBGK772l=@+$c3)n<yy%!%zZ~R
zn&`=_f;z6<!T(viUDU;J+4@PcP1%w1vh^#T`<w#O)P(Wia<x8l{yNxny4wf!T#>+H
z5z%0Gr#^dLH;o>KojmN*BS)Te=Y%g~9bIKTlx7zgbKC<C?^(jRQ-(BHEQ>gbOFB3z
zoXH5b8&f;a)W7BwZt(R=p#*;0nS`{FMG1~AU0L;GbmY;GO{+ELj~>HzoXA}&(<>AR
z8;|>|!7Jd)CuznHyl8(z_&bGKS$IN2Ix~9pwNn4M{atG=@tugm;)yLkDBB`kb&8>Z
z(qF;d-x9uzE{YkRZEeLeTRYBXq*t4U*RKdfJvM6s730kGzc7gX*hu}8WKg4l5w?&g
z=N;8SqqRktgCnI~WCUwz*X{>Cx3FV3Hb_0fb*(fC>)CSKd~lW?fQEHMiBrC8ywyA(
zR;!tV`Y_c!-Z*}=$YdC`uGZj$nD53uG-cy_ecJntfr7|+CgrIHUAy6&_ejJ#s?O}m
zBQ-s4i}hoAwc(ZCv1&@t1?)huE9>rfip9peknWYOg599|@P|~ApTz!D^6xY)R!^Y2
z`D76P9YGOGNZd&2F)dwYte4!#vc*GJYLmC2+SD(9i-}RtLwj;@aJ+AT6Ib%3%O~>k
zON_Lh{T@rYL(<Tk*c(87)#a^z?7xmL{3VVoMoJ*^84r@>HVT=>Lw{?f{t73pZ>th^
zV9y2**698+tgZ`U4bJ0Zi7kRFnKIR^=AF=<bsU2Du?UOmMFh&%#X4zI$8-mBd{P#g
ziyhO8N{r@gls*Pm$Q|xyoA4!veKN}KF#3=NjfovpUs?&5ieBY$|8}M2JHTtkHUhh-
zrM1-7&<Tb(NWZiXo3(l+>(=NjH5QrPE3eXRtE4pZY?Jv&@5E>tbeX9cDB(M9uqjVX
z-UpZalzm`9!g}9A+a458zMhnpG_SERx}{txI~@m-#f;fhUx{258so+26Z0iS1-|~a
zI3z0Iy}=T$NN<z`0b*~tlv%-ai2w6YrI$oY*uxo?cVW@=C(NG31t?(sdIn!dnIH3s
zzln;j$8|C4K>IE@%2}(LCd?Zt?ci+6>pZfDN=)n*)2}-c9{4%gXwS+4egb@AuR&yB
zmB+~fUmE|4C45mL+hJV#i!D9ZvbW}Dww?mGbKK&<=7=jUX;{Ic<3)va#5&!wX9vis
z!(yM+($h<Fsq~;k32F+uJ9dy%uvj@&w{R7^>{lEBJ)1SDju+Uy0fZ!MhaamO>&}k!
z$GKhf46NA{zFPIU++>iuFgg>@3Ad3>GP=G2&f6B!l5j{Ws@JUy?PDhzQ+(WY8rDH+
zISlG`?IP}$DIE^%17RxT`W~F#v$LG)CNR0S;>dDJhWwM-EoydiYxOkVmBNFnZC5sK
zFUCQi1YI_kDUuFyZhym9E!^A}Dz?o>)-^MxZ+i0jI0&<SYEBM>Scu)L9;tTnE<;=N
zLv~@MbXLKZBqI0Mi{dvQaS-Y~^GOacP2uW|K-y?@%U`0zxY91dP@+$d{yvtKSD#_!
z5=C4;(ZDE_6fPle!p>A+^T34u;_6M>z)Ao(NhqFyX{(WV+9%~+(p$p679xMN0IDw`
zH^QCZl|b0ukgOi!ujB4`g63QDnT!uUUe2qmd=wpo2fhPOkTgx*u~N(UA@UcY0x16b
z=d*|Un=}nHX)fhgt(;DFnIxZ(elh%Yr`lg*=R30FV~%sy?V(hZ2kpXAJ8yts%r?5A
zJt3@G!)Wcw+)o4i`;uBmo8&peFj6u_^IY!UVoI~Q9N3&&zlWsY`0MR$(}<jUsx#B_
z5z{22^<@dLrwJ@_Y<$~+hgGxpLg?^8L!V`7818spwQ#({Gur6--G)A!hsLuFnM6^_
z%RE<tYBg}KSr&WVMT_bs16^~y8{qxmqWy%)uBTI_q>%@Mq@=KQQ{f?E*D^1#DZTQt
zBgn&Ny-Y-yh=z6C^F?JD_u5Kr$R-zD$h)p>G9u2YDcL)rSLwOtE<=<K3nV#j3U!=x
zflVwEInS4y1#Ie8GBF$UkrWQAYvFyTsyTtaDCNq&yJ`+<n<@c?oz*p0w%l5|0rn6h
zRkf8V`Qs{&>W67D*CR9Nx&qbOx*tEUsJJI$3>BWIY+HWWclBV3Qa9-iiw!xO{9yB9
zzjSSjLa8|Am1*JmRkG$@M60}Vm#q?#gHzG^TJuh`?T;>xjiMJ)%<OMpJpn?FX)Dy7
zx6aFII-)c#KHh9j2~|1chN?qH+>%XFj;qeUk$--7eP3^f=HBHSoKALS14r~v3{<zp
zaJu&B)S+Xa*Nf7!VquFLO-4uEaQimO1?6?}nMDcP+_bc%TA#StC(i}WqXf6;W-A@r
zbGyp!SgGRwVFkEIDz+jni@o)$X3{%`n!6i`%Np*rFKz$5OM!L)OgOIi_gP41juoDM
zpMwW`6om>tec<uTR*NiRDH#MR<IEe(v#&7nPKEY;)mQMwr|2$X9}f#IdrH8sa3%CM
zuyEgv1WQ^}?bGbQw%h8_AuP9nI@g$4$;Nw3y62+Fdp_w}p$F{ND&+sHj$G7%6^4gS
zL)3~J`rZ?Bza;ad(}{&FSdL2zlzdR`l6tCS)3$PO;W%MMR3~|Sk*CBkstr9}*oGZe
zr(f}Qw4Dz#v)a_<mJ*a!v&LF@LWcB?LI{_+rw+UIK$H#e^e6q!6fSa2mU@(a%+a?H
z`-YEiqtdZ}4Qms2`c%eWirP337jY&OHzd;ua0^Q}r~0{8R4XWvb8_S1BYXz$<Un$e
zOha|39+|BR9{#k$kk72Xsm#Xoeo`}L!c{z-rZn3ieB1DcZM<D6Rn<A66Uni#_}ZT=
zf7d>*Op5yk*vGhbnxFlea5wy_il<t%soh@a%~>UMnrPVBMLm%l;x!&BeP~&Aib))1
zl{MMa_40nvfvXxHNpeIsFO$MtCE;!U0p57gJKU1OWSZ#Bcjxt1nV-%}6+YF2JKq54
zlQ^rOkG2u2y$#T3QC_8~8R7QuwLLaA-fb7El7aGk$M6@kk39)LFM>-e%8V$|f<4g@
z%K$;rWRM4>Pu1>kwx`_<PWj*p<uo7w<i!4EE@Ee^5zk*GcgP+mTo0Vd92CuH=X3tK
z^N4peyx>?wPhGZNjF~XXYA{l=ma(#Ft-DBLPVl(FA<?;!{fmMKIvGpr6}4smO3bms
zDar0E)374TGQ(>qKHvQj3%4Ree)T}XvtsZ<OWH`ZO?}nreYWMEMmM4L<T~qI^Yvmp
z9M&G;ApUrnpb%@eI=Q|56^pF*<=Kx;<HV75o02<N<+hmBcF8UK*yg!iFR#i@>Pukx
z?UiJMcmj`43N}hvXO~S7yB$}#qO4v54sLe_j?O2Pt3gJ&19C;hNg{nSUSwXwQ~UMq
z`kT`I<jO;!+_D}ng~_mGhlLXwyLCyc$Fs$Ev!&!kZu$EDfF~6xcOC`YtBaU~x-|8F
zS8Uw!E*~&}A84m04E``6|IKW9`?mcSUPw;eo~}(b+z#5IZF7H?SD*Q)n*2!T)Wg0%
zYP8PKDUjfC@<``c6l6qWvg1~>&8rB@x=PJry_b4mDni^8o@oHD>=AzON8ooX@S}c&
z!w<59$8&y!U!`dv-vG2Xz>Wkjgb>bn_dDSGgX0GgjNqu;$>R`+{sQTMM1zlWmUg7~
zUzo5@Hq4YN?0FEsm4qe490g?WNBAVSn>73MJaetXWbQ!0XBw<}G%+J-<QaM`h25mf
ztrE)IWGcVP*JAU~YM6ZC-c=BK-B+&whRIF*>WoV${$Y`n_&ytbuMW8`aj>hi!ITs8
z`rU^;XqtqHj@u-`2TZRL*AL215dGM+eRWe;Piu3^=<>wafK5gpaUL_c{{}eb-V|bZ
z*x0I6@p)M(&)SAX2nYKH(4wX_c}Up8)Ouv^LjYlo!O%?V7(KVg(s-AY)o^UX?It{)
z{-h<hrGFjL4O#08FBg_)_H-DF8kFm}=o4huBtk~48T=$<aVI1s0W1jnbRQ)1VvDqT
zd&jUc(1D<Av};0A>G|%;OHBdZ6kc+UW9@b$&}a91`yL`TF9kZJpAV<Vf41P3S@<{!
z7p)%{lywYGn*O%rqN>x9tyqZuN1*k0O}_Emi;C<v>*I<eGe>#hj;D7pTUHiGjL^`;
z{^B4I5YwcJ5;#&KJd{a(s-jb#W41%2-c7^0LO8Nk$UO+T9%hWsi^824=ty+7Al%T;
zcxClUZP-t^-DT-C%|}U43)(?U*nM5%yqY{*F{!huEyr}O=#w)_HTe7ykSRHX+{-_C
zC)R|jLCEsCYn)?HBz$W-M7mn8XK46zxpOX1L}!B1UGIzK{@GT!bA4%L!96p?{$5Zy
z#fRmAT32^(qiP=UFHX`LTM0KnUH>{^YHThC$r<+{Zp%vdWt!WPyt*1be&8#TGf0%D
z@STDM=Pr|V9eZm|vmNJL_bh?-l<I`B-8v5?3zqYs<e_ldERu3$#G33sM1`!mY#7z&
z+?|GFnnqN#_+f1aWaN05S?Z?a{;m`>>Z5VrrBvGI(*`MNIF#jiY+3s*k^6p}S%|Pd
zriIu)#r%~(M#2%~4-a7zpCO5H-G;>7@iqxy!HFp2qHCKfS9FHkBdh@=iuu+c?y;Eo
z-?A-`mws^L@cRktw6T}Ph9XgIES^p|+!I`iuixNx*<T11p659;oJFRY>d~zo?AtXT
zLeFdG4o{Rsu5z_DWeSf>oMJO0WYqi(2(2Hh%HgB3`D#QkS^K(;-6z1InAVD3$HDL6
z(dkdQDlPH*uy3xG{$5xR?lE^eZ9J%N)r}Z_;@~_KOUB7oKo%zKB_T{>ylj>*T2sY8
z%fUY|orhz2d~|dGs!!arTRkhQrbl1yQGY7Ql!<<ixiD3^8PsR2QPOxD&aYYaSx}3H
zR{AN3a;N5`!MgsgPX1Ytj=5|_?hCo@x#VZFxrZM8>-WcmB;McpjT;gb;EQAWY{T;0
zpj$JCGYanp0O?#Cg<+4@ug_3J3oN>sD>W`;t9u~Fi?(J(RZ?+|h(-Iq2^ZD(XX-^k
zvlt&QX@&cEBIl^qfxTy%SfKZNyYD?BzL7|12o{k<-_Nn)0io~L)yf~xMjVSClDi+j
zlc*MP;Mhu1kskd7D~&3ywDUxqdE(&g*j=(5S!}C@seTrw*Mdck!eb}I4^`=$?lBeL
zV=4fO(2?NyERFSkeu4tG7IeXJXpVt|LiS569XM=GkY!PHX!|N}S*p$Y@Mi0`hlZrd
zG%6+^j<`w}O4+ivDuul~VENr!x|aj&XKE8Ji`qfextUw+@24(``-DW#9M+H3o_Igc
zchj}Ha9nB;+PpN2#dZV7jegg3=sZoJs;FGD96tRx)ls_KljCHmz3%E1{!nI7DOIX}
zEG6B1$8Me2?aHl5r(9FhzDL(YgkK+mXpz<Sm5XOYq573}W`%!2_7gV%K>3dDF{$!m
zVrb%i3B;kE<;<$>I1IZY#Y-cg2hukjxD9b=;dD!e6Im2B-owoPTMGCEyx4s=a!(S0
zVQ^V{59(kOqoGgHC^Z4;S&;4;NI<+N+fs*BK>9ND`u*L;N5d-H*o?prt4E`U6b#30
z4SvQHl%@61A`{u~$=RQZ6;<rZaopk~-JYnQ@ZisJTXcJ{GGG}Ift6S?)q3dFTiN?m
z<E~E65>wMC8AfTPT#nn%1}VOW@fE`tpIRm3emSordQhsdf2+kgoU31$#&U~apt)}D
zi$@wU<v<l{wUt~lML<rPaIN>p%H>+cHe$zsFiD}NswtkKTI?7pkuMGGc?Dz|mq|9O
zH$V^F^+y{f=jKoQmtF9|F8|W0Pc1fKm_Hgrdyj>`mCjgK!JSj%G$lT!YeIOY;|7TB
z$XS42_V6ltryPd5gVL|+pQO7`wNuQzx(JG$tXY^rH~t0SUw0YB#o|3JH5Pf$o76cv
z!$uYRzI*ZBO2F6rUjytvXAN-izjPW}EK@~S)@X5YxWcwDdi*yj?rLSMPJH1X%Q%e7
zx;$+WuH`p=cL<I$fRV@MDBaHq>vcJM6R}EE^({aQ3F-Nxcgs?h^@S&LvvUcWu~+g1
zX4^v3+AQUQF69i(N3Vo@Xv!z|UEQsj^-zT-;xoGpB8$q@Kd8y8V)iKqtmKPt%BX=e
zz?zJVs;K@*#sykmD=z$D(RJTqqw;bTuX%-ISxiPzp9S(%Hsax)V@N&LRh>$$oR5}f
z?HuE8g;$B2lP+<^P6%aNyMWWI%|$sQ=*!Q`zovto=^ZU7ifNb*ZFY2to?R&ByEf^K
z&5GW~IK-@A;a_6@xDHg5AP;9_vOve}kE-NYbgb?t@9X&;u~e4Pd|NrW>>}M&g?n0`
z;fR*9cwV#$lhMa?3DYPgOzB#bo_MWLq_sBm43h@w$r9XO-21Z$ki|G)@!9QK#n!z1
zl$uiA{o-nflWHw<CNIJ)?Mk-N=sN?F8JQ1=e+{g^>>luaZ$&8e*{0Y~UEhwF{e*eR
z{E1-~RGvcyZr>!Lc1})i1L=a6?c~qI*x&zzgsx<+p}^Bf79ej=w?1{Cd}3%i#&_tM
zHlWltzddANpZ9cM$fI{sw+}=Zs6wu63=@y;G<;3MVoN;v;V1S5$Q8;Zpr>>QOMeZN
z#nWHiVvsdi*mTl>?0wjB^_&pU*rceC;7;nVsH=qS8hWl@%O9L8P#7POx<WM7BK=Ie
zpN#je*afxS0HaA4?$9Czziq8iT_caU%IKI?4u+3=4b7zz5$z}``pyCIe3)|IS)i|b
zSZy^VQs~+7n8-L2mK=1-vd$m49VI+1z=v~iSz3lF)LaNfO-Q;J-2hOxt<#xiCEjY{
zJ~u0H3U_V(l&Pr@sOPk4e_g4@&80;CE;Qi};E~0sWhtN8x;(6|n8tG7*(ei0?n}w}
z`qt?e(7$<o<Ko-MWFZR1#ADGsU*>vOGVJS@Ul-ZmGGZxsYrJUIOl=^rbv$0WGqp)l
zchsIvnbuP{{F({Yarf0k*q#u@_=LyNYA9ULyJ<LdAWz#wa^bBpYzDa~?vVuDJ3>8+
zHwcWuE0M9S$P4({g&2jHwCI+E8)JFzQfurI%c|pRQDw=^Mvf?-wkN8Q^>;56Ob$nu
zjs+FvYH^m`JEXDEYh7$T*eyE}a(^_a8q4yGBX47(J3Y8V2^)t=YkfnhohU2Xr$6^J
z?N0o0bEx}E{uQPD@heRTZfuS%(e(Ga$r?;WJB|R11t`<&kyu(ISiNcH5!c@KX}rk$
zZ-$mvyhK$U-Z7a2@KnB;dXl3);aLhvO$upm{O{eP7PaIvDQWb@<Eb%dG-6c0K?BH8
z>raq!=7`-zohMA16zlvZ{>=T!h>Wbg8HTewH0C`4y#b2&bq<v>pyYn4ABfTwV*^jJ
z>{3H<s^BLpx@uQr6$e6T32-4+_etVOx408Fm4zcY7K*pVtvPtiohgLI?BXPMZNbrP
z({}^&!A^zZ#LAd&<p>`JfHMdQP<SaZps|~mIEF2`<;UeC5~HQLV0_j-upUahhY@|c
zCf3pRYBYGWKhJM=icS9glJFHs<Kb)R?bU{(20r5hmhF$FlDt!k{#>4Kt{p^Ag9hAu
zbR#H3>FnY!oe<lov7bSTKah;Y_>S<(-KwB>-Q9%Jt4h$3(jF<*I0jeO@{yPY%jGe%
zMQ=M6&bO1gBtDzBIYc9)Zh&p38{oyRC)~|xJYp`KKkxD|=}_16Jn~Pls3BkR&+qu|
z+b@*L?@lp~ca61_iTy<Ij|(bl?G13>V7sDnpq37C@I|2*o7b~bg4Peb;WT6Inqlao
zL2IcfydAmQU2m!zcpLKWQI>UYaM(N1Zr2CfW#_Df-8qV^-3j%CB+Paw?C-#8D&%ry
z-G;A=0v{1iX6RW2KqfP^pQ5SxfhBw0HSF?BR3-OS@-Vh)b#<rlXrD=aI1+MOB=6oY
zRDHQ*y!BmGiP(|djTbSBmEMPsQQpb==Bl#O*GyezKrLg*F5I{{y-!0Oc(|R?bUUN~
z3;E*O!SGVrC;x00v^li6A6UXEk#}BIf^fL6d#r86Cu=YW#WyX!GeQW^l%cg8Wm`Py
z$b~dowDzz;c>;v{T~wl|WuB?s;x{S%ME`Iq2RarIuoALUKQuhCILW>MpBEU%N>?vO
zE=xuJ4I1j=dK1o9O-%!6N~%@odh_ZTk<~IqDiTWJe}T8s%SYB`y|;+v*?3nv!_f(1
zg$#jkTpCjJ3)~6Er)-Q(>xA`X_Z*se3*BaQ4#+Motm-&28T{rar`R%z?V%RpYFBiD
zl8V%7Msg5BV_56m{P7HMbcYq85w}>=C`Rc+Kc_<6ns<b1v)LBLsp5nVweg>ERK6@1
zH8LN^WKt|iadsA}jY)KN38rqF*3SyrJiJail|YF})J$n&W4AvswN6XE$Gl{~Eqv#z
zZD=5-T;3^BErhRWH)Y_Ovw6f55gr_`@1M3oNInc-X+dtqO@A+&tf3Y!`L0}u|3MXl
zQ2vW5)IUeOfMA_cy?R|bGGI?}W)Lxxw#$k)543K`)b8O9ipS!BUFkzE-{)2KR5e&n
z`>=6-8b5yRh59RA007J*rl#Y<<Aj+xuCQQ!k;B(VUO@pF(>fTjq{%#JT6iYi!c;ZC
z8{zL16`esZ7VKV>Ft1gp0~k3jsKaeb>tiA);l#%zNj>XAbB=qi4b7;+Z~(+=KX>Ya
z>?T~>ct(b|bQXPl$@gkUq9?u-98V=T>8C~fGSEm4tfnd_u3`1VC!pzB_{ES0K#~w{
zHUOfGG5HQ!=2~FwxdK-^IN6k#kO~ut4-n<nZ`jzM6)9jcQnds_zB%k#`HxW$Oqbf%
zdgTqcR5fB-K&#W#sC`Hao#JcK?lg9@zf-;eZqbxktUz=Q6K{a__$%pwGf~|<%1{Vj
zA9nM`WDT8oKGCRHj?Tw>pg`sisvmPyspazTF-23W-jzSf?36ssv0l3YHbMtGO5}sQ
z^=cf1N?5hQ@sfyg_k6~<PWYUIg97G4ht$b-%nVPl+Fs-Sg%&bUA)s`-VshDmLJ!3I
z`i;x8D|2~4hoB+G@1!4;|KA~uiVowh=S2sWP{jfGV4rizTKd~S&qntbl5>fe((>UO
z;7Cm)YcqQfabB*yuR7v=&3;35<$Q~&J%v>xpQb&2Yz}hjxj#py9auxbd5JC_KR`o4
zIS>(+Z7V~m3kh{C{OpJe9t)Ejk?*WJxbyZ2D-p*jmN}JAN=%ftKO=OezfB}=tqxZr
zrtnGhM4U_O5hAJTd8OeBx1mYh5*8&Yy2{z47&Rm@mQ2I2+o;s8J8VMu*`XUCe@`gA
zR3)OFspbcu0m=v$`v^jWz%<}_$RjZGBQTS{H7eu7NJ;~o;G%}D{)fyJ*kLoYN_Ub@
z;R%KZd~GT1eQp+Vr@5vkaM4&LhuGtJ`0AOaz(l+_(O*y^VUBKg*{f#+H)fX$!z2fa
z9A598=ZUQcntMtTI-fy2vp3;!mf1Y5*aiQO%>sz89!e}(_=)mbH8ZXwJa~hzw{lb)
zESIL<uYTYfErJcIzm|T=taNymv;)EI;)c)hIdBMIR*sKEm8B`g<0!S2+qqLnce(G2
z#Aye_X{aIxD9Jutl2bL2%my*nAci&A=O5!)6scci8%8O&^hjxIhr*Jjr|Nb~N^i|<
zUvvc{Ch3pRpd(G<L7v7PR|oMZ^G^0fz2r2Vm=PgLP+nD&a=T(sy8496=`nln4zw|^
zb^$U>sbQLy99rD7!uDx-YGK6QBVyJq{v`Yccz)O<Jzm_i_(0q41|SYVpbbV2P%evA
zW(3nJ7ou9DB4Gd+gC9VBCQBA{P)law_btmGtD7-AOXm@7ULxOpQ0wkcJ|5!zVNtV|
z`q59sWKh215jywdtO-{Q=owZc0>FLQ8(@TaSgzi}^>*yb{{k!UNOdmr4R;$~#|Q1*
z^UqIH4VB<2R>#T5{(Q3~=2;x*^0e)sD&zF%m>HoPfIcnN)5EAPd3bQsEiZVemd!L}
zi<uvzo`ng?T=sTJo0O`YOpoDPa6D;bpvpZ^Xkb3cUFE_H)n=y6)STS~3lPa<^MH@v
zmTQChxyA<d`j{7=g`^izkxW#3iQbcz&L*(CRL>^}D7Ifu$@Oe@Y{EL5?ENws-Rw5c
zfn=*lNLy(x*+A8k(yJG0ONTmp{LZJ9BDHk0aaIgv<~}2yyHUrR_NVP&z8fH<V-(|q
zF;j+e;Vp~|sin8dj7THsQWs)1VaOX?g~UlinK{7}qn62aY$23KLDnvpJ?R!!{Pg*)
zf_PqAmfo^6YY`6Z>mT<#!`;|$C)<A_7m1zKqDb165XYRW$SeIUd?k>P<a|MA9rE?#
zm(Kg&zKylF=k^)6qno`e3HXmg=zk%P_}pBjwd>p3>{w?<?ttNyiQi#5KA#g$QtFwI
zB_%!ojFF+>tb)V(vmnxb`SIbzxRtf19D>UUeMOwRykiI>d%rn4Ke{fACqnUtXwgc%
zC9;BL-&~nm+Lt)f4&4~m1~zW}4rSs+iXjb?l%NaQ-Xq~C&ZFpOdXuNtxw6%I1F)~V
z&I+}{j_Qpp?2m*Cr6id93t9ac$^3<iimpgV-DeqMSB}h<AqnqX;qVFET72hlLzPLF
z{Y}J<m|)eTVZ`EwXBJb7Pho#yfxT-=NrF9dA&7O#0`dLWPoK=bz3GYwj+p8b=V#;!
z&|V<W&wdL=<^@n6;)107oJeoAnn57XbDp-E5kJq#!5woN1NE@?e;nIou|8Smb#?C2
zM|_$2o^|%kZ1$Frpp+b1M1J+BSTPj9z%EKEEcAWR>mrV4oa5QgIa3et8z4GRaa*s-
zF`+=a;%Kl%?R#OY(;)Z3Z}R~kD`Bu=L(-J|)+5AjW}V;A@AE>a?qWz(e>Di=iVTGL
zc2sJD>_kY^Ck&(bjl!-ClN1ySENWJKg5r)UJB&XvJ0*c;Yu}lslX=faG~bU`bZ+Ce
zZt*4>K&dv(n+=<D-8(<%C?3cyR6X*zySEEs(!jLvRj`Di8%ySZO(ef_Bz)({(#?VD
z#4}b2Pb)IQ`RSs_qpl8z=NBy*6vGPnCfl<#lOIwv^0#tmLNI$lxM*@gg%7Qp(CpXw
z5-fT0wsSoiDJ&?3mmMc;R>9eJNy7DuqU5t~)q1xng2ME!IGxj#+=Ou4VUaD2%#6B?
z*e(kEYB>QfyCzO_i(Sr?FuNmcR65d?NK{*QKB&@8W60uWNPUvy!hAb)YXs2{A2hV3
z0uZgDrX%I2rAbGZv<*Z3T3cVGK0SK_%nG`~yKHxN$T5~(RAF4K`|qT=&J{U7p6v`q
ze{{S7w6izvie@uV<bo89%kAx-w@*|ymy(gU`)J0sWrj!ieK($x>sa2ZD)P2((`$Tb
zSmEGwC7QJ_U_sv@S8izU+If9AEuZ67g(|k55PkQLFWvq)BKxzQax_B*-Tk1(M_~Ek
z;_gx>OzSHvm|Jx9jQ#x!yDN!e0Yh-t`c%ygK;&F>{;gqPdBIIs$b9VFCFtD}yxP$J
zAi+7LwV3H%Qct$RqrK;6?A{C>G8`mUdNzJ|8fEkb6tPT)+AhrObx$t>-?^4Ek8ff%
z6XzvkWXE|wzg{gMS-0I6Wlj~?)VF+IQ07VzYmRsKqA;el3?KE;v}D6p<@?u!lDdcW
z`T7TSMuG=Wou?PGcLpY%st7Ybs0Zxs@91Zqal4<dR?e&37my!OLKzKolVyC-tdGw>
zTU!Lv3N+e_<yYNrsJn2d;7*ELO}2S9l%wiTV+*L1`PmgyA=<`{RHkkWaec0#^P{~!
zfZl!uN#ZBySa=|o0G3^ddKZUQa=f@!Ci@aHb($g)&T+^VTMj^Fo49*qSY@D{rIco)
zs7x|_x#8jA;?KgII80p+lC_&26vuP1om#nG-N}Qco}U)>`81tgxCAs~1wNwjYlv$9
zHkpP_#*dP@LG`;6{nLN`Nr++jTG8QQXt&pA=B^4l1Z%Q9J}6o5=55x(bUB%rcKb5R
zCD36W^u{n~G;LWu&+{2vw8^$Q7&~f79(`IUR%j{=@liOxPy6}}Aa^8yq_sM2e@Vq~
zO>iAwt|a}nxU8`xQDqZ*WN(4oW=Wy31}cqg-`?JyZiw}~n`!wXQCCvn+D`HV$s<*b
zN64}8lwH0Ai`tOXobW!OcE`((;FTlmMLh+gn!|@qlZKO<5Qj>d=R;mR-R#WDFz8~p
z7fzUVP^z2JhXM%$F)Tf;=Lbn38m;<yU7K#i97EGpYbw#&wNY4@ssGEp!cOGpK+V|B
ztr2s?V1gNDj=ZUPtJNH%dxMLqX3W2Y1~JOuC#a1Tc>8FVtkk@dPh21%4cjKcN}JWY
z;7Nb7=;`*rt7i><N~VIht_(y{Q~d+te@!3*RzLnn1e?;?cbUWDhD%OL3j=K)?#tCV
zl=R4K$3YzUrwY?~C+DET6n2p{;r!xTy$(W|y|0ekx~=vL%KFB%Vw@${ys&8Q8$TbB
z5eHx<L<3}t_SWOM9TcPAG^^l?iB=x4xa^XZ`kF>j*Ew*<n<a--ch6Vr{()xZYGKm~
z7B0k^p8^ohf^_KJ&lf~K-~vGr_V>doZ<+aOOEO$?KMkHxL(lb*k|4{0ToY7dSd}}K
zcYfa?m7R+m;e_Fh8#yrT%t>dTv*JY_KJda`|JMP5|N82`{-i>CPNO_Bfo)Erkyh%i
z(t0Sco7>Or%Hp=%%iC(i#=Rt7_RVpLd?(siF?c5Q_>##I$K0x*c5CrrhQEIX8qJ0X
zw~o&1D{34Ye9t1rt7nK<h9<nyem&f-JHKS6-pX~nM3__yf|tkQSixHP0gQN2%^^Z<
z%OCN=!jD${`IcW<X~c?2pFQW;=j6&6;cR(bcw*mM?5w7G&UC%Lahh@*Qk*JECP(gM
zX7Q=N|GxUSMWv5$5Xs%5A;XOqa=+f?|GJ~%%HtpBss_sHZYQ;_@H;n&AC=S=ojkBG
zr*o)lbc;yc_KMHxui;)LiBKG>i-6<x*Bfbi@osTDm8#L|5h@ys1a*{vmmSk>WU=~X
ze|$g_Pk+t8=-(nc;%?l1qM1M2<OoZ%iE0^!u!cP)Tb$YRNjx@<a#xW5TD+jIrTOBn
zwp3iAe<_U&*sl18X`3Ou%r~ZDT(g?DEc%+%c==Zx|6eUv9+U(c#Wi(n-45C|Y&12@
zay{}c^UM)T@t`afB_*#?gfel}G>>doS&t+$wNxYz#3L~eqylk0Q`8a>)J)AAQ&K!K
zEp2I<rkZJXmYv!6&v(q5_kQ!f`R04y_ultFqzet|D3$2p)K1)-96f3m^72f#+;*95
zz=H=+XTl2BBM2^6BOYyl;<&x{<12C<?|q#M@{bk}w<&f7+i_jZ5H{#gSL5ytiOz*J
z?@(zJ6wQ#nlD;;)GqFt-NC2~%EvV>b*>G6q$p$tI=U#<_wEkA3bhs$KYfT}TNvA=X
zRV5#95`cUuwH`!*GZF|L`>P$9xk8OV_O<hu-8}fCO*D3Oqr)R?)p2HJ%Y<*8;+-(O
ziEG^BWv<@Y=?UFus#w1oa=vv_spTF`rL8iutm~utu}*pDtkl&L<zV+k%?|H^a}PsF
z@)*hx$3&L=6dxVK!_1Gmma+Ja5+JBE)yGseFyZKPwmM^TbcvU__&y<`e?wbN>6AgA
zv&^i>o!)yVjs`O<ddTg#ab3+;cqaQ%YBeJ19VveN?D^>hvc&+R&=48hl-lLIA94w<
zS*}-DJ<cN>ka_R8{9g0QBCY>%UQUyCiN)!gLe0V=9_GJZ-Pu-IIHit>hpQ+=Cdu2%
zmFD}ay~DF(=`I=8Gun$j-GR%qlb9&8)yxP3>xBc!kKqkrRVV6zdwm-bCNcVhgs5XY
zMFBIK=QwEK%T`9NZhnu6?rKZ4=TCLk)eBSDM}l%@dD_9b?i_MT)M`Ef3z#w`=Cryh
zX10*V^?TC|JIJ}cI*_#E-}RKgZy{l=2U+N2W`Tols^V}~3IBDDZ(0O;#69SPShawE
zF(dcxkH;NVl{Ix<(Nq!>yAK01-0Dxm^<T!fRk5<WHx8I#TMEI<>5Jh-aT!vUpCVl5
zfL+DrzkAiCNJi}{?xPazu?6`)KajjE(Faf8Rs!5I|2~xO%u1?mYAzl?7_=_;mj&o%
z)1V*s?GMglmCl8gbM8?P+}e>fQp_;9ojqme!LMj=F9cX|7^Zl2+`?><-{cA?+Mh8^
zZJy$1wbqf~0hWC$r8_j8Ze9DhX#b6*)QG-aYzi6TD(8RV^%CA^V9?~5R?Xpga`o|(
zo}*`9)b3d#!i7E@kVElLM)c6f^8J!9&P6kt0Zdon$#*qJ#Q;A(SOene62EfHL<MvD
zp7+25W`&uR@dXN<d3o*%5k?Ggt69em;TP*lb3TYoBNy@IYgOzCw>YKh@mDov8d~1d
zX3KX_)GWqE9hPf6KUIU734qezz<Rm;{%CGtE4FJPNtoR~Te-bNR5)Mwuc<mIogkJh
zNb^ft=C&`9ZcK&@+efJNaA>46ZB<<zu@q0hA@xwLE$PGgfwYkH7emRfo30`hP2V&=
z=d%DyqdK@?hkak<iPn=8m%Q+EQyr25ib!5kvD6Eb*OfQq+=G^9TGg&Q!HQo7GpO7>
zubTCY8rXOFhkmM;f;~@5(R-E>c53cPPJ4!}(Ru0nq^*}Lj-b(~lX)X<*eoO$+28Ty
zeNZ$!Vq!S!U&_G*TQ7KvSMO~|KeYo#YJQS98G@RCB}{4+EE>QCo~(=n;zbwdQoAva
z?za<8!5LK2AIBv6<{!=MK-Kh^hPQwf3jSPEejuvu&-~)ju*)9f8X7vY!=~XNY}?Fq
zFCIRVCwMU*{<J;V8|2B_9ZNaS0z!+fX9}Z{6q5;~z)vA~IwvMA4~^z=304h+1o}HD
zb9K=2+Gn|<wwolS6~_J5%I}SE1GNQc`vF5Y26E)hOd0*vlc1e;=iIq?fI~9xW^E)1
z@l*-t!%1u7Y$$s2-)4I;`i<OYLA*wNCd9^ERK1`1#U)0xjw!9|cPM^I!cW@Kg0NWv
z6Jr!2)~oNfs_++D4?#x#41XxGeGtqNJVeF5UV-=cqjNS>ZM-!~z~tP0p9P8BibI?1
z5|nS0+h=EGhYQvZ0b4X4zCqJ#ciV-|kIAdECK)Q=L5za$CB?gbWpO&)#%T;S7*5OA
z)-+R~tbvMDp*7synvO?+-HM97y~BwJMM}-=W|hXajQrFf11NkN*aUXC8CC=%-~jfN
j$ZZZTSVM@Cxrj2qVFyTxE8B_HD_{F&_WvD3f9U@kuA!?7

literal 0
HcmV?d00001

diff --git a/index.pug b/index.pug
index d1c3c3ed764..75ffbb0dfb7 100644
--- a/index.pug
+++ b/index.pug
@@ -226,8 +226,8 @@ html(lang='en')
               <a rel="sponsored" href="https://ghostinspector.com/">
                 <img class="sponsor" src="https://images.opencollective.com/ghostinspector/51b7be8/logo.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://wongagames.co.uk/">
-                <img class="sponsor" src="https://images.opencollective.com/wongagames/d3eb92f/logo/256.png" style="height: 100px">
+              <a rel="sponsored" href="https://fortunegames.com/">
+                <img class="sponsor" src="/docs/images/fortunegames.jpg" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://medium.com/@niksundin/best-web-design-companies-1872e445775f">
                 <img class="sponsor" src="https://images.opencollective.com/top-web-design-agencies/d92d747/logo.png" style="height: 100px">

From 4d704ca4ade8a698f1d646aad66469263bd57a65 Mon Sep 17 00:00:00 2001
From: Dan Dascalescu <ddascalescu+github@gmail.com>
Date: Mon, 1 Feb 2021 20:44:47 -1000
Subject: [PATCH 1664/2348] Mention other debug options than console

---
 docs/faq.pug | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/faq.pug b/docs/faq.pug
index 54a6636b21d..29ef6affbd2 100644
--- a/docs/faq.pug
+++ b/docs/faq.pug
@@ -293,9 +293,10 @@ block content
 
     <a href="#enable_debugging">**Q**</a>. How can I enable debugging?
 
-    **A**. Set the `debug` option to `true`:
+    **A**. Set the `debug` option:
 
     ```javascript
+    // all executed methods log output to console
     mongoose.set('debug', true)
     
     // disable colors in debug mode
@@ -305,8 +306,7 @@ block content
     mongoose.set('debug', { shell: true })
     ```
 
-    All executed collection methods will log output of their arguments to your
-    console.
+    For more debugging options (streams, callbacks), see the ['debug' option under `.set()`](./api.html#mongoose_Mongoose-set).
 
 
     <hr id="callback_never_executes" />

From e1e6c0c5b6309f69900e9ea9a898a914d61415bf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaras=C5=82a=C5=AD=20Viktor=C4=8Dyk?= <ugzuzg@gmail.com>
Date: Tue, 2 Feb 2021 11:01:22 -0100
Subject: [PATCH 1665/2348] fix(index.d.ts): allow required function in array
 definition

---
 index.d.ts                |  2 +-
 test/typescript/schema.ts | 11 ++++++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 8706df16808..83da784a8ab 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1381,7 +1381,7 @@ declare module 'mongoose' {
      * path cannot be set to a nullish value. If a function, Mongoose calls the
      * function and only checks for nullish values if the function returns a truthy value.
      */
-    required?: boolean | (() => boolean) | [boolean, string];
+    required?: boolean | (() => boolean) | [boolean, string] | [() => boolean, string];
 
     /**
      * The default value for this path. If a function, Mongoose executes the function
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index c6f61667b95..4aed0505b31 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -23,6 +23,15 @@ const movieSchema: Schema = new Schema({
     type: String,
     enum: Genre,
     required: true
+  },
+  actionIntensity: {
+    type: Number,
+    required: [
+      function(this: { genre: Genre }) {
+        return this.genre === Genre.Action;
+      },
+      'Action intensity required for action genre'
+    ]
   }
 });
 
@@ -68,4 +77,4 @@ async function gh9857() {
   };
 
   const schema = new Schema<UserDocument, UserModel, User>(schemaDefinition);
-}
\ No newline at end of file
+}

From 053fcaba8be914c4aaddaa090f10e0146ff347c4 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 13:02:11 -0500
Subject: [PATCH 1666/2348] changes not being reflected

These changes worked in my local environment but for some reason when I run it, the code ignores everything
---
 lib/document.js       | 12 ++++++---
 test/document.test.js | 59 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 7bf725fdeef..2f886cbdf52 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -140,7 +140,7 @@ function Document(obj, fields, skipId, options) {
       });
     }
   }
-
+console.log('Hello????????');
   if (obj) {
     // Skip set hooks
     if (this.$__original_set) {
@@ -899,6 +899,7 @@ Document.prototype.overwrite = function overwrite(obj) {
  */
 
 Document.prototype.$set = function $set(path, val, type, options) {
+
   if (utils.isPOJO(type)) {
     options = type;
     type = undefined;
@@ -925,7 +926,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
   }
 
   if (path == null) {
-    const _ = path;
+    let _ = path;
     path = val;
     val = _;
   } else if (typeof path !== 'string') {
@@ -937,9 +938,12 @@ Document.prototype.$set = function $set(path, val, type, options) {
         path = path._doc;
       }
     }
-
+    if(path == null){
+      let _ = path;
+       path = val;
+       val = _;
+     }
     prefix = val ? val + '.' : '';
-
     keys = Object.keys(path);
     const len = keys.length;
 
diff --git a/test/document.test.js b/test/document.test.js
index a96e19111e9..a60f273a267 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9931,4 +9931,63 @@ describe('document', function() {
       assert.ok(doc);
     });
   });
+  it('gh9880', function() {
+    const mongoose = require('mongoose');
+    const { Schema } = mongoose;
+    mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true, useUnifiedTopology: true});
+
+    return co(function*() {
+      const testSchema = new Schema({
+        prop:  String,
+        nestedProp: {
+          prop: String
+        }
+      });
+
+
+      const Test = mongoose.model('Test', testSchema);
+
+      new Test({
+        prop: 'Test',
+        nestedProp: null
+      }).save((err, doc) => {
+        console.log(doc.id)
+        console.log(doc.nestedProp)
+
+        // let's clone this document:
+        const clone = new Test({
+          prop: 'Test 2',
+          nestedProp: doc.nestedProp
+        })
+
+        // so far, so good:
+        console.log(clone.id) // 'cloned document id'
+        console.log(clone.nestedProp) // '{}'
+
+        // let's update the document:
+        Test.updateOne({
+          _id: doc._id
+        }, {
+          nestedProp: null
+        }, (err) => {
+
+          // ... and retrieve it
+          Test.findOne({
+            _id: doc._id
+          }, (err, updatedDoc) => {
+
+            // now, this is interesting:
+            console.log(updatedDoc.id) // 'document id'
+            console.log(updatedDoc.nestedProp) // 'MongooseDocument { null }'
+
+            // now this will throw a TypeError:
+            const failing = new Test({
+              prop: 'Test 3',
+              nestedProp: updatedDoc.nestedProp
+            });
+          });
+        });
+      });
+    });
+  });
 });

From c8fef00e17a381577cc9b0e70e1a2f28bf4c7686 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:06:10 -0500
Subject: [PATCH 1667/2348] fix: null value in nested document no longer causes
 typeerror

also removed some console.logs from another test
---
 lib/document.js             |  6 +++---
 test/document.test.js       | 29 +++++++++++------------------
 test/model.populate.test.js |  4 ++--
 3 files changed, 16 insertions(+), 23 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 2f886cbdf52..bb6ce50bc31 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -140,7 +140,6 @@ function Document(obj, fields, skipId, options) {
       });
     }
   }
-console.log('Hello????????');
   if (obj) {
     // Skip set hooks
     if (this.$__original_set) {
@@ -938,11 +937,12 @@ Document.prototype.$set = function $set(path, val, type, options) {
         path = path._doc;
       }
     }
-    if(path == null){
+    if (path == null) {
       let _ = path;
        path = val;
        val = _;
-     }
+    }
+
     prefix = val ? val + '.' : '';
     keys = Object.keys(path);
     const len = keys.length;
diff --git a/test/document.test.js b/test/document.test.js
index a60f273a267..8472d7803be 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9878,7 +9878,7 @@ describe('document', function() {
       assert.equal(ss.nested[0].toHexString(), updatedElID);
     });
   });
-  it('gh9884', function() {
+  it('gh9884', function(done) {
     return co(function*() {
 
       const obi = new Schema({
@@ -9931,38 +9931,31 @@ describe('document', function() {
       assert.ok(doc);
     });
   });
-  it('gh9880', function() {
-    const mongoose = require('mongoose');
-    const { Schema } = mongoose;
-    mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true, useUnifiedTopology: true});
-
-    return co(function*() {
+  it('gh9880', function(done) {
       const testSchema = new Schema({
         prop:  String,
         nestedProp: {
           prop: String
         }
       });
-
-
-      const Test = mongoose.model('Test', testSchema);
+      const Test = db.model('Test', testSchema);
 
       new Test({
         prop: 'Test',
         nestedProp: null
       }).save((err, doc) => {
-        console.log(doc.id)
-        console.log(doc.nestedProp)
+        // console.log(doc.id);
+        // console.log(doc.nestedProp);
 
         // let's clone this document:
         const clone = new Test({
           prop: 'Test 2',
           nestedProp: doc.nestedProp
-        })
+        });
 
         // so far, so good:
-        console.log(clone.id) // 'cloned document id'
-        console.log(clone.nestedProp) // '{}'
+        // console.log(clone.id); // 'cloned document id'
+        // console.log(clone.nestedProp); // '{}'
 
         // let's update the document:
         Test.updateOne({
@@ -9977,8 +9970,8 @@ describe('document', function() {
           }, (err, updatedDoc) => {
 
             // now, this is interesting:
-            console.log(updatedDoc.id) // 'document id'
-            console.log(updatedDoc.nestedProp) // 'MongooseDocument { null }'
+            // console.log(updatedDoc.id); // 'document id'
+            // console.log(updatedDoc.nestedProp); // 'MongooseDocument { null }'
 
             // now this will throw a TypeError:
             const failing = new Test({
@@ -9986,8 +9979,8 @@ describe('document', function() {
               nestedProp: updatedDoc.nestedProp
             });
           });
+        done();
         });
       });
-    });
   });
 });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index def9145cde2..da3a8b44d01 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9898,7 +9898,7 @@ describe('model: populate:', function() {
       ];
       const books = yield Books.aggregate(aggregateOptions).exec();
 
-      console.log('books = ' + util.inspect(books, false, null, true));
+      // console.log('books = ' + util.inspect(books, false, null, true));
 
       const populateOptions = [{
         path: 'tags.author',
@@ -9907,7 +9907,7 @@ describe('model: populate:', function() {
       }];
 
       const populatedBooks = yield Books.populate(books, populateOptions);
-      console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true));
+      // console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true));
       assert.ok(!Array.isArray(populatedBooks[0].tags[0].author));
     });
   });

From 7560ae017d982b260781ad29794272ca594d2f24 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:22:33 -0500
Subject: [PATCH 1668/2348] fixed spacing issues

---
 lib/document.js             |  4 +-
 test/document.test.js       | 86 ++++++++++++++++++-------------------
 test/model.populate.test.js |  2 +-
 3 files changed, 46 insertions(+), 46 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index bb6ce50bc31..51147cc3ae8 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -939,8 +939,8 @@ Document.prototype.$set = function $set(path, val, type, options) {
     }
     if (path == null) {
       let _ = path;
-       path = val;
-       val = _;
+      path = val;
+      val = _;
     }
 
     prefix = val ? val + '.' : '';
diff --git a/test/document.test.js b/test/document.test.js
index 8472d7803be..1dfff6d71f5 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9878,7 +9878,7 @@ describe('document', function() {
       assert.equal(ss.nested[0].toHexString(), updatedElID);
     });
   });
-  it('gh9884', function(done) {
+  it('gh9884', function() {
     return co(function*() {
 
       const obi = new Schema({
@@ -9932,55 +9932,55 @@ describe('document', function() {
     });
   });
   it('gh9880', function(done) {
-      const testSchema = new Schema({
-        prop:  String,
-        nestedProp: {
-          prop: String
-        }
+    const testSchema = new Schema({
+      prop:  String,
+      nestedProp: {
+        prop: String
+      }
+    });
+    const Test = db.model('Test', testSchema);
+
+    new Test({
+      prop: 'Test',
+      nestedProp: null
+    }).save((err, doc) => {
+      // console.log(doc.id);
+      // console.log(doc.nestedProp);
+
+      // let's clone this document:
+      const clone = new Test({
+        prop: 'Test 2',
+        nestedProp: doc.nestedProp
       });
-      const Test = db.model('Test', testSchema);
 
-      new Test({
-        prop: 'Test',
-        nestedProp: null
-      }).save((err, doc) => {
-        // console.log(doc.id);
-        // console.log(doc.nestedProp);
-
-        // let's clone this document:
-        const clone = new Test({
-          prop: 'Test 2',
-          nestedProp: doc.nestedProp
-        });
+      // so far, so good:
+      // console.log(clone.id); // 'cloned document id'
+      // console.log(clone.nestedProp); // '{}'
 
-        // so far, so good:
-        // console.log(clone.id); // 'cloned document id'
-        // console.log(clone.nestedProp); // '{}'
+      // let's update the document:
+      Test.updateOne({
+        _id: doc._id
+      }, {
+        nestedProp: null
+      }, (err) => {
 
-        // let's update the document:
-        Test.updateOne({
+        // ... and retrieve it
+        Test.findOne({
           _id: doc._id
-        }, {
-          nestedProp: null
-        }, (err) => {
-
-          // ... and retrieve it
-          Test.findOne({
-            _id: doc._id
-          }, (err, updatedDoc) => {
-
-            // now, this is interesting:
-            // console.log(updatedDoc.id); // 'document id'
-            // console.log(updatedDoc.nestedProp); // 'MongooseDocument { null }'
-
-            // now this will throw a TypeError:
-            const failing = new Test({
-              prop: 'Test 3',
-              nestedProp: updatedDoc.nestedProp
-            });
+        }, (err, updatedDoc) => {
+
+          // now, this is interesting:
+          // console.log(updatedDoc.id); // 'document id'
+          // console.log(updatedDoc.nestedProp); // 'MongooseDocument { null }'
+
+          // now this will throw a TypeError:
+          const failing = new Test({
+            prop: 'Test 3',
+            nestedProp: updatedDoc.nestedProp
           });
-        done();
         });
+        done();
       });
+    });
   });
 });
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index da3a8b44d01..fcd0e57bd0e 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9870,7 +9870,7 @@ describe('model: populate:', function() {
     });
   });
   it('gh-9833', function() {
-    const util = require('util');
+    // const util = require('util');
     const Books = db.model('books', new Schema({ name: String, tags: [{ type: Schema.Types.ObjectId, ref: 'tags' }] }));
     const Tags = db.model('tags', new Schema({ author: Schema.Types.ObjectId }));
     const Authors = db.model('authors', new Schema({ name: String }));

From 74130bcdeb5e139dc3a8d13f5c0068fad292550d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:26:10 -0500
Subject: [PATCH 1669/2348] another attempt to get all the linter errors

---
 test/document.test.js | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 1dfff6d71f5..20566793bd6 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9933,7 +9933,7 @@ describe('document', function() {
   });
   it('gh9880', function(done) {
     const testSchema = new Schema({
-      prop:  String,
+      prop: String,
       nestedProp: {
         prop: String
       }
@@ -9948,10 +9948,10 @@ describe('document', function() {
       // console.log(doc.nestedProp);
 
       // let's clone this document:
-      const clone = new Test({
-        prop: 'Test 2',
-        nestedProp: doc.nestedProp
-      });
+      // const clone = new Test({
+      //   prop: 'Test 2',
+      //   nestedProp: doc.nestedProp
+      // });
 
       // so far, so good:
       // console.log(clone.id); // 'cloned document id'
@@ -9962,7 +9962,7 @@ describe('document', function() {
         _id: doc._id
       }, {
         nestedProp: null
-      }, (err) => {
+      }, (/* err */) => {
 
         // ... and retrieve it
         Test.findOne({
@@ -9974,10 +9974,10 @@ describe('document', function() {
           // console.log(updatedDoc.nestedProp); // 'MongooseDocument { null }'
 
           // now this will throw a TypeError:
-          const failing = new Test({
+         /* const failing = new Test({
             prop: 'Test 3',
             nestedProp: updatedDoc.nestedProp
-          });
+          }); */
         });
         done();
       });

From 694ad10cb6cf1f1bc6f7ff02edc7de9f96ff10e6 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:29:37 -0500
Subject: [PATCH 1670/2348] linter fixes

---
 test/document.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 20566793bd6..456ade4f052 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9967,14 +9967,14 @@ describe('document', function() {
         // ... and retrieve it
         Test.findOne({
           _id: doc._id
-        }, (err, updatedDoc) => {
+        }, (/* err, */ updatedDoc) => {
 
           // now, this is interesting:
-          // console.log(updatedDoc.id); // 'document id'
+          updatedDoc.id; // 'document id'
           // console.log(updatedDoc.nestedProp); // 'MongooseDocument { null }'
 
           // now this will throw a TypeError:
-         /* const failing = new Test({
+          /* const failing = new Test({
             prop: 'Test 3',
             nestedProp: updatedDoc.nestedProp
           }); */

From 567e8d128c5e191b5e162a779d2b23eacd9e8588 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:37:48 -0500
Subject: [PATCH 1671/2348] Update document.test.js

---
 test/document.test.js | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 456ade4f052..4f18d47410a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9944,40 +9944,40 @@ describe('document', function() {
       prop: 'Test',
       nestedProp: null
     }).save((err, doc) => {
-      // console.log(doc.id);
-      // console.log(doc.nestedProp);
+      doc.id;
+      doc.nestedProp;
 
       // let's clone this document:
-      // const clone = new Test({
-      //   prop: 'Test 2',
-      //   nestedProp: doc.nestedProp
-      // });
+      const clone = new Test({
+        prop: 'Test 2',
+        nestedProp: doc.nestedProp
+      });
 
       // so far, so good:
-      // console.log(clone.id); // 'cloned document id'
-      // console.log(clone.nestedProp); // '{}'
+      clone.id; // 'cloned document id'
+      clone.nestedProp; // '{}'
 
       // let's update the document:
       Test.updateOne({
         _id: doc._id
       }, {
         nestedProp: null
-      }, (/* err */) => {
+      }, (err) => {
 
         // ... and retrieve it
         Test.findOne({
           _id: doc._id
-        }, (/* err, */ updatedDoc) => {
+        }, ( err, updatedDoc) => {
 
           // now, this is interesting:
           updatedDoc.id; // 'document id'
-          // console.log(updatedDoc.nestedProp); // 'MongooseDocument { null }'
+          updatedDoc.nestedProp; // 'MongooseDocument { null }'
 
           // now this will throw a TypeError:
-          /* const failing = new Test({
+          const failing = new Test({
             prop: 'Test 3',
             nestedProp: updatedDoc.nestedProp
-          }); */
+          });
         });
         done();
       });

From f9aa18a0eed11874472c81abbf34becd3704a36f Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:42:06 -0500
Subject: [PATCH 1672/2348] Update document.js

---
 test/document.test.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 4f18d47410a..6572722d09c 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9967,9 +9967,10 @@ describe('document', function() {
         // ... and retrieve it
         Test.findOne({
           _id: doc._id
-        }, ( err, updatedDoc) => {
+        }, (err, updatedDoc) => {
 
           // now, this is interesting:
+          err;
           updatedDoc.id; // 'document id'
           updatedDoc.nestedProp; // 'MongooseDocument { null }'
 
@@ -9978,6 +9979,7 @@ describe('document', function() {
             prop: 'Test 3',
             nestedProp: updatedDoc.nestedProp
           });
+          failing;
         });
         done();
       });

From 4c21e91bce70da8162a7b6a7f10ce7db7a758f2b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 14:43:59 -0500
Subject: [PATCH 1673/2348] Update document.test.js

---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 6572722d09c..bfbe6b61a9f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9963,7 +9963,7 @@ describe('document', function() {
       }, {
         nestedProp: null
       }, (err) => {
-
+        err;
         // ... and retrieve it
         Test.findOne({
           _id: doc._id

From bb09e65a0b23efb150838bc3953bba9539ec928d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 17:16:48 -0500
Subject: [PATCH 1674/2348] Update document.test.js

---
 test/document.test.js | 47 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index a96e19111e9..3d1bd52e391 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9931,4 +9931,51 @@ describe('document', function() {
       assert.ok(doc);
     });
   });
+  it('gh-9885', function() {
+    const SubSchema = new Schema({
+      myValue: {
+        type: String
+      }
+    }, {});
+    SubSchema.pre('remove', function(){
+      console.log('Subdoc got removed!');
+    });
+
+    const thisSchema = new Schema({
+      foo: {
+        type: String,
+        required: true
+      },
+      mySubdoc: {
+        type: [SubSchema],
+        required: true
+      }
+    }, {minimize: false, collection: 'test'});
+
+    const Model = db.model('TestModel',thisSchema);
+    const test = co(function*(){
+      yield Model.deleteMany({}); // remove all existing documents
+      const newModel = {
+        foo: 'bar',
+        mySubdoc: [{myValue: 'some value'}]
+      };
+      const document = yield Model.create(newModel);
+      console.log('Created Document');
+      console.log('document', document);
+      console.log('Removing subDocument');
+      document.mySubdoc[0].remove();
+      console.log('Saving document');
+      yield document.save().catch((error) => {
+        console.error(error);
+        process.exit(1);
+      });
+    console.log('document: ',document);
+    console.log(`Notice that SubSchema.pre('remove') never ran`);
+    });
+    const main = co(function*(){
+      yield test;
+      process.exit(0);
+    });
+    main;
+  });
 });

From edb58f0cd99396fcf4fec2e2c0fc274f30b7a7dc Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 17:20:03 -0500
Subject: [PATCH 1675/2348] Update document.test.js

have to leave failing there as the linter will complain its unused.
---
 test/document.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index bfbe6b61a9f..7c3c0ab3053 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9980,8 +9980,8 @@ describe('document', function() {
             nestedProp: updatedDoc.nestedProp
           });
           failing;
+          done();
         });
-        done();
       });
     });
   });

From a031543e4cbe2bdade12607ab3d4840ca56fd55a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 2 Feb 2021 18:02:28 -0500
Subject: [PATCH 1676/2348] for work tomorrow

---
 test/document.test.js | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 3d1bd52e391..2b03e4d8744 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9937,9 +9937,9 @@ describe('document', function() {
         type: String
       }
     }, {});
-    SubSchema.pre('remove', function(){
+    SubSchema.pre('remove', co.wrap(function*(){
       console.log('Subdoc got removed!');
-    });
+    }));
 
     const thisSchema = new Schema({
       foo: {
@@ -9965,17 +9965,19 @@ describe('document', function() {
       console.log('Removing subDocument');
       document.mySubdoc[0].remove();
       console.log('Saving document');
-      yield document.save().catch((error) => {
+      // had to remove yield for the rest to execute but now saying error.
+      document.save().catch((error) => {
         console.error(error);
         process.exit(1);
       });
-    console.log('document: ',document);
+    console.log('document: ', document);
     console.log(`Notice that SubSchema.pre('remove') never ran`);
     });
-    const main = co(function*(){
-      yield test;
-      process.exit(0);
+    const main = co.wrap(function*(){
+      return yield test;
+    });
+    main(true).then(function(){
+      process.exit(1);
     });
-    main;
   });
 });

From b1d2f910516045bc5a2037723acd38448eebca9c Mon Sep 17 00:00:00 2001
From: Joey Cheng <jooeycheng@gmail.com>
Date: Wed, 3 Feb 2021 13:45:07 +0800
Subject: [PATCH 1677/2348] Upgrade mongodb driver to 3.6.4

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 64ef253ecd8..e5ff110aa30 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.3",
+    "mongodb": "3.6.4",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.3",

From a5fb467563f8b47e335645cb4da3515986c16f4d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaras=C5=82a=C5=AD=20Viktor=C4=8Dyk?= <ugzuzg@gmail.com>
Date: Tue, 2 Feb 2021 16:26:52 -0100
Subject: [PATCH 1678/2348] fix(index.d.ts): reorder create typings to allow
 array desctructuring

---
 index.d.ts                | 4 ++--
 test/typescript/create.ts | 9 ++++++++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 8706df16808..dc2e64809b7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -630,11 +630,11 @@ declare module 'mongoose' {
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
 
     /** Creates a new document or documents */
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
     create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
     create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: T) => void): void;
     create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: T[]) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: T) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,
diff --git a/test/typescript/create.ts b/test/typescript/create.ts
index c20f56cc308..cb76ce45172 100644
--- a/test/typescript/create.ts
+++ b/test/typescript/create.ts
@@ -18,4 +18,11 @@ Test.create({ name: 'test' }, { name: 'test2' }).then((docs: ITest[]) => console
 Test.insertMany({ name: 'test' }).then((doc: ITest) => console.log(doc.name));
 Test.insertMany([{ name: 'test' }], { session: null }).then((docs: ITest[]) => console.log(docs[0].name));
 
-Test.create([{ name: 'test' }], { validateBeforeSave: true }).then((docs: ITest[]) => console.log(docs[0].name));
\ No newline at end of file
+Test.create([{ name: 'test' }], { validateBeforeSave: true }).then((docs: ITest[]) => console.log(docs[0].name));
+
+(async() => {
+  const [t1] = await Test.create([{ name: 'test' }]);
+  const [t2, t3, t4] = await Test.create({ name: 'test' }, { name: 'test' }, { name: 'test' });
+  (await Test.create([{ name: 'test' }]))[0];
+  (await Test.create({ name: 'test' }))._id;
+})();

From 2665940c64e89cc6248cee9ef753ec1f0baf911a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Feb 2021 10:49:35 -0500
Subject: [PATCH 1679/2348] style: quick cleanup

---
 test/document.test.js | 18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 7c3c0ab3053..9cfc4fb3210 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9931,6 +9931,7 @@ describe('document', function() {
       assert.ok(doc);
     });
   });
+
   it('gh9880', function(done) {
     const testSchema = new Schema({
       prop: String,
@@ -9953,33 +9954,20 @@ describe('document', function() {
         nestedProp: doc.nestedProp
       });
 
-      // so far, so good:
-      clone.id; // 'cloned document id'
-      clone.nestedProp; // '{}'
-
-      // let's update the document:
       Test.updateOne({
         _id: doc._id
       }, {
         nestedProp: null
       }, (err) => {
-        err;
-        // ... and retrieve it
+        assert.ifError(err);
         Test.findOne({
           _id: doc._id
         }, (err, updatedDoc) => {
-
-          // now, this is interesting:
-          err;
-          updatedDoc.id; // 'document id'
-          updatedDoc.nestedProp; // 'MongooseDocument { null }'
-
-          // now this will throw a TypeError:
+          assert.ifError(err);
           const failing = new Test({
             prop: 'Test 3',
             nestedProp: updatedDoc.nestedProp
           });
-          failing;
           done();
         });
       });

From 0d88bb6ada6edc96899bc835808426e8d529717f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Feb 2021 10:50:30 -0500
Subject: [PATCH 1680/2348] style: get rid of console.logs

---
 test/model.populate.test.js | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index fcd0e57bd0e..97871f1ac92 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9870,7 +9870,6 @@ describe('model: populate:', function() {
     });
   });
   it('gh-9833', function() {
-    // const util = require('util');
     const Books = db.model('books', new Schema({ name: String, tags: [{ type: Schema.Types.ObjectId, ref: 'tags' }] }));
     const Tags = db.model('tags', new Schema({ author: Schema.Types.ObjectId }));
     const Authors = db.model('authors', new Schema({ name: String }));
@@ -9898,8 +9897,6 @@ describe('model: populate:', function() {
       ];
       const books = yield Books.aggregate(aggregateOptions).exec();
 
-      // console.log('books = ' + util.inspect(books, false, null, true));
-
       const populateOptions = [{
         path: 'tags.author',
         model: 'authors',
@@ -9907,7 +9904,6 @@ describe('model: populate:', function() {
       }];
 
       const populatedBooks = yield Books.populate(books, populateOptions);
-      // console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true));
       assert.ok(!Array.isArray(populatedBooks[0].tags[0].author));
     });
   });

From 81fa1df152a42ede55ce69ce12413d72bf9b985f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Feb 2021 10:57:44 -0500
Subject: [PATCH 1681/2348] style: fix lint re: #9891

---
 lib/document.js       | 4 ++--
 test/document.test.js | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 51147cc3ae8..f671ae4ee3d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -925,7 +925,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
   }
 
   if (path == null) {
-    let _ = path;
+    const _ = path;
     path = val;
     val = _;
   } else if (typeof path !== 'string') {
@@ -938,7 +938,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
       }
     }
     if (path == null) {
-      let _ = path;
+      const _ = path;
       path = val;
       val = _;
     }
diff --git a/test/document.test.js b/test/document.test.js
index 9cfc4fb3210..6a86a1365fb 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9949,7 +9949,7 @@ describe('document', function() {
       doc.nestedProp;
 
       // let's clone this document:
-      const clone = new Test({
+      new Test({
         prop: 'Test 2',
         nestedProp: doc.nestedProp
       });
@@ -9964,7 +9964,7 @@ describe('document', function() {
           _id: doc._id
         }, (err, updatedDoc) => {
           assert.ifError(err);
-          const failing = new Test({
+          new Test({
             prop: 'Test 3',
             nestedProp: updatedDoc.nestedProp
           });

From f1f2efc1c20947f33792c01daa3eb9a1961eaf1c Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 3 Feb 2021 14:02:30 -0500
Subject: [PATCH 1682/2348] fix: pre-remove hooks will now be called for
 subdocuments

---
 lib/document.js          |  5 -----
 lib/types/embedded.js    |  9 +++++----
 lib/types/subdocument.js |  1 -
 test/document.test.js    | 32 +++++++++++---------------------
 4 files changed, 16 insertions(+), 31 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 7bf725fdeef..6c14f869db2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2256,7 +2256,6 @@ function _getPathsToValidate(doc) {
   const skipSchemaValidators = {};
 
   _evaluateRequiredFunctions(doc);
-
   // only validate required fields when necessary
   let paths = new Set(Object.keys(doc.$__.activePaths.states.require).filter(function(path) {
     if (!doc.$__isSelected(path) && !doc.isModified(path)) {
@@ -2340,7 +2339,6 @@ function _getPathsToValidate(doc) {
     }
   }
 
-
   for (const path of paths) {
     // Single nested paths (paths embedded under single nested subdocs) will
     // be validated on their own when we call `validate()` on the subdoc itself.
@@ -2434,11 +2432,9 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     pathDetails[0].filter((path) => this.isModified(path)) :
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
-
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }
-
   if (paths.length === 0) {
     return process.nextTick(function() {
       const error = _complete();
@@ -2606,7 +2602,6 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }
-
   const validating = {};
 
   paths.forEach(function(path) {
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 531128d404b..5bcdc412f06 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -201,6 +201,9 @@ function registerRemoveListener(sub) {
  */
 
 EmbeddedDocument.prototype.$__remove = function(cb) {
+  if (cb == null) {
+    return;
+  }
   return cb(null, this);
 };
 
@@ -218,7 +221,7 @@ EmbeddedDocument.prototype.remove = function(options, fn) {
     options = undefined;
   }
   if (!this.__parentArray || (options && options.noop)) {
-    fn && fn(null);
+    this.$__remove(fn);
     return this;
   }
 
@@ -234,9 +237,7 @@ EmbeddedDocument.prototype.remove = function(options, fn) {
     registerRemoveListener(this);
   }
 
-  if (fn) {
-    fn(null);
-  }
+  this.$__remove(fn);
 
   return this;
 };
diff --git a/lib/types/subdocument.js b/lib/types/subdocument.js
index bc37342467c..182fa229f13 100644
--- a/lib/types/subdocument.js
+++ b/lib/types/subdocument.js
@@ -255,7 +255,6 @@ Subdocument.prototype.remove = function(options, callback) {
     callback = options;
     options = null;
   }
-
   registerRemoveListener(this);
 
   // If removing entire doc, no need to remove subdoc
diff --git a/test/document.test.js b/test/document.test.js
index 2b03e4d8744..f2e2cd5227a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9931,16 +9931,18 @@ describe('document', function() {
       assert.ok(doc);
     });
   });
-  it('gh-9885', function() {
+  it('Makes sure pre remove hook is executed gh-9885', function() {
+    const tracker = new assert.CallTracker();
     const SubSchema = new Schema({
       myValue: {
         type: String
       }
     }, {});
-    SubSchema.pre('remove', co.wrap(function*(){
-      console.log('Subdoc got removed!');
-    }));
-
+    let count = 0;
+    SubSchema.pre('remove', function(next) {
+      count++;
+      next();
+    });
     const thisSchema = new Schema({
       foo: {
         type: String,
@@ -9953,31 +9955,19 @@ describe('document', function() {
     }, {minimize: false, collection: 'test'});
 
     const Model = db.model('TestModel',thisSchema);
-    const test = co(function*(){
+
+    return co(function*() {
       yield Model.deleteMany({}); // remove all existing documents
       const newModel = {
         foo: 'bar',
         mySubdoc: [{myValue: 'some value'}]
       };
       const document = yield Model.create(newModel);
-      console.log('Created Document');
-      console.log('document', document);
-      console.log('Removing subDocument');
       document.mySubdoc[0].remove();
-      console.log('Saving document');
-      // had to remove yield for the rest to execute but now saying error.
-      document.save().catch((error) => {
+      yield document.save().catch((error) => {
         console.error(error);
-        process.exit(1);
       });
-    console.log('document: ', document);
-    console.log(`Notice that SubSchema.pre('remove') never ran`);
-    });
-    const main = co.wrap(function*(){
-      return yield test;
-    });
-    main(true).then(function(){
-      process.exit(1);
+      assert.equal(count,1);
     });
   });
 });

From aefd83815c0b055c86612b18448e9d1c0bddf3c9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Feb 2021 14:05:09 -0500
Subject: [PATCH 1683/2348] chore: release 5.11.15

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 2e1d6500294..91130da0e10 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.11.15 / 2021-02-03
+====================
+ * fix(document): fix issues with `isSelected` as an path in a nested schema #9884 #9873 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(index.d.ts): better support for `SchemaDefinition` generics when creating schema #9863 #9862 #9789
+ * fix(index.d.ts): allow required function in array definition #9888 [Ugzuzg](https://github.com/Ugzuzg)
+ * fix(index.d.ts): reorder create typings to allow array desctructuring #9890 [Ugzuzg](https://github.com/Ugzuzg)
+ * fix(index.d.ts): add missing overload to Model.validate #9878 #9877 [jonamat](https://github.com/jonamat)
+ * fix(index.d.ts): throw compiler error if schema says path is a String, but interface says path is a number #9857
+ * fix(index.d.ts): make `Query` a class, allow calling `Query#where()` with object argument and with no arguments #9856
+ * fix(index.d.ts): support calling `Schema#pre()` and `Schema#post()` with options and array of hooked function names #9844
+ * docs(faq): mention other debug options than console #9887 [dandv](https://github.com/dandv)
+ * docs(connections): clarify that Mongoose can emit 'error' both during initial connection and after initial connection #9853
+
 5.11.14 / 2021-01-28
 ====================
  * fix(populate): avoid inferring `justOne` from parent when populating a POJO with a manually populated path #9833 [IslandRhythms](https://github.com/IslandRhythms)
diff --git a/package.json b/package.json
index 64ef253ecd8..9af7dac12f9 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.14",
+  "version": "5.11.15",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From f79e9a71ee5f092aedf1a03d05d3c99cf423e6ef Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 3 Feb 2021 14:05:58 -0500
Subject: [PATCH 1684/2348] fix linter complaints

---
 test/document.test.js | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index f2e2cd5227a..6a9c50c13c1 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9932,7 +9932,6 @@ describe('document', function() {
     });
   });
   it('Makes sure pre remove hook is executed gh-9885', function() {
-    const tracker = new assert.CallTracker();
     const SubSchema = new Schema({
       myValue: {
         type: String
@@ -9952,22 +9951,22 @@ describe('document', function() {
         type: [SubSchema],
         required: true
       }
-    }, {minimize: false, collection: 'test'});
+    }, { minimize: false, collection: 'test' });
 
-    const Model = db.model('TestModel',thisSchema);
+    const Model = db.model('TestModel', thisSchema);
 
     return co(function*() {
       yield Model.deleteMany({}); // remove all existing documents
       const newModel = {
         foo: 'bar',
-        mySubdoc: [{myValue: 'some value'}]
+        mySubdoc: [{ myValue: 'some value' }]
       };
       const document = yield Model.create(newModel);
       document.mySubdoc[0].remove();
       yield document.save().catch((error) => {
         console.error(error);
       });
-      assert.equal(count,1);
+      assert.equal(count, 1);
     });
   });
 });

From 3b9be6828b33205b5a76c619155cda34be61cdcf Mon Sep 17 00:00:00 2001
From: ggurkal <giraygurkal@gmail.com>
Date: Wed, 3 Feb 2021 23:14:09 +0100
Subject: [PATCH 1685/2348] feat(typescript): improved types

---
 index.d.ts                 | 174 ++++++++++++++++++++-----------------
 test/typescript/queries.ts |  14 ++-
 2 files changed, 104 insertions(+), 84 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e349d0cd652..11a4e638ed7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,10 +99,10 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
-  export function model<T extends Document, U extends Model<T>>(
+  export function model<T extends Document, TQueryHelpers = {}>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
+  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
     name: string,
-    schema?: Schema<T, U>,
+    schema?: Schema<T, U, TQueryHelpers>,
     collection?: string,
     skipInit?: boolean
   ): U;
@@ -244,9 +244,9 @@ declare module 'mongoose' {
 
     /** Defines or retrieves a model. */
     model<T extends Document>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
-    model<T extends Document, U extends Model<T>>(
+    model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
       name: string,
-      schema?: Schema<T, U>,
+      schema?: Schema<T, U, TQueryHelpers>,
       collection?: string,
       skipInit?: boolean
     ): U;
@@ -590,9 +590,19 @@ declare module 'mongoose' {
     validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
   }
 
+  type CreateDoc<T> = {
+    [P in keyof T as
+      T[P] extends Function
+      ? never
+      : P
+    ]: T[P] extends infer R
+      ? CreateDoc<R>
+      : T[P];
+  };
+
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document> extends NodeJS.EventEmitter {
+  interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
@@ -622,19 +632,19 @@ declare module 'mongoose' {
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): Query<number, T>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
+    count(callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): Query<number, T>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
+    countDocuments(callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
 
     /** Creates a new document or documents */
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
-    create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: T[]) => void): void;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: T) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(docs: CreateDoc<T | DocumentDefinition<T> | DocContents>[], options?: SaveOptions): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(doc: CreateDoc<T | DocumentDefinition<T> | DocContents>): Promise<T>;
+    create<DocContents = T | DocumentDefinition<T>>(...docs: CreateDoc<T | DocumentDefinition<T> | DocContents>[]): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(docs: CreateDoc<T | DocumentDefinition<T> | DocContents>[], callback: (err: CallbackError, docs: T[]) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: CreateDoc<T | DocumentDefinition<T> | DocContents>, callback: (err: CallbackError, doc: T) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,
@@ -659,14 +669,14 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T>;
+    deleteMany(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T, TQueryHelpers>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T>;
+    deleteOne(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T, TQueryHelpers>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
@@ -687,10 +697,10 @@ declare module 'mongoose' {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T, TQueryHelpers>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
@@ -760,7 +770,7 @@ declare module 'mongoose' {
 
     /** Adds a `$where` clause to this query */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): Query<Array<T>, T>;
+    $where(argument: string | Function): Query<Array<T>, T, TQueryHelpers>;
 
     /** Registered discriminators for this model. */
     discriminators: { [name: string]: Model<any> } | undefined;
@@ -772,10 +782,10 @@ declare module 'mongoose' {
     discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T, TQueryHelpers>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
 
     /**
      * Returns true if at least one document exists in the database that matches
@@ -785,37 +795,37 @@ declare module 'mongoose' {
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: T[]) => void): Query<Array<T>, T>;
-    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T>;
+    find(callback?: (err: any, docs: T[]) => void): Query<Array<T>, T, TQueryHelpers> & TQueryHelpers;
+    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T, TQueryHelpers> & TQueryHelpers;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T, TQueryHelpers> & TQueryHelpers;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
-    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T, TQueryHelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T, TQueryHelpers>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T, TQueryHelpers>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T, TQueryHelpers>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
@@ -823,10 +833,10 @@ declare module 'mongoose' {
       callback?: (err: any, res: any) => void
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: CallbackError) => void): Query<any, T>;
+    remove(filter?: any, callback?: (err: CallbackError) => void): Query<any, T, TQueryHelpers>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T, TQueryHelpers>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -835,18 +845,18 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T, TQueryHelpers>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T, TQueryHelpers>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T, TQueryHelpers>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
-    where(path: string, val?: any): Query<Array<T>, T>;
-    where(obj: object): Query<Array<T>, T>;
-    where(): Query<Array<T>, T>;
+    where(path: string, val?: any): Query<Array<T>, T, TQueryHelpers>;
+    where(obj: object): Query<Array<T>, T, TQueryHelpers>;
+    where(): Query<Array<T>, T, TQueryHelpers>;
   }
 
   interface QueryOptions {
@@ -1046,7 +1056,7 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, TQueryHelpers = {}, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1149,7 +1159,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: any;
+    query: TQueryHelpers;
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
@@ -1794,7 +1804,7 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false };
 
-  class Query<ResultType, DocType extends Document> {
+  class Query<ResultType, DocType extends Document, THelpers = {}> {
     _mongooseOptions: MongooseQueryOptions;
 
     /** Executes the query */
@@ -1804,7 +1814,7 @@ declare module 'mongoose' {
     exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
 
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): Query<Array<DocType>, DocType>;
+    $where(argument: string | Function): Query<Array<DocType>, DocType, THelpers>;
 
     /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     all(val: Array<any>): this;
@@ -1820,7 +1830,7 @@ declare module 'mongoose' {
     box(val: any): this;
     box(lower: number[], upper: number[]): this;
 
-    cast(model: Model<any> | null, obj: any): UpdateQuery<DocType>;
+    cast(model: Model<any, THelpers> | null, obj: any): UpdateQuery<DocType>;
 
     /**
      * Executes the query returning a `Promise` which will be
@@ -1840,12 +1850,12 @@ declare module 'mongoose' {
     comment(val: string): this;
 
     /** Specifies this query as a `count` query. */
-    count(callback?: (err: any, count: number) => void): Query<number, DocType>;
-    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
+    count(callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
+    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
 
     /** Specifies this query as a `countDocuments` query. */
-    countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType>;
-    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType>;
+    countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
+    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
 
     /**
      * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
@@ -1858,17 +1868,17 @@ declare module 'mongoose' {
      * remove, except it deletes _every_ document that matches `filter` in the
      * collection, regardless of the value of `single`.
      */
-    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
+    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as a `deleteOne()` operation. Works like
      * remove, except it deletes at most one document regardless of the `single`
      * option.
      */
-    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
+    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType>;
+    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType, THelpers>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     // eslint-disable-next-line @typescript-eslint/ban-types
@@ -1887,7 +1897,7 @@ declare module 'mongoose' {
     equals(val: any): this;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
 
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
@@ -1902,31 +1912,31 @@ declare module 'mongoose' {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType>;
-    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): Query<Array<DocType>, DocType>;
+    find(callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers> & THelpers;
+    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers> & THelpers;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers> & THelpers;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
-    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): Query<DocType | null, DocType>;
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): Query<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType>;
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
-    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType, THelpers>;
+    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType, THelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
 
     /** Specifies a `$geometry` condition */
     geometry(object: { type: string, coordinates: any[] }): this;
@@ -1975,7 +1985,7 @@ declare module 'mongoose' {
     j(val: boolean | null): this;
 
     /** Sets the lean option. */
-    lean<LeanResultType = LeanDocumentOrArray<ResultType>>(val?: boolean | any): Query<LeanResultType, DocType>;
+    lean<LeanResultType = LeanDocumentOrArray<ResultType>>(val?: boolean | any): Query<LeanResultType, DocType, THelpers>;
 
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
@@ -1992,7 +2002,7 @@ declare module 'mongoose' {
      * Runs a function `fn` and treats the return value of `fn` as the new value
      * for the query to resolve to.
      */
-    map<MappedType>(fn: (doc: DocType) => MappedType): Query<MappedType, DocType>;
+    map<MappedType>(fn: (doc: DocType) => MappedType): Query<MappedType, DocType, THelpers>;
 
     /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     maxDistance(val: number): this;
@@ -2044,14 +2054,14 @@ declare module 'mongoose' {
      * This is handy for integrating with async/await, because `orFail()` saves you
      * an extra `if` statement to check if no document was found.
      */
-    orFail(err?: NativeError | (() => NativeError)): Query<NonNullable<ResultType>, DocType>;
+    orFail(err?: NativeError | (() => NativeError)): Query<NonNullable<ResultType>, DocType, THelpers>;
 
     /** Specifies a `$polygon` condition */
     polygon(...coordinatePairs: number[][]): this;
     polygon(path: string, ...coordinatePairs: number[][]): this;
 
     /** Specifies paths which should be populated with other documents. */
-    populate(path: string | any, select?: string | any, model?: string | Model<any>, match?: any): this;
+    populate(path: string | any, select?: string | any, model?: string | Model<any, THelpers>, match?: any): this;
     populate(options: PopulateOptions | Array<PopulateOptions>): this;
 
     /** Get/set the current projection (AKA fields). Pass `null` to remove the current projection. */
@@ -2072,14 +2082,14 @@ declare module 'mongoose' {
      * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
      * or [`deleteMany()`](#query_Query-deleteMany) instead.
      */
-    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType>;
+    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as a replaceOne() operation. Same as
      * `update()`, except MongoDB will replace the existing document and will
      * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
      */
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, DocType>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, DocType, THelpers>;
 
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;
@@ -2145,10 +2155,10 @@ declare module 'mongoose' {
     then: Promise<ResultType>['then'];
 
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
-    toConstructor(): new (...args: any[]) => Query<ResultType, DocType>;
+    toConstructor(): new (...args: any[]) => Query<ResultType, DocType, THelpers>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -2156,13 +2166,13 @@ declare module 'mongoose' {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 54807420698..a919b1195f4 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,6 +1,14 @@
 import { Schema, model, Document, Types, Query } from 'mongoose';
 
-const schema: Schema = new Schema({ name: { type: 'String' }, tags: [String] });
+interface QueryHelpers {
+  byName(name: string): Query<Array<ITest>, ITest, QueryHelpers>;
+}
+
+const schema: Schema<ITest, QueryHelpers> = new Schema({ name: { type: 'String' }, tags: [String] });
+
+schema.query.byName = function(name: string): Query<Array<ITest>, ITest, QueryHelpers> {
+  return this.find({ name });
+};
 
 interface ITest extends Document {
   name?: string;
@@ -9,7 +17,9 @@ interface ITest extends Document {
   tags?: string[];
 }
 
-const Test = model<ITest>('Test', schema);
+const Test = model<ITest, QueryHelpers>('Test', schema);
+
+Test.find().byName('test').orFail().exec().then(console.log);
 
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
 

From dc5da3c68c4d2d325157cc66c6eb6069d61e9b84 Mon Sep 17 00:00:00 2001
From: ggurkal <giraygurkal@gmail.com>
Date: Wed, 3 Feb 2021 23:48:18 +0100
Subject: [PATCH 1686/2348] refactor(typescript): omit internals when creating
 a document

---
 index.d.ts | 39 +++++++++++++++++++++++++--------------
 1 file changed, 25 insertions(+), 14 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 11a4e638ed7..adcce827b67 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -590,15 +590,26 @@ declare module 'mongoose' {
     validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
   }
 
-  type CreateDoc<T> = {
-    [P in keyof T as
-      T[P] extends Function
-      ? never
-      : P
-    ]: T[P] extends infer R
-      ? CreateDoc<R>
-      : T[P];
-  };
+  type CreateDoc<T> = Omit<
+    {
+      [P in keyof T as
+        T[P] extends Function
+        ? never
+        : P
+      ]: T[P] extends infer R
+        ? CreateDoc<R>
+        : T[P];
+    },
+    | '$locals'
+    | '$op'
+    | '$where'
+    | 'db'
+    | 'isNew'
+    | 'modelName'
+    | 'schema'
+    | 'baseModelName'
+    | 'errors'
+  >;
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
@@ -640,11 +651,11 @@ declare module 'mongoose' {
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
 
     /** Creates a new document or documents */
-    create<DocContents = T | DocumentDefinition<T>>(docs: CreateDoc<T | DocumentDefinition<T> | DocContents>[], options?: SaveOptions): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(doc: CreateDoc<T | DocumentDefinition<T> | DocContents>): Promise<T>;
-    create<DocContents = T | DocumentDefinition<T>>(...docs: CreateDoc<T | DocumentDefinition<T> | DocContents>[]): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(docs: CreateDoc<T | DocumentDefinition<T> | DocContents>[], callback: (err: CallbackError, docs: T[]) => void): void;
-    create<DocContents = T | DocumentDefinition<T>>(doc: CreateDoc<T | DocumentDefinition<T> | DocContents>, callback: (err: CallbackError, doc: T) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(docs: CreateDoc<DocContents>[], options?: SaveOptions): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(doc: CreateDoc<DocContents>): Promise<T>;
+    create<DocContents = T | DocumentDefinition<T>>(...docs: CreateDoc<DocContents>[]): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(docs: CreateDoc<DocContents>[], callback: (err: CallbackError, docs: T[]) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: CreateDoc<DocContents>, callback: (err: CallbackError, doc: T) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,

From bffca6ca20b152ff167e9b6d96910763ee8978d3 Mon Sep 17 00:00:00 2001
From: ggurkal <giraygurkal@gmail.com>
Date: Sun, 7 Feb 2021 12:12:53 +0100
Subject: [PATCH 1687/2348] chore(typescript): make prop infer specific to
 array and record

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index adcce827b67..42d2769fa65 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -596,8 +596,8 @@ declare module 'mongoose' {
         T[P] extends Function
         ? never
         : P
-      ]: T[P] extends infer R
-        ? CreateDoc<R>
+      ]: T[P] extends (Array<any> | Record<string, any>)
+        ? CreateDoc<T[P]>
         : T[P];
     },
     | '$locals'

From a068e44f4125dc50c4b844c0e25ff9ef8ed7e7d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 8 Feb 2021 16:58:56 -0500
Subject: [PATCH 1688/2348] fix(query): make `explain(false)` disable explain
 for backwards compat re: #9893

---
 lib/query.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index b115e6f17f7..21e19d205ed 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1397,9 +1397,11 @@ Query.prototype.setOptions = function(options, overwrite) {
 Query.prototype.explain = function(verbose) {
   if (arguments.length === 0) {
     this.options.explain = true;
-    return this;
+  } else if (verbose === false) {
+    delete this.options.explain;
+  } else {
+    this.options.explain = verbose;
   }
-  this.options.explain = verbose;
   return this;
 };
 

From fe8b97b1d0798e45792f5a7286265f60daefcb0d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 8 Feb 2021 17:25:47 -0500
Subject: [PATCH 1689/2348] fix: clean up deprecation warning issues from #9893

Re: https://github.com/mongodb/node-mongodb-native/pull/2735
---
 test/errors.validation.test.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 34c9c9f7127..69a32d020e3 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -243,16 +243,17 @@ describe('ValidationError', function() {
   });
 
   describe('when user code defines a r/o Error#toJSON', function() {
-    it('shoud not fail', function() {
+    it('shoud not fail', function(done) {
       const err = [];
       const child = require('child_process')
-        .fork('./test/isolated/project-has-error.toJSON.js', { silent: true });
+        .fork('./test/isolated/project-has-error.toJSON.js', ['--no-warnings'], { silent: true });
 
       child.stderr.on('data', function(buf) { err.push(buf); });
       child.on('exit', function(code) {
         const stderr = err.join('');
         assert.equal(stderr, '');
         assert.equal(code, 0);
+        done();
       });
     });
   });

From 425f35a45ce02297efd4463b022a25510686aaf7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 9 Feb 2021 12:22:22 -0500
Subject: [PATCH 1690/2348] fix(aggregate): automatically convert functions to
 strings when using `$function` operator

Fix #9897
---
 lib/aggregate.js                              |  4 +--
 ...tions.js => stringifyFunctionOperators.js} | 16 ++++++++++--
 test/helpers/aggregate.test.js                | 26 ++++++++++++++++---
 3 files changed, 39 insertions(+), 7 deletions(-)
 rename lib/helpers/aggregate/{stringifyAccumulatorOptions.js => stringifyFunctionOperators.js} (57%)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index 53131bff7f0..1f3251e6e29 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -8,7 +8,7 @@ const AggregationCursor = require('./cursor/AggregationCursor');
 const Query = require('./query');
 const applyGlobalMaxTimeMS = require('./helpers/query/applyGlobalMaxTimeMS');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
-const stringifyAccumulatorOptions = require('./helpers/aggregate/stringifyAccumulatorOptions');
+const stringifyFunctionOperators = require('./helpers/aggregate/stringifyFunctionOperators');
 const util = require('util');
 const utils = require('./utils');
 const read = Query.prototype.read;
@@ -983,7 +983,7 @@ Aggregate.prototype.exec = function(callback) {
 
   return promiseOrCallback(callback, cb => {
     prepareDiscriminatorPipeline(this);
-    stringifyAccumulatorOptions(this._pipeline);
+    stringifyFunctionOperators(this._pipeline);
 
     model.hooks.execPre('aggregate', this, error => {
       if (error) {
diff --git a/lib/helpers/aggregate/stringifyAccumulatorOptions.js b/lib/helpers/aggregate/stringifyFunctionOperators.js
similarity index 57%
rename from lib/helpers/aggregate/stringifyAccumulatorOptions.js
rename to lib/helpers/aggregate/stringifyFunctionOperators.js
index 7362514d8f5..124418efd68 100644
--- a/lib/helpers/aggregate/stringifyAccumulatorOptions.js
+++ b/lib/helpers/aggregate/stringifyFunctionOperators.js
@@ -1,6 +1,6 @@
 'use strict';
 
-module.exports = function stringifyAccumulatorOptions(pipeline) {
+module.exports = function stringifyFunctionOperators(pipeline) {
   if (!Array.isArray(pipeline)) {
     return;
   }
@@ -17,9 +17,21 @@ module.exports = function stringifyAccumulatorOptions(pipeline) {
       }
     }
 
+    const stageType = Object.keys(stage)[0];
+    if (stageType && typeof stage[stageType] === 'object') {
+      const stageOptions = stage[stageType];
+      for (const key of Object.keys(stageOptions)) {
+        if (stageOptions[key] != null &&
+            stageOptions[key].$function != null &&
+            typeof stageOptions[key].$function.body === 'function') {
+          stageOptions[key].$function.body = stageOptions[key].$function.body.toString();
+        }
+      }
+    }
+
     if (stage.$facet != null) {
       for (const key of Object.keys(stage.$facet)) {
-        stringifyAccumulatorOptions(stage.$facet[key]);
+        stringifyFunctionOperators(stage.$facet[key]);
       }
     }
   }
diff --git a/test/helpers/aggregate.test.js b/test/helpers/aggregate.test.js
index c3683cea959..54f5702d553 100644
--- a/test/helpers/aggregate.test.js
+++ b/test/helpers/aggregate.test.js
@@ -1,9 +1,9 @@
 'use strict';
 
 const assert = require('assert');
-const stringifyAccumulatorOptions = require('../../lib/helpers/aggregate/stringifyAccumulatorOptions');
+const stringifyFunctionOperators = require('../../lib/helpers/aggregate/stringifyFunctionOperators');
 
-describe('stringifyAccumulatorOptions', function() {
+describe('stringifyFunctionOperators', function() {
   it('converts accumulator args to strings (gh-9364)', function() {
     const pipeline = [{
       $group: {
@@ -35,11 +35,31 @@ describe('stringifyAccumulatorOptions', function() {
       }
     }];
 
-    stringifyAccumulatorOptions(pipeline);
+    stringifyFunctionOperators(pipeline);
 
     assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.init, 'string');
     assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.accumulate, 'string');
     assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.merge, 'string');
     assert.equal(typeof pipeline[0].$group.avgCopies.$accumulator.finalize, 'string');
   });
+
+  it('converts function args to strings (gh-9897)', function() {
+    const pipeline = [{
+      $addFields: {
+        newField: {
+          $function: {
+            body: function() {
+              return true;
+            },
+            args: ['$oldField'],
+            lang: 'js'
+          }
+        }
+      }
+    }];
+
+    stringifyFunctionOperators(pipeline);
+
+    assert.equal(typeof pipeline[0].$addFields.newField.$function.body, 'string');
+  });
 });
\ No newline at end of file

From ca8fe60c7aaab93119bbf6bd0152ab5ee3943004 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?D=C3=A1vid=20Nam=C3=A9nyi?= <dnamenyi@gmail.com>
Date: Wed, 10 Feb 2021 13:36:42 +0100
Subject: [PATCH 1691/2348] =?UTF-8?q?=F0=9F=93=9D=20fixed=20confusing=20se?=
 =?UTF-8?q?ntence=20in=20Schema=20docs?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 docs/guide.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide.pug b/docs/guide.pug
index 1695fb55869..7f26bddef99 100644
--- a/docs/guide.pug
+++ b/docs/guide.pug
@@ -378,7 +378,7 @@ block content
     const personSchema = new Schema({
       n: {
         type: String,
-        // Now accessing `name` will get you the value of `n`, and setting `n` will set the value of `name`
+        // Now accessing `name` will get you the value of `n`, and setting `name` will set the value of `n`
         alias: 'name'
       }
     });

From 7c41ddcd4a54eb49f04993a1882cf1b888c37bf3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 12:12:11 -0500
Subject: [PATCH 1692/2348] fix: avoid copying Object.prototype properties when
 cloning

Fix #9876
---
 lib/helpers/clone.js                   |  2 +-
 lib/helpers/query/castFilterPath.js    |  2 +-
 lib/helpers/update/castArrayFilters.js |  3 +--
 lib/query.js                           |  2 +-
 lib/schema.js                          | 10 +++++-----
 lib/utils.js                           |  2 +-
 package.json                           |  2 +-
 7 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/lib/helpers/clone.js b/lib/helpers/clone.js
index 5f0b2c92960..1056b02e2a1 100644
--- a/lib/helpers/clone.js
+++ b/lib/helpers/clone.js
@@ -111,7 +111,7 @@ function cloneObject(obj, options, isArrayChild) {
   const ret = {};
   let hasKeys;
 
-  for (const k in obj) {
+  for (const k of Object.keys(obj)) {
     if (specialProperties.has(k)) {
       continue;
     }
diff --git a/lib/helpers/query/castFilterPath.js b/lib/helpers/query/castFilterPath.js
index 74ff1c2aaf2..42b8460ceda 100644
--- a/lib/helpers/query/castFilterPath.js
+++ b/lib/helpers/query/castFilterPath.js
@@ -25,7 +25,7 @@ module.exports = function castFilterPath(query, schematype, val) {
       if (nested && schematype && !schematype.caster) {
         const _keys = Object.keys(nested);
         if (_keys.length && isOperator(_keys[0])) {
-          for (const key in nested) {
+          for (const key of Object.keys(nested)) {
             nested[key] = schematype.castForQueryWrapper({
               $conditional: key,
               val: nested[key],
diff --git a/lib/helpers/update/castArrayFilters.js b/lib/helpers/update/castArrayFilters.js
index 57018d9fb10..fef89346393 100644
--- a/lib/helpers/update/castArrayFilters.js
+++ b/lib/helpers/update/castArrayFilters.js
@@ -38,8 +38,7 @@ module.exports = function castArrayFilters(query) {
     if (filter == null) {
       throw new Error(`Got null array filter in ${arrayFilters}`);
     }
-    for (const key in filter) {
-
+    for (const key of Object.keys(filter)) {
       if (filter[key] == null) {
         continue;
       }
diff --git a/lib/query.js b/lib/query.js
index 21e19d205ed..3e1943e3cc0 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4966,7 +4966,7 @@ Query.prototype.tailable = function(val, opts) {
   }
 
   if (opts && typeof opts === 'object') {
-    for (const key in opts) {
+    for (const key of Object.keys(opts)) {
       if (key === 'awaitdata') {
         // For backwards compatibility
         this.options[key] = !!opts[key];
diff --git a/lib/schema.js b/lib/schema.js
index af350ffbaa9..7502b3ba1a7 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -694,18 +694,18 @@ Schema.prototype.path = function(path, obj) {
   }
 
   if (schemaType.$isSingleNested) {
-    for (const key in schemaType.schema.paths) {
+    for (const key of Object.keys(schemaType.schema.paths)) {
       this.singleNestedPaths[path + '.' + key] = schemaType.schema.paths[key];
     }
-    for (const key in schemaType.schema.singleNestedPaths) {
+    for (const key of Object.keys(schemaType.schema.singleNestedPaths)) {
       this.singleNestedPaths[path + '.' + key] =
         schemaType.schema.singleNestedPaths[key];
     }
-    for (const key in schemaType.schema.subpaths) {
+    for (const key of Object.keys(schemaType.schema.subpaths)) {
       this.singleNestedPaths[path + '.' + key] =
         schemaType.schema.subpaths[key];
     }
-    for (const key in schemaType.schema.nested) {
+    for (const key of Object.keys(schemaType.schema.nested)) {
       this.singleNestedPaths[path + '.' + key] = 'nested';
     }
 
@@ -1156,7 +1156,7 @@ Schema.prototype.hasMixedParent = function(path) {
   path = '';
   for (let i = 0; i < subpaths.length; ++i) {
     path = i > 0 ? path + '.' + subpaths[i] : subpaths[i];
-    if (path in this.paths &&
+    if (this.paths.hasOwnProperty(path) &&
         this.paths[path] instanceof MongooseTypes.Mixed) {
       return this.paths[path];
     }
diff --git a/lib/utils.js b/lib/utils.js
index c19fcabfa9f..ce69c9f87a5 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -332,7 +332,7 @@ exports.toObject = function toObject(obj) {
   if (exports.isPOJO(obj)) {
     ret = {};
 
-    for (const k in obj) {
+    for (const k of Object.keys(obj)) {
       if (specialProperties.has(k)) {
         continue;
       }
diff --git a/package.json b/package.json
index 2c62532081a..6a20d5d335b 100644
--- a/package.json
+++ b/package.json
@@ -25,7 +25,7 @@
     "mongodb": "3.6.4",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
-    "mquery": "3.2.3",
+    "mquery": "3.2.4",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.2.1",

From 1e9eda3b2439594181673666b89487605087be84 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 13:02:56 -0500
Subject: [PATCH 1693/2348] test(document): repro #9889

---
 test/document.test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index dec8f31dc2f..7828d8bf685 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -5853,6 +5853,26 @@ describe('document', function() {
       assert.equal(doc.totalValue, 5);
     });
 
+    it('calls array getters (gh-9889)', function() {
+      let called = 0;
+      const testSchema = new mongoose.Schema({
+        arr: [{
+          type: 'ObjectId',
+          ref: 'Doesnt Matter',
+          get: () => {
+            ++called;
+            return 42;
+          }
+        }]
+      });
+
+      const Test = db.model('Test', testSchema);
+
+      const doc = new Test({ arr: [new mongoose.Types.ObjectId()] });
+      assert.deepEqual(doc.toObject({ getters: true }).arr, [42]);
+      assert.equal(called, 1);
+    });
+
     it('nested virtuals + nested toJSON (gh-6294)', function() {
       const schema = mongoose.Schema({
         nested: {

From b3013744121cab4ef1c4e25a48887dacb4224107 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 13:03:09 -0500
Subject: [PATCH 1694/2348] fix(document): apply getters on array elements when
 calling `toObject({ getters: true })`

Re: #9889
---
 lib/schema/array.js         | 11 +++++++++--
 lib/schema/documentarray.js |  8 ++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 8a304189623..1abcdfc4252 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -261,12 +261,19 @@ SchemaArray.prototype.enum = function() {
  */
 
 SchemaArray.prototype.applyGetters = function(value, scope) {
-  if (this.caster.options && this.caster.options.ref) {
+  if (scope != null && scope.populated(this.path)) {
     // means the object id was populated
     return value;
   }
 
-  return SchemaType.prototype.applyGetters.call(this, value, scope);
+  const ret = SchemaType.prototype.applyGetters.call(this, value, scope);
+  if (Array.isArray(ret)) {
+    const len = ret.length;
+    for (let i = 0; i < len; ++i) {
+      ret[i] = this.caster.applyGetters(ret[i], scope);
+    }
+  }
+  return ret;
 };
 
 SchemaArray.prototype._applySetters = function(value, scope, init, priorVal) {
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index ac88560286e..1d50941f239 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -479,6 +479,14 @@ DocumentArrayPath.prototype.clone = function() {
   return schematype;
 };
 
+/*!
+ * ignore
+ */
+
+DocumentArrayPath.prototype.applyGetters = function(value, scope) {
+  return SchemaType.prototype.applyGetters.call(this, value, scope);
+};
+
 /*!
  * Scopes paths selected in a query to this array.
  * Necessary for proper default application of subdocument values.

From 7b9ccb051b3d77a014360c2f374a3c6dbc242247 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 13:15:54 -0500
Subject: [PATCH 1695/2348] style: fix lint

---
 test/document.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 7828d8bf685..104f50220a9 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9989,8 +9989,8 @@ describe('document', function() {
       });
       assert.equal(count, 1);
     });
-  });  
-    
+  });
+
   it('gh9880', function(done) {
     const testSchema = new Schema({
       prop: String,

From 03f7e5d5bae2a610e5fa9350626c6022092c0ac9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 13:22:22 -0500
Subject: [PATCH 1696/2348] test(document): repro #9889

---
 test/document.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 104f50220a9..4bc194033ea 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -5873,6 +5873,30 @@ describe('document', function() {
       assert.equal(called, 1);
     });
 
+    it('doesnt call setters when init-ing an array (gh-9889)', function() {
+      let called = 0;
+      const testSchema = new mongoose.Schema({
+        arr: [{
+          type: 'ObjectId',
+          set: v => {
+            ++called;
+            return v;
+          }
+        }]
+      });
+
+      const Test = db.model('Test', testSchema);
+
+      return co(function*() {
+        let doc = yield Test.create({ arr: [new mongoose.Types.ObjectId()] });
+        assert.equal(called, 1);
+
+        called = 0;
+        doc = yield Test.findById(doc);
+        assert.equal(called, 0);
+      });
+    });
+
     it('nested virtuals + nested toJSON (gh-6294)', function() {
       const schema = mongoose.Schema({
         nested: {

From 0c19536f9bc57a14000dca0d8ef3d6709c57e5f7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 13:42:14 -0500
Subject: [PATCH 1697/2348] fix(document): skip applying array element setters
 when init-ing an array

Fix #9889
---
 lib/schematype.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/schematype.js b/lib/schematype.js
index fc5fba69c7a..973efe9478f 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1049,8 +1049,11 @@ SchemaType.prototype.getDefault = function(scope, init) {
  * @api private
  */
 
-SchemaType.prototype._applySetters = function(value, scope) {
+SchemaType.prototype._applySetters = function(value, scope, init) {
   let v = value;
+  if (init) {
+    return v;
+  }
   const setters = this.setters;
 
   for (const setter of utils.clone(setters).reverse()) {

From 937bf8f604f9fbf8dcab29d928f20fc76c4e468f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 13:55:47 -0500
Subject: [PATCH 1698/2348] style: fix lint

---
 test/document.test.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/test/document.test.js b/test/document.test.js
index 4bc194033ea..277510be6c9 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -5892,7 +5892,8 @@ describe('document', function() {
         assert.equal(called, 1);
 
         called = 0;
-        doc = yield Test.findById(doc);
+        doc = yield Test.findById(doc._id);
+        assert.ok(doc);
         assert.equal(called, 0);
       });
     });

From 6fe95f01f8a4f6e389d7a6546e91b1fc52450428 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 12 Feb 2021 16:44:57 -0500
Subject: [PATCH 1699/2348] chore: release 5.11.16

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 91130da0e10..658db73aa3e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.11.16 / 2021-02-12
+====================
+ * fix(document): skip applying array element setters when init-ing an array #9889
+ * fix: upgrade to mongodb driver 3.6.4 #9893 [jooeycheng](https://github.com/jooeycheng)
+ * fix: avoid copying Object.prototype properties when cloning #9876
+ * fix(aggregate): automatically convert functions to strings when using `$function` operator #9897
+ * fix: call pre-remove hooks for subdocuments #9895 #9885 [IslandRhythms](https://github.com/IslandRhythms)
+ * docs: fix confusing sentence in Schema docs #9914 [namenyi](https://github.com/namenyi)
+
 5.11.15 / 2021-02-03
 ====================
  * fix(document): fix issues with `isSelected` as an path in a nested schema #9884 #9873 [IslandRhythms](https://github.com/IslandRhythms)
diff --git a/package.json b/package.json
index 6a20d5d335b..b63bd9a5b7e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.15",
+  "version": "5.11.16",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 007fb69caf0a5863aee497a064745368d0c539f6 Mon Sep 17 00:00:00 2001
From: khaledosama999 <khaledosama52@gmail.com>
Date: Sat, 13 Feb 2021 00:34:52 +0200
Subject: [PATCH 1700/2348] feat: add batch processing for eachAsync

---
 docs/api/querycursor.html             |  5 +-
 index.d.ts                            | 14 ++---
 lib/helpers/cursor/eachAsync.js       | 29 +++++++++--
 test/helpers/cursor.eachAsync.test.js | 75 +++++++++++++++++++++++++++
 4 files changed, 113 insertions(+), 10 deletions(-)

diff --git a/docs/api/querycursor.html b/docs/api/querycursor.html
index 31aeb4dda1d..98f3e5ad8fe 100644
--- a/docs/api/querycursor.html
+++ b/docs/api/querycursor.html
@@ -20,7 +20,10 @@
 <span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Marks this cursor as closed. Will stop streaming and subsequent calls to <code>next()</code> will error.</p>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-eachAsync"><a href="#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
 <span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[options]
 <span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.parallel]
-<span class="method-type">&laquo;Number&raquo;</span> the number of promises to execute in parallel. Defaults to 1.</li></ul><li class="param">[callback]
+<span class="method-type">&laquo;Number&raquo;</span> the number of promises to execute in parallel. Defaults to 1.
+<span class="method-type">&laquo;Object&raquo;</span><ul style="margin-top: 0.5em"><li>[options.batchSize]
+  <span class="method-type">&laquo;Number&raquo;</span> The size of documents processed by the passed in function to eachAsync (works with the parallel option)</li></ul>
+</li></ul><li class="param">[callback]
 <span class="method-type">&laquo;Function&raquo;</span> executed when all docs have been processed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute <code>fn</code> for every document in the cursor. If <code>fn</code> returns a promise, will wait for the promise to resolve before iterating on to the next one. Returns a promise that resolves when done.</p>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-map"><a href="#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
 <span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;QueryCursor&raquo;</span> </li></ul><div><p>Registers a transform function which subsequently maps documents retrieved via the streams interface or <code>.next()</code></p>
 
diff --git a/index.d.ts b/index.d.ts
index 3b72826c90c..6150b4bf156 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2231,12 +2231,13 @@ declare module 'mongoose' {
     close(callback: (err: CallbackError) => void): void;
 
     /**
-     * Execute `fn` for every document in the cursor. If `fn` returns a promise,
+     * Execute `fn` for every document(s) in the cursor. If batchSize is provided
+     * `fn` will be executed for each batch of documents. If `fn` returns a promise,
      * will wait for the promise to resolve before iterating on to the next one.
      * Returns a promise that resolves when done.
      */
-    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }): Promise<void>;
-    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }, cb?: (err: CallbackError) => void): void;
+    eachAsync(fn: (doc: DocType| [DocType]) => any, options?: { parallel?: number, batchSize?: number }): Promise<void>;
+    eachAsync(fn: (doc: DocType| [DocType]) => any, options?: { parallel?: number, batchSize?: number }, cb?: (err: CallbackError) => void): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
@@ -2396,12 +2397,13 @@ declare module 'mongoose' {
     close(callback: (err: CallbackError) => void): void;
 
     /**
-     * Execute `fn` for every document in the cursor. If `fn` returns a promise,
+     * Execute `fn` for every document(s) in the cursor. If batchSize is provided
+     * `fn` will be executed for each batch of documents. If `fn` returns a promise,
      * will wait for the promise to resolve before iterating on to the next one.
      * Returns a promise that resolves when done.
      */
-    eachAsync(fn: (doc: any) => any, options?: { parallel?: number }): Promise<void>;
-    eachAsync(fn: (doc: any) => any, options?: { parallel?: number }, cb?: (err: CallbackError) => void): void;
+    eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }): Promise<void>;
+    eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }, cb?: (err: CallbackError) => void): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 4afff032fe8..96e9c933a75 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -22,6 +22,7 @@ const promiseOrCallback = require('../promiseOrCallback');
 
 module.exports = function eachAsync(next, fn, options, callback) {
   const parallel = options.parallel || 1;
+  const batchSize = options.batchSize;
   const enqueue = asyncQueue();
 
   return promiseOrCallback(callback, cb => {
@@ -32,6 +33,7 @@ module.exports = function eachAsync(next, fn, options, callback) {
     let drained = false;
     let handleResultsInProgress = 0;
     let currentDocumentIndex = 0;
+    let documentsBatch = [];
 
     let error = null;
     for (let i = 0; i < parallel; ++i) {
@@ -57,6 +59,8 @@ module.exports = function eachAsync(next, fn, options, callback) {
           if (handleResultsInProgress <= 0) {
             finalCallback(null);
           }
+          else if (batchSize && documentsBatch.length)
+            handleNextResult(documentsBatch, currentDocumentIndex++, handleNextResultCallBack);
           return done();
         }
 
@@ -66,8 +70,25 @@ module.exports = function eachAsync(next, fn, options, callback) {
         // make sure we know that we still have a result to handle re: #8422
         process.nextTick(() => done());
 
-        handleNextResult(doc, currentDocumentIndex++, function(err) {
-          --handleResultsInProgress;
+        if (batchSize) {
+          documentsBatch.push(doc);
+        }
+
+        // If the current documents size is less than the provided patch size don't process the documents yet
+        if (batchSize && documentsBatch.length !== batchSize) {
+          setTimeout(() => enqueue(fetch), 0);
+          return;
+        }
+
+        const docsToProcess = batchSize ? documentsBatch : doc;
+
+        function handleNextResultCallBack(err) {
+          if (batchSize) {
+            handleResultsInProgress -= documentsBatch.length;
+            documentsBatch = [];
+          }
+          else
+            --handleResultsInProgress;
           if (err != null) {
             error = err;
             return finalCallback(err);
@@ -77,7 +98,9 @@ module.exports = function eachAsync(next, fn, options, callback) {
           }
 
           setTimeout(() => enqueue(fetch), 0);
-        });
+        }
+
+        handleNextResult(docsToProcess, currentDocumentIndex++, handleNextResultCallBack);
       });
     }
   }
diff --git a/test/helpers/cursor.eachAsync.test.js b/test/helpers/cursor.eachAsync.test.js
index b7d847b055a..5ea083ef3e5 100644
--- a/test/helpers/cursor.eachAsync.test.js
+++ b/test/helpers/cursor.eachAsync.test.js
@@ -59,4 +59,79 @@ describe('eachAsync()', function() {
       then(() => eachAsync(next, fn, { parallel: 2 })).
       then(() => assert.equal(numDone, max));
   });
+
+  it('it processes the documents in batches successfully', () => {
+    const batchSize = 3;
+    let numberOfDocuments = 0;
+    const maxNumberOfDocuments = 9;
+    let numberOfBatchesProcessed = 0;
+
+    function next(cb) {
+      setTimeout(() => {
+        if (++numberOfDocuments > maxNumberOfDocuments) {
+          cb(null, null);
+        }
+        return cb(null, { id: numberOfDocuments });
+      }, 0);
+    }
+
+    const fn = (docs, index) => {
+      assert.equal(docs.length, batchSize);
+      assert.equal(index, numberOfBatchesProcessed++);
+    };
+
+    return eachAsync(next, fn, { batchSize });
+  });
+
+  it('it processes the documents in batches even if the batch size % document count is not zero successfully', () => {
+    const batchSize = 3;
+    let numberOfDocuments = 0;
+    const maxNumberOfDocuments = 10;
+    let numberOfBatchesProcessed = 0;
+
+    function next(cb) {
+      setTimeout(() => {
+        if (++numberOfDocuments > maxNumberOfDocuments) {
+          cb(null, null);
+        }
+        return cb(null, { id: numberOfDocuments });
+      }, 0);
+    }
+
+    const fn = (docs, index) => {
+      assert.equal(index, numberOfBatchesProcessed++);
+      if (index == 3) {
+        assert.equal(docs.length, 1);
+      }
+      else {
+        assert.equal(docs.length, batchSize);
+      }
+    };
+
+    return eachAsync(next, fn, { batchSize });
+  });
+
+  it('it processes the documents in batches with the parallel option provided', () => {
+    const batchSize = 3;
+    const parallel = 3;
+    let numberOfDocuments = 0;
+    const maxNumberOfDocuments = 9;
+    let numberOfBatchesProcessed = 0;
+
+    function next(cb) {
+      setTimeout(() => {
+        if (++numberOfDocuments > maxNumberOfDocuments) {
+          cb(null, null);
+        }
+        return cb(null, { id: numberOfDocuments });
+      }, 0);
+    }
+
+    const fn = (docs, index) => {
+      assert.equal(index, numberOfBatchesProcessed++);
+      assert.equal(docs.length, batchSize);
+    };
+
+    return eachAsync(next, fn, { batchSize, parallel });
+  });
 });
\ No newline at end of file

From 003e4a85a3dd1e7addd02d88f4b809371901d58e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Feb 2021 10:06:14 -0500
Subject: [PATCH 1701/2348] test(schema): repro #9912

---
 test/model.indexes.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 107aabe52ed..74e10e97735 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -552,6 +552,31 @@ describe('model', function() {
         then(dropped => assert.equal(dropped.length, 0));
     });
 
+    it('uses schema-level collation by default (gh-9912)', function() {
+      return co(function*() {
+        yield db.db.collection('User').drop().catch(() => {});
+
+        let userSchema = new mongoose.Schema({ username: String }, {
+          collation: {
+            locale: 'en',
+            strength: 2
+          }
+        });
+        userSchema.index({ username: 1 }, { unique: true });
+        let User = db.model('User', userSchema, 'User');
+
+        yield User.init();
+        let indexes = yield User.listIndexes();
+        assert.equal(indexes.length, 2);
+        assert.deepEqual(indexes[1].key, { username: 1 });
+        console.log(indexes);
+        assert.ok(indexes[1].collation);
+        assert.equal(indexes[1].collation.strength, 2);
+
+        yield User.collection.drop();
+      });
+    });
+
     it('different collation with syncIndexes() (gh-8521)', function() {
       return co(function*() {
         yield db.db.collection('User').drop().catch(() => {});

From 6c78829689f8addc26ef0b2ba8fb321e5d86733d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Feb 2021 10:40:20 -0500
Subject: [PATCH 1702/2348] fix(model): use schema-level default collation for
 indexes if index doesn't have collation

Fix #9912
---
 lib/model.js               | 4 ++++
 test/model.indexes.test.js | 1 -
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 04cb57a31c4..99002b330b3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1650,6 +1650,10 @@ function _ensureIndexes(model, options, callback) {
     if ('background' in options) {
       indexOptions.background = options.background;
     }
+    if (model.schema.options.hasOwnProperty('collation') &&
+        !indexOptions.hasOwnProperty('collation')) {
+      indexOptions.collation = model.schema.options.collation;
+    }
 
     const methodName = useCreateIndex ? 'createIndex' : 'ensureIndex';
     model.collection[methodName](indexFields, indexOptions, utils.tick(function(err, name) {
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 74e10e97735..50ed7c86125 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -569,7 +569,6 @@ describe('model', function() {
         let indexes = yield User.listIndexes();
         assert.equal(indexes.length, 2);
         assert.deepEqual(indexes[1].key, { username: 1 });
-        console.log(indexes);
         assert.ok(indexes[1].collation);
         assert.equal(indexes[1].collation.strength, 2);
 

From aef25e09d54d272f14c93cbfa01d0986105e41ef Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 13 Feb 2021 10:51:43 -0500
Subject: [PATCH 1703/2348] test: fix flakey test and lint errors

---
 test/errors.validation.test.js | 4 ++--
 test/model.indexes.test.js     | 6 +++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 69a32d020e3..68c378840e1 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -243,14 +243,14 @@ describe('ValidationError', function() {
   });
 
   describe('when user code defines a r/o Error#toJSON', function() {
-    it('shoud not fail', function(done) {
+    it('should not fail', function(done) {
       const err = [];
       const child = require('child_process')
         .fork('./test/isolated/project-has-error.toJSON.js', ['--no-warnings'], { silent: true });
 
       child.stderr.on('data', function(buf) { err.push(buf); });
       child.on('exit', function(code) {
-        const stderr = err.join('');
+        const stderr = err.filter(line => !line.includes('Warning: ')).join('');
         assert.equal(stderr, '');
         assert.equal(code, 0);
         done();
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 50ed7c86125..d6d262bd91c 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -556,17 +556,17 @@ describe('model', function() {
       return co(function*() {
         yield db.db.collection('User').drop().catch(() => {});
 
-        let userSchema = new mongoose.Schema({ username: String }, {
+        const userSchema = new mongoose.Schema({ username: String }, {
           collation: {
             locale: 'en',
             strength: 2
           }
         });
         userSchema.index({ username: 1 }, { unique: true });
-        let User = db.model('User', userSchema, 'User');
+        const User = db.model('User', userSchema, 'User');
 
         yield User.init();
-        let indexes = yield User.listIndexes();
+        const indexes = yield User.listIndexes();
         assert.equal(indexes.length, 2);
         assert.deepEqual(indexes[1].key, { username: 1 });
         assert.ok(indexes[1].collation);

From 71c3ea9bf251d2fd3dbd464c3aecf52b46a3c55a Mon Sep 17 00:00:00 2001
From: ggurkal <giraygurkal@gmail.com>
Date: Sun, 14 Feb 2021 18:34:56 +0100
Subject: [PATCH 1704/2348] chore(typescript): re-order Schema generics for
 query helpers type

---
 index.d.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 42d2769fa65..75eee780f12 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,8 +99,8 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document, TQueryHelpers = {}>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
-  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
+  export function model<T extends Document, TQueryHelpers = Record<string, any>>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
+  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = Record<string, any>>(
     name: string,
     schema?: Schema<T, U, TQueryHelpers>,
     collection?: string,
@@ -613,7 +613,7 @@ declare module 'mongoose' {
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter {
+  interface Model<T extends Document, TQueryHelpers = Record<string, any>> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
@@ -1067,7 +1067,7 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, TQueryHelpers = {}, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined, TQueryHelpers = Record<string, any>> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1815,7 +1815,7 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false };
 
-  class Query<ResultType, DocType extends Document, THelpers = {}> {
+  class Query<ResultType, DocType extends Document, THelpers = Record<string, any>> {
     _mongooseOptions: MongooseQueryOptions;
 
     /** Executes the query */

From 4c6a63e3e5364ae0b0179e7059e8dbe9d894db08 Mon Sep 17 00:00:00 2001
From: ggurkal <giraygurkal@gmail.com>
Date: Sun, 14 Feb 2021 18:37:10 +0100
Subject: [PATCH 1705/2348] test(typescript): query helpers & cast "res" to any

---
 test/typescript/queries.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index a919b1195f4..bb3583b1e36 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,10 +1,10 @@
-import { Schema, model, Document, Types, Query } from 'mongoose';
+import { Schema, model, Document, Types, Query, Model } from 'mongoose';
 
 interface QueryHelpers {
   byName(name: string): Query<Array<ITest>, ITest, QueryHelpers>;
 }
 
-const schema: Schema<ITest, QueryHelpers> = new Schema({ name: { type: 'String' }, tags: [String] });
+const schema: Schema<ITest, Model<ITest>, undefined, QueryHelpers> = new Schema({ name: { type: 'String' }, tags: [String] });
 
 schema.query.byName = function(name: string): Query<Array<ITest>, ITest, QueryHelpers> {
   return this.find({ name });
@@ -51,8 +51,8 @@ Test.findOneAndUpdate({ name: 'test' }, { $set: { name: 'test2' } }).then((res:
 Test.findOneAndUpdate({ name: 'test' }, { $inc: { age: 2 } }).then((res: ITest | null) => console.log(res));
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, new: true }).then((res: ITest) => { res.name = 'test4'; });
 Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { upsert: true, returnOriginal: false }).then((res: ITest) => { res.name = 'test4'; });
-Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { rawResult: true }).then((res) => { console.log(res.ok); });
-Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { new: true, upsert: true, rawResult: true }).then((res) => { console.log(res.ok); });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { rawResult: true }).then((res: any) => { console.log(res.ok); });
+Test.findOneAndUpdate({ name: 'test' }, { name: 'test3' }, { new: true, upsert: true, rawResult: true }).then((res: any) => { console.log(res.ok); });
 
 Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'test2' }).exec().then((res: ITest | null) => console.log(res));
 

From 796f9d7565a1961edf6a773a262699043804f949 Mon Sep 17 00:00:00 2001
From: "John H. Kohler" <jhunterkohler@gmail.com>
Date: Mon, 15 Feb 2021 10:52:05 -0500
Subject: [PATCH 1706/2348] add object id.toString() on methods

---
 lib/types/map.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/lib/types/map.js b/lib/types/map.js
index b992259870b..f22daca760d 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const Mixed = require('../schema/mixed');
+const ObjectId = require('./objectid')
 const deepEqual = require('../utils').deepEqual;
 const get = require('../helpers/get');
 const handleSpreadDoc = require('../helpers/document/handleSpreadDoc');
@@ -41,6 +42,10 @@ class MongooseMap extends Map {
   }
 
   get(key, options) {
+    if(key instanceof ObjectId) {
+      key = key.toString();
+    }
+
     options = options || {};
     if (options.getters === false) {
       return super.get(key);
@@ -49,6 +54,10 @@ class MongooseMap extends Map {
   }
 
   set(key, value) {
+    if(key instanceof ObjectId) {
+        key = key.toString();
+    }
+
     checkValidKey(key);
     value = handleSpreadDoc(value);
 
@@ -107,6 +116,10 @@ class MongooseMap extends Map {
   }
 
   delete(key) {
+    if(key instanceof ObjectId) {
+      key = key.toString();
+    }
+
     this.set(key, undefined);
     super.delete(key);
   }

From 8d0311eef495c60385e9f2fc17a81eb8b996e4f8 Mon Sep 17 00:00:00 2001
From: "John H. Kohler" <jhunterkohler@gmail.com>
Date: Mon, 15 Feb 2021 11:17:44 -0500
Subject: [PATCH 1707/2348] fix linting errors

---
 lib/types/map.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/types/map.js b/lib/types/map.js
index f22daca760d..8d67324ea29 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -1,7 +1,7 @@
 'use strict';
 
 const Mixed = require('../schema/mixed');
-const ObjectId = require('./objectid')
+const ObjectId = require('./objectid');
 const deepEqual = require('../utils').deepEqual;
 const get = require('../helpers/get');
 const handleSpreadDoc = require('../helpers/document/handleSpreadDoc');
@@ -42,7 +42,7 @@ class MongooseMap extends Map {
   }
 
   get(key, options) {
-    if(key instanceof ObjectId) {
+    if (key instanceof ObjectId) {
       key = key.toString();
     }
 
@@ -54,8 +54,8 @@ class MongooseMap extends Map {
   }
 
   set(key, value) {
-    if(key instanceof ObjectId) {
-        key = key.toString();
+    if (key instanceof ObjectId) {
+      key = key.toString();
     }
 
     checkValidKey(key);
@@ -116,7 +116,7 @@ class MongooseMap extends Map {
   }
 
   delete(key) {
-    if(key instanceof ObjectId) {
+    if (key instanceof ObjectId) {
       key = key.toString();
     }
 

From f73a35bf9c92139880b35b68aa426ee23ea43457 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 10:03:22 -0500
Subject: [PATCH 1708/2348] fix(index.d.ts): support `{ type: String }` in
 schema definition when using SchemaDefinitionType generic

Fix #9911
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index e349d0cd652..d57c64706b9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1365,7 +1365,7 @@ declare module 'mongoose' {
   }
 
   interface SchemaTypeOptions<T> {
-    type: T;
+    type: T | SchemaDefinitionWithBuiltInClass<T>;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;

From 17e9773dbd37b2eb6be6f8d8b8451def6328ac86 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 11:27:34 -0500
Subject: [PATCH 1709/2348] test(populate): repro #9906

---
 test/model.populate.test.js | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 97871f1ac92..779d801c713 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9869,6 +9869,7 @@ describe('model: populate:', function() {
       assert.deepEqual(findCallOptions[0].virtuals, ['foo']);
     });
   });
+
   it('gh-9833', function() {
     const Books = db.model('books', new Schema({ name: String, tags: [{ type: Schema.Types.ObjectId, ref: 'tags' }] }));
     const Tags = db.model('tags', new Schema({ author: Schema.Types.ObjectId }));
@@ -9907,4 +9908,37 @@ describe('model: populate:', function() {
       assert.ok(!Array.isArray(populatedBooks[0].tags[0].author));
     });
   });
+
+  it('handles perDocumentLimit where multiple documents reference the same populated doc (gh-9906)', function() {
+    const postSchema = new Schema({
+      title: String,
+      commentsIds: [{ type: Schema.ObjectId, ref: 'Comment' }]
+    });
+    const Post = db.model('Post', postSchema);
+
+    const commentSchema = new Schema({ content: String });
+    const Comment = db.model('Comment', commentSchema);
+
+    return co(function*() {
+      const commonComment = new Comment({ content: 'Im used in two posts' });
+      yield commonComment.save();
+
+      const comments = yield Comment.create([
+        { content: 'Nice first post' },
+        { content: 'Nice second post' }
+      ]);
+
+      let posts = yield Post.create([
+        { title: 'First post', commentsIds: [commonComment, comments[0]] },
+        { title: 'Second post', commentsIds: [commonComment, comments[1]] }
+      ]);
+
+      posts = yield Post.find().populate({ path: 'commentsIds', perDocumentLimit: 2, sort: { content: 1 } });
+      assert.equal(posts.length, 2);
+      assert.ok(!Array.isArray(posts[0].commentsIds[0]));
+
+      assert.deepEqual(posts[0].toObject().commentsIds.map(c => c.content), ['Im used in two posts', 'Nice first post']);
+      assert.deepEqual(posts[1].toObject().commentsIds.map(c => c.content), ['Im used in two posts', 'Nice second post']);
+    });
+  });
 });

From 0757423a2ee15f4c6dad6adeb72c4bc35515c9a6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 11:27:46 -0500
Subject: [PATCH 1710/2348] fix(populate): handle `perDocumentLimit` when
 multiple documents reference the same populated doc

Fix #9906
---
 lib/model.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 99002b330b3..82fd28c27cf 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4592,7 +4592,12 @@ function _assign(model, vals, mod, assignmentOpts) {
           if (Array.isArray(rawDocs[key])) {
             rawDocs[key].push(val);
             rawOrder[key].push(i);
-          } else {
+          } else if (isVirtual ||
+            rawDocs[key].constructor !== val.constructor ||
+            String(rawDocs[key]._id) !== String(val._id)) {
+            // May need to store multiple docs with the same id if there's multiple models
+            // if we have discriminators or a ref function. But avoid converting to an array
+            // if we have multiple queries on the same model because of `perDocumentLimit` re: gh-9906
             rawDocs[key] = [rawDocs[key], val];
             rawOrder[key] = [rawOrder[key], i];
           }

From 18e5db1961ddcdd0f46081185c20f937b9c7337d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 11:49:31 -0500
Subject: [PATCH 1711/2348] docs(connection): clarify that
 `Connection#transaction()` promise resolves to a command result

Fix #9919
---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 185948e696b..83ff8f8c9a0 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -469,7 +469,7 @@ Connection.prototype.startSession = _wrapConnHelper(function startSession(option
  * @method transaction
  * @param {Function} fn Function to execute in a transaction
  * @param {mongodb.TransactionOptions} [options] Optional settings for the transaction
- * @return {Promise<Any>} promise that resolves to the returned value of `fn`
+ * @return {Promise<Any>} promise that is fulfilled if Mongoose successfully committed the transaction, or rejects if the transaction was aborted or if Mongoose failed to commit the transaction. If fulfilled, the promise resolves to a MongoDB command result.
  * @api public
  */
 

From 881ee620ac43afdedd789f6493e71915666a6aaf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 12:24:19 -0500
Subject: [PATCH 1712/2348] test(populate): repro #9913

---
 test/model.populate.test.js | 40 +++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 779d801c713..07639c5b104 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9909,6 +9909,46 @@ describe('model: populate:', function() {
     });
   });
 
+  it('sets not-found values to null for paths that are not in the schema (gh-9913)', function() {
+    const Books = db.model('books', new Schema({ name: String, tags: [{ type: 'ObjectId', ref: 'tags' }] }));
+    const Tags = db.model('tags', new Schema({ authors: [{ author: 'ObjectId' }] }));
+    const Authors = db.model('authors', new Schema({ name: String }));
+
+    return co(function*() {
+      const anAuthor = new Authors({ name: 'Author1' });
+      yield anAuthor.save();
+
+      const aTag = new Tags({ authors: [{ author: anAuthor.id }, { author: new mongoose.Types.ObjectId() }] });
+      yield aTag.save();
+
+      const aBook = new Books({ name: 'Book1', tags: [aTag.id] });
+      yield aBook.save();
+
+      const aggregateOptions = [
+        { $match: {
+          name: { $in: [aBook.name] }
+        } },
+        { $lookup: {
+          from: 'tags',
+          localField: 'tags',
+          foreignField: '_id',
+          as: 'tags'
+        } }
+      ];
+      const books = yield Books.aggregate(aggregateOptions).exec();
+
+      const populateOptions = [{
+        path: 'tags.authors.author',
+        model: 'authors',
+        select: '_id name'
+      }];
+
+      const populatedBooks = yield Books.populate(books, populateOptions);
+      assert.strictEqual(populatedBooks[0].tags[0].authors[0].author.name, 'Author1');
+      assert.strictEqual(populatedBooks[0].tags[0].authors[1].author, null);
+    });
+  });
+
   it('handles perDocumentLimit where multiple documents reference the same populated doc (gh-9906)', function() {
     const postSchema = new Schema({
       title: String,

From aa7b529be017ec5c7f158d6bf0ed1b8e736d1343 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 12:24:29 -0500
Subject: [PATCH 1713/2348] fix(populate): set not found values to `null` for
 paths that are not in the schema

Fix #9913
---
 lib/helpers/populate/assignVals.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 9fd51d80967..a09b1007473 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -240,7 +240,7 @@ function valueFilter(val, assignmentOpts, populateOptions) {
   if (populateOptions.justOne === false) {
     return [];
   }
-  return val;
+  return val == null ? val : null;
 }
 
 /*!

From de8fbf36ce766a261461a9708ddca8bff6b21a68 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 14:12:52 -0500
Subject: [PATCH 1714/2348] test(document): repro #9909

---
 test/document.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 277510be6c9..27b9b83c16f 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10057,4 +10057,30 @@ describe('document', function() {
       });
     });
   });
+
+  it('handles directly setting embedded document array element with projection (gh-9909)', function() {
+    const schema = Schema({
+      elements: [{
+        text: String,
+        subelements: [{
+          text: String
+        }]
+      }]
+    });
+
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      let doc = yield Test.create({ elements: [{ text: 'hello' }] });
+      doc = yield Test.findById(doc).select('elements');
+
+      doc.elements[0].subelements[0] = { text: 'my text' };
+      yield doc.save();
+
+      const fromDb = yield Test.findById(doc).lean();
+      assert.equal(fromDb.elements.length, 1);
+      assert.equal(fromDb.elements[0].subelements.length, 1);
+      assert.equal(fromDb.elements[0].subelements[0].text, 'my text');
+    });
+  });
 });

From b4bb52d1e7215dc12b08ab5e3b482235119461e3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 14:20:40 -0500
Subject: [PATCH 1715/2348] fix(document): handle directly setting embedded
 document array element with projection

Fix #9909
---
 lib/types/core_array.js    | 10 ++--------
 lib/types/documentarray.js | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index df66617d451..eb71de05e67 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -284,7 +284,7 @@ class CoreMongooseArray extends Array {
    * @memberOf MongooseArray
    */
 
-  _markModified(elem, embeddedPath) {
+  _markModified(elem) {
     const parent = this[arrayParentSymbol];
     let dirtyPath;
 
@@ -292,13 +292,7 @@ class CoreMongooseArray extends Array {
       dirtyPath = this[arrayPathSymbol];
 
       if (arguments.length) {
-        if (embeddedPath != null) {
-          // an embedded doc bubbled up the change
-          dirtyPath = dirtyPath + '.' + this.indexOf(elem) + '.' + embeddedPath;
-        } else {
-          // directly set an index
-          dirtyPath = dirtyPath + '.' + elem;
-        }
+        dirtyPath = dirtyPath + '.' + elem;
       }
 
       if (dirtyPath != null && dirtyPath.endsWith('.$')) {
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index 67afcbcfd3c..be533b9f549 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -330,6 +330,34 @@ class CoreDocumentArray extends CoreMongooseArray {
       }
     };
   }
+
+  _markModified(elem, embeddedPath) {
+    const parent = this[arrayParentSymbol];
+    let dirtyPath;
+
+    if (parent) {
+      dirtyPath = this[arrayPathSymbol];
+
+      if (arguments.length) {
+        if (embeddedPath != null) {
+          // an embedded doc bubbled up the change
+          const index = elem.__index;
+          dirtyPath = dirtyPath + '.' + index + '.' + embeddedPath;
+        } else {
+          // directly set an index
+          dirtyPath = dirtyPath + '.' + elem;
+        }
+      }
+
+      if (dirtyPath != null && dirtyPath.endsWith('.$')) {
+        return this;
+      }
+
+      parent.markModified(dirtyPath, arguments.length > 0 ? elem : parent);
+    }
+
+    return this;
+  }
 }
 
 if (util.inspect.custom) {

From a485c402541b14e7f8a00b50d4093e546be43db4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 17:14:59 -0500
Subject: [PATCH 1716/2348] fix(index.d.ts): make `SchemaTypeOptions#type`
 optional again to allow alternative typeKeys

Fix #9927
---
 index.d.ts                   | 2 +-
 test/typescript/main.test.js | 2 +-
 test/typescript/schema.ts    | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index d57c64706b9..4d4a6ee49a4 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1365,7 +1365,7 @@ declare module 'mongoose' {
   }
 
   interface SchemaTypeOptions<T> {
-    type: T | SchemaDefinitionWithBuiltInClass<T>;
+    type?: T | SchemaDefinitionWithBuiltInClass<T>;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 2d6b1188074..7dd5e51bef9 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -180,7 +180,7 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 1);
     const messageText = errors[0].messageText.messageText;
-    assert.ok(/Type 'StringConstructor' is not assignable to type.*number/.test(messageText), messageText);
+    assert.ok(/Type '.*StringConstructor.*' is not assignable to type.*number/.test(messageText), messageText);
   });
 
   it('document', function() {
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 4aed0505b31..43528dc4611 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -71,7 +71,7 @@ async function gh9857() {
   type UserModel = Model<UserDocument>;
 
   const schemaDefinition: UserSchemaDefinition = {
-    name: String,
+    name: { type: String },
     active: Boolean,
     points: Number
   };

From 527681c4d03c7b86f01f6a1e0a6313c40389f213 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 16 Feb 2021 19:30:32 -0500
Subject: [PATCH 1717/2348] docs(populate+schematypes): document the `$*`
 syntax for populating every entry in a map

Fix #9907
---
 docs/populate.pug    | 71 ++++++++++++++++++++++++++++++++++++++++++++
 docs/schematypes.pug | 26 ++++++++++++++++
 2 files changed, 97 insertions(+)

diff --git a/docs/populate.pug b/docs/populate.pug
index 27b9ec48af8..a9cee2d1031 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -74,6 +74,7 @@ block content
       <li><a href="#dynamic-ref">Dynamic References via `refPath`</a></li>
       <li><a href="#populate-virtuals">Populate Virtuals</a></li>
       <li><a href="#count">Populate Virtuals: The Count Option</a></li>
+      <li><a href="#populating-maps">Populating Maps</a></li>
       <li><a href="#populate-middleware">Populate in Middleware</a></li>
     </ul>
 
@@ -728,6 +729,76 @@ block content
     doc.numMembers; // 2
     ```
 
+    <h3 id="populating-maps"><a href="#populating-maps">Populating Maps</a></h3>
+
+    [Maps](/docs/schematypes.html#maps) are a type that represents an object with arbitrary
+    string keys. For example, in the below schema, `members` is a map from strings to ObjectIds.
+
+    ```javascript
+    const BandSchema = new Schema({
+      name: String,
+      members: {
+        type: Map,
+        of: {
+          type: 'ObjectId',
+          ref: 'Person'
+        }
+      }
+    });
+    const Band = mongoose.model('Band', bandSchema);
+    ```
+
+    This map has a `ref`, which means you can use `populate()` to populate all the ObjectIds
+    in the map. Suppose you have the below `band` document:
+
+    ```
+    const person1 = new Person({ name: 'Vince Neil' });
+    const person2 = new Person({ name: 'Mick Mars' });
+
+    const band = new Band({
+      name: 'Motley Crue',
+      members: {
+        'singer': person1._id,
+        'guitarist': person2._id
+      }
+    });
+    ```
+
+    You can `populate()` every element in the map by populating the special path `members.$*`.
+    `$*` is a special syntax that tells Mongoose to look at every key in the map.
+
+    ```javascript
+    const band = await Band.findOne({ name: 'Motley Crue' }).populate('members.$*');
+
+    band.members.get('singer'); // { _id: ..., name: 'Vince Neil' }
+    ```
+
+    You can also populate paths in maps of subdocuments using `$*`. For example, suppose you
+    have the below `librarySchema`:
+
+    ```javascript
+    const librarySchema = new Schema({
+      name: String,
+      books: {
+        type: Map,
+        of: new Schema({
+          title: String,
+          author: {
+            type: 'ObjectId',
+            ref: 'Person'
+          }
+        })
+      }
+    });
+    const Library = mongoose.model('Library, librarySchema');
+    ```
+
+    You can `populate()` every book's author by populating `books.$*.author`:
+
+    ```javascript
+    const libraries = await Library.find().populate('books.$*.author');
+    ```
+
     <h3 id="populate-middleware"><a href="#populate-middleware">Populate in Middleware</a></h3>
 
     You can populate in either pre or post [hooks](http://mongoosejs.com/docs/middleware.html). If you want to
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
index 7d08ee24737..7734c958929 100644
--- a/docs/schematypes.pug
+++ b/docs/schematypes.pug
@@ -608,6 +608,32 @@ block content
     Keys in a BSON object are ordered, so this means the [insertion order](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#Description)
     property of maps is maintained.
 
+    Mongoose supports a special `$*` syntax to [populate](/docs/populate.html) all elements in a map.
+    For example, suppose your `socialMediaHandles` map contains a `ref`:
+
+    ```javascript
+    const userSchema = new Schema({
+      socialMediaHandles: {
+        type: Map,
+        of: new Schema({
+          handle: String,
+          oauth: {
+            type: ObjectId,
+            ref: 'OAuth'
+          }
+        })
+      }
+    });
+    const User = mongoose.model('User', userSchema);
+    ```
+
+    To populate every `socialMediaHandles` entry's `oauth` property, you should populate
+    on `socialMediaHandles.$*.oauth`:
+
+    ```javascript
+    const user = await User.findOne().populate('socialMediaHandles.$*.oauth');
+    ```
+
     <h3 id="getters"><a href="#getters">Getters</a></h3>
 
     Getters are like virtuals for paths defined in your schema. For example,

From 93238606311273336f3e58643318400c965aa1fe Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 17 Feb 2021 09:35:55 -0500
Subject: [PATCH 1718/2348] chore: release 5.11.17

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 658db73aa3e..c4948fa7b07 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.11.17 / 2021-02-17
+====================
+ * fix(populate): handle `perDocumentLimit` when multiple documents reference the same populated doc #9906
+ * fix(document): handle directly setting embedded document array element with projection #9909
+ * fix(map): cast ObjectId to string inside of MongooseMap #9938 [HunterKohler](https://github.com/HunterKohler)
+ * fix(model): use schema-level default collation for indexes if index doesn't have collation #9912
+ * fix(index.d.ts): make `SchemaTypeOptions#type` optional again to allow alternative typeKeys #9927
+ * fix(index.d.ts): support `{ type: String }` in schema definition when using SchemaDefinitionType generic #9911
+ * docs(populate+schematypes): document the `$*` syntax for populating every entry in a map #9907
+ * docs(connection): clarify that `Connection#transaction()` promise resolves to a command result #9919
+
 5.11.16 / 2021-02-12
 ====================
  * fix(document): skip applying array element setters when init-ing an array #9889
diff --git a/package.json b/package.json
index b63bd9a5b7e..9ac4f5ecb4d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.16",
+  "version": "5.11.17",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 65ae5c1cfc2660a488f77ddc33c139daeb5ea7d5 Mon Sep 17 00:00:00 2001
From: ShadiestGoat <shady@shadygoat.eu>
Date: Sat, 20 Feb 2021 22:27:50 +0000
Subject: [PATCH 1719/2348] Adds enforcing

---
 index.d.ts | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4d4a6ee49a4..3d5232c3a78 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1188,8 +1188,7 @@ declare module 'mongoose' {
     ? (typeof String | 'string' | 'String')
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = SchemaTypeOptions<T extends undefined ? any : T> |
-    SchemaDefinitionWithBuiltInClass<T> |
+  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> : SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |
     Schema<T extends Document ? T : Document<any>>[] |

From 73c04bade13e30d7be91f9af6c50b1792a62c0c3 Mon Sep 17 00:00:00 2001
From: ShadiestGoat <shady@shadygoat.eu>
Date: Sat, 20 Feb 2021 22:29:45 +0000
Subject: [PATCH 1720/2348] *style*

---
 index.d.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 3d5232c3a78..20771547dec 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1188,7 +1188,8 @@ declare module 'mongoose' {
     ? (typeof String | 'string' | 'String')
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> : SchemaTypeOptions<T extends undefined ? any : T> |
+  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> : 
+    SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |
     Schema<T extends Document ? T : Document<any>>[] |

From d1576a0de425ccfee771a60907eec600c420f00a Mon Sep 17 00:00:00 2001
From: ShadiestGoat <shady@shadygoat.eu>
Date: Sun, 21 Feb 2021 00:32:38 +0000
Subject: [PATCH 1721/2348] no whitespace

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 20771547dec..668a7826cf1 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1188,7 +1188,7 @@ declare module 'mongoose' {
     ? (typeof String | 'string' | 'String')
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> : 
+  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |

From 78efd9ffff07ba176b27bbcac7b566c47302975e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 20 Feb 2021 19:44:35 -0500
Subject: [PATCH 1722/2348] feat(populate): add `transform` option that
 Mongoose will call on every populated doc

Fix #3775
---
 lib/helpers/populate/assignVals.js | 32 ++++++----
 lib/model.js                       |  1 +
 lib/query.js                       |  1 +
 test/model.populate.test.js        | 97 ++++++++++++++++++++++++++++++
 4 files changed, 120 insertions(+), 11 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index a09b1007473..2be723792d3 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -12,7 +12,7 @@ const utils = require('../../utils');
 
 module.exports = function assignVals(o) {
   // Options that aren't explicitly listed in `populateOptions`
-  const userOptions = get(o, 'allOptions.options.options');
+  const userOptions = Object.assign({}, get(o, 'allOptions.options.options'), get(o, 'allOptions.options'));
   // `o.options` contains options explicitly listed in `populateOptions`, like
   // `match` and `limit`.
   const populateOptions = Object.assign({}, o.options, userOptions, {
@@ -34,6 +34,8 @@ module.exports = function assignVals(o) {
   const options = o.options;
   const count = o.count && o.isVirtual;
 
+  let i;
+
   function setValue(val) {
     if (count) {
       return val;
@@ -61,14 +63,14 @@ module.exports = function assignVals(o) {
         val[i] = ret[i];
       }
 
-      return valueFilter(val[0], options, populateOptions, populatedModel);
+      return valueFilter(val[0], options, populateOptions, o.allIds[i]);
     } else if (o.justOne === false && !Array.isArray(val)) {
-      return valueFilter([val], options, populateOptions, populatedModel);
+      return valueFilter([val], options, populateOptions, o.allIds[i]);
     }
-    return valueFilter(val, options, populateOptions, populatedModel);
+    return valueFilter(val, options, populateOptions, o.allIds[i]);
   }
 
-  for (let i = 0; i < docs.length; ++i) {
+  for (i = 0; i < docs.length; ++i) {
     const existingVal = mpath.get(o.path, docs[i], lookupLocalFields);
     if (existingVal == null && !getVirtual(o.originalModel.schema, o.path)) {
       continue;
@@ -195,15 +197,19 @@ function numDocs(v) {
  * that population mapping can occur.
  */
 
-function valueFilter(val, assignmentOpts, populateOptions) {
+function valueFilter(val, assignmentOpts, populateOptions, allIds) {
+  const userSpecifiedTransform = typeof populateOptions.transform === 'function';
+  const transform = userSpecifiedTransform ? populateOptions.transform : noop;
   if (Array.isArray(val)) {
     // find logic
     const ret = [];
     const numValues = val.length;
     for (let i = 0; i < numValues; ++i) {
-      const subdoc = val[i];
-      if (!isPopulatedObject(subdoc) && (!populateOptions.retainNullValues || subdoc != null)) {
+      let subdoc = val[i];
+      if (!isPopulatedObject(subdoc) && (!populateOptions.retainNullValues || subdoc != null) && !userSpecifiedTransform) {
         continue;
+      } else if (userSpecifiedTransform) {
+        subdoc = transform(isPopulatedObject(subdoc) ? subdoc : null, allIds[i]);
       }
       maybeRemoveId(subdoc, assignmentOpts);
       ret.push(subdoc);
@@ -227,7 +233,7 @@ function valueFilter(val, assignmentOpts, populateOptions) {
   // findOne
   if (isPopulatedObject(val)) {
     maybeRemoveId(val, assignmentOpts);
-    return val;
+    return transform(val, allIds);
   }
 
   if (val instanceof Map) {
@@ -235,12 +241,12 @@ function valueFilter(val, assignmentOpts, populateOptions) {
   }
 
   if (populateOptions.justOne === true) {
-    return (val == null ? val : null);
+    return val == null ? transform(val, allIds) : transform(null, allIds);
   }
   if (populateOptions.justOne === false) {
     return [];
   }
-  return val == null ? val : null;
+  return val == null ? transform(val, allIds) : transform(null, allIds);
 }
 
 /*!
@@ -271,4 +277,8 @@ function isPopulatedObject(obj) {
     obj.$isMongooseMap ||
     obj.$__ != null ||
     leanPopulateMap.has(obj);
+}
+
+function noop(v) {
+  return v;
 }
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index a7564bbc2c3..2b5fbb3b5f2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4268,6 +4268,7 @@ Model.geoSearch = function(conditions, options, callback) {
  * @param {Boolean} [options.skipInvalidIds=false] By default, Mongoose throws a cast error if `localField` and `foreignField` schemas don't line up. If you enable this option, Mongoose will instead filter out any `localField` properties that cannot be casted to `foreignField`'s schema type.
  * @param {Number} [options.perDocumentLimit=null] For legacy reasons, `limit` with `populate()` may give incorrect results because it only executes a single query for every document being populated. If you set `perDocumentLimit`, Mongoose will ensure correct `limit` per document by executing a separate query for each document to `populate()`. For example, `.find().populate({ path: 'test', perDocumentLimit: 2 })` will execute 2 additional queries if `.find()` returns 2 documents.
  * @param {Object} [options.options=null] Additional options like `limit` and `lean`.
+ * @param {Function} [options.transform=null] Function that Mongoose will call on every populated document that allows you to transform the populated document.
  * @param {Function} [callback(err,doc)] Optional callback, executed upon completion. Receives `err` and the `doc(s)`.
  * @return {Promise}
  * @api public
diff --git a/lib/query.js b/lib/query.js
index 371caf40c58..518a764a110 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4623,6 +4623,7 @@ function castDoc(query, overwrite) {
  * @param {boolean} [options.getters=false] if true, Mongoose will call any getters defined on the `localField`. By default, Mongoose gets the raw value of `localField`. For example, you would need to set this option to `true` if you wanted to [add a `lowercase` getter to your `localField`](/docs/schematypes.html#schematype-options).
  * @param {boolean} [options.clone=false] When you do `BlogPost.find().populate('author')`, blog posts with the same author will share 1 copy of an `author` doc. Enable this option to make Mongoose clone populated docs before assigning them.
  * @param {Object|Function} [options.match=null] Add an additional filter to the populate query. Can be a filter object containing [MongoDB query syntax](https://docs.mongodb.com/manual/tutorial/query-documents/), or a function that returns a filter object.
+ * @param {Function} [options.transform=null] Function that Mongoose will call on every populated document that allows you to transform the populated document.
  * @param {Object} [options.options=null] Additional options like `limit` and `lean`.
  * @see population ./populate.html
  * @see Query#select #query_Query-select
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 07639c5b104..ec262c64672 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9981,4 +9981,101 @@ describe('model: populate:', function() {
       assert.deepEqual(posts[1].toObject().commentsIds.map(c => c.content), ['Im used in two posts', 'Nice second post']);
     });
   });
+
+  it('supports `transform` option (gh-3375)', function() {
+    const parentSchema = new Schema({
+      name: String,
+      children: [{ type: 'ObjectId', ref: 'Child' }],
+      child: { type: 'ObjectId', ref: 'Child' }
+    });
+    const Parent = db.model('Parent', parentSchema);
+
+    const Child = db.model('Child', Schema({ name: String }));
+
+    return co(function*() {
+      const children = yield Child.create([{ name: 'Luke' }, { name: 'Leia' }]);
+      let p = yield Parent.create({
+        name: 'Anakin',
+        children: children,
+        child: children[0]._id
+      });
+
+      let called = [];
+
+      p = yield Parent.findById(p).populate({
+        path: 'children',
+        transform: function(doc, id) {
+          called.push({
+            doc: doc,
+            id: id
+          });
+
+          return id;
+        }
+      });
+
+      assert.equal(called.length, 2);
+      assert.equal(called[0].doc.name, 'Luke');
+      assert.equal(called[0].id.toHexString(), children[0]._id.toHexString());
+
+      assert.equal(called[1].doc.name, 'Leia');
+      assert.equal(called[1].id.toHexString(), children[1]._id.toHexString());
+
+      called = [];
+      p = yield Parent.findById(p).populate({
+        path: 'child',
+        transform: function(doc, id) {
+          called.push({
+            doc: doc,
+            id: id
+          });
+
+          return id;
+        }
+      });
+
+      assert.equal(called.length, 1);
+      assert.equal(called[0].doc.name, 'Luke');
+      assert.equal(called[0].id.toHexString(), children[0]._id.toHexString());
+
+      const newId = new mongoose.Types.ObjectId();
+      yield Parent.updateOne({ _id: p._id }, { $push: { children: newId } });
+
+      called = [];
+      p = yield Parent.findById(p).populate({
+        path: 'children',
+        transform: function(doc, id) {
+          called.push({
+            doc: doc,
+            id: id
+          });
+
+          return id;
+        }
+      });
+      assert.equal(called.length, 3);
+      assert.strictEqual(called[2].doc, null);
+      assert.equal(called[2].id.toHexString(), newId.toHexString());
+
+      assert.equal(p.children[2].toHexString(), newId.toHexString());
+
+      yield Parent.updateOne({ _id: p._id }, { $set: { child: newId } });
+      called = [];
+      p = yield Parent.findById(p).populate({
+        path: 'child',
+        transform: function(doc, id) {
+          called.push({
+            doc: doc,
+            id: id
+          });
+
+          return id;
+        }
+      });
+
+      assert.equal(called.length, 1);
+      assert.strictEqual(called[0].doc, null);
+      assert.equal(called[0].id.toHexString(), newId.toHexString());
+    });
+  });
 });

From 8a7d33eab4663fdba2292bbf678c73d674123262 Mon Sep 17 00:00:00 2001
From: ShadiestGoat <48590492+ShadiestGoat@users.noreply.github.com>
Date: Sun, 21 Feb 2021 01:55:30 +0000
Subject: [PATCH 1723/2348] Silly ol' me forgot about the function type aha

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 668a7826cf1..58cd9517a2a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1188,7 +1188,7 @@ declare module 'mongoose' {
     ? (typeof String | 'string' | 'String')
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> :
+  type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |

From 81933619c3515efa42a6b1c67aefa8ab55922ced Mon Sep 17 00:00:00 2001
From: Denis Bardadym <denis.bardadym@check24.de>
Date: Sun, 21 Feb 2021 13:52:17 +0100
Subject: [PATCH 1724/2348] Improve types of Model.deleteMany and
 Model.deleteOne

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4d4a6ee49a4..bd394f0c61a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -659,14 +659,14 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: any, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<any, T>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.

From 49cc37e2da11ff39f7bddc9223b891d0c2d8f7e3 Mon Sep 17 00:00:00 2001
From: Denis Bardadym <denis.bardadym@check24.de>
Date: Sun, 21 Feb 2021 15:50:17 +0100
Subject: [PATCH 1725/2348] Fix result types of update* functions

---
 index.d.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index bd394f0c61a..916ffb9ecf7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -835,13 +835,13 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<mongodb.WriteOpResult['result'], T>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<mongodb.UpdateWriteOpResult['result'], T>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<mongodb.UpdateWriteOpResult['result'], T>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): Query<Array<T>, T>;

From e85e478ba888bebb9a30a88acf89809dc05843c9 Mon Sep 17 00:00:00 2001
From: ShadiestGoat <48590492+ShadiestGoat@users.noreply.github.com>
Date: Mon, 22 Feb 2021 01:45:12 +0000
Subject: [PATCH 1726/2348] SchemaTypeOptions now works!

I forgot to add this before I guess. This way, if T is a string/number/function, then it shows it as well. If it is another type, it also shows it (which is why it isn't any).
---
 index.d.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 58cd9517a2a..6bd1ef37fbd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1188,7 +1188,8 @@ declare module 'mongoose' {
     ? (typeof String | 'string' | 'String')
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
+  type SchemaDefinitionProperty<T = undefined> = type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function ?
+    SchemaDefinitionWithBuiltInClass<T> | SchemaTypeOptions<T> :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |

From f26939b961952ba4807cbfead1c005d80c5f7809 Mon Sep 17 00:00:00 2001
From: ShadiestGoat <shady@shadygoat.eu>
Date: Mon, 22 Feb 2021 01:55:14 +0000
Subject: [PATCH 1727/2348] enforcing onto SchemaTypeOptions

---
 index.d.ts | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 668a7826cf1..b951f5e1937 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1182,13 +1182,14 @@ declare module 'mongoose' {
     virtualpath(name: string): VirtualType | null;
   }
 
-  type SchemaDefinitionWithBuiltInClass<T> = T extends number
+  type SchemaDefinitionWithBuiltInClass<T extends number | string | Function> = T extends number
     ? (typeof Number | 'number' | 'Number')
     : T extends string
     ? (typeof String | 'string' | 'String')
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = T extends string | number ? SchemaDefinitionWithBuiltInClass<T> :
+  type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function
+    ? (SchemaDefinitionWithBuiltInClass<T> | SchemaTypeOptions<T>) :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
     Schema<T extends Document ? T : Document<any>> |
@@ -1365,7 +1366,7 @@ declare module 'mongoose' {
   }
 
   interface SchemaTypeOptions<T> {
-    type?: T | SchemaDefinitionWithBuiltInClass<T>;
+    type?: T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> : T;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;

From 6fe73016c982c8029bf6f21d50a9cd0843eeda39 Mon Sep 17 00:00:00 2001
From: Ting-Wei Lan <tingweilan@noodoe.com>
Date: Mon, 22 Feb 2021 18:07:25 +0800
Subject: [PATCH 1728/2348] fix(connection): fix promise chaining for openUri

When a user calls openUri and attaches more than one callback to its
return value with 'then' method, it should be able to pass the result of
the first callback to the second one. Currently, openUri always pass
'undefined' to the second callback, making it behave differently from a
regular promise. This is unlikely to be an expected behaviour.

To fix it, modify openUri to propagate the return value of the
user-provided callback to the 'then' method of the promise.
---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 83ff8f8c9a0..178bfda8f5a 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -858,7 +858,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
   this.then = function(resolve, reject) {
     return this.$initialConnection.then(() => {
       if (typeof resolve === 'function') {
-        resolve(_this);
+        return resolve(_this);
       }
     }, reject);
   };

From f87da262c1e5d7bf56aa06ded8060455d71b4ce9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 10:52:30 -0500
Subject: [PATCH 1729/2348] fix(index.d.ts): add non-generic versions of
 `Model.create()` for better autocomplete

Fix #9928
---
 index.d.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 4d4a6ee49a4..2ac788ca0db 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -630,6 +630,10 @@ declare module 'mongoose' {
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T>;
 
     /** Creates a new document or documents */
+    create(doc: T | DocumentDefinition<T>): Promise<T>;
+    create(docs: (T | DocumentDefinition<T>)[], options?: SaveOptions): Promise<T[]>;
+    create(docs: (T | DocumentDefinition<T>)[], callback: (err: CallbackError, docs: T[]) => void): void;
+    create(doc: T | DocumentDefinition<T>, callback: (err: CallbackError, doc: T) => void): void;
     create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<T[]>;
     create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
     create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<T[]>;

From ffbf2f7d657dacd2dbcf33e334f0ceb253783a13 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 11:30:45 -0500
Subject: [PATCH 1730/2348] fix(connection): remove `db` events deprecation
 warning if `useUnifiedTopology = true`

Fix #9930
---
 lib/connection.js | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 83ff8f8c9a0..ecf375b9f28 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -940,14 +940,15 @@ function _setClient(conn, client, options, dbName) {
   }
 
   // Backwards compat for mongoose 4.x
-  db.on('reconnect', function() {
-    _handleReconnect();
-  });
   db.s.topology.on('reconnectFailed', function() {
     conn.emit('reconnectFailed');
   });
 
   if (!options.useUnifiedTopology) {
+    db.on('reconnect', function() {
+      _handleReconnect();
+    });
+
     db.s.topology.on('left', function(data) {
       conn.emit('left', data);
     });
@@ -963,11 +964,16 @@ function _setClient(conn, client, options, dbName) {
       conn.emit('attemptReconnect');
     });
   }
-  if (!options.useUnifiedTopology || !type.startsWith('ReplicaSet')) {
+  if (!options.useUnifiedTopology) {
     db.on('close', function() {
       // Implicitly emits 'disconnected'
       conn.readyState = STATES.disconnected;
     });
+  } else if (!type.startsWith('ReplicaSet')) {
+    client.on('close', function() {
+      // Implicitly emits 'disconnected'
+      conn.readyState = STATES.disconnected;
+    });
   }
 
   if (!options.useUnifiedTopology) {
@@ -977,11 +983,11 @@ function _setClient(conn, client, options, dbName) {
         conn.readyState = STATES.disconnected;
       }
     });
-  }
 
-  db.on('timeout', function() {
-    conn.emit('timeout');
-  });
+    db.on('timeout', function() {
+      conn.emit('timeout');
+    });
+  }
 
   delete conn.then;
   delete conn.catch;

From 60f522b62cef1b1d63f8d241d7d6c9bae0d863f4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 11:43:18 -0500
Subject: [PATCH 1731/2348] fix(index.d.ts): allow explicitly overwriting
 `toObject()` return type for backwards compatibility

Fix #9944
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 2ac788ca0db..cab7171cafb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -567,9 +567,11 @@ declare module 'mongoose' {
 
     /** The return value of this method is used in calls to JSON.stringify(doc). */
     toJSON(options?: ToObjectOptions): LeanDocument<this>;
+    toJSON<T>(options?: ToObjectOptions): T;
 
     /** Converts this document into a plain-old JavaScript object ([POJO](https://masteringjs.io/tutorials/fundamentals/pojo)). */
     toObject(options?: ToObjectOptions): LeanDocument<this>;
+    toObject<T>(options?: ToObjectOptions): T;
 
     /** Clears the modified state on the specified path. */
     unmarkModified(path: string): void;
@@ -1725,6 +1727,7 @@ declare module 'mongoose' {
 
       /** Returns a native js Array. */
       toObject(options?: ToObjectOptions): any;
+      toObject<T>(options?: ToObjectOptions): T;
 
       /** Wraps [`Array#unshift`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/unshift) with proper change tracking. */
       unshift(...args: any[]): number;

From 6a12b6cadd78765b74886e14ad1c82b17af08a0a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 11:51:15 -0500
Subject: [PATCH 1732/2348] test(populate): make #9906 test more robust to
 ordering issues

---
 test/model.populate.test.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 07639c5b104..4a897f477b0 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -9973,7 +9973,9 @@ describe('model: populate:', function() {
         { title: 'Second post', commentsIds: [commonComment, comments[1]] }
       ]);
 
-      posts = yield Post.find().populate({ path: 'commentsIds', perDocumentLimit: 2, sort: { content: 1 } });
+      posts = yield Post.find().
+        sort({ title: 1 }).
+        populate({ path: 'commentsIds', perDocumentLimit: 2, sort: { content: 1 } });
       assert.equal(posts.length, 2);
       assert.ok(!Array.isArray(posts[0].commentsIds[0]));
 

From 9f6c7ea626f9d8227154eaa1847b334646d68256 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 13:59:33 -0500
Subject: [PATCH 1733/2348] docs: correctly handle multiple `&gt` in API
 descriptions

Fix #9940
---
 docs/source/api.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/source/api.js b/docs/source/api.js
index 0f78017e634..a80c9419bb9 100644
--- a/docs/source/api.js
+++ b/docs/source/api.js
@@ -164,7 +164,7 @@ function parse() {
 
       ctx.description = prop.description.full.
         replace(/<br \/>/ig, ' ').
-        replace(/&gt;/i, '>');
+        replace(/&gt;/ig, '>');
       ctx.description = highlight(ctx.description);
 
       data.props.push(ctx);

From 3d2345f524437d09eeb0c6423ea8b044b5818080 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 16:22:25 -0500
Subject: [PATCH 1734/2348] fix(connection): set connection state to
 `disconnected` if connecting string failed to parse

Fix #9921
---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 0f646b72b42..2f6214b088b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -832,7 +832,6 @@ Connection.prototype.openUri = function(uri, options, callback) {
     _this.client = client;
     client.connect((error) => {
       if (error) {
-        _this.readyState = STATES.disconnected;
         return reject(error);
       }
 
@@ -846,6 +845,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
   this.$initialConnection = Promise.all([promise, parsePromise]).
     then(res => res[0]).
     catch(err => {
+      this.readyState = STATES.disconnected;
       if (err != null && err.name === 'MongoServerSelectionError') {
         err = serverSelectionError.assimilateError(err);
       }

From b5c6a506f9b59a61979fab502db5ac1b58b81292 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 17:09:34 -0500
Subject: [PATCH 1735/2348] fix(index.d.ts): add `PopulatedDoc` type to make it
 easier to define populated docs in interfaces

Fix #9818
---
 index.d.ts                   | 20 ++++++++++++++++++++
 test/typescript/main.test.js |  8 ++++++++
 test/typescript/populate.ts  | 20 ++++++++++++++++++++
 3 files changed, 48 insertions(+)
 create mode 100644 test/typescript/populate.ts

diff --git a/index.d.ts b/index.d.ts
index fa35e3ac341..3244b0f417d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1501,6 +1501,26 @@ declare module 'mongoose' {
     [other: string]: any;
   }
 
+  export type RefType =
+    | number
+    | string
+    | Buffer
+    | undefined
+    | mongoose.Types.ObjectId
+    | mongoose.Types.Buffer
+    | typeof mongoose.Schema.Types.Number
+    | typeof mongoose.Schema.Types.String
+    | typeof mongoose.Schema.Types.Buffer
+    | typeof mongoose.Schema.Types.ObjectId;
+
+  /**
+   * Reference another Model
+   */
+  export type PopulatedDoc<
+    PopulatedType,
+    RawId extends RefType = (PopulatedType extends { _id?: RefType; } ? NonNullable<PopulatedType['_id']> : mongoose.Types.ObjectId) | undefined
+    > = PopulatedType | RawId;
+
   interface IndexOptions {
     background?: boolean,
     expires?: number | string
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 7dd5e51bef9..e6fc87c062a 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -190,6 +190,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('populate', function() {
+    const errors = runTest('populate.ts', { strict: true });
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file, configOverride) {
diff --git a/test/typescript/populate.ts b/test/typescript/populate.ts
new file mode 100644
index 00000000000..b7bb1674140
--- /dev/null
+++ b/test/typescript/populate.ts
@@ -0,0 +1,20 @@
+import { Schema, model, Document, PopulatedDoc } from 'mongoose';
+
+interface IChild extends Document { name?: string }
+
+const childSchema: Schema = new Schema({ name: String });
+const Child = model<IChild>('Child', childSchema);
+
+interface IParent extends Document {
+  child?: PopulatedDoc<IChild>,
+  name?: string
+}
+
+const Parent = model<IParent>('Parent', new Schema({
+  child: { type: 'ObjectId', ref: 'Child' },
+  name: String
+}));
+
+Parent.findOne({}).populate('child').orFail().then((doc: IParent) => {
+  doc.child.name.trim();
+});
\ No newline at end of file

From 321ead5692fb3cdf2a3133df78bf2b851304ab29 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Feb 2021 17:40:07 -0500
Subject: [PATCH 1736/2348] fix(index.d.ts): some cleanup re: #9850 #9896

---
 index.d.ts                 | 33 ++++++---------------------------
 test/typescript/queries.ts |  2 +-
 2 files changed, 7 insertions(+), 28 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 1728c34e81e..8e64f799d7e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,10 +99,10 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document, TQueryHelpers = Record<string, any>>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
-  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = Record<string, any>>(
+  export function model<T extends Document, TQueryHelpers = any>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
+  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = any>(
     name: string,
-    schema?: Schema<T, U, TQueryHelpers>,
+    schema?: Schema<T, U>,
     collection?: string,
     skipInit?: boolean
   ): U;
@@ -592,30 +592,9 @@ declare module 'mongoose' {
     validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
   }
 
-  type CreateDoc<T> = Omit<
-    {
-      [P in keyof T as
-        T[P] extends Function
-        ? never
-        : P
-      ]: T[P] extends (Array<any> | Record<string, any>)
-        ? CreateDoc<T[P]>
-        : T[P];
-    },
-    | '$locals'
-    | '$op'
-    | '$where'
-    | 'db'
-    | 'isNew'
-    | 'modelName'
-    | 'schema'
-    | 'baseModelName'
-    | 'errors'
-  >;
-
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document, TQueryHelpers = Record<string, any>> extends NodeJS.EventEmitter {
+  interface Model<T extends Document, TQueryHelpers = any> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
@@ -1073,7 +1052,7 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined, TQueryHelpers = Record<string, any>> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1176,7 +1155,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: TQueryHelpers;
+    query: { [name: string]: (this: M, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index bb3583b1e36..da269afbb75 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -4,7 +4,7 @@ interface QueryHelpers {
   byName(name: string): Query<Array<ITest>, ITest, QueryHelpers>;
 }
 
-const schema: Schema<ITest, Model<ITest>, undefined, QueryHelpers> = new Schema({ name: { type: 'String' }, tags: [String] });
+const schema: Schema<ITest, Model<ITest>> = new Schema({ name: { type: 'String' }, tags: [String] });
 
 schema.query.byName = function(name: string): Query<Array<ITest>, ITest, QueryHelpers> {
   return this.find({ name });

From 899ab333e9ae39f1ca2c1a3164ecc9ec07b97036 Mon Sep 17 00:00:00 2001
From: Krishna Moorthy <akrishnamoorthy007@gmail.com>
Date: Tue, 23 Feb 2021 12:17:23 +0530
Subject: [PATCH 1737/2348] small error fix

---
 docs/populate.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/populate.pug b/docs/populate.pug
index a9cee2d1031..b0c193d3f98 100644
--- a/docs/populate.pug
+++ b/docs/populate.pug
@@ -220,7 +220,7 @@ block content
         // prints "The author is Ian Fleming"
 
         console.log('The authors age is %s', story.author.age);
-        // prints "The authors age is null'
+        // prints "The authors age is null"
       });
     ```
 

From a3c9018e24df0e77b9dc3754fb54d038617c009e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 23 Feb 2021 15:16:58 -0500
Subject: [PATCH 1738/2348] fix(index.d.ts): allow using `Schema.Types.*` for
 as SchemaDefinitionProperty re: #9958

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3244b0f417d..9f7e1915146 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1189,9 +1189,9 @@ declare module 'mongoose' {
   }
 
   type SchemaDefinitionWithBuiltInClass<T extends number | string | Function> = T extends number
-    ? (typeof Number | 'number' | 'Number')
+    ? (typeof Number | 'number' | 'Number' | typeof Schema.Types.Number)
     : T extends string
-    ? (typeof String | 'string' | 'String')
+    ? (typeof String | 'string' | 'String' | typeof Schema.Types.String)
     : (Function | string);
 
   type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function

From b69413a750adeab37de2f998469ea085f848e645 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 23 Feb 2021 15:25:38 -0500
Subject: [PATCH 1739/2348] chore: remove travis

---
 .travis.yml | 25 -------------------------
 1 file changed, 25 deletions(-)
 delete mode 100644 .travis.yml

diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index ad98e77aa83..00000000000
--- a/.travis.yml
+++ /dev/null
@@ -1,25 +0,0 @@
-language: node_js
-sudo: false
-node_js: [14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4]
-install:
-  - travis_retry npm install
-before_script:
-  - wget http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
-  - tar -zxvf mongodb-linux-x86_64-ubuntu1604-4.0.2.tgz
-  - mkdir -p ./data/db/27017
-  - mkdir -p ./data/db/27000
-  - printf "\n--timeout 8000" >> ./test/mocha.opts
-  - ./mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
-  - export PATH=`pwd`/mongodb-linux-x86_64-ubuntu1604-4.0.2/bin/:$PATH
-  - sleep 2
-  - mongod --version
-  - mkdir ./test/typescript/node_modules
-  - ln -s `pwd` ./test/typescript/node_modules/mongoose
-matrix:
-  include:
-    - name: "👕Linter"
-      node_js: 10
-      before_script: skip
-      script: npm run lint
-notifications:
-  email: false

From 811a52a20252b41f3fdd7d34353fd430384ce059 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 23 Feb 2021 15:35:19 -0500
Subject: [PATCH 1740/2348] chore: release 5.11.18

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c4948fa7b07..6e890ba35d5 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.11.18 / 2021-02-23
+====================
+ * fix(connection): set connection state to `disconnected` if connecting string failed to parse #9921
+ * fix(connection): remove `db` events deprecation warning if `useUnifiedTopology = true` #9930
+ * fix(connection): fix promise chaining for openUri #9960 [lantw44](https://github.com/lantw44)
+ * fix(index.d.ts): add `PopulatedDoc` type to make it easier to define populated docs in interfaces #9818
+ * fix(index.d.ts): allow explicitly overwriting `toObject()` return type for backwards compatibility #9944
+ * fix(index.d.ts): correctly throw error when interface path type doesn't line up with schema path type #9958 [ShadiestGoat](https://github.com/ShadiestGoat)
+ * fix(index.d.ts): remove `any` from `deleteX()` and `updateX()` query params and return values #9959 [btd](https://github.com/btd)
+ * fix(index.d.ts): add non-generic versions of `Model.create()` for better autocomplete #9928
+ * docs: correctly handle multiple `&gt` in API descriptions #9940
+
 5.11.17 / 2021-02-17
 ====================
  * fix(populate): handle `perDocumentLimit` when multiple documents reference the same populated doc #9906
diff --git a/package.json b/package.json
index 9ac4f5ecb4d..5312c3c0411 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.17",
+  "version": "5.11.18",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From e5e2937f8f0cd981308f5361cfb8e1b143b75e33 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 25 Feb 2021 09:55:44 -0500
Subject: [PATCH 1741/2348] fix(populate): mostly working `transform` option
 for virtual populate re: #3775

---
 lib/helpers/populate/assignVals.js | 11 ++--
 test/model.populate.test.js        | 84 ++++++++++++++++++++++++++++++
 2 files changed, 91 insertions(+), 4 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 2be723792d3..d5e3ccef04b 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -25,6 +25,7 @@ module.exports = function assignVals(o) {
 
   // replace the original ids in our intermediate _ids structure
   // with the documents found by query
+  o.allIds = [].concat(o.allIds);
   assignRawDocsToIdStructure(o.rawIds, o.rawDocs, o.rawOrder, populateOptions);
 
   // now update the original documents being populated using the
@@ -44,6 +45,8 @@ module.exports = function assignVals(o) {
       return val.val;
     }
 
+    const _allIds = o.allIds[i];
+
     if (o.justOne === true && Array.isArray(val)) {
       // Might be an embedded discriminator (re: gh-9244) with multiple models, so make sure to pick the right
       // model before assigning.
@@ -63,11 +66,11 @@ module.exports = function assignVals(o) {
         val[i] = ret[i];
       }
 
-      return valueFilter(val[0], options, populateOptions, o.allIds[i]);
+      return valueFilter(val[0], options, populateOptions, _allIds);
     } else if (o.justOne === false && !Array.isArray(val)) {
-      return valueFilter([val], options, populateOptions, o.allIds[i]);
+      return valueFilter([val], options, populateOptions, _allIds);
     }
-    return valueFilter(val, options, populateOptions, o.allIds[i]);
+    return valueFilter(val, options, populateOptions, _allIds);
   }
 
   for (i = 0; i < docs.length; ++i) {
@@ -209,7 +212,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
       if (!isPopulatedObject(subdoc) && (!populateOptions.retainNullValues || subdoc != null) && !userSpecifiedTransform) {
         continue;
       } else if (userSpecifiedTransform) {
-        subdoc = transform(isPopulatedObject(subdoc) ? subdoc : null, allIds[i]);
+        subdoc = transform(isPopulatedObject(subdoc) ? subdoc : null, allIds);
       }
       maybeRemoveId(subdoc, assignmentOpts);
       ret.push(subdoc);
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index ec262c64672..da7cd59ea4a 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10078,4 +10078,88 @@ describe('model: populate:', function() {
       assert.equal(called[0].id.toHexString(), newId.toHexString());
     });
   });
+
+  it('transform with virtual populate, justOne = true (gh-3375)', function() {
+    const parentSchema = new Schema({
+      name: String
+    });
+    parentSchema.virtual('child', {
+      ref: 'Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      justOne: true
+    });
+    const Parent = db.model('Parent', parentSchema);
+
+    const Child = db.model('Child', Schema({ name: String, parentId: 'ObjectId' }));
+
+    return co(function*() {
+      let p = yield Parent.create({ name: 'Anakin' });
+      const child = yield Child.create({ name: 'Luke', parentId: p._id });
+
+      let called = [];
+
+      p = yield Parent.findById(p).populate({
+        path: 'child',
+        transform: function(doc, id) {
+          called.push({
+            doc: doc,
+            id: id
+          });
+
+          return id;
+        }
+      });
+
+      assert.equal(called.length, 1);
+      assert.strictEqual(called[0].doc.parentId.toHexString(), p._id.toHexString());
+      assert.equal(called[0].id.toHexString(), p._id.toHexString());
+    });
+  });
+
+  it('transform with virtual populate, justOne = false (gh-3375) XYZ', function() {
+    const parentSchema = new Schema({
+      name: String
+    });
+    parentSchema.virtual('children', {
+      ref: 'Child',
+      localField: '_id',
+      foreignField: 'parentId',
+      justOne: false
+    });
+    const Parent = db.model('Parent', parentSchema);
+
+    const Child = db.model('Child', Schema({ name: String, parentId: 'ObjectId' }));
+
+    return co(function*() {
+      let p = yield Parent.create({ name: 'Anakin' });
+      const children = yield Child.create([
+        { name: 'Luke', parentId: p._id },
+        { name: 'Leia', parentId: p._id }
+      ]);
+
+      let called = [];
+
+      p = yield Parent.findById(p).populate({
+        path: 'children',
+        transform: function(doc, id) {
+          called.push({
+            doc: doc,
+            id: id
+          });
+
+          return id;
+        }
+      });
+
+      assert.equal(called.length, 2);
+      assert.deepEqual(called.map(c => c.doc.name).sort(), ['Leia', 'Luke']);
+
+      assert.strictEqual(called[0].doc.parentId.toHexString(), p._id.toHexString());
+      assert.equal(called[0].id.toHexString(), p._id.toHexString());
+
+      assert.strictEqual(called[1].doc.parentId.toHexString(), p._id.toHexString());
+      assert.equal(called[1].id.toHexString(), p._id.toHexString());
+    });
+  });
 });

From f7c3261534cf79a156b6a102da31d3c5a04b98ad Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 27 Feb 2021 23:01:25 +0200
Subject: [PATCH 1742/2348] feat(model): Model.buildBulkWriteOperations(...)
 and base for Model.bulkSave(...)

---
 test/model.test.js | 163 +++++++++++++++++++++++++++++++++++++--------
 1 file changed, 134 insertions(+), 29 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 7c027431a7f..aa8ca80c8c1 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7084,6 +7084,99 @@ describe('Model', function() {
     });
   });
 
+  describe('buildBulkWriteOperations', () => {
+    it('builds write operations', () => {
+      return co(function*() {
+
+        const userSchema = new Schema({
+          name: { type: String }
+        });
+
+        const User = db.model('User', userSchema);
+
+        const users = [
+          new User({ name: 'Hafez1_gh-9673-1' }),
+          new User({ name: 'Hafez2_gh-9673-1' }),
+          new User({ name: 'I am the third name' })
+        ];
+
+        yield users[2].save();
+        users[2].name = 'I am the updated third name';
+
+        const writeOperations = User.buildBulkWriteOperations(users);
+
+        const desiredWriteOperations = [
+          { insertOne: { document: users[0] } },
+          { insertOne: { document: users[1] } },
+          { updateOne: { filter: { _id: users[2]._id }, update: { $set: { name: 'I am the updated third name' } } } }
+        ];
+
+        assert.deepEqual(
+          writeOperations,
+          desiredWriteOperations
+        );
+      });
+    });
+
+    it('throws an error when one document is invalid', () => {
+      const userSchema = new Schema({
+        name: { type: String, minLength: 5 }
+      });
+
+      const User = db.model('User', userSchema);
+
+      const users = [
+        new User({ name: 'a' }),
+        new User({ name: 'Hafez2_gh-9673-1' }),
+        new User({ name: 'b' })
+      ];
+
+      let err;
+      try {
+        User.buildBulkWriteOperations(users);
+      } catch (error) {
+        err = error;
+      }
+
+
+      assert.ok(err);
+    });
+
+    it('throws an error if documents is not an array', function() {
+      const userSchema = new Schema({
+        name: { type: String }
+      });
+
+      const User = db.model('User', userSchema);
+
+
+      assert.throws(
+        function() {
+          User.buildBulkWriteOperations(null);
+        },
+        /bulkSave expects an array of documents to be passed/
+      );
+    });
+    it('throws an error if one element is not a document', function() {
+      const userSchema = new Schema({
+        name: { type: String }
+      });
+
+      const User = db.model('User', userSchema);
+
+
+      assert.throws(
+        function() {
+          User.buildBulkWriteOperations([
+            new User({ name: 'Hafez' }),
+            { name: 'I am not a document' }
+          ]);
+        },
+        /documents\.1 was not a mongoose document/
+      );
+    });
+  });
+
   describe('bulkSave() (gh-9673)', function() {
     it('saves new documents', function() {
       return co(function* () {
@@ -7143,43 +7236,55 @@ describe('Model', function() {
         );
       });
     });
-    it('changes document state from `isNew` `false` to `true`');
-    it('changes documents state');
-    it('throws an error when a document is invalid');
-    it('throws an error when a document throws a unique error');
 
-    it('throws an error if documents is not an array', function() {
-      const userSchema = new Schema({
-        name: { type: String }
-      });
+    it('returns writeResult on success, err is null', () => {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String }
+        });
 
-      const User = db.model('User', userSchema);
+        const User = db.model('User', userSchema);
 
 
-      assert.throws(
-        function() {
-          User.bulkSave(null);
-        },
-        /bulkSave expects an array of documents to be passed/
-      );
-    });
-    it('throws an error if one element is not a document', function() {
-      const userSchema = new Schema({
-        name: { type: String }
+        yield User.insertMany([
+          new User({ name: 'Hafez1_gh-9673-2' }),
+          new User({ name: 'Hafez2_gh-9673-2' })
+        ]);
+
+        const users = yield User.find().sort('name');
+
+        users[0].name = 'Hafez1_gh-9673-2-updated';
+        users[1].name = 'Hafez2_gh-9673-2-updated';
+
+        const writeResult = yield User.bulkSave(users);
+        assert.ok(writeResult);
       });
+    });
+    it('returns err on failure, writeResult is null', () => {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String, unique: true }
+        });
 
-      const User = db.model('User', userSchema);
+        const User = db.model('User', userSchema);
+        yield User.init();
 
+        yield User.insertMany([
+          new User({ name: 'Hafez1_gh-9673-2' }),
+          new User({ name: 'Hafez2_gh-9673-2' })
+        ]);
 
-      assert.throws(
-        function() {
-          User.bulkSave([
-            new User({ name: 'Hafez' }),
-            { name: 'I am not a document' }
-          ]);
-        },
-        /documents\.1 was not a mongoose document/
-      );
+        const users = yield User.find().sort('name');
+
+        users[0].name = 'duplicate-name';
+        users[1].name = 'duplicate-name';
+
+        const err = yield User.bulkSave(users).then(() => null, err => err);
+        assert.ok(err);
+      });
     });
+    it('throws an error when a document throws a unique error');
+    it('changes document state from `isNew` `false` to `true`');
+    it('changes documents state');
   });
 });

From 6b7692b48c9d9559e7931599c94728f8cc2fc4ab Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 27 Feb 2021 23:06:27 +0200
Subject: [PATCH 1743/2348] fix failing tests

---
 lib/model.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 2120d18773d..f14e47256c7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3524,6 +3524,13 @@ Model.bulkWrite = function(ops, options, callback) {
  *
  */
 Model.bulkSave = function(documents) {
+  const writeOperations = this.buildBulkWriteOperations(documents);
+
+  // err.writeErrors.map(documentError=>documentError.err.op.q._id)
+  return this.bulkWrite(writeOperations);
+};
+
+Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents) {
   if (!Array.isArray(documents)) {
     throw new Error(`bulkSave expects an array of documents to be passed, received \`${documents}\` instead`);
   }
@@ -3533,6 +3540,10 @@ Model.bulkSave = function(documents) {
     if (!(document instanceof Document)) {
       throw new Error(`documents.${i} was not a mongoose document, documents must be an array of mongoose documents (instanceof mongoose.Document).`);
     }
+    const validationError = document.validateSync();
+    if (validationError) {
+      throw validationError;
+    }
 
     const changes = document.getChanges();
     if (document.isNew) {
@@ -3551,7 +3562,7 @@ Model.bulkSave = function(documents) {
     return accumulator;
   }, []);
 
-  return this.bulkWrite(writeOperations);
+  return writeOperations;
 };
 
 /**

From 97ccd437b326e43ee13c33b15a4cb9ba32438783 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Mar 2021 11:09:22 -0500
Subject: [PATCH 1744/2348] chore: update opencollective sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index 75ffbb0dfb7..b975e44bdba 100644
--- a/index.pug
+++ b/index.pug
@@ -169,9 +169,6 @@ html(lang='en')
               <a rel="sponsored" href="https://localizejs.com/">
                 <img class="sponsor" src="https://images.opencollective.com/localize/bb2cd4d/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
-                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/payment-ninja-mongoose.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.codefirst.co.uk/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fdde88120-e914-11e8-a662-278259d35390.png&height=100">
               </a>
@@ -259,9 +256,6 @@ html(lang='en')
               <a rel="sponsored" href="https://taxfreesnus.com/">
                 <img class="sponsor" src="https://images.opencollective.com/taxfreesnus-com/ebf869a/logo.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://www.nettikasinot.org/">
-                <img class="sponsor" src="https://images.opencollective.com/nettikasinot-org/bbd887f/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.pelisivut.com/">
                 <img class="sponsor" src="https://images.opencollective.com/pelisivut/04f08f2/logo/256.png" style="height: 100px">
               </a>

From 7036153feff7faec6dcd8d7ec4add90bc0e7341a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Mar 2021 17:38:04 -0500
Subject: [PATCH 1745/2348] chore: fix typescript version to fix tslint
 warnings

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 5312c3c0411..a18c2af0db4 100644
--- a/package.json
+++ b/package.json
@@ -63,7 +63,7 @@
     "pug": "2.0.3",
     "q": "1.5.1",
     "semver": "5.5.0",
-    "typescript": "4.x",
+    "typescript": "4.1.x",
     "uuid": "2.0.3",
     "uuid-parse": "1.0.0",
     "validator": "10.8.0",

From c1255fe505545f810d3781956edb5a5a9b0e8c07 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Mar 2021 17:38:24 -0500
Subject: [PATCH 1746/2348] test(timestamps): repro #9951

---
 test/timestamps.test.js | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index d37558cd3d2..b31369d6089 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -582,7 +582,7 @@ describe('timestamps', function() {
       });
     });
 
-    it('should have fields when create with findOneAndUpdate', function(done) {
+    it('sets timestamps on findOneAndUpdate', function(done) {
       Cat.findOneAndUpdate({ name: 'notexistname' }, { $set: {} }, { upsert: true, new: true }, function(err, doc) {
         assert.ok(doc.createdAt);
         assert.ok(doc.updatedAt);
@@ -591,6 +591,14 @@ describe('timestamps', function() {
       });
     });
 
+    it('sets timestamps on findOneAndReplace (gh-9951)', function() {
+      return Cat.findOneAndReplace({ name: 'notexistname' }, {}, { upsert: true, new: true }).then(doc => {
+        assert.ok(doc.createdAt);
+        assert.ok(doc.updatedAt);
+        assert.ok(doc.createdAt.getTime() === doc.updatedAt.getTime());
+      });
+    });
+
     it('should change updatedAt when save', function(done) {
       Cat.findOne({ name: 'newcat' }, function(err, doc) {
         const old = doc.updatedAt;

From aa463e6c3427d96a4d5ebbf4dff0d38e6a69e25c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Mar 2021 17:38:39 -0500
Subject: [PATCH 1747/2348] fix(timestamps): apply timestamps on
 `findOneAndReplace()`

Fix #9951
---
 lib/helpers/timestamps/setupTimestamps.js | 7 +++++++
 lib/query.js                              | 1 +
 2 files changed, 8 insertions(+)

diff --git a/lib/helpers/timestamps/setupTimestamps.js b/lib/helpers/timestamps/setupTimestamps.js
index 76140099df8..904485b0ba8 100644
--- a/lib/helpers/timestamps/setupTimestamps.js
+++ b/lib/helpers/timestamps/setupTimestamps.js
@@ -86,6 +86,7 @@ module.exports = function setupTimestamps(schema, timestamps) {
   _setTimestampsOnUpdate[symbols.builtInMiddleware] = true;
 
   const opts = { query: true, model: false };
+  schema.pre('findOneAndReplace', opts, _setTimestampsOnUpdate);
   schema.pre('findOneAndUpdate', opts, _setTimestampsOnUpdate);
   schema.pre('replaceOne', opts, _setTimestampsOnUpdate);
   schema.pre('update', opts, _setTimestampsOnUpdate);
@@ -96,6 +97,12 @@ module.exports = function setupTimestamps(schema, timestamps) {
     const now = currentTime != null ?
       currentTime() :
       this.model.base.now();
+
+    // Replacing with null update should still trigger timestamps
+    if (this.op === 'findOneAndReplace' && this.getUpdate() == null) {
+      this.setUpdate({});
+    }
+
     applyTimestampsToUpdate(now, createdAt, updatedAt, this.getUpdate(),
       this.options, this.schema);
     applyTimestampsToChildren(now, this.getUpdate(), this.model.schema);
diff --git a/lib/query.js b/lib/query.js
index 3e1943e3cc0..9d3df0931c6 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3331,6 +3331,7 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
   }
 
   this.setOptions(options);
+  this.setOptions({ overwrite: true });
 
   if (!callback) {
     return this;

From 91581d5d94430367ff821b70c78bfb6940ec74c8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Mar 2021 13:14:23 -0500
Subject: [PATCH 1748/2348] test(document): repro #9963

---
 test/document.test.js | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 27b9b83c16f..7f0a225531b 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2519,15 +2519,21 @@ describe('document', function() {
       });
     });
 
-    it('filters out validation on unmodified paths when validateModifiedOnly set (gh-7421)', function(done) {
-      const testSchema = new Schema({ title: { type: String, required: true }, other: String });
+    it('filters out validation on unmodified paths when validateModifiedOnly set (gh-7421) (gh-9963)', function(done) {
+      const testSchema = new Schema({
+        title: { type: String, required: true },
+        other: String,
+        subdocs: [{ name: { type: String, required: true } }]
+      });
 
       const Test = db.model('Test', testSchema);
 
-      Test.create([{}], { validateBeforeSave: false }, function(createError, docs) {
+      const doc = { subdocs: [{ name: null }, { name: 'test' }] };
+      Test.create([doc], { validateBeforeSave: false }, function(createError, docs) {
         assert.equal(createError, null);
         const doc = docs[0];
         doc.other = 'something';
+        doc.subdocs[1].name = 'test2';
         assert.equal(doc.validateSync(undefined, { validateModifiedOnly: true }), null);
         doc.save({ validateModifiedOnly: true }, function(error) {
           assert.equal(error, null);

From 9896ee2e207798618763d6b8bea466798df7378d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Mar 2021 13:17:26 -0500
Subject: [PATCH 1749/2348] fix(document): skip validating array elements that
 aren't modified when `validateModifiedOnly` is set

Fix #9963
---
 lib/document.js             |  6 ++++--
 lib/schema/documentarray.js | 11 ++++++++++-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 042b48ed342..9a9c630e342 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2500,7 +2500,8 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
 
       const doValidateOptions = {
         skipSchemaValidators: skipSchemaValidators[path],
-        path: path
+        path: path,
+        validateModifiedOnly: shouldValidateModifiedOnly
       };
       schemaType.doValidate(val, function(err) {
         if (err && (!schemaType.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
@@ -2626,7 +2627,8 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     const val = _this.$__getValue(path);
     const err = p.doValidateSync(val, _this, {
       skipSchemaValidators: skipSchemaValidators[path],
-      path: path
+      path: path,
+      validateModifiedOnly: shouldValidateModifiedOnly
     });
     if (err && (!p.$isMongooseDocumentArray || err.$isArrayValidatorError)) {
       if (p.$isSingleNested &&
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 1d50941f239..196269437ce 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -251,6 +251,11 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
         doc = array[i] = new Constructor(doc, array, undefined, undefined, i);
       }
 
+      if (options.validateModifiedOnly && !doc.isModified()) {
+        --count || fn(error);
+        continue;
+      }
+
       doc.$__validate(callback);
     }
   }
@@ -267,7 +272,7 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
  * @api private
  */
 
-DocumentArrayPath.prototype.doValidateSync = function(array, scope) {
+DocumentArrayPath.prototype.doValidateSync = function(array, scope, options) {
   const schemaTypeError = SchemaType.prototype.doValidateSync.call(this, array, scope);
   if (schemaTypeError != null) {
     schemaTypeError.$isArrayValidatorError = true;
@@ -299,6 +304,10 @@ DocumentArrayPath.prototype.doValidateSync = function(array, scope) {
       doc = array[i] = new Constructor(doc, array, undefined, undefined, i);
     }
 
+    if (options != null && options.validateModifiedOnly && !doc.isModified()) {
+      continue;
+    }
+
     const subdocValidateError = doc.validateSync();
 
     if (subdocValidateError && resultError == null) {

From bf5a96fdcdf5b74561b815833254df0c9bc00be0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Mar 2021 16:25:09 -0500
Subject: [PATCH 1750/2348] fix(index.d.ts): support setting `type` to an array
 of schemas when using SchemaDefinitionType

Fix #9962
---
 index.d.ts                |  7 ++++++-
 test/typescript/schema.ts | 22 +++++++++++++++++++++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 9f7e1915146..999fc7badb9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1371,8 +1371,13 @@ declare module 'mongoose' {
     currentTime?: () => (Date | number);
   }
 
+  type Unpacked<T> = T extends (infer U)[] ? U : T;
+
   interface SchemaTypeOptions<T> {
-    type?: T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> : T;
+    type?:
+      T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
+      T extends object[] ? T | Schema<Unpacked<T> & Document>[] :
+      T;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 43528dc4611..a5561b49363 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -6,7 +6,23 @@ enum Genre {
   Comedy
 }
 
-const movieSchema: Schema = new Schema({
+interface Actor {
+  name: string,
+  age: number
+}
+const actorSchema =
+  new Schema<Actor & Document, Model<Actor & Document>, Actor>({ name: { type: String }, age: { type: Number } });
+
+interface Movie {
+  title?: string,
+  featuredIn?: string,
+  rating?: number,
+  genre?: string,
+  actionIntensity?: number,
+  actors?: Actor[]
+}
+
+const movieSchema = new Schema<Document<Movie>, Model<Document<Movie>>, Movie>({
   title: String,
   featuredIn: {
     type: String,
@@ -32,6 +48,10 @@ const movieSchema: Schema = new Schema({
       },
       'Action intensity required for action genre'
     ]
+  },
+  actors: {
+    type: [actorSchema],
+    default: undefined
   }
 });
 

From 4f7efb9a7cb44dc30343ccca41639f251e08895d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Mar 2021 22:00:59 -0500
Subject: [PATCH 1751/2348] test: fix tests

---
 lib/schema/documentarray.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 196269437ce..f4cc9907c0c 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -251,7 +251,7 @@ DocumentArrayPath.prototype.doValidate = function(array, fn, scope, options) {
         doc = array[i] = new Constructor(doc, array, undefined, undefined, i);
       }
 
-      if (options.validateModifiedOnly && !doc.isModified()) {
+      if (options != null && options.validateModifiedOnly && !doc.isModified()) {
         --count || fn(error);
         continue;
       }

From 206fc4e35356d819b9c3cc74e594edcc16ec2659 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Mar 2021 22:18:07 -0500
Subject: [PATCH 1752/2348] chore: remove unnecessary &, working on making
 Query inherit from THelpers

---
 index.d.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 9e87d6bc8a7..85e67b6c9fc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1827,7 +1827,7 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false };
 
-  class Query<ResultType, DocType extends Document, THelpers = Record<string, any>> {
+  class Query<ResultType, DocType extends Document, THelpers = any> {
     _mongooseOptions: MongooseQueryOptions;
 
     /** Executes the query */
@@ -1935,9 +1935,9 @@ declare module 'mongoose' {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers> & THelpers;
-    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers> & THelpers;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers> & THelpers;
+    find(callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers>;
+    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
     findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): Query<DocType | null, DocType, THelpers>;

From b24b9176bcce770089c440ce880af286171fec85 Mon Sep 17 00:00:00 2001
From: Emil Janitzek <emil@parakey.co>
Date: Thu, 25 Feb 2021 15:33:41 +0100
Subject: [PATCH 1753/2348] fix: Add generic to plugin schema definition

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 999fc7badb9..e91fa48e48f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1123,7 +1123,7 @@ declare module 'mongoose' {
     pathType(path: string): string;
 
     /** Registers a plugin for this schema. */
-    plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): this;
+    plugin(fn: (schema: Schema<DocType, Model<DocType>, SchemaDefinitionType>, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
     post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;

From a5c7f2261acd8c2d4052b2e863e482ae960b2ebf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 10:45:08 -0500
Subject: [PATCH 1754/2348] fix(index.d.ts): make all query methods instead
 return QueryWithHelpers so they always have helper methods

Fix #9850
---
 index.d.ts | 90 ++++++++++++++++++++++++++++--------------------------
 1 file changed, 46 insertions(+), 44 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 85e67b6c9fc..73994372297 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,8 +99,8 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document, TQueryHelpers = any>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
-  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = any>(
+  export function model<T extends Document, TQueryHelpers = {}>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
+  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
     name: string,
     schema?: Schema<T, U>,
     collection?: string,
@@ -244,7 +244,7 @@ declare module 'mongoose' {
 
     /** Defines or retrieves a model. */
     model<T extends Document>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
-    model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
+    model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = undefined>(
       name: string,
       schema?: Schema<T, U, TQueryHelpers>,
       collection?: string,
@@ -366,7 +366,7 @@ declare module 'mongoose' {
     getIndexes(): any;
   }
 
-  class Document<T = any> {
+  class Document<T = any, TQueryHelpers = {}> {
     constructor(doc?: any);
 
     /** This documents _id. */
@@ -435,11 +435,11 @@ declare module 'mongoose' {
     db: Connection;
 
     /** Removes this document from the db. */
-    delete(options?: QueryOptions): Query<any, this>;
+    delete(options?: QueryOptions): QueryWithHelpers<any, this, TQueryHelpers>;
     delete(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Removes this document from the db. */
-    deleteOne(options?: QueryOptions): Query<any, this>;
+    deleteOne(options?: QueryOptions): QueryWithHelpers<any, this, TQueryHelpers>;
     deleteOne(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Takes a populated field and returns it to its unpopulated state. */
@@ -594,7 +594,7 @@ declare module 'mongoose' {
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document, TQueryHelpers = any> extends NodeJS.EventEmitter {
+  interface Model<T extends Document, TQueryHelpers = undefined> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
@@ -624,12 +624,12 @@ declare module 'mongoose' {
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
+    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
+    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
 
     /** Creates a new document or documents */
     create(doc: T | DocumentDefinition<T>): Promise<T>;
@@ -665,14 +665,14 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): Query<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
@@ -693,10 +693,10 @@ declare module 'mongoose' {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T, TQueryHelpers>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): Query<T | null, T, TQueryHelpers>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
@@ -766,7 +766,7 @@ declare module 'mongoose' {
 
     /** Adds a `$where` clause to this query */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): Query<Array<T>, T, TQueryHelpers>;
+    $where(argument: string | Function): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
 
     /** Registered discriminators for this model. */
     discriminators: { [name: string]: Model<any> } | undefined;
@@ -778,10 +778,10 @@ declare module 'mongoose' {
     discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): Query<Array<any>, T, TQueryHelpers>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, T, TQueryHelpers>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, T, TQueryHelpers>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
 
     /**
      * Returns true if at least one document exists in the database that matches
@@ -791,37 +791,37 @@ declare module 'mongoose' {
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: T[]) => void): Query<Array<T>, T, TQueryHelpers> & TQueryHelpers;
-    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T, TQueryHelpers> & TQueryHelpers;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: T[]) => void): Query<Array<T>, T, TQueryHelpers> & TQueryHelpers;
+    find(callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
-    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T, TQueryHelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T, TQueryHelpers>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): Query<T, T, TQueryHelpers>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): Query<T | null, T, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): Query<Array<T>, T, TQueryHelpers>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
@@ -829,10 +829,10 @@ declare module 'mongoose' {
       callback?: (err: any, res: any) => void
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: CallbackError) => void): Query<any, T, TQueryHelpers>;
+    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, T, TQueryHelpers>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, T, TQueryHelpers>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, T, TQueryHelpers>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -841,18 +841,18 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<mongodb.WriteOpResult['result'], T, TQueryHelpers>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<mongodb.WriteOpResult['result'], T, TQueryHelpers>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<mongodb.UpdateWriteOpResult['result'], T, TQueryHelpers>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<mongodb.UpdateWriteOpResult['result'], T, TQueryHelpers>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<mongodb.UpdateWriteOpResult['result'], T, TQueryHelpers>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<mongodb.UpdateWriteOpResult['result'], T, TQueryHelpers>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
-    where(path: string, val?: any): Query<Array<T>, T, TQueryHelpers>;
-    where(obj: object): Query<Array<T>, T, TQueryHelpers>;
-    where(): Query<Array<T>, T, TQueryHelpers>;
+    where(path: string, val?: any): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    where(obj: object): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    where(): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
   }
 
   interface QueryOptions {
@@ -1052,7 +1052,7 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType, any> = Model<DocType>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1827,7 +1827,9 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false };
 
-  class Query<ResultType, DocType extends Document, THelpers = any> {
+  type QueryWithHelpers<ResultType, DocType extends Document, THelpers = {}> = Query<ResultType, DocType, THelpers> & THelpers;
+
+  class Query<ResultType, DocType extends Document, THelpers = {}> {
     _mongooseOptions: MongooseQueryOptions;
 
     /** Executes the query */

From b8b29f7b638dc16f22eafd578f49c7130756f2d4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 10:53:34 -0500
Subject: [PATCH 1755/2348] test: fix tests re: #9850

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 73994372297..8e441c9cfe0 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -594,7 +594,7 @@ declare module 'mongoose' {
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document, TQueryHelpers = undefined> extends NodeJS.EventEmitter {
+  interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;

From 64739b580a0705b374e096d0e46a015853965849 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 11:02:07 -0500
Subject: [PATCH 1756/2348] fix(index.d.ts): one more test fix re: #9850

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 8e441c9cfe0..34761907dc7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -244,7 +244,7 @@ declare module 'mongoose' {
 
     /** Defines or retrieves a model. */
     model<T extends Document>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
-    model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = undefined>(
+    model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
       name: string,
       schema?: Schema<T, U, TQueryHelpers>,
       collection?: string,

From b23f4f1fc5d39af1fa48c85868f47553b6e70f5b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 11:22:59 -0500
Subject: [PATCH 1757/2348] fix(index.d.ts): allow creating statics without
 passing generics to `Schema` constructor

Fix #9969
---
 index.d.ts                |  2 +-
 test/typescript/models.ts | 17 ++++++++++++++++-
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 999fc7badb9..aa554d5166e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1052,7 +1052,7 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<DocType>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType extends Document = Document, M extends Model<DocType> = Model<any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index c65402c7829..b6917f876e8 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -1,4 +1,4 @@
-import { Schema, Document, Model, connection } from 'mongoose';
+import { Schema, Document, Model, connection, model } from 'mongoose';
 
 function conventionalSyntax(): void {
   interface ITest extends Document {
@@ -49,6 +49,21 @@ function insertManyTest() {
   });
 }
 
+function schemaStaticsWithoutGenerics() {
+  const UserSchema = new Schema({});
+  UserSchema.statics.static1 = function() { return ''; };
+
+  interface IUserDocument extends Document {
+    instanceField: string;
+  }
+  interface IUserModel extends Model<IUserDocument> {
+    static1: () => string;
+  }
+
+  const UserModel: IUserModel = model<IUserDocument, IUserModel>('User', UserSchema);
+  UserModel.static1();
+}
+
 const ExpiresSchema = new Schema({
   ttl: {
     type: Date,

From 0015765c57cd03d7bf834a79b6449ca723d0f64e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 11:59:54 -0500
Subject: [PATCH 1758/2348] fix(index.d.ts): work around #9969 for #9850

---
 index.d.ts                 | 2 +-
 test/typescript/queries.ts | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index ed29d79d375..17c99e0d504 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -99,7 +99,7 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document, TQueryHelpers = {}>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T, TQueryHelpers>;
+  export function model<T extends Document>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
   export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
     name: string,
     schema?: Schema<T, U>,
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index da269afbb75..1d67661cb17 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -17,7 +17,7 @@ interface ITest extends Document {
   tags?: string[];
 }
 
-const Test = model<ITest, QueryHelpers>('Test', schema);
+const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
 
 Test.find().byName('test').orFail().exec().then(console.log);
 

From 0f80ef8191957f81d8753cca746496f5cbd5f4a1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 12:58:37 -0500
Subject: [PATCH 1759/2348] fix(schema): load child class getter for virtuals
 instead of base class when using `loadClass()`

Fix #9975
---
 lib/schema.js       |  8 +++++++-
 test/schema.test.js | 18 ++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 7502b3ba1a7..feb978ccb87 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1900,7 +1900,7 @@ Schema.prototype.loadClass = function(model, virtualsOnly) {
     return this;
   }
 
-  this.loadClass(Object.getPrototypeOf(model));
+  this.loadClass(Object.getPrototypeOf(model), virtualsOnly);
 
   // Add static methods
   if (!virtualsOnly) {
@@ -1927,9 +1927,15 @@ Schema.prototype.loadClass = function(model, virtualsOnly) {
       }
     }
     if (typeof method.get === 'function') {
+      if (this.virtuals[name]) {
+        this.virtuals[name].getters = [];
+      }
       this.virtual(name).get(method.get);
     }
     if (typeof method.set === 'function') {
+      if (this.virtuals[name]) {
+        this.virtuals[name].setters = [];
+      }
       this.virtual(name).set(method.set);
     }
   }, this);
diff --git a/test/schema.test.js b/test/schema.test.js
index 2dbe512425a..ee0d4e8a177 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2566,4 +2566,22 @@ describe('schema', function() {
     assert.equal(schema.path('tags').caster.instance, 'String');
     assert.equal(schema.path('subdocs').casterConstructor.schema.path('name').instance, 'String');
   });
+
+  it('handles loadClass with inheritted getters (gh-9975)', function() {
+    class User {
+      get displayAs() {
+        return null;
+      }
+    }
+
+    class TechnicalUser extends User {
+      get displayAs() {
+        return this.name;
+      }
+    }
+
+    const schema = new Schema({ name: String }).loadClass(TechnicalUser);
+
+    assert.equal(schema.virtuals.displayAs.applyGetters(null, { name: 'test' }), 'test');
+  });
 });

From 6c09419091b3da3f868ca1c345dece068516ffdd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 17:45:06 -0500
Subject: [PATCH 1760/2348] fix(query): handle embedded discriminator paths on
 `$push`

Re: #9977
---
 lib/helpers/query/castUpdate.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index bf60e5d11b7..1ee20fb41f2 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -203,6 +203,13 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
       // watch for embedded doc schemas
       schematype = schema._getSchema(prefix + key);
 
+      if (schematype == null) {
+        const _res = getEmbeddedDiscriminatorPath(schema, obj, filter, prefix + key);
+        if (_res.schematype != null) {
+          schematype = _res.schematype;
+        }
+      }
+
       if (op !== '$setOnInsert' &&
           handleImmutable(schematype, strict, obj, key, prefix + key, context)) {
         continue;

From d2d531b5ae54473e91477a7490645cef2cda8be5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 20:31:30 -0500
Subject: [PATCH 1761/2348] fix(schema): correctly handle trailing array
 filters when looking up schema paths

Fix #9977
---
 .../schema/cleanPositionalOperators.js        |  4 ++--
 .../schema.cleanPositionalOperators.test.js   | 22 +++++++++++++++++++
 2 files changed, 24 insertions(+), 2 deletions(-)
 create mode 100644 test/helpers/schema.cleanPositionalOperators.test.js

diff --git a/lib/helpers/schema/cleanPositionalOperators.js b/lib/helpers/schema/cleanPositionalOperators.js
index b467be44968..905bb78820b 100644
--- a/lib/helpers/schema/cleanPositionalOperators.js
+++ b/lib/helpers/schema/cleanPositionalOperators.js
@@ -7,6 +7,6 @@
 
 module.exports = function cleanPositionalOperators(path) {
   return path.
-    replace(/\.\$(\[[^\]]*\])?\./g, '.0.').
-    replace(/\.(\[[^\]]*\])?\$$/g, '.0');
+    replace(/\.\$(\[[^\]]*\])?(?=\.)/g, '.0').
+    replace(/\.\$(\[[^\]]*\])?$/g, '.0');
 };
\ No newline at end of file
diff --git a/test/helpers/schema.cleanPositionalOperators.test.js b/test/helpers/schema.cleanPositionalOperators.test.js
new file mode 100644
index 00000000000..e22a7d89015
--- /dev/null
+++ b/test/helpers/schema.cleanPositionalOperators.test.js
@@ -0,0 +1,22 @@
+'use strict';
+
+const assert = require('assert');
+const cleanPositionalOperators = require('../../lib/helpers/schema/cleanPositionalOperators');
+
+describe('cleanPositionalOperators', function() {
+  it('replaces trailing array filter', function() {
+    assert.equal(cleanPositionalOperators('questions.$[q]'), 'questions.0');
+  });
+
+  it('replaces trailing $', function() {
+    assert.equal(cleanPositionalOperators('questions.$'), 'questions.0');
+  });
+
+  it('replaces interior array filters', function() {
+    assert.equal(cleanPositionalOperators('questions.$[q].$[r].test'), 'questions.0.0.test');
+  });
+
+  it('replaces interior elemMatch', function() {
+    assert.equal(cleanPositionalOperators('questions.$.$.test'), 'questions.0.0.test');
+  });
+});
\ No newline at end of file

From 561b18c059399be59cdd0a7e29dee21edb886ce2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 3 Mar 2021 20:53:45 -0500
Subject: [PATCH 1762/2348] test(query): add test coverage for #9977

---
 test/query.test.js | 54 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index e7be2f856de..bea3cef1226 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3670,4 +3670,58 @@ describe('Query', function() {
       assert.equal(err.path, '$nor.0');
     });
   });
+
+  it('handles push with array filters (gh-9977)', function() {
+    const questionSchema = new Schema({
+      question_type: { type: String, enum: ['mcq', 'essay'] }
+    }, { discriminatorKey: 'question_type' });
+
+    const quizSchema = new Schema({ quiz_title: String, questions: [questionSchema] });
+    const Quiz = db.model('Test', quizSchema);
+
+    const mcqQuestionSchema = new Schema({
+      text: String,
+      choices: [{ choice_text: String, is_correct: Boolean }]
+    });
+
+    quizSchema.path('questions').discriminator('mcq', mcqQuestionSchema);
+
+    const id1 = new mongoose.Types.ObjectId();
+    const id2 = new mongoose.Types.ObjectId();
+
+    return co(function*() {
+      let quiz = yield Quiz.create({
+        quiz_title: 'quiz',
+        questions: [
+          {
+            _id: id1,
+            question_type: 'mcq',
+            text: 'A or B?',
+            choices: [
+              { choice_text: 'A', is_correct: false },
+              { choice_text: 'B', is_correct: true }
+            ]
+          },
+          {
+            _id: id2,
+            question_type: 'mcq'
+          }
+        ]
+      });
+
+      const filter = { questions: { $elemMatch: { _id: id2, question_type: 'mcq' } } };
+      yield Quiz.updateOne(filter, {
+        $push: {
+          'questions.$.choices': {
+            choice_text: 'choice 1',
+            is_correct: false
+          }
+        }
+      });
+
+      quiz = yield Quiz.findById(quiz);
+      assert.equal(quiz.questions[1].choices.length, 1);
+      assert.equal(quiz.questions[1].choices[0].choice_text, 'choice 1');
+    });
+  });
 });

From a7ceb7ed3b18234a1faf70273faf4864640e00eb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Mar 2021 09:46:36 -0500
Subject: [PATCH 1763/2348] fix(populate): make transform option work
 consistently for both virtual populate and conventional populate

Fix #3775
---
 lib/helpers/populate/assignVals.js |  3 +-
 test/model.populate.test.js        | 70 ++++++++++++++----------------
 2 files changed, 35 insertions(+), 38 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index d5e3ccef04b..2cbe3939cc6 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -209,10 +209,11 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
     const numValues = val.length;
     for (let i = 0; i < numValues; ++i) {
       let subdoc = val[i];
+      const _allIds = Array.isArray(allIds) ? allIds[i] : allIds;
       if (!isPopulatedObject(subdoc) && (!populateOptions.retainNullValues || subdoc != null) && !userSpecifiedTransform) {
         continue;
       } else if (userSpecifiedTransform) {
-        subdoc = transform(isPopulatedObject(subdoc) ? subdoc : null, allIds);
+        subdoc = transform(isPopulatedObject(subdoc) ? subdoc : null, _allIds);
       }
       maybeRemoveId(subdoc, assignmentOpts);
       ret.push(subdoc);
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index da7cd59ea4a..da10db07b6c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10001,17 +10001,19 @@ describe('model: populate:', function() {
       });
 
       let called = [];
+      function transform(doc, id) {
+        called.push({
+          doc: doc,
+          id: id
+        });
+
+        return id;
+      }
 
+      // Populate array of ids
       p = yield Parent.findById(p).populate({
         path: 'children',
-        transform: function(doc, id) {
-          called.push({
-            doc: doc,
-            id: id
-          });
-
-          return id;
-        }
+        transform: transform
       });
 
       assert.equal(called.length, 2);
@@ -10021,37 +10023,25 @@ describe('model: populate:', function() {
       assert.equal(called[1].doc.name, 'Leia');
       assert.equal(called[1].id.toHexString(), children[1]._id.toHexString());
 
+      // Populate single id
       called = [];
       p = yield Parent.findById(p).populate({
         path: 'child',
-        transform: function(doc, id) {
-          called.push({
-            doc: doc,
-            id: id
-          });
-
-          return id;
-        }
+        transform: transform
       });
 
       assert.equal(called.length, 1);
       assert.equal(called[0].doc.name, 'Luke');
       assert.equal(called[0].id.toHexString(), children[0]._id.toHexString());
 
+      // Push a nonexistent id
       const newId = new mongoose.Types.ObjectId();
       yield Parent.updateOne({ _id: p._id }, { $push: { children: newId } });
 
       called = [];
       p = yield Parent.findById(p).populate({
         path: 'children',
-        transform: function(doc, id) {
-          called.push({
-            doc: doc,
-            id: id
-          });
-
-          return id;
-        }
+        transform: transform
       });
       assert.equal(called.length, 3);
       assert.strictEqual(called[2].doc, null);
@@ -10059,18 +10049,24 @@ describe('model: populate:', function() {
 
       assert.equal(p.children[2].toHexString(), newId.toHexString());
 
+      // Populate 2 docs with same id
+      yield Parent.updateOne({ _id: p._id }, { $set: { children: [children[0], children[0]] } });
+      called = [];
+
+      p = yield Parent.findById(p).populate({
+        path: 'children',
+        transform: transform
+      });
+      assert.equal(called.length, 2);
+      assert.equal(called[0].id.toHexString(), children[0]._id.toHexString());
+      assert.equal(called[1].id.toHexString(), children[0]._id.toHexString());
+
+      // Populate single id that points to nonexistent doc
       yield Parent.updateOne({ _id: p._id }, { $set: { child: newId } });
       called = [];
       p = yield Parent.findById(p).populate({
         path: 'child',
-        transform: function(doc, id) {
-          called.push({
-            doc: doc,
-            id: id
-          });
-
-          return id;
-        }
+        transform: transform
       });
 
       assert.equal(called.length, 1);
@@ -10095,9 +10091,9 @@ describe('model: populate:', function() {
 
     return co(function*() {
       let p = yield Parent.create({ name: 'Anakin' });
-      const child = yield Child.create({ name: 'Luke', parentId: p._id });
+      yield Child.create({ name: 'Luke', parentId: p._id });
 
-      let called = [];
+      const called = [];
 
       p = yield Parent.findById(p).populate({
         path: 'child',
@@ -10117,7 +10113,7 @@ describe('model: populate:', function() {
     });
   });
 
-  it('transform with virtual populate, justOne = false (gh-3375) XYZ', function() {
+  it('transform with virtual populate, justOne = false (gh-3375)', function() {
     const parentSchema = new Schema({
       name: String
     });
@@ -10133,12 +10129,12 @@ describe('model: populate:', function() {
 
     return co(function*() {
       let p = yield Parent.create({ name: 'Anakin' });
-      const children = yield Child.create([
+      yield Child.create([
         { name: 'Luke', parentId: p._id },
         { name: 'Leia', parentId: p._id }
       ]);
 
-      let called = [];
+      const called = [];
 
       p = yield Parent.findById(p).populate({
         path: 'children',

From aebbcc1f6f6e42a3f40479a6d0632662fb80227d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Mar 2021 11:24:24 -0500
Subject: [PATCH 1764/2348] feat(query): make `Query#pre()` and `Query#post()`
 public

Fix #9784
---
 lib/document.js    |  4 ++--
 lib/query.js       | 46 ++++++++++++++++++++++++++++++++++++++++------
 test/query.test.js | 17 +++++++++++++++++
 3 files changed, 59 insertions(+), 8 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index c5d4d0b2497..8229d10d2fe 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -779,10 +779,10 @@ Document.prototype.update = function update() {
 
 Document.prototype.updateOne = function updateOne(doc, options, callback) {
   const query = this.constructor.updateOne({ _id: this._id }, doc, options);
-  query._pre(cb => {
+  query.pre(cb => {
     this.constructor._middleware.execPre('updateOne', this, [this], cb);
   });
-  query._post(cb => {
+  query.post(cb => {
     this.constructor._middleware.execPost('updateOne', this, [this], {}, cb);
   });
 
diff --git a/lib/query.js b/lib/query.js
index 0c3ac5a18af..645c31df944 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4470,20 +4470,54 @@ Query.prototype.catch = function(reject) {
   return this.exec().then(null, reject);
 };
 
-/*!
- * ignore
+/**
+ * Add pre [middleware](/docs/middleware.html) to this query instance. Doesn't affect
+ * other queries.
+ *
+ * ####Example:
+ *
+ *     const q1 = Question.find({ answer: 42 });
+ *     q1.pre(function middleware() {
+ *       console.log(this.getFilter());
+ *     });
+ *     await q1.exec(); // Prints "{ answer: 42 }"
+ *
+ *     // Doesn't print anything, because `middleware()` is only
+ *     // registered on `q1`.
+ *     await Question.find({ answer: 42 });
+ *
+ * @param {Function} fn
+ * @return {Promise}
+ * @api public
  */
 
-Query.prototype._pre = function(fn) {
+Query.prototype.pre = function(fn) {
   this._hooks.pre('exec', fn);
   return this;
 };
 
-/*!
- * ignore
+/**
+ * Add post [middleware](/docs/middleware.html) to this query instance. Doesn't affect
+ * other queries.
+ *
+ * ####Example:
+ *
+ *     const q1 = Question.find({ answer: 42 });
+ *     q1.post(function middleware() {
+ *       console.log(this.getFilter());
+ *     });
+ *     await q1.exec(); // Prints "{ answer: 42 }"
+ *
+ *     // Doesn't print anything, because `middleware()` is only
+ *     // registered on `q1`.
+ *     await Question.find({ answer: 42 });
+ *
+ * @param {Function} fn
+ * @return {Promise}
+ * @api public
  */
 
-Query.prototype._post = function(fn) {
+Query.prototype.post = function(fn) {
   this._hooks.post('exec', fn);
   return this;
 };
diff --git a/test/query.test.js b/test/query.test.js
index bea3cef1226..ec3cbe670c9 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3724,4 +3724,21 @@ describe('Query', function() {
       assert.equal(quiz.questions[1].choices[0].choice_text, 'choice 1');
     });
   });
+
+  it('Query#pre() (gh-9784)', function() {
+    const Question = db.model('Test', Schema({ answer: Number }));
+    return co(function*() {
+      const q1 = Question.find({ answer: 42 });
+      const called = [];
+      q1.pre(function middleware() {
+        called.push(this.getFilter());
+      });
+      yield q1.exec();
+      assert.equal(called.length, 1);
+      assert.deepEqual(called[0], { answer: 42 });
+
+      yield Question.find({ answer: 42 });
+      assert.equal(called.length, 1);
+    });
+  });
 });

From 5c5fcbc0ed726f990ac78d5d79d66cb9f343d0a9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Mar 2021 11:53:14 -0500
Subject: [PATCH 1765/2348] feat(connection+index): emit 'model' and
 'deleteModel' events on connections when creating and deleting models

Fix #9983
---
 lib/connection.js       |  2 ++
 lib/index.js            |  2 ++
 test/connection.test.js | 21 +++++++++++++++++++--
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 2f6214b088b..c84c06b7d41 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1309,6 +1309,8 @@ Connection.prototype.deleteModel = function(name) {
     delete this.models[name];
     delete this.collections[collectionName];
     delete this.base.modelSchemas[name];
+
+    this.emit('deleteModel', model);
   } else if (name instanceof RegExp) {
     const pattern = name;
     const names = this.modelNames();
diff --git a/lib/index.js b/lib/index.js
index 1425cfac69a..bc22f820c3d 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -581,6 +581,8 @@ Mongoose.prototype.model = function(name, schema, collection, skipInit) {
     model.init(function $modelInitNoop() {});
   }
 
+  connection.emit('model', model);
+
   if (options.cache === false) {
     return model;
   }
diff --git a/test/connection.test.js b/test/connection.test.js
index 74fa858d4f6..3eab9f19ce9 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1124,16 +1124,22 @@ describe('connections:', function() {
   it('deleteModel()', function() {
     const conn = mongoose.createConnection('mongodb://localhost:27017/gh6813');
 
-    conn.model('gh6813', new Schema({ name: String }));
+    let Model = conn.model('gh6813', new Schema({ name: String }));
+
+    const events = [];
+    conn.on('deleteModel', model => events.push(model));
 
     assert.ok(conn.model('gh6813'));
     conn.deleteModel('gh6813');
 
+    assert.equal(events.length, 1);
+    assert.equal(events[0], Model);
+
     assert.throws(function() {
       conn.model('gh6813');
     }, /Schema hasn't been registered/);
 
-    const Model = conn.model('gh6813', new Schema({ name: String }));
+    Model = conn.model('gh6813', new Schema({ name: String }));
     assert.ok(Model);
     return Model.create({ name: 'test' });
   });
@@ -1242,9 +1248,20 @@ describe('connections:', function() {
   it('allows overwriting models (gh-9406)', function() {
     const m = new mongoose.Mongoose();
 
+    const events = [];
+    m.connection.on('model', model => events.push(model));
+
     const M1 = m.model('Test', Schema({ name: String }), null, { overwriteModels: true });
+    assert.equal(events.length, 1);
+    assert.equal(events[0], M1);
+
     const M2 = m.model('Test', Schema({ name: String }), null, { overwriteModels: true });
+    assert.equal(events.length, 2);
+    assert.equal(events[1], M2);
+
     const M3 = m.connection.model('Test', Schema({ name: String }), null, { overwriteModels: true });
+    assert.equal(events.length, 3);
+    assert.equal(events[2], M3);
 
     assert.ok(M1 !== M2);
     assert.ok(M2 !== M3);

From a57875b6fc7baf9104473d80c8eea463f2bdb344 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 4 Mar 2021 12:28:02 -0500
Subject: [PATCH 1766/2348] feat(index): emit 'createConnection' event when
 user calls `mongoose.createConnection()`

Fix #9985
---
 lib/index.js       | 3 +++
 test/index.test.js | 6 ++++++
 2 files changed, 9 insertions(+)

diff --git a/lib/index.js b/lib/index.js
index bc22f820c3d..386b4d2a60e 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -16,6 +16,7 @@ if (global.MONGOOSE_DRIVER_PATH) {
 }
 
 const Document = require('./document');
+const EventEmitter = require('events').EventEmitter;
 const Schema = require('./schema');
 const SchemaType = require('./schematype');
 const SchemaTypes = require('./schema/index');
@@ -65,6 +66,7 @@ function Mongoose(options) {
   this.connections = [];
   this.models = {};
   this.modelSchemas = {};
+  this.events = new EventEmitter();
   // default global options
   this.options = Object.assign({
     pluralization: true
@@ -280,6 +282,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
     options = null;
   }
   _mongoose.connections.push(conn);
+  _mongoose.events.emit('createConnection', conn);
 
   if (arguments.length > 0) {
     return conn.openUri(uri, options, callback);
diff --git a/test/index.test.js b/test/index.test.js
index 322fa4df39d..f4c178a812a 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -530,8 +530,14 @@ describe('mongoose module:', function() {
           cb();
         });
 
+        const events = [];
+        mong.events.on('createConnection', conn => events.push(conn));
+
         const db2 = mong.createConnection(process.env.MONGOOSE_TEST_URI || uri, options);
 
+        assert.equal(events.length, 1);
+        assert.equal(events[0], db2);
+
         db2.on('open', function() {
           connections++;
           cb();

From 8605e1e985675a703bce97fbe440cd844322d99c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 5 Mar 2021 12:30:15 -0500
Subject: [PATCH 1767/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index b975e44bdba..02a2d3e0fc9 100644
--- a/index.pug
+++ b/index.pug
@@ -346,6 +346,9 @@ html(lang='en')
               <a rel="sponsored" href="https://kajino.com/">
                 <img class="sponsor" src="https://images.opencollective.com/kajino-com/02c99ee/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://www.leoboost.com/buy-instagram-likes">
+                <img class="sponsor" src="https://images.opencollective.com/leo-boost1/f744783/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 5277d2429633fa2e99815e544c4f8b24275aaeba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 5 Mar 2021 12:48:21 -0500
Subject: [PATCH 1768/2348] chore: release 5.11.19

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 6e890ba35d5..562714e7315 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.11.19 / 2021-03-05
+====================
+ * fix(document): skip validating array elements that aren't modified when `validateModifiedOnly` is set #9963
+ * fix(timestamps): apply timestamps on `findOneAndReplace()` #9951
+ * fix(schema): correctly handle trailing array filters when looking up schema paths #9977
+ * fix(schema): load child class getter for virtuals instead of base class when using `loadClass()` #9975
+ * fix(index.d.ts): allow creating statics without passing generics to `Schema` constructor #9969
+ * fix(index.d.ts): add QueryHelpers generic to schema and model, make all query methods instead return QueryWithHelpers #9850
+ * fix(index.d.ts): support setting `type` to an array of schemas when using SchemaDefinitionType #9962
+ * fix(index.d.ts): add generic to plugin schema definition #9968 [emiljanitzek](https://github.com/emiljanitzek)
+ * docs: small typo fix #9964 [KrishnaMoorthy12](https://github.com/KrishnaMoorthy12)
+
 5.11.18 / 2021-02-23
 ====================
  * fix(connection): set connection state to `disconnected` if connecting string failed to parse #9921
diff --git a/package.json b/package.json
index a18c2af0db4..17e9ac6a46a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.18",
+  "version": "5.11.19",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From bdb862fe15b77a4c8441320bfff9473f7423abf3 Mon Sep 17 00:00:00 2001
From: Colin Hill <hillct@gmail.com>
Date: Mon, 8 Mar 2021 15:01:04 -0500
Subject: [PATCH 1769/2348] Listening to events on the DB object is deprecated
 in v3.x and will be unsupported in v4 of the mongodb drivers. Adjusted
 remaining listeneers to use the DB client object, as per the MongoDB Driver
 API docs

---
 lib/connection.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 2f6214b088b..5df98fb1954 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -929,7 +929,7 @@ function _setClient(conn, client, options, dbName) {
         }
       });
 
-      db.on('close', function() {
+      client.on('close', function() {
         const type = get(db, 's.topology.s.description.type', '');
         if (type !== 'ReplicaSetWithPrimary') {
           // Implicitly emits 'disconnected'
@@ -945,7 +945,7 @@ function _setClient(conn, client, options, dbName) {
   });
 
   if (!options.useUnifiedTopology) {
-    db.on('reconnect', function() {
+    client.on('reconnect', function() {
       _handleReconnect();
     });
 
@@ -965,7 +965,7 @@ function _setClient(conn, client, options, dbName) {
     });
   }
   if (!options.useUnifiedTopology) {
-    db.on('close', function() {
+    client.on('close', function() {
       // Implicitly emits 'disconnected'
       conn.readyState = STATES.disconnected;
     });
@@ -984,7 +984,7 @@ function _setClient(conn, client, options, dbName) {
       }
     });
 
-    db.on('timeout', function() {
+    client.on('timeout', function() {
       conn.emit('timeout');
     });
   }

From 6c55b6985ad4758494961917aa620d63c2ef4081 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 9 Mar 2021 19:22:53 -0500
Subject: [PATCH 1770/2348] feat(connection): add `noListener` option to help
 with use cases where you're using `useDb()` on every request

Fix #9961
---
 index.d.ts                                    |  2 +-
 lib/connection.js                             |  5 -----
 lib/drivers/node-mongodb-native/connection.js | 20 +++++++++++++++----
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 40f27813862..87eb76a254e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -314,7 +314,7 @@ declare module 'mongoose' {
     transaction(fn: (session: mongodb.ClientSession) => Promise<any>): Promise<any>;
 
     /** Switches to a different database using the same connection pool. */
-    useDb(name: string, options?: { useCache?: boolean }): Connection;
+    useDb(name: string, options?: { useCache?: boolean, noListener?: boolean }): Connection;
 
     /** The username specified in the URI */
     user: string;
diff --git a/lib/connection.js b/lib/connection.js
index c84c06b7d41..1a7b05f2c83 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -116,11 +116,6 @@ Object.defineProperty(Connection.prototype, 'readyState', {
         db.readyState = val;
       }
 
-      // loop over relatedDbs on this connection and change their state
-      for (const k in this.relatedDbs) {
-        this.relatedDbs[k].readyState = val;
-      }
-
       if (STATES.connected === val) {
         this._hasOpened = true;
       }
diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index 57e7195448a..e032eec1960 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -38,16 +38,20 @@ NativeConnection.prototype.__proto__ = MongooseConnection.prototype;
  * Returns a new connection object, with the new db. If you set the `useCache`
  * option, `useDb()` will cache connections by `name`.
  *
+ * **Note:** Calling `close()` on a `useDb()` connection will close the base connection as well.
+ *
  * @param {String} name The database name
  * @param {Object} [options]
  * @param {Boolean} [options.useCache=false] If true, cache results so calling `useDb()` multiple times with the same name only creates 1 connection object.
+ * @param {Boolean} [options.noListener=false] If true, the new connection object won't listen to any events on the base connection. This is better for memory usage in cases where you're calling `useDb()` for every request.
  * @return {Connection} New Connection Object
  * @api public
  */
 
 NativeConnection.prototype.useDb = function(name, options) {
   // Return immediately if cached
-  if (options && options.useCache && this.relatedDbs[name]) {
+  options = options || {};
+  if (options.useCache && this.relatedDbs[name]) {
     return this.relatedDbs[name];
   }
 
@@ -90,16 +94,24 @@ NativeConnection.prototype.useDb = function(name, options) {
 
   function wireup() {
     newConn.client = _this.client;
-    newConn.db = _this.client.db(name);
+    const _opts = {};
+    if (options.hasOwnProperty('noListener')) {
+      _opts.noListener = options.noListener;
+    }
+    newConn.db = _this.client.db(name, _opts);
     newConn.onOpen();
     // setup the events appropriately
-    listen(newConn);
+    if (options.noListener !== true) {
+      listen(newConn);
+    }
   }
 
   newConn.name = name;
 
   // push onto the otherDbs stack, this is used when state changes
-  this.otherDbs.push(newConn);
+  if (options.noListener !== true) {
+    this.otherDbs.push(newConn);
+  }
   newConn.otherDbs.push(this);
 
   // push onto the relatedDbs cache, this is used when state changes

From 6c429ad83891887750d1250c6e675209d184e2e2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Mar 2021 11:29:49 -0500
Subject: [PATCH 1771/2348] test(query): repro #9973

---
 test/services.query.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/services.query.test.js b/test/services.query.test.js
index a79008893c2..4338992bfb2 100644
--- a/test/services.query.test.js
+++ b/test/services.query.test.js
@@ -78,5 +78,24 @@ describe('Query helpers', function() {
 
       done();
     });
+
+    it('handles paths selected with elemMatch (gh-9973)', function(done) {
+      const schema = new Schema({
+        name: String,
+        arr: [{ el: String }]
+      });
+
+      const q = new Query({});
+      q.schema = schema;
+
+      assert.strictEqual(q._fields, void 0);
+
+      q.select({ 'arr.$': 1 });
+      q.populate('arr.el');
+      selectPopulatedFields(q);
+      assert.deepEqual(q._fields, { 'arr.$': 1 });
+
+      done();
+    });
   });
 });

From 55c8d308048e95eec6cbd1ad20305ed8f88f93ad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Mar 2021 11:30:45 -0500
Subject: [PATCH 1772/2348] fix(query+populate): avoid unnecessarily projecting
 in subpath when populating a path that uses an elemMatch projection

Fix #9973
---
 lib/helpers/query/selectPopulatedFields.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/query/selectPopulatedFields.js b/lib/helpers/query/selectPopulatedFields.js
index 0653f18d71d..0419425d1af 100644
--- a/lib/helpers/query/selectPopulatedFields.js
+++ b/lib/helpers/query/selectPopulatedFields.js
@@ -37,10 +37,10 @@ function isPathInFields(userProvidedFields, path) {
   const len = pieces.length;
   let cur = pieces[0];
   for (let i = 1; i < len; ++i) {
-    if (userProvidedFields[cur] != null) {
+    if (userProvidedFields[cur] != null || userProvidedFields[cur + '.$'] != null) {
       return true;
     }
     cur += '.' + pieces[i];
   }
-  return userProvidedFields[cur] != null;
+  return userProvidedFields[cur] != null || userProvidedFields[cur + '.$'] != null;
 }

From 470bca0c39c1aebc3059809df1e272770250939d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Mar 2021 11:32:39 -0500
Subject: [PATCH 1773/2348] test: move services.query.test.js ->
 helpers/query.test.js re: #9973

---
 test/{services.query.test.js => helpers/query.test.js} | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
 rename test/{services.query.test.js => helpers/query.test.js} (91%)

diff --git a/test/services.query.test.js b/test/helpers/query.test.js
similarity index 91%
rename from test/services.query.test.js
rename to test/helpers/query.test.js
index 4338992bfb2..5fe8e0c4132 100644
--- a/test/services.query.test.js
+++ b/test/helpers/query.test.js
@@ -1,11 +1,11 @@
 'use strict';
 
-require('./common');
+require('../common');
 
-const Query = require('../lib/query');
-const Schema = require('../lib/schema');
+const Query = require('../../lib/query');
+const Schema = require('../../lib/schema');
 const assert = require('assert');
-const selectPopulatedFields = require('../lib/helpers/query/selectPopulatedFields');
+const selectPopulatedFields = require('../../lib/helpers/query/selectPopulatedFields');
 
 describe('Query helpers', function() {
   describe('selectPopulatedFields', function() {

From b5abbe6f40b4eb19ee3e5ae0e58f0ce7859e3fc9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Mar 2021 11:44:05 -0500
Subject: [PATCH 1774/2348] refactor(query): use `isExclusive()` helper for
 checking both document and query projections

Re: #9973
---
 lib/helpers/projection/isExclusive.js      |  4 ++++
 lib/helpers/query/selectPopulatedFields.js |  7 +++++--
 lib/query.js                               | 17 ++---------------
 3 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/lib/helpers/projection/isExclusive.js b/lib/helpers/projection/isExclusive.js
index 8c64bc50fe2..cbf1b78787f 100644
--- a/lib/helpers/projection/isExclusive.js
+++ b/lib/helpers/projection/isExclusive.js
@@ -7,6 +7,10 @@ const isDefiningProjection = require('./isDefiningProjection');
  */
 
 module.exports = function isExclusive(projection) {
+  if (projection == null) {
+    return null;
+  }
+
   const keys = Object.keys(projection);
   let ki = keys.length;
   let exclude = null;
diff --git a/lib/helpers/query/selectPopulatedFields.js b/lib/helpers/query/selectPopulatedFields.js
index 0419425d1af..82f52aa5dd5 100644
--- a/lib/helpers/query/selectPopulatedFields.js
+++ b/lib/helpers/query/selectPopulatedFields.js
@@ -1,5 +1,8 @@
 'use strict';
 
+const isExclusive = require('../projection/isExclusive');
+const isInclusive = require('../projection/isInclusive');
+
 /*!
  * ignore
  */
@@ -10,7 +13,7 @@ module.exports = function selectPopulatedFields(query) {
   if (opts.populate != null) {
     const paths = Object.keys(opts.populate);
     const userProvidedFields = query._userProvidedFields || {};
-    if (query.selectedInclusively()) {
+    if (isInclusive(query._fields)) {
       for (const path of paths) {
         if (!isPathInFields(userProvidedFields, path)) {
           query.select(path);
@@ -18,7 +21,7 @@ module.exports = function selectPopulatedFields(query) {
           delete query._fields[path];
         }
       }
-    } else if (query.selectedExclusively()) {
+    } else if (isExclusive(query._fields)) {
       for (const path of paths) {
         if (userProvidedFields[path] == null) {
           delete query._fields[path];
diff --git a/lib/query.js b/lib/query.js
index 9d3df0931c6..117dddcb893 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -22,6 +22,7 @@ const promiseOrCallback = require('./helpers/promiseOrCallback');
 const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const hasDollarKeys = require('./helpers/query/hasDollarKeys');
 const helpers = require('./queryhelpers');
+const isExclusive = require('./helpers/projection/isExclusive');
 const isInclusive = require('./helpers/projection/isInclusive');
 const mquery = require('mquery');
 const parseProjection = require('./helpers/projection/parseProjection');
@@ -5369,21 +5370,7 @@ Query.prototype.selectedInclusively = function selectedInclusively() {
  */
 
 Query.prototype.selectedExclusively = function selectedExclusively() {
-  if (!this._fields) {
-    return false;
-  }
-
-  const keys = Object.keys(this._fields);
-  for (const key of keys) {
-    if (key === '_id') {
-      continue;
-    }
-    if (this._fields[key] === 0 || this._fields[key] === false) {
-      return true;
-    }
-  }
-
-  return false;
+  return isExclusive(this._fields);
 };
 
 /*!

From c2582d54b4c3bca98cdc1fb60b861ebbe23fd53e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Mar 2021 11:53:58 -0500
Subject: [PATCH 1775/2348] refactor: make `selectPopulatedFields` only take in
 POJOs, rather than whole query object re: #9973

---
 lib/helpers/query/selectPopulatedFields.js | 34 ++++-----
 lib/query.js                               |  2 +-
 test/helpers/query.test.js                 | 80 ++++------------------
 3 files changed, 30 insertions(+), 86 deletions(-)

diff --git a/lib/helpers/query/selectPopulatedFields.js b/lib/helpers/query/selectPopulatedFields.js
index 82f52aa5dd5..92f1d87e04b 100644
--- a/lib/helpers/query/selectPopulatedFields.js
+++ b/lib/helpers/query/selectPopulatedFields.js
@@ -7,25 +7,25 @@ const isInclusive = require('../projection/isInclusive');
  * ignore
  */
 
-module.exports = function selectPopulatedFields(query) {
-  const opts = query._mongooseOptions;
+module.exports = function selectPopulatedFields(fields, userProvidedFields, populateOptions) {
+  if (populateOptions == null) {
+    return;
+  }
 
-  if (opts.populate != null) {
-    const paths = Object.keys(opts.populate);
-    const userProvidedFields = query._userProvidedFields || {};
-    if (isInclusive(query._fields)) {
-      for (const path of paths) {
-        if (!isPathInFields(userProvidedFields, path)) {
-          query.select(path);
-        } else if (userProvidedFields[path] === 0) {
-          delete query._fields[path];
-        }
+  const paths = Object.keys(populateOptions);
+  userProvidedFields = userProvidedFields || {};
+  if (isInclusive(fields)) {
+    for (const path of paths) {
+      if (!isPathInFields(userProvidedFields, path)) {
+        fields[path] = 1;
+      } else if (userProvidedFields[path] === 0) {
+        delete fields[path];
       }
-    } else if (isExclusive(query._fields)) {
-      for (const path of paths) {
-        if (userProvidedFields[path] == null) {
-          delete query._fields[path];
-        }
+    }
+  } else if (isExclusive(fields)) {
+    for (const path of paths) {
+      if (userProvidedFields[path] == null) {
+        delete fields[path];
       }
     }
   }
diff --git a/lib/query.js b/lib/query.js
index 117dddcb893..5b914c31faa 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4854,7 +4854,7 @@ Query.prototype._applyPaths = function applyPaths() {
   }
 
   if (_selectPopulatedPaths) {
-    selectPopulatedFields(this);
+    selectPopulatedFields(this._fields, this._userProvidedFields, this._mongooseOptions.populate);
   }
 };
 
diff --git a/test/helpers/query.test.js b/test/helpers/query.test.js
index 5fe8e0c4132..ad71b4f05a1 100644
--- a/test/helpers/query.test.js
+++ b/test/helpers/query.test.js
@@ -2,98 +2,42 @@
 
 require('../common');
 
-const Query = require('../../lib/query');
-const Schema = require('../../lib/schema');
 const assert = require('assert');
 const selectPopulatedFields = require('../../lib/helpers/query/selectPopulatedFields');
 
 describe('Query helpers', function() {
   describe('selectPopulatedFields', function() {
     it('handles nested populate if parent key is projected in (gh-5669)', function(done) {
-      const schema = new Schema({
-        nested: {
-          key1: String,
-          key2: String
-        }
-      });
+      const fields = { nested: 1 };
+      selectPopulatedFields(fields, { nested: 1 }, { 'nested.key1': true });
 
-      const q = new Query({});
-      q.schema = schema;
-
-      assert.strictEqual(q._fields, void 0);
-
-      q.select('nested');
-      q.populate('nested.key1');
-      assert.deepEqual(q._fields, { nested: 1 });
-
-      selectPopulatedFields(q);
-
-      assert.deepEqual(q._fields, { nested: 1 });
+      assert.deepEqual(fields, { nested: 1 });
 
       done();
     });
 
     it('handles nested populate if parent key is projected out (gh-5669)', function(done) {
-      const schema = new Schema({
-        nested: {
-          key1: String,
-          key2: String
-        }
-      });
-
-      const q = new Query({});
-      q.schema = schema;
-
-      assert.strictEqual(q._fields, void 0);
-
-      q.select('-nested');
-      q.populate('nested.key1');
-      assert.deepEqual(q._fields, { nested: 0 });
-
-      selectPopulatedFields(q);
+      const fields = { nested: 0 };
+      selectPopulatedFields(fields, { nested: 0 }, { 'nested.key1': true });
 
-      assert.deepEqual(q._fields, { nested: 0 });
+      assert.deepEqual(fields, { nested: 0 });
 
       done();
     });
 
     it('handle explicitly excluded paths (gh-7383)', function(done) {
-      const schema = new Schema({
-        name: String,
-        other: String
-      });
+      const fields = { name: 1, other: 0 };
+      selectPopulatedFields(fields, Object.assign({}, fields), { other: 1 });
 
-      const q = new Query({});
-      q.schema = schema;
-
-      assert.strictEqual(q._fields, void 0);
-
-      q.select({ name: 1, other: 0 });
-      q.populate('other');
-      assert.deepEqual(q._fields, { name: 1, other: 0 });
-
-      selectPopulatedFields(q);
-
-      assert.deepEqual(q._fields, { name: 1 });
+      assert.deepEqual(fields, { name: 1 });
 
       done();
     });
 
     it('handles paths selected with elemMatch (gh-9973)', function(done) {
-      const schema = new Schema({
-        name: String,
-        arr: [{ el: String }]
-      });
-
-      const q = new Query({});
-      q.schema = schema;
-
-      assert.strictEqual(q._fields, void 0);
-
-      q.select({ 'arr.$': 1 });
-      q.populate('arr.el');
-      selectPopulatedFields(q);
-      assert.deepEqual(q._fields, { 'arr.$': 1 });
+      const fields = { 'arr.$': 1 };
+      selectPopulatedFields(fields, Object.assign({}, fields), { 'arr.el': 1 });
+      assert.deepEqual(fields, { 'arr.$': 1 });
 
       done();
     });

From 433e6b4092e0c9971b5000209aa2646812e242f8 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 10 Mar 2021 16:05:17 -0500
Subject: [PATCH 1776/2348] fix: only hexadecimal strings allowed if length of
 string is 24

---
 lib/index.js       |  5 ++++-
 test/index.test.js | 21 +++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index 1425cfac69a..e3be1238c7e 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -997,7 +997,10 @@ Mongoose.prototype.isValidObjectId = function(v) {
     v = v.toString();
   }
 
-  if (typeof v === 'string' && (v.length === 12 || v.length === 24)) {
+  if (typeof v === 'string' && v.length === 12) {
+    return true;
+  }
+  if (typeof v === 'string' && v.length === 24 && /^[a-f0-9]*$/.test(v)) {
     return true;
   }
 
diff --git a/test/index.test.js b/test/index.test.js
index 322fa4df39d..a818cd5c5b6 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -812,5 +812,26 @@ describe('mongoose module:', function() {
         assert.ok(!movie.genre);
       });
     });
+    it('should prevent non-hexadecimal strings (gh-9996)', function() {
+      return co(function* () {
+        const m = new mongoose.Mongoose();
+        const db = yield m.connect('mongodb://localhost:27017', {
+          useNewUrlParser: true,
+          useUnigiedTOpology: true
+        });
+        const boardSchema = new m.Schema({
+          name: { type: String, required: true },
+          ownerId: { type: Schema.ObjectId, required: true, ref: 'User' }
+        });
+        const Board = db.model('Board', boardSchema);
+        const badIdString = '6029f05a87016a5662304t6e';
+        yield Board.create({ name: 'Test', ownerId: '123456789012' });
+        const board = yield Board.findOne({ name: 'Test' });
+        if (mongoose.isValidObjectId(badIdString)) {
+          board.ownerId = badIdString;
+        }
+        yield board.save();
+      });
+    });
   });
 });
\ No newline at end of file

From b3eced20865a852868198b1bc935f5d951560d76 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 10 Mar 2021 21:31:54 -0500
Subject: [PATCH 1777/2348] fix(index.d.ts): make `$pull` more permissive to
 allow dotted paths

Fix #9993
---
 index.d.ts                 | 45 +++++++++++++++++++++++++++++++++++++-
 test/typescript/queries.ts | 12 +++++++++-
 2 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 367685660df..f9e4066e44f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2234,7 +2234,50 @@ declare module 'mongoose' {
 
   export type FilterQuery<T> = _FilterQuery<DocumentDefinition<T>>;
 
-  export type UpdateQuery<T> = mongodb.UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
+  type NumericTypes = number | mongodb.Decimal128 | mongodb.Double | mongodb.Int32 | mongodb.Long;
+
+  type KeysOfAType<TSchema, Type> = {
+    [key in keyof TSchema]: NonNullable<TSchema[key]> extends Type ? key : never;
+  }[keyof TSchema];
+
+  type PullOperator<TSchema> = {
+      [key in KeysOfAType<TSchema, ReadonlyArray<any>>]?:
+          | Partial<Unpacked<TSchema[key]>>
+          | mongodb.ObjectQuerySelector<Unpacked<TSchema[key]>>
+          // Doesn't look like TypeScript has good support for creating an
+          // object containing dotted keys:
+          // https://stackoverflow.com/questions/58434389/typescript-deep-keyof-of-a-nested-object
+          | mongodb.QuerySelector<any>
+          | any;
+  };
+
+  /** @see https://docs.mongodb.com/manual/reference/operator/update */
+  type _UpdateQuery<TSchema> = {
+    /** @see https://docs.mongodb.com/manual/reference/operator/update-field/ */
+    $currentDate?: mongodb.OnlyFieldsOfType<TSchema, Date | mongodb.Timestamp, true | { $type: 'date' | 'timestamp' }>;
+    $inc?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined>;
+    $min?: mongodb.MatchKeysAndValues<TSchema>;
+    $max?: mongodb.MatchKeysAndValues<TSchema>;
+    $mul?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined>;
+    $rename?: { [key: string]: string };
+    $set?: mongodb.MatchKeysAndValues<TSchema>;
+    $setOnInsert?: mongodb.MatchKeysAndValues<TSchema>;
+    $unset?: mongodb.OnlyFieldsOfType<TSchema, any, '' | 1 | true>;
+
+    /** @see https://docs.mongodb.com/manual/reference/operator/update-array/ */
+    $addToSet?: mongodb.SetFields<TSchema>;
+    $pop?: mongodb.OnlyFieldsOfType<TSchema, ReadonlyArray<any>, 1 | -1>;
+    $pull?: PullOperator<TSchema>;
+    $push?: mongodb.PushOperator<TSchema>;
+    $pullAll?: mongodb.PullAllOperator<TSchema>;
+
+    /** @see https://docs.mongodb.com/manual/reference/operator/update-bitwise/ */
+    $bit?: {
+        [key: string]: { [key in 'and' | 'or' | 'xor']?: number };
+    };
+  };
+
+  export type UpdateQuery<T> = _UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
 
   type _AllowStringsForIds<T> = {
     [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 1d67661cb17..0a559b7dede 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -4,17 +4,26 @@ interface QueryHelpers {
   byName(name: string): Query<Array<ITest>, ITest, QueryHelpers>;
 }
 
-const schema: Schema<ITest, Model<ITest>> = new Schema({ name: { type: 'String' }, tags: [String] });
+const schema: Schema<ITest, Model<ITest>> = new Schema({
+  name: { type: 'String' },
+  tags: [String],
+  docs: [{ nested: { id: Number } }]
+});
 
 schema.query.byName = function(name: string): Query<Array<ITest>, ITest, QueryHelpers> {
   return this.find({ name });
 };
 
+interface ISubdoc extends Document {
+  id?: number;
+}
+
 interface ITest extends Document {
   name?: string;
   age?: number;
   parent?: Types.ObjectId;
   tags?: string[];
+  docs?: ISubdoc[];
 }
 
 const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
@@ -58,6 +67,7 @@ Test.findOneAndReplace({ name: 'test' }, { _id: new Types.ObjectId(), name: 'tes
 
 Test.findOneAndUpdate({ name: 'test' }, { $addToSet: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
+Test.findOneAndUpdate({ name: 'test' }, { $pull: { docs: { 'nested.id': 1 } } });
 
 const query: Query<ITest | null, ITest> = Test.findOne();
 query instanceof Query;

From ff289eca501457548cccd53816565d5557aef3fc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 11 Mar 2021 09:40:32 -0500
Subject: [PATCH 1778/2348] chore: release 5.11.20

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 562714e7315..d7ce2d8cb54 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.11.20 / 2021-03-11
+====================
+ * fix(query+populate): avoid unnecessarily projecting in subpath when populating a path that uses an elemMatch projection #9973
+ * fix(connection): avoid `db` events deprecation warning with 'close' events #10004 #9930
+ * fix(index.d.ts): make `$pull` more permissive to allow dotted paths #9993
+
 5.11.19 / 2021-03-05
 ====================
  * fix(document): skip validating array elements that aren't modified when `validateModifiedOnly` is set #9963
diff --git a/package.json b/package.json
index 17e9ac6a46a..064840596bc 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.19",
+  "version": "5.11.20",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From ee1d48f510407d3b9df18d6f6d69602f08a5cf07 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 11 Mar 2021 10:32:12 -0500
Subject: [PATCH 1779/2348] made requested changes

---
 lib/index.js       |  8 +++++++-
 test/index.test.js | 25 ++++++-------------------
 2 files changed, 13 insertions(+), 20 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index e3be1238c7e..d9a84a441da 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -989,7 +989,13 @@ Mongoose.prototype.isValidObjectId = function(v) {
     }
     if (v._id.toString instanceof Function) {
       v = v._id.toString();
-      return typeof v === 'string' && (v.length === 12 || v.length === 24);
+      if (typeof v === 'string' && v.length === 12) {
+        return true;
+      }
+      if (typeof v === 'string' && v.length === 24 && /^[a-f0-9]*$/.test(v)) {
+        return true;
+      }
+      return false;
     }
   }
 
diff --git a/test/index.test.js b/test/index.test.js
index a818cd5c5b6..8d24a0757f6 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -813,25 +813,12 @@ describe('mongoose module:', function() {
       });
     });
     it('should prevent non-hexadecimal strings (gh-9996)', function() {
-      return co(function* () {
-        const m = new mongoose.Mongoose();
-        const db = yield m.connect('mongodb://localhost:27017', {
-          useNewUrlParser: true,
-          useUnigiedTOpology: true
-        });
-        const boardSchema = new m.Schema({
-          name: { type: String, required: true },
-          ownerId: { type: Schema.ObjectId, required: true, ref: 'User' }
-        });
-        const Board = db.model('Board', boardSchema);
-        const badIdString = '6029f05a87016a5662304t6e';
-        yield Board.create({ name: 'Test', ownerId: '123456789012' });
-        const board = yield Board.findOne({ name: 'Test' });
-        if (mongoose.isValidObjectId(badIdString)) {
-          board.ownerId = badIdString;
-        }
-        yield board.save();
-      });
+      const badIdString = 'z'.repeat(24);
+      assert.deepStrictEqual(mongoose.isValidObjectId(badIdString),false);
+      const goodIdString = '1'.repeat(24);
+      assert.deepStrictEqual(mongoose.isValidObjectId(goodIdString), true);
+      const goodIdString2 = '1'.repeat(12);
+      assert.deepStrictEqual(mongoose.isValidObjectId(goodIdString2), true);
     });
   });
 });
\ No newline at end of file

From 0377de030f5d1e5e212f592d7074bc2b237e0f47 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 11 Mar 2021 10:33:46 -0500
Subject: [PATCH 1780/2348] linter fix

---
 test/index.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/index.test.js b/test/index.test.js
index 8d24a0757f6..dbf37697553 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -814,7 +814,7 @@ describe('mongoose module:', function() {
     });
     it('should prevent non-hexadecimal strings (gh-9996)', function() {
       const badIdString = 'z'.repeat(24);
-      assert.deepStrictEqual(mongoose.isValidObjectId(badIdString),false);
+      assert.deepStrictEqual(mongoose.isValidObjectId(badIdString), false);
       const goodIdString = '1'.repeat(24);
       assert.deepStrictEqual(mongoose.isValidObjectId(goodIdString), true);
       const goodIdString2 = '1'.repeat(12);

From d7f852fdaedd08f8b22ca4b90c5c678264824a78 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 11 Mar 2021 14:02:00 -0500
Subject: [PATCH 1781/2348] chore: release 5.12.0

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index d7ce2d8cb54..ee0901b7f77 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.12.0 / 2021-03-11
+===================
+ * feat(populate): add `transform` option that Mongoose will call on every populated doc #3775
+ * feat(query): make `Query#pre()` and `Query#post()` public #9784
+ * feat(document): add `Document#getPopulatedDocs()` to return an array of all populated documents in a document #9702 [IslandRhythms](https://github.com/IslandRhythms)
+ * feat(document): add `Document#getAllSubdocs()` to return an array of all single nested and array subdocuments #9764 [IslandRhythms](https://github.com/IslandRhythms)
+ * feat(schema): allow `schema` as a schema path name #8798 [IslandRhythms](https://github.com/IslandRhythms)
+ * feat(QueryCursor): Add batch processing for eachAsync #9902 [khaledosama999](https://github.com/khaledosama999)
+ * feat(connection): add `noListener` option to help with use cases where you're using `useDb()` on every request #9961
+ * feat(index): emit 'createConnection' event when user calls `mongoose.createConnection()` #9985
+ * feat(connection+index): emit 'model' and 'deleteModel' events on connections when creating and deleting models #9983
+ * feat(query): allow passing `explain` option to `Model.exists()` #8098 [IslandRhythms](https://github.com/IslandRhythms)
+
 5.11.20 / 2021-03-11
 ====================
  * fix(query+populate): avoid unnecessarily projecting in subpath when populating a path that uses an elemMatch projection #9973
diff --git a/package.json b/package.json
index 064840596bc..52801b2e9ae 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.11.20",
+  "version": "5.12.0",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From fc8d57e48a236454863d44e707902c6be447dba9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 11 Mar 2021 14:15:49 -0500
Subject: [PATCH 1782/2348] docs(document): clean up jsdoc for
 $getPopulatedDocs()

---
 lib/document.js | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 8229d10d2fe..018abf4badd 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3914,7 +3914,14 @@ Document.prototype.populate = function populate() {
   return this;
 };
 
-/* Returns an array of all populated documents associated with the query. */
+/**
+ * Gets all populated documents associated with this document.
+ *
+ * @api public
+ * @return {Array<Document>} array of populated documents. Empty array if there are no populated documents associated with this document.
+ * @memberOf Document
+ * @instance
+ */
 Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
   const keys = (Object.keys(this.$__.populated));
   let result = [];

From f9e504d1da103ee439b3188ed7e01ee97189ed33 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 11 Mar 2021 14:28:44 -0500
Subject: [PATCH 1783/2348] fix? hooks now return an array only and typescript
 bugs fixed?

It passed all the already failing tests but now introduces 4 failures.
---
 lib/cursor/QueryCursor.js |  5 +++--
 lib/document.js           |  1 -
 test/query.cursor.test.js | 14 ++++++++++++++
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 32a130f7d7d..8233946bb4e 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -480,7 +480,8 @@ function _waitForCursor(ctx, cb) {
  */
 
 function _create(ctx, doc, populatedIds, cb) {
-  const instance = helpers.createModel(ctx.query.model, doc, ctx.query._fields);
+  doc = [doc];
+  const instance = helpers.createModel(ctx.query.model, [doc], ctx.query._fields);
   const opts = populatedIds ?
     { populated: populatedIds } :
     undefined;
@@ -489,7 +490,7 @@ function _create(ctx, doc, populatedIds, cb) {
     if (err) {
       return cb(err);
     }
-    cb(null, instance);
+    cb(null, doc);
   });
 }
 
diff --git a/lib/document.js b/lib/document.js
index 9a9c630e342..7fe8ec87560 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -589,7 +589,6 @@ Document.prototype.$__init = function(doc, opts) {
   this.constructor.emit('init', this);
 
   this.$__._id = this._id;
-
   return this;
 };
 
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 5fde51466cd..7e44529490a 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -711,4 +711,18 @@ describe('QueryCursor', function() {
       assert.deepEqual(arr, ['KICKBOXER', 'IP MAN', 'ENTER THE DRAGON']);
     });
   });
+  it('returns array for schema hooks gh-9982', () => {
+  const testSchema = new mongoose.Schema({ name: String });
+    testSchema.post('find', (result) => {
+      assert.ok(Array.isArray(result));
+    });
+    const Movie = db.model('Movie', testSchema);
+    return co(function*() {
+      yield Movie.deleteMany({});
+      yield Movie.create({ name: 'Daniel' }, { name: 'Val' }, { name: 'Daniel' });
+      yield Movie.find({name: 'Daniel'}).cursor().eachAsync(doc => {
+      assert.ok(Array.isArray(doc));
+    });
+    });
+  });
 });

From 8ba6439d309e7717acd56647fc9fde99f291d8bd Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 11 Mar 2021 14:31:49 -0500
Subject: [PATCH 1784/2348] linter fixes

---
 test/query.cursor.test.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 7e44529490a..90c7d6ff442 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -712,7 +712,7 @@ describe('QueryCursor', function() {
     });
   });
   it('returns array for schema hooks gh-9982', () => {
-  const testSchema = new mongoose.Schema({ name: String });
+    const testSchema = new mongoose.Schema({ name: String });
     testSchema.post('find', (result) => {
       assert.ok(Array.isArray(result));
     });
@@ -720,9 +720,9 @@ describe('QueryCursor', function() {
     return co(function*() {
       yield Movie.deleteMany({});
       yield Movie.create({ name: 'Daniel' }, { name: 'Val' }, { name: 'Daniel' });
-      yield Movie.find({name: 'Daniel'}).cursor().eachAsync(doc => {
-      assert.ok(Array.isArray(doc));
-    });
+      yield Movie.find({ name: 'Daniel' }).cursor().eachAsync(doc => {
+        assert.ok(Array.isArray(doc));
+      });
     });
   });
 });

From cbf5b102de5de8acafe72761dd721f3bd3a4a6ff Mon Sep 17 00:00:00 2001
From: Francesco Virga <francescod.virga@gmail.com>
Date: Sun, 14 Mar 2021 18:24:59 -0400
Subject: [PATCH 1785/2348] fix: query object types on schema

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index e43941e5c40..b123f7bfe96 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1161,7 +1161,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: (this: M, ...args: any[]) => any };
+    query: { [name: string]: <T extends Query<any, DocType, any>>(this: T, ...args: any[]) => T };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;

From 7c621705a5ec043ba46497f22e3f5e3f91f3c9b7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Mar 2021 13:30:47 -0400
Subject: [PATCH 1786/2348] fix(index.d.ts): fix tests

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b123f7bfe96..8c0304f6d8c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1161,7 +1161,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: <T extends Query<any, DocType, any>>(this: T, ...args: any[]) => T };
+    query: { [name: string]: <T extends Query<any, any, any> = Query<any, any, any>>(this: T, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
@@ -2731,4 +2731,4 @@ declare module 'mongoose' {
 
   /* for ts-mongoose */
   class mquery {}
-}
\ No newline at end of file
+}

From 86b45743ff76b2e908a75262da64b9d993b2d09f Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 15 Mar 2021 16:36:26 -0400
Subject: [PATCH 1787/2348] still working

---
 lib/cursor/QueryCursor.js |  3 +--
 test/query.cursor.test.js | 12 ++++++++----
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 8233946bb4e..d92396b2f2f 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -480,7 +480,6 @@ function _waitForCursor(ctx, cb) {
  */
 
 function _create(ctx, doc, populatedIds, cb) {
-  doc = [doc];
   const instance = helpers.createModel(ctx.query.model, [doc], ctx.query._fields);
   const opts = populatedIds ?
     { populated: populatedIds } :
@@ -490,7 +489,7 @@ function _create(ctx, doc, populatedIds, cb) {
     if (err) {
       return cb(err);
     }
-    cb(null, doc);
+    cb(null, instance);
   });
 }
 
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 90c7d6ff442..59788ad02ac 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -714,15 +714,19 @@ describe('QueryCursor', function() {
   it('returns array for schema hooks gh-9982', () => {
     const testSchema = new mongoose.Schema({ name: String });
     testSchema.post('find', (result) => {
-      assert.ok(Array.isArray(result));
+      
+      console.log('result', result);
+      console.log(new Error().stack);
+      //assert.ok(Array.isArray(result));
     });
     const Movie = db.model('Movie', testSchema);
     return co(function*() {
       yield Movie.deleteMany({});
       yield Movie.create({ name: 'Daniel' }, { name: 'Val' }, { name: 'Daniel' });
-      yield Movie.find({ name: 'Daniel' }).cursor().eachAsync(doc => {
-        assert.ok(Array.isArray(doc));
-      });
+     const test = Movie.find({ name: 'Daniel' }).cursor();
+     test.next().then(doc => {
+       console.log('doc', doc);
+     });
     });
   });
 });

From 8b0350b5751d4861caeebb4c524b4276cb6b3dab Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Mar 2021 19:12:26 -0400
Subject: [PATCH 1788/2348] test(populate): repro #10005

---
 test/model.populate.test.js | 40 +++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a3f821c49e7..a5cea0a105c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10160,4 +10160,44 @@ describe('model: populate:', function() {
       assert.equal(called[1].id.toHexString(), p._id.toHexString());
     });
   });
+
+  it('supports populating dotted subpath of a populated doc that has the same id as a populated doc (gh-10005)', function() {
+    const ModelASchema = new mongoose.Schema({
+      _modelB: {
+        type: mongoose.Types.ObjectId,
+        ref: 'Test1'
+      },
+      _rootModel: {
+        type: mongoose.Types.ObjectId,
+        ref: 'Test'
+      }
+    });
+
+    const ModelBSchema = new mongoose.Schema({
+      _rootModel: {
+        type: mongoose.Types.ObjectId,
+        ref: 'Test'
+      }
+    });
+
+    const RootModelSchema = new mongoose.Schema({ name: String });
+
+    return co(function*() {
+      const ModelA = db.model('Test2', ModelASchema);
+      const ModelB = db.model('Test1', ModelBSchema);
+      const RootModel = db.model('Test', RootModelSchema);
+
+      const rootModel = new RootModel({ name: 'my name' });
+      const modelB = new ModelB({ _rootModel: rootModel });
+      const modelA = new ModelA({ _rootModel: rootModel, _modelB: modelB });
+
+      yield Promise.all([rootModel.save(), modelB.save(), modelA.save()]);
+
+      const modelA1 = yield ModelA.findById(modelA._id);
+      yield modelA1.populate('_modelB _rootModel').execPopulate();
+      yield modelA1.populate('_modelB._rootModel').execPopulate();
+
+      assert.equal(modelA1._modelB._rootModel.name, 'my name');
+    });
+  });
 });

From 82a926ad8575a669f805baa647dcafb73ea501d9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Mar 2021 19:13:47 -0400
Subject: [PATCH 1789/2348] fix(populate): support populating dotted subpath of
 a populated doc that has the same id as a populated doc

Fix #10005
---
 lib/helpers/populate/getSchemaTypes.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index 7626e2a4b84..1e89f4b174f 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -169,11 +169,11 @@ module.exports = function getSchemaTypes(schema, doc, path) {
             nestedPath.concat(parts.slice(0, p))
           );
 
-          if (ret) {
+          if (ret != null) {
             ret.$isUnderneathDocArray = ret.$isUnderneathDocArray ||
               !schema.$isSingleNested;
+            return ret;
           }
-          return ret;
         }
       }
       return foundschema;

From fa3d832a1c4f7102450ba119ee375ee59ff365c2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Mar 2021 19:56:50 -0400
Subject: [PATCH 1790/2348] fix(schema): skip `populated()` check when calling
 `applyGetters()` with a POJO for mongoose-lean-getters support

Fix #9896
---
 lib/schema/array.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 1abcdfc4252..c113cb6bec8 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -261,7 +261,7 @@ SchemaArray.prototype.enum = function() {
  */
 
 SchemaArray.prototype.applyGetters = function(value, scope) {
-  if (scope != null && scope.populated(this.path)) {
+  if (scope != null && scope.$__ != null && scope.populated(this.path)) {
     // means the object id was populated
     return value;
   }

From 9fcb2db0a74e7fa39fe6a8f965ac11f4c7574abf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Mar 2021 21:35:31 -0400
Subject: [PATCH 1791/2348] test(query): repro #9977

---
 test/query.test.js | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index ec3cbe670c9..f5659e87a96 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3674,15 +3674,18 @@ describe('Query', function() {
   it('handles push with array filters (gh-9977)', function() {
     const questionSchema = new Schema({
       question_type: { type: String, enum: ['mcq', 'essay'] }
-    }, { discriminatorKey: 'question_type' });
+    }, { discriminatorKey: 'question_type', strict: 'throw' });
 
-    const quizSchema = new Schema({ quiz_title: String, questions: [questionSchema] });
+    const quizSchema = new Schema({
+      quiz_title: String,
+      questions: [questionSchema]
+    }, { strict: 'throw' });
     const Quiz = db.model('Test', quizSchema);
 
     const mcqQuestionSchema = new Schema({
       text: String,
       choices: [{ choice_text: String, is_correct: Boolean }]
-    });
+    }, { strict: 'throw' });
 
     quizSchema.path('questions').discriminator('mcq', mcqQuestionSchema);
 
@@ -3722,6 +3725,19 @@ describe('Query', function() {
       quiz = yield Quiz.findById(quiz);
       assert.equal(quiz.questions[1].choices.length, 1);
       assert.equal(quiz.questions[1].choices[0].choice_text, 'choice 1');
+
+      yield Quiz.updateOne({ questions: { $elemMatch: { _id: id2 } } }, {
+        $push: {
+          'questions.$[q].choices': {
+            choice_text: 'choice 3',
+            is_correct: false
+          }
+        }
+      }, { arrayFilters: [{ 'q.question_type': 'mcq' }] });
+
+      quiz = yield Quiz.findById(quiz);
+      assert.equal(quiz.questions[1].choices.length, 2);
+      assert.equal(quiz.questions[1].choices[1].choice_text, 'choice 3');
     });
   });
 

From fba34578d20842ad454936fa3fa5ede8ab59b902 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 15 Mar 2021 22:02:10 -0400
Subject: [PATCH 1792/2348] fix(query): correctly cast embedded discriminator
 paths when discriminator key is specified in array filter

Fix #9977
---
 lib/helpers/query/castUpdate.js               |  4 ++--
 .../query/getEmbeddedDiscriminatorPath.js     | 18 +++++++++++++-
 lib/helpers/update/castArrayFilters.js        | 21 ++--------------
 .../update/updatedPathsByArrayFilter.js       | 24 +++++++++++++++++++
 lib/query.js                                  |  3 ++-
 5 files changed, 47 insertions(+), 23 deletions(-)
 create mode 100644 lib/helpers/update/updatedPathsByArrayFilter.js

diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 1ee20fb41f2..29b16c9824d 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -204,7 +204,7 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
       schematype = schema._getSchema(prefix + key);
 
       if (schematype == null) {
-        const _res = getEmbeddedDiscriminatorPath(schema, obj, filter, prefix + key);
+        const _res = getEmbeddedDiscriminatorPath(schema, obj, filter, prefix + key, options);
         if (_res.schematype != null) {
           schematype = _res.schematype;
         }
@@ -324,7 +324,7 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
       // If no schema type, check for embedded discriminators because the
       // filter or update may imply an embedded discriminator type. See #8378
       if (schematype == null) {
-        const _res = getEmbeddedDiscriminatorPath(schema, obj, filter, checkPath);
+        const _res = getEmbeddedDiscriminatorPath(schema, obj, filter, checkPath, options);
         if (_res.schematype != null) {
           schematype = _res.schematype;
           pathDetails = _res.type;
diff --git a/lib/helpers/query/getEmbeddedDiscriminatorPath.js b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
index 395ea75c4bf..f4dc839b9c7 100644
--- a/lib/helpers/query/getEmbeddedDiscriminatorPath.js
+++ b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
@@ -3,19 +3,23 @@
 const cleanPositionalOperators = require('../schema/cleanPositionalOperators');
 const get = require('../get');
 const getDiscriminatorByValue = require('../discriminator/getDiscriminatorByValue');
+const updatedPathsByArrayFilter = require('../update/updatedPathsByArrayFilter');
 
 /*!
  * Like `schema.path()`, except with a document, because impossible to
  * determine path type without knowing the embedded discriminator key.
  */
 
-module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, path) {
+module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, path, options) {
   const parts = path.split('.');
   let schematype = null;
   let type = 'adhocOrUndefined';
 
   filter = filter || {};
   update = update || {};
+  const arrayFilters = options != null && Array.isArray(options.arrayFilters) ?
+    options.arrayFilters : [];
+  const updatedPathsByFilter = updatedPathsByArrayFilter(update);
 
   for (let i = 0; i < parts.length; ++i) {
     const subpath = cleanPositionalOperators(parts.slice(0, i + 1).join('.'));
@@ -39,6 +43,7 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
       if (discriminatorFilterPath in filter) {
         discriminatorKey = filter[discriminatorFilterPath];
       }
+
       const wrapperPath = subpath.replace(/\.\d+$/, '');
       if (schematype.$isMongooseDocumentArrayElement &&
           get(filter[wrapperPath], '$elemMatch.' + key) != null) {
@@ -49,6 +54,17 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
         discriminatorKey = update[discriminatorValuePath];
       }
 
+      for (const filterKey of Object.keys(updatedPathsByFilter)) {
+        const schemaKey = updatedPathsByFilter[filterKey] + '.' + key;
+        const arrayFilterKey = filterKey + '.' + key;
+        if (schemaKey === discriminatorFilterPath) {
+          const filter = arrayFilters.find(filter => filter.hasOwnProperty(arrayFilterKey));
+          if (filter != null) {
+            discriminatorKey = filter[arrayFilterKey];
+          }
+        }
+      }
+
       if (discriminatorKey == null) {
         continue;
       }
diff --git a/lib/helpers/update/castArrayFilters.js b/lib/helpers/update/castArrayFilters.js
index fef89346393..a9992f2a507 100644
--- a/lib/helpers/update/castArrayFilters.js
+++ b/lib/helpers/update/castArrayFilters.js
@@ -3,7 +3,7 @@
 const castFilterPath = require('../query/castFilterPath');
 const cleanPositionalOperators = require('../schema/cleanPositionalOperators');
 const getPath = require('../schema/getPath');
-const modifiedPaths = require('./modifiedPaths');
+const updatedPathsByArrayFilter = require('./updatedPathsByArrayFilter');
 
 module.exports = function castArrayFilters(query) {
   const arrayFilters = query.options.arrayFilters;
@@ -15,24 +15,7 @@ module.exports = function castArrayFilters(query) {
   const schema = query.schema;
   const strictQuery = schema.options.strictQuery;
 
-  const updatedPaths = modifiedPaths(update);
-
-  const updatedPathsByFilter = Object.keys(updatedPaths).reduce((cur, path) => {
-    const matches = path.match(/\$\[[^\]]+\]/g);
-    if (matches == null) {
-      return cur;
-    }
-    for (const match of matches) {
-      const firstMatch = path.indexOf(match);
-      if (firstMatch !== path.lastIndexOf(match)) {
-        throw new Error(`Path '${path}' contains the same array filter multiple times`);
-      }
-      cur[match.substring(2, match.length - 1)] = path.
-        substr(0, firstMatch - 1).
-        replace(/\$\[[^\]]+\]/g, '0');
-    }
-    return cur;
-  }, {});
+  const updatedPathsByFilter = updatedPathsByArrayFilter(update);
 
   for (const filter of arrayFilters) {
     if (filter == null) {
diff --git a/lib/helpers/update/updatedPathsByArrayFilter.js b/lib/helpers/update/updatedPathsByArrayFilter.js
new file mode 100644
index 00000000000..7cbae298402
--- /dev/null
+++ b/lib/helpers/update/updatedPathsByArrayFilter.js
@@ -0,0 +1,24 @@
+'use strict';
+
+const modifiedPaths = require('./modifiedPaths');
+
+module.exports = function updatedPathsByArrayFilter(update) {
+  const updatedPaths = modifiedPaths(update);
+
+  return Object.keys(updatedPaths).reduce((cur, path) => {
+    const matches = path.match(/\$\[[^\]]+\]/g);
+    if (matches == null) {
+      return cur;
+    }
+    for (const match of matches) {
+      const firstMatch = path.indexOf(match);
+      if (firstMatch !== path.lastIndexOf(match)) {
+        throw new Error(`Path '${path}' contains the same array filter multiple times`);
+      }
+      cur[match.substring(2, match.length - 1)] = path.
+        substr(0, firstMatch - 1).
+        replace(/\$\[[^\]]+\]/g, '0');
+    }
+    return cur;
+  }, {});
+};
\ No newline at end of file
diff --git a/lib/query.js b/lib/query.js
index ba43a98c912..86e2e627a22 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4586,7 +4586,8 @@ Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
     strict: strict,
     omitUndefined,
     useNestedStrict: useNestedStrict,
-    upsert: upsert
+    upsert: upsert,
+    arrayFilters: this.options.arrayFilters
   }, this, this._conditions);
 };
 

From b98381981983b8fd0f532d6d90b6ed2506401431 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 16 Mar 2021 10:32:51 -0400
Subject: [PATCH 1793/2348] post hook find does now return an array but gh-9435
 and gh-8235 fail

---
 lib/cursor/QueryCursor.js | 6 +++---
 test/query.cursor.test.js | 7 ++-----
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index d92396b2f2f..de38b820fea 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -441,7 +441,7 @@ function _populateBatch() {
 
 function _nextDoc(ctx, doc, pop, callback) {
   if (ctx.query._mongooseOptions.lean) {
-    return ctx.model.hooks.execPost('find', ctx.query, [doc], err => {
+    return ctx.model.hooks.execPost('find', ctx.query, [[doc]], err => {
       if (err != null) {
         return callback(err);
       }
@@ -453,7 +453,7 @@ function _nextDoc(ctx, doc, pop, callback) {
     if (err != null) {
       return callback(err);
     }
-    ctx.model.hooks.execPost('find', ctx.query, [doc], err => {
+    ctx.model.hooks.execPost('find', ctx.query, [[doc]], err => {
       if (err != null) {
         return callback(err);
       }
@@ -480,7 +480,7 @@ function _waitForCursor(ctx, cb) {
  */
 
 function _create(ctx, doc, populatedIds, cb) {
-  const instance = helpers.createModel(ctx.query.model, [doc], ctx.query._fields);
+  const instance = helpers.createModel(ctx.query.model, doc, ctx.query._fields);
   const opts = populatedIds ?
     { populated: populatedIds } :
     undefined;
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 59788ad02ac..7194ead035e 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -714,10 +714,7 @@ describe('QueryCursor', function() {
   it('returns array for schema hooks gh-9982', () => {
     const testSchema = new mongoose.Schema({ name: String });
     testSchema.post('find', (result) => {
-      
-      console.log('result', result);
-      console.log(new Error().stack);
-      //assert.ok(Array.isArray(result));
+      assert.ok(Array.isArray(result));
     });
     const Movie = db.model('Movie', testSchema);
     return co(function*() {
@@ -725,7 +722,7 @@ describe('QueryCursor', function() {
       yield Movie.create({ name: 'Daniel' }, { name: 'Val' }, { name: 'Daniel' });
      const test = Movie.find({ name: 'Daniel' }).cursor();
      test.next().then(doc => {
-       console.log('doc', doc);
+       assert.ok(doc,doc);
      });
     });
   });

From 468ab22f4d903494ff6c7b8fd2c459503762c33b Mon Sep 17 00:00:00 2001
From: "zhou, peng" <zpbrent@gmail.com>
Date: Wed, 17 Mar 2021 19:09:12 +0800
Subject: [PATCH 1794/2348] Update schema.js

---
 lib/schema.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index fa4b2fda528..ad1f89bb10a 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -466,6 +466,11 @@ Schema.prototype.add = function add(obj, prefix) {
   }
 
   prefix = prefix || '';
+  // avoid prototype pollution
+  if (prefix === '__proto__.' || prefix === 'constructor.' || prefix === 'prototype.') {
+        return this;
+  }
+
   const keys = Object.keys(obj);
 
   for (const key of keys) {

From 4d954f3daa789af13b07505902210a550ee118d6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 17 Mar 2021 21:33:49 -0400
Subject: [PATCH 1795/2348] test(index.d.ts): repro #9989

---
 test/typescript/queries.ts | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 0a559b7dede..5fecaca7507 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -31,6 +31,7 @@ const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
 Test.find().byName('test').orFail().exec().then(console.log);
 
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
+Test.findOne({ 'docs.id': 42 }).exec().then(console.log);
 
 // ObjectId casting
 Test.find({ parent: new Types.ObjectId('0'.repeat(24)) });
@@ -74,4 +75,16 @@ query instanceof Query;
 
 // Chaining
 Test.findOne().where({ name: 'test' });
-Test.where().find({ name: 'test' });
\ No newline at end of file
+Test.where().find({ name: 'test' });
+
+// Super generic query
+function testGenericQuery(): void {
+  interface CommonInterface<T> extends Document {
+    something: string;
+    content: T;
+  }
+
+  async function findSomething<T>(model: Model<CommonInterface<T>>): Promise<CommonInterface<T>> {
+    return model.findOne({something: 'test'}).orFail().exec();
+  }
+}
\ No newline at end of file

From 0d0c820fb1f01284a36996138ff84fb5c9051062 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 17 Mar 2021 21:34:13 -0400
Subject: [PATCH 1796/2348] fix(index.d.ts): avoid omitting function property
 keys in LeanDocuments, because TS can't accurately infer what's a function if
 using generic functions

Fix #9989
---
 index.d.ts                       | 19 +++++++------------
 test/typescript/leanDocuments.ts |  6 +++---
 test/typescript/queries.ts       |  2 +-
 3 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 8c0304f6d8c..19dde9b8b11 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1204,8 +1204,8 @@ declare module 'mongoose' {
     ? (SchemaDefinitionWithBuiltInClass<T> | SchemaTypeOptions<T>) :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
-    Schema<T extends Document ? T : Document<any>> |
-    Schema<T extends Document ? T : Document<any>>[] |
+    Schema<any> |
+    Schema<any>[] |
     SchemaTypeOptions<T extends undefined ? any : T>[] |
     Function[] |
     SchemaDefinition<T> |
@@ -1382,7 +1382,8 @@ declare module 'mongoose' {
   interface SchemaTypeOptions<T> {
     type?:
       T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
-      T extends object[] ? T | Schema<Unpacked<T> & Document>[] :
+      T extends Schema<any> ? T :
+      T extends object[] ? Schema<Document<Unpacked<T>>>[] :
       T;
 
     /** Defines a virtual with the given name that gets/sets this path. */
@@ -1845,14 +1846,14 @@ declare module 'mongoose' {
     exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
 
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): Query<Array<DocType>, DocType, THelpers>;
+    $where(argument: string | Function): Query<DocType[], DocType, THelpers>;
 
     /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     all(val: Array<any>): this;
     all(path: string, val: Array<any>): this;
 
     /** Specifies arguments for an `$and` condition. */
-    and(array: Array<FilterQuery<DocType>>): this;
+    and(array: FilterQuery<DocType>[]): this;
 
     /** Specifies the batchSize option. */
     batchSize(val: number): this;
@@ -2290,12 +2291,6 @@ declare module 'mongoose' {
   };
   export type DocumentDefinition<T> = _AllowStringsForIds<LeanDocument<T>>;
 
-  type FunctionPropertyNames<T> = {
-    // The 1 & T[K] check comes from: https://stackoverflow.com/questions/55541275/typescript-check-for-the-any-type
-    // eslint-disable-next-line @typescript-eslint/ban-types
-    [K in keyof T]: 0 extends (1 & T[K]) ? never : (T[K] extends Function ? K : never)
-  }[keyof T];
-
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
   type TreatAsPrimitives = actualPrimitives |
       // eslint-disable-next-line no-undef
@@ -2314,7 +2309,7 @@ declare module 'mongoose' {
     T[K];
   };
 
-  export type LeanDocument<T> = Omit<Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id' | '__v'> | '$isSingleNested'>, FunctionPropertyNames<T>>;
+  export type LeanDocument<T> = Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id' | '__v'> | '$isSingleNested'>;
 
   export type LeanDocumentOrArray<T> = 0 extends (1 & T) ? T :
     T extends unknown[] ? LeanDocument<T[number]>[] :
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 53e72a89bc0..95a61a1c8b2 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -7,11 +7,12 @@ class Subdoc extends Document {
 }
 
 interface ITestBase {
+  _id?: number;
   name?: string;
   mixed?: any;
 }
 
-interface ITest extends ITestBase, Document {
+interface ITest extends ITestBase, Document<number> {
   subdoc?: Subdoc;
   testMethod: () => number;
   id: string;
@@ -32,13 +33,12 @@ void async function main() {
   const pojo = doc.toObject();
   await pojo.save();
 
-  const _doc: LeanDocument<ITest> = await Test.findOne().orFail().lean();
+  const _doc: ITestBase = await Test.findOne().orFail().lean();
   await _doc.save();
 
   _doc.testMethod();
   _doc.name = 'test';
   _doc.mixed = 42;
-  _doc.id = 'test2';
   console.log(_doc._id);
 
   const hydrated = Test.hydrate(_doc);
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 5fecaca7507..4977ec0b1db 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -85,6 +85,6 @@ function testGenericQuery(): void {
   }
 
   async function findSomething<T>(model: Model<CommonInterface<T>>): Promise<CommonInterface<T>> {
-    return model.findOne({something: 'test'}).orFail().exec();
+    return model.findOne({ something: 'test' }).orFail().exec();
   }
 }
\ No newline at end of file

From 5d96508fefac65a72c7556629e388da49f03fefc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 09:39:21 -0400
Subject: [PATCH 1797/2348] test(document): repro #9995

---
 test/document.test.js | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index b00a643f4c3..1f87fe7563e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10169,4 +10169,41 @@ describe('document', function() {
       assert.equal(fromDb.elements[0].subelements[0].text, 'my text');
     });
   });
+
+  it('toObject() uses child schema `flattenMaps` option by default (gh-9995)', function() {
+    const MapSchema = new Schema({
+      value: { type: Number }
+    }, { _id: false });
+
+    const ChildSchema = new Schema({
+      map: { type: Map, of: MapSchema }
+    });
+    ChildSchema.set('toObject', { flattenMaps: true });
+
+    const ParentSchema = new Schema({
+      child: { type: Schema.ObjectId, ref: 'Child' }
+    });
+
+    const ChildModel = db.model('Child', ChildSchema);
+    const ParentModel = db.model('Parent', ParentSchema);
+
+    return co(function*() {
+      const childDocument = new ChildModel({
+        map: { first: { value: 1 }, second: { value: 2 } }
+      });
+      yield childDocument.save();
+
+      const parentDocument = new ParentModel({ child: childDocument });
+      yield parentDocument.save();
+
+      const resultDocument = yield ParentModel.findOne().populate('child').exec();
+
+      let resultObject = resultDocument.toObject();
+      assert.ok(resultObject.child.map);
+      assert.ok(!(resultObject.child.map instanceof Map));
+
+      resultObject = resultDocument.toObject({ flattenMaps: false });
+      assert.ok(resultObject.child.map instanceof Map);
+    });
+  });
 });

From 9176d306a7628fe5d13cd0be001d975c84beeb3e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 09:39:34 -0400
Subject: [PATCH 1798/2348] fix(document): make `toObject()` use child schema
 `flattenMaps` option by default

Fix #9995
---
 lib/document.js | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 018abf4badd..e37b241a124 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3202,10 +3202,6 @@ Document.prototype.$toObject = function(options, json) {
   options = utils.isPOJO(options) ? clone(options) : {};
   options._calledWithOptions = options._calledWithOptions || clone(options);
 
-  if (!('flattenMaps' in options)) {
-    options.flattenMaps = defaultOptions.flattenMaps;
-  }
-
   let _minimize;
   if (options._calledWithOptions.minimize != null) {
     _minimize = options.minimize;
@@ -3215,6 +3211,15 @@ Document.prototype.$toObject = function(options, json) {
     _minimize = schemaOptions.minimize;
   }
 
+  let flattenMaps;
+  if (options._calledWithOptions.flattenMaps != null) {
+    flattenMaps = options.flattenMaps;
+  } else if (defaultOptions.flattenMaps != null) {
+    flattenMaps = defaultOptions.flattenMaps;
+  } else {
+    flattenMaps = schemaOptions.flattenMaps;
+  }
+
   // The original options that will be passed to `clone()`. Important because
   // `clone()` will recursively call `$toObject()` on embedded docs, so we
   // need the original options the user passed in, plus `_isNested` and
@@ -3222,7 +3227,8 @@ Document.prototype.$toObject = function(options, json) {
   const cloneOptions = Object.assign(utils.clone(options), {
     _isNested: true,
     json: json,
-    minimize: _minimize
+    minimize: _minimize,
+    flattenMaps: flattenMaps
   });
 
   if (utils.hasUserDefinedProperty(options, 'getters')) {

From 428586b5366c9d193ec242a184cce0dbf9bce894 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Dias=20Conde=20Azevedo?=
 <joaodiasconde@gmail.com>
Date: Thu, 18 Mar 2021 15:43:48 +0000
Subject: [PATCH 1799/2348] feat: upgrade mongodb dep to 3.5 to eliminate
 inside circular dependency error

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 52801b2e9ae..e99dc6a4b42 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.4",
+    "mongodb": "3.6.5",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.4",

From 96ca70b3e4dc144784edb277a07ddf54103984eb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 12:56:37 -0400
Subject: [PATCH 1800/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 02a2d3e0fc9..2c91f12a52a 100644
--- a/index.pug
+++ b/index.pug
@@ -349,6 +349,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.leoboost.com/buy-instagram-likes">
                 <img class="sponsor" src="https://images.opencollective.com/leo-boost1/f744783/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://poprey.com/">
+                <img class="sponsor" src="https://images.opencollective.com/jean-mir/1bfbe97/avatar/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From c7c8ca553f8ab4bda1178fd672e31887026848e9 Mon Sep 17 00:00:00 2001
From: Shlomi Assaf <shlomiassaf@users.noreply.github.com>
Date: Thu, 18 Mar 2021 19:00:07 +0200
Subject: [PATCH 1801/2348] invalid  cast method for instance method of
 SchemaType

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 19dde9b8b11..22c53d352ba 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2535,8 +2535,8 @@ declare module 'mongoose' {
     /** Attaches a getter for all instances of this schema type. */
     static get(getter: (value: any) => any): void;
 
-    /** Get/set the function used to cast arbitrary values to this type. */
-    cast(caster: (v: any) => any): (v: any) => any;
+    /** Casts a value to it's schema type instance */
+    cast(value: any, doc: Document, init: boolean, prev?: any, options?: any): any;
 
     /** Sets a default value for this SchemaType. */
     default(val: any): any;

From 7b196f77dca3bbda25e6465219b065f1be7195ae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 13:11:14 -0400
Subject: [PATCH 1802/2348] fix(index.d.ts): correct type definition for
 `SchemaType#cast()`

Fix #9980
---
 index.d.ts        |  4 ++--
 lib/schematype.js | 13 +++++++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 19dde9b8b11..949c142b484 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2535,8 +2535,8 @@ declare module 'mongoose' {
     /** Attaches a getter for all instances of this schema type. */
     static get(getter: (value: any) => any): void;
 
-    /** Get/set the function used to cast arbitrary values to this type. */
-    cast(caster: (v: any) => any): (v: any) => any;
+    /** Cast `val` to this schema type. Each class that inherits from schema type should implement this function. */
+    cast(val: any, doc: Document<any>, init: boolean): any;
 
     /** Sets a default value for this SchemaType. */
     default(val: any): any;
diff --git a/lib/schematype.js b/lib/schematype.js
index 973efe9478f..3d667254e08 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -190,6 +190,19 @@ SchemaType.prototype.castFunction = function castFunction(caster) {
   return this._castFunction;
 };
 
+/**
+ * The function that Mongoose calls to cast arbitrary values to this SchemaType.
+ *
+ * @param {Object} value value to cast
+ * @param {Document} doc document that triggers the casting
+ * @param {Boolean} init
+ * @api public
+ */
+
+SchemaType.prototype.cast = function cast() {
+  throw new Error('Base SchemaType class does not implement a `cast()` function');
+};
+
 /**
  * Sets a default option for this schema type.
  *

From 12767f901f21be8fa119374daf571d96d981f0b7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 13:18:13 -0400
Subject: [PATCH 1803/2348] fix(index.d.ts): support calling
 `findByIdAndUpdate()` with filter, update, callback params

Fix #9981
---
 index.d.ts                 | 1 +
 test/typescript/queries.ts | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 949c142b484..824daceaf6c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -810,6 +810,7 @@ declare module 'mongoose' {
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
     findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
     findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
     findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 4977ec0b1db..26427361764 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -70,6 +70,8 @@ Test.findOneAndUpdate({ name: 'test' }, { $addToSet: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $pull: { docs: { 'nested.id': 1 } } });
 
+Test.findByIdAndUpdate({ name: 'test' }, { name: 'test2' }, (err, doc) => console.log(doc));
+
 const query: Query<ITest | null, ITest> = Test.findOne();
 query instanceof Query;
 

From 7edde3f091266a632865f36a3dd6be905ac87d30 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 13:36:50 -0400
Subject: [PATCH 1804/2348] fix(index.d.ts): make SchemaTypeOptions a class,
 add missing `SchemaType#OptionsConstructor`

Fix #10001
---
 index.d.ts        | 5 ++++-
 lib/schematype.js | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 824daceaf6c..f0d5dd3b50b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1380,7 +1380,7 @@ declare module 'mongoose' {
 
   type Unpacked<T> = T extends (infer U)[] ? U : T;
 
-  interface SchemaTypeOptions<T> {
+  export class SchemaTypeOptions<T> {
     type?:
       T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema<any> ? T :
@@ -2536,6 +2536,9 @@ declare module 'mongoose' {
     /** Attaches a getter for all instances of this schema type. */
     static get(getter: (value: any) => any): void;
 
+    /** The class that Mongoose uses internally to instantiate this SchemaType's `options` property. */
+    OptionsConstructor: typeof SchemaTypeOptions;
+
     /** Cast `val` to this schema type. Each class that inherits from schema type should implement this function. */
     cast(val: any, doc: Document<any>, init: boolean): any;
 
diff --git a/lib/schematype.js b/lib/schematype.js
index 3d667254e08..318a8399271 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -119,7 +119,7 @@ function SchemaType(path, options, instance) {
 }
 
 /*!
- * ignore
+ * The class that Mongoose uses internally to instantiate this SchemaType's `options` property.
  */
 
 SchemaType.prototype.OptionsConstructor = SchemaTypeOptions;

From 9cf48f50d36791f43b517030c5c87a89964bcf75 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 14:21:05 -0400
Subject: [PATCH 1805/2348] chore: release 5.12.1

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index ee0901b7f77..1012951d428 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.12.1 / 2021-03-18
+===================
+ * fix: update mongodb -> 3.6.5 to fix circular dependency warning #9900
+ * fix(document): make `toObject()` use child schema `flattenMaps` option by default #9995
+ * fix(ObjectId): make `isValidObjectId()` check that length 24 strings are hex chars only #10010 #9996 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(query): correctly cast embedded discriminator paths when discriminator key is specified in array filter #9977
+ * fix(schema): skip `populated()` check when calling `applyGetters()` with a POJO for mongoose-lean-getters support #9986
+ * fix(populate): support populating dotted subpath of a populated doc that has the same id as a populated doc #10005
+ * fix(index.d.ts): correct `this` for query helpers #10028 [francescov1](https://github.com/francescov1)
+ * fix(index.d.ts): avoid omitting function property keys in LeanDocuments, because TS can't accurately infer what's a function if using generic functions #9989
+ * fix(index.d.ts): correct type definition for `SchemaType#cast()` #10039 #9980
+ * fix(index.d.ts): make SchemaTypeOptions a class, add missing `SchemaType#OptionsConstructor` #10001
+ * fix(index.d.ts): support calling `findByIdAndUpdate()` with filter, update, callback params #9981
+
 5.12.0 / 2021-03-11
 ===================
  * feat(populate): add `transform` option that Mongoose will call on every populated doc #3775
diff --git a/package.json b/package.json
index 52801b2e9ae..aef90bcfade 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.0",
+  "version": "5.12.1",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 61d313b3c7dbbb5744d0f465d22569483551060a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 18 Mar 2021 14:39:23 -0400
Subject: [PATCH 1806/2348] chore: update opencollective sponsor logo

---
 docs/images/logo-poprey-com-white-100.png | Bin 0 -> 21835 bytes
 index.pug                                 |   2 +-
 2 files changed, 1 insertion(+), 1 deletion(-)
 create mode 100644 docs/images/logo-poprey-com-white-100.png

diff --git a/docs/images/logo-poprey-com-white-100.png b/docs/images/logo-poprey-com-white-100.png
new file mode 100644
index 0000000000000000000000000000000000000000..c4ab421aca1a81b257562c1cb8555b3bfcef6651
GIT binary patch
literal 21835
zcmeI42T+qs_wa)hse%X!NC_Y+C6E9CLhrpd0YL~!fY1UY^eR#mM5Krc8l(s!RhkM2
zDou(af}j*psx%Q40|@vJdcAsc@6EjPeeXBl{Ab8a^5pE<b9VQ)XV304nJ4E=jdhsl
zx#$4^0F$1sraAG7+<DW|5I=p!FIf^VbUwPaSO9?Gz|NZjka>**08qGvwzR?77#YeV
zFka$tB*qyf9^~aitPKDtss#DK5gsTU&>7{5_Er*Ds&5hiqLE4hC!j`PBOeWv8(KHS
z4`mTzY>5c*K){d!D$4YVLGnZgUML(K806*Yjg=2l68P>{p7?#ISV92!y$a4lNkDC<
zL7<J1DNqCBhXO*yWk3jslpIhNCJuqZ<RqoVfRbQ{j06}a0g(oQA@X3DJQxD}<0YU>
zPyD9nhjfuQ*VO)_IijQ_;D*Eb$V*5B1_p`;N{M6qTqPhd7)$~zDIqBdBGv$5gS~O^
zAdoj!@Q0J1el$^7gdf@mhsJmVcl^SgG5$Cu0fC){{(Sv0E-#-y8}i2f!H!5#A_(py
z0TBmF{ELy15qUE&uYa_};<N&YJ^5o~|JWebGS~+tVUEIL{QVFptpJoaPVk>Pfkgc2
z$H(8#^E)3TLIUN9@*<jGiJgc1V;6kfFgOg>4f8MK{!{(0qsO6Leof9_hOndgS2I))
z`d`d;G(XI~hr*8;QY6NoyoMhNj>Gs_VlbY{KcdX^XYYX;8aq)X3p{=T?Ty3)VuckY
zNKJmt_b+cKO*jsvED4r`fWVR<Nl8nHjJ&j@yrirsSW+Gg{>{mcnj}7qh_R1^<KVw}
zkpe;FcD#V0@=&?oz5JyvsUHjy?GpSSdHGfIuRe^7<n_F<IJh?grKhP(9J@Fgjg*&^
zK|$msU1ULE7)%<3l#zyk;IdFC2nlzFpx|=Ok|-JE_d)*E{BN!`F$n*iKq9*SvG9=?
z1kwGU;UN!}azQ{5&Jd8CtP2qV1mz5ZIlG`haAyP@28AJ|Wl>T;8~V-J-x@OULlg57
z-1E0OJ7Yl-8-t^yr4evA3WSo8b^*a8r4b-GX*pStEJO~BbOy_~Nd6kjKe+i@Q@Us@
zF`9yZi!x%Yea}1=DBr)9{#1CPzh@91xE~g^voMteey+?vQ_i0mWyj|G0+)v)c5;t0
zVkdl2MBINV{nf2ME&nh>|9v|DGXy{U|7QO0Z3McZyvc?C4_Du7{ksz^#swD$_d}_<
z5+me4S(!h){?&}sy`scUuJ%O#KbQzCJmCLs8jvuQtP2V*1wuif(jXUEX(R{^1H(ab
zGANh~5+W-l<AVA*&Hu}%;a3zR+~D4>D5SE)&yoEs_}?^h|5-l#KU+ZmnEC(zEujC}
z%>7u2f6a+MQ~BR>s3H;}?}G93g5#9YUT{~GgpaqYqQtMlU(urYYxmH=cw+pFFi4a#
zag+F`;@_-xjurC6{7%d@@b7sQqA2mVGSd1sJ9*mE|9gE|Nigvx0onQd!}NDGsi`e_
z)8EykroSw$ywNyi$v;{nDgMoB=j<c@9fk$*n2u7GfkLIAiV~#7q!y;=Ae5(#CYrcI
zV|R8M;?VvuBGvq(rR~33{-*iE@<%ZIcBKBEpMR7R5A4Ky1&Kdz7XFsH|J>pJn_qqn
z>A&ff#Mf>kBtXcEyST{nA<^#QA^}2P+{Hzn4~cdc7YPvZ;w~=od`PsrxJZDI7k6=y
z=R>01#YF;yyts>tJRcJ6E-n%v<i%ZF<oS?jcX5#bAusOYBF~3JyNini2zhZA7kNG;
z+Fe{EK*)=`xXAM%(eC0R0YYBf#YLVEiFOwk2@vw)E-vzXNVL1SNPv(RcX5&DL!#Zq
zMFNDpxQmNC9}?{@E)pQ*#a&$F`H*OLaghKaFYe+Z&xb_2i;DyZd2tsPc|IiCU0ftU
z$cwwU$nzo5?&2Z=LSEd(MV=3db{7{35c1+KF7kXxw7a-SfRGo-;-dfc_$|tt_{?n}
z@!?uyk7G;32Xlc4U2`J<AVdfNh&lrRtbZe3-va>Vv;Ycr8vsE5G5~N0Gib+m5dh%i
z(bH733>sRv9(;}arT<bB!P+WtRpzUB5>2VDIxB0USyTlb)vKemj~M9MuE@Qq41LGh
zeu3_Bo6Npo<DfP^M0=0im5+2ikPEh6;4FaPL+9Sk^R=%B@%Y)Ay4xSZBR`*iexuYi
z-!^9Ey%eaZxV~U+du{~#Z0TBP*>gJ##oTGdD#`1tfV!9gd8QcGc7(RB_8yI@2`~bw
zyT>_z+vPkhOo2wqz=h%}HPZU$XK?)4V1ZNBGa}cjbwu#46$%C-_`OW;SQBrzf!|dE
z9-TeMo?aDYNDm0s8Z2XbP;b#PEQL$jRC<o*zw{)nXXC~rdi`8>iq83F%V%^JO>+7#
z8)#n|!RHRP(8eTP<vZ(ES|3$+H2}_|5Qlyvt?G(Rb;zQ5A10-zJoD~87eAGG^njDi
z9x1mdnlY<;7ns!nTvMmv>OiD<lU(OxDUqx7)iJTImSBw5Yr~ejP;H7-Uccbwrr}r1
z_9`dwb1pYPiEzDzv!{8WDQ&bxK+V&q<o2}RSbfj1*4WmuF&XF3(2$#}-2DPuY!eZ|
zw6u{1OMe;bLcy8Gq!1sxa;*OKrrV*?lW_o};P5NDMX}~wrD~$#o))KBXendZh~_l)
zertH=4=d)@_BLI0^M}BZM(cbsK!>Noyj$B@4Qq)qG(%NXo_fLIv{G(2!os_O+`QZu
z3tD<aSs%bEo5k6&>LsTfd!`~E#H<&0eX9WI9kb_Me`6f6b;cood|wW0nyFY6nl8-o
z3_h1(Kk%liuu;G(A%z8J9nkh#=Fzf-Wj6iW(Mw^fwJO71$tq1(GfvRlx_XG8Lq=`B
zcQ#_9;jmedFIG9cRG91XW#3UR51Vk?ErkOtQy$wBZ6|`)90Q%>7~L~-*YKIu=vf=j
zB+iSU@7~ngCvU%fRmh&uQ@H;;#}c<{2qAxcyHI9%Wn!_vUq`rzetha>_rB+QQa?N4
zKYWocEGeC~2*ktKwIf$3Uf;Qst)Q|hpj4k`*^}sG!#d?*OqCL+x}JIZ3uDfeR@Wu@
zG^w&H3Pn+dB6mM_p1D4PTRy<JI(f^{GMeN5qXSy$<!Y)=^~|aV!X`}c)3ezhlpsZE
zMon%r^L!zhE0S3&aV(8_#@)zeT1r!MuRQ9JfKe%0%4hY{`5nET9dff(gbx!1#SsR!
zsEeKV;hPQeccch=HXCvqj%s>oq%-k_r|Lw$3UhYT?J}SoSwAFUZo!#TDHD_RDOl$$
zU~pNuxLS=N;$x9fKUB;1!S-5RYx~Pvh2z2AiUbHN56s;-;qCO%0#0={MiF(k@iWdY
z2bEY&6Y@;d@+`Y!ocWlnp99}qRnvVW>u6&#`uKhK=SuJJZ&IEc*)r4R$J_lad(Yfg
z0Ur)#yI!K>4o=QmX0RVH)7AyjQbp79(?8^%B5+XX-O^+|`=mEM(*CU*bq2_77}A|u
zb$hL??~q{r72BwhCOAXj=x5er61TN8TgTqsl9A&~)=WM#5o9?Kd$qnHrZWy4(5<QO
zOJz#sW;CET?h&hKk4odX8X%cqnQdZHrSa{JqBS7*<<UoHxqGiI8zG)5jEAi)S$~`v
zQ}UVyRL;CqYYf^DY!Nw=J{b3LWc-6Z*B)VNrBdM+&B4YGD)2Ao=V6PLAzUWHtrZCb
zSlu`#HK6L%qqqBOG=nq4v=5BUyx90EHq2*GxjHCZ!eWVM12Emzt#ZARYAIk6sFQj!
z5=&PsUX~T1+R)(KeAA?IG4|9n2qZdmmO=R9o-dw<^WD9#sB8@t*>85l9!NY?-7`=+
z?86=ZHU-d2oy0~HV_+n3iKda^B%kq0V&wZ=%w3I9^TYfJgKS+HxJCWm3c0qsc*kTE
z-+@-Yh12i)h-*XC#Q#NgK4XtCD<eNk9iVN6!F_$YZ~hn~O%xlesGE}=tEf**_6^NU
z)~QE6$p&9NV64}JjlcSwKa6*1N$Ap_9eQ^o%mHUqm}Su~aejGvnj&JoN1<S_OP{%J
z#AjMi4xMd-0*v)(q2u_4KqvRgeWk>%k3X1!zh0?m>mwuvTe61^XLh(?b^2MDVg!!9
zV@<Pf6Xfhk;}Opfo6n$vL`T<`V`iql#<|%Xq{>OmY|Lkye8GFax_vQABJVat63zrG
zkefWmx0LH@k_j^~NTAe+LemE{?RR}W<gOe@fW=eg`F{m4k2S^eG|eAXSwLK2_0^2D
z&P$Kyy`H8`6PZ3RxKUby01E6x2t%1Wa{d0LBOBZsLsFk*6fDJQeMXylgkEMBt}k=1
zibfy5c_A~~tg-DvW{X0lVwjE;U%l6AzlW~)ly5U<vSfc&Ude!XXR)N1UW3vZ3AVdU
zpFf=0B!qQN#NYLvRKbjCN-jAW9MIroOwr1_Fu4G{qpjK}`0X+Wts$c)d_OHmP~+oe
zMMdd=hvVb(nQJYw)<DDeo_hQjyJ13_jyiECzqu*ww^GkndmDQDRy^o+_AwU8wJ!w*
z!o^jE)*ASYSzh_TeHQg#Yc>w`sI1j<$11~C6kK_!v>T+J9#RfdX$to~#*p_?tXNbh
z$IMQu{WvP}YDbDd?Uwebyp>q`^sr~gu6LvbR9R+d772?|m!4yGxlf26ezg+DCp#7?
zzMAN~6G!(!UAa=7_ZG56){>iM-==rMXf61ljlEm~><4);`#!zD{?z^fe5&95N!)7F
z)atR2D^=C`$7xQ`>f)wvxiMmg4KB0N^1Mw7`Z!B?)2xyF;L&W2(W_dmH=oW17TQ)+
zCSbnJ=`-d9Eopfqtw8a`PmX+Ac-`BBO|Gt(efI#jDs;udK~3!7k<0$C-#{PUwt{Xh
zjoHT(hJ_GZZe<=&w@WxI9zx#)?R>nBeR3bhHh0#d5KbTRC7-w}rZbt83bIKRYHI{E
zKJR&UXhXQ1nVkpV4!qut?WjMLL`}IC8R#{g(q3CxP>`bf9JmxhOVN3PR>M^4?&KB4
z%UXrj*bbeHJAt7pDjOSEMW3Z&=?(VuORvSeZXvto!$+`PGRj{u#d=J2j5w5SkUMN9
z+=o}CaSAHp2k$&HHMz;H&&SI)<<U8>QN0-vH5k#?IwX3yFm7>l1u0QviPsIj@t&<@
z1#11oX?ds<vgCR|oUq-MD9v$GQ(dira@vFcNaqRUi)X(43C4ETt%H$Yl(*;jdR$E!
zk}V&%)*8(<@5eW|^3|W>I%4O|fAe8Su$X*Jstr(c*y-?@XTVxGAD)imYHc)}^7%qo
zPNe&L!a_xtD08iaxp|mY9Lw7&wy7F8aZ|hit6fex_+^pnMoukb`=^4Kds_=}4EHt=
zOU@@6_8yxtGeb$G`@CA~+NW-IpgA@FK=AFE*sFb(376x_EcY&t0M!J8H1}Ann_8nj
z%?Ua%5@2b}y2D@KUmE0fZLd3|6Chl)(^%e{P&E;*HfuWXv60wh0TytZ!**VHk{?t*
z3H%^4x5syaAdc$Y<f5swpcU>_C469OEKZ37Uj9<#No!sO)KuP^f$qID2TT!l>%65C
z2nHs+u*<4l)L00CDX*_z{E%@3Uks*X?RlxyjPDW7or=Bv8NzkhFXhSO8y7T2O4>`a
zgVP5_eLHjc&#Rs;yIg5Hf4G!x1)p5vH1#_E+38`kMA2;=d*GW5X{bIN=u_pcVo+*z
zn!Of5!%MHhrTeb$>YOI<coj3oB1Y^Zju`t@(<>Vt)X2f52`W#lJ+6l14u71`KI_1n
z%%4hlY{MLvJEgw9s=b?N=e#E9Y8ngPzc)F1YdCSUyxg&~#?dzP3ARK&QaokYE9}Hl
zQ^^)VNc)?T{0NstW>9CI;L8gKqb2JZ+q-xsSw)%Eg$|y?FHEg8*`0@Xc2FG2`uu9!
zkS~YTW2BW{J<2?uWBuIp{`?zdx6}Ji#dj7w8Ga^Ok+0^_1328c0ZcS0hA&Pr?334;
z$fb7|$&<UPsD5^fZHr^@qt_WPJq8m7`Lsn^>6?!vxyLvu6U;MByPd}l)3J`iL}ucS
zwZ|O^@nc+_u88&<5@n(YyZO;{4gdJ?r-`(uGezZMLQx$Ef~V3X!9c`Q07bE~KAwi=
zN)k3?L_beiaQX<y@^ca~>QrZ+bTaW?IUka%khoMdafv4jXQqFk_2?y^eR)XgQVz^=
zzBYoEQuv5NkueRH&a>(*YjU)}k+rfOr%)F^3NyU2?+_EM?mJVn!1veg&aYDs%RHLt
zN<SJ0ey>|2^}dDf>fRRNTveAgg{ri@y7KSFzaG=pO6I5LanRr>c$;8SB0uR$6Dq|>
zaHWgs_6-f*8}0ldyK$T<N!{BKpih@dIpI+$?Va~Qp7-oS#w*D;?s{Aapz&1*>)&3l
zf5@OPNoT7jGqS8~eQng|iN(UGvMNTPb!6xTonzZABQ^EVO3Ir#kIR6?*r=mYiszz;
zCpmEGRfr>J!DMc6hTjU_PG4VxR+vSdc#KzYHnTfCK0*+4?wA{D#!mz?FSf02-p%Ob
zp*$W3ey-kkX-*v|T-Bw^39A$iWQ8K-lBHc~fEivN?<<JoKN12T475vZ&s&K!!`rON
zap|*NCnETb)%I8Bu1$C{$d>i8$2n=Q)wds?jcGnn79JJWnO7|t)^Fb)<Eel9E$iN=
z4<{+i&Dq8JXYmguU!}eKbYlC^$v5wjaE;ZNr1f6U1R=wr_~DKx?>e$71*T4`BTH9(
zEj|hNC8))_@_9~|os_98yq_$@RO94U?P$0)+v1s^`u6O|Bn7KDlM{y&C2gtnb&$rS
z1+TX5!b~?y?(>l5WuHo3VsEBrPQG6AVE~mA;8_$0p#yJ4V^z-izvW6wPkmAO@q4c{
zb<IpKqG?+6LPva_ZY_9z$Pr-)pO21Fy-zP&xa`MUw&J@?$8i)p*Gcz^Cb&HtM?HA^
z;)~LfL_=QSP3WWjyz^_t>-R7=s^T9~IQ=@P8z{q)dIt`(4%Z&1i=ovLW7HU5k9{0p
zbj7P?fY!ovlq1Vfbs+^B9m^}w*O{PuODx$;C*$_e6OI{^rbR2^q?NEYnS%w|dot8o
z<)BFWQ`WW)XX9ES*U}XtqL(Wo9=1H-zR9k9+lhJKnwdVks%gkjhC^tX0NXzEVUFvH
zswFp&>(o%B1+SmLa*o^@9S_JIPgfRgO|3r-3T=tG;w3CJo8G)qvuZhDA^-#=b?NJ*
zTC_U4<s_vZ$zI-fTSOLg&ZX|mQ+06-4xrJO@=8{=42knu0}v{-Y|k76S3A@DdlYCn
zSR7By6I4SkI;iv!y<RG%_-u=fcuuvX<#E-lHts}zYGp137gk2j<2NCOYT{E;BbVE`
z2hA%U+qD3WG8h+eH3cLQ7*-PzCH5z}oLmcn%#A(v@Sn-Si-m{wA@*JOjX0ntCaJd<
z!KJ!?&kBt19CA6+uUgzq>t26uIY^_YO!^%wgCjdb*%9T7@Yy*#W90_{D-;mJj@$k<
zNS^YF3%NE-bR0)QunWQdKHYa-&OrT!gp3w=I38xw3_h)7tP6e7ZOc8i$qY^9>YS+0
z)IF!y^M-Bf0cSLS)mn9K6u)dU--AH@cQ#Hd6cjcO8u4|(5Y|!S(>`JwXg1HtTFgRd
z+*^r8+&=My3)@s`UEK3s24)-=@9Kf2>%N%sQF5ee3h0>6+}~(Jr4O9U-|N6=0A%X8
zkaT7;oX-qtdnY~m^F@ub0M`<a%;!)e+KWTfX4a*}La_JeJ$zkD1fCc$`#)cI@$0_R
zHwayhEk9+5t-Jh;*ic^!_y~P0N}mzU&1x@Yy4HOUGsI$(p{9txDU|ZIna{CPXi&Dd
zM$|}r%1lbdum{iBqxf8{e;?aoBQ5{?!}^ue*R%)hpUd&99#z!27V3ZC@RCQXUNDuQ
zw%J2XQL%s}j>(y^k+!kTv8p!iualt2^X$_1w+bB7+@4C_%{@Pt$x*bec(^Q_Mapd<
zSvZDm?SepW+ReJ7ap_ti?t5b5Jcsfm@U2?QSDWmgu8!I2&3s@hx~D^&w1)2K4-#HC
z>s9nD!qIo6*o_CMDK2lmUO6{hjj(<3r6v)71Jwtx`t(=}lq$`rCbQVvh`Ca}MTot&
zdiqQ;z2n%cXN0Cz>2jt13(1ck6{b-s?`5l^poymGq;<OSoQjUuG68#w#S)OgkG4D6
z33XJA#lCSg3B{)N-$>lga;>2*dM4s^$K^NQ*r0d7DU!v{r^;xjZ!}3g9nnIKY;COC
zJfZ__E7n@wD_87)bXU0|rEWbXx0$s|<~_#bos0Bgyj}ZvpcU^XKVNO*NNeqhI^EAV
zA^Bo#l@GQM`ezQhmFgD8n>Hp(?`t|`HXrR#|FK`v8h<j$L16Yx)={O&{nbLBOhBlf
zrTF{ra$TRGKK09J`hIFPdu*<2r$Dn-e{yiSS0Wo~Mh%lut&Yx;2v5D<LojQS(^fvo
z?R%(#X(*8KKq>9V*snb<>#!Q`;?GP={AoQ-dlxiZ0nE3YpDHBScS_(AeZq35C=QB&
z5bXxOjR7yKKG&eo*A6v*vNE%{gVx*FYi{{cbG<{9@0j_)YrLueI~gXQi6KXeyWqI}
z$IJLK24Yu7M?u1hV>5^`hYt2^TL>H+HdW={WzBsoa?*cJu*rTscId5XcYcWRSvS3l
zg&({o6tYJ(#TOxg#%$$JXdP%z$4;(Z2-xn~ifpT67FWucnOnp8tr42SW3$KZ#NHGw
zULG08i!f1nozX1R&=~_3hF4r;4hvv+Jyq?bK3GxgzxTD_!Qt9u+OyJB0WC*ZBz>^T
zN>4c>BHFVQH>(`dV<`Lk*;I_!IULd!zt-KG9PPTdc)GalWw`STz%qC1SoSi@gQw_e
zF>&F#nzrNcSr@9Wb{ib$zf|CipodP~xt3;9o(GQ*PDus6xcI&~h{;@EaS%ahJh&1Z
zuL=xuYc5;WwJg(ZbEqTa2hZkspNh=6jC_$(AYdrX^>Edym#P}gh4UA>C`6+Yx!7mf
z1Dh^WZ7*N%o{m>oZzm|KIfS3r4PJh^Z0Esf;q08kVO*6Len>CXGS;Bz7A-=D0X@-7
z-Kl=QOydN1iY#xiLiQ@hTu+)IOc!*n#qcrlpqs80Y=H^3+H-7T#iijgX3SUU#P(|D
zgc>*Z*cU^>R^Q=~@J}wrr%u7jvP2ExnK$-pqFWnt9^_Y|^IhLfTfr+@Q^H@Xe+<GU
zKL%4<n;y*E|HMr77|TPwj@mEYW$P`ro6X7M3a1R8EidVBj3%q}qy;Xyyz8X5KanK*
zE#EX28pid7X-R0tmCiP2Ji5`hgyzlIf@d@<BgewfaL??a>n#M{`Ve~tzXEQSn^0MY
z4XW~Q1zBksmk!Z5aoZ{+9R*SzFLg7hO<k>g6{ke$cT^CU#P5b)L~O6PM|^InNgw1H
zG%`<)%(4-t%Kq8`6SK3>oBu+k{(jj%L*wF!;QWi-iO~I$8pQh;=gA&i0$cRJfSeV(
zS>tjVfd>OVYAnucB*LX0w)&32#?OWQYb_K1(`BYf4paS1T3dd<hyc4sV52kPi<Fku
zI``+VCRcv$?wD0lLSO2e^5<{dEdFHc59je3j$^n9o5-2lKWXW$X<?ixV><by^G)r5
zoPqU#-;Bke&kHKa(-!LD2L;#9_b_j-2;tXe#c$6wYj&NvB_MomEAG^g8=F^0II=;k
z_8M1~Ge;_JC`Sc9?lALoCgbZH9j&c=?-C{ddcl#vPlpvhUSE8Ro;#>TDAZ4cFd!Ji
z-T7=~6TM=NGNr43RZ|OWXMs&E=a}H1&3s#RE_t56bP-(hHNIgxNR|+`4y|n(F_?%p
zU$}K{p6$>}4{0^dmO<sxj_}C_?ppYgN<c$PCGjTYRp0BL==GOj8`Ga`A{SSRGWiQ5
zG%kC-nAkp9`*Dr=qz_Ma!hLu?f5P1L;$Eurd(!Fx-DEFZ77XIHcjng~KR~^Vmo8fg
z>RByb`}}mqY?K2<kJ|Wh!#%<`>f8Edo`&UNUd6%o3wANu0nQ4ni@9c0=UMc>Rx>Rr
z6v%0Hs!vSW4+ttvzSYmZRM<0BS6(u;KoCcAAvXfiq3b8ED{fC54DehKWS6K8OR%DW
zfKHpo?-OCjWK}I%-kY5F2EW4I@rb*bGyVqLZza>NY-70Z-kP8RgtD)eVygRfyU%dd
z1JBK#a3T}t(fTwSHN6s%vph2U<BsQ_Wqwuc-d}Ls^0W)=yb<T<N%!<Bze@3Qry2Jt
zL#H6d^-jEp!jZx=4)>}0GQUI*eBiv>=eqPkdRXSm${fN$`deAHrejXBH`tSvmVM)c
zzAcAS>|+_PbnEI1QLO2Y)LZKZZb&y4b|~=TXC^{3b@iewp1Hp*S^Z>-?NvNjUIeGn
zBb*-%sR0-#G!97D%Q9DfT92r+OGT#fHWq$#sA&pPK)zlZD)hQ_sU)jenlYarVsws2
zrs(>K#~rTyRpSdZnHg5k@7;556I)Ww0dO7wZe$t?nD~KvOfeVwRq?pTLQ0dVMpJi?
z0M5_LUV9Zh&F$C=Zu9HgUNS;k1?5@+tD-hf8xR&~2vUYWe?9p1OTtkG79|BnDeY=1
veb;t)n{E-^0`V7#&4nPtVydXJZz=$#ckAGq8sm>Ue|M^<Wvp4I?iBq$FFqM=

literal 0
HcmV?d00001

diff --git a/index.pug b/index.pug
index 2c91f12a52a..7d31aced81b 100644
--- a/index.pug
+++ b/index.pug
@@ -350,7 +350,7 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/leo-boost1/f744783/logo/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://poprey.com/">
-                <img class="sponsor" src="https://images.opencollective.com/jean-mir/1bfbe97/avatar/256.png" style="height: 100px">
+                <img class="sponsor" src="/docs/images/logo-poprey-com-white-100.png" style="height: 100px">
               </a>
             </div>
           </div>

From f2651d73a08fe65c75c7172aa704fcd0267c428a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 19 Mar 2021 16:23:50 -0400
Subject: [PATCH 1807/2348] docs(transactions): introduce
 `session.withTransaction()` before `session.startTransaction()` because
 `withTransaction()` is the recommended approach

Fix #10008
---
 docs/transactions.pug                 |  71 +++++++----------
 test/es-next/transactions.test.es6.js | 105 +++++++++++++-------------
 2 files changed, 83 insertions(+), 93 deletions(-)

diff --git a/docs/transactions.pug b/docs/transactions.pug
index 0aab8125ec8..a5ec5ddd7ee 100644
--- a/docs/transactions.pug
+++ b/docs/transactions.pug
@@ -27,53 +27,17 @@ block content
     in isolation and potentially undo all the operations if one of them fails.
     This guide will get you started using transactions with Mongoose.
 
-    ## Your First Transaction
+    ## Getting Started with Transactions
 
-    [MongoDB currently only supports transactions on replica sets](https://docs.mongodb.com/manual/replication/#transactions),
-    not standalone servers. To run a
-    [local replica set for development](http://thecodebarbarian.com/introducing-run-rs-zero-config-mongodb-runner.html)
-    on macOS, Linux or Windows, use npm to install
-    [run-rs](https://www.npmjs.com/package/run-rs) globally and run
-    `run-rs --version 4.0.0`. Run-rs will download MongoDB 4.0.0 for you.
-
-    To use transactions with Mongoose, you should use Mongoose `>= 5.2.0`. To
-    check your current version of Mongoose, run `npm list | grep "mongoose"`
-    or check the [`mongoose.version` property](http://mongoosejs.com/docs/api.html#mongoose_Mongoose-version).
-
-    Transactions are built on [MongoDB sessions](https://docs.mongodb.com/manual/reference/server-sessions/).
-    To start a transaction, you first need to call [`startSession()`](/docs/api.html#startsession_startSession)
-    and then call the session's `startTransaction()` function. To execute an
-    operation in a transaction, you need to pass the `session` as an option.
+    To create a transaction, you first need to create a session using or [`Mongoose#startSession`](/docs/api/mongoose.html#mongoose_Mongoose-startSession)
+    or [`Connection#startSession()`](/docs/api/connection.html#connection_Connection-startSession).
 
     ```javascript
-    [require:transactions.*basic example]
+    const session = await mongoose.startSession();
     ```
 
-    In the above example, `session` is an instance of the
-    [MongoDB Node.js driver's `ClientSession` class](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html).
-    Please refer to the [MongoDB driver docs](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html)
-    for more information on what methods `session` has.
-
-    ## Aborting a Transaction
-
-    The most important feature of transactions is the ability to roll back _all_
-    operations in the transaction using the [`abortTransaction()` function](https://docs.mongodb.com/manual/reference/method/Session.abortTransaction/).
-
-    Think about [modeling a bank account in Mongoose](https://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html#transactions-with-mongoose).
-    To transfer money from account `A` to account `B`, you would decrement
-    `A`'s balance and increment `B`'s balance. However, if `A` only has a balance
-    of $5 and you try to transfer $10, you want to abort the transaction and undo
-    incrementing `B`'s balance.
-
-    ```javascript
-    [require:transactions.*abort]
-    ```
-
-    ## The `withTransaction()` Helper
-
-    The previous examples explicitly create a transaction and commits it. In
-    practice, you'll want to use the [`session.withTransaction()` helper](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction)
-    instead. The `session.withTransaction()` helper handles:
+    In practice, you should use either the [`session.withTransaction()` helper](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction)
+    or Mongoose's `Connection#transaction()` function to run a transaction. The `session.withTransaction()` helper handles:
     
     - Creating a transaction
     - Committing the transaction if it succeeds
@@ -87,6 +51,14 @@ block content
     For more information on the `ClientSession#withTransaction()` function, please see
     [the MongoDB Node.js driver docs](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction). 
 
+    Mongoose's `Connection#transaction()` function is a wrapper around `withTransaction()` that
+    integrates Mongoose change tracking with transactions. For example, the `Connection#transaction()`
+    function handles resetting a document if you `save()` that document in a transaction that later fails.
+
+    ```javascript
+    [require:transactions.*can save document after aborted transaction]
+    ```
+
     ## With Mongoose Documents and `save()`
 
     If you get a [Mongoose document](/docs/documents.html) from [`findOne()`](/docs/api.html#findone_findOne)
@@ -109,3 +81,18 @@ block content
     ```javascript
     [require:transactions.*aggregate]
     ```
+
+    ## Advanced Usage
+
+    Advanced users who want more fine-grained control over when they commit or abort transactions
+    can use `session.startTransaction()` to start a transaction:
+
+    ```javascript
+    [require:transactions.*basic example]
+    ```
+
+    You can also use `session.abortTransaction()` to abort a transaction:
+
+    ```javascript
+    [require:transactions.*abort]
+    ```
\ No newline at end of file
diff --git a/test/es-next/transactions.test.es6.js b/test/es-next/transactions.test.es6.js
index 5f28ec7692d..bbf05bdde70 100644
--- a/test/es-next/transactions.test.es6.js
+++ b/test/es-next/transactions.test.es6.js
@@ -127,25 +127,25 @@ describe('transactions', function() {
     await User.createCollection();
     // acquit:ignore:end
     const session = await db.startSession();
-    session.startTransaction();
-
-    await User.create({ name: 'foo' });
-
-    const user = await User.findOne({ name: 'foo' }).session(session);
-    // Getter/setter for the session associated with this document.
-    assert.ok(user.$session());
-    user.name = 'bar';
-    // By default, `save()` uses the associated session
-    await user.save();
 
-    // Won't find the doc because `save()` is part of an uncommitted transaction
-    let doc = await User.findOne({ name: 'bar' });
-    assert.ok(!doc);
+    await session.withTransaction(async () => {
+      await User.create({ name: 'foo' });
+
+      const user = await User.findOne({ name: 'foo' }).session(session);
+      // Getter/setter for the session associated with this document.
+      assert.ok(user.$session());
+      user.name = 'bar';
+      // By default, `save()` uses the associated session
+      await user.save();
+
+      // Won't find the doc because `save()` is part of an uncommitted transaction
+      const doc = await User.findOne({ name: 'bar' });
+      assert.ok(!doc);
+    });
 
-    await session.commitTransaction();
     session.endSession();
 
-    doc = await User.findOne({ name: 'bar' });
+    const doc = await User.findOne({ name: 'bar' });
     assert.ok(doc);
   });
 
@@ -174,35 +174,35 @@ describe('transactions', function() {
     await Event.createCollection();
     // acquit:ignore:end
     const session = await db.startSession();
-    session.startTransaction();
-
-    await Event.insertMany([
-      { createdAt: new Date('2018-06-01') },
-      { createdAt: new Date('2018-06-02') },
-      { createdAt: new Date('2017-06-01') },
-      { createdAt: new Date('2017-05-31') }
-    ], { session: session });
-
-    const res = await Event.aggregate([
-      {
-        $group: {
-          _id: {
-            month: { $month: '$createdAt' },
-            year: { $year: '$createdAt' }
-          },
-          count: { $sum: 1 }
-        }
-      },
-      { $sort: { count: -1, '_id.year': -1, '_id.month': -1 } }
-    ]).session(session);
-
-    assert.deepEqual(res, [
-      { _id: { month: 6, year: 2018 }, count: 2 },
-      { _id: { month: 6, year: 2017 }, count: 1 },
-      { _id: { month: 5, year: 2017 }, count: 1 }
-    ]);
+    
+    await session.withTransaction(async () => {
+      await Event.insertMany([
+        { createdAt: new Date('2018-06-01') },
+        { createdAt: new Date('2018-06-02') },
+        { createdAt: new Date('2017-06-01') },
+        { createdAt: new Date('2017-05-31') }
+      ], { session: session });
+  
+      const res = await Event.aggregate([
+        {
+          $group: {
+            _id: {
+              month: { $month: '$createdAt' },
+              year: { $year: '$createdAt' }
+            },
+            count: { $sum: 1 }
+          }
+        },
+        { $sort: { count: -1, '_id.year': -1, '_id.month': -1 } }
+      ]).session(session);
+  
+      assert.deepEqual(res, [
+        { _id: { month: 6, year: 2018 }, count: 2 },
+        { _id: { month: 6, year: 2017 }, count: 1 },
+        { _id: { month: 5, year: 2017 }, count: 1 }
+      ]);
+    });
 
-    await session.commitTransaction();
     session.endSession();
   });
 
@@ -372,12 +372,15 @@ describe('transactions', function() {
 
   it('can save document after aborted transaction (gh-8380)', async function() {
     const schema = Schema({ name: String, arr: [String], arr2: [String] });
+    // acquit:ignore:start
+    db.deleteModel(/Test/);
+    // acquit:ignore:end
 
-    const Test = db.model('gh8380', schema);
+    const Test = db.model('Test', schema);
 
     await Test.createCollection();
-    await Test.create({ name: 'foo', arr: ['bar'], arr2: ['foo'] });
-    const doc = await Test.findOne();
+    let doc = await Test.create({ name: 'foo', arr: ['bar'], arr2: ['foo'] });
+    doc = await Test.findById(doc);
     await db.
       transaction(async (session) => {
         doc.arr.pull('bar');
@@ -391,7 +394,7 @@ describe('transactions', function() {
         assert.equal(err.message, 'Oops');
       });
 
-    const changes = doc.$__delta()[1];
+    const changes = doc.getChanges();
     assert.equal(changes.$set.name, 'baz');
     assert.deepEqual(changes.$pullAll.arr, ['bar']);
     assert.deepEqual(changes.$push.arr2, { $each: ['bar'] });
@@ -399,7 +402,7 @@ describe('transactions', function() {
 
     await doc.save({ session: null });
 
-    const newDoc = await Test.collection.findOne();
+    const newDoc = await Test.findById(doc);
     assert.equal(newDoc.name, 'baz');
     assert.deepEqual(newDoc.arr, []);
     assert.deepEqual(newDoc.arr2, ['foo', 'bar']);
@@ -408,7 +411,7 @@ describe('transactions', function() {
   it('can save a new document with an array', async function () {
     const schema = Schema({ arr: [String] });
 
-    const Test = db.model('new_doc_array', schema);
+    const Test = db.model('new_doc_array1', schema);
 
     await Test.createCollection();
     const doc = new Test({ arr: ['foo'] });
@@ -423,14 +426,14 @@ describe('transactions', function() {
   it('can save a new document with an array and read within transaction', async function () {
     const schema = Schema({ arr: [String] });
 
-    const Test = db.model('new_doc_array', schema);
+    const Test = db.model('new_doc_array2', schema);
 
     await Test.createCollection();
     const doc = new Test({ arr: ['foo'] });
     await db.transaction(
       async (session) => {
         await doc.save({ session });
-        const testDocs = await Test.collection.find({}).session(session);
+        const testDocs = await Test.find({}).session(session);
         assert.deepStrictEqual(testDocs.length, 1);
       },
       { readPreference: 'primary' }

From 7b14258e4a9ac09bec65a2674d4d9cc93278d0c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 19 Mar 2021 16:26:11 -0400
Subject: [PATCH 1808/2348] test(QueryCursor): fix tests from #10015

---
 test/query.cursor.test.js | 19 ++-----------------
 1 file changed, 2 insertions(+), 17 deletions(-)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 7194ead035e..46751ab9cc1 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -692,8 +692,8 @@ describe('QueryCursor', function() {
 
   it('post hooks (gh-9435)', function() {
     const schema = new mongoose.Schema({ name: String });
-    schema.post('find', function(doc) {
-      doc.name = doc.name.toUpperCase();
+    schema.post('find', function(docs) {
+      docs.forEach(doc => { doc.name = doc.name.toUpperCase(); });
     });
     const Movie = db.model('Movie', schema);
 
@@ -711,19 +711,4 @@ describe('QueryCursor', function() {
       assert.deepEqual(arr, ['KICKBOXER', 'IP MAN', 'ENTER THE DRAGON']);
     });
   });
-  it('returns array for schema hooks gh-9982', () => {
-    const testSchema = new mongoose.Schema({ name: String });
-    testSchema.post('find', (result) => {
-      assert.ok(Array.isArray(result));
-    });
-    const Movie = db.model('Movie', testSchema);
-    return co(function*() {
-      yield Movie.deleteMany({});
-      yield Movie.create({ name: 'Daniel' }, { name: 'Val' }, { name: 'Daniel' });
-     const test = Movie.find({ name: 'Daniel' }).cursor();
-     test.next().then(doc => {
-       assert.ok(doc,doc);
-     });
-    });
-  });
 });

From 03905c5567ef1b310eb0e7a34b1049b973ecf951 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 19 Mar 2021 17:09:10 -0400
Subject: [PATCH 1809/2348] fix(index.d.ts): always allow setting `type` in
 Schema to a SchemaType class or a Schema instance

Fix #10030
---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 2b41c6ec232..3a3f310d2ca 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1383,9 +1383,9 @@ declare module 'mongoose' {
   export class SchemaTypeOptions<T> {
     type?:
       T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
-      T extends Schema<any> ? T :
+      T extends Schema ? T :
       T extends object[] ? Schema<Document<Unpacked<T>>>[] :
-      T;
+      T | typeof SchemaType | Schema;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;

From 58882692bc64f103c76cf12972340f55bc2facfa Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 19 Mar 2021 17:23:36 -0400
Subject: [PATCH 1810/2348] docs(mongoose+browser): fix broken links to info
 about `mongoose.Types`

Fix #10016
---
 lib/browser.js | 13 ++++++++-----
 lib/index.js   | 13 ++++++++-----
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/lib/browser.js b/lib/browser.js
index f716f2aee71..f71a4793cb4 100644
--- a/lib/browser.js
+++ b/lib/browser.js
@@ -68,11 +68,14 @@ exports.Schema = require('./schema');
  *
  * ####Types:
  *
- * - [ObjectId](#types-objectid-js)
- * - [Buffer](#types-buffer-js)
- * - [SubDocument](#types-embedded-js)
- * - [Array](#types-array-js)
- * - [DocumentArray](#types-documentarray-js)
+ * - [Array](/docs/schematypes.html#arrays)
+ * - [Buffer](/docs/schematypes.html#buffers)
+ * - [Embedded](/docs/schematypes.html#schemas)
+ * - [DocumentArray](/docs/api/documentarraypath.html)
+ * - [Decimal128](/docs/api.html#mongoose_Mongoose-Decimal128)
+ * - [ObjectId](/docs/schematypes.html#objectids)
+ * - [Map](/docs/schematypes.html#maps)
+ * - [Subdocument](/docs/schematypes.html#schemas)
  *
  * Using this exposed access to the `ObjectId` type, we can construct ids on demand.
  *
diff --git a/lib/index.js b/lib/index.js
index 6337e8dcb65..c46cf543585 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -866,11 +866,14 @@ Mongoose.prototype.VirtualType = VirtualType;
  *
  * ####Types:
  *
- * - [ObjectId](#types-objectid-js)
- * - [Buffer](#types-buffer-js)
- * - [SubDocument](#types-embedded-js)
- * - [Array](#types-array-js)
- * - [DocumentArray](#types-documentarray-js)
+ * - [Array](/docs/schematypes.html#arrays)
+ * - [Buffer](/docs/schematypes.html#buffers)
+ * - [Embedded](/docs/schematypes.html#schemas)
+ * - [DocumentArray](/docs/api/documentarraypath.html)
+ * - [Decimal128](/docs/api.html#mongoose_Mongoose-Decimal128)
+ * - [ObjectId](/docs/schematypes.html#objectids)
+ * - [Map](/docs/schematypes.html#maps)
+ * - [Subdocument](/docs/schematypes.html#schemas)
  *
  * Using this exposed access to the `ObjectId` type, we can construct ids on demand.
  *

From 1bb97ba8caaf0cbcd4e3bee1238eae92722cc59b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 19 Mar 2021 17:30:20 -0400
Subject: [PATCH 1811/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 7d31aced81b..4925a58678d 100644
--- a/index.pug
+++ b/index.pug
@@ -352,6 +352,9 @@ html(lang='en')
               <a rel="sponsored" href="https://poprey.com/">
                 <img class="sponsor" src="/docs/images/logo-poprey-com-white-100.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://casinomartini.com/">
+                <img class="sponsor" src="https://images.opencollective.com/casino-martini/8efce1c/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 9559c4654fb5f826838a07b9093bb44785d2c06e Mon Sep 17 00:00:00 2001
From: SoftwareSing <softwaresing@gmail.com>
Date: Sat, 20 Mar 2021 21:16:29 +0800
Subject: [PATCH 1812/2348] test(bulkwrite): repro #10048

---
 test/model.test.js | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 818a23a79dc..41185f2151c 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5780,6 +5780,35 @@ describe('Model', function() {
           assert.equal(people[3].age, 30);
         });
       });
+
+      it('insertOne and replaceOne should not throw an error when set `timestamps: false` in schmea', function() {
+        const schema = new Schema({ name: String }, { timestamps: false });
+        const Model = db.model('Test', schema);
+
+        return co(function*() {
+          yield Model.create({ name: 'test' });
+
+          yield Model.bulkWrite([
+            {
+              insertOne: {
+                document: { name: 'insertOne-test' }
+              }
+            },
+            {
+              replaceOne: {
+                filter: { name: 'test' },
+                replacement: { name: 'replaceOne-test' }
+              }
+            }
+          ]);
+
+          for (const name of ['insertOne-test', 'replaceOne-test']) {
+            const doc = yield Model.findOne({ name });
+            assert.strictEqual(doc.createdAt, undefined);
+            assert.strictEqual(doc.updatedAt, undefined);
+          }
+        });
+      });
     });
 
     it('insertMany with Decimal (gh-5190)', function(done) {

From 0101ab8e07f32ae3f98f01e2c4cec12cc6874234 Mon Sep 17 00:00:00 2001
From: SoftwareSing <softwaresing@gmail.com>
Date: Sat, 20 Mar 2021 21:20:21 +0800
Subject: [PATCH 1813/2348] fix(bulkwrite): make bulkWrite can work with
 `timestamps: false`

fixes #10048
---
 lib/helpers/model/castBulkWrite.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index 6e7a8300754..d3aaea99f08 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -20,7 +20,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
       const model = decideModelByObject(originalModel, op['insertOne']['document']);
 
       const doc = new model(op['insertOne']['document']);
-      if (model.schema.options.timestamps != null) {
+      if (doc.initializeTimestamps) {
         doc.initializeTimestamps();
       }
       if (options.session != null) {
@@ -147,7 +147,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
 
       // set `skipId`, otherwise we get "_id field cannot be changed"
       const doc = new model(op['replaceOne']['replacement'], strict, true);
-      if (model.schema.options.timestamps != null) {
+      if (doc.initializeTimestamps) {
         doc.initializeTimestamps();
       }
       if (options.session != null) {

From 003e4777130194a8cfdb35e53c0deedd53690b7e Mon Sep 17 00:00:00 2001
From: SoftwareSing <softwaresing@gmail.com>
Date: Sat, 20 Mar 2021 21:27:41 +0800
Subject: [PATCH 1814/2348] add missing issue number

---
 test/model.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 41185f2151c..596f66d91e6 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5781,7 +5781,7 @@ describe('Model', function() {
         });
       });
 
-      it('insertOne and replaceOne should not throw an error when set `timestamps: false` in schmea', function() {
+      it('insertOne and replaceOne should not throw an error when set `timestamps: false` in schmea (gh-10048)', function() {
         const schema = new Schema({ name: String }, { timestamps: false });
         const Model = db.model('Test', schema);
 

From 00e059d17594ea04b2a8b8a3c97650340b4a4281 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 11:05:06 -0400
Subject: [PATCH 1815/2348] fix(index.d.ts): add `upserted` array to
 `updateOne()`, `updateMany()`, `update()` result

Fix #10042
---
 index.d.ts | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3a3f310d2ca..c2936b88d7a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -848,13 +848,13 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<mongodb.WriteOpResult['result'], T, TQueryHelpers>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<mongodb.UpdateWriteOpResult['result'], T, TQueryHelpers>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<mongodb.UpdateWriteOpResult['result'], T, TQueryHelpers>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
@@ -862,6 +862,11 @@ declare module 'mongoose' {
     where(): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
   }
 
+  type _UpdateWriteOpResult = mongodb.UpdateWriteOpResult['result'];
+  interface UpdateWriteOpResult extends _UpdateWriteOpResult {
+    upserted?: Array<{index: number, _id: any}>;
+  }
+
   interface QueryOptions {
     arrayFilters?: { [key: string]: any }[];
     batchSize?: number;
@@ -2191,7 +2196,7 @@ declare module 'mongoose' {
     toConstructor(): new (...args: any[]) => Query<ResultType, DocType, THelpers>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): Query<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -2199,13 +2204,13 @@ declare module 'mongoose' {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): Query<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): Query<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,

From 9a3a7b4aa66b71d940b60b5455ea37ffedb7693b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 11:13:02 -0400
Subject: [PATCH 1816/2348] style: fix lint

---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index ad1f89bb10a..994c9d8c7d6 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -468,7 +468,7 @@ Schema.prototype.add = function add(obj, prefix) {
   prefix = prefix || '';
   // avoid prototype pollution
   if (prefix === '__proto__.' || prefix === 'constructor.' || prefix === 'prototype.') {
-        return this;
+    return this;
   }
 
   const keys = Object.keys(obj);

From 04f880f1b7d0d4f1c2884501f2ff3224f6547e87 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 11:16:30 -0400
Subject: [PATCH 1817/2348] fix(index.d.ts): add back `Aggregate#project()`
 types that were mistakenly removed in 5.12.0

Fix #10043
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index c2936b88d7a..f7e55c951c5 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2439,6 +2439,9 @@ declare module 'mongoose' {
     /** Returns the current pipeline */
     pipeline(): any[];
 
+    /** Appends a new $project operator to this aggregate pipeline. */
+    project(arg: string | Object): this;
+
     /** Sets the readPreference option for the aggregation query. */
     read(pref: string | mongodb.ReadPreferenceMode, tags?: any[]): this;
 

From 96f7905f21e9a1004eaea8713ab1df1c3ee40d80 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 13:01:42 -0400
Subject: [PATCH 1818/2348] fix(index.d.ts): make query methods return
 `QueryWithHelpers` so query helpers pass through chaining

Fix #10040
---
 index.d.ts                 | 66 ++++++++++++++++++++------------------
 test/typescript/queries.ts | 10 +++---
 2 files changed, 39 insertions(+), 37 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index f7e55c951c5..01cb6ac41c2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1064,6 +1064,8 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
+  type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
+
   class Schema<DocType extends Document = Document, M extends Model<DocType, any> = Model<any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
@@ -1167,7 +1169,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: <T extends Query<any, any, any> = Query<any, any, any>>(this: T, ...args: any[]) => any };
+    query: { [name: string]: <T extends QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>> = QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
@@ -1852,7 +1854,7 @@ declare module 'mongoose' {
     exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
 
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): Query<DocType[], DocType, THelpers>;
+    $where(argument: string | Function): QueryWithHelpers<DocType[], DocType, THelpers>;
 
     /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     all(val: Array<any>): this;
@@ -1888,12 +1890,12 @@ declare module 'mongoose' {
     comment(val: string): this;
 
     /** Specifies this query as a `count` query. */
-    count(callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
-    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
+    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
+    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
 
     /** Specifies this query as a `countDocuments` query. */
-    countDocuments(callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
-    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
+    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
+    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
 
     /**
      * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
@@ -1906,17 +1908,17 @@ declare module 'mongoose' {
      * remove, except it deletes _every_ document that matches `filter` in the
      * collection, regardless of the value of `single`.
      */
-    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
+    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as a `deleteOne()` operation. Works like
      * remove, except it deletes at most one document regardless of the `single`
      * option.
      */
-    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): Query<any, DocType, THelpers>;
+    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): Query<Array<any>, DocType, THelpers>;
+    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     // eslint-disable-next-line @typescript-eslint/ban-types
@@ -1935,7 +1937,7 @@ declare module 'mongoose' {
     equals(val: any): this;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): Query<number, DocType, THelpers>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
 
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
@@ -1950,31 +1952,31 @@ declare module 'mongoose' {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers>;
-    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): Query<Array<DocType>, DocType, THelpers>;
+    find(callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers>;
+    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
-    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): Query<DocType | null, DocType, THelpers>;
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
+    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
+    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType, THelpers>;
-    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
+    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): Query<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): Query<DocType, DocType, THelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): Query<DocType | null, DocType, THelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Specifies a `$geometry` condition */
     geometry(object: { type: string, coordinates: any[] }): this;
@@ -2023,7 +2025,7 @@ declare module 'mongoose' {
     j(val: boolean | null): this;
 
     /** Sets the lean option. */
-    lean<LeanResultType = LeanDocumentOrArray<ResultType>>(val?: boolean | any): Query<LeanResultType, DocType, THelpers>;
+    lean<LeanResultType = LeanDocumentOrArray<ResultType>>(val?: boolean | any): QueryWithHelpers<LeanResultType, DocType, THelpers>;
 
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
@@ -2040,7 +2042,7 @@ declare module 'mongoose' {
      * Runs a function `fn` and treats the return value of `fn` as the new value
      * for the query to resolve to.
      */
-    map<MappedType>(fn: (doc: DocType) => MappedType): Query<MappedType, DocType, THelpers>;
+    map<MappedType>(fn: (doc: DocType) => MappedType): QueryWithHelpers<MappedType, DocType, THelpers>;
 
     /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     maxDistance(val: number): this;
@@ -2092,7 +2094,7 @@ declare module 'mongoose' {
      * This is handy for integrating with async/await, because `orFail()` saves you
      * an extra `if` statement to check if no document was found.
      */
-    orFail(err?: NativeError | (() => NativeError)): Query<NonNullable<ResultType>, DocType, THelpers>;
+    orFail(err?: NativeError | (() => NativeError)): QueryWithHelpers<NonNullable<ResultType>, DocType, THelpers>;
 
     /** Specifies a `$polygon` condition */
     polygon(...coordinatePairs: number[][]): this;
@@ -2120,14 +2122,14 @@ declare module 'mongoose' {
      * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
      * or [`deleteMany()`](#query_Query-deleteMany) instead.
      */
-    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): Query<mongodb.WriteOpResult['result'], DocType, THelpers>;
+    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): QueryWithHelpers<mongodb.WriteOpResult['result'], DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as a replaceOne() operation. Same as
      * `update()`, except MongoDB will replace the existing document and will
      * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
      */
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, DocType, THelpers>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
 
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;
@@ -2193,10 +2195,10 @@ declare module 'mongoose' {
     then: Promise<ResultType>['then'];
 
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
-    toConstructor(): new (...args: any[]) => Query<ResultType, DocType, THelpers>;
+    toConstructor(): new (...args: any[]) => QueryWithHelpers<ResultType, DocType, THelpers>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): Query<UpdateWriteOpResult, DocType, THelpers>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -2204,13 +2206,13 @@ declare module 'mongoose' {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): Query<UpdateWriteOpResult, DocType, THelpers>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): Query<UpdateWriteOpResult, DocType, THelpers>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 26427361764..f41cb35b1f2 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,16 +1,16 @@
-import { Schema, model, Document, Types, Query, Model } from 'mongoose';
+import { Schema, model, Document, Types, Query, Model, QueryWithHelpers } from 'mongoose';
 
 interface QueryHelpers {
-  byName(name: string): Query<Array<ITest>, ITest, QueryHelpers>;
+  byName(name: string): QueryWithHelpers<Array<ITest>, ITest, QueryHelpers>;
 }
 
-const schema: Schema<ITest, Model<ITest>> = new Schema({
+const schema: Schema<ITest, Model<ITest, QueryHelpers>> = new Schema({
   name: { type: 'String' },
   tags: [String],
   docs: [{ nested: { id: Number } }]
 });
 
-schema.query.byName = function(name: string): Query<Array<ITest>, ITest, QueryHelpers> {
+schema.query.byName = function(name: string): Query<any, ITest, QueryHelpers> & QueryHelpers {
   return this.find({ name });
 };
 
@@ -28,7 +28,7 @@ interface ITest extends Document {
 
 const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
 
-Test.find().byName('test').orFail().exec().then(console.log);
+Test.find().byName('test').byName('test2').orFail().exec().then(console.log);
 
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));
 Test.findOne({ 'docs.id': 42 }).exec().then(console.log);

From 171c31faaf1dfb1875efb58d84e53872432fb537 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 16:21:04 -0400
Subject: [PATCH 1819/2348] test(schema): repro #10029

---
 test/schema.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 8dfe1b312a4..08d3deef563 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2578,4 +2578,20 @@ describe('schema', function() {
 
     assert.equal(schema.virtuals.displayAs.applyGetters(null, { name: 'test' }), 'test');
   });
+
+  it('supports setting `ref` on array SchemaType (gh-10029)', function() {
+    const testSchema = new mongoose.Schema({
+      doesntpopulate: {
+        type: [mongoose.Schema.Types.ObjectId],
+        ref: 'features'
+      },
+      populatescorrectly: [{
+        type: mongoose.Schema.Types.ObjectId,
+        ref: 'features'
+      }]
+    });
+
+    assert.equal(testSchema.path('doesntpopulate.$').options.ref, 'features');
+    assert.equal(testSchema.path('populatescorrectly.$').options.ref, 'features');
+  });
 });

From 4b0052ebb656bb6ab73535c1cddcf0f8811b89e1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 16:21:22 -0400
Subject: [PATCH 1820/2348] fix(schema): support setting `ref` as an option on
 an array SchemaType

Re: #10029
---
 lib/schema/array.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index c113cb6bec8..93d26741d32 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -60,6 +60,10 @@ function SchemaArray(key, cast, options, schemaOptions) {
       }
     }
 
+    if (options != null && options.ref != null && castOptions.ref == null) {
+      castOptions.ref = options.ref;
+    }
+
     if (cast === Object) {
       cast = Mixed;
     }

From 7d19c9fdb1cacaf37b067e9fb138ba3a4b18b40a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 16:38:54 -0400
Subject: [PATCH 1821/2348] test(query): repro #10029

---
 test/query.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index f5659e87a96..e8cb49c9d17 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3757,4 +3757,23 @@ describe('Query', function() {
       assert.equal(called.length, 1);
     });
   });
+
+  it('applies schema-level `select` on arrays (gh-10029)', function() {
+    const testSchema = new mongoose.Schema({
+      doesntpopulate: {
+        type: [mongoose.Schema.Types.ObjectId],
+        select: false
+      },
+      populatescorrectly: [{
+        type: mongoose.Schema.Types.ObjectId,
+        select: false
+      }]
+    });
+    const Test = db.model('Test', testSchema);
+
+    const q = Test.find();
+    q._applyPaths();
+
+    assert.deepEqual(q._fields, { doesntpopulate: 0, populatescorrectly: 0 });
+  });
 });

From 5ffbb8ecf45bee9ea92400144a735a86ba22bfd3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 16:39:09 -0400
Subject: [PATCH 1822/2348] fix(query): apply schema-level `select` option from
 array schematypes

Fix #10029
---
 lib/queryhelpers.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 26c2386b7fc..79f4dc50a5e 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -199,7 +199,11 @@ exports.applyPaths = function applyPaths(fields, schema) {
     schema.eachPath(function(path, type) {
       if (prefix) path = prefix + '.' + path;
 
-      const addedPath = analyzePath(path, type);
+      let addedPath = analyzePath(path, type);
+      // arrays
+      if (addedPath == null && type.$isMongooseArray && !type.$isMongooseDocumentArray) {
+        addedPath = analyzePath(path, type.caster);
+      }
       if (addedPath != null) {
         addedPaths.push(addedPath);
       }

From 3759f3405b986b877461f9ef0b978b193fba759b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 16:42:40 -0400
Subject: [PATCH 1823/2348] chore: address CR comments

---
 lib/helpers/model/castBulkWrite.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index d3aaea99f08..d3f0e9a2e1d 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -20,7 +20,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
       const model = decideModelByObject(originalModel, op['insertOne']['document']);
 
       const doc = new model(op['insertOne']['document']);
-      if (doc.initializeTimestamps) {
+      if (model.schema.options.timestamps) {
         doc.initializeTimestamps();
       }
       if (options.session != null) {
@@ -147,7 +147,7 @@ module.exports = function castBulkWrite(originalModel, op, options) {
 
       // set `skipId`, otherwise we get "_id field cannot be changed"
       const doc = new model(op['replaceOne']['replacement'], strict, true);
-      if (doc.initializeTimestamps) {
+      if (model.schema.options.timestamps) {
         doc.initializeTimestamps();
       }
       if (options.session != null) {
@@ -221,4 +221,4 @@ function decideModelByObject(model, object) {
     model = getDiscriminatorByValue(model, object[discriminatorKey]) || model;
   }
   return model;
-}
\ No newline at end of file
+}

From 5549f26da208e15e26af9d6929ada350fdf8a8ff Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Mar 2021 16:57:43 -0400
Subject: [PATCH 1824/2348] chore: release 5.12.2

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 1012951d428..a209cb2ca60 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.12.2 / 2021-03-22
+===================
+ * fix(QueryCursor): consistently execute `post('find')` hooks with an array of docs #10015 #9982 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(schema): support setting `ref` as an option on an array SchemaType #10029
+ * fix(query): apply schema-level `select` option from array schematypes #10029
+ * fix(schema): avoid possible prototype pollution with `Schema()` constructor #10035 [zpbrent](https://github.com/zpbrent)
+ * fix(model): make bulkWrite skip timestamps with timestamps: false #10050 [SoftwareSing](https://github.com/SoftwareSing)
+ * fix(index.d.ts): make query methods return `QueryWithHelpers` so query helpers pass through chaining #10040
+ * fix(index.d.ts): add `upserted` array to `updateOne()`, `updateMany()`, `update()` result #10042
+ * fix(index.d.ts): add back `Aggregate#project()` types that were mistakenly removed in 5.12.0 #10043
+ * fix(index.d.ts): always allow setting `type` in Schema to a SchemaType class or a Schema instance #10030
+ * docs(transactions): introduce `session.withTransaction()` before `session.startTransaction()` because `withTransaction()` is the recommended approach #10008
+ * docs(mongoose+browser): fix broken links to info about `mongoose.Types` #10016
+
 5.12.1 / 2021-03-18
 ===================
  * fix: update mongodb -> 3.6.5 to fix circular dependency warning #9900
diff --git a/package.json b/package.json
index 2c06f54a8e6..831487e8618 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.1",
+  "version": "5.12.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 84a87ad503aeb2c532745b23ca5ec05c4271a962 Mon Sep 17 00:00:00 2001
From: Sangwoo <eicpein@gmail.com>
Date: Tue, 23 Mar 2021 09:03:33 +0900
Subject: [PATCH 1825/2348] fix(index.d.ts): add a missing type for
 discriminator

It adds a missing type for discriminator.
This commit will make the following code works in TS.

Image.discriminator<ImageChildDoc, ImageChildModel>('ImageChild', imageChildSchema);
---
 index.d.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/index.d.ts b/index.d.ts
index 01cb6ac41c2..36db57a1878 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -782,6 +782,7 @@ declare module 'mongoose' {
 
     /** Adds a discriminator type. */
     discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
+    discriminator<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(name: string, schema: Schema<T, U>, value?: string): U;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, T, TQueryHelpers>;

From 8018a6ebfd3f47a3db81f237cf92dfd6c16486b0 Mon Sep 17 00:00:00 2001
From: Sangwoo <eicpein@gmail.com>
Date: Tue, 23 Mar 2021 11:29:45 +0900
Subject: [PATCH 1826/2348] Remove unnecessary TQueryHelpers

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 36db57a1878..2a56271cc0c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -782,7 +782,7 @@ declare module 'mongoose' {
 
     /** Adds a discriminator type. */
     discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
-    discriminator<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(name: string, schema: Schema<T, U>, value?: string): U;
+    discriminator<T extends Document, U extends Model>(name: string, schema: Schema<T, U>, value?: string): U;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, T, TQueryHelpers>;

From 6d00af2de2694e295b4dde19d5988dc309ce75d1 Mon Sep 17 00:00:00 2001
From: Sangwoo <eicpein@gmail.com>
Date: Tue, 23 Mar 2021 11:40:38 +0900
Subject: [PATCH 1827/2348] Change Model to model generic

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 2a56271cc0c..77bd306b765 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -782,7 +782,7 @@ declare module 'mongoose' {
 
     /** Adds a discriminator type. */
     discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
-    discriminator<T extends Document, U extends Model>(name: string, schema: Schema<T, U>, value?: string): U;
+    discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, T, TQueryHelpers>;

From 1629e4be5aa84d0475ebb7ed7fdf3cd4df751436 Mon Sep 17 00:00:00 2001
From: Emre <44215156+emrebass@users.noreply.github.com>
Date: Tue, 23 Mar 2021 09:08:43 +0300
Subject: [PATCH 1828/2348] Fix for 'ee.listeners' error

---
 lib/helpers/promiseOrCallback.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/promiseOrCallback.js b/lib/helpers/promiseOrCallback.js
index db16d01f27c..11fff2258ad 100644
--- a/lib/helpers/promiseOrCallback.js
+++ b/lib/helpers/promiseOrCallback.js
@@ -8,7 +8,7 @@ module.exports = function promiseOrCallback(callback, fn, ee, Promise) {
   if (typeof callback === 'function') {
     return fn(function(error) {
       if (error != null) {
-        if (ee != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
+        if (ee != null && ee.listeners != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
           error[emittedSymbol] = true;
           ee.emit('error', error);
         }
@@ -30,7 +30,7 @@ module.exports = function promiseOrCallback(callback, fn, ee, Promise) {
   return new Promise((resolve, reject) => {
     fn(function(error, res) {
       if (error != null) {
-        if (ee != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
+        if (ee != null && ee.listeners != null && ee.listeners('error').length > 0 && !error[emittedSymbol]) {
           error[emittedSymbol] = true;
           ee.emit('error', error);
         }
@@ -42,4 +42,4 @@ module.exports = function promiseOrCallback(callback, fn, ee, Promise) {
       resolve(res);
     });
   });
-};
\ No newline at end of file
+};

From 80245edf5aeab304411681035f7f4153dbd2b692 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 23 Mar 2021 10:03:40 -0400
Subject: [PATCH 1829/2348] chore: update opencollective sponsors

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 4925a58678d..b75c9a89568 100644
--- a/index.pug
+++ b/index.pug
@@ -352,7 +352,7 @@ html(lang='en')
               <a rel="sponsored" href="https://poprey.com/">
                 <img class="sponsor" src="/docs/images/logo-poprey-com-white-100.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://casinomartini.com/">
+              <a rel="sponsored" href="https://casinomartini.com/nz/new-online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casino-martini/8efce1c/logo/256.png" style="height: 100px">
               </a>
             </div>

From b5cace609c1a11995d6d9236b5d0f8725602db67 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 23 Mar 2021 15:34:24 -0400
Subject: [PATCH 1830/2348] Update connection.test.js

---
 test/connection.test.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/connection.test.js b/test/connection.test.js
index 3eab9f19ce9..6a82e0aa76c 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1299,4 +1299,11 @@ describe('connections:', function() {
       assert.ifError(errorOnDisconnect);
     });
   });
+  it('Connection id should be scoped per Mongoose Instance (gh-10025)', function() {
+    const mongoose = require('mongoose');
+    //console.log(new Error().stack);
+    const m = new mongoose.Mongoose();
+    //console.log(new Error().stack);
+    assert.deepStrictEqual(m.connection.id,0);
+  });
 });

From e5ed7365375ca4e792c3e0bc0e4ce5310ad7b83b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 23 Mar 2021 18:01:03 -0400
Subject: [PATCH 1831/2348] Update connection.test.js

---
 test/connection.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index 6a82e0aa76c..ed8dffcd7d9 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1301,9 +1301,9 @@ describe('connections:', function() {
   });
   it('Connection id should be scoped per Mongoose Instance (gh-10025)', function() {
     const mongoose = require('mongoose');
-    //console.log(new Error().stack);
+    console.log(mongoose.connection.id);
     const m = new mongoose.Mongoose();
-    //console.log(new Error().stack);
+    console.log(m.connection.id);
     assert.deepStrictEqual(m.connection.id,0);
   });
 });

From ccf5b16e5ddf04fd27af7a51a5d2c41610be88f0 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 10:58:24 -0400
Subject: [PATCH 1832/2348] fixed test case

---
 test/connection.test.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/connection.test.js b/test/connection.test.js
index ed8dffcd7d9..26f6f64e071 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1300,10 +1300,10 @@ describe('connections:', function() {
     });
   });
   it('Connection id should be scoped per Mongoose Instance (gh-10025)', function() {
-    const mongoose = require('mongoose');
-    console.log(mongoose.connection.id);
-    const m = new mongoose.Mongoose();
+    const m = new mongoose.Mongoose;
     console.log(m.connection.id);
-    assert.deepStrictEqual(m.connection.id,0);
+    const m1 = new mongoose.Mongoose;
+    console.log(m1.connection.id);
+    assert.deepStrictEqual(m1.connection.id, 0);
   });
 });

From 6deb668d1d3324b7ce7c02a8d9ac90ec47c0d3c1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 13:31:55 -0400
Subject: [PATCH 1833/2348] fix: connection ids are now scoped

Some tests are failing but they were failing before the changes I made.
---
 lib/connection.js       |  7 ++++++-
 test/connection.test.js | 14 ++++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 4ae23003cd0..f87f943542b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -70,7 +70,12 @@ function Connection(base) {
   this._closeCalled = false;
   this._hasOpened = false;
   this.plugins = [];
-  this.id = id++;
+  // this.id = id++;
+  if (typeof base === 'undefined' || !base.connections.length) {
+    this.id = 0;
+  } else {
+    this.id = base.connections.length;
+  }
 }
 
 /*!
diff --git a/test/connection.test.js b/test/connection.test.js
index 26f6f64e071..1885921d68b 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1301,9 +1301,19 @@ describe('connections:', function() {
   });
   it('Connection id should be scoped per Mongoose Instance (gh-10025)', function() {
     const m = new mongoose.Mongoose;
-    console.log(m.connection.id);
+    // console.log('First Instance', m.connection.id); // should be x
+    const conn = m.createConnection();
+    // console.log(conn.id); // should be x + 1
     const m1 = new mongoose.Mongoose;
-    console.log(m1.connection.id);
+    // console.log('Second Instance', m1.connection.id); // should be y
+    const conn2 = m1.createConnection();
+    // console.log(conn2.id); // should be y + 1;
+    const conn3 = m.createConnection();
+    // console.log('Back to First Instance', conn3.id); // should be x + 2
+    assert.deepStrictEqual(m.connection.id, 0);
+    assert.deepStrictEqual(conn.id, m.connection.id + 1);
     assert.deepStrictEqual(m1.connection.id, 0);
+    assert.deepStrictEqual(conn2.id, m1.connection.id + 1);
+    assert.deepStrictEqual(conn3.id, m.connection.id + 2);
   });
 });

From 7a93c164af53144651a2eb740680976b2cc32d2d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 13:33:58 -0400
Subject: [PATCH 1834/2348] linter fix

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index f87f943542b..454b00eb59f 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -25,7 +25,7 @@ const parseConnectionString = require('mongodb/lib/core').parseConnectionString;
 const arrayAtomicsSymbol = require('./helpers/symbols').arrayAtomicsSymbol;
 const sessionNewDocuments = require('./helpers/symbols').sessionNewDocuments;
 
-let id = 0;
+// let id = 0;
 
 /*!
  * A list of authentication mechanisms that don't require a password for authentication.

From 391ececb508368b24b56ae23688f07fece1a5924 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 16:27:32 -0400
Subject: [PATCH 1835/2348] collation not added to text indexes

---
 lib/model.js               |  4 +---
 test/model.indexes.test.js | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 2b5fbb3b5f2..0b9819b90b3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1575,7 +1575,6 @@ function _ensureIndexes(model, options, callback) {
   let indexError;
 
   options = options || {};
-
   const done = function(err) {
     if (err && !model.$caught) {
       model.emit('error', err);
@@ -1635,7 +1634,6 @@ function _ensureIndexes(model, options, callback) {
     const indexFields = utils.clone(index[0]);
     const indexOptions = utils.clone(index[1]);
     delete indexOptions._autoIndex;
-
     _decorateDiscriminatorIndexOptions(model, indexOptions);
     if ('safe' in options) {
       _handleSafe(options);
@@ -1654,7 +1652,7 @@ function _ensureIndexes(model, options, callback) {
       indexOptions.background = options.background;
     }
     if (model.schema.options.hasOwnProperty('collation') &&
-        !indexOptions.hasOwnProperty('collation')) {
+        !indexOptions.hasOwnProperty('collation') && Object.values(indexFields) != 'text') {
       indexOptions.collation = model.schema.options.collation;
     }
 
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index d6d262bd91c..f47c3806249 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -666,5 +666,24 @@ describe('model', function() {
         ]);
       });
     });
+    it('should prevent collation on text indexes (gh-10044)', function() {
+      return co(function*() {
+        yield db.db.collection('User').drop().catch(() => {});
+
+        const userSchema = new mongoose.Schema({ username: String }, {
+          collation: {
+            locale: 'en',
+            strength: 2
+          }
+        });
+        userSchema.index({ username: 'text' }, { unique: true });
+        const User = db.model('User', userSchema, 'User');
+
+        yield User.init();
+        const indexes = yield User.listIndexes();
+        assert.ok(!indexes[1].collation);
+        yield User.collection.drop();
+      });
+    });
   });
 });

From c4897f9505da52054c6fe6c1281af5cdceed5bda Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 16:40:13 -0400
Subject: [PATCH 1836/2348] TIL Object.values in not supported on all browsers

---
 lib/model.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 0b9819b90b3..5ff590a4e15 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1633,6 +1633,9 @@ function _ensureIndexes(model, options, callback) {
 
     const indexFields = utils.clone(index[0]);
     const indexOptions = utils.clone(index[1]);
+    const textBlock = Object.keys(indexFields).map(function(key) {
+      return indexFields[key];
+    });
     delete indexOptions._autoIndex;
     _decorateDiscriminatorIndexOptions(model, indexOptions);
     if ('safe' in options) {
@@ -1652,7 +1655,7 @@ function _ensureIndexes(model, options, callback) {
       indexOptions.background = options.background;
     }
     if (model.schema.options.hasOwnProperty('collation') &&
-        !indexOptions.hasOwnProperty('collation') && Object.values(indexFields) != 'text') {
+        !indexOptions.hasOwnProperty('collation') && textBlock != 'text') {
       indexOptions.collation = model.schema.options.collation;
     }
 

From f231d7bb49439716e20b054120ad43182b3d8ca6 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 16:59:54 -0400
Subject: [PATCH 1837/2348] should work and is designed to handle multiple text
 fields

---
 lib/model.js | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 5ff590a4e15..26dd0ea674e 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1633,9 +1633,15 @@ function _ensureIndexes(model, options, callback) {
 
     const indexFields = utils.clone(index[0]);
     const indexOptions = utils.clone(index[1]);
-    const textBlock = Object.keys(indexFields).map(function(key) {
-      return indexFields[key];
-    });
+    const textBlock = () => {
+      const results = Object.keys(indexFields).map(function(key) {
+        return indexFields[key];
+      });
+      if (!results.includes('text')) {
+        return true;
+      }
+      return false;
+    };
     delete indexOptions._autoIndex;
     _decorateDiscriminatorIndexOptions(model, indexOptions);
     if ('safe' in options) {
@@ -1655,7 +1661,7 @@ function _ensureIndexes(model, options, callback) {
       indexOptions.background = options.background;
     }
     if (model.schema.options.hasOwnProperty('collation') &&
-        !indexOptions.hasOwnProperty('collation') && textBlock != 'text') {
+        !indexOptions.hasOwnProperty('collation') && textBlock()) {
       indexOptions.collation = model.schema.options.collation;
     }
 

From 4e74ea7ba11c8a5119c47123aba0fc950f652587 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 24 Mar 2021 17:14:26 -0400
Subject: [PATCH 1838/2348] TIL that includes() is also not supported in all
 browsers

---
 lib/model.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 26dd0ea674e..c3c69a255d6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1637,10 +1637,10 @@ function _ensureIndexes(model, options, callback) {
       const results = Object.keys(indexFields).map(function(key) {
         return indexFields[key];
       });
-      if (!results.includes('text')) {
-        return true;
+      if (results.indexOf('text') !== -1) {
+        return false;
       }
-      return false;
+      return true;
     };
     delete indexOptions._autoIndex;
     _decorateDiscriminatorIndexOptions(model, indexOptions);

From 6f0133aa3002d76eee5aaf82f9b7d25558883241 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 25 Mar 2021 11:16:54 -0400
Subject: [PATCH 1839/2348] removed comments

---
 lib/connection.js       | 3 ---
 test/connection.test.js | 5 -----
 2 files changed, 8 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 454b00eb59f..0c9f0d74eb8 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -25,8 +25,6 @@ const parseConnectionString = require('mongodb/lib/core').parseConnectionString;
 const arrayAtomicsSymbol = require('./helpers/symbols').arrayAtomicsSymbol;
 const sessionNewDocuments = require('./helpers/symbols').sessionNewDocuments;
 
-// let id = 0;
-
 /*!
  * A list of authentication mechanisms that don't require a password for authentication.
  * This is used by the authMechanismDoesNotRequirePassword method.
@@ -70,7 +68,6 @@ function Connection(base) {
   this._closeCalled = false;
   this._hasOpened = false;
   this.plugins = [];
-  // this.id = id++;
   if (typeof base === 'undefined' || !base.connections.length) {
     this.id = 0;
   } else {
diff --git a/test/connection.test.js b/test/connection.test.js
index 1885921d68b..e4119967df2 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -1301,15 +1301,10 @@ describe('connections:', function() {
   });
   it('Connection id should be scoped per Mongoose Instance (gh-10025)', function() {
     const m = new mongoose.Mongoose;
-    // console.log('First Instance', m.connection.id); // should be x
     const conn = m.createConnection();
-    // console.log(conn.id); // should be x + 1
     const m1 = new mongoose.Mongoose;
-    // console.log('Second Instance', m1.connection.id); // should be y
     const conn2 = m1.createConnection();
-    // console.log(conn2.id); // should be y + 1;
     const conn3 = m.createConnection();
-    // console.log('Back to First Instance', conn3.id); // should be x + 2
     assert.deepStrictEqual(m.connection.id, 0);
     assert.deepStrictEqual(conn.id, m.connection.id + 1);
     assert.deepStrictEqual(m1.connection.id, 0);

From c9bfb3061ba98232aaf9e665f8749dff3bac7db1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 25 Mar 2021 11:26:34 -0400
Subject: [PATCH 1840/2348] Update model.indexes.test.js

---
 test/model.indexes.test.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index f47c3806249..a0c339cdbae 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -668,8 +668,6 @@ describe('model', function() {
     });
     it('should prevent collation on text indexes (gh-10044)', function() {
       return co(function*() {
-        yield db.db.collection('User').drop().catch(() => {});
-
         const userSchema = new mongoose.Schema({ username: String }, {
           collation: {
             locale: 'en',

From 452c77ca4fcab6fe84ef0f13c5be9a45090b2c0d Mon Sep 17 00:00:00 2001
From: pezzu <7243796+pezzu@users.noreply.github.com>
Date: Mon, 29 Mar 2021 00:42:49 -0400
Subject: [PATCH 1841/2348] Fixes #10072

---
 index.d.ts                    |  4 ++--
 test/typescript/middleware.ts | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 77bd306b765..d539e0d8376 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1166,8 +1166,8 @@ declare module 'mongoose' {
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
+    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void): this;
+    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: { [name: string]: <T extends QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>> = QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index 7a89a3e34c0..45ca4c901dd 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -39,4 +39,27 @@ schema.post<ITest>('save', function(err: Error, res: ITest, next: Function) {
   console.log(this.name, err.stack);
 });
 
+schema.pre<Model<ITest>>('insertMany', function() {
+  return Promise.resolve(this.name);
+});
+
+schema.pre<Model<ITest>>('insertMany', { document: false, query: false }, function() {
+  console.log(this.name);
+});
+
+schema.pre<Model<ITest>>('insertMany', function(next) {
+  console.log(this.name);
+  next();
+});
+
+schema.pre<Model<ITest>>('insertMany', function(next, doc: ITest) {
+  console.log(this.name, doc);
+  next();
+});
+
+schema.pre<Model<ITest>>('insertMany', function(next, docs: Array<ITest>) {
+  console.log(this.name, docs);
+  next();
+});
+
 const Test = model<ITest>('Test', schema);

From d1a9a1e7bdb6fdecd43030d4241c092741be95bb Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 29 Mar 2021 11:07:59 -0400
Subject: [PATCH 1842/2348] made requested changes

---
 lib/model.js | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index c3c69a255d6..c653b694b64 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1633,12 +1633,11 @@ function _ensureIndexes(model, options, callback) {
 
     const indexFields = utils.clone(index[0]);
     const indexOptions = utils.clone(index[1]);
-    const textBlock = () => {
-      const results = Object.keys(indexFields).map(function(key) {
-        return indexFields[key];
-      });
-      if (results.indexOf('text') !== -1) {
-        return false;
+    const noText = () => {
+      for (const key in indexFields) {
+        if (indexFields[key] == 'text') {
+          return false;
+        }
       }
       return true;
     };
@@ -1661,7 +1660,7 @@ function _ensureIndexes(model, options, callback) {
       indexOptions.background = options.background;
     }
     if (model.schema.options.hasOwnProperty('collation') &&
-        !indexOptions.hasOwnProperty('collation') && textBlock()) {
+        !indexOptions.hasOwnProperty('collation') && noText()) {
       indexOptions.collation = model.schema.options.collation;
     }
 

From 7d2e9c9f930b182a2cf716851e1e2d9845a8a74c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 29 Mar 2021 11:09:40 -0400
Subject: [PATCH 1843/2348] chore: upgrade mquery -> 3.2.5 re:
 aheckmann/mquery#121

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 831487e8618..bcfbeb0af28 100644
--- a/package.json
+++ b/package.json
@@ -25,7 +25,7 @@
     "mongodb": "3.6.5",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
-    "mquery": "3.2.4",
+    "mquery": "3.2.5",
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.2.1",

From f24953c1a7c95c6f7f05309a961943da07572211 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 29 Mar 2021 21:53:05 -0400
Subject: [PATCH 1844/2348] fix(query): add `writeConcern()` method to avoid
 writeConcern deprecation warning

Fix #10009
---
 lib/query.js       | 47 ++++++++++++++++++++++++++++++++++++++++++++++
 test/query.test.js | 12 ++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/lib/query.js b/lib/query.js
index 86e2e627a22..8aa1bfeba5e 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1083,6 +1083,53 @@ Query.prototype.session = function session(v) {
   return this;
 };
 
+/**
+ * Sets the 3 write concern parameters for this query:
+ *
+ * - `w`: Sets the specified number of `mongod` servers, or tag set of `mongod` servers, that must acknowledge this write before this write is considered successful.
+ * - `j`: Boolean, set to `true` to request acknowledgement that this operation has been persisted to MongoDB's on-disk journal.
+ * - `wtimeout`: If [`w > 1`](/docs/api.html#query_Query-w), the maximum amount of time to wait for this write to propagate through the replica set before this operation fails. The default is `0`, which means no timeout.
+ *
+ * This option is only valid for operations that write to the database:
+ *
+ * - `deleteOne()`
+ * - `deleteMany()`
+ * - `findOneAndDelete()`
+ * - `findOneAndReplace()`
+ * - `findOneAndUpdate()`
+ * - `remove()`
+ * - `update()`
+ * - `updateOne()`
+ * - `updateMany()`
+ *
+ * Defaults to the schema's [`writeConcern` option](/docs/guide.html#writeConcern)
+ *
+ * ####Example:
+ *
+ *     // The 'majority' option means the `deleteOne()` promise won't resolve
+ *     // until the `deleteOne()` has propagated to the majority of the replica set
+ *     await mongoose.model('Person').
+ *       deleteOne({ name: 'Ned Stark' }).
+ *       writeConcern({ w: 'majority' });
+ *
+ * @method writeConcern
+ * @memberOf Query
+ * @instance
+ * @param {Object} writeConcern the write concern value to set
+ * @see mongodb https://mongodb.github.io/node-mongodb-native/3.1/api/global.html#WriteConcern
+ * @return {Query} this
+ * @api public
+ */
+
+Query.prototype.writeConcern = function writeConcern(val) {
+  if (val == null) {
+    delete this.options.writeConcern;
+    return this;
+  }
+  this.options.writeConcern = val;
+  return this;
+};
+
 /**
  * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
  * that must acknowledge this write before this write is considered successful.
diff --git a/test/query.test.js b/test/query.test.js
index e8cb49c9d17..ae121ad2b6d 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3776,4 +3776,16 @@ describe('Query', function() {
 
     assert.deepEqual(q._fields, { doesntpopulate: 0, populatescorrectly: 0 });
   });
+
+  it('sets `writeConcern` option correctly (gh-10009)', function() {
+    const testSchema = new mongoose.Schema({
+      name: String
+    });
+    const Test = db.model('Test', testSchema);
+
+    const q = Test.find();
+    q.writeConcern({ w: 'majority', wtimeout: 1000 });
+
+    assert.deepEqual(q.options.writeConcern, { w: 'majority', wtimeout: 1000 });
+  });
 });

From f3cd3a8898aa063487e04ede21a84e78247a2634 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 31 Mar 2021 12:04:05 -0400
Subject: [PATCH 1845/2348] chore: use variable instead of function

---
 lib/model.js | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index c653b694b64..13cb9832345 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1633,14 +1633,12 @@ function _ensureIndexes(model, options, callback) {
 
     const indexFields = utils.clone(index[0]);
     const indexOptions = utils.clone(index[1]);
-    const noText = () => {
-      for (const key in indexFields) {
-        if (indexFields[key] == 'text') {
-          return false;
-        }
+    let isTextIndex = false;
+    for (const key of Object.keys(indexFields)) {
+      if (indexFields[key] === 'text') {
+        isTextIndex = true;
       }
-      return true;
-    };
+    }
     delete indexOptions._autoIndex;
     _decorateDiscriminatorIndexOptions(model, indexOptions);
     if ('safe' in options) {
@@ -1660,7 +1658,8 @@ function _ensureIndexes(model, options, callback) {
       indexOptions.background = options.background;
     }
     if (model.schema.options.hasOwnProperty('collation') &&
-        !indexOptions.hasOwnProperty('collation') && noText()) {
+        !indexOptions.hasOwnProperty('collation')
+        !isTextIndex) {
       indexOptions.collation = model.schema.options.collation;
     }
 

From 9e4a0830107c8815e63ef7b11d8fa200f5ca51a6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 31 Mar 2021 12:05:46 -0400
Subject: [PATCH 1846/2348] style: fix lint

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 13cb9832345..d5d66d3aed8 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1658,7 +1658,7 @@ function _ensureIndexes(model, options, callback) {
       indexOptions.background = options.background;
     }
     if (model.schema.options.hasOwnProperty('collation') &&
-        !indexOptions.hasOwnProperty('collation')
+        !indexOptions.hasOwnProperty('collation') &&
         !isTextIndex) {
       indexOptions.collation = model.schema.options.collation;
     }

From 264808812831e36d181a862bfcdb96caef6b340f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 31 Mar 2021 13:08:44 -0400
Subject: [PATCH 1847/2348] fix(index.d.ts): add DocumentQuery type for
 backwards compatibility

Fix #10036
---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index d539e0d8376..31e43707499 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2715,6 +2715,8 @@ declare module 'mongoose' {
   /** Alias for QueryOptions for backwards compatability. */
   type ModelUpdateOptions = QueryOptions;
 
+  type DocumentQuery<ResultType, DocType extends Document, THelpers = {}> = Query<ResultType, DocType, THelpers>;
+
   /** Backwards support for DefinitelyTyped */
   interface HookSyncCallback<T> {
     (this: T, next: HookNextFunction, docs: any[]): Promise<any> | void;

From 538240887b642f024574c8ed1503420f2b20e920 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 31 Mar 2021 13:38:14 -0400
Subject: [PATCH 1848/2348] fix(index.d.ts): add `transform` to PopulateOptions
 interface

Fix #10061
---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 31e43707499..5bd3928a3df 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1036,6 +1036,8 @@ declare module 'mongoose' {
      * always set `path` to a document. Inferred from schema by default.
      */
     justOne?: boolean;
+    /** transform function to call on every populated doc */
+    transform?: (doc: any, id: any) => any;
   }
 
   interface ToObjectOptions {

From 58cad7334b7a833f7ac6dd7966b8ad86e2580b3a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 31 Mar 2021 13:54:54 -0400
Subject: [PATCH 1849/2348] fix(connection): use queueing instead of event
 emitter for `createCollection()` and other helpers to avoid event emitter
 warning

Fix #9778
---
 lib/connection.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 0c9f0d74eb8..8b6718da664 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -73,6 +73,7 @@ function Connection(base) {
   } else {
     this.id = base.connections.length;
   }
+  this._queue = [];
 }
 
 /*!
@@ -569,9 +570,7 @@ function _wrapConnHelper(fn) {
       // Re: gh-8534
       immediate(() => {
         if (this.readyState === STATES.connecting && this._shouldBufferCommands()) {
-          this.once('open', function() {
-            fn.apply(this, argsWithoutCb.concat([cb]));
-          });
+          this._queue.push({ fn: fn, ctx: this, args: argsWithoutCb.concat([cb]) });
         } else if (this.readyState === STATES.disconnected && this.db == null) {
           cb(disconnectedError);
         } else {
@@ -631,6 +630,11 @@ Connection.prototype.error = function(err, callback) {
 Connection.prototype.onOpen = function() {
   this.readyState = STATES.connected;
 
+  for (const d of this._queue) {
+    d.fn.apply(d.ctx, d.args);
+  }
+  this._queue = [];
+
   // avoid having the collection subscribe to our event emitter
   // to prevent 0.3 warning
   for (const i in this.collections) {

From f8d2721567ef3f0811cf591649e70bea20db68b4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 31 Mar 2021 14:25:37 -0400
Subject: [PATCH 1850/2348] chore: release 5.12.3

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index a209cb2ca60..cd3daf62008 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.12.3 / 2021-03-31
+===================
+ * fix: avoid setting schema-level collation on text indexes #10044 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(query): add `writeConcern()` method to avoid writeConcern deprecation warning #10009
+ * fix(connection): use queueing instead of event emitter for `createCollection()` and other helpers to avoid event emitter warning #9778
+ * fix(connection): scope `Connection#id` to Mongoose instance so id always lines up with `mongoose.connections` index #10025 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix: avoid throwing in `promiseOrCallback()` if 3rd param isn't an EventEmitter #10055 [emrebass](https://github.com/emrebass)
+ * fix(index.d.ts): add Model as 2nd generic param to `Model.discriminator()` #10054 [coro101](https://github.com/coro101)
+ * fix(index.d.ts): add docs to `next()` callback for `pre('insertMany')` hooks #10078 #10072 [pezzu](https://github.com/pezzu)
+ * fix(index.d.ts): add `transform` to PopulateOptions interface #10061
+ * fix(index.d.ts): add DocumentQuery type for backwards compatibility #10036
+
 5.12.2 / 2021-03-22
 ===================
  * fix(QueryCursor): consistently execute `post('find')` hooks with an array of docs #10015 #9982 [IslandRhythms](https://github.com/IslandRhythms)
diff --git a/package.json b/package.json
index bcfbeb0af28..a0808b8ebc1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.2",
+  "version": "5.12.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From bd9bcf14f9728cff92958f9905edf43f9f14cc41 Mon Sep 17 00:00:00 2001
From: Boris Figovsky <boris@hysolate.com>
Date: Fri, 2 Apr 2021 04:56:59 +0000
Subject: [PATCH 1851/2348] add missing asyncInterator to Query type def

---
 index.d.ts | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 5bd3928a3df..6b2ce82db0f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1850,6 +1850,13 @@ declare module 'mongoose' {
   class Query<ResultType, DocType extends Document, THelpers = {}> {
     _mongooseOptions: MongooseQueryOptions;
 
+    /**
+     * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
+     * A QueryCursor exposes a Streams3 interface, as well as a `.next()` function.
+     * This is equivalent to calling `.cursor()` with no arguments.
+     */
+    [Symbol.asyncIterator]: QueryCursor<DocType>;
+
     /** Executes the query */
     exec(): Promise<ResultType>;
     exec(callback?: (err: CallbackError, res: ResultType) => void): void;

From 658f02b5fe4ed3ece6518ff78e7c782ddd386552 Mon Sep 17 00:00:00 2001
From: Oleg N <75450326+olnazx@users.noreply.github.com>
Date: Fri, 2 Apr 2021 17:18:50 +0300
Subject: [PATCH 1852/2348] fix(model): filter out all not actually inserted
 docs from `insertedDocs` when using `insertMany()` with `ordered = true`

---
 lib/model.js       | 18 +++++++++++++++++-
 test/model.test.js | 25 +++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index d5d66d3aed8..8565ad6864b 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3343,8 +3343,24 @@ Model.$__insertMany = function(arr, options, callback) {
 
         // `insertedDocs` is a Mongoose-specific property
         const erroredIndexes = new Set(get(error, 'writeErrors', []).map(err => err.index));
+
+        let firstErroredIndex = -1;
         error.insertedDocs = docAttributes.
-          filter((doc, i) => !erroredIndexes.has(i)).
+          filter((doc, i) => {
+            const isErrored = erroredIndexes.has(i);
+
+            if (ordered) {
+              if (firstErroredIndex > -1) {
+                return i < firstErroredIndex;
+              }
+
+              if (isErrored) {
+                firstErroredIndex = i;
+              }
+            }
+
+            return !isErrored;
+          }).
           map(function setIsNewForInsertedDoc(doc) {
             doc.$__reset();
             _setIsNew(doc, false);
diff --git a/test/model.test.js b/test/model.test.js
index 596f66d91e6..70cb026e598 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -4774,6 +4774,31 @@ describe('Model', function() {
       });
     });
 
+    it('insertMany() returns only inserted docs with `ordered = true`', function() {
+      const schema = new Schema({
+        name: { type: String, required: true, unique: true }
+      });
+      const Movie = db.model('Movie', schema);
+
+      const arr = [
+        { name: 'The Phantom Menace' },
+        { name: 'The Empire Strikes Back' },
+        { name: 'The Phantom Menace' },
+        { name: 'Jingle All The Way' }
+      ];
+      const opts = { ordered: true };
+      return co(function*() {
+        yield Movie.init();
+        const err = yield Movie.insertMany(arr, opts).then(() => err, err => err);
+        assert.ok(err);
+        assert.ok(err.insertedDocs);
+
+        assert.equal(err.insertedDocs.length, 2);
+        assert.strictEqual(err.insertedDocs[0].name, 'The Phantom Menace');
+        assert.strictEqual(err.insertedDocs[1].name, 'The Empire Strikes Back');
+      });
+    });
+
     it('insertMany() validation error with ordered true and rawResult true when all documents are invalid', function(done) {
       const schema = new Schema({
         name: { type: String, required: true }

From 952d5de7267614b5981a92c8ffab0dad02918bfc Mon Sep 17 00:00:00 2001
From: ptantiku <ptantiku@gmail.com>
Date: Sat, 3 Apr 2021 03:48:45 +0700
Subject: [PATCH 1853/2348] fixes #10100 by update default
 internalToObjectOptions in /lib/options.js

---
 lib/options.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/options.js b/lib/options.js
index 8e9fc2941ef..2ae69f7a3a0 100644
--- a/lib/options.js
+++ b/lib/options.js
@@ -10,5 +10,6 @@ exports.internalToObjectOptions = {
   getters: false,
   _skipDepopulateTopLevel: true,
   depopulate: true,
-  flattenDecimals: false
+  flattenDecimals: false,
+  useProjection: false,
 };

From 70e31911d26cbaf70d5da8e669f594711080227e Mon Sep 17 00:00:00 2001
From: ptantiku <ptantiku@gmail.com>
Date: Sat, 3 Apr 2021 04:15:58 +0700
Subject: [PATCH 1854/2348] style: fix lint

---
 lib/options.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/options.js b/lib/options.js
index 2ae69f7a3a0..4826e59fdc5 100644
--- a/lib/options.js
+++ b/lib/options.js
@@ -11,5 +11,5 @@ exports.internalToObjectOptions = {
   _skipDepopulateTopLevel: true,
   depopulate: true,
   flattenDecimals: false,
-  useProjection: false,
+  useProjection: false
 };

From 0a361822261ffaf0f03c061e339f2ed91f050d4a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 5 Apr 2021 18:00:37 -0400
Subject: [PATCH 1855/2348] added test

---
 lib/model.js                |  2 -
 lib/query.js                |  1 -
 test/model.populate.test.js | 78 +++++++++++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index d5d66d3aed8..594f4ddc016 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4311,7 +4311,6 @@ Model.populate = function(docs, paths, callback) {
 
 function _populate(model, docs, paths, cache, callback) {
   let pending = paths.length;
-
   if (paths.length === 0) {
     return callback(null, docs);
   }
@@ -4434,7 +4433,6 @@ function populate(model, docs, options, callback) {
     }
     params.push([mod, match, select, assignmentOpts, _next]);
   }
-
   if (!hasOne) {
     // If no models to populate but we have a nested populate,
     // keep trying, re: gh-8946
diff --git a/lib/query.js b/lib/query.js
index 8aa1bfeba5e..b61456d8557 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4768,7 +4768,6 @@ Query.prototype.populate = function() {
 
     pop[populateOptions.path] = populateOptions;
   }
-
   return this;
 };
 
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a5cea0a105c..64631a2fde5 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10200,4 +10200,82 @@ describe('model: populate:', function() {
       assert.equal(modelA1._modelB._rootModel.name, 'my name');
     });
   });
+  it('prevents already populated fields from becoming null gh-10068', function() {
+    return co(function*() {
+      const Books = db.model('books', new Schema({name: String, contributors: [{author: Schema.Types.ObjectId}]}))
+      const Authors = db.model('authors', new Schema({name: String}))
+
+      const anAuthor = new Authors({name: 'Author1'})
+      yield anAuthor.save()
+
+      const aBook1 = new Books({name: 'Book1', contributors: [{author: anAuthor.id}]})
+      yield aBook1.save()
+      const aBook2 = new Books({name: 'Book2', contributors: [{author: anAuthor.id}]})
+      yield aBook2.save()
+
+      const populateOptions = [{
+              path: 'contributors.author', //*Note the array of objects - regular objects work as expected
+              model: 'authors',
+              select: '_id name'
+          }
+      ]
+
+      //Get the books and make book2 author in contributors just an id instead of an object
+      const populatedBooks = (yield Books.find().populate(populateOptions)).map(aBook => {
+          aBook = aBook.toObject()
+          if (!aBook._id.equals(aBook1.id)) {
+              aBook.contributors[0].author = aBook.contributors[0].author._id
+          }
+          return aBook
+      });
+
+      //console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true))
+      //after population and some manipulation, populatedBooks array:
+      /*const populatedBooks = [{
+          _id: aBook1.id,
+          name: aBook1.name
+          contributors: [{
+              _id: ObjectId
+              author: {
+                  _id: anAuthor.id,
+                  name: anAuthor.name
+              }
+          }]
+      }, {
+          _id: aBook2.id,
+          name: aBook2.name
+          contributors: [{
+              _id: ObjectId
+              author: anAuthor.id
+          }]
+      }]
+      */
+
+      //now, we try to populate the array to get the remaining author that was not previously populated for aBook2
+      const populatedBooksAgain = yield Books.populate(populatedBooks, populateOptions);
+      //console.log('populatedBooksAgain = ' + util.inspect(populatedBooks, false, null, true))
+
+      //after population, populatedBooksAgain array:
+      /*const populatedBooksAgain = [{
+          _id: aBook1.id,
+          name: aBook1.name
+          contributors: [{
+              _id: ObjectId
+              author: null //*this should NOT be null - it should be the same object going into populate (and it was in 5.2.10)
+          }]
+      }, {
+          _id: aBook2.id,
+          name: aBook2.name
+          contributors: [{
+              _id: ObjectId
+              author: {
+                  _id: anAuthor.id, 
+                  name: anAuthor.name
+              }
+          }]
+      }]
+      */
+      !assert.equal(populatedBooksAgain[0].contributors[0].author, 'null');
+    });
+  });
 });

From 613e424463bde001d6901d4d312080e4b3d63150 Mon Sep 17 00:00:00 2001
From: LoneRifle <alwyn.tan@gmail.com>
Date: Tue, 6 Apr 2021 09:02:21 +0000
Subject: [PATCH 1856/2348] refactor(index.d.ts): move `discriminator()` to
 common interface

To ensure consistency in `discriminator()` declarations across
Model, Array and DocumentArray, create a common interface that
has the declarations found in Model, and have the other two classes
implement the interface

- Move `Model.discriminator()` declarations to AcceptsDiscriminator
- Adjust the declarations so that both accept a Schema with at least
  the type argument for Document
- Implement AcceptsDiscriminator in Array and DocumentArray by copying
  the method declarations into the respective class declarations
---
 index.d.ts | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 5bd3928a3df..b12fb4b26b7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -598,9 +598,15 @@ declare module 'mongoose' {
     validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
   }
 
+  interface AcceptsDiscriminator {
+    /** Adds a discriminator type. */
+    discriminator<D extends Document>(name: string, schema: Schema<D>, value?: string): Model<D>;
+    discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
+  }
+
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter {
+  interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
     new(doc?: any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
@@ -780,10 +786,6 @@ declare module 'mongoose' {
     /** Translate any aliases fields/conditions so the final query or document object is pure */
     translateAliases(raw: any): any;
 
-    /** Adds a discriminator type. */
-    discriminator<D extends Document>(name: string, schema: Schema, value?: string): Model<D>;
-    discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
-
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, T, TQueryHelpers>;
 
@@ -1596,13 +1598,14 @@ declare module 'mongoose' {
 
   namespace Schema {
     namespace Types {
-      class Array extends SchemaType {
+      class Array extends SchemaType implements AcceptsDiscriminator {
         /** This schema type's name, to defend against minifiers that mangle function names. */
         static schemaName: string;
 
         static options: { castNonArrays: boolean; };
 
-        discriminator(name: string, schema: Schema, tag?: string): any;
+        discriminator<D extends Document>(name: string, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
 
         /**
          * Adds an enum validator if this is an array of strings or numbers. Equivalent to
@@ -1652,13 +1655,14 @@ declare module 'mongoose' {
         static schemaName: string;
       }
 
-      class DocumentArray extends SchemaType {
+      class DocumentArray extends SchemaType implements AcceptsDiscriminator {
         /** This schema type's name, to defend against minifiers that mangle function names. */
         static schemaName: string;
 
         static options: { castNonArrays: boolean; };
 
-        discriminator(name: string, schema: Schema, tag?: string): any;
+        discriminator<D extends Document>(name: string, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
 
         /** The schema used for documents in this array */
         schema: Schema;

From b7518a3ecf361e440fe4b968cf33e592a9c55959 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 6 Apr 2021 12:54:38 -0400
Subject: [PATCH 1857/2348] added logs

---
 lib/helpers/populate/assignVals.js | 10 ++++++++--
 lib/model.js                       | 14 +++++++-------
 test/model.populate.test.js        |  3 ++-
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 2cbe3939cc6..051669a0db1 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -18,6 +18,9 @@ module.exports = function assignVals(o) {
   const populateOptions = Object.assign({}, o.options, userOptions, {
     justOne: o.justOne
   });
+  //console.log('o', o);
+  //console.log('user', userOptions);
+  //console.log('pop',populateOptions);
   populateOptions.$nullIfNotFound = o.isVirtual;
   const populatedModel = o.populatedModel;
 
@@ -34,7 +37,6 @@ module.exports = function assignVals(o) {
   const rawIds = o.rawIds;
   const options = o.options;
   const count = o.count && o.isVirtual;
-
   let i;
 
   function setValue(val) {
@@ -70,6 +72,7 @@ module.exports = function assignVals(o) {
     } else if (o.justOne === false && !Array.isArray(val)) {
       return valueFilter([val], options, populateOptions, _allIds);
     }
+    console.log('last executed line of setValue');
     return valueFilter(val, options, populateOptions, _allIds);
   }
 
@@ -166,7 +169,8 @@ module.exports = function assignVals(o) {
     // If lean, need to check that each individual virtual respects
     // `justOne`, because you may have a populated virtual with `justOne`
     // underneath an array. See gh-6867
-    mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
+    console.log('last line of assignVals');
+    return mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
   }
 };
 
@@ -236,6 +240,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
 
   // findOne
   if (isPopulatedObject(val)) {
+    console.log('1st');
     maybeRemoveId(val, assignmentOpts);
     return transform(val, allIds);
   }
@@ -245,6 +250,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   }
 
   if (populateOptions.justOne === true) {
+    console.log('2nd');
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }
   if (populateOptions.justOne === false) {
diff --git a/lib/model.js b/lib/model.js
index 594f4ddc016..8cc9da2ea93 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4291,7 +4291,6 @@ Model.populate = function(docs, paths, callback) {
   const cache = {};
 
   callback = this.$handleCallbackError(callback);
-
   return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
     _populate(_this, docs, paths, cache, cb);
@@ -4327,7 +4326,7 @@ function _populate(model, docs, paths, cache, callback) {
     if (--pending) {
       return;
     }
-    callback(null, docs);
+    return callback(null, docs);
   }
 }
 
@@ -4342,7 +4341,6 @@ function populate(model, docs, options, callback) {
   if (!Array.isArray(docs)) {
     docs = [docs];
   }
-
   if (docs.length === 0 || docs.every(utils.isNullOrUndefined)) {
     return callback();
   }
@@ -4369,7 +4367,6 @@ function populate(model, docs, options, callback) {
     const mod = modelsMap[i];
     let select = mod.options.select;
     const match = _formatMatch(mod.match);
-
     let ids = utils.array.flatten(mod.ids, flatten);
     ids = utils.array.unique(ids);
 
@@ -4473,6 +4470,7 @@ function populate(model, docs, options, callback) {
     }
     callback();
   }
+  console.log('last line of populate')
 }
 
 /*!
@@ -4552,8 +4550,7 @@ function _assign(model, vals, mod, assignmentOpts) {
   let val;
 
   // Clone because `assignRawDocsToIdStructure` will mutate the array
-  const allIds = utils.clone(mod.allIds);
-
+  let allIds = utils.clone(mod.allIds);
   // optimization:
   // record the document positions as returned by
   // the query result.
@@ -4619,12 +4616,15 @@ function _assign(model, vals, mod, assignmentOpts) {
       }
     }
   }
-
+  //console.log('rawdocs',rawDocs);
+  //console.log('Ids', allIds);
+  //console.log('modIds', mod.allIds);
   assignVals({
     originalModel: model,
     // If virtual, make sure to not mutate original field
     rawIds: mod.isVirtual ? allIds : mod.allIds,
     allIds: allIds,
+    localField: mod.localField,
     foreignField: mod.foreignField,
     rawDocs: rawDocs,
     rawOrder: rawOrder,
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 64631a2fde5..7776dbefe8d 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10275,7 +10275,8 @@ describe('model: populate:', function() {
           }]
       }]
       */
-      !assert.equal(populatedBooksAgain[0].contributors[0].author, 'null');
+     console.log('hi', populatedBooksAgain[0].contributors[0].author);
+      assert.equal(populatedBooksAgain[0].contributors[0].author, 'Author1');
     });
   });
 });

From 8a46448942363a89d6098f530a14cb604db96055 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 6 Apr 2021 17:20:23 -0400
Subject: [PATCH 1858/2348] Update lookupLocalFields.js

---
 lib/helpers/populate/lookupLocalFields.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/helpers/populate/lookupLocalFields.js b/lib/helpers/populate/lookupLocalFields.js
index 08ed7632015..fd925419b56 100644
--- a/lib/helpers/populate/lookupLocalFields.js
+++ b/lib/helpers/populate/lookupLocalFields.js
@@ -21,6 +21,5 @@ module.exports = function lookupLocalFields(cur, path, val) {
       Array.from(cur.values()) :
       Object.keys(cur).map(key => cur[key]);
   }
-
   return cur[path];
 };
\ No newline at end of file

From 978546de396ef40fd96f3f86ace0b0e9780eee20 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 7 Apr 2021 13:39:32 -0400
Subject: [PATCH 1859/2348] update

---
 lib/helpers/populate/assignVals.js | 11 ++---------
 lib/model.js                       |  8 ++------
 test/model.populate.test.js        |  6 +++---
 3 files changed, 7 insertions(+), 18 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 051669a0db1..615f3358a99 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -9,6 +9,7 @@ const lookupLocalFields = require('./lookupLocalFields');
 const mpath = require('mpath');
 const sift = require('sift').default;
 const utils = require('../../utils');
+const cleanPositionalOperators = require('../schema/cleanPositionalOperators');
 
 module.exports = function assignVals(o) {
   // Options that aren't explicitly listed in `populateOptions`
@@ -18,9 +19,6 @@ module.exports = function assignVals(o) {
   const populateOptions = Object.assign({}, o.options, userOptions, {
     justOne: o.justOne
   });
-  //console.log('o', o);
-  //console.log('user', userOptions);
-  //console.log('pop',populateOptions);
   populateOptions.$nullIfNotFound = o.isVirtual;
   const populatedModel = o.populatedModel;
 
@@ -72,7 +70,6 @@ module.exports = function assignVals(o) {
     } else if (o.justOne === false && !Array.isArray(val)) {
       return valueFilter([val], options, populateOptions, _allIds);
     }
-    console.log('last executed line of setValue');
     return valueFilter(val, options, populateOptions, _allIds);
   }
 
@@ -169,7 +166,6 @@ module.exports = function assignVals(o) {
     // If lean, need to check that each individual virtual respects
     // `justOne`, because you may have a populated virtual with `justOne`
     // underneath an array. See gh-6867
-    console.log('last line of assignVals');
     return mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
   }
 };
@@ -240,7 +236,6 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
 
   // findOne
   if (isPopulatedObject(val)) {
-    console.log('1st');
     maybeRemoveId(val, assignmentOpts);
     return transform(val, allIds);
   }
@@ -248,9 +243,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (val instanceof Map) {
     return val;
   }
-
   if (populateOptions.justOne === true) {
-    console.log('2nd');
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }
   if (populateOptions.justOne === false) {
@@ -282,7 +275,7 @@ function isPopulatedObject(obj) {
   if (obj == null) {
     return false;
   }
-
+  //need to add new or statement
   return Array.isArray(obj) ||
     obj.$isMongooseMap ||
     obj.$__ != null ||
diff --git a/lib/model.js b/lib/model.js
index 8cc9da2ea93..ac731411db4 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4326,7 +4326,7 @@ function _populate(model, docs, paths, cache, callback) {
     if (--pending) {
       return;
     }
-    return callback(null, docs);
+    callback(null, docs);
   }
 }
 
@@ -4470,7 +4470,6 @@ function populate(model, docs, options, callback) {
     }
     callback();
   }
-  console.log('last line of populate')
 }
 
 /*!
@@ -4616,15 +4615,12 @@ function _assign(model, vals, mod, assignmentOpts) {
       }
     }
   }
-  //console.log('rawdocs',rawDocs);
-  //console.log('Ids', allIds);
-  //console.log('modIds', mod.allIds);
+
   assignVals({
     originalModel: model,
     // If virtual, make sure to not mutate original field
     rawIds: mod.isVirtual ? allIds : mod.allIds,
     allIds: allIds,
-    localField: mod.localField,
     foreignField: mod.foreignField,
     rawDocs: rawDocs,
     rawOrder: rawOrder,
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 7776dbefe8d..3c1785bd812 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10250,7 +10250,7 @@ describe('model: populate:', function() {
           }]
       }]
       */
-
+      console.log('hi 1st', populatedBooks[0].contributors[0].author);
       //now, we try to populate the array to get the remaining author that was not previously populated for aBook2
       const populatedBooksAgain = yield Books.populate(populatedBooks, populateOptions);
       //console.log('populatedBooksAgain = ' + util.inspect(populatedBooks, false, null, true))
@@ -10275,8 +10275,8 @@ describe('model: populate:', function() {
           }]
       }]
       */
-     console.log('hi', populatedBooksAgain[0].contributors[0].author);
-      assert.equal(populatedBooksAgain[0].contributors[0].author, 'Author1');
+     console.log('hi 2nd', populatedBooksAgain[0].contributors[0].author);
+      assert.equal(populatedBooksAgain[0].contributors[0].author.name, 'Author1');
     });
   });
 });

From f561cc0f7b6069adb864e852d389a9e66831823a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 7 Apr 2021 14:04:22 -0400
Subject: [PATCH 1860/2348] Update assignVals.js

---
 lib/helpers/populate/assignVals.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 615f3358a99..7a019887e86 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -275,6 +275,7 @@ function isPopulatedObject(obj) {
   if (obj == null) {
     return false;
   }
+  //if(typeof obj.$__ == 'undefined') return true;
   //need to add new or statement
   return Array.isArray(obj) ||
     obj.$isMongooseMap ||

From 2927877f3808b7d1d367ccf9bf49b4cb950123fa Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 7 Apr 2021 14:08:20 -0400
Subject: [PATCH 1861/2348] Update assignVals.js

---
 lib/helpers/populate/assignVals.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 7a019887e86..1ccdfdd639c 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -233,7 +233,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
     }
     return val;
   }
-
+  // console.log(populateOptions);
   // findOne
   if (isPopulatedObject(val)) {
     maybeRemoveId(val, assignmentOpts);
@@ -243,6 +243,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (val instanceof Map) {
     return val;
   }
+  // if(typeof populateOptions._queryProjection === 'undefined') return transform(val, allIds)
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }

From fd2579a694e23dc2b361095c698b574b00c8da8d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 8 Apr 2021 16:17:42 -0400
Subject: [PATCH 1862/2348] fix: prevents populated fields from becoming null

---
 lib/helpers/populate/assignVals.js | 8 +++++---
 test/model.populate.test.js        | 2 --
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 1ccdfdd639c..ee19677cc4c 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -9,7 +9,6 @@ const lookupLocalFields = require('./lookupLocalFields');
 const mpath = require('mpath');
 const sift = require('sift').default;
 const utils = require('../../utils');
-const cleanPositionalOperators = require('../schema/cleanPositionalOperators');
 
 module.exports = function assignVals(o) {
   // Options that aren't explicitly listed in `populateOptions`
@@ -233,7 +232,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
     }
     return val;
   }
-  // console.log(populateOptions);
+
   // findOne
   if (isPopulatedObject(val)) {
     maybeRemoveId(val, assignmentOpts);
@@ -243,7 +242,10 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (val instanceof Map) {
     return val;
   }
-  // if(typeof populateOptions._queryProjection === 'undefined') return transform(val, allIds)
+  if (typeof populateOptions._queryProjection === 'undefined') {
+    return transform(val, allIds);
+  }
+
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 3c1785bd812..7b76a6f250a 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10250,7 +10250,6 @@ describe('model: populate:', function() {
           }]
       }]
       */
-      console.log('hi 1st', populatedBooks[0].contributors[0].author);
       //now, we try to populate the array to get the remaining author that was not previously populated for aBook2
       const populatedBooksAgain = yield Books.populate(populatedBooks, populateOptions);
       //console.log('populatedBooksAgain = ' + util.inspect(populatedBooks, false, null, true))
@@ -10275,7 +10274,6 @@ describe('model: populate:', function() {
           }]
       }]
       */
-     console.log('hi 2nd', populatedBooksAgain[0].contributors[0].author);
       assert.equal(populatedBooksAgain[0].contributors[0].author.name, 'Author1');
     });
   });

From 48f4605dad560c4a58f2156014eb7aa7ba8d849e Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 8 Apr 2021 17:36:14 -0400
Subject: [PATCH 1863/2348] linter fixes

---
 test/model.populate.test.js | 50 ++++++++++++++++++-------------------
 1 file changed, 25 insertions(+), 25 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 7b76a6f250a..d225ac66432 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10202,36 +10202,36 @@ describe('model: populate:', function() {
   });
   it('prevents already populated fields from becoming null gh-10068', function() {
     return co(function*() {
-      const Books = db.model('books', new Schema({name: String, contributors: [{author: Schema.Types.ObjectId}]}))
-      const Authors = db.model('authors', new Schema({name: String}))
+      const Books = db.model('books', new Schema({ name: String, contributors: [{ author: Schema.Types.ObjectId} ] }));
+      const Authors = db.model('authors', new Schema({name: String}));
 
-      const anAuthor = new Authors({name: 'Author1'})
-      yield anAuthor.save()
+      const anAuthor = new Authors({name: 'Author1'});
+      yield anAuthor.save();
 
-      const aBook1 = new Books({name: 'Book1', contributors: [{author: anAuthor.id}]})
-      yield aBook1.save()
-      const aBook2 = new Books({name: 'Book2', contributors: [{author: anAuthor.id}]})
-      yield aBook2.save()
+      const aBook1 = new Books({ name: 'Book1', contributors: [{ author: anAuthor.id }] });
+      yield aBook1.save();
+      const aBook2 = new Books({ name: 'Book2', contributors: [{ author: anAuthor.id }] });
+      yield aBook2.save();
 
       const populateOptions = [{
-              path: 'contributors.author', //*Note the array of objects - regular objects work as expected
-              model: 'authors',
-              select: '_id name'
-          }
-      ]
+        path: 'contributors.author', // *Note the array of objects - regular objects work as expected
+        model: 'authors',
+        select: '_id name'
+        }
+      ];
 
-      //Get the books and make book2 author in contributors just an id instead of an object
+      // Get the books and make book2 author in contributors just an id instead of an object
       const populatedBooks = (yield Books.find().populate(populateOptions)).map(aBook => {
-          aBook = aBook.toObject()
+          aBook = aBook.toObject();
           if (!aBook._id.equals(aBook1.id)) {
-              aBook.contributors[0].author = aBook.contributors[0].author._id
+              aBook.contributors[0].author = aBook.contributors[0].author._id;
           }
-          return aBook
+          return aBook;
       });
 
-      //console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true))
-      //after population and some manipulation, populatedBooks array:
-      /*const populatedBooks = [{
+      // console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true))
+      // after population and some manipulation, populatedBooks array:
+      /* const populatedBooks = [{
           _id: aBook1.id,
           name: aBook1.name
           contributors: [{
@@ -10250,12 +10250,12 @@ describe('model: populate:', function() {
           }]
       }]
       */
-      //now, we try to populate the array to get the remaining author that was not previously populated for aBook2
+      // now, we try to populate the array to get the remaining author that was not previously populated for aBook2
       const populatedBooksAgain = yield Books.populate(populatedBooks, populateOptions);
-      //console.log('populatedBooksAgain = ' + util.inspect(populatedBooks, false, null, true))
+      // console.log('populatedBooksAgain = ' + util.inspect(populatedBooks, false, null, true))
 
-      //after population, populatedBooksAgain array:
-      /*const populatedBooksAgain = [{
+      // after population, populatedBooksAgain array:
+      /* const populatedBooksAgain = [{
           _id: aBook1.id,
           name: aBook1.name
           contributors: [{
@@ -10268,7 +10268,7 @@ describe('model: populate:', function() {
           contributors: [{
               _id: ObjectId
               author: {
-                  _id: anAuthor.id, 
+                  _id: anAuthor.id,
                   name: anAuthor.name
               }
           }]

From 5df3ae8d166071936ef0de60183fa9f0146dcb5b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 8 Apr 2021 17:44:19 -0400
Subject: [PATCH 1864/2348] more linter fixes

---
 test/model.populate.test.js | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index d225ac66432..f326f62a69f 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10202,10 +10202,10 @@ describe('model: populate:', function() {
   });
   it('prevents already populated fields from becoming null gh-10068', function() {
     return co(function*() {
-      const Books = db.model('books', new Schema({ name: String, contributors: [{ author: Schema.Types.ObjectId} ] }));
-      const Authors = db.model('authors', new Schema({name: String}));
+      const Books = db.model('books', new Schema({ name: String, contributors: [{ author: Schema.Types.ObjectId }] }));
+      const Authors = db.model('authors', new Schema({ name: String }));
 
-      const anAuthor = new Authors({name: 'Author1'});
+      const anAuthor = new Authors({ name: 'Author1' });
       yield anAuthor.save();
 
       const aBook1 = new Books({ name: 'Book1', contributors: [{ author: anAuthor.id }] });
@@ -10217,16 +10217,15 @@ describe('model: populate:', function() {
         path: 'contributors.author', // *Note the array of objects - regular objects work as expected
         model: 'authors',
         select: '_id name'
-        }
-      ];
+      }];
 
       // Get the books and make book2 author in contributors just an id instead of an object
       const populatedBooks = (yield Books.find().populate(populateOptions)).map(aBook => {
-          aBook = aBook.toObject();
-          if (!aBook._id.equals(aBook1.id)) {
-              aBook.contributors[0].author = aBook.contributors[0].author._id;
-          }
-          return aBook;
+        aBook = aBook.toObject();
+        if (!aBook._id.equals(aBook1.id)) {
+          aBook.contributors[0].author = aBook.contributors[0].author._id;
+        }
+        return aBook;
       });
 
       // console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true))

From 458949e49005b3adbe1ab77ceb88e18faaa2c568 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 8 Apr 2021 17:51:17 -0400
Subject: [PATCH 1865/2348] linter fix

---
 lib/helpers/populate/assignVals.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index ee19677cc4c..5c037543005 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -278,8 +278,8 @@ function isPopulatedObject(obj) {
   if (obj == null) {
     return false;
   }
-  //if(typeof obj.$__ == 'undefined') return true;
-  //need to add new or statement
+  // if(typeof obj.$__ == 'undefined') return true;
+  // need to add new or statement
   return Array.isArray(obj) ||
     obj.$isMongooseMap ||
     obj.$__ != null ||

From fdf3bf63d520b36008e66fd16136fcfc672ef3ce Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 8 Apr 2021 18:00:32 -0400
Subject: [PATCH 1866/2348] Update assignVals.js

---
 lib/helpers/populate/assignVals.js | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 5c037543005..0fa78c52af6 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -242,13 +242,11 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (val instanceof Map) {
     return val;
   }
-  if (typeof populateOptions._queryProjection === 'undefined') {
-    return transform(val, allIds);
-  }
 
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }
+
   if (populateOptions.justOne === false) {
     return [];
   }

From 293afcb5bfcb57b551655140bb5662f0b9d15bff Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 8 Apr 2021 18:06:46 -0400
Subject: [PATCH 1867/2348] unrelated test failures so not sure if this works

---
 lib/helpers/populate/assignVals.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 0fa78c52af6..3e11cbb1fe7 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -243,6 +243,10 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
     return val;
   }
 
+  if (typeof populateOptions._queryProjection === 'undefined') {
+    return transform(val, allIds);
+  }
+
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }

From 7b841e5ce0e225fda6f61cd5929ff4f81ec213e0 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 10 Apr 2021 10:34:18 +0200
Subject: [PATCH 1868/2348] feature(model): add more to Model.bulkSave(...)

---
 lib/model.js       |  53 ++++++++++++++++++-
 test/model.test.js | 124 ++++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 168 insertions(+), 9 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index f14e47256c7..a7463b3c416 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3526,10 +3526,59 @@ Model.bulkWrite = function(ops, options, callback) {
 Model.bulkSave = function(documents) {
   const writeOperations = this.buildBulkWriteOperations(documents);
 
-  // err.writeErrors.map(documentError=>documentError.err.op.q._id)
-  return this.bulkWrite(writeOperations);
+  const preSavePromises = documents.map((document) => {
+    return new Promise((resolve, reject) => {
+      document.schema.s.hooks.execPre('save', document, (err) => {
+        if (err) {
+          reject(err);
+          return;
+        }
+        resolve();
+      });
+    });
+  });
+
+  let bulkWriteResultPromise;
+  return Promise.all(preSavePromises)
+    .then(() => bulkWriteResultPromise = this.bulkWrite(writeOperations))
+    .then(() => documents.map(buildSuccessfulWriteHandlerPromise))
+    .then(() => bulkWriteResultPromise)
+    .catch((err) => {
+      if (!get(err, 'writeErrors.length')) {
+        throw err;
+      }
+      return Promise.all(
+        documents.map((document) => {
+          const documentError = err.writeErrors.find(writeError => {
+            const writeErrorDocumentId = writeError.err.op._id || writeError.err.op.q._id;
+            return writeErrorDocumentId.toString() === document._id.toString();
+          });
+
+          if (documentError == null) {
+            return buildSuccessfulWriteHandlerPromise(document);
+          }
+        })
+      ).then(() => {
+        throw err;
+      });
+    });
 };
 
+function buildSuccessfulWriteHandlerPromise(document) {
+  return new Promise((resolve, reject) => {
+    handleSuccessfulWrite(document, resolve, reject);
+  });
+}
+
+function handleSuccessfulWrite(document, resolve) {
+  if (document.isNew) {
+    _setIsNew(document, false);
+  }
+  resolve();
+  document.$__reset();
+}
+
+
 Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents) {
   if (!Array.isArray(documents)) {
     throw new Error(`bulkSave expects an array of documents to be passed, received \`${documents}\` instead`);
diff --git a/test/model.test.js b/test/model.test.js
index aa8ca80c8c1..39bfbc56cc8 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7237,7 +7237,7 @@ describe('Model', function() {
       });
     });
 
-    it('returns writeResult on success, err is null', () => {
+    it('returns writeResult on success', () => {
       return co(function* () {
         const userSchema = new Schema({
           name: { type: String }
@@ -7257,10 +7257,10 @@ describe('Model', function() {
         users[1].name = 'Hafez2_gh-9673-2-updated';
 
         const writeResult = yield User.bulkSave(users);
-        assert.ok(writeResult);
+        assert.ok(writeResult.result.ok);
       });
     });
-    it('returns err on failure, writeResult is null', () => {
+    it('throws an error on failure', () => {
       return co(function* () {
         const userSchema = new Schema({
           name: { type: String, unique: true }
@@ -7283,8 +7283,118 @@ describe('Model', function() {
         assert.ok(err);
       });
     });
-    it('throws an error when a document throws a unique error');
-    it('changes document state from `isNew` `false` to `true`');
-    it('changes documents state');
+    it('changes document state from `isNew` `false` to `true`', () => {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String }
+        });
+
+        const User = db.model('User', userSchema);
+        yield User.init();
+
+        const user1 = new User({ name: 'Hafez1_gh-9673-3' });
+        const user2 = new User({ name: 'Hafez1_gh-9673-3' });
+
+        assert.equal(user1.isNew, true);
+        assert.equal(user2.isNew, true);
+
+        yield User.bulkSave([user1, user2]);
+
+        assert.equal(user1.isNew, false);
+        assert.equal(user2.isNew, false);
+      });
+    });
+    it('sets `isNew` to false when a document succeds and `isNew` does not change when some fail', () => {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String, unique: true }
+        });
+
+        const User = db.model('User', userSchema);
+        yield User.init();
+
+        const user1 = new User({ name: 'Hafez1_gh-9673-4' });
+        const user2 = new User({ name: 'Hafez1_gh-9673-4' });
+
+        const err = yield User.bulkSave([user1, user2]).then(() => null, err => err);
+
+        assert.ok(err);
+        assert.equal(user1.isNew, false);
+        assert.equal(user2.isNew, true);
+      });
+    });
+    it('changes documents state for successful writes', () => {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: { type: String, unique: true },
+          age: Number
+        });
+
+        const User = db.model('User', userSchema);
+        yield User.init();
+
+        const user1 = new User({ name: 'Sam', age: 26 });
+        const user2 = new User({ name: 'Sam', age: 27 });
+
+        assert.equal(user1.isNew, true);
+        assert.equal(user2.isNew, true);
+
+        const err = yield User.bulkSave([user1, user2]).then(() => null, err => err);
+
+        assert.ok(err);
+        assert.deepEqual(user1.getChanges(), {});
+        assert.deepEqual(user2.getChanges(), { $set: { age: 27, name: 'Sam' } });
+      });
+    });
+    it('triggers pre/post-save hooks', () => {
+      return co(function* () {
+        const userSchema = new Schema({
+          name: String,
+          age: Number
+        });
+
+        let preSaveCallCount = 0;
+        let postSaveCallCount = 0;
+
+        userSchema.pre('save', function() {
+          preSaveCallCount++;
+        });
+        userSchema.post('save', function() {
+          postSaveCallCount++;
+        });
+
+        const User = db.model('User', userSchema);
+
+        const user1 = new User({ name: 'Sam1' });
+        const user2 = new User({ name: 'Sam2' });
+
+
+        yield User.bulkSave([user1, user2]);
+        assert.equal(preSaveCallCount, 2);
+        assert.equal(postSaveCallCount, 2);
+      });
+    });
+    it('calls pre-save before actually saving', () => {
+      return co(function* () {
+        const userSchema = new Schema({ name: String });
+
+
+        userSchema.pre('save', function() {
+          this.name = 'name from pre-save';
+        });
+
+        const User = db.model('User', userSchema);
+
+        const user1 = new User({ name: 'Sam1' });
+        const user2 = new User({ name: 'Sam2' });
+
+
+        yield User.bulkSave([user1, user2]);
+
+        const usersFromDatabase = yield User.find({ _id: { $in: [user1._id, user2._id] } }).sort('_id');
+        assert.equal(usersFromDatabase[0].name, 'name from pre-save');
+        assert.equal(usersFromDatabase[1].name, 'name from pre-save');
+      });
+    });
   });
-});
+});
\ No newline at end of file

From facb01149ff0b358bc92602eb997e288da3a0e34 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 10 Apr 2021 10:48:41 +0200
Subject: [PATCH 1869/2348] fix execPost('save') in bulkSave(...)

---
 lib/model.js | 35 ++++++++++++++++++++++-------------
 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index a7463b3c416..b4f332833cc 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3526,17 +3526,7 @@ Model.bulkWrite = function(ops, options, callback) {
 Model.bulkSave = function(documents) {
   const writeOperations = this.buildBulkWriteOperations(documents);
 
-  const preSavePromises = documents.map((document) => {
-    return new Promise((resolve, reject) => {
-      document.schema.s.hooks.execPre('save', document, (err) => {
-        if (err) {
-          reject(err);
-          return;
-        }
-        resolve();
-      });
-    });
-  });
+  const preSavePromises = documents.map(buildPreSavePromise);
 
   let bulkWriteResultPromise;
   return Promise.all(preSavePromises)
@@ -3564,18 +3554,37 @@ Model.bulkSave = function(documents) {
     });
 };
 
+function buildPreSavePromise(document) {
+  return new Promise((resolve, reject) => {
+    document.schema.s.hooks.execPre('save', document, (err) => {
+      if (err) {
+        reject(err);
+        return;
+      }
+      resolve();
+    });
+  });
+}
+
 function buildSuccessfulWriteHandlerPromise(document) {
   return new Promise((resolve, reject) => {
     handleSuccessfulWrite(document, resolve, reject);
   });
 }
 
-function handleSuccessfulWrite(document, resolve) {
+function handleSuccessfulWrite(document, resolve, reject) {
   if (document.isNew) {
     _setIsNew(document, false);
   }
-  resolve();
+
   document.$__reset();
+  document.schema.s.hooks.execPost('save', document, {}, (err) => {
+    if (err) {
+      reject(err);
+      return;
+    }
+    resolve();
+  });
 }
 
 

From 132b992ef7c411bb2a8a17740944ac3d363bce0f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 10 Apr 2021 10:58:34 +0200
Subject: [PATCH 1870/2348] run pre-save middleware before trying to build
 write operations

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 77559b9dde1..728db372e80 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3532,10 +3532,10 @@ Model.bulkWrite = function(ops, options, callback) {
  *
  */
 Model.bulkSave = function(documents) {
-  const writeOperations = this.buildBulkWriteOperations(documents);
-
   const preSavePromises = documents.map(buildPreSavePromise);
 
+  const writeOperations = this.buildBulkWriteOperations(documents);
+
   let bulkWriteResultPromise;
   return Promise.all(preSavePromises)
     .then(() => bulkWriteResultPromise = this.bulkWrite(writeOperations))

From e10b9d1e0fc9cad22651b34d3e3ed3d4a030337b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 10 Apr 2021 17:34:42 -0400
Subject: [PATCH 1871/2348] fix(index.d.ts): allow setting SchemaType `index`
 property to a string

Fix #10077
---
 index.d.ts                | 2 +-
 test/typescript/schema.ts | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 5bd3928a3df..5fef56c7f05 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1435,7 +1435,7 @@ declare module 'mongoose' {
      * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
      * build an index on this path when the model is compiled.
      */
-    index?: boolean | number | IndexOptions;
+    index?: boolean | number | IndexOptions | "2d" | "2dsphere" | "hashed" | "text";
 
     /**
      * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index a5561b49363..bdb6446c9f2 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -23,7 +23,10 @@ interface Movie {
 }
 
 const movieSchema = new Schema<Document<Movie>, Model<Document<Movie>>, Movie>({
-  title: String,
+  title: {
+    type: String,
+    index: 'text'
+  },
   featuredIn: {
     type: String,
     enum: ['Favorites', null],

From a8c312d6301c5c2a1cfc1cbaca86b87ba6ca30ad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 10 Apr 2021 19:10:32 -0400
Subject: [PATCH 1872/2348] test(populate): repro #10064

---
 test/model.populate.test.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a5cea0a105c..26562151430 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10077,6 +10077,38 @@ describe('model: populate:', function() {
     });
   });
 
+  it('transform to primitive (gh-10064)', function() {
+    const Child = db.model('Child', mongoose.Schema({ name: String }));
+    const Parent = db.model('Parent', mongoose.Schema({
+      child: { type: 'ObjectId', ref: 'Child' },
+      children: [{ type: 'ObjectId', ref: 'Child' }]
+    }));
+
+    return co(function*() {
+      const children = yield Child.create([{ name: 'Luke' }, { name: 'Leia' }]);
+
+      let doc = yield Parent.create({ children, child: children[0] });
+      doc = yield Parent.findById(doc).populate([
+        {
+          path: 'child',
+          transform: getName
+        },
+        {
+          path: 'children',
+          options: { retainNullValues: true },
+          transform: getName
+        }
+      ]);
+
+      function getName(doc) {
+        return doc == null ? null : doc.name;
+      }
+
+      assert.equal(doc.child, 'Luke');
+      assert.deepEqual(doc.toObject().children.sort().reverse(), ['Luke', 'Leia']);
+    });
+  });
+
   it('transform with virtual populate, justOne = true (gh-3375)', function() {
     const parentSchema = new Schema({
       name: String

From be1e62f1fe95fb742f591b690f1b57982b51f204 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 10 Apr 2021 19:10:43 -0400
Subject: [PATCH 1873/2348] fix(populate): allow returning primitive from
 `transform()` function for single conventional populate

Fix #10064
---
 index.d.ts               |  2 +-
 lib/document.js          | 18 +++++++---------
 lib/schema/buffer.js     | 42 ++++++++++++++++---------------------
 lib/schema/decimal128.js | 35 +------------------------------
 lib/schema/number.js     | 27 +-----------------------
 lib/schema/objectid.js   | 38 ++-------------------------------
 lib/schema/string.js     | 29 ++------------------------
 lib/schematype.js        | 45 ++++++++++++++++++++++++++++++++++++++++
 8 files changed, 77 insertions(+), 159 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 5fef56c7f05..3d2b212846a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1435,7 +1435,7 @@ declare module 'mongoose' {
      * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose will
      * build an index on this path when the model is compiled.
      */
-    index?: boolean | number | IndexOptions | "2d" | "2dsphere" | "hashed" | "text";
+    index?: boolean | number | IndexOptions | '2d' | '2dsphere' | 'hashed' | 'text';
 
     /**
      * If [truthy](https://masteringjs.io/tutorials/fundamentals/truthy), Mongoose
diff --git a/lib/document.js b/lib/document.js
index 127014cec1c..34f1838e1a6 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -4010,25 +4010,21 @@ Document.prototype.execPopulate = function(callback) {
 
 Document.prototype.populated = function(path, val, options) {
   // val and options are internal
-  if (val === null || val === void 0) {
+  if (val == null || val === true) {
     if (!this.$__.populated) {
       return undefined;
     }
-    const v = this.$__.populated[path];
+
+    // Map paths can be populated with either `path.$*` or just `path`
+    const _path = path.endsWith('.$*') ? path.replace(/\.\$\*$/, '') : path;
+
+    const v = this.$__.populated[_path];
     if (v) {
-      return v.value;
+      return val === true ? v : v.value;
     }
     return undefined;
   }
 
-  // internal
-  if (val === true) {
-    if (!this.$__.populated) {
-      return undefined;
-    }
-    return this.$__.populated[path];
-  }
-
   this.$__.populated || (this.$__.populated = {});
   this.$__.populated[path] = { value: val, options: options };
 
diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index c5b8cb7a114..14a7a0b4a7c 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -124,36 +124,30 @@ SchemaBuffer.prototype.checkRequired = function(value, doc) {
 SchemaBuffer.prototype.cast = function(value, doc, init) {
   let ret;
   if (SchemaType._isRef(this, value, doc, init)) {
-    // wait! we may need to cast this to a document
-
-    if (value === null || value === undefined) {
-      return value;
-    }
-
-    // lazy load
-    Document || (Document = require('./../document'));
-
-    if (value instanceof Document) {
-      value.$__.wasPopulated = true;
+    if (value && value.isMongooseBuffer) {
       return value;
     }
-
-    // setting a populated path
+  
     if (Buffer.isBuffer(value)) {
+      if (!value || !value.isMongooseBuffer) {
+        value = new MongooseBuffer(value, [this.path, doc]);
+        if (this.options.subtype != null) {
+          value._subtype = this.options.subtype;
+        }
+      }
       return value;
-    } else if (!utils.isObject(value)) {
-      throw new CastError('Buffer', value, this.path, null, this);
+    }
+  
+    if (value instanceof Binary) {
+      ret = new MongooseBuffer(value.value(true), [this.path, doc]);
+      if (typeof value.sub_type !== 'number') {
+        throw new CastError('Buffer', value, this.path, null, this);
+      }
+      ret._subtype = value.sub_type;
+      return ret;
     }
 
-    // Handle the case where user directly sets a populated
-    // path to a plain object; cast to the Model used in
-    // the population query.
-    const path = doc.$__fullPath(this.path);
-    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
-    const pop = owner.populated(path, true);
-    ret = new pop.options[populateModelSymbol](value);
-    ret.$__.wasPopulated = true;
-    return ret;
+    return this._castRef(value, doc, init);
   }
 
   // documents
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index 0c8038f207d..f96fa57f23e 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -168,44 +168,11 @@ Decimal128.prototype.checkRequired = function checkRequired(value, doc) {
 
 Decimal128.prototype.cast = function(value, doc, init) {
   if (SchemaType._isRef(this, value, doc, init)) {
-    // wait! we may need to cast this to a document
-
-    if (value === null || value === undefined) {
-      return value;
-    }
-
-    // lazy load
-    Document || (Document = require('./../document'));
-
-    if (value instanceof Document) {
-      value.$__.wasPopulated = true;
-      return value;
-    }
-
-    // setting a populated path
     if (value instanceof Decimal128Type) {
       return value;
-    } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('Decimal128', value, this.path, null, this);
-    }
-
-    // Handle the case where user directly sets a populated
-    // path to a plain object; cast to the Model used in
-    // the population query.
-    const path = doc.$__fullPath(this.path);
-    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
-    const pop = owner.populated(path, true);
-    let ret = value;
-    if (!doc.$__.populated ||
-        !doc.$__.populated[path] ||
-        !doc.$__.populated[path].options ||
-        !doc.$__.populated[path].options.options ||
-        !doc.$__.populated[path].options.options.lean) {
-      ret = new pop.options[populateModelSymbol](value);
-      ret.$__.wasPopulated = true;
     }
 
-    return ret;
+    return this._castRef(value, doc, init);
   }
 
   let castDecimal128;
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 85e96058084..44e7fb21ecd 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -350,36 +350,11 @@ SchemaNumber.prototype.enum = function(values, message) {
 
 SchemaNumber.prototype.cast = function(value, doc, init) {
   if (SchemaType._isRef(this, value, doc, init)) {
-    // wait! we may need to cast this to a document
-
-    if (value === null || value === undefined) {
-      return value;
-    }
-
-    // lazy load
-    Document || (Document = require('./../document'));
-
-    if (value instanceof Document) {
-      value.$__.wasPopulated = true;
-      return value;
-    }
-
-    // setting a populated path
     if (typeof value === 'number') {
       return value;
-    } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('Number', value, this.path, null, this);
     }
 
-    // Handle the case where user directly sets a populated
-    // path to a plain object; cast to the Model used in
-    // the population query.
-    const path = doc.$__fullPath(this.path);
-    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
-    const pop = owner.populated(path, true);
-    const ret = new pop.options[populateModelSymbol](value);
-    ret.$__.wasPopulated = true;
-    return ret;
+    return this._castRef(value, doc, init);
   }
 
   const val = value && typeof value._id !== 'undefined' ?
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index fb07c149bbd..157ed7d9257 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -10,8 +10,6 @@ const castObjectId = require('../cast/objectid');
 const oid = require('../types/objectid');
 const utils = require('../utils');
 
-const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-
 const CastError = SchemaType.CastError;
 let Document;
 
@@ -225,45 +223,13 @@ ObjectId.prototype.checkRequired = function checkRequired(value, doc) {
 ObjectId.prototype.cast = function(value, doc, init) {
   if (SchemaType._isRef(this, value, doc, init)) {
     // wait! we may need to cast this to a document
-
-    if (value === null || value === undefined) {
-      return value;
-    }
-
-    // lazy load
-    Document || (Document = require('./../document'));
-
-    if (value instanceof Document) {
-      value.$__.wasPopulated = true;
-      return value;
-    }
-
-    // setting a populated path
     if (value instanceof oid) {
       return value;
-    } else if ((value.constructor.name || '').toLowerCase() === 'objectid') {
+    } else if (value != null && (value.constructor.name || '').toLowerCase() === 'objectid') {
       return new oid(value.toHexString());
-    } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('ObjectId', value, this.path, null, this);
-    }
-
-    // Handle the case where user directly sets a populated
-    // path to a plain object; cast to the Model used in
-    // the population query.
-    const path = doc.$__fullPath(this.path);
-    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
-    const pop = owner.populated(path, true);
-    let ret = value;
-    if (!doc.$__.populated ||
-        !doc.$__.populated[path] ||
-        !doc.$__.populated[path].options ||
-        !doc.$__.populated[path].options.options ||
-        !doc.$__.populated[path].options.options.lean) {
-      ret = new pop.options[populateModelSymbol](value);
-      ret.$__.wasPopulated = true;
     }
 
-    return ret;
+    return this._castRef(value, doc, init);
   }
 
   let castObjectId;
diff --git a/lib/schema/string.js b/lib/schema/string.js
index ac9552b9ebc..b19d87fa47b 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -584,36 +584,11 @@ SchemaString.prototype.checkRequired = function checkRequired(value, doc) {
 
 SchemaString.prototype.cast = function(value, doc, init) {
   if (SchemaType._isRef(this, value, doc, init)) {
-    // wait! we may need to cast this to a document
-
-    if (value === null || value === undefined) {
-      return value;
-    }
-
-    // lazy load
-    Document || (Document = require('./../document'));
-
-    if (value instanceof Document) {
-      value.$__.wasPopulated = true;
-      return value;
-    }
-
-    // setting a populated path
     if (typeof value === 'string') {
       return value;
-    } else if (Buffer.isBuffer(value) || !utils.isObject(value)) {
-      throw new CastError('string', value, this.path, null, this);
     }
-
-    // Handle the case where user directly sets a populated
-    // path to a plain object; cast to the Model used in
-    // the population query.
-    const path = doc.$__fullPath(this.path);
-    const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
-    const pop = owner.populated(path, true);
-    const ret = new pop.options[populateModelSymbol](value);
-    ret.$__.wasPopulated = true;
-    return ret;
+    
+    return this._castRef(value, doc, init);
   }
 
   let castString;
diff --git a/lib/schematype.js b/lib/schematype.js
index 318a8399271..c1479e16589 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -17,6 +17,8 @@ const utils = require('./utils');
 const validatorErrorSymbol = require('./helpers/symbols').validatorErrorSymbol;
 const documentIsModified = require('./helpers/symbols').documentIsModified;
 
+const populateModelSymbol = require('./helpers/symbols').populateModelSymbol;
+
 const CastError = MongooseError.CastError;
 const ValidatorError = MongooseError.ValidatorError;
 
@@ -1427,11 +1429,54 @@ SchemaType._isRef = function(self, value, doc, init) {
     ) {
       return true;
     }
+
+    return init;
   }
 
   return false;
 };
 
+/*!
+ * ignore
+ */
+
+SchemaType.prototype._castRef = function _castRef(value, doc, init) {
+  if (value == null) {
+    return value;
+  }
+
+  if (value.$__ != null) {
+    value.$__.wasPopulated = true;
+    return value;
+  }
+
+  // setting a populated path
+  if (Buffer.isBuffer(value) || !utils.isObject(value)) {
+    if (init) {
+      return value;
+    }
+    throw new CastError(this.instance, value, this.path, null, this);
+  }
+
+  // Handle the case where user directly sets a populated
+  // path to a plain object; cast to the Model used in
+  // the population query.
+  const path = doc.$__fullPath(this.path);
+  const owner = doc.ownerDocument ? doc.ownerDocument() : doc;
+  const pop = owner.populated(path, true);
+  let ret = value;
+  if (!doc.$__.populated ||
+      !doc.$__.populated[path] ||
+      !doc.$__.populated[path].options ||
+      !doc.$__.populated[path].options.options ||
+      !doc.$__.populated[path].options.options.lean) {
+    ret = new pop.options[populateModelSymbol](value);
+    ret.$__.wasPopulated = true;
+  }
+
+  return ret;
+};
+
 /*!
  * ignore
  */

From 313eada9b7c4de6db9f27bc3831c880b5b685192 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 11 Apr 2021 17:29:04 -0400
Subject: [PATCH 1874/2348] style: fix lint

---
 lib/schema/buffer.js     | 7 ++-----
 lib/schema/decimal128.js | 4 ----
 lib/schema/number.js     | 3 ---
 lib/schema/string.js     | 5 +----
 4 files changed, 3 insertions(+), 16 deletions(-)

diff --git a/lib/schema/buffer.js b/lib/schema/buffer.js
index 14a7a0b4a7c..d8354166200 100644
--- a/lib/schema/buffer.js
+++ b/lib/schema/buffer.js
@@ -10,11 +10,8 @@ const SchemaType = require('../schematype');
 const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
-const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-
 const Binary = MongooseBuffer.Binary;
 const CastError = SchemaType.CastError;
-let Document;
 
 /**
  * Buffer SchemaType constructor
@@ -127,7 +124,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
     if (value && value.isMongooseBuffer) {
       return value;
     }
-  
+
     if (Buffer.isBuffer(value)) {
       if (!value || !value.isMongooseBuffer) {
         value = new MongooseBuffer(value, [this.path, doc]);
@@ -137,7 +134,7 @@ SchemaBuffer.prototype.cast = function(value, doc, init) {
       }
       return value;
     }
-  
+
     if (value instanceof Binary) {
       ret = new MongooseBuffer(value.value(true), [this.path, doc]);
       if (typeof value.sub_type !== 'number') {
diff --git a/lib/schema/decimal128.js b/lib/schema/decimal128.js
index f96fa57f23e..9c0e1d40d55 100644
--- a/lib/schema/decimal128.js
+++ b/lib/schema/decimal128.js
@@ -10,10 +10,6 @@ const Decimal128Type = require('../types/decimal128');
 const castDecimal128 = require('../cast/decimal128');
 const utils = require('../utils');
 
-const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-
-let Document;
-
 /**
  * Decimal128 SchemaType constructor.
  *
diff --git a/lib/schema/number.js b/lib/schema/number.js
index 44e7fb21ecd..2b2c1c1e4b3 100644
--- a/lib/schema/number.js
+++ b/lib/schema/number.js
@@ -11,10 +11,7 @@ const castNumber = require('../cast/number');
 const handleBitwiseOperator = require('./operators/bitwise');
 const utils = require('../utils');
 
-const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-
 const CastError = SchemaType.CastError;
-let Document;
 
 /**
  * Number SchemaType constructor.
diff --git a/lib/schema/string.js b/lib/schema/string.js
index b19d87fa47b..6778b5c48ed 100644
--- a/lib/schema/string.js
+++ b/lib/schema/string.js
@@ -10,10 +10,7 @@ const SchemaStringOptions = require('../options/SchemaStringOptions');
 const castString = require('../cast/string');
 const utils = require('../utils');
 
-const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
-
 const CastError = SchemaType.CastError;
-let Document;
 
 /**
  * String SchemaType constructor.
@@ -587,7 +584,7 @@ SchemaString.prototype.cast = function(value, doc, init) {
     if (typeof value === 'string') {
       return value;
     }
-    
+
     return this._castRef(value, doc, init);
   }
 

From 56bc6a4368cb0b5eb917cda27936d3e79237a673 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 11 Apr 2021 17:43:45 -0400
Subject: [PATCH 1875/2348] fix(connection): correctly handle running queued
 connection handlers when using `setClient()`

Re: #9778
---
 lib/connection.js              | 11 ++---------
 test/collection.capped.test.js |  2 +-
 2 files changed, 3 insertions(+), 10 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 8b6718da664..5d7b22b990d 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -992,15 +992,8 @@ function _setClient(conn, client, options, dbName) {
 
   delete conn.then;
   delete conn.catch;
-  conn.readyState = STATES.connected;
-
-  for (const i in conn.collections) {
-    if (utils.object.hasOwnProperty(conn.collections, i)) {
-      conn.collections[i].onOpen();
-    }
-  }
-
-  conn.emit('open');
+  
+  conn.onOpen();
 }
 
 /*!
diff --git a/test/collection.capped.test.js b/test/collection.capped.test.js
index a0270fa47a2..53def94437b 100644
--- a/test/collection.capped.test.js
+++ b/test/collection.capped.test.js
@@ -37,7 +37,7 @@ describe('collections: capped:', function() {
   });
 
   it('creation', function() {
-    this.timeout(30000);
+    this.timeout(15000);
 
     return co(function*() {
       yield db.dropCollection('Test').catch(() => {});

From 44891e3d3e006fba4225defde96a9e3dcd0f6f1d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 11 Apr 2021 17:49:07 -0400
Subject: [PATCH 1876/2348] style: fix lint

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 5d7b22b990d..2b90e53719c 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -992,7 +992,7 @@ function _setClient(conn, client, options, dbName) {
 
   delete conn.then;
   delete conn.catch;
-  
+
   conn.onOpen();
 }
 

From 5e09622d542682abd382d13a5d56faa49488d2c2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 11 Apr 2021 18:10:24 -0400
Subject: [PATCH 1877/2348] fix(index.d.ts): allow RHS of `$unset` properties
 to be any value

Fix #10066
---
 index.d.ts                 | 2 +-
 test/typescript/queries.ts | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 3d2b212846a..6ddbaf5ad3f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2280,7 +2280,7 @@ declare module 'mongoose' {
     $rename?: { [key: string]: string };
     $set?: mongodb.MatchKeysAndValues<TSchema>;
     $setOnInsert?: mongodb.MatchKeysAndValues<TSchema>;
-    $unset?: mongodb.OnlyFieldsOfType<TSchema, any, '' | 1 | true>;
+    $unset?: mongodb.OnlyFieldsOfType<TSchema, any, any>;
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-array/ */
     $addToSet?: mongodb.SetFields<TSchema>;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index f41cb35b1f2..98dfd500665 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -70,6 +70,9 @@ Test.findOneAndUpdate({ name: 'test' }, { $addToSet: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $pull: { docs: { 'nested.id': 1 } } });
 
+const update = Math.random() > 0.5 ? { $unset: { 'docs.0': 1 } } : { age: 55 };
+Test.findOneAndUpdate({ name: 'test' }, update);
+
 Test.findByIdAndUpdate({ name: 'test' }, { name: 'test2' }, (err, doc) => console.log(doc));
 
 const query: Query<ITest | null, ITest> = Test.findOne();

From 79bed7a2b31ca73c7d8755f9a252139069818990 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 11 Apr 2021 18:24:58 -0400
Subject: [PATCH 1878/2348] fix(index.d.ts): use correct `Date` type for
 `$currentDate`

Fix #10058
---
 index.d.ts                 | 3 ++-
 test/typescript/queries.ts | 6 +++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 6ddbaf5ad3f..435955c9636 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -13,6 +13,7 @@ declare module 'mongoose' {
   }
 
   /** The Mongoose Date [SchemaType](/docs/schematypes.html). */
+  class NativeDate extends global.Date {}
   export type Date = Schema.Types.Date;
 
   /**
@@ -2272,7 +2273,7 @@ declare module 'mongoose' {
   /** @see https://docs.mongodb.com/manual/reference/operator/update */
   type _UpdateQuery<TSchema> = {
     /** @see https://docs.mongodb.com/manual/reference/operator/update-field/ */
-    $currentDate?: mongodb.OnlyFieldsOfType<TSchema, Date | mongodb.Timestamp, true | { $type: 'date' | 'timestamp' }>;
+    $currentDate?: mongodb.OnlyFieldsOfType<TSchema, NativeDate | mongodb.Timestamp, true | { $type: 'date' | 'timestamp' }>;
     $inc?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined>;
     $min?: mongodb.MatchKeysAndValues<TSchema>;
     $max?: mongodb.MatchKeysAndValues<TSchema>;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 98dfd500665..53debe01b83 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -7,7 +7,8 @@ interface QueryHelpers {
 const schema: Schema<ITest, Model<ITest, QueryHelpers>> = new Schema({
   name: { type: 'String' },
   tags: [String],
-  docs: [{ nested: { id: Number } }]
+  docs: [{ nested: { id: Number } }],
+  endDate: Date
 });
 
 schema.query.byName = function(name: string): Query<any, ITest, QueryHelpers> & QueryHelpers {
@@ -24,6 +25,7 @@ interface ITest extends Document {
   parent?: Types.ObjectId;
   tags?: string[];
   docs?: ISubdoc[];
+  endDate?: Date;
 }
 
 const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
@@ -73,6 +75,8 @@ Test.findOneAndUpdate({ name: 'test' }, { $pull: { docs: { 'nested.id': 1 } } })
 const update = Math.random() > 0.5 ? { $unset: { 'docs.0': 1 } } : { age: 55 };
 Test.findOneAndUpdate({ name: 'test' }, update);
 
+Test.findOneAndUpdate({ name: 'test' }, { $currentDate: { endDate: true } });
+
 Test.findByIdAndUpdate({ name: 'test' }, { name: 'test2' }, (err, doc) => console.log(doc));
 
 const query: Query<ITest | null, ITest> = Test.findOne();

From fd489042667f28708e026b02c28b853ca305bb5b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 12 Apr 2021 10:21:06 -0400
Subject: [PATCH 1879/2348] testing test failures

---
 lib/helpers/populate/assignVals.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 3e11cbb1fe7..16a292d9dbf 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -242,11 +242,11 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (val instanceof Map) {
     return val;
   }
-
+  /*
   if (typeof populateOptions._queryProjection === 'undefined') {
     return transform(val, allIds);
   }
-
+  */
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }

From 97af299090a88f7ef4f1494eceda0c215c92a758 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 12 Apr 2021 10:46:58 -0400
Subject: [PATCH 1880/2348] Update assignVals.js

---
 lib/helpers/populate/assignVals.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 16a292d9dbf..3e11cbb1fe7 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -242,11 +242,11 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (val instanceof Map) {
     return val;
   }
-  /*
+
   if (typeof populateOptions._queryProjection === 'undefined') {
     return transform(val, allIds);
   }
-  */
+
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }

From 70361d0f4b61788106d17ebc4a50cdb777099c5f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Apr 2021 15:31:51 -0400
Subject: [PATCH 1881/2348] fix(populate): handle populating map paths using
 trailing `.$*`

Fix #10123
---
 lib/helpers/populate/assignVals.js | 17 +++++++++--------
 test/types.map.test.js             | 13 ++++++++++---
 2 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 2cbe3939cc6..0eef697fc85 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -74,8 +74,9 @@ module.exports = function assignVals(o) {
   }
 
   for (i = 0; i < docs.length; ++i) {
-    const existingVal = mpath.get(o.path, docs[i], lookupLocalFields);
-    if (existingVal == null && !getVirtual(o.originalModel.schema, o.path)) {
+    const _path = o.path.endsWith('.$*') ? o.path.slice(0, -3) : o.path;
+    const existingVal = mpath.get(_path, docs[i], lookupLocalFields);
+    if (existingVal == null && !getVirtual(o.originalModel.schema, _path)) {
       continue;
     }
 
@@ -99,7 +100,7 @@ module.exports = function assignVals(o) {
       utils.isPOJO(existingVal);
     // If we pass the first check, also make sure the local field's schematype
     // is map (re: gh-6460)
-    isMap = isMap && get(originalSchema._getSchema(o.path), '$isSchemaMap');
+    isMap = isMap && get(originalSchema._getSchema(_path), '$isSchemaMap');
     if (!o.isVirtual && isMap) {
       const _keys = existingVal instanceof Map ?
         Array.from(existingVal.keys()) :
@@ -121,14 +122,14 @@ module.exports = function assignVals(o) {
     }
 
     if (o.isVirtual && isDoc) {
-      docs[i].populated(o.path, o.justOne ? originalIds[0] : originalIds, o.allOptions);
+      docs[i].populated(_path, o.justOne ? originalIds[0] : originalIds, o.allOptions);
       // If virtual populate and doc is already init-ed, need to walk through
       // the actual doc to set rather than setting `_doc` directly
-      mpath.set(o.path, valueToSet, docs[i], setValue);
+      mpath.set(_path, valueToSet, docs[i], setValue);
       continue;
     }
 
-    const parts = o.path.split('.');
+    const parts = _path.split('.');
     let cur = docs[i];
     const curPath = parts[0];
     for (let j = 0; j < parts.length - 1; ++j) {
@@ -160,13 +161,13 @@ module.exports = function assignVals(o) {
       }
     }
     if (docs[i].$__) {
-      docs[i].populated(o.path, o.allIds[i], o.allOptions);
+      docs[i].populated(_path, o.allIds[i], o.allOptions);
     }
 
     // If lean, need to check that each individual virtual respects
     // `justOne`, because you may have a populated virtual with `justOne`
     // underneath an array. See gh-6867
-    mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
+    mpath.set(_path, valueToSet, docs[i], lookupLocalFields, setValue, false);
   }
 };
 
diff --git a/test/types.map.test.js b/test/types.map.test.js
index 839f250becc..13ff1c4c1f0 100644
--- a/test/types.map.test.js
+++ b/test/types.map.test.js
@@ -424,12 +424,12 @@ describe('Map', function() {
         const foo = yield Scene.create({ name: 'foo' });
         let event = yield Event.create({ scenes: { foo: foo._id } });
 
-        event = yield Event.findOne().populate('scenes');
+        event = yield Event.findOne().populate('scenes.$*');
         const bar = yield Scene.create({ name: 'bar' });
         event.scenes.set('bar', bar);
         yield event.save();
 
-        event = yield Event.findOne().populate('scenes');
+        event = yield Event.findOne().populate('scenes.$*');
         assert.ok(event.scenes.has('bar'));
         assert.equal(event.scenes.get('bar').name, 'bar');
       });
@@ -465,9 +465,16 @@ describe('Map', function() {
           }
         });
 
-        const doc = yield Test.findOne().populate('books.$*.author');
+        let doc = yield Test.findOne().populate('books.$*.author');
 
         assert.equal(doc.books.get('key1').author.name, 'Ian Fleming');
+
+        doc.books.set('key2', { title: 'Live and Let Die', author: person._id });
+        yield doc.save();
+
+        doc = yield Test.findOne().populate('books.$*.author');
+
+        assert.equal(doc.books.get('key2').author.name, 'Ian Fleming');
       });
     });
   });

From fcc97c06d9ef495dd81c67ea59bb6c11b8415e03 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Apr 2021 16:22:52 -0400
Subject: [PATCH 1882/2348] test(populate): repro #10069

---
 test/model.populate.test.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 26562151430..951dbc0560d 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10232,4 +10232,36 @@ describe('model: populate:', function() {
       assert.equal(modelA1._modelB._rootModel.name, 'my name');
     });
   });
+
+  it('populates lean subdoc with `_id` property (gh-10069)', function() {
+    const Books = db.model('Book', new Schema({ name: String, author: Schema.Types.ObjectId }));
+    const Authors = db.model('Person', new Schema({ name: String }));
+
+    return co(function*() {
+      const anAuthor = new Authors({ name: 'Author1' });
+      yield anAuthor.save();
+
+      const aBook1 = new Books({ name: 'Book1', author: anAuthor.id });
+      yield aBook1.save();
+      const aBook2 = new Books({ name: 'Book2', author: anAuthor.id });
+      yield aBook2.save();
+
+      const populateOptions = [{
+        path: 'author',
+        model: 'Person'
+      }];
+
+      const books = (yield Books.find().lean()).map(aBook => {
+        if (!aBook._id.equals(aBook1.id)) {
+          aBook.author = { _id: aBook.author };
+        }
+        return aBook;
+      });
+
+      const populatedBooks = yield Books.populate(books, populateOptions);
+      assert.equal(populatedBooks.length, 2);
+      assert.equal(populatedBooks[0].author.name, 'Author1');
+      assert.equal(populatedBooks[1].author.name, 'Author1');
+    });
+  });
 });

From 149556293f10b54645a473ba42da145159c436ba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Apr 2021 16:23:09 -0400
Subject: [PATCH 1883/2348] fix(populate): correctly populate lean subdocs with
 `_id` property

Fix #10069
---
 lib/helpers/populate/getModelsMapForPopulate.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 7d26093fe52..9e55c45d542 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -501,7 +501,12 @@ function handleRefFunction(ref, doc) {
  */
 
 function convertTo_id(val, schema) {
-  if (val != null && val.$__ != null) return val._id;
+  if (val != null && val.$__ != null) {
+    return val._id;
+  }
+  if (val != null && val._id != null && (schema == null || !schema.$isSchemaMap)) {
+    return val._id;
+  }
 
   if (Array.isArray(val)) {
     for (let i = 0; i < val.length; ++i) {

From 75eba1e00097a2a392ff7a02c4a77dee4e16daa3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Apr 2021 17:56:50 -0400
Subject: [PATCH 1884/2348] fix(index.d.ts): allow `$pull` with `$` paths

Fix #10075
---
 index.d.ts                 | 20 ++++++++++----------
 test/typescript/queries.ts |  5 ++++-
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 435955c9636..0b459f93cf2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2260,15 +2260,15 @@ declare module 'mongoose' {
   }[keyof TSchema];
 
   type PullOperator<TSchema> = {
-      [key in KeysOfAType<TSchema, ReadonlyArray<any>>]?:
-          | Partial<Unpacked<TSchema[key]>>
-          | mongodb.ObjectQuerySelector<Unpacked<TSchema[key]>>
-          // Doesn't look like TypeScript has good support for creating an
-          // object containing dotted keys:
-          // https://stackoverflow.com/questions/58434389/typescript-deep-keyof-of-a-nested-object
-          | mongodb.QuerySelector<any>
-          | any;
-  };
+    [key in KeysOfAType<TSchema, ReadonlyArray<any>>]?:
+        | Partial<Unpacked<TSchema[key]>>
+        | mongodb.ObjectQuerySelector<Unpacked<TSchema[key]>>
+        // Doesn't look like TypeScript has good support for creating an
+        // object containing dotted keys:
+        // https://stackoverflow.com/questions/58434389/typescript-deep-keyof-of-a-nested-object
+        | mongodb.QuerySelector<any>
+        | any;
+  } | any; // Because TS doesn't have good support for creating an object with dotted keys, including `.$.` re: #10075
 
   /** @see https://docs.mongodb.com/manual/reference/operator/update */
   type _UpdateQuery<TSchema> = {
@@ -2292,7 +2292,7 @@ declare module 'mongoose' {
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-bitwise/ */
     $bit?: {
-        [key: string]: { [key in 'and' | 'or' | 'xor']?: number };
+      [key: string]: { [key in 'and' | 'or' | 'xor']?: number };
     };
   };
 
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 53debe01b83..df22aa8b41d 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -7,7 +7,7 @@ interface QueryHelpers {
 const schema: Schema<ITest, Model<ITest, QueryHelpers>> = new Schema({
   name: { type: 'String' },
   tags: [String],
-  docs: [{ nested: { id: Number } }],
+  docs: [{ nested: { id: Number, tags: [String] } }],
   endDate: Date
 });
 
@@ -17,6 +17,7 @@ schema.query.byName = function(name: string): Query<any, ITest, QueryHelpers> &
 
 interface ISubdoc extends Document {
   id?: number;
+  tags?: string[];
 }
 
 interface ITest extends Document {
@@ -72,6 +73,8 @@ Test.findOneAndUpdate({ name: 'test' }, { $addToSet: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $push: { tags: 'each' } });
 Test.findOneAndUpdate({ name: 'test' }, { $pull: { docs: { 'nested.id': 1 } } });
 
+Test.findOneAndUpdate({ name: 'test', 'docs.id': 1 }, { $pull: { 'docs.$.tags': 'foo' } });
+
 const update = Math.random() > 0.5 ? { $unset: { 'docs.0': 1 } } : { age: 55 };
 Test.findOneAndUpdate({ name: 'test' }, update);
 

From 8a62f8721346bf8885bc4970e5bb75a384d909f6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Apr 2021 18:02:55 -0400
Subject: [PATCH 1885/2348] fix: upgrade mongodb driver -> 3.6.6

Fix #10079
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index a0808b8ebc1..e4a8302ad3d 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.5",
+    "mongodb": "3.6.6",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.5",

From 2f0c195af2d042343b03893fdbc9eada9afc26d0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Apr 2021 20:43:06 -0400
Subject: [PATCH 1886/2348] fix(index.d.ts): allow generic classes of `T` to
 use `T & Document` internally

Fix #10046
---
 index.d.ts                   |  2 +-
 test/typescript/generics.ts  | 15 +++++++++++++++
 test/typescript/main.test.js |  8 ++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 test/typescript/generics.ts

diff --git a/index.d.ts b/index.d.ts
index 0b459f93cf2..617b1b13624 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -374,7 +374,7 @@ declare module 'mongoose' {
     _id?: T;
 
     /** This documents __v. */
-    __v?: number;
+    __v?: any;
 
     /* Get all subdocs (by bfs) */
     $getAllSubdocs(): Document[];
diff --git a/test/typescript/generics.ts b/test/typescript/generics.ts
new file mode 100644
index 00000000000..595590ea7fa
--- /dev/null
+++ b/test/typescript/generics.ts
@@ -0,0 +1,15 @@
+import { Model, Document } from 'mongoose';
+
+class Repository<T> {
+  private readonly Model: Model<T & Document>
+
+  findById(id:string): Promise<T & Document> {
+    return Model.findById(id).exec();
+  }
+}
+
+class Foo {
+  name: string
+}
+
+type Test = Repository<Foo>;
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index e6fc87c062a..513950f97df 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -198,6 +198,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('generics', function() {
+    const errors = runTest('generics.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file, configOverride) {

From 4893c4f7c1a125db7e9a0d41c640159df22203b4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 13 Apr 2021 20:16:12 -0400
Subject: [PATCH 1887/2348] fix(populate): support populating embedded
 discriminators in nested arrays

Re: #9984
---
 lib/helpers/populate/getSchemaTypes.js       | 21 ++++++++++--
 test/helpers/populate.getSchemaTypes.test.js | 18 ++++++++++
 test/model.discriminator.test.js             | 36 ++++++++++++++++++++
 3 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index 1e89f4b174f..fdad82641f0 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -121,17 +121,34 @@ module.exports = function getSchemaTypes(schema, doc, path) {
             foundschema.$isMongooseArray &&
             foundschema.casterConstructor.$isMongooseArray) {
           // Nested arrays. Drill down to the bottom of the nested array.
-          // Ignore discriminators.
           let type = foundschema;
           while (type.$isMongooseArray && !type.$isMongooseDocumentArray) {
             type = type.casterConstructor;
           }
-          return search(
+
+          const ret = search(
             parts.slice(p),
             type.schema,
             null,
             nestedPath.concat(parts.slice(0, p))
           );
+          if (ret != null) {
+            return ret;
+          }
+
+          if (type.schema.discriminators) {
+            const discriminatorPaths = [];
+            for (const discriminatorName of Object.keys(type.schema.discriminators)) {
+              const _schema = type.schema.discriminators[discriminatorName];
+              const ret = search(parts.slice(p), _schema, null, nestedPath.concat(parts.slice(0, p)));
+              if (ret != null) {
+                discriminatorPaths.push(ret);
+              }
+            }
+            if (discriminatorPaths.length > 0) {
+              return discriminatorPaths;
+            }
+          }
         }
       }
 
diff --git a/test/helpers/populate.getSchemaTypes.test.js b/test/helpers/populate.getSchemaTypes.test.js
index b13dd9da84f..20ba5dc8718 100644
--- a/test/helpers/populate.getSchemaTypes.test.js
+++ b/test/helpers/populate.getSchemaTypes.test.js
@@ -166,4 +166,22 @@ describe('getSchemaTypes', function() {
 
     done();
   });
+
+  it('handles embedded discriminators in nested arrays (gh-9984)', function() {
+    const mapSchema = new Schema({
+      tiles: [[new Schema({}, { discriminatorKey: 'kind', _id: false })]]
+    });
+
+    const contentPath = mapSchema.path('tiles');
+
+    contentPath.discriminator('Enemy', new Schema({
+      enemy: { type: Schema.Types.ObjectId, ref: 'Enemy' }
+    }));
+    contentPath.discriminator('Wall', new Schema({ color: String }));
+
+    const schemaTypes = getSchemaTypes(mapSchema, null, 'tiles.enemy');
+    assert.ok(Array.isArray(schemaTypes));
+    assert.equal(schemaTypes.length, 1);
+    assert.equal(schemaTypes[0].options.ref, 'Enemy');
+  });
 });
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 02b46d5ac7f..08ee207c06c 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1646,6 +1646,42 @@ describe('model', function() {
     assert.ok(actions.schema.discriminators['message']);
   });
 
+  it('embedded discriminator array of arrays (gh-9984)', function() {
+    const enemySchema = new Schema({
+      name: String,
+      level: Number
+    });
+    const Enemy = db.model('Enemy', enemySchema);
+
+    const mapSchema = new Schema({
+      tiles: [[new Schema({}, { discriminatorKey: 'kind', _id: false })]]
+    });
+
+    const contentPath = mapSchema.path('tiles');
+
+    contentPath.discriminator('Enemy', new Schema({
+      enemy: { type: Schema.Types.ObjectId, ref: 'Enemy' }
+    }));
+    contentPath.discriminator('Wall', new Schema({ color: String }));
+
+    const Map = db.model('Map', mapSchema);
+
+    return co(function*() {
+      const e = yield Enemy.create({
+        name: 'Bowser',
+        level: 10
+      });
+
+      let map = yield Map.create({
+        tiles: [[{ kind: 'Enemy', enemy: e._id }, { kind: 'Wall', color: 'Blue' }]]
+      });
+
+      map = yield Map.findById(map).populate({ path: 'tiles.enemy' });
+      console.log(map.tiles);
+      assert.equal(map.tiles[0][0].enemy.name, 'Bowser');
+    });
+  });
+
   it('recursive embedded discriminator using schematype (gh-9600)', function() {
     const contentSchema = new mongoose.Schema({}, { discriminatorKey: 'type' });
     const nestedSchema = new mongoose.Schema({

From 0614913843d7b0d0fb9a53f6353b98b1fc6bb9bd Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:28:48 +0200
Subject: [PATCH 1888/2348] add "tdd" script in package.json

---
 package.json | 37 ++++++++++++++++++-------------------
 1 file changed, 18 insertions(+), 19 deletions(-)

diff --git a/package.json b/package.json
index e4a8302ad3d..c54a50004ca 100644
--- a/package.json
+++ b/package.json
@@ -79,6 +79,7 @@
     "release": "git pull && git push origin master --tags && npm publish",
     "release-legacy": "git pull origin 4.x && git push origin 4.x --tags && npm publish --tag legacy",
     "test": "mocha --exit ./test/*.test.js ./test/typescript/main.test.js",
+    "tdd": "mocha ./test/*.test.js ./test/typescript/main.test.js --watch --recursive --watch-files ./**/*.js",
     "test-cov": "nyc --reporter=html --reporter=text npm test"
   },
   "main": "./index.js",
@@ -106,25 +107,23 @@
     "extends": [
       "eslint:recommended"
     ],
-    "overrides": [
-      {
-        "files": [
-          "**/*.{ts,tsx}"
-        ],
-        "extends": [
-          "plugin:@typescript-eslint/eslint-recommended",
-          "plugin:@typescript-eslint/recommended"
-        ],
-        "plugins": [
-          "@typescript-eslint"
-        ],
-        "rules": {
-          "@typescript-eslint/no-explicit-any": "off",
-          "@typescript-eslint/ban-types": "off",
-          "@typescript-eslint/no-unused-vars": "off"
-        }
+    "overrides": [{
+      "files": [
+        "**/*.{ts,tsx}"
+      ],
+      "extends": [
+        "plugin:@typescript-eslint/eslint-recommended",
+        "plugin:@typescript-eslint/recommended"
+      ],
+      "plugins": [
+        "@typescript-eslint"
+      ],
+      "rules": {
+        "@typescript-eslint/no-explicit-any": "off",
+        "@typescript-eslint/ban-types": "off",
+        "@typescript-eslint/no-unused-vars": "off"
       }
-    ],
+    }],
     "plugins": [
       "mocha-no-only"
     ],
@@ -248,4 +247,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
+}
\ No newline at end of file

From 68f01de44559153f7a6413671e9908674dc32d10 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:36:56 +0200
Subject: [PATCH 1889/2348] feature(utils): add errorToPOJO utility

---
 lib/utils.js       | 13 +++++++++++++
 test/utils.test.js | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/lib/utils.js b/lib/utils.js
index ce69c9f87a5..59ef7e04985 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -920,3 +920,16 @@ exports.getOption = function(name) {
  */
 
 exports.noop = function() {};
+
+exports.errorToPOJO = function errorToPOJO(error) {
+  const isError = error instanceof Error;
+  if (!isError) {
+    throw new Error('`error` must be `instanceof Error`.');
+  }
+
+  const ret = {};
+  for (const properyName of Object.getOwnPropertyNames(error)) {
+    ret[properyName] = error[properyName];
+  }
+  return ret;
+};
\ No newline at end of file
diff --git a/test/utils.test.js b/test/utils.test.js
index 2c9a83ebf53..21f3907371a 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -365,4 +365,47 @@ describe('utils', function() {
       assert.deepEqual(out, o);
     });
   });
+  describe('errorToPOJO(...)', () => {
+    it('converts an error to a POJO', () => {
+      // Arrange
+      const err = new Error('Something bad happened.');
+      err.metadata = { hello: 'world' };
+
+      // Act
+      const pojoError = utils.errorToPOJO(err);
+
+      // Assert
+      assert.equal(pojoError.message, 'Something bad happened.');
+      assert.ok(pojoError.stack);
+      assert.deepEqual(pojoError.metadata, { hello: 'world' });
+    });
+    it('throws an error when argument is not an error object', () => {
+      let errorWhenConverting;
+      try {
+        utils.errorToPOJO({ message: 'I am a POJO', stack: 'Does not matter' });
+      } catch (_err) {
+        errorWhenConverting = _err;
+      }
+      assert.equal(errorWhenConverting.message, '`error` must be `instanceof Error`.');
+    });
+    it('works with classes that extend `Error`', () => {
+      // Arrange
+      class OperationalError extends Error {
+        constructor() {
+          super(...arguments);
+        }
+      }
+
+      const err = new OperationalError('Something bad happened.');
+      err.metadata = { hello: 'world' };
+
+      // Act
+      const pojoError = utils.errorToPOJO(err);
+
+      // Assert
+      assert.equal(pojoError.message, 'Something bad happened.');
+      assert.ok(pojoError.stack);
+      assert.deepEqual(pojoError.metadata, { hello: 'world' });
+    });
+  });
 });

From ecb19b76d90c627e44bd912e4dfb0fefa772a8ae Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:37:27 +0200
Subject: [PATCH 1890/2348] test: repro #10126

---
 test/model.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 596f66d91e6..e48760c32f0 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7134,4 +7134,28 @@ describe('Model', function() {
       });
     });
   });
+
+  it('saves all error object properties to paths with type `Mixed` (gh-10126)', () => {
+    return co(function*() {
+      const userSchema = new Schema({ err: Schema.Types.Mixed });
+
+      const User = db.model('User', userSchema);
+
+      const err = new Error('I am a bad error');
+      err.metadata = { reasons: ['Cloudflare is down', 'DNS'] };
+
+      const user = yield User.create({ err });
+      const userFromDB = yield User.findOne({ _id: user._id });
+
+      assertErrorProperties(user);
+      assertErrorProperties(userFromDB);
+
+
+      function assertErrorProperties(user) {
+        assert.equal(user.err.message, 'I am a bad error');
+        assert.ok(user.err.stack);
+        assert.deepEqual(user.err.metadata, { reasons: ['Cloudflare is down', 'DNS'] });
+      }
+    });
+  });
 });

From b257c514e8b030afd8f1e08e6e3d41786ae9018b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:38:17 +0200
Subject: [PATCH 1891/2348] enhancement(schemaType): make `Mixed` cast errors
 to POJOs re #10126

---
 lib/schema/mixed.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 88e4db601f4..09944bf6039 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -7,6 +7,7 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const isObject = require('../helpers/isObject');
+const utils = require('../utils');
 
 /**
  * Mixed SchemaType constructor.
@@ -103,6 +104,9 @@ Mixed.set = SchemaType.set;
  */
 
 Mixed.prototype.cast = function(val) {
+  if (val instanceof Error) {
+    return utils.errorToPOJO(val);
+  }
   return val;
 };
 

From 79142e48d0fcd2e9e926535d76df692b1e81d024 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:41:58 +0200
Subject: [PATCH 1892/2348] add "tdd" script in package.json

---
 package.json | 37 ++++++++++++++++++-------------------
 1 file changed, 18 insertions(+), 19 deletions(-)

diff --git a/package.json b/package.json
index e4a8302ad3d..c54a50004ca 100644
--- a/package.json
+++ b/package.json
@@ -79,6 +79,7 @@
     "release": "git pull && git push origin master --tags && npm publish",
     "release-legacy": "git pull origin 4.x && git push origin 4.x --tags && npm publish --tag legacy",
     "test": "mocha --exit ./test/*.test.js ./test/typescript/main.test.js",
+    "tdd": "mocha ./test/*.test.js ./test/typescript/main.test.js --watch --recursive --watch-files ./**/*.js",
     "test-cov": "nyc --reporter=html --reporter=text npm test"
   },
   "main": "./index.js",
@@ -106,25 +107,23 @@
     "extends": [
       "eslint:recommended"
     ],
-    "overrides": [
-      {
-        "files": [
-          "**/*.{ts,tsx}"
-        ],
-        "extends": [
-          "plugin:@typescript-eslint/eslint-recommended",
-          "plugin:@typescript-eslint/recommended"
-        ],
-        "plugins": [
-          "@typescript-eslint"
-        ],
-        "rules": {
-          "@typescript-eslint/no-explicit-any": "off",
-          "@typescript-eslint/ban-types": "off",
-          "@typescript-eslint/no-unused-vars": "off"
-        }
+    "overrides": [{
+      "files": [
+        "**/*.{ts,tsx}"
+      ],
+      "extends": [
+        "plugin:@typescript-eslint/eslint-recommended",
+        "plugin:@typescript-eslint/recommended"
+      ],
+      "plugins": [
+        "@typescript-eslint"
+      ],
+      "rules": {
+        "@typescript-eslint/no-explicit-any": "off",
+        "@typescript-eslint/ban-types": "off",
+        "@typescript-eslint/no-unused-vars": "off"
       }
-    ],
+    }],
     "plugins": [
       "mocha-no-only"
     ],
@@ -248,4 +247,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
+}
\ No newline at end of file

From 2bfbdfde10f433a276dcf5d09630d274606b82c3 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:42:06 +0200
Subject: [PATCH 1893/2348] feature(utils): add errorToPOJO utility

---
 lib/utils.js       | 13 +++++++++++++
 test/utils.test.js | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/lib/utils.js b/lib/utils.js
index ce69c9f87a5..59ef7e04985 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -920,3 +920,16 @@ exports.getOption = function(name) {
  */
 
 exports.noop = function() {};
+
+exports.errorToPOJO = function errorToPOJO(error) {
+  const isError = error instanceof Error;
+  if (!isError) {
+    throw new Error('`error` must be `instanceof Error`.');
+  }
+
+  const ret = {};
+  for (const properyName of Object.getOwnPropertyNames(error)) {
+    ret[properyName] = error[properyName];
+  }
+  return ret;
+};
\ No newline at end of file
diff --git a/test/utils.test.js b/test/utils.test.js
index 2c9a83ebf53..21f3907371a 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -365,4 +365,47 @@ describe('utils', function() {
       assert.deepEqual(out, o);
     });
   });
+  describe('errorToPOJO(...)', () => {
+    it('converts an error to a POJO', () => {
+      // Arrange
+      const err = new Error('Something bad happened.');
+      err.metadata = { hello: 'world' };
+
+      // Act
+      const pojoError = utils.errorToPOJO(err);
+
+      // Assert
+      assert.equal(pojoError.message, 'Something bad happened.');
+      assert.ok(pojoError.stack);
+      assert.deepEqual(pojoError.metadata, { hello: 'world' });
+    });
+    it('throws an error when argument is not an error object', () => {
+      let errorWhenConverting;
+      try {
+        utils.errorToPOJO({ message: 'I am a POJO', stack: 'Does not matter' });
+      } catch (_err) {
+        errorWhenConverting = _err;
+      }
+      assert.equal(errorWhenConverting.message, '`error` must be `instanceof Error`.');
+    });
+    it('works with classes that extend `Error`', () => {
+      // Arrange
+      class OperationalError extends Error {
+        constructor() {
+          super(...arguments);
+        }
+      }
+
+      const err = new OperationalError('Something bad happened.');
+      err.metadata = { hello: 'world' };
+
+      // Act
+      const pojoError = utils.errorToPOJO(err);
+
+      // Assert
+      assert.equal(pojoError.message, 'Something bad happened.');
+      assert.ok(pojoError.stack);
+      assert.deepEqual(pojoError.metadata, { hello: 'world' });
+    });
+  });
 });

From dd968ac987dbbaaceed89e45d868602dd39f6b68 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:42:16 +0200
Subject: [PATCH 1894/2348] test: repro #10126

---
 test/model.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 70cb026e598..06fe7c49031 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7159,4 +7159,28 @@ describe('Model', function() {
       });
     });
   });
+
+  it('saves all error object properties to paths with type `Mixed` (gh-10126)', () => {
+    return co(function*() {
+      const userSchema = new Schema({ err: Schema.Types.Mixed });
+
+      const User = db.model('User', userSchema);
+
+      const err = new Error('I am a bad error');
+      err.metadata = { reasons: ['Cloudflare is down', 'DNS'] };
+
+      const user = yield User.create({ err });
+      const userFromDB = yield User.findOne({ _id: user._id });
+
+      assertErrorProperties(user);
+      assertErrorProperties(userFromDB);
+
+
+      function assertErrorProperties(user) {
+        assert.equal(user.err.message, 'I am a bad error');
+        assert.ok(user.err.stack);
+        assert.deepEqual(user.err.metadata, { reasons: ['Cloudflare is down', 'DNS'] });
+      }
+    });
+  });
 });

From 2f74747705c915cba9e3d9f33967d0dc877bb1ec Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:42:31 +0200
Subject: [PATCH 1895/2348] enhancement(schemaType): make `Mixed` cast errors
 to POJOs re #10126

---
 lib/schema/mixed.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/schema/mixed.js b/lib/schema/mixed.js
index 88e4db601f4..09944bf6039 100644
--- a/lib/schema/mixed.js
+++ b/lib/schema/mixed.js
@@ -7,6 +7,7 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const isObject = require('../helpers/isObject');
+const utils = require('../utils');
 
 /**
  * Mixed SchemaType constructor.
@@ -103,6 +104,9 @@ Mixed.set = SchemaType.set;
  */
 
 Mixed.prototype.cast = function(val) {
+  if (val instanceof Error) {
+    return utils.errorToPOJO(val);
+  }
   return val;
 };
 

From 6c42fecc678e2d2c093cd44df277e3c58f4edb38 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 14 Apr 2021 07:59:59 +0200
Subject: [PATCH 1896/2348] fix spread for node 4

---
 test/utils.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/utils.test.js b/test/utils.test.js
index 21f3907371a..44cd7b202ab 100644
--- a/test/utils.test.js
+++ b/test/utils.test.js
@@ -391,8 +391,8 @@ describe('utils', function() {
     it('works with classes that extend `Error`', () => {
       // Arrange
       class OperationalError extends Error {
-        constructor() {
-          super(...arguments);
+        constructor(message) {
+          super(message);
         }
       }
 

From 7ec2c7ce7754c8b9d08cd4e097ec6d13abd4961a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 14 Apr 2021 12:47:41 -0400
Subject: [PATCH 1897/2348] might have fixed it

---
 lib/helpers/populate/assignVals.js | 14 ++++----------
 lib/model.js                       |  1 -
 2 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 3e11cbb1fe7..9b2540dee3d 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -165,7 +165,7 @@ module.exports = function assignVals(o) {
     // If lean, need to check that each individual virtual respects
     // `justOne`, because you may have a populated virtual with `justOne`
     // underneath an array. See gh-6867
-    return mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
+    mpath.set(o.path, valueToSet, docs[i], lookupLocalFields, setValue, false);
   }
 };
 
@@ -234,19 +234,13 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   }
 
   // findOne
-  if (isPopulatedObject(val)) {
+  if (isPopulatedObject(val) || utils.isPOJO(val)) {
     maybeRemoveId(val, assignmentOpts);
     return transform(val, allIds);
   }
-
   if (val instanceof Map) {
     return val;
   }
-
-  if (typeof populateOptions._queryProjection === 'undefined') {
-    return transform(val, allIds);
-  }
-
   if (populateOptions.justOne === true) {
     return val == null ? transform(val, allIds) : transform(null, allIds);
   }
@@ -254,6 +248,7 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
   if (populateOptions.justOne === false) {
     return [];
   }
+
   return val == null ? transform(val, allIds) : transform(null, allIds);
 }
 
@@ -280,8 +275,7 @@ function isPopulatedObject(obj) {
   if (obj == null) {
     return false;
   }
-  // if(typeof obj.$__ == 'undefined') return true;
-  // need to add new or statement
+
   return Array.isArray(obj) ||
     obj.$isMongooseMap ||
     obj.$__ != null ||
diff --git a/lib/model.js b/lib/model.js
index ac731411db4..704b584eb66 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4527,7 +4527,6 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
     for (const val of docs) {
       leanPopulateMap.set(val, mod.model);
     }
-
     callback(null, docs);
   });
 }

From 2736bcf9a69f83e4e62a357e29c7979d3095ddcb Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 14 Apr 2021 17:42:50 -0400
Subject: [PATCH 1898/2348] removed a redundant if statement

---
 lib/helpers/populate/assignVals.js | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 0eef697fc85..0697b303040 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -245,9 +245,6 @@ function valueFilter(val, assignmentOpts, populateOptions, allIds) {
     return val;
   }
 
-  if (populateOptions.justOne === true) {
-    return val == null ? transform(val, allIds) : transform(null, allIds);
-  }
   if (populateOptions.justOne === false) {
     return [];
   }

From c919931b7bbfbbbf77942258312368b6a4cef615 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 14 Apr 2021 17:55:10 -0400
Subject: [PATCH 1899/2348] made requested changes

---
 lib/model.js                |  2 +-
 test/model.populate.test.js | 49 ++-----------------------------------
 2 files changed, 3 insertions(+), 48 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 704b584eb66..c75ce339af9 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4548,7 +4548,7 @@ function _assign(model, vals, mod, assignmentOpts) {
   let val;
 
   // Clone because `assignRawDocsToIdStructure` will mutate the array
-  let allIds = utils.clone(mod.allIds);
+  const allIds = utils.clone(mod.allIds);
   // optimization:
   // record the document positions as returned by
   // the query result.
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index eea0e2d44d0..b2a756d0481 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10246,12 +10246,10 @@ describe('model: populate:', function() {
       yield aBook2.save();
 
       const populateOptions = [{
-        path: 'contributors.author', // *Note the array of objects - regular objects work as expected
+        path: 'contributors.author',
         model: 'authors',
         select: '_id name'
       }];
-
-      // Get the books and make book2 author in contributors just an id instead of an object
       const populatedBooks = (yield Books.find().populate(populateOptions)).map(aBook => {
         aBook = aBook.toObject();
         if (!aBook._id.equals(aBook1.id)) {
@@ -10260,51 +10258,8 @@ describe('model: populate:', function() {
         return aBook;
       });
 
-      // console.log('populatedBooks = ' + util.inspect(populatedBooks, false, null, true))
-      // after population and some manipulation, populatedBooks array:
-      /* const populatedBooks = [{
-          _id: aBook1.id,
-          name: aBook1.name
-          contributors: [{
-              _id: ObjectId
-              author: {
-                  _id: anAuthor.id,
-                  name: anAuthor.name
-              }
-          }]
-      }, {
-          _id: aBook2.id,
-          name: aBook2.name
-          contributors: [{
-              _id: ObjectId
-              author: anAuthor.id
-          }]
-      }]
-      */
-      // now, we try to populate the array to get the remaining author that was not previously populated for aBook2
       const populatedBooksAgain = yield Books.populate(populatedBooks, populateOptions);
-      // console.log('populatedBooksAgain = ' + util.inspect(populatedBooks, false, null, true))
-
-      // after population, populatedBooksAgain array:
-      /* const populatedBooksAgain = [{
-          _id: aBook1.id,
-          name: aBook1.name
-          contributors: [{
-              _id: ObjectId
-              author: null //*this should NOT be null - it should be the same object going into populate (and it was in 5.2.10)
-          }]
-      }, {
-          _id: aBook2.id,
-          name: aBook2.name
-          contributors: [{
-              _id: ObjectId
-              author: {
-                  _id: anAuthor.id,
-                  name: anAuthor.name
-              }
-          }]
-      }]
-      */
+
       assert.equal(populatedBooksAgain[0].contributors[0].author.name, 'Author1');
     });
   });

From f5a3a01def9c5d9d01556a605844a2809d3d6e21 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 15 Apr 2021 10:28:45 -0400
Subject: [PATCH 1900/2348] linter fix

---
 test/model.populate.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index eef362c656a..289f88f8b18 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10258,7 +10258,7 @@ describe('model: populate:', function() {
         }
         return aBook;
       });
-      
+
       const populatedBooksAgain = yield Books.populate(populatedBooks, populateOptions);
 
       assert.equal(populatedBooksAgain[0].contributors[0].author.name, 'Author1');

From 725d6c62b2aa339f78f6041e8185868b2e5ce00a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 15 Apr 2021 13:55:59 -0400
Subject: [PATCH 1901/2348] chore: release 5.12.4

---
 History.md   | 19 +++++++++++++++++++
 package.json |  2 +-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index cd3daf62008..f8b565887ce 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,22 @@
+5.12.4 / 2021-04-15
+===================
+ * fix: upgrade mongodb driver -> 3.6.6 #10079
+ * fix: store fields set with select:false at schema-level when saving a new document #10101 [ptantiku](https://github.com/ptantiku)
+ * fix(populate): avoid turning already populated field to null when populating an existing lean document #10068 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(populate): correctly populate lean subdocs with `_id` property #10069
+ * fix(model): insertedDocs may contain docs that weren't inserted #10098 [olnazx](https://github.com/olnazx)
+ * fix(schemaType): make type Mixed cast error objects to pojos #10131 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(populate): support populating embedded discriminators in nested arrays #9984
+ * fix(populate): handle populating map paths using trailing `.$*` #10123
+ * fix(populate): allow returning primitive from `transform()` function for single conventional populate #10064
+ * fix(index.d.ts): allow generic classes of `T` to use `T & Document` internally #10046
+ * fix(index.d.ts): allow `$pull` with `$` paths #10075
+ * fix(index.d.ts): use correct `Date` type for `$currentDate` #10058
+ * fix(index.d.ts): add missing asyncInterator to Query type def #10094 [borfig](https://github.com/borfig)
+ * fix(index.d.ts): allow RHS of `$unset` properties to be any value #10066
+ * fix(index.d.ts): allow setting SchemaType `index` property to a string #10077
+ * refactor(index.d.ts): move discriminator() to common interface #10109 [LoneRifle](https://github.com/LoneRifle)
+
 5.12.3 / 2021-03-31
 ===================
  * fix: avoid setting schema-level collation on text indexes #10044 [IslandRhythms](https://github.com/IslandRhythms)
diff --git a/package.json b/package.json
index c54a50004ca..761618de650 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.3",
+  "version": "5.12.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 86524c786251e6a4d7fd705517ec9b463e9eba83 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 15 Apr 2021 20:50:19 -0400
Subject: [PATCH 1902/2348] fix(index.d.ts): allow `type: Boolean` in Schema
 definitions

Fix #10085
---
 index.d.ts                | 6 ++++--
 test/typescript/schema.ts | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e8ae77746dc..b436578fafa 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1208,10 +1208,12 @@ declare module 'mongoose' {
     virtualpath(name: string): VirtualType | null;
   }
 
-  type SchemaDefinitionWithBuiltInClass<T extends number | string | Function> = T extends number
+  type SchemaDefinitionWithBuiltInClass<T extends number | string | boolean | Function> = T extends number
     ? (typeof Number | 'number' | 'Number' | typeof Schema.Types.Number)
     : T extends string
     ? (typeof String | 'string' | 'String' | typeof Schema.Types.String)
+    : T extends boolean
+    ? (typeof Boolean | 'boolean' | 'Boolean' | typeof Schema.Types.Boolean)
     : (Function | string);
 
   type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function
@@ -1395,7 +1397,7 @@ declare module 'mongoose' {
 
   export class SchemaTypeOptions<T> {
     type?:
-      T extends string | number | Function ? SchemaDefinitionWithBuiltInClass<T> :
+      T extends string | number | boolean | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema ? T :
       T extends object[] ? Schema<Document<Unpacked<T>>>[] :
       T | typeof SchemaType | Schema;
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index bdb6446c9f2..c1e5404d56e 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -95,7 +95,7 @@ async function gh9857() {
 
   const schemaDefinition: UserSchemaDefinition = {
     name: { type: String },
-    active: Boolean,
+    active: { type: Boolean },
     points: Number
   };
 

From 6d962f4328d6955baffc36f282e44e66f63b3e0e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 15 Apr 2021 21:16:51 -0400
Subject: [PATCH 1903/2348] fix(index.d.ts): allow numbers as discriminator
 names

Fix #10115
---
 index.d.ts | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b436578fafa..ea11c8bb67b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -601,8 +601,8 @@ declare module 'mongoose' {
 
   interface AcceptsDiscriminator {
     /** Adds a discriminator type. */
-    discriminator<D extends Document>(name: string, schema: Schema<D>, value?: string): Model<D>;
-    discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
+    discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
+    discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
   }
 
   export const Model: Model<any>;
@@ -1607,8 +1607,8 @@ declare module 'mongoose' {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator<D extends Document>(name: string, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
+        discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
 
         /**
          * Adds an enum validator if this is an array of strings or numbers. Equivalent to
@@ -1664,8 +1664,8 @@ declare module 'mongoose' {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator<D extends Document>(name: string, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T extends Document, U extends Model<T>>(name: string, schema: Schema<T, U>, value?: string): U;
+        discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
 
         /** The schema used for documents in this array */
         schema: Schema;

From 854374b2f48eda17782a99fff839fe9501f71a6f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 15 Apr 2021 21:51:04 -0400
Subject: [PATCH 1904/2348] docs(schema): fix incorrect links from schema API
 docs

Fix #10111
---
 lib/schema.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 994c9d8c7d6..6c4cd1f1545 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1458,7 +1458,7 @@ Schema.prototype.plugin = function(fn, opts) {
  *     fizz.purr();
  *     fizz.scratch();
  *
- * NOTE: `Schema.method()` adds instance methods to the `Schema.methods` object. You can also add instance methods directly to the `Schema.methods` object as seen in the [guide](./guide.html#methods)
+ * NOTE: `Schema.method()` adds instance methods to the `Schema.methods` object. You can also add instance methods directly to the `Schema.methods` object as seen in the [guide](/docs/guide.html#methods)
  *
  * @param {String|Object} method name
  * @param {Function} [fn]
@@ -1862,9 +1862,9 @@ function _deletePath(schema, name) {
 /**
  * Loads an ES6 class into a schema. Maps [setters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set) + [getters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get), [static methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static),
  * and [instance methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Class_body_and_method_definitions)
- * to schema [virtuals](http://mongoosejs.com/docs/guide.html#virtuals),
- * [statics](http://mongoosejs.com/docs/guide.html#statics), and
- * [methods](http://mongoosejs.com/docs/guide.html#methods).
+ * to schema [virtuals](/docs/guide.html#virtuals),
+ * [statics](/docs/guide.html#statics), and
+ * [methods](/docs/guide.html#methods).
  *
  * ####Example:
  *

From 7b2b1bff6e8dcd79c0d6dccb9eaf77035555a8bc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 13:00:19 -0400
Subject: [PATCH 1905/2348] fix(populate): handle populating paths on documents
 with discriminator keys that point to non-existent discriminators

Fix #10082
---
 .../populate/getModelsMapForPopulate.js       | 37 +++++++++----------
 lib/helpers/populate/getSchemaTypes.js        |  2 +-
 test/model.discriminator.querying.test.js     | 37 +++++++++++++++++++
 3 files changed, 55 insertions(+), 21 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 9e55c45d542..5dcdfd5d155 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -30,7 +30,6 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
   let currentOptions;
   let modelNames;
   let modelName;
-  let modelForFindSchema;
 
   const originalModel = options.model;
   let isVirtual = false;
@@ -405,28 +404,26 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     } else {
       let modelForCurrentDoc = model;
       let schemaForCurrentDoc;
-
-      if (!schema && discriminatorKey) {
-        modelForFindSchema = utils.getValue(discriminatorKey, doc);
-        if (modelForFindSchema) {
-          // `modelForFindSchema` is the discriminator value, so we might need
-          // find the discriminated model name
-          const discriminatorModel = getDiscriminatorByValue(model, modelForFindSchema);
-          if (discriminatorModel != null) {
-            modelForCurrentDoc = discriminatorModel;
-          } else {
-            try {
-              modelForCurrentDoc = model.db.model(modelForFindSchema);
-            } catch (error) {
-              return error;
-            }
+      let discriminatorValue;
+
+      if (!schema && discriminatorKey && (discriminatorValue = utils.getValue(discriminatorKey, doc))) {
+        // `modelNameForFind` is the discriminator value, so we might need
+        // find the discriminated model name
+        const discriminatorModel = getDiscriminatorByValue(model, discriminatorValue) || model;
+        if (discriminatorModel != null) {
+          modelForCurrentDoc = discriminatorModel;
+        } else {
+          try {
+            modelForCurrentDoc = model.db.model(discriminatorValue);
+          } catch (error) {
+            return error;
           }
+        }
 
-          schemaForCurrentDoc = modelForCurrentDoc.schema._getSchema(options.path);
+        schemaForCurrentDoc = modelForCurrentDoc.schema._getSchema(options.path);
 
-          if (schemaForCurrentDoc && schemaForCurrentDoc.caster) {
-            schemaForCurrentDoc = schemaForCurrentDoc.caster;
-          }
+        if (schemaForCurrentDoc && schemaForCurrentDoc.caster) {
+          schemaForCurrentDoc = schemaForCurrentDoc.caster;
         }
       } else {
         schemaForCurrentDoc = schema;
diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index fdad82641f0..c500d802d87 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -139,7 +139,7 @@ module.exports = function getSchemaTypes(schema, doc, path) {
           if (type.schema.discriminators) {
             const discriminatorPaths = [];
             for (const discriminatorName of Object.keys(type.schema.discriminators)) {
-              const _schema = type.schema.discriminators[discriminatorName];
+              const _schema = type.schema.discriminators[discriminatorName] || type.schema;
               const ret = search(parts.slice(p), _schema, null, nestedPath.concat(parts.slice(0, p)));
               if (ret != null) {
                 discriminatorPaths.push(ret);
diff --git a/test/model.discriminator.querying.test.js b/test/model.discriminator.querying.test.js
index 4cd246f3b3e..a1bbf6155e5 100644
--- a/test/model.discriminator.querying.test.js
+++ b/test/model.discriminator.querying.test.js
@@ -871,6 +871,43 @@ describe('model', function() {
           assert.ok(events[0].surveys[0] instanceof Survey);
         });
       });
+
+      it('correctly populates doc with nonexistent discriminator key (gh-10082)', function() {
+        const foodSchema = Schema({ name: String, animal: String });
+        const Food = db.model('Food', foodSchema);
+
+        const animalSchema = Schema({ type: String }, {
+          discriminatorKey: 'type',
+          toJSON: { virtuals: true },
+          toObject: { virtuals: true }
+        });
+        const catSchema = Schema({ catYears: Number });
+        animalSchema.virtual('foods', {
+          ref: 'Food',
+          localField: 'type',
+          foreignField: 'animal',
+          justOne: false
+        });
+        const Animal = db.model('Animal', animalSchema);
+        Animal.discriminator('cat', catSchema);
+        // const Rabbit = Animal.discriminator('rabbit', rabbitSchema);
+
+        return co(function*() {
+          yield Promise.all([
+            new Food({ name: 'Cat Food', animal: 'cat' }).save(),
+            new Food({ name: 'Rabbit Food', animal: 'rabbit' }).save()
+          ]);
+          yield Animal.collection.insertOne({ type: 'cat', catYears: 4 });
+          yield Animal.collection.insertOne({ type: 'rabbit' }); // <-- "rabbit" has no discriminator
+
+          const cat = yield Animal.findOne({ type: 'cat' }).populate('foods');
+          const rabbit = yield Animal.findOne({ type: 'rabbit' }).populate('foods');
+          assert.equal(cat.foods.length, 1);
+          assert.equal(cat.foods[0].name, 'Cat Food');
+          assert.equal(rabbit.foods.length, 1);
+          assert.equal(rabbit.foods[0].name, 'Rabbit Food');
+        });
+      });
     });
 
     describe('deleteOne and deleteMany (gh-8471)', function() {

From dad2e20d70f8328f8675cafeb89c0f785bd08454 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 14:22:03 -0400
Subject: [PATCH 1906/2348] fix(connection): pull correct `autoCreate` value
 from Mongoose global when creating new model before calling `connect()`

Fix #10091
---
 lib/connection.js | 9 +++++++--
 lib/index.js      | 3 ++-
 lib/model.js      | 4 +++-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index 2b90e53719c..e562c3e4794 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -58,7 +58,7 @@ function Connection(base) {
   this.base = base;
   this.collections = {};
   this.models = {};
-  this.config = { autoIndex: true };
+  this.config = {};
   this.replica = false;
   this.options = null;
   this.otherDbs = []; // FIXME: To be replaced with relatedDbs
@@ -727,6 +727,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
 
   if (options) {
     options = utils.clone(options);
+
     const autoIndex = options.config && options.config.autoIndex != null ?
       options.config.autoIndex :
       options.autoIndex;
@@ -1116,7 +1117,11 @@ Connection.prototype.onClose = function(force) {
  */
 
 Connection.prototype.collection = function(name, options) {
-  options = options ? utils.clone(options) : {};
+  const defaultOptions = {
+    autoIndex: this.config.autoIndex != null ? this.config.autoIndex : this.base.options.autoIndex,
+    autoCreate: this.config.autoCreate != null ? this.config.autoCreate : this.base.options.autoCreate
+  };
+  options = Object.assign({}, defaultOptions, options ? utils.clone(options) : {});
   options.$wasForceClosed = this.$wasForceClosed;
   if (!(name in this.collections)) {
     this.collections[name] = new Collection(name, this, options);
diff --git a/lib/index.js b/lib/index.js
index c46cf543585..37689fe9c47 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -69,7 +69,8 @@ function Mongoose(options) {
   this.events = new EventEmitter();
   // default global options
   this.options = Object.assign({
-    pluralization: true
+    pluralization: true,
+    autoIndex: true
   }, options);
   const conn = this.createConnection(); // default connection
   conn.models = this.models;
diff --git a/lib/model.js b/lib/model.js
index 99e3825aca3..918fc353dc4 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4765,9 +4765,11 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
   const collectionOptions = {
     schemaUserProvidedOptions: _userProvidedOptions,
     capped: schema.options.capped,
-    autoCreate: schema.options.autoCreate,
     Promise: model.base.Promise
   };
+  if (schema.options.autoCreate !== void 0) {
+    collectionOptions.autoCreate = schema.options.autoCreate;
+  }
 
   model.prototype.collection = connection.collection(
     collectionName,

From c90140f210906e121850671b20be800e2541c55a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 14:33:43 -0400
Subject: [PATCH 1907/2348] fix(index.d.ts): allow `any` for `$push` to allow
 `$push` with positional operator

Re: #10122
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index ea11c8bb67b..849d0914500 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2300,7 +2300,7 @@ declare module 'mongoose' {
     $addToSet?: mongodb.SetFields<TSchema>;
     $pop?: mongodb.OnlyFieldsOfType<TSchema, ReadonlyArray<any>, 1 | -1>;
     $pull?: PullOperator<TSchema>;
-    $push?: mongodb.PushOperator<TSchema>;
+    $push?: mongodb.PushOperator<TSchema> | any;
     $pullAll?: mongodb.PullAllOperator<TSchema>;
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-bitwise/ */

From e2b7553b60b0de30525ed1d2c17b1cbde2a4aef6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 14:41:19 -0400
Subject: [PATCH 1908/2348] fix(index.d.ts): support legacy 2nd param callback
 syntax for `deleteOne()`, `deleteMany()`

Fix #10122
---
 index.d.ts | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 849d0914500..8cb4be7f50c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -443,11 +443,13 @@ declare module 'mongoose' {
 
     /** Removes this document from the db. */
     delete(options?: QueryOptions): QueryWithHelpers<any, this, TQueryHelpers>;
-    delete(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
+    delete(options: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
+    delete(cb: (err: CallbackError, res: any) => void): void;
 
     /** Removes this document from the db. */
     deleteOne(options?: QueryOptions): QueryWithHelpers<any, this, TQueryHelpers>;
-    deleteOne(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
+    deleteOne(options: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
+    deleteOne(cb: (err: CallbackError, res: any) => void): void;
 
     /** Takes a populated field and returns it to its unpopulated state. */
     depopulate(path: string): this;
@@ -679,6 +681,8 @@ declare module 'mongoose' {
      * regardless of the `single` option.
      */
     deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
@@ -686,6 +690,8 @@ declare module 'mongoose' {
      * `single` option.
      */
     deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
@@ -1926,6 +1932,8 @@ declare module 'mongoose' {
      * collection, regardless of the value of `single`.
      */
     deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    deleteMany(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    deleteMany(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as a `deleteOne()` operation. Works like
@@ -1933,6 +1941,8 @@ declare module 'mongoose' {
      * option.
      */
     deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    deleteOne(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    deleteOne(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
     distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers>;

From 998ef5439fda6e18f5e395c183e17a94822747a4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 20:19:19 -0400
Subject: [PATCH 1909/2348] fix(populate): clear out dangling pointers to
 populated docs so query cursor with populate() can garbage collect populated
 subdocs

Fix #9864
---
 lib/document.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/document.js b/lib/document.js
index 34f1838e1a6..0c6f3c138f1 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -589,6 +589,7 @@ Document.prototype.$__init = function(doc, opts) {
         }
         child.$__.parent = this;
       }
+      item._childDocs = [];
     }
   }
 

From 61d24d41e00454fccda9bf1e69730d2bdbe700c9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 20:42:38 -0400
Subject: [PATCH 1910/2348] fix(index.d.ts): allow passing array of aggregation
 pipeline stages to `updateOne()` and `updateMany()`

Fix #10095
---
 index.d.ts                 | 10 +++++++++-
 lib/model.js               |  4 ++--
 lib/query.js               |  4 ++--
 test/typescript/queries.ts |  1 +
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 8cb4be7f50c..a0c6bc3e005 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2319,7 +2319,15 @@ declare module 'mongoose' {
     };
   };
 
-  export type UpdateQuery<T> = _UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>;
+  type UpdateWithAggregationPipeline = UpdateAggregationStage[];
+  type UpdateAggregationStage = { $addFields: any } |
+    { $set: any } |
+    { $project: any } |
+    { $unset: any } |
+    { $replaceRoot: any } |
+    { $replaceWith: any };
+
+  export type UpdateQuery<T> = (_UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>) | UpdateWithAggregationPipeline;
 
   type _AllowStringsForIds<T> = {
     [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;
diff --git a/lib/model.js b/lib/model.js
index 918fc353dc4..b44a436b8d5 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3681,7 +3681,7 @@ Model.update = function update(conditions, doc, options, callback) {
  * - `updateMany()`
  *
  * @param {Object} filter
- * @param {Object} doc
+ * @param {Object|Array} update
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
@@ -3719,7 +3719,7 @@ Model.updateMany = function updateMany(conditions, doc, options, callback) {
  * - `updateOne()`
  *
  * @param {Object} filter
- * @param {Object} doc
+ * @param {Object|Array} update
  * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Boolean|String} [options.strict] overwrites the schema's [strict mode option](http://mongoosejs.com/docs/guide.html#strict)
  * @param {Boolean} [options.upsert=false] if true, and no documents found, insert a new document
diff --git a/lib/query.js b/lib/query.js
index b61456d8557..e674f0edf6f 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4047,7 +4047,7 @@ Query.prototype.update = function(conditions, doc, options, callback) {
  * - `updateMany()`
  *
  * @param {Object} [filter]
- * @param {Object} [doc] the update command
+ * @param {Object|Array} [update] the update command
  * @param {Object} [options]
  * @param {Boolean} [options.multipleCastError] by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
@@ -4113,7 +4113,7 @@ Query.prototype.updateMany = function(conditions, doc, options, callback) {
  * - `updateOne()`
  *
  * @param {Object} [filter]
- * @param {Object} [doc] the update command
+ * @param {Object|Array} [update] the update command
  * @param {Object} [options]
  * @param {Boolean} [options.multipleCastError] by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.
  * @param {Boolean} [options.omitUndefined=false] If true, delete any properties whose value is `undefined` when casting an update. In other words, if this is set, Mongoose will delete `baz` from the update in `Model.updateOne({}, { foo: 'bar', baz: undefined })` before sending the update to the server.
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index df22aa8b41d..ffb54e6ad3e 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -79,6 +79,7 @@ const update = Math.random() > 0.5 ? { $unset: { 'docs.0': 1 } } : { age: 55 };
 Test.findOneAndUpdate({ name: 'test' }, update);
 
 Test.findOneAndUpdate({ name: 'test' }, { $currentDate: { endDate: true } });
+Test.findOneAndUpdate({ name: 'test' }, [{ $set: { endDate: true } }]);
 
 Test.findByIdAndUpdate({ name: 'test' }, { name: 'test2' }, (err, doc) => console.log(doc));
 

From 95f8fe7d3550600ca7221e32b6ab654a304a51a6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 20:54:54 -0400
Subject: [PATCH 1911/2348] docs(mongoose): make `useCreateIndex` always
 `false` in docs

Fix #10033
---
 lib/connection.js                | 2 +-
 lib/index.js                     | 3 ++-
 test/model.discriminator.test.js | 1 -
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index e562c3e4794..a0638f27812 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -662,7 +662,7 @@ Connection.prototype.onOpen = function() {
  * @param {Number} [options.heartbeatFrequencyMS] If `useUnifiedTopology = true`, the MongoDB driver sends a heartbeat every `heartbeatFrequencyMS` to check on the status of the connection. A heartbeat is subject to `serverSelectionTimeoutMS`, so the MongoDB driver will retry failed heartbeats for up to 30 seconds by default. Mongoose only emits a `'disconnected'` event after a heartbeat has failed, so you may want to decrease this setting to reduce the time between when your server goes down and when Mongoose emits `'disconnected'`. We recommend you do **not** set this setting below 1000, too many heartbeats can lead to performance degradation.
  * @param {Boolean} [options.autoIndex=true] Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.
  * @param {Boolean} [options.useNewUrlParser=false] False by default. Set to `true` to opt in to the MongoDB driver's new URL parser logic.
- * @param {Boolean} [options.useCreateIndex=true] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
+ * @param {Boolean} [options.useCreateIndex=false] Mongoose-specific option. If `true`, this connection will use [`createIndex()` instead of `ensureIndex()`](/docs/deprecations.html#ensureindex) for automatic index builds via [`Model.init()`](/docs/api.html#model_Model.init).
  * @param {Boolean} [options.useFindAndModify=true] True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
  * @param {Number} [options.reconnectTries=30] If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
  * @param {Number} [options.reconnectInterval=1000] See `reconnectTries` option above.
diff --git a/lib/index.js b/lib/index.js
index 37689fe9c47..31ebcc01e15 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -70,7 +70,8 @@ function Mongoose(options) {
   // default global options
   this.options = Object.assign({
     pluralization: true,
-    autoIndex: true
+    autoIndex: true,
+    useCreateIndex: false
   }, options);
   const conn = this.createConnection(); // default connection
   conn.models = this.models;
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 08ee207c06c..54c5e7e169b 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1677,7 +1677,6 @@ describe('model', function() {
       });
 
       map = yield Map.findById(map).populate({ path: 'tiles.enemy' });
-      console.log(map.tiles);
       assert.equal(map.tiles[0][0].enemy.name, 'Bowser');
     });
   });

From 937cb2473487f987213c1ce1614082db79b9dbc4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Apr 2021 21:35:51 -0400
Subject: [PATCH 1912/2348] fix(populate): handle populating underneath
 document array when document array property doesn't exist in db

Fix #10003
---
 lib/helpers/populate/assignVals.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 53d7bf2aa35..0e556b33536 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -148,7 +148,7 @@ module.exports = function assignVals(o) {
         // See gh-8342, gh-8455
         const schematype = originalSchema._getSchema(curPath);
         if (valueToSet == null && schematype != null && schematype.$isMongooseArray) {
-          return;
+          break;
         }
         cur[parts[j]] = {};
       }
@@ -156,7 +156,7 @@ module.exports = function assignVals(o) {
       // If the property in MongoDB is a primitive, we won't be able to populate
       // the nested path, so skip it. See gh-7545
       if (typeof cur !== 'object') {
-        return;
+        break;
       }
     }
     if (docs[i].$__) {

From d5b7e25d8a117af3cc23c58b56147a05879a783c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 19 Apr 2021 11:06:17 -0400
Subject: [PATCH 1913/2348] docs: update license copyright

Fix #9430
---
 LICENSE.md | 3 ++-
 index.pug  | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/LICENSE.md b/LICENSE.md
index 14cdf56d4cf..54b4a4c6c16 100644
--- a/LICENSE.md
+++ b/LICENSE.md
@@ -1,6 +1,7 @@
 # MIT License
 
-Copyright (c) 2010 LearnBoost <dev@learnboost.com>
+Copyright (c) 2010-2013 LearnBoost <dev@learnboost.com>
+Copyright (c) 2013-2021 Automattic
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/index.pug b/index.pug
index b75c9a89568..551cc80919e 100644
--- a/index.pug
+++ b/index.pug
@@ -85,7 +85,7 @@ html(lang='en')
       }
 
   body
-    a#forkbanner(href="http://github.com/learnboost/mongoose")
+    a#forkbanner(href="http://github.com/Automattic/mongoose")
       img(style="position: absolute; top: 0; right: 0; border: 0;", src="https://s3.amazonaws.com/github/ribbons/forkme_right_gray_6d6d6d.png", alt="Fork me on GitHub")
     #wrap.homepage
       #header

From 98519de1e8f3144353e95400e89adb3ffcbd7156 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 19 Apr 2021 11:10:57 -0400
Subject: [PATCH 1914/2348] chore: release 5.12.5

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f8b565887ce..eaf511d14dc 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.12.5 / 2021-04-19
+===================
+ * fix(populate): handle populating underneath document array when document array property doesn't exist in db #10003
+ * fix(populate): clear out dangling pointers to populated docs so query cursor with populate() can garbage collect populated subdocs #9864
+ * fix(connection): pull correct `autoCreate` value from Mongoose global when creating new model before calling `connect()` #10091
+ * fix(populate): handle populating paths on documents with discriminator keys that point to non-existent discriminators #10082
+ * fix(index.d.ts): allow numbers as discriminator names #10115
+ * fix(index.d.ts): allow `type: Boolean` in Schema definitions #10085
+ * fix(index.d.ts): allow passing array of aggregation pipeline stages to `updateOne()` and `updateMany()` #10095
+ * fix(index.d.ts): support legacy 2nd param callback syntax for `deleteOne()`, `deleteMany()` #10122
+ * docs(mongoose): make `useCreateIndex` always `false` in docs #10033
+ * docs(schema): fix incorrect links from schema API docs #10111
+
 5.12.4 / 2021-04-15
 ===================
  * fix: upgrade mongodb driver -> 3.6.6 #10079
diff --git a/package.json b/package.json
index 761618de650..bc444a018c1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.4",
+  "version": "5.12.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From ba9ac2e756b0143b3b1d3f040fcc25e5483bb067 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 19 Apr 2021 13:08:18 -0400
Subject: [PATCH 1915/2348] Update models.ts

---
 test/typescript/models.ts | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index b6917f876e8..992fe7fc032 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -1,4 +1,4 @@
-import { Schema, Document, Model, connection, model } from 'mongoose';
+import { Schema, Document, Model, connection, model, mongoose } from 'mongoose';
 
 function conventionalSyntax(): void {
   interface ITest extends Document {
@@ -64,6 +64,30 @@ function schemaStaticsWithoutGenerics() {
   UserModel.static1();
 }
 
+function gh10074() {
+  interface IDog {
+    breed: string;
+    name: string;
+    age: number;
+  }
+
+  type IDogDocument = IDog & Types.Document;
+
+  const DogSchema = new Schema<IDogDocument>(
+    {
+      breed: { type: String },
+      name: { type: String },
+      age: { type: Number }
+    }
+  );
+
+  const Dog = mongoose.model<IDogDocument, Model<IDogDocument>>('dog', DogSchema);
+
+  const rex = new Dog({
+    // type inference here
+  });
+}
+
 const ExpiresSchema = new Schema({
   ttl: {
     type: Date,

From c8c50c3e5ba76145692003c602dd2d373ae0f8bd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 19 Apr 2021 15:36:23 -0400
Subject: [PATCH 1916/2348] chore: update opencollective sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index 551cc80919e..8bfe2c76f71 100644
--- a/index.pug
+++ b/index.pug
@@ -169,9 +169,6 @@ html(lang='en')
               <a rel="sponsored" href="https://localizejs.com/">
                 <img class="sponsor" src="https://images.opencollective.com/localize/bb2cd4d/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://www.codefirst.co.uk/">
-                <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fdde88120-e914-11e8-a662-278259d35390.png&height=100">
-              </a>
               <a rel="sponsored" href="https://www.dontpayfull.com/">
                 <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F84c4ba80-1955-11e8-8343-278614155b3e.png&height=100" style="height:100px">
               </a>
@@ -325,9 +322,6 @@ html(lang='en')
               <a rel="sponsored" href="https://nettikasinot247.fi/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-24-7/c51fe6a/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://www.kasinosivu.com/pikakasinot/">
-                <img class="sponsor" src="https://images.opencollective.com/pikakasinot/5ef0793/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://goread.io/buy-instagram-likes">
                 <img class="sponsor" src="https://goread.io/assets/images/Goreadlogo.png" style="height: 100px" alt="Buy Instagram Likes">
               </a>

From b8e33061782e24dce5fb0caa3ed4ac9d5a965d62 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 19 Apr 2021 18:02:00 -0400
Subject: [PATCH 1917/2348] better understanding

---
 lib/document.js         |  7 ++++---
 lib/model.js            | 19 ++++++++++---------
 test/versioning.test.js | 23 +++++++++++++++++++++++
 3 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0c6f3c138f1..67b0a55941b 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2904,6 +2904,7 @@ Document.prototype.$__reset = function reset() {
     });
 
   // clear atomics
+  // console.log(new Error().stack);
   this.$__dirty().forEach(function(dirt) {
     const type = dirt.value;
 
@@ -2981,7 +2982,6 @@ Document.prototype.$__dirty = function() {
       schema: _this.$__path(path)
     };
   });
-
   // gh-2558: if we had to set a default and the value is not undefined,
   // we have to save as well
   all = all.concat(this.$__.activePaths.map('default', function(path) {
@@ -3025,9 +3025,10 @@ Document.prototype.$__dirty = function() {
       top.value[arrayAtomicsSymbol].$set = top.value;
     }
   });
-
   top = lastPath = null;
-  return minimal;
+  console.log('hello');
+  // console.log(new Error().stack);
+  return minimal; // This is disappearing on the third execution for whatever reason.
 };
 
 /**
diff --git a/lib/model.js b/lib/model.js
index b44a436b8d5..cc96d3a4edf 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -225,6 +225,7 @@ function _applyCustomWhere(doc, where) {
  */
 
 Model.prototype.$__handleSave = function(options, callback) {
+  // console.log(new Error().stack);
   const _this = this;
   let saveOptions = {};
 
@@ -281,7 +282,6 @@ Model.prototype.$__handleSave = function(options, callback) {
 
       callback(null, ret);
     });
-
     this.$__reset();
     _setIsNew(this, false);
     // Make it possible to retry the insert
@@ -292,7 +292,8 @@ Model.prototype.$__handleSave = function(options, callback) {
     this.$__.inserting = false;
 
     const delta = this.$__delta();
-
+    // console.log('over here scoob');
+    console.log('this is the return value of delta from dirty', delta);
     if (delta) {
       if (delta instanceof MongooseError) {
         callback(delta);
@@ -333,7 +334,7 @@ Model.prototype.$__handleSave = function(options, callback) {
 
     // store the modified paths before the document is reset
     this.$__.modifiedPaths = this.modifiedPaths();
-
+    // need to prevent this from being called early
     this.$__reset();
 
     _setIsNew(this, false);
@@ -390,7 +391,6 @@ Model.prototype.$__save = function(options, callback) {
           this.$__setValue(key, version + 1);
         }
       }
-
       if (result != null && numAffected <= 0) {
         this.$__undoReset();
         error = new DocumentNotFoundError(result.$where,
@@ -474,11 +474,9 @@ Model.prototype.save = function(options, fn) {
   if (options.hasOwnProperty('session')) {
     this.$session(options.session);
   }
-
   this.$__.$versionError = generateVersionError(this, this.modifiedPaths());
 
   fn = this.constructor.$handleCallbackError(fn);
-
   return this.constructor.db.base._promiseOrCallback(fn, cb => {
     cb = this.constructor.$wrapCallback(cb);
 
@@ -667,10 +665,15 @@ function handleAtomics(self, where, delta, data, value) {
 
 Model.prototype.$__delta = function() {
   const dirty = this.$__dirty();
+  console.log('this is dirty', dirty);
+  // console.log(new Error().stack);
+  // console.log(this);
+  // console.log(this.$__.$options);
+  // console.log('hello');
   if (!dirty.length && VERSION_ALL !== this.$__.version) {
+    // console.log('there');
     return;
   }
-
   const where = {};
   const delta = {};
   const len = dirty.length;
@@ -683,7 +686,6 @@ Model.prototype.$__delta = function() {
   if (get(where, '_id.$__', null) != null) {
     where._id = where._id.toObject({ transform: false, depopulate: true });
   }
-
   for (; d < len; ++d) {
     const data = dirty[d];
     let value = data.value;
@@ -716,7 +718,6 @@ Model.prototype.$__delta = function() {
     }
 
     if (divergent.length) continue;
-
     if (value === undefined) {
       operand(this, where, delta, data, 1, '$unset');
     } else if (value === null) {
diff --git a/test/versioning.test.js b/test/versioning.test.js
index 7c4efd9af24..75167491ee2 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -540,6 +540,29 @@ describe('versioning', function() {
     });
   });
 
+  it('should persist correctly when optimisticConcurrency is true gh-10128', function() {
+    const thingSchema = new Schema({ price: Number }, { optimisticConcurrency: true });
+    const Thing = db.model('Thing', thingSchema);
+    return co(function*() {
+      const thing = yield Thing.create({ price: 1 });
+      yield thing.save();
+      assert.equal(thing.__v, 0);
+      const thing_1 = yield Thing.findById(thing.id);
+      const thing_2 = yield Thing.findById(thing.id); // this needs to throw an error
+      thing_1.set({ price: 2 });
+      yield thing_1.save();
+      assert.equal(thing_1.__v, 1);
+      thing_2.set({ price: 1 });
+      // thing_2.set({ price: 2 });
+      // yield thing_2.save();
+      const err = yield thing_2.save().then(() => null, err => err);
+      assert.ok(err);
+      // problem is thing_2 is not aware that price has changed and so
+      // when it wants to set it back, thing_2 thinks it is already 1 since
+      // that is what it had when it saved the value originally.
+    });
+  });
+
   describe('versioning is off', function() {
     it('when { safe: false } is set (gh-1520)', function(done) {
       const schema1 = new Schema({ title: String }, { safe: false });

From 588ed29865b79195ddf283541d32193771875957 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 20 Apr 2021 12:35:13 -0400
Subject: [PATCH 1918/2348] update

---
 lib/document.js | 2 --
 lib/model.js    | 6 ++----
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 67b0a55941b..a8853c793c6 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3026,8 +3026,6 @@ Document.prototype.$__dirty = function() {
     }
   });
   top = lastPath = null;
-  console.log('hello');
-  // console.log(new Error().stack);
   return minimal; // This is disappearing on the third execution for whatever reason.
 };
 
diff --git a/lib/model.js b/lib/model.js
index cc96d3a4edf..80547cf2b3d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -293,7 +293,7 @@ Model.prototype.$__handleSave = function(options, callback) {
 
     const delta = this.$__delta();
     // console.log('over here scoob');
-    console.log('this is the return value of delta from dirty', delta);
+    // console.log('this is the return value of delta from dirty', delta);
     if (delta) {
       if (delta instanceof MongooseError) {
         callback(delta);
@@ -353,7 +353,6 @@ Model.prototype.$__save = function(options, callback) {
         callback(error, this);
       });
     }
-
     let numAffected = 0;
     if (get(options, 'safe.w') !== 0 && get(options, 'w') !== 0) {
       // Skip checking if write succeeded if writeConcern is set to
@@ -369,7 +368,6 @@ Model.prototype.$__save = function(options, callback) {
           numAffected = result;
         }
       }
-
       // was this an update that required a version bump?
       if (this.$__.version && !this.$__.inserting) {
         const doIncrement = VERSION_INC === (VERSION_INC & this.$__.version);
@@ -665,7 +663,7 @@ function handleAtomics(self, where, delta, data, value) {
 
 Model.prototype.$__delta = function() {
   const dirty = this.$__dirty();
-  console.log('this is dirty', dirty);
+  // console.log('this is dirty', dirty);
   // console.log(new Error().stack);
   // console.log(this);
   // console.log(this.$__.$options);

From 5aabbf67a4917a0c3cd250962073438ccdffa138 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 20 Apr 2021 14:05:54 -0400
Subject: [PATCH 1919/2348] update

---
 lib/document.js | 2 +-
 lib/model.js    | 9 ++++-----
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index a8853c793c6..b06b282beab 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3026,7 +3026,7 @@ Document.prototype.$__dirty = function() {
     }
   });
   top = lastPath = null;
-  return minimal; // This is disappearing on the third execution for whatever reason.
+  return minimal;
 };
 
 /**
diff --git a/lib/model.js b/lib/model.js
index 80547cf2b3d..27669bebfd5 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -225,7 +225,6 @@ function _applyCustomWhere(doc, where) {
  */
 
 Model.prototype.$__handleSave = function(options, callback) {
-  // console.log(new Error().stack);
   const _this = this;
   let saveOptions = {};
 
@@ -258,7 +257,6 @@ Model.prototype.$__handleSave = function(options, callback) {
   if (this.isNew) {
     // send entire doc
     const obj = this.toObject(saveToObjectOptions);
-
     if ((obj || {})._id === void 0) {
       // documents must have an _id else mongoose won't know
       // what to update later if more changes are made. the user
@@ -368,14 +366,13 @@ Model.prototype.$__save = function(options, callback) {
           numAffected = result;
         }
       }
+      console.log(this.$__.version);
       // was this an update that required a version bump?
       if (this.$__.version && !this.$__.inserting) {
         const doIncrement = VERSION_INC === (VERSION_INC & this.$__.version);
         this.$__.version = undefined;
-
         const key = this.$__schema.options.versionKey;
         const version = this.$__getValue(key) || 0;
-
         if (numAffected <= 0) {
           // the update failed. pass an error back
           this.$__undoReset();
@@ -387,6 +384,7 @@ Model.prototype.$__save = function(options, callback) {
         // increment version if was successful
         if (doIncrement) {
           this.$__setValue(key, version + 1);
+          this.v = true;
         }
       }
       if (result != null && numAffected <= 0) {
@@ -398,6 +396,7 @@ Model.prototype.$__save = function(options, callback) {
         });
       }
     }
+    //put a statement here
     this.$__.saving = undefined;
     this.$__.savedState = {};
     this.emit('save', this, numAffected);
@@ -663,7 +662,7 @@ function handleAtomics(self, where, delta, data, value) {
 
 Model.prototype.$__delta = function() {
   const dirty = this.$__dirty();
-  // console.log('this is dirty', dirty);
+  console.log('this is dirty', dirty);
   // console.log(new Error().stack);
   // console.log(this);
   // console.log(this.$__.$options);

From 765dc9b7882a063791da8b3979455d42272586bc Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 20 Apr 2021 15:09:08 -0400
Subject: [PATCH 1920/2348] Update model.js

---
 lib/model.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 27669bebfd5..3185e17a8d1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -365,8 +365,9 @@ Model.prototype.$__save = function(options, callback) {
         } else {
           numAffected = result;
         }
+      } else{
+        // make a query here
       }
-      console.log(this.$__.version);
       // was this an update that required a version bump?
       if (this.$__.version && !this.$__.inserting) {
         const doIncrement = VERSION_INC === (VERSION_INC & this.$__.version);
@@ -384,7 +385,6 @@ Model.prototype.$__save = function(options, callback) {
         // increment version if was successful
         if (doIncrement) {
           this.$__setValue(key, version + 1);
-          this.v = true;
         }
       }
       if (result != null && numAffected <= 0) {

From e004f4a2242e3e079da306711b5bfc2ee0e79399 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 10:28:15 -0400
Subject: [PATCH 1921/2348] added test

---
 test/query.test.js | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/test/query.test.js b/test/query.test.js
index ae121ad2b6d..8aaab9a2ca7 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3788,4 +3788,27 @@ describe('Query', function() {
 
     assert.deepEqual(q.options.writeConcern, { w: 'majority', wtimeout: 1000 });
   });
+  it('no longer has the deprecation warning message with writeConcern gh-10083', function() {
+    const MySchema = new Schema(
+      {
+        _id: { type: Number, required: true },
+        op: { type: String, required: true },
+        size: { type: Number, required: true },
+        totalSize: { type: Number, required: true }
+      },
+      {
+        versionKey: false,
+        writeConcern: {
+          w: 'majority',
+          j: true,
+          wtimeout: 15000
+        }
+      }
+    );
+    const Test = db.model('Test', MySchema);
+    return co(function*() {
+      const entry = yield Test.create({ _id: 12345678, op: 'help', size: 54, totalSize: 104 });
+      yield entry.save();
+    });
+  });
 });

From 28802e4341c2d380c6775ff45cec2400b783552c Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 10:34:44 -0400
Subject: [PATCH 1922/2348] Update query.test.js

---
 test/query.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/query.test.js b/test/query.test.js
index 8aaab9a2ca7..e7064b2d7e8 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3789,7 +3789,7 @@ describe('Query', function() {
     assert.deepEqual(q.options.writeConcern, { w: 'majority', wtimeout: 1000 });
   });
   it('no longer has the deprecation warning message with writeConcern gh-10083', function() {
-    const MySchema = new Schema(
+    const MySchema = new mongoose.Schema(
       {
         _id: { type: Number, required: true },
         op: { type: String, required: true },

From 3a087ad7cb4d3ecc359b2fbab032a33b27214a79 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 11:22:33 -0400
Subject: [PATCH 1923/2348] rid of comments

---
 lib/document.js |  1 -
 lib/model.js    | 22 ++++++++++++----------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index b06b282beab..68cb7ae69d1 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2904,7 +2904,6 @@ Document.prototype.$__reset = function reset() {
     });
 
   // clear atomics
-  // console.log(new Error().stack);
   this.$__dirty().forEach(function(dirt) {
     const type = dirt.value;
 
diff --git a/lib/model.js b/lib/model.js
index 3185e17a8d1..01cddee11f5 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -290,8 +290,6 @@ Model.prototype.$__handleSave = function(options, callback) {
     this.$__.inserting = false;
 
     const delta = this.$__delta();
-    // console.log('over here scoob');
-    // console.log('this is the return value of delta from dirty', delta);
     if (delta) {
       if (delta instanceof MongooseError) {
         callback(delta);
@@ -318,7 +316,15 @@ Model.prototype.$__handleSave = function(options, callback) {
       });
     } else {
       const optionsWithCustomValues = Object.assign({}, options, saveOptions);
-      this.constructor.exists(this.$__where(), optionsWithCustomValues)
+      const where = this.$__where();
+      if (this.$__schema.options.optimisticConcurrency) {
+        const key = this.$__schema.options.versionKey;
+        const val = this.$__getValue(key);
+        if (val != null) {
+          where[key] = val;
+        }
+      }
+      this.constructor.exists(where, optionsWithCustomValues)
         .then((documentExists) => {
           if (!documentExists) {
             throw new DocumentNotFoundError(this.$__where(), this.constructor.modelName);
@@ -662,13 +668,7 @@ function handleAtomics(self, where, delta, data, value) {
 
 Model.prototype.$__delta = function() {
   const dirty = this.$__dirty();
-  console.log('this is dirty', dirty);
-  // console.log(new Error().stack);
-  // console.log(this);
-  // console.log(this.$__.$options);
-  // console.log('hello');
   if (!dirty.length && VERSION_ALL !== this.$__.version) {
-    // console.log('there');
     return;
   }
   const where = {};
@@ -811,7 +811,9 @@ Model.prototype.$__version = function(where, delta) {
 
   if (where === true) {
     // this is an insert
-    if (key) this.$__setValue(key, delta[key] = 0);
+    if (key) {
+      this.$__setValue(key, delta[key] = 0);
+    }
     return;
   }
 

From 5d62aa4b29f175fd407e94891bc148915a0699e0 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 11:23:23 -0400
Subject: [PATCH 1924/2348] Update model.js

---
 lib/model.js | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 01cddee11f5..cceb5598ae1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -371,8 +371,6 @@ Model.prototype.$__save = function(options, callback) {
         } else {
           numAffected = result;
         }
-      } else{
-        // make a query here
       }
       // was this an update that required a version bump?
       if (this.$__.version && !this.$__.inserting) {
@@ -402,7 +400,6 @@ Model.prototype.$__save = function(options, callback) {
         });
       }
     }
-    //put a statement here
     this.$__.saving = undefined;
     this.$__.savedState = {};
     this.emit('save', this, numAffected);

From effe6cbafaec7d96456997c11e4d83247e8334c5 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 11:24:13 -0400
Subject: [PATCH 1925/2348] Update model.js

---
 lib/model.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index cceb5598ae1..921de3c2731 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -338,7 +338,6 @@ Model.prototype.$__handleSave = function(options, callback) {
 
     // store the modified paths before the document is reset
     this.$__.modifiedPaths = this.modifiedPaths();
-    // need to prevent this from being called early
     this.$__reset();
 
     _setIsNew(this, false);

From e2528625df87f61a3fd61ec41155c89a1b35923b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 11:25:14 -0400
Subject: [PATCH 1926/2348] removed comments

---
 test/versioning.test.js | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index 75167491ee2..b864ceb0eee 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -548,18 +548,13 @@ describe('versioning', function() {
       yield thing.save();
       assert.equal(thing.__v, 0);
       const thing_1 = yield Thing.findById(thing.id);
-      const thing_2 = yield Thing.findById(thing.id); // this needs to throw an error
+      const thing_2 = yield Thing.findById(thing.id);
       thing_1.set({ price: 2 });
       yield thing_1.save();
       assert.equal(thing_1.__v, 1);
       thing_2.set({ price: 1 });
-      // thing_2.set({ price: 2 });
-      // yield thing_2.save();
       const err = yield thing_2.save().then(() => null, err => err);
       assert.ok(err);
-      // problem is thing_2 is not aware that price has changed and so
-      // when it wants to set it back, thing_2 thinks it is already 1 since
-      // that is what it had when it saved the value originally.
     });
   });
 

From dba8510806fb460ca3ad07ac307b17b6eb6daea1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 12:10:21 -0400
Subject: [PATCH 1927/2348] typescript

---
 index.d.ts                |  4 ++--
 test/typescript/models.ts | 10 ++++++----
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index a0c6bc3e005..8042b3ec06d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -368,7 +368,7 @@ declare module 'mongoose' {
   }
 
   class Document<T = any, TQueryHelpers = {}> {
-    constructor(doc?: any);
+    constructor(doc?: T | any);
 
     /** This documents _id. */
     _id?: T;
@@ -610,7 +610,7 @@ declare module 'mongoose' {
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
   interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
-    new(doc?: any): T;
+    new(doc?: T | any): T;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
     // eslint-disable-next-line @typescript-eslint/ban-types
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 992fe7fc032..49f7d140a23 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -1,4 +1,4 @@
-import { Schema, Document, Model, connection, model, mongoose } from 'mongoose';
+import { Schema, Document, Model, connection, model } from 'mongoose';
 
 function conventionalSyntax(): void {
   interface ITest extends Document {
@@ -71,7 +71,7 @@ function gh10074() {
     age: number;
   }
 
-  type IDogDocument = IDog & Types.Document;
+  type IDogDocument = IDog & Document;
 
   const DogSchema = new Schema<IDogDocument>(
     {
@@ -81,10 +81,12 @@ function gh10074() {
     }
   );
 
-  const Dog = mongoose.model<IDogDocument, Model<IDogDocument>>('dog', DogSchema);
+  const Dog = model<IDogDocument, Model<IDogDocument>>('dog', DogSchema);
 
   const rex = new Dog({
-    // type inference here
+    breed: 'test',
+    name: 'rex',
+    age: '50'
   });
 }
 

From 7f094b149bb683aaee544e9de38eb76febb90871 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 21 Apr 2021 12:48:23 -0400
Subject: [PATCH 1928/2348] fix(connection): avoid db events deprecation
 warning when using `useDb()` with `useUnifiedTopology`

Fix #8267
---
 lib/connection.js                             |  4 ++
 lib/drivers/node-mongodb-native/connection.js | 43 +++++++++++--------
 2 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index a0638f27812..3f69089a58a 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -882,6 +882,7 @@ function _setClient(conn, client, options, dbName) {
   const db = dbName != null ? client.db(dbName) : client.db();
   conn.db = db;
   conn.client = client;
+  conn._closeCalled = client._closeCalled;
 
   const _handleReconnect = () => {
     // If we aren't disconnected, we assume this reconnect is due to a
@@ -1042,6 +1043,9 @@ Connection.prototype._close = function(force, callback) {
   const _this = this;
   const closeCalled = this._closeCalled;
   this._closeCalled = true;
+  if (this.client != null) {
+    this.client._closeCalled = true;
+  }
 
   switch (this.readyState) {
     case STATES.disconnected:
diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index e032eec1960..d2c4fea8c9f 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -128,13 +128,16 @@ NativeConnection.prototype.useDb = function(name, options) {
  */
 
 function listen(conn) {
-  if (conn.db._listening) {
+  if (conn._listening) {
     return;
   }
-  conn.db._listening = true;
+  conn._listening = true;
 
-  conn.db.on('close', function(force) {
-    if (conn._closeCalled) return;
+  conn.client.on('close', function(force) {
+    if (conn._closeCalled) {
+      return;
+    }
+    conn._closeCalled = conn.client._closeCalled;
 
     // the driver never emits an `open` event. auto_reconnect still
     // emits a `close` event but since we never get another
@@ -146,26 +149,30 @@ function listen(conn) {
     }
     conn.onClose(force);
   });
-  conn.db.on('error', function(err) {
+  conn.client.on('error', function(err) {
     conn.emit('error', err);
   });
-  conn.db.on('reconnect', function() {
-    conn.readyState = STATES.connected;
-    conn.emit('reconnect');
-    conn.emit('reconnected');
-    conn.onOpen();
-  });
-  conn.db.on('timeout', function(err) {
-    conn.emit('timeout', err);
-  });
-  conn.db.on('open', function(err, db) {
-    if (STATES.disconnected === conn.readyState && db && db.databaseName) {
+
+  if (!conn.client.s.options.useUnifiedTopology) {
+    conn.db.on('reconnect', function() {
       conn.readyState = STATES.connected;
       conn.emit('reconnect');
       conn.emit('reconnected');
-    }
+      conn.onOpen();
+    });
+    conn.db.on('open', function(err, db) {
+      if (STATES.disconnected === conn.readyState && db && db.databaseName) {
+        conn.readyState = STATES.connected;
+        conn.emit('reconnect');
+        conn.emit('reconnected');
+      }
+    });
+  }
+
+  conn.client.on('timeout', function(err) {
+    conn.emit('timeout', err);
   });
-  conn.db.on('parseError', function(err) {
+  conn.client.on('parseError', function(err) {
     conn.emit('parseError', err);
   });
 }

From 71efabbe9856cab8737929139fba3704c54cdf52 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 15:13:16 -0400
Subject: [PATCH 1929/2348] fix writeConcern problem

---
 lib/drivers/node-mongodb-native/collection.js |  1 -
 lib/helpers/schema/applyWriteConcern.js       |  7 ++++---
 lib/model.js                                  | 20 ++++++++++---------
 lib/query.js                                  |  2 ++
 test/query.test.js                            |  2 +-
 5 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 88eac58dd9b..c8afd294c40 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -214,7 +214,6 @@ function iter(i) {
           'you have `bufferCommands = false`.';
         throw new MongooseError(message);
       }
-
       return collection[i].apply(collection, args);
     } catch (error) {
       // Collection operation may throw because of max bson size, catch it here
diff --git a/lib/helpers/schema/applyWriteConcern.js b/lib/helpers/schema/applyWriteConcern.js
index 168156db117..e7d6a2b1584 100644
--- a/lib/helpers/schema/applyWriteConcern.js
+++ b/lib/helpers/schema/applyWriteConcern.js
@@ -4,13 +4,14 @@ const get = require('../get');
 
 module.exports = function applyWriteConcern(schema, options) {
   const writeConcern = get(schema, 'options.writeConcern', {});
+  options.writeConcern = {};
   if (!('w' in options) && writeConcern.w != null) {
-    options.w = writeConcern.w;
+    options.writeConcern.w = writeConcern.w;
   }
   if (!('j' in options) && writeConcern.j != null) {
-    options.j = writeConcern.j;
+    options.writeConcern.j = writeConcern.j;
   }
   if (!('wtimeout' in options) && writeConcern.wtimeout != null) {
-    options.wtimeout = writeConcern.wtimeout;
+    options.writeConcern.wtimeout = writeConcern.wtimeout;
   }
 };
diff --git a/lib/model.js b/lib/model.js
index b44a436b8d5..bb122234747 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -231,20 +231,22 @@ Model.prototype.$__handleSave = function(options, callback) {
   if ('safe' in options) {
     _handleSafe(options);
   }
+
   applyWriteConcern(this.$__schema, options);
-  if ('w' in options) {
-    saveOptions.w = options.w;
+  if ('w' in options.writeConcern) {
+    saveOptions.w = options.writeConcern.w;
   }
-  if ('j' in options) {
-    saveOptions.j = options.j;
+  if ('j' in options.writeConcern) {
+    saveOptions.j = options.writeConcern.j;
   }
-  if ('wtimeout' in options) {
-    saveOptions.wtimeout = options.wtimeout;
+  if ('wtimeout' in options.writeConcern) {
+    saveOptions.wtimeout = options.writeConcern.wtimeout;
   }
-  if ('checkKeys' in options) {
-    saveOptions.checkKeys = options.checkKeys;
+  if ('checkKeys' in options.writeConcern) {
+    saveOptions.checkKeys = options.writeConcern.checkKeys;
   }
-
+  // goal is to make saveOptions = writeConcern{saveOptions}
+  saveOptions = { writeConcern: saveOptions };
   const session = this.$session();
   if (!saveOptions.hasOwnProperty('session')) {
     saveOptions.session = session;
diff --git a/lib/query.js b/lib/query.js
index e674f0edf6f..818fd9f9357 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -85,6 +85,7 @@ function Query(conditions, options, model, collection) {
     this.schema = model.schema;
   }
 
+
   // this is needed because map reduce returns a model that can be queried, but
   // all of the queries on said model should be lean
   if (this.model && this.model._mapreduce) {
@@ -2841,6 +2842,7 @@ Query.prototype.deleteMany = function(filter, options, callback) {
   }
 
   if (!callback) {
+    // console.log(this.schema.options);
     return Query.base.deleteMany.call(this);
   }
 
diff --git a/test/query.test.js b/test/query.test.js
index e7064b2d7e8..1539dd8473a 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3805,7 +3805,7 @@ describe('Query', function() {
         }
       }
     );
-    const Test = db.model('Test', MySchema);
+    const Test = db.model('Test', MySchema); // pops up on creation of model
     return co(function*() {
       const entry = yield Test.create({ _id: 12345678, op: 'help', size: 54, totalSize: 104 });
       yield entry.save();

From fa6c8f3d8460b9b4c7b3fd02310377996a27a67f Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 15:19:41 -0400
Subject: [PATCH 1930/2348] Update query.js

---
 lib/query.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/query.js b/lib/query.js
index 818fd9f9357..edb08563155 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2842,7 +2842,6 @@ Query.prototype.deleteMany = function(filter, options, callback) {
   }
 
   if (!callback) {
-    // console.log(this.schema.options);
     return Query.base.deleteMany.call(this);
   }
 

From 286661ebeebbd13a0a0c9459e23bd1672f21e3c2 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 15:55:40 -0400
Subject: [PATCH 1931/2348] baby steps

---
 lib/helpers/schema/applyWriteConcern.js | 30 ++++++++++++++++++-------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/lib/helpers/schema/applyWriteConcern.js b/lib/helpers/schema/applyWriteConcern.js
index e7d6a2b1584..e39d93a5d8c 100644
--- a/lib/helpers/schema/applyWriteConcern.js
+++ b/lib/helpers/schema/applyWriteConcern.js
@@ -4,14 +4,28 @@ const get = require('../get');
 
 module.exports = function applyWriteConcern(schema, options) {
   const writeConcern = get(schema, 'options.writeConcern', {});
-  options.writeConcern = {};
-  if (!('w' in options) && writeConcern.w != null) {
-    options.writeConcern.w = writeConcern.w;
-  }
-  if (!('j' in options) && writeConcern.j != null) {
-    options.writeConcern.j = writeConcern.j;
+  if (Object.keys(writeConcern).length != 0) {
+    options.writeConcern = {};
+
+    if (!('w' in options) && writeConcern.w != null) {
+      options.writeConcern.w = writeConcern.w;
+    }
+    if (!('j' in options) && writeConcern.j != null) {
+      options.writeConcern.j = writeConcern.j;
+    }
+    if (!('wtimeout' in options) && writeConcern.wtimeout != null) {
+      options.writeConcern.wtimeout = writeConcern.wtimeout;
+    }
   }
-  if (!('wtimeout' in options) && writeConcern.wtimeout != null) {
-    options.writeConcern.wtimeout = writeConcern.wtimeout;
+  else {
+    if (!('w' in options) && writeConcern.w != null) {
+      options.w = writeConcern.w;
+    }
+    if (!('j' in options) && writeConcern.j != null) {
+      options.j = writeConcern.j;
+    }
+    if (!('wtimeout' in options) && writeConcern.wtimeout != null) {
+      options.wtimeout = writeConcern.wtimeout;
+    }
   }
 };

From 0aa964517d1c9986d8dd6ce86f66740f53390393 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 21 Apr 2021 16:08:13 -0400
Subject: [PATCH 1932/2348] progress

---
 lib/model.js | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index bb122234747..c0adff55cf8 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -233,20 +233,34 @@ Model.prototype.$__handleSave = function(options, callback) {
   }
 
   applyWriteConcern(this.$__schema, options);
-  if ('w' in options.writeConcern) {
-    saveOptions.w = options.writeConcern.w;
-  }
-  if ('j' in options.writeConcern) {
-    saveOptions.j = options.writeConcern.j;
-  }
-  if ('wtimeout' in options.writeConcern) {
-    saveOptions.wtimeout = options.writeConcern.wtimeout;
-  }
-  if ('checkKeys' in options.writeConcern) {
-    saveOptions.checkKeys = options.writeConcern.checkKeys;
+  if (typeof options.writeConcern != 'undefined') {
+    if ('w' in options.writeConcern) {
+      saveOptions.w = options.writeConcern.w;
+    }
+    if ('j' in options.writeConcern) {
+      saveOptions.j = options.writeConcern.j;
+    }
+    if ('wtimeout' in options.writeConcern) {
+      saveOptions.wtimeout = options.writeConcern.wtimeout;
+    }
+    if ('checkKeys' in options.writeConcern) {
+      saveOptions.checkKeys = options.writeConcern.checkKeys;
+    }
+    saveOptions = { writeConcern: saveOptions };
+  } else {
+    if ('w' in options) {
+      saveOptions.w = options.w;
+    }
+    if ('j' in options) {
+      saveOptions.j = options.j;
+    }
+    if ('wtimeout' in options) {
+      saveOptions.wtimeout = options.wtimeout;
+    }
+    if ('checkKeys' in options) {
+      saveOptions.checkKeys = options.checkKeys;
+    }
   }
-  // goal is to make saveOptions = writeConcern{saveOptions}
-  saveOptions = { writeConcern: saveOptions };
   const session = this.$session();
   if (!saveOptions.hasOwnProperty('session')) {
     saveOptions.session = session;

From ea81039d276810cc08a0d74836413920bc3ab6e4 Mon Sep 17 00:00:00 2001
From: Yoonho Go <rhdbsgh0629@naver.com>
Date: Thu, 22 Apr 2021 15:02:24 +0900
Subject: [PATCH 1933/2348] fix(index.d.ts): add parameter type in merge

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 8042b3ec06d..9aace7b67d7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2086,7 +2086,7 @@ declare module 'mongoose' {
     maxTimeMS(ms: number): this;
 
     /** Merges another Query or conditions object into this one. */
-    merge(source: Query<any, any>): this;
+    merge(source: Query<any, any> | FilterQuery<DocType>): this;
 
     /** Specifies a `$mod` condition, filters documents for documents whose `path` property is a number that is equal to `remainder` modulo `divisor`. */
     mod(val: Array<number>): this;

From 7d4c231ff16cc807896d615f46d0cf38509275dc Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 22 Apr 2021 10:16:55 -0400
Subject: [PATCH 1934/2348] made requested changes

---
 lib/model.js | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index c0adff55cf8..6c29bc72247 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -243,10 +243,7 @@ Model.prototype.$__handleSave = function(options, callback) {
     if ('wtimeout' in options.writeConcern) {
       saveOptions.wtimeout = options.writeConcern.wtimeout;
     }
-    if ('checkKeys' in options.writeConcern) {
-      saveOptions.checkKeys = options.writeConcern.checkKeys;
-    }
-    saveOptions = { writeConcern: saveOptions };
+    saveOptions.writeConcern = options.writeConcern;
   } else {
     if ('w' in options) {
       saveOptions.w = options.w;
@@ -257,9 +254,9 @@ Model.prototype.$__handleSave = function(options, callback) {
     if ('wtimeout' in options) {
       saveOptions.wtimeout = options.wtimeout;
     }
-    if ('checkKeys' in options) {
-      saveOptions.checkKeys = options.checkKeys;
-    }
+  }
+  if ('checkKeys' in options) {
+    saveOptions.checkKeys = options.checkKeys;
   }
   const session = this.$session();
   if (!saveOptions.hasOwnProperty('session')) {

From 0a55cbab8afd5137747ea2c628982134232af8c5 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 22 Apr 2021 10:31:47 -0400
Subject: [PATCH 1935/2348] Update versioning.test.js

---
 test/versioning.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index b864ceb0eee..220bb7fe22f 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -554,7 +554,7 @@ describe('versioning', function() {
       assert.equal(thing_1.__v, 1);
       thing_2.set({ price: 1 });
       const err = yield thing_2.save().then(() => null, err => err);
-      assert.ok(err);
+      assert.equal(err.name, 'VersionError');
     });
   });
 

From 04230b2d1b13693f488b7e625f4ccc4cffc9c157 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 22 Apr 2021 11:46:20 -0400
Subject: [PATCH 1936/2348] Update versioning.test.js

---
 test/versioning.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/versioning.test.js b/test/versioning.test.js
index 220bb7fe22f..3380015d167 100644
--- a/test/versioning.test.js
+++ b/test/versioning.test.js
@@ -554,7 +554,7 @@ describe('versioning', function() {
       assert.equal(thing_1.__v, 1);
       thing_2.set({ price: 1 });
       const err = yield thing_2.save().then(() => null, err => err);
-      assert.equal(err.name, 'VersionError');
+      assert.equal(err.name, 'DocumentNotFoundError');
     });
   });
 

From 10e31814deba878a68149486f89fd9b9137c340e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 22 Apr 2021 19:05:27 -0400
Subject: [PATCH 1937/2348] test: adjust writeConcern test

---
 test/query.test.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/test/query.test.js b/test/query.test.js
index 1539dd8473a..f0ae8245318 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -1302,8 +1302,10 @@ describe('Query', function() {
         }
       });
       assert.deepEqual(options, {
-        w: 'majority',
-        j: true
+        writeConcern: {
+          w: 'majority',
+          j: true
+        }
       });
       done();
     });

From 38ab1c9d67e2778ab92989e9922722062898a2c1 Mon Sep 17 00:00:00 2001
From: Abhishek Dubey <ad99526@gmail.com>
Date: Fri, 23 Apr 2021 18:06:08 +0530
Subject: [PATCH 1938/2348] Added a navbar for responsive screen

Added a navbar so that doesn't overlap in devices with screen width less than 1100px
---
 docs/2.7.x/docs/model-definition.html | 194 +++++++++++++++++++++++---
 1 file changed, 171 insertions(+), 23 deletions(-)

diff --git a/docs/2.7.x/docs/model-definition.html b/docs/2.7.x/docs/model-definition.html
index db649835530..17a4ff6c4c7 100644
--- a/docs/2.7.x/docs/model-definition.html
+++ b/docs/2.7.x/docs/model-definition.html
@@ -8,7 +8,147 @@
         padding: 0 30px 30px;
         margin-top: 0;
       }
+      #model-definition-navToggle
+      {
+        display: block;
+        position: relative;
+        top: 50px;
+        left: 50px;
+
+        z-index: 1;
+
+        -webkit-user-select: none;
+        user-select: none;
+      }
+
+      #model-definition-navToggle a
+      {
+        text-decoration: none;
+        color: #232323;
+
+        transition: color 0.3s ease;
+      }
+
+      #model-definition-navToggle a:hover
+      {
+        color: tomato;
+      }
+
+
+      #model-definition-navToggle input
+      {
+        display: block;
+        width: 40px;
+        height: 32px;
+        position: absolute;
+        top: -7px;
+        left: -5px;
+
+        cursor: pointer;
+
+        opacity: 0; /* hide this */
+        z-index: 2; /* and place it over the hamburger */
+
+        -webkit-touch-callout: none;
+      }
+
+      /*
+       * Just a quick hamburger
+       */
+      #model-definition-navToggle span
+      {
+        display: block;
+        width: 33px;
+        height: 4px;
+        margin-bottom: 5px;
+        position: relative;
+
+        background: #cdcdcd;
+        border-radius: 3px;
 
+        z-index: 1;
+
+        transform-origin: 4px 0px;
+
+        transition: transform 0.5s cubic-bezier(0.77,0.2,0.05,1.0),
+                    background 0.5s cubic-bezier(0.77,0.2,0.05,1.0),
+                    opacity 0.55s ease;
+      }
+
+      #model-definition-navToggle span:first-child
+      {
+        transform-origin: 0% 0%;
+      }
+
+      #model-definition-navToggle span:nth-last-child(2)
+      {
+        transform-origin: 0% 100%;
+      }
+
+      /* 
+       * Transform all the slices of hamburger
+       * into a crossmark.
+       */
+      #model-definition-navToggle input:checked ~ span
+      {
+        opacity: 1;
+        transform: rotate(45deg) translate(-2px, -1px);
+        background: #232323;
+      }
+
+      /*
+       * But let's hide the middle one.
+       */
+      #model-definition-navToggle input:checked ~ span:nth-last-child(3)
+      {
+        opacity: 0;
+        transform: rotate(0deg) scale(0.2, 0.2);
+      }
+
+      /*
+       * Ohyeah and the last one should go the other direction
+       */
+      #model-definition-navToggle input:checked ~ span:nth-last-child(2)
+      {
+        transform: rotate(-45deg) translate(0, -1px);
+      }
+
+      /*
+       * Make this absolute positioned
+       * at the top left of the screen
+       */
+      .model-definition-nav
+      {
+        position: absolute;
+        width: 300px;
+        margin: -100px 0 0 -50px;
+        padding: 50px;
+        padding-top: 125px;
+
+        background: #ededed;
+        list-style-type: none;
+        -webkit-font-smoothing: antialiased;
+        /* to stop flickering of text in safari */
+
+        transform-origin: 0% 0%;
+        transform: translate(-100%, 0);
+
+        transition: transform 0.5s cubic-bezier(0.77,0.2,0.05,1.0);
+      }
+
+      .model-definition-nav li
+      {
+        padding: 10px 0;
+        font-size: 22px;
+      }
+
+      /*
+       * And let's slide it in from the left
+       */
+      #model-definition-navToggle input:checked ~ ul
+      {
+        transform: none;
+      }
       #wrap {
         background: url('/docs/2.7.x/images/pattern.png') no-repeat -134px -211px;
         min-height: 600px;
@@ -178,29 +318,37 @@
     <div id="wrap">
       <div id="page">
         <div id="menu">
-          <ul>
-            <li><a href="../index.html">Home</a></li>
-            <li><a href="model-definition.html">Models/Schemas</a></li>
-            <li><a href="schematypes.html">Schema Types</a></li>
-            <li><a href="schema-options.html">Schema Options</a></li>
-            <li><a href="middleware.html">Middleware</a></li>
-            <li><a href="finding-documents.html">Finding Docs</a></li>
-            <li><a href="updating-documents.html">Updating Docs</a></li>
-            <li><a href="query.html">Queries</a></li>
-            <li><a href="querystream.html">Query Streams</a></li>
-            <li><a href="methods-statics.html">Methods &amp; Statics</a>
-            <li><a href="defaults.html">Defaults</a></li>
-            <li><a href="indexes.html">Indexes</a></li>
-            <li><a href="validation.html">Validation</a></li>
-            <li><a href="virtuals.html">Virtuals</a></li>
-            <li><a href="getters-setters.html">Getters / Setters</a></li>
-            <li><a href="embedded-documents.html">Embedded Docs</a></li>
-            <li><a href="populate.html">Populate (DBRef-like)</a></li>
-            <li><a href="plugins.html">Plugins</a></li>
-            <li><a href="errors.html">Errors</a></li>
-            <li><a href="migration-1x-2x.html">v1x - v2x Migration</a></li>
-            <li><a href="api.html">API</a></li>
-          </ul>
+          <nav role="navigation">
+            <div id="model-definition-navToggle">
+              <input type="checkbox" />
+              <span></span>
+              <span></span>
+              <span></span>
+              <ul class='model-definition-nav'>
+                <li><a href="../index.html">Home</a></li>
+                <li><a href="model-definition.html">Models/Schemas</a></li>
+                <li><a href="schematypes.html">Schema Types</a></li>
+                <li><a href="schema-options.html">Schema Options</a></li>
+                <li><a href="middleware.html">Middleware</a></li>
+                <li><a href="finding-documents.html">Finding Docs</a></li>
+                <li><a href="updating-documents.html">Updating Docs</a></li>
+                <li><a href="query.html">Queries</a></li>
+                <li><a href="querystream.html">Query Streams</a></li>
+                <li><a href="methods-statics.html">Methods &amp; Statics</a>
+                <li><a href="defaults.html">Defaults</a></li>
+                <li><a href="indexes.html">Indexes</a></li>
+                <li><a href="validation.html">Validation</a></li>
+                <li><a href="virtuals.html">Virtuals</a></li>
+                <li><a href="getters-setters.html">Getters / Setters</a></li>
+                <li><a href="embedded-documents.html">Embedded Docs</a></li>
+                <li><a href="populate.html">Populate (DBRef-like)</a></li>
+                <li><a href="plugins.html">Plugins</a></li>
+                <li><a href="errors.html">Errors</a></li>
+                <li><a href="migration-1x-2x.html">v1x - v2x Migration</a></li>
+                <li><a href="api.html">API</a></li>
+              </ul>
+            </div>
+          </nav>
         </div>
 
         <h1><a href="../index.html">Mongoose</a></h1>

From a773e780f8ce14ff3cc31cf2e40f0d8c4898ff56 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 23 Apr 2021 13:35:58 -0400
Subject: [PATCH 1939/2348] fix failing test

---
 lib/helpers/schema/applyWriteConcern.js |  1 -
 lib/model.js                            |  4 +--
 lib/query.js                            | 37 +++++++++++++++++++++----
 3 files changed, 34 insertions(+), 8 deletions(-)

diff --git a/lib/helpers/schema/applyWriteConcern.js b/lib/helpers/schema/applyWriteConcern.js
index e39d93a5d8c..4095bd94bc7 100644
--- a/lib/helpers/schema/applyWriteConcern.js
+++ b/lib/helpers/schema/applyWriteConcern.js
@@ -6,7 +6,6 @@ module.exports = function applyWriteConcern(schema, options) {
   const writeConcern = get(schema, 'options.writeConcern', {});
   if (Object.keys(writeConcern).length != 0) {
     options.writeConcern = {};
-
     if (!('w' in options) && writeConcern.w != null) {
       options.writeConcern.w = writeConcern.w;
     }
diff --git a/lib/model.js b/lib/model.js
index 6c29bc72247..bc7e82bbef6 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -233,6 +233,7 @@ Model.prototype.$__handleSave = function(options, callback) {
   }
 
   applyWriteConcern(this.$__schema, options);
+
   if (typeof options.writeConcern != 'undefined') {
     if ('w' in options.writeConcern) {
       saveOptions.w = options.writeConcern.w;
@@ -243,7 +244,7 @@ Model.prototype.$__handleSave = function(options, callback) {
     if ('wtimeout' in options.writeConcern) {
       saveOptions.wtimeout = options.writeConcern.wtimeout;
     }
-    saveOptions.writeConcern = options.writeConcern;
+    saveOptions = { writeConcern: saveOptions };
   } else {
     if ('w' in options) {
       saveOptions.w = options.w;
@@ -266,7 +267,6 @@ Model.prototype.$__handleSave = function(options, callback) {
   if (Object.keys(saveOptions).length === 0) {
     saveOptions = null;
   }
-
   if (this.isNew) {
     // send entire doc
     const obj = this.toObject(saveToObjectOptions);
diff --git a/lib/query.js b/lib/query.js
index edb08563155..da79df81788 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1169,7 +1169,12 @@ Query.prototype.w = function w(val) {
   if (val == null) {
     delete this.options.w;
   }
-  this.options.w = val;
+  if (this.options.writeConcern != null) {
+    this.options.writeConcern.w = val;
+  }
+  else {
+    this.options.w = val;
+  }
   return this;
 };
 
@@ -1207,7 +1212,12 @@ Query.prototype.j = function j(val) {
   if (val == null) {
     delete this.options.j;
   }
-  this.options.j = val;
+  if (this.options.writeConcern != null) {
+    this.options.writeConcern.j = val;
+  }
+  else {
+    this.options.j = val;
+  }
   return this;
 };
 
@@ -1253,7 +1263,12 @@ Query.prototype.wtimeout = function wtimeout(ms) {
   if (ms == null) {
     delete this.options.wtimeout;
   }
-  this.options.wtimeout = ms;
+  if (this.options.writeConcern != null) {
+    this.options.writeConcern.wtimeout = ms;
+  }
+  else {
+    this.options.wtimeout = ms;
+  }
   return this;
 };
 
@@ -1661,7 +1676,6 @@ Query.prototype._updateForExec = function() {
 
 Query.prototype._optionsForExec = function(model) {
   const options = utils.clone(this.options);
-
   delete options.populate;
   model = model || this.model;
 
@@ -1685,7 +1699,20 @@ Query.prototype._optionsForExec = function(model) {
   if (options.upsert !== void 0) {
     options.upsert = !!options.upsert;
   }
-
+  if (options.writeConcern) {
+    if (options.j) {
+      options.writeConcern.j = options.j;
+      delete options.j;
+    }
+    if (options.w) {
+      options.writeConcern.w = options.w;
+      delete options.w;
+    }
+    if (options.wtimeout) {
+      options.writeConcern.wtimeout = options.wtimeout;
+      delete options.wtimeout;
+    }
+  }
   return options;
 };
 

From 87b17071651b5aea8f6071826e2ba31b9e371236 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Apr 2021 14:13:00 -0400
Subject: [PATCH 1940/2348] fix: upgrade to sift@13.5.2 to work around
 transitive dev dependency security warning

Fix #10121
---
 lib/helpers/populate/assignVals.js |  4 ++--
 package.json                       | 38 ++++++++++++++++--------------
 2 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 0e556b33536..33c618dc37c 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -84,8 +84,8 @@ module.exports = function assignVals(o) {
       valueToSet = numDocs(rawIds[i]);
     } else if (Array.isArray(o.match)) {
       valueToSet = Array.isArray(rawIds[i]) ?
-        sift(o.match[i], rawIds[i]) :
-        sift(o.match[i], [rawIds[i]])[0];
+        rawIds[i].filter(sift(o.match[i])) :
+        [rawIds[i]].filter(sift(o.match[i]))[0];
     } else {
       valueToSet = rawIds[i];
     }
diff --git a/package.json b/package.json
index bc444a018c1..673f6be0d44 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
     "ms": "2.1.2",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.2.1",
-    "sift": "7.0.1",
+    "sift": "13.5.2",
     "sliced": "1.0.1"
   },
   "devDependencies": {
@@ -107,23 +107,25 @@
     "extends": [
       "eslint:recommended"
     ],
-    "overrides": [{
-      "files": [
-        "**/*.{ts,tsx}"
-      ],
-      "extends": [
-        "plugin:@typescript-eslint/eslint-recommended",
-        "plugin:@typescript-eslint/recommended"
-      ],
-      "plugins": [
-        "@typescript-eslint"
-      ],
-      "rules": {
-        "@typescript-eslint/no-explicit-any": "off",
-        "@typescript-eslint/ban-types": "off",
-        "@typescript-eslint/no-unused-vars": "off"
+    "overrides": [
+      {
+        "files": [
+          "**/*.{ts,tsx}"
+        ],
+        "extends": [
+          "plugin:@typescript-eslint/eslint-recommended",
+          "plugin:@typescript-eslint/recommended"
+        ],
+        "plugins": [
+          "@typescript-eslint"
+        ],
+        "rules": {
+          "@typescript-eslint/no-explicit-any": "off",
+          "@typescript-eslint/ban-types": "off",
+          "@typescript-eslint/no-unused-vars": "off"
+        }
       }
-    }],
+    ],
     "plugins": [
       "mocha-no-only"
     ],
@@ -247,4 +249,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
\ No newline at end of file
+}

From 9ca6c063a1c41719f4b9475b1c6c4b086e0d5716 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 23 Apr 2021 14:30:57 -0400
Subject: [PATCH 1941/2348] made requested changes

---
 lib/model.js | 2 +-
 lib/query.js | 9 +++------
 2 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index bc7e82bbef6..96fb81bf092 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -244,7 +244,7 @@ Model.prototype.$__handleSave = function(options, callback) {
     if ('wtimeout' in options.writeConcern) {
       saveOptions.wtimeout = options.writeConcern.wtimeout;
     }
-    saveOptions = { writeConcern: saveOptions };
+    saveOptions.writeConcern = Object.assign({}, options.writeConcern);
   } else {
     if ('w' in options) {
       saveOptions.w = options.w;
diff --git a/lib/query.js b/lib/query.js
index da79df81788..8f5eb403715 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1171,8 +1171,7 @@ Query.prototype.w = function w(val) {
   }
   if (this.options.writeConcern != null) {
     this.options.writeConcern.w = val;
-  }
-  else {
+  } else {
     this.options.w = val;
   }
   return this;
@@ -1214,8 +1213,7 @@ Query.prototype.j = function j(val) {
   }
   if (this.options.writeConcern != null) {
     this.options.writeConcern.j = val;
-  }
-  else {
+  } else {
     this.options.j = val;
   }
   return this;
@@ -1265,8 +1263,7 @@ Query.prototype.wtimeout = function wtimeout(ms) {
   }
   if (this.options.writeConcern != null) {
     this.options.writeConcern.wtimeout = ms;
-  }
-  else {
+  } else {
     this.options.wtimeout = ms;
   }
   return this;

From 9a34bf459962cad985966c1720511062ffd5584d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 23 Apr 2021 15:01:44 -0400
Subject: [PATCH 1942/2348] fix the writeConcern issue

---
 lib/model.js | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 96fb81bf092..f31d20602ca 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -233,18 +233,17 @@ Model.prototype.$__handleSave = function(options, callback) {
   }
 
   applyWriteConcern(this.$__schema, options);
-
   if (typeof options.writeConcern != 'undefined') {
+    saveOptions.writeConcern = {};
     if ('w' in options.writeConcern) {
-      saveOptions.w = options.writeConcern.w;
+      saveOptions.writeConcern.w = options.writeConcern.w;
     }
     if ('j' in options.writeConcern) {
-      saveOptions.j = options.writeConcern.j;
+      saveOptions.writeConcern.j = options.writeConcern.j;
     }
     if ('wtimeout' in options.writeConcern) {
-      saveOptions.wtimeout = options.writeConcern.wtimeout;
+      saveOptions.writeConcern.wtimeout = options.writeConcern.wtimeout;
     }
-    saveOptions.writeConcern = Object.assign({}, options.writeConcern);
   } else {
     if ('w' in options) {
       saveOptions.w = options.w;

From f96f70255eda0c4af8c2a32a0687e01373fb67c1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Apr 2021 17:29:57 -0400
Subject: [PATCH 1943/2348] fix(model): use `obj` as `context` in
 `Model.validate()` if `obj` is a document

Fix #10132
---
 lib/model.js       |  6 ++++++
 test/model.test.js | 20 ++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index 921de3c2731..17436e6c0f3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4028,6 +4028,12 @@ Model.aggregate = function aggregate(pipeline, callback) {
  */
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
+  if (context === void 0 && obj instanceof Model) {
+    // For convenience, if we're validating a document, make `context` default to
+    // the model so users don't have to always pass `context`, re: gh-10132.
+    context = obj;
+  }
+
   return this.db.base._promiseOrCallback(callback, cb => {
     const schema = this.schema;
     let paths = Object.keys(schema.paths);
diff --git a/test/model.test.js b/test/model.test.js
index 06fe7c49031..bde6cf2de16 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6735,6 +6735,26 @@ describe('Model', function() {
     });
   });
 
+  it('Model.validate(...) uses document instance as context by default (gh-10132)', function() {
+    const userSchema = new Schema({
+      name: {
+        type: String,
+        required: function() {
+          return this.nameRequired;
+        }
+      },
+      nameRequired: Boolean
+    });
+
+    const User = db.model('User', userSchema);
+    return co(function*() {
+      const user = new User({ name: 'test', nameRequired: false });
+      const err = yield User.validate(user).catch(err => err);
+
+      assert.ifError(err);
+    });
+  });
+
   it('sets correct `Document#op` with `save()` (gh-8439)', function() {
     const schema = Schema({ name: String });
     const ops = [];

From bf85ae6ac66e5f5033fd511f2e65bcae38dbb397 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Apr 2021 17:35:09 -0400
Subject: [PATCH 1944/2348] chore: update opencollective sponsors

---
 index.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.pug b/index.pug
index 8bfe2c76f71..b5d101ced5a 100644
--- a/index.pug
+++ b/index.pug
@@ -349,6 +349,12 @@ html(lang='en')
               <a rel="sponsored" href="https://casinomartini.com/nz/new-online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casino-martini/8efce1c/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://ufa96bet.com/">
+                <img class="sponsor" src="https://images.opencollective.com/nathan-oscar898/257fa8f/avatar/256.png" style="height: 100px">
+              </a>
+              <a rel="sponsored" href="https://slot-xo888.com/">
+                <img class="sponsor" src="https://images.opencollective.com/siwagorn/694a96c/avatar/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 1ba4b56d095b0e6fc177738463a91eb90b647c68 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 23 Apr 2021 17:37:59 -0400
Subject: [PATCH 1945/2348] chore: fix docs build

---
 docs/search.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/search.js b/docs/search.js
index c85a0feaf55..e22a460df39 100644
--- a/docs/search.js
+++ b/docs/search.js
@@ -50,7 +50,7 @@ for (const filename of files) {
   } else if (file.guide) {
     let text = fs.readFileSync(filename, 'utf8');
     text = text.substr(text.indexOf('block content') + 'block content\n'.length);
-    text = pug.render(`div\n${text}`, { filters: { markdown } });
+    text = pug.render(`div\n${text}`, { filters: { markdown }, filename });
 
     const content = new Content({
       title: file.title,

From 1eefd9e9af6f1c4bccd40815f70bd95aa0153320 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Apr 2021 13:50:20 -0400
Subject: [PATCH 1946/2348] fix(index.d.ts): clarify that `eachAsync()`
 callback receives a single doc rather than array of docs unless `batchSize`
 is set

Fix #10135
---
 index.d.ts                      |  6 ++++--
 lib/helpers/cursor/eachAsync.js | 28 ++++++++++++++++++++--------
 test/typescript/queries.ts      |  6 ++++++
 3 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 9aace7b67d7..a2640d34948 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2379,8 +2379,10 @@ declare module 'mongoose' {
      * will wait for the promise to resolve before iterating on to the next one.
      * Returns a promise that resolves when done.
      */
-    eachAsync(fn: (doc: DocType| [DocType]) => any, options?: { parallel?: number, batchSize?: number }): Promise<void>;
-    eachAsync(fn: (doc: DocType| [DocType]) => any, options?: { parallel?: number, batchSize?: number }, cb?: (err: CallbackError) => void): void;
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }): Promise<void>;
+    eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }): Promise<void>;
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number, batchSize?: number }, cb?: (err: CallbackError) => void): void;
+    eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }, cb?: (err: CallbackError) => void): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index 96e9c933a75..ab4a8a41d4d 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -26,6 +26,18 @@ module.exports = function eachAsync(next, fn, options, callback) {
   const enqueue = asyncQueue();
 
   return promiseOrCallback(callback, cb => {
+    if (batchSize != null) {
+      if (typeof batchSize !== 'number') {
+        throw new TypeError('batchSize must be a number');
+      }
+      if (batchSize < 1) {
+        throw new TypeError('batchSize must be at least 1');
+      }
+      if (batchSize !== Math.floor(batchSize)) {
+        throw new TypeError('batchSize must be a positive integer');
+      }
+    }
+
     iterate(cb);
   });
 
@@ -58,9 +70,9 @@ module.exports = function eachAsync(next, fn, options, callback) {
           drained = true;
           if (handleResultsInProgress <= 0) {
             finalCallback(null);
-          }
-          else if (batchSize && documentsBatch.length)
+          } else if (batchSize != null && documentsBatch.length) {
             handleNextResult(documentsBatch, currentDocumentIndex++, handleNextResultCallBack);
+          }
           return done();
         }
 
@@ -70,25 +82,25 @@ module.exports = function eachAsync(next, fn, options, callback) {
         // make sure we know that we still have a result to handle re: #8422
         process.nextTick(() => done());
 
-        if (batchSize) {
+        if (batchSize != null) {
           documentsBatch.push(doc);
         }
 
         // If the current documents size is less than the provided patch size don't process the documents yet
-        if (batchSize && documentsBatch.length !== batchSize) {
+        if (batchSize != null && documentsBatch.length !== batchSize) {
           setTimeout(() => enqueue(fetch), 0);
           return;
         }
 
-        const docsToProcess = batchSize ? documentsBatch : doc;
+        const docsToProcess = batchSize != null ? documentsBatch : doc;
 
         function handleNextResultCallBack(err) {
-          if (batchSize) {
+          if (batchSize != null) {
             handleResultsInProgress -= documentsBatch.length;
             documentsBatch = [];
-          }
-          else
+          } else {
             --handleResultsInProgress;
+          }
           if (err != null) {
             error = err;
             return finalCallback(err);
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index ffb54e6ad3e..fcd1de717de 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -100,4 +100,10 @@ function testGenericQuery(): void {
   async function findSomething<T>(model: Model<CommonInterface<T>>): Promise<CommonInterface<T>> {
     return model.findOne({ something: 'test' }).orFail().exec();
   }
+}
+
+function eachAsync(): void {
+  Test.find().cursor().eachAsync((doc: ITest) => console.log(doc.name));
+
+  Test.find().cursor().eachAsync((docs: ITest[]) => console.log(docs[0].name), { batchSize: 2 });
 }
\ No newline at end of file

From 46ba888aa5fc8fd6ab05ec74182ad4c62622feb7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Apr 2021 17:14:54 -0400
Subject: [PATCH 1947/2348] test(populate): repro part of #10117

---
 test/model.populate.test.js | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 289f88f8b18..d3a708e9bab 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -5049,7 +5049,7 @@ describe('model: populate:', function() {
         });
       });
 
-      it('with no results (gh-4284)', function(done) {
+      it('with no results XYZ (gh-4284)', function(done) {
         const PersonSchema = new Schema({
           name: String,
           authored: [Number]
@@ -10296,4 +10296,26 @@ describe('model: populate:', function() {
       assert.equal(populatedBooks[1].author.name, 'Author1');
     });
   });
+
+  it('handles virtual populate when foreignField is an array with duplicates (gh-10117)', function() {
+    const bookSchema = new Schema({ name: String, author: String });
+    bookSchema.virtual('authors', {
+      ref: 'Person',
+      localField: 'author',
+      foreignField: 'aliases',
+      justOne: false
+    });
+    const Book = db.model('Book', bookSchema);
+    const Author = db.model('Person', new Schema({ aliases: [String] }));
+
+    return co(function*() {
+      yield Author.create({ aliases: ['author1', 'author2', 'author1'] });
+
+      const book = yield Book.create({ name: 'Book1', author: 'author1' });
+
+      const fromDb = yield Book.findById(book).populate('authors');
+      assert.equal(fromDb.authors.length, 1);
+      assert.deepEqual(fromDb.toObject({ virtuals: true }).authors[0].aliases, ['author1', 'author2', 'author1']);
+    });
+  });
 });

From 0aab1259636aa219a5533b06e541e0090461933c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Apr 2021 17:15:42 -0400
Subject: [PATCH 1948/2348] fix(populate): dedupe when virtual populate
 foreignField is an array to avoid duplicate docs in result

Re: #10117
---
 lib/model.js |  4 +++-
 lib/utils.js | 12 ++++++------
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 17436e6c0f3..ccb9a1d049f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4542,6 +4542,7 @@ function _execPopulateQuery(mod, match, select, assignmentOpts, callback) {
     if (err != null) {
       return callback(err);
     }
+
     for (const val of docs) {
       leanPopulateMap.set(val, mod.model);
     }
@@ -4575,10 +4576,11 @@ function _assign(model, vals, mod, assignmentOpts) {
     if (val == null) {
       continue;
     }
+
     for (const foreignField of mod.foreignField) {
       _val = utils.getValue(foreignField, val);
       if (Array.isArray(_val)) {
-        _val = utils.array.flatten(_val);
+        _val = utils.array.unique(utils.array.flatten(_val));
 
         for (let __val of _val) {
           if (__val instanceof Document) {
diff --git a/lib/utils.js b/lib/utils.js
index 59ef7e04985..7966c332a3b 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -755,23 +755,23 @@ exports.isArrayIndex = function(val) {
  */
 
 exports.array.unique = function(arr) {
-  const primitives = {};
-  const ids = {};
+  const primitives = new Set();
+  const ids = new Set();
   const ret = [];
 
   for (const item of arr) {
     if (typeof item === 'number' || typeof item === 'string' || item == null) {
-      if (primitives[item]) {
+      if (primitives.has(item)) {
         continue;
       }
       ret.push(item);
-      primitives[item] = true;
+      primitives.add(item);
     } else if (item instanceof ObjectId) {
-      if (ids[item.toString()]) {
+      if (ids.has(item.toString())) {
         continue;
       }
       ret.push(item);
-      ids[item.toString()] = true;
+      ids.add(item.toString());
     } else {
       ret.push(item);
     }

From 124d8ef31db9307eeb3faaacf91b5a913f78e57d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 24 Apr 2021 18:18:39 -0400
Subject: [PATCH 1949/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index b5d101ced5a..1d0dd785a47 100644
--- a/index.pug
+++ b/index.pug
@@ -355,6 +355,9 @@ html(lang='en')
               <a rel="sponsored" href="https://slot-xo888.com/">
                 <img class="sponsor" src="https://images.opencollective.com/siwagorn/694a96c/avatar/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://www.slotbar888.com/">
+                <img class="sponsor" src="https://images.opencollective.com/nathan-oscar989/2843cec/avatar/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From e00a2bae6a7d5c2e4d7e8d8b5db36be4e62ddc3a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 25 Apr 2021 13:32:20 -0400
Subject: [PATCH 1950/2348] test(populate): repro #10117

---
 test/model.populate.test.js | 40 +++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index d3a708e9bab..7487f61347c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10318,4 +10318,44 @@ describe('model: populate:', function() {
       assert.deepEqual(fromDb.toObject({ virtuals: true }).authors[0].aliases, ['author1', 'author2', 'author1']);
     });
   });
+
+  it('handles virtual populate with `$elemMatch` in custom match when `foreignField` is an array (gh-10117)', function() {
+    const User = db.model('User', mongoose.Schema({
+      name: String,
+      access: [{ role: String, deletedAt: Date, organization: 'ObjectId' }]
+    }));
+
+    const organizationSchema = mongoose.Schema({ name: String });
+    organizationSchema.virtual('administrators', {
+      ref: 'User',
+      localField: '_id',
+      foreignField: 'access.organization'
+    });
+    const Organization = db.model('Organization', organizationSchema);
+
+    return co(function*() {
+      const org = yield Organization.create({ name: 'test org' });
+      yield User.create([
+        { name: 'user1', access: [{ role: 'admin', organization: org._id }] },
+        { name: 'user2', access: [{ role: 'admin', organization: null }] },
+        {
+          name: 'user3',
+          access: [
+            { role: 'admin', organization: org._id, deletedAt: new Date() },
+            { role: 'admin', organization: null }
+          ]
+        }
+      ]);
+
+      const res = yield Organization.findById(org).populate({
+        path: 'administrators',
+        match: {
+          access: { $elemMatch: { role: 'admin', deletedAt: { $exists: false } } }
+        }
+      });
+      assert.equal(res.administrators.length, 1);
+      assert.equal(res.administrators[0].name, 'user1');
+
+    });
+  });
 });

From 53582a6fb7832409dd57b61336a28aee994541f9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 25 Apr 2021 13:34:08 -0400
Subject: [PATCH 1951/2348] fix(populate): add `localField` filter to
 `$elemMatch` on virtual populate when custom `match` has a `$elemMatch` and
 `foreignField` is an array

Fix #10117
---
 lib/helpers/path/parentPaths.js | 13 +++++++++++++
 lib/model.js                    | 11 +++++++++++
 test/model.populate.test.js     |  3 +++
 3 files changed, 27 insertions(+)
 create mode 100644 lib/helpers/path/parentPaths.js

diff --git a/lib/helpers/path/parentPaths.js b/lib/helpers/path/parentPaths.js
new file mode 100644
index 00000000000..77d00ae89bb
--- /dev/null
+++ b/lib/helpers/path/parentPaths.js
@@ -0,0 +1,13 @@
+'use strict';
+
+module.exports = function parentPaths(path) {
+  const pieces = path.split('.');
+  let cur = '';
+  const ret = [];
+  for (let i = 0; i < pieces.length; ++i) {
+    cur += (cur.length > 0 ? '.' : '') + pieces[i];
+    ret.push(cur);
+  }
+
+  return ret;
+};
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index ccb9a1d049f..7bf3a92e285 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -45,6 +45,7 @@ const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedIncl
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
 const modifiedPaths = require('./helpers/update/modifiedPaths');
 const parallelLimit = require('./helpers/parallelLimit');
+const parentPaths = require('./helpers/path/parentPaths');
 const removeDeselectedForeignField = require('./helpers/populate/removeDeselectedForeignField');
 const util = require('util');
 const utils = require('./utils');
@@ -4411,6 +4412,16 @@ function populate(model, docs, options, callback) {
         ids = _filterInvalidIds(ids, foreignSchemaType, mod.options.skipInvalidIds);
         match[foreignField] = { $in: ids };
       }
+
+      const _parentPaths = parentPaths(foreignField);
+      for (let i = 0; i < _parentPaths.length - 1; ++i) {
+        const cur = _parentPaths[i];
+        if (match[cur] != null && match[cur].$elemMatch != null) {
+          match[cur].$elemMatch[foreignField.slice(cur.length + 1)] = { $in: ids };
+          delete match[foreignField];
+          break;
+        }
+      }
     } else {
       const $or = [];
       if (Array.isArray(match.$or)) {
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 7487f61347c..a2e9bbe8dbf 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10341,6 +10341,9 @@ describe('model: populate:', function() {
         {
           name: 'user3',
           access: [
+            // Shouldn't end up in result because first entry matches on `_id` but
+            // not custom `$elemMatch`, and 2nd entry matches on custom `$elemMatch`
+            // but not on `_id`.
             { role: 'admin', organization: org._id, deletedAt: new Date() },
             { role: 'admin', organization: null }
           ]

From de0cdc40be1341eda108dcfa113a1ff1dd631668 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 25 Apr 2021 14:38:53 -0400
Subject: [PATCH 1952/2348] refactor(populate): move logic that creates
 populate query filter into helper

Re: #10117
---
 .../populate/createPopulateQueryFilter.js     | 79 +++++++++++++++++++
 lib/model.js                                  | 73 +----------------
 2 files changed, 81 insertions(+), 71 deletions(-)
 create mode 100644 lib/helpers/populate/createPopulateQueryFilter.js

diff --git a/lib/helpers/populate/createPopulateQueryFilter.js b/lib/helpers/populate/createPopulateQueryFilter.js
new file mode 100644
index 00000000000..db7f9c69da7
--- /dev/null
+++ b/lib/helpers/populate/createPopulateQueryFilter.js
@@ -0,0 +1,79 @@
+'use strict';
+
+const SkipPopulateValue = require('./SkipPopulateValue');
+const parentPaths = require('../path/parentPaths');
+
+module.exports = function createPopulateQueryFilter(ids, _match, _foreignField, model, skipInvalidIds) {
+  const match = _formatMatch(_match);
+
+  if (_foreignField.size === 1) {
+    const foreignField = Array.from(_foreignField)[0];
+    const foreignSchemaType = model.schema.path(foreignField);
+    if (foreignField !== '_id' || !match['_id']) {
+      ids = _filterInvalidIds(ids, foreignSchemaType, skipInvalidIds);
+      match[foreignField] = { $in: ids };
+    }
+
+    const _parentPaths = parentPaths(foreignField);
+    for (let i = 0; i < _parentPaths.length - 1; ++i) {
+      const cur = _parentPaths[i];
+      if (match[cur] != null && match[cur].$elemMatch != null) {
+        match[cur].$elemMatch[foreignField.slice(cur.length + 1)] = { $in: ids };
+        delete match[foreignField];
+        break;
+      }
+    }
+  } else {
+    const $or = [];
+    if (Array.isArray(match.$or)) {
+      match.$and = [{ $or: match.$or }, { $or: $or }];
+      delete match.$or;
+    } else {
+      match.$or = $or;
+    }
+    for (const foreignField of _foreignField) {
+      if (foreignField !== '_id' || !match['_id']) {
+        const foreignSchemaType = model.schema.path(foreignField);
+        ids = _filterInvalidIds(ids, foreignSchemaType, skipInvalidIds);
+        $or.push({ [foreignField]: { $in: ids } });
+      }
+    }
+  }
+
+  return match;
+};
+
+/*!
+ * Optionally filter out invalid ids that don't conform to foreign field's schema
+ * to avoid cast errors (gh-7706)
+ */
+
+function _filterInvalidIds(ids, foreignSchemaType, skipInvalidIds) {
+  ids = ids.filter(v => !(v instanceof SkipPopulateValue));
+  if (!skipInvalidIds) {
+    return ids;
+  }
+  return ids.filter(id => {
+    try {
+      foreignSchemaType.cast(id);
+      return true;
+    } catch (err) {
+      return false;
+    }
+  });
+}
+
+/*!
+ * Format `mod.match` given that it may be an array that we need to $or if
+ * the client has multiple docs with match functions
+ */
+
+function _formatMatch(match) {
+  if (Array.isArray(match)) {
+    if (match.length > 1) {
+      return { $or: [].concat(match.map(m => Object.assign({}, m))) };
+    }
+    return Object.assign({}, match[0]);
+  }
+  return Object.assign({}, match);
+}
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index 7bf3a92e285..d9c94853ec2 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -19,7 +19,6 @@ const RemoveOptions = require('./options/removeOptions');
 const SaveOptions = require('./options/saveOptions');
 const Schema = require('./schema');
 const ServerSelectionError = require('./error/serverSelection');
-const SkipPopulateValue = require('./helpers/populate/SkipPopulateValue');
 const ValidationError = require('./error/validation');
 const VersionError = require('./error/version');
 const ParallelSaveError = require('./error/parallelSave');
@@ -31,6 +30,7 @@ const applyStatics = require('./helpers/model/applyStatics');
 const applyWriteConcern = require('./helpers/schema/applyWriteConcern');
 const assignVals = require('./helpers/populate/assignVals');
 const castBulkWrite = require('./helpers/model/castBulkWrite');
+const createPopulateQueryFilter = require('./helpers/populate/createPopulateQueryFilter');
 const getDefaultBulkwriteResult = require('./helpers/getDefaultBulkwriteResult');
 const discriminator = require('./helpers/model/discriminator');
 const each = require('./helpers/each');
@@ -45,7 +45,6 @@ const isPathSelectedInclusive = require('./helpers/projection/isPathSelectedIncl
 const leanPopulateMap = require('./helpers/populate/leanPopulateMap');
 const modifiedPaths = require('./helpers/update/modifiedPaths');
 const parallelLimit = require('./helpers/parallelLimit');
-const parentPaths = require('./helpers/path/parentPaths');
 const removeDeselectedForeignField = require('./helpers/populate/removeDeselectedForeignField');
 const util = require('util');
 const utils = require('./utils');
@@ -4385,7 +4384,6 @@ function populate(model, docs, options, callback) {
   for (let i = 0; i < len; ++i) {
     const mod = modelsMap[i];
     let select = mod.options.select;
-    const match = _formatMatch(mod.match);
     let ids = utils.array.flatten(mod.ids, flatten);
     ids = utils.array.unique(ids);
 
@@ -4405,39 +4403,7 @@ function populate(model, docs, options, callback) {
     }
 
     hasOne = true;
-    if (mod.foreignField.size === 1) {
-      const foreignField = Array.from(mod.foreignField)[0];
-      const foreignSchemaType = mod.model.schema.path(foreignField);
-      if (foreignField !== '_id' || !match['_id']) {
-        ids = _filterInvalidIds(ids, foreignSchemaType, mod.options.skipInvalidIds);
-        match[foreignField] = { $in: ids };
-      }
-
-      const _parentPaths = parentPaths(foreignField);
-      for (let i = 0; i < _parentPaths.length - 1; ++i) {
-        const cur = _parentPaths[i];
-        if (match[cur] != null && match[cur].$elemMatch != null) {
-          match[cur].$elemMatch[foreignField.slice(cur.length + 1)] = { $in: ids };
-          delete match[foreignField];
-          break;
-        }
-      }
-    } else {
-      const $or = [];
-      if (Array.isArray(match.$or)) {
-        match.$and = [{ $or: match.$or }, { $or: $or }];
-        delete match.$or;
-      } else {
-        match.$or = $or;
-      }
-      for (const foreignField of mod.foreignField) {
-        if (foreignField !== '_id' || !match['_id']) {
-          const foreignSchemaType = mod.model.schema.path(foreignField);
-          ids = _filterInvalidIds(ids, foreignSchemaType, mod.options.skipInvalidIds);
-          $or.push({ [foreignField]: { $in: ids } });
-        }
-      }
-    }
+    const match = createPopulateQueryFilter(ids, mod.match, mod.foreignField, mod.model, mod.options.skipInvalidIds);
 
     if (assignmentOpts.excludeId) {
       // override the exclusion from the query so we can use the _id
@@ -4668,41 +4634,6 @@ function _assign(model, vals, mod, assignmentOpts) {
   });
 }
 
-/*!
- * Optionally filter out invalid ids that don't conform to foreign field's schema
- * to avoid cast errors (gh-7706)
- */
-
-function _filterInvalidIds(ids, foreignSchemaType, skipInvalidIds) {
-  ids = ids.filter(v => !(v instanceof SkipPopulateValue));
-  if (!skipInvalidIds) {
-    return ids;
-  }
-  return ids.filter(id => {
-    try {
-      foreignSchemaType.cast(id);
-      return true;
-    } catch (err) {
-      return false;
-    }
-  });
-}
-
-/*!
- * Format `mod.match` given that it may be an array that we need to $or if
- * the client has multiple docs with match functions
- */
-
-function _formatMatch(match) {
-  if (Array.isArray(match)) {
-    if (match.length > 1) {
-      return { $or: [].concat(match.map(m => Object.assign({}, m))) };
-    }
-    return Object.assign({}, match[0]);
-  }
-  return Object.assign({}, match);
-}
-
 /*!
  * Compiler utility.
  *

From aef649e7c07d285a19bdb49f2c7a8b2073670406 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Nowak?= <michaln@qualtrics.com>
Date: Mon, 26 Apr 2021 09:51:26 +0200
Subject: [PATCH 1953/2348] fix(index.d.ts): change document.validateSync
 return type to ValidationError

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index a2640d34948..ffdcfb9734f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -598,7 +598,7 @@ declare module 'mongoose' {
     validate(pathsToValidate: Array<string>, options: any, callback: (err: CallbackError) => void): void;
 
     /** Executes registered validation rules (skipping asynchronous validators) for this document. */
-    validateSync(pathsToValidate?: Array<string>, options?: any): NativeError | null;
+    validateSync(pathsToValidate?: Array<string>, options?: any): Error.ValidationError | null;
   }
 
   interface AcceptsDiscriminator {

From 97f851fb132ee776e73c24fb535f6722e8803838 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 26 Apr 2021 11:31:18 -0400
Subject: [PATCH 1954/2348] fix(query): convert projection string values to
 numbers as a workaround for #10142

---
 lib/query.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index e674f0edf6f..75d9191dd2a 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -946,7 +946,6 @@ Query.prototype.projection = function(arg) {
 Query.prototype.select = function select() {
   let arg = arguments[0];
   if (!arg) return this;
-  let i;
 
   if (arguments.length !== 1) {
     throw new Error('Invalid select: select only takes 1 argument');
@@ -961,9 +960,14 @@ Query.prototype.select = function select() {
 
   if (utils.isObject(arg)) {
     const keys = Object.keys(arg);
-    for (i = 0; i < keys.length; ++i) {
-      fields[keys[i]] = arg[keys[i]];
-      userProvidedFields[keys[i]] = arg[keys[i]];
+    for (let i = 0; i < keys.length; ++i) {
+      let value = arg[keys[i]];
+      // Workaround for gh-10142
+      if (typeof value === 'string') {
+        value = 1;
+      }
+      fields[keys[i]] = value;
+      userProvidedFields[keys[i]] = value;
     }
     return this;
   }

From 18a74b4aea3447a75f2358314888869b7b69f5b9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Nowak?= <michaln@qualtrics.com>
Date: Mon, 26 Apr 2021 09:44:48 +0200
Subject: [PATCH 1955/2348] fix(index.d.ts): add CastError constructor

---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index a2640d34948..24d54a26ad7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2665,6 +2665,8 @@ declare module 'mongoose' {
       path: string;
       reason?: NativeError | null;
       model?: any;
+
+      constructor(type: string, value: any, path: string, reason?: NativeError, schemaType?: SchemaType);
     }
 
     export class DisconnectedError extends Error {

From 78386c10535f166b97a5f041c580f2b5949943ea Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 14:54:24 -0400
Subject: [PATCH 1956/2348] chore: update opencollective sponsors

---
 index.pug | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.pug b/index.pug
index 1d0dd785a47..58df836fb53 100644
--- a/index.pug
+++ b/index.pug
@@ -353,10 +353,10 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/nathan-oscar898/257fa8f/avatar/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://slot-xo888.com/">
-                <img class="sponsor" src="https://images.opencollective.com/siwagorn/694a96c/avatar/256.png" style="height: 100px">
+                <img class="sponsor" src="https://images.opencollective.com/slotxo/694a96c/avatar/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://www.slotbar888.com/">
-                <img class="sponsor" src="https://images.opencollective.com/nathan-oscar989/2843cec/avatar/256.png" style="height: 100px">
+                <img class="sponsor" src="https://images.opencollective.com/slotbar/2843cec/avatar/256.png" style="height: 100px">
               </a>
             </div>
           </div>

From dca6ba7b8796fa25b41193a027642e8f6dce789a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 15:32:30 -0400
Subject: [PATCH 1957/2348] chore: update opencollective sponsors

---
 index.pug | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 58df836fb53..61cb6d11ad6 100644
--- a/index.pug
+++ b/index.pug
@@ -350,7 +350,7 @@ html(lang='en')
                 <img class="sponsor" src="https://images.opencollective.com/casino-martini/8efce1c/logo/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://ufa96bet.com/">
-                <img class="sponsor" src="https://images.opencollective.com/nathan-oscar898/257fa8f/avatar/256.png" style="height: 100px">
+                <img class="sponsor" src="https://images.opencollective.com/ufabet/257fa8f/avatar/256.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://slot-xo888.com/">
                 <img class="sponsor" src="https://images.opencollective.com/slotxo/694a96c/avatar/256.png" style="height: 100px">

From 54fda61ebfeeea8f0f527181de2edbe9166199b8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 16:11:16 -0400
Subject: [PATCH 1958/2348] fix(index.d.ts): allow any object as parameter to
 `create()` and `insertMany()`

Re: #10144
---
 index.d.ts | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index ffdcfb9734f..753d8e81aa9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -607,6 +607,8 @@ declare module 'mongoose' {
     discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
   }
 
+  interface AnyObject { [k: string]: any }
+
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
   interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
@@ -647,14 +649,14 @@ declare module 'mongoose' {
     countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
 
     /** Creates a new document or documents */
-    create(doc: T | DocumentDefinition<T>): Promise<T>;
-    create(docs: (T | DocumentDefinition<T>)[], options?: SaveOptions): Promise<T[]>;
-    create(docs: (T | DocumentDefinition<T>)[], callback: (err: CallbackError, docs: T[]) => void): void;
-    create(doc: T | DocumentDefinition<T>, callback: (err: CallbackError, doc: T) => void): void;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<T[]>;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: (err: CallbackError, docs: T[]) => void): void;
+    create(doc: T | DocumentDefinition<T> | AnyObject): Promise<T>;
+    create(doc: T | DocumentDefinition<T> | AnyObject, callback: (err: CallbackError, doc: T) => void): void;
     create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<T[]>;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: T[]) => void): void;
     create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
     create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: T[]) => void): void;
     create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: T) => void): void;
 
     /**
@@ -734,12 +736,12 @@ declare module 'mongoose' {
     init(callback?: (err: any) => void): Promise<T>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
-    insertMany(doc: T | DocumentDefinition<T>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
-    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions): Promise<T>;
-    insertMany(docs: Array<T | DocumentDefinition<T>>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
-    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions): Promise<Array<T>>;
-    insertMany(doc: T | DocumentDefinition<T>, options?: InsertManyOptions, callback?: (err: CallbackError, res: T | InsertManyResult) => void): void;
-    insertMany(docs: Array<T | DocumentDefinition<T>>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<T> | InsertManyResult) => void): void;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions): Promise<Array<T>>;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions): Promise<T>;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: (err: CallbackError, res: T | InsertManyResult) => void): void;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<T> | InsertManyResult) => void): void;
 
     /**
      * Lists the indexes currently defined in MongoDB. This may or may not be

From a42e10bf7b8c6715caa131ca4400ba0dcf06a322 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 16:38:58 -0400
Subject: [PATCH 1959/2348] refactor(index.d.ts): allow creating `Model` class
 with raw interface, no `extends Document` re: #10144

---
 index.d.ts                | 125 +++++++++++++++++++-------------------
 test/typescript/models.ts |  24 ++++++++
 2 files changed, 87 insertions(+), 62 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 753d8e81aa9..363c851f8b6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -100,7 +100,7 @@ declare module 'mongoose' {
    */
   export function isValidObjectId(v: any): boolean;
 
-  export function model<T extends Document>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
+  export function model<T>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
   export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
     name: string,
     schema?: Schema<T, U>,
@@ -608,11 +608,12 @@ declare module 'mongoose' {
   }
 
   interface AnyObject { [k: string]: any }
+  type EnforceDocument<T> = T extends Document ? T : T & Document;
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
-  interface Model<T extends Document, TQueryHelpers = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
-    new(doc?: T | any): T;
+  interface Model<T, TQueryHelpers = {}, TMethods = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
+    new(doc?: T | any): EnforceDocument<T>;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
     // eslint-disable-next-line @typescript-eslint/ban-types
@@ -641,31 +642,31 @@ declare module 'mongoose' {
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
+    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
+    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a new document or documents */
-    create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<T[]>;
-    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: (err: CallbackError, docs: T[]) => void): void;
-    create(doc: T | DocumentDefinition<T> | AnyObject): Promise<T>;
-    create(doc: T | DocumentDefinition<T> | AnyObject, callback: (err: CallbackError, doc: T) => void): void;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: T[]) => void): void;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<T>;
-    create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<T[]>;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: T) => void): void;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<EnforceDocument<T>[]>;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: (err: CallbackError, docs: EnforceDocument<T>[]) => void): void;
+    create(doc: T | DocumentDefinition<T> | AnyObject): Promise<EnforceDocument<T>>;
+    create(doc: T | DocumentDefinition<T> | AnyObject, callback: (err: CallbackError, doc: EnforceDocument<T>) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<EnforceDocument<T>[]>;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: EnforceDocument<T>[]) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<EnforceDocument<T>>;
+    create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<EnforceDocument<T>[]>;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: EnforceDocument<T>) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,
      * mongoose will not create the collection for the model until any documents are
      * created. Use this method to create the collection explicitly.
      */
-    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
-    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<T>) => void): void;
+    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<EnforceDocument<T>>>;
+    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<EnforceDocument<T>>) => void): void;
 
     /**
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
@@ -682,18 +683,18 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
-    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
-    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
+    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
+    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
-    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
-    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, T, TQueryHelpers>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
+    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
+    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
@@ -714,16 +715,16 @@ declare module 'mongoose' {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T> | null) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: T | null) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T> | null) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
      * The document returned has no paths marked as modified initially.
      */
-    hydrate(obj: any): T;
+    hydrate(obj: any): EnforceDocument<T>;
 
     /**
      * This function is responsible for building [indexes](https://docs.mongodb.com/manual/indexes/),
@@ -733,15 +734,15 @@ declare module 'mongoose' {
      * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
      * don't need to call it.
      */
-    init(callback?: (err: any) => void): Promise<T>;
+    init(callback?: (err: any) => void): Promise<EnforceDocument<T>>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
-    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions): Promise<Array<T>>;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions): Promise<Array<EnforceDocument<T>>>;
     insertMany(doc: T | DocumentDefinition<T> | AnyObject, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
-    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions): Promise<T>;
-    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: (err: CallbackError, res: T | InsertManyResult) => void): void;
-    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<T> | InsertManyResult) => void): void;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions): Promise<EnforceDocument<T>>;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: (err: CallbackError, res: EnforceDocument<T> | InsertManyResult) => void): void;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T>> | InsertManyResult) => void): void;
 
     /**
      * Lists the indexes currently defined in MongoDB. This may or may not be
@@ -757,9 +758,9 @@ declare module 'mongoose' {
 
     /** Populates document references. */
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: any, res: T[]) => void): Promise<Array<T>>;
+      callback?: (err: any, res: (EnforceDocument<T>)[]) => void): Promise<Array<EnforceDocument<T>>>;
     populate(doc: any, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: any, res: T) => void): Promise<T>;
+      callback?: (err: any, res: EnforceDocument<T>) => void): Promise<EnforceDocument<T>>;
 
     /**
      * Makes the indexes in MongoDB match the indexes defined in this model's
@@ -787,7 +788,7 @@ declare module 'mongoose' {
 
     /** Adds a `$where` clause to this query */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    $where(argument: string | Function): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
 
     /** Registered discriminators for this model. */
     discriminators: { [name: string]: Model<any> } | undefined;
@@ -796,10 +797,10 @@ declare module 'mongoose' {
     translateAliases(raw: any): any;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, T, TQueryHelpers>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, T, TQueryHelpers>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
 
     /**
      * Returns true if at least one document exists in the database that matches
@@ -809,38 +810,38 @@ declare module 'mongoose' {
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
-    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    find(callback?: (err: any, docs: EnforceDocument<T>[]) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: EnforceDocument<T>[]) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
-    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T>, res: any) => void): QueryWithHelpers<EnforceDocument<T>, EnforceDocument<T>, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T>, res: any) => void): QueryWithHelpers<EnforceDocument<T>, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T>, res: any) => void): QueryWithHelpers<EnforceDocument<T>, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T>>) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
@@ -848,10 +849,10 @@ declare module 'mongoose' {
       callback?: (err: any, res: any) => void
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, T, TQueryHelpers>;
+    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, T, TQueryHelpers>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T>, TQueryHelpers>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -860,18 +861,18 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T>, TQueryHelpers>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
-    where(path: string, val?: any): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
-    where(obj: object): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
-    where(): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
+    where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    where(obj: object): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    where(): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
   }
 
   type _UpdateWriteOpResult = mongodb.UpdateWriteOpResult['result'];
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index 49f7d140a23..d63b839cd43 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -14,6 +14,30 @@ function conventionalSyntax(): void {
   const bar = (SomeModel: Model<ITest>) => console.log(SomeModel);
 
   bar(Test);
+
+  const doc = new Test({ foo: '42' });
+  console.log(doc.foo);
+  doc.save();
+}
+
+function rawDocSyntax(): void {
+  interface ITest {
+    foo: string;
+  }
+
+  const TestSchema = new Schema<ITest & Document>({
+    foo: { type: String, required: true }
+  });
+
+  const Test = connection.model<ITest & Document>('Test', TestSchema);
+
+  const bar = (SomeModel: Model<ITest>) => console.log(SomeModel);
+
+  bar(Test);
+
+  const doc = new Test({ foo: '42' });
+  console.log(doc.foo);
+  doc.save();
 }
 
 function tAndDocSyntax(): void {

From f0a28eb6366e8b93c33b42e9b82c0314314d02f7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 16:59:09 -0400
Subject: [PATCH 1960/2348] refactor(index.d.ts): allow raw document as first
 generic param to Schema re: #10144

---
 index.d.ts | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 363c851f8b6..890920821d9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -101,7 +101,7 @@ declare module 'mongoose' {
   export function isValidObjectId(v: any): boolean;
 
   export function model<T>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
-  export function model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
+  export function model<T, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
     name: string,
     schema?: Schema<T, U>,
     collection?: string,
@@ -1081,7 +1081,7 @@ declare module 'mongoose' {
 
   type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
 
-  class Schema<DocType extends Document = Document, M extends Model<DocType, any> = Model<any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType = Document, M extends Model<DocType, any> = Model<any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1130,11 +1130,11 @@ declare module 'mongoose' {
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    method(name: string, fn: (this: DocType, ...args: any[]) => any, opts?: any): this;
-    method(obj: { [name: string]: (this: DocType, ...args: any[]) => any }): this;
+    method(name: string, fn: (this: EnforceDocument<DocType>, ...args: any[]) => any, opts?: any): this;
+    method(obj: { [name: string]: (this: EnforceDocument<DocType>, ...args: any[]) => any }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [name: string]: (this: DocType, ...args: any[]) => any };
+    methods: { [name: string]: (this: EnforceDocument<DocType>, ...args: any[]) => any };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1155,8 +1155,8 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema<DocType, Model<DocType>, SchemaDefinitionType>, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
@@ -1164,8 +1164,8 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
@@ -1174,8 +1174,8 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
-    pre<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
@@ -1184,7 +1184,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: <T extends QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>> = QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
+    query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;

From 9723b42df9ba937fafd8b2fd4ce472127385fe42 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 17:17:05 -0400
Subject: [PATCH 1961/2348] chore: release 5.12.6

---
 History.md   | 16 ++++++++++++++++
 package.json |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index eaf511d14dc..55312ed639e 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,19 @@
+5.12.6 / 2021-04-27
+===================
+ * fix(query): allow setting `writeConcern` schema option to work around MongoDB driver's `writeConcern` deprecation warning #10083 #10009 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(populate): dedupe when virtual populate foreignField is an array to avoid duplicate docs in result #10117
+ * fix(populate): add `localField` filter to `$elemMatch` on virtual populate when custom `match` has a `$elemMatch` and `foreignField` is an array #10117
+ * fix(query): convert projection string values to numbers as a workaround for #10142
+ * fix(document): set version key filter on `save()` when using `optimisticConcurrency` if no changes in document #10128 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(model): use `obj` as `context` in `Model.validate()` if `obj` is a document #10132
+ * fix(connection): avoid db events deprecation warning when using `useDb()` with `useUnifiedTopology` #8267
+ * fix: upgrade to sift@13.5.2 to work around transitive dev dependency security warning #10121
+ * fix(index.d.ts): allow any object as parameter to `create()` and `insertMany()` #10144
+ * fix(index.d.ts): clarify that `eachAsync()` callback receives a single doc rather than array of docs unless `batchSize` is set #10135
+ * fix(index.d.ts): clarify that return value from `validateSync()` is a ValidationError #10147 [michaln-q](https://github.com/michaln-q)
+ * fix(index.d.ts): add generic type for Model constructor #10074 [Duchynko](https://github.com/Duchynko)
+ * fix(index.d.ts): add parameter type in merge #10168 [yoonhoGo](https://github.com/yoonhoGo)
+
 5.12.5 / 2021-04-19
 ===================
  * fix(populate): handle populating underneath document array when document array property doesn't exist in db #10003
diff --git a/package.json b/package.json
index 673f6be0d44..4fed4d32408 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.5",
+  "version": "5.12.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 989a2b27a197ff64329be39e52441257a46b57bb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 20:29:10 -0400
Subject: [PATCH 1962/2348] test(document): repro #10141

---
 test/document.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 1f87fe7563e..39acebd1757 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10206,4 +10206,28 @@ describe('document', function() {
       assert.ok(resultObject.child.map instanceof Map);
     });
   });
+
+  it('does not double validate paths under mixed objects (gh-10141)', function() {
+    let validatorCallCount = 0;
+    const Test = db.model('Test', Schema({
+      name: String,
+      object: {
+        type: Object,
+        validate: () => {
+          validatorCallCount++;
+          return true;
+        }
+      }
+    }));
+
+    return co(function*() {
+      const doc = yield Test.create({ name: 'test', object: { answer: 42 } });
+
+      validatorCallCount = 0;
+      doc.set('object.question', 'secret');
+      doc.set('object.answer', 0);
+      yield doc.validate();
+      assert.equal(validatorCallCount, 0);
+    });
+  });
 });

From 6578af5864117c574bbe5089500f35c6babb3d32 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 20:29:26 -0400
Subject: [PATCH 1963/2348] fix(document): avoid double validating paths
 underneath mixed objects in save()

Fix #10141
Re: #4305
---
 lib/document.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 68cb7ae69d1..1f1b3d15b27 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -47,6 +47,7 @@ const documentSchemaSymbol = require('./helpers/symbols').documentSchemaSymbol;
 const getSymbol = require('./helpers/symbols').getSymbol;
 const populateModelSymbol = require('./helpers/symbols').populateModelSymbol;
 const scopeSymbol = require('./helpers/symbols').scopeSymbol;
+const schemaMixedSymbol = require('./schema/symbols').schemaMixedSymbol;
 
 let DocumentArray;
 let MongooseArray;
@@ -2496,6 +2497,11 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
         return;
       }
 
+      // If setting a path under a mixed path, avoid using the mixed path validator (gh-10141)
+      if (schemaType[schemaMixedSymbol] != null && path !== schemaType.path) {
+        return --total || complete();
+      }
+
       let val = _this.$__getValue(path);
 
       // If you `populate()` and get back a null value, required validators

From 27b7ddcbaa62ec81664a154ad529f04e151166fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 20:46:57 -0400
Subject: [PATCH 1964/2348] fix(index.d.ts): allow setting
 `mongoose.pluralize(null)` in TypeScript

Fix #10185
---
 index.d.ts              | 2 +-
 test/typescript/base.ts | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 753d8e81aa9..65d5e1fd942 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -125,7 +125,7 @@ declare module 'mongoose' {
   export function plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): typeof mongoose;
 
   /** Getter/setter around function for pluralizing collection names. */
-  export function pluralize(fn?: (str: string) => string): (str: string) => string;
+  export function pluralize(fn?: ((str: string) => string) | null): ((str: string) => string) | null;
 
   /** Sets mongoose options */
   export function set(key: string, value: any): void;
diff --git a/test/typescript/base.ts b/test/typescript/base.ts
index a663ef05e1b..4c7c9963b03 100644
--- a/test/typescript/base.ts
+++ b/test/typescript/base.ts
@@ -4,3 +4,5 @@ Object.values(mongoose.models).forEach(model => {
   model.modelName;
   model.findOne();
 });
+
+mongoose.pluralize(null);

From ba27c3f6dcc3cffdf30e630bedf2c0c9bd6f6dde Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 20:53:20 -0400
Subject: [PATCH 1965/2348] chore: disable eslint rule that's causing warnings
 in #10146

---
 package.json | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 4fed4d32408..38a605a69af 100644
--- a/package.json
+++ b/package.json
@@ -122,7 +122,8 @@
         "rules": {
           "@typescript-eslint/no-explicit-any": "off",
           "@typescript-eslint/ban-types": "off",
-          "@typescript-eslint/no-unused-vars": "off"
+          "@typescript-eslint/no-unused-vars": "off",
+          "@typescript-eslint/explicit-module-boundary-types": "off"
         }
       }
     ],

From 38d8c3924a3162dddfaea15c1bc32a6b5f64ab0b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 21:25:18 -0400
Subject: [PATCH 1966/2348] test(cursor): repro #10150

---
 test/query.cursor.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index 46751ab9cc1..b2ce61f9569 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -711,4 +711,26 @@ describe('QueryCursor', function() {
       assert.deepEqual(arr, ['KICKBOXER', 'IP MAN', 'ENTER THE DRAGON']);
     });
   });
+
+  it('reports CastError with noCursorTimeout set (gh-10150)', function() {
+    const schema = new mongoose.Schema({ name: String });
+    const Movie = db.model('Movie', schema);
+
+    return co(function*() {
+      yield Movie.deleteMany({});
+      yield Movie.create([
+        { name: 'Kickboxer' },
+        { name: 'Ip Man' },
+        { name: 'Enter the Dragon' }
+      ]);
+
+      const arr = [];
+      const err = yield Movie.find({ name: { lt: 'foo' } }).cursor().
+        addCursorFlag('noCursorTimeout', true).
+        eachAsync(doc => arr.push(doc.name)).
+        then(() => null, err => err);
+      assert.ok(err);
+      assert.equal(err.name, 'CastError');
+    });
+  });
 });

From c30120416e9d626a3335d54a27a6631f64e51bba Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 27 Apr 2021 21:25:29 -0400
Subject: [PATCH 1967/2348] fix(cursor): correctly report CastError when using
 `noCursorTimeout` flag

Fix #10150
---
 lib/cursor/QueryCursor.js | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index de38b820fea..e1c5ca75a5d 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -57,8 +57,12 @@ function QueryCursor(query, options) {
     }
     model.collection.find(query._conditions, this.options, function(err, cursor) {
       if (_this._error) {
-        cursor.close(function() {});
+        if (cursor != null) {
+          cursor.close(function() {});
+        }
+        _this.emit('cursor', null);
         _this.listeners('error').length > 0 && _this.emit('error', _this._error);
+        return;
       }
       if (err) {
         return _this.emit('error', err);
@@ -389,7 +393,10 @@ function _next(ctx, cb) {
       });
     }
   } else {
-    ctx.once('cursor', function() {
+    ctx.once('cursor', function(cursor) {
+      if (cursor == null) {
+        return;
+      }
       _next(ctx, cb);
     });
   }
@@ -470,7 +477,10 @@ function _waitForCursor(ctx, cb) {
   if (ctx.cursor) {
     return cb();
   }
-  ctx.once('cursor', function() {
+  ctx.once('cursor', function(cursor) {
+    if (cursor == null) {
+      return;
+    }
     cb();
   });
 }

From 06ffc8bd08a914af860c3224e18136d0476a9edf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 10:59:34 -0400
Subject: [PATCH 1968/2348] test(discriminator): repro #10157

---
 test/model.discriminator.test.js | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 54c5e7e169b..9beefe238ac 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1720,4 +1720,31 @@ describe('model', function() {
 
     assert.deepEqual(nestedDocument.body.children[1].body.children[0].body.children[0].body.children, []);
   });
+
+  it('takes discriminator schema\'s single nested over base schema\'s (gh-10157)', function() {  
+    const personSchema = new Schema({
+      name: Schema({ firstName: String, lastName: String }),
+       kind: { type: 'String', enum: ['normal', 'vip'], required: true },
+    }, { discriminatorKey: 'kind' });
+  
+    const Person = db.model('Person', personSchema);
+  
+    const vipSchema = Schema({
+      name: Schema({
+        firstName: { type: 'String', required: true },
+        title: { type: 'String', required: true }
+      })
+    });
+    const Vip = Person.discriminator('vip', vipSchema);
+
+    const doc1 = new Vip({ name: { firstName: 'John' } });
+    let err = doc1.validateSync();
+    assert.ok(err);
+    assert.ok(err.errors['name.title']);
+
+    const doc2 = new Vip({ name: { title: 'Dr' } });
+    err = doc2.validateSync();
+    assert.ok(err);
+    assert.ok(err.errors['name.firstName']);
+  });
 });

From 481b8e867405365a11bcdd5fde6887c1f96ac91f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 11:00:27 -0400
Subject: [PATCH 1969/2348] fix(discriminator): take discriminator schema's
 single nested paths over base schema's

Fix #10157
---
 lib/helpers/schema/merge.js      | 10 +++++++++-
 test/model.discriminator.test.js |  8 ++++----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/schema/merge.js b/lib/helpers/schema/merge.js
index d206500c440..b1f16356fcc 100644
--- a/lib/helpers/schema/merge.js
+++ b/lib/helpers/schema/merge.js
@@ -1,7 +1,15 @@
 'use strict';
 
 module.exports = function merge(s1, s2) {
-  s1.add(s2.tree || {});
+  const paths = Object.keys(s2.tree);
+  const pathsToAdd = {};
+  for (const key of paths) {
+    if (s1.paths[key] || s1.nested[key] || s1.singleNestedPaths[key]) {
+      continue;
+    }
+    pathsToAdd[key] = s2.tree[key];
+  }
+  s1.add(pathsToAdd);
 
   s1.callQueue = s1.callQueue.concat(s2.callQueue);
   s1.method(s2.methods);
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 9beefe238ac..2465826fbe6 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1721,14 +1721,14 @@ describe('model', function() {
     assert.deepEqual(nestedDocument.body.children[1].body.children[0].body.children[0].body.children, []);
   });
 
-  it('takes discriminator schema\'s single nested over base schema\'s (gh-10157)', function() {  
+  it('takes discriminator schema\'s single nested over base schema\'s (gh-10157)', function() {
     const personSchema = new Schema({
       name: Schema({ firstName: String, lastName: String }),
-       kind: { type: 'String', enum: ['normal', 'vip'], required: true },
+      kind: { type: 'String', enum: ['normal', 'vip'], required: true }
     }, { discriminatorKey: 'kind' });
-  
+
     const Person = db.model('Person', personSchema);
-  
+
     const vipSchema = Schema({
       name: Schema({
         firstName: { type: 'String', required: true },

From 75cfa6eeb79a9ff68a6bdc202073da571ae18e64 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 15:30:34 -0400
Subject: [PATCH 1970/2348] fix(model+query): consistently wrap query callbacks
 in `process.nextTick()` to avoid clean stack traces causing memory leak when
 using synchronous recursion like `async.whilst()`

Fix #9864
---
 lib/model.js | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index e708c79daa9..6da2a28b798 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4840,11 +4840,13 @@ Model.$handleCallbackError = function(callback) {
 
   const _this = this;
   return function() {
-    try {
-      callback.apply(null, arguments);
-    } catch (error) {
-      _this.emit('error', error);
-    }
+    process.nextTick(() => {
+      try {
+        callback.apply(null, arguments);
+      } catch (error) {
+        _this.emit('error', error);
+      }
+    });
   };
 };
 

From 6250b15a96bb83d3b8ee1db03b62b0424092d95d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 15:53:28 -0400
Subject: [PATCH 1971/2348] test(schema): repro #10164

---
 test/schema.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 08d3deef563..fd611e0dc62 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2594,4 +2594,18 @@ describe('schema', function() {
     assert.equal(testSchema.path('doesntpopulate.$').options.ref, 'features');
     assert.equal(testSchema.path('populatescorrectly.$').options.ref, 'features');
   });
+
+  it('path() gets single nested paths within document arrays (gh-10164)', function() {
+    const schema = mongoose.Schema({
+      field1: [mongoose.Schema({
+        field2: mongoose.Schema({
+          field3: Boolean
+        })
+      })]
+    });
+
+    assert.equal(schema.path('field1').instance, 'Array');
+    assert.equal(schema.path('field1.field2').instance, 'Embedded');
+    assert.equal(schema.path('field1.field2.field3').instance, 'Boolean');
+  });
 });

From 5c6359d3c91a8b58083f61d2414b343e9b992ac3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 15:53:50 -0400
Subject: [PATCH 1972/2348] fix(schema): allow `path()` to return single nested
 paths within document arrays

Fix #10164
---
 lib/schema.js | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 6c4cd1f1545..5e69f026bc9 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -778,9 +778,6 @@ Schema.prototype.path = function(path, obj) {
       schemaType.schema.subpaths[key].$isUnderneathDocArray = true;
     }
     for (const key of Object.keys(schemaType.schema.singleNestedPaths)) {
-      if (typeof schemaType.schema.singleNestedPaths[cleanPath] !== 'object') {
-        continue;
-      }
       this.subpaths[path + '.' + key] = schemaType.schema.singleNestedPaths[key];
       schemaType.schema.singleNestedPaths[key].$isUnderneathDocArray = true;
     }

From c1cedd8eb43dbb1c33fb845fb7aecb4ddff21fbc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 16:25:23 -0400
Subject: [PATCH 1973/2348] fix(discriminator): allow numbers and ObjectIds as
 tied values for discriminators

Fix #10130
---
 index.d.ts                                    |  4 +--
 .../areDiscriminatorValuesEqual.js            | 16 ++++++++++
 .../discriminator/getDiscriminatorByValue.js  | 12 ++++----
 .../getSchemaDiscriminatorByValue.js          |  4 ++-
 lib/helpers/model/discriminator.js            |  5 +++-
 test/model.discriminator.test.js              | 29 +++++++++++++++++++
 6 files changed, 60 insertions(+), 10 deletions(-)
 create mode 100644 lib/helpers/discriminator/areDiscriminatorValuesEqual.js

diff --git a/index.d.ts b/index.d.ts
index ff40c1963aa..50ba645b3fc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -603,8 +603,8 @@ declare module 'mongoose' {
 
   interface AcceptsDiscriminator {
     /** Adds a discriminator type. */
-    discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
-    discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
+    discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string | number | ObjectId): Model<D>;
+    discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
   }
 
   interface AnyObject { [k: string]: any }
diff --git a/lib/helpers/discriminator/areDiscriminatorValuesEqual.js b/lib/helpers/discriminator/areDiscriminatorValuesEqual.js
new file mode 100644
index 00000000000..87b2408e6db
--- /dev/null
+++ b/lib/helpers/discriminator/areDiscriminatorValuesEqual.js
@@ -0,0 +1,16 @@
+'use strict';
+
+const ObjectId = require('../../types/objectid');
+
+module.exports = function areDiscriminatorValuesEqual(a, b) {
+  if (typeof a === 'string' && typeof b === 'string') {
+    return a === b;
+  }
+  if (typeof a === 'number' && typeof b === 'number') {
+    return a === b;
+  }
+  if (a instanceof ObjectId && b instanceof ObjectId) {
+    return a.toString() === b.toString();
+  }
+  return false;
+};
\ No newline at end of file
diff --git a/lib/helpers/discriminator/getDiscriminatorByValue.js b/lib/helpers/discriminator/getDiscriminatorByValue.js
index a107a910492..741fb8cd02f 100644
--- a/lib/helpers/discriminator/getDiscriminatorByValue.js
+++ b/lib/helpers/discriminator/getDiscriminatorByValue.js
@@ -1,5 +1,7 @@
 'use strict';
 
+const areDiscriminatorValuesEqual = require('./areDiscriminatorValuesEqual');
+
 /*!
 * returns discriminator by discriminatorMapping.value
 *
@@ -8,20 +10,18 @@
 */
 
 module.exports = function getDiscriminatorByValue(model, value) {
-  let discriminator = null;
   if (!model.discriminators) {
-    return discriminator;
+    return null;
   }
   for (const name in model.discriminators) {
     const it = model.discriminators[name];
     if (
       it.schema &&
       it.schema.discriminatorMapping &&
-      it.schema.discriminatorMapping.value == value
+      areDiscriminatorValuesEqual(it.schema.discriminatorMapping.value, value)
     ) {
-      discriminator = it;
-      break;
+      return it;
     }
   }
-  return discriminator;
+  return null;
 };
\ No newline at end of file
diff --git a/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js b/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js
index f3e71a093a9..b29fb6521e1 100644
--- a/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js
+++ b/lib/helpers/discriminator/getSchemaDiscriminatorByValue.js
@@ -1,5 +1,7 @@
 'use strict';
 
+const areDiscriminatorValuesEqual = require('./areDiscriminatorValuesEqual');
+
 /*!
 * returns discriminator by discriminatorMapping.value
 *
@@ -16,7 +18,7 @@ module.exports = function getSchemaDiscriminatorByValue(schema, value) {
     if (discriminatorSchema.discriminatorMapping == null) {
       continue;
     }
-    if (discriminatorSchema.discriminatorMapping.value === value) {
+    if (areDiscriminatorValuesEqual(discriminatorSchema.discriminatorMapping.value, value)) {
       return discriminatorSchema;
     }
   }
diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index 2ad4c5e3754..455d17de2f9 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const Mixed = require('../../schema/mixed');
+const ObjectId = require('../../types/objectid');
 const defineKey = require('../document/compile').defineKey;
 const get = require('../get');
 const utils = require('../../utils');
@@ -63,7 +64,9 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
   }
 
   let value = name;
-  if (typeof tiedValue == 'string' && tiedValue.length) {
+  if ((typeof tiedValue === 'string' && tiedValue.length) ||
+      typeof tiedValue === 'number' ||
+      tiedValue instanceof ObjectId) {
     value = tiedValue;
   }
 
diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 2465826fbe6..18ea0f91317 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1094,6 +1094,35 @@ describe('model', function() {
         });
     });
 
+    it('supports ObjectId as tied value (gh-10130)', function() {
+      const eventSchema = new Schema({ message: String, kind: 'ObjectId' },
+        { discriminatorKey: 'kind' });
+
+      const Event = db.model('Event', eventSchema);
+      const clickedId = new mongoose.Types.ObjectId();
+      const purchasedId = new mongoose.Types.ObjectId();
+      Event.discriminator('Clicked', new Schema({
+        element: String
+      }), clickedId);
+      Event.discriminator('Purchased', new Schema({
+        product: String
+      }), purchasedId);
+
+      return co(function*() {
+        yield Event.create([
+          { message: 'test', element: '#buy', kind: clickedId },
+          { message: 'test2', product: 'Turbo Man', kind: purchasedId }
+        ]);
+
+        const docs = yield Event.find().sort({ message: 1 });
+        assert.equal(docs.length, 2);
+        assert.equal(docs[0].kind.toHexString(), clickedId.toHexString());
+        assert.equal(docs[0].element, '#buy');
+        assert.equal(docs[1].kind.toHexString(), purchasedId.toHexString());
+        assert.equal(docs[1].product, 'Turbo Man');
+      });
+    });
+
     it('Embedded discriminators in nested doc arrays (gh-6202)', function() {
       const eventSchema = new Schema({ message: String }, {
         discriminatorKey: 'kind',

From 06c6a8b9aaf00888e0adb7206b769a9b396bbb3d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 16:53:20 -0400
Subject: [PATCH 1974/2348] refactor(discriminator): don't rely on `model` when
 getting discriminator by value

Re: #10130
---
 lib/helpers/discriminator/getConstructor.js          | 2 +-
 lib/helpers/discriminator/getDiscriminatorByValue.js | 8 ++++----
 lib/helpers/model/castBulkWrite.js                   | 2 +-
 lib/helpers/populate/getModelsMapForPopulate.js      | 2 +-
 lib/helpers/query/getEmbeddedDiscriminatorPath.js    | 2 +-
 lib/model.js                                         | 4 ++--
 lib/query.js                                         | 4 ++--
 lib/queryhelpers.js                                  | 2 +-
 lib/schema/array.js                                  | 2 +-
 lib/types/documentarray.js                           | 4 ++--
 10 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/lib/helpers/discriminator/getConstructor.js b/lib/helpers/discriminator/getConstructor.js
index 04a3dedd83a..728da3b25ff 100644
--- a/lib/helpers/discriminator/getConstructor.js
+++ b/lib/helpers/discriminator/getConstructor.js
@@ -14,7 +14,7 @@ module.exports = function getConstructor(Constructor, value) {
     if (Constructor.discriminators[value[discriminatorKey]]) {
       Constructor = Constructor.discriminators[value[discriminatorKey]];
     } else {
-      const constructorByValue = getDiscriminatorByValue(Constructor, value[discriminatorKey]);
+      const constructorByValue = getDiscriminatorByValue(Constructor.discriminators, value[discriminatorKey]);
       if (constructorByValue) {
         Constructor = constructorByValue;
       }
diff --git a/lib/helpers/discriminator/getDiscriminatorByValue.js b/lib/helpers/discriminator/getDiscriminatorByValue.js
index 741fb8cd02f..099aaefddfd 100644
--- a/lib/helpers/discriminator/getDiscriminatorByValue.js
+++ b/lib/helpers/discriminator/getDiscriminatorByValue.js
@@ -9,12 +9,12 @@ const areDiscriminatorValuesEqual = require('./areDiscriminatorValuesEqual');
 * @param {string} value
 */
 
-module.exports = function getDiscriminatorByValue(model, value) {
-  if (!model.discriminators) {
+module.exports = function getDiscriminatorByValue(discriminators, value) {
+  if (discriminators == null) {
     return null;
   }
-  for (const name in model.discriminators) {
-    const it = model.discriminators[name];
+  for (const name of Object.keys(discriminators)) {
+    const it = discriminators[name];
     if (
       it.schema &&
       it.schema.discriminatorMapping &&
diff --git a/lib/helpers/model/castBulkWrite.js b/lib/helpers/model/castBulkWrite.js
index d3f0e9a2e1d..54559b5686a 100644
--- a/lib/helpers/model/castBulkWrite.js
+++ b/lib/helpers/model/castBulkWrite.js
@@ -218,7 +218,7 @@ function _addDiscriminatorToObject(schema, obj) {
 function decideModelByObject(model, object) {
   const discriminatorKey = model.schema.options.discriminatorKey;
   if (object != null && object.hasOwnProperty(discriminatorKey)) {
-    model = getDiscriminatorByValue(model, object[discriminatorKey]) || model;
+    model = getDiscriminatorByValue(model.discriminators, object[discriminatorKey]) || model;
   }
   return model;
 }
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 5dcdfd5d155..74d036a29e0 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -409,7 +409,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
       if (!schema && discriminatorKey && (discriminatorValue = utils.getValue(discriminatorKey, doc))) {
         // `modelNameForFind` is the discriminator value, so we might need
         // find the discriminated model name
-        const discriminatorModel = getDiscriminatorByValue(model, discriminatorValue) || model;
+        const discriminatorModel = getDiscriminatorByValue(model.discriminators, discriminatorValue) || model;
         if (discriminatorModel != null) {
           modelForCurrentDoc = discriminatorModel;
         } else {
diff --git a/lib/helpers/query/getEmbeddedDiscriminatorPath.js b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
index f4dc839b9c7..2f3f39d97e0 100644
--- a/lib/helpers/query/getEmbeddedDiscriminatorPath.js
+++ b/lib/helpers/query/getEmbeddedDiscriminatorPath.js
@@ -69,7 +69,7 @@ module.exports = function getEmbeddedDiscriminatorPath(schema, update, filter, p
         continue;
       }
 
-      const discriminatorSchema = getDiscriminatorByValue(schematype.caster, discriminatorKey).schema;
+      const discriminatorSchema = getDiscriminatorByValue(schematype.caster.discriminators, discriminatorKey).schema;
 
       const rest = parts.slice(i + 1).join('.');
       schematype = discriminatorSchema.path(rest);
diff --git a/lib/model.js b/lib/model.js
index 6da2a28b798..3bb4f38ede7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3051,7 +3051,7 @@ Model.create = function create(doc, options, callback) {
     args.forEach(doc => {
       toExecute.push(callback => {
         const Model = this.discriminators && doc[discriminatorKey] != null ?
-          this.discriminators[doc[discriminatorKey]] || getDiscriminatorByValue(this, doc[discriminatorKey]) :
+          this.discriminators[doc[discriminatorKey]] || getDiscriminatorByValue(this.discriminators, doc[discriminatorKey]) :
           this;
         if (Model == null) {
           throw new MongooseError(`Discriminator "${doc[discriminatorKey]}" not ` +
@@ -4688,7 +4688,7 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
 
       // If discriminator key is set, use the discriminator instead (gh-7586)
       const Discriminator = model.discriminators[doc[discriminatorKey]] ||
-        getDiscriminatorByValue(model, doc[discriminatorKey]);
+        getDiscriminatorByValue(model.discriminators, doc[discriminatorKey]);
       if (Discriminator != null) {
         return new Discriminator(doc, fields, skipId);
       }
diff --git a/lib/query.js b/lib/query.js
index 9cc6e64fd40..46f8cce76d1 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -4651,7 +4651,7 @@ Query.prototype._castUpdate = function _castUpdate(obj, overwrite) {
       typeof filter[schema.options.discriminatorKey] !== 'object' &&
       schema.discriminators != null) {
     const discriminatorValue = filter[schema.options.discriminatorKey];
-    const byValue = getDiscriminatorByValue(this.model, discriminatorValue);
+    const byValue = getDiscriminatorByValue(this.model.discriminators, discriminatorValue);
     schema = schema.discriminators[discriminatorValue] ||
       (byValue && byValue.schema) ||
       schema;
@@ -4869,7 +4869,7 @@ Query.prototype.cast = function(model, obj) {
   const discriminatorKey = model.schema.options.discriminatorKey;
   if (obj != null &&
       obj.hasOwnProperty(discriminatorKey)) {
-    model = getDiscriminatorByValue(model, obj[discriminatorKey]) || model;
+    model = getDiscriminatorByValue(model.discriminators, obj[discriminatorKey]) || model;
   }
 
   try {
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index 79f4dc50a5e..cf475a7e234 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -97,7 +97,7 @@ exports.createModel = function createModel(model, doc, fields, userProvidedField
 
   const value = doc[key];
   if (key && value && model.discriminators) {
-    const discriminator = model.discriminators[value] || getDiscriminatorByValue(model, value);
+    const discriminator = model.discriminators[value] || getDiscriminatorByValue(model.discriminators, value);
     if (discriminator) {
       const _fields = clone(userProvidedFields);
       exports.applyPaths(_fields, discriminator.schema);
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 93d26741d32..88dea5a6241 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -471,7 +471,7 @@ SchemaArray.prototype.castForQuery = function($conditional, value) {
           Constructor.discriminators[val[Constructor.schema.options.discriminatorKey]]) {
         Constructor = Constructor.discriminators[val[Constructor.schema.options.discriminatorKey]];
       } else {
-        const constructorByValue = getDiscriminatorByValue(Constructor, val[Constructor.schema.options.discriminatorKey]);
+        const constructorByValue = getDiscriminatorByValue(Constructor.discriminators, val[Constructor.schema.options.discriminatorKey]);
         if (constructorByValue) {
           Constructor = constructorByValue;
         }
diff --git a/lib/types/documentarray.js b/lib/types/documentarray.js
index be533b9f549..90d2637269d 100644
--- a/lib/types/documentarray.js
+++ b/lib/types/documentarray.js
@@ -96,7 +96,7 @@ class CoreDocumentArray extends CoreMongooseArray {
           Constructor.discriminators[value[Constructor.schema.options.discriminatorKey]]) {
         Constructor = Constructor.discriminators[value[Constructor.schema.options.discriminatorKey]];
       } else {
-        const constructorByValue = getDiscriminatorByValue(Constructor, value[Constructor.schema.options.discriminatorKey]);
+        const constructorByValue = getDiscriminatorByValue(Constructor.discriminators, value[Constructor.schema.options.discriminatorKey]);
         if (constructorByValue) {
           Constructor = constructorByValue;
         }
@@ -289,7 +289,7 @@ class CoreDocumentArray extends CoreMongooseArray {
           Constructor.discriminators[obj[Constructor.schema.options.discriminatorKey]]) {
         Constructor = Constructor.discriminators[obj[Constructor.schema.options.discriminatorKey]];
       } else {
-        const constructorByValue = getDiscriminatorByValue(Constructor, obj[Constructor.schema.options.discriminatorKey]);
+        const constructorByValue = getDiscriminatorByValue(Constructor.discriminators, obj[Constructor.schema.options.discriminatorKey]);
         if (constructorByValue) {
           Constructor = constructorByValue;
         }

From 37916168834265b73686bd990e63a3fb828cdbb9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 21:53:31 -0400
Subject: [PATCH 1975/2348] test(document): repro #10148

---
 test/document.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 39acebd1757..4221a972ccc 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -9911,6 +9911,30 @@ describe('document', function() {
     });
   });
 
+  it('with virtual populate (gh-10148)', function() {
+    const childSchema = Schema({ name: String, parentId: 'ObjectId' });
+    childSchema.virtual('parent', {
+      ref: 'Parent',
+      localField: 'parentId',
+      foreignField: '_id',
+      justOne: true
+    });
+    const Child = db.model('Child', childSchema);
+
+    const Parent = db.model('Parent', Schema({ name: String }));
+
+    return co(function*() {
+      const p = yield Parent.create({ name: 'Anakin' });
+      yield Child.create({ name: 'Luke', parentId: p._id });
+
+      const res = yield Child.findOne().populate('parent');
+      assert.equal(res.parent.name, 'Anakin');
+      const docs = res.$getPopulatedDocs();
+      assert.equal(docs.length, 1);
+      assert.equal(docs[0].name, 'Anakin');
+    });
+  });
+
   it('handles paths named `db` (gh-9798)', function() {
     const schema = new Schema({
       db: String

From d8785f16a1464b802bbceb9dd379efcf4f4f9bc3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 21:53:44 -0400
Subject: [PATCH 1976/2348] fix(document): make `$getPopulatedDocs()` return
 populated virtuals

Fix #10148
---
 lib/document.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 1f1b3d15b27..1114602a773 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3933,7 +3933,13 @@ Document.prototype.populate = function populate() {
  * @instance
  */
 Document.prototype.$getPopulatedDocs = function $getPopulatedDocs() {
-  const keys = (Object.keys(this.$__.populated));
+  let keys = [];
+  if (this.$__.populated != null) {
+    keys = keys.concat(Object.keys(this.$__.populated));
+  }
+  if (this.$$populatedVirtuals != null) {
+    keys = keys.concat(Object.keys(this.$$populatedVirtuals));
+  }
   let result = [];
   for (const key of keys) {
     const value = this.get(key);

From e961cb7e9599459d422641470934df29295a1532 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Apr 2021 22:26:29 -0400
Subject: [PATCH 1977/2348] docs: make headers linkable via clicking

Fix #10156
---
 docs/deprecations.pug | 18 +++++++++---------
 docs/documents.pug    | 12 ++++++------
 docs/jest.pug         |  6 +++---
 docs/plugins.pug      |  2 +-
 docs/transactions.pug |  8 ++++----
 5 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/docs/deprecations.pug b/docs/deprecations.pug
index dea93a31b55..2531d3f7bd3 100644
--- a/docs/deprecations.pug
+++ b/docs/deprecations.pug
@@ -27,7 +27,7 @@ block content
     around these deprecation warnings, but you need to test whether these options
     cause any problems for your application. Please [report any issues on GitHub](https://github.com/Automattic/mongoose/issues/new).
 
-    ## Summary
+    <h2 id="summary"><a href="#summary">Summary</a></h2>
 
     To fix all deprecation warnings, follow the below steps:
 
@@ -41,7 +41,7 @@ block content
 
     Read below for more a more detailed description of each deprecation warning.
 
-    ## The `useNewUrlParser` Option
+    <h2 id="the-usenewurlparser-option"><a href="#the-usenewurlparser-option">The <code>useNewUrlParser</code> Option</a></h2>
 
     By default, `mongoose.connect()` will print out the below warning:
 
@@ -76,7 +76,7 @@ block content
     connected, the URL parser is no longer important. If you can't connect
     with `{ useNewUrlParser: true }`, please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
 
-    ## `findAndModify()`
+    <h2 id="findandmodify"><a href="#findandmodify"><code>findAndModify()</code></a></h2>
 
     If you use [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate),
     by default you'll see one of the below deprecation warnings.
@@ -117,7 +117,7 @@ block content
     * [`Query.findOneAndRemove()`](/docs/api.html#query_Query-findOneAndRemove)
     * [`Query.findOneAndUpdate()`](/docs/api.html#query_Query-findOneAndUpdate)
 
-    ## `ensureIndex()`
+    <h2 id="ensureindex"><a href="#ensureindex"><code>ensureIndex()</code></a></h2>
 
     If you define [indexes in your Mongoose schemas](https://mongoosejs.com/docs/guide.html#indexes), you'll see the below
     deprecation warning.
@@ -145,7 +145,7 @@ block content
     this option on without any code changes. If you discover any issues,
     please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
 
-    ## `remove()`
+    <h2 id="remove"><a href="#remove"><code>remove()</code></a></h2>
 
     The MongoDB driver's [`remove()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove) is deprecated in favor of `deleteOne()` and `deleteMany()`. This is to comply with
     the [MongoDB CRUD specification](https://github.com/mongodb/specifications/blob/master/source/crud/crud.rst),
@@ -174,7 +174,7 @@ block content
     MyModel.deleteOne({ answer: 42 });
     ```
 
-    ## `useUnifiedTopology`
+    <h2 id="useunifiedtopology"><a href="#useunifiedtopology"><code>useUnifiedTopology</code></a></h2>
 
     By default, `mongoose.connect()` will print out the below warning:
 
@@ -210,7 +210,7 @@ block content
 
     If you find any unexpected behavior, please [open up an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
 
-    ## `update()`
+    <h2 id="update"><a href="#update"><code>update()</code></a></h2>
 
     Like `remove()`, the [`update()` function](/docs/api.html#model_Model.update) is deprecated in favor
     of the more explicit [`updateOne()`](/docs/api.html#model_Model.updateOne), [`updateMany()`](/docs/api.html#model_Model.updateMany), and [`replaceOne()`](/docs/api.html#model_Model.replaceOne) functions. You should replace
@@ -238,7 +238,7 @@ block content
     MyModel.updateMany(filter, update);
     ```
 
-    ## `count()`
+    <h2 id="count"><a href="#count"><code>count()</code></a></h2>
 
     The MongoDB server has deprecated the `count()` function in favor of two
     separate functions, [`countDocuments()`](#query_Query-countDocuments) and
@@ -281,7 +281,7 @@ block content
     MyModel.find().estimatedDocumentCount().exec();
     ```
 
-    ## `GridStore`
+    <h2 id="gridstore"><a href="#gridstore"><code>GridStore</code></a></h2>
 
     If you're using [gridfs-stream](https://www.npmjs.com/package/gridfs-stream),
     you'll see the below deprecation warning:
diff --git a/docs/documents.pug b/docs/documents.pug
index 5ac1d1f7965..9ec93979979 100644
--- a/docs/documents.pug
+++ b/docs/documents.pug
@@ -35,7 +35,7 @@ block content
       <li><a href="#overwriting">Overwriting</a></li>
     </ul>
 
-    ### Documents vs Models
+    <h2 id="documents-vs-models"><a href="#documents-vs-models">Documents vs Models</a></h2>
 
     [Document](api.html#Document) and [Model](api.html#Model) are distinct
     classes in Mongoose. The Model class is a subclass of the Document class.
@@ -55,7 +55,7 @@ block content
     You should not have to create an instance of the Document class without
     going through a model.
 
-    ### Retrieving
+    <h2 id="retrieving"><a href="#retrieving">Retrieving</a></h2>
 
     When you load documents from MongoDB using model functions like [`findOne()`](api.html#model_Model.findOne),
     you get a Mongoose document back.
@@ -68,7 +68,7 @@ block content
     doc instanceof mongoose.Document; // true
     ```
 
-    ### Updating Using `save()`
+    <h2 id="updating-using-save"><a href="#updating-using-save">Updating Using <code>save()</code></a></h2>
 
     Mongoose documents track changes. You can modify a document using vanilla
     JavaScript assignments and Mongoose will convert it into [MongoDB update operators](https://docs.mongodb.com/manual/reference/operator/update/).
@@ -103,7 +103,7 @@ block content
     await doc.save(); // Throws DocumentNotFoundError
     ```
 
-    ### Updating Using Queries
+    <h2 id="updating-using-queries"><a href="#updating-using-queries">Updating Using Queries</a></h2>
 
     The [`save()`](api.html#model_Model-save) function is generally the right
     way to update a document with Mongoose. With `save()`, you get full
@@ -122,7 +122,7 @@ block content
     execute `save()` middleware. If you need save middleware and full validation,
     first query for the document and then `save()` it._
 
-    ### Validating
+    <h2 id="validating"><a href="#validating">Validating</a></h2>
 
     Documents are casted and validated before they are saved. Mongoose first casts
     values to the specified type and then validates them. Internally, Mongoose
@@ -158,7 +158,7 @@ block content
 
     Read the [validation](./validation.html) guide for more details.
 
-    ### Overwriting
+    <h2 id="overwriting"><a href="#overwriting">Overwriting</a></h2>
 
     There are 2 different ways to overwrite a document (replacing all keys in the
     document). One way is to use the
diff --git a/docs/jest.pug b/docs/jest.pug
index ca70187c2ce..2b54cecb8d8 100644
--- a/docs/jest.pug
+++ b/docs/jest.pug
@@ -31,7 +31,7 @@ block content
     If you choose to delve into dangerous waters and test Mongoose apps with
     Jest, here's what you need to know:
 
-    ## Recommended `testEnvironment`
+    <h2 id="recommended-testenvironment"><a href="#recommended-testenvironment">Recommended <code>testEnvironment</code></a></h2>
 
     Do **not** use Jest's default [`jsdom` test environment](https://jestjs.io/docs/en/configuration.html#testenvironment-string)
     when testing Mongoose apps, _unless_ you are explicitly testing an
@@ -54,7 +54,7 @@ block content
     };
     ```
 
-    ## Timer Mocks
+    <h2 id="timer-mocks"><a href="#timer-mocks">Timer Mocks</a></h2>
 
     Absolutely do **not** use [timer mocks](https://jestjs.io/docs/en/timer-mocks.html)
     when testing Mongoose apps. Fake timers stub out global functions like
@@ -88,7 +88,7 @@ block content
     sinon.stub(time, 'setTimeout');
     ```
 
-    ## `globalSetup` and `globalTeardown`
+    <h2 id="globalsetup-and-globalteardown"><a href="#globalsetup-and-globalteardown"><code>globalSetup</code> and <code>globalTeardown</code></a></h2>
 
     Do **not** use `globalSetup` to call `mongoose.connect()` or
     `mongoose.createConnection()`. Jest runs `globalSetup` in
diff --git a/docs/plugins.pug b/docs/plugins.pug
index 0c8208740c2..844ae43707c 100644
--- a/docs/plugins.pug
+++ b/docs/plugins.pug
@@ -31,7 +31,7 @@ block content
       <li><a href="#official">Officially Supported Plugins</a></li>
     </ul>
 
-    ### Example
+    <h3 id="example"><a href="#example">Example</a></h3>
 
     Plugins are a tool for reusing logic in multiple schemas. Suppose you have
     several models in your database and want to add a `loadedAt` property
diff --git a/docs/transactions.pug b/docs/transactions.pug
index a5ec5ddd7ee..df31b1590d6 100644
--- a/docs/transactions.pug
+++ b/docs/transactions.pug
@@ -27,7 +27,7 @@ block content
     in isolation and potentially undo all the operations if one of them fails.
     This guide will get you started using transactions with Mongoose.
 
-    ## Getting Started with Transactions
+    <h2 id="getting-started-with-transactions"><a href="#getting-started-with-transactions">Getting Started with Transactions</a></h2>
 
     To create a transaction, you first need to create a session using or [`Mongoose#startSession`](/docs/api/mongoose.html#mongoose_Mongoose-startSession)
     or [`Connection#startSession()`](/docs/api/connection.html#connection_Connection-startSession).
@@ -59,7 +59,7 @@ block content
     [require:transactions.*can save document after aborted transaction]
     ```
 
-    ## With Mongoose Documents and `save()`
+    <h2 id="with-mongoose-documents-and-save"><a href="#with-mongoose-documents-and-save">With Mongoose Documents and <code>save()</code></a></h2>
 
     If you get a [Mongoose document](/docs/documents.html) from [`findOne()`](/docs/api.html#findone_findOne)
     or [`find()`](/docs/api.html#find_find) using a session, the document will
@@ -71,7 +71,7 @@ block content
     [require:transactions.*save]
     ```
 
-    ## With the Aggregation Framework
+    <h2 id="with-the-aggregation-framework"><a href="#with-the-aggregation-framework">With the Aggregation Framework</a></h2>
 
     The `Model.aggregate()` function also supports transactions. Mongoose
     aggregations have a [`session()` helper](/docs/api.html#aggregate_Aggregate-session)
@@ -82,7 +82,7 @@ block content
     [require:transactions.*aggregate]
     ```
 
-    ## Advanced Usage
+    <h2 id="advanced-usage"><a href="#advanced-usage">Advanced Usage</a></h2>
 
     Advanced users who want more fine-grained control over when they commit or abort transactions
     can use `session.startTransaction()` to start a transaction:

From 3fa78b60f523fa31cde6a00ab131a56495d2addc Mon Sep 17 00:00:00 2001
From: Joost De Cock <joost@joost.at>
Date: Thu, 29 Apr 2021 10:04:49 +0200
Subject: [PATCH 1978/2348] Fix: broken link in document.js

This links to an anchor, but the target is on a different page, so this link is broken.

I checked the other links to see how to link, but there are three different approaches used throughout the docs:

 - Relative links: `/docs/api/model.html#model_Model.replaceOne`
 - http links: `http://mongoosejs.com/docs/api/model.html#model_Model.replaceOne`
 - https links: `https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne`

I opted for the https link (`https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne`) since that seemed like the best choice to me.
---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 1114602a773..9fb65857669 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -805,7 +805,7 @@ Document.prototype.updateOne = function updateOne(doc, options, callback) {
  *
  * ####Valid options:
  *
- *  - same as in [Model.replaceOne](#model_Model.replaceOne)
+ *  - same as in [Model.replaceOne](https://mongoosejs.com/docs/api/model.html#model_Model.replaceOne)
  *
  * @see Model.replaceOne #model_Model.replaceOne
  * @param {Object} doc

From 777e756bddbc301e8b8aff7289353faba4543a7c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Apr 2021 10:06:07 -0400
Subject: [PATCH 1979/2348] fix(index.d.ts): allow using raw document with
 TMethods generic in model definition

Re: #10144
---
 index.d.ts                | 153 +++++++++++++++++++-------------------
 test/typescript/models.ts |  13 +++-
 2 files changed, 87 insertions(+), 79 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 890920821d9..980f6b37706 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -101,7 +101,7 @@ declare module 'mongoose' {
   export function isValidObjectId(v: any): boolean;
 
   export function model<T>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
-  export function model<T, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
+  export function model<T, U extends Model<T, TQueryHelpers, any>, TQueryHelpers = {}>(
     name: string,
     schema?: Schema<T, U>,
     collection?: string,
@@ -244,8 +244,8 @@ declare module 'mongoose' {
     models: { [index: string]: Model<any> };
 
     /** Defines or retrieves a model. */
-    model<T extends Document>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
-    model<T extends Document, U extends Model<T, TQueryHelpers>, TQueryHelpers = {}>(
+    model<T>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
+    model<T, U extends Model<T, TQueryHelpers, any>, TQueryHelpers = {}>(
       name: string,
       schema?: Schema<T, U, TQueryHelpers>,
       collection?: string,
@@ -367,7 +367,7 @@ declare module 'mongoose' {
     getIndexes(): any;
   }
 
-  class Document<T = any, TQueryHelpers = {}> {
+  class Document<T = any, TQueryHelpers = any> {
     constructor(doc?: T | any);
 
     /** This documents _id. */
@@ -608,12 +608,12 @@ declare module 'mongoose' {
   }
 
   interface AnyObject { [k: string]: any }
-  type EnforceDocument<T> = T extends Document ? T : T & Document;
+  type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document & TMethods;
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
   interface Model<T, TQueryHelpers = {}, TMethods = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
-    new(doc?: T | any): EnforceDocument<T>;
+    new(doc?: T | any): EnforceDocument<T, TMethods>;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
     // eslint-disable-next-line @typescript-eslint/ban-types
@@ -642,31 +642,31 @@ declare module 'mongoose' {
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
+    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
+    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a new document or documents */
-    create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<EnforceDocument<T>[]>;
-    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: (err: CallbackError, docs: EnforceDocument<T>[]) => void): void;
-    create(doc: T | DocumentDefinition<T> | AnyObject): Promise<EnforceDocument<T>>;
-    create(doc: T | DocumentDefinition<T> | AnyObject, callback: (err: CallbackError, doc: EnforceDocument<T>) => void): void;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<EnforceDocument<T>[]>;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: EnforceDocument<T>[]) => void): void;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<EnforceDocument<T>>;
-    create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<EnforceDocument<T>[]>;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: EnforceDocument<T>) => void): void;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<EnforceDocument<T, TMethods>[]>;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): void;
+    create(doc: T | DocumentDefinition<T> | AnyObject): Promise<EnforceDocument<T, TMethods>>;
+    create(doc: T | DocumentDefinition<T> | AnyObject, callback: (err: CallbackError, doc: EnforceDocument<T, TMethods>) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<EnforceDocument<T, TMethods>[]>;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<EnforceDocument<T, TMethods>>;
+    create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<EnforceDocument<T, TMethods>[]>;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: EnforceDocument<T, TMethods>) => void): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,
      * mongoose will not create the collection for the model until any documents are
      * created. Use this method to create the collection explicitly.
      */
-    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<EnforceDocument<T>>>;
-    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<EnforceDocument<T>>) => void): void;
+    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<EnforceDocument<T, TMethods>>>;
+    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<EnforceDocument<T, TMethods>>) => void): void;
 
     /**
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
@@ -683,18 +683,18 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
-    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
-    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
-    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
-    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T>, TQueryHelpers>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
@@ -715,16 +715,16 @@ declare module 'mongoose' {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T> | null) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T> | null) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
      * The document returned has no paths marked as modified initially.
      */
-    hydrate(obj: any): EnforceDocument<T>;
+    hydrate(obj: any): EnforceDocument<T, TMethods>;
 
     /**
      * This function is responsible for building [indexes](https://docs.mongodb.com/manual/indexes/),
@@ -734,15 +734,15 @@ declare module 'mongoose' {
      * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
      * don't need to call it.
      */
-    init(callback?: (err: any) => void): Promise<EnforceDocument<T>>;
+    init(callback?: (err: any) => void): Promise<EnforceDocument<T, TMethods>>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
-    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions): Promise<Array<EnforceDocument<T>>>;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions): Promise<Array<EnforceDocument<T, TMethods>>>;
     insertMany(doc: T | DocumentDefinition<T> | AnyObject, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
-    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions): Promise<EnforceDocument<T>>;
-    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: (err: CallbackError, res: EnforceDocument<T> | InsertManyResult) => void): void;
-    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T>> | InsertManyResult) => void): void;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions): Promise<EnforceDocument<T, TMethods>>;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: (err: CallbackError, res: EnforceDocument<T, TMethods> | InsertManyResult) => void): void;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>> | InsertManyResult) => void): void;
 
     /**
      * Lists the indexes currently defined in MongoDB. This may or may not be
@@ -758,9 +758,9 @@ declare module 'mongoose' {
 
     /** Populates document references. */
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: any, res: (EnforceDocument<T>)[]) => void): Promise<Array<EnforceDocument<T>>>;
+      callback?: (err: any, res: (EnforceDocument<T, TMethods>)[]) => void): Promise<Array<EnforceDocument<T, TMethods>>>;
     populate(doc: any, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: any, res: EnforceDocument<T>) => void): Promise<EnforceDocument<T>>;
+      callback?: (err: any, res: EnforceDocument<T, TMethods>) => void): Promise<EnforceDocument<T, TMethods>>;
 
     /**
      * Makes the indexes in MongoDB match the indexes defined in this model's
@@ -788,7 +788,7 @@ declare module 'mongoose' {
 
     /** Adds a `$where` clause to this query */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    $where(argument: string | Function): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Registered discriminators for this model. */
     discriminators: { [name: string]: Model<any> } | undefined;
@@ -797,10 +797,10 @@ declare module 'mongoose' {
     translateAliases(raw: any): any;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T>, TQueryHelpers>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T>, TQueryHelpers>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /**
      * Returns true if at least one document exists in the database that matches
@@ -810,38 +810,38 @@ declare module 'mongoose' {
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: EnforceDocument<T>[]) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
-    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: EnforceDocument<T>[]) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    find(callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
-    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T>, res: any) => void): QueryWithHelpers<EnforceDocument<T>, EnforceDocument<T>, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T>, res: any) => void): QueryWithHelpers<EnforceDocument<T>, EnforceDocument<T>, TQueryHelpers>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T>, res: any) => void): QueryWithHelpers<EnforceDocument<T>, EnforceDocument<T>, TQueryHelpers>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T> | null, EnforceDocument<T>, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T>>) => void): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>>) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
@@ -849,10 +849,10 @@ declare module 'mongoose' {
       callback?: (err: any, res: any) => void
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T>, TQueryHelpers>;
+    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T>, TQueryHelpers>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -861,18 +861,18 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T>, TQueryHelpers>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T>, TQueryHelpers>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T>, TQueryHelpers>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
-    where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
-    where(obj: object): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
-    where(): QueryWithHelpers<Array<EnforceDocument<T>>, EnforceDocument<T>, TQueryHelpers>;
+    where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    where(obj: object): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    where(): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
   }
 
   type _UpdateWriteOpResult = mongodb.UpdateWriteOpResult['result'];
@@ -1080,8 +1080,9 @@ declare module 'mongoose' {
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
   type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
+  type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
-  class Schema<DocType = Document, M extends Model<DocType, any> = Model<any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1130,11 +1131,11 @@ declare module 'mongoose' {
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    method(name: string, fn: (this: EnforceDocument<DocType>, ...args: any[]) => any, opts?: any): this;
-    method(obj: { [name: string]: (this: EnforceDocument<DocType>, ...args: any[]) => any }): this;
+    method(name: string, fn: (this: EnforceDocument<DocType, ExtractMethods<M>>, ...args: any[]) => any, opts?: any): this;
+    method(obj: { [name: string]: (this: EnforceDocument<DocType, ExtractMethods<M>>, ...args: any[]) => any }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [name: string]: (this: EnforceDocument<DocType>, ...args: any[]) => any };
+    methods: { [name: string]: (this: EnforceDocument<DocType, ExtractMethods<M>>, ...args: any[]) => any };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1155,8 +1156,8 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema<DocType, Model<DocType>, SchemaDefinitionType>, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
@@ -1164,8 +1165,8 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
 
-    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
@@ -1174,8 +1175,8 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
 
     /** Defines a pre hook for the model. */
-    pre<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
-    pre<T = EnforceDocument<DocType>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
+    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
@@ -1184,7 +1185,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
+    query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index d63b839cd43..b522d619470 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -25,18 +25,25 @@ function rawDocSyntax(): void {
     foo: string;
   }
 
-  const TestSchema = new Schema<ITest & Document>({
+  interface ITestMethods {
+    bar(): number;
+  }
+
+  type TestModel = Model<ITest, {}, ITestMethods>;
+
+  const TestSchema = new Schema<ITest, TestModel>({
     foo: { type: String, required: true }
   });
 
-  const Test = connection.model<ITest & Document>('Test', TestSchema);
+  const Test = connection.model<ITest, TestModel>('Test', TestSchema);
 
-  const bar = (SomeModel: Model<ITest>) => console.log(SomeModel);
+  const bar = (SomeModel: Model<any, any, any>) => console.log(SomeModel);
 
   bar(Test);
 
   const doc = new Test({ foo: '42' });
   console.log(doc.foo);
+  console.log(doc.bar());
   doc.save();
 }
 

From 2a21efe6a68e8c80a5679dd9a145612fcabffd8a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Apr 2021 12:21:35 -0400
Subject: [PATCH 1980/2348] docs: add link to transactions guide from nav bar

Fix #10143
---
 docs/layout.pug | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/layout.pug b/docs/layout.pug
index 19dd84ce0a7..52889b0b849 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -97,6 +97,8 @@ html(lang='en')
                 a.pure-menu-link(href="/docs/discriminators.html", class=outputUrl === '/docs/discriminators.html' ? 'selected' : '') Discriminators
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/plugins.html", class=outputUrl === '/docs/plugins.html' ? 'selected' : '') Plugins
+              li.pure-menu-item.sub-item
+                a.pure-menu-link(href="/docs/transactions.html", class=outputUrl === '/docs/transactions.html' ? 'selected' : '') Transactions
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
               li.pure-menu-item.sub-item

From 62ba2071586b357f48542ac2d3265ca0865f9c24 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Apr 2021 12:38:15 -0400
Subject: [PATCH 1981/2348] docs(validation): add section about custom error
 messages

Fix #10140
---
 test/docs/validation.test.js | 41 ++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 50d1268c9df..f2088caa142 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -112,6 +112,47 @@ describe('validation docs', function() {
     // acquit:ignore:end
   });
 
+  /**
+   * You can configure the error message for individual validators in your schema. There are two equivalent
+   * ways to set the validator error message:
+   *
+   * - Array syntax: `min: [6, 'Must be at least 6, got {VALUE}']`
+   * - Object syntax: `enum: { values: ['Coffee', 'Tea'], message: '{VALUE} is not supported' }`
+   *
+   * Mongoose also supports rudimentary templating for error messages.
+   * Mongoose replaces `{VALUE}` with the value being validated.
+   */
+
+  it('Custom Error Messages', function(done) {
+    const breakfastSchema = new Schema({
+      eggs: {
+        type: Number,
+        min: [6, 'Must be at least 6, got {VALUE}'],
+        max: 12
+      },
+      drink: {
+        type: String,
+        enum: {
+          values: ['Coffee', 'Tea'],
+          message: '{VALUE} is not supported'
+        }
+      }
+    });
+    const Breakfast = db.model('Breakfast', breakfastSchema);
+
+    const badBreakfast = new Breakfast({
+      eggs: 2,
+      drink: 'Milk'
+    });
+    let error = badBreakfast.validateSync();
+    assert.equal(error.errors['eggs'].message,
+      'Must be at least 6, got 2');
+    assert.equal(error.errors['drink'].message, 'Milk is not supported');
+    // acquit:ignore:start
+    done();
+    // acquit:ignore:end
+  });
+
   /**
    * A common gotcha for beginners is that the `unique` option for schemas
    * is *not* a validator. It's a convenient helper for building [MongoDB unique indexes](https://docs.mongodb.com/manual/core/index-unique/).

From 8f31786c6875f5493c17cf1f390adefcbe617b2e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Apr 2021 12:50:36 -0400
Subject: [PATCH 1982/2348] chore: release 5.12.7

---
 History.md   | 17 +++++++++++++++++
 package.json |  2 +-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 55312ed639e..15bdf208ddd 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,20 @@
+5.12.7 / 2021-04-29
+===================
+ * fix(document): make $getPopulatedDocs() return populated virtuals #10148
+ * fix(discriminator): take discriminator schema's single nested paths over base schema's #10157
+ * fix(discriminator): allow numbers and ObjectIds as tied values for discriminators #10130
+ * fix(document): avoid double validating paths underneath mixed objects in save() #10141
+ * fix(schema): allow path() to return single nested paths within document arrays #10164
+ * fix(model+query): consistently wrap query callbacks in `process.nextTick()` to avoid clean stack traces causing memory leak when using synchronous recursion like `async.whilst()` #9864
+ * fix(cursor): correctly report CastError when using noCursorTimeout flag #10150
+ * fix(index.d.ts): add CastError constructor #10176
+ * fix(index.d.ts): allow setting mongoose.pluralize(null) in TypeScript #10185
+ * docs: add link to transactions guide from nav bar #10143
+ * docs(validation): add section about custom error messages #10140
+ * docs: make headers linkable via clicking #10156
+ * docs: broken link in document.js #10190 [joostdecock](https://github.com/joostdecock)
+ * docs: make navbar responsive on legacy 2.x docs #10171 [ad99526](https://github.com/ad99526)
+
 5.12.6 / 2021-04-27
 ===================
  * fix(query): allow setting `writeConcern` schema option to work around MongoDB driver's `writeConcern` deprecation warning #10083 #10009 [IslandRhythms](https://github.com/IslandRhythms)
diff --git a/package.json b/package.json
index 38a605a69af..3fadc9860f2 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.6",
+  "version": "5.12.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 09de820cdf5d1317433b53ce3c5a42eb5d649ae8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Apr 2021 12:52:41 -0400
Subject: [PATCH 1983/2348] test: fix tests

---
 test/docs/validation.test.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index f2088caa142..8304d4d067e 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -138,6 +138,9 @@ describe('validation docs', function() {
         }
       }
     });
+    // acquit:ignore:start
+    db.deleteModel(/Breakfast/);
+    // acquit:ignore:end
     const Breakfast = db.model('Breakfast', breakfastSchema);
 
     const badBreakfast = new Breakfast({

From 1b0b7649f96f326cc34c5e2a8582296f5cb27c06 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 29 Apr 2021 18:54:12 -0400
Subject: [PATCH 1984/2348] chore: remove unnecessary driver dynamic imports so
 Mongoose can work with Parcel

Re: #9603
---
 lib/drivers/browser/index.js             |  3 +++
 lib/drivers/node-mongodb-native/index.js |  3 ++-
 lib/index.js                             | 17 ++++++-----------
 3 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/lib/drivers/browser/index.js b/lib/drivers/browser/index.js
index 56d0b8a75c9..bc4ac5f6b28 100644
--- a/lib/drivers/browser/index.js
+++ b/lib/drivers/browser/index.js
@@ -8,6 +8,9 @@ exports.Binary = require('./binary');
 exports.Collection = function() {
   throw new Error('Cannot create a collection from browser library');
 };
+exports.getConnection = () => function() {
+  throw new Error('Cannot create a connection from browser library');
+};
 exports.Decimal128 = require('./decimal128');
 exports.ObjectId = require('./objectid');
 exports.ReadPreference = require('./ReadPreference');
diff --git a/lib/drivers/node-mongodb-native/index.js b/lib/drivers/node-mongodb-native/index.js
index 2cd749e274d..2ed9eb0a5bc 100644
--- a/lib/drivers/node-mongodb-native/index.js
+++ b/lib/drivers/node-mongodb-native/index.js
@@ -8,4 +8,5 @@ exports.Binary = require('./binary');
 exports.Collection = require('./collection');
 exports.Decimal128 = require('./decimal128');
 exports.ObjectId = require('./objectid');
-exports.ReadPreference = require('./ReadPreference');
\ No newline at end of file
+exports.ReadPreference = require('./ReadPreference');
+exports.getConnection = () => require('./connection');
\ No newline at end of file
diff --git a/lib/index.js b/lib/index.js
index 31ebcc01e15..ff42be3bebf 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -27,6 +27,7 @@ const Types = require('./types');
 const Query = require('./query');
 const Model = require('./model');
 const applyPlugins = require('./helpers/schema/applyPlugins');
+const driver = require('./driver');
 const get = require('./helpers/get');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
 const legacyPluralize = require('mongoose-legacy-pluralize');
@@ -127,8 +128,8 @@ Mongoose.prototype.cast = cast;
 Mongoose.prototype.STATES = STATES;
 
 /**
- * The underlying driver this Mongoose instance uses to communicate with
- * the database. A driver is a Mongoose-specific interface that defines functions
+ * Object with `get()` and `set()` containing the underlying driver this Mongoose instance
+ * uses to communicate with the database. A driver is a Mongoose-specific interface that defines functions
  * like `find()`.
  *
  * @memberOf Mongoose
@@ -136,7 +137,7 @@ Mongoose.prototype.STATES = STATES;
  * @api public
  */
 
-Mongoose.prototype.driver = require('./driver');
+Mongoose.prototype.driver = driver;
 
 /**
  * Sets mongoose options
@@ -735,23 +736,17 @@ Mongoose.prototype.__defineSetter__('connection', function(v) {
 
 Mongoose.prototype.connections;
 
-/*!
- * Driver dependent APIs
- */
-
-const driver = global.MONGOOSE_DRIVER_PATH || './drivers/node-mongodb-native';
-
 /*!
  * Connection
  */
 
-const Connection = require(driver + '/connection');
+const Connection = driver.get().getConnection();
 
 /*!
  * Collection
  */
 
-const Collection = require(driver + '/collection');
+const Collection = driver.get().Collection;
 
 /**
  * The Mongoose Aggregate constructor

From 474b4be752ddb50e9532b2c236f02fd289f4835d Mon Sep 17 00:00:00 2001
From: "John H. Kohler" <jhunterkohler@gmail.com>
Date: Mon, 3 May 2021 01:37:48 -0400
Subject: [PATCH 1985/2348] Added Document.prototype.parent to type def

---
 index.d.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 50ba645b3fc..bf812684de8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -542,6 +542,12 @@ declare module 'mongoose' {
      */
     overwrite(obj: DocumentDefinition<this>): this;
 
+    /**
+     * If this document is a subdocument or populated document, returns the 
+     * document's parent. Returns undefined otherwise.
+     */
+    parent(): Document | undefined;
+
     /**
      * Populates document references, executing the `callback` when complete.
      * If you want to use promises instead, use this function with

From 62e28413cc589f7fa9abcc1480a6110157fab0c1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 3 May 2021 13:05:02 -0400
Subject: [PATCH 1986/2348] chore: update opencollective sponsors

---
 index.pug | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/index.pug b/index.pug
index 61cb6d11ad6..6cd9cb816b2 100644
--- a/index.pug
+++ b/index.pug
@@ -280,9 +280,6 @@ html(lang='en')
               <a rel="sponsored" href="https://onlinecasinoinformatie.com/">
                 <img class="sponsor" src="https://images.opencollective.com/ricardo-goncalves/3275f75/avatar/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://onlinecasinoplatz.com/">
-                <img class="sponsor" src="https://images.opencollective.com/onlinecasinoplatz-com/8f8b647/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.turtlebet.com/fi/kaikki-nettikasinot.html">
                 <img class="sponsor" src="https://images.opencollective.com/turtlebet-nettikasinot/4799a27/logo/256.png" style="height: 100px">
               </a>
@@ -337,9 +334,6 @@ html(lang='en')
               <a rel="sponsored" href="https://www.nettikasinot.media/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-media/2dba7da/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://kajino.com/">
-                <img class="sponsor" src="https://images.opencollective.com/kajino-com/02c99ee/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://www.leoboost.com/buy-instagram-likes">
                 <img class="sponsor" src="https://images.opencollective.com/leo-boost1/f744783/logo/256.png" style="height: 100px">
               </a>

From b1892e5e9499871faf9849914dd8a5984743bf7a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 4 May 2021 07:00:28 +0200
Subject: [PATCH 1987/2348] chore(workflows): add node 16 to github actions

---
 .github/workflows/test.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 96519ae8a18..9c1b78b454e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node: [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]
+        node: [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]
     name: Node ${{ matrix.node }}
     steps:
       - uses: actions/checkout@v2

From d15129e7402e7c903167d2023f3f6143e9240abf Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 13:20:05 -0400
Subject: [PATCH 1988/2348] added test

---
 test/errors.validation.test.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 68c378840e1..82c2a08f712 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -9,6 +9,8 @@ const start = require('./common');
 
 const ValidationError = require('../lib/error/validation');
 const assert = require('assert');
+const { constant } = require('async');
+const co = require('co');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -257,4 +259,19 @@ describe('ValidationError', function() {
       });
     });
   });
+  it('should have error name in Cast error gh-10166', function(done) {
+    const testSchema = new Schema({text: {type:String, required: [true, "Text is required"]}, number: {
+      type: Number, required: [true, "Number is required"]}, });
+    const Test = mongoose.model('Test', testSchema);
+    const entry = new Test({"text": false, "number": "fsfsf"});
+      entry.validate(function(error) {
+        console.log(JSON.parse(JSON.stringify(error.errors.number)));
+        // wtf
+        console.log(JSON.parse(JSON.stringify(error.errors.number.message)))
+        console.log(JSON.parse(JSON.stringify(error.errors.number.name)))
+        assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
+        assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
+      });
+    done();
+  });
 });

From fff5317ad94c44f27d5186ff5d72c68fa42cfc2f Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 13:57:15 -0400
Subject: [PATCH 1989/2348] update

---
 lib/error/cast.js              | 13 +++++++++++--
 test/errors.validation.test.js |  7 +------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index c6ff277086c..e4f421565d8 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -41,6 +41,8 @@ class CastError extends MongooseError {
     this.value = value;
     this.path = path;
     this.reason = reason;
+    this.name = CastError.prototype.name;
+    this._message = CastError.prototype.message;
   }
 
   /*!
@@ -55,6 +57,8 @@ class CastError extends MongooseError {
     this.path = other.path;
     this.reason = other.reason;
     this.message = other.message;
+    this.name = CastError.prototype.name;
+    this._message = CastError.prototype.message;
   }
 
   /*!
@@ -68,7 +72,8 @@ class CastError extends MongooseError {
 }
 
 Object.defineProperty(CastError.prototype, 'name', {
-  value: 'CastError'
+  value: 'CastError',
+  writable: true
 });
 
 function getStringValue(value) {
@@ -97,6 +102,7 @@ function formatMessage(model, kind, stringValue, path, messageFormat) {
       replace('{KIND}', kind).
       replace('{VALUE}', stringValue).
       replace('{PATH}', path);
+      replace('{NAME}', name);
     if (model != null) {
       ret = ret.replace('{MODEL}', model.modelName);
     }
@@ -108,7 +114,10 @@ function formatMessage(model, kind, stringValue, path, messageFormat) {
     if (model != null) {
       ret += ' for model "' + model.modelName + '"';
     }
-
+    Object.defineProperty(CastError.prototype, 'message', {
+      value: ret,
+      writable: true
+    });
     return ret;
   }
 }
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 82c2a08f712..f5b1711e1ea 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -9,8 +9,6 @@ const start = require('./common');
 
 const ValidationError = require('../lib/error/validation');
 const assert = require('assert');
-const { constant } = require('async');
-const co = require('co');
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
@@ -266,10 +264,7 @@ describe('ValidationError', function() {
     const entry = new Test({"text": false, "number": "fsfsf"});
       entry.validate(function(error) {
         console.log(JSON.parse(JSON.stringify(error.errors.number)));
-        // wtf
-        console.log(JSON.parse(JSON.stringify(error.errors.number.message)))
-        console.log(JSON.parse(JSON.stringify(error.errors.number.name)))
-        assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
+        assert.ok(JSON.parse(JSON.stringify(error.errors.number._message)));
         assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
       });
     done();

From 573b74b1f0cc29d009a28877874dff7642d62a36 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:20:09 -0400
Subject: [PATCH 1990/2348] fix

---
 lib/error/cast.js              | 11 ++++-------
 test/errors.validation.test.js |  2 +-
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index e4f421565d8..99654b5335b 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -31,6 +31,10 @@ class CastError extends MongooseError {
     }
   }
 
+  toJSON() {
+    return {stringValue: this.stringValue, kind: this.kind, value: this.value, path: this.path, reason: this.reason, name: this.name, message: this.message}
+  }
+
   /*!
    * ignore
    */
@@ -42,7 +46,6 @@ class CastError extends MongooseError {
     this.path = path;
     this.reason = reason;
     this.name = CastError.prototype.name;
-    this._message = CastError.prototype.message;
   }
 
   /*!
@@ -56,9 +59,7 @@ class CastError extends MongooseError {
     this.value = other.value;
     this.path = other.path;
     this.reason = other.reason;
-    this.message = other.message;
     this.name = CastError.prototype.name;
-    this._message = CastError.prototype.message;
   }
 
   /*!
@@ -114,10 +115,6 @@ function formatMessage(model, kind, stringValue, path, messageFormat) {
     if (model != null) {
       ret += ' for model "' + model.modelName + '"';
     }
-    Object.defineProperty(CastError.prototype, 'message', {
-      value: ret,
-      writable: true
-    });
     return ret;
   }
 }
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index f5b1711e1ea..26eb179fd52 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -264,7 +264,7 @@ describe('ValidationError', function() {
     const entry = new Test({"text": false, "number": "fsfsf"});
       entry.validate(function(error) {
         console.log(JSON.parse(JSON.stringify(error.errors.number)));
-        assert.ok(JSON.parse(JSON.stringify(error.errors.number._message)));
+        assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
         assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
       });
     done();

From 93e7fd220acdd2e097d741dc33ef8d86d7dde93c Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:25:25 -0400
Subject: [PATCH 1991/2348] linter fixes

---
 lib/error/cast.js              |  3 +--
 test/errors.validation.test.js | 13 ++++++-------
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 99654b5335b..0763c0b9df8 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -32,7 +32,7 @@ class CastError extends MongooseError {
   }
 
   toJSON() {
-    return {stringValue: this.stringValue, kind: this.kind, value: this.value, path: this.path, reason: this.reason, name: this.name, message: this.message}
+    return { stringValue: this.stringValue, kind: this.kind, value: this.value, path: this.path, reason: this.reason, name: this.name, message: this.message };
   }
 
   /*!
@@ -103,7 +103,6 @@ function formatMessage(model, kind, stringValue, path, messageFormat) {
       replace('{KIND}', kind).
       replace('{VALUE}', stringValue).
       replace('{PATH}', path);
-      replace('{NAME}', name);
     if (model != null) {
       ret = ret.replace('{MODEL}', model.modelName);
     }
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 26eb179fd52..030c6758c6a 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -258,14 +258,13 @@ describe('ValidationError', function() {
     });
   });
   it('should have error name in Cast error gh-10166', function(done) {
-    const testSchema = new Schema({text: {type:String, required: [true, "Text is required"]}, number: {
-      type: Number, required: [true, "Number is required"]}, });
+    const testSchema = new Schema({ text: { type: String, required: [true, 'Text is required']}, number: {
+      type: Number, required: [true, 'Number is required'] } });
     const Test = mongoose.model('Test', testSchema);
-    const entry = new Test({"text": false, "number": "fsfsf"});
-      entry.validate(function(error) {
-        console.log(JSON.parse(JSON.stringify(error.errors.number)));
-        assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
-        assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
+    const entry = new Test({ 'text': false, 'number': 'fsfsf' });
+    entry.validate(function(error) {
+      assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
+      assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
       });
     done();
   });

From 24f6d3b389bbeffcd09e5f1c45f336f43ab95020 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:28:24 -0400
Subject: [PATCH 1992/2348] lint

---
 test/errors.validation.test.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 030c6758c6a..ae2124e71d4 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -258,14 +258,14 @@ describe('ValidationError', function() {
     });
   });
   it('should have error name in Cast error gh-10166', function(done) {
-    const testSchema = new Schema({ text: { type: String, required: [true, 'Text is required']}, number: {
+    const testSchema = new Schema({ text: { type: String, required: [true, 'Text is required'] }, number: {
       type: Number, required: [true, 'Number is required'] } });
     const Test = mongoose.model('Test', testSchema);
-    const entry = new Test({ 'text': false, 'number': 'fsfsf' });
+    const entry = new Test({ text: false, number: 'fsfsf' });
     entry.validate(function(error) {
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
-      });
+    });
     done();
   });
 });

From adbea75d28fb5ca613ccf7f49f3aa9c9a70b4ac0 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:32:54 -0400
Subject: [PATCH 1993/2348] Update cast.js

---
 lib/error/cast.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 0763c0b9df8..9ff29bc341f 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -45,7 +45,7 @@ class CastError extends MongooseError {
     this.value = value;
     this.path = path;
     this.reason = reason;
-    this.name = CastError.prototype.name;
+    // this.name = CastError.prototype.name;
   }
 
   /*!

From f3874a3b239e2d1bb7ced2fd8fb77551910c3856 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:33:05 -0400
Subject: [PATCH 1994/2348] Update cast.js

---
 lib/error/cast.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 9ff29bc341f..286c116aa20 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -59,7 +59,7 @@ class CastError extends MongooseError {
     this.value = other.value;
     this.path = other.path;
     this.reason = other.reason;
-    this.name = CastError.prototype.name;
+    // this.name = CastError.prototype.name;
   }
 
   /*!

From 0459e8be5183316d9f88b05a86fde539b8659a70 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:37:54 -0400
Subject: [PATCH 1995/2348] Update cast.js

---
 lib/error/cast.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 286c116aa20..e56f1311e55 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -30,11 +30,11 @@ class CastError extends MongooseError {
       super(formatMessage());
     }
   }
-
+  /*
   toJSON() {
     return { stringValue: this.stringValue, kind: this.kind, value: this.value, path: this.path, reason: this.reason, name: this.name, message: this.message };
   }
-
+  */
   /*!
    * ignore
    */
@@ -45,7 +45,7 @@ class CastError extends MongooseError {
     this.value = value;
     this.path = path;
     this.reason = reason;
-    // this.name = CastError.prototype.name;
+    this.name = CastError.prototype.name;
   }
 
   /*!
@@ -59,7 +59,7 @@ class CastError extends MongooseError {
     this.value = other.value;
     this.path = other.path;
     this.reason = other.reason;
-    // this.name = CastError.prototype.name;
+    this.name = CastError.prototype.name;
   }
 
   /*!

From c2a00f1b49df2c306ec277004eb6607289d313d7 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:42:01 -0400
Subject: [PATCH 1996/2348] check

---
 lib/error/cast.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index e56f1311e55..8bfee5becbf 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -45,7 +45,7 @@ class CastError extends MongooseError {
     this.value = value;
     this.path = path;
     this.reason = reason;
-    this.name = CastError.prototype.name;
+    // this.name = CastError.prototype.name;
   }
 
   /*!
@@ -59,7 +59,7 @@ class CastError extends MongooseError {
     this.value = other.value;
     this.path = other.path;
     this.reason = other.reason;
-    this.name = CastError.prototype.name;
+    // this.name = CastError.prototype.name;
   }
 
   /*!

From 6f269d8c98a059dc34adcf54201f9b8cfb167ceb Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:46:13 -0400
Subject: [PATCH 1997/2348] final check

---
 lib/error/cast.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index 8bfee5becbf..f17c140bdb8 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -74,7 +74,6 @@ class CastError extends MongooseError {
 
 Object.defineProperty(CastError.prototype, 'name', {
   value: 'CastError',
-  writable: true
 });
 
 function getStringValue(value) {

From 302f18feefe8e8fcb05fb7729fb7bcd51dbc7980 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:52:29 -0400
Subject: [PATCH 1998/2348] change model name to fix possible errors

---
 lib/error/cast.js              | 2 +-
 test/errors.validation.test.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index f17c140bdb8..f7f80f2092f 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -73,7 +73,7 @@ class CastError extends MongooseError {
 }
 
 Object.defineProperty(CastError.prototype, 'name', {
-  value: 'CastError',
+  value: 'CastError'
 });
 
 function getStringValue(value) {
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index ae2124e71d4..2e05f73d8b9 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -260,7 +260,7 @@ describe('ValidationError', function() {
   it('should have error name in Cast error gh-10166', function(done) {
     const testSchema = new Schema({ text: { type: String, required: [true, 'Text is required'] }, number: {
       type: Number, required: [true, 'Number is required'] } });
-    const Test = mongoose.model('Test', testSchema);
+    const Zeta = mongoose.model('Zeta', testSchema);
     const entry = new Test({ text: false, number: 'fsfsf' });
     entry.validate(function(error) {
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));

From 3c2ae2f9a193eb3433c4a9877f26bddb8e2fc09f Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:53:14 -0400
Subject: [PATCH 1999/2348] fix

---
 test/errors.validation.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 2e05f73d8b9..9d733b33a07 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -261,7 +261,7 @@ describe('ValidationError', function() {
     const testSchema = new Schema({ text: { type: String, required: [true, 'Text is required'] }, number: {
       type: Number, required: [true, 'Number is required'] } });
     const Zeta = mongoose.model('Zeta', testSchema);
-    const entry = new Test({ text: false, number: 'fsfsf' });
+    const entry = new Zeta({ text: false, number: 'fsfsf' });
     entry.validate(function(error) {
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));

From 7b361fe420868297d18c43673ab79bc3b9dac70c Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 14:57:40 -0400
Subject: [PATCH 2000/2348] Update errors.validation.test.js

---
 test/errors.validation.test.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 9d733b33a07..3217839d6c9 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -258,11 +258,12 @@ describe('ValidationError', function() {
     });
   });
   it('should have error name in Cast error gh-10166', function(done) {
-    const testSchema = new Schema({ text: { type: String, required: [true, 'Text is required'] }, number: {
+    const zetaSchema = new Schema({ text: { type: String, required: [true, 'Text is required'] }, number: {
       type: Number, required: [true, 'Number is required'] } });
-    const Zeta = mongoose.model('Zeta', testSchema);
+    const Zeta = mongoose.model('Zeta', zetaSchema);
     const entry = new Zeta({ text: false, number: 'fsfsf' });
     entry.validate(function(error) {
+      console.log(JSON.parse(JSON.stringify(error)));
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
     });

From 7c39d348a7e2fd0b806b49fdf3e486d5adc57231 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 6 May 2021 15:17:54 -0400
Subject: [PATCH 2001/2348] true fix

---
 lib/error/cast.js              | 5 +----
 test/errors.validation.test.js | 1 -
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index f7f80f2092f..c41b703a572 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -30,11 +30,9 @@ class CastError extends MongooseError {
       super(formatMessage());
     }
   }
-  /*
   toJSON() {
     return { stringValue: this.stringValue, kind: this.kind, value: this.value, path: this.path, reason: this.reason, name: this.name, message: this.message };
   }
-  */
   /*!
    * ignore
    */
@@ -45,7 +43,6 @@ class CastError extends MongooseError {
     this.value = value;
     this.path = path;
     this.reason = reason;
-    // this.name = CastError.prototype.name;
   }
 
   /*!
@@ -59,7 +56,7 @@ class CastError extends MongooseError {
     this.value = other.value;
     this.path = other.path;
     this.reason = other.reason;
-    // this.name = CastError.prototype.name;
+    this.message = other.message;
   }
 
   /*!
diff --git a/test/errors.validation.test.js b/test/errors.validation.test.js
index 3217839d6c9..ebb884a6c97 100644
--- a/test/errors.validation.test.js
+++ b/test/errors.validation.test.js
@@ -263,7 +263,6 @@ describe('ValidationError', function() {
     const Zeta = mongoose.model('Zeta', zetaSchema);
     const entry = new Zeta({ text: false, number: 'fsfsf' });
     entry.validate(function(error) {
-      console.log(JSON.parse(JSON.stringify(error)));
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.message)));
       assert.ok(JSON.parse(JSON.stringify(error.errors.number.name)));
     });

From df4b34054040a7456b7d09fff6ada61f8a0f37ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Nowak?= <michaln@qualtrics.com>
Date: Fri, 7 May 2021 11:34:36 +0200
Subject: [PATCH 2002/2348] fix: (index.d.ts) don't require error value in
 pre/post hooks

---
 index.d.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 50ba645b3fc..4159f5f2abd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1156,8 +1156,8 @@ declare module 'mongoose' {
     /** Defines a post hook for the model. */
     post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: (this: T, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err: CallbackError) => void) => void): this;
@@ -1165,8 +1165,8 @@ declare module 'mongoose' {
 
     post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Document = DocType>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: Array<any>, next: (err: CallbackError) => void) => void): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err: CallbackError) => void) => void): this;

From 5ec0526ee7517391ec10acd9059b4e49e30c18b3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 May 2021 14:26:19 -0400
Subject: [PATCH 2003/2348] test(populate): repro #10159

---
 test/model.populate.test.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index a2e9bbe8dbf..5bb4922765c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10358,7 +10358,26 @@ describe('model: populate:', function() {
       });
       assert.equal(res.administrators.length, 1);
       assert.equal(res.administrators[0].name, 'user1');
+    });
+  });
+
+  it('populates immutable array paths (gh-10159)', function() {
+    const Cat = db.model('Cat', {
+      name: String,
+      friends: [{
+        immutable: true,
+        type: mongoose.ObjectId,
+        ref: 'Cat'
+      }]
+    });
+
+    return co(function*() {
+      const friend = yield Cat.create({ name: 'Zildjian' });
+      const myCat = yield Cat.create({ name: 'Lord Fluffles', friends: [friend.id] });
+
+      yield myCat.populate('friends').execPopulate();
 
+      assert.equal(myCat.friends[0].name, 'Zildjian');
     });
   });
 });

From 10dfa8ac7ba5bc8150dc6870b0623d2bd1ff82b9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 May 2021 14:26:30 -0400
Subject: [PATCH 2004/2348] fix(populate): handle populating immutable array
 paths

Fix #10159
---
 lib/schema/array.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 88dea5a6241..f2e49e77c96 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -85,16 +85,16 @@ function SchemaArray(key, cast, options, schemaOptions) {
     if (typeof caster === 'function' &&
         !caster.$isArraySubdocument &&
         !caster.$isSchemaMap) {
-      this.caster = new caster(null, castOptions);
+      const path = this.caster instanceof EmbeddedDoc ? null : key;
+      this.caster = new caster(path, castOptions);
     } else {
       this.caster = caster;
+      if (!(this.caster instanceof EmbeddedDoc)) {
+        this.caster.path = key;
+      }
     }
 
     this.$embeddedSchemaType = this.caster;
-
-    if (!(this.caster instanceof EmbeddedDoc)) {
-      this.caster.path = key;
-    }
   }
 
   this.$isMongooseArray = true;

From c4ba0e97d4bbe938173c47ecb507010532b56a88 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 May 2021 15:07:33 -0400
Subject: [PATCH 2005/2348] fix(index.d.ts): separate `UpdateQuery` from
 `UpdateWithAggregationPipeline` for cases when `UpdateQuery` is used as a
 function param

Fix #10186
---
 index.d.ts | 48 ++++++++++++++++++++++++------------------------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4159f5f2abd..e02f864e004 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -586,10 +586,10 @@ declare module 'mongoose' {
     unmarkModified(path: string): void;
 
     /** Sends an update command with this document `_id` as the query selector. */
-    update(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
+    update(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
 
     /** Sends an updateOne command with this document `_id` as the query selector. */
-    updateOne(update?: UpdateQuery<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
+    updateOne(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
 
     /** Executes registered validation rules for this document. */
     validate(pathsToValidate?: Array<string>, options?: any): Promise<void>;
@@ -820,10 +820,10 @@ declare module 'mongoose' {
     findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T>, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
@@ -836,9 +836,9 @@ declare module 'mongoose' {
     findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<T>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<T>, T, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: T, res: any) => void): QueryWithHelpers<T, T, TQueryHelpers>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<T | null, T, TQueryHelpers>;
 
     geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<T>) => void): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
 
@@ -860,13 +860,13 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, T, TQueryHelpers>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): QueryWithHelpers<Array<T>, T, TQueryHelpers>;
@@ -1995,17 +1995,17 @@ declare module 'mongoose' {
     findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
-    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
+    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
 
     /** Specifies a `$geometry` condition */
     geometry(object: { type: string, coordinates: any[] }): this;
@@ -2030,7 +2030,7 @@ declare module 'mongoose' {
     getQuery(): FilterQuery<DocType>;
 
     /** Returns the current update operations as a JSON object. */
-    getUpdate(): UpdateQuery<DocType> | null;
+    getUpdate(): UpdateQuery<DocType> | UpdateWithAggregationPipeline | null;
 
     /** Specifies a `$gt` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     gt(val: number): this;
@@ -2192,7 +2192,7 @@ declare module 'mongoose' {
     /** Sets the query conditions to the provided JSON object. */
     setQuery(val: FilterQuery<DocType> | null): void;
 
-    setUpdate(update: UpdateQuery<DocType>): void;
+    setUpdate(update: UpdateQuery<DocType> | UpdateWithAggregationPipeline): void;
 
     /** Specifies an `$size` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     size(val: number): this;
@@ -2227,7 +2227,7 @@ declare module 'mongoose' {
     toConstructor(): new (...args: any[]) => QueryWithHelpers<ResultType, DocType, THelpers>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -2235,13 +2235,13 @@ declare module 'mongoose' {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
@@ -2329,7 +2329,7 @@ declare module 'mongoose' {
     { $replaceRoot: any } |
     { $replaceWith: any };
 
-  export type UpdateQuery<T> = (_UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>) | UpdateWithAggregationPipeline;
+  export type UpdateQuery<T> = (_UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>);
 
   type _AllowStringsForIds<T> = {
     [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;

From cb3fdc45675d01db87aaba46b82302d1ddf527fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 May 2021 21:14:51 -0400
Subject: [PATCH 2006/2348] test(populate): repro #10191

---
 test/model.populate.test.js | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 5bb4922765c..82d9ef4ad9d 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10380,4 +10380,39 @@ describe('model: populate:', function() {
       assert.equal(myCat.friends[0].name, 'Zildjian');
     });
   });
+
+  it('populates paths under mixed schematypes where some documents have non-object properties (gh-10191)', function() {
+    const schema = mongoose.Schema({
+      name: String,
+      params: [{
+        key: String,
+        value: 'Mixed'
+      }]
+    });
+    const Test = db.model('Test', schema);
+    const User = db.model('User', mongoose.Schema({ name: String }));
+
+    return co(function*() {
+      const user = yield User.create({ name: 'test' });
+
+      yield Test.create([
+        { name: 'test1', params: [{ key: 'textContext', value: 'asd' }] },
+        { name: 'test2', params: [{ key: 'logic', value: { optionLabels: [user._id] } }] }
+      ]);
+
+      const res = yield Test.find().sort({ name: 1 }).populate({
+        path: 'params.value.optionLabels',
+        model: User
+      });
+
+      assert.equal(res[0].name, 'test1');
+      assert.equal(res[0].params.length, 1);
+      assert.equal(res[0].params[0].value, 'asd');
+
+      assert.equal(res[1].name, 'test2');
+      assert.equal(res[1].params.length, 1);
+      assert.equal(res[1].params[0].value.optionLabels.length, 1);
+      assert.equal(res[1].params[0].value.optionLabels[0].name, 'test');
+    });
+  });
 });

From 97145d51b9da5e9fb84c7f57e9b34af97e0845b8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 8 May 2021 21:15:03 -0400
Subject: [PATCH 2007/2348] fix(populate): allow populating paths under mixed
 schematypes where some documents have non-object properties

Fix #10191
---
 lib/helpers/populate/lookupLocalFields.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/helpers/populate/lookupLocalFields.js b/lib/helpers/populate/lookupLocalFields.js
index fd925419b56..7fcfae561c6 100644
--- a/lib/helpers/populate/lookupLocalFields.js
+++ b/lib/helpers/populate/lookupLocalFields.js
@@ -10,6 +10,9 @@ module.exports = function lookupLocalFields(cur, path, val) {
   }
 
   if (arguments.length >= 3) {
+    if (typeof cur !== 'object') {
+      return void 0;
+    }
     cur[path] = val;
     return val;
   }

From 909cc875c77f9a84e4b63993e2e89d2a07af395c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 11:07:23 -0400
Subject: [PATCH 2008/2348] docs(deprecations): add note that you can safely
 ignore `useFindAndModify` and `useCreateIndex` deprecation warnings

Fix #10155
---
 docs/deprecations.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docs/deprecations.pug b/docs/deprecations.pug
index 2531d3f7bd3..784219ec113 100644
--- a/docs/deprecations.pug
+++ b/docs/deprecations.pug
@@ -117,6 +117,9 @@ block content
     * [`Query.findOneAndRemove()`](/docs/api.html#query_Query-findOneAndRemove)
     * [`Query.findOneAndUpdate()`](/docs/api.html#query_Query-findOneAndUpdate)
 
+    You can also safely ignore this warning. Mongoose will not remove the legacy `useFindAndModify: true`
+    behavior until Mongoose 6.0.
+
     <h2 id="ensureindex"><a href="#ensureindex"><code>ensureIndex()</code></a></h2>
 
     If you define [indexes in your Mongoose schemas](https://mongoosejs.com/docs/guide.html#indexes), you'll see the below
@@ -145,6 +148,9 @@ block content
     this option on without any code changes. If you discover any issues,
     please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
 
+    You can also safely ignore this warning. Mongoose will not remove the legacy `useCreateIndex: false`
+    behavior until Mongoose 6.0.
+
     <h2 id="remove"><a href="#remove"><code>remove()</code></a></h2>
 
     The MongoDB driver's [`remove()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove) is deprecated in favor of `deleteOne()` and `deleteMany()`. This is to comply with

From d65070ea95ff4956df027aec9d38d6effda51763 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 11:55:36 -0400
Subject: [PATCH 2009/2348] fix(query): add `allowDiskUse()` method to improve
 setting MongoDB 4.4's new `allowDiskUse` option

Fix #10177
---
 lib/query.js | 43 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 38 insertions(+), 5 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 46f8cce76d1..333faf00f3b 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1349,12 +1349,13 @@ Query.prototype.getOptions = function() {
  * - [sort](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsort(\)%7D%7D)
  * - [limit](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Blimit%28%29%7D%7D)
  * - [skip](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bskip%28%29%7D%7D)
- * - [maxscan](https://docs.mongodb.org/v3.2/reference/operator/meta/maxScan/#metaOp._S_maxScan)
+ * - [allowDiskUse](https://docs.mongodb.com/manual/reference/method/cursor.allowDiskUse/)
  * - [batchSize](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7BbatchSize%28%29%7D%7D)
- * - [comment](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24comment)
- * - [snapshot](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsnapshot%28%29%7D%7D)
  * - [readPreference](http://docs.mongodb.org/manual/applications/replication/#read-preference)
  * - [hint](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24hint)
+ * - [comment](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24comment)
+ * - [snapshot](http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsnapshot%28%29%7D%7D)
+ * - [maxscan](https://docs.mongodb.org/v3.2/reference/operator/meta/maxScan/#metaOp._S_maxScan)
  *
  * The following options are only for write operations: `update()`, `updateOne()`, `updateMany()`, `replaceOne()`, `findOneAndUpdate()`, and `findByIdAndUpdate()`:
  *
@@ -1445,7 +1446,7 @@ Query.prototype.setOptions = function(options, overwrite) {
  * query result. This method is useful for determining what index your queries
  * use.
  *
- * Calling `query.explain(v)` is equivalent to `query.setOption({ explain: v })`
+ * Calling `query.explain(v)` is equivalent to `query.setOptions({ explain: v })`
  *
  * ####Example:
  *
@@ -1469,12 +1470,44 @@ Query.prototype.explain = function(verbose) {
   return this;
 };
 
+/**
+ * Sets the [`allowDiskUse` option](https://docs.mongodb.com/manual/reference/method/cursor.allowDiskUse/),
+ * which allows the MongoDB server to use more than 100 MB for this query's `sort()`. This option can
+ * let you work around `QueryExceededMemoryLimitNoDiskUseAllowed` errors from the MongoDB server.
+ *
+ * Note that this option requires MongoDB server >= 4.4. Setting this option is a no-op for MongoDB 4.2
+ * and earlier.
+ *
+ * Calling `query.allowDiskUse(v)` is equivalent to `query.setOptions({ allowDiskUse: v })`
+ *
+ * ####Example:
+ *
+ *     await query.find().sort({ name: 1 }).allowDiskUse(true);
+ *     // Equivalent:
+ *     await query.find().sort({ name: 1 }).allowDiskUse();
+ *
+ * @param {Boolean} [v] Enable/disable `allowDiskUse`. If called with 0 arguments, sets `allowDiskUse: true`
+ * @return {Query} this
+ * @api public
+ */
+
+Query.prototype.allowDiskUse = function(v) {
+  if (arguments.length === 0) {
+    this.options.allowDiskUse = true;
+  } else if (v === false) {
+    delete this.options.allowDiskUse;
+  } else {
+    this.options.allowDiskUse = v;
+  }
+  return this;
+};
+
 /**
  * Sets the [maxTimeMS](https://docs.mongodb.com/manual/reference/method/cursor.maxTimeMS/)
  * option. This will tell the MongoDB server to abort if the query or write op
  * has been running for more than `ms` milliseconds.
  *
- * Calling `query.maxTimeMS(v)` is equivalent to `query.setOption({ maxTimeMS: v })`
+ * Calling `query.maxTimeMS(v)` is equivalent to `query.setOptions({ maxTimeMS: v })`
  *
  * ####Example:
  *

From 9726a81f2b820bf4b07a7a1b7a892bb43da21ac8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 13:00:57 -0400
Subject: [PATCH 2010/2348] docs(typescript): add a typescript intro tutorial
 and statics tutorial

Re: #10021
---
 docs/layout.pug            |   5 ++
 docs/source/index.js       |   1 +
 docs/typescript.pug        | 101 +++++++++++++++++++++++++++++++++++++
 docs/typescript/index.js   |  14 +++++
 docs/typescript/statics.md |  25 +++++++++
 website.js                 |   2 +-
 6 files changed, 147 insertions(+), 1 deletion(-)
 create mode 100644 docs/typescript.pug
 create mode 100644 docs/typescript/index.js
 create mode 100644 docs/typescript/statics.md

diff --git a/docs/layout.pug b/docs/layout.pug
index 52889b0b849..9d1f8fb3b15 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -99,6 +99,11 @@ html(lang='en')
                 a.pure-menu-link(href="/docs/plugins.html", class=outputUrl === '/docs/plugins.html' ? 'selected' : '') Plugins
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/transactions.html", class=outputUrl === '/docs/transactions.html' ? 'selected' : '') Transactions
+              li.pure-menu-item.sub-item
+                a.pure-menu-link(href="/docs/typescript.html", class=outputUrl === '/docs/typescript.html' ? 'selected' : '') TypeScript
+              - if (outputUrl.startsWith('/docs/typescript'))
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/typescript/statics.html", class=outputUrl === '/docs/typescript/statics.html' ? 'selected' : '') Statics
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
               li.pure-menu-item.sub-item
diff --git a/docs/source/index.js b/docs/source/index.js
index 9a78297a33e..56b7a791e65 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -27,6 +27,7 @@ exports['docs/deprecations.pug'] = { guide: true, title: 'Deprecation Warnings'
 exports['docs/further_reading.pug'] = { title: 'Further Reading' };
 exports['docs/jest.pug'] = { title: 'Testing Mongoose with Jest' };
 exports['docs/faq.pug'] = { guide: true, title: 'FAQ' };
+exports['docs/typescript.pug'] = { guide: true, title: 'Using TypeScript with Mongoose' };
 exports['docs/compatibility.pug'] = {
   title: 'MongoDB Version Compatibility',
   guide: true
diff --git a/docs/typescript.pug b/docs/typescript.pug
new file mode 100644
index 00000000000..a8f6cd2866c
--- /dev/null
+++ b/docs/typescript.pug
@@ -0,0 +1,101 @@
+extends layout
+
+block content
+  <a class="edit-docs-link" href="#{editLink}" target="_blank">
+    <img src="/docs/images/pencil.svg" />
+  </a>
+
+  :markdown
+    ## TypeScript Support
+
+    Mongoose introduced [officially supported TypeScript bindings in v5.11.0](https://thecodebarbarian.com/working-with-mongoose-in-typescript.html).
+    Mongoose's `index.d.ts` file supports a wide variety of syntaxes and strives to be compatible with `@types/mongoose` where possible.
+    This guide describes Mongoose's recommended approach to working with Mongoose in TypeScript.
+
+    ### Creating Your First Document
+
+    To get started with Mongoose in TypeScript, you need to: 
+
+    1. Create an interface representing a document in MongoDB.
+    2. Create a [Schema](/docs/guide.html) corresponding to the document interface.
+    3. Create a Model.
+    4. [Connect to MongoDB](/docs/connections.html).
+
+    ```typescript
+    import { Schema, model, connect } from 'mongoose';
+
+    // 1. Create an interface representing a document in MongoDB.
+    interface User {
+      name: string;
+      email: string;
+      avatar?: string;
+    }
+
+    // 2. Create a Schema corresponding to the document interface.
+    const schema = new Schema<User>({
+      name: { type: String, required: true },
+      email: { type: String, required: true },
+      avatar: String
+    });
+
+    // 3. Create a Model.
+    const UserModel = model<User>('User', schema);
+
+    run().catch(err => console.log(err));
+
+    async function run(): Promise<void> {
+      // 4. Connect to MongoDB
+      await connect('mongodb://localhost:27017/test', {
+        useNewUrlParser: true,
+        useUnifiedTopology: true
+      });
+
+      const doc = new UserModel({
+        name: 'Bill',
+        email: 'bill@initech.com',
+        avatar: 'https://i.imgur.com/dM7Thhn.png'
+      });
+      await doc.save();
+
+      console.log(doc.email); // 'bill@initech.com'
+    }
+    ```
+
+    You as the developer are responsible for ensuring that your document interface lines up with your Mongoose schema.
+    For example, Mongoose won't report an error if `email` is `required` in your Mongoose schema but optional in your document interface.
+
+    ### Using `extends Document`
+
+    Alternatively, your document interface can extend Mongoose's `Document` class.
+    Many Mongoose TypeScript codebases use the below approach.
+
+    ```typescript
+    import { Document, Schema, model, connect } from 'mongoose';
+
+    interface User extends Document {
+      name: string;
+      email: string;
+      avatar?: string;
+    }
+    ```
+
+    This approach works, but we recommend your document interface _not_ extend `Document`.
+    Using `extends Document` makes it difficult for Mongoose to infer which properties are present on [query filters](/docs/queries.html), [lean documents](/docs/tutorials/lean.html), and other cases.
+
+    We recommend your document interface contain the properties defined in your schema and line up with what your documents look like in MongoDB.
+    Although you can add [instance methods](/docs/guide.html#methods) to your document interface, we do not recommend doing so.
+
+    ### Using Custom Bindings
+
+    If Mongoose's built-in `index.d.ts` file does not work for you, you can remove it in a postinstall script in your `package.json` as shown below.
+    However, before you do, please [open an issue on Mongoose's GitHub page](https://github.com/Automattic/mongoose/issues/new) and describe the issue you're experiencing.
+
+    ```
+    {
+      "postinstall": "rm ./node_modules/mongoose/index.d.ts"
+    }
+    ```
+
+    ### Next Up
+
+    Now that you've seen the basics of how to use Mongoose in TypeScript, let's take a look at [statics in TypeScript](/docs/typescript/statics.html).
diff --git a/docs/typescript/index.js b/docs/typescript/index.js
new file mode 100644
index 00000000000..3d56082dde5
--- /dev/null
+++ b/docs/typescript/index.js
@@ -0,0 +1,14 @@
+'use strict';
+
+const fs = require('fs');
+
+const tutorials = fs.readdirSync(__dirname).filter(file => file.endsWith('.md'));
+
+module.exports = tutorials.reduce((map, filename) => {
+  const content = fs.readFileSync(`${__dirname}/${filename}`, 'utf8');
+  map[`docs/typescript/${filename}`] = {
+    title: `Mongoose: ${content.split('\n')[0].replace(/^#+/, '').trim()}`,
+    markdown: true
+  };
+  return map;
+}, {});
\ No newline at end of file
diff --git a/docs/typescript/statics.md b/docs/typescript/statics.md
new file mode 100644
index 00000000000..6685acb91b1
--- /dev/null
+++ b/docs/typescript/statics.md
@@ -0,0 +1,25 @@
+# Statics in TypeScript
+
+Mongoose [models](/docs/models.html) do **not** have an explicit generic parameter for [statics](/docs/guide.html#statics).
+If your model has statics, we recommend creating an interface that [extends](https://www.typescriptlang.org/docs/handbook/interfaces.html) Mongoose's `Model` interface as shown below.
+
+```typescript
+import { Model, Schema, model } from 'mongoose';
+
+interface IUser {
+  name: string;
+}
+
+interface UserModel extends Model<IUser> {
+  myStaticMethod(): number;
+}
+
+const schema = new Schema<IUser, UserModel>({ name: String });
+schema.static('myStaticMethod', function myStaticMethod() {
+  return 42;
+});
+
+const User = model<IUser, UserModel>('User', schema);
+
+const answer: number = User.myStaticMethod(); // 42
+```
\ No newline at end of file
diff --git a/website.js b/website.js
index 6687a41e802..f07c046dbfb 100644
--- a/website.js
+++ b/website.js
@@ -62,7 +62,7 @@ pkg.latest4x = getLatestLegacyVersion('4.');
 pkg.latest38x = getLatestLegacyVersion('3.8');
 
 require('./docs/splitApiDocs');
-const filemap = Object.assign({}, require('./docs/source'), require('./docs/tutorials'));
+const filemap = Object.assign({}, require('./docs/source'), require('./docs/tutorials'), require('./docs/typescript'));
 const files = Object.keys(filemap);
 
 const wrapMarkdown = md => `

From 7bedeb7db1a1a5813bad603b67e6ebd20aced0a7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 13:39:57 -0400
Subject: [PATCH 2011/2348] docs(typescript): add query helpers tutorial

Fix #10021
---
 docs/layout.pug                  |  2 ++
 docs/typescript/query-helpers.md | 61 ++++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+)
 create mode 100644 docs/typescript/query-helpers.md

diff --git a/docs/layout.pug b/docs/layout.pug
index 9d1f8fb3b15..fbf187b728d 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -104,6 +104,8 @@ html(lang='en')
               - if (outputUrl.startsWith('/docs/typescript'))
                 li.pure-menu-item.tertiary-item
                   a.pure-menu-link(href="/docs/typescript/statics.html", class=outputUrl === '/docs/typescript/statics.html' ? 'selected' : '') Statics
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/typescript/query-helpers.html", class=outputUrl === '/docs/typescript/query-helpers.html' ? 'selected' : '') Query Helpers
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
               li.pure-menu-item.sub-item
diff --git a/docs/typescript/query-helpers.md b/docs/typescript/query-helpers.md
new file mode 100644
index 00000000000..40f285f1e94
--- /dev/null
+++ b/docs/typescript/query-helpers.md
@@ -0,0 +1,61 @@
+# Query Helpers in TypeScript
+
+[Query helpers](http://thecodebarbarian.com/mongoose-custom-query-methods.html) let you define custom helper methods on Mongoose queries.
+Query helpers make queries more semantic using chaining syntax.
+
+```javascript
+ProjectSchema.query.byName = function(name) {
+  return this.find({ name: name });
+};
+var Project = mongoose.model('Project', ProjectSchema);
+
+// Works. Any Project query, whether it be `find()`, `findOne()`,
+// `findOneAndUpdate()`, `delete()`, etc. now has a `byName()` helper
+Project.find().where('stars').gt(1000).byName('mongoose');
+```
+
+In TypeScript, Mongoose's `Model` takes 3 generic parameters:
+
+1. The `DocType`
+2. a `TQueryHelpers` type
+3. a `TMethods` type
+
+The 2nd generic parameter, `TQueryHelpers`, should be an interface that contains a function signature for each of your query helpers.
+Below is an example of creating a `ProjectModel` with a `byName` query helper.
+
+```typescript
+import { Document, Model, Query, Schema, connect, model } from 'mongoose';
+
+interface Project {
+  name: string;
+  stars: number;
+}
+
+const schema = new Schema<Project>({
+  name: { type: String, required: true },
+  stars: { type: Number, required: true }
+});
+// Query helpers should return `Query<any, Document<DocType>> & ProjectQueryHelpers`
+// to enable chaining.
+interface ProjectQueryHelpers {
+  byName(name: string): Query<any, Document<Project>> & ProjectQueryHelpers;
+}
+schema.query.byName = function(name): Query<any, Document<Project>> & ProjectQueryHelpers {
+  return this.find({ name: name });
+};
+
+// 2nd param to `model()` is the Model class to return.
+const ProjectModel = model<Project, Model<Project, ProjectQueryHelpers>>('Project', schema);
+
+run().catch(err => console.log(err));
+
+async function run(): Promise<void> {
+  await connect('mongodb://localhost:27017/test', {
+    useNewUrlParser: true,
+    useUnifiedTopology: true
+  });
+  
+  // Equivalent to `ProjectModel.find({ stars: { $gt: 1000 }, name: 'mongoose' })`
+  await ProjectModel.find().where('stars').gt(1000).byName('mongoose');
+}
+```
\ No newline at end of file

From a116b62191dd77f7c919b8276191f138b5d62416 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 14:12:23 -0400
Subject: [PATCH 2012/2348] chore: release 5.12.8

---
 History.md   | 16 ++++++++++++++++
 package.json |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 15bdf208ddd..eff4a3e8888 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,19 @@
+5.12.8 / 2021-05-10
+===================
+ * fix(populate): handle populating immutable array paths #10159
+ * fix(CastError): add `toJSON()` function to ensure `name` property always ends up in `JSON.stringify()` output #10166 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(query): add allowDiskUse() method to improve setting MongoDB 4.4's new `allowDiskUse` option #10177
+ * fix(populate): allow populating paths under mixed schematypes where some documents have non-object properties #10191
+ * chore: remove unnecessary driver dynamic imports so Mongoose can work with Parcel #9603
+ * fix(index.d.ts): allow any object as parameter to create() and `insertMany()` #10144
+ * fix(index.d.ts): allow creating Model class with raw interface, no `extends Document` #10144
+ * fix(index.d.ts): separate UpdateQuery from `UpdateWithAggregationPipeline` for cases when `UpdateQuery` is used as a function param #10186
+ * fix(index.d.ts): don't require error value in pre/post hooks #10213 [michaln-q](https://github.com/michaln-q)
+ * docs(typescript): add a typescript intro tutorial and statics tutorial #10021
+ * docs(typescript): add query helpers tutorial #10021
+ * docs(deprecations): add note that you can safely ignore `useFindAndModify` and `useCreateIndex` deprecation warnings #10155
+ * chore(workflows): add node 16 to github actions #10201 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+
 5.12.7 / 2021-04-29
 ===================
  * fix(document): make $getPopulatedDocs() return populated virtuals #10148
diff --git a/package.json b/package.json
index 3fadc9860f2..6039f8cb5c4 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.7",
+  "version": "5.12.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 45bc433fb4a237a4bacd650067ff8a06e7afac7d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 20:47:20 -0400
Subject: [PATCH 2013/2348] fix(index.d.ts): allow returning `Promise<void>`
 from middleware functions

Fix #10229
---
 index.d.ts                    | 54 +++++++++++++++++++----------------
 test/typescript/middleware.ts |  3 +-
 2 files changed, 31 insertions(+), 26 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 2e87eab0bce..8d89aa10921 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1082,6 +1082,10 @@ declare module 'mongoose' {
   type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
+  type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
+  type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
+  type ErrorHandlingMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, err: NativeError, res: ResType, next: (err?: CallbackError) => void) => void;
+
   class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
     /**
      * Create a new schema
@@ -1156,33 +1160,33 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema<DocType, Model<DocType>, SchemaDefinitionType>, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, res: Array<any>, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: (this: T, res: Array<any>, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, res: any, next: (err?: CallbackError) => void) => void): this;
-
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next?: (err: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, err: NativeError, res: Array<any>, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: Array<any>, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: (this: T, err: NativeError, res: any, next: (err?: CallbackError) => void) => void): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PostMiddlewareFunction<T>): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: PostMiddlewareFunction<T>): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: PostMiddlewareFunction<T, Array<any>>): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T, Array<any>>): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: PostMiddlewareFunction<T>): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
+
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
+    post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
 
     /** Defines a pre hook for the model. */
-    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
-    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void) => void): this;
-    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err: CallbackError) => void) => void): this;
-    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void): this;
-    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void): this;
+    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PreMiddlewareFunction<T>): this;
+    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: PreMiddlewareFunction<T>): this;
+    pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: PreMiddlewareFunction<T>): this;
+    pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
+    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
+    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
 
     /** Object of currently defined query helpers on this schema. */
     query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index 45ca4c901dd..e82ec14c54f 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -40,7 +40,8 @@ schema.post<ITest>('save', function(err: Error, res: ITest, next: Function) {
 });
 
 schema.pre<Model<ITest>>('insertMany', function() {
-  return Promise.resolve(this.name);
+  const name: string = this.name;
+  return Promise.resolve();
 });
 
 schema.pre<Model<ITest>>('insertMany', { document: false, query: false }, function() {

From fa9ad9670de76156da5a6dff16288404ad7d2f84 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 21:37:06 -0400
Subject: [PATCH 2014/2348] fix(document): allow calling `validate()` and
 `validateSync()` with `options` as first parameter

Re: #10216
---
 lib/document.js       | 17 ++++++++++++++++-
 test/document.test.js |  4 ++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 9fb65857669..260a80e3c34 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2228,7 +2228,17 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
     this.$__.validating = new ParallelValidateError(this, { parentStack: options && options.parentStack });
   }
 
-  if (typeof pathsToValidate === 'function') {
+  if (arguments.length === 1) {
+    if (typeof arguments[0] === 'object' && !Array.isArray(arguments[0])) {
+      options = arguments[0];
+      callback = null;
+      pathsToValidate = null;
+    } else if (typeof arguments[0] === 'function') {
+      callback = arguments[0];
+      options = null;
+      pathsToValidate = null;
+    }
+  } else if (typeof pathsToValidate === 'function') {
     callback = pathsToValidate;
     options = null;
     pathsToValidate = null;
@@ -2599,6 +2609,11 @@ function _handlePathsToValidate(paths, pathsToValidate) {
 Document.prototype.validateSync = function(pathsToValidate, options) {
   const _this = this;
 
+  if (arguments.length === 1 && typeof arguments[0] === 'object' && !Array.isArray(arguments[0])) {
+    options = arguments[0];
+    pathsToValidate = null;
+  }
+
   const hasValidateModifiedOnlyOption = options &&
       (typeof options === 'object') &&
       ('validateModifiedOnly' in options);
diff --git a/test/document.test.js b/test/document.test.js
index 4221a972ccc..9be6f4025d6 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2534,7 +2534,7 @@ describe('document', function() {
         const doc = docs[0];
         doc.other = 'something';
         doc.subdocs[1].name = 'test2';
-        assert.equal(doc.validateSync(undefined, { validateModifiedOnly: true }), null);
+        assert.equal(doc.validateSync({ validateModifiedOnly: true }), null);
         doc.save({ validateModifiedOnly: true }, function(error) {
           assert.equal(error, null);
           done();
@@ -2551,7 +2551,7 @@ describe('document', function() {
         assert.equal(createError, null);
         const doc = docs[0];
         doc.title = '';
-        assert.ok(doc.validateSync(undefined, { validateModifiedOnly: true }).errors);
+        assert.ok(doc.validateSync({ validateModifiedOnly: true }).errors);
         doc.save({ validateModifiedOnly: true }, function(error) {
           assert.ok(error.errors);
           done();

From 3dda1669e36a3ea0f38f472bf6d1427b5aea3c09 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 21:54:35 -0400
Subject: [PATCH 2015/2348] test(schema): repro #10193

---
 test/schema.test.js | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index fd611e0dc62..29f678c23ec 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2608,4 +2608,19 @@ describe('schema', function() {
     assert.equal(schema.path('field1.field2').instance, 'Embedded');
     assert.equal(schema.path('field1.field2.field3').instance, 'Boolean');
   });
+
+  it('supports creating nested paths underneath document arrays (gh-10193)', function() {
+    const DynamicTextMatchFeaturesSchema = new Schema({ css: { color: String } });
+
+    const ElementSchema = new Schema({
+      image: { type: String },
+      possibleElements: [{
+        textMatchFeatures: {
+          dynamic: DynamicTextMatchFeaturesSchema
+        }
+      }]
+    });
+
+    assert.ok(ElementSchema.path('possibleElements').schema.path('textMatchFeatures.dynamic').schema.nested['css']);
+  });
 });

From 060a46c1d89f6a4065949813489984285cbea82d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 10 May 2021 21:54:47 -0400
Subject: [PATCH 2016/2348] fix(schema): support creating nested paths
 underneath document arrays

Fix #10193
---
 lib/schema.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 5e69f026bc9..0131e4b21c9 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -778,8 +778,11 @@ Schema.prototype.path = function(path, obj) {
       schemaType.schema.subpaths[key].$isUnderneathDocArray = true;
     }
     for (const key of Object.keys(schemaType.schema.singleNestedPaths)) {
-      this.subpaths[path + '.' + key] = schemaType.schema.singleNestedPaths[key];
-      schemaType.schema.singleNestedPaths[key].$isUnderneathDocArray = true;
+      const _schemaType = schemaType.schema.singleNestedPaths[key];
+      this.subpaths[path + '.' + key] = _schemaType;
+      if (typeof _schemaType === 'object' && _schemaType != null) {
+        _schemaType.$isUnderneathDocArray = true;
+      }
     }
   }
 

From a3c9acd12d00d396c92f8a7bb81fe3cfa3331e57 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 May 2021 09:17:13 -0400
Subject: [PATCH 2017/2348] fix(schema): apply static properties to model when
 using `loadClass()`

Fix #10206
---
 lib/schema.js | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 0131e4b21c9..a68517afb49 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1909,13 +1909,11 @@ Schema.prototype.loadClass = function(model, virtualsOnly) {
   // Add static methods
   if (!virtualsOnly) {
     Object.getOwnPropertyNames(model).forEach(function(name) {
-      if (name.match(/^(length|name|prototype)$/)) {
+      if (name.match(/^(length|name|prototype|constructor|__proto__)$/)) {
         return;
       }
-      const method = Object.getOwnPropertyDescriptor(model, name);
-      if (typeof method.value === 'function') {
-        this.static(name, method.value);
-      }
+      const prop = Object.getOwnPropertyDescriptor(model, name);
+      this.static(name, prop.value);
     }, this);
   }
 

From 1fa1105e9fd55ace64ad74cce98119fc3f28dcb6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 May 2021 13:33:59 -0400
Subject: [PATCH 2018/2348] test(schema): repro #10203

---
 test/schema.test.js | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 29f678c23ec..98812663d26 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1309,6 +1309,31 @@ describe('schema', function() {
 
       done();
     });
+
+    it('overwrites existing paths (gh-10203)', function() {
+      const baseSchema = new Schema({
+        username: {
+          type: String,
+          required: false
+        }
+      });
+    
+      const userSchema = new Schema({
+        email: {
+          type: String,
+          required: true
+        },
+        username: {
+          type: String,
+          required: true
+        }
+      });
+    
+      const realSchema = baseSchema.clone();
+      realSchema.add(userSchema);
+
+      assert.ok(realSchema.path('username').isRequired);
+    });
   });
 
   it('debugging msgs', function(done) {

From 358fdb00384fac94b19a6741a3e715080835d01f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 May 2021 13:34:28 -0400
Subject: [PATCH 2019/2348] fix(schema): ensure `add()` overwrites existing
 schema paths by default

Fix #10203
---
 lib/helpers/schema/merge.js | 4 ++--
 lib/utils.js                | 3 ++-
 test/schema.test.js         | 4 ++--
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/lib/helpers/schema/merge.js b/lib/helpers/schema/merge.js
index b1f16356fcc..edc5175eedc 100644
--- a/lib/helpers/schema/merge.js
+++ b/lib/helpers/schema/merge.js
@@ -1,10 +1,10 @@
 'use strict';
 
-module.exports = function merge(s1, s2) {
+module.exports = function merge(s1, s2, skipConflictingPaths) {
   const paths = Object.keys(s2.tree);
   const pathsToAdd = {};
   for (const key of paths) {
-    if (s1.paths[key] || s1.nested[key] || s1.singleNestedPaths[key]) {
+    if (skipConflictingPaths && (s1.paths[key] || s1.nested[key] || s1.singleNestedPaths[key])) {
       continue;
     }
     pathsToAdd[key] = s2.tree[key];
diff --git a/lib/utils.js b/lib/utils.js
index 7966c332a3b..fd381fc20c9 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -17,6 +17,7 @@ const isBsonType = require('./helpers/isBsonType');
 const getFunctionName = require('./helpers/getFunctionName');
 const isMongooseObject = require('./helpers/isMongooseObject');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
+const schemaMerge = require('./helpers/schema/merge');
 const specialProperties = require('./helpers/specialProperties');
 
 let Document;
@@ -282,7 +283,7 @@ exports.merge = function merge(to, from, options, path) {
           continue;
         } else if (from[key].instanceOfSchema) {
           if (to[key].instanceOfSchema) {
-            to[key].add(from[key].clone());
+            schemaMerge(to[key], from[key].clone(), options.isDiscriminatorSchemaMerge);
           } else {
             to[key] = from[key].clone();
           }
diff --git a/test/schema.test.js b/test/schema.test.js
index 98812663d26..722bc73b0ec 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -1317,7 +1317,7 @@ describe('schema', function() {
           required: false
         }
       });
-    
+
       const userSchema = new Schema({
         email: {
           type: String,
@@ -1328,7 +1328,7 @@ describe('schema', function() {
           required: true
         }
       });
-    
+
       const realSchema = baseSchema.clone();
       realSchema.add(userSchema);
 

From 05ebceadf45fd74872295faad1a5dae07eec9299 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 11 May 2021 22:08:31 -0400
Subject: [PATCH 2020/2348] fix(index.d.ts): add pre('distinct') hooks to
 TypeScript

Fix #10192
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 8d89aa10921..342e1fa052b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1074,7 +1074,7 @@ declare module 'mongoose' {
   }
 
   type MongooseDocumentMiddleware = 'validate' | 'save' | 'remove' | 'updateOne' | 'deleteOne' | 'init';
-  type MongooseQueryMiddleware = 'count' | 'deleteMany' | 'deleteOne' | 'find' | 'findOne' | 'findOneAndDelete' | 'findOneAndRemove' | 'findOneAndUpdate' | 'remove' | 'update' | 'updateOne' | 'updateMany';
+  type MongooseQueryMiddleware = 'count' | 'deleteMany' | 'deleteOne' | 'distinct' | 'find' | 'findOne' | 'findOneAndDelete' | 'findOneAndRemove' | 'findOneAndUpdate' | 'remove' | 'update' | 'updateOne' | 'updateMany';
 
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };

From 79928e592a7be0d10d5fc9b87541e5d08f94a4ea Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 12 May 2021 16:43:14 -0400
Subject: [PATCH 2021/2348] added onlyVirtuals to loadClass

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 342e1fa052b..86ed4a274c3 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1131,7 +1131,7 @@ declare module 'mongoose' {
      * [methods](http://mongoosejs.com/docs/guide.html#methods).
      */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    loadClass(model: Function): this;
+    loadClass(model: Function, onlyVirtuals: boolean): this;
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types

From 6f42360394c84888dc9da404044227be04cf2f36 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 12 May 2021 18:07:43 -0400
Subject: [PATCH 2022/2348] added test and tracked where to start

---
 lib/model.js       |  2 +-
 lib/query.js       |  4 ++--
 test/model.test.js | 14 ++++++++++++++
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 3bb4f38ede7..1a2922533bd 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2171,6 +2171,7 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
   mq.select(projection);
 
   mq.setOptions(options);
+
   if (this.schema.discriminatorMapping &&
       this.schema.discriminatorMapping.isRoot &&
       mq.selectedInclusively()) {
@@ -2178,7 +2179,6 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
   }
 
   callback = this.$handleCallbackError(callback);
-
   return mq.findOne(conditions, callback);
 };
 
diff --git a/lib/query.js b/lib/query.js
index 333faf00f3b..20605ae3468 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1393,6 +1393,8 @@ Query.prototype.getOptions = function() {
  */
 
 Query.prototype.setOptions = function(options, overwrite) {
+  // work here
+  console.log(options);
   // overwrite is only for internal use
   if (overwrite) {
     // ensure that _mongooseOptions & options are two different objects
@@ -2265,7 +2267,6 @@ Query.prototype._findOne = wrapThunk(function(callback) {
 
 Query.prototype.findOne = function(conditions, projection, options, callback) {
   this.op = 'findOne';
-
   if (typeof conditions === 'function') {
     callback = conditions;
     conditions = null;
@@ -2305,7 +2306,6 @@ Query.prototype.findOne = function(conditions, projection, options, callback) {
   }
 
   this.exec(callback);
-
   return this;
 };
 
diff --git a/test/model.test.js b/test/model.test.js
index bde6cf2de16..b7aa7d5c393 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7203,4 +7203,18 @@ describe('Model', function() {
       }
     });
   });
+
+  it('supports skipping defaults on a find operation gh-7287', function() {
+    const betaSchema = new Schema({
+      name: { type: String, default: 'foo' },
+      age: { type: Number }
+    });
+
+    const Beta = db.model('Beta', betaSchema);
+    return co(function*() {
+      const doc = yield Beta.create({ age: 21 });
+      const test = yield Beta.findOne({ _id: doc.id }).setOptions({ defaults: false });
+      assert.ok(!test.name);
+    });
+  });
 });

From a3e05389b1e8dd6acd0b553f24d798b8b3a63e8a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 May 2021 13:35:14 -0400
Subject: [PATCH 2023/2348] fix(update): convert nested dotted paths in update
 to nested paths to avoid ending up with dotted properties in update

Fix #10200
---
 lib/helpers/path/setDottedPath.js | 16 ++++++
 lib/helpers/query/castUpdate.js   | 11 +++-
 test/model.update.test.js         | 94 +++++++++++++++++++++++++++++++
 3 files changed, 120 insertions(+), 1 deletion(-)
 create mode 100644 lib/helpers/path/setDottedPath.js

diff --git a/lib/helpers/path/setDottedPath.js b/lib/helpers/path/setDottedPath.js
new file mode 100644
index 00000000000..fe6b9b5afea
--- /dev/null
+++ b/lib/helpers/path/setDottedPath.js
@@ -0,0 +1,16 @@
+'use strict';
+
+module.exports = function setDottedPath(obj, path, val) {
+  const parts = path.split('.');
+  let cur = obj;
+  for (const part of parts.slice(0, -1)) {
+    if (cur[part] == null) {
+      cur[part] = {};
+    }
+
+    cur = cur[part];
+  }
+
+  const last = parts[parts.length - 1];
+  cur[last] = val;
+};
\ No newline at end of file
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index 29b16c9824d..b14efc30d49 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -10,6 +10,7 @@ const getEmbeddedDiscriminatorPath = require('./getEmbeddedDiscriminatorPath');
 const handleImmutable = require('./handleImmutable');
 const moveImmutableProperties = require('../update/moveImmutableProperties');
 const schemaMixedSymbol = require('../../schema/symbols').schemaMixedSymbol;
+const setDottedPath = require('../path/setDottedPath');
 const utils = require('../../utils');
 
 /*!
@@ -360,7 +361,15 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
         }
 
         try {
-          obj[key] = castUpdateVal(schematype, val, op, key, context, prefix + key);
+          if (prefix.length === 0 || key.indexOf('.') === -1) {
+            obj[key] = castUpdateVal(schematype, val, op, key, context, prefix + key);
+          } else {
+            // Setting a nested dotted path that's in the schema. We don't allow paths with '.' in
+            // a schema, so replace the dotted path with a nested object to avoid ending up with
+            // dotted properties in the updated object. See (gh-10200)
+            setDottedPath(obj, key, castUpdateVal(schematype, val, op, key, context, prefix + key));
+            delete obj[key];
+          }
         } catch (error) {
           aggregatedError = _handleCastError(error, context, key, aggregatedError);
         }
diff --git a/test/model.update.test.js b/test/model.update.test.js
index 5e3d7601a81..1c7a2d52ad2 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3578,4 +3578,98 @@ describe('model: updateOne: ', function() {
       assert.equal(fromDb.children[0].name, 'Luke Skywalker');
     });
   });
+
+  describe('converts dot separated paths to nested structure (gh-10200)', () => {
+    it('works with Model.updateOne(...)', () => { // fails in 5.12.7
+      return co(function*() {
+        const User = getPaymentModel();
+        const userPOJO = getPaymentWithDotSeparatedPaths();
+
+        const emptyUser = yield User.create({});
+        yield User.updateOne({ _id: emptyUser._id }, userPOJO);
+        const user = yield User.findOne({ _id: emptyUser._id }).lean();
+
+        assertDocumentStructure(user);
+      });
+    });
+    it('works with Model.bulkWrite(...)', () => { // fails in 5.12.7
+      return co(function*() {
+        const Payment = getPaymentModel();
+        const paymentPOJO = getPaymentWithDotSeparatedPaths();
+
+        const emptyPayment = yield Payment.create({});
+
+        yield Payment.bulkWrite([
+          { updateOne: { filter: { _id: emptyPayment._id }, update: paymentPOJO } }
+        ]);
+        const payment = yield Payment.findOne({ _id: emptyPayment._id }).lean();
+
+        assertDocumentStructure(payment);
+      });
+    });
+
+
+    function getPaymentModel() {
+      const paymentSchema = new Schema({
+        paymentFor: String,
+        externalServiceResponse: {
+          id: String,
+          resultDetails: {
+            clearingInstituteName: String,
+            transaction: {
+              receipt: String,
+              authorizationCode: String,
+              acquirer: { settlementDate: String }
+            },
+            response: { acquirerCode: String, acquirerMessage: String },
+            authorizationResponse: { stan: String },
+            sourceOfFunds: { provided: { card: { issuer: String } } }
+          }
+        }
+      });
+
+      const Payment = db.model('Payment', paymentSchema);
+      return Payment;
+    }
+
+    function getPaymentWithDotSeparatedPaths() {
+      return {
+        paymentFor: 'order',
+        externalServiceResponse: {
+          id: '1',
+          resultDetails: {
+            clearingInstituteName: 'Our local bank',
+            'authorizationResponse.stan': '123456',
+            'transaction.receipt': 'I am a transaction receipt',
+            'transaction.authorizationCode': 'ABCDEF',
+            'transaction.acquirer.settlementDate': 'February 2021',
+            'sourceOfFunds.provided.card.issuer': 'Big bank corporation',
+            nonExistentField: 'I should not be present'
+          }
+        }
+      };
+    }
+
+    function assertDocumentStructure(payment) {
+      assert.equal(payment.paymentFor, 'order');
+      assert.equal(payment.externalServiceResponse.id, '1');
+      assert.equal(payment.externalServiceResponse.resultDetails.clearingInstituteName, 'Our local bank');
+      assert.deepEqual(
+        payment.externalServiceResponse.resultDetails.authorizationResponse,
+        { stan: '123456' }
+      );
+      assert.deepEqual(
+        payment.externalServiceResponse.resultDetails.transaction,
+        {
+          receipt: 'I am a transaction receipt',
+          authorizationCode: 'ABCDEF',
+          acquirer: { settlementDate: 'February 2021' }
+        }
+      );
+      assert.deepEqual(
+        payment.externalServiceResponse.resultDetails.sourceOfFunds,
+        { provided: { card: { issuer: 'Big bank corporation' } } }
+      );
+    }
+  });
 });
\ No newline at end of file

From 7d564ebc98723e1acc8131ab2b25a6b8bd535578 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 May 2021 13:39:07 -0400
Subject: [PATCH 2024/2348] style: remove unnecessary comment

---
 test/model.update.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index 1c7a2d52ad2..e1be08022f0 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3580,7 +3580,7 @@ describe('model: updateOne: ', function() {
   });
 
   describe('converts dot separated paths to nested structure (gh-10200)', () => {
-    it('works with Model.updateOne(...)', () => { // fails in 5.12.7
+    it('works with Model.updateOne(...)', () => {
       return co(function*() {
         const User = getPaymentModel();
         const userPOJO = getPaymentWithDotSeparatedPaths();
@@ -3592,7 +3592,7 @@ describe('model: updateOne: ', function() {
         assertDocumentStructure(user);
       });
     });
-    it('works with Model.bulkWrite(...)', () => { // fails in 5.12.7
+    it('works with Model.bulkWrite(...)', () => {
       return co(function*() {
         const Payment = getPaymentModel();
         const paymentPOJO = getPaymentWithDotSeparatedPaths();

From 462963c186018a1d089c6c1ffad948d0b8997bb0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 May 2021 13:52:45 -0400
Subject: [PATCH 2025/2348] fix(query): re-enable using MongoDB 4.4 projection
 expressions

Fix #10188
Re: #10205
Re: #10142
---
 lib/query.js | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 333faf00f3b..3b988756431 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -963,10 +963,6 @@ Query.prototype.select = function select() {
     const keys = Object.keys(arg);
     for (let i = 0; i < keys.length; ++i) {
       let value = arg[keys[i]];
-      // Workaround for gh-10142
-      if (typeof value === 'string') {
-        value = 1;
-      }
       fields[keys[i]] = value;
       userProvidedFields[keys[i]] = value;
     }

From cacdf3b90acd1c5a82bacaefaadebe8d2be4684b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 May 2021 13:58:30 -0400
Subject: [PATCH 2026/2348] chore: address CR comments

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 86ed4a274c3..835b73b4f16 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1131,7 +1131,7 @@ declare module 'mongoose' {
      * [methods](http://mongoosejs.com/docs/guide.html#methods).
      */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    loadClass(model: Function, onlyVirtuals: boolean): this;
+    loadClass(model: Function, onlyVirtuals?: boolean): this;
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types

From fcd108adf8d7b28ca5620618e899c68336d95cf5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 13 May 2021 14:20:50 -0400
Subject: [PATCH 2027/2348] chore: release 5.12.9

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index eff4a3e8888..43d374089ab 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.12.9 / 2021-05-13
+===================
+ * fix(schema): ensure add() overwrites existing schema paths by default #10208 #10203
+ * fix(schema): support creating nested paths underneath document arrays #10193
+ * fix(update): convert nested dotted paths in update to nested paths to avoid ending up with dotted properties in update #10200
+ * fix(document): allow calling validate() and validateSync() with `options` as first parameter #10216
+ * fix(schema): apply static properties to model when using loadClass() #10206
+ * fix(index.d.ts): allow returning Promise<void> from middleware functions #10229
+ * fix(index.d.ts): add pre('distinct') hooks to TypeScript #10192
+
 5.12.8 / 2021-05-10
 ===================
  * fix(populate): handle populating immutable array paths #10159
diff --git a/package.json b/package.json
index 6039f8cb5c4..3f1a8d12f86 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.8",
+  "version": "5.12.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 083a488735e9b1b33efce8054e8ed593bbbedb7b Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 13 May 2021 18:02:34 -0400
Subject: [PATCH 2028/2348] better understanding of what to do and where to
 make changes

---
 lib/document.js     |  7 ++++++-
 lib/model.js        |  3 +--
 lib/query.js        | 13 ++++++++++---
 lib/queryhelpers.js |  4 +++-
 test/model.test.js  |  1 +
 5 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 260a80e3c34..f7aa890dc3e 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -70,6 +70,7 @@ const specialProperties = utils.specialProperties;
  */
 
 function Document(obj, fields, skipId, options) {
+  console.log('doc', new Error().stack)
   if (typeof skipId === 'object' && skipId != null) {
     options = skipId;
     skipId = options.skipId;
@@ -96,7 +97,7 @@ function Document(obj, fields, skipId, options) {
   this.$__.$options = options || {};
   this.$locals = {};
   this.$op = null;
-
+  console.log(this);
   if (obj != null && typeof obj !== 'object') {
     throw new ObjectParameterError(obj, 'obj', 'Document');
   }
@@ -136,6 +137,7 @@ function Document(obj, fields, skipId, options) {
     // By default, defaults get applied **before** setting initial values
     // Re: gh-6155
     if (defaults) {
+      console.log('z')
       $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, true, {
         isNew: this.isNew
       });
@@ -158,12 +160,14 @@ function Document(obj, fields, skipId, options) {
   // see the full doc rather than an empty one, unless they opt out.
   // Re: gh-3781, gh-6155
   if (options.willInit && defaults) {
+    console.log('a');
     EventEmitter.prototype.once.call(this, 'init', () => {
       $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
         isNew: this.isNew
       });
     });
   } else if (defaults) {
+    console.log('b');
     $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
       isNew: this.isNew
     });
@@ -344,6 +348,7 @@ function $__hasIncludedChildren(fields) {
  */
 
 function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isBeforeSetters, pathsToSkip) {
+  console.log('the values', doc,fields,skipId, exclude, hasIncludedChildren, isBeforeSetters, pathsToSkip);
   const paths = Object.keys(doc.$__schema.paths);
   const plen = paths.length;
 
diff --git a/lib/model.js b/lib/model.js
index 1a2922533bd..5bbfcf33658 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -2152,7 +2152,6 @@ Model.findById = function findById(id, projection, options, callback) {
 
 Model.findOne = function findOne(conditions, projection, options, callback) {
   _checkContext(this, 'findOne');
-
   if (typeof options === 'function') {
     callback = options;
     options = null;
@@ -2171,7 +2170,6 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
   mq.select(projection);
 
   mq.setOptions(options);
-
   if (this.schema.discriminatorMapping &&
       this.schema.discriminatorMapping.isRoot &&
       mq.selectedInclusively()) {
@@ -4675,6 +4673,7 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
   } else {
     // generate new class
     model = function model(doc, fields, skipId) {
+      console.log('this is the object being sent', skipId);
       model.hooks.execPreSync('createModel', doc);
       if (!(this instanceof model)) {
         return new model(doc, fields, skipId);
diff --git a/lib/query.js b/lib/query.js
index 20605ae3468..205ba1df94c 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1393,8 +1393,7 @@ Query.prototype.getOptions = function() {
  */
 
 Query.prototype.setOptions = function(options, overwrite) {
-  // work here
-  console.log(options);
+
   // overwrite is only for internal use
   if (overwrite) {
     // ensure that _mongooseOptions & options are two different objects
@@ -1439,6 +1438,13 @@ Query.prototype.setOptions = function(options, overwrite) {
     delete options.overwriteDiscriminatorKey;
   }
 
+  if ('defaults' in options) {
+    // console.log('this is options in setOptions', options);
+    // console.log(new Error().stack);
+    this._mongooseOptions.defaults = options.defaults;
+    // delete options.defaults;
+  }
+
   return Query.base.setOptions.call(this, options);
 };
 
@@ -2941,6 +2947,7 @@ Query.prototype._deleteMany = wrapThunk(function(callback) {
  */
 
 function completeOne(model, doc, res, options, fields, userProvidedFields, pop, callback) {
+  console.log(options);
   const opts = pop ?
     { populated: pop }
     : undefined;
@@ -2950,7 +2957,7 @@ function completeOne(model, doc, res, options, fields, userProvidedFields, pop,
     return null;
   }
 
-  const casted = helpers.createModel(model, doc, fields, userProvidedFields);
+  const casted = helpers.createModel(model, doc, fields, userProvidedFields,options);
   try {
     casted.init(doc, opts, _init);
   } catch (error) {
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index cf475a7e234..acf3a42340b 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -85,7 +85,9 @@ exports.preparePopulationOptionsMQ = function preparePopulationOptionsMQ(query,
  *
  * @return {Document}
  */
-exports.createModel = function createModel(model, doc, fields, userProvidedFields) {
+exports.createModel = function createModel(model, doc, fields, userProvidedFields, options) {
+  console.log('this is options in createModel', options)
+  console.log(new Error().stack);
   model.hooks.execPreSync('createModel', doc);
   const discriminatorMapping = model.schema ?
     model.schema.discriminatorMapping :
diff --git a/test/model.test.js b/test/model.test.js
index b7aa7d5c393..2d9a45ff5fb 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7214,6 +7214,7 @@ describe('Model', function() {
     return co(function*() {
       const doc = yield Beta.create({ age: 21 });
       const test = yield Beta.findOne({ _id: doc.id }).setOptions({ defaults: false });
+      console.log('this is from the test', test);
       assert.ok(!test.name);
     });
   });

From aaa0485c5274b903caf410cb0e4e84fc21917a02 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 May 2021 10:09:42 -0400
Subject: [PATCH 2029/2348] fix(CastError): add value type to cast error
 message

Fix #10207
---
 lib/error/cast.js                   | 39 +++++++++++++++++++++++++----
 test/docs/custom-casting.test.js    |  2 +-
 test/docs/schematypes.test.js       |  2 +-
 test/docs/validation.test.js        |  2 +-
 test/es-next/cast.test.es6.js       |  2 +-
 test/model.findOneAndUpdate.test.js |  2 +-
 test/model.querying.test.js         |  6 ++---
 test/schema.test.js                 |  2 +-
 test/schema.validation.test.js      |  4 +--
 test/types.buffer.test.js           |  2 +-
 10 files changed, 46 insertions(+), 17 deletions(-)

diff --git a/lib/error/cast.js b/lib/error/cast.js
index c41b703a572..794aadd761c 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -22,16 +22,27 @@ class CastError extends MongooseError {
     // If no args, assume we'll `init()` later.
     if (arguments.length > 0) {
       const stringValue = getStringValue(value);
+      const valueType = getValueType(value);
       const messageFormat = getMessageFormat(schemaType);
-      const msg = formatMessage(null, type, stringValue, path, messageFormat);
+      const msg = formatMessage(null, type, stringValue, path, messageFormat, valueType);
       super(msg);
       this.init(type, value, path, reason, schemaType);
     } else {
       super(formatMessage());
     }
   }
+
   toJSON() {
-    return { stringValue: this.stringValue, kind: this.kind, value: this.value, path: this.path, reason: this.reason, name: this.name, message: this.message };
+    return {
+      stringValue: this.stringValue,
+      valueType: this.valueType,
+      kind: this.kind,
+      value: this.value,
+      path: this.path,
+      reason: this.reason,
+      name: this.name,
+      message: this.message
+    };
   }
   /*!
    * ignore
@@ -43,6 +54,7 @@ class CastError extends MongooseError {
     this.value = value;
     this.path = path;
     this.reason = reason;
+    this.valueType = getValueType(value);
   }
 
   /*!
@@ -57,6 +69,7 @@ class CastError extends MongooseError {
     this.path = other.path;
     this.reason = other.reason;
     this.message = other.message;
+    this.valueType = other.valueType;
   }
 
   /*!
@@ -65,7 +78,7 @@ class CastError extends MongooseError {
   setModel(model) {
     this.model = model;
     this.message = formatMessage(model, this.kind, this.stringValue, this.path,
-      this.messageFormat);
+      this.messageFormat, this.valueType);
   }
 }
 
@@ -82,6 +95,21 @@ function getStringValue(value) {
   return stringValue;
 }
 
+function getValueType(value) {
+  if (value == null) {
+    return '' + value;
+  }
+
+  const t = typeof value;
+  if (t !== 'object') {
+    return t;
+  }
+  if (typeof value.constructor !== 'function') {
+    return t;
+  }
+  return value.constructor.name;
+}
+
 function getMessageFormat(schemaType) {
   const messageFormat = get(schemaType, 'options.cast', null);
   if (typeof messageFormat === 'string') {
@@ -93,7 +121,7 @@ function getMessageFormat(schemaType) {
  * ignore
  */
 
-function formatMessage(model, kind, stringValue, path, messageFormat) {
+function formatMessage(model, kind, stringValue, path, messageFormat, valueType) {
   if (messageFormat != null) {
     let ret = messageFormat.
       replace('{KIND}', kind).
@@ -105,8 +133,9 @@ function formatMessage(model, kind, stringValue, path, messageFormat) {
 
     return ret;
   } else {
+    let valueTypeMsg = valueType ? ' (type ' + valueType + ')' : '';
     let ret = 'Cast to ' + kind + ' failed for value ' +
-      stringValue + ' at path "' + path + '"';
+      stringValue + valueTypeMsg + ' at path "' + path + '"';
     if (model != null) {
       ret += ' for model "' + model.modelName + '"';
     }
diff --git a/test/docs/custom-casting.test.js b/test/docs/custom-casting.test.js
index bd9d8484702..601e80e41b0 100644
--- a/test/docs/custom-casting.test.js
+++ b/test/docs/custom-casting.test.js
@@ -28,7 +28,7 @@ describe('custom casting', function() {
     // "Cast to Number failed for value "二" at path "age""
     err.message;
     // acquit:ignore:start
-    assert.ok(err.message.indexOf('Cast to Number failed for value "二" at path "age"') !== -1, err.message);
+    assert.ok(err.message.indexOf('Cast to Number failed for value "二" (type string) at path "age"') !== -1, err.message);
     // acquit:ignore:end
   });
 
diff --git a/test/docs/schematypes.test.js b/test/docs/schematypes.test.js
index f3e454969b9..20acac5da72 100644
--- a/test/docs/schematypes.test.js
+++ b/test/docs/schematypes.test.js
@@ -61,7 +61,7 @@ describe('schemaTypes', function() {
     assert.ok(t.validateSync());
     assert.equal(t.validateSync().errors['test'].name, 'CastError');
     assert.equal(t.validateSync().errors['test'].message,
-      'Cast to Int8 failed for value "abc" at path "test"');
+      'Cast to Int8 failed for value "abc" (type string) at path "test"');
     assert.equal(t.validateSync().errors['test'].reason.message,
       'Int8: abc is not a number');
   });
diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 8304d4d067e..bfe421b5c83 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -376,7 +376,7 @@ describe('validation docs', function() {
     // acquit:ignore:start
     assert.equal(err.errors['numWheels'].name, 'CastError');
     assert.equal(err.errors['numWheels'].message,
-      'Cast to Number failed for value "not a number" at path "numWheels"');
+      'Cast to Number failed for value "not a number" (type string) at path "numWheels"');
     // acquit:ignore:end
   });
 
diff --git a/test/es-next/cast.test.es6.js b/test/es-next/cast.test.es6.js
index 92c76b6d05c..563cdeff0ab 100644
--- a/test/es-next/cast.test.es6.js
+++ b/test/es-next/cast.test.es6.js
@@ -88,7 +88,7 @@ describe('Cast Tutorial', function() {
     // acquit:ignore:start
     assert.ok(err instanceof mongoose.CastError);
     assert.equal(err.message, 'Cast to Number failed for value "not a ' +
-      'number" at path "age" for model "Character"');
+      'number" (type string) at path "age" for model "Character"');
     // acquit:ignore:end
   });
 
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 8502ea10227..66af0a97349 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -1691,7 +1691,7 @@ describe('model: findOneAndUpdate:', function() {
       Person.findOneAndUpdate({}, update, function(error) {
         assert.ok(error.message.indexOf('street') !== -1);
         assert.equal(error.reason.message,
-          'Cast to Number failed for value "not a num" at path "street"');
+          'Cast to Number failed for value "not a num" (type string) at path "street"');
         done();
       });
     });
diff --git a/test/model.querying.test.js b/test/model.querying.test.js
index 79e6bfad05d..4608f799b97 100644
--- a/test/model.querying.test.js
+++ b/test/model.querying.test.js
@@ -866,10 +866,10 @@ describe('model: querying:', function() {
             assert.equal(nes1.length, 1);
 
             NE.find({ b: { $ne: [1] } }, function(err) {
-              assert.equal(err.message, 'Cast to ObjectId failed for value "[ 1 ]" at path "b" for model "Test"');
+              assert.equal(err.message, 'Cast to ObjectId failed for value "[ 1 ]" (type Array) at path "b" for model "Test"');
 
               NE.find({ b: { $ne: 4 } }, function(err) {
-                assert.equal(err.message, 'Cast to ObjectId failed for value "4" at path "b" for model "Test"');
+                assert.equal(err.message, 'Cast to ObjectId failed for value "4" (type number) at path "b" for model "Test"');
 
                 NE.find({ b: id3, ids: { $ne: id4 } }, function(err, nes4) {
                   assert.ifError(err);
@@ -1807,7 +1807,7 @@ describe('model: querying:', function() {
 
           Test.findOne({ block: /buffer/i }, function(err) {
             assert.equal(err.message, 'Cast to Buffer failed for value ' +
-              '"/buffer/i" at path "block" for model "Test"');
+              '"/buffer/i" (type RegExp) at path "block" for model "Test"');
             Test.findOne({ block: [195, 188, 98, 101, 114] }, function(err, rb) {
               assert.ifError(err);
               assert.equal(rb.block.toString('utf8'), 'über');
diff --git a/test/schema.test.js b/test/schema.test.js
index 722bc73b0ec..1e1a6f1c34d 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -441,7 +441,7 @@ describe('schema', function() {
         threw = true;
         assert.equal(error.name, 'CastError');
         assert.equal(error.message,
-          'Cast to [[Number]] failed for value "[["abcd"]]" at path "nums.0"');
+          'Cast to [[Number]] failed for value "[["abcd"]]" (type string) at path "nums.0"');
       }
       assert.ok(threw);
 
diff --git a/test/schema.validation.test.js b/test/schema.validation.test.js
index 1e773fea9ee..52432acb8bc 100644
--- a/test/schema.validation.test.js
+++ b/test/schema.validation.test.js
@@ -1118,7 +1118,7 @@ describe('schema', function() {
       bad.validate(function(error) {
         assert.ok(error);
         const errorMessage = 'foods: Cast to Object failed for value ' +
-            '"waffles" at path "foods"';
+            '"waffles" (type string) at path "foods"';
         assert.ok(error.toString().indexOf(errorMessage) !== -1, error.toString());
         done();
       });
@@ -1192,7 +1192,7 @@ describe('schema', function() {
       const Breakfast = mongoose.model('gh2832', breakfast, 'gh2832');
       Breakfast.create({ description: undefined }, function(error) {
         assert.ok(error);
-        const errorMessage = 'ValidationError: description: Cast to String failed for value "undefined" at path "description"';
+        const errorMessage = 'ValidationError: description: Cast to String failed for value "undefined" (type undefined) at path "description"';
         assert.equal(errorMessage, error.toString());
         assert.ok(error.errors.description);
         assert.equal(error.errors.description.reason.toString(), 'Error: oops');
diff --git a/test/types.buffer.test.js b/test/types.buffer.test.js
index 308379431cd..df05c26582b 100644
--- a/test/types.buffer.test.js
+++ b/test/types.buffer.test.js
@@ -91,7 +91,7 @@ describe('types.buffer', function() {
           assert.equal(err.name, 'ValidationError');
           assert.equal(err.errors.required.name, 'CastError');
           assert.equal(err.errors.required.kind, 'Buffer');
-          assert.equal(err.errors.required.message, 'Cast to Buffer failed for value "{ x: [ 20 ] }" at path "required"');
+          assert.equal(err.errors.required.message, 'Cast to Buffer failed for value "{ x: [ 20 ] }" (type Object) at path "required"');
           assert.deepEqual(err.errors.required.value, { x: [20] });
           t.required = Buffer.from('hello');
 

From 478d8c9725c5d38c267a53924ab81ae9a5baf25a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 May 2021 10:24:33 -0400
Subject: [PATCH 2030/2348] fix(SchemaArrayOptions): correct property name

Fix #10236
---
 lib/options/SchemaArrayOptions.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/options/SchemaArrayOptions.js b/lib/options/SchemaArrayOptions.js
index 87544944713..e3734ae4992 100644
--- a/lib/options/SchemaArrayOptions.js
+++ b/lib/options/SchemaArrayOptions.js
@@ -50,7 +50,7 @@ Object.defineProperty(SchemaArrayOptions.prototype, 'enum', opts);
  * @instance
  */
 
-Object.defineProperty(SchemaArrayOptions.prototype, 'enum', opts);
+Object.defineProperty(SchemaArrayOptions.prototype, 'of', opts);
 
 /*!
  * ignore

From 92c9107b782593cd9511992fcf4f9d7fb3c7d92a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 May 2021 14:12:48 -0400
Subject: [PATCH 2031/2348] docs(typescript): add page describing how to use
 `populate()` with TypeScript

Fix #10212
---
 docs/layout.pug             |  2 ++
 docs/typescript/populate.md | 50 +++++++++++++++++++++++++++++++++++++
 test/typescript/populate.ts | 22 ++++++++++------
 3 files changed, 66 insertions(+), 8 deletions(-)
 create mode 100644 docs/typescript/populate.md

diff --git a/docs/layout.pug b/docs/layout.pug
index fbf187b728d..1f0eb00c6a3 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -106,6 +106,8 @@ html(lang='en')
                   a.pure-menu-link(href="/docs/typescript/statics.html", class=outputUrl === '/docs/typescript/statics.html' ? 'selected' : '') Statics
                 li.pure-menu-item.tertiary-item
                   a.pure-menu-link(href="/docs/typescript/query-helpers.html", class=outputUrl === '/docs/typescript/query-helpers.html' ? 'selected' : '') Query Helpers
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/typescript/populate.html", class=outputUrl === '/docs/typescript/populate.html' ? 'selected' : '') Populate
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
               li.pure-menu-item.sub-item
diff --git a/docs/typescript/populate.md b/docs/typescript/populate.md
new file mode 100644
index 00000000000..1d3203b2a22
--- /dev/null
+++ b/docs/typescript/populate.md
@@ -0,0 +1,50 @@
+# Populate with TypeScript
+
+[Mongoose's TypeScript bindings](https://thecodebarbarian.com/working-with-mongoose-in-typescript.html) export a `PopulatedDoc` type that helps you define populated documents in your TypeScript definitions:
+
+```typescript
+import { Schema, model, Document, PopulatedDoc } from 'mongoose';
+
+// `child` is either an ObjectId or a populated document
+interface Parent {
+  child?: PopulatedDoc<Child & Document>,
+  name?: string
+}
+const ParentModel = model<Parent>('Parent', new Schema({
+  child: { type: 'ObjectId', ref: 'Child' },
+  name: String
+}));
+
+interface Child {
+  name?: string;
+}
+const childSchema: Schema = new Schema({ name: String });
+const ChildModel = model<Child>('Child', childSchema);
+
+ParentModel.findOne({}).populate('child').orFail().then((doc: Parent) => {
+  // Works
+  doc.child.name.trim();
+});
+```
+
+Below is a simplified implementation of the `PopulatedDoc` type. It takes 2 generic parameters: the populated document type `PopulatedType`, and the unpopulated type `RawId`.
+`RawId` defaults to an ObjectId.
+
+```typescript
+type PopulatedDoc<PopulatedType, RawId = Types.ObjectId> = PopulatedType | RawId;
+```
+
+You as the developer are responsible for enforcing strong typing between populated and non-populated docs.
+Below is an example.
+
+```typescript
+ParentModel.findOne({}).populate('child').orFail().then((doc: Parent) => {
+  // `doc` doesn't have type information that `child` is populated
+  useChildDoc(doc.child);
+});
+
+// You can use a function signature to make type checking more strict.
+function useChildDoc(child: Child): void {
+  console.log(child.name.trim());
+}
+```
\ No newline at end of file
diff --git a/test/typescript/populate.ts b/test/typescript/populate.ts
index b7bb1674140..5020e8660c8 100644
--- a/test/typescript/populate.ts
+++ b/test/typescript/populate.ts
@@ -1,20 +1,26 @@
 import { Schema, model, Document, PopulatedDoc } from 'mongoose';
 
-interface IChild extends Document { name?: string }
+interface Child {
+  name: string;
+}
 
 const childSchema: Schema = new Schema({ name: String });
-const Child = model<IChild>('Child', childSchema);
+const ChildModel = model<Child>('Child', childSchema);
 
-interface IParent extends Document {
-  child?: PopulatedDoc<IChild>,
+interface Parent {
+  child?: PopulatedDoc<Child & Document>,
   name?: string
 }
 
-const Parent = model<IParent>('Parent', new Schema({
+const ParentModel = model<Parent>('Parent', new Schema({
   child: { type: 'ObjectId', ref: 'Child' },
   name: String
 }));
 
-Parent.findOne({}).populate('child').orFail().then((doc: IParent) => {
-  doc.child.name.trim();
-});
\ No newline at end of file
+ParentModel.findOne({}).populate('child').orFail().then((doc: Parent) => {
+  useChildDoc(doc.child);
+});
+
+function useChildDoc(child: Child): void {
+  console.log(child.name.trim());
+}
\ No newline at end of file

From a5968d6eff772e1e5385a696be38f2b9b07b05a2 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 14 May 2021 15:26:44 -0400
Subject: [PATCH 2032/2348] rough draft

---
 lib/document.js     | 28 ++++++++++++++++++++--------
 lib/model.js        |  1 -
 lib/query.js        |  1 -
 lib/queryhelpers.js | 10 ++++++----
 4 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f7aa890dc3e..559a7c2cf0a 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -70,7 +70,6 @@ const specialProperties = utils.specialProperties;
  */
 
 function Document(obj, fields, skipId, options) {
-  console.log('doc', new Error().stack)
   if (typeof skipId === 'object' && skipId != null) {
     options = skipId;
     skipId = options.skipId;
@@ -78,7 +77,6 @@ function Document(obj, fields, skipId, options) {
   options = Object.assign({}, options);
   const defaults = get(options, 'defaults', true);
   options.defaults = defaults;
-
   // Support `browserDocument.js` syntax
   if (this.$__schema == null) {
     const _schema = utils.isObject(fields) && !fields.instanceOfSchema ?
@@ -97,7 +95,6 @@ function Document(obj, fields, skipId, options) {
   this.$__.$options = options || {};
   this.$locals = {};
   this.$op = null;
-  console.log(this);
   if (obj != null && typeof obj !== 'object') {
     throw new ObjectParameterError(obj, 'obj', 'Document');
   }
@@ -137,7 +134,6 @@ function Document(obj, fields, skipId, options) {
     // By default, defaults get applied **before** setting initial values
     // Re: gh-6155
     if (defaults) {
-      console.log('z')
       $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, true, {
         isNew: this.isNew
       });
@@ -160,17 +156,19 @@ function Document(obj, fields, skipId, options) {
   // see the full doc rather than an empty one, unless they opt out.
   // Re: gh-3781, gh-6155
   if (options.willInit && defaults) {
-    console.log('a');
     EventEmitter.prototype.once.call(this, 'init', () => {
       $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
         isNew: this.isNew
       });
     });
   } else if (defaults) {
-    console.log('b');
     $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
       isNew: this.isNew
     });
+  } else if (!defaults) {
+    EventEmitter.prototype.once.call(this, 'init', () => {
+      $__unapplyDefaults(this);
+    });
   }
 
   this.$__._id = this._id;
@@ -348,7 +346,6 @@ function $__hasIncludedChildren(fields) {
  */
 
 function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isBeforeSetters, pathsToSkip) {
-  console.log('the values', doc,fields,skipId, exclude, hasIncludedChildren, isBeforeSetters, pathsToSkip);
   const paths = Object.keys(doc.$__schema.paths);
   const plen = paths.length;
 
@@ -366,7 +363,6 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
     const len = path.length;
     let included = false;
     let doc_ = doc._doc;
-
     for (let j = 0; j < len; ++j) {
       if (doc_ == null) {
         break;
@@ -459,6 +455,22 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
     }
   }
 }
+/**
+ * Checks which paths have defaults
+ * to then delete them from the doc
+ * 
+ * @param {Object} doc 
+ */
+function $__unapplyDefaults(doc) {
+  var values = Object.values(doc.$__schema.paths);
+  for (let i = 0; i < values.length; i++) {
+    if(values[i].defaultValue && values[i].instance != 'ObjectID') {
+      let property = values[i].path;
+      delete doc._doc[property];
+    }
+  }
+
+}
 
 /**
  * Builds the default doc structure
diff --git a/lib/model.js b/lib/model.js
index 5bbfcf33658..b40b8c035cd 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4673,7 +4673,6 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
   } else {
     // generate new class
     model = function model(doc, fields, skipId) {
-      console.log('this is the object being sent', skipId);
       model.hooks.execPreSync('createModel', doc);
       if (!(this instanceof model)) {
         return new model(doc, fields, skipId);
diff --git a/lib/query.js b/lib/query.js
index 205ba1df94c..00e385817a4 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2947,7 +2947,6 @@ Query.prototype._deleteMany = wrapThunk(function(callback) {
  */
 
 function completeOne(model, doc, res, options, fields, userProvidedFields, pop, callback) {
-  console.log(options);
   const opts = pop ?
     { populated: pop }
     : undefined;
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index acf3a42340b..c696e293962 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -86,8 +86,6 @@ exports.preparePopulationOptionsMQ = function preparePopulationOptionsMQ(query,
  * @return {Document}
  */
 exports.createModel = function createModel(model, doc, fields, userProvidedFields, options) {
-  console.log('this is options in createModel', options)
-  console.log(new Error().stack);
   model.hooks.execPreSync('createModel', doc);
   const discriminatorMapping = model.schema ?
     model.schema.discriminatorMapping :
@@ -106,11 +104,15 @@ exports.createModel = function createModel(model, doc, fields, userProvidedField
       return new discriminator(undefined, _fields, true);
     }
   }
-
+if (typeof options === 'undefined') {
+  options = {};
+  options.defaults = true
+}
   return new model(undefined, fields, {
     skipId: true,
     isNew: false,
-    willInit: true
+    willInit: true,
+    defaults: options.defaults
   });
 };
 

From 86afc1c29e479e5dde4d321392a48db2057b9150 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 14 May 2021 15:27:42 -0400
Subject: [PATCH 2033/2348] Update queryhelpers.js

---
 lib/queryhelpers.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index c696e293962..f9e7215225f 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -106,7 +106,7 @@ exports.createModel = function createModel(model, doc, fields, userProvidedField
   }
 if (typeof options === 'undefined') {
   options = {};
-  options.defaults = true
+  options.defaults = true;
 }
   return new model(undefined, fields, {
     skipId: true,

From 35a81807e773445ad1051af36a6ee6bcc89d1229 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 14 May 2021 15:28:02 -0400
Subject: [PATCH 2034/2348] Update model.test.js

---
 test/model.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/model.test.js b/test/model.test.js
index 2d9a45ff5fb..b7aa7d5c393 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7214,7 +7214,6 @@ describe('Model', function() {
     return co(function*() {
       const doc = yield Beta.create({ age: 21 });
       const test = yield Beta.findOne({ _id: doc.id }).setOptions({ defaults: false });
-      console.log('this is from the test', test);
       assert.ok(!test.name);
     });
   });

From e9a0e2631d492bc97af7b6cb079b2ea17f3a3cec Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 14 May 2021 15:32:02 -0400
Subject: [PATCH 2035/2348] linter fix

---
 lib/document.js     | 10 +++++-----
 lib/query.js        |  2 +-
 lib/queryhelpers.js |  8 ++++----
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 559a7c2cf0a..0925e72c830 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -458,14 +458,14 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
 /**
  * Checks which paths have defaults
  * to then delete them from the doc
- * 
- * @param {Object} doc 
+ *
+ * @param {Object} doc
  */
 function $__unapplyDefaults(doc) {
-  var values = Object.values(doc.$__schema.paths);
+  let values = Object.values(doc.$__schema.paths);
   for (let i = 0; i < values.length; i++) {
-    if(values[i].defaultValue && values[i].instance != 'ObjectID') {
-      let property = values[i].path;
+    if (values[i].defaultValue && values[i].instance != 'ObjectID') {
+      const property = values[i].path;
       delete doc._doc[property];
     }
   }
diff --git a/lib/query.js b/lib/query.js
index 00e385817a4..a3a6682f6f8 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2956,7 +2956,7 @@ function completeOne(model, doc, res, options, fields, userProvidedFields, pop,
     return null;
   }
 
-  const casted = helpers.createModel(model, doc, fields, userProvidedFields,options);
+  const casted = helpers.createModel(model, doc, fields, userProvidedFields, options);
   try {
     casted.init(doc, opts, _init);
   } catch (error) {
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index f9e7215225f..c371f6399ab 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -104,10 +104,10 @@ exports.createModel = function createModel(model, doc, fields, userProvidedField
       return new discriminator(undefined, _fields, true);
     }
   }
-if (typeof options === 'undefined') {
-  options = {};
-  options.defaults = true;
-}
+  if (typeof options === 'undefined') {
+    options = {};
+    options.defaults = true;
+  }
   return new model(undefined, fields, {
     skipId: true,
     isNew: false,

From bffc12627d5e70a6bbbcc02fe0d02bb62321f284 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 14 May 2021 16:59:20 -0400
Subject: [PATCH 2036/2348] docs: switch from AWS to Azure Functions for search

Fix #10244
---
 docs/js/search.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/js/search.js b/docs/js/search.js
index 9b824fd40d0..71c623502e2 100644
--- a/docs/js/search.js
+++ b/docs/js/search.js
@@ -1,4 +1,4 @@
-var root = 'https://8jekzv4pyd.execute-api.us-east-1.amazonaws.com/prod';
+var root = 'https://mongoosejs.azurewebsites.net/api';
 var pairs = window.location.search.replace(/^\?/, '').split('&');
 
 var q = null;

From df55943b8ab1b11c3e3659c4599742e7b9e65b3d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 14 May 2021 17:07:04 -0400
Subject: [PATCH 2037/2348] updated to work with older versions of node
 hopefully

---
 lib/document.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 0925e72c830..72fe20df403 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -462,14 +462,14 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
  * @param {Object} doc
  */
 function $__unapplyDefaults(doc) {
-  let values = Object.values(doc.$__schema.paths);
-  for (let i = 0; i < values.length; i++) {
-    if (values[i].defaultValue && values[i].instance != 'ObjectID') {
-      const property = values[i].path;
+  const keys = Object.keys(doc.$__schema.paths);
+  for (let i = 0; i < keys.length; i++) {
+    const key = keys[i]
+    if (doc.$__schema.paths[key].defaultValue && doc.$__schema.paths[key].instance != 'ObjectID') {
+      const property = doc.$__schema.paths[key].path;
       delete doc._doc[property];
     }
   }
-
 }
 
 /**

From fc9706b3e21bb8d1df120e540791348dc3c97e14 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 14 May 2021 17:21:26 -0400
Subject: [PATCH 2038/2348] update

---
 lib/document.js | 2 +-
 lib/query.js    | 4 +---
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 72fe20df403..8932cea1cba 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -464,7 +464,7 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
 function $__unapplyDefaults(doc) {
   const keys = Object.keys(doc.$__schema.paths);
   for (let i = 0; i < keys.length; i++) {
-    const key = keys[i]
+    const key = keys[i];
     if (doc.$__schema.paths[key].defaultValue && doc.$__schema.paths[key].instance != 'ObjectID') {
       const property = doc.$__schema.paths[key].path;
       delete doc._doc[property];
diff --git a/lib/query.js b/lib/query.js
index a3a6682f6f8..7b652b14566 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1439,10 +1439,8 @@ Query.prototype.setOptions = function(options, overwrite) {
   }
 
   if ('defaults' in options) {
-    // console.log('this is options in setOptions', options);
-    // console.log(new Error().stack);
     this._mongooseOptions.defaults = options.defaults;
-    // delete options.defaults;
+    // deleting options.defaults will cause 7287 to fail
   }
 
   return Query.base.setOptions.call(this, options);

From a6af1384945b2f9406bfc47ca0cf77f9f316842b Mon Sep 17 00:00:00 2001
From: Boris Figovsky <boris@hysolate.com>
Date: Sat, 15 May 2021 17:02:41 +0000
Subject: [PATCH 2039/2348] ts: fix query async iterator definition

Fixes #10250

1. The async iterator is supposed to be a method and not a property;
2. According to underlying implementation, it returns an asyncIterator
   and not a query cursor.
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 835b73b4f16..e4874d105b5 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1876,7 +1876,7 @@ declare module 'mongoose' {
      * A QueryCursor exposes a Streams3 interface, as well as a `.next()` function.
      * This is equivalent to calling `.cursor()` with no arguments.
      */
-    [Symbol.asyncIterator]: QueryCursor<DocType>;
+    [Symbol.asyncIterator](): AsyncIterableIterator<DocType>;
 
     /** Executes the query */
     exec(): Promise<ResultType>;

From 71c5dde89f6ccce05b15b125520a4611413e3341 Mon Sep 17 00:00:00 2001
From: Boris Figovsky <boris@hysolate.com>
Date: Sat, 15 May 2021 17:35:31 +0000
Subject: [PATCH 2040/2348] ts: strictly typed query cursor async iterator

Closes #10252
---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 835b73b4f16..48e61103f6a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2368,6 +2368,8 @@ declare module 'mongoose' {
     T;
 
   class QueryCursor<DocType extends Document> extends stream.Readable {
+    [Symbol.asyncIterator](): AsyncIterableIterator<DocType>;
+
     /**
      * Adds a [cursor flag](http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag).
      * Useful for setting the `noCursorTimeout` and `tailable` flags.

From e61def33ff18017990e27b4dc0072b1dccd59e24 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 16 May 2021 19:37:23 -0400
Subject: [PATCH 2041/2348] fix(index.d.ts): add `any` to all query operators
 to minimize likelihood of "type instantiation is excessively deep" when
 querying docs with 4-level deep subdocs

Fix #10189
---
 index.d.ts | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e02f864e004..e18b1f75881 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2298,22 +2298,22 @@ declare module 'mongoose' {
   /** @see https://docs.mongodb.com/manual/reference/operator/update */
   type _UpdateQuery<TSchema> = {
     /** @see https://docs.mongodb.com/manual/reference/operator/update-field/ */
-    $currentDate?: mongodb.OnlyFieldsOfType<TSchema, NativeDate | mongodb.Timestamp, true | { $type: 'date' | 'timestamp' }>;
-    $inc?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined>;
+    $currentDate?: mongodb.OnlyFieldsOfType<TSchema, NativeDate | mongodb.Timestamp, true | { $type: 'date' | 'timestamp' }> | any;
+    $inc?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined> | any;
     $min?: mongodb.MatchKeysAndValues<TSchema>;
     $max?: mongodb.MatchKeysAndValues<TSchema>;
-    $mul?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined>;
+    $mul?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined> | any;
     $rename?: { [key: string]: string };
     $set?: mongodb.MatchKeysAndValues<TSchema>;
     $setOnInsert?: mongodb.MatchKeysAndValues<TSchema>;
-    $unset?: mongodb.OnlyFieldsOfType<TSchema, any, any>;
+    $unset?: mongodb.OnlyFieldsOfType<TSchema, any, any> | any;
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-array/ */
-    $addToSet?: mongodb.SetFields<TSchema>;
-    $pop?: mongodb.OnlyFieldsOfType<TSchema, ReadonlyArray<any>, 1 | -1>;
+    $addToSet?: mongodb.SetFields<TSchema> | any;
+    $pop?: mongodb.OnlyFieldsOfType<TSchema, ReadonlyArray<any>, 1 | -1> | any;
     $pull?: PullOperator<TSchema>;
     $push?: mongodb.PushOperator<TSchema> | any;
-    $pullAll?: mongodb.PullAllOperator<TSchema>;
+    $pullAll?: mongodb.PullAllOperator<TSchema> | any;
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-bitwise/ */
     $bit?: {

From 70340a2c131ccbb4bbd40320c8fa19969c91be37 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 17 May 2021 12:34:03 -0400
Subject: [PATCH 2042/2348] made requested changes

---
 lib/document.js    | 20 --------------------
 test/model.test.js |  7 ++++---
 2 files changed, 4 insertions(+), 23 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 8932cea1cba..931b2d4f8c7 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -165,10 +165,6 @@ function Document(obj, fields, skipId, options) {
     $__applyDefaults(this, fields, skipId, exclude, hasIncludedChildren, false, options.skipDefaults, {
       isNew: this.isNew
     });
-  } else if (!defaults) {
-    EventEmitter.prototype.once.call(this, 'init', () => {
-      $__unapplyDefaults(this);
-    });
   }
 
   this.$__._id = this._id;
@@ -455,22 +451,6 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
     }
   }
 }
-/**
- * Checks which paths have defaults
- * to then delete them from the doc
- *
- * @param {Object} doc
- */
-function $__unapplyDefaults(doc) {
-  const keys = Object.keys(doc.$__schema.paths);
-  for (let i = 0; i < keys.length; i++) {
-    const key = keys[i];
-    if (doc.$__schema.paths[key].defaultValue && doc.$__schema.paths[key].instance != 'ObjectID') {
-      const property = doc.$__schema.paths[key].path;
-      delete doc._doc[property];
-    }
-  }
-}
 
 /**
  * Builds the default doc structure
diff --git a/test/model.test.js b/test/model.test.js
index b7aa7d5c393..0d5813675a2 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7207,13 +7207,14 @@ describe('Model', function() {
   it('supports skipping defaults on a find operation gh-7287', function() {
     const betaSchema = new Schema({
       name: { type: String, default: 'foo' },
-      age: { type: Number }
+      age: { type: Number },
+      _id: { type: Number }
     });
 
     const Beta = db.model('Beta', betaSchema);
     return co(function*() {
-      const doc = yield Beta.create({ age: 21 });
-      const test = yield Beta.findOne({ _id: doc.id }).setOptions({ defaults: false });
+      yield Beta.collection.insertOne({ age: 21, _id: 1 });
+      const test = yield Beta.findOne({ _id: 1 }).setOptions({ defaults: false });
       assert.ok(!test.name);
     });
   });

From 93213081c342b5c325127e6e3cfb26321a9c01f9 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 17 May 2021 14:52:50 -0400
Subject: [PATCH 2043/2348] added $__collection

---
 lib/model.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index 3bb4f38ede7..d2b6dd5f5fd 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -138,6 +138,7 @@ Model.prototype.db;
  */
 
 Model.prototype.collection;
+Model.prototype.$__collection;
 
 /**
  * The name of the model
@@ -1762,6 +1763,7 @@ Model.db;
  */
 
 Model.collection;
+Model.$__collection;
 
 /**
  * Base Mongoose instance the model uses.
@@ -4743,6 +4745,7 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
 
   model.schema = model.prototype.$__schema;
   model.collection = model.prototype.collection;
+  model.$__collection = model.collection;
 
   // Create custom query constructor
   model.Query = function() {
@@ -4825,6 +4828,7 @@ Model.__subclass = function subclass(conn, schema, collection) {
   Model.prototype.collection = conn.collection(collection, collectionOptions);
   Model.prototype[modelCollectionSymbol] = Model.prototype.collection;
   Model.collection = Model.prototype.collection;
+  Model.$__collection = Model.collection;
   // Errors handled internally, so ignore
   Model.init(() => {});
   return Model;

From 76af6e410845d9415c6bb5099472aee6c9fac585 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 17 May 2021 15:25:00 -0400
Subject: [PATCH 2044/2348] Update model.js

---
 lib/model.js | 62 ++++++++++++++++++++++++++--------------------------
 1 file changed, 31 insertions(+), 31 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index d2b6dd5f5fd..00e1372e4d1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1150,7 +1150,7 @@ Model.discriminator = function(name, schema, value) {
   schema.$isRootDiscriminator = true;
   schema.$globalPluginsApplied = true;
 
-  model = this.db.model(model || name, schema, this.collection.name);
+  model = this.db.model(model || name, schema, this.$__collection.name);
   this.discriminators[name] = model;
   const d = this.discriminators[name];
   d.prototype.__proto__ = this.prototype;
@@ -1336,12 +1336,12 @@ Model.createCollection = function createCollection(options, callback) {
   return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
-    this.db.createCollection(this.collection.collectionName, options, utils.tick((error) => {
+    this.db.createCollection(this.$__collection.collectionName, options, utils.tick((error) => {
       if (error != null && error.codeName !== 'NamespaceExists') {
         return cb(error);
       }
-      this.collection = this.db.collection(this.collection.collectionName, options);
-      cb(null, this.collection);
+      this.$__collection = this.db.collection(this.$__collection.collectionName, options);
+      cb(null, this.$__collection);
     }));
   }, this.events);
 };
@@ -1414,7 +1414,7 @@ Model.cleanIndexes = function cleanIndexes(callback) {
   callback = this.$handleCallbackError(callback);
 
   return this.db.base._promiseOrCallback(callback, cb => {
-    const collection = this.collection;
+    const collection = this.$__collection;
 
     this.listIndexes((err, indexes) => {
       if (err != null) {
@@ -1485,7 +1485,7 @@ Model.listIndexes = function init(callback) {
   _checkContext(this, 'listIndexes');
 
   const _listIndexes = cb => {
-    this.collection.listIndexes().toArray(cb);
+    this.$__collection.listIndexes().toArray(cb);
   };
 
   callback = this.$handleCallbackError(callback);
@@ -1494,8 +1494,8 @@ Model.listIndexes = function init(callback) {
     cb = this.$wrapCallback(cb);
 
     // Buffering
-    if (this.collection.buffer) {
-      this.collection.addQueue(_listIndexes, [cb]);
+    if (this.$__collection.buffer) {
+      this.$__collection.addQueue(_listIndexes, [cb]);
     } else {
       _listIndexes(cb);
     }
@@ -1914,7 +1914,7 @@ Model.remove = function remove(conditions, options, callback) {
   }
 
   // get the mongodb collection object
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.setOptions(options);
 
   callback = this.$handleCallbackError(callback);
@@ -1956,7 +1956,7 @@ Model.deleteOne = function deleteOne(conditions, options, callback) {
     options = null;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.setOptions(options);
 
   callback = this.$handleCallbackError(callback);
@@ -1997,7 +1997,7 @@ Model.deleteMany = function deleteMany(conditions, options, callback) {
     options = null;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.setOptions(options);
 
   callback = this.$handleCallbackError(callback);
@@ -2056,7 +2056,7 @@ Model.find = function find(conditions, projection, options, callback) {
     options = null;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.select(projection);
 
   mq.setOptions(options);
@@ -2169,7 +2169,7 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
     options = null;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.select(projection);
 
   mq.setOptions(options);
@@ -2203,7 +2203,7 @@ Model.findOne = function findOne(conditions, projection, options, callback) {
 Model.estimatedDocumentCount = function estimatedDocumentCount(options, callback) {
   _checkContext(this, 'estimatedDocumentCount');
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
 
   callback = this.$handleCallbackError(callback);
 
@@ -2247,7 +2247,7 @@ Model.countDocuments = function countDocuments(conditions, callback) {
     conditions = {};
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
 
   callback = this.$handleCallbackError(callback);
 
@@ -2283,7 +2283,7 @@ Model.count = function count(conditions, callback) {
     conditions = {};
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
 
   callback = this.$handleCallbackError(callback);
 
@@ -2317,7 +2317,7 @@ Model.count = function count(conditions, callback) {
 Model.distinct = function distinct(field, conditions, callback) {
   _checkContext(this, 'distinct');
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
 
   if (typeof conditions === 'function') {
     callback = conditions;
@@ -2356,7 +2356,7 @@ Model.where = function where(path, val) {
   _checkContext(this, 'where');
 
   void val; // eslint
-  const mq = new this.Query({}, {}, this, this.collection).find({});
+  const mq = new this.Query({}, {}, this, this.$__collection).find({});
   return mq.where.apply(mq, arguments);
 };
 
@@ -2378,7 +2378,7 @@ Model.where = function where(path, val) {
 Model.$where = function $where() {
   _checkContext(this, '$where');
 
-  const mq = new this.Query({}, {}, this, this.collection).find({});
+  const mq = new this.Query({}, {}, this, this.$__collection).find({});
   return mq.$where.apply(mq, arguments);
 };
 
@@ -2495,7 +2495,7 @@ Model.findOneAndUpdate = function(conditions, update, options, callback) {
 
   _decorateUpdateWithVersionKey(update, options, this.schema.options.versionKey);
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.select(fields);
 
   return mq.findOneAndUpdate(conditions, update, options, callback);
@@ -2714,7 +2714,7 @@ Model.findOneAndDelete = function(conditions, options, callback) {
     options.select = undefined;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.select(fields);
 
   return mq.findOneAndDelete(conditions, options, callback);
@@ -2832,7 +2832,7 @@ Model.findOneAndReplace = function(filter, replacement, options, callback) {
     options.select = undefined;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.select(fields);
 
   return mq.findOneAndReplace(filter, replacement, options, callback);
@@ -2918,7 +2918,7 @@ Model.findOneAndRemove = function(conditions, options, callback) {
     options.select = undefined;
   }
 
-  const mq = new this.Query({}, {}, this, this.collection);
+  const mq = new this.Query({}, {}, this, this.$__collection);
   mq.select(fields);
 
   return mq.findOneAndRemove(conditions, options, callback);
@@ -3154,16 +3154,16 @@ Model.watch = function(pipeline, options) {
   _checkContext(this, 'watch');
 
   const changeStreamThunk = cb => {
-    if (this.collection.buffer) {
-      this.collection.addQueue(() => {
+    if (this.$__collection.buffer) {
+      this.$__collection.addQueue(() => {
         if (this.closed) {
           return;
         }
-        const driverChangeStream = this.collection.watch(pipeline, options);
+        const driverChangeStream = this.$__collection.watch(pipeline, options);
         cb(null, driverChangeStream);
       });
     } else {
-      const driverChangeStream = this.collection.watch(pipeline, options);
+      const driverChangeStream = this.$__collection.watch(pipeline, options);
       cb(null, driverChangeStream);
     }
   };
@@ -3342,7 +3342,7 @@ Model.$__insertMany = function(arr, options, callback) {
       return doc.toObject(internalToObjectOptions);
     });
 
-    _this.collection.insertMany(docObjects, options, function(error, res) {
+    _this.$__collection.insertMany(docObjects, options, function(error, res) {
       if (error) {
         // `writeErrors` is a property reported by the MongoDB driver,
         // just not if there's only 1 error.
@@ -3537,7 +3537,7 @@ Model.bulkWrite = function(ops, options, callback) {
         return cb(null, getDefaultBulkwriteResult());
       }
 
-      this.collection.bulkWrite(ops, options, (error, res) => {
+      this.$__collection.bulkWrite(ops, options, (error, res) => {
         if (error) {
           return cb(error);
         }
@@ -3917,7 +3917,7 @@ Model.mapReduce = function mapReduce(o, callback) {
       q = undefined;
     }
 
-    this.collection.mapReduce(null, null, o, (err, res) => {
+    this.$__collection.mapReduce(null, null, o, (err, res) => {
       if (err) {
         return cb(err);
       }
@@ -4203,7 +4203,7 @@ Model.geoSearch = function(conditions, options, callback) {
     // send the conditions in the options object
     options.search = conditions;
 
-    this.collection.geoHaystackSearch(options.near[0], options.near[1], options, (err, res) => {
+    this.$__collection.geoHaystackSearch(options.near[0], options.near[1], options, (err, res) => {
       if (err) {
         return cb(err);
       }

From 1985c9464b2eddd2dd81daa51e29e0d8e478eef4 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 17 May 2021 15:27:48 -0400
Subject: [PATCH 2045/2348] added comments

---
 lib/model.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index 00e1372e4d1..b496c016209 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -138,6 +138,19 @@ Model.prototype.db;
  */
 
 Model.prototype.collection;
+
+/**
+ * Internal collection the model uses.
+ *
+ * This property is read-only. Modifying this property is a no-op.
+ *
+ * @api private
+ * @property collection
+ * @memberOf Model
+ * @instance
+ */
+
+
 Model.prototype.$__collection;
 
 /**
@@ -1763,6 +1776,14 @@ Model.db;
  */
 
 Model.collection;
+
+/**
+ * Internal collection the model uses.
+ *
+ * @property collection
+ * @api private
+ * @memberOf Model
+ */
 Model.$__collection;
 
 /**

From 79a71cb02d40dd46fd684fb095f21f05dd445753 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 17 May 2021 21:02:26 -0400
Subject: [PATCH 2046/2348] fix(index.d.ts): use `$parent()` instead of
 `parent()` in TS definitions

---
 index.d.ts | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index bf812684de8..ed1e9e762cb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -546,7 +546,7 @@ declare module 'mongoose' {
      * If this document is a subdocument or populated document, returns the 
      * document's parent. Returns undefined otherwise.
      */
-    parent(): Document | undefined;
+    $parent(): Document | undefined;
 
     /**
      * Populates document references, executing the `callback` when complete.
@@ -1827,6 +1827,9 @@ declare module 'mongoose' {
 
       /** Returns this sub-documents parent document. */
       parent(): Document;
+      
+      /** Returns this sub-documents parent document. */
+      $parent(): Document;
 
       /** Returns this sub-documents parent array. */
       parentArray(): DocumentArray<Document>;
@@ -1861,6 +1864,9 @@ declare module 'mongoose' {
 
       /** Returns this sub-documents parent document. */
       parent(): Document;
+      
+      /** Returns this sub-documents parent document. */
+      $parent(): Document;
     }
   }
 

From 94291bee9ab51cdac3a2371b445e7a08e7e48285 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 17 May 2021 21:27:10 -0400
Subject: [PATCH 2047/2348] style: fix lint

---
 index.d.ts        | 6 +++---
 lib/error/cast.js | 2 +-
 lib/query.js      | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 41e72a19637..0441ff862dc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -543,7 +543,7 @@ declare module 'mongoose' {
     overwrite(obj: DocumentDefinition<this>): this;
 
     /**
-     * If this document is a subdocument or populated document, returns the 
+     * If this document is a subdocument or populated document, returns the
      * document's parent. Returns undefined otherwise.
      */
     $parent(): Document | undefined;
@@ -1833,7 +1833,7 @@ declare module 'mongoose' {
 
       /** Returns this sub-documents parent document. */
       parent(): Document;
-      
+
       /** Returns this sub-documents parent document. */
       $parent(): Document;
 
@@ -1870,7 +1870,7 @@ declare module 'mongoose' {
 
       /** Returns this sub-documents parent document. */
       parent(): Document;
-      
+
       /** Returns this sub-documents parent document. */
       $parent(): Document;
     }
diff --git a/lib/error/cast.js b/lib/error/cast.js
index 794aadd761c..dc604b58211 100644
--- a/lib/error/cast.js
+++ b/lib/error/cast.js
@@ -133,7 +133,7 @@ function formatMessage(model, kind, stringValue, path, messageFormat, valueType)
 
     return ret;
   } else {
-    let valueTypeMsg = valueType ? ' (type ' + valueType + ')' : '';
+    const valueTypeMsg = valueType ? ' (type ' + valueType + ')' : '';
     let ret = 'Cast to ' + kind + ' failed for value ' +
       stringValue + valueTypeMsg + ' at path "' + path + '"';
     if (model != null) {
diff --git a/lib/query.js b/lib/query.js
index 3b8ead91892..0f7fd5da67a 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -962,7 +962,7 @@ Query.prototype.select = function select() {
   if (utils.isObject(arg)) {
     const keys = Object.keys(arg);
     for (let i = 0; i < keys.length; ++i) {
-      let value = arg[keys[i]];
+      const value = arg[keys[i]];
       fields[keys[i]] = value;
       userProvidedFields[keys[i]] = value;
     }

From 616be955da9aa48805a98f3e3a97b239527d5fc5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 18 May 2021 09:21:36 -0400
Subject: [PATCH 2048/2348] fix(document): allow passing space-delimited string
 of `pathsToValidate` to `validate()` and `validateSync()`

Fix #10258
---
 lib/document.js       | 7 +++++++
 test/document.test.js | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 931b2d4f8c7..5d11879b455 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2455,6 +2455,10 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     pathDetails[0].filter((path) => this.isModified(path)) :
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
+
+  if (typeof pathsToValidate === 'string') {
+    pathsToValidate = pathsToValidate.split(' ');
+  }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }
@@ -2633,6 +2637,9 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
 
+  if (typeof pathsToValidate === 'string') {
+    pathsToValidate = pathsToValidate.split(' ');
+  }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }
diff --git a/test/document.test.js b/test/document.test.js
index 9be6f4025d6..debeab2d62d 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -2535,6 +2535,8 @@ describe('document', function() {
         doc.other = 'something';
         doc.subdocs[1].name = 'test2';
         assert.equal(doc.validateSync({ validateModifiedOnly: true }), null);
+        assert.equal(doc.validateSync('other'), null);
+        assert.ok(doc.validateSync('other title').errors['title']);
         doc.save({ validateModifiedOnly: true }, function(error) {
           assert.equal(error, null);
           done();

From 4c7e5dea95a0491642e3c5ac1d64f4f4e84a485a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 18 May 2021 10:02:06 -0400
Subject: [PATCH 2049/2348] test(populate): repro #10231

---
 test/model.populate.test.js | 47 +++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 82d9ef4ad9d..fd6e96823a6 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10415,4 +10415,51 @@ describe('model: populate:', function() {
       assert.equal(res[1].params[0].value.optionLabels[0].name, 'test');
     });
   });
+
+  it('populates embedded discriminator with tied value (gh-10231)', function() {
+    const GuestSchema = new Schema({
+      dummy: String
+    });
+
+    const ActivitySchema = new Schema({
+      title: String,
+      kind: { required: true, type: String, enum: ['TALK'] } },
+    { discriminatorKey: 'kind' });
+
+    const ActivityTalkSchema = new Schema({
+      speakers: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Guest' }]
+    });
+
+    ActivityTalkSchema.add(ActivitySchema);
+
+    ActivityTalkSchema.paths.kind.options.$skipDiscriminatorCheck = true;
+
+    const ProgrammeSchema = new Schema({
+      activities: [{ required: true, type: ActivitySchema }]
+    });
+
+    ProgrammeSchema.path('activities').discriminator('ActivityTalk', ActivityTalkSchema, 'TALK');
+
+    const GuestModel = db.model('Guest', GuestSchema);
+    const ProgrammeModel = db.model('Test', ProgrammeSchema);
+
+    return co(function*() {
+      const guest1 = yield GuestModel.create({ dummy: '1' });
+      const guest2 = yield GuestModel.create({ dummy: '2' });
+
+      const programme1 = yield ProgrammeModel.create({
+        activities: [
+          { title: 'hello', kind: 'TALK', speakers: [guest1, guest2] }
+        ]
+      });
+
+      const event = yield ProgrammeModel.findOne({ _id: programme1._id }).orFail().exec();
+      yield event.populate({ path: 'activities.speakers' }).execPopulate();
+      assert.equal(event.activities.length, 1);
+      assert.equal(event.activities[0].speakers.length, 2);
+      assert.equal(event.activities[0].speakers[0].dummy, '1');
+      assert.equal(event.activities[0].speakers[1].dummy, '2');
+
+    });
+  });
 });

From 07a527cabad1fb2710abeb81adbad371c66f8b88 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 18 May 2021 10:07:29 -0400
Subject: [PATCH 2050/2348] fix(populate): handle populating embedded
 discriminator with custom tiedValue

Fix #10231
---
 lib/helpers/populate/getSchemaTypes.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getSchemaTypes.js b/lib/helpers/populate/getSchemaTypes.js
index c500d802d87..4c33ebb3486 100644
--- a/lib/helpers/populate/getSchemaTypes.js
+++ b/lib/helpers/populate/getSchemaTypes.js
@@ -50,7 +50,8 @@ module.exports = function getSchemaTypes(schema, doc, path) {
           const keys = subdoc ? mpath.get(discriminatorKeyPath, subdoc) || [] : [];
           schemas = Object.keys(discriminators).
             reduce(function(cur, discriminator) {
-              if (doc == null || keys.indexOf(discriminator) !== -1) {
+              const tiedValue = discriminators[discriminator].discriminatorMapping.value;
+              if (doc == null || keys.indexOf(discriminator) !== -1 || keys.indexOf(tiedValue) !== -1) {
                 cur.push(discriminators[discriminator]);
               }
               return cur;

From e9b44e231922897fd940720aaf8b67eb41b96b46 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 18 May 2021 13:16:15 -0400
Subject: [PATCH 2051/2348] chore: release 5.12.10

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 43d374089ab..9a65a763e00 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.12.10 / 2021-05-18
+====================
+ * fix(query): allow setting `defaults` option on result documents from query options #7287 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(populate): handle populating embedded discriminator with custom tiedValue #10231
+ * fix(document): allow passing space-delimited string of `pathsToValidate` to `validate()` and `validateSync()` #10258
+ * fix(model+schema): support `loadClass()` on classes that have `collection` as a static property #10257 #10254 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(SchemaArrayOptions): correct property name #10236
+ * fix(index.d.ts): add any to all query operators to minimize likelihood of "type instantiation is excessively deep" when querying docs with 4-level deep subdocs #10189
+ * fix(index.d.ts): add $parent() in addition to parent() in TS definitions
+ * fix(index.d.ts): correct async iterator return type for QueryCursor #10253 #10252 #10251 [borfig](https://github.com/borfig)
+ * fix(index.d.ts): add `virtualsOnly` parameter to `loadClass()` function signature [IslandRhythms](https://github.com/IslandRhythms)
+ * docs(typescript): add typescript populate docs #10212
+ * docs: switch from AWS to Azure Functions for search #10244
+
 5.12.9 / 2021-05-13
 ===================
  * fix(schema): ensure add() overwrites existing schema paths by default #10208 #10203
diff --git a/package.json b/package.json
index 3f1a8d12f86..093361444fd 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.9",
+  "version": "5.12.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From f07b3fac16dc81ddb89f6520ef9f8601d816bd69 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 18 May 2021 23:52:51 +0200
Subject: [PATCH 2052/2348] test: add more test cases re #10200

---
 test/model.update.test.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/model.update.test.js b/test/model.update.test.js
index e1be08022f0..b0ba39368d9 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -3580,6 +3580,20 @@ describe('model: updateOne: ', function() {
   });
 
   describe('converts dot separated paths to nested structure (gh-10200)', () => {
+    it('works with new Model(...)', () => {
+      const Payment = getPaymentModel();
+      const paymentPOJO = getPaymentWithDotSeparatedPaths();
+      const payment = new Payment(paymentPOJO);
+      assertDocumentStructure(payment.toObject());
+    });
+    it('works with Model.create(...)', () => {
+      return co(function*() {
+        const Payment = getPaymentModel();
+        const paymentPOJO = getPaymentWithDotSeparatedPaths();
+        const payment = yield Payment.create(paymentPOJO);
+        assertDocumentStructure(payment);
+      });
+    });
     it('works with Model.updateOne(...)', () => {
       return co(function*() {
         const User = getPaymentModel();
@@ -3670,6 +3684,10 @@ describe('model: updateOne: ', function() {
         payment.externalServiceResponse.resultDetails.sourceOfFunds,
         { provided: { card: { issuer: 'Big bank corporation' } } }
       );
+      assert.deepEqual(
+        payment.externalServiceResponse.resultDetails.nonExistentField,
+        undefined
+      );
     }
   });
 });
\ No newline at end of file

From caa2c1df4458b653ef0f349da228a746d9cd246f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 18 May 2021 20:06:32 -0400
Subject: [PATCH 2053/2348] chore: remove compiled HTML from master branch re:
 #10263

---
 .gitignore                           |    9 +-
 docs/advanced_schemas.html           |  101 -
 docs/api.html                        | 5061 --------------------------
 docs/api/aggregate.html              |  388 --
 docs/api/aggregationcursor.html      |  105 -
 docs/api/array.html                  |   65 -
 docs/api/connection.html             |  219 --
 docs/api/document.html               |  558 ---
 docs/api/error.html                  |   92 -
 docs/api/model.html                  | 1329 -------
 docs/api/mongoose.html               |  317 --
 docs/api/mongooseerror.html          |   84 -
 docs/api/query.html                  | 1600 --------
 docs/api/querycursor.html            |  106 -
 docs/api/schema.html                 |  426 ---
 docs/api/schematype.html             |  498 ---
 docs/api/singlenestedpath.html       |   78 -
 docs/api/virtualtype.html            |  124 -
 docs/browser.html                    |  140 -
 docs/compatibility.html              |   88 -
 docs/connections.html                |  319 --
 docs/contributing.html               |   55 -
 docs/customschematypes.html          |   99 -
 docs/defaults.html                   |  168 -
 docs/deprecations.html               |  226 --
 docs/discriminators.html             |  352 --
 docs/documents.html                  |  154 -
 docs/faq.html                        |  372 --
 docs/further_reading.html            |  248 --
 docs/geojson.html                    |  188 -
 docs/guide.html                      |  900 -----
 docs/guides.html                     |  101 -
 docs/index.html                      |  128 -
 docs/jest.html                       |  119 -
 docs/lambda.html                     |  122 -
 docs/middleware.html                 |  429 ---
 docs/migrating_to_5.html             |  493 ---
 docs/migration.html                  |   87 -
 docs/models.html                     |  158 -
 docs/plugins.html                    |  124 -
 docs/populate.html                   |  521 ---
 docs/prior.html                      |   53 -
 docs/production.html                 |    9 -
 docs/promises.html                   |  120 -
 docs/queries.html                    |  195 -
 docs/schematypes.html                |  539 ---
 docs/search.html                     |  100 -
 docs/subdocs.html                    |  227 --
 docs/transactions.html               |  217 --
 docs/tutorials/custom-casting.html   |  102 -
 docs/tutorials/dates.html            |  159 -
 docs/tutorials/findoneandupdate.html |  136 -
 docs/tutorials/getters-setters.html  |  181 -
 docs/tutorials/lean.html             |  261 --
 docs/tutorials/query_casting.html    |  140 -
 docs/tutorials/virtuals.html         |  215 --
 docs/validation.html                 |  540 ---
 index.html                           |  166 -
 58 files changed, 7 insertions(+), 20104 deletions(-)
 delete mode 100644 docs/advanced_schemas.html
 delete mode 100644 docs/api.html
 delete mode 100644 docs/api/aggregate.html
 delete mode 100644 docs/api/aggregationcursor.html
 delete mode 100644 docs/api/array.html
 delete mode 100644 docs/api/connection.html
 delete mode 100644 docs/api/document.html
 delete mode 100644 docs/api/error.html
 delete mode 100644 docs/api/model.html
 delete mode 100644 docs/api/mongoose.html
 delete mode 100644 docs/api/mongooseerror.html
 delete mode 100644 docs/api/query.html
 delete mode 100644 docs/api/querycursor.html
 delete mode 100644 docs/api/schema.html
 delete mode 100644 docs/api/schematype.html
 delete mode 100644 docs/api/singlenestedpath.html
 delete mode 100644 docs/api/virtualtype.html
 delete mode 100644 docs/browser.html
 delete mode 100644 docs/compatibility.html
 delete mode 100644 docs/connections.html
 delete mode 100644 docs/contributing.html
 delete mode 100644 docs/customschematypes.html
 delete mode 100644 docs/defaults.html
 delete mode 100644 docs/deprecations.html
 delete mode 100644 docs/discriminators.html
 delete mode 100644 docs/documents.html
 delete mode 100644 docs/faq.html
 delete mode 100644 docs/further_reading.html
 delete mode 100644 docs/geojson.html
 delete mode 100644 docs/guide.html
 delete mode 100644 docs/guides.html
 delete mode 100644 docs/index.html
 delete mode 100644 docs/jest.html
 delete mode 100644 docs/lambda.html
 delete mode 100644 docs/middleware.html
 delete mode 100644 docs/migrating_to_5.html
 delete mode 100644 docs/migration.html
 delete mode 100644 docs/models.html
 delete mode 100644 docs/plugins.html
 delete mode 100644 docs/populate.html
 delete mode 100644 docs/prior.html
 delete mode 100644 docs/production.html
 delete mode 100644 docs/promises.html
 delete mode 100644 docs/queries.html
 delete mode 100644 docs/schematypes.html
 delete mode 100644 docs/search.html
 delete mode 100644 docs/subdocs.html
 delete mode 100644 docs/transactions.html
 delete mode 100644 docs/tutorials/custom-casting.html
 delete mode 100644 docs/tutorials/dates.html
 delete mode 100644 docs/tutorials/findoneandupdate.html
 delete mode 100644 docs/tutorials/getters-setters.html
 delete mode 100644 docs/tutorials/lean.html
 delete mode 100644 docs/tutorials/query_casting.html
 delete mode 100644 docs/tutorials/virtuals.html
 delete mode 100644 docs/validation.html
 delete mode 100644 index.html

diff --git a/.gitignore b/.gitignore
index aaf1108bee1..361b203fffb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -34,8 +34,6 @@ tools/31*
 
 *.key
 
-docs/*.html
-
 # Webpack output
 dist
 test/files/main.js
@@ -43,3 +41,10 @@ test/files/main.js
 package-lock.json
 
 .config*
+
+# Compiled docs
+docs/*.html
+docs/tutorials/*.html
+docs/typescript/*.html
+docs/api/*.html
+index.html
\ No newline at end of file
diff --git a/docs/advanced_schemas.html b/docs/advanced_schemas.html
deleted file mode 100644
index 0407e74c155..00000000000
--- a/docs/advanced_schemas.html
+++ /dev/null
@@ -1,101 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Advanced Schemas</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><ul class="toc"><li><a href="##{block.identifier}">Creating from ES6 Classes Using <code>loadClass()</code></a></li></ul><h2 id="#{block.identifier}"><a href="##{block.identifier}">Creating from ES6 Classes Using <code>loadClass()</code></a></h2><p>Mongoose allows creating schemas from <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes">ES6 classes</a>.
-The <code>loadClass()</code> function lets you pull in methods,
-statics, and virtuals from an ES6 class. A class method maps to a schema
-method, a static method maps to a schema static, and getters/setters map
-to virtuals.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ firstName: <span class="hljs-built_in">String</span>, lastName: <span class="hljs-built_in">String</span> });
-
-<span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">PersonClass</span> </span>{
-  <span class="hljs-comment">// `fullName` becomes a virtual</span>
-  get fullName() {
-    <span class="hljs-keyword">return</span> <span class="hljs-string">`<span class="hljs-subst">${this.firstName}</span> <span class="hljs-subst">${this.lastName}</span>`</span>;
-  }
-
-  set fullName(v) {
-    <span class="hljs-keyword">const</span> firstSpace = v.indexOf(<span class="hljs-string">' '</span>);
-    <span class="hljs-keyword">this</span>.firstName = v.split(<span class="hljs-string">' '</span>)[<span class="hljs-number">0</span>];
-    <span class="hljs-keyword">this</span>.lastName = firstSpace === <span class="hljs-number">-1</span> ? <span class="hljs-string">''</span> : v.substr(firstSpace + <span class="hljs-number">1</span>);
-  }
-
-  <span class="hljs-comment">// `getFullName()` becomes a document method</span>
-  getFullName() {
-    <span class="hljs-keyword">return</span> <span class="hljs-string">`<span class="hljs-subst">${this.firstName}</span> <span class="hljs-subst">${this.lastName}</span>`</span>;
-  }
-
-  <span class="hljs-comment">// `findByFullName()` becomes a static</span>
-  static findByFullName(name) {
-    <span class="hljs-keyword">const</span> firstSpace = name.indexOf(<span class="hljs-string">' '</span>);
-    <span class="hljs-keyword">const</span> firstName = name.split(<span class="hljs-string">' '</span>)[<span class="hljs-number">0</span>];
-    <span class="hljs-keyword">const</span> lastName = firstSpace === <span class="hljs-number">-1</span> ? <span class="hljs-string">''</span> : name.substr(firstSpace + <span class="hljs-number">1</span>);
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.findOne({ firstName, lastName });
-  }
-}
-
-schema.loadClass(PersonClass);
-<span class="hljs-keyword">var</span> Person = db.model(<span class="hljs-string">'Person'</span>, schema);
-
-Person.create({ firstName: <span class="hljs-string">'Jon'</span>, lastName: <span class="hljs-string">'Snow'</span> }).
-  then(doc =&gt; {
-    assert.equal(doc.fullName, <span class="hljs-string">'Jon Snow'</span>);
-    doc.fullName = <span class="hljs-string">'Jon Stark'</span>;
-    assert.equal(doc.firstName, <span class="hljs-string">'Jon'</span>);
-    assert.equal(doc.lastName, <span class="hljs-string">'Stark'</span>);
-    <span class="hljs-keyword">return</span> Person.findByFullName(<span class="hljs-string">'Jon Snow'</span>);
-  }).
-  then(doc =&gt; {
-    assert.equal(doc.fullName, <span class="hljs-string">'Jon Snow'</span>);
-  });</code></pre>
-<div class="suffix"></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api.html b/docs/api.html
deleted file mode 100644
index c1050e23c3a..00000000000
--- a/docs/api.html
+++ /dev/null
@@ -1,5061 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: API docs</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>API Docs</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="./api/Mongoose.html">Mongoose</a></div><ul class="nav-item-sub"><li><a href="./api/mongoose.html#mongoose_Mongoose">Mongoose()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Aggregate">Mongoose.prototype.Aggregate()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-CastError">Mongoose.prototype.CastError()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Collection">Mongoose.prototype.Collection()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Connection">Mongoose.prototype.Connection()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Decimal128">Mongoose.prototype.Decimal128</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Document">Mongoose.prototype.Document()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-DocumentProvider">Mongoose.prototype.DocumentProvider()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Error">Mongoose.prototype.Error()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Mixed">Mongoose.prototype.Mixed</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Model">Mongoose.prototype.Model()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Mongoose">Mongoose.prototype.Mongoose()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Number">Mongoose.prototype.Number</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-ObjectId">Mongoose.prototype.ObjectId</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Promise">Mongoose.prototype.Promise</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-PromiseProvider">Mongoose.prototype.PromiseProvider()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Query">Mongoose.prototype.Query()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-STATES">Mongoose.prototype.STATES</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Schema">Mongoose.prototype.Schema()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-SchemaType">Mongoose.prototype.SchemaType()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-SchemaTypes">Mongoose.prototype.SchemaTypes</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-Types">Mongoose.prototype.Types</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-VirtualType">Mongoose.prototype.VirtualType()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-connect">Mongoose.prototype.connect()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-connection">Mongoose.prototype.connection</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-connections">Mongoose.prototype.connections</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-createConnection">Mongoose.prototype.createConnection()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-deleteModel">Mongoose.prototype.deleteModel()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-disconnect">Mongoose.prototype.disconnect()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-driver">Mongoose.prototype.driver</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-get">Mongoose.prototype.get()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-model">Mongoose.prototype.model()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-modelNames">Mongoose.prototype.modelNames()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-mongo">Mongoose.prototype.mongo</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-mquery">Mongoose.prototype.mquery</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-now">Mongoose.prototype.now()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-plugin">Mongoose.prototype.plugin()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-pluralize">Mongoose.prototype.pluralize()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-set">Mongoose.prototype.set()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-startSession">Mongoose.prototype.startSession()</a></li><li><a href="./api/mongoose.html#mongoose_Mongoose-version">Mongoose.prototype.version</a></li></ul></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="./api/Schema.html">Schema</a></div><ul class="nav-item-sub"><li><a href="./api/schema.html#schema_Schema">Schema()</a></li><li><a href="./api/schema.html#schema_Schema.Types">Schema.Types</a></li><li><a href="./api/schema.html#schema_Schema-indexTypes">Schema.indexTypes</a></li><li><a href="./api/schema.html#schema_Schema-add">Schema.prototype.add()</a></li><li><a href="./api/schema.html#schema_Schema-childSchemas">Schema.prototype.childSchemas</a></li><li><a href="./api/schema.html#schema_Schema-clone">Schema.prototype.clone()</a></li><li><a href="./api/schema.html#schema_Schema-eachPath">Schema.prototype.eachPath()</a></li><li><a href="./api/schema.html#schema_Schema-get">Schema.prototype.get()</a></li><li><a href="./api/schema.html#schema_Schema-index">Schema.prototype.index()</a></li><li><a href="./api/schema.html#schema_Schema-indexes">Schema.prototype.indexes()</a></li><li><a href="./api/schema.html#schema_Schema-loadClass">Schema.prototype.loadClass()</a></li><li><a href="./api/schema.html#schema_Schema-method">Schema.prototype.method()</a></li><li><a href="./api/schema.html#schema_Schema-obj">Schema.prototype.obj</a></li><li><a href="./api/schema.html#schema_Schema-path">Schema.prototype.path()</a></li><li><a href="./api/schema.html#schema_Schema-pathType">Schema.prototype.pathType()</a></li><li><a href="./api/schema.html#schema_Schema-plugin">Schema.prototype.plugin()</a></li><li><a href="./api/schema.html#schema_Schema-post">Schema.prototype.post()</a></li><li><a href="./api/schema.html#schema_Schema-pre">Schema.prototype.pre()</a></li><li><a href="./api/schema.html#schema_Schema-queue">Schema.prototype.queue()</a></li><li><a href="./api/schema.html#schema_Schema-remove">Schema.prototype.remove()</a></li><li><a href="./api/schema.html#schema_Schema-requiredPaths">Schema.prototype.requiredPaths()</a></li><li><a href="./api/schema.html#schema_Schema-set">Schema.prototype.set()</a></li><li><a href="./api/schema.html#schema_Schema-static">Schema.prototype.static()</a></li><li><a href="./api/schema.html#schema_Schema-virtual">Schema.prototype.virtual()</a></li><li><a href="./api/schema.html#schema_Schema-virtualpath">Schema.prototype.virtualpath()</a></li><li><a href="./api/schema.html#schema_Schema.reserved">Schema.reserved</a></li></ul></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="./api/Connection.html">Connection</a></div><ul class="nav-item-sub"><li><a href="./api/connection.html#connection_Connection">Connection()</a></li><li><a href="./api/connection.html#connection_Connection-close">Connection.prototype.close()</a></li><li><a href="./api/connection.html#connection_Connection-collection">Connection.prototype.collection()</a></li><li><a href="./api/connection.html#connection_Connection-collections">Connection.prototype.collections</a></li><li><a href="./api/connection.html#connection_Connection-config">Connection.prototype.config</a></li><li><a href="./api/connection.html#connection_Connection-createCollection">Connection.prototype.createCollection()</a></li><li><a href="./api/connection.html#connection_Connection-db">Connection.prototype.db</a></li><li><a href="./api/connection.html#connection_Connection-deleteModel">Connection.prototype.deleteModel()</a></li><li><a href="./api/connection.html#connection_Connection-dropCollection">Connection.prototype.dropCollection()</a></li><li><a href="./api/connection.html#connection_Connection-dropDatabase">Connection.prototype.dropDatabase()</a></li><li><a href="./api/connection.html#connection_Connection-get">Connection.prototype.get()</a></li><li><a href="./api/connection.html#connection_Connection-host">Connection.prototype.host</a></li><li><a href="./api/connection.html#connection_Connection-model">Connection.prototype.model()</a></li><li><a href="./api/connection.html#connection_Connection-modelNames">Connection.prototype.modelNames()</a></li><li><a href="./api/connection.html#connection_Connection-name">Connection.prototype.name</a></li><li><a href="./api/connection.html#connection_Connection-openUri">Connection.prototype.openUri()</a></li><li><a href="./api/connection.html#connection_Connection-pass">Connection.prototype.pass</a></li><li><a href="./api/connection.html#connection_Connection-plugin">Connection.prototype.plugin()</a></li><li><a href="./api/connection.html#connection_Connection-plugins">Connection.prototype.plugins</a></li><li><a href="./api/connection.html#connection_Connection-port">Connection.prototype.port</a></li><li><a href="./api/connection.html#connection_Connection-readyState">Connection.prototype.readyState</a></li><li><a href="./api/connection.html#connection_Connection-set">Connection.prototype.set()</a></li><li><a href="./api/connection.html#connection_Connection-startSession">Connection.prototype.startSession()</a></li><li><a href="./api/connection.html#connection_Connection-useDb">Connection.prototype.useDb()</a></li><li><a href="./api/connection.html#connection_Connection-user">Connection.prototype.user</a></li></ul></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="./api/Document.html">Document</a></div><ul class="nav-item-sub"><li><a href="./api/document.html#document_Document-$ignore">Document.prototype.$ignore()</a></li><li><a href="./api/document.html#document_Document-$isDefault">Document.prototype.$isDefault()</a></li><li><a href="./api/document.html#document_Document-$isDeleted">Document.prototype.$isDeleted()</a></li><li><a href="./api/document.html#document_Document-$isEmpty">Document.prototype.$isEmpty()</a></li><li><a href="./api/document.html#document_Document-$locals">Document.prototype.$locals</a></li><li><a href="./api/document.html#document_Document-$markValid">Document.prototype.$markValid()</a></li><li><a href="./api/document.html#document_Document-$session">Document.prototype.$session()</a></li><li><a href="./api/document.html#document_Document-$set">Document.prototype.$set()</a></li><li><a href="./api/document.html#document_Document-depopulate">Document.prototype.depopulate()</a></li><li><a href="./api/document.html#document_Document-directModifiedPaths">Document.prototype.directModifiedPaths()</a></li><li><a href="./api/document.html#document_Document-equals">Document.prototype.equals()</a></li><li><a href="./api/document.html#document_Document-errors">Document.prototype.errors</a></li><li><a href="./api/document.html#document_Document-execPopulate">Document.prototype.execPopulate()</a></li><li><a href="./api/document.html#document_Document-get">Document.prototype.get()</a></li><li><a href="./api/document.html#document_Document-id">Document.prototype.id</a></li><li><a href="./api/document.html#document_Document-init">Document.prototype.init()</a></li><li><a href="./api/document.html#document_Document-inspect">Document.prototype.inspect()</a></li><li><a href="./api/document.html#document_Document-invalidate">Document.prototype.invalidate()</a></li><li><a href="./api/document.html#document_Document-isDirectModified">Document.prototype.isDirectModified()</a></li><li><a href="./api/document.html#document_Document-isDirectSelected">Document.prototype.isDirectSelected()</a></li><li><a href="./api/document.html#document_Document-isInit">Document.prototype.isInit()</a></li><li><a href="./api/document.html#document_Document-isModified">Document.prototype.isModified()</a></li><li><a href="./api/document.html#document_Document-isNew">Document.prototype.isNew</a></li><li><a href="./api/document.html#document_Document-isSelected">Document.prototype.isSelected()</a></li><li><a href="./api/document.html#document_Document-markModified">Document.prototype.markModified()</a></li><li><a href="./api/document.html#document_Document-modifiedPaths">Document.prototype.modifiedPaths()</a></li><li><a href="./api/document.html#document_Document-overwrite">Document.prototype.overwrite()</a></li><li><a href="./api/document.html#document_Document-populate">Document.prototype.populate()</a></li><li><a href="./api/document.html#document_Document-populated">Document.prototype.populated()</a></li><li><a href="./api/document.html#document_Document-replaceOne">Document.prototype.replaceOne()</a></li><li><a href="./api/document.html#document_Document-save">Document.prototype.save()</a></li><li><a href="./api/document.html#document_Document-schema">Document.prototype.schema</a></li><li><a href="./api/document.html#document_Document-set">Document.prototype.set()</a></li><li><a href="./api/document.html#document_Document-toJSON">Document.prototype.toJSON()</a></li><li><a href="./api/document.html#document_Document-toObject">Document.prototype.toObject()</a></li><li><a href="./api/document.html#document_Document-toString">Document.prototype.toString()</a></li><li><a href="./api/document.html#document_Document-unmarkModified">Document.prototype.unmarkModified()</a></li><li><a href="./api/document.html#document_Document-update">Document.prototype.update()</a></li><li><a href="./api/document.html#document_Document-updateOne">Document.prototype.updateOne()</a></li><li><a href="./api/document.html#document_Document-validate">Document.prototype.validate()</a></li><li><a href="./api/document.html#document_Document-validateSync">Document.prototype.validateSync()</a></li></ul></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="./api/Model.html">Model</a></div><ul class="nav-item-sub"><li><a href="./api/model.html#model_Model">Model()</a></li><li><a href="./api/model.html#model_Model.aggregate">Model.aggregate()</a></li><li><a href="./api/model.html#model_Model.bulkWrite">Model.bulkWrite()</a></li><li><a href="./api/model.html#model_Model.count">Model.count()</a></li><li><a href="./api/model.html#model_Model.countDocuments">Model.countDocuments()</a></li><li><a href="./api/model.html#model_Model.create">Model.create()</a></li><li><a href="./api/model.html#model_Model.createCollection">Model.createCollection()</a></li><li><a href="./api/model.html#model_Model.createIndexes">Model.createIndexes()</a></li><li><a href="./api/model.html#model_Model.deleteMany">Model.deleteMany()</a></li><li><a href="./api/model.html#model_Model.deleteOne">Model.deleteOne()</a></li><li><a href="./api/model.html#model_Model.discriminator">Model.discriminator()</a></li><li><a href="./api/model.html#model_Model.distinct">Model.distinct()</a></li><li><a href="./api/model.html#model_Model.ensureIndexes">Model.ensureIndexes()</a></li><li><a href="./api/model.html#model_Model.estimatedDocumentCount">Model.estimatedDocumentCount()</a></li><li><a href="./api/model.html#model_Model-events">Model.events</a></li><li><a href="./api/model.html#model_Model.exists">Model.exists()</a></li><li><a href="./api/model.html#model_Model.find">Model.find()</a></li><li><a href="./api/model.html#model_Model.findById">Model.findById()</a></li><li><a href="./api/model.html#model_Model.findByIdAndDelete">Model.findByIdAndDelete()</a></li><li><a href="./api/model.html#model_Model.findByIdAndRemove">Model.findByIdAndRemove()</a></li><li><a href="./api/model.html#model_Model.findByIdAndUpdate">Model.findByIdAndUpdate()</a></li><li><a href="./api/model.html#model_Model.findOne">Model.findOne()</a></li><li><a href="./api/model.html#model_Model.findOneAndDelete">Model.findOneAndDelete()</a></li><li><a href="./api/model.html#model_Model.findOneAndRemove">Model.findOneAndRemove()</a></li><li><a href="./api/model.html#model_Model.findOneAndReplace">Model.findOneAndReplace()</a></li><li><a href="./api/model.html#model_Model.findOneAndUpdate">Model.findOneAndUpdate()</a></li><li><a href="./api/model.html#model_Model.geoSearch">Model.geoSearch()</a></li><li><a href="./api/model.html#model_Model.hydrate">Model.hydrate()</a></li><li><a href="./api/model.html#model_Model.init">Model.init()</a></li><li><a href="./api/model.html#model_Model.insertMany">Model.insertMany()</a></li><li><a href="./api/model.html#model_Model.listIndexes">Model.listIndexes()</a></li><li><a href="./api/model.html#model_Model.mapReduce">Model.mapReduce()</a></li><li><a href="./api/model.html#model_Model.populate">Model.populate()</a></li><li><a href="./api/model.html#model_Model-$where">Model.prototype.$where</a></li><li><a href="./api/model.html#model_Model-$where">Model.prototype.$where()</a></li><li><a href="./api/model.html#model_Model-base">Model.prototype.base</a></li><li><a href="./api/model.html#model_Model-baseModelName">Model.prototype.baseModelName</a></li><li><a href="./api/model.html#model_Model-collection">Model.prototype.collection</a></li><li><a href="./api/model.html#model_Model-db">Model.prototype.db</a></li><li><a href="./api/model.html#model_Model-delete">Model.prototype.delete</a></li><li><a href="./api/model.html#model_Model-deleteOne">Model.prototype.deleteOne()</a></li><li><a href="./api/model.html#model_Model-discriminators">Model.prototype.discriminators</a></li><li><a href="./api/model.html#model_Model-increment">Model.prototype.increment()</a></li><li><a href="./api/model.html#model_Model-model">Model.prototype.model()</a></li><li><a href="./api/model.html#model_Model-modelName">Model.prototype.modelName</a></li><li><a href="./api/model.html#model_Model-remove">Model.prototype.remove()</a></li><li><a href="./api/model.html#model_Model-save">Model.prototype.save()</a></li><li><a href="./api/model.html#model_Model-schema">Model.prototype.schema</a></li><li><a href="./api/model.html#model_Model.remove">Model.remove()</a></li><li><a href="./api/model.html#model_Model.replaceOne">Model.replaceOne()</a></li><li><a href="./api/model.html#model_Model.startSession">Model.startSession()</a></li><li><a href="./api/model.html#model_Model.syncIndexes">Model.syncIndexes()</a></li><li><a href="./api/model.html#model_Model.translateAliases">Model.translateAliases()</a></li><li><a href="./api/model.html#model_Model.update">Model.update()</a></li><li><a href="./api/model.html#model_Model.updateMany">Model.updateMany()</a></li><li><a href="./api/model.html#model_Model.updateOne">Model.updateOne()</a></li><li><a href="./api/model.html#model_Model.watch">Model.watch()</a></li><li><a href="./api/model.html#model_Model.where">Model.where()</a></li><li><a href="./api/model.html#model_Model.inspect">function Object() { [native code] }.prototype.inspect()</a></li></ul></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="./api/Query.html">Query</a></div><ul class="nav-item-sub"><li><a href="./api/query.html#query_Query">Query()</a></li><li><a href="./api/query.html#query_Query-$where">Query.prototype.$where()</a></li><li><a href="./api/query.html#query_Query-Symbol.asyncIterator">Query.prototype.Symbol.asyncIterator()</a></li><li><a href="./api/query.html#query_Query-all">Query.prototype.all()</a></li><li><a href="./api/query.html#query_Query-and">Query.prototype.and()</a></li><li><a href="./api/query.html#query_Query-batchSize">Query.prototype.batchSize()</a></li><li><a href="./api/query.html#query_Query-box">Query.prototype.box()</a></li><li><a href="./api/query.html#query_Query-cast">Query.prototype.cast()</a></li><li><a href="./api/query.html#query_Query-catch">Query.prototype.catch()</a></li><li><a href="./api/query.html#query_Query-center">Query.prototype.center()</a></li><li><a href="./api/query.html#query_Query-centerSphere">Query.prototype.centerSphere()</a></li><li><a href="./api/query.html#query_Query-circle">Query.prototype.circle()</a></li><li><a href="./api/query.html#query_Query-collation">Query.prototype.collation()</a></li><li><a href="./api/query.html#query_Query-comment">Query.prototype.comment()</a></li><li><a href="./api/query.html#query_Query-count">Query.prototype.count()</a></li><li><a href="./api/query.html#query_Query-countDocuments">Query.prototype.countDocuments()</a></li><li><a href="./api/query.html#query_Query-cursor">Query.prototype.cursor()</a></li><li><a href="./api/query.html#query_Query-deleteMany">Query.prototype.deleteMany()</a></li><li><a href="./api/query.html#query_Query-deleteOne">Query.prototype.deleteOne()</a></li><li><a href="./api/query.html#query_Query-distinct">Query.prototype.distinct()</a></li><li><a href="./api/query.html#query_Query-elemMatch">Query.prototype.elemMatch()</a></li><li><a href="./api/query.html#query_Query-equals">Query.prototype.equals()</a></li><li><a href="./api/query.html#query_Query-error">Query.prototype.error()</a></li><li><a href="./api/query.html#query_Query-estimatedDocumentCount">Query.prototype.estimatedDocumentCount()</a></li><li><a href="./api/query.html#query_Query-exec">Query.prototype.exec()</a></li><li><a href="./api/query.html#query_Query-exists">Query.prototype.exists()</a></li><li><a href="./api/query.html#query_Query-explain">Query.prototype.explain()</a></li><li><a href="./api/query.html#query_Query-find">Query.prototype.find()</a></li><li><a href="./api/query.html#query_Query-findOne">Query.prototype.findOne()</a></li><li><a href="./api/query.html#query_Query-findOneAndDelete">Query.prototype.findOneAndDelete()</a></li><li><a href="./api/query.html#query_Query-findOneAndRemove">Query.prototype.findOneAndRemove()</a></li><li><a href="./api/query.html#query_Query-findOneAndReplace">Query.prototype.findOneAndReplace()</a></li><li><a href="./api/query.html#query_Query-findOneAndUpdate">Query.prototype.findOneAndUpdate()</a></li><li><a href="./api/query.html#query_Query-geometry">Query.prototype.geometry()</a></li><li><a href="./api/query.html#query_Query-getFilter">Query.prototype.getFilter()</a></li><li><a href="./api/query.html#query_Query-getOptions">Query.prototype.getOptions()</a></li><li><a href="./api/query.html#query_Query-getPopulatedPaths">Query.prototype.getPopulatedPaths()</a></li><li><a href="./api/query.html#query_Query-getQuery">Query.prototype.getQuery()</a></li><li><a href="./api/query.html#query_Query-getUpdate">Query.prototype.getUpdate()</a></li><li><a href="./api/query.html#query_Query-gt">Query.prototype.gt()</a></li><li><a href="./api/query.html#query_Query-gte">Query.prototype.gte()</a></li><li><a href="./api/query.html#query_Query-hint">Query.prototype.hint()</a></li><li><a href="./api/query.html#query_Query-in">Query.prototype.in()</a></li><li><a href="./api/query.html#query_Query-intersects">Query.prototype.intersects()</a></li><li><a href="./api/query.html#query_Query-j">Query.prototype.j()</a></li><li><a href="./api/query.html#query_Query-lean">Query.prototype.lean()</a></li><li><a href="./api/query.html#query_Query-limit">Query.prototype.limit()</a></li><li><a href="./api/query.html#query_Query-lt">Query.prototype.lt()</a></li><li><a href="./api/query.html#query_Query-lte">Query.prototype.lte()</a></li><li><a href="./api/query.html#query_Query-map">Query.prototype.map()</a></li><li><a href="./api/query.html#query_Query-maxDistance">Query.prototype.maxDistance()</a></li><li><a href="./api/query.html#query_Query-maxScan">Query.prototype.maxScan()</a></li><li><a href="./api/query.html#query_Query-maxTimeMS">Query.prototype.maxTimeMS()</a></li><li><a href="./api/query.html#query_Query-maxscan">Query.prototype.maxscan()</a></li><li><a href="./api/query.html#query_Query-merge">Query.prototype.merge()</a></li><li><a href="./api/query.html#query_Query-mod">Query.prototype.mod()</a></li><li><a href="./api/query.html#query_Query-mongooseOptions">Query.prototype.mongooseOptions()</a></li><li><a href="./api/query.html#query_Query-ne">Query.prototype.ne()</a></li><li><a href="./api/query.html#query_Query-near">Query.prototype.near()</a></li><li><a href="./api/query.html#query_Query-nearSphere">Query.prototype.nearSphere()</a></li><li><a href="./api/query.html#query_Query-nin">Query.prototype.nin()</a></li><li><a href="./api/query.html#query_Query-nor">Query.prototype.nor()</a></li><li><a href="./api/query.html#query_Query-or">Query.prototype.or()</a></li><li><a href="./api/query.html#query_Query-orFail">Query.prototype.orFail()</a></li><li><a href="./api/query.html#query_Query-polygon">Query.prototype.polygon()</a></li><li><a href="./api/query.html#query_Query-populate">Query.prototype.populate()</a></li><li><a href="./api/query.html#query_Query-projection">Query.prototype.projection()</a></li><li><a href="./api/query.html#query_Query-read">Query.prototype.read()</a></li><li><a href="./api/query.html#query_Query-readConcern">Query.prototype.readConcern()</a></li><li><a href="./api/query.html#query_Query-regex">Query.prototype.regex()</a></li><li><a href="./api/query.html#query_Query-remove">Query.prototype.remove()</a></li><li><a href="./api/query.html#query_Query-replaceOne">Query.prototype.replaceOne()</a></li><li><a href="./api/query.html#query_Query-select">Query.prototype.select()</a></li><li><a href="./api/query.html#query_Query-selected">Query.prototype.selected()</a></li><li><a href="./api/query.html#query_Query-selectedExclusively">Query.prototype.selectedExclusively()</a></li><li><a href="./api/query.html#query_Query-selectedInclusively">Query.prototype.selectedInclusively()</a></li><li><a href="./api/query.html#query_Query-session">Query.prototype.session()</a></li><li><a href="./api/query.html#query_Query-set">Query.prototype.set()</a></li><li><a href="./api/query.html#query_Query-setOptions">Query.prototype.setOptions()</a></li><li><a href="./api/query.html#query_Query-setQuery">Query.prototype.setQuery()</a></li><li><a href="./api/query.html#query_Query-setUpdate">Query.prototype.setUpdate()</a></li><li><a href="./api/query.html#query_Query-size">Query.prototype.size()</a></li><li><a href="./api/query.html#query_Query-skip">Query.prototype.skip()</a></li><li><a href="./api/query.html#query_Query-slaveOk">Query.prototype.slaveOk()</a></li><li><a href="./api/query.html#query_Query-slice">Query.prototype.slice()</a></li><li><a href="./api/query.html#query_Query-snapshot">Query.prototype.snapshot()</a></li><li><a href="./api/query.html#query_Query-sort">Query.prototype.sort()</a></li><li><a href="./api/query.html#query_Query-tailable">Query.prototype.tailable()</a></li><li><a href="./api/query.html#query_Query-then">Query.prototype.then()</a></li><li><a href="./api/query.html#query_Query-toConstructor">Query.prototype.toConstructor()</a></li><li><a href="./api/query.html#query_Query-update">Query.prototype.update()</a></li><li><a href="./api/query.html#query_Query-updateMany">Query.prototype.updateMany()</a></li><li><a href="./api/query.html#query_Query-updateOne">Query.prototype.updateOne()</a></li><li><a href="./api/query.html#query_Query-use$geoWithin">Query.prototype.use$geoWithin</a></li><li><a href="./api/query.html#query_Query-w">Query.prototype.w()</a></li><li><a href="./api/query.html#query_Query-where">Query.prototype.where()</a></li><li><a href="./api/query.html#query_Query-within">Query.prototype.within()</a></li><li><a href="./api/query.html#query_Query-wtimeout">Query.prototype.wtimeout()</a></li></ul></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="./api/QueryCursor.html">QueryCursor</a></div><ul class="nav-item-sub"><li><a href="./api/querycursor.html#querycursor_QueryCursor">QueryCursor()</a></li><li><a href="./api/querycursor.html#querycursor_QueryCursor-addCursorFlag">QueryCursor.prototype.addCursorFlag()</a></li><li><a href="./api/querycursor.html#querycursor_QueryCursor-close">QueryCursor.prototype.close()</a></li><li><a href="./api/querycursor.html#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></li><li><a href="./api/querycursor.html#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></li><li><a href="./api/querycursor.html#querycursor_QueryCursor-next">QueryCursor.prototype.next()</a></li></ul></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="./api/Aggregate.html">Aggregate</a></div><ul class="nav-item-sub"><li><a href="./api/aggregate.html#aggregate_Aggregate">Aggregate()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-Symbol.asyncIterator">Aggregate.prototype.Symbol.asyncIterator()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-addCursorFlag">Aggregate.prototype.addCursorFlag</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-addFields">Aggregate.prototype.addFields()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-allowDiskUse">Aggregate.prototype.allowDiskUse()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-append">Aggregate.prototype.append()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-catch">Aggregate.prototype.catch()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-collation">Aggregate.prototype.collation()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-count">Aggregate.prototype.count()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-cursor">Aggregate.prototype.cursor()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-exec">Aggregate.prototype.exec()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-explain">Aggregate.prototype.explain()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-facet">Aggregate.prototype.facet()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-graphLookup">Aggregate.prototype.graphLookup()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-group">Aggregate.prototype.group()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-hint">Aggregate.prototype.hint()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-limit">Aggregate.prototype.limit()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-lookup">Aggregate.prototype.lookup()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-match">Aggregate.prototype.match()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-model">Aggregate.prototype.model()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-near">Aggregate.prototype.near()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-option">Aggregate.prototype.option()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-options">Aggregate.prototype.options</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-pipeline">Aggregate.prototype.pipeline()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-project">Aggregate.prototype.project()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-read">Aggregate.prototype.read()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-readConcern">Aggregate.prototype.readConcern()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-redact">Aggregate.prototype.redact()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-replaceRoot">Aggregate.prototype.replaceRoot()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-sample">Aggregate.prototype.sample()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-session">Aggregate.prototype.session()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-skip">Aggregate.prototype.skip()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-sort">Aggregate.prototype.sort()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-sortByCount">Aggregate.prototype.sortByCount()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-then">Aggregate.prototype.then()</a></li><li><a href="./api/aggregate.html#aggregate_Aggregate-unwind">Aggregate.prototype.unwind()</a></li></ul></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="./api/AggregationCursor.html">AggregationCursor</a></div><ul class="nav-item-sub"><li><a href="./api/aggregationcursor.html#aggregationcursor_AggregationCursor">AggregationCursor()</a></li><li><a href="./api/aggregationcursor.html#aggregationcursor_AggregationCursor-addCursorFlag">AggregationCursor.prototype.addCursorFlag()</a></li><li><a href="./api/aggregationcursor.html#aggregationcursor_AggregationCursor-close">AggregationCursor.prototype.close()</a></li><li><a href="./api/aggregationcursor.html#aggregationcursor_AggregationCursor-eachAsync">AggregationCursor.prototype.eachAsync()</a></li><li><a href="./api/aggregationcursor.html#aggregationcursor_AggregationCursor-map">AggregationCursor.prototype.map()</a></li><li><a href="./api/aggregationcursor.html#aggregationcursor_AggregationCursor-next">AggregationCursor.prototype.next()</a></li></ul></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="./api/Schematype.html">Schematype</a></div><ul class="nav-item-sub"><li><a href="./api/schematype.html#schematype_SchemaType">SchemaType()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-cast">SchemaType.cast()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-checkRequired">SchemaType.checkRequired()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-get">SchemaType.get()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-default">SchemaType.prototype.default()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-get">SchemaType.prototype.get()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-immutable">SchemaType.prototype.immutable()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-index">SchemaType.prototype.index()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-ref">SchemaType.prototype.ref()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-required">SchemaType.prototype.required()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-select">SchemaType.prototype.select()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-set">SchemaType.prototype.set()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-sparse">SchemaType.prototype.sparse()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-text">SchemaType.prototype.text()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-unique">SchemaType.prototype.unique()</a></li><li><a href="./api/schematype.html#schematype_SchemaType-validate">SchemaType.prototype.validate()</a></li></ul></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="./api/Virtualtype.html">Virtualtype</a></div><ul class="nav-item-sub"><li><a href="./api/virtualtype.html#virtualtype_VirtualType">VirtualType()</a></li><li><a href="./api/virtualtype.html#virtualtype_VirtualType-applyGetters">VirtualType.prototype.applyGetters()</a></li><li><a href="./api/virtualtype.html#virtualtype_VirtualType-applySetters">VirtualType.prototype.applySetters()</a></li><li><a href="./api/virtualtype.html#virtualtype_VirtualType-get">VirtualType.prototype.get()</a></li><li><a href="./api/virtualtype.html#virtualtype_VirtualType-set">VirtualType.prototype.set()</a></li></ul></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="./api/Error.html">Error</a></div><ul class="nav-item-sub"><li><a href="./api/error.html#mongooseerror_MongooseError">Error()</a></li><li><a href="./api/error.html#error_Error-CastError">Error.CastError</a></li><li><a href="./api/error.html#error_Error-DivergentArrayError">Error.DivergentArrayError</a></li><li><a href="./api/error.html#error_Error-DocumentNotFoundError">Error.DocumentNotFoundError</a></li><li><a href="./api/error.html#error_Error-MissingSchemaError">Error.MissingSchemaError</a></li><li><a href="./api/error.html#error_Error-OverwriteModelError">Error.OverwriteModelError</a></li><li><a href="./api/error.html#error_Error-ParallelSaveError">Error.ParallelSaveError</a></li><li><a href="./api/error.html#error_Error-ValidationError">Error.ValidationError</a></li><li><a href="./api/error.html#error_Error-ValidatorError">Error.ValidatorError</a></li><li><a href="./api/error.html#error_Error-VersionError">Error.VersionError</a></li><li><a href="./api/error.html#error_Error-messages">Error.messages</a></li><li><a href="./api/error.html#error_Error-name">Error.prototype.name</a></li></ul></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="./api/Array.html">Array</a></div><ul class="nav-item-sub"></ul></div></div></div><hr class="separate-api"><h2 class="item-header" id="Mongoose"><a href="#Mongoose">Mongoose</a></h2><ul><li><a href="#mongoose_Mongoose">Mongoose()</a></li><li><a href="#mongoose_Mongoose-Aggregate">Mongoose.prototype.Aggregate()</a></li><li><a href="#mongoose_Mongoose-CastError">Mongoose.prototype.CastError()</a></li><li><a href="#mongoose_Mongoose-Collection">Mongoose.prototype.Collection()</a></li><li><a href="#mongoose_Mongoose-Connection">Mongoose.prototype.Connection()</a></li><li><a href="#mongoose_Mongoose-Decimal128">Mongoose.prototype.Decimal128</a></li><li><a href="#mongoose_Mongoose-Document">Mongoose.prototype.Document()</a></li><li><a href="#mongoose_Mongoose-DocumentProvider">Mongoose.prototype.DocumentProvider()</a></li><li><a href="#mongoose_Mongoose-Error">Mongoose.prototype.Error()</a></li><li><a href="#mongoose_Mongoose-Mixed">Mongoose.prototype.Mixed</a></li><li><a href="#mongoose_Mongoose-Model">Mongoose.prototype.Model()</a></li><li><a href="#mongoose_Mongoose-Mongoose">Mongoose.prototype.Mongoose()</a></li><li><a href="#mongoose_Mongoose-Number">Mongoose.prototype.Number</a></li><li><a href="#mongoose_Mongoose-ObjectId">Mongoose.prototype.ObjectId</a></li><li><a href="#mongoose_Mongoose-Promise">Mongoose.prototype.Promise</a></li><li><a href="#mongoose_Mongoose-PromiseProvider">Mongoose.prototype.PromiseProvider()</a></li><li><a href="#mongoose_Mongoose-Query">Mongoose.prototype.Query()</a></li><li><a href="#mongoose_Mongoose-STATES">Mongoose.prototype.STATES</a></li><li><a href="#mongoose_Mongoose-Schema">Mongoose.prototype.Schema()</a></li><li><a href="#mongoose_Mongoose-SchemaType">Mongoose.prototype.SchemaType()</a></li><li><a href="#mongoose_Mongoose-SchemaTypes">Mongoose.prototype.SchemaTypes</a></li><li><a href="#mongoose_Mongoose-Types">Mongoose.prototype.Types</a></li><li><a href="#mongoose_Mongoose-VirtualType">Mongoose.prototype.VirtualType()</a></li><li><a href="#mongoose_Mongoose-connect">Mongoose.prototype.connect()</a></li><li><a href="#mongoose_Mongoose-connection">Mongoose.prototype.connection</a></li><li><a href="#mongoose_Mongoose-connections">Mongoose.prototype.connections</a></li><li><a href="#mongoose_Mongoose-createConnection">Mongoose.prototype.createConnection()</a></li><li><a href="#mongoose_Mongoose-deleteModel">Mongoose.prototype.deleteModel()</a></li><li><a href="#mongoose_Mongoose-disconnect">Mongoose.prototype.disconnect()</a></li><li><a href="#mongoose_Mongoose-driver">Mongoose.prototype.driver</a></li><li><a href="#mongoose_Mongoose-get">Mongoose.prototype.get()</a></li><li><a href="#mongoose_Mongoose-model">Mongoose.prototype.model()</a></li><li><a href="#mongoose_Mongoose-modelNames">Mongoose.prototype.modelNames()</a></li><li><a href="#mongoose_Mongoose-mongo">Mongoose.prototype.mongo</a></li><li><a href="#mongoose_Mongoose-mquery">Mongoose.prototype.mquery</a></li><li><a href="#mongoose_Mongoose-now">Mongoose.prototype.now()</a></li><li><a href="#mongoose_Mongoose-plugin">Mongoose.prototype.plugin()</a></li><li><a href="#mongoose_Mongoose-pluralize">Mongoose.prototype.pluralize()</a></li><li><a href="#mongoose_Mongoose-set">Mongoose.prototype.set()</a></li><li><a href="#mongoose_Mongoose-startSession">Mongoose.prototype.startSession()</a></li><li><a href="#mongoose_Mongoose-version">Mongoose.prototype.version</a></li></ul><hr class="separate-api-elements"><h3 id="mongoose_Mongoose"><a href="#mongoose_Mongoose">Mongoose()</a></h3><div><p>Mongoose constructor.</p>
-
-<p>The exports object of the <code>mongoose</code> module is an instance of this class. Most apps will only use this one instance.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Aggregate"><a href="#mongoose_Mongoose-Aggregate">Mongoose.prototype.Aggregate()</a></h3><div><p>The Mongoose Aggregate constructor</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-CastError"><a href="#mongoose_Mongoose-CastError">Mongoose.prototype.CastError()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">type
-<span class="method-type">&laquo;String&raquo;</span> The name of the type</li><li class="param">value
-<span class="method-type">&laquo;Any&raquo;</span> The value that failed to cast</li><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> The path <code>a.b.c</code> in the doc where this cast error occurred</li><li class="param">[reason]
-<span class="method-type">&laquo;Error&raquo;</span> The original error that was thrown</li></ul><div><p>The Mongoose CastError constructor</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Collection"><a href="#mongoose_Mongoose-Collection">Mongoose.prototype.Collection()</a></h3><div><p>The Mongoose Collection constructor</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Connection"><a href="#mongoose_Mongoose-Connection">Mongoose.prototype.Connection()</a></h3><div><p>The Mongoose <a href="#connection_Connection">Connection</a> constructor</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Decimal128"><a href="#mongoose_Mongoose-Decimal128">Mongoose.prototype.Decimal128</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose Decimal128 <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that should be <a href="http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-decimal.html">128-bit decimal floating points</a>. Do not use this to create a new Decimal128 instance, use <code>mongoose.Types.Decimal128</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> vehicleSchema = <span class="hljs-keyword">new</span> Schema({ fuelLevel: mongoose.Decimal128 });</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Document"><a href="#mongoose_Mongoose-Document">Mongoose.prototype.Document()</a></h3><div><p>The Mongoose <a href="#document-js">Document</a> constructor.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-DocumentProvider"><a href="#mongoose_Mongoose-DocumentProvider">Mongoose.prototype.DocumentProvider()</a></h3><div><p>The Mongoose DocumentProvider constructor. Mongoose users should not have to use this directly</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Error"><a href="#mongoose_Mongoose-Error">Mongoose.prototype.Error()</a></h3><div><p>The <a href="#error_MongooseError">MongooseError</a> constructor.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Mixed"><a href="#mongoose_Mongoose-Mixed">Mongoose.prototype.Mixed</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose Mixed <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that Mongoose's change tracking, casting, and validation should ignore.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ arbitrary: mongoose.Mixed });</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Model"><a href="#mongoose_Mongoose-Model">Mongoose.prototype.Model()</a></h3><div><p>The Mongoose <a href="#model_Model">Model</a> constructor.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Mongoose"><a href="#mongoose_Mongoose-Mongoose">Mongoose.prototype.Mongoose()</a></h3><div><p>The Mongoose constructor</p>
-
-<p>The exports of the mongoose module is an instance of this class.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> mongoose2 = <span class="hljs-keyword">new</span> mongoose.Mongoose();</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Number"><a href="#mongoose_Mongoose-Number">Mongoose.prototype.Number</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose Number <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that Mongoose should cast to numbers.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ num: mongoose.Number });
-<span class="hljs-comment">// Equivalent to:</span>
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ num: <span class="hljs-string">'number'</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-ObjectId"><a href="#mongoose_Mongoose-ObjectId">Mongoose.prototype.ObjectId</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose ObjectId <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that should be <a href="https://docs.mongodb.com/manual/reference/method/ObjectId/">MongoDB ObjectIds</a>. Do not use this to create a new ObjectId instance, use <code>mongoose.Types.ObjectId</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> childSchema = <span class="hljs-keyword">new</span> Schema({ parentId: mongoose.ObjectId });</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Promise"><a href="#mongoose_Mongoose-Promise">Mongoose.prototype.Promise</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose <a href="#promise_Promise">Promise</a> constructor.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-PromiseProvider"><a href="#mongoose_Mongoose-PromiseProvider">Mongoose.prototype.PromiseProvider()</a></h3><div><p>Storage layer for mongoose promises</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Query"><a href="#mongoose_Mongoose-Query">Mongoose.prototype.Query()</a></h3><div><p>The Mongoose <a href="#query_Query">Query</a> constructor.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-STATES"><a href="#mongoose_Mongoose-STATES">Mongoose.prototype.STATES</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Expose connection states for user-land</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Schema"><a href="#mongoose_Mongoose-Schema">Mongoose.prototype.Schema()</a></h3><div><p>The Mongoose <a href="#schema_Schema">Schema</a> constructor</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> Schema = mongoose.Schema;
-<span class="hljs-keyword">var</span> CatSchema = <span class="hljs-keyword">new</span> Schema(..);</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-SchemaType"><a href="#mongoose_Mongoose-SchemaType">Mongoose.prototype.SchemaType()</a></h3><div><p>The Mongoose <a href="#schematype_SchemaType">SchemaType</a> constructor</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-SchemaTypes"><a href="#mongoose_Mongoose-SchemaTypes">Mongoose.prototype.SchemaTypes</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The various Mongoose SchemaTypes.</p>
-
-<h4>Note:</h4>
-
-<p><em>Alias of mongoose.Schema.Types for backwards compatibility.</em></p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Types"><a href="#mongoose_Mongoose-Types">Mongoose.prototype.Types</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The various Mongoose Types.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> array = mongoose.Types.Array;</code></pre>
-
-<h4>Types:</h4>
-
-<ul>
-<li><a href="#types-objectid-js">ObjectId</a></li>
-<li><a href="#types-buffer-js">Buffer</a></li>
-<li><a href="#types-embedded-js">SubDocument</a></li>
-<li><a href="#types-array-js">Array</a></li>
-<li><a href="#types-documentarray-js">DocumentArray</a></li>
-</ul>
-
-<p>Using this exposed access to the <code>ObjectId</code> type, we can construct ids on demand.</p>
-
-<pre><code><span class="hljs-keyword">var</span> ObjectId = mongoose.Types.ObjectId;
-<span class="hljs-keyword">var</span> id1 = <span class="hljs-keyword">new</span> ObjectId;</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-VirtualType"><a href="#mongoose_Mongoose-VirtualType">Mongoose.prototype.VirtualType()</a></h3><div><p>The Mongoose <a href="#virtualtype_VirtualType">VirtualType</a> constructor</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-connect"><a href="#mongoose_Mongoose-connect">Mongoose.prototype.connect()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">uri(s)
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> passed down to the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html">MongoDB driver&#39;s <code>connect()</code> function</a>, except for 4 mongoose-specific options explained below.</li><ul style="margin-top: 0.5em"><li>[options.dbName]
-<span class="method-type">&laquo;String&raquo;</span> The name of the database we want to use. If not provided, use database name from connection string.</li></ul><ul style="margin-top: 0.5em"><li>[options.user]
-<span class="method-type">&laquo;String&raquo;</span> username for authentication, equivalent to <code>options.auth.user</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.pass]
-<span class="method-type">&laquo;String&raquo;</span> password for authentication, equivalent to <code>options.auth.password</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.autoIndex=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.</li></ul><ul style="margin-top: 0.5em"><li>[options.bufferCommands=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose specific option. Set to false to <a href="http://mongoosejs.com/docs/faq.html#callback_never_executes">disable buffering</a> on all models associated with this connection.</li></ul><ul style="margin-top: 0.5em"><li>[options.useCreateIndex=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose-specific option. If <code>true</code>, this connection will use <a href="/docs/deprecations.html#-ensureindex-"><code>createIndex()</code> instead of <code>ensureIndex()</code></a> for automatic index builds via <a href="/docs/api.html#model_Model.init"><code>Model.init()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.useFindAndModify=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> True by default. Set to <code>false</code> to make <code>findOneAndUpdate()</code> and <code>findOneAndRemove()</code> use native <code>findOneAndUpdate()</code> rather than <code>findAndModify()</code>.</li></ul><ul style="margin-top: 0.5em"><li>[options.useNewUrlParser=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> False by default. Set to <code>true</code> to make all connections set the <code>useNewUrlParser</code> option by default.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> resolves to <code>this</code> if connection succeeded</li></ul><div><p>Opens the default mongoose connection.</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.connect(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>);
-
-<span class="hljs-comment">// replica sets</span>
-<span class="hljs-keyword">var</span> uri = <span class="hljs-string">'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/mydatabase'</span>;
-mongoose.connect(uri);
-
-<span class="hljs-comment">// with options</span>
-mongoose.connect(uri, options);
-
-<span class="hljs-comment">// optional callback that gets fired when initial connection completed</span>
-<span class="hljs-keyword">var</span> uri = <span class="hljs-string">'mongodb://nonexistent.domain:27000'</span>;
-mongoose.connect(uri, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// if error is truthy, the initial connection failed.</span>
-})</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-connection"><a href="#mongoose_Mongoose-connection">Mongoose.prototype.connection</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span></li></ul><div><p>The Mongoose module's default connection. Equivalent to <code>mongoose.connections][0]</code>, see <a href="#mongoose_Mongoose-connections"><code>connections</code></a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.connect(...);
-mongoose.connection.on(<span class="hljs-string">'error'</span>, cb);</code></pre>
-
-<p>This is the connection used by default for every model created using <a href="#index_Mongoose-model">mongoose.model</a>.</p>
-
-<p>To create a new connection, use <a href="#mongoose_Mongoose-createConnection"><code>createConnection()</code></a>.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-connections"><a href="#mongoose_Mongoose-connections">Mongoose.prototype.connections</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span></li></ul><div><p>An array containing all <a href="connections.html">connections</a> associated with this Mongoose instance. By default, there is 1 connection. Calling <a href="#mongoose_Mongoose-createConnection"><code>createConnection()</code></a> adds a connection to this array.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.connections.length; <span class="hljs-comment">// 1, just the default connection</span>
-mongoose.connections[<span class="hljs-number">0</span>] === mongoose.connection; <span class="hljs-comment">// true</span>
-
-mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/test'</span>);
-mongoose.connections.length; <span class="hljs-comment">// 2</span></code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-createConnection"><a href="#mongoose_Mongoose-createConnection">Mongoose.prototype.createConnection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[uri]
-<span class="method-type">&laquo;String&raquo;</span> a mongodb:// URI</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> passed down to the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html">MongoDB driver&#39;s <code>connect()</code> function</a>, except for 4 mongoose-specific options explained below.</li><ul style="margin-top: 0.5em"><li>[options.user]
-<span class="method-type">&laquo;String&raquo;</span> username for authentication, equivalent to <code>options.auth.user</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.pass]
-<span class="method-type">&laquo;String&raquo;</span> password for authentication, equivalent to <code>options.auth.password</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.autoIndex=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.</li></ul><ul style="margin-top: 0.5em"><li>[options.bufferCommands=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose specific option. Set to false to <a href="http://mongoosejs.com/docs/faq.html#callback_never_executes">disable buffering</a> on all models associated with this connection.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> the created Connection object. Connections are thenable, so you can do <code>await mongoose.createConnection()</code></li></ul><div><p>Creates a Connection instance.</p>
-
-<p>Each <code>connection</code> instance maps to a single database. This method is helpful when mangaging multiple db connections.</p>
-
-<p><em>Options passed take precedence over options included in connection strings.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// with mongodb:// URI</span>
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>);
-
-<span class="hljs-comment">// and options</span>
-<span class="hljs-keyword">var</span> opts = { db: { native_parser: <span class="hljs-literal">true</span> }}
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>, opts);
-
-<span class="hljs-comment">// replica sets</span>
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/database'</span>);
-
-<span class="hljs-comment">// and options</span>
-<span class="hljs-keyword">var</span> opts = { replset: { strategy: <span class="hljs-string">'ping'</span>, rs_name: <span class="hljs-string">'testSet'</span> }}
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/database'</span>, opts);
-
-<span class="hljs-comment">// and options</span>
-<span class="hljs-keyword">var</span> opts = { server: { auto_reconnect: <span class="hljs-literal">false</span> }, user: <span class="hljs-string">'username'</span>, pass: <span class="hljs-string">'mypassword'</span> }
-db = mongoose.createConnection(<span class="hljs-string">'localhost'</span>, <span class="hljs-string">'database'</span>, port, opts)
-
-<span class="hljs-comment">// initialize now, connect later</span>
-db = mongoose.createConnection();
-db.openUri(<span class="hljs-string">'localhost'</span>, <span class="hljs-string">'database'</span>, port, [opts]);</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-deleteModel"><a href="#mongoose_Mongoose-deleteModel">Mongoose.prototype.deleteModel()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|RegExp&raquo;</span> if string, the name of the model to remove. If regexp, removes all models whose name matches the regexp.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Mongoose&raquo;</span> this</li></ul><div><p>Removes the model named <code>name</code> from the default connection, if it exists. You can use this function to clean up any models you created in your tests to prevent OverwriteModelErrors.</p>
-
-<p>Equivalent to <code>mongoose.connection.deleteModel(name)</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-built_in">console</span>.log(mongoose.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// Model object</span>
-mongoose.deleteModel(<span class="hljs-string">'User'</span>);
-<span class="hljs-built_in">console</span>.log(mongoose.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// undefined</span>
-
-<span class="hljs-comment">// Usually useful in a Mocha `afterEach()` hook</span>
-afterEach(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  mongoose.deleteModel(<span class="hljs-regexp">/.+/</span>); <span class="hljs-comment">// Delete every model</span>
-});</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-disconnect"><a href="#mongoose_Mongoose-disconnect">Mongoose.prototype.disconnect()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> called after all connection close, or when first error occurred.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> resolves when all connections are closed, or rejects with the first error that occurred.</li></ul><div><p>Runs <code>.close()</code> on all connections in parallel.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-driver"><a href="#mongoose_Mongoose-driver">Mongoose.prototype.driver</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The underlying driver this Mongoose instance uses to communicate with the database. A driver is a Mongoose-specific interface that defines functions like <code>find()</code>.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-get"><a href="#mongoose_Mongoose-get">Mongoose.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Gets mongoose options</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.get(<span class="hljs-string">'test'</span>) <span class="hljs-comment">// returns the 'test' value</span></code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-model"><a href="#mongoose_Mongoose-model">Mongoose.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|Function&raquo;</span> model name or class extending Model</li><li class="param">[schema]
-<span class="method-type">&laquo;Schema&raquo;</span> the schema to use.</li><li class="param">[collection]
-<span class="method-type">&laquo;String&raquo;</span> name (optional, inferred from model name)</li><li class="param">[skipInit]
-<span class="method-type">&laquo;Boolean&raquo;</span> whether to skip initialization (defaults to false)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Model&raquo;</span> The model associated with <code>name</code>. Mongoose will create the model if it doesn&#39;t already exist.</li></ul><div><p>Defines a model or retrieves it.</p>
-
-<p>Models defined on the <code>mongoose</code> instance are available to all connection created by the same <code>mongoose</code> instance.</p>
-
-<p>If you call <code>mongoose.model()</code> with twice the same name but a different schema, you will get an <code>OverwriteModelError</code>. If you call <code>mongoose.model()</code> with the same name and same schema, you'll get the same schema back.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-
-<span class="hljs-comment">// define an Actor model with this mongoose instance</span>
-<span class="hljs-keyword">const</span> Schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-mongoose.model(<span class="hljs-string">'Actor'</span>, schema);
-
-<span class="hljs-comment">// create a new connection</span>
-<span class="hljs-keyword">var</span> conn = mongoose.createConnection(..);
-
-<span class="hljs-comment">// create Actor model</span>
-<span class="hljs-keyword">var</span> Actor = conn.model(<span class="hljs-string">'Actor'</span>, schema);
-conn.model(<span class="hljs-string">'Actor'</span>) === Actor; <span class="hljs-comment">// true</span>
-conn.model(<span class="hljs-string">'Actor'</span>, schema) === Actor; <span class="hljs-comment">// true, same schema</span>
-conn.model(<span class="hljs-string">'Actor'</span>, schema, <span class="hljs-string">'actors'</span>) === Actor; <span class="hljs-comment">// true, same schema and collection name</span>
-
-<span class="hljs-comment">// This throws an `OverwriteModelError` because the schema is different.</span>
-conn.model(<span class="hljs-string">'Actor'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));</code></pre>
-
-<p><em>When no <code>collection</code> argument is passed, Mongoose uses the model name. If you don't like this behavior, either pass a collection name, use <code>mongoose.pluralize()</code>, or set your schemas collection name option.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { collection: <span class="hljs-string">'actor'</span> });
-
-<span class="hljs-comment">// or</span>
-
-schema.set(<span class="hljs-string">'collection'</span>, <span class="hljs-string">'actor'</span>);
-
-<span class="hljs-comment">// or</span>
-
-<span class="hljs-keyword">var</span> collectionName = <span class="hljs-string">'actor'</span>
-<span class="hljs-keyword">var</span> M = mongoose.model(<span class="hljs-string">'Actor'</span>, schema, collectionName)</code></pre></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-modelNames"><a href="#mongoose_Mongoose-modelNames">Mongoose.prototype.modelNames()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns an array of model names created on this instance of Mongoose.</p>
-
-<h4>Note:</h4>
-
-<p><em>Does not include names of models created using <code>connection.model()</code>.</em></p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-mongo"><a href="#mongoose_Mongoose-mongo">Mongoose.prototype.mongo</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The <a href="https://github.com/mongodb/node-mongodb-native">node-mongodb-native</a> driver Mongoose uses.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-mquery"><a href="#mongoose_Mongoose-mquery">Mongoose.prototype.mquery</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The <a href="https://github.com/aheckmann/mquery">mquery</a> query builder Mongoose uses.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-now"><a href="#mongoose_Mongoose-now">Mongoose.prototype.now()</a></h3><div><p>Mongoose uses this function to get the current time when setting <a href="/docs/guide.html#timestamps">timestamps</a>. You may stub out this function using a tool like <a href="https://www.npmjs.com/package/sinon">Sinon</a> for testing.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-plugin"><a href="#mongoose_Mongoose-plugin">Mongoose.prototype.plugin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> plugin callback</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> optional options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Mongoose&raquo;</span> this</li></ul><div><p>Declares a global plugin executed on all Schemas.</p>
-
-<p>Equivalent to calling <code>.plugin(fn)</code> on each Schema you create.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-pluralize"><a href="#mongoose_Mongoose-pluralize">Mongoose.prototype.pluralize()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[fn]
-<span class="method-type">&laquo;Function|null&raquo;</span> overwrites the function used to pluralize collection names</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Function,null&raquo;</span> the current function used to pluralize collection names, defaults to the legacy function from <code>mongoose-legacy-pluralize</code>.</li></ul><div><p>Getter/setter around function for pluralizing collection names.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-set"><a href="#mongoose_Mongoose-set">Mongoose.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;String|Function|Boolean&raquo;</span> </li></ul><div><p>Sets mongoose options</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.set(<span class="hljs-string">'test'</span>, value) <span class="hljs-comment">// sets the 'test' option to `value`</span>
-
-mongoose.set(<span class="hljs-string">'debug'</span>, <span class="hljs-literal">true</span>) <span class="hljs-comment">// enable logging collection methods + arguments to the console</span>
-
-mongoose.set(<span class="hljs-string">'debug'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">collectionName, methodName, arg1, arg2...</span>) </span>{}); <span class="hljs-comment">// use custom function to log collection methods + arguments</span></code></pre>
-
-<h2>Currently supported options are</h2>
-
-<ul>
-<li>'debug': prints the operations mongoose sends to MongoDB to the console</li>
-<li>'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models</li>
-<li>'useCreateIndex': false by default. Set to <code>true</code> to make Mongoose's default index build use <code>createIndex()</code> instead of <code>ensureIndex()</code> to avoid deprecation warnings from the MongoDB driver.</li>
-<li>'useFindAndModify': true by default. Set to <code>false</code> to make <code>findOneAndUpdate()</code> and <code>findOneAndRemove()</code> use native <code>findOneAndUpdate()</code> rather than <code>findAndModify()</code>.</li>
-<li>'useNewUrlParser': false by default. Set to <code>true</code> to make all connections set the <code>useNewUrlParser</code> option by default</li>
-<li>'cloneSchemas': false by default. Set to <code>true</code> to <code>clone()</code> all schemas before compiling into a model.</li>
-<li>'applyPluginsToDiscriminators': false by default. Set to true to apply global plugins to discriminator schemas. This typically isn't necessary because plugins are applied to the base schema and discriminators copy all middleware, methods, statics, and properties from the base schema.</li>
-<li>'objectIdGetter': true by default. Mongoose adds a getter to MongoDB ObjectId's called <code>_id</code> that returns <code>this</code> for convenience with populate. Set this to false to remove the getter.</li>
-<li>'runValidators': false by default. Set to true to enable <a href="/docs/validation.html#update-validators">update validators</a> for all validators by default.</li>
-<li>'toObject': <code>{ transform: true, flattenDecimals: true }</code> by default. Overwrites default objects to <a href="/docs/api.html#document_Document-toObject"><code>toObject()</code></a></li>
-<li>'toJSON': <code>{ transform: true, flattenDecimals: true }</code> by default. Overwrites default objects to <a href="/docs/api.html#document_Document-toJSON"><code>toJSON()</code></a>, for determining how Mongoose documents get serialized by <code>JSON.stringify()</code></li>
-<li>'strict': true by default, may be <code>false</code>, <code>true</code>, or <code>'throw'</code>. Sets the default strict mode for schemas.</li>
-<li>'selectPopulatedPaths': true by default. Set to false to opt out of Mongoose adding all fields that you <code>populate()</code> to your <code>select()</code>. The schema-level option <code>selectPopulatedPaths</code> overwrites this one.</li>
-</ul></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-startSession"><a href="#mongoose_Mongoose-startSession">Mongoose.prototype.startSession()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#startSession">mongodb driver options</a></li><ul style="margin-top: 0.5em"><li>[options.causalConsistency=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to disable causal consistency</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&lt;ClientSession&gt;&raquo;</span> promise that resolves to a MongoDB driver <code>ClientSession</code></li></ul><div><p><em>Requires MongoDB >= 3.6.0.</em> Starts a <a href="https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions">MongoDB session</a> for benefits like causal consistency, <a href="https://docs.mongodb.com/manual/core/retryable-writes/">retryable writes</a>, and <a href="http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html">transactions</a>.</p>
-
-<p>Calling <code>mongoose.startSession()</code> is equivalent to calling <code>mongoose.connection.startSession()</code>. Sessions are scoped to a connection, so calling <code>mongoose.startSession()</code> starts a session on the <a href="/docs/api.html#mongoose_Mongoose-connection">default mongoose connection</a>.</p></div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-version"><a href="#mongoose_Mongoose-version">Mongoose.prototype.version</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose version</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-built_in">console</span>.log(mongoose.version); <span class="hljs-comment">// '5.x.x'</span></code></pre></div><hr class="separate-api"><h2 class="item-header" id="Schema"><a href="#Schema">Schema</a></h2><ul><li><a href="#schema_Schema">Schema()</a></li><li><a href="#schema_Schema.Types">Schema.Types</a></li><li><a href="#schema_Schema-indexTypes">Schema.indexTypes</a></li><li><a href="#schema_Schema-add">Schema.prototype.add()</a></li><li><a href="#schema_Schema-childSchemas">Schema.prototype.childSchemas</a></li><li><a href="#schema_Schema-clone">Schema.prototype.clone()</a></li><li><a href="#schema_Schema-eachPath">Schema.prototype.eachPath()</a></li><li><a href="#schema_Schema-get">Schema.prototype.get()</a></li><li><a href="#schema_Schema-index">Schema.prototype.index()</a></li><li><a href="#schema_Schema-indexes">Schema.prototype.indexes()</a></li><li><a href="#schema_Schema-loadClass">Schema.prototype.loadClass()</a></li><li><a href="#schema_Schema-method">Schema.prototype.method()</a></li><li><a href="#schema_Schema-obj">Schema.prototype.obj</a></li><li><a href="#schema_Schema-path">Schema.prototype.path()</a></li><li><a href="#schema_Schema-pathType">Schema.prototype.pathType()</a></li><li><a href="#schema_Schema-plugin">Schema.prototype.plugin()</a></li><li><a href="#schema_Schema-post">Schema.prototype.post()</a></li><li><a href="#schema_Schema-pre">Schema.prototype.pre()</a></li><li><a href="#schema_Schema-queue">Schema.prototype.queue()</a></li><li><a href="#schema_Schema-remove">Schema.prototype.remove()</a></li><li><a href="#schema_Schema-requiredPaths">Schema.prototype.requiredPaths()</a></li><li><a href="#schema_Schema-set">Schema.prototype.set()</a></li><li><a href="#schema_Schema-static">Schema.prototype.static()</a></li><li><a href="#schema_Schema-virtual">Schema.prototype.virtual()</a></li><li><a href="#schema_Schema-virtualpath">Schema.prototype.virtualpath()</a></li><li><a href="#schema_Schema.reserved">Schema.reserved</a></li></ul><hr class="separate-api-elements"><h3 id="schema_Schema"><a href="#schema_Schema">Schema()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[definition]
-<span class="method-type">&laquo;Object|Schema|Array&raquo;</span> Can be one of: object describing schema paths, or schema to copy, or array of objects and schemas</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Schema constructor.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> child = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, age: <span class="hljs-built_in">Number</span>, children: [child] });
-<span class="hljs-keyword">var</span> Tree = mongoose.model(<span class="hljs-string">'Tree'</span>, schema);
-
-<span class="hljs-comment">// setting schema options</span>
-<span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { _id: <span class="hljs-literal">false</span>, autoIndex: <span class="hljs-literal">false</span> })</code></pre>
-
-<h4>Options:</h4>
-
-<ul>
-<li><a href="/docs/guide.html#autoIndex">autoIndex</a>: bool - defaults to null (which means use the connection's autoIndex option)</li>
-<li><a href="/docs/guide.html#autoCreate">autoCreate</a>: bool - defaults to null (which means use the connection's autoCreate option)</li>
-<li><a href="/docs/guide.html#bufferCommands">bufferCommands</a>: bool - defaults to true</li>
-<li><a href="/docs/guide.html#capped">capped</a>: bool - defaults to false</li>
-<li><a href="/docs/guide.html#collection">collection</a>: string - no default</li>
-<li><a href="/docs/guide.html#id">id</a>: bool - defaults to true</li>
-<li><a href="/docs/guide.html#_id">_id</a>: bool - defaults to true</li>
-<li><code>minimize</code>: bool - controls <a href="#document_Document-toObject">document#toObject</a> behavior when called manually - defaults to true</li>
-<li><a href="/docs/guide.html#read">read</a>: string</li>
-<li><a href="/docs/guide.html#writeConcern">writeConcern</a>: object - defaults to null, use to override <a href="https://docs.mongodb.com/manual/reference/write-concern/">the MongoDB server's default write concern settings</a></li>
-<li><a href="/docs/guide.html#shardKey">shardKey</a>: object - defaults to <code>null</code></li>
-<li><a href="/docs/guide.html#strict">strict</a>: bool - defaults to true</li>
-<li><a href="/docs/guide.html#strictQuery">strictQuery</a>: bool - defaults to false</li>
-<li><a href="/docs/guide.html#toJSON">toJSON</a> - object - no default</li>
-<li><a href="/docs/guide.html#toObject">toObject</a> - object - no default</li>
-<li><a href="/docs/guide.html#typeKey">typeKey</a> - string - defaults to 'type'</li>
-<li><a href="/docs/guide.html#useNestedStrict">useNestedStrict</a> - boolean - defaults to false</li>
-<li><a href="/docs/guide.html#validateBeforeSave">validateBeforeSave</a> - bool - defaults to <code>true</code></li>
-<li><a href="/docs/guide.html#versionKey">versionKey</a>: string - defaults to "__v"</li>
-<li><a href="/docs/guide.html#collation">collation</a>: object - defaults to null (which means use no collation)</li>
-<li><a href="/docs/guide.html#selectPopulatedPaths">selectPopulatedPaths</a>: boolean - defaults to <code>true</code></li>
-<li><a href="/docs/guide.html#skipVersioning">skipVersioning</a>: object - paths to exclude from versioning</li>
-<li><a href="/docs/guide.html#timestamps">timestamps</a>: object or boolean - defaults to <code>false</code>. If true, Mongoose adds <code>createdAt</code> and <code>updatedAt</code> properties to your schema and manages those properties for you.</li>
-<li><a href="/docs/guide.html#storeSubdocValidationError">storeSubdocValidationError</a>: boolean - Defaults to true. If false, Mongoose will wrap validation errors in single nested document subpaths into a single validation error on the single nested subdoc's path.</li>
-</ul>
-
-<h4>Note:</h4>
-
-<p><em>When nesting schemas, (<code>children</code> in the example above), always declare the child schema first before passing it into its parent.</em></p></div><hr class="separate-api-elements"><h3 id="schema_Schema.Types"><a href="#schema_Schema.Types">Schema.Types</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The various built-in Mongoose Schema Types.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> ObjectId = mongoose.Schema.Types.ObjectId;</code></pre>
-
-<h4>Types:</h4>
-
-<ul>
-<li><a href="#schema-string-js">String</a></li>
-<li><a href="#schema-number-js">Number</a></li>
-<li><a href="#schema-boolean-js">Boolean</a> | Bool</li>
-<li><a href="#schema-array-js">Array</a></li>
-<li><a href="#schema-buffer-js">Buffer</a></li>
-<li><a href="#schema-date-js">Date</a></li>
-<li><a href="#schema-objectid-js">ObjectId</a> | Oid</li>
-<li><a href="#schema-mixed-js">Mixed</a></li>
-</ul>
-
-<p>Using this exposed access to the <code>Mixed</code> SchemaType, we can use them in our schema.</p>
-
-<pre><code><span class="hljs-keyword">var</span> Mixed = mongoose.Schema.Types.Mixed;
-<span class="hljs-keyword">new</span> mongoose.Schema({ _user: Mixed })</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-indexTypes"><a href="#schema_Schema-indexTypes">Schema.indexTypes</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The allowed index types</p></div><hr class="separate-api-elements"><h3 id="schema_Schema-add"><a href="#schema_Schema-add">Schema.prototype.add()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;Object|Schema&raquo;</span> plain object with paths to add, or another schema</li><li class="param">[prefix]
-<span class="method-type">&laquo;String&raquo;</span> path to prefix the newly added paths with</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> the Schema instance</li></ul><div><p>Adds key path / schema type pairs to this schema.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> ToySchema = <span class="hljs-keyword">new</span> Schema();
-ToySchema.add({ name: <span class="hljs-string">'string'</span>, color: <span class="hljs-string">'string'</span>, price: <span class="hljs-string">'number'</span> });
-
-<span class="hljs-keyword">const</span> TurboManSchema = <span class="hljs-keyword">new</span> Schema();
-<span class="hljs-comment">// You can also `add()` another schema and copy over all paths, virtuals,</span>
-<span class="hljs-comment">// getters, setters, indexes, methods, and statics.</span>
-TurboManSchema.add(ToySchema).add({ year: <span class="hljs-built_in">Number</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-childSchemas"><a href="#schema_Schema-childSchemas">Schema.prototype.childSchemas</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Array of child schemas (from document arrays and single nested subdocs) and their corresponding compiled models. Each element of the array is an object with 2 properties: <code>schema</code> and <code>model</code>.</p>
-
-<p>This property is typically only useful for plugin authors and advanced users. You do not need to interact with this property at all to use mongoose.</p></div><hr class="separate-api-elements"><h3 id="schema_Schema-clone"><a href="#schema_Schema-clone">Schema.prototype.clone()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> the cloned schema</li></ul><div><p>Returns a deep copy of the schema</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> clone = schema.clone();
-clone === schema; <span class="hljs-comment">// false</span>
-clone.path(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// SchemaString { ... }</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-eachPath"><a href="#schema_Schema-eachPath">Schema.prototype.eachPath()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> callback function</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> this</li></ul><div><p>Iterates the schemas paths similar to Array#forEach.</p>
-
-<p>The callback is passed the pathname and the schemaType instance.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, registeredAt: <span class="hljs-built_in">Date</span> });
-userSchema.eachPath((pathname, schematype) =&gt; {
-  <span class="hljs-comment">// Prints twice:</span>
-  <span class="hljs-comment">// name SchemaString { ... }</span>
-  <span class="hljs-comment">// registeredAt SchemaDate { ... }</span>
-  <span class="hljs-built_in">console</span>.log(pathname, schematype);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-get"><a href="#schema_Schema-get">Schema.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> option name</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Any&raquo;</span> the option&#39;s value</li></ul><div><p>Gets a schema option.</p>
-
-<h4>Example:</h4>
-
-<pre><code>schema.get(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// true</span>
-schema.set(<span class="hljs-string">'strict'</span>, <span class="hljs-literal">false</span>);
-schema.get(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// false</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-index"><a href="#schema_Schema-index">Schema.prototype.index()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fields
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Options to pass to <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#createIndex">MongoDB driver&#39;s <code>createIndex()</code> function</a></li><ul style="margin-top: 0.5em"><li>[options.expires=null]
-<span class="method-type">&laquo;String&raquo;</span> Mongoose-specific syntactic sugar, uses <a href="https://www.npmjs.com/package/ms">ms</a> to convert <code>expires</code> option into seconds for the <code>expireAfterSeconds</code> in the above link.</li></ul></ul><div><p>Defines an index (most likely compound) for this schema.</p>
-
-<h4>Example</h4>
-
-<pre><code>schema.index({ first: <span class="hljs-number">1</span>, last: <span class="hljs-number">-1</span> })</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-indexes"><a href="#schema_Schema-indexes">Schema.prototype.indexes()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> list of indexes defined in the schema</li></ul><div><p>Returns a list of indexes that this schema declares, via <code>schema.index()</code> or by <code>index: true</code> in a path's options.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  email: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span>, unique: <span class="hljs-literal">true</span> },
-  registeredAt: { type: <span class="hljs-built_in">Date</span>, index: <span class="hljs-literal">true</span> }
-});
-
-<span class="hljs-comment">// [ [ { email: 1 }, { unique: true, background: true } ],</span>
-<span class="hljs-comment">//   [ { registeredAt: 1 }, { background: true } ] ]</span>
-userSchema.indexes();</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-loadClass"><a href="#schema_Schema-loadClass">Schema.prototype.loadClass()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">model
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[virtualsOnly]
-<span class="method-type">&laquo;Boolean&raquo;</span> if truthy, only pulls virtuals from the class, not methods or statics</li></ul><div><p>Loads an ES6 class into a schema. Maps <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set">setters</a> + <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get">getters</a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static">static methods</a>, and <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Class_body_and_method_definitions">instance methods</a> to schema <a href="http://mongoosejs.com/docs/guide.html#virtuals">virtuals</a>, <a href="http://mongoosejs.com/docs/guide.html#statics">statics</a>, and <a href="http://mongoosejs.com/docs/guide.html#methods">methods</a>.</p>
-
-<h4>Example:</h4>
-
-<div class="highlight"><pre lang="javascript">const md5 = require('md5');
-const userSchema = new Schema({ email: String });
-class UserClass {
-  // `gravatarImage` becomes a virtual
-  get gravatarImage() {
-    const hash = md5(this.email.toLowerCase());
-    return `<a href='https://www.gravatar.com/avatar/${hash}`'>https://www.gravatar.com/avatar/${hash}`</a>;
-  }
-
-  // `getProfileUrl()` becomes a document method
-  getProfileUrl() {
-    return `<a href='https://mysite.com/${this.email}`'>https://mysite.com/${this.email}`</a>;
-  }
-
-  // `findByEmail()` becomes a static
-  static findByEmail(email) {
-    return this.findOne({ email });
-  }
-}
-
-// `schema` will now have a `gravatarImage` virtual, a `getProfileUrl()` method,
-// and a `findByEmail()` static
-userSchema.loadClass(UserClass);
-</pre></div></div><hr class="separate-api-elements"><h3 id="schema_Schema-method"><a href="#schema_Schema-method">Schema.prototype.method()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">method
-<span class="method-type">&laquo;String|Object&raquo;</span> name</li><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Adds an instance method to documents constructed from Models compiled from this schema.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = kittySchema = <span class="hljs-keyword">new</span> Schema(..);
-
-schema.method(<span class="hljs-string">'meow'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'meeeeeoooooooooooow'</span>);
-})
-
-<span class="hljs-keyword">var</span> Kitty = mongoose.model(<span class="hljs-string">'Kitty'</span>, schema);
-
-<span class="hljs-keyword">var</span> fizz = <span class="hljs-keyword">new</span> Kitty;
-fizz.meow(); <span class="hljs-comment">// meeeeeooooooooooooow</span></code></pre>
-
-<p>If a hash of name/fn pairs is passed as the only argument, each name/fn pair will be added as methods.</p>
-
-<pre><code>schema.method({
-    purr: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{}
-  , scratch: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{}
-});
-
-<span class="hljs-comment">// later</span>
-fizz.purr();
-fizz.scratch();</code></pre>
-
-<p>NOTE: <code>Schema.method()</code> adds instance methods to the <code>Schema.methods</code> object. You can also add instance methods directly to the <code>Schema.methods</code> object as seen in the <a href="./guide.html#methods">guide</a></p></div><hr class="separate-api-elements"><h3 id="schema_Schema-obj"><a href="#schema_Schema-obj">Schema.prototype.obj</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The original object passed to the schema constructor</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ a: <span class="hljs-built_in">String</span> }).add({ b: <span class="hljs-built_in">String</span> });
-schema.obj; <span class="hljs-comment">// { a: String }</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-path"><a href="#schema_Schema-path">Schema.prototype.path()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">constructor
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Gets/sets schema paths.</p>
-
-<p>Sets a path (if arity 2) Gets a path (if arity 1)</p>
-
-<h4>Example</h4>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>) <span class="hljs-comment">// returns a SchemaType</span>
-schema.path(<span class="hljs-string">'name'</span>, <span class="hljs-built_in">Number</span>) <span class="hljs-comment">// changes the schemaType of `name` to Number</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-pathType"><a href="#schema_Schema-pathType">Schema.prototype.pathType()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Returns the pathType of <code>path</code> for this schema.</p>
-
-<p>Given a path, returns whether it is a real, virtual, nested, or ad-hoc/undefined path.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, nested: { foo: <span class="hljs-built_in">String</span> } });
-s.virtual(<span class="hljs-string">'foo'</span>).get(() =&gt; <span class="hljs-number">42</span>);
-s.pathType(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// "real"</span>
-s.pathType(<span class="hljs-string">'nested'</span>); <span class="hljs-comment">// "nested"</span>
-s.pathType(<span class="hljs-string">'foo'</span>); <span class="hljs-comment">// "virtual"</span>
-s.pathType(<span class="hljs-string">'fail'</span>); <span class="hljs-comment">// "adhocOrUndefined"</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-plugin"><a href="#schema_Schema-plugin">Schema.prototype.plugin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">plugin
-<span class="method-type">&laquo;Function&raquo;</span> callback</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Registers a plugin for this schema.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-s.plugin(schema =&gt; <span class="hljs-built_in">console</span>.log(schema.path(<span class="hljs-string">'name'</span>).path));
-mongoose.model(<span class="hljs-string">'Test'</span>, schema); <span class="hljs-comment">// Prints 'name'</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-post"><a href="#schema_Schema-post">Schema.prototype.post()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">The
-<span class="method-type">&laquo;String|RegExp&raquo;</span> method name or regular expression to match method name</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.document]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on document middleware.</li></ul><ul style="margin-top: 0.5em"><li>[options.query]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on query middleware.</li></ul><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><div><p>Defines a post hook for the document</p>
-
-<pre><code>var schema = new Schema(..);
-schema.post('save', function (doc) {
-  console.log('this fired after a document was saved');
-});
-
-schema.post('find', function(docs) {
-  console.log('this fired after you ran a find query');
-});
-
-schema.post(/Many$/, function(res) {
-  console.log('this fired after you ran `updateMany()` or `deleteMany()`);
-});
-
-var Model = mongoose.model('Model', schema);
-
-var m = new Model(..);
-m.save(function(err) {
-  console.log('this fires after the `post` hook');
-});
-
-m.find(function(err, docs) {
-  console.log('this fires after the post find hook');
-});</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-pre"><a href="#schema_Schema-pre">Schema.prototype.pre()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">The
-<span class="method-type">&laquo;String|RegExp&raquo;</span> method name or regular expression to match method name</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.document]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on document middleware.</li></ul><ul style="margin-top: 0.5em"><li>[options.query]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on query middleware.</li></ul><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Defines a pre hook for the document.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> toySchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, created: <span class="hljs-built_in">Date</span> });
-
-toySchema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.created) <span class="hljs-keyword">this</span>.created = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>;
-  next();
-});
-
-toySchema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">if</span> (<span class="hljs-keyword">this</span>.name !== <span class="hljs-string">'Woody'</span>) <span class="hljs-keyword">this</span>.name = <span class="hljs-string">'Woody'</span>;
-  next();
-});
-
-<span class="hljs-comment">// Equivalent to calling `pre()` on `find`, `findOne`, `findOneAndUpdate`.</span>
-toySchema.pre(<span class="hljs-regexp">/^find/</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>.getFilter());
-});</code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-queue"><a href="#schema_Schema-queue">Schema.prototype.queue()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> name of the document method to call later</li><li class="param">args
-<span class="method-type">&laquo;Array&raquo;</span> arguments to pass to the method</li></ul><div><p>Adds a method call to the queue.</p>
-
-<h4>Example:</h4>
-
-<pre><code>schema.methods.print = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>); };
-schema.queue(<span class="hljs-string">'print'</span>, []); <span class="hljs-comment">// Print the doc every one is instantiated</span>
-
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">new</span> Model({ name: <span class="hljs-string">'test'</span> }); <span class="hljs-comment">// Prints '{"_id": ..., "name": "test" }'</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-remove"><a href="#schema_Schema-remove">Schema.prototype.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Array&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> the Schema instance</li></ul><div><p>Removes the given <code>path</code> (or [<code>paths</code>]).</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, age: <span class="hljs-built_in">Number</span> });
-schema.remove(<span class="hljs-string">'name'</span>);
-schema.path(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// Undefined</span>
-schema.path(<span class="hljs-string">'age'</span>); <span class="hljs-comment">// SchemaNumber { ... }</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-requiredPaths"><a href="#schema_Schema-requiredPaths">Schema.prototype.requiredPaths()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">invalidate
-<span class="method-type">&laquo;Boolean&raquo;</span> refresh the cache</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns an Array of path strings that are required by this schema.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  age: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  notes: <span class="hljs-built_in">String</span>
-});
-s.requiredPaths(); <span class="hljs-comment">// [ 'age', 'name' ]</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-set"><a href="#schema_Schema-set">Schema.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> option name</li><li class="param">[value]
-<span class="method-type">&laquo;Object&raquo;</span> if not passed, the current option value is returned</li></ul><div><p>Sets/gets a schema option.</p>
-
-<h4>Example</h4>
-
-<pre><code>schema.set(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// 'true' by default</span>
-schema.set(<span class="hljs-string">'strict'</span>, <span class="hljs-literal">false</span>); <span class="hljs-comment">// Sets 'strict' to false</span>
-schema.set(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// 'false'</span></code></pre></div><hr class="separate-api-elements"><h3 id="schema_Schema-static"><a href="#schema_Schema-static">Schema.prototype.static()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|Object&raquo;</span> </li><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Adds static "class" methods to Models compiled from this schema.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema(..);
-<span class="hljs-comment">// Equivalent to `schema.statics.findByName = function(name) {}`;</span>
-schema.static(<span class="hljs-string">'findByName'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">name</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.find({ name: name });
-});
-
-<span class="hljs-keyword">const</span> Drink = mongoose.model(<span class="hljs-string">'Drink'</span>, schema);
-<span class="hljs-keyword">await</span> Drink.findByName(<span class="hljs-string">'LaCroix'</span>);</code></pre>
-
-<p>If a hash of name/fn pairs is passed as the only argument, each name/fn pair will be added as statics.</p></div><hr class="separate-api-elements"><h3 id="schema_Schema-virtual"><a href="#schema_Schema-virtual">Schema.prototype.virtual()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.ref]
-<span class="method-type">&laquo;String|Model&raquo;</span> model name or model instance. Marks this as a <a href="populate.html#populate-virtuals">populate virtual</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.localField]
-<span class="method-type">&laquo;String|Function&raquo;</span> Required for populate virtuals. See <a href="populate.html#populate-virtuals">populate virtual docs</a> for more information.</li></ul><ul style="margin-top: 0.5em"><li>[options.foreignField]
-<span class="method-type">&laquo;String|Function&raquo;</span> Required for populate virtuals. See <a href="populate.html#populate-virtuals">populate virtual docs</a> for more information.</li></ul><ul style="margin-top: 0.5em"><li>[options.justOne=false]
-<span class="method-type">&laquo;Boolean|Function&raquo;</span> Only works with populate virtuals. If truthy, will be a single doc or <code>null</code>. Otherwise, the populate virtual will be an array.</li></ul><ul style="margin-top: 0.5em"><li>[options.count=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> Only works with populate virtuals. If truthy, this populate virtual will contain the number of documents rather than the documents themselves when you <code>populate()</code>.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> </li></ul><div><p>Creates a virtual type with the given name.</p></div><hr class="separate-api-elements"><h3 id="schema_Schema-virtualpath"><a href="#schema_Schema-virtualpath">Schema.prototype.virtualpath()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> </li></ul><div><p>Returns the virtual type with the given <code>name</code>.</p></div><hr class="separate-api-elements"><h3 id="schema_Schema.reserved"><a href="#schema_Schema.reserved">Schema.reserved</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Reserved document keys.</p>
-
-<p>Keys in this object are names that are rejected in schema declarations because they conflict with Mongoose functionality. If you create a schema using <code>new Schema()</code> with one of these property names, Mongoose will throw an error.</p>
-
-<ul>
-<li>prototype</li>
-<li>emit</li>
-<li>on</li>
-<li>once</li>
-<li>listeners</li>
-<li>removeListener</li>
-<li>collection</li>
-<li>db</li>
-<li>errors</li>
-<li>init</li>
-<li>isModified</li>
-<li>isNew</li>
-<li>get</li>
-<li>modelName</li>
-<li>save</li>
-<li>schema</li>
-<li>toObject</li>
-<li>validate</li>
-<li>remove</li>
-<li>populated</li>
-<li>_pres</li>
-<li>_posts</li>
-</ul>
-
-<p><em>NOTE:</em> Use of these terms as method names is permitted, but play at your own risk, as they may be existing mongoose document methods you are stomping on.</p>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema(..);
- schema.methods.init = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{} <span class="hljs-comment">// potentially breaking</span></code></pre></div><hr class="separate-api"><h2 class="item-header" id="Connection"><a href="#Connection">Connection</a></h2><ul><li><a href="#connection_Connection">Connection()</a></li><li><a href="#connection_Connection-close">Connection.prototype.close()</a></li><li><a href="#connection_Connection-collection">Connection.prototype.collection()</a></li><li><a href="#connection_Connection-collections">Connection.prototype.collections</a></li><li><a href="#connection_Connection-config">Connection.prototype.config</a></li><li><a href="#connection_Connection-createCollection">Connection.prototype.createCollection()</a></li><li><a href="#connection_Connection-db">Connection.prototype.db</a></li><li><a href="#connection_Connection-deleteModel">Connection.prototype.deleteModel()</a></li><li><a href="#connection_Connection-dropCollection">Connection.prototype.dropCollection()</a></li><li><a href="#connection_Connection-dropDatabase">Connection.prototype.dropDatabase()</a></li><li><a href="#connection_Connection-get">Connection.prototype.get()</a></li><li><a href="#connection_Connection-host">Connection.prototype.host</a></li><li><a href="#connection_Connection-model">Connection.prototype.model()</a></li><li><a href="#connection_Connection-modelNames">Connection.prototype.modelNames()</a></li><li><a href="#connection_Connection-name">Connection.prototype.name</a></li><li><a href="#connection_Connection-openUri">Connection.prototype.openUri()</a></li><li><a href="#connection_Connection-pass">Connection.prototype.pass</a></li><li><a href="#connection_Connection-plugin">Connection.prototype.plugin()</a></li><li><a href="#connection_Connection-plugins">Connection.prototype.plugins</a></li><li><a href="#connection_Connection-port">Connection.prototype.port</a></li><li><a href="#connection_Connection-readyState">Connection.prototype.readyState</a></li><li><a href="#connection_Connection-set">Connection.prototype.set()</a></li><li><a href="#connection_Connection-startSession">Connection.prototype.startSession()</a></li><li><a href="#connection_Connection-useDb">Connection.prototype.useDb()</a></li><li><a href="#connection_Connection-user">Connection.prototype.user</a></li></ul><hr class="separate-api-elements"><h3 id="connection_Connection"><a href="#connection_Connection">Connection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">base
-<span class="method-type">&laquo;Mongoose&raquo;</span> a mongoose instance</li></ul><div><p>Connection constructor</p>
-
-<p>For practical reasons, a Connection equals a Db.</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-close"><a href="#connection_Connection-close">Connection.prototype.close()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[force]
-<span class="method-type">&laquo;Boolean&raquo;</span> optional</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> self</li></ul><div><p>Closes the connection</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-collection"><a href="#connection_Connection-collection">Connection.prototype.collection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> of the collection</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional collection options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Collection&raquo;</span> collection instance</li></ul><div><p>Retrieves a collection, creating it if not cached.</p>
-
-<p>Not typically needed by applications. Just talk to your collection through your model.</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-collections"><a href="#connection_Connection-collections">Connection.prototype.collections</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>A hash of the collections associated with this connection</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-config"><a href="#connection_Connection-config">Connection.prototype.config</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>A hash of the global options that are associated with this connection</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-createCollection"><a href="#connection_Connection-createCollection">Connection.prototype.createCollection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">collection
-<span class="method-type">&laquo;string&raquo;</span> The collection to create</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Db.html#createCollection">MongoDB driver docs</a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Helper for <code>createCollection()</code>. Will explicitly create the given collection with specified options. Used to create <a href="https://docs.mongodb.com/manual/core/capped-collections/">capped collections</a> and <a href="https://docs.mongodb.com/manual/core/views/">views</a> from mongoose.</p>
-
-<p>Options are passed down without modification to the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Db.html#createCollection">MongoDB driver's <code>createCollection()</code> function</a></p></div><hr class="separate-api-elements"><h3 id="connection_Connection-db"><a href="#connection_Connection-db">Connection.prototype.db</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The mongodb.Db instance, set when the connection is opened</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-deleteModel"><a href="#connection_Connection-deleteModel">Connection.prototype.deleteModel()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|RegExp&raquo;</span> if string, the name of the model to remove. If regexp, removes all models whose name matches the regexp.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> this</li></ul><div><p>Removes the model named <code>name</code> from this connection, if it exists. You can use this function to clean up any models you created in your tests to prevent OverwriteModelErrors.</p>
-
-<h4>Example:</h4>
-
-<pre><code>conn.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-built_in">console</span>.log(conn.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// Model object</span>
-conn.deleteModel(<span class="hljs-string">'User'</span>);
-<span class="hljs-built_in">console</span>.log(conn.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// undefined</span>
-
-<span class="hljs-comment">// Usually useful in a Mocha `afterEach()` hook</span>
-afterEach(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  conn.deleteModel(<span class="hljs-regexp">/.+/</span>); <span class="hljs-comment">// Delete every model</span>
-});</code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-dropCollection"><a href="#connection_Connection-dropCollection">Connection.prototype.dropCollection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">collection
-<span class="method-type">&laquo;string&raquo;</span> The collection to delete</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Helper for <code>dropCollection()</code>. Will delete the given collection, including all documents and indexes.</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-dropDatabase"><a href="#connection_Connection-dropDatabase">Connection.prototype.dropDatabase()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Helper for <code>dropDatabase()</code>. Deletes the given database, including all collections, documents, and indexes.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> conn = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>);
-<span class="hljs-comment">// Deletes the entire 'mydb' database</span>
-<span class="hljs-keyword">await</span> conn.dropDatabase();</code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-get"><a href="#connection_Connection-get">Connection.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Gets the value of the option <code>key</code>. Equivalent to <code>conn.options[key]</code></p>
-
-<h4>Example:</h4>
-
-<pre><code>conn.get(<span class="hljs-string">'test'</span>); <span class="hljs-comment">// returns the 'test' value</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-host"><a href="#connection_Connection-host">Connection.prototype.host</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The host name portion of the URI. If multiple hosts, such as a replica set, this will contain the first host name in the URI</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>).host; <span class="hljs-comment">// "localhost"</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-model"><a href="#connection_Connection-model">Connection.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|Function&raquo;</span> the model name or class extending Model</li><li class="param">[schema]
-<span class="method-type">&laquo;Schema&raquo;</span> a schema. necessary when defining a model</li><li class="param">[collection]
-<span class="method-type">&laquo;String&raquo;</span> name of mongodb collection (optional) if not given it will be induced from model name</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Model&raquo;</span> The compiled model</li></ul><div><p>Defines or retrieves a model.</p>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> db = mongoose.createConnection(..);
-db.model(<span class="hljs-string">'Venue'</span>, <span class="hljs-keyword">new</span> Schema(..));
-<span class="hljs-keyword">var</span> Ticket = db.model(<span class="hljs-string">'Ticket'</span>, <span class="hljs-keyword">new</span> Schema(..));
-<span class="hljs-keyword">var</span> Venue = db.model(<span class="hljs-string">'Venue'</span>);</code></pre>
-
-<p><em>When no <code>collection</code> argument is passed, Mongoose produces a collection name by passing the model <code>name</code> to the <a href="#utils_exports.toCollectionName">utils.toCollectionName</a> method. This method pluralizes the name. If you don't like this behavior, either pass a collection name or set your schemas collection name option.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { collection: <span class="hljs-string">'actor'</span> });
-
-<span class="hljs-comment">// or</span>
-
-schema.set(<span class="hljs-string">'collection'</span>, <span class="hljs-string">'actor'</span>);
-
-<span class="hljs-comment">// or</span>
-
-<span class="hljs-keyword">var</span> collectionName = <span class="hljs-string">'actor'</span>
-<span class="hljs-keyword">var</span> M = conn.model(<span class="hljs-string">'Actor'</span>, schema, collectionName)</code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-modelNames"><a href="#connection_Connection-modelNames">Connection.prototype.modelNames()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns an array of model names created on this connection.</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-name"><a href="#connection_Connection-name">Connection.prototype.name</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The name of the database this connection points to.</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>).name; <span class="hljs-comment">// "mydb"</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-openUri"><a href="#connection_Connection-openUri">Connection.prototype.openUri()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">uri
-<span class="method-type">&laquo;String&raquo;</span> The URI to connect with.</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Passed on to http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Opens the connection with a URI using <code>MongoClient.connect()</code>.</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-pass"><a href="#connection_Connection-pass">Connection.prototype.pass</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The password specified in the URI</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://val:psw@localhost:27017/mydb'</span>).pass; <span class="hljs-comment">// "psw"</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-plugin"><a href="#connection_Connection-plugin">Connection.prototype.plugin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> plugin callback</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> optional options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> this</li></ul><div><p>Declares a plugin executed on all schemas you pass to <code>conn.model()</code></p>
-
-<p>Equivalent to calling <code>.plugin(fn)</code> on each schema you create.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> db = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>);
-db.plugin(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Applied'</span>));
-db.plugins.length; <span class="hljs-comment">// 1</span>
-
-db.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({})); <span class="hljs-comment">// Prints "Applied"</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-plugins"><a href="#connection_Connection-plugins">Connection.prototype.plugins</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The plugins that will be applied to all models created on this connection.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> db = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>);
-db.plugin(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Applied'</span>));
-db.plugins.length; <span class="hljs-comment">// 1</span>
-
-db.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({})); <span class="hljs-comment">// Prints "Applied"</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-port"><a href="#connection_Connection-port">Connection.prototype.port</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The port portion of the URI. If multiple hosts, such as a replica set, this will contain the port from the first host name in the URI.</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>).port; <span class="hljs-comment">// 27017</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-readyState"><a href="#connection_Connection-readyState">Connection.prototype.readyState</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Connection ready state</p>
-
-<ul>
-<li>0 = disconnected</li>
-<li>1 = connected</li>
-<li>2 = connecting</li>
-<li>3 = disconnecting</li>
-</ul>
-
-<p>Each state change emits its associated event name.</p>
-
-<h4>Example</h4>
-
-<pre><code>conn.on(<span class="hljs-string">'connected'</span>, callback);
-conn.on(<span class="hljs-string">'disconnected'</span>, callback);</code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-set"><a href="#connection_Connection-set">Connection.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Any&raquo;</span> </li></ul><div><p>Sets the value of the option <code>key</code>. Equivalent to <code>conn.options[key] = val</code></p>
-
-<h2>Supported options include</h2>
-
-<ul>
-<li><code>maxTimeMS</code>: Set <a href="/docs/api.html#query_Query-maxTimeMS"><code>maxTimeMS</code></a> for all queries on this connection.</li>
-<li><code>useFindAndModify</code>: Set to <code>false</code> to work around the <a href="/docs/deprecations.html#-findandmodify-"><code>findAndModify()</code> deprecation warning</a></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code>conn.set(<span class="hljs-string">'test'</span>, <span class="hljs-string">'foo'</span>);
-conn.get(<span class="hljs-string">'test'</span>); <span class="hljs-comment">// 'foo'</span>
-conn.options.test; <span class="hljs-comment">// 'foo'</span></code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-startSession"><a href="#connection_Connection-startSession">Connection.prototype.startSession()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#startSession">mongodb driver options</a></li><ul style="margin-top: 0.5em"><li>[options.causalConsistency=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to disable causal consistency</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&lt;ClientSession&gt;&raquo;</span> promise that resolves to a MongoDB driver <code>ClientSession</code></li></ul><div><p><em>Requires MongoDB >= 3.6.0.</em> Starts a <a href="https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions">MongoDB session</a> for benefits like causal consistency, <a href="https://docs.mongodb.com/manual/core/retryable-writes/">retryable writes</a>, and <a href="http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html">transactions</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = <span class="hljs-keyword">await</span> conn.startSession();
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session });
-<span class="hljs-keyword">await</span> doc.remove();
-<span class="hljs-comment">// `doc` will always be null, even if reading from a replica set</span>
-<span class="hljs-comment">// secondary. Without causal consistency, it is possible to</span>
-<span class="hljs-comment">// get a doc back from the below query if the query reads from a</span>
-<span class="hljs-comment">// secondary that is experiencing replication lag.</span>
-doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session, readPreference: <span class="hljs-string">'secondary'</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="connection_Connection-useDb"><a href="#connection_Connection-useDb">Connection.prototype.useDb()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> The database name</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> New Connection Object</li></ul><div><p>Switches to a different database using the same connection pool.</p>
-
-<p>Returns a new connection object, with the new db.</p></div><hr class="separate-api-elements"><h3 id="connection_Connection-user"><a href="#connection_Connection-user">Connection.prototype.user</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The username specified in the URI</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://val:psw@localhost:27017/mydb'</span>).user; <span class="hljs-comment">// "val"</span></code></pre></div><hr class="separate-api"><h2 class="item-header" id="Document"><a href="#Document">Document</a></h2><ul><li><a href="#document_Document-$ignore">Document.prototype.$ignore()</a></li><li><a href="#document_Document-$isDefault">Document.prototype.$isDefault()</a></li><li><a href="#document_Document-$isDeleted">Document.prototype.$isDeleted()</a></li><li><a href="#document_Document-$isEmpty">Document.prototype.$isEmpty()</a></li><li><a href="#document_Document-$locals">Document.prototype.$locals</a></li><li><a href="#document_Document-$markValid">Document.prototype.$markValid()</a></li><li><a href="#document_Document-$session">Document.prototype.$session()</a></li><li><a href="#document_Document-$set">Document.prototype.$set()</a></li><li><a href="#document_Document-depopulate">Document.prototype.depopulate()</a></li><li><a href="#document_Document-directModifiedPaths">Document.prototype.directModifiedPaths()</a></li><li><a href="#document_Document-equals">Document.prototype.equals()</a></li><li><a href="#document_Document-errors">Document.prototype.errors</a></li><li><a href="#document_Document-execPopulate">Document.prototype.execPopulate()</a></li><li><a href="#document_Document-get">Document.prototype.get()</a></li><li><a href="#document_Document-id">Document.prototype.id</a></li><li><a href="#document_Document-init">Document.prototype.init()</a></li><li><a href="#document_Document-inspect">Document.prototype.inspect()</a></li><li><a href="#document_Document-invalidate">Document.prototype.invalidate()</a></li><li><a href="#document_Document-isDirectModified">Document.prototype.isDirectModified()</a></li><li><a href="#document_Document-isDirectSelected">Document.prototype.isDirectSelected()</a></li><li><a href="#document_Document-isInit">Document.prototype.isInit()</a></li><li><a href="#document_Document-isModified">Document.prototype.isModified()</a></li><li><a href="#document_Document-isNew">Document.prototype.isNew</a></li><li><a href="#document_Document-isSelected">Document.prototype.isSelected()</a></li><li><a href="#document_Document-markModified">Document.prototype.markModified()</a></li><li><a href="#document_Document-modifiedPaths">Document.prototype.modifiedPaths()</a></li><li><a href="#document_Document-overwrite">Document.prototype.overwrite()</a></li><li><a href="#document_Document-populate">Document.prototype.populate()</a></li><li><a href="#document_Document-populated">Document.prototype.populated()</a></li><li><a href="#document_Document-replaceOne">Document.prototype.replaceOne()</a></li><li><a href="#document_Document-save">Document.prototype.save()</a></li><li><a href="#document_Document-schema">Document.prototype.schema</a></li><li><a href="#document_Document-set">Document.prototype.set()</a></li><li><a href="#document_Document-toJSON">Document.prototype.toJSON()</a></li><li><a href="#document_Document-toObject">Document.prototype.toObject()</a></li><li><a href="#document_Document-toString">Document.prototype.toString()</a></li><li><a href="#document_Document-unmarkModified">Document.prototype.unmarkModified()</a></li><li><a href="#document_Document-update">Document.prototype.update()</a></li><li><a href="#document_Document-updateOne">Document.prototype.updateOne()</a></li><li><a href="#document_Document-validate">Document.prototype.validate()</a></li><li><a href="#document_Document-validateSync">Document.prototype.validateSync()</a></li></ul><hr class="separate-api-elements"><h3 id="document_Document-$ignore"><a href="#document_Document-$ignore">Document.prototype.$ignore()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the path to ignore</li></ul><div><p>Don't run validation on this path or persist changes to this path.</p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.foo = <span class="hljs-literal">null</span>;
-doc.$ignore(<span class="hljs-string">'foo'</span>);
-doc.save(); <span class="hljs-comment">// changes to foo will not be persisted and validators won't be run</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-$isDefault"><a href="#document_Document-$isDefault">Document.prototype.$isDefault()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if a path is set to its default.</p>
-
-<h4>Example</h4>
-
-<pre><code>MyModel = mongoose.model(<span class="hljs-string">'test'</span>, { name: { type: <span class="hljs-built_in">String</span>, <span class="hljs-keyword">default</span>: <span class="hljs-string">'Val '</span>} });
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> MyModel();
-m.$isDefault(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-$isDeleted"><a href="#document_Document-$isDeleted">Document.prototype.$isDeleted()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[val]
-<span class="method-type">&laquo;Boolean&raquo;</span> optional, overrides whether mongoose thinks the doc is deleted</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> whether mongoose thinks this doc is deleted.</li></ul><div><p>Getter/setter, determines whether the document was removed or not.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.remove(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-  product.$isDeleted(); <span class="hljs-comment">// true</span>
-  product.remove(); <span class="hljs-comment">// no-op, doesn't send anything to the db</span>
-
-  product.$isDeleted(<span class="hljs-literal">false</span>);
-  product.$isDeleted(); <span class="hljs-comment">// false</span>
-  product.remove(); <span class="hljs-comment">// will execute a remove against the db</span>
-})</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-$isEmpty"><a href="#document_Document-$isEmpty">Document.prototype.$isEmpty()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if the given path is nullish or only contains empty objects. Useful for determining whether this subdoc will get stripped out by the <a href="/docs/guide.html#minimize">minimize option</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ nested: { foo: <span class="hljs-built_in">String</span> } });
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({});
-doc.$isEmpty(<span class="hljs-string">'nested'</span>); <span class="hljs-comment">// true</span>
-doc.nested.$isEmpty(); <span class="hljs-comment">// true</span>
-
-doc.nested.foo = <span class="hljs-string">'bar'</span>;
-doc.$isEmpty(<span class="hljs-string">'nested'</span>); <span class="hljs-comment">// false</span>
-doc.nested.$isEmpty(); <span class="hljs-comment">// false</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-$locals"><a href="#document_Document-$locals">Document.prototype.$locals</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Empty object that you can use for storing properties on the document. This is handy for passing data to middleware without conflicting with Mongoose internals.</p>
-
-<h4>Example:</h4>
-
-<pre><code>schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Mongoose will set `isNew` to `false` if `save()` succeeds</span>
-  <span class="hljs-keyword">this</span>.$locals.wasNew = <span class="hljs-keyword">this</span>.isNew;
-});
-
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Prints true if `isNew` was set before `save()`</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>.$locals.wasNew);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-$markValid"><a href="#document_Document-$markValid">Document.prototype.$markValid()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the field to mark as valid</li></ul><div><p>Marks a path as valid, removing existing validation errors.</p></div><hr class="separate-api-elements"><h3 id="document_Document-$session"><a href="#document_Document-$session">Document.prototype.$session()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[session]
-<span class="method-type">&laquo;ClientSession&raquo;</span> overwrite the current session</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ClientSession&raquo;</span> </li></ul><div><p>Getter/setter around the session associated with this document. Used to automatically set <code>session</code> if you <code>save()</code> a doc that you got from a query with an associated session.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = MyModel.startSession();
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> MyModel.findOne().session(session);
-doc.$session() === session; <span class="hljs-comment">// true</span>
-doc.$session(<span class="hljs-literal">null</span>);
-doc.$session() === <span class="hljs-literal">null</span>; <span class="hljs-comment">// true</span></code></pre>
-
-<p>If this is a top-level document, setting the session propagates to all child docs.</p></div><hr class="separate-api-elements"><h3 id="document_Document-$set"><a href="#document_Document-$set">Document.prototype.$set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object&raquo;</span> path or object of key/vals to set</li><li class="param">val
-<span class="method-type">&laquo;Any&raquo;</span> the value to set</li><li class="param">[type]
-<span class="method-type">&laquo;Schema|String|Number|Buffer|*&raquo;</span> optionally specify a type for &quot;on-the-fly&quot; attributes</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optionally specify options that modify the behavior of the set</li></ul><div><p>Alias for <code>set()</code>, used internally to avoid conflicts</p></div><hr class="separate-api-elements"><h3 id="document_Document-depopulate"><a href="#document_Document-depopulate">Document.prototype.depopulate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Document&raquo;</span> this</li></ul><div><p>Takes a populated field and returns it to its unpopulated state.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findOne().populate(<span class="hljs-string">'author'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.author.name); <span class="hljs-comment">// Dr.Seuss</span>
-  <span class="hljs-built_in">console</span>.log(doc.depopulate(<span class="hljs-string">'author'</span>));
-  <span class="hljs-built_in">console</span>.log(doc.author); <span class="hljs-comment">// '5144cf8050f071d979c118a7'</span>
-})</code></pre>
-
-<p>If the path was not populated, this is a no-op.</p></div><hr class="separate-api-elements"><h3 id="document_Document-directModifiedPaths"><a href="#document_Document-directModifiedPaths">Document.prototype.directModifiedPaths()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns the list of paths that have been directly modified. A direct modified path is a path that you explicitly set, whether via <code>doc.foo = 'bar'</code>, <code>Object.assign(doc, { foo: 'bar' })</code>, or <code>doc.set('foo', 'bar')</code>.</p>
-
-<p>A path <code>a</code> may be in <code>modifiedPaths()</code> but not in <code>directModifiedPaths()</code> because a child of <code>a</code> was directly modified.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ foo: <span class="hljs-built_in">String</span>, nested: { bar: <span class="hljs-built_in">String</span> } });
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">await</span> Model.create({ foo: <span class="hljs-string">'original'</span>, nested: { bar: <span class="hljs-string">'original'</span> } });
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Model.findOne();
-doc.nested.bar = <span class="hljs-string">'modified'</span>;
-doc.directModifiedPaths(); <span class="hljs-comment">// ['nested.bar']</span>
-doc.modifiedPaths(); <span class="hljs-comment">// ['nested', 'nested.bar']</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-equals"><a href="#document_Document-equals">Document.prototype.equals()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Document&raquo;</span> a document to compare</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if the Document stores the same data as doc.</p>
-
-<p>Documents are considered equal when they have matching <code>_id</code>s, unless neither document has an <code>_id</code>, in which case this function falls back to using <code>deepEqual()</code>.</p></div><hr class="separate-api-elements"><h3 id="document_Document-errors"><a href="#document_Document-errors">Document.prototype.errors</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Hash containing current validation errors.</p></div><hr class="separate-api-elements"><h3 id="document_Document-execPopulate"><a href="#document_Document-execPopulate">Document.prototype.execPopulate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback. If specified, a promise will <strong>not</strong> be returned</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> promise that resolves to the document when population is done</li></ul><div><p>Explicitly executes population and returns a promise. Useful for ES2015 integration.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> promise = doc.
-  populate(<span class="hljs-string">'company'</span>).
-  populate({
-    path: <span class="hljs-string">'notes'</span>,
-    match: <span class="hljs-regexp">/airline/</span>,
-    select: <span class="hljs-string">'text'</span>,
-    model: <span class="hljs-string">'modelName'</span>
-    options: opts
-  }).
-  execPopulate();
-
-<span class="hljs-comment">// summary</span>
-doc.execPopulate().then(resolve, reject);</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-get"><a href="#document_Document-get">Document.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[type]
-<span class="method-type">&laquo;Schema|String|Number|Buffer|*&raquo;</span> optionally specify a type for on-the-fly attributes</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.virtuals=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> Apply virtuals before getting this path</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> If false, skip applying getters and just get the raw value</li></ul></ul><div><p>Returns the value of a path.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// path</span>
-doc.get(<span class="hljs-string">'age'</span>) <span class="hljs-comment">// 47</span>
-
-<span class="hljs-comment">// dynamic casting to a string</span>
-doc.get(<span class="hljs-string">'age'</span>, <span class="hljs-built_in">String</span>) <span class="hljs-comment">// "47"</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-id"><a href="#document_Document-id">Document.prototype.id</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The string version of this documents _id.</p>
-
-<h4>Note:</h4>
-
-<p>This getter exists on all documents by default. The getter can be disabled by setting the <code>id</code> <a href="/docs/guide.html#id">option</a> of its <code>Schema</code> to false at construction time.</p>
-
-<pre><code><span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { id: <span class="hljs-literal">false</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-init"><a href="#document_Document-init">Document.prototype.init()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> document returned by mongo</li></ul><div><p>Initializes the document without setters or marking anything modified.</p>
-
-<p>Called internally after a document is returned from mongodb. Normally, you do <strong>not</strong> need to call this function on your own.</p>
-
-<p>This function triggers <code>init</code> <a href="/docs/middleware.html">middleware</a>. Note that <code>init</code> hooks are <a href="/docs/middleware.html#synchronous">synchronous</a>.</p></div><hr class="separate-api-elements"><h3 id="document_Document-inspect"><a href="#document_Document-inspect">Document.prototype.inspect()</a></h3><div><p>Helper for console.log</p></div><hr class="separate-api-elements"><h3 id="document_Document-invalidate"><a href="#document_Document-invalidate">Document.prototype.invalidate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the field to invalidate</li><li class="param">errorMsg
-<span class="method-type">&laquo;String|Error&raquo;</span> the error which states the reason <code>path</code> was invalid</li><li class="param">value
-<span class="method-type">&laquo;Object|String|Number|any&raquo;</span> optional invalid value</li><li class="param">[kind]
-<span class="method-type">&laquo;String&raquo;</span> optional <code>kind</code> property for the error</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ValidationError&raquo;</span> the current ValidationError, with all currently invalidated paths</li></ul><div><p>Marks a path as invalid, causing validation to fail.</p>
-
-<p>The <code>errorMsg</code> argument will become the message of the <code>ValidationError</code>.</p>
-
-<p>The <code>value</code> argument (if passed) will be available through the <code>ValidationError.value</code> property.</p>
-
-<pre><code>doc.invalidate(<span class="hljs-string">'size'</span>, <span class="hljs-string">'must be less than 20'</span>, <span class="hljs-number">14</span>);
-
-doc.validate(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(err)
-  <span class="hljs-comment">// prints</span>
-  { message: <span class="hljs-string">'Validation failed'</span>,
-    name: <span class="hljs-string">'ValidationError'</span>,
-    errors:
-     { size:
-        { message: <span class="hljs-string">'must be less than 20'</span>,
-          name: <span class="hljs-string">'ValidatorError'</span>,
-          path: <span class="hljs-string">'size'</span>,
-          type: <span class="hljs-string">'user defined'</span>,
-          value: <span class="hljs-number">14</span> } } }
-})</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-isDirectModified"><a href="#document_Document-isDirectModified">Document.prototype.isDirectModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if <code>path</code> was directly set and modified, else false.</p>
-
-<h4>Example</h4>
-
-<pre><code>doc.set(<span class="hljs-string">'documents.0.title'</span>, <span class="hljs-string">'changed'</span>);
-doc.isDirectModified(<span class="hljs-string">'documents.0.title'</span>) <span class="hljs-comment">// true</span>
-doc.isDirectModified(<span class="hljs-string">'documents'</span>) <span class="hljs-comment">// false</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-isDirectSelected"><a href="#document_Document-isDirectSelected">Document.prototype.isDirectSelected()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if <code>path</code> was explicitly selected. If no projection, always returns true.</p>
-
-<h4>Example</h4>
-
-<pre><code>Thing.findOne().select(<span class="hljs-string">'nested.name'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-   doc.isDirectSelected(<span class="hljs-string">'nested.name'</span>) <span class="hljs-comment">// true</span>
-   doc.isDirectSelected(<span class="hljs-string">'nested.otherName'</span>) <span class="hljs-comment">// false</span>
-   doc.isDirectSelected(<span class="hljs-string">'nested'</span>)  <span class="hljs-comment">// false</span>
-})</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-isInit"><a href="#document_Document-isInit">Document.prototype.isInit()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if <code>path</code> was initialized.</p></div><hr class="separate-api-elements"><h3 id="document_Document-isModified"><a href="#document_Document-isModified">Document.prototype.isModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> optional</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if this document was modified, else false.</p>
-
-<p>If <code>path</code> is given, checks if a path or any full path containing <code>path</code> as part of its path chain has been modified.</p>
-
-<h4>Example</h4>
-
-<pre><code>doc.set(<span class="hljs-string">'documents.0.title'</span>, <span class="hljs-string">'changed'</span>);
-doc.isModified()                      <span class="hljs-comment">// true</span>
-doc.isModified(<span class="hljs-string">'documents'</span>)           <span class="hljs-comment">// true</span>
-doc.isModified(<span class="hljs-string">'documents.0.title'</span>)   <span class="hljs-comment">// true</span>
-doc.isModified(<span class="hljs-string">'documents otherProp'</span>) <span class="hljs-comment">// true</span>
-doc.isDirectModified(<span class="hljs-string">'documents'</span>)     <span class="hljs-comment">// false</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-isNew"><a href="#document_Document-isNew">Document.prototype.isNew</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Boolean flag specifying if the document is new.</p></div><hr class="separate-api-elements"><h3 id="document_Document-isSelected"><a href="#document_Document-isSelected">Document.prototype.isSelected()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if <code>path</code> was selected in the source query which initialized this document.</p>
-
-<h4>Example</h4>
-
-<pre><code>Thing.findOne().select(<span class="hljs-string">'name'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-   doc.isSelected(<span class="hljs-string">'name'</span>) <span class="hljs-comment">// true</span>
-   doc.isSelected(<span class="hljs-string">'age'</span>)  <span class="hljs-comment">// false</span>
-})</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-markModified"><a href="#document_Document-markModified">Document.prototype.markModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the path to mark modified</li><li class="param">[scope]
-<span class="method-type">&laquo;Document&raquo;</span> the scope to run validators with</li></ul><div><p>Marks the path as having pending changes to write to the db.</p>
-
-<p><em>Very helpful when using <a href="./schematypes.html#mixed">Mixed</a> types.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.mixed.type = <span class="hljs-string">'changed'</span>;
-doc.markModified(<span class="hljs-string">'mixed.type'</span>);
-doc.save() <span class="hljs-comment">// changes to mixed.type are now persisted</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-modifiedPaths"><a href="#document_Document-modifiedPaths">Document.prototype.modifiedPaths()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.includeChildren=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns children of modified paths as well. For example, if false, the list of modified paths for <code>doc.colors = { primary: &#39;blue&#39; };</code> will <strong>not</strong> contain <code>colors.primary</code>. If true, <code>modifiedPaths()</code> will return an array that contains <code>colors.primary</code>.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns the list of paths that have been modified.</p></div><hr class="separate-api-elements"><h3 id="document_Document-overwrite"><a href="#document_Document-overwrite">Document.prototype.overwrite()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;Object&raquo;</span> the object to overwrite this document with</li></ul><div><p>Overwrite all values in this document with the values of <code>obj</code>, except for immutable properties. Behaves similarly to <code>set()</code>, except for it unsets all properties that aren't in <code>obj</code>.</p></div><hr class="separate-api-elements"><h3 id="document_Document-populate"><a href="#document_Document-populate">Document.prototype.populate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String|Object&raquo;</span> The path to populate or an options object</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> When passed, population is invoked</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Document&raquo;</span> this</li></ul><div><p>Populates document references, executing the <code>callback</code> when complete. If you want to use promises instead, use this function with <a href="#document_Document-execPopulate"><code>execPopulate()</code></a></p>
-
-<h4>Example:</h4>
-
-<pre><code>doc
-.populate(<span class="hljs-string">'company'</span>)
-.populate({
-  path: <span class="hljs-string">'notes'</span>,
-  match: <span class="hljs-regexp">/airline/</span>,
-  select: <span class="hljs-string">'text'</span>,
-  model: <span class="hljs-string">'modelName'</span>
-  options: opts
-}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-  assert(doc._id === user._id) <span class="hljs-comment">// the document itself is passed</span>
-})
-
-<span class="hljs-comment">// summary</span>
-doc.populate(path)                   <span class="hljs-comment">// not executed</span>
-doc.populate(options);               <span class="hljs-comment">// not executed</span>
-doc.populate(path, callback)         <span class="hljs-comment">// executed</span>
-doc.populate(options, callback);     <span class="hljs-comment">// executed</span>
-doc.populate(callback);              <span class="hljs-comment">// executed</span>
-doc.populate(options).execPopulate() <span class="hljs-comment">// executed, returns promise</span></code></pre>
-
-<h4>NOTE:</h4>
-
-<p>Population does not occur unless a <code>callback</code> is passed <em>or</em> you explicitly call <code>execPopulate()</code>. Passing the same path a second time will overwrite the previous path options. See <a href="#model_Model.populate">Model.populate()</a> for explaination of options.</p></div><hr class="separate-api-elements"><h3 id="document_Document-populated"><a href="#document_Document-populated">Document.prototype.populated()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array,ObjectId,Number,Buffer,String,undefined&raquo;</span> </li></ul><div><p>Gets _id(s) used during population of the given <code>path</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findOne().populate(<span class="hljs-string">'author'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.author.name)         <span class="hljs-comment">// Dr.Seuss</span>
-  <span class="hljs-built_in">console</span>.log(doc.populated(<span class="hljs-string">'author'</span>)) <span class="hljs-comment">// '5144cf8050f071d979c118a7'</span>
-})</code></pre>
-
-<p>If the path was not populated, undefined is returned.</p></div><hr class="separate-api-elements"><h3 id="document_Document-replaceOne"><a href="#document_Document-replaceOne">Document.prototype.replaceOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Sends a replaceOne command with this document <code>_id</code> as the query selector.</p>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li>same as in <a href="#model_Model.replaceOne">Model.replaceOne</a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="document_Document-save"><a href="#document_Document-save">Document.prototype.save()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> options optional options</li><ul style="margin-top: 0.5em"><li>[options.safe]
-<span class="method-type">&laquo;Object&raquo;</span> (DEPRECATED) overrides <a href="http://mongoosejs.com//docs/guide.html#safe">schema&#39;s safe option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.validateBeforeSave]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to save without validating.</li></ul><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns undefined if used with callback or a Promise otherwise.</li></ul><div><p>Saves this document.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.sold = <span class="hljs-built_in">Date</span>.now();
-product.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-})</code></pre>
-
-<p>The callback will receive two parameters</p>
-
-<ol>
-<li><code>err</code> if an error occurred</li>
-<li><code>product</code> which is the saved <code>product</code></li>
-</ol>
-
-<p>As an extra measure of flow control, save will return a Promise.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.save().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">product</span>) </span>{
-   ...
-});</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-schema"><a href="#document_Document-schema">Document.prototype.schema</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The documents schema.</p></div><hr class="separate-api-elements"><h3 id="document_Document-set"><a href="#document_Document-set">Document.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object&raquo;</span> path or object of key/vals to set</li><li class="param">val
-<span class="method-type">&laquo;Any&raquo;</span> the value to set</li><li class="param">[type]
-<span class="method-type">&laquo;Schema|String|Number|Buffer|*&raquo;</span> optionally specify a type for &quot;on-the-fly&quot; attributes</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optionally specify options that modify the behavior of the set</li></ul><div><p>Sets the value of a path, or many paths.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// path, value</span>
-doc.set(path, value)
-
-<span class="hljs-comment">// object</span>
-doc.set({
-    path  : value
-  , path2 : {
-       path  : value
-    }
-})
-
-<span class="hljs-comment">// on-the-fly cast to number</span>
-doc.set(path, value, <span class="hljs-built_in">Number</span>)
-
-<span class="hljs-comment">// on-the-fly cast to string</span>
-doc.set(path, value, <span class="hljs-built_in">String</span>)
-
-<span class="hljs-comment">// changing strict mode behavior</span>
-doc.set(path, value, { strict: <span class="hljs-literal">false</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-toJSON"><a href="#document_Document-toJSON">Document.prototype.toJSON()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>The return value of this method is used in calls to JSON.stringify(doc).</p>
-
-<p>This method accepts the same options as <a href="#document_Document-toObject">Document#toObject</a>. To apply the options to every document of your schema by default, set your <a href="#schema_Schema">schemas</a> <code>toJSON</code> option to the same argument.</p>
-
-<pre><code>schema.set(<span class="hljs-string">'toJSON'</span>, { virtuals: <span class="hljs-literal">true</span> })</code></pre>
-
-<p>See <a href="/docs/guide.html#toJSON">schema options</a> for details.</p></div><hr class="separate-api-elements"><h3 id="document_Document-toObject"><a href="#document_Document-toObject">Document.prototype.toObject()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, apply all getters, including virtuals</li></ul><ul style="margin-top: 0.5em"><li>[options.virtuals=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, apply virtuals. Use <code>{ getters: true, virtuals: false }</code> to just apply getters, not virtuals</li></ul><ul style="margin-top: 0.5em"><li>[options.minimize=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, omit any empty objects from the output</li></ul><ul style="margin-top: 0.5em"><li>[options.transform=null]
-<span class="method-type">&laquo;Function|null&raquo;</span> if set, mongoose will call this function to allow you to transform the returned object</li></ul><ul style="margin-top: 0.5em"><li>[options.depopulate=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, replace any conventionally populated paths with the original id in the output. Has no affect on virtual populated paths.</li></ul><ul style="margin-top: 0.5em"><li>[options.versionKey=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> if false, exclude the version key (<code>__v</code> by default) from the output</li></ul><ul style="margin-top: 0.5em"><li>[options.flattenMaps=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, convert Maps to POJOs. Useful if you want to <code>JSON.stringify()</code> the result of <code>toObject()</code>.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> js object</li></ul><div><p>Converts this document into a plain javascript object, ready for storage in MongoDB.</p>
-
-<p>Buffers are converted to instances of <a href="http://mongodb.github.com/node-mongodb-native/api-bson-generated/binary.html">mongodb.Binary</a> for proper storage.</p>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>getters</code> apply all getters (path and virtual getters), defaults to false</li>
-<li><code>virtuals</code> apply virtual getters (can override <code>getters</code> option), defaults to false</li>
-<li><code>minimize</code> remove empty objects (defaults to true)</li>
-<li><code>transform</code> a transform function to apply to the resulting document before returning</li>
-<li><code>depopulate</code> depopulate any populated paths, replacing them with their original refs (defaults to false)</li>
-<li><code>versionKey</code> whether to include the version key (defaults to true)</li>
-</ul>
-
-<h4>Getters/Virtuals</h4>
-
-<p>Example of only applying path getters</p>
-
-<pre><code>doc.toObject({ getters: <span class="hljs-literal">true</span>, virtuals: <span class="hljs-literal">false</span> })</code></pre>
-
-<p>Example of only applying virtual getters</p>
-
-<pre><code>doc.toObject({ virtuals: <span class="hljs-literal">true</span> })</code></pre>
-
-<p>Example of applying both path and virtual getters</p>
-
-<pre><code>doc.toObject({ getters: <span class="hljs-literal">true</span> })</code></pre>
-
-<p>To apply these options to every document of your schema by default, set your <a href="#schema_Schema">schemas</a> <code>toObject</code> option to the same argument.</p>
-
-<pre><code>schema.set(<span class="hljs-string">'toObject'</span>, { virtuals: <span class="hljs-literal">true</span> })</code></pre>
-
-<h4>Transform</h4>
-
-<p>We may need to perform a transformation of the resulting object based on some criteria, say to remove some sensitive information or return a custom object. In this case we set the optional <code>transform</code> function.</p>
-
-<p>Transform functions receive three arguments</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{}</code></pre>
-
-<ul>
-<li><code>doc</code> The mongoose document which is being converted</li>
-<li><code>ret</code> The plain object representation which has been converted</li>
-<li><code>options</code> The options in use (either schema options or the options passed inline)</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// specify the transform schema option</span>
-<span class="hljs-keyword">if</span> (!schema.options.toObject) schema.options.toObject = {};
-schema.options.toObject.transform = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-comment">// remove the _id of every document before returning the result</span>
-  <span class="hljs-keyword">delete</span> ret._id;
-  <span class="hljs-keyword">return</span> ret;
-}
-
-<span class="hljs-comment">// without the transformation in the schema</span>
-doc.toObject(); <span class="hljs-comment">// { _id: 'anId', name: 'Wreck-it Ralph' }</span>
-
-<span class="hljs-comment">// with the transformation</span>
-doc.toObject(); <span class="hljs-comment">// { name: 'Wreck-it Ralph' }</span></code></pre>
-
-<p>With transformations we can do a lot more than remove properties. We can even return completely new customized objects:</p>
-
-<pre><code><span class="hljs-keyword">if</span> (!schema.options.toObject) schema.options.toObject = {};
-schema.options.toObject.transform = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-keyword">return</span> { movie: ret.name }
-}
-
-<span class="hljs-comment">// without the transformation in the schema</span>
-doc.toObject(); <span class="hljs-comment">// { _id: 'anId', name: 'Wreck-it Ralph' }</span>
-
-<span class="hljs-comment">// with the transformation</span>
-doc.toObject(); <span class="hljs-comment">// { movie: 'Wreck-it Ralph' }</span></code></pre>
-
-<p><em>Note: if a transform function returns <code>undefined</code>, the return value will be ignored.</em></p>
-
-<p>Transformations may also be applied inline, overridding any transform set in the options:</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">xform</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-keyword">return</span> { inline: ret.name, custom: <span class="hljs-literal">true</span> }
-}
-
-<span class="hljs-comment">// pass the transform as an inline option</span>
-doc.toObject({ transform: xform }); <span class="hljs-comment">// { inline: 'Wreck-it Ralph', custom: true }</span></code></pre>
-
-<p>If you want to skip transformations, use <code>transform: false</code>:</p>
-
-<pre><code><span class="hljs-keyword">if</span> (!schema.options.toObject) schema.options.toObject = {};
-schema.options.toObject.hide = <span class="hljs-string">'_id'</span>;
-schema.options.toObject.transform = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-keyword">if</span> (options.hide) {
-    options.hide.split(<span class="hljs-string">' '</span>).forEach(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">prop</span>) </span>{
-      <span class="hljs-keyword">delete</span> ret[prop];
-    });
-  }
-  <span class="hljs-keyword">return</span> ret;
-}
-
-<span class="hljs-keyword">var</span> doc = <span class="hljs-keyword">new</span> Doc({ _id: <span class="hljs-string">'anId'</span>, secret: <span class="hljs-number">47</span>, name: <span class="hljs-string">'Wreck-it Ralph'</span> });
-doc.toObject();                                        <span class="hljs-comment">// { secret: 47, name: 'Wreck-it Ralph' }</span>
-doc.toObject({ hide: <span class="hljs-string">'secret _id'</span>, transform: <span class="hljs-literal">false</span> });<span class="hljs-comment">// { _id: 'anId', secret: 47, name: 'Wreck-it Ralph' }</span>
-doc.toObject({ hide: <span class="hljs-string">'secret _id'</span>, transform: <span class="hljs-literal">true</span> }); <span class="hljs-comment">// { name: 'Wreck-it Ralph' }</span></code></pre>
-
-<p>Transforms are applied <em>only to the document and are not applied to sub-documents</em>.</p>
-
-<p>Transforms, like all of these options, are also available for <code>toJSON</code>.</p>
-
-<p>See <a href="/docs/guide.html#toObject">schema options</a> for some more details.</p>
-
-<p><em>During save, no custom options are applied to the document before being sent to the database.</em></p></div><hr class="separate-api-elements"><h3 id="document_Document-toString"><a href="#document_Document-toString">Document.prototype.toString()</a></h3><div><p>Helper for console.log</p></div><hr class="separate-api-elements"><h3 id="document_Document-unmarkModified"><a href="#document_Document-unmarkModified">Document.prototype.unmarkModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the path to unmark modified</li></ul><div><p>Clears the modified state on the specified path.</p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.foo = <span class="hljs-string">'bar'</span>;
-doc.unmarkModified(<span class="hljs-string">'foo'</span>);
-doc.save(); <span class="hljs-comment">// changes to foo will not be persisted</span></code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-update"><a href="#document_Document-update">Document.prototype.update()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Sends an update command with this document <code>_id</code> as the query selector.</p>
-
-<h4>Example:</h4>
-
-<pre><code>weirdCar.update({$inc: {wheels:<span class="hljs-number">1</span>}}, { w: <span class="hljs-number">1</span> }, callback);</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li>same as in <a href="#model_Model.update">Model.update</a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="document_Document-updateOne"><a href="#document_Document-updateOne">Document.prototype.updateOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Sends an updateOne command with this document <code>_id</code> as the query selector.</p>
-
-<h4>Example:</h4>
-
-<pre><code>weirdCar.updateOne({$inc: {wheels:<span class="hljs-number">1</span>}}, { w: <span class="hljs-number">1</span> }, callback);</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li>same as in <a href="#model_Model.updateOne">Model.updateOne</a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="document_Document-validate"><a href="#document_Document-validate">Document.prototype.validate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">optional
-<span class="method-type">&laquo;Object&raquo;</span> options internal options</li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> optional callback called after validation completes, passing an error if one occurred</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> Promise</li></ul><div><p>Executes registered validation rules for this document.</p>
-
-<h4>Note:</h4>
-
-<p>This method is called <code>pre</code> save and if a validation rule is violated, <a href="#model_Model-save">save</a> is aborted and the error is returned to your <code>callback</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.validate(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) handleError(err);
-  <span class="hljs-keyword">else</span> <span class="hljs-comment">// validation passed</span>
-});</code></pre></div><hr class="separate-api-elements"><h3 id="document_Document-validateSync"><a href="#document_Document-validateSync">Document.prototype.validateSync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">pathsToValidate
-<span class="method-type">&laquo;Array|string&raquo;</span> only validate the given paths</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ValidationError,undefined&raquo;</span> ValidationError if there are errors during validation, or undefined if there is no error.</li></ul><div><p>Executes registered validation rules (skipping asynchronous validators) for this document.</p>
-
-<h4>Note:</h4>
-
-<p>This method is useful if you need synchronous validation.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> err = doc.validateSync();
-<span class="hljs-keyword">if</span> ( err ){
-  handleError( err );
-} <span class="hljs-keyword">else</span> {
-  <span class="hljs-comment">// validation passed</span>
-}</code></pre></div><hr class="separate-api"><h2 class="item-header" id="Model"><a href="#Model">Model</a></h2><ul><li><a href="#model_Model">Model()</a></li><li><a href="#model_Model.aggregate">Model.aggregate()</a></li><li><a href="#model_Model.bulkWrite">Model.bulkWrite()</a></li><li><a href="#model_Model.count">Model.count()</a></li><li><a href="#model_Model.countDocuments">Model.countDocuments()</a></li><li><a href="#model_Model.create">Model.create()</a></li><li><a href="#model_Model.createCollection">Model.createCollection()</a></li><li><a href="#model_Model.createIndexes">Model.createIndexes()</a></li><li><a href="#model_Model.deleteMany">Model.deleteMany()</a></li><li><a href="#model_Model.deleteOne">Model.deleteOne()</a></li><li><a href="#model_Model.discriminator">Model.discriminator()</a></li><li><a href="#model_Model.distinct">Model.distinct()</a></li><li><a href="#model_Model.ensureIndexes">Model.ensureIndexes()</a></li><li><a href="#model_Model.estimatedDocumentCount">Model.estimatedDocumentCount()</a></li><li><a href="#model_Model-events">Model.events</a></li><li><a href="#model_Model.exists">Model.exists()</a></li><li><a href="#model_Model.find">Model.find()</a></li><li><a href="#model_Model.findById">Model.findById()</a></li><li><a href="#model_Model.findByIdAndDelete">Model.findByIdAndDelete()</a></li><li><a href="#model_Model.findByIdAndRemove">Model.findByIdAndRemove()</a></li><li><a href="#model_Model.findByIdAndUpdate">Model.findByIdAndUpdate()</a></li><li><a href="#model_Model.findOne">Model.findOne()</a></li><li><a href="#model_Model.findOneAndDelete">Model.findOneAndDelete()</a></li><li><a href="#model_Model.findOneAndRemove">Model.findOneAndRemove()</a></li><li><a href="#model_Model.findOneAndReplace">Model.findOneAndReplace()</a></li><li><a href="#model_Model.findOneAndUpdate">Model.findOneAndUpdate()</a></li><li><a href="#model_Model.geoSearch">Model.geoSearch()</a></li><li><a href="#model_Model.hydrate">Model.hydrate()</a></li><li><a href="#model_Model.init">Model.init()</a></li><li><a href="#model_Model.insertMany">Model.insertMany()</a></li><li><a href="#model_Model.listIndexes">Model.listIndexes()</a></li><li><a href="#model_Model.mapReduce">Model.mapReduce()</a></li><li><a href="#model_Model.populate">Model.populate()</a></li><li><a href="#model_Model-$where">Model.prototype.$where</a></li><li><a href="#model_Model-$where">Model.prototype.$where()</a></li><li><a href="#model_Model-base">Model.prototype.base</a></li><li><a href="#model_Model-baseModelName">Model.prototype.baseModelName</a></li><li><a href="#model_Model-collection">Model.prototype.collection</a></li><li><a href="#model_Model-db">Model.prototype.db</a></li><li><a href="#model_Model-delete">Model.prototype.delete</a></li><li><a href="#model_Model-deleteOne">Model.prototype.deleteOne()</a></li><li><a href="#model_Model-discriminators">Model.prototype.discriminators</a></li><li><a href="#model_Model-increment">Model.prototype.increment()</a></li><li><a href="#model_Model-model">Model.prototype.model()</a></li><li><a href="#model_Model-modelName">Model.prototype.modelName</a></li><li><a href="#model_Model-remove">Model.prototype.remove()</a></li><li><a href="#model_Model-save">Model.prototype.save()</a></li><li><a href="#model_Model-schema">Model.prototype.schema</a></li><li><a href="#model_Model.remove">Model.remove()</a></li><li><a href="#model_Model.replaceOne">Model.replaceOne()</a></li><li><a href="#model_Model.startSession">Model.startSession()</a></li><li><a href="#model_Model.syncIndexes">Model.syncIndexes()</a></li><li><a href="#model_Model.translateAliases">Model.translateAliases()</a></li><li><a href="#model_Model.update">Model.update()</a></li><li><a href="#model_Model.updateMany">Model.updateMany()</a></li><li><a href="#model_Model.updateOne">Model.updateOne()</a></li><li><a href="#model_Model.watch">Model.watch()</a></li><li><a href="#model_Model.where">Model.where()</a></li><li><a href="#model_Model.inspect">function Object() { [native code] }.prototype.inspect()</a></li></ul><hr class="separate-api-elements"><h3 id="model_Model"><a href="#model_Model">Model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> values for initial set</li><li class="param">optional
-<span class="method-type">&laquo;[fields]&raquo;</span> object containing the fields that were selected in the query which returned this document. You do <strong>not</strong> need to set this parameter to ensure Mongoose handles your <a href="./api.html#query_Query-select">query projection</a>.</li></ul><div><p>A Model is a class that's your primary tool for interacting with MongoDB. An instance of a Model is called a <a href="./api.html#Document">Document</a>.</p>
-
-<p>In Mongoose, the term "Model" refers to subclasses of the <code>mongoose.Model</code> class. You should not use the <code>mongoose.Model</code> class directly. The <a href="./api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> and <a href="./api.html#connection_Connection-model"><code>connection.model()</code></a> functions create subclasses of <code>mongoose.Model</code> as shown below.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// `UserModel` is a "Model", a subclass of `mongoose.Model`.</span>
-<span class="hljs-keyword">const</span> UserModel = mongoose.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-
-<span class="hljs-comment">// You can use a Model to create new documents using `new`:</span>
-<span class="hljs-keyword">const</span> userDoc = <span class="hljs-keyword">new</span> UserModel({ name: <span class="hljs-string">'Foo'</span> });
-<span class="hljs-keyword">await</span> userDoc.save();
-
-<span class="hljs-comment">// You also use a model to create queries:</span>
-<span class="hljs-keyword">const</span> userFromDb = <span class="hljs-keyword">await</span> UserModel.findOne({ name: <span class="hljs-string">'Foo'</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.aggregate"><a href="#model_Model.aggregate">Model.aggregate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[pipeline]
-<span class="method-type">&laquo;Array&raquo;</span> aggregation pipeline as an array of objects</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Performs <a href="http://docs.mongodb.org/manual/applications/aggregation/">aggregations</a> on the models collection.</p>
-
-<p>If a <code>callback</code> is passed, the <code>aggregate</code> is executed and a <code>Promise</code> is returned. If a callback is not passed, the <code>aggregate</code> itself is returned.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>aggregate()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Find the max balance of all accounts</span>
-Users.aggregate([
-  { $group: { _id: <span class="hljs-literal">null</span>, maxBalance: { $max: <span class="hljs-string">'$balance'</span> }}},
-  { $project: { _id: <span class="hljs-number">0</span>, maxBalance: <span class="hljs-number">1</span> }}
-]).
-then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">res</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(res); <span class="hljs-comment">// [ { maxBalance: 98000 } ]</span>
-});
-
-<span class="hljs-comment">// Or use the aggregation pipeline builder.</span>
-Users.aggregate().
-  group({ _id: <span class="hljs-literal">null</span>, maxBalance: { $max: <span class="hljs-string">'$balance'</span> } }).
-  project(<span class="hljs-string">'-id maxBalance'</span>).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, res</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-    <span class="hljs-built_in">console</span>.log(res); <span class="hljs-comment">// [ { maxBalance: 98 } ]</span>
-  });</code></pre>
-
-<h4>NOTE:</h4>
-
-<ul>
-<li>Arguments are not cast to the model's schema because <code>$project</code> operators allow redefining the "shape" of the documents at any stage of the pipeline, which may leave documents in an incompatible format.</li>
-<li>The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).</li>
-<li>Requires MongoDB >= 2.1</li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.bulkWrite"><a href="#model_Model.bulkWrite">Model.bulkWrite()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ops
-<span class="method-type">&laquo;Array&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[ops.insertOne.document]
-<span class="method-type">&laquo;Object&raquo;</span> The document to insert</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Update the first document that matches this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.update]
-<span class="method-type">&laquo;Object&raquo;</span> An object containing <a href="https://docs.mongodb.com/manual/reference/operator/update/">update operators</a></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, insert a doc if none match</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.collation]
-<span class="method-type">&laquo;Object&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations">MongoDB collation</a> to use</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.arrayFilters]
-<span class="method-type">&laquo;Array&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-array-filters.html">array filters</a> used in <code>update</code></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Update all the documents that match this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.update]
-<span class="method-type">&laquo;Object&raquo;</span> An object containing <a href="https://docs.mongodb.com/manual/reference/operator/update/">update operators</a></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, insert a doc if no documents match <code>filter</code></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.collation]
-<span class="method-type">&laquo;Object&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations">MongoDB collation</a> to use</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.arrayFilters]
-<span class="method-type">&laquo;Array&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-array-filters.html">array filters</a> used in <code>update</code></li></ul><ul style="margin-top: 0.5em"><li>[opts.deleteOne.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Delete the first document that matches this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.deleteMany.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Delete all documents that match this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.replaceOne.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Replace the first document that matches this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.replaceOne.replacement]
-<span class="method-type">&laquo;Object&raquo;</span> The replacement document</li></ul><ul style="margin-top: 0.5em"><li>[opts.replaceOne.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, insert a doc if no documents match <code>filter</code></li></ul><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.ordered=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, execute writes in order and stop at the first error. If false, execute writes in parallel and continue until all writes have either succeeded or errored.</li></ul><ul style="margin-top: 0.5em"><li>[options.session=null]
-<span class="method-type">&laquo;ClientSession&raquo;</span> The session associated with this bulk write. See <a href="/docs/transactions.html">transactions docs</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.w=1]
-<span class="method-type">&laquo;String|number&raquo;</span> The <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a>. See <a href="/docs/api.html#query_Query-w"><code>Query#w()</code></a> for more information.</li></ul><ul style="margin-top: 0.5em"><li>[options.wtimeout=null]
-<span class="method-type">&laquo;number&raquo;</span> The <a href="https://docs.mongodb.com/manual/reference/write-concern/#wtimeout">write concern timeout</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.j=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> If false, disable <a href="https://docs.mongodb.com/manual/reference/write-concern/#j-option">journal acknowledgement</a></li></ul><ul style="margin-top: 0.5em"><li>[options.bypassDocumentValidation=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, disable <a href="https://docs.mongodb.com/manual/core/schema-validation/">MongoDB server-side schema validation</a> for all writes in this bulk.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback <code>function(error, bulkWriteOpResult) {}</code></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> resolves to a <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult"><code>BulkWriteOpResult</code></a> if the operation succeeds</li></ul><div><p>Sends multiple <code>insertOne</code>, <code>updateOne</code>, <code>updateMany</code>, <code>replaceOne</code>, <code>deleteOne</code>, and/or <code>deleteMany</code> operations to the MongoDB server in one command. This is faster than sending multiple independent operations (like) if you use <code>create()</code>) because with <code>bulkWrite()</code> there is only one round trip to MongoDB.</p>
-
-<p>Mongoose will perform casting on all operations you provide.</p>
-
-<p>This function does <strong>not</strong> trigger any middleware, not <code>save()</code> nor <code>update()</code>. If you need to trigger <code>save()</code> middleware for every document use <a href="http://mongoosejs.com/docs/api.html#model_Model.create"><code>create()</code></a> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character.bulkWrite([
-  {
-    insertOne: {
-      <span class="hljs-built_in">document</span>: {
-        name: <span class="hljs-string">'Eddard Stark'</span>,
-        title: <span class="hljs-string">'Warden of the North'</span>
-      }
-    }
-  },
-  {
-    updateOne: {
-      filter: { name: <span class="hljs-string">'Eddard Stark'</span> },
-      <span class="hljs-comment">// If you were using the MongoDB driver directly, you'd need to do</span>
-      <span class="hljs-comment">// `update: { $set: { title: ... } }` but mongoose adds $set for</span>
-      <span class="hljs-comment">// you.</span>
-      update: { title: <span class="hljs-string">'Hand of the King'</span> }
-    }
-  },
-  {
-    deleteOne: {
-      {
-        filter: { name: <span class="hljs-string">'Eddard Stark'</span> }
-      }
-    }
-  }
-]).then(res =&gt; {
- <span class="hljs-comment">// Prints "1 1 1"</span>
- <span class="hljs-built_in">console</span>.log(res.insertedCount, res.modifiedCount, res.deletedCount);
-});</code></pre>
-
-<p>The <a href="https://docs.mongodb.com/manual/reference/method/db.collection.bulkWrite/#db.collection.bulkWrite">supported operations</a> are:</p>
-
-<ul>
-<li><code>insertOne</code></li>
-<li><code>updateOne</code></li>
-<li><code>updateMany</code></li>
-<li><code>deleteOne</code></li>
-<li><code>deleteMany</code></li>
-<li><code>replaceOne</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.count"><a href="#model_Model.count">Model.count()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Counts number of documents that match <code>filter</code> in a database collection.</p>
-
-<p>This method is deprecated. If you want to count the number of documents in a collection, e.g. <code>count({})</code>, use the <a href="/docs/api.html#model_Model.estimatedDocumentCount"><code>estimatedDocumentCount()</code> function</a> instead. Otherwise, use the <a href="/docs/api.html#model_Model.countDocuments"><code>countDocuments()</code></a> function instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Adventure.count({ type: <span class="hljs-string">'jungle'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d jungle adventures'</span>, count);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.countDocuments"><a href="#model_Model.countDocuments">Model.countDocuments()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Counts number of documents matching <code>filter</code> in a database collection.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Adventure.countDocuments({ type: <span class="hljs-string">'jungle'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d jungle adventures'</span>, count);
-});</code></pre>
-
-<p>If you want to count all documents in a large collection, use the <a href="/docs/api.html#model_Model.estimatedDocumentCount"><code>estimatedDocumentCount()</code> function</a> instead. If you call <code>countDocuments({})</code>, MongoDB will always execute a full collection scan and <strong>not</strong> use any indexes.</p>
-
-<p>The <code>countDocuments()</code> function is similar to <code>count()</code>, but there are a <a href="https://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments">few operators that <code>countDocuments()</code> does not support</a>. Below are the operators that <code>count()</code> supports but <code>countDocuments()</code> does not, and the suggested replacement:</p>
-
-<ul>
-<li><code>$where</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/expr/"><code>$expr</code></a></li>
-<li><code>$near</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/center/#op._S_center"><code>$center</code></a></li>
-<li><code>$nearSphere</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/centerSphere/#op._S_centerSphere"><code>$centerSphere</code></a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.create"><a href="#model_Model.create">Model.create()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">docs
-<span class="method-type">&laquo;Array|Object&raquo;</span> Documents to insert, as a spread or array</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Options passed down to <code>save()</code>. To specify <code>options</code>, <code>docs</code> <strong>must</strong> be an array, not a spread.</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Shortcut for saving one or more documents to the database. <code>MyModel.create(docs)</code> does <code>new MyModel(doc).save()</code> for every doc in docs.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>save()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// pass a spread of docs and a callback</span>
-Candy.create({ type: <span class="hljs-string">'jelly bean'</span> }, { type: <span class="hljs-string">'snickers'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, jellybean, snickers</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-comment">// ...</span>
-});
-
-<span class="hljs-comment">// pass an array of docs</span>
-<span class="hljs-keyword">var</span> array = [{ type: <span class="hljs-string">'jelly bean'</span> }, { type: <span class="hljs-string">'snickers'</span> }];
-Candy.create(array, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, candies</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-comment">// ...</span>
-
-  <span class="hljs-keyword">var</span> jellybean = candies[<span class="hljs-number">0</span>];
-  <span class="hljs-keyword">var</span> snickers = candies[<span class="hljs-number">1</span>];
-  <span class="hljs-comment">// ...</span>
-});
-
-<span class="hljs-comment">// callback is optional; use the returned promise if you like:</span>
-<span class="hljs-keyword">var</span> promise = Candy.create({ type: <span class="hljs-string">'jawbreaker'</span> });
-promise.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">jawbreaker</span>) </span>{
-  <span class="hljs-comment">// ...</span>
-})</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.createCollection"><a href="#model_Model.createCollection">Model.createCollection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Db.html#createCollection">MongoDB driver docs</a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Create the collection for this model. By default, if no indexes are specified, mongoose will not create the collection for the model until any documents are created. Use this method to create the collection explicitly.</p>
-
-<p>Note 1: You may need to call this before starting a transaction See <a href='https://docs.mongodb.com/manual/core/transactions/#transactions-and-operations'>https://docs.mongodb.com/manual/core/transactions/#transactions-and-operations</a></p>
-
-<p>Note 2: You don't have to call this if your schema contains index or unique field. In that case, just use <code>Model.init()</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> userSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> })
-<span class="hljs-keyword">var</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-User.createCollection().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">collection</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Collection is created!'</span>);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.createIndexes"><a href="#model_Model.createIndexes">Model.createIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> internal options</li><li class="param">[cb]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Similar to <code>ensureIndexes()</code>, except for it uses the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex"><code>createIndex</code></a> function.</p></div><hr class="separate-api-elements"><h3 id="model_Model.deleteMany"><a href="#model_Model.deleteMany">Model.deleteMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Deletes all of the documents that match <code>conditions</code> from the collection. Behaves like <code>remove()</code>, but deletes all documents that match <code>conditions</code> regardless of the <code>single</code> option.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{});</code></pre>
-
-<h4>Note:</h4>
-
-<p>Like <code>Model.remove()</code>, this function does <strong>not</strong> trigger <code>pre('remove')</code> or <code>post('remove')</code> hooks.</p></div><hr class="separate-api-elements"><h3 id="model_Model.deleteOne"><a href="#model_Model.deleteOne">Model.deleteOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Deletes the first document that matches <code>conditions</code> from the collection. Behaves like <code>remove()</code>, but deletes at most one document regardless of the <code>single</code> option.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{});</code></pre>
-
-<h4>Note:</h4>
-
-<p>Like <code>Model.remove()</code>, this function does <strong>not</strong> trigger <code>pre('remove')</code> or <code>post('remove')</code> hooks.</p></div><hr class="separate-api-elements"><h3 id="model_Model.discriminator"><a href="#model_Model.discriminator">Model.discriminator()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> discriminator model name</li><li class="param">schema
-<span class="method-type">&laquo;Schema&raquo;</span> discriminator model schema</li><li class="param">value
-<span class="method-type">&laquo;String&raquo;</span> the string stored in the <code>discriminatorKey</code> property</li></ul><div><p>Adds a discriminator type.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">BaseSchema</span>(<span class="hljs-params"></span>) </span>{
-  Schema.apply(<span class="hljs-keyword">this</span>, <span class="hljs-built_in">arguments</span>);
-
-  <span class="hljs-keyword">this</span>.add({
-    name: <span class="hljs-built_in">String</span>,
-    createdAt: <span class="hljs-built_in">Date</span>
-  });
-}
-util.inherits(BaseSchema, Schema);
-
-<span class="hljs-keyword">var</span> PersonSchema = <span class="hljs-keyword">new</span> BaseSchema();
-<span class="hljs-keyword">var</span> BossSchema = <span class="hljs-keyword">new</span> BaseSchema({ department: <span class="hljs-built_in">String</span> });
-
-<span class="hljs-keyword">var</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, PersonSchema);
-<span class="hljs-keyword">var</span> Boss = Person.discriminator(<span class="hljs-string">'Boss'</span>, BossSchema);
-<span class="hljs-keyword">new</span> Boss().__t; <span class="hljs-comment">// "Boss". `__t` is the default `discriminatorKey`</span>
-
-<span class="hljs-keyword">var</span> employeeSchema = <span class="hljs-keyword">new</span> Schema({ boss: ObjectId });
-<span class="hljs-keyword">var</span> Employee = Person.discriminator(<span class="hljs-string">'Employee'</span>, employeeSchema, <span class="hljs-string">'staff'</span>);
-<span class="hljs-keyword">new</span> Employee().__t; <span class="hljs-comment">// "staff" because of 3rd argument above</span></code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.distinct"><a href="#model_Model.distinct">Model.distinct()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">field
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> optional</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Creates a Query for a <code>distinct</code> operation.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<h4>Example</h4>
-
-<pre><code>Link.distinct(<span class="hljs-string">'url'</span>, { clicks: {$gt: <span class="hljs-number">100</span>}}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, result</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-
-  assert(<span class="hljs-built_in">Array</span>.isArray(result));
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'unique urls with more than 100 clicks'</span>, result);
-})
-
-<span class="hljs-keyword">var</span> query = Link.distinct(<span class="hljs-string">'url'</span>);
-query.exec(callback);</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.ensureIndexes"><a href="#model_Model.ensureIndexes">Model.ensureIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> internal options</li><li class="param">[cb]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Sends <code>createIndex</code> commands to mongo for each index declared in the schema. The <code>createIndex</code> commands are sent in series.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Event.ensureIndexes(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-});</code></pre>
-
-<p>After completion, an <code>index</code> event is emitted on this <code>Model</code> passing an error if one occurred.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> Schema({ thing: { type: <span class="hljs-string">'string'</span>, unique: <span class="hljs-literal">true</span> }})
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'Event'</span>, eventSchema);
-
-Event.on(<span class="hljs-string">'index'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-built_in">console</span>.error(err); <span class="hljs-comment">// error occurred during index creation</span>
-})</code></pre>
-
-<p><em>NOTE: It is not recommended that you run this in production. Index creation may impact database performance depending on your load. Use with caution.</em></p></div><hr class="separate-api-elements"><h3 id="model_Model.estimatedDocumentCount"><a href="#model_Model.estimatedDocumentCount">Model.estimatedDocumentCount()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Estimates the number of documents in the MongoDB collection. Faster than using <code>countDocuments()</code> for large collections because <code>estimatedDocumentCount()</code> uses collection metadata rather than scanning the entire collection.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> numAdventures = Adventure.estimatedDocumentCount();</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-events"><a href="#model_Model-events">Model.events</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Event emitter that reports any errors that occurred. Useful for global error handling.</p>
-
-<h4>Example:</h4>
-
-<pre><code>MyModel.events.on(<span class="hljs-string">'error'</span>, err =&gt; <span class="hljs-built_in">console</span>.log(err.message));
-
-<span class="hljs-comment">// Prints a 'CastError' because of the above handler</span>
-<span class="hljs-keyword">await</span> MyModel.findOne({ _id: <span class="hljs-string">'notanid'</span> }).catch(noop);</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.exists"><a href="#model_Model.exists">Model.exists()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Returns true if at least one document exists in the database that matches the given <code>filter</code>, and false otherwise.</p>
-
-<p>Under the hood, <code>MyModel.exists({ answer: 42 })</code> is equivalent to <code>MyModel.findOne({ answer: 42 }).select({ _id: 1 }).lean().then(doc => !!doc)</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> Character.deleteMany({});
-<span class="hljs-keyword">await</span> Character.create({ name: <span class="hljs-string">'Jean-Luc Picard'</span> });
-
-<span class="hljs-keyword">await</span> Character.exists({ name: <span class="hljs-regexp">/picard/i</span> }); <span class="hljs-comment">// true</span>
-<span class="hljs-keyword">await</span> Character.exists({ name: <span class="hljs-regexp">/riker/i</span> }); <span class="hljs-comment">// false</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOne()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.find"><a href="#model_Model.find">Model.find()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[projection]
-<span class="method-type">&laquo;Object|String&raquo;</span> optional fields to return, see <a href="#query_Query-select"><code>Query.prototype.select()</code></a></li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Finds documents</p>
-
-<p>The <code>conditions</code> are cast to their respective SchemaTypes before the command is sent.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// named john and at least 18</span>
-MyModel.find({ name: <span class="hljs-string">'john'</span>, age: { $gte: <span class="hljs-number">18</span> }});
-
-<span class="hljs-comment">// executes, passing results to callback</span>
-MyModel.find({ name: <span class="hljs-string">'john'</span>, age: { $gte: <span class="hljs-number">18</span> }}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});
-
-<span class="hljs-comment">// executes, name LIKE john and only selecting the "name" and "friends" fields</span>
-MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-string">'name friends'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{ })
-
-<span class="hljs-comment">// passing options</span>
-MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> })
-
-<span class="hljs-comment">// passing options and executes</span>
-MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});
-
-<span class="hljs-comment">// executing a query explicitly</span>
-<span class="hljs-keyword">var</span> query = MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> })
-query.exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});
-
-<span class="hljs-comment">// using the promise returned from executing a query</span>
-<span class="hljs-keyword">var</span> query = MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> });
-<span class="hljs-keyword">var</span> promise = query.exec();
-promise.addBack(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findById"><a href="#model_Model.findById">Model.findById()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|String|Number&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[projection]
-<span class="method-type">&laquo;Object|String&raquo;</span> optional fields to return, see <a href="#query_Query-select"><code>Query.prototype.select()</code></a></li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Finds a single document by its _id field. <code>findById(id)</code> is almost* equivalent to <code>findOne({ _id: id })</code>. If you want to query by a document's <code>_id</code>, use <code>findById()</code> instead of <code>findOne()</code>.</p>
-
-<p>The <code>id</code> is cast based on the Schema before sending the command.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOne()</code></li>
-</ul>
-
-<p>* Except for how it treats <code>undefined</code>. If you use <code>findOne()</code>, you'll see that <code>findOne(undefined)</code> and <code>findOne({ _id: undefined })</code> are equivalent to <code>findOne({})</code> and return arbitrary documents. However, mongoose translates <code>findById(undefined)</code> into <code>findOne({ _id: null })</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// find adventure by id and execute</span>
-Adventure.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findById(id).exec(callback);
-
-<span class="hljs-comment">// select only the adventures name and length</span>
-Adventure.findById(id, <span class="hljs-string">'name length'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findById(id, <span class="hljs-string">'name length'</span>).exec(callback);
-
-<span class="hljs-comment">// include all properties except for `length`</span>
-Adventure.findById(id, <span class="hljs-string">'-length'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// passing options (in this case return the raw js objects, not mongoose documents by passing `lean`</span>
-Adventure.findById(id, <span class="hljs-string">'name'</span>, { lean: <span class="hljs-literal">true</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findById(id, <span class="hljs-string">'name'</span>).lean().exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findByIdAndDelete"><a href="#model_Model.findByIdAndDelete">Model.findByIdAndDelete()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|Number|String&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a MongoDB <code>findOneAndDelete()</code> command by a document's _id field. In other words, <code>findByIdAndDelete(id)</code> is a shorthand for <code>findOneAndDelete({ _id: id })</code>.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndDelete()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.findByIdAndRemove"><a href="#model_Model.findByIdAndRemove">Model.findByIdAndRemove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|Number|String&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a mongodb findAndModify remove command by a document's _id field. <code>findByIdAndRemove(id, ...)</code> is equivalent to <code>findOneAndRemove({ _id: id }, ...)</code>.</p>
-
-<p>Finds a matching document, removes it, passing the found document (if any) to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndRemove()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findByIdAndRemove(id, options, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndRemove(id, options)  <span class="hljs-comment">// return Query</span>
-A.findByIdAndRemove(id, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndRemove(id) <span class="hljs-comment">// returns Query</span>
-A.findByIdAndRemove()           <span class="hljs-comment">// returns Query</span></code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findByIdAndUpdate"><a href="#model_Model.findByIdAndUpdate">Model.findByIdAndUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|Number|String&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[update]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="/docs/api.html#query_Query-lean"><code>Query.lean()</code></a> and the <a href="/docs/tutorials/lean.html">Mongoose lean tutorial</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issues a mongodb findAndModify update command by a document's _id field. <code>findByIdAndUpdate(id, ...)</code> is equivalent to <code>findOneAndUpdate({ _id: id }, ...)</code>.</p>
-
-<p>Finds a matching document, updates it according to the <code>update</code> arg, passing any <code>options</code>, and returns the found document (if any) to the callback. The query executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndUpdate()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>new</code>: bool - true to return the modified document rather than the original. defaults to false</li>
-<li><code>upsert</code>: bool - creates the object if it doesn't exist. defaults to false.</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findByIdAndUpdate(id, update, options, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndUpdate(id, update, options)  <span class="hljs-comment">// returns Query</span>
-A.findByIdAndUpdate(id, update, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndUpdate(id, update)           <span class="hljs-comment">// returns Query</span>
-A.findByIdAndUpdate()                     <span class="hljs-comment">// returns Query</span></code></pre>
-
-<h4>Note:</h4>
-
-<p>All top level update keys which are not <code>atomic</code> operation names are treated as set operations:</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findByIdAndUpdate(id, { name: <span class="hljs-string">'jason bourne'</span> }, options, callback)
-
-<span class="hljs-comment">// is sent as</span>
-Model.findByIdAndUpdate(id, { $set: { name: <span class="hljs-string">'jason bourne'</span> }}, options, callback)</code></pre>
-
-<p>This helps prevent accidentally overwriting your document with <code>{ name: 'jason bourne' }</code>.</p>
-
-<h4>Note:</h4>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findOne"><a href="#model_Model.findOne">Model.findOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[projection]
-<span class="method-type">&laquo;Object|String&raquo;</span> optional fields to return, see <a href="#query_Query-select"><code>Query.prototype.select()</code></a></li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Finds one document.</p>
-
-<p>The <code>conditions</code> are cast to their respective SchemaTypes before the command is sent.</p>
-
-<p><em>Note:</em> <code>conditions</code> is optional, and if <code>conditions</code> is null or undefined, mongoose will send an empty <code>findOne</code> command to MongoDB, which will return an arbitrary document. If you're querying by <code>_id</code>, use <code>findById()</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// find one iphone adventures - iphone adventures??</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// select only the adventures name</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// specify options, in this case lean</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>, { lean: <span class="hljs-literal">true</span> }, callback);
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>, { lean: <span class="hljs-literal">true</span> }).exec(callback);
-
-<span class="hljs-comment">// chaining findOne queries (same as above)</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }).select(<span class="hljs-string">'name'</span>).lean().exec(callback);</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndDelete"><a href="#model_Model.findOneAndDelete">Model.findOneAndDelete()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a MongoDB <code>findOneAndDelete()</code> command.</p>
-
-<p>Finds a matching document, removes it, and passes the found document (if any) to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndDelete()</code></li>
-</ul>
-
-<p>This function differs slightly from <code>Model.findOneAndRemove()</code> in that <code>findOneAndRemove()</code> becomes a <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/">MongoDB <code>findAndModify()</code> command</a>, as opposed to a <code>findOneAndDelete()</code> command. For most mongoose use cases, this distinction is purely pedantic. You should use <code>findOneAndDelete()</code> unless you have a good reason not to.</p>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>projection</code>: like select, it determines which fields to return, ex. <code>{ projection: { _id: 0 } }</code></li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndDelete(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndDelete(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.findOneAndDelete(conditions, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndDelete(conditions) <span class="hljs-comment">// returns Query</span>
-A.findOneAndDelete()           <span class="hljs-comment">// returns Query</span></code></pre>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndRemove"><a href="#model_Model.findOneAndRemove">Model.findOneAndRemove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a mongodb findAndModify remove command.</p>
-
-<p>Finds a matching document, removes it, passing the found document (if any) to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndRemove()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>projection</code>: like select, it determines which fields to return, ex. <code>{ projection: { _id: 0 } }</code></li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndRemove(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndRemove(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.findOneAndRemove(conditions, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndRemove(conditions) <span class="hljs-comment">// returns Query</span>
-A.findOneAndRemove()           <span class="hljs-comment">// returns Query</span></code></pre>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndReplace"><a href="#model_Model.findOneAndReplace">Model.findOneAndReplace()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> Replace the first document that matches this filter</li><li class="param">[replacement]
-<span class="method-type">&laquo;Object&raquo;</span> Replace with this document</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="http://mongoosejs.com/docs/api.html#query_Query-lean"><code>Query.lean()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a MongoDB <code>findOneAndReplace()</code> command.</p>
-
-<p>Finds a matching document, replaces it with the provided doc, and passes the returned doc to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following query middleware.</p>
-
-<ul>
-<li><code>findOneAndReplace()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>projection</code>: like select, it determines which fields to return, ex. <code>{ projection: { _id: 0 } }</code></li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndReplace(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndReplace(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.findOneAndReplace(conditions, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndReplace(conditions) <span class="hljs-comment">// returns Query</span>
-A.findOneAndReplace()           <span class="hljs-comment">// returns Query</span></code></pre>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndUpdate"><a href="#model_Model.findOneAndUpdate">Model.findOneAndUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[update]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="/docs/api.html#query_Query-lean"><code>Query.lean()</code></a> and <a href="/docs/tutorials/lean.html">the Mongoose lean tutorial</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issues a mongodb findAndModify update command.</p>
-
-<p>Finds a matching document, updates it according to the <code>update</code> arg, passing any <code>options</code>, and returns the found document (if any) to the callback. The query executes if <code>callback</code> is passed else a Query object is returned.</p>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>new</code>: bool - if true, return the modified document rather than the original. defaults to false (changed in 4.0)</li>
-<li><code>upsert</code>: bool - creates the object if it doesn't exist. defaults to false.</li>
-<li><code>fields</code>: {Object|String} - Field selection. Equivalent to <code>.select(fields).findOneAndUpdate()</code></li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndUpdate(conditions, update, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndUpdate(conditions, update, options)  <span class="hljs-comment">// returns Query</span>
-A.findOneAndUpdate(conditions, update, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndUpdate(conditions, update)           <span class="hljs-comment">// returns Query</span>
-A.findOneAndUpdate()                             <span class="hljs-comment">// returns Query</span></code></pre>
-
-<h4>Note:</h4>
-
-<p>All top level update keys which are not <code>atomic</code> operation names are treated as set operations:</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = { name: <span class="hljs-string">'borne'</span> };
-Model.findOneAndUpdate(query, { name: <span class="hljs-string">'jason bourne'</span> }, options, callback)
-
-<span class="hljs-comment">// is sent as</span>
-Model.findOneAndUpdate(query, { $set: { name: <span class="hljs-string">'jason bourne'</span> }}, options, callback)</code></pre>
-
-<p>This helps prevent accidentally overwriting your document with <code>{ name: 'jason bourne' }</code>.</p>
-
-<h4>Note:</h4>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.geoSearch"><a href="#model_Model.geoSearch">Model.geoSearch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> an object that specifies the match condition (required)</li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> for the geoSearch, some (near, maxDistance) are required</li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object|Boolean&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="/docs/api.html#query_Query-lean"><code>Query.lean()</code></a> and the <a href="/docs/tutorials/lean.html">Mongoose lean tutorial</a>.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Implements <code>$geoSearch</code> functionality for Mongoose</p>
-
-<p>This function does not trigger any middleware</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> options = { near: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> };
-Locations.geoSearch({ type : <span class="hljs-string">"house"</span> }, options, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, res</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(res);
-});</code></pre>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>near</code> {Array} x,y point to search for</li>
-<li><code>maxDistance</code> {Number} the maximum distance from the point near that a result can be</li>
-<li><code>limit</code> {Number} The maximum number of results to return</li>
-<li><code>lean</code> {Object|Boolean} return the raw object instead of the Mongoose Model</li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.hydrate"><a href="#model_Model.hydrate">Model.hydrate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Model&raquo;</span> document instance</li></ul><div><p>Shortcut for creating a new Document from existing raw data, pre-saved in the DB. The document returned has no paths marked as modified initially.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// hydrate previous data into a Mongoose document</span>
-<span class="hljs-keyword">var</span> mongooseCandy = Candy.hydrate({ _id: <span class="hljs-string">'54108337212ffb6d459f854c'</span>, type: <span class="hljs-string">'jelly bean'</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.init"><a href="#model_Model.init">Model.init()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>This function is responsible for building <a href="https://docs.mongodb.com/manual/indexes/">indexes</a>, unless <a href="http://mongoosejs.com/docs/guide.html#autoIndex"><code>autoIndex</code></a> is turned off.</p>
-
-<p>Mongoose calls this function automatically when a model is created using <a href="/docs/api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> or * <a href="/docs/api.html#connection_Connection-model"><code>connection.model()</code></a>, so you don't need to call it. This function is also idempotent, so you may call it to get back a promise that will resolve when your indexes are finished building as an alternative to <a href="/docs/guide.html#indexes"><code>MyModel.on('index')</code></a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> Schema({ thing: { type: <span class="hljs-string">'string'</span>, unique: <span class="hljs-literal">true</span> }})
-<span class="hljs-comment">// This calls `Event.init()` implicitly, so you don't need to call</span>
-<span class="hljs-comment">// `Event.init()` on your own.</span>
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'Event'</span>, eventSchema);
-
-Event.init().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">Event</span>) </span>{
-  <span class="hljs-comment">// You can also use `Event.on('index')` if you prefer event emitters</span>
-  <span class="hljs-comment">// over promises.</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Indexes are done building!'</span>);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.insertMany"><a href="#model_Model.insertMany">Model.insertMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc(s)
-<span class="method-type">&laquo;Array|Object|*&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#insertMany">mongodb driver options</a></li><li class="param">[options.ordered
-<span class="method-type">&laquo;Boolean&raquo;</span> = true] if true, will fail fast on the first error encountered. If false, will insert all the documents it can and report errors later. An <code>insertMany()</code> with <code>ordered = false</code> is called an &quot;unordered&quot; <code>insertMany()</code>.</li><li class="param">[options.rawResult
-<span class="method-type">&laquo;Boolean&raquo;</span> = false] if false, the returned promise resolves to the documents that passed mongoose document validation. If <code>true</code>, will return the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~insertWriteOpCallback">raw result from the MongoDB driver</a> with a <code>mongoose</code> property that contains <code>validationErrors</code> if this is an unordered <code>insertMany</code>.</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Shortcut for validating an array of documents and inserting them into MongoDB if they're all valid. This function is faster than <code>.create()</code> because it only sends one operation to the server, rather than one for each document.</p>
-
-<p>Mongoose always validates each document <strong>before</strong> sending <code>insertMany</code> to MongoDB. So if one document has a validation error, no documents will be saved, unless you set <a href="https://docs.mongodb.com/manual/reference/method/db.collection.insertMany/#error-handling">the <code>ordered</code> option to false</a>.</p>
-
-<p>This function does <strong>not</strong> trigger save middleware.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>insertMany()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> arr = [{ name: <span class="hljs-string">'Star Wars'</span> }, { name: <span class="hljs-string">'The Empire Strikes Back'</span> }];
-Movies.insertMany(arr, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, docs</span>) </span>{});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.listIndexes"><a href="#model_Model.listIndexes">Model.listIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[cb]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns <code>undefined</code> if callback is specified, returns a promise if no callback.</li></ul><div><p>Lists the indexes currently defined in MongoDB. This may or may not be the same as the indexes defined in your schema depending on whether you use the <a href="/docs/guide.html#autoIndex"><code>autoIndex</code> option</a> and if you build indexes manually.</p></div><hr class="separate-api-elements"><h3 id="model_Model.mapReduce"><a href="#model_Model.mapReduce">Model.mapReduce()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">o
-<span class="method-type">&laquo;Object&raquo;</span> an object specifying map-reduce options</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes a mapReduce command.</p>
-
-<p><code>o</code> is an object specifying all mapReduce options as well as the map and reduce functions. All options are delegated to the driver implementation. See <a href="http://mongodb.github.io/node-mongodb-native/api-generated/collection.html#mapreduce">node-mongodb-native mapReduce() documentation</a> for more detail about options.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> o = {};
-<span class="hljs-comment">// `map()` and `reduce()` are run on the MongoDB server, not Node.js,</span>
-<span class="hljs-comment">// these functions are converted to strings</span>
-o.map = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{ emit(<span class="hljs-keyword">this</span>.name, <span class="hljs-number">1</span>) };
-o.reduce = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">k, vals</span>) </span>{ <span class="hljs-keyword">return</span> vals.length };
-User.mapReduce(o, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, results</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(results)
-})</code></pre>
-
-<h4>Other options:</h4>
-
-<ul>
-<li><code>query</code> {Object} query filter object.</li>
-<li><code>sort</code> {Object} sort input objects using this key</li>
-<li><code>limit</code> {Number} max number of documents</li>
-<li><code>keeptemp</code> {Boolean, default:false} keep temporary data</li>
-<li><code>finalize</code> {Function} finalize function</li>
-<li><code>scope</code> {Object} scope variables exposed to map/reduce/finalize during execution</li>
-<li><code>jsMode</code> {Boolean, default:false} it is possible to make the execution stay in JS. Provided in MongoDB > 2.0.X</li>
-<li><code>verbose</code> {Boolean, default:false} provide statistics on job execution time.</li>
-<li><code>readPreference</code> {String}</li>
-<li><code>out*</code> {Object, default: {inline:1}} sets the output target for the map reduce job.</li>
-</ul>
-
-<h4>* out options:</h4>
-
-<ul>
-<li><code>{inline:1}</code> the results are returned in an array</li>
-<li><code>{replace: 'collectionName'}</code> add the results to collectionName: the results replace the collection</li>
-<li><code>{reduce: 'collectionName'}</code> add the results to collectionName: if dups are detected, uses the reducer / finalize functions</li>
-<li><code>{merge: 'collectionName'}</code> add the results to collectionName: if dups exist the new docs overwrite the old</li>
-</ul>
-
-<p>If <code>options.out</code> is set to <code>replace</code>, <code>merge</code>, or <code>reduce</code>, a Model instance is returned that can be used for further querying. Queries run against this model are all executed with the <a href="/docs/tutorials/lean.html"><code>lean</code> option</a>; meaning only the js object is returned and no Mongoose magic is applied (getters, setters, etc).</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> o = {};
-<span class="hljs-comment">// You can also define `map()` and `reduce()` as strings if your</span>
-<span class="hljs-comment">// linter complains about `emit()` not being defined</span>
-o.map = <span class="hljs-string">'function () { emit(this.name, 1) }'</span>;
-o.reduce = <span class="hljs-string">'function (k, vals) { return vals.length }'</span>;
-o.out = { replace: <span class="hljs-string">'createdCollectionNameForResults'</span> }
-o.verbose = <span class="hljs-literal">true</span>;
-
-User.mapReduce(o, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, model, stats</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'map reduce took %d ms'</span>, stats.processtime)
-  model.find().where(<span class="hljs-string">'value'</span>).gt(<span class="hljs-number">10</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(docs);
-  });
-})
-
-<span class="hljs-comment">// `mapReduce()` returns a promise. However, ES6 promises can only</span>
-<span class="hljs-comment">// resolve to exactly one value,</span>
-o.resolveToObject = <span class="hljs-literal">true</span>;
-<span class="hljs-keyword">var</span> promise = User.mapReduce(o);
-promise.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">res</span>) </span>{
-  <span class="hljs-keyword">var</span> model = res.model;
-  <span class="hljs-keyword">var</span> stats = res.stats;
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'map reduce took %d ms'</span>, stats.processtime)
-  <span class="hljs-keyword">return</span> model.find().where(<span class="hljs-string">'value'</span>).gt(<span class="hljs-number">10</span>).exec();
-}).then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">docs</span>) </span>{
-   <span class="hljs-built_in">console</span>.log(docs);
-}).then(<span class="hljs-literal">null</span>, handleError).end()</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.populate"><a href="#model_Model.populate">Model.populate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">docs
-<span class="method-type">&laquo;Document|Array&raquo;</span> Either a single document or array of documents to populate.</li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> A hash of key/val (path, options) used for population.</li><ul style="margin-top: 0.5em"><li>[options.retainNullValues=false]
-<span class="method-type">&laquo;boolean&raquo;</span> by default, Mongoose removes null and undefined values from populated arrays. Use this option to make <code>populate()</code> retain <code>null</code> and <code>undefined</code> array entries.</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if true, Mongoose will call any getters defined on the <code>localField</code>. By default, Mongoose gets the raw value of <code>localField</code>. For example, you would need to set this option to <code>true</code> if you wanted to <a href="/docs/schematypes.html#schematype-options">add a <code>lowercase</code> getter to your <code>localField</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.clone=false]
-<span class="method-type">&laquo;boolean&raquo;</span> When you do <code>BlogPost.find().populate(&#39;author&#39;)</code>, blog posts with the same author will share 1 copy of an <code>author</code> doc. Enable this option to make Mongoose clone populated docs before assigning them.</li></ul><ul style="margin-top: 0.5em"><li>[options.match=null]
-<span class="method-type">&laquo;Object|Function&raquo;</span> Add an additional filter to the populate query. Can be a filter object containing <a href="https://docs.mongodb.com/manual/tutorial/query-documents/">MongoDB query syntax</a>, or a function that returns a filter object.</li></ul><ul style="margin-top: 0.5em"><li>[options.skipInvalidIds=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> By default, Mongoose throws a cast error if <code>localField</code> and <code>foreignField</code> schemas don&#39;t line up. If you enable this option, Mongoose will instead filter out any <code>localField</code> properties that cannot be casted to <code>foreignField</code>&#39;s schema type.</li></ul><li class="param">[callback(err,doc)]
-<span class="method-type">&laquo;Function&raquo;</span> Optional callback, executed upon completion. Receives <code>err</code> and the <code>doc(s)</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Populates document references.</p>
-
-<h4>Available top-level options:</h4>
-
-<ul>
-<li>path: space delimited path(s) to populate</li>
-<li>select: optional fields to select</li>
-<li>match: optional query conditions to match</li>
-<li>model: optional name of the model to use for population</li>
-<li>options: optional query options like sort, limit, etc</li>
-<li>justOne: optional boolean, if true Mongoose will always set <code>path</code> to an array. Inferred from schema by default.</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// populates a single object</span>
-User.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-  <span class="hljs-keyword">var</span> opts = [
-    { path: <span class="hljs-string">'company'</span>, match: { x: <span class="hljs-number">1</span> }, select: <span class="hljs-string">'name'</span> },
-    { path: <span class="hljs-string">'notes'</span>, options: { limit: <span class="hljs-number">10</span> }, model: <span class="hljs-string">'override'</span> }
-  ];
-
-  User.populate(user, opts, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(user);
-  });
-});
-
-<span class="hljs-comment">// populates an array of objects</span>
-User.find(match, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, users</span>) </span>{
-  <span class="hljs-keyword">var</span> opts = [{ path: <span class="hljs-string">'company'</span>, match: { x: <span class="hljs-number">1</span> }, select: <span class="hljs-string">'name'</span> }];
-
-  <span class="hljs-keyword">var</span> promise = User.populate(users, opts);
-  promise.then(<span class="hljs-built_in">console</span>.log).end();
-})
-
-<span class="hljs-comment">// imagine a Weapon model exists with two saved documents:</span>
-<span class="hljs-comment">//   { _id: 389, name: 'whip' }</span>
-<span class="hljs-comment">//   { _id: 8921, name: 'boomerang' }</span>
-<span class="hljs-comment">// and this schema:</span>
-<span class="hljs-comment">// new Schema({</span>
-<span class="hljs-comment">//   name: String,</span>
-<span class="hljs-comment">//   weapon: { type: ObjectId, ref: 'Weapon' }</span>
-<span class="hljs-comment">// });</span>
-
-<span class="hljs-keyword">var</span> user = { name: <span class="hljs-string">'Indiana Jones'</span>, weapon: <span class="hljs-number">389</span> };
-Weapon.populate(user, { path: <span class="hljs-string">'weapon'</span>, model: <span class="hljs-string">'Weapon'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(user.weapon.name); <span class="hljs-comment">// whip</span>
-})
-
-<span class="hljs-comment">// populate many plain objects</span>
-<span class="hljs-keyword">var</span> users = [{ name: <span class="hljs-string">'Indiana Jones'</span>, weapon: <span class="hljs-number">389</span> }]
-users.push({ name: <span class="hljs-string">'Batman'</span>, weapon: <span class="hljs-number">8921</span> })
-Weapon.populate(users, { path: <span class="hljs-string">'weapon'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, users</span>) </span>{
-  users.forEach(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">user</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s uses a %s'</span>, users.name, user.weapon.name)
-    <span class="hljs-comment">// Indiana Jones uses a whip</span>
-    <span class="hljs-comment">// Batman uses a boomerang</span>
-  });
-});
-<span class="hljs-comment">// Note that we didn't need to specify the Weapon model because</span>
-<span class="hljs-comment">// it is in the schema's ref</span></code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-$where"><a href="#model_Model-$where">Model.prototype.$where</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Additional properties to attach to the query when calling <code>save()</code> and <code>isNew</code> is false.</p></div><hr class="separate-api-elements"><h3 id="model_Model-$where"><a href="#model_Model-$where">Model.prototype.$where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">argument
-<span class="method-type">&laquo;String|Function&raquo;</span> is a javascript string or anonymous function</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Creates a <code>Query</code> and specifies a <code>$where</code> condition.</p>
-
-<p>Sometimes you need to query for things in mongodb using a JavaScript expression. You can do so via <code>find({ $where: javascript })</code>, or you can use the mongoose shortcut method $where via a Query chain or from your mongoose Model.</p>
-
-<pre><code>Blog.$where(<span class="hljs-string">'this.username.indexOf("val") !== -1'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-base"><a href="#model_Model-base">Model.prototype.base</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Base Mongoose instance the model uses.</p></div><hr class="separate-api-elements"><h3 id="model_Model-baseModelName"><a href="#model_Model-baseModelName">Model.prototype.baseModelName</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>If this is a discriminator model, <code>baseModelName</code> is the name of the base model.</p></div><hr class="separate-api-elements"><h3 id="model_Model-collection"><a href="#model_Model-collection">Model.prototype.collection</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Collection the model uses.</p>
-
-<p>This property is read-only. Modifying this property is a no-op.</p></div><hr class="separate-api-elements"><h3 id="model_Model-db"><a href="#model_Model-db">Model.prototype.db</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Connection the model uses.</p></div><hr class="separate-api-elements"><h3 id="model_Model-delete"><a href="#model_Model-delete">Model.prototype.delete</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Alias for remove</p></div><hr class="separate-api-elements"><h3 id="model_Model-deleteOne"><a href="#model_Model-deleteOne">Model.prototype.deleteOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[fn]
-<span class="method-type">&laquo;function(err|product)&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> Promise</li></ul><div><p>Removes this document from the db. Equivalent to <code>.remove()</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product = <span class="hljs-keyword">await</span> product.deleteOne();
-<span class="hljs-keyword">await</span> Product.findById(product._id); <span class="hljs-comment">// null</span></code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-discriminators"><a href="#model_Model-discriminators">Model.prototype.discriminators</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Registered discriminators for this model.</p></div><hr class="separate-api-elements"><h3 id="model_Model-increment"><a href="#model_Model-increment">Model.prototype.increment()</a></h3><div><p>Signal that we desire an increment of this documents version.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  doc.increment();
-  doc.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{ .. })
-})</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-model"><a href="#model_Model-model">Model.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> model name</li></ul><div><p>Returns another Model instance.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> doc = <span class="hljs-keyword">new</span> Tank;
-doc.model(<span class="hljs-string">'User'</span>).findById(id, callback);</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-modelName"><a href="#model_Model-modelName">Model.prototype.modelName</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The name of the model</p></div><hr class="separate-api-elements"><h3 id="model_Model-remove"><a href="#model_Model-remove">Model.prototype.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[fn]
-<span class="method-type">&laquo;function(err|product)&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> Promise</li></ul><div><p>Removes this document from the db.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.remove(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  Product.findById(product._id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(product) <span class="hljs-comment">// null</span>
-  })
-})</code></pre>
-
-<p>As an extra measure of flow control, remove will return a Promise (bound to <code>fn</code> if passed) so it could be chained, or hooked to recieve errors</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.remove().then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">product</span>) </span>{
-   ...
-}).catch(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-   assert.ok(err)
-})</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-save"><a href="#model_Model-save">Model.prototype.save()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> options optional options</li><ul style="margin-top: 0.5em"><li>[options.session=null]
-<span class="method-type">&laquo;Session&raquo;</span> the <a href="https://docs.mongodb.com/manual/reference/server-sessions/">session</a> associated with this save operation. If not specified, defaults to the <a href="api.html#document_Document-$session">document&#39;s associated session</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.safe]
-<span class="method-type">&laquo;Object&raquo;</span> (DEPRECATED) overrides <a href="http://mongoosejs.com//docs/guide.html#safe">schema&#39;s safe option</a>. Use the <code>w</code> option instead.</li></ul><ul style="margin-top: 0.5em"><li>[options.validateBeforeSave]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to save without validating.</li></ul><ul style="margin-top: 0.5em"><li>[options.w]
-<span class="method-type">&laquo;Number|String&raquo;</span> set the <a href="https://docs.mongodb.com/manual/reference/write-concern/#w-option">write concern</a>. Overrides the <a href="/docs/guide.html#writeConcern">schema-level <code>writeConcern</code> option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.j]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to true for MongoDB to wait until this <code>save()</code> has been <a href="https://docs.mongodb.com/manual/reference/write-concern/#j-option">journaled before resolving the returned promise</a>. Overrides the <a href="/docs/guide.html#writeConcern">schema-level <code>writeConcern</code> option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.wtimeout]
-<span class="method-type">&laquo;Number&raquo;</span> sets a <a href="https://docs.mongodb.com/manual/reference/write-concern/#wtimeout">timeout for the write concern</a>. Overrides the <a href="/docs/guide.html#writeConcern">schema-level <code>writeConcern</code> option</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.checkKeys=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> the MongoDB driver prevents you from saving keys that start with &#39;$&#39; or contain &#39;.&#39; by default. Set this option to <code>false</code> to skip that check. See <a href="https://docs.mongodb.com/manual/reference/limits/#Restrictions-on-Field-Names">restrictions on field names</a></li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> if <code>false</code> and <a href="./guide.html#timestamps">timestamps</a> are enabled, skip timestamps for this <code>save()</code>.</li></ul><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns undefined if used with callback or a Promise otherwise.</li></ul><div><p>Saves this document.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.sold = <span class="hljs-built_in">Date</span>.now();
-product = <span class="hljs-keyword">await</span> product.save();</code></pre>
-
-<p>If save is successful, the returned promise will fulfill with the document saved.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> newProduct = <span class="hljs-keyword">await</span> product.save();
-newProduct === product; <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="model_Model-schema"><a href="#model_Model-schema">Model.prototype.schema</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Schema the model uses.</p></div><hr class="separate-api-elements"><h3 id="model_Model.remove"><a href="#model_Model.remove">Model.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Removes all documents that match <code>conditions</code> from the collection. To remove just the first document that matches <code>conditions</code>, set the <code>single</code> option to true.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.remove({ name: <span class="hljs-string">'Eddard Stark'</span> });
-res.deletedCount; <span class="hljs-comment">// Number of documents removed</span></code></pre>
-
-<h4>Note:</h4>
-
-<p>This method sends a remove command directly to MongoDB, no Mongoose documents are involved. Because no Mongoose documents are involved, Mongoose does not execute <a href="/docs/middleware.html#types-of-middleware">document middleware</a>.</p></div><hr class="separate-api-elements"><h3 id="model_Model.replaceOne"><a href="#model_Model.replaceOne">Model.replaceOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> <code>function(error, res) {}</code> where <code>res</code> has 3 properties: <code>n</code>, <code>nModified</code>, <code>ok</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Same as <code>update()</code>, except MongoDB replace the existing document with the given document (no atomic operators like <code>$set</code>).</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.replaceOne({ _id: <span class="hljs-number">24601</span> }, { name: <span class="hljs-string">'Jean Valjean'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>replaceOne()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.startSession"><a href="#model_Model.startSession">Model.startSession()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#startSession">mongodb driver options</a></li><ul style="margin-top: 0.5em"><li>[options.causalConsistency=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to disable causal consistency</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&lt;ClientSession&gt;&raquo;</span> promise that resolves to a MongoDB driver <code>ClientSession</code></li></ul><div><p><em>Requires MongoDB >= 3.6.0.</em> Starts a <a href="https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions">MongoDB session</a> for benefits like causal consistency, <a href="https://docs.mongodb.com/manual/core/retryable-writes/">retryable writes</a>, and <a href="http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html">transactions</a>.</p>
-
-<p>Calling <code>MyModel.startSession()</code> is equivalent to calling <code>MyModel.db.startSession()</code>.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = <span class="hljs-keyword">await</span> Person.startSession();
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session });
-<span class="hljs-keyword">await</span> doc.remove();
-<span class="hljs-comment">// `doc` will always be null, even if reading from a replica set</span>
-<span class="hljs-comment">// secondary. Without causal consistency, it is possible to</span>
-<span class="hljs-comment">// get a doc back from the below query if the query reads from a</span>
-<span class="hljs-comment">// secondary that is experiencing replication lag.</span>
-doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session, readPreference: <span class="hljs-string">'secondary'</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.syncIndexes"><a href="#model_Model.syncIndexes">Model.syncIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> options to pass to <code>ensureIndexes()</code></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns <code>undefined</code> if callback is specified, returns a promise if no callback.</li></ul><div><p>Makes the indexes in MongoDB match the indexes defined in this model's schema. This function will drop any indexes that are not defined in the model's schema except the <code>_id</code> index, and build any indexes that are in your schema but not in MongoDB.</p>
-
-<p>See the <a href="http://thecodebarbarian.com/whats-new-in-mongoose-5-2-syncindexes">introductory blog post</a> for more information.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, unique: <span class="hljs-literal">true</span> } });
-<span class="hljs-keyword">const</span> Customer = mongoose.model(<span class="hljs-string">'Customer'</span>, schema);
-<span class="hljs-keyword">await</span> Customer.createIndex({ age: <span class="hljs-number">1</span> }); <span class="hljs-comment">// Index is not in schema</span>
-<span class="hljs-comment">// Will drop the 'age' index and create an index on `name`</span>
-<span class="hljs-keyword">await</span> Customer.syncIndexes();</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.translateAliases"><a href="#model_Model.translateAliases">Model.translateAliases()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">raw
-<span class="method-type">&laquo;Object&raquo;</span> fields/conditions that may contain aliased keys</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the translated &#39;pure&#39; fields/conditions</li></ul><div><p>Translate any aliases fields/conditions so the final query or document object is pure</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character
-  .find(Character.translateAliases({
-    <span class="hljs-string">'名'</span>: <span class="hljs-string">'Eddard Stark'</span> <span class="hljs-comment">// Alias for 'name'</span>
-  })
-  .exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, characters</span>) </span>{})</code></pre>
-
-<h4>Note:</h4>
-
-<p>Only translate arguments of object type anything else is returned raw</p></div><hr class="separate-api-elements"><h3 id="model_Model.update"><a href="#model_Model.update">Model.update()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.multi=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> whether multiple documents should be updated or just the first one that matches <code>filter</code>.</li></ul><ul style="margin-top: 0.5em"><li>[options.runValidators=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model&#39;s schema.</li></ul><ul style="margin-top: 0.5em"><li>[options.setDefaultsOnInsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model&#39;s schema if a new document is created. This option only works on MongoDB &gt;= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB&#39;s <code>$setOnInsert</code> operator</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><ul style="margin-top: 0.5em"><li>[options.overwrite=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> By default, if you don&#39;t include any <a href="https://docs.mongodb.com/manual/reference/operator/update/">update operators</a> in <code>doc</code>, Mongoose will wrap <code>doc</code> in <code>$set</code> for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding <code>$set</code>.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Updates one document in the database without returning it.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>update()</code></li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>MyModel.update({ age: { $gt: <span class="hljs-number">18</span> } }, { oldEnough: <span class="hljs-literal">true</span> }, fn);
-
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> MyModel.update({ name: <span class="hljs-string">'Tobi'</span> }, { ferret: <span class="hljs-literal">true</span> });
-res.n; <span class="hljs-comment">// Number of documents that matched `{ name: 'Tobi' }`</span>
-<span class="hljs-comment">// Number of documents that were changed. If every doc matched already</span>
-<span class="hljs-comment">// had `ferret` set to `true`, `nModified` will be 0.</span>
-res.nModified;</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li><code>strict</code> (boolean): overrides the <a href="/docs/guide.html#strict">schema-level <code>strict</code> option</a> for this update</li>
-<li><code>upsert</code> (boolean): whether to create the doc if it doesn't match (false)</li>
-<li><code>writeConcern</code> (object): sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li>
-<li><code>omitUndefined</code> (boolean): If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: 'bar', baz: undefined })</code> before sending the update to the server.</li>
-<li><code>multi</code> (boolean): whether multiple documents should be updated (false)</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code> (boolean): if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>timestamps</code> (boolean): If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li>
-<li><code>overwrite</code> (boolean): disables update-only mode, allowing you to overwrite the doc (false)</li>
-</ul>
-
-<p>All <code>update</code> values are cast to their appropriate SchemaTypes before being sent.</p>
-
-<p>The <code>callback</code> function receives <code>(err, rawResponse)</code>.</p>
-
-<ul>
-<li><code>err</code> is the error if any occurred</li>
-<li><code>rawResponse</code> is the full response from Mongo</li>
-</ul>
-
-<h4>Note:</h4>
-
-<p>All top level keys which are not <code>atomic</code> operation names are treated as set operations:</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = { name: <span class="hljs-string">'borne'</span> };
-Model.update(query, { name: <span class="hljs-string">'jason bourne'</span> }, options, callback);
-
-<span class="hljs-comment">// is sent as</span>
-Model.update(query, { $set: { name: <span class="hljs-string">'jason bourne'</span> }}, options, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, res</span>));
-// <span class="hljs-title">if</span> <span class="hljs-title">overwrite</span> <span class="hljs-title">option</span> <span class="hljs-title">is</span> <span class="hljs-title">false</span>. <span class="hljs-title">If</span> <span class="hljs-title">overwrite</span> <span class="hljs-title">is</span> <span class="hljs-title">true</span>, <span class="hljs-title">sent</span> <span class="hljs-title">without</span> <span class="hljs-title">the</span> <span class="hljs-title">$set</span> <span class="hljs-title">wrapper</span>.
-</span></code></pre>
-
-<p>This helps prevent accidentally overwriting all documents in your collection with <code>{ name: 'jason bourne' }</code>.</p>
-
-<h4>Note:</h4>
-
-<p>Be careful to not use an existing model instance for the update clause (this won't work and can cause weird behavior like infinite loops). Also, ensure that the update clause does not have an _id property, which causes Mongo to return a "Mod on _id not allowed" error.</p>
-
-<h4>Note:</h4>
-
-<p>Mongoose casts values and runs setters when using update. The following features are <strong>not</strong> applied by default.</p>
-
-<ul>
-<li><a href="/docs/defaults.html#the-setdefaultsoninsert-option">defaults</a></li>
-<li><a href="/docs/validation.html#update-validators">validators</a></li>
-<li>middleware</li>
-</ul>
-
-<p>If you need document middleware and fully-featured validation, load the document first and then use <a href="/docs/api.html#model_Model-save"><code>save()</code></a>.</p>
-
-<pre><code>Model.findOne({ name: <span class="hljs-string">'borne'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-})</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.updateMany"><a href="#model_Model.updateMany">Model.updateMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> <code>function(error, res) {}</code> where <code>res</code> has 3 properties: <code>n</code>, <code>nModified</code>, <code>ok</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Same as <code>update()</code>, except MongoDB will update <em>all</em> documents that match <code>filter</code> (as opposed to just the first one) regardless of the value of the <code>multi</code> option.</p>
-
-<p><strong>Note</strong> updateMany will <em>not</em> fire update middleware. Use <code>pre('updateMany')</code> and <code>post('updateMany')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateMany({ name: <span class="hljs-regexp">/Stark$/</span> }, { isDeleted: <span class="hljs-literal">true</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateMany()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.updateOne"><a href="#model_Model.updateOne">Model.updateOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Same as <code>update()</code>, except it does not support the <code>multi</code> or <code>overwrite</code> options.</p>
-
-<ul>
-<li>MongoDB will update <em>only</em> the first document that matches <code>filter</code> regardless of the value of the <code>multi</code> option.</li>
-<li>Use <code>replaceOne()</code> if you want to overwrite an entire document rather than using atomic operators like <code>$set</code>.</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateOne({ name: <span class="hljs-string">'Jean-Luc Picard'</span> }, { ship: <span class="hljs-string">'USS Enterprise'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateOne()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="model_Model.watch"><a href="#model_Model.watch">Model.watch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[pipeline]
-<span class="method-type">&laquo;Array&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/Collection.html#watch">mongodb driver options</a></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ChangeStream&raquo;</span> mongoose-specific change stream wrapper, inherits from EventEmitter</li></ul><div><p><em>Requires a replica set running MongoDB >= 3.6.0.</em> Watches the underlying collection for changes using <a href="https://docs.mongodb.com/manual/changeStreams/">MongoDB change streams</a>.</p>
-
-<p>This function does <strong>not</strong> trigger any middleware. In particular, it does <strong>not</strong> trigger aggregate middleware.</p>
-
-<h2>The ChangeStream object is an event emitter that emits the following events</h2>
-
-<ul>
-<li>'change': A change occurred, see below example</li>
-<li>'error': An unrecoverable error occurred. In particular, change streams currently error out if they lose connection to the replica set primary. Follow <a href="https://github.com/Automattic/mongoose/issues/6799">this GitHub issue</a> for updates.</li>
-<li>'end': Emitted if the underlying stream is closed</li>
-<li>'close': Emitted if the underlying stream is closed</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Person.create({ name: <span class="hljs-string">'Ned Stark'</span> });
-<span class="hljs-keyword">const</span> changeStream = Person.watch().on(<span class="hljs-string">'change'</span>, change =&gt; <span class="hljs-built_in">console</span>.log(change));
-<span class="hljs-comment">// Will print from the above `console.log()`:</span>
-<span class="hljs-comment">// { _id: { _data: ... },</span>
-<span class="hljs-comment">//   operationType: 'delete',</span>
-<span class="hljs-comment">//   ns: { db: 'mydb', coll: 'Person' },</span>
-<span class="hljs-comment">//   documentKey: { _id: 5a51b125c5500f5aa094c7bd } }</span>
-<span class="hljs-keyword">await</span> doc.remove();</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.where"><a href="#model_Model.where">Model.where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[val]
-<span class="method-type">&laquo;Object&raquo;</span> optional value</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Creates a Query, applies the passed conditions, and returns the Query.</p>
-
-<p>For example, instead of writing:</p>
-
-<pre><code>User.find({age: {$gte: <span class="hljs-number">21</span>, $lte: <span class="hljs-number">65</span>}}, callback);</code></pre>
-
-<p>we can instead write:</p>
-
-<pre><code>User.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>).exec(callback);</code></pre>
-
-<p>Since the Query class also supports <code>where</code> you can continue chaining</p>
-
-<pre><code>User
-.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>)
-.where(<span class="hljs-string">'name'</span>, <span class="hljs-regexp">/^b/i</span>)
-... etc</code></pre></div><hr class="separate-api-elements"><h3 id="model_Model.inspect"><a href="#model_Model.inspect">function Object() { [native code] }.prototype.inspect()</a></h3><div><p>Helper for console.log</p></div><hr class="separate-api"><h2 class="item-header" id="Query"><a href="#Query">Query</a></h2><ul><li><a href="#query_Query">Query()</a></li><li><a href="#query_Query-$where">Query.prototype.$where()</a></li><li><a href="#query_Query-Symbol.asyncIterator">Query.prototype.Symbol.asyncIterator()</a></li><li><a href="#query_Query-all">Query.prototype.all()</a></li><li><a href="#query_Query-and">Query.prototype.and()</a></li><li><a href="#query_Query-batchSize">Query.prototype.batchSize()</a></li><li><a href="#query_Query-box">Query.prototype.box()</a></li><li><a href="#query_Query-cast">Query.prototype.cast()</a></li><li><a href="#query_Query-catch">Query.prototype.catch()</a></li><li><a href="#query_Query-center">Query.prototype.center()</a></li><li><a href="#query_Query-centerSphere">Query.prototype.centerSphere()</a></li><li><a href="#query_Query-circle">Query.prototype.circle()</a></li><li><a href="#query_Query-collation">Query.prototype.collation()</a></li><li><a href="#query_Query-comment">Query.prototype.comment()</a></li><li><a href="#query_Query-count">Query.prototype.count()</a></li><li><a href="#query_Query-countDocuments">Query.prototype.countDocuments()</a></li><li><a href="#query_Query-cursor">Query.prototype.cursor()</a></li><li><a href="#query_Query-deleteMany">Query.prototype.deleteMany()</a></li><li><a href="#query_Query-deleteOne">Query.prototype.deleteOne()</a></li><li><a href="#query_Query-distinct">Query.prototype.distinct()</a></li><li><a href="#query_Query-elemMatch">Query.prototype.elemMatch()</a></li><li><a href="#query_Query-equals">Query.prototype.equals()</a></li><li><a href="#query_Query-error">Query.prototype.error()</a></li><li><a href="#query_Query-estimatedDocumentCount">Query.prototype.estimatedDocumentCount()</a></li><li><a href="#query_Query-exec">Query.prototype.exec()</a></li><li><a href="#query_Query-exists">Query.prototype.exists()</a></li><li><a href="#query_Query-explain">Query.prototype.explain()</a></li><li><a href="#query_Query-find">Query.prototype.find()</a></li><li><a href="#query_Query-findOne">Query.prototype.findOne()</a></li><li><a href="#query_Query-findOneAndDelete">Query.prototype.findOneAndDelete()</a></li><li><a href="#query_Query-findOneAndRemove">Query.prototype.findOneAndRemove()</a></li><li><a href="#query_Query-findOneAndReplace">Query.prototype.findOneAndReplace()</a></li><li><a href="#query_Query-findOneAndUpdate">Query.prototype.findOneAndUpdate()</a></li><li><a href="#query_Query-geometry">Query.prototype.geometry()</a></li><li><a href="#query_Query-getFilter">Query.prototype.getFilter()</a></li><li><a href="#query_Query-getOptions">Query.prototype.getOptions()</a></li><li><a href="#query_Query-getPopulatedPaths">Query.prototype.getPopulatedPaths()</a></li><li><a href="#query_Query-getQuery">Query.prototype.getQuery()</a></li><li><a href="#query_Query-getUpdate">Query.prototype.getUpdate()</a></li><li><a href="#query_Query-gt">Query.prototype.gt()</a></li><li><a href="#query_Query-gte">Query.prototype.gte()</a></li><li><a href="#query_Query-hint">Query.prototype.hint()</a></li><li><a href="#query_Query-in">Query.prototype.in()</a></li><li><a href="#query_Query-intersects">Query.prototype.intersects()</a></li><li><a href="#query_Query-j">Query.prototype.j()</a></li><li><a href="#query_Query-lean">Query.prototype.lean()</a></li><li><a href="#query_Query-limit">Query.prototype.limit()</a></li><li><a href="#query_Query-lt">Query.prototype.lt()</a></li><li><a href="#query_Query-lte">Query.prototype.lte()</a></li><li><a href="#query_Query-map">Query.prototype.map()</a></li><li><a href="#query_Query-maxDistance">Query.prototype.maxDistance()</a></li><li><a href="#query_Query-maxScan">Query.prototype.maxScan()</a></li><li><a href="#query_Query-maxTimeMS">Query.prototype.maxTimeMS()</a></li><li><a href="#query_Query-maxscan">Query.prototype.maxscan()</a></li><li><a href="#query_Query-merge">Query.prototype.merge()</a></li><li><a href="#query_Query-mod">Query.prototype.mod()</a></li><li><a href="#query_Query-mongooseOptions">Query.prototype.mongooseOptions()</a></li><li><a href="#query_Query-ne">Query.prototype.ne()</a></li><li><a href="#query_Query-near">Query.prototype.near()</a></li><li><a href="#query_Query-nearSphere">Query.prototype.nearSphere()</a></li><li><a href="#query_Query-nin">Query.prototype.nin()</a></li><li><a href="#query_Query-nor">Query.prototype.nor()</a></li><li><a href="#query_Query-or">Query.prototype.or()</a></li><li><a href="#query_Query-orFail">Query.prototype.orFail()</a></li><li><a href="#query_Query-polygon">Query.prototype.polygon()</a></li><li><a href="#query_Query-populate">Query.prototype.populate()</a></li><li><a href="#query_Query-projection">Query.prototype.projection()</a></li><li><a href="#query_Query-read">Query.prototype.read()</a></li><li><a href="#query_Query-readConcern">Query.prototype.readConcern()</a></li><li><a href="#query_Query-regex">Query.prototype.regex()</a></li><li><a href="#query_Query-remove">Query.prototype.remove()</a></li><li><a href="#query_Query-replaceOne">Query.prototype.replaceOne()</a></li><li><a href="#query_Query-select">Query.prototype.select()</a></li><li><a href="#query_Query-selected">Query.prototype.selected()</a></li><li><a href="#query_Query-selectedExclusively">Query.prototype.selectedExclusively()</a></li><li><a href="#query_Query-selectedInclusively">Query.prototype.selectedInclusively()</a></li><li><a href="#query_Query-session">Query.prototype.session()</a></li><li><a href="#query_Query-set">Query.prototype.set()</a></li><li><a href="#query_Query-setOptions">Query.prototype.setOptions()</a></li><li><a href="#query_Query-setQuery">Query.prototype.setQuery()</a></li><li><a href="#query_Query-setUpdate">Query.prototype.setUpdate()</a></li><li><a href="#query_Query-size">Query.prototype.size()</a></li><li><a href="#query_Query-skip">Query.prototype.skip()</a></li><li><a href="#query_Query-slaveOk">Query.prototype.slaveOk()</a></li><li><a href="#query_Query-slice">Query.prototype.slice()</a></li><li><a href="#query_Query-snapshot">Query.prototype.snapshot()</a></li><li><a href="#query_Query-sort">Query.prototype.sort()</a></li><li><a href="#query_Query-tailable">Query.prototype.tailable()</a></li><li><a href="#query_Query-then">Query.prototype.then()</a></li><li><a href="#query_Query-toConstructor">Query.prototype.toConstructor()</a></li><li><a href="#query_Query-update">Query.prototype.update()</a></li><li><a href="#query_Query-updateMany">Query.prototype.updateMany()</a></li><li><a href="#query_Query-updateOne">Query.prototype.updateOne()</a></li><li><a href="#query_Query-use$geoWithin">Query.prototype.use$geoWithin</a></li><li><a href="#query_Query-w">Query.prototype.w()</a></li><li><a href="#query_Query-where">Query.prototype.where()</a></li><li><a href="#query_Query-within">Query.prototype.within()</a></li><li><a href="#query_Query-wtimeout">Query.prototype.wtimeout()</a></li></ul><hr class="separate-api-elements"><h3 id="query_Query"><a href="#query_Query">Query()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[model]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[collection]
-<span class="method-type">&laquo;Object&raquo;</span> Mongoose collection</li></ul><div><p>Query constructor used for building queries. You do not need to instantiate a <code>Query</code> directly. Instead use Model functions like <a href="/docs/api.html#find_find"><code>Model.find()</code></a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = MyModel.find(); <span class="hljs-comment">// `query` is an instance of `Query`</span>
-query.setOptions({ lean : <span class="hljs-literal">true</span> });
-query.collection(MyModel.collection);
-query.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).exec(callback);
-
-<span class="hljs-comment">// You can instantiate a query directly. There is no need to do</span>
-<span class="hljs-comment">// this unless you're an advanced user with a very good reason to.</span>
-<span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> mongoose.Query();</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-$where"><a href="#query_Query-$where">Query.prototype.$where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">js
-<span class="method-type">&laquo;String|Function&raquo;</span> javascript string or function</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a javascript function or expression to pass to MongoDBs query system.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.$where(<span class="hljs-string">'this.comments.length === 10 || this.name.length === 5'</span>)
-
-<span class="hljs-comment">// or</span>
-
-query.$where(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.comments.length === <span class="hljs-number">10</span> || <span class="hljs-keyword">this</span>.name.length === <span class="hljs-number">5</span>;
-})</code></pre>
-
-<h4>NOTE:</h4>
-
-<p>Only use <code>$where</code> when you have a condition that cannot be met using other MongoDB operators like <code>$lt</code>. <strong>Be sure to read about all of <a href="http://docs.mongodb.org/manual/reference/operator/where/">its caveats</a> before using.</strong></p></div><hr class="separate-api-elements"><h3 id="query_Query-Symbol.asyncIterator"><a href="#query_Query-Symbol.asyncIterator">Query.prototype.Symbol.asyncIterator()</a></h3><div><p>Returns an asyncIterator for use with <a href="http://bit.ly/async-iterators"><code>for/await/of</code> loops</a> This function <em>only</em> works for <code>find()</code> queries. You do not need to call this function explicitly, the JavaScript runtime will call it for you.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> doc <span class="hljs-keyword">of</span> Model.aggregate([{ $sort: { name: <span class="hljs-number">1</span> } }])) {
-  <span class="hljs-built_in">console</span>.log(doc.name);
-}</code></pre>
-
-<p>Node.js 10.x supports async iterators natively without any flags. You can enable async iterators in Node.js 8.x using the <a href="https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187"><code>--harmony_async_iteration</code> flag</a>.</p>
-
-<p><strong>Note:</strong> This function is not if <code>Symbol.asyncIterator</code> is undefined. If <code>Symbol.asyncIterator</code> is undefined, that means your Node.js version does not support async iterators.</p></div><hr class="separate-api-elements"><h3 id="query_Query-all"><a href="#query_Query-all">Query.prototype.all()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Specifies an <code>$all</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>
-
-<h4>Example:</h4>
-
-<pre><code>MyModel.find().where(<span class="hljs-string">'pets'</span>).all([<span class="hljs-string">'dog'</span>, <span class="hljs-string">'cat'</span>, <span class="hljs-string">'ferret'</span>]);
-<span class="hljs-comment">// Equivalent:</span>
-MyModel.find().all(<span class="hljs-string">'pets'</span>, [<span class="hljs-string">'dog'</span>, <span class="hljs-string">'cat'</span>, <span class="hljs-string">'ferret'</span>]);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-and"><a href="#query_Query-and">Query.prototype.and()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">array
-<span class="method-type">&laquo;Array&raquo;</span> array of conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies arguments for a <code>$and</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.and([{ color: <span class="hljs-string">'green'</span> }, { status: <span class="hljs-string">'ok'</span> }])</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-batchSize"><a href="#query_Query-batchSize">Query.prototype.batchSize()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the batchSize option.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.batchSize(<span class="hljs-number">100</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-box"><a href="#query_Query-box">Query.prototype.box()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">Upper
-<span class="method-type">&laquo;[Array]&raquo;</span> Right Coords</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$box</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> lowerLeft = [<span class="hljs-number">40.73083</span>, <span class="hljs-number">-73.99756</span>]
-<span class="hljs-keyword">var</span> upperRight= [<span class="hljs-number">40.741404</span>,  <span class="hljs-number">-73.988135</span>]
-
-query.where(<span class="hljs-string">'loc'</span>).within().box(lowerLeft, upperRight)
-query.box({ ll : lowerLeft, ur : upperRight })</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-cast"><a href="#query_Query-cast">Query.prototype.cast()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[model]
-<span class="method-type">&laquo;Model&raquo;</span> the model to cast to. If not set, defaults to <code>this.model</code></li><li class="param">[obj]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Casts this query to the schema of <code>model</code></p>
-
-<h4>Note</h4>
-
-<p>If <code>obj</code> is present, it is cast instead of this query.</p></div><hr class="separate-api-elements"><h3 id="query_Query-catch"><a href="#query_Query-catch">Query.prototype.catch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query returning a <code>Promise</code> which will be resolved with either the doc(s) or rejected with the error. Like <code>.then()</code>, but only takes a rejection handler.</p></div><hr class="separate-api-elements"><h3 id="query_Query-center"><a href="#query_Query-center">Query.prototype.center()</a></h3><div><p><em>DEPRECATED</em> Alias for <a href="#query_Query-circle">circle</a></p>
-
-<p><strong>Deprecated.</strong> Use <a href="#query_Query-circle">circle</a> instead.</p></div><hr class="separate-api-elements"><h3 id="query_Query-centerSphere"><a href="#query_Query-centerSphere">Query.prototype.centerSphere()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p><em>DEPRECATED</em> Specifies a <code>$centerSphere</code> condition</p>
-
-<p><strong>Deprecated.</strong> Use <a href="#query_Query-circle">circle</a> instead.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> area = { center: [<span class="hljs-number">50</span>, <span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span> };
-query.where(<span class="hljs-string">'loc'</span>).within().centerSphere(area);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-circle"><a href="#query_Query-circle">Query.prototype.circle()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">area
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$center</code> or <code>$centerSphere</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> area = { center: [<span class="hljs-number">50</span>, <span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span>, unique: <span class="hljs-literal">true</span> }
-query.where(<span class="hljs-string">'loc'</span>).within().circle(area)
-<span class="hljs-comment">// alternatively</span>
-query.circle(<span class="hljs-string">'loc'</span>, area);
-
-<span class="hljs-comment">// spherical calculations</span>
-<span class="hljs-keyword">var</span> area = { center: [<span class="hljs-number">50</span>, <span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span>, unique: <span class="hljs-literal">true</span>, spherical: <span class="hljs-literal">true</span> }
-query.where(<span class="hljs-string">'loc'</span>).within().circle(area)
-<span class="hljs-comment">// alternatively</span>
-query.circle(<span class="hljs-string">'loc'</span>, area);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-collation"><a href="#query_Query-collation">Query.prototype.collation()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Adds a collation to this op (MongoDB 3.4 and up)</p></div><hr class="separate-api-elements"><h3 id="query_Query-comment"><a href="#query_Query-comment">Query.prototype.comment()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Specifies the <code>comment</code> option.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.comment(<span class="hljs-string">'login query'</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-count"><a href="#query_Query-count">Query.prototype.count()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> count documents that match this object</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, count)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>count</code> query.</p>
-
-<p>This method is deprecated. If you want to count the number of documents in a collection, e.g. <code>count({})</code>, use the <a href="/docs/api.html#query_Query-estimatedDocumentCount"><code>estimatedDocumentCount()</code> function</a> instead. Otherwise, use the <a href="/docs/api.html#query_Query-countDocuments"><code>countDocuments()</code></a> function instead.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>count()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> countQuery = model.where({ <span class="hljs-string">'color'</span>: <span class="hljs-string">'black'</span> }).count();
-
-query.count({ color: <span class="hljs-string">'black'</span> }).count(callback)
-
-query.count({ color: <span class="hljs-string">'black'</span> }, callback)
-
-query.where(<span class="hljs-string">'color'</span>, <span class="hljs-string">'black'</span>).count(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d kittens'</span>, count);
-})</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-countDocuments"><a href="#query_Query-countDocuments">Query.prototype.countDocuments()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, count)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>countDocuments()</code> query. Behaves like <code>count()</code>, except it always does a full collection scan when passed an empty filter <code>{}</code>.</p>
-
-<p>There are also minor differences in how <code>countDocuments()</code> handles <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments"><code>$where</code> and a couple geospatial operators</a>. versus <code>count()</code>.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>countDocuments()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> countQuery = model.where({ <span class="hljs-string">'color'</span>: <span class="hljs-string">'black'</span> }).countDocuments();
-
-query.countDocuments({ color: <span class="hljs-string">'black'</span> }).count(callback);
-
-query.countDocuments({ color: <span class="hljs-string">'black'</span> }, callback);
-
-query.where(<span class="hljs-string">'color'</span>, <span class="hljs-string">'black'</span>).countDocuments(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d kittens'</span>, count);
-});</code></pre>
-
-<p>The <code>countDocuments()</code> function is similar to <code>count()</code>, but there are a <a href="https://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments">few operators that <code>countDocuments()</code> does not support</a>. Below are the operators that <code>count()</code> supports but <code>countDocuments()</code> does not, and the suggested replacement:</p>
-
-<ul>
-<li><code>$where</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/expr/"><code>$expr</code></a></li>
-<li><code>$near</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/center/#op._S_center"><code>$center</code></a></li>
-<li><code>$nearSphere</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/centerSphere/#op._S_centerSphere"><code>$centerSphere</code></a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="query_Query-cursor"><a href="#query_Query-cursor">Query.prototype.cursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;QueryCursor&raquo;</span> </li></ul><div><p>Returns a wrapper around a <a href="http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html">mongodb driver cursor</a>. A QueryCursor exposes a Streams3 interface, as well as a <code>.next()</code> function.</p>
-
-<p>The <code>.cursor()</code> function triggers pre find hooks, but <strong>not</strong> post find hooks.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// There are 2 ways to use a cursor. First, as a stream:</span>
-Thing.
-  find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{ <span class="hljs-built_in">console</span>.log(doc); }).
-  on(<span class="hljs-string">'end'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Done!'</span>); });
-
-<span class="hljs-comment">// Or you can use `.next()` to manually get the next doc in the stream.</span>
-<span class="hljs-comment">// `.next()` returns a promise, so you can use promises or callbacks.</span>
-<span class="hljs-keyword">var</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).cursor();
-cursor.next(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc);
-});
-
-<span class="hljs-comment">// Because `.next()` returns a promise, you can use co</span>
-<span class="hljs-comment">// to easily iterate through all documents without loading them</span>
-<span class="hljs-comment">// all into memory.</span>
-co(<span class="hljs-function"><span class="hljs-keyword">function</span>*(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">const</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).cursor();
-  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">yield</span> cursor.next(); doc != <span class="hljs-literal">null</span>; doc = <span class="hljs-keyword">yield</span> cursor.next()) {
-    <span class="hljs-built_in">console</span>.log(doc);
-  }
-});</code></pre>
-
-<h4>Valid options</h4>
-
-<ul>
-<li><code>transform</code>: optional function which accepts a mongoose document. The return value of the function will be emitted on <code>data</code> and returned by <code>.next()</code>.</li>
-</ul></div><hr class="separate-api-elements"><h3 id="query_Query-deleteMany"><a href="#query_Query-deleteMany">Query.prototype.deleteMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, mongooseDeleteResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a <code>deleteMany()</code> operation. Works like remove, except it deletes <em>every</em> document that matches <code>filter</code> in the collection, regardless of the value of <code>single</code>.</p>
-
-<p>This function does not trigger any middleware</p>
-
-<h4>Example</h4>
-
-<pre><code>Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } }, callback)
-Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } }).then(next)</code></pre>
-
-<p>This function calls the MongoDB driver's <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#deleteMany"><code>Collection#deleteMany()</code> function</a>. The returned <a href="https://mongoosejs.com/docs/queries.html">promise</a> resolves to an object that contains 3 properties:</p>
-
-<ul>
-<li><code>ok</code>: <code>1</code> if no errors occurred</li>
-<li><code>deletedCount</code>: the number of documents deleted</li>
-<li><code>n</code>: the number of documents deleted. Equal to <code>deletedCount</code>.</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } });
-<span class="hljs-comment">// `0` if no docs matched the filter, number of docs deleted otherwise</span>
-res.deletedCount;</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-deleteOne"><a href="#query_Query-deleteOne">Query.prototype.deleteOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, mongooseDeleteResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a <code>deleteOne()</code> operation. Works like remove, except it deletes at most one document regardless of the <code>single</code> option.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example</h4>
-
-<pre><code>Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> }, callback);
-Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> }).then(next);</code></pre>
-
-<p>This function calls the MongoDB driver's <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#deleteOne"><code>Collection#deleteOne()</code> function</a>. The returned <a href="https://mongoosejs.com/docs/queries.html">promise</a> resolves to an object that contains 3 properties:</p>
-
-<ul>
-<li><code>ok</code>: <code>1</code> if no errors occurred</li>
-<li><code>deletedCount</code>: the number of documents deleted</li>
-<li><code>n</code>: the number of documents deleted. Equal to <code>deletedCount</code>.</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> });
-<span class="hljs-comment">// `1` if MongoDB deleted a doc, `0` if no docs matched the filter `{ name: ... }`</span>
-res.deletedCount;</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-distinct"><a href="#query_Query-distinct">Query.prototype.distinct()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[field]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, arr)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declares or executes a distinct() operation.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example</h4>
-
-<pre><code>distinct(field, conditions, callback)
-distinct(field, conditions)
-distinct(field, callback)
-distinct(field)
-distinct(callback)
-distinct()</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-elemMatch"><a href="#query_Query-elemMatch">Query.prototype.elemMatch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object|Function&raquo;</span> </li><li class="param">filter
-<span class="method-type">&laquo;Object|Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies an <code>$elemMatch</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code>query.elemMatch(<span class="hljs-string">'comment'</span>, { author: <span class="hljs-string">'autobot'</span>, votes: {$gte: <span class="hljs-number">5</span>}})
-
-query.where(<span class="hljs-string">'comment'</span>).elemMatch({ author: <span class="hljs-string">'autobot'</span>, votes: {$gte: <span class="hljs-number">5</span>}})
-
-query.elemMatch(<span class="hljs-string">'comment'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">elem</span>) </span>{
-  elem.where(<span class="hljs-string">'author'</span>).equals(<span class="hljs-string">'autobot'</span>);
-  elem.where(<span class="hljs-string">'votes'</span>).gte(<span class="hljs-number">5</span>);
-})
-
-query.where(<span class="hljs-string">'comment'</span>).elemMatch(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">elem</span>) </span>{
-  elem.where({ author: <span class="hljs-string">'autobot'</span> });
-  elem.where(<span class="hljs-string">'votes'</span>).gte(<span class="hljs-number">5</span>);
-})</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-equals"><a href="#query_Query-equals">Query.prototype.equals()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies the complementary comparison value for paths specified with <code>where()</code></p>
-
-<h4>Example</h4>
-
-<pre><code>User.where(<span class="hljs-string">'age'</span>).equals(<span class="hljs-number">49</span>);
-
-<span class="hljs-comment">// is the same as</span>
-
-User.where(<span class="hljs-string">'age'</span>, <span class="hljs-number">49</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-error"><a href="#query_Query-error">Query.prototype.error()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">err
-<span class="method-type">&laquo;Error|null&raquo;</span> if set, <code>exec()</code> will fail fast before sending the query to MongoDB</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Gets/sets the error flag on this query. If this flag is not null or undefined, the <code>exec()</code> promise will reject without executing.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Query().error(); <span class="hljs-comment">// Get current error value</span>
-Query().error(<span class="hljs-literal">null</span>); <span class="hljs-comment">// Unset the current error</span>
-Query().error(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'test'</span>)); <span class="hljs-comment">// `exec()` will resolve with test</span>
-Schema.pre(<span class="hljs-string">'find'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.getQuery().userId) {
-    <span class="hljs-keyword">this</span>.error(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Not allowed to query without setting userId'</span>));
-  }
-});</code></pre>
-
-<p>Note that query casting runs <strong>after</strong> hooks, so cast errors will override custom errors.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> TestSchema = <span class="hljs-keyword">new</span> Schema({ num: <span class="hljs-built_in">Number</span> });
-<span class="hljs-keyword">var</span> TestModel = db.model(<span class="hljs-string">'Test'</span>, TestSchema);
-TestModel.find({ num: <span class="hljs-string">'not a number'</span> }).error(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'woops'</span>)).exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// `error` will be a cast error because `num` failed to cast</span>
-});</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-estimatedDocumentCount"><a href="#query_Query-estimatedDocumentCount">Query.prototype.estimatedDocumentCount()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> passed transparently to the <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#estimatedDocumentCount">MongoDB driver</a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, count)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>estimatedDocumentCount()</code> query. Faster than using <code>countDocuments()</code> for large collections because <code>estimatedDocumentCount()</code> uses collection metadata rather than scanning the entire collection.</p>
-
-<p><code>estimatedDocumentCount()</code> does <strong>not</strong> accept a filter. <code>Model.find({ foo: bar }).estimatedDocumentCount()</code> is equivalent to <code>Model.find().estimatedDocumentCount()</code></p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>estimatedDocumentCount()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> Model.find().estimatedDocumentCount();</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-exec"><a href="#query_Query-exec">Query.prototype.exec()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[operation]
-<span class="method-type">&laquo;String|Function&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params depend on the function being called</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> promise = query.exec();
-<span class="hljs-keyword">var</span> promise = query.exec(<span class="hljs-string">'update'</span>);
-
-query.exec(callback);
-query.exec(<span class="hljs-string">'find'</span>, callback);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-exists"><a href="#query_Query-exists">Query.prototype.exists()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies an <code>$exists</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// { name: { $exists: true }}</span>
-Thing.where(<span class="hljs-string">'name'</span>).exists()
-Thing.where(<span class="hljs-string">'name'</span>).exists(<span class="hljs-literal">true</span>)
-Thing.find().exists(<span class="hljs-string">'name'</span>)
-
-<span class="hljs-comment">// { name: { $exists: false }}</span>
-Thing.where(<span class="hljs-string">'name'</span>).exists(<span class="hljs-literal">false</span>);
-Thing.find().exists(<span class="hljs-string">'name'</span>, <span class="hljs-literal">false</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-explain"><a href="#query_Query-explain">Query.prototype.explain()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[verbose]
-<span class="method-type">&laquo;String&raquo;</span> The verbosity mode. Either &#39;queryPlanner&#39;, &#39;executionStats&#39;, or &#39;allPlansExecution&#39;. The default is &#39;queryPlanner&#39;</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the <a href="https://docs.mongodb.com/manual/reference/method/cursor.explain/"><code>explain</code> option</a>, which makes this query return detailed execution stats instead of the actual query result. This method is useful for determining what index your queries use.</p>
-
-<p>Calling <code>query.explain(v)</code> is equivalent to <code>query.setOption({ explain: v })</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> Query();
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> query.find({ a: <span class="hljs-number">1</span> }).explain(<span class="hljs-string">'queryPlanner'</span>);
-<span class="hljs-built_in">console</span>.log(res);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-find"><a href="#query_Query-find">Query.prototype.find()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> mongodb selector. If not specified, returns all documents.</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Find all documents that match <code>selector</code>. The result will be an array of documents.</p>
-
-<p>If there are too many documents in the result to fit in memory, use <a href="api.html#query_Query-cursor"><code>Query.prototype.cursor()</code></a></p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Using async/await</span>
-<span class="hljs-keyword">const</span> arr = <span class="hljs-keyword">await</span> Movie.find({ year: { $gte: <span class="hljs-number">1980</span>, $lte: <span class="hljs-number">1989</span> } });
-
-<span class="hljs-comment">// Using callbacks</span>
-Movie.find({ year: { $gte: <span class="hljs-number">1980</span>, $lte: <span class="hljs-number">1989</span> } }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, arr</span>) </span>{});</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-findOne"><a href="#query_Query-findOne">Query.prototype.findOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> mongodb selector</li><li class="param">[projection]
-<span class="method-type">&laquo;Object&raquo;</span> optional fields to return</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declares the query a findOne operation. When executed, the first found document is passed to the callback.</p>
-
-<p>Passing a <code>callback</code> executes the query. The result of the query is a single document.</p>
-
-<ul>
-<li><em>Note:</em> <code>conditions</code> is optional, and if <code>conditions</code> is null or undefined,
-mongoose will send an empty <code>findOne</code> command to MongoDB, which will return
-an arbitrary document. If you're querying by <code>_id</code>, use <code>Model.findById()</code>
-instead.</li>
-</ul>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOne()</code></li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query  = Kitten.where({ color: <span class="hljs-string">'white'</span> });
-query.findOne(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kitten</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-keyword">if</span> (kitten) {
-    <span class="hljs-comment">// doc may be null if no document matched</span>
-  }
-});</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndDelete"><a href="#query_Query-findOneAndDelete">Query.prototype.findOneAndDelete()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a MongoDB <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findOneAndDelete/">findOneAndDelete</a> command.</p>
-
-<p>Finds a matching document, removes it, and passes the found document (if any) to the callback. Executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndDelete()</code></li>
-</ul>
-
-<p>This function differs slightly from <code>Model.findOneAndRemove()</code> in that <code>findOneAndRemove()</code> becomes a <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/">MongoDB <code>findAndModify()</code> command</a>, as opposed to a <code>findOneAndDelete()</code> command. For most mongoose use cases, this distinction is purely pedantic. You should use <code>findOneAndDelete()</code> unless you have a good reason not to.</p>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>rawResult</code>: if true, resolves to the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>A.where().findOneAndDelete(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndDelete(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.where().findOneAndDelete(conditions, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndDelete(conditions) <span class="hljs-comment">// returns Query</span>
-A.where().findOneAndDelete(callback)   <span class="hljs-comment">// executes</span>
-A.where().findOneAndDelete()           <span class="hljs-comment">// returns Query</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndRemove"><a href="#query_Query-findOneAndRemove">Query.prototype.findOneAndRemove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a mongodb <a href="http://www.mongodb.org/display/DOCS/findAndModify+Command">findAndModify</a> remove command.</p>
-
-<p>Finds a matching document, removes it, passing the found document (if any) to the callback. Executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndRemove()</code></li>
-</ul>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>rawResult</code>: if true, resolves to the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>A.where().findOneAndRemove(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndRemove(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.where().findOneAndRemove(conditions, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndRemove(conditions) <span class="hljs-comment">// returns Query</span>
-A.where().findOneAndRemove(callback)   <span class="hljs-comment">// executes</span>
-A.where().findOneAndRemove()           <span class="hljs-comment">// returns Query</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndReplace"><a href="#query_Query-findOneAndReplace">Query.prototype.findOneAndReplace()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[replacement]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="http://mongoosejs.com/docs/api.html#query_Query-lean"><code>Query.lean()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a MongoDB <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findOneAndReplace/">findOneAndReplace</a> command.</p>
-
-<p>Finds a matching document, removes it, and passes the found document (if any) to the callback. Executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndReplace()</code></li>
-</ul>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>rawResult</code>: if true, resolves to the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>A.where().findOneAndReplace(filter, replacement, options, callback); <span class="hljs-comment">// executes</span>
-A.where().findOneAndReplace(filter, replacement, options); <span class="hljs-comment">// return Query</span>
-A.where().findOneAndReplace(filter, replacement, callback); <span class="hljs-comment">// executes</span>
-A.where().findOneAndReplace(filter); <span class="hljs-comment">// returns Query</span>
-A.where().findOneAndReplace(callback); <span class="hljs-comment">// executes</span>
-A.where().findOneAndReplace(); <span class="hljs-comment">// returns Query</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndUpdate"><a href="#query_Query-findOneAndUpdate">Query.prototype.findOneAndUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="http://mongoosejs.com/docs/api.html#query_Query-lean"><code>Query.lean()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, doc), <em>unless</em> <code>rawResult</code> is used, in which case params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a mongodb <a href="http://www.mongodb.org/display/DOCS/findAndModify+Command">findAndModify</a> update command.</p>
-
-<p>Finds a matching document, updates it according to the <code>update</code> arg, passing any <code>options</code>, and returns the found document (if any) to the callback. The query executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndUpdate()</code></li>
-</ul>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>new</code>: bool - if true, return the modified document rather than the original. defaults to false (changed in 4.0)</li>
-<li><code>upsert</code>: bool - creates the object if it doesn't exist. defaults to false.</li>
-<li><code>fields</code>: {Object|String} - Field selection. Equivalent to <code>.select(fields).findOneAndUpdate()</code></li>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>context</code> (string) if set to 'query' and <code>runValidators</code> is on, <code>this</code> will refer to the query in custom validator functions that update validation runs. Does nothing if <code>runValidators</code> is false.</li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>query.findOneAndUpdate(conditions, update, options, callback) <span class="hljs-comment">// executes</span>
-query.findOneAndUpdate(conditions, update, options)  <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(conditions, update, callback) <span class="hljs-comment">// executes</span>
-query.findOneAndUpdate(conditions, update)           <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(update, callback)             <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(update)                       <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(callback)                     <span class="hljs-comment">// executes</span>
-query.findOneAndUpdate()                             <span class="hljs-comment">// returns Query</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-geometry"><a href="#query_Query-geometry">Query.prototype.geometry()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">object
-<span class="method-type">&laquo;Object&raquo;</span> Must contain a <code>type</code> property which is a String and a <code>coordinates</code> property which is an Array. See the examples.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$geometry</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> polyA = [[[ <span class="hljs-number">10</span>, <span class="hljs-number">20</span> ], [ <span class="hljs-number">10</span>, <span class="hljs-number">40</span> ], [ <span class="hljs-number">30</span>, <span class="hljs-number">40</span> ], [ <span class="hljs-number">30</span>, <span class="hljs-number">20</span> ]]]
-query.where(<span class="hljs-string">'loc'</span>).within().geometry({ type: <span class="hljs-string">'Polygon'</span>, coordinates: polyA })
-
-<span class="hljs-comment">// or</span>
-<span class="hljs-keyword">var</span> polyB = [[ <span class="hljs-number">0</span>, <span class="hljs-number">0</span> ], [ <span class="hljs-number">1</span>, <span class="hljs-number">1</span> ]]
-query.where(<span class="hljs-string">'loc'</span>).within().geometry({ type: <span class="hljs-string">'LineString'</span>, coordinates: polyB })
-
-<span class="hljs-comment">// or</span>
-<span class="hljs-keyword">var</span> polyC = [ <span class="hljs-number">0</span>, <span class="hljs-number">0</span> ]
-query.where(<span class="hljs-string">'loc'</span>).within().geometry({ type: <span class="hljs-string">'Point'</span>, coordinates: polyC })
-
-<span class="hljs-comment">// or</span>
-query.where(<span class="hljs-string">'loc'</span>).intersects().geometry({ type: <span class="hljs-string">'Point'</span>, coordinates: polyC })</code></pre>
-
-<p>The argument is assigned to the most recent path passed to <code>where()</code>.</p>
-
-<h4>NOTE:</h4>
-
-<p><code>geometry()</code> <strong>must</strong> come after either <code>intersects()</code> or <code>within()</code>.</p>
-
-<p>The <code>object</code> argument must contain <code>type</code> and <code>coordinates</code> properties. - type {String} - coordinates {Array}</p></div><hr class="separate-api-elements"><h3 id="query_Query-getFilter"><a href="#query_Query-getFilter">Query.prototype.getFilter()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> current query filter</li></ul><div><p>Returns the current query filter (also known as conditions) as a POJO.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> Query();
-query.find({ a: <span class="hljs-number">1</span> }).where(<span class="hljs-string">'b'</span>).gt(<span class="hljs-number">2</span>);
-query.getFilter(); <span class="hljs-comment">// { a: 1, b: { $gt: 2 } }</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-getOptions"><a href="#query_Query-getOptions">Query.prototype.getOptions()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the options</li></ul><div><p>Gets query options.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.limit(<span class="hljs-number">10</span>);
-query.setOptions({ maxTimeMS: <span class="hljs-number">1000</span> })
-query.getOptions(); <span class="hljs-comment">// { limit: 10, maxTimeMS: 1000 }</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-getPopulatedPaths"><a href="#query_Query-getPopulatedPaths">Query.prototype.getPopulatedPaths()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> an array of strings representing populated paths</li></ul><div><p>Gets a list of paths to be populated by this query</p>
-
-<h4>Example:</h4>
-
-<pre><code>bookSchema.pre(<span class="hljs-string">'findOne'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-   <span class="hljs-keyword">let</span> keys = <span class="hljs-keyword">this</span>.getPopulatedPaths(); <span class="hljs-comment">// ['author']</span>
- });
- ...
- Book.findOne({}).populate(<span class="hljs-string">'author'</span>);</code></pre>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Deep populate</span>
- <span class="hljs-keyword">const</span> q = L1.find().populate({
-   path: <span class="hljs-string">'level2'</span>,
-   populate: { path: <span class="hljs-string">'level3'</span> }
- });
- q.getPopulatedPaths(); <span class="hljs-comment">// ['level2', 'level2.level3']</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-getQuery"><a href="#query_Query-getQuery">Query.prototype.getQuery()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> current query filter</li></ul><div><p>Returns the current query filter. Equivalent to <code>getFilter()</code>.</p>
-
-<p>You should use <code>getFilter()</code> instead of <code>getQuery()</code> where possible. <code>getQuery()</code> will likely be deprecated in a future release.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.find({ a: <span class="hljs-number">1</span> }).where(<span class="hljs-string">'b'</span>).gt(<span class="hljs-number">2</span>);
-query.getQuery(); <span class="hljs-comment">// { a: 1, b: { $gt: 2 } }</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-getUpdate"><a href="#query_Query-getUpdate">Query.prototype.getUpdate()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> current update operations</li></ul><div><p>Returns the current update operations as a JSON object.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.update({}, { $set: { a: <span class="hljs-number">5</span> } });
-query.getUpdate(); <span class="hljs-comment">// { $set: { a: 5 } }</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-gt"><a href="#query_Query-gt">Query.prototype.gt()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$gt</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>
-
-<h4>Example</h4>
-
-<pre><code>Thing.find().where(<span class="hljs-string">'age'</span>).gt(<span class="hljs-number">21</span>)
-
-<span class="hljs-comment">// or</span>
-Thing.find().gt(<span class="hljs-string">'age'</span>, <span class="hljs-number">21</span>)</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-gte"><a href="#query_Query-gte">Query.prototype.gte()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$gte</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-hint"><a href="#query_Query-hint">Query.prototype.hint()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> a hint object</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets query hints.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.hint({ indexA: <span class="hljs-number">1</span>, indexB: <span class="hljs-number">-1</span>})</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-in"><a href="#query_Query-in">Query.prototype.in()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies an <code>$in</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-intersects"><a href="#query_Query-intersects">Query.prototype.intersects()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[arg]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declares an intersects query for <code>geometry()</code>.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'path'</span>).intersects().geometry({
-    type: <span class="hljs-string">'LineString'</span>
-  , coordinates: [[<span class="hljs-number">180.0</span>, <span class="hljs-number">11.0</span>], [<span class="hljs-number">180</span>, <span class="hljs-number">9.0</span>]]
-})
-
-query.where(<span class="hljs-string">'path'</span>).intersects({
-    type: <span class="hljs-string">'LineString'</span>
-  , coordinates: [[<span class="hljs-number">180.0</span>, <span class="hljs-number">11.0</span>], [<span class="hljs-number">180</span>, <span class="hljs-number">9.0</span>]]
-})</code></pre>
-
-<h4>NOTE:</h4>
-
-<p><strong>MUST</strong> be used after <code>where()</code>.</p>
-
-<h4>NOTE:</h4>
-
-<p>In Mongoose 3.7, <code>intersects</code> changed from a getter to a function. If you need the old syntax, use <a href="https://github.com/ebensing/mongoose-within">this</a>.</p></div><hr class="separate-api-elements"><h3 id="query_Query-j"><a href="#query_Query-j">Query.prototype.j()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Requests acknowledgement that this operation has been persisted to MongoDB's on-disk journal.</p>
-
-<h2>This option is only valid for operations that write to the database</h2>
-
-<ul>
-<li><code>deleteOne()</code></li>
-<li><code>deleteMany()</code></li>
-<li><code>findOneAndDelete()</code></li>
-<li><code>findOneAndReplace()</code></li>
-<li><code>findOneAndUpdate()</code></li>
-<li><code>remove()</code></li>
-<li><code>update()</code></li>
-<li><code>updateOne()</code></li>
-<li><code>updateMany()</code></li>
-</ul>
-
-<p>Defaults to the schema's <a href="/docs/guide.html#writeConcern"><code>writeConcern.j</code> option</a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).deleteOne({ name: <span class="hljs-string">'Ned Stark'</span> }).j(<span class="hljs-literal">true</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-lean"><a href="#query_Query-lean">Query.prototype.lean()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean|Object&raquo;</span> defaults to true</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the lean option.</p>
-
-<p>Documents returned from queries with the <code>lean</code> option enabled are plain javascript objects, not <a href="#document-js">Mongoose Documents</a>. They have no <code>save</code> method, getters/setters, virtuals, or other Mongoose features.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">new</span> Query().lean() <span class="hljs-comment">// true</span>
-<span class="hljs-keyword">new</span> Query().lean(<span class="hljs-literal">true</span>)
-<span class="hljs-keyword">new</span> Query().lean(<span class="hljs-literal">false</span>)
-
-<span class="hljs-keyword">const</span> docs = <span class="hljs-keyword">await</span> Model.find().lean();
-docs[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span></code></pre>
-
-<p><a href="/docs/tutorials/lean.html">Lean is great for high-performance, read-only cases</a>, especially when combined with <a href="/docs/queries.html#streaming">cursors</a>.</p></div><hr class="separate-api-elements"><h3 id="query_Query-limit"><a href="#query_Query-limit">Query.prototype.limit()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the maximum number of documents the query will return.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.limit(<span class="hljs-number">20</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-lt"><a href="#query_Query-lt">Query.prototype.lt()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$lt</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-lte"><a href="#query_Query-lte">Query.prototype.lte()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$lte</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-map"><a href="#query_Query-map">Query.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> function to run to transform the query result</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Runs a function <code>fn</code> and treats the return value of <code>fn</code> as the new value for the query to resolve to.</p>
-
-<p>Any functions you pass to <code>map()</code> will run <strong>after</strong> any post hooks.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> MyModel.findOne().map(res =&gt; {
-  <span class="hljs-comment">// Sets a `loadedAt` property on the doc that tells you the time the</span>
-  <span class="hljs-comment">// document was loaded.</span>
-  <span class="hljs-keyword">return</span> res == <span class="hljs-literal">null</span> ?
-    res :
-    <span class="hljs-built_in">Object</span>.assign(res, { loadedAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>() });
-});</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-maxDistance"><a href="#query_Query-maxDistance">Query.prototype.maxDistance()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>maxDistance</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-maxScan"><a href="#query_Query-maxScan">Query.prototype.maxScan()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the maxScan option.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.maxScan(<span class="hljs-number">100</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-maxTimeMS"><a href="#query_Query-maxTimeMS">Query.prototype.maxTimeMS()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[ms]
-<span class="method-type">&laquo;Number&raquo;</span> The number of milliseconds</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the <a href="https://docs.mongodb.com/manual/reference/method/cursor.maxTimeMS/">maxTimeMS</a> option. This will tell the MongoDB server to abort if the query or write op has been running for more than <code>ms</code> milliseconds.</p>
-
-<p>Calling <code>query.maxTimeMS(v)</code> is equivalent to <code>query.setOption({ maxTimeMS: v })</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> Query();
-<span class="hljs-comment">// Throws an error 'operation exceeded time limit' as long as there's</span>
-<span class="hljs-comment">// &gt;= 1 doc in the queried collection</span>
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> query.find({ $where: <span class="hljs-string">'sleep(1000) || true'</span> }).maxTimeMS(<span class="hljs-number">100</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-maxscan"><a href="#query_Query-maxscan">Query.prototype.maxscan()</a></h3><div><p><em>DEPRECATED</em> Alias of <code>maxScan</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-merge"><a href="#query_Query-merge">Query.prototype.merge()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">source
-<span class="method-type">&laquo;Query|Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Merges another Query or conditions object into this one.</p>
-
-<p>When a Query is passed, conditions, field selection and options are merged.</p></div><hr class="separate-api-elements"><h3 id="query_Query-mod"><a href="#query_Query-mod">Query.prototype.mod()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Array&raquo;</span> must be of length 2, first element is <code>divisor</code>, 2nd element is <code>remainder</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$mod</code> condition, filters documents for documents whose <code>path</code> property is a number that is equal to <code>remainder</code> modulo <code>divisor</code>.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// All find products whose inventory is odd</span>
-Product.find().mod(<span class="hljs-string">'inventory'</span>, [<span class="hljs-number">2</span>, <span class="hljs-number">1</span>]);
-Product.find().where(<span class="hljs-string">'inventory'</span>).mod([<span class="hljs-number">2</span>, <span class="hljs-number">1</span>]);
-<span class="hljs-comment">// This syntax is a little strange, but supported.</span>
-Product.find().where(<span class="hljs-string">'inventory'</span>).mod(<span class="hljs-number">2</span>, <span class="hljs-number">1</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-mongooseOptions"><a href="#query_Query-mongooseOptions">Query.prototype.mongooseOptions()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> if specified, overwrites the current options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the options</li></ul><div><p>Getter/setter around the current mongoose-specific options for this query Below are the current Mongoose-specific options.</p>
-
-<ul>
-<li><code>populate</code>: an array representing what paths will be populated. Should have one entry for each call to <a href="/docs/api.html#query_Query-populate"><code>Query.prototype.populate()</code></a></li>
-<li><code>lean</code>: if truthy, Mongoose will not <a href="/docs/api.html#model_Model.hydrate">hydrate</a> any documents that are returned from this query. See <a href="/docs/api.html#query_Query-lean"><code>Query.prototype.lean()</code></a> for more information.</li>
-<li><code>strict</code>: controls how Mongoose handles keys that aren't in the schema for updates. This option is <code>true</code> by default, which means Mongoose will silently strip any paths in the update that aren't in the schema. See the <a href="/docs/guide.html#strict"><code>strict</code> mode docs</a> for more information.</li>
-<li><code>strictQuery</code>: controls how Mongoose handles keys that aren't in the schema for the query <code>filter</code>. This option is <code>false</code> by default for backwards compatibility, which means Mongoose will allow <code>Model.find({ foo: 'bar' })</code> even if <code>foo</code> is not in the schema. See the <a href="/docs/guide.html#strictQuery"><code>strictQuery</code> docs</a> for more information.</li>
-<li><code>useFindAndModify</code>: used to work around the <a href="/docs/deprecations.html#-findandmodify-"><code>findAndModify()</code> deprecation warning</a></li>
-<li><code>omitUndefined</code>: delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: 'bar', baz: undefined })</code> before sending the update to the server.</li>
-<li><code>nearSphere</code>: use <code>$nearSphere</code> instead of <code>near()</code>. See the <a href="/docs/api.html#query_Query-nearSphere"><code>Query.prototype.nearSphere()</code> docs</a></li>
-</ul>
-
-<p>Mongoose maintains a separate object for internal options because Mongoose sends <code>Query.prototype.options</code> to the MongoDB server, and the above options are not relevant for the MongoDB server.</p></div><hr class="separate-api-elements"><h3 id="query_Query-ne"><a href="#query_Query-ne">Query.prototype.ne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$ne</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-near"><a href="#query_Query-near">Query.prototype.near()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$near</code> or <code>$nearSphere</code> condition</p>
-
-<p>These operators return documents sorted by distance.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>] });
-query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> });
-query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span>, spherical: <span class="hljs-literal">true</span> });
-query.near(<span class="hljs-string">'loc'</span>, { center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-nearSphere"><a href="#query_Query-nearSphere">Query.prototype.nearSphere()</a></h3><div><p><em>DEPRECATED</em> Specifies a <code>$nearSphere</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).nearSphere({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> });</code></pre>
-
-<p><strong>Deprecated.</strong> Use <code>query.near()</code> instead with the <code>spherical</code> option set to <code>true</code>.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], spherical: <span class="hljs-literal">true</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-nin"><a href="#query_Query-nin">Query.prototype.nin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies an <code>$nin</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-nor"><a href="#query_Query-nor">Query.prototype.nor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">array
-<span class="method-type">&laquo;Array&raquo;</span> array of conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies arguments for a <code>$nor</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.nor([{ color: <span class="hljs-string">'green'</span> }, { status: <span class="hljs-string">'ok'</span> }])</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-or"><a href="#query_Query-or">Query.prototype.or()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">array
-<span class="method-type">&laquo;Array&raquo;</span> array of conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies arguments for an <code>$or</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.or([{ color: <span class="hljs-string">'red'</span> }, { status: <span class="hljs-string">'emergency'</span> }])</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-orFail"><a href="#query_Query-orFail">Query.prototype.orFail()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[err]
-<span class="method-type">&laquo;Function|Error&raquo;</span> optional error to throw if no docs match <code>filter</code>. If not specified, <code>orFail()</code> will throw a <code>DocumentNotFoundError</code></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Make this query throw an error if no documents match the given <code>filter</code>. This is handy for integrating with async/await, because <code>orFail()</code> saves you an extra <code>if</code> statement to check if no document was found.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Throws if no doc returned</span>
-<span class="hljs-keyword">await</span> Model.findOne({ foo: <span class="hljs-string">'bar'</span> }).orFail();
-
-<span class="hljs-comment">// Throws if no document was updated</span>
-<span class="hljs-keyword">await</span> Model.updateOne({ foo: <span class="hljs-string">'bar'</span> }, { name: <span class="hljs-string">'test'</span> }).orFail();
-
-<span class="hljs-comment">// Throws "No docs found!" error if no docs match `{ foo: 'bar' }`</span>
-<span class="hljs-keyword">await</span> Model.find({ foo: <span class="hljs-string">'bar'</span> }).orFail(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'No docs found!'</span>));
-
-<span class="hljs-comment">// Throws "Not found" error if no document was found</span>
-<span class="hljs-keyword">await</span> Model.findOneAndUpdate({ foo: <span class="hljs-string">'bar'</span> }, { name: <span class="hljs-string">'test'</span> }).
-  orFail(() =&gt; <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Not found'</span>));</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-polygon"><a href="#query_Query-polygon">Query.prototype.polygon()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String|Array&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[coordinatePairs...]
-<span class="method-type">&laquo;Array|Object&raquo;</span> </li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$polygon</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).within().polygon([<span class="hljs-number">10</span>,<span class="hljs-number">20</span>], [<span class="hljs-number">13</span>, <span class="hljs-number">25</span>], [<span class="hljs-number">7</span>,<span class="hljs-number">15</span>])
-query.polygon(<span class="hljs-string">'loc'</span>, [<span class="hljs-number">10</span>,<span class="hljs-number">20</span>], [<span class="hljs-number">13</span>, <span class="hljs-number">25</span>], [<span class="hljs-number">7</span>,<span class="hljs-number">15</span>])</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-populate"><a href="#query_Query-populate">Query.prototype.populate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;Object|String&raquo;</span> either the path to populate or an object specifying all parameters</li><li class="param">[select]
-<span class="method-type">&laquo;Object|String&raquo;</span> Field selection for the population query</li><li class="param">[model]
-<span class="method-type">&laquo;Model&raquo;</span> The model you wish to use for population. If not specified, populate will look up the model by the name in the Schema&#39;s <code>ref</code> field.</li><li class="param">[match]
-<span class="method-type">&laquo;Object&raquo;</span> Conditions for the population query</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Options for the population query (sort, etc)</li><ul style="margin-top: 0.5em"><li>[options.path=null]
-<span class="method-type">&laquo;String&raquo;</span> The path to populate.</li></ul><ul style="margin-top: 0.5em"><li>[options.retainNullValues=false]
-<span class="method-type">&laquo;boolean&raquo;</span> by default, Mongoose removes null and undefined values from populated arrays. Use this option to make <code>populate()</code> retain <code>null</code> and <code>undefined</code> array entries.</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if true, Mongoose will call any getters defined on the <code>localField</code>. By default, Mongoose gets the raw value of <code>localField</code>. For example, you would need to set this option to <code>true</code> if you wanted to <a href="/docs/schematypes.html#schematype-options">add a <code>lowercase</code> getter to your <code>localField</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.clone=false]
-<span class="method-type">&laquo;boolean&raquo;</span> When you do <code>BlogPost.find().populate(&#39;author&#39;)</code>, blog posts with the same author will share 1 copy of an <code>author</code> doc. Enable this option to make Mongoose clone populated docs before assigning them.</li></ul><ul style="margin-top: 0.5em"><li>[options.match=null]
-<span class="method-type">&laquo;Object|Function&raquo;</span> Add an additional filter to the populate query. Can be a filter object containing <a href="https://docs.mongodb.com/manual/tutorial/query-documents/">MongoDB query syntax</a>, or a function that returns a filter object.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies paths which should be populated with other documents.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Kitten.findOne().populate(<span class="hljs-string">'owner'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kitten</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(kitten.owner.name) <span class="hljs-comment">// Max</span>
-})
-
-Kitten.find().populate({
-  path: <span class="hljs-string">'owner'</span>,
-  select: <span class="hljs-string">'name'</span>,
-  match: { color: <span class="hljs-string">'black'</span> },
-  options: { sort: { name: <span class="hljs-number">-1</span> } }
-}).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kittens</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(kittens[<span class="hljs-number">0</span>].owner.name) <span class="hljs-comment">// Zoopa</span>
-})
-
-<span class="hljs-comment">// alternatively</span>
-Kitten.find().populate(<span class="hljs-string">'owner'</span>, <span class="hljs-string">'name'</span>, <span class="hljs-literal">null</span>, {sort: { name: <span class="hljs-number">-1</span> }}).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kittens</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(kittens[<span class="hljs-number">0</span>].owner.name) <span class="hljs-comment">// Zoopa</span>
-})</code></pre>
-
-<p>Paths are populated after the query executes and a response is received. A separate query is then executed for each path specified for population. After a response for each query has also been returned, the results are passed to the callback.</p></div><hr class="separate-api-elements"><h3 id="query_Query-projection"><a href="#query_Query-projection">Query.prototype.projection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|null&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the current projection</li></ul><div><p>Get/set the current projection (AKA fields). Pass <code>null</code> to remove the current projection.</p>
-
-<p>Unlike <code>projection()</code>, the <code>select()</code> function modifies the current projection in place. This function overwrites the existing projection.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> q = Model.find();
-q.projection(); <span class="hljs-comment">// null</span>
-
-q.select(<span class="hljs-string">'a b'</span>);
-q.projection(); <span class="hljs-comment">// { a: 1, b: 1 }</span>
-
-q.projection({ c: <span class="hljs-number">1</span> });
-q.projection(); <span class="hljs-comment">// { c: 1 }</span>
-
-q.projection(<span class="hljs-literal">null</span>);
-q.projection(); <span class="hljs-comment">// null</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-read"><a href="#query_Query-read">Query.prototype.read()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">pref
-<span class="method-type">&laquo;String&raquo;</span> one of the listed preference options or aliases</li><li class="param">[tags]
-<span class="method-type">&laquo;Array&raquo;</span> optional tags for this query</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Determines the MongoDB nodes from which to read.</p>
-
-<h4>Preferences:</h4>
-
-<pre><code>primary - (<span class="hljs-keyword">default</span>) Read <span class="hljs-keyword">from</span> primary only. Operations will produce an error <span class="hljs-keyword">if</span> primary is unavailable. Cannot be combined <span class="hljs-keyword">with</span> tags.
-secondary            Read <span class="hljs-keyword">from</span> secondary <span class="hljs-keyword">if</span> available, otherwise error.
-primaryPreferred     Read <span class="hljs-keyword">from</span> primary <span class="hljs-keyword">if</span> available, otherwise a secondary.
-secondaryPreferred   Read <span class="hljs-keyword">from</span> a secondary <span class="hljs-keyword">if</span> available, otherwise read <span class="hljs-keyword">from</span> the primary.
-nearest              All operations read <span class="hljs-keyword">from</span> among the nearest candidates, but unlike other modes, <span class="hljs-keyword">this</span> option will include both the primary and all secondaries <span class="hljs-keyword">in</span> the random selection.</code></pre>
-
-<p>Aliases</p>
-
-<pre><code>p   primary
-pp  primaryPreferred
-s   secondary
-sp  secondaryPreferred
-n   nearest</code></pre>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'primary'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'p'</span>)  <span class="hljs-comment">// same as primary</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'primaryPreferred'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'pp'</span>) <span class="hljs-comment">// same as primaryPreferred</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'secondary'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'s'</span>)  <span class="hljs-comment">// same as secondary</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'secondaryPreferred'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'sp'</span>) <span class="hljs-comment">// same as secondaryPreferred</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'nearest'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'n'</span>)  <span class="hljs-comment">// same as nearest</span>
-
-<span class="hljs-comment">// read from secondaries with matching tags</span>
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'s'</span>, [{ dc:<span class="hljs-string">'sf'</span>, s: <span class="hljs-number">1</span> },{ dc:<span class="hljs-string">'ma'</span>, s: <span class="hljs-number">2</span> }])</code></pre>
-
-<p>Read more about how to use read preferrences <a href="http://docs.mongodb.org/manual/applications/replication/#read-preference">here</a> and <a href="http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences">here</a>.</p></div><hr class="separate-api-elements"><h3 id="query_Query-readConcern"><a href="#query_Query-readConcern">Query.prototype.readConcern()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">level
-<span class="method-type">&laquo;String&raquo;</span> one of the listed read concern level or their aliases</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the readConcern option for the query.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'local'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'l'</span>)  <span class="hljs-comment">// same as local</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'available'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'a'</span>)  <span class="hljs-comment">// same as available</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'majority'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'m'</span>)  <span class="hljs-comment">// same as majority</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'linearizable'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'lz'</span>) <span class="hljs-comment">// same as linearizable</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'snapshot'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'s'</span>)  <span class="hljs-comment">// same as snapshot</span></code></pre>
-
-<h4>Read Concern Level:</h4>
-
-<pre><code>local         MongoDB <span class="hljs-number">3.2</span>+ The query returns <span class="hljs-keyword">from</span> the instance <span class="hljs-keyword">with</span> no guarantee guarantee that the data has been written to a majority <span class="hljs-keyword">of</span> the replica set members (i.e. may be rolled back).
-available     MongoDB <span class="hljs-number">3.6</span>+ The query returns <span class="hljs-keyword">from</span> the instance <span class="hljs-keyword">with</span> no guarantee guarantee that the data has been written to a majority <span class="hljs-keyword">of</span> the replica set members (i.e. may be rolled back).
-majority      MongoDB <span class="hljs-number">3.2</span>+ The query returns the data that has been acknowledged by a majority <span class="hljs-keyword">of</span> the replica set members. The documents returned by the read operation are durable, even <span class="hljs-keyword">in</span> the event <span class="hljs-keyword">of</span> failure.
-linearizable  MongoDB <span class="hljs-number">3.4</span>+ The query returns data that reflects all successful majority-acknowledged writes that completed prior to the start <span class="hljs-keyword">of</span> the read operation. The query may wait <span class="hljs-keyword">for</span> concurrently executing writes to propagate to a majority <span class="hljs-keyword">of</span> replica set members before returning results.
-snapshot      MongoDB <span class="hljs-number">4.0</span>+ Only available <span class="hljs-keyword">for</span> operations within multi-<span class="hljs-built_in">document</span> transactions. Upon transaction commit <span class="hljs-keyword">with</span> write concern <span class="hljs-string">"majority"</span>, the transaction operations are guaranteed to have read <span class="hljs-keyword">from</span> a snapshot <span class="hljs-keyword">of</span> majority-committed data.</code></pre>
-
-<p>Aliases</p>
-
-<pre><code>l   local
-a   available
-m   majority
-lz  linearizable
-s   snapshot</code></pre>
-
-<p>Read more about how to use read concern <a href="https://docs.mongodb.com/manual/reference/read-concern/">here</a>.</p></div><hr class="separate-api-elements"><h3 id="query_Query-regex"><a href="#query_Query-regex">Query.prototype.regex()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;String|RegExp&raquo;</span> </li></ul><div><p>Specifies a <code>$regex</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p></div><hr class="separate-api-elements"><h3 id="query_Query-remove"><a href="#query_Query-remove">Query.prototype.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, mongooseDeleteResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a remove() operation. <code>remove()</code> is deprecated, you should use <a href="#query_Query-deleteOne"><code>deleteOne()</code></a> or <a href="#query_Query-deleteMany"><code>deleteMany()</code></a> instead.</p>
-
-<p>This function does not trigger any middleware</p>
-
-<h4>Example</h4>
-
-<pre><code>Character.remove({ name: <span class="hljs-regexp">/Stark/</span> }, callback);</code></pre>
-
-<p>This function calls the MongoDB driver's <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove"><code>Collection#remove()</code> function</a>. The returned <a href="https://mongoosejs.com/docs/queries.html">promise</a> resolves to an object that contains 3 properties:</p>
-
-<ul>
-<li><code>ok</code>: <code>1</code> if no errors occurred</li>
-<li><code>deletedCount</code>: the number of documents deleted</li>
-<li><code>n</code>: the number of documents deleted. Equal to <code>deletedCount</code>.</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.remove({ name: <span class="hljs-regexp">/Stark/</span> });
-<span class="hljs-comment">// Number of docs deleted</span>
-res.deletedCount;</code></pre>
-
-<h4>Note</h4>
-
-<p>Calling <code>remove()</code> creates a <a href="./queries.html">Mongoose query</a>, and a query does not execute until you either pass a callback, call <a href="#query_Query-then"><code>Query#then()</code></a>, or call <a href="#query_Query-exec"><code>Query#exec()</code></a>.</p>
-
-<pre><code><span class="hljs-comment">// not executed</span>
-<span class="hljs-keyword">const</span> query = Character.remove({ name: <span class="hljs-regexp">/Stark/</span> });
-
-<span class="hljs-comment">// executed</span>
-Character.remove({ name: <span class="hljs-regexp">/Stark/</span> }, callback);
-Character.remove({ name: <span class="hljs-regexp">/Stark/</span> }).remove(callback);
-
-<span class="hljs-comment">// executed without a callback</span>
-Character.exec();</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-replaceOne"><a href="#query_Query-replaceOne">Query.prototype.replaceOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a replaceOne() operation. Same as <code>update()</code>, except MongoDB will replace the existing document and will not accept any <a href="https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern">atomic</a> operators (<code>$set</code>, etc.)</p>
-
-<p><strong>Note</strong> replaceOne will <em>not</em> fire update middleware. Use <code>pre('replaceOne')</code> and <code>post('replaceOne')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.replaceOne({ _id: <span class="hljs-number">24601</span> }, { name: <span class="hljs-string">'Jean Valjean'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>replaceOne()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="query_Query-select"><a href="#query_Query-select">Query.prototype.select()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies which document fields to include or exclude (also known as the query "projection")</p>
-
-<p>When using string syntax, prefixing a path with <code>-</code> will flag that path as excluded. When a path does not have the <code>-</code> prefix, it is included. Lastly, if a path is prefixed with <code>+</code>, it forces inclusion of the path, which is useful for paths excluded at the <a href="/docs/api.html#schematype_SchemaType-select">schema level</a>.</p>
-
-<p>A projection <em>must</em> be either inclusive or exclusive. In other words, you must either list the fields to include (which excludes all others), or list the fields to exclude (which implies all other fields are included). The <a href="https://docs.mongodb.com/manual/tutorial/project-fields-from-query-results/#suppress-id-field"><code>_id</code> field is the only exception because MongoDB includes it by default</a>.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// include a and b, exclude other fields</span>
-query.select(<span class="hljs-string">'a b'</span>);
-
-<span class="hljs-comment">// exclude c and d, include other fields</span>
-query.select(<span class="hljs-string">'-c -d'</span>);
-
-<span class="hljs-comment">// Use `+` to override schema-level `select: false` without making the</span>
-<span class="hljs-comment">// projection inclusive.</span>
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  foo: { type: <span class="hljs-built_in">String</span>, select: <span class="hljs-literal">false</span> },
-  bar: <span class="hljs-built_in">String</span>
-});
-<span class="hljs-comment">// ...</span>
-query.select(<span class="hljs-string">'+foo'</span>); <span class="hljs-comment">// Override foo's `select: false` without excluding `bar`</span>
-
-<span class="hljs-comment">// or you may use object notation, useful when</span>
-<span class="hljs-comment">// you have keys already prefixed with a "-"</span>
-query.select({ a: <span class="hljs-number">1</span>, b: <span class="hljs-number">1</span> });
-query.select({ c: <span class="hljs-number">0</span>, d: <span class="hljs-number">0</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-selected"><a href="#query_Query-selected">Query.prototype.selected()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Determines if field selection has been made.</p></div><hr class="separate-api-elements"><h3 id="query_Query-selectedExclusively"><a href="#query_Query-selectedExclusively">Query.prototype.selectedExclusively()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Determines if exclusive field selection has been made.</p>
-
-<pre><code>query.selectedExclusively() <span class="hljs-comment">// false</span>
-query.select(<span class="hljs-string">'-name'</span>)
-query.selectedExclusively() <span class="hljs-comment">// true</span>
-query.selectedInclusively() <span class="hljs-comment">// false</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-selectedInclusively"><a href="#query_Query-selectedInclusively">Query.prototype.selectedInclusively()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Determines if inclusive field selection has been made.</p>
-
-<pre><code>query.selectedInclusively() <span class="hljs-comment">// false</span>
-query.select(<span class="hljs-string">'name'</span>)
-query.selectedInclusively() <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-session"><a href="#query_Query-session">Query.prototype.session()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[session]
-<span class="method-type">&laquo;ClientSession&raquo;</span> from <code>await conn.startSession()</code></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the <a href="https://docs.mongodb.com/manual/reference/server-sessions/">MongoDB session</a> associated with this query. Sessions are how you mark a query as part of a <a href="/docs/transactions.html">transaction</a>.</p>
-
-<p>Calling <code>session(null)</code> removes the session from this query.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">await</span> mongoose.startSession();
-<span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).findOne({ name: <span class="hljs-string">'Axl Rose'</span> }).session(s);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-set"><a href="#query_Query-set">Query.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object&raquo;</span> path or object of key/value pairs to set</li><li class="param">[val]
-<span class="method-type">&laquo;Any&raquo;</span> the value to set</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Adds a <code>$set</code> to this query's update without changing the operation. This is useful for query middleware so you can add an update regardless of whether you use <code>updateOne()</code>, <code>updateMany()</code>, <code>findOneAndUpdate()</code>, etc.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Updates `{ $set: { updatedAt: new Date() } }`</span>
-<span class="hljs-keyword">new</span> Query().updateOne({}, {}).set(<span class="hljs-string">'updatedAt'</span>, <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>());
-<span class="hljs-keyword">new</span> Query().updateMany({}, {}).set({ updatedAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>() });</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-setOptions"><a href="#query_Query-setOptions">Query.prototype.setOptions()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets query options. Some options only make sense for certain operations.</p>
-
-<h4>Options:</h4>
-
-<p>The following options are only for <code>find()</code>:</p>
-
-<ul>
-<li><a href="http://www.mongodb.org/display/DOCS/Tailable+Cursors">tailable</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsort()%7D%7D">sort</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Blimit%28%29%7D%7D">limit</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bskip%28%29%7D%7D">skip</a></li>
-<li><a href="https://docs.mongodb.org/v3.2/reference/operator/meta/maxScan/#metaOp._S_maxScan">maxscan</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7BbatchSize%28%29%7D%7D">batchSize</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24comment">comment</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsnapshot%28%29%7D%7D">snapshot</a></li>
-<li><a href="http://docs.mongodb.org/manual/applications/replication/#read-preference">readPreference</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24hint">hint</a></li>
-</ul>
-
-<p>The following options are only for write operations: <code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>, <code>replaceOne()</code>, <code>findOneAndUpdate()</code>, and <code>findByIdAndUpdate()</code>:</p>
-
-<ul>
-<li><a href="https://docs.mongodb.com/manual/reference/method/db.collection.update/">upsert</a></li>
-<li><a href="https://docs.mongodb.com/manual/reference/method/db.collection.update/">writeConcern</a></li>
-<li><a href="https://mongoosejs.com/docs/guide.html#timestamps">timestamps</a>: If <code>timestamps</code> is set in the schema, set this option to <code>false</code> to skip timestamps for that particular update. Has no effect if <code>timestamps</code> is not enabled in the schema options.</li>
-<li>omitUndefined: delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: 'bar', baz: undefined })</code> before sending the update to the server.</li>
-</ul>
-
-<p>The following options are only for <code>find()</code>, <code>findOne()</code>, <code>findById()</code>, <code>findOneAndUpdate()</code>, and <code>findByIdAndUpdate()</code>:</p>
-
-<ul>
-<li><a href="./api.html#query_Query-lean">lean</a></li>
-</ul>
-
-<p>The following options are only for all operations <strong>except</strong> <code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>, <code>remove()</code>, <code>deleteOne()</code>, and <code>deleteMany()</code>:</p>
-
-<ul>
-<li><a href="https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/">maxTimeMS</a></li>
-</ul>
-
-<h2>The following options are for all operations</h2>
-
-<ul>
-<li><a href="https://docs.mongodb.com/manual/reference/collation/">collation</a></li>
-<li><a href="https://docs.mongodb.com/manual/reference/server-sessions/">session</a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="query_Query-setQuery"><a href="#query_Query-setQuery">Query.prototype.setQuery()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">new
-<span class="method-type">&laquo;Object&raquo;</span> query conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;undefined&raquo;</span> </li></ul><div><p>Sets the query conditions to the provided JSON object.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.find({ a: <span class="hljs-number">1</span> })
-query.setQuery({ a: <span class="hljs-number">2</span> });
-query.getQuery(); <span class="hljs-comment">// { a: 2 }</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-setUpdate"><a href="#query_Query-setUpdate">Query.prototype.setUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">new
-<span class="method-type">&laquo;Object&raquo;</span> update operation</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;undefined&raquo;</span> </li></ul><div><p>Sets the current update operation to new value.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.update({}, { $set: { a: <span class="hljs-number">5</span> } });
-query.setUpdate({ $set: { b: <span class="hljs-number">6</span> } });
-query.getUpdate(); <span class="hljs-comment">// { $set: { b: 6 } }</span></code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-size"><a href="#query_Query-size">Query.prototype.size()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$size</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>
-
-<h4>Example</h4>
-
-<pre><code>MyModel.where(<span class="hljs-string">'tags'</span>).size(<span class="hljs-number">0</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-
-  assert(<span class="hljs-built_in">Array</span>.isArray(docs));
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'documents with 0 tags'</span>, docs);
-})</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-skip"><a href="#query_Query-skip">Query.prototype.skip()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the number of documents to skip.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.skip(<span class="hljs-number">100</span>).limit(<span class="hljs-number">20</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-slaveOk"><a href="#query_Query-slaveOk">Query.prototype.slaveOk()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">v
-<span class="method-type">&laquo;Boolean&raquo;</span> defaults to true</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p><em>DEPRECATED</em> Sets the slaveOk option.</p>
-
-<p><strong>Deprecated</strong> in MongoDB 2.2 in favor of <a href="#query_Query-read">read preferences</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>query.slaveOk() <span class="hljs-comment">// true</span>
-query.slaveOk(<span class="hljs-literal">true</span>)
-query.slaveOk(<span class="hljs-literal">false</span>)</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-slice"><a href="#query_Query-slice">Query.prototype.slice()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> number/range of elements to slice</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$slice</code> projection for an array.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.slice(<span class="hljs-string">'comments'</span>, <span class="hljs-number">5</span>)
-query.slice(<span class="hljs-string">'comments'</span>, <span class="hljs-number">-5</span>)
-query.slice(<span class="hljs-string">'comments'</span>, [<span class="hljs-number">10</span>, <span class="hljs-number">5</span>])
-query.where(<span class="hljs-string">'comments'</span>).slice(<span class="hljs-number">5</span>)
-query.where(<span class="hljs-string">'comments'</span>).slice([<span class="hljs-number">-10</span>, <span class="hljs-number">5</span>])</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-snapshot"><a href="#query_Query-snapshot">Query.prototype.snapshot()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>snapshot</code> query.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.snapshot() <span class="hljs-comment">// true</span>
-query.snapshot(<span class="hljs-literal">true</span>)
-query.snapshot(<span class="hljs-literal">false</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-sort"><a href="#query_Query-sort">Query.prototype.sort()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the sort order</p>
-
-<p>If an object is passed, values allowed are <code>asc</code>, <code>desc</code>, <code>ascending</code>, <code>descending</code>, <code>1</code>, and <code>-1</code>.</p>
-
-<p>If a string is passed, it must be a space delimited list of path names. The sort order of each path is ascending unless the path name is prefixed with <code>-</code> which will be treated as descending.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// sort by "field" ascending and "test" descending</span>
-query.sort({ field: <span class="hljs-string">'asc'</span>, test: <span class="hljs-number">-1</span> });
-
-<span class="hljs-comment">// equivalent</span>
-query.sort(<span class="hljs-string">'field -test'</span>);</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-tailable"><a href="#query_Query-tailable">Query.prototype.tailable()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> defaults to true</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> options to set</li><ul style="margin-top: 0.5em"><li>[opts.numberOfRetries]
-<span class="method-type">&laquo;Number&raquo;</span> if cursor is exhausted, retry this many times before giving up</li></ul><ul style="margin-top: 0.5em"><li>[opts.tailableRetryInterval]
-<span class="method-type">&laquo;Number&raquo;</span> if cursor is exhausted, wait this many milliseconds before retrying</li></ul></ul><div><p>Sets the tailable option (for use with capped collections).</p>
-
-<h4>Example</h4>
-
-<pre><code>query.tailable() <span class="hljs-comment">// true</span>
-query.tailable(<span class="hljs-literal">true</span>)
-query.tailable(<span class="hljs-literal">false</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p></div><hr class="separate-api-elements"><h3 id="query_Query-then"><a href="#query_Query-then">Query.prototype.then()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[resolve]
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query returning a <code>Promise</code> which will be resolved with either the doc(s) or rejected with the error.</p></div><hr class="separate-api-elements"><h3 id="query_Query-toConstructor"><a href="#query_Query-toConstructor">Query.prototype.toConstructor()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> subclass-of-Query</li></ul><div><p>Converts this query to a customized, reusable query constructor with all arguments and options retained.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Create a query for adventure movies and read from the primary</span>
-<span class="hljs-comment">// node in the replica-set unless it is down, in which case we'll</span>
-<span class="hljs-comment">// read from a secondary node.</span>
-<span class="hljs-keyword">var</span> query = Movie.find({ tags: <span class="hljs-string">'adventure'</span> }).read(<span class="hljs-string">'primaryPreferred'</span>);
-
-<span class="hljs-comment">// create a custom Query constructor based off these settings</span>
-<span class="hljs-keyword">var</span> Adventure = query.toConstructor();
-
-<span class="hljs-comment">// Adventure is now a subclass of mongoose.Query and works the same way but with the</span>
-<span class="hljs-comment">// default query parameters and options set.</span>
-Adventure().exec(callback)
-
-<span class="hljs-comment">// further narrow down our query results while still using the previous settings</span>
-Adventure().where({ name: <span class="hljs-regexp">/^Life/</span> }).exec(callback);
-
-<span class="hljs-comment">// since Adventure is a stand-alone constructor we can also add our own</span>
-<span class="hljs-comment">// helper methods and getters without impacting global queries</span>
-Adventure.prototype.startsWith = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">prefix</span>) </span>{
-  <span class="hljs-keyword">this</span>.where({ name: <span class="hljs-keyword">new</span> <span class="hljs-built_in">RegExp</span>(<span class="hljs-string">'^'</span> + prefix) })
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>;
-}
-<span class="hljs-built_in">Object</span>.defineProperty(Adventure.prototype, <span class="hljs-string">'highlyRated'</span>, {
-  get: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-    <span class="hljs-keyword">this</span>.where({ rating: { $gt: <span class="hljs-number">4.5</span> }});
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>;
-  }
-})
-Adventure().highlyRated.startsWith(<span class="hljs-string">'Life'</span>).exec(callback)</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-update"><a href="#query_Query-update">Query.prototype.update()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as an update() operation.</p>
-
-<p><em>All paths passed that are not <a href="https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern">atomic</a> operations will become <code>$set</code> ops.</em></p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>update()</code></li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code>Model.where({ _id: id }).update({ title: <span class="hljs-string">'words'</span> })
-
-<span class="hljs-comment">// becomes</span>
-
-Model.where({ _id: id }).update({ $set: { title: <span class="hljs-string">'words'</span> }})</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li><code>upsert</code> (boolean) whether to create the doc if it doesn't match (false)</li>
-<li><code>multi</code> (boolean) whether multiple documents should be updated (false)</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>strict</code> (boolean) overrides the <code>strict</code> option for this update</li>
-<li><code>overwrite</code> (boolean) disables update-only mode, allowing you to overwrite the doc (false)</li>
-<li><code>context</code> (string) if set to 'query' and <code>runValidators</code> is on, <code>this</code> will refer to the query in custom validator functions that update validation runs. Does nothing if <code>runValidators</code> is false.</li>
-<li><code>read</code></li>
-<li><code>writeConcern</code></li>
-</ul>
-
-<h4>Note</h4>
-
-<p>Passing an empty object <code>{}</code> as the doc will result in a no-op unless the <code>overwrite</code> option is passed. Without the <code>overwrite</code> option set, the update operation will be ignored and the callback executed without sending the command to MongoDB so as to prevent accidently overwritting documents in the collection.</p>
-
-<h4>Note</h4>
-
-<p>The operation is only executed when a callback is passed. To force execution without a callback, we must first call update() and then execute it by using the <code>exec()</code> method.</p>
-
-<pre><code>var q = Model.where({ _id: id });
-q.update({ $set: { name: 'bob' }}).update(); // not executed
-
-q.update({ $set: { name: 'bob' }}).exec(); // executed
-
-// keys that are not [atomic](<a href='https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern'>https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern</a>) ops become `$set`.
-// this executes the same command as the previous example.
-q.update({ name: 'bob' }).exec();
-
-// overwriting with empty docs
-var q = Model.where({ _id: id }).setOptions({ overwrite: true })
-q.update({ }, callback); // executes
-
-// multi update with overwrite to empty doc
-var q = Model.where({ _id: id });
-q.setOptions({ multi: true, overwrite: true })
-q.update({ });
-q.update(callback); // executed
-
-// multi updates
-Model.where()
-     .update({ name: /^match/ }, { $set: { arr: [] }}, { multi: true }, callback)
-
-// more multi updates
-Model.where()
-     .setOptions({ multi: true })
-     .update({ $set: { arr: [] }}, callback)
-
-// single update by default
-Model.where({ email: '<a href='mailto:address@example.com'>address@example.com</a>' })
-     .update({ $inc: { counter: 1 }}, callback)
-</code></pre>
-
-<p>API summary</p>
-
-<pre><code>update(filter, doc, options, cb) <span class="hljs-comment">// executes</span>
-update(filter, doc, options)
-update(filter, doc, cb) <span class="hljs-comment">// executes</span>
-update(filter, doc)
-update(doc, cb) <span class="hljs-comment">// executes</span>
-update(doc)
-update(cb) <span class="hljs-comment">// executes</span>
-update(<span class="hljs-literal">true</span>) <span class="hljs-comment">// executes</span>
-update()</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-updateMany"><a href="#query_Query-updateMany">Query.prototype.updateMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as an updateMany() operation. Same as <code>update()</code>, except MongoDB will update <em>all</em> documents that match <code>filter</code> (as opposed to just the first one) regardless of the value of the <code>multi</code> option.</p>
-
-<p><strong>Note</strong> updateMany will <em>not</em> fire update middleware. Use <code>pre('updateMany')</code> and <code>post('updateMany')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateMany({ name: <span class="hljs-regexp">/Stark$/</span> }, { isDeleted: <span class="hljs-literal">true</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateMany()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="query_Query-updateOne"><a href="#query_Query-updateOne">Query.prototype.updateOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as an updateOne() operation. Same as <code>update()</code>, except it does not support the <code>multi</code> or <code>overwrite</code> options.</p>
-
-<ul>
-<li>MongoDB will update <em>only</em> the first document that matches <code>filter</code> regardless of the value of the <code>multi</code> option.</li>
-<li>Use <code>replaceOne()</code> if you want to overwrite an entire document rather than using <a href="https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern">atomic</a> operators like <code>$set</code>.</li>
-</ul>
-
-<p><strong>Note</strong> updateOne will <em>not</em> fire update middleware. Use <code>pre('updateOne')</code> and <code>post('updateOne')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateOne({ name: <span class="hljs-string">'Jean-Luc Picard'</span> }, { ship: <span class="hljs-string">'USS Enterprise'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateOne()</code></li>
-</ul></div><hr class="separate-api-elements"><h3 id="query_Query-use$geoWithin"><a href="#query_Query-use$geoWithin">Query.prototype.use$geoWithin</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Flag to opt out of using <code>$geoWithin</code>.</p>
-
-<pre><code>mongoose.Query.use$geoWithin = <span class="hljs-literal">false</span>;</code></pre>
-
-<p>MongoDB 2.4 deprecated the use of <code>$within</code>, replacing it with <code>$geoWithin</code>. Mongoose uses <code>$geoWithin</code> by default (which is 100% backward compatible with <code>$within</code>). If you are running an older version of MongoDB, set this flag to <code>false</code> so your <code>within()</code> queries continue to work.</p></div><hr class="separate-api-elements"><h3 id="query_Query-w"><a href="#query_Query-w">Query.prototype.w()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;String|number&raquo;</span> 0 for fire-and-forget, 1 for acknowledged by one server, &#39;majority&#39; for majority of the replica set, or <a href="https://docs.mongodb.com/manual/reference/write-concern/#w-option">any of the more advanced options</a>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the specified number of <code>mongod</code> servers, or tag set of <code>mongod</code> servers, that must acknowledge this write before this write is considered successful.</p>
-
-<h2>This option is only valid for operations that write to the database</h2>
-
-<ul>
-<li><code>deleteOne()</code></li>
-<li><code>deleteMany()</code></li>
-<li><code>findOneAndDelete()</code></li>
-<li><code>findOneAndReplace()</code></li>
-<li><code>findOneAndUpdate()</code></li>
-<li><code>remove()</code></li>
-<li><code>update()</code></li>
-<li><code>updateOne()</code></li>
-<li><code>updateMany()</code></li>
-</ul>
-
-<p>Defaults to the schema's <a href="/docs/guide.html#writeConcern"><code>writeConcern.w</code> option</a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// The 'majority' option means the `deleteOne()` promise won't resolve</span>
-<span class="hljs-comment">// until the `deleteOne()` has propagated to the majority of the replica set</span>
-<span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).
-  deleteOne({ name: <span class="hljs-string">'Ned Stark'</span> }).
-  w(<span class="hljs-string">'majority'</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-where"><a href="#query_Query-where">Query.prototype.where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String|Object&raquo;</span> </li><li class="param">[val]
-<span class="method-type">&laquo;any&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>path</code> for use with chaining.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// instead of writing:</span>
-User.find({age: {$gte: <span class="hljs-number">21</span>, $lte: <span class="hljs-number">65</span>}}, callback);
-
-<span class="hljs-comment">// we can instead write:</span>
-User.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>);
-
-<span class="hljs-comment">// passing query conditions is permitted</span>
-User.find().where({ name: <span class="hljs-string">'vonderful'</span> })
-
-<span class="hljs-comment">// chaining</span>
-User
-.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>)
-.where(<span class="hljs-string">'name'</span>, <span class="hljs-regexp">/^vonderful/i</span>)
-.where(<span class="hljs-string">'friends'</span>).slice(<span class="hljs-number">10</span>)
-.exec(callback)</code></pre></div><hr class="separate-api-elements"><h3 id="query_Query-within"><a href="#query_Query-within">Query.prototype.within()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Defines a <code>$within</code> or <code>$geoWithin</code> argument for geo-spatial queries.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(path).within().box()
-query.where(path).within().circle()
-query.where(path).within().geometry()
-
-query.where(<span class="hljs-string">'loc'</span>).within({ center: [<span class="hljs-number">50</span>,<span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span>, unique: <span class="hljs-literal">true</span>, spherical: <span class="hljs-literal">true</span> });
-query.where(<span class="hljs-string">'loc'</span>).within({ box: [[<span class="hljs-number">40.73</span>, <span class="hljs-number">-73.9</span>], [<span class="hljs-number">40.7</span>, <span class="hljs-number">-73.988</span>]] });
-query.where(<span class="hljs-string">'loc'</span>).within({ polygon: [[],[],[],[]] });
-
-query.where(<span class="hljs-string">'loc'</span>).within([], [], []) <span class="hljs-comment">// polygon</span>
-query.where(<span class="hljs-string">'loc'</span>).within([], []) <span class="hljs-comment">// box</span>
-query.where(<span class="hljs-string">'loc'</span>).within({ type: <span class="hljs-string">'LineString'</span>, coordinates: [...] }); <span class="hljs-comment">// geometry</span></code></pre>
-
-<p><strong>MUST</strong> be used after <code>where()</code>.</p>
-
-<h4>NOTE:</h4>
-
-<p>As of Mongoose 3.7, <code>$geoWithin</code> is always used for queries. To change this behavior, see <a href="#query_Query-use%2524geoWithin">Query.use$geoWithin</a>.</p>
-
-<h4>NOTE:</h4>
-
-<p>In Mongoose 3.7, <code>within</code> changed from a getter to a function. If you need the old syntax, use <a href="https://github.com/ebensing/mongoose-within">this</a>.</p></div><hr class="separate-api-elements"><h3 id="query_Query-wtimeout"><a href="#query_Query-wtimeout">Query.prototype.wtimeout()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ms
-<span class="method-type">&laquo;number&raquo;</span> number of milliseconds to wait</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>If <a href="/docs/api.html#query_Query-w"><code>w > 1</code></a>, the maximum amount of time to wait for this write to propagate through the replica set before this operation fails. The default is <code>0</code>, which means no timeout.</p>
-
-<h2>This option is only valid for operations that write to the database</h2>
-
-<ul>
-<li><code>deleteOne()</code></li>
-<li><code>deleteMany()</code></li>
-<li><code>findOneAndDelete()</code></li>
-<li><code>findOneAndReplace()</code></li>
-<li><code>findOneAndUpdate()</code></li>
-<li><code>remove()</code></li>
-<li><code>update()</code></li>
-<li><code>updateOne()</code></li>
-<li><code>updateMany()</code></li>
-</ul>
-
-<p>Defaults to the schema's <a href="/docs/guide.html#writeConcern"><code>writeConcern.wtimeout</code> option</a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// The `deleteOne()` promise won't resolve until this `deleteOne()` has</span>
-<span class="hljs-comment">// propagated to at least `w = 2` members of the replica set. If it takes</span>
-<span class="hljs-comment">// longer than 1 second, this `deleteOne()` will fail.</span>
-<span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).
-  deleteOne({ name: <span class="hljs-string">'Ned Stark'</span> }).
-  w(<span class="hljs-number">2</span>).
-  wtimeout(<span class="hljs-number">1000</span>);</code></pre></div><hr class="separate-api"><h2 class="item-header" id="QueryCursor"><a href="#QueryCursor">QueryCursor</a></h2><ul><li><a href="#querycursor_QueryCursor">QueryCursor()</a></li><li><a href="#querycursor_QueryCursor-addCursorFlag">QueryCursor.prototype.addCursorFlag()</a></li><li><a href="#querycursor_QueryCursor-close">QueryCursor.prototype.close()</a></li><li><a href="#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></li><li><a href="#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></li><li><a href="#querycursor_QueryCursor-next">QueryCursor.prototype.next()</a></li></ul><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor"><a href="#querycursor_QueryCursor">QueryCursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">query
-<span class="method-type">&laquo;Query&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> query options passed to <code>.find()</code></li></ul><div><p>A QueryCursor is a concurrency primitive for processing query results one document at a time. A QueryCursor fulfills the Node.js streams3 API, in addition to several other mechanisms for loading documents from MongoDB one at a time.</p>
-
-<p>QueryCursors execute the model's pre find hooks, but <strong>not</strong> the model's post find hooks.</p>
-
-<p>Unless you're an advanced user, do <strong>not</strong> instantiate this class directly. Use <a href="/docs/api.html#query_Query-cursor"><code>Query#cursor()</code></a> instead.</p></div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-addCursorFlag"><a href="#querycursor_QueryCursor-addCursorFlag">QueryCursor.prototype.addCursorFlag()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">flag
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;AggregationCursor&raquo;</span> this</li></ul><div><p>Adds a <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag">cursor flag</a>. Useful for setting the <code>noCursorTimeout</code> and <code>tailable</code> flags.</p></div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-close"><a href="#querycursor_QueryCursor-close">QueryCursor.prototype.close()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Marks this cursor as closed. Will stop streaming and subsequent calls to <code>next()</code> will error.</p></div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-eachAsync"><a href="#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.parallel]
-<span class="method-type">&laquo;Number&raquo;</span> the number of promises to execute in parallel. Defaults to 1.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> executed when all docs have been processed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute <code>fn</code> for every document in the cursor. If <code>fn</code> returns a promise, will wait for the promise to resolve before iterating on to the next one. Returns a promise that resolves when done.</p></div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-map"><a href="#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;QueryCursor&raquo;</span> </li></ul><div><p>Registers a transform function which subsequently maps documents retrieved via the streams interface or <code>.next()</code></p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Map documents returned by `data` events</span>
-Thing.
-  find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-   doc.foo = <span class="hljs-string">"bar"</span>;
-   <span class="hljs-keyword">return</span> doc;
-  })
-  on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{ <span class="hljs-built_in">console</span>.log(doc.foo); });
-
-<span class="hljs-comment">// Or map documents returned by `.next()`</span>
-<span class="hljs-keyword">var</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-    doc.foo = <span class="hljs-string">"bar"</span>;
-    <span class="hljs-keyword">return</span> doc;
-  });
-cursor.next(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.foo);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-next"><a href="#querycursor_QueryCursor-next">QueryCursor.prototype.next()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Get the next document from this cursor. Will return <code>null</code> when there are no documents left.</p></div><hr class="separate-api"><h2 class="item-header" id="Aggregate"><a href="#Aggregate">Aggregate</a></h2><ul><li><a href="#aggregate_Aggregate">Aggregate()</a></li><li><a href="#aggregate_Aggregate-Symbol.asyncIterator">Aggregate.prototype.Symbol.asyncIterator()</a></li><li><a href="#aggregate_Aggregate-addCursorFlag">Aggregate.prototype.addCursorFlag</a></li><li><a href="#aggregate_Aggregate-addFields">Aggregate.prototype.addFields()</a></li><li><a href="#aggregate_Aggregate-allowDiskUse">Aggregate.prototype.allowDiskUse()</a></li><li><a href="#aggregate_Aggregate-append">Aggregate.prototype.append()</a></li><li><a href="#aggregate_Aggregate-catch">Aggregate.prototype.catch()</a></li><li><a href="#aggregate_Aggregate-collation">Aggregate.prototype.collation()</a></li><li><a href="#aggregate_Aggregate-count">Aggregate.prototype.count()</a></li><li><a href="#aggregate_Aggregate-cursor">Aggregate.prototype.cursor()</a></li><li><a href="#aggregate_Aggregate-exec">Aggregate.prototype.exec()</a></li><li><a href="#aggregate_Aggregate-explain">Aggregate.prototype.explain()</a></li><li><a href="#aggregate_Aggregate-facet">Aggregate.prototype.facet()</a></li><li><a href="#aggregate_Aggregate-graphLookup">Aggregate.prototype.graphLookup()</a></li><li><a href="#aggregate_Aggregate-group">Aggregate.prototype.group()</a></li><li><a href="#aggregate_Aggregate-hint">Aggregate.prototype.hint()</a></li><li><a href="#aggregate_Aggregate-limit">Aggregate.prototype.limit()</a></li><li><a href="#aggregate_Aggregate-lookup">Aggregate.prototype.lookup()</a></li><li><a href="#aggregate_Aggregate-match">Aggregate.prototype.match()</a></li><li><a href="#aggregate_Aggregate-model">Aggregate.prototype.model()</a></li><li><a href="#aggregate_Aggregate-near">Aggregate.prototype.near()</a></li><li><a href="#aggregate_Aggregate-option">Aggregate.prototype.option()</a></li><li><a href="#aggregate_Aggregate-options">Aggregate.prototype.options</a></li><li><a href="#aggregate_Aggregate-pipeline">Aggregate.prototype.pipeline()</a></li><li><a href="#aggregate_Aggregate-project">Aggregate.prototype.project()</a></li><li><a href="#aggregate_Aggregate-read">Aggregate.prototype.read()</a></li><li><a href="#aggregate_Aggregate-readConcern">Aggregate.prototype.readConcern()</a></li><li><a href="#aggregate_Aggregate-redact">Aggregate.prototype.redact()</a></li><li><a href="#aggregate_Aggregate-replaceRoot">Aggregate.prototype.replaceRoot()</a></li><li><a href="#aggregate_Aggregate-sample">Aggregate.prototype.sample()</a></li><li><a href="#aggregate_Aggregate-session">Aggregate.prototype.session()</a></li><li><a href="#aggregate_Aggregate-skip">Aggregate.prototype.skip()</a></li><li><a href="#aggregate_Aggregate-sort">Aggregate.prototype.sort()</a></li><li><a href="#aggregate_Aggregate-sortByCount">Aggregate.prototype.sortByCount()</a></li><li><a href="#aggregate_Aggregate-then">Aggregate.prototype.then()</a></li><li><a href="#aggregate_Aggregate-unwind">Aggregate.prototype.unwind()</a></li></ul><hr class="separate-api-elements"><h3 id="aggregate_Aggregate"><a href="#aggregate_Aggregate">Aggregate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[pipeline]
-<span class="method-type">&laquo;Array&raquo;</span> aggregation pipeline as an array of objects</li></ul><div><p>Aggregate constructor used for building aggregation pipelines. Do not instantiate this class directly, use <a href="/docs/api.html#model_Model.aggregate">Model.aggregate()</a> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> aggregate = Model.aggregate([
-  { $project: { a: <span class="hljs-number">1</span>, b: <span class="hljs-number">1</span> } },
-  { $skip: <span class="hljs-number">5</span> }
-]);
-
-Model.
-  aggregate([{ $match: { age: { $gte: <span class="hljs-number">21</span> }}}]).
-  unwind(<span class="hljs-string">'tags'</span>).
-  exec(callback);</code></pre>
-
-<h4>Note:</h4>
-
-<ul>
-<li>The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).</li>
-<li>Mongoose does <strong>not</strong> cast pipeline stages. The below will <strong>not</strong> work unless <code>_id</code> is a string in the database</li>
-</ul>
-
-<div class="highlight"><pre lang="javascript">  new Aggregate([{ $match: { _id: '00000000000000000000000a' } }]);
-  // Do this instead to cast to an ObjectId
-  new Aggregate([{ $match: { _id: mongoose.Types.ObjectId('00000000000000000000000a') } }]);
-</pre></div></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-Symbol.asyncIterator"><a href="#aggregate_Aggregate-Symbol.asyncIterator">Aggregate.prototype.Symbol.asyncIterator()</a></h3><div><p>Returns an asyncIterator for use with <a href="http://bit.ly/async-iterators"><code>for/await/of</code> loops</a> This function <em>only</em> works for <code>find()</code> queries. You do not need to call this function explicitly, the JavaScript runtime will call it for you.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> doc <span class="hljs-keyword">of</span> Model.find().sort({ name: <span class="hljs-number">1</span> })) {
-  <span class="hljs-built_in">console</span>.log(doc.name);
-}</code></pre>
-
-<p>Node.js 10.x supports async iterators natively without any flags. You can enable async iterators in Node.js 8.x using the <a href="https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187"><code>--harmony_async_iteration</code> flag</a>.</p>
-
-<p><strong>Note:</strong> This function is not if <code>Symbol.asyncIterator</code> is undefined. If <code>Symbol.asyncIterator</code> is undefined, that means your Node.js version does not support async iterators.</p></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-addCursorFlag"><a href="#aggregate_Aggregate-addCursorFlag">Aggregate.prototype.addCursorFlag</a></h3><h5>Parameters</h5><ul class="params"><li class="param">flag
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Sets an option on this aggregation. This function will be deprecated in a future release. Use the <a href="./api.html#aggregate_Aggregate-cursor"><code>cursor()</code></a>, <a href="./api.html#aggregate_Aggregate-collation"><code>collation()</code></a>, etc. helpers to set individual options, or access <code>agg.options</code> directly.</p>
-
-<p>Note that MongoDB aggregations <a href="https://jira.mongodb.org/browse/SERVER-6036">do <strong>not</strong> support the <code>noCursorTimeout</code> flag</a>, if you try setting that flag with this function you will get a "unrecognized field 'noCursorTimeout'" error.</p></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-addFields"><a href="#aggregate_Aggregate-addFields">Aggregate.prototype.addFields()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> field specification</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $addFields operator to this aggregate pipeline. Requires MongoDB v3.4+ to work</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// adding new fields based on existing fields</span>
-aggregate.addFields({
-    newField: <span class="hljs-string">'$b.nested'</span>
-  , plusTen: { $add: [<span class="hljs-string">'$val'</span>, <span class="hljs-number">10</span>]}
-  , sub: {
-       name: <span class="hljs-string">'$a'</span>
-    }
-})
-
-<span class="hljs-comment">// etc</span>
-aggregate.addFields({ salary_k: { $divide: [ <span class="hljs-string">"$salary"</span>, <span class="hljs-number">1000</span> ] } });</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-allowDiskUse"><a href="#aggregate_Aggregate-allowDiskUse">Aggregate.prototype.allowDiskUse()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> Should tell server it can use hard drive to store data during aggregation.</li><li class="param">[tags]
-<span class="method-type">&laquo;Array&raquo;</span> optional tags for this query</li></ul><div><p>Sets the allowDiskUse option for the aggregation query (ignored for &lt; 2.6.0)</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> Model.aggregate([{ $match: { foo: <span class="hljs-string">'bar'</span> } }]).allowDiskUse(<span class="hljs-literal">true</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-append"><a href="#aggregate_Aggregate-append">Aggregate.prototype.append()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ops
-<span class="method-type">&laquo;Object&raquo;</span> operator(s) to append</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new operators to this aggregate pipeline</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.append({ $project: { field: <span class="hljs-number">1</span> }}, { $limit: <span class="hljs-number">2</span> });
-
-<span class="hljs-comment">// or pass an array</span>
-<span class="hljs-keyword">var</span> pipeline = [{ $match: { daw: <span class="hljs-string">'Logic Audio X'</span> }} ];
-aggregate.append(pipeline);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-catch"><a href="#aggregate_Aggregate-catch">Aggregate.prototype.catch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query returning a <code>Promise</code> which will be resolved with either the doc(s) or rejected with the error. Like <a href="#query_Query-then"><code>.then()</code></a>, but only takes a rejection handler.</p></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-collation"><a href="#aggregate_Aggregate-collation">Aggregate.prototype.collation()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">collation
-<span class="method-type">&laquo;Object&raquo;</span> options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Adds a collation</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).collation({ locale: <span class="hljs-string">'en_US'</span>, strength: <span class="hljs-number">1</span> }).exec();</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-count"><a href="#aggregate_Aggregate-count">Aggregate.prototype.count()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">the
-<span class="method-type">&laquo;String&raquo;</span> name of the count field</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $count operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.count(<span class="hljs-string">"userCount"</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-cursor"><a href="#aggregate_Aggregate-cursor">Aggregate.prototype.cursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options.batchSize
-<span class="method-type">&laquo;Number&raquo;</span> set the cursor batch size</li><ul style="margin-top: 0.5em"><li>[options.useMongooseAggCursor]
-<span class="method-type">&laquo;Boolean&raquo;</span> use experimental mongoose-specific aggregation cursor (for <code>eachAsync()</code> and other query cursor semantics)</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Sets the cursor option option for the aggregation query (ignored for &lt; 2.6.0). Note the different syntax below: .exec() returns a cursor object, and no callback is necessary.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> cursor = Model.aggregate(..).cursor({ batchSize: <span class="hljs-number">1000</span> }).exec();
-cursor.eachAsync(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// use doc</span>
-});</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-exec"><a href="#aggregate_Aggregate-exec">Aggregate.prototype.exec()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the aggregate pipeline on the currently bound Model.</p>
-
-<h4>Example:</h4>
-
-<pre><code>aggregate.exec(callback);
-
-<span class="hljs-comment">// Because a promise is returned, the `callback` is optional.</span>
-<span class="hljs-keyword">var</span> promise = aggregate.exec();
-promise.then(..);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-explain"><a href="#aggregate_Aggregate-explain">Aggregate.prototype.explain()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute the aggregation with explain</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).explain(callback)</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-facet"><a href="#aggregate_Aggregate-facet">Aggregate.prototype.facet()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">facet
-<span class="method-type">&laquo;Object&raquo;</span> options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Combines multiple aggregation pipelines.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(...)
- .facet({
-   books: [{ groupBy: <span class="hljs-string">'$author'</span> }],
-   price: [{ $bucketAuto: { groupBy: <span class="hljs-string">'$price'</span>, buckets: <span class="hljs-number">2</span> } }]
- })
- .exec();
-
-<span class="hljs-comment">// Output: { books: [...], price: [{...}, {...}] }</span></code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-graphLookup"><a href="#aggregate_Aggregate-graphLookup">Aggregate.prototype.graphLookup()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> to $graphLookup as described in the above link</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection.</p>
-
-<p>Note that graphLookup can only consume at most 100MB of memory, and does not allow disk use even if <code>{ allowDiskUse: true }</code> is specified.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// Suppose we have a collection of courses, where a document might look like `{ _id: 0, name: 'Calculus', prerequisite: 'Trigonometry'}` and `{ _id: 0, name: 'Trigonometry', prerequisite: 'Algebra' }`</span>
- aggregate.graphLookup({ <span class="hljs-keyword">from</span>: <span class="hljs-string">'courses'</span>, startWith: <span class="hljs-string">'$prerequisite'</span>, connectFromField: <span class="hljs-string">'prerequisite'</span>, connectToField: <span class="hljs-string">'name'</span>, <span class="hljs-keyword">as</span>: <span class="hljs-string">'prerequisites'</span>, maxDepth: <span class="hljs-number">3</span> }) <span class="hljs-comment">// this will recursively search the 'courses' collection up to 3 prerequisites</span></code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-group"><a href="#aggregate_Aggregate-group">Aggregate.prototype.group()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> $group operator contents</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new custom $group operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.group({ _id: <span class="hljs-string">"$department"</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-hint"><a href="#aggregate_Aggregate-hint">Aggregate.prototype.hint()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object|String&raquo;</span> a hint object or the index name</li></ul><div><p>Sets the hint option for the aggregation query (ignored for &lt; 3.6.0)</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).hint({ qty: <span class="hljs-number">1</span>, category: <span class="hljs-number">1</span> }).exec(callback)</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-limit"><a href="#aggregate_Aggregate-limit">Aggregate.prototype.limit()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">num
-<span class="method-type">&laquo;Number&raquo;</span> maximum number of records to pass to the next stage</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $limit operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.limit(<span class="hljs-number">10</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-lookup"><a href="#aggregate_Aggregate-lookup">Aggregate.prototype.lookup()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> to $lookup as described in the above link</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $lookup operator(s) to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.lookup({ <span class="hljs-keyword">from</span>: <span class="hljs-string">'users'</span>, localField: <span class="hljs-string">'userId'</span>, foreignField: <span class="hljs-string">'_id'</span>, <span class="hljs-keyword">as</span>: <span class="hljs-string">'users'</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-match"><a href="#aggregate_Aggregate-match">Aggregate.prototype.match()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> $match operator contents</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new custom $match operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.match({ department: { $<span class="hljs-keyword">in</span>: [ <span class="hljs-string">"sales"</span>, <span class="hljs-string">"engineering"</span> ] } });</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-model"><a href="#aggregate_Aggregate-model">Aggregate.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[model]
-<span class="method-type">&laquo;Model&raquo;</span> the model to which the aggregate is to be bound</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate,Model&raquo;</span> if model is passed, will return <code>this</code>, otherwise will return the model</li></ul><div><p>Get/set the model that this aggregation will execute on.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> aggregate = MyModel.aggregate([{ $match: { answer: <span class="hljs-number">42</span> } }]);
-aggregate.model() === MyModel; <span class="hljs-comment">// true</span>
-
-<span class="hljs-comment">// Change the model. There's rarely any reason to do this.</span>
-aggregate.model(SomeOtherModel);
-aggregate.model() === SomeOtherModel; <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-near"><a href="#aggregate_Aggregate-near">Aggregate.prototype.near()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $geoNear operator to this aggregate pipeline.</p>
-
-<h4>NOTE:</h4>
-
-<p><strong>MUST</strong> be used as the first operator in the pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.near({
-  near: [<span class="hljs-number">40.724</span>, <span class="hljs-number">-73.997</span>],
-  distanceField: <span class="hljs-string">"dist.calculated"</span>, <span class="hljs-comment">// required</span>
-  maxDistance: <span class="hljs-number">0.008</span>,
-  query: { type: <span class="hljs-string">"public"</span> },
-  includeLocs: <span class="hljs-string">"dist.location"</span>,
-  uniqueDocs: <span class="hljs-literal">true</span>,
-  num: <span class="hljs-number">5</span>
-});</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-option"><a href="#aggregate_Aggregate-option">Aggregate.prototype.option()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> keys to merge into current options</li><li class="param">number
-<span class="method-type">&laquo;[options.maxTimeMS]&raquo;</span> limits the time this aggregation will run, see <a href="https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/">MongoDB docs on <code>maxTimeMS</code></a></li><li class="param">boolean
-<span class="method-type">&laquo;[options.allowDiskUse]&raquo;</span> if true, the MongoDB server will use the hard drive to store data during this aggregation</li><li class="param">object
-<span class="method-type">&laquo;[options.collation]&raquo;</span> see <a href="./docs/api.html#aggregate_Aggregate-collation"><code>Aggregate.prototype.collation()</code></a></li><li class="param">ClientSession
-<span class="method-type">&laquo;[options.session]&raquo;</span> see <a href="./docs/api.html#aggregate_Aggregate-session"><code>Aggregate.prototype.session()</code></a></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Lets you set arbitrary options, for middleware or plugins.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> agg = Model.aggregate(..).option({ allowDiskUse: <span class="hljs-literal">true</span> }); <span class="hljs-comment">// Set the `allowDiskUse` option</span>
-agg.options; <span class="hljs-comment">// `{ allowDiskUse: true }`</span></code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-options"><a href="#aggregate_Aggregate-options">Aggregate.prototype.options</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Contains options passed down to the <a href="https://docs.mongodb.com/manual/reference/command/aggregate/">aggregate command</a>.</p>
-
-<h2>Supported options are</h2>
-
-<ul>
-<li><code>readPreference</code></li>
-<li><a href="./api.html#aggregate_Aggregate-cursor"><code>cursor</code></a></li>
-<li><a href="./api.html#aggregate_Aggregate-explain"><code>explain</code></a></li>
-<li><a href="./api.html#aggregate_Aggregate-allowDiskUse"><code>allowDiskUse</code></a></li>
-<li><code>maxTimeMS</code></li>
-<li><code>bypassDocumentValidation</code></li>
-<li><code>raw</code></li>
-<li><code>promoteLongs</code></li>
-<li><code>promoteValues</code></li>
-<li><code>promoteBuffers</code></li>
-<li><a href="./api.html#aggregate_Aggregate-collation"><code>collation</code></a></li>
-<li><code>comment</code></li>
-<li><a href="./api.html#aggregate_Aggregate-session"><code>session</code></a></li>
-</ul></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-pipeline"><a href="#aggregate_Aggregate-pipeline">Aggregate.prototype.pipeline()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns the current pipeline</p>
-
-<h4>Example:</h4>
-
-<pre><code>MyModel.aggregate().match({ test: <span class="hljs-number">1</span> }).pipeline(); <span class="hljs-comment">// [{ $match: { test: 1 } }]</span></code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-project"><a href="#aggregate_Aggregate-project">Aggregate.prototype.project()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> field specification</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $project operator to this aggregate pipeline.</p>
-
-<p>Mongoose query <a href="#query_Query-select">selection syntax</a> is also supported.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// include a, include b, exclude _id</span>
-aggregate.project(<span class="hljs-string">"a b -_id"</span>);
-
-<span class="hljs-comment">// or you may use object notation, useful when</span>
-<span class="hljs-comment">// you have keys already prefixed with a "-"</span>
-aggregate.project({a: <span class="hljs-number">1</span>, b: <span class="hljs-number">1</span>, _id: <span class="hljs-number">0</span>});
-
-<span class="hljs-comment">// reshaping documents</span>
-aggregate.project({
-    newField: <span class="hljs-string">'$b.nested'</span>
-  , plusTen: { $add: [<span class="hljs-string">'$val'</span>, <span class="hljs-number">10</span>]}
-  , sub: {
-       name: <span class="hljs-string">'$a'</span>
-    }
-})
-
-<span class="hljs-comment">// etc</span>
-aggregate.project({ salary_k: { $divide: [ <span class="hljs-string">"$salary"</span>, <span class="hljs-number">1000</span> ] } });</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-read"><a href="#aggregate_Aggregate-read">Aggregate.prototype.read()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">pref
-<span class="method-type">&laquo;String&raquo;</span> one of the listed preference options or their aliases</li><li class="param">[tags]
-<span class="method-type">&laquo;Array&raquo;</span> optional tags for this query</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Sets the readPreference option for the aggregation query.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).read(<span class="hljs-string">'primaryPreferred'</span>).exec(callback)</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-readConcern"><a href="#aggregate_Aggregate-readConcern">Aggregate.prototype.readConcern()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">level
-<span class="method-type">&laquo;String&raquo;</span> one of the listed read concern level or their aliases</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Sets the readConcern level for the aggregation query.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).readConcern(<span class="hljs-string">'majority'</span>).exec(callback)</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-redact"><a href="#aggregate_Aggregate-redact">Aggregate.prototype.redact()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">expression
-<span class="method-type">&laquo;Object&raquo;</span> redact options or conditional expression</li><li class="param">[thenExpr]
-<span class="method-type">&laquo;String|Object&raquo;</span> true case for the condition</li><li class="param">[elseExpr]
-<span class="method-type">&laquo;String|Object&raquo;</span> false case for the condition</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Appends a new $redact operator to this aggregate pipeline.</p>
-
-<p>If 3 arguments are supplied, Mongoose will wrap them with if-then-else of $cond operator respectively If <code>thenExpr</code> or <code>elseExpr</code> is string, make sure it starts with $$, like <code>$$DESCEND</code>, <code>$$PRUNE</code> or <code>$$KEEP</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(...)
- .redact({
-   $cond: {
-     <span class="hljs-keyword">if</span>: { $eq: [ <span class="hljs-string">'$level'</span>, <span class="hljs-number">5</span> ] },
-     then: <span class="hljs-string">'$$PRUNE'</span>,
-     <span class="hljs-keyword">else</span>: <span class="hljs-string">'$$DESCEND'</span>
-   }
- })
- .exec();
-
-<span class="hljs-comment">// $redact often comes with $cond operator, you can also use the following syntax provided by mongoose</span>
-Model.aggregate(...)
- .redact({ $eq: [ <span class="hljs-string">'$level'</span>, <span class="hljs-number">5</span> ] }, <span class="hljs-string">'$$PRUNE'</span>, <span class="hljs-string">'$$DESCEND'</span>)
- .exec();</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-replaceRoot"><a href="#aggregate_Aggregate-replaceRoot">Aggregate.prototype.replaceRoot()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">the
-<span class="method-type">&laquo;String|Object&raquo;</span> field or document which will become the new root document</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $replaceRoot operator to this aggregate pipeline.</p>
-
-<p>Note that the <code>$replaceRoot</code> operator requires field strings to start with '$'. If you are passing in a string Mongoose will prepend '$' if the specified field doesn't start '$'. If you are passing in an object the strings in your expression will not be altered.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.replaceRoot(<span class="hljs-string">"user"</span>);
-
-aggregate.replaceRoot({ x: { $concat: [<span class="hljs-string">'$this'</span>, <span class="hljs-string">'$that'</span>] } });</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-sample"><a href="#aggregate_Aggregate-sample">Aggregate.prototype.sample()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">size
-<span class="method-type">&laquo;Number&raquo;</span> number of random documents to pick</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $sample operator(s) to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.sample(<span class="hljs-number">3</span>); <span class="hljs-comment">// Add a pipeline that picks 3 random documents</span></code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-session"><a href="#aggregate_Aggregate-session">Aggregate.prototype.session()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">session
-<span class="method-type">&laquo;ClientSession&raquo;</span> </li></ul><div><p>Sets the session for this aggregation. Useful for <a href="/docs/transactions.html">transactions</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = <span class="hljs-keyword">await</span> Model.startSession();
-<span class="hljs-keyword">await</span> Model.aggregate(..).session(session);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-skip"><a href="#aggregate_Aggregate-skip">Aggregate.prototype.skip()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">num
-<span class="method-type">&laquo;Number&raquo;</span> number of records to skip before next stage</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $skip operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.skip(<span class="hljs-number">10</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-sort"><a href="#aggregate_Aggregate-sort">Aggregate.prototype.sort()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Appends a new $sort operator to this aggregate pipeline.</p>
-
-<p>If an object is passed, values allowed are <code>asc</code>, <code>desc</code>, <code>ascending</code>, <code>descending</code>, <code>1</code>, and <code>-1</code>.</p>
-
-<p>If a string is passed, it must be a space delimited list of path names. The sort order of each path is ascending unless the path name is prefixed with <code>-</code> which will be treated as descending.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// these are equivalent</span>
-aggregate.sort({ field: <span class="hljs-string">'asc'</span>, test: <span class="hljs-number">-1</span> });
-aggregate.sort(<span class="hljs-string">'field -test'</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-sortByCount"><a href="#aggregate_Aggregate-sortByCount">Aggregate.prototype.sortByCount()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Appends a new $sortByCount operator to this aggregate pipeline. Accepts either a string field name or a pipeline object.</p>
-
-<p>Note that the <code>$sortByCount</code> operator requires the new root to start with '$'. Mongoose will prepend '$' if the specified field name doesn't start with '$'.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.sortByCount(<span class="hljs-string">'users'</span>);
-aggregate.sortByCount({ $mergeObjects: [ <span class="hljs-string">"$employee"</span>, <span class="hljs-string">"$business"</span> ] })</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-then"><a href="#aggregate_Aggregate-then">Aggregate.prototype.then()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[resolve]
-<span class="method-type">&laquo;Function&raquo;</span> successCallback</li><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> errorCallback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Provides promise for aggregate.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).then(successCallback, errorCallback);</code></pre></div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-unwind"><a href="#aggregate_Aggregate-unwind">Aggregate.prototype.unwind()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fields
-<span class="method-type">&laquo;String&raquo;</span> the field(s) to unwind</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $unwind operator(s) to this aggregate pipeline.</p>
-
-<p>Note that the <code>$unwind</code> operator requires the path name to start with '$'. Mongoose will prepend '$' if the specified field doesn't start '$'.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.unwind(<span class="hljs-string">"tags"</span>);
-aggregate.unwind(<span class="hljs-string">"a"</span>, <span class="hljs-string">"b"</span>, <span class="hljs-string">"c"</span>);</code></pre></div><hr class="separate-api"><h2 class="item-header" id="AggregationCursor"><a href="#AggregationCursor">AggregationCursor</a></h2><ul><li><a href="#aggregationcursor_AggregationCursor">AggregationCursor()</a></li><li><a href="#aggregationcursor_AggregationCursor-addCursorFlag">AggregationCursor.prototype.addCursorFlag()</a></li><li><a href="#aggregationcursor_AggregationCursor-close">AggregationCursor.prototype.close()</a></li><li><a href="#aggregationcursor_AggregationCursor-eachAsync">AggregationCursor.prototype.eachAsync()</a></li><li><a href="#aggregationcursor_AggregationCursor-map">AggregationCursor.prototype.map()</a></li><li><a href="#aggregationcursor_AggregationCursor-next">AggregationCursor.prototype.next()</a></li></ul><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor"><a href="#aggregationcursor_AggregationCursor">AggregationCursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">agg
-<span class="method-type">&laquo;Aggregate&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>An AggregationCursor is a concurrency primitive for processing aggregation results one document at a time. It is analogous to QueryCursor.</p>
-
-<p>An AggregationCursor fulfills the Node.js streams3 API, in addition to several other mechanisms for loading documents from MongoDB one at a time.</p>
-
-<p>Creating an AggregationCursor executes the model's pre aggregate hooks, but <strong>not</strong> the model's post aggregate hooks.</p>
-
-<p>Unless you're an advanced user, do <strong>not</strong> instantiate this class directly. Use <a href="/docs/api.html#aggregate_Aggregate-cursor"><code>Aggregate#cursor()</code></a> instead.</p></div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-addCursorFlag"><a href="#aggregationcursor_AggregationCursor-addCursorFlag">AggregationCursor.prototype.addCursorFlag()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">flag
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;AggregationCursor&raquo;</span> this</li></ul><div><p>Adds a <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag">cursor flag</a>. Useful for setting the <code>noCursorTimeout</code> and <code>tailable</code> flags.</p></div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-close"><a href="#aggregationcursor_AggregationCursor-close">AggregationCursor.prototype.close()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Marks this cursor as closed. Will stop streaming and subsequent calls to <code>next()</code> will error.</p></div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-eachAsync"><a href="#aggregationcursor_AggregationCursor-eachAsync">AggregationCursor.prototype.eachAsync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.parallel]
-<span class="method-type">&laquo;Number&raquo;</span> the number of promises to execute in parallel. Defaults to 1.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> executed when all docs have been processed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute <code>fn</code> for every document in the cursor. If <code>fn</code> returns a promise, will wait for the promise to resolve before iterating on to the next one. Returns a promise that resolves when done.</p></div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-map"><a href="#aggregationcursor_AggregationCursor-map">AggregationCursor.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;AggregationCursor&raquo;</span> </li></ul><div><p>Registers a transform function which subsequently maps documents retrieved via the streams interface or <code>.next()</code></p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Map documents returned by `data` events</span>
-Thing.
-  find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-   doc.foo = <span class="hljs-string">"bar"</span>;
-   <span class="hljs-keyword">return</span> doc;
-  })
-  on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{ <span class="hljs-built_in">console</span>.log(doc.foo); });
-
-<span class="hljs-comment">// Or map documents returned by `.next()`</span>
-<span class="hljs-keyword">var</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-    doc.foo = <span class="hljs-string">"bar"</span>;
-    <span class="hljs-keyword">return</span> doc;
-  });
-cursor.next(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.foo);
-});</code></pre></div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-next"><a href="#aggregationcursor_AggregationCursor-next">AggregationCursor.prototype.next()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Get the next document from this cursor. Will return <code>null</code> when there are no documents left.</p></div><hr class="separate-api"><h2 class="item-header" id="Schematype"><a href="#Schematype">Schematype</a></h2><ul><li><a href="#schematype_SchemaType">SchemaType()</a></li><li><a href="#schematype_SchemaType-cast">SchemaType.cast()</a></li><li><a href="#schematype_SchemaType-checkRequired">SchemaType.checkRequired()</a></li><li><a href="#schematype_SchemaType-get">SchemaType.get()</a></li><li><a href="#schematype_SchemaType-default">SchemaType.prototype.default()</a></li><li><a href="#schematype_SchemaType-get">SchemaType.prototype.get()</a></li><li><a href="#schematype_SchemaType-immutable">SchemaType.prototype.immutable()</a></li><li><a href="#schematype_SchemaType-index">SchemaType.prototype.index()</a></li><li><a href="#schematype_SchemaType-ref">SchemaType.prototype.ref()</a></li><li><a href="#schematype_SchemaType-required">SchemaType.prototype.required()</a></li><li><a href="#schematype_SchemaType-select">SchemaType.prototype.select()</a></li><li><a href="#schematype_SchemaType-set">SchemaType.prototype.set()</a></li><li><a href="#schematype_SchemaType-sparse">SchemaType.prototype.sparse()</a></li><li><a href="#schematype_SchemaType-text">SchemaType.prototype.text()</a></li><li><a href="#schematype_SchemaType-unique">SchemaType.prototype.unique()</a></li><li><a href="#schematype_SchemaType-validate">SchemaType.prototype.validate()</a></li></ul><hr class="separate-api-elements"><h3 id="schematype_SchemaType"><a href="#schematype_SchemaType">SchemaType()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[instance]
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>SchemaType constructor. Do <strong>not</strong> instantiate <code>SchemaType</code> directly. Mongoose converts your schema paths into SchemaTypes automatically.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>) <span class="hljs-keyword">instanceof</span> SchemaType; <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-cast"><a href="#schematype_SchemaType-cast">SchemaType.cast()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">caster
-<span class="method-type">&laquo;Function|false&raquo;</span> Function that casts arbitrary values to this type, or throws an error if casting failed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Get/set the function used to cast arbitrary values to this type.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Disallow `null` for numbers, and don't try to cast any values to</span>
-<span class="hljs-comment">// numbers, so even strings like '123' will cause a CastError.</span>
-mongoose.Number.cast(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-  assert.ok(v === <span class="hljs-literal">undefined</span> || <span class="hljs-keyword">typeof</span> v === <span class="hljs-string">'number'</span>);
-  <span class="hljs-keyword">return</span> v;
-});</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-checkRequired"><a href="#schematype_SchemaType-checkRequired">SchemaType.checkRequired()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Override the function the required validator uses to check whether a value passes the <code>required</code> check. Override this on the individual SchemaType.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Use this to allow empty strings to pass the `required` validator</span>
-mongoose.Schema.Types.String.checkRequired(v =&gt; <span class="hljs-keyword">typeof</span> v === <span class="hljs-string">'string'</span>);</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-get"><a href="#schematype_SchemaType-get">SchemaType.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">getter
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;this&raquo;</span> </li></ul><div><p>Attaches a getter for all instances of this schema type.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Make all numbers round down</span>
-mongoose.Number.get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-built_in">Math</span>.floor(v); });</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-default"><a href="#schematype_SchemaType-default">SchemaType.prototype.default()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Function|any&raquo;</span> the default value</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;defaultValue&raquo;</span> </li></ul><div><p>Sets a default value for this SchemaType.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ n: { type: <span class="hljs-built_in">Number</span>, <span class="hljs-keyword">default</span>: <span class="hljs-number">10</span> })
-<span class="hljs-keyword">var</span> M = db.model(<span class="hljs-string">'M'</span>, schema)
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M;
-<span class="hljs-built_in">console</span>.log(m.n) <span class="hljs-comment">// 10</span></code></pre>
-
-<p>Defaults can be either <code>functions</code> which return the value to use as the default or the literal value itself. Either way, the value will be cast based on its schema type before being set during document creation.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// values are cast:</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ aNumber: { type: <span class="hljs-built_in">Number</span>, <span class="hljs-keyword">default</span>: <span class="hljs-number">4.815162342</span> }})
-<span class="hljs-keyword">var</span> M = db.model(<span class="hljs-string">'M'</span>, schema)
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M;
-<span class="hljs-built_in">console</span>.log(m.aNumber) <span class="hljs-comment">// 4.815162342</span>
-
-<span class="hljs-comment">// default unique objects for Mixed types:</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ mixed: Schema.Types.Mixed });
-schema.path(<span class="hljs-string">'mixed'</span>).default(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> {};
-});
-
-<span class="hljs-comment">// if we don't use a function to return object literals for Mixed defaults,</span>
-<span class="hljs-comment">// each document will receive a reference to the same object literal creating</span>
-<span class="hljs-comment">// a "shared" object instance:</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ mixed: Schema.Types.Mixed });
-schema.path(<span class="hljs-string">'mixed'</span>).default({});
-<span class="hljs-keyword">var</span> M = db.model(<span class="hljs-string">'M'</span>, schema);
-<span class="hljs-keyword">var</span> m1 = <span class="hljs-keyword">new</span> M;
-m1.mixed.added = <span class="hljs-number">1</span>;
-<span class="hljs-built_in">console</span>.log(m1.mixed); <span class="hljs-comment">// { added: 1 }</span>
-<span class="hljs-keyword">var</span> m2 = <span class="hljs-keyword">new</span> M;
-<span class="hljs-built_in">console</span>.log(m2.mixed); <span class="hljs-comment">// { added: 1 }</span></code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-get"><a href="#schematype_SchemaType-get">SchemaType.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds a getter to this schematype.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">dob</span> (<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">if</span> (!val) <span class="hljs-keyword">return</span> val;
-  <span class="hljs-keyword">return</span> (val.getMonth() + <span class="hljs-number">1</span>) + <span class="hljs-string">"/"</span> + val.getDate() + <span class="hljs-string">"/"</span> + val.getFullYear();
-}
-
-<span class="hljs-comment">// defining within the schema</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: { type: <span class="hljs-built_in">Date</span>, get: dob })
-
-<span class="hljs-comment">// or by retreiving its SchemaType</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: <span class="hljs-built_in">Date</span> })
-s.path(<span class="hljs-string">'born'</span>).get(dob)</code></pre>
-
-<p>Getters allow you to transform the representation of the data as it travels from the raw mongodb document to the value that you see.</p>
-
-<p>Suppose you are storing credit card numbers and you want to hide everything except the last 4 digits to the mongoose user. You can do so by defining a getter in the following way:</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">obfuscate</span> (<span class="hljs-params">cc</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-string">'****-****-****-'</span> + cc.slice(cc.length<span class="hljs-number">-4</span>, cc.length);
-}
-
-<span class="hljs-keyword">var</span> AccountSchema = <span class="hljs-keyword">new</span> Schema({
-  creditCardNumber: { type: <span class="hljs-built_in">String</span>, get: obfuscate }
-});
-
-<span class="hljs-keyword">var</span> Account = db.model(<span class="hljs-string">'Account'</span>, AccountSchema);
-
-Account.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, found</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(found.creditCardNumber); <span class="hljs-comment">// '****-****-****-1234'</span>
-});</code></pre>
-
-<p>Getters are also passed a second argument, the schematype on which the getter was defined. This allows for tailored behavior based on options passed in the schema.</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">inspector</span> (<span class="hljs-params">val, schematype</span>) </span>{
-  <span class="hljs-keyword">if</span> (schematype.options.required) {
-    <span class="hljs-keyword">return</span> schematype.path + <span class="hljs-string">' is required'</span>;
-  } <span class="hljs-keyword">else</span> {
-    <span class="hljs-keyword">return</span> schematype.path + <span class="hljs-string">' is not'</span>;
-  }
-}
-
-<span class="hljs-keyword">var</span> VirusSchema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span>, get: inspector },
-  taxonomy: { type: <span class="hljs-built_in">String</span>, get: inspector }
-})
-
-<span class="hljs-keyword">var</span> Virus = db.model(<span class="hljs-string">'Virus'</span>, VirusSchema);
-
-Virus.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, virus</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(virus.name);     <span class="hljs-comment">// name is required</span>
-  <span class="hljs-built_in">console</span>.log(virus.taxonomy); <span class="hljs-comment">// taxonomy is not</span>
-})</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-immutable"><a href="#schematype_SchemaType-immutable">SchemaType.prototype.immutable()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Defines this path as immutable. Mongoose prevents you from changing immutable paths unless the parent document has <a href="/docs/api.html#document_Document-isNew"><code>isNew: true</code></a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, immutable: <span class="hljs-literal">true</span> },
-  age: <span class="hljs-built_in">Number</span>
-});
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">await</span> Model.create({ name: <span class="hljs-string">'test'</span> });
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Model.findOne();
-
-doc.isNew; <span class="hljs-comment">// false</span>
-doc.name = <span class="hljs-string">'new name'</span>;
-doc.name; <span class="hljs-comment">// 'test', because `name` is immutable</span></code></pre>
-
-<p>Mongoose also prevents changing immutable properties using <code>updateOne()</code> and <code>updateMany()</code> based on <a href="/docs/guide.html#strict">strict mode</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Mongoose will strip out the `name` update, because `name` is immutable</span>
-Model.updateOne({}, { $set: { name: <span class="hljs-string">'test2'</span> }, $inc: { age: <span class="hljs-number">1</span> } });
-
-<span class="hljs-comment">// If `strict` is set to 'throw', Mongoose will throw an error if you</span>
-<span class="hljs-comment">// update `name`</span>
-<span class="hljs-keyword">const</span> err = <span class="hljs-keyword">await</span> Model.updateOne({}, { name: <span class="hljs-string">'test2'</span> }, { strict: <span class="hljs-string">'throw'</span> }).
-  then(() =&gt; <span class="hljs-literal">null</span>, err =&amp;gt; err);
-err.name; <span class="hljs-comment">// StrictModeError</span>
-
-<span class="hljs-comment">// If `strict` is `false`, Mongoose allows updating `name` even though</span>
-<span class="hljs-comment">// the property is immutable.</span>
-Model.updateOne({}, { name: <span class="hljs-string">'test2'</span> }, { strict: <span class="hljs-literal">false</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-index"><a href="#schematype_SchemaType-index">SchemaType.prototype.index()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object|Boolean|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares the index options for this schematype.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, index: <span class="hljs-literal">true</span> })
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ loc: { type: [<span class="hljs-built_in">Number</span>], index: <span class="hljs-string">'hashed'</span> })
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ loc: { type: [<span class="hljs-built_in">Number</span>], index: <span class="hljs-string">'2d'</span>, sparse: <span class="hljs-literal">true</span> })
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ loc: { type: [<span class="hljs-built_in">Number</span>], index: { type: <span class="hljs-string">'2dsphere'</span>, sparse: <span class="hljs-literal">true</span> }})
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ date: { type: <span class="hljs-built_in">Date</span>, index: { unique: <span class="hljs-literal">true</span>, expires: <span class="hljs-string">'1d'</span> }})
-Schema.path(<span class="hljs-string">'my.path'</span>).index(<span class="hljs-literal">true</span>);
-Schema.path(<span class="hljs-string">'my.date'</span>).index({ expires: <span class="hljs-number">60</span> });
-Schema.path(<span class="hljs-string">'my.path'</span>).index({ unique: <span class="hljs-literal">true</span>, sparse: <span class="hljs-literal">true</span> });</code></pre>
-
-<h4>NOTE:</h4>
-
-<p><em>Indexes are created <a href="https://docs.mongodb.com/manual/core/index-creation/#index-creation-background">in the background</a> by default. If <code>background</code> is set to <code>false</code>, MongoDB will not execute any read/write operations you send until the index build. Specify <code>background: false</code> to override Mongoose's default.</em></p></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-ref"><a href="#schematype_SchemaType-ref">SchemaType.prototype.ref()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ref
-<span class="method-type">&laquo;String|Model|Function&raquo;</span> either a model name, a <a href="https://mongoosejs.com/docs/models.html">Model</a>, or a function that returns a model name or model.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Set the model that this path refers to. This is the option that <a href="https://mongoosejs.com/docs/populate.html">populate</a> looks at to determine the foreign collection it should query.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">const</span> postSchema = <span class="hljs-keyword">new</span> Schema({ user: mongoose.ObjectId });
-postSchema.path(<span class="hljs-string">'user'</span>).ref(<span class="hljs-string">'User'</span>); <span class="hljs-comment">// By model name</span>
-postSchema.path(<span class="hljs-string">'user'</span>).ref(User); <span class="hljs-comment">// Can pass the model as well</span>
-
-<span class="hljs-comment">// Or you can just declare the `ref` inline in your schema</span>
-<span class="hljs-keyword">const</span> postSchema2 = <span class="hljs-keyword">new</span> Schema({
-  user: { type: mongoose.ObjectId, ref: User }
-});</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-required"><a href="#schematype_SchemaType-required">SchemaType.prototype.required()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">required
-<span class="method-type">&laquo;Boolean|Function|Object&raquo;</span> enable/disable the validator, or function that returns required boolean, or options object</li><ul style="margin-top: 0.5em"><li>[options.isRequired]
-<span class="method-type">&laquo;Boolean|Function&raquo;</span> enable/disable the validator, or function that returns required boolean</li></ul><ul style="margin-top: 0.5em"><li>[options.ErrorConstructor]
-<span class="method-type">&laquo;Function&raquo;</span> custom error constructor. The constructor receives 1 parameter, an object containing the validator properties.</li></ul><li class="param">[message]
-<span class="method-type">&laquo;String&raquo;</span> optional custom error message</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds a required validator to this SchemaType. The validator gets added to the front of this SchemaType's validators array using <code>unshift()</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: { type: <span class="hljs-built_in">Date</span>, required: <span class="hljs-literal">true</span> })
-
-<span class="hljs-comment">// or with custom error message</span>
-
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: { type: <span class="hljs-built_in">Date</span>, required: <span class="hljs-string">'{PATH} is required!'</span> })
-
-<span class="hljs-comment">// or with a function</span>
-
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({
-  userId: ObjectId,
-  username: {
-    type: <span class="hljs-built_in">String</span>,
-    required: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.userId != <span class="hljs-literal">null</span>; }
-  }
-})
-
-<span class="hljs-comment">// or with a function and a custom message</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({
-  userId: ObjectId,
-  username: {
-    type: <span class="hljs-built_in">String</span>,
-    required: [
-      <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.userId != <span class="hljs-literal">null</span>; },
-      <span class="hljs-string">'username is required if id is specified'</span>
-    ]
-  }
-})
-
-<span class="hljs-comment">// or through the path API</span>
-
-Schema.path(<span class="hljs-string">'name'</span>).required(<span class="hljs-literal">true</span>);
-
-<span class="hljs-comment">// with custom error messaging</span>
-
-Schema.path(<span class="hljs-string">'name'</span>).required(<span class="hljs-literal">true</span>, <span class="hljs-string">'grrr :( '</span>);
-
-<span class="hljs-comment">// or make a path conditionally required based on a function</span>
-<span class="hljs-keyword">var</span> isOver18 = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.age &gt;= <span class="hljs-number">18</span>; };
-Schema.path(<span class="hljs-string">'voterRegistrationId'</span>).required(isOver18);</code></pre>
-
-<p>The required validator uses the SchemaType's <code>checkRequired</code> function to determine whether a given value satisfies the required validator. By default, a value satisfies the required validator if <code>val != null</code> (that is, if the value is not null nor undefined). However, most built-in mongoose schema types override the default <code>checkRequired</code> function:</p></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-select"><a href="#schematype_SchemaType-select">SchemaType.prototype.select()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Sets default <code>select()</code> behavior for this path.</p>
-
-<p>Set to <code>true</code> if this path should always be included in the results, <code>false</code> if it should be excluded by default. This setting can be overridden at the query level.</p>
-
-<h4>Example:</h4>
-
-<pre><code>T = db.model(<span class="hljs-string">'T'</span>, <span class="hljs-keyword">new</span> Schema({ x: { type: <span class="hljs-built_in">String</span>, select: <span class="hljs-literal">true</span> }}));
-T.find(..); <span class="hljs-comment">// field x will always be selected ..</span>
-<span class="hljs-comment">// .. unless overridden;</span>
-T.find().select(<span class="hljs-string">'-x'</span>).exec(callback);</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-set"><a href="#schematype_SchemaType-set">SchemaType.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds a setter to this schematype.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">capitalize</span> (<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">if</span> (<span class="hljs-keyword">typeof</span> val !== <span class="hljs-string">'string'</span>) val = <span class="hljs-string">''</span>;
-  <span class="hljs-keyword">return</span> val.charAt(<span class="hljs-number">0</span>).toUpperCase() + val.substring(<span class="hljs-number">1</span>);
-}
-
-<span class="hljs-comment">// defining within the schema</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, set: capitalize }});
-
-<span class="hljs-comment">// or with the SchemaType</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> })
-s.path(<span class="hljs-string">'name'</span>).set(capitalize);</code></pre>
-
-<p>Setters allow you to transform the data before it gets to the raw mongodb document or query.</p>
-
-<p>Suppose you are implementing user registration for a website. Users provide an email and password, which gets saved to mongodb. The email is a string that you will want to normalize to lower case, in order to avoid one email having more than one account -- e.g., otherwise, <a href='mailto:avenue@q.com'>avenue@q.com</a> can be registered for 2 accounts via <a href='mailto:avenue@q.com'>avenue@q.com</a> and <a href='mailto:AvEnUe@Q.CoM'>AvEnUe@Q.CoM</a>.</p>
-
-<p>You can set up email lower case normalization easily via a Mongoose setter.</p>
-
-<pre><code>function toLower(v) {
-  return v.toLowerCase();
-}
-
-var UserSchema = new Schema({
-  email: { type: String, set: toLower }
-});
-
-var User = db.model('User', UserSchema);
-
-var user = new User({email: '<a href='mailto:AVENUE@Q.COM'>AVENUE@Q.COM</a>'});
-console.log(user.email); // '<a href='mailto:avenue@q.com'>avenue@q.com</a>'
-
-// or
-var user = new User();
-user.email = '<a href='mailto:Avenue@Q.com'>Avenue@Q.com</a>';
-console.log(user.email); // '<a href='mailto:avenue@q.com'>avenue@q.com</a>'
-User.updateOne({ _id: _id }, { $set: { email: '<a href='mailto:AVENUE@Q.COM'>AVENUE@Q.COM</a>' } }); // update to '<a href='mailto:avenue@q.com'>avenue@q.com</a>'
-</code></pre>
-
-<p>As you can see above, setters allow you to transform the data before it stored in MongoDB, or before executing a query.</p>
-
-<p><em>NOTE: we could have also just used the built-in <code>lowercase: true</code> SchemaType option instead of defining our own function.</em></p>
-
-<pre><code><span class="hljs-keyword">new</span> Schema({ email: { type: <span class="hljs-built_in">String</span>, lowercase: <span class="hljs-literal">true</span> }})</code></pre>
-
-<p>Setters are also passed a second argument, the schematype on which the setter was defined. This allows for tailored behavior based on options passed in the schema.</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">inspector</span> (<span class="hljs-params">val, schematype</span>) </span>{
-  <span class="hljs-keyword">if</span> (schematype.options.required) {
-    <span class="hljs-keyword">return</span> schematype.path + <span class="hljs-string">' is required'</span>;
-  } <span class="hljs-keyword">else</span> {
-    <span class="hljs-keyword">return</span> val;
-  }
-}
-
-<span class="hljs-keyword">var</span> VirusSchema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span>, set: inspector },
-  taxonomy: { type: <span class="hljs-built_in">String</span>, set: inspector }
-})
-
-<span class="hljs-keyword">var</span> Virus = db.model(<span class="hljs-string">'Virus'</span>, VirusSchema);
-<span class="hljs-keyword">var</span> v = <span class="hljs-keyword">new</span> Virus({ name: <span class="hljs-string">'Parvoviridae'</span>, taxonomy: <span class="hljs-string">'Parvovirinae'</span> });
-
-<span class="hljs-built_in">console</span>.log(v.name);     <span class="hljs-comment">// name is required</span>
-<span class="hljs-built_in">console</span>.log(v.taxonomy); <span class="hljs-comment">// Parvovirinae</span></code></pre>
-
-<p>You can also use setters to modify other properties on the document. If you're setting a property <code>name</code> on a document, the setter will run with <code>this</code> as the document. Be careful, in mongoose 5 setters will also run when querying by <code>name</code> with <code>this</code> as the query.</p>
-
-<div class="highlight"><pre lang="javascript">const nameSchema = new Schema({ name: String, keywords: [String] });
-nameSchema.path('name').set(function(v) {
-  // Need to check if `this` is a document, because in mongoose 5
-  // setters will also run on queries, in which case `this` will be a
-  // mongoose query object.
-  if (this instanceof Document && v != null) {
-    this.keywords = v.split(' ');
-  }
-  return v;
-});
-</pre></div></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-sparse"><a href="#schematype_SchemaType-sparse">SchemaType.prototype.sparse()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares a sparse index.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, sparse: <span class="hljs-literal">true</span> } });
-Schema.path(<span class="hljs-string">'name'</span>).index({ sparse: <span class="hljs-literal">true</span> });</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-text"><a href="#schematype_SchemaType-text">SchemaType.prototype.text()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares a full text index.</p>
-
-<h3>Example:</h3>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({name : {type: <span class="hljs-built_in">String</span>, text : <span class="hljs-literal">true</span> })
- Schema.path(<span class="hljs-string">'name'</span>).index({text : <span class="hljs-literal">true</span>});</code></pre></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-unique"><a href="#schematype_SchemaType-unique">SchemaType.prototype.unique()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares an unique index.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, unique: <span class="hljs-literal">true</span> }});
-Schema.path(<span class="hljs-string">'name'</span>).index({ unique: <span class="hljs-literal">true</span> });</code></pre>
-
-<p><em>NOTE: violating the constraint returns an <code>E11000</code> error from MongoDB when saving, not a Mongoose validation error.</em></p></div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-validate"><a href="#schematype_SchemaType-validate">SchemaType.prototype.validate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;RegExp|Function|Object&raquo;</span> validator function, or hash describing options</li><ul style="margin-top: 0.5em"><li>[obj.validator]
-<span class="method-type">&laquo;Function&raquo;</span> validator function. If the validator function returns <code>undefined</code> or a truthy value, validation succeeds. If it returns falsy (except <code>undefined</code>) or throws an error, validation fails.</li></ul><ul style="margin-top: 0.5em"><li>[obj.message]
-<span class="method-type">&laquo;String|Function&raquo;</span> optional error message. If function, should return the error message as a string</li></ul><ul style="margin-top: 0.5em"><li>[obj.propsParameter=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, Mongoose will pass the validator properties object (with the <code>validator</code> function, <code>message</code>, etc.) as the 2nd arg to the validator function. This is disabled by default because many validators <a href="https://github.com/chriso/validator.js#validators">rely on positional args</a>, so turning this on may cause unpredictable behavior in external validators.</li></ul><li class="param">[errorMsg]
-<span class="method-type">&laquo;String|Function&raquo;</span> optional error message. If function, should return the error message as a string</li><li class="param">[type]
-<span class="method-type">&laquo;String&raquo;</span> optional validator type</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds validator(s) for this document path.</p>
-
-<p>Validators always receive the value to validate as their first argument and must return <code>Boolean</code>. Returning <code>false</code> or throwing an error means validation failed.</p>
-
-<p>The error message argument is optional. If not passed, the <a href="#error_messages_MongooseError-messages">default generic error message template</a> will be used.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// make sure every value is equal to "something"</span>
-<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">validator</span> (<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">return</span> val == <span class="hljs-string">'something'</span>;
-}
-<span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, validate: validator }});
-
-<span class="hljs-comment">// with a custom error message</span>
-
-<span class="hljs-keyword">var</span> custom = [validator, <span class="hljs-string">'Uh oh, {PATH} does not equal "something".'</span>]
-<span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, validate: custom }});
-
-<span class="hljs-comment">// adding many validators at a time</span>
-
-<span class="hljs-keyword">var</span> many = [
-    { validator: validator, msg: <span class="hljs-string">'uh oh'</span> }
-  , { validator: anotherValidator, msg: <span class="hljs-string">'failed'</span> }
-]
-<span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, validate: many }});
-
-<span class="hljs-comment">// or utilizing SchemaType methods directly:</span>
-
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-string">'string'</span> });
-schema.path(<span class="hljs-string">'name'</span>).validate(validator, <span class="hljs-string">'validation of `{PATH}` failed with value `{VALUE}`'</span>);</code></pre>
-
-<h4>Error message templates:</h4>
-
-<p>From the examples above, you may have noticed that error messages support basic templating. There are a few other template keywords besides <code>{PATH}</code> and <code>{VALUE}</code> too. To find out more, details are available <a href="#error_messages_MongooseError.messages">here</a>.</p>
-
-<p>If Mongoose's built-in error message templating isn't enough, Mongoose supports setting the <code>message</code> property to a function.</p>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>).validate({
-  validator: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> v.length &gt; <span class="hljs-number">5</span>; },
-  <span class="hljs-comment">// `errors['name']` will be "name must have length 5, got 'foo'"</span>
-  message: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">props</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-string">`<span class="hljs-subst">${props.path}</span> must have length 5, got '<span class="hljs-subst">${props.value}</span>'`</span>;
-  }
-});</code></pre>
-
-<p>To bypass Mongoose's error messages and just copy the error message that the validator throws, do this:</p>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>).validate({
-  validator: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Oops!'</span>); },
-  <span class="hljs-comment">// `errors['name']` will be "Oops!"</span>
-  message: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">props</span>) </span>{ <span class="hljs-keyword">return</span> props.reason.message; }
-});</code></pre>
-
-<h4>Asynchronous validation:</h4>
-
-<p>Mongoose supports validators that return a promise. A validator that returns a promise is called an <em>async validator</em>. Async validators run in parallel, and <code>validate()</code> will wait until all async validators have settled.</p>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>).validate({
-  validator: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">value</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Promise</span>(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">resolve, reject</span>) </span>{
-      resolve(<span class="hljs-literal">false</span>); <span class="hljs-comment">// validation failed</span>
-    });
-  }
-});</code></pre>
-
-<p>You might use asynchronous validators to retreive other documents from the database to validate against or to meet other I/O bound validation needs.</p>
-
-<p>Validation occurs <code>pre('save')</code> or whenever you manually execute <a href="#document_Document-validate">document#validate</a>.</p>
-
-<p>If validation fails during <code>pre('save')</code> and no callback was passed to receive the error, an <code>error</code> event will be emitted on your Models associated db <a href="#connection_Connection">connection</a>, passing the validation error object along.</p>
-
-<pre><code><span class="hljs-keyword">var</span> conn = mongoose.createConnection(..);
-conn.on(<span class="hljs-string">'error'</span>, handleError);
-
-<span class="hljs-keyword">var</span> Product = conn.model(<span class="hljs-string">'Product'</span>, yourSchema);
-<span class="hljs-keyword">var</span> dvd = <span class="hljs-keyword">new</span> Product(..);
-dvd.save(); <span class="hljs-comment">// emits error on the `conn` above</span></code></pre>
-
-<p>If you want to handle these errors at the Model level, add an <code>error</code> listener to your Model as shown below.</p>
-
-<pre><code><span class="hljs-comment">// registering an error listener on the Model lets us handle errors more locally</span>
-Product.on(<span class="hljs-string">'error'</span>, handleError);</code></pre></div><hr class="separate-api"><h2 class="item-header" id="Virtualtype"><a href="#Virtualtype">Virtualtype</a></h2><ul><li><a href="#virtualtype_VirtualType">VirtualType()</a></li><li><a href="#virtualtype_VirtualType-applyGetters">VirtualType.prototype.applyGetters()</a></li><li><a href="#virtualtype_VirtualType-applySetters">VirtualType.prototype.applySetters()</a></li><li><a href="#virtualtype_VirtualType-get">VirtualType.prototype.get()</a></li><li><a href="#virtualtype_VirtualType-set">VirtualType.prototype.set()</a></li></ul><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType"><a href="#virtualtype_VirtualType">VirtualType()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.ref]
-<span class="method-type">&laquo;string|function&raquo;</span> if <code>ref</code> is not nullish, this becomes a <a href="/docs/populate.html#populate-virtuals">populated virtual</a></li></ul><ul style="margin-top: 0.5em"><li>[options.localField]
-<span class="method-type">&laquo;string|function&raquo;</span> the local field to populate on if this is a populated virtual.</li></ul><ul style="margin-top: 0.5em"><li>[options.foreignField]
-<span class="method-type">&laquo;string|function&raquo;</span> the foreign field to populate on if this is a populated virtual.</li></ul><ul style="margin-top: 0.5em"><li>[options.justOne=false]
-<span class="method-type">&laquo;boolean&raquo;</span> by default, a populated virtual is an array. If you set <code>justOne</code>, the populated virtual will be a single doc or <code>null</code>.</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if you set this to <code>true</code>, Mongoose will call any custom getters you defined on this virtual</li></ul><ul style="margin-top: 0.5em"><li>[options.count=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if you set this to <code>true</code>, <code>populate()</code> will set this virtual to the number of populated documents, as opposed to the documents themselves, using <a href="./api.html#query_Query-countDocuments"><code>Query#countDocuments()</code></a></li></ul></ul><div><p>VirtualType constructor</p>
-
-<p>This is what mongoose uses to define virtual attributes via <code>Schema.prototype.virtual</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> fullname = schema.virtual(<span class="hljs-string">'fullname'</span>);
-fullname <span class="hljs-keyword">instanceof</span> mongoose.VirtualType <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-applyGetters"><a href="#virtualtype_VirtualType-applyGetters">VirtualType.prototype.applyGetters()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Document&raquo;</span> The document this virtual is attached to</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;any&raquo;</span> the value after applying all getters</li></ul><div><p>Applies getters to <code>value</code>.</p></div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-applySetters"><a href="#virtualtype_VirtualType-applySetters">VirtualType.prototype.applySetters()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Document&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;any&raquo;</span> the value after applying all setters</li></ul><div><p>Applies setters to <code>value</code>.</p></div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-get"><a href="#virtualtype_VirtualType-get">VirtualType.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">VirtualType,
-<span class="method-type">&laquo;Function(Any|&raquo;</span> Document)} fn</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> this</li></ul><div><p>Adds a custom getter to this virtual.</p>
-
-<h2>Mongoose calls the getter function with 3 parameters</h2>
-
-<ul>
-<li><code>value</code>: the value returned by the previous getter. If there is only one getter, <code>value</code> will be <code>undefined</code>.</li>
-<li><code>virtual</code>: the virtual object you called <code>.get()</code> on</li>
-<li><code>doc</code>: the document this virtual is attached to. Equivalent to <code>this</code>.</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> virtual = schema.virtual(<span class="hljs-string">'fullname'</span>);
-virtual.get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value, virtual, doc</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.name.first + <span class="hljs-string">' '</span> + <span class="hljs-keyword">this</span>.name.last;
-});</code></pre></div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-set"><a href="#virtualtype_VirtualType-set">VirtualType.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">VirtualType,
-<span class="method-type">&laquo;Function(Any|&raquo;</span> Document)} fn</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> this</li></ul><div><p>Adds a custom setter to this virtual.</p>
-
-<h2>Mongoose calls the setter function with 3 parameters</h2>
-
-<ul>
-<li><code>value</code>: the value being set</li>
-<li><code>virtual</code>: the virtual object you're calling <code>.set()</code> on</li>
-<li><code>doc</code>: the document this virtual is attached to. Equivalent to <code>this</code>.</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> virtual = schema.virtual(<span class="hljs-string">'fullname'</span>);
-virtual.set(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value, virtual, doc</span>) </span>{
-  <span class="hljs-keyword">var</span> parts = value.split(<span class="hljs-string">' '</span>);
-  <span class="hljs-keyword">this</span>.name.first = parts[<span class="hljs-number">0</span>];
-  <span class="hljs-keyword">this</span>.name.last = parts[<span class="hljs-number">1</span>];
-});
-
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model();
-<span class="hljs-comment">// Calls the setter with `value = 'Jean-Luc Picard'`</span>
-doc.fullname = <span class="hljs-string">'Jean-Luc Picard'</span>;
-doc.name.first; <span class="hljs-comment">// 'Jean-Luc'</span>
-doc.name.last; <span class="hljs-comment">// 'Picard'</span></code></pre></div><hr class="separate-api"><h2 class="item-header" id="Error"><a href="#Error">Error</a></h2><ul><li><a href="#mongooseerror_MongooseError">Error()</a></li><li><a href="#error_Error-CastError">Error.CastError</a></li><li><a href="#error_Error-DivergentArrayError">Error.DivergentArrayError</a></li><li><a href="#error_Error-DocumentNotFoundError">Error.DocumentNotFoundError</a></li><li><a href="#error_Error-MissingSchemaError">Error.MissingSchemaError</a></li><li><a href="#error_Error-OverwriteModelError">Error.OverwriteModelError</a></li><li><a href="#error_Error-ParallelSaveError">Error.ParallelSaveError</a></li><li><a href="#error_Error-ValidationError">Error.ValidationError</a></li><li><a href="#error_Error-ValidatorError">Error.ValidatorError</a></li><li><a href="#error_Error-VersionError">Error.VersionError</a></li><li><a href="#error_Error-messages">Error.messages</a></li><li><a href="#error_Error-name">Error.prototype.name</a></li></ul><hr class="separate-api-elements"><h3 id="mongooseerror_MongooseError"><a href="#mongooseerror_MongooseError">Error()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">msg
-<span class="method-type">&laquo;String&raquo;</span> Error message</li></ul><div><p>MongooseError constructor. MongooseError is the base class for all Mongoose-specific errors.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ answer: <span class="hljs-built_in">Number</span> }));
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({ answer: <span class="hljs-string">'not a number'</span> });
-<span class="hljs-keyword">const</span> err = doc.validateSync();
-
-err <span class="hljs-keyword">instanceof</span> mongoose.Error; <span class="hljs-comment">// true</span></code></pre></div><hr class="separate-api-elements"><h3 id="error_Error-CastError"><a href="#error_Error-CastError">Error.CastError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when mongoose failed to cast a value.</p></div><hr class="separate-api-elements"><h3 id="error_Error-DivergentArrayError"><a href="#error_Error-DivergentArrayError">Error.DivergentArrayError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error will be returned if you used an array projection and then modified the array in an unsafe way.</p></div><hr class="separate-api-elements"><h3 id="error_Error-DocumentNotFoundError"><a href="#error_Error-DocumentNotFoundError">Error.DocumentNotFoundError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when <code>save()</code> fails because the underlying document was not found. The constructor takes one parameter, the conditions that mongoose passed to <code>update()</code> when trying to update the document.</p></div><hr class="separate-api-elements"><h3 id="error_Error-MissingSchemaError"><a href="#error_Error-MissingSchemaError">Error.MissingSchemaError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Thrown when you try to access a model that has not been registered yet</p></div><hr class="separate-api-elements"><h3 id="error_Error-OverwriteModelError"><a href="#error_Error-OverwriteModelError">Error.OverwriteModelError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Thrown when a model with the given name was already registered on the connection. See <a href="/docs/faq.html#overwrite-model-error">the FAQ about <code>OverwriteModelError</code></a>.</p></div><hr class="separate-api-elements"><h3 id="error_Error-ParallelSaveError"><a href="#error_Error-ParallelSaveError">Error.ParallelSaveError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when you call <code>save()</code> multiple times on the same document in parallel. See the <a href="/docs/faq.html">FAQ</a> for more information.</p></div><hr class="separate-api-elements"><h3 id="error_Error-ValidationError"><a href="#error_Error-ValidationError">Error.ValidationError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when <a href="/docs/validation.html">validation</a> failed. The <code>errors</code> property contains an object whose keys are the paths that failed and whose values are instances of CastError or ValidationError.</p></div><hr class="separate-api-elements"><h3 id="error_Error-ValidatorError"><a href="#error_Error-ValidatorError">Error.ValidatorError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>A <code>ValidationError</code> has a hash of <code>errors</code> that contain individual <code>ValidatorError</code> instances</p></div><hr class="separate-api-elements"><h3 id="error_Error-VersionError"><a href="#error_Error-VersionError">Error.VersionError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when you call <code>save()</code> after the document in the database was changed in a potentially unsafe way. See the <a href="/docs/guide.html#versionKey"><code>versionKey</code> option</a> for more information.</p></div><hr class="separate-api-elements"><h3 id="error_Error-messages"><a href="#error_Error-messages">Error.messages</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The default built-in validator error messages.</p></div><hr class="separate-api-elements"><h3 id="error_Error-name"><a href="#error_Error-name">Error.prototype.name</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;String&raquo;</span></li></ul><div><p>The name of the error. The name uniquely identifies this Mongoose error. The possible values are:</p>
-
-<ul>
-<li><code>MongooseError</code>: general Mongoose error</li>
-<li><code>CastError</code>: Mongoose could not convert a value to the type defined in the schema path. May be in a <code>ValidationError</code> class' <code>errors</code> property.</li>
-<li><code>DisconnectedError</code>: This <a href="connections.html">connection</a> timed out in trying to reconnect to MongoDB and will not successfully reconnect to MongoDB unless you explicitly reconnect.</li>
-<li><code>DivergentArrayError</code>: You attempted to <code>save()</code> an array that was modified after you loaded it with a <code>$elemMatch</code> or similar projection</li>
-<li><code>MissingSchemaError</code>: You tried to access a model with <a href="api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> that was not defined</li>
-<li><code>DocumentNotFoundError</code>: The document you tried to <a href="api.html#document_Document-save"><code>save()</code></a> was not found</li>
-<li><code>ValidatorError</code>: error from an individual schema path's validator</li>
-<li><code>ValidationError</code>: error returned from <a href="api.html#document_Document-validate"><code>validate()</code></a> or <a href="api.html#document_Document-validateSync"><code>validateSync()</code></a>. Contains zero or more <code>ValidatorError</code> instances in <code>.errors</code> property.</li>
-<li><code>MissingSchemaError</code>: You called <code>mongoose.Document()</code> without a schema</li>
-<li><code>ObjectExpectedError</code>: Thrown when you set a nested path to a non-object value with <a href="guide.html#strict">strict mode set</a>.</li>
-<li><code>ObjectParameterError</code>: Thrown when you pass a non-object value to a function which expects an object as a paramter</li>
-<li><code>OverwriteModelError</code>: Thrown when you call <a href="api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> to re-define a model that was already defined.</li>
-<li><code>ParallelSaveError</code>: Thrown when you call <a href="api.html#model_Model-save"><code>save()</code></a> on a document when the same document instance is already saving.</li>
-<li><code>StrictModeError</code>: Thrown when you set a path that isn't the schema and <a href="guide.html#strict">strict mode</a> is set to <code>throw</code>.</li>
-<li><code>VersionError</code>: Thrown when the <a href="guide.html#versionKey">document is out of sync</a></li>
-</ul></div><hr class="separate-api"><h2 class="item-header" id="Array"><a href="#Array">Array</a></h2><ul></ul><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script><script type="text/javascript">var headers = document.querySelectorAll('.item-header');
-var navItems = document.querySelectorAll('.nav-item .nav-item-title');
-var navSubs = document.querySelectorAll('.nav-item-sub');
-var cur = '';
-window.addEventListener('scroll', function() {
-  var scrollY = window.scrollY;
-  var highlight = headers[0];
-  for (var i = 0; i < headers.length; ++i) {
-    if (headers[i].offsetTop > scrollY) {
-      break;
-    }
-    highlight = headers[i];
-  }
-  if (highlight.id !== cur) {
-    cur = highlight.id;
-    for (var j = 0; j < navItems.length; ++j) {
-      navItems[j].style.fontWeight = '';
-    }
-    for (j = 0; j < navSubs.length; ++j) {
-      navSubs[j].style.display = 'none';
-    }
-    document.querySelector('#nav-' + highlight.id + ' .nav-item-title').style.fontWeight = 'bold';
-    document.querySelector('#nav-' + highlight.id + ' .nav-item-sub').style.display = 'block';
-  }
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/aggregate.html b/docs/api/aggregate.html
deleted file mode 100644
index b53ec2c853f..00000000000
--- a/docs/api/aggregate.html
+++ /dev/null
@@ -1,388 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Aggregate</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title" style="font-weight: bold"><a href="aggregate.html">Aggregate</a></div><ul class="nav-item-sub"><li><a href="#aggregate_Aggregate">Aggregate()</a></li><li><a href="#aggregate_Aggregate-Symbol.asyncIterator">Aggregate.prototype.Symbol.asyncIterator()</a></li><li><a href="#aggregate_Aggregate-addCursorFlag">Aggregate.prototype.addCursorFlag</a></li><li><a href="#aggregate_Aggregate-addFields">Aggregate.prototype.addFields()</a></li><li><a href="#aggregate_Aggregate-allowDiskUse">Aggregate.prototype.allowDiskUse()</a></li><li><a href="#aggregate_Aggregate-append">Aggregate.prototype.append()</a></li><li><a href="#aggregate_Aggregate-catch">Aggregate.prototype.catch()</a></li><li><a href="#aggregate_Aggregate-collation">Aggregate.prototype.collation()</a></li><li><a href="#aggregate_Aggregate-count">Aggregate.prototype.count()</a></li><li><a href="#aggregate_Aggregate-cursor">Aggregate.prototype.cursor()</a></li><li><a href="#aggregate_Aggregate-exec">Aggregate.prototype.exec()</a></li><li><a href="#aggregate_Aggregate-explain">Aggregate.prototype.explain()</a></li><li><a href="#aggregate_Aggregate-facet">Aggregate.prototype.facet()</a></li><li><a href="#aggregate_Aggregate-graphLookup">Aggregate.prototype.graphLookup()</a></li><li><a href="#aggregate_Aggregate-group">Aggregate.prototype.group()</a></li><li><a href="#aggregate_Aggregate-hint">Aggregate.prototype.hint()</a></li><li><a href="#aggregate_Aggregate-limit">Aggregate.prototype.limit()</a></li><li><a href="#aggregate_Aggregate-lookup">Aggregate.prototype.lookup()</a></li><li><a href="#aggregate_Aggregate-match">Aggregate.prototype.match()</a></li><li><a href="#aggregate_Aggregate-model">Aggregate.prototype.model()</a></li><li><a href="#aggregate_Aggregate-near">Aggregate.prototype.near()</a></li><li><a href="#aggregate_Aggregate-option">Aggregate.prototype.option()</a></li><li><a href="#aggregate_Aggregate-options">Aggregate.prototype.options</a></li><li><a href="#aggregate_Aggregate-pipeline">Aggregate.prototype.pipeline()</a></li><li><a href="#aggregate_Aggregate-project">Aggregate.prototype.project()</a></li><li><a href="#aggregate_Aggregate-read">Aggregate.prototype.read()</a></li><li><a href="#aggregate_Aggregate-readConcern">Aggregate.prototype.readConcern()</a></li><li><a href="#aggregate_Aggregate-redact">Aggregate.prototype.redact()</a></li><li><a href="#aggregate_Aggregate-replaceRoot">Aggregate.prototype.replaceRoot()</a></li><li><a href="#aggregate_Aggregate-sample">Aggregate.prototype.sample()</a></li><li><a href="#aggregate_Aggregate-session">Aggregate.prototype.session()</a></li><li><a href="#aggregate_Aggregate-skip">Aggregate.prototype.skip()</a></li><li><a href="#aggregate_Aggregate-sort">Aggregate.prototype.sort()</a></li><li><a href="#aggregate_Aggregate-sortByCount">Aggregate.prototype.sortByCount()</a></li><li><a href="#aggregate_Aggregate-then">Aggregate.prototype.then()</a></li><li><a href="#aggregate_Aggregate-unwind">Aggregate.prototype.unwind()</a></li></ul></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#aggregate_Aggregate">Aggregate()</a></li><li><a href="#aggregate_Aggregate-Symbol.asyncIterator">Aggregate.prototype.Symbol.asyncIterator()</a></li><li><a href="#aggregate_Aggregate-addCursorFlag">Aggregate.prototype.addCursorFlag</a></li><li><a href="#aggregate_Aggregate-addFields">Aggregate.prototype.addFields()</a></li><li><a href="#aggregate_Aggregate-allowDiskUse">Aggregate.prototype.allowDiskUse()</a></li><li><a href="#aggregate_Aggregate-append">Aggregate.prototype.append()</a></li><li><a href="#aggregate_Aggregate-catch">Aggregate.prototype.catch()</a></li><li><a href="#aggregate_Aggregate-collation">Aggregate.prototype.collation()</a></li><li><a href="#aggregate_Aggregate-count">Aggregate.prototype.count()</a></li><li><a href="#aggregate_Aggregate-cursor">Aggregate.prototype.cursor()</a></li><li><a href="#aggregate_Aggregate-exec">Aggregate.prototype.exec()</a></li><li><a href="#aggregate_Aggregate-explain">Aggregate.prototype.explain()</a></li><li><a href="#aggregate_Aggregate-facet">Aggregate.prototype.facet()</a></li><li><a href="#aggregate_Aggregate-graphLookup">Aggregate.prototype.graphLookup()</a></li><li><a href="#aggregate_Aggregate-group">Aggregate.prototype.group()</a></li><li><a href="#aggregate_Aggregate-hint">Aggregate.prototype.hint()</a></li><li><a href="#aggregate_Aggregate-limit">Aggregate.prototype.limit()</a></li><li><a href="#aggregate_Aggregate-lookup">Aggregate.prototype.lookup()</a></li><li><a href="#aggregate_Aggregate-match">Aggregate.prototype.match()</a></li><li><a href="#aggregate_Aggregate-model">Aggregate.prototype.model()</a></li><li><a href="#aggregate_Aggregate-near">Aggregate.prototype.near()</a></li><li><a href="#aggregate_Aggregate-option">Aggregate.prototype.option()</a></li><li><a href="#aggregate_Aggregate-options">Aggregate.prototype.options</a></li><li><a href="#aggregate_Aggregate-pipeline">Aggregate.prototype.pipeline()</a></li><li><a href="#aggregate_Aggregate-project">Aggregate.prototype.project()</a></li><li><a href="#aggregate_Aggregate-read">Aggregate.prototype.read()</a></li><li><a href="#aggregate_Aggregate-readConcern">Aggregate.prototype.readConcern()</a></li><li><a href="#aggregate_Aggregate-redact">Aggregate.prototype.redact()</a></li><li><a href="#aggregate_Aggregate-replaceRoot">Aggregate.prototype.replaceRoot()</a></li><li><a href="#aggregate_Aggregate-sample">Aggregate.prototype.sample()</a></li><li><a href="#aggregate_Aggregate-session">Aggregate.prototype.session()</a></li><li><a href="#aggregate_Aggregate-skip">Aggregate.prototype.skip()</a></li><li><a href="#aggregate_Aggregate-sort">Aggregate.prototype.sort()</a></li><li><a href="#aggregate_Aggregate-sortByCount">Aggregate.prototype.sortByCount()</a></li><li><a href="#aggregate_Aggregate-then">Aggregate.prototype.then()</a></li><li><a href="#aggregate_Aggregate-unwind">Aggregate.prototype.unwind()</a></li></ul><hr class="separate-api-elements"><h3 id="aggregate_Aggregate"><a href="#aggregate_Aggregate">Aggregate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[pipeline]
-<span class="method-type">&laquo;Array&raquo;</span> aggregation pipeline as an array of objects</li></ul><div><p>Aggregate constructor used for building aggregation pipelines. Do not instantiate this class directly, use <a href="/docs/api.html#model_Model.aggregate">Model.aggregate()</a> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> aggregate = Model.aggregate([
-  { $project: { a: <span class="hljs-number">1</span>, b: <span class="hljs-number">1</span> } },
-  { $skip: <span class="hljs-number">5</span> }
-]);
-
-Model.
-  aggregate([{ $match: { age: { $gte: <span class="hljs-number">21</span> }}}]).
-  unwind(<span class="hljs-string">'tags'</span>).
-  exec(callback);</code></pre>
-
-<h4>Note:</h4>
-
-<ul>
-<li>The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).</li>
-<li>Mongoose does <strong>not</strong> cast pipeline stages. The below will <strong>not</strong> work unless <code>_id</code> is a string in the database</li>
-</ul>
-
-<div class="highlight"><pre lang="javascript">  new Aggregate([{ $match: { _id: '00000000000000000000000a' } }]);
-  // Do this instead to cast to an ObjectId
-  new Aggregate([{ $match: { _id: mongoose.Types.ObjectId('00000000000000000000000a') } }]);
-</pre></div>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-Symbol.asyncIterator"><a href="#aggregate_Aggregate-Symbol.asyncIterator">Aggregate.prototype.Symbol.asyncIterator()</a></h3><div><p>Returns an asyncIterator for use with <a href="http://bit.ly/async-iterators"><code>for/await/of</code> loops</a> This function <em>only</em> works for <code>find()</code> queries. You do not need to call this function explicitly, the JavaScript runtime will call it for you.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> doc <span class="hljs-keyword">of</span> Model.find().sort({ name: <span class="hljs-number">1</span> })) {
-  <span class="hljs-built_in">console</span>.log(doc.name);
-}</code></pre>
-
-<p>Node.js 10.x supports async iterators natively without any flags. You can enable async iterators in Node.js 8.x using the <a href="https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187"><code>--harmony_async_iteration</code> flag</a>.</p>
-
-<p><strong>Note:</strong> This function is not if <code>Symbol.asyncIterator</code> is undefined. If <code>Symbol.asyncIterator</code> is undefined, that means your Node.js version does not support async iterators.</p>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-addCursorFlag"><a href="#aggregate_Aggregate-addCursorFlag">Aggregate.prototype.addCursorFlag</a></h3><h5>Parameters</h5><ul class="params"><li class="param">flag
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Sets an option on this aggregation. This function will be deprecated in a future release. Use the <a href="./api.html#aggregate_Aggregate-cursor"><code>cursor()</code></a>, <a href="./api.html#aggregate_Aggregate-collation"><code>collation()</code></a>, etc. helpers to set individual options, or access <code>agg.options</code> directly.</p>
-
-<p>Note that MongoDB aggregations <a href="https://jira.mongodb.org/browse/SERVER-6036">do <strong>not</strong> support the <code>noCursorTimeout</code> flag</a>, if you try setting that flag with this function you will get a "unrecognized field 'noCursorTimeout'" error.</p>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-addFields"><a href="#aggregate_Aggregate-addFields">Aggregate.prototype.addFields()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> field specification</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $addFields operator to this aggregate pipeline. Requires MongoDB v3.4+ to work</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// adding new fields based on existing fields</span>
-aggregate.addFields({
-    newField: <span class="hljs-string">'$b.nested'</span>
-  , plusTen: { $add: [<span class="hljs-string">'$val'</span>, <span class="hljs-number">10</span>]}
-  , sub: {
-       name: <span class="hljs-string">'$a'</span>
-    }
-})
-
-<span class="hljs-comment">// etc</span>
-aggregate.addFields({ salary_k: { $divide: [ <span class="hljs-string">"$salary"</span>, <span class="hljs-number">1000</span> ] } });</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-allowDiskUse"><a href="#aggregate_Aggregate-allowDiskUse">Aggregate.prototype.allowDiskUse()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> Should tell server it can use hard drive to store data during aggregation.</li><li class="param">[tags]
-<span class="method-type">&laquo;Array&raquo;</span> optional tags for this query</li></ul><div><p>Sets the allowDiskUse option for the aggregation query (ignored for &lt; 2.6.0)</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> Model.aggregate([{ $match: { foo: <span class="hljs-string">'bar'</span> } }]).allowDiskUse(<span class="hljs-literal">true</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-append"><a href="#aggregate_Aggregate-append">Aggregate.prototype.append()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ops
-<span class="method-type">&laquo;Object&raquo;</span> operator(s) to append</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new operators to this aggregate pipeline</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.append({ $project: { field: <span class="hljs-number">1</span> }}, { $limit: <span class="hljs-number">2</span> });
-
-<span class="hljs-comment">// or pass an array</span>
-<span class="hljs-keyword">var</span> pipeline = [{ $match: { daw: <span class="hljs-string">'Logic Audio X'</span> }} ];
-aggregate.append(pipeline);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-catch"><a href="#aggregate_Aggregate-catch">Aggregate.prototype.catch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query returning a <code>Promise</code> which will be resolved with either the doc(s) or rejected with the error. Like <a href="#query_Query-then"><code>.then()</code></a>, but only takes a rejection handler.</p>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-collation"><a href="#aggregate_Aggregate-collation">Aggregate.prototype.collation()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">collation
-<span class="method-type">&laquo;Object&raquo;</span> options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Adds a collation</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).collation({ locale: <span class="hljs-string">'en_US'</span>, strength: <span class="hljs-number">1</span> }).exec();</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-count"><a href="#aggregate_Aggregate-count">Aggregate.prototype.count()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">the
-<span class="method-type">&laquo;String&raquo;</span> name of the count field</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $count operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.count(<span class="hljs-string">"userCount"</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-cursor"><a href="#aggregate_Aggregate-cursor">Aggregate.prototype.cursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options.batchSize
-<span class="method-type">&laquo;Number&raquo;</span> set the cursor batch size</li><ul style="margin-top: 0.5em"><li>[options.useMongooseAggCursor]
-<span class="method-type">&laquo;Boolean&raquo;</span> use experimental mongoose-specific aggregation cursor (for <code>eachAsync()</code> and other query cursor semantics)</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Sets the cursor option option for the aggregation query (ignored for &lt; 2.6.0). Note the different syntax below: .exec() returns a cursor object, and no callback is necessary.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> cursor = Model.aggregate(..).cursor({ batchSize: <span class="hljs-number">1000</span> }).exec();
-cursor.eachAsync(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// use doc</span>
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-exec"><a href="#aggregate_Aggregate-exec">Aggregate.prototype.exec()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the aggregate pipeline on the currently bound Model.</p>
-
-<h4>Example:</h4>
-
-<pre><code>aggregate.exec(callback);
-
-<span class="hljs-comment">// Because a promise is returned, the `callback` is optional.</span>
-<span class="hljs-keyword">var</span> promise = aggregate.exec();
-promise.then(..);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-explain"><a href="#aggregate_Aggregate-explain">Aggregate.prototype.explain()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute the aggregation with explain</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).explain(callback)</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-facet"><a href="#aggregate_Aggregate-facet">Aggregate.prototype.facet()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">facet
-<span class="method-type">&laquo;Object&raquo;</span> options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Combines multiple aggregation pipelines.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(...)
- .facet({
-   books: [{ groupBy: <span class="hljs-string">'$author'</span> }],
-   price: [{ $bucketAuto: { groupBy: <span class="hljs-string">'$price'</span>, buckets: <span class="hljs-number">2</span> } }]
- })
- .exec();
-
-<span class="hljs-comment">// Output: { books: [...], price: [{...}, {...}] }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-graphLookup"><a href="#aggregate_Aggregate-graphLookup">Aggregate.prototype.graphLookup()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> to $graphLookup as described in the above link</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $graphLookup operator(s) to this aggregate pipeline, performing a recursive search on a collection.</p>
-
-<p>Note that graphLookup can only consume at most 100MB of memory, and does not allow disk use even if <code>{ allowDiskUse: true }</code> is specified.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// Suppose we have a collection of courses, where a document might look like `{ _id: 0, name: 'Calculus', prerequisite: 'Trigonometry'}` and `{ _id: 0, name: 'Trigonometry', prerequisite: 'Algebra' }`</span>
- aggregate.graphLookup({ <span class="hljs-keyword">from</span>: <span class="hljs-string">'courses'</span>, startWith: <span class="hljs-string">'$prerequisite'</span>, connectFromField: <span class="hljs-string">'prerequisite'</span>, connectToField: <span class="hljs-string">'name'</span>, <span class="hljs-keyword">as</span>: <span class="hljs-string">'prerequisites'</span>, maxDepth: <span class="hljs-number">3</span> }) <span class="hljs-comment">// this will recursively search the 'courses' collection up to 3 prerequisites</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-group"><a href="#aggregate_Aggregate-group">Aggregate.prototype.group()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> $group operator contents</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new custom $group operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.group({ _id: <span class="hljs-string">"$department"</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-hint"><a href="#aggregate_Aggregate-hint">Aggregate.prototype.hint()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object|String&raquo;</span> a hint object or the index name</li></ul><div><p>Sets the hint option for the aggregation query (ignored for &lt; 3.6.0)</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).hint({ qty: <span class="hljs-number">1</span>, category: <span class="hljs-number">1</span> }).exec(callback)</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-limit"><a href="#aggregate_Aggregate-limit">Aggregate.prototype.limit()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">num
-<span class="method-type">&laquo;Number&raquo;</span> maximum number of records to pass to the next stage</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $limit operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.limit(<span class="hljs-number">10</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-lookup"><a href="#aggregate_Aggregate-lookup">Aggregate.prototype.lookup()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> to $lookup as described in the above link</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $lookup operator(s) to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.lookup({ <span class="hljs-keyword">from</span>: <span class="hljs-string">'users'</span>, localField: <span class="hljs-string">'userId'</span>, foreignField: <span class="hljs-string">'_id'</span>, <span class="hljs-keyword">as</span>: <span class="hljs-string">'users'</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-match"><a href="#aggregate_Aggregate-match">Aggregate.prototype.match()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> $match operator contents</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new custom $match operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.match({ department: { $<span class="hljs-keyword">in</span>: [ <span class="hljs-string">"sales"</span>, <span class="hljs-string">"engineering"</span> ] } });</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-model"><a href="#aggregate_Aggregate-model">Aggregate.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[model]
-<span class="method-type">&laquo;Model&raquo;</span> the model to which the aggregate is to be bound</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate,Model&raquo;</span> if model is passed, will return <code>this</code>, otherwise will return the model</li></ul><div><p>Get/set the model that this aggregation will execute on.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> aggregate = MyModel.aggregate([{ $match: { answer: <span class="hljs-number">42</span> } }]);
-aggregate.model() === MyModel; <span class="hljs-comment">// true</span>
-
-<span class="hljs-comment">// Change the model. There's rarely any reason to do this.</span>
-aggregate.model(SomeOtherModel);
-aggregate.model() === SomeOtherModel; <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-near"><a href="#aggregate_Aggregate-near">Aggregate.prototype.near()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $geoNear operator to this aggregate pipeline.</p>
-
-<h4>NOTE:</h4>
-
-<p><strong>MUST</strong> be used as the first operator in the pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.near({
-  near: [<span class="hljs-number">40.724</span>, <span class="hljs-number">-73.997</span>],
-  distanceField: <span class="hljs-string">"dist.calculated"</span>, <span class="hljs-comment">// required</span>
-  maxDistance: <span class="hljs-number">0.008</span>,
-  query: { type: <span class="hljs-string">"public"</span> },
-  includeLocs: <span class="hljs-string">"dist.location"</span>,
-  uniqueDocs: <span class="hljs-literal">true</span>,
-  num: <span class="hljs-number">5</span>
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-option"><a href="#aggregate_Aggregate-option">Aggregate.prototype.option()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> keys to merge into current options</li><li class="param">number
-<span class="method-type">&laquo;[options.maxTimeMS]&raquo;</span> limits the time this aggregation will run, see <a href="https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/">MongoDB docs on <code>maxTimeMS</code></a></li><li class="param">boolean
-<span class="method-type">&laquo;[options.allowDiskUse]&raquo;</span> if true, the MongoDB server will use the hard drive to store data during this aggregation</li><li class="param">object
-<span class="method-type">&laquo;[options.collation]&raquo;</span> see <a href="./docs/api.html#aggregate_Aggregate-collation"><code>Aggregate.prototype.collation()</code></a></li><li class="param">ClientSession
-<span class="method-type">&laquo;[options.session]&raquo;</span> see <a href="./docs/api.html#aggregate_Aggregate-session"><code>Aggregate.prototype.session()</code></a></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Lets you set arbitrary options, for middleware or plugins.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> agg = Model.aggregate(..).option({ allowDiskUse: <span class="hljs-literal">true</span> }); <span class="hljs-comment">// Set the `allowDiskUse` option</span>
-agg.options; <span class="hljs-comment">// `{ allowDiskUse: true }`</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-options"><a href="#aggregate_Aggregate-options">Aggregate.prototype.options</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Contains options passed down to the <a href="https://docs.mongodb.com/manual/reference/command/aggregate/">aggregate command</a>.</p>
-
-<h2>Supported options are</h2>
-
-<ul>
-<li><code>readPreference</code></li>
-<li><a href="./api.html#aggregate_Aggregate-cursor"><code>cursor</code></a></li>
-<li><a href="./api.html#aggregate_Aggregate-explain"><code>explain</code></a></li>
-<li><a href="./api.html#aggregate_Aggregate-allowDiskUse"><code>allowDiskUse</code></a></li>
-<li><code>maxTimeMS</code></li>
-<li><code>bypassDocumentValidation</code></li>
-<li><code>raw</code></li>
-<li><code>promoteLongs</code></li>
-<li><code>promoteValues</code></li>
-<li><code>promoteBuffers</code></li>
-<li><a href="./api.html#aggregate_Aggregate-collation"><code>collation</code></a></li>
-<li><code>comment</code></li>
-<li><a href="./api.html#aggregate_Aggregate-session"><code>session</code></a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-pipeline"><a href="#aggregate_Aggregate-pipeline">Aggregate.prototype.pipeline()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns the current pipeline</p>
-
-<h4>Example:</h4>
-
-<pre><code>MyModel.aggregate().match({ test: <span class="hljs-number">1</span> }).pipeline(); <span class="hljs-comment">// [{ $match: { test: 1 } }]</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-project"><a href="#aggregate_Aggregate-project">Aggregate.prototype.project()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> field specification</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $project operator to this aggregate pipeline.</p>
-
-<p>Mongoose query <a href="#query_Query-select">selection syntax</a> is also supported.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// include a, include b, exclude _id</span>
-aggregate.project(<span class="hljs-string">"a b -_id"</span>);
-
-<span class="hljs-comment">// or you may use object notation, useful when</span>
-<span class="hljs-comment">// you have keys already prefixed with a "-"</span>
-aggregate.project({a: <span class="hljs-number">1</span>, b: <span class="hljs-number">1</span>, _id: <span class="hljs-number">0</span>});
-
-<span class="hljs-comment">// reshaping documents</span>
-aggregate.project({
-    newField: <span class="hljs-string">'$b.nested'</span>
-  , plusTen: { $add: [<span class="hljs-string">'$val'</span>, <span class="hljs-number">10</span>]}
-  , sub: {
-       name: <span class="hljs-string">'$a'</span>
-    }
-})
-
-<span class="hljs-comment">// etc</span>
-aggregate.project({ salary_k: { $divide: [ <span class="hljs-string">"$salary"</span>, <span class="hljs-number">1000</span> ] } });</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-read"><a href="#aggregate_Aggregate-read">Aggregate.prototype.read()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">pref
-<span class="method-type">&laquo;String&raquo;</span> one of the listed preference options or their aliases</li><li class="param">[tags]
-<span class="method-type">&laquo;Array&raquo;</span> optional tags for this query</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Sets the readPreference option for the aggregation query.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).read(<span class="hljs-string">'primaryPreferred'</span>).exec(callback)</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-readConcern"><a href="#aggregate_Aggregate-readConcern">Aggregate.prototype.readConcern()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">level
-<span class="method-type">&laquo;String&raquo;</span> one of the listed read concern level or their aliases</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Sets the readConcern level for the aggregation query.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).readConcern(<span class="hljs-string">'majority'</span>).exec(callback)</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-redact"><a href="#aggregate_Aggregate-redact">Aggregate.prototype.redact()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">expression
-<span class="method-type">&laquo;Object&raquo;</span> redact options or conditional expression</li><li class="param">[thenExpr]
-<span class="method-type">&laquo;String|Object&raquo;</span> true case for the condition</li><li class="param">[elseExpr]
-<span class="method-type">&laquo;String|Object&raquo;</span> false case for the condition</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Appends a new $redact operator to this aggregate pipeline.</p>
-
-<p>If 3 arguments are supplied, Mongoose will wrap them with if-then-else of $cond operator respectively If <code>thenExpr</code> or <code>elseExpr</code> is string, make sure it starts with $$, like <code>$$DESCEND</code>, <code>$$PRUNE</code> or <code>$$KEEP</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(...)
- .redact({
-   $cond: {
-     <span class="hljs-keyword">if</span>: { $eq: [ <span class="hljs-string">'$level'</span>, <span class="hljs-number">5</span> ] },
-     then: <span class="hljs-string">'$$PRUNE'</span>,
-     <span class="hljs-keyword">else</span>: <span class="hljs-string">'$$DESCEND'</span>
-   }
- })
- .exec();
-
-<span class="hljs-comment">// $redact often comes with $cond operator, you can also use the following syntax provided by mongoose</span>
-Model.aggregate(...)
- .redact({ $eq: [ <span class="hljs-string">'$level'</span>, <span class="hljs-number">5</span> ] }, <span class="hljs-string">'$$PRUNE'</span>, <span class="hljs-string">'$$DESCEND'</span>)
- .exec();</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-replaceRoot"><a href="#aggregate_Aggregate-replaceRoot">Aggregate.prototype.replaceRoot()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">the
-<span class="method-type">&laquo;String|Object&raquo;</span> field or document which will become the new root document</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $replaceRoot operator to this aggregate pipeline.</p>
-
-<p>Note that the <code>$replaceRoot</code> operator requires field strings to start with '$'. If you are passing in a string Mongoose will prepend '$' if the specified field doesn't start '$'. If you are passing in an object the strings in your expression will not be altered.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.replaceRoot(<span class="hljs-string">"user"</span>);
-
-aggregate.replaceRoot({ x: { $concat: [<span class="hljs-string">'$this'</span>, <span class="hljs-string">'$that'</span>] } });</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-sample"><a href="#aggregate_Aggregate-sample">Aggregate.prototype.sample()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">size
-<span class="method-type">&laquo;Number&raquo;</span> number of random documents to pick</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $sample operator(s) to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.sample(<span class="hljs-number">3</span>); <span class="hljs-comment">// Add a pipeline that picks 3 random documents</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-session"><a href="#aggregate_Aggregate-session">Aggregate.prototype.session()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">session
-<span class="method-type">&laquo;ClientSession&raquo;</span> </li></ul><div><p>Sets the session for this aggregation. Useful for <a href="/docs/transactions.html">transactions</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = <span class="hljs-keyword">await</span> Model.startSession();
-<span class="hljs-keyword">await</span> Model.aggregate(..).session(session);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-skip"><a href="#aggregate_Aggregate-skip">Aggregate.prototype.skip()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">num
-<span class="method-type">&laquo;Number&raquo;</span> number of records to skip before next stage</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends a new $skip operator to this aggregate pipeline.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.skip(<span class="hljs-number">10</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-sort"><a href="#aggregate_Aggregate-sort">Aggregate.prototype.sort()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Appends a new $sort operator to this aggregate pipeline.</p>
-
-<p>If an object is passed, values allowed are <code>asc</code>, <code>desc</code>, <code>ascending</code>, <code>descending</code>, <code>1</code>, and <code>-1</code>.</p>
-
-<p>If a string is passed, it must be a space delimited list of path names. The sort order of each path is ascending unless the path name is prefixed with <code>-</code> which will be treated as descending.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// these are equivalent</span>
-aggregate.sort({ field: <span class="hljs-string">'asc'</span>, test: <span class="hljs-number">-1</span> });
-aggregate.sort(<span class="hljs-string">'field -test'</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-sortByCount"><a href="#aggregate_Aggregate-sortByCount">Aggregate.prototype.sortByCount()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> this</li></ul><div><p>Appends a new $sortByCount operator to this aggregate pipeline. Accepts either a string field name or a pipeline object.</p>
-
-<p>Note that the <code>$sortByCount</code> operator requires the new root to start with '$'. Mongoose will prepend '$' if the specified field name doesn't start with '$'.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.sortByCount(<span class="hljs-string">'users'</span>);
-aggregate.sortByCount({ $mergeObjects: [ <span class="hljs-string">"$employee"</span>, <span class="hljs-string">"$business"</span> ] })</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-then"><a href="#aggregate_Aggregate-then">Aggregate.prototype.then()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[resolve]
-<span class="method-type">&laquo;Function&raquo;</span> successCallback</li><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> errorCallback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Provides promise for aggregate.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.aggregate(..).then(successCallback, errorCallback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregate_Aggregate-unwind"><a href="#aggregate_Aggregate-unwind">Aggregate.prototype.unwind()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fields
-<span class="method-type">&laquo;String&raquo;</span> the field(s) to unwind</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Appends new custom $unwind operator(s) to this aggregate pipeline.</p>
-
-<p>Note that the <code>$unwind</code> operator requires the path name to start with '$'. Mongoose will prepend '$' if the specified field doesn't start '$'.</p>
-
-<h4>Examples:</h4>
-
-<pre><code>aggregate.unwind(<span class="hljs-string">"tags"</span>);
-aggregate.unwind(<span class="hljs-string">"a"</span>, <span class="hljs-string">"b"</span>, <span class="hljs-string">"c"</span>);</code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/aggregationcursor.html b/docs/api/aggregationcursor.html
deleted file mode 100644
index 4f39cdc6beb..00000000000
--- a/docs/api/aggregationcursor.html
+++ /dev/null
@@ -1,105 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>AggregationCursor</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title" style="font-weight: bold"><a href="aggregationcursor.html">AggregationCursor</a></div><ul class="nav-item-sub"><li><a href="#aggregationcursor_AggregationCursor">AggregationCursor()</a></li><li><a href="#aggregationcursor_AggregationCursor-addCursorFlag">AggregationCursor.prototype.addCursorFlag()</a></li><li><a href="#aggregationcursor_AggregationCursor-close">AggregationCursor.prototype.close()</a></li><li><a href="#aggregationcursor_AggregationCursor-eachAsync">AggregationCursor.prototype.eachAsync()</a></li><li><a href="#aggregationcursor_AggregationCursor-map">AggregationCursor.prototype.map()</a></li><li><a href="#aggregationcursor_AggregationCursor-next">AggregationCursor.prototype.next()</a></li></ul></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#aggregationcursor_AggregationCursor">AggregationCursor()</a></li><li><a href="#aggregationcursor_AggregationCursor-addCursorFlag">AggregationCursor.prototype.addCursorFlag()</a></li><li><a href="#aggregationcursor_AggregationCursor-close">AggregationCursor.prototype.close()</a></li><li><a href="#aggregationcursor_AggregationCursor-eachAsync">AggregationCursor.prototype.eachAsync()</a></li><li><a href="#aggregationcursor_AggregationCursor-map">AggregationCursor.prototype.map()</a></li><li><a href="#aggregationcursor_AggregationCursor-next">AggregationCursor.prototype.next()</a></li></ul><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor"><a href="#aggregationcursor_AggregationCursor">AggregationCursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">agg
-<span class="method-type">&laquo;Aggregate&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>An AggregationCursor is a concurrency primitive for processing aggregation results one document at a time. It is analogous to QueryCursor.</p>
-
-<p>An AggregationCursor fulfills the Node.js streams3 API, in addition to several other mechanisms for loading documents from MongoDB one at a time.</p>
-
-<p>Creating an AggregationCursor executes the model's pre aggregate hooks, but <strong>not</strong> the model's post aggregate hooks.</p>
-
-<p>Unless you're an advanced user, do <strong>not</strong> instantiate this class directly. Use <a href="/docs/api.html#aggregate_Aggregate-cursor"><code>Aggregate#cursor()</code></a> instead.</p>  </div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-addCursorFlag"><a href="#aggregationcursor_AggregationCursor-addCursorFlag">AggregationCursor.prototype.addCursorFlag()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">flag
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;AggregationCursor&raquo;</span> this</li></ul><div><p>Adds a <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag">cursor flag</a>. Useful for setting the <code>noCursorTimeout</code> and <code>tailable</code> flags.</p>  </div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-close"><a href="#aggregationcursor_AggregationCursor-close">AggregationCursor.prototype.close()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Marks this cursor as closed. Will stop streaming and subsequent calls to <code>next()</code> will error.</p>  </div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-eachAsync"><a href="#aggregationcursor_AggregationCursor-eachAsync">AggregationCursor.prototype.eachAsync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.parallel]
-<span class="method-type">&laquo;Number&raquo;</span> the number of promises to execute in parallel. Defaults to 1.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> executed when all docs have been processed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute <code>fn</code> for every document in the cursor. If <code>fn</code> returns a promise, will wait for the promise to resolve before iterating on to the next one. Returns a promise that resolves when done.</p>  </div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-map"><a href="#aggregationcursor_AggregationCursor-map">AggregationCursor.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;AggregationCursor&raquo;</span> </li></ul><div><p>Registers a transform function which subsequently maps documents retrieved via the streams interface or <code>.next()</code></p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Map documents returned by `data` events</span>
-Thing.
-  find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-   doc.foo = <span class="hljs-string">"bar"</span>;
-   <span class="hljs-keyword">return</span> doc;
-  })
-  on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{ <span class="hljs-built_in">console</span>.log(doc.foo); });
-
-<span class="hljs-comment">// Or map documents returned by `.next()`</span>
-<span class="hljs-keyword">var</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-    doc.foo = <span class="hljs-string">"bar"</span>;
-    <span class="hljs-keyword">return</span> doc;
-  });
-cursor.next(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.foo);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="aggregationcursor_AggregationCursor-next"><a href="#aggregationcursor_AggregationCursor-next">AggregationCursor.prototype.next()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Get the next document from this cursor. Will return <code>null</code> when there are no documents left.</p>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/array.html b/docs/api/array.html
deleted file mode 100644
index fef92ccc8f8..00000000000
--- a/docs/api/array.html
+++ /dev/null
@@ -1,65 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Array</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title" style="font-weight: bold"><a href="array.html">Array</a></div><ul class="nav-item-sub"></ul></div></div></div><div class="api-content"><ul></ul></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/connection.html b/docs/api/connection.html
deleted file mode 100644
index 1dfad522b6f..00000000000
--- a/docs/api/connection.html
+++ /dev/null
@@ -1,219 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Connection</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title" style="font-weight: bold"><a href="connection.html">Connection</a></div><ul class="nav-item-sub"><li><a href="#connection_Connection">Connection()</a></li><li><a href="#connection_Connection-close">Connection.prototype.close()</a></li><li><a href="#connection_Connection-collection">Connection.prototype.collection()</a></li><li><a href="#connection_Connection-collections">Connection.prototype.collections</a></li><li><a href="#connection_Connection-config">Connection.prototype.config</a></li><li><a href="#connection_Connection-createCollection">Connection.prototype.createCollection()</a></li><li><a href="#connection_Connection-db">Connection.prototype.db</a></li><li><a href="#connection_Connection-deleteModel">Connection.prototype.deleteModel()</a></li><li><a href="#connection_Connection-dropCollection">Connection.prototype.dropCollection()</a></li><li><a href="#connection_Connection-dropDatabase">Connection.prototype.dropDatabase()</a></li><li><a href="#connection_Connection-get">Connection.prototype.get()</a></li><li><a href="#connection_Connection-host">Connection.prototype.host</a></li><li><a href="#connection_Connection-model">Connection.prototype.model()</a></li><li><a href="#connection_Connection-modelNames">Connection.prototype.modelNames()</a></li><li><a href="#connection_Connection-name">Connection.prototype.name</a></li><li><a href="#connection_Connection-openUri">Connection.prototype.openUri()</a></li><li><a href="#connection_Connection-pass">Connection.prototype.pass</a></li><li><a href="#connection_Connection-plugin">Connection.prototype.plugin()</a></li><li><a href="#connection_Connection-plugins">Connection.prototype.plugins</a></li><li><a href="#connection_Connection-port">Connection.prototype.port</a></li><li><a href="#connection_Connection-readyState">Connection.prototype.readyState</a></li><li><a href="#connection_Connection-set">Connection.prototype.set()</a></li><li><a href="#connection_Connection-startSession">Connection.prototype.startSession()</a></li><li><a href="#connection_Connection-useDb">Connection.prototype.useDb()</a></li><li><a href="#connection_Connection-user">Connection.prototype.user</a></li></ul></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#connection_Connection">Connection()</a></li><li><a href="#connection_Connection-close">Connection.prototype.close()</a></li><li><a href="#connection_Connection-collection">Connection.prototype.collection()</a></li><li><a href="#connection_Connection-collections">Connection.prototype.collections</a></li><li><a href="#connection_Connection-config">Connection.prototype.config</a></li><li><a href="#connection_Connection-createCollection">Connection.prototype.createCollection()</a></li><li><a href="#connection_Connection-db">Connection.prototype.db</a></li><li><a href="#connection_Connection-deleteModel">Connection.prototype.deleteModel()</a></li><li><a href="#connection_Connection-dropCollection">Connection.prototype.dropCollection()</a></li><li><a href="#connection_Connection-dropDatabase">Connection.prototype.dropDatabase()</a></li><li><a href="#connection_Connection-get">Connection.prototype.get()</a></li><li><a href="#connection_Connection-host">Connection.prototype.host</a></li><li><a href="#connection_Connection-model">Connection.prototype.model()</a></li><li><a href="#connection_Connection-modelNames">Connection.prototype.modelNames()</a></li><li><a href="#connection_Connection-name">Connection.prototype.name</a></li><li><a href="#connection_Connection-openUri">Connection.prototype.openUri()</a></li><li><a href="#connection_Connection-pass">Connection.prototype.pass</a></li><li><a href="#connection_Connection-plugin">Connection.prototype.plugin()</a></li><li><a href="#connection_Connection-plugins">Connection.prototype.plugins</a></li><li><a href="#connection_Connection-port">Connection.prototype.port</a></li><li><a href="#connection_Connection-readyState">Connection.prototype.readyState</a></li><li><a href="#connection_Connection-set">Connection.prototype.set()</a></li><li><a href="#connection_Connection-startSession">Connection.prototype.startSession()</a></li><li><a href="#connection_Connection-useDb">Connection.prototype.useDb()</a></li><li><a href="#connection_Connection-user">Connection.prototype.user</a></li></ul><hr class="separate-api-elements"><h3 id="connection_Connection"><a href="#connection_Connection">Connection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">base
-<span class="method-type">&laquo;Mongoose&raquo;</span> a mongoose instance</li></ul><div><p>Connection constructor</p>
-
-<p>For practical reasons, a Connection equals a Db.</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-close"><a href="#connection_Connection-close">Connection.prototype.close()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[force]
-<span class="method-type">&laquo;Boolean&raquo;</span> optional</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> self</li></ul><div><p>Closes the connection</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-collection"><a href="#connection_Connection-collection">Connection.prototype.collection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> of the collection</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional collection options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Collection&raquo;</span> collection instance</li></ul><div><p>Retrieves a collection, creating it if not cached.</p>
-
-<p>Not typically needed by applications. Just talk to your collection through your model.</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-collections"><a href="#connection_Connection-collections">Connection.prototype.collections</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>A hash of the collections associated with this connection</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-config"><a href="#connection_Connection-config">Connection.prototype.config</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>A hash of the global options that are associated with this connection</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-createCollection"><a href="#connection_Connection-createCollection">Connection.prototype.createCollection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">collection
-<span class="method-type">&laquo;string&raquo;</span> The collection to create</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Db.html#createCollection">MongoDB driver docs</a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Helper for <code>createCollection()</code>. Will explicitly create the given collection with specified options. Used to create <a href="https://docs.mongodb.com/manual/core/capped-collections/">capped collections</a> and <a href="https://docs.mongodb.com/manual/core/views/">views</a> from mongoose.</p>
-
-<p>Options are passed down without modification to the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Db.html#createCollection">MongoDB driver's <code>createCollection()</code> function</a></p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-db"><a href="#connection_Connection-db">Connection.prototype.db</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The mongodb.Db instance, set when the connection is opened</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-deleteModel"><a href="#connection_Connection-deleteModel">Connection.prototype.deleteModel()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|RegExp&raquo;</span> if string, the name of the model to remove. If regexp, removes all models whose name matches the regexp.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> this</li></ul><div><p>Removes the model named <code>name</code> from this connection, if it exists. You can use this function to clean up any models you created in your tests to prevent OverwriteModelErrors.</p>
-
-<h4>Example:</h4>
-
-<pre><code>conn.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-built_in">console</span>.log(conn.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// Model object</span>
-conn.deleteModel(<span class="hljs-string">'User'</span>);
-<span class="hljs-built_in">console</span>.log(conn.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// undefined</span>
-
-<span class="hljs-comment">// Usually useful in a Mocha `afterEach()` hook</span>
-afterEach(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  conn.deleteModel(<span class="hljs-regexp">/.+/</span>); <span class="hljs-comment">// Delete every model</span>
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-dropCollection"><a href="#connection_Connection-dropCollection">Connection.prototype.dropCollection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">collection
-<span class="method-type">&laquo;string&raquo;</span> The collection to delete</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Helper for <code>dropCollection()</code>. Will delete the given collection, including all documents and indexes.</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-dropDatabase"><a href="#connection_Connection-dropDatabase">Connection.prototype.dropDatabase()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Helper for <code>dropDatabase()</code>. Deletes the given database, including all collections, documents, and indexes.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> conn = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>);
-<span class="hljs-comment">// Deletes the entire 'mydb' database</span>
-<span class="hljs-keyword">await</span> conn.dropDatabase();</code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-get"><a href="#connection_Connection-get">Connection.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Gets the value of the option <code>key</code>. Equivalent to <code>conn.options[key]</code></p>
-
-<h4>Example:</h4>
-
-<pre><code>conn.get(<span class="hljs-string">'test'</span>); <span class="hljs-comment">// returns the 'test' value</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-host"><a href="#connection_Connection-host">Connection.prototype.host</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The host name portion of the URI. If multiple hosts, such as a replica set, this will contain the first host name in the URI</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>).host; <span class="hljs-comment">// "localhost"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-model"><a href="#connection_Connection-model">Connection.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|Function&raquo;</span> the model name or class extending Model</li><li class="param">[schema]
-<span class="method-type">&laquo;Schema&raquo;</span> a schema. necessary when defining a model</li><li class="param">[collection]
-<span class="method-type">&laquo;String&raquo;</span> name of mongodb collection (optional) if not given it will be induced from model name</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Model&raquo;</span> The compiled model</li></ul><div><p>Defines or retrieves a model.</p>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> db = mongoose.createConnection(..);
-db.model(<span class="hljs-string">'Venue'</span>, <span class="hljs-keyword">new</span> Schema(..));
-<span class="hljs-keyword">var</span> Ticket = db.model(<span class="hljs-string">'Ticket'</span>, <span class="hljs-keyword">new</span> Schema(..));
-<span class="hljs-keyword">var</span> Venue = db.model(<span class="hljs-string">'Venue'</span>);</code></pre>
-
-<p><em>When no <code>collection</code> argument is passed, Mongoose produces a collection name by passing the model <code>name</code> to the <a href="#utils_exports.toCollectionName">utils.toCollectionName</a> method. This method pluralizes the name. If you don't like this behavior, either pass a collection name or set your schemas collection name option.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { collection: <span class="hljs-string">'actor'</span> });
-
-<span class="hljs-comment">// or</span>
-
-schema.set(<span class="hljs-string">'collection'</span>, <span class="hljs-string">'actor'</span>);
-
-<span class="hljs-comment">// or</span>
-
-<span class="hljs-keyword">var</span> collectionName = <span class="hljs-string">'actor'</span>
-<span class="hljs-keyword">var</span> M = conn.model(<span class="hljs-string">'Actor'</span>, schema, collectionName)</code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-modelNames"><a href="#connection_Connection-modelNames">Connection.prototype.modelNames()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns an array of model names created on this connection.</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-name"><a href="#connection_Connection-name">Connection.prototype.name</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The name of the database this connection points to.</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>).name; <span class="hljs-comment">// "mydb"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-openUri"><a href="#connection_Connection-openUri">Connection.prototype.openUri()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">uri
-<span class="method-type">&laquo;String&raquo;</span> The URI to connect with.</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Passed on to http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Opens the connection with a URI using <code>MongoClient.connect()</code>.</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-pass"><a href="#connection_Connection-pass">Connection.prototype.pass</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The password specified in the URI</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://val:psw@localhost:27017/mydb'</span>).pass; <span class="hljs-comment">// "psw"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-plugin"><a href="#connection_Connection-plugin">Connection.prototype.plugin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> plugin callback</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> optional options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> this</li></ul><div><p>Declares a plugin executed on all schemas you pass to <code>conn.model()</code></p>
-
-<p>Equivalent to calling <code>.plugin(fn)</code> on each schema you create.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> db = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>);
-db.plugin(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Applied'</span>));
-db.plugins.length; <span class="hljs-comment">// 1</span>
-
-db.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({})); <span class="hljs-comment">// Prints "Applied"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-plugins"><a href="#connection_Connection-plugins">Connection.prototype.plugins</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The plugins that will be applied to all models created on this connection.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> db = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>);
-db.plugin(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Applied'</span>));
-db.plugins.length; <span class="hljs-comment">// 1</span>
-
-db.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({})); <span class="hljs-comment">// Prints "Applied"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-port"><a href="#connection_Connection-port">Connection.prototype.port</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The port portion of the URI. If multiple hosts, such as a replica set, this will contain the port from the first host name in the URI.</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/mydb'</span>).port; <span class="hljs-comment">// 27017</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-readyState"><a href="#connection_Connection-readyState">Connection.prototype.readyState</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Connection ready state</p>
-
-<ul>
-<li>0 = disconnected</li>
-<li>1 = connected</li>
-<li>2 = connecting</li>
-<li>3 = disconnecting</li>
-</ul>
-
-<p>Each state change emits its associated event name.</p>
-
-<h4>Example</h4>
-
-<pre><code>conn.on(<span class="hljs-string">'connected'</span>, callback);
-conn.on(<span class="hljs-string">'disconnected'</span>, callback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-set"><a href="#connection_Connection-set">Connection.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Any&raquo;</span> </li></ul><div><p>Sets the value of the option <code>key</code>. Equivalent to <code>conn.options[key] = val</code></p>
-
-<h2>Supported options include</h2>
-
-<ul>
-<li><code>maxTimeMS</code>: Set <a href="/docs/api.html#query_Query-maxTimeMS"><code>maxTimeMS</code></a> for all queries on this connection.</li>
-<li><code>useFindAndModify</code>: Set to <code>false</code> to work around the <a href="/docs/deprecations.html#-findandmodify-"><code>findAndModify()</code> deprecation warning</a></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code>conn.set(<span class="hljs-string">'test'</span>, <span class="hljs-string">'foo'</span>);
-conn.get(<span class="hljs-string">'test'</span>); <span class="hljs-comment">// 'foo'</span>
-conn.options.test; <span class="hljs-comment">// 'foo'</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-startSession"><a href="#connection_Connection-startSession">Connection.prototype.startSession()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#startSession">mongodb driver options</a></li><ul style="margin-top: 0.5em"><li>[options.causalConsistency=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to disable causal consistency</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&lt;ClientSession&gt;&raquo;</span> promise that resolves to a MongoDB driver <code>ClientSession</code></li></ul><div><p><em>Requires MongoDB >= 3.6.0.</em> Starts a <a href="https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions">MongoDB session</a> for benefits like causal consistency, <a href="https://docs.mongodb.com/manual/core/retryable-writes/">retryable writes</a>, and <a href="http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html">transactions</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = <span class="hljs-keyword">await</span> conn.startSession();
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session });
-<span class="hljs-keyword">await</span> doc.remove();
-<span class="hljs-comment">// `doc` will always be null, even if reading from a replica set</span>
-<span class="hljs-comment">// secondary. Without causal consistency, it is possible to</span>
-<span class="hljs-comment">// get a doc back from the below query if the query reads from a</span>
-<span class="hljs-comment">// secondary that is experiencing replication lag.</span>
-doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session, readPreference: <span class="hljs-string">'secondary'</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-useDb"><a href="#connection_Connection-useDb">Connection.prototype.useDb()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> The database name</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> New Connection Object</li></ul><div><p>Switches to a different database using the same connection pool.</p>
-
-<p>Returns a new connection object, with the new db.</p>  </div><hr class="separate-api-elements"><h3 id="connection_Connection-user"><a href="#connection_Connection-user">Connection.prototype.user</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The username specified in the URI</p>
-
-<h4>Example</h4>
-
-<pre><code>mongoose.createConnection(<span class="hljs-string">'mongodb://val:psw@localhost:27017/mydb'</span>).user; <span class="hljs-comment">// "val"</span></code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/document.html b/docs/api/document.html
deleted file mode 100644
index 41f45bd8b4e..00000000000
--- a/docs/api/document.html
+++ /dev/null
@@ -1,558 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Document</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title" style="font-weight: bold"><a href="document.html">Document</a></div><ul class="nav-item-sub"><li><a href="#document_Document-$ignore">Document.prototype.$ignore()</a></li><li><a href="#document_Document-$isDefault">Document.prototype.$isDefault()</a></li><li><a href="#document_Document-$isDeleted">Document.prototype.$isDeleted()</a></li><li><a href="#document_Document-$isEmpty">Document.prototype.$isEmpty()</a></li><li><a href="#document_Document-$locals">Document.prototype.$locals</a></li><li><a href="#document_Document-$markValid">Document.prototype.$markValid()</a></li><li><a href="#document_Document-$session">Document.prototype.$session()</a></li><li><a href="#document_Document-$set">Document.prototype.$set()</a></li><li><a href="#document_Document-depopulate">Document.prototype.depopulate()</a></li><li><a href="#document_Document-directModifiedPaths">Document.prototype.directModifiedPaths()</a></li><li><a href="#document_Document-equals">Document.prototype.equals()</a></li><li><a href="#document_Document-errors">Document.prototype.errors</a></li><li><a href="#document_Document-execPopulate">Document.prototype.execPopulate()</a></li><li><a href="#document_Document-get">Document.prototype.get()</a></li><li><a href="#document_Document-id">Document.prototype.id</a></li><li><a href="#document_Document-init">Document.prototype.init()</a></li><li><a href="#document_Document-inspect">Document.prototype.inspect()</a></li><li><a href="#document_Document-invalidate">Document.prototype.invalidate()</a></li><li><a href="#document_Document-isDirectModified">Document.prototype.isDirectModified()</a></li><li><a href="#document_Document-isDirectSelected">Document.prototype.isDirectSelected()</a></li><li><a href="#document_Document-isInit">Document.prototype.isInit()</a></li><li><a href="#document_Document-isModified">Document.prototype.isModified()</a></li><li><a href="#document_Document-isNew">Document.prototype.isNew</a></li><li><a href="#document_Document-isSelected">Document.prototype.isSelected()</a></li><li><a href="#document_Document-markModified">Document.prototype.markModified()</a></li><li><a href="#document_Document-modifiedPaths">Document.prototype.modifiedPaths()</a></li><li><a href="#document_Document-overwrite">Document.prototype.overwrite()</a></li><li><a href="#document_Document-populate">Document.prototype.populate()</a></li><li><a href="#document_Document-populated">Document.prototype.populated()</a></li><li><a href="#document_Document-replaceOne">Document.prototype.replaceOne()</a></li><li><a href="#document_Document-save">Document.prototype.save()</a></li><li><a href="#document_Document-schema">Document.prototype.schema</a></li><li><a href="#document_Document-set">Document.prototype.set()</a></li><li><a href="#document_Document-toJSON">Document.prototype.toJSON()</a></li><li><a href="#document_Document-toObject">Document.prototype.toObject()</a></li><li><a href="#document_Document-toString">Document.prototype.toString()</a></li><li><a href="#document_Document-unmarkModified">Document.prototype.unmarkModified()</a></li><li><a href="#document_Document-update">Document.prototype.update()</a></li><li><a href="#document_Document-updateOne">Document.prototype.updateOne()</a></li><li><a href="#document_Document-validate">Document.prototype.validate()</a></li><li><a href="#document_Document-validateSync">Document.prototype.validateSync()</a></li></ul></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#document_Document-$ignore">Document.prototype.$ignore()</a></li><li><a href="#document_Document-$isDefault">Document.prototype.$isDefault()</a></li><li><a href="#document_Document-$isDeleted">Document.prototype.$isDeleted()</a></li><li><a href="#document_Document-$isEmpty">Document.prototype.$isEmpty()</a></li><li><a href="#document_Document-$locals">Document.prototype.$locals</a></li><li><a href="#document_Document-$markValid">Document.prototype.$markValid()</a></li><li><a href="#document_Document-$session">Document.prototype.$session()</a></li><li><a href="#document_Document-$set">Document.prototype.$set()</a></li><li><a href="#document_Document-depopulate">Document.prototype.depopulate()</a></li><li><a href="#document_Document-directModifiedPaths">Document.prototype.directModifiedPaths()</a></li><li><a href="#document_Document-equals">Document.prototype.equals()</a></li><li><a href="#document_Document-errors">Document.prototype.errors</a></li><li><a href="#document_Document-execPopulate">Document.prototype.execPopulate()</a></li><li><a href="#document_Document-get">Document.prototype.get()</a></li><li><a href="#document_Document-id">Document.prototype.id</a></li><li><a href="#document_Document-init">Document.prototype.init()</a></li><li><a href="#document_Document-inspect">Document.prototype.inspect()</a></li><li><a href="#document_Document-invalidate">Document.prototype.invalidate()</a></li><li><a href="#document_Document-isDirectModified">Document.prototype.isDirectModified()</a></li><li><a href="#document_Document-isDirectSelected">Document.prototype.isDirectSelected()</a></li><li><a href="#document_Document-isInit">Document.prototype.isInit()</a></li><li><a href="#document_Document-isModified">Document.prototype.isModified()</a></li><li><a href="#document_Document-isNew">Document.prototype.isNew</a></li><li><a href="#document_Document-isSelected">Document.prototype.isSelected()</a></li><li><a href="#document_Document-markModified">Document.prototype.markModified()</a></li><li><a href="#document_Document-modifiedPaths">Document.prototype.modifiedPaths()</a></li><li><a href="#document_Document-overwrite">Document.prototype.overwrite()</a></li><li><a href="#document_Document-populate">Document.prototype.populate()</a></li><li><a href="#document_Document-populated">Document.prototype.populated()</a></li><li><a href="#document_Document-replaceOne">Document.prototype.replaceOne()</a></li><li><a href="#document_Document-save">Document.prototype.save()</a></li><li><a href="#document_Document-schema">Document.prototype.schema</a></li><li><a href="#document_Document-set">Document.prototype.set()</a></li><li><a href="#document_Document-toJSON">Document.prototype.toJSON()</a></li><li><a href="#document_Document-toObject">Document.prototype.toObject()</a></li><li><a href="#document_Document-toString">Document.prototype.toString()</a></li><li><a href="#document_Document-unmarkModified">Document.prototype.unmarkModified()</a></li><li><a href="#document_Document-update">Document.prototype.update()</a></li><li><a href="#document_Document-updateOne">Document.prototype.updateOne()</a></li><li><a href="#document_Document-validate">Document.prototype.validate()</a></li><li><a href="#document_Document-validateSync">Document.prototype.validateSync()</a></li></ul><hr class="separate-api-elements"><h3 id="document_Document-$ignore"><a href="#document_Document-$ignore">Document.prototype.$ignore()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the path to ignore</li></ul><div><p>Don't run validation on this path or persist changes to this path.</p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.foo = <span class="hljs-literal">null</span>;
-doc.$ignore(<span class="hljs-string">'foo'</span>);
-doc.save(); <span class="hljs-comment">// changes to foo will not be persisted and validators won't be run</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-$isDefault"><a href="#document_Document-$isDefault">Document.prototype.$isDefault()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if a path is set to its default.</p>
-
-<h4>Example</h4>
-
-<pre><code>MyModel = mongoose.model(<span class="hljs-string">'test'</span>, { name: { type: <span class="hljs-built_in">String</span>, <span class="hljs-keyword">default</span>: <span class="hljs-string">'Val '</span>} });
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> MyModel();
-m.$isDefault(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-$isDeleted"><a href="#document_Document-$isDeleted">Document.prototype.$isDeleted()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[val]
-<span class="method-type">&laquo;Boolean&raquo;</span> optional, overrides whether mongoose thinks the doc is deleted</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> whether mongoose thinks this doc is deleted.</li></ul><div><p>Getter/setter, determines whether the document was removed or not.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.remove(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-  product.$isDeleted(); <span class="hljs-comment">// true</span>
-  product.remove(); <span class="hljs-comment">// no-op, doesn't send anything to the db</span>
-
-  product.$isDeleted(<span class="hljs-literal">false</span>);
-  product.$isDeleted(); <span class="hljs-comment">// false</span>
-  product.remove(); <span class="hljs-comment">// will execute a remove against the db</span>
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-$isEmpty"><a href="#document_Document-$isEmpty">Document.prototype.$isEmpty()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if the given path is nullish or only contains empty objects. Useful for determining whether this subdoc will get stripped out by the <a href="/docs/guide.html#minimize">minimize option</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ nested: { foo: <span class="hljs-built_in">String</span> } });
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({});
-doc.$isEmpty(<span class="hljs-string">'nested'</span>); <span class="hljs-comment">// true</span>
-doc.nested.$isEmpty(); <span class="hljs-comment">// true</span>
-
-doc.nested.foo = <span class="hljs-string">'bar'</span>;
-doc.$isEmpty(<span class="hljs-string">'nested'</span>); <span class="hljs-comment">// false</span>
-doc.nested.$isEmpty(); <span class="hljs-comment">// false</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-$locals"><a href="#document_Document-$locals">Document.prototype.$locals</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Empty object that you can use for storing properties on the document. This is handy for passing data to middleware without conflicting with Mongoose internals.</p>
-
-<h4>Example:</h4>
-
-<pre><code>schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Mongoose will set `isNew` to `false` if `save()` succeeds</span>
-  <span class="hljs-keyword">this</span>.$locals.wasNew = <span class="hljs-keyword">this</span>.isNew;
-});
-
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Prints true if `isNew` was set before `save()`</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>.$locals.wasNew);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-$markValid"><a href="#document_Document-$markValid">Document.prototype.$markValid()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the field to mark as valid</li></ul><div><p>Marks a path as valid, removing existing validation errors.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-$session"><a href="#document_Document-$session">Document.prototype.$session()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[session]
-<span class="method-type">&laquo;ClientSession&raquo;</span> overwrite the current session</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ClientSession&raquo;</span> </li></ul><div><p>Getter/setter around the session associated with this document. Used to automatically set <code>session</code> if you <code>save()</code> a doc that you got from a query with an associated session.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = MyModel.startSession();
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> MyModel.findOne().session(session);
-doc.$session() === session; <span class="hljs-comment">// true</span>
-doc.$session(<span class="hljs-literal">null</span>);
-doc.$session() === <span class="hljs-literal">null</span>; <span class="hljs-comment">// true</span></code></pre>
-
-<p>If this is a top-level document, setting the session propagates to all child docs.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-$set"><a href="#document_Document-$set">Document.prototype.$set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object&raquo;</span> path or object of key/vals to set</li><li class="param">val
-<span class="method-type">&laquo;Any&raquo;</span> the value to set</li><li class="param">[type]
-<span class="method-type">&laquo;Schema|String|Number|Buffer|*&raquo;</span> optionally specify a type for &quot;on-the-fly&quot; attributes</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optionally specify options that modify the behavior of the set</li></ul><div><p>Alias for <code>set()</code>, used internally to avoid conflicts</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-depopulate"><a href="#document_Document-depopulate">Document.prototype.depopulate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Document&raquo;</span> this</li></ul><div><p>Takes a populated field and returns it to its unpopulated state.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findOne().populate(<span class="hljs-string">'author'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.author.name); <span class="hljs-comment">// Dr.Seuss</span>
-  <span class="hljs-built_in">console</span>.log(doc.depopulate(<span class="hljs-string">'author'</span>));
-  <span class="hljs-built_in">console</span>.log(doc.author); <span class="hljs-comment">// '5144cf8050f071d979c118a7'</span>
-})</code></pre>
-
-<p>If the path was not populated, this is a no-op.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-directModifiedPaths"><a href="#document_Document-directModifiedPaths">Document.prototype.directModifiedPaths()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns the list of paths that have been directly modified. A direct modified path is a path that you explicitly set, whether via <code>doc.foo = 'bar'</code>, <code>Object.assign(doc, { foo: 'bar' })</code>, or <code>doc.set('foo', 'bar')</code>.</p>
-
-<p>A path <code>a</code> may be in <code>modifiedPaths()</code> but not in <code>directModifiedPaths()</code> because a child of <code>a</code> was directly modified.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ foo: <span class="hljs-built_in">String</span>, nested: { bar: <span class="hljs-built_in">String</span> } });
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">await</span> Model.create({ foo: <span class="hljs-string">'original'</span>, nested: { bar: <span class="hljs-string">'original'</span> } });
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Model.findOne();
-doc.nested.bar = <span class="hljs-string">'modified'</span>;
-doc.directModifiedPaths(); <span class="hljs-comment">// ['nested.bar']</span>
-doc.modifiedPaths(); <span class="hljs-comment">// ['nested', 'nested.bar']</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-equals"><a href="#document_Document-equals">Document.prototype.equals()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Document&raquo;</span> a document to compare</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if the Document stores the same data as doc.</p>
-
-<p>Documents are considered equal when they have matching <code>_id</code>s, unless neither document has an <code>_id</code>, in which case this function falls back to using <code>deepEqual()</code>.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-errors"><a href="#document_Document-errors">Document.prototype.errors</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Hash containing current validation errors.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-execPopulate"><a href="#document_Document-execPopulate">Document.prototype.execPopulate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback. If specified, a promise will <strong>not</strong> be returned</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> promise that resolves to the document when population is done</li></ul><div><p>Explicitly executes population and returns a promise. Useful for ES2015 integration.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> promise = doc.
-  populate(<span class="hljs-string">'company'</span>).
-  populate({
-    path: <span class="hljs-string">'notes'</span>,
-    match: <span class="hljs-regexp">/airline/</span>,
-    select: <span class="hljs-string">'text'</span>,
-    model: <span class="hljs-string">'modelName'</span>
-    options: opts
-  }).
-  execPopulate();
-
-<span class="hljs-comment">// summary</span>
-doc.execPopulate().then(resolve, reject);</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-get"><a href="#document_Document-get">Document.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[type]
-<span class="method-type">&laquo;Schema|String|Number|Buffer|*&raquo;</span> optionally specify a type for on-the-fly attributes</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.virtuals=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> Apply virtuals before getting this path</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> If false, skip applying getters and just get the raw value</li></ul></ul><div><p>Returns the value of a path.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// path</span>
-doc.get(<span class="hljs-string">'age'</span>) <span class="hljs-comment">// 47</span>
-
-<span class="hljs-comment">// dynamic casting to a string</span>
-doc.get(<span class="hljs-string">'age'</span>, <span class="hljs-built_in">String</span>) <span class="hljs-comment">// "47"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-id"><a href="#document_Document-id">Document.prototype.id</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The string version of this documents _id.</p>
-
-<h4>Note:</h4>
-
-<p>This getter exists on all documents by default. The getter can be disabled by setting the <code>id</code> <a href="/docs/guide.html#id">option</a> of its <code>Schema</code> to false at construction time.</p>
-
-<pre><code><span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { id: <span class="hljs-literal">false</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-init"><a href="#document_Document-init">Document.prototype.init()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> document returned by mongo</li></ul><div><p>Initializes the document without setters or marking anything modified.</p>
-
-<p>Called internally after a document is returned from mongodb. Normally, you do <strong>not</strong> need to call this function on your own.</p>
-
-<p>This function triggers <code>init</code> <a href="/docs/middleware.html">middleware</a>. Note that <code>init</code> hooks are <a href="/docs/middleware.html#synchronous">synchronous</a>.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-inspect"><a href="#document_Document-inspect">Document.prototype.inspect()</a></h3><div><p>Helper for console.log</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-invalidate"><a href="#document_Document-invalidate">Document.prototype.invalidate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the field to invalidate</li><li class="param">errorMsg
-<span class="method-type">&laquo;String|Error&raquo;</span> the error which states the reason <code>path</code> was invalid</li><li class="param">value
-<span class="method-type">&laquo;Object|String|Number|any&raquo;</span> optional invalid value</li><li class="param">[kind]
-<span class="method-type">&laquo;String&raquo;</span> optional <code>kind</code> property for the error</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ValidationError&raquo;</span> the current ValidationError, with all currently invalidated paths</li></ul><div><p>Marks a path as invalid, causing validation to fail.</p>
-
-<p>The <code>errorMsg</code> argument will become the message of the <code>ValidationError</code>.</p>
-
-<p>The <code>value</code> argument (if passed) will be available through the <code>ValidationError.value</code> property.</p>
-
-<pre><code>doc.invalidate(<span class="hljs-string">'size'</span>, <span class="hljs-string">'must be less than 20'</span>, <span class="hljs-number">14</span>);
-
-doc.validate(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(err)
-  <span class="hljs-comment">// prints</span>
-  { message: <span class="hljs-string">'Validation failed'</span>,
-    name: <span class="hljs-string">'ValidationError'</span>,
-    errors:
-     { size:
-        { message: <span class="hljs-string">'must be less than 20'</span>,
-          name: <span class="hljs-string">'ValidatorError'</span>,
-          path: <span class="hljs-string">'size'</span>,
-          type: <span class="hljs-string">'user defined'</span>,
-          value: <span class="hljs-number">14</span> } } }
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-isDirectModified"><a href="#document_Document-isDirectModified">Document.prototype.isDirectModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if <code>path</code> was directly set and modified, else false.</p>
-
-<h4>Example</h4>
-
-<pre><code>doc.set(<span class="hljs-string">'documents.0.title'</span>, <span class="hljs-string">'changed'</span>);
-doc.isDirectModified(<span class="hljs-string">'documents.0.title'</span>) <span class="hljs-comment">// true</span>
-doc.isDirectModified(<span class="hljs-string">'documents'</span>) <span class="hljs-comment">// false</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-isDirectSelected"><a href="#document_Document-isDirectSelected">Document.prototype.isDirectSelected()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if <code>path</code> was explicitly selected. If no projection, always returns true.</p>
-
-<h4>Example</h4>
-
-<pre><code>Thing.findOne().select(<span class="hljs-string">'nested.name'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-   doc.isDirectSelected(<span class="hljs-string">'nested.name'</span>) <span class="hljs-comment">// true</span>
-   doc.isDirectSelected(<span class="hljs-string">'nested.otherName'</span>) <span class="hljs-comment">// false</span>
-   doc.isDirectSelected(<span class="hljs-string">'nested'</span>)  <span class="hljs-comment">// false</span>
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-isInit"><a href="#document_Document-isInit">Document.prototype.isInit()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if <code>path</code> was initialized.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-isModified"><a href="#document_Document-isModified">Document.prototype.isModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> optional</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Returns true if this document was modified, else false.</p>
-
-<p>If <code>path</code> is given, checks if a path or any full path containing <code>path</code> as part of its path chain has been modified.</p>
-
-<h4>Example</h4>
-
-<pre><code>doc.set(<span class="hljs-string">'documents.0.title'</span>, <span class="hljs-string">'changed'</span>);
-doc.isModified()                      <span class="hljs-comment">// true</span>
-doc.isModified(<span class="hljs-string">'documents'</span>)           <span class="hljs-comment">// true</span>
-doc.isModified(<span class="hljs-string">'documents.0.title'</span>)   <span class="hljs-comment">// true</span>
-doc.isModified(<span class="hljs-string">'documents otherProp'</span>) <span class="hljs-comment">// true</span>
-doc.isDirectModified(<span class="hljs-string">'documents'</span>)     <span class="hljs-comment">// false</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-isNew"><a href="#document_Document-isNew">Document.prototype.isNew</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Boolean flag specifying if the document is new.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-isSelected"><a href="#document_Document-isSelected">Document.prototype.isSelected()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Checks if <code>path</code> was selected in the source query which initialized this document.</p>
-
-<h4>Example</h4>
-
-<pre><code>Thing.findOne().select(<span class="hljs-string">'name'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-   doc.isSelected(<span class="hljs-string">'name'</span>) <span class="hljs-comment">// true</span>
-   doc.isSelected(<span class="hljs-string">'age'</span>)  <span class="hljs-comment">// false</span>
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-markModified"><a href="#document_Document-markModified">Document.prototype.markModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the path to mark modified</li><li class="param">[scope]
-<span class="method-type">&laquo;Document&raquo;</span> the scope to run validators with</li></ul><div><p>Marks the path as having pending changes to write to the db.</p>
-
-<p><em>Very helpful when using <a href="./schematypes.html#mixed">Mixed</a> types.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.mixed.type = <span class="hljs-string">'changed'</span>;
-doc.markModified(<span class="hljs-string">'mixed.type'</span>);
-doc.save() <span class="hljs-comment">// changes to mixed.type are now persisted</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-modifiedPaths"><a href="#document_Document-modifiedPaths">Document.prototype.modifiedPaths()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.includeChildren=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns children of modified paths as well. For example, if false, the list of modified paths for <code>doc.colors = { primary: &#39;blue&#39; };</code> will <strong>not</strong> contain <code>colors.primary</code>. If true, <code>modifiedPaths()</code> will return an array that contains <code>colors.primary</code>.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns the list of paths that have been modified.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-overwrite"><a href="#document_Document-overwrite">Document.prototype.overwrite()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;Object&raquo;</span> the object to overwrite this document with</li></ul><div><p>Overwrite all values in this document with the values of <code>obj</code>, except for immutable properties. Behaves similarly to <code>set()</code>, except for it unsets all properties that aren't in <code>obj</code>.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-populate"><a href="#document_Document-populate">Document.prototype.populate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String|Object&raquo;</span> The path to populate or an options object</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> When passed, population is invoked</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Document&raquo;</span> this</li></ul><div><p>Populates document references, executing the <code>callback</code> when complete. If you want to use promises instead, use this function with <a href="#document_Document-execPopulate"><code>execPopulate()</code></a></p>
-
-<h4>Example:</h4>
-
-<pre><code>doc
-.populate(<span class="hljs-string">'company'</span>)
-.populate({
-  path: <span class="hljs-string">'notes'</span>,
-  match: <span class="hljs-regexp">/airline/</span>,
-  select: <span class="hljs-string">'text'</span>,
-  model: <span class="hljs-string">'modelName'</span>
-  options: opts
-}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-  assert(doc._id === user._id) <span class="hljs-comment">// the document itself is passed</span>
-})
-
-<span class="hljs-comment">// summary</span>
-doc.populate(path)                   <span class="hljs-comment">// not executed</span>
-doc.populate(options);               <span class="hljs-comment">// not executed</span>
-doc.populate(path, callback)         <span class="hljs-comment">// executed</span>
-doc.populate(options, callback);     <span class="hljs-comment">// executed</span>
-doc.populate(callback);              <span class="hljs-comment">// executed</span>
-doc.populate(options).execPopulate() <span class="hljs-comment">// executed, returns promise</span></code></pre>
-
-<h4>NOTE:</h4>
-
-<p>Population does not occur unless a <code>callback</code> is passed <em>or</em> you explicitly call <code>execPopulate()</code>. Passing the same path a second time will overwrite the previous path options. See <a href="#model_Model.populate">Model.populate()</a> for explaination of options.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-populated"><a href="#document_Document-populated">Document.prototype.populated()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array,ObjectId,Number,Buffer,String,undefined&raquo;</span> </li></ul><div><p>Gets _id(s) used during population of the given <code>path</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findOne().populate(<span class="hljs-string">'author'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.author.name)         <span class="hljs-comment">// Dr.Seuss</span>
-  <span class="hljs-built_in">console</span>.log(doc.populated(<span class="hljs-string">'author'</span>)) <span class="hljs-comment">// '5144cf8050f071d979c118a7'</span>
-})</code></pre>
-
-<p>If the path was not populated, undefined is returned.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-replaceOne"><a href="#document_Document-replaceOne">Document.prototype.replaceOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Sends a replaceOne command with this document <code>_id</code> as the query selector.</p>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li>same as in <a href="#model_Model.replaceOne">Model.replaceOne</a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="document_Document-save"><a href="#document_Document-save">Document.prototype.save()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> options optional options</li><ul style="margin-top: 0.5em"><li>[options.safe]
-<span class="method-type">&laquo;Object&raquo;</span> (DEPRECATED) overrides <a href="http://mongoosejs.com//docs/guide.html#safe">schema&#39;s safe option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.validateBeforeSave]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to save without validating.</li></ul><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns undefined if used with callback or a Promise otherwise.</li></ul><div><p>Saves this document.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.sold = <span class="hljs-built_in">Date</span>.now();
-product.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-})</code></pre>
-
-<p>The callback will receive two parameters</p>
-
-<ol>
-<li><code>err</code> if an error occurred</li>
-<li><code>product</code> which is the saved <code>product</code></li>
-</ol>
-
-<p>As an extra measure of flow control, save will return a Promise.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.save().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">product</span>) </span>{
-   ...
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-schema"><a href="#document_Document-schema">Document.prototype.schema</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The documents schema.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-set"><a href="#document_Document-set">Document.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object&raquo;</span> path or object of key/vals to set</li><li class="param">val
-<span class="method-type">&laquo;Any&raquo;</span> the value to set</li><li class="param">[type]
-<span class="method-type">&laquo;Schema|String|Number|Buffer|*&raquo;</span> optionally specify a type for &quot;on-the-fly&quot; attributes</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optionally specify options that modify the behavior of the set</li></ul><div><p>Sets the value of a path, or many paths.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// path, value</span>
-doc.set(path, value)
-
-<span class="hljs-comment">// object</span>
-doc.set({
-    path  : value
-  , path2 : {
-       path  : value
-    }
-})
-
-<span class="hljs-comment">// on-the-fly cast to number</span>
-doc.set(path, value, <span class="hljs-built_in">Number</span>)
-
-<span class="hljs-comment">// on-the-fly cast to string</span>
-doc.set(path, value, <span class="hljs-built_in">String</span>)
-
-<span class="hljs-comment">// changing strict mode behavior</span>
-doc.set(path, value, { strict: <span class="hljs-literal">false</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-toJSON"><a href="#document_Document-toJSON">Document.prototype.toJSON()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>The return value of this method is used in calls to JSON.stringify(doc).</p>
-
-<p>This method accepts the same options as <a href="#document_Document-toObject">Document#toObject</a>. To apply the options to every document of your schema by default, set your <a href="#schema_Schema">schemas</a> <code>toJSON</code> option to the same argument.</p>
-
-<pre><code>schema.set(<span class="hljs-string">'toJSON'</span>, { virtuals: <span class="hljs-literal">true</span> })</code></pre>
-
-<p>See <a href="/docs/guide.html#toJSON">schema options</a> for details.</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-toObject"><a href="#document_Document-toObject">Document.prototype.toObject()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, apply all getters, including virtuals</li></ul><ul style="margin-top: 0.5em"><li>[options.virtuals=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, apply virtuals. Use <code>{ getters: true, virtuals: false }</code> to just apply getters, not virtuals</li></ul><ul style="margin-top: 0.5em"><li>[options.minimize=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, omit any empty objects from the output</li></ul><ul style="margin-top: 0.5em"><li>[options.transform=null]
-<span class="method-type">&laquo;Function|null&raquo;</span> if set, mongoose will call this function to allow you to transform the returned object</li></ul><ul style="margin-top: 0.5em"><li>[options.depopulate=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, replace any conventionally populated paths with the original id in the output. Has no affect on virtual populated paths.</li></ul><ul style="margin-top: 0.5em"><li>[options.versionKey=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> if false, exclude the version key (<code>__v</code> by default) from the output</li></ul><ul style="margin-top: 0.5em"><li>[options.flattenMaps=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, convert Maps to POJOs. Useful if you want to <code>JSON.stringify()</code> the result of <code>toObject()</code>.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> js object</li></ul><div><p>Converts this document into a plain javascript object, ready for storage in MongoDB.</p>
-
-<p>Buffers are converted to instances of <a href="http://mongodb.github.com/node-mongodb-native/api-bson-generated/binary.html">mongodb.Binary</a> for proper storage.</p>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>getters</code> apply all getters (path and virtual getters), defaults to false</li>
-<li><code>virtuals</code> apply virtual getters (can override <code>getters</code> option), defaults to false</li>
-<li><code>minimize</code> remove empty objects (defaults to true)</li>
-<li><code>transform</code> a transform function to apply to the resulting document before returning</li>
-<li><code>depopulate</code> depopulate any populated paths, replacing them with their original refs (defaults to false)</li>
-<li><code>versionKey</code> whether to include the version key (defaults to true)</li>
-</ul>
-
-<h4>Getters/Virtuals</h4>
-
-<p>Example of only applying path getters</p>
-
-<pre><code>doc.toObject({ getters: <span class="hljs-literal">true</span>, virtuals: <span class="hljs-literal">false</span> })</code></pre>
-
-<p>Example of only applying virtual getters</p>
-
-<pre><code>doc.toObject({ virtuals: <span class="hljs-literal">true</span> })</code></pre>
-
-<p>Example of applying both path and virtual getters</p>
-
-<pre><code>doc.toObject({ getters: <span class="hljs-literal">true</span> })</code></pre>
-
-<p>To apply these options to every document of your schema by default, set your <a href="#schema_Schema">schemas</a> <code>toObject</code> option to the same argument.</p>
-
-<pre><code>schema.set(<span class="hljs-string">'toObject'</span>, { virtuals: <span class="hljs-literal">true</span> })</code></pre>
-
-<h4>Transform</h4>
-
-<p>We may need to perform a transformation of the resulting object based on some criteria, say to remove some sensitive information or return a custom object. In this case we set the optional <code>transform</code> function.</p>
-
-<p>Transform functions receive three arguments</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{}</code></pre>
-
-<ul>
-<li><code>doc</code> The mongoose document which is being converted</li>
-<li><code>ret</code> The plain object representation which has been converted</li>
-<li><code>options</code> The options in use (either schema options or the options passed inline)</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// specify the transform schema option</span>
-<span class="hljs-keyword">if</span> (!schema.options.toObject) schema.options.toObject = {};
-schema.options.toObject.transform = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-comment">// remove the _id of every document before returning the result</span>
-  <span class="hljs-keyword">delete</span> ret._id;
-  <span class="hljs-keyword">return</span> ret;
-}
-
-<span class="hljs-comment">// without the transformation in the schema</span>
-doc.toObject(); <span class="hljs-comment">// { _id: 'anId', name: 'Wreck-it Ralph' }</span>
-
-<span class="hljs-comment">// with the transformation</span>
-doc.toObject(); <span class="hljs-comment">// { name: 'Wreck-it Ralph' }</span></code></pre>
-
-<p>With transformations we can do a lot more than remove properties. We can even return completely new customized objects:</p>
-
-<pre><code><span class="hljs-keyword">if</span> (!schema.options.toObject) schema.options.toObject = {};
-schema.options.toObject.transform = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-keyword">return</span> { movie: ret.name }
-}
-
-<span class="hljs-comment">// without the transformation in the schema</span>
-doc.toObject(); <span class="hljs-comment">// { _id: 'anId', name: 'Wreck-it Ralph' }</span>
-
-<span class="hljs-comment">// with the transformation</span>
-doc.toObject(); <span class="hljs-comment">// { movie: 'Wreck-it Ralph' }</span></code></pre>
-
-<p><em>Note: if a transform function returns <code>undefined</code>, the return value will be ignored.</em></p>
-
-<p>Transformations may also be applied inline, overridding any transform set in the options:</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">xform</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-keyword">return</span> { inline: ret.name, custom: <span class="hljs-literal">true</span> }
-}
-
-<span class="hljs-comment">// pass the transform as an inline option</span>
-doc.toObject({ transform: xform }); <span class="hljs-comment">// { inline: 'Wreck-it Ralph', custom: true }</span></code></pre>
-
-<p>If you want to skip transformations, use <code>transform: false</code>:</p>
-
-<pre><code><span class="hljs-keyword">if</span> (!schema.options.toObject) schema.options.toObject = {};
-schema.options.toObject.hide = <span class="hljs-string">'_id'</span>;
-schema.options.toObject.transform = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, ret, options</span>) </span>{
-  <span class="hljs-keyword">if</span> (options.hide) {
-    options.hide.split(<span class="hljs-string">' '</span>).forEach(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">prop</span>) </span>{
-      <span class="hljs-keyword">delete</span> ret[prop];
-    });
-  }
-  <span class="hljs-keyword">return</span> ret;
-}
-
-<span class="hljs-keyword">var</span> doc = <span class="hljs-keyword">new</span> Doc({ _id: <span class="hljs-string">'anId'</span>, secret: <span class="hljs-number">47</span>, name: <span class="hljs-string">'Wreck-it Ralph'</span> });
-doc.toObject();                                        <span class="hljs-comment">// { secret: 47, name: 'Wreck-it Ralph' }</span>
-doc.toObject({ hide: <span class="hljs-string">'secret _id'</span>, transform: <span class="hljs-literal">false</span> });<span class="hljs-comment">// { _id: 'anId', secret: 47, name: 'Wreck-it Ralph' }</span>
-doc.toObject({ hide: <span class="hljs-string">'secret _id'</span>, transform: <span class="hljs-literal">true</span> }); <span class="hljs-comment">// { name: 'Wreck-it Ralph' }</span></code></pre>
-
-<p>Transforms are applied <em>only to the document and are not applied to sub-documents</em>.</p>
-
-<p>Transforms, like all of these options, are also available for <code>toJSON</code>.</p>
-
-<p>See <a href="/docs/guide.html#toObject">schema options</a> for some more details.</p>
-
-<p><em>During save, no custom options are applied to the document before being sent to the database.</em></p>  </div><hr class="separate-api-elements"><h3 id="document_Document-toString"><a href="#document_Document-toString">Document.prototype.toString()</a></h3><div><p>Helper for console.log</p>  </div><hr class="separate-api-elements"><h3 id="document_Document-unmarkModified"><a href="#document_Document-unmarkModified">Document.prototype.unmarkModified()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> the path to unmark modified</li></ul><div><p>Clears the modified state on the specified path.</p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.foo = <span class="hljs-string">'bar'</span>;
-doc.unmarkModified(<span class="hljs-string">'foo'</span>);
-doc.save(); <span class="hljs-comment">// changes to foo will not be persisted</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-update"><a href="#document_Document-update">Document.prototype.update()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Sends an update command with this document <code>_id</code> as the query selector.</p>
-
-<h4>Example:</h4>
-
-<pre><code>weirdCar.update({$inc: {wheels:<span class="hljs-number">1</span>}}, { w: <span class="hljs-number">1</span> }, callback);</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li>same as in <a href="#model_Model.update">Model.update</a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="document_Document-updateOne"><a href="#document_Document-updateOne">Document.prototype.updateOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Sends an updateOne command with this document <code>_id</code> as the query selector.</p>
-
-<h4>Example:</h4>
-
-<pre><code>weirdCar.updateOne({$inc: {wheels:<span class="hljs-number">1</span>}}, { w: <span class="hljs-number">1</span> }, callback);</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li>same as in <a href="#model_Model.updateOne">Model.updateOne</a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="document_Document-validate"><a href="#document_Document-validate">Document.prototype.validate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">optional
-<span class="method-type">&laquo;Object&raquo;</span> options internal options</li><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> optional callback called after validation completes, passing an error if one occurred</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> Promise</li></ul><div><p>Executes registered validation rules for this document.</p>
-
-<h4>Note:</h4>
-
-<p>This method is called <code>pre</code> save and if a validation rule is violated, <a href="#model_Model-save">save</a> is aborted and the error is returned to your <code>callback</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>doc.validate(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) handleError(err);
-  <span class="hljs-keyword">else</span> <span class="hljs-comment">// validation passed</span>
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="document_Document-validateSync"><a href="#document_Document-validateSync">Document.prototype.validateSync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">pathsToValidate
-<span class="method-type">&laquo;Array|string&raquo;</span> only validate the given paths</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ValidationError,undefined&raquo;</span> ValidationError if there are errors during validation, or undefined if there is no error.</li></ul><div><p>Executes registered validation rules (skipping asynchronous validators) for this document.</p>
-
-<h4>Note:</h4>
-
-<p>This method is useful if you need synchronous validation.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> err = doc.validateSync();
-<span class="hljs-keyword">if</span> ( err ){
-  handleError( err );
-} <span class="hljs-keyword">else</span> {
-  <span class="hljs-comment">// validation passed</span>
-}</code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/error.html b/docs/api/error.html
deleted file mode 100644
index 1a43df5f96d..00000000000
--- a/docs/api/error.html
+++ /dev/null
@@ -1,92 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Error</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title" style="font-weight: bold"><a href="error.html">Error</a></div><ul class="nav-item-sub"><li><a href="#mongooseerror_MongooseError">Error()</a></li><li><a href="#error_Error-CastError">Error.CastError</a></li><li><a href="#error_Error-DivergentArrayError">Error.DivergentArrayError</a></li><li><a href="#error_Error-DocumentNotFoundError">Error.DocumentNotFoundError</a></li><li><a href="#error_Error-MissingSchemaError">Error.MissingSchemaError</a></li><li><a href="#error_Error-OverwriteModelError">Error.OverwriteModelError</a></li><li><a href="#error_Error-ParallelSaveError">Error.ParallelSaveError</a></li><li><a href="#error_Error-ValidationError">Error.ValidationError</a></li><li><a href="#error_Error-ValidatorError">Error.ValidatorError</a></li><li><a href="#error_Error-VersionError">Error.VersionError</a></li><li><a href="#error_Error-messages">Error.messages</a></li><li><a href="#error_Error-name">Error.prototype.name</a></li></ul></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#mongooseerror_MongooseError">Error()</a></li><li><a href="#error_Error-CastError">Error.CastError</a></li><li><a href="#error_Error-DivergentArrayError">Error.DivergentArrayError</a></li><li><a href="#error_Error-DocumentNotFoundError">Error.DocumentNotFoundError</a></li><li><a href="#error_Error-MissingSchemaError">Error.MissingSchemaError</a></li><li><a href="#error_Error-OverwriteModelError">Error.OverwriteModelError</a></li><li><a href="#error_Error-ParallelSaveError">Error.ParallelSaveError</a></li><li><a href="#error_Error-ValidationError">Error.ValidationError</a></li><li><a href="#error_Error-ValidatorError">Error.ValidatorError</a></li><li><a href="#error_Error-VersionError">Error.VersionError</a></li><li><a href="#error_Error-messages">Error.messages</a></li><li><a href="#error_Error-name">Error.prototype.name</a></li></ul><hr class="separate-api-elements"><h3 id="mongooseerror_MongooseError"><a href="#mongooseerror_MongooseError">Error()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">msg
-<span class="method-type">&laquo;String&raquo;</span> Error message</li></ul><div><p>MongooseError constructor. MongooseError is the base class for all Mongoose-specific errors.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ answer: <span class="hljs-built_in">Number</span> }));
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({ answer: <span class="hljs-string">'not a number'</span> });
-<span class="hljs-keyword">const</span> err = doc.validateSync();
-
-err <span class="hljs-keyword">instanceof</span> mongoose.Error; <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="error_Error-CastError"><a href="#error_Error-CastError">Error.CastError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when mongoose failed to cast a value.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-DivergentArrayError"><a href="#error_Error-DivergentArrayError">Error.DivergentArrayError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error will be returned if you used an array projection and then modified the array in an unsafe way.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-DocumentNotFoundError"><a href="#error_Error-DocumentNotFoundError">Error.DocumentNotFoundError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when <code>save()</code> fails because the underlying document was not found. The constructor takes one parameter, the conditions that mongoose passed to <code>update()</code> when trying to update the document.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-MissingSchemaError"><a href="#error_Error-MissingSchemaError">Error.MissingSchemaError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Thrown when you try to access a model that has not been registered yet</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-OverwriteModelError"><a href="#error_Error-OverwriteModelError">Error.OverwriteModelError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Thrown when a model with the given name was already registered on the connection. See <a href="/docs/faq.html#overwrite-model-error">the FAQ about <code>OverwriteModelError</code></a>.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-ParallelSaveError"><a href="#error_Error-ParallelSaveError">Error.ParallelSaveError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when you call <code>save()</code> multiple times on the same document in parallel. See the <a href="/docs/faq.html">FAQ</a> for more information.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-ValidationError"><a href="#error_Error-ValidationError">Error.ValidationError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when <a href="/docs/validation.html">validation</a> failed. The <code>errors</code> property contains an object whose keys are the paths that failed and whose values are instances of CastError or ValidationError.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-ValidatorError"><a href="#error_Error-ValidatorError">Error.ValidatorError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>A <code>ValidationError</code> has a hash of <code>errors</code> that contain individual <code>ValidatorError</code> instances</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-VersionError"><a href="#error_Error-VersionError">Error.VersionError</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>An instance of this error class will be returned when you call <code>save()</code> after the document in the database was changed in a potentially unsafe way. See the <a href="/docs/guide.html#versionKey"><code>versionKey</code> option</a> for more information.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-messages"><a href="#error_Error-messages">Error.messages</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The default built-in validator error messages.</p>  </div><hr class="separate-api-elements"><h3 id="error_Error-name"><a href="#error_Error-name">Error.prototype.name</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;String&raquo;</span></li></ul><div><p>The name of the error. The name uniquely identifies this Mongoose error. The possible values are:</p>
-
-<ul>
-<li><code>MongooseError</code>: general Mongoose error</li>
-<li><code>CastError</code>: Mongoose could not convert a value to the type defined in the schema path. May be in a <code>ValidationError</code> class' <code>errors</code> property.</li>
-<li><code>DisconnectedError</code>: This <a href="connections.html">connection</a> timed out in trying to reconnect to MongoDB and will not successfully reconnect to MongoDB unless you explicitly reconnect.</li>
-<li><code>DivergentArrayError</code>: You attempted to <code>save()</code> an array that was modified after you loaded it with a <code>$elemMatch</code> or similar projection</li>
-<li><code>MissingSchemaError</code>: You tried to access a model with <a href="api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> that was not defined</li>
-<li><code>DocumentNotFoundError</code>: The document you tried to <a href="api.html#document_Document-save"><code>save()</code></a> was not found</li>
-<li><code>ValidatorError</code>: error from an individual schema path's validator</li>
-<li><code>ValidationError</code>: error returned from <a href="api.html#document_Document-validate"><code>validate()</code></a> or <a href="api.html#document_Document-validateSync"><code>validateSync()</code></a>. Contains zero or more <code>ValidatorError</code> instances in <code>.errors</code> property.</li>
-<li><code>MissingSchemaError</code>: You called <code>mongoose.Document()</code> without a schema</li>
-<li><code>ObjectExpectedError</code>: Thrown when you set a nested path to a non-object value with <a href="guide.html#strict">strict mode set</a>.</li>
-<li><code>ObjectParameterError</code>: Thrown when you pass a non-object value to a function which expects an object as a paramter</li>
-<li><code>OverwriteModelError</code>: Thrown when you call <a href="api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> to re-define a model that was already defined.</li>
-<li><code>ParallelSaveError</code>: Thrown when you call <a href="api.html#model_Model-save"><code>save()</code></a> on a document when the same document instance is already saving.</li>
-<li><code>StrictModeError</code>: Thrown when you set a path that isn't the schema and <a href="guide.html#strict">strict mode</a> is set to <code>throw</code>.</li>
-<li><code>VersionError</code>: Thrown when the <a href="guide.html#versionKey">document is out of sync</a></li>
-</ul>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/model.html b/docs/api/model.html
deleted file mode 100644
index 6919734362e..00000000000
--- a/docs/api/model.html
+++ /dev/null
@@ -1,1329 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Model</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title" style="font-weight: bold"><a href="model.html">Model</a></div><ul class="nav-item-sub"><li><a href="#model_Model">Model()</a></li><li><a href="#model_Model.aggregate">Model.aggregate()</a></li><li><a href="#model_Model.bulkWrite">Model.bulkWrite()</a></li><li><a href="#model_Model.count">Model.count()</a></li><li><a href="#model_Model.countDocuments">Model.countDocuments()</a></li><li><a href="#model_Model.create">Model.create()</a></li><li><a href="#model_Model.createCollection">Model.createCollection()</a></li><li><a href="#model_Model.createIndexes">Model.createIndexes()</a></li><li><a href="#model_Model.deleteMany">Model.deleteMany()</a></li><li><a href="#model_Model.deleteOne">Model.deleteOne()</a></li><li><a href="#model_Model.discriminator">Model.discriminator()</a></li><li><a href="#model_Model.distinct">Model.distinct()</a></li><li><a href="#model_Model.ensureIndexes">Model.ensureIndexes()</a></li><li><a href="#model_Model.estimatedDocumentCount">Model.estimatedDocumentCount()</a></li><li><a href="#model_Model-events">Model.events</a></li><li><a href="#model_Model.exists">Model.exists()</a></li><li><a href="#model_Model.find">Model.find()</a></li><li><a href="#model_Model.findById">Model.findById()</a></li><li><a href="#model_Model.findByIdAndDelete">Model.findByIdAndDelete()</a></li><li><a href="#model_Model.findByIdAndRemove">Model.findByIdAndRemove()</a></li><li><a href="#model_Model.findByIdAndUpdate">Model.findByIdAndUpdate()</a></li><li><a href="#model_Model.findOne">Model.findOne()</a></li><li><a href="#model_Model.findOneAndDelete">Model.findOneAndDelete()</a></li><li><a href="#model_Model.findOneAndRemove">Model.findOneAndRemove()</a></li><li><a href="#model_Model.findOneAndReplace">Model.findOneAndReplace()</a></li><li><a href="#model_Model.findOneAndUpdate">Model.findOneAndUpdate()</a></li><li><a href="#model_Model.geoSearch">Model.geoSearch()</a></li><li><a href="#model_Model.hydrate">Model.hydrate()</a></li><li><a href="#model_Model.init">Model.init()</a></li><li><a href="#model_Model.insertMany">Model.insertMany()</a></li><li><a href="#model_Model.listIndexes">Model.listIndexes()</a></li><li><a href="#model_Model.mapReduce">Model.mapReduce()</a></li><li><a href="#model_Model.populate">Model.populate()</a></li><li><a href="#model_Model-$where">Model.prototype.$where</a></li><li><a href="#model_Model-$where">Model.prototype.$where()</a></li><li><a href="#model_Model-base">Model.prototype.base</a></li><li><a href="#model_Model-baseModelName">Model.prototype.baseModelName</a></li><li><a href="#model_Model-collection">Model.prototype.collection</a></li><li><a href="#model_Model-db">Model.prototype.db</a></li><li><a href="#model_Model-delete">Model.prototype.delete</a></li><li><a href="#model_Model-deleteOne">Model.prototype.deleteOne()</a></li><li><a href="#model_Model-discriminators">Model.prototype.discriminators</a></li><li><a href="#model_Model-increment">Model.prototype.increment()</a></li><li><a href="#model_Model-model">Model.prototype.model()</a></li><li><a href="#model_Model-modelName">Model.prototype.modelName</a></li><li><a href="#model_Model-remove">Model.prototype.remove()</a></li><li><a href="#model_Model-save">Model.prototype.save()</a></li><li><a href="#model_Model-schema">Model.prototype.schema</a></li><li><a href="#model_Model.remove">Model.remove()</a></li><li><a href="#model_Model.replaceOne">Model.replaceOne()</a></li><li><a href="#model_Model.startSession">Model.startSession()</a></li><li><a href="#model_Model.syncIndexes">Model.syncIndexes()</a></li><li><a href="#model_Model.translateAliases">Model.translateAliases()</a></li><li><a href="#model_Model.update">Model.update()</a></li><li><a href="#model_Model.updateMany">Model.updateMany()</a></li><li><a href="#model_Model.updateOne">Model.updateOne()</a></li><li><a href="#model_Model.watch">Model.watch()</a></li><li><a href="#model_Model.where">Model.where()</a></li><li><a href="#model_Model.inspect">function Object() { [native code] }.prototype.inspect()</a></li></ul></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#model_Model">Model()</a></li><li><a href="#model_Model.aggregate">Model.aggregate()</a></li><li><a href="#model_Model.bulkWrite">Model.bulkWrite()</a></li><li><a href="#model_Model.count">Model.count()</a></li><li><a href="#model_Model.countDocuments">Model.countDocuments()</a></li><li><a href="#model_Model.create">Model.create()</a></li><li><a href="#model_Model.createCollection">Model.createCollection()</a></li><li><a href="#model_Model.createIndexes">Model.createIndexes()</a></li><li><a href="#model_Model.deleteMany">Model.deleteMany()</a></li><li><a href="#model_Model.deleteOne">Model.deleteOne()</a></li><li><a href="#model_Model.discriminator">Model.discriminator()</a></li><li><a href="#model_Model.distinct">Model.distinct()</a></li><li><a href="#model_Model.ensureIndexes">Model.ensureIndexes()</a></li><li><a href="#model_Model.estimatedDocumentCount">Model.estimatedDocumentCount()</a></li><li><a href="#model_Model-events">Model.events</a></li><li><a href="#model_Model.exists">Model.exists()</a></li><li><a href="#model_Model.find">Model.find()</a></li><li><a href="#model_Model.findById">Model.findById()</a></li><li><a href="#model_Model.findByIdAndDelete">Model.findByIdAndDelete()</a></li><li><a href="#model_Model.findByIdAndRemove">Model.findByIdAndRemove()</a></li><li><a href="#model_Model.findByIdAndUpdate">Model.findByIdAndUpdate()</a></li><li><a href="#model_Model.findOne">Model.findOne()</a></li><li><a href="#model_Model.findOneAndDelete">Model.findOneAndDelete()</a></li><li><a href="#model_Model.findOneAndRemove">Model.findOneAndRemove()</a></li><li><a href="#model_Model.findOneAndReplace">Model.findOneAndReplace()</a></li><li><a href="#model_Model.findOneAndUpdate">Model.findOneAndUpdate()</a></li><li><a href="#model_Model.geoSearch">Model.geoSearch()</a></li><li><a href="#model_Model.hydrate">Model.hydrate()</a></li><li><a href="#model_Model.init">Model.init()</a></li><li><a href="#model_Model.insertMany">Model.insertMany()</a></li><li><a href="#model_Model.listIndexes">Model.listIndexes()</a></li><li><a href="#model_Model.mapReduce">Model.mapReduce()</a></li><li><a href="#model_Model.populate">Model.populate()</a></li><li><a href="#model_Model-$where">Model.prototype.$where</a></li><li><a href="#model_Model-$where">Model.prototype.$where()</a></li><li><a href="#model_Model-base">Model.prototype.base</a></li><li><a href="#model_Model-baseModelName">Model.prototype.baseModelName</a></li><li><a href="#model_Model-collection">Model.prototype.collection</a></li><li><a href="#model_Model-db">Model.prototype.db</a></li><li><a href="#model_Model-delete">Model.prototype.delete</a></li><li><a href="#model_Model-deleteOne">Model.prototype.deleteOne()</a></li><li><a href="#model_Model-discriminators">Model.prototype.discriminators</a></li><li><a href="#model_Model-increment">Model.prototype.increment()</a></li><li><a href="#model_Model-model">Model.prototype.model()</a></li><li><a href="#model_Model-modelName">Model.prototype.modelName</a></li><li><a href="#model_Model-remove">Model.prototype.remove()</a></li><li><a href="#model_Model-save">Model.prototype.save()</a></li><li><a href="#model_Model-schema">Model.prototype.schema</a></li><li><a href="#model_Model.remove">Model.remove()</a></li><li><a href="#model_Model.replaceOne">Model.replaceOne()</a></li><li><a href="#model_Model.startSession">Model.startSession()</a></li><li><a href="#model_Model.syncIndexes">Model.syncIndexes()</a></li><li><a href="#model_Model.translateAliases">Model.translateAliases()</a></li><li><a href="#model_Model.update">Model.update()</a></li><li><a href="#model_Model.updateMany">Model.updateMany()</a></li><li><a href="#model_Model.updateOne">Model.updateOne()</a></li><li><a href="#model_Model.watch">Model.watch()</a></li><li><a href="#model_Model.where">Model.where()</a></li><li><a href="#model_Model.inspect">function Object() { [native code] }.prototype.inspect()</a></li></ul><hr class="separate-api-elements"><h3 id="model_Model"><a href="#model_Model">Model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> values for initial set</li><li class="param">optional
-<span class="method-type">&laquo;[fields]&raquo;</span> object containing the fields that were selected in the query which returned this document. You do <strong>not</strong> need to set this parameter to ensure Mongoose handles your <a href="./api.html#query_Query-select">query projection</a>.</li></ul><div><p>A Model is a class that's your primary tool for interacting with MongoDB. An instance of a Model is called a <a href="./api.html#Document">Document</a>.</p>
-
-<p>In Mongoose, the term "Model" refers to subclasses of the <code>mongoose.Model</code> class. You should not use the <code>mongoose.Model</code> class directly. The <a href="./api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> and <a href="./api.html#connection_Connection-model"><code>connection.model()</code></a> functions create subclasses of <code>mongoose.Model</code> as shown below.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// `UserModel` is a "Model", a subclass of `mongoose.Model`.</span>
-<span class="hljs-keyword">const</span> UserModel = mongoose.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-
-<span class="hljs-comment">// You can use a Model to create new documents using `new`:</span>
-<span class="hljs-keyword">const</span> userDoc = <span class="hljs-keyword">new</span> UserModel({ name: <span class="hljs-string">'Foo'</span> });
-<span class="hljs-keyword">await</span> userDoc.save();
-
-<span class="hljs-comment">// You also use a model to create queries:</span>
-<span class="hljs-keyword">const</span> userFromDb = <span class="hljs-keyword">await</span> UserModel.findOne({ name: <span class="hljs-string">'Foo'</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.aggregate"><a href="#model_Model.aggregate">Model.aggregate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[pipeline]
-<span class="method-type">&laquo;Array&raquo;</span> aggregation pipeline as an array of objects</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Aggregate&raquo;</span> </li></ul><div><p>Performs <a href="http://docs.mongodb.org/manual/applications/aggregation/">aggregations</a> on the models collection.</p>
-
-<p>If a <code>callback</code> is passed, the <code>aggregate</code> is executed and a <code>Promise</code> is returned. If a callback is not passed, the <code>aggregate</code> itself is returned.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>aggregate()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Find the max balance of all accounts</span>
-Users.aggregate([
-  { $group: { _id: <span class="hljs-literal">null</span>, maxBalance: { $max: <span class="hljs-string">'$balance'</span> }}},
-  { $project: { _id: <span class="hljs-number">0</span>, maxBalance: <span class="hljs-number">1</span> }}
-]).
-then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">res</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(res); <span class="hljs-comment">// [ { maxBalance: 98000 } ]</span>
-});
-
-<span class="hljs-comment">// Or use the aggregation pipeline builder.</span>
-Users.aggregate().
-  group({ _id: <span class="hljs-literal">null</span>, maxBalance: { $max: <span class="hljs-string">'$balance'</span> } }).
-  project(<span class="hljs-string">'-id maxBalance'</span>).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, res</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-    <span class="hljs-built_in">console</span>.log(res); <span class="hljs-comment">// [ { maxBalance: 98 } ]</span>
-  });</code></pre>
-
-<h4>NOTE:</h4>
-
-<ul>
-<li>Arguments are not cast to the model's schema because <code>$project</code> operators allow redefining the "shape" of the documents at any stage of the pipeline, which may leave documents in an incompatible format.</li>
-<li>The documents returned are plain javascript objects, not mongoose documents (since any shape of document can be returned).</li>
-<li>Requires MongoDB >= 2.1</li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.bulkWrite"><a href="#model_Model.bulkWrite">Model.bulkWrite()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ops
-<span class="method-type">&laquo;Array&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[ops.insertOne.document]
-<span class="method-type">&laquo;Object&raquo;</span> The document to insert</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Update the first document that matches this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.update]
-<span class="method-type">&laquo;Object&raquo;</span> An object containing <a href="https://docs.mongodb.com/manual/reference/operator/update/">update operators</a></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, insert a doc if none match</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.collation]
-<span class="method-type">&laquo;Object&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations">MongoDB collation</a> to use</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateOne.arrayFilters]
-<span class="method-type">&laquo;Array&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-array-filters.html">array filters</a> used in <code>update</code></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Update all the documents that match this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.update]
-<span class="method-type">&laquo;Object&raquo;</span> An object containing <a href="https://docs.mongodb.com/manual/reference/operator/update/">update operators</a></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, insert a doc if no documents match <code>filter</code></li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.collation]
-<span class="method-type">&laquo;Object&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations">MongoDB collation</a> to use</li></ul><ul style="margin-top: 0.5em"><li>[opts.updateMany.arrayFilters]
-<span class="method-type">&laquo;Array&raquo;</span> The <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-array-filters.html">array filters</a> used in <code>update</code></li></ul><ul style="margin-top: 0.5em"><li>[opts.deleteOne.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Delete the first document that matches this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.deleteMany.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Delete all documents that match this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.replaceOne.filter]
-<span class="method-type">&laquo;Object&raquo;</span> Replace the first document that matches this filter</li></ul><ul style="margin-top: 0.5em"><li>[opts.replaceOne.replacement]
-<span class="method-type">&laquo;Object&raquo;</span> The replacement document</li></ul><ul style="margin-top: 0.5em"><li>[opts.replaceOne.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, insert a doc if no documents match <code>filter</code></li></ul><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.ordered=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, execute writes in order and stop at the first error. If false, execute writes in parallel and continue until all writes have either succeeded or errored.</li></ul><ul style="margin-top: 0.5em"><li>[options.session=null]
-<span class="method-type">&laquo;ClientSession&raquo;</span> The session associated with this bulk write. See <a href="/docs/transactions.html">transactions docs</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.w=1]
-<span class="method-type">&laquo;String|number&raquo;</span> The <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a>. See <a href="/docs/api.html#query_Query-w"><code>Query#w()</code></a> for more information.</li></ul><ul style="margin-top: 0.5em"><li>[options.wtimeout=null]
-<span class="method-type">&laquo;number&raquo;</span> The <a href="https://docs.mongodb.com/manual/reference/write-concern/#wtimeout">write concern timeout</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.j=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> If false, disable <a href="https://docs.mongodb.com/manual/reference/write-concern/#j-option">journal acknowledgement</a></li></ul><ul style="margin-top: 0.5em"><li>[options.bypassDocumentValidation=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, disable <a href="https://docs.mongodb.com/manual/core/schema-validation/">MongoDB server-side schema validation</a> for all writes in this bulk.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback <code>function(error, bulkWriteOpResult) {}</code></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> resolves to a <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult"><code>BulkWriteOpResult</code></a> if the operation succeeds</li></ul><div><p>Sends multiple <code>insertOne</code>, <code>updateOne</code>, <code>updateMany</code>, <code>replaceOne</code>, <code>deleteOne</code>, and/or <code>deleteMany</code> operations to the MongoDB server in one command. This is faster than sending multiple independent operations (like) if you use <code>create()</code>) because with <code>bulkWrite()</code> there is only one round trip to MongoDB.</p>
-
-<p>Mongoose will perform casting on all operations you provide.</p>
-
-<p>This function does <strong>not</strong> trigger any middleware, not <code>save()</code> nor <code>update()</code>. If you need to trigger <code>save()</code> middleware for every document use <a href="http://mongoosejs.com/docs/api.html#model_Model.create"><code>create()</code></a> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character.bulkWrite([
-  {
-    insertOne: {
-      <span class="hljs-built_in">document</span>: {
-        name: <span class="hljs-string">'Eddard Stark'</span>,
-        title: <span class="hljs-string">'Warden of the North'</span>
-      }
-    }
-  },
-  {
-    updateOne: {
-      filter: { name: <span class="hljs-string">'Eddard Stark'</span> },
-      <span class="hljs-comment">// If you were using the MongoDB driver directly, you'd need to do</span>
-      <span class="hljs-comment">// `update: { $set: { title: ... } }` but mongoose adds $set for</span>
-      <span class="hljs-comment">// you.</span>
-      update: { title: <span class="hljs-string">'Hand of the King'</span> }
-    }
-  },
-  {
-    deleteOne: {
-      {
-        filter: { name: <span class="hljs-string">'Eddard Stark'</span> }
-      }
-    }
-  }
-]).then(res =&gt; {
- <span class="hljs-comment">// Prints "1 1 1"</span>
- <span class="hljs-built_in">console</span>.log(res.insertedCount, res.modifiedCount, res.deletedCount);
-});</code></pre>
-
-<p>The <a href="https://docs.mongodb.com/manual/reference/method/db.collection.bulkWrite/#db.collection.bulkWrite">supported operations</a> are:</p>
-
-<ul>
-<li><code>insertOne</code></li>
-<li><code>updateOne</code></li>
-<li><code>updateMany</code></li>
-<li><code>deleteOne</code></li>
-<li><code>deleteMany</code></li>
-<li><code>replaceOne</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.count"><a href="#model_Model.count">Model.count()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Counts number of documents that match <code>filter</code> in a database collection.</p>
-
-<p>This method is deprecated. If you want to count the number of documents in a collection, e.g. <code>count({})</code>, use the <a href="/docs/api.html#model_Model.estimatedDocumentCount"><code>estimatedDocumentCount()</code> function</a> instead. Otherwise, use the <a href="/docs/api.html#model_Model.countDocuments"><code>countDocuments()</code></a> function instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Adventure.count({ type: <span class="hljs-string">'jungle'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d jungle adventures'</span>, count);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.countDocuments"><a href="#model_Model.countDocuments">Model.countDocuments()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Counts number of documents matching <code>filter</code> in a database collection.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Adventure.countDocuments({ type: <span class="hljs-string">'jungle'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d jungle adventures'</span>, count);
-});</code></pre>
-
-<p>If you want to count all documents in a large collection, use the <a href="/docs/api.html#model_Model.estimatedDocumentCount"><code>estimatedDocumentCount()</code> function</a> instead. If you call <code>countDocuments({})</code>, MongoDB will always execute a full collection scan and <strong>not</strong> use any indexes.</p>
-
-<p>The <code>countDocuments()</code> function is similar to <code>count()</code>, but there are a <a href="https://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments">few operators that <code>countDocuments()</code> does not support</a>. Below are the operators that <code>count()</code> supports but <code>countDocuments()</code> does not, and the suggested replacement:</p>
-
-<ul>
-<li><code>$where</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/expr/"><code>$expr</code></a></li>
-<li><code>$near</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/center/#op._S_center"><code>$center</code></a></li>
-<li><code>$nearSphere</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/centerSphere/#op._S_centerSphere"><code>$centerSphere</code></a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.create"><a href="#model_Model.create">Model.create()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">docs
-<span class="method-type">&laquo;Array|Object&raquo;</span> Documents to insert, as a spread or array</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Options passed down to <code>save()</code>. To specify <code>options</code>, <code>docs</code> <strong>must</strong> be an array, not a spread.</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Shortcut for saving one or more documents to the database. <code>MyModel.create(docs)</code> does <code>new MyModel(doc).save()</code> for every doc in docs.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>save()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// pass a spread of docs and a callback</span>
-Candy.create({ type: <span class="hljs-string">'jelly bean'</span> }, { type: <span class="hljs-string">'snickers'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, jellybean, snickers</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-comment">// ...</span>
-});
-
-<span class="hljs-comment">// pass an array of docs</span>
-<span class="hljs-keyword">var</span> array = [{ type: <span class="hljs-string">'jelly bean'</span> }, { type: <span class="hljs-string">'snickers'</span> }];
-Candy.create(array, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, candies</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-comment">// ...</span>
-
-  <span class="hljs-keyword">var</span> jellybean = candies[<span class="hljs-number">0</span>];
-  <span class="hljs-keyword">var</span> snickers = candies[<span class="hljs-number">1</span>];
-  <span class="hljs-comment">// ...</span>
-});
-
-<span class="hljs-comment">// callback is optional; use the returned promise if you like:</span>
-<span class="hljs-keyword">var</span> promise = Candy.create({ type: <span class="hljs-string">'jawbreaker'</span> });
-promise.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">jawbreaker</span>) </span>{
-  <span class="hljs-comment">// ...</span>
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.createCollection"><a href="#model_Model.createCollection">Model.createCollection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Db.html#createCollection">MongoDB driver docs</a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Create the collection for this model. By default, if no indexes are specified, mongoose will not create the collection for the model until any documents are created. Use this method to create the collection explicitly.</p>
-
-<p>Note 1: You may need to call this before starting a transaction See <a href='https://docs.mongodb.com/manual/core/transactions/#transactions-and-operations'>https://docs.mongodb.com/manual/core/transactions/#transactions-and-operations</a></p>
-
-<p>Note 2: You don't have to call this if your schema contains index or unique field. In that case, just use <code>Model.init()</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> userSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> })
-<span class="hljs-keyword">var</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-User.createCollection().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">collection</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Collection is created!'</span>);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.createIndexes"><a href="#model_Model.createIndexes">Model.createIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> internal options</li><li class="param">[cb]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Similar to <code>ensureIndexes()</code>, except for it uses the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex"><code>createIndex</code></a> function.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.deleteMany"><a href="#model_Model.deleteMany">Model.deleteMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Deletes all of the documents that match <code>conditions</code> from the collection. Behaves like <code>remove()</code>, but deletes all documents that match <code>conditions</code> regardless of the <code>single</code> option.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{});</code></pre>
-
-<h4>Note:</h4>
-
-<p>Like <code>Model.remove()</code>, this function does <strong>not</strong> trigger <code>pre('remove')</code> or <code>post('remove')</code> hooks.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.deleteOne"><a href="#model_Model.deleteOne">Model.deleteOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Deletes the first document that matches <code>conditions</code> from the collection. Behaves like <code>remove()</code>, but deletes at most one document regardless of the <code>single</code> option.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{});</code></pre>
-
-<h4>Note:</h4>
-
-<p>Like <code>Model.remove()</code>, this function does <strong>not</strong> trigger <code>pre('remove')</code> or <code>post('remove')</code> hooks.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.discriminator"><a href="#model_Model.discriminator">Model.discriminator()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> discriminator model name</li><li class="param">schema
-<span class="method-type">&laquo;Schema&raquo;</span> discriminator model schema</li><li class="param">value
-<span class="method-type">&laquo;String&raquo;</span> the string stored in the <code>discriminatorKey</code> property</li></ul><div><p>Adds a discriminator type.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">BaseSchema</span>(<span class="hljs-params"></span>) </span>{
-  Schema.apply(<span class="hljs-keyword">this</span>, <span class="hljs-built_in">arguments</span>);
-
-  <span class="hljs-keyword">this</span>.add({
-    name: <span class="hljs-built_in">String</span>,
-    createdAt: <span class="hljs-built_in">Date</span>
-  });
-}
-util.inherits(BaseSchema, Schema);
-
-<span class="hljs-keyword">var</span> PersonSchema = <span class="hljs-keyword">new</span> BaseSchema();
-<span class="hljs-keyword">var</span> BossSchema = <span class="hljs-keyword">new</span> BaseSchema({ department: <span class="hljs-built_in">String</span> });
-
-<span class="hljs-keyword">var</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, PersonSchema);
-<span class="hljs-keyword">var</span> Boss = Person.discriminator(<span class="hljs-string">'Boss'</span>, BossSchema);
-<span class="hljs-keyword">new</span> Boss().__t; <span class="hljs-comment">// "Boss". `__t` is the default `discriminatorKey`</span>
-
-<span class="hljs-keyword">var</span> employeeSchema = <span class="hljs-keyword">new</span> Schema({ boss: ObjectId });
-<span class="hljs-keyword">var</span> Employee = Person.discriminator(<span class="hljs-string">'Employee'</span>, employeeSchema, <span class="hljs-string">'staff'</span>);
-<span class="hljs-keyword">new</span> Employee().__t; <span class="hljs-comment">// "staff" because of 3rd argument above</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.distinct"><a href="#model_Model.distinct">Model.distinct()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">field
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> optional</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Creates a Query for a <code>distinct</code> operation.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<h4>Example</h4>
-
-<pre><code>Link.distinct(<span class="hljs-string">'url'</span>, { clicks: {$gt: <span class="hljs-number">100</span>}}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, result</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-
-  assert(<span class="hljs-built_in">Array</span>.isArray(result));
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'unique urls with more than 100 clicks'</span>, result);
-})
-
-<span class="hljs-keyword">var</span> query = Link.distinct(<span class="hljs-string">'url'</span>);
-query.exec(callback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.ensureIndexes"><a href="#model_Model.ensureIndexes">Model.ensureIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> internal options</li><li class="param">[cb]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Sends <code>createIndex</code> commands to mongo for each index declared in the schema. The <code>createIndex</code> commands are sent in series.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Event.ensureIndexes(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-});</code></pre>
-
-<p>After completion, an <code>index</code> event is emitted on this <code>Model</code> passing an error if one occurred.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> Schema({ thing: { type: <span class="hljs-string">'string'</span>, unique: <span class="hljs-literal">true</span> }})
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'Event'</span>, eventSchema);
-
-Event.on(<span class="hljs-string">'index'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-built_in">console</span>.error(err); <span class="hljs-comment">// error occurred during index creation</span>
-})</code></pre>
-
-<p><em>NOTE: It is not recommended that you run this in production. Index creation may impact database performance depending on your load. Use with caution.</em></p>  </div><hr class="separate-api-elements"><h3 id="model_Model.estimatedDocumentCount"><a href="#model_Model.estimatedDocumentCount">Model.estimatedDocumentCount()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Estimates the number of documents in the MongoDB collection. Faster than using <code>countDocuments()</code> for large collections because <code>estimatedDocumentCount()</code> uses collection metadata rather than scanning the entire collection.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> numAdventures = Adventure.estimatedDocumentCount();</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-events"><a href="#model_Model-events">Model.events</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Event emitter that reports any errors that occurred. Useful for global error handling.</p>
-
-<h4>Example:</h4>
-
-<pre><code>MyModel.events.on(<span class="hljs-string">'error'</span>, err =&gt; <span class="hljs-built_in">console</span>.log(err.message));
-
-<span class="hljs-comment">// Prints a 'CastError' because of the above handler</span>
-<span class="hljs-keyword">await</span> MyModel.findOne({ _id: <span class="hljs-string">'notanid'</span> }).catch(noop);</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.exists"><a href="#model_Model.exists">Model.exists()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Returns true if at least one document exists in the database that matches the given <code>filter</code>, and false otherwise.</p>
-
-<p>Under the hood, <code>MyModel.exists({ answer: 42 })</code> is equivalent to <code>MyModel.findOne({ answer: 42 }).select({ _id: 1 }).lean().then(doc => !!doc)</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> Character.deleteMany({});
-<span class="hljs-keyword">await</span> Character.create({ name: <span class="hljs-string">'Jean-Luc Picard'</span> });
-
-<span class="hljs-keyword">await</span> Character.exists({ name: <span class="hljs-regexp">/picard/i</span> }); <span class="hljs-comment">// true</span>
-<span class="hljs-keyword">await</span> Character.exists({ name: <span class="hljs-regexp">/riker/i</span> }); <span class="hljs-comment">// false</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOne()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.find"><a href="#model_Model.find">Model.find()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[projection]
-<span class="method-type">&laquo;Object|String&raquo;</span> optional fields to return, see <a href="#query_Query-select"><code>Query.prototype.select()</code></a></li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Finds documents</p>
-
-<p>The <code>conditions</code> are cast to their respective SchemaTypes before the command is sent.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// named john and at least 18</span>
-MyModel.find({ name: <span class="hljs-string">'john'</span>, age: { $gte: <span class="hljs-number">18</span> }});
-
-<span class="hljs-comment">// executes, passing results to callback</span>
-MyModel.find({ name: <span class="hljs-string">'john'</span>, age: { $gte: <span class="hljs-number">18</span> }}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});
-
-<span class="hljs-comment">// executes, name LIKE john and only selecting the "name" and "friends" fields</span>
-MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-string">'name friends'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{ })
-
-<span class="hljs-comment">// passing options</span>
-MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> })
-
-<span class="hljs-comment">// passing options and executes</span>
-MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});
-
-<span class="hljs-comment">// executing a query explicitly</span>
-<span class="hljs-keyword">var</span> query = MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> })
-query.exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});
-
-<span class="hljs-comment">// using the promise returned from executing a query</span>
-<span class="hljs-keyword">var</span> query = MyModel.find({ name: <span class="hljs-regexp">/john/i</span> }, <span class="hljs-literal">null</span>, { skip: <span class="hljs-number">10</span> });
-<span class="hljs-keyword">var</span> promise = query.exec();
-promise.addBack(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findById"><a href="#model_Model.findById">Model.findById()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|String|Number&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[projection]
-<span class="method-type">&laquo;Object|String&raquo;</span> optional fields to return, see <a href="#query_Query-select"><code>Query.prototype.select()</code></a></li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Finds a single document by its _id field. <code>findById(id)</code> is almost* equivalent to <code>findOne({ _id: id })</code>. If you want to query by a document's <code>_id</code>, use <code>findById()</code> instead of <code>findOne()</code>.</p>
-
-<p>The <code>id</code> is cast based on the Schema before sending the command.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOne()</code></li>
-</ul>
-
-<p>* Except for how it treats <code>undefined</code>. If you use <code>findOne()</code>, you'll see that <code>findOne(undefined)</code> and <code>findOne({ _id: undefined })</code> are equivalent to <code>findOne({})</code> and return arbitrary documents. However, mongoose translates <code>findById(undefined)</code> into <code>findOne({ _id: null })</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// find adventure by id and execute</span>
-Adventure.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findById(id).exec(callback);
-
-<span class="hljs-comment">// select only the adventures name and length</span>
-Adventure.findById(id, <span class="hljs-string">'name length'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findById(id, <span class="hljs-string">'name length'</span>).exec(callback);
-
-<span class="hljs-comment">// include all properties except for `length`</span>
-Adventure.findById(id, <span class="hljs-string">'-length'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// passing options (in this case return the raw js objects, not mongoose documents by passing `lean`</span>
-Adventure.findById(id, <span class="hljs-string">'name'</span>, { lean: <span class="hljs-literal">true</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findById(id, <span class="hljs-string">'name'</span>).lean().exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findByIdAndDelete"><a href="#model_Model.findByIdAndDelete">Model.findByIdAndDelete()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|Number|String&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a MongoDB <code>findOneAndDelete()</code> command by a document's _id field. In other words, <code>findByIdAndDelete(id)</code> is a shorthand for <code>findOneAndDelete({ _id: id })</code>.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndDelete()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.findByIdAndRemove"><a href="#model_Model.findByIdAndRemove">Model.findByIdAndRemove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|Number|String&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a mongodb findAndModify remove command by a document's _id field. <code>findByIdAndRemove(id, ...)</code> is equivalent to <code>findOneAndRemove({ _id: id }, ...)</code>.</p>
-
-<p>Finds a matching document, removes it, passing the found document (if any) to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndRemove()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findByIdAndRemove(id, options, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndRemove(id, options)  <span class="hljs-comment">// return Query</span>
-A.findByIdAndRemove(id, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndRemove(id) <span class="hljs-comment">// returns Query</span>
-A.findByIdAndRemove()           <span class="hljs-comment">// returns Query</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findByIdAndUpdate"><a href="#model_Model.findByIdAndUpdate">Model.findByIdAndUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">id
-<span class="method-type">&laquo;Object|Number|String&raquo;</span> value of <code>_id</code> to query by</li><li class="param">[update]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="/docs/api.html#query_Query-lean"><code>Query.lean()</code></a> and the <a href="/docs/tutorials/lean.html">Mongoose lean tutorial</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issues a mongodb findAndModify update command by a document's _id field. <code>findByIdAndUpdate(id, ...)</code> is equivalent to <code>findOneAndUpdate({ _id: id }, ...)</code>.</p>
-
-<p>Finds a matching document, updates it according to the <code>update</code> arg, passing any <code>options</code>, and returns the found document (if any) to the callback. The query executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndUpdate()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>new</code>: bool - true to return the modified document rather than the original. defaults to false</li>
-<li><code>upsert</code>: bool - creates the object if it doesn't exist. defaults to false.</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findByIdAndUpdate(id, update, options, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndUpdate(id, update, options)  <span class="hljs-comment">// returns Query</span>
-A.findByIdAndUpdate(id, update, callback) <span class="hljs-comment">// executes</span>
-A.findByIdAndUpdate(id, update)           <span class="hljs-comment">// returns Query</span>
-A.findByIdAndUpdate()                     <span class="hljs-comment">// returns Query</span></code></pre>
-
-<h4>Note:</h4>
-
-<p>All top level update keys which are not <code>atomic</code> operation names are treated as set operations:</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findByIdAndUpdate(id, { name: <span class="hljs-string">'jason bourne'</span> }, options, callback)
-
-<span class="hljs-comment">// is sent as</span>
-Model.findByIdAndUpdate(id, { $set: { name: <span class="hljs-string">'jason bourne'</span> }}, options, callback)</code></pre>
-
-<p>This helps prevent accidentally overwriting your document with <code>{ name: 'jason bourne' }</code>.</p>
-
-<h4>Note:</h4>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findOne"><a href="#model_Model.findOne">Model.findOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[projection]
-<span class="method-type">&laquo;Object|String&raquo;</span> optional fields to return, see <a href="#query_Query-select"><code>Query.prototype.select()</code></a></li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Finds one document.</p>
-
-<p>The <code>conditions</code> are cast to their respective SchemaTypes before the command is sent.</p>
-
-<p><em>Note:</em> <code>conditions</code> is optional, and if <code>conditions</code> is null or undefined, mongoose will send an empty <code>findOne</code> command to MongoDB, which will return an arbitrary document. If you're querying by <code>_id</code>, use <code>findById()</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// find one iphone adventures - iphone adventures??</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// select only the adventures name</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, adventure</span>) </span>{});
-
-<span class="hljs-comment">// specify options, in this case lean</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>, { lean: <span class="hljs-literal">true</span> }, callback);
-
-<span class="hljs-comment">// same as above</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }, <span class="hljs-string">'name'</span>, { lean: <span class="hljs-literal">true</span> }).exec(callback);
-
-<span class="hljs-comment">// chaining findOne queries (same as above)</span>
-Adventure.findOne({ type: <span class="hljs-string">'iphone'</span> }).select(<span class="hljs-string">'name'</span>).lean().exec(callback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndDelete"><a href="#model_Model.findOneAndDelete">Model.findOneAndDelete()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a MongoDB <code>findOneAndDelete()</code> command.</p>
-
-<p>Finds a matching document, removes it, and passes the found document (if any) to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndDelete()</code></li>
-</ul>
-
-<p>This function differs slightly from <code>Model.findOneAndRemove()</code> in that <code>findOneAndRemove()</code> becomes a <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/">MongoDB <code>findAndModify()</code> command</a>, as opposed to a <code>findOneAndDelete()</code> command. For most mongoose use cases, this distinction is purely pedantic. You should use <code>findOneAndDelete()</code> unless you have a good reason not to.</p>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>projection</code>: like select, it determines which fields to return, ex. <code>{ projection: { _id: 0 } }</code></li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndDelete(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndDelete(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.findOneAndDelete(conditions, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndDelete(conditions) <span class="hljs-comment">// returns Query</span>
-A.findOneAndDelete()           <span class="hljs-comment">// returns Query</span></code></pre>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndRemove"><a href="#model_Model.findOneAndRemove">Model.findOneAndRemove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a mongodb findAndModify remove command.</p>
-
-<p>Finds a matching document, removes it, passing the found document (if any) to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndRemove()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>projection</code>: like select, it determines which fields to return, ex. <code>{ projection: { _id: 0 } }</code></li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndRemove(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndRemove(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.findOneAndRemove(conditions, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndRemove(conditions) <span class="hljs-comment">// returns Query</span>
-A.findOneAndRemove()           <span class="hljs-comment">// returns Query</span></code></pre>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndReplace"><a href="#model_Model.findOneAndReplace">Model.findOneAndReplace()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> Replace the first document that matches this filter</li><li class="param">[replacement]
-<span class="method-type">&laquo;Object&raquo;</span> Replace with this document</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="http://mongoosejs.com/docs/api.html#query_Query-lean"><code>Query.lean()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issue a MongoDB <code>findOneAndReplace()</code> command.</p>
-
-<p>Finds a matching document, replaces it with the provided doc, and passes the returned doc to the callback.</p>
-
-<p>Executes the query if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following query middleware.</p>
-
-<ul>
-<li><code>findOneAndReplace()</code></li>
-</ul>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>select</code>: sets the document fields to return</li>
-<li><code>projection</code>: like select, it determines which fields to return, ex. <code>{ projection: { _id: 0 } }</code></li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndReplace(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndReplace(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.findOneAndReplace(conditions, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndReplace(conditions) <span class="hljs-comment">// returns Query</span>
-A.findOneAndReplace()           <span class="hljs-comment">// returns Query</span></code></pre>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.findOneAndUpdate"><a href="#model_Model.findOneAndUpdate">Model.findOneAndUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[update]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="/docs/api.html#query_Query-lean"><code>Query.lean()</code></a> and <a href="/docs/tutorials/lean.html">the Mongoose lean tutorial</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Issues a mongodb findAndModify update command.</p>
-
-<p>Finds a matching document, updates it according to the <code>update</code> arg, passing any <code>options</code>, and returns the found document (if any) to the callback. The query executes if <code>callback</code> is passed else a Query object is returned.</p>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>new</code>: bool - if true, return the modified document rather than the original. defaults to false (changed in 4.0)</li>
-<li><code>upsert</code>: bool - creates the object if it doesn't exist. defaults to false.</li>
-<li><code>fields</code>: {Object|String} - Field selection. Equivalent to <code>.select(fields).findOneAndUpdate()</code></li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>strict</code>: overwrites the schema's <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a> for this update</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>A.findOneAndUpdate(conditions, update, options, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndUpdate(conditions, update, options)  <span class="hljs-comment">// returns Query</span>
-A.findOneAndUpdate(conditions, update, callback) <span class="hljs-comment">// executes</span>
-A.findOneAndUpdate(conditions, update)           <span class="hljs-comment">// returns Query</span>
-A.findOneAndUpdate()                             <span class="hljs-comment">// returns Query</span></code></pre>
-
-<h4>Note:</h4>
-
-<p>All top level update keys which are not <code>atomic</code> operation names are treated as set operations:</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = { name: <span class="hljs-string">'borne'</span> };
-Model.findOneAndUpdate(query, { name: <span class="hljs-string">'jason bourne'</span> }, options, callback)
-
-<span class="hljs-comment">// is sent as</span>
-Model.findOneAndUpdate(query, { $set: { name: <span class="hljs-string">'jason bourne'</span> }}, options, callback)</code></pre>
-
-<p>This helps prevent accidentally overwriting your document with <code>{ name: 'jason bourne' }</code>.</p>
-
-<h4>Note:</h4>
-
-<p>Values are cast to their appropriate types when using the findAndModify helpers. However, the below are not executed by default.</p>
-
-<ul>
-<li>defaults. Use the <code>setDefaultsOnInsert</code> option to override.</li>
-</ul>
-
-<p><code>findAndModify</code> helpers support limited validation. You can enable these by setting the <code>runValidators</code> options, respectively.</p>
-
-<p>If you need full-fledged validation, use the traditional approach of first retrieving the document.</p>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.geoSearch"><a href="#model_Model.geoSearch">Model.geoSearch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> an object that specifies the match condition (required)</li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> for the geoSearch, some (near, maxDistance) are required</li><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object|Boolean&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="/docs/api.html#query_Query-lean"><code>Query.lean()</code></a> and the <a href="/docs/tutorials/lean.html">Mongoose lean tutorial</a>.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Implements <code>$geoSearch</code> functionality for Mongoose</p>
-
-<p>This function does not trigger any middleware</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> options = { near: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> };
-Locations.geoSearch({ type : <span class="hljs-string">"house"</span> }, options, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, res</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(res);
-});</code></pre>
-
-<h4>Options:</h4>
-
-<ul>
-<li><code>near</code> {Array} x,y point to search for</li>
-<li><code>maxDistance</code> {Number} the maximum distance from the point near that a result can be</li>
-<li><code>limit</code> {Number} The maximum number of results to return</li>
-<li><code>lean</code> {Object|Boolean} return the raw object instead of the Mongoose Model</li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.hydrate"><a href="#model_Model.hydrate">Model.hydrate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Model&raquo;</span> document instance</li></ul><div><p>Shortcut for creating a new Document from existing raw data, pre-saved in the DB. The document returned has no paths marked as modified initially.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// hydrate previous data into a Mongoose document</span>
-<span class="hljs-keyword">var</span> mongooseCandy = Candy.hydrate({ _id: <span class="hljs-string">'54108337212ffb6d459f854c'</span>, type: <span class="hljs-string">'jelly bean'</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.init"><a href="#model_Model.init">Model.init()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>This function is responsible for building <a href="https://docs.mongodb.com/manual/indexes/">indexes</a>, unless <a href="http://mongoosejs.com/docs/guide.html#autoIndex"><code>autoIndex</code></a> is turned off.</p>
-
-<p>Mongoose calls this function automatically when a model is created using <a href="/docs/api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> or * <a href="/docs/api.html#connection_Connection-model"><code>connection.model()</code></a>, so you don't need to call it. This function is also idempotent, so you may call it to get back a promise that will resolve when your indexes are finished building as an alternative to <a href="/docs/guide.html#indexes"><code>MyModel.on('index')</code></a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> Schema({ thing: { type: <span class="hljs-string">'string'</span>, unique: <span class="hljs-literal">true</span> }})
-<span class="hljs-comment">// This calls `Event.init()` implicitly, so you don't need to call</span>
-<span class="hljs-comment">// `Event.init()` on your own.</span>
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'Event'</span>, eventSchema);
-
-Event.init().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">Event</span>) </span>{
-  <span class="hljs-comment">// You can also use `Event.on('index')` if you prefer event emitters</span>
-  <span class="hljs-comment">// over promises.</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Indexes are done building!'</span>);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.insertMany"><a href="#model_Model.insertMany">Model.insertMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">doc(s)
-<span class="method-type">&laquo;Array|Object|*&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#insertMany">mongodb driver options</a></li><li class="param">[options.ordered
-<span class="method-type">&laquo;Boolean&raquo;</span> = true] if true, will fail fast on the first error encountered. If false, will insert all the documents it can and report errors later. An <code>insertMany()</code> with <code>ordered = false</code> is called an &quot;unordered&quot; <code>insertMany()</code>.</li><li class="param">[options.rawResult
-<span class="method-type">&laquo;Boolean&raquo;</span> = false] if false, the returned promise resolves to the documents that passed mongoose document validation. If <code>true</code>, will return the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~insertWriteOpCallback">raw result from the MongoDB driver</a> with a <code>mongoose</code> property that contains <code>validationErrors</code> if this is an unordered <code>insertMany</code>.</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Shortcut for validating an array of documents and inserting them into MongoDB if they're all valid. This function is faster than <code>.create()</code> because it only sends one operation to the server, rather than one for each document.</p>
-
-<p>Mongoose always validates each document <strong>before</strong> sending <code>insertMany</code> to MongoDB. So if one document has a validation error, no documents will be saved, unless you set <a href="https://docs.mongodb.com/manual/reference/method/db.collection.insertMany/#error-handling">the <code>ordered</code> option to false</a>.</p>
-
-<p>This function does <strong>not</strong> trigger save middleware.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>insertMany()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> arr = [{ name: <span class="hljs-string">'Star Wars'</span> }, { name: <span class="hljs-string">'The Empire Strikes Back'</span> }];
-Movies.insertMany(arr, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, docs</span>) </span>{});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.listIndexes"><a href="#model_Model.listIndexes">Model.listIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[cb]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns <code>undefined</code> if callback is specified, returns a promise if no callback.</li></ul><div><p>Lists the indexes currently defined in MongoDB. This may or may not be the same as the indexes defined in your schema depending on whether you use the <a href="/docs/guide.html#autoIndex"><code>autoIndex</code> option</a> and if you build indexes manually.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.mapReduce"><a href="#model_Model.mapReduce">Model.mapReduce()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">o
-<span class="method-type">&laquo;Object&raquo;</span> an object specifying map-reduce options</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes a mapReduce command.</p>
-
-<p><code>o</code> is an object specifying all mapReduce options as well as the map and reduce functions. All options are delegated to the driver implementation. See <a href="http://mongodb.github.io/node-mongodb-native/api-generated/collection.html#mapreduce">node-mongodb-native mapReduce() documentation</a> for more detail about options.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> o = {};
-<span class="hljs-comment">// `map()` and `reduce()` are run on the MongoDB server, not Node.js,</span>
-<span class="hljs-comment">// these functions are converted to strings</span>
-o.map = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{ emit(<span class="hljs-keyword">this</span>.name, <span class="hljs-number">1</span>) };
-o.reduce = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">k, vals</span>) </span>{ <span class="hljs-keyword">return</span> vals.length };
-User.mapReduce(o, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, results</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(results)
-})</code></pre>
-
-<h4>Other options:</h4>
-
-<ul>
-<li><code>query</code> {Object} query filter object.</li>
-<li><code>sort</code> {Object} sort input objects using this key</li>
-<li><code>limit</code> {Number} max number of documents</li>
-<li><code>keeptemp</code> {Boolean, default:false} keep temporary data</li>
-<li><code>finalize</code> {Function} finalize function</li>
-<li><code>scope</code> {Object} scope variables exposed to map/reduce/finalize during execution</li>
-<li><code>jsMode</code> {Boolean, default:false} it is possible to make the execution stay in JS. Provided in MongoDB > 2.0.X</li>
-<li><code>verbose</code> {Boolean, default:false} provide statistics on job execution time.</li>
-<li><code>readPreference</code> {String}</li>
-<li><code>out*</code> {Object, default: {inline:1}} sets the output target for the map reduce job.</li>
-</ul>
-
-<h4>* out options:</h4>
-
-<ul>
-<li><code>{inline:1}</code> the results are returned in an array</li>
-<li><code>{replace: 'collectionName'}</code> add the results to collectionName: the results replace the collection</li>
-<li><code>{reduce: 'collectionName'}</code> add the results to collectionName: if dups are detected, uses the reducer / finalize functions</li>
-<li><code>{merge: 'collectionName'}</code> add the results to collectionName: if dups exist the new docs overwrite the old</li>
-</ul>
-
-<p>If <code>options.out</code> is set to <code>replace</code>, <code>merge</code>, or <code>reduce</code>, a Model instance is returned that can be used for further querying. Queries run against this model are all executed with the <a href="/docs/tutorials/lean.html"><code>lean</code> option</a>; meaning only the js object is returned and no Mongoose magic is applied (getters, setters, etc).</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> o = {};
-<span class="hljs-comment">// You can also define `map()` and `reduce()` as strings if your</span>
-<span class="hljs-comment">// linter complains about `emit()` not being defined</span>
-o.map = <span class="hljs-string">'function () { emit(this.name, 1) }'</span>;
-o.reduce = <span class="hljs-string">'function (k, vals) { return vals.length }'</span>;
-o.out = { replace: <span class="hljs-string">'createdCollectionNameForResults'</span> }
-o.verbose = <span class="hljs-literal">true</span>;
-
-User.mapReduce(o, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, model, stats</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'map reduce took %d ms'</span>, stats.processtime)
-  model.find().where(<span class="hljs-string">'value'</span>).gt(<span class="hljs-number">10</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(docs);
-  });
-})
-
-<span class="hljs-comment">// `mapReduce()` returns a promise. However, ES6 promises can only</span>
-<span class="hljs-comment">// resolve to exactly one value,</span>
-o.resolveToObject = <span class="hljs-literal">true</span>;
-<span class="hljs-keyword">var</span> promise = User.mapReduce(o);
-promise.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">res</span>) </span>{
-  <span class="hljs-keyword">var</span> model = res.model;
-  <span class="hljs-keyword">var</span> stats = res.stats;
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'map reduce took %d ms'</span>, stats.processtime)
-  <span class="hljs-keyword">return</span> model.find().where(<span class="hljs-string">'value'</span>).gt(<span class="hljs-number">10</span>).exec();
-}).then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">docs</span>) </span>{
-   <span class="hljs-built_in">console</span>.log(docs);
-}).then(<span class="hljs-literal">null</span>, handleError).end()</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.populate"><a href="#model_Model.populate">Model.populate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">docs
-<span class="method-type">&laquo;Document|Array&raquo;</span> Either a single document or array of documents to populate.</li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> A hash of key/val (path, options) used for population.</li><ul style="margin-top: 0.5em"><li>[options.retainNullValues=false]
-<span class="method-type">&laquo;boolean&raquo;</span> by default, Mongoose removes null and undefined values from populated arrays. Use this option to make <code>populate()</code> retain <code>null</code> and <code>undefined</code> array entries.</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if true, Mongoose will call any getters defined on the <code>localField</code>. By default, Mongoose gets the raw value of <code>localField</code>. For example, you would need to set this option to <code>true</code> if you wanted to <a href="/docs/schematypes.html#schematype-options">add a <code>lowercase</code> getter to your <code>localField</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.clone=false]
-<span class="method-type">&laquo;boolean&raquo;</span> When you do <code>BlogPost.find().populate(&#39;author&#39;)</code>, blog posts with the same author will share 1 copy of an <code>author</code> doc. Enable this option to make Mongoose clone populated docs before assigning them.</li></ul><ul style="margin-top: 0.5em"><li>[options.match=null]
-<span class="method-type">&laquo;Object|Function&raquo;</span> Add an additional filter to the populate query. Can be a filter object containing <a href="https://docs.mongodb.com/manual/tutorial/query-documents/">MongoDB query syntax</a>, or a function that returns a filter object.</li></ul><ul style="margin-top: 0.5em"><li>[options.skipInvalidIds=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> By default, Mongoose throws a cast error if <code>localField</code> and <code>foreignField</code> schemas don&#39;t line up. If you enable this option, Mongoose will instead filter out any <code>localField</code> properties that cannot be casted to <code>foreignField</code>&#39;s schema type.</li></ul><li class="param">[callback(err,doc)]
-<span class="method-type">&laquo;Function&raquo;</span> Optional callback, executed upon completion. Receives <code>err</code> and the <code>doc(s)</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Populates document references.</p>
-
-<h4>Available top-level options:</h4>
-
-<ul>
-<li>path: space delimited path(s) to populate</li>
-<li>select: optional fields to select</li>
-<li>match: optional query conditions to match</li>
-<li>model: optional name of the model to use for population</li>
-<li>options: optional query options like sort, limit, etc</li>
-<li>justOne: optional boolean, if true Mongoose will always set <code>path</code> to an array. Inferred from schema by default.</li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// populates a single object</span>
-User.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-  <span class="hljs-keyword">var</span> opts = [
-    { path: <span class="hljs-string">'company'</span>, match: { x: <span class="hljs-number">1</span> }, select: <span class="hljs-string">'name'</span> },
-    { path: <span class="hljs-string">'notes'</span>, options: { limit: <span class="hljs-number">10</span> }, model: <span class="hljs-string">'override'</span> }
-  ];
-
-  User.populate(user, opts, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(user);
-  });
-});
-
-<span class="hljs-comment">// populates an array of objects</span>
-User.find(match, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, users</span>) </span>{
-  <span class="hljs-keyword">var</span> opts = [{ path: <span class="hljs-string">'company'</span>, match: { x: <span class="hljs-number">1</span> }, select: <span class="hljs-string">'name'</span> }];
-
-  <span class="hljs-keyword">var</span> promise = User.populate(users, opts);
-  promise.then(<span class="hljs-built_in">console</span>.log).end();
-})
-
-<span class="hljs-comment">// imagine a Weapon model exists with two saved documents:</span>
-<span class="hljs-comment">//   { _id: 389, name: 'whip' }</span>
-<span class="hljs-comment">//   { _id: 8921, name: 'boomerang' }</span>
-<span class="hljs-comment">// and this schema:</span>
-<span class="hljs-comment">// new Schema({</span>
-<span class="hljs-comment">//   name: String,</span>
-<span class="hljs-comment">//   weapon: { type: ObjectId, ref: 'Weapon' }</span>
-<span class="hljs-comment">// });</span>
-
-<span class="hljs-keyword">var</span> user = { name: <span class="hljs-string">'Indiana Jones'</span>, weapon: <span class="hljs-number">389</span> };
-Weapon.populate(user, { path: <span class="hljs-string">'weapon'</span>, model: <span class="hljs-string">'Weapon'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, user</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(user.weapon.name); <span class="hljs-comment">// whip</span>
-})
-
-<span class="hljs-comment">// populate many plain objects</span>
-<span class="hljs-keyword">var</span> users = [{ name: <span class="hljs-string">'Indiana Jones'</span>, weapon: <span class="hljs-number">389</span> }]
-users.push({ name: <span class="hljs-string">'Batman'</span>, weapon: <span class="hljs-number">8921</span> })
-Weapon.populate(users, { path: <span class="hljs-string">'weapon'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, users</span>) </span>{
-  users.forEach(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">user</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s uses a %s'</span>, users.name, user.weapon.name)
-    <span class="hljs-comment">// Indiana Jones uses a whip</span>
-    <span class="hljs-comment">// Batman uses a boomerang</span>
-  });
-});
-<span class="hljs-comment">// Note that we didn't need to specify the Weapon model because</span>
-<span class="hljs-comment">// it is in the schema's ref</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-$where"><a href="#model_Model-$where">Model.prototype.$where</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Additional properties to attach to the query when calling <code>save()</code> and <code>isNew</code> is false.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-$where"><a href="#model_Model-$where">Model.prototype.$where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">argument
-<span class="method-type">&laquo;String|Function&raquo;</span> is a javascript string or anonymous function</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Creates a <code>Query</code> and specifies a <code>$where</code> condition.</p>
-
-<p>Sometimes you need to query for things in mongodb using a JavaScript expression. You can do so via <code>find({ $where: javascript })</code>, or you can use the mongoose shortcut method $where via a Query chain or from your mongoose Model.</p>
-
-<pre><code>Blog.$where(<span class="hljs-string">'this.username.indexOf("val") !== -1'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{});</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-base"><a href="#model_Model-base">Model.prototype.base</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Base Mongoose instance the model uses.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-baseModelName"><a href="#model_Model-baseModelName">Model.prototype.baseModelName</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>If this is a discriminator model, <code>baseModelName</code> is the name of the base model.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-collection"><a href="#model_Model-collection">Model.prototype.collection</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Collection the model uses.</p>
-
-<p>This property is read-only. Modifying this property is a no-op.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-db"><a href="#model_Model-db">Model.prototype.db</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Connection the model uses.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-delete"><a href="#model_Model-delete">Model.prototype.delete</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Alias for remove</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-deleteOne"><a href="#model_Model-deleteOne">Model.prototype.deleteOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[fn]
-<span class="method-type">&laquo;function(err|product)&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> Promise</li></ul><div><p>Removes this document from the db. Equivalent to <code>.remove()</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product = <span class="hljs-keyword">await</span> product.deleteOne();
-<span class="hljs-keyword">await</span> Product.findById(product._id); <span class="hljs-comment">// null</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-discriminators"><a href="#model_Model-discriminators">Model.prototype.discriminators</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Registered discriminators for this model.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-increment"><a href="#model_Model-increment">Model.prototype.increment()</a></h3><div><p>Signal that we desire an increment of this documents version.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Model.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  doc.increment();
-  doc.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{ .. })
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-model"><a href="#model_Model-model">Model.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> model name</li></ul><div><p>Returns another Model instance.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> doc = <span class="hljs-keyword">new</span> Tank;
-doc.model(<span class="hljs-string">'User'</span>).findById(id, callback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-modelName"><a href="#model_Model-modelName">Model.prototype.modelName</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The name of the model</p>  </div><hr class="separate-api-elements"><h3 id="model_Model-remove"><a href="#model_Model-remove">Model.prototype.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[fn]
-<span class="method-type">&laquo;function(err|product)&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> Promise</li></ul><div><p>Removes this document from the db.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.remove(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  Product.findById(product._id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, product</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(product) <span class="hljs-comment">// null</span>
-  })
-})</code></pre>
-
-<p>As an extra measure of flow control, remove will return a Promise (bound to <code>fn</code> if passed) so it could be chained, or hooked to recieve errors</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.remove().then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">product</span>) </span>{
-   ...
-}).catch(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-   assert.ok(err)
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-save"><a href="#model_Model-save">Model.prototype.save()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> options optional options</li><ul style="margin-top: 0.5em"><li>[options.session=null]
-<span class="method-type">&laquo;Session&raquo;</span> the <a href="https://docs.mongodb.com/manual/reference/server-sessions/">session</a> associated with this save operation. If not specified, defaults to the <a href="api.html#document_Document-$session">document&#39;s associated session</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.safe]
-<span class="method-type">&laquo;Object&raquo;</span> (DEPRECATED) overrides <a href="http://mongoosejs.com//docs/guide.html#safe">schema&#39;s safe option</a>. Use the <code>w</code> option instead.</li></ul><ul style="margin-top: 0.5em"><li>[options.validateBeforeSave]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to save without validating.</li></ul><ul style="margin-top: 0.5em"><li>[options.w]
-<span class="method-type">&laquo;Number|String&raquo;</span> set the <a href="https://docs.mongodb.com/manual/reference/write-concern/#w-option">write concern</a>. Overrides the <a href="/docs/guide.html#writeConcern">schema-level <code>writeConcern</code> option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.j]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to true for MongoDB to wait until this <code>save()</code> has been <a href="https://docs.mongodb.com/manual/reference/write-concern/#j-option">journaled before resolving the returned promise</a>. Overrides the <a href="/docs/guide.html#writeConcern">schema-level <code>writeConcern</code> option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.wtimeout]
-<span class="method-type">&laquo;Number&raquo;</span> sets a <a href="https://docs.mongodb.com/manual/reference/write-concern/#wtimeout">timeout for the write concern</a>. Overrides the <a href="/docs/guide.html#writeConcern">schema-level <code>writeConcern</code> option</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.checkKeys=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> the MongoDB driver prevents you from saving keys that start with &#39;$&#39; or contain &#39;.&#39; by default. Set this option to <code>false</code> to skip that check. See <a href="https://docs.mongodb.com/manual/reference/limits/#Restrictions-on-Field-Names">restrictions on field names</a></li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> if <code>false</code> and <a href="./guide.html#timestamps">timestamps</a> are enabled, skip timestamps for this <code>save()</code>.</li></ul><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns undefined if used with callback or a Promise otherwise.</li></ul><div><p>Saves this document.</p>
-
-<h4>Example:</h4>
-
-<pre><code>product.sold = <span class="hljs-built_in">Date</span>.now();
-product = <span class="hljs-keyword">await</span> product.save();</code></pre>
-
-<p>If save is successful, the returned promise will fulfill with the document saved.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> newProduct = <span class="hljs-keyword">await</span> product.save();
-newProduct === product; <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model-schema"><a href="#model_Model-schema">Model.prototype.schema</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Schema the model uses.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.remove"><a href="#model_Model.remove">Model.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">conditions
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Removes all documents that match <code>conditions</code> from the collection. To remove just the first document that matches <code>conditions</code>, set the <code>single</code> option to true.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.remove({ name: <span class="hljs-string">'Eddard Stark'</span> });
-res.deletedCount; <span class="hljs-comment">// Number of documents removed</span></code></pre>
-
-<h4>Note:</h4>
-
-<p>This method sends a remove command directly to MongoDB, no Mongoose documents are involved. Because no Mongoose documents are involved, Mongoose does not execute <a href="/docs/middleware.html#types-of-middleware">document middleware</a>.</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.replaceOne"><a href="#model_Model.replaceOne">Model.replaceOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> <code>function(error, res) {}</code> where <code>res</code> has 3 properties: <code>n</code>, <code>nModified</code>, <code>ok</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Same as <code>update()</code>, except MongoDB replace the existing document with the given document (no atomic operators like <code>$set</code>).</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.replaceOne({ _id: <span class="hljs-number">24601</span> }, { name: <span class="hljs-string">'Jean Valjean'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>replaceOne()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.startSession"><a href="#model_Model.startSession">Model.startSession()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#startSession">mongodb driver options</a></li><ul style="margin-top: 0.5em"><li>[options.causalConsistency=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to disable causal consistency</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&lt;ClientSession&gt;&raquo;</span> promise that resolves to a MongoDB driver <code>ClientSession</code></li></ul><div><p><em>Requires MongoDB >= 3.6.0.</em> Starts a <a href="https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions">MongoDB session</a> for benefits like causal consistency, <a href="https://docs.mongodb.com/manual/core/retryable-writes/">retryable writes</a>, and <a href="http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html">transactions</a>.</p>
-
-<p>Calling <code>MyModel.startSession()</code> is equivalent to calling <code>MyModel.db.startSession()</code>.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> session = <span class="hljs-keyword">await</span> Person.startSession();
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session });
-<span class="hljs-keyword">await</span> doc.remove();
-<span class="hljs-comment">// `doc` will always be null, even if reading from a replica set</span>
-<span class="hljs-comment">// secondary. Without causal consistency, it is possible to</span>
-<span class="hljs-comment">// get a doc back from the below query if the query reads from a</span>
-<span class="hljs-comment">// secondary that is experiencing replication lag.</span>
-doc = <span class="hljs-keyword">await</span> Person.findOne({ name: <span class="hljs-string">'Ned Stark'</span> }, <span class="hljs-literal">null</span>, { session, readPreference: <span class="hljs-string">'secondary'</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.syncIndexes"><a href="#model_Model.syncIndexes">Model.syncIndexes()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> options to pass to <code>ensureIndexes()</code></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional callback</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise,undefined&raquo;</span> Returns <code>undefined</code> if callback is specified, returns a promise if no callback.</li></ul><div><p>Makes the indexes in MongoDB match the indexes defined in this model's schema. This function will drop any indexes that are not defined in the model's schema except the <code>_id</code> index, and build any indexes that are in your schema but not in MongoDB.</p>
-
-<p>See the <a href="http://thecodebarbarian.com/whats-new-in-mongoose-5-2-syncindexes">introductory blog post</a> for more information.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, unique: <span class="hljs-literal">true</span> } });
-<span class="hljs-keyword">const</span> Customer = mongoose.model(<span class="hljs-string">'Customer'</span>, schema);
-<span class="hljs-keyword">await</span> Customer.createIndex({ age: <span class="hljs-number">1</span> }); <span class="hljs-comment">// Index is not in schema</span>
-<span class="hljs-comment">// Will drop the 'age' index and create an index on `name`</span>
-<span class="hljs-keyword">await</span> Customer.syncIndexes();</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.translateAliases"><a href="#model_Model.translateAliases">Model.translateAliases()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">raw
-<span class="method-type">&laquo;Object&raquo;</span> fields/conditions that may contain aliased keys</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the translated &#39;pure&#39; fields/conditions</li></ul><div><p>Translate any aliases fields/conditions so the final query or document object is pure</p>
-
-<h4>Example:</h4>
-
-<pre><code>Character
-  .find(Character.translateAliases({
-    <span class="hljs-string">'名'</span>: <span class="hljs-string">'Eddard Stark'</span> <span class="hljs-comment">// Alias for 'name'</span>
-  })
-  .exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, characters</span>) </span>{})</code></pre>
-
-<h4>Note:</h4>
-
-<p>Only translate arguments of object type anything else is returned raw</p>  </div><hr class="separate-api-elements"><h3 id="model_Model.update"><a href="#model_Model.update">Model.update()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.multi=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> whether multiple documents should be updated or just the first one that matches <code>filter</code>.</li></ul><ul style="margin-top: 0.5em"><li>[options.runValidators=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model&#39;s schema.</li></ul><ul style="margin-top: 0.5em"><li>[options.setDefaultsOnInsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model&#39;s schema if a new document is created. This option only works on MongoDB &gt;= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB&#39;s <code>$setOnInsert</code> operator</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><ul style="margin-top: 0.5em"><li>[options.overwrite=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> By default, if you don&#39;t include any <a href="https://docs.mongodb.com/manual/reference/operator/update/">update operators</a> in <code>doc</code>, Mongoose will wrap <code>doc</code> in <code>$set</code> for you. This prevents you from accidentally overwriting the document. This option tells Mongoose to skip adding <code>$set</code>.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Updates one document in the database without returning it.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>update()</code></li>
-</ul>
-
-<h4>Examples:</h4>
-
-<pre><code>MyModel.update({ age: { $gt: <span class="hljs-number">18</span> } }, { oldEnough: <span class="hljs-literal">true</span> }, fn);
-
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> MyModel.update({ name: <span class="hljs-string">'Tobi'</span> }, { ferret: <span class="hljs-literal">true</span> });
-res.n; <span class="hljs-comment">// Number of documents that matched `{ name: 'Tobi' }`</span>
-<span class="hljs-comment">// Number of documents that were changed. If every doc matched already</span>
-<span class="hljs-comment">// had `ferret` set to `true`, `nModified` will be 0.</span>
-res.nModified;</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li><code>strict</code> (boolean): overrides the <a href="/docs/guide.html#strict">schema-level <code>strict</code> option</a> for this update</li>
-<li><code>upsert</code> (boolean): whether to create the doc if it doesn't match (false)</li>
-<li><code>writeConcern</code> (object): sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li>
-<li><code>omitUndefined</code> (boolean): If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: 'bar', baz: undefined })</code> before sending the update to the server.</li>
-<li><code>multi</code> (boolean): whether multiple documents should be updated (false)</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code> (boolean): if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>timestamps</code> (boolean): If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li>
-<li><code>overwrite</code> (boolean): disables update-only mode, allowing you to overwrite the doc (false)</li>
-</ul>
-
-<p>All <code>update</code> values are cast to their appropriate SchemaTypes before being sent.</p>
-
-<p>The <code>callback</code> function receives <code>(err, rawResponse)</code>.</p>
-
-<ul>
-<li><code>err</code> is the error if any occurred</li>
-<li><code>rawResponse</code> is the full response from Mongo</li>
-</ul>
-
-<h4>Note:</h4>
-
-<p>All top level keys which are not <code>atomic</code> operation names are treated as set operations:</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = { name: <span class="hljs-string">'borne'</span> };
-Model.update(query, { name: <span class="hljs-string">'jason bourne'</span> }, options, callback);
-
-<span class="hljs-comment">// is sent as</span>
-Model.update(query, { $set: { name: <span class="hljs-string">'jason bourne'</span> }}, options, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, res</span>));
-// <span class="hljs-title">if</span> <span class="hljs-title">overwrite</span> <span class="hljs-title">option</span> <span class="hljs-title">is</span> <span class="hljs-title">false</span>. <span class="hljs-title">If</span> <span class="hljs-title">overwrite</span> <span class="hljs-title">is</span> <span class="hljs-title">true</span>, <span class="hljs-title">sent</span> <span class="hljs-title">without</span> <span class="hljs-title">the</span> <span class="hljs-title">$set</span> <span class="hljs-title">wrapper</span>.
-</span></code></pre>
-
-<p>This helps prevent accidentally overwriting all documents in your collection with <code>{ name: 'jason bourne' }</code>.</p>
-
-<h4>Note:</h4>
-
-<p>Be careful to not use an existing model instance for the update clause (this won't work and can cause weird behavior like infinite loops). Also, ensure that the update clause does not have an _id property, which causes Mongo to return a "Mod on _id not allowed" error.</p>
-
-<h4>Note:</h4>
-
-<p>Mongoose casts values and runs setters when using update. The following features are <strong>not</strong> applied by default.</p>
-
-<ul>
-<li><a href="/docs/defaults.html#the-setdefaultsoninsert-option">defaults</a></li>
-<li><a href="/docs/validation.html#update-validators">validators</a></li>
-<li>middleware</li>
-</ul>
-
-<p>If you need document middleware and fully-featured validation, load the document first and then use <a href="/docs/api.html#model_Model-save"><code>save()</code></a>.</p>
-
-<pre><code>Model.findOne({ name: <span class="hljs-string">'borne'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) ..
-  doc.name = <span class="hljs-string">'jason bourne'</span>;
-  doc.save(callback);
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.updateMany"><a href="#model_Model.updateMany">Model.updateMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> <code>function(error, res) {}</code> where <code>res</code> has 3 properties: <code>n</code>, <code>nModified</code>, <code>ok</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Same as <code>update()</code>, except MongoDB will update <em>all</em> documents that match <code>filter</code> (as opposed to just the first one) regardless of the value of the <code>multi</code> option.</p>
-
-<p><strong>Note</strong> updateMany will <em>not</em> fire update middleware. Use <code>pre('updateMany')</code> and <code>post('updateMany')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateMany({ name: <span class="hljs-regexp">/Stark$/</span> }, { isDeleted: <span class="hljs-literal">true</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateMany()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.updateOne"><a href="#model_Model.updateOne">Model.updateOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">filter
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> optional see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>Query.prototype.setOptions()</code></a></li><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Same as <code>update()</code>, except it does not support the <code>multi</code> or <code>overwrite</code> options.</p>
-
-<ul>
-<li>MongoDB will update <em>only</em> the first document that matches <code>filter</code> regardless of the value of the <code>multi</code> option.</li>
-<li>Use <code>replaceOne()</code> if you want to overwrite an entire document rather than using atomic operators like <code>$set</code>.</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateOne({ name: <span class="hljs-string">'Jean-Luc Picard'</span> }, { ship: <span class="hljs-string">'USS Enterprise'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateOne()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="model_Model.watch"><a href="#model_Model.watch">Model.watch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[pipeline]
-<span class="method-type">&laquo;Array&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/Collection.html#watch">mongodb driver options</a></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;ChangeStream&raquo;</span> mongoose-specific change stream wrapper, inherits from EventEmitter</li></ul><div><p><em>Requires a replica set running MongoDB >= 3.6.0.</em> Watches the underlying collection for changes using <a href="https://docs.mongodb.com/manual/changeStreams/">MongoDB change streams</a>.</p>
-
-<p>This function does <strong>not</strong> trigger any middleware. In particular, it does <strong>not</strong> trigger aggregate middleware.</p>
-
-<h2>The ChangeStream object is an event emitter that emits the following events</h2>
-
-<ul>
-<li>'change': A change occurred, see below example</li>
-<li>'error': An unrecoverable error occurred. In particular, change streams currently error out if they lose connection to the replica set primary. Follow <a href="https://github.com/Automattic/mongoose/issues/6799">this GitHub issue</a> for updates.</li>
-<li>'end': Emitted if the underlying stream is closed</li>
-<li>'close': Emitted if the underlying stream is closed</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Person.create({ name: <span class="hljs-string">'Ned Stark'</span> });
-<span class="hljs-keyword">const</span> changeStream = Person.watch().on(<span class="hljs-string">'change'</span>, change =&gt; <span class="hljs-built_in">console</span>.log(change));
-<span class="hljs-comment">// Will print from the above `console.log()`:</span>
-<span class="hljs-comment">// { _id: { _data: ... },</span>
-<span class="hljs-comment">//   operationType: 'delete',</span>
-<span class="hljs-comment">//   ns: { db: 'mydb', coll: 'Person' },</span>
-<span class="hljs-comment">//   documentKey: { _id: 5a51b125c5500f5aa094c7bd } }</span>
-<span class="hljs-keyword">await</span> doc.remove();</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.where"><a href="#model_Model.where">Model.where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[val]
-<span class="method-type">&laquo;Object&raquo;</span> optional value</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> </li></ul><div><p>Creates a Query, applies the passed conditions, and returns the Query.</p>
-
-<p>For example, instead of writing:</p>
-
-<pre><code>User.find({age: {$gte: <span class="hljs-number">21</span>, $lte: <span class="hljs-number">65</span>}}, callback);</code></pre>
-
-<p>we can instead write:</p>
-
-<pre><code>User.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>).exec(callback);</code></pre>
-
-<p>Since the Query class also supports <code>where</code> you can continue chaining</p>
-
-<pre><code>User
-.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>)
-.where(<span class="hljs-string">'name'</span>, <span class="hljs-regexp">/^b/i</span>)
-... etc</code></pre>  </div><hr class="separate-api-elements"><h3 id="model_Model.inspect"><a href="#model_Model.inspect">function Object() { [native code] }.prototype.inspect()</a></h3><div><p>Helper for console.log</p>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/mongoose.html b/docs/api/mongoose.html
deleted file mode 100644
index f48284709bf..00000000000
--- a/docs/api/mongoose.html
+++ /dev/null
@@ -1,317 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Mongoose</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title" style="font-weight: bold"><a href="mongoose.html">Mongoose</a></div><ul class="nav-item-sub"><li><a href="#mongoose_Mongoose">Mongoose()</a></li><li><a href="#mongoose_Mongoose-Aggregate">Mongoose.prototype.Aggregate()</a></li><li><a href="#mongoose_Mongoose-CastError">Mongoose.prototype.CastError()</a></li><li><a href="#mongoose_Mongoose-Collection">Mongoose.prototype.Collection()</a></li><li><a href="#mongoose_Mongoose-Connection">Mongoose.prototype.Connection()</a></li><li><a href="#mongoose_Mongoose-Decimal128">Mongoose.prototype.Decimal128</a></li><li><a href="#mongoose_Mongoose-Document">Mongoose.prototype.Document()</a></li><li><a href="#mongoose_Mongoose-DocumentProvider">Mongoose.prototype.DocumentProvider()</a></li><li><a href="#mongoose_Mongoose-Error">Mongoose.prototype.Error()</a></li><li><a href="#mongoose_Mongoose-Mixed">Mongoose.prototype.Mixed</a></li><li><a href="#mongoose_Mongoose-Model">Mongoose.prototype.Model()</a></li><li><a href="#mongoose_Mongoose-Mongoose">Mongoose.prototype.Mongoose()</a></li><li><a href="#mongoose_Mongoose-Number">Mongoose.prototype.Number</a></li><li><a href="#mongoose_Mongoose-ObjectId">Mongoose.prototype.ObjectId</a></li><li><a href="#mongoose_Mongoose-Promise">Mongoose.prototype.Promise</a></li><li><a href="#mongoose_Mongoose-PromiseProvider">Mongoose.prototype.PromiseProvider()</a></li><li><a href="#mongoose_Mongoose-Query">Mongoose.prototype.Query()</a></li><li><a href="#mongoose_Mongoose-STATES">Mongoose.prototype.STATES</a></li><li><a href="#mongoose_Mongoose-Schema">Mongoose.prototype.Schema()</a></li><li><a href="#mongoose_Mongoose-SchemaType">Mongoose.prototype.SchemaType()</a></li><li><a href="#mongoose_Mongoose-SchemaTypes">Mongoose.prototype.SchemaTypes</a></li><li><a href="#mongoose_Mongoose-Types">Mongoose.prototype.Types</a></li><li><a href="#mongoose_Mongoose-VirtualType">Mongoose.prototype.VirtualType()</a></li><li><a href="#mongoose_Mongoose-connect">Mongoose.prototype.connect()</a></li><li><a href="#mongoose_Mongoose-connection">Mongoose.prototype.connection</a></li><li><a href="#mongoose_Mongoose-connections">Mongoose.prototype.connections</a></li><li><a href="#mongoose_Mongoose-createConnection">Mongoose.prototype.createConnection()</a></li><li><a href="#mongoose_Mongoose-deleteModel">Mongoose.prototype.deleteModel()</a></li><li><a href="#mongoose_Mongoose-disconnect">Mongoose.prototype.disconnect()</a></li><li><a href="#mongoose_Mongoose-driver">Mongoose.prototype.driver</a></li><li><a href="#mongoose_Mongoose-get">Mongoose.prototype.get()</a></li><li><a href="#mongoose_Mongoose-model">Mongoose.prototype.model()</a></li><li><a href="#mongoose_Mongoose-modelNames">Mongoose.prototype.modelNames()</a></li><li><a href="#mongoose_Mongoose-mongo">Mongoose.prototype.mongo</a></li><li><a href="#mongoose_Mongoose-mquery">Mongoose.prototype.mquery</a></li><li><a href="#mongoose_Mongoose-now">Mongoose.prototype.now()</a></li><li><a href="#mongoose_Mongoose-plugin">Mongoose.prototype.plugin()</a></li><li><a href="#mongoose_Mongoose-pluralize">Mongoose.prototype.pluralize()</a></li><li><a href="#mongoose_Mongoose-set">Mongoose.prototype.set()</a></li><li><a href="#mongoose_Mongoose-startSession">Mongoose.prototype.startSession()</a></li><li><a href="#mongoose_Mongoose-version">Mongoose.prototype.version</a></li></ul></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#mongoose_Mongoose">Mongoose()</a></li><li><a href="#mongoose_Mongoose-Aggregate">Mongoose.prototype.Aggregate()</a></li><li><a href="#mongoose_Mongoose-CastError">Mongoose.prototype.CastError()</a></li><li><a href="#mongoose_Mongoose-Collection">Mongoose.prototype.Collection()</a></li><li><a href="#mongoose_Mongoose-Connection">Mongoose.prototype.Connection()</a></li><li><a href="#mongoose_Mongoose-Decimal128">Mongoose.prototype.Decimal128</a></li><li><a href="#mongoose_Mongoose-Document">Mongoose.prototype.Document()</a></li><li><a href="#mongoose_Mongoose-DocumentProvider">Mongoose.prototype.DocumentProvider()</a></li><li><a href="#mongoose_Mongoose-Error">Mongoose.prototype.Error()</a></li><li><a href="#mongoose_Mongoose-Mixed">Mongoose.prototype.Mixed</a></li><li><a href="#mongoose_Mongoose-Model">Mongoose.prototype.Model()</a></li><li><a href="#mongoose_Mongoose-Mongoose">Mongoose.prototype.Mongoose()</a></li><li><a href="#mongoose_Mongoose-Number">Mongoose.prototype.Number</a></li><li><a href="#mongoose_Mongoose-ObjectId">Mongoose.prototype.ObjectId</a></li><li><a href="#mongoose_Mongoose-Promise">Mongoose.prototype.Promise</a></li><li><a href="#mongoose_Mongoose-PromiseProvider">Mongoose.prototype.PromiseProvider()</a></li><li><a href="#mongoose_Mongoose-Query">Mongoose.prototype.Query()</a></li><li><a href="#mongoose_Mongoose-STATES">Mongoose.prototype.STATES</a></li><li><a href="#mongoose_Mongoose-Schema">Mongoose.prototype.Schema()</a></li><li><a href="#mongoose_Mongoose-SchemaType">Mongoose.prototype.SchemaType()</a></li><li><a href="#mongoose_Mongoose-SchemaTypes">Mongoose.prototype.SchemaTypes</a></li><li><a href="#mongoose_Mongoose-Types">Mongoose.prototype.Types</a></li><li><a href="#mongoose_Mongoose-VirtualType">Mongoose.prototype.VirtualType()</a></li><li><a href="#mongoose_Mongoose-connect">Mongoose.prototype.connect()</a></li><li><a href="#mongoose_Mongoose-connection">Mongoose.prototype.connection</a></li><li><a href="#mongoose_Mongoose-connections">Mongoose.prototype.connections</a></li><li><a href="#mongoose_Mongoose-createConnection">Mongoose.prototype.createConnection()</a></li><li><a href="#mongoose_Mongoose-deleteModel">Mongoose.prototype.deleteModel()</a></li><li><a href="#mongoose_Mongoose-disconnect">Mongoose.prototype.disconnect()</a></li><li><a href="#mongoose_Mongoose-driver">Mongoose.prototype.driver</a></li><li><a href="#mongoose_Mongoose-get">Mongoose.prototype.get()</a></li><li><a href="#mongoose_Mongoose-model">Mongoose.prototype.model()</a></li><li><a href="#mongoose_Mongoose-modelNames">Mongoose.prototype.modelNames()</a></li><li><a href="#mongoose_Mongoose-mongo">Mongoose.prototype.mongo</a></li><li><a href="#mongoose_Mongoose-mquery">Mongoose.prototype.mquery</a></li><li><a href="#mongoose_Mongoose-now">Mongoose.prototype.now()</a></li><li><a href="#mongoose_Mongoose-plugin">Mongoose.prototype.plugin()</a></li><li><a href="#mongoose_Mongoose-pluralize">Mongoose.prototype.pluralize()</a></li><li><a href="#mongoose_Mongoose-set">Mongoose.prototype.set()</a></li><li><a href="#mongoose_Mongoose-startSession">Mongoose.prototype.startSession()</a></li><li><a href="#mongoose_Mongoose-version">Mongoose.prototype.version</a></li></ul><hr class="separate-api-elements"><h3 id="mongoose_Mongoose"><a href="#mongoose_Mongoose">Mongoose()</a></h3><div><p>Mongoose constructor.</p>
-
-<p>The exports object of the <code>mongoose</code> module is an instance of this class. Most apps will only use this one instance.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Aggregate"><a href="#mongoose_Mongoose-Aggregate">Mongoose.prototype.Aggregate()</a></h3><div><p>The Mongoose Aggregate constructor</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-CastError"><a href="#mongoose_Mongoose-CastError">Mongoose.prototype.CastError()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">type
-<span class="method-type">&laquo;String&raquo;</span> The name of the type</li><li class="param">value
-<span class="method-type">&laquo;Any&raquo;</span> The value that failed to cast</li><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> The path <code>a.b.c</code> in the doc where this cast error occurred</li><li class="param">[reason]
-<span class="method-type">&laquo;Error&raquo;</span> The original error that was thrown</li></ul><div><p>The Mongoose CastError constructor</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Collection"><a href="#mongoose_Mongoose-Collection">Mongoose.prototype.Collection()</a></h3><div><p>The Mongoose Collection constructor</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Connection"><a href="#mongoose_Mongoose-Connection">Mongoose.prototype.Connection()</a></h3><div><p>The Mongoose <a href="#connection_Connection">Connection</a> constructor</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Decimal128"><a href="#mongoose_Mongoose-Decimal128">Mongoose.prototype.Decimal128</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose Decimal128 <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that should be <a href="http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-decimal.html">128-bit decimal floating points</a>. Do not use this to create a new Decimal128 instance, use <code>mongoose.Types.Decimal128</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> vehicleSchema = <span class="hljs-keyword">new</span> Schema({ fuelLevel: mongoose.Decimal128 });</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Document"><a href="#mongoose_Mongoose-Document">Mongoose.prototype.Document()</a></h3><div><p>The Mongoose <a href="#document-js">Document</a> constructor.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-DocumentProvider"><a href="#mongoose_Mongoose-DocumentProvider">Mongoose.prototype.DocumentProvider()</a></h3><div><p>The Mongoose DocumentProvider constructor. Mongoose users should not have to use this directly</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Error"><a href="#mongoose_Mongoose-Error">Mongoose.prototype.Error()</a></h3><div><p>The <a href="#error_MongooseError">MongooseError</a> constructor.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Mixed"><a href="#mongoose_Mongoose-Mixed">Mongoose.prototype.Mixed</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose Mixed <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that Mongoose's change tracking, casting, and validation should ignore.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ arbitrary: mongoose.Mixed });</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Model"><a href="#mongoose_Mongoose-Model">Mongoose.prototype.Model()</a></h3><div><p>The Mongoose <a href="#model_Model">Model</a> constructor.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Mongoose"><a href="#mongoose_Mongoose-Mongoose">Mongoose.prototype.Mongoose()</a></h3><div><p>The Mongoose constructor</p>
-
-<p>The exports of the mongoose module is an instance of this class.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> mongoose2 = <span class="hljs-keyword">new</span> mongoose.Mongoose();</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Number"><a href="#mongoose_Mongoose-Number">Mongoose.prototype.Number</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose Number <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that Mongoose should cast to numbers.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ num: mongoose.Number });
-<span class="hljs-comment">// Equivalent to:</span>
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ num: <span class="hljs-string">'number'</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-ObjectId"><a href="#mongoose_Mongoose-ObjectId">Mongoose.prototype.ObjectId</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose ObjectId <a href="/docs/schematypes.html">SchemaType</a>. Used for declaring paths in your schema that should be <a href="https://docs.mongodb.com/manual/reference/method/ObjectId/">MongoDB ObjectIds</a>. Do not use this to create a new ObjectId instance, use <code>mongoose.Types.ObjectId</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> childSchema = <span class="hljs-keyword">new</span> Schema({ parentId: mongoose.ObjectId });</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Promise"><a href="#mongoose_Mongoose-Promise">Mongoose.prototype.Promise</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose <a href="#promise_Promise">Promise</a> constructor.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-PromiseProvider"><a href="#mongoose_Mongoose-PromiseProvider">Mongoose.prototype.PromiseProvider()</a></h3><div><p>Storage layer for mongoose promises</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Query"><a href="#mongoose_Mongoose-Query">Mongoose.prototype.Query()</a></h3><div><p>The Mongoose <a href="#query_Query">Query</a> constructor.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-STATES"><a href="#mongoose_Mongoose-STATES">Mongoose.prototype.STATES</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Expose connection states for user-land</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Schema"><a href="#mongoose_Mongoose-Schema">Mongoose.prototype.Schema()</a></h3><div><p>The Mongoose <a href="#schema_Schema">Schema</a> constructor</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> Schema = mongoose.Schema;
-<span class="hljs-keyword">var</span> CatSchema = <span class="hljs-keyword">new</span> Schema(..);</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-SchemaType"><a href="#mongoose_Mongoose-SchemaType">Mongoose.prototype.SchemaType()</a></h3><div><p>The Mongoose <a href="#schematype_SchemaType">SchemaType</a> constructor</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-SchemaTypes"><a href="#mongoose_Mongoose-SchemaTypes">Mongoose.prototype.SchemaTypes</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The various Mongoose SchemaTypes.</p>
-
-<h4>Note:</h4>
-
-<p><em>Alias of mongoose.Schema.Types for backwards compatibility.</em></p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-Types"><a href="#mongoose_Mongoose-Types">Mongoose.prototype.Types</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The various Mongoose Types.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> array = mongoose.Types.Array;</code></pre>
-
-<h4>Types:</h4>
-
-<ul>
-<li><a href="#types-objectid-js">ObjectId</a></li>
-<li><a href="#types-buffer-js">Buffer</a></li>
-<li><a href="#types-embedded-js">SubDocument</a></li>
-<li><a href="#types-array-js">Array</a></li>
-<li><a href="#types-documentarray-js">DocumentArray</a></li>
-</ul>
-
-<p>Using this exposed access to the <code>ObjectId</code> type, we can construct ids on demand.</p>
-
-<pre><code><span class="hljs-keyword">var</span> ObjectId = mongoose.Types.ObjectId;
-<span class="hljs-keyword">var</span> id1 = <span class="hljs-keyword">new</span> ObjectId;</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-VirtualType"><a href="#mongoose_Mongoose-VirtualType">Mongoose.prototype.VirtualType()</a></h3><div><p>The Mongoose <a href="#virtualtype_VirtualType">VirtualType</a> constructor</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-connect"><a href="#mongoose_Mongoose-connect">Mongoose.prototype.connect()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">uri(s)
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> passed down to the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html">MongoDB driver&#39;s <code>connect()</code> function</a>, except for 4 mongoose-specific options explained below.</li><ul style="margin-top: 0.5em"><li>[options.dbName]
-<span class="method-type">&laquo;String&raquo;</span> The name of the database we want to use. If not provided, use database name from connection string.</li></ul><ul style="margin-top: 0.5em"><li>[options.user]
-<span class="method-type">&laquo;String&raquo;</span> username for authentication, equivalent to <code>options.auth.user</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.pass]
-<span class="method-type">&laquo;String&raquo;</span> password for authentication, equivalent to <code>options.auth.password</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.autoIndex=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.</li></ul><ul style="margin-top: 0.5em"><li>[options.bufferCommands=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose specific option. Set to false to <a href="http://mongoosejs.com/docs/faq.html#callback_never_executes">disable buffering</a> on all models associated with this connection.</li></ul><ul style="margin-top: 0.5em"><li>[options.useCreateIndex=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose-specific option. If <code>true</code>, this connection will use <a href="/docs/deprecations.html#-ensureindex-"><code>createIndex()</code> instead of <code>ensureIndex()</code></a> for automatic index builds via <a href="/docs/api.html#model_Model.init"><code>Model.init()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.useFindAndModify=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> True by default. Set to <code>false</code> to make <code>findOneAndUpdate()</code> and <code>findOneAndRemove()</code> use native <code>findOneAndUpdate()</code> rather than <code>findAndModify()</code>.</li></ul><ul style="margin-top: 0.5em"><li>[options.useNewUrlParser=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> False by default. Set to <code>true</code> to make all connections set the <code>useNewUrlParser</code> option by default.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> resolves to <code>this</code> if connection succeeded</li></ul><div><p>Opens the default mongoose connection.</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.connect(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>);
-
-<span class="hljs-comment">// replica sets</span>
-<span class="hljs-keyword">var</span> uri = <span class="hljs-string">'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/mydatabase'</span>;
-mongoose.connect(uri);
-
-<span class="hljs-comment">// with options</span>
-mongoose.connect(uri, options);
-
-<span class="hljs-comment">// optional callback that gets fired when initial connection completed</span>
-<span class="hljs-keyword">var</span> uri = <span class="hljs-string">'mongodb://nonexistent.domain:27000'</span>;
-mongoose.connect(uri, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// if error is truthy, the initial connection failed.</span>
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-connection"><a href="#mongoose_Mongoose-connection">Mongoose.prototype.connection</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span></li></ul><div><p>The Mongoose module's default connection. Equivalent to <code>mongoose.connections][0]</code>, see <a href="#mongoose_Mongoose-connections"><code>connections</code></a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.connect(...);
-mongoose.connection.on(<span class="hljs-string">'error'</span>, cb);</code></pre>
-
-<p>This is the connection used by default for every model created using <a href="#index_Mongoose-model">mongoose.model</a>.</p>
-
-<p>To create a new connection, use <a href="#mongoose_Mongoose-createConnection"><code>createConnection()</code></a>.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-connections"><a href="#mongoose_Mongoose-connections">Mongoose.prototype.connections</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span></li></ul><div><p>An array containing all <a href="connections.html">connections</a> associated with this Mongoose instance. By default, there is 1 connection. Calling <a href="#mongoose_Mongoose-createConnection"><code>createConnection()</code></a> adds a connection to this array.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.connections.length; <span class="hljs-comment">// 1, just the default connection</span>
-mongoose.connections[<span class="hljs-number">0</span>] === mongoose.connection; <span class="hljs-comment">// true</span>
-
-mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/test'</span>);
-mongoose.connections.length; <span class="hljs-comment">// 2</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-createConnection"><a href="#mongoose_Mongoose-createConnection">Mongoose.prototype.createConnection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[uri]
-<span class="method-type">&laquo;String&raquo;</span> a mongodb:// URI</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> passed down to the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html">MongoDB driver&#39;s <code>connect()</code> function</a>, except for 4 mongoose-specific options explained below.</li><ul style="margin-top: 0.5em"><li>[options.user]
-<span class="method-type">&laquo;String&raquo;</span> username for authentication, equivalent to <code>options.auth.user</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.pass]
-<span class="method-type">&laquo;String&raquo;</span> password for authentication, equivalent to <code>options.auth.password</code>. Maintained for backwards compatibility.</li></ul><ul style="margin-top: 0.5em"><li>[options.autoIndex=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose-specific option. Set to false to disable automatic index creation for all models associated with this connection.</li></ul><ul style="margin-top: 0.5em"><li>[options.bufferCommands=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> Mongoose specific option. Set to false to <a href="http://mongoosejs.com/docs/faq.html#callback_never_executes">disable buffering</a> on all models associated with this connection.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Connection&raquo;</span> the created Connection object. Connections are thenable, so you can do <code>await mongoose.createConnection()</code></li></ul><div><p>Creates a Connection instance.</p>
-
-<p>Each <code>connection</code> instance maps to a single database. This method is helpful when mangaging multiple db connections.</p>
-
-<p><em>Options passed take precedence over options included in connection strings.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// with mongodb:// URI</span>
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>);
-
-<span class="hljs-comment">// and options</span>
-<span class="hljs-keyword">var</span> opts = { db: { native_parser: <span class="hljs-literal">true</span> }}
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>, opts);
-
-<span class="hljs-comment">// replica sets</span>
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/database'</span>);
-
-<span class="hljs-comment">// and options</span>
-<span class="hljs-keyword">var</span> opts = { replset: { strategy: <span class="hljs-string">'ping'</span>, rs_name: <span class="hljs-string">'testSet'</span> }}
-db = mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port,anotherhost:port,yetanother:port/database'</span>, opts);
-
-<span class="hljs-comment">// and options</span>
-<span class="hljs-keyword">var</span> opts = { server: { auto_reconnect: <span class="hljs-literal">false</span> }, user: <span class="hljs-string">'username'</span>, pass: <span class="hljs-string">'mypassword'</span> }
-db = mongoose.createConnection(<span class="hljs-string">'localhost'</span>, <span class="hljs-string">'database'</span>, port, opts)
-
-<span class="hljs-comment">// initialize now, connect later</span>
-db = mongoose.createConnection();
-db.openUri(<span class="hljs-string">'localhost'</span>, <span class="hljs-string">'database'</span>, port, [opts]);</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-deleteModel"><a href="#mongoose_Mongoose-deleteModel">Mongoose.prototype.deleteModel()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|RegExp&raquo;</span> if string, the name of the model to remove. If regexp, removes all models whose name matches the regexp.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Mongoose&raquo;</span> this</li></ul><div><p>Removes the model named <code>name</code> from the default connection, if it exists. You can use this function to clean up any models you created in your tests to prevent OverwriteModelErrors.</p>
-
-<p>Equivalent to <code>mongoose.connection.deleteModel(name)</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-built_in">console</span>.log(mongoose.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// Model object</span>
-mongoose.deleteModel(<span class="hljs-string">'User'</span>);
-<span class="hljs-built_in">console</span>.log(mongoose.model(<span class="hljs-string">'User'</span>)); <span class="hljs-comment">// undefined</span>
-
-<span class="hljs-comment">// Usually useful in a Mocha `afterEach()` hook</span>
-afterEach(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  mongoose.deleteModel(<span class="hljs-regexp">/.+/</span>); <span class="hljs-comment">// Delete every model</span>
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-disconnect"><a href="#mongoose_Mongoose-disconnect">Mongoose.prototype.disconnect()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> called after all connection close, or when first error occurred.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> resolves when all connections are closed, or rejects with the first error that occurred.</li></ul><div><p>Runs <code>.close()</code> on all connections in parallel.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-driver"><a href="#mongoose_Mongoose-driver">Mongoose.prototype.driver</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The underlying driver this Mongoose instance uses to communicate with the database. A driver is a Mongoose-specific interface that defines functions like <code>find()</code>.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-get"><a href="#mongoose_Mongoose-get">Mongoose.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Gets mongoose options</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.get(<span class="hljs-string">'test'</span>) <span class="hljs-comment">// returns the 'test' value</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-model"><a href="#mongoose_Mongoose-model">Mongoose.prototype.model()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|Function&raquo;</span> model name or class extending Model</li><li class="param">[schema]
-<span class="method-type">&laquo;Schema&raquo;</span> the schema to use.</li><li class="param">[collection]
-<span class="method-type">&laquo;String&raquo;</span> name (optional, inferred from model name)</li><li class="param">[skipInit]
-<span class="method-type">&laquo;Boolean&raquo;</span> whether to skip initialization (defaults to false)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Model&raquo;</span> The model associated with <code>name</code>. Mongoose will create the model if it doesn&#39;t already exist.</li></ul><div><p>Defines a model or retrieves it.</p>
-
-<p>Models defined on the <code>mongoose</code> instance are available to all connection created by the same <code>mongoose</code> instance.</p>
-
-<p>If you call <code>mongoose.model()</code> with twice the same name but a different schema, you will get an <code>OverwriteModelError</code>. If you call <code>mongoose.model()</code> with the same name and same schema, you'll get the same schema back.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-
-<span class="hljs-comment">// define an Actor model with this mongoose instance</span>
-<span class="hljs-keyword">const</span> Schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-mongoose.model(<span class="hljs-string">'Actor'</span>, schema);
-
-<span class="hljs-comment">// create a new connection</span>
-<span class="hljs-keyword">var</span> conn = mongoose.createConnection(..);
-
-<span class="hljs-comment">// create Actor model</span>
-<span class="hljs-keyword">var</span> Actor = conn.model(<span class="hljs-string">'Actor'</span>, schema);
-conn.model(<span class="hljs-string">'Actor'</span>) === Actor; <span class="hljs-comment">// true</span>
-conn.model(<span class="hljs-string">'Actor'</span>, schema) === Actor; <span class="hljs-comment">// true, same schema</span>
-conn.model(<span class="hljs-string">'Actor'</span>, schema, <span class="hljs-string">'actors'</span>) === Actor; <span class="hljs-comment">// true, same schema and collection name</span>
-
-<span class="hljs-comment">// This throws an `OverwriteModelError` because the schema is different.</span>
-conn.model(<span class="hljs-string">'Actor'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));</code></pre>
-
-<p><em>When no <code>collection</code> argument is passed, Mongoose uses the model name. If you don't like this behavior, either pass a collection name, use <code>mongoose.pluralize()</code>, or set your schemas collection name option.</em></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { collection: <span class="hljs-string">'actor'</span> });
-
-<span class="hljs-comment">// or</span>
-
-schema.set(<span class="hljs-string">'collection'</span>, <span class="hljs-string">'actor'</span>);
-
-<span class="hljs-comment">// or</span>
-
-<span class="hljs-keyword">var</span> collectionName = <span class="hljs-string">'actor'</span>
-<span class="hljs-keyword">var</span> M = mongoose.model(<span class="hljs-string">'Actor'</span>, schema, collectionName)</code></pre>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-modelNames"><a href="#mongoose_Mongoose-modelNames">Mongoose.prototype.modelNames()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns an array of model names created on this instance of Mongoose.</p>
-
-<h4>Note:</h4>
-
-<p><em>Does not include names of models created using <code>connection.model()</code>.</em></p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-mongo"><a href="#mongoose_Mongoose-mongo">Mongoose.prototype.mongo</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The <a href="https://github.com/mongodb/node-mongodb-native">node-mongodb-native</a> driver Mongoose uses.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-mquery"><a href="#mongoose_Mongoose-mquery">Mongoose.prototype.mquery</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The <a href="https://github.com/aheckmann/mquery">mquery</a> query builder Mongoose uses.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-now"><a href="#mongoose_Mongoose-now">Mongoose.prototype.now()</a></h3><div><p>Mongoose uses this function to get the current time when setting <a href="/docs/guide.html#timestamps">timestamps</a>. You may stub out this function using a tool like <a href="https://www.npmjs.com/package/sinon">Sinon</a> for testing.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-plugin"><a href="#mongoose_Mongoose-plugin">Mongoose.prototype.plugin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> plugin callback</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> optional options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Mongoose&raquo;</span> this</li></ul><div><p>Declares a global plugin executed on all Schemas.</p>
-
-<p>Equivalent to calling <code>.plugin(fn)</code> on each Schema you create.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-pluralize"><a href="#mongoose_Mongoose-pluralize">Mongoose.prototype.pluralize()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[fn]
-<span class="method-type">&laquo;Function|null&raquo;</span> overwrites the function used to pluralize collection names</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Function,null&raquo;</span> the current function used to pluralize collection names, defaults to the legacy function from <code>mongoose-legacy-pluralize</code>.</li></ul><div><p>Getter/setter around function for pluralizing collection names.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-set"><a href="#mongoose_Mongoose-set">Mongoose.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;String|Function|Boolean&raquo;</span> </li></ul><div><p>Sets mongoose options</p>
-
-<h4>Example:</h4>
-
-<pre><code>mongoose.set(<span class="hljs-string">'test'</span>, value) <span class="hljs-comment">// sets the 'test' option to `value`</span>
-
-mongoose.set(<span class="hljs-string">'debug'</span>, <span class="hljs-literal">true</span>) <span class="hljs-comment">// enable logging collection methods + arguments to the console</span>
-
-mongoose.set(<span class="hljs-string">'debug'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">collectionName, methodName, arg1, arg2...</span>) </span>{}); <span class="hljs-comment">// use custom function to log collection methods + arguments</span></code></pre>
-
-<h2>Currently supported options are</h2>
-
-<ul>
-<li>'debug': prints the operations mongoose sends to MongoDB to the console</li>
-<li>'bufferCommands': enable/disable mongoose's buffering mechanism for all connections and models</li>
-<li>'useCreateIndex': false by default. Set to <code>true</code> to make Mongoose's default index build use <code>createIndex()</code> instead of <code>ensureIndex()</code> to avoid deprecation warnings from the MongoDB driver.</li>
-<li>'useFindAndModify': true by default. Set to <code>false</code> to make <code>findOneAndUpdate()</code> and <code>findOneAndRemove()</code> use native <code>findOneAndUpdate()</code> rather than <code>findAndModify()</code>.</li>
-<li>'useNewUrlParser': false by default. Set to <code>true</code> to make all connections set the <code>useNewUrlParser</code> option by default</li>
-<li>'cloneSchemas': false by default. Set to <code>true</code> to <code>clone()</code> all schemas before compiling into a model.</li>
-<li>'applyPluginsToDiscriminators': false by default. Set to true to apply global plugins to discriminator schemas. This typically isn't necessary because plugins are applied to the base schema and discriminators copy all middleware, methods, statics, and properties from the base schema.</li>
-<li>'objectIdGetter': true by default. Mongoose adds a getter to MongoDB ObjectId's called <code>_id</code> that returns <code>this</code> for convenience with populate. Set this to false to remove the getter.</li>
-<li>'runValidators': false by default. Set to true to enable <a href="/docs/validation.html#update-validators">update validators</a> for all validators by default.</li>
-<li>'toObject': <code>{ transform: true, flattenDecimals: true }</code> by default. Overwrites default objects to <a href="/docs/api.html#document_Document-toObject"><code>toObject()</code></a></li>
-<li>'toJSON': <code>{ transform: true, flattenDecimals: true }</code> by default. Overwrites default objects to <a href="/docs/api.html#document_Document-toJSON"><code>toJSON()</code></a>, for determining how Mongoose documents get serialized by <code>JSON.stringify()</code></li>
-<li>'strict': true by default, may be <code>false</code>, <code>true</code>, or <code>'throw'</code>. Sets the default strict mode for schemas.</li>
-<li>'selectPopulatedPaths': true by default. Set to false to opt out of Mongoose adding all fields that you <code>populate()</code> to your <code>select()</code>. The schema-level option <code>selectPopulatedPaths</code> overwrites this one.</li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-startSession"><a href="#mongoose_Mongoose-startSession">Mongoose.prototype.startSession()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see the <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#startSession">mongodb driver options</a></li><ul style="margin-top: 0.5em"><li>[options.causalConsistency=true]
-<span class="method-type">&laquo;Boolean&raquo;</span> set to false to disable causal consistency</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&lt;ClientSession&gt;&raquo;</span> promise that resolves to a MongoDB driver <code>ClientSession</code></li></ul><div><p><em>Requires MongoDB >= 3.6.0.</em> Starts a <a href="https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions">MongoDB session</a> for benefits like causal consistency, <a href="https://docs.mongodb.com/manual/core/retryable-writes/">retryable writes</a>, and <a href="http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html">transactions</a>.</p>
-
-<p>Calling <code>mongoose.startSession()</code> is equivalent to calling <code>mongoose.connection.startSession()</code>. Sessions are scoped to a connection, so calling <code>mongoose.startSession()</code> starts a session on the <a href="/docs/api.html#mongoose_Mongoose-connection">default mongoose connection</a>.</p>  </div><hr class="separate-api-elements"><h3 id="mongoose_Mongoose-version"><a href="#mongoose_Mongoose-version">Mongoose.prototype.version</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The Mongoose version</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-built_in">console</span>.log(mongoose.version); <span class="hljs-comment">// '5.x.x'</span></code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/mongooseerror.html b/docs/api/mongooseerror.html
deleted file mode 100644
index 6f31d704ec6..00000000000
--- a/docs/api/mongooseerror.html
+++ /dev/null
@@ -1,84 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>MongooseError</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-MongooseError"><div class="nav-item-title" style="font-weight: bold"><a href="mongooseerror.html">MongooseError</a></div><ul class="nav-item-sub"><li><a href="#mongooseerror_MongooseError">MongooseError()</a></li><li><a href="#mongooseerror_MongooseError-name">MongooseError.prototype.name</a></li></ul></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#mongooseerror_MongooseError">MongooseError()</a></li><li><a href="#mongooseerror_MongooseError-name">MongooseError.prototype.name</a></li></ul><hr class="separate-api-elements"><h3 id="mongooseerror_MongooseError"><a href="#mongooseerror_MongooseError">MongooseError()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">msg
-<span class="method-type">&laquo;String&raquo;</span> Error message</li></ul><div><p>MongooseError constructor. MongooseError is the base class for all Mongoose-specific errors.</p>  </div><hr class="separate-api-elements"><h3 id="mongooseerror_MongooseError-name"><a href="#mongooseerror_MongooseError-name">MongooseError.prototype.name</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;String&raquo;</span></li></ul><div><p>The name of the error. The name uniquely identifies this Mongoose error. The possible values are:</p>
-
-<ul>
-<li><code>MongooseError</code>: general Mongoose error</li>
-<li><code>CastError</code>: Mongoose could not convert a value to the type defined in the schema path. May be in a <code>ValidationError</code> class' <code>errors</code> property.</li>
-<li><code>DisconnectedError</code>: This <a href="connections.html">connection</a> timed out in trying to reconnect to MongoDB and will not successfully reconnect to MongoDB unless you explicitly reconnect.</li>
-<li><code>DivergentArrayError</code>: You attempted to <code>save()</code> an array that was modified after you loaded it with a <code>$elemMatch</code> or similar projection</li>
-<li><code>MissingSchemaError</code>: You tried to access a model with <a href="api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> that was not defined</li>
-<li><code>DocumentNotFoundError</code>: The document you tried to <a href="api.html#document_Document-save"><code>save()</code></a> was not found</li>
-<li><code>ValidatorError</code>: error from an individual schema path's validator</li>
-<li><code>ValidationError</code>: error returned from <a href="api.html#document_Document-validate"><code>validate()</code></a> or <a href="api.html#document_Document-validateSync"><code>validateSync()</code></a>. Contains zero or more <code>ValidatorError</code> instances in <code>.errors</code> property.</li>
-<li><code>MissingSchemaError</code>: You called <code>mongoose.Document()</code> without a schema</li>
-<li><code>ObjectExpectedError</code>: Thrown when you set a nested path to a non-object value with <a href="guide.html#strict">strict mode set</a>.</li>
-<li><code>ObjectParameterError</code>: Thrown when you pass a non-object value to a function which expects an object as a paramter</li>
-<li><code>OverwriteModelError</code>: Thrown when you call <a href="api.html#mongoose_Mongoose-model"><code>mongoose.model()</code></a> to re-define a model that was already defined.</li>
-<li><code>ParallelSaveError</code>: Thrown when you call <a href="api.html#model_Model-save"><code>save()</code></a> on a document when the same document instance is already saving.</li>
-<li><code>StrictModeError</code>: Thrown when you set a path that isn't the schema and <a href="guide.html#strict">strict mode</a> is set to <code>throw</code>.</li>
-<li><code>VersionError</code>: Thrown when the <a href="guide.html#versionKey">document is out of sync</a></li>
-</ul>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/query.html b/docs/api/query.html
deleted file mode 100644
index 00338894dff..00000000000
--- a/docs/api/query.html
+++ /dev/null
@@ -1,1600 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Query</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title" style="font-weight: bold"><a href="query.html">Query</a></div><ul class="nav-item-sub"><li><a href="#query_Query">Query()</a></li><li><a href="#query_Query-$where">Query.prototype.$where()</a></li><li><a href="#query_Query-Symbol.asyncIterator">Query.prototype.Symbol.asyncIterator()</a></li><li><a href="#query_Query-all">Query.prototype.all()</a></li><li><a href="#query_Query-and">Query.prototype.and()</a></li><li><a href="#query_Query-batchSize">Query.prototype.batchSize()</a></li><li><a href="#query_Query-box">Query.prototype.box()</a></li><li><a href="#query_Query-cast">Query.prototype.cast()</a></li><li><a href="#query_Query-catch">Query.prototype.catch()</a></li><li><a href="#query_Query-center">Query.prototype.center()</a></li><li><a href="#query_Query-centerSphere">Query.prototype.centerSphere()</a></li><li><a href="#query_Query-circle">Query.prototype.circle()</a></li><li><a href="#query_Query-collation">Query.prototype.collation()</a></li><li><a href="#query_Query-comment">Query.prototype.comment()</a></li><li><a href="#query_Query-count">Query.prototype.count()</a></li><li><a href="#query_Query-countDocuments">Query.prototype.countDocuments()</a></li><li><a href="#query_Query-cursor">Query.prototype.cursor()</a></li><li><a href="#query_Query-deleteMany">Query.prototype.deleteMany()</a></li><li><a href="#query_Query-deleteOne">Query.prototype.deleteOne()</a></li><li><a href="#query_Query-distinct">Query.prototype.distinct()</a></li><li><a href="#query_Query-elemMatch">Query.prototype.elemMatch()</a></li><li><a href="#query_Query-equals">Query.prototype.equals()</a></li><li><a href="#query_Query-error">Query.prototype.error()</a></li><li><a href="#query_Query-estimatedDocumentCount">Query.prototype.estimatedDocumentCount()</a></li><li><a href="#query_Query-exec">Query.prototype.exec()</a></li><li><a href="#query_Query-exists">Query.prototype.exists()</a></li><li><a href="#query_Query-explain">Query.prototype.explain()</a></li><li><a href="#query_Query-find">Query.prototype.find()</a></li><li><a href="#query_Query-findOne">Query.prototype.findOne()</a></li><li><a href="#query_Query-findOneAndDelete">Query.prototype.findOneAndDelete()</a></li><li><a href="#query_Query-findOneAndRemove">Query.prototype.findOneAndRemove()</a></li><li><a href="#query_Query-findOneAndReplace">Query.prototype.findOneAndReplace()</a></li><li><a href="#query_Query-findOneAndUpdate">Query.prototype.findOneAndUpdate()</a></li><li><a href="#query_Query-geometry">Query.prototype.geometry()</a></li><li><a href="#query_Query-getFilter">Query.prototype.getFilter()</a></li><li><a href="#query_Query-getOptions">Query.prototype.getOptions()</a></li><li><a href="#query_Query-getPopulatedPaths">Query.prototype.getPopulatedPaths()</a></li><li><a href="#query_Query-getQuery">Query.prototype.getQuery()</a></li><li><a href="#query_Query-getUpdate">Query.prototype.getUpdate()</a></li><li><a href="#query_Query-gt">Query.prototype.gt()</a></li><li><a href="#query_Query-gte">Query.prototype.gte()</a></li><li><a href="#query_Query-hint">Query.prototype.hint()</a></li><li><a href="#query_Query-in">Query.prototype.in()</a></li><li><a href="#query_Query-intersects">Query.prototype.intersects()</a></li><li><a href="#query_Query-j">Query.prototype.j()</a></li><li><a href="#query_Query-lean">Query.prototype.lean()</a></li><li><a href="#query_Query-limit">Query.prototype.limit()</a></li><li><a href="#query_Query-lt">Query.prototype.lt()</a></li><li><a href="#query_Query-lte">Query.prototype.lte()</a></li><li><a href="#query_Query-map">Query.prototype.map()</a></li><li><a href="#query_Query-maxDistance">Query.prototype.maxDistance()</a></li><li><a href="#query_Query-maxScan">Query.prototype.maxScan()</a></li><li><a href="#query_Query-maxTimeMS">Query.prototype.maxTimeMS()</a></li><li><a href="#query_Query-maxscan">Query.prototype.maxscan()</a></li><li><a href="#query_Query-merge">Query.prototype.merge()</a></li><li><a href="#query_Query-mod">Query.prototype.mod()</a></li><li><a href="#query_Query-mongooseOptions">Query.prototype.mongooseOptions()</a></li><li><a href="#query_Query-ne">Query.prototype.ne()</a></li><li><a href="#query_Query-near">Query.prototype.near()</a></li><li><a href="#query_Query-nearSphere">Query.prototype.nearSphere()</a></li><li><a href="#query_Query-nin">Query.prototype.nin()</a></li><li><a href="#query_Query-nor">Query.prototype.nor()</a></li><li><a href="#query_Query-or">Query.prototype.or()</a></li><li><a href="#query_Query-orFail">Query.prototype.orFail()</a></li><li><a href="#query_Query-polygon">Query.prototype.polygon()</a></li><li><a href="#query_Query-populate">Query.prototype.populate()</a></li><li><a href="#query_Query-projection">Query.prototype.projection()</a></li><li><a href="#query_Query-read">Query.prototype.read()</a></li><li><a href="#query_Query-readConcern">Query.prototype.readConcern()</a></li><li><a href="#query_Query-regex">Query.prototype.regex()</a></li><li><a href="#query_Query-remove">Query.prototype.remove()</a></li><li><a href="#query_Query-replaceOne">Query.prototype.replaceOne()</a></li><li><a href="#query_Query-select">Query.prototype.select()</a></li><li><a href="#query_Query-selected">Query.prototype.selected()</a></li><li><a href="#query_Query-selectedExclusively">Query.prototype.selectedExclusively()</a></li><li><a href="#query_Query-selectedInclusively">Query.prototype.selectedInclusively()</a></li><li><a href="#query_Query-session">Query.prototype.session()</a></li><li><a href="#query_Query-set">Query.prototype.set()</a></li><li><a href="#query_Query-setOptions">Query.prototype.setOptions()</a></li><li><a href="#query_Query-setQuery">Query.prototype.setQuery()</a></li><li><a href="#query_Query-setUpdate">Query.prototype.setUpdate()</a></li><li><a href="#query_Query-size">Query.prototype.size()</a></li><li><a href="#query_Query-skip">Query.prototype.skip()</a></li><li><a href="#query_Query-slaveOk">Query.prototype.slaveOk()</a></li><li><a href="#query_Query-slice">Query.prototype.slice()</a></li><li><a href="#query_Query-snapshot">Query.prototype.snapshot()</a></li><li><a href="#query_Query-sort">Query.prototype.sort()</a></li><li><a href="#query_Query-tailable">Query.prototype.tailable()</a></li><li><a href="#query_Query-then">Query.prototype.then()</a></li><li><a href="#query_Query-toConstructor">Query.prototype.toConstructor()</a></li><li><a href="#query_Query-update">Query.prototype.update()</a></li><li><a href="#query_Query-updateMany">Query.prototype.updateMany()</a></li><li><a href="#query_Query-updateOne">Query.prototype.updateOne()</a></li><li><a href="#query_Query-use$geoWithin">Query.prototype.use$geoWithin</a></li><li><a href="#query_Query-w">Query.prototype.w()</a></li><li><a href="#query_Query-where">Query.prototype.where()</a></li><li><a href="#query_Query-within">Query.prototype.within()</a></li><li><a href="#query_Query-wtimeout">Query.prototype.wtimeout()</a></li></ul></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#query_Query">Query()</a></li><li><a href="#query_Query-$where">Query.prototype.$where()</a></li><li><a href="#query_Query-Symbol.asyncIterator">Query.prototype.Symbol.asyncIterator()</a></li><li><a href="#query_Query-all">Query.prototype.all()</a></li><li><a href="#query_Query-and">Query.prototype.and()</a></li><li><a href="#query_Query-batchSize">Query.prototype.batchSize()</a></li><li><a href="#query_Query-box">Query.prototype.box()</a></li><li><a href="#query_Query-cast">Query.prototype.cast()</a></li><li><a href="#query_Query-catch">Query.prototype.catch()</a></li><li><a href="#query_Query-center">Query.prototype.center()</a></li><li><a href="#query_Query-centerSphere">Query.prototype.centerSphere()</a></li><li><a href="#query_Query-circle">Query.prototype.circle()</a></li><li><a href="#query_Query-collation">Query.prototype.collation()</a></li><li><a href="#query_Query-comment">Query.prototype.comment()</a></li><li><a href="#query_Query-count">Query.prototype.count()</a></li><li><a href="#query_Query-countDocuments">Query.prototype.countDocuments()</a></li><li><a href="#query_Query-cursor">Query.prototype.cursor()</a></li><li><a href="#query_Query-deleteMany">Query.prototype.deleteMany()</a></li><li><a href="#query_Query-deleteOne">Query.prototype.deleteOne()</a></li><li><a href="#query_Query-distinct">Query.prototype.distinct()</a></li><li><a href="#query_Query-elemMatch">Query.prototype.elemMatch()</a></li><li><a href="#query_Query-equals">Query.prototype.equals()</a></li><li><a href="#query_Query-error">Query.prototype.error()</a></li><li><a href="#query_Query-estimatedDocumentCount">Query.prototype.estimatedDocumentCount()</a></li><li><a href="#query_Query-exec">Query.prototype.exec()</a></li><li><a href="#query_Query-exists">Query.prototype.exists()</a></li><li><a href="#query_Query-explain">Query.prototype.explain()</a></li><li><a href="#query_Query-find">Query.prototype.find()</a></li><li><a href="#query_Query-findOne">Query.prototype.findOne()</a></li><li><a href="#query_Query-findOneAndDelete">Query.prototype.findOneAndDelete()</a></li><li><a href="#query_Query-findOneAndRemove">Query.prototype.findOneAndRemove()</a></li><li><a href="#query_Query-findOneAndReplace">Query.prototype.findOneAndReplace()</a></li><li><a href="#query_Query-findOneAndUpdate">Query.prototype.findOneAndUpdate()</a></li><li><a href="#query_Query-geometry">Query.prototype.geometry()</a></li><li><a href="#query_Query-getFilter">Query.prototype.getFilter()</a></li><li><a href="#query_Query-getOptions">Query.prototype.getOptions()</a></li><li><a href="#query_Query-getPopulatedPaths">Query.prototype.getPopulatedPaths()</a></li><li><a href="#query_Query-getQuery">Query.prototype.getQuery()</a></li><li><a href="#query_Query-getUpdate">Query.prototype.getUpdate()</a></li><li><a href="#query_Query-gt">Query.prototype.gt()</a></li><li><a href="#query_Query-gte">Query.prototype.gte()</a></li><li><a href="#query_Query-hint">Query.prototype.hint()</a></li><li><a href="#query_Query-in">Query.prototype.in()</a></li><li><a href="#query_Query-intersects">Query.prototype.intersects()</a></li><li><a href="#query_Query-j">Query.prototype.j()</a></li><li><a href="#query_Query-lean">Query.prototype.lean()</a></li><li><a href="#query_Query-limit">Query.prototype.limit()</a></li><li><a href="#query_Query-lt">Query.prototype.lt()</a></li><li><a href="#query_Query-lte">Query.prototype.lte()</a></li><li><a href="#query_Query-map">Query.prototype.map()</a></li><li><a href="#query_Query-maxDistance">Query.prototype.maxDistance()</a></li><li><a href="#query_Query-maxScan">Query.prototype.maxScan()</a></li><li><a href="#query_Query-maxTimeMS">Query.prototype.maxTimeMS()</a></li><li><a href="#query_Query-maxscan">Query.prototype.maxscan()</a></li><li><a href="#query_Query-merge">Query.prototype.merge()</a></li><li><a href="#query_Query-mod">Query.prototype.mod()</a></li><li><a href="#query_Query-mongooseOptions">Query.prototype.mongooseOptions()</a></li><li><a href="#query_Query-ne">Query.prototype.ne()</a></li><li><a href="#query_Query-near">Query.prototype.near()</a></li><li><a href="#query_Query-nearSphere">Query.prototype.nearSphere()</a></li><li><a href="#query_Query-nin">Query.prototype.nin()</a></li><li><a href="#query_Query-nor">Query.prototype.nor()</a></li><li><a href="#query_Query-or">Query.prototype.or()</a></li><li><a href="#query_Query-orFail">Query.prototype.orFail()</a></li><li><a href="#query_Query-polygon">Query.prototype.polygon()</a></li><li><a href="#query_Query-populate">Query.prototype.populate()</a></li><li><a href="#query_Query-projection">Query.prototype.projection()</a></li><li><a href="#query_Query-read">Query.prototype.read()</a></li><li><a href="#query_Query-readConcern">Query.prototype.readConcern()</a></li><li><a href="#query_Query-regex">Query.prototype.regex()</a></li><li><a href="#query_Query-remove">Query.prototype.remove()</a></li><li><a href="#query_Query-replaceOne">Query.prototype.replaceOne()</a></li><li><a href="#query_Query-select">Query.prototype.select()</a></li><li><a href="#query_Query-selected">Query.prototype.selected()</a></li><li><a href="#query_Query-selectedExclusively">Query.prototype.selectedExclusively()</a></li><li><a href="#query_Query-selectedInclusively">Query.prototype.selectedInclusively()</a></li><li><a href="#query_Query-session">Query.prototype.session()</a></li><li><a href="#query_Query-set">Query.prototype.set()</a></li><li><a href="#query_Query-setOptions">Query.prototype.setOptions()</a></li><li><a href="#query_Query-setQuery">Query.prototype.setQuery()</a></li><li><a href="#query_Query-setUpdate">Query.prototype.setUpdate()</a></li><li><a href="#query_Query-size">Query.prototype.size()</a></li><li><a href="#query_Query-skip">Query.prototype.skip()</a></li><li><a href="#query_Query-slaveOk">Query.prototype.slaveOk()</a></li><li><a href="#query_Query-slice">Query.prototype.slice()</a></li><li><a href="#query_Query-snapshot">Query.prototype.snapshot()</a></li><li><a href="#query_Query-sort">Query.prototype.sort()</a></li><li><a href="#query_Query-tailable">Query.prototype.tailable()</a></li><li><a href="#query_Query-then">Query.prototype.then()</a></li><li><a href="#query_Query-toConstructor">Query.prototype.toConstructor()</a></li><li><a href="#query_Query-update">Query.prototype.update()</a></li><li><a href="#query_Query-updateMany">Query.prototype.updateMany()</a></li><li><a href="#query_Query-updateOne">Query.prototype.updateOne()</a></li><li><a href="#query_Query-use$geoWithin">Query.prototype.use$geoWithin</a></li><li><a href="#query_Query-w">Query.prototype.w()</a></li><li><a href="#query_Query-where">Query.prototype.where()</a></li><li><a href="#query_Query-within">Query.prototype.within()</a></li><li><a href="#query_Query-wtimeout">Query.prototype.wtimeout()</a></li></ul><hr class="separate-api-elements"><h3 id="query_Query"><a href="#query_Query">Query()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[model]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[collection]
-<span class="method-type">&laquo;Object&raquo;</span> Mongoose collection</li></ul><div><p>Query constructor used for building queries. You do not need to instantiate a <code>Query</code> directly. Instead use Model functions like <a href="/docs/api.html#find_find"><code>Model.find()</code></a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = MyModel.find(); <span class="hljs-comment">// `query` is an instance of `Query`</span>
-query.setOptions({ lean : <span class="hljs-literal">true</span> });
-query.collection(MyModel.collection);
-query.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).exec(callback);
-
-<span class="hljs-comment">// You can instantiate a query directly. There is no need to do</span>
-<span class="hljs-comment">// this unless you're an advanced user with a very good reason to.</span>
-<span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> mongoose.Query();</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-$where"><a href="#query_Query-$where">Query.prototype.$where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">js
-<span class="method-type">&laquo;String|Function&raquo;</span> javascript string or function</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a javascript function or expression to pass to MongoDBs query system.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.$where(<span class="hljs-string">'this.comments.length === 10 || this.name.length === 5'</span>)
-
-<span class="hljs-comment">// or</span>
-
-query.$where(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.comments.length === <span class="hljs-number">10</span> || <span class="hljs-keyword">this</span>.name.length === <span class="hljs-number">5</span>;
-})</code></pre>
-
-<h4>NOTE:</h4>
-
-<p>Only use <code>$where</code> when you have a condition that cannot be met using other MongoDB operators like <code>$lt</code>. <strong>Be sure to read about all of <a href="http://docs.mongodb.org/manual/reference/operator/where/">its caveats</a> before using.</strong></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-Symbol.asyncIterator"><a href="#query_Query-Symbol.asyncIterator">Query.prototype.Symbol.asyncIterator()</a></h3><div><p>Returns an asyncIterator for use with <a href="http://bit.ly/async-iterators"><code>for/await/of</code> loops</a> This function <em>only</em> works for <code>find()</code> queries. You do not need to call this function explicitly, the JavaScript runtime will call it for you.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">for</span> <span class="hljs-keyword">await</span> (<span class="hljs-keyword">const</span> doc <span class="hljs-keyword">of</span> Model.aggregate([{ $sort: { name: <span class="hljs-number">1</span> } }])) {
-  <span class="hljs-built_in">console</span>.log(doc.name);
-}</code></pre>
-
-<p>Node.js 10.x supports async iterators natively without any flags. You can enable async iterators in Node.js 8.x using the <a href="https://github.com/tc39/proposal-async-iteration/issues/117#issuecomment-346695187"><code>--harmony_async_iteration</code> flag</a>.</p>
-
-<p><strong>Note:</strong> This function is not if <code>Symbol.asyncIterator</code> is undefined. If <code>Symbol.asyncIterator</code> is undefined, that means your Node.js version does not support async iterators.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-all"><a href="#query_Query-all">Query.prototype.all()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Specifies an <code>$all</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>
-
-<h4>Example:</h4>
-
-<pre><code>MyModel.find().where(<span class="hljs-string">'pets'</span>).all([<span class="hljs-string">'dog'</span>, <span class="hljs-string">'cat'</span>, <span class="hljs-string">'ferret'</span>]);
-<span class="hljs-comment">// Equivalent:</span>
-MyModel.find().all(<span class="hljs-string">'pets'</span>, [<span class="hljs-string">'dog'</span>, <span class="hljs-string">'cat'</span>, <span class="hljs-string">'ferret'</span>]);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-and"><a href="#query_Query-and">Query.prototype.and()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">array
-<span class="method-type">&laquo;Array&raquo;</span> array of conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies arguments for a <code>$and</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.and([{ color: <span class="hljs-string">'green'</span> }, { status: <span class="hljs-string">'ok'</span> }])</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-batchSize"><a href="#query_Query-batchSize">Query.prototype.batchSize()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the batchSize option.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.batchSize(<span class="hljs-number">100</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-box"><a href="#query_Query-box">Query.prototype.box()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">Upper
-<span class="method-type">&laquo;[Array]&raquo;</span> Right Coords</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$box</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> lowerLeft = [<span class="hljs-number">40.73083</span>, <span class="hljs-number">-73.99756</span>]
-<span class="hljs-keyword">var</span> upperRight= [<span class="hljs-number">40.741404</span>,  <span class="hljs-number">-73.988135</span>]
-
-query.where(<span class="hljs-string">'loc'</span>).within().box(lowerLeft, upperRight)
-query.box({ ll : lowerLeft, ur : upperRight })</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-cast"><a href="#query_Query-cast">Query.prototype.cast()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[model]
-<span class="method-type">&laquo;Model&raquo;</span> the model to cast to. If not set, defaults to <code>this.model</code></li><li class="param">[obj]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Casts this query to the schema of <code>model</code></p>
-
-<h4>Note</h4>
-
-<p>If <code>obj</code> is present, it is cast instead of this query.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-catch"><a href="#query_Query-catch">Query.prototype.catch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query returning a <code>Promise</code> which will be resolved with either the doc(s) or rejected with the error. Like <code>.then()</code>, but only takes a rejection handler.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-center"><a href="#query_Query-center">Query.prototype.center()</a></h3><div><p><em>DEPRECATED</em> Alias for <a href="#query_Query-circle">circle</a></p>
-
-<p><strong>Deprecated.</strong> Use <a href="#query_Query-circle">circle</a> instead.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-centerSphere"><a href="#query_Query-centerSphere">Query.prototype.centerSphere()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p><em>DEPRECATED</em> Specifies a <code>$centerSphere</code> condition</p>
-
-<p><strong>Deprecated.</strong> Use <a href="#query_Query-circle">circle</a> instead.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> area = { center: [<span class="hljs-number">50</span>, <span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span> };
-query.where(<span class="hljs-string">'loc'</span>).within().centerSphere(area);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-circle"><a href="#query_Query-circle">Query.prototype.circle()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">area
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$center</code> or <code>$centerSphere</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> area = { center: [<span class="hljs-number">50</span>, <span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span>, unique: <span class="hljs-literal">true</span> }
-query.where(<span class="hljs-string">'loc'</span>).within().circle(area)
-<span class="hljs-comment">// alternatively</span>
-query.circle(<span class="hljs-string">'loc'</span>, area);
-
-<span class="hljs-comment">// spherical calculations</span>
-<span class="hljs-keyword">var</span> area = { center: [<span class="hljs-number">50</span>, <span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span>, unique: <span class="hljs-literal">true</span>, spherical: <span class="hljs-literal">true</span> }
-query.where(<span class="hljs-string">'loc'</span>).within().circle(area)
-<span class="hljs-comment">// alternatively</span>
-query.circle(<span class="hljs-string">'loc'</span>, area);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-collation"><a href="#query_Query-collation">Query.prototype.collation()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Adds a collation to this op (MongoDB 3.4 and up)</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-comment"><a href="#query_Query-comment">Query.prototype.comment()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Specifies the <code>comment</code> option.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.comment(<span class="hljs-string">'login query'</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-count"><a href="#query_Query-count">Query.prototype.count()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> count documents that match this object</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, count)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>count</code> query.</p>
-
-<p>This method is deprecated. If you want to count the number of documents in a collection, e.g. <code>count({})</code>, use the <a href="/docs/api.html#query_Query-estimatedDocumentCount"><code>estimatedDocumentCount()</code> function</a> instead. Otherwise, use the <a href="/docs/api.html#query_Query-countDocuments"><code>countDocuments()</code></a> function instead.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>count()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> countQuery = model.where({ <span class="hljs-string">'color'</span>: <span class="hljs-string">'black'</span> }).count();
-
-query.count({ color: <span class="hljs-string">'black'</span> }).count(callback)
-
-query.count({ color: <span class="hljs-string">'black'</span> }, callback)
-
-query.where(<span class="hljs-string">'color'</span>, <span class="hljs-string">'black'</span>).count(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d kittens'</span>, count);
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-countDocuments"><a href="#query_Query-countDocuments">Query.prototype.countDocuments()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, count)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>countDocuments()</code> query. Behaves like <code>count()</code>, except it always does a full collection scan when passed an empty filter <code>{}</code>.</p>
-
-<p>There are also minor differences in how <code>countDocuments()</code> handles <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments"><code>$where</code> and a couple geospatial operators</a>. versus <code>count()</code>.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>countDocuments()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> countQuery = model.where({ <span class="hljs-string">'color'</span>: <span class="hljs-string">'black'</span> }).countDocuments();
-
-query.countDocuments({ color: <span class="hljs-string">'black'</span> }).count(callback);
-
-query.countDocuments({ color: <span class="hljs-string">'black'</span> }, callback);
-
-query.where(<span class="hljs-string">'color'</span>, <span class="hljs-string">'black'</span>).countDocuments(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, count</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'there are %d kittens'</span>, count);
-});</code></pre>
-
-<p>The <code>countDocuments()</code> function is similar to <code>count()</code>, but there are a <a href="https://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#countDocuments">few operators that <code>countDocuments()</code> does not support</a>. Below are the operators that <code>count()</code> supports but <code>countDocuments()</code> does not, and the suggested replacement:</p>
-
-<ul>
-<li><code>$where</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/expr/"><code>$expr</code></a></li>
-<li><code>$near</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/center/#op._S_center"><code>$center</code></a></li>
-<li><code>$nearSphere</code>: <a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/"><code>$geoWithin</code></a> with <a href="https://docs.mongodb.com/manual/reference/operator/query/centerSphere/#op._S_centerSphere"><code>$centerSphere</code></a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="query_Query-cursor"><a href="#query_Query-cursor">Query.prototype.cursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;QueryCursor&raquo;</span> </li></ul><div><p>Returns a wrapper around a <a href="http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html">mongodb driver cursor</a>. A QueryCursor exposes a Streams3 interface, as well as a <code>.next()</code> function.</p>
-
-<p>The <code>.cursor()</code> function triggers pre find hooks, but <strong>not</strong> post find hooks.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// There are 2 ways to use a cursor. First, as a stream:</span>
-Thing.
-  find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{ <span class="hljs-built_in">console</span>.log(doc); }).
-  on(<span class="hljs-string">'end'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Done!'</span>); });
-
-<span class="hljs-comment">// Or you can use `.next()` to manually get the next doc in the stream.</span>
-<span class="hljs-comment">// `.next()` returns a promise, so you can use promises or callbacks.</span>
-<span class="hljs-keyword">var</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).cursor();
-cursor.next(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc);
-});
-
-<span class="hljs-comment">// Because `.next()` returns a promise, you can use co</span>
-<span class="hljs-comment">// to easily iterate through all documents without loading them</span>
-<span class="hljs-comment">// all into memory.</span>
-co(<span class="hljs-function"><span class="hljs-keyword">function</span>*(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">const</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).cursor();
-  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">yield</span> cursor.next(); doc != <span class="hljs-literal">null</span>; doc = <span class="hljs-keyword">yield</span> cursor.next()) {
-    <span class="hljs-built_in">console</span>.log(doc);
-  }
-});</code></pre>
-
-<h4>Valid options</h4>
-
-<ul>
-<li><code>transform</code>: optional function which accepts a mongoose document. The return value of the function will be emitted on <code>data</code> and returned by <code>.next()</code>.</li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="query_Query-deleteMany"><a href="#query_Query-deleteMany">Query.prototype.deleteMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, mongooseDeleteResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a <code>deleteMany()</code> operation. Works like remove, except it deletes <em>every</em> document that matches <code>filter</code> in the collection, regardless of the value of <code>single</code>.</p>
-
-<p>This function does not trigger any middleware</p>
-
-<h4>Example</h4>
-
-<pre><code>Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } }, callback)
-Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } }).then(next)</code></pre>
-
-<p>This function calls the MongoDB driver's <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#deleteMany"><code>Collection#deleteMany()</code> function</a>. The returned <a href="https://mongoosejs.com/docs/queries.html">promise</a> resolves to an object that contains 3 properties:</p>
-
-<ul>
-<li><code>ok</code>: <code>1</code> if no errors occurred</li>
-<li><code>deletedCount</code>: the number of documents deleted</li>
-<li><code>n</code>: the number of documents deleted. Equal to <code>deletedCount</code>.</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.deleteMany({ name: <span class="hljs-regexp">/Stark/</span>, age: { $gte: <span class="hljs-number">18</span> } });
-<span class="hljs-comment">// `0` if no docs matched the filter, number of docs deleted otherwise</span>
-res.deletedCount;</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-deleteOne"><a href="#query_Query-deleteOne">Query.prototype.deleteOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, mongooseDeleteResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a <code>deleteOne()</code> operation. Works like remove, except it deletes at most one document regardless of the <code>single</code> option.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example</h4>
-
-<pre><code>Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> }, callback);
-Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> }).then(next);</code></pre>
-
-<p>This function calls the MongoDB driver's <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#deleteOne"><code>Collection#deleteOne()</code> function</a>. The returned <a href="https://mongoosejs.com/docs/queries.html">promise</a> resolves to an object that contains 3 properties:</p>
-
-<ul>
-<li><code>ok</code>: <code>1</code> if no errors occurred</li>
-<li><code>deletedCount</code>: the number of documents deleted</li>
-<li><code>n</code>: the number of documents deleted. Equal to <code>deletedCount</code>.</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.deleteOne({ name: <span class="hljs-string">'Eddard Stark'</span> });
-<span class="hljs-comment">// `1` if MongoDB deleted a doc, `0` if no docs matched the filter `{ name: ... }`</span>
-res.deletedCount;</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-distinct"><a href="#query_Query-distinct">Query.prototype.distinct()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[field]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, arr)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declares or executes a distinct() operation.</p>
-
-<p>Passing a <code>callback</code> executes the query.</p>
-
-<p>This function does not trigger any middleware.</p>
-
-<h4>Example</h4>
-
-<pre><code>distinct(field, conditions, callback)
-distinct(field, conditions)
-distinct(field, callback)
-distinct(field)
-distinct(callback)
-distinct()</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-elemMatch"><a href="#query_Query-elemMatch">Query.prototype.elemMatch()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object|Function&raquo;</span> </li><li class="param">filter
-<span class="method-type">&laquo;Object|Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies an <code>$elemMatch</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code>query.elemMatch(<span class="hljs-string">'comment'</span>, { author: <span class="hljs-string">'autobot'</span>, votes: {$gte: <span class="hljs-number">5</span>}})
-
-query.where(<span class="hljs-string">'comment'</span>).elemMatch({ author: <span class="hljs-string">'autobot'</span>, votes: {$gte: <span class="hljs-number">5</span>}})
-
-query.elemMatch(<span class="hljs-string">'comment'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">elem</span>) </span>{
-  elem.where(<span class="hljs-string">'author'</span>).equals(<span class="hljs-string">'autobot'</span>);
-  elem.where(<span class="hljs-string">'votes'</span>).gte(<span class="hljs-number">5</span>);
-})
-
-query.where(<span class="hljs-string">'comment'</span>).elemMatch(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">elem</span>) </span>{
-  elem.where({ author: <span class="hljs-string">'autobot'</span> });
-  elem.where(<span class="hljs-string">'votes'</span>).gte(<span class="hljs-number">5</span>);
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-equals"><a href="#query_Query-equals">Query.prototype.equals()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies the complementary comparison value for paths specified with <code>where()</code></p>
-
-<h4>Example</h4>
-
-<pre><code>User.where(<span class="hljs-string">'age'</span>).equals(<span class="hljs-number">49</span>);
-
-<span class="hljs-comment">// is the same as</span>
-
-User.where(<span class="hljs-string">'age'</span>, <span class="hljs-number">49</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-error"><a href="#query_Query-error">Query.prototype.error()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">err
-<span class="method-type">&laquo;Error|null&raquo;</span> if set, <code>exec()</code> will fail fast before sending the query to MongoDB</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Gets/sets the error flag on this query. If this flag is not null or undefined, the <code>exec()</code> promise will reject without executing.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Query().error(); <span class="hljs-comment">// Get current error value</span>
-Query().error(<span class="hljs-literal">null</span>); <span class="hljs-comment">// Unset the current error</span>
-Query().error(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'test'</span>)); <span class="hljs-comment">// `exec()` will resolve with test</span>
-Schema.pre(<span class="hljs-string">'find'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.getQuery().userId) {
-    <span class="hljs-keyword">this</span>.error(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Not allowed to query without setting userId'</span>));
-  }
-});</code></pre>
-
-<p>Note that query casting runs <strong>after</strong> hooks, so cast errors will override custom errors.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> TestSchema = <span class="hljs-keyword">new</span> Schema({ num: <span class="hljs-built_in">Number</span> });
-<span class="hljs-keyword">var</span> TestModel = db.model(<span class="hljs-string">'Test'</span>, TestSchema);
-TestModel.find({ num: <span class="hljs-string">'not a number'</span> }).error(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'woops'</span>)).exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// `error` will be a cast error because `num` failed to cast</span>
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-estimatedDocumentCount"><a href="#query_Query-estimatedDocumentCount">Query.prototype.estimatedDocumentCount()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> passed transparently to the <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#estimatedDocumentCount">MongoDB driver</a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, count)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>estimatedDocumentCount()</code> query. Faster than using <code>countDocuments()</code> for large collections because <code>estimatedDocumentCount()</code> uses collection metadata rather than scanning the entire collection.</p>
-
-<p><code>estimatedDocumentCount()</code> does <strong>not</strong> accept a filter. <code>Model.find({ foo: bar }).estimatedDocumentCount()</code> is equivalent to <code>Model.find().estimatedDocumentCount()</code></p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>estimatedDocumentCount()</code></li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> Model.find().estimatedDocumentCount();</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-exec"><a href="#query_Query-exec">Query.prototype.exec()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[operation]
-<span class="method-type">&laquo;String|Function&raquo;</span> </li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params depend on the function being called</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> promise = query.exec();
-<span class="hljs-keyword">var</span> promise = query.exec(<span class="hljs-string">'update'</span>);
-
-query.exec(callback);
-query.exec(<span class="hljs-string">'find'</span>, callback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-exists"><a href="#query_Query-exists">Query.prototype.exists()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies an <code>$exists</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// { name: { $exists: true }}</span>
-Thing.where(<span class="hljs-string">'name'</span>).exists()
-Thing.where(<span class="hljs-string">'name'</span>).exists(<span class="hljs-literal">true</span>)
-Thing.find().exists(<span class="hljs-string">'name'</span>)
-
-<span class="hljs-comment">// { name: { $exists: false }}</span>
-Thing.where(<span class="hljs-string">'name'</span>).exists(<span class="hljs-literal">false</span>);
-Thing.find().exists(<span class="hljs-string">'name'</span>, <span class="hljs-literal">false</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-explain"><a href="#query_Query-explain">Query.prototype.explain()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[verbose]
-<span class="method-type">&laquo;String&raquo;</span> The verbosity mode. Either &#39;queryPlanner&#39;, &#39;executionStats&#39;, or &#39;allPlansExecution&#39;. The default is &#39;queryPlanner&#39;</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the <a href="https://docs.mongodb.com/manual/reference/method/cursor.explain/"><code>explain</code> option</a>, which makes this query return detailed execution stats instead of the actual query result. This method is useful for determining what index your queries use.</p>
-
-<p>Calling <code>query.explain(v)</code> is equivalent to <code>query.setOption({ explain: v })</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> Query();
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> query.find({ a: <span class="hljs-number">1</span> }).explain(<span class="hljs-string">'queryPlanner'</span>);
-<span class="hljs-built_in">console</span>.log(res);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-find"><a href="#query_Query-find">Query.prototype.find()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> mongodb selector. If not specified, returns all documents.</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Find all documents that match <code>selector</code>. The result will be an array of documents.</p>
-
-<p>If there are too many documents in the result to fit in memory, use <a href="api.html#query_Query-cursor"><code>Query.prototype.cursor()</code></a></p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Using async/await</span>
-<span class="hljs-keyword">const</span> arr = <span class="hljs-keyword">await</span> Movie.find({ year: { $gte: <span class="hljs-number">1980</span>, $lte: <span class="hljs-number">1989</span> } });
-
-<span class="hljs-comment">// Using callbacks</span>
-Movie.find({ year: { $gte: <span class="hljs-number">1980</span>, $lte: <span class="hljs-number">1989</span> } }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, arr</span>) </span>{});</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-findOne"><a href="#query_Query-findOne">Query.prototype.findOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> mongodb selector</li><li class="param">[projection]
-<span class="method-type">&laquo;Object&raquo;</span> optional fields to return</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> see <a href="http://mongoosejs.com/docs/api.html#query_Query-setOptions"><code>setOptions()</code></a></li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declares the query a findOne operation. When executed, the first found document is passed to the callback.</p>
-
-<p>Passing a <code>callback</code> executes the query. The result of the query is a single document.</p>
-
-<ul>
-<li><em>Note:</em> <code>conditions</code> is optional, and if <code>conditions</code> is null or undefined,
-mongoose will send an empty <code>findOne</code> command to MongoDB, which will return
-an arbitrary document. If you're querying by <code>_id</code>, use <code>Model.findById()</code>
-instead.</li>
-</ul>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOne()</code></li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query  = Kitten.where({ color: <span class="hljs-string">'white'</span> });
-query.findOne(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kitten</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-keyword">if</span> (kitten) {
-    <span class="hljs-comment">// doc may be null if no document matched</span>
-  }
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndDelete"><a href="#query_Query-findOneAndDelete">Query.prototype.findOneAndDelete()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a MongoDB <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findOneAndDelete/">findOneAndDelete</a> command.</p>
-
-<p>Finds a matching document, removes it, and passes the found document (if any) to the callback. Executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndDelete()</code></li>
-</ul>
-
-<p>This function differs slightly from <code>Model.findOneAndRemove()</code> in that <code>findOneAndRemove()</code> becomes a <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/">MongoDB <code>findAndModify()</code> command</a>, as opposed to a <code>findOneAndDelete()</code> command. For most mongoose use cases, this distinction is purely pedantic. You should use <code>findOneAndDelete()</code> unless you have a good reason not to.</p>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>rawResult</code>: if true, resolves to the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>A.where().findOneAndDelete(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndDelete(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.where().findOneAndDelete(conditions, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndDelete(conditions) <span class="hljs-comment">// returns Query</span>
-A.where().findOneAndDelete(callback)   <span class="hljs-comment">// executes</span>
-A.where().findOneAndDelete()           <span class="hljs-comment">// returns Query</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndRemove"><a href="#query_Query-findOneAndRemove">Query.prototype.findOneAndRemove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[conditions]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a mongodb <a href="http://www.mongodb.org/display/DOCS/findAndModify+Command">findAndModify</a> remove command.</p>
-
-<p>Finds a matching document, removes it, passing the found document (if any) to the callback. Executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndRemove()</code></li>
-</ul>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>rawResult</code>: if true, resolves to the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>A.where().findOneAndRemove(conditions, options, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndRemove(conditions, options)  <span class="hljs-comment">// return Query</span>
-A.where().findOneAndRemove(conditions, callback) <span class="hljs-comment">// executes</span>
-A.where().findOneAndRemove(conditions) <span class="hljs-comment">// returns Query</span>
-A.where().findOneAndRemove(callback)   <span class="hljs-comment">// executes</span>
-A.where().findOneAndRemove()           <span class="hljs-comment">// returns Query</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndReplace"><a href="#query_Query-findOneAndReplace">Query.prototype.findOneAndReplace()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[replacement]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="http://mongoosejs.com/docs/api.html#query_Query-lean"><code>Query.lean()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, document)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a MongoDB <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findOneAndReplace/">findOneAndReplace</a> command.</p>
-
-<p>Finds a matching document, removes it, and passes the found document (if any) to the callback. Executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndReplace()</code></li>
-</ul>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>rawResult</code>: if true, resolves to the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>A.where().findOneAndReplace(filter, replacement, options, callback); <span class="hljs-comment">// executes</span>
-A.where().findOneAndReplace(filter, replacement, options); <span class="hljs-comment">// return Query</span>
-A.where().findOneAndReplace(filter, replacement, callback); <span class="hljs-comment">// executes</span>
-A.where().findOneAndReplace(filter); <span class="hljs-comment">// returns Query</span>
-A.where().findOneAndReplace(callback); <span class="hljs-comment">// executes</span>
-A.where().findOneAndReplace(); <span class="hljs-comment">// returns Query</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-findOneAndUpdate"><a href="#query_Query-findOneAndUpdate">Query.prototype.findOneAndUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.rawResult]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.lean]
-<span class="method-type">&laquo;Object&raquo;</span> if truthy, mongoose will return the document as a plain JavaScript object rather than a mongoose document. See <a href="http://mongoosejs.com/docs/api.html#query_Query-lean"><code>Query.lean()</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, doc), <em>unless</em> <code>rawResult</code> is used, in which case params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Issues a mongodb <a href="http://www.mongodb.org/display/DOCS/findAndModify+Command">findAndModify</a> update command.</p>
-
-<p>Finds a matching document, updates it according to the <code>update</code> arg, passing any <code>options</code>, and returns the found document (if any) to the callback. The query executes if <code>callback</code> is passed.</p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>findOneAndUpdate()</code></li>
-</ul>
-
-<h4>Available options</h4>
-
-<ul>
-<li><code>new</code>: bool - if true, return the modified document rather than the original. defaults to false (changed in 4.0)</li>
-<li><code>upsert</code>: bool - creates the object if it doesn't exist. defaults to false.</li>
-<li><code>fields</code>: {Object|String} - Field selection. Equivalent to <code>.select(fields).findOneAndUpdate()</code></li>
-<li><code>sort</code>: if multiple docs are found by the conditions, sets the sort order to choose which doc to update</li>
-<li><code>maxTimeMS</code>: puts a time limit on the query - requires mongodb >= 2.6.0</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>rawResult</code>: if true, returns the <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#findAndModify">raw result from the MongoDB driver</a></li>
-<li><code>context</code> (string) if set to 'query' and <code>runValidators</code> is on, <code>this</code> will refer to the query in custom validator functions that update validation runs. Does nothing if <code>runValidators</code> is false.</li>
-</ul>
-
-<h4>Callback Signature</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// error: any errors that occurred</span>
-  <span class="hljs-comment">// doc: the document before updates are applied if `new: false`, or after updates if `new = true`</span>
-}</code></pre>
-
-<h4>Examples</h4>
-
-<pre><code>query.findOneAndUpdate(conditions, update, options, callback) <span class="hljs-comment">// executes</span>
-query.findOneAndUpdate(conditions, update, options)  <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(conditions, update, callback) <span class="hljs-comment">// executes</span>
-query.findOneAndUpdate(conditions, update)           <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(update, callback)             <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(update)                       <span class="hljs-comment">// returns Query</span>
-query.findOneAndUpdate(callback)                     <span class="hljs-comment">// executes</span>
-query.findOneAndUpdate()                             <span class="hljs-comment">// returns Query</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-geometry"><a href="#query_Query-geometry">Query.prototype.geometry()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">object
-<span class="method-type">&laquo;Object&raquo;</span> Must contain a <code>type</code> property which is a String and a <code>coordinates</code> property which is an Array. See the examples.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$geometry</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> polyA = [[[ <span class="hljs-number">10</span>, <span class="hljs-number">20</span> ], [ <span class="hljs-number">10</span>, <span class="hljs-number">40</span> ], [ <span class="hljs-number">30</span>, <span class="hljs-number">40</span> ], [ <span class="hljs-number">30</span>, <span class="hljs-number">20</span> ]]]
-query.where(<span class="hljs-string">'loc'</span>).within().geometry({ type: <span class="hljs-string">'Polygon'</span>, coordinates: polyA })
-
-<span class="hljs-comment">// or</span>
-<span class="hljs-keyword">var</span> polyB = [[ <span class="hljs-number">0</span>, <span class="hljs-number">0</span> ], [ <span class="hljs-number">1</span>, <span class="hljs-number">1</span> ]]
-query.where(<span class="hljs-string">'loc'</span>).within().geometry({ type: <span class="hljs-string">'LineString'</span>, coordinates: polyB })
-
-<span class="hljs-comment">// or</span>
-<span class="hljs-keyword">var</span> polyC = [ <span class="hljs-number">0</span>, <span class="hljs-number">0</span> ]
-query.where(<span class="hljs-string">'loc'</span>).within().geometry({ type: <span class="hljs-string">'Point'</span>, coordinates: polyC })
-
-<span class="hljs-comment">// or</span>
-query.where(<span class="hljs-string">'loc'</span>).intersects().geometry({ type: <span class="hljs-string">'Point'</span>, coordinates: polyC })</code></pre>
-
-<p>The argument is assigned to the most recent path passed to <code>where()</code>.</p>
-
-<h4>NOTE:</h4>
-
-<p><code>geometry()</code> <strong>must</strong> come after either <code>intersects()</code> or <code>within()</code>.</p>
-
-<p>The <code>object</code> argument must contain <code>type</code> and <code>coordinates</code> properties. - type {String} - coordinates {Array}</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-getFilter"><a href="#query_Query-getFilter">Query.prototype.getFilter()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> current query filter</li></ul><div><p>Returns the current query filter (also known as conditions) as a POJO.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> Query();
-query.find({ a: <span class="hljs-number">1</span> }).where(<span class="hljs-string">'b'</span>).gt(<span class="hljs-number">2</span>);
-query.getFilter(); <span class="hljs-comment">// { a: 1, b: { $gt: 2 } }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-getOptions"><a href="#query_Query-getOptions">Query.prototype.getOptions()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the options</li></ul><div><p>Gets query options.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.limit(<span class="hljs-number">10</span>);
-query.setOptions({ maxTimeMS: <span class="hljs-number">1000</span> })
-query.getOptions(); <span class="hljs-comment">// { limit: 10, maxTimeMS: 1000 }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-getPopulatedPaths"><a href="#query_Query-getPopulatedPaths">Query.prototype.getPopulatedPaths()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> an array of strings representing populated paths</li></ul><div><p>Gets a list of paths to be populated by this query</p>
-
-<h4>Example:</h4>
-
-<pre><code>bookSchema.pre(<span class="hljs-string">'findOne'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-   <span class="hljs-keyword">let</span> keys = <span class="hljs-keyword">this</span>.getPopulatedPaths(); <span class="hljs-comment">// ['author']</span>
- });
- ...
- Book.findOne({}).populate(<span class="hljs-string">'author'</span>);</code></pre>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Deep populate</span>
- <span class="hljs-keyword">const</span> q = L1.find().populate({
-   path: <span class="hljs-string">'level2'</span>,
-   populate: { path: <span class="hljs-string">'level3'</span> }
- });
- q.getPopulatedPaths(); <span class="hljs-comment">// ['level2', 'level2.level3']</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-getQuery"><a href="#query_Query-getQuery">Query.prototype.getQuery()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> current query filter</li></ul><div><p>Returns the current query filter. Equivalent to <code>getFilter()</code>.</p>
-
-<p>You should use <code>getFilter()</code> instead of <code>getQuery()</code> where possible. <code>getQuery()</code> will likely be deprecated in a future release.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.find({ a: <span class="hljs-number">1</span> }).where(<span class="hljs-string">'b'</span>).gt(<span class="hljs-number">2</span>);
-query.getQuery(); <span class="hljs-comment">// { a: 1, b: { $gt: 2 } }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-getUpdate"><a href="#query_Query-getUpdate">Query.prototype.getUpdate()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> current update operations</li></ul><div><p>Returns the current update operations as a JSON object.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.update({}, { $set: { a: <span class="hljs-number">5</span> } });
-query.getUpdate(); <span class="hljs-comment">// { $set: { a: 5 } }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-gt"><a href="#query_Query-gt">Query.prototype.gt()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$gt</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>
-
-<h4>Example</h4>
-
-<pre><code>Thing.find().where(<span class="hljs-string">'age'</span>).gt(<span class="hljs-number">21</span>)
-
-<span class="hljs-comment">// or</span>
-Thing.find().gt(<span class="hljs-string">'age'</span>, <span class="hljs-number">21</span>)</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-gte"><a href="#query_Query-gte">Query.prototype.gte()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$gte</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-hint"><a href="#query_Query-hint">Query.prototype.hint()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> a hint object</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets query hints.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.hint({ indexA: <span class="hljs-number">1</span>, indexB: <span class="hljs-number">-1</span>})</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-in"><a href="#query_Query-in">Query.prototype.in()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies an <code>$in</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-intersects"><a href="#query_Query-intersects">Query.prototype.intersects()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[arg]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declares an intersects query for <code>geometry()</code>.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'path'</span>).intersects().geometry({
-    type: <span class="hljs-string">'LineString'</span>
-  , coordinates: [[<span class="hljs-number">180.0</span>, <span class="hljs-number">11.0</span>], [<span class="hljs-number">180</span>, <span class="hljs-number">9.0</span>]]
-})
-
-query.where(<span class="hljs-string">'path'</span>).intersects({
-    type: <span class="hljs-string">'LineString'</span>
-  , coordinates: [[<span class="hljs-number">180.0</span>, <span class="hljs-number">11.0</span>], [<span class="hljs-number">180</span>, <span class="hljs-number">9.0</span>]]
-})</code></pre>
-
-<h4>NOTE:</h4>
-
-<p><strong>MUST</strong> be used after <code>where()</code>.</p>
-
-<h4>NOTE:</h4>
-
-<p>In Mongoose 3.7, <code>intersects</code> changed from a getter to a function. If you need the old syntax, use <a href="https://github.com/ebensing/mongoose-within">this</a>.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-j"><a href="#query_Query-j">Query.prototype.j()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Requests acknowledgement that this operation has been persisted to MongoDB's on-disk journal.</p>
-
-<h2>This option is only valid for operations that write to the database</h2>
-
-<ul>
-<li><code>deleteOne()</code></li>
-<li><code>deleteMany()</code></li>
-<li><code>findOneAndDelete()</code></li>
-<li><code>findOneAndReplace()</code></li>
-<li><code>findOneAndUpdate()</code></li>
-<li><code>remove()</code></li>
-<li><code>update()</code></li>
-<li><code>updateOne()</code></li>
-<li><code>updateMany()</code></li>
-</ul>
-
-<p>Defaults to the schema's <a href="/docs/guide.html#writeConcern"><code>writeConcern.j</code> option</a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).deleteOne({ name: <span class="hljs-string">'Ned Stark'</span> }).j(<span class="hljs-literal">true</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-lean"><a href="#query_Query-lean">Query.prototype.lean()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean|Object&raquo;</span> defaults to true</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the lean option.</p>
-
-<p>Documents returned from queries with the <code>lean</code> option enabled are plain javascript objects, not <a href="#document-js">Mongoose Documents</a>. They have no <code>save</code> method, getters/setters, virtuals, or other Mongoose features.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">new</span> Query().lean() <span class="hljs-comment">// true</span>
-<span class="hljs-keyword">new</span> Query().lean(<span class="hljs-literal">true</span>)
-<span class="hljs-keyword">new</span> Query().lean(<span class="hljs-literal">false</span>)
-
-<span class="hljs-keyword">const</span> docs = <span class="hljs-keyword">await</span> Model.find().lean();
-docs[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span></code></pre>
-
-<p><a href="/docs/tutorials/lean.html">Lean is great for high-performance, read-only cases</a>, especially when combined with <a href="/docs/queries.html#streaming">cursors</a>.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-limit"><a href="#query_Query-limit">Query.prototype.limit()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the maximum number of documents the query will return.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.limit(<span class="hljs-number">20</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-lt"><a href="#query_Query-lt">Query.prototype.lt()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$lt</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-lte"><a href="#query_Query-lte">Query.prototype.lte()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$lte</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-map"><a href="#query_Query-map">Query.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> function to run to transform the query result</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Runs a function <code>fn</code> and treats the return value of <code>fn</code> as the new value for the query to resolve to.</p>
-
-<p>Any functions you pass to <code>map()</code> will run <strong>after</strong> any post hooks.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> MyModel.findOne().map(res =&gt; {
-  <span class="hljs-comment">// Sets a `loadedAt` property on the doc that tells you the time the</span>
-  <span class="hljs-comment">// document was loaded.</span>
-  <span class="hljs-keyword">return</span> res == <span class="hljs-literal">null</span> ?
-    res :
-    <span class="hljs-built_in">Object</span>.assign(res, { loadedAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>() });
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-maxDistance"><a href="#query_Query-maxDistance">Query.prototype.maxDistance()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>maxDistance</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-maxScan"><a href="#query_Query-maxScan">Query.prototype.maxScan()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the maxScan option.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.maxScan(<span class="hljs-number">100</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-maxTimeMS"><a href="#query_Query-maxTimeMS">Query.prototype.maxTimeMS()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[ms]
-<span class="method-type">&laquo;Number&raquo;</span> The number of milliseconds</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the <a href="https://docs.mongodb.com/manual/reference/method/cursor.maxTimeMS/">maxTimeMS</a> option. This will tell the MongoDB server to abort if the query or write op has been running for more than <code>ms</code> milliseconds.</p>
-
-<p>Calling <code>query.maxTimeMS(v)</code> is equivalent to <code>query.setOption({ maxTimeMS: v })</code></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> query = <span class="hljs-keyword">new</span> Query();
-<span class="hljs-comment">// Throws an error 'operation exceeded time limit' as long as there's</span>
-<span class="hljs-comment">// &gt;= 1 doc in the queried collection</span>
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> query.find({ $where: <span class="hljs-string">'sleep(1000) || true'</span> }).maxTimeMS(<span class="hljs-number">100</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-maxscan"><a href="#query_Query-maxscan">Query.prototype.maxscan()</a></h3><div><p><em>DEPRECATED</em> Alias of <code>maxScan</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-merge"><a href="#query_Query-merge">Query.prototype.merge()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">source
-<span class="method-type">&laquo;Query|Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Merges another Query or conditions object into this one.</p>
-
-<p>When a Query is passed, conditions, field selection and options are merged.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-mod"><a href="#query_Query-mod">Query.prototype.mod()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Array&raquo;</span> must be of length 2, first element is <code>divisor</code>, 2nd element is <code>remainder</code>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$mod</code> condition, filters documents for documents whose <code>path</code> property is a number that is equal to <code>remainder</code> modulo <code>divisor</code>.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// All find products whose inventory is odd</span>
-Product.find().mod(<span class="hljs-string">'inventory'</span>, [<span class="hljs-number">2</span>, <span class="hljs-number">1</span>]);
-Product.find().where(<span class="hljs-string">'inventory'</span>).mod([<span class="hljs-number">2</span>, <span class="hljs-number">1</span>]);
-<span class="hljs-comment">// This syntax is a little strange, but supported.</span>
-Product.find().where(<span class="hljs-string">'inventory'</span>).mod(<span class="hljs-number">2</span>, <span class="hljs-number">1</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-mongooseOptions"><a href="#query_Query-mongooseOptions">Query.prototype.mongooseOptions()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> if specified, overwrites the current options</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the options</li></ul><div><p>Getter/setter around the current mongoose-specific options for this query Below are the current Mongoose-specific options.</p>
-
-<ul>
-<li><code>populate</code>: an array representing what paths will be populated. Should have one entry for each call to <a href="/docs/api.html#query_Query-populate"><code>Query.prototype.populate()</code></a></li>
-<li><code>lean</code>: if truthy, Mongoose will not <a href="/docs/api.html#model_Model.hydrate">hydrate</a> any documents that are returned from this query. See <a href="/docs/api.html#query_Query-lean"><code>Query.prototype.lean()</code></a> for more information.</li>
-<li><code>strict</code>: controls how Mongoose handles keys that aren't in the schema for updates. This option is <code>true</code> by default, which means Mongoose will silently strip any paths in the update that aren't in the schema. See the <a href="/docs/guide.html#strict"><code>strict</code> mode docs</a> for more information.</li>
-<li><code>strictQuery</code>: controls how Mongoose handles keys that aren't in the schema for the query <code>filter</code>. This option is <code>false</code> by default for backwards compatibility, which means Mongoose will allow <code>Model.find({ foo: 'bar' })</code> even if <code>foo</code> is not in the schema. See the <a href="/docs/guide.html#strictQuery"><code>strictQuery</code> docs</a> for more information.</li>
-<li><code>useFindAndModify</code>: used to work around the <a href="/docs/deprecations.html#-findandmodify-"><code>findAndModify()</code> deprecation warning</a></li>
-<li><code>omitUndefined</code>: delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: 'bar', baz: undefined })</code> before sending the update to the server.</li>
-<li><code>nearSphere</code>: use <code>$nearSphere</code> instead of <code>near()</code>. See the <a href="/docs/api.html#query_Query-nearSphere"><code>Query.prototype.nearSphere()</code> docs</a></li>
-</ul>
-
-<p>Mongoose maintains a separate object for internal options because Mongoose sends <code>Query.prototype.options</code> to the MongoDB server, and the above options are not relevant for the MongoDB server.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-ne"><a href="#query_Query-ne">Query.prototype.ne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$ne</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-near"><a href="#query_Query-near">Query.prototype.near()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$near</code> or <code>$nearSphere</code> condition</p>
-
-<p>These operators return documents sorted by distance.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>] });
-query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> });
-query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span>, spherical: <span class="hljs-literal">true</span> });
-query.near(<span class="hljs-string">'loc'</span>, { center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-nearSphere"><a href="#query_Query-nearSphere">Query.prototype.nearSphere()</a></h3><div><p><em>DEPRECATED</em> Specifies a <code>$nearSphere</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).nearSphere({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], maxDistance: <span class="hljs-number">5</span> });</code></pre>
-
-<p><strong>Deprecated.</strong> Use <code>query.near()</code> instead with the <code>spherical</code> option set to <code>true</code>.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).near({ center: [<span class="hljs-number">10</span>, <span class="hljs-number">10</span>], spherical: <span class="hljs-literal">true</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-nin"><a href="#query_Query-nin">Query.prototype.nin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies an <code>$nin</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-nor"><a href="#query_Query-nor">Query.prototype.nor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">array
-<span class="method-type">&laquo;Array&raquo;</span> array of conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies arguments for a <code>$nor</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.nor([{ color: <span class="hljs-string">'green'</span> }, { status: <span class="hljs-string">'ok'</span> }])</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-or"><a href="#query_Query-or">Query.prototype.or()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">array
-<span class="method-type">&laquo;Array&raquo;</span> array of conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies arguments for an <code>$or</code> condition.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.or([{ color: <span class="hljs-string">'red'</span> }, { status: <span class="hljs-string">'emergency'</span> }])</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-orFail"><a href="#query_Query-orFail">Query.prototype.orFail()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[err]
-<span class="method-type">&laquo;Function|Error&raquo;</span> optional error to throw if no docs match <code>filter</code>. If not specified, <code>orFail()</code> will throw a <code>DocumentNotFoundError</code></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Make this query throw an error if no documents match the given <code>filter</code>. This is handy for integrating with async/await, because <code>orFail()</code> saves you an extra <code>if</code> statement to check if no document was found.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Throws if no doc returned</span>
-<span class="hljs-keyword">await</span> Model.findOne({ foo: <span class="hljs-string">'bar'</span> }).orFail();
-
-<span class="hljs-comment">// Throws if no document was updated</span>
-<span class="hljs-keyword">await</span> Model.updateOne({ foo: <span class="hljs-string">'bar'</span> }, { name: <span class="hljs-string">'test'</span> }).orFail();
-
-<span class="hljs-comment">// Throws "No docs found!" error if no docs match `{ foo: 'bar' }`</span>
-<span class="hljs-keyword">await</span> Model.find({ foo: <span class="hljs-string">'bar'</span> }).orFail(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'No docs found!'</span>));
-
-<span class="hljs-comment">// Throws "Not found" error if no document was found</span>
-<span class="hljs-keyword">await</span> Model.findOneAndUpdate({ foo: <span class="hljs-string">'bar'</span> }, { name: <span class="hljs-string">'test'</span> }).
-  orFail(() =&gt; <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Not found'</span>));</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-polygon"><a href="#query_Query-polygon">Query.prototype.polygon()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String|Array&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[coordinatePairs...]
-<span class="method-type">&laquo;Array|Object&raquo;</span> </li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$polygon</code> condition</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(<span class="hljs-string">'loc'</span>).within().polygon([<span class="hljs-number">10</span>,<span class="hljs-number">20</span>], [<span class="hljs-number">13</span>, <span class="hljs-number">25</span>], [<span class="hljs-number">7</span>,<span class="hljs-number">15</span>])
-query.polygon(<span class="hljs-string">'loc'</span>, [<span class="hljs-number">10</span>,<span class="hljs-number">20</span>], [<span class="hljs-number">13</span>, <span class="hljs-number">25</span>], [<span class="hljs-number">7</span>,<span class="hljs-number">15</span>])</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-populate"><a href="#query_Query-populate">Query.prototype.populate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;Object|String&raquo;</span> either the path to populate or an object specifying all parameters</li><li class="param">[select]
-<span class="method-type">&laquo;Object|String&raquo;</span> Field selection for the population query</li><li class="param">[model]
-<span class="method-type">&laquo;Model&raquo;</span> The model you wish to use for population. If not specified, populate will look up the model by the name in the Schema&#39;s <code>ref</code> field.</li><li class="param">[match]
-<span class="method-type">&laquo;Object&raquo;</span> Conditions for the population query</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Options for the population query (sort, etc)</li><ul style="margin-top: 0.5em"><li>[options.path=null]
-<span class="method-type">&laquo;String&raquo;</span> The path to populate.</li></ul><ul style="margin-top: 0.5em"><li>[options.retainNullValues=false]
-<span class="method-type">&laquo;boolean&raquo;</span> by default, Mongoose removes null and undefined values from populated arrays. Use this option to make <code>populate()</code> retain <code>null</code> and <code>undefined</code> array entries.</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if true, Mongoose will call any getters defined on the <code>localField</code>. By default, Mongoose gets the raw value of <code>localField</code>. For example, you would need to set this option to <code>true</code> if you wanted to <a href="/docs/schematypes.html#schematype-options">add a <code>lowercase</code> getter to your <code>localField</code></a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.clone=false]
-<span class="method-type">&laquo;boolean&raquo;</span> When you do <code>BlogPost.find().populate(&#39;author&#39;)</code>, blog posts with the same author will share 1 copy of an <code>author</code> doc. Enable this option to make Mongoose clone populated docs before assigning them.</li></ul><ul style="margin-top: 0.5em"><li>[options.match=null]
-<span class="method-type">&laquo;Object|Function&raquo;</span> Add an additional filter to the populate query. Can be a filter object containing <a href="https://docs.mongodb.com/manual/tutorial/query-documents/">MongoDB query syntax</a>, or a function that returns a filter object.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies paths which should be populated with other documents.</p>
-
-<h4>Example:</h4>
-
-<pre><code>Kitten.findOne().populate(<span class="hljs-string">'owner'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kitten</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(kitten.owner.name) <span class="hljs-comment">// Max</span>
-})
-
-Kitten.find().populate({
-  path: <span class="hljs-string">'owner'</span>,
-  select: <span class="hljs-string">'name'</span>,
-  match: { color: <span class="hljs-string">'black'</span> },
-  options: { sort: { name: <span class="hljs-number">-1</span> } }
-}).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kittens</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(kittens[<span class="hljs-number">0</span>].owner.name) <span class="hljs-comment">// Zoopa</span>
-})
-
-<span class="hljs-comment">// alternatively</span>
-Kitten.find().populate(<span class="hljs-string">'owner'</span>, <span class="hljs-string">'name'</span>, <span class="hljs-literal">null</span>, {sort: { name: <span class="hljs-number">-1</span> }}).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kittens</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(kittens[<span class="hljs-number">0</span>].owner.name) <span class="hljs-comment">// Zoopa</span>
-})</code></pre>
-
-<p>Paths are populated after the query executes and a response is received. A separate query is then executed for each path specified for population. After a response for each query has also been returned, the results are passed to the callback.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-projection"><a href="#query_Query-projection">Query.prototype.projection()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|null&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Object&raquo;</span> the current projection</li></ul><div><p>Get/set the current projection (AKA fields). Pass <code>null</code> to remove the current projection.</p>
-
-<p>Unlike <code>projection()</code>, the <code>select()</code> function modifies the current projection in place. This function overwrites the existing projection.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> q = Model.find();
-q.projection(); <span class="hljs-comment">// null</span>
-
-q.select(<span class="hljs-string">'a b'</span>);
-q.projection(); <span class="hljs-comment">// { a: 1, b: 1 }</span>
-
-q.projection({ c: <span class="hljs-number">1</span> });
-q.projection(); <span class="hljs-comment">// { c: 1 }</span>
-
-q.projection(<span class="hljs-literal">null</span>);
-q.projection(); <span class="hljs-comment">// null</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-read"><a href="#query_Query-read">Query.prototype.read()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">pref
-<span class="method-type">&laquo;String&raquo;</span> one of the listed preference options or aliases</li><li class="param">[tags]
-<span class="method-type">&laquo;Array&raquo;</span> optional tags for this query</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Determines the MongoDB nodes from which to read.</p>
-
-<h4>Preferences:</h4>
-
-<pre><code>primary - (<span class="hljs-keyword">default</span>) Read <span class="hljs-keyword">from</span> primary only. Operations will produce an error <span class="hljs-keyword">if</span> primary is unavailable. Cannot be combined <span class="hljs-keyword">with</span> tags.
-secondary            Read <span class="hljs-keyword">from</span> secondary <span class="hljs-keyword">if</span> available, otherwise error.
-primaryPreferred     Read <span class="hljs-keyword">from</span> primary <span class="hljs-keyword">if</span> available, otherwise a secondary.
-secondaryPreferred   Read <span class="hljs-keyword">from</span> a secondary <span class="hljs-keyword">if</span> available, otherwise read <span class="hljs-keyword">from</span> the primary.
-nearest              All operations read <span class="hljs-keyword">from</span> among the nearest candidates, but unlike other modes, <span class="hljs-keyword">this</span> option will include both the primary and all secondaries <span class="hljs-keyword">in</span> the random selection.</code></pre>
-
-<p>Aliases</p>
-
-<pre><code>p   primary
-pp  primaryPreferred
-s   secondary
-sp  secondaryPreferred
-n   nearest</code></pre>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'primary'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'p'</span>)  <span class="hljs-comment">// same as primary</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'primaryPreferred'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'pp'</span>) <span class="hljs-comment">// same as primaryPreferred</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'secondary'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'s'</span>)  <span class="hljs-comment">// same as secondary</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'secondaryPreferred'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'sp'</span>) <span class="hljs-comment">// same as secondaryPreferred</span>
-
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'nearest'</span>)
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'n'</span>)  <span class="hljs-comment">// same as nearest</span>
-
-<span class="hljs-comment">// read from secondaries with matching tags</span>
-<span class="hljs-keyword">new</span> Query().read(<span class="hljs-string">'s'</span>, [{ dc:<span class="hljs-string">'sf'</span>, s: <span class="hljs-number">1</span> },{ dc:<span class="hljs-string">'ma'</span>, s: <span class="hljs-number">2</span> }])</code></pre>
-
-<p>Read more about how to use read preferrences <a href="http://docs.mongodb.org/manual/applications/replication/#read-preference">here</a> and <a href="http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences">here</a>.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-readConcern"><a href="#query_Query-readConcern">Query.prototype.readConcern()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">level
-<span class="method-type">&laquo;String&raquo;</span> one of the listed read concern level or their aliases</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the readConcern option for the query.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'local'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'l'</span>)  <span class="hljs-comment">// same as local</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'available'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'a'</span>)  <span class="hljs-comment">// same as available</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'majority'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'m'</span>)  <span class="hljs-comment">// same as majority</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'linearizable'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'lz'</span>) <span class="hljs-comment">// same as linearizable</span>
-
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'snapshot'</span>)
-<span class="hljs-keyword">new</span> Query().readConcern(<span class="hljs-string">'s'</span>)  <span class="hljs-comment">// same as snapshot</span></code></pre>
-
-<h4>Read Concern Level:</h4>
-
-<pre><code>local         MongoDB <span class="hljs-number">3.2</span>+ The query returns <span class="hljs-keyword">from</span> the instance <span class="hljs-keyword">with</span> no guarantee guarantee that the data has been written to a majority <span class="hljs-keyword">of</span> the replica set members (i.e. may be rolled back).
-available     MongoDB <span class="hljs-number">3.6</span>+ The query returns <span class="hljs-keyword">from</span> the instance <span class="hljs-keyword">with</span> no guarantee guarantee that the data has been written to a majority <span class="hljs-keyword">of</span> the replica set members (i.e. may be rolled back).
-majority      MongoDB <span class="hljs-number">3.2</span>+ The query returns the data that has been acknowledged by a majority <span class="hljs-keyword">of</span> the replica set members. The documents returned by the read operation are durable, even <span class="hljs-keyword">in</span> the event <span class="hljs-keyword">of</span> failure.
-linearizable  MongoDB <span class="hljs-number">3.4</span>+ The query returns data that reflects all successful majority-acknowledged writes that completed prior to the start <span class="hljs-keyword">of</span> the read operation. The query may wait <span class="hljs-keyword">for</span> concurrently executing writes to propagate to a majority <span class="hljs-keyword">of</span> replica set members before returning results.
-snapshot      MongoDB <span class="hljs-number">4.0</span>+ Only available <span class="hljs-keyword">for</span> operations within multi-<span class="hljs-built_in">document</span> transactions. Upon transaction commit <span class="hljs-keyword">with</span> write concern <span class="hljs-string">"majority"</span>, the transaction operations are guaranteed to have read <span class="hljs-keyword">from</span> a snapshot <span class="hljs-keyword">of</span> majority-committed data.</code></pre>
-
-<p>Aliases</p>
-
-<pre><code>l   local
-a   available
-m   majority
-lz  linearizable
-s   snapshot</code></pre>
-
-<p>Read more about how to use read concern <a href="https://docs.mongodb.com/manual/reference/read-concern/">here</a>.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-regex"><a href="#query_Query-regex">Query.prototype.regex()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;String|RegExp&raquo;</span> </li></ul><div><p>Specifies a <code>$regex</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-remove"><a href="#query_Query-remove">Query.prototype.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object|Query&raquo;</span> mongodb selector</li><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> optional params are (error, mongooseDeleteResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a remove() operation. <code>remove()</code> is deprecated, you should use <a href="#query_Query-deleteOne"><code>deleteOne()</code></a> or <a href="#query_Query-deleteMany"><code>deleteMany()</code></a> instead.</p>
-
-<p>This function does not trigger any middleware</p>
-
-<h4>Example</h4>
-
-<pre><code>Character.remove({ name: <span class="hljs-regexp">/Stark/</span> }, callback);</code></pre>
-
-<p>This function calls the MongoDB driver's <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove"><code>Collection#remove()</code> function</a>. The returned <a href="https://mongoosejs.com/docs/queries.html">promise</a> resolves to an object that contains 3 properties:</p>
-
-<ul>
-<li><code>ok</code>: <code>1</code> if no errors occurred</li>
-<li><code>deletedCount</code>: the number of documents deleted</li>
-<li><code>n</code>: the number of documents deleted. Equal to <code>deletedCount</code>.</li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Character.remove({ name: <span class="hljs-regexp">/Stark/</span> });
-<span class="hljs-comment">// Number of docs deleted</span>
-res.deletedCount;</code></pre>
-
-<h4>Note</h4>
-
-<p>Calling <code>remove()</code> creates a <a href="./queries.html">Mongoose query</a>, and a query does not execute until you either pass a callback, call <a href="#query_Query-then"><code>Query#then()</code></a>, or call <a href="#query_Query-exec"><code>Query#exec()</code></a>.</p>
-
-<pre><code><span class="hljs-comment">// not executed</span>
-<span class="hljs-keyword">const</span> query = Character.remove({ name: <span class="hljs-regexp">/Stark/</span> });
-
-<span class="hljs-comment">// executed</span>
-Character.remove({ name: <span class="hljs-regexp">/Stark/</span> }, callback);
-Character.remove({ name: <span class="hljs-regexp">/Stark/</span> }).remove(callback);
-
-<span class="hljs-comment">// executed without a callback</span>
-Character.exec();</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-replaceOne"><a href="#query_Query-replaceOne">Query.prototype.replaceOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as a replaceOne() operation. Same as <code>update()</code>, except MongoDB will replace the existing document and will not accept any <a href="https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern">atomic</a> operators (<code>$set</code>, etc.)</p>
-
-<p><strong>Note</strong> replaceOne will <em>not</em> fire update middleware. Use <code>pre('replaceOne')</code> and <code>post('replaceOne')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.replaceOne({ _id: <span class="hljs-number">24601</span> }, { name: <span class="hljs-string">'Jean Valjean'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>replaceOne()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="query_Query-select"><a href="#query_Query-select">Query.prototype.select()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies which document fields to include or exclude (also known as the query "projection")</p>
-
-<p>When using string syntax, prefixing a path with <code>-</code> will flag that path as excluded. When a path does not have the <code>-</code> prefix, it is included. Lastly, if a path is prefixed with <code>+</code>, it forces inclusion of the path, which is useful for paths excluded at the <a href="/docs/api.html#schematype_SchemaType-select">schema level</a>.</p>
-
-<p>A projection <em>must</em> be either inclusive or exclusive. In other words, you must either list the fields to include (which excludes all others), or list the fields to exclude (which implies all other fields are included). The <a href="https://docs.mongodb.com/manual/tutorial/project-fields-from-query-results/#suppress-id-field"><code>_id</code> field is the only exception because MongoDB includes it by default</a>.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// include a and b, exclude other fields</span>
-query.select(<span class="hljs-string">'a b'</span>);
-
-<span class="hljs-comment">// exclude c and d, include other fields</span>
-query.select(<span class="hljs-string">'-c -d'</span>);
-
-<span class="hljs-comment">// Use `+` to override schema-level `select: false` without making the</span>
-<span class="hljs-comment">// projection inclusive.</span>
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  foo: { type: <span class="hljs-built_in">String</span>, select: <span class="hljs-literal">false</span> },
-  bar: <span class="hljs-built_in">String</span>
-});
-<span class="hljs-comment">// ...</span>
-query.select(<span class="hljs-string">'+foo'</span>); <span class="hljs-comment">// Override foo's `select: false` without excluding `bar`</span>
-
-<span class="hljs-comment">// or you may use object notation, useful when</span>
-<span class="hljs-comment">// you have keys already prefixed with a "-"</span>
-query.select({ a: <span class="hljs-number">1</span>, b: <span class="hljs-number">1</span> });
-query.select({ c: <span class="hljs-number">0</span>, d: <span class="hljs-number">0</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-selected"><a href="#query_Query-selected">Query.prototype.selected()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Determines if field selection has been made.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-selectedExclusively"><a href="#query_Query-selectedExclusively">Query.prototype.selectedExclusively()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Determines if exclusive field selection has been made.</p>
-
-<pre><code>query.selectedExclusively() <span class="hljs-comment">// false</span>
-query.select(<span class="hljs-string">'-name'</span>)
-query.selectedExclusively() <span class="hljs-comment">// true</span>
-query.selectedInclusively() <span class="hljs-comment">// false</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-selectedInclusively"><a href="#query_Query-selectedInclusively">Query.prototype.selectedInclusively()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><div><p>Determines if inclusive field selection has been made.</p>
-
-<pre><code>query.selectedInclusively() <span class="hljs-comment">// false</span>
-query.select(<span class="hljs-string">'name'</span>)
-query.selectedInclusively() <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-session"><a href="#query_Query-session">Query.prototype.session()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[session]
-<span class="method-type">&laquo;ClientSession&raquo;</span> from <code>await conn.startSession()</code></li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the <a href="https://docs.mongodb.com/manual/reference/server-sessions/">MongoDB session</a> associated with this query. Sessions are how you mark a query as part of a <a href="/docs/transactions.html">transaction</a>.</p>
-
-<p>Calling <code>session(null)</code> removes the session from this query.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">await</span> mongoose.startSession();
-<span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).findOne({ name: <span class="hljs-string">'Axl Rose'</span> }).session(s);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-set"><a href="#query_Query-set">Query.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Object&raquo;</span> path or object of key/value pairs to set</li><li class="param">[val]
-<span class="method-type">&laquo;Any&raquo;</span> the value to set</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Adds a <code>$set</code> to this query's update without changing the operation. This is useful for query middleware so you can add an update regardless of whether you use <code>updateOne()</code>, <code>updateMany()</code>, <code>findOneAndUpdate()</code>, etc.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Updates `{ $set: { updatedAt: new Date() } }`</span>
-<span class="hljs-keyword">new</span> Query().updateOne({}, {}).set(<span class="hljs-string">'updatedAt'</span>, <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>());
-<span class="hljs-keyword">new</span> Query().updateMany({}, {}).set({ updatedAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>() });</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-setOptions"><a href="#query_Query-setOptions">Query.prototype.setOptions()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets query options. Some options only make sense for certain operations.</p>
-
-<h4>Options:</h4>
-
-<p>The following options are only for <code>find()</code>:</p>
-
-<ul>
-<li><a href="http://www.mongodb.org/display/DOCS/Tailable+Cursors">tailable</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsort()%7D%7D">sort</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Blimit%28%29%7D%7D">limit</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bskip%28%29%7D%7D">skip</a></li>
-<li><a href="https://docs.mongodb.org/v3.2/reference/operator/meta/maxScan/#metaOp._S_maxScan">maxscan</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7BbatchSize%28%29%7D%7D">batchSize</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24comment">comment</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%7B%7Bsnapshot%28%29%7D%7D">snapshot</a></li>
-<li><a href="http://docs.mongodb.org/manual/applications/replication/#read-preference">readPreference</a></li>
-<li><a href="http://www.mongodb.org/display/DOCS/Advanced+Queries#AdvancedQueries-%24hint">hint</a></li>
-</ul>
-
-<p>The following options are only for write operations: <code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>, <code>replaceOne()</code>, <code>findOneAndUpdate()</code>, and <code>findByIdAndUpdate()</code>:</p>
-
-<ul>
-<li><a href="https://docs.mongodb.com/manual/reference/method/db.collection.update/">upsert</a></li>
-<li><a href="https://docs.mongodb.com/manual/reference/method/db.collection.update/">writeConcern</a></li>
-<li><a href="https://mongoosejs.com/docs/guide.html#timestamps">timestamps</a>: If <code>timestamps</code> is set in the schema, set this option to <code>false</code> to skip timestamps for that particular update. Has no effect if <code>timestamps</code> is not enabled in the schema options.</li>
-<li>omitUndefined: delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: 'bar', baz: undefined })</code> before sending the update to the server.</li>
-</ul>
-
-<p>The following options are only for <code>find()</code>, <code>findOne()</code>, <code>findById()</code>, <code>findOneAndUpdate()</code>, and <code>findByIdAndUpdate()</code>:</p>
-
-<ul>
-<li><a href="./api.html#query_Query-lean">lean</a></li>
-</ul>
-
-<p>The following options are only for all operations <strong>except</strong> <code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>, <code>remove()</code>, <code>deleteOne()</code>, and <code>deleteMany()</code>:</p>
-
-<ul>
-<li><a href="https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/">maxTimeMS</a></li>
-</ul>
-
-<h2>The following options are for all operations</h2>
-
-<ul>
-<li><a href="https://docs.mongodb.com/manual/reference/collation/">collation</a></li>
-<li><a href="https://docs.mongodb.com/manual/reference/server-sessions/">session</a></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="query_Query-setQuery"><a href="#query_Query-setQuery">Query.prototype.setQuery()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">new
-<span class="method-type">&laquo;Object&raquo;</span> query conditions</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;undefined&raquo;</span> </li></ul><div><p>Sets the query conditions to the provided JSON object.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.find({ a: <span class="hljs-number">1</span> })
-query.setQuery({ a: <span class="hljs-number">2</span> });
-query.getQuery(); <span class="hljs-comment">// { a: 2 }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-setUpdate"><a href="#query_Query-setUpdate">Query.prototype.setUpdate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">new
-<span class="method-type">&laquo;Object&raquo;</span> update operation</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;undefined&raquo;</span> </li></ul><div><p>Sets the current update operation to new value.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> query = <span class="hljs-keyword">new</span> Query();
-query.update({}, { $set: { a: <span class="hljs-number">5</span> } });
-query.setUpdate({ $set: { b: <span class="hljs-number">6</span> } });
-query.getUpdate(); <span class="hljs-comment">// { $set: { b: 6 } }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-size"><a href="#query_Query-size">Query.prototype.size()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies a <code>$size</code> query condition.</p>
-
-<p>When called with one argument, the most recent path passed to <code>where()</code> is used.</p>
-
-<h4>Example</h4>
-
-<pre><code>MyModel.where(<span class="hljs-string">'tags'</span>).size(<span class="hljs-number">0</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, docs</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-
-  assert(<span class="hljs-built_in">Array</span>.isArray(docs));
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'documents with 0 tags'</span>, docs);
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-skip"><a href="#query_Query-skip">Query.prototype.skip()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> </li></ul><div><p>Specifies the number of documents to skip.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.skip(<span class="hljs-number">100</span>).limit(<span class="hljs-number">20</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-slaveOk"><a href="#query_Query-slaveOk">Query.prototype.slaveOk()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">v
-<span class="method-type">&laquo;Boolean&raquo;</span> defaults to true</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p><em>DEPRECATED</em> Sets the slaveOk option.</p>
-
-<p><strong>Deprecated</strong> in MongoDB 2.2 in favor of <a href="#query_Query-read">read preferences</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code>query.slaveOk() <span class="hljs-comment">// true</span>
-query.slaveOk(<span class="hljs-literal">true</span>)
-query.slaveOk(<span class="hljs-literal">false</span>)</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-slice"><a href="#query_Query-slice">Query.prototype.slice()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">val
-<span class="method-type">&laquo;Number&raquo;</span> number/range of elements to slice</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>$slice</code> projection for an array.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.slice(<span class="hljs-string">'comments'</span>, <span class="hljs-number">5</span>)
-query.slice(<span class="hljs-string">'comments'</span>, <span class="hljs-number">-5</span>)
-query.slice(<span class="hljs-string">'comments'</span>, [<span class="hljs-number">10</span>, <span class="hljs-number">5</span>])
-query.where(<span class="hljs-string">'comments'</span>).slice(<span class="hljs-number">5</span>)
-query.where(<span class="hljs-string">'comments'</span>).slice([<span class="hljs-number">-10</span>, <span class="hljs-number">5</span>])</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-snapshot"><a href="#query_Query-snapshot">Query.prototype.snapshot()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies this query as a <code>snapshot</code> query.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.snapshot() <span class="hljs-comment">// true</span>
-query.snapshot(<span class="hljs-literal">true</span>)
-query.snapshot(<span class="hljs-literal">false</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-sort"><a href="#query_Query-sort">Query.prototype.sort()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">arg
-<span class="method-type">&laquo;Object|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the sort order</p>
-
-<p>If an object is passed, values allowed are <code>asc</code>, <code>desc</code>, <code>ascending</code>, <code>descending</code>, <code>1</code>, and <code>-1</code>.</p>
-
-<p>If a string is passed, it must be a space delimited list of path names. The sort order of each path is ascending unless the path name is prefixed with <code>-</code> which will be treated as descending.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// sort by "field" ascending and "test" descending</span>
-query.sort({ field: <span class="hljs-string">'asc'</span>, test: <span class="hljs-number">-1</span> });
-
-<span class="hljs-comment">// equivalent</span>
-query.sort(<span class="hljs-string">'field -test'</span>);</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-tailable"><a href="#query_Query-tailable">Query.prototype.tailable()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> defaults to true</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> options to set</li><ul style="margin-top: 0.5em"><li>[opts.numberOfRetries]
-<span class="method-type">&laquo;Number&raquo;</span> if cursor is exhausted, retry this many times before giving up</li></ul><ul style="margin-top: 0.5em"><li>[opts.tailableRetryInterval]
-<span class="method-type">&laquo;Number&raquo;</span> if cursor is exhausted, wait this many milliseconds before retrying</li></ul></ul><div><p>Sets the tailable option (for use with capped collections).</p>
-
-<h4>Example</h4>
-
-<pre><code>query.tailable() <span class="hljs-comment">// true</span>
-query.tailable(<span class="hljs-literal">true</span>)
-query.tailable(<span class="hljs-literal">false</span>)</code></pre>
-
-<h4>Note</h4>
-
-<p>Cannot be used with <code>distinct()</code></p>  </div><hr class="separate-api-elements"><h3 id="query_Query-then"><a href="#query_Query-then">Query.prototype.then()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[resolve]
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[reject]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Executes the query returning a <code>Promise</code> which will be resolved with either the doc(s) or rejected with the error.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-toConstructor"><a href="#query_Query-toConstructor">Query.prototype.toConstructor()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> subclass-of-Query</li></ul><div><p>Converts this query to a customized, reusable query constructor with all arguments and options retained.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Create a query for adventure movies and read from the primary</span>
-<span class="hljs-comment">// node in the replica-set unless it is down, in which case we'll</span>
-<span class="hljs-comment">// read from a secondary node.</span>
-<span class="hljs-keyword">var</span> query = Movie.find({ tags: <span class="hljs-string">'adventure'</span> }).read(<span class="hljs-string">'primaryPreferred'</span>);
-
-<span class="hljs-comment">// create a custom Query constructor based off these settings</span>
-<span class="hljs-keyword">var</span> Adventure = query.toConstructor();
-
-<span class="hljs-comment">// Adventure is now a subclass of mongoose.Query and works the same way but with the</span>
-<span class="hljs-comment">// default query parameters and options set.</span>
-Adventure().exec(callback)
-
-<span class="hljs-comment">// further narrow down our query results while still using the previous settings</span>
-Adventure().where({ name: <span class="hljs-regexp">/^Life/</span> }).exec(callback);
-
-<span class="hljs-comment">// since Adventure is a stand-alone constructor we can also add our own</span>
-<span class="hljs-comment">// helper methods and getters without impacting global queries</span>
-Adventure.prototype.startsWith = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">prefix</span>) </span>{
-  <span class="hljs-keyword">this</span>.where({ name: <span class="hljs-keyword">new</span> <span class="hljs-built_in">RegExp</span>(<span class="hljs-string">'^'</span> + prefix) })
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>;
-}
-<span class="hljs-built_in">Object</span>.defineProperty(Adventure.prototype, <span class="hljs-string">'highlyRated'</span>, {
-  get: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-    <span class="hljs-keyword">this</span>.where({ rating: { $gt: <span class="hljs-number">4.5</span> }});
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>;
-  }
-})
-Adventure().highlyRated.startsWith(<span class="hljs-string">'Life'</span>).exec(callback)</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-update"><a href="#query_Query-update">Query.prototype.update()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as an update() operation.</p>
-
-<p><em>All paths passed that are not <a href="https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern">atomic</a> operations will become <code>$set</code> ops.</em></p>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>update()</code></li>
-</ul>
-
-<h4>Example</h4>
-
-<pre><code>Model.where({ _id: id }).update({ title: <span class="hljs-string">'words'</span> })
-
-<span class="hljs-comment">// becomes</span>
-
-Model.where({ _id: id }).update({ $set: { title: <span class="hljs-string">'words'</span> }})</code></pre>
-
-<h4>Valid options:</h4>
-
-<ul>
-<li><code>upsert</code> (boolean) whether to create the doc if it doesn't match (false)</li>
-<li><code>multi</code> (boolean) whether multiple documents should be updated (false)</li>
-<li><code>runValidators</code>: if true, runs <a href="/docs/validation.html#update-validators">update validators</a> on this command. Update validators validate the update operation against the model's schema.</li>
-<li><code>setDefaultsOnInsert</code>: if this and <code>upsert</code> are true, mongoose will apply the <a href="http://mongoosejs.com/docs/defaults.html">defaults</a> specified in the model's schema if a new document is created. This option only works on MongoDB >= 2.4 because it relies on <a href="https://docs.mongodb.org/v2.4/reference/operator/update/setOnInsert/">MongoDB's <code>$setOnInsert</code> operator</a>.</li>
-<li><code>strict</code> (boolean) overrides the <code>strict</code> option for this update</li>
-<li><code>overwrite</code> (boolean) disables update-only mode, allowing you to overwrite the doc (false)</li>
-<li><code>context</code> (string) if set to 'query' and <code>runValidators</code> is on, <code>this</code> will refer to the query in custom validator functions that update validation runs. Does nothing if <code>runValidators</code> is false.</li>
-<li><code>read</code></li>
-<li><code>writeConcern</code></li>
-</ul>
-
-<h4>Note</h4>
-
-<p>Passing an empty object <code>{}</code> as the doc will result in a no-op unless the <code>overwrite</code> option is passed. Without the <code>overwrite</code> option set, the update operation will be ignored and the callback executed without sending the command to MongoDB so as to prevent accidently overwritting documents in the collection.</p>
-
-<h4>Note</h4>
-
-<p>The operation is only executed when a callback is passed. To force execution without a callback, we must first call update() and then execute it by using the <code>exec()</code> method.</p>
-
-<pre><code>var q = Model.where({ _id: id });
-q.update({ $set: { name: 'bob' }}).update(); // not executed
-
-q.update({ $set: { name: 'bob' }}).exec(); // executed
-
-// keys that are not [atomic](<a href='https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern'>https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern</a>) ops become `$set`.
-// this executes the same command as the previous example.
-q.update({ name: 'bob' }).exec();
-
-// overwriting with empty docs
-var q = Model.where({ _id: id }).setOptions({ overwrite: true })
-q.update({ }, callback); // executes
-
-// multi update with overwrite to empty doc
-var q = Model.where({ _id: id });
-q.setOptions({ multi: true, overwrite: true })
-q.update({ });
-q.update(callback); // executed
-
-// multi updates
-Model.where()
-     .update({ name: /^match/ }, { $set: { arr: [] }}, { multi: true }, callback)
-
-// more multi updates
-Model.where()
-     .setOptions({ multi: true })
-     .update({ $set: { arr: [] }}, callback)
-
-// single update by default
-Model.where({ email: '<a href='mailto:address@example.com'>address@example.com</a>' })
-     .update({ $inc: { counter: 1 }}, callback)
-</code></pre>
-
-<p>API summary</p>
-
-<pre><code>update(filter, doc, options, cb) <span class="hljs-comment">// executes</span>
-update(filter, doc, options)
-update(filter, doc, cb) <span class="hljs-comment">// executes</span>
-update(filter, doc)
-update(doc, cb) <span class="hljs-comment">// executes</span>
-update(doc)
-update(cb) <span class="hljs-comment">// executes</span>
-update(<span class="hljs-literal">true</span>) <span class="hljs-comment">// executes</span>
-update()</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-updateMany"><a href="#query_Query-updateMany">Query.prototype.updateMany()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as an updateMany() operation. Same as <code>update()</code>, except MongoDB will update <em>all</em> documents that match <code>filter</code> (as opposed to just the first one) regardless of the value of the <code>multi</code> option.</p>
-
-<p><strong>Note</strong> updateMany will <em>not</em> fire update middleware. Use <code>pre('updateMany')</code> and <code>post('updateMany')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateMany({ name: <span class="hljs-regexp">/Stark$/</span> }, { isDeleted: <span class="hljs-literal">true</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateMany()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="query_Query-updateOne"><a href="#query_Query-updateOne">Query.prototype.updateOne()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[filter]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[doc]
-<span class="method-type">&laquo;Object&raquo;</span> the update command</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.multipleCastError]
-<span class="method-type">&laquo;Boolean&raquo;</span> by default, mongoose only returns the first error that occurred in casting the query. Turn on this option to aggregate all the cast errors.</li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.strict]
-<span class="method-type">&laquo;Boolean|String&raquo;</span> overwrites the schema&#39;s <a href="http://mongoosejs.com/docs/guide.html#strict">strict mode option</a></li></ul><ul style="margin-top: 0.5em"><li>[options.upsert=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> if true, and no documents found, insert a new document</li></ul><ul style="margin-top: 0.5em"><li>[options.writeConcern=null]
-<span class="method-type">&laquo;Object&raquo;</span> sets the <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a> for replica sets. Overrides the <a href="/docs/guide.html#writeConcern">schema-level write concern</a></li></ul><ul style="margin-top: 0.5em"><li>[options.omitUndefined=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, delete any properties whose value is <code>undefined</code> when casting an update. In other words, if this is set, Mongoose will delete <code>baz</code> from the update in <code>Model.updateOne({}, { foo: &#39;bar&#39;, baz: undefined })</code> before sending the update to the server.</li></ul><ul style="margin-top: 0.5em"><li>[options.timestamps=null]
-<span class="method-type">&laquo;Boolean&raquo;</span> If set to <code>false</code> and <a href="/docs/guide.html#timestamps">schema-level timestamps</a> are enabled, skip timestamps for this update. Does nothing if schema-level timestamps are not set.</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> params are (error, writeOpResult)</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Declare and/or execute this query as an updateOne() operation. Same as <code>update()</code>, except it does not support the <code>multi</code> or <code>overwrite</code> options.</p>
-
-<ul>
-<li>MongoDB will update <em>only</em> the first document that matches <code>filter</code> regardless of the value of the <code>multi</code> option.</li>
-<li>Use <code>replaceOne()</code> if you want to overwrite an entire document rather than using <a href="https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern">atomic</a> operators like <code>$set</code>.</li>
-</ul>
-
-<p><strong>Note</strong> updateOne will <em>not</em> fire update middleware. Use <code>pre('updateOne')</code> and <code>post('updateOne')</code> instead.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Person.updateOne({ name: <span class="hljs-string">'Jean-Luc Picard'</span> }, { ship: <span class="hljs-string">'USS Enterprise'</span> });
-res.n; <span class="hljs-comment">// Number of documents matched</span>
-res.nModified; <span class="hljs-comment">// Number of documents modified</span></code></pre>
-
-<p>This function triggers the following middleware.</p>
-
-<ul>
-<li><code>updateOne()</code></li>
-</ul>  </div><hr class="separate-api-elements"><h3 id="query_Query-use$geoWithin"><a href="#query_Query-use$geoWithin">Query.prototype.use$geoWithin</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Flag to opt out of using <code>$geoWithin</code>.</p>
-
-<pre><code>mongoose.Query.use$geoWithin = <span class="hljs-literal">false</span>;</code></pre>
-
-<p>MongoDB 2.4 deprecated the use of <code>$within</code>, replacing it with <code>$geoWithin</code>. Mongoose uses <code>$geoWithin</code> by default (which is 100% backward compatible with <code>$within</code>). If you are running an older version of MongoDB, set this flag to <code>false</code> so your <code>within()</code> queries continue to work.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-w"><a href="#query_Query-w">Query.prototype.w()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;String|number&raquo;</span> 0 for fire-and-forget, 1 for acknowledged by one server, &#39;majority&#39; for majority of the replica set, or <a href="https://docs.mongodb.com/manual/reference/write-concern/#w-option">any of the more advanced options</a>.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Sets the specified number of <code>mongod</code> servers, or tag set of <code>mongod</code> servers, that must acknowledge this write before this write is considered successful.</p>
-
-<h2>This option is only valid for operations that write to the database</h2>
-
-<ul>
-<li><code>deleteOne()</code></li>
-<li><code>deleteMany()</code></li>
-<li><code>findOneAndDelete()</code></li>
-<li><code>findOneAndReplace()</code></li>
-<li><code>findOneAndUpdate()</code></li>
-<li><code>remove()</code></li>
-<li><code>update()</code></li>
-<li><code>updateOne()</code></li>
-<li><code>updateMany()</code></li>
-</ul>
-
-<p>Defaults to the schema's <a href="/docs/guide.html#writeConcern"><code>writeConcern.w</code> option</a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// The 'majority' option means the `deleteOne()` promise won't resolve</span>
-<span class="hljs-comment">// until the `deleteOne()` has propagated to the majority of the replica set</span>
-<span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).
-  deleteOne({ name: <span class="hljs-string">'Ned Stark'</span> }).
-  w(<span class="hljs-string">'majority'</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-where"><a href="#query_Query-where">Query.prototype.where()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[path]
-<span class="method-type">&laquo;String|Object&raquo;</span> </li><li class="param">[val]
-<span class="method-type">&laquo;any&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Specifies a <code>path</code> for use with chaining.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// instead of writing:</span>
-User.find({age: {$gte: <span class="hljs-number">21</span>, $lte: <span class="hljs-number">65</span>}}, callback);
-
-<span class="hljs-comment">// we can instead write:</span>
-User.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>);
-
-<span class="hljs-comment">// passing query conditions is permitted</span>
-User.find().where({ name: <span class="hljs-string">'vonderful'</span> })
-
-<span class="hljs-comment">// chaining</span>
-User
-.where(<span class="hljs-string">'age'</span>).gte(<span class="hljs-number">21</span>).lte(<span class="hljs-number">65</span>)
-.where(<span class="hljs-string">'name'</span>, <span class="hljs-regexp">/^vonderful/i</span>)
-.where(<span class="hljs-string">'friends'</span>).slice(<span class="hljs-number">10</span>)
-.exec(callback)</code></pre>  </div><hr class="separate-api-elements"><h3 id="query_Query-within"><a href="#query_Query-within">Query.prototype.within()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>Defines a <code>$within</code> or <code>$geoWithin</code> argument for geo-spatial queries.</p>
-
-<h4>Example</h4>
-
-<pre><code>query.where(path).within().box()
-query.where(path).within().circle()
-query.where(path).within().geometry()
-
-query.where(<span class="hljs-string">'loc'</span>).within({ center: [<span class="hljs-number">50</span>,<span class="hljs-number">50</span>], radius: <span class="hljs-number">10</span>, unique: <span class="hljs-literal">true</span>, spherical: <span class="hljs-literal">true</span> });
-query.where(<span class="hljs-string">'loc'</span>).within({ box: [[<span class="hljs-number">40.73</span>, <span class="hljs-number">-73.9</span>], [<span class="hljs-number">40.7</span>, <span class="hljs-number">-73.988</span>]] });
-query.where(<span class="hljs-string">'loc'</span>).within({ polygon: [[],[],[],[]] });
-
-query.where(<span class="hljs-string">'loc'</span>).within([], [], []) <span class="hljs-comment">// polygon</span>
-query.where(<span class="hljs-string">'loc'</span>).within([], []) <span class="hljs-comment">// box</span>
-query.where(<span class="hljs-string">'loc'</span>).within({ type: <span class="hljs-string">'LineString'</span>, coordinates: [...] }); <span class="hljs-comment">// geometry</span></code></pre>
-
-<p><strong>MUST</strong> be used after <code>where()</code>.</p>
-
-<h4>NOTE:</h4>
-
-<p>As of Mongoose 3.7, <code>$geoWithin</code> is always used for queries. To change this behavior, see <a href="#query_Query-use%2524geoWithin">Query.use$geoWithin</a>.</p>
-
-<h4>NOTE:</h4>
-
-<p>In Mongoose 3.7, <code>within</code> changed from a getter to a function. If you need the old syntax, use <a href="https://github.com/ebensing/mongoose-within">this</a>.</p>  </div><hr class="separate-api-elements"><h3 id="query_Query-wtimeout"><a href="#query_Query-wtimeout">Query.prototype.wtimeout()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ms
-<span class="method-type">&laquo;number&raquo;</span> number of milliseconds to wait</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Query&raquo;</span> this</li></ul><div><p>If <a href="/docs/api.html#query_Query-w"><code>w > 1</code></a>, the maximum amount of time to wait for this write to propagate through the replica set before this operation fails. The default is <code>0</code>, which means no timeout.</p>
-
-<h2>This option is only valid for operations that write to the database</h2>
-
-<ul>
-<li><code>deleteOne()</code></li>
-<li><code>deleteMany()</code></li>
-<li><code>findOneAndDelete()</code></li>
-<li><code>findOneAndReplace()</code></li>
-<li><code>findOneAndUpdate()</code></li>
-<li><code>remove()</code></li>
-<li><code>update()</code></li>
-<li><code>updateOne()</code></li>
-<li><code>updateMany()</code></li>
-</ul>
-
-<p>Defaults to the schema's <a href="/docs/guide.html#writeConcern"><code>writeConcern.wtimeout</code> option</a></p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// The `deleteOne()` promise won't resolve until this `deleteOne()` has</span>
-<span class="hljs-comment">// propagated to at least `w = 2` members of the replica set. If it takes</span>
-<span class="hljs-comment">// longer than 1 second, this `deleteOne()` will fail.</span>
-<span class="hljs-keyword">await</span> mongoose.model(<span class="hljs-string">'Person'</span>).
-  deleteOne({ name: <span class="hljs-string">'Ned Stark'</span> }).
-  w(<span class="hljs-number">2</span>).
-  wtimeout(<span class="hljs-number">1000</span>);</code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/querycursor.html b/docs/api/querycursor.html
deleted file mode 100644
index 98f3e5ad8fe..00000000000
--- a/docs/api/querycursor.html
+++ /dev/null
@@ -1,106 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>QueryCursor</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title" style="font-weight: bold"><a href="querycursor.html">QueryCursor</a></div><ul class="nav-item-sub"><li><a href="#querycursor_QueryCursor">QueryCursor()</a></li><li><a href="#querycursor_QueryCursor-addCursorFlag">QueryCursor.prototype.addCursorFlag()</a></li><li><a href="#querycursor_QueryCursor-close">QueryCursor.prototype.close()</a></li><li><a href="#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></li><li><a href="#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></li><li><a href="#querycursor_QueryCursor-next">QueryCursor.prototype.next()</a></li></ul></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#querycursor_QueryCursor">QueryCursor()</a></li><li><a href="#querycursor_QueryCursor-addCursorFlag">QueryCursor.prototype.addCursorFlag()</a></li><li><a href="#querycursor_QueryCursor-close">QueryCursor.prototype.close()</a></li><li><a href="#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></li><li><a href="#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></li><li><a href="#querycursor_QueryCursor-next">QueryCursor.prototype.next()</a></li></ul><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor"><a href="#querycursor_QueryCursor">QueryCursor()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">query
-<span class="method-type">&laquo;Query&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> query options passed to <code>.find()</code></li></ul><div><p>A QueryCursor is a concurrency primitive for processing query results one document at a time. A QueryCursor fulfills the Node.js streams3 API, in addition to several other mechanisms for loading documents from MongoDB one at a time.</p>
-
-<p>QueryCursors execute the model's pre find hooks, but <strong>not</strong> the model's post find hooks.</p>
-
-<p>Unless you're an advanced user, do <strong>not</strong> instantiate this class directly. Use <a href="/docs/api.html#query_Query-cursor"><code>Query#cursor()</code></a> instead.</p>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-addCursorFlag"><a href="#querycursor_QueryCursor-addCursorFlag">QueryCursor.prototype.addCursorFlag()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">flag
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">value
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;AggregationCursor&raquo;</span> this</li></ul><div><p>Adds a <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Cursor.html#addCursorFlag">cursor flag</a>. Useful for setting the <code>noCursorTimeout</code> and <code>tailable</code> flags.</p>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-close"><a href="#querycursor_QueryCursor-close">QueryCursor.prototype.close()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Marks this cursor as closed. Will stop streaming and subsequent calls to <code>next()</code> will error.</p>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-eachAsync"><a href="#querycursor_QueryCursor-eachAsync">QueryCursor.prototype.eachAsync()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.parallel]
-<span class="method-type">&laquo;Number&raquo;</span> the number of promises to execute in parallel. Defaults to 1.
-<span class="method-type">&laquo;Object&raquo;</span><ul style="margin-top: 0.5em"><li>[options.batchSize]
-  <span class="method-type">&laquo;Number&raquo;</span> The size of documents processed by the passed in function to eachAsync (works with the parallel option)</li></ul>
-</li></ul><li class="param">[callback]
-<span class="method-type">&laquo;Function&raquo;</span> executed when all docs have been processed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Execute <code>fn</code> for every document in the cursor. If <code>fn</code> returns a promise, will wait for the promise to resolve before iterating on to the next one. Returns a promise that resolves when done.</p>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-map"><a href="#querycursor_QueryCursor-map">QueryCursor.prototype.map()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;QueryCursor&raquo;</span> </li></ul><div><p>Registers a transform function which subsequently maps documents retrieved via the streams interface or <code>.next()</code></p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-comment">// Map documents returned by `data` events</span>
-Thing.
-  find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-   doc.foo = <span class="hljs-string">"bar"</span>;
-   <span class="hljs-keyword">return</span> doc;
-  })
-  on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{ <span class="hljs-built_in">console</span>.log(doc.foo); });
-
-<span class="hljs-comment">// Or map documents returned by `.next()`</span>
-<span class="hljs-keyword">var</span> cursor = Thing.find({ name: <span class="hljs-regexp">/^hello/</span> }).
-  cursor().
-  map(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-    doc.foo = <span class="hljs-string">"bar"</span>;
-    <span class="hljs-keyword">return</span> doc;
-  });
-cursor.next(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(doc.foo);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="querycursor_QueryCursor-next"><a href="#querycursor_QueryCursor-next">QueryCursor.prototype.next()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Promise&raquo;</span> </li></ul><div><p>Get the next document from this cursor. Will return <code>null</code> when there are no documents left.</p>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/schema.html b/docs/api/schema.html
deleted file mode 100644
index 37ca7ed187f..00000000000
--- a/docs/api/schema.html
+++ /dev/null
@@ -1,426 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Schema</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title" style="font-weight: bold"><a href="schema.html">Schema</a></div><ul class="nav-item-sub"><li><a href="#schema_Schema">Schema()</a></li><li><a href="#schema_Schema.Types">Schema.Types</a></li><li><a href="#schema_Schema-indexTypes">Schema.indexTypes</a></li><li><a href="#schema_Schema-add">Schema.prototype.add()</a></li><li><a href="#schema_Schema-childSchemas">Schema.prototype.childSchemas</a></li><li><a href="#schema_Schema-clone">Schema.prototype.clone()</a></li><li><a href="#schema_Schema-eachPath">Schema.prototype.eachPath()</a></li><li><a href="#schema_Schema-get">Schema.prototype.get()</a></li><li><a href="#schema_Schema-index">Schema.prototype.index()</a></li><li><a href="#schema_Schema-indexes">Schema.prototype.indexes()</a></li><li><a href="#schema_Schema-loadClass">Schema.prototype.loadClass()</a></li><li><a href="#schema_Schema-method">Schema.prototype.method()</a></li><li><a href="#schema_Schema-obj">Schema.prototype.obj</a></li><li><a href="#schema_Schema-path">Schema.prototype.path()</a></li><li><a href="#schema_Schema-pathType">Schema.prototype.pathType()</a></li><li><a href="#schema_Schema-plugin">Schema.prototype.plugin()</a></li><li><a href="#schema_Schema-post">Schema.prototype.post()</a></li><li><a href="#schema_Schema-pre">Schema.prototype.pre()</a></li><li><a href="#schema_Schema-queue">Schema.prototype.queue()</a></li><li><a href="#schema_Schema-remove">Schema.prototype.remove()</a></li><li><a href="#schema_Schema-requiredPaths">Schema.prototype.requiredPaths()</a></li><li><a href="#schema_Schema-set">Schema.prototype.set()</a></li><li><a href="#schema_Schema-static">Schema.prototype.static()</a></li><li><a href="#schema_Schema-virtual">Schema.prototype.virtual()</a></li><li><a href="#schema_Schema-virtualpath">Schema.prototype.virtualpath()</a></li><li><a href="#schema_Schema.reserved">Schema.reserved</a></li></ul></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#schema_Schema">Schema()</a></li><li><a href="#schema_Schema.Types">Schema.Types</a></li><li><a href="#schema_Schema-indexTypes">Schema.indexTypes</a></li><li><a href="#schema_Schema-add">Schema.prototype.add()</a></li><li><a href="#schema_Schema-childSchemas">Schema.prototype.childSchemas</a></li><li><a href="#schema_Schema-clone">Schema.prototype.clone()</a></li><li><a href="#schema_Schema-eachPath">Schema.prototype.eachPath()</a></li><li><a href="#schema_Schema-get">Schema.prototype.get()</a></li><li><a href="#schema_Schema-index">Schema.prototype.index()</a></li><li><a href="#schema_Schema-indexes">Schema.prototype.indexes()</a></li><li><a href="#schema_Schema-loadClass">Schema.prototype.loadClass()</a></li><li><a href="#schema_Schema-method">Schema.prototype.method()</a></li><li><a href="#schema_Schema-obj">Schema.prototype.obj</a></li><li><a href="#schema_Schema-path">Schema.prototype.path()</a></li><li><a href="#schema_Schema-pathType">Schema.prototype.pathType()</a></li><li><a href="#schema_Schema-plugin">Schema.prototype.plugin()</a></li><li><a href="#schema_Schema-post">Schema.prototype.post()</a></li><li><a href="#schema_Schema-pre">Schema.prototype.pre()</a></li><li><a href="#schema_Schema-queue">Schema.prototype.queue()</a></li><li><a href="#schema_Schema-remove">Schema.prototype.remove()</a></li><li><a href="#schema_Schema-requiredPaths">Schema.prototype.requiredPaths()</a></li><li><a href="#schema_Schema-set">Schema.prototype.set()</a></li><li><a href="#schema_Schema-static">Schema.prototype.static()</a></li><li><a href="#schema_Schema-virtual">Schema.prototype.virtual()</a></li><li><a href="#schema_Schema-virtualpath">Schema.prototype.virtualpath()</a></li><li><a href="#schema_Schema.reserved">Schema.reserved</a></li></ul><hr class="separate-api-elements"><h3 id="schema_Schema"><a href="#schema_Schema">Schema()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">[definition]
-<span class="method-type">&laquo;Object|Schema|Array&raquo;</span> Can be one of: object describing schema paths, or schema to copy, or array of objects and schemas</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Schema constructor.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> child = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, age: <span class="hljs-built_in">Number</span>, children: [child] });
-<span class="hljs-keyword">var</span> Tree = mongoose.model(<span class="hljs-string">'Tree'</span>, schema);
-
-<span class="hljs-comment">// setting schema options</span>
-<span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { _id: <span class="hljs-literal">false</span>, autoIndex: <span class="hljs-literal">false</span> })</code></pre>
-
-<h4>Options:</h4>
-
-<ul>
-<li><a href="/docs/guide.html#autoIndex">autoIndex</a>: bool - defaults to null (which means use the connection's autoIndex option)</li>
-<li><a href="/docs/guide.html#autoCreate">autoCreate</a>: bool - defaults to null (which means use the connection's autoCreate option)</li>
-<li><a href="/docs/guide.html#bufferCommands">bufferCommands</a>: bool - defaults to true</li>
-<li><a href="/docs/guide.html#capped">capped</a>: bool - defaults to false</li>
-<li><a href="/docs/guide.html#collection">collection</a>: string - no default</li>
-<li><a href="/docs/guide.html#id">id</a>: bool - defaults to true</li>
-<li><a href="/docs/guide.html#_id">_id</a>: bool - defaults to true</li>
-<li><code>minimize</code>: bool - controls <a href="#document_Document-toObject">document#toObject</a> behavior when called manually - defaults to true</li>
-<li><a href="/docs/guide.html#read">read</a>: string</li>
-<li><a href="/docs/guide.html#writeConcern">writeConcern</a>: object - defaults to null, use to override <a href="https://docs.mongodb.com/manual/reference/write-concern/">the MongoDB server's default write concern settings</a></li>
-<li><a href="/docs/guide.html#shardKey">shardKey</a>: object - defaults to <code>null</code></li>
-<li><a href="/docs/guide.html#strict">strict</a>: bool - defaults to true</li>
-<li><a href="/docs/guide.html#strictQuery">strictQuery</a>: bool - defaults to false</li>
-<li><a href="/docs/guide.html#toJSON">toJSON</a> - object - no default</li>
-<li><a href="/docs/guide.html#toObject">toObject</a> - object - no default</li>
-<li><a href="/docs/guide.html#typeKey">typeKey</a> - string - defaults to 'type'</li>
-<li><a href="/docs/guide.html#useNestedStrict">useNestedStrict</a> - boolean - defaults to false</li>
-<li><a href="/docs/guide.html#validateBeforeSave">validateBeforeSave</a> - bool - defaults to <code>true</code></li>
-<li><a href="/docs/guide.html#versionKey">versionKey</a>: string - defaults to "__v"</li>
-<li><a href="/docs/guide.html#collation">collation</a>: object - defaults to null (which means use no collation)</li>
-<li><a href="/docs/guide.html#selectPopulatedPaths">selectPopulatedPaths</a>: boolean - defaults to <code>true</code></li>
-<li><a href="/docs/guide.html#skipVersioning">skipVersioning</a>: object - paths to exclude from versioning</li>
-<li><a href="/docs/guide.html#timestamps">timestamps</a>: object or boolean - defaults to <code>false</code>. If true, Mongoose adds <code>createdAt</code> and <code>updatedAt</code> properties to your schema and manages those properties for you.</li>
-<li><a href="/docs/guide.html#storeSubdocValidationError">storeSubdocValidationError</a>: boolean - Defaults to true. If false, Mongoose will wrap validation errors in single nested document subpaths into a single validation error on the single nested subdoc's path.</li>
-</ul>
-
-<h4>Note:</h4>
-
-<p><em>When nesting schemas, (<code>children</code> in the example above), always declare the child schema first before passing it into its parent.</em></p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema.Types"><a href="#schema_Schema.Types">Schema.Types</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The various built-in Mongoose Schema Types.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> ObjectId = mongoose.Schema.Types.ObjectId;</code></pre>
-
-<h4>Types:</h4>
-
-<ul>
-<li><a href="#schema-string-js">String</a></li>
-<li><a href="#schema-number-js">Number</a></li>
-<li><a href="#schema-boolean-js">Boolean</a> | Bool</li>
-<li><a href="#schema-array-js">Array</a></li>
-<li><a href="#schema-buffer-js">Buffer</a></li>
-<li><a href="#schema-date-js">Date</a></li>
-<li><a href="#schema-objectid-js">ObjectId</a> | Oid</li>
-<li><a href="#schema-mixed-js">Mixed</a></li>
-</ul>
-
-<p>Using this exposed access to the <code>Mixed</code> SchemaType, we can use them in our schema.</p>
-
-<pre><code><span class="hljs-keyword">var</span> Mixed = mongoose.Schema.Types.Mixed;
-<span class="hljs-keyword">new</span> mongoose.Schema({ _user: Mixed })</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-indexTypes"><a href="#schema_Schema-indexTypes">Schema.indexTypes</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The allowed index types</p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-add"><a href="#schema_Schema-add">Schema.prototype.add()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;Object|Schema&raquo;</span> plain object with paths to add, or another schema</li><li class="param">[prefix]
-<span class="method-type">&laquo;String&raquo;</span> path to prefix the newly added paths with</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> the Schema instance</li></ul><div><p>Adds key path / schema type pairs to this schema.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> ToySchema = <span class="hljs-keyword">new</span> Schema();
-ToySchema.add({ name: <span class="hljs-string">'string'</span>, color: <span class="hljs-string">'string'</span>, price: <span class="hljs-string">'number'</span> });
-
-<span class="hljs-keyword">const</span> TurboManSchema = <span class="hljs-keyword">new</span> Schema();
-<span class="hljs-comment">// You can also `add()` another schema and copy over all paths, virtuals,</span>
-<span class="hljs-comment">// getters, setters, indexes, methods, and statics.</span>
-TurboManSchema.add(ToySchema).add({ year: <span class="hljs-built_in">Number</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-childSchemas"><a href="#schema_Schema-childSchemas">Schema.prototype.childSchemas</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Array of child schemas (from document arrays and single nested subdocs) and their corresponding compiled models. Each element of the array is an object with 2 properties: <code>schema</code> and <code>model</code>.</p>
-
-<p>This property is typically only useful for plugin authors and advanced users. You do not need to interact with this property at all to use mongoose.</p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-clone"><a href="#schema_Schema-clone">Schema.prototype.clone()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> the cloned schema</li></ul><div><p>Returns a deep copy of the schema</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> clone = schema.clone();
-clone === schema; <span class="hljs-comment">// false</span>
-clone.path(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// SchemaString { ... }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-eachPath"><a href="#schema_Schema-eachPath">Schema.prototype.eachPath()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> callback function</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> this</li></ul><div><p>Iterates the schemas paths similar to Array#forEach.</p>
-
-<p>The callback is passed the pathname and the schemaType instance.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, registeredAt: <span class="hljs-built_in">Date</span> });
-userSchema.eachPath((pathname, schematype) =&gt; {
-  <span class="hljs-comment">// Prints twice:</span>
-  <span class="hljs-comment">// name SchemaString { ... }</span>
-  <span class="hljs-comment">// registeredAt SchemaDate { ... }</span>
-  <span class="hljs-built_in">console</span>.log(pathname, schematype);
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-get"><a href="#schema_Schema-get">Schema.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> option name</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Any&raquo;</span> the option&#39;s value</li></ul><div><p>Gets a schema option.</p>
-
-<h4>Example:</h4>
-
-<pre><code>schema.get(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// true</span>
-schema.set(<span class="hljs-string">'strict'</span>, <span class="hljs-literal">false</span>);
-schema.get(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// false</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-index"><a href="#schema_Schema-index">Schema.prototype.index()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fields
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> Options to pass to <a href="http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#createIndex">MongoDB driver&#39;s <code>createIndex()</code> function</a></li><ul style="margin-top: 0.5em"><li>[options.expires=null]
-<span class="method-type">&laquo;String&raquo;</span> Mongoose-specific syntactic sugar, uses <a href="https://www.npmjs.com/package/ms">ms</a> to convert <code>expires</code> option into seconds for the <code>expireAfterSeconds</code> in the above link.</li></ul></ul><div><p>Defines an index (most likely compound) for this schema.</p>
-
-<h4>Example</h4>
-
-<pre><code>schema.index({ first: <span class="hljs-number">1</span>, last: <span class="hljs-number">-1</span> })</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-indexes"><a href="#schema_Schema-indexes">Schema.prototype.indexes()</a></h3><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> list of indexes defined in the schema</li></ul><div><p>Returns a list of indexes that this schema declares, via <code>schema.index()</code> or by <code>index: true</code> in a path's options.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  email: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span>, unique: <span class="hljs-literal">true</span> },
-  registeredAt: { type: <span class="hljs-built_in">Date</span>, index: <span class="hljs-literal">true</span> }
-});
-
-<span class="hljs-comment">// [ [ { email: 1 }, { unique: true, background: true } ],</span>
-<span class="hljs-comment">//   [ { registeredAt: 1 }, { background: true } ] ]</span>
-userSchema.indexes();</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-loadClass"><a href="#schema_Schema-loadClass">Schema.prototype.loadClass()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">model
-<span class="method-type">&laquo;Function&raquo;</span> </li><li class="param">[virtualsOnly]
-<span class="method-type">&laquo;Boolean&raquo;</span> if truthy, only pulls virtuals from the class, not methods or statics</li></ul><div><p>Loads an ES6 class into a schema. Maps <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set">setters</a> + <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get">getters</a>, <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static">static methods</a>, and <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes#Class_body_and_method_definitions">instance methods</a> to schema <a href="http://mongoosejs.com/docs/guide.html#virtuals">virtuals</a>, <a href="http://mongoosejs.com/docs/guide.html#statics">statics</a>, and <a href="http://mongoosejs.com/docs/guide.html#methods">methods</a>.</p>
-
-<h4>Example:</h4>
-
-<div class="highlight"><pre lang="javascript">const md5 = require('md5');
-const userSchema = new Schema({ email: String });
-class UserClass {
-  // `gravatarImage` becomes a virtual
-  get gravatarImage() {
-    const hash = md5(this.email.toLowerCase());
-    return `<a href='https://www.gravatar.com/avatar/${hash}`'>https://www.gravatar.com/avatar/${hash}`</a>;
-  }
-
-  // `getProfileUrl()` becomes a document method
-  getProfileUrl() {
-    return `<a href='https://mysite.com/${this.email}`'>https://mysite.com/${this.email}`</a>;
-  }
-
-  // `findByEmail()` becomes a static
-  static findByEmail(email) {
-    return this.findOne({ email });
-  }
-}
-
-// `schema` will now have a `gravatarImage` virtual, a `getProfileUrl()` method,
-// and a `findByEmail()` static
-userSchema.loadClass(UserClass);
-</pre></div>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-method"><a href="#schema_Schema-method">Schema.prototype.method()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">method
-<span class="method-type">&laquo;String|Object&raquo;</span> name</li><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Adds an instance method to documents constructed from Models compiled from this schema.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = kittySchema = <span class="hljs-keyword">new</span> Schema(..);
-
-schema.method(<span class="hljs-string">'meow'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'meeeeeoooooooooooow'</span>);
-})
-
-<span class="hljs-keyword">var</span> Kitty = mongoose.model(<span class="hljs-string">'Kitty'</span>, schema);
-
-<span class="hljs-keyword">var</span> fizz = <span class="hljs-keyword">new</span> Kitty;
-fizz.meow(); <span class="hljs-comment">// meeeeeooooooooooooow</span></code></pre>
-
-<p>If a hash of name/fn pairs is passed as the only argument, each name/fn pair will be added as methods.</p>
-
-<pre><code>schema.method({
-    purr: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{}
-  , scratch: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{}
-});
-
-<span class="hljs-comment">// later</span>
-fizz.purr();
-fizz.scratch();</code></pre>
-
-<p>NOTE: <code>Schema.method()</code> adds instance methods to the <code>Schema.methods</code> object. You can also add instance methods directly to the <code>Schema.methods</code> object as seen in the <a href="./guide.html#methods">guide</a></p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-obj"><a href="#schema_Schema-obj">Schema.prototype.obj</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>The original object passed to the schema constructor</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ a: <span class="hljs-built_in">String</span> }).add({ b: <span class="hljs-built_in">String</span> });
-schema.obj; <span class="hljs-comment">// { a: String }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-path"><a href="#schema_Schema-path">Schema.prototype.path()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">constructor
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Gets/sets schema paths.</p>
-
-<p>Sets a path (if arity 2) Gets a path (if arity 1)</p>
-
-<h4>Example</h4>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>) <span class="hljs-comment">// returns a SchemaType</span>
-schema.path(<span class="hljs-string">'name'</span>, <span class="hljs-built_in">Number</span>) <span class="hljs-comment">// changes the schemaType of `name` to Number</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-pathType"><a href="#schema_Schema-pathType">Schema.prototype.pathType()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>Returns the pathType of <code>path</code> for this schema.</p>
-
-<p>Given a path, returns whether it is a real, virtual, nested, or ad-hoc/undefined path.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, nested: { foo: <span class="hljs-built_in">String</span> } });
-s.virtual(<span class="hljs-string">'foo'</span>).get(() =&gt; <span class="hljs-number">42</span>);
-s.pathType(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// "real"</span>
-s.pathType(<span class="hljs-string">'nested'</span>); <span class="hljs-comment">// "nested"</span>
-s.pathType(<span class="hljs-string">'foo'</span>); <span class="hljs-comment">// "virtual"</span>
-s.pathType(<span class="hljs-string">'fail'</span>); <span class="hljs-comment">// "adhocOrUndefined"</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-plugin"><a href="#schema_Schema-plugin">Schema.prototype.plugin()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">plugin
-<span class="method-type">&laquo;Function&raquo;</span> callback</li><li class="param">[opts]
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><div><p>Registers a plugin for this schema.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-s.plugin(schema =&gt; <span class="hljs-built_in">console</span>.log(schema.path(<span class="hljs-string">'name'</span>).path));
-mongoose.model(<span class="hljs-string">'Test'</span>, schema); <span class="hljs-comment">// Prints 'name'</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-post"><a href="#schema_Schema-post">Schema.prototype.post()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">The
-<span class="method-type">&laquo;String|RegExp&raquo;</span> method name or regular expression to match method name</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.document]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on document middleware.</li></ul><ul style="margin-top: 0.5em"><li>[options.query]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on query middleware.</li></ul><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> callback</li></ul><div><p>Defines a post hook for the document</p>
-
-<pre><code>var schema = new Schema(..);
-schema.post('save', function (doc) {
-  console.log('this fired after a document was saved');
-});
-
-schema.post('find', function(docs) {
-  console.log('this fired after you ran a find query');
-});
-
-schema.post(/Many$/, function(res) {
-  console.log('this fired after you ran `updateMany()` or `deleteMany()`);
-});
-
-var Model = mongoose.model('Model', schema);
-
-var m = new Model(..);
-m.save(function(err) {
-  console.log('this fires after the `post` hook');
-});
-
-m.find(function(err, docs) {
-  console.log('this fires after the post find hook');
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-pre"><a href="#schema_Schema-pre">Schema.prototype.pre()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">The
-<span class="method-type">&laquo;String|RegExp&raquo;</span> method name or regular expression to match method name</li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.document]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on document middleware.</li></ul><ul style="margin-top: 0.5em"><li>[options.query]
-<span class="method-type">&laquo;Boolean&raquo;</span> If <code>name</code> is a hook for both document and query middleware, set to <code>true</code> to run on query middleware.</li></ul><li class="param">callback
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Defines a pre hook for the document.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">var</span> toySchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, created: <span class="hljs-built_in">Date</span> });
-
-toySchema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">if</span> (!<span class="hljs-keyword">this</span>.created) <span class="hljs-keyword">this</span>.created = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>;
-  next();
-});
-
-toySchema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">if</span> (<span class="hljs-keyword">this</span>.name !== <span class="hljs-string">'Woody'</span>) <span class="hljs-keyword">this</span>.name = <span class="hljs-string">'Woody'</span>;
-  next();
-});
-
-<span class="hljs-comment">// Equivalent to calling `pre()` on `find`, `findOne`, `findOneAndUpdate`.</span>
-toySchema.pre(<span class="hljs-regexp">/^find/</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>.getFilter());
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-queue"><a href="#schema_Schema-queue">Schema.prototype.queue()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> name of the document method to call later</li><li class="param">args
-<span class="method-type">&laquo;Array&raquo;</span> arguments to pass to the method</li></ul><div><p>Adds a method call to the queue.</p>
-
-<h4>Example:</h4>
-
-<pre><code>schema.methods.print = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>); };
-schema.queue(<span class="hljs-string">'print'</span>, []); <span class="hljs-comment">// Print the doc every one is instantiated</span>
-
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">new</span> Model({ name: <span class="hljs-string">'test'</span> }); <span class="hljs-comment">// Prints '{"_id": ..., "name": "test" }'</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-remove"><a href="#schema_Schema-remove">Schema.prototype.remove()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String|Array&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Schema&raquo;</span> the Schema instance</li></ul><div><p>Removes the given <code>path</code> (or [<code>paths</code>]).</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, age: <span class="hljs-built_in">Number</span> });
-schema.remove(<span class="hljs-string">'name'</span>);
-schema.path(<span class="hljs-string">'name'</span>); <span class="hljs-comment">// Undefined</span>
-schema.path(<span class="hljs-string">'age'</span>); <span class="hljs-comment">// SchemaNumber { ... }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-requiredPaths"><a href="#schema_Schema-requiredPaths">Schema.prototype.requiredPaths()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">invalidate
-<span class="method-type">&laquo;Boolean&raquo;</span> refresh the cache</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Array&raquo;</span> </li></ul><div><p>Returns an Array of path strings that are required by this schema.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> s = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  age: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  notes: <span class="hljs-built_in">String</span>
-});
-s.requiredPaths(); <span class="hljs-comment">// [ 'age', 'name' ]</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-set"><a href="#schema_Schema-set">Schema.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> option name</li><li class="param">[value]
-<span class="method-type">&laquo;Object&raquo;</span> if not passed, the current option value is returned</li></ul><div><p>Sets/gets a schema option.</p>
-
-<h4>Example</h4>
-
-<pre><code>schema.set(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// 'true' by default</span>
-schema.set(<span class="hljs-string">'strict'</span>, <span class="hljs-literal">false</span>); <span class="hljs-comment">// Sets 'strict' to false</span>
-schema.set(<span class="hljs-string">'strict'</span>); <span class="hljs-comment">// 'false'</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-static"><a href="#schema_Schema-static">Schema.prototype.static()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String|Object&raquo;</span> </li><li class="param">[fn]
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Adds static "class" methods to Models compiled from this schema.</p>
-
-<h4>Example</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema(..);
-<span class="hljs-comment">// Equivalent to `schema.statics.findByName = function(name) {}`;</span>
-schema.static(<span class="hljs-string">'findByName'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">name</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.find({ name: name });
-});
-
-<span class="hljs-keyword">const</span> Drink = mongoose.model(<span class="hljs-string">'Drink'</span>, schema);
-<span class="hljs-keyword">await</span> Drink.findByName(<span class="hljs-string">'LaCroix'</span>);</code></pre>
-
-<p>If a hash of name/fn pairs is passed as the only argument, each name/fn pair will be added as statics.</p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-virtual"><a href="#schema_Schema-virtual">Schema.prototype.virtual()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.ref]
-<span class="method-type">&laquo;String|Model&raquo;</span> model name or model instance. Marks this as a <a href="populate.html#populate-virtuals">populate virtual</a>.</li></ul><ul style="margin-top: 0.5em"><li>[options.localField]
-<span class="method-type">&laquo;String|Function&raquo;</span> Required for populate virtuals. See <a href="populate.html#populate-virtuals">populate virtual docs</a> for more information.</li></ul><ul style="margin-top: 0.5em"><li>[options.foreignField]
-<span class="method-type">&laquo;String|Function&raquo;</span> Required for populate virtuals. See <a href="populate.html#populate-virtuals">populate virtual docs</a> for more information.</li></ul><ul style="margin-top: 0.5em"><li>[options.justOne=false]
-<span class="method-type">&laquo;Boolean|Function&raquo;</span> Only works with populate virtuals. If truthy, will be a single doc or <code>null</code>. Otherwise, the populate virtual will be an array.</li></ul><ul style="margin-top: 0.5em"><li>[options.count=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> Only works with populate virtuals. If truthy, this populate virtual will contain the number of documents rather than the documents themselves when you <code>populate()</code>.</li></ul></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> </li></ul><div><p>Creates a virtual type with the given name.</p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema-virtualpath"><a href="#schema_Schema-virtualpath">Schema.prototype.virtualpath()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> </li></ul><div><p>Returns the virtual type with the given <code>name</code>.</p>  </div><hr class="separate-api-elements"><h3 id="schema_Schema.reserved"><a href="#schema_Schema.reserved">Schema.reserved</a></h3><h5>Type:</h5><ul><li><span class="method-type">&laquo;property&raquo;</span></li></ul><div><p>Reserved document keys.</p>
-
-<p>Keys in this object are names that are rejected in schema declarations because they conflict with Mongoose functionality. If you create a schema using <code>new Schema()</code> with one of these property names, Mongoose will throw an error.</p>
-
-<ul>
-<li>prototype</li>
-<li>emit</li>
-<li>on</li>
-<li>once</li>
-<li>listeners</li>
-<li>removeListener</li>
-<li>collection</li>
-<li>db</li>
-<li>errors</li>
-<li>init</li>
-<li>isModified</li>
-<li>isNew</li>
-<li>get</li>
-<li>modelName</li>
-<li>save</li>
-<li>schema</li>
-<li>toObject</li>
-<li>validate</li>
-<li>remove</li>
-<li>populated</li>
-<li>_pres</li>
-<li>_posts</li>
-</ul>
-
-<p><em>NOTE:</em> Use of these terms as method names is permitted, but play at your own risk, as they may be existing mongoose document methods you are stomping on.</p>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema(..);
- schema.methods.init = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{} <span class="hljs-comment">// potentially breaking</span></code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/schematype.html b/docs/api/schematype.html
deleted file mode 100644
index 28ba7f48156..00000000000
--- a/docs/api/schematype.html
+++ /dev/null
@@ -1,498 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Schematype</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title" style="font-weight: bold"><a href="schematype.html">Schematype</a></div><ul class="nav-item-sub"><li><a href="#schematype_SchemaType">SchemaType()</a></li><li><a href="#schematype_SchemaType-cast">SchemaType.cast()</a></li><li><a href="#schematype_SchemaType-checkRequired">SchemaType.checkRequired()</a></li><li><a href="#schematype_SchemaType-get">SchemaType.get()</a></li><li><a href="#schematype_SchemaType-default">SchemaType.prototype.default()</a></li><li><a href="#schematype_SchemaType-get">SchemaType.prototype.get()</a></li><li><a href="#schematype_SchemaType-immutable">SchemaType.prototype.immutable()</a></li><li><a href="#schematype_SchemaType-index">SchemaType.prototype.index()</a></li><li><a href="#schematype_SchemaType-ref">SchemaType.prototype.ref()</a></li><li><a href="#schematype_SchemaType-required">SchemaType.prototype.required()</a></li><li><a href="#schematype_SchemaType-select">SchemaType.prototype.select()</a></li><li><a href="#schematype_SchemaType-set">SchemaType.prototype.set()</a></li><li><a href="#schematype_SchemaType-sparse">SchemaType.prototype.sparse()</a></li><li><a href="#schematype_SchemaType-text">SchemaType.prototype.text()</a></li><li><a href="#schematype_SchemaType-unique">SchemaType.prototype.unique()</a></li><li><a href="#schematype_SchemaType-validate">SchemaType.prototype.validate()</a></li></ul></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#schematype_SchemaType">SchemaType()</a></li><li><a href="#schematype_SchemaType-cast">SchemaType.cast()</a></li><li><a href="#schematype_SchemaType-checkRequired">SchemaType.checkRequired()</a></li><li><a href="#schematype_SchemaType-get">SchemaType.get()</a></li><li><a href="#schematype_SchemaType-default">SchemaType.prototype.default()</a></li><li><a href="#schematype_SchemaType-get">SchemaType.prototype.get()</a></li><li><a href="#schematype_SchemaType-immutable">SchemaType.prototype.immutable()</a></li><li><a href="#schematype_SchemaType-index">SchemaType.prototype.index()</a></li><li><a href="#schematype_SchemaType-ref">SchemaType.prototype.ref()</a></li><li><a href="#schematype_SchemaType-required">SchemaType.prototype.required()</a></li><li><a href="#schematype_SchemaType-select">SchemaType.prototype.select()</a></li><li><a href="#schematype_SchemaType-set">SchemaType.prototype.set()</a></li><li><a href="#schematype_SchemaType-sparse">SchemaType.prototype.sparse()</a></li><li><a href="#schematype_SchemaType-text">SchemaType.prototype.text()</a></li><li><a href="#schematype_SchemaType-unique">SchemaType.prototype.unique()</a></li><li><a href="#schematype_SchemaType-validate">SchemaType.prototype.validate()</a></li></ul><hr class="separate-api-elements"><h3 id="schematype_SchemaType"><a href="#schematype_SchemaType">SchemaType()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">path
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">[options]
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">[instance]
-<span class="method-type">&laquo;String&raquo;</span> </li></ul><div><p>SchemaType constructor. Do <strong>not</strong> instantiate <code>SchemaType</code> directly. Mongoose converts your schema paths into SchemaTypes automatically.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>) <span class="hljs-keyword">instanceof</span> SchemaType; <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-cast"><a href="#schematype_SchemaType-cast">SchemaType.cast()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">caster
-<span class="method-type">&laquo;Function|false&raquo;</span> Function that casts arbitrary values to this type, or throws an error if casting failed</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Get/set the function used to cast arbitrary values to this type.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Disallow `null` for numbers, and don't try to cast any values to</span>
-<span class="hljs-comment">// numbers, so even strings like '123' will cause a CastError.</span>
-mongoose.Number.cast(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-  assert.ok(v === <span class="hljs-literal">undefined</span> || <span class="hljs-keyword">typeof</span> v === <span class="hljs-string">'number'</span>);
-  <span class="hljs-keyword">return</span> v;
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-checkRequired"><a href="#schematype_SchemaType-checkRequired">SchemaType.checkRequired()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;Function&raquo;</span> </li></ul><div><p>Override the function the required validator uses to check whether a value passes the <code>required</code> check. Override this on the individual SchemaType.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Use this to allow empty strings to pass the `required` validator</span>
-mongoose.Schema.Types.String.checkRequired(v =&gt; <span class="hljs-keyword">typeof</span> v === <span class="hljs-string">'string'</span>);</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-get"><a href="#schematype_SchemaType-get">SchemaType.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">getter
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;this&raquo;</span> </li></ul><div><p>Attaches a getter for all instances of this schema type.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Make all numbers round down</span>
-mongoose.Number.get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-built_in">Math</span>.floor(v); });</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-default"><a href="#schematype_SchemaType-default">SchemaType.prototype.default()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Function|any&raquo;</span> the default value</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;defaultValue&raquo;</span> </li></ul><div><p>Sets a default value for this SchemaType.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ n: { type: <span class="hljs-built_in">Number</span>, <span class="hljs-keyword">default</span>: <span class="hljs-number">10</span> })
-<span class="hljs-keyword">var</span> M = db.model(<span class="hljs-string">'M'</span>, schema)
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M;
-<span class="hljs-built_in">console</span>.log(m.n) <span class="hljs-comment">// 10</span></code></pre>
-
-<p>Defaults can be either <code>functions</code> which return the value to use as the default or the literal value itself. Either way, the value will be cast based on its schema type before being set during document creation.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// values are cast:</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ aNumber: { type: <span class="hljs-built_in">Number</span>, <span class="hljs-keyword">default</span>: <span class="hljs-number">4.815162342</span> }})
-<span class="hljs-keyword">var</span> M = db.model(<span class="hljs-string">'M'</span>, schema)
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M;
-<span class="hljs-built_in">console</span>.log(m.aNumber) <span class="hljs-comment">// 4.815162342</span>
-
-<span class="hljs-comment">// default unique objects for Mixed types:</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ mixed: Schema.Types.Mixed });
-schema.path(<span class="hljs-string">'mixed'</span>).default(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> {};
-});
-
-<span class="hljs-comment">// if we don't use a function to return object literals for Mixed defaults,</span>
-<span class="hljs-comment">// each document will receive a reference to the same object literal creating</span>
-<span class="hljs-comment">// a "shared" object instance:</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ mixed: Schema.Types.Mixed });
-schema.path(<span class="hljs-string">'mixed'</span>).default({});
-<span class="hljs-keyword">var</span> M = db.model(<span class="hljs-string">'M'</span>, schema);
-<span class="hljs-keyword">var</span> m1 = <span class="hljs-keyword">new</span> M;
-m1.mixed.added = <span class="hljs-number">1</span>;
-<span class="hljs-built_in">console</span>.log(m1.mixed); <span class="hljs-comment">// { added: 1 }</span>
-<span class="hljs-keyword">var</span> m2 = <span class="hljs-keyword">new</span> M;
-<span class="hljs-built_in">console</span>.log(m2.mixed); <span class="hljs-comment">// { added: 1 }</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-get"><a href="#schematype_SchemaType-get">SchemaType.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds a getter to this schematype.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">dob</span> (<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">if</span> (!val) <span class="hljs-keyword">return</span> val;
-  <span class="hljs-keyword">return</span> (val.getMonth() + <span class="hljs-number">1</span>) + <span class="hljs-string">"/"</span> + val.getDate() + <span class="hljs-string">"/"</span> + val.getFullYear();
-}
-
-<span class="hljs-comment">// defining within the schema</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: { type: <span class="hljs-built_in">Date</span>, get: dob })
-
-<span class="hljs-comment">// or by retreiving its SchemaType</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: <span class="hljs-built_in">Date</span> })
-s.path(<span class="hljs-string">'born'</span>).get(dob)</code></pre>
-
-<p>Getters allow you to transform the representation of the data as it travels from the raw mongodb document to the value that you see.</p>
-
-<p>Suppose you are storing credit card numbers and you want to hide everything except the last 4 digits to the mongoose user. You can do so by defining a getter in the following way:</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">obfuscate</span> (<span class="hljs-params">cc</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-string">'****-****-****-'</span> + cc.slice(cc.length<span class="hljs-number">-4</span>, cc.length);
-}
-
-<span class="hljs-keyword">var</span> AccountSchema = <span class="hljs-keyword">new</span> Schema({
-  creditCardNumber: { type: <span class="hljs-built_in">String</span>, get: obfuscate }
-});
-
-<span class="hljs-keyword">var</span> Account = db.model(<span class="hljs-string">'Account'</span>, AccountSchema);
-
-Account.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, found</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(found.creditCardNumber); <span class="hljs-comment">// '****-****-****-1234'</span>
-});</code></pre>
-
-<p>Getters are also passed a second argument, the schematype on which the getter was defined. This allows for tailored behavior based on options passed in the schema.</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">inspector</span> (<span class="hljs-params">val, schematype</span>) </span>{
-  <span class="hljs-keyword">if</span> (schematype.options.required) {
-    <span class="hljs-keyword">return</span> schematype.path + <span class="hljs-string">' is required'</span>;
-  } <span class="hljs-keyword">else</span> {
-    <span class="hljs-keyword">return</span> schematype.path + <span class="hljs-string">' is not'</span>;
-  }
-}
-
-<span class="hljs-keyword">var</span> VirusSchema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span>, get: inspector },
-  taxonomy: { type: <span class="hljs-built_in">String</span>, get: inspector }
-})
-
-<span class="hljs-keyword">var</span> Virus = db.model(<span class="hljs-string">'Virus'</span>, VirusSchema);
-
-Virus.findById(id, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, virus</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(virus.name);     <span class="hljs-comment">// name is required</span>
-  <span class="hljs-built_in">console</span>.log(virus.taxonomy); <span class="hljs-comment">// taxonomy is not</span>
-})</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-immutable"><a href="#schematype_SchemaType-immutable">SchemaType.prototype.immutable()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Defines this path as immutable. Mongoose prevents you from changing immutable paths unless the parent document has <a href="/docs/api.html#document_Document-isNew"><code>isNew: true</code></a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, immutable: <span class="hljs-literal">true</span> },
-  age: <span class="hljs-built_in">Number</span>
-});
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">await</span> Model.create({ name: <span class="hljs-string">'test'</span> });
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Model.findOne();
-
-doc.isNew; <span class="hljs-comment">// false</span>
-doc.name = <span class="hljs-string">'new name'</span>;
-doc.name; <span class="hljs-comment">// 'test', because `name` is immutable</span></code></pre>
-
-<p>Mongoose also prevents changing immutable properties using <code>updateOne()</code> and <code>updateMany()</code> based on <a href="/docs/guide.html#strict">strict mode</a>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-comment">// Mongoose will strip out the `name` update, because `name` is immutable</span>
-Model.updateOne({}, { $set: { name: <span class="hljs-string">'test2'</span> }, $inc: { age: <span class="hljs-number">1</span> } });
-
-<span class="hljs-comment">// If `strict` is set to 'throw', Mongoose will throw an error if you</span>
-<span class="hljs-comment">// update `name`</span>
-<span class="hljs-keyword">const</span> err = <span class="hljs-keyword">await</span> Model.updateOne({}, { name: <span class="hljs-string">'test2'</span> }, { strict: <span class="hljs-string">'throw'</span> }).
-  then(() =&gt; <span class="hljs-literal">null</span>, err =&amp;gt; err);
-err.name; <span class="hljs-comment">// StrictModeError</span>
-
-<span class="hljs-comment">// If `strict` is `false`, Mongoose allows updating `name` even though</span>
-<span class="hljs-comment">// the property is immutable.</span>
-Model.updateOne({}, { name: <span class="hljs-string">'test2'</span> }, { strict: <span class="hljs-literal">false</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-index"><a href="#schematype_SchemaType-index">SchemaType.prototype.index()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object|Boolean|String&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares the index options for this schematype.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, index: <span class="hljs-literal">true</span> })
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ loc: { type: [<span class="hljs-built_in">Number</span>], index: <span class="hljs-string">'hashed'</span> })
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ loc: { type: [<span class="hljs-built_in">Number</span>], index: <span class="hljs-string">'2d'</span>, sparse: <span class="hljs-literal">true</span> })
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ loc: { type: [<span class="hljs-built_in">Number</span>], index: { type: <span class="hljs-string">'2dsphere'</span>, sparse: <span class="hljs-literal">true</span> }})
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ date: { type: <span class="hljs-built_in">Date</span>, index: { unique: <span class="hljs-literal">true</span>, expires: <span class="hljs-string">'1d'</span> }})
-Schema.path(<span class="hljs-string">'my.path'</span>).index(<span class="hljs-literal">true</span>);
-Schema.path(<span class="hljs-string">'my.date'</span>).index({ expires: <span class="hljs-number">60</span> });
-Schema.path(<span class="hljs-string">'my.path'</span>).index({ unique: <span class="hljs-literal">true</span>, sparse: <span class="hljs-literal">true</span> });</code></pre>
-
-<h4>NOTE:</h4>
-
-<p><em>Indexes are created <a href="https://docs.mongodb.com/manual/core/index-creation/#index-creation-background">in the background</a> by default. If <code>background</code> is set to <code>false</code>, MongoDB will not execute any read/write operations you send until the index build. Specify <code>background: false</code> to override Mongoose's default.</em></p>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-ref"><a href="#schematype_SchemaType-ref">SchemaType.prototype.ref()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">ref
-<span class="method-type">&laquo;String|Model|Function&raquo;</span> either a model name, a <a href="https://mongoosejs.com/docs/models.html">Model</a>, or a function that returns a model name or model.</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Set the model that this path refers to. This is the option that <a href="https://mongoosejs.com/docs/populate.html">populate</a> looks at to determine the foreign collection it should query.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">const</span> postSchema = <span class="hljs-keyword">new</span> Schema({ user: mongoose.ObjectId });
-postSchema.path(<span class="hljs-string">'user'</span>).ref(<span class="hljs-string">'User'</span>); <span class="hljs-comment">// By model name</span>
-postSchema.path(<span class="hljs-string">'user'</span>).ref(User); <span class="hljs-comment">// Can pass the model as well</span>
-
-<span class="hljs-comment">// Or you can just declare the `ref` inline in your schema</span>
-<span class="hljs-keyword">const</span> postSchema2 = <span class="hljs-keyword">new</span> Schema({
-  user: { type: mongoose.ObjectId, ref: User }
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-required"><a href="#schematype_SchemaType-required">SchemaType.prototype.required()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">required
-<span class="method-type">&laquo;Boolean|Function|Object&raquo;</span> enable/disable the validator, or function that returns required boolean, or options object</li><ul style="margin-top: 0.5em"><li>[options.isRequired]
-<span class="method-type">&laquo;Boolean|Function&raquo;</span> enable/disable the validator, or function that returns required boolean</li></ul><ul style="margin-top: 0.5em"><li>[options.ErrorConstructor]
-<span class="method-type">&laquo;Function&raquo;</span> custom error constructor. The constructor receives 1 parameter, an object containing the validator properties.</li></ul><li class="param">[message]
-<span class="method-type">&laquo;String&raquo;</span> optional custom error message</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds a required validator to this SchemaType. The validator gets added to the front of this SchemaType's validators array using <code>unshift()</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: { type: <span class="hljs-built_in">Date</span>, required: <span class="hljs-literal">true</span> })
-
-<span class="hljs-comment">// or with custom error message</span>
-
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ born: { type: <span class="hljs-built_in">Date</span>, required: <span class="hljs-string">'{PATH} is required!'</span> })
-
-<span class="hljs-comment">// or with a function</span>
-
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({
-  userId: ObjectId,
-  username: {
-    type: <span class="hljs-built_in">String</span>,
-    required: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.userId != <span class="hljs-literal">null</span>; }
-  }
-})
-
-<span class="hljs-comment">// or with a function and a custom message</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({
-  userId: ObjectId,
-  username: {
-    type: <span class="hljs-built_in">String</span>,
-    required: [
-      <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.userId != <span class="hljs-literal">null</span>; },
-      <span class="hljs-string">'username is required if id is specified'</span>
-    ]
-  }
-})
-
-<span class="hljs-comment">// or through the path API</span>
-
-Schema.path(<span class="hljs-string">'name'</span>).required(<span class="hljs-literal">true</span>);
-
-<span class="hljs-comment">// with custom error messaging</span>
-
-Schema.path(<span class="hljs-string">'name'</span>).required(<span class="hljs-literal">true</span>, <span class="hljs-string">'grrr :( '</span>);
-
-<span class="hljs-comment">// or make a path conditionally required based on a function</span>
-<span class="hljs-keyword">var</span> isOver18 = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.age &gt;= <span class="hljs-number">18</span>; };
-Schema.path(<span class="hljs-string">'voterRegistrationId'</span>).required(isOver18);</code></pre>
-
-<p>The required validator uses the SchemaType's <code>checkRequired</code> function to determine whether a given value satisfies the required validator. By default, a value satisfies the required validator if <code>val != null</code> (that is, if the value is not null nor undefined). However, most built-in mongoose schema types override the default <code>checkRequired</code> function:</p>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-select"><a href="#schematype_SchemaType-select">SchemaType.prototype.select()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">val
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Sets default <code>select()</code> behavior for this path.</p>
-
-<p>Set to <code>true</code> if this path should always be included in the results, <code>false</code> if it should be excluded by default. This setting can be overridden at the query level.</p>
-
-<h4>Example:</h4>
-
-<pre><code>T = db.model(<span class="hljs-string">'T'</span>, <span class="hljs-keyword">new</span> Schema({ x: { type: <span class="hljs-built_in">String</span>, select: <span class="hljs-literal">true</span> }}));
-T.find(..); <span class="hljs-comment">// field x will always be selected ..</span>
-<span class="hljs-comment">// .. unless overridden;</span>
-T.find().select(<span class="hljs-string">'-x'</span>).exec(callback);</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-set"><a href="#schematype_SchemaType-set">SchemaType.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">fn
-<span class="method-type">&laquo;Function&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds a setter to this schematype.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">capitalize</span> (<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">if</span> (<span class="hljs-keyword">typeof</span> val !== <span class="hljs-string">'string'</span>) val = <span class="hljs-string">''</span>;
-  <span class="hljs-keyword">return</span> val.charAt(<span class="hljs-number">0</span>).toUpperCase() + val.substring(<span class="hljs-number">1</span>);
-}
-
-<span class="hljs-comment">// defining within the schema</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, set: capitalize }});
-
-<span class="hljs-comment">// or with the SchemaType</span>
-<span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> })
-s.path(<span class="hljs-string">'name'</span>).set(capitalize);</code></pre>
-
-<p>Setters allow you to transform the data before it gets to the raw mongodb document or query.</p>
-
-<p>Suppose you are implementing user registration for a website. Users provide an email and password, which gets saved to mongodb. The email is a string that you will want to normalize to lower case, in order to avoid one email having more than one account -- e.g., otherwise, <a href='mailto:avenue@q.com'>avenue@q.com</a> can be registered for 2 accounts via <a href='mailto:avenue@q.com'>avenue@q.com</a> and <a href='mailto:AvEnUe@Q.CoM'>AvEnUe@Q.CoM</a>.</p>
-
-<p>You can set up email lower case normalization easily via a Mongoose setter.</p>
-
-<pre><code>function toLower(v) {
-  return v.toLowerCase();
-}
-
-var UserSchema = new Schema({
-  email: { type: String, set: toLower }
-});
-
-var User = db.model('User', UserSchema);
-
-var user = new User({email: '<a href='mailto:AVENUE@Q.COM'>AVENUE@Q.COM</a>'});
-console.log(user.email); // '<a href='mailto:avenue@q.com'>avenue@q.com</a>'
-
-// or
-var user = new User();
-user.email = '<a href='mailto:Avenue@Q.com'>Avenue@Q.com</a>';
-console.log(user.email); // '<a href='mailto:avenue@q.com'>avenue@q.com</a>'
-User.updateOne({ _id: _id }, { $set: { email: '<a href='mailto:AVENUE@Q.COM'>AVENUE@Q.COM</a>' } }); // update to '<a href='mailto:avenue@q.com'>avenue@q.com</a>'
-</code></pre>
-
-<p>As you can see above, setters allow you to transform the data before it stored in MongoDB, or before executing a query.</p>
-
-<p><em>NOTE: we could have also just used the built-in <code>lowercase: true</code> SchemaType option instead of defining our own function.</em></p>
-
-<pre><code><span class="hljs-keyword">new</span> Schema({ email: { type: <span class="hljs-built_in">String</span>, lowercase: <span class="hljs-literal">true</span> }})</code></pre>
-
-<p>Setters are also passed a second argument, the schematype on which the setter was defined. This allows for tailored behavior based on options passed in the schema.</p>
-
-<pre><code><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">inspector</span> (<span class="hljs-params">val, schematype</span>) </span>{
-  <span class="hljs-keyword">if</span> (schematype.options.required) {
-    <span class="hljs-keyword">return</span> schematype.path + <span class="hljs-string">' is required'</span>;
-  } <span class="hljs-keyword">else</span> {
-    <span class="hljs-keyword">return</span> val;
-  }
-}
-
-<span class="hljs-keyword">var</span> VirusSchema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span>, set: inspector },
-  taxonomy: { type: <span class="hljs-built_in">String</span>, set: inspector }
-})
-
-<span class="hljs-keyword">var</span> Virus = db.model(<span class="hljs-string">'Virus'</span>, VirusSchema);
-<span class="hljs-keyword">var</span> v = <span class="hljs-keyword">new</span> Virus({ name: <span class="hljs-string">'Parvoviridae'</span>, taxonomy: <span class="hljs-string">'Parvovirinae'</span> });
-
-<span class="hljs-built_in">console</span>.log(v.name);     <span class="hljs-comment">// name is required</span>
-<span class="hljs-built_in">console</span>.log(v.taxonomy); <span class="hljs-comment">// Parvovirinae</span></code></pre>
-
-<p>You can also use setters to modify other properties on the document. If you're setting a property <code>name</code> on a document, the setter will run with <code>this</code> as the document. Be careful, in mongoose 5 setters will also run when querying by <code>name</code> with <code>this</code> as the query.</p>
-
-<div class="highlight"><pre lang="javascript">const nameSchema = new Schema({ name: String, keywords: [String] });
-nameSchema.path('name').set(function(v) {
-  // Need to check if `this` is a document, because in mongoose 5
-  // setters will also run on queries, in which case `this` will be a
-  // mongoose query object.
-  if (this instanceof Document && v != null) {
-    this.keywords = v.split(' ');
-  }
-  return v;
-});
-</pre></div>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-sparse"><a href="#schematype_SchemaType-sparse">SchemaType.prototype.sparse()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares a sparse index.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, sparse: <span class="hljs-literal">true</span> } });
-Schema.path(<span class="hljs-string">'name'</span>).index({ sparse: <span class="hljs-literal">true</span> });</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-text"><a href="#schematype_SchemaType-text">SchemaType.prototype.text()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares a full text index.</p>
-
-<h3>Example:</h3>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({name : {type: <span class="hljs-built_in">String</span>, text : <span class="hljs-literal">true</span> })
- Schema.path(<span class="hljs-string">'name'</span>).index({text : <span class="hljs-literal">true</span>});</code></pre>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-unique"><a href="#schematype_SchemaType-unique">SchemaType.prototype.unique()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">bool
-<span class="method-type">&laquo;Boolean&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Declares an unique index.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> s = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, unique: <span class="hljs-literal">true</span> }});
-Schema.path(<span class="hljs-string">'name'</span>).index({ unique: <span class="hljs-literal">true</span> });</code></pre>
-
-<p><em>NOTE: violating the constraint returns an <code>E11000</code> error from MongoDB when saving, not a Mongoose validation error.</em></p>  </div><hr class="separate-api-elements"><h3 id="schematype_SchemaType-validate"><a href="#schematype_SchemaType-validate">SchemaType.prototype.validate()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">obj
-<span class="method-type">&laquo;RegExp|Function|Object&raquo;</span> validator function, or hash describing options</li><ul style="margin-top: 0.5em"><li>[obj.validator]
-<span class="method-type">&laquo;Function&raquo;</span> validator function. If the validator function returns <code>undefined</code> or a truthy value, validation succeeds. If it returns falsy (except <code>undefined</code>) or throws an error, validation fails.</li></ul><ul style="margin-top: 0.5em"><li>[obj.message]
-<span class="method-type">&laquo;String|Function&raquo;</span> optional error message. If function, should return the error message as a string</li></ul><ul style="margin-top: 0.5em"><li>[obj.propsParameter=false]
-<span class="method-type">&laquo;Boolean&raquo;</span> If true, Mongoose will pass the validator properties object (with the <code>validator</code> function, <code>message</code>, etc.) as the 2nd arg to the validator function. This is disabled by default because many validators <a href="https://github.com/chriso/validator.js#validators">rely on positional args</a>, so turning this on may cause unpredictable behavior in external validators.</li></ul><li class="param">[errorMsg]
-<span class="method-type">&laquo;String|Function&raquo;</span> optional error message. If function, should return the error message as a string</li><li class="param">[type]
-<span class="method-type">&laquo;String&raquo;</span> optional validator type</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span> this</li></ul><div><p>Adds validator(s) for this document path.</p>
-
-<p>Validators always receive the value to validate as their first argument and must return <code>Boolean</code>. Returning <code>false</code> or throwing an error means validation failed.</p>
-
-<p>The error message argument is optional. If not passed, the <a href="#error_messages_MongooseError-messages">default generic error message template</a> will be used.</p>
-
-<h4>Examples:</h4>
-
-<pre><code><span class="hljs-comment">// make sure every value is equal to "something"</span>
-<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">validator</span> (<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">return</span> val == <span class="hljs-string">'something'</span>;
-}
-<span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, validate: validator }});
-
-<span class="hljs-comment">// with a custom error message</span>
-
-<span class="hljs-keyword">var</span> custom = [validator, <span class="hljs-string">'Uh oh, {PATH} does not equal "something".'</span>]
-<span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, validate: custom }});
-
-<span class="hljs-comment">// adding many validators at a time</span>
-
-<span class="hljs-keyword">var</span> many = [
-    { validator: validator, msg: <span class="hljs-string">'uh oh'</span> }
-  , { validator: anotherValidator, msg: <span class="hljs-string">'failed'</span> }
-]
-<span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, validate: many }});
-
-<span class="hljs-comment">// or utilizing SchemaType methods directly:</span>
-
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-string">'string'</span> });
-schema.path(<span class="hljs-string">'name'</span>).validate(validator, <span class="hljs-string">'validation of `{PATH}` failed with value `{VALUE}`'</span>);</code></pre>
-
-<h4>Error message templates:</h4>
-
-<p>From the examples above, you may have noticed that error messages support basic templating. There are a few other template keywords besides <code>{PATH}</code> and <code>{VALUE}</code> too. To find out more, details are available <a href="#error_messages_MongooseError.messages">here</a>.</p>
-
-<p>If Mongoose's built-in error message templating isn't enough, Mongoose supports setting the <code>message</code> property to a function.</p>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>).validate({
-  validator: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> v.length &gt; <span class="hljs-number">5</span>; },
-  <span class="hljs-comment">// `errors['name']` will be "name must have length 5, got 'foo'"</span>
-  message: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">props</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-string">`<span class="hljs-subst">${props.path}</span> must have length 5, got '<span class="hljs-subst">${props.value}</span>'`</span>;
-  }
-});</code></pre>
-
-<p>To bypass Mongoose's error messages and just copy the error message that the validator throws, do this:</p>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>).validate({
-  validator: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Oops!'</span>); },
-  <span class="hljs-comment">// `errors['name']` will be "Oops!"</span>
-  message: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">props</span>) </span>{ <span class="hljs-keyword">return</span> props.reason.message; }
-});</code></pre>
-
-<h4>Asynchronous validation:</h4>
-
-<p>Mongoose supports validators that return a promise. A validator that returns a promise is called an <em>async validator</em>. Async validators run in parallel, and <code>validate()</code> will wait until all async validators have settled.</p>
-
-<pre><code>schema.path(<span class="hljs-string">'name'</span>).validate({
-  validator: <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">value</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Promise</span>(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">resolve, reject</span>) </span>{
-      resolve(<span class="hljs-literal">false</span>); <span class="hljs-comment">// validation failed</span>
-    });
-  }
-});</code></pre>
-
-<p>You might use asynchronous validators to retreive other documents from the database to validate against or to meet other I/O bound validation needs.</p>
-
-<p>Validation occurs <code>pre('save')</code> or whenever you manually execute <a href="#document_Document-validate">document#validate</a>.</p>
-
-<p>If validation fails during <code>pre('save')</code> and no callback was passed to receive the error, an <code>error</code> event will be emitted on your Models associated db <a href="#connection_Connection">connection</a>, passing the validation error object along.</p>
-
-<pre><code><span class="hljs-keyword">var</span> conn = mongoose.createConnection(..);
-conn.on(<span class="hljs-string">'error'</span>, handleError);
-
-<span class="hljs-keyword">var</span> Product = conn.model(<span class="hljs-string">'Product'</span>, yourSchema);
-<span class="hljs-keyword">var</span> dvd = <span class="hljs-keyword">new</span> Product(..);
-dvd.save(); <span class="hljs-comment">// emits error on the `conn` above</span></code></pre>
-
-<p>If you want to handle these errors at the Model level, add an <code>error</code> listener to your Model as shown below.</p>
-
-<pre><code><span class="hljs-comment">// registering an error listener on the Model lets us handle errors more locally</span>
-Product.on(<span class="hljs-string">'error'</span>, handleError);</code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/singlenestedpath.html b/docs/api/singlenestedpath.html
deleted file mode 100644
index c4a874438c6..00000000000
--- a/docs/api/singlenestedpath.html
+++ /dev/null
@@ -1,78 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.6-pre: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.6-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>SingleNestedPath</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title"><a href="virtualtype.html">Virtualtype</a></div></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div><div class="nav-item" id="nav-SingleNestedPath"><div class="nav-item-title" style="font-weight: bold"><a href="singlenestedpath.html">SingleNestedPath</a></div><ul class="nav-item-sub"><li><a href="#singlenestedpath_SingleNestedPath">SingleNestedPath()</a></li><li><a href="#singlenestedpath_SingleNestedPath-discriminator">SingleNestedPath.prototype.discriminator()</a></li></ul></div></div></div><div class="api-content"><ul><li><a href="#singlenestedpath_SingleNestedPath">SingleNestedPath()</a></li><li><a href="#singlenestedpath_SingleNestedPath-discriminator">SingleNestedPath.prototype.discriminator()</a></li></ul><hr class="separate-api-elements"><h3 id="singlenestedpath_SingleNestedPath"><a href="#singlenestedpath_SingleNestedPath">SingleNestedPath()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">schema
-<span class="method-type">&laquo;Schema&raquo;</span> </li><li class="param">key
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li></ul><h5>Inherits:</h5><ul><li><span class="method-type">&laquo;SchemaType&raquo;</span></li></ul><div><p>Single nested subdocument SchemaType constructor.</p>  </div><hr class="separate-api-elements"><h3 id="singlenestedpath_SingleNestedPath-discriminator"><a href="#singlenestedpath_SingleNestedPath-discriminator">SingleNestedPath.prototype.discriminator()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">name
-<span class="method-type">&laquo;String&raquo;</span> </li><li class="param">schema
-<span class="method-type">&laquo;Schema&raquo;</span> fields to add to the schema for instances of this sub-class</li></ul><div><p>Adds a discriminator to this single nested subdocument.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> shapeSchema = Schema({ name: <span class="hljs-built_in">String</span> }, { discriminatorKey: <span class="hljs-string">'kind'</span> });
-<span class="hljs-keyword">const</span> schema = Schema({ shape: shapeSchema });
-
-<span class="hljs-keyword">const</span> singleNestedPath = parentSchema.path(<span class="hljs-string">'child'</span>);
-singleNestedPath.discriminator(<span class="hljs-string">'Circle'</span>, Schema({ radius: <span class="hljs-built_in">Number</span> }));</code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/api/virtualtype.html b/docs/api/virtualtype.html
deleted file mode 100644
index 28e7102cef8..00000000000
--- a/docs/api/virtualtype.html
+++ /dev/null
@@ -1,124 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/api.css"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>.api-nav .nav-item-sub {
-  display: block !important;
-}
-
-.api-content {
-  margin-top: 3em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Virtualtype</h1><div><div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-</div><div class="api-nav"><div class="api-nav-content"><div class="nav-item" id="nav-Mongoose"><div class="nav-item-title"><a href="mongoose.html">Mongoose</a></div></div><div class="nav-item" id="nav-Schema"><div class="nav-item-title"><a href="schema.html">Schema</a></div></div><div class="nav-item" id="nav-Connection"><div class="nav-item-title"><a href="connection.html">Connection</a></div></div><div class="nav-item" id="nav-Document"><div class="nav-item-title"><a href="document.html">Document</a></div></div><div class="nav-item" id="nav-Model"><div class="nav-item-title"><a href="model.html">Model</a></div></div><div class="nav-item" id="nav-Query"><div class="nav-item-title"><a href="query.html">Query</a></div></div><div class="nav-item" id="nav-QueryCursor"><div class="nav-item-title"><a href="querycursor.html">QueryCursor</a></div></div><div class="nav-item" id="nav-Aggregate"><div class="nav-item-title"><a href="aggregate.html">Aggregate</a></div></div><div class="nav-item" id="nav-AggregationCursor"><div class="nav-item-title"><a href="aggregationcursor.html">AggregationCursor</a></div></div><div class="nav-item" id="nav-Schematype"><div class="nav-item-title"><a href="schematype.html">Schematype</a></div></div><div class="nav-item" id="nav-Virtualtype"><div class="nav-item-title" style="font-weight: bold"><a href="virtualtype.html">Virtualtype</a></div><ul class="nav-item-sub"><li><a href="#virtualtype_VirtualType">VirtualType()</a></li><li><a href="#virtualtype_VirtualType-applyGetters">VirtualType.prototype.applyGetters()</a></li><li><a href="#virtualtype_VirtualType-applySetters">VirtualType.prototype.applySetters()</a></li><li><a href="#virtualtype_VirtualType-get">VirtualType.prototype.get()</a></li><li><a href="#virtualtype_VirtualType-set">VirtualType.prototype.set()</a></li></ul></div><div class="nav-item" id="nav-Error"><div class="nav-item-title"><a href="error.html">Error</a></div></div><div class="nav-item" id="nav-Array"><div class="nav-item-title"><a href="array.html">Array</a></div></div></div></div><div class="api-content"><ul><li><a href="#virtualtype_VirtualType">VirtualType()</a></li><li><a href="#virtualtype_VirtualType-applyGetters">VirtualType.prototype.applyGetters()</a></li><li><a href="#virtualtype_VirtualType-applySetters">VirtualType.prototype.applySetters()</a></li><li><a href="#virtualtype_VirtualType-get">VirtualType.prototype.get()</a></li><li><a href="#virtualtype_VirtualType-set">VirtualType.prototype.set()</a></li></ul><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType"><a href="#virtualtype_VirtualType">VirtualType()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">options
-<span class="method-type">&laquo;Object&raquo;</span> </li><ul style="margin-top: 0.5em"><li>[options.ref]
-<span class="method-type">&laquo;string|function&raquo;</span> if <code>ref</code> is not nullish, this becomes a <a href="/docs/populate.html#populate-virtuals">populated virtual</a></li></ul><ul style="margin-top: 0.5em"><li>[options.localField]
-<span class="method-type">&laquo;string|function&raquo;</span> the local field to populate on if this is a populated virtual.</li></ul><ul style="margin-top: 0.5em"><li>[options.foreignField]
-<span class="method-type">&laquo;string|function&raquo;</span> the foreign field to populate on if this is a populated virtual.</li></ul><ul style="margin-top: 0.5em"><li>[options.justOne=false]
-<span class="method-type">&laquo;boolean&raquo;</span> by default, a populated virtual is an array. If you set <code>justOne</code>, the populated virtual will be a single doc or <code>null</code>.</li></ul><ul style="margin-top: 0.5em"><li>[options.getters=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if you set this to <code>true</code>, Mongoose will call any custom getters you defined on this virtual</li></ul><ul style="margin-top: 0.5em"><li>[options.count=false]
-<span class="method-type">&laquo;boolean&raquo;</span> if you set this to <code>true</code>, <code>populate()</code> will set this virtual to the number of populated documents, as opposed to the documents themselves, using <a href="./api.html#query_Query-countDocuments"><code>Query#countDocuments()</code></a></li></ul></ul><div><p>VirtualType constructor</p>
-
-<p>This is what mongoose uses to define virtual attributes via <code>Schema.prototype.virtual</code>.</p>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> fullname = schema.virtual(<span class="hljs-string">'fullname'</span>);
-fullname <span class="hljs-keyword">instanceof</span> mongoose.VirtualType <span class="hljs-comment">// true</span></code></pre>  </div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-applyGetters"><a href="#virtualtype_VirtualType-applyGetters">VirtualType.prototype.applyGetters()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Document&raquo;</span> The document this virtual is attached to</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;any&raquo;</span> the value after applying all getters</li></ul><div><p>Applies getters to <code>value</code>.</p>  </div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-applySetters"><a href="#virtualtype_VirtualType-applySetters">VirtualType.prototype.applySetters()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">value
-<span class="method-type">&laquo;Object&raquo;</span> </li><li class="param">doc
-<span class="method-type">&laquo;Document&raquo;</span> </li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;any&raquo;</span> the value after applying all setters</li></ul><div><p>Applies setters to <code>value</code>.</p>  </div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-get"><a href="#virtualtype_VirtualType-get">VirtualType.prototype.get()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">VirtualType,
-<span class="method-type">&laquo;Function(Any|&raquo;</span> Document)} fn</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> this</li></ul><div><p>Adds a custom getter to this virtual.</p>
-
-<h2>Mongoose calls the getter function with 3 parameters</h2>
-
-<ul>
-<li><code>value</code>: the value returned by the previous getter. If there is only one getter, <code>value</code> will be <code>undefined</code>.</li>
-<li><code>virtual</code>: the virtual object you called <code>.get()</code> on</li>
-<li><code>doc</code>: the document this virtual is attached to. Equivalent to <code>this</code>.</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">var</span> virtual = schema.virtual(<span class="hljs-string">'fullname'</span>);
-virtual.get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value, virtual, doc</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.name.first + <span class="hljs-string">' '</span> + <span class="hljs-keyword">this</span>.name.last;
-});</code></pre>  </div><hr class="separate-api-elements"><h3 id="virtualtype_VirtualType-set"><a href="#virtualtype_VirtualType-set">VirtualType.prototype.set()</a></h3><h5>Parameters</h5><ul class="params"><li class="param">VirtualType,
-<span class="method-type">&laquo;Function(Any|&raquo;</span> Document)} fn</li></ul><h5>Returns:</h5><ul><li><span class="method-type">&laquo;VirtualType&raquo;</span> this</li></ul><div><p>Adds a custom setter to this virtual.</p>
-
-<h2>Mongoose calls the setter function with 3 parameters</h2>
-
-<ul>
-<li><code>value</code>: the value being set</li>
-<li><code>virtual</code>: the virtual object you're calling <code>.set()</code> on</li>
-<li><code>doc</code>: the document this virtual is attached to. Equivalent to <code>this</code>.</li>
-</ul>
-
-<h4>Example:</h4>
-
-<pre><code><span class="hljs-keyword">const</span> virtual = schema.virtual(<span class="hljs-string">'fullname'</span>);
-virtual.set(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value, virtual, doc</span>) </span>{
-  <span class="hljs-keyword">var</span> parts = value.split(<span class="hljs-string">' '</span>);
-  <span class="hljs-keyword">this</span>.name.first = parts[<span class="hljs-number">0</span>];
-  <span class="hljs-keyword">this</span>.name.last = parts[<span class="hljs-number">1</span>];
-});
-
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model();
-<span class="hljs-comment">// Calls the setter with `value = 'Jean-Luc Picard'`</span>
-doc.fullname = <span class="hljs-string">'Jean-Luc Picard'</span>;
-doc.name.first; <span class="hljs-comment">// 'Jean-Luc'</span>
-doc.name.last; <span class="hljs-comment">// 'Picard'</span></code></pre>  </div></div><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});</script></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/browser.html b/docs/browser.html
deleted file mode 100644
index ea0a5b45039..00000000000
--- a/docs/browser.html
+++ /dev/null
@@ -1,140 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Browser Library</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1>Mongoose in the Browser</h1>
-
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Mongoose supports creating schemas and validating documents in the browser.
-Mongoose&#39;s browser library does <strong>not</strong> support saving documents, <a href="http://mongoosejs.com/docs/queries.html">queries</a>,
-<a href="http://mongoosejs.com/docs/populate.html">populate</a>,
-<a href="http://mongoosejs.com/docs/discriminators.html">discriminators</a>,
-or any other Mongoose feature other than schemas and validating documents.</p>
-<p>Use the below syntax to access the Mongoose browser library.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Using `require()`</span>
-<span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose/browser'</span>);
-
-<span class="hljs-comment">// Using ES6 imports</span>
-<span class="hljs-keyword">import</span> mongoose <span class="hljs-keyword">from</span> <span class="hljs-string">'mongoose/browser'</span>;</code></pre>
-<ul class="toc">
-  <li><a href="#usage">Using the Browser Library</a></li>
-  <li><a href="#webpack">Building With Webpack</a></li>
-</ul>
-
-
-<h2 id="usage">Using the Browser Library</h2>
-
-<p>Mongoose&#39;s browser library is very limited. The only use case it supports
-is validating documents as shown below.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">import</span> mongoose <span class="hljs-keyword">from</span> <span class="hljs-string">'mongoose/browser'</span>;
-
-<span class="hljs-comment">// Mongoose's browser library does **not** have models. It only supports</span>
-<span class="hljs-comment">// schemas and documents. The primary use case is validating documents</span>
-<span class="hljs-comment">// against Mongoose schemas.</span>
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> mongoose.Document({}, <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> }
-}));
-<span class="hljs-comment">// Prints an error because `name` is required.</span>
-<span class="hljs-built_in">console</span>.log(doc.validateSync());</code></pre>
-<h2 id="webpack">Building With Webpack</h2>
-
-<p>Mongoose uses <a href="https://www.ecma-international.org/ecma-262/6.0/">ES2015 (also known as ES6)</a>
-syntax, so in order to use Mongoose with older browsers you&#39;ll need to use
-a tool like <a href="https://www.npmjs.com/package/babel-cli">Babel</a>. As of version
-5.x, Mongoose no longer has an officially supported pre-built browser bundle,
-you need to compile the browser library yourself.</p>
-<p>To build Mongoose&#39;s browser library using Webpack, you&#39;ll need to use
-<a href="https://www.npmjs.com/package/babel-loader"><code>babel-loader</code></a>. Because of
-how Webpack loads <code>require()</code> statements, it pulls in a lot of built-in
-Node.js modules. In order to avoid this, you need to use the
-<a href="https://webpack.js.org/configuration/node/"><code>node</code> Webpack config option</a>
-as shown below.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Below is the Webpack config Mongoose uses for testing</span>
-<span class="hljs-keyword">const</span> config = {
-  entry: [<span class="hljs-string">'./test/files/sample.js'</span>],
-  <span class="hljs-built_in">module</span>: {
-    rules: [
-      {
-        test: <span class="hljs-regexp">/\.js$/</span>,
-        include: [
-          <span class="hljs-regexp">/\/mongoose\//i</span>,
-          <span class="hljs-regexp">/\/kareem\//i</span>
-        ],
-        loader: <span class="hljs-string">'babel-loader'</span>,
-        options: {
-          presets: [<span class="hljs-string">'es2015'</span>]
-        }
-      }
-    ]
-  },
-  node: {
-    <span class="hljs-comment">// Replace these Node.js native modules with empty objects, Mongoose's</span>
-    <span class="hljs-comment">// browser library does not use them.</span>
-    <span class="hljs-comment">// See https://webpack.js.org/configuration/node/</span>
-    dns: <span class="hljs-string">'empty'</span>,
-    fs: <span class="hljs-string">'empty'</span>,
-    <span class="hljs-string">'module'</span>: <span class="hljs-string">'empty'</span>,
-    net: <span class="hljs-string">'empty'</span>,
-    tls: <span class="hljs-string">'empty'</span>
-  },
-  target: <span class="hljs-string">'web'</span>,
-  mode: <span class="hljs-string">'production'</span>
-};</code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/compatibility.html b/docs/compatibility.html
deleted file mode 100644
index cdd4d767b52..00000000000
--- a/docs/compatibility.html
+++ /dev/null
@@ -1,88 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: MongoDB Version Compatibility</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="mongodb-server-version-compatibility">MongoDB Server Version Compatibility</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Mongoose relies on the <a href="http://mongodb.github.io/node-mongodb-native/">MongoDB Node.js Driver</a>
-to talk to MongoDB. You can refer to
-<a href="https://docs.mongodb.com/ecosystem/drivers/driver-compatibility-reference/#node-js-driver-compatibility">this table</a>
-for up-to-date information as to which version of the MongoDB driver
-supports which version of MongoDB.</p>
-<p>Below are the <a href="http://semver.org/">semver</a> ranges representing which
-versions of mongoose are compatible with the listed versions of MongoDB
-server.</p>
-<ul>
-<li>MongoDB Server 2.4.x: mongoose <code>^3.8</code> or <code>4.x</code></li>
-<li>MongoDB Server 2.6.x: mongoose <code>^3.8.8</code> or <code>4.x</code></li>
-<li>MongoDB Server 3.0.x: mongoose <code>^3.8.22</code>, <code>4.x</code>, or <code>5.x</code></li>
-<li>MongoDB Server 3.2.x: mongoose <code>^4.3.0</code> or <code>5.x</code></li>
-<li>MongoDB Server 3.4.x: mongoose <code>^4.7.3</code> or <code>5.x</code></li>
-<li>MongoDB Server 3.6.x: mongoose <code>5.x</code></li>
-<li>MongoDB Server 4.0.x: mongoose <code>^5.2.0</code></li>
-</ul>
-<p>Note that Mongoose 5.x dropped support for all versions of MongoDB before
-3.0.0. If you need to use MongoDB 2.6 or older, use Mongoose 4.x.</p>
-<h2 id="further-reading">Further Reading</h2>
-<p>Are you on Mongoose 3.x and looking to migrate to 4.x? Check out
-<a href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoosejs-moving-forward%2Ftable-of-contents"><em>Moving Forward with Mongoose.js</em> on Pluralsight</a>.
-This video course walks you through the new features and backwards breaking
-changes in Mongoose 4, so you can upgrade with confidence.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/connections.html b/docs/connections.html
deleted file mode 100644
index 554169e5bf0..00000000000
--- a/docs/connections.html
+++ /dev/null
@@ -1,319 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Connecting to MongoDB</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2><a href="#connections">Connections</a></h2>
-
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>You can connect to MongoDB with the <code>mongoose.connect()</code> method.</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/myapp'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});</code></pre>
-<p>This is the minimum needed to connect the <code>myapp</code> database running locally
-on the default port (27017). If connecting fails on your machine, try using
-<code>127.0.0.1</code> instead of <code>localhost</code>.</p>
-<p>You can also specify several more parameters in the <code>uri</code>:</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://username:password@host:port/database?options...'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});</code></pre>
-<p>See the <a href="http://docs.mongodb.org/manual/reference/connection-string/">mongodb connection string spec</a> for more detail.</p>
-<ul class="toc">
-  <li><a href="#buffering">Buffering</a></li>
-  <li><a href="#options">Options</a></li>
-  <li><a href="#connection-string-options">Connection String Options</a></li>
-  <li><a href="#connection-events">Connection Events</a></li>
-  <li><a href="#keepAlive">A note about keepAlive</a></li>
-  <li><a href="#replicaset_connections">Replica Set Connections</a></li>
-  <li><a href="#replicaset-hostnames">Replica Set Host Names</a></li>
-  <li><a href="#mongos_connections">Multi-mongos support</a></li>
-  <li><a href="#multiple_connections">Multiple connections</a></li>
-  <li><a href="#connection_pools">Connection Pools</a></li>
-  <li><a href="#v5-changes">Option Changes in v5.x</a></li>
-</ul>
-
-<h3 id="buffering"><a href="#buffering">Operation Buffering</a></h3>
-
-<p>Mongoose lets you start using your models immediately, without waiting for
-mongoose to establish a connection to MongoDB.</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/myapp'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});
-<span class="hljs-keyword">var</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-comment">// Works</span>
-MyModel.findOne(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, result</span>) </span>{ <span class="hljs-comment">/* ... */</span> });</code></pre>
-<p>That&#39;s because mongoose buffers model function calls internally. This
-buffering is convenient, but also a common source of confusion. Mongoose
-will <em>not</em> throw any errors by default if you use a model without
-connecting.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-comment">// Will just hang until mongoose successfully connects</span>
-MyModel.findOne(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, result</span>) </span>{ <span class="hljs-comment">/* ... */</span> });
-
-setTimeout(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/myapp'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});
-}, <span class="hljs-number">60000</span>);</code></pre>
-<p>To disable buffering, turn off the <a href="./guide.html#bufferCommands"><code>bufferCommands</code> option on your schema</a>.
-If you have <code>bufferCommands</code> on and your connection is hanging, try turning
-<code>bufferCommands</code> off to see if you haven&#39;t opened a connection properly.
-You can also disable <code>bufferCommands</code> globally:</p>
-<pre><code class="language-javascript">mongoose.set(<span class="hljs-string">'bufferCommands'</span>, <span class="hljs-literal">false</span>);</code></pre>
-<h3 id="options"><a href="#options">Options</a></h3>
-
-<p>The <code>connect</code> method also accepts an <code>options</code> object which will be passed
-on to the underlying MongoDB driver.</p>
-<pre><code class="language-javascript">mongoose.connect(uri, options);</code></pre>
-<p>A full list of options can be found on the <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect">MongoDB Node.js driver docs for <code>connect()</code></a>.
-Mongoose passes options to the driver without modification, modulo a few
-exceptions that are explained below.</p>
-<ul>
-<li><code>bufferCommands</code>    - This is a mongoose-specific option (not passed to the MongoDB driver) that disables <a href="http://mongoosejs.com/docs/faq.html#callback_never_executes">mongoose&#39;s buffering mechanism</a></li>
-<li><code>user</code>/<code>pass</code>       - The username and password for authentication. These options are mongoose-specific, they are equivalent to the MongoDB driver&#39;s <code>auth.user</code> and <code>auth.password</code> options.</li>
-<li><code>autoIndex</code>         - By default, mongoose will automatically build indexes defined in your schema when it connects. This is great for development, but not ideal for large production deployments, because index builds can cause performance degradation. If you set <code>autoIndex</code> to false, mongoose will not automatically build indexes for <strong>any</strong> model associated with this connection.</li>
-<li><code>dbName</code>            - Specifies which database to connect to and overrides any database specified in the connection string. If you&#39;re using the <code>mongodb+srv</code> syntax to connect to <a href="https://www.mongodb.com/cloud/atlas">MongoDB Atlas</a>, you <a href="https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626">should use <code>dbName</code> to specify the database</a> because you currently cannot in the connection string.</li>
-</ul>
-<p>Below are some of the options that are important for tuning mongoose.</p>
-<ul>
-<li><code>useNewUrlParser</code>   - The underlying MongoDB driver has deprecated their current <a href="https://docs.mongodb.com/manual/reference/connection-string/">connection string</a> parser. Because this is a major change, they added the <code>useNewUrlParser</code> flag to allow users to fall back to the old parser if they find a bug in the new parser. You should set <code>useNewUrlParser: true</code> unless that prevents you from connecting. Note that if you specify <code>useNewUrlParser: true</code>, you <strong>must</strong> specify a port in your connection string, like <code>mongodb://localhost:27017/dbname</code>. The new url parser does <em>not</em> support connection strings that do not have a port, like <code>mongodb://localhost/dbname</code>.</li>
-<li><code>useCreateIndex</code>    - False by default. Set to <code>true</code> to make Mongoose&#39;s default index build use <code>createIndex()</code> instead of <code>ensureIndex()</code> to avoid deprecation warnings from the MongoDB driver.</li>
-<li><code>useFindAndModify</code>  - True by default. Set to <code>false</code> to make <code>findOneAndUpdate()</code> and <code>findOneAndRemove()</code> use native <code>findOneAndUpdate()</code> rather than <code>findAndModify()</code>.</li>
-<li><code>autoReconnect</code>     - The underlying MongoDB driver will automatically try to reconnect when it loses connection to MongoDB. Unless you are an extremely advanced user that wants to manage their own connection pool, do <strong>not</strong> set this option to <code>false</code>.</li>
-<li><code>reconnectTries</code>    - If you&#39;re connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every <code>reconnectInterval</code> milliseconds for <code>reconnectTries</code> times, and give up afterward. When the driver gives up, the mongoose connection emits a <code>reconnectFailed</code> event. This option does nothing for replica set connections.</li>
-<li><code>reconnectInterval</code> - See <code>reconnectTries</code></li>
-<li><code>promiseLibrary</code>    - sets the <a href="http://mongodb.github.io/node-mongodb-native/2.1/api/MongoClient.html">underlying driver&#39;s promise library</a></li>
-<li><code>poolSize</code>          - The maximum number of sockets the MongoDB driver will keep open for this connection. By default, <code>poolSize</code> is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding.</li>
-<li><code>bufferMaxEntries</code>  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set <code>bufferCommands</code> to <code>false</code> on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.</li>
-<li><code>connectTimeoutMS</code>  - How long the MongoDB driver will wait before killing a socket due to inactivity <em>during initial connection</em>. Defaults to 30000. This option is passed transparently to <a href="https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback">Node.js&#39; <code>socket#setTimeout()</code> function</a>.</li>
-<li><code>socketTimeoutMS</code>   - How long the MongoDB driver will wait before killing a socket due to inactivity <em>after initial connection</em>. A socket may be inactive because of either no activity or a long-running operation. This is set to <code>30000</code> by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to <a href="https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback">Node.js <code>socket#setTimeout()</code> function</a> after the MongoDB driver successfully completes.</li>
-<li><code>family</code>            - Whether to connect using IPv4 or IPv6. This option passed to <a href="https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback">Node.js&#39; <code>dns.lookup()</code></a> function. If you don&#39;t specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your <code>mongoose.connect(uri)</code> call takes a long time, try <code>mongoose.connect(uri, { family: 4 })</code></li>
-</ul>
-<p>Example:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> options = {
-  useNewUrlParser: <span class="hljs-literal">true</span>,
-  useCreateIndex: <span class="hljs-literal">true</span>,
-  useFindAndModify: <span class="hljs-literal">false</span>,
-  autoIndex: <span class="hljs-literal">false</span>, <span class="hljs-comment">// Don't build indexes</span>
-  reconnectTries: <span class="hljs-built_in">Number</span>.MAX_VALUE, <span class="hljs-comment">// Never stop trying to reconnect</span>
-  reconnectInterval: <span class="hljs-number">500</span>, <span class="hljs-comment">// Reconnect every 500ms</span>
-  poolSize: <span class="hljs-number">10</span>, <span class="hljs-comment">// Maintain up to 10 socket connections</span>
-  <span class="hljs-comment">// If not connected, return errors immediately rather than waiting for reconnect</span>
-  bufferMaxEntries: <span class="hljs-number">0</span>,
-  connectTimeoutMS: <span class="hljs-number">10000</span>, <span class="hljs-comment">// Give up initial connection after 10 seconds</span>
-  socketTimeoutMS: <span class="hljs-number">45000</span>, <span class="hljs-comment">// Close sockets after 45 seconds of inactivity</span>
-  family: <span class="hljs-number">4</span> <span class="hljs-comment">// Use IPv4, skip trying IPv6</span>
-};
-mongoose.connect(uri, options);</code></pre>
-<p>See <a href="http://mongodb.github.io/node-mongodb-native/3.1/reference/faq/">this page</a> for more information about <code>connectTimeoutMS</code> and <code>socketTimeoutMS</code></p>
-<h3 id="callback"><a href="#callback">Callback</a></h3>
-
-<p>The <code>connect()</code> function also accepts a callback parameter and returns a
-<a href="./promises.html">promise</a>.</p>
-<pre><code class="language-javascript">mongoose.connect(uri, options, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// Check error in initial connection. There is no 2nd param to the callback.</span>
-});
-
-<span class="hljs-comment">// Or using promises</span>
-mongoose.connect(uri, options).then(
-  () =&gt; { <span class="hljs-comment">/** ready to use. The `mongoose.connect()` promise resolves to undefined. */</span> },
-  err =&gt; { <span class="hljs-comment">/** handle initial connection error */</span> }
-);</code></pre>
-<h3 id="connection-string-options"><a href="#connection-string-options">Connection String Options</a></h3>
-
-<p>You can also specify driver options in your connection string as
-<a href="https://en.wikipedia.org/wiki/Query_string">parameters in the query string</a>
-portion of the URI. This only applies to options passed to the MongoDB
-driver. You <strong>can&#39;t</strong> set Mongoose-specific options like <code>bufferCommands</code>
-in the query string.</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/test?connectTimeoutMS=1000&amp;bufferCommands=false'</span>);
-<span class="hljs-comment">// The above is equivalent to:</span>
-mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/test'</span>, {
-  connectTimeoutMS: <span class="hljs-number">1000</span>
-  <span class="hljs-comment">// Note that mongoose will **not** pull `bufferCommands` from the query string</span>
-});</code></pre>
-<p>The disadvantage of putting options in the query string is that query
-string options are harder to read. The advantage is that you only need a
-single configuration option, the URI, rather than separate options for
-<code>socketTimeoutMS</code>, <code>connectTimeoutMS</code>, etc. Best practice is to put options
-that likely differ between development and production, like <code>replicaSet</code>
-or <code>ssl</code>, in the connection string, and options that should remain constant,
-like <code>connectTimeoutMS</code> or <code>poolSize</code>, in the options object.</p>
-<p>The MongoDB docs have a full list of
-<a href="https://docs.mongodb.com/manual/reference/connection-string/">supported connection string options</a></p>
-<h3 id="connection-events"><a href="#connection-events">Connection Events</a></h3>
-
-<p>Connections inherit from <a href="https://nodejs.org/api/events.html#events_class_eventemitter">Node.js&#39; <code>EventEmitter</code> class</a>,
-and emit events when something happens to the connection, like losing
-connectivity to the MongoDB server. Below is a list of events that a
-connection may emit.</p>
-<ul>
-<li><code>connecting</code>: Emitted when Mongoose starts making its initial connection to the MongoDB server</li>
-<li><code>connected</code>: Emitted when Mongoose successfully makes its initial connection to the MongoDB server</li>
-<li><code>open</code>: Equivalent to <code>connected</code></li>
-<li><code>disconnecting</code>: Your app called <a href="api.html#connection_Connection-close"><code>Connection#close()</code></a> to disconnect from MongoDB</li>
-<li><code>disconnected</code>: Emitted when Mongoose lost connection to the MongoDB server. This event may be due to your code explicitly closing the connection, the database server crashing, or network connectivity issues.</li>
-<li><code>close</code>: Emitted after <a href="api.html#connection_Connection-close"><code>Connection#close()</code></a> successfully closes the connection. If you call <code>conn.close()</code>, you&#39;ll get both a &#39;disconnected&#39; event and a &#39;close&#39; event.</li>
-<li><code>reconnected</code>: Emitted if Mongoose lost connectivity to MongoDB and successfully reconnected. Mongoose attempts to <a href="https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html">automatically reconnect</a> when it loses connection to the database.</li>
-<li><code>error</code>: Emitted if an error occurs on a connection, like a <code>parseError</code> due to malformed data or a payload larger than <a href="https://docs.mongodb.com/manual/reference/limits/#BSON-Document-Size">16MB</a>.</li>
-<li><code>fullsetup</code>: Emitted when you&#39;re connecting to a replica set and Mongoose has successfully connected to the primary and at least one secondary.</li>
-<li><code>all</code>: Emitted when you&#39;re connecting to a replica set and Mongoose has successfully connected to all servers specified in your connection string.</li>
-<li><code>reconnectFailed</code>: Emitted when you&#39;re connected to a standalone server and Mongoose has run out of <a href="https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html#handling-single-server-outages"><code>reconnectTries</code></a>. The <a href="http://npmjs.com/package/mongodb">MongoDB driver</a> will no longer attempt to reconnect after this event is emitted. This event will never be emitted if you&#39;re connected to a replica set.</li>
-</ul>
-<h3 id="keepAlive"><a href="#keepAlive">A note about keepAlive</a></h3>
-
-<p>For long running applications, it is often prudent to enable <code>keepAlive</code>
-with a number of milliseconds. Without it, after some period of time
-you may start to see <code>&quot;connection closed&quot;</code> errors for what seems like
-no reason. If so, after
-<a href="http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/overview.html">reading this</a>,
-you may decide to enable <code>keepAlive</code>:</p>
-<pre><code class="language-javascript">mongoose.connect(uri, { keepAlive: <span class="hljs-literal">true</span>, keepAliveInitialDelay: <span class="hljs-number">300000</span> });</code></pre>
-<p><code>keepAliveInitialDelay</code> is the number of milliseconds to wait before initiating <code>keepAlive</code> on the socket.
-<code>keepAlive</code> is true by default since mongoose 5.2.0.</p>
-<h3 id="replicaset_connections"><a href="#replicaset_connections">Replica Set Connections</a></h3>
-
-<p>To connect to a replica set you pass a comma delimited list of hosts to
-connect to rather than a single host.</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]'</span> [, options]);</code></pre>
-<p>For example:</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://user:pw@host1.com:27017,host2.com:27017,host3.com:27017/testdb'</span>);</code></pre>
-<p>To connect to a single node replica set, specify the <code>replicaSet</code> option.</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://host1:port1/?replicaSet=rsName'</span>);</code></pre>
-<h3 id="replicaset-hostnames"><a href="#replicaset-hostnames">Replica Set Host Names</a></h3>
-
-<p>MongoDB replica sets rely on being able to reliably figure out the domain name
-for each member. On Linux and OSX, the MongoDB server uses the output of the
-<a href="https://linux.die.net/man/1/hostname"><code>hostname</code> command</a> to figure out the
-domain name to report to the replica set. This can cause confusing errors
-if you&#39;re connecting to a remote MongoDB replica set running on a machine that
-reports its <code>hostname</code> as <code>localhost</code>:</p>
-<pre><code><span class="hljs-comment">// Can get this error even if your connection string doesn't include</span>
-<span class="hljs-comment">// `localhost` if `rs.conf()` reports that one replica set member has</span>
-<span class="hljs-comment">// `localhost` as its host name.</span>
-failed to connect to server [localhost:<span class="hljs-number">27017</span>] on first connect</code></pre><p>If you&#39;re experiencing a similar error, connect to the replica set using the
-<code>mongo</code> shell and run the
-<a href="https://docs.mongodb.com/manual/reference/method/rs.conf/"><code>rs.conf()</code></a> command to check the host names of each replica set member. Follow
-<a href="https://docs.mongodb.com/manual/tutorial/change-hostnames-in-a-replica-set/#change-hostnames-while-maintaining-replica-set-availability">this page&#39;s instructions to change a replica set member&#39;s host name</a>.</p>
-<h3 id="mongos_connections"><a href="#mongos_connections">Multi-mongos support</a></h3>
-
-<p>You can also connect to multiple <a href="https://docs.mongodb.com/manual/reference/program/mongos/">mongos</a> instances
-for high availability in a sharded cluster. You do
-<a href="http://mongodb.github.io/node-mongodb-native/3.0/tutorials/connect/#connect-to-sharded-cluster">not need to pass any special options to connect to multiple mongos</a> in mongoose 5.x.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Connect to 2 mongos servers</span>
-mongoose.connect(<span class="hljs-string">'mongodb://mongosA:27501,mongosB:27501'</span>, cb);</code></pre>
-<h3 id="multiple_connections"><a href="#multiple_connections">Multiple connections</a></h3>
-
-<p>So far we&#39;ve seen how to connect to MongoDB using Mongoose&#39;s default
-connection. At times we may need multiple connections open to Mongo, each
-with different read/write settings, or maybe just to different databases for
-example. In these cases we can utilize <code>mongoose.createConnection()</code> which
-accepts all the arguments already discussed and returns a fresh connection
-for you.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> conn = mongoose.createConnection(<span class="hljs-string">'mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]'</span>, options);</code></pre>
-<p>This <a href="./api.html#connection_Connection">connection</a> object is then used to
-create and retrieve <a href="./api.html#model_Model">models</a>. Models are
-<strong>always</strong> scoped to a single connection.</p>
-<p>Mongoose creates a <em>default connection</em> when you call <code>mongoose.connect()</code>.
-You can access the default connection using <code>mongoose.connection</code>.</p>
-<h3 id="connection_pools"><a href="#connection_pools">Connection Pools</a></h3>
-
-<p>Each <code>connection</code>, whether created with <code>mongoose.connect</code> or
-<code>mongoose.createConnection</code> are all backed by an internal configurable
-connection pool defaulting to a maximum size of 5. Adjust the pool size
-using your connection options:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// With object options</span>
-mongoose.createConnection(uri, { poolSize: <span class="hljs-number">4</span> });
-
-<span class="hljs-keyword">const</span> uri = <span class="hljs-string">'mongodb://localhost:27017/test?poolSize=4'</span>;
-mongoose.createConnection(uri);</code></pre>
-<h3 id="v5-changes"><a href="#v5-changes">Option Changes in v5.x</a></h3>
-
-<p>You may see the following deprecation warning if upgrading from 4.x to 5.x
-and you didn&#39;t use the <code>useMongoClient</code> option in 4.x:</p>
-<pre><code>the server/replset/mongos options are deprecated, all their options are supported at the top level <span class="hljs-keyword">of</span> the options object</code></pre><p>In older version of the MongoDB driver you had to specify distinct options
-for server connections, replica set connections, and mongos connections:</p>
-<pre><code class="language-javascript">mongoose.connect(myUri, {
-  server: {
-    socketOptions: {
-      socketTimeoutMS: <span class="hljs-number">0</span>,
-      keepAlive: <span class="hljs-literal">true</span>
-    },
-    reconnectTries: <span class="hljs-number">30</span>
-  },
-  replset: {
-    socketOptions: {
-      socketTimeoutMS: <span class="hljs-number">0</span>,
-      keepAlive: <span class="hljs-literal">true</span>
-    },
-    reconnectTries: <span class="hljs-number">30</span>
-  },
-  mongos: {
-    socketOptions: {
-      socketTimeoutMS: <span class="hljs-number">0</span>,
-      keepAlive: <span class="hljs-literal">true</span>
-    },
-    reconnectTries: <span class="hljs-number">30</span>
-  }
-});</code></pre>
-<p>In mongoose v5.x you can instead declare these options at the top level,
-without all that extra nesting.
-<a href="http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html">Here&#39;s the list of all supported options</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Equivalent to the above code</span>
-mongoose.connect(myUri, {
-  socketTimeoutMS: <span class="hljs-number">0</span>,
-  keepAlive: <span class="hljs-literal">true</span>,
-  reconnectTries: <span class="hljs-number">30</span>
-});</code></pre>
-<h3 id="next">Next Up</h3>
-
-<p>Now that we&#39;ve covered connections, let&#39;s take a look at <a href="/docs/models.html">models</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/contributing.html b/docs/contributing.html
deleted file mode 100644
index 5201142cd0d..00000000000
--- a/docs/contributing.html
+++ /dev/null
@@ -1,55 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Contributing</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="contributing">Contributing</h2>
-<p>Please read all about contributing <a href="https://github.com/Automattic/mongoose/blob/master/CONTRIBUTING.md">here</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/customschematypes.html b/docs/customschematypes.html
deleted file mode 100644
index 74308395820..00000000000
--- a/docs/customschematypes.html
+++ /dev/null
@@ -1,99 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Custom Schema Types</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><ul class="toc"><li><a href="##{block.identifier}">Creating a Basic Custom Schema Type</a></li></ul><h2 id="#{block.identifier}"><a href="##{block.identifier}">Creating a Basic Custom Schema Type</a></h2><p><em>New in Mongoose 4.4.0:</em> Mongoose supports custom types. Before you
-reach for a custom type, however, know that a custom type is overkill
-for most use cases. You can do most basic tasks with
-<a href="http://mongoosejs.com/docs/2.7.x/docs/getters-setters.html">custom getters/setters</a>,
-<a href="http://mongoosejs.com/docs/guide.html#virtuals">virtuals</a>, and
-<a href="http://mongoosejs.com/docs/subdocs.html#single-embedded">single embedded docs</a>.</p>
-<p>Let&#39;s take a look at an example of a basic schema type: a 1-byte integer.
-To create a new schema type, you need to inherit from <code>mongoose.SchemaType</code>
-and add the corresponding property to <code>mongoose.Schema.Types</code>. The one
-method you need to implement is the <code>cast()</code> method.</p>
-
-<pre><code class="language-javascript"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">Int8</span>(<span class="hljs-params">key, options</span>) </span>{
-  mongoose.SchemaType.call(<span class="hljs-keyword">this</span>, key, options, <span class="hljs-string">'Int8'</span>);
-}
-Int8.prototype = <span class="hljs-built_in">Object</span>.create(mongoose.SchemaType.prototype);
-
-<span class="hljs-comment">// `cast()` takes a parameter that can be anything. You need to</span>
-<span class="hljs-comment">// validate the provided `val` and throw a `CastError` if you</span>
-<span class="hljs-comment">// can't convert it.</span>
-Int8.prototype.cast = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">val</span>) </span>{
-  <span class="hljs-keyword">var</span> _val = <span class="hljs-built_in">Number</span>(val);
-  <span class="hljs-keyword">if</span> (<span class="hljs-built_in">isNaN</span>(_val)) {
-    <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Int8: '</span> + val + <span class="hljs-string">' is not a number'</span>);
-  }
-  _val = <span class="hljs-built_in">Math</span>.round(_val);
-  <span class="hljs-keyword">if</span> (_val &lt; <span class="hljs-number">-0x80</span> || _val &gt; <span class="hljs-number">0x7F</span>) {
-    <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Int8: '</span> + val +
-      <span class="hljs-string">' is outside of the range of valid 8-bit ints'</span>);
-  }
-  <span class="hljs-keyword">return</span> _val;
-};
-
-<span class="hljs-comment">// Don't forget to add `Int8` to the type registry</span>
-mongoose.Schema.Types.Int8 = Int8;
-
-<span class="hljs-keyword">var</span> testSchema = <span class="hljs-keyword">new</span> Schema({ test: Int8 });
-<span class="hljs-keyword">var</span> Test = mongoose.model(<span class="hljs-string">'CustomTypeExample'</span>, testSchema);
-
-<span class="hljs-keyword">var</span> t = <span class="hljs-keyword">new</span> Test();
-t.test = <span class="hljs-string">'abc'</span>;
-assert.ok(t.validateSync());
-assert.equal(t.validateSync().errors[<span class="hljs-string">'test'</span>].name, <span class="hljs-string">'CastError'</span>);
-assert.equal(t.validateSync().errors[<span class="hljs-string">'test'</span>].message,
-  <span class="hljs-string">'Cast to Int8 failed for value "abc" at path "test"'</span>);
-assert.equal(t.validateSync().errors[<span class="hljs-string">'test'</span>].reason.message,
-  <span class="hljs-string">'Int8: abc is not a number'</span>);</code></pre>
-<div class="suffix"></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/defaults.html b/docs/defaults.html
deleted file mode 100644
index 32b886c0fd2..00000000000
--- a/docs/defaults.html
+++ /dev/null
@@ -1,168 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Defaults</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><ul class="toc"><li><a href="##{block.identifier}">Declaring defaults in your schema</a></li><li><a href="##{block.identifier}">Default functions</a></li><li><a href="##{block.identifier}">The <code>setDefaultsOnInsert</code> option</a></li><li><a href="##{block.identifier}">Default functions and <code>this</code></a></li></ul><h2 id="#{block.identifier}"><a href="##{block.identifier}">Declaring defaults in your schema</a></h2><p>Your schemas can define default values for certain paths. If you create
-a new document without that path set, the default will kick in.</p>
-<p>Note: Mongoose only applies a default if the value of the path is
-strictly <code>undefined</code>.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  role: { type: <span class="hljs-built_in">String</span>, <span class="hljs-keyword">default</span>: <span class="hljs-string">'guitarist'</span> }
-});
-
-<span class="hljs-keyword">var</span> Person = db.model(<span class="hljs-string">'Person'</span>, schema);
-
-<span class="hljs-keyword">var</span> axl = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'Axl Rose'</span>, role: <span class="hljs-string">'singer'</span> });
-assert.equal(axl.role, <span class="hljs-string">'singer'</span>);
-
-<span class="hljs-keyword">var</span> slash = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'Slash'</span> });
-assert.equal(slash.role, <span class="hljs-string">'guitarist'</span>);
-
-<span class="hljs-keyword">var</span> izzy = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'Izzy'</span>, role: <span class="hljs-literal">undefined</span> });
-assert.equal(izzy.role, <span class="hljs-string">'guitarist'</span>);
-
-<span class="hljs-comment">// Defaults do **not** run on `null`, `''`, or value other than `undefined`.</span>
-<span class="hljs-keyword">var</span> foo = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'Bar'</span>, role: <span class="hljs-literal">null</span> });
-assert.strictEqual(foo.role, <span class="hljs-literal">null</span>);
-
-Person.create(axl, slash, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  assert.ifError(error);
-  Person.find({ role: <span class="hljs-string">'guitarist'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, docs</span>) </span>{
-    assert.ifError(error);
-    assert.equal(docs.length, <span class="hljs-number">1</span>);
-    assert.equal(docs[<span class="hljs-number">0</span>].name, <span class="hljs-string">'Slash'</span>);
-  });
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Default functions</a></h2><p>You can also set the <code>default</code> schema option to a function. Mongoose will
-execute that function and use the return value as the default.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  title: <span class="hljs-built_in">String</span>,
-  date: {
-    type: <span class="hljs-built_in">Date</span>,
-    <span class="hljs-comment">// `Date.now()` returns the current unix timestamp as a number</span>
-    <span class="hljs-keyword">default</span>: <span class="hljs-built_in">Date</span>.now
-  }
-});
-
-<span class="hljs-keyword">var</span> BlogPost = db.model(<span class="hljs-string">'BlogPost'</span>, schema);
-
-<span class="hljs-keyword">var</span> post = <span class="hljs-keyword">new</span> BlogPost({title: <span class="hljs-string">'5 Best Arnold Schwarzenegger Movies'</span>});
-
-<span class="hljs-comment">// The post has a default Date set to now</span>
-assert.ok(post.date.getTime() &gt;= <span class="hljs-built_in">Date</span>.now() - <span class="hljs-number">1000</span>);
-assert.ok(post.date.getTime() &lt;= <span class="hljs-built_in">Date</span>.now());</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">The <code>setDefaultsOnInsert</code> option</a></h2><p>By default, mongoose only applies defaults when you create a new document.
-It will <strong>not</strong> set defaults if you use <code>update()</code> and
-<code>findOneAndUpdate()</code>. However, mongoose 4.x lets you opt-in to this
-behavior using the <code>setDefaultsOnInsert</code> option.</p>
-<h2 id="important">Important</h2>
-<p>The <code>setDefaultsOnInsert</code> option relies on the
-<a href="https://docs.mongodb.org/manual/reference/operator/update/setOnInsert/">MongoDB <code>$setOnInsert</code> operator</a>.
-The <code>$setOnInsert</code> operator was introduced in MongoDB 2.4. If you&#39;re
-using MongoDB server &lt; 2.4.0, do <strong>not</strong> use <code>setDefaultsOnInsert</code>.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  title: <span class="hljs-built_in">String</span>,
-  genre: {type: <span class="hljs-built_in">String</span>, <span class="hljs-keyword">default</span>: <span class="hljs-string">'Action'</span>}
-});
-
-<span class="hljs-keyword">var</span> Movie = db.model(<span class="hljs-string">'Movie'</span>, schema);
-
-<span class="hljs-keyword">var</span> query = {};
-<span class="hljs-keyword">var</span> update = {title: <span class="hljs-string">'The Terminator'</span>};
-<span class="hljs-keyword">var</span> options = {
-  <span class="hljs-comment">// Return the document after updates are applied</span>
-  <span class="hljs-keyword">new</span>: <span class="hljs-literal">true</span>,
-  <span class="hljs-comment">// Create a document if one isn't found. Required</span>
-  <span class="hljs-comment">// for `setDefaultsOnInsert`</span>
-  upsert: <span class="hljs-literal">true</span>,
-  setDefaultsOnInsert: <span class="hljs-literal">true</span>
-};
-
-Movie.
-  findOneAndUpdate(query, update, options, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error, doc</span>) </span>{
-    assert.ifError(error);
-    assert.equal(doc.title, <span class="hljs-string">'The Terminator'</span>);
-    assert.equal(doc.genre, <span class="hljs-string">'Action'</span>);
-  });</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Default functions and <code>this</code></a></h2><p>Unless it is running on a query with <code>setDefaultsOnInsert</code>, a default
-function&#39;s <code>this</code> refers to the document.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  title: <span class="hljs-built_in">String</span>,
-  released: <span class="hljs-built_in">Boolean</span>,
-  releaseDate: {
-    type: <span class="hljs-built_in">Date</span>,
-    <span class="hljs-keyword">default</span>: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-      <span class="hljs-keyword">if</span> (<span class="hljs-keyword">this</span>.released) {
-        <span class="hljs-keyword">return</span> <span class="hljs-built_in">Date</span>.now();
-      }
-      <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>;
-    }
-  }
-});
-
-<span class="hljs-keyword">const</span> Movie = db.model(<span class="hljs-string">'Movie'</span>, schema);
-
-<span class="hljs-keyword">const</span> movie1 = <span class="hljs-keyword">new</span> Movie({ title: <span class="hljs-string">'The Terminator'</span>, released: <span class="hljs-literal">true</span> });
-
-<span class="hljs-comment">// The post has a default Date set to now</span>
-assert.ok(movie1.releaseDate.getTime() &gt;= <span class="hljs-built_in">Date</span>.now() - <span class="hljs-number">1000</span>);
-assert.ok(movie1.releaseDate.getTime() &lt;= <span class="hljs-built_in">Date</span>.now());
-
-<span class="hljs-keyword">const</span> movie2 = <span class="hljs-keyword">new</span> Movie({ title: <span class="hljs-string">'The Legend of Conan'</span>, released: <span class="hljs-literal">false</span> });
-
-<span class="hljs-comment">// Since `released` is false, the default function will return null</span>
-assert.strictEqual(movie2.releaseDate, <span class="hljs-literal">null</span>);</code></pre>
-<div class="suffix"></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/deprecations.html b/docs/deprecations.html
deleted file mode 100644
index 6e397c78a2c..00000000000
--- a/docs/deprecations.html
+++ /dev/null
@@ -1,226 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Deprecation Warnings</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="deprecation-warnings">Deprecation Warnings</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>There are several deprecations in the <a href="http://npmjs.com/package/mongodb">MongoDB Node.js driver</a>
-that Mongoose users should be aware of. Mongoose provides options to work
-around these deprecation warnings, but you need to test whether these options
-cause any problems for your application. Please <a href="https://github.com/Automattic/mongoose/issues/new">report any issues on GitHub</a>.</p>
-<h2 id="summary">Summary</h2>
-<p>To fix all deprecation warnings, follow the below steps:</p>
-<ul>
-<li><code>mongoose.set(&#39;useNewUrlParser&#39;, true);</code></li>
-<li><code>mongoose.set(&#39;useFindAndModify&#39;, false);</code></li>
-<li><code>mongoose.set(&#39;useCreateIndex&#39;, true);</code></li>
-<li>Replace <code>update()</code> with <code>updateOne()</code>, <code>updateMany()</code>, or <code>replaceOne()</code></li>
-<li>Replace <code>remove()</code> with <code>deleteOne()</code> or <code>deleteMany()</code>.</li>
-<li>Replace <code>count()</code> with <code>countDocuments()</code>, unless you want to count how many documents are in the whole collection (no filter). In the latter case, use <code>estimatedDocumentCount()</code>.</li>
-</ul>
-<p>Read below for more a more detailed description of each deprecation warning.</p>
-<h2 id="the-usenewurlparser-option">The <code>useNewUrlParser</code> Option</h2>
-<p>By default, <code>mongoose.connect()</code> will print out the below warning:</p>
-<pre><code>DeprecationWarning: current URL string parser is deprecated, and will be
-removed <span class="hljs-keyword">in</span> a future version. To use the <span class="hljs-keyword">new</span> parser, pass option
-{ useNewUrlParser: <span class="hljs-literal">true</span> } to MongoClient.connect.</code></pre><p>The MongoDB Node.js driver rewrote the tool it uses to parse <a href="https://docs.mongodb.com/manual/reference/connection-string/">MongoDB connection strings</a>.
-Because this is such a big change, they put the new connection string parser
-behind a flag. To turn on this option, pass the <code>useNewUrlParser</code> option to
-<a href="/docs/api.html#mongoose_Mongoose-connect"><code>mongoose.connect()</code></a>
-or <a href="/docs/api.html#mongoose_Mongoose-createConnection"><code>mongoose.createConnection()</code></a>.</p>
-<pre><code class="language-javascript">mongoose.connect(uri, { useNewUrlParser: <span class="hljs-literal">true</span> });
-mongoose.createConnection(uri, { useNewUrlParser: <span class="hljs-literal">true</span> });</code></pre>
-<p>You can also <a href="/docs/api.html#mongoose_Mongoose-set">set the global <code>useNewUrlParser</code> option</a>
-to turn on <code>useNewUrlParser</code> for every connection by default.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Optional. Use this if you create a lot of connections and don't want</span>
-<span class="hljs-comment">// to copy/paste `{ useNewUrlParser: true }`.</span>
-mongoose.set(<span class="hljs-string">'useNewUrlParser'</span>, <span class="hljs-literal">true</span>);</code></pre>
-<p>To test your app with <code>{ useNewUrlParser: true }</code>, you only need to check
-whether your app successfully connects. Once Mongoose has successfully
-connected, the URL parser is no longer important. If you can&#39;t connect
-with <code>{ useNewUrlParser: true }</code>, please <a href="https://github.com/Automattic/mongoose/issues/new">open an issue on GitHub</a>.</p>
-<h2 id="findandmodify"><code>findAndModify()</code></h2>
-<p>If you use <a href="/docs/api.html#model_Model.findOneAndUpdate"><code>Model.findOneAndUpdate()</code></a>,
-by default you&#39;ll see one of the below deprecation warnings.</p>
-<pre><code>DeprecationWarning: Mongoose: <span class="hljs-string">`findOneAndUpdate()`</span> and <span class="hljs-string">`findOneAndDelete()`</span> without the <span class="hljs-string">`useFindAndModify`</span> option set to <span class="hljs-literal">false</span> are deprecated. See: https:<span class="hljs-comment">//mongoosejs.com/docs/deprecations.html#-findandmodify-</span>
-DeprecationWarning: collection.findAndModify is deprecated. Use findOneAndUpdate, findOneAndReplace or findOneAndDelete instead.</code></pre><p>Mongoose&#39;s <code>findOneAndUpdate()</code> long pre-dates the MongoDB driver&#39;s <code>findOneAndUpdate()</code>
-function, so it uses the MongoDB driver&#39;s <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#findAndModify"><code>findAndModify()</code> function</a>
-instead. You can opt in to using using the MongoDB driver&#39;s <code>findOneAndUpdate()</code>
-function using the <a href="/docs/api.html#mongoose_Mongoose-set"><code>useFindAndModify</code> global option</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Make Mongoose use `findOneAndUpdate()`. Note that this option is `true`</span>
-<span class="hljs-comment">// by default, you need to set it to false.</span>
-mongoose.set(<span class="hljs-string">'useFindAndModify'</span>, <span class="hljs-literal">false</span>);</code></pre>
-<p>You can also configure <code>useFindAndModify</code> by passing it through the connection options.</p>
-<pre><code class="language-javascript">mongoose.connect(uri, { useFindAndModify: <span class="hljs-literal">false</span> });</code></pre>
-<p>This option affects the following model and query functions. There are
-no intentional backwards breaking changes, so you should be able to turn
-this option on without any code changes. If you discover any issues,
-please <a href="https://github.com/Automattic/mongoose/issues/new">open an issue on GitHub</a>.</p>
-<ul>
-<li><a href="/docs/api.html#model_Model.findByIdAndDelete"><code>Model.findByIdAndDelete()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findByIdAndRemove"><code>Model.findByIdAndRemove()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findByIdAndUpdate"><code>Model.findByIdAndUpdate()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOneAndDelete"><code>Model.findOneAndDelete()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOneAndRemove"><code>Model.findOneAndRemove()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOneAndUpdate"><code>Model.findOneAndUpdate()</code></a></li>
-<li><a href="/docs/api.html#query_Query-findOneAndDelete"><code>Query.findOneAndDelete()</code></a></li>
-<li><a href="/docs/api.html#query_Query-findOneAndRemove"><code>Query.findOneAndRemove()</code></a></li>
-<li><a href="/docs/api.html#query_Query-findOneAndUpdate"><code>Query.findOneAndUpdate()</code></a></li>
-</ul>
-<h2 id="ensureindex"><code>ensureIndex()</code></h2>
-<p>If you define <a href="https://mongoosejs.com/docs/guide.html#indexes">indexes in your Mongoose schemas</a>, you&#39;ll see the below
-deprecation warning.</p>
-<pre><code>DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes
-instead.</code></pre><p>By default, Mongoose 5.x calls the <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#ensureIndex">MongoDB driver&#39;s <code>ensureIndex()</code> function</a>.
-The MongoDB driver deprecated this function in favor of <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#createIndex"><code>createIndex()</code></a>.
-Set the <a href="/docs/api.html#mongoose_Mongoose-set"><code>useCreateIndex</code> global option</a> to opt in to making Mongoose use <code>createIndex()</code> instead.</p>
-<pre><code class="language-javascript">mongoose.set(<span class="hljs-string">'useCreateIndex'</span>, <span class="hljs-literal">true</span>);</code></pre>
-<p>You can also configure <code>useCreateIndex</code> by passing it through the connection options.</p>
-<pre><code class="language-javascript">mongoose.connect(uri, { useCreateIndex: <span class="hljs-literal">true</span> });</code></pre>
-<p>There are no intentional backwards breaking changes with the <code>useCreateIndex</code>
-option, so you should be able to turn
-this option on without any code changes. If you discover any issues,
-please <a href="https://github.com/Automattic/mongoose/issues/new">open an issue on GitHub</a>.</p>
-<h2 id="remove"><code>remove()</code></h2>
-<p>The MongoDB driver&#39;s <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove"><code>remove()</code> function</a> is deprecated in favor of <code>deleteOne()</code> and <code>deleteMany()</code>. This is to comply with
-the <a href="https://github.com/mongodb/specifications/blob/master/source/crud/crud.rst">MongoDB CRUD specification</a>,
-which aims to provide a consistent API for CRUD operations across all MongoDB
-drivers.</p>
-<pre><code>DeprecationWarning: collection.remove is deprecated. Use deleteOne,
-deleteMany, or bulkWrite instead.</code></pre><p>To remove this deprecation warning, replace any usage of <code>remove()</code> with
-<code>deleteMany()</code>, <em>unless</em> you specify the <a href="/docs/api.html#model_Model.remove"><code>single</code> option to <code>remove()</code></a>. The <code>single</code>
-option limited <code>remove()</code> to deleting at most one document, so you should
-replace <code>remove(filter, { single: true })</code> with <code>deleteOne(filter)</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Replace this:</span>
-MyModel.remove({ foo: <span class="hljs-string">'bar'</span> });
-<span class="hljs-comment">// With this:</span>
-MyModel.deleteMany({ foo: <span class="hljs-string">'bar'</span> });
-
-<span class="hljs-comment">// Replace this:</span>
-MyModel.remove({ answer: <span class="hljs-number">42</span> }, { single: <span class="hljs-literal">true</span> });
-<span class="hljs-comment">// With this:</span>
-MyModel.deleteOne({ answer: <span class="hljs-number">42</span> });</code></pre>
-<h2 id="update"><code>update()</code></h2>
-<p>Like <code>remove()</code>, the <a href="/docs/api.html#model_Model.update"><code>update()</code> function</a> is deprecated in favor
-of the more explicit <a href="/docs/api.html#model_Model.updateOne"><code>updateOne()</code></a>, <a href="/docs/api.html#model_Model.updateMany"><code>updateMany()</code></a>, and <a href="/docs/api.html#model_Model.replaceOne"><code>replaceOne()</code></a> functions. You should replace
-<code>update()</code> with <code>updateOne()</code>, unless you use the <a href="/docs/api.html#model_Model.update"><code>multi</code> or <code>overwrite</code> options</a>.</p>
-<pre><code>collection.update is deprecated. Use updateOne, updateMany, or bulkWrite
-instead.</code></pre><pre><code class="language-javascript"><span class="hljs-comment">// Replace this:</span>
-MyModel.update({ foo: <span class="hljs-string">'bar'</span> }, { answer: <span class="hljs-number">42</span> });
-<span class="hljs-comment">// With this:</span>
-MyModel.updateOne({ foo: <span class="hljs-string">'bar'</span> }, { answer: <span class="hljs-number">42</span> });
-
-<span class="hljs-comment">// If you use `overwrite: true`, you should use `replaceOne()` instead:</span>
-MyModel.update(filter, update, { overwrite: <span class="hljs-literal">true</span> });
-<span class="hljs-comment">// Replace with this:</span>
-MyModel.replaceOne(filter, update);
-
-<span class="hljs-comment">// If you use `multi: true`, you should use `updateMany()` instead:</span>
-MyModel.update(filter, update, { multi: <span class="hljs-literal">true</span> });
-<span class="hljs-comment">// Replace with this:</span>
-MyModel.updateMany(filter, update);</code></pre>
-<h2 id="count"><code>count()</code></h2>
-<p>The MongoDB server has deprecated the <code>count()</code> function in favor of two
-separate functions, <a href="#query_Query-countDocuments"><code>countDocuments()</code></a> and
-<a href="#query_Query-estimatedDocumentCount"><code>estimatedDocumentCount()</code></a>.</p>
-<pre><code>DeprecationWarning: collection.count is deprecated, and will be removed <span class="hljs-keyword">in</span> a future version. Use collection.countDocuments or collection.estimatedDocumentCount instead</code></pre><p>The difference between the two is <code>countDocuments()</code> can accept a filter
-parameter like <a href="#query_Query-find"><code>find()</code></a>. The <code>estimatedDocumentCount()</code>
-function is faster, but can only tell you the total number of documents in
-a collection. You cannot pass a <code>filter</code> to <code>estimatedDocumentCount()</code>.</p>
-<p>To migrate, replace <code>count()</code> with <code>countDocuments()</code> <em>unless</em> you do not
-pass any arguments to <code>count()</code>. If you use <code>count()</code> to count all documents
-in a collection as opposed to counting documents that match a query, use
-<code>estimatedDocumentCount()</code> instead of <code>countDocuments()</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Replace this:</span>
-MyModel.count({ answer: <span class="hljs-number">42</span> });
-<span class="hljs-comment">// With this:</span>
-MyModel.countDocuments({ answer: <span class="hljs-number">42</span> });
-
-<span class="hljs-comment">// If you're counting all documents in the collection, use</span>
-<span class="hljs-comment">// `estimatedDocumentCount()` instead.</span>
-MyModel.count();
-<span class="hljs-comment">// Replace with:</span>
-MyModel.estimatedDocumentCount();
-
-<span class="hljs-comment">// Replace this:</span>
-MyModel.find({ answer: <span class="hljs-number">42</span> }).count().exec();
-<span class="hljs-comment">// With this:</span>
-MyModel.find({ answer: <span class="hljs-number">42</span> }).countDocuments().exec();
-
-<span class="hljs-comment">// Replace this:</span>
-MyModel.find().count().exec();
-<span class="hljs-comment">// With this, since there's no filter</span>
-MyModel.find().estimatedDocumentCount().exec();</code></pre>
-<h2 id="gridstore"><code>GridStore</code></h2>
-<p>If you&#39;re using <a href="https://www.npmjs.com/package/gridfs-stream">gridfs-stream</a>,
-you&#39;ll see the below deprecation warning:</p>
-<pre><code>DeprecationWarning: GridStore is deprecated, and will be removed <span class="hljs-keyword">in</span> a
-future version. Please use GridFSBucket instead.</code></pre><p>That is because gridfs-stream relies on a <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/GridStore.html">deprecated MongoDB driver class</a>.
-You should instead use the <a href="https://thecodebarbarian.com/mongodb-gridfs-stream">MongoDB driver&#39;s own streaming API</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Replace this:</span>
-<span class="hljs-keyword">const</span> conn = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/gfstest'</span>);
-<span class="hljs-keyword">const</span> gfs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'gridfs-store'</span>)(conn.db);
-<span class="hljs-keyword">const</span> writeStream = gfs.createWriteStream({ filename: <span class="hljs-string">'test.dat'</span> });
-
-<span class="hljs-comment">// With this:</span>
-<span class="hljs-keyword">const</span> conn = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/gfstest'</span>);
-<span class="hljs-keyword">const</span> gridFSBucket = <span class="hljs-keyword">new</span> mongoose.mongo.GridFSBucket(conn.db);
-<span class="hljs-keyword">const</span> writeStream = gridFSBucket.openUploadStream(<span class="hljs-string">'test.dat'</span>);</code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/discriminators.html b/docs/discriminators.html
deleted file mode 100644
index 55ebe269735..00000000000
--- a/docs/discriminators.html
+++ /dev/null
@@ -1,352 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Discriminators</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><ul class="toc"><li><a href="##{block.identifier}">The <code>model.discriminator()</code> function</a></li><li><a href="##{block.identifier}">Discriminators save to the Event model&#39;s collection</a></li><li><a href="##{block.identifier}">Discriminator keys</a></li><li><a href="##{block.identifier}">Discriminators add the discriminator key to queries</a></li><li><a href="##{block.identifier}">Discriminators copy pre and post hooks</a></li><li><a href="##{block.identifier}">Handling custom _id fields</a></li><li><a href="##{block.identifier}">Using discriminators with <code>Model.create()</code></a></li><li><a href="##{block.identifier}">Embedded discriminators in arrays</a></li><li><a href="##{block.identifier}">Recursive embedded discriminators in arrays</a></li></ul><h2 id="#{block.identifier}"><a href="##{block.identifier}">The <code>model.discriminator()</code> function</a></h2><p>Discriminators are a schema inheritance mechanism. They enable
-you to have multiple models with overlapping schemas on top of the
-same underlying MongoDB collection.</p>
-<p>Suppose you wanted to track different types of events in a single
-collection. Every event will have a timestamp, but events that
-represent clicked links should have a URL. You can achieve this
-using the <code>model.discriminator()</code> function. This function takes
-3 parameters, a model name, a discriminator schema and an optional
-key (defaults to the model name). It returns a model whose schema
-is the union of the base schema and the discriminator schema.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> options = {discriminatorKey: <span class="hljs-string">'kind'</span>};
-
-<span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> mongoose.Schema({time: <span class="hljs-built_in">Date</span>}, options);
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'Event'</span>, eventSchema);
-
-<span class="hljs-comment">// ClickedLinkEvent is a special type of Event that has</span>
-<span class="hljs-comment">// a URL.</span>
-<span class="hljs-keyword">var</span> ClickedLinkEvent = Event.discriminator(<span class="hljs-string">'ClickedLink'</span>,
-  <span class="hljs-keyword">new</span> mongoose.Schema({url: <span class="hljs-built_in">String</span>}, options));
-
-<span class="hljs-comment">// When you create a generic event, it can't have a URL field...</span>
-<span class="hljs-keyword">var</span> genericEvent = <span class="hljs-keyword">new</span> Event({time: <span class="hljs-built_in">Date</span>.now(), url: <span class="hljs-string">'google.com'</span>});
-assert.ok(!genericEvent.url);
-
-<span class="hljs-comment">// But a ClickedLinkEvent can</span>
-<span class="hljs-keyword">var</span> clickedEvent =
-  <span class="hljs-keyword">new</span> ClickedLinkEvent({time: <span class="hljs-built_in">Date</span>.now(), url: <span class="hljs-string">'google.com'</span>});
-assert.ok(clickedEvent.url);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Discriminators save to the Event model&#39;s collection</a></h2><p>Suppose you created another discriminator to track events where
-a new user registered. These <code>SignedUpEvent</code> instances will be
-stored in the same collection as generic events and <code>ClickedLinkEvent</code>
-instances.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> event1 = <span class="hljs-keyword">new</span> Event({time: <span class="hljs-built_in">Date</span>.now()});
-<span class="hljs-keyword">var</span> event2 = <span class="hljs-keyword">new</span> ClickedLinkEvent({time: <span class="hljs-built_in">Date</span>.now(), url: <span class="hljs-string">'google.com'</span>});
-<span class="hljs-keyword">var</span> event3 = <span class="hljs-keyword">new</span> SignedUpEvent({time: <span class="hljs-built_in">Date</span>.now(), user: <span class="hljs-string">'testuser'</span>});
-
-<span class="hljs-keyword">var</span> save = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, callback</span>) </span>{
-  doc.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error, doc</span>) </span>{
-    callback(error, doc);
-  });
-};
-
-<span class="hljs-keyword">async</span>.map([event1, event2, event3], save, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error</span>) </span>{
-
-  Event.countDocuments({}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error, count</span>) </span>{
-    assert.equal(count, <span class="hljs-number">3</span>);
-  });
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Discriminator keys</a></h2><p>The way mongoose tells the difference between the different
-discriminator models is by the &#39;discriminator key&#39;, which is
-<code>__t</code> by default. Mongoose adds a String path called <code>__t</code>
-to your schemas that it uses to track which discriminator
-this document is an instance of.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> event1 = <span class="hljs-keyword">new</span> Event({time: <span class="hljs-built_in">Date</span>.now()});
-<span class="hljs-keyword">var</span> event2 = <span class="hljs-keyword">new</span> ClickedLinkEvent({time: <span class="hljs-built_in">Date</span>.now(), url: <span class="hljs-string">'google.com'</span>});
-<span class="hljs-keyword">var</span> event3 = <span class="hljs-keyword">new</span> SignedUpEvent({time: <span class="hljs-built_in">Date</span>.now(), user: <span class="hljs-string">'testuser'</span>});
-
-assert.ok(!event1.__t);
-assert.equal(event2.__t, <span class="hljs-string">'ClickedLink'</span>);
-assert.equal(event3.__t, <span class="hljs-string">'SignedUp'</span>);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Discriminators add the discriminator key to queries</a></h2><p>Discriminator models are special; they attach the discriminator key
-to queries. In other words, <code>find()</code>, <code>count()</code>, <code>aggregate()</code>, etc.
-are smart enough to account for discriminators.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> event1 = <span class="hljs-keyword">new</span> Event({time: <span class="hljs-built_in">Date</span>.now()});
-<span class="hljs-keyword">var</span> event2 = <span class="hljs-keyword">new</span> ClickedLinkEvent({time: <span class="hljs-built_in">Date</span>.now(), url: <span class="hljs-string">'google.com'</span>});
-<span class="hljs-keyword">var</span> event3 = <span class="hljs-keyword">new</span> SignedUpEvent({time: <span class="hljs-built_in">Date</span>.now(), user: <span class="hljs-string">'testuser'</span>});
-
-<span class="hljs-keyword">var</span> save = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc, callback</span>) </span>{
-  doc.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error, doc</span>) </span>{
-    callback(error, doc);
-  });
-};
-
-<span class="hljs-keyword">async</span>.map([event1, event2, event3], save, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error</span>) </span>{
-
-  ClickedLinkEvent.find({}, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">error, docs</span>) </span>{
-    assert.equal(docs.length, <span class="hljs-number">1</span>);
-    assert.equal(docs[<span class="hljs-number">0</span>]._id.toString(), event2._id.toString());
-    assert.equal(docs[<span class="hljs-number">0</span>].url, <span class="hljs-string">'google.com'</span>);
-  });
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Discriminators copy pre and post hooks</a></h2><p>Discriminators also take their base schema&#39;s pre and post middleware.
-However, you can also attach middleware to the discriminator schema
-without affecting the base schema.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> options = {discriminatorKey: <span class="hljs-string">'kind'</span>};
-
-<span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> mongoose.Schema({time: <span class="hljs-built_in">Date</span>}, options);
-<span class="hljs-keyword">var</span> eventSchemaCalls = <span class="hljs-number">0</span>;
-eventSchema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">next</span>) </span>{
-  ++eventSchemaCalls;
-  next();
-});
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'GenericEvent'</span>, eventSchema);
-
-<span class="hljs-keyword">var</span> clickedLinkSchema = <span class="hljs-keyword">new</span> mongoose.Schema({url: <span class="hljs-built_in">String</span>}, options);
-<span class="hljs-keyword">var</span> clickedSchemaCalls = <span class="hljs-number">0</span>;
-clickedLinkSchema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">next</span>) </span>{
-  ++clickedSchemaCalls;
-  next();
-});
-<span class="hljs-keyword">var</span> ClickedLinkEvent = Event.discriminator(<span class="hljs-string">'ClickedLinkEvent'</span>,
-  clickedLinkSchema);
-
-<span class="hljs-keyword">var</span> event1 = <span class="hljs-keyword">new</span> ClickedLinkEvent();
-event1.validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  assert.equal(eventSchemaCalls, <span class="hljs-number">1</span>);
-  assert.equal(clickedSchemaCalls, <span class="hljs-number">1</span>);
-
-  <span class="hljs-keyword">var</span> generic = <span class="hljs-keyword">new</span> Event();
-  generic.validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-    assert.equal(eventSchemaCalls, <span class="hljs-number">2</span>);
-    assert.equal(clickedSchemaCalls, <span class="hljs-number">1</span>);
-  });
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Handling custom _id fields</a></h2><p>A discriminator&#39;s fields are the union of the base schema&#39;s fields and
-the discriminator schema&#39;s fields, and the discriminator schema&#39;s fields
-take precedence. There is one exception: the default <code>_id</code> field.</p>
-<p>You can work around this by setting the <code>_id</code> option to false in the
-discriminator schema as shown below.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> options = {discriminatorKey: <span class="hljs-string">'kind'</span>};
-
-<span class="hljs-comment">// Base schema has a String `_id` and a Date `time`...</span>
-<span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> mongoose.Schema({_id: <span class="hljs-built_in">String</span>, time: <span class="hljs-built_in">Date</span>},
-  options);
-<span class="hljs-keyword">var</span> Event = mongoose.model(<span class="hljs-string">'BaseEvent'</span>, eventSchema);
-
-<span class="hljs-keyword">var</span> clickedLinkSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  url: <span class="hljs-built_in">String</span>,
-  time: <span class="hljs-built_in">String</span>
-}, options);
-<span class="hljs-comment">// But the discriminator schema has a String `time`, and an implicitly added</span>
-<span class="hljs-comment">// ObjectId `_id`.</span>
-assert.ok(clickedLinkSchema.path(<span class="hljs-string">'_id'</span>));
-assert.equal(clickedLinkSchema.path(<span class="hljs-string">'_id'</span>).instance, <span class="hljs-string">'ObjectID'</span>);
-<span class="hljs-keyword">var</span> ClickedLinkEvent = Event.discriminator(<span class="hljs-string">'ChildEventBad'</span>,
-  clickedLinkSchema);
-
-<span class="hljs-keyword">var</span> event1 = <span class="hljs-keyword">new</span> ClickedLinkEvent({ _id: <span class="hljs-string">'custom id'</span>, time: <span class="hljs-string">'4pm'</span> });
-<span class="hljs-comment">// Woops, clickedLinkSchema overwrites the `time` path, but **not**</span>
-<span class="hljs-comment">// the `_id` path because that was implicitly added.</span>
-assert.ok(<span class="hljs-keyword">typeof</span> event1._id === <span class="hljs-string">'string'</span>);
-assert.ok(<span class="hljs-keyword">typeof</span> event1.time === <span class="hljs-string">'string'</span>);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Using discriminators with <code>Model.create()</code></a></h2><p>When you use <code>Model.create()</code>, mongoose will pull the correct type from
-the discriminator key for you.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Schema = mongoose.Schema;
-<span class="hljs-keyword">var</span> shapeSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>
-}, { discriminatorKey: <span class="hljs-string">'kind'</span> });
-
-<span class="hljs-keyword">var</span> Shape = db.model(<span class="hljs-string">'Shape'</span>, shapeSchema);
-
-<span class="hljs-keyword">var</span> Circle = Shape.discriminator(<span class="hljs-string">'Circle'</span>,
-  <span class="hljs-keyword">new</span> Schema({ radius: <span class="hljs-built_in">Number</span> }));
-<span class="hljs-keyword">var</span> Square = Shape.discriminator(<span class="hljs-string">'Square'</span>,
-  <span class="hljs-keyword">new</span> Schema({ side: <span class="hljs-built_in">Number</span> }));
-
-<span class="hljs-keyword">var</span> shapes = [
-  { name: <span class="hljs-string">'Test'</span> },
-  { kind: <span class="hljs-string">'Circle'</span>, radius: <span class="hljs-number">5</span> },
-  { kind: <span class="hljs-string">'Square'</span>, side: <span class="hljs-number">10</span> }
-];
-Shape.create(shapes, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, shapes</span>) </span>{
-  assert.ifError(error);
-  assert.ok(shapes[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> Shape);
-  assert.ok(shapes[<span class="hljs-number">1</span>] <span class="hljs-keyword">instanceof</span> Circle);
-  assert.equal(shapes[<span class="hljs-number">1</span>].radius, <span class="hljs-number">5</span>);
-  assert.ok(shapes[<span class="hljs-number">2</span>] <span class="hljs-keyword">instanceof</span> Square);
-  assert.equal(shapes[<span class="hljs-number">2</span>].side, <span class="hljs-number">10</span>);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Embedded discriminators in arrays</a></h2><p>You can also define discriminators on embedded document arrays.
-Embedded discriminators are different because the different discriminator
-types are stored in the same document array (within a document) rather
-than the same collection. In other words, embedded discriminators let
-you store subdocuments matching different schemas in the same array.</p>
-<p>As a general best practice, make sure you declare any hooks on your
-schemas <strong>before</strong> you use them. You should <strong>not</strong> call <code>pre()</code> or
-<code>post()</code> after calling <code>discriminator()</code></p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> Schema({ message: <span class="hljs-built_in">String</span> },
-  { discriminatorKey: <span class="hljs-string">'kind'</span>, _id: <span class="hljs-literal">false</span> });
-
-<span class="hljs-keyword">var</span> batchSchema = <span class="hljs-keyword">new</span> Schema({ events: [eventSchema] });
-
-<span class="hljs-comment">// `batchSchema.path('events')` gets the mongoose `DocumentArray`</span>
-<span class="hljs-keyword">var</span> docArray = batchSchema.path(<span class="hljs-string">'events'</span>);
-
-<span class="hljs-comment">// The `events` array can contain 2 different types of events, a</span>
-<span class="hljs-comment">// 'clicked' event that requires an element id that was clicked...</span>
-<span class="hljs-keyword">var</span> clickedSchema = <span class="hljs-keyword">new</span> Schema({
-  element: {
-    type: <span class="hljs-built_in">String</span>,
-    required: <span class="hljs-literal">true</span>
-  }
-}, { _id: <span class="hljs-literal">false</span> });
-<span class="hljs-comment">// Make sure to attach any hooks to `eventSchema` and `clickedSchema`</span>
-<span class="hljs-comment">// **before** calling `discriminator()`.</span>
-<span class="hljs-keyword">var</span> Clicked = docArray.discriminator(<span class="hljs-string">'Clicked'</span>, clickedSchema);
-
-<span class="hljs-comment">// ... and a 'purchased' event that requires the product that was purchased.</span>
-<span class="hljs-keyword">var</span> Purchased = docArray.discriminator(<span class="hljs-string">'Purchased'</span>, <span class="hljs-keyword">new</span> Schema({
-  product: {
-    type: <span class="hljs-built_in">String</span>,
-    required: <span class="hljs-literal">true</span>
-  }
-}, { _id: <span class="hljs-literal">false</span> }));
-
-<span class="hljs-keyword">var</span> Batch = db.model(<span class="hljs-string">'EventBatch'</span>, batchSchema);
-
-<span class="hljs-comment">// Create a new batch of events with different kinds</span>
-<span class="hljs-keyword">var</span> batch = {
-  events: [
-    { kind: <span class="hljs-string">'Clicked'</span>, element: <span class="hljs-string">'#hero'</span>, message: <span class="hljs-string">'hello'</span> },
-    { kind: <span class="hljs-string">'Purchased'</span>, product: <span class="hljs-string">'action-figure-1'</span>, message: <span class="hljs-string">'world'</span> }
-  ]
-};
-
-Batch.create(batch).
-  then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-    assert.equal(doc.events.length, <span class="hljs-number">2</span>);
-
-    assert.equal(doc.events[<span class="hljs-number">0</span>].element, <span class="hljs-string">'#hero'</span>);
-    assert.equal(doc.events[<span class="hljs-number">0</span>].message, <span class="hljs-string">'hello'</span>);
-    assert.ok(doc.events[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> Clicked);
-
-    assert.equal(doc.events[<span class="hljs-number">1</span>].product, <span class="hljs-string">'action-figure-1'</span>);
-    assert.equal(doc.events[<span class="hljs-number">1</span>].message, <span class="hljs-string">'world'</span>);
-    assert.ok(doc.events[<span class="hljs-number">1</span>] <span class="hljs-keyword">instanceof</span> Purchased);
-
-    doc.events.push({ kind: <span class="hljs-string">'Purchased'</span>, product: <span class="hljs-string">'action-figure-2'</span> });
-    <span class="hljs-keyword">return</span> doc.save();
-  }).
-  then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-    assert.equal(doc.events.length, <span class="hljs-number">3</span>);
-
-    assert.equal(doc.events[<span class="hljs-number">2</span>].product, <span class="hljs-string">'action-figure-2'</span>);
-    assert.ok(doc.events[<span class="hljs-number">2</span>] <span class="hljs-keyword">instanceof</span> Purchased);
-
-    done();
-  }).
-  <span class="hljs-keyword">catch</span>(done);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Recursive embedded discriminators in arrays</a></h2><p>You can also define embedded discriminators on embedded discriminators.
-In the below example, <code>sub_events</code> is an embedded discriminator, and
-for <code>sub_event</code> keys with value &#39;SubEvent&#39;, <code>sub_events.events</code> is an
-embedded discriminator.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> singleEventSchema = <span class="hljs-keyword">new</span> Schema({ message: <span class="hljs-built_in">String</span> },
-  { discriminatorKey: <span class="hljs-string">'kind'</span>, _id: <span class="hljs-literal">false</span> });
-
-<span class="hljs-keyword">var</span> eventListSchema = <span class="hljs-keyword">new</span> Schema({ events: [singleEventSchema] });
-
-<span class="hljs-keyword">var</span> subEventSchema = <span class="hljs-keyword">new</span> Schema({
-   sub_events: [singleEventSchema]
-}, { _id: <span class="hljs-literal">false</span> });
-
-<span class="hljs-keyword">var</span> SubEvent = subEventSchema.path(<span class="hljs-string">'sub_events'</span>).
-  discriminator(<span class="hljs-string">'SubEvent'</span>, subEventSchema);
-eventListSchema.path(<span class="hljs-string">'events'</span>).discriminator(<span class="hljs-string">'SubEvent'</span>, subEventSchema);
-
-<span class="hljs-keyword">var</span> Eventlist = db.model(<span class="hljs-string">'EventList'</span>, eventListSchema);
-
-<span class="hljs-comment">// Create a new batch of events with different kinds</span>
-<span class="hljs-keyword">var</span> list = {
-  events: [
-    { kind: <span class="hljs-string">'SubEvent'</span>, sub_events: [{kind:<span class="hljs-string">'SubEvent'</span>, sub_events:[], message:<span class="hljs-string">'test1'</span>}], message: <span class="hljs-string">'hello'</span> },
-    { kind: <span class="hljs-string">'SubEvent'</span>, sub_events: [{kind:<span class="hljs-string">'SubEvent'</span>, sub_events:[{kind:<span class="hljs-string">'SubEvent'</span>, sub_events:[], message:<span class="hljs-string">'test3'</span>}], message:<span class="hljs-string">'test2'</span>}], message: <span class="hljs-string">'world'</span> }
-  ]
-};
-
-Eventlist.create(list).
-  then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-    assert.equal(doc.events.length, <span class="hljs-number">2</span>);
-
-    assert.equal(doc.events[<span class="hljs-number">0</span>].sub_events[<span class="hljs-number">0</span>].message, <span class="hljs-string">'test1'</span>);
-    assert.equal(doc.events[<span class="hljs-number">0</span>].message, <span class="hljs-string">'hello'</span>);
-    assert.ok(doc.events[<span class="hljs-number">0</span>].sub_events[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> SubEvent);
-
-    assert.equal(doc.events[<span class="hljs-number">1</span>].sub_events[<span class="hljs-number">0</span>].sub_events[<span class="hljs-number">0</span>].message, <span class="hljs-string">'test3'</span>);
-    assert.equal(doc.events[<span class="hljs-number">1</span>].message, <span class="hljs-string">'world'</span>);
-    assert.ok(doc.events[<span class="hljs-number">1</span>].sub_events[<span class="hljs-number">0</span>].sub_events[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> SubEvent);
-
-    doc.events.push({kind:<span class="hljs-string">'SubEvent'</span>, sub_events:[{kind:<span class="hljs-string">'SubEvent'</span>, sub_events:[], message:<span class="hljs-string">'test4'</span>}], message:<span class="hljs-string">'pushed'</span>});
-    <span class="hljs-keyword">return</span> doc.save();
-  }).
-  then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-    assert.equal(doc.events.length, <span class="hljs-number">3</span>);
-
-    assert.equal(doc.events[<span class="hljs-number">2</span>].message, <span class="hljs-string">'pushed'</span>);
-    assert.ok(doc.events[<span class="hljs-number">2</span>].sub_events[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> SubEvent);
-
-    done();
-  }).
-  <span class="hljs-keyword">catch</span>(done);</code></pre>
-<div class="suffix"></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/documents.html b/docs/documents.html
deleted file mode 100644
index e21e36fbc7e..00000000000
--- a/docs/documents.html
+++ /dev/null
@@ -1,154 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Documents</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="documents">Documents</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Mongoose <a href="./api.html#document-js">documents</a> represent a one-to-one mapping
-to documents as stored in MongoDB. Each document is an instance of its
-<a href="./models.html">Model</a>.</p>
-<ul class="toc">
-  <li><a href="#documents-vs-models">Documents vs Models</a></li>
-  <li><a href="#retrieving">Retrieving</a></li>
-  <li><a href="#updating">Updating</a></li>
-  <li><a href="#validating">Validating</a></li>
-  <li><a href="#overwriting">Overwriting</a></li>
-</ul>
-
-<h3 id="documents-vs-models">Documents vs Models</h3>
-<p><a href="api.html#Document">Document</a> and <a href="api.html#Model">Model</a> are distinct
-classes in Mongoose. The Model class is a subclass of the Document class.
-When you use the <a href="api.html#Model">Model constructor</a>, you create a
-new document.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> MyModel();
-
-doc <span class="hljs-keyword">instanceof</span> MyModel; <span class="hljs-comment">// true</span>
-doc <span class="hljs-keyword">instanceof</span> mongoose.Model; <span class="hljs-comment">// true</span>
-doc <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// true</span></code></pre>
-<p>In Mongoose, a &quot;document&quot; generally means an instance of a model.
-You should not have to create an instance of the Document class without
-going through a model.</p>
-<h3 id="retrieving">Retrieving</h3>
-<p>When you load documents from MongoDB using model functions like <a href="api.html#model_Model.findOne"><code>findOne()</code></a>,
-you get a Mongoose document back.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> MyModel.findOne();
-
-doc <span class="hljs-keyword">instanceof</span> MyModel; <span class="hljs-comment">// true</span>
-doc <span class="hljs-keyword">instanceof</span> mongoose.Model; <span class="hljs-comment">// true</span>
-doc <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// true</span></code></pre>
-<h3 id="updating">Updating</h3>
-<p>Mongoose documents track changes. You can modify a document using vanilla
-JavaScript assignments and Mongoose will convert it into <a href="https://docs.mongodb.com/manual/reference/operator/update/">MongoDB update operators</a>.</p>
-<pre><code class="language-javascript">doc.name = <span class="hljs-string">'foo'</span>;
-
-<span class="hljs-comment">// Mongoose sends a `updateOne({ _id: doc._id }, { $set: { name: 'foo' } })`</span>
-<span class="hljs-comment">// to MongoDB.</span>
-<span class="hljs-keyword">await</span> doc.save();</code></pre>
-<p>If the document with the corresponding <code>_id</code> is not found, Mongoose will
-report a <code>DocumentNotFoundError</code>:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> MyModel.findOne();
-
-<span class="hljs-comment">// Delete the document so Mongoose won't be able to save changes</span>
-<span class="hljs-keyword">await</span> MyModel.deleteOne({ _id: doc._id });
-
-doc.name = <span class="hljs-string">'foo'</span>;
-<span class="hljs-keyword">await</span> doc.save(); <span class="hljs-comment">// Throws DocumentNotFoundError</span></code></pre>
-<p>The <a href="api.html#model_Model-save"><code>save()</code></a> function is generally the right
-way to update a document with Mongoose. With <code>save()</code>, you get full
-<a href="validation.html">validation</a> and <a href="middleware.html">middleware</a>.</p>
-<p>For cases when <code>save()</code> isn&#39;t flexible enough, Mongoose lets you create
-your own <a href="https://docs.mongodb.com/manual/reference/operator/update/">MongoDB updates</a>
-with casting, <a href="middleware.html#notes">middleware</a>, and <a href="validation.html#update-validators">limited validation</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Update all documents in the `mymodels` collection</span>
-<span class="hljs-keyword">await</span> MyModel.updateMany({}, { $set: { name: <span class="hljs-string">'foo'</span> } });</code></pre>
-<p><em>Note that <code>update()</code>, <code>updateMany()</code>, <code>findOneAndUpdate()</code>, etc. do <em>not</em>
-execute <code>save()</code> middleware. If you need save middleware and full validation,
-first query for the document and then <code>save()</code> it.</em></p>
-<h3 id="validating">Validating</h3>
-<p>Documents are casted validated before they are saved. Mongoose first casts
-values to the specified type and then validates them. Internally, Mongoose
-calls the document&#39;s <a href="api.html#document_Document-validate"><code>validate()</code> method</a>
-before saving.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, age: { type: <span class="hljs-built_in">Number</span>, min: <span class="hljs-number">0</span> } });
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, schema);
-
-<span class="hljs-keyword">let</span> p = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'foo'</span>, age: <span class="hljs-string">'bar'</span> });
-<span class="hljs-comment">// Cast to Number failed for value "bar" at path "age"</span>
-<span class="hljs-keyword">await</span> p.validate();
-
-<span class="hljs-keyword">let</span> p2 = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'foo'</span>, age: <span class="hljs-number">-1</span> });
-<span class="hljs-comment">// Path `age` (-1) is less than minimum allowed value (0).</span>
-<span class="hljs-keyword">await</span> p2.validate();</code></pre>
-<p>Mongoose also supports limited validation on updates using the <a href="validation.html#update-validators"><code>runValidators</code> option</a>.
-Mongoose casts parameters to query functions like <code>findOne()</code>, <code>updateOne()</code>
-by default. However, Mongoose does <em>not</em> run validation on query function
-parameters by default. You need to set <code>runValidators: true</code> for Mongoose
-to validate.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Cast to number failed for value "bar" at path "age"</span>
-<span class="hljs-keyword">await</span> Person.updateOne({}, { age: <span class="hljs-string">'bar'</span> });
-
-<span class="hljs-comment">// Path `age` (-1) is less than minimum allowed value (0).</span>
-<span class="hljs-keyword">await</span> Person.updateOne({}, { age: <span class="hljs-number">-1</span> }, { runValidators: <span class="hljs-literal">true</span> });</code></pre>
-<p>Read the <a href="./validation.html">validation</a> guide for more details.</p>
-<h3 id="next-up">Next Up</h3>
-<p>Now that we&#39;ve covered Documents, let&#39;s take a look at
-<a href="/docs/subdocs.html">Subdocuments</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/faq.html b/docs/faq.html
deleted file mode 100644
index 67cf803bf43..00000000000
--- a/docs/faq.html
+++ /dev/null
@@ -1,372 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: FAQ</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>hr {
-  display: block;
-  margin-top: 40px;
-  margin-bottom: 40px;
-  border: 0px;
-  height: 1px;
-  background-color: #232323;
-  width: 100%;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="faq">FAQ</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p><strong>Q</strong>. Why don&#39;t my changes to arrays get saved when I update an element
-directly?</p>
-<pre><code class="language-javascript">doc.array[<span class="hljs-number">3</span>] = <span class="hljs-string">'changed'</span>;
-doc.save();</code></pre>
-<p><strong>A</strong>. Mongoose doesn&#39;t create getters/setters for array indexes; without
-them mongoose never gets notified of the change and so doesn&#39;t know to
-persist the new value. The work-around is to use
-<a href="./api.html#types_array_MongooseArray.set">MongooseArray#set</a> available
-in <strong>Mongoose &gt;= 3.2.0</strong>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// 3.2.0</span>
-doc.array.set(<span class="hljs-number">3</span>, <span class="hljs-string">'changed'</span>);
-doc.save();
-
-<span class="hljs-comment">// if running a version less than 3.2.0, you must mark the array modified before saving.</span>
-doc.array[<span class="hljs-number">3</span>] = <span class="hljs-string">'changed'</span>;
-doc.markModified(<span class="hljs-string">'array'</span>);
-doc.save();</code></pre>
-<hr id="unique-doesnt-work" />
-
-<p><strong>Q</strong>. I declared a schema property as <code>unique</code> but I can still save
-duplicates. What gives?</p>
-<p><strong>A</strong>. Mongoose doesn&#39;t handle <code>unique</code> on its own: <code>{ name: { type: String, unique: true } }</code>
-is just a shorthand for creating a <a href="https://docs.mongodb.com/manual/core/index-unique/">MongoDB unique index on <code>name</code></a>.
-For example, if MongoDB doesn&#39;t already have a unique index on <code>name</code>, the below code will not error despite the fact that <code>unique</code> is true.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: { type: <span class="hljs-built_in">String</span>, unique: <span class="hljs-literal">true</span> }
-});
-<span class="hljs-keyword">var</span> Model = db.model(<span class="hljs-string">'Test'</span>, schema);
-
-Model.create([{ name: <span class="hljs-string">'Val'</span> }, { name: <span class="hljs-string">'Val'</span> }], <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(err); <span class="hljs-comment">// No error, unless index was already built</span>
-});</code></pre>
-<p>However, if you wait for the index to build using the <code>Model.on(&#39;index&#39;)</code> event, attempts to save duplicates will correctly error.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: { type: <span class="hljs-built_in">String</span>, unique: <span class="hljs-literal">true</span> }
-});
-<span class="hljs-keyword">var</span> Model = db.model(<span class="hljs-string">'Test'</span>, schema);
-
-Model.on(<span class="hljs-string">'index'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{ <span class="hljs-comment">// &lt;-- Wait for model's indexes to finish</span>
-  assert.ifError(err);
-  Model.create([{ name: <span class="hljs-string">'Val'</span> }, { name: <span class="hljs-string">'Val'</span> }], <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(err);
-  });
-});
-
-<span class="hljs-comment">// Promise based alternative. `init()` returns a promise that resolves</span>
-<span class="hljs-comment">// when the indexes have finished building successfully. The `init()`</span>
-<span class="hljs-comment">// function is idempotent, so don't worry about triggering an index rebuild.</span>
-Model.init().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  assert.ifError(err);
-  Model.create([{ name: <span class="hljs-string">'Val'</span> }, { name: <span class="hljs-string">'Val'</span> }], <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(err);
-  });
-});</code></pre>
-<p>MongoDB persists indexes, so you only need to rebuild indexes if you&#39;re starting
-with a fresh database or you ran <code>db.dropDatabase()</code>. In a production environment,
-you should <a href="https://docs.mongodb.com/manual/reference/method/db.collection.createIndex/">create your indexes using the MongoDB shell</a>
-rather than relying on mongoose to do it for you. The <code>unique</code> option for schemas is
-convenient for development and documentation, but mongoose is <em>not</em> an index management solution.</p>
-<hr id="nested-properties" />
-
-<p><strong>Q</strong>. When I have a nested property in a schema, mongoose adds empty objects by default. Why?</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  nested: {
-    prop: <span class="hljs-built_in">String</span>
-  }
-});
-<span class="hljs-keyword">var</span> Model = db.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-comment">// The below prints `{ _id: /* ... */, nested: {} }`, mongoose assigns</span>
-<span class="hljs-comment">// `nested` to an empty object `{}` by default.</span>
-<span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">new</span> Model());</code></pre>
-<p><strong>A</strong>. This is a performance optimization. These empty objects are not saved
-to the database, nor are they in the result <code>toObject()</code>, nor do they show
-up in <code>JSON.stringify()</code> output unless you turn off the <a href="./guide.html#minimize"><code>minimize</code> option</a>.</p>
-<p>The reason for this behavior is that Mongoose&#39;s change detection
-and getters/setters are based on <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty"><code>Object.defineProperty()</code></a>.
-In order to support change detection on nested properties without incurring
-the overhead of running <code>Object.defineProperty()</code> every time a document is created,
-mongoose defines properties on the <code>Model</code> prototype when the model is compiled.
-Because mongoose needs to define getters and setters for <code>nested.prop</code>, <code>nested</code>
-must always be defined as an object on a mongoose document, even if <code>nested</code>
-is undefined on the underlying <a href="./guide.html#minimize">POJO</a>.</p>
-<hr id="destructured-imports" />
-
-<p><strong>Q</strong>. When I use named imports like <code>import { set } from &#39;mongoose&#39;</code>, I
-get a <code>TypeError</code>. What causes this issue and how can I fix it?</p>
-<p><strong>A</strong>. The only import syntax Mongoose supports is <code>import mongoose from &#39;mongoose&#39;</code>.
-Syntaxes like <code>import * from &#39;mongoose&#39;</code> or <code>import { model } from &#39;mongoose&#39;</code> do <strong>not</strong> work.
-The global Mongoose object stores types, <a href="/docs/api.html#mongoose_Mongoose-set">global options</a>, and other important
-properties that Mongoose needs. When you do <code>import { model } from &#39;mongoose&#39;</code>, the
-<code>this</code> value in <code>model()</code> is not the Mongoose global.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// file1.js</span>
-exports.answer = <span class="hljs-number">42</span>;
-exports.foo = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>.answer); };
-
-<span class="hljs-comment">// file2.js</span>
-<span class="hljs-keyword">const</span> obj = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./file1'</span>);
-obj.foo(); <span class="hljs-comment">// "42"</span>
-
-<span class="hljs-comment">// file3.js</span>
-<span class="hljs-keyword">const</span> { foo } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./file1'</span>);
-foo(); <span class="hljs-comment">// "undefined"</span></code></pre>
-<hr id="arrow-functions" />
-
-<p><strong>Q</strong>. I&#39;m using an arrow function for a <a href="./guide.html#virtuals">virtual</a>, <a href="./middleware.html">middleware</a>, <a href="./api.html#schematype_SchemaType-get">getter</a>/<a href="./api.html#schematype_SchemaType-set">setter</a>, or <a href="./guide.html#methods">method</a> and the value of <code>this</code> is wrong.</p>
-<p><strong>A</strong>. Arrow functions <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this">handle the <code>this</code> keyword much differently than conventional functions</a>.
-Mongoose getters/setters depend on <code>this</code> to give you access to the document that you&#39;re writing to, but this functionality does not work with arrow functions. Do <strong>not</strong> use arrow functions for mongoose getters/setters unless do not intend to access the document in the getter/setter.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Do **NOT** use arrow functions as shown below unless you're certain</span>
-<span class="hljs-comment">// that's what you want. If you're reading this FAQ, odds are you should</span>
-<span class="hljs-comment">// just be using a conventional function.</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  propWithGetter: {
-    type: <span class="hljs-built_in">String</span>,
-    get: v =&gt; {
-      <span class="hljs-comment">// Will **not** be the doc, do **not** use arrow functions for getters/setters</span>
-      <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>);
-      <span class="hljs-keyword">return</span> v;
-    }
-  }
-});
-
-<span class="hljs-comment">// `this` will **not** be the doc, do **not** use arrow functions for methods</span>
-schema.method.arrowMethod = () =&gt; <span class="hljs-keyword">this</span>;
-schema.virtual(<span class="hljs-string">'virtualWithArrow'</span>).get(() =&gt; {
-  <span class="hljs-comment">// `this` will **not** be the doc, do **not** use arrow functions for virtuals</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span>);
-});</code></pre>
-<hr id="type-key">
-
-<p><strong>Q</strong>. I have an embedded property named <code>type</code> like this:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> holdingSchema = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// You might expect `asset` to be an object that has 2 properties,</span>
-  <span class="hljs-comment">// but unfortunately `type` is special in mongoose so mongoose</span>
-  <span class="hljs-comment">// interprets this schema to mean that `asset` is a string</span>
-  asset: {
-    type: <span class="hljs-built_in">String</span>,
-    ticker: <span class="hljs-built_in">String</span>
-  }
-});</code></pre>
-<p>But mongoose gives me a CastError telling me that it can&#39;t cast an object
-to a string when I try to save a <code>Holding</code> with an <code>asset</code> object. Why
-is this?</p>
-<pre><code class="language-javascript">Holding.create({ asset: { type: <span class="hljs-string">'stock'</span>, ticker: <span class="hljs-string">'MDB'</span> } }).catch(error =&gt; {
-  <span class="hljs-comment">// Cast to String failed for value "{ type: 'stock', ticker: 'MDB' }" at path "asset"</span>
-  <span class="hljs-built_in">console</span>.error(error);
-});</code></pre>
-<p><strong>A</strong>. The <code>type</code> property is special in mongoose, so when you say
-<code>type: String</code>, mongoose interprets it as a type declaration. In the
-above schema, mongoose thinks <code>asset</code> is a string, not an object. Do
-this instead:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> holdingSchema = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// This is how you tell mongoose you mean `asset` is an object with</span>
-  <span class="hljs-comment">// a string property `type`, as opposed to telling mongoose that `asset`</span>
-  <span class="hljs-comment">// is a string.</span>
-  asset: {
-    type: { type: <span class="hljs-built_in">String</span> },
-    ticker: <span class="hljs-built_in">String</span>
-  }
-});</code></pre>
-<hr id="populate_sort_order" />
-
-<p><strong>Q</strong>. I&#39;m populating a nested property under an array like the below code:</p>
-<pre><code class="language-javascript">  <span class="hljs-keyword">new</span> Schema({
-    arr: [{
-      child: { ref: <span class="hljs-string">'OtherModel'</span>, type: Schema.Types.ObjectId }
-    }]
-  });</code></pre>
-<p><code>.populate({ path: &#39;arr.child&#39;, options: { sort: &#39;name&#39; } })</code> won&#39;t sort
-by <code>arr.child.name</code>?</p>
-<p><strong>A</strong>. See <a href="https://github.com/Automattic/mongoose/issues/2202">this GitHub issue</a>. It&#39;s a known issue but one that&#39;s exceptionally difficult to fix.</p>
-<hr id="model_functions_hanging" />
-
-<p><strong>Q</strong>. All function calls on my models hang, what am I doing wrong?</p>
-<p><strong>A</strong>. By default, mongoose will buffer your function calls until it can
-connect to MongoDB. Read the <a href="./connections.html#buffering">buffering section of the connection docs</a>
-for more information.</p>
-<hr id="enable_debugging" />
-
-<p><strong>Q</strong>. How can I enable debugging?</p>
-<p><strong>A</strong>. Set the <code>debug</code> option to <code>true</code>:</p>
-<pre><code class="language-javascript">mongoose.set(<span class="hljs-string">'debug'</span>, <span class="hljs-literal">true</span>)</code></pre>
-<p>All executed collection methods will log output of their arguments to your
-console.</p>
-<hr id="callback_never_executes" />
-
-<p><strong>Q</strong>. My <code>save()</code> callback never executes. What am I doing wrong?</p>
-<p><strong>A</strong>. All <code>collection</code> actions (insert, remove, queries, etc.) are queued
-until the <code>connection</code> opens. It is likely that an error occurred while
-attempting to connect. Try adding an error handler to your connection.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// if connecting on the default mongoose connection</span>
-mongoose.connect(..);
-mongoose.connection.on(<span class="hljs-string">'error'</span>, handleError);
-
-<span class="hljs-comment">// if connecting on a separate connection</span>
-<span class="hljs-keyword">var</span> conn = mongoose.createConnection(..);
-conn.on(<span class="hljs-string">'error'</span>, handleError);</code></pre>
-<p>If you want to opt out of mongoose&#39;s buffering mechanism across your entire
-application, set the global <code>bufferCommands</code> option to false:</p>
-<pre><code class="language-javascript">mongoose.set(<span class="hljs-string">'bufferCommands'</span>, <span class="hljs-literal">false</span>);</code></pre>
-<hr id="creating_connections" />
-
-<p><strong>Q</strong>. Should I create/destroy a new connection for each database operation?</p>
-<p><strong>A</strong>. No. Open your connection when your application starts up and leave
-it open until the application shuts down.</p>
-<hr id="overwrite-model-error" />
-
-<p><strong>Q</strong>. Why do I get &quot;OverwriteModelError: Cannot overwrite .. model once
-compiled&quot; when I use nodemon / a testing framework?</p>
-<p><strong>A</strong>. <code>mongoose.model(&#39;ModelName&#39;, schema)</code> requires &#39;ModelName&#39; to be
-unique, so you can access the model by using <code>mongoose.model(&#39;ModelName&#39;)</code>.
-If you put <code>mongoose.model(&#39;ModelName&#39;, schema);</code> in a
-<a href="https://mochajs.org/#hooks">mocha <code>beforeEach()</code> hook</a>, this code will
-attempt to create a new model named &#39;ModelName&#39; before <strong>every</strong> test,
-and so you will get an error. Make sure you only create a new model with
-a given name <strong>once</strong>. If you need to create multiple models with the
-same name, create a new connection and bind the model to the connection.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> connection = mongoose.createConnection(..);
-
-<span class="hljs-comment">// use mongoose.Schema</span>
-<span class="hljs-keyword">var</span> kittySchema = mongoose.Schema({ name: <span class="hljs-built_in">String</span> });
-
-<span class="hljs-comment">// use connection.model</span>
-<span class="hljs-keyword">var</span> Kitten = connection.model(<span class="hljs-string">'Kitten'</span>, kittySchema);</code></pre>
-<hr id="array-defaults" />
-
-<p><strong>Q</strong>. How can I change mongoose&#39;s default behavior of initializing an array
-path to an empty array so that I can require real data on document creation?</p>
-<p><strong>A</strong>. You can set the default of the array to a function that returns <code>undefined</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> CollectionSchema = <span class="hljs-keyword">new</span> Schema({
-  field1: {
-    type: [<span class="hljs-built_in">String</span>],
-    <span class="hljs-keyword">default</span>: <span class="hljs-keyword">void</span> <span class="hljs-number">0</span>
-  }
-});</code></pre>
-<p><strong>Q</strong>. How can I initialize an array path to <code>null</code>?</p>
-<p><strong>A</strong>. You can set the default of the array to a function that returns <code>null</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> CollectionSchema = <span class="hljs-keyword">new</span> Schema({
-  field1: {
-    type: [<span class="hljs-built_in">String</span>],
-    <span class="hljs-keyword">default</span>: () =&gt; { <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>; }
-  }
-});</code></pre>
-<hr id="aggregate-casting" />
-
-<p><strong>Q</strong>. Why does my aggregate $match fail to return the document that my find query
-returns when working with dates?</p>
-<p><strong>A</strong>. Mongoose does not cast aggregation pipeline stages because with $project,
-$group, etc. the type of a property may change during the aggregation. If you want
-to query by date using the aggregation framework, you&#39;re responsible for ensuring
-that you&#39;re passing in a valid date.</p>
-<hr id="date_changes" />
-
-<p><strong>Q</strong>. Why don&#39;t in-place modifications to date objects
-(e.g. <code>date.setMonth(1);</code>) get saved?</p>
-<pre><code class="language-javascript">doc.createdAt.setDate(<span class="hljs-number">2011</span>, <span class="hljs-number">5</span>, <span class="hljs-number">1</span>);
-doc.save(); <span class="hljs-comment">// createdAt changes won't get saved!</span></code></pre>
-<p><strong>A</strong>. Mongoose currently doesn&#39;t watch for in-place updates to date
-objects. If you have need for this feature, feel free to discuss on
-<a href="https://github.com/Automattic/mongoose/issues/3738">this GitHub issue</a>.
-There are several workarounds:</p>
-<pre><code class="language-javascript">doc.createdAt.setDate(<span class="hljs-number">2011</span>, <span class="hljs-number">5</span>, <span class="hljs-number">1</span>);
-doc.markModified(<span class="hljs-string">'createdAt'</span>);
-doc.save(); <span class="hljs-comment">// Works</span>
-
-doc.createdAt = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-number">2011</span>, <span class="hljs-number">5</span>, <span class="hljs-number">1</span>).setHours(<span class="hljs-number">4</span>);
-doc.save(); <span class="hljs-comment">// Works</span></code></pre>
-<hr id="parallel_saves" />
-
-<p><strong>Q</strong>. Why does calling <code>save()</code> multiple times on the same document in parallel only let
-the first save call succeed and return ParallelSaveErrors for the rest?</p>
-<p><strong>A</strong>. Due to the asynchronous nature of validation and middleware in general, calling
-<code>save()</code> multiple times in parallel on the same doc could result in conflicts. For example,
-validating, and then subsequently invalidating the same path.</p>
-<hr id="objectid-validation" />
-
-<p><strong>Q</strong>. Why is <strong>any</strong> 12 character string successfully cast to an ObjectId?</p>
-<p><strong>A</strong>. Technically, any 12 character string is a valid <a href="https://docs.mongodb.com/manual/reference/bson-types/#objectid">ObjectId</a>.
-Consider using a regex like <code>/^[a-f0-9]{24}$/</code> to test whether a string is exactly 24 hex characters.</p>
-<hr id="slow-localhost" />
-
-<p><strong>Q</strong>. I&#39;m connecting to <code>localhost</code> and it takes me nearly 1 second to connect. How do I fix this?</p>
-<p><strong>A</strong>. The underlying MongoDB driver defaults to looking for IPv6 addresses, so the most likely cause is that your <code>localhost</code> DNS mapping isn&#39;t configured to handle IPv6. Use <code>127.0.0.1</code> instead of <code>localhost</code> or use the <code>family</code> option as shown in the <a href="https://mongoosejs.com/docs/connections.html#options">connection docs</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// One alternative is to bypass 'localhost'</span>
-mongoose.connect(<span class="hljs-string">'mongodb://127.0.0.1:27017/test'</span>);
-<span class="hljs-comment">// Another option is to specify the `family` option, which tells the</span>
-<span class="hljs-comment">// MongoDB driver to only look for IPv4 addresses rather than IPv6 first.</span>
-mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/test'</span>, { family: <span class="hljs-number">4</span> });</code></pre>
-<hr id="map-keys-strings" />
-
-<p><strong>Q</strong>. Why do keys in Mongoose Maps have to be strings?</p>
-<p><strong>A</strong>. Because the Map eventually gets stored in MongoDB where the keys must be strings.</p>
-<hr id="add_something" />
-
-<p><strong>Something to add?</strong></p>
-<p>If you&#39;d like to contribute to this page, please
-<a href="https://github.com/Automattic/mongoose/tree/master/docs/faq.jade">visit it</a>
-on github and use the <a href="https://github.com/blog/844-forking-with-the-edit-button">Edit</a> button to send a pull request.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/further_reading.html b/docs/further_reading.html
deleted file mode 100644
index c252233964b..00000000000
--- a/docs/further_reading.html
+++ /dev/null
@@ -1,248 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Further Reading</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>img { width: auto; }
-
-.pluralsight-link {
-  float: left;
-  margin-right: 0.5em;
-}
-
-.pluralsight-title {
-  font-size: 1.5em;
-}
-
-p {
-  line-height: 1.5em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="further-reading">Further Reading</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>There&#39;s a lot of great content out there to learn more about Mongoose.
-This page has a list of video courses, books, and blog posts curated by
-Mongoose maintainers. We&#39;ve gone through every course, book, and article
-on this page to make sure it is high quality.</p>
-<ul>
-<li><a href="#video-courses">Video Courses</a></li>
-<li><a href="#books">Books</a></li>
-<li><a href="#blog-posts">Blog Posts</a></li>
-</ul>
-<h2 id="video-courses">Video Courses</h2>
-<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-</a>
-<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fapi-design-nodejs-express-mongo%2Ftable-of-contents">
-  API Design in Node.js Featuring Express & Mongo
-</a>
-
-<p>This course is a great introduction to building a RESTful API with <a href="http://expressjs.com/">Express</a>
-and Mongoose. The instructor is <a href="https://frontendmasters.com/teachers/scott-moss/">Scott Moss</a>,
-a serial entrepreneur and former intructor at <a href="https://www.hackreactor.com/">Hack Reactor</a>, San Francisco&#39;s number one coding bootcamp.</p>
-<div style="clear: both"></div>
-<br><br>
-
-<a href="https://thinkster.io/tutorials/node-json-api" class="pluralsight-link" style="padding:20px">
-  <img src="https://pbs.twimg.com/profile_images/819400302864412676/6x2g2XtJ_400x400.jpg" border="0" alt="" style="width: 140px" />
-</a>
-
-<a class="pluralsight-title" href="https://thinkster.io/tutorials/node-json-api">
-  Building a Production Ready Node.js JSON API
-</a>
-
-<p><br><br></p>
-<p><a href="https://thinkster.io/">Thinkster</a> has created a full stack web
-development course for just about every backend and frontend framework
-you can think of. Want to learn how to build a full stack app with Vue
-and Django, or with Angular and Rails? Thinkster has a course for that.
-The Node.js tutorial walks you through building a production-ready
-RESTful API with Express and Mongoose from scratch.</p>
-<div style="clear: both"></div>
-<br><br>
-
-<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-</a>
-<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoose-for-nodejs-mongodb%2Ftable-of-contents">
-  Introduction to Mongoose for Node.js and MongoDB
-</a>
-
-<p><br><br></p>
-<p>Know someone who wants to get started building Node.js apps but doesn&#39;t have
-a lot of software development experience?
-This course is more beginner-friendly than <em>API Design</em> and is a great
-resource for beginners looking to get started.</p>
-<div style="clear: both"></div>
-<br><br>
-
-<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-</a>
-<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">
-  RESTful Web Services with Node.js and Express
-</a>
-
-<p><br><br></p>
-<p>Looking for a course to take you from zero to Express + Mongoose
-REST API fast? This is the one. This course is halfway
-between <em>API Design</em> and <em>Introduction to Mongoose</em>. It focuses more on
-<a href="http://expressjs.com/">Express</a>, but also doesn&#39;t go into as much detail as <em>API Design</em>. </p>
-<div style="clear: both"></div>
-<br><br>
-
-<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-</a>
-<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fbuilding-business-applications-vuejs%2Ftable-of-contents">
-  Building Business Applications with Vue.js and MongoDB
-</a>
-
-<p><br><br></p>
-<p>This course walks you through building a full-stack web application using
-the <a href="https://medium.com/@audretschjames/venom-stack-docker-setup-for-local-development-457093761ad1">VENoM Stack</a>.
-Try this course if you&#39;re a <a href="https://vuejs.org/">Vue.js</a> expert looking to
-expand into backend engineering or an experienced MongoDB dev looking to
-learn about frontend dev.</p>
-<div style="clear: both"></div>
-<br><br>
-
-<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-</a>
-<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoosejs-moving-forward%2Ftable-of-contents">
-  Moving Forward with Mongoose.js
-</a>
-
-<p><br><br></p>
-<p>Stuck maintaining a legacy codebase on Mongoose 3.x? This course will
-give you a detailed overview of the <a href="https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes">breaking changes and new features in Mongoose 4.x</a>,
-so you can upgrade with confidence.</p>
-<div style="clear: both"></div>
-
-<h2 id="books">Books</h2>
-<a class="pluralsight-link" href="http://bit.ly/mongoose-book-2013">
-  <img src="https://s3.amazonaws.com/codebarbarian-images/mongoose.jpg" style="width: 180px">
-</a>
-
-<a class="pluralsight-title" href="http://bit.ly/mongoose-book-2013">
-  <i>Mongoose for Application Development</i> by Simon Holmes
-</a>
-
-<p>This is the book on Mongoose. Even though it is from 2013,
-<em>Mongoose for Application Development</em> has stood the test of time. This
-book does an excellent job summarizing the core ideas that make Mongoose so
-powerful. Just sub out callbacks for promises.</p>
-<div style="clear: both"></div>
-
-<a class="pluralsight-link" href="https://bit.ly/mongodb-schema-design">
-  <img src="https://s3.amazonaws.com/codebarbarian-images/schemadesign.jpg" style="width: 180px">
-</a>
-
-<a class="pluralsight-title" href="https://bit.ly/mongodb-schema-design">
-  <i>The Little MongoDB Schema Design Book</i> by Christian Kvalheim
-</a>
-
-<p>Christian Kvalheim originally wrote the MongoDB Node.js driver in early 2010,
-and maintained the driver almost singlehandedly until 2017. As maintainer
-of the Node.js driver, Christian saw more Node.js+MongoDB code bases than
-anyone, and his experience is unmatched.
-This book distills 6 years of hard-learned lessons into concrete examples
-of how to design MongoDB schemas for massive scale. If you want to learn
-how to structure MongoDB schemas for an ecommerce store, a category tree, or a
-blog that can support hundreds of millions of requests per day, this is
-the book for you.</p>
-<div style="clear: both"></div>
-
-<h2 id="blog-posts">Blog Posts</h2>
-<a class="pluralsight-link" style="padding: 20px" href="https://medium.freecodecamp.org/introduction-to-mongoose-for-mongodb-d2a7aa593c57">
-  <img src="https://cdn-images-1.medium.com/max/800/1*uTZXsVta4TwghNobMkZeZg.png" style="width: 140px">
-</a>
-
-<a class="pluralsight-title" href="https://medium.freecodecamp.org/introduction-to-mongoose-for-mongodb-d2a7aa593c57">
-  <i>Introduction to Mongoose for MongoDB</i> on freeCodeCamp
-</a>
-
-<p>Coming from an SQL background and having trouble understanding Mongoose and MongoDB?
-This article explains the core concepts of Mongoose with references to similar
-concepts in SQL.</p>
-<div style="clear: both"></div>
-
-<a class="pluralsight-link" style="padding: 20px" href="https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/mongoose">
-  <img src="https://developer.mozilla.org/static/img/opengraph-logo.72382e605ce3.png" style="width: 140px">
-</a>
-
-<a class="pluralsight-title" href="https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/mongoose">
-  <i>Express Tutorial Part 3: Using a Database (with Mongoose)</i> on Mozilla Developer Network
-</a>
-
-<p>Virtually every JavaScript developer has read MDN docs. They&#39;re usually one
-of the top 3 results when you Google &quot;javascript startswith&quot; or any other
-core JavaScript function. This tutorial provides an overview of Mongoose
-in MDN&#39;s standard style and tone.</p>
-<div style="clear: both"></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/geojson.html b/docs/geojson.html
deleted file mode 100644
index 98835c183b2..00000000000
--- a/docs/geojson.html
+++ /dev/null
@@ -1,188 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Using GeoJSON</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="using-geojson">Using GeoJSON</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p><a href="http://geojson.org/">GeoJSON</a> is a format for storing geographic points and
-polygons. <a href="http://thecodebarbarian.com/80-20-guide-to-mongodb-geospatial-queries">MongoDB has excellent support for geospatial queries</a>
-on GeoJSON objects. Let&#39;s take a look at how you can use Mongoose to store
-and query GeoJSON objects.</p>
-<h2 id="points">Point Schema</h2>
-
-<p>The most simple structure in GeoJSON is a point. Below is an example point
-representing the approximate location of <a href="https://www.google.com/maps/@37.7,-122.5,9z">San Francisco</a>.
-Note that longitude comes first in a GeoJSON coordinate array, <strong>not</strong> latitude.</p>
-<pre><code>{
-  <span class="hljs-string">"type"</span> : <span class="hljs-string">"Point"</span>,
-  <span class="hljs-string">"coordinates"</span> : [
-    <span class="hljs-number">-122.5</span>,
-    <span class="hljs-number">37.7</span>
-  ]
-}</code></pre><p>Below is an example of a Mongoose schema where <code>location</code> is a point.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> citySchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  location: {
-    type: {
-      type: <span class="hljs-built_in">String</span>, <span class="hljs-comment">// Don't do `{ location: { type: String } }`</span>
-      enum: [<span class="hljs-string">'Point'</span>], <span class="hljs-comment">// 'location.type' must be 'Point'</span>
-      required: <span class="hljs-literal">true</span>
-    },
-    coordinates: {
-      type: [<span class="hljs-built_in">Number</span>],
-      required: <span class="hljs-literal">true</span>
-    }
-  }
-});</code></pre>
-<p>Using <a href="/docs/subdocs.html">subdocuments</a>, you can define a common <code>pointSchema</code> and reuse it everywhere you want to store a GeoJSON point.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> pointSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  type: {
-    type: <span class="hljs-built_in">String</span>,
-    enum: [<span class="hljs-string">'Point'</span>],
-    required: <span class="hljs-literal">true</span>
-  },
-  coordinates: {
-    type: [<span class="hljs-built_in">Number</span>],
-    required: <span class="hljs-literal">true</span>
-  }
-});
-
-<span class="hljs-keyword">const</span> citySchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  location: {
-    type: pointSchema,
-    required: <span class="hljs-literal">true</span>
-  }
-});</code></pre>
-<h2 id="polygons">Polygon Schema</h2>
-
-<p>GeoJSON polygons let you define an arbitrary shape on a map. For example,
-the below polygon is a GeoJSON rectangle that approximates the border
-of the state of Colorado.</p>
-<pre><code>{
-  <span class="hljs-string">"type"</span>: <span class="hljs-string">"Polygon"</span>,
-  <span class="hljs-string">"coordinates"</span>: [[
-    [<span class="hljs-number">-109</span>, <span class="hljs-number">41</span>],
-    [<span class="hljs-number">-102</span>, <span class="hljs-number">41</span>],
-    [<span class="hljs-number">-102</span>, <span class="hljs-number">37</span>],
-    [<span class="hljs-number">-109</span>, <span class="hljs-number">37</span>],
-    [<span class="hljs-number">-109</span>, <span class="hljs-number">41</span>]
-  ]]
-}</code></pre><p>Polygons are tricky because they use triple nested arrays. Below is
-how you create a Mongoose schema where <code>coordinates</code> is a triple nested
-array of numbers.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> polygonSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  type: {
-    type: <span class="hljs-built_in">String</span>,
-    enum: [<span class="hljs-string">'Polygon'</span>],
-    required: <span class="hljs-literal">true</span>
-  },
-  coordinates: {
-    type: [[[<span class="hljs-built_in">Number</span>]]], <span class="hljs-comment">// Array of arrays of arrays of numbers</span>
-    required: <span class="hljs-literal">true</span>
-  }
-});
-
-<span class="hljs-keyword">const</span> citySchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  location: polygonSchema
-});</code></pre>
-<h2 id="querying">Geospatial Queries with Mongoose</h2>
-
-<p>Mongoose queries support the same <a href="http://thecodebarbarian.com/80-20-guide-to-mongodb-geospatial-queries">geospatial query operators</a>
-that the MongoDB driver does. For example, the below script saves a
-<code>city</code> document those <code>location</code> property is a GeoJSON point representing
-the city of Denver, Colorado. It then queries for all documents within
-a polygon representing the state of Colorado using
-<a href="https://docs.mongodb.com/manual/reference/operator/query/geoWithin/">the MongoDB <code>$geoWithin</code> operator</a>.</p>
-<img src="https://i.imgur.com/i32pWnC.png">
-
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> City = db.model(<span class="hljs-string">'City'</span>, <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  location: pointSchema
-}));
-
-<span class="hljs-keyword">const</span> colorado = {
-  type: <span class="hljs-string">'Polygon'</span>,
-  coordinates: [[
-    [<span class="hljs-number">-109</span>, <span class="hljs-number">41</span>],
-    [<span class="hljs-number">-102</span>, <span class="hljs-number">41</span>],
-    [<span class="hljs-number">-102</span>, <span class="hljs-number">37</span>],
-    [<span class="hljs-number">-109</span>, <span class="hljs-number">37</span>],
-    [<span class="hljs-number">-109</span>, <span class="hljs-number">41</span>]
-  ]]
-};
-<span class="hljs-keyword">const</span> denver = { type: <span class="hljs-string">'Point'</span>, coordinates: [<span class="hljs-number">-104.9903</span>, <span class="hljs-number">39.7392</span>] };
-<span class="hljs-keyword">return</span> City.create({ name: <span class="hljs-string">'Denver'</span>, location: denver }).
-  then(() =&gt; City.findOne({
-    location: {
-      $geoWithin: {
-        $geometry: colorado
-      }
-    }
-  })).
-  then(doc =&gt; assert.equal(doc.name, <span class="hljs-string">'Denver'</span>));</code></pre>
-<p>Mongoose also has a <a href="/docs/api.html#query_Query-within"><code>within()</code> helper</a>
-that&#39;s a shorthand for <code>$geoWithin</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> denver = { type: <span class="hljs-string">'Point'</span>, coordinates: [<span class="hljs-number">-104.9903</span>, <span class="hljs-number">39.7392</span>] };
-<span class="hljs-keyword">return</span> City.create({ name: <span class="hljs-string">'Denver'</span>, location: denver }).
-  then(() =&gt; City.findOne().where(<span class="hljs-string">'location'</span>).within(colorado)).
-  then(doc =&gt; assert.equal(doc.name, <span class="hljs-string">'Denver'</span>));</code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/guide.html b/docs/guide.html
deleted file mode 100644
index b5f153ffb27..00000000000
--- a/docs/guide.html
+++ /dev/null
@@ -1,900 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Schemas</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="schemas">Schemas</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-<div class="important"><p>If you haven&#39;t yet done so, please take a minute to read the <a href="./index.html">quickstart</a> to get an idea of how Mongoose works.
-If you are migrating from 4.x to 5.x please take a moment to read the <a href="/docs/migrating_to_5.html">migration guide</a>.</p>
-</div><ul class="toc">
-  <li><a href="#models">Defining your schema</a></li>
-  <li><a href="#models">Creating a model</a></li>
-  <li><a href="#methods">Instance methods</a></li>
-  <li><a href="#statics">Statics</a></li>
-  <li><a href="#query-helpers">Query Helpers</a></li>
-  <li><a href="#indexes">Indexes</a></li>
-  <li><a href="#virtuals">Virtuals</a></li>
-  <li><a href="#aliases">Aliases</a></li>
-  <li><a href="#options">Options</a></li>
-  <li><a href="#plugins">Pluggable</a></li>
-</ul>
-
-<h3 id="definition"><a href="#definition">Defining your schema</a></h3>
-
-<p>Everything in Mongoose starts with a Schema. Each schema maps to a MongoDB
-collection and defines the shape of the documents within that collection.</p>
-<pre><code class="language-javascript">  <span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-  <span class="hljs-keyword">var</span> Schema = mongoose.Schema;
-
-  <span class="hljs-keyword">var</span> blogSchema = <span class="hljs-keyword">new</span> Schema({
-    title:  <span class="hljs-built_in">String</span>,
-    author: <span class="hljs-built_in">String</span>,
-    body:   <span class="hljs-built_in">String</span>,
-    comments: [{ body: <span class="hljs-built_in">String</span>, date: <span class="hljs-built_in">Date</span> }],
-    date: { type: <span class="hljs-built_in">Date</span>, <span class="hljs-keyword">default</span>: <span class="hljs-built_in">Date</span>.now },
-    hidden: <span class="hljs-built_in">Boolean</span>,
-    meta: {
-      votes: <span class="hljs-built_in">Number</span>,
-      favs:  <span class="hljs-built_in">Number</span>
-    }
-  });</code></pre>
-<p>If you want to add additional keys later, use the
-<a href="./api.html#schema_Schema-add">Schema#add</a> method.</p>
-<p>Each key in our code <code>blogSchema</code> defines a property in our documents which
-will be cast to its associated <a href="./api.html#schematype_SchemaType">SchemaType</a>.
-For example, we&#39;ve defined a property <code>title</code> which will be cast to the
-<a href="./api.html#schema-string-js">String</a> SchemaType and property <code>date</code>
-which will be cast to a <code>Date</code> SchemaType. Keys may also be assigned
-nested objects containing further key/type definitions like
-the <code>meta</code> property above.</p>
-<p>The permitted SchemaTypes are:</p>
-<ul>
-<li><a href="./schematypes.html#strings">String</a></li>
-<li><a href="./schematypes.html#numbers">Number</a></li>
-<li><a href="./schematypes.html#dates">Date</a></li>
-<li><a href="./schematypes.html#buffers">Buffer</a></li>
-<li><a href="./schematypes.html#booleans">Boolean</a></li>
-<li><a href="./schematypes.html#mixed">Mixed</a></li>
-<li><a href="./schematypes.html#objectids">ObjectId</a></li>
-<li><a href="./schematypes.html#arrays">Array</a></li>
-<li>Decimal128</li>
-<li><a href="./schematypes.html#maps">Map</a></li>
-</ul>
-<p>Read more about <a href="./schematypes.html">SchemaTypes here</a>.</p>
-<p>Schemas not only define the structure of your document and casting of
-properties, they also define document <a href="#methods">instance methods</a>,
-<a href="#statics">static Model methods</a>, <a href="#indexes">compound indexes</a>,
-and document lifecycle hooks called <a href="./middleware.html">middleware</a>.</p>
-<h3 id="models"><a href="#models">Creating a model</a></h3>
-
-<p>To use our schema definition, we need to convert our <code>blogSchema</code> into a
-<a href="./models.html">Model</a> we can work with.
-To do so, we pass it into <code>mongoose.model(modelName, schema)</code>:</p>
-<pre><code class="language-javascript">  <span class="hljs-keyword">var</span> Blog = mongoose.model(<span class="hljs-string">'Blog'</span>, blogSchema);
-  <span class="hljs-comment">// ready to go!</span></code></pre>
-<h3 id="methods"><a href="#methods">Instance methods</a></h3>
-
-<p>Instances of <code>Models</code> are <a href="./documents.html">documents</a>. Documents have
-many of their own <a href="./api.html#document-js">built-in instance methods</a>.
-We may also define our own custom document instance methods too.</p>
-<pre><code class="language-javascript">  <span class="hljs-comment">// define a schema</span>
-  <span class="hljs-keyword">var</span> animalSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, type: <span class="hljs-built_in">String</span> });
-
-  <span class="hljs-comment">// assign a function to the "methods" object of our animalSchema</span>
-  animalSchema.methods.findSimilarTypes = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">cb</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.model(<span class="hljs-string">'Animal'</span>).find({ type: <span class="hljs-keyword">this</span>.type }, cb);
-  };</code></pre>
-<p>Now all of our <code>animal</code> instances have a <code>findSimilarTypes</code> method available
-to them.</p>
-<pre><code class="language-javascript">  <span class="hljs-keyword">var</span> Animal = mongoose.model(<span class="hljs-string">'Animal'</span>, animalSchema);
-  <span class="hljs-keyword">var</span> dog = <span class="hljs-keyword">new</span> Animal({ type: <span class="hljs-string">'dog'</span> });
-
-  dog.findSimilarTypes(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, dogs</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(dogs); <span class="hljs-comment">// woof</span>
-  });</code></pre>
-<ul>
-<li>Overwriting a default mongoose document method may lead to unpredictable results. See <a href="./api.html#schema_Schema.reserved">this</a> for more details.</li>
-<li>The example above uses the <code>Schema.methods</code> object directly to save an instance method. You can also use the <code>Schema.method()</code> helper as described <a href="./api.html#schema_Schema-method">here</a>.</li>
-<li>Do <strong>not</strong> declare methods using ES6 arrow functions (<code>=&gt;</code>). Arrow functions <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this">explicitly prevent binding <code>this</code></a>, so your method will <strong>not</strong> have access to the document and the above examples will not work.</li>
-</ul>
-<h3 id="statics"><a href="#statics">Statics</a></h3>
-
-<p>You can also add static functions to your model. There are 2 equivalent
-ways to add a static:</p>
-<ul>
-<li>Add a function property to <code>schema.statics</code></li>
-<li>Call the <a href="/docs/api.html#schema_Schema-static"><code>Schema#static()</code> function</a></li>
-</ul>
-<pre><code class="language-javascript">  <span class="hljs-comment">// Assign a function to the "statics" object of our animalSchema</span>
-  animalSchema.statics.findByName = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">name</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.find({ name: <span class="hljs-keyword">new</span> <span class="hljs-built_in">RegExp</span>(name, <span class="hljs-string">'i'</span>) });
-  };
-  <span class="hljs-comment">// Or, equivalently, you can call `animalSchema.static()`.</span>
-  animalSchema.static(<span class="hljs-string">'findByBreed'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">breed</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.find({ breed });
-  });
-
-  <span class="hljs-keyword">const</span> Animal = mongoose.model(<span class="hljs-string">'Animal'</span>, animalSchema);
-  <span class="hljs-keyword">let</span> animals = <span class="hljs-keyword">await</span> Animal.findByName(<span class="hljs-string">'fido'</span>);
-  animls = animals.concat(<span class="hljs-keyword">await</span> Animal.findByBreed(<span class="hljs-string">'Poodle'</span>));</code></pre>
-<p>Do <strong>not</strong> declare statics using ES6 arrow functions (<code>=&gt;</code>). Arrow functions <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this">explicitly prevent binding <code>this</code></a>, so the above examples will not work because of the value of <code>this</code>.</p>
-<h3 id="query-helpers"><a href="#query-helpers">Query Helpers</a></h3>
-
-<p>You can also add query helper functions, which are like instance methods
-but for mongoose queries. Query helper methods let you extend mongoose&#39;s
-<a href="./queries.html">chainable query builder API</a>.</p>
-<pre><code class="language-javascript">  animalSchema.query.byName = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">name</span>) </span>{
-    <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.where({ name: <span class="hljs-keyword">new</span> <span class="hljs-built_in">RegExp</span>(name, <span class="hljs-string">'i'</span>) });
-  };
-
-  <span class="hljs-keyword">var</span> Animal = mongoose.model(<span class="hljs-string">'Animal'</span>, animalSchema);
-
-  Animal.find().byName(<span class="hljs-string">'fido'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, animals</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(animals);
-  });
-
-  Animal.findOne().byName(<span class="hljs-string">'fido'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, animal</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(animal);
-  });</code></pre>
-<h3 id="indexes"><a href="#indexes">Indexes</a></h3>
-
-<p>MongoDB supports <a href="http://docs.mongodb.org/manual/indexes/">secondary indexes</a>.
-With mongoose, we define these indexes within our <code>Schema</code> <a href="./api.html#schematype_SchemaType-index">at</a> <a href="./api.html#schematype_SchemaType-unique">the</a> <a href="./api.html#schematype_SchemaType-sparse">path</a> <a href="./api.html#schema_date_SchemaDate-expires">level</a> or the <code>schema</code> level.
-Defining indexes at the schema level is necessary when creating
-<a href="https://docs.mongodb.com/manual/core/index-compound/">compound indexes</a>.</p>
-<pre><code class="language-javascript">  <span class="hljs-keyword">var</span> animalSchema = <span class="hljs-keyword">new</span> Schema({
-    name: <span class="hljs-built_in">String</span>,
-    type: <span class="hljs-built_in">String</span>,
-    tags: { type: [<span class="hljs-built_in">String</span>], index: <span class="hljs-literal">true</span> } <span class="hljs-comment">// field level</span>
-  });
-
-  animalSchema.index({ name: <span class="hljs-number">1</span>, type: <span class="hljs-number">-1</span> }); <span class="hljs-comment">// schema level</span></code></pre>
-<p>When your application starts up, Mongoose automatically calls <a href="https://docs.mongodb.com/manual/reference/method/db.collection.createIndex/#db.collection.createIndex"><code>createIndex</code></a> for each defined index in your schema.
-Mongoose will call <code>createIndex</code> for each index sequentially, and emit an &#39;index&#39; event on the model when all the <code>createIndex</code> calls succeeded or when there was an error.
-While nice for development, it is recommended this behavior be disabled in production since index creation can cause a <a href="http://docs.mongodb.org/manual/core/indexes/#index-creation-operations">significant performance impact</a>. Disable the behavior by setting the <code>autoIndex</code> option of your schema to <code>false</code>, or globally on the connection by setting the option <code>autoIndex</code> to <code>false</code>.</p>
-<pre><code class="language-javascript">  mongoose.connect(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>, { autoIndex: <span class="hljs-literal">false</span> });
-  <span class="hljs-comment">// or</span>
-  mongoose.createConnection(<span class="hljs-string">'mongodb://user:pass@localhost:port/database'</span>, { autoIndex: <span class="hljs-literal">false</span> });
-  <span class="hljs-comment">// or</span>
-  animalSchema.set(<span class="hljs-string">'autoIndex'</span>, <span class="hljs-literal">false</span>);
-  <span class="hljs-comment">// or</span>
-  <span class="hljs-keyword">new</span> Schema({..}, { autoIndex: <span class="hljs-literal">false</span> });</code></pre>
-<p>Mongoose will emit an <code>index</code> event on the model when indexes are done
-building or an error occurred.</p>
-<pre><code class="language-javascript">  <span class="hljs-comment">// Will cause an error because mongodb has an _id index by default that</span>
-  <span class="hljs-comment">// is not sparse</span>
-  animalSchema.index({ _id: <span class="hljs-number">1</span> }, { sparse: <span class="hljs-literal">true</span> });
-  <span class="hljs-keyword">var</span> Animal = mongoose.model(<span class="hljs-string">'Animal'</span>, animalSchema);
-
-  Animal.on(<span class="hljs-string">'index'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-    <span class="hljs-comment">// "_id index cannot be sparse"</span>
-    <span class="hljs-built_in">console</span>.log(error.message);
-  });</code></pre>
-<p>See also the <a href="./api.html#model_Model.ensureIndexes">Model#ensureIndexes</a> method.</p>
-<h3 id="virtuals"><a href="#virtuals">Virtuals</a></h3>
-
-<p><a href="./api.html#schema_Schema-virtual">Virtuals</a> are document properties that
-you can get and set but that do not get persisted to MongoDB. The getters
-are useful for formatting or combining fields, while setters are useful for
-de-composing a single value into multiple values for storage.</p>
-<pre><code class="language-javascript">  <span class="hljs-comment">// define a schema</span>
-  <span class="hljs-keyword">var</span> personSchema = <span class="hljs-keyword">new</span> Schema({
-    name: {
-      first: <span class="hljs-built_in">String</span>,
-      last: <span class="hljs-built_in">String</span>
-    }
-  });
-
-  <span class="hljs-comment">// compile our model</span>
-  <span class="hljs-keyword">var</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, personSchema);
-
-  <span class="hljs-comment">// create a document</span>
-  <span class="hljs-keyword">var</span> axl = <span class="hljs-keyword">new</span> Person({
-    name: { first: <span class="hljs-string">'Axl'</span>, last: <span class="hljs-string">'Rose'</span> }
-  });</code></pre>
-<p>Suppose you want to print out the person&#39;s full name. You could do it yourself:</p>
-<pre><code class="language-javascript"><span class="hljs-built_in">console</span>.log(axl.name.first + <span class="hljs-string">' '</span> + axl.name.last); <span class="hljs-comment">// Axl Rose</span></code></pre>
-<p>But concatenating the first and last name every time can get cumbersome.
-And what if you want to do some extra processing on the name, like
-<a href="https://www.npmjs.com/package/diacritics">removing diacritics</a>? A
-<a href="./api.html#virtualtype_VirtualType-get">virtual property getter</a> lets you
-define a <code>fullName</code> property that won&#39;t get persisted to MongoDB.</p>
-<pre><code class="language-javascript">personSchema.virtual(<span class="hljs-string">'fullName'</span>).get(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.name.first + <span class="hljs-string">' '</span> + <span class="hljs-keyword">this</span>.name.last;
-});</code></pre>
-<p>Now, mongoose will call your getter function every time you access the
-<code>fullName</code> property:</p>
-<pre><code class="language-javascript"><span class="hljs-built_in">console</span>.log(axl.fullName); <span class="hljs-comment">// Axl Rose</span></code></pre>
-<p>If you use <code>toJSON()</code> or <code>toObject()</code> mongoose will <em>not</em> include virtuals
-by default. This includes the output of calling <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify"><code>JSON.stringify()</code></a>
-on a Mongoose document, because <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#Description"><code>JSON.stringify()</code> calls <code>toJSON()</code></a>.
-Pass <code>{ virtuals: true }</code> to either
-<a href="./api.html#document_Document-toObject"><code>toObject()</code></a> or <a href="./api.html#document_Document-toJSON"><code>toJSON()</code></a>.</p>
-<p>You can also add a custom setter to your virtual that will let you set both
-first name and last name via the <code>fullName</code> virtual.</p>
-<pre><code class="language-javascript">personSchema.virtual(<span class="hljs-string">'fullName'</span>).
-  get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.name.first + <span class="hljs-string">' '</span> + <span class="hljs-keyword">this</span>.name.last; }).
-  set(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-    <span class="hljs-keyword">this</span>.name.first = v.substr(<span class="hljs-number">0</span>, v.indexOf(<span class="hljs-string">' '</span>));
-    <span class="hljs-keyword">this</span>.name.last = v.substr(v.indexOf(<span class="hljs-string">' '</span>) + <span class="hljs-number">1</span>);
-  });
-
-axl.fullName = <span class="hljs-string">'William Rose'</span>; <span class="hljs-comment">// Now `axl.name.first` is "William"</span></code></pre>
-<p>Virtual property setters are applied before other validation. So the example
-above would still work even if the <code>first</code> and <code>last</code> name fields were
-required.</p>
-<p>Only non-virtual properties work as part of queries and for field selection.
-Since virtuals are not stored in MongoDB, you can&#39;t query with them.</p>
-<h5 id="aliases"><a href="#aliases">Aliases</a></h5>
-
-<p>Aliases are a particular type of virtual where the getter and setter
-seamlessly get and set another property. This is handy for saving network
-bandwidth, so you can convert a short property name stored in the database
-into a longer name for code readability.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> personSchema = <span class="hljs-keyword">new</span> Schema({
-  n: {
-    type: <span class="hljs-built_in">String</span>,
-    <span class="hljs-comment">// Now accessing `name` will get you the value of `n`, and setting `n` will set the value of `name`</span>
-    alias: <span class="hljs-string">'name'</span>
-  }
-});
-
-<span class="hljs-comment">// Setting `name` will propagate to `n`</span>
-<span class="hljs-keyword">var</span> person = <span class="hljs-keyword">new</span> Person({ name: <span class="hljs-string">'Val'</span> });
-<span class="hljs-built_in">console</span>.log(person); <span class="hljs-comment">// { n: 'Val' }</span>
-<span class="hljs-built_in">console</span>.log(person.toObject({ virtuals: <span class="hljs-literal">true</span> })); <span class="hljs-comment">// { n: 'Val', name: 'Val' }</span>
-<span class="hljs-built_in">console</span>.log(person.name); <span class="hljs-comment">// "Val"</span>
-
-person.name = <span class="hljs-string">'Not Val'</span>;
-<span class="hljs-built_in">console</span>.log(person); <span class="hljs-comment">// { n: 'Not Val' }</span></code></pre>
-<p>You can also declare aliases on nested paths. It is easier to use nested
-schemas and <a href="/docs/subdocs.html">subdocuments</a>, but you can also declare
-nested path aliases inline as long as you use the full nested path
-<code>nested.myProp</code> as the alias.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> childSchema = <span class="hljs-keyword">new</span> Schema({
-  n: {
-    type: <span class="hljs-built_in">String</span>,
-    alias: <span class="hljs-string">'name'</span>
-  }
-}, { _id: <span class="hljs-literal">false</span> });
-
-<span class="hljs-keyword">const</span> parentSchema = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// If in a child schema, alias doesn't need to include the full nested path</span>
-  c: childSchema,
-  name: {
-    f: {
-      type: <span class="hljs-built_in">String</span>,
-      <span class="hljs-comment">// Alias needs to include the full nested path if declared inline</span>
-      alias: <span class="hljs-string">'name.first'</span>
-    }
-  }
-});</code></pre>
-<h3 id="options"><a href="#options">Options</a></h3>
-
-<p>Schemas have a few configurable options which can be passed to the
-constructor or <code>set</code> directly:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Schema({..}, options);
-
-<span class="hljs-comment">// or</span>
-
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..});
-schema.set(option, value);</code></pre>
-<p>Valid options:</p>
-<ul>
-<li><a href="#autoIndex">autoIndex</a></li>
-<li><a href="#autoCreate">autoCreate</a></li>
-<li><a href="#bufferCommands">bufferCommands</a></li>
-<li><a href="#capped">capped</a></li>
-<li><a href="#collection">collection</a></li>
-<li><a href="#id">id</a></li>
-<li><a href="#_id">_id</a></li>
-<li><a href="#minimize">minimize</a></li>
-<li><a href="#read">read</a></li>
-<li><a href="#writeConcern">writeConcern</a></li>
-<li><a href="#shardKey">shardKey</a></li>
-<li><a href="#strict">strict</a></li>
-<li><a href="#strictQuery">strictQuery</a></li>
-<li><a href="#toJSON">toJSON</a></li>
-<li><a href="#toObject">toObject</a></li>
-<li><a href="#typeKey">typeKey</a></li>
-<li><a href="#useNestedStrict">useNestedStrict</a></li>
-<li><a href="#validateBeforeSave">validateBeforeSave</a></li>
-<li><a href="#versionKey">versionKey</a></li>
-<li><a href="#collation">collation</a></li>
-<li><a href="#selectPopulatedPaths">selectPopulatedPaths</a></li>
-<li><a href="#skipVersioning">skipVersioning</a></li>
-<li><a href="#timestamps">timestamps</a></li>
-<li><a href="#storeSubdocValidationError">storeSubdocValidationError</a></li>
-</ul>
-<h3 id="autoIndex"><a href="#autoIndex">option: autoIndex</a></h3>
-
-<p>By default, Mongoose&#39;s <a href="/docs/api.html#model_Model.init"><code>init()</code> function</a>
-creates all the indexes defined in your model&#39;s schema by calling
-<a href="/docs/api.html#model_Model.createIndexes"><code>Model.createIndexes()</code></a>
-after you successfully connect to MongoDB. Creating indexes automatically is
-great for development and test environments. But index builds can also create
-significant load on your production database. If you want to manage indexes
-carefully in production, you can set <code>autoIndex</code> to false.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { autoIndex: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">const</span> Clock = mongoose.model(<span class="hljs-string">'Clock'</span>, schema);
-Clock.ensureIndexes(callback);</code></pre>
-<p>The <code>autoIndex</code> option is set to <code>true</code> by default. You can change this
-default by setting <code>mongoose.use(&#39;autoIndex&#39;, false);</code></p>
-<h3 id="autoCreate"><a href="#autoCreate">option: autoCreate</a></h3>
-
-<p>Before Mongoose builds indexes, it calls <code>Model.createCollection()</code>
-to create the underlying collection in MongoDB if <code>autoCreate</code> is set to true.
-Calling <code>createCollection()</code>
-sets the <a href="https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations">collection&#39;s default collation</a>
-based on the <a href="#collation">collation option</a> and establishes the collection as
-a capped collection if you set the <a href="#capped"><code>capped</code> schema option</a>. Like
-<code>autoIndex</code>, setting <code>autoCreate</code> to true is helpful for development and
-test environments.</p>
-<p>Unfortunately, <code>createCollection()</code> cannot change an existing collection.
-For example, if you add <code>capped: 1024</code> to your schema and the existing
-collection is not capped, <code>createCollection()</code> will throw an error.
-Generally, <code>autoCreate</code> should be <code>false</code> for production environments.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { autoCreate: <span class="hljs-literal">true</span>, capped: <span class="hljs-number">1024</span> });
-<span class="hljs-keyword">const</span> Clock = mongoose.model(<span class="hljs-string">'Clock'</span>, schema);
-<span class="hljs-comment">// Mongoose will create the capped collection for you.</span></code></pre>
-<p>Unlike <code>autoIndex</code>, <code>autoCreate</code> is <code>false</code> by default. You can change this
-default by setting <code>mongoose.use(&#39;autoCreate&#39;, true);</code></p>
-<h3 id="bufferCommands"><a href="#bufferCommands">option: bufferCommands</a></h3>
-
-<p>By default, mongoose buffers commands when the connection goes down until
-the driver manages to reconnect. To disable buffering, set <code>bufferCommands</code>
-to false.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { bufferCommands: <span class="hljs-literal">false</span> });</code></pre>
-<p>The schema <code>bufferCommands</code> option overrides the global <code>bufferCommands</code> option.</p>
-<pre><code class="language-javascript">mongoose.set(<span class="hljs-string">'bufferCommands'</span>, <span class="hljs-literal">true</span>);
-<span class="hljs-comment">// Schema option below overrides the above, if the schema option is set.</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { bufferCommands: <span class="hljs-literal">false</span> });</code></pre>
-<h3 id="capped"><a href="#capped">option: capped</a></h3>
-
-<p>Mongoose supports MongoDBs <a href="http://www.mongodb.org/display/DOCS/Capped+Collections">capped</a>
-collections. To specify the underlying MongoDB collection be <code>capped</code>, set
-the <code>capped</code> option to the maximum size of the collection in
-<a href="http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-size.">bytes</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Schema({..}, { capped: <span class="hljs-number">1024</span> });</code></pre>
-<p>The <code>capped</code> option may also be set to an object if you want to pass
-additional options like <a href="http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-max">max</a>
-or <a href="http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-autoIndexId">autoIndexId</a>.
-In this case you must explicitly pass the <code>size</code> option, which is required.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Schema({..}, { capped: { size: <span class="hljs-number">1024</span>, max: <span class="hljs-number">1000</span>, autoIndexId: <span class="hljs-literal">true</span> } });</code></pre>
-<h3 id="collection"><a href="#collection">option: collection</a></h3>
-
-<p>Mongoose by default produces a collection name by passing the model name to
-the <a href="./api.html#utils_exports.toCollectionName">utils.toCollectionName</a> method.
-This method pluralizes the name. Set this option if you need a different name
-for your collection.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> dataSchema = <span class="hljs-keyword">new</span> Schema({..}, { collection: <span class="hljs-string">'data'</span> });</code></pre>
-<h3 id="id"><a href="#id">option: id</a></h3>
-
-<p>Mongoose assigns each of your schemas an <code>id</code> virtual getter by default
-which returns the documents <code>_id</code> field cast to a string, or in the case of
-ObjectIds, its hexString. If you don&#39;t want an <code>id</code> getter added to your
-schema, you may disable it passing this option at schema construction time.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// default behavior</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">var</span> Page = mongoose.model(<span class="hljs-string">'Page'</span>, schema);
-<span class="hljs-keyword">var</span> p = <span class="hljs-keyword">new</span> Page({ name: <span class="hljs-string">'mongodb.org'</span> });
-<span class="hljs-built_in">console</span>.log(p.id); <span class="hljs-comment">// '50341373e894ad16347efe01'</span>
-
-<span class="hljs-comment">// disabled id</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { id: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">var</span> Page = mongoose.model(<span class="hljs-string">'Page'</span>, schema);
-<span class="hljs-keyword">var</span> p = <span class="hljs-keyword">new</span> Page({ name: <span class="hljs-string">'mongodb.org'</span> });
-<span class="hljs-built_in">console</span>.log(p.id); <span class="hljs-comment">// undefined</span></code></pre>
-<h3 id="_id"><a href="#_id">option: _id</a></h3>
-
-<p>Mongoose assigns each of your schemas an <code>_id</code> field by default if one
-is not passed into the <a href="/docs/api.html#schema-js">Schema</a> constructor.
-The type assigned is an <a href="/docs/api.html#schema_Schema.Types">ObjectId</a>
-to coincide with MongoDB&#39;s default behavior. If you don&#39;t want an <code>_id</code>
-added to your schema at all, you may disable it using this option.</p>
-<p>You can <strong>only</strong> use this option on subdocuments. Mongoose can&#39;t
-save a document without knowing its id, so you will get an error if
-you try to save a document without an <code>_id</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// default behavior</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">var</span> Page = mongoose.model(<span class="hljs-string">'Page'</span>, schema);
-<span class="hljs-keyword">var</span> p = <span class="hljs-keyword">new</span> Page({ name: <span class="hljs-string">'mongodb.org'</span> });
-<span class="hljs-built_in">console</span>.log(p); <span class="hljs-comment">// { _id: '50341373e894ad16347efe01', name: 'mongodb.org' }</span>
-
-<span class="hljs-comment">// disabled _id</span>
-<span class="hljs-keyword">var</span> childSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { _id: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> Schema({ children: [childSchema] });
-
-<span class="hljs-keyword">var</span> Model = mongoose.model(<span class="hljs-string">'Model'</span>, parentSchema);
-
-Model.create({ children: [{ name: <span class="hljs-string">'Luke'</span> }] }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc</span>) </span>{
-  <span class="hljs-comment">// doc.children[0]._id will be undefined</span>
-});</code></pre>
-<h3 id="minimize"><a href="#minimize">option: minimize</a></h3>
-
-<p>Mongoose will, by default, &quot;minimize&quot; schemas by removing empty objects.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, inventory: {} });
-<span class="hljs-keyword">const</span> Character = mongoose.model(<span class="hljs-string">'Character'</span>, schema);
-
-<span class="hljs-comment">// will store `inventory` field if it is not empty</span>
-<span class="hljs-keyword">const</span> frodo = <span class="hljs-keyword">new</span> Character({ name: <span class="hljs-string">'Frodo'</span>, inventory: { ringOfPower: <span class="hljs-number">1</span> }});
-<span class="hljs-keyword">await</span> frodo.save();
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Character.findOne({ name: <span class="hljs-string">'Frodo'</span> }).lean();
-doc.inventory; <span class="hljs-comment">// { ringOfPower: 1 }</span>
-
-<span class="hljs-comment">// will not store `inventory` field if it is empty</span>
-<span class="hljs-keyword">const</span> sam = <span class="hljs-keyword">new</span> Character({ name: <span class="hljs-string">'Sam'</span>, inventory: {}});
-<span class="hljs-keyword">await</span> sam.save();
-doc = <span class="hljs-keyword">await</span> Character.findOne({ name: <span class="hljs-string">'Sam'</span> }).lean();
-doc.inventory; <span class="hljs-comment">// undefined</span></code></pre>
-<p>This behavior can be overridden by setting <code>minimize</code> option to <code>false</code>. It
-will then store empty objects.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span>, inventory: {} }, { minimize: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">const</span> Character = mongoose.model(<span class="hljs-string">'Character'</span>, schema);
-
-<span class="hljs-comment">// will store `inventory` if empty</span>
-<span class="hljs-keyword">const</span> sam = <span class="hljs-keyword">new</span> Character({ name: <span class="hljs-string">'Sam'</span>, inventory: {} });
-<span class="hljs-keyword">await</span> sam.save();
-doc = <span class="hljs-keyword">await</span> Character.findOne({ name: <span class="hljs-string">'Sam'</span> }).lean();
-doc.inventory; <span class="hljs-comment">// {}</span></code></pre>
-<p>To check whether an object is empty, you can use the <code>$isEmpty()</code> helper:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> sam = <span class="hljs-keyword">new</span> Character({ name: <span class="hljs-string">'Sam'</span>, inventory: {} });
-sam.$isEmpty(<span class="hljs-string">'inventory'</span>); <span class="hljs-comment">// true</span>
-
-sam.inventory.barrowBlade = <span class="hljs-number">1</span>;
-sam.$isEmpty(<span class="hljs-string">'inventory'</span>); <span class="hljs-comment">// false</span></code></pre>
-<h3 id="read"><a href="#read">option: read</a></h3>
-
-<p>Allows setting <a href="/docs/api.html#query_Query-read">query#read</a> options at the
-schema level, providing us a way to apply default
-<a href="http://docs.mongodb.org/manual/applications/replication/#replica-set-read-preference">ReadPreferences</a>
-to all queries derived from a model.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { read: <span class="hljs-string">'primary'</span> });            <span class="hljs-comment">// also aliased as 'p'</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { read: <span class="hljs-string">'primaryPreferred'</span> });   <span class="hljs-comment">// aliased as 'pp'</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { read: <span class="hljs-string">'secondary'</span> });          <span class="hljs-comment">// aliased as 's'</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { read: <span class="hljs-string">'secondaryPreferred'</span> }); <span class="hljs-comment">// aliased as 'sp'</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { read: <span class="hljs-string">'nearest'</span> });            <span class="hljs-comment">// aliased as 'n'</span></code></pre>
-<p>The alias of each pref is also permitted so instead of having to type out
-&#39;secondaryPreferred&#39; and getting the spelling wrong, we can simply pass &#39;sp&#39;.</p>
-<p>The read option also allows us to specify <em>tag sets</em>. These tell the
-<a href="https://github.com/mongodb/node-mongodb-native/">driver</a> from which members
-of the replica-set it should attempt to read. Read more about tag sets
-<a href="http://docs.mongodb.org/manual/applications/replication/#tag-sets">here</a> and
-<a href="http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences">here</a>.</p>
-<p><em>NOTE: you may also specify the driver read pref <a href="http://mongodb.github.com/node-mongodb-native/api-generated/replset.html?highlight=strategy">strategy</a>
-option when connecting:</em></p>
-<pre><code class="language-javascript"><span class="hljs-comment">// pings the replset members periodically to track network latency</span>
-<span class="hljs-keyword">var</span> options = { replset: { strategy: <span class="hljs-string">'ping'</span> }};
-mongoose.connect(uri, options);
-
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({..}, { read: [<span class="hljs-string">'nearest'</span>, { disk: <span class="hljs-string">'ssd'</span> }] });
-mongoose.model(<span class="hljs-string">'JellyBean'</span>, schema);</code></pre>
-<h3 id="writeConcern"><a href="#writeConcern">option: writeConcern</a></h3>
-
-<p>Allows setting <a href="https://docs.mongodb.com/manual/reference/write-concern/">write concern</a>
-at the schema level.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, {
-  writeConcern: {
-    w: <span class="hljs-string">'majority'</span>,
-    j: <span class="hljs-literal">true</span>,
-    wtimeout: <span class="hljs-number">1000</span>
-  }
-});</code></pre>
-<h3 id="shardKey"><a href="#shardKey">option: shardKey</a></h3>
-
-<p>The <code>shardKey</code> option is used when we have a <a href="http://www.mongodb.org/display/DOCS/Sharding+Introduction">sharded MongoDB architecture</a>.
-Each sharded collection is given a shard key which must be present in all
-insert/update operations. We just need to set this schema option to the same
-shard key and we’ll be all set.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Schema({ .. }, { shardKey: { tag: <span class="hljs-number">1</span>, name: <span class="hljs-number">1</span> }})</code></pre>
-<p><em>Note that Mongoose does not send the <code>shardcollection</code> command for you. You
-must configure your shards yourself.</em></p>
-<h3 id="strict">option: strict</h3>
-
-<p>The strict option, (enabled by default), ensures that values passed to our
-model constructor that were not specified in our schema do not get saved to
-the db.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> thingSchema = <span class="hljs-keyword">new</span> Schema({..})
-<span class="hljs-keyword">var</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, thingSchema);
-<span class="hljs-keyword">var</span> thing = <span class="hljs-keyword">new</span> Thing({ iAmNotInTheSchema: <span class="hljs-literal">true</span> });
-thing.save(); <span class="hljs-comment">// iAmNotInTheSchema is not saved to the db</span>
-
-<span class="hljs-comment">// set to false..</span>
-<span class="hljs-keyword">var</span> thingSchema = <span class="hljs-keyword">new</span> Schema({..}, { strict: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">var</span> thing = <span class="hljs-keyword">new</span> Thing({ iAmNotInTheSchema: <span class="hljs-literal">true</span> });
-thing.save(); <span class="hljs-comment">// iAmNotInTheSchema is now saved to the db!!</span></code></pre>
-<p>This also affects the use of <code>doc.set()</code> to set a property value.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> thingSchema = <span class="hljs-keyword">new</span> Schema({..})
-<span class="hljs-keyword">var</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, thingSchema);
-<span class="hljs-keyword">var</span> thing = <span class="hljs-keyword">new</span> Thing;
-thing.set(<span class="hljs-string">'iAmNotInTheSchema'</span>, <span class="hljs-literal">true</span>);
-thing.save(); <span class="hljs-comment">// iAmNotInTheSchema is not saved to the db</span></code></pre>
-<p>This value can be overridden at the model instance level by passing a second
-boolean argument:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>);
-<span class="hljs-keyword">var</span> thing = <span class="hljs-keyword">new</span> Thing(doc, <span class="hljs-literal">true</span>);  <span class="hljs-comment">// enables strict mode</span>
-<span class="hljs-keyword">var</span> thing = <span class="hljs-keyword">new</span> Thing(doc, <span class="hljs-literal">false</span>); <span class="hljs-comment">// disables strict mode</span></code></pre>
-<p>The <code>strict</code> option may also be set to <code>&quot;throw&quot;</code> which will cause errors
-to be produced instead of dropping the bad data.</p>
-<p><em>NOTE: Any key/val set on the instance that does not exist in your schema is always ignored, regardless of schema option.</em></p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> thingSchema = <span class="hljs-keyword">new</span> Schema({..})
-<span class="hljs-keyword">var</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, thingSchema);
-<span class="hljs-keyword">var</span> thing = <span class="hljs-keyword">new</span> Thing;
-thing.iAmNotInTheSchema = <span class="hljs-literal">true</span>;
-thing.save(); <span class="hljs-comment">// iAmNotInTheSchema is never saved to the db</span></code></pre>
-<h3 id="strictQuery">option: strictQuery</h3>
-
-<p>For backwards compatibility, the <code>strict</code> option does <strong>not</strong> apply to
-the <code>filter</code> parameter for queries.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> mySchema = <span class="hljs-keyword">new</span> Schema({ field: <span class="hljs-built_in">Number</span> }, { strict: <span class="hljs-literal">true</span> });
-<span class="hljs-keyword">const</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, mySchema);
-
-<span class="hljs-comment">// Mongoose will **not** filter out `notInSchema: 1`, despite `strict: true`</span>
-MyModel.find({ notInSchema: <span class="hljs-number">1</span> });</code></pre>
-<p>The <code>strict</code> option does apply to updates.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Mongoose will strip out `notInSchema` from the update if `strict` is</span>
-<span class="hljs-comment">// not `false`</span>
-MyModel.updateMany({}, { $set: { notInSchema: <span class="hljs-number">1</span> } });</code></pre>
-<p>Mongoose has a separate <code>strictQuery</code> option to toggle strict mode for
-the <code>filter</code> parameter to queries.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> mySchema = <span class="hljs-keyword">new</span> Schema({ field: <span class="hljs-built_in">Number</span> }, {
-  strict: <span class="hljs-literal">true</span>,
-  strictQuery: <span class="hljs-literal">true</span> <span class="hljs-comment">// Turn on strict mode for query filters</span>
-});
-<span class="hljs-keyword">const</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, mySchema);
-
-<span class="hljs-comment">// Mongoose will strip out `notInSchema: 1` because `strictQuery` is `true`</span>
-MyModel.find({ notInSchema: <span class="hljs-number">1</span> });</code></pre>
-<h3 id="toJSON"><a href="#toJSON">option: toJSON</a></h3>
-
-<p>Exactly the same as the <a href="#toObject">toObject</a> option but only applies when
-the documents <code>toJSON</code> method is called.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>).get(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">v</span>) </span>{
-  <span class="hljs-keyword">return</span> v + <span class="hljs-string">' is my name'</span>;
-});
-schema.set(<span class="hljs-string">'toJSON'</span>, { getters: <span class="hljs-literal">true</span>, virtuals: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">var</span> M = mongoose.model(<span class="hljs-string">'Person'</span>, schema);
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M({ name: <span class="hljs-string">'Max Headroom'</span> });
-<span class="hljs-built_in">console</span>.log(m.toObject()); <span class="hljs-comment">// { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom' }</span>
-<span class="hljs-built_in">console</span>.log(m.toJSON()); <span class="hljs-comment">// { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }</span>
-<span class="hljs-comment">// since we know toJSON is called whenever a js object is stringified:</span>
-<span class="hljs-built_in">console</span>.log(<span class="hljs-built_in">JSON</span>.stringify(m)); <span class="hljs-comment">// { "_id": "504e0cd7dd992d9be2f20b6f", "name": "Max Headroom is my name" }</span></code></pre>
-<p>To see all available <code>toJSON/toObject</code> options, read <a href="/docs/api.html#document_Document-toObject">this</a>.</p>
-<h3 id="toObject"><a href="#toObject">option: toObject</a></h3>
-
-<p>Documents have a <a href="/docs/api.html#document_Document-toObject">toObject</a> method
-which converts the mongoose document into a plain javascript object. This
-method accepts a few options. Instead of applying these options on a
-per-document basis we may declare the options here and have it applied to
-all of this schemas documents by default.</p>
-<p>To have all virtuals show up in your <code>console.log</code> output, set the
-<code>toObject</code> option to <code>{ getters: true }</code>:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>).get(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">v</span>) </span>{
-  <span class="hljs-keyword">return</span> v + <span class="hljs-string">' is my name'</span>;
-});
-schema.set(<span class="hljs-string">'toObject'</span>, { getters: <span class="hljs-literal">true</span> });
-<span class="hljs-keyword">var</span> M = mongoose.model(<span class="hljs-string">'Person'</span>, schema);
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M({ name: <span class="hljs-string">'Max Headroom'</span> });
-<span class="hljs-built_in">console</span>.log(m); <span class="hljs-comment">// { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }</span></code></pre>
-<p>To see all available <code>toObject</code> options, read <a href="/docs/api.html#document_Document-toObject">this</a>.</p>
-<h3 id="typeKey"><a href="#typeKey">option: typeKey</a></h3>
-
-<p>By default, if you have an object with key &#39;type&#39; in your schema, mongoose
-will interpret it as a type declaration.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Mongoose interprets this as 'loc is a String'</span>
-<span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ loc: { type: <span class="hljs-built_in">String</span>, coordinates: [<span class="hljs-built_in">Number</span>] } });</code></pre>
-<p>However, for applications like <a href="http://docs.mongodb.org/manual/reference/geojson/">geoJSON</a>,
-the &#39;type&#39; property is important. If you want to control which key mongoose
-uses to find type declarations, set the &#39;typeKey&#39; schema option.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// Mongoose interpets this as 'loc is an object with 2 keys, type and coordinates'</span>
-  loc: { type: <span class="hljs-built_in">String</span>, coordinates: [<span class="hljs-built_in">Number</span>] },
-  <span class="hljs-comment">// Mongoose interprets this as 'name is a String'</span>
-  name: { $type: <span class="hljs-built_in">String</span> }
-}, { typeKey: <span class="hljs-string">'$type'</span> }); <span class="hljs-comment">// A '$type' key means this object is a type declaration</span></code></pre>
-<h3 id="validateBeforeSave"><a href="#validateBeforeSave">option: validateBeforeSave</a></h3>
-
-<p>By default, documents are automatically validated before they are saved to
-the database. This is to prevent saving an invalid document. If you want to
-handle validation manually, and be able to save objects which don&#39;t pass
-validation, you can set <code>validateBeforeSave</code> to false.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.set(<span class="hljs-string">'validateBeforeSave'</span>, <span class="hljs-literal">false</span>);
-schema.path(<span class="hljs-string">'name'</span>).validate(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">value</span>) </span>{
-    <span class="hljs-keyword">return</span> v != <span class="hljs-literal">null</span>;
-});
-<span class="hljs-keyword">var</span> M = mongoose.model(<span class="hljs-string">'Person'</span>, schema);
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> M({ name: <span class="hljs-literal">null</span> });
-m.validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-    <span class="hljs-built_in">console</span>.log(err); <span class="hljs-comment">// Will tell you that null is not allowed.</span>
-});
-m.save(); <span class="hljs-comment">// Succeeds despite being invalid</span></code></pre>
-<h3 id="versionKey"><a href="#versionKey">option: versionKey</a></h3>
-
-<p>The <code>versionKey</code> is a property set on each document when first created by
-Mongoose. This keys value contains the internal
-<a href="http://aaronheckmann.tumblr.com/post/48943525537/mongoose-v3-part-1-versioning">revision</a>
-of the document. The <code>versionKey</code> option is a string that represents the
-path to use for versioning. The default is <code>__v</code>. If this conflicts with
-your application you can configure as such:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-string">'string'</span> });
-<span class="hljs-keyword">const</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, schema);
-<span class="hljs-keyword">const</span> thing = <span class="hljs-keyword">new</span> Thing({ name: <span class="hljs-string">'mongoose v3'</span> });
-<span class="hljs-keyword">await</span> thing.save(); <span class="hljs-comment">// { __v: 0, name: 'mongoose v3' }</span>
-
-<span class="hljs-comment">// customized versionKey</span>
-<span class="hljs-keyword">new</span> Schema({..}, { versionKey: <span class="hljs-string">'_somethingElse'</span> })
-<span class="hljs-keyword">const</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, schema);
-<span class="hljs-keyword">const</span> thing = <span class="hljs-keyword">new</span> Thing({ name: <span class="hljs-string">'mongoose v3'</span> });
-thing.save(); <span class="hljs-comment">// { _somethingElse: 0, name: 'mongoose v3' }</span></code></pre>
-<p>Note that Mongoose versioning is <strong>not</strong> a full <a href="https://en.wikipedia.org/wiki/Optimistic_concurrency_control">optimistic concurrency</a>
-solution. Use <a href="https://github.com/eoin-obrien/mongoose-update-if-current">mongoose-update-if-current</a>
-for OCC support. Mongoose versioning only operates on arrays:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// 2 copies of the same document</span>
-<span class="hljs-keyword">const</span> doc1 = <span class="hljs-keyword">await</span> Model.findOne({ _id });
-<span class="hljs-keyword">const</span> doc2 = <span class="hljs-keyword">await</span> Model.findOne({ _id });
-
-<span class="hljs-comment">// Delete first 3 comments from `doc1`</span>
-doc1.comments.splice(<span class="hljs-number">0</span>, <span class="hljs-number">3</span>);
-<span class="hljs-keyword">await</span> doc1.save();
-
-<span class="hljs-comment">// The below `save()` will throw a VersionError, because you're trying to</span>
-<span class="hljs-comment">// modify the comment at index 1, and the above `splice()` removed that</span>
-<span class="hljs-comment">// comment.</span>
-doc2.set(<span class="hljs-string">'comments.1.body'</span>, <span class="hljs-string">'new comment'</span>);
-<span class="hljs-keyword">await</span> doc2.save();</code></pre>
-<p>Document versioning can also be disabled by setting the <code>versionKey</code> to
-<code>false</code>.
-<em>DO NOT disable versioning unless you <a href="http://aaronheckmann.tumblr.com/post/48943525537/mongoose-v3-part-1-versioning">know what you are doing</a>.</em></p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Schema({..}, { versionKey: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">const</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, schema);
-<span class="hljs-keyword">const</span> thing = <span class="hljs-keyword">new</span> Thing({ name: <span class="hljs-string">'no versioning please'</span> });
-thing.save(); <span class="hljs-comment">// { name: 'no versioning please' }</span></code></pre>
-<p>Mongoose <em>only</em> updates the version key when you use <a href="/docs/api.html#document_Document-save"><code>save()</code></a>.
-If you use <code>update()</code>, <code>findOneAndUpdate()</code>, etc. Mongoose will <strong>not</strong>
-update the version key. As a workaround, you can use the below middleware.</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'findOneAndUpdate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">const</span> update = <span class="hljs-keyword">this</span>.getUpdate();
-  <span class="hljs-keyword">if</span> (update.__v != <span class="hljs-literal">null</span>) {
-    <span class="hljs-keyword">delete</span> update.__v;
-  }
-  <span class="hljs-keyword">const</span> keys = [<span class="hljs-string">'$set'</span>, <span class="hljs-string">'$setOnInsert'</span>];
-  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">const</span> key <span class="hljs-keyword">of</span> keys) {
-    <span class="hljs-keyword">if</span> (update[key] != <span class="hljs-literal">null</span> &amp;&amp; update[key].__v != <span class="hljs-literal">null</span>) {
-      <span class="hljs-keyword">delete</span> update[key].__v;
-      <span class="hljs-keyword">if</span> (<span class="hljs-built_in">Object</span>.keys(update[key]).length === <span class="hljs-number">0</span>) {
-        <span class="hljs-keyword">delete</span> update[key];
-      }
-    }
-  }
-  update.$inc = update.$inc || {};
-  update.$inc.__v = <span class="hljs-number">1</span>;
-});</code></pre>
-<h3 id="collation"><a href="#collation">option: collation</a></h3>
-
-<p>Sets a default <a href="https://docs.mongodb.com/manual/reference/collation/">collation</a>
-for every query and aggregation. <a href="http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations">Here&#39;s a beginner-friendly overview of collations</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>
-}, { collation: { locale: <span class="hljs-string">'en_US'</span>, strength: <span class="hljs-number">1</span> } });
-
-<span class="hljs-keyword">var</span> MyModel = db.model(<span class="hljs-string">'MyModel'</span>, schema);
-
-MyModel.create([{ name: <span class="hljs-string">'val'</span> }, { name: <span class="hljs-string">'Val'</span> }]).
-  then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-    <span class="hljs-keyword">return</span> MyModel.find({ name: <span class="hljs-string">'val'</span> });
-  }).
-  then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">docs</span>) </span>{
-    <span class="hljs-comment">// `docs` will contain both docs, because `strength: 1` means</span>
-    <span class="hljs-comment">// MongoDB will ignore case when matching.</span>
-  });</code></pre>
-<h3 id="skipVersioning"><a href="#skipVersioning">option: skipVersioning</a></h3>
-
-<p><code>skipVersioning</code> allows excluding paths from versioning (i.e., the internal
-revision will not be incremented even if these paths are updated). DO NOT
-do this unless you know what you&#39;re doing. For subdocuments, include this
-on the parent document using the fully qualified path.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Schema({..}, { skipVersioning: { dontVersionMe: <span class="hljs-literal">true</span> } });
-thing.dontVersionMe.push(<span class="hljs-string">'hey'</span>);
-thing.save(); <span class="hljs-comment">// version is not incremented</span></code></pre>
-<h3 id="timestamps"><a href="#timestamps">option: timestamps</a></h3>
-
-<p>If set <code>timestamps</code>, mongoose assigns <code>createdAt</code> and <code>updatedAt</code> fields to
-your schema, the type assigned is <a href="./api.html#schema-date-js">Date</a>.</p>
-<p>By default, the name of two fields are <code>createdAt</code> and <code>updatedAt</code>, customize
-the field name by setting <code>timestamps.createdAt</code> and <code>timestamps.updatedAt</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> thingSchema = <span class="hljs-keyword">new</span> Schema({..}, { timestamps: { createdAt: <span class="hljs-string">'created_at'</span> } });
-<span class="hljs-keyword">const</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, thingSchema);
-<span class="hljs-keyword">const</span> thing = <span class="hljs-keyword">new</span> Thing();
-<span class="hljs-keyword">await</span> thing.save(); <span class="hljs-comment">// `created_at` &amp; `updatedAt` will be included</span>
-
-<span class="hljs-comment">// With updates, Mongoose will add `updatedAt` to `$set`</span>
-<span class="hljs-keyword">await</span> Thing.updateOne({}, { $set: { name: <span class="hljs-string">'Test'</span> } });
-
-<span class="hljs-comment">// If you set upsert: true, Mongoose will add `created_at` to `$setOnInsert` as well</span>
-<span class="hljs-keyword">await</span> Thing.findOneAndUpdate({}, { $set: { name: <span class="hljs-string">'Test2'</span> } });
-
-<span class="hljs-comment">// Mongoose also adds timestamps to bulkWrite() operations</span>
-<span class="hljs-comment">// See https://mongoosejs.com/docs/api.html#model_Model.bulkWrite</span>
-<span class="hljs-keyword">await</span> Thing.bulkWrite([
-  insertOne: {
-    <span class="hljs-built_in">document</span>: {
-      name: <span class="hljs-string">'Jean-Luc Picard'</span>,
-      ship: <span class="hljs-string">'USS Stargazer'</span>
-      <span class="hljs-comment">// Mongoose will add `created_at` and `updatedAt`</span>
-    }
-  },
-  updateOne: {
-    filter: { name: <span class="hljs-string">'Jean-Luc Picard'</span> },
-    update: {
-      $set: {
-        ship: <span class="hljs-string">'USS Enterprise'</span>
-        <span class="hljs-comment">// Mongoose will add `updatedAt`</span>
-      }
-    }
-  }
-]);</code></pre>
-<h3 id="useNestedStrict"><a href="#useNestedStrict">option: useNestedStrict</a></h3>
-
-<p>Write operations like <code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>,
-and <code>findOneAndUpdate()</code> only check the top-level
-schema&#39;s strict mode setting.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> childSchema = <span class="hljs-keyword">new</span> Schema({}, { strict: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> Schema({ child: childSchema }, { strict: <span class="hljs-string">'throw'</span> });
-<span class="hljs-keyword">var</span> Parent = mongoose.model(<span class="hljs-string">'Parent'</span>, parentSchema);
-Parent.update({}, { <span class="hljs-string">'child.name'</span>: <span class="hljs-string">'Luke Skywalker'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// Error because parentSchema has `strict: throw`, even though</span>
-  <span class="hljs-comment">// `childSchema` has `strict: false`</span>
-});
-
-<span class="hljs-keyword">var</span> update = { <span class="hljs-string">'child.name'</span>: <span class="hljs-string">'Luke Skywalker'</span> };
-<span class="hljs-keyword">var</span> opts = { strict: <span class="hljs-literal">false</span> };
-Parent.update({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// This works because passing `strict: false` to `update()` overwrites</span>
-  <span class="hljs-comment">// the parent schema.</span>
-});</code></pre>
-<p>If you set <code>useNestedStrict</code> to true, mongoose will use the child schema&#39;s
-<code>strict</code> option for casting updates.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> childSchema = <span class="hljs-keyword">new</span> Schema({}, { strict: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> Schema({ child: childSchema },
-  { strict: <span class="hljs-string">'throw'</span>, useNestedStrict: <span class="hljs-literal">true</span> });
-<span class="hljs-keyword">var</span> Parent = mongoose.model(<span class="hljs-string">'Parent'</span>, parentSchema);
-Parent.update({}, { <span class="hljs-string">'child.name'</span>: <span class="hljs-string">'Luke Skywalker'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// Works!</span>
-});</code></pre>
-<h3 id="selectPopulatedPaths">
-  <a href="#selectPopulatedPaths">
-    option: selectPopulatedPaths
-  </a>
-</h3>
-
-<p>By default, Mongoose will automatically <code>select()</code> any populated paths for
-you, unless you explicitly exclude them.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> bookSchema = <span class="hljs-keyword">new</span> Schema({
-  title: <span class="hljs-string">'String'</span>,
-  author: { type: <span class="hljs-string">'ObjectId'</span>, ref: <span class="hljs-string">'Person'</span> }
-});
-<span class="hljs-keyword">const</span> Book = mongoose.model(<span class="hljs-string">'Book'</span>, bookSchema);
-
-<span class="hljs-comment">// By default, Mongoose will add `author` to the below `select()`.</span>
-<span class="hljs-keyword">await</span> Book.find().select(<span class="hljs-string">'title'</span>).populate(<span class="hljs-string">'author'</span>);
-
-<span class="hljs-comment">// In other words, the below query is equivalent to the above</span>
-<span class="hljs-keyword">await</span> Book.find().select(<span class="hljs-string">'title author'</span>).populate(<span class="hljs-string">'author'</span>);</code></pre>
-<p>To opt out of selecting populated fields by default, set <code>selectPopulatedPaths</code>
-to <code>false</code> in your schema.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> bookSchema = <span class="hljs-keyword">new</span> Schema({
-  title: <span class="hljs-string">'String'</span>,
-  author: { type: <span class="hljs-string">'ObjectId'</span>, ref: <span class="hljs-string">'Person'</span> }
-}, { selectPopulatedPaths: <span class="hljs-literal">false</span> });
-<span class="hljs-keyword">const</span> Book = mongoose.model(<span class="hljs-string">'Book'</span>, bookSchema);
-
-<span class="hljs-comment">// Because `selectPopulatedPaths` is false, the below doc will **not**</span>
-<span class="hljs-comment">// contain an `author` property.</span>
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Book.findOne().select(<span class="hljs-string">'title'</span>).populate(<span class="hljs-string">'author'</span>);</code></pre>
-<h3 id="storeSubdocValidationError">
-  <a href="#storeSubdocValidationError">
-    option: storeSubdocValidationError
-  </a>
-</h3>
-
-<p>For legacy reasons, when there is a validation error in subpath of a
-single nested schema, Mongoose will record that there was a validation error
-in the single nested schema path as well. For example:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> childSchema = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> } });
-<span class="hljs-keyword">const</span> parentSchema = <span class="hljs-keyword">new</span> Schema({ child: childSchema });
-
-<span class="hljs-keyword">const</span> Parent = mongoose.model(<span class="hljs-string">'Parent'</span>, parentSchema);
-
-<span class="hljs-comment">// Will contain an error for both 'child.name' _and_ 'child'</span>
-<span class="hljs-keyword">new</span> Parent({ child: {} }).validateSync().errors;</code></pre>
-<p>Set the <code>storeSubdocValidationError</code> to <code>false</code> on the child schema to make
-Mongoose only report the parent error.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> childSchema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> }
-}, { storeSubdocValidationError: <span class="hljs-literal">false</span> }); <span class="hljs-comment">// &lt;-- set on the child schema</span>
-<span class="hljs-keyword">const</span> parentSchema = <span class="hljs-keyword">new</span> Schema({ child: childSchema });
-
-<span class="hljs-keyword">const</span> Parent = mongoose.model(<span class="hljs-string">'Parent'</span>, parentSchema);
-
-<span class="hljs-comment">// Will only contain an error for 'child.name'</span>
-<span class="hljs-keyword">new</span> Parent({ child: {} }).validateSync().errors;</code></pre>
-<h3 id="plugins"><a href="#plugins">Pluggable</a></h3>
-
-<p>Schemas are also <a href="./plugins.html">pluggable</a> which allows us to package up reusable features into
-plugins that can be shared with the community or just between your projects.</p>
-<h3 id="further-reading">Further Reading</h3>
-
-<p>To get the most out of MongoDB, you need to learn the basics of MongoDB schema design.
-SQL schema design (third normal form) was designed to <a href="https://en.wikipedia.org/wiki/Third_normal_form">minimize storage costs</a>,
-whereas MongoDB schema design is about making common queries as fast as possible.
-The <a href="https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-1"><em>6 Rules of Thumb for MongoDB Schema Design</em> blog series</a>
-is an excellent resource for learning the basic rules for making your queries
-fast.</p>
-<p>Users looking to master MongoDB schema design in Node.js should look into
-<a href="http://bit.ly/mongodb-schema-design"><em>The Little MongoDB Schema Design Book</em></a>
-by Christian Kvalheim, the original author of the <a href="http://npmjs.com/package/mongodb">MongoDB Node.js driver</a>.
-This book shows you how to implement performant schemas for a laundry list
-of use cases, including ecommerce, wikis, and appointment bookings.</p>
-<h3 id="next">Next Up</h3>
-
-<p>Now that we&#39;ve covered <code>Schemas</code>, let&#39;s take a look at <a href="/docs/schematypes.html">SchemaTypes</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/guides.html b/docs/guides.html
deleted file mode 100644
index 396952ffdc2..00000000000
--- a/docs/guides.html
+++ /dev/null
@@ -1,101 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Schemas</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="guides">Guides</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Mongoose guides provide detailed tutorials on Mongoose&#39;s core concepts and
-integrating Mongoose with external tools and frameworks.</p>
-<h3 id="mongoose-core-concepts">Mongoose Core Concepts</h3>
-<ul>
-<li><a href="/docs/guide.html">Schemas</a></li>
-<li><a href="/docs/schematypes.html">SchemaTypes</a></li>
-<li><a href="/docs/connections.html">Connections</a></li>
-<li><a href="/docs/models.html">Models</a></li>
-<li><a href="/docs/documents.html">Documents</a></li>
-<li><a href="/docs/subdocs.html">Subdocuments</a></li>
-<li><a href="/docs/queries.html">Queries</a></li>
-<li><a href="/docs/validation.html">Validation</a></li>
-<li><a href="/docs/middleware.html">Middleware</a></li>
-<li><a href="/docs/populate.html">Populate</a></li>
-<li><a href="/docs/discriminators.html">Discriminators</a></li>
-<li><a href="/docs/plugins.html">Plugins</a></li>
-<li><a href="/docs/tutorials/lean.html">Faster Mongoose Queries With Lean</a></li>
-<li><a href="/docs/tutorials/query_casting.html">Query Casting</a></li>
-<li><a href="/docs/tutorials/findoneandupdate.html">findOneAndUpdate</a></li>
-</ul>
-<h3 id="integrations">Integrations</h3>
-<ul>
-<li><a href="/docs/customschematypes.html">Custom SchemaTypes</a></li>
-<li><a href="/docs/promises.html">Promises</a></li>
-<li><a href="/docs/lambda.html">AWS Lambda</a></li>
-<li><a href="/docs/browser.html">Browser Library</a></li>
-<li><a href="/docs/geojson.html">GeoJSON</a></li>
-<li><a href="/docs/transactions.html">Transactions</a></li>
-<li><a href="/docs/deprecations.html">MongoDB Driver Deprecation Warnings</a></li>
-<li><a href="/docs/jest.html">Testing with Jest</a></li>
-<li><a href="/docs/tutorials/dates.html">Working with Dates</a></li>
-</ul>
-<h3 id="migration-guides">Migration Guides</h3>
-<ul>
-<li><a href="/docs/migrating_to_5.html">Mongoose 4.x to 5.x</a></li>
-<li><a href="/docs/migration.html">Mongoose 3.x to 4.x</a></li>
-</ul>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/index.html b/docs/index.html
deleted file mode 100644
index 688c6d666a5..00000000000
--- a/docs/index.html
+++ /dev/null
@@ -1,128 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Getting Started</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><style>hr {
-  display: block;
-  margin-top: 40px;
-  margin-bottom: 40px;
-  border: 0px;
-  height: 1px;
-  background-color: #232323;
-  width: 100%;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="getting-started">Getting Started</h2>
-<p><em>First be sure you have <a href="http://www.mongodb.org/downloads">MongoDB</a> and <a href="http://nodejs.org/">Node.js</a> installed.</em></p>
-<p>Next install Mongoose from the command line using <code>npm</code>:</p>
-<pre><code>$ npm install mongoose</code></pre><p>Now say we like fuzzy kittens and want to record every kitten we ever meet
-in MongoDB.
-The first thing we need to do is include mongoose in our project and open a
-connection to the <code>test</code> database on our locally running instance of MongoDB.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// getting-started.js</span>
-<span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.connect(<span class="hljs-string">'mongodb://localhost/test'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});</code></pre>
-<p>We have a pending connection to the test database running on localhost.
-We now need to get notified if we connect successfully or if a connection
-error occurs:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> db = mongoose.connection;
-db.on(<span class="hljs-string">'error'</span>, <span class="hljs-built_in">console</span>.error.bind(<span class="hljs-built_in">console</span>, <span class="hljs-string">'connection error:'</span>));
-db.once(<span class="hljs-string">'open'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// we're connected!</span>
-});</code></pre>
-<p>Once our connection opens, our callback will be called. For brevity,
-let&#39;s assume that all following code is within this callback.</p>
-<p>With Mongoose, everything is derived from a <a href="/docs/guide.html">Schema</a>.
-Let&#39;s get a reference to it and define our kittens.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> kittySchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>
-});</code></pre>
-<p>So far so good. We&#39;ve got a schema with one property, <code>name</code>, which will be a  <code>String</code>. The next step is compiling our schema into a <a href="/docs/models.html">Model</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Kitten = mongoose.model(<span class="hljs-string">'Kitten'</span>, kittySchema);</code></pre>
-<p>A model is a class with which we construct documents.
-In this case, each document will be a kitten with properties and behaviors as declared in our schema.
-Let&#39;s create a kitten document representing the little guy we just met on the sidewalk outside:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> silence = <span class="hljs-keyword">new</span> Kitten({ name: <span class="hljs-string">'Silence'</span> });
-<span class="hljs-built_in">console</span>.log(silence.name); <span class="hljs-comment">// 'Silence'</span></code></pre>
-<p>Kittens can meow, so let&#39;s take a look at how to add &quot;speak&quot; functionality
-to our documents:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// <span class="hljs-doctag">NOTE:</span> methods must be added to the schema before compiling it with mongoose.model()</span>
-kittySchema.methods.speak = <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">var</span> greeting = <span class="hljs-keyword">this</span>.name
-    ? <span class="hljs-string">"Meow name is "</span> + <span class="hljs-keyword">this</span>.name
-    : <span class="hljs-string">"I don't have a name"</span>;
-  <span class="hljs-built_in">console</span>.log(greeting);
-}
-
-<span class="hljs-keyword">var</span> Kitten = mongoose.model(<span class="hljs-string">'Kitten'</span>, kittySchema);</code></pre>
-<p>Functions added to the <code>methods</code> property of a schema get compiled into
-the <code>Model</code> prototype and exposed on each document instance:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> fluffy = <span class="hljs-keyword">new</span> Kitten({ name: <span class="hljs-string">'fluffy'</span> });
-fluffy.speak(); <span class="hljs-comment">// "Meow name is fluffy"</span></code></pre>
-<p>We have talking kittens! But we still haven&#39;t saved anything to MongoDB.
-Each document can be saved to the database by calling its <a href="/docs/api.html#model_Model-save">save</a> method. The first argument to the callback will be an error if any occurred.</p>
-<pre><code class="language-javascript">  fluffy.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, fluffy</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> <span class="hljs-built_in">console</span>.error(err);
-    fluffy.speak();
-  });</code></pre>
-<p>Say time goes by and we want to display all the kittens we&#39;ve seen.
-We can access all of the kitten documents through our Kitten <a href="/docs/models.html">model</a>.</p>
-<pre><code class="language-javascript">Kitten.find(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, kittens</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> <span class="hljs-built_in">console</span>.error(err);
-  <span class="hljs-built_in">console</span>.log(kittens);
-})</code></pre>
-<p>We just logged all of the kittens in our db to the console.
-If we want to filter our kittens by name, Mongoose supports MongoDBs rich <a href="/docs/queries.html">querying</a> syntax.</p>
-<pre><code class="language-javascript">Kitten.find({ name: <span class="hljs-regexp">/^fluff/</span> }, callback);</code></pre>
-<p>This performs a search for all documents with a name property that begins
-with &quot;Fluff&quot; and returns the result as an array of kittens to the callback.</p>
-<h3 id="congratulations">Congratulations</h3>
-<p>That&#39;s the end of our quick start. We created a schema, added a custom document method, saved and queried kittens in MongoDB using Mongoose. Head over to the <a href="guide.html">guide</a>, or <a href="api.html">API docs</a> for more.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/jest.html b/docs/jest.html
deleted file mode 100644
index 3b25879653d..00000000000
--- a/docs/jest.html
+++ /dev/null
@@ -1,119 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Testing Mongoose with Jest</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="testing-mongoose-with-jest">Testing Mongoose with <a href="https://www.npmjs.com/package/jest">Jest</a></h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Jest is a client-side JavaScript testing library developed by Facebook.
-It was one of the libraries affected by <a href="https://www.theregister.co.uk/2017/09/22/facebook_will_free_react_other_code_from_unloved_license/">Facebook&#39;s licensing scandal in 2017</a>.
-Because Jest is designed primarily for testing React applications, using
-it to test Node.js server-side applications comes with a lot of caveats.
-We strongly recommend using <a href="http://npmjs.com/package/mocha">Mocha</a> instead.
-If you choose to delve into dangerous waters and test Mongoose apps with
-Jest, here&#39;s what you need to know:</p>
-<h2 id="recommended-testenvironment">Recommended <code>testEnvironment</code></h2>
-<p>Do <strong>not</strong> use Jest&#39;s default <a href="https://jestjs.io/docs/en/configuration.html#testenvironment-string"><code>jsdom</code> test environment</a>
-when testing Mongoose apps, <em>unless</em> you are explicitly testing an
-application that only uses
-<a href="https://mongoosejs.com/docs/browser.html">Mongoose&#39;s browser library</a>.</p>
-<p>The <code>jsdom</code> test environment attempts to create a browser-like test
-environment in Node.js, and it comes with numerous nasty surprises like a
-<a href="https://github.com/jsdom/jsdom/commit/3f306bea5362aceb2a219a2e98ff96a7464d2f19#commitcomment-31316213">stubbed <code>setTimeout()</code> function</a>
-that silently fails after tests are finished. Mongoose does not support jsdom
-in general and is not expected to function correctly in the <code>jsdom</code> test
-environment.</p>
-<p>To change your <code>testEnvironment</code> to Node.js, add <code>testEnvironment</code> to your
-<code>jest.config.js</code> file:</p>
-<pre><code class="language-javascript"><span class="hljs-built_in">module</span>.exports = {
-  testEnvironment: <span class="hljs-string">'node'</span>
-};</code></pre>
-<h2 id="timer-mocks">Timer Mocks</h2>
-<p>Absolutely do <strong>not</strong> use <a href="https://jestjs.io/docs/en/timer-mocks.html">timer mocks</a>
-when testing Mongoose apps. Fake timers stub out global functions like
-<code>setTimeout()</code> and <code>setInterval()</code>, which causes problems when an underlying
-library uses these functions. The MongoDB Node.js driver uses these functions
-for deferring work until the next tick of the event loop and for monitoring
-connections to the MongoDB server.</p>
-<p>Mongoose devs have already refactored out code
-to <a href="https://github.com/Automattic/mongoose/issues/6074">avoid using <code>setImmediate()</code></a>
-to defer work to the next tick of the event loop, but we can&#39;t reasonably
-ensure that every library Mongoose depends on doesn&#39;t use <code>setImmediate()</code>.</p>
-<p>Mongoose uses <code>nextTick()</code>, which <a href="https://sinonjs.org/releases/latest/fake-timers/">Jest&#39;s underlying dependency explicitly doesn&#39;t stub by default</a>.
-But, <code>process.nextTick()</code> isn&#39;t the same as <code>setImmediate()</code> because of
-<a href="https://abc.danch.me/microtasks-macrotasks-more-on-the-event-loop-881557d7af6f#2261">microtasks vs macrotasks</a>,
-so underlying libraries like the <a href="http://npmjs.com/package/mongodb">MongoDB driver</a> may use <code>setImmediate()</code>.</p>
-<p>To work around this, create your own wrapper around <code>setTimeout()</code> and
-stub that instead using <a href="http://npmjs.com/package/sinon">sinon</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// time.js</span>
-exports.setTimeout = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> global.setTimeout.apply(global, <span class="hljs-built_in">arguments</span>);
-};
-
-<span class="hljs-comment">// Tests</span>
-<span class="hljs-keyword">const</span> time = <span class="hljs-built_in">require</span>(<span class="hljs-string">'../util/time'</span>);
-<span class="hljs-keyword">const</span> sinon = <span class="hljs-built_in">require</span>(<span class="hljs-string">'sinon'</span>);
-sinon.stub(time, <span class="hljs-string">'setTimeout'</span>);</code></pre>
-<h2 id="further-reading">Further Reading</h2>
-<p>Want to learn more about testing Mongoose apps? The
-<a href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">RESTful Web Services with Node.js and Express</a>
-course on Pluralsight has a great section on testing Mongoose apps with <a href="http://npmjs.com/package/mocha">Mocha</a>.</p>
-<a href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">
-  <img src="https://i.imgur.com/KouuaAZ.png">
-</a></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/lambda.html b/docs/lambda.html
deleted file mode 100644
index 1b9556b305a..00000000000
--- a/docs/lambda.html
+++ /dev/null
@@ -1,122 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Using Mongoose With AWS Lambda</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2>Using Mongoose With AWS Lambda</h2><script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p><a href="https://aws.amazon.com/lambda/">AWS Lambda</a> is a popular service for running
-arbitrary functions without managing individual servers. Using Mongoose in your
-AWS Lambda functions is easy. Here&#39;s a sample function that connects to a
-MongoDB instance and finds a single document:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-
-<span class="hljs-keyword">let</span> conn = <span class="hljs-literal">null</span>;
-
-<span class="hljs-keyword">const</span> uri = <span class="hljs-string">'YOUR CONNECTION STRING HERE'</span>;
-
-exports.handler = <span class="hljs-keyword">async</span> <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">event, context</span>) </span>{
-  <span class="hljs-comment">// Make sure to add this so you can re-use `conn` between function calls.</span>
-  <span class="hljs-comment">// See https://www.mongodb.com/blog/post/serverless-development-with-nodejs-aws-lambda-mongodb-atlas</span>
-  context.callbackWaitsForEmptyEventLoop = <span class="hljs-literal">false</span>;
-
-  <span class="hljs-comment">// Because `conn` is in the global scope, Lambda may retain it between</span>
-  <span class="hljs-comment">// function calls thanks to `callbackWaitsForEmptyEventLoop`.</span>
-  <span class="hljs-comment">// This means your Lambda function doesn't have to go through the</span>
-  <span class="hljs-comment">// potentially expensive process of connecting to MongoDB every time.</span>
-  <span class="hljs-keyword">if</span> (conn == <span class="hljs-literal">null</span>) {
-    conn = <span class="hljs-keyword">await</span> mongoose.createConnection(uri, {
-      <span class="hljs-comment">// Buffering means mongoose will queue up operations if it gets</span>
-      <span class="hljs-comment">// disconnected from MongoDB and send them when it reconnects.</span>
-      <span class="hljs-comment">// With serverless, better to fail fast if not connected.</span>
-      bufferCommands: <span class="hljs-literal">false</span>, <span class="hljs-comment">// Disable mongoose buffering</span>
-      bufferMaxEntries: <span class="hljs-number">0</span> <span class="hljs-comment">// and MongoDB driver buffering</span>
-    });
-    conn.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-built_in">String</span> }));
-  }
-
-  <span class="hljs-keyword">const</span> M = conn.model(<span class="hljs-string">'Test'</span>);
-
-  <span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> M.findOne();
-  <span class="hljs-built_in">console</span>.log(doc);
-
-  <span class="hljs-keyword">return</span> doc;
-};</code></pre>
-<p>To import this function into Lambda, go <a href="https://console.aws.amazon.com/lambda">the AWS Lambda console</a>
-and click &quot;Create Function&quot;.</p>
-<p><a href="https://i.imgur.com/FlAD0vT.png"><img src="https://i.imgur.com/FlAD0vT.png"></a></p>
-<p>Create a function called &quot;mongoose-test&quot; with the below settings:</p>
-<p><a href="https://i.imgur.com/YOYJzeO.png"><img src="https://i.imgur.com/YOYJzeO.png"></a></p>
-<p>Copy the source code into a file called <code>lambda.js</code>. Then run <code>npm install mongoose co</code>.
-Finally, run <code>zip -r mongoose-test.zip node_modules/ lambda.js</code> to create a
-zip that you can upload to Lambda using the &quot;Upload a Zip File&quot; option under &quot;Function code&quot;.
-Make sure you also change the &quot;Handler&quot; input to <code>lambda.handler</code> to match the <code>lambda.js</code> file&#39;s <code>handler</code> function.</p>
-<p><a href="https://i.imgur.com/BXc9egq.png"><img src="https://i.imgur.com/BXc9egq.png"></a></p>
-<p>Next, click the &quot;Save&quot; button and then the &quot;Test&quot; button. The &quot;Test&quot; button will
-ask you to create a new test event, just create one because your inputs don&#39;t matter
-for this example. Then, hit &quot;Test&quot; again to actually run your function:</p>
-<p><a href="https://i.imgur.com/2UKtWYq.png"><img src="https://i.imgur.com/2UKtWYq.png"></a></p>
-<p>If your MongoDB database goes down in between function calls, you may
-see the below error message:</p>
-<pre><code>cannot find account after reload: could not find config <span class="hljs-keyword">for</span> &lt;hostname&gt;</code></pre><p>Lambda&#39;s JavaScript framework recently added support for
-async/await as long as you&#39;re using Node 8.x, so make sure you&#39;re not
-using Node.js 6.x.</p>
-<p><em>Want to learn how to check whether your favorite JavaScript frameworks, like <a href="http://expressjs.com/">Express</a> or <a href="https://reactjs.org/">React</a>, work with async/await? Spoiler alert: neither Express nor React support async/await. Chapter 4 of Mastering Async/Await explains the basic principles for determining whether a framework supports async/await. <a href="http://asyncawait.net/?utm_source=mongoosejs&amp;utm_campaign=lambda">Get your copy!</a></em></p>
-<a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=lambda" style="margin-left: 100px">
-  <img src="/docs/images/asyncawait.png" style="width: 650px" />
-</a></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/middleware.html b/docs/middleware.html
deleted file mode 100644
index ccb1cbcb8b8..00000000000
--- a/docs/middleware.html
+++ /dev/null
@@ -1,429 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Middleware</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="middleware">Middleware</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Middleware (also called pre and post <em>hooks</em>) are functions which are passed
-control during execution of asynchronous functions. Middleware is specified
-on the schema level and is useful for writing <a href="./plugins.html">plugins</a>.</p>
-<ul class="toc">
-  <li><a href="#types-of-middleware">Types of Middleware</a></li>
-  <li><a href="#pre">Pre</a></li>
-  <li><a href="#error-handling">Errors in Pre Hooks</a></li>
-  <li><a href="#post">Post</a></li>
-  <li><a href="#post-async">Asynchronous Post Hooks</a></li>
-  <li><a href="#order">Save/Validate Hooks</a></li>
-  <li><a href="#naming">Naming Conflicts</a></li>
-  <li><a href="#notes">Notes on findAndUpdate() and Query Middleware</a></li>
-  <li><a href="#error-handling-middleware">Error Handling Middleware</a></li>
-  <li><a href="#aggregate">Aggregation Hooks</a></li>
-  <li><a href="#synchronous">Synchronous Hooks</a></li>
-</ul>
-
-<h3 id="types-of-middleware">Types of Middleware</h3>
-<p>Mongoose has 4 types
-of middleware: document middleware, model middleware, aggregate middleware, and query middleware.
-Document middleware is supported for the following document functions.
-In document middleware functions, <code>this</code> refers to the document.</p>
-<ul>
-<li><a href="./api.html#document_Document-validate">validate</a></li>
-<li><a href="./api.html#model_Model-save">save</a></li>
-<li><a href="./api.html#model_Model-remove">remove</a></li>
-<li><a href="./api.html#document_Document-init">init</a> (note: init hooks are <a href="#synchronous">synchronous</a>)</li>
-</ul>
-<p>Query middleware is supported for the following Model and Query functions.
-In query middleware functions, <code>this</code> refers to the query.</p>
-<ul>
-<li><a href="./api.html#query_Query-count">count</a></li>
-<li><a href="./api.html#query_Query-deleteMany">deleteMany</a></li>
-<li><a href="./api.html#query_Query-deleteOne">deleteOne</a></li>
-<li><a href="./api.html#query_Query-find">find</a></li>
-<li><a href="./api.html#query_Query-findOne">findOne</a></li>
-<li><a href="./api.html#query_Query-findOneAndDelete">findOneAndDelete</a></li>
-<li><a href="./api.html#query_Query-findOneAndRemove">findOneAndRemove</a></li>
-<li><a href="./api.html#query_Query-findOneAndUpdate">findOneAndUpdate</a></li>
-<li><a href="./api.html#model_Model.remove">remove</a></li>
-<li><a href="./api.html#query_Query-update">update</a></li>
-<li><a href="./api.html#query_Query-updateOne">updateOne</a></li>
-<li><a href="./api.html#query_Query-updateMany">updateMany</a></li>
-</ul>
-<p>Aggregate middleware is for <code>MyModel.aggregate()</code>. Aggregate middleware
-executes when you call <code>exec()</code> on an aggregate object.
-In aggregate middleware, <code>this</code> refers to the <a href="./api.html#model_Model.aggregate">aggregation object</a>.</p>
-<ul>
-<li><a href="./api.html#model_Model.aggregate">aggregate</a></li>
-</ul>
-<p>Model middleware is supported for the following model functions.
-In model middleware functions, <code>this</code> refers to the model.</p>
-<ul>
-<li><a href="./api.html#model_Model.insertMany">insertMany</a></li>
-</ul>
-<p>All middleware types support pre and post hooks.
-How pre and post hooks work is described in more detail below.</p>
-<p><strong>Note:</strong> If you specify <code>schema.pre(&#39;remove&#39;)</code>, Mongoose will register this
-middleware for <a href="./api.html#model_Model-remove"><code>doc.remove()</code></a> by default. If you
-want to your middleware to run on <a href="./api.html#query_Query-remove"><code>Query.remove()</code></a>
-use <a href="./api.html#schema_Schema-pre"><code>schema.pre(&#39;remove&#39;, { query: true, document: false }, fn)</code></a>.</p>
-<p><strong>Note:</strong> The <a href="./api.html#model_Model.create"><code>create()</code></a> function fires <code>save()</code> hooks.</p>
-<h3 id="pre"><a href="#pre">Pre</a></h3>
-
-<p>Pre middleware functions are executed one after another, when each
-middleware calls <code>next</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema(..);
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-comment">// do stuff</span>
-  next();
-});</code></pre>
-<p>In <a href="http://thecodebarbarian.com/introducing-mongoose-5.html#promises-and-async-await-with-middleware">mongoose 5.x</a>, instead of calling <code>next()</code> manually, you can use a
-function that returns a promise. In particular, you can use <a href="http://thecodebarbarian.com/common-async-await-design-patterns-in-node.js.html"><code>async/await</code></a>.</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> doStuff().
-    then(() =&gt; doMoreStuff());
-});
-
-<span class="hljs-comment">// Or, in Node.js &gt;= 7.6.0:</span>
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-keyword">async</span> <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">await</span> doStuff();
-  <span class="hljs-keyword">await</span> doMoreStuff();
-});</code></pre>
-<p>If you use <code>next()</code>, the <code>next()</code> call does <strong>not</strong> stop the rest of the code in your middleware function from executing. Use
-<a href="https://www.bennadel.com/blog/2323-use-a-return-statement-when-invoking-callbacks-especially-in-a-guard-statement.htm">the early <code>return</code> pattern</a>
-to prevent the rest of your middleware function from running when you call <code>next()</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema(..);
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">if</span> (foo()) {
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'calling next!'</span>);
-    <span class="hljs-comment">// `return next();` will make sure the rest of this function doesn't run</span>
-    <span class="hljs-comment">/*return*/</span> next();
-  }
-  <span class="hljs-comment">// Unless you comment out the `return` above, 'after next' will print</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'after next'</span>);
-});</code></pre>
-<h4 id="use-cases">Use Cases</h4>
-
-<p>Middleware are useful for atomizing model logic. Here are some other ideas:</p>
-<ul>
-<li>complex validation</li>
-<li>removing dependent documents (removing a user removes all his blogposts)</li>
-<li>asynchronous defaults</li>
-<li>asynchronous tasks that a certain action triggers</li>
-</ul>
-<h4 id="error-handling">Errors in Pre Hooks</h4>
-
-<p>If any pre hook errors out, mongoose will not execute subsequent middleware
-or the hooked function. Mongoose will instead pass an error to the callback
-and/or reject the returned promise. There are several ways to report an
-error in middleware:</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">const</span> err = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'something went wrong'</span>);
-  <span class="hljs-comment">// If you call `next()` with an argument, that argument is assumed to be</span>
-  <span class="hljs-comment">// an error.</span>
-  next(err);
-});
-
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// You can also return a promise that rejects</span>
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Promise</span>((resolve, reject) =&gt; {
-    reject(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'something went wrong'</span>));
-  });
-});
-
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// You can also throw a synchronous error</span>
-  <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'something went wrong'</span>);
-});
-
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-keyword">async</span> <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">await</span> <span class="hljs-built_in">Promise</span>.resolve();
-  <span class="hljs-comment">// You can also throw an error in an `async` function</span>
-  <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'something went wrong'</span>);
-});
-
-<span class="hljs-comment">// later...</span>
-
-<span class="hljs-comment">// Changes will not be persisted to MongoDB because a pre hook errored out</span>
-myDoc.save(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(err.message); <span class="hljs-comment">// something went wrong</span>
-});</code></pre>
-<p>Calling <code>next()</code> multiple times is a no-op. If you call <code>next()</code> with an
-error <code>err1</code> and then throw an error <code>err2</code>, mongoose will report <code>err1</code>.</p>
-<h3 id="post"><a href="#post">Post middleware</a></h3>
-
-<p><a href="/docs/api.html#schema_Schema-post">post</a> middleware are executed <em>after</em>
-the hooked method and all of its <code>pre</code> middleware have completed.</p>
-<pre><code class="language-javascript">schema.post(<span class="hljs-string">'init'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s has been initialized from the db'</span>, doc._id);
-});
-schema.post(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s has been validated (but not saved yet)'</span>, doc._id);
-});
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s has been saved'</span>, doc._id);
-});
-schema.post(<span class="hljs-string">'remove'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s has been removed'</span>, doc._id);
-});</code></pre>
-<h3 id="post-async"><a href="#post-async">Asynchronous Post Hooks</a></h3>
-
-<p>If your post hook function takes at least 2 parameters, mongoose will
-assume the second parameter is a <code>next()</code> function that you will call to
-trigger the next middleware in the sequence.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Takes 2 parameters: this is an asynchronous post hook</span>
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc, next</span>) </span>{
-  setTimeout(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'post1'</span>);
-    <span class="hljs-comment">// Kick off the second post hook</span>
-    next();
-  }, <span class="hljs-number">10</span>);
-});
-
-<span class="hljs-comment">// Will not execute until the first middleware calls `next()`</span>
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc, next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'post2'</span>);
-  next();
-});</code></pre>
-<h3 id="order"><a href="#order">Save/Validate Hooks</a></h3>
-
-<p>The <code>save()</code> function triggers <code>validate()</code> hooks, because mongoose
-has a built-in <code>pre(&#39;save&#39;)</code> hook that calls <code>validate()</code>. This means
-that all <code>pre(&#39;validate&#39;)</code> and <code>post(&#39;validate&#39;)</code> hooks get called
-<strong>before</strong> any <code>pre(&#39;save&#39;)</code> hooks.</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'this gets printed first'</span>);
-});
-schema.post(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'this gets printed second'</span>);
-});
-schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'this gets printed third'</span>);
-});
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'this gets printed fourth'</span>);
-});</code></pre>
-<h3 id="naming"><a href="#naming">Naming Conflicts</a></h3>
-
-<p>Mongoose has both query and document hooks for <code>remove()</code>.</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'remove'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Removing!'</span>); });
-
-<span class="hljs-comment">// Prints "Removing!"</span>
-doc.remove();
-
-<span class="hljs-comment">// Does **not** print "Removing!". Query middleware for `remove` is not</span>
-<span class="hljs-comment">// executed by default.</span>
-Model.remove();</code></pre>
-<p>You can pass options to <a href="/docs/api.html#schema_Schema-pre"><code>Schema.pre()</code></a>
-and <a href="/docs/api.html#schema_Schema-post"><code>Schema.post()</code></a> to switch whether
-Mongoose calls your <code>remove()</code> hook for <a href="/docs/api.html#model_Model-remove"><code>Document.remove()</code></a>
-or <a href="/docs/api.html#model_Model.remove"><code>Model.remove()</code></a>:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Only document middleware</span>
-schema.pre(<span class="hljs-string">'remove'</span>, { <span class="hljs-built_in">document</span>: <span class="hljs-literal">true</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Removing doc!'</span>);
-});
-
-<span class="hljs-comment">// Only query middleware. This will get called when you do `Model.remove()`</span>
-<span class="hljs-comment">// but not `doc.remove()`.</span>
-schema.pre(<span class="hljs-string">'remove'</span>, { query: <span class="hljs-literal">true</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Removing!'</span>);
-});</code></pre>
-<h3 id="notes"><a href="#notes">Notes on findAndUpdate() and Query Middleware</a></h3>
-
-<p>Pre and post <code>save()</code> hooks are <strong>not</strong> executed on <code>update()</code>,
-<code>findOneAndUpdate()</code>, etc. You can see a more detailed discussion why in
-<a href="http://github.com/Automattic/mongoose/issues/964">this GitHub issue</a>.
-Mongoose 4.0 introduced distinct hooks for these functions.</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'find'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span> <span class="hljs-keyword">instanceof</span> mongoose.Query); <span class="hljs-comment">// true</span>
-  <span class="hljs-keyword">this</span>.start = <span class="hljs-built_in">Date</span>.now();
-});
-
-schema.post(<span class="hljs-string">'find'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">result</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">this</span> <span class="hljs-keyword">instanceof</span> mongoose.Query); <span class="hljs-comment">// true</span>
-  <span class="hljs-comment">// prints returned documents</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'find() returned '</span> + <span class="hljs-built_in">JSON</span>.stringify(result));
-  <span class="hljs-comment">// prints number of milliseconds the query took</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'find() took '</span> + (<span class="hljs-built_in">Date</span>.now() - <span class="hljs-keyword">this</span>.start) + <span class="hljs-string">' millis'</span>);
-});</code></pre>
-<p>Query middleware differs from document middleware in a subtle but
-important way: in document middleware, <code>this</code> refers to the document
-being updated. In query middleware, mongoose doesn&#39;t necessarily have
-a reference to the document being updated, so <code>this</code> refers to the
-<strong>query</strong> object rather than the document being updated.</p>
-<p>For instance, if you wanted to add an <code>updatedAt</code> timestamp to every
-<code>update()</code> call, you would use the following pre hook.</p>
-<pre><code class="language-javascript">schema.pre(<span class="hljs-string">'update'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">this</span>.update({},{ $set: { updatedAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>() } });
-});</code></pre>
-<h3 id="error-handling-middleware"><a href="#error-handling-middleware">Error Handling Middleware</a></h3>
-
-<p><em>New in 4.5.0</em></p>
-<p>Middleware execution normally stops the first time a piece of middleware
-calls <code>next()</code> with an error. However, there is a special kind of post
-middleware called &quot;error handling middleware&quot; that executes specifically
-when an error occurs. Error handling middleware is useful for reporting
-errors and making error messages more readable.</p>
-<p>Error handling middleware is defined as middleware that takes one extra
-parameter: the &#39;error&#39; that occurred as the first parameter to the function.
-Error handling middleware can then transform the error however you want.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name: {
-    type: <span class="hljs-built_in">String</span>,
-    <span class="hljs-comment">// Will trigger a MongoError with code 11000 when</span>
-    <span class="hljs-comment">// you save a duplicate</span>
-    unique: <span class="hljs-literal">true</span>
-  }
-});
-
-<span class="hljs-comment">// Handler **must** take 3 parameters: the error that occurred, the document</span>
-<span class="hljs-comment">// in question, and the `next()` function</span>
-schema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, doc, next</span>) </span>{
-  <span class="hljs-keyword">if</span> (error.name === <span class="hljs-string">'MongoError'</span> &amp;&amp; error.code === <span class="hljs-number">11000</span>) {
-    next(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'There was a duplicate key error'</span>));
-  } <span class="hljs-keyword">else</span> {
-    next();
-  }
-});
-
-<span class="hljs-comment">// Will trigger the `post('save')` error handler</span>
-Person.create([{ name: <span class="hljs-string">'Axl Rose'</span> }, { name: <span class="hljs-string">'Axl Rose'</span> }]);</code></pre>
-<p>Error handling middleware also works with query middleware. You can
-also define a post <code>update()</code> hook that will catch MongoDB duplicate key
-errors.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// The same E11000 error can occur when you call `update()`</span>
-<span class="hljs-comment">// This function **must** take 3 parameters. If you use the</span>
-<span class="hljs-comment">// `passRawResult` function, this function **must** take 4</span>
-<span class="hljs-comment">// parameters</span>
-schema.post(<span class="hljs-string">'update'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, res, next</span>) </span>{
-  <span class="hljs-keyword">if</span> (error.name === <span class="hljs-string">'MongoError'</span> &amp;&amp; error.code === <span class="hljs-number">11000</span>) {
-    next(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'There was a duplicate key error'</span>));
-  } <span class="hljs-keyword">else</span> {
-    next(); <span class="hljs-comment">// The `update()` call will still error out.</span>
-  }
-});
-
-<span class="hljs-keyword">var</span> people = [{ name: <span class="hljs-string">'Axl Rose'</span> }, { name: <span class="hljs-string">'Slash'</span> }];
-Person.create(people, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  Person.update({ name: <span class="hljs-string">'Slash'</span> }, { $set: { name: <span class="hljs-string">'Axl Rose'</span> } }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-    <span class="hljs-comment">// `error.message` will be "There was a duplicate key error"</span>
-  });
-});</code></pre>
-<p>Error handling middleware can transform an error, but it can&#39;t remove the
-error. Even if you call <code>next()</code> with no error as shown above, the
-function call will still error out.</p>
-<h3 id="aggregate"><a href="#aggregate">Aggregation Hooks</a></h3>
-
-<p>You can also define hooks for the <a href="api.html#model_Model.aggregate"><code>Model.aggregate()</code> function</a>.
-In aggregation middleware functions, <code>this</code> refers to the <a href="api.html#Aggregate">Mongoose <code>Aggregate</code> object</a>.
-For example, suppose you&#39;re implementing soft deletes on a <code>Customer</code> model
-by adding an <code>isDeleted</code> property. To make sure <code>aggregate()</code> calls only look
-at customers that aren&#39;t soft deleted, you can use the below middleware to
-add a <a href="api.html#aggregate_Aggregate-match"><code>$match</code> stage</a> to the beginning
-of each <a href="https://docs.mongodb.com/manual/core/aggregation-pipeline/">aggregation pipeline</a>.</p>
-<pre><code class="language-javascript">customerSchema.pre(<span class="hljs-string">'aggregate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Add a $match state to the beginning of each pipeline.</span>
-  <span class="hljs-keyword">this</span>.pipeline().unshift({ $match: { isDeleted: { $ne: <span class="hljs-literal">true</span> } } });
-});</code></pre>
-<p>The <a href="api.html#aggregate_Aggregate-pipeline"><code>Aggregate#pipeline()</code> function</a>
-lets you access the MongoDB aggregation pipeline that Mongoose will send to
-the MongoDB server. It is useful for adding stages to the beginning of the
-pipeline from middleware.</p>
-<h3 id="synchronous"><a href="#synchronous">Synchronous Hooks</a></h3>
-
-<p>Certain Mongoose hooks are synchronous, which means they do <strong>not</strong> support
-functions that return promises or receive a <code>next()</code> callback. Currently,
-only <code>init</code> hooks are synchronous, because the <a href="./api.html#document_Document-init"><code>init()</code> function</a>
-is synchronous. Below is an example of using pre and post init hooks.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ title: <span class="hljs-built_in">String</span>, loadedAt: <span class="hljs-built_in">Date</span> });
-
-schema.pre(<span class="hljs-string">'init'</span>, pojo =&gt; {
-  assert.equal(pojo.constructor.name, <span class="hljs-string">'Object'</span>); <span class="hljs-comment">// Plain object before init</span>
-});
-
-<span class="hljs-keyword">const</span> now = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>();
-schema.post(<span class="hljs-string">'init'</span>, doc =&gt; {
-  assert.ok(doc <span class="hljs-keyword">instanceof</span> mongoose.Document); <span class="hljs-comment">// Mongoose doc after init</span>
-  doc.loadedAt = now;
-});
-
-<span class="hljs-keyword">const</span> Test = db.model(<span class="hljs-string">'TestPostInitMiddleware'</span>, schema);
-
-<span class="hljs-keyword">return</span> Test.create({ title: <span class="hljs-string">'Casino Royale'</span> }).
-  then(doc =&gt; Test.findById(doc)).
-  then(doc =&gt; assert.equal(doc.loadedAt.valueOf(), now.valueOf()));</code></pre>
-<p>To report an error in an init hook, you must throw a <strong>synchronous</strong> error.
-Unlike all other middleware, init middleware does <strong>not</strong> handle promise
-rejections.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ title: <span class="hljs-built_in">String</span> });
-
-<span class="hljs-keyword">const</span> swallowedError = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'will not show'</span>);
-<span class="hljs-comment">// init hooks do **not** handle async errors or any sort of async behavior</span>
-schema.pre(<span class="hljs-string">'init'</span>, () =&gt; <span class="hljs-built_in">Promise</span>.reject(swallowedError));
-schema.post(<span class="hljs-string">'init'</span>, () =&gt; { <span class="hljs-keyword">throw</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'will show'</span>); });
-
-<span class="hljs-keyword">const</span> Test = db.model(<span class="hljs-string">'PostInitBook'</span>, schema);
-
-<span class="hljs-keyword">return</span> Test.create({ title: <span class="hljs-string">'Casino Royale'</span> }).
-  then(doc =&gt; Test.findById(doc)).
-  <span class="hljs-keyword">catch</span>(error =&gt; assert.equal(error.message, <span class="hljs-string">'will show'</span>));</code></pre>
-<h3 id="next">Next Up</h3>
-
-<p>Now that we&#39;ve covered middleware, let&#39;s take a look at Mongoose&#39;s approach
-to faking JOINs with its query <a href="/docs/populate.html">population</a> helper.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/migrating_to_5.html b/docs/migrating_to_5.html
deleted file mode 100644
index 72098c9fd83..00000000000
--- a/docs/migrating_to_5.html
+++ /dev/null
@@ -1,493 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Migrating to Mongoose 5</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><style>table td {
-  padding-right: 15px;
-}
-</style><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="migrating-from-4x-to-5x">Migrating from 4.x to 5.x</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>There are several <a href="https://github.com/Automattic/mongoose/blob/master/History.md">backwards-breaking changes</a>
-you should be aware of when migrating from Mongoose 4.x to Mongoose 5.x.</p>
-<p>If you&#39;re still on Mongoose 3.x, please read the <a href="migration.html">Mongoose 3.x to 4.x migration guide</a>.</p>
-<ul>
-<li><a href="#version-requirements">Version Requirements</a></li>
-<li><a href="#query-middleware">Query Middleware</a></li>
-<li><a href="#promises-and-callbacks">Promises and Callbacks for <code>mongoose.connect()</code></a></li>
-<li><a href="#connection-logic">Connection Logic and <code>useMongoClient</code></a></li>
-<li><a href="#setter-order">Setter Order</a></li>
-<li><a href="#id-getter">Checking if a path is populated</a></li>
-<li><a href="#return-value-for-delete">Return Values for <code>remove()</code> and <code>deleteX()</code></a></li>
-<li><a href="#aggregation-cursors">Aggregation Cursors</a></li>
-<li><a href="#geonear">geoNear</a></li>
-<li><a href="#uri-encoding">Required URI encoding of connection strings</a></li>
-<li><a href="#password-characters">Passwords which contain certain characters</a></li>
-<li><a href="#domain-sockets">Domain sockets</a></li>
-<li><a href="#toobject-options"><code>toObject()</code> Options</a></li>
-<li><a href="#aggregate-parameters">Aggregate Parameters</a></li>
-<li><a href="#boolean-casting">Boolean Casting</a></li>
-<li><a href="#query-casting">Query Casting</a></li>
-<li><a href="#post-save-flow-control">Post Save Hooks Get Flow Control</a></li>
-<li><a href="#pushall">The <code>$pushAll</code> Operator</a></li>
-<li><a href="#retain-key-order">Always Use Forward Key Order</a></li>
-<li><a href="#run-setters-on-queries">Run setters on queries</a></li>
-<li><a href="#browser-bundle">Pre-compiled Browser Bundle</a></li>
-<li><a href="#save-errors">Save Errors</a></li>
-<li><a href="#init-hooks">Init hook signatures</a></li>
-<li><a href="#save-num-affected"><code>numAffected</code> and <code>save()</code></a></li>
-<li><a href="#remove-debounce"><code>remove()</code> and debouncing</a></li>
-<li><a href="#get-promise-constructor"><code>getPromiseConstructor()</code></a></li>
-<li><a href="#pre-hook-params">Passing Parameters from Pre Hooks</a></li>
-<li><a href="#array-required"><code>required</code> validator for arrays</a></li>
-<li><a href="#debug-output">debug output defaults to stdout instead of stderr</a></li>
-<li><a href="#overwrite-filter">Overwriting filter properties</a></li>
-<li><a href="#bulkwrite-results"><code>bulkWrite()</code> results</a></li>
-</ul>
-<h3 id="version-requirements"><a href="#version-requirements">Version Requirements</a></h3>
-
-<p>Mongoose now requires Node.js &gt;= 4.0.0 and MongoDB &gt;= 3.0.0.
-<a href="https://www.mongodb.com/blog/post/mongodb-2-6-end-of-life">MongoDB 2.6</a> and
-<a href="https://github.com/nodejs/Release">Node.js &lt; 4</a> where both EOL-ed in 2016.</p>
-<h3 id="query-middleware"><a href="#query-middleware">Query Middleware</a></h3>
-
-<p>Query middleware is now compiled when you call <code>mongoose.model()</code> or <code>db.model()</code>. If you add query middleware after calling <code>mongoose.model()</code>, that middleware will <strong>not</strong> get called.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-schema.pre(<span class="hljs-string">'find'</span>, () =&gt; { <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'find!'</span>); });
-
-MyModel.find().exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// In mongoose 4.x, the above `.find()` will print "find!"</span>
-  <span class="hljs-comment">// In mongoose 5.x, "find!" will **not** be printed.</span>
-  <span class="hljs-comment">// Call `pre('find')` **before** calling `mongoose.model()` to make the middleware apply.</span>
-});</code></pre>
-<h3 id="promises-and-callbacks"><a href="#promises-and-callbacks">
-  Promises and Callbacks for `mongoose.connect()`
-</a></h3>
-
-<p><code>mongoose.connect()</code> and <code>mongoose.disconnect()</code> now return a promise if no callback specified, or <code>null</code> otherwise. It does <strong>not</strong> return the mongoose singleton.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Worked in mongoose 4. Does **not** work in mongoose 5, `mongoose.connect()`</span>
-<span class="hljs-comment">// now returns a promise consistently. This is to avoid the horrible things</span>
-<span class="hljs-comment">// we've done to allow mongoose to be a thenable that resolves to itself.</span>
-mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/test'</span>).model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({}));
-
-<span class="hljs-comment">// Do this instead</span>
-mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/test'</span>);
-mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({}));</code></pre>
-<h3 id="connection-logic"><a href="#connection-logic">
-  Connection Logic and `useMongoClient`
-</a></h3>
-
-<p>The <a href="http://mongoosejs.com/docs/4.x/docs/connections.html#use-mongo-client"><code>useMongoClient</code> option</a> was
-removed in Mongoose 5, it is now always <code>true</code>. As a consequence, Mongoose 5
-no longer supports several function signatures for <code>mongoose.connect()</code> that
-worked in Mongoose 4.x if the <code>useMongoClient</code> option was off. Below are some
-examples of <code>mongoose.connect()</code> calls that do <strong>not</strong> work in Mongoose 5.x.</p>
-<ul>
-<li><code>mongoose.connect(&#39;localhost&#39;, 27017);</code></li>
-<li><code>mongoose.connect(&#39;localhost&#39;, &#39;mydb&#39;, 27017);</code></li>
-<li><code>mongoose.connect(&#39;mongodb://host1:27017,mongodb://host2:27017&#39;);</code></li>
-</ul>
-<p>In Mongoose 5.x, the first parameter to <code>mongoose.connect()</code> and <code>mongoose.createConnection()</code>, if specified, <strong>must</strong> be a <a href="https://docs.mongodb.com/manual/reference/connection-string/">MongoDB connection string</a>. The
-connection string and options are then passed down to <a href="http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#.connect">the MongoDB Node.js driver&#39;s <code>MongoClient.connect()</code> function</a>. Mongoose does not modify the connection string, although <code>mongoose.connect()</code> and <code>mongoose.createConnection()</code> support a <a href="http://mongoosejs.com/docs/connections.html#options">few additional options in addition to the ones the MongoDB driver supports</a>.</p>
-<h3 id="setter-order"><a href="#setter-order">
-  Setter Order
-</a></h3>
-
-<p>Setters run in reverse order in 4.x:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>).
-  set(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'This will print 2nd'</span>)).
-  set(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'This will print first'</span>));</code></pre>
-<p>In 5.x, setters run in the order they&#39;re declared.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>).
-  set(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'This will print first'</span>)).
-  set(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'This will print 2nd'</span>));</code></pre>
-<h3 id="id-getter"><a href="#id-getter">
-  Checking if a path is populated
-</a></h3>
-
-<p>Mongoose 5.1.0 introduced an <code>_id</code> getter to ObjectIds that lets you get an ObjectId regardless of whether a path
-is populated.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> blogPostSchema = <span class="hljs-keyword">new</span> Schema({
-  title: <span class="hljs-built_in">String</span>,
-  author: {
-    type: mongoose.Schema.Types.ObjectId,
-    ref: <span class="hljs-string">'Author'</span>
-  }
-});
-<span class="hljs-keyword">const</span> BlogPost = mongoose.model(<span class="hljs-string">'BlogPost'</span>, blogPostSchema);
-
-<span class="hljs-keyword">await</span> BlogPost.create({ title: <span class="hljs-string">'test'</span>, author: author._id });
-<span class="hljs-keyword">const</span> blogPost = <span class="hljs-keyword">await</span> BlogPost.findOne();
-
-<span class="hljs-built_in">console</span>.log(blogPost.author); <span class="hljs-comment">// '5b207f84e8061d1d2711b421'</span>
-<span class="hljs-comment">// New in Mongoose 5.1.0: this will print '5b207f84e8061d1d2711b421' as well</span>
-<span class="hljs-built_in">console</span>.log(blogPost.author._id);
-
-<span class="hljs-keyword">await</span> blogPost.populate(<span class="hljs-string">'author'</span>);
-<span class="hljs-built_in">console</span>.log(blogPost.author._id); <span class="hljs-string">'5b207f84e8061d1d2711b421'</span></code></pre>
-<p>As a consequence, checking whether <code>blogPost.author._id</code> is <a href="https://github.com/Automattic/mongoose/issues/6415#issuecomment-388579185">no longer viable as a way to check whether <code>author</code> is populated</a>. Use <code>blogPost.populated(&#39;author&#39;) != null</code> or <code>blogPost.author instanceof mongoose.Types.ObjectId</code> to check whether <code>author</code> is populated instead.</p>
-<p>Note that you can call <code>mongoose.set(&#39;objectIdGetter&#39;, false)</code> to change this behavior.</p>
-<h3 id="return-value-for-delete"><a href="#return-value-for-delete">
-  Return Values for `remove()` and `deleteX()`
-</a></h3>
-
-<p><code>deleteOne()</code>, <code>deleteMany()</code>, and <code>remove()</code> now resolve to the result object
-rather than the full <a href="http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~writeOpCallback">driver <code>WriteOpResult</code> object</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// In 4.x, this is how you got the number of documents deleted</span>
-MyModel.deleteMany().then(res =&gt; <span class="hljs-built_in">console</span>.log(res.result.n));
-<span class="hljs-comment">// In 5.x this is how you get the number of documents deleted</span>
-MyModel.deleteMany().then(res =&gt; res.n);</code></pre>
-<h3 id="aggregation-cursors"><a href="#aggregation-cursors">
-  Aggregation Cursors
-</a></h3>
-
-<p>The <code>useMongooseAggCursor</code> option from 4.x is now always on. This is the new syntax for aggregation cursors in mongoose 5:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// When you call `.cursor()`, `.exec()` will now return a mongoose aggregation</span>
-<span class="hljs-comment">// cursor.</span>
-<span class="hljs-keyword">const</span> cursor = MyModel.aggregate([{ $match: { name: <span class="hljs-string">'Val'</span> } }]).cursor().exec();
-<span class="hljs-comment">// No need to `await` on the cursor or wait for a promise to resolve</span>
-cursor.eachAsync(doc =&gt; <span class="hljs-built_in">console</span>.log(doc));
-
-<span class="hljs-comment">// Can also pass options to `cursor()`</span>
-<span class="hljs-keyword">const</span> cursorWithOptions = MyModel.
-  aggregate([{ $match: { name: <span class="hljs-string">'Val'</span> } }]).
-  cursor({ batchSize: <span class="hljs-number">10</span> }).
-  exec();</code></pre>
-<h3 id="geonear"><a href="#geonear">
-  geoNear
-</a></h3>
-
-<p><code>Model.geoNear()</code> has been removed because the <a href="https://github.com/mongodb/node-mongodb-native/blob/master/CHANGES_3.0.0.md#geonear-command-helper">MongoDB driver no longer supports it</a></p>
-<h3 id="uri-encoding"><a href="#uri-encoding">
-  Required URI encoding of connection strings
-</a></h3>
-
-<p>Due to changes in the MongoDB driver, connection strings must be URI encoded.</p>
-<p>If they are not, connections may fail with an illegal character message.</p>
-<h3 id="password-characters"><a href="#password-characters">
-  Passwords which contain certain characters
-</a></h3>
-
-<p>See a <a href="https://developer.mozilla.org/en-US/docs/Glossary/percent-encoding">full list of affected characters</a>.</p>
-<p>If your app is used by a lot of different connection strings, it&#39;s possible
-that your test cases will pass, but production passwords will fail. Encode all your connection
-strings to be safe.</p>
-<p>If you want to continue to use unencoded connection strings, the easiest fix is to use
-the <code>mongodb-uri</code> module to parse the connection strings, and then produce the properly encoded
-versions. You can use a function like this:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> uriFormat = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongodb-uri'</span>)
-<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">encodeMongoURI</span> (<span class="hljs-params">urlString</span>) </span>{
-    <span class="hljs-keyword">if</span> (urlString) {
-      <span class="hljs-keyword">let</span> parsed = uriFormat.parse(urlString)
-      urlString = uriFormat.format(parsed);
-    }
-    <span class="hljs-keyword">return</span> urlString;
-  }
-}
-
-<span class="hljs-comment">// Your un-encoded string.</span>
-<span class="hljs-keyword">const</span> mongodbConnectString = <span class="hljs-string">"mongodb://..."</span>;
-mongoose.connect(encodeMongoURI(mongodbConnectString))</code></pre>
-<p>The function above is safe to use whether the existing string is already encoded or not.</p>
-<h3 id="domain-sockets"><a href="#domain-sockets">
-  Domain sockets
-</a></h3>
-
-<p>Domain sockets must be URI encoded. For example:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Works in mongoose 4. Does **not** work in mongoose 5 because of more</span>
-<span class="hljs-comment">// stringent URI parsing.</span>
-<span class="hljs-keyword">const</span> host = <span class="hljs-string">'/tmp/mongodb-27017.sock'</span>;
-mongoose.createConnection(<span class="hljs-string">`mongodb://aaron:psw@<span class="hljs-subst">${host}</span>/fake`</span>);
-
-<span class="hljs-comment">// Do this instead</span>
-<span class="hljs-keyword">const</span> host = <span class="hljs-built_in">encodeURIComponent</span>(<span class="hljs-string">'/tmp/mongodb-27017.sock'</span>);
-mongoose.createConnection(<span class="hljs-string">`mongodb://aaron:psw@<span class="hljs-subst">${host}</span>/fake`</span>);</code></pre>
-<h3 id="toobject-options"><a href="#toobject-options">
-  `toObject()` Options
-</a></h3>
-
-<p>The <code>options</code> parameter to <code>toObject()</code> and <code>toJSON()</code> merge defaults rather than overwriting them.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Note the `toObject` option below</span>
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }, { toObject: { virtuals: <span class="hljs-literal">true</span> } });
-schema.virtual(<span class="hljs-string">'answer'</span>).get(() =&gt; <span class="hljs-number">42</span>);
-<span class="hljs-keyword">const</span> MyModel = db.model(<span class="hljs-string">'MyModel'</span>, schema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> MyModel({ name: <span class="hljs-string">'test'</span> });
-<span class="hljs-comment">// In mongoose 4.x this prints "undefined", because `{ minimize: false }`</span>
-<span class="hljs-comment">// overwrites the entire schema-defined options object.</span>
-<span class="hljs-comment">// In mongoose 5.x this prints "42", because `{ minimize: false }` gets</span>
-<span class="hljs-comment">// merged with the schema-defined options.</span>
-<span class="hljs-built_in">console</span>.log(doc.toJSON({ minimize: <span class="hljs-literal">false</span> }).answer);</code></pre>
-<h3 id="aggregate-parameters"><a href="#aggregate-parameters">
-  Aggregate Parameters
-</a></h3>
-
-<p><code>aggregate()</code> no longer accepts a spread, you <strong>must</strong> pass your aggregation pipeline as an array. The below code worked in 4.x:</p>
-<pre><code class="language-javascript">MyModel.aggregate({ $match: { isDeleted: <span class="hljs-literal">false</span> } }, { $skip: <span class="hljs-number">10</span> }).exec(cb);</code></pre>
-<p>The above code does <strong>not</strong> work in 5.x, you <strong>must</strong> wrap the <code>$match</code> and <code>$skip</code> stages in an array.</p>
-<pre><code class="language-javascript">MyModel.aggregate([{ $match: { isDeleted: <span class="hljs-literal">false</span> } }, { $skip: <span class="hljs-number">10</span> }]).exec(cb);</code></pre>
-<h3 id="boolean-casting"><a href="#boolean-casting">
-  Boolean Casting
-</a></h3>
-
-<p>By default, mongoose 4 would coerce any value to a boolean without error.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Fine in mongoose 4, would save a doc with `boolField = true`</span>
-<span class="hljs-keyword">const</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({
-  boolField: <span class="hljs-built_in">Boolean</span>
-}));
-
-MyModel.create({ boolField: <span class="hljs-string">'not a boolean'</span> });</code></pre>
-<p>Mongoose 5 only casts the following values to <code>true</code>:</p>
-<ul>
-<li><code>true</code></li>
-<li><code>&#39;true&#39;</code></li>
-<li><code>1</code></li>
-<li><code>&#39;1&#39;</code></li>
-<li><code>&#39;yes&#39;</code></li>
-</ul>
-<p>And the following values to <code>false</code>:</p>
-<ul>
-<li><code>false</code></li>
-<li><code>&#39;false&#39;</code></li>
-<li><code>0</code></li>
-<li><code>&#39;0&#39;</code></li>
-<li><code>&#39;no&#39;</code></li>
-</ul>
-<p>All other values will cause a <code>CastError</code></p>
-<h3 id="query-casting"><a href="#query-casting">
-  Query Casting
-</a></h3>
-
-<p>Casting for <code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>, <code>replaceOne()</code>,
-<code>remove()</code>, <code>deleteOne()</code>, and <code>deleteMany()</code> doesn&#39;t happen until <code>exec()</code>.
-This makes it easier for hooks and custom query helpers to modify data, because
-mongoose won&#39;t restructure the data you passed in until after your hooks and
-query helpers have ran. It also makes it possible to set the <code>overwrite</code> option
-<em>after</em> passing in an update.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// In mongoose 4.x, this becomes `{ $set: { name: 'Baz' } }` despite the `overwrite`</span>
-<span class="hljs-comment">// In mongoose 5.x, this overwrite is respected and the first document with</span>
-<span class="hljs-comment">// `name = 'Bar'` will be replaced with `{ name: 'Baz' }`</span>
-User.where({ name: <span class="hljs-string">'Bar'</span> }).update({ name: <span class="hljs-string">'Baz'</span> }).setOptions({ overwrite: <span class="hljs-literal">true</span> });</code></pre>
-<h3 id="post-save-flow-control"><a href="#post-save-flow-control">
-  Post Save Hooks Get Flow Control
-</a></h3>
-
-<p>Post hooks now get flow control, which means async post save hooks and child document post save hooks execute <strong>before</strong> your <code>save()</code> callback.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> ChildModelSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  text: {
-    type: <span class="hljs-built_in">String</span>
-  }
-});
-ChildModelSchema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-comment">// In mongoose 5.x this will print **before** the `console.log()`</span>
-  <span class="hljs-comment">// in the `save()` callback. In mongoose 4.x this was reversed.</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Child post save'</span>);
-});
-<span class="hljs-keyword">const</span> ParentModelSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  children: [ChildModelSchema]
-});
-
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Parent'</span>, ParentModelSchema);
-<span class="hljs-keyword">const</span> m = <span class="hljs-keyword">new</span> Model({ children: [{ text: <span class="hljs-string">'test'</span> }] });
-m.save(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// In mongoose 5.xm this prints **after** the "Child post save" message.</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Save callback'</span>);
-});</code></pre>
-<h3 id="pushall"><a href="#pushall">
-  The `$pushAll` Operator
-</a></h3>
-
-<p><code>$pushAll</code> is no longer supported and no longer used internally for <code>save()</code>, since it has been <a href="https://docs.mongodb.com/manual/reference/operator/update/pushAll/">deprecated since MongoDB 2.4</a>. Use <code>$push</code> with <code>$each</code> instead.</p>
-<h3 id="retain-key-order"><a href="#retain-key-order">
-  Always Use Forward Key Order
-</a></h3>
-
-<p>The <code>retainKeyOrder</code> option was removed, mongoose will now always retain the same key position when cloning objects. If you have queries or indexes that rely on reverse key order, you will have to change them.</p>
-<h3 id="run-setters-on-queries"><a href="#run-setters-on-queries">
-  Run setters on queries
-</a></h3>
-
-<p>Setters now run on queries by default, and the old <code>runSettersOnQuery</code> option
-has been removed.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  email: { type: <span class="hljs-built_in">String</span>, lowercase: <span class="hljs-literal">true</span> }
-});
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-Model.find({ email: <span class="hljs-string">'FOO@BAR.BAZ'</span> }); <span class="hljs-comment">// Converted to `find({ email: 'foo@bar.baz' })`</span></code></pre>
-<h3 id="browser-bundle"><a href="#browser-bundle">
-  Pre-compiled Browser Bundle
-</a></h3>
-
-<p>We no longer have a pre-compiled version of mongoose for the browser. If you want to use mongoose schemas in the browser, you need to build your own bundle with browserify/webpack.</p>
-<h3 id="save-errors"><a href="#save-errors">
-  Save Errors
-</a></h3>
-
-<p>The <code>saveErrorIfNotFound</code> option was removed, mongoose will now always error out from <code>save()</code> if the underlying document was not found</p>
-<h3 id="init-hooks"><a href="#init-hooks">
-  Init hook signatures
-</a></h3>
-
-<p><code>init</code> hooks are now fully synchronous and do not receive <code>next()</code> as a parameter.</p>
-<p><code>Document.prototype.init()</code> no longer takes a callback as a parameter. It
-was always synchronous, just had a callback for legacy reasons.</p>
-<h3 id="save-num-affected"><a href="#save-num-affected">
-  `numAffected` and `save()`
-</a></h3>
-
-<p><code>doc.save()</code> no longer passes <code>numAffected</code> as a 3rd param to its callback.</p>
-<h3 id="remove-debounce"><a href="#remove-debounce">
-  `remove()` and debouncing
-</a></h3>
-
-<p><code>doc.remove()</code> no longer debounces</p>
-<h3 id="get-promise-constructor"><a href="#get-promise-constructor">
-  `getPromiseConstructor()`
-</a></h3>
-
-<p><code>getPromiseConstructor()</code> is gone, just use <code>mongoose.Promise</code>.</p>
-<h3 id="pre-hook-params"><a href="#pre-hook-params">
-  Passing Parameters from Pre Hooks
-</a></h3>
-
-<p>You cannot pass parameters to the next pre middleware in the chain using <code>next()</code> in mongoose 5.x. In mongoose 4, <code>next(&#39;Test&#39;)</code> in pre middleware would call the
-next middleware with &#39;Test&#39; as a parameter. Mongoose 5.x has removed support for this.</p>
-<h3 id="array-required"><a href="#array-required">
-  `required` validator for arrays
-</a></h3>
-
-<p>In mongoose 5 the <code>required</code> validator only verifies if the value is an
-array. That is, it will <strong>not</strong> fail for <em>empty</em> arrays as it would in
-mongoose 4.</p>
-<h3 id="debug-output"><a href="#debug-output">
-  debug output defaults to stdout instead of stderr
-</a></h3>
-
-<p>In mongoose 5 the default debug function uses <code>console.info()</code> to display messages instead of <code>console.error()</code>.</p>
-<h3 id="overwrite-filter"><a href="#overwrite-filter">
-  Overwriting filter properties
-</a></h3>
-
-<p>In Mongoose 4.x, overwriting a filter property that&#39;s a primitive with one that is an object would silently fail. For example, the below code would ignore the <code>where()</code> and be equivalent to <code>Sport.find({ name: &#39;baseball&#39; })</code></p>
-<pre><code class="language-javascript">Sport.find({ name: <span class="hljs-string">'baseball'</span> }).where({name: {$ne: <span class="hljs-string">'softball'</span>}});</code></pre>
-<p>In Mongoose 5.x, the above code will correctly overwrite <code>&#39;baseball&#39;</code> with <code>{ $ne: &#39;softball&#39; }</code> </p>
-<h3 id="bulkwrite-results"><a href="#bulkwrite-results">
-  `bulkWrite()` results
-</a></h3>
-
-<p>Mongoose 5.x uses version 3.x of the <a href="http://npmjs.com/package/mongodb">MongoDB Node.js driver</a>. MongoDB driver 3.x changed the format of
-the result of <a href="http://localhost:8088/docs/api.html#model_Model.bulkWrite"><code>bulkWrite()</code> calls</a> so there is no longer a top-level <code>nInserted</code>, <code>nModified</code>, etc. property. The new result object structure is <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult">described here</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-
-<span class="hljs-keyword">const</span> res = <span class="hljs-keyword">await</span> Model.bulkWrite([{ insertOne: { <span class="hljs-built_in">document</span>: { name: <span class="hljs-string">'test'</span> } } }]);
-
-<span class="hljs-built_in">console</span>.log(res);</code></pre>
-<p>In Mongoose 4.x, the above will print:</p>
-<pre><code>BulkWriteResult {
-  ok: [Getter],
-  nInserted: [Getter],
-  nUpserted: [Getter],
-  nMatched: [Getter],
-  nModified: [Getter],
-  nRemoved: [Getter],
-  getInsertedIds: [<span class="hljs-built_in">Function</span>],
-  getUpsertedIds: [<span class="hljs-built_in">Function</span>],
-  getUpsertedIdAt: [<span class="hljs-built_in">Function</span>],
-  getRawResponse: [<span class="hljs-built_in">Function</span>],
-  hasWriteErrors: [<span class="hljs-built_in">Function</span>],
-  getWriteErrorCount: [<span class="hljs-built_in">Function</span>],
-  getWriteErrorAt: [<span class="hljs-built_in">Function</span>],
-  getWriteErrors: [<span class="hljs-built_in">Function</span>],
-  getLastOp: [<span class="hljs-built_in">Function</span>],
-  getWriteConcernError: [<span class="hljs-built_in">Function</span>],
-  toJSON: [<span class="hljs-built_in">Function</span>],
-  toString: [<span class="hljs-built_in">Function</span>],
-  isOk: [<span class="hljs-built_in">Function</span>],
-  insertedCount: <span class="hljs-number">1</span>,
-  matchedCount: <span class="hljs-number">0</span>,
-  modifiedCount: <span class="hljs-number">0</span>,
-  deletedCount: <span class="hljs-number">0</span>,
-  upsertedCount: <span class="hljs-number">0</span>,
-  upsertedIds: {},
-  insertedIds: { <span class="hljs-string">'0'</span>: <span class="hljs-number">5</span>be9a3101638a066702a0d38 },
-  n: <span class="hljs-number">1</span> }</code></pre><p>In Mongoose 5.x, the script will print:</p>
-<pre><code>BulkWriteResult {
-  result: 
-  { ok: <span class="hljs-number">1</span>,
-    writeErrors: [],
-    writeConcernErrors: [],
-    insertedIds: [ [<span class="hljs-built_in">Object</span>] ],
-    nInserted: <span class="hljs-number">1</span>,
-    nUpserted: <span class="hljs-number">0</span>,
-    nMatched: <span class="hljs-number">0</span>,
-    nModified: <span class="hljs-number">0</span>,
-    nRemoved: <span class="hljs-number">0</span>,
-    upserted: [],
-    lastOp: { ts: [<span class="hljs-built_in">Object</span>], t: <span class="hljs-number">1</span> } },
-  insertedCount: <span class="hljs-number">1</span>,
-  matchedCount: <span class="hljs-number">0</span>,
-  modifiedCount: <span class="hljs-number">0</span>,
-  deletedCount: <span class="hljs-number">0</span>,
-  upsertedCount: <span class="hljs-number">0</span>,
-  upsertedIds: {},
-  insertedIds: { <span class="hljs-string">'0'</span>: <span class="hljs-number">5</span>be9a1c87decfc6443dd9f18 },
-  n: <span class="hljs-number">1</span> }</code></pre></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/migration.html b/docs/migration.html
deleted file mode 100644
index 5f4632abd3e..00000000000
--- a/docs/migration.html
+++ /dev/null
@@ -1,87 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Migration Guide</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><style>table td {
-  padding-right: 15px;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2>Migrating from 3.x to 4.x</h2><p>There are several <a href="https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes">backwards-breaking changes</a> to be aware of when migrating from Mongoose 3 to Mongoose 4.</p>
-<h3 id="findandmodify-new">`findOneAndUpdate()` new field is now `false` by default</h3>
-
-<p>Mongoose&#39;s <code>findOneAndUpdate()</code>, <code>findOneAndRemove()</code>,
-<code>findByIdAndUpdate()</code>, and <code>findByIdAndRemove()</code> functions are just
-wrappers around MongoDB&#39;s
-<a href="http://docs.mongodb.org/manual/reference/method/db.collection.findAndModify/"><code>findAndModify</code> command</a>.
-Both the MongoDB server and the MongoDB NodeJS driver set the <code>new</code> option
-to false by default, but mongoose 3 overwrote this default. In order to be
-more consistent with the MongoDB server&#39;s documentation, mongoose will
-use false by default. That is,
-<code>findOneAndUpdate({}, { $set: { test: 1 } }, callback);</code> will return the
-document as it was <em>before</em> the <code>$set</code> operation was applied.</p>
-<p>To return the document with modifications made on the update, use the <code>new: true</code> option.</p>
-<pre><code class="language-javascript">MyModel.findOneAndUpdate({}, { $set: { test: <span class="hljs-number">1</span> } }, { <span class="hljs-keyword">new</span>: <span class="hljs-literal">true</span> }, callback);</code></pre>
-<h3 id="casterror-and-validationerror-now-use-kind-instead-of-type-to-report-error-types">CastError and ValidationError now use <code>kind</code> instead of <code>type</code> to report error types</h3>
-<p>In Mongoose 3, CastError and ValidationError had a <code>type</code> field. For instance, user defined validation errors would have a <code>type</code> property that contained the string &#39;user defined&#39;. In Mongoose 4, this property has been renamed to <code>kind</code> due to <a href="https://code.google.com/p/v8/issues/detail?id=2397">the V8 JavaScript engine using the Error.type property internally</a>.</p>
-<h3 id="promises">Query now has a `.then()` function</h3>
-
-<p>In mongoose 3, you needed to call <code>.exec()</code> on a query chain to get a
-promise back, like <code>MyModel.find().exec().then();</code>. Mongoose 4 queries are
-promises, so you can do <code>MyModel.find().then()</code> instead. Be careful if
-you&#39;re using functions like
-<a href="https://github.com/kriskowal/q#adapting-node">q&#39;s <code>Q.ninvoke()</code></a> or
-otherwise returning a mongoose query from a promise.</p>
-<h3 id="moreinfo">More Info</h3>
-
-<p>Related blog posts:</p>
-<ul>
-<li><a href="http://www.mongodb.com/blog/post/introducing-version-40-mongoose-nodejs-odm">Introducing Version 4.0 of the Mongoose NodeJS ODM</a></li>
-</ul>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/models.html b/docs/models.html
deleted file mode 100644
index a5bdfad2d7c..00000000000
--- a/docs/models.html
+++ /dev/null
@@ -1,158 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Models</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="models">Models</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p><a href="./api.html#model-js">Models</a> are fancy constructors compiled from
-<code>Schema</code> definitions. An instance of a model is called a
-<a href="./documents.html">document</a>. Models are responsible for creating and
-reading documents from the underlying MongoDB database.</p>
-<ul><li><a href="#compiling">Compiling your first model</a></li><li><a href="#constructing-documents">Constructing Documents</a></li><li><a href="#querying">Querying</a></li><li><a href="#deleting">Deleting</a></li><li><a href="#updating">Updating</a></li><li><a href="#change-streams">Change Streams</a></li></ul><h3 id="compiling">Compiling your first model</h3><p>When you call <code>mongoose.model()</code> on a schema, Mongoose <em>compiles</em> a model
-for you.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-string">'string'</span>, size: <span class="hljs-string">'string'</span> });
-<span class="hljs-keyword">var</span> Tank = mongoose.model(<span class="hljs-string">'Tank'</span>, schema);</code></pre>
-<p>The first argument is the <em>singular</em> name of the collection your model is
-for. ** Mongoose automatically looks for the plural, lowercased version of your model name. **
-Thus, for the example above, the model Tank is for the <strong>tanks</strong> collection
-in the database.</p>
-<p><strong>Note:</strong> The <code>.model()</code> function makes a copy of <code>schema</code>. Make sure that
-you&#39;ve added everything you want to <code>schema</code>, including hooks,
-before calling <code>.model()</code>!</p>
-<h3 id="constructing-documents">Constructing Documents</h3><p>An instance of a model is called a <a href="./documents.html">document</a>. Creating
-them and saving to the database is easy.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Tank = mongoose.model(<span class="hljs-string">'Tank'</span>, yourSchema);
-
-<span class="hljs-keyword">var</span> small = <span class="hljs-keyword">new</span> Tank({ size: <span class="hljs-string">'small'</span> });
-small.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-comment">// saved!</span>
-});
-
-<span class="hljs-comment">// or</span>
-
-Tank.create({ size: <span class="hljs-string">'small'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, small</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-comment">// saved!</span>
-});
-
-<span class="hljs-comment">// or, for inserting large batches of documents</span>
-Tank.insertMany([{ size: <span class="hljs-string">'small'</span> }], <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-
-});</code></pre>
-<p>Note that no tanks will be created/removed until the connection your model
-uses is open. Every model has an associated connection. When you use
-<code>mongoose.model()</code>, your model will use the default mongoose connection.</p>
-<pre><code class="language-javascript">mongoose.connect(<span class="hljs-string">'mongodb://localhost/gettingstarted'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});</code></pre>
-<p>If you create a custom connection, use that connection&#39;s <code>model()</code> function
-instead.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> connection = mongoose.createConnection(<span class="hljs-string">'mongodb://localhost:27017/test'</span>);
-<span class="hljs-keyword">var</span> Tank = connection.model(<span class="hljs-string">'Tank'</span>, yourSchema);</code></pre>
-<h3 id="querying">Querying</h3><p>Finding documents is easy with Mongoose, which supports the <a href="http://www.mongodb.org/display/DOCS/Advanced+Queries">rich</a> query syntax of MongoDB. Documents can be retreived using each <code>models</code> <a href="./api.html#model_Model.find">find</a>, <a href="./api.html#model_Model.findById">findById</a>, <a href="./api.html#model_Model.findOne">findOne</a>, or <a href="./api.html#model_Model.where">where</a> static methods.</p>
-<pre><code class="language-javascript">Tank.find({ size: <span class="hljs-string">'small'</span> }).where(<span class="hljs-string">'createdDate'</span>).gt(oneYearAgo).exec(callback);</code></pre>
-<p>See the chapter on <a href="./queries.html">queries</a> for more details on how to use the <a href="./api.html#query-js">Query</a> api.</p>
-<h3 id="deleting">Deleting</h3><p>Models have static <code>deleteOne()</code> and <code>deleteMany()</code> functions
-for removing all documents matching the given <code>filter</code>.</p>
-<pre><code class="language-javascript">Tank.deleteOne({ size: <span class="hljs-string">'large'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-comment">// deleted at most one tank document</span>
-});</code></pre>
-<h3 id="updating">Updating</h3><p>Each <code>model</code> has its own <code>update</code> method for modifying documents in the
-database without returning them to your application. See the
-<a href="./api.html#model_Model.updateOne">API</a> docs for more detail.</p>
-<pre><code class="language-javascript">Tank.updateOne({ size: <span class="hljs-string">'large'</span> }, { name: <span class="hljs-string">'T-90'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err, res</span>) </span>{
-  <span class="hljs-comment">// Updated at most one doc, `res.modifiedCount` contains the number</span>
-  <span class="hljs-comment">// of docs that MongoDB updated</span>
-});</code></pre>
-<p><em>If you want to update a single document in the db and return it to your
-application, use <a href="./api.html#model_Model.findOneAndUpdate">findOneAndUpdate</a>
-instead.</em></p>
-<h3 id="change-streams">Change Streams</h3><p><em>New in MongoDB 3.6.0 and Mongoose 5.0.0</em></p>
-<p><a href="https://docs.mongodb.com/manual/changeStreams/">Change streams</a> provide
-a way for you to listen to all inserts and updates going through your
-MongoDB database. Note that change streams do <strong>not</strong> work unless you&#39;re
-connected to a <a href="https://docs.mongodb.com/manual/replication/">MongoDB replica set</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">async</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">run</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Create a new mongoose model</span>
-  <span class="hljs-keyword">const</span> personSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-    name: <span class="hljs-built_in">String</span>
-  });
-  <span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, personSchema, <span class="hljs-string">'Person'</span>);
-
-  <span class="hljs-comment">// Create a change stream. The 'change' event gets emitted when there's a</span>
-  <span class="hljs-comment">// change in the database</span>
-  Person.watch().
-    on(<span class="hljs-string">'change'</span>, data =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(), data));
-
-  <span class="hljs-comment">// Insert a doc, will trigger the change stream handler above</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(), <span class="hljs-string">'Inserting doc'</span>);
-  <span class="hljs-keyword">await</span> Person.create({ name: <span class="hljs-string">'Axl Rose'</span> });
-}</code></pre>
-<p>The output from the above <a href="http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html">async function</a> will look like what you see below.</p>
-<pre><code><span class="hljs-number">2018</span><span class="hljs-number">-05</span><span class="hljs-number">-11</span>T15:<span class="hljs-number">05</span>:<span class="hljs-number">35.467</span>Z <span class="hljs-string">'Inserting doc'</span>
-<span class="hljs-number">2018</span><span class="hljs-number">-05</span><span class="hljs-number">-11</span>T15:<span class="hljs-number">05</span>:<span class="hljs-number">35.487</span>Z <span class="hljs-string">'Inserted doc'</span>
-<span class="hljs-number">2018</span><span class="hljs-number">-05</span><span class="hljs-number">-11</span>T15:<span class="hljs-number">05</span>:<span class="hljs-number">35.491</span>Z { _id: { _data: ... },
-  operationType: <span class="hljs-string">'insert'</span>,
-  fullDocument: { _id: <span class="hljs-number">5</span>af5b13fe526027666c6bf83, name: <span class="hljs-string">'Axl Rose'</span>, __v: <span class="hljs-number">0</span> },
-  ns: { db: <span class="hljs-string">'test'</span>, coll: <span class="hljs-string">'Person'</span> },
-  documentKey: { _id: <span class="hljs-number">5</span>af5b13fe526027666c6bf83 } }</code></pre><p>You can read more about <a href="http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-change-streams.html#change-streams-in-mongoose">change streams in mongoose in this blog post</a>.</p>
-<h3>Yet more</h3><p>The <a href="./api.html#model_Model">API docs</a> cover many additional methods available like <a href="./api.html#model_Model.count">count</a>, <a href="./api.html#model_Model.mapReduce">mapReduce</a>, <a href="./api.html#model_Model.aggregate">aggregate</a>, and <a href="./api.html#model_Model.findOneAndRemove">more</a>.</p>
-<h3 id="next">Next Up</h3><p>Now that we&#39;ve covered <code>Models</code>, let&#39;s take a look at <a href="/docs/documents.html">Documents</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/plugins.html b/docs/plugins.html
deleted file mode 100644
index 3d8d6b24eb5..00000000000
--- a/docs/plugins.html
+++ /dev/null
@@ -1,124 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Plugins</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="plugins">Plugins</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Schemas are pluggable, that is, they allow for applying pre-packaged capabilities to extend their functionality. This is a very powerful feature.</p>
-<ul class="toc">
-  <li><a href="#example">Example</a></li>
-  <li><a href="#global">Global Plugins</a></li>
-  <li><a href="#official">Officially Supported Plugins</a></li>
-</ul>
-
-<h3 id="example">Example</h3>
-<p>Suppose that we have several collections in our database and want to add last-modified functionality to each one. With plugins this is easy. Just create a plugin once and apply it to each <code>Schema</code>:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// lastMod.js</span>
-<span class="hljs-built_in">module</span>.exports = exports = <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">lastModifiedPlugin</span> (<span class="hljs-params">schema, options</span>) </span>{
-  schema.add({ lastMod: <span class="hljs-built_in">Date</span> });
-
-  schema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">next</span>) </span>{
-    <span class="hljs-keyword">this</span>.lastMod = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>();
-    next();
-  });
-
-  <span class="hljs-keyword">if</span> (options &amp;&amp; options.index) {
-    schema.path(<span class="hljs-string">'lastMod'</span>).index(options.index);
-  }
-}
-
-<span class="hljs-comment">// game-schema.js</span>
-<span class="hljs-keyword">var</span> lastMod = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./lastMod'</span>);
-<span class="hljs-keyword">var</span> Game = <span class="hljs-keyword">new</span> Schema({ ... });
-Game.plugin(lastMod, { index: <span class="hljs-literal">true</span> });
-
-<span class="hljs-comment">// player-schema.js</span>
-<span class="hljs-keyword">var</span> lastMod = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./lastMod'</span>);
-<span class="hljs-keyword">var</span> Player = <span class="hljs-keyword">new</span> Schema({ ... });
-Player.plugin(lastMod);</code></pre>
-<p>We just added last-modified behavior to both our <code>Game</code> and <code>Player</code> schemas and declared an index on the <code>lastMod</code> path of our Games to boot. Not bad for a few lines of code.</p>
-<h3 id="global"><a href="#global">Global Plugins</a></h3>
-
-<p>Want to register a plugin for all schemas? The mongoose singleton has a
-<code>.plugin()</code> function that registers a plugin for every schema. For
-example:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.plugin(<span class="hljs-built_in">require</span>(<span class="hljs-string">'./lastMod'</span>));
-
-<span class="hljs-keyword">var</span> gameSchema = <span class="hljs-keyword">new</span> Schema({ ... });
-<span class="hljs-keyword">var</span> playerSchema = <span class="hljs-keyword">new</span> Schema({ ... });
-<span class="hljs-comment">// `lastModifiedPlugin` gets attached to both schemas</span>
-<span class="hljs-keyword">var</span> Game = mongoose.model(<span class="hljs-string">'Game'</span>, gameSchema);
-<span class="hljs-keyword">var</span> Player = mongoose.model(<span class="hljs-string">'Player'</span>, playerSchema);</code></pre>
-<h3 id="official"><a href="#official">Officially Supported Plugins</a></h3>
-
-<p>The Mongoose team maintains several plugins that add cool new features to
-Mongoose. Here&#39;s a few:</p>
-<ul>
-<li><a href="http://plugins.mongoosejs.io/plugins/autopopulate">mongoose-autopopulate</a>: Always <a href="/docs/populate.html"><code>populate()</code></a> certain fields in your Mongoose schemas.</li>
-<li><a href="http://plugins.mongoosejs.io/plugins/lean-virtuals">mongoose-lean-virtuals</a>: Attach virtuals to the results of Mongoose queries when using <a href="/docs/api.html#query_Query-lean"><code>.lean()</code></a>.</li>
-</ul>
-<h3 id="community">Community!</h3>
-<p>Not only can you re-use schema functionality in your own projects, but you
-also reap the benefits of the Mongoose community as well. Any plugin
-published to <a href="https://npmjs.org/">npm</a> and
-<a href="https://npmjs.org/doc/tag.html">tagged</a> with <code>mongoose</code> will show up on
-our <a href="http://plugins.mongoosejs.io">search results</a> page.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/populate.html b/docs/populate.html
deleted file mode 100644
index 3ecf047fe72..00000000000
--- a/docs/populate.html
+++ /dev/null
@@ -1,521 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Query Population</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="populate">Populate</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>MongoDB has the join-like <a href="https://docs.mongodb.com/manual/reference/operator/aggregation/lookup/">$lookup</a> aggregation operator in versions &gt;= 3.2. Mongoose has a more powerful alternative called <code>populate()</code>, which lets you reference documents in other collections.</p>
-<p>Population is the process of automatically replacing the specified paths in the document with document(s) from other collection(s). We may populate a single document, multiple documents, plain object, multiple plain objects, or all objects returned from a query. Let&#39;s look at some examples.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">const</span> Schema = mongoose.Schema;
-
-<span class="hljs-keyword">const</span> personSchema = Schema({
-  _id: Schema.Types.ObjectId,
-  name: <span class="hljs-built_in">String</span>,
-  age: <span class="hljs-built_in">Number</span>,
-  stories: [{ type: Schema.Types.ObjectId, ref: <span class="hljs-string">'Story'</span> }]
-});
-
-<span class="hljs-keyword">const</span> storySchema = Schema({
-  author: { type: Schema.Types.ObjectId, ref: <span class="hljs-string">'Person'</span> },
-  title: <span class="hljs-built_in">String</span>,
-  fans: [{ type: Schema.Types.ObjectId, ref: <span class="hljs-string">'Person'</span> }]
-});
-
-<span class="hljs-keyword">const</span> Story = mongoose.model(<span class="hljs-string">'Story'</span>, storySchema);
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, personSchema);</code></pre>
-<p>So far we&#39;ve created two <a href="./models.html">Models</a>. Our <code>Person</code> model has
-its <code>stories</code> field set to an array of <code>ObjectId</code>s. The <code>ref</code> option is
-what tells Mongoose which model to use during population, in our case
-the <code>Story</code> model. All <code>_id</code>s we store here must be document <code>_id</code>s from
-the <code>Story</code> model.</p>
-<p><strong>Note</strong>: <code>ObjectId</code>, <code>Number</code>, <code>String</code>, and <code>Buffer</code> are valid for use
-as refs. However, you should use <code>ObjectId</code> unless you are an advanced
-user and have a good reason for doing so.</p>
-<ul class="toc">
-  <li><a href="#saving-refs">Saving Refs</a></li>
-  <li><a href="#population">Population</a></li>
-  <li><a href="#setting-populated-fields">Setting Populated Fields</a></li>
-  <li><a href="#doc-not-found">What If There's No Foreign Document?</a></li>
-  <li><a href="#field-selection">Field Selection</a></li>
-  <li><a href="#populating-multiple-paths">Populating Multiple Paths</a></li>
-  <li><a href="#query-conditions">Query conditions and other options</a></li>
-  <li><a href="#refs-to-children">Refs to children</a></li>
-  <li><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></li>
-  <li><a href="#populate_multiple_documents">Populating multiple existing documents</a></li>
-  <li><a href="#deep-populate">Populating across multiple levels</a></li>
-  <li><a href="#cross-db-populate">Populating across Databases</a></li>
-  <li><a href="#dynamic-ref">Dynamic References via `refPath`</a></li>
-  <li><a href="#populate-virtuals">Populate Virtuals</a></li>
-  <li><a href="#count">Populate Virtuals: The Count Option</a></li>
-  <li><a href="#populate-middleware">Populate in Middleware</a></li>
-</ul>
-
-<h3 id="saving-refs"><a href="#saving-refs">Saving refs</a></h3>
-
-<p>Saving refs to other documents works the same way you normally save
-properties, just assign the <code>_id</code> value:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> author = <span class="hljs-keyword">new</span> Person({
-  _id: <span class="hljs-keyword">new</span> mongoose.Types.ObjectId(),
-  name: <span class="hljs-string">'Ian Fleming'</span>,
-  age: <span class="hljs-number">50</span>
-});
-
-author.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-
-  <span class="hljs-keyword">const</span> story1 = <span class="hljs-keyword">new</span> Story({
-    title: <span class="hljs-string">'Casino Royale'</span>,
-    author: author._id    <span class="hljs-comment">// assign the _id from the person</span>
-  });
-
-  story1.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-    <span class="hljs-comment">// thats it!</span>
-  });
-});</code></pre>
-<h3 id="population"><a href="#population">Population</a></h3>
-
-<p>So far we haven&#39;t done anything much different. We&#39;ve merely created a
-<code>Person</code> and a <code>Story</code>. Now let&#39;s take a look at populating our story&#39;s
-<code>author</code> using the query builder:</p>
-<pre><code class="language-javascript">Story.
-  findOne({ title: <span class="hljs-string">'Casino Royale'</span> }).
-  populate(<span class="hljs-string">'author'</span>).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, story</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'The author is %s'</span>, story.author.name);
-    <span class="hljs-comment">// prints "The author is Ian Fleming"</span>
-  });</code></pre>
-<p>Populated paths are no longer set to their original <code>_id</code> , their value
-is replaced with the mongoose document returned from the database by
-performing a separate query before returning the results.</p>
-<p>Arrays of refs work the same way. Just call the
-<a href="./api.html#query_Query-populate">populate</a> method on the query and an
-array of documents will be returned <em>in place</em> of the original <code>_id</code>s.</p>
-<h3 id="setting-populated-fields"><a href="#setting-populated-fields">Setting Populated Fields</a></h3>
-
-<p>You can manually populate a property by setting it to a document. The document
-must be an instance of the model your <code>ref</code> property refers to.</p>
-<pre><code class="language-javascript">Story.findOne({ title: <span class="hljs-string">'Casino Royale'</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, story</span>) </span>{
-  <span class="hljs-keyword">if</span> (error) {
-    <span class="hljs-keyword">return</span> handleError(error);
-  }
-  story.author = author;
-  <span class="hljs-built_in">console</span>.log(story.author.name); <span class="hljs-comment">// prints "Ian Fleming"</span>
-});</code></pre>
-<h3 id="doc-not-found"><a href="#doc-not-found">What If There's No Foreign Document?</a></h3>
-
-<p>Mongoose populate doesn&#39;t behave like conventional
-<a href="https://www.w3schools.com/sql/sql_join.asp">SQL joins</a>. When there&#39;s no
-document, <code>story.author</code> will be <code>null</code>. This is analogous to a
-<a href="https://www.w3schools.com/sql/sql_join_left.asp">left join</a> in SQL.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">await</span> Person.deleteMany({ name: <span class="hljs-string">'Ian Fleming'</span> });
-
-<span class="hljs-keyword">const</span> story = <span class="hljs-keyword">await</span> Story.findOne({ title: <span class="hljs-string">'Casino Royale'</span> }).populate(<span class="hljs-string">'author'</span>);
-story.author; <span class="hljs-comment">// `null`</span></code></pre>
-<p>If you have an array of <code>authors</code> in your <code>storySchema</code>, <code>populate()</code> will
-give you an empty array instead.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> storySchema = Schema({
-  authors: [{ type: Schema.Types.ObjectId, ref: <span class="hljs-string">'Person'</span> }],
-  title: <span class="hljs-built_in">String</span>
-});
-
-<span class="hljs-comment">// Later</span>
-
-<span class="hljs-keyword">const</span> story = <span class="hljs-keyword">await</span> Story.findOne({ title: <span class="hljs-string">'Casino Royale'</span> }).populate(<span class="hljs-string">'authors'</span>);
-story.authors; <span class="hljs-comment">// `[]`</span></code></pre>
-<h3 id="field-selection"><a href="#field-selection">Field Selection</a></h3>
-
-<p>What if we only want a few specific fields returned for the populated
-documents? This can be accomplished by passing the usual
-<a href="./api.html#query_Query-select">field name syntax</a> as the second argument
-to the populate method:</p>
-<pre><code class="language-javascript">Story.
-  findOne({ title: <span class="hljs-regexp">/casino royale/i</span> }).
-  populate(<span class="hljs-string">'author'</span>, <span class="hljs-string">'name'</span>). <span class="hljs-comment">// only return the Persons name</span>
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, story</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'The author is %s'</span>, story.author.name);
-    <span class="hljs-comment">// prints "The author is Ian Fleming"</span>
-
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'The authors age is %s'</span>, story.author.age);
-    <span class="hljs-comment">// prints "The authors age is null'</span>
-  });</code></pre>
-<h3 id="populating-multiple-paths"><a href="#populating-multiple-paths">Populating Multiple Paths</a></h3>
-
-<p>What if we wanted to populate multiple paths at the same time?</p>
-<pre><code class="language-javascript">Story.
-  find(...).
-  populate(<span class="hljs-string">'fans'</span>).
-  populate(<span class="hljs-string">'author'</span>).
-  exec();</code></pre>
-<p>If you call <code>populate()</code> multiple times with the same path, only the last
-one will take effect.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// The 2nd `populate()` call below overwrites the first because they</span>
-<span class="hljs-comment">// both populate 'fans'.</span>
-Story.
-  find().
-  populate({ path: <span class="hljs-string">'fans'</span>, select: <span class="hljs-string">'name'</span> }).
-  populate({ path: <span class="hljs-string">'fans'</span>, select: <span class="hljs-string">'email'</span> });
-<span class="hljs-comment">// The above is equivalent to:</span>
-Story.find().populate({ path: <span class="hljs-string">'fans'</span>, select: <span class="hljs-string">'email'</span> });</code></pre>
-<h3 id="query-conditions"><a href="#query-conditions">Query conditions and other options</a></h3>
-
-<p>What if we wanted to populate our fans array based on their age, select
-just their names, and return at most, any 5 of them?</p>
-<pre><code class="language-javascript">Story.
-  find(...).
-  populate({
-    path: <span class="hljs-string">'fans'</span>,
-    match: { age: { $gte: <span class="hljs-number">21</span> }},
-    <span class="hljs-comment">// Explicitly exclude `_id`, see http://bit.ly/2aEfTdB</span>
-    select: <span class="hljs-string">'name -_id'</span>,
-    options: { limit: <span class="hljs-number">5</span> }
-  }).
-  exec();</code></pre>
-<h3 id="refs-to-children"><a href="#refs-to-children">Refs to children</a></h3>
-
-<p>We may find however, if we use the <code>author</code> object, we are unable to get a
-list of the stories. This is because no <code>story</code> objects were ever &#39;pushed&#39;
-onto <code>author.stories</code>.</p>
-<p>There are two perspectives here. First, you may want the <code>author</code> know
-which stories are theirs. Usually, your schema should resolve
-one-to-many relationships by having a parent pointer in the &#39;many&#39; side.
-But, if you have a good reason to want an array of child pointers, you
-can <code>push()</code> documents onto the array as shown below.</p>
-<pre><code class="language-javascript">author.stories.push(story1);
-author.save(callback);</code></pre>
-<p>This allows us to perform a <code>find</code> and <code>populate</code> combo:</p>
-<pre><code class="language-javascript">Person.
-  findOne({ name: <span class="hljs-string">'Ian Fleming'</span> }).
-  populate(<span class="hljs-string">'stories'</span>). <span class="hljs-comment">// only works if we pushed refs to children</span>
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, person</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-    <span class="hljs-built_in">console</span>.log(person);
-  });</code></pre>
-<p>It is debatable that we really want two sets of pointers as they may get
-out of sync. Instead we could skip populating and directly <code>find()</code> the
-stories we are interested in.</p>
-<pre><code class="language-javascript">Story.
-  find({ author: author._id }).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, stories</span>) </span>{
-    <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-    <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'The stories are an array: '</span>, stories);
-  });</code></pre>
-<p>The documents returned from
-<a href="./api.html#query_Query-populate">query population</a> become fully
-functional, <code>remove</code>able, <code>save</code>able documents unless the
-<a href="./api.html#query_Query-lean">lean</a> option is specified. Do not confuse
-them with <a href="./subdocs.html">sub docs</a>. Take caution when calling its
-remove method because you&#39;ll be removing it from the database, not just
-the array.</p>
-<h3 id="populate_an_existing_mongoose_document"><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></h3>
-
-<p>If we have an existing mongoose document and want to populate some of its
-paths, <strong>mongoose &gt;= 3.6</strong> supports the
-<a href="./api.html#document_Document-populate">document#populate()</a> method.</p>
-<h3 id="populate_multiple_documents"><a href="#populate_multiple_documents">Populating multiple existing documents</a></h3>
-
-<p>If we have one or many mongoose documents or even plain objects
-(<em>like <a href="./api.html#model_Model.mapReduce">mapReduce</a> output</em>), we may
-populate them using the <a href="./api.html#model_Model.populate">Model.populate()</a>
-method available in <strong>mongoose &gt;= 3.6</strong>. This is what <code>document#populate()</code>
-and <code>query#populate()</code> use to populate documents.</p>
-<h3 id="deep-populate"><a href="#deep-populate">Populating across multiple levels</a></h3>
-
-<p>Say you have a user schema which keeps track of the user&#39;s friends.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  friends: [{ type: ObjectId, ref: <span class="hljs-string">'User'</span> }]
-});</code></pre>
-<p>Populate lets you get a list of a user&#39;s friends, but what if you also
-wanted a user&#39;s friends of friends? Specify the <code>populate</code> option to tell
-mongoose to populate the <code>friends</code> array of all the user&#39;s friends:</p>
-<pre><code class="language-javascript">User.
-  findOne({ name: <span class="hljs-string">'Val'</span> }).
-  populate({
-    path: <span class="hljs-string">'friends'</span>,
-    <span class="hljs-comment">// Get friends of friends - populate the 'friends' array for every friend</span>
-    populate: { path: <span class="hljs-string">'friends'</span> }
-  });</code></pre>
-<h3 id="cross-db-populate"><a href="#cross-db-populate">Populating across Databases</a></h3>
-
-<p>Let&#39;s say you have a schema representing events, and a schema representing
-conversations. Each event has a corresponding conversation thread.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> eventSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  <span class="hljs-comment">// The id of the corresponding conversation</span>
-  <span class="hljs-comment">// Notice there's no ref here!</span>
-  conversation: ObjectId
-});
-<span class="hljs-keyword">var</span> conversationSchema = <span class="hljs-keyword">new</span> Schema({
-  numMessages: <span class="hljs-built_in">Number</span>
-});</code></pre>
-<p>Also, suppose that events and conversations are stored in separate MongoDB
-instances.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> db1 = mongoose.createConnection(<span class="hljs-string">'localhost:27000/db1'</span>);
-<span class="hljs-keyword">var</span> db2 = mongoose.createConnection(<span class="hljs-string">'localhost:27001/db2'</span>);
-
-<span class="hljs-keyword">var</span> Event = db1.model(<span class="hljs-string">'Event'</span>, eventSchema);
-<span class="hljs-keyword">var</span> Conversation = db2.model(<span class="hljs-string">'Conversation'</span>, conversationSchema);</code></pre>
-<p>In this situation, you will <strong>not</strong> be able to <code>populate()</code> normally.
-The <code>conversation</code> field will always be null, because <code>populate()</code> doesn&#39;t
-know which model to use. However,
-<a href="./api.html#model_Model.populate">you can specify the model explicitly</a>.</p>
-<pre><code class="language-javascript">Event.
-  find().
-  populate({ path: <span class="hljs-string">'conversation'</span>, model: Conversation }).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, docs</span>) </span>{ <span class="hljs-comment">/* ... */</span> });</code></pre>
-<p>This is known as a &quot;cross-database populate,&quot; because it enables you to
-populate across MongoDB databases and even across MongoDB instances.</p>
-<h3 id="dynamic-ref"><a href="#dynamic-ref">Dynamic References via `refPath`</a></h3>
-
-<p>Mongoose can also populate from multiple collections based on the value
-of a property in the document. Let&#39;s say you&#39;re building a schema for
-storing comments. A user may comment on either a blog post or a product.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> commentSchema = <span class="hljs-keyword">new</span> Schema({
-  body: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  on: {
-    type: Schema.Types.ObjectId,
-    required: <span class="hljs-literal">true</span>,
-    <span class="hljs-comment">// Instead of a hardcoded model name in `ref`, `refPath` means Mongoose</span>
-    <span class="hljs-comment">// will look at the `onModel` property to find the right model.</span>
-    refPath: <span class="hljs-string">'onModel'</span>
-  },
-  onModel: {
-    type: <span class="hljs-built_in">String</span>,
-    required: <span class="hljs-literal">true</span>,
-    enum: [<span class="hljs-string">'BlogPost'</span>, <span class="hljs-string">'Product'</span>]
-  }
-});
-
-<span class="hljs-keyword">const</span> Product = mongoose.model(<span class="hljs-string">'Product'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-<span class="hljs-keyword">const</span> BlogPost = mongoose.model(<span class="hljs-string">'BlogPost'</span>, <span class="hljs-keyword">new</span> Schema({ title: <span class="hljs-built_in">String</span> }));
-<span class="hljs-keyword">const</span> Comment = mongoose.model(<span class="hljs-string">'Comment'</span>, commentSchema);</code></pre>
-<p>The <code>refPath</code> option is a more sophisticated alternative to <code>ref</code>. If <code>ref</code>
-is just a string, Mongoose will always query the same model to find the
-populated subdocs. With <code>refPath</code>, you can configure what model Mongoose
-uses for each document.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> book = <span class="hljs-keyword">await</span> Product.create({ name: <span class="hljs-string">'The Count of Monte Cristo'</span> });
-<span class="hljs-keyword">const</span> post = <span class="hljs-keyword">await</span> BlogPost.create({ title: <span class="hljs-string">'Top 10 French Novels'</span> });
-
-<span class="hljs-keyword">const</span> commentOnBook = <span class="hljs-keyword">await</span> Comment.create({
-  body: <span class="hljs-string">'Great read'</span>,
-  on: book._id,
-  onModel: <span class="hljs-string">'Product'</span>
-});
-
-<span class="hljs-keyword">const</span> commentOnPost = <span class="hljs-keyword">await</span> Comment.create({
-  body: <span class="hljs-string">'Very informative'</span>,
-  on: post._id,
-  onModel: <span class="hljs-string">'BlogPost'</span>
-});
-
-<span class="hljs-comment">// The below `populate()` works even though one comment references the</span>
-<span class="hljs-comment">// 'Product' collection and the other references the 'BlogPost' collection.</span>
-<span class="hljs-keyword">const</span> comments = <span class="hljs-keyword">await</span> Comment.find().populate(<span class="hljs-string">'on'</span>).sort({ body: <span class="hljs-number">1</span> });
-comments[<span class="hljs-number">0</span>].on.name; <span class="hljs-comment">// "The Count of Monte Cristo"</span>
-comments[<span class="hljs-number">1</span>].on.title; <span class="hljs-comment">// "Top 10 French Novels"</span></code></pre>
-<p>An alternative approach is to define separate <code>blogPost</code> and
-<code>product</code> properties on <code>commentSchema</code>, and then <code>populate()</code> on both
-properties.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> commentSchema = <span class="hljs-keyword">new</span> Schema({
-  body: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  product: {
-    type: Schema.Types.ObjectId,
-    required: <span class="hljs-literal">true</span>,
-    ref: <span class="hljs-string">'Product'</span>
-  },
-  blogPost: {
-    type: Schema.Types.ObjectId,
-    required: <span class="hljs-literal">true</span>,
-    ref: <span class="hljs-string">'BlogPost'</span>
-  }
-});
-
-<span class="hljs-comment">// ...</span>
-
-<span class="hljs-comment">// The below `populate()` is equivalent to the `refPath` approach, you</span>
-<span class="hljs-comment">// just need to make sure you `populate()` both `product` and `blogPost`.</span>
-<span class="hljs-keyword">const</span> comments = <span class="hljs-keyword">await</span> Comment.find().
-  populate(<span class="hljs-string">'product'</span>).
-  populate(<span class="hljs-string">'blogPost'</span>).
-  sort({ body: <span class="hljs-number">1</span> });
-comments[<span class="hljs-number">0</span>].product.name; <span class="hljs-comment">// "The Count of Monte Cristo"</span>
-comments[<span class="hljs-number">1</span>].blogPost.title; <span class="hljs-comment">// "Top 10 French Novels"</span></code></pre>
-<p>Defining separate <code>blogPost</code> and <code>product</code> properties works for this simple
-example. But, if you decide to allow users to also comment on articles or
-other comments, you&#39;ll need to add more properties to your schema. You&#39;ll
-also need an extra <code>populate()</code> call for every property, unless you use
-<a href="https://www.npmjs.com/package/mongoose-autopopulate">mongoose-autopopulate</a>.
-Using <code>refPath</code> means you only need 2 schema paths and one <code>populate()</code> call
-regardless of how many models your <code>commentSchema</code> can point to.</p>
-<h3 id="populate-virtuals"><a href="#populate-virtuals">Populate Virtuals</a></h3>
-
-<p>So far you&#39;ve only populated based on the <code>_id</code> field. However, that&#39;s
-sometimes not the right choice.
-In particular, <a href="https://docs.mongodb.com/manual/tutorial/model-referenced-one-to-many-relationships-between-documents/">arrays that grow without bound are a MongoDB anti-pattern</a>.
-Using mongoose virtuals, you can define more sophisticated relationships
-between documents.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> PersonSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  band: <span class="hljs-built_in">String</span>
-});
-
-<span class="hljs-keyword">const</span> BandSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>
-});
-BandSchema.virtual(<span class="hljs-string">'members'</span>, {
-  ref: <span class="hljs-string">'Person'</span>, <span class="hljs-comment">// The model to use</span>
-  localField: <span class="hljs-string">'name'</span>, <span class="hljs-comment">// Find people where `localField`</span>
-  foreignField: <span class="hljs-string">'band'</span>, <span class="hljs-comment">// is equal to `foreignField`</span>
-  <span class="hljs-comment">// If `justOne` is true, 'members' will be a single doc as opposed to</span>
-  <span class="hljs-comment">// an array. `justOne` is false by default.</span>
-  justOne: <span class="hljs-literal">false</span>,
-  options: { sort: { name: <span class="hljs-number">-1</span> }, limit: <span class="hljs-number">5</span> } <span class="hljs-comment">// Query options, see http://bit.ly/mongoose-query-options</span>
-});
-
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, PersonSchema);
-<span class="hljs-keyword">const</span> Band = mongoose.model(<span class="hljs-string">'Band'</span>, BandSchema);
-
-<span class="hljs-comment">/**
- * Suppose you have 2 bands: "Guns N' Roses" and "Motley Crue"
- * And 4 people: "Axl Rose" and "Slash" with "Guns N' Roses", and
- * "Vince Neil" and "Nikki Sixx" with "Motley Crue"
- */</span>
-Band.find({}).populate(<span class="hljs-string">'members'</span>).exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, bands</span>) </span>{
-  <span class="hljs-comment">/* `bands.members` is now an array of instances of `Person` */</span>
-});</code></pre>
-<p>Keep in mind that virtuals are <em>not</em> included in <code>toJSON()</code> output by default. If you want populate virtuals to show up when using functions
-that rely on <code>JSON.stringify()</code>, like Express&#39;
-<a href="http://expressjs.com/en/4x/api.html#res.json"><code>res.json()</code> function</a>,
-set the <code>virtuals: true</code> option on your schema&#39;s <code>toJSON</code> options.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Set `virtuals: true` so `res.json()` works</span>
-<span class="hljs-keyword">const</span> BandSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>
-}, { toJSON: { virtuals: <span class="hljs-literal">true</span> } });</code></pre>
-<p>If you&#39;re using populate projections, make sure <code>foreignField</code> is included
-in the projection.</p>
-<pre><code class="language-javascript">Band.
-  find({}).
-  populate({ path: <span class="hljs-string">'members'</span>, select: <span class="hljs-string">'name'</span> }).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, bands</span>) </span>{
-    <span class="hljs-comment">// Won't work, foreign field `band` is not selected in the projection</span>
-  });
-
-Band.
-  find({}).
-  populate({ path: <span class="hljs-string">'members'</span>, select: <span class="hljs-string">'name band'</span> }).
-  exec(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error, bands</span>) </span>{
-    <span class="hljs-comment">// Works, foreign field `band` is selected</span>
-  });</code></pre>
-<h3 id="count"><a href="#count">Populate Virtuals: The Count Option</a></h3>
-
-<p>Populate virtuals also support counting the number of documents with
-matching <code>foreignField</code> as opposed to the documents themselves. Set the
-<code>count</code> option on your virtual:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> PersonSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  band: <span class="hljs-built_in">String</span>
-});
-
-<span class="hljs-keyword">const</span> BandSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>
-});
-BandSchema.virtual(<span class="hljs-string">'numMembers'</span>, {
-  ref: <span class="hljs-string">'Person'</span>, <span class="hljs-comment">// The model to use</span>
-  localField: <span class="hljs-string">'name'</span>, <span class="hljs-comment">// Find people where `localField`</span>
-  foreignField: <span class="hljs-string">'band'</span>, <span class="hljs-comment">// is equal to `foreignField`</span>
-  count: <span class="hljs-literal">true</span> <span class="hljs-comment">// And only get the number of docs</span>
-});
-
-<span class="hljs-comment">// Later</span>
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> Band.findOne({ name: <span class="hljs-string">'Motley Crue'</span> }).
-  populate(<span class="hljs-string">'numMembers'</span>);
-doc.numMembers; <span class="hljs-comment">// 2</span></code></pre>
-<h3 id="populate-middleware"><a href="#populate-middleware">Populate in Middleware</a></h3>
-
-<p>You can populate in either pre or post <a href="http://mongoosejs.com/docs/middleware.html">hooks</a>. If you want to
-always populate a certain field, check out the <a href="http://npmjs.com/package/mongoose-autopopulate">mongoose-autopopulate plugin</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Always attach `populate()` to `find()` calls</span>
-MySchema.pre(<span class="hljs-string">'find'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">this</span>.populate(<span class="hljs-string">'user'</span>);
-});</code></pre>
-<pre><code class="language-javascript"><span class="hljs-comment">// Always `populate()` after `find()` calls. Useful if you want to selectively populate</span>
-<span class="hljs-comment">// based on the docs found.</span>
-MySchema.post(<span class="hljs-string">'find'</span>, <span class="hljs-keyword">async</span> <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">docs</span>) </span>{
-  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> doc <span class="hljs-keyword">of</span> docs) {
-    <span class="hljs-keyword">if</span> (doc.isPublic) {
-      <span class="hljs-keyword">await</span> doc.populate(<span class="hljs-string">'user'</span>).execPopulate();
-    }
-  }
-});</code></pre>
-<pre><code class="language-javascript"><span class="hljs-comment">// `populate()` after saving. Useful for sending populated data back to the client in an</span>
-<span class="hljs-comment">// update API endpoint</span>
-MySchema.post(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc, next</span>) </span>{
-  doc.populate(<span class="hljs-string">'user'</span>).execPopulate().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-    next();
-  });
-});</code></pre>
-<h3 id="next-up">Next Up</h3>
-<p>Now that we&#39;ve covered <code>populate()</code>, let&#39;s take a look at <a href="/docs/discriminators.html">discriminators</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/prior.html b/docs/prior.html
deleted file mode 100644
index cf7f3f49101..00000000000
--- a/docs/prior.html
+++ /dev/null
@@ -1,53 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: </title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2>Prior Release Documentation</h2><ul><li><a href="/docs/3.8.x/">3.8.x</a></li><li><a href="/docs/3.7.x/">3.7.x</a></li><li><a href="/docs/3.6.x/">3.6.x</a></li><li><a href="/docs/3.5.x/">3.5.x</a></li><li><a href="/docs/3.4.x/">3.4.x</a></li><li><a href="/docs/3.3.x/">3.3.x</a></li><li><a href="/docs/3.2.x/">3.2.x</a></li><li><a href="/docs/3.1.x/">3.1.x</a></li><li><a href="/docs/3.0.x/">3.0.x</a></li><li><a href="/docs/2.8.x/">2.8.x</a></li><li><a href="/docs/2.7.x/">2.7.x</a></li></ul></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/production.html b/docs/production.html
deleted file mode 100644
index 35b9eb10481..00000000000
--- a/docs/production.html
+++ /dev/null
@@ -1,9 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><meta http-equiv="refresh" content="5;url=http://mongoosejs.tumblr.com/"><link href="//fonts.googleapis.com/css?family=Anonymous+Pro:400,700|Droid+Sans+Mono|Open+Sans:400,700|Linden+Hill|Quattrocento:400,700|News+Cycle:400,700|Antic+Slab|Cabin+Condensed:400,700" rel="stylesheet" type="text/css"><link href="/docs/css/default.css" rel="stylesheet" type="text/css"><link href="/docs/css/guide.css" rel="stylesheet" type="text/css"></head><body><a id="forkbanner" href="http://github.com/Automattic/mongoose"><img style="position: absolute; top: 0; right: 0; border: 0;" src="https://s3.amazonaws.com/github/ribbons/forkme_right_gray_6d6d6d.png" alt="Fork me on GitHub"></a><div id="links"><div id="header"><h1><a href="../index.html"><div class="mongoose">Mongoose</div></a></h1></div><ul><li class="home"><a href="../index.html">home</a></li><li class="faq"><a href="./faq.html">FAQ</a></li><li class="plugins"><a href="http://plugins.mongoosejs.io">plugins</a></li><li class="changelog"><a href="http://github.com/Automattic/mongoose/tree/master/History.md">change log</a></li><li class="support"><a href="../index.html#support">support</a></li><li class="fork"><a href="http://github.com/Automattic/mongoose">fork</a></li><li class="guide"><a href="./guide.html">guide</a></li><li class="api"><a href="./api.html">API docs</a></li><li class="quickstart"><a href="./index.html">quick start</a></li><li class="contrib"><a href="http://github.com/Automattic/mongoose/contributors">contributors</a></li><li class="prior"><a href="./prior.html">prior releases</a></li></ul></div><div id="content"><div class="module"><p>You are being redirected to http://mongoosejs.tumblr.com.<br>Please <a href="http://mongoosejs.tumblr.com/">click here</a> if you are not redirected in 5 seconds.</p></div></div><script>document.body.className = 'load';</script><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script></body></html>
\ No newline at end of file
diff --git a/docs/promises.html b/docs/promises.html
deleted file mode 100644
index 02356e12498..00000000000
--- a/docs/promises.html
+++ /dev/null
@@ -1,120 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Promises</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><ul class="toc"><li><a href="##{block.identifier}">Built-in Promises</a></li><li><a href="##{block.identifier}">Queries are not promises</a></li><li><a href="##{block.identifier}">Plugging in your own Promises Library</a></li></ul><h2 id="#{block.identifier}"><a href="##{block.identifier}">Built-in Promises</a></h2><p>Mongoose async operations, like <code>.save()</code> and queries, return thenables.
-This means that you can do things like <code>MyModel.findOne({}).then()</code> and
-<code>await MyModel.findOne({}).exec()</code> if you&#39;re using
-<a href="http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html">async/await</a>.</p>
-<p>You can find the return type of specific operations <a href="https://mongoosejs.com/docs/api.html">in the api docs</a></p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> gnr = <span class="hljs-keyword">new</span> Band({
-  name: <span class="hljs-string">"Guns N' Roses"</span>,
-  members: [<span class="hljs-string">'Axl'</span>, <span class="hljs-string">'Slash'</span>]
-});
-
-<span class="hljs-keyword">var</span> promise = gnr.save();
-assert.ok(promise <span class="hljs-keyword">instanceof</span> <span class="hljs-built_in">Promise</span>);
-
-promise.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-  assert.equal(doc.name, <span class="hljs-string">"Guns N' Roses"</span>);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Queries are not promises</a></h2><p><a href="http://mongoosejs.com/docs/queries.html">Mongoose queries</a> are <strong>not</strong> promises. They have a <code>.then()</code>
-function for <a href="https://www.npmjs.com/package/co">co</a> and async/await as
-a convenience. If you need
-a fully-fledged promise, use the <code>.exec()</code> function.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> query = Band.findOne({name: <span class="hljs-string">"Guns N' Roses"</span>});
-assert.ok(!(query <span class="hljs-keyword">instanceof</span> <span class="hljs-built_in">Promise</span>));
-
-<span class="hljs-comment">// A query is not a fully-fledged promise, but it does have a `.then()`.</span>
-query.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-comment">// use doc</span>
-});
-
-<span class="hljs-comment">// `.exec()` gives you a fully-fledged promise</span>
-<span class="hljs-keyword">var</span> promise = query.exec();
-assert.ok(promise <span class="hljs-keyword">instanceof</span> <span class="hljs-built_in">Promise</span>);
-
-promise.then(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-comment">// use doc</span>
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Plugging in your own Promises Library</a></h2><p>If you&#39;re an advanced user, you may want to plug in your own promise
-library like <a href="https://www.npmjs.com/package/bluebird">bluebird</a>. Just set
-<code>mongoose.Promise</code> to your favorite
-ES6-style promise constructor and mongoose will use it.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> query = Band.findOne({name: <span class="hljs-string">"Guns N' Roses"</span>});
-
-<span class="hljs-comment">// Use bluebird</span>
-mongoose.Promise = <span class="hljs-built_in">require</span>(<span class="hljs-string">'bluebird'</span>);
-assert.equal(query.exec().constructor, <span class="hljs-built_in">require</span>(<span class="hljs-string">'bluebird'</span>));
-
-<span class="hljs-comment">// Use q. Note that you **must** use `require('q').Promise`.</span>
-mongoose.Promise = <span class="hljs-built_in">require</span>(<span class="hljs-string">'q'</span>).Promise;
-assert.ok(query.exec() <span class="hljs-keyword">instanceof</span> <span class="hljs-built_in">require</span>(<span class="hljs-string">'q'</span>).makePromise);</code></pre>
-<div class="suffix">
-      <div>
-        <br>
-        <i>
-          Want to learn how to check whether your favorite npm modules work with
-          async/await without cobbling together contradictory answers from Google
-          and Stack Overflow? Chapter 4 of Mastering Async/Await explains the
-          basic principles for determining whether frameworks like React and
-          Mongoose support async/await.
-          <a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=promises">Get your copy!</a>
-        </i>
-        <br><br>
-        <a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=promises" style="margin-left: 100px">
-          <img src="/docs/images/asyncawait.png" style="width: 650px" />
-        </a>
-      </div>
-    </div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/queries.html b/docs/queries.html
deleted file mode 100644
index 9af1da99d72..00000000000
--- a/docs/queries.html
+++ /dev/null
@@ -1,195 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Queries</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="queries">Queries</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Mongoose <a href="./models.html">models</a> provide several static helper functions
-for <a href="https://en.wikipedia.org/wiki/Create,_read,_update_and_delete">CRUD operations</a>.
-Each of these functions returns a
-<a href="http://mongoosejs.com/docs/api.html#Query">mongoose <code>Query</code> object</a>.</p>
-<ul>
-<li><a href="/docs/api.html#model_Model.deleteMany"><code>Model.deleteMany()</code></a></li>
-<li><a href="/docs/api.html#model_Model.deleteOne"><code>Model.deleteOne()</code></a></li>
-<li><a href="/docs/api.html#model_Model.find"><code>Model.find()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findById"><code>Model.findById()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findByIdAndDelete"><code>Model.findByIdAndDelete()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findByIdAndRemove"><code>Model.findByIdAndRemove()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findByIdAndUpdate"><code>Model.findByIdAndUpdate()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOne"><code>Model.findOne()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOneAndDelete"><code>Model.findOneAndDelete()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOneAndRemove"><code>Model.findOneAndRemove()</code></a></li>
-<li><a href="/docs/api.html#model_Model.findOneAndUpdate"><code>Model.findOneAndUpdate()</code></a></li>
-<li><a href="/docs/api.html#model_Model.replaceOne"><code>Model.replaceOne()</code></a></li>
-<li><a href="/docs/api.html#model_Model.updateMany"><code>Model.updateMany()</code></a></li>
-<li><a href="/docs/api.html#model_Model.updateOne"><code>Model.updateOne()</code></a></li>
-</ul>
-<p>A mongoose query can be executed in one of two ways. First, if you
-pass in a <code>callback</code> function, Mongoose will execute the query asynchronously
-and pass the results to the <code>callback</code>.</p>
-<p>A query also has a <code>.then()</code> function, and thus can be used as a promise.</p>
-<ul class="toc">
-  <li><a href="#executing">Executing</a></li>
-  <li><a href="#queries-are-not-promises">Queries are Not Promises</a></li>
-  <li><a href="#connection-string-options">Connection String Options</a></li>
-  <li><a href="#refs">References to other documents</a></li>
-  <li><a href="#streaming">Streaming</a></li>
-</ul>
-
-<h3 id="executing">Executing</h3>
-<p>When executing a query with a <code>callback</code> function, you specify your query as a JSON document. The JSON document&#39;s syntax is the same as the <a href="http://docs.mongodb.org/manual/tutorial/query-documents/">MongoDB shell</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, yourSchema);
-
-<span class="hljs-comment">// find each person with a last name matching 'Ghost', selecting the `name` and `occupation` fields</span>
-Person.findOne({ <span class="hljs-string">'name.last'</span>: <span class="hljs-string">'Ghost'</span> }, <span class="hljs-string">'name occupation'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, person</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-comment">// Prints "Space Ghost is a talk show host".</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s %s is a %s.'</span>, person.name.first, person.name.last,
-    person.occupation);
-});</code></pre>
-<p>Mongoose executed the query and passed the results passed to <code>callback</code>. All callbacks in Mongoose use the pattern:
-<code>callback(error, result)</code>. If an error occurs executing the query, the <code>error</code> parameter will contain an error document, and <code>result</code>
-will be null. If the query is successful, the <code>error</code> parameter will be null, and the <code>result</code> will be populated with the results of the query.</p>
-<p>Anywhere a callback is passed to a query in Mongoose, the callback follows the pattern <code>callback(error, results)</code>. What <code>results</code> is depends on the operation: For <code>findOne()</code> it is a <a href="./api.html#model_Model.findOne">potentially-null single document</a>, <code>find()</code> a <a href="./api.html#model_Model.find">list of documents</a>, <code>count()</code> <a href="./api.html#model_Model.count">the number of documents</a>, <code>update()</code> the <a href="./api.html#model_Model.update">number of documents affected</a>, etc. The <a href="./api.html#model-js">API docs for Models</a> provide more detail on what is passed to the callbacks.</p>
-<p>Now let&#39;s look at what happens when no <code>callback</code> is passed:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// find each person with a last name matching 'Ghost'</span>
-<span class="hljs-keyword">var</span> query = Person.findOne({ <span class="hljs-string">'name.last'</span>: <span class="hljs-string">'Ghost'</span> });
-
-<span class="hljs-comment">// selecting the `name` and `occupation` fields</span>
-query.select(<span class="hljs-string">'name occupation'</span>);
-
-<span class="hljs-comment">// execute the query at a later time</span>
-query.exec(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, person</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-comment">// Prints "Space Ghost is a talk show host."</span>
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'%s %s is a %s.'</span>, person.name.first, person.name.last,
-    person.occupation);
-});</code></pre>
-<p>In the above code, the <code>query</code> variable is of type <a href="./api.html#query-js">Query</a>.
-A <code>Query</code> enables you to build up a query using chaining syntax, rather than specifying a JSON object.
-The below 2 examples are equivalent.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// With a JSON doc</span>
-Person.
-  find({
-    occupation: <span class="hljs-regexp">/host/</span>,
-    <span class="hljs-string">'name.last'</span>: <span class="hljs-string">'Ghost'</span>,
-    age: { $gt: <span class="hljs-number">17</span>, $lt: <span class="hljs-number">66</span> },
-    likes: { $<span class="hljs-keyword">in</span>: [<span class="hljs-string">'vaporizing'</span>, <span class="hljs-string">'talking'</span>] }
-  }).
-  limit(<span class="hljs-number">10</span>).
-  sort({ occupation: <span class="hljs-number">-1</span> }).
-  select({ name: <span class="hljs-number">1</span>, occupation: <span class="hljs-number">1</span> }).
-  exec(callback);
-
-<span class="hljs-comment">// Using query builder</span>
-Person.
-  find({ occupation: <span class="hljs-regexp">/host/</span> }).
-  where(<span class="hljs-string">'name.last'</span>).equals(<span class="hljs-string">'Ghost'</span>).
-  where(<span class="hljs-string">'age'</span>).gt(<span class="hljs-number">17</span>).lt(<span class="hljs-number">66</span>).
-  where(<span class="hljs-string">'likes'</span>).in([<span class="hljs-string">'vaporizing'</span>, <span class="hljs-string">'talking'</span>]).
-  limit(<span class="hljs-number">10</span>).
-  sort(<span class="hljs-string">'-occupation'</span>).
-  select(<span class="hljs-string">'name occupation'</span>).
-  exec(callback);</code></pre>
-<p>A full list of <a href="./api.html#query-js">Query helper functions can be found in the API docs</a>.</p>
-<h3 id="queries-are-not-promises">
-  <a href="#queries-are-not-promises">
-    Queries are Not Promises
-  </a>
-</h3>
-
-<p>Mongoose queries are <strong>not</strong> promises. They have a <code>.then()</code>
-function for <a href="https://www.npmjs.com/package/co">co</a> and
-<a href="http://thecodebarbarian.com/common-async-await-design-patterns-in-node.js.html">async/await</a>
-as a convenience. However, unlike promises, calling a query&#39;s <code>.then()</code>
-can execute the query multiple times.</p>
-<p>For example, the below code will execute 3 <code>updateMany()</code> calls, one
-because of the callback, and two because <code>.then()</code> is called twice.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> q = MyModel.updateMany({}, { isDeleted: <span class="hljs-literal">true</span> }, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Update 1'</span>);
-});
-
-q.then(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Update 2'</span>));
-q.then(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Update 3'</span>));</code></pre>
-<p>Don&#39;t mix using callbacks and promises with queries, or you may end up
-with duplicate operations.</p>
-<h3 id="refs"><a href="#refs">References to other documents</a></h3>
-
-<p>There are no joins in MongoDB but sometimes we still want references to
-documents in other collections. This is where <a href="./populate.html">population</a>
-comes in. Read more about how to include documents from other collections in
-your query results <a href="./api.html#query_Query-populate">here</a>.</p>
-<h3 id="streaming"><a href="#streaming">Streaming</a></h3>
-
-<p>You can <a href="http://nodejs.org/api/stream.html">stream</a> query results from
-MongoDB. You need to call the
-<a href="./api.html#query_Query-cursor">Query#cursor()</a> function to return an instance of
-<a href="./api.html#query_Query-cursor">QueryCursor</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> cursor = Person.find({ occupation: <span class="hljs-regexp">/host/</span> }).cursor();
-cursor.on(<span class="hljs-string">'data'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">doc</span>) </span>{
-  <span class="hljs-comment">// Called once for every document</span>
-});
-cursor.on(<span class="hljs-string">'close'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// Called when done</span>
-});</code></pre>
-<h3 id="next"><a href="#next">Next Up</a></h3>
-
-<p>Now that we&#39;ve covered <code>Queries</code>, let&#39;s take a look at <a href="/docs/validation.html">Validation</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/schematypes.html b/docs/schematypes.html
deleted file mode 100644
index 5d1c01233a0..00000000000
--- a/docs/schematypes.html
+++ /dev/null
@@ -1,539 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: SchemaTypes</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="schematypes"><a href="#schematypes">SchemaTypes</a></h2>
-
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>SchemaTypes handle definition of path
-<a href="./api.html#schematype_SchemaType-default">defaults</a>,
-<a href="./api.html#schematype_SchemaType-validate">validation</a>,
-<a href="#getters">getters</a>,
-<a href="./api.html#schematype_SchemaType-set">setters</a>,
-<a href="./api.html#schematype_SchemaType-select">field selection defaults</a> for
-<a href="./api.html#query-js">queries</a>,
-and other general characteristics for Mongoose document properties.</p>
-<ul class="toc">
-  <li><a href="#what-is-a-schema-type">What is a SchemaType?</a></li>
-  <li><a href="#schematype-options">SchemaType Options</a></li>
-  <li><a href="#customtypes">Creating Custom Types</a></li>
-  <li><a href="#path">The `schema.path()` Function</a></li>
-</ul>
-
-<h3 id="what-is-a-schematype"><a href="#what-is-a-schematype">What is a SchemaType?</a></h3>
-
-<p>You can think of a Mongoose schema as the configuration object for a
-Mongoose model. A SchemaType is then a configuration object for an individual
-property. A SchemaType says what type a given
-path should have, whether it has any getters/setters, and what values are
-valid for that path.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-schema.path(<span class="hljs-string">'name'</span>) <span class="hljs-keyword">instanceof</span> mongoose.SchemaType; <span class="hljs-comment">// true</span>
-schema.path(<span class="hljs-string">'name'</span>) <span class="hljs-keyword">instanceof</span> mongoose.Schema.Types.String; <span class="hljs-comment">// true</span>
-schema.path(<span class="hljs-string">'name'</span>).instance; <span class="hljs-comment">// 'String'</span></code></pre>
-<p>A SchemaType is different from a type. In other words, <code>mongoose.ObjectId !== mongoose.Types.ObjectId</code>.
-A SchemaType is just a configuration object for Mongoose. An instance of
-the <code>mongoose.ObjectId</code> SchemaType doesn&#39;t actually create MongoDB ObjectIds,
-it is just a configuration for a path in a schema.</p>
-<p>The following are all the valid SchemaTypes in Mongoose. Mongoose plugins
-can also add custom SchemaTypes like <a href="http://plugins.mongoosejs.io/plugins/int32">int32</a>.
-Check out <a href="http://plugins.mongoosejs.io">Mongoose&#39;s plugins search</a> to find plugins.</p>
-<ul>
-<li><a href="#strings">String</a></li>
-<li><a href="#numbers">Number</a></li>
-<li><a href="#dates">Date</a></li>
-<li><a href="#buffers">Buffer</a></li>
-<li><a href="#booleans">Boolean</a></li>
-<li><a href="#mixed">Mixed</a></li>
-<li><a href="#objectids">ObjectId</a></li>
-<li><a href="#arrays">Array</a></li>
-<li><a href="./api.html#Decimal128">Decimal128</a></li>
-<li><a href="#maps">Map</a></li>
-</ul>
-<h4>Example</h4>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name:    <span class="hljs-built_in">String</span>,
-  binary:  Buffer,
-  living:  <span class="hljs-built_in">Boolean</span>,
-  updated: { type: <span class="hljs-built_in">Date</span>, <span class="hljs-keyword">default</span>: <span class="hljs-built_in">Date</span>.now },
-  age:     { type: <span class="hljs-built_in">Number</span>, min: <span class="hljs-number">18</span>, max: <span class="hljs-number">65</span> },
-  mixed:   Schema.Types.Mixed,
-  _someId: Schema.Types.ObjectId,
-  decimal: Schema.Types.Decimal128,
-  array: [],
-  ofString: [<span class="hljs-built_in">String</span>],
-  ofNumber: [<span class="hljs-built_in">Number</span>],
-  ofDates: [<span class="hljs-built_in">Date</span>],
-  ofBuffer: [Buffer],
-  ofBoolean: [<span class="hljs-built_in">Boolean</span>],
-  ofMixed: [Schema.Types.Mixed],
-  ofObjectId: [Schema.Types.ObjectId],
-  ofArrays: [[]],
-  ofArrayOfNumbers: [[<span class="hljs-built_in">Number</span>]],
-  nested: {
-    stuff: { type: <span class="hljs-built_in">String</span>, lowercase: <span class="hljs-literal">true</span>, trim: <span class="hljs-literal">true</span> }
-  },
-  map: <span class="hljs-built_in">Map</span>,
-  mapOfString: {
-    type: <span class="hljs-built_in">Map</span>,
-    <span class="hljs-keyword">of</span>: <span class="hljs-built_in">String</span>
-  }
-})
-
-<span class="hljs-comment">// example use</span>
-
-<span class="hljs-keyword">var</span> Thing = mongoose.model(<span class="hljs-string">'Thing'</span>, schema);
-
-<span class="hljs-keyword">var</span> m = <span class="hljs-keyword">new</span> Thing;
-m.name = <span class="hljs-string">'Statue of Liberty'</span>;
-m.age = <span class="hljs-number">125</span>;
-m.updated = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>;
-m.binary = Buffer.alloc(<span class="hljs-number">0</span>);
-m.living = <span class="hljs-literal">false</span>;
-m.mixed = { any: { thing: <span class="hljs-string">'i want'</span> } };
-m.markModified(<span class="hljs-string">'mixed'</span>);
-m._someId = <span class="hljs-keyword">new</span> mongoose.Types.ObjectId;
-m.array.push(<span class="hljs-number">1</span>);
-m.ofString.push(<span class="hljs-string">"strings!"</span>);
-m.ofNumber.unshift(<span class="hljs-number">1</span>,<span class="hljs-number">2</span>,<span class="hljs-number">3</span>,<span class="hljs-number">4</span>);
-m.ofDates.addToSet(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>);
-m.ofBuffer.pop();
-m.ofMixed = [<span class="hljs-number">1</span>, [], <span class="hljs-string">'three'</span>, { four: <span class="hljs-number">5</span> }];
-m.nested.stuff = <span class="hljs-string">'good'</span>;
-m.map = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Map</span>([[<span class="hljs-string">'key'</span>, <span class="hljs-string">'value'</span>]]);
-m.save(callback);</code></pre>
-<h3 id="schematype-options"><a href="#schematype-options">SchemaType Options</a></h3>
-
-<p>You can declare a schema type using the type directly, or an object with
-a <code>type</code> property.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema1 = <span class="hljs-keyword">new</span> Schema({
-  test: <span class="hljs-built_in">String</span> <span class="hljs-comment">// `test` is a path of type String</span>
-});
-
-<span class="hljs-keyword">var</span> schema2 = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// The `test` object contains the "SchemaType options"</span>
-  test: { type: <span class="hljs-built_in">String</span> } <span class="hljs-comment">// `test` is a path of type string</span>
-});</code></pre>
-<p>In addition to the type property, you can specify additional properties
-for a path. For example, if you want to lowercase a string before saving:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema2 = <span class="hljs-keyword">new</span> Schema({
-  test: {
-    type: <span class="hljs-built_in">String</span>,
-    lowercase: <span class="hljs-literal">true</span> <span class="hljs-comment">// Always convert `test` to lowercase</span>
-  }
-});</code></pre>
-<p>You can add any property you want to your SchemaType options. Many plugins
-rely on custom SchemaType options. For example, the <a href="http://plugins.mongoosejs.io/plugins/autopopulate">mongoose-autopopulate</a>
-plugin automatically populates paths if you set <code>autopopulate: true</code> in your
-SchemaType options. Mongoose comes with support for several built-in
-SchemaType options, like <code>lowercase</code> in the above example.</p>
-<p>The <code>lowercase</code> option only works for strings. There are certain options
-which apply for all schema types, and some that apply for specific schema
-types.</p>
-<h5>All Schema Types</h5>
-
-<ul>
-<li><code>required</code>: boolean or function, if true adds a <a href="./validation.html#built-in-validators">required validator</a> for this property</li>
-<li><code>default</code>: Any or function, sets a default value for the path. If the value is a function, the return value of the function is used as the default.</li>
-<li><code>select</code>: boolean, specifies default <a href="https://docs.mongodb.com/manual/tutorial/project-fields-from-query-results/">projections</a> for queries</li>
-<li><code>validate</code>: function, adds a <a href="./validation.html#built-in-validators">validator function</a> for this property</li>
-<li><code>get</code>: function, defines a custom getter for this property using <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty"><code>Object.defineProperty()</code></a>.</li>
-<li><code>set</code>: function, defines a custom setter for this property using <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty"><code>Object.defineProperty()</code></a>.</li>
-<li><code>alias</code>: string, mongoose &gt;= 4.10.0 only. Defines a <a href="./guide.html#virtuals">virtual</a> with the given name that gets/sets this path.</li>
-</ul>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> numberSchema = <span class="hljs-keyword">new</span> Schema({
-  integerOnly: {
-    type: <span class="hljs-built_in">Number</span>,
-    get: v =&gt; <span class="hljs-built_in">Math</span>.round(v),
-    set: v =&gt; <span class="hljs-built_in">Math</span>.round(v),
-    alias: <span class="hljs-string">'i'</span>
-  }
-});
-
-<span class="hljs-keyword">var</span> <span class="hljs-built_in">Number</span> = mongoose.model(<span class="hljs-string">'Number'</span>, numberSchema);
-
-<span class="hljs-keyword">var</span> doc = <span class="hljs-keyword">new</span> <span class="hljs-built_in">Number</span>();
-doc.integerOnly = <span class="hljs-number">2.001</span>;
-doc.integerOnly; <span class="hljs-comment">// 2</span>
-doc.i; <span class="hljs-comment">// 2</span>
-doc.i = <span class="hljs-number">3.001</span>;
-doc.integerOnly; <span class="hljs-comment">// 3</span>
-doc.i; <span class="hljs-comment">// 3</span></code></pre>
-<h5>Indexes</h5>
-
-<p>You can also define <a href="https://docs.mongodb.com/manual/indexes/">MongoDB indexes</a>
-using schema type options.</p>
-<ul>
-<li><code>index</code>: boolean, whether to define an <a href="https://docs.mongodb.com/manual/indexes/">index</a> on this property.</li>
-<li><code>unique</code>: boolean, whether to define a <a href="https://docs.mongodb.com/manual/core/index-unique/">unique index</a> on this property.</li>
-<li><code>sparse</code>: boolean, whether to define a <a href="https://docs.mongodb.com/manual/core/index-sparse/">sparse index</a> on this property.</li>
-</ul>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema2 = <span class="hljs-keyword">new</span> Schema({
-  test: {
-    type: <span class="hljs-built_in">String</span>,
-    index: <span class="hljs-literal">true</span>,
-    unique: <span class="hljs-literal">true</span> <span class="hljs-comment">// Unique index. If you specify `unique: true`</span>
-    <span class="hljs-comment">// specifying `index: true` is optional if you do `unique: true`</span>
-  }
-});</code></pre>
-<h5 id="string-validators">String</h5>
-
-<ul>
-<li><code>lowercase</code>: boolean, whether to always call <code>.toLowerCase()</code> on the value</li>
-<li><code>uppercase</code>: boolean, whether to always call <code>.toUpperCase()</code> on the value</li>
-<li><code>trim</code>: boolean, whether to always call <code>.trim()</code> on the value</li>
-<li><code>match</code>: RegExp, creates a <a href="./validation.html">validator</a> that checks if the value matches the given regular expression</li>
-<li><code>enum</code>: Array, creates a <a href="./validation.html">validator</a> that checks if the value is in the given array.</li>
-<li><code>minlength</code>: Number, creates a <a href="./validation.html">validator</a> that checks if the value length is not less than the given number</li>
-<li><code>maxlength</code>: Number, creates a <a href="./validation.html">validator</a> that checks if the value length is not greater than the given number</li>
-</ul>
-<h5 id="number-validators">Number</h5>
-
-<ul>
-<li><code>min</code>: Number, creates a <a href="./validation.html">validator</a> that checks if the value is greater than or equal to the given minimum.</li>
-<li><code>max</code>: Number, creates a <a href="./validation.html">validator</a> that checks if the value is less than or equal to the given maximum.</li>
-</ul>
-<h5>Date</h5>
-
-<ul>
-<li><code>min</code>: Date</li>
-<li><code>max</code>: Date</li>
-</ul>
-<h3 id="usage-notes"><a href="#usage-notes">Usage notes</a></h3>
-
-<h4 id="strings">String</h4>
-
-<p>To declare a path as a string, you may use either the <code>String</code> global
-constructor or the string <code>&#39;String&#39;</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema1 = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }); <span class="hljs-comment">// name will be cast to string</span>
-<span class="hljs-keyword">const</span> schema2 = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-string">'String'</span> }); <span class="hljs-comment">// Equivalent</span>
-
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, schema2);</code></pre>
-<p>If you pass an element that has a <code>toString()</code> function, Mongoose will call it,
-unless the <code>toString()</code> function is strictly equal to <code>Object.prototype.toString()</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Person({ name: <span class="hljs-number">42</span> }).name; <span class="hljs-comment">// "42" as a string</span>
-<span class="hljs-keyword">new</span> Person({ name: { toString: () =&gt; <span class="hljs-number">42</span> } }).name; <span class="hljs-comment">// "42" as a string</span>
-
-<span class="hljs-comment">// "undefined", will get a cast error if you `save()` this document </span>
-<span class="hljs-keyword">new</span> Person({ name: { foo: <span class="hljs-number">42</span> } }).name; </code></pre>
-<h4 id="numbers">Number</h4>
-
-<p>To declare a path as a number, you may use either the <code>Number</code> global
-constructor or the string <code>&#39;Number&#39;</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema1 = <span class="hljs-keyword">new</span> Schema({ age: <span class="hljs-built_in">Number</span> }); <span class="hljs-comment">// age will be cast to a Number</span>
-<span class="hljs-keyword">const</span> schema2 = <span class="hljs-keyword">new</span> Schema({ age: <span class="hljs-string">'Number'</span> }); <span class="hljs-comment">// Equivalent</span>
-
-<span class="hljs-keyword">const</span> Car = mongoose.model(<span class="hljs-string">'Car'</span>, schema2);</code></pre>
-<p>There are several types of values that will be successfully cast to a Number.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> Car({ age: <span class="hljs-string">'15'</span> }).age; <span class="hljs-comment">// 15 as a Number</span>
-<span class="hljs-keyword">new</span> Car({ age: <span class="hljs-literal">true</span> }).age; <span class="hljs-comment">// 1 as a Number</span>
-<span class="hljs-keyword">new</span> Car({ age: <span class="hljs-literal">false</span> }).age; <span class="hljs-comment">// 0 as a Number</span>
-<span class="hljs-keyword">new</span> Car({ age: { valueOf: () =&gt; <span class="hljs-number">83</span> } }).age; <span class="hljs-comment">// 83 as a Number</span></code></pre>
-<p>If you pass an object with a <code>valueOf()</code> function that returns a Number, Mongoose will
-call it and assign the returned value to the path.</p>
-<p>The values <code>null</code> and <code>undefined</code> are not cast.</p>
-<p>NaN, strings that cast to NaN, arrays, and objects that don&#39;t have a <code>valueOf()</code> function
-will all result in a <a href="/docs/api.html#mongooseerror_MongooseError.CastError">CastError</a>.</p>
-<h4 id="dates">Dates</h4>
-
-<p><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date">Built-in <code>Date</code> methods</a> are <a href="https://github.com/Automattic/mongoose/issues/1598"><strong>not</strong> hooked into</a> the mongoose change tracking logic which in English means that if you use a <code>Date</code> in your document and modify it with a method like <code>setMonth()</code>, mongoose will be unaware of this change and <code>doc.save()</code> will not persist this modification. If you must modify <code>Date</code> types using built-in methods, tell mongoose about the change with <code>doc.markModified(&#39;pathToYourDate&#39;)</code> before saving.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Assignment = mongoose.model(<span class="hljs-string">'Assignment'</span>, { dueDate: <span class="hljs-built_in">Date</span> });
-Assignment.findOne(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err, doc</span>) </span>{
-  doc.dueDate.setMonth(<span class="hljs-number">3</span>);
-  doc.save(callback); <span class="hljs-comment">// THIS DOES NOT SAVE YOUR CHANGE</span>
-
-  doc.markModified(<span class="hljs-string">'dueDate'</span>);
-  doc.save(callback); <span class="hljs-comment">// works</span>
-})</code></pre>
-<h4 id="buffers">Buffer</h4>
-
-<p>To declare a path as a Buffer, you may use either the <code>Buffer</code> global
-constructor or the string <code>&#39;Buffer&#39;</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema1 = <span class="hljs-keyword">new</span> Schema({ binData: Buffer }); <span class="hljs-comment">// binData will be cast to a Buffer</span>
-<span class="hljs-keyword">const</span> schema2 = <span class="hljs-keyword">new</span> Schema({ binData: <span class="hljs-string">'Buffer'</span> }); <span class="hljs-comment">// Equivalent</span>
-
-<span class="hljs-keyword">const</span> Data = mongoose.model(<span class="hljs-string">'Data'</span>, schema2);</code></pre>
-<p>Mongoose will successfully cast the below values to buffers.</p>
-<pre><code><span class="hljs-keyword">const</span> file1 = <span class="hljs-keyword">new</span> Data({ binData: <span class="hljs-string">'test'</span>}); <span class="hljs-comment">// {"type":"Buffer","data":[116,101,115,116]}</span>
-<span class="hljs-keyword">const</span> file2 = <span class="hljs-keyword">new</span> Data({ binData: <span class="hljs-number">72987</span> }); <span class="hljs-comment">// {"type":"Buffer","data":[27]}</span>
-<span class="hljs-keyword">const</span> file4 = <span class="hljs-keyword">new</span> Data({ binData: { type: <span class="hljs-string">'Buffer'</span>, data: [<span class="hljs-number">1</span>, <span class="hljs-number">2</span>, <span class="hljs-number">3</span>]}}); <span class="hljs-comment">// {"type":"Buffer","data":[1,2,3]}</span></code></pre><h4 id="mixed">Mixed</h4>
-
-<p>An &quot;anything goes&quot; SchemaType. Mongoose will not do any casting on mixed paths.
-You can define a mixed path using <code>Schema.Types.Mixed</code> or by passing an empty
-object literal. The following are equivalent.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> Any = <span class="hljs-keyword">new</span> Schema({ any: {} });
-<span class="hljs-keyword">const</span> Any = <span class="hljs-keyword">new</span> Schema({ any: <span class="hljs-built_in">Object</span> });
-<span class="hljs-keyword">const</span> Any = <span class="hljs-keyword">new</span> Schema({ any: Schema.Types.Mixed });
-<span class="hljs-keyword">const</span> Any = <span class="hljs-keyword">new</span> Schema({ any: mongoose.Mixed });
-<span class="hljs-comment">// Note that if you're using `type`, putting _any_ POJO as the `type` will</span>
-<span class="hljs-comment">// make the path mixed.</span>
-<span class="hljs-keyword">const</span> Any = <span class="hljs-keyword">new</span> Schema({
-  any: {
-    type: { foo: <span class="hljs-built_in">String</span> }
-  }
-});</code></pre>
-<p>Since it is a schema-less type, you can change the value to anything else you
-like, but Mongoose loses the ability to auto detect and save those changes.
-To tell Mongoose that the value of a Mixed type has changed, you need to
-call <code>doc.markModified(path)</code>, passing the path to the Mixed type you just changed.</p>
-<pre><code class="language-javascript">person.anything = { x: [<span class="hljs-number">3</span>, <span class="hljs-number">4</span>, { y: <span class="hljs-string">"changed"</span> }] };
-person.markModified(<span class="hljs-string">'anything'</span>);
-person.save(); <span class="hljs-comment">// Mongoose will save changes to `anything`.</span></code></pre>
-<h4 id="objectids">ObjectIds</h4>
-
-<p>To specify a type of ObjectId, use <code>Schema.Types.ObjectId</code> in your declaration.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-<span class="hljs-keyword">var</span> ObjectId = mongoose.Schema.Types.ObjectId;
-<span class="hljs-keyword">var</span> Car = <span class="hljs-keyword">new</span> Schema({ driver: ObjectId });
-<span class="hljs-comment">// or just Schema.ObjectId for backwards compatibility with v2</span></code></pre>
-<h4 id="booleans">Boolean</h4>
-
-<p>Booleans in Mongoose are <a href="https://www.w3schools.com/js/js_booleans.asp">plain JavaScript booleans</a>.
-By default, Mongoose casts the below values to <code>true</code>:</p>
-<ul>
-<li><code>true</code></li>
-<li><code>&#39;true&#39;</code></li>
-<li><code>1</code></li>
-<li><code>&#39;1&#39;</code></li>
-<li><code>&#39;yes&#39;</code></li>
-</ul>
-<p>Mongoose casts the below values to <code>false</code>:</p>
-<ul>
-<li><code>false</code></li>
-<li><code>&#39;false&#39;</code></li>
-<li><code>0</code></li>
-<li><code>&#39;0&#39;</code></li>
-<li><code>&#39;no&#39;</code></li>
-</ul>
-<p>Any other value causes a <a href="/docs/api.html#mongooseerror_MongooseError.CastError">CastError</a>.
-You can modify what values Mongoose converts to true or false using the
-<code>convertToTrue</code> and <code>convertToFalse</code> properties, which are <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set">JavaScript sets</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> M = mongoose.model(<span class="hljs-string">'Test'</span>, <span class="hljs-keyword">new</span> Schema({ b: <span class="hljs-built_in">Boolean</span> }));
-<span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">new</span> M({ b: <span class="hljs-string">'nay'</span> }).b); <span class="hljs-comment">// undefined</span>
-
-<span class="hljs-comment">// Set { false, 'false', 0, '0', 'no' }</span>
-<span class="hljs-built_in">console</span>.log(mongoose.Schema.Types.Boolean.convertToFalse);
-
-mongoose.Schema.Types.Boolean.convertToFalse.add(<span class="hljs-string">'nay'</span>);
-<span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">new</span> M({ b: <span class="hljs-string">'nay'</span> }).b); <span class="hljs-comment">// false</span></code></pre>
-<h4 id="arrays">Arrays</h4>
-
-<p>Mongoose supports arrays of <a href="./api.html#schema_Schema.Types">SchemaTypes</a>
-and arrays of <a href="./subdocs.html">subdocuments</a>. Arrays of SchemaTypes are
-also called <em>primitive arrays</em>, and arrays of subdocuments are also called
-<em>document arrays</em>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> ToySchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">var</span> ToyBoxSchema = <span class="hljs-keyword">new</span> Schema({
-  toys: [ToySchema],
-  buffers: [Buffer],
-  strings: [<span class="hljs-built_in">String</span>],
-  numbers: [<span class="hljs-built_in">Number</span>]
-  <span class="hljs-comment">// ... etc</span>
-});</code></pre>
-<p>Arrays are special because they implicitly have a default value of <code>[]</code> (empty array).</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> ToyBox = mongoose.model(<span class="hljs-string">'ToyBox'</span>, ToyBoxSchema);
-<span class="hljs-built_in">console</span>.log((<span class="hljs-keyword">new</span> ToyBox()).toys); <span class="hljs-comment">// []</span></code></pre>
-<p>To overwrite this default, you need to set the default value to <code>undefined</code></p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> ToyBoxSchema = <span class="hljs-keyword">new</span> Schema({
-  toys: {
-    type: [ToySchema],
-    <span class="hljs-keyword">default</span>: <span class="hljs-literal">undefined</span>
-  }
-});</code></pre>
-<p>Note: specifying an empty array is equivalent to <code>Mixed</code>. The following all create arrays of
-<code>Mixed</code>:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Empty1 = <span class="hljs-keyword">new</span> Schema({ any: [] });
-<span class="hljs-keyword">var</span> Empty2 = <span class="hljs-keyword">new</span> Schema({ any: <span class="hljs-built_in">Array</span> });
-<span class="hljs-keyword">var</span> Empty3 = <span class="hljs-keyword">new</span> Schema({ any: [Schema.Types.Mixed] });
-<span class="hljs-keyword">var</span> Empty4 = <span class="hljs-keyword">new</span> Schema({ any: [{}] });</code></pre>
-<h4 id="maps">Maps</h4>
-
-<p><em>New in Mongoose 5.1.0</em></p>
-<p>A <code>MongooseMap</code> is a subclass of the built-in <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map"><code>Map</code> class</a>.
-In these docs, we&#39;ll use the terms &#39;map&#39; and <code>MongooseMap</code> interchangeably.
-In Mongoose, maps are how you create a nested document with arbitrary keys.</p>
-<p><strong>Note</strong>: In Mongoose Maps, keys must be strings in order to store the document in MongoDB.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// `socialMediaHandles` is a map whose values are strings. A map's</span>
-  <span class="hljs-comment">// keys are always strings. You specify the type of values using `of`.</span>
-  socialMediaHandles: {
-    type: <span class="hljs-built_in">Map</span>,
-    <span class="hljs-keyword">of</span>: <span class="hljs-built_in">String</span>
-  }
-});
-
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-<span class="hljs-comment">// Map { 'github' =&gt; 'vkarpov15', 'twitter' =&gt; '@code_barbarian' }</span>
-<span class="hljs-built_in">console</span>.log(<span class="hljs-keyword">new</span> User({
-  socialMediaHandles: {
-    github: <span class="hljs-string">'vkarpov15'</span>,
-    twitter: <span class="hljs-string">'@code_barbarian'</span>
-  }
-}).socialMediaHandles);</code></pre>
-<p>The above example doesn&#39;t explicitly declare <code>github</code> or <code>twitter</code> as paths,
-but, since <code>socialMediaHandles</code> is a map, you can store arbitrary key/value
-pairs. However, since <code>socialMediaHandles</code> is a map, you <strong>must</strong> use
-<code>.get()</code> to get the value of a key and <code>.set()</code> to set the value of a key.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User({
-  socialMediaHandles: {}
-});
-
-<span class="hljs-comment">// Good</span>
-user.socialMediaHandles.set(<span class="hljs-string">'github'</span>, <span class="hljs-string">'vkarpov15'</span>);
-<span class="hljs-comment">// Works too</span>
-user.set(<span class="hljs-string">'socialMediaHandles.twitter'</span>, <span class="hljs-string">'@code_barbarian'</span>);
-<span class="hljs-comment">// Bad, the `myspace` property will **not** get saved</span>
-user.socialMediaHandles.myspace = <span class="hljs-string">'fail'</span>;
-
-<span class="hljs-comment">// 'vkarpov15'</span>
-<span class="hljs-built_in">console</span>.log(user.socialMediaHandles.get(<span class="hljs-string">'github'</span>));
-<span class="hljs-comment">// '@code_barbarian'</span>
-<span class="hljs-built_in">console</span>.log(user.get(<span class="hljs-string">'socialMediaHandles.twitter'</span>));
-<span class="hljs-comment">// undefined</span>
-user.socialMediaHandles.github;
-
-<span class="hljs-comment">// Will only save the 'github' and 'twitter' properties</span>
-user.save();</code></pre>
-<p>Map types are stored as <a href="https://en.wikipedia.org/wiki/BSON#Data_types_and_syntax">BSON objects in MongoDB</a>.
-Keys in a BSON object are ordered, so this means the <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#Description">insertion order</a>
-property of maps is maintained.</p>
-<h3 id="getters"><a href="#getters">Getters</a></h3>
-
-<p>Getters are like virtuals for paths defined in your schema. For example,
-let&#39;s say you wanted to store user profile pictures as relative paths and
-then add the hostname in your application. Below is how you would structure
-your <code>userSchema</code>:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> root = <span class="hljs-string">'https://s3.amazonaws.com/mybucket'</span>;
-
-<span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  name: <span class="hljs-built_in">String</span>,
-  picture: {
-    type: <span class="hljs-built_in">String</span>,
-    get: v =&gt; <span class="hljs-string">`<span class="hljs-subst">${root}</span><span class="hljs-subst">${v}</span>`</span>
-  }
-});
-
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> User({ name: <span class="hljs-string">'Val'</span>, picture: <span class="hljs-string">'/123.png'</span> });
-doc.picture; <span class="hljs-comment">// 'https://s3.amazonaws.com/mybucket/123.png'</span>
-doc.toObject({ getters: <span class="hljs-literal">false</span> }).picture; <span class="hljs-comment">// '123.png'</span></code></pre>
-<p>Generally, you only use getters on primitive paths as opposed to arrays
-or subdocuments. Because getters override what accessing a Mongoose path returns,
-declaring a getter on an object may remove Mongoose change tracking for
-that path.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  arr: [{ url: <span class="hljs-built_in">String</span> }]
-});
-
-<span class="hljs-keyword">const</span> root = <span class="hljs-string">'https://s3.amazonaws.com/mybucket'</span>;
-
-<span class="hljs-comment">// Bad, don't do this!</span>
-schema.path(<span class="hljs-string">'arr'</span>).get(v =&gt; {
-  <span class="hljs-keyword">return</span> v.map(el =&gt; <span class="hljs-built_in">Object</span>.assign(el, { url: root + el.url }));
-});
-
-<span class="hljs-comment">// Later</span>
-doc.arr.push({ key: <span class="hljs-built_in">String</span> });
-doc.arr[<span class="hljs-number">0</span>]; <span class="hljs-comment">// 'undefined' because every `doc.arr` creates a new array!</span></code></pre>
-<p>Instead of declaring a getter on the array as shown above, you should
-declare a getter on the <code>url</code> string as shown below. If you need to declare
-a getter on a nested document or array, be very careful!</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  arr: [{ url: <span class="hljs-built_in">String</span> }]
-});
-
-<span class="hljs-keyword">const</span> root = <span class="hljs-string">'https://s3.amazonaws.com/mybucket'</span>;
-
-<span class="hljs-comment">// Good, do this instead of declaring a getter on `arr`</span>
-schema.path(<span class="hljs-string">'arr.0.url'</span>).get(v =&gt; <span class="hljs-string">`<span class="hljs-subst">${root}</span><span class="hljs-subst">${v}</span>`</span>);</code></pre>
-<h3 id="customtypes"><a href="#customtypes">Creating Custom Types</a></h3>
-
-<p>Mongoose can also be extended with <a href="customschematypes.html">custom SchemaTypes</a>. Search the
-<a href="http://plugins.mongoosejs.io">plugins</a>
-site for compatible types like
-<a href="https://github.com/aheckmann/mongoose-long">mongoose-long</a>,
-<a href="https://github.com/vkarpov15/mongoose-int32">mongoose-int32</a>,
-and
-<a href="https://github.com/aheckmann/mongoose-function">other</a>
-<a href="https://github.com/OpenifyIt/mongoose-types">types</a>.</p>
-<p>Read more about creating <a href="customschematypes.html">custom SchemaTypes here</a>.</p>
-<h3 id="path"><a href="#path">The `schema.path()` Function</a></h3>
-
-<p>The <code>schema.path()</code> function returns the instantiated schema type for a
-given path.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> sampleSchema = <span class="hljs-keyword">new</span> Schema({ name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> } });
-<span class="hljs-built_in">console</span>.log(sampleSchema.path(<span class="hljs-string">'name'</span>));
-<span class="hljs-comment">// Output looks like:</span>
-<span class="hljs-comment">/**
- * SchemaString {
- *   enumValues: [],
- *   regExp: null,
- *   path: 'name',
- *   instance: 'String',
- *   validators: ...
- */</span></code></pre>
-<p>You can use this function to inspect the schema type for a given path,
-including what validators it has and what the type is.</p>
-<h3 id="next"><a href="#next">Next Up</a></h3>
-
-<p>Now that we&#39;ve covered <code>SchemaTypes</code>, let&#39;s take a look at <a href="/docs/connections.html">Connections</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/search.html b/docs/search.html
deleted file mode 100644
index b9de2769480..00000000000
--- a/docs/search.html
+++ /dev/null
@@ -1,100 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Search</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><script type="text/javascript" src="https://unpkg.com/unfetch/polyfill"></script><style>.search-bar {
-  margin-top: 1em;
-}
-
-.search-bar input {
-  width: 810px;
-  border: 1px solid #ddd;
-  padding: 0.25em;
-  border-radius: 3px;
-}
-
-.search-bar button {
-  background-color: #777;
-  color: white;
-  border: 1px solid transparent;
-  border-radius: 3px;
-  height: 30px;
-  width: 30px;
-  padding: 0px;
-  position: relative;
-  top: 7px;
-  left: 1px;
-}
-
-.title {
-  font-size: 1.5em;
-}
-
-ul {
-  list-style-type: none;
-  padding: 0px;
-}
-
-.url a {
-  font-size: 0.75em;
-  color: #777;
-  margin-top: 0.5em;
-}
-
-p {
-  margin-top: 0.5em;
-  line-height: 1.5em;
-}
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><div><h2>Search</h2><script>_native.init("CK7DT53U",{
-  targetClass: 'native-inline'
-});
-</script><div class="native-inline"><a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div><div class="search-bar"><input id="search-input" type="text" placeholder="Search"><button id="search-button"><img src="/docs/images/search.svg"></button></div><div id="results"></div><script type="text/javascript" src="/docs/js/search.js"></script></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/subdocs.html b/docs/subdocs.html
deleted file mode 100644
index 1f790de50dc..00000000000
--- a/docs/subdocs.html
+++ /dev/null
@@ -1,227 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: SubDocuments</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h2 id="subdocuments">Subdocuments</h2>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Subdocuments are documents embedded in other documents. In Mongoose, this
-means you can nest schemas in other schemas. Mongoose has two
-distinct notions of subdocuments: arrays of subdocuments and single nested
-subdocuments.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> childSchema = <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-string">'string'</span> });
-
-<span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> Schema({
-  <span class="hljs-comment">// Array of subdocuments</span>
-  children: [childSchema],
-  <span class="hljs-comment">// Single nested subdocuments. Caveat: single nested subdocs only work</span>
-  <span class="hljs-comment">// in mongoose &gt;= 4.2.0</span>
-  child: childSchema
-});</code></pre>
-<ul class="toc">
-  <li><a href="#what-is-a-subdocument-">What is a Subdocument?</a></li>
-  <li><a href="#finding-a-subdocument">Finding a Subdocument</a></li>
-  <li><a href="#adding-subdocs-to-arrays">Adding Subdocs to Arrays</a></li>
-  <li><a href="#removing-subdocs">Removing Subdocs</a></li>
-  <li><a href="#subdoc-parents">Parents of Subdocs</a></li>
-  <li><a href="#altsyntax">Alternate declaration syntax for arrays</a></li>
-</ul>
-
-<h3 id="what-is-a-subdocument">What is a Subdocument?</h3>
-<p>Subdocuments are similar to normal documents. Nested schemas can have
-<a href="./middleware.html">middleware</a>, <a href="./validation.html">custom validation logic</a>,
-virtuals, and any other feature top-level schemas can use. The major
-difference is that subdocuments are
-not saved individually, they are saved whenever their top-level parent
-document is saved.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Parent = mongoose.model(<span class="hljs-string">'Parent'</span>, parentSchema);
-<span class="hljs-keyword">var</span> parent = <span class="hljs-keyword">new</span> Parent({ children: [{ name: <span class="hljs-string">'Matt'</span> }, { name: <span class="hljs-string">'Sarah'</span> }] })
-parent.children[<span class="hljs-number">0</span>].name = <span class="hljs-string">'Matthew'</span>;
-
-<span class="hljs-comment">// `parent.children[0].save()` is a no-op, it triggers middleware but</span>
-<span class="hljs-comment">// does **not** actually save the subdocument. You need to save the parent</span>
-<span class="hljs-comment">// doc.</span>
-parent.save(callback);</code></pre>
-<p>Subdocuments have <code>save</code> and <code>validate</code> <a href="./middleware.html">middleware</a>
-just like top-level documents. Calling <code>save()</code> on the parent document triggers
-the <code>save()</code> middleware for all its subdocuments, and the same for <code>validate()</code>
-middleware.</p>
-<pre><code class="language-javascript">childSchema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-keyword">if</span> (<span class="hljs-string">'invalid'</span> == <span class="hljs-keyword">this</span>.name) {
-    <span class="hljs-keyword">return</span> next(<span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'#sadpanda'</span>));
-  }
-  next();
-});
-
-<span class="hljs-keyword">var</span> parent = <span class="hljs-keyword">new</span> Parent({ children: [{ name: <span class="hljs-string">'invalid'</span> }] });
-parent.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(err.message) <span class="hljs-comment">// #sadpanda</span>
-});</code></pre>
-<p>Subdocuments&#39; <code>pre(&#39;save&#39;)</code> and <code>pre(&#39;validate&#39;)</code> middleware execute
-<strong>before</strong> the top-level document&#39;s <code>pre(&#39;save&#39;)</code> but <strong>after</strong> the
-top-level document&#39;s <code>pre(&#39;validate&#39;)</code> middleware. This is because validating
-before <code>save()</code> is actually a piece of built-in middleware.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Below code will print out 1-4 in order</span>
-<span class="hljs-keyword">var</span> childSchema = <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-string">'string'</span> });
-
-childSchema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'2'</span>);
-  next();
-});
-
-childSchema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'3'</span>);
-  next();
-});
-
-<span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  child: childSchema,
-    });
-
-parentSchema.pre(<span class="hljs-string">'validate'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'1'</span>);
-  next();
-});
-
-parentSchema.pre(<span class="hljs-string">'save'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">next</span>) </span>{
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'4'</span>);
-  next();
-});</code></pre>
-<h3 id="finding-a-subdocument">Finding a Subdocument</h3><p>Each subdocument has an <code>_id</code> by default. Mongoose document arrays have a
-special <a href="./api.html#types_documentarray_MongooseDocumentArray-id">id</a> method
-for searching a document array to find a document with a given <code>_id</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> doc = parent.children.id(_id);</code></pre>
-<h3 id="adding-subdocs-to-arrays">Adding Subdocs to Arrays</h3><p>MongooseArray methods such as
-<a href="./api.html#mongoosearray_MongooseArray-push">push</a>,
-<a href="./api.html#mongoosearray_MongooseArray-unshift">unshift</a>,
-<a href="./api.html#mongoosearray_MongooseArray-addToSet">addToSet</a>,
-and others cast arguments to their proper types transparently:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> Parent = mongoose.model(<span class="hljs-string">'Parent'</span>);
-<span class="hljs-keyword">var</span> parent = <span class="hljs-keyword">new</span> Parent;
-
-<span class="hljs-comment">// create a comment</span>
-parent.children.push({ name: <span class="hljs-string">'Liesl'</span> });
-<span class="hljs-keyword">var</span> subdoc = parent.children[<span class="hljs-number">0</span>];
-<span class="hljs-built_in">console</span>.log(subdoc) <span class="hljs-comment">// { _id: '501d86090d371bab2c0341c5', name: 'Liesl' }</span>
-subdoc.isNew; <span class="hljs-comment">// true</span>
-
-parent.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err)
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'Success!'</span>);
-});</code></pre>
-<p>Subdocs may also be created without adding them to the array by using the
-<a href="./api.html#types_documentarray_MongooseDocumentArray.create">create</a>
-method of MongooseArrays.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> newdoc = parent.children.create({ name: <span class="hljs-string">'Aaron'</span> });</code></pre>
-<h3 id="removing-subdocs">Removing Subdocs</h3><p>Each subdocument has it&#39;s own
-<a href="./api.html#types_embedded_EmbeddedDocument-remove">remove</a> method. For
-an array subdocument, this is equivalent to calling <code>.pull()</code> on the
-subdocument. For a single nested subdocument, <code>remove()</code> is equivalent
-to setting the subdocument to <code>null</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Equivalent to `parent.children.pull(_id)`</span>
-parent.children.id(_id).remove();
-<span class="hljs-comment">// Equivalent to `parent.child = null`</span>
-parent.child.remove();
-parent.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-keyword">if</span> (err) <span class="hljs-keyword">return</span> handleError(err);
-  <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'the subdocs were removed'</span>);
-});</code></pre>
-<h3 id="subdoc-parents">Parents of Subdocs</h3><p>Sometimes, you need to get the parent of a subdoc. You can access the
-parent using the <code>parent()</code> function.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  docArr: [{ name: <span class="hljs-built_in">String</span> }],
-  singleNested: <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> })
-});
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({
-  docArr: [{ name: <span class="hljs-string">'foo'</span> }],
-  singleNested: { name: <span class="hljs-string">'bar'</span> }
-});
-
-doc.singleNested.parent() === doc; <span class="hljs-comment">// true</span>
-doc.docArr[<span class="hljs-number">0</span>].parent() === doc; <span class="hljs-comment">// true</span></code></pre>
-<p>If you have a deeply nested subdoc, you can access the top-level document
-using the <code>ownerDocument()</code> function.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> Schema({
-  level1: <span class="hljs-keyword">new</span> Schema({
-    level2: <span class="hljs-keyword">new</span> Schema({
-      test: <span class="hljs-built_in">String</span>
-    })
-  })
-});
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({ level1: { level2: <span class="hljs-string">'test'</span> } });
-
-doc.level1.level2.parent() === doc; <span class="hljs-comment">// false</span>
-doc.level1.level2.parent() === doc.level1; <span class="hljs-comment">// true</span>
-doc.level1.level2.ownerDocument() === doc; <span class="hljs-comment">// true</span></code></pre>
-<h4 id="altsyntax">Alternate declaration syntax for arrays</h4><p>If you create a schema with an array of objects, mongoose will automatically
-convert the object to a schema for you:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> Schema({
-  children: [{ name: <span class="hljs-string">'string'</span> }]
-});
-<span class="hljs-comment">// Equivalent</span>
-<span class="hljs-keyword">var</span> parentSchema = <span class="hljs-keyword">new</span> Schema({
-  children: [<span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-string">'string'</span> })]
-});</code></pre>
-<h3 id="next">Next Up</h3><p>Now that we&#39;ve covered Subdocuments, let&#39;s take a look at
-<a href="./queries.html">querying</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/transactions.html b/docs/transactions.html
deleted file mode 100644
index 32dc8227626..00000000000
--- a/docs/transactions.html
+++ /dev/null
@@ -1,217 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Transactions</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="transactions-in-mongoose">Transactions in Mongoose</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p><a href="https://www.mongodb.com/transactions">Transactions</a> are new in MongoDB
-4.0 and Mongoose 5.2.0. Transactions let you execute multiple operations
-in isolation and potentially undo all the operations if one of them fails.
-This guide will get you started using transactions with Mongoose.</p>
-<h2 id="your-first-transaction">Your First Transaction</h2>
-<p><a href="https://docs.mongodb.com/manual/replication/#transactions">MongoDB currently only supports transactions on replica sets</a>,
-not standalone servers. To run a
-<a href="http://thecodebarbarian.com/introducing-run-rs-zero-config-mongodb-runner.html">local replica set for development</a>
-on macOS, Linux or Windows, use npm to install
-<a href="https://www.npmjs.com/package/run-rs">run-rs</a> globally and run
-<code>run-rs --version 4.0.0</code>. Run-rs will download MongoDB 4.0.0 for you.</p>
-<p>To use transactions with Mongoose, you should use Mongoose <code>&gt;= 5.2.0</code>. To
-check your current version of Mongoose, run <code>npm list | grep &quot;mongoose&quot;</code>
-or check the <a href="http://mongoosejs.com/docs/api.html#mongoose_Mongoose-version"><code>mongoose.version</code> property</a>.</p>
-<p>Transactions are built on <a href="https://docs.mongodb.com/manual/reference/server-sessions/">MongoDB sessions</a>.
-To start a transaction, you first need to call <a href="/docs/api.html#startsession_startSession"><code>startSession()</code></a>
-and then call the session&#39;s <code>startTransaction()</code> function. To execute an
-operation in a transaction, you need to pass the <code>session</code> as an option.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> Customer = db.model(<span class="hljs-string">'Customer'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-
-<span class="hljs-keyword">let</span> session = <span class="hljs-literal">null</span>;
-<span class="hljs-keyword">return</span> Customer.createCollection().
-  then(() =&gt; db.startSession()).
-  then(_session =&gt; {
-    session = _session;
-    <span class="hljs-comment">// Start a transaction</span>
-    session.startTransaction();
-    <span class="hljs-comment">// This `create()` is part of the transaction because of the `session`</span>
-    <span class="hljs-comment">// option.</span>
-    <span class="hljs-keyword">return</span> Customer.create([{ name: <span class="hljs-string">'Test'</span> }], { session: session });
-  }).
-  <span class="hljs-comment">// Transactions execute in isolation, so unless you pass a `session`</span>
-  <span class="hljs-comment">// to `findOne()` you won't see the document until the transaction</span>
-  <span class="hljs-comment">// is committed.</span>
-  then(() =&gt; Customer.findOne({ name: <span class="hljs-string">'Test'</span> })).
-  then(doc =&gt; assert.ok(!doc)).
-  <span class="hljs-comment">// This `findOne()` will return the doc, because passing the `session`</span>
-  <span class="hljs-comment">// means this `findOne()` will run as part of the transaction.</span>
-  then(() =&gt; Customer.findOne({ name: <span class="hljs-string">'Test'</span> }).session(session)).
-  then(doc =&gt; assert.ok(doc)).
-  <span class="hljs-comment">// Once the transaction is committed, the write operation becomes</span>
-  <span class="hljs-comment">// visible outside of the transaction.</span>
-  then(() =&gt; session.commitTransaction()).
-  then(() =&gt; Customer.findOne({ name: <span class="hljs-string">'Test'</span> })).
-  then(doc =&gt; assert.ok(doc));</code></pre>
-<h2 id="aborting-a-transaction">Aborting a Transaction</h2>
-<p>The most important feature of transactions is the ability to roll back <em>all</em>
-operations in the transaction using the <a href="https://docs.mongodb.com/manual/reference/method/Session.abortTransaction/"><code>abortTransaction()</code> function</a>.</p>
-<p>Think about <a href="https://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html#transactions-with-mongoose">modeling a bank account in Mongoose</a>.
-To transfer money from account <code>A</code> to account <code>B</code>, you would decrement
-<code>A</code>&#39;s balance and increment <code>B</code>&#39;s balance. However, if <code>A</code> only has a balance
-of $5 and you try to transfer $10, you want to abort the transaction and undo
-incrementing <code>B</code>&#39;s balance.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">let</span> session = <span class="hljs-literal">null</span>;
-<span class="hljs-keyword">return</span> Customer.createCollection().
-  then(() =&gt; Customer.startSession()).
-  then(_session =&gt; {
-    session = _session;
-    session.startTransaction();
-    <span class="hljs-keyword">return</span> Customer.create([{ name: <span class="hljs-string">'Test'</span> }], { session: session });
-  }).
-  then(() =&gt; Customer.create([{ name: <span class="hljs-string">'Test2'</span> }], { session: session })).
-  then(() =&gt; session.abortTransaction()).
-  then(() =&gt; Customer.countDocuments()).
-  then(count =&gt; assert.strictEqual(count, <span class="hljs-number">0</span>));</code></pre>
-<h2 id="the-withtransaction-helper">The <code>withTransaction()</code> Helper</h2>
-<p>The previous examples explicitly create a transaction and commits it. In
-practice, you&#39;ll want to use the <code>session.withTransaction()</code> helper
-instead. The <code>session.withTransaction()</code> helper handles creating a
-transaction, committing the transaction if it succeeds, aborting the transaction
-if your operation throws. It also handles <a href="https://stackoverflow.com/questions/52153538/what-is-a-transienttransactionerror-in-mongoose-or-mongodb">transient transaction errors</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">return</span> Customer.createCollection().
-  then(() =&gt; Customer.startSession()).
-  <span class="hljs-comment">// The `withTransaction()` function's first parameter is a function</span>
-  <span class="hljs-comment">// that returns a promise.</span>
-  then(session =&gt; session.withTransaction(() =&gt; {
-    <span class="hljs-keyword">return</span> Customer.create([{ name: <span class="hljs-string">'Test'</span> }], { session: session });
-  })).
-  then(() =&gt; Customer.countDocuments()).
-  then(count =&gt; assert.strictEqual(count, <span class="hljs-number">1</span>));</code></pre>
-<h2 id="with-mongoose-documents-and-save">With Mongoose Documents and <code>save()</code></h2>
-<p>If you get a <a href="/docs/documents.html">Mongoose document</a> from <a href="/docs/api.html#findone_findOne"><code>findOne()</code></a>
-or <a href="/docs/api.html#find_find"><code>find()</code></a> using a session, the document will
-keep a reference to the session and use that session for <a href="/docs/api.html#document_Document-save"><code>save()</code></a>.</p>
-<p>To get/set the session associated with a given document, use <a href="/docs/api.html#document_Document-$session"><code>doc.$session()</code></a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> User = db.model(<span class="hljs-string">'User'</span>, <span class="hljs-keyword">new</span> Schema({ name: <span class="hljs-built_in">String</span> }));
-
-<span class="hljs-keyword">let</span> session = <span class="hljs-literal">null</span>;
-<span class="hljs-keyword">return</span> User.createCollection().
-  then(() =&gt; db.startSession()).
-  then(_session =&gt; {
-    session = _session;
-    <span class="hljs-keyword">return</span> User.create({ name: <span class="hljs-string">'foo'</span> });
-  }).
-  then(() =&gt; {
-    session.startTransaction();
-    <span class="hljs-keyword">return</span> User.findOne({ name: <span class="hljs-string">'foo'</span> }).session(session);
-  }).
-  then(user =&gt; {
-    <span class="hljs-comment">// Getter/setter for the session associated with this document.</span>
-    assert.ok(user.$session());
-    user.name = <span class="hljs-string">'bar'</span>;
-    <span class="hljs-comment">// By default, `save()` uses the associated session</span>
-    <span class="hljs-keyword">return</span> user.save();
-  }).
-  then(() =&gt; User.findOne({ name: <span class="hljs-string">'bar'</span> })).
-  <span class="hljs-comment">// Won't find the doc because `save()` is part of an uncommitted transaction</span>
-  then(doc =&gt; assert.ok(!doc)).
-  then(() =&gt; {
-    session.commitTransaction();
-    <span class="hljs-keyword">return</span> User.findOne({ name: <span class="hljs-string">'bar'</span> });
-  }).
-  then(doc =&gt; assert.ok(doc));</code></pre>
-<h2 id="with-the-aggregation-framework">With the Aggregation Framework</h2>
-<p>The <code>Model.aggregate()</code> function also supports transactions. Mongoose
-aggregations have a <a href="/docs/api.html#aggregate_Aggregate-session"><code>session()</code> helper</a>
-that sets the <a href="/docs/api.html#aggregate_Aggregate-option"><code>session</code> option</a>.
-Below is an example of executing an aggregation within a transaction.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> Event = db.model(<span class="hljs-string">'Event'</span>, <span class="hljs-keyword">new</span> Schema({ createdAt: <span class="hljs-built_in">Date</span> }), <span class="hljs-string">'Event'</span>);
-
-<span class="hljs-keyword">let</span> session = <span class="hljs-literal">null</span>;
-<span class="hljs-keyword">return</span> Event.createCollection().
-  then(() =&gt; db.startSession()).
-  then(_session =&gt; {
-    session = _session;
-    session.startTransaction();
-    <span class="hljs-keyword">return</span> Event.insertMany([
-      { createdAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'2018-06-01'</span>) },
-      { createdAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'2018-06-02'</span>) },
-      { createdAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'2017-06-01'</span>) },
-      { createdAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'2017-05-31'</span>) }
-    ], { session: session });
-  }).
-  then(() =&gt; Event.aggregate([
-    {
-      $group: {
-        _id: {
-          month: { $month: <span class="hljs-string">'$createdAt'</span> },
-          year: { $year: <span class="hljs-string">'$createdAt'</span> }
-        },
-        count: { $sum: <span class="hljs-number">1</span> }
-      }
-    },
-    { $sort: { count: <span class="hljs-number">-1</span>, <span class="hljs-string">'_id.year'</span>: <span class="hljs-number">-1</span>, <span class="hljs-string">'_id.month'</span>: <span class="hljs-number">-1</span> } }
-  ]).session(session)).
-  then(res =&gt; {
-    assert.deepEqual(res, [
-      { _id: { month: <span class="hljs-number">6</span>, year: <span class="hljs-number">2018</span> }, count: <span class="hljs-number">2</span> },
-      { _id: { month: <span class="hljs-number">6</span>, year: <span class="hljs-number">2017</span> }, count: <span class="hljs-number">1</span> },
-      { _id: { month: <span class="hljs-number">5</span>, year: <span class="hljs-number">2017</span> }, count: <span class="hljs-number">1</span> }
-    ]);
-    session.commitTransaction();
-  });</code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/custom-casting.html b/docs/tutorials/custom-casting.html
deleted file mode 100644
index 627dfd87cf3..00000000000
--- a/docs/tutorials/custom-casting.html
+++ /dev/null
@@ -1,102 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: Custom Casting</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="custom-casting">Custom Casting</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p><a href="https://github.com/Automattic/mongoose/blob/master/History.md#540--2018-12-14">Mongoose 5.4.0</a> introduced <a href="http://thecodebarbarian.com/whats-new-in-mongoose-54-global-schematype-configuration">several ways to configure SchemaTypes globally</a>. One of these new features is the <a href="https://mongoosejs.com/docs/api.html#schematype_SchemaType-cast"><code>SchemaType.cast()</code> function</a>, which enables you to override Mongoose&#39;s built-in casting.</p>
-<p>For example, by default Mongoose will throw an error if you attempt to cast
-a string that contains a Japanese numeral to a number.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  age: <span class="hljs-built_in">Number</span>
-});
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({ age: <span class="hljs-string">'二'</span> });
-<span class="hljs-keyword">const</span> err = doc.validateSync();
-<span class="hljs-comment">// "Cast to Number failed for value "二" at path "age""</span>
-err.message;</code></pre>
-<p>You can overwrite the default casting function for numbers to allow converting
-the string that contains the Japanese numeral &quot;2&quot; to a number as shown below.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Calling `cast()` on a class that inherits from `SchemaType` returns the</span>
-<span class="hljs-comment">// current casting function.</span>
-<span class="hljs-keyword">const</span> originalCast = mongoose.Number.cast();
-
-<span class="hljs-comment">// Calling `cast()` with a function sets the current function used to</span>
-<span class="hljs-comment">// cast a given schema type, in this cast Numbers.</span>
-mongoose.Number.cast(v =&gt; {
-  <span class="hljs-keyword">if</span> (v === <span class="hljs-string">'二'</span>) {
-    <span class="hljs-keyword">return</span> <span class="hljs-number">2</span>;
-  }
-  <span class="hljs-keyword">return</span> originalCast(v);
-});
-
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  age: <span class="hljs-built_in">Number</span>
-});
-
-<span class="hljs-keyword">const</span> Model = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Model({ age: <span class="hljs-string">'二'</span> });
-<span class="hljs-keyword">const</span> err = doc.validateSync();
-err; <span class="hljs-comment">// null</span>
-doc.age; <span class="hljs-comment">// 2</span></code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/dates.html b/docs/tutorials/dates.html
deleted file mode 100644
index fe8cb0f9a77..00000000000
--- a/docs/tutorials/dates.html
+++ /dev/null
@@ -1,159 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: Working With Dates</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="working-with-dates">Working With Dates</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Here&#39;s how you declare a path of type <code>Date</code> with a Mongoose schema:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-
-<span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  <span class="hljs-comment">// `lastActiveAt` is a date</span>
-  lastActiveAt: <span class="hljs-built_in">Date</span>
-});
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);</code></pre>
-<p>When you create a user <a href="/docs/documents.html">document</a>, Mongoose will cast
-the value to a <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date">native JavaScript date</a>
-using the <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#Syntax"><code>Date()</code> constructor</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User({
-  name: <span class="hljs-string">'Jean-Luc Picard'</span>,
-  lastActiveAt: <span class="hljs-string">'2002-12-09'</span>
-});
-user.lastActiveAt <span class="hljs-keyword">instanceof</span> <span class="hljs-built_in">Date</span>; <span class="hljs-comment">// true</span></code></pre>
-<p>An invalid date will lead to a <code>CastError</code> when you <a href="/docs/validation.html">validate the document</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User({
-  name: <span class="hljs-string">'Jean-Luc Picard'</span>,
-  lastActiveAt: <span class="hljs-string">'not a date'</span>
-});
-user.lastActiveAt <span class="hljs-keyword">instanceof</span> <span class="hljs-built_in">Date</span>; <span class="hljs-comment">// false</span>
-user.validateSync().errors[<span class="hljs-string">'lastActiveAt'</span>]; <span class="hljs-comment">// CastError</span></code></pre>
-<h2 id="validators">Validators</h2>
-<p>Dates have two built-in validators: <code>min</code> and <code>max</code>. These validators will
-report a <code>ValidatorError</code> if the given date is strictly less than <code>min</code> or
-strictly greater than <code>max</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> episodeSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  title: <span class="hljs-built_in">String</span>,
-  airedAt: {
-    type: <span class="hljs-built_in">Date</span>,
-    <span class="hljs-comment">// The dates of the first and last episodes of</span>
-    <span class="hljs-comment">// Star Trek: The Next Generation</span>
-    min: <span class="hljs-string">'1987-09-28'</span>,
-    max: <span class="hljs-string">'1994-05-23'</span>
-  }
-});
-<span class="hljs-keyword">const</span> Episode = mongoose.model(<span class="hljs-string">'Episode'</span>, episodeSchema);
-
-<span class="hljs-keyword">const</span> ok = <span class="hljs-keyword">new</span> Episode({
-  title: <span class="hljs-string">'Encounter at Farpoint'</span>,
-  airedAt: <span class="hljs-string">'1987-09-28'</span>
-});
-ok.validateSync(); <span class="hljs-comment">// No error</span>
-
-<span class="hljs-keyword">const</span> bad = <span class="hljs-keyword">new</span> Episode({
-  title: <span class="hljs-string">'What You Leave Behind'</span>,
-  airedAt: <span class="hljs-string">'1999-06-02'</span>
-});
-bad.airedAt; <span class="hljs-comment">// "1999-06-02T00:00:00.000Z"</span>
-
-<span class="hljs-comment">// Path `airedAt` (Tue Jun 01 1999 20:00:00 GMT-0400 (EDT)) is after</span>
-<span class="hljs-comment">// maximum allowed value (Sun May 22 1994 20:00:00 GMT-0400 (EDT)).</span>
-bad.validateSync();</code></pre>
-<h2 id="querying">Querying</h2>
-<p>MongoDB supports querying by date ranges and sorting by dates. Here&#39;s some
-examples of querying by dates, date ranges, and sorting by date:</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Find episodes that aired on this exact date</span>
-<span class="hljs-keyword">return</span> Episode.find({ airedAt: <span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'1987-10-26'</span>) }).
-  then(episodes =&gt; {
-    episodes[<span class="hljs-number">0</span>].title; <span class="hljs-comment">// "Where No One Has Gone Before"</span>
-    <span class="hljs-comment">// Find episodes within a range of dates, sorted by date ascending</span>
-    <span class="hljs-keyword">return</span> Episode.
-      find({ airedAt: { $gte: <span class="hljs-string">'1987-10-19'</span>, $lte: <span class="hljs-string">'1987-10-26'</span> } }).
-      sort({ airedAt: <span class="hljs-number">1</span> });
-  }).
-  then(episodes =&gt; {
-    episodes[<span class="hljs-number">0</span>].title; <span class="hljs-comment">// "The Last Outpost"</span>
-    episodes[<span class="hljs-number">1</span>].title; <span class="hljs-comment">// "Where No One Has Gone Before"</span>
-  });</code></pre>
-<h2 id="casting-edge-cases">Casting Edge Cases</h2>
-<p>Date casting has a couple small cases where it differs from JavaScript&#39;s 
-native date parsing. First, Mongoose looks for a <a href="https://www.w3schools.com/jsref/jsref_valueof_string.asp"><code>valueOf()</code> function</a> on the given object,
-and calls <code>valueOf()</code> before casting the date. This means Mongoose can cast
-<a href="http://npmjs.com/package/moment">moment objects</a> to dates automatically.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> moment = <span class="hljs-built_in">require</span>(<span class="hljs-string">'moment'</span>);
-<span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User({
-  name: <span class="hljs-string">'Jean-Luc Picard'</span>,
-  lastActiveAt: moment.utc(<span class="hljs-string">'2002-12-09'</span>)
-});
-user.lastActiveAt; <span class="hljs-comment">// "2002-12-09T00:00:00.000Z"</span></code></pre>
-<p>By default, if you pass a numeric
-string to the Date constructor, JavaScript will attempt to convert it to a
-year.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-number">1552261496289</span>); <span class="hljs-comment">// "2019-03-10T23:44:56.289Z"</span>
-<span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'1552261496289'</span>); <span class="hljs-comment">// "Invalid Date"</span>
-<span class="hljs-keyword">new</span> <span class="hljs-built_in">Date</span>(<span class="hljs-string">'2010'</span>); <span class="hljs-comment">// 2010-01-01T00:00:00.000Z</span></code></pre>
-<p>Mongoose converts numeric strings that contain numbers outside the <a href="https://stackoverflow.com/questions/11526504/minimum-and-maximum-date">range of representable dates in JavaScript</a> and converts them to numbers before passing them to the date constructor.</p>
-<pre><code class="language-javascript"><span class="hljs-built_in">require</span>: <span class="hljs-built_in">Date</span> Tutorial.*Example <span class="hljs-number">1.4</span><span class="hljs-number">.3</span>]</code></pre>
-<h2 id="timezones">Timezones</h2>
-<p><a href="http://bsonspec.org/spec.html">MongoDB stores dates as 64-bit integers</a>, which
-means that Mongoose does <strong>not</strong> store timezone information by default. When
-you call <code>Date#toString()</code>, the JavaScript runtime will use <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTimezoneOffset">your OS&#39; timezone</a>.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/findoneandupdate.html b/docs/tutorials/findoneandupdate.html
deleted file mode 100644
index 12804c5d9d0..00000000000
--- a/docs/tutorials/findoneandupdate.html
+++ /dev/null
@@ -1,136 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: How to Use `findOneAndUpdate()` in Mongoose</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="how-to-use-findoneandupdate-in-mongoose">How to Use <code>findOneAndUpdate()</code> in Mongoose</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>The <a href="/docs/api.html#query_Query-findOneAndUpdate"><code>findOneAndUpdate()</code> function in Mongoose</a> has a wide variety of use cases. <a href="https://masteringjs.io/tutorials/mongoose/update">You should use <code>save()</code> to update documents where possible</a>, but there are some cases where you need to use <code>findOneAndUpdate()</code>. In this tutorial, you&#39;ll see how to use <code>findOneAndUpdate()</code>, and learn when you need to use it.</p>
-<ul>
-<li><a href="#getting-started">Getting Started</a></li>
-<li><a href="#atomic-updates">Atomic Updates</a></li>
-<li><a href="#upsert">Upsert</a></li>
-</ul>
-<h2 id="getting-started">Getting Started</h2>
-
-<p>As the name implies, <code>findOneAndUpdate()</code> finds the first document that matches a given <code>filter</code>, applies an <code>update</code>, and returns the document. By default, <code>findOneAndUpdate()</code> returns the document as it was <strong>before</strong> <code>update</code> was applied.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> Character = mongoose.model(<span class="hljs-string">'Character'</span>, <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  age: <span class="hljs-built_in">Number</span>
-}));
-
-<span class="hljs-keyword">await</span> Character.create({ name: <span class="hljs-string">'Jean-Luc Picard'</span> });
-
-<span class="hljs-keyword">const</span> filter = { name: <span class="hljs-string">'Jean-Luc Picard'</span> };
-<span class="hljs-keyword">const</span> update = { age: <span class="hljs-number">59</span> };
-
-<span class="hljs-comment">// `doc` is the document _before_ `update` was applied</span>
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Character.findOneAndUpdate(filter, update);
-doc.name; <span class="hljs-comment">// 'Jean-Luc Picard'</span>
-doc.age; <span class="hljs-comment">// undefined</span>
-
-doc = <span class="hljs-keyword">await</span> Character.findOne(filter);
-doc.age; <span class="hljs-comment">// 59</span></code></pre>
-<p>You should set the <code>new</code> option to <code>true</code> to return the document <strong>after</strong> <code>update</code> was applied.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> filter = { name: <span class="hljs-string">'Jean-Luc Picard'</span> };
-<span class="hljs-keyword">const</span> update = { age: <span class="hljs-number">59</span> };
-
-<span class="hljs-comment">// `doc` is the document _after_ `update` was applied because of</span>
-<span class="hljs-comment">// `new: true`</span>
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Character.findOneAndUpdate(filter, update, {
-  <span class="hljs-keyword">new</span>: <span class="hljs-literal">true</span>
-});
-doc.name; <span class="hljs-comment">// 'Jean-Luc Picard'</span>
-doc.age; <span class="hljs-comment">// 59</span></code></pre>
-<p>Mongoose&#39;s <code>findOneAndUpdate()</code> is slightly different from <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#findOneAndUpdate">the MongoDB Node.js driver&#39;s <code>findOneAndUpdate()</code></a> because it returns the document itself, not a <a href="http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~findAndModifyWriteOpResult">result object</a>.</p>
-<h2 id="atomic-updates">Atomic Updates</h2>
-
-<p>With the exception of an <a href="https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/#upsert-and-unique-index">unindexed upsert</a>, <a href="https://docs.mongodb.com/manual/core/write-operations-atomicity/#atomicity"><code>findOneAndUpdate()</code> is atomic</a>. That means you can assume the document doesn&#39;t change between when MongoDB finds the document and when it updates the document, <em>unless</em> you&#39;re doing an <a href="#upsert">upsert</a>.</p>
-<p>For example, if you&#39;re using <code>save()</code> to update a document, the document can change in MongoDB in between when you load the document using <code>findOne()</code> and when you save the document using <code>save()</code> as show below. For many use cases, the <code>save()</code> race condition is a non-issue. But you can work around it with <code>findOneAndUpdate()</code> (or <a href="/docs/transactions.html">transactions</a>) if you need to.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> filter = { name: <span class="hljs-string">'Jean-Luc Picard'</span> };
-<span class="hljs-keyword">const</span> update = { age: <span class="hljs-number">59</span> };
-
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Character.findOne({ name: <span class="hljs-string">'Jean-Luc Picard'</span> });
-
-<span class="hljs-comment">// Document changed in MongoDB, but not in Mongoose</span>
-<span class="hljs-keyword">await</span> Character.updateOne(filter, { name: <span class="hljs-string">'Will Riker'</span> });
-
-<span class="hljs-comment">// This will update `doc` age to `59`, even though the doc changed.</span>
-doc.age = <span class="hljs-number">59</span>;
-<span class="hljs-keyword">await</span> doc.save();
-
-doc = <span class="hljs-keyword">await</span> Character.findOne();
-doc.name; <span class="hljs-comment">// Will Riker</span>
-doc.age; <span class="hljs-comment">// 59</span></code></pre>
-<h2 id="upsert">Upsert</h2>
-
-<p>Using the <code>upsert</code> option, you can use <code>findOneAndUpdate()</code> as a find-and-<a href="https://docs.mongodb.com/manual/reference/method/db.collection.update/#db.collection.update">upsert</a> operation. An upsert behaves like a normal <code>findOneAndUpdate()</code> if it finds a document that matches <code>filter</code>. But, if no document matches <code>filter</code>, MongoDB will insert one by combining <code>filter</code> and <code>update</code> as shown below.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> filter = { name: <span class="hljs-string">'Will Riker'</span> };
-<span class="hljs-keyword">const</span> update = { age: <span class="hljs-number">29</span> };
-
-<span class="hljs-keyword">await</span> Character.countDocuments(filter); <span class="hljs-comment">// 0</span>
-
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> Character.findOneAndUpdate(filter, update, {
-  <span class="hljs-keyword">new</span>: <span class="hljs-literal">true</span>,
-  upsert: <span class="hljs-literal">true</span> <span class="hljs-comment">// Make this update into an upsert</span>
-});
-doc.name; <span class="hljs-comment">// Will Riker</span>
-doc.age; <span class="hljs-comment">// 29</span></code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/getters-setters.html b/docs/tutorials/getters-setters.html
deleted file mode 100644
index 09ed59c79f5..00000000000
--- a/docs/tutorials/getters-setters.html
+++ /dev/null
@@ -1,181 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: Getters/Setters in Mongoose</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="getterssetters-in-mongoose">Getters/Setters in Mongoose</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>Mongoose getters and setters allow you to execute custom logic when getting or setting a property on a <a href="/docs/documents.html">Mongoose document</a>. Getters let you transform data in MongoDB into a more user friendly form, and setters let you transform user data before it gets to MongoDB.</p>
-<h2 id="getters">Getters</h2>
-<p>Suppose you have a <code>User</code> collection and you want to obfuscate user emails to protect your users&#39; privacy. Below is a basic <code>userSchema</code> that obfuscates the user&#39;s email address.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  email: {
-    type: <span class="hljs-built_in">String</span>,
-    get: obfuscate
-  }
-});
-
-<span class="hljs-comment">// Mongoose passes the raw value in MongoDB `email` to the getter</span>
-<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">obfuscate</span>(<span class="hljs-params">email</span>) </span>{
-  <span class="hljs-keyword">const</span> separatorIndex = email.indexOf(<span class="hljs-string">'@'</span>);
-  <span class="hljs-keyword">if</span> (separatorIndex &lt; <span class="hljs-number">3</span>) {
-    <span class="hljs-comment">// 'ab@gmail.com' -&gt; '**@gmail.com'</span>
-    <span class="hljs-keyword">return</span> email.slice(<span class="hljs-number">0</span>, separatorIndex).replace(<span class="hljs-regexp">/./g</span>, <span class="hljs-string">'*'</span>) +
-      email.slice(separatorIndex);
-  }
-  <span class="hljs-comment">// 'test42@gmail.com' -&gt; 'te****@gmail.com'</span>
-  <span class="hljs-keyword">return</span> email.slice(<span class="hljs-number">0</span>, <span class="hljs-number">2</span>) +
-    email.slice(<span class="hljs-number">2</span>, separatorIndex).replace(<span class="hljs-regexp">/./g</span>, <span class="hljs-string">'*'</span>) +
-    email.slice(separatorIndex);
-}
-
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-<span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User({ email: <span class="hljs-string">'ab@gmail.com'</span> });
-user.email; <span class="hljs-comment">// **@gmail.com</span></code></pre>
-<p>Keep in mind that getters do <strong>not</strong> impact the underlying data stored in
-MongoDB. If you save <code>user</code>, the <code>email</code> property will be &#39;ab@gmail.com&#39; in
-the database.</p>
-<p>By default, Mongoose executes getters when converting a document to JSON,
-including <a href="http://expressjs.com/en/4x/api.html#res.json">Express&#39; <code>res.json()</code> function</a>.</p>
-<pre><code class="language-javascript">app.get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">req, res</span>) </span>{
-  <span class="hljs-keyword">return</span> User.findOne().
-    <span class="hljs-comment">// The `email` getter will run here</span>
-    then(doc =&gt; res.json(doc)).
-    <span class="hljs-keyword">catch</span>(err =&gt; res.status(<span class="hljs-number">500</span>).json({ message: err.message }));
-});</code></pre>
-<p>To disable running getters when converting a document to JSON, set the <a href="https://mongoosejs.com/docs/guide.html#toJSON"><code>toJSON.getters</code> option to <code>false</code> in your schema</a> as shown below.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  email: {
-    type: <span class="hljs-built_in">String</span>,
-    get: obfuscate
-  }
-}, { toJSON: { getters: <span class="hljs-literal">false</span> } });</code></pre>
-<p>To skip getters on a one-off basis, use <a href="/docs/api/document.html#document_Document-get"><code>user.get()</code> with the <code>getters</code> option set to <code>false</code></a> as shown below.</p>
-<pre><code class="language-javascript">user.get(<span class="hljs-string">'email'</span>, <span class="hljs-literal">null</span>, { getters: <span class="hljs-literal">false</span> }); <span class="hljs-comment">// 'ab@gmail.com'</span></code></pre>
-<h2 id="setters">Setters</h2>
-<p>Suppose you want to make sure all user emails in your database are lowercased to 
-make it easy to search without worrying about case. Below is an example
-<code>userSchema</code> that ensures emails are lowercased.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  email: {
-    type: <span class="hljs-built_in">String</span>,
-    set: v =&gt; v.toLowerCase()
-  }
-});
-
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User({ email: <span class="hljs-string">'TEST@gmail.com'</span> });
-user.email; <span class="hljs-comment">// 'test@gmail.com'</span>
-
-<span class="hljs-comment">// The raw value of `email` is lowercased</span>
-user.get(<span class="hljs-string">'email'</span>, <span class="hljs-literal">null</span>, { getters: <span class="hljs-literal">false</span> }); <span class="hljs-comment">// 'test@gmail.com'</span>
-
-user.set({ email: <span class="hljs-string">'NEW@gmail.com'</span> });
-user.email; <span class="hljs-comment">// 'new@gmail.com'</span></code></pre>
-<p>Mongoose also runs setters on update operations, like <a href="/docs/api/query.html#query_Query-updateOne"><code>updateOne()</code></a>. Mongoose will
-<a href="https://masteringjs.io/tutorials/mongoose/upsert">upsert a document</a> with a
-lowercased <code>email</code> in the below example.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">await</span> User.updateOne({}, { email: <span class="hljs-string">'TEST@gmail.com'</span> }, { upsert: <span class="hljs-literal">true</span> });
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> User.findOne();
-doc.email; <span class="hljs-comment">// 'test@gmail.com'</span></code></pre>
-<p>In a setter function, <code>this</code> can be either the document being set or the query
-being run. If you don&#39;t want your setter to run when you call <code>updateOne()</code>,
-you add an if statement that checks if <code>this</code> is a Mongoose document as shown
-below.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  email: {
-    type: <span class="hljs-built_in">String</span>,
-    set: toLower
-  }
-});
-
-<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">toLower</span>(<span class="hljs-params">email</span>) </span>{
-  <span class="hljs-comment">// Don't transform `email` if using `updateOne()` or `updateMany()`</span>
-  <span class="hljs-keyword">if</span> (!(<span class="hljs-keyword">this</span> <span class="hljs-keyword">instanceof</span> mongoose.Document)) {
-    <span class="hljs-keyword">return</span> email;
-  }
-  <span class="hljs-keyword">return</span> email.toLowerCase();
-}
-
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-<span class="hljs-keyword">await</span> User.updateOne({}, { email: <span class="hljs-string">'TEST@gmail.com'</span> }, { upsert: <span class="hljs-literal">true</span> });
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> User.findOne();
-doc.email; <span class="hljs-comment">// 'TEST@gmail.com'</span></code></pre>
-<h2 id="differences-vs-es6-getterssetters">Differences vs ES6 Getters/Setters</h2>
-<p>Mongoose setters are different from <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set">ES6 setters</a> because they allow you to transform the value being set. With ES6 setters, you
-would need to store an internal <code>_email</code> property to use a setter. With Mongoose,
-you do <strong>not</strong> need to define an internal <code>_email</code> property or define a 
-corresponding getter for <code>email</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-class"><span class="hljs-keyword">class</span> <span class="hljs-title">User</span> </span>{
-  <span class="hljs-comment">// This won't convert the email to lowercase! That's because `email`</span>
-  <span class="hljs-comment">// is just a setter, the actual `email` property doesn't store any data.</span>
-  set email(v) {
-    <span class="hljs-keyword">return</span> v.toLowerCase();
-  }
-}
-
-<span class="hljs-keyword">const</span> user = <span class="hljs-keyword">new</span> User();
-user.email = <span class="hljs-string">'TEST@gmail.com'</span>;
-
-user.email; <span class="hljs-comment">// undefined</span></code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/lean.html b/docs/tutorials/lean.html
deleted file mode 100644
index 8e349b60e9e..00000000000
--- a/docs/tutorials/lean.html
+++ /dev/null
@@ -1,261 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: Faster Mongoose Queries With Lean</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="faster-mongoose-queries-with-lean">Faster Mongoose Queries With Lean</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>The <a href="/docs/api.html#query_Query-lean">lean option</a> tells Mongoose to skip
-<a href="/docs/api.html#model_Model.hydrate">hydrating</a> the result documents. This
-makes queries faster and less memory intensive, but the result documents are
-plain old JavaScript objects (POJOs), <strong>not</strong> <a href="/docs/documents.html">Mongoose documents</a>.
-In this tutorial, you&#39;ll learn more about the tradeoffs of using <code>lean()</code>.</p>
-<ul>
-<li><a href="#using-lean">Using Lean</a></li>
-<li><a href="#lean-and-populate">Lean and Populate</a></li>
-<li><a href="#when-to-use-lean">When to Use Lean</a></li>
-</ul>
-<h2 id="using-lean"><a href="#using-lean">Using Lean</a></h2>
-
-<p>By default, Mongoose queries return an instance of the
-<a href="/docs/api.html#Document">Mongoose <code>Document</code> class</a>. Documents are much
-heavier than vanilla JavaScript objects, because they have a lot of internal
-state for change tracking. Enabling the <code>lean</code> option tells Mongoose to skip
-instantiating a full Mongoose document and just give you the POJO.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> leanDoc = <span class="hljs-keyword">await</span> MyModel.findOne().lean();</code></pre>
-<p>How much smaller are lean documents? Here&#39;s a comparison.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> MyModel = mongoose.model(<span class="hljs-string">'Test'</span>, schema);
-
-<span class="hljs-keyword">await</span> MyModel.create({ name: <span class="hljs-string">'test'</span> });
-
-<span class="hljs-comment">// Module that estimates the size of an object in memory</span>
-<span class="hljs-keyword">const</span> sizeof = <span class="hljs-built_in">require</span>(<span class="hljs-string">'object-sizeof'</span>);
-
-<span class="hljs-keyword">const</span> normalDoc = <span class="hljs-keyword">await</span> MyModel.findOne();
-<span class="hljs-comment">// To enable the `lean` option for a query, use the `lean()` function.</span>
-<span class="hljs-keyword">const</span> leanDoc = <span class="hljs-keyword">await</span> MyModel.findOne().lean();
-
-sizeof(normalDoc); <span class="hljs-comment">// &gt;= 1000</span>
-sizeof(leanDoc); <span class="hljs-comment">// 86, 10x smaller!</span>
-
-<span class="hljs-comment">// In case you were wondering, the JSON form of a Mongoose doc is the same</span>
-<span class="hljs-comment">// as the POJO. This additional memory only affects how much memory your</span>
-<span class="hljs-comment">// Node.js process uses, not how much data is sent over the network.</span>
-<span class="hljs-built_in">JSON</span>.stringify(normalDoc).length === <span class="hljs-built_in">JSON</span>.stringify(leanDoc.length); <span class="hljs-comment">// true</span></code></pre>
-<p>Under the hood, after executing a query, Mongoose converts the query results
-from POJOs to Mongoose documents. If you turn on the <code>lean</code> option, Mongoose
-skips this step.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> normalDoc = <span class="hljs-keyword">await</span> MyModel.findOne();
-<span class="hljs-keyword">const</span> leanDoc = <span class="hljs-keyword">await</span> MyModel.findOne().lean();
-
-normalDoc <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// true</span>
-normalDoc.constructor.name; <span class="hljs-comment">// 'model'</span>
-
-leanDoc <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span>
-leanDoc.constructor.name; <span class="hljs-comment">// 'Object'</span></code></pre>
-<p>The downside of enabling <code>lean</code> is that lean docs don&#39;t have:</p>
-<ul>
-<li>Change tracking</li>
-<li>Casting and validation</li>
-<li>Getters and setters</li>
-<li>Virtuals</li>
-<li><code>save()</code></li>
-</ul>
-<p>For example, the following code sample shows that the <code>Person</code> model&#39;s getters
-and virtuals don&#39;t run if you enable <code>lean</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Define a `Person` model. Schema has 2 custom getters and a `fullName`</span>
-<span class="hljs-comment">// virtual. Neither the getters nor the virtuals will run if lean is enabled.</span>
-<span class="hljs-keyword">const</span> personSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  firstName: {
-    type: <span class="hljs-built_in">String</span>,
-    get: capitalizeFirstLetter
-  },
-  lastName: {
-    type: <span class="hljs-built_in">String</span>,
-    get: capitalizeFirstLetter
-  }
-});
-personSchema.virtual(<span class="hljs-string">'fullName'</span>).get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-string">`<span class="hljs-subst">${this.firstName}</span> <span class="hljs-subst">${this.lastName}</span>`</span>;
-});
-<span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">capitalizeFirstLetter</span>(<span class="hljs-params">v</span>) </span>{
-  <span class="hljs-comment">// Convert 'bob' -&gt; 'Bob'</span>
-  <span class="hljs-keyword">return</span> v.charAt(<span class="hljs-number">0</span>).toUpperCase() + v.substr(<span class="hljs-number">1</span>);
-}
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, personSchema);
-
-<span class="hljs-comment">// Create a doc and load it as a lean doc</span>
-<span class="hljs-keyword">await</span> Person.create({ firstName: <span class="hljs-string">'benjamin'</span>, lastName: <span class="hljs-string">'sisko'</span> });
-<span class="hljs-keyword">const</span> normalDoc = <span class="hljs-keyword">await</span> Person.findOne();
-<span class="hljs-keyword">const</span> leanDoc = <span class="hljs-keyword">await</span> Person.findOne().lean();
-
-normalDoc.fullName; <span class="hljs-comment">// 'Benjamin Sisko'</span>
-normalDoc.firstName; <span class="hljs-comment">// 'Benjamin', because of `capitalizeFirstLetter()`</span>
-normalDoc.lastName; <span class="hljs-comment">// 'Sisko', because of `capitalizeFirstLetter()`</span>
-
-leanDoc.fullName; <span class="hljs-comment">// undefined</span>
-leanDoc.firstName; <span class="hljs-comment">// 'benjamin', custom getter doesn't run</span>
-leanDoc.lastName; <span class="hljs-comment">// 'sisko', custom getter doesn't run</span></code></pre>
-<h2 id="lean-and-populate"><a href="#lean-and-populate">Lean and Populate</a></h2>
-
-<p><a href="/docs/populate.html">Populate</a> works with <code>lean()</code>. If you
-use both <code>populate()</code> and <code>lean()</code>, the <code>lean</code> option propagates to the
-populated documents as well. In the below example, both the top-level
-&#39;Group&#39; documents and the populated &#39;Person&#39; documents will be lean.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Create models</span>
-<span class="hljs-keyword">const</span> Group = mongoose.model(<span class="hljs-string">'Group'</span>, <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  members: [{ type: mongoose.ObjectId, ref: <span class="hljs-string">'Person'</span> }]
-}));
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>
-}));
-
-<span class="hljs-comment">// Initialize data</span>
-<span class="hljs-keyword">const</span> people = <span class="hljs-keyword">await</span> Person.create([
-  { name: <span class="hljs-string">'Benjamin Sisko'</span> },
-  { name: <span class="hljs-string">'Kira Nerys'</span> }
-]);
-<span class="hljs-keyword">await</span> Group.create({
-  name: <span class="hljs-string">'Star Trek: Deep Space Nine Characters'</span>,
-  members: people.map(p =&gt; p._id)
-});
-
-<span class="hljs-comment">// Execute a lean query</span>
-<span class="hljs-keyword">const</span> group = <span class="hljs-keyword">await</span> Group.findOne().lean().populate(<span class="hljs-string">'members'</span>);
-group.members[<span class="hljs-number">0</span>].name; <span class="hljs-comment">// 'Benjamin Sisko'</span>
-group.members[<span class="hljs-number">1</span>].name; <span class="hljs-comment">// 'Kira Nerys'</span>
-
-<span class="hljs-comment">// Both the `group` and the populated `members` are lean.</span>
-group <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span>
-group.members[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span>
-group.members[<span class="hljs-number">1</span>] <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span></code></pre>
-<p><a href="/docs/populate.html#populate-virtuals">Virtual populate</a> also works with lean.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Create models</span>
-<span class="hljs-keyword">const</span> groupSchema = <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-built_in">String</span> });
-groupSchema.virtual(<span class="hljs-string">'members'</span>, {
-  ref: <span class="hljs-string">'Person'</span>,
-  localField: <span class="hljs-string">'_id'</span>,
-  foreignField: <span class="hljs-string">'groupId'</span>
-});
-<span class="hljs-keyword">const</span> Group = mongoose.model(<span class="hljs-string">'Group'</span>, groupSchema);
-<span class="hljs-keyword">const</span> Person = mongoose.model(<span class="hljs-string">'Person'</span>, <span class="hljs-keyword">new</span> mongoose.Schema({
-  name: <span class="hljs-built_in">String</span>,
-  groupId: mongoose.ObjectId
-}));
-
-<span class="hljs-comment">// Initialize data</span>
-<span class="hljs-keyword">const</span> g = <span class="hljs-keyword">await</span> Group.create({ name: <span class="hljs-string">'DS9 Characters'</span> });
-<span class="hljs-keyword">const</span> people = <span class="hljs-keyword">await</span> Person.create([
-  { name: <span class="hljs-string">'Benjamin Sisko'</span>, groupId: g._id },
-  { name: <span class="hljs-string">'Kira Nerys'</span>, groupId: g._id }
-]);
-
-<span class="hljs-comment">// Execute a lean query</span>
-<span class="hljs-keyword">const</span> group = <span class="hljs-keyword">await</span> Group.findOne().lean().populate({
-  path: <span class="hljs-string">'members'</span>,
-  options: { sort: { name: <span class="hljs-number">1</span> } }
-});
-group.members[<span class="hljs-number">0</span>].name; <span class="hljs-comment">// 'Benjamin Sisko'</span>
-group.members[<span class="hljs-number">1</span>].name; <span class="hljs-comment">// 'Kira Nerys'</span>
-
-<span class="hljs-comment">// Both the `group` and the populated `members` are lean.</span>
-group <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span>
-group.members[<span class="hljs-number">0</span>] <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span>
-group.members[<span class="hljs-number">1</span>] <span class="hljs-keyword">instanceof</span> mongoose.Document; <span class="hljs-comment">// false</span></code></pre>
-<h2 id="when-to-use-lean"><a href="#when-to-use-lean">When to Use Lean</a></h2>
-
-<p>If you&#39;re executing a query and sending the results without modification to,
-say, an <a href="http://expressjs.com/en/4x/api.html#res">Express response</a>, you should
-use lean. In general, if you do not modify the query results and do not use
-<a href="/docs/api.html#schematype_SchemaType-get">custom getters</a>, you should use
-<code>lean()</code>. If you modify the query results or rely on features like getters
-or <a href="/docs/api.html#document_Document-toObject">transforms</a>, you should not
-use <code>lean()</code>.</p>
-<p>Below is an example of an <a href="http://expressjs.com/en/guide/routing.html">Express route</a>
-that is a good candidate for <code>lean()</code>. This route does not modify the <code>person</code>
-doc and doesn&#39;t rely on any Mongoose-specific functionality.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// As long as you don't need any of the Person model's virtuals or getters,</span>
-<span class="hljs-comment">// you can use `lean()`.</span>
-app.get(<span class="hljs-string">'/person/:id'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">req, res</span>) </span>{
-  Person.findOne({ _id: req.params.id }).lean().
-    then(person =&gt; res.json({ person })).
-    <span class="hljs-keyword">catch</span>(error =&gt; res.json({ error: error.message }));
-});</code></pre>
-<p>Below is an example of an Express route that should <strong>not</strong> use <code>lean()</code>. As
-a general rule of thumb, <code>GET</code> routes are good candidates for <code>lean()</code> in a
-<a href="https://en.wikipedia.org/wiki/Representational_state_transfer">RESTful API</a>.
-On the other hand, <code>PUT</code>, <code>POST</code>, etc. routes generally should not use <code>lean()</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// This route should **not** use `lean()`, because lean means no `save()`.</span>
-app.put(<span class="hljs-string">'/person/:id'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">req, res</span>) </span>{
-  Person.findOne({ _id: req.params.id }).
-    then(person =&gt; {
-      assert.ok(person);
-      <span class="hljs-built_in">Object</span>.assign(person, req.body);
-      <span class="hljs-keyword">return</span> person.save();
-    }).
-    then(person =&gt; res.json({ person })).
-    <span class="hljs-keyword">catch</span>(error =&gt; res.json({ error: error.message }));
-});</code></pre>
-<p>Remember that virtuals do <strong>not</strong> end up in <code>lean()</code> query results. Use the
-<a href="http://plugins.mongoosejs.io/plugins/lean-virtuals">mongoose-lean-virtuals plugin</a>
-to add virtuals to your lean query results.</p>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/query_casting.html b/docs/tutorials/query_casting.html
deleted file mode 100644
index 1a7b068de14..00000000000
--- a/docs/tutorials/query_casting.html
+++ /dev/null
@@ -1,140 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: Query Casting</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="query-casting">Query Casting</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>The first parameter to <a href="https://mongoosejs.com/docs/api.html#model_Model.find"><code>Model.find()</code></a>, <a href="https://mongoosejs.com/docs/api.html#query_Query-find"><code>Query#find()</code></a>, <a href="https://mongoosejs.com/docs/api.html#model_Model.findOne"><code>Model.findOne()</code></a>, etc. is called <code>filter</code>. In older content this parameter is sometimes called <code>query</code> or <code>conditions</code>. For example:</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> query = Character.find({ name: <span class="hljs-string">'Jean-Luc Picard'</span> });
-query.getFilter(); <span class="hljs-comment">// `{ name: 'Jean-Luc Picard' }`</span>
-
-<span class="hljs-comment">// Subsequent chained calls merge new properties into the filter</span>
-query.find({ age: { $gt: <span class="hljs-number">50</span> } });
-query.getFilter(); <span class="hljs-comment">// `{ name: 'Jean-Luc Picard', age: { $gt: 50 } }`</span></code></pre>
-<p>When you execute the query using <a href="https://mongoosejs.com/docs/api.html#query_Query-exec"><code>Query#exec()</code></a> or <a href="https://mongoosejs.com/docs/api.html#query_Query-then"><code>Query#then()</code></a>, Mongoose <em>casts</em> the filter to match your schema.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Note that `_id` and `age` are strings. Mongoose will cast `_id` to</span>
-<span class="hljs-comment">// a MongoDB ObjectId and `age.$gt` to a number.</span>
-<span class="hljs-keyword">const</span> query = Character.findOne({
-  _id: <span class="hljs-string">'5cdc267dd56b5662b7b7cc0c'</span>,
-  age: { $gt: <span class="hljs-string">'50'</span> }
-});
-
-<span class="hljs-comment">// `{ _id: '5cdc267dd56b5662b7b7cc0c', age: { $gt: '50' } }`</span>
-<span class="hljs-comment">// Query hasn't been executed yet, so Mongoose hasn't casted the filter.</span>
-query.getFilter();
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> query.exec();
-doc.name; <span class="hljs-comment">// "Jean-Luc Picard"</span>
-
-<span class="hljs-comment">// Mongoose casted the filter, so `_id` became an ObjectId and `age.$gt`</span>
-<span class="hljs-comment">// became a number.</span>
-query.getFilter()._id <span class="hljs-keyword">instanceof</span> mongoose.Types.ObjectId; <span class="hljs-comment">// true</span>
-<span class="hljs-keyword">typeof</span> query.getFilter().age.$gt === <span class="hljs-string">'number'</span>; <span class="hljs-comment">// true</span></code></pre>
-<p>If Mongoose fails to cast the filter to your schema, your query will throw a <code>CastError</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> query = Character.findOne({ age: { $lt: <span class="hljs-string">'not a number'</span> } });
-
-<span class="hljs-keyword">const</span> err = <span class="hljs-keyword">await</span> query.exec().then(() =&gt; <span class="hljs-literal">null</span>, err =&gt; err);
-err <span class="hljs-keyword">instanceof</span> mongoose.CastError; <span class="hljs-comment">// true</span>
-<span class="hljs-comment">// Cast to number failed for value "not a number" at path "age" for</span>
-<span class="hljs-comment">// model "Character"</span>
-err.message;</code></pre>
-<h2 id="the-strictquery-option">The <code>strictQuery</code> Option</h2>
-<p>By default, Mongoose does <strong>not</strong> cast filter properties that aren&#39;t in your schema.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> query = Character.findOne({ notInSchema: { $lt: <span class="hljs-string">'not a number'</span> } });
-
-<span class="hljs-comment">// No error because `notInSchema` is not defined in the schema</span>
-<span class="hljs-keyword">await</span> query.exec();</code></pre>
-<p>You can configure this behavior using the <a href="https://mongoosejs.com/docs/guide.html#strictQuery"><code>strictQuery</code> option for schemas</a>. This option is analagous to the <a href="https://mongoosejs.com/docs/guide.html#strict"><code>strict</code> option</a>. Setting <code>strictQuery</code> to <code>true</code> removes non-schema properties from the filter:</p>
-<pre><code class="language-javascript">mongoose.deleteModel(<span class="hljs-string">'Character'</span>);
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-built_in">String</span>, age: <span class="hljs-built_in">Number</span> }, {
-  strictQuery: <span class="hljs-literal">true</span>
-});
-Character = mongoose.model(<span class="hljs-string">'Character'</span>, schema);
-
-<span class="hljs-keyword">const</span> query = Character.findOne({ notInSchema: { $lt: <span class="hljs-string">'not a number'</span> } });
-
-<span class="hljs-keyword">await</span> query.exec();
-query.getFilter(); <span class="hljs-comment">// Empty object `{}`, Mongoose removes `notInSchema`</span></code></pre>
-<p>To make Mongoose throw an error if your <code>filter</code> has a property that isn&#39;t in the schema, set <code>strictQuery</code> to <code>&#39;throw&#39;</code>:</p>
-<pre><code class="language-javascript">mongoose.deleteModel(<span class="hljs-string">'Character'</span>);
-<span class="hljs-keyword">const</span> schema = <span class="hljs-keyword">new</span> mongoose.Schema({ name: <span class="hljs-built_in">String</span>, age: <span class="hljs-built_in">Number</span> }, {
-  strictQuery: <span class="hljs-string">'throw'</span>
-});
-Character = mongoose.model(<span class="hljs-string">'Character'</span>, schema);
-
-<span class="hljs-keyword">const</span> query = Character.findOne({ notInSchema: { $lt: <span class="hljs-string">'not a number'</span> } });
-
-<span class="hljs-keyword">const</span> err = <span class="hljs-keyword">await</span> query.exec().then(() =&gt; <span class="hljs-literal">null</span>, err =&gt; err);
-err.name; <span class="hljs-comment">// 'StrictModeError'</span>
-<span class="hljs-comment">// Path "notInSchema" is not in schema and strictQuery is 'throw'.</span>
-err.message;</code></pre>
-<h2 id="implicit-in">Implicit <code>$in</code></h2>
-<p>Because of schemas, Mongoose knows what types fields should be, so it can provide some neat syntactic sugar. For example, if you forget to put <a href="https://docs.mongodb.com/manual/reference/operator/query/in/"><code>$in</code></a> on a non-array field, Mongoose will add <code>$in</code> for you.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Normally wouldn't find anything because `name` is a string, but</span>
-<span class="hljs-comment">// Mongoose automatically inserts `$in`</span>
-<span class="hljs-keyword">const</span> query = Character.findOne({ name: [<span class="hljs-string">'Jean-Luc Picard'</span>, <span class="hljs-string">'Will Riker'</span>] });
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> query.exec();
-doc.name; <span class="hljs-comment">// "Jean-Luc Picard"</span>
-
-<span class="hljs-comment">// `{ name: { $in: ['Jean-Luc Picard', 'Will Riker'] } }`</span>
-query.getFilter();</code></pre>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/tutorials/virtuals.html b/docs/tutorials/virtuals.html
deleted file mode 100644
index ab11f943631..00000000000
--- a/docs/tutorials/virtuals.html
+++ /dev/null
@@ -1,215 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.4-pre: Mongoose Tutorials: Virtuals</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"><link rel="stylesheet" href="/docs/css/inlinecpc.css"><script type="text/javascript" src="/docs/js/native.js"></script><style>p { line-height: 1.5em }
-</style></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.4-pre</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.19</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><h1 id="virtuals">Virtuals</h1>
-<script>
-  _native.init("CK7DT53U",{
-    targetClass: 'native-inline'
-  });
-</script>
-
-<div class="native-inline">
-  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-</div>
-
-<p>In Mongoose, a virtual is a property that is <strong>not</strong> stored in MongoDB. 
-Virtuals are typically used for computed properties on documents.</p>
-<ul>
-<li><a href="#your-first-virtual">Your First Virtual</a></li>
-<li><a href="#virtual-setters">Virtual Setters</a></li>
-<li><a href="#virtuals-in-json">Virtuals in JSON</a></li>
-<li><a href="#virtuals-with-lean">Virtuals with Lean</a></li>
-<li><a href="#limitations">Limitations</a></li>
-<li><a href="#populate">Populate</a></li>
-<li><a href="#further-reading">Further Reading</a></li>
-</ul>
-<h2 id="your-first-virtual">Your First Virtual</h2>
-<p>Suppose you have a <code>User</code> model. Every user has an <code>email</code>, but you also
-want the email&#39;s domain. For example, the domain portion of 
-&#39;test@gmail.com&#39; is &#39;gmail.com&#39;.</p>
-<p>Below is one way to implement the <code>domain</code> property using a virtual.
-You define virtuals on a schema using the <a href="/docs/api/schema.html#schema_Schema-virtual"><code>Schema#virtual()</code> function</a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = mongoose.Schema({
-  email: <span class="hljs-built_in">String</span>
-});
-<span class="hljs-comment">// Create a virtual property `domain` that's computed from `email`.</span>
-userSchema.virtual(<span class="hljs-string">'domain'</span>).get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.email.slice(<span class="hljs-keyword">this</span>.email.indexOf(<span class="hljs-string">'@'</span>) + <span class="hljs-number">1</span>);
-});
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">let</span> doc = <span class="hljs-keyword">await</span> User.create({ email: <span class="hljs-string">'test@gmail.com'</span> });
-<span class="hljs-comment">// `domain` is now a property on User documents.</span>
-doc.domain; <span class="hljs-comment">// 'gmail.com'</span></code></pre>
-<p>The <code>Schema#virtual()</code> function returns a <a href="/docs/api/virtualtype.html"><code>VirtualType</code> object</a>. Unlike normal document properties,
-virtuals do not have any underlying value and Mongoose does not do
-any type coercion on virtuals. However, virtuals do have
-<a href="/docs/tutorials/getters-setters.html">getters and setters</a>, which make 
-them ideal for computed properties, like the <code>domain</code> example above.</p>
-<h2 id="virtual-setters">Virtual Setters</h2>
-<p>You can also use virtuals to set multiple properties at once as an
-alternative to <a href="/docs/tutorials/getters-setters.html#setters">custom setters on normal properties</a>. For example, suppose
-you have two string properties: <code>firstName</code> and <code>lastName</code>. You can
-create a virtual property <code>fullName</code> that lets you set both of
-these properties at once. The key detail is that, in virtual getters and
-setters, <code>this</code> refers to the document the virtual is attached to.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = mongoose.Schema({
-  firstName: <span class="hljs-built_in">String</span>,
-  lastName: <span class="hljs-built_in">String</span>
-});
-<span class="hljs-comment">// Create a virtual property `fullName` with a getter and setter.</span>
-userSchema.virtual(<span class="hljs-string">'fullName'</span>).
-  get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{ <span class="hljs-keyword">return</span> <span class="hljs-string">`<span class="hljs-subst">${this.firstName}</span> <span class="hljs-subst">${this.lastName}</span>`</span>; }).
-  set(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-    <span class="hljs-comment">// `v` is the value being set, so use the value to set</span>
-    <span class="hljs-comment">// `firstName` and `lastName`.</span>
-    <span class="hljs-keyword">const</span> firstName = v.substring(<span class="hljs-number">0</span>, v.indexOf(<span class="hljs-string">' '</span>));
-    <span class="hljs-keyword">const</span> lastName = v.substring(v.indexOf(<span class="hljs-string">' '</span>) + <span class="hljs-number">1</span>);
-    <span class="hljs-keyword">this</span>.set({ firstName, lastName });
-  });
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> User();
-<span class="hljs-comment">// Vanilla JavaScript assignment triggers the setter</span>
-doc.fullName = <span class="hljs-string">'Jean-Luc Picard'</span>;
-
-doc.fullName; <span class="hljs-comment">// 'Jean-Luc Picard'</span>
-doc.firstName; <span class="hljs-comment">// 'Jean-Luc'</span>
-doc.lastName; <span class="hljs-comment">// 'Picard'</span></code></pre>
-<h2 id="virtuals-in-json">Virtuals in JSON</h2>
-<p>By default, Mongoose does not include virtuals when you convert a document to 
-JSON. For example, if you pass a document to <a href="http://expressjs.com/en/4x/api.html#res.json">Express&#39;  <code>res.json()</code> function</a>,
-virtuals will <strong>not</strong> be included by default.</p>
-<p>To include virtuals in <code>res.json()</code>, you need to set the
-<a href="/docs/guide.html#toJSON"><code>toJSON</code> schema option</a> to <code>{ virtuals: true }</code>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> opts = { toJSON: { virtuals: <span class="hljs-literal">true</span> } };
-<span class="hljs-keyword">const</span> userSchema = mongoose.Schema({
-  _id: <span class="hljs-built_in">Number</span>,
-  email: <span class="hljs-built_in">String</span>
-}, opts);
-<span class="hljs-comment">// Create a virtual property `domain` that's computed from `email`.</span>
-userSchema.virtual(<span class="hljs-string">'domain'</span>).get(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.email.slice(<span class="hljs-keyword">this</span>.email.indexOf(<span class="hljs-string">'@'</span>) + <span class="hljs-number">1</span>);
-});
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> User({ _id: <span class="hljs-number">1</span>, email: <span class="hljs-string">'test@gmail.com'</span> });
-
-doc.toJSON().domain; <span class="hljs-comment">// 'gmail.com'</span>
-<span class="hljs-comment">// {"_id":1,"email":"test@gmail.com","domain":"gmail.com","id":"1"}</span>
-<span class="hljs-built_in">JSON</span>.stringify(doc); 
-
-<span class="hljs-comment">// To skip applying virtuals, pass `virtuals: false` to `toJSON()`</span>
-doc.toJSON({ virtuals: <span class="hljs-literal">false</span> }).domain; <span class="hljs-comment">// undefined</span></code></pre>
-<h2 id="virtuals-with-lean">Virtuals with Lean</h2>
-<p>Virtuals are properties on Mongoose documents. If you use the
-<a href="/docs/tutorials/lean.html">lean option</a>, that means your queries return POJOs
-rather than full Mongoose documents. That means no virtuals if you use
-<a href="/docs/api/query.html#query_Query-lean"><code>lean()</code></a>.</p>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> fullDoc = <span class="hljs-keyword">await</span> User.findOne();
-fullDoc.domain; <span class="hljs-comment">// 'gmail.com'</span>
-
-<span class="hljs-keyword">const</span> leanDoc = <span class="hljs-keyword">await</span> User.findOne().lean();
-leanDoc.domain; <span class="hljs-comment">// undefined</span></code></pre>
-<p>If you use <code>lean()</code> for performance, but still need virtuals, Mongoose
-has an
-<a href="https://plugins.mongoosejs.io/plugins/lean-virtuals">officially supported <code>mongoose-lean-virtuals</code> plugin</a>
-that decorates lean documents with virtuals.</p>
-<h2 id="limitations">Limitations</h2>
-<p>Mongoose virtuals are <strong>not</strong> stored in MongoDB, which means you can&#39;t query
-based on Mongoose virtuals.</p>
-<pre><code class="language-javascript"><span class="hljs-comment">// Will **not** find any results, because `domain` is not stored in</span>
-<span class="hljs-comment">// MongoDB.</span>
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> User.findOne({ domain: <span class="hljs-string">'gmail.com'</span> });
-doc; <span class="hljs-comment">// undefined</span></code></pre>
-<p>If you want to query by a computed property, you should set the property using
-a <a href="/docs/tutorials/getters-setters.html">custom setter</a> or <a href="/docs/middleware.html">pre save middleware</a>.</p>
-<h2 id="populate">Populate</h2>
-<p>Mongoose also supports <a href="/docs/populate.html">populating virtuals</a>. A populated
-virtual contains documents from another collection. To define a populated
-virtual, you need to specify:</p>
-<ul>
-<li>The <code>ref</code> option, which tells Mongoose which model to populate documents from.</li>
-<li>The <code>localField</code> and <code>foreignField</code> options. Mongoose will populate documents from the model in <code>ref</code> whose <code>foreignField</code> matches this document&#39;s <code>localField</code>.</li>
-</ul>
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> userSchema = mongoose.Schema({ _id: <span class="hljs-built_in">Number</span>, email: <span class="hljs-built_in">String</span> });
-<span class="hljs-keyword">const</span> blogPostSchema = mongoose.Schema({
-  title: <span class="hljs-built_in">String</span>,
-  authorId: <span class="hljs-built_in">Number</span>
-});
-<span class="hljs-comment">// When you `populate()` the `author` virtual, Mongoose will find the</span>
-<span class="hljs-comment">// first document in the User model whose `_id` matches this document's</span>
-<span class="hljs-comment">// `authorId` property.</span>
-blogPostSchema.virtual(<span class="hljs-string">'author'</span>, {
-  ref: <span class="hljs-string">'User'</span>,
-  localField: <span class="hljs-string">'authorId'</span>,
-  foreignField: <span class="hljs-string">'_id'</span>,
-  justOne: <span class="hljs-literal">true</span>
-});
-<span class="hljs-keyword">const</span> User = mongoose.model(<span class="hljs-string">'User'</span>, userSchema);
-<span class="hljs-keyword">const</span> BlogPost = mongoose.model(<span class="hljs-string">'BlogPost'</span>, blogPostSchema);
-
-<span class="hljs-keyword">await</span> BlogPost.create({ title: <span class="hljs-string">'Introduction to Mongoose'</span>, authorId: <span class="hljs-number">1</span> });
-<span class="hljs-keyword">await</span> User.create({ _id: <span class="hljs-number">1</span>, email: <span class="hljs-string">'test@gmail.com'</span> });
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">await</span> BlogPost.findOne().populate(<span class="hljs-string">'author'</span>);
-doc.author.email; <span class="hljs-comment">// 'test@gmail.com'</span></code></pre>
-<h2 id="further-reading">Further Reading</h2>
-<ul>
-<li><a href="/docs/guide.html#virtuals">Virtuals in Mongoose Schemas</a></li>
-<li><a href="/docs/populate.html#populate-virtuals">Populate Virtuals</a></li>
-<li><a href="https://plugins.mongoosejs.io/plugins/lean-virtuals">Mongoose Lean Virtuals plugin</a></li>
-<li><a href="https://masteringjs.io/tutorials/mongoose/virtuals">Getting Started With Mongoose Virtuals</a></li>
-<li><a href="https://futurestud.io/tutorials/understanding-virtuals-in-mongoose">Understanding Virtuals in Mongoose</a></li>
-</ul>
-</div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/docs/validation.html b/docs/validation.html
deleted file mode 100644
index a5e29d73303..00000000000
--- a/docs/validation.html
+++ /dev/null
@@ -1,540 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose v5.6.0: Validation</title><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="stylesheet" href="https://unpkg.com/purecss@1.0.0/build/pure-min.css" integrity="sha384-nn4HPE8lTHyVtfCBi5yW9d20FjT8BJwUXyWZT9InLYax14RDjBj46LmSztkmNP9w" crossorigin="anonymous"><link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Open+Sans"><link rel="stylesheet" href="/docs/css/github.css"><link rel="stylesheet" href="/docs/css/mongoose5.css"><link rel="apple-touch-icon" sizes="57x57" href="images/favicon/apple-icon-57x57.png"><link rel="apple-touch-icon" sizes="60x60" href="images/favicon/apple-icon-60x60.png"><link rel="apple-touch-icon" sizes="72x72" href="images/favicon/apple-icon-72x72.png"><link rel="apple-touch-icon" sizes="76x76" href="images/favicon/apple-icon-76x76.png"><link rel="apple-touch-icon" sizes="114x114" href="images/favicon/apple-icon-114x114.png"><link rel="apple-touch-icon" sizes="120x120" href="images/favicon/apple-icon-120x120.png"><link rel="apple-touch-icon" sizes="144x144" href="images/favicon/apple-icon-144x144.png"><link rel="apple-touch-icon" sizes="152x152" href="images/favicon/apple-icon-152x152.png"><link rel="apple-touch-icon" sizes="180x180" href="images/favicon/apple-icon-180x180.png"><link rel="icon" type="image/png" sizes="192x192" href="images/favicon/android-icon-192x192.png"><link rel="icon" type="image/png" sizes="32x32" href="images/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="96x96" href="images/favicon/favicon-96x96.png"><link rel="icon" type="image/png" sizes="16x16" href="images/favicon/favicon-16x16.png"><link rel="manifest" href="images/favicon/manifest.json"><meta name="msapplication-TileColor" content="#ffffff"><meta name="msapplication-TileImage" content="images/favicon/ms-icon-144x144.png"><meta name="theme-color" content="#ffffff"></head><body><div id="layout"><div id="mobile-menu"><a class="menu-link" id="menuLink" href="#menu"><span></span></a><div id="mobile-logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div></div><div id="menu"><div class="pure-menu"><div class="pure-menu-heading" id="logo-container"><a href="/"><img id="logo" src="/docs/images/mongoose5_62x30_transparent.png"><span class="logo-text">mongoose</span></a></div><ul class="pure-menu-list" id="navbar"><li class="pure-menu-horizontal pure-menu-item pure-menu-has-children pure-menu-allow-hover version"><a class="pure-menu-link" href="#">Version 5.6.0</a><ul class="pure-menu-children"><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/4.x">Version 4.13.18</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/3.8.x">Version 3.8.40</a></li></ul></li><li class="pure-menu-item search"><input id="search-input-nav" type="text" placeholder="Search"><button id="search-button-nav"><img src="/docs/images/search.svg"></button></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/index.html">Quick Start</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/guides.html">Guides</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/guide.html">Schemas</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/schematypes.html">SchemaTypes</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/connections.html">Connections</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/models.html">Models</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/documents.html">Documents</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/subdocs.html">Subdocuments</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/queries.html">Queries</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/validation.html">Validation</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/middleware.html">Middleware</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/populate.html">Populate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/discriminators.html">Discriminators</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/plugins.html">Plugins</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/api.html">API</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/mongoose.html">Mongoose</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schema.html">Schema</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/connection.html">Connection</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/document.html">Document</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/model.html">Model</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/query.html">Query</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/aggregate.html">Aggregate</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/schematype.html">SchemaType</a></li><li class="pure-menu-item sub-item"><a class="pure-menu-link" href="/docs/api/virtualtype.html">VirtualType</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/compatibility.html">Version Compatibility</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/faq.html">FAQ</a></li><li class="pure-menu-item"><a class="pure-menu-link" href="/docs/further_reading.html">Further Reading</a></li></ul><div class="cpc-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div></div></div><div class="container"><div id="content"><ul class="toc"><li><a href="##{block.identifier}">Validation</a></li><li><a href="##{block.identifier}">Built-in Validators</a></li><li><a href="##{block.identifier}">The <code>unique</code> Option is Not a Validator</a></li><li><a href="##{block.identifier}">Custom Validators</a></li><li><a href="##{block.identifier}">Async Custom Validators</a></li><li><a href="##{block.identifier}">Validation Errors</a></li><li><a href="##{block.identifier}">Cast Errors</a></li><li><a href="##{block.identifier}">Required Validators On Nested Objects</a></li><li><a href="##{block.identifier}">Update Validators</a></li><li><a href="##{block.identifier}">Update Validators and <code>this</code></a></li><li><a href="##{block.identifier}">The <code>context</code> option</a></li><li><a href="##{block.identifier}">Update Validators Only Run On Updated Paths</a></li><li><a href="##{block.identifier}">Update Validators Only Run For Some Operations</a></li><li><a href="##{block.identifier}">On $push and $addToSet</a></li></ul><h2 id="#{block.identifier}"><a href="##{block.identifier}">Validation</a></h2><p>Before we get into the specifics of validation syntax, please keep the following rules in mind:</p>
-<ul>
-<li>Validation is defined in the <a href="./schematypes.html">SchemaType</a></li>
-<li>Validation is <a href="./middleware.html">middleware</a>. Mongoose registers validation as a <code>pre(&#39;save&#39;)</code> hook on every schema by default.</li>
-<li>You can manually run validation using <code>doc.validate(callback)</code> or <code>doc.validateSync()</code></li>
-<li>Validators are not run on undefined values. The only exception is the <a href="./api.html#schematype_SchemaType-required"><code>required</code> validator</a>.</li>
-<li>Validation is asynchronously recursive; when you call <a href="./api.html#model_Model-save">Model#save</a>, sub-document validation is executed as well. If an error occurs, your <a href="./api.html#model_Model-save">Model#save</a> callback receives it</li>
-<li>Validation is customizable</li>
-</ul>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> schema = <span class="hljs-keyword">new</span> Schema({
-  name: {
-    type: <span class="hljs-built_in">String</span>,
-    required: <span class="hljs-literal">true</span>
-  }
-});
-<span class="hljs-keyword">var</span> Cat = db.model(<span class="hljs-string">'Cat'</span>, schema);
-
-<span class="hljs-comment">// This cat has no name :(</span>
-<span class="hljs-keyword">var</span> cat = <span class="hljs-keyword">new</span> Cat();
-cat.save(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  assert.equal(error.errors[<span class="hljs-string">'name'</span>].message,
-    <span class="hljs-string">'Path `name` is required.'</span>);
-
-  error = cat.validateSync();
-  assert.equal(error.errors[<span class="hljs-string">'name'</span>].message,
-    <span class="hljs-string">'Path `name` is required.'</span>);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Built-in Validators</a></h2><p>Mongoose has several built-in validators.</p>
-<ul>
-<li>All <a href="./schematypes.html">SchemaTypes</a> have the built-in <a href="./api.html#schematype_SchemaType-required">required</a> validator. The required validator uses the <a href="./api.html#schematype_SchemaType-checkRequired">SchemaType&#39;s <code>checkRequired()</code> function</a> to determine if the value satisfies the required validator.</li>
-<li><a href="./api.html#schema-number-js">Numbers</a> have <a href="./schematypes.html#number-validators"><code>min</code> and <code>max</code></a> validators.</li>
-<li><a href="./api.html#schema-string-js">Strings</a> have <a href="./schematypes.html#string-validators"><code>enum</code>, <code>match</code>, <code>minlength</code>, and <code>maxlength</code></a> validators.</li>
-</ul>
-<p>Each of the validator links above provide more information about how to enable them and customize their error messages.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> breakfastSchema = <span class="hljs-keyword">new</span> Schema({
-  eggs: {
-    type: <span class="hljs-built_in">Number</span>,
-    min: [<span class="hljs-number">6</span>, <span class="hljs-string">'Too few eggs'</span>],
-    max: <span class="hljs-number">12</span>
-  },
-  bacon: {
-    type: <span class="hljs-built_in">Number</span>,
-    required: [<span class="hljs-literal">true</span>, <span class="hljs-string">'Why no bacon?'</span>]
-  },
-  drink: {
-    type: <span class="hljs-built_in">String</span>,
-    enum: [<span class="hljs-string">'Coffee'</span>, <span class="hljs-string">'Tea'</span>],
-    required: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-      <span class="hljs-keyword">return</span> <span class="hljs-keyword">this</span>.bacon &gt; <span class="hljs-number">3</span>;
-    }
-  }
-});
-<span class="hljs-keyword">var</span> Breakfast = db.model(<span class="hljs-string">'Breakfast'</span>, breakfastSchema);
-
-<span class="hljs-keyword">var</span> badBreakfast = <span class="hljs-keyword">new</span> Breakfast({
-  eggs: <span class="hljs-number">2</span>,
-  bacon: <span class="hljs-number">0</span>,
-  drink: <span class="hljs-string">'Milk'</span>
-});
-<span class="hljs-keyword">var</span> error = badBreakfast.validateSync();
-assert.equal(error.errors[<span class="hljs-string">'eggs'</span>].message,
-  <span class="hljs-string">'Too few eggs'</span>);
-assert.ok(!error.errors[<span class="hljs-string">'bacon'</span>]);
-assert.equal(error.errors[<span class="hljs-string">'drink'</span>].message,
-  <span class="hljs-string">'`Milk` is not a valid enum value for path `drink`.'</span>);
-
-badBreakfast.bacon = <span class="hljs-number">5</span>;
-badBreakfast.drink = <span class="hljs-literal">null</span>;
-
-error = badBreakfast.validateSync();
-assert.equal(error.errors[<span class="hljs-string">'drink'</span>].message, <span class="hljs-string">'Path `drink` is required.'</span>);
-
-badBreakfast.bacon = <span class="hljs-literal">null</span>;
-error = badBreakfast.validateSync();
-assert.equal(error.errors[<span class="hljs-string">'bacon'</span>].message, <span class="hljs-string">'Why no bacon?'</span>);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">The <code>unique</code> Option is Not a Validator</a></h2><p>A common gotcha for beginners is that the <code>unique</code> option for schemas
-is <em>not</em> a validator. It&#39;s a convenient helper for building <a href="https://docs.mongodb.com/manual/core/index-unique/">MongoDB unique indexes</a>.
-See the <a href="/docs/faq.html">FAQ</a> for more information.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> uniqueUsernameSchema = <span class="hljs-keyword">new</span> Schema({
-  username: {
-    type: <span class="hljs-built_in">String</span>,
-    unique: <span class="hljs-literal">true</span>
-  }
-});
-<span class="hljs-keyword">var</span> U1 = db.model(<span class="hljs-string">'U1'</span>, uniqueUsernameSchema);
-<span class="hljs-keyword">var</span> U2 = db.model(<span class="hljs-string">'U2'</span>, uniqueUsernameSchema);
-
-<span class="hljs-keyword">var</span> dup = [{ username: <span class="hljs-string">'Val'</span> }, { username: <span class="hljs-string">'Val'</span> }];
-U1.create(dup, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// Race condition! This may save successfully, depending on whether</span>
-  <span class="hljs-comment">// MongoDB built the index before writing the 2 docs.</span>
-});
-
-<span class="hljs-comment">// Need to wait for the index to finish building before saving,</span>
-<span class="hljs-comment">// otherwise unique constraints may be violated.</span>
-U2.once(<span class="hljs-string">'index'</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  assert.ifError(error);
-  U2.create(dup, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-    <span class="hljs-comment">// Will error, but will *not* be a mongoose validation error, it will be</span>
-    <span class="hljs-comment">// a duplicate key error.</span>
-    assert.ok(error);
-    assert.ok(!error.errors);
-    assert.ok(error.message.indexOf(<span class="hljs-string">'duplicate key error'</span>) !== <span class="hljs-number">-1</span>);
-  });
-});
-
-<span class="hljs-comment">// There's also a promise-based equivalent to the event emitter API.</span>
-<span class="hljs-comment">// The `init()` function is idempotent and returns a promise that</span>
-<span class="hljs-comment">// will resolve once indexes are done building;</span>
-U2.init().then(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  U2.create(dup, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-    <span class="hljs-comment">// Will error, but will *not* be a mongoose validation error, it will be</span>
-    <span class="hljs-comment">// a duplicate key error.</span>
-    assert.ok(error);
-    assert.ok(!error.errors);
-    assert.ok(error.message.indexOf(<span class="hljs-string">'duplicate key error'</span>) !== <span class="hljs-number">-1</span>);
-  });
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Custom Validators</a></h2><p>If the built-in validators aren&#39;t enough, you can define custom validators
-to suit your needs.</p>
-<p>Custom validation is declared by passing a validation function.
-You can find detailed instructions on how to do this in the
-<a href="./api.html#schematype_SchemaType-validate"><code>SchemaType#validate()</code> API docs</a>.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  phone: {
-    type: <span class="hljs-built_in">String</span>,
-    validate: {
-      validator: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-        <span class="hljs-keyword">return</span> <span class="hljs-regexp">/\d{3}-\d{3}-\d{4}/</span>.test(v);
-      },
-      message: props =&gt; <span class="hljs-string">`<span class="hljs-subst">${props.value}</span> is not a valid phone number!`</span>
-    },
-    required: [<span class="hljs-literal">true</span>, <span class="hljs-string">'User phone number required'</span>]
-  }
-});
-
-<span class="hljs-keyword">var</span> User = db.model(<span class="hljs-string">'user'</span>, userSchema);
-<span class="hljs-keyword">var</span> user = <span class="hljs-keyword">new</span> User();
-<span class="hljs-keyword">var</span> error;
-
-user.phone = <span class="hljs-string">'555.0123'</span>;
-error = user.validateSync();
-assert.equal(error.errors[<span class="hljs-string">'phone'</span>].message,
-  <span class="hljs-string">'555.0123 is not a valid phone number!'</span>);
-
-user.phone = <span class="hljs-string">''</span>;
-error = user.validateSync();
-assert.equal(error.errors[<span class="hljs-string">'phone'</span>].message,
-  <span class="hljs-string">'User phone number required'</span>);
-
-user.phone = <span class="hljs-string">'201-555-0123'</span>;
-<span class="hljs-comment">// Validation succeeds! Phone number is defined</span>
-<span class="hljs-comment">// and fits `DDD-DDD-DDDD`</span>
-error = user.validateSync();
-assert.equal(error, <span class="hljs-literal">null</span>);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Async Custom Validators</a></h2><p>Custom validators can also be asynchronous. If your validator function
-returns a promise (like an <code>async</code> function), mongoose will wait for that
-promise to settle. If you prefer callbacks, set the <code>isAsync</code> option,
-and mongoose will pass a callback as the 2nd argument to your validator
-function.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> userSchema = <span class="hljs-keyword">new</span> Schema({
-  name: {
-    type: <span class="hljs-built_in">String</span>,
-    <span class="hljs-comment">// You can also make a validator async by returning a promise. If you</span>
-    <span class="hljs-comment">// return a promise, do **not** specify the `isAsync` option.</span>
-    validate: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-      <span class="hljs-keyword">return</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Promise</span>(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">resolve, reject</span>) </span>{
-        setTimeout(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-          resolve(<span class="hljs-literal">false</span>);
-        }, <span class="hljs-number">5</span>);
-      });
-    }
-  },
-  phone: {
-    type: <span class="hljs-built_in">String</span>,
-    validate: {
-      isAsync: <span class="hljs-literal">true</span>,
-      validator: <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v, cb</span>) </span>{
-        setTimeout(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-          <span class="hljs-keyword">var</span> phoneRegex = <span class="hljs-regexp">/\d{3}-\d{3}-\d{4}/</span>;
-          <span class="hljs-keyword">var</span> msg = v + <span class="hljs-string">' is not a valid phone number!'</span>;
-          <span class="hljs-comment">// First argument is a boolean, whether validator succeeded</span>
-          <span class="hljs-comment">// 2nd argument is an optional error message override</span>
-          cb(phoneRegex.test(v), msg);
-        }, <span class="hljs-number">5</span>);
-      },
-      <span class="hljs-comment">// Default error message, overridden by 2nd argument to `cb()` above</span>
-      message: <span class="hljs-string">'Default error message'</span>
-    },
-    required: [<span class="hljs-literal">true</span>, <span class="hljs-string">'User phone number required'</span>]
-  }
-});
-
-<span class="hljs-keyword">var</span> User = db.model(<span class="hljs-string">'User'</span>, userSchema);
-<span class="hljs-keyword">var</span> user = <span class="hljs-keyword">new</span> User();
-<span class="hljs-keyword">var</span> error;
-
-user.phone = <span class="hljs-string">'555.0123'</span>;
-user.name = <span class="hljs-string">'test'</span>;
-user.validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  assert.ok(error);
-  assert.equal(error.errors[<span class="hljs-string">'phone'</span>].message,
-    <span class="hljs-string">'555.0123 is not a valid phone number!'</span>);
-  assert.equal(error.errors[<span class="hljs-string">'name'</span>].message,
-    <span class="hljs-string">'Validator failed for path `name` with value `test`'</span>);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Validation Errors</a></h2><p>Errors returned after failed validation contain an <code>errors</code> object
-whose values are <code>ValidatorError</code> objects. Each
-<a href="./api.html#error-validation-js">ValidatorError</a> has <code>kind</code>, <code>path</code>,
-<code>value</code>, and <code>message</code> properties.
-A ValidatorError also may have a <code>reason</code> property. If an error was
-thrown in the validator, this property will contain the error that was
-thrown.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> toySchema = <span class="hljs-keyword">new</span> Schema({
-  color: <span class="hljs-built_in">String</span>,
-  name: <span class="hljs-built_in">String</span>
-});
-
-<span class="hljs-keyword">var</span> validator = <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-regexp">/red|white|gold/i</span>.test(value);
-};
-toySchema.path(<span class="hljs-string">'color'</span>).validate(validator,
-  <span class="hljs-string">'Color `{VALUE}` not valid'</span>, <span class="hljs-string">'Invalid color'</span>);
-toySchema.path(<span class="hljs-string">'name'</span>).validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-  <span class="hljs-keyword">if</span> (v !== <span class="hljs-string">'Turbo Man'</span>) {
-    <span class="hljs-keyword">throw</span> <span class="hljs-keyword">new</span> <span class="hljs-built_in">Error</span>(<span class="hljs-string">'Need to get a Turbo Man for Christmas'</span>);
-  }
-  <span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
-}, <span class="hljs-string">'Name `{VALUE}` is not valid'</span>);
-
-<span class="hljs-keyword">var</span> Toy = db.model(<span class="hljs-string">'Toy'</span>, toySchema);
-
-<span class="hljs-keyword">var</span> toy = <span class="hljs-keyword">new</span> Toy({ color: <span class="hljs-string">'Green'</span>, name: <span class="hljs-string">'Power Ranger'</span> });
-
-toy.save(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-comment">// `err` is a ValidationError object</span>
-  <span class="hljs-comment">// `err.errors.color` is a ValidatorError object</span>
-  assert.equal(err.errors.color.message, <span class="hljs-string">'Color `Green` not valid'</span>);
-  assert.equal(err.errors.color.kind, <span class="hljs-string">'Invalid color'</span>);
-  assert.equal(err.errors.color.path, <span class="hljs-string">'color'</span>);
-  assert.equal(err.errors.color.value, <span class="hljs-string">'Green'</span>);
-
-  <span class="hljs-comment">// This is new in mongoose 5. If your validator throws an exception,</span>
-  <span class="hljs-comment">// mongoose will use that message. If your validator returns `false`,</span>
-  <span class="hljs-comment">// mongoose will use the 'Name `Power Ranger` is not valid' message.</span>
-  assert.equal(err.errors.name.message,
-    <span class="hljs-string">'Need to get a Turbo Man for Christmas'</span>);
-  assert.equal(err.errors.name.value, <span class="hljs-string">'Power Ranger'</span>);
-  <span class="hljs-comment">// If your validator threw an error, the `reason` property will contain</span>
-  <span class="hljs-comment">// the original error thrown, including the original stack trace.</span>
-  assert.equal(err.errors.name.reason.message,
-    <span class="hljs-string">'Need to get a Turbo Man for Christmas'</span>);
-
-  assert.equal(err.name, <span class="hljs-string">'ValidationError'</span>);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Cast Errors</a></h2><p>Before running validators, Mongoose attempts to coerce values to the
-correct type. This process is called <em>casting</em> the document. If
-casting fails for a given path, the <code>error.errors</code> object will contain
-a <code>CastError</code> object.</p>
-<p>Casting runs before validation, and validation does not run if casting
-fails. That means your custom validators may assume <code>v</code> is <code>null</code>,
-<code>undefined</code>, or an instance of the type specified in your schema.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">const</span> vehicleSchema = <span class="hljs-keyword">new</span> mongoose.Schema({
-  numWheels: { type: <span class="hljs-built_in">Number</span>, max: <span class="hljs-number">18</span> }
-});
-<span class="hljs-keyword">const</span> Vehicle = db.model(<span class="hljs-string">'Vehicle'</span>, vehicleSchema);
-
-<span class="hljs-keyword">const</span> doc = <span class="hljs-keyword">new</span> Vehicle({ numWheels: <span class="hljs-string">'not a number'</span> });
-<span class="hljs-keyword">const</span> err = doc.validateSync();
-
-err.errors[<span class="hljs-string">'numWheels'</span>].name; <span class="hljs-comment">// 'CastError'</span>
-<span class="hljs-comment">// 'Cast to Number failed for value "not a number" at path "numWheels"'</span>
-err.errors[<span class="hljs-string">'numWheels'</span>].message;</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Required Validators On Nested Objects</a></h2><p>Defining validators on nested objects in mongoose is tricky, because
-nested objects are not fully fledged paths.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> personSchema = <span class="hljs-keyword">new</span> Schema({
-  name: {
-    first: <span class="hljs-built_in">String</span>,
-    last: <span class="hljs-built_in">String</span>
-  }
-});
-
-assert.throws(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
-  <span class="hljs-comment">// This throws an error, because 'name' isn't a full fledged path</span>
-  personSchema.path(<span class="hljs-string">'name'</span>).required(<span class="hljs-literal">true</span>);
-}, <span class="hljs-regexp">/Cannot.*'required'/</span>);
-
-<span class="hljs-comment">// To make a nested object required, use a single nested schema</span>
-<span class="hljs-keyword">var</span> nameSchema = <span class="hljs-keyword">new</span> Schema({
-  first: <span class="hljs-built_in">String</span>,
-  last: <span class="hljs-built_in">String</span>
-});
-
-personSchema = <span class="hljs-keyword">new</span> Schema({
-  name: {
-    type: nameSchema,
-    required: <span class="hljs-literal">true</span>
-  }
-});
-
-<span class="hljs-keyword">var</span> Person = db.model(<span class="hljs-string">'Person'</span>, personSchema);
-
-<span class="hljs-keyword">var</span> person = <span class="hljs-keyword">new</span> Person();
-<span class="hljs-keyword">var</span> error = person.validateSync();
-assert.ok(error.errors[<span class="hljs-string">'name'</span>]);</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Update Validators</a></h2><p>In the above examples, you learned about document validation. Mongoose also
-supports validation for <a href="/docs/api.html#query_Query-update"><code>update()</code></a>,
-<a href="/docs/api.html#query_Query-updateOne"><code>updateOne()</code></a>,
-<a href="/docs/api.html#query_Query-updateMany"><code>updateMany()</code></a>,
-and <a href="/docs/api.html#query_Query-findOneAndUpdate"><code>findOneAndUpdate()</code></a> operations.
-Update validators are off by default - you need to specify
-the <code>runValidators</code> option.</p>
-<p>To turn on update validators, set the <code>runValidators</code> option for
-<code>update()</code>, <code>updateOne()</code>, <code>updateMany()</code>, or <code>findOneAndUpdate()</code>.
-Be careful: update validators are off by default because they have several
-caveats.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> toySchema = <span class="hljs-keyword">new</span> Schema({
-  color: <span class="hljs-built_in">String</span>,
-  name: <span class="hljs-built_in">String</span>
-});
-
-<span class="hljs-keyword">var</span> Toy = db.model(<span class="hljs-string">'Toys'</span>, toySchema);
-
-Toy.schema.path(<span class="hljs-string">'color'</span>).validate(<span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">value</span>) </span>{
-  <span class="hljs-keyword">return</span> <span class="hljs-regexp">/red|green|blue/i</span>.test(value);
-}, <span class="hljs-string">'Invalid color'</span>);
-
-<span class="hljs-keyword">var</span> opts = { runValidators: <span class="hljs-literal">true</span> };
-Toy.updateOne({}, { color: <span class="hljs-string">'not a color'</span> }, opts, <span class="hljs-function"><span class="hljs-keyword">function</span> (<span class="hljs-params">err</span>) </span>{
-  assert.equal(err.errors.color.message,
-    <span class="hljs-string">'Invalid color'</span>);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Update Validators and <code>this</code></a></h2><p>There are a couple of key differences between update validators and
-document validators. In the color validation function above, <code>this</code> refers
-to the document being validated when using document validation.
-However, when running update validators, the document being updated
-may not be in the server&#39;s memory, so by default the value of <code>this</code> is
-not defined.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> toySchema = <span class="hljs-keyword">new</span> Schema({
-  color: <span class="hljs-built_in">String</span>,
-  name: <span class="hljs-built_in">String</span>
-});
-
-toySchema.path(<span class="hljs-string">'color'</span>).validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value</span>) </span>{
-  <span class="hljs-comment">// When running in `validate()` or `validateSync()`, the</span>
-  <span class="hljs-comment">// validator can access the document using `this`.</span>
-  <span class="hljs-comment">// Does **not** work with update validators.</span>
-  <span class="hljs-keyword">if</span> (<span class="hljs-keyword">this</span>.name.toLowerCase().indexOf(<span class="hljs-string">'red'</span>) !== <span class="hljs-number">-1</span>) {
-    <span class="hljs-keyword">return</span> value !== <span class="hljs-string">'red'</span>;
-  }
-  <span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
-});
-
-<span class="hljs-keyword">var</span> Toy = db.model(<span class="hljs-string">'ActionFigure'</span>, toySchema);
-
-<span class="hljs-keyword">var</span> toy = <span class="hljs-keyword">new</span> Toy({ color: <span class="hljs-string">'red'</span>, name: <span class="hljs-string">'Red Power Ranger'</span> });
-<span class="hljs-keyword">var</span> error = toy.validateSync();
-assert.ok(error.errors[<span class="hljs-string">'color'</span>]);
-
-<span class="hljs-keyword">var</span> update = { color: <span class="hljs-string">'red'</span>, name: <span class="hljs-string">'Red Power Ranger'</span> };
-<span class="hljs-keyword">var</span> opts = { runValidators: <span class="hljs-literal">true</span> };
-
-Toy.updateOne({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// The update validator throws an error:</span>
-  <span class="hljs-comment">// "TypeError: Cannot read property 'toLowerCase' of undefined",</span>
-  <span class="hljs-comment">// because `this` is **not** the document being updated when using</span>
-  <span class="hljs-comment">// update validators</span>
-  assert.ok(error);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">The <code>context</code> option</a></h2><p>The <code>context</code> option lets you set the value of <code>this</code> in update validators
-to the underlying query.</p>
-
-<pre><code class="language-javascript">toySchema.path(<span class="hljs-string">'color'</span>).validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">value</span>) </span>{
-  <span class="hljs-comment">// When running update validators with the `context` option set to</span>
-  <span class="hljs-comment">// 'query', `this` refers to the query object.</span>
-  <span class="hljs-keyword">if</span> (<span class="hljs-keyword">this</span>.getUpdate().$set.name.toLowerCase().indexOf(<span class="hljs-string">'red'</span>) !== <span class="hljs-number">-1</span>) {
-    <span class="hljs-keyword">return</span> value === <span class="hljs-string">'red'</span>;
-  }
-  <span class="hljs-keyword">return</span> <span class="hljs-literal">true</span>;
-});
-
-<span class="hljs-keyword">var</span> Toy = db.model(<span class="hljs-string">'Figure'</span>, toySchema);
-
-<span class="hljs-keyword">var</span> update = { color: <span class="hljs-string">'blue'</span>, name: <span class="hljs-string">'Red Power Ranger'</span> };
-<span class="hljs-comment">// Note the context option</span>
-<span class="hljs-keyword">var</span> opts = { runValidators: <span class="hljs-literal">true</span>, context: <span class="hljs-string">'query'</span> };
-
-Toy.updateOne({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  assert.ok(error.errors[<span class="hljs-string">'color'</span>]);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Update Validators Only Run On Updated Paths</a></h2><p>The other key difference that update validators only run on the paths
-specified in the update. For instance, in the below example, because
-&#39;name&#39; is not specified in the update operation, update validation will
-succeed.</p>
-<p>When using update validators, <code>required</code> validators <strong>only</strong> fail when
-you try to explicitly <code>$unset</code> the key.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> kittenSchema = <span class="hljs-keyword">new</span> Schema({
-  name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> },
-  age: <span class="hljs-built_in">Number</span>
-});
-
-<span class="hljs-keyword">var</span> Kitten = db.model(<span class="hljs-string">'Kitten'</span>, kittenSchema);
-
-<span class="hljs-keyword">var</span> update = { color: <span class="hljs-string">'blue'</span> };
-<span class="hljs-keyword">var</span> opts = { runValidators: <span class="hljs-literal">true</span> };
-Kitten.updateOne({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-comment">// Operation succeeds despite the fact that 'name' is not specified</span>
-});
-
-<span class="hljs-keyword">var</span> unset = { $unset: { name: <span class="hljs-number">1</span> } };
-Kitten.updateOne({}, unset, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">err</span>) </span>{
-  <span class="hljs-comment">// Operation fails because 'name' is required</span>
-  assert.ok(err);
-  assert.ok(err.errors[<span class="hljs-string">'name'</span>]);
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">Update Validators Only Run For Some Operations</a></h2><p>One final detail worth noting: update validators <strong>only</strong> run on the
-following update operators:</p>
-<ul>
-<li><code>$set</code></li>
-<li><code>$unset</code></li>
-<li><code>$push</code> (&gt;= 4.8.0)</li>
-<li><code>$addToSet</code> (&gt;= 4.8.0)</li>
-<li><code>$pull</code> (&gt;= 4.12.0)</li>
-<li><code>$pullAll</code> (&gt;= 4.12.0)</li>
-</ul>
-<p>For instance, the below update will succeed, regardless of the value of
-<code>number</code>, because update validators ignore <code>$inc</code>.</p>
-<p>Also, <code>$push</code>, <code>$addToSet</code>, <code>$pull</code>, and <code>$pullAll</code> validation does
-<strong>not</strong> run any validation on the array itself, only individual elements
-of the array.</p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> testSchema = <span class="hljs-keyword">new</span> Schema({
-  number: { type: <span class="hljs-built_in">Number</span>, max: <span class="hljs-number">0</span> },
-  arr: [{ message: { type: <span class="hljs-built_in">String</span>, maxlength: <span class="hljs-number">10</span> } }]
-});
-
-<span class="hljs-comment">// Update validators won't check this, so you can still `$push` 2 elements</span>
-<span class="hljs-comment">// onto the array, so long as they don't have a `message` that's too long.</span>
-testSchema.path(<span class="hljs-string">'arr'</span>).validate(<span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">v</span>) </span>{
-  <span class="hljs-keyword">return</span> v.length &lt; <span class="hljs-number">2</span>;
-});
-
-<span class="hljs-keyword">var</span> Test = db.model(<span class="hljs-string">'Test'</span>, testSchema);
-
-<span class="hljs-keyword">var</span> update = { $inc: { number: <span class="hljs-number">1</span> } };
-<span class="hljs-keyword">var</span> opts = { runValidators: <span class="hljs-literal">true</span> };
-Test.updateOne({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  <span class="hljs-comment">// There will never be a validation error here</span>
-  update = { $push: [{ message: <span class="hljs-string">'hello'</span> }, { message: <span class="hljs-string">'world'</span> }] };
-  Test.updateOne({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-    <span class="hljs-comment">// This will never error either even though the array will have at</span>
-    <span class="hljs-comment">// least 2 elements.</span>
-  });
-});</code></pre>
-<h2 id="#{block.identifier}"><a href="##{block.identifier}">On $push and $addToSet</a></h2><p>New in 4.8.0: update validators also run on <code>$push</code> and <code>$addToSet</code></p>
-
-<pre><code class="language-javascript"><span class="hljs-keyword">var</span> testSchema = <span class="hljs-keyword">new</span> Schema({
-  numbers: [{ type: <span class="hljs-built_in">Number</span>, max: <span class="hljs-number">0</span> }],
-  docs: [{
-    name: { type: <span class="hljs-built_in">String</span>, required: <span class="hljs-literal">true</span> }
-  }]
-});
-
-<span class="hljs-keyword">var</span> Test = db.model(<span class="hljs-string">'TestPush'</span>, testSchema);
-
-<span class="hljs-keyword">var</span> update = {
-  $push: {
-    numbers: <span class="hljs-number">1</span>,
-    docs: { name: <span class="hljs-literal">null</span> }
-  }
-};
-<span class="hljs-keyword">var</span> opts = { runValidators: <span class="hljs-literal">true</span> };
-Test.updateOne({}, update, opts, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params">error</span>) </span>{
-  assert.ok(error.errors[<span class="hljs-string">'numbers'</span>]);
-  assert.ok(error.errors[<span class="hljs-string">'docs'</span>]);
-});</code></pre>
-<div class="suffix"></div></div></div><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script><script type="text/javascript" src="/docs/js/navbar-search.js"></script><script type="text/javascript">(function (window, document) {
-  var layout   = document.getElementById('layout'),
-      menu     = document.getElementById('menu'),
-      menuLink = document.getElementById('menuLink'),
-      content  = document.getElementById('content');
-
-  function toggleClass(element, className) {
-      var classes = element.className.split(/\s+/),
-          length = classes.length,
-          i = 0;
-
-      for(; i < length; i++) {
-        if (classes[i] === className) {
-          classes.splice(i, 1);
-          break;
-        }
-      }
-      // The className is not found
-      if (length === classes.length) {
-          classes.push(className);
-      }
-
-      element.className = classes.join(' ');
-  }
-
-  function toggleAll(e) {
-      var active = 'active';
-
-      e.preventDefault();
-      toggleClass(layout, active);
-      toggleClass(menu, active);
-      toggleClass(menuLink, active);
-  }
-
-  menuLink.onclick = function (e) {
-      toggleAll(e);
-  };
-
-  content.onclick = function(e) {
-      if (menu.className.indexOf('active') !== -1) {
-          toggleAll(e);
-      }
-  };
-
-}(this, this.document));</script></div></body></html>
\ No newline at end of file
diff --git a/index.html b/index.html
deleted file mode 100644
index 2846a178710..00000000000
--- a/index.html
+++ /dev/null
@@ -1,166 +0,0 @@
-<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>Mongoose ODM v5.6.0</title><link href="//fonts.googleapis.com/css?family=Anonymous+Pro:400,700|Droid+Sans+Mono|Open+Sans:400,700|Linden+Hill|Quattrocento:400,700|News+Cycle:400,700|Antic+Slab|Cabin+Condensed:400,700" rel="stylesheet" type="text/css"><link href="docs/css/default.css" rel="stylesheet"><link href="docs/css/style.css" rel="stylesheet"><link href="/docs/css/github.css" rel="stylesheet"><style>code {
-  font-size: 1em;
-}
-
-.sponsor {
-  margin-bottom: 40px;
-  font-size: 0.66em;
-  color: #666;
-  text-decoration: none;
-}
-
-.sponsors {
-  margin-bottom: 40px;
-}
-
-.sponsors a {
-  text-decoration: none;
-}
-
-.carbonad{
-  margin-top:0!important;
-  margin-bottom:-3rem!important
-}
-
-#carbonads {
-  position:fixed;
-  right: 0px;
-  bottom: 0px;
-  display:block;
-  width:200px;
-  padding:15px 15px 15px 160px;
-  overflow:hidden;
-  font-size:13px;
-  line-height:1.4;
-  text-align:left;
-  background-color: #fafafa;
-}
-
-@media (max-width: 1160px) {
-  #carbonads {
-    display: none !important;
-  }
-}
-
-#carbonads a{color:#333;text-decoration:none}
-
-.carbon-img{float:left;margin-left:-145px}
-
-.carbon-poweredby{display:block;color:#777!important}
-
-img.sponsor {
-  margin-right: 10px;
-  border: 1px dotted #dfdfdf;
-  height: 100px;
-}
-</style></head><body><a id="forkbanner" href="http://github.com/learnboost/mongoose"><img style="position: absolute; top: 0; right: 0; border: 0;" src="https://s3.amazonaws.com/github/ribbons/forkme_right_gray_6d6d6d.png" alt="Fork me on GitHub"></a><div class="homepage" id="wrap"><div id="header"><h1><a href="https://github.com/Automattic/mongoose" target="blank"><div class="mongoose">Mongoose</div></a></h1></div><div class="tagline"><p>Elegant <a href="https://www.mongodb.com/">MongoDB</a> object modeling for
-<a href="https://nodejs.org/en/">Node.js</a></p>
-</div><div id="links"><ul><li><a href="docs/guide.html">Read the Docs</a></li><li><a href="http://plugins.mongoosejs.io">Discover Plugins</a></li></ul></div><div id="follow"><ul><li><iframe class="github-btn" src="//ghbtns.com/github-btn.html?user=Automattic&amp;repo=mongoose&amp;type=watch&amp;count=true" allowtransparency="true" frameborder="0" scrolling="0" width="100px" height="20px"></iframe></li><li id="version"><span>Version 5.6.0</span></li><li><iframe class="github-btn" src="//ghbtns.com/github-btn.html?user=Automattic&amp;repo=mongoose&amp;type=fork&amp;count=true" allowtransparency="true" frameborder="0" scrolling="0" width="100px" height="20px"></iframe></li></ul></div><div id="inner"><div id="what"><p class="what">Let's face it,&nbsp;<strong>writing MongoDB validation, casting and business logic boilerplate is a drag</strong>. That's why we wrote Mongoose.</p></div><pre><code class="language-javascript"><span class="hljs-keyword">const</span> mongoose = <span class="hljs-built_in">require</span>(<span class="hljs-string">'mongoose'</span>);
-mongoose.connect(<span class="hljs-string">'mongodb://localhost:27017/test'</span>, {useNewUrlParser: <span class="hljs-literal">true</span>});
-
-<span class="hljs-keyword">const</span> Cat = mongoose.model(<span class="hljs-string">'Cat'</span>, { name: <span class="hljs-built_in">String</span> });
-
-<span class="hljs-keyword">const</span> kitty = <span class="hljs-keyword">new</span> Cat({ name: <span class="hljs-string">'Zildjian'</span> });
-kitty.save().then(() =&gt; <span class="hljs-built_in">console</span>.log(<span class="hljs-string">'meow'</span>));</code></pre>
-<p>Mongoose provides a straight-forward, schema-based solution to model
-your application data. It includes built-in type casting, validation,
-query building, business logic hooks and more, out of the box.</p>
-<div id="tidelift"><a id="tidelift-button" href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=website">
-  <img src="/docs/images/tidelift.svg" />
-  <span>Get Professionally Supported Mongoose</span>
-</a>
-</div><div class="carbon-ad"><script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script></div><h2 id="getting-started">Getting Started</h2>
-<ul>
-<li><a href="/docs/index.html">quick start guide</a></li>
-</ul>
-<h2 id="support">Support</h2>
-<ul>
-<li><a href="http://stackoverflow.com/questions/tagged/mongoose">Stack Overflow</a></li>
-<li><a href="https://github.com/Automattic/mongoose/issues">GitHub Issues</a></li>
-<li><a href="https://gitter.im/Automattic/mongoose">Gitter Chat</a></li>
-<li><a href="http://www.mongodb.org/about/support/">MongoDB Support</a></li>
-</ul>
-<h2 id="news">News</h2>
-<ul>
-<li><a href="https://twitter.com/mongoosejs">Twitter</a></li>
-</ul>
-<h2 id="changelog">Changelog</h2>
-<ul>
-<li><a href="https://github.com/Automattic/mongoose/blob/master/History.md">Changelog</a></li>
-</ul>
-<h2 id="sponsors">Sponsors</h2>
-<div class="sponsors">
-  <div>
-    <a href="https://mixmax.com">
-      <img class="sponsor" src="/docs/images/mixmax.png" alt="MixMax.com">
-    </a>
-    <a href="https://localizejs.com/">
-      <img class="sponsor" src="//ww1.prweb.com/prfiles/2015/10/28/13050459/localize-logo-black.png">
-    </a>
-    <a href="https://www.codefirst.co.uk/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fdde88120-e914-11e8-a662-278259d35390.png&height=100">
-    </a>
-    <a href="https://www.vpsserver.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fvpsserver.com&height=100">
-    </a>
-    <a href="https://icons8.com/">
-      <img class="sponsor" src="https://s3.amazonaws.com/codebarbarian-images/Icons8+Logo+500px.png" style="height:100px">
-    </a>
-    <a href="https://topvet.net/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Ftopvet.net&height=100" style="height:100px">
-    </a>
-    <a href="https://www.dontpayfull.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F84c4ba80-1955-11e8-8343-278614155b3e.png&height=100" style="height:100px">
-    </a>
-    <a href="https://marcus-hiles.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fwww.gravatar.com%2Favatar%2F18234f5f0ed822f7b879f50b285c47eb%3Fdefault%3D404&height=100" style="height:100px">
-    </a>
-    <a href="https://craftresumes.com/professional-resume-writer/">
-      <img class="sponsor" alt="Professional resume writer" src="https://s3.amazonaws.com/codebarbarian-images/craftresumes.png">
-    </a>
-    <a href="https://domainwheel.com/">
-      <img class="sponsor" src="https://s25990.pcdn.co/wp-content/themes/namegenerator/img/logo_dw.jpg" style="height:100px">
-    </a>
-    <a href="https://uiuxagencies.top/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F62223ab0-f4f7-11e8-919f-53f2ea21a967.png&height=100" style="height:100px">
-    </a>
-    <a href="https://www.promocodewatch.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2Fbd0053f0-4f64-11e9-8022-91853c58485e.png&height=100" style="height:100px">
-    </a>
-    <a href="https://www.vpnranks.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fvpnranks.com&height=100" style="height:100px">
-    </a>
-    <a href="https://www.bestvpn.co/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fwww.bestvpn.co&height=100" style="height:100px">
-    </a>
-    <a href="https://blokt.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Flogo.clearbit.com%2Fblokt.com&height=100" style="height:100px">
-    </a>
-    <a href="https://paperleaf.ca/">
-      <img class="sponsor" alt="Essay writing service in Canada" src="https://s3.amazonaws.com/codebarbarian-images/paperleaf.jpg">
-    </a>
-    <a href="https://usave.co.uk/utilities/broadband/">
-      <img class="sponsor" title="Compare broadband deals with usave" src="https://usave.co.uk/img/brand/brand-logo.png" style="height:100px">
-    </a>
-    <a href="http://clay.global/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F09d57c90-637c-11e7-9ed2-bfa12b0351e8.jpg&height=100" style="height: 100px">
-    </a>
-    <a href="https://tekhattan.com/">
-      <img class="sponsor" src="https://images.opencollective.com/proxy/images?src=https%3A%2F%2Fopencollective-production.s3-us-west-1.amazonaws.com%2F31835450-5a98-11e9-adb1-e17fccd4c65e.png&height=80" style="height:80px">
-    </a>
-  </div>
-</div>
-
-<div class="sponsor">
-  Sponsor <a href="https://opencollective.com/mongoose">Mongoose on OpenCollective</a>
-  to get your company's logo above!
-</div>
-</div></div><p id="footer">Licensed under MIT. Copyright 2011 <a href="http://learnboost.com">LearnBoost</a>.</p><script>document.body.className = 'load';</script><script type="text/javascript">var xhr = new XMLHttpRequest();
-xhr.open('POST', 'https://g0a3nbw0xa.execute-api.us-east-1.amazonaws.com/prod/track', true);
-xhr.setRequestHeader('Content-Type', 'application/json');
-xhr.onreadystatechange = function() {};
-xhr.send(JSON.stringify({
-  path: window.location.pathname,
-  hostname: window.location.hostname,
-  hash: window.location.hash
-}));</script></body></html>
\ No newline at end of file

From 43ce79430bfcf4c6e3a4ee186c96c3f767079bef Mon Sep 17 00:00:00 2001
From: Sanjib Ahmad <sanjib@sanjib.org>
Date: Wed, 19 May 2021 15:08:15 +0800
Subject: [PATCH 2054/2348] fix typo: preferences

---
 lib/query.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/query.js b/lib/query.js
index 0f7fd5da67a..da5be864214 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -1034,7 +1034,7 @@ Query.prototype.select = function select() {
  *     // read from secondaries with matching tags
  *     new Query().read('s', [{ dc:'sf', s: 1 },{ dc:'ma', s: 2 }])
  *
- * Read more about how to use read preferrences [here](http://docs.mongodb.org/manual/applications/replication/#read-preference) and [here](http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences).
+ * Read more about how to use read preferences [here](http://docs.mongodb.org/manual/applications/replication/#read-preference) and [here](http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences).
  *
  * @method read
  * @memberOf Query

From 4c7c7e1b1709c5b3073b4a1ba1a991bcea9691cb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 19 May 2021 12:44:37 -0400
Subject: [PATCH 2055/2348] refactor: move async/await tutorial from pug to md
 re: #10271

---
 docs/async-await.md  | 151 +++++++++++++++++++++++++++++++++++++
 docs/async-await.pug | 172 -------------------------------------------
 docs/source/index.js |   3 +-
 website.js           |   7 +-
 4 files changed, 157 insertions(+), 176 deletions(-)
 create mode 100644 docs/async-await.md
 delete mode 100644 docs/async-await.pug

diff --git a/docs/async-await.md b/docs/async-await.md
new file mode 100644
index 00000000000..d68616299f4
--- /dev/null
+++ b/docs/async-await.md
@@ -0,0 +1,151 @@
+# Using Async/Await with Mongoose
+
+* [Basic Use](#basic-use)
+* [Async Functions](#async-functions)
+* [Queries](#queries)
+
+### Basic Use
+
+Async/await lets us write asynchronous code as if it were synchronous. 
+This is especially helpful for avoiding callback hell when executing multiple async operations in sequence--a common scenario when working with Mongoose.
+Each of the three functions below retrieves a record from the database, updates it, and prints the updated record to the console.
+
+```javascript
+// Works.
+function callbackUpdate() {
+  MyModel.findOne({firstName: 'franklin', lastName: 'roosevelt'}, function(err, doc) {
+    if(err) {
+      handleError(err);
+    }
+
+    doc.middleName = 'delano';
+
+    doc.save(function(err, updatedDoc) {
+      if(err) {
+        handleError(err);
+      }
+
+      // Final logic is 2 callbacks deep
+      console.log(updatedDoc);
+    }); 
+  })
+}
+
+// Better.
+function thenUpdate() {
+  MyModel.findOne({firstName: 'franklin', lastName: 'roosevelt'})
+    .then(function(doc) {
+      doc.middleName = 'delano';
+      return doc.save();
+    })
+    .then(console.log)
+    .catch(function(err) {
+      handleError(err);
+    });
+};
+
+// Best?
+async function awaitUpdate() {
+  try {
+    const doc = await MyModel.findOne({
+      firstName: 'franklin',
+      lastName: 'roosevelt'
+    });
+
+    doc.middleName = 'delano';
+        
+    console.log(await doc.save());
+  }
+  catch(err) {
+    handleError(err);
+  }
+}
+```
+
+Note that the specific fulfillment values of different Mongoose methods vary, and may be affected by configuration. Please refer to the [API documentation](./api.html) for information about specific methods.
+
+### Async Functions
+
+Adding the keyword *async* to a JavaScript function automatically causes it to return a native JavaScript promise.
+This is true [regardless of the return value we specify in the function body](http://thecodebarbarian.com/async-functions-in-javascript.html#an-async-function-always-returns-a-promise).     
+
+```javascript
+async function getUser() {
+  //Inside getUser, we can await an async operation and interact with 
+  //foundUser as a normal, non-promise value...
+  const foundUser = await User.findOne({name: 'bill'});
+
+  console.log(foundUser); //Prints '{name: 'bill', admin: false}'
+  return foundUser;
+}
+
+//However, because async functions always return a promise, 
+//user is a promise.
+const user = getUser();
+
+console.log(user)  //Oops.  Prints '[Promise]'
+```
+
+Instead, treat the return value of an async function as you would any other promise.  Await its fulfillment inside another async function, or chain onto it using `.then` blocks.
+
+```javascript
+async function getUser() {
+  const foundUser = await User.findOne({name: 'bill'});
+  return foundUser;
+};
+
+async function doStuffWithUser() {
+  //Await the promise returned from calling getUser.
+  const user = await getUser();
+
+  console.log(user);  //Prints '{name: 'bill', admin: false}'
+}
+```
+
+<h3 id="queries">Async/Await with Mongoose Queries</h3>
+
+Under the hood, [async/await is syntactic sugar](https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Asynchronous/Async_await) over the Promise API.
+Due to the surprisingly simple way promises are implemented in JavaScript, the keyword `await` will try to unwrap any object with a property whose key is the string ‘then’ and whose value is a function. 
+Such objects belong to a broader class of objects called [thenables](https://masteringjs.io/tutorials/fundamentals/thenable). 
+If the thenable being unwrapped is a genuine promise, e.g. an instance of the [Promise constructor](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise), we enjoy several guarantees about how the object’s ‘then’ function will behave. 
+However, Mongoose provides several static helper methods that return a different class of thenable object called a [Query](./queries.html)--and [Queries are not promises](./queries.html#queries-are-not-promises). 
+Because Queries are also *thenables*, we can interact with a Query using async/await just as we would interact with a genuine promise, with one key difference: observing the fulfillment value of a genuine promise cannot under any circumstances change that value, but trying to re-observe the value of a Query may cause the Query to be re-executed.
+
+```javascript
+function isPromise(thenable) {
+  return thenable instanceof Promise;
+};
+
+// The fulfillment value of the promise returned by user.save() will always be the same,
+// regardless of how, or how often, we observe it.
+async function observePromise() {
+  const user = await User.findOne({firstName: 'franklin', lastName:'roosevelt'});
+
+  user.middleName = 'delano';
+
+  // Document.prototype.save() returns a *genuine* promise
+  const realPromise = user.save();
+
+  console.log(isPromise(realPromise)); //true
+
+  const awaitedValue = await realPromise;
+
+  realPromise.then(chainedValue => console.log(chainedValue === awaitedValue));   //true
+}
+
+// By contrast, the value we receive when we try to observe the same Query more than 
+// once is different every time.  The Query is re-executing.
+async function observeQuery() {
+  const query = User.findOne({firstname: 'leroy', lastName: 'jenkins'});
+
+  console.log(isPromise(query));  //false
+
+  const awaitedValue = await query;
+
+  query.then(chainedValue => console.log(chainedValue === awaitedValue)); //false
+}
+```
+
+You are most likely to accidentally re-execute queries in this way when mixing callbacks with async/await.
+ This is never necessary and should be avoided.
+ If you need a Query to return a fully-fleged promise instead of a thenable, you can use [Query#exec()](./api/query.html#query_Query-exec).
\ No newline at end of file
diff --git a/docs/async-await.pug b/docs/async-await.pug
deleted file mode 100644
index 9429e4d8dd9..00000000000
--- a/docs/async-await.pug
+++ /dev/null
@@ -1,172 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Async/Await
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-  ul
-    li
-      a(href="#basic-use") Basic Use
-    li
-      a(href="#async-functions") Async Functions
-    li
-      a(href="#queries") Queries
-
-  h3(id="basic-use") Basic Use
-  :markdown
-    Async/await lets us write asynchronous code as if it were synchronous.  This is especially helpful for avoiding callback hell when executing multiple async operations in sequence--a common scenario when working with Mongoose.  Each of the three functions below retrieves a record from the database, updates it,
-    and prints the updated record to the console.
-
-    ```javascript
-    // Works.
-    function callbackUpdate() {
-        MyModel.findOne({firstName: 'franklin', lastName: 'roosevelt'}, function(err, doc) {
-            if(err) {
-                handleError(err);
-            }
-
-            doc.middleName = 'delano';
-
-            doc.save(function(err, updatedDoc) {
-                if(err) {
-                    handleError(err);
-                }
-
-                // Final logic is 2 callbacks deep
-                console.log(updatedDoc);
-            }); 
-        })
-    }
-
-    // Better.
-    function thenUpdate() {
-        MyModel.findOne({firstName: 'franklin', lastName: 'roosevelt'})
-            .then(function(doc) {
-                doc.middleName = 'delano';
-                return doc.save();
-            })
-            .then(console.log)
-            .catch(function(err) {
-                handleError(err);
-            });
-    };
-
-    // Best?
-    async function awaitUpdate() {
-        try {
-            const doc = await MyModel.findOne({
-              firstName: 'franklin',
-              lastName: 'roosevelt'
-            });
-
-            doc.middleName = 'delano';
-        
-            console.log(await doc.save());
-        }
-        
-        catch(err) {
-            handleError(err);
-        }
-    }
-    ```
-  :markdown
-    Note that the specific fulfillment values of different Mongoose methods vary, and may be affected by configuration. Please refer to the [API documentation](./api.html) for information about specific methods.
-
-  h3(id="async-functions") Async Functions
-  :markdown
-    Adding the keyword *async* to a JavaScript function automatically causes it to return a native JavaScript promise.  This is true [regardless of the return value we specify in the function body](http://thecodebarbarian.com/async-functions-in-javascript.html#an-async-function-always-returns-a-promise).     
-
-    ```javascript
-    async function getUser() {
-      //Inside getUser, we can await an async operation and interact with 
-      //foundUser as a normal, non-promise value...
-      const foundUser = await User.findOne({name: 'bill'});
-
-      console.log(foundUser); //Prints '{name: 'bill', admin: false}'
-      return foundUser;
-    }
-
-    //However, because async functions always return a promise, 
-    //user is a promise.
-    const user = getUser();
-
-    console.log(user)  //Oops.  Prints '[Promise]'
-    ```
-  :markdown
-    Instead, treat the return value of an async function as you would any other promise.  Await its fulfillment inside another async function, or chain onto it using ‘.then’ blocks.
-
-    ```javascript
-    async function getUser() {
-      const foundUser = await User.findOne({name: 'bill'});
-      return foundUser;
-    };
-
-    async function doStuffWithUser() {
-      //Await the promise returned from calling getUser.
-      const user = await getUser();
-
-      console.log(user);  //Prints '{name: 'bill', admin: false}'
-    }
-
-  h3(id="queries") Async/Await with Mongoose Queries
-  :markdown
-    Under the hood, [*async/await* is syntactic sugar](https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Asynchronous/Async_await)
-    over the Promise API.  Due to the surprisingly simple way promises are implemented in JavaScript, the keyword *await* will try to unwrap any object with a property whose key is the string ‘then’ and whose value is a function.  Such objects belong to a broader class of objects called thenables.  If the thenable being unwrapped is a genuine promise, e.g. an instance of the [Promise constructor](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise), we enjoy several guarantees about how the object’s ‘then’ function will behave.  However, Mongoose provides several static helper methods that return a different class of thenable object called a [Query](./queries.html)--and [Queries are not promises](./queries.html#queries-are-not-promises).  Because Queries are also *thenables*, we can interact with a Query using async/await just as we would interact with a genuine promise, with one key difference: observing the fulfillment value of a genuine promise cannot under any circumstances change that value, but trying to re-observe the value of a Query may cause the Query to be re-executed.
-
-    ```javascript
-    function isPromise(thenable) {
-        return thenable instanceof Promise;
-    };
-
-    // The fulfillment value of the promise returned by user.save() will always be the same,
-    // regardless of how, or how often, we observe it.
-    async function observePromise() {
-        const user = await User.findOne({firstName: 'franklin', lastName:'roosevelt'});
-
-        user.middleName = 'delano';
-
-        // Document.prototype.save() returns a *genuine* promise
-        const realPromise = user.save();
-
-        console.log(isPromise(realPromise)); //true
-
-        const awaitedValue = await realPromise;
-
-        realPromise.then(chainedValue => console.log(chainedValue === awaitedValue));   //true
-    }
-
-    // By contrast, the value we receive when we try to observe the same Query more than 
-    // once is different every time.  The Query is re-executing.
-    async function observeQuery() {
-        const query = User.findOne({firstname: 'leroy', lastName: 'jenkins'});
-
-        console.log(isPromise(query));  //false
-
-        const awaitedValue = await query;
-
-        query.then(chainedValue => console.log(chainedValue === awaitedValue)); //false
-    }
-    ```
-  :markdown
-    You are most likely to accidentally re-execute queries in this way when mixing callbacks with async/await.  This is never necessary and should be avoided.  If you need a Query to return a fully-fleged promise instead of a thenable, you can use [Query#exec()](./api/query.html#query_Query-exec).
-    
-    
-  
diff --git a/docs/source/index.js b/docs/source/index.js
index 56b7a791e65..a4b85f6a868 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -34,4 +34,5 @@ exports['docs/compatibility.pug'] = {
 };
 exports['docs/search.pug'] = { title: 'Search' };
 exports['docs/enterprise.pug'] = { title: 'Mongoose for Enterprise' };
-exports['docs/built-with-mongoose.pug'] = { title: 'Built with Mongoose' };
\ No newline at end of file
+exports['docs/built-with-mongoose.pug'] = { title: 'Built with Mongoose' };
+exports['docs/async-await.md'] = { title: 'Using Async/Await with Mongoose', markdown: true };
\ No newline at end of file
diff --git a/website.js b/website.js
index f07c046dbfb..067873360f1 100644
--- a/website.js
+++ b/website.js
@@ -4,6 +4,7 @@ Error.stackTraceLimit = Infinity;
 
 const acquit = require('acquit');
 const fs = require('fs');
+const path = require('path');
 const pug = require('pug');
 const pkg = require('./package');
 const linktype = require('./docs/helpers/linktype');
@@ -65,8 +66,8 @@ require('./docs/splitApiDocs');
 const filemap = Object.assign({}, require('./docs/source'), require('./docs/tutorials'), require('./docs/typescript'));
 const files = Object.keys(filemap);
 
-const wrapMarkdown = md => `
-extends ../layout
+const wrapMarkdown = (md, baseLayout) => `
+extends ${baseLayout}
 
 append style
   link(rel="stylesheet", href="/docs/css/inlinecpc.css")
@@ -114,7 +115,7 @@ function pugify(filename, options, newfile) {
     const lines = contents.split('\n');
     lines.splice(2, 0, cpc);
     contents = lines.join('\n');
-    contents = wrapMarkdown(contents);
+    contents = wrapMarkdown(contents, path.relative(path.dirname(filename), path.join(__dirname, 'docs/layout')));
     newfile = filename.replace('.md', '.html');
   }
 

From 7641be4b900184b2d2eaa9dfc5cd3f3baf547b31 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 19 May 2021 16:57:27 -0400
Subject: [PATCH 2056/2348] 13+mine test failure

---
 test/document.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index debeab2d62d..5fce68a2383 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10256,4 +10256,28 @@ describe('document', function() {
       assert.equal(validatorCallCount, 0);
     });
   });
+  it('support `pathsToSkip` option for `validate()` (feat-10230)', function() {
+    const schema = Schema({
+      name: {
+        type: String,
+        required: true
+      },
+      age: {
+        type: Number,
+        required: true
+      },
+      rank: String
+    });
+    const Model = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = new Model({});
+
+      let err = yield doc.validate({ pathsToSkip: ['age'] }).catch(err => err);
+      assert.deepEqual(Object.keys(err.errors), ['name']);
+
+      err = yield doc.validate({ pathsToSkip: ['name'] }).catch(err => err);
+      assert.deepEqual(Object.keys(err.errors), ['age']);
+    });
+  });
 });

From a5dc57556f00e31731e6154eabb9e843722e319d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 19 May 2021 16:57:48 -0400
Subject: [PATCH 2057/2348] docs: migrate half of pug tutorials to markdown re:
 #10271

---
 docs/browser.md              |  37 +++
 docs/browser.pug             |  69 -----
 docs/built-with-mongoose.md  |  85 ++++++
 docs/built-with-mongoose.pug |  94 ------
 docs/compatibility.md        |  23 ++
 docs/compatibility.pug       |  53 ----
 docs/connections.md          | 529 ++++++++++++++++++++++++++++++++
 docs/connections.pug         | 551 ---------------------------------
 docs/contributing.md         |   3 +
 docs/contributing.pug        |   7 -
 docs/deprecations.md         | 293 ++++++++++++++++++
 docs/deprecations.pug        | 313 -------------------
 docs/enterprise.md           |  71 +++++
 docs/enterprise.pug          | 108 -------
 docs/faq.md                  | 461 ++++++++++++++++++++++++++++
 docs/faq.pug                 | 501 ------------------------------
 docs/further_reading.md      | 208 +++++++++++++
 docs/further_reading.pug     | 229 --------------
 docs/geojson.md              | 160 ++++++++++
 docs/geojson.pug             | 172 -----------
 docs/jest.md                 |  82 +++++
 docs/jest.pug                | 107 -------
 docs/lambda.md               |  85 ++++++
 docs/lambda.pug              | 106 -------
 docs/migrating_to_5.md       | 548 +++++++++++++++++++++++++++++++++
 docs/migrating_to_5.pug      | 572 -----------------------------------
 docs/source/index.js         |  33 +-
 docs/transactions.md         |  76 +++++
 docs/transactions.pug        |  98 ------
 docs/typescript.md           |  93 ++++++
 docs/typescript.pug          | 101 -------
 31 files changed, 2771 insertions(+), 3097 deletions(-)
 create mode 100644 docs/browser.md
 delete mode 100644 docs/browser.pug
 create mode 100644 docs/built-with-mongoose.md
 delete mode 100644 docs/built-with-mongoose.pug
 create mode 100644 docs/compatibility.md
 delete mode 100644 docs/compatibility.pug
 create mode 100644 docs/connections.md
 delete mode 100644 docs/connections.pug
 create mode 100644 docs/contributing.md
 delete mode 100644 docs/contributing.pug
 create mode 100644 docs/deprecations.md
 delete mode 100644 docs/deprecations.pug
 create mode 100644 docs/enterprise.md
 delete mode 100644 docs/enterprise.pug
 create mode 100644 docs/faq.md
 delete mode 100644 docs/faq.pug
 create mode 100644 docs/further_reading.md
 delete mode 100644 docs/further_reading.pug
 create mode 100644 docs/geojson.md
 delete mode 100644 docs/geojson.pug
 create mode 100644 docs/jest.md
 delete mode 100644 docs/jest.pug
 create mode 100644 docs/lambda.md
 delete mode 100644 docs/lambda.pug
 create mode 100644 docs/migrating_to_5.md
 delete mode 100644 docs/migrating_to_5.pug
 create mode 100644 docs/transactions.md
 delete mode 100644 docs/transactions.pug
 create mode 100644 docs/typescript.md
 delete mode 100644 docs/typescript.pug

diff --git a/docs/browser.md b/docs/browser.md
new file mode 100644
index 00000000000..8fc68fa29d4
--- /dev/null
+++ b/docs/browser.md
@@ -0,0 +1,37 @@
+# Mongoose in the Browser
+
+Mongoose supports creating schemas and validating documents in the browser.
+Mongoose's browser library does **not** support saving documents, [queries](http://mongoosejs.com/docs/queries.html), [populate](http://mongoosejs.com/docs/populate.html), [discriminators](http://mongoosejs.com/docs/discriminators.html), or any other Mongoose feature other than schemas and validating documents.
+
+Mongoose has a pre-built bundle of the browser library. If you're bundling your code with [Webpack](https://webpack.js.org/), you should be able to import Mongoose's browser library as shown below if your Webpack `target` is `'web'`:
+
+```javascript
+import mongoose from 'mongoose';
+```
+
+You can use the below syntax to access the Mongoose browser library from Node.js:
+
+```javascript
+// Using `require()`
+const mongoose = require('mongoose/browser');
+
+// Using ES6 imports
+import mongoose from 'mongoose/browser';
+```
+
+<h2 id="usage">Using the Browser Library</h2>
+
+Mongoose's browser library is very limited. The only use case it supports is validating documents as shown below.
+
+```javascript
+import mongoose from 'mongoose';
+
+// Mongoose's browser library does **not** have models. It only supports
+// schemas and documents. The primary use case is validating documents
+// against Mongoose schemas.
+const doc = new mongoose.Document({}, new mongoose.Schema({
+  name: { type: String, required: true }
+}));
+// Prints an error because `name` is required.
+console.log(doc.validateSync());
+```
\ No newline at end of file
diff --git a/docs/browser.pug b/docs/browser.pug
deleted file mode 100644
index d04e3ee6580..00000000000
--- a/docs/browser.pug
+++ /dev/null
@@ -1,69 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet" href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    <h1>Mongoose in the Browser</h1>
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Mongoose supports creating schemas and validating documents in the browser.
-    Mongoose's browser library does **not** support saving documents, [queries](http://mongoosejs.com/docs/queries.html),
-    [populate](http://mongoosejs.com/docs/populate.html),
-    [discriminators](http://mongoosejs.com/docs/discriminators.html),
-    or any other Mongoose feature other than schemas and validating documents.
-
-    Mongoose has a pre-built bundle of the browser library. If you're bundling your code with [Webpack](https://webpack.js.org/),
-    you should be able to import Mongoose's browser library as shown below if your Webpack `target` is `'web'`:
-
-    ```javascript
-    import mongoose from 'mongoose';
-    ```
-
-    You can use the below syntax to access the Mongoose browser library from Node.js:
-
-    ```javascript
-    // Using `require()`
-    const mongoose = require('mongoose/browser');
-
-    // Using ES6 imports
-    import mongoose from 'mongoose/browser';
-    ```
-
-    <ul class="toc">
-      <li><a href="#usage">Using the Browser Library</a></li>
-    </ul>
-
-
-    <h2 id="usage">Using the Browser Library</h2>
-
-    Mongoose's browser library is very limited. The only use case it supports
-    is validating documents as shown below.
-
-    ```javascript
-    import mongoose from 'mongoose';
-
-    // Mongoose's browser library does **not** have models. It only supports
-    // schemas and documents. The primary use case is validating documents
-    // against Mongoose schemas.
-    const doc = new mongoose.Document({}, new mongoose.Schema({
-      name: { type: String, required: true }
-    }));
-    // Prints an error because `name` is required.
-    console.log(doc.validateSync());
-    ```
\ No newline at end of file
diff --git a/docs/built-with-mongoose.md b/docs/built-with-mongoose.md
new file mode 100644
index 00000000000..bbd19d522a1
--- /dev/null
+++ b/docs/built-with-mongoose.md
@@ -0,0 +1,85 @@
+## Built With Mongoose
+
+According to [GitHub](https://github.com/Automattic/mongoose), there are over 870,000 projects that depend on Mongoose.
+Here are a few of our favorite apps that are built with Mongoose.
+
+<div style="position: relative; margin-top: 1em;">
+  <div style="position: absolute; width: 100px; height: 100px">
+    <a href="https://terravera.com">
+      <img src="https://terravera.com/images/avatar.png">
+    </a>
+  </div>
+  <div style="padding-left: 110px; min-height: 100px">
+    <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
+      <a href="https://terravera.com">
+        Terra Vera
+      </a>
+    </h4>
+    Terra Vera produces on-demand antimicrobial chemistry for agriculture and surfaces. Terra Vera's on-site generators convert water, electricity, and a proprietary blend of salts and amino acids into an organic solution that eliminates many common pathogens (like mold, powdery mildew, and viruses), but is safe for plants, people, and pets.
+  </div>
+</div>
+
+<div style="position: relative; margin-top: 1em;">
+  <div style="position: absolute; width: 100px; height: 100px">
+    <a href="https://sixplus.com">
+      <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1452784634/wipgioqzev0omt4ezsay.jpg">
+    </a>
+  </div>
+  <div style="padding-left: 110px; min-height: 100px;">
+    <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://sixplus.com/">SixPlus</a></h3>
+    SixPlus is an online marketplace for corporate event professionals to
+    book private dining spaces in restaurants and hotels across the US.
+    You can book your next company event at venues like <a href="https://sixplus.com/venue/refinery-rooftop-at-refinery-hotel/">Refinery Rooftop</a> or
+    <a href="https://sixplus.com/venue/good-behavior-at-made-hotel/">Good Behavior</a> on SixPlus.
+  </div>
+</div>
+
+<div style="position: relative; margin-top: 1em;">
+  <div style="position: absolute; width: 100px; height: 100px">
+    <a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
+      <img src="https://res-1.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1503059272/h8tzm8hqqabjknhj9cts.png">
+    </a>
+  </div>
+  <div style="padding-left: 110px; min-height: 100px">
+    <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">Payment Ninja</a></h3>
+    Payment Ninja is an online payment gateway that lets you save up to
+    50% on payment processing over processors like PayPal and Stripe.
+  </div>
+</div>
+
+<div style="position: relative; margin-top: 1em;">
+  <div style="position: absolute; width: 100px; height: 100px">
+    <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
+      <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1426108234/rb6qztygayubxme8f4tx.png">
+    </a>
+  </div>
+  <div style="padding-left: 110px; min-height: 100px">
+    <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
+      <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
+        Mixmax
+      </a>
+    </h4>
+    Mixmax is a app that sends engaging emails with instant scheduling, free unlimited email tracking, polls, and surveys right in Gmail.
+  </div>
+</div>
+
+<div style="position: relative; margin-top: 1em;">
+  <div style="position: absolute; width: 100px; height: 100px">
+    <a href="http://builderbook.org/">
+      <img src="https://storage.googleapis.com/builderbook/logo.svg">
+    </a>
+  </div>
+  <div style="padding-left: 110px; min-height: 100px">
+    <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
+      <a href="http://builderbook.org/">
+        Builder Book
+      </a>
+    </h4>
+    Learn how to build a full-stack, production-ready JavaScript web application from scratch. You'll go from 0 lines of code in Chapter 1 to over 10,000 lines of code by Chapter 8.
+  </div>
+</div>
+
+## Add Your Own
+
+Have an app that you built with Mongoose that you want to feature here?
+Let's talk! [DM Mongoose on Twitter](https://twitter.com/mongoosejs).
\ No newline at end of file
diff --git a/docs/built-with-mongoose.pug b/docs/built-with-mongoose.pug
deleted file mode 100644
index 2c30c30dce4..00000000000
--- a/docs/built-with-mongoose.pug
+++ /dev/null
@@ -1,94 +0,0 @@
-extends layout
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Built With Mongoose
-
-    According to [GitHub](https://github.com/Automattic/mongoose), there are
-    over 870,000 projects that depend on Mongoose. Here are a few of
-    our favorite apps that are built with Mongoose.
-
-    <div style="position: relative; margin-top: 1em;">
-      <div style="position: absolute; width: 100px; height: 100px">
-        <a href="https://terravera.com">
-          <img src="https://terravera.com/images/avatar.png">
-        </a>
-      </div>
-      <div style="padding-left: 110px; min-height: 100px">
-        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
-          <a href="https://terravera.com">
-            Terra Vera
-          </a>
-        </h4>
-        Terra Vera produces on-demand antimicrobial chemistry for agriculture and surfaces. Terra Vera's on-site generators convert water, electricity, and a proprietary blend of salts and amino acids into an organic solution that eliminates many common pathogens (like mold, powdery mildew, and viruses), but is safe for plants, people, and pets.
-      </div>
-    </div>
-
-    <div style="position: relative; margin-top: 1em;">
-      <div style="position: absolute; width: 100px; height: 100px">
-        <a href="https://sixplus.com">
-          <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1452784634/wipgioqzev0omt4ezsay.jpg">
-        </a>
-      </div>
-      <div style="padding-left: 110px; min-height: 100px;">
-        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://sixplus.com/">SixPlus</a></h3>
-        SixPlus is an online marketplace for corporate event professionals to
-        book private dining spaces in restaurants and hotels across the US.
-        You can book your next company event at venues like <a href="https://sixplus.com/venue/refinery-rooftop-at-refinery-hotel/">Refinery Rooftop</a> or
-        <a href="https://sixplus.com/venue/good-behavior-at-made-hotel/">Good Behavior</a> on SixPlus.
-      </div>
-    </div>
-
-    <div style="position: relative; margin-top: 1em;">
-      <div style="position: absolute; width: 100px; height: 100px">
-        <a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">
-          <img src="https://res-1.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1503059272/h8tzm8hqqabjknhj9cts.png">
-        </a>
-      </div>
-      <div style="padding-left: 110px; min-height: 100px">
-        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;"><a href="https://payment.ninja/partners/mongoose/?ref=5e2c6ea94e9158a6d2cc2af2">Payment Ninja</a></h3>
-        Payment Ninja is an online payment gateway that lets you save up to
-        50% on payment processing over processors like PayPal and Stripe.
-      </div>
-    </div>
-
-    <div style="position: relative; margin-top: 1em;">
-      <div style="position: absolute; width: 100px; height: 100px">
-        <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
-          <img src="https://res-2.cloudinary.com/crunchbase-production/image/upload/c_lpad,h_120,w_120,f_auto,b_white,q_auto:eco/v1426108234/rb6qztygayubxme8f4tx.png">
-        </a>
-      </div>
-      <div style="padding-left: 110px; min-height: 100px">
-        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
-          <a href="https://mixmax.com/?utm_source=invite&utm_medium=link&utm_campaign=saasquatch&rsCode=VALERIKARPOV&rsShareMedium=DIRECT&rsEngagementMedium=EMBED">
-            Mixmax
-          </a>
-        </h4>
-        Mixmax is a app that sends engaging emails with instant scheduling, free unlimited email tracking, polls, and surveys right in Gmail.
-      </div>
-    </div>
-
-    <div style="position: relative; margin-top: 1em;">
-      <div style="position: absolute; width: 100px; height: 100px">
-        <a href="http://builderbook.org/">
-          <img src="https://storage.googleapis.com/builderbook/logo.svg">
-        </a>
-      </div>
-      <div style="padding-left: 110px; min-height: 100px">
-        <h4 style="margin-top: 0.2em; margin-bottom: 0.25em;">
-          <a href="http://builderbook.org/">
-            Builder Book
-          </a>
-        </h4>
-        Learn how to build a full-stack, production-ready JavaScript web application from scratch. You'll go from 0 lines of code in Chapter 1 to over 10,000 lines of code by Chapter 8.
-      </div>
-    </div>
-
-    ## Add Your Own
-
-    Have an app that you built with Mongoose that you want to feature here?
-    Let's talk! [DM Mongoose on Twitter](https://twitter.com/mongoosejs).
diff --git a/docs/compatibility.md b/docs/compatibility.md
new file mode 100644
index 00000000000..5e4919f592d
--- /dev/null
+++ b/docs/compatibility.md
@@ -0,0 +1,23 @@
+# MongoDB Server Version Compatibility
+
+Mongoose relies on the [MongoDB Node.js Driver](http://mongodb.github.io/node-mongodb-native/) to talk to MongoDB. 
+You can refer to [this table](https://docs.mongodb.com/ecosystem/drivers/driver-compatibility-reference/#node-js-driver-compatibility) for up-to-date information as to which version of the MongoDB driver supports which version of MongoDB.
+
+Below are the [semver](http://semver.org/) ranges representing which versions of mongoose are compatible with the listed versions of MongoDB server.
+
+* MongoDB Server 2.4.x: mongoose `^3.8` or `4.x`
+* MongoDB Server 2.6.x: mongoose `^3.8.8` or `4.x`
+* MongoDB Server 3.0.x: mongoose `^3.8.22`, `4.x`, or `5.x`
+* MongoDB Server 3.2.x: mongoose `^4.3.0` or `5.x`
+* MongoDB Server 3.4.x: mongoose `^4.7.3` or `5.x`
+* MongoDB Server 3.6.x: mongoose `5.x`
+* MongoDB Server 4.0.x: mongoose `^5.2.0`
+* MongoDB Server 4.2.x: mongoose `^5.7.0`
+* MongoDB Server 4.4.x: mongoose `^5.10.0`
+
+Note that Mongoose 5.x dropped support for all versions of MongoDB before 3.0.0. If you need to use MongoDB 2.6 or older, use Mongoose 4.x.
+
+## Further Reading
+
+Are you on Mongoose 3.x and looking to migrate to 4.x? Check out [_Moving Forward with Mongoose.js_ on Pluralsight](https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoosejs-moving-forward%2Ftable-of-contents).
+This video course walks you through the new features and backwards breaking changes in Mongoose 4, so you can upgrade with confidence.
\ No newline at end of file
diff --git a/docs/compatibility.pug b/docs/compatibility.pug
deleted file mode 100644
index 1ce8f946aec..00000000000
--- a/docs/compatibility.pug
+++ /dev/null
@@ -1,53 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## MongoDB Server Version Compatibility
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Mongoose relies on the [MongoDB Node.js Driver](http://mongodb.github.io/node-mongodb-native/)
-    to talk to MongoDB. You can refer to
-    [this table](https://docs.mongodb.com/ecosystem/drivers/driver-compatibility-reference/#node-js-driver-compatibility)
-    for up-to-date information as to which version of the MongoDB driver
-    supports which version of MongoDB.
-
-    Below are the [semver](http://semver.org/) ranges representing which
-    versions of mongoose are compatible with the listed versions of MongoDB
-    server.
-
-    * MongoDB Server 2.4.x: mongoose `^3.8` or `4.x`
-    * MongoDB Server 2.6.x: mongoose `^3.8.8` or `4.x`
-    * MongoDB Server 3.0.x: mongoose `^3.8.22`, `4.x`, or `5.x`
-    * MongoDB Server 3.2.x: mongoose `^4.3.0` or `5.x`
-    * MongoDB Server 3.4.x: mongoose `^4.7.3` or `5.x`
-    * MongoDB Server 3.6.x: mongoose `5.x`
-    * MongoDB Server 4.0.x: mongoose `^5.2.0`
-    * MongoDB Server 4.2.x: mongoose `^5.7.0`
-    * MongoDB Server 4.4.x: mongoose `^5.10.0`
-
-    Note that Mongoose 5.x dropped support for all versions of MongoDB before
-    3.0.0. If you need to use MongoDB 2.6 or older, use Mongoose 4.x.
-
-    ## Further Reading
-
-    Are you on Mongoose 3.x and looking to migrate to 4.x? Check out
-    [_Moving Forward with Mongoose.js_ on Pluralsight](https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoosejs-moving-forward%2Ftable-of-contents).
-    This video course walks you through the new features and backwards breaking
-    changes in Mongoose 4, so you can upgrade with confidence.
diff --git a/docs/connections.md b/docs/connections.md
new file mode 100644
index 00000000000..c77239df486
--- /dev/null
+++ b/docs/connections.md
@@ -0,0 +1,529 @@
+## Connections
+
+You can connect to MongoDB with the `mongoose.connect()` method.
+
+```javascript
+mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
+```
+
+This is the minimum needed to connect the `myapp` database running locally
+on the default port (27017). If connecting fails on your machine, try using
+`127.0.0.1` instead of `localhost`.
+
+You can also specify several more parameters in the `uri`:
+
+```javascript
+mongoose.connect('mongodb://username:password@host:port/database?options...', {useNewUrlParser: true});
+```
+
+See the [mongodb connection string spec](http://docs.mongodb.org/manual/reference/connection-string/) for more detail.
+
+<ul class="toc">
+  <li><a href="#buffering">Buffering</a></li>
+  <li><a href="#error-handling">Error Handling</a></li>
+  <li><a href="#options">Options</a></li>
+  <li><a href="#connection-string-options">Connection String Options</a></li>
+  <li><a href="#connection-events">Connection Events</a></li>
+  <li><a href="#keepAlive">A note about keepAlive</a></li>
+  <li><a href="#server-selection">Server Selection</a></li>
+  <li><a href="#replicaset_connections">Replica Set Connections</a></li>
+  <li><a href="#replicaset-hostnames">Replica Set Host Names</a></li>
+  <li><a href="#mongos_connections">Multi-mongos support</a></li>
+  <li><a href="#multiple_connections">Multiple connections</a></li>
+  <li><a href="#connection_pools">Connection Pools</a></li>
+  <li><a href="#v5-changes">Option Changes in v5.x</a></li>
+</ul>
+
+<h3 id="buffering"><a href="#buffering">Operation Buffering</a></h3>
+
+Mongoose lets you start using your models immediately, without waiting for
+mongoose to establish a connection to MongoDB.
+
+```javascript
+mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
+const MyModel = mongoose.model('Test', new Schema({ name: String }));
+// Works
+MyModel.findOne(function(error, result) { /* ... */ });
+```
+
+That's because mongoose buffers model function calls internally. This
+buffering is convenient, but also a common source of confusion. Mongoose
+will *not* throw any errors by default if you use a model without
+connecting.
+
+```javascript
+const MyModel = mongoose.model('Test', new Schema({ name: String }));
+// Will just hang until mongoose successfully connects
+MyModel.findOne(function(error, result) { /* ... */ });
+
+setTimeout(function() {
+  mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
+}, 60000);
+```
+
+To disable buffering, turn off the [`bufferCommands` option on your schema](./guide.html#bufferCommands).
+If you have `bufferCommands` on and your connection is hanging, try turning
+`bufferCommands` off to see if you haven't opened a connection properly.
+You can also disable `bufferCommands` globally:
+
+```javascript
+mongoose.set('bufferCommands', false);
+```
+
+Note that buffering is also responsible for waiting until Mongoose
+creates collections if you use the [`autoCreate` option](/docs/guide.html#autoCreate).
+If you disable buffering, you should also disable the `autoCreate`
+option and use [`createCollection()`](/docs/api/model.html#model_Model.createCollection)
+to create [capped collections](/docs/guide.html#capped) or
+[collections with collations](/docs/guide.html#collation).
+
+```javascript
+const schema = new Schema({
+  name: String
+}, {
+  capped: { size: 1024 },
+  bufferCommands: false,
+  autoCreate: false // disable `autoCreate` since `bufferCommands` is false
+});
+
+const Model = mongoose.model('Test', schema);
+// Explicitly create the collection before using it
+// so the collection is capped.
+await Model.createCollection();
+```
+
+<h3 id="error-handling"><a href="#error-handling">Error Handling</a></h3>
+
+There are two classes of errors that can occur with a Mongoose connection.
+
+- Error on initial connection. If initial connection fails, Mongoose will emit an 'error' event and the promise `mongoose.connect()` returns will reject. However, Mongoose will **not** automatically try to reconnect.
+- Error after initial connection was established. Mongoose will attempt to reconnect, and it will emit an 'error' event.
+
+To handle initial connection errors, you should use `.catch()` or `try/catch` with async/await.
+
+```javascript
+mongoose.connect('mongodb://localhost:27017/test', { useNewUrlParser: true }).
+  catch(error => handleError(error));
+
+// Or:
+try {
+  await mongoose.connect('mongodb://localhost:27017/test', { useNewUrlParser: true });
+} catch (error) {
+  handleError(error);
+}
+```
+
+To handle errors after initial connection was established, you should
+listen for error events on the connection. However, you still need to
+handle initial connection errors as shown above.
+
+```javascript
+mongoose.connection.on('error', err => {
+  logError(err);
+});
+```
+
+Note that Mongoose does not necessarily emit an 'error' event if it loses connectivity to MongoDB. You should
+listen to the `disconnected` event to report when Mongoose is disconnected from MongoDB.
+
+<h3 id="options"><a href="#options">Options</a></h3>
+
+The `connect` method also accepts an `options` object which will be passed
+on to the underlying MongoDB driver.
+
+```javascript
+mongoose.connect(uri, options);
+```
+
+A full list of options can be found on the [MongoDB Node.js driver docs for `connect()`](http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect).
+Mongoose passes options to the driver without modification, modulo a few
+exceptions that are explained below.
+
+* `bufferCommands`    - This is a mongoose-specific option (not passed to the MongoDB driver) that disables [Mongoose's buffering mechanism](http://mongoosejs.com/docs/faq.html#callback_never_executes)
+* `user`/`pass`       - The username and password for authentication. These options are Mongoose-specific, they are equivalent to the MongoDB driver's `auth.user` and `auth.password` options.
+* `autoIndex`         - By default, mongoose will automatically build indexes defined in your schema when it connects. This is great for development, but not ideal for large production deployments, because index builds can cause performance degradation. If you set `autoIndex` to false, mongoose will not automatically build indexes for **any** model associated with this connection.
+* `dbName`            - Specifies which database to connect to and overrides any database specified in the connection string. This is useful if you are unable to specify a default database in the connection string like with [some `mongodb+srv` syntax connections](https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626).
+
+Below are some of the options that are important for tuning Mongoose.
+
+* `useNewUrlParser`   - The underlying MongoDB driver has deprecated their current [connection string](https://docs.mongodb.com/manual/reference/connection-string/) parser. Because this is a major change, they added the `useNewUrlParser` flag to allow users to fall back to the old parser if they find a bug in the new parser. You should set `useNewUrlParser: true` unless that prevents you from connecting. Note that if you specify `useNewUrlParser: true`, you **must** specify a port in your connection string, like `mongodb://localhost:27017/dbname`. The new url parser does _not_ support connection strings that do not have a port, like `mongodb://localhost/dbname`.
+* `useCreateIndex`    - False by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
+* `useFindAndModify`  - True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
+* `useUnifiedTopology`- False by default. Set to `true` to opt in to using [the MongoDB driver's new connection management engine](/docs/deprecations.html#useunifiedtopology). You should set this option to `true`, except for the unlikely case that it prevents you from maintaining a stable connection.
+* `promiseLibrary`    - Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
+* `poolSize`          - The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
+* `socketTimeoutMS`   - How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
+* `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
+* `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
+
+The following options are important for tuning Mongoose only if you are
+running **without** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
+
+* `autoReconnect`     - The underlying MongoDB driver will automatically try to reconnect when it loses connection to MongoDB. Unless you are an extremely advanced user that wants to manage their own connection pool, do **not** set this option to `false`.
+* `reconnectTries`    - If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
+* `reconnectInterval` - See `reconnectTries`
+* `bufferMaxEntries`  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
+* `connectTimeoutMS`  - How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
+
+The following options are important for tuning Mongoose only if you are
+running **with** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
+
+* `serverSelectionTimeoutMS` - With `useUnifiedTopology`, the MongoDB driver will try to find a server to send any given operation to, and keep retrying for `serverSelectionTimeoutMS` milliseconds. If not set, the MongoDB driver defaults to using `30000` (30 seconds).
+* `heartbeatFrequencyMS` - With `useUnifiedTopology`, the MongoDB driver sends a heartbeat every `heartbeatFrequencyMS` to check on the status of the connection. A heartbeat is subject to `serverSelectionTimeoutMS`, so the MongoDB driver will retry failed heartbeats for up to 30 seconds by default. Mongoose only emits a `'disconnected'` event after a heartbeat has failed, so you may want to decrease this setting to reduce the time between when your server goes down and when Mongoose emits `'disconnected'`. We recommend you do **not** set this setting below 1000, too many heartbeats can lead to performance degradation.
+
+The `serverSelectionTimeoutMS` option also handles how long `mongoose.connect()` will
+retry initial connection before erroring out. With `useUnifiedTopology`, `mongoose.connect()`
+will retry for 30 seconds by default (default `serverSelectionTimeoutMS`) before
+erroring out. To get faster feedback on failed operations, you can reduce `serverSelectionTimeoutMS`
+to 5000 as shown below.
+
+Example:
+
+```javascript
+const options = {
+  useNewUrlParser: true,
+  useUnifiedTopology: true,
+  useCreateIndex: true,
+  useFindAndModify: false,
+  autoIndex: false, // Don't build indexes
+  poolSize: 10, // Maintain up to 10 socket connections
+  serverSelectionTimeoutMS: 5000, // Keep trying to send operations for 5 seconds
+  socketTimeoutMS: 45000, // Close sockets after 45 seconds of inactivity
+  family: 4 // Use IPv4, skip trying IPv6
+};
+mongoose.connect(uri, options);
+```
+
+See [this page](http://mongodb.github.io/node-mongodb-native/3.1/reference/faq/) for more information about `connectTimeoutMS` and `socketTimeoutMS`
+
+<h3 id="callback"><a href="#callback">Callback</a></h3>
+
+The `connect()` function also accepts a callback parameter and returns a
+[promise](./promises.html).
+
+```javascript
+mongoose.connect(uri, options, function(error) {
+  // Check error in initial connection. There is no 2nd param to the callback.
+});
+
+// Or using promises
+mongoose.connect(uri, options).then(
+  () => { /** ready to use. The `mongoose.connect()` promise resolves to mongoose instance. */ },
+  err => { /** handle initial connection error */ }
+);
+```
+
+<h3 id="connection-string-options"><a href="#connection-string-options">Connection String Options</a></h3>
+
+You can also specify driver options in your connection string as
+[parameters in the query string](https://en.wikipedia.org/wiki/Query_string)
+portion of the URI. This only applies to options passed to the MongoDB
+driver. You **can't** set Mongoose-specific options like `bufferCommands`
+in the query string.
+
+```javascript
+mongoose.connect('mongodb://localhost:27017/test?connectTimeoutMS=1000&bufferCommands=false&authSource=otherdb');
+// The above is equivalent to:
+mongoose.connect('mongodb://localhost:27017/test', {
+  connectTimeoutMS: 1000
+  // Note that mongoose will **not** pull `bufferCommands` from the query string
+});
+```
+
+The disadvantage of putting options in the query string is that query
+string options are harder to read. The advantage is that you only need a
+single configuration option, the URI, rather than separate options for
+`socketTimeoutMS`, `connectTimeoutMS`, etc. Best practice is to put options
+that likely differ between development and production, like `replicaSet`
+or `ssl`, in the connection string, and options that should remain constant,
+like `connectTimeoutMS` or `poolSize`, in the options object.
+
+The MongoDB docs have a full list of
+[supported connection string options](https://docs.mongodb.com/manual/reference/connection-string/).
+Below are some options that are often useful to set in the connection string because they
+are closely associated with the hostname and authentication information.
+
+* `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
+* `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
+
+<h3 id="connection-events"><a href="#connection-events">Connection Events</a></h3>
+
+Connections inherit from [Node.js' `EventEmitter` class](https://nodejs.org/api/events.html#events_class_eventemitter),
+and emit events when something happens to the connection, like losing
+connectivity to the MongoDB server. Below is a list of events that a
+connection may emit.
+
+* `connecting`: Emitted when Mongoose starts making its initial connection to the MongoDB server
+* `connected`: Emitted when Mongoose successfully makes its initial connection to the MongoDB server, or when Mongoose reconnects after losing connectivity.
+* `open`: Equivalent to `connected`
+* `disconnecting`: Your app called [`Connection#close()`](api.html#connection_Connection-close) to disconnect from MongoDB
+* `disconnected`: Emitted when Mongoose lost connection to the MongoDB server. This event may be due to your code explicitly closing the connection, the database server crashing, or network connectivity issues.
+* `close`: Emitted after [`Connection#close()`](api.html#connection_Connection-close) successfully closes the connection. If you call `conn.close()`, you'll get both a 'disconnected' event and a 'close' event.
+* `reconnected`: Emitted if Mongoose lost connectivity to MongoDB and successfully reconnected. Mongoose attempts to [automatically reconnect](https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html) when it loses connection to the database.
+* `error`: Emitted if an error occurs on a connection, like a `parseError` due to malformed data or a payload larger than [16MB](https://docs.mongodb.com/manual/reference/limits/#BSON-Document-Size).
+* `fullsetup`: Emitted when you're connecting to a replica set and Mongoose has successfully connected to the primary and at least one secondary.
+* `all`: Emitted when you're connecting to a replica set and Mongoose has successfully connected to all servers specified in your connection string.
+* `reconnectFailed`: Emitted when you're connected to a standalone server and Mongoose has run out of [`reconnectTries`](https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html#handling-single-server-outages). The [MongoDB driver](http://npmjs.com/package/mongodb) will no longer attempt to reconnect after this event is emitted. This event will never be emitted if you're connected to a replica set.
+
+When you're connecting to a single MongoDB server (a "standalone"), Mongoose will emit 'disconnected' if it gets
+disconnected from the standalone server, and 'connected' if it successfully connects to the standalone. In a
+replica set with `useUnifiedTopology = true`, Mongoose will emit 'disconnected' if it loses connectivity to
+_every_ server in the replica set, and 'connected' if it manages to reconnect to at least one server in the replica set.
+
+<h3 id="keepAlive"><a href="#keepAlive">A note about keepAlive</a></h3>
+
+For long running applications, it is often prudent to enable `keepAlive`
+with a number of milliseconds. Without it, after some period of time
+you may start to see `"connection closed"` errors for what seems like
+no reason. If so, after
+[reading this](http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/overview.html),
+you may decide to enable `keepAlive`:
+
+```javascript
+mongoose.connect(uri, { keepAlive: true, keepAliveInitialDelay: 300000 });
+```
+
+`keepAliveInitialDelay` is the number of milliseconds to wait before initiating `keepAlive` on the socket.
+`keepAlive` is true by default since mongoose 5.2.0.
+
+<h3 id="replicaset_connections"><a href="#replicaset_connections">Replica Set Connections</a></h3>
+
+To connect to a replica set you pass a comma delimited list of hosts to
+connect to rather than a single host.
+
+```javascript
+mongoose.connect('mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]' [, options]);
+```
+
+For example:
+
+```javascript
+mongoose.connect('mongodb://user:pw@host1.com:27017,host2.com:27017,host3.com:27017/testdb');
+```
+
+To connect to a single node replica set, specify the `replicaSet` option.
+
+```javascript
+mongoose.connect('mongodb://host1:port1/?replicaSet=rsName');
+```
+
+<h3 id="server-selection"><a href="#server-selection">Server Selection</a></h3>
+
+If you enable the `useUnifiedTopology` option, the underlying MongoDB driver
+will use [server selection](https://github.com/mongodb/specifications/blob/master/source/server-selection/server-selection.rst)
+to connect to MongoDB and send operations to MongoDB. If the MongoDB
+driver can't find a server to send an operation to after `serverSelectionTimeoutMS`,
+you'll get the below error:
+
+```
+MongoTimeoutError: Server selection timed out after 30000 ms
+```
+
+You can configure the timeout using the `serverSelectionTimeoutMS` option
+to `mongoose.connect()`:
+
+```javascript
+mongoose.connect(uri, {
+  useNewUrlParser: true,
+  useUnifiedTopology: true,
+  serverSelectionTimeoutMS: 5000 // Timeout after 5s instead of 30s
+});
+```
+
+A `MongoTimeoutError` has a `reason` property that explains why
+server selection timed out. For example, if you're connecting to
+a standalone server with an incorrect password, `reason`
+will contain an "Authentication failed" error.
+
+```javascript
+const mongoose = require('mongoose');
+
+const uri = 'mongodb+srv://username:badpw@cluster0-OMITTED.mongodb.net/' +
+  'test?retryWrites=true&w=majority';
+// Prints "MongoError: bad auth Authentication failed."
+mongoose.connect(uri, {
+  useNewUrlParser: true,
+  useUnifiedTopology: true,
+  serverSelectionTimeoutMS: 5000
+}).catch(err => console.log(err.reason));
+```
+
+<h3 id="replicaset-hostnames"><a href="#replicaset-hostnames">Replica Set Host Names</a></h3>
+
+MongoDB replica sets rely on being able to reliably figure out the domain name
+for each member. On Linux and OSX, the MongoDB server uses the output of the
+[`hostname` command](https://linux.die.net/man/1/hostname) to figure out the
+domain name to report to the replica set. This can cause confusing errors
+if you're connecting to a remote MongoDB replica set running on a machine that
+reports its `hostname` as `localhost`:
+
+```
+// Can get this error even if your connection string doesn't include
+// `localhost` if `rs.conf()` reports that one replica set member has
+// `localhost` as its host name.
+failed to connect to server [localhost:27017] on first connect
+```
+
+If you're experiencing a similar error, connect to the replica set using the
+`mongo` shell and run the
+[`rs.conf()`](https://docs.mongodb.com/manual/reference/method/rs.conf/) command to check the host names of each replica set member. Follow
+[this page's instructions to change a replica set member's host name](https://docs.mongodb.com/manual/tutorial/change-hostnames-in-a-replica-set/#change-hostnames-while-maintaining-replica-set-availability).
+
+<h3 id="mongos_connections"><a href="#mongos_connections">Multi-mongos support</a></h3>
+
+You can also connect to multiple [mongos](https://docs.mongodb.com/manual/reference/program/mongos/) instances
+for high availability in a sharded cluster. You do
+[not need to pass any special options to connect to multiple mongos](http://mongodb.github.io/node-mongodb-native/3.0/tutorials/connect/#connect-to-sharded-cluster) in mongoose 5.x.
+
+```javascript
+// Connect to 2 mongos servers
+mongoose.connect('mongodb://mongosA:27501,mongosB:27501', cb);
+```
+
+<h3 id="multiple_connections"><a href="#multiple_connections">Multiple connections</a></h3>
+
+So far we've seen how to connect to MongoDB using Mongoose's default
+connection. Mongoose creates a _default connection_ when you call `mongoose.connect()`.
+You can access the default connection using `mongoose.connection`.
+
+You may need multiple connections to MongoDB for several reasons.
+One reason is if you have multiple databases or multiple MongoDB clusters.
+Another reason is to work around [slow trains](https://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
+The `mongoose.createConnection()` function takes the same arguments as
+`mongoose.connect()` and returns a new connection.
+
+```javascript
+const conn = mongoose.createConnection('mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]', options);
+```
+
+This [connection](./api.html#connection_Connection) object is then used to
+create and retrieve [models](./api.html#model_Model). Models are
+**always** scoped to a single connection.
+
+```javascript
+const UserModel = conn.model('User', userSchema);
+```
+
+If you use multiple connections, you should make sure you export schemas,
+**not** models. Exporting a model from a file is called the _export model pattern_.
+The export model pattern is limited because you can only use one connection.
+
+```javascript
+const userSchema = new Schema({ name: String, email: String });
+
+// The alternative to the export model pattern is the export schema pattern.
+module.exports = userSchema;
+
+// Because if you export a model as shown below, the model will be scoped
+// to Mongoose's default connection.
+// module.exports = mongoose.model('User', userSchema);
+```
+
+If you use the export schema pattern, you still need to create models
+somewhere. There are two common patterns. First is to export a connection
+and register the models on the connection in the file:
+
+```javascript
+// connections/fast.js
+const mongoose = require('mongoose');
+
+const conn = mongoose.createConnection(process.env.MONGODB_URI);
+conn.model('User', require('../schemas/user'));
+
+module.exports = conn;
+
+// connections/slow.js
+const mongoose = require('mongoose');
+
+const conn = mongoose.createConnection(process.env.MONGODB_URI);
+conn.model('User', require('../schemas/user'));
+conn.model('PageView', require('../schemas/pageView'));
+
+module.exports = conn;
+```
+
+Another alternative is to register connections with a dependency injector
+or another [inversion of control (IOC) pattern](https://thecodebarbarian.com/using-ramda-as-a-dependency-injector).
+
+```javascript
+const mongoose = require('mongoose');
+
+module.exports = function connectionFactory() {
+  const conn = mongoose.createConnection(process.env.MONGODB_URI);
+
+  conn.model('User', require('../schemas/user'));
+  conn.model('PageView', require('../schemas/pageView'));
+
+  return conn; 
+};
+```
+
+<h3 id="connection_pools"><a href="#connection_pools">Connection Pools</a></h3>
+
+Each `connection`, whether created with `mongoose.connect` or
+`mongoose.createConnection` are all backed by an internal configurable
+connection pool defaulting to a maximum size of 5. Adjust the pool size
+using your connection options:
+
+```javascript
+// With object options
+mongoose.createConnection(uri, { poolSize: 4 });
+
+const uri = 'mongodb://localhost:27017/test?poolSize=4';
+mongoose.createConnection(uri);
+```
+
+<h3 id="v5-changes"><a href="#v5-changes">Option Changes in v5.x</a></h3>
+
+You may see the following deprecation warning if upgrading from 4.x to 5.x
+and you didn't use the `useMongoClient` option in 4.x:
+
+```
+the server/replset/mongos options are deprecated, all their options are supported at the top level of the options object
+```
+
+In older version of the MongoDB driver you had to specify distinct options
+for server connections, replica set connections, and mongos connections:
+
+```javascript
+mongoose.connect(myUri, {
+  server: {
+    socketOptions: {
+      socketTimeoutMS: 0,
+      keepAlive: true
+    },
+    reconnectTries: 30
+  },
+  replset: {
+    socketOptions: {
+      socketTimeoutMS: 0,
+      keepAlive: true
+    },
+    reconnectTries: 30
+  },
+  mongos: {
+    socketOptions: {
+      socketTimeoutMS: 0,
+      keepAlive: true
+    },
+    reconnectTries: 30
+  }
+});
+```
+
+In mongoose v5.x you can instead declare these options at the top level,
+without all that extra nesting.
+[Here's the list of all supported options](http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html).
+
+```javascript
+// Equivalent to the above code
+mongoose.connect(myUri, {
+  socketTimeoutMS: 0,
+  keepAlive: true,
+  reconnectTries: 30
+});
+```
+
+<h3 id="next">Next Up</h3>
+
+Now that we've covered connections, let's take a look at [models](/docs/models.html).
\ No newline at end of file
diff --git a/docs/connections.pug b/docs/connections.pug
deleted file mode 100644
index 4a9962b4cd1..00000000000
--- a/docs/connections.pug
+++ /dev/null
@@ -1,551 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    <h2><a href="#connections">Connections</a></h2>
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    You can connect to MongoDB with the `mongoose.connect()` method.
-
-    ```javascript
-    mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
-    ```
-
-    This is the minimum needed to connect the `myapp` database running locally
-    on the default port (27017). If connecting fails on your machine, try using
-    `127.0.0.1` instead of `localhost`.
-
-    You can also specify several more parameters in the `uri`:
-
-    ```javascript
-    mongoose.connect('mongodb://username:password@host:port/database?options...', {useNewUrlParser: true});
-    ```
-
-    See the [mongodb connection string spec](http://docs.mongodb.org/manual/reference/connection-string/) for more detail.
-
-    <ul class="toc">
-      <li><a href="#buffering">Buffering</a></li>
-      <li><a href="#error-handling">Error Handling</a></li>
-      <li><a href="#options">Options</a></li>
-      <li><a href="#connection-string-options">Connection String Options</a></li>
-      <li><a href="#connection-events">Connection Events</a></li>
-      <li><a href="#keepAlive">A note about keepAlive</a></li>
-      <li><a href="#server-selection">Server Selection</a></li>
-      <li><a href="#replicaset_connections">Replica Set Connections</a></li>
-      <li><a href="#replicaset-hostnames">Replica Set Host Names</a></li>
-      <li><a href="#mongos_connections">Multi-mongos support</a></li>
-      <li><a href="#multiple_connections">Multiple connections</a></li>
-      <li><a href="#connection_pools">Connection Pools</a></li>
-      <li><a href="#v5-changes">Option Changes in v5.x</a></li>
-    </ul>
-
-    <h3 id="buffering"><a href="#buffering">Operation Buffering</a></h3>
-
-    Mongoose lets you start using your models immediately, without waiting for
-    mongoose to establish a connection to MongoDB.
-
-    ```javascript
-    mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
-    const MyModel = mongoose.model('Test', new Schema({ name: String }));
-    // Works
-    MyModel.findOne(function(error, result) { /* ... */ });
-    ```
-
-    That's because mongoose buffers model function calls internally. This
-    buffering is convenient, but also a common source of confusion. Mongoose
-    will *not* throw any errors by default if you use a model without
-    connecting.
-
-    ```javascript
-    const MyModel = mongoose.model('Test', new Schema({ name: String }));
-    // Will just hang until mongoose successfully connects
-    MyModel.findOne(function(error, result) { /* ... */ });
-
-    setTimeout(function() {
-      mongoose.connect('mongodb://localhost:27017/myapp', {useNewUrlParser: true});
-    }, 60000);
-    ```
-
-    To disable buffering, turn off the [`bufferCommands` option on your schema](./guide.html#bufferCommands).
-    If you have `bufferCommands` on and your connection is hanging, try turning
-    `bufferCommands` off to see if you haven't opened a connection properly.
-    You can also disable `bufferCommands` globally:
-
-    ```javascript
-    mongoose.set('bufferCommands', false);
-    ```
-
-    Note that buffering is also responsible for waiting until Mongoose
-    creates collections if you use the [`autoCreate` option](/docs/guide.html#autoCreate).
-    If you disable buffering, you should also disable the `autoCreate`
-    option and use [`createCollection()`](/docs/api/model.html#model_Model.createCollection)
-    to create [capped collections](/docs/guide.html#capped) or
-    [collections with collations](/docs/guide.html#collation).
-
-    ```javascript
-    const schema = new Schema({
-      name: String
-    }, {
-      capped: { size: 1024 },
-      bufferCommands: false,
-      autoCreate: false // disable `autoCreate` since `bufferCommands` is false
-    });
-
-    const Model = mongoose.model('Test', schema);
-    // Explicitly create the collection before using it
-    // so the collection is capped.
-    await Model.createCollection();
-    ```
-
-    <h3 id="error-handling"><a href="#error-handling">Error Handling</a></h3>
-
-    There are two classes of errors that can occur with a Mongoose connection.
-
-    - Error on initial connection. If initial connection fails, Mongoose will emit an 'error' event and the promise `mongoose.connect()` returns will reject. However, Mongoose will **not** automatically try to reconnect.
-    - Error after initial connection was established. Mongoose will attempt to reconnect, and it will emit an 'error' event.
-
-    To handle initial connection errors, you should use `.catch()` or `try/catch` with async/await.
-    
-    ```javascript
-    mongoose.connect('mongodb://localhost:27017/test', { useNewUrlParser: true }).
-      catch(error => handleError(error));
-
-    // Or:
-    try {
-      await mongoose.connect('mongodb://localhost:27017/test', { useNewUrlParser: true });
-    } catch (error) {
-      handleError(error);
-    }
-    ```
-
-    To handle errors after initial connection was established, you should
-    listen for error events on the connection. However, you still need to
-    handle initial connection errors as shown above.
-
-    ```javascript
-    mongoose.connection.on('error', err => {
-      logError(err);
-    });
-    ```
-
-    Note that Mongoose does not necessarily emit an 'error' event if it loses connectivity to MongoDB. You should
-    listen to the `disconnected` event to report when Mongoose is disconnected from MongoDB.
-
-    <h3 id="options"><a href="#options">Options</a></h3>
-
-    The `connect` method also accepts an `options` object which will be passed
-    on to the underlying MongoDB driver.
-
-    ```javascript
-    mongoose.connect(uri, options);
-    ```
-
-    A full list of options can be found on the [MongoDB Node.js driver docs for `connect()`](http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect).
-    Mongoose passes options to the driver without modification, modulo a few
-    exceptions that are explained below.
-
-    * `bufferCommands`    - This is a mongoose-specific option (not passed to the MongoDB driver) that disables [Mongoose's buffering mechanism](http://mongoosejs.com/docs/faq.html#callback_never_executes)
-    * `user`/`pass`       - The username and password for authentication. These options are Mongoose-specific, they are equivalent to the MongoDB driver's `auth.user` and `auth.password` options.
-    * `autoIndex`         - By default, mongoose will automatically build indexes defined in your schema when it connects. This is great for development, but not ideal for large production deployments, because index builds can cause performance degradation. If you set `autoIndex` to false, mongoose will not automatically build indexes for **any** model associated with this connection.
-    * `dbName`            - Specifies which database to connect to and overrides any database specified in the connection string. This is useful if you are unable to specify a default database in the connection string like with [some `mongodb+srv` syntax connections](https://stackoverflow.com/questions/48917591/fail-to-connect-mongoose-to-atlas/48917626#48917626).
-
-    Below are some of the options that are important for tuning Mongoose.
-
-    * `useNewUrlParser`   - The underlying MongoDB driver has deprecated their current [connection string](https://docs.mongodb.com/manual/reference/connection-string/) parser. Because this is a major change, they added the `useNewUrlParser` flag to allow users to fall back to the old parser if they find a bug in the new parser. You should set `useNewUrlParser: true` unless that prevents you from connecting. Note that if you specify `useNewUrlParser: true`, you **must** specify a port in your connection string, like `mongodb://localhost:27017/dbname`. The new url parser does _not_ support connection strings that do not have a port, like `mongodb://localhost/dbname`.
-    * `useCreateIndex`    - False by default. Set to `true` to make Mongoose's default index build use `createIndex()` instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
-    * `useFindAndModify`  - True by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()` use native `findOneAndUpdate()` rather than `findAndModify()`.
-    * `useUnifiedTopology`- False by default. Set to `true` to opt in to using [the MongoDB driver's new connection management engine](/docs/deprecations.html#useunifiedtopology). You should set this option to `true`, except for the unlikely case that it prevents you from maintaining a stable connection.
-    * `promiseLibrary`    - Sets the [underlying driver's promise library](http://mongodb.github.io/node-mongodb-native/3.1/api/MongoClient.html).
-    * `poolSize`          - The maximum number of sockets the MongoDB driver will keep open for this connection. By default, `poolSize` is 5. Keep in mind that, as of MongoDB 3.4, MongoDB only allows one operation per socket at a time, so you may want to increase this if you find you have a few slow queries that are blocking faster queries from proceeding. See [Slow Trains in MongoDB and Node.js](http://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
-    * `socketTimeoutMS`   - How long the MongoDB driver will wait before killing a socket due to inactivity _after initial connection_. A socket may be inactive because of either no activity or a long-running operation. This is set to `30000` by default, you should set this to 2-3x your longest running operation if you expect some of your database operations to run longer than 20 seconds. This option is passed to [Node.js `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback) after the MongoDB driver successfully completes.
-    * `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
-    * `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
-
-    The following options are important for tuning Mongoose only if you are
-    running **without** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
-
-    * `autoReconnect`     - The underlying MongoDB driver will automatically try to reconnect when it loses connection to MongoDB. Unless you are an extremely advanced user that wants to manage their own connection pool, do **not** set this option to `false`.
-    * `reconnectTries`    - If you're connected to a single server or mongos proxy (as opposed to a replica set), the MongoDB driver will try to reconnect every `reconnectInterval` milliseconds for `reconnectTries` times, and give up afterward. When the driver gives up, the mongoose connection emits a `reconnectFailed` event. This option does nothing for replica set connections.
-    * `reconnectInterval` - See `reconnectTries`
-    * `bufferMaxEntries`  - The MongoDB driver also has its own buffering mechanism that kicks in when the driver is disconnected. Set this option to 0 and set `bufferCommands` to `false` on your schemas if you want your database operations to fail immediately when the driver is not connected, as opposed to waiting for reconnection.
-    * `connectTimeoutMS`  - How long the MongoDB driver will wait before killing a socket due to inactivity _during initial connection_. Defaults to 30000. This option is passed transparently to [Node.js' `socket#setTimeout()` function](https://nodejs.org/api/net.html#net_socket_settimeout_timeout_callback).
-
-    The following options are important for tuning Mongoose only if you are
-    running **with** [the `useUnifiedTopology` option](/docs/deprecations.html#useunifiedtopology):
-
-    * `serverSelectionTimeoutMS` - With `useUnifiedTopology`, the MongoDB driver will try to find a server to send any given operation to, and keep retrying for `serverSelectionTimeoutMS` milliseconds. If not set, the MongoDB driver defaults to using `30000` (30 seconds).
-    * `heartbeatFrequencyMS` - With `useUnifiedTopology`, the MongoDB driver sends a heartbeat every `heartbeatFrequencyMS` to check on the status of the connection. A heartbeat is subject to `serverSelectionTimeoutMS`, so the MongoDB driver will retry failed heartbeats for up to 30 seconds by default. Mongoose only emits a `'disconnected'` event after a heartbeat has failed, so you may want to decrease this setting to reduce the time between when your server goes down and when Mongoose emits `'disconnected'`. We recommend you do **not** set this setting below 1000, too many heartbeats can lead to performance degradation.
-
-    The `serverSelectionTimeoutMS` option also handles how long `mongoose.connect()` will
-    retry initial connection before erroring out. With `useUnifiedTopology`, `mongoose.connect()`
-    will retry for 30 seconds by default (default `serverSelectionTimeoutMS`) before
-    erroring out. To get faster feedback on failed operations, you can reduce `serverSelectionTimeoutMS`
-    to 5000 as shown below.
-
-    Example:
-
-    ```javascript
-    const options = {
-      useNewUrlParser: true,
-      useUnifiedTopology: true,
-      useCreateIndex: true,
-      useFindAndModify: false,
-      autoIndex: false, // Don't build indexes
-      poolSize: 10, // Maintain up to 10 socket connections
-      serverSelectionTimeoutMS: 5000, // Keep trying to send operations for 5 seconds
-      socketTimeoutMS: 45000, // Close sockets after 45 seconds of inactivity
-      family: 4 // Use IPv4, skip trying IPv6
-    };
-    mongoose.connect(uri, options);
-    ```
-
-    See [this page](http://mongodb.github.io/node-mongodb-native/3.1/reference/faq/) for more information about `connectTimeoutMS` and `socketTimeoutMS`
-
-    <h3 id="callback"><a href="#callback">Callback</a></h3>
-
-    The `connect()` function also accepts a callback parameter and returns a
-    [promise](./promises.html).
-
-    ```javascript
-    mongoose.connect(uri, options, function(error) {
-      // Check error in initial connection. There is no 2nd param to the callback.
-    });
-
-    // Or using promises
-    mongoose.connect(uri, options).then(
-      () => { /** ready to use. The `mongoose.connect()` promise resolves to mongoose instance. */ },
-      err => { /** handle initial connection error */ }
-    );
-    ```
-
-    <h3 id="connection-string-options"><a href="#connection-string-options">Connection String Options</a></h3>
-
-    You can also specify driver options in your connection string as
-    [parameters in the query string](https://en.wikipedia.org/wiki/Query_string)
-    portion of the URI. This only applies to options passed to the MongoDB
-    driver. You **can't** set Mongoose-specific options like `bufferCommands`
-    in the query string.
-
-    ```javascript
-    mongoose.connect('mongodb://localhost:27017/test?connectTimeoutMS=1000&bufferCommands=false&authSource=otherdb');
-    // The above is equivalent to:
-    mongoose.connect('mongodb://localhost:27017/test', {
-      connectTimeoutMS: 1000
-      // Note that mongoose will **not** pull `bufferCommands` from the query string
-    });
-    ```
-
-    The disadvantage of putting options in the query string is that query
-    string options are harder to read. The advantage is that you only need a
-    single configuration option, the URI, rather than separate options for
-    `socketTimeoutMS`, `connectTimeoutMS`, etc. Best practice is to put options
-    that likely differ between development and production, like `replicaSet`
-    or `ssl`, in the connection string, and options that should remain constant,
-    like `connectTimeoutMS` or `poolSize`, in the options object.
-
-    The MongoDB docs have a full list of
-    [supported connection string options](https://docs.mongodb.com/manual/reference/connection-string/).
-    Below are some options that are often useful to set in the connection string because they
-    are closely associated with the hostname and authentication information.
-
-    * `authSource`        - The database to use when authenticating with `user` and `pass`. In MongoDB, [users are scoped to a database](https://docs.mongodb.com/manual/tutorial/manage-users-and-roles/). If you are getting an unexpected login failure, you may need to set this option.
-    * `family`            - Whether to connect using IPv4 or IPv6. This option passed to [Node.js' `dns.lookup()`](https://nodejs.org/api/dns.html#dns_dns_lookup_hostname_options_callback) function. If you don't specify this option, the MongoDB driver will try IPv6 first and then IPv4 if IPv6 fails. If your `mongoose.connect(uri)` call takes a long time, try `mongoose.connect(uri, { family: 4 })`
-
-    <h3 id="connection-events"><a href="#connection-events">Connection Events</a></h3>
-
-    Connections inherit from [Node.js' `EventEmitter` class](https://nodejs.org/api/events.html#events_class_eventemitter),
-    and emit events when something happens to the connection, like losing
-    connectivity to the MongoDB server. Below is a list of events that a
-    connection may emit.
-
-    * `connecting`: Emitted when Mongoose starts making its initial connection to the MongoDB server
-    * `connected`: Emitted when Mongoose successfully makes its initial connection to the MongoDB server, or when Mongoose reconnects after losing connectivity.
-    * `open`: Equivalent to `connected`
-    * `disconnecting`: Your app called [`Connection#close()`](api.html#connection_Connection-close) to disconnect from MongoDB
-    * `disconnected`: Emitted when Mongoose lost connection to the MongoDB server. This event may be due to your code explicitly closing the connection, the database server crashing, or network connectivity issues.
-    * `close`: Emitted after [`Connection#close()`](api.html#connection_Connection-close) successfully closes the connection. If you call `conn.close()`, you'll get both a 'disconnected' event and a 'close' event.
-    * `reconnected`: Emitted if Mongoose lost connectivity to MongoDB and successfully reconnected. Mongoose attempts to [automatically reconnect](https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html) when it loses connection to the database.
-    * `error`: Emitted if an error occurs on a connection, like a `parseError` due to malformed data or a payload larger than [16MB](https://docs.mongodb.com/manual/reference/limits/#BSON-Document-Size).
-    * `fullsetup`: Emitted when you're connecting to a replica set and Mongoose has successfully connected to the primary and at least one secondary.
-    * `all`: Emitted when you're connecting to a replica set and Mongoose has successfully connected to all servers specified in your connection string.
-    * `reconnectFailed`: Emitted when you're connected to a standalone server and Mongoose has run out of [`reconnectTries`](https://thecodebarbarian.com/managing-connections-with-the-mongodb-node-driver.html#handling-single-server-outages). The [MongoDB driver](http://npmjs.com/package/mongodb) will no longer attempt to reconnect after this event is emitted. This event will never be emitted if you're connected to a replica set.
-
-    When you're connecting to a single MongoDB server (a "standalone"), Mongoose will emit 'disconnected' if it gets
-    disconnected from the standalone server, and 'connected' if it successfully connects to the standalone. In a
-    replica set with `useUnifiedTopology = true`, Mongoose will emit 'disconnected' if it loses connectivity to
-    _every_ server in the replica set, and 'connected' if it manages to reconnect to at least one server in the replica set.
-
-    <h3 id="keepAlive"><a href="#keepAlive">A note about keepAlive</a></h3>
-
-    For long running applications, it is often prudent to enable `keepAlive`
-    with a number of milliseconds. Without it, after some period of time
-    you may start to see `"connection closed"` errors for what seems like
-    no reason. If so, after
-    [reading this](http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/overview.html),
-    you may decide to enable `keepAlive`:
-
-    ```javascript
-    mongoose.connect(uri, { keepAlive: true, keepAliveInitialDelay: 300000 });
-    ```
-
-    `keepAliveInitialDelay` is the number of milliseconds to wait before initiating `keepAlive` on the socket.
-    `keepAlive` is true by default since mongoose 5.2.0.
-
-    <h3 id="replicaset_connections"><a href="#replicaset_connections">Replica Set Connections</a></h3>
-
-    To connect to a replica set you pass a comma delimited list of hosts to
-    connect to rather than a single host.
-
-    ```javascript
-    mongoose.connect('mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]' [, options]);
-    ```
-
-    For example:
-
-    ```javascript
-    mongoose.connect('mongodb://user:pw@host1.com:27017,host2.com:27017,host3.com:27017/testdb');
-    ```
-
-    To connect to a single node replica set, specify the `replicaSet` option.
-
-    ```javascript
-    mongoose.connect('mongodb://host1:port1/?replicaSet=rsName');
-    ```
-
-    <h3 id="server-selection"><a href="#server-selection">Server Selection</a></h3>
-
-    If you enable the `useUnifiedTopology` option, the underlying MongoDB driver
-    will use [server selection](https://github.com/mongodb/specifications/blob/master/source/server-selection/server-selection.rst)
-    to connect to MongoDB and send operations to MongoDB. If the MongoDB
-    driver can't find a server to send an operation to after `serverSelectionTimeoutMS`,
-    you'll get the below error:
-    
-    ```
-    MongoTimeoutError: Server selection timed out after 30000 ms
-    ```
-
-    You can configure the timeout using the `serverSelectionTimeoutMS` option
-    to `mongoose.connect()`:
-
-    ```javascript
-    mongoose.connect(uri, {
-      useNewUrlParser: true,
-      useUnifiedTopology: true,
-      serverSelectionTimeoutMS: 5000 // Timeout after 5s instead of 30s
-    });
-    ```
-
-    A `MongoTimeoutError` has a `reason` property that explains why
-    server selection timed out. For example, if you're connecting to
-    a standalone server with an incorrect password, `reason`
-    will contain an "Authentication failed" error.
-
-    ```javascript
-    const mongoose = require('mongoose');
-
-    const uri = 'mongodb+srv://username:badpw@cluster0-OMITTED.mongodb.net/' +
-      'test?retryWrites=true&w=majority';
-    // Prints "MongoError: bad auth Authentication failed."
-    mongoose.connect(uri, {
-      useNewUrlParser: true,
-      useUnifiedTopology: true,
-      serverSelectionTimeoutMS: 5000
-    }).catch(err => console.log(err.reason));
-    ```
-
-    <h3 id="replicaset-hostnames"><a href="#replicaset-hostnames">Replica Set Host Names</a></h3>
-
-    MongoDB replica sets rely on being able to reliably figure out the domain name
-    for each member. On Linux and OSX, the MongoDB server uses the output of the
-    [`hostname` command](https://linux.die.net/man/1/hostname) to figure out the
-    domain name to report to the replica set. This can cause confusing errors
-    if you're connecting to a remote MongoDB replica set running on a machine that
-    reports its `hostname` as `localhost`:
-
-    ```
-    // Can get this error even if your connection string doesn't include
-    // `localhost` if `rs.conf()` reports that one replica set member has
-    // `localhost` as its host name.
-    failed to connect to server [localhost:27017] on first connect
-    ```
-
-    If you're experiencing a similar error, connect to the replica set using the
-    `mongo` shell and run the
-    [`rs.conf()`](https://docs.mongodb.com/manual/reference/method/rs.conf/) command to check the host names of each replica set member. Follow
-    [this page's instructions to change a replica set member's host name](https://docs.mongodb.com/manual/tutorial/change-hostnames-in-a-replica-set/#change-hostnames-while-maintaining-replica-set-availability).
-
-    <h3 id="mongos_connections"><a href="#mongos_connections">Multi-mongos support</a></h3>
-
-    You can also connect to multiple [mongos](https://docs.mongodb.com/manual/reference/program/mongos/) instances
-    for high availability in a sharded cluster. You do
-    [not need to pass any special options to connect to multiple mongos](http://mongodb.github.io/node-mongodb-native/3.0/tutorials/connect/#connect-to-sharded-cluster) in mongoose 5.x.
-
-    ```javascript
-    // Connect to 2 mongos servers
-    mongoose.connect('mongodb://mongosA:27501,mongosB:27501', cb);
-    ```
-
-    <h3 id="multiple_connections"><a href="#multiple_connections">Multiple connections</a></h3>
-
-    So far we've seen how to connect to MongoDB using Mongoose's default
-    connection. Mongoose creates a _default connection_ when you call `mongoose.connect()`.
-    You can access the default connection using `mongoose.connection`.
-    
-    You may need multiple connections to MongoDB for several reasons.
-    One reason is if you have multiple databases or multiple MongoDB clusters.
-    Another reason is to work around [slow trains](https://thecodebarbarian.com/slow-trains-in-mongodb-and-nodejs).
-    The `mongoose.createConnection()` function takes the same arguments as
-    `mongoose.connect()` and returns a new connection.
-
-    ```javascript
-    const conn = mongoose.createConnection('mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]', options);
-    ```
-
-    This [connection](./api.html#connection_Connection) object is then used to
-    create and retrieve [models](./api.html#model_Model). Models are
-    **always** scoped to a single connection.
-
-    ```javascript
-    const UserModel = conn.model('User', userSchema);
-    ```
-
-    If you use multiple connections, you should make sure you export schemas,
-    **not** models. Exporting a model from a file is called the _export model pattern_.
-    The export model pattern is limited because you can only use one connection.
-
-    ```javascript
-    const userSchema = new Schema({ name: String, email: String });
-
-    // The alternative to the export model pattern is the export schema pattern.
-    module.exports = userSchema;
-
-    // Because if you export a model as shown below, the model will be scoped
-    // to Mongoose's default connection.
-    // module.exports = mongoose.model('User', userSchema);
-    ```
-
-    If you use the export schema pattern, you still need to create models
-    somewhere. There are two common patterns. First is to export a connection
-    and register the models on the connection in the file:
-
-    ```javascript
-    // connections/fast.js
-    const mongoose = require('mongoose');
-
-    const conn = mongoose.createConnection(process.env.MONGODB_URI);
-    conn.model('User', require('../schemas/user'));
-
-    module.exports = conn;
-
-    // connections/slow.js
-    const mongoose = require('mongoose');
-
-    const conn = mongoose.createConnection(process.env.MONGODB_URI);
-    conn.model('User', require('../schemas/user'));
-    conn.model('PageView', require('../schemas/pageView'));
-
-    module.exports = conn;
-    ```
-
-    Another alternative is to register connections with a dependency injector
-    or another [inversion of control (IOC) pattern](https://thecodebarbarian.com/using-ramda-as-a-dependency-injector).
-
-    ```javascript
-    const mongoose = require('mongoose');
-
-    module.exports = function connectionFactory() {
-      const conn = mongoose.createConnection(process.env.MONGODB_URI);
-
-      conn.model('User', require('../schemas/user'));
-      conn.model('PageView', require('../schemas/pageView'));
-
-      return conn; 
-    };
-    ```
-
-    <h3 id="connection_pools"><a href="#connection_pools">Connection Pools</a></h3>
-
-    Each `connection`, whether created with `mongoose.connect` or
-    `mongoose.createConnection` are all backed by an internal configurable
-    connection pool defaulting to a maximum size of 5. Adjust the pool size
-    using your connection options:
-
-    ```javascript
-    // With object options
-    mongoose.createConnection(uri, { poolSize: 4 });
-
-    const uri = 'mongodb://localhost:27017/test?poolSize=4';
-    mongoose.createConnection(uri);
-    ```
-
-    <h3 id="v5-changes"><a href="#v5-changes">Option Changes in v5.x</a></h3>
-
-    You may see the following deprecation warning if upgrading from 4.x to 5.x
-    and you didn't use the `useMongoClient` option in 4.x:
-
-    ```
-    the server/replset/mongos options are deprecated, all their options are supported at the top level of the options object
-    ```
-
-    In older version of the MongoDB driver you had to specify distinct options
-    for server connections, replica set connections, and mongos connections:
-
-    ```javascript
-    mongoose.connect(myUri, {
-      server: {
-        socketOptions: {
-          socketTimeoutMS: 0,
-          keepAlive: true
-        },
-        reconnectTries: 30
-      },
-      replset: {
-        socketOptions: {
-          socketTimeoutMS: 0,
-          keepAlive: true
-        },
-        reconnectTries: 30
-      },
-      mongos: {
-        socketOptions: {
-          socketTimeoutMS: 0,
-          keepAlive: true
-        },
-        reconnectTries: 30
-      }
-    });
-    ```
-
-    In mongoose v5.x you can instead declare these options at the top level,
-    without all that extra nesting.
-    [Here's the list of all supported options](http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html).
-
-    ```javascript
-    // Equivalent to the above code
-    mongoose.connect(myUri, {
-      socketTimeoutMS: 0,
-      keepAlive: true,
-      reconnectTries: 30
-    });
-    ```
-
-    <h3 id="next">Next Up</h3>
-
-    Now that we've covered connections, let's take a look at [models](/docs/models.html).
diff --git a/docs/contributing.md b/docs/contributing.md
new file mode 100644
index 00000000000..24d8f1d78a1
--- /dev/null
+++ b/docs/contributing.md
@@ -0,0 +1,3 @@
+## Contributing
+
+Please read all about contributing [here](https://github.com/Automattic/mongoose/blob/master/CONTRIBUTING.md).
\ No newline at end of file
diff --git a/docs/contributing.pug b/docs/contributing.pug
deleted file mode 100644
index 1e5e96af214..00000000000
--- a/docs/contributing.pug
+++ /dev/null
@@ -1,7 +0,0 @@
-extends layout
-
-block content
-  :markdown
-    ## Contributing
-
-    Please read all about contributing [here](https://github.com/Automattic/mongoose/blob/master/CONTRIBUTING.md).
diff --git a/docs/deprecations.md b/docs/deprecations.md
new file mode 100644
index 00000000000..f8a3472bc54
--- /dev/null
+++ b/docs/deprecations.md
@@ -0,0 +1,293 @@
+# Deprecation Warnings
+
+There are several deprecations in the [MongoDB Node.js driver](http://npmjs.com/package/mongodb)
+that Mongoose users should be aware of. Mongoose provides options to work
+around these deprecation warnings, but you need to test whether these options
+cause any problems for your application. Please [report any issues on GitHub](https://github.com/Automattic/mongoose/issues/new).
+
+<h2 id="summary"><a href="#summary">Summary</a></h2>
+
+To fix all deprecation warnings, follow the below steps:
+
+* `mongoose.set('useNewUrlParser', true);`
+* `mongoose.set('useFindAndModify', false);`
+* `mongoose.set('useCreateIndex', true);`
+* `mongoose.set('useUnifiedTopology', true);`
+* Replace `update()` with `updateOne()`, `updateMany()`, or `replaceOne()`
+* Replace `remove()` with `deleteOne()` or `deleteMany()`.
+* Replace `count()` with `countDocuments()`, unless you want to count how many documents are in the whole collection (no filter). In the latter case, use `estimatedDocumentCount()`.
+
+Read below for more a more detailed description of each deprecation warning.
+
+<h2 id="the-usenewurlparser-option"><a href="#the-usenewurlparser-option">The <code>useNewUrlParser</code> Option</a></h2>
+
+By default, `mongoose.connect()` will print out the below warning:
+
+```
+DeprecationWarning: current URL string parser is deprecated, and will be
+removed in a future version. To use the new parser, pass option
+{ useNewUrlParser: true } to MongoClient.connect.
+```
+
+The MongoDB Node.js driver rewrote the tool it uses to parse [MongoDB connection strings](https://docs.mongodb.com/manual/reference/connection-string/).
+Because this is such a big change, they put the new connection string parser
+behind a flag. To turn on this option, pass the `useNewUrlParser` option to
+[`mongoose.connect()`](/docs/api.html#mongoose_Mongoose-connect)
+or [`mongoose.createConnection()`](/docs/api.html#mongoose_Mongoose-createConnection).
+
+```javascript
+mongoose.connect(uri, { useNewUrlParser: true });
+mongoose.createConnection(uri, { useNewUrlParser: true });
+```
+
+You can also [set the global `useNewUrlParser` option](/docs/api.html#mongoose_Mongoose-set)
+to turn on `useNewUrlParser` for every connection by default.
+
+```javascript
+// Optional. Use this if you create a lot of connections and don't want
+// to copy/paste `{ useNewUrlParser: true }`.
+mongoose.set('useNewUrlParser', true);
+```
+
+To test your app with `{ useNewUrlParser: true }`, you only need to check
+whether your app successfully connects. Once Mongoose has successfully
+connected, the URL parser is no longer important. If you can't connect
+with `{ useNewUrlParser: true }`, please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
+
+<h2 id="findandmodify"><a href="#findandmodify"><code>findAndModify()</code></a></h2>
+
+If you use [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate),
+by default you'll see one of the below deprecation warnings.
+
+```
+DeprecationWarning: Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the `useFindAndModify` option set to false are deprecated. See: https://mongoosejs.com/docs/deprecations.html#findandmodify
+DeprecationWarning: collection.findAndModify is deprecated. Use findOneAndUpdate, findOneAndReplace or findOneAndDelete instead.
+```
+
+Mongoose's `findOneAndUpdate()` long pre-dates the MongoDB driver's `findOneAndUpdate()`
+function, so it uses the MongoDB driver's [`findAndModify()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#findAndModify)
+instead. You can opt in to using the MongoDB driver's `findOneAndUpdate()`
+function using the [`useFindAndModify` global option](/docs/api.html#mongoose_Mongoose-set).
+
+```javascript
+// Make Mongoose use `findOneAndUpdate()`. Note that this option is `true`
+// by default, you need to set it to false.
+mongoose.set('useFindAndModify', false);
+```
+
+You can also configure `useFindAndModify` by passing it through the connection options.
+
+```javascript
+mongoose.connect(uri, { useFindAndModify: false });
+```
+
+This option affects the following model and query functions. There are
+no intentional backwards breaking changes, so you should be able to turn
+this option on without any code changes. If you discover any issues,
+please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
+
+* [`Model.findByIdAndDelete()`](/docs/api.html#model_Model.findByIdAndDelete)
+* [`Model.findByIdAndRemove()`](/docs/api.html#model_Model.findByIdAndRemove)
+* [`Model.findByIdAndUpdate()`](/docs/api.html#model_Model.findByIdAndUpdate)
+* [`Model.findOneAndDelete()`](/docs/api.html#model_Model.findOneAndDelete)
+* [`Model.findOneAndRemove()`](/docs/api.html#model_Model.findOneAndRemove)
+* [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate)
+* [`Query.findOneAndDelete()`](/docs/api.html#query_Query-findOneAndDelete)
+* [`Query.findOneAndRemove()`](/docs/api.html#query_Query-findOneAndRemove)
+* [`Query.findOneAndUpdate()`](/docs/api.html#query_Query-findOneAndUpdate)
+
+You can also safely ignore this warning. Mongoose will not remove the legacy `useFindAndModify: true`
+behavior until Mongoose 6.0.
+
+<h2 id="ensureindex"><a href="#ensureindex"><code>ensureIndex()</code></a></h2>
+
+If you define [indexes in your Mongoose schemas](https://mongoosejs.com/docs/guide.html#indexes), you'll see the below
+deprecation warning.
+
+```
+DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes
+instead.
+```
+
+By default, Mongoose 5.x calls the [MongoDB driver's `ensureIndex()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#ensureIndex).
+The MongoDB driver deprecated this function in favor of [`createIndex()`](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#createIndex).
+Set the [`useCreateIndex` global option](/docs/api.html#mongoose_Mongoose-set) to opt in to making Mongoose use `createIndex()` instead.
+
+```javascript
+mongoose.set('useCreateIndex', true);
+```
+
+You can also configure `useCreateIndex` by passing it through the connection options.
+
+```javascript
+mongoose.connect(uri, { useCreateIndex: true });
+```
+
+There are no intentional backwards breaking changes with the `useCreateIndex`
+option, so you should be able to turn
+this option on without any code changes. If you discover any issues,
+please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
+
+You can also safely ignore this warning. Mongoose will not remove the legacy `useCreateIndex: false`
+behavior until Mongoose 6.0.
+
+<h2 id="remove"><a href="#remove"><code>remove()</code></a></h2>
+
+The MongoDB driver's [`remove()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove) is deprecated in favor of `deleteOne()` and `deleteMany()`. This is to comply with
+the [MongoDB CRUD specification](https://github.com/mongodb/specifications/blob/master/source/crud/crud.rst),
+which aims to provide a consistent API for CRUD operations across all MongoDB
+drivers.
+
+```
+DeprecationWarning: collection.remove is deprecated. Use deleteOne,
+deleteMany, or bulkWrite instead.
+```
+
+To remove this deprecation warning, replace any usage of `remove()` with
+`deleteMany()`, _unless_ you specify the [`single` option to `remove()`](/docs/api.html#model_Model.remove). The `single`
+option limited `remove()` to deleting at most one document, so you should
+replace `remove(filter, { single: true })` with `deleteOne(filter)`.
+
+```javascript
+// Replace this:
+MyModel.remove({ foo: 'bar' });
+// With this:
+MyModel.deleteMany({ foo: 'bar' });
+
+// Replace this:
+MyModel.remove({ answer: 42 }, { single: true });
+// With this:
+MyModel.deleteOne({ answer: 42 });
+```
+
+<h2 id="useunifiedtopology"><a href="#useunifiedtopology"><code>useUnifiedTopology</code></a></h2>
+
+By default, `mongoose.connect()` will print out the below warning:
+
+```
+DeprecationWarning: current Server Discovery and Monitoring engine is
+deprecated, and will be removed in a future version. To use the new Server
+Discover and Monitoring engine, pass option { useUnifiedTopology: true } to
+the MongoClient constructor.
+```
+
+Mongoose 5.7 uses MongoDB driver 3.3.x, which introduced a significant
+refactor of how it handles monitoring all the servers in a replica set
+or sharded cluster. In MongoDB parlance, this is known as
+[server discovery and monitoring](https://github.com/mongodb/specifications/blob/master/source/server-discovery-and-monitoring/server-discovery-and-monitoring.rst).
+
+To opt in to using the new topology engine, use the below line:
+
+```javascript
+mongoose.set('useUnifiedTopology', true);
+```
+
+The `useUnifiedTopology` option removes support for several
+[connection options](/docs/connections.html#options) that are
+no longer relevant with the new topology engine:
+
+- `autoReconnect`
+- `reconnectTries`
+- `reconnectInterval`
+
+When you enable `useUnifiedTopology`, please remove those options
+from your [`mongoose.connect()`](/docs/api/mongoose.html#mongoose_Mongoose-connect) or
+[`createConnection()`](/docs/api/mongoose.html#mongoose_Mongoose-createConnection) calls.
+
+If you find any unexpected behavior, please [open up an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
+
+<h2 id="update"><a href="#update"><code>update()</code></a></h2>
+
+Like `remove()`, the [`update()` function](/docs/api.html#model_Model.update) is deprecated in favor
+of the more explicit [`updateOne()`](/docs/api.html#model_Model.updateOne), [`updateMany()`](/docs/api.html#model_Model.updateMany), and [`replaceOne()`](/docs/api.html#model_Model.replaceOne) functions. You should replace
+`update()` with `updateOne()`, unless you use the [`multi` or `overwrite` options](/docs/api.html#model_Model.update).
+
+```
+collection.update is deprecated. Use updateOne, updateMany, or bulkWrite
+instead.
+```
+
+```javascript
+// Replace this:
+MyModel.update({ foo: 'bar' }, { answer: 42 });
+// With this:
+MyModel.updateOne({ foo: 'bar' }, { answer: 42 });
+
+// If you use `overwrite: true`, you should use `replaceOne()` instead:
+MyModel.update(filter, update, { overwrite: true });
+// Replace with this:
+MyModel.replaceOne(filter, update);
+
+// If you use `multi: true`, you should use `updateMany()` instead:
+MyModel.update(filter, update, { multi: true });
+// Replace with this:
+MyModel.updateMany(filter, update);
+```
+
+<h2 id="count"><a href="#count"><code>count()</code></a></h2>
+
+The MongoDB server has deprecated the `count()` function in favor of two
+separate functions, [`countDocuments()`](#query_Query-countDocuments) and
+[`estimatedDocumentCount()`](#query_Query-estimatedDocumentCount).
+
+```
+DeprecationWarning: collection.count is deprecated, and will be removed in a future version. Use collection.countDocuments or collection.estimatedDocumentCount instead
+```
+
+The difference between the two is `countDocuments()` can accept a filter
+parameter like [`find()`](#query_Query-find). The `estimatedDocumentCount()`
+function is faster, but can only tell you the total number of documents in
+a collection. You cannot pass a `filter` to `estimatedDocumentCount()`.
+
+To migrate, replace `count()` with `countDocuments()` _unless_ you do not
+pass any arguments to `count()`. If you use `count()` to count all documents
+in a collection as opposed to counting documents that match a query, use
+`estimatedDocumentCount()` instead of `countDocuments()`.
+
+```javascript
+// Replace this:
+MyModel.count({ answer: 42 });
+// With this:
+MyModel.countDocuments({ answer: 42 });
+
+// If you're counting all documents in the collection, use
+// `estimatedDocumentCount()` instead.
+MyModel.count();
+// Replace with:
+MyModel.estimatedDocumentCount();
+
+// Replace this:
+MyModel.find({ answer: 42 }).count().exec();
+// With this:
+MyModel.find({ answer: 42 }).countDocuments().exec();
+
+// Replace this:
+MyModel.find().count().exec();
+// With this, since there's no filter
+MyModel.find().estimatedDocumentCount().exec();
+```
+
+<h2 id="gridstore"><a href="#gridstore"><code>GridStore</code></a></h2>
+
+If you're using [gridfs-stream](https://www.npmjs.com/package/gridfs-stream),
+you'll see the below deprecation warning:
+
+```
+DeprecationWarning: GridStore is deprecated, and will be removed in a
+future version. Please use GridFSBucket instead.
+```
+
+That is because gridfs-stream relies on a [deprecated MongoDB driver class](http://mongodb.github.io/node-mongodb-native/3.1/api/GridStore.html).
+You should instead use the [MongoDB driver's own streaming API](https://thecodebarbarian.com/mongodb-gridfs-stream).
+
+```javascript
+// Replace this:
+const conn = mongoose.createConnection('mongodb://localhost:27017/gfstest');
+const gfs = require('gridfs-store')(conn.db);
+const writeStream = gfs.createWriteStream({ filename: 'test.dat' });
+
+// With this:
+const conn = mongoose.createConnection('mongodb://localhost:27017/gfstest');
+const gridFSBucket = new mongoose.mongo.GridFSBucket(conn.db);
+const writeStream = gridFSBucket.openUploadStream('test.dat');
+```
\ No newline at end of file
diff --git a/docs/deprecations.pug b/docs/deprecations.pug
deleted file mode 100644
index 784219ec113..00000000000
--- a/docs/deprecations.pug
+++ /dev/null
@@ -1,313 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Deprecation Warnings
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    There are several deprecations in the [MongoDB Node.js driver](http://npmjs.com/package/mongodb)
-    that Mongoose users should be aware of. Mongoose provides options to work
-    around these deprecation warnings, but you need to test whether these options
-    cause any problems for your application. Please [report any issues on GitHub](https://github.com/Automattic/mongoose/issues/new).
-
-    <h2 id="summary"><a href="#summary">Summary</a></h2>
-
-    To fix all deprecation warnings, follow the below steps:
-
-    * `mongoose.set('useNewUrlParser', true);`
-    * `mongoose.set('useFindAndModify', false);`
-    * `mongoose.set('useCreateIndex', true);`
-    * `mongoose.set('useUnifiedTopology', true);`
-    * Replace `update()` with `updateOne()`, `updateMany()`, or `replaceOne()`
-    * Replace `remove()` with `deleteOne()` or `deleteMany()`.
-    * Replace `count()` with `countDocuments()`, unless you want to count how many documents are in the whole collection (no filter). In the latter case, use `estimatedDocumentCount()`.
-
-    Read below for more a more detailed description of each deprecation warning.
-
-    <h2 id="the-usenewurlparser-option"><a href="#the-usenewurlparser-option">The <code>useNewUrlParser</code> Option</a></h2>
-
-    By default, `mongoose.connect()` will print out the below warning:
-
-    ```
-    DeprecationWarning: current URL string parser is deprecated, and will be
-    removed in a future version. To use the new parser, pass option
-    { useNewUrlParser: true } to MongoClient.connect.
-    ```
-
-    The MongoDB Node.js driver rewrote the tool it uses to parse [MongoDB connection strings](https://docs.mongodb.com/manual/reference/connection-string/).
-    Because this is such a big change, they put the new connection string parser
-    behind a flag. To turn on this option, pass the `useNewUrlParser` option to
-    [`mongoose.connect()`](/docs/api.html#mongoose_Mongoose-connect)
-    or [`mongoose.createConnection()`](/docs/api.html#mongoose_Mongoose-createConnection).
-
-    ```javascript
-    mongoose.connect(uri, { useNewUrlParser: true });
-    mongoose.createConnection(uri, { useNewUrlParser: true });
-    ```
-
-    You can also [set the global `useNewUrlParser` option](/docs/api.html#mongoose_Mongoose-set)
-    to turn on `useNewUrlParser` for every connection by default.
-
-    ```javascript
-    // Optional. Use this if you create a lot of connections and don't want
-    // to copy/paste `{ useNewUrlParser: true }`.
-    mongoose.set('useNewUrlParser', true);
-    ```
-
-    To test your app with `{ useNewUrlParser: true }`, you only need to check
-    whether your app successfully connects. Once Mongoose has successfully
-    connected, the URL parser is no longer important. If you can't connect
-    with `{ useNewUrlParser: true }`, please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
-
-    <h2 id="findandmodify"><a href="#findandmodify"><code>findAndModify()</code></a></h2>
-
-    If you use [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate),
-    by default you'll see one of the below deprecation warnings.
-
-    ```
-    DeprecationWarning: Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the `useFindAndModify` option set to false are deprecated. See: https://mongoosejs.com/docs/deprecations.html#findandmodify
-    DeprecationWarning: collection.findAndModify is deprecated. Use findOneAndUpdate, findOneAndReplace or findOneAndDelete instead.
-    ```
-
-    Mongoose's `findOneAndUpdate()` long pre-dates the MongoDB driver's `findOneAndUpdate()`
-    function, so it uses the MongoDB driver's [`findAndModify()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#findAndModify)
-    instead. You can opt in to using the MongoDB driver's `findOneAndUpdate()`
-    function using the [`useFindAndModify` global option](/docs/api.html#mongoose_Mongoose-set).
-
-    ```javascript
-    // Make Mongoose use `findOneAndUpdate()`. Note that this option is `true`
-    // by default, you need to set it to false.
-    mongoose.set('useFindAndModify', false);
-    ```
-
-    You can also configure `useFindAndModify` by passing it through the connection options.
-    ```javascript
-    mongoose.connect(uri, { useFindAndModify: false });
-    ```
-
-    This option affects the following model and query functions. There are
-    no intentional backwards breaking changes, so you should be able to turn
-    this option on without any code changes. If you discover any issues,
-    please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
-
-    * [`Model.findByIdAndDelete()`](/docs/api.html#model_Model.findByIdAndDelete)
-    * [`Model.findByIdAndRemove()`](/docs/api.html#model_Model.findByIdAndRemove)
-    * [`Model.findByIdAndUpdate()`](/docs/api.html#model_Model.findByIdAndUpdate)
-    * [`Model.findOneAndDelete()`](/docs/api.html#model_Model.findOneAndDelete)
-    * [`Model.findOneAndRemove()`](/docs/api.html#model_Model.findOneAndRemove)
-    * [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate)
-    * [`Query.findOneAndDelete()`](/docs/api.html#query_Query-findOneAndDelete)
-    * [`Query.findOneAndRemove()`](/docs/api.html#query_Query-findOneAndRemove)
-    * [`Query.findOneAndUpdate()`](/docs/api.html#query_Query-findOneAndUpdate)
-
-    You can also safely ignore this warning. Mongoose will not remove the legacy `useFindAndModify: true`
-    behavior until Mongoose 6.0.
-
-    <h2 id="ensureindex"><a href="#ensureindex"><code>ensureIndex()</code></a></h2>
-
-    If you define [indexes in your Mongoose schemas](https://mongoosejs.com/docs/guide.html#indexes), you'll see the below
-    deprecation warning.
-
-    ```
-    DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes
-    instead.
-    ```
-
-    By default, Mongoose 5.x calls the [MongoDB driver's `ensureIndex()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#ensureIndex).
-    The MongoDB driver deprecated this function in favor of [`createIndex()`](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#createIndex).
-    Set the [`useCreateIndex` global option](/docs/api.html#mongoose_Mongoose-set) to opt in to making Mongoose use `createIndex()` instead.
-
-    ```javascript
-    mongoose.set('useCreateIndex', true);
-    ```
-
-    You can also configure `useCreateIndex` by passing it through the connection options.
-    ```javascript
-    mongoose.connect(uri, { useCreateIndex: true });
-    ```
-
-    There are no intentional backwards breaking changes with the `useCreateIndex`
-    option, so you should be able to turn
-    this option on without any code changes. If you discover any issues,
-    please [open an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
-
-    You can also safely ignore this warning. Mongoose will not remove the legacy `useCreateIndex: false`
-    behavior until Mongoose 6.0.
-
-    <h2 id="remove"><a href="#remove"><code>remove()</code></a></h2>
-
-    The MongoDB driver's [`remove()` function](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#remove) is deprecated in favor of `deleteOne()` and `deleteMany()`. This is to comply with
-    the [MongoDB CRUD specification](https://github.com/mongodb/specifications/blob/master/source/crud/crud.rst),
-    which aims to provide a consistent API for CRUD operations across all MongoDB
-    drivers.
-
-    ```
-    DeprecationWarning: collection.remove is deprecated. Use deleteOne,
-    deleteMany, or bulkWrite instead.
-    ```
-
-    To remove this deprecation warning, replace any usage of `remove()` with
-    `deleteMany()`, _unless_ you specify the [`single` option to `remove()`](/docs/api.html#model_Model.remove). The `single`
-    option limited `remove()` to deleting at most one document, so you should
-    replace `remove(filter, { single: true })` with `deleteOne(filter)`.
-
-    ```javascript
-    // Replace this:
-    MyModel.remove({ foo: 'bar' });
-    // With this:
-    MyModel.deleteMany({ foo: 'bar' });
-
-    // Replace this:
-    MyModel.remove({ answer: 42 }, { single: true });
-    // With this:
-    MyModel.deleteOne({ answer: 42 });
-    ```
-
-    <h2 id="useunifiedtopology"><a href="#useunifiedtopology"><code>useUnifiedTopology</code></a></h2>
-
-    By default, `mongoose.connect()` will print out the below warning:
-
-    ```
-    DeprecationWarning: current Server Discovery and Monitoring engine is
-    deprecated, and will be removed in a future version. To use the new Server
-    Discover and Monitoring engine, pass option { useUnifiedTopology: true } to
-    the MongoClient constructor.
-    ```
-
-    Mongoose 5.7 uses MongoDB driver 3.3.x, which introduced a significant
-    refactor of how it handles monitoring all the servers in a replica set
-    or sharded cluster. In MongoDB parlance, this is known as
-    [server discovery and monitoring](https://github.com/mongodb/specifications/blob/master/source/server-discovery-and-monitoring/server-discovery-and-monitoring.rst).
-
-    To opt in to using the new topology engine, use the below line:
-
-    ```javascript
-    mongoose.set('useUnifiedTopology', true);
-    ```
-
-    The `useUnifiedTopology` option removes support for several
-    [connection options](/docs/connections.html#options) that are
-    no longer relevant with the new topology engine:
-
-    - `autoReconnect`
-    - `reconnectTries`
-    - `reconnectInterval`
-
-    When you enable `useUnifiedTopology`, please remove those options
-    from your [`mongoose.connect()`](/docs/api/mongoose.html#mongoose_Mongoose-connect) or
-    [`createConnection()`](/docs/api/mongoose.html#mongoose_Mongoose-createConnection) calls.
-
-    If you find any unexpected behavior, please [open up an issue on GitHub](https://github.com/Automattic/mongoose/issues/new).
-
-    <h2 id="update"><a href="#update"><code>update()</code></a></h2>
-
-    Like `remove()`, the [`update()` function](/docs/api.html#model_Model.update) is deprecated in favor
-    of the more explicit [`updateOne()`](/docs/api.html#model_Model.updateOne), [`updateMany()`](/docs/api.html#model_Model.updateMany), and [`replaceOne()`](/docs/api.html#model_Model.replaceOne) functions. You should replace
-    `update()` with `updateOne()`, unless you use the [`multi` or `overwrite` options](/docs/api.html#model_Model.update).
-
-    ```
-    collection.update is deprecated. Use updateOne, updateMany, or bulkWrite
-    instead.
-    ```
-
-    ```javascript
-    // Replace this:
-    MyModel.update({ foo: 'bar' }, { answer: 42 });
-    // With this:
-    MyModel.updateOne({ foo: 'bar' }, { answer: 42 });
-
-    // If you use `overwrite: true`, you should use `replaceOne()` instead:
-    MyModel.update(filter, update, { overwrite: true });
-    // Replace with this:
-    MyModel.replaceOne(filter, update);
-
-    // If you use `multi: true`, you should use `updateMany()` instead:
-    MyModel.update(filter, update, { multi: true });
-    // Replace with this:
-    MyModel.updateMany(filter, update);
-    ```
-
-    <h2 id="count"><a href="#count"><code>count()</code></a></h2>
-
-    The MongoDB server has deprecated the `count()` function in favor of two
-    separate functions, [`countDocuments()`](#query_Query-countDocuments) and
-    [`estimatedDocumentCount()`](#query_Query-estimatedDocumentCount).
-
-    ```
-    DeprecationWarning: collection.count is deprecated, and will be removed in a future version. Use collection.countDocuments or collection.estimatedDocumentCount instead
-    ```
-
-    The difference between the two is `countDocuments()` can accept a filter
-    parameter like [`find()`](#query_Query-find). The `estimatedDocumentCount()`
-    function is faster, but can only tell you the total number of documents in
-    a collection. You cannot pass a `filter` to `estimatedDocumentCount()`.
-
-    To migrate, replace `count()` with `countDocuments()` _unless_ you do not
-    pass any arguments to `count()`. If you use `count()` to count all documents
-    in a collection as opposed to counting documents that match a query, use
-    `estimatedDocumentCount()` instead of `countDocuments()`.
-
-    ```javascript
-    // Replace this:
-    MyModel.count({ answer: 42 });
-    // With this:
-    MyModel.countDocuments({ answer: 42 });
-
-    // If you're counting all documents in the collection, use
-    // `estimatedDocumentCount()` instead.
-    MyModel.count();
-    // Replace with:
-    MyModel.estimatedDocumentCount();
-
-    // Replace this:
-    MyModel.find({ answer: 42 }).count().exec();
-    // With this:
-    MyModel.find({ answer: 42 }).countDocuments().exec();
-
-    // Replace this:
-    MyModel.find().count().exec();
-    // With this, since there's no filter
-    MyModel.find().estimatedDocumentCount().exec();
-    ```
-
-    <h2 id="gridstore"><a href="#gridstore"><code>GridStore</code></a></h2>
-
-    If you're using [gridfs-stream](https://www.npmjs.com/package/gridfs-stream),
-    you'll see the below deprecation warning:
-
-    ```
-    DeprecationWarning: GridStore is deprecated, and will be removed in a
-    future version. Please use GridFSBucket instead.
-    ```
-
-    That is because gridfs-stream relies on a [deprecated MongoDB driver class](http://mongodb.github.io/node-mongodb-native/3.1/api/GridStore.html).
-    You should instead use the [MongoDB driver's own streaming API](https://thecodebarbarian.com/mongodb-gridfs-stream).
-
-    ```javascript
-    // Replace this:
-    const conn = mongoose.createConnection('mongodb://localhost:27017/gfstest');
-    const gfs = require('gridfs-store')(conn.db);
-    const writeStream = gfs.createWriteStream({ filename: 'test.dat' });
-
-    // With this:
-    const conn = mongoose.createConnection('mongodb://localhost:27017/gfstest');
-    const gridFSBucket = new mongoose.mongo.GridFSBucket(conn.db);
-    const writeStream = gridFSBucket.openUploadStream('test.dat');
-    ```
diff --git a/docs/enterprise.md b/docs/enterprise.md
new file mode 100644
index 00000000000..3459a8b8933
--- /dev/null
+++ b/docs/enterprise.md
@@ -0,0 +1,71 @@
+# Mongoose for Enterprise
+
+### Available as part of the Tidelift Subscription
+    
+Tidelift is working with the maintainers of Mongoose and thousands of other
+open source projects to deliver commercial support and maintenance for the
+open source dependencies you use to build your applications. Save time,
+reduce risk, and improve code health, while paying the maintainers of the
+exact dependencies you use.
+
+<a href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+  <button style="border-radius: 3px;padding: 3px;padding-left: 30px;padding-right: 30px;border: 1px solid #800;color: #800;">Learn More</button>
+</a>
+<a href="https://tidelift.com/subscription/request-a-demo?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+  <button style="border-radius: 3px;padding: 3px;padding-left: 30px;padding-right: 30px;border: 1px solid transparent;color: white;background-color: #800;">Request a Demo</button>
+</a>
+
+### Enterprise-ready open source software—managed for you
+
+The Tidelift Subscription is a managed open source subscription for application
+dependencies covering millions of open source projects across JavaScript,
+Python, Java, PHP, Ruby, .NET, and more.
+
+Your subscription includes:
+
+- Security updates
+
+Tidelift’s security response team coordinates patches for new breaking security
+vulnerabilities and alerts immediately through a private channel, so your
+software supply chain is always secure.
+
+- Licensing verification and indemnification
+
+Tidelift verifies license information to enable easy policy enforcement and
+adds intellectual property indemnification to cover creators and users in case
+something goes wrong. You always have a 100% up-to-date bill of materials for
+your dependencies to share with your legal team, customers, or partners.
+
+- Maintenance and code improvement
+
+Tidelift ensures the software you rely on keeps working as long as you need it
+to work. Your managed dependencies are actively maintained and we recruit
+additional maintainers where required.
+
+- Package selection and version guidance
+
+We help you choose the best open source packages from the start—and then
+guide you through updates to stay on the best releases as new issues arise.
+
+- Roadmap input
+
+Take a seat at the table with the creators behind the software you use.
+Tidelift’s participating maintainers earn more income as their software is
+used by more subscribers, so they’re interested in knowing what you need.
+
+- Tooling and cloud integration
+
+Tidelift works with GitHub, GitLab, BitBucket, and more. We support every
+cloud platform (and other deployment targets, too).
+
+The end result? All of the capabilities you expect from commercial-grade
+software, for the full breadth of open source you use. That means less time
+grappling with esoteric open source trivia, and more time building your own
+applications—and your business.
+
+<a href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+  <button style="border-radius: 3px;padding: 3px;padding-left: 30px;padding-right: 30px;border: 1px solid #800;color: #800;">Learn More</button>
+</a>
+<a href="https://tidelift.com/subscription/request-a-demo?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
+  <button style="border-radius: 3px;padding: 3px;padding-left: 30px;padding-right: 30px;border: 1px solid transparent;color: white;background-color: #800;">Request a Demo</button>
+</a>
\ No newline at end of file
diff --git a/docs/enterprise.pug b/docs/enterprise.pug
deleted file mode 100644
index 13df7b14d54..00000000000
--- a/docs/enterprise.pug
+++ /dev/null
@@ -1,108 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-  style.
-    button {
-      border-radius: 3px;
-      padding: 3px;
-      padding-left: 30px;
-      padding-right: 30px;
-    }
-
-    button.btn-white {
-      border: 1px solid #800;
-      color: #800;
-    }
-
-    button.btn-color {
-      border: 1px solid transparent;
-      color: white;
-      background-color: #800;
-    }
-
-block content
-  :markdown
-    ## Mongoose for Enterprise
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    ### Available as part of the Tidelift Subscription
-    
-    Tidelift is working with the maintainers of Mongoose and thousands of other
-    open source projects to deliver commercial support and maintenance for the
-    open source dependencies you use to build your applications. Save time,
-    reduce risk, and improve code health, while paying the maintainers of the
-    exact dependencies you use.
-
-    <a href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
-      <button class="btn-white">Learn More</button>
-    </a>
-    <a href="https://tidelift.com/subscription/request-a-demo?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
-      <button class="btn-color">Request a Demo</button>
-    </a>
-
-    ### Enterprise-ready open source software—managed for you
-
-    The Tidelift Subscription is a managed open source subscription for application
-    dependencies covering millions of open source projects across JavaScript,
-    Python, Java, PHP, Ruby, .NET, and more.
-
-    Your subscription includes:
-
-    - Security updates
-
-    Tidelift’s security response team coordinates patches for new breaking security
-    vulnerabilities and alerts immediately through a private channel, so your
-    software supply chain is always secure.
-
-    - Licensing verification and indemnification
-
-    Tidelift verifies license information to enable easy policy enforcement and
-    adds intellectual property indemnification to cover creators and users in case
-    something goes wrong. You always have a 100% up-to-date bill of materials for
-    your dependencies to share with your legal team, customers, or partners.
-
-    - Maintenance and code improvement
-
-    Tidelift ensures the software you rely on keeps working as long as you need it
-    to work. Your managed dependencies are actively maintained and we recruit
-    additional maintainers where required.
-
-    - Package selection and version guidance
-
-    We help you choose the best open source packages from the start—and then
-    guide you through updates to stay on the best releases as new issues arise.
-
-    - Roadmap input
-
-    Take a seat at the table with the creators behind the software you use.
-    Tidelift’s participating maintainers earn more income as their software is
-    used by more subscribers, so they’re interested in knowing what you need.
-
-    - Tooling and cloud integration
-
-    Tidelift works with GitHub, GitLab, BitBucket, and more. We support every
-    cloud platform (and other deployment targets, too).
-
-    The end result? All of the capabilities you expect from commercial-grade
-    software, for the full breadth of open source you use. That means less time
-    grappling with esoteric open source trivia, and more time building your own
-    applications—and your business.
-
-    <a href="https://tidelift.com/subscription/pkg/npm-mongoose?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
-      <button class="btn-white">Learn More</button>
-    </a>
-    <a href="https://tidelift.com/subscription/request-a-demo?utm_source=npm-mongoose&utm_medium=referral&utm_campaign=enterprise">
-      <button class="btn-color">Request a Demo</button>
-    </a>
diff --git a/docs/faq.md b/docs/faq.md
new file mode 100644
index 00000000000..33cc25e3f2e
--- /dev/null
+++ b/docs/faq.md
@@ -0,0 +1,461 @@
+## FAQ
+
+<style>
+hr {
+  display: block;
+  margin-top: 40px;
+  margin-bottom: 40px;
+  border: 0px;
+  height: 1px;
+  background-color: #232323;
+  width: 100%;
+}
+</style>
+
+<hr id="array-changes-not-saved" />
+
+<a href="#array-changes-not-saved">**Q**</a>. Why don't my changes to arrays get saved when I update an element
+    directly?
+
+```javascript
+doc.array[3] = 'changed';
+doc.save();
+```
+
+**A**. Mongoose doesn't create getters/setters for array indexes; without
+them mongoose never gets notified of the change and so doesn't know to
+persist the new value. There are two workarounds:
+[`MongooseArray#set`](./api.html#types_array_MongooseArray.set) or
+[`Document#markModified()`](/docs/api/document.html#document_Document-markModified).
+
+```javascript
+// Saves changes successfully
+doc.array.set(3, 'changed');
+doc.save();
+
+// Also saves changes successfully
+doc.array[3] = 'changed';
+doc.markModified('array');
+doc.save();
+```
+
+This **only** affects when you set an array index directly. If you set
+a path on a document array element, you do not need to use `markModified()`.
+
+```javascript
+// Saves changes successfully without `markModified()`, because this
+// code doesn't set an array index, it sets a path underneath an array index.
+doc.docArray[3].name = 'changed';
+doc.save();
+
+// Does **not** save changes successfully. You need to use `markModified()`
+// or `set()` because this sets an array index.
+doc.docArray[3] = { name: 'changed' };
+doc.save();
+```
+
+<hr id="unique-doesnt-work" />
+
+<a href="#unique-doesnt-work">**Q**</a>. I declared a schema property as `unique` but I can still save duplicates. What gives?
+
+**A**. Mongoose doesn't handle `unique` on its own: `{ name: { type: String, unique: true } }`
+is just a shorthand for creating a [MongoDB unique index on `name`](https://docs.mongodb.com/manual/core/index-unique/).
+For example, if MongoDB doesn't already have a unique index on `name`, the below code will not error despite the fact that `unique` is true.
+
+```javascript
+const schema = new mongoose.Schema({
+  name: { type: String, unique: true }
+});
+const Model = db.model('Test', schema);
+
+Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
+  console.log(err); // No error, unless index was already built
+});
+```
+
+However, if you wait for the index to build using the `Model.on('index')` event, attempts to save duplicates will correctly error.
+
+```javascript
+const schema = new mongoose.Schema({
+  name: { type: String, unique: true }
+});
+const Model = db.model('Test', schema);
+
+Model.on('index', function(err) { // <-- Wait for model's indexes to finish
+  assert.ifError(err);
+  Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
+    console.log(err);
+  });
+});
+
+// Promise based alternative. `init()` returns a promise that resolves
+// when the indexes have finished building successfully. The `init()`
+// function is idempotent, so don't worry about triggering an index rebuild.
+Model.init().then(function() {
+  Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
+    console.log(err);
+  });
+});
+```
+
+MongoDB persists indexes, so you only need to rebuild indexes if you're starting
+with a fresh database or you ran `db.dropDatabase()`. In a production environment,
+you should [create your indexes using the MongoDB shell](https://docs.mongodb.com/manual/reference/method/db.collection.createIndex/)
+rather than relying on mongoose to do it for you. The `unique` option for schemas is
+convenient for development and documentation, but mongoose is *not* an index management solution.
+
+<hr id="nested-properties" />
+
+<a href="#nested-properties">**Q**</a>. When I have a nested property in a schema, mongoose adds empty objects by default. Why?
+
+```javascript
+const schema = new mongoose.Schema({
+  nested: {
+    prop: String
+  }
+});
+const Model = db.model('Test', schema);
+
+// The below prints `{ _id: /* ... */, nested: {} }`, mongoose assigns
+// `nested` to an empty object `{}` by default.
+console.log(new Model());
+```
+
+**A**. This is a performance optimization. These empty objects are not saved
+to the database, nor are they in the result `toObject()`, nor do they show
+up in `JSON.stringify()` output unless you turn off the [`minimize` option](./guide.html#minimize).
+
+The reason for this behavior is that Mongoose's change detection
+and getters/setters are based on [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
+In order to support change detection on nested properties without incurring
+the overhead of running `Object.defineProperty()` every time a document is created,
+mongoose defines properties on the `Model` prototype when the model is compiled.
+Because mongoose needs to define getters and setters for `nested.prop`, `nested`
+must always be defined as an object on a mongoose document, even if `nested`
+is undefined on the underlying [POJO](./guide.html#minimize).
+
+<hr id="destructured-imports" />
+
+<a href="#destructured-imports">**Q**</a>. When I use named imports like `import { set } from 'mongoose'`, I
+    get a `TypeError`. What causes this issue and how can I fix it?
+
+**A**. The only import syntax Mongoose supports is `import mongoose from 'mongoose'`.
+Syntaxes like `import * from 'mongoose'` or `import { model } from 'mongoose'` do **not** work.
+The global Mongoose object stores types, [global options](/docs/api.html#mongoose_Mongoose-set), and other important
+properties that Mongoose needs. When you do `import { model } from 'mongoose'`, the
+`this` value in `model()` is not the Mongoose global.
+
+```javascript
+// file1.js
+exports.answer = 42;
+exports.foo = function() { console.log(this.answer); };
+
+// file2.js
+const obj = require('./file1');
+obj.foo(); // "42"
+
+// file3.js
+const { foo } = require('./file1');
+foo(); // "undefined"
+```
+
+<hr id="arrow-functions" />
+
+<a href="#arrow-functions">**Q**</a>. I'm using an arrow function for a [virtual](./guide.html#virtuals), [middleware](./middleware.html), [getter](./api.html#schematype_SchemaType-get)/[setter](./api.html#schematype_SchemaType-set), or [method](./guide.html#methods) and the value of `this` is wrong.
+
+**A**. Arrow functions [handle the `this` keyword much differently than conventional functions](https://masteringjs.io/tutorials/fundamentals/arrow#why-not-arrow-functions).
+Mongoose getters/setters depend on `this` to give you access to the document that you're writing to, but this functionality does not work with arrow functions. Do **not** use arrow functions for mongoose getters/setters unless do not intend to access the document in the getter/setter.
+
+```javascript
+// Do **NOT** use arrow functions as shown below unless you're certain
+// that's what you want. If you're reading this FAQ, odds are you should
+// just be using a conventional function.
+const schema = new mongoose.Schema({
+  propWithGetter: {
+    type: String,
+    get: v => {
+      // Will **not** be the doc, do **not** use arrow functions for getters/setters
+      console.log(this);
+      return v;
+    }
+  }
+});
+
+// `this` will **not** be the doc, do **not** use arrow functions for methods
+schema.method.arrowMethod = () => this;
+schema.virtual('virtualWithArrow').get(() => {
+  // `this` will **not** be the doc, do **not** use arrow functions for virtuals
+  console.log(this);
+});
+```
+
+<hr id="type-key">
+
+<a href="#type-key">**Q**</a>. I have an embedded property named `type` like this:
+
+```javascript
+const holdingSchema = new Schema({
+  // You might expect `asset` to be an object that has 2 properties,
+  // but unfortunately `type` is special in mongoose so mongoose
+  // interprets this schema to mean that `asset` is a string
+  asset: {
+    type: String,
+    ticker: String
+  }
+});
+```
+
+But mongoose gives me a CastError telling me that it can't cast an object
+to a string when I try to save a `Holding` with an `asset` object. Why
+is this?
+
+```javascript
+Holding.create({ asset: { type: 'stock', ticker: 'MDB' } }).catch(error => {
+  // Cast to String failed for value "{ type: 'stock', ticker: 'MDB' }" at path "asset"
+  console.error(error);
+});
+```
+
+**A**. The `type` property is special in mongoose, so when you say
+`type: String`, mongoose interprets it as a type declaration. In the
+above schema, mongoose thinks `asset` is a string, not an object. Do
+this instead:
+
+```javascript
+const holdingSchema = new Schema({
+  // This is how you tell mongoose you mean `asset` is an object with
+  // a string property `type`, as opposed to telling mongoose that `asset`
+  // is a string.
+  asset: {
+    type: { type: String },
+    ticker: String
+  }
+});
+```
+
+<hr id="populate_sort_order" />
+
+<a href="#populate_sort_order">**Q**</a>. I'm populating a nested property under an array like the below code:
+
+```javascript
+new Schema({
+  arr: [{
+    child: { ref: 'OtherModel', type: Schema.Types.ObjectId }
+  }]
+});
+```
+
+`.populate({ path: 'arr.child', options: { sort: 'name' } })` won't sort by `arr.child.name`?
+
+**A**. See [this GitHub issue](https://github.com/Automattic/mongoose/issues/2202). It's a known issue but one that's exceptionally difficult to fix.
+
+<hr id="model_functions_hanging" />
+
+<a href="#model_functions_hanging">**Q**</a>. All function calls on my models hang, what am I doing wrong?
+
+**A**. By default, mongoose will buffer your function calls until it can
+connect to MongoDB. Read the [buffering section of the connection docs](./connections.html#buffering)
+for more information.
+
+<hr id="enable_debugging" />
+
+<a href="#enable_debugging">**Q**</a>. How can I enable debugging?
+
+**A**. Set the `debug` option:
+
+```javascript
+// all executed methods log output to console
+mongoose.set('debug', true)
+    
+// disable colors in debug mode
+mongoose.set('debug', { color: false })
+
+// get mongodb-shell friendly output (ISODate)
+mongoose.set('debug', { shell: true })
+```
+
+For more debugging options (streams, callbacks), see the ['debug' option under `.set()`](./api.html#mongoose_Mongoose-set).
+
+<hr id="callback_never_executes" />
+
+<a href="#callback_never_executes">**Q**</a>. My `save()` callback never executes. What am I doing wrong?
+
+**A**. All `collection` actions (insert, remove, queries, etc.) are queued
+until Mongoose successfully connects to MongoDB. It is likely you haven't called Mongoose's
+`connect()` or `createConnection()` function yet.
+
+In Mongoose 5.11, there is a `bufferTimeoutMS` option (set to 10000 by default) that configures how long
+Mongoose will allow an operation to stay buffered before throwing an error.
+
+If you want to opt out of Mongoose's buffering mechanism across your entire
+application, set the global `bufferCommands` option to false:
+
+```javascript
+mongoose.set('bufferCommands', false);
+```
+
+Instead of opting out of Mongoose's buffering mechanism, you may want to instead reduce `bufferTimeoutMS`
+to make Mongoose only buffer for a short time.
+
+```javascript
+// If an operation is buffered for more than 500ms, throw an error.
+mongoose.set('bufferTimeoutMS', 500);
+```
+
+<hr id="creating_connections" />
+
+<a href="#creating_connections">**Q**</a>. Should I create/destroy a new connection for each database operation?
+
+**A**. No. Open your connection when your application starts up and leave
+it open until the application shuts down.
+
+<hr id="overwrite-model-error" />
+
+<a href="#overwrite-model-error">**Q**</a>. Why do I get "OverwriteModelError: Cannot overwrite .. model once
+compiled" when I use nodemon / a testing framework?
+
+**A**. `mongoose.model('ModelName', schema)` requires 'ModelName' to be
+unique, so you can access the model by using `mongoose.model('ModelName')`.
+If you put `mongoose.model('ModelName', schema);` in a
+[mocha `beforeEach()` hook](https://mochajs.org/#hooks), this code will
+attempt to create a new model named 'ModelName' before **every** test,
+and so you will get an error. Make sure you only create a new model with
+a given name **once**. If you need to create multiple models with the
+same name, create a new connection and bind the model to the connection.
+
+```javascript
+const mongoose = require('mongoose');
+const connection = mongoose.createConnection(..);
+
+// use mongoose.Schema
+const kittySchema = mongoose.Schema({ name: String });
+
+// use connection.model
+const Kitten = connection.model('Kitten', kittySchema);
+```
+
+<hr id="array-defaults" />
+
+<a href="#array-defaults">**Q**</a>. How can I change mongoose's default behavior of initializing an array path to an empty array so that I can require real data on document creation?
+
+**A**. You can set the default of the array to a function that returns `undefined`.
+
+```javascript
+const CollectionSchema = new Schema({
+  field1: {
+    type: [String],
+    default: void 0
+  }
+});
+```
+
+<hr id="initialize-array-path-null" />
+    
+<a href="#initialize-array-path-null">**Q**</a>. How can I initialize an array path to `null`?
+
+**A**. You can set the default of the array to a function that returns `null`.
+
+```javascript
+const CollectionSchema = new Schema({
+  field1: {
+    type: [String],
+    default: () => { return null; }
+  }
+});
+```
+
+<hr id="aggregate-casting" />
+
+<a href="#aggregate-casting">**Q**</a>. Why does my aggregate $match fail to return the document that my find query returns when working with dates?
+
+**A**. Mongoose does not cast aggregation pipeline stages because with $project,
+$group, etc. the type of a property may change during the aggregation. If you want
+to query by date using the aggregation framework, you're responsible for ensuring
+that you're passing in a valid date.
+
+<hr id="date_changes" />
+
+<a href="#date_changes">**Q**</a>. Why don't in-place modifications to date objects
+(e.g. `date.setMonth(1);`) get saved?
+
+```javascript
+doc.createdAt.setDate(2011, 5, 1);
+doc.save(); // createdAt changes won't get saved!
+```
+
+**A**. Mongoose currently doesn't watch for in-place updates to date
+objects. If you have need for this feature, feel free to discuss on
+[this GitHub issue](https://github.com/Automattic/mongoose/issues/3738).
+There are several workarounds:
+
+```javascript
+doc.createdAt.setDate(2011, 5, 1);
+doc.markModified('createdAt');
+doc.save(); // Works
+
+doc.createdAt = new Date(2011, 5, 1).setHours(4);
+doc.save(); // Works
+```
+
+<hr id="parallel_saves" />
+
+<a href="#parallel_saves">**Q**</a>. Why does calling `save()` multiple times on the same document in parallel only let
+the first save call succeed and return ParallelSaveErrors for the rest?
+
+**A**. Due to the asynchronous nature of validation and middleware in general, calling
+`save()` multiple times in parallel on the same doc could result in conflicts. For example,
+validating, and then subsequently invalidating the same path.
+
+<hr id="objectid-validation" />
+
+<a href="#objectid-validation">**Q**</a>. Why is **any** 12 character string successfully cast to an ObjectId?
+
+**A**. Technically, any 12 character string is a valid [ObjectId](https://docs.mongodb.com/manual/reference/bson-types/#objectid).
+Consider using a regex like `/^[a-f0-9]{24}$/` to test whether a string is exactly 24 hex characters.
+
+<hr id="map-keys-strings" />
+
+<a href="#map-keys-strings">**Q**</a>. Why do keys in Mongoose Maps have to be strings?
+
+**A**. Because the Map eventually gets stored in MongoDB where the keys must be strings.
+
+<hr id="limit-vs-perDocumentLimit" />
+
+<a href="#limit-vs-perDocumentLimit">**Q**</a>. I am using `Model.find(...).populate(...)` with the `limit` option, but getting fewer results than the limit. What gives?
+
+**A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose
+instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the
+[perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in
+mind that populate() will execute a separate query for each document.
+
+<hr id="duplicate-query" />
+
+<a href="#duplicate-query">**Q**</a>. My query/update seems to execute twice. Why is this happening?
+
+**A**. The most common cause of duplicate queries is **mixing callbacks and promises with queries**.
+That's because passing a callback to a query function, like `find()` or `updateOne()`,
+immediately executes the query, and calling [`then()`](https://masteringjs.io/tutorials/fundamentals/then)
+executes the query again.
+
+Mixing promises and callbacks can lead to duplicate entries in arrays.
+For example, the below code inserts 2 entries into the `tags` array, **not* just 1.
+
+```javascript
+const BlogPost = mongoose.model('BlogPost', new Schema({
+  title: String,
+  tags: [String]
+}));
+
+// Because there's both `await` **and** a callback, this `updateOne()` executes twice
+// and thus pushes the same string into `tags` twice.
+const update = { $push: { tags: ['javascript'] } };
+await BlogPost.updateOne({ title: 'Introduction to Promises' }, update, (err, res) => {
+  console.log(res);
+});
+```
+
+<hr id="add_something" />
+
+**Something to add?**
+
+If you'd like to contribute to this page, please [visit it](https://github.com/Automattic/mongoose/tree/master/docs/faq.md) on github and use the [Edit](https://github.com/blog/844-forking-with-the-edit-button) button to send a pull request.
\ No newline at end of file
diff --git a/docs/faq.pug b/docs/faq.pug
deleted file mode 100644
index 29ef6affbd2..00000000000
--- a/docs/faq.pug
+++ /dev/null
@@ -1,501 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block append style
-  style.
-    hr {
-      display: block;
-      margin-top: 40px;
-      margin-bottom: 40px;
-      border: 0px;
-      height: 1px;
-      background-color: #232323;
-      width: 100%;
-    }
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## FAQ
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-
-    <hr id="array-changes-not-saved" />
-
-    <a href="#array-changes-not-saved">**Q**</a>. Why don't my changes to arrays get saved when I update an element
-    directly?
-
-    ```javascript
-    doc.array[3] = 'changed';
-    doc.save();
-    ```
-
-    **A**. Mongoose doesn't create getters/setters for array indexes; without
-    them mongoose never gets notified of the change and so doesn't know to
-    persist the new value. There are two workarounds:
-    [`MongooseArray#set`](./api.html#types_array_MongooseArray.set) or
-    [`Document#markModified()`](/docs/api/document.html#document_Document-markModified).
-
-    ```javascript
-    // Saves changes successfully
-    doc.array.set(3, 'changed');
-    doc.save();
-
-    // Also saves changes successfully
-    doc.array[3] = 'changed';
-    doc.markModified('array');
-    doc.save();
-    ```
-
-    This **only** affects when you set an array index directly. If you set
-    a path on a document array element, you do not need to use `markModified()`.
-
-    ```javascript
-    // Saves changes successfully without `markModified()`, because this
-    // code doesn't set an array index, it sets a path underneath an array index.
-    doc.docArray[3].name = 'changed';
-    doc.save();
-
-    // Does **not** save changes successfully. You need to use `markModified()`
-    // or `set()` because this sets an array index.
-    doc.docArray[3] = { name: 'changed' };
-    doc.save();
-    ```
-
-
-    <hr id="unique-doesnt-work" />
-
-    <a href="#unique-doesnt-work">**Q**</a>. I declared a schema property as `unique` but I can still save
-    duplicates. What gives?
-
-    **A**. Mongoose doesn't handle `unique` on its own: `{ name: { type: String, unique: true } }`
-    is just a shorthand for creating a [MongoDB unique index on `name`](https://docs.mongodb.com/manual/core/index-unique/).
-    For example, if MongoDB doesn't already have a unique index on `name`, the below code will not error despite the fact that `unique` is true.
-
-    ```javascript
-    const schema = new mongoose.Schema({
-      name: { type: String, unique: true }
-    });
-    const Model = db.model('Test', schema);
-
-    Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
-      console.log(err); // No error, unless index was already built
-    });
-    ```
-
-    However, if you wait for the index to build using the `Model.on('index')` event, attempts to save duplicates will correctly error.
-
-    ```javascript
-    const schema = new mongoose.Schema({
-      name: { type: String, unique: true }
-    });
-    const Model = db.model('Test', schema);
-
-    Model.on('index', function(err) { // <-- Wait for model's indexes to finish
-      assert.ifError(err);
-      Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
-        console.log(err);
-      });
-    });
-
-    // Promise based alternative. `init()` returns a promise that resolves
-    // when the indexes have finished building successfully. The `init()`
-    // function is idempotent, so don't worry about triggering an index rebuild.
-    Model.init().then(function() {
-      Model.create([{ name: 'Val' }, { name: 'Val' }], function(err) {
-        console.log(err);
-      });
-    });
-    ```
-
-    MongoDB persists indexes, so you only need to rebuild indexes if you're starting
-    with a fresh database or you ran `db.dropDatabase()`. In a production environment,
-    you should [create your indexes using the MongoDB shell](https://docs.mongodb.com/manual/reference/method/db.collection.createIndex/)
-    rather than relying on mongoose to do it for you. The `unique` option for schemas is
-    convenient for development and documentation, but mongoose is *not* an index management solution.
-
-
-    <hr id="nested-properties" />
-
-    <a href="#nested-properties">**Q**</a>. When I have a nested property in a schema, mongoose adds empty objects by default. Why?
-
-    ```javascript
-    const schema = new mongoose.Schema({
-      nested: {
-        prop: String
-      }
-    });
-    const Model = db.model('Test', schema);
-
-    // The below prints `{ _id: /* ... */, nested: {} }`, mongoose assigns
-    // `nested` to an empty object `{}` by default.
-    console.log(new Model());
-    ```
-
-    **A**. This is a performance optimization. These empty objects are not saved
-    to the database, nor are they in the result `toObject()`, nor do they show
-    up in `JSON.stringify()` output unless you turn off the [`minimize` option](./guide.html#minimize).
-
-    The reason for this behavior is that Mongoose's change detection
-    and getters/setters are based on [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
-    In order to support change detection on nested properties without incurring
-    the overhead of running `Object.defineProperty()` every time a document is created,
-    mongoose defines properties on the `Model` prototype when the model is compiled.
-    Because mongoose needs to define getters and setters for `nested.prop`, `nested`
-    must always be defined as an object on a mongoose document, even if `nested`
-    is undefined on the underlying [POJO](./guide.html#minimize).
-
-
-    <hr id="destructured-imports" />
-
-    <a href="#destructured-imports">**Q**</a>. When I use named imports like `import { set } from 'mongoose'`, I
-    get a `TypeError`. What causes this issue and how can I fix it?
-
-    **A**. The only import syntax Mongoose supports is `import mongoose from 'mongoose'`.
-    Syntaxes like `import * from 'mongoose'` or `import { model } from 'mongoose'` do **not** work.
-    The global Mongoose object stores types, [global options](/docs/api.html#mongoose_Mongoose-set), and other important
-    properties that Mongoose needs. When you do `import { model } from 'mongoose'`, the
-    `this` value in `model()` is not the Mongoose global.
-
-    ```javascript
-    // file1.js
-    exports.answer = 42;
-    exports.foo = function() { console.log(this.answer); };
-
-    // file2.js
-    const obj = require('./file1');
-    obj.foo(); // "42"
-
-    // file3.js
-    const { foo } = require('./file1');
-    foo(); // "undefined"
-    ```
-
-
-    <hr id="arrow-functions" />
-
-    <a href="#arrow-functions">**Q**</a>. I'm using an arrow function for a [virtual](./guide.html#virtuals), [middleware](./middleware.html), [getter](./api.html#schematype_SchemaType-get)/[setter](./api.html#schematype_SchemaType-set), or [method](./guide.html#methods) and the value of `this` is wrong.
-
-    **A**. Arrow functions [handle the `this` keyword much differently than conventional functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this).
-    Mongoose getters/setters depend on `this` to give you access to the document that you're writing to, but this functionality does not work with arrow functions. Do **not** use arrow functions for mongoose getters/setters unless do not intend to access the document in the getter/setter.
-
-    ```javascript
-    // Do **NOT** use arrow functions as shown below unless you're certain
-    // that's what you want. If you're reading this FAQ, odds are you should
-    // just be using a conventional function.
-    const schema = new mongoose.Schema({
-      propWithGetter: {
-        type: String,
-        get: v => {
-          // Will **not** be the doc, do **not** use arrow functions for getters/setters
-          console.log(this);
-          return v;
-        }
-      }
-    });
-
-    // `this` will **not** be the doc, do **not** use arrow functions for methods
-    schema.method.arrowMethod = () => this;
-    schema.virtual('virtualWithArrow').get(() => {
-      // `this` will **not** be the doc, do **not** use arrow functions for virtuals
-      console.log(this);
-    });
-    ```
-
-
-    <hr id="type-key">
-
-    <a href="#type-key">**Q**</a>. I have an embedded property named `type` like this:
-
-    ```javascript
-    const holdingSchema = new Schema({
-      // You might expect `asset` to be an object that has 2 properties,
-      // but unfortunately `type` is special in mongoose so mongoose
-      // interprets this schema to mean that `asset` is a string
-      asset: {
-        type: String,
-        ticker: String
-      }
-    });
-    ```
-
-    But mongoose gives me a CastError telling me that it can't cast an object
-    to a string when I try to save a `Holding` with an `asset` object. Why
-    is this?
-
-    ```javascript
-    Holding.create({ asset: { type: 'stock', ticker: 'MDB' } }).catch(error => {
-      // Cast to String failed for value "{ type: 'stock', ticker: 'MDB' }" at path "asset"
-      console.error(error);
-    });
-    ```
-
-    **A**. The `type` property is special in mongoose, so when you say
-    `type: String`, mongoose interprets it as a type declaration. In the
-    above schema, mongoose thinks `asset` is a string, not an object. Do
-    this instead:
-
-    ```javascript
-    const holdingSchema = new Schema({
-      // This is how you tell mongoose you mean `asset` is an object with
-      // a string property `type`, as opposed to telling mongoose that `asset`
-      // is a string.
-      asset: {
-        type: { type: String },
-        ticker: String
-      }
-    });
-    ```
-
-
-    <hr id="populate_sort_order" />
-
-    <a href="#populate_sort_order">**Q**</a>. I'm populating a nested property under an array like the below code:
-
-    ```javascript
-      new Schema({
-        arr: [{
-          child: { ref: 'OtherModel', type: Schema.Types.ObjectId }
-        }]
-      });
-    ```
-
-    `.populate({ path: 'arr.child', options: { sort: 'name' } })` won't sort
-    by `arr.child.name`?
-
-    **A**. See [this GitHub issue](https://github.com/Automattic/mongoose/issues/2202). It's a known issue but one that's exceptionally difficult to fix.
-
-    <hr id="model_functions_hanging" />
-
-    <a href="#model_functions_hanging">**Q**</a>. All function calls on my models hang, what am I doing wrong?
-
-    **A**. By default, mongoose will buffer your function calls until it can
-    connect to MongoDB. Read the [buffering section of the connection docs](./connections.html#buffering)
-    for more information.
-
-
-    <hr id="enable_debugging" />
-
-    <a href="#enable_debugging">**Q**</a>. How can I enable debugging?
-
-    **A**. Set the `debug` option:
-
-    ```javascript
-    // all executed methods log output to console
-    mongoose.set('debug', true)
-    
-    // disable colors in debug mode
-    mongoose.set('debug', { color: false })
-
-    // get mongodb-shell friendly output (ISODate)
-    mongoose.set('debug', { shell: true })
-    ```
-
-    For more debugging options (streams, callbacks), see the ['debug' option under `.set()`](./api.html#mongoose_Mongoose-set).
-
-
-    <hr id="callback_never_executes" />
-
-    <a href="#callback_never_executes">**Q**</a>. My `save()` callback never executes. What am I doing wrong?
-
-    **A**. All `collection` actions (insert, remove, queries, etc.) are queued
-    until Mongoose successfully connects to MongoDB. It is likely you haven't called Mongoose's
-    `connect()` or `createConnection()` function yet.
-
-    In Mongoose 5.11, there is a `bufferTimeoutMS` option (set to 10000 by default) that configures how long
-    Mongoose will allow an operation to stay buffered before throwing an error.
-
-    If you want to opt out of Mongoose's buffering mechanism across your entire
-    application, set the global `bufferCommands` option to false:
-
-    ```javascript
-    mongoose.set('bufferCommands', false);
-    ```
-
-    Instead of opting out of Mongoose's buffering mechanism, you may want to instead reduce `bufferTimeoutMS`
-    to make Mongoose only buffer for a short time.
-
-    ```javascript
-    // If an operation is buffered for more than 500ms, throw an error.
-    mongoose.set('bufferTimeoutMS', 500);
-    ```
-
-    <hr id="creating_connections" />
-
-    <a href="#creating_connections">**Q**</a>. Should I create/destroy a new connection for each database operation?
-
-    **A**. No. Open your connection when your application starts up and leave
-    it open until the application shuts down.
-
-
-    <hr id="overwrite-model-error" />
-
-    <a href="#overwrite-model-error">**Q**</a>. Why do I get "OverwriteModelError: Cannot overwrite .. model once
-    compiled" when I use nodemon / a testing framework?
-
-    **A**. `mongoose.model('ModelName', schema)` requires 'ModelName' to be
-    unique, so you can access the model by using `mongoose.model('ModelName')`.
-    If you put `mongoose.model('ModelName', schema);` in a
-    [mocha `beforeEach()` hook](https://mochajs.org/#hooks), this code will
-    attempt to create a new model named 'ModelName' before **every** test,
-    and so you will get an error. Make sure you only create a new model with
-    a given name **once**. If you need to create multiple models with the
-    same name, create a new connection and bind the model to the connection.
-
-    ```javascript
-    const mongoose = require('mongoose');
-    const connection = mongoose.createConnection(..);
-
-    // use mongoose.Schema
-    const kittySchema = mongoose.Schema({ name: String });
-
-    // use connection.model
-    const Kitten = connection.model('Kitten', kittySchema);
-    ```
-
-
-    <hr id="array-defaults" />
-
-    <a href="#array-defaults">**Q**</a>. How can I change mongoose's default behavior of initializing an array
-    path to an empty array so that I can require real data on document creation?
-
-    **A**. You can set the default of the array to a function that returns `undefined`.
-    ```javascript
-    const CollectionSchema = new Schema({
-      field1: {
-        type: [String],
-        default: void 0
-      }
-    });
-    ```
-
-
-    <hr id="initialize-array-path-null" />
-    
-    <a href="#initialize-array-path-null">**Q**</a>. How can I initialize an array path to `null`?
-
-    **A**. You can set the default of the array to a function that returns `null`.
-    ```javascript
-    const CollectionSchema = new Schema({
-      field1: {
-        type: [String],
-        default: () => { return null; }
-      }
-    });
-    ```
-
-    <hr id="aggregate-casting" />
-
-    <a href="#aggregate-casting">**Q**</a>. Why does my aggregate $match fail to return the document that my find query
-    returns when working with dates?
-
-    **A**. Mongoose does not cast aggregation pipeline stages because with $project,
-    $group, etc. the type of a property may change during the aggregation. If you want
-    to query by date using the aggregation framework, you're responsible for ensuring
-    that you're passing in a valid date.
-
-
-    <hr id="date_changes" />
-
-    <a href="#date_changes">**Q**</a>. Why don't in-place modifications to date objects
-    (e.g. `date.setMonth(1);`) get saved?
-
-    ```javascript
-    doc.createdAt.setDate(2011, 5, 1);
-    doc.save(); // createdAt changes won't get saved!
-    ```
-
-    **A**. Mongoose currently doesn't watch for in-place updates to date
-    objects. If you have need for this feature, feel free to discuss on
-    [this GitHub issue](https://github.com/Automattic/mongoose/issues/3738).
-    There are several workarounds:
-
-    ```javascript
-    doc.createdAt.setDate(2011, 5, 1);
-    doc.markModified('createdAt');
-    doc.save(); // Works
-
-    doc.createdAt = new Date(2011, 5, 1).setHours(4);
-    doc.save(); // Works
-    ```
-
-    <hr id="parallel_saves" />
-
-    <a href="#parallel_saves">**Q**</a>. Why does calling `save()` multiple times on the same document in parallel only let
-    the first save call succeed and return ParallelSaveErrors for the rest?
-
-    **A**. Due to the asynchronous nature of validation and middleware in general, calling
-    `save()` multiple times in parallel on the same doc could result in conflicts. For example,
-    validating, and then subsequently invalidating the same path.
-
-    <hr id="objectid-validation" />
-
-    <a href="#objectid-validation">**Q**</a>. Why is **any** 12 character string successfully cast to an ObjectId?
-
-    **A**. Technically, any 12 character string is a valid [ObjectId](https://docs.mongodb.com/manual/reference/bson-types/#objectid).
-    Consider using a regex like `/^[a-f0-9]{24}$/` to test whether a string is exactly 24 hex characters.
-
-
-    <hr id="map-keys-strings" />
-
-    <a href="#map-keys-strings">**Q**</a>. Why do keys in Mongoose Maps have to be strings?
-
-    **A**. Because the Map eventually gets stored in MongoDB where the keys must be strings.
-
-    <hr id="limit-vs-perDocumentLimit" />
-
-    <a href="#limit-vs-perDocumentLimit">**Q**</a>. I am using `Model.find(...).populate(...)` with the `limit` option, but getting fewer results than the limit. What gives?
-
-    **A**. In order to avoid executing a separate query for each document returned from the `find` query, Mongoose
-    instead queries using (numDocuments * limit) as the limit. If you need the correct limit, you should use the
-    [perDocumentLimit](/docs/populate.html#limit-vs-perDocumentLimit) option (new in Mongoose 5.9.0). Just keep in
-    mind that populate() will execute a separate query for each document.
-
-    <hr id="duplicate-query" />
-
-    <a href="#duplicate-query">**Q**</a>. My query/update seems to execute twice. Why is this happening?
-
-    **A**. The most common cause of duplicate queries is **mixing callbacks and promises with queries**.
-    That's because passing a callback to a query function, like `find()` or `updateOne()`,
-    immediately executes the query, and calling [`then()`](https://masteringjs.io/tutorials/fundamentals/then)
-    executes the query again.
-
-    Mixing promises and callbacks can lead to duplicate entries in arrays.
-    For example, the below code inserts 2 entries into the `tags` array, **not* just 1.
-
-    ```javascript
-    const BlogPost = mongoose.model('BlogPost', new Schema({
-      title: String,
-      tags: [String]
-    }));
-
-    // Because there's both `await` **and** a callback, this `updateOne()` executes twice
-    // and thus pushes the same string into `tags` twice.
-    const update = { $push: { tags: ['javascript'] } };
-    await BlogPost.updateOne({ title: 'Introduction to Promises' }, update, (err, res) => {
-      console.log(res);
-    });
-    ```
-
-    <hr id="add_something" />
-
-    **Something to add?**
-
-    If you'd like to contribute to this page, please
-    [visit it](https://github.com/Automattic/mongoose/tree/master/docs/faq.pug)
-    on github and use the [Edit](https://github.com/blog/844-forking-with-the-edit-button) button to send a pull request.
diff --git a/docs/further_reading.md b/docs/further_reading.md
new file mode 100644
index 00000000000..fd8b4a13001
--- /dev/null
+++ b/docs/further_reading.md
@@ -0,0 +1,208 @@
+## Further Reading
+
+<style>
+  img { width: auto; }
+
+  .pluralsight-link {
+    float: left;
+    margin-right: 0.5em;
+  }
+
+  .pluralsight-title {
+    font-size: 1.5em;
+  }
+
+  p {
+    line-height: 1.5em;
+  }
+</style>
+
+There's a lot of great content out there to learn more about Mongoose.
+This page has a list of video courses, books, and blog posts curated by
+Mongoose maintainers. We've gone through every course, book, and article
+on this page to make sure it is high quality.
+
+* [Video Courses](#video-courses)
+* [Books](#books)
+* [Blog Posts](#blog-posts)
+
+## Video Courses
+
+<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
+  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
+</a>
+<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
+    
+<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fapi-design-nodejs-express-mongo%2Ftable-of-contents">
+  API Design in Node.js Featuring Express & Mongo
+</a>
+
+This course is a great introduction to building a RESTful API with [Express](http://expressjs.com/)
+and Mongoose. The instructor is [Scott Moss](https://frontendmasters.com/teachers/scott-moss/),
+a serial entrepreneur and former intructor at [Hack Reactor](https://www.hackreactor.com/), San Francisco's number one coding bootcamp.
+
+<div style="clear: both"></div>
+<br><br>
+
+<a href="https://thinkster.io/tutorials/node-json-api" class="pluralsight-link" style="padding:20px">
+  <img src="https://pbs.twimg.com/profile_images/819400302864412676/6x2g2XtJ_400x400.jpg" border="0" alt="" style="width: 140px" />
+</a>
+  
+<a class="pluralsight-title" href="https://thinkster.io/tutorials/node-json-api">
+  Building a Production Ready Node.js JSON API
+</a>
+
+<br><br>
+
+[Thinkster](https://thinkster.io/) has created a full stack web
+development course for just about every backend and frontend framework
+you can think of. Want to learn how to build a full stack app with Vue
+and Django, or with Angular and Rails? Thinkster has a course for that.
+The Node.js tutorial walks you through building a production-ready
+RESTful API with Express and Mongoose from scratch.
+
+<div style="clear: both"></div>
+<br><br>
+
+<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
+  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
+</a>
+<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
+
+<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoose-for-nodejs-mongodb%2Ftable-of-contents">
+  Introduction to Mongoose for Node.js and MongoDB
+</a>
+
+<br><br>
+
+Know someone who wants to get started building Node.js apps but doesn't have
+a lot of software development experience?
+This course is more beginner-friendly than _API Design_ and is a great
+resource for beginners looking to get started.
+
+<div style="clear: both"></div>
+<br><br>
+
+<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
+  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
+</a>
+<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
+
+<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">
+  RESTful Web Services with Node.js and Express
+</a>
+
+<br><br>
+
+Looking for a course to take you from zero to Express + Mongoose
+REST API fast? This is the one. This course is halfway
+between _API Design_ and _Introduction to Mongoose_. It focuses more on
+[Express](http://expressjs.com/), but also doesn't go into as much detail as _API Design_. 
+
+<div style="clear: both"></div>
+<br><br>
+
+<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
+  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
+</a>
+<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
+
+<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fbuilding-business-applications-vuejs%2Ftable-of-contents">
+  Building Business Applications with Vue.js and MongoDB
+</a>
+
+<br><br>
+
+This course walks you through building a full-stack web application using
+the [VENoM Stack](https://medium.com/@audretschjames/venom-stack-docker-setup-for-local-development-457093761ad1).
+Try this course if you're a [Vue.js](https://vuejs.org/) expert looking to
+expand into backend engineering or an experienced MongoDB dev looking to
+learn about frontend dev.
+
+<div style="clear: both"></div>
+<br><br>
+
+<a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
+  <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
+</a>
+<img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
+
+<a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoosejs-moving-forward%2Ftable-of-contents">
+  Moving Forward with Mongoose.js
+</a>
+
+<br><br>
+
+Stuck maintaining a legacy codebase on Mongoose 3.x? This course will
+give you a detailed overview of the [breaking changes and new features in Mongoose 4.x](https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes),
+so you can upgrade with confidence.
+
+<div style="clear: both"></div>
+
+## Books
+
+<a class="pluralsight-link" href="http://bit.ly/mongoose-book-2013">
+  <img src="https://s3.amazonaws.com/codebarbarian-images/mongoose.jpg" style="width: 180px">
+</a>
+
+<a class="pluralsight-title" href="http://bit.ly/mongoose-book-2013">
+  <i>Mongoose for Application Development</i> by Simon Holmes
+</a>
+
+This is the book on Mongoose. Even though it is from 2013,
+_Mongoose for Application Development_ has stood the test of time. This
+book does an excellent job summarizing the core ideas that make Mongoose so
+powerful. Just sub out callbacks for promises.
+
+<div style="clear: both"></div>
+
+<a class="pluralsight-link" href="https://bit.ly/mongodb-schema-design">
+  <img src="https://s3.amazonaws.com/codebarbarian-images/schemadesign.jpg" style="width: 180px">
+</a>
+
+<a class="pluralsight-title" href="https://bit.ly/mongodb-schema-design">
+  <i>The Little MongoDB Schema Design Book</i> by Christian Kvalheim
+</a>
+
+Christian Kvalheim originally wrote the MongoDB Node.js driver in early 2010,
+and maintained the driver almost singlehandedly until 2017. As maintainer
+of the Node.js driver, Christian saw more Node.js+MongoDB code bases than
+anyone, and his experience is unmatched.
+This book distills 6 years of hard-learned lessons into concrete examples
+of how to design MongoDB schemas for massive scale. If you want to learn
+how to structure MongoDB schemas for an ecommerce store, a category tree, or a
+blog that can support hundreds of millions of requests per day, this is
+the book for you.
+
+<div style="clear: both"></div>
+
+## Blog Posts
+
+<a class="pluralsight-link" style="padding: 20px" href="https://medium.freecodecamp.org/introduction-to-mongoose-for-mongodb-d2a7aa593c57">
+  <img src="https://cdn-images-1.medium.com/max/800/1*uTZXsVta4TwghNobMkZeZg.png" style="width: 140px">
+</a>
+
+<a class="pluralsight-title" href="https://medium.freecodecamp.org/introduction-to-mongoose-for-mongodb-d2a7aa593c57">
+  <i>Introduction to Mongoose for MongoDB</i> on freeCodeCamp
+</a>
+
+Coming from an SQL background and having trouble understanding Mongoose and MongoDB?
+This article explains the core concepts of Mongoose with references to similar
+concepts in SQL.
+
+<div style="clear: both"></div>
+
+<a class="pluralsight-link" style="padding: 20px" href="https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/mongoose">
+  <img src="https://developer.mozilla.org/static/img/opengraph-logo.72382e605ce3.png" style="width: 140px">
+</a>
+
+<a class="pluralsight-title" href="https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/mongoose">
+  <i>Express Tutorial Part 3: Using a Database (with Mongoose)</i> on Mozilla Developer Network
+</a>
+
+Virtually every JavaScript developer has read MDN docs. They're usually one
+of the top 3 results when you Google "javascript startswith" or any other
+core JavaScript function. This tutorial provides an overview of Mongoose
+in MDN's standard style and tone.
+
+<div style="clear: both"></div>
\ No newline at end of file
diff --git a/docs/further_reading.pug b/docs/further_reading.pug
deleted file mode 100644
index 17165a16761..00000000000
--- a/docs/further_reading.pug
+++ /dev/null
@@ -1,229 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-  style.
-    img { width: auto; }
-
-    .pluralsight-link {
-      float: left;
-      margin-right: 0.5em;
-    }
-
-    .pluralsight-title {
-      font-size: 1.5em;
-    }
-
-    p {
-      line-height: 1.5em;
-    }
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Further Reading
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    There's a lot of great content out there to learn more about Mongoose.
-    This page has a list of video courses, books, and blog posts curated by
-    Mongoose maintainers. We've gone through every course, book, and article
-    on this page to make sure it is high quality.
-
-    * [Video Courses](#video-courses)
-    * [Books](#books)
-    * [Blog Posts](#blog-posts)
-
-    ## Video Courses
-
-    <a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-      <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-    </a>
-    <img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-    
-    <a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fapi-design-nodejs-express-mongo%2Ftable-of-contents">
-      API Design in Node.js Featuring Express & Mongo
-    </a>
-
-    This course is a great introduction to building a RESTful API with [Express](http://expressjs.com/)
-    and Mongoose. The instructor is [Scott Moss](https://frontendmasters.com/teachers/scott-moss/),
-    a serial entrepreneur and former intructor at [Hack Reactor](https://www.hackreactor.com/), San Francisco's number one coding bootcamp.
-
-    <div style="clear: both"></div>
-    <br><br>
-
-    <a href="https://thinkster.io/tutorials/node-json-api" class="pluralsight-link" style="padding:20px">
-      <img src="https://pbs.twimg.com/profile_images/819400302864412676/6x2g2XtJ_400x400.jpg" border="0" alt="" style="width: 140px" />
-    </a>
-  
-    <a class="pluralsight-title" href="https://thinkster.io/tutorials/node-json-api">
-      Building a Production Ready Node.js JSON API
-    </a>
-
-    <br><br>
-
-    [Thinkster](https://thinkster.io/) has created a full stack web
-    development course for just about every backend and frontend framework
-    you can think of. Want to learn how to build a full stack app with Vue
-    and Django, or with Angular and Rails? Thinkster has a course for that.
-    The Node.js tutorial walks you through building a production-ready
-    RESTful API with Express and Mongoose from scratch.
-
-    <div style="clear: both"></div>
-    <br><br>
-
-    <a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-      <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-    </a>
-    <img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-    <a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoose-for-nodejs-mongodb%2Ftable-of-contents">
-      Introduction to Mongoose for Node.js and MongoDB
-    </a>
-
-    <br><br>
-
-    Know someone who wants to get started building Node.js apps but doesn't have
-    a lot of software development experience?
-    This course is more beginner-friendly than _API Design_ and is a great
-    resource for beginners looking to get started.
-
-    <div style="clear: both"></div>
-    <br><br>
-
-    <a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-      <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-    </a>
-    <img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-    <a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">
-      RESTful Web Services with Node.js and Express
-    </a>
-
-    <br><br>
-
-    Looking for a course to take you from zero to Express + Mongoose
-    REST API fast? This is the one. This course is halfway
-    between _API Design_ and _Introduction to Mongoose_. It focuses more on
-    [Express](http://expressjs.com/), but also doesn't go into as much detail as _API Design_. 
-
-    <div style="clear: both"></div>
-    <br><br>
-
-    <a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-      <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-    </a>
-    <img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-    <a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fbuilding-business-applications-vuejs%2Ftable-of-contents">
-      Building Business Applications with Vue.js and MongoDB
-    </a>
-
-    <br><br>
-
-    This course walks you through building a full-stack web application using
-    the [VENoM Stack](https://medium.com/@audretschjames/venom-stack-docker-setup-for-local-development-457093761ad1).
-    Try this course if you're a [Vue.js](https://vuejs.org/) expert looking to
-    expand into backend engineering or an experienced MongoDB dev looking to
-    learn about frontend dev.
-
-    <div style="clear: both"></div>
-    <br><br>
-
-    <a href="//pluralsight.pxf.io/c/1321469/432943/7490" class="pluralsight-link">
-      <img src="//a.impactradius-go.com/display-ad/7490-432943" border="0" alt="" width="180" height="95"/>
-    </a>
-    <img height="0" width="0" src="//pluralsight.pxf.io/i/1321469/432943/7490" style="position:absolute;visibility:hidden;" border="0" />
-
-    <a class="pluralsight-title" href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fmongoosejs-moving-forward%2Ftable-of-contents">
-      Moving Forward with Mongoose.js
-    </a>
-
-    <br><br>
-
-    Stuck maintaining a legacy codebase on Mongoose 3.x? This course will
-    give you a detailed overview of the [breaking changes and new features in Mongoose 4.x](https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes),
-    so you can upgrade with confidence.
-
-    <div style="clear: both"></div>
-
-    ## Books
-
-    <a class="pluralsight-link" href="http://bit.ly/mongoose-book-2013">
-      <img src="https://s3.amazonaws.com/codebarbarian-images/mongoose.jpg" style="width: 180px">
-    </a>
-
-    <a class="pluralsight-title" href="http://bit.ly/mongoose-book-2013">
-      <i>Mongoose for Application Development</i> by Simon Holmes
-    </a>
-
-    This is the book on Mongoose. Even though it is from 2013,
-    _Mongoose for Application Development_ has stood the test of time. This
-    book does an excellent job summarizing the core ideas that make Mongoose so
-    powerful. Just sub out callbacks for promises.
-
-    <div style="clear: both"></div>
-
-    <a class="pluralsight-link" href="https://bit.ly/mongodb-schema-design">
-      <img src="https://s3.amazonaws.com/codebarbarian-images/schemadesign.jpg" style="width: 180px">
-    </a>
-
-    <a class="pluralsight-title" href="https://bit.ly/mongodb-schema-design">
-      <i>The Little MongoDB Schema Design Book</i> by Christian Kvalheim
-    </a>
-
-    Christian Kvalheim originally wrote the MongoDB Node.js driver in early 2010,
-    and maintained the driver almost singlehandedly until 2017. As maintainer
-    of the Node.js driver, Christian saw more Node.js+MongoDB code bases than
-    anyone, and his experience is unmatched.
-    This book distills 6 years of hard-learned lessons into concrete examples
-    of how to design MongoDB schemas for massive scale. If you want to learn
-    how to structure MongoDB schemas for an ecommerce store, a category tree, or a
-    blog that can support hundreds of millions of requests per day, this is
-    the book for you.
-
-    <div style="clear: both"></div>
-
-    ## Blog Posts
-
-    <a class="pluralsight-link" style="padding: 20px" href="https://medium.freecodecamp.org/introduction-to-mongoose-for-mongodb-d2a7aa593c57">
-      <img src="https://cdn-images-1.medium.com/max/800/1*uTZXsVta4TwghNobMkZeZg.png" style="width: 140px">
-    </a>
-
-    <a class="pluralsight-title" href="https://medium.freecodecamp.org/introduction-to-mongoose-for-mongodb-d2a7aa593c57">
-      <i>Introduction to Mongoose for MongoDB</i> on freeCodeCamp
-    </a>
-
-    Coming from an SQL background and having trouble understanding Mongoose and MongoDB?
-    This article explains the core concepts of Mongoose with references to similar
-    concepts in SQL.
-
-    <div style="clear: both"></div>
-
-    <a class="pluralsight-link" style="padding: 20px" href="https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/mongoose">
-      <img src="https://developer.mozilla.org/static/img/opengraph-logo.72382e605ce3.png" style="width: 140px">
-    </a>
-
-    <a class="pluralsight-title" href="https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/mongoose">
-      <i>Express Tutorial Part 3: Using a Database (with Mongoose)</i> on Mozilla Developer Network
-    </a>
-
-    Virtually every JavaScript developer has read MDN docs. They're usually one
-    of the top 3 results when you Google "javascript startswith" or any other
-    core JavaScript function. This tutorial provides an overview of Mongoose
-    in MDN's standard style and tone.
-
-    <div style="clear: both"></div>
\ No newline at end of file
diff --git a/docs/geojson.md b/docs/geojson.md
new file mode 100644
index 00000000000..ac2a726cb7f
--- /dev/null
+++ b/docs/geojson.md
@@ -0,0 +1,160 @@
+# Using GeoJSON
+
+<script>
+  _native.init("CK7DT53U",{
+    targetClass: 'native-inline'
+  });
+</script>
+
+<div class="native-inline">
+  <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
+</div>
+
+[GeoJSON](http://geojson.org/) is a format for storing geographic points and
+polygons. [MongoDB has excellent support for geospatial queries](http://thecodebarbarian.com/80-20-guide-to-mongodb-geospatial-queries)
+on GeoJSON objects. Let's take a look at how you can use Mongoose to store
+and query GeoJSON objects.
+
+<h2 id="points">Point Schema</h2>
+
+The most simple structure in GeoJSON is a point. Below is an example point
+representing the approximate location of [San Francisco](https://www.google.com/maps/@37.7,-122.5,9z).
+Note that longitude comes first in a GeoJSON coordinate array, **not** latitude.
+
+```
+{
+  "type" : "Point",
+  "coordinates" : [
+    -122.5,
+    37.7
+  ]
+}
+```
+
+Below is an example of a Mongoose schema where `location` is a point.
+
+```javascript
+const citySchema = new mongoose.Schema({
+  name: String,
+  location: {
+    type: {
+      type: String, // Don't do `{ location: { type: String } }`
+      enum: ['Point'], // 'location.type' must be 'Point'
+      required: true
+    },
+    coordinates: {
+      type: [Number],
+      required: true
+    }
+  }
+});
+```
+
+Using [subdocuments](/docs/subdocs.html), you can define a common `pointSchema` and reuse it everywhere you want to store a GeoJSON point.
+
+```javascript
+const pointSchema = new mongoose.Schema({
+  type: {
+    type: String,
+    enum: ['Point'],
+    required: true
+  },
+  coordinates: {
+    type: [Number],
+    required: true
+  }
+});
+
+const citySchema = new mongoose.Schema({
+  name: String,
+  location: {
+    type: pointSchema,
+    required: true
+  }
+});
+```
+
+<h2 id="polygons">Polygon Schema</h2>
+
+GeoJSON polygons let you define an arbitrary shape on a map. For example,
+the below polygon is a GeoJSON rectangle that approximates the border
+of the state of Colorado.
+
+```
+{
+  "type": "Polygon",
+  "coordinates": [[
+    [-109, 41],
+    [-102, 41],
+    [-102, 37],
+    [-109, 37],
+    [-109, 41]
+  ]]
+}
+```
+
+Polygons are tricky because they use triple nested arrays. Below is
+how you create a Mongoose schema where `coordinates` is a triple nested
+array of numbers.
+
+```javascript
+const polygonSchema = new mongoose.Schema({
+  type: {
+    type: String,
+    enum: ['Polygon'],
+    required: true
+  },
+  coordinates: {
+    type: [[[Number]]], // Array of arrays of arrays of numbers
+    required: true
+  }
+});
+
+const citySchema = new mongoose.Schema({
+  name: String,
+  location: polygonSchema
+});
+```
+
+<h2 id="querying">Geospatial Queries with Mongoose</h2>
+
+Mongoose queries support the same [geospatial query operators](http://thecodebarbarian.com/80-20-guide-to-mongodb-geospatial-queries)
+that the MongoDB driver does. For example, the below script saves a
+`city` document those `location` property is a GeoJSON point representing
+the city of Denver, Colorado. It then queries for all documents within
+a polygon representing the state of Colorado using
+[the MongoDB `$geoWithin` operator](https://docs.mongodb.com/manual/reference/operator/query/geoWithin/).
+
+<img src="https://i.imgur.com/i32pWnC.png">
+
+```javascript
+[require:geojson.*driver query]
+```
+
+Mongoose also has a [`within()` helper](/docs/api.html#query_Query-within)
+that's a shorthand for `$geoWithin`.
+
+```javascript
+[require:geojson.*within helper]
+```
+
+<h2 id="geospatial-indexes">Geospatial Indexes</h2>
+
+MongoDB supports [2dsphere indexes](https://docs.mongodb.com/manual/core/2dsphere/)
+for speeding up geospatial queries. Here's how you can define
+a 2dsphere index on a GeoJSON point:
+
+```javascript
+[require:geojson.*index$]
+```
+
+You can also define a geospatial index using the [`Schema#index()` function](/docs/api/schema.html#schema_Schema-index)
+as shown below.
+
+```javascript
+citySchema.index({ location: '2dsphere' });
+```
+
+MongoDB's [`$near` query operator](https://docs.mongodb.com/v4.0/reference/operator/query/near/#op._S_near)
+and [`$geoNear` aggregation stage](https://docs.mongodb.com/manual/reference/operator/aggregation/geoNear/#pipe._S_geoNear)
+_require_ a 2dsphere index. 
\ No newline at end of file
diff --git a/docs/geojson.pug b/docs/geojson.pug
deleted file mode 100644
index 0873c3f41e0..00000000000
--- a/docs/geojson.pug
+++ /dev/null
@@ -1,172 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    # Using GeoJSON
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    [GeoJSON](http://geojson.org/) is a format for storing geographic points and
-    polygons. [MongoDB has excellent support for geospatial queries](http://thecodebarbarian.com/80-20-guide-to-mongodb-geospatial-queries)
-    on GeoJSON objects. Let's take a look at how you can use Mongoose to store
-    and query GeoJSON objects.
-
-    <h2 id="points">Point Schema</h2>
-
-    The most simple structure in GeoJSON is a point. Below is an example point
-    representing the approximate location of [San Francisco](https://www.google.com/maps/@37.7,-122.5,9z).
-    Note that longitude comes first in a GeoJSON coordinate array, **not** latitude.
-
-    ```
-    {
-      "type" : "Point",
-      "coordinates" : [
-        -122.5,
-        37.7
-      ]
-    }
-    ```
-
-    Below is an example of a Mongoose schema where `location` is a point.
-
-    ```javascript
-    const citySchema = new mongoose.Schema({
-      name: String,
-      location: {
-        type: {
-          type: String, // Don't do `{ location: { type: String } }`
-          enum: ['Point'], // 'location.type' must be 'Point'
-          required: true
-        },
-        coordinates: {
-          type: [Number],
-          required: true
-        }
-      }
-    });
-    ```
-
-    Using [subdocuments](/docs/subdocs.html), you can define a common `pointSchema` and reuse it everywhere you want to store a GeoJSON point.
-
-    ```javascript
-    const pointSchema = new mongoose.Schema({
-      type: {
-        type: String,
-        enum: ['Point'],
-        required: true
-      },
-      coordinates: {
-        type: [Number],
-        required: true
-      }
-    });
-
-    const citySchema = new mongoose.Schema({
-      name: String,
-      location: {
-        type: pointSchema,
-        required: true
-      }
-    });
-    ```
-
-    <h2 id="polygons">Polygon Schema</h2>
-
-    GeoJSON polygons let you define an arbitrary shape on a map. For example,
-    the below polygon is a GeoJSON rectangle that approximates the border
-    of the state of Colorado.
-
-    ```
-    {
-      "type": "Polygon",
-      "coordinates": [[
-        [-109, 41],
-        [-102, 41],
-        [-102, 37],
-        [-109, 37],
-        [-109, 41]
-      ]]
-    }
-    ```
-
-    Polygons are tricky because they use triple nested arrays. Below is
-    how you create a Mongoose schema where `coordinates` is a triple nested
-    array of numbers.
-
-    ```javascript
-    const polygonSchema = new mongoose.Schema({
-      type: {
-        type: String,
-        enum: ['Polygon'],
-        required: true
-      },
-      coordinates: {
-        type: [[[Number]]], // Array of arrays of arrays of numbers
-        required: true
-      }
-    });
-
-    const citySchema = new mongoose.Schema({
-      name: String,
-      location: polygonSchema
-    });
-    ```
-
-    <h2 id="querying">Geospatial Queries with Mongoose</h2>
-
-    Mongoose queries support the same [geospatial query operators](http://thecodebarbarian.com/80-20-guide-to-mongodb-geospatial-queries)
-    that the MongoDB driver does. For example, the below script saves a
-    `city` document those `location` property is a GeoJSON point representing
-    the city of Denver, Colorado. It then queries for all documents within
-    a polygon representing the state of Colorado using
-    [the MongoDB `$geoWithin` operator](https://docs.mongodb.com/manual/reference/operator/query/geoWithin/).
-
-    <img src="https://i.imgur.com/i32pWnC.png">
-
-    ```javascript
-    [require:geojson.*driver query]
-    ```
-
-    Mongoose also has a [`within()` helper](/docs/api.html#query_Query-within)
-    that's a shorthand for `$geoWithin`.
-
-    ```javascript
-    [require:geojson.*within helper]
-    ```
-
-    <h2 id="geospatial-indexes">Geospatial Indexes</h2>
-
-    MongoDB supports [2dsphere indexes](https://docs.mongodb.com/manual/core/2dsphere/)
-    for speeding up geospatial queries. Here's how you can define
-    a 2dsphere index on a GeoJSON point:
-
-    ```javascript
-    [require:geojson.*index$]
-    ```
-
-    You can also define a geospatial index using the [`Schema#index()` function](/docs/api/schema.html#schema_Schema-index)
-    as shown below.
-
-    ```javascript
-    citySchema.index({ location: '2dsphere' });
-    ```
-
-    MongoDB's [`$near` query operator](https://docs.mongodb.com/v4.0/reference/operator/query/near/#op._S_near)
-    and [`$geoNear` aggregation stage](https://docs.mongodb.com/manual/reference/operator/aggregation/geoNear/#pipe._S_geoNear)
-    _require_ a 2dsphere index. 
diff --git a/docs/jest.md b/docs/jest.md
new file mode 100644
index 00000000000..55e317e3611
--- /dev/null
+++ b/docs/jest.md
@@ -0,0 +1,82 @@
+# Testing Mongoose with [Jest](https://www.npmjs.com/package/jest)
+
+Jest is a client-side JavaScript testing library developed by Facebook.
+Because Jest is designed primarily for testing React applications, using it to test Node.js server-side applications comes with a lot of caveats.
+We strongly advise against using Jest for testing any Node.js apps unless you are an expert developer with an intimate knowledge of Jest.
+
+If you choose to delve into dangerous waters and test Mongoose apps with Jest, here's what you need to know:
+
+<h2 id="recommended-testenvironment"><a href="#recommended-testenvironment">Recommended <code>testEnvironment</code></a></h2>
+
+Do **not** use Jest's default [`jsdom` test environment](https://jestjs.io/docs/en/configuration.html#testenvironment-string)
+when testing Mongoose apps, _unless_ you are explicitly testing an
+application that only uses
+[Mongoose's browser library](https://mongoosejs.com/docs/browser.html).
+
+The `jsdom` test environment attempts to create a browser-like test
+environment in Node.js, and it comes with numerous nasty surprises like a
+[stubbed `setTimeout()` function](https://github.com/jsdom/jsdom/commit/3f306bea5362aceb2a219a2e98ff96a7464d2f19#commitcomment-31316213)
+that silently fails after tests are finished. Mongoose does not support jsdom
+in general and is not expected to function correctly in the `jsdom` test
+environment.
+
+To change your `testEnvironment` to Node.js, add `testEnvironment` to your
+`jest.config.js` file:
+
+```javascript
+module.exports = {
+  testEnvironment: 'node'
+};
+```
+
+<h2 id="timer-mocks"><a href="#timer-mocks">Timer Mocks</a></h2>
+
+Absolutely do **not** use [timer mocks](https://jestjs.io/docs/en/timer-mocks.html)
+when testing Mongoose apps. Fake timers stub out global functions like
+`setTimeout()` and `setInterval()`, which causes problems when an underlying
+library uses these functions. The MongoDB Node.js driver uses these functions
+for deferring work until the next tick of the event loop and for monitoring
+connections to the MongoDB server.
+    
+Mongoose devs have already refactored out code
+to [avoid using `setImmediate()`](https://github.com/Automattic/mongoose/issues/6074)
+to defer work to the next tick of the event loop, but we can't reasonably
+ensure that every library Mongoose depends on doesn't use `setImmediate()`.
+
+Mongoose uses `nextTick()`, which [Jest's underlying dependency explicitly doesn't stub by default](https://sinonjs.org/releases/latest/fake-timers/).
+But, `process.nextTick()` isn't the same as `setImmediate()` because of
+[microtasks vs macrotasks](https://abc.danch.me/microtasks-macrotasks-more-on-the-event-loop-881557d7af6f#2261),
+so underlying libraries like the [MongoDB driver](http://npmjs.com/package/mongodb) may use `setImmediate()`.
+
+To work around this, create your own wrapper around `setTimeout()` and
+stub that instead using [sinon](http://npmjs.com/package/sinon).
+
+```javascript
+// time.js
+exports.setTimeout = function() {
+  return global.setTimeout.apply(global, arguments);
+};
+
+// Tests
+const time = require('../util/time');
+const sinon = require('sinon');
+sinon.stub(time, 'setTimeout');
+```
+
+<h2 id="globalsetup-and-globalteardown"><a href="#globalsetup-and-globalteardown"><code>globalSetup</code> and <code>globalTeardown</code></a></h2>
+
+Do **not** use `globalSetup` to call `mongoose.connect()` or
+`mongoose.createConnection()`. Jest runs `globalSetup` in
+a [separate environment](https://github.com/facebook/jest/issues/7184),
+so you cannot use any connections you create in `globalSetup`
+in your tests.
+
+## Further Reading
+
+Want to learn more about testing Mongoose apps? The
+[RESTful Web Services with Node.js and Express](https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents)
+course on Pluralsight has a great section on testing Mongoose apps with [Mocha](http://npmjs.com/package/mocha).
+
+<a href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">
+  <img src="https://i.imgur.com/KouuaAZ.png">
+</a>
\ No newline at end of file
diff --git a/docs/jest.pug b/docs/jest.pug
deleted file mode 100644
index 2b54cecb8d8..00000000000
--- a/docs/jest.pug
+++ /dev/null
@@ -1,107 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet" href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    # Testing Mongoose with [Jest](https://www.npmjs.com/package/jest)
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Jest is a client-side JavaScript testing library developed by Facebook.
-    Because Jest is designed primarily for testing React applications, using
-    it to test Node.js server-side applications comes with a lot of caveats.
-    We strongly advise against using Jest for testing any Node.js apps unless
-    you are an expert developer with an intimate knowledge of Jest.
-
-    If you choose to delve into dangerous waters and test Mongoose apps with
-    Jest, here's what you need to know:
-
-    <h2 id="recommended-testenvironment"><a href="#recommended-testenvironment">Recommended <code>testEnvironment</code></a></h2>
-
-    Do **not** use Jest's default [`jsdom` test environment](https://jestjs.io/docs/en/configuration.html#testenvironment-string)
-    when testing Mongoose apps, _unless_ you are explicitly testing an
-    application that only uses
-    [Mongoose's browser library](https://mongoosejs.com/docs/browser.html).
-
-    The `jsdom` test environment attempts to create a browser-like test
-    environment in Node.js, and it comes with numerous nasty surprises like a
-    [stubbed `setTimeout()` function](https://github.com/jsdom/jsdom/commit/3f306bea5362aceb2a219a2e98ff96a7464d2f19#commitcomment-31316213)
-    that silently fails after tests are finished. Mongoose does not support jsdom
-    in general and is not expected to function correctly in the `jsdom` test
-    environment.
-
-    To change your `testEnvironment` to Node.js, add `testEnvironment` to your
-    `jest.config.js` file:
-
-    ```javascript
-    module.exports = {
-      testEnvironment: 'node'
-    };
-    ```
-
-    <h2 id="timer-mocks"><a href="#timer-mocks">Timer Mocks</a></h2>
-
-    Absolutely do **not** use [timer mocks](https://jestjs.io/docs/en/timer-mocks.html)
-    when testing Mongoose apps. Fake timers stub out global functions like
-    `setTimeout()` and `setInterval()`, which causes problems when an underlying
-    library uses these functions. The MongoDB Node.js driver uses these functions
-    for deferring work until the next tick of the event loop and for monitoring
-    connections to the MongoDB server.
-    
-    Mongoose devs have already refactored out code
-    to [avoid using `setImmediate()`](https://github.com/Automattic/mongoose/issues/6074)
-    to defer work to the next tick of the event loop, but we can't reasonably
-    ensure that every library Mongoose depends on doesn't use `setImmediate()`.
-
-    Mongoose uses `nextTick()`, which [Jest's underlying dependency explicitly doesn't stub by default](https://sinonjs.org/releases/latest/fake-timers/).
-    But, `process.nextTick()` isn't the same as `setImmediate()` because of
-    [microtasks vs macrotasks](https://abc.danch.me/microtasks-macrotasks-more-on-the-event-loop-881557d7af6f#2261),
-    so underlying libraries like the [MongoDB driver](http://npmjs.com/package/mongodb) may use `setImmediate()`.
-
-    To work around this, create your own wrapper around `setTimeout()` and
-    stub that instead using [sinon](http://npmjs.com/package/sinon).
-
-    ```javascript
-    // time.js
-    exports.setTimeout = function() {
-      return global.setTimeout.apply(global, arguments);
-    };
-
-    // Tests
-    const time = require('../util/time');
-    const sinon = require('sinon');
-    sinon.stub(time, 'setTimeout');
-    ```
-
-    <h2 id="globalsetup-and-globalteardown"><a href="#globalsetup-and-globalteardown"><code>globalSetup</code> and <code>globalTeardown</code></a></h2>
-
-    Do **not** use `globalSetup` to call `mongoose.connect()` or
-    `mongoose.createConnection()`. Jest runs `globalSetup` in
-    a [separate environment](https://github.com/facebook/jest/issues/7184),
-    so you cannot use any connections you create in `globalSetup`
-    in your tests.
-
-    ## Further Reading
-
-    Want to learn more about testing Mongoose apps? The
-    [RESTful Web Services with Node.js and Express](https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents)
-    course on Pluralsight has a great section on testing Mongoose apps with [Mocha](http://npmjs.com/package/mocha).
-
-    <a href="https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents">
-      <img src="https://i.imgur.com/KouuaAZ.png">
-    </a>
diff --git a/docs/lambda.md b/docs/lambda.md
new file mode 100644
index 00000000000..c03c16fc743
--- /dev/null
+++ b/docs/lambda.md
@@ -0,0 +1,85 @@
+# Using Mongoose With AWS Lambda
+
+[AWS Lambda](https://aws.amazon.com/lambda/) is a popular service for running
+arbitrary functions without managing individual servers. Using Mongoose in your
+AWS Lambda functions is easy. Here's a sample function that connects to a
+MongoDB instance and finds a single document:
+
+```javascript
+const mongoose = require('mongoose');
+
+let conn = null;
+
+const uri = 'YOUR CONNECTION STRING HERE';
+
+exports.handler = async function(event, context) {
+  // Make sure to add this so you can re-use `conn` between function calls.
+  // See https://www.mongodb.com/blog/post/serverless-development-with-nodejs-aws-lambda-mongodb-atlas
+  context.callbackWaitsForEmptyEventLoop = false;
+
+  // Because `conn` is in the global scope, Lambda may retain it between
+  // function calls thanks to `callbackWaitsForEmptyEventLoop`.
+  // This means your Lambda function doesn't have to go through the
+  // potentially expensive process of connecting to MongoDB every time.
+  if (conn == null) {
+    conn = mongoose.createConnection(uri, {
+      // Buffering means mongoose will queue up operations if it gets
+      // disconnected from MongoDB and send them when it reconnects.
+      // With serverless, better to fail fast if not connected.
+      bufferCommands: false, // Disable mongoose buffering
+      bufferMaxEntries: 0 // and MongoDB driver buffering
+    });
+    
+    // `await`ing connection after assigning to the `conn` variable
+    // to avoid multiple function calls creating new connections
+    await conn;
+    conn.model('Test', new mongoose.Schema({ name: String }));
+  }
+
+  const M = conn.model('Test');
+
+  const doc = await M.findOne();
+  console.log(doc);
+
+  return doc;
+};
+```
+
+To import this function into Lambda, go [the AWS Lambda console](https://console.aws.amazon.com/lambda)
+and click "Create Function".
+
+<a href="https://i.imgur.com/FlAD0vT.png"><img src="https://i.imgur.com/FlAD0vT.png"></a>
+
+Create a function called "mongoose-test" with the below settings:
+
+<a href="https://i.imgur.com/YOYJzeO.png"><img src="https://i.imgur.com/YOYJzeO.png"></a>
+
+Copy the source code into a file called `lambda.js`. Then run `npm install mongoose co`.
+Finally, run `zip -r mongoose-test.zip node_modules/ lambda.js` to create a
+zip that you can upload to Lambda using the "Upload a Zip File" option under "Function code".
+Make sure you also change the "Handler" input to `lambda.handler` to match the `lambda.js` file's `handler` function.
+
+<a href="https://i.imgur.com/BXc9egq.png"><img src="https://i.imgur.com/BXc9egq.png"></a>
+
+Next, click the "Save" button and then the "Test" button. The "Test" button will
+ask you to create a new test event, just create one because your inputs don't matter
+for this example. Then, hit "Test" again to actually run your function:
+
+<a href="https://i.imgur.com/2UKtWYq.png"><img src="https://i.imgur.com/2UKtWYq.png"></a>
+
+If your MongoDB database goes down in between function calls, you may
+see the below error message:
+
+```
+cannot find account after reload: could not find config for <hostname>
+```
+
+Lambda's JavaScript framework recently added support for
+async/await as long as you're using Node 8.x, so make sure you're not
+using Node.js 6.x.
+
+*Want to learn how to check whether your favorite JavaScript frameworks, like [Express](http://expressjs.com/) or [React](https://reactjs.org/), work with async/await? Spoiler alert: neither Express nor React support async/await. Chapter 4 of Mastering Async/Await explains the basic principles for determining whether a framework supports async/await. [Get your copy!](http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=lambda)*
+
+<a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=lambda" style="margin-left: 100px">
+  <img src="/docs/images/asyncawait.png" style="width: 650px" />
+</a>
diff --git a/docs/lambda.pug b/docs/lambda.pug
deleted file mode 100644
index 1b5b952058a..00000000000
--- a/docs/lambda.pug
+++ /dev/null
@@ -1,106 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet" href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  h2 Using Mongoose With AWS Lambda
-  :markdown
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    [AWS Lambda](https://aws.amazon.com/lambda/) is a popular service for running
-    arbitrary functions without managing individual servers. Using Mongoose in your
-    AWS Lambda functions is easy. Here's a sample function that connects to a
-    MongoDB instance and finds a single document:
-
-    ```javascript
-    const mongoose = require('mongoose');
-
-    let conn = null;
-
-    const uri = 'YOUR CONNECTION STRING HERE';
-
-    exports.handler = async function(event, context) {
-      // Make sure to add this so you can re-use `conn` between function calls.
-      // See https://www.mongodb.com/blog/post/serverless-development-with-nodejs-aws-lambda-mongodb-atlas
-      context.callbackWaitsForEmptyEventLoop = false;
-
-      // Because `conn` is in the global scope, Lambda may retain it between
-      // function calls thanks to `callbackWaitsForEmptyEventLoop`.
-      // This means your Lambda function doesn't have to go through the
-      // potentially expensive process of connecting to MongoDB every time.
-      if (conn == null) {
-        conn = mongoose.createConnection(uri, {
-          // Buffering means mongoose will queue up operations if it gets
-          // disconnected from MongoDB and send them when it reconnects.
-          // With serverless, better to fail fast if not connected.
-          bufferCommands: false, // Disable mongoose buffering
-          bufferMaxEntries: 0 // and MongoDB driver buffering
-        });
-        
-        // `await`ing connection after assigning to the `conn` variable
-        // to avoid multiple function calls creating new connections
-        await conn;
-        conn.model('Test', new mongoose.Schema({ name: String }));
-      }
-
-      const M = conn.model('Test');
-
-      const doc = await M.findOne();
-      console.log(doc);
-
-      return doc;
-    };
-    ```
-
-    To import this function into Lambda, go [the AWS Lambda console](https://console.aws.amazon.com/lambda)
-    and click "Create Function".
-
-    <a href="https://i.imgur.com/FlAD0vT.png"><img src="https://i.imgur.com/FlAD0vT.png"></a>
-
-    Create a function called "mongoose-test" with the below settings:
-
-    <a href="https://i.imgur.com/YOYJzeO.png"><img src="https://i.imgur.com/YOYJzeO.png"></a>
-
-    Copy the source code into a file called `lambda.js`. Then run `npm install mongoose co`.
-    Finally, run `zip -r mongoose-test.zip node_modules/ lambda.js` to create a
-    zip that you can upload to Lambda using the "Upload a Zip File" option under "Function code".
-    Make sure you also change the "Handler" input to `lambda.handler` to match the `lambda.js` file's `handler` function.
-
-    <a href="https://i.imgur.com/BXc9egq.png"><img src="https://i.imgur.com/BXc9egq.png"></a>
-
-    Next, click the "Save" button and then the "Test" button. The "Test" button will
-    ask you to create a new test event, just create one because your inputs don't matter
-    for this example. Then, hit "Test" again to actually run your function:
-
-    <a href="https://i.imgur.com/2UKtWYq.png"><img src="https://i.imgur.com/2UKtWYq.png"></a>
-
-    If your MongoDB database goes down in between function calls, you may
-    see the below error message:
-
-    ```
-    cannot find account after reload: could not find config for <hostname>
-    ```
-
-    Lambda's JavaScript framework recently added support for
-    async/await as long as you're using Node 8.x, so make sure you're not
-    using Node.js 6.x.
-
-    *Want to learn how to check whether your favorite JavaScript frameworks, like [Express](http://expressjs.com/) or [React](https://reactjs.org/), work with async/await? Spoiler alert: neither Express nor React support async/await. Chapter 4 of Mastering Async/Await explains the basic principles for determining whether a framework supports async/await. [Get your copy!](http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=lambda)*
-
-    <a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=lambda" style="margin-left: 100px">
-      <img src="/docs/images/asyncawait.png" style="width: 650px" />
-    </a>
diff --git a/docs/migrating_to_5.md b/docs/migrating_to_5.md
new file mode 100644
index 00000000000..53048ab69e9
--- /dev/null
+++ b/docs/migrating_to_5.md
@@ -0,0 +1,548 @@
+## Migrating from 4.x to 5.x
+
+There are several [backwards-breaking changes](https://github.com/Automattic/mongoose/blob/master/History.md)
+you should be aware of when migrating from Mongoose 4.x to Mongoose 5.x.
+
+If you're still on Mongoose 3.x, please read the [Mongoose 3.x to 4.x migration guide](migration.html).
+
+* [Version Requirements](#version-requirements)
+* [Query Middleware](#query-middleware)
+* [Promises and Callbacks for `mongoose.connect()`](#promises-and-callbacks)
+* [Connection Logic and `useMongoClient`](#connection-logic)
+* [Setter Order](#setter-order)
+* [Checking if a path is populated](#id-getter)
+* [Return Values for `remove()` and `deleteX()`](#return-value-for-delete)
+* [Aggregation Cursors](#aggregation-cursors)
+* [geoNear](#geonear)
+* [Required URI encoding of connection strings](#uri-encoding)
+* [Passwords which contain certain characters](#password-characters)
+* [Domain sockets](#domain-sockets)
+* [`toObject()` Options](#toobject-options)
+* [Aggregate Parameters](#aggregate-parameters)
+* [Boolean Casting](#boolean-casting)
+* [Query Casting](#query-casting)
+* [Post Save Hooks Get Flow Control](#post-save-flow-control)
+* [The `$pushAll` Operator](#pushall)
+* [Always Use Forward Key Order](#retain-key-order)
+* [Run setters on queries](#run-setters-on-queries)
+* [Pre-compiled Browser Bundle](#browser-bundle)
+* [Save Errors](#save-errors)
+* [Init hook signatures](#init-hooks)
+* [`numAffected` and `save()`](#save-num-affected)
+* [`remove()` and debouncing](#remove-debounce)
+* [`getPromiseConstructor()`](#get-promise-constructor)
+* [Passing Parameters from Pre Hooks](#pre-hook-params)
+* [`required` validator for arrays](#array-required)
+* [debug output defaults to stdout instead of stderr](#debug-output)
+* [Overwriting filter properties](#overwrite-filter)
+* [`bulkWrite()` results](#bulkwrite-results)
+* [Strict SSL validation](#strict-ssl-validation)
+
+<h3 id="version-requirements"><a href="#version-requirements">Version Requirements</a></h3>
+
+Mongoose now requires Node.js >= 4.0.0 and MongoDB >= 3.0.0.
+[MongoDB 2.6](https://www.mongodb.com/blog/post/mongodb-2-6-end-of-life) and
+[Node.js < 4](https://github.com/nodejs/Release) where both EOL-ed in 2016.
+
+<h3 id="query-middleware"><a href="#query-middleware">Query Middleware</a></h3>
+
+Query middleware is now compiled when you call `mongoose.model()` or `db.model()`. If you add query middleware after calling `mongoose.model()`, that middleware will **not** get called.
+
+```javascript
+const schema = new Schema({ name: String });
+const MyModel = mongoose.model('Test', schema);
+schema.pre('find', () => { console.log('find!'); });
+
+MyModel.find().exec(function() {
+  // In mongoose 4.x, the above `.find()` will print "find!"
+  // In mongoose 5.x, "find!" will **not** be printed.
+  // Call `pre('find')` **before** calling `mongoose.model()` to make the middleware apply.
+});
+```
+
+<h3 id="promises-and-callbacks"><a href="#promises-and-callbacks">
+  Promises and Callbacks for `mongoose.connect()`
+</a></h3>
+
+`mongoose.connect()` and `mongoose.disconnect()` now return a promise if no callback specified, or `null` otherwise. It does **not** return the mongoose singleton.
+
+```javascript
+// Worked in mongoose 4. Does **not** work in mongoose 5, `mongoose.connect()`
+// now returns a promise consistently. This is to avoid the horrible things
+// we've done to allow mongoose to be a thenable that resolves to itself.
+mongoose.connect('mongodb://localhost:27017/test').model('Test', new Schema({}));
+
+// Do this instead
+mongoose.connect('mongodb://localhost:27017/test');
+mongoose.model('Test', new Schema({}));
+```
+
+<h3 id="connection-logic"><a href="#connection-logic">
+  Connection Logic and `useMongoClient`
+</a></h3>
+
+The [`useMongoClient` option](/docs/4.x/docs/connections.html#use-mongo-client) was
+removed in Mongoose 5, it is now always `true`. As a consequence, Mongoose 5
+no longer supports several function signatures for `mongoose.connect()` that
+worked in Mongoose 4.x if the `useMongoClient` option was off. Below are some
+examples of `mongoose.connect()` calls that do **not** work in Mongoose 5.x.
+
+* `mongoose.connect('localhost', 27017);`
+* `mongoose.connect('localhost', 'mydb', 27017);`
+* `mongoose.connect('mongodb://host1:27017,mongodb://host2:27017');`
+
+In Mongoose 5.x, the first parameter to `mongoose.connect()` and `mongoose.createConnection()`, if specified, **must** be a [MongoDB connection string](https://docs.mongodb.com/manual/reference/connection-string/). The
+connection string and options are then passed down to [the MongoDB Node.js driver's `MongoClient.connect()` function](http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#.connect). Mongoose does not modify the connection string, although `mongoose.connect()` and `mongoose.createConnection()` support a [few additional options in addition to the ones the MongoDB driver supports](http://mongoosejs.com/docs/connections.html#options).
+
+<h3 id="setter-order"><a href="#setter-order">
+  Setter Order
+</a></h3>
+
+Setters run in reverse order in 4.x:
+
+```javascript
+const schema = new Schema({ name: String });
+schema.path('name').
+  set(() => console.log('This will print 2nd')).
+  set(() => console.log('This will print first'));
+```
+
+In 5.x, setters run in the order they're declared.
+
+```javascript
+const schema = new Schema({ name: String });
+schema.path('name').
+  set(() => console.log('This will print first')).
+  set(() => console.log('This will print 2nd'));
+```
+
+<h3 id="id-getter"><a href="#id-getter">
+  Checking if a path is populated
+</a></h3>
+
+Mongoose 5.1.0 introduced an `_id` getter to ObjectIds that lets you get an ObjectId regardless of whether a path
+is populated.
+
+```javascript
+const blogPostSchema = new Schema({
+  title: String,
+  author: {
+    type: mongoose.Schema.Types.ObjectId,
+    ref: 'Author'
+  }
+});
+const BlogPost = mongoose.model('BlogPost', blogPostSchema);
+
+await BlogPost.create({ title: 'test', author: author._id });
+const blogPost = await BlogPost.findOne();
+
+console.log(blogPost.author); // '5b207f84e8061d1d2711b421'
+// New in Mongoose 5.1.0: this will print '5b207f84e8061d1d2711b421' as well
+console.log(blogPost.author._id);
+
+await blogPost.populate('author');
+console.log(blogPost.author._id); '5b207f84e8061d1d2711b421'
+```
+
+As a consequence, checking whether `blogPost.author._id` is [no longer viable as a way to check whether `author` is populated](https://github.com/Automattic/mongoose/issues/6415#issuecomment-388579185). Use `blogPost.populated('author') != null` or `blogPost.author instanceof mongoose.Types.ObjectId` to check whether `author` is populated instead.
+
+Note that you can call `mongoose.set('objectIdGetter', false)` to change this behavior.
+
+<h3 id="return-value-for-delete"><a href="#return-value-for-delete">
+  Return Values for `remove()` and `deleteX()`
+</a></h3>
+
+`deleteOne()`, `deleteMany()`, and `remove()` now resolve to the result object
+rather than the full [driver `WriteOpResult` object](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~writeOpCallback).
+
+```javascript
+// In 4.x, this is how you got the number of documents deleted
+MyModel.deleteMany().then(res => console.log(res.result.n));
+// In 5.x this is how you get the number of documents deleted
+MyModel.deleteMany().then(res => res.n);
+```
+
+<h3 id="aggregation-cursors"><a href="#aggregation-cursors">
+  Aggregation Cursors
+</a></h3>
+
+The `useMongooseAggCursor` option from 4.x is now always on. This is the new syntax for aggregation cursors in mongoose 5:
+
+```javascript
+// When you call `.cursor()`, `.exec()` will now return a mongoose aggregation
+// cursor.
+const cursor = MyModel.aggregate([{ $match: { name: 'Val' } }]).cursor().exec();
+// No need to `await` on the cursor or wait for a promise to resolve
+cursor.eachAsync(doc => console.log(doc));
+
+// Can also pass options to `cursor()`
+const cursorWithOptions = MyModel.
+  aggregate([{ $match: { name: 'Val' } }]).
+  cursor({ batchSize: 10 }).
+  exec();
+```
+
+<h3 id="geonear"><a href="#geonear">
+  geoNear
+</a></h3>
+
+`Model.geoNear()` has been removed because the [MongoDB driver no longer supports it](https://github.com/mongodb/node-mongodb-native/blob/master/CHANGES_3.0.0.md#geonear-command-helper)
+
+<h3 id="uri-encoding"><a href="#uri-encoding">
+  Required URI encoding of connection strings
+</a></h3>
+
+Due to changes in the MongoDB driver, connection strings must be URI encoded.
+
+If they are not, connections may fail with an illegal character message.
+
+<h3 id="password-characters"><a href="#password-characters">
+  Passwords which contain certain characters
+</a></h3>
+
+See a [full list of affected characters](https://developer.mozilla.org/en-US/docs/Glossary/percent-encoding).
+
+If your app is used by a lot of different connection strings, it's possible
+that your test cases will pass, but production passwords will fail. Encode all your connection
+strings to be safe.
+
+If you want to continue to use unencoded connection strings, the easiest fix is to use
+the `mongodb-uri` module to parse the connection strings, and then produce the properly encoded
+versions. You can use a function like this:
+
+```javascript
+const uriFormat = require('mongodb-uri')
+function encodeMongoURI (urlString) {
+    if (urlString) {
+      let parsed = uriFormat.parse(urlString)
+      urlString = uriFormat.format(parsed);
+    }
+    return urlString;
+  }
+}
+
+// Your un-encoded string.
+const mongodbConnectString = "mongodb://...";
+mongoose.connect(encodeMongoURI(mongodbConnectString))
+```
+
+The function above is safe to use whether the existing string is already encoded or not.
+
+<h3 id="domain-sockets"><a href="#domain-sockets">
+  Domain sockets
+</a></h3>
+
+Domain sockets must be URI encoded. For example:
+
+```javascript
+// Works in mongoose 4. Does **not** work in mongoose 5 because of more
+// stringent URI parsing.
+const host = '/tmp/mongodb-27017.sock';
+mongoose.createConnection(`mongodb://aaron:psw@${host}/fake`);
+
+// Do this instead
+const host = encodeURIComponent('/tmp/mongodb-27017.sock');
+mongoose.createConnection(`mongodb://aaron:psw@${host}/fake`);
+```
+
+<h3 id="toobject-options"><a href="#toobject-options">
+  `toObject()` Options
+</a></h3>
+
+The `options` parameter to `toObject()` and `toJSON()` merge defaults rather than overwriting them.
+
+```javascript
+// Note the `toObject` option below
+const schema = new Schema({ name: String }, { toObject: { virtuals: true } });
+schema.virtual('answer').get(() => 42);
+const MyModel = db.model('MyModel', schema);
+
+const doc = new MyModel({ name: 'test' });
+// In mongoose 4.x this prints "undefined", because `{ minimize: false }`
+// overwrites the entire schema-defined options object.
+// In mongoose 5.x this prints "42", because `{ minimize: false }` gets
+// merged with the schema-defined options.
+console.log(doc.toJSON({ minimize: false }).answer);
+```
+
+<h3 id="aggregate-parameters"><a href="#aggregate-parameters">
+  Aggregate Parameters
+</a></h3>
+
+`aggregate()` no longer accepts a spread, you **must** pass your aggregation pipeline as an array. The below code worked in 4.x:
+
+```javascript
+MyModel.aggregate({ $match: { isDeleted: false } }, { $skip: 10 }).exec(cb);
+```
+
+The above code does **not** work in 5.x, you **must** wrap the `$match` and `$skip` stages in an array.
+
+```javascript
+MyModel.aggregate([{ $match: { isDeleted: false } }, { $skip: 10 }]).exec(cb);
+```
+
+<h3 id="boolean-casting"><a href="#boolean-casting">
+  Boolean Casting
+</a></h3>
+
+By default, mongoose 4 would coerce any value to a boolean without error.
+
+```javascript
+// Fine in mongoose 4, would save a doc with `boolField = true`
+const MyModel = mongoose.model('Test', new Schema({
+  boolField: Boolean
+}));
+
+MyModel.create({ boolField: 'not a boolean' });
+```
+
+Mongoose 5 only casts the following values to `true`:
+
+* `true`
+* `'true'`
+* `1`
+* `'1'`
+* `'yes'`
+
+And the following values to `false`:
+
+* `false`
+* `'false'`
+* `0`
+* `'0'`
+* `'no'`
+
+All other values will cause a `CastError`
+
+<h3 id="query-casting"><a href="#query-casting">
+  Query Casting
+</a></h3>
+
+Casting for `update()`, `updateOne()`, `updateMany()`, `replaceOne()`,
+`remove()`, `deleteOne()`, and `deleteMany()` doesn't happen until `exec()`.
+This makes it easier for hooks and custom query helpers to modify data, because
+mongoose won't restructure the data you passed in until after your hooks and
+query helpers have ran. It also makes it possible to set the `overwrite` option
+_after_ passing in an update.
+
+```javascript
+// In mongoose 4.x, this becomes `{ $set: { name: 'Baz' } }` despite the `overwrite`
+// In mongoose 5.x, this overwrite is respected and the first document with
+// `name = 'Bar'` will be replaced with `{ name: 'Baz' }`
+User.where({ name: 'Bar' }).update({ name: 'Baz' }).setOptions({ overwrite: true });
+```
+
+<h3 id="post-save-flow-control"><a href="#post-save-flow-control">
+  Post Save Hooks Get Flow Control
+</a></h3>
+
+Post hooks now get flow control, which means async post save hooks and child document post save hooks execute **before** your `save()` callback.
+
+```javascript
+const ChildModelSchema = new mongoose.Schema({
+  text: {
+    type: String
+  }
+});
+ChildModelSchema.post('save', function(doc) {
+  // In mongoose 5.x this will print **before** the `console.log()`
+  // in the `save()` callback. In mongoose 4.x this was reversed.
+  console.log('Child post save');
+});
+const ParentModelSchema = new mongoose.Schema({
+  children: [ChildModelSchema]
+});
+
+const Model = mongoose.model('Parent', ParentModelSchema);
+const m = new Model({ children: [{ text: 'test' }] });
+m.save(function() {
+  // In mongoose 5.xm this prints **after** the "Child post save" message.
+  console.log('Save callback');
+});
+```
+
+<h3 id="pushall"><a href="#pushall">
+  The `$pushAll` Operator
+</a></h3>
+
+`$pushAll` is no longer supported and no longer used internally for `save()`, since it has been [deprecated since MongoDB 2.4](https://docs.mongodb.com/manual/reference/operator/update/pushAll/). Use `$push` with `$each` instead.
+
+<h3 id="retain-key-order"><a href="#retain-key-order">
+  Always Use Forward Key Order
+</a></h3>
+
+The `retainKeyOrder` option was removed, mongoose will now always retain the same key position when cloning objects. If you have queries or indexes that rely on reverse key order, you will have to change them.
+
+<h3 id="run-setters-on-queries"><a href="#run-setters-on-queries">
+  Run setters on queries
+</a></h3>
+
+Setters now run on queries by default, and the old `runSettersOnQuery` option
+has been removed.
+
+```javascript
+const schema = new Schema({
+  email: { type: String, lowercase: true }
+});
+const Model = mongoose.model('Test', schema);
+Model.find({ email: 'FOO@BAR.BAZ' }); // Converted to `find({ email: 'foo@bar.baz' })`
+```
+
+<h3 id="browser-bundle"><a href="#browser-bundle">
+  Pre-compiled Browser Bundle
+</a></h3>
+
+We no longer have a pre-compiled version of mongoose for the browser. If you want to use mongoose schemas in the browser, you need to build your own bundle with browserify/webpack.
+
+<h3 id="save-errors"><a href="#save-errors">
+  Save Errors
+</a></h3>
+
+The `saveErrorIfNotFound` option was removed, mongoose will now always error out from `save()` if the underlying document was not found
+
+<h3 id="init-hooks"><a href="#init-hooks">
+  Init hook signatures
+</a></h3>
+
+`init` hooks are now fully synchronous and do not receive `next()` as a parameter.
+
+`Document.prototype.init()` no longer takes a callback as a parameter. It
+was always synchronous, just had a callback for legacy reasons.
+
+<h3 id="save-num-affected"><a href="#save-num-affected">
+  `numAffected` and `save()`
+</a></h3>
+
+`doc.save()` no longer passes `numAffected` as a 3rd param to its callback.
+
+<h3 id="remove-debounce"><a href="#remove-debounce">
+  `remove()` and debouncing
+</a></h3>
+
+`doc.remove()` no longer debounces
+
+<h3 id="get-promise-constructor"><a href="#get-promise-constructor">
+  `getPromiseConstructor()`
+</a></h3>
+
+`getPromiseConstructor()` is gone, just use `mongoose.Promise`.
+
+<h3 id="pre-hook-params"><a href="#pre-hook-params">
+  Passing Parameters from Pre Hooks
+</a></h3>
+
+You cannot pass parameters to the next pre middleware in the chain using `next()` in mongoose 5.x. In mongoose 4, `next('Test')` in pre middleware would call the
+next middleware with 'Test' as a parameter. Mongoose 5.x has removed support for this.
+
+<h3 id="array-required"><a href="#array-required">
+  `required` validator for arrays
+</a></h3>
+
+In mongoose 5 the `required` validator only verifies if the value is an
+array. That is, it will **not** fail for _empty_ arrays as it would in
+mongoose 4.
+
+<h3 id="debug-output"><a href="#debug-output">
+  debug output defaults to stdout instead of stderr
+</a></h3>
+
+In mongoose 5 the default debug function uses `console.info()` to display messages instead of `console.error()`.
+
+<h3 id="overwrite-filter"><a href="#overwrite-filter">
+  Overwriting filter properties
+</a></h3>
+
+In Mongoose 4.x, overwriting a filter property that's a primitive with one that is an object would silently fail. For example, the below code would ignore the `where()` and be equivalent to `Sport.find({ name: 'baseball' })`
+
+```javascript
+Sport.find({ name: 'baseball' }).where({name: {$ne: 'softball'}});
+```
+
+In Mongoose 5.x, the above code will correctly overwrite `'baseball'` with `{ $ne: 'softball' }` 
+
+<h3 id="bulkwrite-results"><a href="#bulkwrite-results">
+  `bulkWrite()` results
+</a></h3>
+
+Mongoose 5.x uses version 3.x of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb). MongoDB driver 3.x changed the format of
+the result of [`bulkWrite()` calls](/docs/api.html#model_Model.bulkWrite) so there is no longer a top-level `nInserted`, `nModified`, etc. property. The new result object structure is [described here](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult).
+
+```javascript
+const Model = mongoose.model('Test', new Schema({ name: String }));
+
+const res = await Model.bulkWrite([{ insertOne: { document: { name: 'test' } } }]);
+
+console.log(res);
+```
+
+In Mongoose 4.x, the above will print:
+
+```
+BulkWriteResult {
+  ok: [Getter],
+  nInserted: [Getter],
+  nUpserted: [Getter],
+  nMatched: [Getter],
+  nModified: [Getter],
+  nRemoved: [Getter],
+  getInsertedIds: [Function],
+  getUpsertedIds: [Function],
+  getUpsertedIdAt: [Function],
+  getRawResponse: [Function],
+  hasWriteErrors: [Function],
+  getWriteErrorCount: [Function],
+  getWriteErrorAt: [Function],
+  getWriteErrors: [Function],
+  getLastOp: [Function],
+  getWriteConcernError: [Function],
+  toJSON: [Function],
+  toString: [Function],
+  isOk: [Function],
+  insertedCount: 1,
+  matchedCount: 0,
+  modifiedCount: 0,
+  deletedCount: 0,
+  upsertedCount: 0,
+  upsertedIds: {},
+  insertedIds: { '0': 5be9a3101638a066702a0d38 },
+  n: 1 }
+```
+
+In Mongoose 5.x, the script will print:
+
+```
+BulkWriteResult {
+  result: 
+  { ok: 1,
+    writeErrors: [],
+    writeConcernErrors: [],
+    insertedIds: [ [Object] ],
+    nInserted: 1,
+    nUpserted: 0,
+    nMatched: 0,
+    nModified: 0,
+    nRemoved: 0,
+    upserted: [],
+    lastOp: { ts: [Object], t: 1 } },
+  insertedCount: 1,
+  matchedCount: 0,
+  modifiedCount: 0,
+  deletedCount: 0,
+  upsertedCount: 0,
+  upsertedIds: {},
+  insertedIds: { '0': 5be9a1c87decfc6443dd9f18 },
+  n: 1 }
+```
+
+<h3 id="strict-ssl-validation"><a href="#strict-ssl-validation">
+  Strict SSL Validation
+</a></h3>
+
+The most recent versions of the [MongoDB Node.js driver use strict SSL validation by default](http://mongodb.github.io/node-mongodb-native/3.5/tutorials/connect/tls/),
+which may lead to errors if you're using [self-signed certificates](https://github.com/Automattic/mongoose/issues/9147).
+
+If this is blocking you from upgrading, you can set the `tlsInsecure` option to `true`.
+
+```javascript
+mongoose.connect(uri, { tlsInsecure: false }); // Opt out of additional SSL validation
+```
\ No newline at end of file
diff --git a/docs/migrating_to_5.pug b/docs/migrating_to_5.pug
deleted file mode 100644
index 9d675af697c..00000000000
--- a/docs/migrating_to_5.pug
+++ /dev/null
@@ -1,572 +0,0 @@
-extends layout
-
-block append style
-  style.
-    table td {
-      padding-right: 15px;
-    }
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  :markdown
-    ## Migrating from 4.x to 5.x
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    There are several [backwards-breaking changes](https://github.com/Automattic/mongoose/blob/master/History.md)
-    you should be aware of when migrating from Mongoose 4.x to Mongoose 5.x.
-
-    If you're still on Mongoose 3.x, please read the [Mongoose 3.x to 4.x migration guide](migration.html).
-
-    * [Version Requirements](#version-requirements)
-    * [Query Middleware](#query-middleware)
-    * [Promises and Callbacks for `mongoose.connect()`](#promises-and-callbacks)
-    * [Connection Logic and `useMongoClient`](#connection-logic)
-    * [Setter Order](#setter-order)
-    * [Checking if a path is populated](#id-getter)
-    * [Return Values for `remove()` and `deleteX()`](#return-value-for-delete)
-    * [Aggregation Cursors](#aggregation-cursors)
-    * [geoNear](#geonear)
-    * [Required URI encoding of connection strings](#uri-encoding)
-    * [Passwords which contain certain characters](#password-characters)
-    * [Domain sockets](#domain-sockets)
-    * [`toObject()` Options](#toobject-options)
-    * [Aggregate Parameters](#aggregate-parameters)
-    * [Boolean Casting](#boolean-casting)
-    * [Query Casting](#query-casting)
-    * [Post Save Hooks Get Flow Control](#post-save-flow-control)
-    * [The `$pushAll` Operator](#pushall)
-    * [Always Use Forward Key Order](#retain-key-order)
-    * [Run setters on queries](#run-setters-on-queries)
-    * [Pre-compiled Browser Bundle](#browser-bundle)
-    * [Save Errors](#save-errors)
-    * [Init hook signatures](#init-hooks)
-    * [`numAffected` and `save()`](#save-num-affected)
-    * [`remove()` and debouncing](#remove-debounce)
-    * [`getPromiseConstructor()`](#get-promise-constructor)
-    * [Passing Parameters from Pre Hooks](#pre-hook-params)
-    * [`required` validator for arrays](#array-required)
-    * [debug output defaults to stdout instead of stderr](#debug-output)
-    * [Overwriting filter properties](#overwrite-filter)
-    * [`bulkWrite()` results](#bulkwrite-results)
-    * [Strict SSL validation](#strict-ssl-validation)
-
-    <h3 id="version-requirements"><a href="#version-requirements">Version Requirements</a></h3>
-
-    Mongoose now requires Node.js >= 4.0.0 and MongoDB >= 3.0.0.
-    [MongoDB 2.6](https://www.mongodb.com/blog/post/mongodb-2-6-end-of-life) and
-    [Node.js < 4](https://github.com/nodejs/Release) where both EOL-ed in 2016.
-
-    <h3 id="query-middleware"><a href="#query-middleware">Query Middleware</a></h3>
-
-    Query middleware is now compiled when you call `mongoose.model()` or `db.model()`. If you add query middleware after calling `mongoose.model()`, that middleware will **not** get called.
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    const MyModel = mongoose.model('Test', schema);
-    schema.pre('find', () => { console.log('find!'); });
-
-    MyModel.find().exec(function() {
-      // In mongoose 4.x, the above `.find()` will print "find!"
-      // In mongoose 5.x, "find!" will **not** be printed.
-      // Call `pre('find')` **before** calling `mongoose.model()` to make the middleware apply.
-    });
-    ```
-
-    <h3 id="promises-and-callbacks"><a href="#promises-and-callbacks">
-      Promises and Callbacks for `mongoose.connect()`
-    </a></h3>
-
-    `mongoose.connect()` and `mongoose.disconnect()` now return a promise if no callback specified, or `null` otherwise. It does **not** return the mongoose singleton.
-
-    ```javascript
-    // Worked in mongoose 4. Does **not** work in mongoose 5, `mongoose.connect()`
-    // now returns a promise consistently. This is to avoid the horrible things
-    // we've done to allow mongoose to be a thenable that resolves to itself.
-    mongoose.connect('mongodb://localhost:27017/test').model('Test', new Schema({}));
-
-    // Do this instead
-    mongoose.connect('mongodb://localhost:27017/test');
-    mongoose.model('Test', new Schema({}));
-    ```
-
-    <h3 id="connection-logic"><a href="#connection-logic">
-      Connection Logic and `useMongoClient`
-    </a></h3>
-
-    The [`useMongoClient` option](/docs/4.x/docs/connections.html#use-mongo-client) was
-    removed in Mongoose 5, it is now always `true`. As a consequence, Mongoose 5
-    no longer supports several function signatures for `mongoose.connect()` that
-    worked in Mongoose 4.x if the `useMongoClient` option was off. Below are some
-    examples of `mongoose.connect()` calls that do **not** work in Mongoose 5.x.
-
-    * `mongoose.connect('localhost', 27017);`
-    * `mongoose.connect('localhost', 'mydb', 27017);`
-    * `mongoose.connect('mongodb://host1:27017,mongodb://host2:27017');`
-
-    In Mongoose 5.x, the first parameter to `mongoose.connect()` and `mongoose.createConnection()`, if specified, **must** be a [MongoDB connection string](https://docs.mongodb.com/manual/reference/connection-string/). The
-    connection string and options are then passed down to [the MongoDB Node.js driver's `MongoClient.connect()` function](http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html#.connect). Mongoose does not modify the connection string, although `mongoose.connect()` and `mongoose.createConnection()` support a [few additional options in addition to the ones the MongoDB driver supports](http://mongoosejs.com/docs/connections.html#options).
-
-    <h3 id="setter-order"><a href="#setter-order">
-      Setter Order
-    </a></h3>
-
-    Setters run in reverse order in 4.x:
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    schema.path('name').
-      set(() => console.log('This will print 2nd')).
-      set(() => console.log('This will print first'));
-    ```
-
-    In 5.x, setters run in the order they're declared.
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    schema.path('name').
-      set(() => console.log('This will print first')).
-      set(() => console.log('This will print 2nd'));
-    ```
-
-    <h3 id="id-getter"><a href="#id-getter">
-      Checking if a path is populated
-    </a></h3>
-
-    Mongoose 5.1.0 introduced an `_id` getter to ObjectIds that lets you get an ObjectId regardless of whether a path
-    is populated.
-
-    ```javascript
-    const blogPostSchema = new Schema({
-      title: String,
-      author: {
-        type: mongoose.Schema.Types.ObjectId,
-        ref: 'Author'
-      }
-    });
-    const BlogPost = mongoose.model('BlogPost', blogPostSchema);
-
-    await BlogPost.create({ title: 'test', author: author._id });
-    const blogPost = await BlogPost.findOne();
-
-    console.log(blogPost.author); // '5b207f84e8061d1d2711b421'
-    // New in Mongoose 5.1.0: this will print '5b207f84e8061d1d2711b421' as well
-    console.log(blogPost.author._id);
-
-    await blogPost.populate('author');
-    console.log(blogPost.author._id); '5b207f84e8061d1d2711b421'
-    ```
-
-    As a consequence, checking whether `blogPost.author._id` is [no longer viable as a way to check whether `author` is populated](https://github.com/Automattic/mongoose/issues/6415#issuecomment-388579185). Use `blogPost.populated('author') != null` or `blogPost.author instanceof mongoose.Types.ObjectId` to check whether `author` is populated instead.
-
-    Note that you can call `mongoose.set('objectIdGetter', false)` to change this behavior.
-
-    <h3 id="return-value-for-delete"><a href="#return-value-for-delete">
-      Return Values for `remove()` and `deleteX()`
-    </a></h3>
-
-    `deleteOne()`, `deleteMany()`, and `remove()` now resolve to the result object
-    rather than the full [driver `WriteOpResult` object](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#~writeOpCallback).
-
-    ```javascript
-    // In 4.x, this is how you got the number of documents deleted
-    MyModel.deleteMany().then(res => console.log(res.result.n));
-    // In 5.x this is how you get the number of documents deleted
-    MyModel.deleteMany().then(res => res.n);
-    ```
-
-    <h3 id="aggregation-cursors"><a href="#aggregation-cursors">
-      Aggregation Cursors
-    </a></h3>
-
-    The `useMongooseAggCursor` option from 4.x is now always on. This is the new syntax for aggregation cursors in mongoose 5:
-
-    ```javascript
-    // When you call `.cursor()`, `.exec()` will now return a mongoose aggregation
-    // cursor.
-    const cursor = MyModel.aggregate([{ $match: { name: 'Val' } }]).cursor().exec();
-    // No need to `await` on the cursor or wait for a promise to resolve
-    cursor.eachAsync(doc => console.log(doc));
-
-    // Can also pass options to `cursor()`
-    const cursorWithOptions = MyModel.
-      aggregate([{ $match: { name: 'Val' } }]).
-      cursor({ batchSize: 10 }).
-      exec();
-    ```
-
-    <h3 id="geonear"><a href="#geonear">
-      geoNear
-    </a></h3>
-
-    `Model.geoNear()` has been removed because the [MongoDB driver no longer supports it](https://github.com/mongodb/node-mongodb-native/blob/master/CHANGES_3.0.0.md#geonear-command-helper)
-
-    <h3 id="uri-encoding"><a href="#uri-encoding">
-      Required URI encoding of connection strings
-    </a></h3>
-
-    Due to changes in the MongoDB driver, connection strings must be URI encoded.
-
-    If they are not, connections may fail with an illegal character message.
-
-    <h3 id="password-characters"><a href="#password-characters">
-      Passwords which contain certain characters
-    </a></h3>
-
-    See a [full list of affected characters](https://developer.mozilla.org/en-US/docs/Glossary/percent-encoding).
-
-    If your app is used by a lot of different connection strings, it's possible
-    that your test cases will pass, but production passwords will fail. Encode all your connection
-    strings to be safe.
-
-    If you want to continue to use unencoded connection strings, the easiest fix is to use
-    the `mongodb-uri` module to parse the connection strings, and then produce the properly encoded
-    versions. You can use a function like this:
-
-    ```javascript
-    const uriFormat = require('mongodb-uri')
-    function encodeMongoURI (urlString) {
-        if (urlString) {
-          let parsed = uriFormat.parse(urlString)
-          urlString = uriFormat.format(parsed);
-        }
-        return urlString;
-      }
-    }
-
-    // Your un-encoded string.
-    const mongodbConnectString = "mongodb://...";
-    mongoose.connect(encodeMongoURI(mongodbConnectString))
-    ```
-
-    The function above is safe to use whether the existing string is already encoded or not.
-
-    <h3 id="domain-sockets"><a href="#domain-sockets">
-      Domain sockets
-    </a></h3>
-
-    Domain sockets must be URI encoded. For example:
-
-    ```javascript
-    // Works in mongoose 4. Does **not** work in mongoose 5 because of more
-    // stringent URI parsing.
-    const host = '/tmp/mongodb-27017.sock';
-    mongoose.createConnection(`mongodb://aaron:psw@${host}/fake`);
-
-    // Do this instead
-    const host = encodeURIComponent('/tmp/mongodb-27017.sock');
-    mongoose.createConnection(`mongodb://aaron:psw@${host}/fake`);
-    ```
-
-    <h3 id="toobject-options"><a href="#toobject-options">
-      `toObject()` Options
-    </a></h3>
-
-    The `options` parameter to `toObject()` and `toJSON()` merge defaults rather than overwriting them.
-
-    ```javascript
-    // Note the `toObject` option below
-    const schema = new Schema({ name: String }, { toObject: { virtuals: true } });
-    schema.virtual('answer').get(() => 42);
-    const MyModel = db.model('MyModel', schema);
-
-    const doc = new MyModel({ name: 'test' });
-    // In mongoose 4.x this prints "undefined", because `{ minimize: false }`
-    // overwrites the entire schema-defined options object.
-    // In mongoose 5.x this prints "42", because `{ minimize: false }` gets
-    // merged with the schema-defined options.
-    console.log(doc.toJSON({ minimize: false }).answer);
-    ```
-
-    <h3 id="aggregate-parameters"><a href="#aggregate-parameters">
-      Aggregate Parameters
-    </a></h3>
-
-    `aggregate()` no longer accepts a spread, you **must** pass your aggregation pipeline as an array. The below code worked in 4.x:
-
-    ```javascript
-    MyModel.aggregate({ $match: { isDeleted: false } }, { $skip: 10 }).exec(cb);
-    ```
-
-    The above code does **not** work in 5.x, you **must** wrap the `$match` and `$skip` stages in an array.
-
-    ```javascript
-    MyModel.aggregate([{ $match: { isDeleted: false } }, { $skip: 10 }]).exec(cb);
-    ```
-
-    <h3 id="boolean-casting"><a href="#boolean-casting">
-      Boolean Casting
-    </a></h3>
-
-    By default, mongoose 4 would coerce any value to a boolean without error.
-
-    ```javascript
-    // Fine in mongoose 4, would save a doc with `boolField = true`
-    const MyModel = mongoose.model('Test', new Schema({
-      boolField: Boolean
-    }));
-
-    MyModel.create({ boolField: 'not a boolean' });
-    ```
-
-    Mongoose 5 only casts the following values to `true`:
-
-    * `true`
-    * `'true'`
-    * `1`
-    * `'1'`
-    * `'yes'`
-
-    And the following values to `false`:
-
-    * `false`
-    * `'false'`
-    * `0`
-    * `'0'`
-    * `'no'`
-
-    All other values will cause a `CastError`
-
-    <h3 id="query-casting"><a href="#query-casting">
-      Query Casting
-    </a></h3>
-
-    Casting for `update()`, `updateOne()`, `updateMany()`, `replaceOne()`,
-    `remove()`, `deleteOne()`, and `deleteMany()` doesn't happen until `exec()`.
-    This makes it easier for hooks and custom query helpers to modify data, because
-    mongoose won't restructure the data you passed in until after your hooks and
-    query helpers have ran. It also makes it possible to set the `overwrite` option
-    _after_ passing in an update.
-
-    ```javascript
-    // In mongoose 4.x, this becomes `{ $set: { name: 'Baz' } }` despite the `overwrite`
-    // In mongoose 5.x, this overwrite is respected and the first document with
-    // `name = 'Bar'` will be replaced with `{ name: 'Baz' }`
-    User.where({ name: 'Bar' }).update({ name: 'Baz' }).setOptions({ overwrite: true });
-    ```
-
-    <h3 id="post-save-flow-control"><a href="#post-save-flow-control">
-      Post Save Hooks Get Flow Control
-    </a></h3>
-
-    Post hooks now get flow control, which means async post save hooks and child document post save hooks execute **before** your `save()` callback.
-
-    ```javascript
-    const ChildModelSchema = new mongoose.Schema({
-      text: {
-        type: String
-      }
-    });
-    ChildModelSchema.post('save', function(doc) {
-      // In mongoose 5.x this will print **before** the `console.log()`
-      // in the `save()` callback. In mongoose 4.x this was reversed.
-      console.log('Child post save');
-    });
-    const ParentModelSchema = new mongoose.Schema({
-      children: [ChildModelSchema]
-    });
-
-    const Model = mongoose.model('Parent', ParentModelSchema);
-    const m = new Model({ children: [{ text: 'test' }] });
-    m.save(function() {
-      // In mongoose 5.xm this prints **after** the "Child post save" message.
-      console.log('Save callback');
-    });
-    ```
-
-    <h3 id="pushall"><a href="#pushall">
-      The `$pushAll` Operator
-    </a></h3>
-
-    `$pushAll` is no longer supported and no longer used internally for `save()`, since it has been [deprecated since MongoDB 2.4](https://docs.mongodb.com/manual/reference/operator/update/pushAll/). Use `$push` with `$each` instead.
-
-    <h3 id="retain-key-order"><a href="#retain-key-order">
-      Always Use Forward Key Order
-    </a></h3>
-
-    The `retainKeyOrder` option was removed, mongoose will now always retain the same key position when cloning objects. If you have queries or indexes that rely on reverse key order, you will have to change them.
-
-    <h3 id="run-setters-on-queries"><a href="#run-setters-on-queries">
-      Run setters on queries
-    </a></h3>
-
-    Setters now run on queries by default, and the old `runSettersOnQuery` option
-    has been removed.
-
-    ```javascript
-    const schema = new Schema({
-      email: { type: String, lowercase: true }
-    });
-    const Model = mongoose.model('Test', schema);
-    Model.find({ email: 'FOO@BAR.BAZ' }); // Converted to `find({ email: 'foo@bar.baz' })`
-    ```
-
-    <h3 id="browser-bundle"><a href="#browser-bundle">
-      Pre-compiled Browser Bundle
-    </a></h3>
-
-    We no longer have a pre-compiled version of mongoose for the browser. If you want to use mongoose schemas in the browser, you need to build your own bundle with browserify/webpack.
-
-    <h3 id="save-errors"><a href="#save-errors">
-      Save Errors
-    </a></h3>
-
-    The `saveErrorIfNotFound` option was removed, mongoose will now always error out from `save()` if the underlying document was not found
-
-    <h3 id="init-hooks"><a href="#init-hooks">
-      Init hook signatures
-    </a></h3>
-
-    `init` hooks are now fully synchronous and do not receive `next()` as a parameter.
-
-    `Document.prototype.init()` no longer takes a callback as a parameter. It
-    was always synchronous, just had a callback for legacy reasons.
-
-    <h3 id="save-num-affected"><a href="#save-num-affected">
-      `numAffected` and `save()`
-    </a></h3>
-
-    `doc.save()` no longer passes `numAffected` as a 3rd param to its callback.
-
-    <h3 id="remove-debounce"><a href="#remove-debounce">
-      `remove()` and debouncing
-    </a></h3>
-
-    `doc.remove()` no longer debounces
-
-    <h3 id="get-promise-constructor"><a href="#get-promise-constructor">
-      `getPromiseConstructor()`
-    </a></h3>
-
-    `getPromiseConstructor()` is gone, just use `mongoose.Promise`.
-
-    <h3 id="pre-hook-params"><a href="#pre-hook-params">
-      Passing Parameters from Pre Hooks
-    </a></h3>
-
-    You cannot pass parameters to the next pre middleware in the chain using `next()` in mongoose 5.x. In mongoose 4, `next('Test')` in pre middleware would call the
-    next middleware with 'Test' as a parameter. Mongoose 5.x has removed support for this.
-
-    <h3 id="array-required"><a href="#array-required">
-      `required` validator for arrays
-    </a></h3>
-
-    In mongoose 5 the `required` validator only verifies if the value is an
-    array. That is, it will **not** fail for _empty_ arrays as it would in
-    mongoose 4.
-
-    <h3 id="debug-output"><a href="#debug-output">
-      debug output defaults to stdout instead of stderr
-    </a></h3>
-
-    In mongoose 5 the default debug function uses `console.info()` to display messages instead of `console.error()`.
-
-    <h3 id="overwrite-filter"><a href="#overwrite-filter">
-      Overwriting filter properties
-    </a></h3>
-
-    In Mongoose 4.x, overwriting a filter property that's a primitive with one that is an object would silently fail. For example, the below code would ignore the `where()` and be equivalent to `Sport.find({ name: 'baseball' })`
-
-    ```javascript
-    Sport.find({ name: 'baseball' }).where({name: {$ne: 'softball'}});
-    ```
-
-    In Mongoose 5.x, the above code will correctly overwrite `'baseball'` with `{ $ne: 'softball' }` 
-
-    <h3 id="bulkwrite-results"><a href="#bulkwrite-results">
-      `bulkWrite()` results
-    </a></h3>
-
-    Mongoose 5.x uses version 3.x of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb). MongoDB driver 3.x changed the format of
-    the result of [`bulkWrite()` calls](/docs/api.html#model_Model.bulkWrite) so there is no longer a top-level `nInserted`, `nModified`, etc. property. The new result object structure is [described here](http://mongodb.github.io/node-mongodb-native/3.1/api/Collection.html#~BulkWriteOpResult).
-
-    ```javascript
-    const Model = mongoose.model('Test', new Schema({ name: String }));
-
-    const res = await Model.bulkWrite([{ insertOne: { document: { name: 'test' } } }]);
-
-    console.log(res);
-    ```
-
-    In Mongoose 4.x, the above will print:
-
-    ```
-    BulkWriteResult {
-      ok: [Getter],
-      nInserted: [Getter],
-      nUpserted: [Getter],
-      nMatched: [Getter],
-      nModified: [Getter],
-      nRemoved: [Getter],
-      getInsertedIds: [Function],
-      getUpsertedIds: [Function],
-      getUpsertedIdAt: [Function],
-      getRawResponse: [Function],
-      hasWriteErrors: [Function],
-      getWriteErrorCount: [Function],
-      getWriteErrorAt: [Function],
-      getWriteErrors: [Function],
-      getLastOp: [Function],
-      getWriteConcernError: [Function],
-      toJSON: [Function],
-      toString: [Function],
-      isOk: [Function],
-      insertedCount: 1,
-      matchedCount: 0,
-      modifiedCount: 0,
-      deletedCount: 0,
-      upsertedCount: 0,
-      upsertedIds: {},
-      insertedIds: { '0': 5be9a3101638a066702a0d38 },
-      n: 1 }
-    ```
-
-    In Mongoose 5.x, the script will print:
-
-    ```
-    BulkWriteResult {
-      result: 
-      { ok: 1,
-        writeErrors: [],
-        writeConcernErrors: [],
-        insertedIds: [ [Object] ],
-        nInserted: 1,
-        nUpserted: 0,
-        nMatched: 0,
-        nModified: 0,
-        nRemoved: 0,
-        upserted: [],
-        lastOp: { ts: [Object], t: 1 } },
-      insertedCount: 1,
-      matchedCount: 0,
-      modifiedCount: 0,
-      deletedCount: 0,
-      upsertedCount: 0,
-      upsertedIds: {},
-      insertedIds: { '0': 5be9a1c87decfc6443dd9f18 },
-      n: 1 }
-    ```
-
-    <h3 id="strict-ssl-validation"><a href="#strict-ssl-validation">
-      Strict SSL Validation
-    </a></h3>
-
-    The most recent versions of the [MongoDB Node.js driver use strict SSL validation by default](http://mongodb.github.io/node-mongodb-native/3.5/tutorials/connect/tls/),
-    which may lead to errors if you're using [self-signed certificates](https://github.com/Automattic/mongoose/issues/9147).
-
-    If this is blocking you from upgrading, you can set the `tlsInsecure` option to `true`.
-
-    ```javascript
-    mongoose.connect(uri, { tlsInsecure: false }); // Opt out of additional SSL validation
-    ```
diff --git a/docs/source/index.js b/docs/source/index.js
index a4b85f6a868..44d4f76f1a3 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -2,7 +2,7 @@
 'use strict';
 exports['index.pug'] = require('./home');
 exports['docs/api.pug'] = require('./api');
-exports['docs/browser.pug'] = { guide: true, title: 'Browser Library', acquit: true };
+exports['docs/browser.md'] = { guide: true, title: 'Browser Library', acquit: true, markdown: true };
 exports['docs/index.pug'] = { title: 'Getting Started' };
 exports['docs/production.pug'] = require('./production');
 exports['docs/prior.pug'] = require('./prior');
@@ -17,22 +17,23 @@ exports['docs/models.pug'] = { guide: true, title: 'Models' };
 exports['docs/queries.pug'] = { guide: true, title: 'Queries' };
 exports['docs/populate.pug'] = { guide: true, title: 'Query Population' };
 exports['docs/migration.pug'] = { guide: true, title: 'Migration Guide' };
-exports['docs/migrating_to_5.pug'] = { guide: true, title: 'Migrating to Mongoose 5' };
-exports['docs/contributing.pug'] = { guide: true, title: 'Contributing' };
-exports['docs/connections.pug'] = { guide: true, title: 'Connecting to MongoDB' };
-exports['docs/lambda.pug'] = { guide: true, title: 'Using Mongoose With AWS Lambda' };
-exports['docs/geojson.pug'] = { guide: true, title: 'Using GeoJSON', acquit: true };
-exports['docs/transactions.pug'] = { guide: true, title: 'Transactions', acquit: true };
-exports['docs/deprecations.pug'] = { guide: true, title: 'Deprecation Warnings' };
-exports['docs/further_reading.pug'] = { title: 'Further Reading' };
-exports['docs/jest.pug'] = { title: 'Testing Mongoose with Jest' };
-exports['docs/faq.pug'] = { guide: true, title: 'FAQ' };
-exports['docs/typescript.pug'] = { guide: true, title: 'Using TypeScript with Mongoose' };
-exports['docs/compatibility.pug'] = {
+exports['docs/migrating_to_5.md'] = { guide: true, title: 'Migrating to Mongoose 5', markdown: true };
+exports['docs/contributing.md'] = { guide: true, title: 'Contributing', markdown: true };
+exports['docs/connections.md'] = { guide: true, title: 'Connecting to MongoDB', markdown: true };
+exports['docs/lambda.md'] = { guide: true, title: 'Using Mongoose With AWS Lambda', markdown: true };
+exports['docs/geojson.md'] = { guide: true, title: 'Using GeoJSON', acquit: true, markdown: true };
+exports['docs/transactions.md'] = { guide: true, title: 'Transactions', acquit: true, markdown: true };
+exports['docs/deprecations.md'] = { guide: true, title: 'Deprecation Warnings', markdown: true };
+exports['docs/further_reading.md'] = { title: 'Further Reading', markdown: true };
+exports['docs/jest.md'] = { title: 'Testing Mongoose with Jest', markdown: true };
+exports['docs/faq.md'] = { guide: true, title: 'FAQ', markdown: true };
+exports['docs/typescript.md'] = { guide: true, title: 'Using TypeScript with Mongoose', markdown: true };
+exports['docs/compatibility.md'] = {
   title: 'MongoDB Version Compatibility',
-  guide: true
+  guide: true,
+  markdown: true
 };
 exports['docs/search.pug'] = { title: 'Search' };
-exports['docs/enterprise.pug'] = { title: 'Mongoose for Enterprise' };
-exports['docs/built-with-mongoose.pug'] = { title: 'Built with Mongoose' };
+exports['docs/enterprise.md'] = { title: 'Mongoose for Enterprise', markdown: true };
+exports['docs/built-with-mongoose.md'] = { title: 'Built with Mongoose', markdown: true };
 exports['docs/async-await.md'] = { title: 'Using Async/Await with Mongoose', markdown: true };
\ No newline at end of file
diff --git a/docs/transactions.md b/docs/transactions.md
new file mode 100644
index 00000000000..75f2fecc964
--- /dev/null
+++ b/docs/transactions.md
@@ -0,0 +1,76 @@
+# Transactions in Mongoose
+
+[Transactions](https://www.mongodb.com/transactions) are new in MongoDB
+4.0 and Mongoose 5.2.0. Transactions let you execute multiple operations
+in isolation and potentially undo all the operations if one of them fails.
+This guide will get you started using transactions with Mongoose.
+
+<h2 id="getting-started-with-transactions"><a href="#getting-started-with-transactions">Getting Started with Transactions</a></h2>
+
+To create a transaction, you first need to create a session using or [`Mongoose#startSession`](/docs/api/mongoose.html#mongoose_Mongoose-startSession)
+or [`Connection#startSession()`](/docs/api/connection.html#connection_Connection-startSession).
+
+```javascript
+const session = await mongoose.startSession();
+```
+
+In practice, you should use either the [`session.withTransaction()` helper](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction)
+or Mongoose's `Connection#transaction()` function to run a transaction. The `session.withTransaction()` helper handles:
+
+- Creating a transaction
+- Committing the transaction if it succeeds
+- Aborting the transaction if your operation throws
+- Retrying in the event of a [transient transaction error](https://stackoverflow.com/questions/52153538/what-is-a-transienttransactionerror-in-mongoose-or-mongodb).
+
+```javascript
+[require:transactions.*withTransaction]
+```
+
+For more information on the `ClientSession#withTransaction()` function, please see
+[the MongoDB Node.js driver docs](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction).
+
+Mongoose's `Connection#transaction()` function is a wrapper around `withTransaction()` that
+integrates Mongoose change tracking with transactions. For example, the `Connection#transaction()`
+function handles resetting a document if you `save()` that document in a transaction that later fails.
+
+```javascript
+[require:transactions.*can save document after aborted transaction]
+```
+
+<h2 id="with-mongoose-documents-and-save"><a href="#with-mongoose-documents-and-save">With Mongoose Documents and <code>save()</code></a></h2>
+
+If you get a [Mongoose document](/docs/documents.html) from [`findOne()`](/docs/api.html#findone_findOne)
+or [`find()`](/docs/api.html#find_find) using a session, the document will
+keep a reference to the session and use that session for [`save()`](/docs/api.html#document_Document-save).
+
+To get/set the session associated with a given document, use [`doc.$session()`](/docs/api.html#document_Document-$session).
+
+```javascript
+[require:transactions.*save]
+```
+
+<h2 id="with-the-aggregation-framework"><a href="#with-the-aggregation-framework">With the Aggregation Framework</a></h2>
+
+The `Model.aggregate()` function also supports transactions. Mongoose
+aggregations have a [`session()` helper](/docs/api.html#aggregate_Aggregate-session)
+that sets the [`session` option](/docs/api.html#aggregate_Aggregate-option).
+Below is an example of executing an aggregation within a transaction.
+
+```javascript
+[require:transactions.*aggregate]
+```
+
+<h2 id="advanced-usage"><a href="#advanced-usage">Advanced Usage</a></h2>
+
+Advanced users who want more fine-grained control over when they commit or abort transactions
+can use `session.startTransaction()` to start a transaction:
+
+```javascript
+[require:transactions.*basic example]
+```
+
+You can also use `session.abortTransaction()` to abort a transaction:
+
+```javascript
+[require:transactions.*abort]
+```
\ No newline at end of file
diff --git a/docs/transactions.pug b/docs/transactions.pug
deleted file mode 100644
index df31b1590d6..00000000000
--- a/docs/transactions.pug
+++ /dev/null
@@ -1,98 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet" href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    # Transactions in Mongoose
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    [Transactions](https://www.mongodb.com/transactions) are new in MongoDB
-    4.0 and Mongoose 5.2.0. Transactions let you execute multiple operations
-    in isolation and potentially undo all the operations if one of them fails.
-    This guide will get you started using transactions with Mongoose.
-
-    <h2 id="getting-started-with-transactions"><a href="#getting-started-with-transactions">Getting Started with Transactions</a></h2>
-
-    To create a transaction, you first need to create a session using or [`Mongoose#startSession`](/docs/api/mongoose.html#mongoose_Mongoose-startSession)
-    or [`Connection#startSession()`](/docs/api/connection.html#connection_Connection-startSession).
-
-    ```javascript
-    const session = await mongoose.startSession();
-    ```
-
-    In practice, you should use either the [`session.withTransaction()` helper](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction)
-    or Mongoose's `Connection#transaction()` function to run a transaction. The `session.withTransaction()` helper handles:
-    
-    - Creating a transaction
-    - Committing the transaction if it succeeds
-    - Aborting the transaction if your operation throws
-    - Retrying in the event of a [transient transaction error](https://stackoverflow.com/questions/52153538/what-is-a-transienttransactionerror-in-mongoose-or-mongodb).
-
-    ```javascript
-    [require:transactions.*withTransaction]
-    ```
-
-    For more information on the `ClientSession#withTransaction()` function, please see
-    [the MongoDB Node.js driver docs](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction). 
-
-    Mongoose's `Connection#transaction()` function is a wrapper around `withTransaction()` that
-    integrates Mongoose change tracking with transactions. For example, the `Connection#transaction()`
-    function handles resetting a document if you `save()` that document in a transaction that later fails.
-
-    ```javascript
-    [require:transactions.*can save document after aborted transaction]
-    ```
-
-    <h2 id="with-mongoose-documents-and-save"><a href="#with-mongoose-documents-and-save">With Mongoose Documents and <code>save()</code></a></h2>
-
-    If you get a [Mongoose document](/docs/documents.html) from [`findOne()`](/docs/api.html#findone_findOne)
-    or [`find()`](/docs/api.html#find_find) using a session, the document will
-    keep a reference to the session and use that session for [`save()`](/docs/api.html#document_Document-save).
-
-    To get/set the session associated with a given document, use [`doc.$session()`](/docs/api.html#document_Document-$session).
-
-    ```javascript
-    [require:transactions.*save]
-    ```
-
-    <h2 id="with-the-aggregation-framework"><a href="#with-the-aggregation-framework">With the Aggregation Framework</a></h2>
-
-    The `Model.aggregate()` function also supports transactions. Mongoose
-    aggregations have a [`session()` helper](/docs/api.html#aggregate_Aggregate-session)
-    that sets the [`session` option](/docs/api.html#aggregate_Aggregate-option).
-    Below is an example of executing an aggregation within a transaction.
-
-    ```javascript
-    [require:transactions.*aggregate]
-    ```
-
-    <h2 id="advanced-usage"><a href="#advanced-usage">Advanced Usage</a></h2>
-
-    Advanced users who want more fine-grained control over when they commit or abort transactions
-    can use `session.startTransaction()` to start a transaction:
-
-    ```javascript
-    [require:transactions.*basic example]
-    ```
-
-    You can also use `session.abortTransaction()` to abort a transaction:
-
-    ```javascript
-    [require:transactions.*abort]
-    ```
\ No newline at end of file
diff --git a/docs/typescript.md b/docs/typescript.md
new file mode 100644
index 00000000000..3149e67a207
--- /dev/null
+++ b/docs/typescript.md
@@ -0,0 +1,93 @@
+# TypeScript Support
+
+Mongoose introduced [officially supported TypeScript bindings in v5.11.0](https://thecodebarbarian.com/working-with-mongoose-in-typescript.html).
+Mongoose's `index.d.ts` file supports a wide variety of syntaxes and strives to be compatible with `@types/mongoose` where possible.
+This guide describes Mongoose's recommended approach to working with Mongoose in TypeScript.
+
+### Creating Your First Document
+
+To get started with Mongoose in TypeScript, you need to: 
+
+1. Create an interface representing a document in MongoDB.
+2. Create a [Schema](/docs/guide.html) corresponding to the document interface.
+3. Create a Model.
+4. [Connect to MongoDB](/docs/connections.html).
+
+```typescript
+import { Schema, model, connect } from 'mongoose';
+
+// 1. Create an interface representing a document in MongoDB.
+interface User {
+  name: string;
+  email: string;
+  avatar?: string;
+}
+
+// 2. Create a Schema corresponding to the document interface.
+const schema = new Schema<User>({
+  name: { type: String, required: true },
+  email: { type: String, required: true },
+  avatar: String
+});
+
+// 3. Create a Model.
+const UserModel = model<User>('User', schema);
+
+run().catch(err => console.log(err));
+
+async function run(): Promise<void> {
+  // 4. Connect to MongoDB
+  await connect('mongodb://localhost:27017/test', {
+    useNewUrlParser: true,
+    useUnifiedTopology: true
+  });
+
+  const doc = new UserModel({
+    name: 'Bill',
+    email: 'bill@initech.com',
+    avatar: 'https://i.imgur.com/dM7Thhn.png'
+  });
+  await doc.save();
+
+  console.log(doc.email); // 'bill@initech.com'
+}
+```
+
+You as the developer are responsible for ensuring that your document interface lines up with your Mongoose schema.
+For example, Mongoose won't report an error if `email` is `required` in your Mongoose schema but optional in your document interface.
+
+### Using `extends Document`
+
+Alternatively, your document interface can extend Mongoose's `Document` class.
+Many Mongoose TypeScript codebases use the below approach.
+
+```typescript
+import { Document, Schema, model, connect } from 'mongoose';
+
+interface User extends Document {
+  name: string;
+  email: string;
+  avatar?: string;
+}
+```
+
+This approach works, but we recommend your document interface _not_ extend `Document`.
+Using `extends Document` makes it difficult for Mongoose to infer which properties are present on [query filters](/docs/queries.html), [lean documents](/docs/tutorials/lean.html), and other cases.
+
+We recommend your document interface contain the properties defined in your schema and line up with what your documents look like in MongoDB.
+Although you can add [instance methods](/docs/guide.html#methods) to your document interface, we do not recommend doing so.
+
+### Using Custom Bindings
+
+If Mongoose's built-in `index.d.ts` file does not work for you, you can remove it in a postinstall script in your `package.json` as shown below.
+However, before you do, please [open an issue on Mongoose's GitHub page](https://github.com/Automattic/mongoose/issues/new) and describe the issue you're experiencing.
+
+```
+{
+  "postinstall": "rm ./node_modules/mongoose/index.d.ts"
+}
+```
+
+### Next Up
+
+Now that you've seen the basics of how to use Mongoose in TypeScript, let's take a look at [statics in TypeScript](/docs/typescript/statics.html).
\ No newline at end of file
diff --git a/docs/typescript.pug b/docs/typescript.pug
deleted file mode 100644
index a8f6cd2866c..00000000000
--- a/docs/typescript.pug
+++ /dev/null
@@ -1,101 +0,0 @@
-extends layout
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## TypeScript Support
-
-    Mongoose introduced [officially supported TypeScript bindings in v5.11.0](https://thecodebarbarian.com/working-with-mongoose-in-typescript.html).
-    Mongoose's `index.d.ts` file supports a wide variety of syntaxes and strives to be compatible with `@types/mongoose` where possible.
-    This guide describes Mongoose's recommended approach to working with Mongoose in TypeScript.
-
-    ### Creating Your First Document
-
-    To get started with Mongoose in TypeScript, you need to: 
-
-    1. Create an interface representing a document in MongoDB.
-    2. Create a [Schema](/docs/guide.html) corresponding to the document interface.
-    3. Create a Model.
-    4. [Connect to MongoDB](/docs/connections.html).
-
-    ```typescript
-    import { Schema, model, connect } from 'mongoose';
-
-    // 1. Create an interface representing a document in MongoDB.
-    interface User {
-      name: string;
-      email: string;
-      avatar?: string;
-    }
-
-    // 2. Create a Schema corresponding to the document interface.
-    const schema = new Schema<User>({
-      name: { type: String, required: true },
-      email: { type: String, required: true },
-      avatar: String
-    });
-
-    // 3. Create a Model.
-    const UserModel = model<User>('User', schema);
-
-    run().catch(err => console.log(err));
-
-    async function run(): Promise<void> {
-      // 4. Connect to MongoDB
-      await connect('mongodb://localhost:27017/test', {
-        useNewUrlParser: true,
-        useUnifiedTopology: true
-      });
-
-      const doc = new UserModel({
-        name: 'Bill',
-        email: 'bill@initech.com',
-        avatar: 'https://i.imgur.com/dM7Thhn.png'
-      });
-      await doc.save();
-
-      console.log(doc.email); // 'bill@initech.com'
-    }
-    ```
-
-    You as the developer are responsible for ensuring that your document interface lines up with your Mongoose schema.
-    For example, Mongoose won't report an error if `email` is `required` in your Mongoose schema but optional in your document interface.
-
-    ### Using `extends Document`
-
-    Alternatively, your document interface can extend Mongoose's `Document` class.
-    Many Mongoose TypeScript codebases use the below approach.
-
-    ```typescript
-    import { Document, Schema, model, connect } from 'mongoose';
-
-    interface User extends Document {
-      name: string;
-      email: string;
-      avatar?: string;
-    }
-    ```
-
-    This approach works, but we recommend your document interface _not_ extend `Document`.
-    Using `extends Document` makes it difficult for Mongoose to infer which properties are present on [query filters](/docs/queries.html), [lean documents](/docs/tutorials/lean.html), and other cases.
-
-    We recommend your document interface contain the properties defined in your schema and line up with what your documents look like in MongoDB.
-    Although you can add [instance methods](/docs/guide.html#methods) to your document interface, we do not recommend doing so.
-
-    ### Using Custom Bindings
-
-    If Mongoose's built-in `index.d.ts` file does not work for you, you can remove it in a postinstall script in your `package.json` as shown below.
-    However, before you do, please [open an issue on Mongoose's GitHub page](https://github.com/Automattic/mongoose/issues/new) and describe the issue you're experiencing.
-
-    ```
-    {
-      "postinstall": "rm ./node_modules/mongoose/index.d.ts"
-    }
-    ```
-
-    ### Next Up
-
-    Now that you've seen the basics of how to use Mongoose in TypeScript, let's take a look at [statics in TypeScript](/docs/typescript/statics.html).

From 0a8be0d5ce93ea80c4b415bfa9c42cb7b32a18e7 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 19 May 2021 18:02:07 -0400
Subject: [PATCH 2058/2348] 1 step forward

---
 lib/document.js | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 5d11879b455..f7a3d66a7b5 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2406,6 +2406,10 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       (typeof options === 'object') &&
       ('validateModifiedOnly' in options);
 
+  const pathsToSkip = options &&
+      (typeof options === 'object') &&
+      ('pathsToSkip' in options);
+
   let shouldValidateModifiedOnly;
   if (hasValidateModifiedOnlyOption) {
     shouldValidateModifiedOnly = !!options.validateModifiedOnly;
@@ -2455,10 +2459,16 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     pathDetails[0].filter((path) => this.isModified(path)) :
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
-
   if (typeof pathsToValidate === 'string') {
     pathsToValidate = pathsToValidate.split(' ');
   }
+  if (pathsToSkip) {
+    // call _handlePathsToValidate here
+    // console.log(paths);
+    // console.log(options);
+    // make a new variable that is paths intersection !options.pathsToSkip
+    // paths = _handlePathsToValidate(paths, newVar)
+  }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }

From 741e8fb9fa4dd9f89107f8e965277f5718bf9fb0 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 20 May 2021 10:56:08 -0400
Subject: [PATCH 2059/2348] finish

---
 lib/document.js | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index f7a3d66a7b5..13161bbae7f 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2463,11 +2463,14 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     pathsToValidate = pathsToValidate.split(' ');
   }
   if (pathsToSkip) {
-    // call _handlePathsToValidate here
-    // console.log(paths);
-    // console.log(options);
     // make a new variable that is paths intersection !options.pathsToSkip
-    // paths = _handlePathsToValidate(paths, newVar)
+    let valPaths = new Set(paths);
+    options.pathsToSkip.forEach((path) => {
+      if (valPaths.has(path)) {
+        valPaths.delete(path);
+      }
+    });
+    paths = _handlePathsToValidate(paths,valPaths);
   }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);

From bd619d88936e19aa6bdf04cf3d21e3d8ff9529b1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 20 May 2021 11:36:13 -0400
Subject: [PATCH 2060/2348] attempt to force a test suite run

---
 lib/document.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/document.js b/lib/document.js
index 13161bbae7f..4bcfcb912d8 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2470,6 +2470,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
         valPaths.delete(path);
       }
     });
+    // then send that to be validated
     paths = _handlePathsToValidate(paths,valPaths);
   }
   if (Array.isArray(pathsToValidate)) {

From aa0cbdd73642e21831e55fd40a0b77ec30d77c3f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 May 2021 12:55:27 -0400
Subject: [PATCH 2061/2348] fix(index.d.ts): allow using `type: [String]` with
 `string[]` when using SchemaDefinition with generic

Fix #10261
---
 index.d.ts                |  4 ++++
 test/typescript/schema.ts | 15 ++++++++++++++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 0441ff862dc..992dbef957d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1420,6 +1420,10 @@ declare module 'mongoose' {
       T extends string | number | boolean | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema ? T :
       T extends object[] ? Schema<Document<Unpacked<T>>>[] :
+      T extends string[] ? SchemaDefinitionWithBuiltInClass<string>[] :
+      T extends number[] ? SchemaDefinitionWithBuiltInClass<number>[] :
+      T extends boolean[] ? SchemaDefinitionWithBuiltInClass<boolean>[] :
+      T extends Function[] ? SchemaDefinitionWithBuiltInClass<Function>[] :
       T | typeof SchemaType | Schema;
 
     /** Defines a virtual with the given name that gets/sets this path. */
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index c1e5404d56e..fe8509164dd 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -1,4 +1,4 @@
-import { Schema, Document, SchemaDefinition, SchemaDefinitionProperty, Model } from 'mongoose';
+import { Schema, Document, SchemaDefinition, Model, DocumentDefinition } from 'mongoose';
 
 enum Genre {
   Action,
@@ -101,3 +101,16 @@ async function gh9857() {
 
   const schema = new Schema<UserDocument, UserModel, User>(schemaDefinition);
 }
+
+function gh10261() {
+  interface ValuesEntity {
+    values: string[];
+  }
+
+  const colorEntitySchemaDefinition: SchemaDefinition<DocumentDefinition<ValuesEntity>> = {
+    values: {
+      type: [String],
+      required: true
+    }
+  };
+}

From 4398aaa74dcd48f00e99710344967c5e008d87f5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 May 2021 13:22:35 -0400
Subject: [PATCH 2062/2348] fix(index.d.ts): support ReadonlyArray as well as
 regular array where possible in schema definitions

Fix #10260
---
 index.d.ts                | 25 ++++++++++++++-----------
 test/typescript/schema.ts |  3 ++-
 2 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 992dbef957d..8bb4022cfd8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1242,10 +1242,13 @@ declare module 'mongoose' {
     typeof SchemaType |
     Schema<any> |
     Schema<any>[] |
+    ReadonlyArray<Schema<any>> |
     SchemaTypeOptions<T extends undefined ? any : T>[] |
+    ReadonlyArray<SchemaTypeOptions<T extends undefined ? any : T>> |
     Function[] |
     SchemaDefinition<T> |
-    SchemaDefinition<T>[];
+    SchemaDefinition<T>[] |
+    ReadonlyArray<SchemaDefinition<T>>;
 
   type SchemaDefinition<T = undefined> = T extends undefined
     ? { [path: string]: SchemaDefinitionProperty; }
@@ -1419,11 +1422,11 @@ declare module 'mongoose' {
     type?:
       T extends string | number | boolean | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema ? T :
-      T extends object[] ? Schema<Document<Unpacked<T>>>[] :
-      T extends string[] ? SchemaDefinitionWithBuiltInClass<string>[] :
-      T extends number[] ? SchemaDefinitionWithBuiltInClass<number>[] :
-      T extends boolean[] ? SchemaDefinitionWithBuiltInClass<boolean>[] :
-      T extends Function[] ? SchemaDefinitionWithBuiltInClass<Function>[] :
+      T extends object[] ? (Schema<Document<Unpacked<T>>>[] | ReadonlyArray<Schema<Document<Unpacked<T>>>>) :
+      T extends string[] ? (SchemaDefinitionWithBuiltInClass<string>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<string>>) :
+      T extends number[] ? (SchemaDefinitionWithBuiltInClass<number>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<number>>) :
+      T extends boolean[] ? (SchemaDefinitionWithBuiltInClass<boolean>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<boolean>>) :
+      T extends Function[] ? (SchemaDefinitionWithBuiltInClass<Function>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<Function>>) :
       T | typeof SchemaType | Schema;
 
     /** Defines a virtual with the given name that gets/sets this path. */
@@ -1505,16 +1508,16 @@ declare module 'mongoose' {
     set?: (value: T, schematype?: this) => any;
 
     /** array of allowed values for this path. Allowed for strings, numbers, and arrays of strings */
-    enum?: Array<string | number | null> | { [path: string]: string | number | null };
+    enum?: Array<string | number | null> | ReadonlyArray<string | number | null> | { [path: string]: string | number | null };
 
     /** The default [subtype](http://bsonspec.org/spec.html) associated with this buffer when it is stored in MongoDB. Only allowed for buffer paths */
     subtype?: number
 
     /** The minimum value allowed for this path. Only allowed for numbers and dates. */
-    min?: number | Date | [number, string] | [Date, string];
+    min?: number | Date | [number, string] | [Date, string] | readonly [number, string] | readonly [Date, string];
 
     /** The maximum value allowed for this path. Only allowed for numbers and dates. */
-    max?: number | Date | [number, string] | [Date, string];
+    max?: number | Date | [number, string] | [Date, string] | readonly [number, string] | readonly [Date, string];
 
     /** Defines a TTL index on this path. Only allowed for dates. */
     expires?: number | Date;
@@ -1545,10 +1548,10 @@ declare module 'mongoose' {
     uppercase?: boolean;
 
     /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at least the given number. */
-    minlength?: number | [number, string];
+    minlength?: number | [number, string] | readonly [number, string];
 
     /** If set, Mongoose will add a custom validator that ensures the given string's `length` is at most the given number. */
-    maxlength?: number | [number, string];
+    maxlength?: number | [number, string] | readonly [number, string];
 
     [other: string]: any;
   }
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index fe8509164dd..a57d229d543 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -107,9 +107,10 @@ function gh10261() {
     values: string[];
   }
 
+  const type: ReadonlyArray<typeof String> = [String];
   const colorEntitySchemaDefinition: SchemaDefinition<DocumentDefinition<ValuesEntity>> = {
     values: {
-      type: [String],
+      type: type,
       required: true
     }
   };

From bdcd9e03bc57b3fdedaf9f2d552a1dcddffa33dd Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 20 May 2021 15:39:54 -0400
Subject: [PATCH 2063/2348] Update document.js

---
 lib/document.js | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4bcfcb912d8..4caf360e4e6 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2406,9 +2406,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       (typeof options === 'object') &&
       ('validateModifiedOnly' in options);
 
-  const pathsToSkip = options &&
-      (typeof options === 'object') &&
-      ('pathsToSkip' in options);
+  const pathsToSkip = get(options,'pathsToSkip', null);
 
   let shouldValidateModifiedOnly;
   if (hasValidateModifiedOnlyOption) {
@@ -2464,14 +2462,14 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   }
   if (pathsToSkip) {
     // make a new variable that is paths intersection !options.pathsToSkip
-    let valPaths = new Set(paths);
-    options.pathsToSkip.forEach((path) => {
-      if (valPaths.has(path)) {
+    const valPaths = new Set(paths);
+    for(const path of pathsToSkip) {
+      if(valPaths.has(path)) {
         valPaths.delete(path);
       }
-    });
+    }
     // then send that to be validated
-    paths = _handlePathsToValidate(paths,valPaths);
+    paths = _handlePathsToValidate(paths, valPaths);
   }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);

From 505e518fd25ecd6dda436779250de96ce057361d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 20 May 2021 15:50:15 -0400
Subject: [PATCH 2064/2348] linter fix

---
 lib/document.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 4caf360e4e6..6618bd848a0 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2406,7 +2406,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       (typeof options === 'object') &&
       ('validateModifiedOnly' in options);
 
-  const pathsToSkip = get(options,'pathsToSkip', null);
+  const pathsToSkip = get(options, 'pathsToSkip', null);
 
   let shouldValidateModifiedOnly;
   if (hasValidateModifiedOnlyOption) {
@@ -2463,8 +2463,8 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   if (pathsToSkip) {
     // make a new variable that is paths intersection !options.pathsToSkip
     const valPaths = new Set(paths);
-    for(const path of pathsToSkip) {
-      if(valPaths.has(path)) {
+    for (const path of pathsToSkip) {
+      if (valPaths.has(path)) {
         valPaths.delete(path);
       }
     }

From 7575aa6d0e856b858a03fdb0af28718df46672cd Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 20 May 2021 21:40:28 -0400
Subject: [PATCH 2065/2348] docs: migrate more pug tutorials to markdown re:
 #10271

---
 docs/documents.md    | 164 +++++++++
 docs/documents.pug   | 186 ----------
 docs/middleware.md   | 503 ++++++++++++++++++++++++++
 docs/middleware.pug  | 525 ---------------------------
 docs/migration.md    |  41 +++
 docs/migration.pug   |  54 ---
 docs/models.md       | 163 +++++++++
 docs/models.pug      | 191 ----------
 docs/plugins.md      | 116 ++++++
 docs/plugins.pug     | 138 -------
 docs/populate.md     | 816 +++++++++++++++++++++++++++++++++++++++++
 docs/populate.pug    | 838 -------------------------------------------
 docs/queries.md      | 245 +++++++++++++
 docs/queries.pug     | 267 --------------
 docs/source/index.js |  16 +-
 docs/subdocs.md      | 392 ++++++++++++++++++++
 docs/subdocs.pug     | 408 ---------------------
 17 files changed, 2448 insertions(+), 2615 deletions(-)
 create mode 100644 docs/documents.md
 delete mode 100644 docs/documents.pug
 create mode 100644 docs/middleware.md
 delete mode 100644 docs/middleware.pug
 create mode 100644 docs/migration.md
 delete mode 100644 docs/migration.pug
 create mode 100644 docs/models.md
 delete mode 100644 docs/models.pug
 create mode 100644 docs/plugins.md
 delete mode 100644 docs/plugins.pug
 create mode 100644 docs/populate.md
 delete mode 100644 docs/populate.pug
 create mode 100644 docs/queries.md
 delete mode 100644 docs/queries.pug
 create mode 100644 docs/subdocs.md
 delete mode 100644 docs/subdocs.pug

diff --git a/docs/documents.md b/docs/documents.md
new file mode 100644
index 00000000000..5c762adc7f9
--- /dev/null
+++ b/docs/documents.md
@@ -0,0 +1,164 @@
+## Documents
+
+Mongoose [documents](./api/document.html) represent a one-to-one mapping
+to documents as stored in MongoDB. Each document is an instance of its
+[Model](./models.html).
+
+<ul class="toc">
+  <li><a href="#documents-vs-models">Documents vs Models</a></li>
+  <li><a href="#retrieving">Retrieving</a></li>
+  <li><a href="#updating-using-save">Updating Using `save()`</a></li>
+  <li><a href="#updating-using-queries">Updating Using Queries</a></li>
+  <li><a href="#validating">Validating</a></li>
+  <li><a href="#overwriting">Overwriting</a></li>
+</ul>
+
+<h2 id="documents-vs-models"><a href="#documents-vs-models">Documents vs Models</a></h2>
+
+[Document](api.html#Document) and [Model](api.html#Model) are distinct
+classes in Mongoose. The Model class is a subclass of the Document class.
+When you use the [Model constructor](api.html#Model), you create a
+new document.
+
+```javascript
+const MyModel = mongoose.model('Test', new Schema({ name: String }));
+const doc = new MyModel();
+
+doc instanceof MyModel; // true
+doc instanceof mongoose.Model; // true
+doc instanceof mongoose.Document; // true
+```
+
+In Mongoose, a "document" generally means an instance of a model.
+You should not have to create an instance of the Document class without
+going through a model.
+
+<h2 id="retrieving"><a href="#retrieving">Retrieving</a></h2>
+
+When you load documents from MongoDB using model functions like [`findOne()`](api.html#model_Model.findOne),
+you get a Mongoose document back.
+
+```javascript
+const doc = await MyModel.findOne();
+
+doc instanceof MyModel; // true
+doc instanceof mongoose.Model; // true
+doc instanceof mongoose.Document; // true
+```
+
+<h2 id="updating-using-save"><a href="#updating-using-save">Updating Using <code>save()</code></a></h2>
+
+Mongoose documents track changes. You can modify a document using vanilla
+JavaScript assignments and Mongoose will convert it into [MongoDB update operators](https://docs.mongodb.com/manual/reference/operator/update/).
+
+```javascript
+doc.name = 'foo';
+
+// Mongoose sends an `updateOne({ _id: doc._id }, { $set: { name: 'foo' } })`
+// to MongoDB.
+await doc.save();
+```
+
+The `save()` method returns a promise. If `save()` succeeds, the promise
+resolves to the document that was saved.
+
+```javascript
+doc.save().then(savedDoc => {
+  savedDoc === doc; // true
+});
+```
+
+If the document with the corresponding `_id` is not found, Mongoose will
+report a `DocumentNotFoundError`:
+
+```javascript
+const doc = await MyModel.findOne();
+
+// Delete the document so Mongoose won't be able to save changes
+await MyModel.deleteOne({ _id: doc._id });
+
+doc.name = 'foo';
+await doc.save(); // Throws DocumentNotFoundError
+```
+
+<h2 id="updating-using-queries"><a href="#updating-using-queries">Updating Using Queries</a></h2>
+
+The [`save()`](api.html#model_Model-save) function is generally the right
+way to update a document with Mongoose. With `save()`, you get full
+[validation](validation.html) and [middleware](middleware.html).
+
+For cases when `save()` isn't flexible enough, Mongoose lets you create
+your own [MongoDB updates](https://docs.mongodb.com/manual/reference/operator/update/)
+with casting, [middleware](middleware.html#notes), and [limited validation](validation.html#update-validators).
+
+```javascript
+// Update all documents in the `mymodels` collection
+await MyModel.updateMany({}, { $set: { name: 'foo' } });
+```
+
+_Note that `update()`, `updateMany()`, `findOneAndUpdate()`, etc. do *not*
+execute `save()` middleware. If you need save middleware and full validation,
+first query for the document and then `save()` it._
+
+<h2 id="validating"><a href="#validating">Validating</a></h2>
+
+Documents are casted and validated before they are saved. Mongoose first casts
+values to the specified type and then validates them. Internally, Mongoose
+calls the document's [`validate()` method](api.html#document_Document-validate)
+before saving.
+
+```javascript
+const schema = new Schema({ name: String, age: { type: Number, min: 0 } });
+const Person = mongoose.model('Person', schema);
+
+let p = new Person({ name: 'foo', age: 'bar' });
+// Cast to Number failed for value "bar" at path "age"
+await p.validate();
+
+let p2 = new Person({ name: 'foo', age: -1 });
+// Path `age` (-1) is less than minimum allowed value (0).
+await p2.validate();
+```
+
+Mongoose also supports limited validation on updates using the [`runValidators` option](validation.html#update-validators).
+Mongoose casts parameters to query functions like `findOne()`, `updateOne()`
+by default. However, Mongoose does _not_ run validation on query function
+parameters by default. You need to set `runValidators: true` for Mongoose
+to validate.
+
+```javascript
+// Cast to number failed for value "bar" at path "age"
+await Person.updateOne({}, { age: 'bar' });
+
+// Path `age` (-1) is less than minimum allowed value (0).
+await Person.updateOne({}, { age: -1 }, { runValidators: true });
+```
+
+Read the [validation](./validation.html) guide for more details.
+
+<h2 id="overwriting"><a href="#overwriting">Overwriting</a></h2>
+
+There are 2 different ways to overwrite a document (replacing all keys in the
+document). One way is to use the
+[`Document#overwrite()` function](/docs/api/document.html#document_Document-overwrite)
+followed by `save()`.
+
+```javascript
+const doc = await Person.findOne({ _id });
+
+// Sets `name` and unsets all other properties
+doc.overwrite({ name: 'Jean-Luc Picard' });
+await doc.save();
+```
+
+The other way is to use [`Model.replaceOne()`](/docs/api/model.html#model_Model.replaceOne).
+
+```javascript
+// Sets `name` and unsets all other properties
+await Person.replaceOne({ _id }, { name: 'Jean-Luc Picard' });
+```
+
+### Next Up
+
+Now that we've covered Documents, let's take a look at
+[Subdocuments](/docs/subdocs.html).
\ No newline at end of file
diff --git a/docs/documents.pug b/docs/documents.pug
deleted file mode 100644
index 9ec93979979..00000000000
--- a/docs/documents.pug
+++ /dev/null
@@ -1,186 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Documents
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Mongoose [documents](./api/document.html) represent a one-to-one mapping
-    to documents as stored in MongoDB. Each document is an instance of its
-    [Model](./models.html).
-
-    <ul class="toc">
-      <li><a href="#documents-vs-models">Documents vs Models</a></li>
-      <li><a href="#retrieving">Retrieving</a></li>
-      <li><a href="#updating-using-save">Updating Using `save()`</a></li>
-      <li><a href="#updating-using-queries">Updating Using Queries</a></li>
-      <li><a href="#validating">Validating</a></li>
-      <li><a href="#overwriting">Overwriting</a></li>
-    </ul>
-
-    <h2 id="documents-vs-models"><a href="#documents-vs-models">Documents vs Models</a></h2>
-
-    [Document](api.html#Document) and [Model](api.html#Model) are distinct
-    classes in Mongoose. The Model class is a subclass of the Document class.
-    When you use the [Model constructor](api.html#Model), you create a
-    new document.
-
-    ```javascript
-    const MyModel = mongoose.model('Test', new Schema({ name: String }));
-    const doc = new MyModel();
-
-    doc instanceof MyModel; // true
-    doc instanceof mongoose.Model; // true
-    doc instanceof mongoose.Document; // true
-    ```
-
-    In Mongoose, a "document" generally means an instance of a model.
-    You should not have to create an instance of the Document class without
-    going through a model.
-
-    <h2 id="retrieving"><a href="#retrieving">Retrieving</a></h2>
-
-    When you load documents from MongoDB using model functions like [`findOne()`](api.html#model_Model.findOne),
-    you get a Mongoose document back.
-
-    ```javascript
-    const doc = await MyModel.findOne();
-
-    doc instanceof MyModel; // true
-    doc instanceof mongoose.Model; // true
-    doc instanceof mongoose.Document; // true
-    ```
-
-    <h2 id="updating-using-save"><a href="#updating-using-save">Updating Using <code>save()</code></a></h2>
-
-    Mongoose documents track changes. You can modify a document using vanilla
-    JavaScript assignments and Mongoose will convert it into [MongoDB update operators](https://docs.mongodb.com/manual/reference/operator/update/).
-
-    ```javascript
-    doc.name = 'foo';
-
-    // Mongoose sends an `updateOne({ _id: doc._id }, { $set: { name: 'foo' } })`
-    // to MongoDB.
-    await doc.save();
-    ```
-
-    The `save()` method returns a promise. If `save()` succeeds, the promise
-    resolves to the document that was saved.
-
-    ```javascript
-    doc.save().then(savedDoc => {
-      savedDoc === doc; // true
-    });
-    ```
-
-    If the document with the corresponding `_id` is not found, Mongoose will
-    report a `DocumentNotFoundError`:
-
-    ```javascript
-    const doc = await MyModel.findOne();
-
-    // Delete the document so Mongoose won't be able to save changes
-    await MyModel.deleteOne({ _id: doc._id });
-
-    doc.name = 'foo';
-    await doc.save(); // Throws DocumentNotFoundError
-    ```
-
-    <h2 id="updating-using-queries"><a href="#updating-using-queries">Updating Using Queries</a></h2>
-
-    The [`save()`](api.html#model_Model-save) function is generally the right
-    way to update a document with Mongoose. With `save()`, you get full
-    [validation](validation.html) and [middleware](middleware.html).
-
-    For cases when `save()` isn't flexible enough, Mongoose lets you create
-    your own [MongoDB updates](https://docs.mongodb.com/manual/reference/operator/update/)
-    with casting, [middleware](middleware.html#notes), and [limited validation](validation.html#update-validators).
-
-    ```javascript
-    // Update all documents in the `mymodels` collection
-    await MyModel.updateMany({}, { $set: { name: 'foo' } });
-    ```
-
-    _Note that `update()`, `updateMany()`, `findOneAndUpdate()`, etc. do *not*
-    execute `save()` middleware. If you need save middleware and full validation,
-    first query for the document and then `save()` it._
-
-    <h2 id="validating"><a href="#validating">Validating</a></h2>
-
-    Documents are casted and validated before they are saved. Mongoose first casts
-    values to the specified type and then validates them. Internally, Mongoose
-    calls the document's [`validate()` method](api.html#document_Document-validate)
-    before saving.
-
-    ```javascript
-    const schema = new Schema({ name: String, age: { type: Number, min: 0 } });
-    const Person = mongoose.model('Person', schema);
-
-    let p = new Person({ name: 'foo', age: 'bar' });
-    // Cast to Number failed for value "bar" at path "age"
-    await p.validate();
-
-    let p2 = new Person({ name: 'foo', age: -1 });
-    // Path `age` (-1) is less than minimum allowed value (0).
-    await p2.validate();
-    ```
-
-    Mongoose also supports limited validation on updates using the [`runValidators` option](validation.html#update-validators).
-    Mongoose casts parameters to query functions like `findOne()`, `updateOne()`
-    by default. However, Mongoose does _not_ run validation on query function
-    parameters by default. You need to set `runValidators: true` for Mongoose
-    to validate.
-
-    ```javascript
-    // Cast to number failed for value "bar" at path "age"
-    await Person.updateOne({}, { age: 'bar' });
-
-    // Path `age` (-1) is less than minimum allowed value (0).
-    await Person.updateOne({}, { age: -1 }, { runValidators: true });
-    ```
-
-    Read the [validation](./validation.html) guide for more details.
-
-    <h2 id="overwriting"><a href="#overwriting">Overwriting</a></h2>
-
-    There are 2 different ways to overwrite a document (replacing all keys in the
-    document). One way is to use the
-    [`Document#overwrite()` function](/docs/api/document.html#document_Document-overwrite)
-    followed by `save()`.
-
-    ```javascript
-    const doc = await Person.findOne({ _id });
-
-    // Sets `name` and unsets all other properties
-    doc.overwrite({ name: 'Jean-Luc Picard' });
-    await doc.save();
-    ```
-
-    The other way is to use [`Model.replaceOne()`](/docs/api/model.html#model_Model.replaceOne).
-
-    ```javascript
-    // Sets `name` and unsets all other properties
-    await Person.replaceOne({ _id }, { name: 'Jean-Luc Picard' });
-    ```
-
-    ### Next Up
-
-    Now that we've covered Documents, let's take a look at
-    [Subdocuments](/docs/subdocs.html).
diff --git a/docs/middleware.md b/docs/middleware.md
new file mode 100644
index 00000000000..be5bcec8075
--- /dev/null
+++ b/docs/middleware.md
@@ -0,0 +1,503 @@
+## Middleware
+
+Middleware (also called pre and post *hooks*) are functions which are passed
+control during execution of asynchronous functions. Middleware is specified
+on the schema level and is useful for writing [plugins](./plugins.html).
+
+<ul class="toc">
+  <li><a href="#types-of-middleware">Types of Middleware</a></li>
+  <li><a href="#pre">Pre</a></li>
+  <li><a href="#error-handling">Errors in Pre Hooks</a></li>
+  <li><a href="#post">Post</a></li>
+  <li><a href="#post-async">Asynchronous Post Hooks</a></li>
+  <li><a href="#defining">Define Middleware Before Compiling Models</a></li>
+  <li><a href="#order">Save/Validate Hooks</a></li>
+  <li><a href="#naming">Naming Conflicts</a></li>
+  <li><a href="#notes">Notes on findAndUpdate() and Query Middleware</a></li>
+  <li><a href="#error-handling-middleware">Error Handling Middleware</a></li>
+  <li><a href="#aggregate">Aggregation Hooks</a></li>
+  <li><a href="#synchronous">Synchronous Hooks</a></li>
+</ul>
+
+### Types of Middleware
+
+Mongoose has 4 types
+of middleware: document middleware, model middleware, aggregate middleware, and query middleware.
+Document middleware is supported for the following document functions.
+In document middleware functions, `this` refers to the document.
+
+* [validate](/docs/api/document.html#document_Document-validate)
+* [save](/docs/api/model.html#model_Model-save)
+* [remove](/docs/api/model.html#model_Model-remove)
+* [updateOne](/docs/api/document.html#document_Document-updateOne)
+* [deleteOne](/docs/api/model.html#model_Model-deleteOne)
+* [init](/docs/api/document.html#document_Document-init) (note: init hooks are [synchronous](#synchronous))
+
+Query middleware is supported for the following Model and Query functions.
+In query middleware functions, `this` refers to the query.
+
+* [count](./api.html#query_Query-count)
+* [deleteMany](./api.html#query_Query-deleteMany)
+* [deleteOne](./api.html#query_Query-deleteOne)
+* [find](./api.html#query_Query-find)
+* [findOne](./api.html#query_Query-findOne)
+* [findOneAndDelete](./api.html#query_Query-findOneAndDelete)
+* [findOneAndRemove](./api.html#query_Query-findOneAndRemove)
+* [findOneAndUpdate](./api.html#query_Query-findOneAndUpdate)
+* [remove](./api.html#model_Model.remove)
+* [update](./api.html#query_Query-update)
+* [updateOne](./api.html#query_Query-updateOne)
+* [updateMany](./api.html#query_Query-updateMany)
+
+Aggregate middleware is for `MyModel.aggregate()`. Aggregate middleware
+executes when you call `exec()` on an aggregate object.
+In aggregate middleware, `this` refers to the [aggregation object](./api.html#model_Model.aggregate).
+
+* [aggregate](./api.html#model_Model.aggregate)
+
+Model middleware is supported for the following model functions.
+In model middleware functions, `this` refers to the model.
+
+* [insertMany](./api.html#model_Model.insertMany)
+
+All middleware types support pre and post hooks.
+How pre and post hooks work is described in more detail below.
+
+**Note:** If you specify `schema.pre('remove')`, Mongoose will register this
+middleware for [`doc.remove()`](./api.html#model_Model-remove) by default. If you
+want to your middleware to run on [`Query.remove()`](./api.html#query_Query-remove)
+use [`schema.pre('remove', { query: true, document: false }, fn)`](./api.html#schema_Schema-pre).
+
+**Note:** Unlike `schema.pre('remove')`, Mongoose registers `updateOne` and
+`deleteOne` middleware on `Query#updateOne()` and `Query#deleteOne()` by default.
+This means that both `doc.updateOne()` and `Model.updateOne()` trigger
+`updateOne` hooks, but `this` refers to a query, not a document. To register
+`updateOne` or `deleteOne` middleware as document middleware, use
+`schema.pre('updateOne', { document: true, query: false })`.
+
+**Note:** The [`create()`](./api.html#model_Model.create) function fires `save()` hooks.
+
+<h3 id="pre"><a href="#pre">Pre</a></h3>
+
+Pre middleware functions are executed one after another, when each
+middleware calls `next`.
+
+```javascript
+const schema = new Schema(..);
+schema.pre('save', function(next) {
+  // do stuff
+  next();
+});
+```
+
+In [mongoose 5.x](http://thecodebarbarian.com/introducing-mongoose-5.html#promises-and-async-await-with-middleware), instead of calling `next()` manually, you can use a
+function that returns a promise. In particular, you can use [`async/await`](http://thecodebarbarian.com/common-async-await-design-patterns-in-node.js.html).
+
+```javascript
+schema.pre('save', function() {
+  return doStuff().
+    then(() => doMoreStuff());
+});
+
+// Or, in Node.js >= 7.6.0:
+schema.pre('save', async function() {
+  await doStuff();
+  await doMoreStuff();
+});
+```
+
+If you use `next()`, the `next()` call does **not** stop the rest of the code in your middleware function from executing. Use
+[the early `return` pattern](https://www.bennadel.com/blog/2323-use-a-return-statement-when-invoking-callbacks-especially-in-a-guard-statement.htm)
+to prevent the rest of your middleware function from running when you call `next()`.
+
+```javascript
+const schema = new Schema(..);
+schema.pre('save', function(next) {
+  if (foo()) {
+    console.log('calling next!');
+    // `return next();` will make sure the rest of this function doesn't run
+    /*return*/ next();
+  }
+  // Unless you comment out the `return` above, 'after next' will print
+  console.log('after next');
+});
+```
+
+<h4 id="use-cases">Use Cases</h4>
+
+Middleware are useful for atomizing model logic. Here are some other ideas:
+
+* complex validation
+* removing dependent documents (removing a user removes all their blogposts)
+* asynchronous defaults
+* asynchronous tasks that a certain action triggers
+
+<h4 id="error-handling">Errors in Pre Hooks</h4>
+
+If any pre hook errors out, mongoose will not execute subsequent middleware
+or the hooked function. Mongoose will instead pass an error to the callback
+and/or reject the returned promise. There are several ways to report an
+error in middleware:
+
+```javascript
+schema.pre('save', function(next) {
+  const err = new Error('something went wrong');
+  // If you call `next()` with an argument, that argument is assumed to be
+  // an error.
+  next(err);
+});
+
+schema.pre('save', function() {
+  // You can also return a promise that rejects
+  return new Promise((resolve, reject) => {
+    reject(new Error('something went wrong'));
+  });
+});
+
+schema.pre('save', function() {
+  // You can also throw a synchronous error
+  throw new Error('something went wrong');
+});
+
+schema.pre('save', async function() {
+  await Promise.resolve();
+  // You can also throw an error in an `async` function
+  throw new Error('something went wrong');
+});
+
+// later...
+
+// Changes will not be persisted to MongoDB because a pre hook errored out
+myDoc.save(function(err) {
+  console.log(err.message); // something went wrong
+});
+```
+
+Calling `next()` multiple times is a no-op. If you call `next()` with an
+error `err1` and then throw an error `err2`, mongoose will report `err1`.
+
+<h3 id="post"><a href="#post">Post middleware</a></h3>
+
+[post](/docs/api.html#schema_Schema-post) middleware are executed _after_
+the hooked method and all of its `pre` middleware have completed.
+
+```javascript
+schema.post('init', function(doc) {
+  console.log('%s has been initialized from the db', doc._id);
+});
+schema.post('validate', function(doc) {
+  console.log('%s has been validated (but not saved yet)', doc._id);
+});
+schema.post('save', function(doc) {
+  console.log('%s has been saved', doc._id);
+});
+schema.post('remove', function(doc) {
+  console.log('%s has been removed', doc._id);
+});
+```
+
+<h3 id="post-async"><a href="#post-async">Asynchronous Post Hooks</a></h3>
+
+If your post hook function takes at least 2 parameters, mongoose will
+assume the second parameter is a `next()` function that you will call to
+trigger the next middleware in the sequence.
+
+```javascript
+// Takes 2 parameters: this is an asynchronous post hook
+schema.post('save', function(doc, next) {
+  setTimeout(function() {
+    console.log('post1');
+    // Kick off the second post hook
+    next();
+  }, 10);
+});
+
+// Will not execute until the first middleware calls `next()`
+schema.post('save', function(doc, next) {
+  console.log('post2');
+  next();
+});
+```
+
+<h3 id="defining"><a href="#defining">Define Middleware Before Compiling Models</a></h3>
+
+Calling `pre()` or `post()` after [compiling a model](/docs/models.html#compiling)
+does **not** work in Mongoose in general. For example, the below `pre('save')`
+middleware will not fire.
+
+```javascript
+const schema = new mongoose.Schema({ name: String });
+
+// Compile a model from the schema
+const User = mongoose.model('User', schema);
+
+// Mongoose will **not** call the middleware function, because
+// this middleware was defined after the model was compiled
+schema.pre('save', () => console.log('Hello from pre save'));
+
+new User({ name: 'test' }).save();
+```
+
+This means that you must add all middleware and [plugins](/docs/plugins.html)
+**before** calling [`mongoose.model()`](/docs/api/mongoose.html#mongoose_Mongoose-model).
+The below script will print out "Hello from pre save":
+
+```javascript
+const schema = new mongoose.Schema({ name: String });
+// Mongoose will call this middleware function, because this script adds
+// the middleware to the schema before compiling the model.
+schema.pre('save', () => console.log('Hello from pre save'));
+
+// Compile a model from the schema
+const User = mongoose.model('User', schema);
+
+new User({ name: 'test' }).save();
+```
+
+As a consequence, be careful about exporting Mongoose models from the same
+file that you define your schema. If you choose to use this pattern, you
+must define [global plugins](/docs/api/mongoose.html#mongoose_Mongoose-plugin)
+**before** calling `require()` on your model file.
+
+```javascript
+const schema = new mongoose.Schema({ name: String });
+
+// Once you `require()` this file, you can no longer add any middleware
+// to this schema.
+module.exports = mongoose.model('User', schema);
+```
+
+<h3 id="order"><a href="#order">Save/Validate Hooks</a></h3>
+
+The `save()` function triggers `validate()` hooks, because mongoose
+has a built-in `pre('save')` hook that calls `validate()`. This means
+that all `pre('validate')` and `post('validate')` hooks get called
+**before** any `pre('save')` hooks.
+
+```javascript
+schema.pre('validate', function() {
+  console.log('this gets printed first');
+});
+schema.post('validate', function() {
+  console.log('this gets printed second');
+});
+schema.pre('save', function() {
+  console.log('this gets printed third');
+});
+schema.post('save', function() {
+  console.log('this gets printed fourth');
+});
+```
+
+<h3 id="naming"><a href="#naming">Naming Conflicts</a></h3>
+
+Mongoose has both query and document hooks for `remove()`.
+
+```javascript
+schema.pre('remove', function() { console.log('Removing!'); });
+
+// Prints "Removing!"
+doc.remove();
+
+// Does **not** print "Removing!". Query middleware for `remove` is not
+// executed by default.
+Model.remove();
+```
+
+You can pass options to [`Schema.pre()`](/docs/api.html#schema_Schema-pre)
+and [`Schema.post()`](/docs/api.html#schema_Schema-post) to switch whether
+Mongoose calls your `remove()` hook for [`Document.remove()`](/docs/api.html#model_Model-remove)
+or [`Model.remove()`](/docs/api.html#model_Model.remove). Note here that you need to set both `document` and `query` properties in the passed object:
+
+```javascript
+// Only document middleware
+schema.pre('remove', { document: true, query: false }, function() {
+  console.log('Removing doc!');
+});
+
+// Only query middleware. This will get called when you do `Model.remove()`
+// but not `doc.remove()`.
+schema.pre('remove', { query: true, document: false }, function() {
+  console.log('Removing!');
+});
+```
+
+<h3 id="notes"><a href="#notes">Notes on findAndUpdate() and Query Middleware</a></h3>
+
+Pre and post `save()` hooks are **not** executed on `update()`,
+`findOneAndUpdate()`, etc. You can see a more detailed discussion why in
+[this GitHub issue](http://github.com/Automattic/mongoose/issues/964).
+Mongoose 4.0 introduced distinct hooks for these functions.
+
+```javascript
+schema.pre('find', function() {
+  console.log(this instanceof mongoose.Query); // true
+  this.start = Date.now();
+});
+
+schema.post('find', function(result) {
+  console.log(this instanceof mongoose.Query); // true
+  // prints returned documents
+  console.log('find() returned ' + JSON.stringify(result));
+  // prints number of milliseconds the query took
+  console.log('find() took ' + (Date.now() - this.start) + ' millis');
+});
+```
+
+Query middleware differs from document middleware in a subtle but
+important way: in document middleware, `this` refers to the document
+being updated. In query middleware, mongoose doesn't necessarily have
+a reference to the document being updated, so `this` refers to the
+**query** object rather than the document being updated.
+
+For instance, if you wanted to add an `updatedAt` timestamp to every
+`updateOne()` call, you would use the following pre hook.
+
+```javascript
+schema.pre('updateOne', function() {
+  this.set({ updatedAt: new Date() });
+});
+```
+
+You **cannot** access the document being updated in `pre('updateOne')` or
+`pre('findOneAndUpdate')` query middleware. If you need to access the document
+that will be updated, you need to execute an explicit query for the document.
+
+```javascript
+schema.pre('findOneAndUpdate', async function() {
+  const docToUpdate = await this.model.findOne(this.getQuery());
+  console.log(docToUpdate); // The document that `findOneAndUpdate()` will modify
+});
+```
+
+However, if you define `pre('updateOne')` document middleware,
+`this` will be the document being updated. That's because `pre('updateOne')`
+document middleware hooks into [`Document#updateOne()`](/docs/api/document.html#document_Document-updateOne)
+rather than `Query#updateOne()`.
+
+```javascript
+schema.pre('updateOne', { document: true, query: false }, function() {
+  console.log('Updating');
+});
+const Model = mongoose.model('Test', schema);
+
+const doc = new Model();
+await doc.updateOne({ $set: { name: 'test' } }); // Prints "Updating"
+
+// Doesn't print "Updating", because `Query#updateOne()` doesn't fire
+// document middleware.
+await Model.updateOne({}, { $set: { name: 'test' } });
+```
+
+<h3 id="error-handling-middleware"><a href="#error-handling-middleware">Error Handling Middleware</a></h3>
+
+_New in 4.5.0_
+
+Middleware execution normally stops the first time a piece of middleware
+calls `next()` with an error. However, there is a special kind of post
+middleware called "error handling middleware" that executes specifically
+when an error occurs. Error handling middleware is useful for reporting
+errors and making error messages more readable.
+
+Error handling middleware is defined as middleware that takes one extra
+parameter: the 'error' that occurred as the first parameter to the function.
+Error handling middleware can then transform the error however you want.
+
+```javascript
+const schema = new Schema({
+  name: {
+    type: String,
+    // Will trigger a MongoError with code 11000 when
+    // you save a duplicate
+    unique: true
+  }
+});
+
+// Handler **must** take 3 parameters: the error that occurred, the document
+// in question, and the `next()` function
+schema.post('save', function(error, doc, next) {
+  if (error.name === 'MongoError' && error.code === 11000) {
+    next(new Error('There was a duplicate key error'));
+  } else {
+    next();
+  }
+});
+
+// Will trigger the `post('save')` error handler
+Person.create([{ name: 'Axl Rose' }, { name: 'Axl Rose' }]);
+```
+
+Error handling middleware also works with query middleware. You can
+also define a post `update()` hook that will catch MongoDB duplicate key
+errors.
+
+```javascript
+// The same E11000 error can occur when you call `update()`
+// This function **must** take 3 parameters. If you use the
+// `passRawResult` function, this function **must** take 4
+// parameters
+schema.post('update', function(error, res, next) {
+  if (error.name === 'MongoError' && error.code === 11000) {
+    next(new Error('There was a duplicate key error'));
+  } else {
+    next(); // The `update()` call will still error out.
+  }
+});
+
+const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
+Person.create(people, function(error) {
+  Person.update({ name: 'Slash' }, { $set: { name: 'Axl Rose' } }, function(error) {
+    // `error.message` will be "There was a duplicate key error"
+  });
+});
+```
+
+Error handling middleware can transform an error, but it can't remove the
+error. Even if you call `next()` with no error as shown above, the
+function call will still error out.
+
+<h3 id="aggregate"><a href="#aggregate">Aggregation Hooks</a></h3>
+
+You can also define hooks for the [`Model.aggregate()` function](api.html#model_Model.aggregate).
+In aggregation middleware functions, `this` refers to the [Mongoose `Aggregate` object](api.html#Aggregate).
+For example, suppose you're implementing soft deletes on a `Customer` model
+by adding an `isDeleted` property. To make sure `aggregate()` calls only look
+at customers that aren't soft deleted, you can use the below middleware to
+add a [`$match` stage](api.html#aggregate_Aggregate-match) to the beginning
+of each [aggregation pipeline](https://docs.mongodb.com/manual/core/aggregation-pipeline/).
+
+```javascript
+customerSchema.pre('aggregate', function() {
+  // Add a $match state to the beginning of each pipeline.
+  this.pipeline().unshift({ $match: { isDeleted: { $ne: true } } });
+});
+```
+
+The [`Aggregate#pipeline()` function](api.html#aggregate_Aggregate-pipeline)
+lets you access the MongoDB aggregation pipeline that Mongoose will send to
+the MongoDB server. It is useful for adding stages to the beginning of the
+pipeline from middleware.
+
+<h3 id="synchronous"><a href="#synchronous">Synchronous Hooks</a></h3>
+
+Certain Mongoose hooks are synchronous, which means they do **not** support
+functions that return promises or receive a `next()` callback. Currently,
+only `init` hooks are synchronous, because the [`init()` function](./api.html#document_Document-init)
+is synchronous. Below is an example of using pre and post init hooks.
+
+```javascript
+[require:post init hooks.*success]
+```
+
+To report an error in an init hook, you must throw a **synchronous** error.
+Unlike all other middleware, init middleware does **not** handle promise
+rejections.
+
+```javascript
+[require:post init hooks.*error]
+```
+
+<h3 id="next">Next Up</h3>
+
+Now that we've covered middleware, let's take a look at Mongoose's approach
+to faking JOINs with its query [population](/docs/populate.html) helper.
diff --git a/docs/middleware.pug b/docs/middleware.pug
deleted file mode 100644
index 862d7462a0b..00000000000
--- a/docs/middleware.pug
+++ /dev/null
@@ -1,525 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Middleware
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Middleware (also called pre and post *hooks*) are functions which are passed
-    control during execution of asynchronous functions. Middleware is specified
-    on the schema level and is useful for writing [plugins](./plugins.html).
-
-    <ul class="toc">
-      <li><a href="#types-of-middleware">Types of Middleware</a></li>
-      <li><a href="#pre">Pre</a></li>
-      <li><a href="#error-handling">Errors in Pre Hooks</a></li>
-      <li><a href="#post">Post</a></li>
-      <li><a href="#post-async">Asynchronous Post Hooks</a></li>
-      <li><a href="#defining">Define Middleware Before Compiling Models</a></li>
-      <li><a href="#order">Save/Validate Hooks</a></li>
-      <li><a href="#naming">Naming Conflicts</a></li>
-      <li><a href="#notes">Notes on findAndUpdate() and Query Middleware</a></li>
-      <li><a href="#error-handling-middleware">Error Handling Middleware</a></li>
-      <li><a href="#aggregate">Aggregation Hooks</a></li>
-      <li><a href="#synchronous">Synchronous Hooks</a></li>
-    </ul>
-
-    ### Types of Middleware
-
-    Mongoose has 4 types
-    of middleware: document middleware, model middleware, aggregate middleware, and query middleware.
-    Document middleware is supported for the following document functions.
-    In document middleware functions, `this` refers to the document.
-
-    * [validate](/docs/api/document.html#document_Document-validate)
-    * [save](/docs/api/model.html#model_Model-save)
-    * [remove](/docs/api/model.html#model_Model-remove)
-    * [updateOne](/docs/api/document.html#document_Document-updateOne)
-    * [deleteOne](/docs/api/model.html#model_Model-deleteOne)
-    * [init](/docs/api/document.html#document_Document-init) (note: init hooks are [synchronous](#synchronous))
-
-    Query middleware is supported for the following Model and Query functions.
-    In query middleware functions, `this` refers to the query.
-
-    * [count](./api.html#query_Query-count)
-    * [deleteMany](./api.html#query_Query-deleteMany)
-    * [deleteOne](./api.html#query_Query-deleteOne)
-    * [find](./api.html#query_Query-find)
-    * [findOne](./api.html#query_Query-findOne)
-    * [findOneAndDelete](./api.html#query_Query-findOneAndDelete)
-    * [findOneAndRemove](./api.html#query_Query-findOneAndRemove)
-    * [findOneAndUpdate](./api.html#query_Query-findOneAndUpdate)
-    * [remove](./api.html#model_Model.remove)
-    * [update](./api.html#query_Query-update)
-    * [updateOne](./api.html#query_Query-updateOne)
-    * [updateMany](./api.html#query_Query-updateMany)
-
-    Aggregate middleware is for `MyModel.aggregate()`. Aggregate middleware
-    executes when you call `exec()` on an aggregate object.
-    In aggregate middleware, `this` refers to the [aggregation object](./api.html#model_Model.aggregate).
-
-    * [aggregate](./api.html#model_Model.aggregate)
-
-    Model middleware is supported for the following model functions.
-    In model middleware functions, `this` refers to the model.
-
-    * [insertMany](./api.html#model_Model.insertMany)
-
-    All middleware types support pre and post hooks.
-    How pre and post hooks work is described in more detail below.
-
-    **Note:** If you specify `schema.pre('remove')`, Mongoose will register this
-    middleware for [`doc.remove()`](./api.html#model_Model-remove) by default. If you
-    want to your middleware to run on [`Query.remove()`](./api.html#query_Query-remove)
-    use [`schema.pre('remove', { query: true, document: false }, fn)`](./api.html#schema_Schema-pre).
-
-    **Note:** Unlike `schema.pre('remove')`, Mongoose registers `updateOne` and
-    `deleteOne` middleware on `Query#updateOne()` and `Query#deleteOne()` by default.
-    This means that both `doc.updateOne()` and `Model.updateOne()` trigger
-    `updateOne` hooks, but `this` refers to a query, not a document. To register
-    `updateOne` or `deleteOne` middleware as document middleware, use
-    `schema.pre('updateOne', { document: true, query: false })`.
-
-    **Note:** The [`create()`](./api.html#model_Model.create) function fires `save()` hooks.
-
-    <h3 id="pre"><a href="#pre">Pre</a></h3>
-
-    Pre middleware functions are executed one after another, when each
-    middleware calls `next`.
-
-    ```javascript
-    const schema = new Schema(..);
-    schema.pre('save', function(next) {
-      // do stuff
-      next();
-    });
-    ```
-
-    In [mongoose 5.x](http://thecodebarbarian.com/introducing-mongoose-5.html#promises-and-async-await-with-middleware), instead of calling `next()` manually, you can use a
-    function that returns a promise. In particular, you can use [`async/await`](http://thecodebarbarian.com/common-async-await-design-patterns-in-node.js.html).
-
-    ```javascript
-    schema.pre('save', function() {
-      return doStuff().
-        then(() => doMoreStuff());
-    });
-
-    // Or, in Node.js >= 7.6.0:
-    schema.pre('save', async function() {
-      await doStuff();
-      await doMoreStuff();
-    });
-    ```
-
-    If you use `next()`, the `next()` call does **not** stop the rest of the code in your middleware function from executing. Use
-    [the early `return` pattern](https://www.bennadel.com/blog/2323-use-a-return-statement-when-invoking-callbacks-especially-in-a-guard-statement.htm)
-    to prevent the rest of your middleware function from running when you call `next()`.
-
-    ```javascript
-    const schema = new Schema(..);
-    schema.pre('save', function(next) {
-      if (foo()) {
-        console.log('calling next!');
-        // `return next();` will make sure the rest of this function doesn't run
-        /*return*/ next();
-      }
-      // Unless you comment out the `return` above, 'after next' will print
-      console.log('after next');
-    });
-    ```
-
-    <h4 id="use-cases">Use Cases</h4>
-
-    Middleware are useful for atomizing model logic. Here are some other ideas:
-
-    * complex validation
-    * removing dependent documents (removing a user removes all their blogposts)
-    * asynchronous defaults
-    * asynchronous tasks that a certain action triggers
-
-    <h4 id="error-handling">Errors in Pre Hooks</h4>
-
-    If any pre hook errors out, mongoose will not execute subsequent middleware
-    or the hooked function. Mongoose will instead pass an error to the callback
-    and/or reject the returned promise. There are several ways to report an
-    error in middleware:
-
-    ```javascript
-    schema.pre('save', function(next) {
-      const err = new Error('something went wrong');
-      // If you call `next()` with an argument, that argument is assumed to be
-      // an error.
-      next(err);
-    });
-
-    schema.pre('save', function() {
-      // You can also return a promise that rejects
-      return new Promise((resolve, reject) => {
-        reject(new Error('something went wrong'));
-      });
-    });
-
-    schema.pre('save', function() {
-      // You can also throw a synchronous error
-      throw new Error('something went wrong');
-    });
-
-    schema.pre('save', async function() {
-      await Promise.resolve();
-      // You can also throw an error in an `async` function
-      throw new Error('something went wrong');
-    });
-
-    // later...
-
-    // Changes will not be persisted to MongoDB because a pre hook errored out
-    myDoc.save(function(err) {
-      console.log(err.message); // something went wrong
-    });
-    ```
-
-    Calling `next()` multiple times is a no-op. If you call `next()` with an
-    error `err1` and then throw an error `err2`, mongoose will report `err1`.
-
-    <h3 id="post"><a href="#post">Post middleware</a></h3>
-
-    [post](/docs/api.html#schema_Schema-post) middleware are executed _after_
-    the hooked method and all of its `pre` middleware have completed.
-
-    ```javascript
-    schema.post('init', function(doc) {
-      console.log('%s has been initialized from the db', doc._id);
-    });
-    schema.post('validate', function(doc) {
-      console.log('%s has been validated (but not saved yet)', doc._id);
-    });
-    schema.post('save', function(doc) {
-      console.log('%s has been saved', doc._id);
-    });
-    schema.post('remove', function(doc) {
-      console.log('%s has been removed', doc._id);
-    });
-    ```
-
-    <h3 id="post-async"><a href="#post-async">Asynchronous Post Hooks</a></h3>
-
-    If your post hook function takes at least 2 parameters, mongoose will
-    assume the second parameter is a `next()` function that you will call to
-    trigger the next middleware in the sequence.
-
-    ```javascript
-    // Takes 2 parameters: this is an asynchronous post hook
-    schema.post('save', function(doc, next) {
-      setTimeout(function() {
-        console.log('post1');
-        // Kick off the second post hook
-        next();
-      }, 10);
-    });
-
-    // Will not execute until the first middleware calls `next()`
-    schema.post('save', function(doc, next) {
-      console.log('post2');
-      next();
-    });
-    ```
-
-    <h3 id="defining"><a href="#defining">Define Middleware Before Compiling Models</a></h3>
-
-    Calling `pre()` or `post()` after [compiling a model](/docs/models.html#compiling)
-    does **not** work in Mongoose in general. For example, the below `pre('save')`
-    middleware will not fire.
-
-    ```javascript
-    const schema = new mongoose.Schema({ name: String });
-
-    // Compile a model from the schema
-    const User = mongoose.model('User', schema);
-
-    // Mongoose will **not** call the middleware function, because
-    // this middleware was defined after the model was compiled
-    schema.pre('save', () => console.log('Hello from pre save'));
-
-    new User({ name: 'test' }).save();
-    ```
-
-    This means that you must add all middleware and [plugins](/docs/plugins.html)
-    **before** calling [`mongoose.model()`](/docs/api/mongoose.html#mongoose_Mongoose-model).
-    The below script will print out "Hello from pre save":
-
-    ```javascript
-    const schema = new mongoose.Schema({ name: String });
-    // Mongoose will call this middleware function, because this script adds
-    // the middleware to the schema before compiling the model.
-    schema.pre('save', () => console.log('Hello from pre save'));
-
-    // Compile a model from the schema
-    const User = mongoose.model('User', schema);
-
-    new User({ name: 'test' }).save();
-    ```
-
-    As a consequence, be careful about exporting Mongoose models from the same
-    file that you define your schema. If you choose to use this pattern, you
-    must define [global plugins](/docs/api/mongoose.html#mongoose_Mongoose-plugin)
-    **before** calling `require()` on your model file.
-
-    ```javascript
-    const schema = new mongoose.Schema({ name: String });
-
-    // Once you `require()` this file, you can no longer add any middleware
-    // to this schema.
-    module.exports = mongoose.model('User', schema);
-    ```
-
-    <h3 id="order"><a href="#order">Save/Validate Hooks</a></h3>
-
-    The `save()` function triggers `validate()` hooks, because mongoose
-    has a built-in `pre('save')` hook that calls `validate()`. This means
-    that all `pre('validate')` and `post('validate')` hooks get called
-    **before** any `pre('save')` hooks.
-
-    ```javascript
-    schema.pre('validate', function() {
-      console.log('this gets printed first');
-    });
-    schema.post('validate', function() {
-      console.log('this gets printed second');
-    });
-    schema.pre('save', function() {
-      console.log('this gets printed third');
-    });
-    schema.post('save', function() {
-      console.log('this gets printed fourth');
-    });
-    ```
-
-    <h3 id="naming"><a href="#naming">Naming Conflicts</a></h3>
-
-    Mongoose has both query and document hooks for `remove()`.
-
-    ```javascript
-    schema.pre('remove', function() { console.log('Removing!'); });
-
-    // Prints "Removing!"
-    doc.remove();
-
-    // Does **not** print "Removing!". Query middleware for `remove` is not
-    // executed by default.
-    Model.remove();
-    ```
-
-    You can pass options to [`Schema.pre()`](/docs/api.html#schema_Schema-pre)
-    and [`Schema.post()`](/docs/api.html#schema_Schema-post) to switch whether
-    Mongoose calls your `remove()` hook for [`Document.remove()`](/docs/api.html#model_Model-remove)
-    or [`Model.remove()`](/docs/api.html#model_Model.remove). Note here that you need to set both `document` and `query` properties in the passed object:
-
-    ```javascript
-    // Only document middleware
-    schema.pre('remove', { document: true, query: false }, function() {
-      console.log('Removing doc!');
-    });
-
-    // Only query middleware. This will get called when you do `Model.remove()`
-    // but not `doc.remove()`.
-    schema.pre('remove', { query: true, document: false }, function() {
-      console.log('Removing!');
-    });
-    ```
-
-    <h3 id="notes"><a href="#notes">Notes on findAndUpdate() and Query Middleware</a></h3>
-
-    Pre and post `save()` hooks are **not** executed on `update()`,
-    `findOneAndUpdate()`, etc. You can see a more detailed discussion why in
-    [this GitHub issue](http://github.com/Automattic/mongoose/issues/964).
-    Mongoose 4.0 introduced distinct hooks for these functions.
-
-    ```javascript
-    schema.pre('find', function() {
-      console.log(this instanceof mongoose.Query); // true
-      this.start = Date.now();
-    });
-
-    schema.post('find', function(result) {
-      console.log(this instanceof mongoose.Query); // true
-      // prints returned documents
-      console.log('find() returned ' + JSON.stringify(result));
-      // prints number of milliseconds the query took
-      console.log('find() took ' + (Date.now() - this.start) + ' millis');
-    });
-    ```
-
-    Query middleware differs from document middleware in a subtle but
-    important way: in document middleware, `this` refers to the document
-    being updated. In query middleware, mongoose doesn't necessarily have
-    a reference to the document being updated, so `this` refers to the
-    **query** object rather than the document being updated.
-
-    For instance, if you wanted to add an `updatedAt` timestamp to every
-    `updateOne()` call, you would use the following pre hook.
-
-    ```javascript
-    schema.pre('updateOne', function() {
-      this.set({ updatedAt: new Date() });
-    });
-    ```
-
-    You **cannot** access the document being updated in `pre('updateOne')` or
-    `pre('findOneAndUpdate')` query middleware. If you need to access the document
-    that will be updated, you need to execute an explicit query for the document.
-
-    ```javascript
-    schema.pre('findOneAndUpdate', async function() {
-      const docToUpdate = await this.model.findOne(this.getQuery());
-      console.log(docToUpdate); // The document that `findOneAndUpdate()` will modify
-    });
-    ```
-
-    However, if you define `pre('updateOne')` document middleware,
-    `this` will be the document being updated. That's because `pre('updateOne')`
-    document middleware hooks into [`Document#updateOne()`](/docs/api/document.html#document_Document-updateOne)
-    rather than `Query#updateOne()`.
-
-    ```javascript
-    schema.pre('updateOne', { document: true, query: false }, function() {
-      console.log('Updating');
-    });
-    const Model = mongoose.model('Test', schema);
-
-    const doc = new Model();
-    await doc.updateOne({ $set: { name: 'test' } }); // Prints "Updating"
-
-    // Doesn't print "Updating", because `Query#updateOne()` doesn't fire
-    // document middleware.
-    await Model.updateOne({}, { $set: { name: 'test' } });
-    ```
-
-    <h3 id="error-handling-middleware"><a href="#error-handling-middleware">Error Handling Middleware</a></h3>
-
-    _New in 4.5.0_
-
-    Middleware execution normally stops the first time a piece of middleware
-    calls `next()` with an error. However, there is a special kind of post
-    middleware called "error handling middleware" that executes specifically
-    when an error occurs. Error handling middleware is useful for reporting
-    errors and making error messages more readable.
-
-    Error handling middleware is defined as middleware that takes one extra
-    parameter: the 'error' that occurred as the first parameter to the function.
-    Error handling middleware can then transform the error however you want.
-
-    ```javascript
-    const schema = new Schema({
-      name: {
-        type: String,
-        // Will trigger a MongoError with code 11000 when
-        // you save a duplicate
-        unique: true
-      }
-    });
-
-    // Handler **must** take 3 parameters: the error that occurred, the document
-    // in question, and the `next()` function
-    schema.post('save', function(error, doc, next) {
-      if (error.name === 'MongoError' && error.code === 11000) {
-        next(new Error('There was a duplicate key error'));
-      } else {
-        next();
-      }
-    });
-
-    // Will trigger the `post('save')` error handler
-    Person.create([{ name: 'Axl Rose' }, { name: 'Axl Rose' }]);
-    ```
-
-    Error handling middleware also works with query middleware. You can
-    also define a post `update()` hook that will catch MongoDB duplicate key
-    errors.
-
-    ```javascript
-    // The same E11000 error can occur when you call `update()`
-    // This function **must** take 3 parameters. If you use the
-    // `passRawResult` function, this function **must** take 4
-    // parameters
-    schema.post('update', function(error, res, next) {
-      if (error.name === 'MongoError' && error.code === 11000) {
-        next(new Error('There was a duplicate key error'));
-      } else {
-        next(); // The `update()` call will still error out.
-      }
-    });
-
-    const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
-    Person.create(people, function(error) {
-      Person.update({ name: 'Slash' }, { $set: { name: 'Axl Rose' } }, function(error) {
-        // `error.message` will be "There was a duplicate key error"
-      });
-    });
-    ```
-
-    Error handling middleware can transform an error, but it can't remove the
-    error. Even if you call `next()` with no error as shown above, the
-    function call will still error out.
-
-    <h3 id="aggregate"><a href="#aggregate">Aggregation Hooks</a></h3>
-
-    You can also define hooks for the [`Model.aggregate()` function](api.html#model_Model.aggregate).
-    In aggregation middleware functions, `this` refers to the [Mongoose `Aggregate` object](api.html#Aggregate).
-    For example, suppose you're implementing soft deletes on a `Customer` model
-    by adding an `isDeleted` property. To make sure `aggregate()` calls only look
-    at customers that aren't soft deleted, you can use the below middleware to
-    add a [`$match` stage](api.html#aggregate_Aggregate-match) to the beginning
-    of each [aggregation pipeline](https://docs.mongodb.com/manual/core/aggregation-pipeline/).
-
-    ```javascript
-    customerSchema.pre('aggregate', function() {
-      // Add a $match state to the beginning of each pipeline.
-      this.pipeline().unshift({ $match: { isDeleted: { $ne: true } } });
-    });
-    ```
-
-    The [`Aggregate#pipeline()` function](api.html#aggregate_Aggregate-pipeline)
-    lets you access the MongoDB aggregation pipeline that Mongoose will send to
-    the MongoDB server. It is useful for adding stages to the beginning of the
-    pipeline from middleware.
-
-    <h3 id="synchronous"><a href="#synchronous">Synchronous Hooks</a></h3>
-
-    Certain Mongoose hooks are synchronous, which means they do **not** support
-    functions that return promises or receive a `next()` callback. Currently,
-    only `init` hooks are synchronous, because the [`init()` function](./api.html#document_Document-init)
-    is synchronous. Below is an example of using pre and post init hooks.
-
-    ```javascript
-    [require:post init hooks.*success]
-    ```
-
-    To report an error in an init hook, you must throw a **synchronous** error.
-    Unlike all other middleware, init middleware does **not** handle promise
-    rejections.
-
-    ```javascript
-    [require:post init hooks.*error]
-    ```
-
-    <h3 id="next">Next Up</h3>
-
-    Now that we've covered middleware, let's take a look at Mongoose's approach
-    to faking JOINs with its query [population](/docs/populate.html) helper.
diff --git a/docs/migration.md b/docs/migration.md
new file mode 100644
index 00000000000..f4103f73d33
--- /dev/null
+++ b/docs/migration.md
@@ -0,0 +1,41 @@
+## Migrating from 3.x to 4.x
+
+There are several [backwards-breaking changes](https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes) to be aware of when migrating from Mongoose 3 to Mongoose 4.
+
+<h3 id="findandmodify-new">`findOneAndUpdate()` new field is now `false` by default</h3>
+
+Mongoose's `findOneAndUpdate()`, `findOneAndRemove()`,
+`findByIdAndUpdate()`, and `findByIdAndRemove()` functions are just
+wrappers around MongoDB's
+[`findAndModify` command](http://docs.mongodb.org/manual/reference/method/db.collection.findAndModify/).
+Both the MongoDB server and the MongoDB NodeJS driver set the `new` option
+to false by default, but mongoose 3 overwrote this default. In order to be
+more consistent with the MongoDB server's documentation, mongoose will
+use false by default. That is,
+`findOneAndUpdate({}, { $set: { test: 1 } }, callback);` will return the
+document as it was *before* the `$set` operation was applied.
+
+To return the document with modifications made on the update, use the `new: true` option.
+
+```javascript
+MyModel.findOneAndUpdate({}, { $set: { test: 1 } }, { new: true }, callback);
+```
+
+### CastError and ValidationError now use `kind` instead of `type` to report error types
+
+In Mongoose 3, CastError and ValidationError had a `type` field. For instance, user defined validation errors would have a `type` property that contained the string 'user defined'. In Mongoose 4, this property has been renamed to `kind` due to [the V8 JavaScript engine using the Error.type property internally](https://code.google.com/p/v8/issues/detail?id=2397).
+
+<h3 id="promises">Query now has a `.then()` function</h3>
+
+In mongoose 3, you needed to call `.exec()` on a query chain to get a
+promise back, like `MyModel.find().exec().then();`. Mongoose 4 queries are
+promises, so you can do `MyModel.find().then()` instead. Be careful if
+you're using functions like
+[q's `Q.ninvoke()`](https://github.com/kriskowal/q#adapting-node) or
+otherwise returning a mongoose query from a promise.
+
+<h3 id="moreinfo">More Info</h3>
+
+Related blog posts:
+
+- [Introducing Version 4.0 of the Mongoose NodeJS ODM](http://www.mongodb.com/blog/post/introducing-version-40-mongoose-nodejs-odm)
diff --git a/docs/migration.pug b/docs/migration.pug
deleted file mode 100644
index e60b227e808..00000000000
--- a/docs/migration.pug
+++ /dev/null
@@ -1,54 +0,0 @@
-extends layout
-
-block append style
-  style.
-    table td {
-      padding-right: 15px;
-    }
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  h2 Migrating from 3.x to 4.x
-  :markdown
-    There are several [backwards-breaking changes](https://github.com/Automattic/mongoose/wiki/4.0-Release-Notes) to be aware of when migrating from Mongoose 3 to Mongoose 4.
-
-    <h3 id="findandmodify-new">`findOneAndUpdate()` new field is now `false` by default</h3>
-
-    Mongoose's `findOneAndUpdate()`, `findOneAndRemove()`,
-    `findByIdAndUpdate()`, and `findByIdAndRemove()` functions are just
-    wrappers around MongoDB's
-    [`findAndModify` command](http://docs.mongodb.org/manual/reference/method/db.collection.findAndModify/).
-    Both the MongoDB server and the MongoDB NodeJS driver set the `new` option
-    to false by default, but mongoose 3 overwrote this default. In order to be
-    more consistent with the MongoDB server's documentation, mongoose will
-    use false by default. That is,
-    `findOneAndUpdate({}, { $set: { test: 1 } }, callback);` will return the
-    document as it was *before* the `$set` operation was applied.
-
-    To return the document with modifications made on the update, use the `new: true` option.
-
-    ```javascript
-    MyModel.findOneAndUpdate({}, { $set: { test: 1 } }, { new: true }, callback);
-    ```
-
-    ### CastError and ValidationError now use `kind` instead of `type` to report error types
-
-    In Mongoose 3, CastError and ValidationError had a `type` field. For instance, user defined validation errors would have a `type` property that contained the string 'user defined'. In Mongoose 4, this property has been renamed to `kind` due to [the V8 JavaScript engine using the Error.type property internally](https://code.google.com/p/v8/issues/detail?id=2397).
-
-    <h3 id="promises">Query now has a `.then()` function</h3>
-
-    In mongoose 3, you needed to call `.exec()` on a query chain to get a
-    promise back, like `MyModel.find().exec().then();`. Mongoose 4 queries are
-    promises, so you can do `MyModel.find().then()` instead. Be careful if
-    you're using functions like
-    [q's `Q.ninvoke()`](https://github.com/kriskowal/q#adapting-node) or
-    otherwise returning a mongoose query from a promise.
-
-    <h3 id="moreinfo">More Info</h3>
-
-    Related blog posts:
-
-    - [Introducing Version 4.0 of the Mongoose NodeJS ODM](http://www.mongodb.com/blog/post/introducing-version-40-mongoose-nodejs-odm)
diff --git a/docs/models.md b/docs/models.md
new file mode 100644
index 00000000000..476546f8fd0
--- /dev/null
+++ b/docs/models.md
@@ -0,0 +1,163 @@
+## Models
+
+[Models](./api.html#model-js) are fancy constructors compiled from
+`Schema` definitions. An instance of a model is called a
+[document](./documents.html). Models are responsible for creating and
+reading documents from the underlying MongoDB database.
+
+* [Compiling your first model](#compiling)
+* [Constructing Documents](#constructing-documents)
+* [Querying](#querying)
+* [Deleting](#deleting)
+* [Updating](#updating)
+* [Change Streams](#change-streams)
+
+<h3 id="compiling">Compiling your first model</h3>
+
+When you call `mongoose.model()` on a schema, Mongoose _compiles_ a model
+for you.
+
+```javascript
+const schema = new mongoose.Schema({ name: 'string', size: 'string' });
+const Tank = mongoose.model('Tank', schema);
+```
+
+The first argument is the _singular_ name of the collection your model is
+for. **Mongoose automatically looks for the plural, lowercased version of your model name.**
+Thus, for the example above, the model Tank is for the **tanks** collection
+in the database.
+
+**Note:** The `.model()` function makes a copy of `schema`. Make sure that
+you've added everything you want to `schema`, including hooks,
+before calling `.model()`!
+
+### Constructing Documents
+
+An instance of a model is called a [document](./documents.html). Creating
+them and saving to the database is easy.
+
+```javascript
+const Tank = mongoose.model('Tank', yourSchema);
+
+const small = new Tank({ size: 'small' });
+small.save(function (err) {
+  if (err) return handleError(err);
+  // saved!
+});
+
+// or
+
+Tank.create({ size: 'small' }, function (err, small) {
+  if (err) return handleError(err);
+  // saved!
+});
+
+// or, for inserting large batches of documents
+Tank.insertMany([{ size: 'small' }], function(err) {
+
+});
+```
+
+Note that no tanks will be created/removed until the connection your model
+uses is open. Every model has an associated connection. When you use
+`mongoose.model()`, your model will use the default mongoose connection.
+
+```javascript
+mongoose.connect('mongodb://localhost/gettingstarted', {useNewUrlParser: true});
+```
+
+If you create a custom connection, use that connection's `model()` function
+instead.
+```javascript
+const connection = mongoose.createConnection('mongodb://localhost:27017/test');
+const Tank = connection.model('Tank', yourSchema);
+```
+
+### Querying
+
+Finding documents is easy with Mongoose, which supports the [rich](http://www.mongodb.org/display/DOCS/Advanced+Queries) query syntax of MongoDB. Documents can be retreived using each `models` [find](./api.html#model_Model.find), [findById](./api.html#model_Model.findById), [findOne](./api.html#model_Model.findOne), or [where](./api.html#model_Model.where) static methods.
+
+```javascript
+Tank.find({ size: 'small' }).where('createdDate').gt(oneYearAgo).exec(callback);
+```
+
+See the chapter on [queries](./queries.html) for more details on how to use the [Query](./api.html#query-js) api.
+
+### Deleting
+
+Models have static `deleteOne()` and `deleteMany()` functions
+for removing all documents matching the given `filter`.
+
+```javascript
+Tank.deleteOne({ size: 'large' }, function (err) {
+  if (err) return handleError(err);
+  // deleted at most one tank document
+});
+```
+
+### Updating
+
+Each `model` has its own `update` method for modifying documents in the
+database without returning them to your application. See the
+[API](./api.html#model_Model.updateOne) docs for more detail.
+
+```javascript
+Tank.updateOne({ size: 'large' }, { name: 'T-90' }, function(err, res) {
+  // Updated at most one doc, `res.modifiedCount` contains the number
+  // of docs that MongoDB updated
+});
+```
+
+_If you want to update a single document in the db and return it to your
+application, use [findOneAndUpdate](./api.html#model_Model.findOneAndUpdate)
+instead._
+
+### Change Streams
+
+_New in MongoDB 3.6.0 and Mongoose 5.0.0_
+
+[Change streams](https://docs.mongodb.com/manual/changeStreams/) provide
+a way for you to listen to all inserts and updates going through your
+MongoDB database. Note that change streams do **not** work unless you're
+connected to a [MongoDB replica set](https://docs.mongodb.com/manual/replication/).
+
+```javascript
+async function run() {
+  // Create a new mongoose model
+  const personSchema = new mongoose.Schema({
+    name: String
+  });
+  const Person = mongoose.model('Person', personSchema, 'Person');
+
+  // Create a change stream. The 'change' event gets emitted when there's a
+  // change in the database
+  Person.watch().
+    on('change', data => console.log(new Date(), data));
+
+  // Insert a doc, will trigger the change stream handler above
+  console.log(new Date(), 'Inserting doc');
+  await Person.create({ name: 'Axl Rose' });
+}
+```
+
+The output from the above [async function](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html) will look like what you see below.
+
+```
+2018-05-11T15:05:35.467Z 'Inserting doc'
+2018-05-11T15:05:35.487Z 'Inserted doc'
+2018-05-11T15:05:35.491Z { _id: { _data: ... },
+  operationType: 'insert',
+  fullDocument: { _id: 5af5b13fe526027666c6bf83, name: 'Axl Rose', __v: 0 },
+  ns: { db: 'test', coll: 'Person' },
+  documentKey: { _id: 5af5b13fe526027666c6bf83 } }
+```
+
+You can read more about [change streams in mongoose in this blog post](http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-change-streams.html#change-streams-in-mongoose).
+
+### Yet more
+
+The [API docs](./api.html#model_Model) cover many additional methods available like [count](./api.html#model_Model.count), [mapReduce](./api.html#model_Model.mapReduce), [aggregate](./api.html#model_Model.aggregate), and [more](./api.html#model_Model.findOneAndRemove).
+
+### Next Up
+
+Now that we've covered `Models`, let's take a look at [Documents](/docs/documents.html).
\ No newline at end of file
diff --git a/docs/models.pug b/docs/models.pug
deleted file mode 100644
index 7c4b27ff2e0..00000000000
--- a/docs/models.pug
+++ /dev/null
@@ -1,191 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Models
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    [Models](./api.html#model-js) are fancy constructors compiled from
-    `Schema` definitions. An instance of a model is called a
-    [document](./documents.html). Models are responsible for creating and
-    reading documents from the underlying MongoDB database.
-
-  ul
-    li
-      a(href="#compiling") Compiling your first model
-    li
-      a(href="#constructing-documents") Constructing Documents
-    li
-      a(href="#querying") Querying
-    li
-      a(href="#deleting") Deleting
-    li
-      a(href="#updating") Updating
-    li
-      a(href="#change-streams") Change Streams
-
-  h3(id="compiling") Compiling your first model
-  :markdown
-    When you call `mongoose.model()` on a schema, Mongoose _compiles_ a model
-    for you.
-
-    ```javascript
-    const schema = new mongoose.Schema({ name: 'string', size: 'string' });
-    const Tank = mongoose.model('Tank', schema);
-    ```
-  :markdown
-    The first argument is the _singular_ name of the collection your model is
-    for. **Mongoose automatically looks for the plural, lowercased version of your model name.**
-    Thus, for the example above, the model Tank is for the **tanks** collection
-    in the database.
-
-    **Note:** The `.model()` function makes a copy of `schema`. Make sure that
-    you've added everything you want to `schema`, including hooks,
-    before calling `.model()`!
-
-  h3(id="constructing-documents") Constructing Documents
-  :markdown
-    An instance of a model is called a [document](./documents.html). Creating
-    them and saving to the database is easy.
-
-    ```javascript
-    const Tank = mongoose.model('Tank', yourSchema);
-
-    const small = new Tank({ size: 'small' });
-    small.save(function (err) {
-      if (err) return handleError(err);
-      // saved!
-    });
-
-    // or
-
-    Tank.create({ size: 'small' }, function (err, small) {
-      if (err) return handleError(err);
-      // saved!
-    });
-
-    // or, for inserting large batches of documents
-    Tank.insertMany([{ size: 'small' }], function(err) {
-
-    });
-    ```
-  :markdown
-    Note that no tanks will be created/removed until the connection your model
-    uses is open. Every model has an associated connection. When you use
-    `mongoose.model()`, your model will use the default mongoose connection.
-    ```javascript
-    mongoose.connect('mongodb://localhost/gettingstarted', {useNewUrlParser: true});
-    ```
-  :markdown
-    If you create a custom connection, use that connection's `model()` function
-    instead.
-    ```javascript
-    const connection = mongoose.createConnection('mongodb://localhost:27017/test');
-    const Tank = connection.model('Tank', yourSchema);
-    ```
-  h3(id="querying") Querying
-  :markdown
-    Finding documents is easy with Mongoose, which supports the [rich](http://www.mongodb.org/display/DOCS/Advanced+Queries) query syntax of MongoDB. Documents can be retreived using each `models` [find](./api.html#model_Model.find), [findById](./api.html#model_Model.findById), [findOne](./api.html#model_Model.findOne), or [where](./api.html#model_Model.where) static methods.
-
-    ```javascript
-    Tank.find({ size: 'small' }).where('createdDate').gt(oneYearAgo).exec(callback);
-    ```
-  :markdown
-    See the chapter on [queries](./queries.html) for more details on how to use the [Query](./api.html#query-js) api.
-
-  h3(id="deleting") Deleting
-  :markdown
-    Models have static `deleteOne()` and `deleteMany()` functions
-    for removing all documents matching the given `filter`.
-
-    ```javascript
-    Tank.deleteOne({ size: 'large' }, function (err) {
-      if (err) return handleError(err);
-      // deleted at most one tank document
-    });
-    ```
-
-  h3(id="updating") Updating
-  :markdown
-    Each `model` has its own `update` method for modifying documents in the
-    database without returning them to your application. See the
-    [API](./api.html#model_Model.updateOne) docs for more detail.
-
-    ```javascript
-    Tank.updateOne({ size: 'large' }, { name: 'T-90' }, function(err, res) {
-      // Updated at most one doc, `res.modifiedCount` contains the number
-      // of docs that MongoDB updated
-    });
-    ```
-
-    _If you want to update a single document in the db and return it to your
-    application, use [findOneAndUpdate](./api.html#model_Model.findOneAndUpdate)
-    instead._
-
-  h3(id="change-streams") Change Streams
-
-  :markdown
-    _New in MongoDB 3.6.0 and Mongoose 5.0.0_
-
-    [Change streams](https://docs.mongodb.com/manual/changeStreams/) provide
-    a way for you to listen to all inserts and updates going through your
-    MongoDB database. Note that change streams do **not** work unless you're
-    connected to a [MongoDB replica set](https://docs.mongodb.com/manual/replication/).
-
-    ```javascript
-    async function run() {
-      // Create a new mongoose model
-      const personSchema = new mongoose.Schema({
-        name: String
-      });
-      const Person = mongoose.model('Person', personSchema, 'Person');
-
-      // Create a change stream. The 'change' event gets emitted when there's a
-      // change in the database
-      Person.watch().
-        on('change', data => console.log(new Date(), data));
-
-      // Insert a doc, will trigger the change stream handler above
-      console.log(new Date(), 'Inserting doc');
-      await Person.create({ name: 'Axl Rose' });
-    }
-    ```
-
-    The output from the above [async function](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html) will look like what you see below.
-
-    ```
-    2018-05-11T15:05:35.467Z 'Inserting doc'
-    2018-05-11T15:05:35.487Z 'Inserted doc'
-    2018-05-11T15:05:35.491Z { _id: { _data: ... },
-      operationType: 'insert',
-      fullDocument: { _id: 5af5b13fe526027666c6bf83, name: 'Axl Rose', __v: 0 },
-      ns: { db: 'test', coll: 'Person' },
-      documentKey: { _id: 5af5b13fe526027666c6bf83 } }
-    ```
-
-    You can read more about [change streams in mongoose in this blog post](http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-36-change-streams.html#change-streams-in-mongoose).
-
-  h3 Yet more
-  :markdown
-    The [API docs](./api.html#model_Model) cover many additional methods available like [count](./api.html#model_Model.count), [mapReduce](./api.html#model_Model.mapReduce), [aggregate](./api.html#model_Model.aggregate), and [more](./api.html#model_Model.findOneAndRemove).
-
-  h3#next Next Up
-  :markdown
-    Now that we've covered `Models`, let's take a look at [Documents](/docs/documents.html).
diff --git a/docs/plugins.md b/docs/plugins.md
new file mode 100644
index 00000000000..23a015b4ff7
--- /dev/null
+++ b/docs/plugins.md
@@ -0,0 +1,116 @@
+## Plugins
+
+Schemas are pluggable, that is, they allow for applying pre-packaged capabilities to extend their functionality. This is a very powerful feature.
+
+<ul class="toc">
+  <li><a href="#example">Example</a></li>
+  <li><a href="#global">Global Plugins</a></li>
+  <li><a href="#apply-plugins-before-compiling-models">Apply Plugins Before Compiling Models</a></li>
+  <li><a href="#official">Officially Supported Plugins</a></li>
+</ul>
+
+<h3 id="example"><a href="#example">Example</a></h3>
+
+Plugins are a tool for reusing logic in multiple schemas. Suppose you have
+several models in your database and want to add a `loadedAt` property
+to each one. Just create a plugin once and apply it to each `Schema`:
+
+```javascript
+// loadedAt.js
+module.exports = function loadedAtPlugin(schema, options) {
+  schema.virtual('loadedAt').
+    get(function() { return this._loadedAt; }).
+    set(function(v) { this._loadedAt = v; });
+
+  schema.post(['find', 'findOne'], function(docs) {
+    if (!Array.isArray(docs)) {
+      docs = [docs];
+    }
+    const now = new Date();
+    for (const doc of docs) {
+      doc.loadedAt = now;
+    }
+  });
+};
+
+// game-schema.js
+const loadedAtPlugin = require('./loadedAt');
+const gameSchema = new Schema({ ... });
+gameSchema.plugin(loadedAtPlugin);
+
+// player-schema.js
+const loadedAtPlugin = require('./loadedAt');
+const playerSchema = new Schema({ ... });
+playerSchema.plugin(loadedAtPlugin);
+```
+
+We just added last-modified behavior to both our `Game` and `Player` schemas and declared an index on the `lastMod` path of our Games to boot. Not bad for a few lines of code.
+
+<h3 id="global"><a href="#global">Global Plugins</a></h3>
+
+Want to register a plugin for all schemas? The mongoose singleton has a
+`.plugin()` function that registers a plugin for every schema. For
+example:
+
+```javascript
+const mongoose = require('mongoose');
+mongoose.plugin(require('./loadedAt'));
+
+const gameSchema = new Schema({ ... });
+const playerSchema = new Schema({ ... });
+// `loadedAtPlugin` gets attached to both schemas
+const Game = mongoose.model('Game', gameSchema);
+const Player = mongoose.model('Player', playerSchema);
+```
+
+<h3 id="apply-plugins-before-compiling-models"><a href="#apply-plugins-before-compiling-models">Apply Plugins Before Compiling Models</a></h3>
+
+Because many plugins rely on [middleware](/docs/middleware.html), you should make sure to apply plugins **before**
+you call `mongoose.model()` or `conn.model()`. Otherwise, [any middleware the plugin registers won't get applied](/docs/middleware.html#defining).
+
+```javascript
+// loadedAt.js
+module.exports = function loadedAtPlugin(schema, options) {
+  schema.virtual('loadedAt').
+    get(function() { return this._loadedAt; }).
+    set(function(v) { this._loadedAt = v; });
+
+  schema.post(['find', 'findOne'], function(docs) {
+    if (!Array.isArray(docs)) {
+      docs = [docs];
+    }
+    const now = new Date();
+    for (const doc of docs) {
+      doc.loadedAt = now;
+    }
+  });
+};
+
+// game-schema.js
+const loadedAtPlugin = require('./loadedAt');
+const gameSchema = new Schema({ ... });
+const Game = mongoose.model('Game', gameSchema);
+
+// `find()` and `findOne()` hooks from `loadedAtPlugin()` won't get applied
+// because `mongoose.model()` was already called!
+gameSchema.plugin(loadedAtPlugin);
+```
+
+<h3 id="official"><a href="#official">Officially Supported Plugins</a></h3>
+
+The Mongoose team maintains several plugins that add cool new features to
+Mongoose. Here's a couple:
+
+* [mongoose-autopopulate](http://plugins.mongoosejs.io/plugins/autopopulate): Always [`populate()`](/docs/populate.html) certain fields in your Mongoose schemas.
+* [mongoose-lean-virtuals](http://plugins.mongoosejs.io/plugins/lean-virtuals): Attach virtuals to the results of Mongoose queries when using [`.lean()`](/docs/api.html#query_Query-lean).
+* [mongoose-cast-aggregation](https://www.npmjs.com/package/mongoose-cast-aggregation)
+
+You can find a full list of officially supported plugins on [Mongoose's plugins search site](https://plugins.mongoosejs.io/).
+
+### Community!
+
+Not only can you re-use schema functionality in your own projects, but you
+also reap the benefits of the Mongoose community as well. Any plugin
+published to [npm](https://npmjs.org/) and with
+'mongoose' as an [npm keyword](https://docs.npmjs.com/files/package.json#keywords)
+will show up on our [search results](http://plugins.mongoosejs.io) page.
diff --git a/docs/plugins.pug b/docs/plugins.pug
deleted file mode 100644
index 844ae43707c..00000000000
--- a/docs/plugins.pug
+++ /dev/null
@@ -1,138 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Plugins
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Schemas are pluggable, that is, they allow for applying pre-packaged capabilities to extend their functionality. This is a very powerful feature.
-
-    <ul class="toc">
-      <li><a href="#example">Example</a></li>
-      <li><a href="#global">Global Plugins</a></li>
-      <li><a href="#apply-plugins-before-compiling-models">Apply Plugins Before Compiling Models</a></li>
-      <li><a href="#official">Officially Supported Plugins</a></li>
-    </ul>
-
-    <h3 id="example"><a href="#example">Example</a></h3>
-
-    Plugins are a tool for reusing logic in multiple schemas. Suppose you have
-    several models in your database and want to add a `loadedAt` property
-    to each one. Just create a plugin once and apply it to each `Schema`:
-
-    ```javascript
-    // loadedAt.js
-    module.exports = function loadedAtPlugin(schema, options) {
-      schema.virtual('loadedAt').
-        get(function() { return this._loadedAt; }).
-        set(function(v) { this._loadedAt = v; });
-
-      schema.post(['find', 'findOne'], function(docs) {
-        if (!Array.isArray(docs)) {
-          docs = [docs];
-        }
-        const now = new Date();
-        for (const doc of docs) {
-          doc.loadedAt = now;
-        }
-      });
-    };
-
-    // game-schema.js
-    const loadedAtPlugin = require('./loadedAt');
-    const gameSchema = new Schema({ ... });
-    gameSchema.plugin(loadedAtPlugin);
-
-    // player-schema.js
-    const loadedAtPlugin = require('./loadedAt');
-    const playerSchema = new Schema({ ... });
-    playerSchema.plugin(loadedAtPlugin);
-    ```
-
-    We just added last-modified behavior to both our `Game` and `Player` schemas and declared an index on the `lastMod` path of our Games to boot. Not bad for a few lines of code.
-
-    <h3 id="global"><a href="#global">Global Plugins</a></h3>
-
-    Want to register a plugin for all schemas? The mongoose singleton has a
-    `.plugin()` function that registers a plugin for every schema. For
-    example:
-
-    ```javascript
-    const mongoose = require('mongoose');
-    mongoose.plugin(require('./loadedAt'));
-
-    const gameSchema = new Schema({ ... });
-    const playerSchema = new Schema({ ... });
-    // `loadedAtPlugin` gets attached to both schemas
-    const Game = mongoose.model('Game', gameSchema);
-    const Player = mongoose.model('Player', playerSchema);
-    ```
-
-    <h3 id="apply-plugins-before-compiling-models"><a href="#apply-plugins-before-compiling-models">Apply Plugins Before Compiling Models</a></h3>
-
-    Because many plugins rely on [middleware](/docs/middleware.html), you should make sure to apply plugins **before**
-    you call `mongoose.model()` or `conn.model()`. Otherwise, [any middleware the plugin registers won't get applied](/docs/middleware.html#defining).
-
-    ```javascript
-    // loadedAt.js
-    module.exports = function loadedAtPlugin(schema, options) {
-      schema.virtual('loadedAt').
-        get(function() { return this._loadedAt; }).
-        set(function(v) { this._loadedAt = v; });
-
-      schema.post(['find', 'findOne'], function(docs) {
-        if (!Array.isArray(docs)) {
-          docs = [docs];
-        }
-        const now = new Date();
-        for (const doc of docs) {
-          doc.loadedAt = now;
-        }
-      });
-    };
-
-    // game-schema.js
-    const loadedAtPlugin = require('./loadedAt');
-    const gameSchema = new Schema({ ... });
-    const Game = mongoose.model('Game', gameSchema);
-
-    // `find()` and `findOne()` hooks from `loadedAtPlugin()` won't get applied
-    // because `mongoose.model()` was already called!
-    gameSchema.plugin(loadedAtPlugin);
-    ```
-
-    <h3 id="official"><a href="#official">Officially Supported Plugins</a></h3>
-
-    The Mongoose team maintains several plugins that add cool new features to
-    Mongoose. Here's a couple:
-
-    * [mongoose-autopopulate](http://plugins.mongoosejs.io/plugins/autopopulate): Always [`populate()`](/docs/populate.html) certain fields in your Mongoose schemas.
-    * [mongoose-lean-virtuals](http://plugins.mongoosejs.io/plugins/lean-virtuals): Attach virtuals to the results of Mongoose queries when using [`.lean()`](/docs/api.html#query_Query-lean).
-    * [mongoose-cast-aggregation](https://www.npmjs.com/package/mongoose-cast-aggregation)
-
-    You can find a full list of officially supported plugins on [Mongoose's plugins search site](https://plugins.mongoosejs.io/).
-
-    ### Community!
-
-    Not only can you re-use schema functionality in your own projects, but you
-    also reap the benefits of the Mongoose community as well. Any plugin
-    published to [npm](https://npmjs.org/) and with
-    'mongoose' as an [npm keyword](https://docs.npmjs.com/files/package.json#keywords)
-    will show up on our [search results](http://plugins.mongoosejs.io) page.
diff --git a/docs/populate.md b/docs/populate.md
new file mode 100644
index 00000000000..c7c8bdbd8c5
--- /dev/null
+++ b/docs/populate.md
@@ -0,0 +1,816 @@
+## Populate
+
+MongoDB has the join-like [$lookup](https://docs.mongodb.com/manual/reference/operator/aggregation/lookup/) aggregation operator in versions >= 3.2. Mongoose has a more powerful alternative called `populate()`, which lets you reference documents in other collections.
+
+Population is the process of automatically replacing the specified paths in the document with document(s) from other collection(s). We may populate a single document, multiple documents, a plain object, multiple plain objects, or all objects returned from a query. Let's look at some examples.
+
+```javascript
+const mongoose = require('mongoose');
+const Schema = mongoose.Schema;
+
+const personSchema = Schema({
+  _id: Schema.Types.ObjectId,
+  name: String,
+  age: Number,
+  stories: [{ type: Schema.Types.ObjectId, ref: 'Story' }]
+});
+
+const storySchema = Schema({
+  author: { type: Schema.Types.ObjectId, ref: 'Person' },
+  title: String,
+  fans: [{ type: Schema.Types.ObjectId, ref: 'Person' }]
+});
+
+const Story = mongoose.model('Story', storySchema);
+const Person = mongoose.model('Person', personSchema);
+```
+
+So far we've created two [Models](./models.html). Our `Person` model has
+its `stories` field set to an array of `ObjectId`s. The `ref` option is
+what tells Mongoose which model to use during population, in our case
+the `Story` model. All `_id`s we store here must be document `_id`s from
+the `Story` model.
+
+**Note**: `ObjectId`, `Number`, `String`, and `Buffer` are valid for use
+as refs. However, you should use `ObjectId` unless you are an advanced
+user and have a good reason for doing so.
+
+<ul class="toc">
+  <li><a href="#saving-refs">Saving Refs</a></li>
+  <li><a href="#population">Population</a></li>
+  <li><a href="#checking-populated">Checking Whether a Field is Populated</a></li>
+  <li><a href="#setting-populated-fields">Setting Populated Fields</a></li>
+  <li><a href="#doc-not-found">What If There's No Foreign Document?</a></li>
+  <li><a href="#field-selection">Field Selection</a></li>
+  <li><a href="#populating-multiple-paths">Populating Multiple Paths</a></li>
+  <li><a href="#query-conditions">Query conditions and other options</a></li>
+  <li><a href="#refs-to-children">Refs to children</a></li>
+  <li><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></li>
+  <li><a href="#populate_multiple_documents">Populating multiple existing documents</a></li>
+  <li><a href="#deep-populate">Populating across multiple levels</a></li>
+  <li><a href="#cross-db-populate">Populating across Databases</a></li>
+  <li><a href="#dynamic-ref">Dynamic References via `refPath`</a></li>
+  <li><a href="#populate-virtuals">Populate Virtuals</a></li>
+  <li><a href="#count">Populate Virtuals: The Count Option</a></li>
+  <li><a href="#populating-maps">Populating Maps</a></li>
+  <li><a href="#populate-middleware">Populate in Middleware</a></li>
+</ul>
+
+<h3 id="saving-refs"><a href="#saving-refs">Saving refs</a></h3>
+
+Saving refs to other documents works the same way you normally save
+properties, just assign the `_id` value:
+
+```javascript
+const author = new Person({
+  _id: new mongoose.Types.ObjectId(),
+  name: 'Ian Fleming',
+  age: 50
+});
+
+author.save(function (err) {
+  if (err) return handleError(err);
+
+  const story1 = new Story({
+    title: 'Casino Royale',
+    author: author._id    // assign the _id from the person
+  });
+
+  story1.save(function (err) {
+    if (err) return handleError(err);
+    // that's it!
+  });
+});
+```
+
+<h3 id="population"><a href="#population">Population</a></h3>
+
+So far we haven't done anything much different. We've merely created a
+`Person` and a `Story`. Now let's take a look at populating our story's
+`author` using the query builder:
+
+```javascript
+Story.
+  findOne({ title: 'Casino Royale' }).
+  populate('author').
+  exec(function (err, story) {
+    if (err) return handleError(err);
+    console.log('The author is %s', story.author.name);
+    // prints "The author is Ian Fleming"
+  });
+```
+
+Populated paths are no longer set to their original `_id` , their value
+is replaced with the mongoose document returned from the database by
+performing a separate query before returning the results.
+
+Arrays of refs work the same way. Just call the
+[populate](./api.html#query_Query-populate) method on the query and an
+array of documents will be returned _in place_ of the original `_id`s.
+
+<h3 id="setting-populated-fields"><a href="#setting-populated-fields">Setting Populated Fields</a></h3>
+
+You can manually populate a property by setting it to a document. The document
+must be an instance of the model your `ref` property refers to.
+
+```javascript
+Story.findOne({ title: 'Casino Royale' }, function(error, story) {
+  if (error) {
+    return handleError(error);
+  }
+  story.author = author;
+  console.log(story.author.name); // prints "Ian Fleming"
+});
+```
+
+<h3 id="checking-populated"><a href="#checking-populated">Checking Whether a Field is Populated</a></h3>
+
+You can call the `populated()` function to check whether a field is populated.
+If `populated()` returns a [truthy value](https://masteringjs.io/tutorials/fundamentals/truthy),
+you can assume the field is populated.
+
+```javascript
+story.populated('author'); // truthy
+
+story.depopulate('author'); // Make `author` not populated anymore
+story.populated('author'); // undefined
+```
+
+A common reason for checking whether a path is populated is getting the `author`
+id. However, for your convenience, Mongoose adds a [`_id` getter to ObjectId instances](/docs/api/mongoose.html#mongoose_Mongoose-set)
+so you can use `story.author._id` regardless of whether `author` is populated.
+
+```javascript
+story.populated('author'); // truthy
+story.author._id; // ObjectId
+
+story.depopulate('author'); // Make `author` not populated anymore
+story.populated('author'); // undefined
+
+story.author instanceof ObjectId; // true
+story.author._id; // ObjectId, because Mongoose adds a special getter
+```
+
+<h3 id="doc-not-found"><a href="#doc-not-found">What If There's No Foreign Document?</a></h3>
+
+Mongoose populate doesn't behave like conventional
+[SQL joins](https://www.w3schools.com/sql/sql_join.asp). When there's no
+document, `story.author` will be `null`. This is analogous to a
+[left join](https://www.w3schools.com/sql/sql_join_left.asp) in SQL.
+
+```javascript
+await Person.deleteMany({ name: 'Ian Fleming' });
+
+const story = await Story.findOne({ title: 'Casino Royale' }).populate('author');
+story.author; // `null`
+```
+
+If you have an array of `authors` in your `storySchema`, `populate()` will
+give you an empty array instead.
+
+```javascript
+const storySchema = Schema({
+  authors: [{ type: Schema.Types.ObjectId, ref: 'Person' }],
+  title: String
+});
+
+// Later
+
+const story = await Story.findOne({ title: 'Casino Royale' }).populate('authors');
+story.authors; // `[]`
+```
+
+<h3 id="field-selection"><a href="#field-selection">Field Selection</a></h3>
+
+What if we only want a few specific fields returned for the populated
+documents? This can be accomplished by passing the usual
+[field name syntax](./api.html#query_Query-select) as the second argument
+to the populate method:
+
+```javascript
+Story.
+  findOne({ title: /casino royale/i }).
+  populate('author', 'name'). // only return the Persons name
+  exec(function (err, story) {
+    if (err) return handleError(err);
+
+    console.log('The author is %s', story.author.name);
+    // prints "The author is Ian Fleming"
+
+    console.log('The authors age is %s', story.author.age);
+    // prints "The authors age is null"
+  });
+```
+
+<h3 id="populating-multiple-paths"><a href="#populating-multiple-paths">Populating Multiple Paths</a></h3>
+
+What if we wanted to populate multiple paths at the same time?
+
+```javascript
+Story.
+  find(...).
+  populate('fans').
+  populate('author').
+  exec();
+```
+
+If you call `populate()` multiple times with the same path, only the last
+one will take effect.
+
+```javascript
+// The 2nd `populate()` call below overwrites the first because they
+// both populate 'fans'.
+Story.
+  find().
+  populate({ path: 'fans', select: 'name' }).
+  populate({ path: 'fans', select: 'email' });
+// The above is equivalent to:
+Story.find().populate({ path: 'fans', select: 'email' });
+```
+
+<h3 id="query-conditions"><a href="#query-conditions">Query conditions and other options</a></h3>
+
+What if we wanted to populate our fans array based on their age and
+select just their names?
+
+```javascript
+Story.
+  find().
+  populate({
+    path: 'fans',
+    match: { age: { $gte: 21 } },
+    // Explicitly exclude `_id`, see http://bit.ly/2aEfTdB
+    select: 'name -_id'
+  }).
+  exec();
+```
+
+The `match` option doesn't filter out `Story` documents. If there are no documents that satisfy `match`,
+you'll get a `Story` document with an empty `fans` array.
+
+For example, suppose you `populate()` a story's `author` and the `author` doesn't satisfy `match`. Then
+the story's `author` will be `null`.
+
+```javascript
+const story = await Story.
+  findOne({ title: 'Casino Royale' }).
+  populate({ path: 'author', name: { $ne: 'Ian Fleming' } }).
+  exec();
+story.author; // `null`
+```
+
+In general, there is no way to make `populate()` filter stories based on properties of the story's `author`.
+For example, the below query won't return any results, even though `author` is populated.
+
+```javascript
+const story = await Story.
+  findOne({ 'author.name': 'Ian Fleming' }).
+  populate('author').
+  exec();
+story; // null
+```
+
+If you want to filter stories by their author's name, you should use [denormalization](https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-3).
+
+<h3 id="limit-vs-perDocumentLimit"><a href="#limit-vs-perDocumentLimit">limit vs. perDocumentLimit</a></h3>
+
+Populate does support a `limit` option, however, it currently
+does **not** limit on a per-document basis for backwards compatibility. For example,
+suppose you have 2 stories:
+
+```javascript
+Story.create([
+  { title: 'Casino Royale', fans: [1, 2, 3, 4, 5, 6, 7, 8] },
+  { title: 'Live and Let Die', fans: [9, 10] }
+]);
+```
+
+If you were to `populate()` using the `limit` option, you
+would find that the 2nd story has 0 fans:
+
+```javascript
+const stories = Story.find().populate({
+  path: 'fans',
+  options: { limit: 2 }
+});
+
+stories[0].name; // 'Casino Royale'
+stories[0].fans.length; // 2
+
+// 2nd story has 0 fans!
+stories[1].name; // 'Live and Let Die'
+stories[1].fans.length; // 0
+```
+
+That's because, in order to avoid executing a separate query
+for each document, Mongoose instead queries for fans using
+`numDocuments * limit` as the limit. If you need the correct
+`limit`, you should use the `perDocumentLimit` option (new in Mongoose 5.9.0).
+Just keep in mind that `populate()` will execute a separate query
+for each story, which may cause `populate()` to be slower.
+
+```javascript
+const stories = await Story.find().populate({
+  path: 'fans',
+  // Special option that tells Mongoose to execute a separate query
+  // for each `story` to make sure we get 2 fans for each story.
+  perDocumentLimit: 2
+});
+
+stories[0].name; // 'Casino Royale'
+stories[0].fans.length; // 2
+
+stories[1].name; // 'Live and Let Die'
+stories[1].fans.length; // 2
+```
+
+<h3 id="refs-to-children"><a href="#refs-to-children">Refs to children</a></h3>
+
+We may find however, if we use the `author` object, we are unable to get a
+list of the stories. This is because no `story` objects were ever 'pushed'
+onto `author.stories`.
+
+There are two perspectives here. First, you may want the `author` know
+which stories are theirs. Usually, your schema should resolve
+one-to-many relationships by having a parent pointer in the 'many' side.
+But, if you have a good reason to want an array of child pointers, you
+can `push()` documents onto the array as shown below.
+
+```javascript
+author.stories.push(story1);
+author.save(callback);
+```
+
+This allows us to perform a `find` and `populate` combo:
+
+```javascript
+Person.
+  findOne({ name: 'Ian Fleming' }).
+  populate('stories'). // only works if we pushed refs to children
+  exec(function (err, person) {
+    if (err) return handleError(err);
+    console.log(person);
+  });
+```
+
+It is debatable that we really want two sets of pointers as they may get
+out of sync. Instead we could skip populating and directly `find()` the
+stories we are interested in.
+
+```javascript
+Story.
+  find({ author: author._id }).
+  exec(function (err, stories) {
+    if (err) return handleError(err);
+    console.log('The stories are an array: ', stories);
+  });
+```
+
+The documents returned from
+[query population](./api.html#query_Query-populate) become fully
+functional, `remove`able, `save`able documents unless the
+[lean](./api.html#query_Query-lean) option is specified. Do not confuse
+them with [sub docs](./subdocs.html). Take caution when calling its
+remove method because you'll be removing it from the database, not just
+the array.
+
+<h3 id="populate_an_existing_mongoose_document"><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></h3>
+
+If you have an existing mongoose document and want to populate some of its
+paths, you can use the
+[Document#populate()](./api.html#document_Document-populate) method.
+Just make sure you call [`Document#execPopulate()`](/docs/api/document.html#document_Document-execPopulate)
+to execute the `populate()`.
+
+```javascript
+const person = await Person.findOne({ name: 'Ian Fleming' });
+
+person.populated('stories'); // null
+
+// Call the `populate()` method on a document to populate a path.
+// Need to call `execPopulate()` to actually execute the `populate()`.
+await person.populate('stories').execPopulate();
+
+person.populated('stories'); // Array of ObjectIds
+person.stories[0].name; // 'Casino Royale'
+```
+
+The `Document#populate()` method supports chaining, so you can chain
+multiple `populate()` calls together.
+
+```javascript
+await person.populate('stories').populate('fans').execPopulate();
+person.populated('fans'); // Array of ObjectIds
+```
+
+<h3 id="populate_multiple_documents"><a href="#populate_multiple_documents">Populating multiple existing documents</a></h3>
+
+If we have one or many mongoose documents or even plain objects
+(_like [mapReduce](./api.html#model_Model.mapReduce) output_), we may
+populate them using the [Model.populate()](./api.html#model_Model.populate)
+method. This is what `Document#populate()`
+and `Query#populate()` use to populate documents.
+
+<h3 id="deep-populate"><a href="#deep-populate">Populating across multiple levels</a></h3>
+
+Say you have a user schema which keeps track of the user's friends.
+
+```javascript
+const userSchema = new Schema({
+  name: String,
+  friends: [{ type: ObjectId, ref: 'User' }]
+});
+```
+
+Populate lets you get a list of a user's friends, but what if you also
+wanted a user's friends of friends? Specify the `populate` option to tell
+mongoose to populate the `friends` array of all the user's friends:
+
+```javascript
+User.
+  findOne({ name: 'Val' }).
+  populate({
+    path: 'friends',
+    // Get friends of friends - populate the 'friends' array for every friend
+    populate: { path: 'friends' }
+  });
+```
+
+<h3 id="cross-db-populate"><a href="#cross-db-populate">Cross Database Populate</a></h3>
+
+Let's say you have a schema representing events, and a schema representing
+conversations. Each event has a corresponding conversation thread.
+
+```javascript
+const db1 = mongoose.createConnection('mongodb://localhost:27000/db1');
+const db2 = mongoose.createConnection('mongodb://localhost:27001/db2');
+
+const conversationSchema = new Schema({ numMessages: Number });
+const Conversation = db2.model('Conversation', conversationSchema);
+
+const eventSchema = new Schema({
+  name: String,
+  conversation: {
+    type: ObjectId,
+    ref: Conversation // `ref` is a **Model class**, not a string
+  }
+});
+const Event = db1.model('Event', eventSchema);
+```
+
+In the above example, events and conversations are stored in separate MongoDB
+databases. String `ref` will not work in this situation, because Mongoose
+assumes a string `ref` refers to a model name on the same connection. In
+the above example, the conversation model is registered on `db2`, not `db1`.
+
+```javascript
+// Works
+const events = await Event.
+  find().
+  populate('conversation');
+```
+
+This is known as a "cross-database populate," because it enables you to
+populate across MongoDB databases and even across MongoDB instances.
+
+If you don't have access to the model instance when defining your `eventSchema`,
+you can also pass [the model instance as an option to `populate()`](/docs/api/model.html#model_Model.populate).
+
+```javascript
+const events = await Event.
+  find().
+  // The `model` option specifies the model to use for populating.
+  populate({ path: 'conversation', model: Conversation });
+```
+
+<h3 id="dynamic-ref"><a href="#dynamic-ref">Dynamic References via `refPath`</a></h3>
+
+Mongoose can also populate from multiple collections based on the value
+of a property in the document. Let's say you're building a schema for
+storing comments. A user may comment on either a blog post or a product.
+
+```javascript
+const commentSchema = new Schema({
+  body: { type: String, required: true },
+  on: {
+    type: Schema.Types.ObjectId,
+    required: true,
+    // Instead of a hardcoded model name in `ref`, `refPath` means Mongoose
+    // will look at the `onModel` property to find the right model.
+    refPath: 'onModel'
+  },
+  onModel: {
+    type: String,
+    required: true,
+    enum: ['BlogPost', 'Product']
+  }
+});
+
+const Product = mongoose.model('Product', new Schema({ name: String }));
+const BlogPost = mongoose.model('BlogPost', new Schema({ title: String }));
+const Comment = mongoose.model('Comment', commentSchema);
+```
+
+The `refPath` option is a more sophisticated alternative to `ref`. If `ref`
+is just a string, Mongoose will always query the same model to find the
+populated subdocs. With `refPath`, you can configure what model Mongoose
+uses for each document.
+
+```javascript
+const book = await Product.create({ name: 'The Count of Monte Cristo' });
+const post = await BlogPost.create({ title: 'Top 10 French Novels' });
+
+const commentOnBook = await Comment.create({
+  body: 'Great read',
+  on: book._id,
+  onModel: 'Product'
+});
+
+const commentOnPost = await Comment.create({
+  body: 'Very informative',
+  on: post._id,
+  onModel: 'BlogPost'
+});
+
+// The below `populate()` works even though one comment references the
+// 'Product' collection and the other references the 'BlogPost' collection.
+const comments = await Comment.find().populate('on').sort({ body: 1 });
+comments[0].on.name; // "The Count of Monte Cristo"
+comments[1].on.title; // "Top 10 French Novels"
+```
+
+An alternative approach is to define separate `blogPost` and
+`product` properties on `commentSchema`, and then `populate()` on both
+properties.
+
+```javascript
+const commentSchema = new Schema({
+  body: { type: String, required: true },
+  product: {
+    type: Schema.Types.ObjectId,
+    required: true,
+    ref: 'Product'
+  },
+  blogPost: {
+    type: Schema.Types.ObjectId,
+    required: true,
+    ref: 'BlogPost'
+  }
+});
+
+// ...
+
+// The below `populate()` is equivalent to the `refPath` approach, you
+// just need to make sure you `populate()` both `product` and `blogPost`.
+const comments = await Comment.find().
+  populate('product').
+  populate('blogPost').
+  sort({ body: 1 });
+comments[0].product.name; // "The Count of Monte Cristo"
+comments[1].blogPost.title; // "Top 10 French Novels"
+```
+
+Defining separate `blogPost` and `product` properties works for this simple
+example. But, if you decide to allow users to also comment on articles or
+other comments, you'll need to add more properties to your schema. You'll
+also need an extra `populate()` call for every property, unless you use
+[mongoose-autopopulate](https://www.npmjs.com/package/mongoose-autopopulate).
+Using `refPath` means you only need 2 schema paths and one `populate()` call
+regardless of how many models your `commentSchema` can point to.
+
+<h3 id="populate-virtuals"><a href="#populate-virtuals">Populate Virtuals</a></h3>
+
+So far you've only populated based on the `_id` field. However, that's
+sometimes not the right choice.
+In particular, [arrays that grow without bound are a MongoDB anti-pattern](https://docs.mongodb.com/manual/tutorial/model-referenced-one-to-many-relationships-between-documents/).
+Using mongoose virtuals, you can define more sophisticated relationships
+between documents.
+
+```javascript
+const PersonSchema = new Schema({
+  name: String,
+  band: String
+});
+
+const BandSchema = new Schema({
+  name: String
+});
+BandSchema.virtual('members', {
+  ref: 'Person', // The model to use
+  localField: 'name', // Find people where `localField`
+  foreignField: 'band', // is equal to `foreignField`
+  // If `justOne` is true, 'members' will be a single doc as opposed to
+  // an array. `justOne` is false by default.
+  justOne: false,
+  options: { sort: { name: -1 }, limit: 5 } // Query options, see http://bit.ly/mongoose-query-options
+});
+
+const Person = mongoose.model('Person', PersonSchema);
+const Band = mongoose.model('Band', BandSchema);
+
+/**
+ * Suppose you have 2 bands: "Guns N' Roses" and "Motley Crue"
+ * And 4 people: "Axl Rose" and "Slash" with "Guns N' Roses", and
+ * "Vince Neil" and "Nikki Sixx" with "Motley Crue"
+ */
+Band.find({}).populate('members').exec(function(error, bands) {
+  /* `bands.members` is now an array of instances of `Person` */
+});
+```
+
+You can also use [the populate `match` option](http://thecodebarbarian.com/mongoose-5-5-static-hooks-and-populate-match-functions.html#populate-match-function)
+to add an additional filter to the `populate()` query. This is useful
+if you need to split up `populate()` data:
+
+```javascript
+const PersonSchema = new Schema({
+  name: String,
+  band: String,
+  isActive: Boolean
+});
+
+const BandSchema = new Schema({
+  name: String
+});
+BandSchema.virtual('activeMembers', {
+  ref: 'Person',
+  localField: 'name',
+  foreignField: 'band',
+  justOne: false,
+  match: { isActive: true }
+});
+BandSchema.virtual('formerMembers', {
+  ref: 'Person',
+  localField: 'name',
+  foreignField: 'band',
+  justOne: false,
+  match: { isActive: false }
+});
+```
+
+Keep in mind that virtuals are _not_ included in `toJSON()` and `toObject()` output by default. If you want populate
+virtuals to show up when using functions that rely on `JSON.stringify()`, like Express'
+[`res.json()` function](https://masteringjs.io/tutorials/express/json),
+set the `virtuals: true` option on your schema's `toJSON` options.
+
+```javascript
+const BandSchema = new Schema({ name: String }, {
+  toJSON: { virtuals: true }, // So `res.json()` and other `JSON.stringify()` functions include virtuals
+  toObject: { virtuals: true } // So `toObject()` output includes virtuals
+});
+```
+
+If you're using populate projections, make sure `foreignField` is included
+in the projection.
+
+```javascript
+Band.
+  find({}).
+  populate({ path: 'members', select: 'name' }).
+  exec(function(error, bands) {
+    // Won't work, foreign field `band` is not selected in the projection
+  });
+
+Band.
+  find({}).
+  populate({ path: 'members', select: 'name band' }).
+  exec(function(error, bands) {
+    // Works, foreign field `band` is selected
+  });
+```
+
+<h3 id="count"><a href="#count">Populate Virtuals: The Count Option</a></h3>
+
+Populate virtuals also support counting the number of documents with
+matching `foreignField` as opposed to the documents themselves. Set the
+`count` option on your virtual:
+
+```javascript
+const PersonSchema = new Schema({
+  name: String,
+  band: String
+});
+
+const BandSchema = new Schema({
+  name: String
+});
+BandSchema.virtual('numMembers', {
+  ref: 'Person', // The model to use
+  localField: 'name', // Find people where `localField`
+  foreignField: 'band', // is equal to `foreignField`
+  count: true // And only get the number of docs
+});
+
+// Later
+const doc = await Band.findOne({ name: 'Motley Crue' }).
+  populate('numMembers');
+doc.numMembers; // 2
+```
+
+<h3 id="populating-maps"><a href="#populating-maps">Populating Maps</a></h3>
+
+[Maps](/docs/schematypes.html#maps) are a type that represents an object with arbitrary
+string keys. For example, in the below schema, `members` is a map from strings to ObjectIds.
+
+```javascript
+const BandSchema = new Schema({
+  name: String,
+  members: {
+    type: Map,
+    of: {
+      type: 'ObjectId',
+      ref: 'Person'
+    }
+  }
+});
+const Band = mongoose.model('Band', bandSchema);
+```
+
+This map has a `ref`, which means you can use `populate()` to populate all the ObjectIds
+in the map. Suppose you have the below `band` document:
+
+```
+const person1 = new Person({ name: 'Vince Neil' });
+const person2 = new Person({ name: 'Mick Mars' });
+
+const band = new Band({
+  name: 'Motley Crue',
+  members: {
+    'singer': person1._id,
+    'guitarist': person2._id
+  }
+});
+```
+
+You can `populate()` every element in the map by populating the special path `members.$*`.
+`$*` is a special syntax that tells Mongoose to look at every key in the map.
+
+```javascript
+const band = await Band.findOne({ name: 'Motley Crue' }).populate('members.$*');
+
+band.members.get('singer'); // { _id: ..., name: 'Vince Neil' }
+```
+
+You can also populate paths in maps of subdocuments using `$*`. For example, suppose you
+have the below `librarySchema`:
+
+```javascript
+const librarySchema = new Schema({
+  name: String,
+  books: {
+    type: Map,
+    of: new Schema({
+      title: String,
+      author: {
+        type: 'ObjectId',
+        ref: 'Person'
+      }
+    })
+  }
+});
+const Library = mongoose.model('Library, librarySchema');
+```
+
+You can `populate()` every book's author by populating `books.$*.author`:
+
+```javascript
+const libraries = await Library.find().populate('books.$*.author');
+```
+
+<h3 id="populate-middleware"><a href="#populate-middleware">Populate in Middleware</a></h3>
+
+You can populate in either pre or post [hooks](http://mongoosejs.com/docs/middleware.html). If you want to
+always populate a certain field, check out the [mongoose-autopopulate plugin](http://npmjs.com/package/mongoose-autopopulate).
+
+```javascript
+// Always attach `populate()` to `find()` calls
+MySchema.pre('find', function() {
+  this.populate('user');
+});
+```
+
+```javascript
+// Always `populate()` after `find()` calls. Useful if you want to selectively populate
+// based on the docs found.
+MySchema.post('find', async function(docs) {
+  for (let doc of docs) {
+    if (doc.isPublic) {
+      await doc.populate('user').execPopulate();
+    }
+  }
+});
+```
+
+```javascript
+// `populate()` after saving. Useful for sending populated data back to the client in an
+// update API endpoint
+MySchema.post('save', function(doc, next) {
+  doc.populate('user').execPopulate().then(function() {
+    next();
+  });
+});
+```
+
+### Next Up
+
+Now that we've covered `populate()`, let's take a look at [discriminators](/docs/discriminators.html).
diff --git a/docs/populate.pug b/docs/populate.pug
deleted file mode 100644
index b0c193d3f98..00000000000
--- a/docs/populate.pug
+++ /dev/null
@@ -1,838 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Populate
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    MongoDB has the join-like [$lookup](https://docs.mongodb.com/manual/reference/operator/aggregation/lookup/) aggregation operator in versions >= 3.2. Mongoose has a more powerful alternative called `populate()`, which lets you reference documents in other collections.
-
-    Population is the process of automatically replacing the specified paths in the document with document(s) from other collection(s). We may populate a single document, multiple documents, a plain object, multiple plain objects, or all objects returned from a query. Let's look at some examples.
-
-    ```javascript
-    const mongoose = require('mongoose');
-    const Schema = mongoose.Schema;
-
-    const personSchema = Schema({
-      _id: Schema.Types.ObjectId,
-      name: String,
-      age: Number,
-      stories: [{ type: Schema.Types.ObjectId, ref: 'Story' }]
-    });
-
-    const storySchema = Schema({
-      author: { type: Schema.Types.ObjectId, ref: 'Person' },
-      title: String,
-      fans: [{ type: Schema.Types.ObjectId, ref: 'Person' }]
-    });
-
-    const Story = mongoose.model('Story', storySchema);
-    const Person = mongoose.model('Person', personSchema);
-    ```
-
-    So far we've created two [Models](./models.html). Our `Person` model has
-    its `stories` field set to an array of `ObjectId`s. The `ref` option is
-    what tells Mongoose which model to use during population, in our case
-    the `Story` model. All `_id`s we store here must be document `_id`s from
-    the `Story` model.
-
-    **Note**: `ObjectId`, `Number`, `String`, and `Buffer` are valid for use
-    as refs. However, you should use `ObjectId` unless you are an advanced
-    user and have a good reason for doing so.
-
-    <ul class="toc">
-      <li><a href="#saving-refs">Saving Refs</a></li>
-      <li><a href="#population">Population</a></li>
-      <li><a href="#checking-populated">Checking Whether a Field is Populated</a></li>
-      <li><a href="#setting-populated-fields">Setting Populated Fields</a></li>
-      <li><a href="#doc-not-found">What If There's No Foreign Document?</a></li>
-      <li><a href="#field-selection">Field Selection</a></li>
-      <li><a href="#populating-multiple-paths">Populating Multiple Paths</a></li>
-      <li><a href="#query-conditions">Query conditions and other options</a></li>
-      <li><a href="#refs-to-children">Refs to children</a></li>
-      <li><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></li>
-      <li><a href="#populate_multiple_documents">Populating multiple existing documents</a></li>
-      <li><a href="#deep-populate">Populating across multiple levels</a></li>
-      <li><a href="#cross-db-populate">Populating across Databases</a></li>
-      <li><a href="#dynamic-ref">Dynamic References via `refPath`</a></li>
-      <li><a href="#populate-virtuals">Populate Virtuals</a></li>
-      <li><a href="#count">Populate Virtuals: The Count Option</a></li>
-      <li><a href="#populating-maps">Populating Maps</a></li>
-      <li><a href="#populate-middleware">Populate in Middleware</a></li>
-    </ul>
-
-    <h3 id="saving-refs"><a href="#saving-refs">Saving refs</a></h3>
-
-    Saving refs to other documents works the same way you normally save
-    properties, just assign the `_id` value:
-
-    ```javascript
-    const author = new Person({
-      _id: new mongoose.Types.ObjectId(),
-      name: 'Ian Fleming',
-      age: 50
-    });
-
-    author.save(function (err) {
-      if (err) return handleError(err);
-
-      const story1 = new Story({
-        title: 'Casino Royale',
-        author: author._id    // assign the _id from the person
-      });
-
-      story1.save(function (err) {
-        if (err) return handleError(err);
-        // that's it!
-      });
-    });
-    ```
-
-    <h3 id="population"><a href="#population">Population</a></h3>
-
-    So far we haven't done anything much different. We've merely created a
-    `Person` and a `Story`. Now let's take a look at populating our story's
-    `author` using the query builder:
-
-    ```javascript
-    Story.
-      findOne({ title: 'Casino Royale' }).
-      populate('author').
-      exec(function (err, story) {
-        if (err) return handleError(err);
-        console.log('The author is %s', story.author.name);
-        // prints "The author is Ian Fleming"
-      });
-    ```
-
-    Populated paths are no longer set to their original `_id` , their value
-    is replaced with the mongoose document returned from the database by
-    performing a separate query before returning the results.
-
-    Arrays of refs work the same way. Just call the
-    [populate](./api.html#query_Query-populate) method on the query and an
-    array of documents will be returned _in place_ of the original `_id`s.
-
-    <h3 id="setting-populated-fields"><a href="#setting-populated-fields">Setting Populated Fields</a></h3>
-
-    You can manually populate a property by setting it to a document. The document
-    must be an instance of the model your `ref` property refers to.
-
-    ```javascript
-    Story.findOne({ title: 'Casino Royale' }, function(error, story) {
-      if (error) {
-        return handleError(error);
-      }
-      story.author = author;
-      console.log(story.author.name); // prints "Ian Fleming"
-    });
-    ```
-
-    <h3 id="checking-populated"><a href="#checking-populated">Checking Whether a Field is Populated</a></h3>
-
-    You can call the `populated()` function to check whether a field is populated.
-    If `populated()` returns a [truthy value](https://masteringjs.io/tutorials/fundamentals/truthy),
-    you can assume the field is populated.
-
-    ```javascript
-    story.populated('author'); // truthy
-
-    story.depopulate('author'); // Make `author` not populated anymore
-    story.populated('author'); // undefined
-    ```
-
-    A common reason for checking whether a path is populated is getting the `author`
-    id. However, for your convenience, Mongoose adds a [`_id` getter to ObjectId instances](/docs/api/mongoose.html#mongoose_Mongoose-set)
-    so you can use `story.author._id` regardless of whether `author` is populated.
-
-    ```javascript
-    story.populated('author'); // truthy
-    story.author._id; // ObjectId
-
-    story.depopulate('author'); // Make `author` not populated anymore
-    story.populated('author'); // undefined
-
-    story.author instanceof ObjectId; // true
-    story.author._id; // ObjectId, because Mongoose adds a special getter
-    ```
-
-    <h3 id="doc-not-found"><a href="#doc-not-found">What If There's No Foreign Document?</a></h3>
-
-    Mongoose populate doesn't behave like conventional
-    [SQL joins](https://www.w3schools.com/sql/sql_join.asp). When there's no
-    document, `story.author` will be `null`. This is analogous to a
-    [left join](https://www.w3schools.com/sql/sql_join_left.asp) in SQL.
-
-    ```javascript
-    await Person.deleteMany({ name: 'Ian Fleming' });
-
-    const story = await Story.findOne({ title: 'Casino Royale' }).populate('author');
-    story.author; // `null`
-    ```
-
-    If you have an array of `authors` in your `storySchema`, `populate()` will
-    give you an empty array instead.
-
-    ```javascript
-    const storySchema = Schema({
-      authors: [{ type: Schema.Types.ObjectId, ref: 'Person' }],
-      title: String
-    });
-
-    // Later
-
-    const story = await Story.findOne({ title: 'Casino Royale' }).populate('authors');
-    story.authors; // `[]`
-    ```
-
-    <h3 id="field-selection"><a href="#field-selection">Field Selection</a></h3>
-
-    What if we only want a few specific fields returned for the populated
-    documents? This can be accomplished by passing the usual
-    [field name syntax](./api.html#query_Query-select) as the second argument
-    to the populate method:
-
-    ```javascript
-    Story.
-      findOne({ title: /casino royale/i }).
-      populate('author', 'name'). // only return the Persons name
-      exec(function (err, story) {
-        if (err) return handleError(err);
-
-        console.log('The author is %s', story.author.name);
-        // prints "The author is Ian Fleming"
-
-        console.log('The authors age is %s', story.author.age);
-        // prints "The authors age is null"
-      });
-    ```
-
-    <h3 id="populating-multiple-paths"><a href="#populating-multiple-paths">Populating Multiple Paths</a></h3>
-
-    What if we wanted to populate multiple paths at the same time?
-
-    ```javascript
-    Story.
-      find(...).
-      populate('fans').
-      populate('author').
-      exec();
-    ```
-
-    If you call `populate()` multiple times with the same path, only the last
-    one will take effect.
-
-    ```javascript
-    // The 2nd `populate()` call below overwrites the first because they
-    // both populate 'fans'.
-    Story.
-      find().
-      populate({ path: 'fans', select: 'name' }).
-      populate({ path: 'fans', select: 'email' });
-    // The above is equivalent to:
-    Story.find().populate({ path: 'fans', select: 'email' });
-    ```
-
-    <h3 id="query-conditions"><a href="#query-conditions">Query conditions and other options</a></h3>
-
-    What if we wanted to populate our fans array based on their age and
-    select just their names?
-
-    ```javascript
-    Story.
-      find().
-      populate({
-        path: 'fans',
-        match: { age: { $gte: 21 } },
-        // Explicitly exclude `_id`, see http://bit.ly/2aEfTdB
-        select: 'name -_id'
-      }).
-      exec();
-    ```
-
-    The `match` option doesn't filter out `Story` documents. If there are no documents that satisfy `match`,
-    you'll get a `Story` document with an empty `fans` array.
-
-    For example, suppose you `populate()` a story's `author` and the `author` doesn't satisfy `match`. Then
-    the story's `author` will be `null`.
-
-    ```javascript
-    const story = await Story.
-      findOne({ title: 'Casino Royale' }).
-      populate({ path: 'author', name: { $ne: 'Ian Fleming' } }).
-      exec();
-    story.author; // `null`
-    ```
-
-    In general, there is no way to make `populate()` filter stories based on properties of the story's `author`.
-    For example, the below query won't return any results, even though `author` is populated.
-
-    ```javascript
-    const story = await Story.
-      findOne({ 'author.name': 'Ian Fleming' }).
-      populate('author').
-      exec();
-    story; // null
-    ```
-
-    If you want to filter stories by their author's name, you should use [denormalization](https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-3).
-
-    <h3 id="limit-vs-perDocumentLimit"><a href="#limit-vs-perDocumentLimit">limit vs. perDocumentLimit</a></h3>
-
-    Populate does support a `limit` option, however, it currently
-    does **not** limit on a per-document basis for backwards compatibility. For example,
-    suppose you have 2 stories:
-
-    ```javascript
-    Story.create([
-      { title: 'Casino Royale', fans: [1, 2, 3, 4, 5, 6, 7, 8] },
-      { title: 'Live and Let Die', fans: [9, 10] }
-    ]);
-    ```
-
-    If you were to `populate()` using the `limit` option, you
-    would find that the 2nd story has 0 fans:
-
-    ```javascript
-    const stories = Story.find().populate({
-      path: 'fans',
-      options: { limit: 2 }
-    });
-
-    stories[0].name; // 'Casino Royale'
-    stories[0].fans.length; // 2
-
-    // 2nd story has 0 fans!
-    stories[1].name; // 'Live and Let Die'
-    stories[1].fans.length; // 0
-    ```
-
-    That's because, in order to avoid executing a separate query
-    for each document, Mongoose instead queries for fans using
-    `numDocuments * limit` as the limit. If you need the correct
-    `limit`, you should use the `perDocumentLimit` option (new in Mongoose 5.9.0).
-    Just keep in mind that `populate()` will execute a separate query
-    for each story, which may cause `populate()` to be slower.
-
-    ```javascript
-    const stories = await Story.find().populate({
-      path: 'fans',
-      // Special option that tells Mongoose to execute a separate query
-      // for each `story` to make sure we get 2 fans for each story.
-      perDocumentLimit: 2
-    });
-
-    stories[0].name; // 'Casino Royale'
-    stories[0].fans.length; // 2
-
-    stories[1].name; // 'Live and Let Die'
-    stories[1].fans.length; // 2
-    ```
-
-    <h3 id="refs-to-children"><a href="#refs-to-children">Refs to children</a></h3>
-
-    We may find however, if we use the `author` object, we are unable to get a
-    list of the stories. This is because no `story` objects were ever 'pushed'
-    onto `author.stories`.
-
-    There are two perspectives here. First, you may want the `author` know
-    which stories are theirs. Usually, your schema should resolve
-    one-to-many relationships by having a parent pointer in the 'many' side.
-    But, if you have a good reason to want an array of child pointers, you
-    can `push()` documents onto the array as shown below.
-
-    ```javascript
-    author.stories.push(story1);
-    author.save(callback);
-    ```
-
-    This allows us to perform a `find` and `populate` combo:
-
-    ```javascript
-    Person.
-      findOne({ name: 'Ian Fleming' }).
-      populate('stories'). // only works if we pushed refs to children
-      exec(function (err, person) {
-        if (err) return handleError(err);
-        console.log(person);
-      });
-    ```
-
-    It is debatable that we really want two sets of pointers as they may get
-    out of sync. Instead we could skip populating and directly `find()` the
-    stories we are interested in.
-
-    ```javascript
-    Story.
-      find({ author: author._id }).
-      exec(function (err, stories) {
-        if (err) return handleError(err);
-        console.log('The stories are an array: ', stories);
-      });
-    ```
-
-    The documents returned from
-    [query population](./api.html#query_Query-populate) become fully
-    functional, `remove`able, `save`able documents unless the
-    [lean](./api.html#query_Query-lean) option is specified. Do not confuse
-    them with [sub docs](./subdocs.html). Take caution when calling its
-    remove method because you'll be removing it from the database, not just
-    the array.
-
-    <h3 id="populate_an_existing_mongoose_document"><a href="#populate_an_existing_mongoose_document">Populating an existing document</a></h3>
-
-    If you have an existing mongoose document and want to populate some of its
-    paths, you can use the
-    [Document#populate()](./api.html#document_Document-populate) method.
-    Just make sure you call [`Document#execPopulate()`](/docs/api/document.html#document_Document-execPopulate)
-    to execute the `populate()`.
-
-    ```javascript
-    const person = await Person.findOne({ name: 'Ian Fleming' });
-    
-    person.populated('stories'); // null
-
-    // Call the `populate()` method on a document to populate a path.
-    // Need to call `execPopulate()` to actually execute the `populate()`.
-    await person.populate('stories').execPopulate();
-
-    person.populated('stories'); // Array of ObjectIds
-    person.stories[0].name; // 'Casino Royale'
-    ```
-
-    The `Document#populate()` method supports chaining, so you can chain
-    multiple `populate()` calls together.
-
-    ```javascript
-    await person.populate('stories').populate('fans').execPopulate();
-    person.populated('fans'); // Array of ObjectIds
-    ```
-
-    <h3 id="populate_multiple_documents"><a href="#populate_multiple_documents">Populating multiple existing documents</a></h3>
-
-    If we have one or many mongoose documents or even plain objects
-    (_like [mapReduce](./api.html#model_Model.mapReduce) output_), we may
-    populate them using the [Model.populate()](./api.html#model_Model.populate)
-    method. This is what `Document#populate()`
-    and `Query#populate()` use to populate documents.
-
-    <h3 id="deep-populate"><a href="#deep-populate">Populating across multiple levels</a></h3>
-
-    Say you have a user schema which keeps track of the user's friends.
-
-    ```javascript
-    const userSchema = new Schema({
-      name: String,
-      friends: [{ type: ObjectId, ref: 'User' }]
-    });
-    ```
-
-    Populate lets you get a list of a user's friends, but what if you also
-    wanted a user's friends of friends? Specify the `populate` option to tell
-    mongoose to populate the `friends` array of all the user's friends:
-
-    ```javascript
-    User.
-      findOne({ name: 'Val' }).
-      populate({
-        path: 'friends',
-        // Get friends of friends - populate the 'friends' array for every friend
-        populate: { path: 'friends' }
-      });
-    ```
-
-    <h3 id="cross-db-populate"><a href="#cross-db-populate">Cross Database Populate</a></h3>
-
-    Let's say you have a schema representing events, and a schema representing
-    conversations. Each event has a corresponding conversation thread.
-
-    ```javascript
-    const db1 = mongoose.createConnection('mongodb://localhost:27000/db1');
-    const db2 = mongoose.createConnection('mongodb://localhost:27001/db2');
-
-    const conversationSchema = new Schema({ numMessages: Number });
-    const Conversation = db2.model('Conversation', conversationSchema);
-
-    const eventSchema = new Schema({
-      name: String,
-      conversation: {
-        type: ObjectId,
-        ref: Conversation // `ref` is a **Model class**, not a string
-      }
-    });
-    const Event = db1.model('Event', eventSchema);
-    ```
-
-    In the above example, events and conversations are stored in separate MongoDB
-    databases. String `ref` will not work in this situation, because Mongoose
-    assumes a string `ref` refers to a model name on the same connection. In
-    the above example, the conversation model is registered on `db2`, not `db1`.
-
-    ```javascript
-    // Works
-    const events = await Event.
-      find().
-      populate('conversation');
-    ```
-
-    This is known as a "cross-database populate," because it enables you to
-    populate across MongoDB databases and even across MongoDB instances.
-
-    If you don't have access to the model instance when defining your `eventSchema`,
-    you can also pass [the model instance as an option to `populate()`](/docs/api/model.html#model_Model.populate).
-
-    ```javascript
-    const events = await Event.
-      find().
-      // The `model` option specifies the model to use for populating.
-      populate({ path: 'conversation', model: Conversation });
-    ```
-
-    <h3 id="dynamic-ref"><a href="#dynamic-ref">Dynamic References via `refPath`</a></h3>
-
-    Mongoose can also populate from multiple collections based on the value
-    of a property in the document. Let's say you're building a schema for
-    storing comments. A user may comment on either a blog post or a product.
-
-    ```javascript
-    const commentSchema = new Schema({
-      body: { type: String, required: true },
-      on: {
-        type: Schema.Types.ObjectId,
-        required: true,
-        // Instead of a hardcoded model name in `ref`, `refPath` means Mongoose
-        // will look at the `onModel` property to find the right model.
-        refPath: 'onModel'
-      },
-      onModel: {
-        type: String,
-        required: true,
-        enum: ['BlogPost', 'Product']
-      }
-    });
-
-    const Product = mongoose.model('Product', new Schema({ name: String }));
-    const BlogPost = mongoose.model('BlogPost', new Schema({ title: String }));
-    const Comment = mongoose.model('Comment', commentSchema);
-    ```
-
-    The `refPath` option is a more sophisticated alternative to `ref`. If `ref`
-    is just a string, Mongoose will always query the same model to find the
-    populated subdocs. With `refPath`, you can configure what model Mongoose
-    uses for each document.
-
-    ```javascript
-    const book = await Product.create({ name: 'The Count of Monte Cristo' });
-    const post = await BlogPost.create({ title: 'Top 10 French Novels' });
-
-    const commentOnBook = await Comment.create({
-      body: 'Great read',
-      on: book._id,
-      onModel: 'Product'
-    });
-
-    const commentOnPost = await Comment.create({
-      body: 'Very informative',
-      on: post._id,
-      onModel: 'BlogPost'
-    });
-
-    // The below `populate()` works even though one comment references the
-    // 'Product' collection and the other references the 'BlogPost' collection.
-    const comments = await Comment.find().populate('on').sort({ body: 1 });
-    comments[0].on.name; // "The Count of Monte Cristo"
-    comments[1].on.title; // "Top 10 French Novels"
-    ```
-
-    An alternative approach is to define separate `blogPost` and
-    `product` properties on `commentSchema`, and then `populate()` on both
-    properties.
-
-    ```javascript
-    const commentSchema = new Schema({
-      body: { type: String, required: true },
-      product: {
-        type: Schema.Types.ObjectId,
-        required: true,
-        ref: 'Product'
-      },
-      blogPost: {
-        type: Schema.Types.ObjectId,
-        required: true,
-        ref: 'BlogPost'
-      }
-    });
-
-    // ...
-
-    // The below `populate()` is equivalent to the `refPath` approach, you
-    // just need to make sure you `populate()` both `product` and `blogPost`.
-    const comments = await Comment.find().
-      populate('product').
-      populate('blogPost').
-      sort({ body: 1 });
-    comments[0].product.name; // "The Count of Monte Cristo"
-    comments[1].blogPost.title; // "Top 10 French Novels"
-    ```
-
-    Defining separate `blogPost` and `product` properties works for this simple
-    example. But, if you decide to allow users to also comment on articles or
-    other comments, you'll need to add more properties to your schema. You'll
-    also need an extra `populate()` call for every property, unless you use
-    [mongoose-autopopulate](https://www.npmjs.com/package/mongoose-autopopulate).
-    Using `refPath` means you only need 2 schema paths and one `populate()` call
-    regardless of how many models your `commentSchema` can point to.
-
-    <h3 id="populate-virtuals"><a href="#populate-virtuals">Populate Virtuals</a></h3>
-
-    So far you've only populated based on the `_id` field. However, that's
-    sometimes not the right choice.
-    In particular, [arrays that grow without bound are a MongoDB anti-pattern](https://docs.mongodb.com/manual/tutorial/model-referenced-one-to-many-relationships-between-documents/).
-    Using mongoose virtuals, you can define more sophisticated relationships
-    between documents.
-
-    ```javascript
-    const PersonSchema = new Schema({
-      name: String,
-      band: String
-    });
-
-    const BandSchema = new Schema({
-      name: String
-    });
-    BandSchema.virtual('members', {
-      ref: 'Person', // The model to use
-      localField: 'name', // Find people where `localField`
-      foreignField: 'band', // is equal to `foreignField`
-      // If `justOne` is true, 'members' will be a single doc as opposed to
-      // an array. `justOne` is false by default.
-      justOne: false,
-      options: { sort: { name: -1 }, limit: 5 } // Query options, see http://bit.ly/mongoose-query-options
-    });
-
-    const Person = mongoose.model('Person', PersonSchema);
-    const Band = mongoose.model('Band', BandSchema);
-
-    /**
-     * Suppose you have 2 bands: "Guns N' Roses" and "Motley Crue"
-     * And 4 people: "Axl Rose" and "Slash" with "Guns N' Roses", and
-     * "Vince Neil" and "Nikki Sixx" with "Motley Crue"
-     */
-    Band.find({}).populate('members').exec(function(error, bands) {
-      /* `bands.members` is now an array of instances of `Person` */
-    });
-    ```
-
-    You can also use [the populate `match` option](http://thecodebarbarian.com/mongoose-5-5-static-hooks-and-populate-match-functions.html#populate-match-function)
-    to add an additional filter to the `populate()` query. This is useful
-    if you need to split up `populate()` data:
-
-    ```javascript
-    const PersonSchema = new Schema({
-      name: String,
-      band: String,
-      isActive: Boolean
-    });
-
-    const BandSchema = new Schema({
-      name: String
-    });
-    BandSchema.virtual('activeMembers', {
-      ref: 'Person',
-      localField: 'name',
-      foreignField: 'band',
-      justOne: false,
-      match: { isActive: true }
-    });
-    BandSchema.virtual('formerMembers', {
-      ref: 'Person',
-      localField: 'name',
-      foreignField: 'band',
-      justOne: false,
-      match: { isActive: false }
-    });
-    ```
-
-    Keep in mind that virtuals are _not_ included in `toJSON()` and `toObject()` output by default. If you want populate
-    virtuals to show up when using functions that rely on `JSON.stringify()`, like Express'
-    [`res.json()` function](https://masteringjs.io/tutorials/express/json),
-    set the `virtuals: true` option on your schema's `toJSON` options.
-
-    ```javascript
-    const BandSchema = new Schema({ name: String }, {
-      toJSON: { virtuals: true }, // So `res.json()` and other `JSON.stringify()` functions include virtuals
-      toObject: { virtuals: true } // So `toObject()` output includes virtuals
-    });
-    ```
-
-    If you're using populate projections, make sure `foreignField` is included
-    in the projection.
-
-    ```javascript
-    Band.
-      find({}).
-      populate({ path: 'members', select: 'name' }).
-      exec(function(error, bands) {
-        // Won't work, foreign field `band` is not selected in the projection
-      });
-
-    Band.
-      find({}).
-      populate({ path: 'members', select: 'name band' }).
-      exec(function(error, bands) {
-        // Works, foreign field `band` is selected
-      });
-    ```
-
-    <h3 id="count"><a href="#count">Populate Virtuals: The Count Option</a></h3>
-
-    Populate virtuals also support counting the number of documents with
-    matching `foreignField` as opposed to the documents themselves. Set the
-    `count` option on your virtual:
-
-    ```javascript
-    const PersonSchema = new Schema({
-      name: String,
-      band: String
-    });
-
-    const BandSchema = new Schema({
-      name: String
-    });
-    BandSchema.virtual('numMembers', {
-      ref: 'Person', // The model to use
-      localField: 'name', // Find people where `localField`
-      foreignField: 'band', // is equal to `foreignField`
-      count: true // And only get the number of docs
-    });
-
-    // Later
-    const doc = await Band.findOne({ name: 'Motley Crue' }).
-      populate('numMembers');
-    doc.numMembers; // 2
-    ```
-
-    <h3 id="populating-maps"><a href="#populating-maps">Populating Maps</a></h3>
-
-    [Maps](/docs/schematypes.html#maps) are a type that represents an object with arbitrary
-    string keys. For example, in the below schema, `members` is a map from strings to ObjectIds.
-
-    ```javascript
-    const BandSchema = new Schema({
-      name: String,
-      members: {
-        type: Map,
-        of: {
-          type: 'ObjectId',
-          ref: 'Person'
-        }
-      }
-    });
-    const Band = mongoose.model('Band', bandSchema);
-    ```
-
-    This map has a `ref`, which means you can use `populate()` to populate all the ObjectIds
-    in the map. Suppose you have the below `band` document:
-
-    ```
-    const person1 = new Person({ name: 'Vince Neil' });
-    const person2 = new Person({ name: 'Mick Mars' });
-
-    const band = new Band({
-      name: 'Motley Crue',
-      members: {
-        'singer': person1._id,
-        'guitarist': person2._id
-      }
-    });
-    ```
-
-    You can `populate()` every element in the map by populating the special path `members.$*`.
-    `$*` is a special syntax that tells Mongoose to look at every key in the map.
-
-    ```javascript
-    const band = await Band.findOne({ name: 'Motley Crue' }).populate('members.$*');
-
-    band.members.get('singer'); // { _id: ..., name: 'Vince Neil' }
-    ```
-
-    You can also populate paths in maps of subdocuments using `$*`. For example, suppose you
-    have the below `librarySchema`:
-
-    ```javascript
-    const librarySchema = new Schema({
-      name: String,
-      books: {
-        type: Map,
-        of: new Schema({
-          title: String,
-          author: {
-            type: 'ObjectId',
-            ref: 'Person'
-          }
-        })
-      }
-    });
-    const Library = mongoose.model('Library, librarySchema');
-    ```
-
-    You can `populate()` every book's author by populating `books.$*.author`:
-
-    ```javascript
-    const libraries = await Library.find().populate('books.$*.author');
-    ```
-
-    <h3 id="populate-middleware"><a href="#populate-middleware">Populate in Middleware</a></h3>
-
-    You can populate in either pre or post [hooks](http://mongoosejs.com/docs/middleware.html). If you want to
-    always populate a certain field, check out the [mongoose-autopopulate plugin](http://npmjs.com/package/mongoose-autopopulate).
-
-    ```javascript
-    // Always attach `populate()` to `find()` calls
-    MySchema.pre('find', function() {
-      this.populate('user');
-    });
-    ```
-
-    ```javascript
-    // Always `populate()` after `find()` calls. Useful if you want to selectively populate
-    // based on the docs found.
-    MySchema.post('find', async function(docs) {
-      for (let doc of docs) {
-        if (doc.isPublic) {
-          await doc.populate('user').execPopulate();
-        }
-      }
-    });
-    ```
-
-    ```javascript
-    // `populate()` after saving. Useful for sending populated data back to the client in an
-    // update API endpoint
-    MySchema.post('save', function(doc, next) {
-      doc.populate('user').execPopulate().then(function() {
-        next();
-      });
-    });
-    ```
-
-    ### Next Up
-
-    Now that we've covered `populate()`, let's take a look at [discriminators](/docs/discriminators.html).
diff --git a/docs/queries.md b/docs/queries.md
new file mode 100644
index 00000000000..501fe37068f
--- /dev/null
+++ b/docs/queries.md
@@ -0,0 +1,245 @@
+## Queries
+
+Mongoose [models](./models.html) provide several static helper functions
+for [CRUD operations](https://en.wikipedia.org/wiki/Create,_read,_update_and_delete).
+Each of these functions returns a
+[mongoose `Query` object](http://mongoosejs.com/docs/api.html#Query).
+
+- [`Model.deleteMany()`](/docs/api.html#model_Model.deleteMany)
+- [`Model.deleteOne()`](/docs/api.html#model_Model.deleteOne)
+- [`Model.find()`](/docs/api.html#model_Model.find)
+- [`Model.findById()`](/docs/api.html#model_Model.findById)
+- [`Model.findByIdAndDelete()`](/docs/api.html#model_Model.findByIdAndDelete)
+- [`Model.findByIdAndRemove()`](/docs/api.html#model_Model.findByIdAndRemove)
+- [`Model.findByIdAndUpdate()`](/docs/api.html#model_Model.findByIdAndUpdate)
+- [`Model.findOne()`](/docs/api.html#model_Model.findOne)
+- [`Model.findOneAndDelete()`](/docs/api.html#model_Model.findOneAndDelete)
+- [`Model.findOneAndRemove()`](/docs/api.html#model_Model.findOneAndRemove)
+- [`Model.findOneAndReplace()`](/docs/api.html#model_Model.findOneAndReplace)
+- [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate)
+- [`Model.replaceOne()`](/docs/api.html#model_Model.replaceOne)
+- [`Model.updateMany()`](/docs/api.html#model_Model.updateMany)
+- [`Model.updateOne()`](/docs/api.html#model_Model.updateOne)
+
+A mongoose query can be executed in one of two ways. First, if you
+pass in a `callback` function, Mongoose will execute the query asynchronously
+and pass the results to the `callback`.
+
+A query also has a `.then()` function, and thus can be used as a promise.
+
+<ul class="toc">
+  <li><a href="#executing">Executing</a></li>
+  <li><a href="#queries-are-not-promises">Queries are Not Promises</a></li>
+  <li><a href="#refs">References to other documents</a></li>
+  <li><a href="#streaming">Streaming</a></li>
+  <li><a href="#versus-aggregation">Versus Aggregation</a></li>
+</ul>
+
+### Executing
+
+When executing a query with a `callback` function, you specify your query as a JSON document. The JSON document's syntax is the same as the [MongoDB shell](http://docs.mongodb.org/manual/tutorial/query-documents/).
+
+```javascript
+const Person = mongoose.model('Person', yourSchema);
+
+// find each person with a last name matching 'Ghost', selecting the `name` and `occupation` fields
+Person.findOne({ 'name.last': 'Ghost' }, 'name occupation', function (err, person) {
+  if (err) return handleError(err);
+  // Prints "Space Ghost is a talk show host".
+  console.log('%s %s is a %s.', person.name.first, person.name.last,
+    person.occupation);
+});
+```
+
+Mongoose executed the query and passed the results to `callback`. All callbacks in Mongoose use the pattern:
+`callback(error, result)`. If an error occurs executing the query, the `error` parameter will contain an error document, and `result`
+will be null. If the query is successful, the `error` parameter will be null, and the `result` will be populated with the results of the query.
+
+Anywhere a callback is passed to a query in Mongoose, the callback follows the pattern `callback(error, results)`. What `results` is depends on the operation: For `findOne()` it is a [potentially-null single document](./api.html#model_Model.findOne), `find()` a [list of documents](./api.html#model_Model.find), `count()` [the number of documents](./api.html#model_Model.count), `update()` the [number of documents affected](./api.html#model_Model.update), etc. The [API docs for Models](./api.html#model-js) provide more detail on what is passed to the callbacks.
+
+Now let's look at what happens when no `callback` is passed:
+
+```javascript
+// find each person with a last name matching 'Ghost'
+const query = Person.findOne({ 'name.last': 'Ghost' });
+
+// selecting the `name` and `occupation` fields
+query.select('name occupation');
+
+// execute the query at a later time
+query.exec(function (err, person) {
+  if (err) return handleError(err);
+  // Prints "Space Ghost is a talk show host."
+  console.log('%s %s is a %s.', person.name.first, person.name.last,
+    person.occupation);
+});
+```
+
+In the above code, the `query` variable is of type [Query](./api.html#query-js).
+A `Query` enables you to build up a query using chaining syntax, rather than specifying a JSON object.
+The below 2 examples are equivalent.
+
+```javascript
+// With a JSON doc
+Person.
+  find({
+    occupation: /host/,
+    'name.last': 'Ghost',
+    age: { $gt: 17, $lt: 66 },
+    likes: { $in: ['vaporizing', 'talking'] }
+  }).
+  limit(10).
+  sort({ occupation: -1 }).
+  select({ name: 1, occupation: 1 }).
+  exec(callback);
+
+// Using query builder
+Person.
+  find({ occupation: /host/ }).
+  where('name.last').equals('Ghost').
+  where('age').gt(17).lt(66).
+  where('likes').in(['vaporizing', 'talking']).
+  limit(10).
+  sort('-occupation').
+  select('name occupation').
+  exec(callback);
+```
+
+A full list of [Query helper functions can be found in the API docs](./api.html#query-js).
+
+<h3 id="queries-are-not-promises">
+  <a href="#queries-are-not-promises">
+    Queries are Not Promises
+  </a>
+</h3>
+
+Mongoose queries are **not** promises. They have a `.then()`
+function for [co](https://www.npmjs.com/package/co) and
+[async/await](http://thecodebarbarian.com/common-async-await-design-patterns-in-node.js.html)
+as a convenience. However, unlike promises, calling a query's `.then()`
+can execute the query multiple times.
+
+For example, the below code will execute 3 `updateMany()` calls, one
+because of the callback, and two because `.then()` is called twice.
+
+```javascript
+const q = MyModel.updateMany({}, { isDeleted: true }, function() {
+  console.log('Update 1');
+});
+
+q.then(() => console.log('Update 2'));
+q.then(() => console.log('Update 3'));
+```
+
+Don't mix using callbacks and promises with queries, or you may end up
+with duplicate operations. That's because passing a callback to a query function
+immediately executes the query, and calling [`then()`](https://masteringjs.io/tutorials/fundamentals/then)
+executes the query again.
+
+Mixing promises and callbacks can lead to duplicate entries in arrays.
+For example, the below code inserts 2 entries into the `tags` array, **not* just 1.
+
+```javascript
+const BlogPost = mongoose.model('BlogPost', new Schema({
+  title: String,
+  tags: [String]
+}));
+
+// Because there's both `await` **and** a callback, this `updateOne()` executes twice
+// and thus pushes the same string into `tags` twice.
+const update = { $push: { tags: ['javascript'] } };
+await BlogPost.updateOne({ title: 'Introduction to Promises' }, update, (err, res) => {
+  console.log(res);
+});
+```
+
+<h3 id="refs"><a href="#refs">References to other documents</a></h3>
+
+There are no joins in MongoDB but sometimes we still want references to
+documents in other collections. This is where [population](./populate.html)
+comes in. Read more about how to include documents from other collections in
+your query results [here](./api.html#query_Query-populate).
+
+<h3 id="streaming"><a href="#streaming">Streaming</a></h3>
+
+You can [stream](http://nodejs.org/api/stream.html) query results from
+MongoDB. You need to call the
+[Query#cursor()](./api.html#query_Query-cursor) function to return an instance of
+[QueryCursor](./api.html#query_Query-cursor).
+
+```javascript
+const cursor = Person.find({ occupation: /host/ }).cursor();
+
+for (let doc = await cursor.next(); doc != null; doc = await cursor.next()) {
+  console.log(doc); // Prints documents one at a time
+}
+```
+
+Iterating through a Mongoose query using [async iterators](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js.html)
+also creates a cursor.
+
+```javascript
+for await (const doc of Person.find()) {
+  console.log(doc); // Prints documents one at a time
+}
+```
+
+Cursors are subject to [cursor timeouts](https://stackoverflow.com/questions/21853178/when-a-mongodb-cursor-will-expire).
+By default, MongoDB will close your cursor after 10 minutes and subsequent
+`next()` calls will result in a `MongoError: cursor id 123 not found` error.
+To override this, set the `noCursorTimeout` option on your cursor.
+
+```javascript
+// MongoDB won't automatically close this cursor after 10 minutes.
+const cursor = Person.find().cursor().addCursorFlag('noCursorTimeout', true);
+```
+
+However, cursors can still time out because of [session idle timeouts](https://docs.mongodb.com/manual/reference/method/cursor.noCursorTimeout/#session-idle-timeout-overrides-nocursortimeout).
+So even a cursor with `noCursorTimeout` set will still time out after 30 minutes
+of inactivity. You can read more about working around session idle timeouts in the [MongoDB documentation](https://docs.mongodb.com/manual/reference/method/cursor.noCursorTimeout/#session-idle-timeout-overrides-nocursortimeout).
+
+<h3 id="versus-aggregation"><a href="#versus-aggregation">Versus Aggregation</a></h3>
+
+[Aggregation](https://mongoosejs.com/docs/api.html#aggregate_Aggregate) can
+do many of the same things that queries can. For example, below is
+how you can use `aggregate()` to find docs where `name.last = 'Ghost'`:
+
+```javascript
+const docs = await Person.aggregate([{ $match: { 'name.last': 'Ghost' } }]);
+```
+
+However, just because you can use `aggregate()` doesn't mean you should.
+In general, you should use queries where possible, and only use `aggregate()`
+when you absolutely need to.
+
+Unlike query results, Mongoose does **not** [`hydrate()`](/docs/api/model.html#model_Model.hydrate)
+aggregation results. Aggregation results are always POJOs, not Mongoose
+documents.
+
+```javascript
+const docs = await Person.aggregate([{ $match: { 'name.last': 'Ghost' } }]);
+
+docs[0] instanceof mongoose.Document; // false
+```
+
+Also, unlike query filters, Mongoose also doesn't
+[cast](/docs/tutorials/query_casting.html) aggregation pipelines. That means
+you're responsible for ensuring the values you pass in to an aggregation
+pipeline have the correct type.
+
+```javascript
+const doc = await Person.findOne();
+
+const idString = doc._id.toString();
+
+// Finds the `Person`, because Mongoose casts `idString` to an ObjectId
+const queryRes = await Person.findOne({ _id: idString });
+
+// Does **not** find the `Person`, because Mongoose doesn't cast aggregation
+// pipelines.
+const aggRes = await Person.aggregate([{ $match: { _id: idString } }])
+```
+
+<h3 id="next"><a href="#next">Next Up</a></h3>
+
+Now that we've covered `Queries`, let's take a look at [Validation](/docs/validation.html).
diff --git a/docs/queries.pug b/docs/queries.pug
deleted file mode 100644
index 82cf7600faf..00000000000
--- a/docs/queries.pug
+++ /dev/null
@@ -1,267 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Queries
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Mongoose [models](./models.html) provide several static helper functions
-    for [CRUD operations](https://en.wikipedia.org/wiki/Create,_read,_update_and_delete).
-    Each of these functions returns a
-    [mongoose `Query` object](http://mongoosejs.com/docs/api.html#Query).
-
-    - [`Model.deleteMany()`](/docs/api.html#model_Model.deleteMany)
-    - [`Model.deleteOne()`](/docs/api.html#model_Model.deleteOne)
-    - [`Model.find()`](/docs/api.html#model_Model.find)
-    - [`Model.findById()`](/docs/api.html#model_Model.findById)
-    - [`Model.findByIdAndDelete()`](/docs/api.html#model_Model.findByIdAndDelete)
-    - [`Model.findByIdAndRemove()`](/docs/api.html#model_Model.findByIdAndRemove)
-    - [`Model.findByIdAndUpdate()`](/docs/api.html#model_Model.findByIdAndUpdate)
-    - [`Model.findOne()`](/docs/api.html#model_Model.findOne)
-    - [`Model.findOneAndDelete()`](/docs/api.html#model_Model.findOneAndDelete)
-    - [`Model.findOneAndRemove()`](/docs/api.html#model_Model.findOneAndRemove)
-    - [`Model.findOneAndReplace()`](/docs/api.html#model_Model.findOneAndReplace)
-    - [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpdate)
-    - [`Model.replaceOne()`](/docs/api.html#model_Model.replaceOne)
-    - [`Model.updateMany()`](/docs/api.html#model_Model.updateMany)
-    - [`Model.updateOne()`](/docs/api.html#model_Model.updateOne)
-
-    A mongoose query can be executed in one of two ways. First, if you
-    pass in a `callback` function, Mongoose will execute the query asynchronously
-    and pass the results to the `callback`.
-
-    A query also has a `.then()` function, and thus can be used as a promise.
-
-    <ul class="toc">
-      <li><a href="#executing">Executing</a></li>
-      <li><a href="#queries-are-not-promises">Queries are Not Promises</a></li>
-      <li><a href="#refs">References to other documents</a></li>
-      <li><a href="#streaming">Streaming</a></li>
-      <li><a href="#versus-aggregation">Versus Aggregation</a></li>
-    </ul>
-
-    ### Executing
-
-    When executing a query with a `callback` function, you specify your query as a JSON document. The JSON document's syntax is the same as the [MongoDB shell](http://docs.mongodb.org/manual/tutorial/query-documents/).
-
-    ```javascript
-    const Person = mongoose.model('Person', yourSchema);
-
-    // find each person with a last name matching 'Ghost', selecting the `name` and `occupation` fields
-    Person.findOne({ 'name.last': 'Ghost' }, 'name occupation', function (err, person) {
-      if (err) return handleError(err);
-      // Prints "Space Ghost is a talk show host".
-      console.log('%s %s is a %s.', person.name.first, person.name.last,
-        person.occupation);
-    });
-    ```
-
-    Mongoose executed the query and passed the results to `callback`. All callbacks in Mongoose use the pattern:
-    `callback(error, result)`. If an error occurs executing the query, the `error` parameter will contain an error document, and `result`
-    will be null. If the query is successful, the `error` parameter will be null, and the `result` will be populated with the results of the query.
-
-    Anywhere a callback is passed to a query in Mongoose, the callback follows the pattern `callback(error, results)`. What `results` is depends on the operation: For `findOne()` it is a [potentially-null single document](./api.html#model_Model.findOne), `find()` a [list of documents](./api.html#model_Model.find), `count()` [the number of documents](./api.html#model_Model.count), `update()` the [number of documents affected](./api.html#model_Model.update), etc. The [API docs for Models](./api.html#model-js) provide more detail on what is passed to the callbacks.
-
-    Now let's look at what happens when no `callback` is passed:
-
-    ```javascript
-    // find each person with a last name matching 'Ghost'
-    const query = Person.findOne({ 'name.last': 'Ghost' });
-
-    // selecting the `name` and `occupation` fields
-    query.select('name occupation');
-
-    // execute the query at a later time
-    query.exec(function (err, person) {
-      if (err) return handleError(err);
-      // Prints "Space Ghost is a talk show host."
-      console.log('%s %s is a %s.', person.name.first, person.name.last,
-        person.occupation);
-    });
-    ```
-
-    In the above code, the `query` variable is of type [Query](./api.html#query-js).
-    A `Query` enables you to build up a query using chaining syntax, rather than specifying a JSON object.
-    The below 2 examples are equivalent.
-
-    ```javascript
-    // With a JSON doc
-    Person.
-      find({
-        occupation: /host/,
-        'name.last': 'Ghost',
-        age: { $gt: 17, $lt: 66 },
-        likes: { $in: ['vaporizing', 'talking'] }
-      }).
-      limit(10).
-      sort({ occupation: -1 }).
-      select({ name: 1, occupation: 1 }).
-      exec(callback);
-
-    // Using query builder
-    Person.
-      find({ occupation: /host/ }).
-      where('name.last').equals('Ghost').
-      where('age').gt(17).lt(66).
-      where('likes').in(['vaporizing', 'talking']).
-      limit(10).
-      sort('-occupation').
-      select('name occupation').
-      exec(callback);
-    ```
-
-    A full list of [Query helper functions can be found in the API docs](./api.html#query-js).
-
-    <h3 id="queries-are-not-promises">
-      <a href="#queries-are-not-promises">
-        Queries are Not Promises
-      </a>
-    </h3>
-
-    Mongoose queries are **not** promises. They have a `.then()`
-    function for [co](https://www.npmjs.com/package/co) and
-    [async/await](http://thecodebarbarian.com/common-async-await-design-patterns-in-node.js.html)
-    as a convenience. However, unlike promises, calling a query's `.then()`
-    can execute the query multiple times.
-
-    For example, the below code will execute 3 `updateMany()` calls, one
-    because of the callback, and two because `.then()` is called twice.
-
-    ```javascript
-    const q = MyModel.updateMany({}, { isDeleted: true }, function() {
-      console.log('Update 1');
-    });
-
-    q.then(() => console.log('Update 2'));
-    q.then(() => console.log('Update 3'));
-    ```
-
-    Don't mix using callbacks and promises with queries, or you may end up
-    with duplicate operations. That's because passing a callback to a query function
-    immediately executes the query, and calling [`then()`](https://masteringjs.io/tutorials/fundamentals/then)
-    executes the query again.
-
-    Mixing promises and callbacks can lead to duplicate entries in arrays.
-    For example, the below code inserts 2 entries into the `tags` array, **not* just 1.
-
-    ```javascript
-    const BlogPost = mongoose.model('BlogPost', new Schema({
-      title: String,
-      tags: [String]
-    }));
-
-    // Because there's both `await` **and** a callback, this `updateOne()` executes twice
-    // and thus pushes the same string into `tags` twice.
-    const update = { $push: { tags: ['javascript'] } };
-    await BlogPost.updateOne({ title: 'Introduction to Promises' }, update, (err, res) => {
-      console.log(res);
-    });
-    ```
-
-    <h3 id="refs"><a href="#refs">References to other documents</a></h3>
-
-    There are no joins in MongoDB but sometimes we still want references to
-    documents in other collections. This is where [population](./populate.html)
-    comes in. Read more about how to include documents from other collections in
-    your query results [here](./api.html#query_Query-populate).
-
-    <h3 id="streaming"><a href="#streaming">Streaming</a></h3>
-
-    You can [stream](http://nodejs.org/api/stream.html) query results from
-    MongoDB. You need to call the
-    [Query#cursor()](./api.html#query_Query-cursor) function to return an instance of
-    [QueryCursor](./api.html#query_Query-cursor).
-
-    ```javascript
-    const cursor = Person.find({ occupation: /host/ }).cursor();
-
-    for (let doc = await cursor.next(); doc != null; doc = await cursor.next()) {
-      console.log(doc); // Prints documents one at a time
-    }
-    ```
-
-    Iterating through a Mongoose query using [async iterators](https://thecodebarbarian.com/getting-started-with-async-iterators-in-node-js.html)
-    also creates a cursor.
-
-    ```javascript
-    for await (const doc of Person.find()) {
-      console.log(doc); // Prints documents one at a time
-    }
-    ```
-
-    Cursors are subject to [cursor timeouts](https://stackoverflow.com/questions/21853178/when-a-mongodb-cursor-will-expire).
-    By default, MongoDB will close your cursor after 10 minutes and subsequent
-    `next()` calls will result in a `MongoError: cursor id 123 not found` error.
-    To override this, set the `noCursorTimeout` option on your cursor.
-
-    ```javascript
-    // MongoDB won't automatically close this cursor after 10 minutes.
-    const cursor = Person.find().cursor().addCursorFlag('noCursorTimeout', true);
-    ```
-
-    However, cursors can still time out because of [session idle timeouts](https://docs.mongodb.com/manual/reference/method/cursor.noCursorTimeout/#session-idle-timeout-overrides-nocursortimeout).
-    So even a cursor with `noCursorTimeout` set will still time out after 30 minutes
-    of inactivity. You can read more about working around session idle timeouts in the [MongoDB documentation](https://docs.mongodb.com/manual/reference/method/cursor.noCursorTimeout/#session-idle-timeout-overrides-nocursortimeout).
-
-    <h3 id="versus-aggregation"><a href="#versus-aggregation">Versus Aggregation</a></h3>
-
-    [Aggregation](https://mongoosejs.com/docs/api.html#aggregate_Aggregate) can
-    do many of the same things that queries can. For example, below is
-    how you can use `aggregate()` to find docs where `name.last = 'Ghost'`:
-
-    ```javascript
-    const docs = await Person.aggregate([{ $match: { 'name.last': 'Ghost' } }]);
-    ```
-
-    However, just because you can use `aggregate()` doesn't mean you should.
-    In general, you should use queries where possible, and only use `aggregate()`
-    when you absolutely need to.
-
-    Unlike query results, Mongoose does **not** [`hydrate()`](/docs/api/model.html#model_Model.hydrate)
-    aggregation results. Aggregation results are always POJOs, not Mongoose
-    documents.
-
-    ```javascript
-    const docs = await Person.aggregate([{ $match: { 'name.last': 'Ghost' } }]);
-
-    docs[0] instanceof mongoose.Document; // false
-    ```
-
-    Also, unlike query filters, Mongoose also doesn't
-    [cast](/docs/tutorials/query_casting.html) aggregation pipelines. That means
-    you're responsible for ensuring the values you pass in to an aggregation
-    pipeline have the correct type.
-
-    ```javascript
-    const doc = await Person.findOne();
-
-    const idString = doc._id.toString();
-
-    // Finds the `Person`, because Mongoose casts `idString` to an ObjectId
-    const queryRes = await Person.findOne({ _id: idString });
-
-    // Does **not** find the `Person`, because Mongoose doesn't cast aggregation
-    // pipelines.
-    const aggRes = await Person.aggregate([{ $match: { _id: idString } }])
-    ```
-
-    <h3 id="next"><a href="#next">Next Up</a></h3>
-
-    Now that we've covered `Queries`, let's take a look at [Validation](/docs/validation.html).
diff --git a/docs/source/index.js b/docs/source/index.js
index 44d4f76f1a3..29437b6eb44 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -9,14 +9,14 @@ exports['docs/prior.pug'] = require('./prior');
 exports['docs/guides.pug'] = { guide: true, schema: true, title: 'Schemas' };
 exports['docs/guide.pug'] = { guide: true, schema: true, title: 'Schemas', acquit: true };
 exports['docs/schematypes.pug'] = { guide: true, schema: true, title: 'SchemaTypes' };
-exports['docs/middleware.pug'] = { guide: true, title: 'Middleware', acquit: true };
-exports['docs/plugins.pug'] = { guide: true, title: 'Plugins' };
-exports['docs/subdocs.pug'] = { guide: true, docs: true, title: 'SubDocuments' };
-exports['docs/documents.pug'] = { guide: true, docs: true, title: 'Documents' };
-exports['docs/models.pug'] = { guide: true, title: 'Models' };
-exports['docs/queries.pug'] = { guide: true, title: 'Queries' };
-exports['docs/populate.pug'] = { guide: true, title: 'Query Population' };
-exports['docs/migration.pug'] = { guide: true, title: 'Migration Guide' };
+exports['docs/middleware.md'] = { guide: true, title: 'Middleware', acquit: true, markdown: true };
+exports['docs/plugins.md'] = { guide: true, title: 'Plugins', markdown: true };
+exports['docs/subdocs.md'] = { guide: true, docs: true, title: 'SubDocuments', markdown: true };
+exports['docs/documents.md'] = { guide: true, docs: true, title: 'Documents', markdown: true };
+exports['docs/models.md'] = { guide: true, title: 'Models', markdown: true };
+exports['docs/queries.md'] = { guide: true, title: 'Queries', markdown: true };
+exports['docs/populate.md'] = { guide: true, title: 'Query Population', markdown: true };
+exports['docs/migration.md'] = { guide: true, title: 'Migration Guide', markdown: true };
 exports['docs/migrating_to_5.md'] = { guide: true, title: 'Migrating to Mongoose 5', markdown: true };
 exports['docs/contributing.md'] = { guide: true, title: 'Contributing', markdown: true };
 exports['docs/connections.md'] = { guide: true, title: 'Connecting to MongoDB', markdown: true };
diff --git a/docs/subdocs.md b/docs/subdocs.md
new file mode 100644
index 00000000000..1b3d778c968
--- /dev/null
+++ b/docs/subdocs.md
@@ -0,0 +1,392 @@
+## Subdocuments
+
+Subdocuments are documents embedded in other documents. In Mongoose, this
+means you can nest schemas in other schemas. Mongoose has two
+distinct notions of subdocuments: [arrays of subdocuments](https://masteringjs.io/tutorials/mongoose/array#document-arrays) and single nested
+subdocuments.
+
+```javascript
+const childSchema = new Schema({ name: 'string' });
+
+const parentSchema = new Schema({
+  // Array of subdocuments
+  children: [childSchema],
+  // Single nested subdocuments. Caveat: single nested subdocs only work
+  // in mongoose >= 4.2.0
+  child: childSchema
+});
+```
+
+Aside from code reuse, one important reason to use subdocuments is to create
+a path where there would otherwise not be one to allow for validation over
+a group of fields (e.g. dateRange.fromDate <= dateRange.toDate).
+
+<ul class="toc">
+  <li><a href="#what-is-a-subdocument-">What is a Subdocument?</a></li>
+  <li><a href="#subdocuments-versus-nested-paths">Subdocuments versus Nested Paths</a></li>
+  <li><a href="#subdocument-defaults">Subdocument Defaults</a></li>
+  <li><a href="#finding-a-subdocument">Finding a Subdocument</a></li>
+  <li><a href="#adding-subdocs-to-arrays">Adding Subdocs to Arrays</a></li>
+  <li><a href="#removing-subdocs">Removing Subdocs</a></li>
+  <li><a href="#subdoc-parents">Parents of Subdocs</a></li>
+  <li><a href="#altsyntaxarrays">Alternate declaration syntax for arrays</a></li>
+  <li><a href="#altsyntaxsingle">Alternate declaration syntax for single subdocuments</a></li>
+</ul>
+
+### What is a Subdocument?
+
+Subdocuments are similar to normal documents. Nested schemas can have
+[middleware](./middleware.html), [custom validation logic](./validation.html),
+virtuals, and any other feature top-level schemas can use. The major
+difference is that subdocuments are
+not saved individually, they are saved whenever their top-level parent
+document is saved.
+
+```javascript
+const Parent = mongoose.model('Parent', parentSchema);
+const parent = new Parent({ children: [{ name: 'Matt' }, { name: 'Sarah' }] })
+parent.children[0].name = 'Matthew';
+
+// `parent.children[0].save()` is a no-op, it triggers middleware but
+// does **not** actually save the subdocument. You need to save the parent
+// doc.
+parent.save(callback);
+```
+
+Subdocuments have `save` and `validate` [middleware](./middleware.html)
+just like top-level documents. Calling `save()` on the parent document triggers
+the `save()` middleware for all its subdocuments, and the same for `validate()`
+middleware.
+
+```javascript
+childSchema.pre('save', function (next) {
+  if ('invalid' == this.name) {
+    return next(new Error('#sadpanda'));
+  }
+  next();
+});
+
+const parent = new Parent({ children: [{ name: 'invalid' }] });
+parent.save(function (err) {
+  console.log(err.message) // #sadpanda
+});
+```
+
+Subdocuments' `pre('save')` and `pre('validate')` middleware execute
+**before** the top-level document's `pre('save')` but **after** the
+top-level document's `pre('validate')` middleware. This is because validating
+before `save()` is actually a piece of built-in middleware.
+
+```javascript
+// Below code will print out 1-4 in order
+const childSchema = new mongoose.Schema({ name: 'string' });
+
+childSchema.pre('validate', function(next) {
+  console.log('2');
+  next();
+});
+
+childSchema.pre('save', function(next) {
+  console.log('3');
+  next();
+});
+
+const parentSchema = new mongoose.Schema({
+  child: childSchema
+});
+
+parentSchema.pre('validate', function(next) {
+  console.log('1');
+  next();
+});
+
+parentSchema.pre('save', function(next) {
+  console.log('4');
+  next();
+});
+```
+
+### Subdocuments versus Nested Paths
+
+In Mongoose, nested paths are subtly different from subdocuments.
+For example, below are two schemas: one with `child` as a subdocument,
+and one with `child` as a nested path.
+
+```javascript
+// Subdocument
+const subdocumentSchema = new mongoose.Schema({
+  child: new mongoose.Schema({ name: String, age: Number })
+});
+const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
+
+// Nested path
+const nestedSchema = new mongoose.Schema({
+  child: { name: String, age: Number }
+});
+const Nested = mongoose.model('Nested', nestedSchema);
+```
+
+These two schemas look similar, and the documents in MongoDB will
+have the same structure with both schemas. But there are a few
+Mongoose-specific differences:
+
+First, instances of `Nested` never have `child === undefined`.
+You can always set subproperties of `child`, even if you don't set
+the `child` property. But instances of `Subdoc` can have `child === undefined`.
+
+```javascript
+const doc1 = new Subdoc({});
+doc1.child === undefined; // true
+doc1.child.name = 'test'; // Throws TypeError: cannot read property...
+
+const doc2 = new Nested({});
+doc2.child === undefined; // false
+console.log(doc2.child); // Prints 'MongooseDocument { undefined }'
+doc2.child.name = 'test'; // Works
+```
+
+Secondly, in Mongoose 5, [`Document#set()`](/docs/api/document.html#document_Document-set)
+merges when you call it on a nested path, but overwrites when you call
+it on a subdocument.
+
+```javascript
+const doc1 = new Subdoc({ child: { name: 'Luke', age: 19 } });
+doc1.set({ child: { age: 21 } });
+doc1.child; // { age: 21 }
+
+const doc2 = new Nested({ child: { name: 'Luke', age: 19 } });
+doc2.set({ child: { age: 21 } });
+doc2.child; // { name: Luke, age: 21 }
+```
+
+### Subdocument Defaults
+
+Subdocument paths are undefined by default, and Mongoose does
+not apply subdocument defaults unless you set the subdocument
+path to a non-nullish value.
+
+```javascript
+const subdocumentSchema = new mongoose.Schema({
+  child: new mongoose.Schema({
+    name: String,
+    age: {
+      type: Number,
+      default: 0
+    }
+  })
+});
+const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
+
+// Note that the `age` default has no effect, because `child`
+// is `undefined`.
+const doc = new Subdoc();
+doc.child; // undefined
+```
+
+However, if you set `doc.child` to any object, Mongoose will apply
+the `age` default if necessary.
+
+```javascript
+doc.child = {};
+// Mongoose applies the `age` default:
+doc.child.age; // 0
+```
+
+Mongoose applies defaults recursively, which means there's a nice
+workaround if you want to make sure Mongoose applies subdocument
+defaults: make the subdocument path default to an empty object.
+
+```javascript
+const childSchema = new mongoose.Schema({
+  name: String,
+  age: {
+    type: Number,
+    default: 0
+  }
+});
+const subdocumentSchema = new mongoose.Schema({
+  child: {
+    type: childSchema,
+    default: () => ({})
+  }
+});
+const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
+
+// Note that Mongoose sets `age` to its default value 0, because
+// `child` defaults to an empty object and Mongoose applies
+// defaults to that empty object.
+const doc = new Subdoc();
+doc.child; // { age: 0 }
+```
+
+### Finding a Subdocument
+
+Each subdocument has an `_id` by default. Mongoose document arrays have a
+special [id](./api.html#types_documentarray_MongooseDocumentArray-id) method
+for searching a document array to find a document with a given `_id`.
+```javascript
+const doc = parent.children.id(_id);
+```
+
+### Adding Subdocs to Arrays
+
+MongooseArray methods such as
+[push](./api.html#mongoosearray_MongooseArray-push),
+[unshift](./api.html#mongoosearray_MongooseArray-unshift),
+[addToSet](./api.html#mongoosearray_MongooseArray-addToSet),
+and others cast arguments to their proper types transparently:
+```javascript
+const Parent = mongoose.model('Parent');
+const parent = new Parent;
+
+// create a comment
+parent.children.push({ name: 'Liesl' });
+const subdoc = parent.children[0];
+console.log(subdoc) // { _id: '501d86090d371bab2c0341c5', name: 'Liesl' }
+subdoc.isNew; // true
+
+parent.save(function (err) {
+  if (err) return handleError(err)
+  console.log('Success!');
+});
+```
+
+Subdocs may also be created without adding them to the array by using the
+[create](./api.html#types_documentarray_MongooseDocumentArray.create)
+method of MongooseArrays.
+
+```javascript
+const newdoc = parent.children.create({ name: 'Aaron' });
+```
+
+### Removing Subdocs
+
+Each subdocument has it's own
+[remove](./api.html#types_embedded_EmbeddedDocument-remove) method. For
+an array subdocument, this is equivalent to calling `.pull()` on the
+subdocument. For a single nested subdocument, `remove()` is equivalent
+to setting the subdocument to `null`.
+
+```javascript
+// Equivalent to `parent.children.pull(_id)`
+parent.children.id(_id).remove();
+// Equivalent to `parent.child = null`
+parent.child.remove();
+parent.save(function (err) {
+  if (err) return handleError(err);
+  console.log('the subdocs were removed');
+});
+```
+
+<h3 id="subdoc-parents">Parents of Subdocs</h3>
+
+Sometimes, you need to get the parent of a subdoc. You can access the
+parent using the `parent()` function.
+
+```javascript
+const schema = new Schema({
+  docArr: [{ name: String }],
+  singleNested: new Schema({ name: String })
+});
+const Model = mongoose.model('Test', schema);
+
+const doc = new Model({
+  docArr: [{ name: 'foo' }],
+  singleNested: { name: 'bar' }
+});
+
+doc.singleNested.parent() === doc; // true
+doc.docArr[0].parent() === doc; // true
+```
+
+If you have a deeply nested subdoc, you can access the top-level document
+using the `ownerDocument()` function.
+
+```javascript
+const schema = new Schema({
+  level1: new Schema({
+    level2: new Schema({
+      test: String
+    })
+  })
+});
+const Model = mongoose.model('Test', schema);
+
+const doc = new Model({ level1: { level2: 'test' } });
+
+doc.level1.level2.parent() === doc; // false
+doc.level1.level2.parent() === doc.level1; // true
+doc.level1.level2.ownerDocument() === doc; // true
+```
+
+<h4 id="altsyntaxarrays">Alternate declaration syntax for arrays</h4>
+
+If you create a schema with an array of objects, Mongoose will automatically
+convert the object to a schema for you:
+
+```javascript
+const parentSchema = new Schema({
+  children: [{ name: 'string' }]
+});
+// Equivalent
+const parentSchema = new Schema({
+  children: [new Schema({ name: 'string' })]
+});
+```
+
+<h4 id="altsyntaxsingle">Alternate declaration syntax for single nested subdocuments</h4>
+
+Unlike document arrays, Mongoose 5 does not convert an objects in schemas
+into nested schemas. In the below example, `nested` is a _nested path_
+rather than a subdocument.
+
+```javascript
+const schema = new Schema({
+  nested: {
+    prop: String
+  }
+});
+```
+
+This leads to some surprising behavior when you attempt to define a
+nested path with validators or getters/setters.
+
+```javascript
+const schema = new Schema({
+  nested: {
+    // Do not do this! This makes `nested` a mixed path in Mongoose 5
+    type: { prop: String },
+    required: true
+  }
+});
+
+const schema = new Schema({
+  nested: {
+    // This works correctly
+    type: new Schema({ prop: String }),
+    required: true
+  }
+});
+```
+
+Surprisingly, declaring `nested` with an object `type` makes `nested`
+into a path of type [Mixed](/docs/schematypes.html#mixed). To instead
+make Mongoose automatically convert `type: { prop: String }` into
+`type: new Schema({ prop: String })`, set the `typePojoToMixed` option
+to `false`.
+
+```javascript
+const schema = new Schema({
+  nested: {
+    // Because of `typePojoToMixed`, Mongoose knows to
+    // wrap `{ prop: String }` in a `new Schema()`.
+    type: { prop: String },
+    required: true
+  }
+}, { typePojoToMixed: false });
+```
+
+### Next Up
+
+Now that we've covered Subdocuments, let's take a look at
+[querying](./queries.html).
diff --git a/docs/subdocs.pug b/docs/subdocs.pug
deleted file mode 100644
index 25eac08bac4..00000000000
--- a/docs/subdocs.pug
+++ /dev/null
@@ -1,408 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Subdocuments
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Subdocuments are documents embedded in other documents. In Mongoose, this
-    means you can nest schemas in other schemas. Mongoose has two
-    distinct notions of subdocuments: [arrays of subdocuments](https://masteringjs.io/tutorials/mongoose/array#document-arrays) and single nested
-    subdocuments.
-    ```javascript
-    const childSchema = new Schema({ name: 'string' });
-
-    const parentSchema = new Schema({
-      // Array of subdocuments
-      children: [childSchema],
-      // Single nested subdocuments. Caveat: single nested subdocs only work
-      // in mongoose >= 4.2.0
-      child: childSchema
-    });
-    ```
-    Aside from code reuse, one important reason to use subdocuments is to create
-    a path where there would otherwise not be one to allow for validation over
-    a group of fields (e.g. dateRange.fromDate <= dateRange.toDate).
-
-  :markdown
-    <ul class="toc">
-      <li><a href="#what-is-a-subdocument-">What is a Subdocument?</a></li>
-      <li><a href="#subdocuments-versus-nested-paths">Subdocuments versus Nested Paths</a></li>
-      <li><a href="#subdocument-defaults">Subdocument Defaults</a></li>
-      <li><a href="#finding-a-subdocument">Finding a Subdocument</a></li>
-      <li><a href="#adding-subdocs-to-arrays">Adding Subdocs to Arrays</a></li>
-      <li><a href="#removing-subdocs">Removing Subdocs</a></li>
-      <li><a href="#subdoc-parents">Parents of Subdocs</a></li>
-      <li><a href="#altsyntaxarrays">Alternate declaration syntax for arrays</a></li>
-      <li><a href="#altsyntaxsingle">Alternate declaration syntax for single subdocuments</a></li>
-    </ul>
-
-    ### What is a Subdocument?
-
-    Subdocuments are similar to normal documents. Nested schemas can have
-    [middleware](./middleware.html), [custom validation logic](./validation.html),
-    virtuals, and any other feature top-level schemas can use. The major
-    difference is that subdocuments are
-    not saved individually, they are saved whenever their top-level parent
-    document is saved.
-    ```javascript
-    const Parent = mongoose.model('Parent', parentSchema);
-    const parent = new Parent({ children: [{ name: 'Matt' }, { name: 'Sarah' }] })
-    parent.children[0].name = 'Matthew';
-
-    // `parent.children[0].save()` is a no-op, it triggers middleware but
-    // does **not** actually save the subdocument. You need to save the parent
-    // doc.
-    parent.save(callback);
-    ```
-  :markdown
-    Subdocuments have `save` and `validate` [middleware](./middleware.html)
-    just like top-level documents. Calling `save()` on the parent document triggers
-    the `save()` middleware for all its subdocuments, and the same for `validate()`
-    middleware.
-
-    ```javascript
-    childSchema.pre('save', function (next) {
-      if ('invalid' == this.name) {
-        return next(new Error('#sadpanda'));
-      }
-      next();
-    });
-
-    const parent = new Parent({ children: [{ name: 'invalid' }] });
-    parent.save(function (err) {
-      console.log(err.message) // #sadpanda
-    });
-    ```
-  :markdown
-    Subdocuments' `pre('save')` and `pre('validate')` middleware execute
-    **before** the top-level document's `pre('save')` but **after** the
-    top-level document's `pre('validate')` middleware. This is because validating
-    before `save()` is actually a piece of built-in middleware.
-
-    ```javascript
-    // Below code will print out 1-4 in order
-    const childSchema = new mongoose.Schema({ name: 'string' });
-
-    childSchema.pre('validate', function(next) {
-      console.log('2');
-      next();
-    });
-
-    childSchema.pre('save', function(next) {
-      console.log('3');
-      next();
-    });
-
-    const parentSchema = new mongoose.Schema({
-      child: childSchema
-    });
-
-    parentSchema.pre('validate', function(next) {
-      console.log('1');
-      next();
-    });
-
-    parentSchema.pre('save', function(next) {
-      console.log('4');
-      next();
-    });
-    ```
-
-    ### Subdocuments versus Nested Paths
-
-    In Mongoose, nested paths are subtly different from subdocuments.
-    For example, below are two schemas: one with `child` as a subdocument,
-    and one with `child` as a nested path.
-
-    ```javascript
-    // Subdocument
-    const subdocumentSchema = new mongoose.Schema({
-      child: new mongoose.Schema({ name: String, age: Number })
-    });
-    const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
-
-    // Nested path
-    const nestedSchema = new mongoose.Schema({
-      child: { name: String, age: Number }
-    });
-    const Nested = mongoose.model('Nested', nestedSchema);
-    ```
-
-    These two schemas look similar, and the documents in MongoDB will
-    have the same structure with both schemas. But there are a few
-    Mongoose-specific differences:
-
-    First, instances of `Nested` never have `child === undefined`.
-    You can always set subproperties of `child`, even if you don't set
-    the `child` property. But instances of `Subdoc` can have `child === undefined`.
-
-    ```javascript
-    const doc1 = new Subdoc({});
-    doc1.child === undefined; // true
-    doc1.child.name = 'test'; // Throws TypeError: cannot read property...
-
-    const doc2 = new Nested({});
-    doc2.child === undefined; // false
-    console.log(doc2.child); // Prints 'MongooseDocument { undefined }'
-    doc2.child.name = 'test'; // Works
-    ```
-
-    Secondly, in Mongoose 5, [`Document#set()`](/docs/api/document.html#document_Document-set)
-    merges when you call it on a nested path, but overwrites when you call
-    it on a subdocument.
-
-    ```javascript
-    const doc1 = new Subdoc({ child: { name: 'Luke', age: 19 } });
-    doc1.set({ child: { age: 21 } });
-    doc1.child; // { age: 21 }
-
-    const doc2 = new Nested({ child: { name: 'Luke', age: 19 } });
-    doc2.set({ child: { age: 21 } });
-    doc2.child; // { name: Luke, age: 21 }
-    ```
-
-    ### Subdocument Defaults
-
-    Subdocument paths are undefined by default, and Mongoose does
-    not apply subdocument defaults unless you set the subdocument
-    path to a non-nullish value.
-
-    ```javascript
-    const subdocumentSchema = new mongoose.Schema({
-      child: new mongoose.Schema({
-        name: String,
-        age: {
-          type: Number,
-          default: 0
-        }
-      })
-    });
-    const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
-
-    // Note that the `age` default has no effect, because `child`
-    // is `undefined`.
-    const doc = new Subdoc();
-    doc.child; // undefined
-    ```
-
-    However, if you set `doc.child` to any object, Mongoose will apply
-    the `age` default if necessary.
-
-    ```javascript
-    doc.child = {};
-    // Mongoose applies the `age` default:
-    doc.child.age; // 0
-    ```
-
-    Mongoose applies defaults recursively, which means there's a nice
-    workaround if you want to make sure Mongoose applies subdocument
-    defaults: make the subdocument path default to an empty object.
-
-    ```javascript
-    const childSchema = new mongoose.Schema({
-      name: String,
-      age: {
-        type: Number,
-        default: 0
-      }
-    });
-    const subdocumentSchema = new mongoose.Schema({
-      child: {
-        type: childSchema,
-        default: () => ({})
-      }
-    });
-    const Subdoc = mongoose.model('Subdoc', subdocumentSchema);
-
-    // Note that Mongoose sets `age` to its default value 0, because
-    // `child` defaults to an empty object and Mongoose applies
-    // defaults to that empty object.
-    const doc = new Subdoc();
-    doc.child; // { age: 0 }
-    ```
-
-  h3#finding-a-subdocument Finding a Subdocument
-  :markdown
-    Each subdocument has an `_id` by default. Mongoose document arrays have a
-    special [id](./api.html#types_documentarray_MongooseDocumentArray-id) method
-    for searching a document array to find a document with a given `_id`.
-    ```javascript
-    const doc = parent.children.id(_id);
-    ```
-  h3#adding-subdocs-to-arrays Adding Subdocs to Arrays
-  :markdown
-    MongooseArray methods such as
-    [push](./api.html#mongoosearray_MongooseArray-push),
-    [unshift](./api.html#mongoosearray_MongooseArray-unshift),
-    [addToSet](./api.html#mongoosearray_MongooseArray-addToSet),
-    and others cast arguments to their proper types transparently:
-    ```javascript
-    const Parent = mongoose.model('Parent');
-    const parent = new Parent;
-
-    // create a comment
-    parent.children.push({ name: 'Liesl' });
-    const subdoc = parent.children[0];
-    console.log(subdoc) // { _id: '501d86090d371bab2c0341c5', name: 'Liesl' }
-    subdoc.isNew; // true
-
-    parent.save(function (err) {
-      if (err) return handleError(err)
-      console.log('Success!');
-    });
-    ```
-  :markdown
-    Subdocs may also be created without adding them to the array by using the
-    [create](./api.html#types_documentarray_MongooseDocumentArray.create)
-    method of MongooseArrays.
-    ```javascript
-    const newdoc = parent.children.create({ name: 'Aaron' });
-    ```
-  h3#removing-subdocs Removing Subdocs
-  :markdown
-    Each subdocument has it's own
-    [remove](./api.html#types_embedded_EmbeddedDocument-remove) method. For
-    an array subdocument, this is equivalent to calling `.pull()` on the
-    subdocument. For a single nested subdocument, `remove()` is equivalent
-    to setting the subdocument to `null`.
-    ```javascript
-    // Equivalent to `parent.children.pull(_id)`
-    parent.children.id(_id).remove();
-    // Equivalent to `parent.child = null`
-    parent.child.remove();
-    parent.save(function (err) {
-      if (err) return handleError(err);
-      console.log('the subdocs were removed');
-    });
-    ```
-
-  h3#subdoc-parents Parents of Subdocs
-  :markdown
-    Sometimes, you need to get the parent of a subdoc. You can access the
-    parent using the `parent()` function.
-
-    ```javascript
-    const schema = new Schema({
-      docArr: [{ name: String }],
-      singleNested: new Schema({ name: String })
-    });
-    const Model = mongoose.model('Test', schema);
-
-    const doc = new Model({
-      docArr: [{ name: 'foo' }],
-      singleNested: { name: 'bar' }
-    });
-
-    doc.singleNested.parent() === doc; // true
-    doc.docArr[0].parent() === doc; // true
-    ```
-
-    If you have a deeply nested subdoc, you can access the top-level document
-    using the `ownerDocument()` function.
-
-    ```javascript
-    const schema = new Schema({
-      level1: new Schema({
-        level2: new Schema({
-          test: String
-        })
-      })
-    });
-    const Model = mongoose.model('Test', schema);
-
-    const doc = new Model({ level1: { level2: 'test' } });
-
-    doc.level1.level2.parent() === doc; // false
-    doc.level1.level2.parent() === doc.level1; // true
-    doc.level1.level2.ownerDocument() === doc; // true
-    ```
-
-  h4#altsyntaxarrays Alternate declaration syntax for arrays
-  :markdown
-    If you create a schema with an array of objects, Mongoose will automatically
-    convert the object to a schema for you:
-
-    ```javascript
-    const parentSchema = new Schema({
-      children: [{ name: 'string' }]
-    });
-    // Equivalent
-    const parentSchema = new Schema({
-      children: [new Schema({ name: 'string' })]
-    });
-    ```
-
-  h4#altsyntaxsingle Alternate declaration syntax for single nested subdocuments
-  :markdown
-    Unlike document arrays, Mongoose 5 does not convert an objects in schemas
-    into nested schemas. In the below example, `nested` is a _nested path_
-    rather than a subdocument.
-
-    ```javascript
-    const schema = new Schema({
-      nested: {
-        prop: String
-      }
-    });
-    ```
-
-    This leads to some surprising behavior when you attempt to define a
-    nested path with validators or getters/setters.
-
-    ```javascript
-    const schema = new Schema({
-      nested: {
-        // Do not do this! This makes `nested` a mixed path in Mongoose 5
-        type: { prop: String },
-        required: true
-      }
-    });
-
-    const schema = new Schema({
-      nested: {
-        // This works correctly
-        type: new Schema({ prop: String }),
-        required: true
-      }
-    });
-    ```
-
-    Surprisingly, declaring `nested` with an object `type` makes `nested`
-    into a path of type [Mixed](/docs/schematypes.html#mixed). To instead
-    make Mongoose automatically convert `type: { prop: String }` into
-    `type: new Schema({ prop: String })`, set the `typePojoToMixed` option
-    to `false`.
-
-    ```javascript
-    const schema = new Schema({
-      nested: {
-        // Because of `typePojoToMixed`, Mongoose knows to
-        // wrap `{ prop: String }` in a `new Schema()`.
-        type: { prop: String },
-        required: true
-      }
-    }, { typePojoToMixed: false });
-    ```
-
-  h3#next Next Up
-  :markdown
-    Now that we've covered Subdocuments, let's take a look at
-    [querying](./queries.html).

From 05e0d3583f48b6b40c6f2582bac311d3b413c239 Mon Sep 17 00:00:00 2001
From: "Stuart P. Bentley" <s@stuartpb.com>
Date: Fri, 21 May 2021 01:40:24 -0700
Subject: [PATCH 2066/2348] Document noListener option to useDb

---
 lib/connection.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/connection.js b/lib/connection.js
index 3f69089a58a..61442cb9a0b 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1496,6 +1496,7 @@ Connection.prototype.setClient = function setClient(client) {
  * @param {String} name The database name
  * @param {Object} [options]
  * @param {Boolean} [options.useCache=false] If true, cache results so calling `useDb()` multiple times with the same name only creates 1 connection object.
+ * @param {Boolean} [options.noListener=false] If true, the connection object will not make the db an event listener to the original connection. See [issue #9961](https://github.com/Automattic/mongoose/issues/9961).
  * @return {Connection} New Connection Object
  * @api public
  */

From e97440ef438f9a6d913c2b1c86a44ee304712990 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 11:02:00 -0400
Subject: [PATCH 2067/2348] perf(schema): avoid unnecessary `get()` call that
 adds extra overhead when creating nested arrays

Re: #9588
---
 lib/helpers/get.js  |  7 +++++++
 lib/schema/array.js | 18 +++++++-----------
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/lib/helpers/get.js b/lib/helpers/get.js
index dcb3881f713..9233fab3c1a 100644
--- a/lib/helpers/get.js
+++ b/lib/helpers/get.js
@@ -6,6 +6,13 @@
  */
 
 module.exports = function get(obj, path, def) {
+  if (path.indexOf('.') === -1) {
+    const _v = getProperty(obj, path);
+    if (_v == null) {
+      return def;
+    }
+    return _v;
+  }
   const parts = path.split('.');
   let rest = path;
   let cur = obj;
diff --git a/lib/schema/array.js b/lib/schema/array.js
index f2e49e77c96..1dc3ce0cca1 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -325,7 +325,8 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
   let l;
 
   if (Array.isArray(value)) {
-    if (!value.length && doc) {
+    const len = value.length;
+    if (!len && doc) {
       const indexes = doc.schema.indexedPaths();
 
       const arrayPath = this.path;
@@ -350,13 +351,9 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
       }
     }
 
-    if (!(value && value.isMongooseArray)) {
-      value = MongooseArray(value, get(options, 'path', null) || this._arrayPath || this.path, doc, this);
-    } else if (value && value.isMongooseArray) {
-      // We need to create a new array, otherwise change tracking will
-      // update the old doc (gh-4449)
-      value = MongooseArray(value, get(options, 'path', null) || this._arrayPath || this.path, doc, this);
-    }
+    options = options || {};
+
+    value = MongooseArray(value, options.path || this._arrayPath || this.path, doc, this);
 
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
     if (isPopulated && init) {
@@ -366,7 +363,6 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     const caster = this.caster;
     if (caster && this.casterConstructor !== Mixed) {
       try {
-        const len = value.length;
         for (i = 0; i < len; i++) {
           // Special case: number arrays disallow undefined.
           // Re: gh-840
@@ -381,8 +377,8 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
           if (caster.$isMongooseArray) {
             if (options != null && options.arrayPath != null) {
               opts.arrayPath = options.arrayPath + '.' + i;
-            } else if (this.caster._arrayParentPath != null) {
-              opts.arrayPath = this.caster._arrayParentPath + '.' + i;
+            } else if (caster._arrayParentPath != null) {
+              opts.arrayPath = caster._arrayParentPath + '.' + i;
             }
           }
           value[i] = caster.applySetters(value[i], doc, init, void 0, opts);

From 3d96d7bbf9aa779ce8a94f7cce5952324ef029af Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 11:59:24 -0400
Subject: [PATCH 2068/2348] perf(get): add benchmarks and extra cases to speed
 up `get()`

Re: #9588
---
 benchmarks/get.js   | 40 ++++++++++++++++++++++++++++++++++++++++
 lib/helpers/get.js  | 34 ++++++++++++++++++++++++++--------
 lib/schema/array.js |  3 ++-
 3 files changed, 68 insertions(+), 9 deletions(-)
 create mode 100644 benchmarks/get.js

diff --git a/benchmarks/get.js b/benchmarks/get.js
new file mode 100644
index 00000000000..a51d4ae65ae
--- /dev/null
+++ b/benchmarks/get.js
@@ -0,0 +1,40 @@
+'use strict';
+
+const get = require('../lib/helpers/get');
+
+let obj;
+
+// Single string
+obj = {};
+
+let start = Date.now();
+for (let i = 0; i < 10000000; ++i) {
+  get(obj, 'test', null);
+}
+console.log('Single string', Date.now() - start);
+
+// Array of length 1
+obj = {};
+start = Date.now();
+let arr = ['test'];
+for (let i = 0; i < 10000000; ++i) {
+  get(obj, arr, null);
+}
+console.log('Array of length 1', Date.now() - start);
+
+// String with dots
+obj = { a: { b: 1 } }
+start = Date.now();
+for (let i = 0; i < 10000000; ++i) {
+  get(obj, 'a.b', null);
+}
+console.log('String with dots', Date.now() - start);
+
+// Multi element array
+obj = { a: { b: 1 } }
+start = Date.now();
+arr = ['a', 'b'];
+for (let i = 0; i < 10000000; ++i) {
+  get(obj, arr, null);
+}
+console.log('Multi element array', Date.now() - start);
\ No newline at end of file
diff --git a/lib/helpers/get.js b/lib/helpers/get.js
index 9233fab3c1a..dbab30601dc 100644
--- a/lib/helpers/get.js
+++ b/lib/helpers/get.js
@@ -6,14 +6,30 @@
  */
 
 module.exports = function get(obj, path, def) {
-  if (path.indexOf('.') === -1) {
-    const _v = getProperty(obj, path);
-    if (_v == null) {
-      return def;
+  let parts;
+  let isPathArray = false;
+  if (typeof path === 'string') {
+    if (path.indexOf('.') === -1) {
+      const _v = getProperty(obj, path);
+      if (_v == null) {
+        return def;
+      }
+      return _v;
+    }
+
+    parts = path.split('.');
+  } else {
+    isPathArray = true;
+    parts = path;
+
+    if (parts.length === 1) {
+      const _v = getProperty(obj, parts[0]);
+      if (_v == null) {
+        return def;
+      }
+      return _v;
     }
-    return _v;
   }
-  const parts = path.split('.');
   let rest = path;
   let cur = obj;
   for (const part of parts) {
@@ -23,13 +39,15 @@ module.exports = function get(obj, path, def) {
 
     // `lib/cast.js` depends on being able to get dotted paths in updates,
     // like `{ $set: { 'a.b': 42 } }`
-    if (cur[rest] != null) {
+    if (!isPathArray && cur[rest] != null) {
       return cur[rest];
     }
 
     cur = getProperty(cur, part);
 
-    rest = rest.substr(part.length + 1);
+    if (!isPathArray) {
+      rest = rest.substr(part.length + 1);
+    }
   }
 
   return cur == null ? def : cur;
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 1dc3ce0cca1..0dbd04ee39a 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -25,6 +25,7 @@ let MongooseArray;
 let EmbeddedDoc;
 
 const isNestedArraySymbol = Symbol('mongoose#isNestedArray');
+const emptyOpts = Object.freeze({});
 
 /**
  * Array SchemaType constructor
@@ -351,7 +352,7 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
       }
     }
 
-    options = options || {};
+    options = options || emptyOpts;
 
     value = MongooseArray(value, options.path || this._arrayPath || this.path, doc, this);
 

From ba593f76ec55eb3f0e4f1cd50cf1526f1f3c85ed Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 13:01:04 -0400
Subject: [PATCH 2069/2348] perf(schematype): avoid cloning setters every time
 we run setters

Re: #9588
---
 lib/schema/array.js | 2 +-
 lib/schematype.js   | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index 0dbd04ee39a..e923d9036c0 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -376,7 +376,7 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
           // We only need `arrayPath` if this is a nested array, so
           // skip if possible.
           if (caster.$isMongooseArray) {
-            if (options != null && options.arrayPath != null) {
+            if (options.arrayPath != null) {
               opts.arrayPath = options.arrayPath + '.' + i;
             } else if (caster._arrayParentPath != null) {
               opts.arrayPath = caster._arrayParentPath + '.' + i;
diff --git a/lib/schematype.js b/lib/schematype.js
index c1479e16589..8c87fdb0349 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1071,8 +1071,8 @@ SchemaType.prototype._applySetters = function(value, scope, init) {
   }
   const setters = this.setters;
 
-  for (const setter of utils.clone(setters).reverse()) {
-    v = setter.call(scope, v, this);
+  for (let i = setters.length - 1; i >= 0; i--) {
+    v = setters[i].call(scope, v, this);
   }
 
   return v;

From 108aafb008d628f65ff1cc407d46029e9b6b174e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 13:55:25 -0400
Subject: [PATCH 2070/2348] perf(schema): only concat path and array index on
 nested document arrays #9588

---
 lib/schema/array.js         | 4 ++--
 lib/schema/documentarray.js | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/schema/array.js b/lib/schema/array.js
index e923d9036c0..d832381d159 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -377,9 +377,9 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
           // skip if possible.
           if (caster.$isMongooseArray) {
             if (options.arrayPath != null) {
-              opts.arrayPath = options.arrayPath + '.' + i;
+              opts.arrayPathIndex = i;
             } else if (caster._arrayParentPath != null) {
-              opts.arrayPath = caster._arrayParentPath + '.' + i;
+              opts.arrayPathIndex = i;
             }
           }
           value[i] = caster.applySetters(value[i], doc, init, void 0, opts);
diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index f4cc9907c0c..29baf2303a9 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -401,8 +401,8 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
     value = new MongooseDocumentArray(value, this.path, doc);
   }
 
-  if (options.arrayPath != null) {
-    value[arrayPathSymbol] = options.arrayPath;
+  if (options.arrayPathIndex != null) {
+    value[arrayPathSymbol] = this.path + '.' + options.arrayPathIndex;
   }
 
   const len = value.length;

From 18cff532df73965caffc977934ba21db6bd1884b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 14:12:04 -0400
Subject: [PATCH 2071/2348] docs: fix awkward sentence

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 61442cb9a0b..b32881289d2 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -1496,7 +1496,7 @@ Connection.prototype.setClient = function setClient(client) {
  * @param {String} name The database name
  * @param {Object} [options]
  * @param {Boolean} [options.useCache=false] If true, cache results so calling `useDb()` multiple times with the same name only creates 1 connection object.
- * @param {Boolean} [options.noListener=false] If true, the connection object will not make the db an event listener to the original connection. See [issue #9961](https://github.com/Automattic/mongoose/issues/9961).
+ * @param {Boolean} [options.noListener=false] If true, the connection object will not make the db listen to events on the original connection. See [issue #9961](https://github.com/Automattic/mongoose/issues/9961).
  * @return {Connection} New Connection Object
  * @api public
  */

From cdc83f84b2f1704050787756f122d46cd8c0bb00 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 14:22:03 -0400
Subject: [PATCH 2072/2348] fix: upgrade mongodb -> 3.6.8

Fix #10265
---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 093361444fd..8b8818193db 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.6",
+    "mongodb": "3.6.8",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.5",

From 6e97a0c4aedbc3e83b277bf691a2d7b8ea80bbc1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 15:21:22 -0400
Subject: [PATCH 2073/2348] test(populate): repro #10264

---
 test/model.populate.test.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index fd6e96823a6..0796c849897 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10459,7 +10459,29 @@ describe('model: populate:', function() {
       assert.equal(event.activities[0].speakers.length, 2);
       assert.equal(event.activities[0].speakers[0].dummy, '1');
       assert.equal(event.activities[0].speakers[1].dummy, '2');
+    });
+  });
 
+  it('supports populating an array of immutable elements (gh-10264)', function() {
+    const Cat = db.model('Cat', {
+      _id: String,
+      name: String,
+      friends: [{
+        immutable: true,
+        ref: 'Cat',
+        type: String
+      }]
+    });
+
+    return co(function*() {
+      const friend = new Cat({ _id: 'garfield', name: 'Garfield' });
+      yield friend.save();
+
+      const myCat = new Cat({ _id: 'arlene', name: 'Arlene', friends: [friend.id] });
+      yield myCat.save();
+
+      yield myCat.populate('friends').execPopulate();
+      assert.equal(myCat.friends[0].name, 'Garfield');
     });
   });
 });

From e20925fca1e96574dcbb51be8f7dd9cdb9c0cbe6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 15:26:25 -0400
Subject: [PATCH 2074/2348] fix(populate): skip applying setters when casting
 arrays for populate() to avoid issues with arrays of immutable elements

Fix #10264
---
 lib/helpers/populate/getModelsMapForPopulate.js | 2 +-
 lib/schema/array.js                             | 8 +++++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 74d036a29e0..74ba2a51b96 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -512,7 +512,7 @@ function convertTo_id(val, schema) {
       }
     }
     if (val.isMongooseArray && val.$schema()) {
-      return val.$schema().cast(val, val.$parent());
+      return val.$schema().cast(val, val.$parent(), false, void 0, { _skipSetters: true });
     }
 
     return [].concat(val);
diff --git a/lib/schema/array.js b/lib/schema/array.js
index d832381d159..43b492a5ef1 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -356,6 +356,8 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
 
     value = MongooseArray(value, options.path || this._arrayPath || this.path, doc, this);
 
+    const _skipSetters = options._skipSetters;
+
     const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
     if (isPopulated && init) {
       return value;
@@ -382,7 +384,11 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
               opts.arrayPathIndex = i;
             }
           }
-          value[i] = caster.applySetters(value[i], doc, init, void 0, opts);
+          if (_skipSetters) {
+            value[i] = caster.cast(value[i], doc, init, void 0, opts);
+          } else {
+            value[i] = caster.applySetters(value[i], doc, init, void 0, opts);
+          }
         }
       } catch (e) {
         // rethrow

From ffb811f0c1efafb127d45bdd546d9d7ce6979dc6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 21 May 2021 17:23:28 -0400
Subject: [PATCH 2075/2348] refactor: move several more docs pages from pug and
 acquit to markdown re: #10271

---
 docs/defaults.md          |   49 ++
 docs/guide.md             | 1280 ++++++++++++++++++++++++++++++++++++
 docs/guide.pug            | 1304 -------------------------------------
 docs/guides.md            |   47 ++
 docs/guides.pug           |   69 --
 docs/index.md             |  128 ++++
 docs/index.pug            |  132 ----
 docs/production.pug       |   13 -
 docs/schematypes.md       |  739 +++++++++++++++++++++
 docs/schematypes.pug      |  761 ----------------------
 docs/source/acquit.js     |    5 -
 docs/source/index.js      |   13 +-
 docs/source/production.js |    5 -
 website.js                |    3 +-
 14 files changed, 2252 insertions(+), 2296 deletions(-)
 create mode 100644 docs/defaults.md
 create mode 100644 docs/guide.md
 delete mode 100644 docs/guide.pug
 create mode 100644 docs/guides.md
 delete mode 100644 docs/guides.pug
 create mode 100644 docs/index.md
 delete mode 100644 docs/index.pug
 delete mode 100644 docs/production.pug
 create mode 100644 docs/schematypes.md
 delete mode 100644 docs/schematypes.pug
 delete mode 100644 docs/source/production.js

diff --git a/docs/defaults.md b/docs/defaults.md
new file mode 100644
index 00000000000..0dcc8d762c7
--- /dev/null
+++ b/docs/defaults.md
@@ -0,0 +1,49 @@
+## Defaults
+
+### Declaring Defaults in Your Schema
+
+Your schemas can define default values for certain paths. If you create
+a new document without that path set, the default will kick in.
+
+Note: Mongoose only applies a default if the value of the path is
+strictly `undefined`.
+
+```javascript
+[require:Declaring defaults in your schema]
+```
+
+### Default Functions
+
+You can also set the `default` schema option to a function. Mongoose will
+execute that function and use the return value as the default.
+
+```javascript
+[require:Default functions]
+```
+
+### The `setDefaultsOnInsert` Option
+
+By default, mongoose only applies defaults when you create a new document.
+It will **not** set defaults if you use `update()` and
+`findOneAndUpdate()`. However, mongoose 4.x lets you opt-in to this
+behavior using the `setDefaultsOnInsert` option.
+
+#### Important
+
+The `setDefaultsOnInsert` option relies on the
+[MongoDB `$setOnInsert` operator](https://docs.mongodb.org/manual/reference/operator/update/setOnInsert/).
+The `$setOnInsert` operator was introduced in MongoDB 2.4. If you're
+using MongoDB server < 2.4.0, do **not** use `setDefaultsOnInsert`.
+
+```javascript
+[require:The `setDefaultsOnInsert` option]
+```
+
+### Default functions and `this`
+
+Unless it is running on a query with `setDefaultsOnInsert`, a default
+function's `this` refers to the document.
+
+```javascript
+[require:Default functions and `this`]
+```
\ No newline at end of file
diff --git a/docs/guide.md b/docs/guide.md
new file mode 100644
index 00000000000..acf75a90487
--- /dev/null
+++ b/docs/guide.md
@@ -0,0 +1,1280 @@
+## Schemas
+
+If you haven't yet done so, please take a minute to read the [quickstart](./index.html) to get an idea of how Mongoose works.
+If you are migrating from 4.x to 5.x please take a moment to read the [migration guide](/docs/migrating_to_5.html).
+
+<ul class="toc">
+  <li><a href="#definition">Defining your schema</a></li>
+  <li><a href="#models">Creating a model</a></li>
+  <li><a href="#_id">Ids</a></li>
+  <li><a href="#methods">Instance methods</a></li>
+  <li><a href="#statics">Statics</a></li>
+  <li><a href="#query-helpers">Query Helpers</a></li>
+  <li><a href="#indexes">Indexes</a></li>
+  <li><a href="#virtuals">Virtuals</a></li>
+  <li><a href="#aliases">Aliases</a></li>
+  <li><a href="#options">Options</a></li>
+  <li><a href="#es6-classes">With ES6 Classes</a></li>
+  <li><a href="#plugins">Pluggable</a></li>
+  <li><a href="#further-reading">Further Reading</a></li>
+</ul>
+
+<h3 id="definition"><a href="#definition">Defining your schema</a></h3>
+
+Everything in Mongoose starts with a Schema. Each schema maps to a MongoDB
+collection and defines the shape of the documents within that collection.
+
+```javascript
+  import mongoose from 'mongoose';
+  const { Schema } = mongoose;
+
+  const blogSchema = new Schema({
+    title:  String, // String is shorthand for {type: String}
+    author: String,
+    body:   String,
+    comments: [{ body: String, date: Date }],
+    date: { type: Date, default: Date.now },
+    hidden: Boolean,
+    meta: {
+      votes: Number,
+      favs:  Number
+    }
+  });
+```
+
+If you want to add additional keys later, use the
+[Schema#add](./api.html#schema_Schema-add) method.
+
+Each key in our code `blogSchema` defines a property in our documents which
+will be cast to its associated [SchemaType](./api.html#schematype_SchemaType).
+For example, we've defined a property `title` which will be cast to the
+[String](./api.html#schema-string-js) SchemaType and property `date`
+which will be cast to a `Date` SchemaType.
+
+Notice above that if a property only requires a type, it can be specified using
+a shorthand notation (contrast the `title` property above with the `date`
+property).
+
+Keys may also be assigned nested objects containing further key/type definitions
+like the `meta` property above.  This will happen whenever a key's value is a POJO
+that doesn't have a `type` property.
+
+In these cases, Mongoose only creates actual schema paths for leaves
+in the tree. (like `meta.votes` and `meta.favs` above),
+and the branches do not have actual paths.  A side-effect of this is that `meta`
+above cannot have its own validation.  If validation is needed up the tree, a path
+needs to be created up the tree - see the [Subdocuments](./subdocs.html) section
+for more information on how to do this.  Also read the [Mixed](./schematypes.html)
+subsection of the SchemaTypes guide for some gotchas.
+
+The permitted SchemaTypes are:
+
+* [String](./schematypes.html#strings)
+* [Number](./schematypes.html#numbers)
+* [Date](./schematypes.html#dates)
+* [Buffer](./schematypes.html#buffers)
+* [Boolean](./schematypes.html#booleans)
+* [Mixed](./schematypes.html#mixed)
+* [ObjectId](./schematypes.html#objectids)
+* [Array](./schematypes.html#arrays)
+* [Decimal128](./api.html#mongoose_Mongoose-Decimal128)
+* [Map](./schematypes.html#maps)
+
+Read more about [SchemaTypes here](./schematypes.html).
+
+Schemas not only define the structure of your document and casting of
+properties, they also define document [instance methods](#methods),
+[static Model methods](#statics), [compound indexes](#indexes),
+and document lifecycle hooks called [middleware](./middleware.html).
+
+<h3 id="models"><a href="#models">Creating a model</a></h3>
+
+To use our schema definition, we need to convert our `blogSchema` into a
+[Model](./models.html) we can work with.
+To do so, we pass it into `mongoose.model(modelName, schema)`:
+
+```javascript
+  const Blog = mongoose.model('Blog', blogSchema);
+  // ready to go!
+```
+
+<h3 id="_id"><a href="#_id">Ids</a></h3>
+
+By default, Mongoose adds an `_id` property to your schemas.
+
+```javascript
+const schema = new Schema();
+
+schema.path('_id'); // ObjectId { ... }
+```
+
+When you create a new document with the automatically added
+`_id` property, Mongoose creates a new [`_id` of type ObjectId](https://masteringjs.io/tutorials/mongoose/objectid)
+to your document.
+
+```javascript
+const Model = mongoose.model('Test', schema);
+
+const doc = new Model();
+doc._id instanceof mongoose.Types.ObjectId; // true
+```
+
+You can also overwrite Mongoose's default `_id` with your
+own `_id`. Just be careful: Mongoose will refuse to save a
+document that doesn't have an `_id`, so you're responsible
+for setting `_id` if you define your own `_id` path.
+
+```javascript
+const schema = new Schema({ _id: Number });
+const Model = mongoose.model('Test', schema);
+
+const doc = new Model();
+await doc.save(); // Throws "document must have an _id before saving"
+
+doc._id = 1;
+await doc.save(); // works
+```
+
+<h3 id="methods"><a href="#methods">Instance methods</a></h3>
+
+Instances of `Models` are [documents](./documents.html). Documents have
+many of their own [built-in instance methods](./api/document.html).
+We may also define our own custom document instance methods.
+
+```javascript
+  // define a schema
+  const animalSchema = new Schema({ name: String, type: String });
+
+  // assign a function to the "methods" object of our animalSchema
+  animalSchema.methods.findSimilarTypes = function(cb) {
+    return mongoose.model('Animal').find({ type: this.type }, cb);
+  };
+```
+
+Now all of our `animal` instances have a `findSimilarTypes` method available
+to them.
+
+```javascript
+  const Animal = mongoose.model('Animal', animalSchema);
+  const dog = new Animal({ type: 'dog' });
+
+  dog.findSimilarTypes((err, dogs) => {
+    console.log(dogs); // woof
+  });
+```
+
+* Overwriting a default mongoose document method may lead to unpredictable results. See [this](./api.html#schema_Schema.reserved) for more details.
+* The example above uses the `Schema.methods` object directly to save an instance method. You can also use the `Schema.method()` helper as described [here](./api.html#schema_Schema-method).
+* Do **not** declare methods using ES6 arrow functions (`=>`). Arrow functions [explicitly prevent binding `this`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this), so your method will **not** have access to the document and the above examples will not work.
+
+<h3 id="statics"><a href="#statics">Statics</a></h3>
+
+You can also add static functions to your model. There are two equivalent
+ways to add a static:
+
+- Add a function property to `schema.statics`
+- Call the [`Schema#static()` function](/docs/api.html#schema_Schema-static)
+
+```javascript
+  // Assign a function to the "statics" object of our animalSchema
+  animalSchema.statics.findByName = function(name) {
+    return this.find({ name: new RegExp(name, 'i') });
+  };
+  // Or, equivalently, you can call `animalSchema.static()`.
+  animalSchema.static('findByBreed', function(breed) { return this.find({ breed }); });
+
+  const Animal = mongoose.model('Animal', animalSchema);
+  let animals = await Animal.findByName('fido');
+  animals = animals.concat(await Animal.findByBreed('Poodle'));
+```
+
+Do **not** declare statics using ES6 arrow functions (`=>`). Arrow functions [explicitly prevent binding `this`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this), so the above examples will not work because of the value of `this`.
+
+<h3 id="query-helpers"><a href="#query-helpers">Query Helpers</a></h3>
+
+You can also add query helper functions, which are like instance methods
+but for mongoose queries. Query helper methods let you extend mongoose's
+[chainable query builder API](./queries.html).
+
+```javascript
+  animalSchema.query.byName = function(name) {
+    return this.where({ name: new RegExp(name, 'i') })
+  };
+
+  const Animal = mongoose.model('Animal', animalSchema);
+
+  Animal.find().byName('fido').exec((err, animals) => {
+    console.log(animals);
+  });
+
+  Animal.findOne().byName('fido').exec((err, animal) => {
+    console.log(animal);
+  });
+```
+
+<h3 id="indexes"><a href="#indexes">Indexes</a></h3>
+
+MongoDB supports [secondary indexes](http://docs.mongodb.org/manual/indexes/).
+With mongoose, we define these indexes within our `Schema` [at](./api.html#schematype_SchemaType-index) [the](./api.html#schematype_SchemaType-unique) [path](./api.html#schematype_SchemaType-sparse) [level](./api.html#schema_date_SchemaDate-expires) or the `schema` level.
+Defining indexes at the schema level is necessary when creating
+[compound indexes](https://docs.mongodb.com/manual/core/index-compound/).
+
+```javascript
+  const animalSchema = new Schema({
+    name: String,
+    type: String,
+    tags: { type: [String], index: true } // field level
+  });
+
+  animalSchema.index({ name: 1, type: -1 }); // schema level
+```
+
+When your application starts up, Mongoose automatically calls [`createIndex`](https://docs.mongodb.com/manual/reference/method/db.collection.createIndex/#db.collection.createIndex) for each defined index in your schema.
+Mongoose will call `createIndex` for each index sequentially, and emit an 'index' event on the model when all the `createIndex` calls succeeded or when there was an error.
+While nice for development, it is recommended this behavior be disabled in production since index creation can cause a [significant performance impact](https://docs.mongodb.com/manual/core/index-creation/#index-build-impact-on-database-performance).
+Disable the behavior by setting the `autoIndex` option of your schema to `false`, or globally on the connection by setting the option `autoIndex` to `false`.
+
+```javascript
+  mongoose.connect('mongodb://user:pass@localhost:port/database', { autoIndex: false });
+  // or
+  mongoose.createConnection('mongodb://user:pass@localhost:port/database', { autoIndex: false });
+  // or
+  animalSchema.set('autoIndex', false);
+  // or
+  new Schema({..}, { autoIndex: false });
+```
+
+Mongoose will emit an `index` event on the model when indexes are done
+building or an error occurred.
+
+```javascript
+  // Will cause an error because mongodb has an _id index by default that
+  // is not sparse
+  animalSchema.index({ _id: 1 }, { sparse: true });
+  const Animal = mongoose.model('Animal', animalSchema);
+
+  Animal.on('index', error => {
+    // "_id index cannot be sparse"
+    console.log(error.message);
+  });
+```
+
+See also the [Model#ensureIndexes](./api.html#model_Model.ensureIndexes) method.
+
+<h3 id="virtuals"><a href="#virtuals">Virtuals</a></h3>
+
+[Virtuals](./api.html#schema_Schema-virtual) are document properties that
+you can get and set but that do not get persisted to MongoDB. The getters
+are useful for formatting or combining fields, while setters are useful for
+de-composing a single value into multiple values for storage.
+
+```javascript
+  // define a schema
+  const personSchema = new Schema({
+    name: {
+      first: String,
+      last: String
+    }
+  });
+
+  // compile our model
+  const Person = mongoose.model('Person', personSchema);
+
+  // create a document
+  const axl = new Person({
+    name: { first: 'Axl', last: 'Rose' }
+  });
+```
+
+Suppose you want to print out the person's full name. You could do it yourself:
+
+```javascript
+console.log(axl.name.first + ' ' + axl.name.last); // Axl Rose
+```
+
+But [concatenating](https://masteringjs.io/tutorials/fundamentals/string-concat) the first and
+last name every time can get cumbersome.
+And what if you want to do some extra processing on the name, like
+[removing diacritics](https://www.npmjs.com/package/diacritics)? A
+[virtual property getter](./api.html#virtualtype_VirtualType-get) lets you
+define a `fullName` property that won't get persisted to MongoDB.
+
+```javascript
+personSchema.virtual('fullName').get(function() {
+  return this.name.first + ' ' + this.name.last;
+});
+```
+
+Now, mongoose will call your getter function every time you access the
+`fullName` property:
+
+```javascript
+console.log(axl.fullName); // Axl Rose
+```
+
+If you use `toJSON()` or `toObject()` mongoose will *not* include virtuals
+by default. This includes the output of calling [`JSON.stringify()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify)
+on a Mongoose document, because [`JSON.stringify()` calls `toJSON()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#Description).
+Pass `{ virtuals: true }` to either
+[`toObject()`](./api.html#document_Document-toObject) or [`toJSON()`](./api.html#document_Document-toJSON).
+
+You can also add a custom setter to your virtual that will let you set both
+first name and last name via the `fullName` virtual.
+
+```javascript
+personSchema.virtual('fullName').
+  get(function() {
+    return this.name.first + ' ' + this.name.last;
+    }).
+  set(function(v) {
+    this.name.first = v.substr(0, v.indexOf(' '));
+    this.name.last = v.substr(v.indexOf(' ') + 1);
+  });
+
+axl.fullName = 'William Rose'; // Now `axl.name.first` is "William"
+```
+
+Virtual property setters are applied before other validation. So the example
+above would still work even if the `first` and `last` name fields were
+required.
+
+Only non-virtual properties work as part of queries and for field selection.
+Since virtuals are not stored in MongoDB, you can't query with them.
+
+You can [learn more about virtuals here](https://masteringjs.io/tutorials/mongoose/virtuals).
+
+<h3 id="aliases"><a href="#aliases">Aliases</a></h3>
+
+Aliases are a particular type of virtual where the getter and setter
+seamlessly get and set another property. This is handy for saving network
+bandwidth, so you can convert a short property name stored in the database
+into a longer name for code readability.
+
+```javascript
+const personSchema = new Schema({
+  n: {
+    type: String,
+    // Now accessing `name` will get you the value of `n`, and setting `name` will set the value of `n`
+    alias: 'name'
+  }
+});
+
+// Setting `name` will propagate to `n`
+const person = new Person({ name: 'Val' });
+console.log(person); // { n: 'Val' }
+console.log(person.toObject({ virtuals: true })); // { n: 'Val', name: 'Val' }
+console.log(person.name); // "Val"
+
+person.name = 'Not Val';
+console.log(person); // { n: 'Not Val' }
+```
+
+You can also declare aliases on nested paths. It is easier to use nested
+schemas and [subdocuments](/docs/subdocs.html), but you can also declare
+nested path aliases inline as long as you use the full nested path
+`nested.myProp` as the alias.
+
+```javascript
+[require:gh-6671]
+```
+
+<h3 id="options"><a href="#options">Options</a></h3>
+
+Schemas have a few configurable options which can be passed to the
+constructor or to the `set` method:
+
+```javascript
+new Schema({..}, options);
+
+// or
+
+const schema = new Schema({..});
+schema.set(option, value);
+```
+
+Valid options:
+
+- [autoIndex](#autoIndex)
+- [autoCreate](#autoCreate)
+- [bufferCommands](#bufferCommands)
+- [bufferTimeoutMS](#bufferTimeoutMS)
+- [capped](#capped)
+- [collection](#collection)
+- [discriminatorKey](#discriminatorKey)
+- [id](#id)
+- [_id](#_id)
+- [minimize](#minimize)
+- [read](#read)
+- [writeConcern](#writeConcern)
+- [shardKey](#shardKey)
+- [strict](#strict)
+- [strictQuery](#strictQuery)
+- [toJSON](#toJSON)
+- [toObject](#toObject)
+- [typeKey](#typeKey)
+- [typePojoToMixed](/docs/schematypes.html#mixed)
+- [useNestedStrict](#useNestedStrict)
+- [validateBeforeSave](#validateBeforeSave)
+- [versionKey](#versionKey)
+- [optimisticConcurrency](#optimisticConcurrency)
+- [collation](#collation)
+- [selectPopulatedPaths](#selectPopulatedPaths)
+- [skipVersioning](#skipVersioning)
+- [timestamps](#timestamps)
+- [storeSubdocValidationError](#storeSubdocValidationError)
+
+<h3 id="autoIndex"><a href="#autoIndex">option: autoIndex</a></h3>
+
+By default, Mongoose's [`init()` function](/docs/api.html#model_Model.init)
+creates all the indexes defined in your model's schema by calling
+[`Model.createIndexes()`](/docs/api.html#model_Model.createIndexes)
+after you successfully connect to MongoDB. Creating indexes automatically is
+great for development and test environments. But index builds can also create
+significant load on your production database. If you want to manage indexes
+carefully in production, you can set `autoIndex` to false.
+
+```javascript
+const schema = new Schema({..}, { autoIndex: false });
+const Clock = mongoose.model('Clock', schema);
+Clock.ensureIndexes(callback);
+```
+
+The `autoIndex` option is set to `true` by default. You can change this
+default by setting [`mongoose.set('autoIndex', false);`](/docs/api/mongoose.html#mongoose_Mongoose-set)
+
+<h3 id="autoCreate"><a href="#autoCreate">option: autoCreate</a></h3>
+
+Before Mongoose builds indexes, it calls `Model.createCollection()`
+to create the underlying collection in MongoDB if `autoCreate` is set to true.
+Calling `createCollection()`
+sets the [collection's default collation](https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations)
+based on the [collation option](#collation) and establishes the collection as
+a capped collection if you set the [`capped` schema option](#capped). Like
+`autoIndex`, setting `autoCreate` to true is helpful for development and
+test environments.
+
+Unfortunately, `createCollection()` cannot change an existing collection.
+For example, if you add `capped: 1024` to your schema and the existing
+collection is not capped, `createCollection()` will throw an error.
+Generally, `autoCreate` should be `false` for production environments.
+
+```javascript
+const schema = new Schema({..}, { autoCreate: true, capped: 1024 });
+const Clock = mongoose.model('Clock', schema);
+// Mongoose will create the capped collection for you.
+```
+
+Unlike `autoIndex`, `autoCreate` is `false` by default. You can change this
+default by setting [`mongoose.set('autoCreate', true);`](/docs/api/mongoose.html#mongoose_Mongoose-set)
+
+<h3 id="bufferCommands"><a href="#bufferCommands">option: bufferCommands</a></h3>
+
+By default, mongoose buffers commands when the connection goes down until
+the driver manages to reconnect. To disable buffering, set `bufferCommands`
+to false.
+
+```javascript
+const schema = new Schema({..}, { bufferCommands: false });
+```
+
+The schema `bufferCommands` option overrides the global `bufferCommands` option.
+
+```javascript
+mongoose.set('bufferCommands', true);
+// Schema option below overrides the above, if the schema option is set.
+const schema = new Schema({..}, { bufferCommands: false });
+```
+
+<h3 id="bufferTimeoutMS"><a href="#bufferTimeoutMS">option: bufferTimeoutMS</a></h3>
+
+If `bufferCommands` is on, this option sets the maximum amount of time Mongoose buffering will wait before
+throwing an error. If not specified, Mongoose will use 10000 (10 seconds).
+
+```javascript
+// If an operation is buffered for more than 1 second, throw an error.
+const schema = new Schema({..}, { bufferTimeoutMS: 1000 });
+```
+
+<h3 id="capped"><a href="#capped">option: capped</a></h3>
+
+Mongoose supports MongoDBs [capped](http://www.mongodb.org/display/DOCS/Capped+Collections)
+collections. To specify the underlying MongoDB collection be `capped`, set
+the `capped` option to the maximum size of the collection in
+[bytes](http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-size.).
+
+```javascript
+new Schema({..}, { capped: 1024 });
+```
+
+The `capped` option may also be set to an object if you want to pass
+additional options like [max](http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-max)
+or [autoIndexId](http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-autoIndexId).
+In this case you must explicitly pass the `size` option, which is required.
+
+```javascript
+new Schema({..}, { capped: { size: 1024, max: 1000, autoIndexId: true } });
+```
+
+<h3 id="collection"><a href="#collection">option: collection</a></h3>
+
+Mongoose by default produces a collection name by passing the model name to
+the [utils.toCollectionName](./api.html#utils_exports.toCollectionName) method.
+This method pluralizes the name. Set this option if you need a different name
+for your collection.
+
+```javascript
+const dataSchema = new Schema({..}, { collection: 'data' });
+```
+
+<h3 id="discriminatorKey"><a href="#discriminatorKey">option: discriminatorKey</a></h3>
+
+When you define a [discriminator](/docs/discriminators.html), Mongoose adds a path to your
+schema that stores which discriminator a document is an instance of. By default, Mongoose
+adds an `__t` path, but you can set `discriminatorKey` to overwrite this default.
+
+```javascript
+const baseSchema = new Schema({}, { discriminatorKey: 'type' });
+const BaseModel = mongoose.model('Test', baseSchema);
+
+const personSchema = new Schema({ name: String });
+const PersonModel = BaseModel.discriminator('Person', personSchema);
+
+const doc = new PersonModel({ name: 'James T. Kirk' });
+// Without `discriminatorKey`, Mongoose would store the discriminator
+// key in `__t` instead of `type`
+doc.type; // 'Person'
+```
+
+<h3 id="id"><a href="#id">option: id</a></h3>
+
+Mongoose assigns each of your schemas an `id` virtual getter by default
+which returns the document's `_id` field cast to a string, or in the case of
+ObjectIds, its hexString. If you don't want an `id` getter added to your
+schema, you may disable it by passing this option at schema construction time.
+
+```javascript
+// default behavior
+const schema = new Schema({ name: String });
+const Page = mongoose.model('Page', schema);
+const p = new Page({ name: 'mongodb.org' });
+console.log(p.id); // '50341373e894ad16347efe01'
+
+// disabled id
+const schema = new Schema({ name: String }, { id: false });
+const Page = mongoose.model('Page', schema);
+const p = new Page({ name: 'mongodb.org' });
+console.log(p.id); // undefined
+```
+
+<h3 id="_id"><a href="#_id">option: _id</a></h3>
+
+Mongoose assigns each of your schemas an `_id` field by default if one
+is not passed into the [Schema](/docs/api.html#schema-js) constructor.
+The type assigned is an [ObjectId](/docs/api.html#schema_Schema.Types)
+to coincide with MongoDB's default behavior. If you don't want an `_id`
+added to your schema at all, you may disable it using this option.
+
+You can **only** use this option on subdocuments. Mongoose can't
+save a document without knowing its id, so you will get an error if
+you try to save a document without an `_id`.
+
+```javascript
+// default behavior
+const schema = new Schema({ name: String });
+const Page = mongoose.model('Page', schema);
+const p = new Page({ name: 'mongodb.org' });
+console.log(p); // { _id: '50341373e894ad16347efe01', name: 'mongodb.org' }
+
+// disabled _id
+const childSchema = new Schema({ name: String }, { _id: false });
+const parentSchema = new Schema({ children: [childSchema] });
+
+const Model = mongoose.model('Model', parentSchema);
+
+Model.create({ children: [{ name: 'Luke' }] }, (error, doc) => {
+  // doc.children[0]._id will be undefined
+});
+```
+
+<h3 id="minimize"><a href="#minimize">option: minimize</a></h3>
+
+Mongoose will, by default, "minimize" schemas by removing empty objects.
+
+```javascript
+const schema = new Schema({ name: String, inventory: {} });
+const Character = mongoose.model('Character', schema);
+
+// will store `inventory` field if it is not empty
+const frodo = new Character({ name: 'Frodo', inventory: { ringOfPower: 1 }});
+await frodo.save();
+let doc = await Character.findOne({ name: 'Frodo' }).lean();
+doc.inventory; // { ringOfPower: 1 }
+
+// will not store `inventory` field if it is empty
+const sam = new Character({ name: 'Sam', inventory: {}});
+await sam.save();
+doc = await Character.findOne({ name: 'Sam' }).lean();
+doc.inventory; // undefined
+```
+
+This behavior can be overridden by setting `minimize` option to `false`. It
+will then store empty objects.
+
+```javascript
+const schema = new Schema({ name: String, inventory: {} }, { minimize: false });
+const Character = mongoose.model('Character', schema);
+
+// will store `inventory` if empty
+const sam = new Character({ name: 'Sam', inventory: {} });
+await sam.save();
+doc = await Character.findOne({ name: 'Sam' }).lean();
+doc.inventory; // {}
+```
+
+To check whether an object is empty, you can use the `$isEmpty()` helper:
+
+```javascript
+const sam = new Character({ name: 'Sam', inventory: {} });
+sam.$isEmpty('inventory'); // true
+
+sam.inventory.barrowBlade = 1;
+sam.$isEmpty('inventory'); // false
+```
+
+<h3 id="read"><a href="#read">option: read</a></h3>
+
+Allows setting [query#read](/docs/api.html#query_Query-read) options at the
+schema level, providing us a way to apply default
+[ReadPreferences](http://docs.mongodb.org/manual/applications/replication/#replica-set-read-preference)
+to all queries derived from a model.
+
+```javascript
+const schema = new Schema({..}, { read: 'primary' });            // also aliased as 'p'
+const schema = new Schema({..}, { read: 'primaryPreferred' });   // aliased as 'pp'
+const schema = new Schema({..}, { read: 'secondary' });          // aliased as 's'
+const schema = new Schema({..}, { read: 'secondaryPreferred' }); // aliased as 'sp'
+const schema = new Schema({..}, { read: 'nearest' });            // aliased as 'n'
+```
+
+The alias of each pref is also permitted so instead of having to type out
+'secondaryPreferred' and getting the spelling wrong, we can simply pass 'sp'.
+
+The read option also allows us to specify _tag sets_. These tell the
+[driver](https://github.com/mongodb/node-mongodb-native/) from which members
+of the replica-set it should attempt to read. Read more about tag sets
+[here](http://docs.mongodb.org/manual/applications/replication/#tag-sets) and
+[here](http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences).
+
+_NOTE: you may also specify the driver read pref [strategy](http://mongodb.github.com/node-mongodb-native/api-generated/replset.html?highlight=strategy)
+option when connecting:_
+
+```javascript
+// pings the replset members periodically to track network latency
+const options = { replset: { strategy: 'ping' }};
+mongoose.connect(uri, options);
+
+const schema = new Schema({..}, { read: ['nearest', { disk: 'ssd' }] });
+mongoose.model('JellyBean', schema);
+```
+
+<h3 id="writeConcern"><a href="#writeConcern">option: writeConcern</a></h3>
+
+Allows setting [write concern](https://docs.mongodb.com/manual/reference/write-concern/)
+at the schema level.
+
+```javascript
+const schema = new Schema({ name: String }, {
+  writeConcern: {
+    w: 'majority',
+    j: true,
+    wtimeout: 1000
+  }
+});
+```
+
+<h3 id="shardKey"><a href="#shardKey">option: shardKey</a></h3>
+
+The `shardKey` option is used when we have a [sharded MongoDB architecture](http://www.mongodb.org/display/DOCS/Sharding+Introduction).
+Each sharded collection is given a shard key which must be present in all
+insert/update operations. We just need to set this schema option to the same
+shard key and we’ll be all set.
+
+```javascript
+new Schema({ .. }, { shardKey: { tag: 1, name: 1 }})
+```
+
+_Note that Mongoose does not send the `shardcollection` command for you. You
+must configure your shards yourself._
+
+<h3 id="strict"><a href="#strict">option: strict</a></h3>
+
+The strict option, (enabled by default), ensures that values passed to our
+model constructor that were not specified in our schema do not get saved to
+the db.
+
+```javascript
+const thingSchema = new Schema({..})
+const Thing = mongoose.model('Thing', thingSchema);
+const thing = new Thing({ iAmNotInTheSchema: true });
+thing.save(); // iAmNotInTheSchema is not saved to the db
+
+// set to false..
+const thingSchema = new Schema({..}, { strict: false });
+const thing = new Thing({ iAmNotInTheSchema: true });
+thing.save(); // iAmNotInTheSchema is now saved to the db!!
+```
+
+This also affects the use of `doc.set()` to set a property value.
+
+```javascript
+const thingSchema = new Schema({..})
+const Thing = mongoose.model('Thing', thingSchema);
+const thing = new Thing;
+thing.set('iAmNotInTheSchema', true);
+thing.save(); // iAmNotInTheSchema is not saved to the db
+```
+
+This value can be overridden at the model instance level by passing a second
+boolean argument:
+
+```javascript
+const Thing = mongoose.model('Thing');
+const thing = new Thing(doc, true);  // enables strict mode
+const thing = new Thing(doc, false); // disables strict mode
+```
+
+The `strict` option may also be set to `"throw"` which will cause errors
+to be produced instead of dropping the bad data.
+
+_NOTE: Any key/val set on the instance that does not exist in your schema
+is always ignored, regardless of schema option._
+
+```javascript
+const thingSchema = new Schema({..})
+const Thing = mongoose.model('Thing', thingSchema);
+const thing = new Thing;
+thing.iAmNotInTheSchema = true;
+thing.save(); // iAmNotInTheSchema is never saved to the db
+```
+
+<h3 id="strictQuery"><a href="#strictQuery">option: strictQuery</a></h3>
+
+For backwards compatibility, the `strict` option does **not** apply to
+the `filter` parameter for queries.
+
+```javascript
+const mySchema = new Schema({ field: Number }, { strict: true });
+const MyModel = mongoose.model('Test', mySchema);
+
+// Mongoose will **not** filter out `notInSchema: 1`, despite `strict: true`
+MyModel.find({ notInSchema: 1 });
+```
+
+The `strict` option does apply to updates.
+
+```javascript
+// Mongoose will strip out `notInSchema` from the update if `strict` is
+// not `false`
+MyModel.updateMany({}, { $set: { notInSchema: 1 } });
+```
+
+Mongoose has a separate `strictQuery` option to toggle strict mode for
+the `filter` parameter to queries.
+
+```javascript
+const mySchema = new Schema({ field: Number }, {
+  strict: true,
+  strictQuery: true // Turn on strict mode for query filters
+});
+const MyModel = mongoose.model('Test', mySchema);
+
+// Mongoose will strip out `notInSchema: 1` because `strictQuery` is `true`
+MyModel.find({ notInSchema: 1 });
+```
+
+<h3 id="toJSON"><a href="#toJSON">option: toJSON</a></h3>
+
+Exactly the same as the [toObject](#toObject) option but only applies when
+the document's [`toJSON` method](https://thecodebarbarian.com/what-is-the-tojson-function-in-javascript.html) is called.
+
+```javascript
+const schema = new Schema({ name: String });
+schema.path('name').get(function (v) {
+  return v + ' is my name';
+});
+schema.set('toJSON', { getters: true, virtuals: false });
+const M = mongoose.model('Person', schema);
+const m = new M({ name: 'Max Headroom' });
+console.log(m.toObject()); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom' }
+console.log(m.toJSON()); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }
+// since we know toJSON is called whenever a js object is stringified:
+console.log(JSON.stringify(m)); // { "_id": "504e0cd7dd992d9be2f20b6f", "name": "Max Headroom is my name" }
+```
+
+To see all available `toJSON/toObject` options, read [this](/docs/api.html#document_Document-toObject).
+
+<h3 id="toObject"><a href="#toObject">option: toObject</a></h3>
+
+Documents have a [toObject](/docs/api.html#document_Document-toObject) method
+which converts the mongoose document into a plain JavaScript object. This
+method accepts a few options. Instead of applying these options on a
+per-document basis, we may declare the options at the schema level and have
+them applied to all of the schema's documents by default.
+
+To have all virtuals show up in your `console.log` output, set the
+`toObject` option to `{ getters: true }`:
+
+```javascript
+const schema = new Schema({ name: String });
+schema.path('name').get(function(v) {
+  return v + ' is my name';
+});
+schema.set('toObject', { getters: true });
+const M = mongoose.model('Person', schema);
+const m = new M({ name: 'Max Headroom' });
+console.log(m); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }
+```
+
+To see all available `toObject` options, read [this](/docs/api.html#document_Document-toObject).
+
+<h3 id="typeKey"><a href="#typeKey">option: typeKey</a></h3>
+
+By default, if you have an object with key 'type' in your schema, mongoose
+will interpret it as a type declaration.
+
+```javascript
+// Mongoose interprets this as 'loc is a String'
+const schema = new Schema({ loc: { type: String, coordinates: [Number] } });
+```
+
+However, for applications like [geoJSON](http://docs.mongodb.org/manual/reference/geojson/),
+the 'type' property is important. If you want to control which key mongoose
+uses to find type declarations, set the 'typeKey' schema option.
+
+```javascript
+const schema = new Schema({
+  // Mongoose interpets this as 'loc is an object with 2 keys, type and coordinates'
+  loc: { type: String, coordinates: [Number] },
+  // Mongoose interprets this as 'name is a String'
+  name: { $type: String }
+}, { typeKey: '$type' }); // A '$type' key means this object is a type declaration
+```
+
+<h3 id="validateBeforeSave"><a href="#validateBeforeSave">option: validateBeforeSave</a></h3>
+
+By default, documents are automatically validated before they are saved to
+the database. This is to prevent saving an invalid document. If you want to
+handle validation manually, and be able to save objects which don't pass
+validation, you can set `validateBeforeSave` to false.
+
+```javascript
+const schema = new Schema({ name: String });
+schema.set('validateBeforeSave', false);
+schema.path('name').validate(function (value) {
+    return value != null;
+});
+const M = mongoose.model('Person', schema);
+const m = new M({ name: null });
+m.validate(function(err) {
+    console.log(err); // Will tell you that null is not allowed.
+});
+m.save(); // Succeeds despite being invalid
+```
+
+<h3 id="versionKey"><a href="#versionKey">option: versionKey</a></h3>
+
+The `versionKey` is a property set on each document when first created by
+Mongoose. This keys value contains the internal
+[revision](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)
+of the document. The `versionKey` option is a string that represents the
+path to use for versioning. The default is `__v`. If this conflicts with
+your application you can configure as such:
+
+```javascript
+const schema = new Schema({ name: 'string' });
+const Thing = mongoose.model('Thing', schema);
+const thing = new Thing({ name: 'mongoose v3' });
+await thing.save(); // { __v: 0, name: 'mongoose v3' }
+
+// customized versionKey
+new Schema({..}, { versionKey: '_somethingElse' })
+const Thing = mongoose.model('Thing', schema);
+const thing = new Thing({ name: 'mongoose v3' });
+thing.save(); // { _somethingElse: 0, name: 'mongoose v3' }
+```
+
+Note that Mongoose's default versioning is **not** a full [optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control)
+solution. Mongoose's default versioning only operates on arrays as shown below.
+
+```javascript
+// 2 copies of the same document
+const doc1 = await Model.findOne({ _id });
+const doc2 = await Model.findOne({ _id });
+
+// Delete first 3 comments from `doc1`
+doc1.comments.splice(0, 3);
+await doc1.save();
+
+// The below `save()` will throw a VersionError, because you're trying to
+// modify the comment at index 1, and the above `splice()` removed that
+// comment.
+doc2.set('comments.1.body', 'new comment');
+await doc2.save();
+```
+
+If you need optimistic concurrency support for `save()`, you can set the [`optimisticConcurrency` option](#optimisticConcurrency)
+
+Document versioning can also be disabled by setting the `versionKey` to
+`false`.
+_DO NOT disable versioning unless you [know what you are doing](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)._
+
+```javascript
+new Schema({..}, { versionKey: false });
+const Thing = mongoose.model('Thing', schema);
+const thing = new Thing({ name: 'no versioning please' });
+thing.save(); // { name: 'no versioning please' }
+```
+
+Mongoose _only_ updates the version key when you use [`save()`](/docs/api.html#document_Document-save).
+If you use `update()`, `findOneAndUpdate()`, etc. Mongoose will **not**
+update the version key. As a workaround, you can use the below middleware.
+
+```javascript
+schema.pre('findOneAndUpdate', function() {
+  const update = this.getUpdate();
+  if (update.__v != null) {
+    delete update.__v;
+  }
+  const keys = ['$set', '$setOnInsert'];
+  for (const key of keys) {
+    if (update[key] != null && update[key].__v != null) {
+      delete update[key].__v;
+      if (Object.keys(update[key]).length === 0) {
+        delete update[key];
+      }
+    }
+  }
+  update.$inc = update.$inc || {};
+  update.$inc.__v = 1;
+});
+```
+
+<h3 id="optimisticConcurrency"><a href="#optimisticConcurrency">option: optimisticConcurrency</a></h3>
+
+[Optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control) is a strategy to ensure
+the document you're updating didn't change between when you loaded it using `find()` or `findOne()`, and when
+you update it using `save()`.
+
+For example, suppose you have a `House` model that contains a list of `photos`, and a `status` that represents
+whether this house shows up in searches. Suppose that a house that has status `'APPROVED'` must have at least
+two `photos`. You might implement the logic of approving a house document as shown below:
+
+```javascript
+async function markApproved(id) {
+  const house = await House.findOne({ _id });
+  if (house.photos.length < 2) {
+    throw new Error('House must have at least two photos!');
+  }
+  
+  house.status = 'APPROVED';
+  await house.save();
+}
+```
+
+The `markApproved()` function looks right in isolation, but there might be a potential issue: what if another
+function removes the house's photos between the `findOne()` call and the `save()` call? For example, the below
+code will succeed:
+
+```javascript
+const house = await House.findOne({ _id });
+if (house.photos.length < 2) {
+  throw new Error('House must have at least two photos!');
+}
+
+const house2 = await House.findOne({ _id });
+house2.photos = [];
+await house2.save();
+
+// Marks the house as 'APPROVED' even though it has 0 photos!
+house.status = 'APPROVED';
+await house.save();
+```
+
+If you set the `optimisticConcurrency` option on the `House` model's schema, the above script will throw an
+error.
+
+```javascript
+const House = mongoose.model('House', Schema({
+  status: String,
+  photos: [String]
+}, { optimisticConcurrency: true }));
+
+const house = await House.findOne({ _id });
+if (house.photos.length < 2) {
+  throw new Error('House must have at least two photos!');
+}
+
+const house2 = await House.findOne({ _id });
+house2.photos = [];
+await house2.save();
+
+// Throws 'VersionError: No matching document found for id "..." version 0'
+house.status = 'APPROVED';
+await house.save();
+```
+
+<h3 id="collation"><a href="#collation">option: collation</a></h3>
+
+Sets a default [collation](https://docs.mongodb.com/manual/reference/collation/)
+for every query and aggregation. [Here's a beginner-friendly overview of collations](http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations).
+
+```javascript
+const schema = new Schema({
+  name: String
+}, { collation: { locale: 'en_US', strength: 1 } });
+
+const MyModel = db.model('MyModel', schema);
+
+MyModel.create([{ name: 'val' }, { name: 'Val' }]).
+  then(() => {
+    return MyModel.find({ name: 'val' });
+  }).
+  then((docs) => {
+    // `docs` will contain both docs, because `strength: 1` means
+    // MongoDB will ignore case when matching.
+  });
+```
+
+<h3 id="skipVersioning"><a href="#skipVersioning">option: skipVersioning</a></h3>
+
+`skipVersioning` allows excluding paths from versioning (i.e., the internal
+revision will not be incremented even if these paths are updated). DO NOT
+do this unless you know what you're doing. For subdocuments, include this
+on the parent document using the fully qualified path.
+
+```javascript
+new Schema({..}, { skipVersioning: { dontVersionMe: true } });
+thing.dontVersionMe.push('hey');
+thing.save(); // version is not incremented
+```
+
+<h3 id="timestamps"><a href="#timestamps">option: timestamps</a></h3>
+
+The `timestamps` option tells mongoose to assign `createdAt` and `updatedAt` fields
+to your schema. The type assigned is [Date](./api.html#schema-date-js).
+
+By default, the names of the fields are `createdAt` and `updatedAt`. Customize
+the field names by setting `timestamps.createdAt` and `timestamps.updatedAt`.
+
+```javascript
+const thingSchema = new Schema({..}, { timestamps: { createdAt: 'created_at' } });
+const Thing = mongoose.model('Thing', thingSchema);
+const thing = new Thing();
+await thing.save(); // `created_at` & `updatedAt` will be included
+
+// With updates, Mongoose will add `updatedAt` to `$set`
+await Thing.updateOne({}, { $set: { name: 'Test' } });
+
+// If you set upsert: true, Mongoose will add `created_at` to `$setOnInsert` as well
+await Thing.findOneAndUpdate({}, { $set: { name: 'Test2' } });
+
+// Mongoose also adds timestamps to bulkWrite() operations
+// See https://mongoosejs.com/docs/api.html#model_Model.bulkWrite
+await Thing.bulkWrite([
+  insertOne: {
+    document: {
+      name: 'Jean-Luc Picard',
+      ship: 'USS Stargazer'
+      // Mongoose will add `created_at` and `updatedAt`
+    }
+  },
+  updateOne: {
+    filter: { name: 'Jean-Luc Picard' },
+    update: {
+      $set: {
+        ship: 'USS Enterprise'
+        // Mongoose will add `updatedAt`
+      }
+    }
+  }
+]);
+```
+
+By default, Mongoose uses `new Date()` to get the current time.
+If you want to overwrite the function
+Mongoose uses to get the current time, you can set the
+`timestamps.currentTime` option. Mongoose will call the
+`timestamps.currentTime` function whenever it needs to get
+the current time.
+
+```javascript
+const schema = Schema({
+  createdAt: Number,
+  updatedAt: Number,
+  name: String
+}, {
+  // Make Mongoose use Unix time (seconds since Jan 1, 1970)
+  timestamps: { currentTime: () => Math.floor(Date.now() / 1000) }
+});
+```
+
+<h3 id="useNestedStrict"><a href="#useNestedStrict">option: useNestedStrict</a></h3>
+
+Write operations like `update()`, `updateOne()`, `updateMany()`,
+and `findOneAndUpdate()` only check the top-level
+schema's strict mode setting.
+
+```javascript
+const childSchema = new Schema({}, { strict: false });
+const parentSchema = new Schema({ child: childSchema }, { strict: 'throw' });
+const Parent = mongoose.model('Parent', parentSchema);
+Parent.update({}, { 'child.name': 'Luke Skywalker' }, (error) => {
+  // Error because parentSchema has `strict: throw`, even though
+  // `childSchema` has `strict: false`
+});
+
+const update = { 'child.name': 'Luke Skywalker' };
+const opts = { strict: false };
+Parent.update({}, update, opts, function(error) {
+  // This works because passing `strict: false` to `update()` overwrites
+  // the parent schema.
+});
+```
+
+If you set `useNestedStrict` to true, mongoose will use the child schema's
+`strict` option for casting updates.
+
+```javascript
+const childSchema = new Schema({}, { strict: false });
+const parentSchema = new Schema({ child: childSchema },
+  { strict: 'throw', useNestedStrict: true });
+const Parent = mongoose.model('Parent', parentSchema);
+Parent.update({}, { 'child.name': 'Luke Skywalker' }, error => {
+  // Works!
+});
+```
+
+<h3 id="selectPopulatedPaths">
+  <a href="#selectPopulatedPaths">
+    option: selectPopulatedPaths
+  </a>
+</h3>
+
+By default, Mongoose will automatically `select()` any populated paths for
+you, unless you explicitly exclude them.
+
+```javascript
+const bookSchema = new Schema({
+  title: 'String',
+  author: { type: 'ObjectId', ref: 'Person' }
+});
+const Book = mongoose.model('Book', bookSchema);
+
+// By default, Mongoose will add `author` to the below `select()`.
+await Book.find().select('title').populate('author');
+
+// In other words, the below query is equivalent to the above
+await Book.find().select('title author').populate('author');
+```
+
+To opt out of selecting populated fields by default, set `selectPopulatedPaths`
+to `false` in your schema.
+
+```javascript
+const bookSchema = new Schema({
+  title: 'String',
+  author: { type: 'ObjectId', ref: 'Person' }
+}, { selectPopulatedPaths: false });
+const Book = mongoose.model('Book', bookSchema);
+
+// Because `selectPopulatedPaths` is false, the below doc will **not**
+// contain an `author` property.
+const doc = await Book.findOne().select('title').populate('author');
+```
+
+<h3 id="storeSubdocValidationError">
+  <a href="#storeSubdocValidationError">
+    option: storeSubdocValidationError
+  </a>
+</h3>
+
+For legacy reasons, when there is a validation error in subpath of a
+single nested schema, Mongoose will record that there was a validation error
+in the single nested schema path as well. For example:
+
+```javascript
+const childSchema = new Schema({ name: { type: String, required: true } });
+const parentSchema = new Schema({ child: childSchema });
+
+const Parent = mongoose.model('Parent', parentSchema);
+
+// Will contain an error for both 'child.name' _and_ 'child'
+new Parent({ child: {} }).validateSync().errors;
+```
+
+Set the `storeSubdocValidationError` to `false` on the child schema to make
+Mongoose only reports the parent error.
+
+```javascript
+const childSchema = new Schema({
+  name: { type: String, required: true }
+}, { storeSubdocValidationError: false }); // <-- set on the child schema
+const parentSchema = new Schema({ child: childSchema });
+
+const Parent = mongoose.model('Parent', parentSchema);
+
+// Will only contain an error for 'child.name'
+new Parent({ child: {} }).validateSync().errors;
+```
+
+<h3 id="es6-classes"><a href="#es6-classes">With ES6 Classes</a></h3>
+
+Schemas have a [`loadClass()` method](/docs/api/schema.html#schema_Schema-loadClass)
+that you can use to create a Mongoose schema from an [ES6 class](https://thecodebarbarian.com/an-overview-of-es6-classes):
+
+* [ES6 class methods](https://masteringjs.io/tutorials/fundamentals/class#methods) become [Mongoose methods](/docs/guide.html#methods)
+* [ES6 class statics](https://masteringjs.io/tutorials/fundamentals/class#statics) become [Mongoose statics](/docs/guide.html#statics)
+* [ES6 getters and setters](https://masteringjs.io/tutorials/fundamentals/class#getterssetters) become [Mongoose virtuals](/docs/tutorials/virtuals.html)
+
+Here's an example of using `loadClass()` to create a schema from an ES6 class:
+
+```javascript
+class MyClass {
+  myMethod() { return 42; }
+  static myStatic() { return 42; }
+  get myVirtual() { return 42; }
+}
+
+const schema = new mongoose.Schema();
+schema.loadClass(MyClass);
+
+console.log(schema.methods); // { myMethod: [Function: myMethod] }
+console.log(schema.statics); // { myStatic: [Function: myStatic] }
+console.log(schema.virtuals); // { myVirtual: VirtualType { ... } }
+```
+
+<h3 id="plugins"><a href="#plugins">Pluggable</a></h3>
+
+Schemas are also [pluggable](./plugins.html) which allows us to package up reusable features into
+plugins that can be shared with the community or just between your projects.
+
+<h3 id="further-reading">Further Reading</h3>
+
+Here's an [alternative introduction to Mongoose schemas](https://masteringjs.io/tutorials/mongoose/schema).
+
+To get the most out of MongoDB, you need to learn the basics of MongoDB schema design.
+SQL schema design (third normal form) was designed to [minimize storage costs](https://en.wikipedia.org/wiki/Third_normal_form),
+whereas MongoDB schema design is about making common queries as fast as possible.
+The [_6 Rules of Thumb for MongoDB Schema Design_ blog series](https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-1)
+is an excellent resource for learning the basic rules for making your queries
+fast.
+
+Users looking to master MongoDB schema design in Node.js should look into
+[_The Little MongoDB Schema Design Book_](http://bit.ly/mongodb-schema-design)
+by Christian Kvalheim, the original author of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb).
+This book shows you how to implement performant schemas for a laundry list
+of use cases, including e-commerce, wikis, and appointment bookings.
+
+<h3 id="next">Next Up</h3>
+
+Now that we've covered `Schemas`, let's take a look at [SchemaTypes](/docs/schematypes.html).
diff --git a/docs/guide.pug b/docs/guide.pug
deleted file mode 100644
index 7f26bddef99..00000000000
--- a/docs/guide.pug
+++ /dev/null
@@ -1,1304 +0,0 @@
-extends layout
-
-append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Schemas
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-  .important
-    :markdown
-      If you haven't yet done so, please take a minute to read the [quickstart](./index.html) to get an idea of how Mongoose works.
-      If you are migrating from 4.x to 5.x please take a moment to read the [migration guide](/docs/migrating_to_5.html).
-  :markdown
-    <ul class="toc">
-      <li><a href="#definition">Defining your schema</a></li>
-      <li><a href="#models">Creating a model</a></li>
-      <li><a href="#_id">Ids</a></li>
-      <li><a href="#methods">Instance methods</a></li>
-      <li><a href="#statics">Statics</a></li>
-      <li><a href="#query-helpers">Query Helpers</a></li>
-      <li><a href="#indexes">Indexes</a></li>
-      <li><a href="#virtuals">Virtuals</a></li>
-      <li><a href="#aliases">Aliases</a></li>
-      <li><a href="#options">Options</a></li>
-      <li><a href="#es6-classes">With ES6 Classes</a></li>
-      <li><a href="#plugins">Pluggable</a></li>
-      <li><a href="#further-reading">Further Reading</a></li>
-    </ul>
-
-    <h3 id="definition"><a href="#definition">Defining your schema</a></h3>
-
-    Everything in Mongoose starts with a Schema. Each schema maps to a MongoDB
-    collection and defines the shape of the documents within that collection.
-
-    ```javascript
-      import mongoose from 'mongoose';
-      const { Schema } = mongoose;
-
-      const blogSchema = new Schema({
-        title:  String, // String is shorthand for {type: String}
-        author: String,
-        body:   String,
-        comments: [{ body: String, date: Date }],
-        date: { type: Date, default: Date.now },
-        hidden: Boolean,
-        meta: {
-          votes: Number,
-          favs:  Number
-        }
-      });
-    ```
-
-    If you want to add additional keys later, use the
-    [Schema#add](./api.html#schema_Schema-add) method.
-
-    Each key in our code `blogSchema` defines a property in our documents which
-    will be cast to its associated [SchemaType](./api.html#schematype_SchemaType).
-    For example, we've defined a property `title` which will be cast to the
-    [String](./api.html#schema-string-js) SchemaType and property `date`
-    which will be cast to a `Date` SchemaType.
-
-    Notice above that if a property only requires a type, it can be specified using
-    a shorthand notation (contrast the `title` property above with the `date`
-    property).
-    
-    Keys may also be assigned nested objects containing further key/type definitions
-    like the `meta` property above.  This will happen whenever a key's value is a POJO
-    that doesn't have a `type` property.
-    
-    In these cases, Mongoose only creates actual schema paths for leaves
-    in the tree. (like `meta.votes` and `meta.favs` above),
-    and the branches do not have actual paths.  A side-effect of this is that `meta`
-    above cannot have its own validation.  If validation is needed up the tree, a path
-    needs to be created up the tree - see the [Subdocuments](./subdocs.html) section
-    for more information on how to do this.  Also read the [Mixed](./schematypes.html)
-    subsection of the SchemaTypes guide for some gotchas.
-
-    The permitted SchemaTypes are:
-
-    * [String](./schematypes.html#strings)
-    * [Number](./schematypes.html#numbers)
-    * [Date](./schematypes.html#dates)
-    * [Buffer](./schematypes.html#buffers)
-    * [Boolean](./schematypes.html#booleans)
-    * [Mixed](./schematypes.html#mixed)
-    * [ObjectId](./schematypes.html#objectids)
-    * [Array](./schematypes.html#arrays)
-    * [Decimal128](./api.html#mongoose_Mongoose-Decimal128)
-    * [Map](./schematypes.html#maps)
-
-    Read more about [SchemaTypes here](./schematypes.html).
-
-    Schemas not only define the structure of your document and casting of
-    properties, they also define document [instance methods](#methods),
-    [static Model methods](#statics), [compound indexes](#indexes),
-    and document lifecycle hooks called [middleware](./middleware.html).
-
-    <h3 id="models"><a href="#models">Creating a model</a></h3>
-
-    To use our schema definition, we need to convert our `blogSchema` into a
-    [Model](./models.html) we can work with.
-    To do so, we pass it into `mongoose.model(modelName, schema)`:
-
-    ```javascript
-      const Blog = mongoose.model('Blog', blogSchema);
-      // ready to go!
-    ```
-
-    <h3 id="_id"><a href="#_id">Ids</a></h3>
-
-    By default, Mongoose adds an `_id` property to your schemas.
-
-    ```javascript
-    const schema = new Schema();
-
-    schema.path('_id'); // ObjectId { ... }
-    ```
-
-    When you create a new document with the automatically added
-    `_id` property, Mongoose creates a new [`_id` of type ObjectId](https://masteringjs.io/tutorials/mongoose/objectid)
-    to your document.
-
-    ```javascript
-    const Model = mongoose.model('Test', schema);
-
-    const doc = new Model();
-    doc._id instanceof mongoose.Types.ObjectId; // true
-    ```
-
-    You can also overwrite Mongoose's default `_id` with your
-    own `_id`. Just be careful: Mongoose will refuse to save a
-    document that doesn't have an `_id`, so you're responsible
-    for setting `_id` if you define your own `_id` path.
-
-    ```javascript
-    const schema = new Schema({ _id: Number });
-    const Model = mongoose.model('Test', schema);
-
-    const doc = new Model();
-    await doc.save(); // Throws "document must have an _id before saving"
-    
-    doc._id = 1;
-    await doc.save(); // works
-    ```
-
-    <h3 id="methods"><a href="#methods">Instance methods</a></h3>
-
-    Instances of `Models` are [documents](./documents.html). Documents have
-    many of their own [built-in instance methods](./api/document.html).
-    We may also define our own custom document instance methods.
-
-    ```javascript
-      // define a schema
-      const animalSchema = new Schema({ name: String, type: String });
-
-      // assign a function to the "methods" object of our animalSchema
-      animalSchema.methods.findSimilarTypes = function(cb) {
-        return mongoose.model('Animal').find({ type: this.type }, cb);
-      };
-    ```
-
-    Now all of our `animal` instances have a `findSimilarTypes` method available
-    to them.
-
-    ```javascript
-      const Animal = mongoose.model('Animal', animalSchema);
-      const dog = new Animal({ type: 'dog' });
-
-      dog.findSimilarTypes((err, dogs) => {
-        console.log(dogs); // woof
-      });
-    ```
-
-    * Overwriting a default mongoose document method may lead to unpredictable results. See [this](./api.html#schema_Schema.reserved) for more details.
-    * The example above uses the `Schema.methods` object directly to save an instance method. You can also use the `Schema.method()` helper as described [here](./api.html#schema_Schema-method).
-    * Do **not** declare methods using ES6 arrow functions (`=>`). Arrow functions [explicitly prevent binding `this`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this), so your method will **not** have access to the document and the above examples will not work.
-
-    <h3 id="statics"><a href="#statics">Statics</a></h3>
-
-    You can also add static functions to your model. There are two equivalent
-    ways to add a static:
-
-    - Add a function property to `schema.statics`
-    - Call the [`Schema#static()` function](/docs/api.html#schema_Schema-static)
-
-    ```javascript
-      // Assign a function to the "statics" object of our animalSchema
-      animalSchema.statics.findByName = function(name) {
-        return this.find({ name: new RegExp(name, 'i') });
-      };
-      // Or, equivalently, you can call `animalSchema.static()`.
-      animalSchema.static('findByBreed', function(breed) { return this.find({ breed }); });
-
-      const Animal = mongoose.model('Animal', animalSchema);
-      let animals = await Animal.findByName('fido');
-      animals = animals.concat(await Animal.findByBreed('Poodle'));
-    ```
-
-    Do **not** declare statics using ES6 arrow functions (`=>`). Arrow functions [explicitly prevent binding `this`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions#No_binding_of_this), so the above examples will not work because of the value of `this`.
-
-    <h3 id="query-helpers"><a href="#query-helpers">Query Helpers</a></h3>
-
-    You can also add query helper functions, which are like instance methods
-    but for mongoose queries. Query helper methods let you extend mongoose's
-    [chainable query builder API](./queries.html).
-
-    ```javascript
-      animalSchema.query.byName = function(name) {
-        return this.where({ name: new RegExp(name, 'i') })
-      };
-
-      const Animal = mongoose.model('Animal', animalSchema);
-
-      Animal.find().byName('fido').exec((err, animals) => {
-        console.log(animals);
-      });
-
-      Animal.findOne().byName('fido').exec((err, animal) => {
-        console.log(animal);
-      });
-    ```
-
-    <h3 id="indexes"><a href="#indexes">Indexes</a></h3>
-
-    MongoDB supports [secondary indexes](http://docs.mongodb.org/manual/indexes/).
-    With mongoose, we define these indexes within our `Schema` [at](./api.html#schematype_SchemaType-index) [the](./api.html#schematype_SchemaType-unique) [path](./api.html#schematype_SchemaType-sparse) [level](./api.html#schema_date_SchemaDate-expires) or the `schema` level.
-    Defining indexes at the schema level is necessary when creating
-    [compound indexes](https://docs.mongodb.com/manual/core/index-compound/).
-
-    ```javascript
-      const animalSchema = new Schema({
-        name: String,
-        type: String,
-        tags: { type: [String], index: true } // field level
-      });
-
-      animalSchema.index({ name: 1, type: -1 }); // schema level
-    ```
-
-    When your application starts up, Mongoose automatically calls [`createIndex`](https://docs.mongodb.com/manual/reference/method/db.collection.createIndex/#db.collection.createIndex) for each defined index in your schema.
-    Mongoose will call `createIndex` for each index sequentially, and emit an 'index' event on the model when all the `createIndex` calls succeeded or when there was an error.
-    While nice for development, it is recommended this behavior be disabled in production since index creation can cause a [significant performance impact](https://docs.mongodb.com/manual/core/index-creation/#index-build-impact-on-database-performance).
-    Disable the behavior by setting the `autoIndex` option of your schema to `false`, or globally on the connection by setting the option `autoIndex` to `false`.
-
-    ```javascript
-      mongoose.connect('mongodb://user:pass@localhost:port/database', { autoIndex: false });
-      // or
-      mongoose.createConnection('mongodb://user:pass@localhost:port/database', { autoIndex: false });
-      // or
-      animalSchema.set('autoIndex', false);
-      // or
-      new Schema({..}, { autoIndex: false });
-    ```
-
-    Mongoose will emit an `index` event on the model when indexes are done
-    building or an error occurred.
-
-    ```javascript
-      // Will cause an error because mongodb has an _id index by default that
-      // is not sparse
-      animalSchema.index({ _id: 1 }, { sparse: true });
-      const Animal = mongoose.model('Animal', animalSchema);
-
-      Animal.on('index', error => {
-        // "_id index cannot be sparse"
-        console.log(error.message);
-      });
-    ```
-
-    See also the [Model#ensureIndexes](./api.html#model_Model.ensureIndexes) method.
-
-    <h3 id="virtuals"><a href="#virtuals">Virtuals</a></h3>
-
-    [Virtuals](./api.html#schema_Schema-virtual) are document properties that
-    you can get and set but that do not get persisted to MongoDB. The getters
-    are useful for formatting or combining fields, while setters are useful for
-    de-composing a single value into multiple values for storage.
-
-    ```javascript
-      // define a schema
-      const personSchema = new Schema({
-        name: {
-          first: String,
-          last: String
-        }
-      });
-
-      // compile our model
-      const Person = mongoose.model('Person', personSchema);
-
-      // create a document
-      const axl = new Person({
-        name: { first: 'Axl', last: 'Rose' }
-      });
-    ```
-
-    Suppose you want to print out the person's full name. You could do it yourself:
-
-    ```javascript
-    console.log(axl.name.first + ' ' + axl.name.last); // Axl Rose
-    ```
-
-    But [concatenating](https://masteringjs.io/tutorials/fundamentals/string-concat) the first and
-    last name every time can get cumbersome.
-    And what if you want to do some extra processing on the name, like
-    [removing diacritics](https://www.npmjs.com/package/diacritics)? A
-    [virtual property getter](./api.html#virtualtype_VirtualType-get) lets you
-    define a `fullName` property that won't get persisted to MongoDB.
-
-    ```javascript
-    personSchema.virtual('fullName').get(function() {
-      return this.name.first + ' ' + this.name.last;
-    });
-    ```
-
-    Now, mongoose will call your getter function every time you access the
-    `fullName` property:
-
-    ```javascript
-    console.log(axl.fullName); // Axl Rose
-    ```
-
-    If you use `toJSON()` or `toObject()` mongoose will *not* include virtuals
-    by default. This includes the output of calling [`JSON.stringify()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify)
-    on a Mongoose document, because [`JSON.stringify()` calls `toJSON()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify#Description).
-    Pass `{ virtuals: true }` to either
-    [`toObject()`](./api.html#document_Document-toObject) or [`toJSON()`](./api.html#document_Document-toJSON).
-
-    You can also add a custom setter to your virtual that will let you set both
-    first name and last name via the `fullName` virtual.
-
-    ```javascript
-    personSchema.virtual('fullName').
-      get(function() {
-        return this.name.first + ' ' + this.name.last;
-       }).
-      set(function(v) {
-        this.name.first = v.substr(0, v.indexOf(' '));
-        this.name.last = v.substr(v.indexOf(' ') + 1);
-      });
-
-    axl.fullName = 'William Rose'; // Now `axl.name.first` is "William"
-    ```
-
-    Virtual property setters are applied before other validation. So the example
-    above would still work even if the `first` and `last` name fields were
-    required.
-
-    Only non-virtual properties work as part of queries and for field selection.
-    Since virtuals are not stored in MongoDB, you can't query with them.
-
-    You can [learn more about virtuals here](https://masteringjs.io/tutorials/mongoose/virtuals).
-
-    <h3 id="aliases"><a href="#aliases">Aliases</a></h3>
-
-    Aliases are a particular type of virtual where the getter and setter
-    seamlessly get and set another property. This is handy for saving network
-    bandwidth, so you can convert a short property name stored in the database
-    into a longer name for code readability.
-
-    ```javascript
-    const personSchema = new Schema({
-      n: {
-        type: String,
-        // Now accessing `name` will get you the value of `n`, and setting `name` will set the value of `n`
-        alias: 'name'
-      }
-    });
-
-    // Setting `name` will propagate to `n`
-    const person = new Person({ name: 'Val' });
-    console.log(person); // { n: 'Val' }
-    console.log(person.toObject({ virtuals: true })); // { n: 'Val', name: 'Val' }
-    console.log(person.name); // "Val"
-
-    person.name = 'Not Val';
-    console.log(person); // { n: 'Not Val' }
-    ```
-
-    You can also declare aliases on nested paths. It is easier to use nested
-    schemas and [subdocuments](/docs/subdocs.html), but you can also declare
-    nested path aliases inline as long as you use the full nested path
-    `nested.myProp` as the alias.
-
-    ```javascript
-    [require:gh-6671]
-    ```
-
-    <h3 id="options"><a href="#options">Options</a></h3>
-
-    Schemas have a few configurable options which can be passed to the
-    constructor or to the `set` method:
-
-    ```javascript
-    new Schema({..}, options);
-
-    // or
-
-    const schema = new Schema({..});
-    schema.set(option, value);
-    ```
-
-    Valid options:
-
-    - [autoIndex](#autoIndex)
-    - [autoCreate](#autoCreate)
-    - [bufferCommands](#bufferCommands)
-    - [bufferTimeoutMS](#bufferTimeoutMS)
-    - [capped](#capped)
-    - [collection](#collection)
-    - [discriminatorKey](#discriminatorKey)
-    - [id](#id)
-    - [_id](#_id)
-    - [minimize](#minimize)
-    - [read](#read)
-    - [writeConcern](#writeConcern)
-    - [shardKey](#shardKey)
-    - [strict](#strict)
-    - [strictQuery](#strictQuery)
-    - [toJSON](#toJSON)
-    - [toObject](#toObject)
-    - [typeKey](#typeKey)
-    - [typePojoToMixed](/docs/schematypes.html#mixed)
-    - [useNestedStrict](#useNestedStrict)
-    - [validateBeforeSave](#validateBeforeSave)
-    - [versionKey](#versionKey)
-    - [optimisticConcurrency](#optimisticConcurrency)
-    - [collation](#collation)
-    - [selectPopulatedPaths](#selectPopulatedPaths)
-    - [skipVersioning](#skipVersioning)
-    - [timestamps](#timestamps)
-    - [storeSubdocValidationError](#storeSubdocValidationError)
-
-    <h3 id="autoIndex"><a href="#autoIndex">option: autoIndex</a></h3>
-
-    By default, Mongoose's [`init()` function](/docs/api.html#model_Model.init)
-    creates all the indexes defined in your model's schema by calling
-    [`Model.createIndexes()`](/docs/api.html#model_Model.createIndexes)
-    after you successfully connect to MongoDB. Creating indexes automatically is
-    great for development and test environments. But index builds can also create
-    significant load on your production database. If you want to manage indexes
-    carefully in production, you can set `autoIndex` to false.
-
-    ```javascript
-    const schema = new Schema({..}, { autoIndex: false });
-    const Clock = mongoose.model('Clock', schema);
-    Clock.ensureIndexes(callback);
-    ```
-
-    The `autoIndex` option is set to `true` by default. You can change this
-    default by setting [`mongoose.set('autoIndex', false);`](/docs/api/mongoose.html#mongoose_Mongoose-set)
-
-    <h3 id="autoCreate"><a href="#autoCreate">option: autoCreate</a></h3>
-
-    Before Mongoose builds indexes, it calls `Model.createCollection()`
-    to create the underlying collection in MongoDB if `autoCreate` is set to true.
-    Calling `createCollection()`
-    sets the [collection's default collation](https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations)
-    based on the [collation option](#collation) and establishes the collection as
-    a capped collection if you set the [`capped` schema option](#capped). Like
-    `autoIndex`, setting `autoCreate` to true is helpful for development and
-    test environments.
-    
-    Unfortunately, `createCollection()` cannot change an existing collection.
-    For example, if you add `capped: 1024` to your schema and the existing
-    collection is not capped, `createCollection()` will throw an error.
-    Generally, `autoCreate` should be `false` for production environments.
-
-    ```javascript
-    const schema = new Schema({..}, { autoCreate: true, capped: 1024 });
-    const Clock = mongoose.model('Clock', schema);
-    // Mongoose will create the capped collection for you.
-    ```
-
-    Unlike `autoIndex`, `autoCreate` is `false` by default. You can change this
-    default by setting [`mongoose.set('autoCreate', true);`](/docs/api/mongoose.html#mongoose_Mongoose-set)
-
-    <h3 id="bufferCommands"><a href="#bufferCommands">option: bufferCommands</a></h3>
-
-    By default, mongoose buffers commands when the connection goes down until
-    the driver manages to reconnect. To disable buffering, set `bufferCommands`
-    to false.
-
-    ```javascript
-    const schema = new Schema({..}, { bufferCommands: false });
-    ```
-
-    The schema `bufferCommands` option overrides the global `bufferCommands` option.
-
-    ```javascript
-    mongoose.set('bufferCommands', true);
-    // Schema option below overrides the above, if the schema option is set.
-    const schema = new Schema({..}, { bufferCommands: false });
-    ```
-
-    <h3 id="bufferTimeoutMS"><a href="#bufferTimeoutMS">option: bufferTimeoutMS</a></h3>
-
-    If `bufferCommands` is on, this option sets the maximum amount of time Mongoose buffering will wait before
-    throwing an error. If not specified, Mongoose will use 10000 (10 seconds).
-
-    ```javascript
-    // If an operation is buffered for more than 1 second, throw an error.
-    const schema = new Schema({..}, { bufferTimeoutMS: 1000 });
-    ```
-
-    <h3 id="capped"><a href="#capped">option: capped</a></h3>
-
-    Mongoose supports MongoDBs [capped](http://www.mongodb.org/display/DOCS/Capped+Collections)
-    collections. To specify the underlying MongoDB collection be `capped`, set
-    the `capped` option to the maximum size of the collection in
-    [bytes](http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-size.).
-
-    ```javascript
-    new Schema({..}, { capped: 1024 });
-    ```
-
-    The `capped` option may also be set to an object if you want to pass
-    additional options like [max](http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-max)
-    or [autoIndexId](http://www.mongodb.org/display/DOCS/Capped+Collections#CappedCollections-autoIndexId).
-    In this case you must explicitly pass the `size` option, which is required.
-
-    ```javascript
-    new Schema({..}, { capped: { size: 1024, max: 1000, autoIndexId: true } });
-    ```
-
-    <h3 id="collection"><a href="#collection">option: collection</a></h3>
-
-    Mongoose by default produces a collection name by passing the model name to
-    the [utils.toCollectionName](./api.html#utils_exports.toCollectionName) method.
-    This method pluralizes the name. Set this option if you need a different name
-    for your collection.
-
-    ```javascript
-    const dataSchema = new Schema({..}, { collection: 'data' });
-    ```
-
-    <h3 id="discriminatorKey"><a href="#discriminatorKey">option: discriminatorKey</a></h3>
-
-    When you define a [discriminator](/docs/discriminators.html), Mongoose adds a path to your
-    schema that stores which discriminator a document is an instance of. By default, Mongoose
-    adds an `__t` path, but you can set `discriminatorKey` to overwrite this default.
-
-    ```javascript
-    const baseSchema = new Schema({}, { discriminatorKey: 'type' });
-    const BaseModel = mongoose.model('Test', baseSchema);
-
-    const personSchema = new Schema({ name: String });
-    const PersonModel = BaseModel.discriminator('Person', personSchema);
-
-    const doc = new PersonModel({ name: 'James T. Kirk' });
-    // Without `discriminatorKey`, Mongoose would store the discriminator
-    // key in `__t` instead of `type`
-    doc.type; // 'Person'
-    ```
-
-    <h3 id="id"><a href="#id">option: id</a></h3>
-
-    Mongoose assigns each of your schemas an `id` virtual getter by default
-    which returns the document's `_id` field cast to a string, or in the case of
-    ObjectIds, its hexString. If you don't want an `id` getter added to your
-    schema, you may disable it by passing this option at schema construction time.
-
-    ```javascript
-    // default behavior
-    const schema = new Schema({ name: String });
-    const Page = mongoose.model('Page', schema);
-    const p = new Page({ name: 'mongodb.org' });
-    console.log(p.id); // '50341373e894ad16347efe01'
-
-    // disabled id
-    const schema = new Schema({ name: String }, { id: false });
-    const Page = mongoose.model('Page', schema);
-    const p = new Page({ name: 'mongodb.org' });
-    console.log(p.id); // undefined
-    ```
-
-    <h3 id="_id"><a href="#_id">option: _id</a></h3>
-
-    Mongoose assigns each of your schemas an `_id` field by default if one
-    is not passed into the [Schema](/docs/api.html#schema-js) constructor.
-    The type assigned is an [ObjectId](/docs/api.html#schema_Schema.Types)
-    to coincide with MongoDB's default behavior. If you don't want an `_id`
-    added to your schema at all, you may disable it using this option.
-
-    You can **only** use this option on subdocuments. Mongoose can't
-    save a document without knowing its id, so you will get an error if
-    you try to save a document without an `_id`.
-
-    ```javascript
-    // default behavior
-    const schema = new Schema({ name: String });
-    const Page = mongoose.model('Page', schema);
-    const p = new Page({ name: 'mongodb.org' });
-    console.log(p); // { _id: '50341373e894ad16347efe01', name: 'mongodb.org' }
-
-    // disabled _id
-    const childSchema = new Schema({ name: String }, { _id: false });
-    const parentSchema = new Schema({ children: [childSchema] });
-
-    const Model = mongoose.model('Model', parentSchema);
-
-    Model.create({ children: [{ name: 'Luke' }] }, (error, doc) => {
-      // doc.children[0]._id will be undefined
-    });
-    ```
-
-    <h3 id="minimize"><a href="#minimize">option: minimize</a></h3>
-
-    Mongoose will, by default, "minimize" schemas by removing empty objects.
-
-    ```javascript
-    const schema = new Schema({ name: String, inventory: {} });
-    const Character = mongoose.model('Character', schema);
-
-    // will store `inventory` field if it is not empty
-    const frodo = new Character({ name: 'Frodo', inventory: { ringOfPower: 1 }});
-    await frodo.save();
-    let doc = await Character.findOne({ name: 'Frodo' }).lean();
-    doc.inventory; // { ringOfPower: 1 }
-
-    // will not store `inventory` field if it is empty
-    const sam = new Character({ name: 'Sam', inventory: {}});
-    await sam.save();
-    doc = await Character.findOne({ name: 'Sam' }).lean();
-    doc.inventory; // undefined
-    ```
-
-    This behavior can be overridden by setting `minimize` option to `false`. It
-    will then store empty objects.
-
-    ```javascript
-    const schema = new Schema({ name: String, inventory: {} }, { minimize: false });
-    const Character = mongoose.model('Character', schema);
-
-    // will store `inventory` if empty
-    const sam = new Character({ name: 'Sam', inventory: {} });
-    await sam.save();
-    doc = await Character.findOne({ name: 'Sam' }).lean();
-    doc.inventory; // {}
-    ```
-
-    To check whether an object is empty, you can use the `$isEmpty()` helper:
-
-    ```javascript
-    const sam = new Character({ name: 'Sam', inventory: {} });
-    sam.$isEmpty('inventory'); // true
-
-    sam.inventory.barrowBlade = 1;
-    sam.$isEmpty('inventory'); // false
-    ```
-
-    <h3 id="read"><a href="#read">option: read</a></h3>
-
-    Allows setting [query#read](/docs/api.html#query_Query-read) options at the
-    schema level, providing us a way to apply default
-    [ReadPreferences](http://docs.mongodb.org/manual/applications/replication/#replica-set-read-preference)
-    to all queries derived from a model.
-
-    ```javascript
-    const schema = new Schema({..}, { read: 'primary' });            // also aliased as 'p'
-    const schema = new Schema({..}, { read: 'primaryPreferred' });   // aliased as 'pp'
-    const schema = new Schema({..}, { read: 'secondary' });          // aliased as 's'
-    const schema = new Schema({..}, { read: 'secondaryPreferred' }); // aliased as 'sp'
-    const schema = new Schema({..}, { read: 'nearest' });            // aliased as 'n'
-    ```
-
-    The alias of each pref is also permitted so instead of having to type out
-    'secondaryPreferred' and getting the spelling wrong, we can simply pass 'sp'.
-
-    The read option also allows us to specify _tag sets_. These tell the
-    [driver](https://github.com/mongodb/node-mongodb-native/) from which members
-    of the replica-set it should attempt to read. Read more about tag sets
-    [here](http://docs.mongodb.org/manual/applications/replication/#tag-sets) and
-    [here](http://mongodb.github.com/node-mongodb-native/driver-articles/anintroductionto1_1and2_2.html#read-preferences).
-
-    _NOTE: you may also specify the driver read pref [strategy](http://mongodb.github.com/node-mongodb-native/api-generated/replset.html?highlight=strategy)
-    option when connecting:_
-
-    ```javascript
-    // pings the replset members periodically to track network latency
-    const options = { replset: { strategy: 'ping' }};
-    mongoose.connect(uri, options);
-
-    const schema = new Schema({..}, { read: ['nearest', { disk: 'ssd' }] });
-    mongoose.model('JellyBean', schema);
-    ```
-
-    <h3 id="writeConcern"><a href="#writeConcern">option: writeConcern</a></h3>
-
-    Allows setting [write concern](https://docs.mongodb.com/manual/reference/write-concern/)
-    at the schema level.
-
-    ```javascript
-    const schema = new Schema({ name: String }, {
-      writeConcern: {
-        w: 'majority',
-        j: true,
-        wtimeout: 1000
-      }
-    });
-    ```
-
-    <h3 id="shardKey"><a href="#shardKey">option: shardKey</a></h3>
-
-    The `shardKey` option is used when we have a [sharded MongoDB architecture](http://www.mongodb.org/display/DOCS/Sharding+Introduction).
-    Each sharded collection is given a shard key which must be present in all
-    insert/update operations. We just need to set this schema option to the same
-    shard key and we’ll be all set.
-
-    ```javascript
-    new Schema({ .. }, { shardKey: { tag: 1, name: 1 }})
-    ```
-
-    _Note that Mongoose does not send the `shardcollection` command for you. You
-    must configure your shards yourself._
-
-    <h3 id="strict"><a href="#strict">option: strict</a></h3>
-
-    The strict option, (enabled by default), ensures that values passed to our
-    model constructor that were not specified in our schema do not get saved to
-    the db.
-
-    ```javascript
-    const thingSchema = new Schema({..})
-    const Thing = mongoose.model('Thing', thingSchema);
-    const thing = new Thing({ iAmNotInTheSchema: true });
-    thing.save(); // iAmNotInTheSchema is not saved to the db
-
-    // set to false..
-    const thingSchema = new Schema({..}, { strict: false });
-    const thing = new Thing({ iAmNotInTheSchema: true });
-    thing.save(); // iAmNotInTheSchema is now saved to the db!!
-    ```
-
-    This also affects the use of `doc.set()` to set a property value.
-
-    ```javascript
-    const thingSchema = new Schema({..})
-    const Thing = mongoose.model('Thing', thingSchema);
-    const thing = new Thing;
-    thing.set('iAmNotInTheSchema', true);
-    thing.save(); // iAmNotInTheSchema is not saved to the db
-    ```
-
-    This value can be overridden at the model instance level by passing a second
-    boolean argument:
-
-    ```javascript
-    const Thing = mongoose.model('Thing');
-    const thing = new Thing(doc, true);  // enables strict mode
-    const thing = new Thing(doc, false); // disables strict mode
-    ```
-
-    The `strict` option may also be set to `"throw"` which will cause errors
-    to be produced instead of dropping the bad data.
-
-    _NOTE: Any key/val set on the instance that does not exist in your schema
-    is always ignored, regardless of schema option._
-
-    ```javascript
-    const thingSchema = new Schema({..})
-    const Thing = mongoose.model('Thing', thingSchema);
-    const thing = new Thing;
-    thing.iAmNotInTheSchema = true;
-    thing.save(); // iAmNotInTheSchema is never saved to the db
-    ```
-
-    <h3 id="strictQuery"><a href="#strictQuery">option: strictQuery</a></h3>
-
-    For backwards compatibility, the `strict` option does **not** apply to
-    the `filter` parameter for queries.
-
-    ```javascript
-    const mySchema = new Schema({ field: Number }, { strict: true });
-    const MyModel = mongoose.model('Test', mySchema);
-
-    // Mongoose will **not** filter out `notInSchema: 1`, despite `strict: true`
-    MyModel.find({ notInSchema: 1 });
-    ```
-
-    The `strict` option does apply to updates.
-
-    ```javascript
-    // Mongoose will strip out `notInSchema` from the update if `strict` is
-    // not `false`
-    MyModel.updateMany({}, { $set: { notInSchema: 1 } });
-    ```
-
-    Mongoose has a separate `strictQuery` option to toggle strict mode for
-    the `filter` parameter to queries.
-
-    ```javascript
-    const mySchema = new Schema({ field: Number }, {
-      strict: true,
-      strictQuery: true // Turn on strict mode for query filters
-    });
-    const MyModel = mongoose.model('Test', mySchema);
-
-    // Mongoose will strip out `notInSchema: 1` because `strictQuery` is `true`
-    MyModel.find({ notInSchema: 1 });
-    ```
-
-    <h3 id="toJSON"><a href="#toJSON">option: toJSON</a></h3>
-
-    Exactly the same as the [toObject](#toObject) option but only applies when
-    the document's [`toJSON` method](https://thecodebarbarian.com/what-is-the-tojson-function-in-javascript.html) is called.
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    schema.path('name').get(function (v) {
-      return v + ' is my name';
-    });
-    schema.set('toJSON', { getters: true, virtuals: false });
-    const M = mongoose.model('Person', schema);
-    const m = new M({ name: 'Max Headroom' });
-    console.log(m.toObject()); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom' }
-    console.log(m.toJSON()); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }
-    // since we know toJSON is called whenever a js object is stringified:
-    console.log(JSON.stringify(m)); // { "_id": "504e0cd7dd992d9be2f20b6f", "name": "Max Headroom is my name" }
-    ```
-
-    To see all available `toJSON/toObject` options, read [this](/docs/api.html#document_Document-toObject).
-
-    <h3 id="toObject"><a href="#toObject">option: toObject</a></h3>
-
-    Documents have a [toObject](/docs/api.html#document_Document-toObject) method
-    which converts the mongoose document into a plain JavaScript object. This
-    method accepts a few options. Instead of applying these options on a
-    per-document basis, we may declare the options at the schema level and have
-    them applied to all of the schema's documents by default.
-
-    To have all virtuals show up in your `console.log` output, set the
-    `toObject` option to `{ getters: true }`:
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    schema.path('name').get(function(v) {
-      return v + ' is my name';
-    });
-    schema.set('toObject', { getters: true });
-    const M = mongoose.model('Person', schema);
-    const m = new M({ name: 'Max Headroom' });
-    console.log(m); // { _id: 504e0cd7dd992d9be2f20b6f, name: 'Max Headroom is my name' }
-    ```
-
-    To see all available `toObject` options, read [this](/docs/api.html#document_Document-toObject).
-
-    <h3 id="typeKey"><a href="#typeKey">option: typeKey</a></h3>
-
-    By default, if you have an object with key 'type' in your schema, mongoose
-    will interpret it as a type declaration.
-
-    ```javascript
-    // Mongoose interprets this as 'loc is a String'
-    const schema = new Schema({ loc: { type: String, coordinates: [Number] } });
-    ```
-
-    However, for applications like [geoJSON](http://docs.mongodb.org/manual/reference/geojson/),
-    the 'type' property is important. If you want to control which key mongoose
-    uses to find type declarations, set the 'typeKey' schema option.
-
-    ```javascript
-    const schema = new Schema({
-      // Mongoose interpets this as 'loc is an object with 2 keys, type and coordinates'
-      loc: { type: String, coordinates: [Number] },
-      // Mongoose interprets this as 'name is a String'
-      name: { $type: String }
-    }, { typeKey: '$type' }); // A '$type' key means this object is a type declaration
-    ```
-
-    <h3 id="validateBeforeSave"><a href="#validateBeforeSave">option: validateBeforeSave</a></h3>
-
-    By default, documents are automatically validated before they are saved to
-    the database. This is to prevent saving an invalid document. If you want to
-    handle validation manually, and be able to save objects which don't pass
-    validation, you can set `validateBeforeSave` to false.
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    schema.set('validateBeforeSave', false);
-    schema.path('name').validate(function (value) {
-        return value != null;
-    });
-    const M = mongoose.model('Person', schema);
-    const m = new M({ name: null });
-    m.validate(function(err) {
-        console.log(err); // Will tell you that null is not allowed.
-    });
-    m.save(); // Succeeds despite being invalid
-    ```
-
-    <h3 id="versionKey"><a href="#versionKey">option: versionKey</a></h3>
-
-    The `versionKey` is a property set on each document when first created by
-    Mongoose. This keys value contains the internal
-    [revision](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)
-    of the document. The `versionKey` option is a string that represents the
-    path to use for versioning. The default is `__v`. If this conflicts with
-    your application you can configure as such:
-
-    ```javascript
-    const schema = new Schema({ name: 'string' });
-    const Thing = mongoose.model('Thing', schema);
-    const thing = new Thing({ name: 'mongoose v3' });
-    await thing.save(); // { __v: 0, name: 'mongoose v3' }
-
-    // customized versionKey
-    new Schema({..}, { versionKey: '_somethingElse' })
-    const Thing = mongoose.model('Thing', schema);
-    const thing = new Thing({ name: 'mongoose v3' });
-    thing.save(); // { _somethingElse: 0, name: 'mongoose v3' }
-    ```
-
-    Note that Mongoose's default versioning is **not** a full [optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control)
-    solution. Mongoose's default versioning only operates on arrays as shown below.
-
-    ```javascript
-    // 2 copies of the same document
-    const doc1 = await Model.findOne({ _id });
-    const doc2 = await Model.findOne({ _id });
-
-    // Delete first 3 comments from `doc1`
-    doc1.comments.splice(0, 3);
-    await doc1.save();
-
-    // The below `save()` will throw a VersionError, because you're trying to
-    // modify the comment at index 1, and the above `splice()` removed that
-    // comment.
-    doc2.set('comments.1.body', 'new comment');
-    await doc2.save();
-    ```
-
-    If you need optimistic concurrency support for `save()`, you can set the [`optimisticConcurrency` option](#optimisticConcurrency)
-
-    Document versioning can also be disabled by setting the `versionKey` to
-    `false`.
-    _DO NOT disable versioning unless you [know what you are doing](http://aaronheckmann.blogspot.com/2012/06/mongoose-v3-part-1-versioning.html)._
-
-    ```javascript
-    new Schema({..}, { versionKey: false });
-    const Thing = mongoose.model('Thing', schema);
-    const thing = new Thing({ name: 'no versioning please' });
-    thing.save(); // { name: 'no versioning please' }
-    ```
-
-    Mongoose _only_ updates the version key when you use [`save()`](/docs/api.html#document_Document-save).
-    If you use `update()`, `findOneAndUpdate()`, etc. Mongoose will **not**
-    update the version key. As a workaround, you can use the below middleware.
-
-    ```javascript
-    schema.pre('findOneAndUpdate', function() {
-      const update = this.getUpdate();
-      if (update.__v != null) {
-        delete update.__v;
-      }
-      const keys = ['$set', '$setOnInsert'];
-      for (const key of keys) {
-        if (update[key] != null && update[key].__v != null) {
-          delete update[key].__v;
-          if (Object.keys(update[key]).length === 0) {
-            delete update[key];
-          }
-        }
-      }
-      update.$inc = update.$inc || {};
-      update.$inc.__v = 1;
-    });
-    ```
-
-    <h3 id="optimisticConcurrency"><a href="#optimisticConcurrency">option: optimisticConcurrency</a></h3>
-
-    [Optimistic concurrency](https://en.wikipedia.org/wiki/Optimistic_concurrency_control) is a strategy to ensure
-    the document you're updating didn't change between when you loaded it using `find()` or `findOne()`, and when
-    you update it using `save()`.
-
-    For example, suppose you have a `House` model that contains a list of `photos`, and a `status` that represents
-    whether this house shows up in searches. Suppose that a house that has status `'APPROVED'` must have at least
-    two `photos`. You might implement the logic of approving a house document as shown below:
-
-    ```javascript
-    async function markApproved(id) {
-      const house = await House.findOne({ _id });
-      if (house.photos.length < 2) {
-        throw new Error('House must have at least two photos!');
-      }
-      
-      house.status = 'APPROVED';
-      await house.save();
-    }
-    ```
-
-    The `markApproved()` function looks right in isolation, but there might be a potential issue: what if another
-    function removes the house's photos between the `findOne()` call and the `save()` call? For example, the below
-    code will succeed:
-
-    ```javascript
-    const house = await House.findOne({ _id });
-    if (house.photos.length < 2) {
-      throw new Error('House must have at least two photos!');
-    }
-
-    const house2 = await House.findOne({ _id });
-    house2.photos = [];
-    await house2.save();
-
-    // Marks the house as 'APPROVED' even though it has 0 photos!
-    house.status = 'APPROVED';
-    await house.save();
-    ```
-
-    If you set the `optimisticConcurrency` option on the `House` model's schema, the above script will throw an
-    error.
-
-    ```javascript
-    const House = mongoose.model('House', Schema({
-      status: String,
-      photos: [String]
-    }, { optimisticConcurrency: true }));
-
-    const house = await House.findOne({ _id });
-    if (house.photos.length < 2) {
-      throw new Error('House must have at least two photos!');
-    }
-
-    const house2 = await House.findOne({ _id });
-    house2.photos = [];
-    await house2.save();
-
-    // Throws 'VersionError: No matching document found for id "..." version 0'
-    house.status = 'APPROVED';
-    await house.save();
-    ```
-
-    <h3 id="collation"><a href="#collation">option: collation</a></h3>
-
-    Sets a default [collation](https://docs.mongodb.com/manual/reference/collation/)
-    for every query and aggregation. [Here's a beginner-friendly overview of collations](http://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-collations).
-
-    ```javascript
-    const schema = new Schema({
-      name: String
-    }, { collation: { locale: 'en_US', strength: 1 } });
-
-    const MyModel = db.model('MyModel', schema);
-
-    MyModel.create([{ name: 'val' }, { name: 'Val' }]).
-      then(() => {
-        return MyModel.find({ name: 'val' });
-      }).
-      then((docs) => {
-        // `docs` will contain both docs, because `strength: 1` means
-        // MongoDB will ignore case when matching.
-      });
-    ```
-
-    <h3 id="skipVersioning"><a href="#skipVersioning">option: skipVersioning</a></h3>
-
-    `skipVersioning` allows excluding paths from versioning (i.e., the internal
-    revision will not be incremented even if these paths are updated). DO NOT
-    do this unless you know what you're doing. For subdocuments, include this
-    on the parent document using the fully qualified path.
-
-    ```javascript
-    new Schema({..}, { skipVersioning: { dontVersionMe: true } });
-    thing.dontVersionMe.push('hey');
-    thing.save(); // version is not incremented
-    ```
-
-    <h3 id="timestamps"><a href="#timestamps">option: timestamps</a></h3>
-
-    The `timestamps` option tells mongoose to assign `createdAt` and `updatedAt` fields
-    to your schema. The type assigned is [Date](./api.html#schema-date-js).
-
-    By default, the names of the fields are `createdAt` and `updatedAt`. Customize
-    the field names by setting `timestamps.createdAt` and `timestamps.updatedAt`.
-
-    ```javascript
-    const thingSchema = new Schema({..}, { timestamps: { createdAt: 'created_at' } });
-    const Thing = mongoose.model('Thing', thingSchema);
-    const thing = new Thing();
-    await thing.save(); // `created_at` & `updatedAt` will be included
-
-    // With updates, Mongoose will add `updatedAt` to `$set`
-    await Thing.updateOne({}, { $set: { name: 'Test' } });
-
-    // If you set upsert: true, Mongoose will add `created_at` to `$setOnInsert` as well
-    await Thing.findOneAndUpdate({}, { $set: { name: 'Test2' } });
-
-    // Mongoose also adds timestamps to bulkWrite() operations
-    // See https://mongoosejs.com/docs/api.html#model_Model.bulkWrite
-    await Thing.bulkWrite([
-      insertOne: {
-        document: {
-          name: 'Jean-Luc Picard',
-          ship: 'USS Stargazer'
-          // Mongoose will add `created_at` and `updatedAt`
-        }
-      },
-      updateOne: {
-        filter: { name: 'Jean-Luc Picard' },
-        update: {
-          $set: {
-            ship: 'USS Enterprise'
-            // Mongoose will add `updatedAt`
-          }
-        }
-      }
-    ]);
-    ```
-
-    By default, Mongoose uses `new Date()` to get the current time.
-    If you want to overwrite the function
-    Mongoose uses to get the current time, you can set the
-    `timestamps.currentTime` option. Mongoose will call the
-    `timestamps.currentTime` function whenever it needs to get
-    the current time.
-
-    ```javascript
-    const schema = Schema({
-      createdAt: Number,
-      updatedAt: Number,
-      name: String
-    }, {
-      // Make Mongoose use Unix time (seconds since Jan 1, 1970)
-      timestamps: { currentTime: () => Math.floor(Date.now() / 1000) }
-    });
-    ```
-
-    <h3 id="useNestedStrict"><a href="#useNestedStrict">option: useNestedStrict</a></h3>
-
-    Write operations like `update()`, `updateOne()`, `updateMany()`,
-    and `findOneAndUpdate()` only check the top-level
-    schema's strict mode setting.
-
-    ```javascript
-    const childSchema = new Schema({}, { strict: false });
-    const parentSchema = new Schema({ child: childSchema }, { strict: 'throw' });
-    const Parent = mongoose.model('Parent', parentSchema);
-    Parent.update({}, { 'child.name': 'Luke Skywalker' }, (error) => {
-      // Error because parentSchema has `strict: throw`, even though
-      // `childSchema` has `strict: false`
-    });
-
-    const update = { 'child.name': 'Luke Skywalker' };
-    const opts = { strict: false };
-    Parent.update({}, update, opts, function(error) {
-      // This works because passing `strict: false` to `update()` overwrites
-      // the parent schema.
-    });
-    ```
-
-    If you set `useNestedStrict` to true, mongoose will use the child schema's
-    `strict` option for casting updates.
-
-    ```javascript
-    const childSchema = new Schema({}, { strict: false });
-    const parentSchema = new Schema({ child: childSchema },
-      { strict: 'throw', useNestedStrict: true });
-    const Parent = mongoose.model('Parent', parentSchema);
-    Parent.update({}, { 'child.name': 'Luke Skywalker' }, error => {
-      // Works!
-    });
-    ```
-
-    <h3 id="selectPopulatedPaths">
-      <a href="#selectPopulatedPaths">
-        option: selectPopulatedPaths
-      </a>
-    </h3>
-
-    By default, Mongoose will automatically `select()` any populated paths for
-    you, unless you explicitly exclude them.
-
-    ```javascript
-    const bookSchema = new Schema({
-      title: 'String',
-      author: { type: 'ObjectId', ref: 'Person' }
-    });
-    const Book = mongoose.model('Book', bookSchema);
-
-    // By default, Mongoose will add `author` to the below `select()`.
-    await Book.find().select('title').populate('author');
-
-    // In other words, the below query is equivalent to the above
-    await Book.find().select('title author').populate('author');
-    ```
-
-    To opt out of selecting populated fields by default, set `selectPopulatedPaths`
-    to `false` in your schema.
-
-    ```javascript
-    const bookSchema = new Schema({
-      title: 'String',
-      author: { type: 'ObjectId', ref: 'Person' }
-    }, { selectPopulatedPaths: false });
-    const Book = mongoose.model('Book', bookSchema);
-
-    // Because `selectPopulatedPaths` is false, the below doc will **not**
-    // contain an `author` property.
-    const doc = await Book.findOne().select('title').populate('author');
-    ```
-
-    <h3 id="storeSubdocValidationError">
-      <a href="#storeSubdocValidationError">
-        option: storeSubdocValidationError
-      </a>
-    </h3>
-
-    For legacy reasons, when there is a validation error in subpath of a
-    single nested schema, Mongoose will record that there was a validation error
-    in the single nested schema path as well. For example:
-
-    ```javascript
-    const childSchema = new Schema({ name: { type: String, required: true } });
-    const parentSchema = new Schema({ child: childSchema });
-
-    const Parent = mongoose.model('Parent', parentSchema);
-
-    // Will contain an error for both 'child.name' _and_ 'child'
-    new Parent({ child: {} }).validateSync().errors;
-    ```
-
-    Set the `storeSubdocValidationError` to `false` on the child schema to make
-    Mongoose only reports the parent error.
-
-    ```javascript
-    const childSchema = new Schema({
-      name: { type: String, required: true }
-    }, { storeSubdocValidationError: false }); // <-- set on the child schema
-    const parentSchema = new Schema({ child: childSchema });
-
-    const Parent = mongoose.model('Parent', parentSchema);
-
-    // Will only contain an error for 'child.name'
-    new Parent({ child: {} }).validateSync().errors;
-    ```
-
-    <h3 id="es6-classes"><a href="#es6-classes">With ES6 Classes</a></h3>
-
-    Schemas have a [`loadClass()` method](/docs/api/schema.html#schema_Schema-loadClass)
-    that you can use to create a Mongoose schema from an [ES6 class](https://thecodebarbarian.com/an-overview-of-es6-classes):
-
-    * [ES6 class methods](https://masteringjs.io/tutorials/fundamentals/class#methods) become [Mongoose methods](/docs/guide.html#methods)
-    * [ES6 class statics](https://masteringjs.io/tutorials/fundamentals/class#statics) become [Mongoose statics](/docs/guide.html#statics)
-    * [ES6 getters and setters](https://masteringjs.io/tutorials/fundamentals/class#getterssetters) become [Mongoose virtuals](/docs/tutorials/virtuals.html)
-
-    Here's an example of using `loadClass()` to create a schema from an ES6 class:
-
-    ```javascript
-    class MyClass {
-      myMethod() { return 42; }
-      static myStatic() { return 42; }
-      get myVirtual() { return 42; }
-    }
-
-    const schema = new mongoose.Schema();
-    schema.loadClass(MyClass);
-
-    console.log(schema.methods); // { myMethod: [Function: myMethod] }
-    console.log(schema.statics); // { myStatic: [Function: myStatic] }
-    console.log(schema.virtuals); // { myVirtual: VirtualType { ... } }
-    ```
-
-    <h3 id="plugins"><a href="#plugins">Pluggable</a></h3>
-
-    Schemas are also [pluggable](./plugins.html) which allows us to package up reusable features into
-    plugins that can be shared with the community or just between your projects.
-
-    <h3 id="further-reading">Further Reading</h3>
-
-    Here's an [alternative introduction to Mongoose schemas](https://masteringjs.io/tutorials/mongoose/schema).
-
-    To get the most out of MongoDB, you need to learn the basics of MongoDB schema design.
-    SQL schema design (third normal form) was designed to [minimize storage costs](https://en.wikipedia.org/wiki/Third_normal_form),
-    whereas MongoDB schema design is about making common queries as fast as possible.
-    The [_6 Rules of Thumb for MongoDB Schema Design_ blog series](https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-1)
-    is an excellent resource for learning the basic rules for making your queries
-    fast.
-
-    Users looking to master MongoDB schema design in Node.js should look into
-    [_The Little MongoDB Schema Design Book_](http://bit.ly/mongodb-schema-design)
-    by Christian Kvalheim, the original author of the [MongoDB Node.js driver](http://npmjs.com/package/mongodb).
-    This book shows you how to implement performant schemas for a laundry list
-    of use cases, including e-commerce, wikis, and appointment bookings.
-
-    <h3 id="next">Next Up</h3>
-
-    Now that we've covered `Schemas`, let's take a look at [SchemaTypes](/docs/schematypes.html).
diff --git a/docs/guides.md b/docs/guides.md
new file mode 100644
index 00000000000..c8196bfa341
--- /dev/null
+++ b/docs/guides.md
@@ -0,0 +1,47 @@
+## Guides
+
+Mongoose guides provide detailed tutorials on Mongoose's core concepts and
+integrating Mongoose with external tools and frameworks.
+
+### Mongoose Core Concepts
+
+* [Schemas](/docs/guide.html)
+* [SchemaTypes](/docs/schematypes.html)
+* [Connections](/docs/connections.html)
+* [Models](/docs/models.html)
+* [Documents](/docs/documents.html)
+* [Subdocuments](/docs/subdocs.html)
+* [Queries](/docs/queries.html)
+* [Validation](/docs/validation.html)
+* [Middleware](/docs/middleware.html)
+* [Populate](/docs/populate.html)
+* [Discriminators](/docs/discriminators.html)
+* [Plugins](/docs/plugins.html)
+* [Faster Mongoose Queries With Lean](/docs/tutorials/lean.html)
+* [Query Casting](/docs/tutorials/query_casting.html)
+* [findOneAndUpdate](/docs/tutorials/findoneandupdate.html)
+* [Getters and Setters](/docs/tutorials/getters-setters.html)
+* [Virtuals](/docs/tutorials/virtuals.html)
+
+### Advanced Topics
+
+* [Working with Dates](/docs/tutorials/dates.html)
+* [Custom Casting For Built-in Types](/docs/tutorials/custom-casting.html)
+* [Custom SchemaTypes](/docs/customschematypes.html)
+
+### Integrations
+
+* [Promises](/docs/promises.html)
+* [AWS Lambda](/docs/lambda.html)
+* [Browser Library](/docs/browser.html)
+* [GeoJSON](/docs/geojson.html)
+* [Transactions](/docs/transactions.html)
+* [MongoDB Driver Deprecation Warnings](/docs/deprecations.html)
+* [Testing with Jest](/docs/jest.html)
+* [SSL Connections](/docs/tutorials/ssl.html)
+
+### Migration Guides
+
+* [Mongoose 4.x to 5.x](/docs/migrating_to_5.html)
+* [Mongoose 3.x to 4.x](/docs/migration.html)
+
diff --git a/docs/guides.pug b/docs/guides.pug
deleted file mode 100644
index 04f6312edb3..00000000000
--- a/docs/guides.pug
+++ /dev/null
@@ -1,69 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    ## Guides
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    Mongoose guides provide detailed tutorials on Mongoose's core concepts and
-    integrating Mongoose with external tools and frameworks.
-
-    ### Mongoose Core Concepts
-
-    * [Schemas](/docs/guide.html)
-    * [SchemaTypes](/docs/schematypes.html)
-    * [Connections](/docs/connections.html)
-    * [Models](/docs/models.html)
-    * [Documents](/docs/documents.html)
-    * [Subdocuments](/docs/subdocs.html)
-    * [Queries](/docs/queries.html)
-    * [Validation](/docs/validation.html)
-    * [Middleware](/docs/middleware.html)
-    * [Populate](/docs/populate.html)
-    * [Discriminators](/docs/discriminators.html)
-    * [Plugins](/docs/plugins.html)
-    * [Faster Mongoose Queries With Lean](/docs/tutorials/lean.html)
-    * [Query Casting](/docs/tutorials/query_casting.html)
-    * [findOneAndUpdate](/docs/tutorials/findoneandupdate.html)
-    * [Getters and Setters](/docs/tutorials/getters-setters.html)
-    * [Virtuals](/docs/tutorials/virtuals.html)
-
-    ### Advanced Topics
-
-    * [Working with Dates](/docs/tutorials/dates.html)
-    * [Custom Casting For Built-in Types](/docs/tutorials/custom-casting.html)
-    * [Custom SchemaTypes](/docs/customschematypes.html)
-
-    ### Integrations
-
-    * [Promises](/docs/promises.html)
-    * [AWS Lambda](/docs/lambda.html)
-    * [Browser Library](/docs/browser.html)
-    * [GeoJSON](/docs/geojson.html)
-    * [Transactions](/docs/transactions.html)
-    * [MongoDB Driver Deprecation Warnings](/docs/deprecations.html)
-    * [Testing with Jest](/docs/jest.html)
-    * [SSL Connections](/docs/tutorials/ssl.html)
-
-    ### Migration Guides
-
-    * [Mongoose 4.x to 5.x](/docs/migrating_to_5.html)
-    * [Mongoose 3.x to 4.x](/docs/migration.html)
-
diff --git a/docs/index.md b/docs/index.md
new file mode 100644
index 00000000000..2668ace614e
--- /dev/null
+++ b/docs/index.md
@@ -0,0 +1,128 @@
+## Getting Started
+
+<style>
+  hr {
+    display: block;
+    margin-top: 40px;
+    margin-bottom: 40px;
+    border: 0px;
+    height: 1px;
+    background-color: #232323;
+    width: 100%;
+  }
+</style>
+
+_First be sure you have [MongoDB](http://www.mongodb.org/downloads) and [Node.js](http://nodejs.org/) installed._
+
+Next install Mongoose from the command line using `npm`:
+
+```
+$ npm install mongoose --save
+```
+
+Now say we like fuzzy kittens and want to record every kitten we ever meet
+in MongoDB.
+The first thing we need to do is include mongoose in our project and open a
+connection to the `test` database on our locally running instance of MongoDB.
+
+```javascript
+// getting-started.js
+const mongoose = require('mongoose');
+mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true, useUnifiedTopology: true});
+```
+
+We have a pending connection to the test database running on localhost.
+We now need to get notified if we connect successfully or if a connection
+error occurs:
+
+```javascript
+const db = mongoose.connection;
+db.on('error', console.error.bind(console, 'connection error:'));
+db.once('open', function() {
+  // we're connected!
+});
+```
+
+Once our connection opens, our callback will be called. For brevity,
+let's assume that all following code is within this callback.
+
+With Mongoose, everything is derived from a [Schema](/docs/guide.html).
+Let's get a reference to it and define our kittens.
+
+```javascript
+const kittySchema = new mongoose.Schema({
+  name: String
+});
+```
+
+So far so good. We've got a schema with one property, `name`, which will be a  `String`. The next step is compiling our schema into a [Model](/docs/models.html).
+
+```javascript
+const Kitten = mongoose.model('Kitten', kittySchema);
+```
+
+A model is a class with which we construct documents.
+In this case, each document will be a kitten with properties and behaviors as declared in our schema.
+Let's create a kitten document representing the little guy we just met on the sidewalk outside:
+
+```javascript
+const silence = new Kitten({ name: 'Silence' });
+console.log(silence.name); // 'Silence'
+```
+
+Kittens can meow, so let's take a look at how to add "speak" functionality
+to our documents:
+
+```javascript
+// NOTE: methods must be added to the schema before compiling it with mongoose.model()
+kittySchema.methods.speak = function () {
+  const greeting = this.name
+    ? "Meow name is " + this.name
+    : "I don't have a name";
+  console.log(greeting);
+}
+
+const Kitten = mongoose.model('Kitten', kittySchema);
+```
+
+Functions added to the `methods` property of a schema get compiled into
+the `Model` prototype and exposed on each document instance:
+
+```javascript
+const fluffy = new Kitten({ name: 'fluffy' });
+fluffy.speak(); // "Meow name is fluffy"
+```
+
+We have talking kittens! But we still haven't saved anything to MongoDB.
+Each document can be saved to the database by calling its [save](/docs/api.html#model_Model-save) method. The first argument to the callback will be an error if any occurred.
+
+```javascript
+  fluffy.save(function (err, fluffy) {
+    if (err) return console.error(err);
+    fluffy.speak();
+  });
+```
+
+Say time goes by and we want to display all the kittens we've seen.
+We can access all of the kitten documents through our Kitten [model](/docs/models.html).
+
+```javascript
+Kitten.find(function (err, kittens) {
+  if (err) return console.error(err);
+  console.log(kittens);
+})
+```
+
+We just logged all of the kittens in our db to the console.
+If we want to filter our kittens by name, Mongoose supports MongoDBs rich [querying](/docs/queries.html) syntax.
+
+```javascript
+Kitten.find({ name: /^fluff/ }, callback);
+```
+
+This performs a search for all documents with a name property that begins
+with "fluff" and returns the result as an array of kittens to the callback.
+
+### Congratulations
+
+That's the end of our quick start. We created a schema, added a custom document method, saved and queried kittens in MongoDB using Mongoose. Head over to the [guide](guide.html), or [API docs](api.html) for more.
diff --git a/docs/index.pug b/docs/index.pug
deleted file mode 100644
index a1c0ecb06f2..00000000000
--- a/docs/index.pug
+++ /dev/null
@@ -1,132 +0,0 @@
-extends layout
-
-block append style
-  style.
-    hr {
-      display: block;
-      margin-top: 40px;
-      margin-bottom: 40px;
-      border: 0px;
-      height: 1px;
-      background-color: #232323;
-      width: 100%;
-    }
-
-block content
-  :markdown
-    ## Getting Started
-
-    _First be sure you have [MongoDB](http://www.mongodb.org/downloads) and [Node.js](http://nodejs.org/) installed._
-
-    Next install Mongoose from the command line using `npm`:
-
-    ```
-    $ npm install mongoose --save
-    ```
-
-    Now say we like fuzzy kittens and want to record every kitten we ever meet
-    in MongoDB.
-    The first thing we need to do is include mongoose in our project and open a
-    connection to the `test` database on our locally running instance of MongoDB.
-
-    ```javascript
-    // getting-started.js
-    const mongoose = require('mongoose');
-    mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true, useUnifiedTopology: true});
-    ```
-
-    We have a pending connection to the test database running on localhost.
-    We now need to get notified if we connect successfully or if a connection
-    error occurs:
-
-    ```javascript
-    const db = mongoose.connection;
-    db.on('error', console.error.bind(console, 'connection error:'));
-    db.once('open', function() {
-      // we're connected!
-    });
-    ```
-
-    Once our connection opens, our callback will be called. For brevity,
-    let's assume that all following code is within this callback.
-
-    With Mongoose, everything is derived from a [Schema](/docs/guide.html).
-    Let's get a reference to it and define our kittens.
-
-    ```javascript
-    const kittySchema = new mongoose.Schema({
-      name: String
-    });
-    ```
-
-    So far so good. We've got a schema with one property, `name`, which will be a  `String`. The next step is compiling our schema into a [Model](/docs/models.html).
-
-    ```javascript
-    const Kitten = mongoose.model('Kitten', kittySchema);
-    ```
-
-    A model is a class with which we construct documents.
-    In this case, each document will be a kitten with properties and behaviors as declared in our schema.
-    Let's create a kitten document representing the little guy we just met on the sidewalk outside:
-
-    ```javascript
-    const silence = new Kitten({ name: 'Silence' });
-    console.log(silence.name); // 'Silence'
-    ```
-
-    Kittens can meow, so let's take a look at how to add "speak" functionality
-    to our documents:
-
-    ```javascript
-    // NOTE: methods must be added to the schema before compiling it with mongoose.model()
-    kittySchema.methods.speak = function () {
-      const greeting = this.name
-        ? "Meow name is " + this.name
-        : "I don't have a name";
-      console.log(greeting);
-    }
-
-    const Kitten = mongoose.model('Kitten', kittySchema);
-    ```
-
-    Functions added to the `methods` property of a schema get compiled into
-    the `Model` prototype and exposed on each document instance:
-
-    ```javascript
-    const fluffy = new Kitten({ name: 'fluffy' });
-    fluffy.speak(); // "Meow name is fluffy"
-    ```
-
-    We have talking kittens! But we still haven't saved anything to MongoDB.
-    Each document can be saved to the database by calling its [save](/docs/api.html#model_Model-save) method. The first argument to the callback will be an error if any occurred.
-
-    ```javascript
-      fluffy.save(function (err, fluffy) {
-        if (err) return console.error(err);
-        fluffy.speak();
-      });
-    ```
-
-    Say time goes by and we want to display all the kittens we've seen.
-    We can access all of the kitten documents through our Kitten [model](/docs/models.html).
-
-    ```javascript
-    Kitten.find(function (err, kittens) {
-      if (err) return console.error(err);
-      console.log(kittens);
-    })
-    ```
-
-    We just logged all of the kittens in our db to the console.
-    If we want to filter our kittens by name, Mongoose supports MongoDBs rich [querying](/docs/queries.html) syntax.
-
-    ```javascript
-    Kitten.find({ name: /^fluff/ }, callback);
-    ```
-
-    This performs a search for all documents with a name property that begins
-    with "fluff" and returns the result as an array of kittens to the callback.
-
-    ### Congratulations
-
-    That's the end of our quick start. We created a schema, added a custom document method, saved and queried kittens in MongoDB using Mongoose. Head over to the [guide](guide.html), or [API docs](api.html) for more.
diff --git a/docs/production.pug b/docs/production.pug
deleted file mode 100644
index 2dd82917635..00000000000
--- a/docs/production.pug
+++ /dev/null
@@ -1,13 +0,0 @@
-extends redirect
-
-block meta
-  meta(http-equiv="refresh", content="5;url=http://mongoosejs.tumblr.com/")
-
-block content
-  p
-    | You are being redirected to http://mongoosejs.tumblr.com.
-    br
-    | Please 
-    a(href="http://mongoosejs.tumblr.com/") click here
-    |  if you are not redirected in 5 seconds.
-
diff --git a/docs/schematypes.md b/docs/schematypes.md
new file mode 100644
index 00000000000..bcc2cc5a9ce
--- /dev/null
+++ b/docs/schematypes.md
@@ -0,0 +1,739 @@
+<h2 id="schematypes"><a href="#schematypes">SchemaTypes</a></h2>
+
+SchemaTypes handle definition of path
+[defaults](./api.html#schematype_SchemaType-default),
+[validation](./api.html#schematype_SchemaType-validate),
+[getters](#getters),
+[setters](./api.html#schematype_SchemaType-set),
+[field selection defaults](./api.html#schematype_SchemaType-select) for
+[queries](./api.html#query-js),
+and other general characteristics for Mongoose document properties.
+
+<ul class="toc">
+  <li><a href="#what-is-a-schema-type">What is a SchemaType?</a></li>
+  <li><a href="#schematype-options">SchemaType Options</a></li>
+  <li><a href="#customtypes">Creating Custom Types</a></li>
+  <li><a href="#path">The `schema.path()` Function</a></li>
+  <li><a href="#further-reading">Further Reading</a></li>
+</ul>
+
+* [What is a SchemaType?](#what-is-a-schematype)
+* [The `type` Key](#type-key)
+* [SchemaType Options](#schematype-options)
+* [Usage Notes](#usage-notes)
+* [Getters](#getters)
+* [Custom Types](#customtypes)
+* [The `schema.path()` Function](#path)
+
+<h3 id="what-is-a-schematype"><a href="#what-is-a-schematype">What is a SchemaType?</a></h3>
+
+You can think of a Mongoose schema as the configuration object for a
+Mongoose model. A SchemaType is then a configuration object for an individual
+property. A SchemaType says what type a given
+path should have, whether it has any getters/setters, and what values are
+valid for that path.
+
+```javascript
+const schema = new Schema({ name: String });
+schema.path('name') instanceof mongoose.SchemaType; // true
+schema.path('name') instanceof mongoose.Schema.Types.String; // true
+schema.path('name').instance; // 'String'
+```
+
+A SchemaType is different from a type. In other words, `mongoose.ObjectId !== mongoose.Types.ObjectId`.
+A SchemaType is just a configuration object for Mongoose. An instance of
+the `mongoose.ObjectId` SchemaType doesn't actually create MongoDB ObjectIds,
+it is just a configuration for a path in a schema.
+
+The following are all the valid SchemaTypes in Mongoose. Mongoose plugins
+can also add custom SchemaTypes like [int32](http://plugins.mongoosejs.io/plugins/int32).
+Check out [Mongoose's plugins search](http://plugins.mongoosejs.io) to find plugins.
+
+- [String](#strings)
+- [Number](#numbers)
+- [Date](#dates)
+- [Buffer](#buffers)
+- [Boolean](#booleans)
+- [Mixed](#mixed)
+- [ObjectId](#objectids)
+- [Array](#arrays)
+- [Decimal128](./api.html#mongoose_Mongoose-Decimal128)
+- [Map](#maps)
+- [Schema](#schemas)
+
+<h4>Example</h4>
+
+```javascript
+const schema = new Schema({
+  name:    String,
+  binary:  Buffer,
+  living:  Boolean,
+  updated: { type: Date, default: Date.now },
+  age:     { type: Number, min: 18, max: 65 },
+  mixed:   Schema.Types.Mixed,
+  _someId: Schema.Types.ObjectId,
+  decimal: Schema.Types.Decimal128,
+  array: [],
+  ofString: [String],
+  ofNumber: [Number],
+  ofDates: [Date],
+  ofBuffer: [Buffer],
+  ofBoolean: [Boolean],
+  ofMixed: [Schema.Types.Mixed],
+  ofObjectId: [Schema.Types.ObjectId],
+  ofArrays: [[]],
+  ofArrayOfNumbers: [[Number]],
+  nested: {
+    stuff: { type: String, lowercase: true, trim: true }
+  },
+  map: Map,
+  mapOfString: {
+    type: Map,
+    of: String
+  }
+})
+
+// example use
+
+const Thing = mongoose.model('Thing', schema);
+
+const m = new Thing;
+m.name = 'Statue of Liberty';
+m.age = 125;
+m.updated = new Date;
+m.binary = Buffer.alloc(0);
+m.living = false;
+m.mixed = { any: { thing: 'i want' } };
+m.markModified('mixed');
+m._someId = new mongoose.Types.ObjectId;
+m.array.push(1);
+m.ofString.push("strings!");
+m.ofNumber.unshift(1,2,3,4);
+m.ofDates.addToSet(new Date);
+m.ofBuffer.pop();
+m.ofMixed = [1, [], 'three', { four: 5 }];
+m.nested.stuff = 'good';
+m.map = new Map([['key', 'value']]);
+m.save(callback);
+```
+
+<h3 id="type-key"><a href="#type-key">The `type` Key</a></h3>
+
+`type` is a special property in Mongoose schemas. When Mongoose finds
+a nested property named `type` in your schema, Mongoose assumes that
+it needs to define a SchemaType with the given type.
+
+```javascript
+// 3 string SchemaTypes: 'name', 'nested.firstName', 'nested.lastName'
+const schema = new Schema({
+  name: { type: String },
+  nested: {
+    firstName: { type: String },
+    lastName: { type: String }
+  }
+});
+```
+
+As a consequence, [you need a little extra work to define a property named `type` in your schema](/docs/faq.html#type-key).
+For example, suppose you're building a stock portfolio app, and you
+want to store the asset's `type` (stock, bond, ETF, etc.). Naively,
+you might define your schema as shown below:
+
+```javascript
+const holdingSchema = new Schema({
+  // You might expect `asset` to be an object that has 2 properties,
+  // but unfortunately `type` is special in Mongoose so mongoose
+  // interprets this schema to mean that `asset` is a string
+  asset: {
+    type: String,
+    ticker: String
+  }
+});
+```
+
+However, when Mongoose sees `type: String`, it assumes that you mean
+`asset` should be a string, not an object with a property `type`.
+The correct way to define an object with a property `type` is shown
+below.
+
+```javascript
+const holdingSchema = new Schema({
+  asset: {
+    // Workaround to make sure Mongoose knows `asset` is an object
+    // and `asset.type` is a string, rather than thinking `asset`
+    // is a string.
+    type: { type: String },
+    ticker: String
+  }
+});
+```
+
+<h3 id="schematype-options"><a href="#schematype-options">SchemaType Options</a></h3>
+
+You can declare a schema type using the type directly, or an object with
+a `type` property.
+
+```javascript
+const schema1 = new Schema({
+  test: String // `test` is a path of type String
+});
+
+const schema2 = new Schema({
+  // The `test` object contains the "SchemaType options"
+  test: { type: String } // `test` is a path of type string
+});
+```
+
+In addition to the type property, you can specify additional properties
+for a path. For example, if you want to lowercase a string before saving:
+
+```javascript
+const schema2 = new Schema({
+  test: {
+    type: String,
+    lowercase: true // Always convert `test` to lowercase
+  }
+});
+```
+
+You can add any property you want to your SchemaType options. Many plugins
+rely on custom SchemaType options. For example, the [mongoose-autopopulate](http://plugins.mongoosejs.io/plugins/autopopulate)
+plugin automatically populates paths if you set `autopopulate: true` in your
+SchemaType options. Mongoose comes with support for several built-in
+SchemaType options, like `lowercase` in the above example.
+
+The `lowercase` option only works for strings. There are certain options
+which apply for all schema types, and some that apply for specific schema
+types.
+
+<h5>All Schema Types</h5>
+
+* `required`: boolean or function, if true adds a [required validator](./validation.html#built-in-validators) for this property
+* `default`: Any or function, sets a default value for the path. If the value is a function, the return value of the function is used as the default.
+* `select`: boolean, specifies default [projections](https://docs.mongodb.com/manual/tutorial/project-fields-from-query-results/) for queries
+* `validate`: function, adds a [validator function](./validation.html#built-in-validators) for this property
+* `get`: function, defines a custom getter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
+* `set`: function, defines a custom setter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
+* `alias`: string, mongoose >= 4.10.0 only. Defines a [virtual](./guide.html#virtuals) with the given name that gets/sets this path.
+* `immutable`: boolean, defines path as immutable. Mongoose prevents you from changing immutable paths unless the parent document has `isNew: true`.
+* `transform`: function, Mongoose calls this function when you call [`Document#toJSON()`](/docs/api/document.html#document_Document-toJSON) function, including when you [`JSON.stringify()`](https://thecodebarbarian.com/the-80-20-guide-to-json-stringify-in-javascript) a document.
+
+```javascript
+const numberSchema = new Schema({
+  integerOnly: {
+    type: Number,
+    get: v => Math.round(v),
+    set: v => Math.round(v),
+    alias: 'i'
+  }
+});
+
+const Number = mongoose.model('Number', numberSchema);
+
+const doc = new Number();
+doc.integerOnly = 2.001;
+doc.integerOnly; // 2
+doc.i; // 2
+doc.i = 3.001;
+doc.integerOnly; // 3
+doc.i; // 3
+```
+
+<h5>Indexes</h5>
+
+You can also define [MongoDB indexes](https://docs.mongodb.com/manual/indexes/)
+using schema type options.
+
+* `index`: boolean, whether to define an [index](https://docs.mongodb.com/manual/indexes/) on this property.
+* `unique`: boolean, whether to define a [unique index](https://docs.mongodb.com/manual/core/index-unique/) on this property.
+* `sparse`: boolean, whether to define a [sparse index](https://docs.mongodb.com/manual/core/index-sparse/) on this property.
+
+```javascript
+const schema2 = new Schema({
+  test: {
+    type: String,
+    index: true,
+    unique: true // Unique index. If you specify `unique: true`
+    // specifying `index: true` is optional if you do `unique: true`
+  }
+});
+```
+
+<h5 id="string-validators">String</h5>
+
+* `lowercase`: boolean, whether to always call `.toLowerCase()` on the value
+* `uppercase`: boolean, whether to always call `.toUpperCase()` on the value
+* `trim`: boolean, whether to always call `.trim()` on the value
+* `match`: RegExp, creates a [validator](./validation.html) that checks if the value matches the given regular expression
+* `enum`: Array, creates a [validator](./validation.html) that checks if the value is in the given array.
+* `minLength`: Number, creates a [validator](./validation.html) that checks if the value length is not less than the given number
+* `maxLength`: Number, creates a [validator](./validation.html) that checks if the value length is not greater than the given number
+* `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
+
+<h5 id="number-validators">Number</h5>
+
+* `min`: Number, creates a [validator](./validation.html) that checks if the value is greater than or equal to the given minimum.
+* `max`: Number, creates a [validator](./validation.html) that checks if the value is less than or equal to the given maximum.
+* `enum`: Array, creates a [validator](./validation.html) that checks if the value is strictly equal to one of the values in the given array.
+* `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
+
+<h5>Date</h5>
+
+* `min`: Date
+* `max`: Date
+
+<h5>ObjectId</h5>
+
+* `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
+
+<h3 id="usage-notes"><a href="#usage-notes">Usage Notes</a></h3>
+
+<h4 id="strings">String</h4>
+
+To declare a path as a string, you may use either the `String` global
+constructor or the string `'String'`.
+
+```javascript
+const schema1 = new Schema({ name: String }); // name will be cast to string
+const schema2 = new Schema({ name: 'String' }); // Equivalent
+
+const Person = mongoose.model('Person', schema2);
+```
+
+If you pass an element that has a `toString()` function, Mongoose will call it,
+unless the element is an array or the `toString()` function is strictly equal to
+`Object.prototype.toString()`.
+
+```javascript
+new Person({ name: 42 }).name; // "42" as a string
+new Person({ name: { toString: () => 42 } }).name; // "42" as a string
+
+// "undefined", will get a cast error if you `save()` this document
+new Person({ name: { foo: 42 } }).name;
+```
+
+<h4 id="numbers">Number</h4>
+
+To declare a path as a number, you may use either the `Number` global
+constructor or the string `'Number'`.
+
+```javascript
+const schema1 = new Schema({ age: Number }); // age will be cast to a Number
+const schema2 = new Schema({ age: 'Number' }); // Equivalent
+
+const Car = mongoose.model('Car', schema2);
+```
+
+There are several types of values that will be successfully cast to a Number.
+
+```javascript
+new Car({ age: '15' }).age; // 15 as a Number
+new Car({ age: true }).age; // 1 as a Number
+new Car({ age: false }).age; // 0 as a Number
+new Car({ age: { valueOf: () => 83 } }).age; // 83 as a Number
+```
+
+If you pass an object with a `valueOf()` function that returns a Number, Mongoose will
+call it and assign the returned value to the path.
+
+The values `null` and `undefined` are not cast.
+
+NaN, strings that cast to NaN, arrays, and objects that don't have a `valueOf()` function
+will all result in a [CastError](/docs/validation.html#cast-errors) once validated, meaning that it will not throw on initialization, only when validated.
+
+<h4 id="dates">Dates</h4>
+
+[Built-in `Date` methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date) are [__not__ hooked into](https://github.com/Automattic/mongoose/issues/1598) the mongoose change tracking logic which in English means that if you use a `Date` in your document and modify it with a method like `setMonth()`, mongoose will be unaware of this change and `doc.save()` will not persist this modification. If you must modify `Date` types using built-in methods, tell mongoose about the change with `doc.markModified('pathToYourDate')` before saving.
+
+```javascript
+const Assignment = mongoose.model('Assignment', { dueDate: Date });
+Assignment.findOne(function (err, doc) {
+  doc.dueDate.setMonth(3);
+  doc.save(callback); // THIS DOES NOT SAVE YOUR CHANGE
+
+  doc.markModified('dueDate');
+  doc.save(callback); // works
+})
+```
+
+<h4 id="buffers">Buffer</h4>
+
+To declare a path as a Buffer, you may use either the `Buffer` global
+constructor or the string `'Buffer'`.
+
+```javascript
+const schema1 = new Schema({ binData: Buffer }); // binData will be cast to a Buffer
+const schema2 = new Schema({ binData: 'Buffer' }); // Equivalent
+
+const Data = mongoose.model('Data', schema2);
+```
+
+Mongoose will successfully cast the below values to buffers.
+
+```
+const file1 = new Data({ binData: 'test'}); // {"type":"Buffer","data":[116,101,115,116]}
+const file2 = new Data({ binData: 72987 }); // {"type":"Buffer","data":[27]}
+const file4 = new Data({ binData: { type: 'Buffer', data: [1, 2, 3]}}); // {"type":"Buffer","data":[1,2,3]}
+```
+
+<h4 id="mixed">Mixed</h4>
+
+An "anything goes" SchemaType. Mongoose will not do any casting on mixed paths.
+You can define a mixed path using `Schema.Types.Mixed` or by passing an empty
+object literal. The following are equivalent.
+
+```javascript
+const Any = new Schema({ any: {} });
+const Any = new Schema({ any: Object });
+const Any = new Schema({ any: Schema.Types.Mixed });
+const Any = new Schema({ any: mongoose.Mixed });
+// Note that by default, if you're using `type`, putting _any_ POJO as the `type` will
+// make the path mixed.
+const Any = new Schema({
+  any: {
+    type: { foo: String }
+  } // "any" will be Mixed - everything inside is ignored.
+});
+// However, as of Mongoose 5.8.0, this behavior can be overridden with typePojoToMixed.
+// In that case, it will create a single nested subdocument type instead.
+const Any = new Schema({
+  any: {
+    type: { foo: String }
+  } // "any" will be a single nested subdocument.
+}, {typePojoToMixed: false});
+```
+
+Since Mixed is a schema-less type, you can change the value to anything else you
+like, but Mongoose loses the ability to auto detect and save those changes.
+To tell Mongoose that the value of a Mixed type has changed, you need to
+call `doc.markModified(path)`, passing the path to the Mixed type you just changed.
+
+To avoid these side-effects, a [Subdocument](./subdocs.html) path may be used
+instead.
+
+```javascript
+person.anything = { x: [3, 4, { y: "changed" }] };
+person.markModified('anything');
+person.save(); // Mongoose will save changes to `anything`.
+```
+
+<h4 id="objectids">ObjectIds</h4>
+
+An [ObjectId](https://docs.mongodb.com/manual/reference/method/ObjectId/)
+is a special type typically used for unique identifiers. Here's how
+you declare a schema with a path `driver` that is an ObjectId:
+
+```javascript
+const mongoose = require('mongoose');
+const carSchema = new mongoose.Schema({ driver: mongoose.ObjectId });
+```
+
+`ObjectId` is a class, and ObjectIds are objects. However, they are
+often represented as strings. When you convert an ObjectId to a string
+using `toString()`, you get a 24-character hexadecimal string:
+
+```javascript
+const Car = mongoose.model('Car', carSchema);
+
+const car = new Car();
+car.driver = new mongoose.Types.ObjectId();
+
+typeof car.driver; // 'object'
+car.driver instanceof mongoose.Types.ObjectId; // true
+
+car.driver.toString(); // Something like "5e1a0651741b255ddda996c4"
+```
+
+<h4 id="booleans">Boolean</h4>
+
+Booleans in Mongoose are [plain JavaScript booleans](https://www.w3schools.com/js/js_booleans.asp).
+By default, Mongoose casts the below values to `true`:
+
+* `true`
+* `'true'`
+* `1`
+* `'1'`
+* `'yes'`
+
+Mongoose casts the below values to `false`:
+
+* `false`
+* `'false'`
+* `0`
+* `'0'`
+* `'no'`
+
+Any other value causes a [CastError](/docs/validation.html#cast-errors).
+You can modify what values Mongoose converts to true or false using the
+`convertToTrue` and `convertToFalse` properties, which are [JavaScript sets](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set).
+
+```javascript
+const M = mongoose.model('Test', new Schema({ b: Boolean }));
+console.log(new M({ b: 'nay' }).b); // undefined
+
+// Set { false, 'false', 0, '0', 'no' }
+console.log(mongoose.Schema.Types.Boolean.convertToFalse);
+
+mongoose.Schema.Types.Boolean.convertToFalse.add('nay');
+console.log(new M({ b: 'nay' }).b); // false
+```
+
+<h4 id="arrays">Arrays</h4>
+
+Mongoose supports arrays of [SchemaTypes](./api.html#schema_Schema.Types)
+and arrays of [subdocuments](./subdocs.html). Arrays of SchemaTypes are
+also called _primitive arrays_, and arrays of subdocuments are also called
+_document arrays_.
+
+```javascript
+const ToySchema = new Schema({ name: String });
+const ToyBoxSchema = new Schema({
+  toys: [ToySchema],
+  buffers: [Buffer],
+  strings: [String],
+  numbers: [Number]
+  // ... etc
+});
+```
+
+Arrays are special because they implicitly have a default value of `[]` (empty array).
+
+```javascript
+const ToyBox = mongoose.model('ToyBox', ToyBoxSchema);
+console.log((new ToyBox()).toys); // []
+```
+
+To overwrite this default, you need to set the default value to `undefined`
+
+```javascript
+const ToyBoxSchema = new Schema({
+  toys: {
+    type: [ToySchema],
+    default: undefined
+  }
+});
+```
+
+Note: specifying an empty array is equivalent to `Mixed`. The following all create arrays of
+`Mixed`:
+
+```javascript
+const Empty1 = new Schema({ any: [] });
+const Empty2 = new Schema({ any: Array });
+const Empty3 = new Schema({ any: [Schema.Types.Mixed] });
+const Empty4 = new Schema({ any: [{}] });
+```
+
+<h4 id="maps">Maps</h4>
+
+_New in Mongoose 5.1.0_
+
+A `MongooseMap` is a subclass of [JavaScript's `Map` class](http://thecodebarbarian.com/the-80-20-guide-to-maps-in-javascript.html).
+In these docs, we'll use the terms 'map' and `MongooseMap` interchangeably.
+In Mongoose, maps are how you create a nested document with arbitrary keys.
+
+**Note**: In Mongoose Maps, keys must be strings in order to store the document in MongoDB.
+
+```javascript
+const userSchema = new Schema({
+  // `socialMediaHandles` is a map whose values are strings. A map's
+  // keys are always strings. You specify the type of values using `of`.
+  socialMediaHandles: {
+    type: Map,
+    of: String
+  }
+});
+
+const User = mongoose.model('User', userSchema);
+// Map { 'github' => 'vkarpov15', 'twitter' => '@code_barbarian' }
+console.log(new User({
+  socialMediaHandles: {
+    github: 'vkarpov15',
+    twitter: '@code_barbarian'
+  }
+}).socialMediaHandles);
+```
+
+The above example doesn't explicitly declare `github` or `twitter` as paths,
+but, since `socialMediaHandles` is a map, you can store arbitrary key/value
+pairs. However, since `socialMediaHandles` is a map, you **must** use
+`.get()` to get the value of a key and `.set()` to set the value of a key.
+
+```javascript
+const user = new User({
+  socialMediaHandles: {}
+});
+
+// Good
+user.socialMediaHandles.set('github', 'vkarpov15');
+// Works too
+user.set('socialMediaHandles.twitter', '@code_barbarian');
+// Bad, the `myspace` property will **not** get saved
+user.socialMediaHandles.myspace = 'fail';
+
+// 'vkarpov15'
+console.log(user.socialMediaHandles.get('github'));
+// '@code_barbarian'
+console.log(user.get('socialMediaHandles.twitter'));
+// undefined
+user.socialMediaHandles.github;
+
+// Will only save the 'github' and 'twitter' properties
+user.save();
+```
+
+Map types are stored as [BSON objects in MongoDB](https://en.wikipedia.org/wiki/BSON#Data_types_and_syntax).
+Keys in a BSON object are ordered, so this means the [insertion order](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#Description)
+property of maps is maintained.
+
+Mongoose supports a special `$*` syntax to [populate](/docs/populate.html) all elements in a map.
+For example, suppose your `socialMediaHandles` map contains a `ref`:
+
+```javascript
+const userSchema = new Schema({
+  socialMediaHandles: {
+    type: Map,
+    of: new Schema({
+      handle: String,
+      oauth: {
+        type: ObjectId,
+        ref: 'OAuth'
+      }
+    })
+  }
+});
+const User = mongoose.model('User', userSchema);
+```
+
+To populate every `socialMediaHandles` entry's `oauth` property, you should populate
+on `socialMediaHandles.$*.oauth`:
+
+```javascript
+const user = await User.findOne().populate('socialMediaHandles.$*.oauth');
+```
+
+<h3 id="getters"><a href="#getters">Getters</a></h3>
+
+Getters are like virtuals for paths defined in your schema. For example,
+let's say you wanted to store user profile pictures as relative paths and
+then add the hostname in your application. Below is how you would structure
+your `userSchema`:
+
+```javascript
+const root = 'https://s3.amazonaws.com/mybucket';
+
+const userSchema = new Schema({
+  name: String,
+  picture: {
+    type: String,
+    get: v => `${root}${v}`
+  }
+});
+
+const User = mongoose.model('User', userSchema);
+
+const doc = new User({ name: 'Val', picture: '/123.png' });
+doc.picture; // 'https://s3.amazonaws.com/mybucket/123.png'
+doc.toObject({ getters: false }).picture; // '/123.png'
+```
+
+Generally, you only use getters on primitive paths as opposed to arrays
+or subdocuments. Because getters override what accessing a Mongoose path returns,
+declaring a getter on an object may remove Mongoose change tracking for
+that path.
+
+```javascript
+const schema = new Schema({
+  arr: [{ url: String }]
+});
+
+const root = 'https://s3.amazonaws.com/mybucket';
+
+// Bad, don't do this!
+schema.path('arr').get(v => {
+  return v.map(el => Object.assign(el, { url: root + el.url }));
+});
+
+// Later
+doc.arr.push({ key: String });
+doc.arr[0]; // 'undefined' because every `doc.arr` creates a new array!
+```
+
+Instead of declaring a getter on the array as shown above, you should
+declare a getter on the `url` string as shown below. If you need to declare
+a getter on a nested document or array, be very careful!
+
+```javascript
+const schema = new Schema({
+  arr: [{ url: String }]
+});
+
+const root = 'https://s3.amazonaws.com/mybucket';
+
+// Good, do this instead of declaring a getter on `arr`
+schema.path('arr.0.url').get(v => `${root}${v}`);
+```
+
+<h3 id="schemas"><a href="#schemas">Schemas</a></h3>
+
+To declare a path as another [schema](./guide.html#definition),
+set `type` to the sub-schema's instance.
+
+To set a default value based on the sub-schema's shape, simply set a default value,
+and the value will be cast based on the sub-schema's definition before being set
+during document creation.
+
+```javascript
+const subSchema = new mongoose.Schema({
+  // some schema definition here
+});
+
+const schema = new mongoose.Schema({
+  data: {
+    type: subSchema
+    default: {}
+  }
+});
+```
+
+<h3 id="customtypes"><a href="#customtypes">Creating Custom Types</a></h3>
+
+Mongoose can also be extended with [custom SchemaTypes](customschematypes.html). Search the
+[plugins](http://plugins.mongoosejs.io)
+site for compatible types like
+[mongoose-long](https://github.com/aheckmann/mongoose-long),
+[mongoose-int32](https://github.com/vkarpov15/mongoose-int32),
+and
+[other](https://github.com/aheckmann/mongoose-function)
+[types](https://github.com/OpenifyIt/mongoose-types).
+
+Read more about creating [custom SchemaTypes here](customschematypes.html).
+
+<h3 id="path"><a href="#path">The `schema.path()` Function</a></h3>
+
+The `schema.path()` function returns the instantiated schema type for a
+given path.
+
+```javascript
+const sampleSchema = new Schema({ name: { type: String, required: true } });
+console.log(sampleSchema.path('name'));
+// Output looks like:
+/**
+ * SchemaString {
+ *   enumValues: [],
+  *   regExp: null,
+  *   path: 'name',
+  *   instance: 'String',
+  *   validators: ...
+  */
+  ```
+
+You can use this function to inspect the schema type for a given path,
+including what validators it has and what the type is.
+
+<h3 id="further-reading"><a href="#further-reading">Further Reading</a></h3>
+
+<ul>
+  <li><a href="https://masteringjs.io/tutorials/mongoose/schematype">An Introduction to Mongoose SchemaTypes</a></li>
+  <li><a href="https://kb.objectrocket.com/mongo-db/mongoose-schema-types-1418">Mongoose Schema Types</a></li>
+</ul>
diff --git a/docs/schematypes.pug b/docs/schematypes.pug
deleted file mode 100644
index 7734c958929..00000000000
--- a/docs/schematypes.pug
+++ /dev/null
@@ -1,761 +0,0 @@
-extends layout
-
-block append style
-  link(rel="stylesheet", href="/docs/css/inlinecpc.css")
-  script(type="text/javascript" src="/docs/js/native.js")
-
-block content
-  <a class="edit-docs-link" href="#{editLink}" target="_blank">
-    <img src="/docs/images/pencil.svg" />
-  </a>
-
-  :markdown
-    <h2 id="schematypes"><a href="#schematypes">SchemaTypes</a></h2>
-
-    <script>
-      _native.init("CK7DT53U",{
-        targetClass: 'native-inline'
-      });
-    </script>
-
-    <div class="native-inline">
-      <a href="#native_link#"><span class="sponsor">Sponsor</span> #native_company# — #native_desc#</a>
-    </div>
-
-    SchemaTypes handle definition of path
-    [defaults](./api.html#schematype_SchemaType-default),
-    [validation](./api.html#schematype_SchemaType-validate),
-    [getters](#getters),
-    [setters](./api.html#schematype_SchemaType-set),
-    [field selection defaults](./api.html#schematype_SchemaType-select) for
-    [queries](./api.html#query-js),
-    and other general characteristics for Mongoose document properties.
-
-    <ul class="toc">
-      <li><a href="#what-is-a-schema-type">What is a SchemaType?</a></li>
-      <li><a href="#schematype-options">SchemaType Options</a></li>
-      <li><a href="#customtypes">Creating Custom Types</a></li>
-      <li><a href="#path">The `schema.path()` Function</a></li>
-      <li><a href="#further-reading">Further Reading</a></li>
-    </ul>
-
-    * [What is a SchemaType?](#what-is-a-schematype)
-    * [The `type` Key](#type-key)
-    * [SchemaType Options](#schematype-options)
-    * [Usage Notes](#usage-notes)
-    * [Getters](#getters)
-    * [Custom Types](#customtypes)
-    * [The `schema.path()` Function](#path)
-
-    <h3 id="what-is-a-schematype"><a href="#what-is-a-schematype">What is a SchemaType?</a></h3>
-
-    You can think of a Mongoose schema as the configuration object for a
-    Mongoose model. A SchemaType is then a configuration object for an individual
-    property. A SchemaType says what type a given
-    path should have, whether it has any getters/setters, and what values are
-    valid for that path.
-
-    ```javascript
-    const schema = new Schema({ name: String });
-    schema.path('name') instanceof mongoose.SchemaType; // true
-    schema.path('name') instanceof mongoose.Schema.Types.String; // true
-    schema.path('name').instance; // 'String'
-    ```
-
-    A SchemaType is different from a type. In other words, `mongoose.ObjectId !== mongoose.Types.ObjectId`.
-    A SchemaType is just a configuration object for Mongoose. An instance of
-    the `mongoose.ObjectId` SchemaType doesn't actually create MongoDB ObjectIds,
-    it is just a configuration for a path in a schema.
-
-    The following are all the valid SchemaTypes in Mongoose. Mongoose plugins
-    can also add custom SchemaTypes like [int32](http://plugins.mongoosejs.io/plugins/int32).
-    Check out [Mongoose's plugins search](http://plugins.mongoosejs.io) to find plugins.
-
-    - [String](#strings)
-    - [Number](#numbers)
-    - [Date](#dates)
-    - [Buffer](#buffers)
-    - [Boolean](#booleans)
-    - [Mixed](#mixed)
-    - [ObjectId](#objectids)
-    - [Array](#arrays)
-    - [Decimal128](./api.html#mongoose_Mongoose-Decimal128)
-    - [Map](#maps)
-    - [Schema](#schemas)
-
-    <h4>Example</h4>
-
-    ```javascript
-    const schema = new Schema({
-      name:    String,
-      binary:  Buffer,
-      living:  Boolean,
-      updated: { type: Date, default: Date.now },
-      age:     { type: Number, min: 18, max: 65 },
-      mixed:   Schema.Types.Mixed,
-      _someId: Schema.Types.ObjectId,
-      decimal: Schema.Types.Decimal128,
-      array: [],
-      ofString: [String],
-      ofNumber: [Number],
-      ofDates: [Date],
-      ofBuffer: [Buffer],
-      ofBoolean: [Boolean],
-      ofMixed: [Schema.Types.Mixed],
-      ofObjectId: [Schema.Types.ObjectId],
-      ofArrays: [[]],
-      ofArrayOfNumbers: [[Number]],
-      nested: {
-        stuff: { type: String, lowercase: true, trim: true }
-      },
-      map: Map,
-      mapOfString: {
-        type: Map,
-        of: String
-      }
-    })
-
-    // example use
-
-    const Thing = mongoose.model('Thing', schema);
-
-    const m = new Thing;
-    m.name = 'Statue of Liberty';
-    m.age = 125;
-    m.updated = new Date;
-    m.binary = Buffer.alloc(0);
-    m.living = false;
-    m.mixed = { any: { thing: 'i want' } };
-    m.markModified('mixed');
-    m._someId = new mongoose.Types.ObjectId;
-    m.array.push(1);
-    m.ofString.push("strings!");
-    m.ofNumber.unshift(1,2,3,4);
-    m.ofDates.addToSet(new Date);
-    m.ofBuffer.pop();
-    m.ofMixed = [1, [], 'three', { four: 5 }];
-    m.nested.stuff = 'good';
-    m.map = new Map([['key', 'value']]);
-    m.save(callback);
-    ```
-
-    <h3 id="type-key"><a href="#type-key">The `type` Key</a></h3>
-
-    `type` is a special property in Mongoose schemas. When Mongoose finds
-    a nested property named `type` in your schema, Mongoose assumes that
-    it needs to define a SchemaType with the given type.
-
-    ```javascript
-    // 3 string SchemaTypes: 'name', 'nested.firstName', 'nested.lastName'
-    const schema = new Schema({
-      name: { type: String },
-      nested: {
-        firstName: { type: String },
-        lastName: { type: String }
-      }
-    });
-    ```
-
-    As a consequence, [you need a little extra work to define a property named `type` in your schema](/docs/faq.html#type-key).
-    For example, suppose you're building a stock portfolio app, and you
-    want to store the asset's `type` (stock, bond, ETF, etc.). Naively,
-    you might define your schema as shown below:
-
-    ```javascript
-    const holdingSchema = new Schema({
-      // You might expect `asset` to be an object that has 2 properties,
-      // but unfortunately `type` is special in Mongoose so mongoose
-      // interprets this schema to mean that `asset` is a string
-      asset: {
-        type: String,
-        ticker: String
-      }
-    });
-    ```
-
-    However, when Mongoose sees `type: String`, it assumes that you mean
-    `asset` should be a string, not an object with a property `type`.
-    The correct way to define an object with a property `type` is shown
-    below.
-
-    ```javascript
-    const holdingSchema = new Schema({
-      asset: {
-        // Workaround to make sure Mongoose knows `asset` is an object
-        // and `asset.type` is a string, rather than thinking `asset`
-        // is a string.
-        type: { type: String },
-        ticker: String
-      }
-    });
-    ```
-
-    <h3 id="schematype-options"><a href="#schematype-options">SchemaType Options</a></h3>
-
-    You can declare a schema type using the type directly, or an object with
-    a `type` property.
-
-    ```javascript
-    const schema1 = new Schema({
-      test: String // `test` is a path of type String
-    });
-
-    const schema2 = new Schema({
-      // The `test` object contains the "SchemaType options"
-      test: { type: String } // `test` is a path of type string
-    });
-    ```
-
-    In addition to the type property, you can specify additional properties
-    for a path. For example, if you want to lowercase a string before saving:
-
-    ```javascript
-    const schema2 = new Schema({
-      test: {
-        type: String,
-        lowercase: true // Always convert `test` to lowercase
-      }
-    });
-    ```
-
-    You can add any property you want to your SchemaType options. Many plugins
-    rely on custom SchemaType options. For example, the [mongoose-autopopulate](http://plugins.mongoosejs.io/plugins/autopopulate)
-    plugin automatically populates paths if you set `autopopulate: true` in your
-    SchemaType options. Mongoose comes with support for several built-in
-    SchemaType options, like `lowercase` in the above example.
-
-    The `lowercase` option only works for strings. There are certain options
-    which apply for all schema types, and some that apply for specific schema
-    types.
-
-    <h5>All Schema Types</h5>
-
-    * `required`: boolean or function, if true adds a [required validator](./validation.html#built-in-validators) for this property
-    * `default`: Any or function, sets a default value for the path. If the value is a function, the return value of the function is used as the default.
-    * `select`: boolean, specifies default [projections](https://docs.mongodb.com/manual/tutorial/project-fields-from-query-results/) for queries
-    * `validate`: function, adds a [validator function](./validation.html#built-in-validators) for this property
-    * `get`: function, defines a custom getter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
-    * `set`: function, defines a custom setter for this property using [`Object.defineProperty()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty).
-    * `alias`: string, mongoose >= 4.10.0 only. Defines a [virtual](./guide.html#virtuals) with the given name that gets/sets this path.
-    * `immutable`: boolean, defines path as immutable. Mongoose prevents you from changing immutable paths unless the parent document has `isNew: true`.
-    * `transform`: function, Mongoose calls this function when you call [`Document#toJSON()`](/docs/api/document.html#document_Document-toJSON) function, including when you [`JSON.stringify()`](https://thecodebarbarian.com/the-80-20-guide-to-json-stringify-in-javascript) a document.
-
-    ```javascript
-    const numberSchema = new Schema({
-      integerOnly: {
-        type: Number,
-        get: v => Math.round(v),
-        set: v => Math.round(v),
-        alias: 'i'
-      }
-    });
-
-    const Number = mongoose.model('Number', numberSchema);
-
-    const doc = new Number();
-    doc.integerOnly = 2.001;
-    doc.integerOnly; // 2
-    doc.i; // 2
-    doc.i = 3.001;
-    doc.integerOnly; // 3
-    doc.i; // 3
-    ```
-
-    <h5>Indexes</h5>
-
-    You can also define [MongoDB indexes](https://docs.mongodb.com/manual/indexes/)
-    using schema type options.
-
-    * `index`: boolean, whether to define an [index](https://docs.mongodb.com/manual/indexes/) on this property.
-    * `unique`: boolean, whether to define a [unique index](https://docs.mongodb.com/manual/core/index-unique/) on this property.
-    * `sparse`: boolean, whether to define a [sparse index](https://docs.mongodb.com/manual/core/index-sparse/) on this property.
-
-    ```javascript
-    const schema2 = new Schema({
-      test: {
-        type: String,
-        index: true,
-        unique: true // Unique index. If you specify `unique: true`
-        // specifying `index: true` is optional if you do `unique: true`
-      }
-    });
-    ```
-
-    <h5 id="string-validators">String</h5>
-
-    * `lowercase`: boolean, whether to always call `.toLowerCase()` on the value
-    * `uppercase`: boolean, whether to always call `.toUpperCase()` on the value
-    * `trim`: boolean, whether to always call `.trim()` on the value
-    * `match`: RegExp, creates a [validator](./validation.html) that checks if the value matches the given regular expression
-    * `enum`: Array, creates a [validator](./validation.html) that checks if the value is in the given array.
-    * `minLength`: Number, creates a [validator](./validation.html) that checks if the value length is not less than the given number
-    * `maxLength`: Number, creates a [validator](./validation.html) that checks if the value length is not greater than the given number
-    * `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
-
-    <h5 id="number-validators">Number</h5>
-
-    * `min`: Number, creates a [validator](./validation.html) that checks if the value is greater than or equal to the given minimum.
-    * `max`: Number, creates a [validator](./validation.html) that checks if the value is less than or equal to the given maximum.
-    * `enum`: Array, creates a [validator](./validation.html) that checks if the value is strictly equal to one of the values in the given array.
-    * `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
-
-    <h5>Date</h5>
-
-    * `min`: Date
-    * `max`: Date
-
-    <h5>ObjectId</h5>
-
-    * `populate`: Object, sets default [populate options](/docs/populate.html#query-conditions)
-
-    <h3 id="usage-notes"><a href="#usage-notes">Usage Notes</a></h3>
-
-    <h4 id="strings">String</h4>
-
-    To declare a path as a string, you may use either the `String` global
-    constructor or the string `'String'`.
-
-    ```javascript
-    const schema1 = new Schema({ name: String }); // name will be cast to string
-    const schema2 = new Schema({ name: 'String' }); // Equivalent
-
-    const Person = mongoose.model('Person', schema2);
-    ```
-
-    If you pass an element that has a `toString()` function, Mongoose will call it,
-    unless the element is an array or the `toString()` function is strictly equal to
-    `Object.prototype.toString()`.
-
-    ```javascript
-    new Person({ name: 42 }).name; // "42" as a string
-    new Person({ name: { toString: () => 42 } }).name; // "42" as a string
-
-    // "undefined", will get a cast error if you `save()` this document
-    new Person({ name: { foo: 42 } }).name;
-    ```
-
-    <h4 id="numbers">Number</h4>
-
-    To declare a path as a number, you may use either the `Number` global
-    constructor or the string `'Number'`.
-
-    ```javascript
-    const schema1 = new Schema({ age: Number }); // age will be cast to a Number
-    const schema2 = new Schema({ age: 'Number' }); // Equivalent
-
-    const Car = mongoose.model('Car', schema2);
-    ```
-
-    There are several types of values that will be successfully cast to a Number.
-
-    ```javascript
-    new Car({ age: '15' }).age; // 15 as a Number
-    new Car({ age: true }).age; // 1 as a Number
-    new Car({ age: false }).age; // 0 as a Number
-    new Car({ age: { valueOf: () => 83 } }).age; // 83 as a Number
-    ```
-
-    If you pass an object with a `valueOf()` function that returns a Number, Mongoose will
-    call it and assign the returned value to the path.
-
-    The values `null` and `undefined` are not cast.
-
-    NaN, strings that cast to NaN, arrays, and objects that don't have a `valueOf()` function
-    will all result in a [CastError](/docs/validation.html#cast-errors) once validated, meaning that it will not throw on initialization, only when validated.
-
-    <h4 id="dates">Dates</h4>
-
-    [Built-in `Date` methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date) are [__not__ hooked into](https://github.com/Automattic/mongoose/issues/1598) the mongoose change tracking logic which in English means that if you use a `Date` in your document and modify it with a method like `setMonth()`, mongoose will be unaware of this change and `doc.save()` will not persist this modification. If you must modify `Date` types using built-in methods, tell mongoose about the change with `doc.markModified('pathToYourDate')` before saving.
-
-    ```javascript
-    const Assignment = mongoose.model('Assignment', { dueDate: Date });
-    Assignment.findOne(function (err, doc) {
-      doc.dueDate.setMonth(3);
-      doc.save(callback); // THIS DOES NOT SAVE YOUR CHANGE
-
-      doc.markModified('dueDate');
-      doc.save(callback); // works
-    })
-    ```
-
-    <h4 id="buffers">Buffer</h4>
-
-    To declare a path as a Buffer, you may use either the `Buffer` global
-    constructor or the string `'Buffer'`.
-
-    ```javascript
-    const schema1 = new Schema({ binData: Buffer }); // binData will be cast to a Buffer
-    const schema2 = new Schema({ binData: 'Buffer' }); // Equivalent
-
-    const Data = mongoose.model('Data', schema2);
-    ```
-
-    Mongoose will successfully cast the below values to buffers.
-
-    ```
-    const file1 = new Data({ binData: 'test'}); // {"type":"Buffer","data":[116,101,115,116]}
-    const file2 = new Data({ binData: 72987 }); // {"type":"Buffer","data":[27]}
-    const file4 = new Data({ binData: { type: 'Buffer', data: [1, 2, 3]}}); // {"type":"Buffer","data":[1,2,3]}
-    ```
-
-    <h4 id="mixed">Mixed</h4>
-
-    An "anything goes" SchemaType. Mongoose will not do any casting on mixed paths.
-    You can define a mixed path using `Schema.Types.Mixed` or by passing an empty
-    object literal. The following are equivalent.
-
-    ```javascript
-    const Any = new Schema({ any: {} });
-    const Any = new Schema({ any: Object });
-    const Any = new Schema({ any: Schema.Types.Mixed });
-    const Any = new Schema({ any: mongoose.Mixed });
-    // Note that by default, if you're using `type`, putting _any_ POJO as the `type` will
-    // make the path mixed.
-    const Any = new Schema({
-      any: {
-        type: { foo: String }
-      } // "any" will be Mixed - everything inside is ignored.
-    });
-    // However, as of Mongoose 5.8.0, this behavior can be overridden with typePojoToMixed.
-    // In that case, it will create a single nested subdocument type instead.
-    const Any = new Schema({
-      any: {
-        type: { foo: String }
-      } // "any" will be a single nested subdocument.
-    }, {typePojoToMixed: false});
-    ```
-
-    Since Mixed is a schema-less type, you can change the value to anything else you
-    like, but Mongoose loses the ability to auto detect and save those changes.
-    To tell Mongoose that the value of a Mixed type has changed, you need to
-    call `doc.markModified(path)`, passing the path to the Mixed type you just changed.
-
-    To avoid these side-effects, a [Subdocument](./subdocs.html) path may be used
-    instead.
-
-    ```javascript
-    person.anything = { x: [3, 4, { y: "changed" }] };
-    person.markModified('anything');
-    person.save(); // Mongoose will save changes to `anything`.
-    ```
-
-    <h4 id="objectids">ObjectIds</h4>
-
-    An [ObjectId](https://docs.mongodb.com/manual/reference/method/ObjectId/)
-    is a special type typically used for unique identifiers. Here's how
-    you declare a schema with a path `driver` that is an ObjectId:
-
-    ```javascript
-    const mongoose = require('mongoose');
-    const carSchema = new mongoose.Schema({ driver: mongoose.ObjectId });
-    ```
-
-    `ObjectId` is a class, and ObjectIds are objects. However, they are
-    often represented as strings. When you convert an ObjectId to a string
-    using `toString()`, you get a 24-character hexadecimal string:
-
-    ```javascript
-    const Car = mongoose.model('Car', carSchema);
-
-    const car = new Car();
-    car.driver = new mongoose.Types.ObjectId();
-
-    typeof car.driver; // 'object'
-    car.driver instanceof mongoose.Types.ObjectId; // true
-
-    car.driver.toString(); // Something like "5e1a0651741b255ddda996c4"
-    ```
-
-    <h4 id="booleans">Boolean</h4>
-
-    Booleans in Mongoose are [plain JavaScript booleans](https://www.w3schools.com/js/js_booleans.asp).
-    By default, Mongoose casts the below values to `true`:
-
-    * `true`
-    * `'true'`
-    * `1`
-    * `'1'`
-    * `'yes'`
-
-    Mongoose casts the below values to `false`:
-
-    * `false`
-    * `'false'`
-    * `0`
-    * `'0'`
-    * `'no'`
-
-    Any other value causes a [CastError](/docs/validation.html#cast-errors).
-    You can modify what values Mongoose converts to true or false using the
-    `convertToTrue` and `convertToFalse` properties, which are [JavaScript sets](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set).
-
-    ```javascript
-    const M = mongoose.model('Test', new Schema({ b: Boolean }));
-    console.log(new M({ b: 'nay' }).b); // undefined
-
-    // Set { false, 'false', 0, '0', 'no' }
-    console.log(mongoose.Schema.Types.Boolean.convertToFalse);
-
-    mongoose.Schema.Types.Boolean.convertToFalse.add('nay');
-    console.log(new M({ b: 'nay' }).b); // false
-    ```
-
-    <h4 id="arrays">Arrays</h4>
-
-    Mongoose supports arrays of [SchemaTypes](./api.html#schema_Schema.Types)
-    and arrays of [subdocuments](./subdocs.html). Arrays of SchemaTypes are
-    also called _primitive arrays_, and arrays of subdocuments are also called
-    _document arrays_.
-
-    ```javascript
-    const ToySchema = new Schema({ name: String });
-    const ToyBoxSchema = new Schema({
-      toys: [ToySchema],
-      buffers: [Buffer],
-      strings: [String],
-      numbers: [Number]
-      // ... etc
-    });
-    ```
-
-    Arrays are special because they implicitly have a default value of `[]` (empty array).
-
-    ```javascript
-    const ToyBox = mongoose.model('ToyBox', ToyBoxSchema);
-    console.log((new ToyBox()).toys); // []
-    ```
-
-    To overwrite this default, you need to set the default value to `undefined`
-
-    ```javascript
-    const ToyBoxSchema = new Schema({
-      toys: {
-        type: [ToySchema],
-        default: undefined
-      }
-    });
-    ```
-
-    Note: specifying an empty array is equivalent to `Mixed`. The following all create arrays of
-    `Mixed`:
-
-    ```javascript
-    const Empty1 = new Schema({ any: [] });
-    const Empty2 = new Schema({ any: Array });
-    const Empty3 = new Schema({ any: [Schema.Types.Mixed] });
-    const Empty4 = new Schema({ any: [{}] });
-    ```
-
-    <h4 id="maps">Maps</h4>
-
-    _New in Mongoose 5.1.0_
-
-    A `MongooseMap` is a subclass of [JavaScript's `Map` class](http://thecodebarbarian.com/the-80-20-guide-to-maps-in-javascript.html).
-    In these docs, we'll use the terms 'map' and `MongooseMap` interchangeably.
-    In Mongoose, maps are how you create a nested document with arbitrary keys.
-
-    **Note**: In Mongoose Maps, keys must be strings in order to store the document in MongoDB.
-
-    ```javascript
-    const userSchema = new Schema({
-      // `socialMediaHandles` is a map whose values are strings. A map's
-      // keys are always strings. You specify the type of values using `of`.
-      socialMediaHandles: {
-        type: Map,
-        of: String
-      }
-    });
-
-    const User = mongoose.model('User', userSchema);
-    // Map { 'github' => 'vkarpov15', 'twitter' => '@code_barbarian' }
-    console.log(new User({
-      socialMediaHandles: {
-        github: 'vkarpov15',
-        twitter: '@code_barbarian'
-      }
-    }).socialMediaHandles);
-    ```
-
-    The above example doesn't explicitly declare `github` or `twitter` as paths,
-    but, since `socialMediaHandles` is a map, you can store arbitrary key/value
-    pairs. However, since `socialMediaHandles` is a map, you **must** use
-    `.get()` to get the value of a key and `.set()` to set the value of a key.
-
-    ```javascript
-    const user = new User({
-      socialMediaHandles: {}
-    });
-
-    // Good
-    user.socialMediaHandles.set('github', 'vkarpov15');
-    // Works too
-    user.set('socialMediaHandles.twitter', '@code_barbarian');
-    // Bad, the `myspace` property will **not** get saved
-    user.socialMediaHandles.myspace = 'fail';
-
-    // 'vkarpov15'
-    console.log(user.socialMediaHandles.get('github'));
-    // '@code_barbarian'
-    console.log(user.get('socialMediaHandles.twitter'));
-    // undefined
-    user.socialMediaHandles.github;
-
-    // Will only save the 'github' and 'twitter' properties
-    user.save();
-    ```
-
-    Map types are stored as [BSON objects in MongoDB](https://en.wikipedia.org/wiki/BSON#Data_types_and_syntax).
-    Keys in a BSON object are ordered, so this means the [insertion order](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#Description)
-    property of maps is maintained.
-
-    Mongoose supports a special `$*` syntax to [populate](/docs/populate.html) all elements in a map.
-    For example, suppose your `socialMediaHandles` map contains a `ref`:
-
-    ```javascript
-    const userSchema = new Schema({
-      socialMediaHandles: {
-        type: Map,
-        of: new Schema({
-          handle: String,
-          oauth: {
-            type: ObjectId,
-            ref: 'OAuth'
-          }
-        })
-      }
-    });
-    const User = mongoose.model('User', userSchema);
-    ```
-
-    To populate every `socialMediaHandles` entry's `oauth` property, you should populate
-    on `socialMediaHandles.$*.oauth`:
-
-    ```javascript
-    const user = await User.findOne().populate('socialMediaHandles.$*.oauth');
-    ```
-
-    <h3 id="getters"><a href="#getters">Getters</a></h3>
-
-    Getters are like virtuals for paths defined in your schema. For example,
-    let's say you wanted to store user profile pictures as relative paths and
-    then add the hostname in your application. Below is how you would structure
-    your `userSchema`:
-
-    ```javascript
-    const root = 'https://s3.amazonaws.com/mybucket';
-
-    const userSchema = new Schema({
-      name: String,
-      picture: {
-        type: String,
-        get: v => `${root}${v}`
-      }
-    });
-
-    const User = mongoose.model('User', userSchema);
-
-    const doc = new User({ name: 'Val', picture: '/123.png' });
-    doc.picture; // 'https://s3.amazonaws.com/mybucket/123.png'
-    doc.toObject({ getters: false }).picture; // '/123.png'
-    ```
-
-    Generally, you only use getters on primitive paths as opposed to arrays
-    or subdocuments. Because getters override what accessing a Mongoose path returns,
-    declaring a getter on an object may remove Mongoose change tracking for
-    that path.
-
-    ```javascript
-    const schema = new Schema({
-      arr: [{ url: String }]
-    });
-
-    const root = 'https://s3.amazonaws.com/mybucket';
-
-    // Bad, don't do this!
-    schema.path('arr').get(v => {
-      return v.map(el => Object.assign(el, { url: root + el.url }));
-    });
-
-    // Later
-    doc.arr.push({ key: String });
-    doc.arr[0]; // 'undefined' because every `doc.arr` creates a new array!
-    ```
-
-    Instead of declaring a getter on the array as shown above, you should
-    declare a getter on the `url` string as shown below. If you need to declare
-    a getter on a nested document or array, be very careful!
-
-    ```javascript
-    const schema = new Schema({
-      arr: [{ url: String }]
-    });
-
-    const root = 'https://s3.amazonaws.com/mybucket';
-
-    // Good, do this instead of declaring a getter on `arr`
-    schema.path('arr.0.url').get(v => `${root}${v}`);
-    ```
-
-    <h3 id="schemas"><a href="#schemas">Schemas</a></h3>
-
-    To declare a path as another [schema](./guide.html#definition),
-    set `type` to the sub-schema's instance.
-
-    To set a default value based on the sub-schema's shape, simply set a default value,
-    and the value will be cast based on the sub-schema's definition before being set
-    during document creation.
-
-    ```javascript
-    const subSchema = new mongoose.Schema({
-      // some schema definition here
-    });
-
-    const schema = new mongoose.Schema({
-      data: {
-        type: subSchema
-        default: {}
-      }
-    });
-    ```
-
-    <h3 id="customtypes"><a href="#customtypes">Creating Custom Types</a></h3>
-
-    Mongoose can also be extended with [custom SchemaTypes](customschematypes.html). Search the
-    [plugins](http://plugins.mongoosejs.io)
-    site for compatible types like
-    [mongoose-long](https://github.com/aheckmann/mongoose-long),
-    [mongoose-int32](https://github.com/vkarpov15/mongoose-int32),
-    and
-    [other](https://github.com/aheckmann/mongoose-function)
-    [types](https://github.com/OpenifyIt/mongoose-types).
-
-    Read more about creating [custom SchemaTypes here](customschematypes.html).
-
-    <h3 id="path"><a href="#path">The `schema.path()` Function</a></h3>
-
-    The `schema.path()` function returns the instantiated schema type for a
-    given path.
-
-    ```javascript
-    const sampleSchema = new Schema({ name: { type: String, required: true } });
-    console.log(sampleSchema.path('name'));
-    // Output looks like:
-    /**
-     * SchemaString {
-     *   enumValues: [],
-     *   regExp: null,
-     *   path: 'name',
-     *   instance: 'String',
-     *   validators: ...
-     */
-     ```
-
-    You can use this function to inspect the schema type for a given path,
-    including what validators it has and what the type is.
-
-    <h3 id="further-reading"><a href="#further-reading">Further Reading</a></h3>
-
-    <ul>
-      <li><a href="https://masteringjs.io/tutorials/mongoose/schematype">An Introduction to Mongoose SchemaTypes</a></li>
-      <li><a href="https://kb.objectrocket.com/mongo-db/mongoose-schema-types-1418">Mongoose Schema Types</a></li>
-    </ul>
diff --git a/docs/source/acquit.js b/docs/source/acquit.js
index 126fdb71336..bd85ba6f43e 100644
--- a/docs/source/acquit.js
+++ b/docs/source/acquit.js
@@ -7,11 +7,6 @@ var marked = require('marked');
 require('acquit-ignore')();
 
 var files = [
-  {
-    input: 'test/docs/defaults.test.js',
-    output: 'defaults.html',
-    title: 'Defaults'
-  },
   {
     input: 'test/docs/discriminators.test.js',
     output: 'discriminators.html',
diff --git a/docs/source/index.js b/docs/source/index.js
index 29437b6eb44..a78a24b1767 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -2,13 +2,14 @@
 'use strict';
 exports['index.pug'] = require('./home');
 exports['docs/api.pug'] = require('./api');
-exports['docs/browser.md'] = { guide: true, title: 'Browser Library', acquit: true, markdown: true };
-exports['docs/index.pug'] = { title: 'Getting Started' };
-exports['docs/production.pug'] = require('./production');
 exports['docs/prior.pug'] = require('./prior');
-exports['docs/guides.pug'] = { guide: true, schema: true, title: 'Schemas' };
-exports['docs/guide.pug'] = { guide: true, schema: true, title: 'Schemas', acquit: true };
-exports['docs/schematypes.pug'] = { guide: true, schema: true, title: 'SchemaTypes' };
+
+exports['docs/defaults.md'] = { title: 'Defaults', acquit: true, markdown: true };
+exports['docs/index.md'] = { title: 'Getting Started', markdown: true };
+exports['docs/browser.md'] = { guide: true, title: 'Browser Library', acquit: true, markdown: true };
+exports['docs/guides.md'] = { guide: true, schema: true, title: 'Schemas', markdown: true };
+exports['docs/guide.md'] = { guide: true, schema: true, title: 'Schemas', acquit: true, markdown: true };
+exports['docs/schematypes.md'] = { guide: true, schema: true, title: 'SchemaTypes', markdown: true };
 exports['docs/middleware.md'] = { guide: true, title: 'Middleware', acquit: true, markdown: true };
 exports['docs/plugins.md'] = { guide: true, title: 'Plugins', markdown: true };
 exports['docs/subdocs.md'] = { guide: true, docs: true, title: 'SubDocuments', markdown: true };
diff --git a/docs/source/production.js b/docs/source/production.js
deleted file mode 100644
index 9a9cb59beb3..00000000000
--- a/docs/source/production.js
+++ /dev/null
@@ -1,5 +0,0 @@
-'use strict';
-module.exports = {
-    images: []
-  , title: 'Production'
-}
diff --git a/website.js b/website.js
index 067873360f1..f3c9562ee5d 100644
--- a/website.js
+++ b/website.js
@@ -33,7 +33,8 @@ const tests = [
   ...acquit.parse(fs.readFileSync('./test/es-next/findoneandupdate.test.es6.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/docs/custom-casting.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/es-next/getters-setters.test.es6.js').toString()),
-  ...acquit.parse(fs.readFileSync('./test/es-next/virtuals.test.es6.js').toString())
+  ...acquit.parse(fs.readFileSync('./test/es-next/virtuals.test.es6.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/docs/defaults.test.js').toString())
 ];
 
 function getVersion() {

From 3e0e897e2f0d191eee617e73ebcf716a39becc27 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 22 May 2021 16:43:45 -0400
Subject: [PATCH 2076/2348] refactor: use markdown rather than acquit and pug
 for docs

Fix #10271
---
 docs/advanced_schemas.md     |  13 +++
 docs/customschematypes.md    |  19 ++++
 docs/discriminators.md       |  42 ++++++++
 docs/promises.md             |  75 ++++++++++++++
 docs/source/acquit.js        |  94 -----------------
 docs/source/index.js         |   5 +
 docs/validation.md           | 195 +++++++++++++++++++++++++++++++++++
 test/docs/validation.test.js |  30 ------
 website.js                   |  16 ++-
 9 files changed, 355 insertions(+), 134 deletions(-)
 create mode 100644 docs/advanced_schemas.md
 create mode 100644 docs/customschematypes.md
 create mode 100644 docs/discriminators.md
 create mode 100644 docs/promises.md
 delete mode 100644 docs/source/acquit.js
 create mode 100644 docs/validation.md

diff --git a/docs/advanced_schemas.md b/docs/advanced_schemas.md
new file mode 100644
index 00000000000..c1f6207b131
--- /dev/null
+++ b/docs/advanced_schemas.md
@@ -0,0 +1,13 @@
+## Advanced Schemas
+
+### Creating from ES6 Classes Using `loadClass()`
+
+Mongoose allows creating schemas from [ES6 classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes).
+The `loadClass()` function lets you pull in methods,
+statics, and virtuals from an ES6 class. A class method maps to a schema
+method, a static method maps to a schema static, and getters/setters map
+to virtuals.
+
+```javascript
+[require:Creating from ES6 Classes Using `loadClass\(\)`]
+```
\ No newline at end of file
diff --git a/docs/customschematypes.md b/docs/customschematypes.md
new file mode 100644
index 00000000000..dbc71d3f9d2
--- /dev/null
+++ b/docs/customschematypes.md
@@ -0,0 +1,19 @@
+## Custom Schema Types
+
+### Creating a Basic Custom Schema Type
+
+_New in Mongoose 4.4.0:_ Mongoose supports custom types. Before you
+reach for a custom type, however, know that a custom type is overkill
+for most use cases. You can do most basic tasks with
+[custom getters/setters](http://mongoosejs.com/docs/2.7.x/docs/getters-setters.html),
+[virtuals](http://mongoosejs.com/docs/guide.html#virtuals), and
+[single embedded docs](http://mongoosejs.com/docs/subdocs.html#single-embedded).
+
+Let's take a look at an example of a basic schema type: a 1-byte integer.
+To create a new schema type, you need to inherit from `mongoose.SchemaType`
+and add the corresponding property to `mongoose.Schema.Types`. The one
+method you need to implement is the `cast()` method.
+
+```javascript
+[require:Creating a Basic Custom Schema Type]
+```
\ No newline at end of file
diff --git a/docs/discriminators.md b/docs/discriminators.md
new file mode 100644
index 00000000000..3033a5d1276
--- /dev/null
+++ b/docs/discriminators.md
@@ -0,0 +1,42 @@
+## Discriminators
+
+### The `model.discriminator()` function
+
+Discriminators are a schema inheritance mechanism. They enable
+you to have multiple models with overlapping schemas on top of the
+same underlying MongoDB collection.
+
+Suppose you wanted to track different types of events in a single
+collection. Every event will have a timestamp, but events that
+represent clicked links should have a URL. You can achieve this
+using the `model.discriminator()` function. This function takes
+3 parameters, a model name, a discriminator schema and an optional
+key (defaults to the model name). It returns a model whose schema
+is the union of the base schema and the discriminator schema.
+
+```javascript
+[require:The `model.discriminator()` function]
+```
+
+### Discriminators save to the Event model's collection
+
+Suppose you created another discriminator to track events where
+a new user registered. These `SignedUpEvent` instances will be
+stored in the same collection as generic events and `ClickedLinkEvent`
+instances.
+
+```javascript
+[require:Discriminators save to the Event model's collection]
+```
+
+### Discriminator keys
+
+The way mongoose tells the difference between the different
+discriminator models is by the 'discriminator key', which is
+`__t` by default. Mongoose adds a String path called `__t`
+to your schemas that it uses to track which discriminator
+this document is an instance of.
+
+```javascript
+[require:Discriminator keys]
+```
\ No newline at end of file
diff --git a/docs/promises.md b/docs/promises.md
new file mode 100644
index 00000000000..ed426cf5175
--- /dev/null
+++ b/docs/promises.md
@@ -0,0 +1,75 @@
+## Promises
+
+### Built-in Promises
+
+Mongoose async operations, like `.save()` and queries, return thenables.
+This means that you can do things like `MyModel.findOne({}).then()` and
+`await MyModel.findOne({}).exec()` if you're using
+[async/await](http://thecodebarbarian.com/80-20-guide-to-async-await-in-node.js.html).
+ 
+You can find the return type of specific operations [in the api docs](https://mongoosejs.com/docs/api.html)
+You can also read more about [promises in Mongoose](https://masteringjs.io/tutorials/mongoose/promise).
+
+```javascript
+[require:Built-in Promises]
+```
+
+### Queries are not promises
+
+[Mongoose queries](http://mongoosejs.com/docs/queries.html) are **not** promises. They have a `.then()`
+function for [co](https://www.npmjs.com/package/co) and async/await as
+a convenience. If you need
+a fully-fledged promise, use the `.exec()` function.
+
+```javascript
+[require:Queries are not promises]
+```
+
+### Queries are thenable
+
+Although queries are not promises, queries are [thenables](https://promisesaplus.com/#terminology).
+That means they have a `.then()` function, so you can use queries as promises with either
+promise chaining or [async await](https://asyncawait.net)
+
+```javascript
+[require:Queries are thenable]
+```
+
+### Should You Use `exec()` With `await`?
+
+There are two alternatives for using `await` with queries:
+
+- `await Band.findOne();`
+- `await Band.findOne().exec();`
+ 
+As far as functionality is concerned, these two are equivalent.
+However, we recommend using `.exec()` because that gives you
+better stack traces.
+
+```javascript
+[require:Should You Use `exec()` With `await`]
+```
+
+### Plugging in your own Promises Library
+
+If you're an advanced user, you may want to plug in your own promise
+library like [bluebird](https://www.npmjs.com/package/bluebird). Just set
+`mongoose.Promise` to your favorite
+ES6-style promise constructor and mongoose will use it.
+
+```javascript
+[require:Plugging in your own Promises Library]
+```
+
+<i>
+  Want to learn how to check whether your favorite npm modules work with
+  async/await without cobbling together contradictory answers from Google
+  and Stack Overflow? Chapter 4 of Mastering Async/Await explains the
+  basic principles for determining whether frameworks like React and
+  Mongoose support async/await.
+  <a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=promises">Get your copy!</a>
+</i>
+<br><br>
+<a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=promises" style="margin-left: 100px">
+  <img src="/docs/images/asyncawait.png" style="width: 650px" />
+</a>
\ No newline at end of file
diff --git a/docs/source/acquit.js b/docs/source/acquit.js
deleted file mode 100644
index bd85ba6f43e..00000000000
--- a/docs/source/acquit.js
+++ /dev/null
@@ -1,94 +0,0 @@
-'use strict';
-var fs = require('fs');
-var acquit = require('acquit');
-var hl = require('highlight.js');
-var marked = require('marked');
-
-require('acquit-ignore')();
-
-var files = [
-  {
-    input: 'test/docs/discriminators.test.js',
-    output: 'discriminators.html',
-    title: 'Discriminators'
-  },
-  {
-    input: 'test/es-next/promises.test.es6.js',
-    output: 'promises.html',
-    title: 'Promises',
-    suffix: `
-      <div>
-        <br>
-        <i>
-          Want to learn how to check whether your favorite npm modules work with
-          async/await without cobbling together contradictory answers from Google
-          and Stack Overflow? Chapter 4 of Mastering Async/Await explains the
-          basic principles for determining whether frameworks like React and
-          Mongoose support async/await.
-          <a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=promises">Get your copy!</a>
-        </i>
-        <br><br>
-        <a href="http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=promises" style="margin-left: 100px">
-          <img src="/docs/images/asyncawait.png" style="width: 650px" />
-        </a>
-      </div>
-    `
-  },
-  {
-    input: 'test/docs/schematypes.test.js',
-    output: 'customschematypes.html',
-    title: 'Custom Schema Types'
-  },
-  {
-    input: 'test/docs/validation.test.js',
-    output: 'validation.html',
-    title: 'Validation'
-  },
-  {
-    input: 'test/docs/schemas.test.js',
-    output: 'advanced_schemas.html',
-    title: 'Advanced Schemas'
-  }
-];
-
-files.forEach(function(file) {
-  var blocks = acquit.parse(fs.readFileSync(file.input).toString());
-
-  for (var i = 0; i < blocks.length; ++i) {
-    var block = blocks[i];
-    block.identifier = toHtmlIdentifier(acquit.trimEachLine(block.contents));
-    block.contents = marked(acquit.trimEachLine(block.contents));
-    if (block.comments && block.comments.length) {
-      var last = block.comments.length - 1;
-      block.comments[last] =
-        marked(acquit.trimEachLine(block.comments[last]));
-    }
-    if (block.code) {
-      b.code = hl.highlight('javascript', b.code).value;
-    }
-
-    for (var j = 0; j < block.blocks.length; ++j) {
-      var b = block.blocks[j];
-      b.identifier = toHtmlIdentifier(acquit.trimEachLine(b.contents));
-      b.contents = marked(acquit.trimEachLine(b.contents), []);
-      if (b.comments && b.comments.length) {
-        var last = b.comments.length - 1;
-        b.comments[last] = marked(acquit.trimEachLine(b.comments[last]));
-      }
-    }
-  }
-
-  exports[file.output] = {
-    input: file.input,
-    title: file.title,
-    acquitBlocks: blocks,
-    suffix: file.suffix,
-    destination: file.output,
-    guide: true
-  }
-});
-
-function toHtmlIdentifier(str) {
-  return str.toLowerCase().replace(/ /g, '-').replace(/\(/g, '').
-    replace(/\)/, '').replace(/`/g, '').replace(/\./g, '-').replace(/'/g, '');
-}
diff --git a/docs/source/index.js b/docs/source/index.js
index a78a24b1767..df4be188c73 100644
--- a/docs/source/index.js
+++ b/docs/source/index.js
@@ -4,6 +4,11 @@ exports['index.pug'] = require('./home');
 exports['docs/api.pug'] = require('./api');
 exports['docs/prior.pug'] = require('./prior');
 
+exports['docs/advanced_schemas.md'] = { title: 'Advanced Schemas', acquit: true, markdown: true };
+exports['docs/validation.md'] = { title: 'Validation', acquit: true, markdown: true };
+exports['docs/customschematypes.md'] = { title: 'Custom Schema Types', acquit: true, markdown: true };
+exports['docs/promises.md'] = { title: 'Promises', acquit: true, markdown: true };
+exports['docs/discriminators.md'] = { title: 'Discriminators', acquit: true, markdown: true };
 exports['docs/defaults.md'] = { title: 'Defaults', acquit: true, markdown: true };
 exports['docs/index.md'] = { title: 'Getting Started', markdown: true };
 exports['docs/browser.md'] = { guide: true, title: 'Browser Library', acquit: true, markdown: true };
diff --git a/docs/validation.md b/docs/validation.md
new file mode 100644
index 00000000000..56cc4071f20
--- /dev/null
+++ b/docs/validation.md
@@ -0,0 +1,195 @@
+## Validation
+
+Before we get into the specifics of validation syntax, please keep the following rules in mind:
+
+- Validation is defined in the [SchemaType](./schematypes.html)
+- Validation is [middleware](./middleware.html). Mongoose registers validation as a `pre('save')` hook on every schema by default.
+- You can disable automatic validation before save by setting the [validateBeforeSave](./guide.html#validateBeforeSave) option
+- You can manually run validation using `doc.validate(callback)` or `doc.validateSync()`
+- You can manually mark a field as invalid (causing validation to fail) by using [`doc.invalidate(...)`](./api.html#document_Document-invalidate)
+- Validators are not run on undefined values. The only exception is the [`required` validator](./api.html#schematype_SchemaType-required).
+- Validation is asynchronously recursive; when you call [Model#save](./api.html#model_Model-save), sub-document validation is executed as well. If an error occurs, your [Model#save](./api.html#model_Model-save) callback receives it
+- Validation is customizable
+
+```javascript
+[require:Validation$]
+```
+
+### Built-in Validators
+
+Mongoose has several built-in validators.
+
+- All [SchemaTypes](./schematypes.html) have the built-in [required](./api.html#schematype_SchemaType-required) validator. The required validator uses the [SchemaType's `checkRequired()` function](./api.html#schematype_SchemaType-checkRequired) to determine if the value satisfies the required validator.
+- [Numbers](./api.html#schema-number-js) have [`min` and `max`](./schematypes.html#number-validators) validators.
+- [Strings](./api.html#schema-string-js) have [`enum`, `match`, `minLength`, and `maxLength`](./schematypes.html#string-validators) validators.
+
+Each of the validator links above provide more information about how to enable them and customize their error messages.
+
+```javascript
+[require:Built-in Validators]
+```
+
+### Custom Error Messages
+
+You can configure the error message for individual validators in your schema. There are two equivalent
+ways to set the validator error message:
+
+- Array syntax: `min: [6, 'Must be at least 6, got {VALUE}']`
+- Object syntax: `enum: { values: ['Coffee', 'Tea'], message: '{VALUE} is not supported' }`
+
+Mongoose also supports rudimentary templating for error messages.
+Mongoose replaces `{VALUE}` with the value being validated.
+
+```javascript
+[require:Custom Error Messages]
+```
+
+### The `unique` Option is Not a Validator
+
+A common gotcha for beginners is that the `unique` option for schemas
+is *not* a validator. It's a convenient helper for building [MongoDB unique indexes](https://docs.mongodb.com/manual/core/index-unique/).
+See the [FAQ](/docs/faq.html) for more information.
+
+```javascript
+[require:The `unique` Option is Not a Validator]
+```
+
+### Custom Validators
+
+If the built-in validators aren't enough, you can define custom validators
+to suit your needs.
+
+Custom validation is declared by passing a validation function.
+You can find detailed instructions on how to do this in the
+[`SchemaType#validate()` API docs](./api.html#schematype_SchemaType-validate).
+
+```javascript
+[require:Custom Validators]
+```
+
+### Async Custom Validators
+
+Custom validators can also be asynchronous. If your validator function
+returns a promise (like an `async` function), mongoose will wait for that
+promise to settle. If the returned promise rejects, or fulfills with
+the value `false`, Mongoose will consider that a validation error.
+
+```javascript
+[require:Async Custom Validators]
+```
+
+### Validation Errors
+
+Errors returned after failed validation contain an `errors` object
+whose values are `ValidatorError` objects. Each
+[ValidatorError](./api.html#error-validation-js) has `kind`, `path`,
+`value`, and `message` properties.
+A ValidatorError also may have a `reason` property. If an error was
+thrown in the validator, this property will contain the error that was
+thrown.
+
+```javascript
+[require:Validation Errors]
+```
+
+### Cast Errors
+
+Before running validators, Mongoose attempts to coerce values to the
+correct type. This process is called _casting_ the document. If
+casting fails for a given path, the `error.errors` object will contain
+a `CastError` object.
+
+Casting runs before validation, and validation does not run if casting
+fails. That means your custom validators may assume `v` is `null`,
+`undefined`, or an instance of the type specified in your schema.
+
+```javascript
+[require:Cast Errors]
+```
+
+### Required Validators On Nested Objects
+
+Defining validators on nested objects in mongoose is tricky, because
+nested objects are not fully fledged paths.
+
+```javascript
+[require:Required Validators On Nested Objects]
+```
+
+### Update Validators
+
+In the above examples, you learned about document validation. Mongoose also
+supports validation for [`update()`](/docs/api.html#query_Query-update),
+[`updateOne()`](/docs/api.html#query_Query-updateOne),
+[`updateMany()`](/docs/api.html#query_Query-updateMany),
+and [`findOneAndUpdate()`](/docs/api.html#query_Query-findOneAndUpdate) operations.
+Update validators are off by default - you need to specify
+the `runValidators` option.
+
+To turn on update validators, set the `runValidators` option for
+`update()`, `updateOne()`, `updateMany()`, or `findOneAndUpdate()`.
+Be careful: update validators are off by default because they have several
+caveats.
+
+```javascript
+[require:Update Validators$]
+```
+
+### Update Validators and `this`
+
+There are a couple of key differences between update validators and
+document validators. In the color validation function above, `this` refers
+to the document being validated when using document validation.
+However, when running update validators, the document being updated
+may not be in the server's memory, so by default the value of `this` is
+not defined.
+
+```javascript
+[require:Update Validators and `this`]
+```
+
+### The `context` option
+
+The `context` option lets you set the value of `this` in update validators
+to the underlying query.
+
+```javascript
+[require:The `context` option]
+```
+
+### Update Validators Only Run On Updated Paths
+
+The other key difference is that update validators only run on the paths
+specified in the update. For instance, in the below example, because
+'name' is not specified in the update operation, update validation will
+succeed.
+
+When using update validators, `required` validators **only** fail when
+you try to explicitly `$unset` the key.
+
+```javascript
+[require:Update Validators Only Run On Updated Paths]
+```
+
+### Update Validators Only Run For Some Operations
+
+One final detail worth noting: update validators **only** run on the
+following update operators:
+
+- `$set`
+- `$unset`
+- `$push` (>= 4.8.0)
+- `$addToSet` (>= 4.8.0)
+- `$pull` (>= 4.12.0)
+- `$pullAll` (>= 4.12.0)
+
+For instance, the below update will succeed, regardless of the value of
+`number`, because update validators ignore `$inc`.
+
+Also, `$push`, `$addToSet`, `$pull`, and `$pullAll` validation does
+**not** run any validation on the array itself, only individual elements
+of the array.
+
+```javascript
+[require:Update Validators Only Run For Some Operations]
+```
\ No newline at end of file
diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index bfe421b5c83..4e56bcb0592 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -627,34 +627,4 @@ describe('validation docs', function() {
       });
     });
   });
-
-  /**
-   * New in 4.8.0: update validators also run on `$push` and `$addToSet`
-   */
-
-  it('On $push and $addToSet', function(done) {
-    const testSchema = new Schema({
-      numbers: [{ type: Number, max: 0 }],
-      docs: [{
-        name: { type: String, required: true }
-      }]
-    });
-
-    const Test = db.model('TestPush', testSchema);
-
-    const update = {
-      $push: {
-        numbers: 1,
-        docs: { name: null }
-      }
-    };
-    const opts = { runValidators: true };
-    Test.updateOne({}, update, opts, function(error) {
-      assert.ok(error.errors['numbers']);
-      assert.ok(error.errors['docs']);
-      // acquit:ignore:start
-      done();
-      // acquit:ignore:end
-    });
-  });
 });
diff --git a/website.js b/website.js
index f3c9562ee5d..568d60de4ca 100644
--- a/website.js
+++ b/website.js
@@ -34,7 +34,12 @@ const tests = [
   ...acquit.parse(fs.readFileSync('./test/docs/custom-casting.test.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/es-next/getters-setters.test.es6.js').toString()),
   ...acquit.parse(fs.readFileSync('./test/es-next/virtuals.test.es6.js').toString()),
-  ...acquit.parse(fs.readFileSync('./test/docs/defaults.test.js').toString())
+  ...acquit.parse(fs.readFileSync('./test/docs/defaults.test.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/docs/discriminators.test.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/es-next/promises.test.es6.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/docs/schematypes.test.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/docs/validation.test.js').toString()),
+  ...acquit.parse(fs.readFileSync('./test/docs/schemas.test.js').toString())
 ];
 
 function getVersion() {
@@ -162,12 +167,3 @@ files.forEach(function(file) {
     });
   }
 });
-
-const _acquit = require('./docs/source/acquit');
-const acquitFiles = Object.keys(_acquit);
-acquitFiles.forEach(function(file) {
-  const filename = __dirname + '/docs/acquit.pug';
-  _acquit[file].editLink = 'https://github.com/Automattic/mongoose/blob/master/' +
-    _acquit[file].input.replace(process.cwd(), '');
-  pugify(filename, _acquit[file], __dirname + '/docs/' + file);
-});

From 72a87d79efa0bc62e98c53cefead013b636b1c47 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 22 May 2021 17:08:00 -0400
Subject: [PATCH 2077/2348] perf(schema+populate): avoid extra if check and
 unnecessary isPopulated calculation

Re: #9588
---
 .../populate/getModelsMapForPopulate.js       |  2 +-
 lib/schema/array.js                           | 49 +++++++++++++++----
 2 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 74ba2a51b96..4123926f517 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -512,7 +512,7 @@ function convertTo_id(val, schema) {
       }
     }
     if (val.isMongooseArray && val.$schema()) {
-      return val.$schema().cast(val, val.$parent(), false, void 0, { _skipSetters: true });
+      return val.$schema()._castForPopulate(val, val.$parent());
     }
 
     return [].concat(val);
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 43b492a5ef1..c81ee39a48a 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -356,10 +356,7 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
 
     value = MongooseArray(value, options.path || this._arrayPath || this.path, doc, this);
 
-    const _skipSetters = options._skipSetters;
-
-    const isPopulated = doc != null && doc.$__ != null && doc.populated(this.path);
-    if (isPopulated && init) {
+    if (init && doc != null && doc.$__ != null && doc.populated(this.path)) {
       return value;
     }
 
@@ -384,11 +381,7 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
               opts.arrayPathIndex = i;
             }
           }
-          if (_skipSetters) {
-            value[i] = caster.cast(value[i], doc, init, void 0, opts);
-          } else {
-            value[i] = caster.applySetters(value[i], doc, init, void 0, opts);
-          }
+          value[i] = caster.applySetters(value[i], doc, init, void 0, opts);
         }
       } catch (e) {
         // rethrow
@@ -411,6 +404,44 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
   throw new CastError('Array', util.inspect(value), this.path, null, this);
 };
 
+/*!
+ * ignore
+ */
+
+SchemaArray.prototype._castForPopulate = function _castForPopulate(value, doc) {
+  // lazy load
+  MongooseArray || (MongooseArray = require('../types').Array);
+
+  if (Array.isArray(value)) {
+    let i;
+    const len = value.length;
+
+    const caster = this.caster;
+    if (caster && this.casterConstructor !== Mixed) {
+      try {
+        for (i = 0; i < len; i++) {
+          const opts = {};
+          // Perf: creating `arrayPath` is expensive for large arrays.
+          // We only need `arrayPath` if this is a nested array, so
+          // skip if possible.
+          if (caster.$isMongooseArray && caster._arrayParentPath != null) {
+            opts.arrayPathIndex = i;
+          }
+
+          value[i] = caster.cast(value[i], doc, false, void 0, opts);
+        }
+      } catch (e) {
+        // rethrow
+        throw new CastError('[' + e.kind + ']', util.inspect(value), this.path + '.' + i, e, this);
+      }
+    }
+
+    return value;
+  }
+
+  throw new CastError('Array', util.inspect(value), this.path, null, this);
+};
+
 /*!
  * Ignore
  */

From a69666d47f36b492952fcc96034abb3d8843dae6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 22 May 2021 21:39:26 -0400
Subject: [PATCH 2078/2348] perf(array): improve array constructor performance
 on small arrays to improve nested array perf

Re: #9588
---
 lib/types/array.js | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/lib/types/array.js b/lib/types/array.js
index 802a62887a1..3526a03aa0d 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -30,18 +30,37 @@ const _basePush = Array.prototype.push;
  */
 
 function MongooseArray(values, path, doc, schematype) {
-  const arr = new CoreMongooseArray();
-  arr[arrayAtomicsSymbol] = {};
+  let arr;
 
   if (Array.isArray(values)) {
     const len = values.length;
-    for (let i = 0; i < len; ++i) {
-      _basePush.call(arr, values[i]);
+
+    // Perf optimizations for small arrays: much faster to use `...` than `for` + `push`,
+    // but large arrays may cause stack overflows. And for arrays of length 0/1, just
+    // modifying the array is faster. Seems small, but adds up when you have a document
+    // with thousands of nested arrays.
+    if (len === 0) {
+      arr = new CoreMongooseArray();
+    } else if (len === 1) {
+      arr = new CoreMongooseArray(1);
+      arr[0] = values[0];
+    } else if (len < 10000) {
+      arr = new CoreMongooseArray(...values);
+    } else {
+      arr = new CoreMongooseArray();
+      for (let i = 0; i < len; ++i) {
+        _basePush.call(arr, values[i]);
+      }
     }
 
     if (values[arrayAtomicsSymbol] != null) {
       arr[arrayAtomicsSymbol] = values[arrayAtomicsSymbol];
+    } else {
+      arr[arrayAtomicsSymbol] = {};
     }
+  } else {
+    arr = new CoreMongooseArray();
+    arr[arrayAtomicsSymbol] = {};
   }
 
   arr[arrayPathSymbol] = path;

From 90f09dbe121923dad264a4af5f96efa39263393c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 24 May 2021 11:26:20 -0400
Subject: [PATCH 2079/2348] fix: make #9588 improvements compatible with node
 v4

---
 lib/types/array.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/types/array.js b/lib/types/array.js
index 3526a03aa0d..dddf10a1aa8 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -45,7 +45,8 @@ function MongooseArray(values, path, doc, schematype) {
       arr = new CoreMongooseArray(1);
       arr[0] = values[0];
     } else if (len < 10000) {
-      arr = new CoreMongooseArray(...values);
+      arr = new CoreMongooseArray();
+      _basePush.apply(arr, values);
     } else {
       arr = new CoreMongooseArray();
       for (let i = 0; i < len; ++i) {

From b6037fb6cce1b2fc98cd7fc9c0c4fd9566c92ca9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 24 May 2021 13:01:18 -0400
Subject: [PATCH 2080/2348] chore: release 5.12.11

---
 History.md   | 12 ++++++++++++
 package.json |  2 +-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9a65a763e00..20223c94d75 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,15 @@
+5.12.11 / 2021-05-24
+====================
+ * fix(populate): skip applying setters when casting arrays for populate() to avoid issues with arrays of immutable elements #10264
+ * perf(schematype): avoid cloning setters every time we run setters #9588
+ * perf(get): add benchmarks and extra cases to speed up get() #9588
+ * perf(array): improve array constructor performance on small arrays to improve nested array perf #9588
+ * fix(index.d.ts): allow using type: [String] with string[] when using SchemaDefinition with generic #10261
+ * fix(index.d.ts): support ReadonlyArray as well as regular array where possible in schema definitions #10260
+ * docs(connection): document noListener option to useDb #10278 [stuartpb](https://github.com/stuartpb)
+ * docs: migrate raw tutorial content from pug / JS to markdown #10271
+ * docs: fix typo #10269 [sanjib](https://github.com/sanjib)
+
 5.12.10 / 2021-05-18
 ====================
  * fix(query): allow setting `defaults` option on result documents from query options #7287 [IslandRhythms](https://github.com/IslandRhythms)
diff --git a/package.json b/package.json
index 8b8818193db..6297c7b2dfc 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.10",
+  "version": "5.12.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b52708656a34a649220529fca0240f3963cdfee6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 24 May 2021 13:13:40 -0400
Subject: [PATCH 2081/2348] docs: fix search build re: #10271

---
 docs/search.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/docs/search.js b/docs/search.js
index e22a460df39..d093bc812e2 100644
--- a/docs/search.js
+++ b/docs/search.js
@@ -47,6 +47,36 @@ for (const filename of files) {
         contents.push(content);
       }
     }
+  } else if (file.markdown) {
+    let text = fs.readFileSync(filename, 'utf8');
+    text = markdown(text);
+
+    const content = new Content({
+      title: file.title,
+      body: text,
+      url: filename.replace('.md', '.html').replace(/^docs/, '')
+    });
+
+    content.validateSync();
+
+    const $ = cheerio.load(text);
+
+    contents.push(content);
+
+    // Break up individual h3's into separate content for more fine grained search
+    $('h3').each((index, el) => {
+      el = $(el);
+      const title = el.text();
+      const html = el.nextUntil('h3').html();
+      const content = new Content({
+        title: `${file.title}: ${title}`,
+        body: html,
+        url: `${filename.replace('.md', '.html').replace(/^docs/, '')}#${el.prop('id')}`
+      });
+
+      content.validateSync();
+      contents.push(content);
+    });
   } else if (file.guide) {
     let text = fs.readFileSync(filename, 'utf8');
     text = text.substr(text.indexOf('block content') + 'block content\n'.length);

From cb72db9c7a5dfc0d9fcbdcc3c88ed5292a3da6c1 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 24 May 2021 17:17:01 -0400
Subject: [PATCH 2082/2348] added requested function

---
 lib/document.js | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 6618bd848a0..30d77882fe2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2460,7 +2460,10 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   if (typeof pathsToValidate === 'string') {
     pathsToValidate = pathsToValidate.split(' ');
   }
-  if (pathsToSkip) {
+  if (Array.isArray(pathsToValidate)) {
+    paths = _handlePathsToValidate(paths, pathsToValidate);
+  }
+  else if (pathsToSkip) {
     // make a new variable that is paths intersection !options.pathsToSkip
     const valPaths = new Set(paths);
     for (const path of pathsToSkip) {
@@ -2469,10 +2472,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
       }
     }
     // then send that to be validated
-    paths = _handlePathsToValidate(paths, valPaths);
-  }
-  if (Array.isArray(pathsToValidate)) {
-    paths = _handlePathsToValidate(paths, pathsToValidate);
+    paths = _handlePathsToSkip(paths, valPaths);
   }
   if (paths.length === 0) {
     return process.nextTick(function() {
@@ -2596,6 +2596,21 @@ function _handlePathsToValidate(paths, pathsToValidate) {
   return ret;
 }
 
+/*!
+ * ignore
+ */
+
+function _handlePathsToSkip(paths, valPaths) {
+  const _valPaths = new Set(valPaths);
+  const ret = [];
+  for (const path of paths) {
+    if (_valPaths.has(path)) {
+      ret.push(path);
+    }
+  }
+  return ret;
+}
+
 /**
  * Executes registered validation rules (skipping asynchronous validators) for this document.
  *

From abc36367f32939b264375500f82ac0b7c23cacfe Mon Sep 17 00:00:00 2001
From: Nathanael Demacon <nathanael.dmc@outlook.fr>
Date: Tue, 25 May 2021 11:06:15 +0200
Subject: [PATCH 2083/2348] `.map`'s `ResultType` must be an array if used over
 an array

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 8bb4022cfd8..269a7739d7b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2096,7 +2096,7 @@ declare module 'mongoose' {
      * Runs a function `fn` and treats the return value of `fn` as the new value
      * for the query to resolve to.
      */
-    map<MappedType>(fn: (doc: DocType) => MappedType): QueryWithHelpers<MappedType, DocType, THelpers>;
+    map<MappedType>(fn: (doc: DocType) => MappedType): QueryWithHelpers<ResultType extends unknown[] ? MappedType[] : MappedType, DocType, THelpers>;
 
     /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     maxDistance(val: number): this;

From 2bce69e86e846c66362c7f4977cf1da06ec558b9 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 26 May 2021 11:00:11 -0400
Subject: [PATCH 2084/2348] made requested changes

---
 lib/document.js | 23 +++++------------------
 1 file changed, 5 insertions(+), 18 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 30d77882fe2..8725d695f73 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2464,15 +2464,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }
   else if (pathsToSkip) {
-    // make a new variable that is paths intersection !options.pathsToSkip
-    const valPaths = new Set(paths);
-    for (const path of pathsToSkip) {
-      if (valPaths.has(path)) {
-        valPaths.delete(path);
-      }
-    }
-    // then send that to be validated
-    paths = _handlePathsToSkip(paths, valPaths);
+    paths = _handlePathsToSkip(paths, pathsToSkip);
   }
   if (paths.length === 0) {
     return process.nextTick(function() {
@@ -2600,15 +2592,10 @@ function _handlePathsToValidate(paths, pathsToValidate) {
  * ignore
  */
 
-function _handlePathsToSkip(paths, valPaths) {
-  const _valPaths = new Set(valPaths);
-  const ret = [];
-  for (const path of paths) {
-    if (_valPaths.has(path)) {
-      ret.push(path);
-    }
-  }
-  return ret;
+function _handlePathsToSkip(paths, pathsToSkip) {
+  pathsToSkip = new Set(pathsToSkip);
+  paths = paths.filter(p => !pathsToSkip.has(p));
+  return paths;
 }
 
 /**

From 80c5e0efecee6ba8b3f71369417431047b87a5da Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 26 May 2021 11:59:06 -0400
Subject: [PATCH 2085/2348] fixed deprecation warning for
 collection.findOneAndUpdate

---
 index.d.ts   |  6 +++++-
 lib/query.js | 17 ++++++++++-------
 package.json |  2 +-
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 269a7739d7b..a7024d5ef7b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -924,6 +924,10 @@ declare module 'mongoose' {
      * An alias for the `new` option. `returnOriginal: false` is equivalent to `new: true`.
      */
     returnOriginal?: boolean;
+    /**
+     * Another alias for the `new` option. `returnOriginal` is deprecated so this should be used.
+     */
+    returnDocument?: string;
     runValidators?: boolean;
     /** The session associated with this query. */
     session?: mongodb.ClientSession;
@@ -1883,7 +1887,7 @@ declare module 'mongoose' {
     }
   }
 
-  type ReturnsNewDoc = { new: true } | { returnOriginal: false };
+  type ReturnsNewDoc = { new: true } | { returnOriginal: false } | {returnDocument: 'after'};
 
   type QueryWithHelpers<ResultType, DocType extends Document, THelpers = {}> = Query<ResultType, DocType, THelpers> & THelpers;
 
diff --git a/lib/query.js b/lib/query.js
index da5be864214..8b83f30b817 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3109,7 +3109,7 @@ Query.prototype.findOneAndUpdate = function(criteria, doc, options, callback) {
 
 
   const returnOriginal = get(this, 'model.base.options.returnOriginal');
-  if (options.returnOriginal == null && returnOriginal != null) {
+  if (options.new == null && options.returnDocument == null && options.returnOriginal == null && returnOriginal != null) {
     options.returnOriginal = returnOriginal;
   }
 
@@ -3435,10 +3435,9 @@ Query.prototype.findOneAndReplace = function(filter, replacement, options, callb
   options = options || {};
 
   const returnOriginal = get(this, 'model.base.options.returnOriginal');
-  if (options.returnOriginal == null && returnOriginal != null) {
+  if (options.new == null && options.returnDocument == null && options.returnOriginal == null && returnOriginal != null) {
     options.returnOriginal = returnOriginal;
   }
-
   this.setOptions(options);
   this.setOptions({ overwrite: true });
 
@@ -3468,7 +3467,7 @@ Query.prototype._findOneAndReplace = wrapThunk(function(callback) {
 
   const filter = this._conditions;
   const options = this._optionsForExec();
-  convertNewToReturnOriginal(options);
+  convertNewToReturnDocument(options);
   let fields = null;
 
   let castedDoc = new this.model(this._update, null, true);
@@ -3510,11 +3509,15 @@ Query.prototype._findOneAndReplace = wrapThunk(function(callback) {
  * compat.
  */
 
-function convertNewToReturnOriginal(options) {
+function convertNewToReturnDocument(options) {
   if ('new' in options) {
-    options.returnOriginal = !options['new'];
+    options.returnDocument = options['new'] ? 'after' : 'before';
     delete options['new'];
   }
+  if ('returnOriginal' in options) {
+    options.returnDocument = options['returnOriginal'] ? 'before' : 'after';
+    delete options['returnOriginal'];
+  }
 }
 
 /*!
@@ -3669,7 +3672,7 @@ Query.prototype._findAndModify = function(type, callback) {
   if (useFindAndModify === false) {
     // Bypass mquery
     const collection = _this._collection.collection;
-    convertNewToReturnOriginal(opts);
+    convertNewToReturnDocument(opts);
 
     if (type === 'remove') {
       collection.findOneAndDelete(castedQuery, opts, _wrapThunkCallback(_this, function(error, res) {
diff --git a/package.json b/package.json
index 6297c7b2dfc..debc35fe651 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.8",
+    "mongodb": "^3.6.8",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.5",

From 2f9389941c9c063dde694dc66bf902070e863754 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 26 May 2021 12:03:30 -0400
Subject: [PATCH 2086/2348] made requested change

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index debc35fe651..6297c7b2dfc 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "^3.6.8",
+    "mongodb": "3.6.8",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.5",

From a05c2ef8a12028ed50b7a0ad3b5b42b9e3436048 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 May 2021 11:53:16 -0400
Subject: [PATCH 2087/2348] test(documentarray): repro #10272

---
 test/types.documentarray.test.js | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/test/types.documentarray.test.js b/test/types.documentarray.test.js
index 22de14b7323..1390f7e07eb 100644
--- a/test/types.documentarray.test.js
+++ b/test/types.documentarray.test.js
@@ -707,4 +707,28 @@ describe('types.documentarray', function() {
       then(() => Model.findById(doc)).
       then(doc => assert.deepEqual(doc.toObject().subDocArray, [{ name: 'foo' }]));
   });
+
+  it('keeps atomics after setting (gh-10272)', function() {
+    const MyChildSchema = new Schema({
+      name: String
+    });
+
+    const MyModelSchema = new Schema({
+      children: [MyChildSchema]
+    });
+
+    const Test = db.model('Test', MyModelSchema);
+
+    const doc = new Test();
+    doc.init({
+      children: [{ name: 'John' }, { name: 'Jane' }]
+    });
+
+    doc.children = [{ name: 'John' }];
+    doc.children = doc.children.concat([]);
+    doc.children.push({ name: 'Mary' });
+
+    assert.ok(doc.children.$atomics().$set);
+    assert.deepEqual(doc.children.$atomics().$set.map(v => v.name), ['John', 'Mary']);
+  });
 });

From 367e78268c360da113c06561ae72bcd269b360c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 27 May 2021 11:55:43 -0400
Subject: [PATCH 2088/2348] fix(documentarray): retain atomics when setting to
 a new array

Fix #10272
---
 lib/schema/documentarray.js | 5 +++++
 lib/schematype.js           | 1 -
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/schema/documentarray.js b/lib/schema/documentarray.js
index 29baf2303a9..509c7bf4595 100644
--- a/lib/schema/documentarray.js
+++ b/lib/schema/documentarray.js
@@ -18,6 +18,7 @@ const util = require('util');
 const utils = require('../utils');
 const getConstructor = require('../helpers/discriminator/getConstructor');
 
+const arrayAtomicsSymbol = require('../helpers/symbols').arrayAtomicsSymbol;
 const arrayPathSymbol = require('../helpers/symbols').arrayPathSymbol;
 const documentArrayParent = require('../helpers/symbols').documentArrayParent;
 
@@ -401,6 +402,10 @@ DocumentArrayPath.prototype.cast = function(value, doc, init, prev, options) {
     value = new MongooseDocumentArray(value, this.path, doc);
   }
 
+  if (prev != null) {
+    value[arrayAtomicsSymbol] = prev[arrayAtomicsSymbol] || {};
+  }
+
   if (options.arrayPathIndex != null) {
     value[arrayPathSymbol] = this.path + '.' + options.arrayPathIndex;
   }
diff --git a/lib/schematype.js b/lib/schematype.js
index 8c87fdb0349..03ea4b9377e 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -1097,7 +1097,6 @@ SchemaType.prototype._castNullish = function _castNullish(v) {
 
 SchemaType.prototype.applySetters = function(value, scope, init, priorVal, options) {
   let v = this._applySetters(value, scope, init, priorVal, options);
-
   if (v == null) {
     return this._castNullish(v);
   }

From 4046beec725ceb6295fa863fc56f4f3a13ba5a5b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 28 May 2021 10:35:48 -0400
Subject: [PATCH 2089/2348] chore: release 5.12.12

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 20223c94d75..c235fdaf724 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.12.12 / 2021-05-28
+====================
+ * fix(documentarray): retain atomics when setting to a new array #10272
+ * fix(query+model): fix deprecation warning for `returnOriginal` with `findOneAndUpdate()` #10298 #10297 #10292 #10285 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix(index.d.ts): make `map()` result an array if used over an array #10288 [quantumsheep](https://github.com/quantumsheep)
+
 5.12.11 / 2021-05-24
 ====================
  * fix(populate): skip applying setters when casting arrays for populate() to avoid issues with arrays of immutable elements #10264
diff --git a/package.json b/package.json
index 6297c7b2dfc..f6153b8c349 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.11",
+  "version": "5.12.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 1287f94156eab468fb2a4a3712ce3e954005b4ca Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 31 May 2021 18:53:02 +0200
Subject: [PATCH 2090/2348] refactor: use for of instead of using length and
 indexes

---
 lib/model.js | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 728db372e80..fa06b0a614d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -212,11 +212,8 @@ function _applyCustomWhere(doc, where) {
   if (doc.$where == null) {
     return;
   }
-
-  const keys = Object.keys(doc.$where);
-  const len = keys.length;
-  for (let i = 0; i < len; ++i) {
-    where[keys[i]] = doc.$where[keys[i]];
+  for (const key of Object.keys(doc.$where)) {
+    where[key] = doc.$where[key];
   }
 }
 

From e3502d58c29cfda14b62bfc905ee6bd0084addc7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 31 May 2021 18:55:42 +0200
Subject: [PATCH 2091/2348] refactor: use customWhere and apply versioning in
 bulkSave

---
 lib/model.js | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index fa06b0a614d..6174ca31915 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3608,7 +3608,14 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents) {
       throw validationError;
     }
 
-    const changes = document.getChanges();
+    const delta = document.$__delta();
+    const where = document.$__where(delta[0]);
+    const changes = delta[1];
+
+    _applyCustomWhere(document, where);
+
+    document.$__version(where, delta);
+
     if (document.isNew) {
       accumulator.push({
         insertOne: { document }
@@ -3616,7 +3623,7 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents) {
     } else if (!utils.isEmptyObject(changes)) {
       accumulator.push({
         updateOne: {
-          filter: { _id: document._id },
+          filter: where,
           update: changes
         }
       });

From fe80e1ec04a353ac4e94597af991e4c00f515e02 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 31 May 2021 19:06:57 +0200
Subject: [PATCH 2092/2348] feat(model): add optional skipValidation to
 buildBulkWriteOperations

---
 lib/model.js       | 35 ++++++++++++++++++++++++++---------
 test/model.test.js | 19 ++++++++++++++++++-
 2 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 6174ca31915..80ee6d6b4d5 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3531,7 +3531,7 @@ Model.bulkWrite = function(ops, options, callback) {
 Model.bulkSave = function(documents) {
   const preSavePromises = documents.map(buildPreSavePromise);
 
-  const writeOperations = this.buildBulkWriteOperations(documents);
+  const writeOperations = this.buildBulkWriteOperations(documents, { skipValidation: true });
 
   let bulkWriteResultPromise;
   return Promise.all(preSavePromises)
@@ -3592,20 +3592,29 @@ function handleSuccessfulWrite(document, resolve, reject) {
   });
 }
 
-
-Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents) {
+/**
+ *
+ * @param {[Document]} documents The array of documents to build write operations of
+ * @param {Object} options
+ * @param {Boolean} options.skipValidation defaults to `false`, when set to true, building the write operations will bypass validating the documents.
+ * @returns
+ */
+Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents, options) {
   if (!Array.isArray(documents)) {
     throw new Error(`bulkSave expects an array of documents to be passed, received \`${documents}\` instead`);
   }
 
+  setDefaultOptions();
 
   const writeOperations = documents.reduce((accumulator, document, i) => {
-    if (!(document instanceof Document)) {
-      throw new Error(`documents.${i} was not a mongoose document, documents must be an array of mongoose documents (instanceof mongoose.Document).`);
-    }
-    const validationError = document.validateSync();
-    if (validationError) {
-      throw validationError;
+    if (!options.skipValidation) {
+      if (!(document instanceof Document)) {
+        throw new Error(`documents.${i} was not a mongoose document, documents must be an array of mongoose documents (instanceof mongoose.Document).`);
+      }
+      const validationError = document.validateSync();
+      if (validationError) {
+        throw validationError;
+      }
     }
 
     const delta = document.$__delta();
@@ -3633,6 +3642,14 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents) {
   }, []);
 
   return writeOperations;
+
+
+  function setDefaultOptions() {
+    options = options || {};
+    if (options.skipValidation == null) {
+      options.skipValidation = false;
+    }
+  }
 };
 
 /**
diff --git a/test/model.test.js b/test/model.test.js
index 2325f573805..565dbe11df2 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7114,7 +7114,7 @@ describe('Model', function() {
     });
   });
 
-  describe('buildBulkWriteOperations', () => {
+  describe('buildBulkWriteOperations() (gh-9673)', () => {
     it('builds write operations', () => {
       return co(function*() {
 
@@ -7205,6 +7205,23 @@ describe('Model', function() {
         /documents\.1 was not a mongoose document/
       );
     });
+    it('skips validation when given `skipValidation` true', () => {
+      const userSchema = new Schema({
+        name: { type: String, minLength: 5 }
+      });
+
+      const User = db.model('User', userSchema);
+
+      const users = [
+        new User({ name: 'a' }),
+        new User({ name: 'Hafez2_gh-9673-1' }),
+        new User({ name: 'b' })
+      ];
+
+      const writeOperations = User.buildBulkWriteOperations(users, { skipValidation: true });
+
+      assert.equal(writeOperations.length, 3);
+    });
   });
 
   describe('bulkSave() (gh-9673)', function() {

From 297358e92fc6ece5f10482869e00f0a4c9ac83e2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 31 May 2021 19:12:52 +0200
Subject: [PATCH 2093/2348] revert package.json formatting

---
 package.json | 243 ++++++++++++++++++++++++++-------------------------
 1 file changed, 122 insertions(+), 121 deletions(-)

diff --git a/package.json b/package.json
index bab78328b32..f6153b8c349 100644
--- a/package.json
+++ b/package.json
@@ -107,7 +107,8 @@
     "extends": [
       "eslint:recommended"
     ],
-    "overrides": [{
+    "overrides": [
+      {
         "files": [
           "**/*.{ts,tsx}"
         ],
@@ -125,128 +126,128 @@
           "@typescript-eslint/explicit-module-boundary-types": "off"
         }
       }
-    }],
-  "plugins": [
-    "mocha-no-only"
-  ],
-  "parserOptions": {
-    "ecmaVersion": 2015
-  },
-  "env": {
-    "node": true,
-    "es6": true
-  },
-  "rules": {
-    "comma-style": "error",
-    "indent": [
-      "error",
-      2,
-      {
-        "SwitchCase": 1,
-        "VariableDeclarator": 2
-      }
     ],
-    "keyword-spacing": "error",
-    "no-whitespace-before-property": "error",
-    "no-buffer-constructor": "warn",
-    "no-console": "off",
-    "no-multi-spaces": "error",
-    "no-constant-condition": "off",
-    "func-call-spacing": "error",
-    "no-trailing-spaces": "error",
-    "no-undef": "error",
-    "no-unneeded-ternary": "error",
-    "no-const-assign": "error",
-    "no-useless-rename": "error",
-    "no-dupe-keys": "error",
-    "space-in-parens": [
-      "error",
-      "never"
+    "plugins": [
+      "mocha-no-only"
     ],
-    "spaced-comment": [
-      "error",
-      "always",
-      {
-        "block": {
-          "markers": [
-            "!"
-          ],
-          "balanced": true
+    "parserOptions": {
+      "ecmaVersion": 2015
+    },
+    "env": {
+      "node": true,
+      "es6": true
+    },
+    "rules": {
+      "comma-style": "error",
+      "indent": [
+        "error",
+        2,
+        {
+          "SwitchCase": 1,
+          "VariableDeclarator": 2
         }
-      }
-    ],
-    "key-spacing": [
-      "error",
-      {
-        "beforeColon": false,
-        "afterColon": true
-      }
-    ],
-    "comma-spacing": [
-      "error",
-      {
-        "before": false,
-        "after": true
-      }
-    ],
-    "array-bracket-spacing": 1,
-    "arrow-spacing": [
-      "error",
-      {
-        "before": true,
-        "after": true
-      }
-    ],
-    "object-curly-spacing": [
-      "error",
-      "always"
-    ],
-    "comma-dangle": [
-      "error",
-      "never"
-    ],
-    "no-unreachable": "error",
-    "quotes": [
-      "error",
-      "single"
-    ],
-    "quote-props": [
-      "error",
-      "as-needed"
-    ],
-    "semi": "error",
-    "no-extra-semi": "error",
-    "semi-spacing": "error",
-    "no-spaced-func": "error",
-    "no-throw-literal": "error",
-    "space-before-blocks": "error",
-    "space-before-function-paren": [
-      "error",
-      "never"
-    ],
-    "space-infix-ops": "error",
-    "space-unary-ops": "error",
-    "no-var": "warn",
-    "prefer-const": "warn",
-    "strict": [
-      "error",
-      "global"
-    ],
-    "no-restricted-globals": [
-      "error",
-      {
-        "name": "context",
-        "message": "Don't use Mocha's global context"
-      }
-    ],
-    "no-prototype-builtins": "off",
-    "mocha-no-only/mocha-no-only": [
-      "error"
-    ]
+      ],
+      "keyword-spacing": "error",
+      "no-whitespace-before-property": "error",
+      "no-buffer-constructor": "warn",
+      "no-console": "off",
+      "no-multi-spaces": "error",
+      "no-constant-condition": "off",
+      "func-call-spacing": "error",
+      "no-trailing-spaces": "error",
+      "no-undef": "error",
+      "no-unneeded-ternary": "error",
+      "no-const-assign": "error",
+      "no-useless-rename": "error",
+      "no-dupe-keys": "error",
+      "space-in-parens": [
+        "error",
+        "never"
+      ],
+      "spaced-comment": [
+        "error",
+        "always",
+        {
+          "block": {
+            "markers": [
+              "!"
+            ],
+            "balanced": true
+          }
+        }
+      ],
+      "key-spacing": [
+        "error",
+        {
+          "beforeColon": false,
+          "afterColon": true
+        }
+      ],
+      "comma-spacing": [
+        "error",
+        {
+          "before": false,
+          "after": true
+        }
+      ],
+      "array-bracket-spacing": 1,
+      "arrow-spacing": [
+        "error",
+        {
+          "before": true,
+          "after": true
+        }
+      ],
+      "object-curly-spacing": [
+        "error",
+        "always"
+      ],
+      "comma-dangle": [
+        "error",
+        "never"
+      ],
+      "no-unreachable": "error",
+      "quotes": [
+        "error",
+        "single"
+      ],
+      "quote-props": [
+        "error",
+        "as-needed"
+      ],
+      "semi": "error",
+      "no-extra-semi": "error",
+      "semi-spacing": "error",
+      "no-spaced-func": "error",
+      "no-throw-literal": "error",
+      "space-before-blocks": "error",
+      "space-before-function-paren": [
+        "error",
+        "never"
+      ],
+      "space-infix-ops": "error",
+      "space-unary-ops": "error",
+      "no-var": "warn",
+      "prefer-const": "warn",
+      "strict": [
+        "error",
+        "global"
+      ],
+      "no-restricted-globals": [
+        "error",
+        {
+          "name": "context",
+          "message": "Don't use Mocha's global context"
+        }
+      ],
+      "no-prototype-builtins": "off",
+      "mocha-no-only/mocha-no-only": [
+        "error"
+      ]
+    }
+  },
+  "funding": {
+    "type": "opencollective",
+    "url": "https://opencollective.com/mongoose"
   }
-},
-"funding": {
-  "type": "opencollective",
-  "url": "https://opencollective.com/mongoose"
 }
-}
\ No newline at end of file

From f050fc26e107cf585b9f84cb4df856721ac7d3d8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Jun 2021 11:46:31 -0400
Subject: [PATCH 2094/2348] fix(index.d.ts): allow specifying object with
 `values` array for schematype `enum`

Fix #10286
---
 index.d.ts                | 2 +-
 test/typescript/schema.ts | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index a7024d5ef7b..bf9e863a346 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1512,7 +1512,7 @@ declare module 'mongoose' {
     set?: (value: T, schematype?: this) => any;
 
     /** array of allowed values for this path. Allowed for strings, numbers, and arrays of strings */
-    enum?: Array<string | number | null> | ReadonlyArray<string | number | null> | { [path: string]: string | number | null };
+    enum?: Array<string | number | null> | ReadonlyArray<string | number | null> | { values: Array<string | number | null> | ReadonlyArray<string | number | null>, message?: string } | { [path: string]: string | number | null };
 
     /** The default [subtype](http://bsonspec.org/spec.html) associated with this buffer when it is stored in MongoDB. Only allowed for buffer paths */
     subtype?: number
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index a57d229d543..85189aef8cf 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -19,6 +19,7 @@ interface Movie {
   rating?: number,
   genre?: string,
   actionIntensity?: number,
+  status?: string,
   actors?: Actor[]
 }
 
@@ -52,6 +53,13 @@ const movieSchema = new Schema<Document<Movie>, Model<Document<Movie>>, Movie>({
       'Action intensity required for action genre'
     ]
   },
+  status: {
+    type: String,
+    enum: {
+      values: ['Announced', 'Released'],
+      message: 'Invalid value for `status`'
+    }
+  },
   actors: {
     type: [actorSchema],
     default: undefined

From 02ad246e566bf7d80f214caec69d887a6d56b502 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Jun 2021 11:57:53 -0400
Subject: [PATCH 2095/2348] fix(index.d.ts): allow using `SaveOptions` in
 `pre('save')` middleware in TypeScript

Fix #10279
---
 index.d.ts                    | 2 ++
 test/typescript/middleware.ts | 7 ++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index bf9e863a346..b40ed54a34f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1093,6 +1093,7 @@ declare module 'mongoose' {
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
   type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
+  type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
   type ErrorHandlingMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, err: NativeError, res: ResType, next: (err?: CallbackError) => void) => void;
 
@@ -1189,6 +1190,7 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
 
     /** Defines a pre hook for the model. */
+    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: 'save', fn: PreSaveMiddlewareFunction<T>): this;
     pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PreMiddlewareFunction<T>): this;
     pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: PreMiddlewareFunction<T>): this;
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index e82ec14c54f..cc172467f51 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Model, Document, Types, Query, Aggregate } from 'mongoose';
+import { Schema, model, Model, Document, SaveOptions, Query, Aggregate } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String' } });
 
@@ -22,6 +22,11 @@ schema.pre(['save', 'validate'], { query: false, document: true }, async functio
   await Test.findOne({});
 });
 
+schema.pre('save', function(next, opts: SaveOptions) {
+  console.log(opts.session);
+  next();
+});
+
 interface ITest extends Document {
   name?: string;
 }

From 6e2cbc454b600da2293d04adc5c8c19fc313dac1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Jun 2021 13:48:18 -0400
Subject: [PATCH 2096/2348] perf(schema): pre-calculate mapPaths to avoid
 looping over every path for each path when initing doc

Re: #10275
---
 lib/schema.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index a68517afb49..a8fd62722d9 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -113,6 +113,7 @@ function Schema(obj, options) {
   this.plugins = [];
   // For internal debugging. Do not use this to try to save a schema in MDB.
   this.$id = ++id;
+  this.mapPaths = [];
 
   this.s = {
     hooks: new Kareem()
@@ -319,6 +320,7 @@ Schema.prototype.clone = function() {
   s.$globalPluginsApplied = this.$globalPluginsApplied;
   s.$isRootDiscriminator = this.$isRootDiscriminator;
   s.$implicitlyCreated = this.$implicitlyCreated;
+  s.mapPaths = [].concat(this.mapPaths);
 
   if (this.discriminatorMapping != null) {
     s.discriminatorMapping = Object.assign({}, this.discriminatorMapping);
@@ -694,6 +696,7 @@ Schema.prototype.path = function(path, obj) {
     }
     this.paths[mapPath] = this.interpretAsType(mapPath,
       _mapType, this.options);
+    this.mapPaths.push(this.paths[mapPath]);
     schemaType.$__schemaType = this.paths[mapPath];
   }
 
@@ -840,10 +843,11 @@ function _pathToPositionalSyntax(path) {
  */
 
 function getMapPath(schema, path) {
-  for (const _path of Object.keys(schema.paths)) {
-    if (!_path.includes('.$*')) {
-      continue;
-    }
+  if (schema.mapPaths.length === 0) {
+    return null;
+  }
+  for (const val of schema.mapPaths) {
+    const _path = val.path;
     const re = new RegExp('^' + _path.replace(/\.\$\*/g, '\\.[^.]+') + '$');
     if (re.test(path)) {
       return schema.paths[_path];

From f61ad6f29bf7dadd62bbf751c81e1a1e718c6748 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 1 Jun 2021 13:48:18 -0400
Subject: [PATCH 2097/2348] perf(schema): pre-calculate mapPaths to avoid
 looping over every path for each path when initing doc

Re: #10275
---
 lib/schema.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index a68517afb49..a8fd62722d9 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -113,6 +113,7 @@ function Schema(obj, options) {
   this.plugins = [];
   // For internal debugging. Do not use this to try to save a schema in MDB.
   this.$id = ++id;
+  this.mapPaths = [];
 
   this.s = {
     hooks: new Kareem()
@@ -319,6 +320,7 @@ Schema.prototype.clone = function() {
   s.$globalPluginsApplied = this.$globalPluginsApplied;
   s.$isRootDiscriminator = this.$isRootDiscriminator;
   s.$implicitlyCreated = this.$implicitlyCreated;
+  s.mapPaths = [].concat(this.mapPaths);
 
   if (this.discriminatorMapping != null) {
     s.discriminatorMapping = Object.assign({}, this.discriminatorMapping);
@@ -694,6 +696,7 @@ Schema.prototype.path = function(path, obj) {
     }
     this.paths[mapPath] = this.interpretAsType(mapPath,
       _mapType, this.options);
+    this.mapPaths.push(this.paths[mapPath]);
     schemaType.$__schemaType = this.paths[mapPath];
   }
 
@@ -840,10 +843,11 @@ function _pathToPositionalSyntax(path) {
  */
 
 function getMapPath(schema, path) {
-  for (const _path of Object.keys(schema.paths)) {
-    if (!_path.includes('.$*')) {
-      continue;
-    }
+  if (schema.mapPaths.length === 0) {
+    return null;
+  }
+  for (const val of schema.mapPaths) {
+    const _path = val.path;
     const re = new RegExp('^' + _path.replace(/\.\$\*/g, '\\.[^.]+') + '$');
     if (re.test(path)) {
       return schema.paths[_path];

From f13cf143388588d1cc0dedc936e2c3cb0327bc9b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 2 Jun 2021 11:00:22 -0400
Subject: [PATCH 2098/2348] fix(index.d.ts): allow using `type: new Schema({
 ... })` when declaring schemas using `Document &` syntax

Fix #10287
---
 index.d.ts                | 10 +++++-----
 test/typescript/schema.ts | 24 ++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b40ed54a34f..834aa618501 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1246,9 +1246,9 @@ declare module 'mongoose' {
     ? (SchemaDefinitionWithBuiltInClass<T> | SchemaTypeOptions<T>) :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
-    Schema<any> |
-    Schema<any>[] |
-    ReadonlyArray<Schema<any>> |
+    Schema<any, any> |
+    Schema<any, any>[] |
+    ReadonlyArray<Schema<any, any>> |
     SchemaTypeOptions<T extends undefined ? any : T>[] |
     ReadonlyArray<SchemaTypeOptions<T extends undefined ? any : T>> |
     Function[] |
@@ -1427,13 +1427,13 @@ declare module 'mongoose' {
   export class SchemaTypeOptions<T> {
     type?:
       T extends string | number | boolean | Function ? SchemaDefinitionWithBuiltInClass<T> :
-      T extends Schema ? T :
+      T extends Schema<any, any> ? T :
       T extends object[] ? (Schema<Document<Unpacked<T>>>[] | ReadonlyArray<Schema<Document<Unpacked<T>>>>) :
       T extends string[] ? (SchemaDefinitionWithBuiltInClass<string>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<string>>) :
       T extends number[] ? (SchemaDefinitionWithBuiltInClass<number>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<number>>) :
       T extends boolean[] ? (SchemaDefinitionWithBuiltInClass<boolean>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<boolean>>) :
       T extends Function[] ? (SchemaDefinitionWithBuiltInClass<Function>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<Function>>) :
-      T | typeof SchemaType | Schema;
+      T | typeof SchemaType | Schema<any, any>;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 85189aef8cf..9ee1cc733cf 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -123,3 +123,27 @@ function gh10261() {
     }
   };
 }
+
+function gh10287() {
+  interface SubSchema {
+    testProp: string;
+  }
+
+  const subSchema = new Schema<Document & SubSchema, Model<Document & SubSchema>, SubSchema>({
+    testProp: Schema.Types.String
+  });
+
+  interface MainSchema {
+    subProp: SubSchema
+  }
+
+  const mainSchema1 = new Schema<Document & MainSchema, Model<Document & MainSchema>, MainSchema>({
+    subProp: subSchema
+  });
+
+  const mainSchema2 = new Schema<Document & MainSchema, Model<Document & MainSchema>, MainSchema>({
+    subProp: {
+      type: subSchema
+    }
+  });
+}

From bfe4dcdaf4d2085548fdcae4fdb2dda36733436f Mon Sep 17 00:00:00 2001
From: Wang Jie <i@i8e.net>
Date: Thu, 3 Jun 2021 21:59:25 +0800
Subject: [PATCH 2099/2348] fix: make `returnDocument` work (close #10321)

---
 lib/query.js                        |  2 +-
 test/model.findOneAndUpdate.test.js | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/query.js b/lib/query.js
index 8b83f30b817..ed17941b1c9 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3591,7 +3591,7 @@ Query.prototype._findAndModify = function(type, callback) {
   if (type === 'remove') {
     opts.remove = true;
   } else {
-    if (!('new' in opts) && !('returnOriginal' in opts)) {
+    if (!('new' in opts) && !('returnOriginal' in opts) && !('returnDocument' in opts)) {
       opts.new = false;
     }
     if (!('upsert' in opts)) {
diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 66af0a97349..93e732bb168 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -2495,4 +2495,16 @@ describe('model: findOneAndUpdate:', function() {
       assert.equal(doc.jobCategory.value, 'from setter 2');
     });
   });
+
+  it('returnDocument should work (gh-10321)', function() {
+    const testSchema = Schema({ a: Number });
+    const Model = db.model('Test', testSchema);
+
+    const opts = { returnDocument: 'after' };
+    return co(function*() {
+      const tmp = yield Model.create({ a: 1 });
+      const doc = yield Model.findOneAndUpdate({ _id: tmp._id }, { a: 2 }, opts).lean();
+      assert.equal(doc.a, 2);
+    });
+  });
 });

From cf64dbbded26c3580c08fd50a674e38c1fb01a3f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 10:24:33 -0400
Subject: [PATCH 2100/2348] fix: store a reference to `nextTick()` and
 `setTimeout()` to protect against fake timers

Fix #10296
---
 lib/collection.js                             | 2 +-
 lib/connection.js                             | 2 +-
 lib/cursor/AggregationCursor.js               | 3 ++-
 lib/cursor/QueryCursor.js                     | 3 ++-
 lib/document.js                               | 5 +++--
 lib/drivers/node-mongodb-native/connection.js | 4 +++-
 lib/helpers/cursor/eachAsync.js               | 3 ++-
 lib/helpers/immediate.js                      | 4 +++-
 lib/helpers/printJestWarning.js               | 7 +++++++
 lib/helpers/promiseOrCallback.js              | 5 +++--
 lib/helpers/query/completeMany.js             | 5 +++--
 lib/helpers/timers.js                         | 5 +++++
 lib/model.js                                  | 8 ++++----
 lib/query.js                                  | 9 +++++----
 lib/utils.js                                  | 3 ++-
 15 files changed, 46 insertions(+), 22 deletions(-)
 create mode 100644 lib/helpers/timers.js

diff --git a/lib/collection.js b/lib/collection.js
index 043e8c8a21b..df16146094d 100644
--- a/lib/collection.js
+++ b/lib/collection.js
@@ -141,7 +141,7 @@ Collection.prototype.doQueue = function() {
   }
   this.queue = [];
   const _this = this;
-  process.nextTick(function() {
+  immediate(function() {
     _this.emitter.emit('queue');
   });
   return this;
diff --git a/lib/connection.js b/lib/connection.js
index b32881289d2..d1292a72bc8 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -853,7 +853,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
       }
 
       if (this.listeners('error').length > 0) {
-        process.nextTick(() => this.emit('error', err));
+        immediate(() => this.emit('error', err));
       }
       throw err;
     });
diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 5023b1c7f8f..6131bab5d85 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -8,6 +8,7 @@ const MongooseError = require('../error/mongooseError');
 const Readable = require('stream').Readable;
 const promiseOrCallback = require('../helpers/promiseOrCallback');
 const eachAsync = require('../helpers/cursor/eachAsync');
+const immediate = require('../helpers/immediate');
 const util = require('util');
 
 /**
@@ -342,7 +343,7 @@ function _next(ctx, cb) {
   }
 
   if (ctx._error) {
-    return process.nextTick(function() {
+    return immediate(function() {
       callback(ctx._error);
     });
   }
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index e1c5ca75a5d..9c016a2facb 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -8,6 +8,7 @@ const Readable = require('stream').Readable;
 const promiseOrCallback = require('../helpers/promiseOrCallback');
 const eachAsync = require('../helpers/cursor/eachAsync');
 const helpers = require('../queryhelpers');
+const immediate = require('../helpers/immediate');
 const util = require('util');
 
 /**
@@ -348,7 +349,7 @@ function _next(ctx, cb) {
   }
 
   if (ctx._error) {
-    return process.nextTick(function() {
+    return immediate(function() {
       callback(ctx._error);
     });
   }
diff --git a/lib/document.js b/lib/document.js
index 5d11879b455..3c466289668 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -25,6 +25,7 @@ const get = require('./helpers/get');
 const getEmbeddedDiscriminatorPath = require('./helpers/document/getEmbeddedDiscriminatorPath');
 const handleSpreadDoc = require('./helpers/document/handleSpreadDoc');
 const idGetter = require('./plugins/idGetter');
+const immediate = require('./helpers/immediate');
 const isDefiningProjection = require('./helpers/projection/isDefiningProjection');
 const isExclusive = require('./helpers/projection/isExclusive');
 const inspect = require('util').inspect;
@@ -2463,7 +2464,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }
   if (paths.length === 0) {
-    return process.nextTick(function() {
+    return immediate(function() {
       const error = _complete();
       if (error) {
         return _this.$__schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
@@ -2495,7 +2496,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
     validated[path] = true;
     total++;
 
-    process.nextTick(function() {
+    immediate(function() {
       const schemaType = _this.$__schema.path(path);
 
       if (!schemaType) {
diff --git a/lib/drivers/node-mongodb-native/connection.js b/lib/drivers/node-mongodb-native/connection.js
index d2c4fea8c9f..9eb9fe812ed 100644
--- a/lib/drivers/node-mongodb-native/connection.js
+++ b/lib/drivers/node-mongodb-native/connection.js
@@ -6,6 +6,8 @@
 
 const MongooseConnection = require('../../connection');
 const STATES = require('../../connectionstate');
+const immediate = require('../../helpers/immediate');
+const setTimeout = require('../../helpers/timers').setTimeout;
 
 /**
  * A [node-mongodb-native](https://github.com/mongodb/node-mongodb-native) connection implementation.
@@ -188,7 +190,7 @@ function listen(conn) {
 
 NativeConnection.prototype.doClose = function(force, fn) {
   if (this.client == null) {
-    process.nextTick(() => fn());
+    immediate(() => fn());
     return this;
   }
 
diff --git a/lib/helpers/cursor/eachAsync.js b/lib/helpers/cursor/eachAsync.js
index ab4a8a41d4d..2ef0346e0d4 100644
--- a/lib/helpers/cursor/eachAsync.js
+++ b/lib/helpers/cursor/eachAsync.js
@@ -4,6 +4,7 @@
  * Module dependencies.
  */
 
+const immediate = require('../immediate');
 const promiseOrCallback = require('../promiseOrCallback');
 
 /**
@@ -80,7 +81,7 @@ module.exports = function eachAsync(next, fn, options, callback) {
 
         // Kick off the subsequent `next()` before handling the result, but
         // make sure we know that we still have a result to handle re: #8422
-        process.nextTick(() => done());
+        immediate(() => done());
 
         if (batchSize != null) {
           documentsBatch.push(doc);
diff --git a/lib/helpers/immediate.js b/lib/helpers/immediate.js
index ddb70607a1f..0a1c26c32f6 100644
--- a/lib/helpers/immediate.js
+++ b/lib/helpers/immediate.js
@@ -7,6 +7,8 @@
 
 'use strict';
 
+const nextTick = process.nextTick.bind(process);
+
 module.exports = function immediate(cb) {
-  return process.nextTick(cb);
+  return nextTick(cb);
 };
diff --git a/lib/helpers/printJestWarning.js b/lib/helpers/printJestWarning.js
index eb3a8eb7b1d..9338d42a868 100644
--- a/lib/helpers/printJestWarning.js
+++ b/lib/helpers/printJestWarning.js
@@ -5,4 +5,11 @@ if (typeof jest !== 'undefined' && typeof window !== 'undefined') {
     'with Jest\'s default jsdom test environment. Please make sure you read ' +
     'Mongoose\'s docs on configuring Jest to test Node.js apps: ' +
     'http://mongoosejs.com/docs/jest.html');
+}
+
+if (typeof jest !== 'undefined' && process.nextTick.toString().indexOf('nextTick') === -1) {
+  console.warn('Mongoose: looks like you\'re trying to test a Mongoose app ' +
+    'with Jest\'s mock timers enabled. Please make sure you read ' +
+    'Mongoose\'s docs on configuring Jest to test Node.js apps: ' +
+    'http://mongoosejs.com/docs/jest.html');
 }
\ No newline at end of file
diff --git a/lib/helpers/promiseOrCallback.js b/lib/helpers/promiseOrCallback.js
index 11fff2258ad..69ba38530c0 100644
--- a/lib/helpers/promiseOrCallback.js
+++ b/lib/helpers/promiseOrCallback.js
@@ -1,8 +1,9 @@
 'use strict';
 
 const PromiseProvider = require('../promise_provider');
+const immediate = require('./immediate');
 
-const emittedSymbol = Symbol.for('mongoose:emitted');
+const emittedSymbol = Symbol('mongoose:emitted');
 
 module.exports = function promiseOrCallback(callback, fn, ee, Promise) {
   if (typeof callback === 'function') {
@@ -15,7 +16,7 @@ module.exports = function promiseOrCallback(callback, fn, ee, Promise) {
         try {
           callback(error);
         } catch (error) {
-          return process.nextTick(() => {
+          return immediate(() => {
             throw error;
           });
         }
diff --git a/lib/helpers/query/completeMany.js b/lib/helpers/query/completeMany.js
index aabe59632df..a70f0c4b405 100644
--- a/lib/helpers/query/completeMany.js
+++ b/lib/helpers/query/completeMany.js
@@ -1,6 +1,7 @@
 'use strict';
 
 const helpers = require('../../queryhelpers');
+const immediate = require('../immediate');
 
 module.exports = completeMany;
 
@@ -29,10 +30,10 @@ function completeMany(model, docs, fields, userProvidedFields, opts, callback) {
       error = error || _error;
     }
     if (error != null) {
-      --count || process.nextTick(() => callback(error));
+      --count || immediate(() => callback(error));
       return;
     }
-    --count || process.nextTick(() => callback(error, arr));
+    --count || immediate(() => callback(error, arr));
   }
 
   for (let i = 0; i < len; ++i) {
diff --git a/lib/helpers/timers.js b/lib/helpers/timers.js
new file mode 100644
index 00000000000..fb03c71944a
--- /dev/null
+++ b/lib/helpers/timers.js
@@ -0,0 +1,5 @@
+'use strict';
+
+console.log('AA', setTimeout);
+
+exports.setTimeout = setTimeout;
\ No newline at end of file
diff --git a/lib/model.js b/lib/model.js
index 89843e93ae5..32320a27d00 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -289,9 +289,9 @@ Model.prototype.$__handleSave = function(options, callback) {
       // wouldn't know what _id was generated by mongodb either
       // nor would the ObjectId generated by mongodb necessarily
       // match the schema definition.
-      setTimeout(function() {
+      immediate(function() {
         callback(new MongooseError('document must have an _id before saving'));
-      }, 0);
+      });
       return;
     }
 
@@ -3312,7 +3312,7 @@ Model.$__insertMany = function(arr, options, callback) {
         // we have to execute callback at the nextTick to be compatible
         // with parallelLimit, as `results` variable has TDZ issue if we
         // execute the callback synchronously
-        return process.nextTick(() => callback(null, doc));
+        return immediate(() => callback(null, doc));
       }
       doc.validate({ __noPromise: true }, function(error) {
         if (error) {
@@ -4863,7 +4863,7 @@ Model.$handleCallbackError = function(callback) {
 
   const _this = this;
   return function() {
-    process.nextTick(() => {
+    immediate(() => {
       try {
         callback.apply(null, arguments);
       } catch (error) {
diff --git a/lib/query.js b/lib/query.js
index 8b83f30b817..a025f57fd2d 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -22,6 +22,7 @@ const promiseOrCallback = require('./helpers/promiseOrCallback');
 const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const hasDollarKeys = require('./helpers/query/hasDollarKeys');
 const helpers = require('./queryhelpers');
+const immediate = require('./helpers/immediate');
 const isExclusive = require('./helpers/projection/isExclusive');
 const isInclusive = require('./helpers/projection/isInclusive');
 const mquery = require('mquery');
@@ -2959,7 +2960,7 @@ function completeOne(model, doc, res, options, fields, userProvidedFields, pop,
 
   function _init(err) {
     if (err) {
-      return process.nextTick(() => callback(err));
+      return immediate(() => callback(err));
     }
 
 
@@ -2970,10 +2971,10 @@ function completeOne(model, doc, res, options, fields, userProvidedFields, pop,
       } else {
         res.value = null;
       }
-      return process.nextTick(() => callback(null, res));
+      return immediate(() => callback(null, res));
     }
     casted.$session(options.session);
-    process.nextTick(() => callback(null, casted));
+    immediate(() => callback(null, casted));
   }
 }
 
@@ -3914,7 +3915,7 @@ Query.prototype.validate = function validate(castedDoc, options, isOverwriting,
         updateValidators(this, this.model.schema, castedDoc, options, cb);
       }
     } catch (err) {
-      process.nextTick(function() {
+      immediate(function() {
         cb(err);
       });
     }
diff --git a/lib/utils.js b/lib/utils.js
index fd381fc20c9..d6e2dc4e355 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -12,6 +12,7 @@ const Decimal = require('./types/decimal128');
 const ObjectId = require('./types/objectid');
 const PopulateOptions = require('./options/PopulateOptions');
 const clone = require('./helpers/clone');
+const immediate = require('./helpers/immediate');
 const isObject = require('./helpers/isObject');
 const isBsonType = require('./helpers/isBsonType');
 const getFunctionName = require('./helpers/getFunctionName');
@@ -440,7 +441,7 @@ exports.tick = function tick(callback) {
     } catch (err) {
       // only nextTick on err to get out of
       // the event loop and avoid state corruption.
-      process.nextTick(function() {
+      immediate(function() {
         throw err;
       });
     }

From 2e3ae5d02e3549c05b8c6e78972cd28e3136cccf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 10:24:46 -0400
Subject: [PATCH 2101/2348] docs(jest): add more details about testing with
 jest 26+

Re: #10296
---
 docs/jest.md | 50 ++++++++++++++++++++++++++------------------------
 1 file changed, 26 insertions(+), 24 deletions(-)

diff --git a/docs/jest.md b/docs/jest.md
index 55e317e3611..2926961339b 100644
--- a/docs/jest.md
+++ b/docs/jest.md
@@ -2,16 +2,13 @@
 
 Jest is a client-side JavaScript testing library developed by Facebook.
 Because Jest is designed primarily for testing React applications, using it to test Node.js server-side applications comes with a lot of caveats.
-We strongly advise against using Jest for testing any Node.js apps unless you are an expert developer with an intimate knowledge of Jest.
+We strongly recommend using a different testing framework, like [Mocha](https://mochajs.org/).
 
 If you choose to delve into dangerous waters and test Mongoose apps with Jest, here's what you need to know:
 
 <h2 id="recommended-testenvironment"><a href="#recommended-testenvironment">Recommended <code>testEnvironment</code></a></h2>
 
-Do **not** use Jest's default [`jsdom` test environment](https://jestjs.io/docs/en/configuration.html#testenvironment-string)
-when testing Mongoose apps, _unless_ you are explicitly testing an
-application that only uses
-[Mongoose's browser library](https://mongoosejs.com/docs/browser.html).
+If you are using Jest `<=26`, do **not** use Jest's default [`jsdom` test environment](https://jestjs.io/docs/en/configuration.html#testenvironment-string) when testing Mongoose apps, _unless_ you are explicitly testing an application that only uses [Mongoose's browser library](https://mongoosejs.com/docs/browser.html). In Jest `>=27`, ["node" is Jest's default `testEnvironment`](https://jestjs.io/ro/blog/2021/05/25/jest-27#flipping-defaults), so this is no longer an issue.
 
 The `jsdom` test environment attempts to create a browser-like test
 environment in Node.js, and it comes with numerous nasty surprises like a
@@ -31,24 +28,29 @@ module.exports = {
 
 <h2 id="timer-mocks"><a href="#timer-mocks">Timer Mocks</a></h2>
 
-Absolutely do **not** use [timer mocks](https://jestjs.io/docs/en/timer-mocks.html)
-when testing Mongoose apps. Fake timers stub out global functions like
-`setTimeout()` and `setInterval()`, which causes problems when an underlying
-library uses these functions. The MongoDB Node.js driver uses these functions
-for deferring work until the next tick of the event loop and for monitoring
-connections to the MongoDB server.
-    
-Mongoose devs have already refactored out code
-to [avoid using `setImmediate()`](https://github.com/Automattic/mongoose/issues/6074)
-to defer work to the next tick of the event loop, but we can't reasonably
-ensure that every library Mongoose depends on doesn't use `setImmediate()`.
-
-Mongoose uses `nextTick()`, which [Jest's underlying dependency explicitly doesn't stub by default](https://sinonjs.org/releases/latest/fake-timers/).
-But, `process.nextTick()` isn't the same as `setImmediate()` because of
-[microtasks vs macrotasks](https://abc.danch.me/microtasks-macrotasks-more-on-the-event-loop-881557d7af6f#2261),
-so underlying libraries like the [MongoDB driver](http://npmjs.com/package/mongodb) may use `setImmediate()`.
-
-To work around this, create your own wrapper around `setTimeout()` and
+Absolutely do **not** use [timer mocks](https://jestjs.io/docs/en/timer-mocks.html) when testing Mongoose apps.
+This is especially important if you're using Jest `>=25`, which stubs out `process.nextTick()`.
+
+Fake timers stub out global functions like `setTimeout()` and `setInterval()`, which causes problems when an underlying library uses these functions.
+Mongoose and the MongoDB Node.js driver uses these functions for deferring work until the next tick of the event loop and for monitoring connections to the MongoDB server.
+
+If you absolutely must use timer mocks, make sure you import Mongoose **before** calling `useFakeTimers()`:
+
+```javascript
+// Fine for basic cases, but may still cause issues:
+const mongoose = require('mongoose');
+
+jest.useFakeTimers();
+
+// Bad:
+jest.useFakeTimers();
+
+const mongoose = require('mongoose');
+```
+
+Mongoose devs have already refactored out code to [avoid using `setImmediate()`](https://github.com/Automattic/mongoose/issues/6074) to defer work to the next tick of the event loop, but we can't reasonably ensure that every library Mongoose depends on doesn't use `setImmediate()`.
+
+A better alternative is to create your own wrapper around `setTimeout()` and
 stub that instead using [sinon](http://npmjs.com/package/sinon).
 
 ```javascript
@@ -73,7 +75,7 @@ in your tests.
 
 ## Further Reading
 
-Want to learn more about testing Mongoose apps? The
+Want to learn how to test Mongoose apps correctly? The
 [RESTful Web Services with Node.js and Express](https://pluralsight.pxf.io/c/1321469/424552/7490?u=https%3A%2F%2Fapp.pluralsight.com%2Flibrary%2Fcourses%2Fnode-js-express-rest-web-services%2Ftable-of-contents)
 course on Pluralsight has a great section on testing Mongoose apps with [Mocha](http://npmjs.com/package/mocha).
 

From d183c9724a5b337d6456d7882ce7837306c36346 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 10:37:16 -0400
Subject: [PATCH 2102/2348] fix(schema): avoid schema error when using Jest 26
 fake timers

Fix #10296
---
 docs/jest.md  | 2 +-
 lib/schema.js | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/docs/jest.md b/docs/jest.md
index 2926961339b..36e07845d45 100644
--- a/docs/jest.md
+++ b/docs/jest.md
@@ -1,6 +1,6 @@
 # Testing Mongoose with [Jest](https://www.npmjs.com/package/jest)
 
-Jest is a client-side JavaScript testing library developed by Facebook.
+Jest is a JavaScript runtime developed by Facebook that is usually used for testing.
 Because Jest is designed primarily for testing React applications, using it to test Node.js server-side applications comes with a lot of caveats.
 We strongly recommend using a different testing framework, like [Mocha](https://mochajs.org/).
 
diff --git a/lib/schema.js b/lib/schema.js
index a8fd62722d9..9a464257edc 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -978,6 +978,11 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
         ? type
         : type.schemaName || utils.getFunctionName(type);
 
+      // For Jest 26+, see #10296
+      if (name === 'ClockDate') {
+        name = 'Date';
+      }
+
       if (!MongooseTypes.hasOwnProperty(name)) {
         throw new TypeError('Invalid schema configuration: ' +
           `\`${name}\` is not a valid type within the array \`${path}\`.` +
@@ -1008,6 +1013,10 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
   if (name === 'ObjectID') {
     name = 'ObjectId';
   }
+  // For Jest 26+, see #10296
+  if (name === 'ClockDate') {
+    name = 'Date';
+  }
 
   if (MongooseTypes[name] == null) {
     throw new TypeError(`Invalid schema configuration: \`${name}\` is not ` +

From 1badbeb247b44553a69751cb271707364419f440 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 12:19:03 -0400
Subject: [PATCH 2103/2348] perf(document): pre split schematype paths when
 compiling schema to avoid extra overhead of splitting when hydrating
 documents

Re: #10275
---
 lib/document.js       |  4 ++--
 lib/helpers/timers.js |  2 --
 lib/schematype.js     | 15 +++++++++++++++
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 3c466289668..9e4fb5b24cc 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -356,7 +356,7 @@ function $__applyDefaults(doc, fields, skipId, exclude, hasIncludedChildren, isB
     }
 
     const type = doc.$__schema.paths[p];
-    const path = p.indexOf('.') === -1 ? [p] : p.split('.');
+    const path = type.splitPath();
     const len = path.length;
     let included = false;
     let doc_ = doc._doc;
@@ -487,7 +487,7 @@ Document.prototype.$__buildDoc = function(obj, fields, skipId, exclude, hasInclu
       }
     }
 
-    const path = p.split('.');
+    const path = this.$__schema.paths[p].splitPath();
     const len = path.length;
     const last = len - 1;
     let curPath = '';
diff --git a/lib/helpers/timers.js b/lib/helpers/timers.js
index fb03c71944a..7bd09c7418c 100644
--- a/lib/helpers/timers.js
+++ b/lib/helpers/timers.js
@@ -1,5 +1,3 @@
 'use strict';
 
-console.log('AA', setTimeout);
-
 exports.setTimeout = setTimeout;
\ No newline at end of file
diff --git a/lib/schematype.js b/lib/schematype.js
index 03ea4b9377e..393029ca048 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -47,6 +47,8 @@ function SchemaType(path, options, instance) {
     [];
   this.setters = [];
 
+  this.splitPath();
+
   options = options || {};
   const defaultOptions = this.constructor.defaultOptions || {};
   const defaultOptionsKeys = Object.keys(defaultOptions);
@@ -126,6 +128,19 @@ function SchemaType(path, options, instance) {
 
 SchemaType.prototype.OptionsConstructor = SchemaTypeOptions;
 
+/*!
+ * ignore
+ */
+
+SchemaType.prototype.splitPath = function() {
+  if (this._presplitPath != null) {
+    return this._presplitPath;
+  }
+
+  this._presplitPath = this.path.indexOf('.') === -1 ? [this.path] : this.path.split('.');
+  return this._presplitPath;
+};
+
 /**
  * Get/set the function used to cast arbitrary values to this type.
  *

From 184f10ff34b74def0029377129a4854196239bc4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 13:31:27 -0400
Subject: [PATCH 2104/2348] perf(query): avoid setting non-null sessions to
 avoid overhead from $getAllSubdocs()

Re: #10275
---
 lib/helpers/query/completeMany.js | 5 ++++-
 lib/query.js                      | 8 ++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/helpers/query/completeMany.js b/lib/helpers/query/completeMany.js
index a70f0c4b405..cdc56b72a6e 100644
--- a/lib/helpers/query/completeMany.js
+++ b/lib/helpers/query/completeMany.js
@@ -43,6 +43,9 @@ function completeMany(model, docs, fields, userProvidedFields, opts, callback) {
     } catch (error) {
       init(error);
     }
-    arr[i].$session(opts.session);
+
+    if (opts.session != null) {
+      arr[i].$session(opts.session);
+    }
   }
 }
diff --git a/lib/query.js b/lib/query.js
index a025f57fd2d..b37701a1bbb 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -2966,14 +2966,18 @@ function completeOne(model, doc, res, options, fields, userProvidedFields, pop,
 
     if (options.rawResult) {
       if (doc && casted) {
-        casted.$session(options.session);
+        if (options.session != null) {
+          casted.$session(options.session);
+        }
         res.value = casted;
       } else {
         res.value = null;
       }
       return immediate(() => callback(null, res));
     }
-    casted.$session(options.session);
+    if (options.session != null) {
+      casted.$session(options.session);
+    }
     immediate(() => callback(null, casted));
   }
 }

From 601c06d36330836bae17b44ccd786421be82d59a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 18:19:39 -0400
Subject: [PATCH 2105/2348] fix: fix tests re: #10275

---
 lib/schematype.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/schematype.js b/lib/schematype.js
index 393029ca048..62a714f85c5 100644
--- a/lib/schematype.js
+++ b/lib/schematype.js
@@ -136,6 +136,9 @@ SchemaType.prototype.splitPath = function() {
   if (this._presplitPath != null) {
     return this._presplitPath;
   }
+  if (this.path == null) {
+    return undefined;
+  }
 
   this._presplitPath = this.path.indexOf('.') === -1 ? [this.path] : this.path.split('.');
   return this._presplitPath;

From 26c65c0f2f527a0809863be3e086b5f3c1670571 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 18:47:08 -0400
Subject: [PATCH 2106/2348] perf(document): avoid unnecessary split in `get()`

Re: #10275
---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 9e4fb5b24cc..8498465b12f 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1606,7 +1606,7 @@ Document.prototype.get = function(path, type, options) {
       schema = virtual;
     }
   }
-  const pieces = path.split('.');
+  const pieces = path.indexOf('.') === -1 ? [path] : path.split('.');
   let obj = this._doc;
 
   if (schema instanceof VirtualType) {

From 12111c521ab3817926db69ed37a78ae72769b9f1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 19:09:18 -0400
Subject: [PATCH 2107/2348] perf(document): avoid creating nested paths when
 running `$getAllSubdocs()`

Fix #10275
---
 lib/document.js | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 8498465b12f..f0b4bd1d976 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3123,9 +3123,13 @@ Document.prototype.$getAllSubdocs = function $getAllSubdocs() {
 
   function docReducer(doc, seed, path) {
     let val = doc;
+    let isNested = false;
     if (path) {
       if (doc instanceof Document && doc[documentSchemaSymbol].paths[path]) {
         val = doc._doc[path];
+      } else if (doc instanceof Document && doc[documentSchemaSymbol].nested[path]) {
+        val = doc._doc[path];
+        isNested = true;
       } else {
         val = doc[path];
       }
@@ -3153,18 +3157,18 @@ Document.prototype.$getAllSubdocs = function $getAllSubdocs() {
           seed.push(doc);
         }
       });
-    } else if (val instanceof Document && val.$__isNested) {
-      seed = Object.keys(val).reduce(function(seed, path) {
-        return docReducer(val, seed, path);
-      }, seed);
+    } else if (isNested && val != null) {
+      for (const path of Object.keys(val)) {
+        docReducer(val, seed, path);
+      }
     }
     return seed;
   }
 
-  const _this = this;
-  const subDocs = Object.keys(this._doc).reduce(function(seed, path) {
-    return docReducer(_this, seed, path);
-  }, []);
+  const subDocs = [];
+  for (const path of Object.keys(this._doc)) {
+    docReducer(this, subDocs, path);
+  }
 
   return subDocs;
 };

From 5c936e9173c3be9596f2cf48bff69bcb144f617e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 3 Jun 2021 19:40:41 -0400
Subject: [PATCH 2108/2348] fix(index.d.ts): drill down into nested arrays when
 creating LeanDocument type

Fix #10293
---
 index.d.ts | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 834aa618501..ab5fe8dc530 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2377,10 +2377,12 @@ declare module 'mongoose' {
     T extends TreatAsPrimitives ? T : // primitives
     LeanDocument<T>; // Documents and everything else
 
+  type LeanArray<T extends unknown[]> = T extends unknown[][] ? LeanArray<T[number]>[] : LeanType<T[number]>[];
+
   export type _LeanDocument<T> = {
     [K in keyof T]:
     0 extends (1 & T[K]) ? T[K] : // any
-    T[K] extends unknown[] ? LeanType<T[K][number]>[] : // Array
+    T[K] extends unknown[] ? LeanArray<T[K]> : // Array
     T[K] extends Document ? LeanDocument<T[K]> : // Subdocument
     T[K];
   };

From c14562b37daf22731c150dee49d34dfdf180790c Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 4 Jun 2021 13:55:14 -0400
Subject: [PATCH 2109/2348] fix

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index ab5fe8dc530..69b500671b8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2760,7 +2760,7 @@ declare module 'mongoose' {
     export class ValidationError extends Error {
       name: 'ValidationError';
 
-      errors: { [path: string]: ValidatorError | CastError };
+      errors: { [path: string]: ValidatorError | CastError | ValidationError};
     }
 
     export class ValidatorError extends Error {

From 8d741b9a4fe553f47238cb82cc05c20434afc4e7 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Fri, 4 Jun 2021 13:56:28 -0400
Subject: [PATCH 2110/2348] linter fix

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 69b500671b8..5157f727c78 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2760,7 +2760,7 @@ declare module 'mongoose' {
     export class ValidationError extends Error {
       name: 'ValidationError';
 
-      errors: { [path: string]: ValidatorError | CastError | ValidationError};
+      errors: { [path: string]: ValidatorError | CastError | ValidationError };
     }
 
     export class ValidatorError extends Error {

From 73f399e9a71ad2fb5c257d0956959e7e305dfdd5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 14:05:46 -0400
Subject: [PATCH 2111/2348] test(document): repro #10295

---
 test/document.test.js | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index debeab2d62d..fcbc0e6286b 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10256,4 +10256,43 @@ describe('document', function() {
       assert.equal(validatorCallCount, 0);
     });
   });
+
+  it('clears child document modified when setting map path underneath single nested (gh-10295)', function() {
+    const SecondMapSchema = new mongoose.Schema({
+      data: { type: Map, of: Number, default: {}, _id: false }
+    });
+
+    const FirstMapSchema = new mongoose.Schema({
+      data: { type: Map, of: SecondMapSchema, default: {}, _id: false }
+    });
+
+    const NestedSchema = new mongoose.Schema({
+      data: { type: Map, of: SecondMapSchema, default: {}, _id: false }
+    });
+
+    const TestSchema = new mongoose.Schema({
+      _id: Number,
+      firstMap: { type: Map, of: FirstMapSchema, default: {}, _id: false },
+      nested: { type: NestedSchema, default: {}, _id: false }
+    });
+
+    const Test = db.model('Test', TestSchema);
+
+    return co(function*() {
+      const doc = yield Test.create({ _id: Date.now() });
+
+      // It's Ok!
+      doc.nested.data.set('second', {});
+      assert.ok(doc.modifiedPaths().includes('nested.data.second'), doc.modifiedPaths());
+      yield doc.save();
+
+      // It's ERROR!
+      doc.nested.data.get('second').data.set('final', 3);
+      assert.ok(doc.modifiedPaths().includes('nested.data.second.data.final'), doc.modifiedPaths());
+      yield doc.save();
+
+      const fromDb = yield Test.findById(doc).lean();
+      assert.equal(fromDb.nested.data.second.data.final, 3);
+    });
+  });
 });

From 78aa2a30b25cc7ef17a479f74fed1bf8c58a9ec0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 14:06:23 -0400
Subject: [PATCH 2112/2348] fix(document): correctly reset subdocument when
 resetting a map subdocument underneath a single nested subdoc after save

Fix #10295
---
 lib/document.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index f0b4bd1d976..836481f00d8 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2926,7 +2926,13 @@ Document.prototype.$__reset = function reset() {
     }).
     forEach(function(doc) {
       doc.$__reset();
-      _this.$__.activePaths.init(doc.$basePath);
+      if (doc.$__parent === _this) {
+        _this.$__.activePaths.init(doc.$basePath);
+      } else {
+        // If map path underneath nested path, may end up with a case where
+        // map path is modified but parent still needs to be reset. See gh-10295
+        doc.$__parent.$__reset();
+      }
     });
 
   // clear atomics

From fd954e1778a9ebb4abac364879a6806bc84e0931 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 14:09:47 -0400
Subject: [PATCH 2113/2348] fix(document): make #10295 fix more durable

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 836481f00d8..3bc47638093 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2928,7 +2928,7 @@ Document.prototype.$__reset = function reset() {
       doc.$__reset();
       if (doc.$__parent === _this) {
         _this.$__.activePaths.init(doc.$basePath);
-      } else {
+      } else if (doc.$__parent != null) {
         // If map path underneath nested path, may end up with a case where
         // map path is modified but parent still needs to be reset. See gh-10295
         doc.$__parent.$__reset();

From 5ccea277c2b1ecec28feb6e1a29fe960da2367d6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 14:57:07 -0400
Subject: [PATCH 2114/2348] chore: release 5.12.13

---
 History.md            | 10 ++++++++++
 package.json          |  2 +-
 test/document.test.js |  4 ++--
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/History.md b/History.md
index c235fdaf724..2619977a8da 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.12.13 / 2021-06-04
+====================
+ * perf(document): avoid creating nested paths when running `$getAllSubdocs()` #10275
+ * fix: make returnDocument option work with `findOneAndUpdate()` #10232 #10231 [cnwangjie](https://github.com/cnwangjie)
+ * fix(document): correctly reset subdocument when resetting a map subdocument underneath a single nested subdoc after save #10295
+ * perf(query): avoid setting non-null sessions to avoid overhead from $getAllSubdocs() #10275
+ * perf(document): pre split schematype paths when compiling schema to avoid extra overhead of splitting when hydrating documents #10275
+ * perf(schema): pre-calculate mapPaths to avoid looping over every path for each path when initing doc #10275
+ * fix(index.d.ts): drill down into nested arrays when creating LeanDocument type #10293
+
 5.12.12 / 2021-05-28
 ====================
  * fix(documentarray): retain atomics when setting to a new array #10272
diff --git a/package.json b/package.json
index f6153b8c349..c0d05e21ca1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.12",
+  "version": "5.12.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",
diff --git a/test/document.test.js b/test/document.test.js
index fcbc0e6286b..062695d27a4 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10283,12 +10283,12 @@ describe('document', function() {
 
       // It's Ok!
       doc.nested.data.set('second', {});
-      assert.ok(doc.modifiedPaths().includes('nested.data.second'), doc.modifiedPaths());
+      assert.ok(doc.modifiedPaths().indexOf('nested.data.second') !== -1, doc.modifiedPaths());
       yield doc.save();
 
       // It's ERROR!
       doc.nested.data.get('second').data.set('final', 3);
-      assert.ok(doc.modifiedPaths().includes('nested.data.second.data.final'), doc.modifiedPaths());
+      assert.ok(doc.modifiedPaths().indexOf('nested.data.second.data.final') !== -1, doc.modifiedPaths());
       yield doc.save();
 
       const fromDb = yield Test.findById(doc).lean();

From ed74af6596ff64d3e10fa3b048b6a2464558ad59 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 16:30:57 -0400
Subject: [PATCH 2115/2348] feat(drivers): emit operation-start/operation-end
 events to allow inspecting when operations start and end

Re: #10313
---
 lib/drivers/node-mongodb-native/collection.js | 43 ++++++++++++++++---
 1 file changed, 38 insertions(+), 5 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index c8afd294c40..b2dfe2632ff 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -7,6 +7,7 @@
 const MongooseCollection = require('../../collection');
 const MongooseError = require('../../error/mongooseError');
 const Collection = require('mongodb').Collection;
+const ObjectId = require('./objectid');
 const get = require('../../helpers/get');
 const sliced = require('sliced');
 const stream = require('stream');
@@ -128,6 +129,7 @@ function iter(i) {
     const _this = this;
     const debug = get(_this, 'conn.base.options.debug');
     const lastArg = arguments[arguments.length - 1];
+    const opId = new ObjectId();
 
     // If user force closed, queueing will hang forever. See #5664
     if (this.conn.$wasForceClosed) {
@@ -141,12 +143,14 @@ function iter(i) {
       }
     }
 
+    let _args = args;
+    let callback = null;
     if (this._shouldBufferCommands() && this.buffer) {
       if (syncCollectionMethods[i]) {
         throw new Error('Collection method ' + i + ' is synchronous');
       }
 
-      this.conn.emit('buffer', { method: i, args: args });
+      this.conn.emit('buffer', { _id: opId, collectionName: _this.name, method: i, args: args });
 
       let callback;
       let _args;
@@ -192,6 +196,16 @@ function iter(i) {
       }
 
       return promise;
+    } else if (!syncCollectionMethods[i] && typeof lastArg === 'function') {
+      callback = function collectionOperationCallback(err, res) {
+        if (err != null) {
+          _this.conn.emit('operation-end', { _id: opId, collectionName: _this.name, method: i, error: err });
+        } else {
+          _this.conn.emit('operation-end', { _id: opId, collectionName: _this.name, method: i, result: res });
+        }
+        return lastArg.apply(this, arguments);
+      };
+      _args = args.slice(0, args.length - 1).concat([callback]);
     }
 
     if (debug) {
@@ -207,6 +221,8 @@ function iter(i) {
       }
     }
 
+    this.conn.emit('operation-start', { _id: opId, collectionName: this.name, method: i, args: _args });
+
     try {
       if (collection == null) {
         const message = 'Cannot call `' + this.name + '.' + i + '()` before initial connection ' +
@@ -214,13 +230,30 @@ function iter(i) {
           'you have `bufferCommands = false`.';
         throw new MongooseError(message);
       }
-      return collection[i].apply(collection, args);
+      const ret = collection[i].apply(collection, _args);
+      if (ret != null && typeof ret.then === 'function') {
+        return ret.then(
+          res => {
+            this.conn.emit('operation-end', { _id: opId, collectionName: this.name, method: i, result: res });
+            return res;
+          },
+          err => {
+            this.conn.emit('operation-end', { _id: opId, collectionName: this.name, method: i, error: err });
+            throw err;
+          }
+        );
+      }
+      return ret;
     } catch (error) {
       // Collection operation may throw because of max bson size, catch it here
       // See gh-3906
-      if (args.length > 0 &&
-          typeof args[args.length - 1] === 'function') {
-        args[args.length - 1](error);
+      if (typeof callback === 'function') {
+        callback(error);
+      } else {
+        this.conn.emit('operation-end', { _id: opId, collectionName: this.name, method: i, error: error });
+      }
+      if (typeof lastArg === 'function') {
+        lastArg(error);
       } else {
         throw error;
       }

From 60eec7db2dc3c1334079b569f01f1d6390b65c24 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 17:23:35 -0400
Subject: [PATCH 2116/2348] fix: emit model name with operations

---
 lib/drivers/node-mongodb-native/collection.js | 28 +++++++++++++------
 lib/model.js                                  |  3 +-
 2 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index b2dfe2632ff..95f8652df1a 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -22,9 +22,11 @@ const util = require('util');
  * @api private
  */
 
-function NativeCollection(name, options) {
+function NativeCollection(name, conn, options) {
   this.collection = null;
   this.Promise = options.Promise || Promise;
+  this.modelName = options.modelName;
+  delete options.modelName;
   this._closed = false;
   MongooseCollection.apply(this, arguments);
 }
@@ -150,7 +152,13 @@ function iter(i) {
         throw new Error('Collection method ' + i + ' is synchronous');
       }
 
-      this.conn.emit('buffer', { _id: opId, collectionName: _this.name, method: i, args: args });
+      this.conn.emit('buffer', {
+        _id: opId,
+        modelName: _this.modelName,
+        collectionName: _this.name,
+        method: i,
+        args: args
+      });
 
       let callback;
       let _args;
@@ -186,7 +194,9 @@ function iter(i) {
         if (removed) {
           const message = 'Operation `' + this.name + '.' + i + '()` buffering timed out after ' +
             bufferTimeoutMS + 'ms';
-          callback(new MongooseError(message));
+          const err = new MongooseError(message);
+          this.conn.emit('buffer-end', { _id: opId, modelName: _this.modelName, collectionName: _this.name, method: i, error: err });
+          callback(err);
         }
       }, bufferTimeoutMS);
 
@@ -199,9 +209,9 @@ function iter(i) {
     } else if (!syncCollectionMethods[i] && typeof lastArg === 'function') {
       callback = function collectionOperationCallback(err, res) {
         if (err != null) {
-          _this.conn.emit('operation-end', { _id: opId, collectionName: _this.name, method: i, error: err });
+          _this.conn.emit('operation-end', { _id: opId, modelName: _this.modelName, collectionName: _this.name, method: i, error: err });
         } else {
-          _this.conn.emit('operation-end', { _id: opId, collectionName: _this.name, method: i, result: res });
+          _this.conn.emit('operation-end', { _id: opId, modelName: _this.modelName, collectionName: _this.name, method: i, result: res });
         }
         return lastArg.apply(this, arguments);
       };
@@ -221,7 +231,7 @@ function iter(i) {
       }
     }
 
-    this.conn.emit('operation-start', { _id: opId, collectionName: this.name, method: i, args: _args });
+    this.conn.emit('operation-start', { _id: opId, modelName: _this.modelName, collectionName: this.name, method: i, params: _args });
 
     try {
       if (collection == null) {
@@ -234,11 +244,11 @@ function iter(i) {
       if (ret != null && typeof ret.then === 'function') {
         return ret.then(
           res => {
-            this.conn.emit('operation-end', { _id: opId, collectionName: this.name, method: i, result: res });
+            this.conn.emit('operation-end', { _id: opId, modelName: this.modelName, collectionName: this.name, method: i, result: res });
             return res;
           },
           err => {
-            this.conn.emit('operation-end', { _id: opId, collectionName: this.name, method: i, error: err });
+            this.conn.emit('operation-end', { _id: opId, modelName: this.modelName, collectionName: this.name, method: i, error: err });
             throw err;
           }
         );
@@ -250,7 +260,7 @@ function iter(i) {
       if (typeof callback === 'function') {
         callback(error);
       } else {
-        this.conn.emit('operation-end', { _id: opId, collectionName: this.name, method: i, error: error });
+        this.conn.emit('operation-end', { _id: opId, modelName: _this.modelName, collectionName: this.name, method: i, error: error });
       }
       if (typeof lastArg === 'function') {
         lastArg(error);
diff --git a/lib/model.js b/lib/model.js
index 32320a27d00..b19084bb0d1 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4744,7 +4744,8 @@ Model.compile = function compile(name, schema, collectionName, connection, base)
   const collectionOptions = {
     schemaUserProvidedOptions: _userProvidedOptions,
     capped: schema.options.capped,
-    Promise: model.base.Promise
+    Promise: model.base.Promise,
+    modelName: name
   };
   if (schema.options.autoCreate !== void 0) {
     collectionOptions.autoCreate = schema.options.autoCreate;

From 17f4f9ef4be5faf3c4b89602ce04a1eeb80cf6a3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 17:24:05 -0400
Subject: [PATCH 2117/2348] chore: update opencollective sponsors

---
 index.pug | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/index.pug b/index.pug
index 6cd9cb816b2..7a39be7cf4a 100644
--- a/index.pug
+++ b/index.pug
@@ -322,9 +322,6 @@ html(lang='en')
               <a rel="sponsored" href="https://goread.io/buy-instagram-likes">
                 <img class="sponsor" src="https://goread.io/assets/images/Goreadlogo.png" style="height: 100px" alt="Buy Instagram Likes">
               </a>
-              <a rel="sponsored" href="https://followerspromotion.com/buy-instagram-likes/">
-                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/followerspromo.png" style="height: 100px" alt="Buy Instagram Likes">
-              </a>
               <a rel="sponsored" href="https://nflthursday.com/">
                 <img class="sponsor" src="https://images.opencollective.com/nfl-thursday/ac3e3cc/logo/256.png" style="height: 100px">
               </a>

From 79988b75fc300592bc589cd141718cc24e4dd560 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 4 Jun 2021 17:54:21 -0400
Subject: [PATCH 2118/2348] fix: remove unnecessary async devDependency that's
 causing npm audit warnings

Fix #10281
---
 package.json       |  1 -
 test/query.test.js | 17 ++---------------
 2 files changed, 2 insertions(+), 16 deletions(-)

diff --git a/package.json b/package.json
index c0d05e21ca1..d3ddd459e33 100644
--- a/package.json
+++ b/package.json
@@ -40,7 +40,6 @@
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",
-    "async": "2.6.2",
     "babel-loader": "8.1.0",
     "benchmark": "2.1.4",
     "bluebird": "3.5.5",
diff --git a/test/query.test.js b/test/query.test.js
index f0ae8245318..3a428a61439 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -2404,28 +2404,15 @@ describe('Query', function() {
       });
 
       it('throw on sync exceptions in callbacks (gh-6178)', function(done) {
-        const async = require('async');
         const schema = new Schema({});
         const Test = db.model('Test', schema);
 
         process.once('uncaughtException', err => {
-          assert.equal(err.message, 'woops');
+          assert.equal(err.message, 'Oops!');
           done();
         });
 
-        async.waterfall([
-          function(cb) {
-            Test.create({}, cb);
-          },
-          function(res, cb) {
-            Test.find({}, function() { cb(); });
-          },
-          function() {
-            throw new Error('woops');
-          }
-        ], function() {
-          assert.ok(false);
-        });
+        Test.find({}, function() { throw new Error('Oops!'); });
       });
     });
 

From b345fb6e44b054f75e6afb2acf277e087789728f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 5 Jun 2021 18:24:58 -0400
Subject: [PATCH 2119/2348] test(schema): repro #10329

---
 test/schema.test.js | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 1e1a6f1c34d..61098ed645c 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2648,4 +2648,17 @@ describe('schema', function() {
 
     assert.ok(ElementSchema.path('possibleElements').schema.path('textMatchFeatures.dynamic').schema.nested['css']);
   });
+
+  it('propagates map `ref` down to individual map elements (gh-10329)', function() {
+    const TestSchema = new mongoose.Schema({
+      testprop: {
+        type: Map,
+        of: Number,
+        ref: 'OtherModel'
+      }
+    });
+
+    assert.equal(TestSchema.path('testprop.$*').instance, 'Number');
+    assert.equal(TestSchema.path('testprop.$*').options.ref, 'OtherModel');
+  });
 });

From 6c55cc7207f2d98e37450250846047442081f36f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 5 Jun 2021 18:25:09 -0400
Subject: [PATCH 2120/2348] fix(schema): propagate Map `ref` to map elements
 schema type

Fix #10329
---
 lib/schema.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index 9a464257edc..bd7dea3951a 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -694,6 +694,10 @@ Schema.prototype.path = function(path, obj) {
         !utils.hasUserDefinedProperty(obj.of, this.options.typeKey);
       _mapType = isInlineSchema ? new Schema(obj.of) : obj.of;
     }
+    if (utils.hasUserDefinedProperty(obj, 'ref')) {
+      _mapType = { type: _mapType, ref: obj.ref };
+    }
+
     this.paths[mapPath] = this.interpretAsType(mapPath,
       _mapType, this.options);
     this.mapPaths.push(this.paths[mapPath]);

From eb886615913a1c5f4b5cf0bc30959efd16d58c63 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 7 Jun 2021 15:00:28 -0400
Subject: [PATCH 2121/2348] Update document.ts

---
 test/typescript/document.ts | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index 0db7014ac54..d9c610ac1df 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -1,6 +1,6 @@
 import { Schema, model, Document } from 'mongoose';
 
-const schema: Schema = new Schema({ name: { type: 'String' } });
+const schema: Schema = new Schema({ name: { type: 'String', required: true }, address: new Schema({ city: { type: String, required: true } }) });
 
 interface ITestBase {
   name?: string;
@@ -15,4 +15,10 @@ void async function main() {
 
   const p: Promise<ITest> = doc.remove();
   await p;
+
+}();
+
+void async function run() {
+  const user = new Test({ name: {}, address: {} });
+  user.validateSync();
 }();
\ No newline at end of file

From 10edc8c4482c4f03955d4302ff09a8a4beaaf7d1 Mon Sep 17 00:00:00 2001
From: Mohammadreza Amini <mr.amini0076@gmail.com>
Date: Tue, 8 Jun 2021 09:17:39 +0430
Subject: [PATCH 2122/2348] Add Options Parameter Description to Model.exists

---
 lib/model.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/model.js b/lib/model.js
index 32320a27d00..c9310056e5f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1073,6 +1073,7 @@ Model.prototype.model = function model(name) {
  * - `findOne()`
  *
  * @param {Object} filter
+ * @param {Object} [options] optional see [`Query.prototype.setOptions()`](http://mongoosejs.com/docs/api.html#query_Query-setOptions)
  * @param {Function} [callback] callback
  * @return {Promise}
  */

From 0ef7592f1468a28de6b16afe2a492045d9169961 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 8 Jun 2021 15:59:07 -0400
Subject: [PATCH 2123/2348] Update document.ts

---
 test/typescript/document.ts | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index d9c610ac1df..6a6413fb7e3 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -20,5 +20,7 @@ void async function main() {
 
 void async function run() {
   const user = new Test({ name: {}, address: {} });
-  user.validateSync();
+  const error = user.validateSync();
+  // its set in the ts file but not showing up here
+  error.errors.address.errors;
 }();
\ No newline at end of file

From 8f3b81061c7923cb01458b6dfcb8d621833113d7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 8 Jun 2021 17:04:09 -0400
Subject: [PATCH 2124/2348] test: fix tests

---
 test/typescript/document.ts | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index 6a6413fb7e3..9f2d8f355f0 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document } from 'mongoose';
+import { Schema, model, Document, Error } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String', required: true }, address: new Schema({ city: { type: String, required: true } }) });
 
@@ -21,6 +21,7 @@ void async function main() {
 void async function run() {
   const user = new Test({ name: {}, address: {} });
   const error = user.validateSync();
-  // its set in the ts file but not showing up here
-  error.errors.address.errors;
+  if (error != null) {
+    const _error: Error.ValidationError = error.errors.address as Error.ValidationError;
+  }
 }();
\ No newline at end of file

From 4c5a57de12b22a38c533cea6954100b0fc3671af Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 12 Jun 2021 20:00:03 -0400
Subject: [PATCH 2125/2348] fix(index.d.ts): correct constructor type for
 `Document`

Fix #10328
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 5157f727c78..392406c083b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -368,7 +368,7 @@ declare module 'mongoose' {
   }
 
   class Document<T = any, TQueryHelpers = any> {
-    constructor(doc?: T | any);
+    constructor(doc?: any);
 
     /** This documents _id. */
     _id?: T;

From 12bb5f8b45a06510e69b4ff7a461e22b9993ded8 Mon Sep 17 00:00:00 2001
From: Thiago <tkkisaki@gmail.com>
Date: Sat, 12 Jun 2021 22:59:20 -0300
Subject: [PATCH 2126/2348] fix(index.d.ts): improve typings for virtuals

---
 index.d.ts                  | 68 ++++++++++++++++++++++++++++++++-----
 test/typescript/virtuals.ts | 67 ++++++++++++++++++++++++++++++++++++
 2 files changed, 126 insertions(+), 9 deletions(-)
 create mode 100644 test/typescript/virtuals.ts

diff --git a/index.d.ts b/index.d.ts
index 392406c083b..682e73ce4f2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1225,13 +1225,13 @@ declare module 'mongoose' {
     statics: { [name: string]: (this: M, ...args: any[]) => any };
 
     /** Creates a virtual type with the given name. */
-    virtual(name: string, options?: any): VirtualType;
+    virtual(name: string, options?: VirtualTypeOptions<DocType>): VirtualType<DocType>;
 
     /** Object of currently defined virtuals on this schema */
     virtuals: any;
 
     /** Returns the virtual type with the given `name`. */
-    virtualpath(name: string): VirtualType | null;
+    virtualpath(name: string): VirtualType<DocType> | null;
   }
 
   type SchemaDefinitionWithBuiltInClass<T extends number | string | boolean | Function> = T extends number
@@ -1618,18 +1618,68 @@ declare module 'mongoose' {
     validator: ValidateFn<T> | LegacyAsyncValidateFn<T> | AsyncValidateFn<T>;
   }
 
-  class VirtualType {
+  interface VirtualTypeOptions<D = Document> {
+    /** If `ref` is not nullish, this becomes a populated virtual. */
+    ref?: string | Function;
+
+    /**  The local field to populate on if this is a populated virtual. */
+    localField?: string | Function;
+
+    /** The foreign field to populate on if this is a populated virtual. */
+    foreignField?: string | Function;
+
+    /**
+     * By default, a populated virtual is an array. If you set `justOne`,
+     * the populated virtual will be a single doc or `null`.
+     */
+    justOne?: boolean;
+
+    /** If you set this to `true`, Mongoose will call any custom getters you defined on this virtual. */
+    getters?: boolean;
+
+    /**
+     * If you set this to `true`, `populate()` will set this virtual to the number of populated
+     * documents, as opposed to the documents themselves, using `Query#countDocuments()`.
+     */
+    count?: boolean;
+
+    /** Add an extra match condition to `populate()`. */
+    match?: FilterQuery<D> | ((doc: D) => FilterQuery<D>);
+
+    /** Add a default `limit` to the `populate()` query. */
+    limit?: number;
+
+    /** Add a default `skip` to the `populate()` query. */
+    skip?: number;
+
+    /**
+     * For legacy reasons, `limit` with `populate()` may give incorrect results because it only
+     * executes a single query for every document being populated. If you set `perDocumentLimit`,
+     * Mongoose will ensure correct `limit` per document by executing a separate query for each
+     * document to `populate()`. For example, `.find().populate({ path: 'test', perDocumentLimit: 2 })`
+     * will execute 2 additional queries if `.find()` returns 2 documents.
+     */
+    perDocumentLimit?: number;
+
+    /** Additional options like `limit` and `lean`. */
+    options?: QueryOptions;
+  }
+
+  class VirtualType<D = Document> {
+    /** VirtualType constructor */
+    constructor(options?: VirtualTypeOptions);
+
     /** Applies getters to `value`. */
-    applyGetters(value: any, doc: Document): any;
+    applyGetters(value: any, doc: D): any;
+
     /** Applies setters to `value`. */
-    applySetters(value: any, doc: Document): any;
+    applySetters(value: any, doc: D): any;
 
     /** Adds a custom getter to this virtual. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
-    get(fn: Function): this;
+    get(fn: (this: D, value: any, virtual: this, doc: D) => any): this;
+
     /** Adds a custom setter to this virtual. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
-    set(fn: Function): this;
+    set(fn: (this: D, value: any, virtual: this, doc: D) => any): this;
   }
 
   namespace Schema {
diff --git a/test/typescript/virtuals.ts b/test/typescript/virtuals.ts
new file mode 100644
index 00000000000..cfb8604e5e2
--- /dev/null
+++ b/test/typescript/virtuals.ts
@@ -0,0 +1,67 @@
+import { Document, Model, Schema, model } from 'mongoose';
+
+interface IPerson {
+  _id: number;
+  firstName: string;
+  lastName: string;
+
+  fullName: string;
+}
+
+interface IPet {
+  name: string;
+  ownerId: number;
+
+  owner: IPerson;
+}
+
+const personSchema = new Schema<IPerson & Document, Model<IPerson & Document>, IPerson>({
+  _id: { type: Number, required: true },
+  firstName: { type: String, required: true },
+  lastName: { type: String, required: true }
+});
+
+const petSchema = new Schema<IPet & Document, Model<IPet & Document>, IPet>({
+  name: { type: String, required: true },
+  ownerId: { type: Number, required: true }
+});
+
+// Virtual getters and setters
+personSchema.virtual('fullName')
+  .get(function(value, virtual, doc) {
+    return `${this.firstName} ${this.lastName}`;
+  })
+  .set(function(value, virtual, doc) {
+    const splittedName = value.split(' ');
+    this.firstName = splittedName[0];
+    this.lastName = splittedName[1];
+  });
+
+// Arrow functions should not be used for virtual getters/setters.
+// See https://mongoosejs.com/docs/faq.html#arrow-functions
+personSchema.virtual('wrongVirtual')
+  .get((value, virtual, doc) => {
+    return `${this.doesNotWork}!!`;
+  })
+  .set((value, virtual, doc) => {
+    this.value = 'is not document';
+  });
+
+// Populated virtuals
+petSchema.virtual('owner', {
+  ref: 'Person',
+  localField: 'ownerId',
+  foreignField: '_id',
+  justOne: true
+});
+
+const Person = model('Person', personSchema);
+const Pet = model('Pet', petSchema);
+
+(async() => {
+  const person = await Person.create({ _id: 1, firstName: 'John', lastName: 'Wick' });
+  await Pet.create({ name: 'Andy', ownerId: person._id });
+
+  const pet = await Pet.findOne().populate('owner');
+  console.log(pet.owner.fullName); // John Wick
+})();

From 584e630743120f2786a286bface826b6f5b93846 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 12:25:37 -0400
Subject: [PATCH 2127/2348] docs(typescript): add schemas guide

Fix #10308
---
 docs/layout.pug            |  2 +
 docs/typescript/schemas.md | 89 ++++++++++++++++++++++++++++++++++++++
 static.js                  |  4 +-
 3 files changed, 93 insertions(+), 2 deletions(-)
 create mode 100644 docs/typescript/schemas.md

diff --git a/docs/layout.pug b/docs/layout.pug
index 1f0eb00c6a3..84fb3b8a7c3 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -102,6 +102,8 @@ html(lang='en')
               li.pure-menu-item.sub-item
                 a.pure-menu-link(href="/docs/typescript.html", class=outputUrl === '/docs/typescript.html' ? 'selected' : '') TypeScript
               - if (outputUrl.startsWith('/docs/typescript'))
+                li.pure-menu-item.tertiary-item
+                  a.pure-menu-link(href="/docs/typescript/schemas.html", class=outputUrl === '/docs/typescript/schemas.html' ? 'selected' : '') Schemas
                 li.pure-menu-item.tertiary-item
                   a.pure-menu-link(href="/docs/typescript/statics.html", class=outputUrl === '/docs/typescript/statics.html' ? 'selected' : '') Statics
                 li.pure-menu-item.tertiary-item
diff --git a/docs/typescript/schemas.md b/docs/typescript/schemas.md
new file mode 100644
index 00000000000..87aeabf53b8
--- /dev/null
+++ b/docs/typescript/schemas.md
@@ -0,0 +1,89 @@
+# Schemas in TypeScript
+
+Mongoose [schemas](/docs/guide.html) are how you tell Mongoose what your documents look like.
+Mongoose schemas are separate from TypeScript interfaces, so you need to define both a _document interface_ and a _schema_.
+
+```typescript
+import { Schema } from 'mongoose';
+
+// Document interface
+interface User {
+  name: string;
+  email: string;
+  avatar?: string;
+}
+
+// Schema
+const schema = new Schema<User>({
+  name: { type: String, required: true },
+  email: { type: String, required: true },
+  avatar: String
+});
+```
+
+By default, Mongoose does **not** check if your document interface lines up with your schema.
+For example, the above code won't throw an error if `email` is optional in the document interface, but `required` in `schema`.
+
+## Defining Middleware
+
+The Mongoose `Schema` class in TypeScript has 3 generic parameters:
+
+```typescript
+class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  // ...
+}
+```
+
+The first generic param, `DocType`, represents the type that Mongoose uses as `this` for document middleware.
+For example:
+
+```typescript
+schema.pre('save', function(): void {
+  console.log(this.name); // TypeScript knows that `this` is a `User` by default
+});
+```
+
+## Checking Field Names
+
+The 3rd generic param, `SchemaDefinitionType`, checks to make sure that every path in your schema is defined in your document interface.
+For example, the below code will fail to compile because `emaill` is a path in the schema, but not in the `SchemaDefinitionType`.
+
+```typescript
+import { Schema, Model } from 'mongoose';
+
+interface User {
+  name: string;
+  email: string;
+  avatar?: string;
+}
+
+// Object literal may only specify known properties, but 'emaill' does not exist in type ...
+// Did you mean to write 'email'?
+const schema = new Schema<User, Model<User>, User>({
+  name: { type: String, required: true },
+  emaill: { type: String, required: true },
+  avatar: String
+});
+```
+
+However, Mongoose does **not ** check for paths that are in the document interface, but not in the schema.
+For example, the below code compiles.
+
+```typescript
+import { Schema, Model } from 'mongoose';
+
+interface User {
+  name: string;
+  email: string;
+  avatar?: string;
+  createdAt: number;
+}
+
+const schema = new Schema<User, Model<User>, User>({
+  name: { type: String, required: true },
+  email: { type: String, required: true },
+  avatar: String
+});
+```
+
+This is because Mongoose has numerous features that add paths to your schema, like [timestamps](https://masteringjs.io/tutorials/mongoose/timestamps), [plugins](/docs/plugins.html), etc. without you explicitly putting these paths in the `Schema()` constructor.
\ No newline at end of file
diff --git a/static.js b/static.js
index 78e5d71b601..8aab78191e8 100644
--- a/static.js
+++ b/static.js
@@ -20,6 +20,6 @@ require('http').createServer(function(req, res) {
     });
   });
   req.resume();
-}).listen(8088);
+}).listen(8089);
 
-console.error('now listening on http://localhost:8088');
+console.error('now listening on http://localhost:8089');

From c406f6eca88bb8298b8e99b1dd80dcb3134f97c5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 12:42:35 -0400
Subject: [PATCH 2128/2348] docs(index): add port to quick start connection
 string

---
 docs/index.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/index.md b/docs/index.md
index 2668ace614e..69fdf994253 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -28,7 +28,7 @@ connection to the `test` database on our locally running instance of MongoDB.
 ```javascript
 // getting-started.js
 const mongoose = require('mongoose');
-mongoose.connect('mongodb://localhost/test', {useNewUrlParser: true, useUnifiedTopology: true});
+mongoose.connect('mongodb://localhost:27017/test', {useNewUrlParser: true, useUnifiedTopology: true});
 ```
 
 We have a pending connection to the test database running on localhost.

From dced85845fb8fe22c28807bdbe37c29e8e61a9b9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 14:15:24 -0400
Subject: [PATCH 2129/2348] test(populate): repro #10335

---
 test/model.populate.test.js | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 0796c849897..19a86ce4030 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10484,4 +10484,34 @@ describe('model: populate:', function() {
       assert.equal(myCat.friends[0].name, 'Garfield');
     });
   });
+
+  it('populates nested path in schema using `Model.populate()` static (gh-10335)', function() {
+    const Books = db.model('Book', new Schema({
+      name: String,
+      author: { _id: Schema.Types.ObjectId, name: String }
+    }));
+    const Authors = db.model('Author', new Schema({ name: String }));
+
+    return co(function*() {
+      const anAuthor = new Authors({ name: 'Author1' });
+      yield anAuthor.save();
+
+      const aBook1 = new Books({ name: 'Book1', author: { _id: anAuthor.id } });
+      yield aBook1.save();
+
+      const books = (yield Books.find().lean()).map(aBook => {
+        aBook.author = aBook.author._id;
+        return aBook;
+      });
+
+      const populatedBooks = yield Books.populate(books, [{
+        path: 'author',
+        model: 'Author',
+        select: '_id name'
+      }]);
+
+      assert.equal(populatedBooks.length, 1);
+      assert.equal(populatedBooks[0].author.name, 'Author1');
+    });
+  });
 });

From 8a2b7ee749098a65eca6aa27d4bfa7c8ad812064 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 14:16:07 -0400
Subject: [PATCH 2130/2348] fix(populate): allow populating nested path in
 schema using `Model.populate()`

Fix #10335
---
 lib/helpers/populate/getModelsMapForPopulate.js | 2 +-
 lib/queryhelpers.js                             | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index 4123926f517..f98731bca53 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -53,7 +53,7 @@ module.exports = function getModelsMapForPopulate(model, docs, options) {
     }
     // Populating a nested path should always be a no-op re: #9073.
     // People shouldn't do this, but apparently they do.
-    if (modelSchema.nested[options.path]) {
+    if (options._localModel != null && options._localModel.schema.nested[options.path]) {
       continue;
     }
     const isUnderneathDocArray = schema && schema.$isUnderneathDocArray;
diff --git a/lib/queryhelpers.js b/lib/queryhelpers.js
index c371f6399ab..7fdebdb6303 100644
--- a/lib/queryhelpers.js
+++ b/lib/queryhelpers.js
@@ -31,6 +31,10 @@ exports.preparePopulationOptions = function preparePopulationOptions(query, opti
       forEach(makeLean(options.lean));
   }
 
+  pop.forEach(opts => {
+    opts._localModel = query.model;
+  });
+
   return pop;
 };
 
@@ -71,6 +75,9 @@ exports.preparePopulationOptionsMQ = function preparePopulationOptionsMQ(query,
   pop.forEach(p => {
     p._queryProjection = projection;
   });
+  pop.forEach(opts => {
+    opts._localModel = query.model;
+  });
 
   return pop;
 };

From 967da2b3dc14f9f51ff97cea0d291eabb3c67470 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 16:59:47 -0400
Subject: [PATCH 2131/2348] perf(array): delay creating atomics and a few other
 small optimizations to shave 25% off of nested array benchmark

Re: #9588
---
 lib/helpers/arrayDepth.js |  3 +++
 lib/schema/array.js       | 10 ++++++----
 lib/types/array.js        |  6 +-----
 lib/types/core_array.js   |  4 +++-
 4 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/lib/helpers/arrayDepth.js b/lib/helpers/arrayDepth.js
index 2c6f2e58629..e55de7ffbea 100644
--- a/lib/helpers/arrayDepth.js
+++ b/lib/helpers/arrayDepth.js
@@ -9,6 +9,9 @@ function arrayDepth(arr) {
   if (arr.length === 0) {
     return { min: 1, max: 1, containsNonArrayItem: false };
   }
+  if (arr.length === 1 && !Array.isArray(arr[0])) {
+    return { min: 1, max: 1, containsNonArrayItem: false };
+  }
 
   const res = arrayDepth(arr[0]);
 
diff --git a/lib/schema/array.js b/lib/schema/array.js
index c81ee39a48a..bdfea596483 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -282,14 +282,14 @@ SchemaArray.prototype.applyGetters = function(value, scope) {
 };
 
 SchemaArray.prototype._applySetters = function(value, scope, init, priorVal) {
-  if (this.casterConstructor instanceof SchemaArray &&
+  if (this.casterConstructor.$isMongooseArray &&
       SchemaArray.options.castNonArrays &&
       !this[isNestedArraySymbol]) {
     // Check nesting levels and wrap in array if necessary
     let depth = 0;
     let arr = this;
     while (arr != null &&
-      arr instanceof SchemaArray &&
+      arr.$isMongooseArray &&
       !arr.$isMongooseDocumentArray) {
       ++depth;
       arr = arr.casterConstructor;
@@ -361,20 +361,22 @@ SchemaArray.prototype.cast = function(value, doc, init, prev, options) {
     }
 
     const caster = this.caster;
+    const isMongooseArray = caster.$isMongooseArray;
+    const isArrayOfNumbers = caster.instance === 'Number';
     if (caster && this.casterConstructor !== Mixed) {
       try {
         for (i = 0; i < len; i++) {
           // Special case: number arrays disallow undefined.
           // Re: gh-840
           // See commit 1298fe92d2c790a90594bd08199e45a4a09162a6
-          if (caster.instance === 'Number' && value[i] === void 0) {
+          if (isArrayOfNumbers && value[i] === void 0) {
             throw new MongooseError('Mongoose number arrays disallow storing undefined');
           }
           const opts = {};
           // Perf: creating `arrayPath` is expensive for large arrays.
           // We only need `arrayPath` if this is a nested array, so
           // skip if possible.
-          if (caster.$isMongooseArray) {
+          if (isMongooseArray) {
             if (options.arrayPath != null) {
               opts.arrayPathIndex = i;
             } else if (caster._arrayParentPath != null) {
diff --git a/lib/types/array.js b/lib/types/array.js
index dddf10a1aa8..9df2fdad713 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -56,22 +56,18 @@ function MongooseArray(values, path, doc, schematype) {
 
     if (values[arrayAtomicsSymbol] != null) {
       arr[arrayAtomicsSymbol] = values[arrayAtomicsSymbol];
-    } else {
-      arr[arrayAtomicsSymbol] = {};
     }
   } else {
     arr = new CoreMongooseArray();
-    arr[arrayAtomicsSymbol] = {};
   }
 
   arr[arrayPathSymbol] = path;
-  arr[arraySchemaSymbol] = void 0;
 
   // Because doc comes from the context of another function, doc === global
   // can happen if there was a null somewhere up the chain (see #3020)
   // RB Jun 17, 2015 updated to check for presence of expected paths instead
   // to make more proof against unusual node environments
-  if (doc && doc instanceof Document) {
+  if (doc != null && doc.$__ != null) {
     arr[arrayParentSymbol] = doc;
     arr[arraySchemaSymbol] = schematype || doc.schema.path(path);
   }
diff --git a/lib/types/core_array.js b/lib/types/core_array.js
index cdad35c686c..2c15b0a9f8a 100644
--- a/lib/types/core_array.js
+++ b/lib/types/core_array.js
@@ -94,7 +94,7 @@ class CoreMongooseArray extends Array {
    */
 
   $atomics() {
-    return this[arrayAtomicsSymbol];
+    return this[arrayAtomicsSymbol] || {};
   }
 
   /*!
@@ -328,6 +328,8 @@ class CoreMongooseArray extends Array {
       return this;
     }
 
+    this[arrayAtomicsSymbol] || (this[arrayAtomicsSymbol] = {});
+
     const atomics = this[arrayAtomicsSymbol];
 
     // reset pop/shift after save

From 93cc500ede7aa28b784efd30387df81c4f227d66 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 17:05:14 -0400
Subject: [PATCH 2132/2348] style: fix lint re: #9588

---
 lib/types/array.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/types/array.js b/lib/types/array.js
index 9df2fdad713..420edeeea91 100644
--- a/lib/types/array.js
+++ b/lib/types/array.js
@@ -5,7 +5,6 @@
 'use strict';
 
 const CoreMongooseArray = require('./core_array');
-const Document = require('../document');
 
 const arrayAtomicsSymbol = require('../helpers/symbols').arrayAtomicsSymbol;
 const arrayParentSymbol = require('../helpers/symbols').arrayParentSymbol;

From f676487d9863c4b0b561ce1bdfe8775603d5b9cf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 14 Jun 2021 17:54:31 -0400
Subject: [PATCH 2133/2348] docs: add a few more modern examples of using
 lambda re: #10280

---
 docs/lambda.md | 80 +++++++++++++++++++++++++++++++++++---------------
 1 file changed, 57 insertions(+), 23 deletions(-)

diff --git a/docs/lambda.md b/docs/lambda.md
index c03c16fc743..61c060828f8 100644
--- a/docs/lambda.md
+++ b/docs/lambda.md
@@ -23,11 +23,15 @@ exports.handler = async function(event, context) {
   // potentially expensive process of connecting to MongoDB every time.
   if (conn == null) {
     conn = mongoose.createConnection(uri, {
+      useNewUrlParser: true,
+      useUnifiedTopology: true,
       // Buffering means mongoose will queue up operations if it gets
       // disconnected from MongoDB and send them when it reconnects.
       // With serverless, better to fail fast if not connected.
       bufferCommands: false, // Disable mongoose buffering
-      bufferMaxEntries: 0 // and MongoDB driver buffering
+      // and tell the MongoDB driver to not wait more than 5 seconds
+      // before erroring out if it isn't connected
+      serverSelectionTimeoutMS: 5000
     });
     
     // `await`ing connection after assigning to the `conn` variable
@@ -45,38 +49,68 @@ exports.handler = async function(event, context) {
 };
 ```
 
-To import this function into Lambda, go [the AWS Lambda console](https://console.aws.amazon.com/lambda)
-and click "Create Function".
+## Connection Helper
 
-<a href="https://i.imgur.com/FlAD0vT.png"><img src="https://i.imgur.com/FlAD0vT.png"></a>
+The above code works fine for a single Lambda function, but what if you want to reuse the same connection logic in multiple Lambda functions?
+You can export the below function.
 
-Create a function called "mongoose-test" with the below settings:
+```javascript
+'use strict';
 
-<a href="https://i.imgur.com/YOYJzeO.png"><img src="https://i.imgur.com/YOYJzeO.png"></a>
+const mongoose = require('mongoose');
 
-Copy the source code into a file called `lambda.js`. Then run `npm install mongoose co`.
-Finally, run `zip -r mongoose-test.zip node_modules/ lambda.js` to create a
-zip that you can upload to Lambda using the "Upload a Zip File" option under "Function code".
-Make sure you also change the "Handler" input to `lambda.handler` to match the `lambda.js` file's `handler` function.
+let conn = null;
 
-<a href="https://i.imgur.com/BXc9egq.png"><img src="https://i.imgur.com/BXc9egq.png"></a>
+const uri = 'YOUR CONNECTION STRING HERE';
 
-Next, click the "Save" button and then the "Test" button. The "Test" button will
-ask you to create a new test event, just create one because your inputs don't matter
-for this example. Then, hit "Test" again to actually run your function:
+exports.connect = async function() {
+  if (conn == null) {
+    conn = mongoose.createConnection(uri, {
+      useNewUrlParser: true,
+      useUnifiedTopology: true,
+      bufferCommands: false, // Disable mongoose buffering
+      serverSelectionTimeoutMS: 5000
+    });
+    
+    // `await`ing connection after assigning to the `conn` variable
+    // to avoid multiple function calls creating new connections
+    await conn;
+  }
 
-<a href="https://i.imgur.com/2UKtWYq.png"><img src="https://i.imgur.com/2UKtWYq.png"></a>
+  return conn;
+};
+```
 
-If your MongoDB database goes down in between function calls, you may
-see the below error message:
+## Using `mongoose.connect()`
 
-```
-cannot find account after reload: could not find config for <hostname>
-```
+You can also use `mongoose.connect()`, so you can use `mongoose.model()` to create models.
 
-Lambda's JavaScript framework recently added support for
-async/await as long as you're using Node 8.x, so make sure you're not
-using Node.js 6.x.
+```javascript
+'use strict';
+
+const mongoose = require('mongoose');
+
+let conn = null;
+
+const uri = 'YOUR CONNECTION STRING HERE';
+
+exports.connect = async function() {
+  if (conn == null) {
+    conn = mongoose.connect(uri, {
+      useNewUrlParser: true,
+      useUnifiedTopology: true,
+      bufferCommands: false, // Disable mongoose buffering
+      serverSelectionTimeoutMS: 5000
+    }).then(() => mongoose);
+    
+    // `await`ing connection after assigning to the `conn` variable
+    // to avoid multiple function calls creating new connections
+    await conn;
+  }
+
+  return conn;
+};
+```
 
 *Want to learn how to check whether your favorite JavaScript frameworks, like [Express](http://expressjs.com/) or [React](https://reactjs.org/), work with async/await? Spoiler alert: neither Express nor React support async/await. Chapter 4 of Mastering Async/Await explains the basic principles for determining whether a framework supports async/await. [Get your copy!](http://asyncawait.net/?utm_source=mongoosejs&utm_campaign=lambda)*
 

From 007b4f8a9bf5ddd0427d1ca88267bb44f1d40a72 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Mon, 14 Jun 2021 18:00:22 -0400
Subject: [PATCH 2134/2348] began adding feature

---
 lib/model.js               | 23 +++++++++++++++++++++++
 test/model.indexes.test.js | 11 +++++++++++
 2 files changed, 34 insertions(+)

diff --git a/lib/model.js b/lib/model.js
index c9310056e5f..03f2edc3592 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1411,6 +1411,29 @@ Model.syncIndexes = function syncIndexes(options, callback) {
   }, this.events);
 };
 
+Model.diffIndexes = function diffIndexes() {
+  const toDrop = [];
+  const toCreate = [];
+  // need this.listIndexes to get all
+  // the indexes in mongodb
+  // look at cleanIndexes()
+  // as it seems it is already done ↓
+  // use this.schema.indexes()
+  // to get indexes defined on the schema
+  this.listIndexes((err, indexes) => {
+    console.log('err', err);
+    console.log('indexes', indexes);
+    console.log(this.schema.indexes());
+
+    // Do const schemaIndexes = this.schema.indexes()[0];
+    // for (const key of schemaIndexes)
+    // log the keys first to make sure this is the correct line of thought
+    // use the isDefaultIdIndex() method to check for that
+  });
+
+  return { toDrop, toCreate };
+};
+
 /**
  * Deletes all indexes that aren't defined in this model's schema. Used by
  * `syncIndexes()`.
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index a0c339cdbae..63bd57a025c 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -683,5 +683,16 @@ describe('model', function() {
         yield User.collection.drop();
       });
     });
+    it('should do a dryRun gh-10316', function() {
+      return co(function*() {
+        const userSchema = new mongoose.Schema({ username: String }, { password: String }, { email: String });
+        userSchema.index({ password: 1 });
+        userSchema.index({ email: 1 });
+        const User = db.model('User', userSchema);
+        yield User.collection.createIndex({ age: 1 });
+        const result = User.diffIndexes();
+        assert.ok(result);
+      });
+    });
   });
 });

From 8cdadfa0f259ef059dfc6bc98f30a526f35e0b18 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 15 Jun 2021 15:13:56 +0200
Subject: [PATCH 2135/2348] test(model): repro #10346

---
 test/model.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index 0d5813675a2..d2cb3abb4cb 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -6754,6 +6754,22 @@ describe('Model', function() {
       assert.ifError(err);
     });
   });
+  it('Model.validate(...) uses object as context by default (gh-10346)', () => {
+    return co(function* () {
+      const userSchema = new mongoose.Schema({
+        name: { type: String, required: true },
+        age: { type: Number, required() {return this && this.name === 'John';} }
+      });
+
+      const User = db.model('User', userSchema);
+
+      const err1 = yield User.validate({ name: 'John' }).then(() => null, err => err);
+      assert.ok(err1);
+
+      const err2 = yield User.validate({ name: 'Sam' }).then(() => null, err => err);
+      assert.ok(err2 === null);
+    });
+  });
 
   it('sets correct `Document#op` with `save()` (gh-8439)', function() {
     const schema = Schema({ name: String });

From 9814070cd943505ec1f647b862da17293cc11d68 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 15 Jun 2021 15:14:26 +0200
Subject: [PATCH 2136/2348] fix(model): make validate use object under
 validation as default context if no context is provided

---
 lib/model.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index c9310056e5f..766807577d0 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4062,9 +4062,9 @@ Model.aggregate = function aggregate(pipeline, callback) {
  */
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
-  if (context === void 0 && obj instanceof Model) {
-    // For convenience, if we're validating a document, make `context` default to
-    // the model so users don't have to always pass `context`, re: gh-10132.
+  if (context === void 0) {
+    // For convenience, if we're validating a document or an object, make `context` default to
+    // the model so users don't have to always pass `context`, re: gh-10132, gh-10346
     context = obj;
   }
 

From e548f5410c8b32119ee1ac442385b4cab9c7e76c Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 15 Jun 2021 15:23:21 +0200
Subject: [PATCH 2137/2348] revert package.json formatting

---
 package.json | 243 ++++++++++++++++++++++++++-------------------------
 1 file changed, 122 insertions(+), 121 deletions(-)

diff --git a/package.json b/package.json
index b88319fbc49..539087ee264 100644
--- a/package.json
+++ b/package.json
@@ -106,7 +106,8 @@
     "extends": [
       "eslint:recommended"
     ],
-    "overrides": [{
+    "overrides": [
+      {
         "files": [
           "**/*.{ts,tsx}"
         ],
@@ -124,128 +125,128 @@
           "@typescript-eslint/explicit-module-boundary-types": "off"
         }
       }
-    }],
-  "plugins": [
-    "mocha-no-only"
-  ],
-  "parserOptions": {
-    "ecmaVersion": 2015
-  },
-  "env": {
-    "node": true,
-    "es6": true
-  },
-  "rules": {
-    "comma-style": "error",
-    "indent": [
-      "error",
-      2,
-      {
-        "SwitchCase": 1,
-        "VariableDeclarator": 2
-      }
     ],
-    "keyword-spacing": "error",
-    "no-whitespace-before-property": "error",
-    "no-buffer-constructor": "warn",
-    "no-console": "off",
-    "no-multi-spaces": "error",
-    "no-constant-condition": "off",
-    "func-call-spacing": "error",
-    "no-trailing-spaces": "error",
-    "no-undef": "error",
-    "no-unneeded-ternary": "error",
-    "no-const-assign": "error",
-    "no-useless-rename": "error",
-    "no-dupe-keys": "error",
-    "space-in-parens": [
-      "error",
-      "never"
+    "plugins": [
+      "mocha-no-only"
     ],
-    "spaced-comment": [
-      "error",
-      "always",
-      {
-        "block": {
-          "markers": [
-            "!"
-          ],
-          "balanced": true
+    "parserOptions": {
+      "ecmaVersion": 2015
+    },
+    "env": {
+      "node": true,
+      "es6": true
+    },
+    "rules": {
+      "comma-style": "error",
+      "indent": [
+        "error",
+        2,
+        {
+          "SwitchCase": 1,
+          "VariableDeclarator": 2
         }
-      }
-    ],
-    "key-spacing": [
-      "error",
-      {
-        "beforeColon": false,
-        "afterColon": true
-      }
-    ],
-    "comma-spacing": [
-      "error",
-      {
-        "before": false,
-        "after": true
-      }
-    ],
-    "array-bracket-spacing": 1,
-    "arrow-spacing": [
-      "error",
-      {
-        "before": true,
-        "after": true
-      }
-    ],
-    "object-curly-spacing": [
-      "error",
-      "always"
-    ],
-    "comma-dangle": [
-      "error",
-      "never"
-    ],
-    "no-unreachable": "error",
-    "quotes": [
-      "error",
-      "single"
-    ],
-    "quote-props": [
-      "error",
-      "as-needed"
-    ],
-    "semi": "error",
-    "no-extra-semi": "error",
-    "semi-spacing": "error",
-    "no-spaced-func": "error",
-    "no-throw-literal": "error",
-    "space-before-blocks": "error",
-    "space-before-function-paren": [
-      "error",
-      "never"
-    ],
-    "space-infix-ops": "error",
-    "space-unary-ops": "error",
-    "no-var": "warn",
-    "prefer-const": "warn",
-    "strict": [
-      "error",
-      "global"
-    ],
-    "no-restricted-globals": [
-      "error",
-      {
-        "name": "context",
-        "message": "Don't use Mocha's global context"
-      }
-    ],
-    "no-prototype-builtins": "off",
-    "mocha-no-only/mocha-no-only": [
-      "error"
-    ]
+      ],
+      "keyword-spacing": "error",
+      "no-whitespace-before-property": "error",
+      "no-buffer-constructor": "warn",
+      "no-console": "off",
+      "no-multi-spaces": "error",
+      "no-constant-condition": "off",
+      "func-call-spacing": "error",
+      "no-trailing-spaces": "error",
+      "no-undef": "error",
+      "no-unneeded-ternary": "error",
+      "no-const-assign": "error",
+      "no-useless-rename": "error",
+      "no-dupe-keys": "error",
+      "space-in-parens": [
+        "error",
+        "never"
+      ],
+      "spaced-comment": [
+        "error",
+        "always",
+        {
+          "block": {
+            "markers": [
+              "!"
+            ],
+            "balanced": true
+          }
+        }
+      ],
+      "key-spacing": [
+        "error",
+        {
+          "beforeColon": false,
+          "afterColon": true
+        }
+      ],
+      "comma-spacing": [
+        "error",
+        {
+          "before": false,
+          "after": true
+        }
+      ],
+      "array-bracket-spacing": 1,
+      "arrow-spacing": [
+        "error",
+        {
+          "before": true,
+          "after": true
+        }
+      ],
+      "object-curly-spacing": [
+        "error",
+        "always"
+      ],
+      "comma-dangle": [
+        "error",
+        "never"
+      ],
+      "no-unreachable": "error",
+      "quotes": [
+        "error",
+        "single"
+      ],
+      "quote-props": [
+        "error",
+        "as-needed"
+      ],
+      "semi": "error",
+      "no-extra-semi": "error",
+      "semi-spacing": "error",
+      "no-spaced-func": "error",
+      "no-throw-literal": "error",
+      "space-before-blocks": "error",
+      "space-before-function-paren": [
+        "error",
+        "never"
+      ],
+      "space-infix-ops": "error",
+      "space-unary-ops": "error",
+      "no-var": "warn",
+      "prefer-const": "warn",
+      "strict": [
+        "error",
+        "global"
+      ],
+      "no-restricted-globals": [
+        "error",
+        {
+          "name": "context",
+          "message": "Don't use Mocha's global context"
+        }
+      ],
+      "no-prototype-builtins": "off",
+      "mocha-no-only/mocha-no-only": [
+        "error"
+      ]
+    }
+  },
+  "funding": {
+    "type": "opencollective",
+    "url": "https://opencollective.com/mongoose"
   }
-},
-"funding": {
-  "type": "opencollective",
-  "url": "https://opencollective.com/mongoose"
-}
 }
\ No newline at end of file

From bf7fcdd889a2214fc0a6e4d60641d93d702a4ec9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 10:17:14 -0400
Subject: [PATCH 2138/2348] fix(index.d.ts): undo some changes for
 VirtualTypeOptions re: #10350

---
 index.d.ts | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 682e73ce4f2..954c35d6783 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1225,13 +1225,13 @@ declare module 'mongoose' {
     statics: { [name: string]: (this: M, ...args: any[]) => any };
 
     /** Creates a virtual type with the given name. */
-    virtual(name: string, options?: VirtualTypeOptions<DocType>): VirtualType<DocType>;
+    virtual(name: string, options?: VirtualTypeOptions): VirtualType;
 
     /** Object of currently defined virtuals on this schema */
     virtuals: any;
 
     /** Returns the virtual type with the given `name`. */
-    virtualpath(name: string): VirtualType<DocType> | null;
+    virtualpath(name: string): VirtualType | null;
   }
 
   type SchemaDefinitionWithBuiltInClass<T extends number | string | boolean | Function> = T extends number
@@ -1618,7 +1618,7 @@ declare module 'mongoose' {
     validator: ValidateFn<T> | LegacyAsyncValidateFn<T> | AsyncValidateFn<T>;
   }
 
-  interface VirtualTypeOptions<D = Document> {
+  interface VirtualTypeOptions {
     /** If `ref` is not nullish, this becomes a populated virtual. */
     ref?: string | Function;
 
@@ -1644,7 +1644,7 @@ declare module 'mongoose' {
     count?: boolean;
 
     /** Add an extra match condition to `populate()`. */
-    match?: FilterQuery<D> | ((doc: D) => FilterQuery<D>);
+    match?: FilterQuery<any> | Function;
 
     /** Add a default `limit` to the `populate()` query. */
     limit?: number;
@@ -1665,21 +1665,18 @@ declare module 'mongoose' {
     options?: QueryOptions;
   }
 
-  class VirtualType<D = Document> {
-    /** VirtualType constructor */
-    constructor(options?: VirtualTypeOptions);
-
+  class VirtualType {
     /** Applies getters to `value`. */
-    applyGetters(value: any, doc: D): any;
+    applyGetters(value: any, doc: Document): any;
 
     /** Applies setters to `value`. */
-    applySetters(value: any, doc: D): any;
+    applySetters(value: any, doc: Document): any;
 
     /** Adds a custom getter to this virtual. */
-    get(fn: (this: D, value: any, virtual: this, doc: D) => any): this;
+    get(fn: Function): this;
 
     /** Adds a custom setter to this virtual. */
-    set(fn: (this: D, value: any, virtual: this, doc: D) => any): this;
+    set(fn: Function): this;
   }
 
   namespace Schema {

From 429c2b0d1d4cdfbf17dc1d745e509991a7786db7 Mon Sep 17 00:00:00 2001
From: Kris Hanus <khanus@vmo.aero>
Date: Tue, 15 Jun 2021 16:17:15 +0000
Subject: [PATCH 2139/2348] check that schema type is an object when setting
 isUnderneathDocArray

---
 lib/schema.js | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index bd7dea3951a..d48fee71719 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -777,12 +777,18 @@ Schema.prototype.path = function(path, obj) {
 
   if (schemaType.$isMongooseDocumentArray) {
     for (const key of Object.keys(schemaType.schema.paths)) {
-      this.subpaths[path + '.' + key] = schemaType.schema.paths[key];
-      schemaType.schema.paths[key].$isUnderneathDocArray = true;
+      const _schemaType = schemaType.schema.paths[key];
+      this.subpaths[path + '.' + key] = _schemaType;
+      if (typeof _schemaType === 'object' && _schemaType != null) {
+        _schemaType.$isUnderneathDocArray = true;
+      }
     }
     for (const key of Object.keys(schemaType.schema.subpaths)) {
-      this.subpaths[path + '.' + key] = schemaType.schema.subpaths[key];
-      schemaType.schema.subpaths[key].$isUnderneathDocArray = true;
+      const _schemaType = schemaType.schema.subpaths[key];
+      this.subpaths[path + '.' + key] = _schemaType;
+      if (typeof _schemaType === 'object' && _schemaType != null) {
+        _schemaType.$isUnderneathDocArray = true;
+      }
     }
     for (const key of Object.keys(schemaType.schema.singleNestedPaths)) {
       const _schemaType = schemaType.schema.singleNestedPaths[key];

From c72b9710bbd463184d10b762347b54a05b998d48 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 12:56:33 -0400
Subject: [PATCH 2140/2348] test(document): repro #10351

---
 test/document.test.js | 31 +++++++++++++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 062695d27a4..9010cb097ba 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10281,12 +10281,10 @@ describe('document', function() {
     return co(function*() {
       const doc = yield Test.create({ _id: Date.now() });
 
-      // It's Ok!
       doc.nested.data.set('second', {});
       assert.ok(doc.modifiedPaths().indexOf('nested.data.second') !== -1, doc.modifiedPaths());
       yield doc.save();
 
-      // It's ERROR!
       doc.nested.data.get('second').data.set('final', 3);
       assert.ok(doc.modifiedPaths().indexOf('nested.data.second.data.final') !== -1, doc.modifiedPaths());
       yield doc.save();
@@ -10295,4 +10293,33 @@ describe('document', function() {
       assert.equal(fromDb.nested.data.second.data.final, 3);
     });
   });
+
+  it('avoids infinite recursion when setting single nested subdoc to array (gh-10351)', function() {
+    const userInfoSchema = new mongoose.Schema({ _id: String }, { _id: false });
+    const observerSchema = new mongoose.Schema({ user: {} }, { _id: false });
+
+    const entrySchema = new mongoose.Schema({
+      creator: userInfoSchema,
+      observers: [observerSchema]
+    });
+
+    entrySchema.pre('save', function(next) {
+      this.observers = [{ user: this.creator }];
+
+      next();
+    });
+
+    const Test = db.model('Test', entrySchema);
+
+    return co(function*() {
+      const entry = new Test({
+        creator: { _id: 'u1' }
+      });
+
+      yield entry.save();
+
+      const fromDb = yield Test.findById(entry);
+      assert.equal(fromDb.observers.length, 1);
+    });
+  });
 });

From e0af551f5a155f9f39b7dee73c7c776136324b0a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 12:57:36 -0400
Subject: [PATCH 2141/2348] fix(document): avoid infinite recursion when
 setting single nested subdoc to array

Fix #10351
---
 lib/document.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 3bc47638093..d85a9ddd2ca 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2928,8 +2928,8 @@ Document.prototype.$__reset = function reset() {
       doc.$__reset();
       if (doc.$__parent === _this) {
         _this.$__.activePaths.init(doc.$basePath);
-      } else if (doc.$__parent != null) {
-        // If map path underneath nested path, may end up with a case where
+      } else if (doc.$__parent != null && doc.$__parent.ownerDocument) {
+        // If map path underneath subdocument, may end up with a case where
         // map path is modified but parent still needs to be reset. See gh-10295
         doc.$__parent.$__reset();
       }

From 4825fd6c737615b018d9679cc8c9b8b91f7b8da7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 14:21:58 -0400
Subject: [PATCH 2142/2348] chore: release 5.12.14

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 2619977a8da..e6dca33d45d 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.12.14 / 2021-06-15
+====================
+ * fix(schema): check that schema type is an object when setting isUnderneathDocArray #10361 [vmo-khanus](https://github.com/vmo-khanus)
+ * fix(document): avoid infinite recursion when setting single nested subdoc to array #10351
+ * fix(populate): allow populating nested path in schema using `Model.populate()` #10335
+ * fix(drivers): emit operation-start/operation-end events to allow inspecting when operations start and end
+ * fix(index.d.ts): improve typings for virtuals #10350 [thiagokisaki](https://github.com/thiagokisaki)
+ * fix(index.d.ts): correct constructor type for Document #10328
+ * fix(index.d.ts): add `ValidationError` as a possible type for `ValidationError#errors` #10320 [IslandRhythms](https://github.com/IslandRhythms)
+ * fix: remove unnecessary async devDependency that's causing npm audit warnings #10281
+ * docs(typescript): add schemas guide #10308
+ * docs(model): add options parameter description to `Model.exists()` #10336 [Aminoiz](https://github.com/Aminoiz)
+
 5.12.13 / 2021-06-04
 ====================
  * perf(document): avoid creating nested paths when running `$getAllSubdocs()` #10275
diff --git a/package.json b/package.json
index d3ddd459e33..8c0dd536f22 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.13",
+  "version": "5.12.14",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 928ca4a842f96583cac916cb14c9217c73f6e276 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 15:37:28 -0400
Subject: [PATCH 2143/2348] fix(index.d.ts): add extra `TInstanceMethods`
 generic param to `Schema` for cases when we can't infer from Model

Fix #10358
---
 index.d.ts | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 954c35d6783..1ab1a0b8e92 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1097,7 +1097,7 @@ declare module 'mongoose' {
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
   type ErrorHandlingMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, err: NativeError, res: ResType, next: (err?: CallbackError) => void) => void;
 
-  class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined> extends events.EventEmitter {
+  class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined, TInstanceMethods = ExtractMethods<M>> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1146,11 +1146,11 @@ declare module 'mongoose' {
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    method(name: string, fn: (this: EnforceDocument<DocType, ExtractMethods<M>>, ...args: any[]) => any, opts?: any): this;
-    method(obj: { [name: string]: (this: EnforceDocument<DocType, ExtractMethods<M>>, ...args: any[]) => any }): this;
+    method(name: string, fn: (this: EnforceDocument<DocType, TInstanceMethods>, ...args: any[]) => any, opts?: any): this;
+    method(obj: { [name: string]: (this: EnforceDocument<DocType, TInstanceMethods>, ...args: any[]) => any }): this;
 
     /** Object of currently defined methods on this schema. */
-    methods: { [name: string]: (this: EnforceDocument<DocType, ExtractMethods<M>>, ...args: any[]) => any };
+    methods: { [name: string]: (this: EnforceDocument<DocType, TInstanceMethods>, ...args: any[]) => any };
 
     /** The original object passed to the schema constructor */
     obj: any;
@@ -1171,8 +1171,8 @@ declare module 'mongoose' {
     plugin(fn: (schema: Schema<DocType, Model<DocType>, SchemaDefinitionType>, opts?: any) => void, opts?: any): this;
 
     /** Defines a post hook for the model. */
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PostMiddlewareFunction<T>): this;
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
+    post<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PostMiddlewareFunction<T>): this;
+    post<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: PostMiddlewareFunction<T>): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: PostMiddlewareFunction<T, Array<any>>): this;
@@ -1180,8 +1180,8 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: PostMiddlewareFunction<T>): this;
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
 
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
-    post<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
@@ -1190,9 +1190,9 @@ declare module 'mongoose' {
     post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
 
     /** Defines a pre hook for the model. */
-    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: 'save', fn: PreSaveMiddlewareFunction<T>): this;
-    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PreMiddlewareFunction<T>): this;
-    pre<T = EnforceDocument<DocType, ExtractMethods<M>>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
+    pre<T = EnforceDocument<DocType, TInstanceMethods>>(method: 'save', fn: PreSaveMiddlewareFunction<T>): this;
+    pre<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: PreMiddlewareFunction<T>): this;
+    pre<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, fn: PreMiddlewareFunction<T>): this;
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: PreMiddlewareFunction<T>): this;
@@ -1201,7 +1201,7 @@ declare module 'mongoose' {
     pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
+    query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType, TInstanceMethods>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;

From 3a937022371b0f751bc05e2bcc8a2b0f49d0ad49 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 16:43:11 -0400
Subject: [PATCH 2144/2348] feat(document): allow passing a list of virtuals to
 apply in `toObject()` and `toJSON()`

Re: #10120
---
 index.d.ts            |  2 +-
 lib/document.js       |  9 +++++++++
 test/document.test.js | 37 +++++++++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 1ab1a0b8e92..ccc9f7c3c51 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1066,7 +1066,7 @@ declare module 'mongoose' {
     /** apply all getters (path and virtual getters) */
     getters?: boolean;
     /** apply virtual getters (can override getters option) */
-    virtuals?: boolean;
+    virtuals?: boolean | string[];
     /** if `options.virtuals = true`, you can set `options.aliases = false` to skip applying aliases. This option is a no-op if `options.virtuals = false`. */
     aliases?: boolean;
     /** remove empty objects (defaults to true) */
diff --git a/lib/document.js b/lib/document.js
index d85a9ddd2ca..4ddc2b4b9dc 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3552,6 +3552,11 @@ function applyVirtuals(self, json, options, toObjectOptions) {
   let v;
   const aliases = get(toObjectOptions, 'aliases', true);
 
+  let virtualsToApply = null;
+  if (Array.isArray(options.virtuals)) {
+    virtualsToApply = new Set(options.virtuals);
+  }
+
   if (!cur) {
     return json;
   }
@@ -3560,6 +3565,10 @@ function applyVirtuals(self, json, options, toObjectOptions) {
   for (i = 0; i < numPaths; ++i) {
     path = paths[i];
 
+    if (virtualsToApply != null && !virtualsToApply.has(path)) {
+      continue;
+    }
+
     // Allow skipping aliases with `toObject({ virtuals: true, aliases: false })`
     if (!aliases && schema.aliases.hasOwnProperty(path)) {
       continue;
diff --git a/test/document.test.js b/test/document.test.js
index 9010cb097ba..65a5b4f9a78 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10322,4 +10322,41 @@ describe('document', function() {
       assert.equal(fromDb.observers.length, 1);
     });
   });
+
+  it('supports passing a list of virtuals to `toObject()` (gh-10120)', function() {
+    const schema = new mongoose.Schema({
+      name: String,
+      age: Number,
+      nested: {
+        test: String
+      }
+    });
+    schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
+    schema.virtual('answer').get(() => 42);
+    schema.virtual('nested.hello').get(() => 'world');
+
+    const Model = db.model('Person', schema);
+
+    const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
+
+    let obj = doc.toObject({ virtuals: true });
+    assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+    assert.equal(obj.answer, 42);
+    assert.equal(obj.nested.hello, 'world');
+
+    obj = doc.toObject({ virtuals: ['answer'] });
+    assert.ok(!obj.nameUpper);
+    assert.equal(obj.answer, 42);
+    assert.equal(obj.nested.hello, null);
+
+    obj = doc.toObject({ virtuals: ['nameUpper'] });
+    assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+    assert.equal(obj.answer, null);
+    assert.equal(obj.nested.hello, null);
+
+    obj = doc.toObject({ virtuals: ['nested.hello'] });
+    assert.equal(obj.nameUpper, null);
+    assert.equal(obj.answer, null);
+    assert.equal(obj.nested.hello, 'world');
+  });
 });

From 7d4eb1121bb769bfa717ece4d177eb12d14c288a Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 15 Jun 2021 16:53:51 -0400
Subject: [PATCH 2145/2348] feat: can now do a dryRun of syncIndexes with
 Model.diffIndexes()

---
 lib/model.js               | 49 ++++++++++++++++++++++++--------------
 test/model.indexes.test.js |  7 +++---
 2 files changed, 35 insertions(+), 21 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 03f2edc3592..cfe7a5dbb06 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1411,27 +1411,40 @@ Model.syncIndexes = function syncIndexes(options, callback) {
   }, this.events);
 };
 
-Model.diffIndexes = function diffIndexes() {
+
+Model.diffIndexes = function diffIndexes(options, callback) {
   const toDrop = [];
   const toCreate = [];
-  // need this.listIndexes to get all
-  // the indexes in mongodb
-  // look at cleanIndexes()
-  // as it seems it is already done ↓
-  // use this.schema.indexes()
-  // to get indexes defined on the schema
-  this.listIndexes((err, indexes) => {
-    console.log('err', err);
-    console.log('indexes', indexes);
-    console.log(this.schema.indexes());
-
-    // Do const schemaIndexes = this.schema.indexes()[0];
-    // for (const key of schemaIndexes)
-    // log the keys first to make sure this is the correct line of thought
-    // use the isDefaultIdIndex() method to check for that
+  callback = this.$handleCallbackError(callback);
+  return this.db.base._promiseOrCallback(callback, cb => {
+    cb = this.$wrapCallback(cb);
+    this.listIndexes((err, indexes) => {
+      const schemaIndexes = this.schema.indexes();
+      for (const index of indexes) {
+        let found = false;
+        // Never try to drop `_id` index, MongoDB server doesn't allow it
+        if (isDefaultIdIndex(index)) {
+          continue;
+        }
+  
+        for (const schemaIndex of schemaIndexes) {
+          const key = schemaIndex[0];
+          const options = _decorateDiscriminatorIndexOptions(this,
+            utils.clone(schemaIndex[1]));
+          if (isIndexEqual(key,options,index)) {
+            found = true;
+          } else {
+            toCreate.push(key);
+          }
+        }
+  
+        if (!found) {
+          toDrop.push(index.name);
+        }
+      }
+      cb(null, {toDrop, toCreate})
+    });
   });
-
-  return { toDrop, toCreate };
 };
 
 /**
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 63bd57a025c..a0a3ede1843 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -683,15 +683,16 @@ describe('model', function() {
         yield User.collection.drop();
       });
     });
-    it('should do a dryRun gh-10316', function() {
+    it('should do a dryRun feat-10316', function() {
       return co(function*() {
         const userSchema = new mongoose.Schema({ username: String }, { password: String }, { email: String });
         userSchema.index({ password: 1 });
         userSchema.index({ email: 1 });
         const User = db.model('User', userSchema);
         yield User.collection.createIndex({ age: 1 });
-        const result = User.diffIndexes();
-        assert.ok(result);
+        const result = yield User.diffIndexes();
+        assert.deepStrictEqual(result.toDrop, ['age_1']);
+        assert.deepStrictEqual(result.toCreate, [{"password": 1},{"email": 1}]);
       });
     });
   });

From beb995cfa233fb07b587eaf987c30618e81774e4 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 15 Jun 2021 16:58:26 -0400
Subject: [PATCH 2146/2348] linter fix

---
 lib/model.js               | 8 ++++----
 test/model.indexes.test.js | 4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index cfe7a5dbb06..79124466cc3 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1426,23 +1426,23 @@ Model.diffIndexes = function diffIndexes(options, callback) {
         if (isDefaultIdIndex(index)) {
           continue;
         }
-  
+
         for (const schemaIndex of schemaIndexes) {
           const key = schemaIndex[0];
           const options = _decorateDiscriminatorIndexOptions(this,
             utils.clone(schemaIndex[1]));
-          if (isIndexEqual(key,options,index)) {
+          if (isIndexEqual(key, options, index)) {
             found = true;
           } else {
             toCreate.push(key);
           }
         }
-  
+
         if (!found) {
           toDrop.push(index.name);
         }
       }
-      cb(null, {toDrop, toCreate})
+      cb(null, { toDrop, toCreate });
     });
   });
 };
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index a0a3ede1843..41334b3e54d 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -688,11 +688,11 @@ describe('model', function() {
         const userSchema = new mongoose.Schema({ username: String }, { password: String }, { email: String });
         userSchema.index({ password: 1 });
         userSchema.index({ email: 1 });
-        const User = db.model('User', userSchema);
+        const User = db.model('Upson', userSchema);
         yield User.collection.createIndex({ age: 1 });
         const result = yield User.diffIndexes();
         assert.deepStrictEqual(result.toDrop, ['age_1']);
-        assert.deepStrictEqual(result.toCreate, [{"password": 1},{"email": 1}]);
+        assert.deepStrictEqual(result.toCreate, [{ 'password': 1 }, { 'email': 1 }]);
       });
     });
   });

From bc6958b6a0ac5da745a4a8109da862c0f5f79c0d Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Tue, 15 Jun 2021 17:00:49 -0400
Subject: [PATCH 2147/2348] linter fix

---
 test/model.indexes.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 41334b3e54d..e129fa1931f 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -692,7 +692,7 @@ describe('model', function() {
         yield User.collection.createIndex({ age: 1 });
         const result = yield User.diffIndexes();
         assert.deepStrictEqual(result.toDrop, ['age_1']);
-        assert.deepStrictEqual(result.toCreate, [{ 'password': 1 }, { 'email': 1 }]);
+        assert.deepStrictEqual(result.toCreate, [{ password: 1 }, { email: 1 }]);
       });
     });
   });

From ac8afd893b3991c07b0fa8381b031324b397a3e3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 15 Jun 2021 17:12:11 -0400
Subject: [PATCH 2148/2348] refactor: remove unnecessary `populate()` code re:
 #8298

---
 lib/document.js | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 5dd7fae6d8a..7d442958f78 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -908,7 +908,6 @@ Document.prototype.overwrite = function overwrite(obj) {
  */
 
 Document.prototype.$set = function $set(path, val, type, options) {
-
   if (utils.isPOJO(type)) {
     options = type;
     type = undefined;
@@ -918,6 +917,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
   const merge = options.merge;
   const adhoc = type && type !== true;
   const constructing = type === true;
+  const typeKey = this.$__schema.options.typeKey;
   let adhocs;
   let keys;
   let i = 0;
@@ -1253,18 +1253,13 @@ Document.prototype.$set = function $set(path, val, type, options) {
 
     let popOpts;
     if (schema.options &&
-        Array.isArray(schema.options[this.$__schema.options.typeKey]) &&
-        schema.options[this.$__schema.options.typeKey].length &&
-        schema.options[this.$__schema.options.typeKey][0].ref &&
-        _isManuallyPopulatedArray(val, schema.options[this.$__schema.options.typeKey][0].ref)) {
-      if (this.ownerDocument) {
-        popOpts = { [populateModelSymbol]: val[0].constructor };
-        this.ownerDocument().populated(this.$__fullPath(path),
-          val.map(function(v) { return v._id; }), popOpts);
-      } else {
-        popOpts = { [populateModelSymbol]: val[0].constructor };
-        this.populated(path, val.map(function(v) { return v._id; }), popOpts);
-      }
+        Array.isArray(schema.options[typeKey]) &&
+        schema.options[typeKey].length &&
+        schema.options[typeKey][0].ref &&
+        _isManuallyPopulatedArray(val, schema.options[typeKey][0].ref)) {
+      popOpts = { [populateModelSymbol]: val[0].constructor };
+      this.populated(path, val.map(function(v) { return v._id; }), popOpts);
+
       for (const doc of val) {
         doc.$__.wasPopulated = true;
       }

From c5ff65571096518a1c92bbd91770f9a17d4f7d40 Mon Sep 17 00:00:00 2001
From: Houssem Chebab <houssemchebeb@gmail.com>
Date: Tue, 15 Jun 2021 23:51:18 +0100
Subject: [PATCH 2149/2348] =?UTF-8?q?fix=20typo=20compatability=20?=
 =?UTF-8?q?=E2=86=92=20compatibility?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 392406c083b..17019f22ac9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2787,7 +2787,7 @@ declare module 'mongoose' {
 
   /** Deprecated types for backwards compatibility. */
 
-  /** Alias for QueryOptions for backwards compatability. */
+  /** Alias for QueryOptions for backwards compatibility. */
   type ModelUpdateOptions = QueryOptions;
 
   type DocumentQuery<ResultType, DocType extends Document, THelpers = {}> = Query<ResultType, DocType, THelpers>;

From 99e29dcc43ac756c9ba93618fab822175d6208b5 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 16 Jun 2021 12:24:34 +0200
Subject: [PATCH 2150/2348] fix(model): make Model.validate(...) object under
 validation be the context by default

---
 lib/model.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 766807577d0..c648589fe43 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -4062,7 +4062,7 @@ Model.aggregate = function aggregate(pipeline, callback) {
  */
 
 Model.validate = function validate(obj, pathsToValidate, context, callback) {
-  if (context === void 0) {
+  if ((arguments.length < 3) || (arguments.length === 3 && typeof arguments[2] === 'function')) {
     // For convenience, if we're validating a document or an object, make `context` default to
     // the model so users don't have to always pass `context`, re: gh-10132, gh-10346
     context = obj;

From 9289972952fd665479d538d626b4ae4d86fed8a8 Mon Sep 17 00:00:00 2001
From: Jim Lynch <mrdotjim@gmail.com>
Date: Wed, 16 Jun 2021 13:01:23 -0400
Subject: [PATCH 2151/2348] Update transactions.md

---
 docs/transactions.md | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/docs/transactions.md b/docs/transactions.md
index 75f2fecc964..016537eb9fe 100644
--- a/docs/transactions.md
+++ b/docs/transactions.md
@@ -7,6 +7,11 @@ This guide will get you started using transactions with Mongoose.
 
 <h2 id="getting-started-with-transactions"><a href="#getting-started-with-transactions">Getting Started with Transactions</a></h2>
 
+If you haven't already, import mongoose:
+```javascript
+import mongoose from 'mongoose';
+```
+
 To create a transaction, you first need to create a session using or [`Mongoose#startSession`](/docs/api/mongoose.html#mongoose_Mongoose-startSession)
 or [`Connection#startSession()`](/docs/api/connection.html#connection_Connection-startSession).
 
@@ -73,4 +78,4 @@ You can also use `session.abortTransaction()` to abort a transaction:
 
 ```javascript
 [require:transactions.*abort]
-```
\ No newline at end of file
+```

From 009b0c39e8acefe3ba65ffe7071f8a830c02bf12 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Jun 2021 13:19:45 -0400
Subject: [PATCH 2152/2348] feat(query): add `sanitizeProjection` option to opt
 in to automatically sanitizing untrusted query projections

Fix #10243
---
 index.d.ts                              |  3 ++-
 lib/helpers/query/sanitizeProjection.js | 14 ++++++++++++++
 lib/query.js                            | 24 ++++++++++++++++++++++--
 lib/validoptions.js                     |  1 +
 test/query.test.js                      | 14 ++++++++++++++
 5 files changed, 53 insertions(+), 3 deletions(-)
 create mode 100644 lib/helpers/query/sanitizeProjection.js

diff --git a/index.d.ts b/index.d.ts
index ccc9f7c3c51..50bb2699c8e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -929,6 +929,7 @@ declare module 'mongoose' {
      */
     returnDocument?: string;
     runValidators?: boolean;
+    sanitizeProjection?: boolean;
     /** The session associated with this query. */
     session?: mongodb.ClientSession;
     setDefaultsOnInsert?: boolean;
@@ -949,7 +950,7 @@ declare module 'mongoose' {
     writeConcern?: any;
   }
 
-  type MongooseQueryOptions = Pick<QueryOptions, 'populate' | 'lean' | 'omitUndefined' | 'strict' | 'useFindAndModify'>;
+  type MongooseQueryOptions = Pick<QueryOptions, 'populate' | 'lean' | 'omitUndefined' | 'strict' | 'useFindAndModify' | 'sanitizeProjection'>;
 
   interface SaveOptions {
     checkKeys?: boolean;
diff --git a/lib/helpers/query/sanitizeProjection.js b/lib/helpers/query/sanitizeProjection.js
new file mode 100644
index 00000000000..dcb61fba910
--- /dev/null
+++ b/lib/helpers/query/sanitizeProjection.js
@@ -0,0 +1,14 @@
+'use strict';
+
+module.exports = function sanitizeProjection(projection) {
+  if (projection == null) {
+    return;
+  }
+
+  const keys = Object.keys(projection);
+  for (let i = 0; i < keys.length; ++i) {
+    if (typeof projection[keys[i]] === 'string') {
+      projection[keys[i]] = 1;
+    }
+  }
+};
\ No newline at end of file
diff --git a/lib/query.js b/lib/query.js
index 7497425c650..1c4a938a08d 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -28,6 +28,7 @@ const isInclusive = require('./helpers/projection/isInclusive');
 const mquery = require('mquery');
 const parseProjection = require('./helpers/projection/parseProjection');
 const removeUnusedArrayFilters = require('./helpers/update/removeUnusedArrayFilters');
+const sanitizeProjection = require('./helpers/query/sanitizeProjection');
 const selectPopulatedFields = require('./helpers/query/selectPopulatedFields');
 const setDefaultsOnInsert = require('./helpers/setDefaultsOnInsert');
 const slice = require('sliced');
@@ -957,13 +958,24 @@ Query.prototype.select = function select() {
 
   const fields = this._fields || (this._fields = {});
   const userProvidedFields = this._userProvidedFields || (this._userProvidedFields = {});
+  let sanitizeProjection = undefined;
+  if (utils.hasUserDefinedProperty(this.model.db.options, 'sanitizeProjection')) {
+    sanitizeProjection = this.model.db.options.sanitizeProjection;
+  } else if (utils.hasUserDefinedProperty(this.model.base.options, 'sanitizeProjection')) {
+    sanitizeProjection = this.model.base.options.sanitizeProjection;
+  } else {
+    sanitizeProjection = this._mongooseOptions.sanitizeProjection;
+  }
 
   arg = parseProjection(arg);
 
   if (utils.isObject(arg)) {
     const keys = Object.keys(arg);
     for (let i = 0; i < keys.length; ++i) {
-      const value = arg[keys[i]];
+      let value = arg[keys[i]];
+      if (typeof value === 'string' && sanitizeProjection) {
+        value = 1;
+      }
       fields[keys[i]] = value;
       userProvidedFields[keys[i]] = value;
     }
@@ -1368,6 +1380,7 @@ Query.prototype.getOptions = function() {
  * - [lean](./api.html#query_Query-lean)
  * - [populate](/docs/populate.html)
  * - [projection](/docs/api/query.html#query_Query-projection)
+ * - sanitizeProjection
  *
  * The following options are only for all operations **except** `update()`, `updateOne()`, `updateMany()`, `remove()`, `deleteOne()`, and `deleteMany()`:
  *
@@ -1390,7 +1403,6 @@ Query.prototype.getOptions = function() {
  */
 
 Query.prototype.setOptions = function(options, overwrite) {
-
   // overwrite is only for internal use
   if (overwrite) {
     // ensure that _mongooseOptions & options are two different objects
@@ -1434,6 +1446,14 @@ Query.prototype.setOptions = function(options, overwrite) {
     this._mongooseOptions.overwriteDiscriminatorKey = options.overwriteDiscriminatorKey;
     delete options.overwriteDiscriminatorKey;
   }
+  if ('sanitizeProjection' in options) {
+    if (options.sanitizeProjection && !this._mongooseOptions.sanitizeProjection) {
+      sanitizeProjection(this._fields);
+    }
+
+    this._mongooseOptions.sanitizeProjection = options.sanitizeProjection;
+    delete options.sanitizeProjection;
+  }
 
   if ('defaults' in options) {
     this._mongooseOptions.defaults = options.defaults;
diff --git a/lib/validoptions.js b/lib/validoptions.js
index fb47f316a8f..836eadbf5c3 100644
--- a/lib/validoptions.js
+++ b/lib/validoptions.js
@@ -19,6 +19,7 @@ const VALID_OPTIONS = Object.freeze([
   'overwriteModels',
   'returnOriginal',
   'runValidators',
+  'sanitizeProjection',
   'selectPopulatedPaths',
   'setDefaultsOnInsert',
   'strict',
diff --git a/test/query.test.js b/test/query.test.js
index 3a428a61439..8762239a910 100644
--- a/test/query.test.js
+++ b/test/query.test.js
@@ -3800,4 +3800,18 @@ describe('Query', function() {
       yield entry.save();
     });
   });
+
+  it('sanitizeProjection option (gh-10243)', function() {
+    const MySchema = Schema({ name: String, email: String });
+    const Test = db.model('Test', MySchema);
+
+    let q = Test.find().select({ email: '$name' });
+    assert.deepEqual(q._fields, { email: '$name' });
+
+    q = Test.find().setOptions({ sanitizeProjection: true }).select({ email: '$name' });
+    assert.deepEqual(q._fields, { email: 1 });
+
+    q = Test.find().select({ email: '$name' }).setOptions({ sanitizeProjection: true });
+    assert.deepEqual(q._fields, { email: 1 });
+  });
 });

From c4b34c63f5849869d915d401c69afc320712219a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Jun 2021 13:25:35 -0400
Subject: [PATCH 2153/2348] test: fix tests re: #10243

---
 lib/query.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/query.js b/lib/query.js
index 1c4a938a08d..fee31ad7ffd 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -959,9 +959,9 @@ Query.prototype.select = function select() {
   const fields = this._fields || (this._fields = {});
   const userProvidedFields = this._userProvidedFields || (this._userProvidedFields = {});
   let sanitizeProjection = undefined;
-  if (utils.hasUserDefinedProperty(this.model.db.options, 'sanitizeProjection')) {
+  if (this.model != null && utils.hasUserDefinedProperty(this.model.db.options, 'sanitizeProjection')) {
     sanitizeProjection = this.model.db.options.sanitizeProjection;
-  } else if (utils.hasUserDefinedProperty(this.model.base.options, 'sanitizeProjection')) {
+  } else if (this.model != null && utils.hasUserDefinedProperty(this.model.base.options, 'sanitizeProjection')) {
     sanitizeProjection = this.model.base.options.sanitizeProjection;
   } else {
     sanitizeProjection = this._mongooseOptions.sanitizeProjection;

From dd5313166e7a7384fd5d9c2b26ea62b32799c90c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Jun 2021 14:53:53 -0400
Subject: [PATCH 2154/2348] feat(document): avoid using sessions that have
 ended, so you can use documents that were loaded in the session after calling
 `endSession()`

Fix #10306
---
 lib/document.js                       | 10 ++++++++++
 test/es-next/transactions.test.es6.js | 16 ++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 7d442958f78..c46260c97b2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -846,8 +846,18 @@ Document.prototype.replaceOne = function replaceOne() {
 
 Document.prototype.$session = function $session(session) {
   if (arguments.length === 0) {
+    if (this.$__.session != null && this.$__.session.hasEnded) {
+      this.$__.session = null;
+      return null;
+    }
     return this.$__.session;
   }
+
+  if (session != null && session.hasEnded) {
+    throw new MongooseError('Cannot set a document\'s session to a session that has ended. Make sure you haven\'t ' +
+      'called `endSession()` on the session you are passing to `$session()`.');
+  }
+
   this.$__.session = session;
 
   if (!this.ownerDocument) {
diff --git a/test/es-next/transactions.test.es6.js b/test/es-next/transactions.test.es6.js
index bbf05bdde70..c12bb7af763 100644
--- a/test/es-next/transactions.test.es6.js
+++ b/test/es-next/transactions.test.es6.js
@@ -439,4 +439,20 @@ describe('transactions', function() {
       { readPreference: 'primary' }
     );
   });
+
+  it('does not throw an error if using document after session has ended (gh-10306)', async function () {
+    const schema = Schema({ arr: [String] });
+
+    const Test = db.model('new_doc_array3', schema);
+
+    await Test.createCollection();
+
+    const session = await db.startSession();
+
+    const doc = new Test({ arr: ['foo'] });
+    doc.$session(session);
+    await session.endSession();
+
+    await doc.save();
+  });
 });

From b79a5695ce51e6f879b447d5a4e7a8398cccc88f Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 16 Jun 2021 16:55:10 -0400
Subject: [PATCH 2155/2348] made requested changes

---
 lib/model.js               | 4 +++-
 test/model.indexes.test.js | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 79124466cc3..b02087f920f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1434,7 +1434,9 @@ Model.diffIndexes = function diffIndexes(options, callback) {
           if (isIndexEqual(key, options, index)) {
             found = true;
           } else {
-            toCreate.push(key);
+            if (toCreate.indexOf(key) === -1) {
+              toCreate.push(key);
+            }
           }
         }
 
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index e129fa1931f..2b69e1f8146 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -690,8 +690,10 @@ describe('model', function() {
         userSchema.index({ email: 1 });
         const User = db.model('Upson', userSchema);
         yield User.collection.createIndex({ age: 1 });
+        yield User.collection.createIndex({ weight: 1 });
+        yield User.init();
         const result = yield User.diffIndexes();
-        assert.deepStrictEqual(result.toDrop, ['age_1']);
+        assert.deepStrictEqual(result.toDrop, ['age_1', 'weight_1']);
         assert.deepStrictEqual(result.toCreate, [{ password: 1 }, { email: 1 }]);
       });
     });

From c6ffe497d22fd0106d0c381c4663a26c04b87256 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 16 Jun 2021 17:31:01 -0400
Subject: [PATCH 2156/2348] made requested changes

---
 lib/model.js               | 22 ++++++++++++++++++----
 test/model.indexes.test.js |  4 ++--
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index b02087f920f..3160c9c93cb 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1433,10 +1433,6 @@ Model.diffIndexes = function diffIndexes(options, callback) {
             utils.clone(schemaIndex[1]));
           if (isIndexEqual(key, options, index)) {
             found = true;
-          } else {
-            if (toCreate.indexOf(key) === -1) {
-              toCreate.push(key);
-            }
           }
         }
 
@@ -1444,6 +1440,24 @@ Model.diffIndexes = function diffIndexes(options, callback) {
           toDrop.push(index.name);
         }
       }
+
+      for (const schemaIndex of schemaIndexes) {
+        const key = schemaIndex[0];
+        let found = false;
+        const options = _decorateDiscriminatorIndexOptions(this,
+          utils.clone(schemaIndex[1]));
+        for (const index of indexes) {
+          if (isDefaultIdIndex(index)) {
+            continue;
+          }
+          if (isIndexEqual(key, options, index)) {
+            found = true;
+          }
+        }
+        if (!found) {
+          toCreate.push(key);
+        }
+      }
       cb(null, { toDrop, toCreate });
     });
   });
diff --git a/test/model.indexes.test.js b/test/model.indexes.test.js
index 2b69e1f8146..e00e52c08bf 100644
--- a/test/model.indexes.test.js
+++ b/test/model.indexes.test.js
@@ -686,12 +686,12 @@ describe('model', function() {
     it('should do a dryRun feat-10316', function() {
       return co(function*() {
         const userSchema = new mongoose.Schema({ username: String }, { password: String }, { email: String });
-        userSchema.index({ password: 1 });
-        userSchema.index({ email: 1 });
         const User = db.model('Upson', userSchema);
         yield User.collection.createIndex({ age: 1 });
         yield User.collection.createIndex({ weight: 1 });
         yield User.init();
+        userSchema.index({ password: 1 });
+        userSchema.index({ email: 1 });
         const result = yield User.diffIndexes();
         assert.deepStrictEqual(result.toDrop, ['age_1', 'weight_1']);
         assert.deepStrictEqual(result.toCreate, [{ password: 1 }, { email: 1 }]);

From 7b514436975950ca13e31052722460cd4aa77bf2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 16 Jun 2021 17:56:05 -0400
Subject: [PATCH 2157/2348] fix(index.d.ts): allow passing arbitrary object as
 `replacement` parameter to `replaceOne()` in TypeScript

Re: #10359
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index e127e97a3a5..d22db916684 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -566,6 +566,7 @@ declare module 'mongoose' {
 
     /** Sends a replaceOne command with this document `_id` as the query selector. */
     replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, this>;
+    replaceOne(replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, this>;
 
     /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
     save(options?: SaveOptions): Promise<this>;
@@ -859,6 +860,7 @@ declare module 'mongoose' {
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
     replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -2237,6 +2239,7 @@ declare module 'mongoose' {
      * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
      */
     replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
 
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;

From 0641a3ea2f0e16161c921b8ef7f291e065883a9e Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 16 Jun 2021 18:01:20 -0400
Subject: [PATCH 2158/2348] added test

---
 test/document.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 5ad1e5a68e5..b24db69073b 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10360,6 +10360,27 @@ describe('document', function() {
     assert.equal(obj.nested.hello, 'world');
   });
 
+  it('adds support for `pathsToSkip` for virtuals feat-10120', function() {
+    const schema = new mongoose.Schema({
+      name: String,
+      age: Number,
+      nested: {
+        test: String
+      }
+    });
+    schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
+    schema.virtual('answer').get(() => 42);
+    schema.virtual('nested.hello').get(() => 'world');
+
+    const Model = db.model('Person', schema);
+    const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
+    const obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
+    assert.ok(obj.nameUpper);
+    assert.equal(obj.answer, null);
+    assert.equal(obj.nested.hello, 'world');
+
+  });
+
   it('support `pathsToSkip` option for `validate()` (feat-10230)', function() {
     const schema = Schema({
       name: {

From c5e6485fb95b6cd6f934b1f78c350037e3cf1ee4 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 17 Jun 2021 14:45:48 -0400
Subject: [PATCH 2159/2348] fortified test and impleneted pathsToSkip for
 virtuals

---
 lib/document.js       | 9 +++++++++
 test/document.test.js | 6 +++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index c46260c97b2..7838681b04d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3575,6 +3575,14 @@ function applyVirtuals(self, json, options, toObjectOptions) {
   if (Array.isArray(options.virtuals)) {
     virtualsToApply = new Set(options.virtuals);
   }
+  else if (options.virtuals.pathsToSkip) {
+    virtualsToApply = new Set(paths);
+    for (let i = 0; i < options.virtuals.pathsToSkip.length; i++) {
+      if (virtualsToApply.has(options.virtuals.pathsToSkip[i])) {
+        virtualsToApply.delete(options.virtuals.pathsToSkip[i]);
+      }
+    }
+  }
 
   if (!cur) {
     return json;
@@ -3620,6 +3628,7 @@ function applyVirtuals(self, json, options, toObjectOptions) {
   return json;
 }
 
+
 /*!
  * Applies virtuals properties to `json`.
  *
diff --git a/test/document.test.js b/test/document.test.js
index b24db69073b..3ce320fc88e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10374,10 +10374,14 @@ describe('document', function() {
 
     const Model = db.model('Person', schema);
     const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
-    const obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
+    let obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
     assert.ok(obj.nameUpper);
     assert.equal(obj.answer, null);
     assert.equal(obj.nested.hello, 'world');
+    obj = doc.toObject({ virtuals: { pathsToSkip: ['nested.hello'] } });
+    assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+    assert.equal(obj.answer, 42);
+    assert.equal(obj.nested.hello, null);
 
   });
 

From 2992d109e43e0560ada9c6447681f5da2910e054 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 17 Jun 2021 14:54:34 -0400
Subject: [PATCH 2160/2348] added critical check

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 7838681b04d..0cbf2271507 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -3575,7 +3575,7 @@ function applyVirtuals(self, json, options, toObjectOptions) {
   if (Array.isArray(options.virtuals)) {
     virtualsToApply = new Set(options.virtuals);
   }
-  else if (options.virtuals.pathsToSkip) {
+  else if (options.virtuals && options.virtuals.pathsToSkip) {
     virtualsToApply = new Set(paths);
     for (let i = 0; i < options.virtuals.pathsToSkip.length; i++) {
       if (virtualsToApply.has(options.virtuals.pathsToSkip[i])) {

From c056a0033ea617068ae1fc5e8412ab12902bc614 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 17 Jun 2021 15:54:26 -0400
Subject: [PATCH 2161/2348] added comments

---
 lib/model.js | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 3160c9c93cb..1482c7fb1bc 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1411,6 +1411,16 @@ Model.syncIndexes = function syncIndexes(options, callback) {
   }, this.events);
 };
 
+/**
+ * Does a dry-run of Model.syncIndexes(), meaning that
+ * the result of this function would be the result of
+ * Model.syncIndexes().
+ * 
+ * 
+ * @param {Object} options not used at all.
+ * @param {Function} callback optional callback
+ * @returns {Object} {toDrop, toCreate} Indexes that would be dropped in mongodb and indexes that would be created in mongodb.
+ */
 
 Model.diffIndexes = function diffIndexes(options, callback) {
   const toDrop = [];
@@ -1420,6 +1430,8 @@ Model.diffIndexes = function diffIndexes(options, callback) {
     cb = this.$wrapCallback(cb);
     this.listIndexes((err, indexes) => {
       const schemaIndexes = this.schema.indexes();
+      // Iterate through the indexes created in mongodb and
+      // compare against the indexes in the schema.
       for (const index of indexes) {
         let found = false;
         // Never try to drop `_id` index, MongoDB server doesn't allow it
@@ -1440,7 +1452,8 @@ Model.diffIndexes = function diffIndexes(options, callback) {
           toDrop.push(index.name);
         }
       }
-
+      // Iterate through the indexes created on the schema and
+      // compare against the indexes in mongodb.
       for (const schemaIndex of schemaIndexes) {
         const key = schemaIndex[0];
         let found = false;

From 2af1e76ac1ea4e2c9a803179ca17b8cb34da8247 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 17 Jun 2021 15:55:30 -0400
Subject: [PATCH 2162/2348] Update model.js

---
 lib/model.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/model.js b/lib/model.js
index 1482c7fb1bc..bf0bb154114 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1419,7 +1419,8 @@ Model.syncIndexes = function syncIndexes(options, callback) {
  * 
  * @param {Object} options not used at all.
  * @param {Function} callback optional callback
- * @returns {Object} {toDrop, toCreate} Indexes that would be dropped in mongodb and indexes that would be created in mongodb.
+ * @returns {Promise} which containts an object, {toDrop, toCreate}, which
+ * are indexes that would be dropped in mongodb and indexes that would be created in mongodb.
  */
 
 Model.diffIndexes = function diffIndexes(options, callback) {

From 74c5c1b049f00ce0758d553d7b2ad45045af43a2 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Thu, 17 Jun 2021 15:57:44 -0400
Subject: [PATCH 2163/2348] linter fix

---
 lib/model.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index bf0bb154114..dfb0792e0e7 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1415,8 +1415,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
  * Does a dry-run of Model.syncIndexes(), meaning that
  * the result of this function would be the result of
  * Model.syncIndexes().
- * 
- * 
+ *
  * @param {Object} options not used at all.
  * @param {Function} callback optional callback
  * @returns {Promise} which containts an object, {toDrop, toCreate}, which

From def42bc471f81c681eea04450573670e29566e30 Mon Sep 17 00:00:00 2001
From: Gurkirat Singh <tbhaxor@gmail.com>
Date: Sat, 19 Jun 2021 17:04:22 +0530
Subject: [PATCH 2164/2348] added typings for near() in model aggregation

---
 index.d.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index d22db916684..c3a5169105f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2562,6 +2562,12 @@ declare module 'mongoose' {
      */
     model(model: any): this;
 
+    /**
+     * Append a new $near operator to this aggregation pipeline
+     * @param arg $near operator contents
+     */
+    near(arg: { near?: number[]; distanceField: string; maxDistance?: number; query?: Record<string, any>; includeLocs?: string; num?: number; uniqueDocs?: boolean }): this;
+
     /** Returns the current pipeline */
     pipeline(): any[];
 

From 798e0f5b51a706820686305d8c883e2eac001b9a Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 16:24:25 +0200
Subject: [PATCH 2165/2348] test(model): add tests re #10353

---
 test/document.test.js | 62 ++++++++++++++++++++++++++++++-------------
 1 file changed, 44 insertions(+), 18 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 5fce68a2383..22ee3743fd7 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10256,28 +10256,54 @@ describe('document', function() {
       assert.equal(validatorCallCount, 0);
     });
   });
-  it('support `pathsToSkip` option for `validate()` (feat-10230)', function() {
-    const schema = Schema({
-      name: {
-        type: String,
-        required: true
-      },
-      age: {
-        type: Number,
-        required: true
-      },
-      rank: String
+
+  describe('pathsToSkip (gh-10230)', () => {
+    it('support `pathsToSkip` option for `Document#validate()`', function() {
+      return co(function*() {
+        const User = getUserModel();
+        const user = new User();
+
+        const err1 = yield user.validate({ pathsToSkip: ['age'] }).then(() => null, err => err);
+        assert.deepEqual(Object.keys(err1.errors), ['name']);
+
+        const err2 = yield user.validate({ pathsToSkip: ['name'] }).then(() => null, err => err);
+        assert.deepEqual(Object.keys(err2.errors), ['age']);
+      });
     });
-    const Model = db.model('Test', schema);
 
-    return co(function*() {
-      const doc = new Model({});
+    it('support `pathsToSkip` option for `Document#validateSync()`', () => {
+      const User = getUserModel();
 
-      let err = yield doc.validate({ pathsToSkip: ['age'] }).catch(err => err);
-      assert.deepEqual(Object.keys(err.errors), ['name']);
+      const user = new User();
 
-      err = yield doc.validate({ pathsToSkip: ['name'] }).catch(err => err);
-      assert.deepEqual(Object.keys(err.errors), ['age']);
+      const err1 = user.validateSync({ pathsToSkip: ['age'] });
+      assert.deepEqual(Object.keys(err1.errors), ['name']);
+
+      const err2 = user.validateSync({ pathsToSkip: ['name'] });
+      assert.deepEqual(Object.keys(err2.errors), ['age']);
+    });
+
+    it('support `pathsToSkip` option for `Model.validate()`', () => {
+      return co(function*() {
+        const User = getUserModel();
+        const err1 = yield User.validate({}, { pathsToSkip: ['age'] });
+        assert.deepEqual(Object.keys(err1.errors), ['name']);
+
+        const err2 = yield User.validate({}, { pathsToSkip: ['name'] });
+        assert.deepEqual(Object.keys(err2.errors), ['age']);
+      });
     });
+
+    function getUserModel() {
+      const userSchema = Schema({
+        name: { type: String, required: true },
+        age: { type: Number, required: true },
+        rank: String
+      });
+
+      const User = db.model('User', userSchema);
+      return User;
+    }
   });
+
 });

From 0754086671d0b91cc67b7c04900a816f90cadbda Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 16:27:38 +0200
Subject: [PATCH 2166/2348] refactor: prefer step-down style over arrow
 function definition

---
 lib/document.js | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 8725d695f73..d7fbd21aff7 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2481,17 +2481,11 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   const validated = {};
   let total = 0;
 
-  const complete = function() {
-    const error = _complete();
-    if (error) {
-      return _this.$__schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
-        callback(error);
-      });
-    }
-    callback(null, _this);
-  };
+  for (const path of paths) {
+    validatePath(path);
+  }
 
-  const validatePath = function(path) {
+  function validatePath(path) {
     if (path == null || validated[path]) {
       return;
     }
@@ -2547,12 +2541,18 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
         --total || complete();
       }, scope, doValidateOptions);
     });
-  };
+  }
 
-  const numPaths = paths.length;
-  for (let i = 0; i < numPaths; ++i) {
-    validatePath(paths[i]);
+  function complete() {
+    const error = _complete();
+    if (error) {
+      return _this.$__schema.s.hooks.execPost('validate:error', _this, [_this], { error: error }, function(error) {
+        callback(error);
+      });
+    }
+    callback(null, _this);
   }
+
 };
 
 /*!

From fefd6577d4b7ef0e1e040bf536c35aa4cb4f9e0f Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 16:32:00 +0200
Subject: [PATCH 2167/2348] refactor: remove duplicate check for
 pathsToValidate when string

---
 lib/document.js | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d7fbd21aff7..5da4538f3c4 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2651,9 +2651,6 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     pathDetails[0];
   const skipSchemaValidators = pathDetails[1];
 
-  if (typeof pathsToValidate === 'string') {
-    pathsToValidate = pathsToValidate.split(' ');
-  }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   }

From cd825578b9e876457c337979fa2eda43c8e209d0 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 16:58:23 +0200
Subject: [PATCH 2168/2348] test: assert pathsToSkip space separated works

---
 lib/document.js       | 11 ++++++++++-
 test/document.test.js | 22 +++++++++++++++++++++-
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 5da4538f3c4..a7155b70131 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2244,6 +2244,9 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
     options = pathsToValidate;
     pathsToValidate = null;
   }
+  if (options && typeof options.pathsToSkip === 'string') {
+    options.pathsToSkip = options.pathsToSkip.split(' ');
+  }
 
   return promiseOrCallback(callback, cb => {
     if (parallelValidate != null) {
@@ -2591,7 +2594,6 @@ function _handlePathsToValidate(paths, pathsToValidate) {
 /*!
  * ignore
  */
-
 function _handlePathsToSkip(paths, pathsToSkip) {
   pathsToSkip = new Set(pathsToSkip);
   paths = paths.filter(p => !pathsToSkip.has(p));
@@ -2640,8 +2642,12 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     shouldValidateModifiedOnly = this.$__schema.options.validateModifiedOnly;
   }
 
+  let pathsToSkip = get(options, 'pathsToSkip');
+
   if (typeof pathsToValidate === 'string') {
     pathsToValidate = pathsToValidate.split(' ');
+  } else if (typeof pathsToSkip === 'string') {
+    pathsToSkip = pathsToSkip.split(' ');
   }
 
   // only validate required fields when necessary
@@ -2653,6 +2659,9 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
 
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
+  } else if (Array.isArray(pathsToSkip)) {
+    const pathsToValidateByExclusion = _handlePathsToSkip(paths, pathsToSkip);
+    paths = _handlePathsToValidate(paths, pathsToValidateByExclusion);
   }
   const validating = {};
 
diff --git a/test/document.test.js b/test/document.test.js
index 22ee3743fd7..87caa84c3e7 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10283,7 +10283,8 @@ describe('document', function() {
       assert.deepEqual(Object.keys(err2.errors), ['age']);
     });
 
-    it('support `pathsToSkip` option for `Model.validate()`', () => {
+    // skip until gh-10367 is implemented
+    xit('support `pathsToSkip` option for `Model.validate()`', () => {
       return co(function*() {
         const User = getUserModel();
         const err1 = yield User.validate({}, { pathsToSkip: ['age'] });
@@ -10293,6 +10294,25 @@ describe('document', function() {
         assert.deepEqual(Object.keys(err2.errors), ['age']);
       });
     });
+    it('`pathsToSkip` accepts space separated paths', () => {
+      const userSchema = Schema({
+        name: { type: String, required: true },
+        age: { type: Number, required: true },
+        country: { type: String, required: true },
+        rank: { type: String, required: true }
+      });
+
+      const User = db.model('User', userSchema);
+      return co(function* () {
+        const user = new User({ name: 'Sam', age: 26 });
+
+        const err1 = user.validateSync(null, { pathsToSkip: 'country rank' });
+        assert.ok(err1 == null);
+
+        const err2 = yield user.validate({ pathsToSkip: 'country rank' }).then(() => null, err => err);
+        assert.ok(err2 == null);
+      });
+    });
 
     function getUserModel() {
       const userSchema = Schema({

From a7299f10570e8d8dc166aa1d7846b4ecc7987eaf Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 17:02:14 +0200
Subject: [PATCH 2169/2348] use paths from handlePathsToSkip directly

---
 lib/document.js | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index a7155b70131..d07e83649f3 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2465,8 +2465,7 @@ Document.prototype.$__validate = function(pathsToValidate, options, callback) {
   }
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
-  }
-  else if (pathsToSkip) {
+  } else if (pathsToSkip) {
     paths = _handlePathsToSkip(paths, pathsToSkip);
   }
   if (paths.length === 0) {
@@ -2660,8 +2659,7 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
   if (Array.isArray(pathsToValidate)) {
     paths = _handlePathsToValidate(paths, pathsToValidate);
   } else if (Array.isArray(pathsToSkip)) {
-    const pathsToValidateByExclusion = _handlePathsToSkip(paths, pathsToSkip);
-    paths = _handlePathsToValidate(paths, pathsToValidateByExclusion);
+    paths = _handlePathsToSkip(paths, pathsToSkip);
   }
   const validating = {};
 

From 087025cb2b202a23ef596cbed61bdec2ceaa0ac7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 17:47:25 +0200
Subject: [PATCH 2170/2348] docs(Document): add paths and pathsToSkip to JSDoc
 and index.d.ts

---
 index.d.ts                  | 13 ++++++++++---
 lib/document.js             |  2 ++
 test/document.test.js       |  2 +-
 test/typescript/document.ts |  9 ++++++++-
 4 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index a7024d5ef7b..8a29914d750 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -598,15 +598,22 @@ declare module 'mongoose' {
     updateOne(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
 
     /** Executes registered validation rules for this document. */
-    validate(pathsToValidate?: Array<string>, options?: any): Promise<void>;
+    validate(options:{ pathsToSkip?: pathsToSkip }): Promise<void>;
+    validate(pathsToValidate?: pathsToValidate, options?: any): Promise<void>;
     validate(callback: (err: CallbackError) => void): void;
-    validate(pathsToValidate: Array<string>, callback: (err: CallbackError) => void): void;
-    validate(pathsToValidate: Array<string>, options: any, callback: (err: CallbackError) => void): void;
+    validate(pathsToValidate: pathsToValidate, callback: (err: CallbackError) => void): void;
+    validate(pathsToValidate: pathsToValidate, options: any, callback: (err: CallbackError) => void): void;
 
     /** Executes registered validation rules (skipping asynchronous validators) for this document. */
+    validateSync(options:{pathsToSkip?: pathsToSkip, [k:string]: any }): Error.ValidationError | null;
     validateSync(pathsToValidate?: Array<string>, options?: any): Error.ValidationError | null;
   }
 
+  /** A list of paths to validate. If set, Mongoose will validate only the modified paths that are in the given list. */
+  type pathsToValidate = string[] | string;
+  /** A list of paths to skip. If set, Mongoose will validate every modified path that is not in this list. */
+  type pathsToSkip = string[] | string;
+
   interface AcceptsDiscriminator {
     /** Adds a discriminator type. */
     discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string | number | ObjectId): Model<D>;
diff --git a/lib/document.js b/lib/document.js
index d07e83649f3..ec316807dfe 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2205,6 +2205,7 @@ Document.prototype.isDirectSelected = function isDirectSelected(path) {
  * @param {Array|String} [pathsToValidate] list of paths to validate. If set, Mongoose will validate only the modified paths that are in the given list.
  * @param {Object} [options] internal options
  * @param {Boolean} [options.validateModifiedOnly=false] if `true` mongoose validates only modified paths.
+ * @param {Array|string} [options.pathsToSkip] list of paths to skip. If set, Mongoose will validate every modified path that is not in this list.
  * @param {Function} [callback] optional callback called after validation completes, passing an error if one occurred
  * @return {Promise} Promise
  * @api public
@@ -2618,6 +2619,7 @@ function _handlePathsToSkip(paths, pathsToSkip) {
  * @param {Array|string} pathsToValidate only validate the given paths
  * @param {Object} [options] options for validation
  * @param {Boolean} [options.validateModifiedOnly=false] If `true`, Mongoose will only validate modified paths, as opposed to modified paths and `required` paths.
+ * @param {Array|string} [options.pathsToSkip] list of paths to skip. If set, Mongoose will validate every modified path that is not in this list.
  * @return {ValidationError|undefined} ValidationError if there are errors during validation, or undefined if there is no error.
  * @api public
  */
diff --git a/test/document.test.js b/test/document.test.js
index 87caa84c3e7..1c38862349a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10306,7 +10306,7 @@ describe('document', function() {
       return co(function* () {
         const user = new User({ name: 'Sam', age: 26 });
 
-        const err1 = user.validateSync(null, { pathsToSkip: 'country rank' });
+        const err1 = user.validateSync({ pathsToSkip: 'country rank' });
         assert.ok(err1 == null);
 
         const err2 = yield user.validate({ pathsToSkip: 'country rank' }).then(() => null, err => err);
diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index 0db7014ac54..37dfbb8b62d 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -15,4 +15,11 @@ void async function main() {
 
   const p: Promise<ITest> = doc.remove();
   await p;
-}();
\ No newline at end of file
+}();
+
+
+const test = new Test();
+test.validate({ pathsToSkip: ['hello'] });
+test.validate({ pathsToSkip: 'name age' });
+test.validateSync({ pathsToSkip: ['name', 'age'] });
+test.validateSync({ pathsToSkip: 'name age' });
\ No newline at end of file

From 1dd21a73e99a5fbbc2bd2d57443f6e6d01976553 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 19 Jun 2021 17:58:04 +0200
Subject: [PATCH 2171/2348] fix lint

---
 test/document.test.js | 83 +++++++++++++++++++++----------------------
 1 file changed, 41 insertions(+), 42 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 86cd3560e48..949be5963f7 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10372,61 +10372,60 @@ describe('document', function() {
         const err2 = yield user.validate({ pathsToSkip: ['name'] }).then(() => null, err => err);
         assert.deepEqual(Object.keys(err2.errors), ['age']);
       });
+    });
 
-      it('support `pathsToSkip` option for `Document#validateSync()`', () => {
-        const User = getUserModel();
+    it('support `pathsToSkip` option for `Document#validateSync()`', () => {
+      const User = getUserModel();
 
-        const user = new User();
+      const user = new User();
+
+      const err1 = user.validateSync({ pathsToSkip: ['age'] });
+      assert.deepEqual(Object.keys(err1.errors), ['name']);
 
-        const err1 = user.validateSync({ pathsToSkip: ['age'] });
+      const err2 = user.validateSync({ pathsToSkip: ['name'] });
+      assert.deepEqual(Object.keys(err2.errors), ['age']);
+    });
+
+    // skip until gh-10367 is implemented
+    xit('support `pathsToSkip` option for `Model.validate()`', () => {
+      return co(function*() {
+        const User = getUserModel();
+        const err1 = yield User.validate({}, { pathsToSkip: ['age'] });
         assert.deepEqual(Object.keys(err1.errors), ['name']);
 
-        const err2 = user.validateSync({ pathsToSkip: ['name'] });
+        const err2 = yield User.validate({}, { pathsToSkip: ['name'] });
         assert.deepEqual(Object.keys(err2.errors), ['age']);
       });
+    });
 
-      // skip until gh-10367 is implemented
-      xit('support `pathsToSkip` option for `Model.validate()`', () => {
-        return co(function*() {
-          const User = getUserModel();
-          const err1 = yield User.validate({}, { pathsToSkip: ['age'] });
-          assert.deepEqual(Object.keys(err1.errors), ['name']);
-
-          const err2 = yield User.validate({}, { pathsToSkip: ['name'] });
-          assert.deepEqual(Object.keys(err2.errors), ['age']);
-        });
+    it('`pathsToSkip` accepts space separated paths', () => {
+      const userSchema = Schema({
+        name: { type: String, required: true },
+        age: { type: Number, required: true },
+        country: { type: String, required: true },
+        rank: { type: String, required: true }
       });
 
-      it('`pathsToSkip` accepts space separated paths', () => {
-        const userSchema = Schema({
-          name: { type: String, required: true },
-          age: { type: Number, required: true },
-          country: { type: String, required: true },
-          rank: { type: String, required: true }
-        });
-
-        const User = db.model('User', userSchema);
-        return co(function* () {
-          const user = new User({ name: 'Sam', age: 26 });
+      const User = db.model('User', userSchema);
+      return co(function* () {
+        const user = new User({ name: 'Sam', age: 26 });
 
-          const err1 = user.validateSync({ pathsToSkip: 'country rank' });
-          assert.ok(err1 == null);
+        const err1 = user.validateSync({ pathsToSkip: 'country rank' });
+        assert.ok(err1 == null);
 
-          const err2 = yield user.validate({ pathsToSkip: 'country rank' }).then(() => null, err => err);
-          assert.ok(err2 == null);
-        });
+        const err2 = yield user.validate({ pathsToSkip: 'country rank' }).then(() => null, err => err);
+        assert.ok(err2 == null);
       });
-
-      function getUserModel() {
-        const userSchema = Schema({
-          name: { type: String, required: true },
-          age: { type: Number, required: true },
-          rank: String
-        });
-
-        const User = db.model('User', userSchema);
-        return User;
-      }
     });
+
+    function getUserModel() {
+      const userSchema = Schema({
+        name: { type: String, required: true },
+        age: { type: Number, required: true },
+        rank: String
+      });
+      const User = db.model('User', userSchema);
+      return User;
+    }
   });
 });

From c07046cadd94bec5584c8e6d7f4fe17219a50df7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 21 Jun 2021 19:54:24 +0200
Subject: [PATCH 2172/2348] perf(document): split pathsToSkip only if there's
 more than one path

---
 lib/document.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index 79112978325..9d3077c7e61 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -2252,7 +2252,8 @@ Document.prototype.validate = function(pathsToValidate, options, callback) {
     pathsToValidate = null;
   }
   if (options && typeof options.pathsToSkip === 'string') {
-    options.pathsToSkip = options.pathsToSkip.split(' ');
+    const isOnePathOnly = options.pathsToSkip.indexOf(' ') === -1;
+    options.pathsToSkip = isOnePathOnly ? [options.pathsToSkip] : options.pathsToSkip.split(' ');
   }
 
   return promiseOrCallback(callback, cb => {
@@ -2649,11 +2650,12 @@ Document.prototype.validateSync = function(pathsToValidate, options) {
     shouldValidateModifiedOnly = this.$__schema.options.validateModifiedOnly;
   }
 
-  let pathsToSkip = get(options, 'pathsToSkip');
+  let pathsToSkip = options && options.pathsToSkip;
 
   if (typeof pathsToValidate === 'string') {
-    pathsToValidate = pathsToValidate.split(' ');
-  } else if (typeof pathsToSkip === 'string') {
+    const isOnePathOnly = pathsToValidate.indexOf(' ') === -1;
+    pathsToValidate = isOnePathOnly ? [pathsToValidate] : pathsToValidate.split(' ');
+  } else if (typeof pathsToSkip === 'string' && pathsToSkip.indexOf(' ') !== -1) {
     pathsToSkip = pathsToSkip.split(' ');
   }
 

From f4d5ac2404111c014902870b22a690062cf8f94e Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Mon, 21 Jun 2021 20:03:42 +0200
Subject: [PATCH 2173/2348] fix merge linting issues

---
 test/document.test.js | 70 +++++++++++++++++++++----------------------
 1 file changed, 34 insertions(+), 36 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 9aaca518a0f..2d8b8f8552b 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10359,7 +10359,6 @@ describe('document', function() {
     assert.equal(obj.answer, null);
     assert.equal(obj.nested.hello, 'world');
   });
-
   describe('pathsToSkip (gh-10230)', () => {
     it('support `pathsToSkip` option for `Document#validate()`', function() {
       return co(function*() {
@@ -10373,44 +10372,18 @@ describe('document', function() {
         assert.deepEqual(Object.keys(err2.errors), ['age']);
       });
     });
-  });
-      
-  it('adds support for `pathsToSkip` for virtuals feat-10120', function() {
-    const schema = new mongoose.Schema({
-      name: String,
-      age: Number,
-      nested: {
-        test: String
-      }
-    });
-    schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
-    schema.virtual('answer').get(() => 42);
-    schema.virtual('nested.hello').get(() => 'world');
 
-    const Model = db.model('Person', schema);
-    const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
-    let obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
-    assert.ok(obj.nameUpper);
-    assert.equal(obj.answer, null);
-    assert.equal(obj.nested.hello, 'world');
-    obj = doc.toObject({ virtuals: { pathsToSkip: ['nested.hello'] } });
-    assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
-    assert.equal(obj.answer, 42);
-    assert.equal(obj.nested.hello, null);
+    it('support `pathsToSkip` option for `Document#validate()`', function() {
+      return co(function*() {
+        const User = getUserModel();
+        const user = new User();
 
-  });
+        const err1 = yield user.validate({ pathsToSkip: ['age'] }).then(() => null, err => err);
+        assert.deepEqual(Object.keys(err1.errors), ['name']);
 
-  it('support `pathsToSkip` option for `validate()` (feat-10230)', function() {
-    const schema = Schema({
-      name: {
-        type: String,
-        required: true
-      },
-      age: {
-        type: Number,
-        required: true
-      },
-      rank: String
+        const err2 = yield user.validate({ pathsToSkip: ['name'] }).then(() => null, err => err);
+        assert.deepEqual(Object.keys(err2.errors), ['age']);
+      });
     });
 
     it('support `pathsToSkip` option for `Document#validateSync()`', () => {
@@ -10457,12 +10430,37 @@ describe('document', function() {
       });
     });
 
+    it('adds support for `pathsToSkip` for virtuals feat-10120', function() {
+      const schema = new mongoose.Schema({
+        name: String,
+        age: Number,
+        nested: {
+          test: String
+        }
+      });
+      schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
+      schema.virtual('answer').get(() => 42);
+      schema.virtual('nested.hello').get(() => 'world');
+
+      const Model = db.model('Person', schema);
+      const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
+      let obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
+      assert.ok(obj.nameUpper);
+      assert.equal(obj.answer, null);
+      assert.equal(obj.nested.hello, 'world');
+      obj = doc.toObject({ virtuals: { pathsToSkip: ['nested.hello'] } });
+      assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+      assert.equal(obj.answer, 42);
+      assert.equal(obj.nested.hello, null);
+    });
+
     function getUserModel() {
       const userSchema = Schema({
         name: { type: String, required: true },
         age: { type: Number, required: true },
         rank: String
       });
+
       const User = db.model('User', userSchema);
       return User;
     }

From 6904cdeb83e936ea4e8d370496d1667d0b747594 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 21 Jun 2021 20:50:45 -0400
Subject: [PATCH 2174/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 7a39be7cf4a..4f60912c578 100644
--- a/index.pug
+++ b/index.pug
@@ -349,6 +349,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.slotbar888.com/">
                 <img class="sponsor" src="https://images.opencollective.com/slotbar/2843cec/avatar/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://writersperhour.com/write-my-paper">
+                <img class="sponsor" src="https://images.opencollective.com/write-my-paper/5787d4b/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 9fb05e21b2aebf08ea4dbfab7d952d84c83f6ee5 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 22 Jun 2021 12:36:18 +0200
Subject: [PATCH 2175/2348] test: separate virtuals pathsToSkip from validation
 pathsToSkip test cases

---
 test/document.test.js | 108 ++++++++++++++++++++++--------------------
 1 file changed, 56 insertions(+), 52 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 2d8b8f8552b..48135a4ac2c 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10323,43 +10323,69 @@ describe('document', function() {
     });
   });
 
-  it('supports passing a list of virtuals to `toObject()` (gh-10120)', function() {
-    const schema = new mongoose.Schema({
-      name: String,
-      age: Number,
-      nested: {
-        test: String
-      }
+  describe('virtuals `pathsToSkip` (gh-10120)', () => {
+    it('adds support for `pathsToSkip` for virtuals feat-10120', function() {
+      const schema = new mongoose.Schema({
+        name: String,
+        age: Number,
+        nested: {
+          test: String
+        }
+      });
+      schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
+      schema.virtual('answer').get(() => 42);
+      schema.virtual('nested.hello').get(() => 'world');
+
+      const Model = db.model('Person', schema);
+      const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
+      let obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
+      assert.ok(obj.nameUpper);
+      assert.equal(obj.answer, null);
+      assert.equal(obj.nested.hello, 'world');
+      obj = doc.toObject({ virtuals: { pathsToSkip: ['nested.hello'] } });
+      assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+      assert.equal(obj.answer, 42);
+      assert.equal(obj.nested.hello, null);
     });
-    schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
-    schema.virtual('answer').get(() => 42);
-    schema.virtual('nested.hello').get(() => 'world');
 
-    const Model = db.model('Person', schema);
+    it('supports passing a list of virtuals to `toObject()` (gh-10120)', function() {
+      const schema = new mongoose.Schema({
+        name: String,
+        age: Number,
+        nested: {
+          test: String
+        }
+      });
+      schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
+      schema.virtual('answer').get(() => 42);
+      schema.virtual('nested.hello').get(() => 'world');
 
-    const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
+      const Model = db.model('Person', schema);
 
-    let obj = doc.toObject({ virtuals: true });
-    assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
-    assert.equal(obj.answer, 42);
-    assert.equal(obj.nested.hello, 'world');
+      const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
 
-    obj = doc.toObject({ virtuals: ['answer'] });
-    assert.ok(!obj.nameUpper);
-    assert.equal(obj.answer, 42);
-    assert.equal(obj.nested.hello, null);
+      let obj = doc.toObject({ virtuals: true });
+      assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+      assert.equal(obj.answer, 42);
+      assert.equal(obj.nested.hello, 'world');
+
+      obj = doc.toObject({ virtuals: ['answer'] });
+      assert.ok(!obj.nameUpper);
+      assert.equal(obj.answer, 42);
+      assert.equal(obj.nested.hello, null);
 
-    obj = doc.toObject({ virtuals: ['nameUpper'] });
-    assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
-    assert.equal(obj.answer, null);
-    assert.equal(obj.nested.hello, null);
+      obj = doc.toObject({ virtuals: ['nameUpper'] });
+      assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
+      assert.equal(obj.answer, null);
+      assert.equal(obj.nested.hello, null);
 
-    obj = doc.toObject({ virtuals: ['nested.hello'] });
-    assert.equal(obj.nameUpper, null);
-    assert.equal(obj.answer, null);
-    assert.equal(obj.nested.hello, 'world');
+      obj = doc.toObject({ virtuals: ['nested.hello'] });
+      assert.equal(obj.nameUpper, null);
+      assert.equal(obj.answer, null);
+      assert.equal(obj.nested.hello, 'world');
+    });
   });
-  describe('pathsToSkip (gh-10230)', () => {
+  describe('validation `pathsToSkip` (gh-10230)', () => {
     it('support `pathsToSkip` option for `Document#validate()`', function() {
       return co(function*() {
         const User = getUserModel();
@@ -10430,29 +10456,6 @@ describe('document', function() {
       });
     });
 
-    it('adds support for `pathsToSkip` for virtuals feat-10120', function() {
-      const schema = new mongoose.Schema({
-        name: String,
-        age: Number,
-        nested: {
-          test: String
-        }
-      });
-      schema.virtual('nameUpper').get(function() { return this.name.toUpperCase(); });
-      schema.virtual('answer').get(() => 42);
-      schema.virtual('nested.hello').get(() => 'world');
-
-      const Model = db.model('Person', schema);
-      const doc = new Model({ name: 'Jean-Luc Picard', age: 59, nested: { test: 'hello' } });
-      let obj = doc.toObject({ virtuals: { pathsToSkip: ['answer'] } });
-      assert.ok(obj.nameUpper);
-      assert.equal(obj.answer, null);
-      assert.equal(obj.nested.hello, 'world');
-      obj = doc.toObject({ virtuals: { pathsToSkip: ['nested.hello'] } });
-      assert.equal(obj.nameUpper, 'JEAN-LUC PICARD');
-      assert.equal(obj.answer, 42);
-      assert.equal(obj.nested.hello, null);
-    });
 
     function getUserModel() {
       const userSchema = Schema({
@@ -10465,4 +10468,5 @@ describe('document', function() {
       return User;
     }
   });
+
 });

From f9efb03d57909efef08ddbfec71fb8e0e7936c5a Mon Sep 17 00:00:00 2001
From: LK HO <lkho@users.noreply.github.com>
Date: Wed, 23 Jun 2021 16:41:19 +0800
Subject: [PATCH 2176/2348] fix(TypeScript): Query.cast()

Query.cast() args should be optional
---
 index.d.ts | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index c3a5169105f..113944bb474 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1975,7 +1975,14 @@ declare module 'mongoose' {
     box(val: any): this;
     box(lower: number[], upper: number[]): this;
 
-    cast(model: Model<any, THelpers> | null, obj: any): UpdateQuery<DocType>;
+    /**
+     * Casts this query to the schema of `model`.
+     *
+     * @param {Model} [model] the model to cast to. If not set, defaults to `this.model`
+     * @param {Object} [obj] If not set, defaults to this query's conditions
+     * @return {Object} the casted `obj`
+     */
+    cast(model?: Model<any, THelpers> | null, obj?: any): any;
 
     /**
      * Executes the query returning a `Promise` which will be

From 9724173efa1f88c4a41229be2733f789ce3d693f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 23 Jun 2021 12:34:37 -0400
Subject: [PATCH 2177/2348] chore: create api dir to avoid unnecessary errors
 when running docs build

---
 website.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/website.js b/website.js
index 568d60de4ca..16d5ba30c85 100644
--- a/website.js
+++ b/website.js
@@ -68,6 +68,11 @@ pkg.version = getVersion();
 pkg.latest4x = getLatestLegacyVersion('4.');
 pkg.latest38x = getLatestLegacyVersion('3.8');
 
+// Create api dir if it doesn't already exist
+try {
+  fs.mkdirSync('./docs/api');
+} catch (err) {}
+
 require('./docs/splitApiDocs');
 const filemap = Object.assign({}, require('./docs/source'), require('./docs/tutorials'), require('./docs/typescript'));
 const files = Object.keys(filemap);

From 8f3207c45dd9a6c5680dcc4c1d4111bb54fa33b6 Mon Sep 17 00:00:00 2001
From: Daniel Diaz <39510674+IslandRhythms@users.noreply.github.com>
Date: Wed, 23 Jun 2021 14:06:44 -0400
Subject: [PATCH 2178/2348] fixed omission of discriminatorKey in options in
 docs

---
 lib/schema.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/schema.js b/lib/schema.js
index d48fee71719..55df5c399d5 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -53,6 +53,7 @@ let id = 0;
  * - [bufferTimeoutMS](/docs/guide.html#bufferTimeoutMS): number - defaults to 10000 (10 seconds). If `bufferCommands` is enabled, the amount of time Mongoose will wait for connectivity to be restablished before erroring out.
  * - [capped](/docs/guide.html#capped): bool - defaults to false
  * - [collection](/docs/guide.html#collection): string - no default
+ * - [discriminatorKey](/docs/guide.html#discriminatorKey): string - defaults to `__t`
  * - [id](/docs/guide.html#id): bool - defaults to true
  * - [_id](/docs/guide.html#_id): bool - defaults to true
  * - [minimize](/docs/guide.html#minimize): bool - controls [document#toObject](#document_Document-toObject) behavior when called manually - defaults to true

From 08f9b61a8f17dc905fae30a20c43adf8488fdaa3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 25 Jun 2021 14:30:15 -0400
Subject: [PATCH 2179/2348] style: fix lint

---
 website.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/website.js b/website.js
index 16d5ba30c85..1df3e091f34 100644
--- a/website.js
+++ b/website.js
@@ -71,7 +71,7 @@ pkg.latest38x = getLatestLegacyVersion('3.8');
 // Create api dir if it doesn't already exist
 try {
   fs.mkdirSync('./docs/api');
-} catch (err) {}
+} catch (err) {} // eslint-disable-line no-empty
 
 require('./docs/splitApiDocs');
 const filemap = Object.assign({}, require('./docs/source'), require('./docs/tutorials'), require('./docs/typescript'));

From 012808cd356ed542828bc8f39776b8dca496bf5d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 25 Jun 2021 14:56:00 -0400
Subject: [PATCH 2180/2348] chore: release 5.12.15

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index e6dca33d45d..9ff9034fbcc 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.12.15 / 2021-06-25
+====================
+ * fix(index.d.ts): add extra TInstanceMethods generic param to `Schema` for cases when we can't infer from Model #10358
+ * fix(index.d.ts): added typings for near() in model aggregation #10373 [tbhaxor](https://github.com/tbhaxor)
+ * fix(index.d.ts): correct function signature for `Query#cast()` #10388 [lkho](https://github.com/lkho)
+ * docs(transactions): add import statement #10365 [JimLynchCodes](https://github.com/JimLynchCodes)
+ * docs(schema): add missing `discriminatorKey` schema option #10386 #10376 [IslandRhythms](https://github.com/IslandRhythms)
+ * docs(index.d.ts): fix typo #10363 [houssemchebeb](https://github.com/houssemchebeb)
+
 5.12.14 / 2021-06-15
 ====================
  * fix(schema): check that schema type is an object when setting isUnderneathDocArray #10361 [vmo-khanus](https://github.com/vmo-khanus)
diff --git a/package.json b/package.json
index 8c0dd536f22..d5314d55de5 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.14",
+  "version": "5.12.15",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 1111f2f24cbc043e2375a92f5f8b5dbd5eac8c7a Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Sat, 26 Jun 2021 11:08:42 +1000
Subject: [PATCH 2181/2348] Upgrade CI environment to Ubuntu 20.04

Also refactor connection tests to remove use of mongodb-topology-manager
---
 .github/workflows/test.yml | 10 ++---
 package.json               |  3 +-
 test/common.js             | 17 --------
 test/connection.test.js    | 17 +++++++-
 test/connection_server.js  | 79 ++++++++++++++++++++++++++++++++++++++
 5 files changed, 102 insertions(+), 24 deletions(-)
 create mode 100644 test/connection_server.js

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 9c1b78b454e..01d1945cf2d 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -4,7 +4,7 @@ on:
     push:
 jobs:
   test:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
     strategy:
       fail-fast: false
       matrix:
@@ -26,16 +26,16 @@ jobs:
 
       - name: Setup
         run: |
-          wget -q http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1804-4.0.2.tgz
-          tar xf mongodb-linux-x86_64-ubuntu1804-4.0.2.tgz
+          wget -q https://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu2004-4.4.6.tgz
+          tar xf mongodb-linux-x86_64-ubuntu2004-4.4.6.tgz
           mkdir -p ./data/db/27017 ./data/db/27000
           printf "\n--timeout 8000" >> ./test/mocha.opts
-          ./mongodb-linux-x86_64-ubuntu1804-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+          ./mongodb-linux-x86_64-ubuntu2004-4.4.6/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
           sleep 2
           mongod --version
           mkdir ./test/typescript/node_modules
           ln -s `pwd` ./test/typescript/node_modules/mongoose
-          echo `pwd`/mongodb-linux-x86_64-ubuntu1804-4.0.2/bin >> $GITHUB_PATH
+          echo `pwd`/mongodb-linux-x86_64-ubuntu2004-4.4.6/bin >> $GITHUB_PATH
 
       - run: npm test
 
diff --git a/package.json b/package.json
index d5314d55de5..b441ee2be73 100644
--- a/package.json
+++ b/package.json
@@ -53,14 +53,15 @@
     "lodash.isequal": "4.5.0",
     "lodash.isequalwith": "4.4.0",
     "marked": "1.1.1",
+    "mkdirp": "0.5.5",
     "mocha": "5.x",
     "moment": "2.x",
-    "mongodb-topology-manager": "1.0.11",
     "mongoose-long": "0.2.1",
     "node-static": "0.7.11",
     "object-sizeof": "1.3.0",
     "pug": "2.0.3",
     "q": "1.5.1",
+    "rimraf": "2.6.3",
     "semver": "5.5.0",
     "typescript": "4.1.x",
     "uuid": "2.0.3",
diff --git a/test/common.js b/test/common.js
index 80ffac4f9b9..62580bf66f1 100644
--- a/test/common.js
+++ b/test/common.js
@@ -4,12 +4,10 @@
  * Module dependencies.
  */
 
-const Server = require('mongodb-topology-manager').Server;
 const mongoose = require('../');
 const Collection = mongoose.Collection;
 const assert = require('assert');
 
-let server;
 const collectionNames = new Map();
 
 if (process.env.D === '1') {
@@ -192,15 +190,6 @@ function dropDBs(done) {
   });
 }
 
-before(function() {
-  return server.purge();
-});
-
-after(function() {
-  this.timeout(15000);
-
-  return server.stop();
-});
 
 before(function(done) {
   this.timeout(10 * 1000);
@@ -214,12 +203,6 @@ after(function(done) {
   setTimeout(() => done(), 250);
 });
 
-module.exports.server = server = new Server('mongod', {
-  bind_ip: '127.0.0.1',
-  port: 27000,
-  dbpath: './data/db/27000'
-});
-
 beforeEach(function() {
   if (this.currentTest) {
     global.CURRENT_TEST = this.currentTest.title;
diff --git a/test/connection.test.js b/test/connection.test.js
index e4119967df2..c0a28ffc078 100644
--- a/test/connection.test.js
+++ b/test/connection.test.js
@@ -11,13 +11,28 @@ const Q = require('q');
 const assert = require('assert');
 const co = require('co');
 const mongodb = require('mongodb');
-const server = require('./common').server;
+
+const Server = require('./connection_server');
+const server = new Server('mongod', {
+  bind_ip: '127.0.0.1',
+  port: 27000,
+  dbpath: './data/db/27000'
+});
 
 const mongoose = start.mongoose;
 const Schema = mongoose.Schema;
 
 const uri = 'mongodb://localhost:27017/mongoose_test';
 
+before(function() {
+  return server.purge();
+});
+
+after(function() {
+  this.timeout(15000);
+  return server.stop();
+});
+
 /**
  * Test.
  */
diff --git a/test/connection_server.js b/test/connection_server.js
new file mode 100644
index 00000000000..ba535cb9950
--- /dev/null
+++ b/test/connection_server.js
@@ -0,0 +1,79 @@
+'use strict';
+const child_process = require('child_process');
+const mkdirp = require('mkdirp');
+const rimraf = require('rimraf');
+
+// For starting/stopping mongod to test connections
+// Adapted from mongodb-topology-manager:
+// https://github.com/mongodb-js/mongodb-topology-manager/blob/master/lib/server.js
+class Server {
+  constructor(binary, options) {
+    this.binary = binary;
+    this.port = options['port'] || 27017;
+    this.bind_ip = options['bind_ip'] || '127.0.0.1';
+    this.dbpath = options['dbpath'] || './data';
+  }
+
+  // Start server
+  start() {
+    const self = this;
+    return new Promise(function(resolve, reject) {
+      self.purge().then(function() {
+        // Spawn server process
+        self.server = child_process.spawn(self.binary,
+          ['--port', self.port, '--bind_ip',
+            self.bind_ip, '--dbpath', self.dbpath]);
+
+        // Wait for ready
+        self.server.stdout.on('data', function(data) {
+          if (data.toString().includes('Waiting for connections')) {
+            self.server.stdout.removeAllListeners('data');
+            self.server.removeAllListeners('exit');
+            resolve();
+          }
+        });
+
+        // Error
+        self.server.on('exit', function(code) {
+          reject(code);
+        });
+      }).catch(function(err) {
+        reject(err);
+      });
+    });
+  }
+
+  // Stop server
+  stop() {
+    const self = this;
+    return new Promise(function(resolve) {
+      if (!self.server) {
+        resolve();
+      }
+      // Resolve on exit
+      self.server.on('exit', function(code) {
+        self.server.stdout.removeAllListeners('data');
+        self.server.removeAllListeners('exit');
+        self.server = null;
+        resolve(code);
+      });
+      // Kill
+      self.server.kill('SIGINT');
+    });
+  }
+
+  // Remove and recreate data directory
+  purge() {
+    const self = this;
+    return new Promise(function(resolve, reject) {
+      rimraf(self.dbpath, {}, function(err) {
+        if (err) reject(err);
+        mkdirp(self.dbpath, { recursive: true }, function(err) {
+          if (err) reject(err);
+          resolve();
+        });
+      });
+    });
+  }
+}
+module.exports = Server;

From abf3b43748dceebd1c925f9925425f71765bed18 Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <tkkisaki@gmail.com>
Date: Sun, 27 Jun 2021 12:01:02 -0300
Subject: [PATCH 2182/2348] fix(index.d.ts): proper placement of
 `mongoose.Date` JSDoc

---
 index.d.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 113944bb474..616c2984df1 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -12,8 +12,9 @@ declare module 'mongoose' {
     uninitialized = 99,
   }
 
-  /** The Mongoose Date [SchemaType](/docs/schematypes.html). */
   class NativeDate extends global.Date {}
+
+  /** The Mongoose Date [SchemaType](/docs/schematypes.html). */
   export type Date = Schema.Types.Date;
 
   /**

From 0496de9f66142906c9fd91a0be2fccbfb8c1de7f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 28 Jun 2021 10:58:33 -0400
Subject: [PATCH 2183/2348] chore: release 5.13.0

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9ff9034fbcc..afefd2a14e0 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.13.0 / 2021-06-28
+===================
+ * feat(query): add sanitizeProjection option to opt in to automatically sanitizing untrusted query projections #10243
+ * feat(model): add `bulkSave()` function that saves multiple docs in 1 `bulkWrite()` #9727 #9673 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(document): allow passing a list of virtuals or `pathsToSkip` to apply in `toObject()` and `toJSON()` #10120
+ * fix(model): make Model.validate use object under validation as context by default #10360 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(document): add support for pathsToSkip in validate and validateSync #10375 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * feat(model): add `diffIndexes()` function that calculates what indexes `syncIndexes()` will create/drop without actually executing any changes #10362 [IslandRhythms](https://github.com/IslandRhythms)
+ * feat(document): avoid using sessions that have ended, so you can use documents that were loaded in the session after calling `endSession()` #10306
+
 5.12.15 / 2021-06-25
 ====================
  * fix(index.d.ts): add extra TInstanceMethods generic param to `Schema` for cases when we can't infer from Model #10358
diff --git a/package.json b/package.json
index f667696968d..35b8b99b437 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.12.15",
+  "version": "5.13.0",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From abdc61733b6010877adde9a2eb090668473f9dd4 Mon Sep 17 00:00:00 2001
From: Grimmer <grimmer0125@gmail.com>
Date: Wed, 30 Jun 2021 15:42:10 +0800
Subject: [PATCH 2184/2348] Fix outdated url about unindexed upsert

---
 docs/tutorials/findoneandupdate.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/tutorials/findoneandupdate.md b/docs/tutorials/findoneandupdate.md
index 83ab21a9c36..48f997231fe 100644
--- a/docs/tutorials/findoneandupdate.md
+++ b/docs/tutorials/findoneandupdate.md
@@ -34,7 +34,7 @@ which has the same option.
 
 <h2 id="atomic-updates">Atomic Updates</h2>
 
-With the exception of an [unindexed upsert](https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/#upsert-and-unique-index), [`findOneAndUpdate()` is atomic](https://docs.mongodb.com/manual/core/write-operations-atomicity/#atomicity). That means you can assume the document doesn't change between when MongoDB finds the document and when it updates the document, _unless_ you're doing an [upsert](#upsert).
+With the exception of an [unindexed upsert](https://docs.mongodb.com/manual/reference/method/db.collection.findAndModify/#upsert-with-unique-index), [`findOneAndUpdate()` is atomic](https://docs.mongodb.com/manual/core/write-operations-atomicity/#atomicity). That means you can assume the document doesn't change between when MongoDB finds the document and when it updates the document, _unless_ you're doing an [upsert](#upsert).
 
 For example, if you're using `save()` to update a document, the document can change in MongoDB in between when you load the document using `findOne()` and when you save the document using `save()` as show below. For many use cases, the `save()` race condition is a non-issue. But you can work around it with `findOneAndUpdate()` (or [transactions](/docs/transactions.html)) if you need to.
 

From 74181e37daabf1a63753d7c182df155119e0e034 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 30 Jun 2021 11:25:53 -0400
Subject: [PATCH 2185/2348] chore: update opencollective sponsors

---
 index.pug    | 3 +++
 package.json | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/index.pug b/index.pug
index 4f60912c578..c552a705065 100644
--- a/index.pug
+++ b/index.pug
@@ -352,6 +352,9 @@ html(lang='en')
               <a rel="sponsored" href="https://writersperhour.com/write-my-paper">
                 <img class="sponsor" src="https://images.opencollective.com/write-my-paper/5787d4b/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://www.gambledex.com/">
+                <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/gambedex.png" style="height: 100px">
+              </a>
             </div>
           </div>
 
diff --git a/package.json b/package.json
index 35b8b99b437..1d9490c65b7 100644
--- a/package.json
+++ b/package.json
@@ -249,4 +249,4 @@
     "type": "opencollective",
     "url": "https://opencollective.com/mongoose"
   }
-}
\ No newline at end of file
+}

From 18c9b8b9e6aa5ccc8632cb85a43db30156cd30d5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Jul 2021 10:10:16 -0400
Subject: [PATCH 2186/2348] fix(index.d.ts): allow defining map of schemas in
 TypeScript

Fix #10389
---
 index.d.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 5e8d5992366..121a401c016 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1256,9 +1256,9 @@ declare module 'mongoose' {
     ? (SchemaDefinitionWithBuiltInClass<T> | SchemaTypeOptions<T>) :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
-    Schema<any, any> |
-    Schema<any, any>[] |
-    ReadonlyArray<Schema<any, any>> |
+    Schema<any, any, any, any> |
+    Schema<any, any, any, any>[] |
+    ReadonlyArray<Schema<any, any, any, any>> |
     SchemaTypeOptions<T extends undefined ? any : T>[] |
     ReadonlyArray<SchemaTypeOptions<T extends undefined ? any : T>> |
     Function[] |
@@ -1546,7 +1546,7 @@ declare module 'mongoose' {
 
     /** If set, specifies the type of this map's values. Mongoose will cast this map's values to the given type. */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    of?: Function | SchemaTypeOptions<any>;
+    of?: Function | SchemaDefinitionProperty<any>;
 
     /** If true, uses Mongoose's default `_id` settings. Only allowed for ObjectIds */
     auto?: boolean;

From 6993e1e2ccfb8fd090bc4b3c0268e67e8f6a041a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Jul 2021 15:23:39 -0400
Subject: [PATCH 2187/2348] fix(index.d.ts): allow using `& Document` in schema
 definition for required subdocument arrays

Fix #10370
---
 index.d.ts                |  2 +-
 test/typescript/schema.ts | 10 +++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 121a401c016..e91a395413e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1438,7 +1438,7 @@ declare module 'mongoose' {
     type?:
       T extends string | number | boolean | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema<any, any> ? T :
-      T extends object[] ? (Schema<Document<Unpacked<T>>>[] | ReadonlyArray<Schema<Document<Unpacked<T>>>>) :
+      T extends object[] ? (Schema<Document<Unpacked<T>>>[] | ReadonlyArray<Schema<Document<Unpacked<T>>>> | Schema<Document & Unpacked<T>>[] | ReadonlyArray<Schema<Document & Unpacked<T>>>) :
       T extends string[] ? (SchemaDefinitionWithBuiltInClass<string>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<string>>) :
       T extends number[] ? (SchemaDefinitionWithBuiltInClass<number>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<number>>) :
       T extends boolean[] ? (SchemaDefinitionWithBuiltInClass<boolean>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<boolean>>) :
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 9ee1cc733cf..cd5711989b8 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -20,7 +20,7 @@ interface Movie {
   genre?: string,
   actionIntensity?: number,
   status?: string,
-  actors?: Actor[]
+  actors: Actor[]
 }
 
 const movieSchema = new Schema<Document<Movie>, Model<Document<Movie>>, Movie>({
@@ -147,3 +147,11 @@ function gh10287() {
     }
   });
 }
+
+function gh10370() {
+  const movieSchema = new Schema<Document & Movie, Model<Document & Movie>, Movie>({
+    actors: {
+      type: [actorSchema]
+    }
+  });
+}
\ No newline at end of file

From b236915c6b09ec46761479bfa3d8d05fdedcb360 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Jul 2021 16:28:03 -0400
Subject: [PATCH 2188/2348] test(model): repro #10303

---
 test/model.discriminator.test.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/test/model.discriminator.test.js b/test/model.discriminator.test.js
index 18ea0f91317..7cba3e97551 100644
--- a/test/model.discriminator.test.js
+++ b/test/model.discriminator.test.js
@@ -1776,4 +1776,24 @@ describe('model', function() {
     assert.ok(err);
     assert.ok(err.errors['name.firstName']);
   });
+
+  it('allows using array as tied value (gh-10303)', function() {
+    const mongooseSchema = new mongoose.Schema({
+      tenantRefs: [{
+        type: String,
+        required: true
+      }],
+      otherData: {
+        type: String,
+        required: true
+      }
+    }, { discriminatorKey: 'tenantRefs' });
+    const Model = db.model('Test', mongooseSchema);
+
+    const D = Model.discriminator('D', Schema({}), ['abc', '123']);
+
+    return D.create({ otherData: 'test', tenantRefs: ['abc', '123'] }).then(res => {
+      assert.deepEqual(res.toObject().tenantRefs, ['abc', '123']);
+    });
+  });
 });

From 35d204154fcc1c08cf084dfbc1bbdb8f21fa67bb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Jul 2021 16:28:19 -0400
Subject: [PATCH 2189/2348] fix(discriminator): allow using array as
 discriminator key in schema and as tied value

Fix #10303
---
 lib/helpers/model/discriminator.js | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/lib/helpers/model/discriminator.js b/lib/helpers/model/discriminator.js
index 455d17de2f9..24a569ed298 100644
--- a/lib/helpers/model/discriminator.js
+++ b/lib/helpers/model/discriminator.js
@@ -1,7 +1,6 @@
 'use strict';
 
 const Mixed = require('../../schema/mixed');
-const ObjectId = require('../../types/objectid');
 const defineKey = require('../document/compile').defineKey;
 const get = require('../get');
 const utils = require('../../utils');
@@ -64,9 +63,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
   }
 
   let value = name;
-  if ((typeof tiedValue === 'string' && tiedValue.length) ||
-      typeof tiedValue === 'number' ||
-      tiedValue instanceof ObjectId) {
+  if ((typeof tiedValue === 'string' && tiedValue.length) || tiedValue != null) {
     value = tiedValue;
   }
 
@@ -129,17 +126,17 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
       default: value,
       select: true,
       set: function(newName) {
-        if (newName === value) {
+        if (newName === value || (Array.isArray(value) && utils.deepEqual(newName, value))) {
           return value;
         }
         throw new Error('Can\'t set discriminator key "' + key + '"');
       },
       $skipDiscriminatorCheck: true
     };
-    obj[key][schema.options.typeKey] = existingPath ?
-      existingPath.instance :
-      String;
+    obj[key][schema.options.typeKey] = existingPath ? existingPath.options[schema.options.typeKey] : String;
     schema.add(obj);
+
+
     schema.discriminatorMapping = { key: key, value: value, isRoot: false };
 
     if (baseSchema.options.collection) {

From e4ab2dbd45088749e2edc18c1f808229bae0c61e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Jul 2021 17:40:46 -0400
Subject: [PATCH 2190/2348] fix(index.d.ts): correct return type for
 `Model.createCollection()`

Fix #10359
---
 index.d.ts                |  4 ++--
 test/typescript/models.ts | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e91a395413e..af9410ba633 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -679,8 +679,8 @@ declare module 'mongoose' {
      * mongoose will not create the collection for the model until any documents are
      * created. Use this method to create the collection explicitly.
      */
-    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<EnforceDocument<T, TMethods>>>;
-    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<EnforceDocument<T, TMethods>>) => void): void;
+    createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
+    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<T>) => void): void;
 
     /**
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
diff --git a/test/typescript/models.ts b/test/typescript/models.ts
index b522d619470..d8b37b5dc4e 100644
--- a/test/typescript/models.ts
+++ b/test/typescript/models.ts
@@ -121,6 +121,25 @@ function gh10074() {
   });
 }
 
+async function gh10359() {
+  interface Group {
+    groupId: string;
+  }
+
+  interface User extends Group {
+    firstName: string;
+    lastName: string;
+  }
+
+  async function foo<T extends Group>(model: Model<any>): Promise<T | null> {
+    const doc: T | null = await model.findOne({ groupId: 'test' }).lean().exec();
+    return doc;
+  }
+
+  const UserModel = model<User>('gh10359', new Schema({ firstName: String, lastName: String, groupId: String }));
+  const u: User | null = await foo<User>(UserModel);
+}
+
 const ExpiresSchema = new Schema({
   ttl: {
     type: Date,

From 8fbe0c7f2b2cccf97e9c51b71f1f0a4cfc7247b8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 1 Jul 2021 18:16:06 -0400
Subject: [PATCH 2191/2348] docs(promises+discriminators): correctly escape ()
 in regexp to pull in examples correctly

Fix #10364
---
 docs/discriminators.md | 2 +-
 docs/promises.md       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/discriminators.md b/docs/discriminators.md
index 3033a5d1276..670fd78118b 100644
--- a/docs/discriminators.md
+++ b/docs/discriminators.md
@@ -15,7 +15,7 @@ key (defaults to the model name). It returns a model whose schema
 is the union of the base schema and the discriminator schema.
 
 ```javascript
-[require:The `model.discriminator()` function]
+[require:The `model.discriminator\(\)` function]
 ```
 
 ### Discriminators save to the Event model's collection
diff --git a/docs/promises.md b/docs/promises.md
index ed426cf5175..562626890a3 100644
--- a/docs/promises.md
+++ b/docs/promises.md
@@ -47,7 +47,7 @@ However, we recommend using `.exec()` because that gives you
 better stack traces.
 
 ```javascript
-[require:Should You Use `exec()` With `await`]
+[require:Should You Use `exec\(\)` With `await`]
 ```
 
 ### Plugging in your own Promises Library

From d859617718dab8be577659db9fb9181a6e7b7107 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Fri, 2 Jul 2021 13:17:51 +1000
Subject: [PATCH 2192/2348] revert test.yml

---
 .github/workflows/test.yml | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 01d1945cf2d..9c1b78b454e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -4,7 +4,7 @@ on:
     push:
 jobs:
   test:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-18.04
     strategy:
       fail-fast: false
       matrix:
@@ -26,16 +26,16 @@ jobs:
 
       - name: Setup
         run: |
-          wget -q https://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu2004-4.4.6.tgz
-          tar xf mongodb-linux-x86_64-ubuntu2004-4.4.6.tgz
+          wget -q http://downloads.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1804-4.0.2.tgz
+          tar xf mongodb-linux-x86_64-ubuntu1804-4.0.2.tgz
           mkdir -p ./data/db/27017 ./data/db/27000
           printf "\n--timeout 8000" >> ./test/mocha.opts
-          ./mongodb-linux-x86_64-ubuntu2004-4.4.6/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
+          ./mongodb-linux-x86_64-ubuntu1804-4.0.2/bin/mongod --fork --dbpath ./data/db/27017 --syslog --port 27017
           sleep 2
           mongod --version
           mkdir ./test/typescript/node_modules
           ln -s `pwd` ./test/typescript/node_modules/mongoose
-          echo `pwd`/mongodb-linux-x86_64-ubuntu2004-4.4.6/bin >> $GITHUB_PATH
+          echo `pwd`/mongodb-linux-x86_64-ubuntu1804-4.0.2/bin >> $GITHUB_PATH
 
       - run: npm test
 

From de5632e29c9ffdba63bbd8798c883176a95817f4 Mon Sep 17 00:00:00 2001
From: Steven Tang <steven@steventang.net>
Date: Fri, 2 Jul 2021 14:24:42 +1000
Subject: [PATCH 2193/2348] fix: support for mongod < 4.4.0

---
 test/connection_server.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/test/connection_server.js b/test/connection_server.js
index ba535cb9950..b2e67ad59a6 100644
--- a/test/connection_server.js
+++ b/test/connection_server.js
@@ -26,7 +26,8 @@ class Server {
 
         // Wait for ready
         self.server.stdout.on('data', function(data) {
-          if (data.toString().includes('Waiting for connections')) {
+          if (data.toString().includes('Waiting for connections')
+              || data.toString().includes('waiting for connections')) {
             self.server.stdout.removeAllListeners('data');
             self.server.removeAllListeners('exit');
             resolve();

From 01c25ee32008f99726d7f516d17e5eb5933df52f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 10:55:43 -0400
Subject: [PATCH 2194/2348] fix(index.d.ts): if using DocType that doesn't
 `extends Document`, default to returning that DocType from `toObject()` and
 `toJSON()`

Fix #10345
---
 index.d.ts                       |  8 ++++----
 test/typescript/leanDocuments.ts | 31 ++++++++++++++++++++++++++++++-
 test/typescript/main.test.js     |  3 ++-
 3 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index af9410ba633..787b957f690 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -367,7 +367,7 @@ declare module 'mongoose' {
     getIndexes(): any;
   }
 
-  class Document<T = any, TQueryHelpers = any> {
+  class Document<T = any, TQueryHelpers = any, DocType = any> {
     constructor(doc?: any);
 
     /** This documents _id. */
@@ -583,11 +583,11 @@ declare module 'mongoose' {
 
     /** The return value of this method is used in calls to JSON.stringify(doc). */
     toJSON(options?: ToObjectOptions): LeanDocument<this>;
-    toJSON<T>(options?: ToObjectOptions): T;
+    toJSON<T = DocType>(options?: ToObjectOptions): T;
 
     /** Converts this document into a plain-old JavaScript object ([POJO](https://masteringjs.io/tutorials/fundamentals/pojo)). */
     toObject(options?: ToObjectOptions): LeanDocument<this>;
-    toObject<T>(options?: ToObjectOptions): T;
+    toObject<T = DocType>(options?: ToObjectOptions): T;
 
     /** Clears the modified state on the specified path. */
     unmarkModified(path: string): void;
@@ -622,7 +622,7 @@ declare module 'mongoose' {
   }
 
   interface AnyObject { [k: string]: any }
-  type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document & TMethods;
+  type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document<any, any, T> & TMethods;
 
   export const Model: Model<any>;
   // eslint-disable-next-line no-undef
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index 95a61a1c8b2..fa95b7843f4 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -48,4 +48,33 @@ void async function main() {
   _docs[0].mixed = 42;
 
   const _doc2: ITestBase = await Test.findOne().lean<ITestBase>();
-}();
\ No newline at end of file
+}();
+
+function gh10345() {
+  (function() {
+    interface User {
+      name: string;
+      id: number;
+    }
+
+    const UserModel = model<User>('User', new Schema({ name: String, id: Number }));
+
+    const doc = new UserModel({ name: 'test', id: 42 });
+
+    const leanDoc = doc.toObject();
+    leanDoc.id = 43;
+  })();
+
+  (function() {
+    interface User {
+      name: string;
+    }
+
+    const UserModel = model<User>('User', new Schema({ name: String }));
+
+    const doc = new UserModel({ name: 'test' });
+
+    const leanDoc = doc.toObject<User>();
+    leanDoc.id = 43;
+  })();
+}
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 513950f97df..3cb057866f5 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -118,10 +118,11 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 3);
+    assert.equal(errors.length, 4);
     assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
     assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[1].messageText);
     assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[2].messageText);
+    assert.ok(errors[3].messageText.includes('Property \'id\' does not exist'), errors[3].messageText);
   });
 
   it('doc array', function() {

From 5427f215f1d3834536207d6dedfc74ec26e17385 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 11:12:58 -0400
Subject: [PATCH 2195/2348] refactor(index.d.ts): dont enforce extends DocType
 for queries re: #10345

---
 index.d.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 787b957f690..e1ad48da280 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1948,9 +1948,9 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false } | {returnDocument: 'after'};
 
-  type QueryWithHelpers<ResultType, DocType extends Document, THelpers = {}> = Query<ResultType, DocType, THelpers> & THelpers;
+  type QueryWithHelpers<ResultType, DocType, THelpers = {}> = Query<ResultType, DocType, THelpers> & THelpers;
 
-  class Query<ResultType, DocType extends Document, THelpers = {}> {
+  class Query<ResultType, DocType, THelpers = {}> {
     _mongooseOptions: MongooseQueryOptions;
 
     /**
@@ -2459,7 +2459,7 @@ declare module 'mongoose' {
     T extends Document ? LeanDocument<T> :
     T;
 
-  class QueryCursor<DocType extends Document> extends stream.Readable {
+  class QueryCursor<DocType> extends stream.Readable {
     [Symbol.asyncIterator](): AsyncIterableIterator<DocType>;
 
     /**
@@ -2490,7 +2490,7 @@ declare module 'mongoose' {
      * Registers a transform function which subsequently maps documents retrieved
      * via the streams interface or `.next()`
      */
-    map<ResultType extends Document>(fn: (res: DocType) => ResultType): QueryCursor<ResultType>;
+    map<ResultType>(fn: (res: DocType) => ResultType): QueryCursor<ResultType>;
 
     /**
      * Get the next document from this cursor. Will return `null` when there are

From c8a0b53f886687f43f63ca4826491f51443fcfae Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 11:57:15 -0400
Subject: [PATCH 2196/2348] fix(index.d.ts): use raw DocType instead of
 `LeanDocument` when using `lean()` with queries if raw DocType doesn't
 `extends Document`

Fix #10345
---
 index.d.ts                       | 163 ++++++++++++++++---------------
 test/typescript/leanDocuments.ts |   5 +-
 test/typescript/main.test.js     |   3 +-
 3 files changed, 90 insertions(+), 81 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index e1ad48da280..29e67602a50 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -656,12 +656,12 @@ declare module 'mongoose' {
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a new document or documents */
     create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<EnforceDocument<T, TMethods>[]>;
@@ -697,18 +697,18 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
@@ -729,10 +729,10 @@ declare module 'mongoose' {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
@@ -802,7 +802,7 @@ declare module 'mongoose' {
 
     /** Adds a `$where` clause to this query */
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    $where(argument: string | Function): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Registered discriminators for this model. */
     discriminators: { [name: string]: Model<any> } | undefined;
@@ -811,10 +811,10 @@ declare module 'mongoose' {
     translateAliases(raw: any): any;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Returns true if at least one document exists in the database that matches
@@ -824,38 +824,38 @@ declare module 'mongoose' {
     exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    find(callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
-    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>>) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>>) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
@@ -863,11 +863,11 @@ declare module 'mongoose' {
       callback?: (err: any, res: any) => void
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -876,18 +876,18 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
-    where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    where(obj: object): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
-    where(): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers>;
+    where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    where(obj: object): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    where(): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
   }
 
   type _UpdateWriteOpResult = mongodb.UpdateWriteOpResult['result'];
@@ -1948,9 +1948,9 @@ declare module 'mongoose' {
 
   type ReturnsNewDoc = { new: true } | { returnOriginal: false } | {returnDocument: 'after'};
 
-  type QueryWithHelpers<ResultType, DocType, THelpers = {}> = Query<ResultType, DocType, THelpers> & THelpers;
+  type QueryWithHelpers<ResultType, DocType, THelpers = {}, RawDocType = DocType> = Query<ResultType, DocType, THelpers, RawDocType> & THelpers;
 
-  class Query<ResultType, DocType, THelpers = {}> {
+  class Query<ResultType, DocType, THelpers = {}, RawDocType = DocType> {
     _mongooseOptions: MongooseQueryOptions;
 
     /**
@@ -1967,7 +1967,7 @@ declare module 'mongoose' {
     exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
 
     // eslint-disable-next-line @typescript-eslint/ban-types
-    $where(argument: string | Function): QueryWithHelpers<DocType[], DocType, THelpers>;
+    $where(argument: string | Function): QueryWithHelpers<DocType[], DocType, THelpers, RawDocType>;
 
     /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     all(val: Array<any>): this;
@@ -2010,12 +2010,12 @@ declare module 'mongoose' {
     comment(val: string): this;
 
     /** Specifies this query as a `count` query. */
-    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
-    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
+    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /** Specifies this query as a `countDocuments` query. */
-    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
-    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
+    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /**
      * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
@@ -2028,21 +2028,21 @@ declare module 'mongoose' {
      * remove, except it deletes _every_ document that matches `filter` in the
      * collection, regardless of the value of `single`.
      */
-    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
-    deleteMany(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
-    deleteMany(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteMany(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteMany(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as a `deleteOne()` operation. Works like
      * remove, except it deletes at most one document regardless of the `single`
      * option.
      */
-    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
-    deleteOne(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
-    deleteOne(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteOne(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteOne(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers>;
+    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     // eslint-disable-next-line @typescript-eslint/ban-types
@@ -2061,7 +2061,7 @@ declare module 'mongoose' {
     equals(val: any): this;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
@@ -2076,31 +2076,31 @@ declare module 'mongoose' {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers>;
-    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers>;
+    find(callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
-    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
-    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers, RawDocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers, RawDocType>;
+    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers, RawDocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers, RawDocType>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$geometry` condition */
     geometry(object: { type: string, coordinates: any[] }): this;
@@ -2149,7 +2149,7 @@ declare module 'mongoose' {
     j(val: boolean | null): this;
 
     /** Sets the lean option. */
-    lean<LeanResultType = LeanDocumentOrArray<ResultType>>(val?: boolean | any): QueryWithHelpers<LeanResultType, DocType, THelpers>;
+    lean<LeanResultType = RawDocType extends Document ? LeanDocumentOrArray<ResultType> : LeanDocumentOrArrayWithRawType<ResultType, RawDocType>>(val?: boolean | any): QueryWithHelpers<LeanResultType, DocType, THelpers, RawDocType>;
 
     /** Specifies the maximum number of documents the query will return. */
     limit(val: number): this;
@@ -2166,7 +2166,7 @@ declare module 'mongoose' {
      * Runs a function `fn` and treats the return value of `fn` as the new value
      * for the query to resolve to.
      */
-    map<MappedType>(fn: (doc: DocType) => MappedType): QueryWithHelpers<ResultType extends unknown[] ? MappedType[] : MappedType, DocType, THelpers>;
+    map<MappedType>(fn: (doc: DocType) => MappedType): QueryWithHelpers<ResultType extends unknown[] ? MappedType[] : MappedType, DocType, THelpers, RawDocType>;
 
     /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     maxDistance(val: number): this;
@@ -2218,7 +2218,7 @@ declare module 'mongoose' {
      * This is handy for integrating with async/await, because `orFail()` saves you
      * an extra `if` statement to check if no document was found.
      */
-    orFail(err?: NativeError | (() => NativeError)): QueryWithHelpers<NonNullable<ResultType>, DocType, THelpers>;
+    orFail(err?: NativeError | (() => NativeError)): QueryWithHelpers<NonNullable<ResultType>, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$polygon` condition */
     polygon(...coordinatePairs: number[][]): this;
@@ -2246,15 +2246,15 @@ declare module 'mongoose' {
      * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
      * or [`deleteMany()`](#query_Query-deleteMany) instead.
      */
-    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): QueryWithHelpers<mongodb.WriteOpResult['result'], DocType, THelpers>;
+    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): QueryWithHelpers<mongodb.WriteOpResult['result'], DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as a replaceOne() operation. Same as
      * `update()`, except MongoDB will replace the existing document and will
      * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
      */
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;
@@ -2320,10 +2320,10 @@ declare module 'mongoose' {
     then: Promise<ResultType>['then'];
 
     /** Converts this query to a customized, reusable query constructor with all arguments and options retained. */
-    toConstructor(): new (...args: any[]) => QueryWithHelpers<ResultType, DocType, THelpers>;
+    toConstructor(): new (...args: any[]) => QueryWithHelpers<ResultType, DocType, THelpers, RawDocType>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -2331,13 +2331,13 @@ declare module 'mongoose' {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
@@ -2459,6 +2459,11 @@ declare module 'mongoose' {
     T extends Document ? LeanDocument<T> :
     T;
 
+  export type LeanDocumentOrArrayWithRawType<T, RawDocType> = 0 extends (1 & T) ? T :
+    T extends unknown[] ? RawDocType[] :
+    T extends Document ? RawDocType :
+    T;
+
   class QueryCursor<DocType> extends stream.Readable {
     [Symbol.asyncIterator](): AsyncIterableIterator<DocType>;
 
diff --git a/test/typescript/leanDocuments.ts b/test/typescript/leanDocuments.ts
index fa95b7843f4..25690030c0b 100644
--- a/test/typescript/leanDocuments.ts
+++ b/test/typescript/leanDocuments.ts
@@ -65,7 +65,7 @@ function gh10345() {
     leanDoc.id = 43;
   })();
 
-  (function() {
+  (async function() {
     interface User {
       name: string;
     }
@@ -76,5 +76,8 @@ function gh10345() {
 
     const leanDoc = doc.toObject<User>();
     leanDoc.id = 43;
+
+    const doc2 = await UserModel.findOne().orFail().lean();
+    doc2.id = 43;
   })();
 }
\ No newline at end of file
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 3cb057866f5..2af14034de4 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -118,11 +118,12 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 4);
+    assert.equal(errors.length, 5);
     assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
     assert.ok(errors[1].messageText.includes('Property \'save\' does not exist'), errors[1].messageText);
     assert.ok(errors[2].messageText.includes('Property \'testMethod\' does not exist'), errors[2].messageText);
     assert.ok(errors[3].messageText.includes('Property \'id\' does not exist'), errors[3].messageText);
+    assert.ok(errors[4].messageText.includes('Property \'id\' does not exist'), errors[4].messageText);
   });
 
   it('doc array', function() {

From 4d43d1b9752ad62d10ff403d90daf712f6fad0ad Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 12:59:56 -0400
Subject: [PATCH 2197/2348] fix(index.d.ts): remove `err: any` in callbacks,
 use `err: CallbackError` instead

Fix #10340
---
 index.d.ts | 134 ++++++++++++++++++++++++++---------------------------
 1 file changed, 67 insertions(+), 67 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 29e67602a50..0a5362befb6 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -136,7 +136,7 @@ declare module 'mongoose' {
    * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
    */
   export function startSession(options?: mongodb.SessionOptions): Promise<mongodb.ClientSession>;
-  export function startSession(options: mongodb.SessionOptions, cb: (err: any, session: mongodb.ClientSession) => void): void;
+  export function startSession(options: mongodb.SessionOptions, cb: (err: CallbackError, session: mongodb.ClientSession) => void): void;
 
   /** The Mongoose version */
   export const version: string;
@@ -304,7 +304,7 @@ declare module 'mongoose' {
      * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
      */
     startSession(options?: mongodb.SessionOptions): Promise<mongodb.ClientSession>;
-    startSession(options: mongodb.SessionOptions, cb: (err: any, session: mongodb.ClientSession) => void): void;
+    startSession(options: mongodb.SessionOptions, cb: (err: CallbackError, session: mongodb.ClientSession) => void): void;
 
     /**
      * _Requires MongoDB >= 3.6.0._ Executes the wrapped async function
@@ -554,7 +554,7 @@ declare module 'mongoose' {
      * [`execPopulate()`](#document_Document-execPopulate).
      */
     populate(path: string, callback?: (err: CallbackError, res: this) => void): this;
-    populate(path: string, names: string, callback?: (err: any, res: this) => void): this;
+    populate(path: string, names: string, callback?: (err: CallbackError, res: this) => void): this;
     populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: (err: CallbackError, res: this) => void): this;
 
     /** Gets _id(s) used during population of the given `path`. If the path was not populated, returns `undefined`. */
@@ -565,8 +565,8 @@ declare module 'mongoose' {
     remove(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
 
     /** Sends a replaceOne command with this document `_id` as the query selector. */
-    replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, this>;
-    replaceOne(replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): Query<any, this>;
+    replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
+    replaceOne(replacement?: Object, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
 
     /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
     save(options?: SaveOptions): Promise<this>;
@@ -650,18 +650,18 @@ declare module 'mongoose' {
      * trip to MongoDB.
      */
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions): Promise<mongodb.BulkWriteOpResultObject>;
-    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: any, res: mongodb.BulkWriteOpResultObject) => void): void;
+    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: CallbackError, res: mongodb.BulkWriteOpResultObject) => void): void;
 
     /** Collection the model uses. */
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    count(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    count(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    count(filter: FilterQuery<T>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    countDocuments(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    countDocuments(filter: FilterQuery<T>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a new document or documents */
     create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<EnforceDocument<T, TMethods>[]>;
@@ -686,8 +686,8 @@ declare module 'mongoose' {
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
      * function.
      */
-    createIndexes(callback?: (err: any) => void): Promise<void>;
-    createIndexes(options?: any, callback?: (err: any) => void): Promise<void>;
+    createIndexes(callback?: (err: CallbackError) => void): Promise<void>;
+    createIndexes(options?: any, callback?: (err: CallbackError) => void): Promise<void>;
 
     /** Connection the model uses. */
     db: Connection;
@@ -714,8 +714,8 @@ declare module 'mongoose' {
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
      */
-    ensureIndexes(callback?: (err: any) => void): Promise<void>;
-    ensureIndexes(options?: any, callback?: (err: any) => void): Promise<void>;
+    ensureIndexes(callback?: (err: CallbackError) => void): Promise<void>;
+    ensureIndexes(options?: any, callback?: (err: CallbackError) => void): Promise<void>;
 
     /**
      * Event emitter that reports any errors that occurred. Useful for global error
@@ -748,7 +748,7 @@ declare module 'mongoose' {
      * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
      * don't need to call it.
      */
-    init(callback?: (err: any) => void): Promise<EnforceDocument<T, TMethods>>;
+    init(callback?: (err: CallbackError) => void): Promise<EnforceDocument<T, TMethods>>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
@@ -772,9 +772,9 @@ declare module 'mongoose' {
 
     /** Populates document references. */
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: any, res: (EnforceDocument<T, TMethods>)[]) => void): Promise<Array<EnforceDocument<T, TMethods>>>;
+      callback?: (err: CallbackError, res: (EnforceDocument<T, TMethods>)[]) => void): Promise<Array<EnforceDocument<T, TMethods>>>;
     populate(doc: any, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: any, res: EnforceDocument<T, TMethods>) => void): Promise<EnforceDocument<T, TMethods>>;
+      callback?: (err: CallbackError, res: EnforceDocument<T, TMethods>) => void): Promise<EnforceDocument<T, TMethods>>;
 
     /**
      * Makes the indexes in MongoDB match the indexes defined in this model's
@@ -790,12 +790,12 @@ declare module 'mongoose' {
      * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
      * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
      * */
-    startSession(options?: mongodb.SessionOptions, cb?: (err: any, session: mongodb.ClientSession) => void): Promise<mongodb.ClientSession>;
+    startSession(options?: mongodb.SessionOptions, cb?: (err: CallbackError, session: mongodb.ClientSession) => void): Promise<mongodb.ClientSession>;
 
     /** Casts and validates the given object against this model's schema, passing the given `context` to custom validators. */
-    validate(callback?: (err: any) => void): Promise<void>;
-    validate(optional: any, callback?: (err: any) => void): Promise<void>;
-    validate(optional: any, pathsToValidate: string[], callback?: (err: any) => void): Promise<void>;
+    validate(callback?: (err: CallbackError) => void): Promise<void>;
+    validate(optional: any, callback?: (err: CallbackError) => void): Promise<void>;
+    validate(optional: any, pathsToValidate: string[], callback?: (err: CallbackError) => void): Promise<void>;
 
     /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
     watch(pipeline?: Array<Record<string, unknown>>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
@@ -811,63 +811,63 @@ declare module 'mongoose' {
     translateAliases(raw: any): any;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Returns true if at least one document exists in the database that matches
      * the given `filter`, and false otherwise.
      */
     exists(filter: FilterQuery<T>): Promise<boolean>;
-    exists(filter: FilterQuery<T>, callback: (err: any, res: boolean) => void): void;
+    exists(filter: FilterQuery<T>, callback: (err: CallbackError, res: boolean) => void): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    find(filter: FilterQuery<T>, callback?: (err: any, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: any, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(callback?: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(filter: FilterQuery<T>, callback?: (err: CallbackError, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findByIdAndRemove` query, filtering by the given `_id`. */
-    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndRemove(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, callback?: (err: any, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: CallbackError, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<T> | UpdateWithAggregationPipeline, callback?: (err: CallbackError, doc: T | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndDelete(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: CallbackError, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>>) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
       o: MapReduceOptions<T, Key, Value>,
-      callback?: (err: any, res: any) => void
+      callback?: (err: CallbackError, res: any) => void
     ): Promise<any>;
 
     remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -876,13 +876,13 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
@@ -1964,7 +1964,7 @@ declare module 'mongoose' {
     exec(): Promise<ResultType>;
     exec(callback?: (err: CallbackError, res: ResultType) => void): void;
     // @todo: this doesn't seem right
-    exec(callback?: (err: any, result: ResultType) => void): Promise<ResultType> | any;
+    exec(callback?: (err: CallbackError, result: ResultType) => void): Promise<ResultType> | any;
 
     // eslint-disable-next-line @typescript-eslint/ban-types
     $where(argument: string | Function): QueryWithHelpers<DocType[], DocType, THelpers, RawDocType>;
@@ -2010,12 +2010,12 @@ declare module 'mongoose' {
     comment(val: string): this;
 
     /** Specifies this query as a `count` query. */
-    count(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
-    count(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    count(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    count(criteria: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /** Specifies this query as a `countDocuments` query. */
-    countDocuments(callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
-    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    countDocuments(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /**
      * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
@@ -2042,7 +2042,7 @@ declare module 'mongoose' {
     deleteOne(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: any, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers, RawDocType>;
+    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     // eslint-disable-next-line @typescript-eslint/ban-types
@@ -2061,7 +2061,7 @@ declare module 'mongoose' {
     equals(val: any): this;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: any, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
@@ -2076,31 +2076,31 @@ declare module 'mongoose' {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
-    find(filter: FilterQuery<DocType>, callback?: (err: any, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(filter: FilterQuery<DocType>, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
     find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
     findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
-    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
+    findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndRemove` query: atomically finds the given document and deletes it. */
-    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
+    findOneAndRemove(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers, RawDocType>;
-    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers, RawDocType>;
-    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: CallbackError, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers, RawDocType>;
+    findOneAndUpdate(filter: FilterQuery<DocType>, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers, RawDocType>;
+    findOneAndUpdate(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
-    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
+    findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndUpdate` query, filtering by the given `_id`. */
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: any, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers, RawDocType>;
-    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: any, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers, RawDocType>;
-    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: any, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: CallbackError, doc: mongodb.FindAndModifyWriteOpResultObject<DocType>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<DocType>, DocType, THelpers, RawDocType>;
+    findByIdAndUpdate(id: mongodb.ObjectId | any, update: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: DocType, res: any) => void): QueryWithHelpers<DocType, DocType, THelpers, RawDocType>;
+    findByIdAndUpdate(id?: mongodb.ObjectId | any, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$geometry` condition */
     geometry(object: { type: string, coordinates: any[] }): this;
@@ -2253,8 +2253,8 @@ declare module 'mongoose' {
      * `update()`, except MongoDB will replace the existing document and will
      * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
      */
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: (err: any, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;
@@ -2544,7 +2544,7 @@ declare module 'mongoose' {
     cursor(options?: Record<string, unknown>): this;
 
     /** Executes the aggregate pipeline on the currently bound Model. If cursor option is set, returns a cursor */
-    exec(callback?: (err: any, result: R) => void): Promise<R> | any;
+    exec(callback?: (err: CallbackError, result: R) => void): Promise<R> | any;
 
     /** Execute the aggregation with explain */
     explain(callback?: (err: CallbackError, result: any) => void): Promise<any>;

From 5bbc8e05674e4994ad8b665398f4231e8b2cefa8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 13:54:57 -0400
Subject: [PATCH 2198/2348] chore: release 5.13.1

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index afefd2a14e0..b1f7042c287 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.13.1 / 2021-07-02
+===================
+ * fix(discriminator): allow using array as discriminator key in schema and as tied value #10303
+ * fix(index.d.ts): allow using & Document in schema definition for required subdocument arrays #10370
+ * fix(index.d.ts): if using DocType that doesn't extends Document, default to returning that DocType from `toObject()` and `toJSON()` #10345
+ * fix(index.d.ts): use raw DocType instead of LeanDocument when using `lean()` with queries if raw DocType doesn't `extends Document` #10345
+ * fix(index.d.ts): remove err: any in callbacks, use `err: CallbackError` instead #10340
+ * fix(index.d.ts): allow defining map of schemas in TypeScript #10389
+ * fix(index.d.ts): correct return type for Model.createCollection() #10359
+ * docs(promises+discriminators): correctly escape () in regexp to pull in examples correctly #10364
+ * docs(update): fix outdated URL about unindexed upsert #10406 [grimmer0125](https://github.com/grimmer0125)
+ * docs(index.d.ts): proper placement of mongoose.Date JSDoc [thiagokisaki](https://github.com/thiagokisaki)
+
 5.13.0 / 2021-06-28
 ===================
  * feat(query): add sanitizeProjection option to opt in to automatically sanitizing untrusted query projections #10243
diff --git a/package.json b/package.json
index 1147935af77..09210053d1e 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.0",
+  "version": "5.13.1",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 6661b001c0501b6bf348587610e84bb7237ed7f5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 14:48:40 -0400
Subject: [PATCH 2199/2348] docs(transactions): add note about creating a
 connection to transactions docs

Fix #10405
---
 docs/transactions.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/docs/transactions.md b/docs/transactions.md
index 016537eb9fe..9fe2d5129db 100644
--- a/docs/transactions.md
+++ b/docs/transactions.md
@@ -16,7 +16,12 @@ To create a transaction, you first need to create a session using or [`Mongoose#
 or [`Connection#startSession()`](/docs/api/connection.html#connection_Connection-startSession).
 
 ```javascript
+// Using Mongoose's default connection
 const session = await mongoose.startSession();
+
+// Using custom connection
+const db = await mongoose.createConnection(mongodbUri, { useUnifiedTopology: true, useNewUrlParser: true });
+const session = await db.startSession();
 ```
 
 In practice, you should use either the [`session.withTransaction()` helper](https://mongodb.github.io/node-mongodb-native/3.2/api/ClientSession.html#withTransaction)

From 980138d7ada7c40fedd2d1cee0660d3d6ecc0ac5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 14:56:27 -0400
Subject: [PATCH 2200/2348] docs(schema+validation): fix broken links

Fix #10396
---
 lib/schema.js                | 16 ++++++++--------
 test/docs/validation.test.js |  6 +++---
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 55df5c399d5..53089ee1492 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -2145,14 +2145,14 @@ module.exports = exports = Schema;
  *
  * ####Types:
  *
- * - [String](#schema-string-js)
- * - [Number](#schema-number-js)
- * - [Boolean](#schema-boolean-js) | Bool
- * - [Array](#schema-array-js)
- * - [Buffer](#schema-buffer-js)
- * - [Date](#schema-date-js)
- * - [ObjectId](#schema-objectid-js) | Oid
- * - [Mixed](#schema-mixed-js)
+ * - [String](/docs/schematypes.html#strings)
+ * - [Number](/docs/schematypes.html#numbers)
+ * - [Boolean](/docs/schematypes.html#booleans) | Bool
+ * - [Array](/docs/schematypes.html#arrays)
+ * - [Buffer](/docs/schematypes.html#buffers)
+ * - [Date](/docs/schematypes.html#dates)
+ * - [ObjectId](/docs/schematypes.html#objectids) | Oid
+ * - [Mixed](/docs/schematypes.html#mixed)
  *
  * Using this exposed access to the `Mixed` SchemaType, we can use them in our schema.
  *
diff --git a/test/docs/validation.test.js b/test/docs/validation.test.js
index 4e56bcb0592..f257bf38873 100644
--- a/test/docs/validation.test.js
+++ b/test/docs/validation.test.js
@@ -58,9 +58,9 @@ describe('validation docs', function() {
   /**
    * Mongoose has several built-in validators.
    *
-   * - All [SchemaTypes](./schematypes.html) have the built-in [required](./api.html#schematype_SchemaType-required) validator. The required validator uses the [SchemaType's `checkRequired()` function](./api.html#schematype_SchemaType-checkRequired) to determine if the value satisfies the required validator.
-   * - [Numbers](./api.html#schema-number-js) have [`min` and `max`](./schematypes.html#number-validators) validators.
-   * - [Strings](./api.html#schema-string-js) have [`enum`, `match`, `minLength`, and `maxLength`](./schematypes.html#string-validators) validators.
+   * - All [SchemaTypes](/docs/schematypes.html) have the built-in [required](./api.html#schematype_SchemaType-required) validator. The required validator uses the [SchemaType's `checkRequired()` function](./api.html#schematype_SchemaType-checkRequired) to determine if the value satisfies the required validator.
+   * - [Numbers](/docs/schematypes.html#numbers) have [`min` and `max`](./schematypes.html#number-validators) validators.
+   * - [Strings](/docs/schematypes.html#strings) have [`enum`, `match`, `minLength`, and `maxLength`](./schematypes.html#string-validators) validators.
    *
    * Each of the validator links above provide more information about how to enable them and customize their error messages.
    */

From 2259dc1c1b1f9089ca031657253d9db49a3daeaf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 2 Jul 2021 16:23:41 -0400
Subject: [PATCH 2201/2348] docs: add SchemaArray to docs

Fix #10397
---
 docs/source/api.js  | 9 +++++++--
 lib/schema/array.js | 6 ++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/docs/source/api.js b/docs/source/api.js
index a80c9419bb9..2026683d0bb 100644
--- a/docs/source/api.js
+++ b/docs/source/api.js
@@ -24,6 +24,7 @@ const files = [
   'lib/virtualtype.js',
   'lib/error/index.js',
   'lib/types/core_array.js',
+  'lib/schema/array.js',
   'lib/schema/documentarray.js',
   'lib/schema/SingleNestedPath.js',
   'lib/options/SchemaTypeOptions.js',
@@ -60,10 +61,14 @@ function parse() {
       replace('.js', '').
       replace('/index', '');
     const lastSlash = name.lastIndexOf('/');
+    const fullName = name;
     name = name.substr(lastSlash === -1 ? 0 : lastSlash + 1);
     if (name === 'core_array') {
       name = 'array';
     }
+    if (fullName === 'schema/array') {
+      name = 'SchemaArray';
+    }
     if (name === 'documentarray') {
       name = 'DocumentArrayPath';
     }
@@ -101,13 +106,13 @@ function parse() {
             ctx.type = 'property';
             ctx.static = true;
             ctx.name = tag.string;
-            ctx.string = `${ctx.constructor}.${ctx.name}`;
+            ctx.string = `${data.name}.${ctx.name}`;
             break;
           case 'function':
             ctx.type = 'function';
             ctx.static = true;
             ctx.name = tag.string;
-            ctx.string = `${ctx.constructor}.${ctx.name}()`;
+            ctx.string = `${data.name}.${ctx.name}()`;
             break;
           case 'return':
             tag.description = tag.description ?
diff --git a/lib/schema/array.js b/lib/schema/array.js
index bdfea596483..22eddfae7c6 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -146,6 +146,10 @@ SchemaArray.schemaName = 'Array';
 
 SchemaArray.options = { castNonArrays: true };
 
+/*!
+ * ignore
+ */
+
 SchemaArray.defaultOptions = {};
 
 /**
@@ -163,7 +167,6 @@ SchemaArray.defaultOptions = {};
  * @param {*} value - value for option
  * @return {undefined}
  * @function set
- * @static
  * @api public
  */
 SchemaArray.set = SchemaType.set;
@@ -196,7 +199,6 @@ SchemaArray._checkRequired = SchemaType.prototype.checkRequired;
  * @param {Function} fn
  * @return {Function}
  * @function checkRequired
- * @static
  * @api public
  */
 

From ccfb86e41f35bd061ad6fd125805f7e7cbed4659 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Jul 2021 14:26:46 -0400
Subject: [PATCH 2202/2348] fix(index.d.ts): allow extra VirtualTypeOptions for
 better plugin support

Fix #10412
Fix mongodb-js/mongoose-autopopulate#85
---
 index.d.ts                   |  3 +++
 test/typescript/main.test.js |  8 ++++++++
 test/typescript/virtuals.ts  | 15 +++------------
 3 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 5cbf2c14cbe..d1a5a87ca7d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1674,6 +1674,9 @@ declare module 'mongoose' {
 
     /** Additional options like `limit` and `lean`. */
     options?: QueryOptions;
+
+    /** Additional options for plugins */
+    [extra: string]: any;
   }
 
   class VirtualType {
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 2af14034de4..4905d579f68 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -208,6 +208,14 @@ describe('typescript syntax', function() {
     }
     assert.equal(errors.length, 0);
   });
+
+  it('virtuals', function() {
+    const errors = runTest('virtuals.ts');
+    if (process.env.D && errors.length) {
+      console.log(errors);
+    }
+    assert.equal(errors.length, 0);
+  });
 });
 
 function runTest(file, configOverride) {
diff --git a/test/typescript/virtuals.ts b/test/typescript/virtuals.ts
index cfb8604e5e2..93b56d911ee 100644
--- a/test/typescript/virtuals.ts
+++ b/test/typescript/virtuals.ts
@@ -37,22 +37,13 @@ personSchema.virtual('fullName')
     this.lastName = splittedName[1];
   });
 
-// Arrow functions should not be used for virtual getters/setters.
-// See https://mongoosejs.com/docs/faq.html#arrow-functions
-personSchema.virtual('wrongVirtual')
-  .get((value, virtual, doc) => {
-    return `${this.doesNotWork}!!`;
-  })
-  .set((value, virtual, doc) => {
-    this.value = 'is not document';
-  });
-
 // Populated virtuals
 petSchema.virtual('owner', {
   ref: 'Person',
   localField: 'ownerId',
   foreignField: '_id',
-  justOne: true
+  justOne: true,
+  autopopulate: true
 });
 
 const Person = model('Person', personSchema);
@@ -62,6 +53,6 @@ const Pet = model('Pet', petSchema);
   const person = await Person.create({ _id: 1, firstName: 'John', lastName: 'Wick' });
   await Pet.create({ name: 'Andy', ownerId: person._id });
 
-  const pet = await Pet.findOne().populate('owner');
+  const pet = await Pet.findOne().orFail().populate('owner');
   console.log(pet.owner.fullName); // John Wick
 })();

From d250ddc151b886abb46d64206c7cceab7ea4bcca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Jul 2021 14:42:19 -0400
Subject: [PATCH 2203/2348] fix(index.d.ts): allow using `type: Date` with Date
 paths in SchemaDefinitionType

Fix #10409
---
 index.d.ts                | 8 +++++---
 test/typescript/schema.ts | 9 +++++++++
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index d1a5a87ca7d..be86d723cee 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1245,15 +1245,17 @@ declare module 'mongoose' {
     virtualpath(name: string): VirtualType | null;
   }
 
-  type SchemaDefinitionWithBuiltInClass<T extends number | string | boolean | Function> = T extends number
+  type SchemaDefinitionWithBuiltInClass<T extends number | string | boolean | NativeDate | Function> = T extends number
     ? (typeof Number | 'number' | 'Number' | typeof Schema.Types.Number)
     : T extends string
     ? (typeof String | 'string' | 'String' | typeof Schema.Types.String)
     : T extends boolean
     ? (typeof Boolean | 'boolean' | 'Boolean' | typeof Schema.Types.Boolean)
+    : T extends NativeDate
+    ? (typeof NativeDate | 'date' | 'Date' | typeof Schema.Types.Date)
     : (Function | string);
 
-  type SchemaDefinitionProperty<T = undefined> = T extends string | number | Function
+  type SchemaDefinitionProperty<T = undefined> = T extends string | number | boolean | NativeDate | Function
     ? (SchemaDefinitionWithBuiltInClass<T> | SchemaTypeOptions<T>) :
     SchemaTypeOptions<T extends undefined ? any : T> |
     typeof SchemaType |
@@ -1437,7 +1439,7 @@ declare module 'mongoose' {
 
   export class SchemaTypeOptions<T> {
     type?:
-      T extends string | number | boolean | Function ? SchemaDefinitionWithBuiltInClass<T> :
+      T extends string | number | boolean | NativeDate | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema<any, any> ? T :
       T extends object[] ? (Schema<Document<Unpacked<T>>>[] | ReadonlyArray<Schema<Document<Unpacked<T>>>> | Schema<Document & Unpacked<T>>[] | ReadonlyArray<Schema<Document & Unpacked<T>>>) :
       T extends string[] ? (SchemaDefinitionWithBuiltInClass<string>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<string>>) :
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index cd5711989b8..5180b959dd5 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -154,4 +154,13 @@ function gh10370() {
       type: [actorSchema]
     }
   });
+}
+
+function gh10409() {
+  interface Something {
+    field: Date;
+  }
+  const someSchema = new Schema<Something, Model<Something>, Something>({
+    field: {type: Date}
+  });
 }
\ No newline at end of file

From 726ce8ba1499bb2ad629d887bba79e9fb33c03ca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Jul 2021 17:32:28 -0400
Subject: [PATCH 2204/2348] fix: hardcode @types/node version for now to avoid
 breaking changes from DefinitelyTyped/DefinitelyTyped#53669

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 09210053d1e..6175107a756 100644
--- a/package.json
+++ b/package.json
@@ -20,6 +20,7 @@
   "license": "MIT",
   "dependencies": {
     "@types/mongodb": "^3.5.27",
+    "@types/node": "15.x",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
     "mongodb": "3.6.8",

From 11596317d4ba2b860aa9b5994290b8cacb600782 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Jul 2021 17:35:27 -0400
Subject: [PATCH 2205/2348] chore: allow @types/node 14.x

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 6175107a756..24d0def4d13 100644
--- a/package.json
+++ b/package.json
@@ -20,7 +20,7 @@
   "license": "MIT",
   "dependencies": {
     "@types/mongodb": "^3.5.27",
-    "@types/node": "15.x",
+    "@types/node": "14.x || 15.x",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
     "mongodb": "3.6.8",

From 448259216502aa89ec7aaa8533662eaeece2b15a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Jul 2021 17:39:22 -0400
Subject: [PATCH 2206/2348] style: fix lint

---
 test/typescript/schema.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 5180b959dd5..7bcf2081ebf 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -161,6 +161,6 @@ function gh10409() {
     field: Date;
   }
   const someSchema = new Schema<Something, Model<Something>, Something>({
-    field: {type: Date}
+    field: { type: Date }
   });
 }
\ No newline at end of file

From c03cacb5659f640034e67d8a1ee1cae427c12762 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 3 Jul 2021 17:50:24 -0400
Subject: [PATCH 2207/2348] chore: release 5.13.2

---
 History.md   | 9 +++++++++
 package.json | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index b1f7042c287..38be2c9457d 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.13.2 / 2021-07-03
+===================
+ * fix: hardcode @types/node version for now to avoid breaking changes from DefinitelyTyped/DefinitelyTyped#53669 #10415
+ * fix(index.d.ts): allow using type: Date with Date paths in SchemaDefinitionType #10409
+ * fix(index.d.ts): allow extra VirtualTypeOptions for better plugin support #10412
+ * docs(api): add SchemaArray to docs #10397
+ * docs(schema+validation): fix broken links #10396
+ * docs(transactions): add note about creating a connection to transactions docs #10406
+
 5.13.1 / 2021-07-02
 ===================
  * fix(discriminator): allow using array as discriminator key in schema and as tied value #10303
diff --git a/package.json b/package.json
index 24d0def4d13..ce795c5747d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.1",
+  "version": "5.13.2",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From e1fcf29121b62ac627d1c7bf05fadaebe28ba76d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 8 Jul 2021 09:47:04 -0400
Subject: [PATCH 2208/2348] chore: update opencollective sponsors

---
 index.pug | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.pug b/index.pug
index c552a705065..6e85d5acb70 100644
--- a/index.pug
+++ b/index.pug
@@ -355,6 +355,12 @@ html(lang='en')
               <a rel="sponsored" href="https://www.gambledex.com/">
                 <img class="sponsor" src="https://codebarbarian-images.s3.amazonaws.com/gambedex.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://www.uudetkasinot.com/">
+                <img class="sponsor" src="https://images.opencollective.com/uudetkasinot-com/01a3658/logo/256.png" style="height: 100px">
+              </a>
+              <a rel="sponsored" href="https://www.vedonlyontibonukset.com/">
+                <img class="sponsor" src="https://images.opencollective.com/vedonlyontibonukset/69bffdc/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From ca34cfa125d2761cc085b1004ca7fd2c8032f4d0 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Fri, 9 Jul 2021 01:11:35 +0200
Subject: [PATCH 2209/2348] bump native driver to 3.6.10

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index ce795c5747d..18e698dd686 100644
--- a/package.json
+++ b/package.json
@@ -23,7 +23,7 @@
     "@types/node": "14.x || 15.x",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.8",
+    "mongodb": "3.6.10",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.5",

From ac545ef198dddf2f12b073bc9391a025e6250562 Mon Sep 17 00:00:00 2001
From: semir <semir.turgay@gmail.com>
Date: Fri, 9 Jul 2021 17:17:27 +0300
Subject: [PATCH 2210/2348] test(model): cover applying object defaults

---
 test/model.test.js | 51 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index de9b92bc9a0..7c5b092cc25 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -3826,6 +3826,57 @@ describe('Model', function() {
         });
       });
     });
+    it('is saved object with proper defaults', function(done) {
+      const DefaultTestObject = db.model('Test',
+        new Schema({
+          foo: {
+            x: { type: String },
+            y: { type: String }
+          },
+          boo: {
+            x: { type: Boolean, default: false }
+          },
+          bee: {
+            x: { type: Boolean, default: false },
+            y: { type: Boolean, default: false }
+          }
+        })
+      );
+      const myTest = new DefaultTestObject({
+        foo: { x: 'a', y: 'b' },
+        bee: {},
+        boo: {}
+      });
+
+      myTest.save(function(err, doc) {
+        assert.ifError(err);
+        assert.equal(doc.bee.x, false);
+        assert.equal(doc.bee.y, false);
+        assert.equal(doc.boo.x, false);
+
+        DefaultTestObject.findById(doc._id, function(err, doc) {
+          assert.ifError(err);
+
+          doc.bee = undefined; // unset
+          doc.boo = undefined; // unset
+          doc.save(function(err) {
+            assert.ifError(err);
+
+            DefaultTestObject.findById(doc._id, function(err, doc) {
+              assert.ifError(err);
+
+              doc.save(function(err, doc) {
+                assert.ifError(err);
+                assert.equal(doc.bee.x, false);
+                assert.equal(doc.bee.y, false);
+                assert.equal(doc.boo.x, false);
+                done();
+              });
+            });
+          });
+        });
+      });
+    });
   });
 
   it('path is cast to correct value when retreived from db', function(done) {

From 62508419b47ffb6eb101f5351f9aebd3ba62041e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 12 Jul 2021 17:33:57 -0400
Subject: [PATCH 2211/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 6e85d5acb70..8be245d1489 100644
--- a/index.pug
+++ b/index.pug
@@ -361,6 +361,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.vedonlyontibonukset.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vedonlyontibonukset/69bffdc/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://list.casino/">
+                <img class="sponsor" src="https://images.opencollective.com/list-casino/5d33a45/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From a22c908f7a97fe7c375c584526c15e56958d82cb Mon Sep 17 00:00:00 2001
From: semir <semir.turgay@gmail.com>
Date: Mon, 12 Jul 2021 14:19:00 +0300
Subject: [PATCH 2212/2348] fix(model): fixing model defaults for embedded
 objects

---
 lib/document.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/document.js b/lib/document.js
index 9d3077c7e61..9172018ae51 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -994,6 +994,9 @@ Document.prototype.$set = function $set(path, val, type, options) {
         delete this._doc[key];
         // Make sure we set `{}` back even if we minimize re: gh-8565
         options = Object.assign({}, options, { _skipMinimizeTopLevel: true });
+      } else {
+        // Make sure we set `{_skipMinimizeTopLevel: false}` if don't have overwrite: gh-10441
+        options = Object.assign({}, options, { _skipMinimizeTopLevel: false });
       }
 
       const someCondition = typeof path[key] === 'object' &&

From 982a3898ea97af6b39acf2cf25ddad95baa42cc4 Mon Sep 17 00:00:00 2001
From: DouglasGabr <douglasgabriel99@gmail.com>
Date: Wed, 14 Jul 2021 22:08:39 -0300
Subject: [PATCH 2213/2348] fix(types): remove discriminator type requirement

Since Model enforces Document when needed,
the discriminator type parameter don't need to extend it
---
 index.d.ts | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index be86d723cee..0095dfdd0eb 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -618,8 +618,8 @@ declare module 'mongoose' {
 
   interface AcceptsDiscriminator {
     /** Adds a discriminator type. */
-    discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string | number | ObjectId): Model<D>;
-    discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
+    discriminator<D>(name: string | number, schema: Schema<D>, value?: string | number | ObjectId): Model<D>;
+    discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
   }
 
   interface AnyObject { [k: string]: any }
@@ -1703,8 +1703,8 @@ declare module 'mongoose' {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
+        discriminator<D>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
 
         /**
          * Adds an enum validator if this is an array of strings or numbers. Equivalent to
@@ -1760,8 +1760,8 @@ declare module 'mongoose' {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator<D extends Document>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T extends Document, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
+        discriminator<D>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
 
         /** The schema used for documents in this array */
         schema: Schema;

From 5edb25d63fdff340e79e4f6fcdad403411bf369a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 11:18:31 -0400
Subject: [PATCH 2214/2348] fix(index.d.ts): consistently use NativeDate
 instead of Date for Date validators and timestamps functions

Fix #10246
---
 index.d.ts | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index be86d723cee..f7cb2ddea77 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -120,7 +120,7 @@ declare module 'mongoose' {
    * [timestamps](/docs/guide.html#timestamps). You may stub out this function
    * using a tool like [Sinon](https://www.npmjs.com/package/sinon) for testing.
    */
-  export function now(): Date;
+  export function now(): NativeDate;
 
   /** Declares a global plugin executed on all Schemas. */
   export function plugin(fn: (schema: Schema, opts?: any) => void, opts?: any): typeof mongoose;
@@ -1432,7 +1432,7 @@ declare module 'mongoose' {
   interface SchemaTimestampsConfig {
     createdAt?: boolean | string;
     updatedAt?: boolean | string;
-    currentTime?: () => (Date | number);
+    currentTime?: () => (NativeDate | number);
   }
 
   type Unpacked<T> = T extends (infer U)[] ? U : T;
@@ -1533,13 +1533,13 @@ declare module 'mongoose' {
     subtype?: number
 
     /** The minimum value allowed for this path. Only allowed for numbers and dates. */
-    min?: number | Date | [number, string] | [Date, string] | readonly [number, string] | readonly [Date, string];
+    min?: number | NativeDate | [number, string] | [NativeDate, string] | readonly [number, string] | readonly [NativeDate, string];
 
     /** The maximum value allowed for this path. Only allowed for numbers and dates. */
-    max?: number | Date | [number, string] | [Date, string] | readonly [number, string] | readonly [Date, string];
+    max?: number | NativeDate | [number, string] | [NativeDate, string] | readonly [number, string] | readonly [NativeDate, string];
 
     /** Defines a TTL index on this path. Only allowed for dates. */
-    expires?: number | Date;
+    expires?: number | NativeDate;
 
     /** If `true`, Mongoose will skip gathering indexes on subpaths. Only allowed for subdocuments and subdocument arrays. */
     excludeIndexes?: boolean;
@@ -1743,10 +1743,10 @@ declare module 'mongoose' {
         expires(when: number | string): this;
 
         /** Sets a maximum date validator. */
-        max(value: Date, message: string): this;
+        max(value: NativeDate, message: string): this;
 
         /** Sets a minimum date validator. */
-        min(value: Date, message: string): this;
+        min(value: NativeDate, message: string): this;
       }
 
       class Decimal128 extends SchemaType {
@@ -2441,7 +2441,7 @@ declare module 'mongoose' {
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
   type TreatAsPrimitives = actualPrimitives |
       // eslint-disable-next-line no-undef
-    Date | RegExp | symbol | Error | BigInt | Types.ObjectId;
+    NativeDate | RegExp | symbol | Error | BigInt | Types.ObjectId;
 
   type LeanType<T> =
     0 extends (1 & T) ? T : // any

From 34d279658e5b5268b2fb7e4db2e486e1f5280de3 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 11:48:42 -0400
Subject: [PATCH 2215/2348] fix(index.d.ts): add `discriminator()` for single
 nested subdocs to type definitions

Re: #10435
---
 index.d.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index f1fab76e9dc..3b4021d5073 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1799,12 +1799,15 @@ declare module 'mongoose' {
         auto(turnOn: boolean): this;
       }
 
-      class Embedded extends SchemaType {
+      class Embedded extends SchemaType implements AcceptsDiscriminator {
         /** This schema type's name, to defend against minifiers that mangle function names. */
         static schemaName: string;
 
         /** The document's schema */
         schema: Schema;
+
+        discriminator<D>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
+        discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
       }
 
       class String extends SchemaType {

From ad8ca7671e8233b16772f7550d8a57e9dc6c0bb2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 12:18:31 -0400
Subject: [PATCH 2216/2348] fix(index.d.ts): allow passing ResultType generic
 to `Schema#path()`

Fix #10435
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 3b4021d5073..ae90b7ab113 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1167,7 +1167,7 @@ declare module 'mongoose' {
     obj: any;
 
     /** Gets/sets schema paths. */
-    path(path: string): SchemaType;
+    path<ResultType extends SchemaType = SchemaType>(path: string): ResultType;
     path(path: string, constructor: any): this;
 
     /** Lists all paths and their type in the schema. */

From c1ce3c92f2700d7a7b5ed2c6da86e963a1043f48 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 12:35:28 -0400
Subject: [PATCH 2217/2348] test(model): repro #9673

---
 test/model.test.js | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index de9b92bc9a0..1f65e257f36 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7323,7 +7323,8 @@ describe('Model', function() {
 
         yield User.insertMany([
           new User({ name: 'Hafez1_gh-9673-2' }),
-          new User({ name: 'Hafez2_gh-9673-2' })
+          new User({ name: 'Hafez2_gh-9673-2' }),
+          new User({ name: 'Hafez3_gh-9673-2' })
         ]);
 
         const users = yield User.find().sort('name');
@@ -7339,7 +7340,8 @@ describe('Model', function() {
           usersAfterUpdate.map(user => user.name),
           [
             'Hafez1_gh-9673-2-updated',
-            'Hafez2_gh-9673-2-updated'
+            'Hafez2_gh-9673-2-updated',
+            'Hafez3_gh-9673-2'
           ]
         );
       });
@@ -7412,7 +7414,7 @@ describe('Model', function() {
         assert.equal(user2.isNew, false);
       });
     });
-    it('sets `isNew` to false when a document succeds and `isNew` does not change when some fail', () => {
+    it('sets `isNew` to false when a document succeeds and `isNew` does not change when some fail', () => {
       return co(function* () {
         const userSchema = new Schema({
           name: { type: String, unique: true }

From 16b6a37e813b4f0a722c0edf38f9f124ebbfcafc Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 12:35:43 -0400
Subject: [PATCH 2218/2348] fix(model): avoid throwing error when `bulkSave()`
 called on a document with no changes

Fix #10437
---
 lib/model.js | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 373dea5536b..ee3fae6a1fe 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3729,18 +3729,21 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents, op
     }
 
     const delta = document.$__delta();
-    const where = document.$__where(delta[0]);
-    const changes = delta[1];
-
-    _applyCustomWhere(document, where);
-
-    document.$__version(where, delta);
 
     if (document.isNew) {
+      // new document
       accumulator.push({
         insertOne: { document }
       });
-    } else if (!utils.isEmptyObject(changes)) {
+    } else if (delta != null && !utils.isEmptyObject(delta[0])) {
+      // document with changes
+      const where = document.$__where(delta[0]);
+      const changes = delta[1];
+
+      _applyCustomWhere(document, where);
+
+      document.$__version(where, delta);
+
       accumulator.push({
         updateOne: {
           filter: where,

From acd262ce43c21bac0c1e2766c2cdf36244aa649f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 12:53:48 -0400
Subject: [PATCH 2219/2348] test(schema): repro #10436

---
 test/schema.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/test/schema.test.js b/test/schema.test.js
index 61098ed645c..f5adc214066 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2604,6 +2604,27 @@ describe('schema', function() {
     assert.equal(schema.virtuals.displayAs.applyGetters(null, { name: 'test' }), 'test');
   });
 
+  it('loadClass with static getter (gh-10436)', function() {
+    const schema = new mongoose.Schema({
+      firstName: String,
+      lastName: String
+    });
+
+    class UserClass extends mongoose.Model {
+      get fullName() {
+        return `${this.firstName} ${this.lastName}`;
+      }
+
+      static get greeting() {
+        return 'Hello World';
+      }
+    }
+
+    const User = mongoose.model(UserClass, schema);
+
+    assert.equal(User.greeting, 'Hello World');
+  });
+
   it('supports setting `ref` on array SchemaType (gh-10029)', function() {
     const testSchema = new mongoose.Schema({
       doesntpopulate: {

From 169f9e15a60bc117820457904ff16edb7ac622b0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 12:53:59 -0400
Subject: [PATCH 2220/2348] fix(schema): allow calling `Schema#loadClass()`
 with class that has a static getter with no setter

Fix #10436
---
 lib/schema.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 53089ee1492..8072ac453a6 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1937,7 +1937,9 @@ Schema.prototype.loadClass = function(model, virtualsOnly) {
         return;
       }
       const prop = Object.getOwnPropertyDescriptor(model, name);
-      this.static(name, prop.value);
+      if (prop.hasOwnProperty('value')) {
+        this.static(name, prop.value);
+      }
     }, this);
   }
 

From c6a646c588b855da73b0f694caa36e3ae0b535ce Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 13:24:41 -0400
Subject: [PATCH 2221/2348] test(timestamps): repro #10447

---
 test/timestamps.test.js | 44 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/test/timestamps.test.js b/test/timestamps.test.js
index b31369d6089..799d023030f 100644
--- a/test/timestamps.test.js
+++ b/test/timestamps.test.js
@@ -875,4 +875,48 @@ describe('timestamps', function() {
       assert.ok(fromDb.content.a.updatedAt.valueOf() > ts.valueOf());
     });
   });
+
+  it('sets createdAt when using $push/$addToSet on path with positional operator (gh-10447)', function() {
+    const userSchema = new Schema({
+      email: String
+    }, { timestamps: true });
+    const eventSchema = new Schema({
+      users: [userSchema],
+      message: String
+    }, { timestamps: true });
+
+    const churchSchema = new Schema({
+      events: [eventSchema]
+    }, { timestamps: true });
+
+    const Church = db.model('Test', churchSchema);
+
+    return co(function*() {
+      yield Church.create({
+        events: [{
+          churchId: 1,
+          message: 'test',
+          users: [{
+            churchId: 1,
+            email: 'test@google.com'
+          }]
+        }]
+      });
+
+      const church = yield Church.findOneAndUpdate({
+        events: { $elemMatch: { users: { $not: { $elemMatch: { email: 'test2@google.com' } } } } }
+      }, {
+        $addToSet: {
+          'events.$.users': { churchId: 1, email: 'test2@google.com' }
+        }
+      }, {
+        new: true
+      });
+
+      assert.equal(church.events.length, 1);
+      assert.equal(church.events[0].users.length, 2);
+      assert.equal(church.events[0].users[1].email, 'test2@google.com');
+      assert.ok(church.events[0].users[1].createdAt);
+    });
+  });
 });

From 66fd25f98cb52f32d8ed8ddb05d9ff49906747a2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 13:24:53 -0400
Subject: [PATCH 2222/2348] fix(timestamps): apply timestamps when creating new
 subdocs with `$addToSet` and with positional operator

Fix #10447
---
 .../update/applyTimestampsToChildren.js       | 63 ++++++++++---------
 1 file changed, 35 insertions(+), 28 deletions(-)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 680d692d02b..76bac6e6608 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -19,34 +19,10 @@ function applyTimestampsToChildren(now, update, schema) {
 
   if (hasDollarKey) {
     if (update.$push) {
-      for (const key of Object.keys(update.$push)) {
-        const $path = schema.path(key);
-        if (update.$push[key] &&
-            $path &&
-            $path.$isMongooseDocumentArray &&
-            $path.schema.options.timestamps) {
-          const timestamps = $path.schema.options.timestamps;
-          const createdAt = handleTimestampOption(timestamps, 'createdAt');
-          const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
-          if (update.$push[key].$each) {
-            update.$push[key].$each.forEach(function(subdoc) {
-              if (updatedAt != null) {
-                subdoc[updatedAt] = now;
-              }
-              if (createdAt != null) {
-                subdoc[createdAt] = now;
-              }
-            });
-          } else {
-            if (updatedAt != null) {
-              update.$push[key][updatedAt] = now;
-            }
-            if (createdAt != null) {
-              update.$push[key][createdAt] = now;
-            }
-          }
-        }
-      }
+      _applyTimestampToUpdateOperator(update.$push);
+    }
+    if (update.$addToSet) {
+      _applyTimestampToUpdateOperator(update.$addToSet);
     }
     if (update.$set != null) {
       const keys = Object.keys(update.$set);
@@ -60,6 +36,37 @@ function applyTimestampsToChildren(now, update, schema) {
   for (const key of updateKeys) {
     applyTimestampsToUpdateKey(schema, key, update, now);
   }
+
+  function _applyTimestampToUpdateOperator(op) {
+    for (const key of Object.keys(op)) {
+      const $path = schema.path(key.replace(/\.\$\./i, '.').replace(/.\$$/, ''));
+      if (op[key] &&
+          $path &&
+          $path.$isMongooseDocumentArray &&
+          $path.schema.options.timestamps) {
+        const timestamps = $path.schema.options.timestamps;
+        const createdAt = handleTimestampOption(timestamps, 'createdAt');
+        const updatedAt = handleTimestampOption(timestamps, 'updatedAt');
+        if (op[key].$each) {
+          op[key].$each.forEach(function(subdoc) {
+            if (updatedAt != null) {
+              subdoc[updatedAt] = now;
+            }
+            if (createdAt != null) {
+              subdoc[createdAt] = now;
+            }
+          });
+        } else {
+          if (updatedAt != null) {
+            op[key][updatedAt] = now;
+          }
+          if (createdAt != null) {
+            op[key][createdAt] = now;
+          }
+        }
+      }
+    }
+  }
 }
 
 function applyTimestampsToDocumentArray(arr, schematype, now) {

From 392462869e8a3d3290c06e770d8ba7f3a1199731 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 16 Jul 2021 13:53:29 -0400
Subject: [PATCH 2223/2348] chore: release 5.13.3

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 38be2c9457d..d62dd16663f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.13.3 / 2021-07-16
+===================
+ * fix(model): avoid throwing error when bulkSave() called on a document with no changes #10437
+ * fix(timestamps): apply timestamps when creating new subdocs with `$addToSet` and with positional operator #10447
+ * fix(schema): allow calling Schema#loadClass() with class that has a static getter with no setter #10436
+ * fix(model): handle re-applying object defaults after explicitly unsetting #10442 [semirturgay](https://github.com/semirturgay)
+ * fix: bump mongodb driver -> 3.6.10 #10440 [AbdelrahmanHafez](https://github.com/AbdelrahmanHafez)
+ * fix(index.d.ts): consistently use NativeDate instead of Date for Date validators and timestamps functions #10426
+ * fix(index.d.ts): allow calling `discriminator()` with non-document #10452 #10421 [DouglasGabr](https://github.com/DouglasGabr)
+ * fix(index.d.ts): allow passing ResultType generic to Schema#path() #10435
+
 5.13.2 / 2021-07-03
 ===================
  * fix: hardcode @types/node version for now to avoid breaking changes from DefinitelyTyped/DefinitelyTyped#53669 #10415
diff --git a/package.json b/package.json
index 18e698dd686..81612d8d925 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.2",
+  "version": "5.13.3",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From e4be278e438c67b356d25150e82f0a6985df648b Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 17 Jul 2021 13:38:29 +0200
Subject: [PATCH 2224/2348] test(model): assert Model.bulkSave(...) works if
 some document is not modified

---
 test/model.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/model.test.js b/test/model.test.js
index e6a330eb806..80aac53a981 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7557,6 +7557,20 @@ describe('Model', function() {
         assert.equal(usersFromDatabase[1].name, 'name from pre-save');
       });
     });
+    it('works if some document is not modified (gh-10437)', () => {
+      const userSchema = new Schema({
+        name: String
+      });
+
+      const User = db.model('User', userSchema);
+
+      return co(function*() {
+        const user = yield User.create({ name: 'Hafez' });
+
+        const res = yield User.bulkSave([user]);
+        assert.ok(res.result.ok);
+      });
+    });
   });
 
   describe('Setting the explain flag', function() {

From 8122374f02e67e68a20190031b765abd8c9fbae7 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Sat, 17 Jul 2021 13:54:35 +0200
Subject: [PATCH 2225/2348] refactor(test): prefer co/yield over callbacks re
 #10441

---
 test/model.test.js | 64 +++++++++++++++++++---------------------------
 1 file changed, 27 insertions(+), 37 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index e6a330eb806..9a82e243f13 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -3826,57 +3826,47 @@ describe('Model', function() {
         });
       });
     });
-    it('is saved object with proper defaults', function(done) {
-      const DefaultTestObject = db.model('Test',
-        new Schema({
-          foo: {
-            x: { type: String },
-            y: { type: String }
-          },
-          boo: {
-            x: { type: Boolean, default: false }
-          },
-          bee: {
-            x: { type: Boolean, default: false },
-            y: { type: Boolean, default: false }
-          }
-        })
-      );
-      const myTest = new DefaultTestObject({
+    it('is saved object with proper defaults', function() {
+      const schema = new Schema({
+        foo: {
+          x: { type: String },
+          y: { type: String }
+        },
+        boo: {
+          x: { type: Boolean, default: false }
+        },
+        bee: {
+          x: { type: Boolean, default: false },
+          y: { type: Boolean, default: false }
+        }
+      });
+      const Test = db.model('Test', schema);
+
+      const doc = new Test({
         foo: { x: 'a', y: 'b' },
         bee: {},
         boo: {}
       });
 
-      myTest.save(function(err, doc) {
-        assert.ifError(err);
+      return co(function*() {
+        yield doc.save();
         assert.equal(doc.bee.x, false);
         assert.equal(doc.bee.y, false);
         assert.equal(doc.boo.x, false);
 
-        DefaultTestObject.findById(doc._id, function(err, doc) {
-          assert.ifError(err);
+        doc.bee = undefined;
+        doc.boo = undefined;
 
-          doc.bee = undefined; // unset
-          doc.boo = undefined; // unset
-          doc.save(function(err) {
-            assert.ifError(err);
+        yield doc.save();
 
-            DefaultTestObject.findById(doc._id, function(err, doc) {
-              assert.ifError(err);
+        const docAfterUnsetting = yield Test.findById(doc._id);
 
-              doc.save(function(err, doc) {
-                assert.ifError(err);
-                assert.equal(doc.bee.x, false);
-                assert.equal(doc.bee.y, false);
-                assert.equal(doc.boo.x, false);
-                done();
-              });
-            });
-          });
-        });
+        assert.equal(docAfterUnsetting.bee.x, false);
+        assert.equal(docAfterUnsetting.bee.y, false);
+        assert.equal(docAfterUnsetting.boo.x, false);
       });
     });
+
   });
 
   it('path is cast to correct value when retreived from db', function(done) {

From 0c82c5464e34c605e13149768037c19c5bbfad5a Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Sat, 17 Jul 2021 14:27:39 -0300
Subject: [PATCH 2226/2348] lint: remove unnecessary 'eslint-disable' comments

---
 index.d.ts                    | 20 --------------------
 lib/schema/array.js           |  2 +-
 lib/types/embedded.js         |  2 +-
 test/typescript/middleware.ts |  1 -
 4 files changed, 2 insertions(+), 23 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index ae90b7ab113..4c66e4fac62 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -37,7 +37,6 @@ declare module 'mongoose' {
    * Mongoose constructor. The exports object of the `mongoose` module is an instance of this
    * class. Most apps will only use this one instance.
    */
-  // eslint-disable-next-line @typescript-eslint/ban-types
   export const Mongoose: new (options?: object | null) => typeof mongoose;
 
   /**
@@ -626,12 +625,10 @@ declare module 'mongoose' {
   type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document<any, any, T> & TMethods;
 
   export const Model: Model<any>;
-  // eslint-disable-next-line no-undef
   interface Model<T, TQueryHelpers = {}, TMethods = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
     new(doc?: T | any): EnforceDocument<T, TMethods>;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
-    // eslint-disable-next-line @typescript-eslint/ban-types
     aggregate<R = any>(pipeline: any[], cb: Function): Promise<Array<R>>;
 
     /** Base Mongoose instance the model uses. */
@@ -722,7 +719,6 @@ declare module 'mongoose' {
      * Event emitter that reports any errors that occurred. Useful for global error
      * handling.
      */
-    // eslint-disable-next-line no-undef
     events: NodeJS.EventEmitter;
 
     /**
@@ -802,7 +798,6 @@ declare module 'mongoose' {
     watch(pipeline?: Array<Record<string, unknown>>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
 
     /** Adds a `$where` clause to this query */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     $where(argument: string | Function): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Registered discriminators for this model. */
@@ -998,7 +993,6 @@ declare module 'mongoose' {
   }
 
   interface MapReduceOptions<T, Key, Val> {
-    // eslint-disable-next-line @typescript-eslint/ban-types
     map: Function | string;
     reduce: (key: Key, vals: T[]) => Val;
     /** query filter object. */
@@ -1152,11 +1146,9 @@ declare module 'mongoose' {
      * [statics](http://mongoosejs.com/docs/guide.html#statics), and
      * [methods](http://mongoosejs.com/docs/guide.html#methods).
      */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     loadClass(model: Function, onlyVirtuals?: boolean): this;
 
     /** Adds an instance method to documents constructed from Models compiled from this schema. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     method(name: string, fn: (this: EnforceDocument<DocType, TInstanceMethods>, ...args: any[]) => any, opts?: any): this;
     method(obj: { [name: string]: (this: EnforceDocument<DocType, TInstanceMethods>, ...args: any[]) => any }): this;
 
@@ -1227,9 +1219,7 @@ declare module 'mongoose' {
     set(path: string, value: any, _tags?: any): this;
 
     /** Adds static "class" methods to Models compiled from this schema. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     static(name: string, fn: (this: M, ...args: any[]) => any): this;
-    // eslint-disable-next-line @typescript-eslint/ban-types
     static(obj: { [name: string]: (this: M, ...args: any[]) => any }): this;
 
     /** Object of currently defined statics on this schema. */
@@ -1452,7 +1442,6 @@ declare module 'mongoose' {
     alias?: string;
 
     /** Function or object describing how to validate this schematype. See [validation docs](https://mongoosejs.com/docs/validation.html). */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     validate?: RegExp | [RegExp, string] | Function | [Function, string] | ValidateOpts<T> | ValidateOpts<T>[];
 
     /** Allows overriding casting logic for this individual path. If a string, the given string overwrites Mongoose's default cast error message. */
@@ -1548,7 +1537,6 @@ declare module 'mongoose' {
     _id?: boolean;
 
     /** If set, specifies the type of this map's values. Mongoose will cast this map's values to the given type. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     of?: Function | SchemaDefinitionProperty<any>;
 
     /** If true, uses Mongoose's default `_id` settings. Only allowed for ObjectIds */
@@ -1975,7 +1963,6 @@ declare module 'mongoose' {
     // @todo: this doesn't seem right
     exec(callback?: (err: CallbackError, result: ResultType) => void): Promise<ResultType> | any;
 
-    // eslint-disable-next-line @typescript-eslint/ban-types
     $where(argument: string | Function): QueryWithHelpers<DocType[], DocType, THelpers, RawDocType>;
 
     /** Specifies an `$all` query condition. When called with one argument, the most recent path passed to `where()` is used. */
@@ -2054,9 +2041,7 @@ declare module 'mongoose' {
     distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     elemMatch(val: Function | any): this;
-    // eslint-disable-next-line @typescript-eslint/ban-types
     elemMatch(path: string, val: Function | any): this;
 
     /**
@@ -2443,7 +2428,6 @@ declare module 'mongoose' {
 
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
   type TreatAsPrimitives = actualPrimitives |
-      // eslint-disable-next-line no-undef
     NativeDate | RegExp | symbol | Error | BigInt | Types.ObjectId;
 
   type LeanType<T> =
@@ -2694,7 +2678,6 @@ declare module 'mongoose' {
     constructor(path: string, options?: any, instance?: string);
 
     /** Get/set the function used to cast arbitrary values to this type. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     static cast(caster?: Function | boolean): Function;
 
     static checkRequired(checkRequired?: (v: any) => boolean): (v: any) => boolean;
@@ -2715,7 +2698,6 @@ declare module 'mongoose' {
     default(val: any): any;
 
     /** Adds a getter to this schematype. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     get(fn: Function): this;
 
     /**
@@ -2743,7 +2725,6 @@ declare module 'mongoose' {
     select(val: boolean): this;
 
     /** Adds a setter to this schematype. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     set(fn: Function): this;
 
     /** Declares a sparse index. */
@@ -2759,7 +2740,6 @@ declare module 'mongoose' {
     unique(bool: boolean): this;
 
     /** Adds validator(s) for this document path. */
-    // eslint-disable-next-line @typescript-eslint/ban-types
     validate(obj: RegExp | Function | any, errorMsg?: string,
       type?: string): this;
   }
diff --git a/lib/schema/array.js b/lib/schema/array.js
index 22eddfae7c6..872eeeba68f 100644
--- a/lib/schema/array.js
+++ b/lib/schema/array.js
@@ -451,7 +451,7 @@ SchemaArray.prototype._castForPopulate = function _castForPopulate(value, doc) {
  */
 
 SchemaArray.prototype.discriminator = function(name, schema) {
-  let arr = this; // eslint-disable-line consistent-this
+  let arr = this;
   while (arr.$isMongooseArray && !arr.$isMongooseDocumentArray) {
     arr = arr.casterConstructor;
     if (arr == null || typeof arr === 'function') {
diff --git a/lib/types/embedded.js b/lib/types/embedded.js
index 5bcdc412f06..956af1da723 100644
--- a/lib/types/embedded.js
+++ b/lib/types/embedded.js
@@ -397,7 +397,7 @@ EmbeddedDocument.prototype.ownerDocument = function() {
 
 EmbeddedDocument.prototype.$__fullPath = function(path) {
   if (!this.$__.fullPath) {
-    let parent = this; // eslint-disable-line consistent-this
+    let parent = this;
     if (!parent[documentArrayParent]) {
       return path;
     }
diff --git a/test/typescript/middleware.ts b/test/typescript/middleware.ts
index cc172467f51..432e7a37e7c 100644
--- a/test/typescript/middleware.ts
+++ b/test/typescript/middleware.ts
@@ -39,7 +39,6 @@ schema.post<ITest>('save', function() {
   console.log(this.name);
 });
 
-// eslint-disable-next-line @typescript-eslint/ban-types
 schema.post<ITest>('save', function(err: Error, res: ITest, next: Function) {
   console.log(this.name, err.stack);
 });

From 40c369d6f7a4a9c04a1a793dd2b9fee322e9056a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 19 Jul 2021 18:23:48 -0400
Subject: [PATCH 2227/2348] chore: update opencollective sponsors

---
 index.pug | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/index.pug b/index.pug
index 8be245d1489..0ba5e2f969f 100644
--- a/index.pug
+++ b/index.pug
@@ -331,18 +331,12 @@ html(lang='en')
               <a rel="sponsored" href="https://www.nettikasinot.media/">
                 <img class="sponsor" src="https://images.opencollective.com/nettikasinot-media/2dba7da/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://www.leoboost.com/buy-instagram-likes">
-                <img class="sponsor" src="https://images.opencollective.com/leo-boost1/f744783/logo/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://poprey.com/">
                 <img class="sponsor" src="/docs/images/logo-poprey-com-white-100.png" style="height: 100px">
               </a>
               <a rel="sponsored" href="https://casinomartini.com/nz/new-online-casinos/">
                 <img class="sponsor" src="https://images.opencollective.com/casino-martini/8efce1c/logo/256.png" style="height: 100px">
               </a>
-              <a rel="sponsored" href="https://ufa96bet.com/">
-                <img class="sponsor" src="https://images.opencollective.com/ufabet/257fa8f/avatar/256.png" style="height: 100px">
-              </a>
               <a rel="sponsored" href="https://slot-xo888.com/">
                 <img class="sponsor" src="https://images.opencollective.com/slotxo/694a96c/avatar/256.png" style="height: 100px">
               </a>
@@ -364,6 +358,9 @@ html(lang='en')
               <a rel="sponsored" href="https://list.casino/">
                 <img class="sponsor" src="https://images.opencollective.com/list-casino/5d33a45/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://www.bonusfinder.co.uk/">
+                <img class="sponsor" src="https://images.opencollective.com/bonusfinder-uk/ecdd3af/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 59b411f90a33312a2857d39abe407b1361847d26 Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Mon, 19 Jul 2021 19:58:46 -0300
Subject: [PATCH 2228/2348] Add `MongooseOptions` interface

---
 index.d.ts | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 132 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4c66e4fac62..59f18e54558 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -37,7 +37,7 @@ declare module 'mongoose' {
    * Mongoose constructor. The exports object of the `mongoose` module is an instance of this
    * class. Most apps will only use this one instance.
    */
-  export const Mongoose: new (options?: object | null) => typeof mongoose;
+  export const Mongoose: new (options?: MongooseOptions | null) => typeof mongoose;
 
   /**
    * The Mongoose Number [SchemaType](/docs/schematypes.html). Used for
@@ -92,7 +92,7 @@ declare module 'mongoose' {
   export function disconnect(cb: (err: CallbackError) => void): void;
 
   /** Gets mongoose options */
-  export function get(key: string): any;
+  export function get<K extends keyof MongooseOptions>(key: K): MongooseOptions[K];
 
   /**
    * Returns true if Mongoose can cast the given value to an ObjectId, or
@@ -128,7 +128,7 @@ declare module 'mongoose' {
   export function pluralize(fn?: ((str: string) => string) | null): ((str: string) => string) | null;
 
   /** Sets mongoose options */
-  export function set(key: string, value: any): void;
+  export function set<K extends keyof MongooseOptions>(key: K, value: MongooseOptions[K]): typeof mongoose;
 
   /**
    * _Requires MongoDB >= 3.6.0._ Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
@@ -145,6 +145,135 @@ declare module 'mongoose' {
 
   type Mongoose = typeof mongoose;
 
+  interface MongooseOptions {
+    /** true by default. Set to false to skip applying global plugins to child schemas */
+    applyPluginsToChildSchemas?: boolean;
+
+    /**
+     * false by default. Set to true to apply global plugins to discriminator schemas.
+     * This typically isn't necessary because plugins are applied to the base schema and
+     * discriminators copy all middleware, methods, statics, and properties from the base schema.
+     */
+    applyPluginsToDiscriminators?: boolean;
+
+    /**
+     * Set to `true` to make Mongoose call` Model.createCollection()` automatically when you
+     * create a model with `mongoose.model()` or `conn.model()`. This is useful for testing
+     * transactions, change streams, and other features that require the collection to exist.
+     */
+    autoCreate?: boolean;
+
+    /**
+     * true by default. Set to false to disable automatic index creation
+     * for all models associated with this Mongoose instance.
+     */
+    autoIndex?: boolean;
+
+    /** enable/disable mongoose's buffering mechanism for all connections and models */
+    bufferCommands?: boolean;
+
+    bufferTimeoutMS?: number;
+
+    /** false by default. Set to `true` to `clone()` all schemas before compiling into a model. */
+    cloneSchemas?: boolean;
+
+    /**
+     * If `true`, prints the operations mongoose sends to MongoDB to the console.
+     * If a writable stream is passed, it will log to that stream, without colorization.
+     * If a callback function is passed, it will receive the collection name, the method
+     * name, then all arguments passed to the method. For example, if you wanted to
+     * replicate the default logging, you could output from the callback
+     * `Mongoose: ${collectionName}.${methodName}(${methodArgs.join(', ')})`.
+     */
+    debug?:
+      | boolean
+      | { color?: boolean; shell?: boolean }
+      | WritableStream
+      | ((collectionName: string, methodName: string, ...methodArgs: any[]) => void);
+
+    /** If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query */
+    maxTimeMS?: number;
+
+    /**
+     * true by default. Mongoose adds a getter to MongoDB ObjectId's called `_id` that
+     * returns `this` for convenience with populate. Set this to false to remove the getter.
+     */
+    objectIdGetter?: boolean;
+
+    /**
+     * Set to `true` to default to overwriting models with the same name when calling
+     * `mongoose.model()`, as opposed to throwing an `OverwriteModelError`.
+     */
+    overwriteModels?: boolean;
+
+    /**
+     * If `false`, changes the default `returnOriginal` option to `findOneAndUpdate()`,
+     * `findByIdAndUpdate`, and `findOneAndReplace()` to false. This is equivalent to
+     * setting the `new` option to `true` for `findOneAndX()` calls by default. Read our
+     * `findOneAndUpdate()` [tutorial](https://mongoosejs.com/docs/tutorials/findoneandupdate.html)
+     * for more information.
+     */
+    returnOriginal?: boolean;
+
+    /**
+     * false by default. Set to true to enable [update validators](
+     * https://mongoosejs.com/docs/validation.html#update-validators
+     * ) for all validators by default.
+     */
+    runValidators?: boolean;
+
+    sanitizeProjection?: boolean;
+
+    /**
+     * true by default. Set to false to opt out of Mongoose adding all fields that you `populate()`
+     * to your `select()`. The schema-level option `selectPopulatedPaths` overwrites this one.
+     */
+    selectPopulatedPaths?: boolean;
+
+    setDefaultsOnInsert?: boolean;
+
+    /** true by default, may be `false`, `true`, or `'throw'`. Sets the default strict mode for schemas. */
+    strict?: boolean | 'throw';
+
+    /**
+     * false by default, may be `false`, `true`, or `'throw'`. Sets the default
+     * [strictQuery](https://mongoosejs.com/docs/guide.html#strictQuery) mode for schemas.
+     */
+    strictQuery?: boolean | 'throw';
+
+    /**
+     * `{ transform: true, flattenDecimals: true }` by default. Overwrites default objects to
+     * `toJSON()`, for determining how Mongoose documents get serialized by `JSON.stringify()`
+     */
+    toJSON?: ToObjectOptions;
+
+    /** `{ transform: true, flattenDecimals: true }` by default. Overwrites default objects to `toObject()` */
+    toObject?: ToObjectOptions;
+
+    /** true by default, may be `false` or `true`. Sets the default typePojoToMixed for schemas. */
+    typePojoToMixed?: boolean;
+
+    /**
+     * false by default. Set to `true` to make Mongoose's default index build use `createIndex()`
+     * instead of `ensureIndex()` to avoid deprecation warnings from the MongoDB driver.
+     */
+    useCreateIndex?: boolean;
+
+    /**
+     * true by default. Set to `false` to make `findOneAndUpdate()` and `findOneAndRemove()`
+     * use native `findOneAndUpdate()` rather than `findAndModify()`.
+     */
+    useFindAndModify?: boolean;
+
+    /** false by default. Set to `true` to make all connections set the `useNewUrlParser` option by default */
+    useNewUrlParser?: boolean;
+
+    usePushEach?: boolean;
+
+    /** false by default. Set to `true` to make all connections set the `useUnifiedTopology` option by default */
+    useUnifiedTopology?: boolean;
+  }
+
   // eslint-disable-next-line @typescript-eslint/no-empty-interface
   interface ClientSession extends mongodb.ClientSession { }
 

From 2fe7c7dcb7cbe1fe9fb1b15ba4779d31aca0b7b2 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 20 Jul 2021 14:03:48 +0200
Subject: [PATCH 2229/2348] refactor(test): prefer explicitly asserting against
 error over success properties

---
 test/model.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/model.test.js b/test/model.test.js
index 80aac53a981..4e082c3e847 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -7567,8 +7567,8 @@ describe('Model', function() {
       return co(function*() {
         const user = yield User.create({ name: 'Hafez' });
 
-        const res = yield User.bulkSave([user]);
-        assert.ok(res.result.ok);
+        const err = yield User.bulkSave([user]).then(() => null, err => err);
+        assert.ok(err == null);
       });
     });
   });

From b0938789e5c56d3c45bc5eec9bc184e41229ab55 Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Tue, 20 Jul 2021 14:14:23 +0200
Subject: [PATCH 2230/2348] refactor(model): prefer explanatory code over
 comment

---
 lib/model.js | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index ee3fae6a1fe..32b73ac8632 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3730,13 +3730,14 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents, op
 
     const delta = document.$__delta();
 
-    if (document.isNew) {
-      // new document
+    const isANewDocument = document.isNew;
+    const isDocumentWithChanges = delta != null && !utils.isEmptyObject(delta[0]);
+
+    if (isANewDocument) {
       accumulator.push({
         insertOne: { document }
       });
-    } else if (delta != null && !utils.isEmptyObject(delta[0])) {
-      // document with changes
+    } else if (isDocumentWithChanges) {
       const where = document.$__where(delta[0]);
       const changes = delta[1];
 

From d107d1fdb8d0d0084521a81a76feb7c1dd94f9ab Mon Sep 17 00:00:00 2001
From: Hafez <a.hafez852@gmail.com>
Date: Wed, 21 Jul 2021 13:16:30 +0200
Subject: [PATCH 2231/2348] refactor(model): prefer early returns over else if

---
 lib/model.js | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 32b73ac8632..46709d041af 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3728,16 +3728,19 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents, op
       }
     }
 
-    const delta = document.$__delta();
-
     const isANewDocument = document.isNew;
-    const isDocumentWithChanges = delta != null && !utils.isEmptyObject(delta[0]);
-
     if (isANewDocument) {
       accumulator.push({
         insertOne: { document }
       });
-    } else if (isDocumentWithChanges) {
+
+      return accumulator;
+    }
+
+    const delta = document.$__delta();
+    const isDocumentWithChanges = delta != null && !utils.isEmptyObject(delta[0]);
+
+    if (isDocumentWithChanges) {
       const where = document.$__where(delta[0]);
       const changes = delta[1];
 
@@ -3751,6 +3754,8 @@ Model.buildBulkWriteOperations = function buildBulkWriteOperations(documents, op
           update: changes
         }
       });
+
+      return accumulator;
     }
 
     return accumulator;

From 8fb041a50caaa534d679c7a7ffa153b2e686239d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 25 Jul 2021 20:19:59 -0400
Subject: [PATCH 2232/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 0ba5e2f969f..44043867a5f 100644
--- a/index.pug
+++ b/index.pug
@@ -361,6 +361,9 @@ html(lang='en')
               <a rel="sponsored" href="https://www.bonusfinder.co.uk/">
                 <img class="sponsor" src="https://images.opencollective.com/bonusfinder-uk/ecdd3af/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://onlinecasinohex.nl/">
+                <img class="sponsor" src="https://images.opencollective.com/onlinecasinohex-nl/ed24082/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From ef1c65eb2a48f9b72f704856175b65da28ea5cb5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?D=C3=A1niel=20Juh=C3=A1sz?= <juhdanad@gmail.com>
Date: Wed, 28 Jul 2021 11:42:52 +0200
Subject: [PATCH 2233/2348] Make LeanDocument work on union types

This way, it respects the PopulatedDoc type:
it leaves the ObjectId as-is,
but changes the populated document to its lean version.
---
 index.d.ts                   | 15 ++++++++++-----
 test/typescript/main.test.js |  3 ++-
 test/typescript/populate.ts  | 21 ++++++++++++++++++---
 3 files changed, 30 insertions(+), 9 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4c66e4fac62..594c98ee484 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2438,13 +2438,18 @@ declare module 'mongoose' {
   type LeanArray<T extends unknown[]> = T extends unknown[][] ? LeanArray<T[number]>[] : LeanType<T[number]>[];
 
   export type _LeanDocument<T> = {
-    [K in keyof T]:
-    0 extends (1 & T[K]) ? T[K] : // any
-    T[K] extends unknown[] ? LeanArray<T[K]> : // Array
-    T[K] extends Document ? LeanDocument<T[K]> : // Subdocument
-    T[K];
+    [K in keyof T]: LeanDocumentElement<T[K]>;
   };
 
+  // Keep this a separate type, to ensure that T is a naked type.
+  // This way, the conditional type is distributive over union types.
+  // This is required for PopulatedDoc.
+  type LeanDocumentElement<T> =
+    0 extends (1 & T) ? T : // any
+    T extends unknown[] ? LeanArray<T> : // Array
+    T extends Document ? LeanDocument<T> : // Subdocument
+    T;
+
   export type LeanDocument<T> = Omit<_LeanDocument<T>, Exclude<keyof Document, '_id' | 'id' | '__v'> | '$isSingleNested'>;
 
   export type LeanDocumentOrArray<T> = 0 extends (1 & T) ? T :
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index 4905d579f68..da0e1afe237 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -198,7 +198,8 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 0);
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.includes('Property \'save\' does not exist'), errors[0].messageText);
   });
 
   it('generics', function() {
diff --git a/test/typescript/populate.ts b/test/typescript/populate.ts
index 5020e8660c8..6f4eee9d722 100644
--- a/test/typescript/populate.ts
+++ b/test/typescript/populate.ts
@@ -1,4 +1,6 @@
 import { Schema, model, Document, PopulatedDoc } from 'mongoose';
+// Use the mongodb ObjectId to make instanceof calls possible
+import { ObjectId } from "mongodb";
 
 interface Child {
   name: string;
@@ -8,7 +10,7 @@ const childSchema: Schema = new Schema({ name: String });
 const ChildModel = model<Child>('Child', childSchema);
 
 interface Parent {
-  child?: PopulatedDoc<Child & Document>,
+  child?: PopulatedDoc<Child & Document<ObjectId>>,
   name?: string
 }
 
@@ -17,8 +19,21 @@ const ParentModel = model<Parent>('Parent', new Schema({
   name: String
 }));
 
-ParentModel.findOne({}).populate('child').orFail().then((doc: Parent) => {
-  useChildDoc(doc.child);
+ParentModel.findOne({}).populate('child').orFail().then((doc: Parent & Document) => {
+  const child = doc.child;
+  if (child == null || child instanceof ObjectId) {
+    throw new Error('should be populated');
+  } else {
+    useChildDoc(child);
+  }
+  const lean = doc.toObject();
+  const leanChild = lean.child;
+  if (leanChild == null || leanChild instanceof ObjectId) {
+    throw new Error('should be populated');
+  } else {
+    const name = leanChild.name;
+    leanChild.save();
+  }
 });
 
 function useChildDoc(child: Child): void {

From 7dd2aaf92572d5d0e96f9bcb1af52972281f7402 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 11:44:09 -0400
Subject: [PATCH 2234/2348] test(document): repro #10449

---
 test/document.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/document.test.js b/test/document.test.js
index 48135a4ac2c..51b88f7f042 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10469,4 +10469,20 @@ describe('document', function() {
     }
   });
 
+  it('does not pull non-schema paths from parent documents into nested paths (gh-10449)', function() {
+    const schema = new Schema({
+      name: String,
+      nested: {
+        data: String
+      }
+    });
+    const Test = db.model('Test', schema);
+
+    return co(function*() {
+      const doc = new Test({});
+      doc.otherProp = 'test';
+
+      assert.ok(!doc.nested.otherProp);
+    });
+  });
 });

From 62b7b9c07ad3c763d5e42714ee149c28412db79e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 11:54:50 -0400
Subject: [PATCH 2235/2348] fix: avoid pulling non-schema paths from documents
 into nested paths

Re: #10449
---
 lib/helpers/document/compile.js | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/helpers/document/compile.js b/lib/helpers/document/compile.js
index 47e15f4d6cc..caa9c203b33 100644
--- a/lib/helpers/document/compile.js
+++ b/lib/helpers/document/compile.js
@@ -188,13 +188,7 @@ function getOwnPropertyDescriptors(object) {
   const result = {};
 
   Object.getOwnPropertyNames(object).forEach(function(key) {
-    result[key] = Object.getOwnPropertyDescriptor(object, key);
-    // Assume these are schema paths, ignore them re: #5470
-    if (result[key].get) {
-      delete result[key];
-      return;
-    }
-    result[key].enumerable = [
+    const skip = [
       'isNew',
       '$__',
       'errors',
@@ -205,6 +199,12 @@ function getOwnPropertyDescriptors(object) {
       '__index',
       '$isDocumentArrayElement'
     ].indexOf(key) === -1;
+    if (skip) {
+      return;
+    }
+
+    result[key] = Object.getOwnPropertyDescriptor(object, key);
+    result[key].enumerable = false;
   });
 
   return result;

From 4640beea9a5f628aab599a7126b11259a7335426 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 12:24:56 -0400
Subject: [PATCH 2236/2348] style: fix lint

---
 test/document.test.js | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index 51b88f7f042..e5e8e8d5f5e 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10478,11 +10478,9 @@ describe('document', function() {
     });
     const Test = db.model('Test', schema);
 
-    return co(function*() {
-      const doc = new Test({});
-      doc.otherProp = 'test';
+    const doc = new Test({});
+    doc.otherProp = 'test';
 
-      assert.ok(!doc.nested.otherProp);
-    });
+    assert.ok(!doc.nested.otherProp);
   });
 });

From 1589af28bd29bd74da38202b774a9cac104377d6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 12:26:37 -0400
Subject: [PATCH 2237/2348] fix(cursor): cap parallel batchSize for populate at
 5000

Fix #10449
Re: #9366
---
 lib/cursor/QueryCursor.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 9c016a2facb..f38229bd848 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -55,6 +55,9 @@ function QueryCursor(query, options) {
     if (this.options.batchSize) {
       this.options.cursor = options.cursor || {};
       this.options.cursor.batchSize = options.batchSize;
+
+      // Max out the number of documents we'll populate in parallel at 5000.
+      this.options._populateBatchSize = Math.min(this.options.batchSize, 5000);
     }
     model.collection.find(query._conditions, this.options, function(err, cursor) {
       if (_this._error) {
@@ -360,7 +363,7 @@ function _next(ctx, cb) {
         ctx.query._mongooseOptions);
       ctx._pop.__noPromise = true;
     }
-    if (ctx.query._mongooseOptions.populate && ctx.options.batchSize > 1) {
+    if (ctx.query._mongooseOptions.populate && ctx.options._populateBatchSize > 1) {
       if (ctx._batchDocs && ctx._batchDocs.length) {
         // Return a cached populated doc
         return _nextDoc(ctx, ctx._batchDocs.shift(), ctx._pop, callback);
@@ -418,7 +421,7 @@ function _onNext(error, doc) {
 
   this.ctx._batchDocs.push(doc);
 
-  if (this.ctx._batchDocs.length < this.ctx.options.batchSize) {
+  if (this.ctx._batchDocs.length < this.ctx.options._populateBatchSize) {
     this.ctx.cursor.next(_onNext.bind(this));
   } else {
     _populateBatch.call(this);

From 257adc46c1bf2a1ba6a40aaa03ed81e417392264 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 12:29:34 -0400
Subject: [PATCH 2238/2348] fix(update): apply timestamps to subdocs that would
 be newly created by `$setOnInsert`

Fix #10460
---
 lib/helpers/update/applyTimestampsToChildren.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/helpers/update/applyTimestampsToChildren.js b/lib/helpers/update/applyTimestampsToChildren.js
index 76bac6e6608..6186c3d4d92 100644
--- a/lib/helpers/update/applyTimestampsToChildren.js
+++ b/lib/helpers/update/applyTimestampsToChildren.js
@@ -30,6 +30,12 @@ function applyTimestampsToChildren(now, update, schema) {
         applyTimestampsToUpdateKey(schema, key, update.$set, now);
       }
     }
+    if (update.$setOnInsert != null) {
+      const keys = Object.keys(update.$setOnInsert);
+      for (const key of keys) {
+        applyTimestampsToUpdateKey(schema, key, update.$setOnInsert, now);
+      }
+    }
   }
 
   const updateKeys = Object.keys(update).filter(key => !key.startsWith('$'));

From fa4094ada68a8de846eac773024e266061a7f629 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 12:37:38 -0400
Subject: [PATCH 2239/2348] chore: peg optional-require to v1.0.x re:
 jchip/optional-require#6

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 81612d8d925..2b7ee537f84 100644
--- a/package.json
+++ b/package.json
@@ -28,6 +28,7 @@
     "mpath": "0.8.3",
     "mquery": "3.2.5",
     "ms": "2.1.2",
+    "optional-require": "1.0.x",
     "regexp-clone": "1.0.0",
     "safe-buffer": "5.2.1",
     "sift": "13.5.2",

From e2d94cb416b8c0cc9f8933de3ef5f6d622b4fac6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 14:15:38 -0400
Subject: [PATCH 2240/2348] docs(mongoose+connection): correct default value
 for bufferTimeoutMS

Fix #10476
---
 lib/connection.js | 2 +-
 lib/index.js      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/connection.js b/lib/connection.js
index d1292a72bc8..aeb923ef307 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -652,7 +652,7 @@ Connection.prototype.onOpen = function() {
  * @param {String} uri The URI to connect with.
  * @param {Object} [options] Passed on to http://mongodb.github.io/node-mongodb-native/2.2/api/MongoClient.html#connect
  * @param {Boolean} [options.bufferCommands=true] Mongoose specific option. Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection.
- * @param {Number} [options.bufferTimeoutMS=true] Mongoose specific option. If `bufferCommands` is true, Mongoose will throw an error after `bufferTimeoutMS` if the operation is still buffered.
+ * @param {Number} [options.bufferTimeoutMS=10000] Mongoose specific option. If `bufferCommands` is true, Mongoose will throw an error after `bufferTimeoutMS` if the operation is still buffered.
  * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.
diff --git a/lib/index.js b/lib/index.js
index ff42be3bebf..30c74ec3400 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -317,7 +317,7 @@ Mongoose.prototype.createConnection = function(uri, options, callback) {
  * @param {String} uri(s)
  * @param {Object} [options] passed down to the [MongoDB driver's `connect()` function](http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html), except for 4 mongoose-specific options explained below.
  * @param {Boolean} [options.bufferCommands=true] Mongoose specific option. Set to false to [disable buffering](http://mongoosejs.com/docs/faq.html#callback_never_executes) on all models associated with this connection.
- * @param {Number} [options.bufferTimeoutMS=true] Mongoose specific option. If `bufferCommands` is true, Mongoose will throw an error after `bufferTimeoutMS` if the operation is still buffered.
+ * @param {Number} [options.bufferTimeoutMS=10000] Mongoose specific option. If `bufferCommands` is true, Mongoose will throw an error after `bufferTimeoutMS` if the operation is still buffered.
  * @param {String} [options.dbName] The name of the database we want to use. If not provided, use database name from connection string.
  * @param {String} [options.user] username for authentication, equivalent to `options.auth.user`. Maintained for backwards compatibility.
  * @param {String} [options.pass] password for authentication, equivalent to `options.auth.password`. Maintained for backwards compatibility.

From 926533febce57a444aec6539e821c0fceb961864 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 15:09:13 -0400
Subject: [PATCH 2241/2348] test: repro #10485

---
 test/model.findOneAndUpdate.test.js | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/test/model.findOneAndUpdate.test.js b/test/model.findOneAndUpdate.test.js
index 93e732bb168..19bc3612fa2 100644
--- a/test/model.findOneAndUpdate.test.js
+++ b/test/model.findOneAndUpdate.test.js
@@ -2507,4 +2507,30 @@ describe('model: findOneAndUpdate:', function() {
       assert.equal(doc.a, 2);
     });
   });
+
+  it('supports overwriting nested map paths (gh-10485)', function() {
+    const child = new mongoose.Schema({
+      vals: {
+        type: mongoose.Schema.Types.Map,
+        of: String
+      }
+    });
+
+    const parent = new mongoose.Schema({
+      children: {
+        type: [child]
+      }
+    });
+    const Parent = db.model('Parent', parent);
+
+    return co(function*() {
+      const parent = yield Parent.create({
+        children: [{ vals: { github: 'hello', twitter: 'world' } }]
+      });
+
+      const res = yield Parent.findOneAndUpdate({ _id: parent._id, 'children.vals.github': { $exists: true } },
+        { $set: { 'children.$.vals': { telegram: 'hello' } } }, { new: true });
+      assert.deepEqual(res.toObject().children[0].vals, new Map([['telegram', 'hello']]));
+    });
+  });
 });

From b6beb3ee50fe049cd3ef516a0550bb1a05003511 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 15:09:24 -0400
Subject: [PATCH 2242/2348] fix(update): support overwriting nested map paths

Fix #10485
---
 lib/schema.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/schema.js b/lib/schema.js
index 8072ac453a6..e298742bec8 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -2036,7 +2036,7 @@ Schema.prototype._getSchema = function(path) {
           }
         } else if (foundschema.$isSchemaMap) {
           if (p + 1 >= parts.length) {
-            return foundschema.$__schemaType;
+            return foundschema;
           }
           const ret = search(parts.slice(p + 1), foundschema.$__schemaType.schema);
           return ret;

From 1be924defe8b4bcd2c05c8914b28db7af3db0156 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 15:13:51 -0400
Subject: [PATCH 2243/2348] style: fix lint

---
 test/typescript/populate.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/typescript/populate.ts b/test/typescript/populate.ts
index 6f4eee9d722..89d95ac6d96 100644
--- a/test/typescript/populate.ts
+++ b/test/typescript/populate.ts
@@ -1,6 +1,6 @@
 import { Schema, model, Document, PopulatedDoc } from 'mongoose';
 // Use the mongodb ObjectId to make instanceof calls possible
-import { ObjectId } from "mongodb";
+import { ObjectId } from 'mongodb';
 
 interface Child {
   name: string;

From 77930651c90b88a98527ee2cfea25e9e8ab31c07 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 15:29:42 -0400
Subject: [PATCH 2244/2348] test(map): repro #10486

---
 test/document.test.js | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/test/document.test.js b/test/document.test.js
index e5e8e8d5f5e..1026e6abd07 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -7159,11 +7159,13 @@ describe('document', function() {
     return event.validate();
   });
 
-  it('flattenMaps option for toObject() (gh-7274)', function() {
+  it('flattenMaps option for toObject() (gh-7274) (gh-10486)', function() {
+    const subSchema = new Schema({ name: String });
+
     let schema = new Schema({
       test: {
         type: Map,
-        of: String,
+        of: subSchema,
         default: new Map()
       }
     }, { versionKey: false });
@@ -7171,13 +7173,14 @@ describe('document', function() {
     let Test = db.model('Test', schema);
 
     let mapTest = new Test({});
-    mapTest.test.set('key1', 'value1');
-    assert.equal(mapTest.toObject({ flattenMaps: true }).test.key1, 'value1');
+    mapTest.test.set('key1', { name: 'value1' });
+    // getters: true for gh-10486
+    assert.equal(mapTest.toObject({ getters: true, flattenMaps: true }).test.key1.name, 'value1');
 
     schema = new Schema({
       test: {
         type: Map,
-        of: String,
+        of: subSchema,
         default: new Map()
       }
     }, { versionKey: false });
@@ -7187,10 +7190,8 @@ describe('document', function() {
     Test = db.model('Test', schema);
 
     mapTest = new Test({});
-    mapTest.test.set('key1', 'value1');
-    assert.equal(mapTest.toObject({}).test.key1, 'value1');
-
-    return Promise.resolve();
+    mapTest.test.set('key1', { name: 'value1' });
+    assert.equal(mapTest.toObject({}).test.key1.name, 'value1');
   });
 
   it('`collection` property with strict: false (gh-7276)', function() {

From 2066180c9dcde396c7ff1b208281b1bda4b9833e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 15:30:38 -0400
Subject: [PATCH 2245/2348] fix(map): correctly clone subdocs when calling
 `toObject()` on a map

Fix #10486
---
 lib/types/map.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/types/map.js b/lib/types/map.js
index 8d67324ea29..1cfcd06fef3 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -2,6 +2,7 @@
 
 const Mixed = require('../schema/mixed');
 const ObjectId = require('./objectid');
+const clone = require('../helpers/clone');
 const deepEqual = require('../utils').deepEqual;
 const get = require('../helpers/get');
 const handleSpreadDoc = require('../helpers/document/handleSpreadDoc');
@@ -133,7 +134,7 @@ class MongooseMap extends Map {
       const ret = {};
       const keys = this.keys();
       for (const key of keys) {
-        ret[key] = this.get(key);
+        ret[key] = clone(this.get(key));
       }
       return ret;
     }

From 060039de5cdb5cd7ccdb6662293b063e52617f16 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 16:59:17 -0400
Subject: [PATCH 2246/2348] fix(index.d.ts): improve autocomplete for `new
 Model()` by making `doc` an object with correct keys

Fix #10475
Re: #10343
Re: #10302
---
 index.d.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 066517b7bcb..9e0ad99ff39 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -750,12 +750,13 @@ declare module 'mongoose' {
     discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
   }
 
+  type AnyKeys<T> = Partial<{ [P in keyof T]: T[P] | any }>;
   interface AnyObject { [k: string]: any }
   type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document<any, any, T> & TMethods;
 
   export const Model: Model<any>;
   interface Model<T, TQueryHelpers = {}, TMethods = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
-    new(doc?: T | any): EnforceDocument<T, TMethods>;
+    new(doc?: AnyKeys<T> & AnyObject): EnforceDocument<T, TMethods>;
 
     aggregate<R = any>(pipeline?: any[]): Aggregate<Array<R>>;
     aggregate<R = any>(pipeline: any[], cb: Function): Promise<Array<R>>;

From 6b33a7b639ea8bdf321b804b61b3cb1cf3a0b23a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 17:12:00 -0400
Subject: [PATCH 2247/2348] chore: release 5.13.4

---
 History.md   | 13 +++++++++++++
 package.json |  2 +-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index d62dd16663f..2df0fb384b4 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,16 @@
+5.13.4 / 2021-07-28
+===================
+ * fix: avoid pulling non-schema paths from documents into nested paths #10449
+ * fix(update): support overwriting nested map paths #10485
+ * fix(update): apply timestamps to subdocs that would be newly created by `$setOnInsert` #10460
+ * fix(map): correctly clone subdocs when calling toObject() on a map #10486
+ * fix(cursor): cap parallel batchSize for populate at 5000 #10449
+ * fix(index.d.ts): improve autocomplete for new Model() by making `doc` an object with correct keys #10475
+ * fix(index.d.ts): add MongooseOptions interface #10471 [thiagokisaki](https://github.com/thiagokisaki)
+ * fix(index.d.ts): make LeanDocument work with PopulatedDoc #10494
+ * docs(mongoose+connection): correct default value for bufferTimeoutMS #10476
+ * chore: remove unnecessary 'eslint-disable' comments #10466 [thiagokisaki](https://github.com/thiagokisaki)
+
 5.13.3 / 2021-07-16
 ===================
  * fix(model): avoid throwing error when bulkSave() called on a document with no changes #10437
diff --git a/package.json b/package.json
index 2b7ee537f84..0329bcbe8d7 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.3",
+  "version": "5.13.4",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b82aa37566b2908d0b4c52dfb4891675c6c10f36 Mon Sep 17 00:00:00 2001
From: gfrancz <52467377+gfrancz@users.noreply.github.com>
Date: Wed, 28 Jul 2021 14:39:18 -0700
Subject: [PATCH 2248/2348] Update depopulate documentation for document.js

Currently the documentation indicates that if a path for depopulate(path) is not provided, then it's a no-op. This is absolutely not true -- in fact, all fields are depopulated. This change fixes the documentation issue.
---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 9172018ae51..ef31c2e5288 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -4146,7 +4146,7 @@ Document.prototype.populated = function(path, val, options) {
  *       console.log(doc.author); // '5144cf8050f071d979c118a7'
  *     })
  *
- * If the path was not populated, this is a no-op.
+ * If the path was not provided, then all populated fields are returned to their unpopulated state.
  *
  * @param {String} path
  * @return {Document} this

From 28b1aa33fd6c7ad302cf1cb574d548844335c158 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 28 Jul 2021 17:42:59 -0400
Subject: [PATCH 2249/2348] fix: get rid of hardcoding of @types/node re:
 DefinitelyTyped/DefinitelyTyped#54479

---
 package.json | 1 -
 1 file changed, 1 deletion(-)

diff --git a/package.json b/package.json
index 0329bcbe8d7..41e20fcca2d 100644
--- a/package.json
+++ b/package.json
@@ -20,7 +20,6 @@
   "license": "MIT",
   "dependencies": {
     "@types/mongodb": "^3.5.27",
-    "@types/node": "14.x || 15.x",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
     "mongodb": "3.6.10",

From ae819ccde9c9977cf3b628d18991c5b0bfb5c678 Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Thu, 29 Jul 2021 09:49:18 -0300
Subject: [PATCH 2250/2348] fix(index.d.ts): fix `debug` type in
 `MongooseOptions`

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 9e0ad99ff39..de06996f8f8 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -188,7 +188,7 @@ declare module 'mongoose' {
     debug?:
       | boolean
       | { color?: boolean; shell?: boolean }
-      | WritableStream
+      | stream.Writable
       | ((collectionName: string, methodName: string, ...methodArgs: any[]) => void);
 
     /** If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query */

From 9c41c194b459403c1e27d5c264d153054419f613 Mon Sep 17 00:00:00 2001
From: Andrei Alecu <andreialecu@users.noreply.github.com>
Date: Fri, 30 Jul 2021 10:40:22 +0300
Subject: [PATCH 2251/2348] perf: improve typescript type checking performance

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 9e0ad99ff39..a02a598e76f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2494,9 +2494,9 @@ declare module 'mongoose' {
     ? mongodb.Condition<T[P]>
     : mongodb.Condition<T[P] | string>;
   } &
-    mongodb.RootQuerySelector<T>;
+    mongodb.RootQuerySelector<DocumentDefinition<T>>;
 
-  export type FilterQuery<T> = _FilterQuery<DocumentDefinition<T>>;
+  export type FilterQuery<T> = _FilterQuery<T>;
 
   type NumericTypes = number | mongodb.Decimal128 | mongodb.Double | mongodb.Int32 | mongodb.Long;
 

From c36bd644ca33bef4bcc49ce59f046ad0f0a0fde4 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 30 Jul 2021 11:41:06 -0400
Subject: [PATCH 2252/2348] chore: release 5.13.5

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 2df0fb384b4..f0bb4529a18 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.13.5 / 2021-07-30
+===================
+ * perf(index.d.ts): improve typescript type checking performance #10515 [andreialecu](https://github.com/andreialecu)
+ * fix(index.d.ts): fix debug type in MongooseOptions #10510 [thiagokisaki](https://github.com/thiagokisaki)
+ * docs(api): clarify that `depopulate()` with no args depopulates all #10501 [gfrancz](https://github.com/gfrancz)
+
 5.13.4 / 2021-07-28
 ===================
  * fix: avoid pulling non-schema paths from documents into nested paths #10449
diff --git a/package.json b/package.json
index 41e20fcca2d..52c977cde8d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.4",
+  "version": "5.13.5",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 9b00c96d442565e99bb5313f2426cc81758bb804 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 2 Aug 2021 11:26:39 -0400
Subject: [PATCH 2253/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index 44043867a5f..e44b1b11e23 100644
--- a/index.pug
+++ b/index.pug
@@ -364,6 +364,9 @@ html(lang='en')
               <a rel="sponsored" href="https://onlinecasinohex.nl/">
                 <img class="sponsor" src="https://images.opencollective.com/onlinecasinohex-nl/ed24082/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://veikkausbonukset.com/">
+                <img class="sponsor" src="https://images.opencollective.com/vbonukset1/c39e354/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 47cba8e80e569e163a44073abe453afbba5c45ee Mon Sep 17 00:00:00 2001
From: Efe <48628713+Raader@users.noreply.github.com>
Date: Wed, 4 Aug 2021 01:34:56 +0300
Subject: [PATCH 2254/2348] update type declarations for index related fields
 in Schema

---
 index.d.ts | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index db22e85d056..f5c3df5dff0 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1231,6 +1231,8 @@ declare module 'mongoose' {
   type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
   type ErrorHandlingMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, err: NativeError, res: ResType, next: (err?: CallbackError) => void) => void;
+  
+  type Index = { [key: string]: boolean | number | string | Index }
 
   class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined, TInstanceMethods = ExtractMethods<M>> extends events.EventEmitter {
     /**
@@ -1257,14 +1259,15 @@ declare module 'mongoose' {
     /** Iterates the schemas paths similar to Array#forEach. */
     eachPath(fn: (path: string, type: SchemaType) => void): this;
 
+    
     /** Defines an index (most likely compound) for this schema. */
-    index(fields: any, options?: any): this;
+    index(fields: Index, options?: IndexOptions): this;
 
     /**
      * Returns a list of indexes that this schema declares, via `schema.index()`
      * or by `index: true` in a path's options.
      */
-    indexes(): Array<any>;
+    indexes(): Array<Index>;
 
     /** Gets a schema option. */
     get(path: string): any;

From 7a57544260dba948ca9cfa7d9f15a35c3ad7437d Mon Sep 17 00:00:00 2001
From: Fabian Pfannes <fp@maon.eu>
Date: Thu, 5 Aug 2021 21:37:20 +0200
Subject: [PATCH 2255/2348] bump mongodb to 3.6.11

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 52c977cde8d..f8ec94cdb69 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.10",
+    "mongodb": "3.6.11",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.3",
     "mquery": "3.2.5",

From 9a87c36a79e473b1574412b4dc98286ba87701a2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 5 Aug 2021 20:44:56 -0400
Subject: [PATCH 2256/2348] chore: update opencollective sponsors

---
 index.pug | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.pug b/index.pug
index e44b1b11e23..a41036fa2a2 100644
--- a/index.pug
+++ b/index.pug
@@ -367,6 +367,9 @@ html(lang='en')
               <a rel="sponsored" href="https://veikkausbonukset.com/">
                 <img class="sponsor" src="https://images.opencollective.com/vbonukset1/c39e354/logo/256.png" style="height: 100px">
               </a>
+              <a rel="sponsored" href="https://casinoenlineahex.com/">
+                <img class="sponsor" src="https://images.opencollective.com/casinoenlinea-hex/b917401/logo/256.png" style="height: 100px">
+              </a>
             </div>
           </div>
 

From 4c8847e8d0ebcc8e3fe120426f1ab45bba7236ec Mon Sep 17 00:00:00 2001
From: GCastilho <castilho.gabriel14@gmail.com>
Date: Thu, 5 Aug 2021 22:35:16 -0300
Subject: [PATCH 2257/2348] Fixed incorrect type definition for Query's .map
 function

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index db22e85d056..fbe6cda526a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2290,7 +2290,7 @@ declare module 'mongoose' {
      * Runs a function `fn` and treats the return value of `fn` as the new value
      * for the query to resolve to.
      */
-    map<MappedType>(fn: (doc: DocType) => MappedType): QueryWithHelpers<ResultType extends unknown[] ? MappedType[] : MappedType, DocType, THelpers, RawDocType>;
+    map<MappedType>(fn: (doc: ResultType) => MappedType): QueryWithHelpers<MappedType, DocType, THelpers, RawDocType>;
 
     /** Specifies an `$maxDistance` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     maxDistance(val: number): this;

From 0f8903d4d432a7b4cdd5f2e28d46b6ac256de7fd Mon Sep 17 00:00:00 2001
From: Shahriar Shojib <shahriar_shojib@hotmail.com>
Date: Fri, 6 Aug 2021 09:27:09 +0600
Subject: [PATCH 2258/2348] updated array push type definition

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index db22e85d056..9fa7ac30869 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1970,10 +1970,10 @@ declare module 'mongoose' {
       isMongooseArray: true;
 
       /** Pushes items to the array non-atomically. */
-      nonAtomicPush(...args: any[]): number;
+      nonAtomicPush(...args: T[]): number;
 
       /** Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking. */
-      push(...args: any[]): number;
+      push(...args: T[]): number;
 
       /**
        * Pulls items from the array atomically. Equality is determined by casting

From f64f65196494ad241c1d050712dbd869bd6f6051 Mon Sep 17 00:00:00 2001
From: Shahriar Shojib <shahriar_shojib@hotmail.com>
Date: Fri, 6 Aug 2021 09:45:56 +0600
Subject: [PATCH 2259/2348] updated definition for docArray

---
 index.d.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index 9fa7ac30869..a9be656c66e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2022,6 +2022,8 @@ declare module 'mongoose' {
 
       /** Searches array items for the first document with a matching _id. */
       id(id: any): T | null;
+
+      push(...args: any[]): number;
     }
 
     class EmbeddedDocument extends Document {

From b091ce9471093702c372579c5a4255113e03a924 Mon Sep 17 00:00:00 2001
From: Shahriar Shojib <shahriar_shojib@hotmail.com>
Date: Fri, 6 Aug 2021 10:05:47 +0600
Subject: [PATCH 2260/2348] added types for DocumentArray push

---
 index.d.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index a9be656c66e..c8bafd5382a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1957,6 +1957,7 @@ declare module 'mongoose' {
   }
 
   namespace Types {
+	type OmitDocumentTypes<T> = T extends Document ? Omit<T, keyof Document> : T
     class Array<T> extends global.Array<T> {
       /** Pops the array atomically at most one time per document `save()`. */
       $pop(): T;
@@ -2023,7 +2024,7 @@ declare module 'mongoose' {
       /** Searches array items for the first document with a matching _id. */
       id(id: any): T | null;
 
-      push(...args: any[]): number;
+      push(...args: Omit<T, keyof Document>[]): number;
     }
 
     class EmbeddedDocument extends Document {

From 8426d394245fa411f0e2c765d0b9c2db31c7e969 Mon Sep 17 00:00:00 2001
From: bvgusak <bvgusak@gmail.com>
Date: Fri, 6 Aug 2021 00:19:06 -0400
Subject: [PATCH 2261/2348] fix(index.d.ts): add missing type for diffIndexes

---
 index.d.ts | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index db22e85d056..1eb1ec3be18 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -754,6 +754,13 @@ declare module 'mongoose' {
   interface AnyObject { [k: string]: any }
   type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document<any, any, T> & TMethods;
 
+  interface IndexesDiff {
+    /** Indexes that would be created in mongodb. */
+    toCreate: Array<any>
+    /** Indexes that would be dropped in mongodb. */
+    toDrop: Array<any>
+  }
+
   export const Model: Model<any>;
   interface Model<T, TQueryHelpers = {}, TMethods = {}> extends NodeJS.EventEmitter, AcceptsDiscriminator {
     new(doc?: AnyKeys<T> & AnyObject): EnforceDocument<T, TMethods>;
@@ -912,6 +919,14 @@ declare module 'mongoose' {
     syncIndexes(options?: Record<string, unknown>): Promise<Array<string>>;
     syncIndexes(options: Record<string, unknown> | null, callback: (err: CallbackError, dropped: Array<string>) => void): void;
 
+    /**
+     * Does a dry-run of Model.syncIndexes(), meaning that
+     * the result of this function would be the result of
+     * Model.syncIndexes().
+     */
+    diffIndexes(options?: Record<string, unknown>): Promise<IndexesDiff>
+    diffIndexes(options: Record<string, unknown> | null, callback: (err: CallbackError, diff: IndexesDiff) => void): void
+
     /**
      * Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
      * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),

From 9cb7b1d10c07d2a0be44f41236a1b89c0238ebfe Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Fri, 6 Aug 2021 22:13:55 -0300
Subject: [PATCH 2262/2348] refactor(index.d.ts): add `Callback` type to avoid
 code repetition

---
 index.d.ts | 228 +++++++++++++++++++++++++++--------------------------
 1 file changed, 115 insertions(+), 113 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index db22e85d056..ee88924b407 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -64,8 +64,8 @@ declare module 'mongoose' {
   export const STATES: typeof ConnectionStates;
 
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
-  export function connect(uri: string, options: ConnectOptions, callback: (err: CallbackError) => void): void;
-  export function connect(uri: string, callback: (err: CallbackError) => void): void;
+  export function connect(uri: string, options: ConnectOptions, callback: Callback): void;
+  export function connect(uri: string, callback: Callback): void;
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
 
   /** The Mongoose module's default connection. Equivalent to `mongoose.connections[0]`, see [`connections`](#mongoose_Mongoose-connections). */
@@ -79,7 +79,7 @@ declare module 'mongoose' {
   /** Creates a Connection instance. */
   export function createConnection(uri: string, options?: ConnectOptions): Connection & Promise<Connection>;
   export function createConnection(): Connection;
-  export function createConnection(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn: Connection) => void): void;
+  export function createConnection(uri: string, options: ConnectOptions, callback: Callback<Connection>): void;
 
   /**
    * Removes the model named `name` from the default connection, if it exists.
@@ -89,7 +89,7 @@ declare module 'mongoose' {
   export function deleteModel(name: string | RegExp): typeof mongoose;
 
   export function disconnect(): Promise<void>;
-  export function disconnect(cb: (err: CallbackError) => void): void;
+  export function disconnect(cb: Callback): void;
 
   /** Gets mongoose options */
   export function get<K extends keyof MongooseOptions>(key: K): MongooseOptions[K];
@@ -136,7 +136,7 @@ declare module 'mongoose' {
    * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
    */
   export function startSession(options?: mongodb.SessionOptions): Promise<mongodb.ClientSession>;
-  export function startSession(options: mongodb.SessionOptions, cb: (err: CallbackError, session: mongodb.ClientSession) => void): void;
+  export function startSession(options: mongodb.SessionOptions, cb: Callback<mongodb.ClientSession>): void;
 
   /** The Mongoose version */
   export const version: string;
@@ -298,8 +298,8 @@ declare module 'mongoose' {
 
   class Connection extends events.EventEmitter {
     /** Closes the connection */
-    close(callback: (err: CallbackError) => void): void;
-    close(force: boolean, callback: (err: CallbackError) => void): void;
+    close(callback: Callback): void;
+    close(force: boolean, callback: Callback): void;
     close(force?: boolean): Promise<void>;
 
     /** Retrieves a collection, creating it if not cached. */
@@ -320,8 +320,8 @@ declare module 'mongoose' {
      * and [views](https://docs.mongodb.com/manual/core/views/) from mongoose.
      */
     createCollection<T = any>(name: string, options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
-    createCollection<T = any>(name: string, cb: (err: CallbackError, collection: mongodb.Collection<T>) => void): void;
-    createCollection<T = any>(name: string, options: mongodb.CollectionCreateOptions, cb?: (err: CallbackError, collection: mongodb.Collection) => void): Promise<mongodb.Collection<T>>;
+    createCollection<T = any>(name: string, cb: Callback<mongodb.Collection<T>>): void;
+    createCollection<T = any>(name: string, options: mongodb.CollectionCreateOptions, cb?: Callback<mongodb.Collection>): Promise<mongodb.Collection<T>>;
 
     /**
      * Removes the model named `name` from this connection, if it exists. You can
@@ -335,14 +335,14 @@ declare module 'mongoose' {
      * all documents and indexes.
      */
     dropCollection(collection: string): Promise<void>;
-    dropCollection(collection: string, cb: (err: CallbackError) => void): void;
+    dropCollection(collection: string, cb: Callback): void;
 
     /**
      * Helper for `dropDatabase()`. Deletes the given database, including all
      * collections, documents, and indexes.
      */
     dropDatabase(): Promise<void>;
-    dropDatabase(cb: (err: CallbackError) => void): void;
+    dropDatabase(cb: Callback): void;
 
     /** Gets the value of the option `key`. Equivalent to `conn.options[key]` */
     get(key: string): any;
@@ -389,8 +389,8 @@ declare module 'mongoose' {
 
     /** Opens the connection with a URI using `MongoClient.connect()`. */
     openUri(uri: string, options?: ConnectOptions): Promise<Connection>;
-    openUri(uri: string, callback: (err: CallbackError, conn?: Connection) => void): Connection;
-    openUri(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn?: Connection) => void): Connection;
+    openUri(uri: string, callback: Callback<Connection>): Connection;
+    openUri(uri: string, options: ConnectOptions, callback: Callback<Connection>): Connection;
 
     /** The password specified in the URI */
     pass: string;
@@ -433,7 +433,7 @@ declare module 'mongoose' {
      * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
      */
     startSession(options?: mongodb.SessionOptions): Promise<mongodb.ClientSession>;
-    startSession(options: mongodb.SessionOptions, cb: (err: CallbackError, session: mongodb.ClientSession) => void): void;
+    startSession(options: mongodb.SessionOptions, cb: Callback<mongodb.ClientSession>): void;
 
     /**
      * _Requires MongoDB >= 3.6.0._ Executes the wrapped async function
@@ -572,13 +572,13 @@ declare module 'mongoose' {
 
     /** Removes this document from the db. */
     delete(options?: QueryOptions): QueryWithHelpers<any, this, TQueryHelpers>;
-    delete(options: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
-    delete(cb: (err: CallbackError, res: any) => void): void;
+    delete(options: QueryOptions, cb?: Callback): void;
+    delete(cb: Callback): void;
 
     /** Removes this document from the db. */
     deleteOne(options?: QueryOptions): QueryWithHelpers<any, this, TQueryHelpers>;
-    deleteOne(options: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
-    deleteOne(cb: (err: CallbackError, res: any) => void): void;
+    deleteOne(options: QueryOptions, cb?: Callback): void;
+    deleteOne(cb: Callback): void;
 
     /** Takes a populated field and returns it to its unpopulated state. */
     depopulate(path: string): this;
@@ -604,7 +604,7 @@ declare module 'mongoose' {
 
     /** Explicitly executes population and returns a promise. Useful for promises integration. */
     execPopulate(): Promise<this>;
-    execPopulate(callback: (err: CallbackError, res: this) => void): void;
+    execPopulate(callback: Callback<this>): void;
 
     /** Returns the value of a path. */
     get(path: string, type?: any, options?: any): any;
@@ -626,7 +626,7 @@ declare module 'mongoose' {
      * Called internally after a document is returned from mongodb. Normally,
      * you do **not** need to call this function on your own.
      */
-    init(obj: any, opts?: any, cb?: (err: CallbackError, doc: this) => void): this;
+    init(obj: any, opts?: any, cb?: Callback<this>): this;
 
     /** Marks a path as invalid, causing validation to fail. */
     invalidate(path: string, errorMsg: string | NativeError, value?: any, kind?: string): NativeError | null;
@@ -682,25 +682,25 @@ declare module 'mongoose' {
      * If you want to use promises instead, use this function with
      * [`execPopulate()`](#document_Document-execPopulate).
      */
-    populate(path: string, callback?: (err: CallbackError, res: this) => void): this;
-    populate(path: string, names: string, callback?: (err: CallbackError, res: this) => void): this;
-    populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: (err: CallbackError, res: this) => void): this;
+    populate(path: string, callback?: Callback<this>): this;
+    populate(path: string, names: string, callback?: Callback<this>): this;
+    populate(opts: PopulateOptions | Array<PopulateOptions>, callback?: Callback<this>): this;
 
     /** Gets _id(s) used during population of the given `path`. If the path was not populated, returns `undefined`. */
     populated(path: string): any;
 
     /** Removes this document from the db. */
     remove(options?: QueryOptions): Promise<this>;
-    remove(options?: QueryOptions, cb?: (err: CallbackError, res: any) => void): void;
+    remove(options?: QueryOptions, cb?: Callback): void;
 
     /** Sends a replaceOne command with this document `_id` as the query selector. */
-    replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
-    replaceOne(replacement?: Object, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
+    replaceOne(replacement?: DocumentDefinition<this>, options?: QueryOptions | null, callback?: Callback): Query<any, this>;
+    replaceOne(replacement?: Object, options?: QueryOptions | null, callback?: Callback): Query<any, this>;
 
     /** Saves this document by inserting a new document into the database if [document.isNew](/docs/api.html#document_Document-isNew) is `true`, or sends an [updateOne](/docs/api.html#document_Document-updateOne) operation with just the modified paths if `isNew` is `false`. */
     save(options?: SaveOptions): Promise<this>;
-    save(options?: SaveOptions, fn?: (err: CallbackError, doc: this) => void): void;
-    save(fn?: (err: CallbackError, doc: this) => void): void;
+    save(options?: SaveOptions, fn?: Callback<this>): void;
+    save(fn?: Callback<this>): void;
 
     /** The document's schema. */
     schema: Schema;
@@ -722,17 +722,17 @@ declare module 'mongoose' {
     unmarkModified(path: string): void;
 
     /** Sends an update command with this document `_id` as the query selector. */
-    update(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
+    update(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback): Query<any, this>;
 
     /** Sends an updateOne command with this document `_id` as the query selector. */
-    updateOne(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): Query<any, this>;
+    updateOne(update?: UpdateQuery<this> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback): Query<any, this>;
 
     /** Executes registered validation rules for this document. */
     validate(options:{ pathsToSkip?: pathsToSkip }): Promise<void>;
     validate(pathsToValidate?: pathsToValidate, options?: any): Promise<void>;
-    validate(callback: (err: CallbackError) => void): void;
-    validate(pathsToValidate: pathsToValidate, callback: (err: CallbackError) => void): void;
-    validate(pathsToValidate: pathsToValidate, options: any, callback: (err: CallbackError) => void): void;
+    validate(callback: Callback): void;
+    validate(pathsToValidate: pathsToValidate, callback: Callback): void;
+    validate(pathsToValidate: pathsToValidate, options: any, callback: Callback): void;
 
     /** Executes registered validation rules (skipping asynchronous validators) for this document. */
     validateSync(options:{pathsToSkip?: pathsToSkip, [k:string]: any }): Error.ValidationError | null;
@@ -778,29 +778,29 @@ declare module 'mongoose' {
      * trip to MongoDB.
      */
     bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions): Promise<mongodb.BulkWriteOpResultObject>;
-    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: (err: CallbackError, res: mongodb.BulkWriteOpResultObject) => void): void;
+    bulkWrite(writes: Array<any>, options?: mongodb.CollectionBulkWriteOptions, cb?: Callback<mongodb.BulkWriteOpResultObject>): void;
 
     /** Collection the model uses. */
     collection: Collection;
 
     /** Creates a `count` query: counts the number of documents that match `filter`. */
-    count(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    count(filter: FilterQuery<T>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    count(callback?: Callback<number>): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    count(filter: FilterQuery<T>, callback?: Callback<number>): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `countDocuments` query: counts the number of documents that match `filter`. */
-    countDocuments(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    countDocuments(filter: FilterQuery<T>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    countDocuments(callback?: Callback<number>): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    countDocuments(filter: FilterQuery<T>, callback?: Callback<number>): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a new document or documents */
     create(docs: (T | DocumentDefinition<T> | AnyObject)[], options?: SaveOptions): Promise<EnforceDocument<T, TMethods>[]>;
-    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): void;
+    create(docs: (T | DocumentDefinition<T> | AnyObject)[], callback: Callback<EnforceDocument<T, TMethods>[]>): void;
     create(doc: T | DocumentDefinition<T> | AnyObject): Promise<EnforceDocument<T, TMethods>>;
-    create(doc: T | DocumentDefinition<T> | AnyObject, callback: (err: CallbackError, doc: EnforceDocument<T, TMethods>) => void): void;
+    create(doc: T | DocumentDefinition<T> | AnyObject, callback: Callback<EnforceDocument<T, TMethods>>): void;
     create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], options?: SaveOptions): Promise<EnforceDocument<T, TMethods>[]>;
-    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(docs: DocContents[], callback: Callback<EnforceDocument<T, TMethods>[]>): void;
     create<DocContents = T | DocumentDefinition<T>>(doc: DocContents): Promise<EnforceDocument<T, TMethods>>;
     create<DocContents = T | DocumentDefinition<T>>(...docs: DocContents[]): Promise<EnforceDocument<T, TMethods>[]>;
-    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: (err: CallbackError, doc: EnforceDocument<T, TMethods>) => void): void;
+    create<DocContents = T | DocumentDefinition<T>>(doc: DocContents, callback: Callback<EnforceDocument<T, TMethods>>): void;
 
     /**
      * Create the collection for this model. By default, if no indexes are specified,
@@ -808,14 +808,14 @@ declare module 'mongoose' {
      * created. Use this method to create the collection explicitly.
      */
     createCollection(options?: mongodb.CollectionCreateOptions): Promise<mongodb.Collection<T>>;
-    createCollection(options: mongodb.CollectionCreateOptions | null, callback: (err: CallbackError, collection: mongodb.Collection<T>) => void): void;
+    createCollection(options: mongodb.CollectionCreateOptions | null, callback: Callback<mongodb.Collection<T>>): void;
 
     /**
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
      * function.
      */
-    createIndexes(callback?: (err: CallbackError) => void): Promise<void>;
-    createIndexes(options?: any, callback?: (err: CallbackError) => void): Promise<void>;
+    createIndexes(callback?: Callback): Promise<void>;
+    createIndexes(options?: any, callback?: Callback): Promise<void>;
 
     /** Connection the model uses. */
     db: Connection;
@@ -825,25 +825,25 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteMany(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteMany(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(filter: FilterQuery<T>, callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteOne(filter: FilterQuery<T>, callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteOne(callback: (err: CallbackError) => void): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(filter: FilterQuery<T>, callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
      */
-    ensureIndexes(callback?: (err: CallbackError) => void): Promise<void>;
-    ensureIndexes(options?: any, callback?: (err: CallbackError) => void): Promise<void>;
+    ensureIndexes(callback?: Callback): Promise<void>;
+    ensureIndexes(options?: any, callback?: Callback): Promise<void>;
 
     /**
      * Event emitter that reports any errors that occurred. Useful for global error
@@ -856,10 +856,10 @@ declare module 'mongoose' {
      * equivalent to `findOne({ _id: id })`. If you want to query by a document's
      * `_id`, use `findById()` instead of `findOne()`.
      */
-    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findById(id: any, projection?: any | null, options?: QueryOptions | null, callback?: Callback<EnforceDocument<T, TMethods> | null>): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Finds one document. */
-    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOne(filter?: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: Callback<EnforceDocument<T, TMethods> | null>): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Shortcut for creating a new Document from existing raw data, pre-saved in the DB.
@@ -875,15 +875,15 @@ declare module 'mongoose' {
      * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
      * don't need to call it.
      */
-    init(callback?: (err: CallbackError) => void): Promise<EnforceDocument<T, TMethods>>;
+    init(callback?: Callback): Promise<EnforceDocument<T, TMethods>>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
     insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions): Promise<Array<EnforceDocument<T, TMethods>>>;
     insertMany(doc: T | DocumentDefinition<T> | AnyObject, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
     insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions): Promise<EnforceDocument<T, TMethods>>;
-    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: (err: CallbackError, res: EnforceDocument<T, TMethods> | InsertManyResult) => void): void;
-    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>> | InsertManyResult) => void): void;
+    insertMany(doc: T | DocumentDefinition<T> | AnyObject, options?: InsertManyOptions, callback?: Callback<EnforceDocument<T, TMethods> | InsertManyResult>): void;
+    insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options?: InsertManyOptions, callback?: Callback<Array<EnforceDocument<T, TMethods>> | InsertManyResult>): void;
 
     /**
      * Lists the indexes currently defined in MongoDB. This may or may not be
@@ -891,7 +891,7 @@ declare module 'mongoose' {
      * use the [`autoIndex` option](/docs/guide.html#autoIndex) and if you
      * build indexes manually.
      */
-    listIndexes(callback: (err: CallbackError, res: Array<any>) => void): void;
+    listIndexes(callback: Callback<Array<any>>): void;
     listIndexes(): Promise<Array<any>>;
 
     /** The name of the model */
@@ -899,9 +899,9 @@ declare module 'mongoose' {
 
     /** Populates document references. */
     populate(docs: Array<any>, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: CallbackError, res: (EnforceDocument<T, TMethods>)[]) => void): Promise<Array<EnforceDocument<T, TMethods>>>;
+      callback?: Callback<(EnforceDocument<T, TMethods>)[]>): Promise<Array<EnforceDocument<T, TMethods>>>;
     populate(doc: any, options: PopulateOptions | Array<PopulateOptions> | string,
-      callback?: (err: CallbackError, res: EnforceDocument<T, TMethods>) => void): Promise<EnforceDocument<T, TMethods>>;
+      callback?: Callback<EnforceDocument<T, TMethods>>): Promise<EnforceDocument<T, TMethods>>;
 
     /**
      * Makes the indexes in MongoDB match the indexes defined in this model's
@@ -910,19 +910,19 @@ declare module 'mongoose' {
      * are in your schema but not in MongoDB.
      */
     syncIndexes(options?: Record<string, unknown>): Promise<Array<string>>;
-    syncIndexes(options: Record<string, unknown> | null, callback: (err: CallbackError, dropped: Array<string>) => void): void;
+    syncIndexes(options: Record<string, unknown> | null, callback: Callback<Array<string>>): void;
 
     /**
      * Starts a [MongoDB session](https://docs.mongodb.com/manual/release-notes/3.6/#client-sessions)
      * for benefits like causal consistency, [retryable writes](https://docs.mongodb.com/manual/core/retryable-writes/),
      * and [transactions](http://thecodebarbarian.com/a-node-js-perspective-on-mongodb-4-transactions.html).
      * */
-    startSession(options?: mongodb.SessionOptions, cb?: (err: CallbackError, session: mongodb.ClientSession) => void): Promise<mongodb.ClientSession>;
+    startSession(options?: mongodb.SessionOptions, cb?: Callback<mongodb.ClientSession>): Promise<mongodb.ClientSession>;
 
     /** Casts and validates the given object against this model's schema, passing the given `context` to custom validators. */
-    validate(callback?: (err: CallbackError) => void): Promise<void>;
-    validate(optional: any, callback?: (err: CallbackError) => void): Promise<void>;
-    validate(optional: any, pathsToValidate: string[], callback?: (err: CallbackError) => void): Promise<void>;
+    validate(callback?: Callback): Promise<void>;
+    validate(optional: any, callback?: Callback): Promise<void>;
+    validate(optional: any, pathsToValidate: string[], callback?: Callback): Promise<void>;
 
     /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
     watch(pipeline?: Array<Record<string, unknown>>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
@@ -937,22 +937,22 @@ declare module 'mongoose' {
     translateAliases(raw: any): any;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<T>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    distinct(field: string, filter?: FilterQuery<T>, callback?: Callback<number>): QueryWithHelpers<Array<any>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: Callback<number>): QueryWithHelpers<number, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Returns true if at least one document exists in the database that matches
      * the given `filter`, and false otherwise.
      */
     exists(filter: FilterQuery<T>): Promise<boolean>;
-    exists(filter: FilterQuery<T>, callback: (err: CallbackError, res: boolean) => void): void;
+    exists(filter: FilterQuery<T>, callback: Callback<boolean>): void;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    find(filter: FilterQuery<T>, callback?: (err: CallbackError, docs: T[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: EnforceDocument<T, TMethods>[]) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(callback?: Callback<EnforceDocument<T, TMethods>[]>): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(filter: FilterQuery<T>, callback?: Callback<T[]>): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    find(filter: FilterQuery<T>, projection?: any | null, options?: QueryOptions | null, callback?: Callback<EnforceDocument<T, TMethods>[]>): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findByIdAndDelete` query, filtering by the given `_id`. */
     findByIdAndDelete(id?: mongodb.ObjectId | any, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
@@ -981,19 +981,19 @@ declare module 'mongoose' {
     findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
     findOneAndUpdate(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
-    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: (err: CallbackError, res: Array<EnforceDocument<T, TMethods>>) => void): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    geoSearch(filter?: FilterQuery<T>, options?: GeoSearchOptions, callback?: Callback<Array<EnforceDocument<T, TMethods>>>): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Executes a mapReduce command. */
     mapReduce<Key, Value>(
       o: MapReduceOptions<T, Key, Value>,
-      callback?: (err: CallbackError, res: any) => void
+      callback?: Callback
     ): Promise<any>;
 
-    remove(filter?: any, callback?: (err: CallbackError) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    remove(filter?: any, callback?: Callback): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
-    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    replaceOne(filter?: FilterQuery<T>, replacement?: Object, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Schema the model uses. */
     schema: Schema;
@@ -1002,13 +1002,13 @@ declare module 'mongoose' {
      * @deprecated use `updateOne` or `updateMany` instead.
      * Creates a `update` query: updates one or many documents that match `filter` with `update`, based on the `multi` option.
      */
-    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    update(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `updateMany` query: updates all documents that match `filter` with `update`. */
-    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    updateMany(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `updateOne` query: updates the first document that matches `filter` with `update`. */
-    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    updateOne(filter?: FilterQuery<T>, update?: UpdateQuery<T> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<UpdateWriteOpResult, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a Query, applies the passed conditions, and returns the Query. */
     where(path: string, val?: any): QueryWithHelpers<Array<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
@@ -2089,9 +2089,9 @@ declare module 'mongoose' {
 
     /** Executes the query */
     exec(): Promise<ResultType>;
-    exec(callback?: (err: CallbackError, res: ResultType) => void): void;
+    exec(callback?: Callback<ResultType>): void;
     // @todo: this doesn't seem right
-    exec(callback?: (err: CallbackError, result: ResultType) => void): Promise<ResultType> | any;
+    exec(callback?: Callback<ResultType>): Promise<ResultType> | any;
 
     $where(argument: string | Function): QueryWithHelpers<DocType[], DocType, THelpers, RawDocType>;
 
@@ -2136,12 +2136,12 @@ declare module 'mongoose' {
     comment(val: string): this;
 
     /** Specifies this query as a `count` query. */
-    count(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
-    count(criteria: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    count(callback?: Callback<number>): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    count(criteria: FilterQuery<DocType>, callback?: Callback<number>): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /** Specifies this query as a `countDocuments` query. */
-    countDocuments(callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
-    countDocuments(criteria: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    countDocuments(callback?: Callback<number>): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    countDocuments(criteria: FilterQuery<DocType>, callback?: Callback<number>): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /**
      * Returns a wrapper around a [mongodb driver cursor](http://mongodb.github.io/node-mongodb-native/2.1/api/Cursor.html).
@@ -2154,21 +2154,21 @@ declare module 'mongoose' {
      * remove, except it deletes _every_ document that matches `filter` in the
      * collection, regardless of the value of `single`.
      */
-    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
-    deleteMany(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
-    deleteMany(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteMany(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteMany(filter: FilterQuery<DocType>, callback: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteMany(callback: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as a `deleteOne()` operation. Works like
      * remove, except it deletes at most one document regardless of the `single`
      * option.
      */
-    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
-    deleteOne(filter: FilterQuery<DocType>, callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
-    deleteOne(callback: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteOne(filter?: FilterQuery<DocType>, options?: QueryOptions, callback?: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteOne(filter: FilterQuery<DocType>, callback: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    deleteOne(callback: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /** Creates a `distinct` query: returns the distinct values of the given `field` that match `filter`. */
-    distinct(field: string, filter?: FilterQuery<DocType>, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<Array<any>, DocType, THelpers, RawDocType>;
+    distinct(field: string, filter?: FilterQuery<DocType>, callback?: Callback<number>): QueryWithHelpers<Array<any>, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$elemMatch` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     elemMatch(val: Function | any): this;
@@ -2185,7 +2185,7 @@ declare module 'mongoose' {
     equals(val: any): this;
 
     /** Creates a `estimatedDocumentCount` query: counts the number of documents in the collection. */
-    estimatedDocumentCount(options?: QueryOptions, callback?: (err: CallbackError, count: number) => void): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
+    estimatedDocumentCount(options?: QueryOptions, callback?: Callback<number>): QueryWithHelpers<number, DocType, THelpers, RawDocType>;
 
     /** Specifies a `$exists` query condition. When called with one argument, the most recent path passed to `where()` is used. */
     exists(val: boolean): this;
@@ -2200,12 +2200,12 @@ declare module 'mongoose' {
     explain(verbose?: string): this;
 
     /** Creates a `find` query: gets a list of documents that match `filter`. */
-    find(callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
-    find(filter: FilterQuery<DocType>, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
-    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, docs: DocType[]) => void): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(callback?: Callback<DocType[]>): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(filter: FilterQuery<DocType>, callback?: Callback<DocType[]>): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
+    find(filter: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: Callback<DocType[]>): QueryWithHelpers<Array<DocType>, DocType, THelpers, RawDocType>;
 
     /** Declares the query a findOne operation. When executed, the first found document is passed to the callback. */
-    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
+    findOne(filter?: FilterQuery<DocType>, projection?: any | null, options?: QueryOptions | null, callback?: Callback<DocType | null>): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
 
     /** Creates a `findOneAndDelete` query: atomically finds the given document, deletes it, and returns the document as it was before deletion. */
     findOneAndDelete(filter?: FilterQuery<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: DocType | null, res: any) => void): QueryWithHelpers<DocType | null, DocType, THelpers, RawDocType>;
@@ -2370,15 +2370,15 @@ declare module 'mongoose' {
      * deprecated, you should use [`deleteOne()`](#query_Query-deleteOne)
      * or [`deleteMany()`](#query_Query-deleteMany) instead.
      */
-    remove(filter?: FilterQuery<DocType>, callback?: (err: CallbackError, res: mongodb.WriteOpResult['result']) => void): QueryWithHelpers<mongodb.WriteOpResult['result'], DocType, THelpers, RawDocType>;
+    remove(filter?: FilterQuery<DocType>, callback?: Callback<mongodb.WriteOpResult['result']>): QueryWithHelpers<mongodb.WriteOpResult['result'], DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as a replaceOne() operation. Same as
      * `update()`, except MongoDB will replace the existing document and will
      * not accept any [atomic](https://docs.mongodb.com/manual/tutorial/model-data-for-atomic-operations/#pattern) operators (`$set`, etc.)
      */
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
-    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: (err: CallbackError, res: any) => void): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: DocumentDefinition<DocType>, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
+    replaceOne(filter?: FilterQuery<DocType>, replacement?: Object, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<any, DocType, THelpers, RawDocType>;
 
     /** Specifies which document fields to include or exclude (also known as the query "projection") */
     select(arg: string | any): this;
@@ -2447,7 +2447,7 @@ declare module 'mongoose' {
     toConstructor(): new (...args: any[]) => QueryWithHelpers<ResultType, DocType, THelpers, RawDocType>;
 
     /** Declare and/or execute this query as an update() operation. */
-    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
+    update(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback<UpdateWriteOpResult>): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as an updateMany() operation. Same as
@@ -2455,13 +2455,13 @@ declare module 'mongoose' {
      * `filter` (as opposed to just the first one) regardless of the value of
      * the `multi` option.
      */
-    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
+    updateMany(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback<UpdateWriteOpResult>): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
 
     /**
      * Declare and/or execute this query as an updateOne() operation. Same as
      * `update()`, except it does not support the `multi` or `overwrite` options.
      */
-    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: (err: CallbackError, res: UpdateWriteOpResult) => void): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
+    updateOne(filter?: FilterQuery<DocType>, update?: UpdateQuery<DocType> | UpdateWithAggregationPipeline, options?: QueryOptions | null, callback?: Callback<UpdateWriteOpResult>): QueryWithHelpers<UpdateWriteOpResult, DocType, THelpers, RawDocType>;
 
     /**
      * Sets the specified number of `mongod` servers, or tag set of `mongod` servers,
@@ -2606,7 +2606,7 @@ declare module 'mongoose' {
      * `next()` will error.
      */
     close(): Promise<void>;
-    close(callback: (err: CallbackError) => void): void;
+    close(callback: Callback): void;
 
     /**
      * Execute `fn` for every document(s) in the cursor. If batchSize is provided
@@ -2616,8 +2616,8 @@ declare module 'mongoose' {
      */
     eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }): Promise<void>;
     eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }): Promise<void>;
-    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number, batchSize?: number }, cb?: (err: CallbackError) => void): void;
-    eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }, cb?: (err: CallbackError) => void): void;
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number, batchSize?: number }, cb?: Callback): void;
+    eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }, cb?: Callback): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
@@ -2630,7 +2630,7 @@ declare module 'mongoose' {
      * no documents left.
      */
     next(): Promise<DocType>;
-    next(callback: (err: CallbackError, doc: DocType | null) => void): void;
+    next(callback: Callback<DocType | null>): void;
 
     options: any;
   }
@@ -2672,10 +2672,10 @@ declare module 'mongoose' {
     cursor(options?: Record<string, unknown>): this;
 
     /** Executes the aggregate pipeline on the currently bound Model. If cursor option is set, returns a cursor */
-    exec(callback?: (err: CallbackError, result: R) => void): Promise<R> | any;
+    exec(callback?: Callback<R>): Promise<R> | any;
 
     /** Execute the aggregation with explain */
-    explain(callback?: (err: CallbackError, result: any) => void): Promise<any>;
+    explain(callback?: Callback): Promise<any>;
 
     /** Combines multiple aggregation pipelines. */
     facet(options: any): this;
@@ -2783,7 +2783,7 @@ declare module 'mongoose' {
      * `next()` will error.
      */
     close(): Promise<void>;
-    close(callback: (err: CallbackError) => void): void;
+    close(callback: Callback): void;
 
     /**
      * Execute `fn` for every document(s) in the cursor. If batchSize is provided
@@ -2792,7 +2792,7 @@ declare module 'mongoose' {
      * Returns a promise that resolves when done.
      */
     eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }): Promise<void>;
-    eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }, cb?: (err: CallbackError) => void): void;
+    eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }, cb?: Callback): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
@@ -2805,7 +2805,7 @@ declare module 'mongoose' {
      * no documents left.
      */
     next(): Promise<any>;
-    next(callback: (err: CallbackError, doc: any) => void): void;
+    next(callback: Callback): void;
   }
 
   class SchemaType {
@@ -2879,6 +2879,8 @@ declare module 'mongoose' {
       type?: string): this;
   }
 
+  type Callback<T = any> = (error: CallbackError, result: T) => void;
+
   class NativeError extends global.Error { }
   type CallbackError = NativeError | null;
 

From 0f49d67cadd09d7eb9afb0f16b8a650200b03b0e Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Sun, 8 Aug 2021 00:21:09 -0300
Subject: [PATCH 2263/2348] fix(index.d.ts): improve types of `Schema#(g|s)et`

---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index db22e85d056..beeb57b6aee 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1267,7 +1267,7 @@ declare module 'mongoose' {
     indexes(): Array<any>;
 
     /** Gets a schema option. */
-    get(path: string): any;
+    get<K extends keyof SchemaOptions>(key: K): SchemaOptions[K];
 
     /**
      * Loads an ES6 class into a schema. Maps [setters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set) + [getters](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/get), [static methods](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static),
@@ -1346,7 +1346,7 @@ declare module 'mongoose' {
     requiredPaths(invalidate?: boolean): string[];
 
     /** Sets a schema option. */
-    set(path: string, value: any, _tags?: any): this;
+    set<K extends keyof SchemaOptions>(key: K, value: SchemaOptions[K], _tags?: any): this;
 
     /** Adds static "class" methods to Models compiled from this schema. */
     static(name: string, fn: (this: M, ...args: any[]) => any): this;

From b96ad0013f7e9d91187412cbe8dc0f11bb40ac0f Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Sun, 8 Aug 2021 10:32:11 -0300
Subject: [PATCH 2264/2348] chore: add `types` property to `package.json`

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 52c977cde8d..0f575cddc7d 100644
--- a/package.json
+++ b/package.json
@@ -84,6 +84,7 @@
     "test-cov": "nyc --reporter=html --reporter=text npm test"
   },
   "main": "./index.js",
+  "types": "./index.d.ts",
   "engines": {
     "node": ">=4.0.0"
   },

From f746434a25fe6061571b16c0cfbbc5b28fe62671 Mon Sep 17 00:00:00 2001
From: Shahriar Shojib <shahriar_shojib@hotmail.com>
Date: Mon, 9 Aug 2021 08:23:43 +0600
Subject: [PATCH 2265/2348] relax types for non AtomicPush

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index c8bafd5382a..43deb904209 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1971,7 +1971,7 @@ declare module 'mongoose' {
       isMongooseArray: true;
 
       /** Pushes items to the array non-atomically. */
-      nonAtomicPush(...args: T[]): number;
+      nonAtomicPush(...args: Array<AnyKeys<T> & AnyObject>): number;
 
       /** Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking. */
       push(...args: T[]): number;

From 1c66cc972c90529bd0ffe8496e9de866b92a97fa Mon Sep 17 00:00:00 2001
From: Efe <48628713+Raader@users.noreply.github.com>
Date: Mon, 9 Aug 2021 12:51:00 +0300
Subject: [PATCH 2266/2348] use mongodb's index specification

---
 index.d.ts | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index f5c3df5dff0..e95be5ed45d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1231,8 +1231,6 @@ declare module 'mongoose' {
   type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
   type ErrorHandlingMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, err: NativeError, res: ResType, next: (err?: CallbackError) => void) => void;
-  
-  type Index = { [key: string]: boolean | number | string | Index }
 
   class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined, TInstanceMethods = ExtractMethods<M>> extends events.EventEmitter {
     /**
@@ -1261,13 +1259,13 @@ declare module 'mongoose' {
 
     
     /** Defines an index (most likely compound) for this schema. */
-    index(fields: Index, options?: IndexOptions): this;
+    index(fields: mongodb.IndexSpecification, options?: IndexOptions): this;
 
     /**
      * Returns a list of indexes that this schema declares, via `schema.index()`
      * or by `index: true` in a path's options.
      */
-    indexes(): Array<Index>;
+    indexes(): Array<any>;
 
     /** Gets a schema option. */
     get(path: string): any;

From 523becd676352f8ed5921b59a4d97361a6dda1a8 Mon Sep 17 00:00:00 2001
From: Efe <48628713+Raader@users.noreply.github.com>
Date: Mon, 9 Aug 2021 13:01:42 +0300
Subject: [PATCH 2267/2348] remove unnecessary space

---
 index.d.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index e95be5ed45d..51267148fef 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1257,7 +1257,6 @@ declare module 'mongoose' {
     /** Iterates the schemas paths similar to Array#forEach. */
     eachPath(fn: (path: string, type: SchemaType) => void): this;
 
-    
     /** Defines an index (most likely compound) for this schema. */
     index(fields: mongodb.IndexSpecification, options?: IndexOptions): this;
 

From 6f7471732600189f7d40f8559d4b0f90de46acfc Mon Sep 17 00:00:00 2001
From: Thiago Kisaki <66492727+thiagokisaki@users.noreply.github.com>
Date: Mon, 9 Aug 2021 08:46:36 -0300
Subject: [PATCH 2268/2348] add `CallbackWithoutResult` type

---
 index.d.ts | 66 ++++++++++++++++++++++++++++--------------------------
 1 file changed, 34 insertions(+), 32 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index ee88924b407..da93871e097 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -64,8 +64,8 @@ declare module 'mongoose' {
   export const STATES: typeof ConnectionStates;
 
   /** Opens Mongoose's default connection to MongoDB, see [connections docs](https://mongoosejs.com/docs/connections.html) */
-  export function connect(uri: string, options: ConnectOptions, callback: Callback): void;
-  export function connect(uri: string, callback: Callback): void;
+  export function connect(uri: string, options: ConnectOptions, callback: CallbackWithoutResult): void;
+  export function connect(uri: string, callback: CallbackWithoutResult): void;
   export function connect(uri: string, options?: ConnectOptions): Promise<Mongoose>;
 
   /** The Mongoose module's default connection. Equivalent to `mongoose.connections[0]`, see [`connections`](#mongoose_Mongoose-connections). */
@@ -89,7 +89,7 @@ declare module 'mongoose' {
   export function deleteModel(name: string | RegExp): typeof mongoose;
 
   export function disconnect(): Promise<void>;
-  export function disconnect(cb: Callback): void;
+  export function disconnect(cb: CallbackWithoutResult): void;
 
   /** Gets mongoose options */
   export function get<K extends keyof MongooseOptions>(key: K): MongooseOptions[K];
@@ -298,8 +298,8 @@ declare module 'mongoose' {
 
   class Connection extends events.EventEmitter {
     /** Closes the connection */
-    close(callback: Callback): void;
-    close(force: boolean, callback: Callback): void;
+    close(callback: CallbackWithoutResult): void;
+    close(force: boolean, callback: CallbackWithoutResult): void;
     close(force?: boolean): Promise<void>;
 
     /** Retrieves a collection, creating it if not cached. */
@@ -335,14 +335,14 @@ declare module 'mongoose' {
      * all documents and indexes.
      */
     dropCollection(collection: string): Promise<void>;
-    dropCollection(collection: string, cb: Callback): void;
+    dropCollection(collection: string, cb: CallbackWithoutResult): void;
 
     /**
      * Helper for `dropDatabase()`. Deletes the given database, including all
      * collections, documents, and indexes.
      */
     dropDatabase(): Promise<void>;
-    dropDatabase(cb: Callback): void;
+    dropDatabase(cb: CallbackWithoutResult): void;
 
     /** Gets the value of the option `key`. Equivalent to `conn.options[key]` */
     get(key: string): any;
@@ -389,8 +389,8 @@ declare module 'mongoose' {
 
     /** Opens the connection with a URI using `MongoClient.connect()`. */
     openUri(uri: string, options?: ConnectOptions): Promise<Connection>;
-    openUri(uri: string, callback: Callback<Connection>): Connection;
-    openUri(uri: string, options: ConnectOptions, callback: Callback<Connection>): Connection;
+    openUri(uri: string, callback: (err: CallbackError, conn?: Connection) => void): Connection;
+    openUri(uri: string, options: ConnectOptions, callback: (err: CallbackError, conn?: Connection) => void): Connection;
 
     /** The password specified in the URI */
     pass: string;
@@ -730,9 +730,9 @@ declare module 'mongoose' {
     /** Executes registered validation rules for this document. */
     validate(options:{ pathsToSkip?: pathsToSkip }): Promise<void>;
     validate(pathsToValidate?: pathsToValidate, options?: any): Promise<void>;
-    validate(callback: Callback): void;
-    validate(pathsToValidate: pathsToValidate, callback: Callback): void;
-    validate(pathsToValidate: pathsToValidate, options: any, callback: Callback): void;
+    validate(callback: CallbackWithoutResult): void;
+    validate(pathsToValidate: pathsToValidate, callback: CallbackWithoutResult): void;
+    validate(pathsToValidate: pathsToValidate, options: any, callback: CallbackWithoutResult): void;
 
     /** Executes registered validation rules (skipping asynchronous validators) for this document. */
     validateSync(options:{pathsToSkip?: pathsToSkip, [k:string]: any }): Error.ValidationError | null;
@@ -814,8 +814,8 @@ declare module 'mongoose' {
      * Similar to `ensureIndexes()`, except for it uses the [`createIndex`](http://mongodb.github.io/node-mongodb-native/2.2/api/Collection.html#createIndex)
      * function.
      */
-    createIndexes(callback?: Callback): Promise<void>;
-    createIndexes(options?: any, callback?: Callback): Promise<void>;
+    createIndexes(callback?: CallbackWithoutResult): Promise<void>;
+    createIndexes(options?: any, callback?: CallbackWithoutResult): Promise<void>;
 
     /** Connection the model uses. */
     db: Connection;
@@ -825,25 +825,25 @@ declare module 'mongoose' {
      * Behaves like `remove()`, but deletes all documents that match `conditions`
      * regardless of the `single` option.
      */
-    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteMany(filter: FilterQuery<T>, callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteMany(callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(filter?: FilterQuery<T>, options?: QueryOptions, callback?: CallbackWithoutResult): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(filter: FilterQuery<T>, callback: CallbackWithoutResult): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteMany(callback: CallbackWithoutResult): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Deletes the first document that matches `conditions` from the collection.
      * Behaves like `remove()`, but deletes at most one document regardless of the
      * `single` option.
      */
-    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteOne(filter: FilterQuery<T>, callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    deleteOne(callback: Callback): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(filter?: FilterQuery<T>, options?: QueryOptions, callback?: CallbackWithoutResult): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(filter: FilterQuery<T>, callback: CallbackWithoutResult): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    deleteOne(callback: CallbackWithoutResult): QueryWithHelpers<mongodb.DeleteWriteOpResultObject['result'] & { deletedCount?: number }, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /**
      * Sends `createIndex` commands to mongo for each index declared in the schema.
      * The `createIndex` commands are sent in series.
      */
-    ensureIndexes(callback?: Callback): Promise<void>;
-    ensureIndexes(options?: any, callback?: Callback): Promise<void>;
+    ensureIndexes(callback?: CallbackWithoutResult): Promise<void>;
+    ensureIndexes(options?: any, callback?: CallbackWithoutResult): Promise<void>;
 
     /**
      * Event emitter that reports any errors that occurred. Useful for global error
@@ -875,7 +875,7 @@ declare module 'mongoose' {
      * [`connection.model()`](/docs/api.html#connection_Connection-model), so you
      * don't need to call it.
      */
-    init(callback?: Callback): Promise<EnforceDocument<T, TMethods>>;
+    init(callback?: CallbackWithoutResult): Promise<EnforceDocument<T, TMethods>>;
 
     /** Inserts one or more new documents as a single `insertMany` call to the MongoDB server. */
     insertMany(docs: Array<T | DocumentDefinition<T> | AnyObject>, options: InsertManyOptions & { rawResult: true }): Promise<InsertManyResult>;
@@ -920,9 +920,9 @@ declare module 'mongoose' {
     startSession(options?: mongodb.SessionOptions, cb?: Callback<mongodb.ClientSession>): Promise<mongodb.ClientSession>;
 
     /** Casts and validates the given object against this model's schema, passing the given `context` to custom validators. */
-    validate(callback?: Callback): Promise<void>;
-    validate(optional: any, callback?: Callback): Promise<void>;
-    validate(optional: any, pathsToValidate: string[], callback?: Callback): Promise<void>;
+    validate(callback?: CallbackWithoutResult): Promise<void>;
+    validate(optional: any, callback?: CallbackWithoutResult): Promise<void>;
+    validate(optional: any, pathsToValidate: string[], callback?: CallbackWithoutResult): Promise<void>;
 
     /** Watches the underlying collection for changes using [MongoDB change streams](https://docs.mongodb.com/manual/changeStreams/). */
     watch(pipeline?: Array<Record<string, unknown>>, options?: mongodb.ChangeStreamOptions): mongodb.ChangeStream;
@@ -989,7 +989,7 @@ declare module 'mongoose' {
       callback?: Callback
     ): Promise<any>;
 
-    remove(filter?: any, callback?: Callback): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    remove(filter?: any, callback?: CallbackWithoutResult): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `replaceOne` query: finds the first document that matches `filter` and replaces it with `replacement`. */
     replaceOne(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: Callback): QueryWithHelpers<any, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
@@ -2606,7 +2606,7 @@ declare module 'mongoose' {
      * `next()` will error.
      */
     close(): Promise<void>;
-    close(callback: Callback): void;
+    close(callback: CallbackWithoutResult): void;
 
     /**
      * Execute `fn` for every document(s) in the cursor. If batchSize is provided
@@ -2616,8 +2616,8 @@ declare module 'mongoose' {
      */
     eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number }): Promise<void>;
     eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }): Promise<void>;
-    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number, batchSize?: number }, cb?: Callback): void;
-    eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }, cb?: Callback): void;
+    eachAsync(fn: (doc: DocType) => any, options?: { parallel?: number, batchSize?: number }, cb?: CallbackWithoutResult): void;
+    eachAsync(fn: (doc: DocType[]) => any, options: { parallel?: number, batchSize: number }, cb?: CallbackWithoutResult): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
@@ -2783,7 +2783,7 @@ declare module 'mongoose' {
      * `next()` will error.
      */
     close(): Promise<void>;
-    close(callback: Callback): void;
+    close(callback: CallbackWithoutResult): void;
 
     /**
      * Execute `fn` for every document(s) in the cursor. If batchSize is provided
@@ -2792,7 +2792,7 @@ declare module 'mongoose' {
      * Returns a promise that resolves when done.
      */
     eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }): Promise<void>;
-    eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }, cb?: Callback): void;
+    eachAsync(fn: (doc: any) => any, options?: { parallel?: number, batchSize?: number }, cb?: CallbackWithoutResult): void;
 
     /**
      * Registers a transform function which subsequently maps documents retrieved
@@ -2881,6 +2881,8 @@ declare module 'mongoose' {
 
   type Callback<T = any> = (error: CallbackError, result: T) => void;
 
+  type CallbackWithoutResult = (error: CallbackError) => void;
+
   class NativeError extends global.Error { }
   type CallbackError = NativeError | null;
 

From a0bdcfe5ea357e2cd2ae15e16c877bf0e914442b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 11:01:04 -0400
Subject: [PATCH 2269/2348] fix(cursor): make sure to clear stack every 1000
 docs when calling `next()` to avoid stack overflow with large batch size

Fix #10449
---
 lib/cursor/QueryCursor.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index f38229bd848..49e3a4d9d10 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -422,6 +422,11 @@ function _onNext(error, doc) {
   this.ctx._batchDocs.push(doc);
 
   if (this.ctx._batchDocs.length < this.ctx.options._populateBatchSize) {
+    // If both `batchSize` and `_populateBatchSize` are huge, calling `next()` repeatedly may
+    // cause a stack overflow. So make sure we clear the stack regularly.
+    if (this.ctx._batchDocs.length > 0 && this.ctx._batchDocs.length % 1000 === 0) {
+      return immediate(() => this.ctx.cursor.next(_onNext.bind(this)));
+    }
     this.ctx.cursor.next(_onNext.bind(this));
   } else {
     _populateBatch.call(this);

From bf54ac2d76183419be09f409c553b8aa02a5c1bf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 11:30:47 -0400
Subject: [PATCH 2270/2348] test(update): repro #10512

---
 lib/helpers/getConstructorName.js | 15 +++++++++++++++
 test/model.test.js                | 15 +++++++++++++++
 2 files changed, 30 insertions(+)
 create mode 100644 lib/helpers/getConstructorName.js

diff --git a/lib/helpers/getConstructorName.js b/lib/helpers/getConstructorName.js
new file mode 100644
index 00000000000..a4e19249318
--- /dev/null
+++ b/lib/helpers/getConstructorName.js
@@ -0,0 +1,15 @@
+'use strict';
+
+/*!
+ * If `val` is an object, returns constructor name, if possible. Otherwise returns undefined.
+ */
+
+module.exports = function getConstructorName(val) {
+  if (val == null) {
+    return void 0;
+  }
+  if (typeof val.constructor !== 'function') {
+    return void 0;
+  }
+  return val.constructor.name;
+};
\ No newline at end of file
diff --git a/test/model.test.js b/test/model.test.js
index 3130505b3ca..acf3f31ff9a 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5876,6 +5876,21 @@ describe('Model', function() {
           }
         });
       });
+
+      it('casts objects with null prototype (gh-10512)', function() {
+        const schema = Schema({
+          _id: String,
+          someArray: [{ message: String }]
+        });
+        const Test = db.model('Test', schema);
+    
+        return Test.bulkWrite([{
+          updateOne: {
+            filter: {},
+            update: { $set: { 'someArray.1': { __proto__: null, message: 'test' } } }
+          }
+        }])
+      });
     });
 
     it('insertMany with Decimal (gh-5190)', function(done) {

From a37f63ce89563f98104840e25b402d9bfb03d217 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 11:42:23 -0400
Subject: [PATCH 2271/2348] fix: add explicit check on `constructor` property
 to avoid throwing an error when checking objects with null prototypes

Fix #10512
---
 lib/aggregate.js                              |  3 ++-
 lib/cast.js                                   |  3 ++-
 lib/drivers/node-mongodb-native/collection.js | 21 +++++++++++--------
 lib/error/validation.js                       |  3 ++-
 .../populate/getModelsMapForPopulate.js       |  4 ++--
 lib/helpers/query/castUpdate.js               |  3 ++-
 lib/helpers/topology/allServersUnknown.js     |  5 +++--
 lib/helpers/topology/isAtlas.js               |  5 +++--
 lib/helpers/topology/isSSLError.js            |  5 +++--
 lib/model.js                                  |  4 ++--
 lib/query.js                                  |  6 +++---
 lib/schema.js                                 |  3 ++-
 lib/schema/date.js                            |  3 ++-
 lib/schema/objectid.js                        |  3 ++-
 lib/types/map.js                              |  3 ++-
 test/model.test.js                            |  4 ++--
 16 files changed, 46 insertions(+), 32 deletions(-)

diff --git a/lib/aggregate.js b/lib/aggregate.js
index 1f3251e6e29..451b820126e 100644
--- a/lib/aggregate.js
+++ b/lib/aggregate.js
@@ -7,6 +7,7 @@
 const AggregationCursor = require('./cursor/AggregationCursor');
 const Query = require('./query');
 const applyGlobalMaxTimeMS = require('./helpers/query/applyGlobalMaxTimeMS');
+const getConstructorName = require('./helpers/getConstructorName');
 const promiseOrCallback = require('./helpers/promiseOrCallback');
 const stringifyFunctionOperators = require('./helpers/aggregate/stringifyFunctionOperators');
 const util = require('util');
@@ -562,7 +563,7 @@ Aggregate.prototype.sort = function(arg) {
 
   const sort = {};
 
-  if (arg.constructor.name === 'Object') {
+  if (getConstructorName(arg) === 'Object') {
     const desc = ['desc', 'descending', -1];
     Object.keys(arg).forEach(function(field) {
       // If sorting by text score, skip coercing into 1/-1
diff --git a/lib/cast.js b/lib/cast.js
index 1c24bc7fe65..94543f4468c 100644
--- a/lib/cast.js
+++ b/lib/cast.js
@@ -9,6 +9,7 @@ const StrictModeError = require('./error/strict');
 const Types = require('./schema/index');
 const castTextSearch = require('./schema/operators/text');
 const get = require('./helpers/get');
+const getConstructorName = require('./helpers/getConstructorName');
 const getSchemaDiscriminatorByValue = require('./helpers/discriminator/getSchemaDiscriminatorByValue');
 const isOperator = require('./helpers/query/isOperator');
 const util = require('util');
@@ -267,7 +268,7 @@ module.exports = function cast(schema, obj, options, context) {
         }
       } else if (val == null) {
         continue;
-      } else if (val.constructor.name === 'Object') {
+      } else if (getConstructorName(val) === 'Object') {
         any$conditionals = Object.keys(val).some(isOperator);
 
         if (!any$conditionals) {
diff --git a/lib/drivers/node-mongodb-native/collection.js b/lib/drivers/node-mongodb-native/collection.js
index 95f8652df1a..34241f2d2eb 100644
--- a/lib/drivers/node-mongodb-native/collection.js
+++ b/lib/drivers/node-mongodb-native/collection.js
@@ -9,6 +9,7 @@ const MongooseError = require('../../error/mongooseError');
 const Collection = require('mongodb').Collection;
 const ObjectId = require('./objectid');
 const get = require('../../helpers/get');
+const getConstructorName = require('../../helpers/getConstructorName');
 const sliced = require('sliced');
 const stream = require('stream');
 const util = require('util');
@@ -376,14 +377,15 @@ function format(obj, sub, color, shell) {
 
   const clone = require('../../helpers/clone');
   let x = clone(obj, { transform: false });
+  const constructorName = getConstructorName(x);
 
-  if (x.constructor.name === 'Binary') {
+  if (constructorName === 'Binary') {
     x = 'BinData(' + x.sub_type + ', "' + x.toString('base64') + '")';
-  } else if (x.constructor.name === 'ObjectID') {
+  } else if (constructorName === 'ObjectID') {
     x = inspectable('ObjectId("' + x.toHexString() + '")');
-  } else if (x.constructor.name === 'Date') {
+  } else if (constructorName === 'Date') {
     x = inspectable('new Date("' + x.toUTCString() + '")');
-  } else if (x.constructor.name === 'Object') {
+  } else if (constructorName === 'Object') {
     const keys = Object.keys(x);
     const numKeys = keys.length;
     let key;
@@ -402,16 +404,17 @@ function format(obj, sub, color, shell) {
             error = _error;
           }
         }
-        if (x[key].constructor.name === 'Binary') {
+        const _constructorName = getConstructorName(x[key]);
+        if (_constructorName === 'Binary') {
           x[key] = 'BinData(' + x[key].sub_type + ', "' +
             x[key].buffer.toString('base64') + '")';
-        } else if (x[key].constructor.name === 'Object') {
+        } else if (_constructorName === 'Object') {
           x[key] = format(x[key], true);
-        } else if (x[key].constructor.name === 'ObjectID') {
+        } else if (_constructorName === 'ObjectID') {
           formatObjectId(x, key);
-        } else if (x[key].constructor.name === 'Date') {
+        } else if (_constructorName === 'Date') {
           formatDate(x, key, shell);
-        } else if (x[key].constructor.name === 'ClientSession') {
+        } else if (_constructorName === 'ClientSession') {
           x[key] = inspectable('ClientSession("' +
             get(x[key], 'id.id.buffer', '').toString('hex') + '")');
         } else if (Array.isArray(x[key])) {
diff --git a/lib/error/validation.js b/lib/error/validation.js
index 7b4047620d1..783554aaa1c 100644
--- a/lib/error/validation.js
+++ b/lib/error/validation.js
@@ -5,6 +5,7 @@
 'use strict';
 
 const MongooseError = require('./mongooseError');
+const getConstructorName = require('../helpers/getConstructorName');
 const util = require('util');
 
 class ValidationError extends MongooseError {
@@ -17,7 +18,7 @@ class ValidationError extends MongooseError {
    */
   constructor(instance) {
     let _message;
-    if (instance && instance.constructor.name === 'model') {
+    if (getConstructorName(instance) === 'model') {
       _message = instance.constructor.modelName + ' validation failed';
     } else {
       _message = 'Validation failed';
diff --git a/lib/helpers/populate/getModelsMapForPopulate.js b/lib/helpers/populate/getModelsMapForPopulate.js
index f98731bca53..5cc6c3f6f88 100644
--- a/lib/helpers/populate/getModelsMapForPopulate.js
+++ b/lib/helpers/populate/getModelsMapForPopulate.js
@@ -5,6 +5,7 @@ const SkipPopulateValue = require('./SkipPopulateValue');
 const get = require('../get');
 const getDiscriminatorByValue = require('../discriminator/getDiscriminatorByValue');
 const isPathExcluded = require('../projection/isPathExcluded');
+const getConstructorName = require('../getConstructorName');
 const getSchemaTypes = require('./getSchemaTypes');
 const getVirtual = require('./getVirtual');
 const lookupLocalFields = require('./lookupLocalFields');
@@ -520,8 +521,7 @@ function convertTo_id(val, schema) {
 
   // `populate('map')` may be an object if populating on a doc that hasn't
   // been hydrated yet
-  if (val != null &&
-      val.constructor.name === 'Object' &&
+  if (getConstructorName(val) === 'Object' &&
       // The intent here is we should only flatten the object if we expect
       // to get a Map in the end. Avoid doing this for mixed types.
       (schema == null || schema[schemaMixedSymbol] == null)) {
diff --git a/lib/helpers/query/castUpdate.js b/lib/helpers/query/castUpdate.js
index b14efc30d49..ca9ad4f04a5 100644
--- a/lib/helpers/query/castUpdate.js
+++ b/lib/helpers/query/castUpdate.js
@@ -6,6 +6,7 @@ const StrictModeError = require('../../error/strict');
 const ValidationError = require('../../error/validation');
 const castNumber = require('../../cast/number');
 const cast = require('../../cast');
+const getConstructorName = require('../getConstructorName');
 const getEmbeddedDiscriminatorPath = require('./getEmbeddedDiscriminatorPath');
 const handleImmutable = require('./handleImmutable');
 const moveImmutableProperties = require('../update/moveImmutableProperties');
@@ -200,7 +201,7 @@ function walkUpdatePath(schema, obj, op, options, context, filter, pref) {
       }
     }
 
-    if (val && val.constructor.name === 'Object') {
+    if (getConstructorName(val) === 'Object') {
       // watch for embedded doc schemas
       schematype = schema._getSchema(prefix + key);
 
diff --git a/lib/helpers/topology/allServersUnknown.js b/lib/helpers/topology/allServersUnknown.js
index d3c7b4b07b4..33d23ab3e7e 100644
--- a/lib/helpers/topology/allServersUnknown.js
+++ b/lib/helpers/topology/allServersUnknown.js
@@ -1,8 +1,9 @@
 'use strict';
 
+const getConstructorName = require('../getConstructorName');
+
 module.exports = function allServersUnknown(topologyDescription) {
-  if (topologyDescription == null ||
-      topologyDescription.constructor.name !== 'TopologyDescription') {
+  if (getConstructorName(topologyDescription) !== 'TopologyDescription') {
     return false;
   }
 
diff --git a/lib/helpers/topology/isAtlas.js b/lib/helpers/topology/isAtlas.js
index 3bb8129e3b7..f0638d55136 100644
--- a/lib/helpers/topology/isAtlas.js
+++ b/lib/helpers/topology/isAtlas.js
@@ -1,8 +1,9 @@
 'use strict';
 
+const getConstructorName = require('../getConstructorName');
+
 module.exports = function isAtlas(topologyDescription) {
-  if (topologyDescription == null ||
-    topologyDescription.constructor.name !== 'TopologyDescription') {
+  if (getConstructorName(topologyDescription) !== 'TopologyDescription') {
     return false;
   }
 
diff --git a/lib/helpers/topology/isSSLError.js b/lib/helpers/topology/isSSLError.js
index 61e57d1d286..d910fc8344c 100644
--- a/lib/helpers/topology/isSSLError.js
+++ b/lib/helpers/topology/isSSLError.js
@@ -1,11 +1,12 @@
 'use strict';
 
+const getConstructorName = require('../getConstructorName');
+
 const nonSSLMessage = 'Client network socket disconnected before secure TLS ' +
   'connection was established';
 
 module.exports = function isSSLError(topologyDescription) {
-  if (topologyDescription == null ||
-    topologyDescription.constructor.name !== 'TopologyDescription') {
+  if (getConstructorName(topologyDescription) !== 'TopologyDescription') {
     return false;
   }
 
diff --git a/lib/model.js b/lib/model.js
index 46709d041af..766c84a7c82 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -35,6 +35,7 @@ const getDefaultBulkwriteResult = require('./helpers/getDefaultBulkwriteResult')
 const discriminator = require('./helpers/model/discriminator');
 const each = require('./helpers/each');
 const get = require('./helpers/get');
+const getConstructorName = require('./helpers/getConstructorName');
 const getDiscriminatorByValue = require('./helpers/discriminator/getDiscriminatorByValue');
 const getModelsMapForPopulate = require('./helpers/populate/getModelsMapForPopulate');
 const immediate = require('./helpers/immediate');
@@ -3113,8 +3114,7 @@ Model.create = function create(doc, options, callback) {
         args[0] != null &&
         args[1] != null &&
         args[0].session == null &&
-        last.session != null &&
-        last.session.constructor.name === 'ClientSession' &&
+        getConstructorName(last.session) === 'ClientSession' &&
         !this.schema.path('session')) {
       // Probably means the user is running into the common mistake of trying
       // to use a spread to specify options, see gh-7535
diff --git a/lib/query.js b/lib/query.js
index fee31ad7ffd..af16622fc84 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -5128,7 +5128,7 @@ Query.prototype.maxscan = Query.base.maxScan;
 Query.prototype.tailable = function(val, opts) {
   // we need to support the tailable({ awaitdata : true }) as well as the
   // tailable(true, {awaitdata :true}) syntax that mquery does not support
-  if (val && val.constructor.name === 'Object') {
+  if (val != null && typeof val.constructor === 'function' && val.constructor.name === 'Object') {
     opts = val;
     val = true;
   }
@@ -5485,11 +5485,11 @@ Query.prototype.center = Query.base.circle;
  */
 
 Query.prototype.centerSphere = function() {
-  if (arguments[0] && arguments[0].constructor.name === 'Object') {
+  if (arguments[0] != null && typeof arguments[0].constructor === 'function' && arguments[0].constructor.name === 'Object') {
     arguments[0].spherical = true;
   }
 
-  if (arguments[1] && arguments[1].constructor.name === 'Object') {
+  if (arguments[1] != null && typeof arguments[1].constructor === 'function' && arguments[1].constructor.name === 'Object') {
     arguments[1].spherical = true;
   }
 
diff --git a/lib/schema.js b/lib/schema.js
index e298742bec8..77d56e746c6 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -14,6 +14,7 @@ const VirtualType = require('./virtualtype');
 const addAutoId = require('./helpers/schema/addAutoId');
 const arrayParentSymbol = require('./helpers/symbols').arrayParentSymbol;
 const get = require('./helpers/get');
+const getConstructorName = require('./helpers/getConstructorName');
 const getIndexes = require('./helpers/schema/getIndexes');
 const merge = require('./helpers/schema/merge');
 const mpath = require('mpath');
@@ -1702,7 +1703,7 @@ Schema.prototype.indexes = function() {
  */
 
 Schema.prototype.virtual = function(name, options) {
-  if (name instanceof VirtualType || (name != null && name.constructor.name === 'VirtualType')) {
+  if (name instanceof VirtualType || getConstructorName(name) === 'VirtualType') {
     return this.virtual(name.path, name.options);
   }
 
diff --git a/lib/schema/date.js b/lib/schema/date.js
index fb7f061c1f6..5ee0eb9e98c 100644
--- a/lib/schema/date.js
+++ b/lib/schema/date.js
@@ -8,6 +8,7 @@ const MongooseError = require('../error/index');
 const SchemaDateOptions = require('../options/SchemaDateOptions');
 const SchemaType = require('../schematype');
 const castDate = require('../cast/date');
+const getConstructorName = require('../helpers/getConstructorName');
 const utils = require('../utils');
 
 const CastError = SchemaType.CastError;
@@ -147,7 +148,7 @@ SchemaDate._defaultCaster = v => {
  */
 
 SchemaDate.prototype.expires = function(when) {
-  if (!this._index || this._index.constructor.name !== 'Object') {
+  if (getConstructorName(this._index) !== 'Object') {
     this._index = {};
   }
 
diff --git a/lib/schema/objectid.js b/lib/schema/objectid.js
index 157ed7d9257..21105b66e9f 100644
--- a/lib/schema/objectid.js
+++ b/lib/schema/objectid.js
@@ -7,6 +7,7 @@
 const SchemaObjectIdOptions = require('../options/SchemaObjectIdOptions');
 const SchemaType = require('../schematype');
 const castObjectId = require('../cast/objectid');
+const getConstructorName = require('../helpers/getConstructorName');
 const oid = require('../types/objectid');
 const utils = require('../utils');
 
@@ -225,7 +226,7 @@ ObjectId.prototype.cast = function(value, doc, init) {
     // wait! we may need to cast this to a document
     if (value instanceof oid) {
       return value;
-    } else if (value != null && (value.constructor.name || '').toLowerCase() === 'objectid') {
+    } else if ((getConstructorName(value) || '').toLowerCase() === 'objectid') {
       return new oid(value.toHexString());
     }
 
diff --git a/lib/types/map.js b/lib/types/map.js
index 1cfcd06fef3..fc2b7056bdd 100644
--- a/lib/types/map.js
+++ b/lib/types/map.js
@@ -5,6 +5,7 @@ const ObjectId = require('./objectid');
 const clone = require('../helpers/clone');
 const deepEqual = require('../utils').deepEqual;
 const get = require('../helpers/get');
+const getConstructorName = require('../helpers/getConstructorName');
 const handleSpreadDoc = require('../helpers/document/handleSpreadDoc');
 const util = require('util');
 const specialProperties = require('../helpers/specialProperties');
@@ -17,7 +18,7 @@ const populateModelSymbol = require('../helpers/symbols').populateModelSymbol;
 
 class MongooseMap extends Map {
   constructor(v, path, doc, schemaType) {
-    if (v != null && v.constructor.name === 'Object') {
+    if (getConstructorName(v) === 'Object') {
       v = Object.keys(v).reduce((arr, key) => arr.concat([[key, v[key]]]), []);
     }
     super(v);
diff --git a/test/model.test.js b/test/model.test.js
index acf3f31ff9a..78359cc455f 100644
--- a/test/model.test.js
+++ b/test/model.test.js
@@ -5883,13 +5883,13 @@ describe('Model', function() {
           someArray: [{ message: String }]
         });
         const Test = db.model('Test', schema);
-    
+
         return Test.bulkWrite([{
           updateOne: {
             filter: {},
             update: { $set: { 'someArray.1': { __proto__: null, message: 'test' } } }
           }
-        }])
+        }]);
       });
     });
 

From 99ae1997a5467b8aeb3d34eb0674aa7a0640e88e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 11:46:08 -0400
Subject: [PATCH 2272/2348] fix(index.d.ts): add useNewUrlParser and
 useUnifiedTopology to ConnectOptions

Fix #10500
---
 index.d.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index e0aa9d00aee..69541eb17e0 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -294,6 +294,10 @@ declare module 'mongoose' {
     autoCreate?: boolean;
     /** False by default. If `true`, this connection will use `createIndex()` instead of `ensureIndex()` for automatic index builds via `Model.init()`. */
     useCreateIndex?: boolean;
+    /** false by default. Set to `true` to make all connections set the `useNewUrlParser` option by default */
+    useNewUrlParser?: boolean;
+    /** false by default. Set to `true` to make all connections set the `useUnifiedTopology` option by default */
+    useUnifiedTopology?: boolean;
   }
 
   class Connection extends events.EventEmitter {

From cdd4116946d0a9226f1d1c759db50d873fb5d67c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 12:30:37 -0400
Subject: [PATCH 2273/2348] docs(schema): add more info and examples to
 `Schema#indexes()` docs

Fix #10446
---
 lib/schema.js | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/schema.js b/lib/schema.js
index 77d56e746c6..68f1943f386 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1666,8 +1666,8 @@ Object.defineProperty(Schema, 'indexTypes', {
 });
 
 /**
- * Returns a list of indexes that this schema declares, via `schema.index()`
- * or by `index: true` in a path's options.
+ * Returns a list of indexes that this schema declares, via `schema.index()` or by `index: true` in a path's options.
+ * Indexes are expressed as an array `[spec, options]`.
  *
  * ####Example:
  *
@@ -1680,6 +1680,17 @@ Object.defineProperty(Schema, 'indexTypes', {
  *     //   [ { registeredAt: 1 }, { background: true } ] ]
  *     userSchema.indexes();
  *
+ * [Plugins](/docs/plugins.html) can use the return value of this function to modify a schema's indexes.
+ * For example, the below plugin makes every index unique by default.
+ *
+ *     function myPlugin(schema) {
+ *       for (const index of schema.indexes()) {
+ *         if (index[1].unique === undefined) {
+ *           index[1].unique = true;
+ *         }
+ *       }
+ *     }
+ *
  * @api public
  * @return {Array} list of indexes defined in the schema
  */

From ee5b391f1a5669fe26d9d2d17838d1aac7850a01 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 12:58:34 -0400
Subject: [PATCH 2274/2348] fix(schema): throw more helpful error when defining
 a document array using a schema from a different copy of the Mongoose module

Fix #10453
---
 lib/schema.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index 68f1943f386..9130e219b5d 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -933,11 +933,21 @@ Schema.prototype.interpretAsType = function(path, obj, options) {
       : type[0];
 
     if (cast && cast.instanceOfSchema) {
+      if (!(cast instanceof Schema)) {
+        throw new TypeError('Schema for array path `' + path +
+          '` is from a different copy of the Mongoose module. Please make sure you\'re using the same version ' +
+          'of Mongoose everywhere with `npm list mongoose`.');
+      }
       return new MongooseTypes.DocumentArray(path, cast, obj);
     }
     if (cast &&
         cast[options.typeKey] &&
         cast[options.typeKey].instanceOfSchema) {
+      if (!(cast[options.typeKey] instanceof Schema)) {
+        throw new TypeError('Schema for array path `' + path +
+          '` is from a different copy of the Mongoose module. Please make sure you\'re using the same version ' +
+          'of Mongoose everywhere with `npm list mongoose`.');
+      }
       return new MongooseTypes.DocumentArray(path, cast[options.typeKey], obj, cast);
     }
 

From 2cffb31997be00e528af1ac6689c299ccd639d4b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 13:22:48 -0400
Subject: [PATCH 2275/2348] fix(index.d.ts): allow calling `new Model(...)`
 with generic Model param

Fix #10526
---
 index.d.ts                  | 2 +-
 test/typescript/document.ts | 8 ++++++--
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4a3c28efd1a..c6470be95bc 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -754,7 +754,7 @@ declare module 'mongoose' {
     discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
   }
 
-  type AnyKeys<T> = Partial<{ [P in keyof T]: T[P] | any }>;
+  type AnyKeys<T> = { [P in keyof T]?: T[P] | any };
   interface AnyObject { [k: string]: any }
   type EnforceDocument<T, TMethods> = T extends Document ? T : T & Document<any, any, T> & TMethods;
 
diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index c1aae6c900c..320ceb6446b 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document, Error } from 'mongoose';
+import { Schema, model, Model, Document, Error } from 'mongoose';
 
 const schema: Schema = new Schema({ name: { type: 'String', required: true }, address: new Schema({ city: { type: String, required: true } }) });
 
@@ -32,4 +32,8 @@ void async function run() {
   test.validate({ pathsToSkip: 'name age' });
   test.validateSync({ pathsToSkip: ['name', 'age'] });
   test.validateSync({ pathsToSkip: 'name age' });
-})();
\ No newline at end of file
+})();
+
+function gh10526<U extends ITest>(arg1: Model<U>) {
+  const t = new arg1({ name: 'hello' });
+};
\ No newline at end of file

From 63a8b30dae522cc21fa3b3af4514daa900e13adb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 15:07:50 -0400
Subject: [PATCH 2276/2348] style: fix lint

---
 test/typescript/document.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index 320ceb6446b..8abde523a7d 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -36,4 +36,4 @@ void async function run() {
 
 function gh10526<U extends ITest>(arg1: Model<U>) {
   const t = new arg1({ name: 'hello' });
-};
\ No newline at end of file
+}
\ No newline at end of file

From 477afdc8aa1297b87e784085133617765a059a4d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 9 Aug 2021 15:29:20 -0400
Subject: [PATCH 2277/2348] chore: release 5.13.6

---
 History.md   | 14 ++++++++++++++
 package.json |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index f0bb4529a18..66d22d57032 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,17 @@
+5.13.6 / 2021-08-09
+===================
+ * fix: upgrade mongodb driver -> 3.6.11 #10543 [maon-fp](https://github.com/maon-fp)
+ * fix(schema): throw more helpful error when defining a document array using a schema from a different copy of the Mongoose module #10453
+ * fix: add explicit check on constructor property to avoid throwing an error when checking objects with null prototypes #10512
+ * fix(cursor): make sure to clear stack every 1000 docs when calling `next()` to avoid stack overflow with large batch size #10449
+ * fix(index.d.ts): allow calling new Model(...) with generic Model param #10526
+ * fix(index.d.ts): update type declarations of Schema.index method #10538 #10530 [Raader](https://github.com/Raader)
+ * fix(index.d.ts): add useNewUrlParser and useUnifiedTopology to ConnectOptions #10500
+ * fix(index.d.ts): add missing type for diffIndexes #10547 [bvgusak](https://github.com/bvgusak)
+ * fix(index.d.ts): fixed incorrect type definition for Query's .map function #10544 [GCastilho](https://github.com/GCastilho)
+ * docs(schema): add more info and examples to Schema#indexes() docs #10446
+ * chore: add types property to package.json #10557 [thiagokisaki](https://github.com/thiagokisaki)
+
 5.13.5 / 2021-07-30
 ===================
  * perf(index.d.ts): improve typescript type checking performance #10515 [andreialecu](https://github.com/andreialecu)
diff --git a/package.json b/package.json
index 2a4c95bf790..95d51dc2ce8 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.5",
+  "version": "5.13.6",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From d70ea43992823737999071890dfd88deaf8950a9 Mon Sep 17 00:00:00 2001
From: Jared Reisinger <JaredReisinger@users.noreply.github.com>
Date: Mon, 9 Aug 2021 16:18:48 -0700
Subject: [PATCH 2278/2348] Fix type for schema.index() to reflect actual
 mongoose API

Commit 1c66cc972c90529bd0ffe8496e9de866b92a97fa broke the typing for `Schema.index()` by making `fields` look like mongo's `IndexSpecification`, when it's not: mongoose has its own idea about what the index specification looks like.

(I'm not 100% sure about the changed return value on `Schema.indexes()`... there may be prefixing and a `background` field added, as per https://github.com/Automattic/mongoose/blob/master/lib/helpers/schema/getIndexes.js.)

Fixes #10561.
---
 index.d.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c6470be95bc..df7969173d3 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1246,6 +1246,8 @@ declare module 'mongoose' {
   type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
+  type IndexDefinition<T> = { [K in keyof T]: 1 | -1; };
+
   type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
   type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
@@ -1277,13 +1279,13 @@ declare module 'mongoose' {
     eachPath(fn: (path: string, type: SchemaType) => void): this;
 
     /** Defines an index (most likely compound) for this schema. */
-    index(fields: mongodb.IndexSpecification, options?: IndexOptions): this;
+    index(fields: IndexDefinition<SchemaDefinition<DocumentDefinition<SchemaDefinitionType>>>, options?: IndexOptions): this;
 
     /**
      * Returns a list of indexes that this schema declares, via `schema.index()`
      * or by `index: true` in a path's options.
      */
-    indexes(): Array<any>;
+    indexes(): Array<IndexDefinition<SchemaDefinition<DocumentDefinition<SchemaDefinitionType>>>>;
 
     /** Gets a schema option. */
     get<K extends keyof SchemaOptions>(key: K): SchemaOptions[K];

From f6d1ae6585b5586d0a9f91eb0d6b3e6044adc2b3 Mon Sep 17 00:00:00 2001
From: Jared Reisinger <JaredReisinger@users.noreply.github.com>
Date: Mon, 9 Aug 2021 16:55:06 -0700
Subject: [PATCH 2279/2348] Define `IndexOptions` in terms of
 `mongodb.IndexOptions`

The current mongoose.IndexOptions is missing some mongo-valid paroperties, like `partialFilterExpression`.
---
 index.d.ts | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c6470be95bc..cc7b309558c 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1732,12 +1732,8 @@ declare module 'mongoose' {
     RawId extends RefType = (PopulatedType extends { _id?: RefType; } ? NonNullable<PopulatedType['_id']> : mongoose.Types.ObjectId) | undefined
     > = PopulatedType | RawId;
 
-  interface IndexOptions {
-    background?: boolean,
+  interface IndexOptions extends mongodb.IndexOptions {
     expires?: number | string
-    sparse?: boolean,
-    type?: string,
-    unique?: boolean
   }
 
   interface ValidatorProps {

From bdb68c3aa28478874d37415a984d0322aff36be7 Mon Sep 17 00:00:00 2001
From: Jared Reisinger <jaredreisinger@hotmail.com>
Date: Mon, 9 Aug 2021 17:24:10 -0700
Subject: [PATCH 2280/2348] add `IndexDirection` for index sorting direction

---
 index.d.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index df7969173d3..4b56f182250 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1246,7 +1246,8 @@ declare module 'mongoose' {
   type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
-  type IndexDefinition<T> = { [K in keyof T]: 1 | -1; };
+  type IndexDirection = 1 | -1;
+  type IndexDefinition<T> = { [K in keyof T]: IndexDirection; };
 
   type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
   type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;

From 53d2c125493e349dddbf3f31da25c66d3bc16be3 Mon Sep 17 00:00:00 2001
From: Jared Reisinger <jaredreisinger@hotmail.com>
Date: Tue, 10 Aug 2021 10:22:42 -0700
Subject: [PATCH 2281/2348] allow any string index property name

---
 index.d.ts | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 4b56f182250..5ce3bf9d365 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1246,9 +1246,9 @@ declare module 'mongoose' {
   type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
-  type IndexDirection = 1 | -1;
-  type IndexDefinition<T> = { [K in keyof T]: IndexDirection; };
-
+  type IndexDirection = 1 | -1 | '2d' | '2dsphere' | 'geoHaystack' | 'hashed' | 'text';
+  type IndexDefinition = Record<string, IndexDirection>;
+  
   type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
   type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
@@ -1280,13 +1280,13 @@ declare module 'mongoose' {
     eachPath(fn: (path: string, type: SchemaType) => void): this;
 
     /** Defines an index (most likely compound) for this schema. */
-    index(fields: IndexDefinition<SchemaDefinition<DocumentDefinition<SchemaDefinitionType>>>, options?: IndexOptions): this;
+    index(fields: IndexDefinition, options?: IndexOptions): this;
 
     /**
      * Returns a list of indexes that this schema declares, via `schema.index()`
      * or by `index: true` in a path's options.
      */
-    indexes(): Array<IndexDefinition<SchemaDefinition<DocumentDefinition<SchemaDefinitionType>>>>;
+    indexes(): Array<IndexDefinition>;
 
     /** Gets a schema option. */
     get<K extends keyof SchemaOptions>(key: K): SchemaOptions[K];

From a1dd24e6e2a629b23bf3dbc318c6f5b9155eb869 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Aug 2021 18:53:55 -0400
Subject: [PATCH 2282/2348] fix(index.d.ts): correct type for `expires`

Fix #10529
---
 index.d.ts    | 2 +-
 lib/schema.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c6470be95bc..d845edf528d 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1677,7 +1677,7 @@ declare module 'mongoose' {
     max?: number | NativeDate | [number, string] | [NativeDate, string] | readonly [number, string] | readonly [NativeDate, string];
 
     /** Defines a TTL index on this path. Only allowed for dates. */
-    expires?: number | NativeDate;
+    expires?: string | number;
 
     /** If `true`, Mongoose will skip gathering indexes on subpaths. Only allowed for subdocuments and subdocument arrays. */
     excludeIndexes?: boolean;
diff --git a/lib/schema.js b/lib/schema.js
index 9130e219b5d..c740902d2fd 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -1555,7 +1555,7 @@ Schema.prototype.static = function(name, fn) {
  *
  * @param {Object} fields
  * @param {Object} [options] Options to pass to [MongoDB driver's `createIndex()` function](http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#createIndex)
- * @param {String} [options.expires=null] Mongoose-specific syntactic sugar, uses [ms](https://www.npmjs.com/package/ms) to convert `expires` option into seconds for the `expireAfterSeconds` in the above link.
+ * @param {String | number} [options.expires=null] Mongoose-specific syntactic sugar, uses [ms](https://www.npmjs.com/package/ms) to convert `expires` option into seconds for the `expireAfterSeconds` in the above link.
  * @api public
  */
 

From 332268d66462328f8051f7b4587f2cbaf80d1201 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Aug 2021 20:06:10 -0400
Subject: [PATCH 2283/2348] fix(index.d.ts): add `Query#model` property to ts
 bindings

Fix #10531
---
 index.d.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index d845edf528d..cd4aed9bae9 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2332,6 +2332,9 @@ declare module 'mongoose' {
     mod(val: Array<number>): this;
     mod(path: string, val: Array<number>): this;
 
+    /** The model this query was created from */
+    model: typeof Model;
+
     /**
      * Getter/setter around the current mongoose-specific options for this query
      * Below are the current Mongoose-specific options.

From 2eed9404a4a6d81f3156e12b68e31bf081ebd569 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 10 Aug 2021 20:06:47 -0400
Subject: [PATCH 2284/2348] docs(query): add `Query#model` to docs re: #10531

---
 lib/query.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/lib/query.js b/lib/query.js
index af16622fc84..4eb5b4a4cde 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -5543,6 +5543,22 @@ Query.prototype.selectedExclusively = function selectedExclusively() {
   return isExclusive(this._fields);
 };
 
+/**
+ * The model this query is associated with.
+ *
+ * #### Example:
+ *
+ *     const q = MyModel.find();
+ *     q.model === MyModel; // true
+ *
+ * @api public
+ * @property model
+ * @memberOf Query
+ * @instance
+ */
+
+Query.prototype.model;
+
 /*!
  * Export
  */

From fefebb35065f7d85850b77656484d538aa4d612d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 12:49:31 -0400
Subject: [PATCH 2285/2348] perf(index.d.ts): loosen up restrictions on
 `ModelType` generic for Schema for a ~50% perf improvement when compiling
 TypeScript and using intellisense

Re: #10349
Fix #10536
Re: #10515
---
 index.d.ts                  | 49 +++++++++++++++++++++++--------------
 test/typescript/document.ts | 22 +++++++++++++++++
 2 files changed, 52 insertions(+), 19 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index d845edf528d..7f0360421c0 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -103,7 +103,13 @@ declare module 'mongoose' {
   export function model<T>(name: string, schema?: Schema<any>, collection?: string, skipInit?: boolean): Model<T>;
   export function model<T, U extends Model<T, TQueryHelpers, any>, TQueryHelpers = {}>(
     name: string,
-    schema?: Schema<T, U>,
+    schema?: Schema<T, U, TQueryHelpers>,
+    collection?: string,
+    skipInit?: boolean
+  ): U;
+  export function model<T, U extends Model<T, TQueryHelpers, any>, TQueryHelpers = {}>(
+    name: string,
+    schema?: Schema<any>,
     collection?: string,
     skipInit?: boolean
   ): U;
@@ -377,13 +383,19 @@ declare module 'mongoose' {
     models: { [index: string]: Model<any> };
 
     /** Defines or retrieves a model. */
-    model<T>(name: string, schema?: Schema<T>, collection?: string): Model<T>;
+    model<T>(name: string, schema?: Schema<any>, collection?: string): Model<T>;
     model<T, U extends Model<T, TQueryHelpers, any>, TQueryHelpers = {}>(
       name: string,
       schema?: Schema<T, U, TQueryHelpers>,
       collection?: string,
       skipInit?: boolean
     ): U;
+    model<T, U extends Model<T, TQueryHelpers, any>, TQueryHelpers = {}>(
+      name: string,
+      schema?: Schema<any>,
+      collection?: string,
+      skipInit?: boolean
+    ): U;
 
     /** Returns an array of model names created on this connection. */
     modelNames(): Array<string>;
@@ -750,8 +762,8 @@ declare module 'mongoose' {
 
   interface AcceptsDiscriminator {
     /** Adds a discriminator type. */
-    discriminator<D>(name: string | number, schema: Schema<D>, value?: string | number | ObjectId): Model<D>;
-    discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
+    discriminator<D>(name: string | number, schema: Schema, value?: string | number | ObjectId): Model<D>;
+    discriminator<T, U>(name: string | number, schema: Schema<T, U>, value?: string | number | ObjectId): U;
   }
 
   type AnyKeys<T> = { [P in keyof T]?: T[P] | any };
@@ -1243,7 +1255,6 @@ declare module 'mongoose' {
   type SchemaPreOptions = { document?: boolean, query?: boolean };
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
-  type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
 
   type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
@@ -1251,7 +1262,7 @@ declare module 'mongoose' {
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;
   type ErrorHandlingMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, err: NativeError, res: ResType, next: (err?: CallbackError) => void) => void;
 
-  class Schema<DocType = Document, M extends Model<DocType, any, any> = Model<any, any, any>, SchemaDefinitionType = undefined, TInstanceMethods = ExtractMethods<M>> extends events.EventEmitter {
+  class Schema<DocType = Document, M = Model<DocType, any, any>, SchemaDefinitionType = undefined, TInstanceMethods = {}> extends events.EventEmitter {
     /**
      * Create a new schema
      */
@@ -1329,8 +1340,8 @@ declare module 'mongoose' {
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: PostMiddlewareFunction<T, Array<any>>): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T, Array<any>>): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: PostMiddlewareFunction<T>): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
+    post<T = M>(method: 'insertMany' | RegExp, fn: PostMiddlewareFunction<T>): this;
+    post<T = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: PostMiddlewareFunction<T>): this;
 
     post<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
     post<T = EnforceDocument<DocType, TInstanceMethods>>(method: MongooseDocumentMiddleware | MongooseDocumentMiddleware[] | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
@@ -1338,8 +1349,8 @@ declare module 'mongoose' {
     post<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
     post<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T, Array<any>>): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
-    post<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T = M>(method: 'insertMany' | RegExp, fn: ErrorHandlingMiddlewareFunction<T>): this;
+    post<T = M>(method: 'insertMany' | RegExp, options: SchemaPostOptions, fn: ErrorHandlingMiddlewareFunction<T>): this;
 
     /** Defines a pre hook for the model. */
     pre<T = EnforceDocument<DocType, TInstanceMethods>>(method: 'save', fn: PreSaveMiddlewareFunction<T>): this;
@@ -1349,11 +1360,11 @@ declare module 'mongoose' {
     pre<T extends Query<any, any> = Query<any, any>>(method: MongooseQueryMiddleware | MongooseQueryMiddleware[] | string | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, fn: PreMiddlewareFunction<T>): this;
     pre<T extends Aggregate<any> = Aggregate<any>>(method: 'aggregate' | RegExp, options: SchemaPreOptions, fn: PreMiddlewareFunction<T>): this;
-    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
-    pre<T extends Model<DocType> = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
+    pre<T = M>(method: 'insertMany' | RegExp, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
+    pre<T = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: <T extends QueryWithHelpers<any, EnforceDocument<DocType, TInstanceMethods>, ExtractQueryHelpers<M>> = QueryWithHelpers<any, EnforceDocument<DocType, ExtractMethods<M>>, ExtractQueryHelpers<M>>>(this: T, ...args: any[]) => any };
+    query: { [name: string]: Function };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
@@ -1840,8 +1851,8 @@ declare module 'mongoose' {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator<D>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
+        discriminator<D>(name: string | number, schema: Schema, value?: string): Model<D>;
+        discriminator<T, U>(name: string | number, schema: Schema<T, U>, value?: string): U;
 
         /**
          * Adds an enum validator if this is an array of strings or numbers. Equivalent to
@@ -1897,8 +1908,8 @@ declare module 'mongoose' {
 
         static options: { castNonArrays: boolean; };
 
-        discriminator<D>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
+        discriminator<D>(name: string | number, schema: Schema, value?: string): Model<D>;
+        discriminator<T, U>(name: string | number, schema: Schema<T, U>, value?: string): U;
 
         /** The schema used for documents in this array */
         schema: Schema;
@@ -1943,8 +1954,8 @@ declare module 'mongoose' {
         /** The document's schema */
         schema: Schema;
 
-        discriminator<D>(name: string | number, schema: Schema<D>, value?: string): Model<D>;
-        discriminator<T, U extends Model<T>>(name: string | number, schema: Schema<T, U>, value?: string): U;
+        discriminator<D>(name: string | number, schema: Schema, value?: string): Model<D>;
+        discriminator<T, U>(name: string | number, schema: Schema<T, U>, value?: string): U;
       }
 
       class String extends SchemaType {
diff --git a/test/typescript/document.ts b/test/typescript/document.ts
index 8abde523a7d..4df05d386ed 100644
--- a/test/typescript/document.ts
+++ b/test/typescript/document.ts
@@ -36,4 +36,26 @@ void async function run() {
 
 function gh10526<U extends ITest>(arg1: Model<U>) {
   const t = new arg1({ name: 'hello' });
+}
+
+function testMethods(): void {
+  interface IUser {
+    first: string;
+    last: string;
+  }
+
+  interface IUserMethods {
+    fullName(): string;
+  }
+
+  type User = Model<IUser, {}, IUserMethods>
+
+  const schema = new Schema<IUser, User>({ first: String, last: String });
+  schema.methods.fullName = function(): string {
+    return this.first + ' ' + this.last;
+  };
+  const UserModel = model<IUser, User>('User', schema);
+
+  const doc = new UserModel({ first: 'test', last: 'test' });
+  doc.fullName().toUpperCase();
 }
\ No newline at end of file

From 540a82022e1488c67f58fa909e78ce6978a1488e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 13:56:05 -0400
Subject: [PATCH 2286/2348] fix(index.d.ts): allow using SchemaTypeOptions with
 array of raw document interfaces

Fix #10537
---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index fddf97b9cc5..a3b46662fd2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1591,7 +1591,7 @@ declare module 'mongoose' {
     type?:
       T extends string | number | boolean | NativeDate | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema<any, any> ? T :
-      T extends object[] ? (Schema<Document<Unpacked<T>>>[] | ReadonlyArray<Schema<Document<Unpacked<T>>>> | Schema<Document & Unpacked<T>>[] | ReadonlyArray<Schema<Document & Unpacked<T>>>) :
+      T extends object[] ? (Schema<Unpacked<T>>[] | ReadonlyArray<Schema<Unpacked<T>>> | Schema<Document & Unpacked<T>>[] | ReadonlyArray<Schema<Document & Unpacked<T>>>) :
       T extends string[] ? (SchemaDefinitionWithBuiltInClass<string>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<string>>) :
       T extends number[] ? (SchemaDefinitionWithBuiltInClass<number>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<number>>) :
       T extends boolean[] ? (SchemaDefinitionWithBuiltInClass<boolean>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<boolean>>) :

From 2a608e3c7a06c1104d6147e896314b935b2cdab2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:12:24 -0400
Subject: [PATCH 2287/2348] style: fix lint

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 6b89bc0158b..6bfe1675dcf 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1259,7 +1259,7 @@ declare module 'mongoose' {
 
   type IndexDirection = 1 | -1 | '2d' | '2dsphere' | 'geoHaystack' | 'hashed' | 'text';
   type IndexDefinition = Record<string, IndexDirection>;
-  
+
   type PreMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void) => void | Promise<void>;
   type PreSaveMiddlewareFunction<T> = (this: T, next: (err?: CallbackError) => void, opts: SaveOptions) => void | Promise<void>;
   type PostMiddlewareFunction<ThisType, ResType = any> = (this: ThisType, res: ResType, next: (err?: CallbackError) => void) => void | Promise<void>;

From 7e398a948c03756879816d5478cfd71fb28d2a59 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:21:26 -0400
Subject: [PATCH 2288/2348] test(typescript): add coverage for #10562

---
 test/typescript/schema.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 7bcf2081ebf..6057d994f2f 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -66,6 +66,10 @@ const movieSchema = new Schema<Document<Movie>, Model<Document<Movie>>, Movie>({
   }
 });
 
+movieSchema.index({ status: 1, 'actors.name': 1 });
+movieSchema.index({ title: 'text' });
+movieSchema.index({ rating: -1 });
+
 // Using `SchemaDefinition`
 interface IProfile { age: number; }
 interface ProfileDoc extends Document, IProfile {}

From 100101b3bf4e1ae8d122d806b75190244e88c19a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:23:24 -0400
Subject: [PATCH 2289/2348] fix: apply code review suggestions re: loose typing
 to `push()` and remove unused code

---
 index.d.ts | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 43deb904209..d9119c7cf2b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1904,7 +1904,7 @@ declare module 'mongoose' {
 
         /** Sets a maximum number validator. */
         max(value: number, message: string): this;
-
+\
         /** Sets a minimum number validator. */
         min(value: number, message: string): this;
       }
@@ -1957,7 +1957,6 @@ declare module 'mongoose' {
   }
 
   namespace Types {
-	type OmitDocumentTypes<T> = T extends Document ? Omit<T, keyof Document> : T
     class Array<T> extends global.Array<T> {
       /** Pops the array atomically at most one time per document `save()`. */
       $pop(): T;
@@ -1974,7 +1973,7 @@ declare module 'mongoose' {
       nonAtomicPush(...args: Array<AnyKeys<T> & AnyObject>): number;
 
       /** Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking. */
-      push(...args: T[]): number;
+      push(...args: (AnyKeys<T> & AnyObject)[]): number;
 
       /**
        * Pulls items from the array atomically. Equality is determined by casting

From 2f57e768a691edacb6590d3ff51b0adcfff28481 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:28:27 -0400
Subject: [PATCH 2290/2348] fix: fix build

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index d9119c7cf2b..33777870cdd 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1973,7 +1973,7 @@ declare module 'mongoose' {
       nonAtomicPush(...args: Array<AnyKeys<T> & AnyObject>): number;
 
       /** Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking. */
-      push(...args: (AnyKeys<T> & AnyObject)[]): number;
+      push(...args: Array<AnyKeys<T> & AnyObject>): number;
 
       /**
        * Pulls items from the array atomically. Equality is determined by casting

From 711ded8da2f83eda0e446484bbeb9ba3fd0b01c9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:29:02 -0400
Subject: [PATCH 2291/2348] fix: fix build

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 33777870cdd..7b87dd80423 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1904,7 +1904,7 @@ declare module 'mongoose' {
 
         /** Sets a maximum number validator. */
         max(value: number, message: string): this;
-\
+
         /** Sets a minimum number validator. */
         min(value: number, message: string): this;
       }

From fa1c43c8a46a4e47c69750c931c73fc656e3d475 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:31:08 -0400
Subject: [PATCH 2292/2348] fix: correct types

---
 index.d.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 7b87dd80423..f4f0ac912b4 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1970,10 +1970,10 @@ declare module 'mongoose' {
       isMongooseArray: true;
 
       /** Pushes items to the array non-atomically. */
-      nonAtomicPush(...args: Array<AnyKeys<T> & AnyObject>): number;
+      nonAtomicPush(...args: any[]): number;
 
       /** Wraps [`Array#push`](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/push) with proper change tracking. */
-      push(...args: Array<AnyKeys<T> & AnyObject>): number;
+      push(...args: any[]): number;
 
       /**
        * Pulls items from the array atomically. Equality is determined by casting
@@ -2023,7 +2023,7 @@ declare module 'mongoose' {
       /** Searches array items for the first document with a matching _id. */
       id(id: any): T | null;
 
-      push(...args: Omit<T, keyof Document>[]): number;
+      push(...args: Array<AnyKeys<T> & AnyObject>): number;
     }
 
     class EmbeddedDocument extends Document {

From 22a3570125037dcc650665d894cc6be53373d409 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 14:56:06 -0400
Subject: [PATCH 2293/2348] fix: fix build again

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index f4f0ac912b4..3a5c56f042b 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2023,7 +2023,7 @@ declare module 'mongoose' {
       /** Searches array items for the first document with a matching _id. */
       id(id: any): T | null;
 
-      push(...args: Array<AnyKeys<T> & AnyObject>): number;
+      push(...args: (AnyKeys<T> & AnyObject)[]): number;
     }
 
     class EmbeddedDocument extends Document {

From ec41d2222e4692169d15c6f0a968c71ed256fd56 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 11 Aug 2021 15:17:21 -0400
Subject: [PATCH 2294/2348] chore: release 5.13.7

---
 History.md   | 11 +++++++++++
 package.json |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 66d22d57032..da3710c0947 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,14 @@
+5.13.7 / 2021-08-11
+===================
+ * perf(index.d.ts): loosen up restrictions on ModelType generic for Schema for a ~50% perf improvement when compiling TypeScript and using intellisense #10536 #10515 #10349
+ * fix(index.d.ts): fix broken `Schema#index()` types #10562 [JaredReisinger](https://github.com/JaredReisinger)
+ * fix(index.d.ts): allow using SchemaTypeOptions with array of raw document interfaces #10537
+ * fix(index.d.ts): define IndexOptions in terms of mongodb.IndexOptions #10563 [JaredReisinger](https://github.com/JaredReisinger)
+ * fix(index.d.ts): improve intellisense for DocumentArray `push()` #10546
+ * fix(index.d.ts): correct type for expires #10529
+ * fix(index.d.ts): add Query#model property to ts bindings #10531
+ * refactor(index.d.ts): make callbacks use the new Callback and CallbackWithoutResult types #10550 [thiagokisaki](https://github.com/thiagokisaki)
+
 5.13.6 / 2021-08-09
 ===================
  * fix: upgrade mongodb driver -> 3.6.11 #10543 [maon-fp](https://github.com/maon-fp)
diff --git a/package.json b/package.json
index 95d51dc2ce8..385ab217308 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.6",
+  "version": "5.13.7",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 79d1a8e1cba1b1b0306d6e2f2aa2a1a8384c2736 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Aug 2021 14:41:24 -0400
Subject: [PATCH 2295/2348] fix(index.d.ts): correct value of `this` for custom
 query helper methods

Fix #10545
---
 index.d.ts                   | 5 +++--
 test/typescript/main.test.js | 3 ++-
 test/typescript/queries.ts   | 8 +++++++-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 638fe56da4e..b7c11aebd85 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1256,6 +1256,7 @@ declare module 'mongoose' {
   type SchemaPostOptions = { document?: boolean, query?: boolean };
 
   type ExtractMethods<M> = M extends Model<any, any, infer TMethods> ? TMethods : {};
+  type ExtractQueryHelpers<M> = M extends Model<any, infer TQueryHelpers> ? TQueryHelpers : {};
 
   type IndexDirection = 1 | -1 | '2d' | '2dsphere' | 'geoHaystack' | 'hashed' | 'text';
   type IndexDefinition = Record<string, IndexDirection>;
@@ -1367,7 +1368,7 @@ declare module 'mongoose' {
     pre<T = M>(method: 'insertMany' | RegExp, options: SchemaPreOptions, fn: (this: T, next: (err?: CallbackError) => void, docs: any | Array<any>) => void | Promise<void>): this;
 
     /** Object of currently defined query helpers on this schema. */
-    query: { [name: string]: Function };
+    query: { [name: string]: (this: QueryWithHelpers<any, DocType, ExtractQueryHelpers<M>>, ...args: any[]) => any };
 
     /** Adds a method call to the queue. */
     queue(name: string, args: any[]): this;
@@ -1599,7 +1600,7 @@ declare module 'mongoose' {
       T extends number[] ? (SchemaDefinitionWithBuiltInClass<number>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<number>>) :
       T extends boolean[] ? (SchemaDefinitionWithBuiltInClass<boolean>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<boolean>>) :
       T extends Function[] ? (SchemaDefinitionWithBuiltInClass<Function>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<Function>>) :
-      T | typeof SchemaType | Schema<any, any>;
+      T | typeof SchemaType | Schema<any, any, any, any>;
 
     /** Defines a virtual with the given name that gets/sets this path. */
     alias?: string;
diff --git a/test/typescript/main.test.js b/test/typescript/main.test.js
index da0e1afe237..7806e97fd82 100644
--- a/test/typescript/main.test.js
+++ b/test/typescript/main.test.js
@@ -52,7 +52,8 @@ describe('typescript syntax', function() {
     if (process.env.D && errors.length) {
       console.log(errors);
     }
-    assert.equal(errors.length, 0);
+    assert.equal(errors.length, 1);
+    assert.ok(errors[0].messageText.includes('notAQueryHelper'), errors[0].messageText);
   });
 
   it('create', function() {
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index fcd1de717de..b832e212815 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,6 +1,7 @@
 import { Schema, model, Document, Types, Query, Model, QueryWithHelpers } from 'mongoose';
 
 interface QueryHelpers {
+  _byName(this: QueryWithHelpers<any, ITest, QueryHelpers>, name: string): QueryWithHelpers<Array<ITest>, ITest, QueryHelpers>;
   byName(name: string): QueryWithHelpers<Array<ITest>, ITest, QueryHelpers>;
 }
 
@@ -11,10 +12,15 @@ const schema: Schema<ITest, Model<ITest, QueryHelpers>> = new Schema({
   endDate: Date
 });
 
-schema.query.byName = function(name: string): Query<any, ITest, QueryHelpers> & QueryHelpers {
+schema.query._byName = function(name: string): QueryWithHelpers<any, ITest> {
   return this.find({ name });
 };
 
+schema.query.byName = function(name: string): QueryWithHelpers<any, ITest> {
+  this.notAQueryHelper();
+  return this._byName(name);
+};
+
 interface ISubdoc extends Document {
   id?: number;
   tags?: string[];

From b31fd51f51d49189894851411f11ef5aef4c4edf Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Aug 2021 15:26:19 -0400
Subject: [PATCH 2296/2348] fix(model): check for `code` instead of `codeName`
 when checking for existing collections for backwards compat with MongoDB 3.2

Fix #10420
---
 lib/model.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/model.js b/lib/model.js
index 766c84a7c82..412803aca9f 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1348,9 +1348,9 @@ Model.createCollection = function createCollection(options, callback) {
   return this.db.base._promiseOrCallback(callback, cb => {
     cb = this.$wrapCallback(cb);
 
-    this.db.createCollection(this.$__collection.collectionName, options, utils.tick((error) => {
-      if (error != null && error.codeName !== 'NamespaceExists') {
-        return cb(error);
+    this.db.createCollection(this.$__collection.collectionName, options, utils.tick((err) => {
+      if (err != null && (err.name !== 'MongoError' || err.code !== 48)) {
+        return cb(err);
       }
       this.$__collection = this.db.collection(this.$__collection.collectionName, options);
       cb(null, this.$__collection);
@@ -1391,7 +1391,7 @@ Model.syncIndexes = function syncIndexes(options, callback) {
     cb = this.$wrapCallback(cb);
 
     this.createCollection(err => {
-      if (err != null && err.codeName !== 'NamespaceExists') {
+      if (err != null && (err.name !== 'MongoError' || err.code !== 48)) {
         return cb(err);
       }
       this.cleanIndexes((err, dropped) => {

From 283d43faaa31a9c9b77bba5cd80caea901c1f411 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Aug 2021 17:04:43 -0400
Subject: [PATCH 2297/2348] test(populate): repro #10552

---
 test/model.populate.test.js | 51 +++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 19a86ce4030..57bb9ed696c 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -4500,6 +4500,57 @@ describe('model: populate:', function() {
           catch(done);
       });
 
+      it('in embedded array with sort (gh-10552)', function() {
+        const AppMenuItemSchema = new Schema({
+          appId: 'ObjectId',
+          moduleId: Number,
+          title: String,
+          parent: {
+            type: mongoose.ObjectId,
+            ref: 'AppMenuItem'
+          },
+          order: Number
+        });
+
+        const moduleSchema = new Schema({
+          _id: Number,
+          title: { type: String },
+          hidden: { type: Boolean }
+        });
+
+        moduleSchema.virtual('menu', {
+          ref: 'Test1',
+          localField: '_id',
+          foreignField: 'moduleId',
+          options: { sort: { title: 1 } }
+        });
+
+        const appSchema = new Schema({
+          modules: [moduleSchema]
+        });
+
+        const App = db.model('Test', appSchema);
+        const AppMenuItem = db.model('Test1', AppMenuItemSchema);
+
+        return co(function*() {
+          let app = yield App.create({ modules: [{ _id: 1, title: 'File' }, { _id: 2, title: 'Preferences' }] });
+          yield AppMenuItem.create([
+            { title: 'Save', moduleId: 1 },
+            { title: 'Save As', moduleId: 1 },
+            { title: 'Undo', moduleId: 2 },
+            { title: 'Redo', moduleId: 2 },
+          ]);
+
+          app = yield App.findById(app).populate('modules.menu');
+          app = app.toObject({ virtuals: true });
+
+          assert.equal(app.modules.length, 2);
+          assert.equal(app.modules[0].menu.length, 2);
+          assert.deepEqual(app.modules[0].menu.map(i => i.title), ['Save', 'Save As']);
+          assert.deepEqual(app.modules[1].menu.map(i => i.title), ['Redo', 'Undo']);
+        });
+      });
+
       it('justOne option (gh-4263)', function(done) {
         const PersonSchema = new Schema({
           name: String,

From 6b9259998a95c2552d412f9bd297125764db9cf8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Aug 2021 17:05:02 -0400
Subject: [PATCH 2298/2348] fix(populate): handle populating subdoc array
 virtual with sort

Fix #10552
---
 lib/helpers/populate/assignRawDocsToIdStructure.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/helpers/populate/assignRawDocsToIdStructure.js b/lib/helpers/populate/assignRawDocsToIdStructure.js
index 843c148373e..5682143a84e 100644
--- a/lib/helpers/populate/assignRawDocsToIdStructure.js
+++ b/lib/helpers/populate/assignRawDocsToIdStructure.js
@@ -69,7 +69,12 @@ function assignRawDocsToIdStructure(rawIds, resultDocs, resultOrder, options, re
     if (recursed) {
       if (doc) {
         if (sorting) {
-          newOrder[resultOrder[sid]] = doc;
+          const _resultOrder = resultOrder[sid];
+          if (Array.isArray(_resultOrder) && Array.isArray(doc) && _resultOrder.length === doc.length) {
+            newOrder.push(doc);
+          } else {
+            newOrder[_resultOrder] = doc;
+          }
         } else {
           newOrder.push(doc);
         }

From fca0627566b961d3db9616a10ee3c80121cbb0e2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 17 Aug 2021 17:39:52 -0400
Subject: [PATCH 2299/2348] style: fix lint

---
 test/model.populate.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 57bb9ed696c..6bedbc3e623 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -4538,7 +4538,7 @@ describe('model: populate:', function() {
             { title: 'Save', moduleId: 1 },
             { title: 'Save As', moduleId: 1 },
             { title: 'Undo', moduleId: 2 },
-            { title: 'Redo', moduleId: 2 },
+            { title: 'Redo', moduleId: 2 }
           ]);
 
           app = yield App.findById(app).populate('modules.menu');

From e90aab12bf3ced0d0ac7b5994a0530f77fc9f8e5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 19 Aug 2021 16:55:01 -0400
Subject: [PATCH 2300/2348] docs(History): make a note about #10555

Fix #10576
---
 History.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/History.md b/History.md
index da3710c0947..451ff07fb60 100644
--- a/History.md
+++ b/History.md
@@ -15,6 +15,7 @@
  * fix(schema): throw more helpful error when defining a document array using a schema from a different copy of the Mongoose module #10453
  * fix: add explicit check on constructor property to avoid throwing an error when checking objects with null prototypes #10512
  * fix(cursor): make sure to clear stack every 1000 docs when calling `next()` to avoid stack overflow with large batch size #10449
+ * fix(index.d.ts): improve types of Schema#(g|s)et #10555 [thiagokisaki](https://github.com/thiagokisaki)
  * fix(index.d.ts): allow calling new Model(...) with generic Model param #10526
  * fix(index.d.ts): update type declarations of Schema.index method #10538 #10530 [Raader](https://github.com/Raader)
  * fix(index.d.ts): add useNewUrlParser and useUnifiedTopology to ConnectOptions #10500

From 6c362631a2c7680737723dbc0c91262286a7b164 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sat, 21 Aug 2021 14:33:57 -0400
Subject: [PATCH 2301/2348] fix(index.d.ts): allow strings for ObjectIds in
 nested properties

Fix #10573
---
 index.d.ts                 | 12 ++++++++----
 test/typescript/queries.ts |  5 ++++-
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index b7c11aebd85..a542e62f81a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1270,10 +1270,10 @@ declare module 'mongoose' {
     /**
      * Create a new schema
      */
-    constructor(definition?: SchemaDefinition<DocumentDefinition<SchemaDefinitionType>>, options?: SchemaOptions);
+    constructor(definition?: SchemaDefinition<LeanDocument<SchemaDefinitionType>>, options?: SchemaOptions);
 
     /** Adds key path / schema type pairs to this schema. */
-    add(obj: SchemaDefinition<DocumentDefinition<SchemaDefinitionType>> | Schema, prefix?: string): this;
+    add(obj: SchemaDefinition<LeanDocument<SchemaDefinitionType>> | Schema, prefix?: string): this;
 
     /**
      * Array of child schemas (from document arrays and single nested subdocs)
@@ -2587,8 +2587,12 @@ declare module 'mongoose' {
   export type UpdateQuery<T> = (_UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>);
 
   type _AllowStringsForIds<T> = {
-    [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never] ? T[K] : T[K] | string;
-  };
+    [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never]
+      ? T[K] extends TreatAsPrimitives
+        ? T[K]
+        : _AllowStringsForIds<T[K]>
+      : T[K] | string;
+    };
   export type DocumentDefinition<T> = _AllowStringsForIds<LeanDocument<T>>;
 
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index b832e212815..6f56f775558 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -8,7 +8,7 @@ interface QueryHelpers {
 const schema: Schema<ITest, Model<ITest, QueryHelpers>> = new Schema({
   name: { type: 'String' },
   tags: [String],
-  docs: [{ nested: { id: Number, tags: [String] } }],
+  docs: [{ _id: 'ObjectId', id: Number, tags: [String] }],
   endDate: Date
 });
 
@@ -22,6 +22,7 @@ schema.query.byName = function(name: string): QueryWithHelpers<any, ITest> {
 };
 
 interface ISubdoc extends Document {
+  myId?: Types.ObjectId;
   id?: number;
   tags?: string[];
 }
@@ -89,6 +90,8 @@ Test.findOneAndUpdate({ name: 'test' }, [{ $set: { endDate: true } }]);
 
 Test.findByIdAndUpdate({ name: 'test' }, { name: 'test2' }, (err, doc) => console.log(doc));
 
+Test.findOneAndUpdate({ name: 'test' }, { 'docs.0.myId': '0'.repeat(24) });
+
 const query: Query<ITest | null, ITest> = Test.findOne();
 query instanceof Query;
 

From 57e729bc9b51bb8f27a521ee1c83eb74422fe3ad Mon Sep 17 00:00:00 2001
From: Osman Akol <osmanakol@outlook.com>
Date: Sun, 22 Aug 2021 15:29:02 +0300
Subject: [PATCH 2302/2348] allow QueryOptions populate parameter use
 PopulateOptions

---
 index.d.ts                 |  2 +-
 test/typescript/queries.ts | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index a542e62f81a..38d87dd7a30 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1079,7 +1079,7 @@ declare module 'mongoose' {
     omitUndefined?: boolean;
     overwrite?: boolean;
     overwriteDiscriminatorKey?: boolean;
-    populate?: string;
+    populate?: string | string[] | PopulateOptions | PopulateOptions[];
     projection?: any;
     /**
      * if true, returns the raw result from the MongoDB driver
diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 6f56f775558..5d5f9c07b58 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -1,13 +1,18 @@
-import { Schema, model, Document, Types, Query, Model, QueryWithHelpers } from 'mongoose';
+import { Schema, model, Document, Types, Query, Model, QueryWithHelpers, PopulatedDoc } from 'mongoose';
+import { ObjectId } from 'mongodb';
 
 interface QueryHelpers {
   _byName(this: QueryWithHelpers<any, ITest, QueryHelpers>, name: string): QueryWithHelpers<Array<ITest>, ITest, QueryHelpers>;
   byName(name: string): QueryWithHelpers<Array<ITest>, ITest, QueryHelpers>;
 }
 
+const childSchema: Schema = new Schema({ name: String });
+const ChildModel = model<Child>('Child', childSchema);
+
 const schema: Schema<ITest, Model<ITest, QueryHelpers>> = new Schema({
   name: { type: 'String' },
   tags: [String],
+  child: { type: 'ObjectId', ref: 'Child' },
   docs: [{ _id: 'ObjectId', id: Number, tags: [String] }],
   endDate: Date
 });
@@ -21,6 +26,9 @@ schema.query.byName = function(name: string): QueryWithHelpers<any, ITest> {
   return this._byName(name);
 };
 
+interface Child {
+  name: string;
+}
 interface ISubdoc extends Document {
   myId?: Types.ObjectId;
   id?: number;
@@ -31,6 +39,7 @@ interface ITest extends Document {
   name?: string;
   age?: number;
   parent?: Types.ObjectId;
+  child?: PopulatedDoc<Child & Document<ObjectId>>,
   tags?: string[];
   docs?: ISubdoc[];
   endDate?: Date;
@@ -38,6 +47,8 @@ interface ITest extends Document {
 
 const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
 
+Test.find({}, {}, {populate:{path:"child", model:ChildModel, match:true}}).exec().then((res: Array<ITest>) => console.log(res))
+
 Test.find().byName('test').byName('test2').orFail().exec().then(console.log);
 
 Test.count({ name: /Test/ }).exec().then((res: number) => console.log(res));

From 2871c1bff9dd4ccf5c642991bee599782f30f9fb Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Aug 2021 11:18:22 -0400
Subject: [PATCH 2303/2348] style: fix lint

---
 test/typescript/queries.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/typescript/queries.ts b/test/typescript/queries.ts
index 5d5f9c07b58..15c40232c08 100644
--- a/test/typescript/queries.ts
+++ b/test/typescript/queries.ts
@@ -47,7 +47,7 @@ interface ITest extends Document {
 
 const Test = model<ITest, Model<ITest, QueryHelpers>>('Test', schema);
 
-Test.find({}, {}, {populate:{path:"child", model:ChildModel, match:true}}).exec().then((res: Array<ITest>) => console.log(res))
+Test.find({}, {}, { populate: { path: 'child', model: ChildModel, match: true } }).exec().then((res: Array<ITest>) => console.log(res));
 
 Test.find().byName('test').byName('test2').orFail().exec().then(console.log);
 

From 6122f4bca9c5376dc23124cb2b53d6331fae7a1b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Aug 2021 11:22:28 -0400
Subject: [PATCH 2304/2348] docs(api): add `Document#$where` to API docs

Fix #10583
---
 index.d.ts      |  2 +-
 lib/document.js | 22 ++++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 38d87dd7a30..2cbdbe62f9e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -574,7 +574,7 @@ declare module 'mongoose' {
     $set(path: string, val: any, type: any, options?: any): this;
     $set(value: any): this;
 
-    /** Additional properties to attach to the query when calling `save()` and `isNew` is false. */
+    /** Set this property to add additional query filters when Mongoose saves this document and `isNew` is false. */
     $where: Record<string, unknown>;
 
     /** If this is a discriminator model, `baseModelName` is the name of the base model. */
diff --git a/lib/document.js b/lib/document.js
index ef31c2e5288..c081a17335d 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -265,6 +265,28 @@ Object.defineProperty(Document.prototype, '$locals', {
 
 Document.prototype.isNew;
 
+/**
+ * Set this property to add additional query filters when Mongoose saves this document and `isNew` is false.
+ *
+ * ####Example:
+ *
+ *     // Make sure `save()` never updates a soft deleted document.
+ *     schema.pre('save', function() {
+ *       this.$where = { isDeleted: false };
+ *     });
+ *
+ * @api public
+ * @property $where
+ * @memberOf Document
+ * @instance
+ */
+
+Object.defineProperty(Document.prototype, '$where', {
+  configurable: false,
+  enumerable: false,
+  writable: true
+});
+
 /**
  * The string version of this documents _id.
  *

From 5c0140c7db18f2cd800011821c85e2a8617ffff8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Aug 2021 11:31:51 -0400
Subject: [PATCH 2305/2348] fix(index.d.ts): add `match` to
 `VirtualTypeOptions.options`

Fix #8479
---
 index.d.ts                  | 2 +-
 test/typescript/virtuals.ts | 9 +++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 2cbdbe62f9e..c902fba0d80 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1823,7 +1823,7 @@ declare module 'mongoose' {
     perDocumentLimit?: number;
 
     /** Additional options like `limit` and `lean`. */
-    options?: QueryOptions;
+    options?: QueryOptions & { match?: AnyObject };
 
     /** Additional options for plugins */
     [extra: string]: any;
diff --git a/test/typescript/virtuals.ts b/test/typescript/virtuals.ts
index 93b56d911ee..7f391212fd0 100644
--- a/test/typescript/virtuals.ts
+++ b/test/typescript/virtuals.ts
@@ -10,6 +10,7 @@ interface IPerson {
 
 interface IPet {
   name: string;
+  isDeleted: boolean;
   ownerId: number;
 
   owner: IPerson;
@@ -23,7 +24,8 @@ const personSchema = new Schema<IPerson & Document, Model<IPerson & Document>, I
 
 const petSchema = new Schema<IPet & Document, Model<IPet & Document>, IPet>({
   name: { type: String, required: true },
-  ownerId: { type: Number, required: true }
+  ownerId: { type: Number, required: true },
+  isDeleted: { type: Boolean, default: false }
 });
 
 // Virtual getters and setters
@@ -43,7 +45,10 @@ petSchema.virtual('owner', {
   localField: 'ownerId',
   foreignField: '_id',
   justOne: true,
-  autopopulate: true
+  autopopulate: true,
+  options: {
+    match: { isDeleted: false }
+  }
 });
 
 const Person = model('Person', personSchema);

From cb1e7872da51f6ae219ee3942bcbc6b8e125f900 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Aug 2021 11:49:30 -0400
Subject: [PATCH 2306/2348] chore: release 5.13.8

---
 History.md   | 10 ++++++++++
 package.json |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 451ff07fb60..9b79c71b4b7 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,13 @@
+5.13.8 / 2021-08-23
+===================
+ * fix(populate): handle populating subdoc array virtual with sort #10552
+ * fix(model): check for code instead of codeName when checking for existing collections for backwards compat with MongoDB 3.2 #10420
+ * fix(index.d.ts): correct value of this for custom query helper methods #10545
+ * fix(index.d.ts): allow strings for ObjectIds in nested properties #10573
+ * fix(index.d.ts): add match to VirtualTypeOptions.options #8749
+ * fix(index.d.ts): allow QueryOptions populate parameter type PopulateOptions #10587 [osmanakol](https://github.com/osmanakol)
+ * docs(api): add Document#$where to API docs #10583
+
 5.13.7 / 2021-08-11
 ===================
  * perf(index.d.ts): loosen up restrictions on ModelType generic for Schema for a ~50% perf improvement when compiling TypeScript and using intellisense #10536 #10515 #10349
diff --git a/package.json b/package.json
index 385ab217308..26c2ed6bb77 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.7",
+  "version": "5.13.8",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From bf43078dfc6736a86be71ecdf96a903420b97f82 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Aug 2021 17:01:04 -0400
Subject: [PATCH 2307/2348] fix(index.d.ts): allow specifying `weights` as an
 IndexOption

Fix #10586
---
 index.d.ts                | 3 ++-
 test/typescript/schema.ts | 4 +++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index c902fba0d80..103c8c12a2e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1748,7 +1748,8 @@ declare module 'mongoose' {
     > = PopulatedType | RawId;
 
   interface IndexOptions extends mongodb.IndexOptions {
-    expires?: number | string
+    expires?: number | string;
+    weights?: AnyObject;
   }
 
   interface ValidatorProps {
diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index 6057d994f2f..fbefc552d85 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -67,7 +67,9 @@ const movieSchema = new Schema<Document<Movie>, Model<Document<Movie>>, Movie>({
 });
 
 movieSchema.index({ status: 1, 'actors.name': 1 });
-movieSchema.index({ title: 'text' });
+movieSchema.index({ title: 'text' }, {
+  weights: { title: 10 }
+});
 movieSchema.index({ rating: -1 });
 
 // Using `SchemaDefinition`

From a803885a49cb1f0498181263e140e8b688c3e145 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 23 Aug 2021 17:02:53 -0400
Subject: [PATCH 2308/2348] test(typescript): add coverage for #10590

---
 test/typescript/schema.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/typescript/schema.ts b/test/typescript/schema.ts
index fbefc552d85..f11b3ae952c 100644
--- a/test/typescript/schema.ts
+++ b/test/typescript/schema.ts
@@ -71,6 +71,7 @@ movieSchema.index({ title: 'text' }, {
   weights: { title: 10 }
 });
 movieSchema.index({ rating: -1 });
+movieSchema.index({ title: 1 }, { unique: true });
 
 // Using `SchemaDefinition`
 interface IProfile { age: number; }

From 776fae9b5458d459eb612887f12f76e7716624c7 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 25 Aug 2021 16:57:46 -0400
Subject: [PATCH 2309/2348] docs: fix up 5.x docs navbar

---
 docs/layout.pug | 80 +++++++++++++++++++++++++------------------------
 1 file changed, 41 insertions(+), 39 deletions(-)

diff --git a/docs/layout.pug b/docs/layout.pug
index 84fb3b8a7c3..34cac146679 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -51,6 +51,8 @@ html(lang='en')
               li.pure-menu-horizontal.pure-menu-item.pure-menu-has-children.pure-menu-allow-hover.version
                 a(href="#").pure-menu-link Version #{package.version}
                 ul.pure-menu-children
+                  li.pure-menu-item
+                    a.pure-menu-link(href="/docs") Version 6.x
                   li.pure-menu-item
                     a.pure-menu-link(href="/docs/4.x") Version #{package.latest4x}
                   li.pure-menu-item
@@ -60,86 +62,86 @@ html(lang='en')
                 button#search-button-nav
                   img(src="/docs/images/search.svg")
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/index.html", class=outputUrl === '/docs/index.html' ? 'selected' : '') Quick Start
+                a.pure-menu-link(href="/docs/5.x/docs/index.html", class=outputUrl === '/docs/index.html' ? 'selected' : '') Quick Start
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/guides.html", class=outputUrl === '/docs/guides.html' ? 'selected' : '') Guides
+                a.pure-menu-link(href="/docs/5.x/docs/guides.html", class=outputUrl === '/docs/guides.html' ? 'selected' : '') Guides
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/guide.html", class=outputUrl === '/docs/schemas.html' ? 'selected' : '') Schemas
+                a.pure-menu-link(href="/docs/5.x/guide.html", class=outputUrl === '/docs/schemas.html' ? 'selected' : '') Schemas
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/schematypes.html", class=outputUrl === '/docs/schematypes.html' ? 'selected' : '') SchemaTypes
+                a.pure-menu-link(href="/docs/5.x/schematypes.html", class=outputUrl === '/docs/schematypes.html' ? 'selected' : '') SchemaTypes
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/connections.html", class=outputUrl === '/docs/connections.html' ? 'selected' : '') Connections
+                a.pure-menu-link(href="/docs/5.x/connections.html", class=outputUrl === '/docs/connections.html' ? 'selected' : '') Connections
               - if (['/docs/connections', '/docs/tutorials/ssl'].some(path => outputUrl.startsWith(path)))
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/tutorials/ssl.html", class=outputUrl === '/docs/tutorials/ssl.html' ? 'selected' : '') SSL Connections
+                  a.pure-menu-link(href="/docs/5.x/tutorials/ssl.html", class=outputUrl === '/docs/tutorials/ssl.html' ? 'selected' : '') SSL Connections
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/models.html", class=outputUrl === '/docs/models.html' ? 'selected' : '') Models
+                a.pure-menu-link(href="/docs/5.x/docs/models.html", class=outputUrl === '/docs/models.html' ? 'selected' : '') Models
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/documents.html", class=outputUrl === '/docs/documents.html' ? 'selected' : '') Documents
+                a.pure-menu-link(href="/docs/5.x/docs/documents.html", class=outputUrl === '/docs/documents.html' ? 'selected' : '') Documents
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/subdocs.html", class=outputUrl === '/docs/subdocs.html' ? 'selected' : '') Subdocuments
+                a.pure-menu-link(href="/docs/5.x/docs/subdocs.html", class=outputUrl === '/docs/subdocs.html' ? 'selected' : '') Subdocuments
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/queries.html", class=outputUrl === '/docs/queries.html' ? 'selected' : '') Queries
+                a.pure-menu-link(href="/docs/5.x/docs/queries.html", class=outputUrl === '/docs/queries.html' ? 'selected' : '') Queries
               - if (['/docs/queries', '/docs/tutorials/findoneandupdate', '/docs/tutorials/lean', '/docs/tutorials/query_casting'].some(path => outputUrl.startsWith(path)))
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/tutorials/query_casting.html", class=outputUrl === '/docs/tutorials/query_casting.html' ? 'selected' : '') Query Casting
+                  a.pure-menu-link(href="/docs/5.x/docs/tutorials/query_casting.html", class=outputUrl === '/docs/tutorials/query_casting.html' ? 'selected' : '') Query Casting
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/tutorials/findoneandupdate.html", class=outputUrl === '/docs/tutorials/findoneandupdate.html' ? 'selected' : '') findOneAndUpdate
+                  a.pure-menu-link(href="/docs/5.x/docs/tutorials/findoneandupdate.html", class=outputUrl === '/docs/tutorials/findoneandupdate.html' ? 'selected' : '') findOneAndUpdate
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/tutorials/lean.html", class=outputUrl === '/docs/tutorials/lean.html' ? 'selected' : '') The Lean Option
+                  a.pure-menu-link(href="/docs/5.x/docs/tutorials/lean.html", class=outputUrl === '/docs/tutorials/lean.html' ? 'selected' : '') The Lean Option
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/validation.html", class=outputUrl === '/docs/validation.html' ? 'selected' : '') Validation
+                a.pure-menu-link(href="/docs/5.x/docs/validation.html", class=outputUrl === '/docs/validation.html' ? 'selected' : '') Validation
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/middleware.html", class=outputUrl === '/docs/middleware.html' ? 'selected' : '') Middleware
+                a.pure-menu-link(href="/docs/5.x/docs/middleware.html", class=outputUrl === '/docs/middleware.html' ? 'selected' : '') Middleware
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/populate.html", class=outputUrl === '/docs/populate.html' ? 'selected' : '') Populate
+                a.pure-menu-link(href="/docs/5.x/docs/populate.html", class=outputUrl === '/docs/populate.html' ? 'selected' : '') Populate
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/discriminators.html", class=outputUrl === '/docs/discriminators.html' ? 'selected' : '') Discriminators
+                a.pure-menu-link(href="/docs/5.x/docs/discriminators.html", class=outputUrl === '/docs/discriminators.html' ? 'selected' : '') Discriminators
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/plugins.html", class=outputUrl === '/docs/plugins.html' ? 'selected' : '') Plugins
+                a.pure-menu-link(href="/docs/5.x/docs/plugins.html", class=outputUrl === '/docs/plugins.html' ? 'selected' : '') Plugins
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/transactions.html", class=outputUrl === '/docs/transactions.html' ? 'selected' : '') Transactions
+                a.pure-menu-link(href="/docs/5.x/docs/transactions.html", class=outputUrl === '/docs/transactions.html' ? 'selected' : '') Transactions
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/typescript.html", class=outputUrl === '/docs/typescript.html' ? 'selected' : '') TypeScript
+                a.pure-menu-link(href="/docs/5.x/docs/typescript.html", class=outputUrl === '/docs/typescript.html' ? 'selected' : '') TypeScript
               - if (outputUrl.startsWith('/docs/typescript'))
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/typescript/schemas.html", class=outputUrl === '/docs/typescript/schemas.html' ? 'selected' : '') Schemas
+                  a.pure-menu-link(href="/docs/5.x/docs/typescript/schemas.html", class=outputUrl === '/docs/typescript/schemas.html' ? 'selected' : '') Schemas
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/typescript/statics.html", class=outputUrl === '/docs/typescript/statics.html' ? 'selected' : '') Statics
+                  a.pure-menu-link(href="/docs/5.x/docs/typescript/statics.html", class=outputUrl === '/docs/typescript/statics.html' ? 'selected' : '') Statics
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/typescript/query-helpers.html", class=outputUrl === '/docs/typescript/query-helpers.html' ? 'selected' : '') Query Helpers
+                  a.pure-menu-link(href="/docs/5.x/docs/typescript/query-helpers.html", class=outputUrl === '/docs/typescript/query-helpers.html' ? 'selected' : '') Query Helpers
                 li.pure-menu-item.tertiary-item
-                  a.pure-menu-link(href="/docs/typescript/populate.html", class=outputUrl === '/docs/typescript/populate.html' ? 'selected' : '') Populate
+                  a.pure-menu-link(href="/docs/5.x/docs/typescript/populate.html", class=outputUrl === '/docs/typescript/populate.html' ? 'selected' : '') Populate
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
+                a.pure-menu-link(href="/docs/5.x/docs/api.html", class=outputUrl === '/docs/api.html' ? 'selected' : '') API
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/mongoose.html", class=outputUrl === '/docs/api/mongoose.html' ? 'selected' : '') Mongoose
+                a.pure-menu-link(href="/docs/5.x/docs/api/mongoose.html", class=outputUrl === '/docs/api/mongoose.html' ? 'selected' : '') Mongoose
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/schema.html", class=outputUrl === '/docs/api/schema.html' ? 'selected' : '') Schema
+                a.pure-menu-link(href="/docs/5.x/docs/api/schema.html", class=outputUrl === '/docs/api/schema.html' ? 'selected' : '') Schema
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/connection.html", class=outputUrl === '/docs/api/connection.html' ? 'selected' : '') Connection
+                a.pure-menu-link(href="/docs/5.x/docs/api/connection.html", class=outputUrl === '/docs/api/connection.html' ? 'selected' : '') Connection
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/document.html", class=outputUrl === '/docs/api/document.html' ? 'selected' : '') Document
+                a.pure-menu-link(href="/docs/5.x/docs/api/document.html", class=outputUrl === '/docs/api/document.html' ? 'selected' : '') Document
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/model.html", class=outputUrl === '/docs/api/model.html' ? 'selected' : '') Model
+                a.pure-menu-link(href="/docs/5.x/docs/api/model.html", class=outputUrl === '/docs/api/model.html' ? 'selected' : '') Model
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/query.html", class=outputUrl === '/docs/api/query.html' ? 'selected' : '') Query
+                a.pure-menu-link(href="/docs/5.x/docs/api/query.html", class=outputUrl === '/docs/api/query.html' ? 'selected' : '') Query
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/aggregate.html", class=outputUrl === '/docs/api/aggregate.html' ? 'selected' : '') Aggregate
+                a.pure-menu-link(href="/docs/5.x/docs/api/aggregate.html", class=outputUrl === '/docs/api/aggregate.html' ? 'selected' : '') Aggregate
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/schematype.html", class=outputUrl === '/docs/api/schematype.html' ? 'selected' : '') SchemaType
+                a.pure-menu-link(href="/docs/5.x/docs/api/schematype.html", class=outputUrl === '/docs/api/schematype.html' ? 'selected' : '') SchemaType
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/api/virtualtype.html", class=outputUrl === '/docs/api/virtualtype.html' ? 'selected' : '') VirtualType
+                a.pure-menu-link(href="/docs/5.x/docs/api/virtualtype.html", class=outputUrl === '/docs/api/virtualtype.html' ? 'selected' : '') VirtualType
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/compatibility.html", class=outputUrl === '/docs/compatibility.html' ? 'selected' : '') Version Compatibility
+                a.pure-menu-link(href="/docs/5.x/docs/compatibility.html", class=outputUrl === '/docs/compatibility.html' ? 'selected' : '') Version Compatibility
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/faq.html", class=outputUrl === '/docs/faq.html' ? 'selected' : '') FAQ
+                a.pure-menu-link(href="/docs/5.x/docs/faq.html", class=outputUrl === '/docs/faq.html' ? 'selected' : '') FAQ
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/further_reading.html", class=outputUrl === '/docs/further_reading.html' ? 'selected' : '') Further Reading
+                a.pure-menu-link(href="/docs/5.x/docs/further_reading.html", class=outputUrl === '/docs/further_reading.html' ? 'selected' : '') Further Reading
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/enterprise.html", class=outputUrl === '/docs/enterprise.html' ? 'selected' : '') For Enterprise
+                a.pure-menu-link(href="/docs/5.x/docs/enterprise.html", class=outputUrl === '/docs/enterprise.html' ? 'selected' : '') For Enterprise
               li.pure-menu-item
-                a.pure-menu-link(href="/docs/built-with-mongoose.html", , class=outputUrl === '/docs/built-with-mongoose.html' ? 'selected' : '') Built with Mongoose
+                a.pure-menu-link(href="/docs/5.x/docs/built-with-mongoose.html", , class=outputUrl === '/docs/built-with-mongoose.html' ? 'selected' : '') Built with Mongoose
             div.cpc-ad
               <script async type="text/javascript" src="//cdn.carbonads.com/carbon.js?zoneid=1673&serve=C6AILKT&placement=mongoosejscom" id="_carbonads_js"></script>
         .container

From 191678c46e7ba7a3af3776b6025c02ba705ef70c Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 25 Aug 2021 17:02:40 -0400
Subject: [PATCH 2310/2348] chore: update makefile re: #10607

---
 Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile b/Makefile
index 28333cd67e2..119f1da0263 100644
--- a/Makefile
+++ b/Makefile
@@ -45,6 +45,9 @@ copytmp:
 	cp -R ./docs/css/*.css ./tmp/docs/css
 	cp -R ./docs/js/*.js ./tmp/docs/js
 	cp -R ./docs/images/* ./tmp/docs/images
+	cp -R ./docs/api/* ./tmp/docs/api
+	cp -R ./docs/tutorials/* ./tmp/docs/tutorials
+	cp -R ./docs/typescript/* ./tmp/docs/typescript
 	cp index.html ./tmp
 
 gitreset:

From 5bf3c2996002c0808bf3b1c480b5cf8509515f16 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Wed, 25 Aug 2021 17:05:15 -0400
Subject: [PATCH 2311/2348] chore: update makefile again

---
 Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile b/Makefile
index 119f1da0263..aaff1ac2d00 100644
--- a/Makefile
+++ b/Makefile
@@ -41,6 +41,9 @@ copytmp:
 	mkdir -p ./tmp/docs/css
 	mkdir -p ./tmp/docs/js
 	mkdir -p ./tmp/docs/images
+	mkdir -p ./tmp/docs/api
+	mkdir -p ./tmp/docs/tutorials
+	mkdir -p ./tmp/docs/typescript
 	cp -R ./docs/*.html ./tmp/docs
 	cp -R ./docs/css/*.css ./tmp/docs/css
 	cp -R ./docs/js/*.js ./tmp/docs/js

From 2a3399efe037a573e38a3ce727e73fa32ee2eaa6 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 26 Aug 2021 09:51:31 -0400
Subject: [PATCH 2312/2348] docs: another layout fix for 5.x docs

Fix #10607
---
 docs/layout.pug | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/layout.pug b/docs/layout.pug
index 34cac146679..2d377c75aa7 100644
--- a/docs/layout.pug
+++ b/docs/layout.pug
@@ -66,11 +66,11 @@ html(lang='en')
               li.pure-menu-item
                 a.pure-menu-link(href="/docs/5.x/docs/guides.html", class=outputUrl === '/docs/guides.html' ? 'selected' : '') Guides
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/5.x/guide.html", class=outputUrl === '/docs/schemas.html' ? 'selected' : '') Schemas
+                a.pure-menu-link(href="/docs/5.x/docs/guide.html", class=outputUrl === '/docs/schemas.html' ? 'selected' : '') Schemas
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/5.x/schematypes.html", class=outputUrl === '/docs/schematypes.html' ? 'selected' : '') SchemaTypes
+                a.pure-menu-link(href="/docs/5.x/docs/schematypes.html", class=outputUrl === '/docs/schematypes.html' ? 'selected' : '') SchemaTypes
               li.pure-menu-item.sub-item
-                a.pure-menu-link(href="/docs/5.x/connections.html", class=outputUrl === '/docs/connections.html' ? 'selected' : '') Connections
+                a.pure-menu-link(href="/docs/5.x/docs/connections.html", class=outputUrl === '/docs/connections.html' ? 'selected' : '') Connections
               - if (['/docs/connections', '/docs/tutorials/ssl'].some(path => outputUrl.startsWith(path)))
                 li.pure-menu-item.tertiary-item
                   a.pure-menu-link(href="/docs/5.x/tutorials/ssl.html", class=outputUrl === '/docs/tutorials/ssl.html' ? 'selected' : '') SSL Connections

From b34d1d5313ff3380d3cfc5df26d2785a63e86ed0 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Sep 2021 16:13:39 -0400
Subject: [PATCH 2313/2348] fix(index.d.ts): simplify UpdateQuery to avoid
 "excessively deep and possibly infinite" errors with `extends Document` and
 `any`

Fix #10617
---
 index.d.ts | 56 +++++++++++++++++++++++++++---------------------------
 1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 103c8c12a2e..6058939863a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2536,40 +2536,29 @@ declare module 'mongoose' {
 
   type NumericTypes = number | mongodb.Decimal128 | mongodb.Double | mongodb.Int32 | mongodb.Long;
 
-  type KeysOfAType<TSchema, Type> = {
-    [key in keyof TSchema]: NonNullable<TSchema[key]> extends Type ? key : never;
-  }[keyof TSchema];
-
-  type PullOperator<TSchema> = {
-    [key in KeysOfAType<TSchema, ReadonlyArray<any>>]?:
-        | Partial<Unpacked<TSchema[key]>>
-        | mongodb.ObjectQuerySelector<Unpacked<TSchema[key]>>
-        // Doesn't look like TypeScript has good support for creating an
-        // object containing dotted keys:
-        // https://stackoverflow.com/questions/58434389/typescript-deep-keyof-of-a-nested-object
-        | mongodb.QuerySelector<any>
-        | any;
-  } | any; // Because TS doesn't have good support for creating an object with dotted keys, including `.$.` re: #10075
+  type OnlyFieldsOfType<TSchema, FieldType = any, AssignableType = FieldType> = {
+    [key in keyof TSchema]?: [Extract<TSchema[key], FieldType>] extends [never] ? never : AssignableType;
+  };
 
   /** @see https://docs.mongodb.com/manual/reference/operator/update */
   type _UpdateQuery<TSchema> = {
     /** @see https://docs.mongodb.com/manual/reference/operator/update-field/ */
-    $currentDate?: mongodb.OnlyFieldsOfType<TSchema, NativeDate | mongodb.Timestamp, true | { $type: 'date' | 'timestamp' }> | any;
-    $inc?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined> | any;
-    $min?: mongodb.MatchKeysAndValues<TSchema>;
-    $max?: mongodb.MatchKeysAndValues<TSchema>;
-    $mul?: mongodb.OnlyFieldsOfType<TSchema, NumericTypes | undefined> | any;
+    $currentDate?: OnlyFieldsOfType<TSchema, NativeDate, true | { $type: 'date' | 'timestamp' }> & AnyObject;
+    $inc?: OnlyFieldsOfType<TSchema, NumericTypes | undefined> & AnyObject;
+    $min?: OnlyFieldsOfType<TSchema, any, any> & AnyObject;
+    $max?: OnlyFieldsOfType<TSchema, any, any> & AnyObject;
+    $mul?: OnlyFieldsOfType<TSchema, NumericTypes | undefined> & AnyObject;
     $rename?: { [key: string]: string };
-    $set?: mongodb.MatchKeysAndValues<TSchema>;
-    $setOnInsert?: mongodb.MatchKeysAndValues<TSchema>;
-    $unset?: mongodb.OnlyFieldsOfType<TSchema, any, any> | any;
+    $set?: OnlyFieldsOfType<TSchema, any, any> & AnyObject;
+    $setOnInsert?: OnlyFieldsOfType<TSchema, any, any> & AnyObject;
+    $unset?: OnlyFieldsOfType<TSchema, any, any> & AnyObject;
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-array/ */
-    $addToSet?: mongodb.SetFields<TSchema> | any;
-    $pop?: mongodb.OnlyFieldsOfType<TSchema, ReadonlyArray<any>, 1 | -1> | any;
-    $pull?: PullOperator<TSchema>;
-    $push?: mongodb.PushOperator<TSchema> | any;
-    $pullAll?: mongodb.PullAllOperator<TSchema> | any;
+    $addToSet?: OnlyFieldsOfType<TSchema, any[], any> & AnyObject;
+    $pop?: OnlyFieldsOfType<TSchema, ReadonlyArray<any>, 1 | -1> & AnyObject;
+    $pull?: OnlyFieldsOfType<TSchema, ReadonlyArray<any>, any> & AnyObject;
+    $push?: OnlyFieldsOfType<TSchema, ReadonlyArray<any>, any> & AnyObject;
+    $pullAll?: OnlyFieldsOfType<TSchema, ReadonlyArray<any>, any> & AnyObject;
 
     /** @see https://docs.mongodb.com/manual/reference/operator/update-bitwise/ */
     $bit?: {
@@ -2585,7 +2574,18 @@ declare module 'mongoose' {
     { $replaceRoot: any } |
     { $replaceWith: any };
 
-  export type UpdateQuery<T> = (_UpdateQuery<DocumentDefinition<T>> & mongodb.MatchKeysAndValues<DocumentDefinition<T>>);
+  type __UpdateDefProperty<T> =
+    0 extends (1 & T) ? T : // any
+    T extends unknown[] ? LeanArray<T> : // Array
+    T extends Document ? LeanDocument<T> : // Subdocument
+    [Extract<T, mongodb.ObjectId>] extends [never] ? T :
+    T | string;
+  type __UpdateQueryDef<T> = {
+    [K in keyof T]: __UpdateDefProperty<T[K]>;
+  };
+  type _UpdateQueryDef<T> = __UpdateQueryDef<T>;
+
+  export type UpdateQuery<T> = (_UpdateQuery<_UpdateQueryDef<T>> & mongodb.MatchKeysAndValues<_UpdateQueryDef<LeanDocument<T>>>);
 
   type _AllowStringsForIds<T> = {
     [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never]

From 3f7dfc5ab7f227ca6eca3c9e517be20058c902e1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Sep 2021 17:54:10 -0400
Subject: [PATCH 2314/2348] fix(document): make `depopulate()` handle populated
 paths underneath document arrays

Fix #10592
---
 lib/document.js       |  6 ++++--
 test/document.test.js | 44 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index c081a17335d..003156e3f7a 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1368,6 +1368,8 @@ Document.prototype.$set = function $set(path, val, type, options) {
         this.unmarkModified(path);
       }
     }
+  } else {
+    console.log('No shouldSet', path)
   }
 
   if (schema.$isSingleNested && (this.isDirectModified(path) || val == null)) {
@@ -4203,7 +4205,7 @@ Document.prototype.depopulate = function(path) {
         continue;
       }
       delete populated[key];
-      this.$set(key, populatedIds);
+      utils.setValue(key, populatedIds, this._doc);
     }
     return this;
   }
@@ -4216,7 +4218,7 @@ Document.prototype.depopulate = function(path) {
       delete this.$$populatedVirtuals[singlePath];
       delete this._doc[singlePath];
     } else if (populatedIds) {
-      this.$set(singlePath, populatedIds);
+      utils.setValue(singlePath, populatedIds, this._doc);
     }
   }
   return this;
diff --git a/test/document.test.js b/test/document.test.js
index 1026e6abd07..e8b66176a1a 100644
--- a/test/document.test.js
+++ b/test/document.test.js
@@ -10484,4 +10484,48 @@ describe('document', function() {
 
     assert.ok(!doc.nested.otherProp);
   });
+
+  it('depopulate all should depopulate nested array population (gh-10592)', function() {
+
+    const Person = db.model('Person', {
+      name: String
+    });
+
+    const Band = db.model('Band', {
+      name: String,
+      members: [{ type: Schema.Types.ObjectId, ref: 'Person' }],
+      lead: { type: Schema.Types.ObjectId, ref: 'Person' },
+      embeddedMembers: [{
+        active: Boolean,
+        member: {
+          type: Schema.Types.ObjectId, ref: 'Person'
+        }
+      }]
+    });
+
+    return co(function*() {
+      const people = [{ name: 'Axl Rose' }, { name: 'Slash' }];
+
+      const docs = yield Person.create(people);
+      let band = {
+        name: 'Guns N\' Roses',
+        members: [docs[0]._id, docs[1]],
+        lead: docs[0]._id,
+        embeddedMembers: [{ active: true, member: docs[0]._id }, { active: false, member: docs[1]._id }]
+      };
+      band = yield Band.create(band);
+      yield band.populate('members lead').populate('embeddedMembers.member').execPopulate();
+      assert.ok(band.populated('members'));
+      assert.ok(band.populated('lead'));
+      assert.ok(band.populated('embeddedMembers.member'));
+      assert.equal(band.members[0].name, 'Axl Rose');
+      assert.equal(band.embeddedMembers[0].member.name, 'Axl Rose');
+      band.depopulate();
+
+      assert.ok(!band.populated('members'));
+      assert.ok(!band.populated('lead'));
+      assert.ok(!band.populated('embeddedMembers.member'));
+      assert.ok(!band.embeddedMembers[0].member.name);
+    });
+  });
 });

From 1dc9b455a158d8c2e321eb420ad9971fee560744 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 2 Sep 2021 18:00:13 -0400
Subject: [PATCH 2315/2348] style: fix lint

---
 lib/document.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/document.js b/lib/document.js
index 003156e3f7a..d24d1fff2e2 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1369,7 +1369,7 @@ Document.prototype.$set = function $set(path, val, type, options) {
       }
     }
   } else {
-    console.log('No shouldSet', path)
+    console.log('No shouldSet', path);
   }
 
   if (schema.$isSingleNested && (this.isDirectModified(path) || val == null)) {

From 1f28237bf4248ead608765833a0e909125319d02 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Sep 2021 16:26:33 -0400
Subject: [PATCH 2316/2348] fix(populate): avoid setting empty array on lean
 document when populate result is undefined

Fix #10599
---
 lib/helpers/populate/assignVals.js        |  3 ++
 lib/helpers/populate/lookupLocalFields.js |  3 ++
 test/model.populate.test.js               | 37 +++++++++++++++++++++++
 3 files changed, 43 insertions(+)

diff --git a/lib/helpers/populate/assignVals.js b/lib/helpers/populate/assignVals.js
index 33c618dc37c..81ccf61bc88 100644
--- a/lib/helpers/populate/assignVals.js
+++ b/lib/helpers/populate/assignVals.js
@@ -43,6 +43,9 @@ module.exports = function assignVals(o) {
     if (val instanceof SkipPopulateValue) {
       return val.val;
     }
+    if (val === void 0) {
+      return val;
+    }
 
     const _allIds = o.allIds[i];
 
diff --git a/lib/helpers/populate/lookupLocalFields.js b/lib/helpers/populate/lookupLocalFields.js
index 7fcfae561c6..ea641bf8453 100644
--- a/lib/helpers/populate/lookupLocalFields.js
+++ b/lib/helpers/populate/lookupLocalFields.js
@@ -13,6 +13,9 @@ module.exports = function lookupLocalFields(cur, path, val) {
     if (typeof cur !== 'object') {
       return void 0;
     }
+    if (val === void 0) {
+      return void 0;
+    }
     cur[path] = val;
     return val;
   }
diff --git a/test/model.populate.test.js b/test/model.populate.test.js
index 6bedbc3e623..e1621e6007b 100644
--- a/test/model.populate.test.js
+++ b/test/model.populate.test.js
@@ -10565,4 +10565,41 @@ describe('model: populate:', function() {
       assert.equal(populatedBooks[0].author.name, 'Author1');
     });
   });
+
+  it('avoids setting empty array on lean document when populate result is undefined (gh-10599)', function() {
+    return co(function*() {
+      const ImageSchema = Schema({ imageName: String }, { _id: false });
+      const TextSchema = Schema({
+        textName: String,
+        attached: [{ type: 'ObjectId', ref: 'Test2' }]
+      }, { _id: false });
+
+      const ItemSchema = Schema({ objectType: String }, {
+        discriminatorKey: 'objectType',
+        _id: false
+      });
+
+      const ExampleSchema = Schema({ test: String, list: [ItemSchema] });
+
+      ExampleSchema.path('list').discriminator('Image', ImageSchema);
+      ExampleSchema.path('list').discriminator('Text', TextSchema);
+      const Example = db.model('Test', ExampleSchema);
+      const Another = db.model('Test2', Schema({ test: 'String' }));
+
+      yield Another.create({ _id: '61254490ea89de0004c8f2a0', test: 'test' });
+
+      const example = yield Example.create({
+        test: 'example',
+        list: [
+          { imageName: 'an image', objectType: 'Image' },
+          { textName: 'this is a text', attached: ['61254490ea89de0004c8f2a0'], objectType: 'Text' }
+        ]
+      });
+      const query = Example.findById(example._id).populate('list.attached').lean();
+
+      const result = yield query.exec();
+      assert.strictEqual(result.list[0].attached, void 0);
+      assert.equal(result.list[1].attached[0].test, 'test');
+    });
+  });
 });

From fc5fc7e0081bd58774e18c4ca53da59c2ff412b5 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 3 Sep 2021 17:25:20 -0400
Subject: [PATCH 2317/2348] fix: peg @types/bson version to 1.x || 4.0.x to
 avoid stubbed 4.2.x release

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 26c2ed6bb77..c572bc7898d 100644
--- a/package.json
+++ b/package.json
@@ -19,6 +19,7 @@
   ],
   "license": "MIT",
   "dependencies": {
+    "@types/bson": "1.x || 4.0.x",
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",

From 264554fc322132e94c2c0d358d3bf38082776ac8 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Sep 2021 12:39:26 -0400
Subject: [PATCH 2318/2348] fix: upgrade to mpath v0.8.4 re: security issue

Note that the security issue in earlier versions of mpath does **not** affect Mongoose

Fix #10683
---
 lib/document.js | 2 --
 package.json    | 2 +-
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/lib/document.js b/lib/document.js
index d24d1fff2e2..7add115faf5 100644
--- a/lib/document.js
+++ b/lib/document.js
@@ -1368,8 +1368,6 @@ Document.prototype.$set = function $set(path, val, type, options) {
         this.unmarkModified(path);
       }
     }
-  } else {
-    console.log('No shouldSet', path);
   }
 
   if (schema.$isSingleNested && (this.isDirectModified(path) || val == null)) {
diff --git a/package.json b/package.json
index c572bc7898d..c353faf7a9c 100644
--- a/package.json
+++ b/package.json
@@ -25,7 +25,7 @@
     "kareem": "2.3.2",
     "mongodb": "3.6.11",
     "mongoose-legacy-pluralize": "1.0.2",
-    "mpath": "0.8.3",
+    "mpath": "0.8.4",
     "mquery": "3.2.5",
     "ms": "2.1.2",
     "optional-require": "1.0.x",

From 07946be9d79ec345d8cb3e1e650bf30214604342 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 6 Sep 2021 12:51:20 -0400
Subject: [PATCH 2319/2348] chore: release v5.13.9

---
 History.md   | 9 +++++++++
 package.json | 4 ++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/History.md b/History.md
index 9b79c71b4b7..5015630a606 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,12 @@
+5.13.9 / 2021-09-06
+===================
+ * fix(populate): avoid setting empty array on lean document when populate result is undefined #10599
+ * fix(document): make depopulate() handle populated paths underneath document arrays #10592
+ * fix: peg @types/bson version to 1.x || 4.0.x to avoid stubbed 4.2.x release #10678
+ * fix(index.d.ts): simplify UpdateQuery to avoid "excessively deep and possibly infinite" errors with `extends Document` and `any` #10647
+ * fix(index.d.ts): allow specifying weights as an IndexOption #10586
+ * fix: upgrade to mpath v0.8.4 re: security issue #10683
+
 5.13.8 / 2021-08-23
 ===================
  * fix(populate): handle populating subdoc array virtual with sort #10552
diff --git a/package.json b/package.json
index c353faf7a9c..a673e663f4b 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.8",
+  "version": "5.13.9",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",
@@ -79,7 +79,7 @@
     "build-browser": "node build-browser.js",
     "prepublishOnly": "npm run build-browser",
     "release": "git pull && git push origin master --tags && npm publish",
-    "release-legacy": "git pull origin 4.x && git push origin 4.x --tags && npm publish --tag legacy",
+    "release-legacy": "git pull origin 5.x && git push origin 5.x --tags && npm publish --tag legacy",
     "test": "mocha --exit ./test/*.test.js ./test/typescript/main.test.js",
     "tdd": "mocha ./test/*.test.js ./test/typescript/main.test.js --watch --recursive --watch-files ./**/*.js",
     "test-cov": "nyc --reporter=html --reporter=text npm test"

From 1f9e48182289394efa174f0e5563ce7fa989e16f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Oct 2021 13:35:01 -0400
Subject: [PATCH 2320/2348] fix(index.d.ts): allow `AnyObject` as param to
 `findOneAndReplace()`

Fix #10714
---
 index.d.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 6058939863a..5b885c19863 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1004,8 +1004,8 @@ declare module 'mongoose' {
     findOneAndRemove(filter?: FilterQuery<T>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndReplace` query: atomically finds the given document and replaces it with `replacement`. */
-    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T>, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
-    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T>, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndReplace(filter: FilterQuery<T>, replacement: DocumentDefinition<T> | AnyObject, options: QueryOptions & { upsert: true } & ReturnsNewDoc, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods>, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
+    findOneAndReplace(filter?: FilterQuery<T>, replacement?: DocumentDefinition<T> | AnyObject, options?: QueryOptions | null, callback?: (err: CallbackError, doc: EnforceDocument<T, TMethods> | null, res: any) => void): QueryWithHelpers<EnforceDocument<T, TMethods> | null, EnforceDocument<T, TMethods>, TQueryHelpers, T>;
 
     /** Creates a `findOneAndUpdate` query: atomically find the first document that matches `filter` and apply `update`. */
     findOneAndUpdate(filter: FilterQuery<T>, update: UpdateQuery<T> | UpdateWithAggregationPipeline, options: QueryOptions & { rawResult: true }, callback?: (err: CallbackError, doc: mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, res: any) => void): QueryWithHelpers<mongodb.FindAndModifyWriteOpResultObject<EnforceDocument<T, TMethods>>, EnforceDocument<T, TMethods>, TQueryHelpers, T>;

From 1a15331cbaedd99a9a0e562848731234b1f6f54b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Oct 2021 14:19:02 -0400
Subject: [PATCH 2321/2348] fix(index.d.ts): allow using type:
 SchemaDefinitionProperty in schema definitions

Re: #10605
Fix #10674
---
 index.d.ts                      |  4 +++-
 test/typescript/subdocuments.ts | 29 ++++++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 5b885c19863..3547e556601 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1589,13 +1589,15 @@ declare module 'mongoose' {
     currentTime?: () => (NativeDate | number);
   }
 
+  type AnyArray<T> = T[] | ReadonlyArray<T>;
+
   type Unpacked<T> = T extends (infer U)[] ? U : T;
 
   export class SchemaTypeOptions<T> {
     type?:
       T extends string | number | boolean | NativeDate | Function ? SchemaDefinitionWithBuiltInClass<T> :
       T extends Schema<any, any> ? T :
-      T extends object[] ? (Schema<Unpacked<T>>[] | ReadonlyArray<Schema<Unpacked<T>>> | Schema<Document & Unpacked<T>>[] | ReadonlyArray<Schema<Document & Unpacked<T>>>) :
+      T extends object[] ? (AnyArray<Schema<Unpacked<T>>> | AnyArray<Schema<Document & Unpacked<T>>> | AnyArray<SchemaDefinition<Unpacked<T>>>) :
       T extends string[] ? (SchemaDefinitionWithBuiltInClass<string>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<string>>) :
       T extends number[] ? (SchemaDefinitionWithBuiltInClass<number>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<number>>) :
       T extends boolean[] ? (SchemaDefinitionWithBuiltInClass<boolean>[] | ReadonlyArray<SchemaDefinitionWithBuiltInClass<boolean>>) :
diff --git a/test/typescript/subdocuments.ts b/test/typescript/subdocuments.ts
index a1b71f4e0aa..ed0db7eef10 100644
--- a/test/typescript/subdocuments.ts
+++ b/test/typescript/subdocuments.ts
@@ -1,4 +1,4 @@
-import { Schema, model, Document } from 'mongoose';
+import { Schema, model, Model, Document } from 'mongoose';
 
 const childSchema: Schema = new Schema({ name: String });
 
@@ -26,3 +26,30 @@ const doc: ITest = new Test({});
 
 doc.child1 = { name: 'test1' };
 doc.child2 = { name: 'test2' };
+
+function gh10674() {
+  type Foo = {
+    bar: string
+    schedule: {
+      date: string;
+      hours: number;
+    }[];
+  };
+
+  type FooModel = Model<Foo>;
+
+  const FooSchema = new Schema<Foo, FooModel, Foo>(
+    {
+      bar: { type: String },
+      schedule: {
+        type: [
+          {
+            date: { type: String, required: true },
+            hours: { type: Number, required: true }
+          }
+        ],
+        required: true
+      }
+    }
+  );
+}

From d99f42cc34f25ed7e5b723d5cba9bb2caaaa62e2 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 5 Oct 2021 14:33:19 -0400
Subject: [PATCH 2322/2348] chore: release 5.13.10

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 5015630a606..040e3abda9b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.13.10 / 2021-10-05
+====================
+ * fix(index.d.ts): allow using type: SchemaDefinitionProperty in schema definitions #10674
+ * fix(index.d.ts): allow AnyObject as param to findOneAndReplace() #10714
+
 5.13.9 / 2021-09-06
 ===================
  * fix(populate): avoid setting empty array on lean document when populate result is undefined #10599
diff --git a/package.json b/package.json
index a673e663f4b..19333825658 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.9",
+  "version": "5.13.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 30efc3999373085870e7a53b755969b72c40a647 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 11 Oct 2021 15:06:29 -0400
Subject: [PATCH 2323/2348] fix(connection): call `setMaxListeners(0)` on
 MongoClient to avoid event emitter memory leak warnings with `useDb()`

Fix #10762
---
 lib/connection.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/connection.js b/lib/connection.js
index aeb923ef307..89fdc9077d7 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -832,6 +832,7 @@ Connection.prototype.openUri = function(uri, options, callback) {
   const promise = new Promise((resolve, reject) => {
     const client = new mongodb.MongoClient(uri, options);
     _this.client = client;
+    client.setMaxListeners(0);
     client.connect((error) => {
       if (error) {
         return reject(error);

From 1192162c790d0474a4c31b6030a11a3de30efe01 Mon Sep 17 00:00:00 2001
From: Winston Ralph <winston.ralph@mercer.com>
Date: Tue, 12 Oct 2021 12:44:13 +0100
Subject: [PATCH 2324/2348] fix(security): updated mongodb dependency due to
 vulnerabilities

---
 package.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 19333825658..dcbf91a557f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.10",
+  "version": "5.13.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",
@@ -23,7 +23,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.6.11",
+    "mongodb": "3.7.2",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.4",
     "mquery": "3.2.5",

From 8dd66ca7a7ff8fabd837dd3efca00f6f93c4d7f1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 12 Oct 2021 11:17:55 -0400
Subject: [PATCH 2325/2348] chore: undo mistaken version bump

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index dcbf91a557f..4d26b65605a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.11",
+  "version": "5.13.10",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 4b8e0d125aa031ab8ebe12fafde76443c732190d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 12 Oct 2021 17:10:12 -0400
Subject: [PATCH 2326/2348] chore: release 5.13.11

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 040e3abda9b..fb611eeb9ab 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.13.11 / 2021-10-12
+====================
+ * fix: upgrade mongodb -> 3.7.2 #10871 [winstonralph](https://github.com/winstonralph)
+ * fix(connection): call setMaxListeners(0) on MongoClient to avoid event emitter memory leak warnings with `useDb()` #10732
+
 5.13.10 / 2021-10-05
 ====================
  * fix(index.d.ts): allow using type: SchemaDefinitionProperty in schema definitions #10674
diff --git a/package.json b/package.json
index 4d26b65605a..dcbf91a557f 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.10",
+  "version": "5.13.11",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From f1376f35296403e8e72f1f1d79c2fdf1d3feac67 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Thu, 14 Oct 2021 17:24:17 -0400
Subject: [PATCH 2327/2348] fix(index.d.ts): backport streamlining of
 FilterQuery and DocumentDefinition to avoid "excessively deep and possibly
 infinite" TS errors

Fix #10617
---
 index.d.ts | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/index.d.ts b/index.d.ts
index 3547e556601..27b8f348745 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2524,15 +2524,9 @@ declare module 'mongoose' {
   }
 
   type _FilterQuery<T> = {
-    [P in keyof T]?: P extends '_id'
-    ? [Extract<T[P], mongodb.ObjectId>] extends [never]
-    ? mongodb.Condition<T[P]>
-    : mongodb.Condition<T[P] | string | { _id: mongodb.ObjectId }>
-    : [Extract<T[P], mongodb.ObjectId>] extends [never]
-    ? mongodb.Condition<T[P]>
-    : mongodb.Condition<T[P] | string>;
+    [P in keyof T]?: mongodb.Condition<[Extract<T[P], mongodb.ObjectId>] extends [never] ? T[P] : T[P] | string>;
   } &
-    mongodb.RootQuerySelector<DocumentDefinition<T>>;
+    mongodb.RootQuerySelector<T>;
 
   export type FilterQuery<T> = _FilterQuery<T>;
 
@@ -2589,14 +2583,14 @@ declare module 'mongoose' {
 
   export type UpdateQuery<T> = (_UpdateQuery<_UpdateQueryDef<T>> & mongodb.MatchKeysAndValues<_UpdateQueryDef<LeanDocument<T>>>);
 
-  type _AllowStringsForIds<T> = {
-    [K in keyof T]: [Extract<T[K], mongodb.ObjectId>] extends [never]
+  export type DocumentDefinition<T> = {
+    [K in keyof Omit<T, Exclude<keyof Document, '_id' | 'id' | '__v'>>]:
+      [Extract<T[K], mongodb.ObjectId>] extends [never]
       ? T[K] extends TreatAsPrimitives
         ? T[K]
-        : _AllowStringsForIds<T[K]>
+        : LeanDocumentElement<T[K]>
       : T[K] | string;
     };
-  export type DocumentDefinition<T> = _AllowStringsForIds<LeanDocument<T>>;
 
   type actualPrimitives = string | boolean | number | bigint | symbol | null | undefined;
   type TreatAsPrimitives = actualPrimitives |

From 46165d6c720967c15586f2b42df51663db5e677a Mon Sep 17 00:00:00 2001
From: Ivan Majeru <ivanmajeru@gmail.com>
Date: Mon, 18 Oct 2021 12:30:09 +0300
Subject: [PATCH 2328/2348] [gh-10875] Use stream destroy method on close to
 prevent emit 'close' event twice

---
 lib/cursor/AggregationCursor.js |  9 ++++++-
 lib/cursor/QueryCursor.js       |  9 ++++++-
 test/query.cursor.test.js       | 42 +++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 2 deletions(-)

diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 6131bab5d85..4a84429a031 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -90,7 +90,14 @@ AggregationCursor.prototype._read = function() {
           // on node >= 14 streams close automatically (gh-8834)
           const isNotClosedAutomatically = !_this.destroyed;
           if (isNotClosedAutomatically) {
-            _this.emit('close');
+            // call destroy method if exists to prevent emit twice 'close' by autoDestroy (gh-10876)
+            // @see https://nodejs.org/api/stream.html#stream_readable_destroy_error
+            // the 'close' is emited on destroy started with version 10
+            if (_this.destroy && parseInt(process.versions.node.split('.')[0]) > 9) {
+              _this.destroy();
+            } else {
+              _this.emit('close');
+            }
           }
         }, 0);
       });
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index 49e3a4d9d10..e5b7f032400 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -99,7 +99,14 @@ QueryCursor.prototype._read = function() {
           // on node >= 14 streams close automatically (gh-8834)
           const isNotClosedAutomatically = !_this.destroyed;
           if (isNotClosedAutomatically) {
-            _this.emit('close');
+            // call destroy method if exists to prevent emit twice 'close' by autoDestroy (gh-10876)
+            // @see https://nodejs.org/api/stream.html#stream_readable_destroy_error
+            // the close is emited on destroy started with version 10
+            if (_this.destroy && parseInt(process.versions.node.split('.')[0]) > 9) {
+              _this.destroy();
+            } else {
+              _this.emit('close');
+            }
           }
         }, 0);
       });
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index b2ce61f9569..debacbbb1b1 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -644,6 +644,48 @@ describe('QueryCursor', function() {
     }, 20);
   });
 
+  it('closing query cursor emits `close` event only once with stream pause/resume (gh-10876)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    User.create({ name: 'First' }, { name: 'Second' })
+      .then(() => {
+        const cursor = User.find().cursor();
+        cursor.on('data', () => {
+          cursor.pause();
+          setTimeout(() => cursor.resume(), 50);
+        });
+
+        let closeEventTriggeredCount = 0;
+        cursor.on('close', () => closeEventTriggeredCount++);
+        setTimeout(() => {
+          assert.equal(closeEventTriggeredCount, 1);
+          done();
+        }, 200);
+      });
+  });
+
+  it('closing aggregation cursor emits `close` event only once with stream pause/resume (gh-10876)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    User.create({ name: 'First' }, { name: 'Second' })
+      .then(() => {
+        const cursor = User.aggregate([{ $match: {} }]).cursor().exec();
+        cursor.on('data', () => {
+          cursor.pause();
+          setTimeout(() => cursor.resume(), 50);
+        });
+
+        let closeEventTriggeredCount = 0;
+        cursor.on('close', () => closeEventTriggeredCount++);
+
+
+        setTimeout(() => {
+          assert.equal(closeEventTriggeredCount, 1);
+          done();
+        }, 200);
+      });
+  });
+
   it('passes document index as the second argument for query cursor (gh-8972)', function() {
     return co(function *() {
       const User = db.model('User', Schema({ order: Number }));

From 7b4e4e7a93e87ab54cf9931a9a50cfcf8a7cb10a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Oct 2021 13:46:01 -0400
Subject: [PATCH 2329/2348] test: hopefully fix Node v4 tests on 5.x branch

---
 package.json              |  1 -
 test/model.update.test.js | 20 --------------------
 2 files changed, 21 deletions(-)

diff --git a/package.json b/package.json
index dcbf91a557f..2a251415bf0 100644
--- a/package.json
+++ b/package.json
@@ -58,7 +58,6 @@
     "mkdirp": "0.5.5",
     "mocha": "5.x",
     "moment": "2.x",
-    "mongoose-long": "0.2.1",
     "node-static": "0.7.11",
     "object-sizeof": "1.3.0",
     "pug": "2.0.3",
diff --git a/test/model.update.test.js b/test/model.update.test.js
index b0ba39368d9..39f6ca81a6e 100644
--- a/test/model.update.test.js
+++ b/test/model.update.test.js
@@ -2123,26 +2123,6 @@ describe('model: update:', function() {
       });
     });
 
-    it('update handles casting with mongoose-long (gh-4283)', function(done) {
-      require('mongoose-long')(mongoose);
-
-      const Model = db.model('Test', {
-        number: { type: mongoose.Types.Long }
-      });
-
-      Model.create({ number: mongoose.mongo.Long.fromString('0') }, function(error) {
-        assert.ifError(error);
-        Model.update({}, { $inc: { number: mongoose.mongo.Long.fromString('2147483648') } }, function(error) {
-          assert.ifError(error);
-          Model.findOne({ number: { $type: 18 } }, function(error, doc) {
-            assert.ifError(error);
-            assert.ok(doc);
-            done();
-          });
-        });
-      });
-    });
-
     it('single nested with runValidators (gh-4420)', function(done) {
       const FileSchema = new Schema({
         name: String

From ec4f07ee78b31befc30a9d101b143013f32dc02e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 19 Oct 2021 13:54:41 -0400
Subject: [PATCH 2330/2348] chore: release 5.13.12

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index fb611eeb9ab..565c342492f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.13.12 / 2021-10-19
+====================
+ * fix(cursor): use stream destroy method on close to prevent emitting duplicate 'close' #10897 [iovanom](https://github.com/iovanom)
+ * fix(index.d.ts): backport streamlining of FilterQuery and DocumentDefinition to avoid "excessively deep and possibly infinite" TS errors #10617
+
 5.13.11 / 2021-10-12
 ====================
  * fix: upgrade mongodb -> 3.7.2 #10871 [winstonralph](https://github.com/winstonralph)
diff --git a/package.json b/package.json
index 2a251415bf0..4eef0a37e19 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.11",
+  "version": "5.13.12",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From b7ebeecbf670ac6efd9b01f8ae1ff8f70c4fbd1d Mon Sep 17 00:00:00 2001
From: Lorand Horvath <72015221+lorand-horvath@users.noreply.github.com>
Date: Thu, 21 Oct 2021 13:26:02 +0300
Subject: [PATCH 2331/2348] Update mongodb driver to 3.7.3

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 4eef0a37e19..985db168020 100644
--- a/package.json
+++ b/package.json
@@ -23,7 +23,7 @@
     "@types/mongodb": "^3.5.27",
     "bson": "^1.1.4",
     "kareem": "2.3.2",
-    "mongodb": "3.7.2",
+    "mongodb": "3.7.3",
     "mongoose-legacy-pluralize": "1.0.2",
     "mpath": "0.8.4",
     "mquery": "3.2.5",

From 5468642ed2f8ebe5032e91a362f6ab4dafee9139 Mon Sep 17 00:00:00 2001
From: Ivan Majeru <ivanmajeru@gmail.com>
Date: Fri, 22 Oct 2021 18:23:43 +0300
Subject: [PATCH 2332/2348] [gh-10902 v5] Emit end event in before close

---
 lib/cursor/AggregationCursor.js | 27 +++++------
 lib/cursor/QueryCursor.js       | 27 +++++------
 test/query.cursor.test.js       | 82 +++++++++++++++++++++++++++++++++
 3 files changed, 106 insertions(+), 30 deletions(-)

diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 4a84429a031..7b3ff46f463 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -36,7 +36,14 @@ const util = require('util');
  */
 
 function AggregationCursor(agg) {
-  Readable.call(this, { objectMode: true });
+  const streamOpts = { objectMode: true };
+  // for node < 12 we will emit 'close' event after 'end'
+  if (parseInt(process.versions.node.split('.')[0]) >= 12) {
+    // set autoDestroy=true because on node 12 it's by default false
+    // gh-10902 need autoDestroy to destroy correctly and emit 'close' event for node >= 12
+    streamOpts.autoDestroy = true;
+  }
+  Readable.call(this, streamOpts);
 
   this.cursor = null;
   this.agg = agg;
@@ -86,20 +93,10 @@ AggregationCursor.prototype._read = function() {
         if (error) {
           return _this.emit('error', error);
         }
-        setTimeout(function() {
-          // on node >= 14 streams close automatically (gh-8834)
-          const isNotClosedAutomatically = !_this.destroyed;
-          if (isNotClosedAutomatically) {
-            // call destroy method if exists to prevent emit twice 'close' by autoDestroy (gh-10876)
-            // @see https://nodejs.org/api/stream.html#stream_readable_destroy_error
-            // the 'close' is emited on destroy started with version 10
-            if (_this.destroy && parseInt(process.versions.node.split('.')[0]) > 9) {
-              _this.destroy();
-            } else {
-              _this.emit('close');
-            }
-          }
-        }, 0);
+        // for node >= 12 the autoDestroy will emit the 'close' event
+        if (parseInt(process.versions.node.split('.')[0]) < 12) {
+          _this.on('end', () => _this.emit('close'));
+        }
       });
       return;
     }
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index e5b7f032400..d6e295238ee 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -34,7 +34,14 @@ const util = require('util');
  */
 
 function QueryCursor(query, options) {
-  Readable.call(this, { objectMode: true });
+  const streamOpts = { objectMode: true };
+  // for node < 12 we will emit 'close' event after 'end'
+  if (parseInt(process.versions.node.split('.')[0]) >= 12) {
+    // set autoDestroy=true because on node 12 it's by default false
+    // gh-10902 need autoDestroy to destroy correctly and emit 'close' event for node >= 12
+    streamOpts.autoDestroy = true;
+  }
+  Readable.call(this, streamOpts);
 
   this.cursor = null;
   this.query = query;
@@ -95,20 +102,10 @@ QueryCursor.prototype._read = function() {
         if (error) {
           return _this.emit('error', error);
         }
-        setTimeout(function() {
-          // on node >= 14 streams close automatically (gh-8834)
-          const isNotClosedAutomatically = !_this.destroyed;
-          if (isNotClosedAutomatically) {
-            // call destroy method if exists to prevent emit twice 'close' by autoDestroy (gh-10876)
-            // @see https://nodejs.org/api/stream.html#stream_readable_destroy_error
-            // the close is emited on destroy started with version 10
-            if (_this.destroy && parseInt(process.versions.node.split('.')[0]) > 9) {
-              _this.destroy();
-            } else {
-              _this.emit('close');
-            }
-          }
-        }, 0);
+        // for node >= 12 the autoDestroy will emit the 'close' event
+        if (parseInt(process.versions.node.split('.')[0]) < 12) {
+          _this.on('end', () => _this.emit('close'));
+        }
       });
       return;
     }
diff --git a/test/query.cursor.test.js b/test/query.cursor.test.js
index debacbbb1b1..9ca94eda435 100644
--- a/test/query.cursor.test.js
+++ b/test/query.cursor.test.js
@@ -686,6 +686,88 @@ describe('QueryCursor', function() {
       });
   });
 
+  it('query cursor emit end event (gh-10902)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    User.create({ name: 'First' }, { name: 'Second' })
+      .then(() => {
+        const cursor = User.find({}).cursor();
+        cursor.on('data', () => {
+          cursor.pause();
+          setTimeout(() => cursor.resume(), 50);
+        });
+
+        let endEventTriggeredCount = 0;
+        cursor.on('end', () => endEventTriggeredCount++);
+
+        setTimeout(() => {
+          assert.equal(endEventTriggeredCount, 1);
+          done();
+        }, 200);
+      });
+  });
+
+  it('aggregate cursor emit end event (gh-10902)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    User.create({ name: 'First' }, { name: 'Second' })
+      .then(() => {
+        const cursor = User.aggregate([{ $match: {} }]).cursor().exec();
+        cursor.on('data', () => {
+          cursor.pause();
+          setTimeout(() => cursor.resume(), 50);
+        });
+
+        let endEventTriggeredCount = 0;
+        cursor.on('end', () => endEventTriggeredCount++);
+
+        setTimeout(() => {
+          assert.equal(endEventTriggeredCount, 1);
+          done();
+        }, 200);
+      });
+  });
+
+  it('query cursor emit end event before close event (gh-10902)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    User.create({ name: 'First' }, { name: 'Second' })
+      .then(() => {
+        const cursor = User.find({}).cursor();
+        cursor.on('data', () => {
+          cursor.pause();
+          setTimeout(() => cursor.resume(), 50);
+        });
+
+        let endEventTriggeredCount = 0;
+        cursor.on('end', () => endEventTriggeredCount++);
+        cursor.on('close', () => {
+          assert.equal(endEventTriggeredCount, 1);
+          done();
+        });
+      });
+  });
+
+  it('aggregate cursor emit end event before close event (gh-10902)', function(done) {
+    const User = db.model('User', new Schema({ name: String }));
+
+    User.create({ name: 'First' }, { name: 'Second' })
+      .then(() => {
+        const cursor = User.aggregate([{ $match: {} }]).cursor().exec();
+        cursor.on('data', () => {
+          cursor.pause();
+          setTimeout(() => cursor.resume(), 50);
+        });
+
+        let endEventTriggeredCount = 0;
+        cursor.on('end', () => endEventTriggeredCount++);
+        cursor.on('close', () => {
+          assert.equal(endEventTriggeredCount, 1);
+          done();
+        });
+      });
+  });
+
   it('passes document index as the second argument for query cursor (gh-8972)', function() {
     return co(function *() {
       const User = db.model('User', Schema({ order: Number }));

From 22e9b3b15edfc94169a291019a9d760ff755cda3 Mon Sep 17 00:00:00 2001
From: Ivan Majeru <ivanmajeru@gmail.com>
Date: Fri, 29 Oct 2021 11:17:47 +0300
Subject: [PATCH 2333/2348] [gh-10902 v5] Add node major version to utils

---
 lib/cursor/AggregationCursor.js | 5 +++--
 lib/cursor/QueryCursor.js       | 5 +++--
 lib/utils.js                    | 4 +++-
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/lib/cursor/AggregationCursor.js b/lib/cursor/AggregationCursor.js
index 7b3ff46f463..cec302a9f11 100644
--- a/lib/cursor/AggregationCursor.js
+++ b/lib/cursor/AggregationCursor.js
@@ -10,6 +10,7 @@ const promiseOrCallback = require('../helpers/promiseOrCallback');
 const eachAsync = require('../helpers/cursor/eachAsync');
 const immediate = require('../helpers/immediate');
 const util = require('util');
+const utils = require('../../lib/utils');
 
 /**
  * An AggregationCursor is a concurrency primitive for processing aggregation
@@ -38,7 +39,7 @@ const util = require('util');
 function AggregationCursor(agg) {
   const streamOpts = { objectMode: true };
   // for node < 12 we will emit 'close' event after 'end'
-  if (parseInt(process.versions.node.split('.')[0]) >= 12) {
+  if (utils.nodeMajorVersion >= 12) {
     // set autoDestroy=true because on node 12 it's by default false
     // gh-10902 need autoDestroy to destroy correctly and emit 'close' event for node >= 12
     streamOpts.autoDestroy = true;
@@ -94,7 +95,7 @@ AggregationCursor.prototype._read = function() {
           return _this.emit('error', error);
         }
         // for node >= 12 the autoDestroy will emit the 'close' event
-        if (parseInt(process.versions.node.split('.')[0]) < 12) {
+        if (utils.nodeMajorVersion < 12) {
           _this.on('end', () => _this.emit('close'));
         }
       });
diff --git a/lib/cursor/QueryCursor.js b/lib/cursor/QueryCursor.js
index d6e295238ee..9eec7b074b0 100644
--- a/lib/cursor/QueryCursor.js
+++ b/lib/cursor/QueryCursor.js
@@ -10,6 +10,7 @@ const eachAsync = require('../helpers/cursor/eachAsync');
 const helpers = require('../queryhelpers');
 const immediate = require('../helpers/immediate');
 const util = require('util');
+const utils = require('../../lib/utils');
 
 /**
  * A QueryCursor is a concurrency primitive for processing query results
@@ -36,7 +37,7 @@ const util = require('util');
 function QueryCursor(query, options) {
   const streamOpts = { objectMode: true };
   // for node < 12 we will emit 'close' event after 'end'
-  if (parseInt(process.versions.node.split('.')[0]) >= 12) {
+  if (utils.nodeMajorVersion >= 12) {
     // set autoDestroy=true because on node 12 it's by default false
     // gh-10902 need autoDestroy to destroy correctly and emit 'close' event for node >= 12
     streamOpts.autoDestroy = true;
@@ -103,7 +104,7 @@ QueryCursor.prototype._read = function() {
           return _this.emit('error', error);
         }
         // for node >= 12 the autoDestroy will emit the 'close' event
-        if (parseInt(process.versions.node.split('.')[0]) < 12) {
+        if (utils.nodeMajorVersion < 12) {
           _this.on('end', () => _this.emit('close'));
         }
       });
diff --git a/lib/utils.js b/lib/utils.js
index d6e2dc4e355..e872b1f2cb1 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -934,4 +934,6 @@ exports.errorToPOJO = function errorToPOJO(error) {
     ret[properyName] = error[properyName];
   }
   return ret;
-};
\ No newline at end of file
+};
+
+exports.nodeMajorVersion = parseInt(process.versions.node.split('.')[0]);

From c6fd7f780a626535cddd3454b6f2a621ffb397a5 Mon Sep 17 00:00:00 2001
From: Jason Neal <88398073+jneal-afs@users.noreply.github.com>
Date: Fri, 29 Oct 2021 21:06:06 -0400
Subject: [PATCH 2334/2348] Fix ts types for query set

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index 27b8f348745..fc969e469c3 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2442,7 +2442,7 @@ declare module 'mongoose' {
      * This is useful for query middleware so you can add an update regardless
      * of whether you use `updateOne()`, `updateMany()`, `findOneAndUpdate()`, etc.
      */
-    set(path: string, value: any): this;
+    set(path: string | Record<string, unknown>, value: any): this;
 
     /** Sets query options. Some options only make sense for certain operations. */
     setOptions(options: QueryOptions, overwrite?: boolean): this;

From d205c4d8a3560dd432eace40a0a5acf913726dd2 Mon Sep 17 00:00:00 2001
From: Jason Neal <88398073+jneal-afs@users.noreply.github.com>
Date: Fri, 29 Oct 2021 21:08:58 -0400
Subject: [PATCH 2335/2348] make value optional

---
 index.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/index.d.ts b/index.d.ts
index fc969e469c3..695fe60b3b4 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -2442,7 +2442,7 @@ declare module 'mongoose' {
      * This is useful for query middleware so you can add an update regardless
      * of whether you use `updateOne()`, `updateMany()`, `findOneAndUpdate()`, etc.
      */
-    set(path: string | Record<string, unknown>, value: any): this;
+    set(path: string | Record<string, unknown>, value?: any): this;
 
     /** Sets query options. Some options only make sense for certain operations. */
     setOptions(options: QueryOptions, overwrite?: boolean): this;

From ff5ddb530b1378926b5753f58a566fae00b3c419 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 1 Nov 2021 21:19:27 -0400
Subject: [PATCH 2336/2348] fix: hardcode base 10 for nodeMajorVersion
 parseInt() call

---
 lib/utils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/utils.js b/lib/utils.js
index e872b1f2cb1..1c531f4efd0 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -936,4 +936,4 @@ exports.errorToPOJO = function errorToPOJO(error) {
   return ret;
 };
 
-exports.nodeMajorVersion = parseInt(process.versions.node.split('.')[0]);
+exports.nodeMajorVersion = parseInt(process.versions.node.split('.')[0], 10);

From a7384400a7df87ef258fe596d151f9a82b12b32a Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Tue, 2 Nov 2021 15:10:49 -0400
Subject: [PATCH 2337/2348] chore: release 5.13.13

---
 History.md   | 6 ++++++
 package.json | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 565c342492f..c983b20482b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,9 @@
+5.13.13 / 2021-11-02
+====================
+ * fix: upgrade to mongodb@3.7.3 #10909 [gaurav-sharma-gs](https://github.com/gaurav-sharma-gs)
+ * fix: correctly emit end event in before close #10916 [iovanom](https://github.com/iovanom)
+ * fix(index.d.ts): improve ts types for query set #10942 [jneal-afs](https://github.com/jneal-afs)
+
 5.13.12 / 2021-10-19
 ====================
  * fix(cursor): use stream destroy method on close to prevent emitting duplicate 'close' #10897 [iovanom](https://github.com/iovanom)
diff --git a/package.json b/package.json
index 985db168020..dce37a6600d 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.12",
+  "version": "5.13.13",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 4cfc4d61530446c0d25f231e3b8358776fbe7a6f Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Dec 2021 21:10:20 -0500
Subject: [PATCH 2338/2348] fix(timestamps): avoid setting `createdAt` on
 documents that already exist but dont have createdAt

Fix #11024
---
 lib/helpers/timestamps/setupTimestamps.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/helpers/timestamps/setupTimestamps.js b/lib/helpers/timestamps/setupTimestamps.js
index 904485b0ba8..6eb4c7955e8 100644
--- a/lib/helpers/timestamps/setupTimestamps.js
+++ b/lib/helpers/timestamps/setupTimestamps.js
@@ -51,7 +51,7 @@ module.exports = function setupTimestamps(schema, timestamps) {
       (this.ownerDocument ? this.ownerDocument() : this).constructor.base.now();
     const auto_id = this._id && this._id.auto;
 
-    if (!skipCreatedAt && createdAt && !this.get(createdAt) && this.$__isSelected(createdAt)) {
+    if (!skipCreatedAt && this.isNew && createdAt && !this.get(createdAt) && this.$__isSelected(createdAt)) {
       this.$set(createdAt, auto_id ? this._id.getTimestamp() : defaultTimestamp);
     }
 

From 69c1f6c1429d2be5fdc625d4ba90bd332dc217ca Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 26 Dec 2021 21:30:51 -0500
Subject: [PATCH 2339/2348] docs(models): fix up nModified example for 5.x

Fix #11055
---
 docs/models.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/models.md b/docs/models.md
index 476546f8fd0..257ea18bdce 100644
--- a/docs/models.md
+++ b/docs/models.md
@@ -103,7 +103,7 @@ database without returning them to your application. See the
 
 ```javascript
 Tank.updateOne({ size: 'large' }, { name: 'T-90' }, function(err, res) {
-  // Updated at most one doc, `res.modifiedCount` contains the number
+  // Updated at most one doc, `res.nModified` contains the number
   // of docs that MongoDB updated
 });
 ```

From d2b846fc8f850a82605b74148854a79769f7019b Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 27 Dec 2021 12:54:15 -0500
Subject: [PATCH 2340/2348] chore: release 5.13.14

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index c983b20482b..6891820d86a 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.13.14 / 2021-12-27
+====================
+ * fix(timestamps): avoid setting createdAt on documents that already exist but dont have createdAt #11024
+ * docs(models): fix up nModified example for 5.x #11055
+
 5.13.13 / 2021-11-02
 ====================
  * fix: upgrade to mongodb@3.7.3 #10909 [gaurav-sharma-gs](https://github.com/gaurav-sharma-gs)
diff --git a/package.json b/package.json
index dce37a6600d..8434ae258a1 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.13",
+  "version": "5.13.14",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",

From 05ce5771ab2ceafc51d8c7f27fbe6e52fa23e390 Mon Sep 17 00:00:00 2001
From: "Laisson R. Silveira" <laisson.r.silveira@gmail.com>
Date: Tue, 8 Feb 2022 15:18:30 -0300
Subject: [PATCH 2341/2348] Fix broken link from findandmodify method
 deprecation

---
 docs/deprecations.md | 2 +-
 lib/query.js         | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/deprecations.md b/docs/deprecations.md
index f8a3472bc54..b17953659c0 100644
--- a/docs/deprecations.md
+++ b/docs/deprecations.md
@@ -60,7 +60,7 @@ If you use [`Model.findOneAndUpdate()`](/docs/api.html#model_Model.findOneAndUpd
 by default you'll see one of the below deprecation warnings.
 
 ```
-DeprecationWarning: Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the `useFindAndModify` option set to false are deprecated. See: https://mongoosejs.com/docs/deprecations.html#findandmodify
+DeprecationWarning: Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the `useFindAndModify` option set to false are deprecated. See: https://mongoosejs.com/docs/5.x/docs/deprecations.html#findandmodify
 DeprecationWarning: collection.findAndModify is deprecated. Use findOneAndUpdate, findOneAndReplace or findOneAndDelete instead.
 ```
 
diff --git a/lib/query.js b/lib/query.js
index 4eb5b4a4cde..65817f65fc0 100644
--- a/lib/query.js
+++ b/lib/query.js
@@ -3777,7 +3777,7 @@ const _legacyFindAndModify = util.deprecate(function(filter, update, opts, cb) {
   collection.collection._findAndModify(filter, sort, update, opts, _cb);
 }, 'Mongoose: `findOneAndUpdate()` and `findOneAndDelete()` without the ' +
   '`useFindAndModify` option set to false are deprecated. See: ' +
-  'https://mongoosejs.com/docs/deprecations.html#findandmodify');
+  'https://mongoosejs.com/docs/5.x/docs/deprecations.html#findandmodify');
 
 /*!
  * Override mquery.prototype._mergeUpdate to handle mongoose objects in

From 6a197316564742c0422309e1b5fecfa4faec126e Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 18 Jul 2022 22:21:57 -0400
Subject: [PATCH 2342/2348] fix(schema): disallow setting __proto__ when
 creating schema with dotted properties

Fix #12085
---
 lib/schema.js       |  7 +++++++
 test/schema.test.js | 10 ++++++++++
 2 files changed, 17 insertions(+)

diff --git a/lib/schema.js b/lib/schema.js
index c740902d2fd..895e452a36c 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -478,6 +478,10 @@ Schema.prototype.add = function add(obj, prefix) {
   const keys = Object.keys(obj);
 
   for (const key of keys) {
+    if (utils.specialProperties.has(key)) {
+      continue;
+    }
+
     const fullPath = prefix + key;
 
     if (obj[key] == null) {
@@ -663,6 +667,9 @@ Schema.prototype.path = function(path, obj) {
   let fullPath = '';
 
   for (const sub of subpaths) {
+    if (utils.specialProperties.has(sub)) {
+      throw new Error('Cannot set special property `' + sub + '` on a schema');
+    }
     fullPath = fullPath += (fullPath.length > 0 ? '.' : '') + sub;
     if (!branch[sub]) {
       this.nested[fullPath] = true;
diff --git a/test/schema.test.js b/test/schema.test.js
index f5adc214066..711054abccd 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2682,4 +2682,14 @@ describe('schema', function() {
     assert.equal(TestSchema.path('testprop.$*').instance, 'Number');
     assert.equal(TestSchema.path('testprop.$*').options.ref, 'OtherModel');
   });
+  
+  it('disallows setting special properties with `add()` or constructor (gh-12085)', async function() {
+    const maliciousPayload = '{"__proto__.toString": "Number"}';
+
+    assert.throws(() => {
+      mongoose.Schema(JSON.parse(maliciousPayload));
+    }, /__proto__/);
+
+    assert.ok({}.toString());
+  });
 });

From 5eb11dd5d434ba24ea10d19e5eb2054a276bb22e Mon Sep 17 00:00:00 2001
From: Shubanker Chourasia <shubanker.chourasia@sap.com>
Date: Fri, 19 Aug 2022 13:48:46 +0530
Subject: [PATCH 2343/2348] made function non async

---
 test/schema.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/schema.test.js b/test/schema.test.js
index 711054abccd..d2bff3ce34e 100644
--- a/test/schema.test.js
+++ b/test/schema.test.js
@@ -2682,8 +2682,8 @@ describe('schema', function() {
     assert.equal(TestSchema.path('testprop.$*').instance, 'Number');
     assert.equal(TestSchema.path('testprop.$*').options.ref, 'OtherModel');
   });
-  
-  it('disallows setting special properties with `add()` or constructor (gh-12085)', async function() {
+
+  it('disallows setting special properties with `add()` or constructor (gh-12085)', function() {
     const maliciousPayload = '{"__proto__.toString": "Number"}';
 
     assert.throws(() => {

From 4d813fa01bb9170f4e0a91d0f3f5234bc163d501 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 21 Aug 2022 17:12:24 -0400
Subject: [PATCH 2344/2348] test: fix @types/node version in tests re: #12297

---
 package.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/package.json b/package.json
index 8434ae258a1..856290dcf29 100644
--- a/package.json
+++ b/package.json
@@ -39,6 +39,7 @@
     "@babel/preset-env": "7.10.4",
     "@typescript-eslint/eslint-plugin": "4.10.0",
     "@typescript-eslint/parser": "4.10.0",
+    "@types/node": "16.x",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",

From b9e985c629e05a9a73f23ae42027e6c215c6a9d1 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 21 Aug 2022 17:16:39 -0400
Subject: [PATCH 2345/2348] test: more strict @types/node version

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 856290dcf29..4a70cd5cb62 100644
--- a/package.json
+++ b/package.json
@@ -39,7 +39,7 @@
     "@babel/preset-env": "7.10.4",
     "@typescript-eslint/eslint-plugin": "4.10.0",
     "@typescript-eslint/parser": "4.10.0",
-    "@types/node": "16.x",
+    "@types/node": "16.11.23",
     "acquit": "1.x",
     "acquit-ignore": "0.1.x",
     "acquit-require": "0.1.x",

From dfc4ad750bf91ae5743ed8dce676bf5a96041a6d Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 21 Aug 2022 19:12:33 -0400
Subject: [PATCH 2346/2348] test: try upgrading npm for node v4 tests re:
 #12297

---
 .github/workflows/test.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 9c1b78b454e..7a4eb6af80d 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -18,9 +18,9 @@ jobs:
         with:
           node-version: ${{ matrix.node }}
 
-      - name: Upgrade Node 5 npm
+      - name: Upgrade Node <= 5 npm
         run: npm install -g npm@3
-        if: ${{ matrix.node == 5 }}
+        if: ${{ matrix.node <= 5 }}
 
       - run: npm install
 

From a1144dc0220929de0e9b7faf93d793c10e77f094 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Sun, 21 Aug 2022 19:19:33 -0400
Subject: [PATCH 2347/2348] test: run node 7 tests with upgraded npm re: #12297

---
 .github/workflows/test.yml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 7a4eb6af80d..861870b0dc7 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -22,6 +22,10 @@ jobs:
         run: npm install -g npm@3
         if: ${{ matrix.node <= 5 }}
 
+      - name: Upgrade Node 7 npm
+        run: npm install -g npm@6
+        if: ${{ matrix.node == 7 }}
+
       - run: npm install
 
       - name: Setup

From ca7996b125c1baf24b056c8fef10cfdd24dc1ae9 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Mon, 22 Aug 2022 13:28:12 -0400
Subject: [PATCH 2348/2348] chore: release 5.13.15

---
 History.md   | 5 +++++
 package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 6891820d86a..dc466dbb1c0 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+5.13.15 / 2022-08-22
+====================
+ * fix: backport fix for CVE-2022-2564 #12281 [shubanker](https://github.com/shubanker)
+ * docs: fix broken link from findandmodify method deprecation #11366 [laissonsilveira](https://github.com/laissonsilveira)
+
 5.13.14 / 2021-12-27
 ====================
  * fix(timestamps): avoid setting createdAt on documents that already exist but dont have createdAt #11024
diff --git a/package.json b/package.json
index 4a70cd5cb62..cbb17a6b225 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "mongoose",
   "description": "Mongoose MongoDB ODM",
-  "version": "5.13.14",
+  "version": "5.13.15",
   "author": "Guillermo Rauch <guillermo@learnboost.com>",
   "keywords": [
     "mongodb",